Search results for: the inorganic membrane
919 Study of a Cross-Flow Membrane to a Kidney Encapsulation Engineering Structures for Immunosuppression Filter
Authors: Sihyun Chae, Ryoto Arai, Waldo Concepcion, Paula Popescu
Abstract:
The kidneys perform an important role in the human hormones that regulate the blood pressure, produce an active form of vitamin D and control the production of red blood cells. Kidney disease can cause health problems, such as heart disease. Also, increase the chance of having a stroke or heart attack. There are mainly to types of treatments for kidney disease, dialysis, and kidney transplant. For a better quality of life, the kidney transplant is desirable. However, kidney transplant can cause antibody reaction and patients’ body would be attacked by immune system of their own. For solving that issue, patients with transplanted kidney always take immunosuppressive drugs which can hurt kidney as side effects. Patients willing to do a kidney transplant have a waiting time of 3.6 years in average searching to find an appropriate kidney, considering there are almost 96,380 patients waiting for kidney transplant. There is a promising method to solve these issues: bioartificial kidney. Our membrane is specially designed with unique perforations capable to filter the blood cells separating the white blood cells from red blood cells. White blood cells will not pass through the encapsulated kidney preventing the immune system to attack the new organ and eliminating the need of a matching donor. It is possible to construct life-time long encapsulation without needing pumps or a power supply on the cell’s separation method preventing futures surgeries due the Cross-Channel Flow inside the device. This technology allows the possibility to use an animal kidney, prevent cancer cells to spread through the body, arm and leg transplants in the future. This project aims to improve the quality of life of patients with kidney disease.Keywords: kidney encapsulation, immunosuppression filter, leukocyte filter, leukocyte
Procedia PDF Downloads 201918 Characterization of Natural Polymers for Guided Bone Regeneration Applications
Authors: Benedetta Isella, Aleksander Drinic, Alissa Heim, Phillip Czichowski, Lisa Lauts, Hans Leemhuis
Abstract:
Introduction: Membranes for guided bone regeneration are essential to perform a barrier function between the soft and the regenerating bone tissue. Bioabsorbable membranes are desirable in this field as they do not require a secondary surgery for removal, decreasing patient surgical risk. Collagen was the first bioabsorbable alternative introduced on the market, but its degradation time may be too fast to guarantee bone regeneration, and optimisation is needed. Silk fibroin, being biocompatible, slowly bioabsorbable, and processable into different scaffold types, could be a promising alternative. Objectives: The objective is to compare the general performance of a silk fibroin membrane for guided bone regeneration to current collagen alternatives developing suitable standardized tests for the mechanical and morphological characterization. Methods: Silk fibroin and collagen-based membranes were compared from the morphological and chemical perspective, with techniques such as SEM imaging and from the mechanical point of view with techniques such as tensile and suture retention strength (SRS) tests. Results: Silk fibroin revealed a high degree of reproducibility in surface density. The SRS of silk fibroin (0.76 ± 0.04 N), although lower than collagen, was still comparable to native tissues such as the internal mammary artery (0.56 N), and the same can be extended to general mechanical behaviour in tensile tests. The SRS could be increased by an increase in thickness. Conclusion: Silk fibroin is a promising material in the field of guided bone regeneration, covering the interesting position of not being considered a product containing cells or tissues of animal origin from the regulatory perspective and having longer degradation times with respect to collagen.Keywords: guided bone regeneration, mechanical characterization, membrane, silk fibroin
Procedia PDF Downloads 42917 ADCOR © Muscle Damage Rapid Detection Test Based on Skeletal Troponin I Immunochromatography Reaction
Authors: Muhammad Solikhudin Nafi, Wahyu Afif Mufida, Mita Erna Wati, Fitri Setyani Rokim, M. Al-Rizqi Dharma Fauzi
Abstract:
High dose activity without any pre-exercise will impact Delayed Onset Muscle Soreness (DOMS). DOMS known as delayed pain post-exercise and induce skeletal injury which will decrease athletes’ performances. From now on, post-exercise muscle damage can be detected by measuring skeletal troponin I (sTnI) concentration in serum using ELISA but this method needs more time and cost. To prevent decreased athletes performances, screening need to be done rapidly. We want to introduce our new prototype to detect DOMS acutely. Rapid detection tests are based on immunological reaction between skeletal troponin I antibodies and sTnI in human serum or whole blood. Chemical methods that are used in the manufacture of diagnostic test is lateral flow immunoassay. The material used is rat monoclonal antibody sTnI, colloidal gold, anti-mouse IgG, nitrocellulose membrane, conjugate pad, sample pad, wick and backing card. The procedure are made conjugate (colloidal gold and mAb sTnI) and insert into the conjugate pad, gives spray sTnI mAb and anti-mouse IgG into nitrocellulose membrane, and assemble RDT. RDT had been evaluated by measuring the sensitivity of positive human serum (n = 30) and negative human serum (n = 30). Overall sensitivity value was 93% and specificity value was 90%. ADCOR as the first rapid detection test qualitatively showed antigen-antibody reaction and showed good overall performances for screening of muscle damage. Furthermore, these finding still need more improvements to get best results.Keywords: DOMS, sTnI, rapid detection test, ELISA
Procedia PDF Downloads 513916 Air–Water Two-Phase Flow Patterns in PEMFC Microchannels
Authors: Ibrahim Rassoul, A. Serir, E-K. Si Ahmed, J. Legrand
Abstract:
The acronym PEM refers to Proton Exchange Membrane or alternatively Polymer Electrolyte Membrane. Due to its high efficiency, low operating temperature (30–80 °C), and rapid evolution over the past decade, PEMFCs are increasingly emerging as a viable alternative clean power source for automobile and stationary applications. Before PEMFCs can be employed to power automobiles and homes, several key technical challenges must be properly addressed. One technical challenge is elucidating the mechanisms underlying water transport in and removal from PEMFCs. On one hand, sufficient water is needed in the polymer electrolyte membrane or PEM to maintain sufficiently high proton conductivity. On the other hand, too much liquid water present in the cathode can cause “flooding” (that is, pore space is filled with excessive liquid water) and hinder the transport of the oxygen reactant from the gas flow channel (GFC) to the three-phase reaction sites. The experimental transparent fuel cell used in this work was designed to represent actual full scale of fuel cell geometry. According to the operating conditions, a number of flow regimes may appear in the microchannel: droplet flow, blockage water liquid bridge /plug (concave and convex forms), slug/plug flow and film flow. Some of flow patterns are new, while others have been already observed in PEMFC microchannels. An algorithm in MATLAB was developed to automatically determine the flow structure (e.g. slug, droplet, plug, and film) of detected liquid water in the test microchannels and yield information pertaining to the distribution of water among the different flow structures. A video processing algorithm was developed to automatically detect dynamic and static liquid water present in the gas channels and generate relevant quantitative information. The potential benefit of this software allows the user to obtain a more precise and systematic way to obtain measurements from images of small objects. The void fractions are also determined based on images analysis. The aim of this work is to provide a comprehensive characterization of two-phase flow in an operating fuel cell which can be used towards the optimization of water management and informs design guidelines for gas delivery microchannels for fuel cells and its essential in the design and control of diverse applications. The approach will combine numerical modeling with experimental visualization and measurements.Keywords: polymer electrolyte fuel cell, air-water two phase flow, gas diffusion layer, microchannels, advancing contact angle, receding contact angle, void fraction, surface tension, image processing
Procedia PDF Downloads 312915 Morphology, Qualitative, and Quantitative Elemental Analysis of Pheasant Eggshells in Thailand
Authors: Kalaya Sribuddhachart, Mayuree Pumipaiboon, Mayuva Youngsabanant-Areekijseree
Abstract:
The ultrastructure of 20 species of pheasant eggshells in Thailand, (Simese Fireback, Lophura diardi), (Silver Pheasant, Lophura nycthemera), (Kalij Pheasant, Lophura leucomelanos crawfurdii), (Kalij Pheasant, Lophura leucomelanos lineata), (Red Junglefowl, Gallus gallus spadiceus), (Crested Fireback, Lophura ignita rufa), (Green Peafowl, Pavo muticus), (Indian Peafowl, Pavo cristatus), (Grey Peacock Pheasant, Polyplectron bicalcaratum bicalcaratum), (Lesser Bornean Fireback, Lophura ignita ignita), (Green Junglefowl, Gallus varius), (Hume's Pheasant, Syrmaticus humiae humiae), (Himalayan Monal, Lophophorus impejanus), Golden Pheasant, Chrysolophus pictus, (Ring-Neck Pheasant, Phasianus sp.), (Reeves’s Pheasant, Syrmaticus reevesi), (Polish Chicken, Gallus sp.), (Brahma Chicken, Gallus sp.), (Yellow Golden Pheasant, Chrysolophus pictus luteus), and (Lady Amhersts Pheasant, Chrysolophus amherstiae) were studied by Secondary electron imaging (SEI) and Energy dispersive X-ray analysis (EDX) detectors of scanning electron microscope. Generally, all pheasant eggshells showed 3 layers of cuticle, palisade, and mammillary. The total thickness was ranging from 190.28±5.94-838.96±16.31µm. The palisade layer is the most thickness layer following by mammillary and cuticle layers. The palisade layer in all pheasant eggshells consisted of numerous vesicle holes that were firmly forming as network thorough the layer. The vesicle holes in all pheasant eggshells had difference porosity ranging from 0.44±0.11-0.23±0.05 µm. While the mammillary layer was the most compact layer with a variable shape (broad-base V and U-shape) connect to shell membrane. Elemental analysis by of 20 specie eggshells showed 9 apparent elements including carbon (C), oxygen (O), calcium (Ca), phosphorous (P), sulfur (S), magnesium (Mg), silicon (Si), aluminum (Al), and copper (Cu) at the percentage of 28.90- 8.33%, 60.64-27.61%, 55.30-14.49%, 1.97-0.03%, 0.08-0.03%, 0.50-0.16%, 0.30-0.04%, 0.06-0.02%, and 2.67-1.73%, respectively. It was found that Ca, C, and O showed highest elemental compositions, which essential for pheasant embryonic development, mainly presented as composited structure of calcium carbonate (CaCO3) more than 97%. Meanwhile, Mg, S, Si, Al, and P were major inorganic constituents of the eggshells which directly related to an increase of the shell hardness. Finally, the percentage of heavy metal copper (Cu) has been observed in 4 eggshell species. There are Golden Pheasant (2.67±0.16%), Indian Peafowl (2.61±0.13%), Green Peafowl (1.97±0.74%), and Silver Pheasant (1.73±0.11%), respectively. A non-significant difference was found in the percentages of 9 elements in all pheasant eggshells. This study is useful to provide the information of biology and taxonomic of pheasant study in Thailand for conservation.Keywords: pheasants eggshells, secondary electron imaging (SEI) and energy dispersive X-ray analysis (EDX), morphology, Thailand
Procedia PDF Downloads 235914 CuIn₃Se₅ Colloidal Nanocrystals and Its Ink-Coated Films for Photovoltaics
Authors: M. Ghali, M. Elnimr, G. F. Ali, A. M. Eissa, H. Talaat
Abstract:
CuIn₃Se₅ material is indexed as ordered vacancy compounds having excellent matching properties with CuInGaSe (CIGS) solar absorber layer. For example, the valence band offset of CuIn₃Se₅ with CIGS is nearly 0.3 eV, and the lattice mismatch is less than 1%, besides the absence of discontinuity in their conduction bands. Thus, CuIn₃Se₅ can work as a passivation layer for repelling holes from CIGS/CdS interface and hence to reduce the interface carriers recombination and consequently enhancing the efficiency of CIGS/CdS solar cells. Theoretically, it was reported earlier that an improvement in the efficiency of p-CIGS-based solar cell with a thin ~100 nm of n-CuIn₃Se₅ layer is expected. Recently, a reported experiment demonstrated significant improvement in the efficiency of Molecular Beam Epitaxy (MBE) grown CIGS solar cells from 13.4 to 14.5% via inserting a thin layer of MBE-grown Cu(In,Ga)₃Se₅ layer at the CdS/CIGS interface. It should be mentioned that CuIn₃Se₅ material in either bulk or thin film form, are usually fabricated by high vacuum physical vapor deposition techniques (e.g., three-source co-evaporation, RF sputtering, flash evaporation, and molecular beam epitaxy). In addition, achieving photosensitive films of n-CuIn₃Se₅ material is important for new hybrid organic/inorganic structures, where inorganic photo-absorber layer, with n-type conductivity, can form n–p junction with organic p-type material (e.g., conductive polymers). A detailed study of the physical properties of CuIn₃Se₅ is still necessary for better understanding of device operation and further improvement of solar cells performance. Here, we report on the low-cost synthesis of CuIn₃Se₅ material in nano-scale size, with an average diameter ~10nm, using simple solution-based colloidal chemistry. In contrast to traditionally grown bulk tetragonal CuIn₃Se₅ crystals using high Vacuum-based technology, our colloidal CuIn₃Se₅ nanocrystals show cubic crystal structure with a shape of nanoparticles and band gap ~1.33 eV. Ink-coated thin films prepared from these nanocrystals colloids; display n-type character, 1.26 eV band gap and strong photo-responsive behavior with incident white light. This suggests the potential use of colloidal CuIn₃Se₅ as an active layer in all-solution-processed thin film solar cells.Keywords: nanocrystals, CuInSe, thin film, optical properties
Procedia PDF Downloads 155913 Deciphering Specific Host-Selective Toxin Interaction of Cassiicolin with Lipid Membranes and its Cytotoxicity on Rubber Leaves
Authors: Kien Xuan Ngo
Abstract:
Cassiicolin (Cas), a toxin produced by Corynespora cassiicola, is responsible for corynespora leaf fall (CLF) disease in rubber trees. Currently, the molecular mechanism of the cytotoxicity of Cas isoforms (i.e., Cas1, Cas2) on rubber leaves and its host selectivity have not been fully elucidated. This study analyzed the binding of Cas1 and Cas2 to membranes consisting of different plant lipids and their membrane-disruption activities. Using high-speed atomic force microscopy and confocal microscopy, this study reveals that the binding and disruption activities of Cas1 and Cas2 on lipid membranes are strongly dependent on the specific plant lipids. The negative phospholipids, glycerolipids, and sterols are more susceptible to membrane damage caused by Cas1 and Cas2 than neutral phospholipids and betaine lipids. In summary, This study unveils that (i) Cas1 and Cas2 directly damage and cause necrosis in the leaves of specific rubber clones; (ii) Cas1 and Cas2 can form biofilm-like structures on specific lipid membranes (negative phospholipids, glycerolipids, and sterols). The biofilm-like formation of Cas toxin plays an important role in selective disruption on lipid membranes; (iii) Vulnerability of the specific cytoplasmic membranes to the selective Cas toxin is the most remarkable feature of cytotoxicity of Cas toxin on plant cells. Finally, researcher’s exploration is crucial to understand the basic molecular mechanism underlying the host-selective toxic interaction of Cas toxin with cytoplasmic membranes in plant cells.Keywords: cassiicolin, corynespora leaf fall disease, high-speed AFM, giant liposome vesicles
Procedia PDF Downloads 123912 Innovative Grafting of Polyvinylpyrrolidone onto Polybenzimidazole Proton Exchange Membranes for Enhanced High-Temperature Fuel Cell Performance
Authors: Zeyu Zhou, Ziyu Zhao, Xiaochen Yang, Ling AI, Heng Zhai, Stuart Holmes
Abstract:
As a promising sustainable alternative to traditional fossil fuels, fuel cell technology is highly favoured due to its enhanced working efficiency and reduced emissions. In the context of high-temperature fuel cells (operating above 100 °C), the most commonly used proton exchange membrane (PEM) is the Polybenzimidazole (PBI) doped phosphoric acid (PA) membrane. Grafting is a promising strategy to advance PA-doped PBI PEM technology. The existing grafting modification on PBI PEMs mainly focuses on grafting phosphate-containing or alkaline groups onto the PBI molecular chains. However, quaternary ammonium-based grafting approaches face a common challenge. To initiate the N-alkylation reaction, deacidifying agents such as NaH, NaOH, KOH, K2CO3, etc., can lead to ionic crosslinking between the quaternary ammonium group and PBI. Polyvinylpyrrolidone (PVP) is another widely used polymer, the N-heterocycle groups within PVP endow it with a significant ability to absorb PA. Recently, PVP has attracted substantial attention in the field of fuel cells due to its reduced environmental impact and impressive fuel cell performance. However, due to the the poor compatibility of PVP in PBI, few research apply PVP in PA-doped PBI PEMs. This work introduces an innovative strategy to graft PVP onto PBI to form a network-like polymer. Due to the absence of quaternary ammonium groups, PVP does not pose issues related to crosslinking with PBI. Moreover, the nitrogen-containing functional groups on PVP provide PBI with a robust phosphoric acid retention ability. The nuclear magnetic resonance (NMR) hydrogen spectrum analysis results indicate the successful completion of the grafting reaction where N-alkylation reactions happen on both sides of the grafting agent 1,4-bis(chloromethyl)benzene. On one side, the reaction takes place with the hydrogen atoms on the imidazole groups of PBI, while on the other side, it reacts with the terminal amino group of PVP. The XPS results provide additional evidence from the perspective of the element. On synthesized PBI-g-PVP surfaces, there is an absence of chlorine (chlorine in grafting agent 1,4-bis(chloromethyl)benzene is substituted) element but a presence of sulfur element (sulfur element in terminal amino PVP appears in PBI), which demonstrates the occurrence of the grafting reaction and PVP is successfully grafted onto PBI. Prepare these modified membranes into MEA. It was found that during the fuel cell operation, all the grafted membranes showed substantial improvement in maximum current density and peak power density compared to unmodified one. For PBI-g-PVP 30, with a grafting degree of 22.4%, the peak power density reaches 1312 mW cm⁻², marking a 59.6% enhancement compared to the pristine PBI membrane. The improvement is caused by the improved PA binding ability of the membrane after grafting. The AST test result shows that the grafting membranes have better long-term durability and performance than unmodified membranes attributed to the presence of added PA binding sites, which can effectively prevent the PA leaching caused by proton migration. In conclusion, the test results indicate that grafting PVP onto PBI is a promising strategy which can effectively improve the fuel cell performance.Keywords: fuel cell, grafting modification, PA doping ability, PVP
Procedia PDF Downloads 79911 Comparison of Cervical Length Using Transvaginal Ultrasonography and Bishop Score to Predict Succesful Induction
Authors: Lubena Achmad, Herman Kristanto, Julian Dewantiningrum
Abstract:
Background: The Bishop score is a standard method used to predict the success of induction. This examination tends to be subjective with high inter and intraobserver variability, so it was presumed to have a low predictive value in terms of the outcome of labor induction. Cervical length measurement using transvaginal ultrasound is considered to be more objective to assess the cervical length. Meanwhile, this examination is not a complicated procedure and less invasive than vaginal touché. Objective: To compare transvaginal ultrasound and Bishop score in predicting successful induction. Methods: This study was a prospective cohort study. One hundred and twenty women with singleton pregnancies undergoing induction of labor at 37 – 42 weeks and met inclusion and exclusion criteria were enrolled in this study. Cervical assessment by both transvaginal ultrasound and Bishop score were conducted prior induction. The success of labor induction was defined as an ability to achieve active phase ≤ 12 hours after induction. To figure out the best cut-off point of cervical length and Bishop score, receiver operating characteristic (ROC) curves were plotted. Logistic regression analysis was used to determine which factors best-predicted induction success. Results: This study showed significant differences in terms of age, premature rupture of the membrane, the Bishop score, cervical length and funneling as significant predictors of successful induction. Using ROC curves found that the best cut-off point for prediction of successful induction was 25.45 mm for cervical length and 3 for Bishop score. Logistic regression was performed and showed only premature rupture of membranes and cervical length ≤ 25.45 that significantly predicted the success of labor induction. By excluding premature rupture of the membrane as the indication of induction, cervical length less than 25.3 mm was a better predictor of successful induction. Conclusion: Compared to Bishop score, cervical length using transvaginal ultrasound was a better predictor of successful induction.Keywords: Bishop Score, cervical length, induction, successful induction, transvaginal sonography
Procedia PDF Downloads 325910 Isolation and Characterisation of Novel Environmental Bacteriophages Which Target the Escherichia coli Lamb Outer Membrane Protein
Authors: Ziyue Zeng
Abstract:
Bacteriophages are viruses which infect bacteria specifically. Over the past decades, phage λ has been extensively studied, especially its interaction with the Escherichia coli LamB (EcLamB) protein receptor. Nonetheless, despite the enormous numbers and near-ubiquity of environmental phages, aside from phage λ, there is a paucity of information on other phages which target EcLamB as a receptor. In this study, to answer the question of whether there are other EcLamB-targeting phages in the natural environment, a simple and convenient method was developed and used for isolating environmental phages which target a particular surface structure of a particular bacterium; in this case, the EcLamB outer membrane protein. From the enrichments with the engineered bacterial hosts, a collection of EcLamB-targeting phages (ΦZZ phages) were easily isolated. Intriguingly, unlike phage λ, an obligate EcLamB-dependent phage in the Siphoviridae family, the newly isolated ΦZZ phages alternatively recognised EcLamB or E. coli OmpC (EcOmpC) as a receptor when infecting E. coli. Furthermore, ΦZZ phages were suggested to represent new species in the Tequatrovirus genus in the Myoviridae family, based on phage morphology and genomic sequences. Most phages are thought to have a narrow host range due to their exquisite specificity in receptor recognition. With the ability to optionally recognise two receptors, ΦZZ phages were considered relatively promiscuous. Via the heterologous expression of EcLamB on the bacterial cell surface, the host range of ΦZZ phages was further extended to three different enterobacterial genera. Besides, an interesting selection of evolved phage mutants with a broader host range was isolated, and the key mutations involved in their evolution to adapt to new hosts were investigated by genomic analysis. Finally, and importantly, two ΦZZ phages were found to be putative generalised transducers, which could be exploited as tools for DNA manipulations.Keywords: environmental microbiology, phage, microbe-host interactions, microbial ecology
Procedia PDF Downloads 100909 Enhancing Mitochondrial Activity and Metabolism in Aging Female Germ Cells: Synergistic Effects of Dual ROCK and ROS Inhibition
Authors: Kuan-Hao Tsui, Li-Te Lin, Chia-Jung Li
Abstract:
The combination of Y-27632 and Vitamin C significantly enhances the quality of aging germ cells by reducing reactive oxygen species (ROS) production, restoring mitochondrial membrane potential balance, and promoting mitochondrial fusion. The age-related decline in oocyte quality contributes to reduced fertility, increased aneuploidy, and diminished embryo quality, with mitochondrial dysfunction in both oocytes and granulosa cells being a key factor in this decline. Experiments on aging germ cells investigated the effects of the Y-27632 and Vitamin C combination. In vivo studies involved aged mice to assess oocyte maturation and ROS accumulation during culture. The assessment included mitochondrial activity, ROS levels, mitochondrial membrane potential, and mitochondrial dynamics. Cellular energy metabolism and ATP production were also measured. The combination treatment effectively addressed mitochondrial dysfunction and regulated cellular energy metabolism, promoting oxygen respiration and increasing ATP production. In aged mice, this supplement treatment enhanced in vitro oocyte maturation and prevented ROS accumulation in aging oocytes during culture. While these findings are promising, further research is needed to explore the long-term effects and potential side effects of the Y-27632 and Vitamin C combination. Additionally, translating these findings to human subjects requires careful consideration. Overall, the study suggests that the Y-27632 and Vitamin C combination could be a promising intervention to mitigate aging-related dysfunction in germ cells, potentially enhancing oocyte quality, particularly in the context of in vitro fertilization.Keywords: ovarian aging, supplements, ROS, mitochondria
Procedia PDF Downloads 40908 Colloids and Heavy Metals in Groundwaters: Tangential Flow Filtration Method for Study of Metal Distribution on Different Sizes of Colloids
Authors: Jiancheng Zheng
Abstract:
When metals are released into water from mining activities, they undergo changes chemically, physically and biologically and then may become more mobile and transportable along the waterway from their original sites. Natural colloids, including both organic and inorganic entities, are naturally occurring in any aquatic environment with sizes in the nanometer range. Natural colloids in a water system play an important role, quite often a key role, in binding and transporting compounds. When assessing and evaluating metals in natural waters, their sources, mobility, fate, and distribution patterns in the system are the major concerns from the point of view of assessing environmental contamination and pollution during resource development. There are a few ways to quantify colloids and accordingly study how metals distribute on different sizes of colloids. Current research results show that the presence of colloids can enhance the transport of some heavy metals in water, while heavy metals may also have an influence on the transport of colloids when cations in the water system change colloids and/or the ion strength of the water system changes. Therefore, studies into the relationship between different sizes of colloids and different metals in a water system are necessary and needed as natural colloids in water systems are complex mixtures of both organic and inorganic as well as biological materials. Their stability could be sensitive to changes in their shapes, phases, hardness and functionalities due to coagulation and deposition et al. and chemical, physical, and biological reactions. Because metal contaminants’ adsorption on surfaces of colloids is closely related to colloid properties, it is desired to fraction water samples as soon as possible after a sample is taken in the natural environment in order to avoid changes to water samples during transportation and storage. For this reason, this study carried out groundwater sample processing in the field, using Prep/Scale tangential flow filtration systems with 3-level cartridges (1 kDa, 10 kDa and 100 kDa). Groundwater samples from seven sites at Fort MacMurray, Alberta, Canada, were fractionated during the 2015 field sampling season. All samples were processed within 3 hours after samples were taken. Preliminary results show that although the distribution pattern of metals on colloids may vary with different samples taken from different sites, some elements often tend to larger colloids (such as Fe and Re), some to finer colloids (such as Sb and Zn), while some of them mainly in the dissolved form (such as Mo and Be). This information is useful to evaluate and project the fate and mobility of different metals in the groundwaters and possibly in environmental water systems.Keywords: metal, colloid, groundwater, mobility, fractionation, sorption
Procedia PDF Downloads 362907 Synthetic Coumarin Derivatives and Their Anticancer Properties
Authors: Kabange Kasumbwe, Viresh Mohanlall, Bharti Odhav, Venu Narayanaswamy
Abstract:
Coumarins are naturally occurring plant metabolites known for their pharmacological properties such as anticoagulant, antimicrobial, anticancer, antioxidant, anti-inflammatory and antiviral properties. The pharmacological and biochemical properties and curative applications of coumarins depend on the substitution around the coumarin core structure. In the present study, seven halogenated coumarins CMRN1-CMRN7 were synthesized and evaluated for their anticancer activity. The cytotoxicity potential of the test compounds was evaluated against UACC62 (Melanoma), MCF-7 (Breast cancer) and PBM (Peripheral Blood Mononuclear) cell lines using MTT assay keeping doxorubicin as standard drug. The apoptotic potential of the coumarin compounds was evaluated against UACC62 (Melanoma) cell by assessing their morphological changes, membrane change, mitochondria membrane potential; pro-apoptotic changes were investigated using the AnnexinV-PI staining, JC-1, caspase-3 enzyme kits respectively on flow cytometer. The synthetic coumarin has strongly suppressed the cell proliferation of UACC-62 (Melanoma) and MCF-7 (Breast) Cancer cells, the higher toxicity of these compounds against UACC-62 (Melanoma) and MCF-7 (Breast) were CMRN3, CMRN4, CMRN5, CMRN6. However, compounds CMRN1, CMRN2, and CMRN7 had no significant inhibitory effect. Furthermore the active compounds CMRN3, CMRN4, CMRN5, CMRN6 exerted antiproliferative effects through apoptosis induction against UACC-62 (Melanoma), suggesting their potential could be considered as attractive lead molecules in the future for the development of potential anticancer agents since one of the important criteria in the development of therapeutic drugs for cancer treatment is to have high selectivity and less or no side-effects on normal cells and these compounds had no inhibitory effect against the PBMC cells.Keywords: coumarin, MTT, apoptosis, cytotoxicity
Procedia PDF Downloads 238906 Apoptosis Inducing Potential of Onosma Bracteata Wall. in Mg-63 Human Osteosarcoma Cells via cdk2/Cyclin E Pathway
Authors: Ajay Kumar, Satwinderjeet Kaur
Abstract:
Onosma bracteata Wall. (Boraginaceae), is known to be a medicinal plant, useful in the treatment of body swellings, abdominal pain and urinary calculi, etc. The present study focused on the radical scavenging and cancer growth inhibitory properties of isolates from O. bracteata. Obea fraction demonstrated noticeable free radical scavenging ability along with antiproliferative activity in human osteosarcoma MG-63, human neuroblastoma IMR-32, and human lung cancer A549 cell lines using MTT assay with GI50 values of 88.56, 101.61 and 112.7 μg/ml, respectively. The scanning electron and confocal microscopy studies showed morphological alterations including nuclear condensation and formation of apoptotic bodies in osteosarcoma MG-63 cells. Obea fraction in osteosarcoma MG-63 cells augmented the reactive oxygen species (ROS) level and decreased the mitochondrial membrane potential. Flow cytometry analysis revealed the Obea treated cells to be arrested in the G0/G1 phase in a dose dependent manner supported by the observed increase in the early apoptotic cell population. Western blotting analysis showed that the expression of p-NF-kB, COX-2, p-Akt, and Bcl-xL decreased whereas, the expression of GSK-3β, p53, caspase-3 and caspase-9 proteins increased. The downregulation of Bcl-2, Cyclin E, CDK2 and mortalin gene expression and upregulation of p53 genes was unfolded in RT-qPCR studies. The presence of catechin, kaempferol, Onosmin A and epicatechin, as revealed in high-performance liquid chromatography (HPLC) studies, contributes towards the chemopreventive potential of O. bracteata which can be tapped for chemotherapeutic use.Keywords: apoptosis, confocal microscopy, HPLC, mitochondria membrane potential, reactive oxygen species
Procedia PDF Downloads 136905 Physical Contact Modulation of Macrophage-Mediated Anti-Inflammatory Response in Osteoimmune Microenvironment by Pollen-Like Nanoparticles
Authors: Qing Zhang, Janak L. Pathak, Macro N. Helder, Richard T. Jaspers, Yin Xiao
Abstract:
Introduction: Nanomaterial-based bone regeneration is greatly influenced by the immune microenvironment. Tissue-engineered nanomaterials mediate the inflammatory response of macrophages to regulate bone regeneration. Silica nanoparticles have been widely used in tissue engineering-related preclinical studies. However, the effect of topological features on the surface of silica nanoparticles on the immune response of macrophages remains unknown. Purposes: The aims of this research are to compare the influences of normal and pollen-like silica nano-surface topography on macrophage immune responses and to obtain insight into their potential regulatory mechanisms. Method: Macrophages (RAW 264.7 cells) were exposed to mesoporous silica nanoparticles with normal morphology (MSNs) and pollen-like morphology (PMSNs). RNA-seq, RT-qPCR, and LSCM were used to assess the changes in expression levels of immune response-related genes and proteins. SEM and TEM were executed to evaluate the contact and adherence of silica nanoparticles by macrophages. For the assessment of the immunomodulation-mediated osteogenic potential, BMSCs were cultured with conditioned medium (CM) from LPS pre-stimulated macrophage cultures treated with MSNs or PMSNs. Osteoimmunomodulatory potential of MSNs and PMSNs in vivo was tested in a mouse cranial bone osteolysis model. Results: The results of the RNA-seq, RT-qPCR, and LSCM assays showed that PMSNs inhibited the expression of pro-inflammatory genes and proteins in macrophages. SEM images showed distinct macrophage membrane surface binding patterns of MSNs and PMSNs. MSNs were more evenly dispersed across the macrophage cell membrane, while PMSNs were aggregated. PMSNs-induced macrophage anti-inflammatory response was associated with upregulation of the cell surface receptor CD28 and inhibition of ERK phosphorylation. TEM images showed that both MSNs and PMSNs could be phagocytosed by macrophages, and inhibiting nanoparticle phagocytosis did not affect the expression of anti-inflammatory genes and proteins. Moreover, PMSNs-induced conditioned medium from macrophages enhanced BMP-2 expression and osteogenic differentiation mBMSCs. Similarly, PMSNs prevented LPS-induced bone resorption via downregulation of inflammatory reaction. Conclusions: PMSNs can promote bone regeneration by modulating osteoimmunological processes through surface topography. The study offers insights into how surface physical contact cues can modulate the regulation of osteoimmunology and provides a basis for the application of nanoparticles with pollen-like morphology to affect immunomodulation in bone tissue engineering and regeneration.Keywords: physical contact, osteoimmunology, macrophages, silica nanoparticles, surface morphology, membrane receptor, osteogenesis, inflammation
Procedia PDF Downloads 61904 Traumatic Osteoarthritis Induces Mechanical Hyperalgesia through IL-1β/TNF-α-Mediated Upregulation of the Sema4D Gene Expression
Authors: Hsiao-Chien Tsai, Yu-Pin Chen, Ruei-Ming Chen
Abstract:
Introduction: Osteoarthritis (OA) is characterized by joint destruction and causes chronic disability. One of the prominent symptoms is pain. Alleviating the pain is necessary and urgent for the therapy of OA patients. However, currently, understanding the mechanisms that drive OA-induced pain remains challenging, which hampers the optimistic management of pain in OA patients. Semaphorin 4D (Sema4D) participates in axon guidance pathway and bone remodeling, thus, may play a role in the regulation of pain in OA. In this study, we have established a rat model of OA to find out the mechanisms of OA-induced pain and to deliberate the roles of Sema4D. Methods: Behavioral changes and the pro-inflammatory cytokines (IL-1β, TNF-α, and IL-17) associated with pain were measured during the development of OA. Sema4D expression in cartilage and synovial membrane at 1, 4, and 12 weeks after inducing OA was analyzed. To assess if Sema4D is related to the neurogenesis in OA as an axon repellant, we analyzed the expression of PGP9.5 as well. Results: Synovitis and cartilage degradation were evident histologically during the development of OA. Mechanical hyperalgesia was most severe at week 1, then persisted thereafter. It was associated with stress coping strategies. Similar to the pain behavioral results, levels of IL-1β and TNF-α in synovial lavage fluid were significantly elevated in the OA group at weeks 1 and 4, respectively. Sema4D expression in cartilage and the synovial membrane was also enhanced in the OA group and was correlated with pain and pro-inflammatory cytokines. The marker of neurogenesis, PGP9.5, was also enhanced during the development of OA. Discussion: OA induced mechanical hyperalgesia, which might be through upregulating IL-1β/TNF-α-mediated Sema4D expressions. If anti-Sema4D treatment could reduce OA-induced mechanical hyperalgesia and prevent the subsequent progression of OA needs to be further investigated. Significance: OA can induce mechanical hyperalgesia through upregulation of IL-1β/TNF-α-mediated Sema4D and PGP9.5 expressions. And the upregulation of Sema4D may indicate the severity or active status of OA and OA-induced pain.Keywords: traumatic osteoarthritis, mechanical hyperalgesia, Sema4D, inflammatory cytokines
Procedia PDF Downloads 78903 Hospice-Shared Care for a Child Patient Supported with Extracorporeal Membrane Oxygenation
Authors: Hsiao-Lin Fang
Abstract:
Every life is precious, and comprehensive care should be provided to individuals who are in the final stages of their lives. Hospice-shared care aims to provide optimal symptom control and palliative care to terminal (cancer) patients through the implementation of shared care, and to support patients and their families in making various physical and psychological adjustments in the face of death. This report examines a 10-year-boy diagnosed with Out-of-Hospital Cardiac Arrest (OHCA). The individual fainted when swimming at school and underwent 31 minutes of cardiopulmonary resuscitation (CPR). While receiving treatment at the hospital, the individual received extracorporeal membrane oxygenation(ECMO) due to unstable hemodynamics. Urgent cardiac catheterization found: Suspect acute fulminant myocarditis or underlying cardiomyopathy with acute decompensation, After the active rescue by the medical team, hemodynamics still showed only mean pressure value. With respect to the patient, interdepartmental hospice-shared care was implemented and a do-not-resuscitate (DNR) order was signed after family discussions were conducted. Assistance and instructions were provided as part of the comfort care process. A farewell gathering attended by the patient’s relatives, friends, teachers, and classmates was organized in an intensive care unit (ICU) in order to look back on the patient’s life and the beautiful memories that were created, as well as to alleviate the sorrow felt by family members, including the patient’s father and sister. For example, the patient was presented with drawings and accompanied to a garden to pick flowers. In this manner, the patient was able to say goodbye before death. Finally, the patient’s grandmother and father participated in the clinical hospice care and post-mortem care processes. A hospice-shared care clinician conducted regular follow-ups and provided care to the family of the deceased, supporting family members through the sorrowful period. Birth, old age, sickness, and death are the natural phases of human life. In recent years, growing attention has been paid to human-centered hospice care. Hospice care is individual holistic care provided by a professional team and it involves the provision of comprehensive care to a terminal patient. Hospice care aims to satisfy the physical, psychological, mental, and social needs of patients and their families. It does not involve the cessation of treatment but rather avoids the exacerbation or extension of the suffering endured by patients, thereby preserving the dignity and quality of life during the end-of-life period. Patients enjoy the company of others as they complete the last phase of their lives, and their families also receive guidance on how they can move on with their own lives after the patient’s death.Keywords: hospice-shared care, extracorporeal membrane oxygenation (ECMO), hospice-shared care, child patient
Procedia PDF Downloads 140902 Effect of Hormones Priming on Enzyme Activity and Lipid Peroxidation in Wheat Seed under Accelerated Aging
Authors: Amin Abbasi, Fariborz Shekari, Seyed Bahman Mousavi
Abstract:
Seed aging during storage is a complex biochemical and physiological processes that can lead to reduce seed germination. This phenomenon associated with increasing of total antioxidant activity during aging. To study the effects of hormones on seed aging, aged wheat seeds (control, 90 and 80% viabilities) were treated with GA3, Salicylic Acid, and paclobutrazol and antioxidant system were investigated as molecular biomarkers for seed vigor. The results showed that, seed priming treatment significantly affected germination percentage, normality seedling percentage, H2O2, MDA, CAT, APX, and GPX activates. Maximum germination percentage achieve in GA3 priming in control treatment. Germination percentage and normal seedling percentage increased in other GA3 priming treatment compared with other hormones. Also aging increased MDA, H2O2 content. MDA is considered sensitive marker commonly used for assessing membrane lipid peroxidation and H2O2result in toxicity to cellular membrane system and damages to plant cells. Amount of H2O2 and MDA declined in GA3 treatment. CAT, GPX and APX activities were reduced by increasing the aging time and at different levels of priming. The highest APX activity was observed in Salicylic Acid control treatment and the highest GPX and CAT activity was obtained in GA3 control treatment. The lowest MDA and H2O2 showed in GA3 control treatment, too. Hormone priming increased Antioxidant enzyme activity and decreased amount of reactive oxygen space and malondialdehyde (MDA) under aging treatment. Also, GA3 priming treatments have a significant effect on germination percentage and number of normal seedling. Generally aging seed, increase ROS and lipid peroxidation. Antioxidant enzymes activity of aged seeds increased after hormone priming.Keywords: hormones priming, wheat, aging seed, antioxidant, lipid peroxidation
Procedia PDF Downloads 496901 Surface Functionalized Biodegradable Polymersome for Targeted Drug Delivery
Authors: Susmita Roy, Madhavan Nallani
Abstract:
In recent years' polymersomes, self-assembled polymeric vesicles emerge from block copolymers, have been widely investigated due to their enhance stability and unique advantageous properties compared to their phospholipid counterpart, liposomes, dendrimers, and micelles. It provides a distinctive platform for advanced therapeutics and the creation of complex (bio) catalytically active systems for research in Nanomedicine and synthetic biology. Inspired by nature, where compartmentalization of biological components is all ubiquitous, we are interested in developing a platform technology of self-assembled multifunctional compartments with applications in areas from targeted drug/gene delivery, biosensing, pharmaceutical to cosmetics. Polymersome surfaces can be a proper choice of derivatization with a controlled amount of functional groups. To achieve site-specific targeting of polymersomes, biological recognition motives can be attached to the polymersomes surface by standard bioconjugation techniques, (like esterification, amidation, thiol-maleimide coupling, click-chemistry routes or other coupling methods). Herein, we are developing easy going, one-step bioconjugation strategies for site-specific surface functionalized biodegradable polymeric and/or polymer-lipid hybrid vesicles for targeted drug delivery. Biodegradable polymer, polycaprolactone-b-polyethylene glycol (PCL-PEG), polylactic acid-b-polyethylene glycol (PLA-PEG) and phospholipid, 1-palmitoyl-2- oleoyl-sn-glycero-3-phosphocholine (POPC) has been widely used for numerous vesicle formulations. Some of these drug-loaded formulations are being tested on mice for controlled release. These surface functionalized polymersomes are also appropriate for membrane protein reconstitution/insertion, antibodies conjugation and various bioconjugation with diverse targeted molecules for controlled drug delivery.Keywords: drug delivery, membrane protein, polymersome, surface modification
Procedia PDF Downloads 154900 Phytoremediation of Zn-Contaminated Soils by Malva Sylvestris
Authors: Abdelouahab Diafat, Meribai Abdelmalek, Ahmed Bahloul
Abstract:
phytoremediation is the use of plants to remove or degrade organic or inorganic contaminants from soil and water this work aims to study the potential effect of malva sylvestris for the phytoremediation of soils contaminated by Zn. plants were grown in pots containing soil artificially contaminated with Zn at concentrations of 100, 200, and 300 mg/kg. the results obtained show that the Zn concentrations used have a negative effect on the growth of this plant the search for the metal carried out by the technique of atomic absorption spectrometry shows that this plant accumulates a small quantity of this metal. it can be concluded that the malva sylvestris plant tolerates Zn contaminated soils but it is not considered as a zinc hyperaccumulator plantKeywords: phytoremidiation, Zn-contaminated soils, Malva Sylvestris, phytoextraction
Procedia PDF Downloads 86899 Advanced Lithium Recovery from Brine: 2D-Based Ion Selectivity Membranes
Authors: Nour S. Abdelrahman, Seunghyun Hong, Hassan A. Arafat, Daniel Choi, Faisal Al Marzooqi
Abstract:
Abstract—The advancement of lithium extraction methods from water sources, particularly saltwater brine, is gaining prominence in the lithium recovery industry due to its cost-effectiveness. Traditional techniques like recrystallization, chemical precipitation, and solvent extraction for metal recovery from seawater or brine are energy-intensive and exhibit low efficiency. Moreover, the extensive use of organic solvents poses environmental concerns. As a result, there's a growing demand for environmentally friendly lithium recovery methods. Membrane-based separation technology has emerged as a promising alternative, offering high energy efficiency and ease of continuous operation. In our study, we explored the potential of lithium-selective sieve channels constructed from layers of 2D graphene oxide and MXene (transition metal carbides and nitrides), integrated with surface – SO₃₋ groups. The arrangement of these 2D sheets creates interplanar spacing ranging from 0.3 to 0.8 nm, which forms a barrier against multivalent ions while facilitating lithium-ion movement through nano capillaries. The introduction of the sulfonate group provides an effective pathway for Li⁺ ions, with a calculated binding energy of Li⁺ – SO³⁻ at – 0.77 eV, the lowest among monovalent species. These modified membranes demonstrated remarkably rapid transport of Li⁺ ions, efficiently distinguishing them from other monovalent and divalent species. This selectivity is achieved through a combination of size exclusion and varying binding affinities. The graphene oxide channels in these membranes showed exceptional inter-cation selectivity, with a Li⁺/Mg²⁺ selectivity ratio exceeding 104, surpassing commercial membranes. Additionally, these membranes achieved over 94% rejection of MgCl₂.Keywords: ion permeation, lithium extraction, membrane-based separation, nanotechnology
Procedia PDF Downloads 71898 Effects of Pre-Storage Invigoration Treatments on Ageing Dendrocalamus hamiltonii Seeds
Authors: Geetika Richa, M. L. Sharma
Abstract:
Bamboo as an ancient herbal medicine has been used for thousands of years in Asia and goes by many names such as tabashir, banslochan etc. It is often used for its tonic and astringent properties. Modern analysis of bamboos show high amount of vitamins and minerals which makes them valuable as a curative. Bamboo leaf decoction and young shoots are known as remedy for intestinal worms, healing of ulcers and stomach disorders. Bamboos are known to be propagated by large scale plantations but propagation through seeds occurs very limited as they have very short viability of few months. Seeds loses viability over a period of time even under controlled conditions and important factors that affect seed viability is the decline in reserve food material, decrease in membrane integrity and fall in endogenous level of growth hormones. Invigoration treatments that include hydration, dehydration, incorporation of bioactive chemicals such as growth regulators, nutrients and antioxidants etc. improve the seed performance. Our studies were aimed to determine the most effective invigoration treatments to enhance vigour and viability of seeds by following invigoration treatments, i.e., hardening. Treated seeds were stored at controlled temperature and humidity (in desiccators at 4°C). In hardening, chemicals were applied in 3 different concentrations to three replicates of 10 seeds. Hardening was done withGA3, IAA, (each with concentrations of 10 ppm, 20 ppm and 50 ppm), calcium oxychloride, neem leaf powder and clay (each with concentrations of 2%, 5% and 10%). Statistically all the hardening materials were effective but GA3 50 ppm was the most effective one in maintaining germination percentage and vigour index. Hardening treatments increased the germination percentage of seeds, i.e. 86.2%, over control which showed germination percentage of 80.2%. It was concluded that in order to maintain seed viability during storage for longer period of time, invigoration treatments have been found to be very effective.Keywords: invigoration, seed quality, viability, hardening, membrane integrity, decoction
Procedia PDF Downloads 321897 Cytotoxicity thiamethoxam Study on the Hepatopancreas and Its Reversibility under the Effect of Ginger in Helix aspersa
Authors: Samira Bensoltane, Smina Ait Hamlet, Samti Meriem, Semmasel Asma
Abstract:
Living organisms in the soil are subject to regular fluctuations of abiotic parameters, as well as a chemical contamination of the environment due to human activities. They are subject to multiple stressors they face. The aim of our work was to study the effects of insecticide: thiamethoxam (neonicotinoid), and the potential reversibility of the effects by an antioxidant: ginger on a bioindicator species in ecotoxicology, the land snail Helix aspersa. The effects were studied by a targeted cell approach of evaluating the effect of these molecules on tissue and cellular aspect of hepatopancreas through histological study. Treatment with thiamethoxam concentrations 10, 20, and 40 mg/l shows signs of inflammation even at low concentrations and from the 5th day of treatment. Histological examination of the hepatopancreas of snails treated with thiamethoxam showed significant changes from the lowest concentrations tested , note intertubular connective tissue enlargement, necrosis deferent types of cells (cells with calcium , digestive, excretory) , also damage acini, alteration of the apical membrane and lysis of the basement membrane in a dose- dependent manner. After 10 days of treatment and with 40 mg/l, the same changes were observed with a very advanced degeneration of the wall of the member that could be confused with the cell debris. For cons, the histological study of the hepatopancreas in Helix aspersa treated with ginger for a period of 15 days after stopping treatment with thiamethoxam has shown a partial regeneration of hepatopancreatic tissue snails treated with all concentrations of thiamethoxam and especially in the intertubular connective tissue of the wall and hepatopancreatic digestive tubules. Finally, we can conclude that monitoring the effect of the insecticide thiamethoxam showed significant alterations, however, treatment with ginger shows regeneration of damaged cells themselves much sharper at low concentration (10 mg/L).Keywords: Helix aspersa, insecticides, thiamethoxam, ginger, hepatopancreas
Procedia PDF Downloads 216896 Soil Bioremediation Monitoring Systems Powered by Microbial Fuel Cells
Authors: András Fülöp, Lejla Heilmann, Zsolt Szabó, Ákos Koós
Abstract:
Microbial fuel cells (MFCs) present a sustainable biotechnological solution to future energy demands. The aim of this study was to construct soil based, single cell, membrane-less MFC systems, operated without treatment to continuously power on-site monitoring and control systems during the soil bioremediation processes. Our Pseudomonas aeruginosa 541 isolate is an ideal choice for MFCs, because it is able to produce pyocyanin which behaves as electron-shuttle molecule, furthermore, it also has a significant antimicrobial effect. We tested several materials and structural configurations to obtain long term high power output. Comparing different configurations, a proton exchange membrane-less, 0.6 m long with 0.05 m diameter MFC tubes offered the best long-term performances. The long-term electricity production were tested from starch, yeast extract (YE), carboxymethyl cellulose (CMC) with humic acid (HA) as a mediator. In all cases, 3 kΩ external load have been used. The two best-operated systems were the Pseudomonas aeruginosa 541 containing MFCs with 1 % carboxymethyl cellulose and the MFCs with 1% yeast extract in the anode area and 35% hydrogel in the cathode chamber. The first had 3.3 ± 0.033 mW/m2 and the second had 4.1 ± 0.065 mW/m2 power density values. These systems have operated for 230 days without any treatment. The addition of 0.2 % HA and 1 % YE referred to the volume of the anode area resulted in 1.4 ± 0.035 mW/m2 power densities. The mixture of 1% starch with 0.2 % HA gave 1.82 ± 0.031 mW/m2. Using CMC as retard carbon source takes effect in the long-term bacterial survivor, thus enable the expression of the long term power output. The application of hydrogels in the cathode chamber significantly increased the performance of the MFC units due to their good water retention capacity.Keywords: microbial fuel cell, bioremediation, Pseudomonas aeruginosa, biotechnological solution
Procedia PDF Downloads 291895 Characteristics of Bio-hybrid Hydrogel Materials with Prolonged Release of the Model Active Substance as Potential Wound Dressings
Authors: Katarzyna Bialik-Wąs, Klaudia Pluta, Dagmara Malina, Małgorzata Miastkowska
Abstract:
In recent years, biocompatible hydrogels have been used more and more in medical applications, especially as modern dressings and drug delivery systems. The main goal of this research was the characteristics of bio-hybrid hydrogel materials incorporated with the nanocarrier-drug system, which enable the release in a gradual and prolonged manner, up to 7 days. Therefore, the use of such a combination will provide protection against mechanical damage and adequate hydration. The proposed bio-hybrid hydrogels are characterized by: transparency, biocompatibility, good mechanical strength, and the dual release system, which allows for gradual delivery of the active substance, even up to 7 days. Bio-hybrid hydrogels based on sodium alginate (SA), poly(vinyl alcohol) (PVA), glycerine, and Aloe vera solution (AV) were obtained through the chemical crosslinking method using poly(ethylene glycol) diacrylate as a crosslinking agent. Additionally, a nanocarrier-drug system was incorporated into SA/PVA/AV hydrogel matrix. Here, studies were focused on the release profiles of active substances from bio-hybrid hydrogels using the USP4 method (DZF II Flow-Through System, Erweka GmbH, Langen, Germany). The equipment incorporated seven in-line flow-through diffusion cells. The membrane was placed over support with an orifice of 1,5 cm in diameter (diffusional area, 1.766 cm²). All the cells were placed in a cell warmer connected with the Erweka heater DH 2000i and the Erweka piston pump HKP 720. The piston pump transports the receptor fluid via seven channels to the flow-through cells and automatically adapts the setting of the flow rate. All volumes were measured by gravimetric methods by filling the chambers with Milli-Q water and assuming a density of 1 g/ml. All the determinations were made in triplicate for each cell. The release study of the model active substance was carried out using a regenerated cellulose membrane Spectra/Por®Dialysis Membrane MWCO 6-8,000 Carl Roth® Company. These tests were conducted in buffer solutions – PBS at pH 7.4. A flow rate of receptor fluid of about 4 ml /1 min was selected. The experiments were carried out for 7 days at a temperature of 37°C. The released concentration of the model drug in the receptor solution was analyzed using UV-Vis spectroscopy (Perkin Elmer Company). Additionally, the following properties of the modified materials were studied: physicochemical, structural (FT-IR analysis), morphological (SEM analysis). Finally, the cytotoxicity tests using in vitro method were conducted. The obtained results exhibited that the dual release system allows for the gradual and prolonged delivery of the active substances, even up to 7 days.Keywords: wound dressings, SA/PVA hydrogels, nanocarrier-drug system, USP4 method
Procedia PDF Downloads 147894 Algal/Bacterial Membrane Bioreactor for Bioremediation of Chemical Industrial Wastewater Containing 1,4 Dioxane
Authors: Ahmed Tawfik
Abstract:
Oxidation of 1,4 dioxane produces metabolites by-products involving glycolaldehyde and acids that have geno- and cytotoxicity impact on microbial degradation. Thereby, the incorporation of algae with bacteria in the treatment system would eliminate and overcome the accumulation of metabolites that are utilized as a carbon source for the build-up of biomass. Therefore, the aim of the present study is to assess the potential of algae/bacteria-based membrane bioreactor (AB-MBR) for biodegradation of 1,4 dioxane-rich wastewater at a high imposed loading rate. Three identical reactors, i.e., AB-MBR1, AB-MBR2, and AB-MBR3, were operated in parallel at 1,4 dioxane loading rates of 641.7, 320.9, and 160.4 mg/L. d., and HRTs of 6.0, 12 and 24 h. respectively. The AB-MBR1 achieved 1,4 dioxane removal rate of 263.7 mg/L.d., where the residual value in the treated effluent amounted to 94.4±22.9 mg/L. Reducing the 1,4 dioxane loading rate (LR) to 320.9 mg/L.d in the AB-MBR2 maximized the removal rate efficiency of 265.9 mg/L.d., with a removal efficiency of 82.8±3.2%. The minimum value of 1,4 dioxane of 17.3±1.8 mg/L in the treated effluent of AB-MBR3 was obtained at an HRT of 24.0 h and loading rate of 160.4 mg/L.d. The mechanism of 1,4 dioxane degradation in AB-MBR was a combination of volatilization (8.03±0.6%), UV oxidation (14.1±0.9%), microbial biodegradation (49.1±3.9%) and absorption/uptake and assimilation by algae (28.8±2.%). Further, the Thioclava, Afipia, and Mycobacterium genera oxidized and produced the required enzymes for hydrolysis and cleavage of the dioxane ring into 2-hydroxy-1,4 dioxane. Moreover, the fungi, i.e., Basidiomycota and Cryptomycota, played a big role in the degradation of the 1,4 dioxane into 2-hydroxy-1,4 dioxane. Xanthobacter and Mesorhizobium were involved in the metabolism process by secreting alcohol dehydrogenase (ADH), aldehyde dehydrogenase (ALDH), and glycolate oxidase. Bacteria and fungi produced dehydrogenase (DH) for the transformation of 2-hydroxy-1,4 dioxane into 2-hydroxy-ethoxyacetaldehyde. The latter is converted into Ethylene glycol by Aldehyde hydrogenase (ALDH). Ethylene glycol is oxidized into acids using Alcohol hydrogenase (ADH). The Diatomea, Chlorophyta, and Streptophyta utilize the metabolites for biomass assimilation and produce the required oxygen for further oxidation of the dioxane and its metabolites by-products of bacteria and fungi. The major portion of metabolites (ethylene glycol, glycolic acid, and oxalic acid were removed due to uptake and absorption by algae (43±4.3%), followed by adsorption (18.4±0.9%). The volatilization and UV oxidation contribution for the degradation of metabolites were 8.7±0.7% and 12.3±0.8%, respectively. The capabilities of genera Defluviimonas, Thioclava, Luteolibacter, and Afipia. The genera of Defluviimonas, Thioclava, Luteolibacter, and Mycobacterium were grown under a high 1,4 dioxane LR of 641.7 mg/L.d. The Chlorophyta (4.1-43.6%), Streptophyta (2.5-21.7%), and Diatomea (0.8-1.4%) phyla were dominant for degradation of 1,4 dioxane. The results of this study strongly demonstrated that the bioremediation and bioaugmentation process can safely remove 1,4 dioxane from industrial wastewater while minimizing environmental concerns and reducing economic costs.Keywords: wastewater, membrane bioreactor, bacterial community, algal community
Procedia PDF Downloads 43893 Bio-Electrochemical Process Coupled with MnO2 Nanowires for Wastewater Treatment
Authors: A. Giwa, S. M. Jung, W. Fang, J. Kong, S. W. Hasan
Abstract:
MnO2 nanowires were developed as filtration media for wastewater treatment that uniquely combines several advantages. The resulting material demonstrated strong capability to remove the pollution of heavy metal ions and organic contents in water. In addition, the manufacture process of such material is practical and economical. In this work, MnO2 nanowires were integrated with the state-of-art bio-electrochemical system for wastewater treatment, to overcome problems currently encountered with organic, inorganic, heavy metal, and microbe removal, and to minimize the unit footprint (land/space occupation) at low cost. Results showed that coupling the bio-electrochemical with MnO2 resulted in very encouraging results with higher removal efficiencies of such pollutants.Keywords: bio-electrochemical, nanowires, novel, wastewater
Procedia PDF Downloads 387892 Effect of Phenolic Acids on Human Saliva: Evaluation by Diffusion and Precipitation Assays on Cellulose Membranes
Authors: E. Obreque-Slier, F. Orellana-Rodríguez, R. López-Solís
Abstract:
Phenolic compounds are secondary metabolites present in some foods, such as wine. Polyphenols comprise two main groups: flavonoids (anthocyanins, flavanols, and flavonols) and non-flavonoids (stilbenes and phenolic acids). Phenolic acids are low molecular weight non flavonoid compounds that are usually grouped into benzoic (gallic, vanillinic and protocatechuic acids) and cinnamic acids (ferulic, p-coumaric and caffeic acids). Likewise, tannic acid is an important polyphenol constituted mainly by gallic acid. Phenolic compounds are responsible for important properties in foods and drinks, such as color, aroma, bitterness, and astringency. Astringency is a drying, roughing, and sometimes puckering sensation that is experienced on the various oral surfaces during or immediately after tasting foods. Astringency perception has been associated with interactions between flavanols present in some foods and salivary proteins. Despite the quantitative relevance of phenolic acids in food and beverages, there is no information about its effect on salivary proteins and consequently on the sensation of astringency. The objective of this study was assessed the interaction of several phenolic acids (gallic, vanillinic, protocatechuic, ferulic, p-coumaric and caffeic acids) with saliva. Tannic acid was used as control. Thus, solutions of each phenolic acids (5 mg/mL) were mixed with human saliva (1:1 v/v). After incubation for 5 min at room temperature, 15-μL aliquots of the mixtures were dotted on a cellulose membrane and allowed to diffuse. The dry membrane was fixed in 50 g/L trichloroacetic acid, rinsed in 800 mL/L ethanol and stained for protein with Coomassie blue for 20 min, destained with several rinses of 73 g/L acetic acid and dried under a heat lamp. Both diffusion area and stain intensity of the protein spots were semiqualitative estimates for protein-tannin interaction (diffusion test). The rest of the whole saliva-phenol solution mixtures of the diffusion assay were centrifuged and fifteen-μL aliquots of each supernatant were dotted on a cellulose membrane, allowed to diffuse and processed for protein staining, as indicated above. In this latter assay, reduced protein staining was taken as indicative of protein precipitation (precipitation test). The diffusion of the salivary protein was restricted by the presence of each phenolic acids (anti-diffusive effect), while tannic acid did not alter diffusion of the salivary protein. By contrast, phenolic acids did not provoke precipitation of the salivary protein, while tannic acid produced precipitation of salivary proteins. In addition, binary mixtures (mixtures of two components) of various phenolic acids with gallic acid provoked a restriction of saliva. Similar effect was observed by the corresponding individual phenolic acids. Contrary, binary mixtures of phenolic acid with tannic acid, as well tannic acid alone, did not affect the diffusion of the saliva but they provoked an evident precipitation. In summary, phenolic acids showed a relevant interaction with the salivary proteins, thus suggesting that these wine compounds can also contribute to the sensation of astringency.Keywords: astringency, polyphenols, tannins, tannin-protein interaction
Procedia PDF Downloads 246891 Challenges of Management of Subaortic Membrane in a Young Adult Patient: A Case Review and Literature Review
Authors: Talal Asif, Maya Kosinska, Lucas Georger, Krish Sardesai, Muhammad Shah Miran
Abstract:
This article presents a case review and literature review focused on the challenges of managing subaortic membranes (SAM) in young adult patients with mild aortic regurgitation (AR) or aortic stenosis (AS). The study aims to discuss the diagnosis of SAM, imaging studies used for assessment, management strategies in young patients, the risk of valvular damage, and the controversy surrounding prophylactic resection in mild AR. The management of SAM in adults poses challenges due to limited treatment options and potential complications, necessitating further investigation into the progression of AS and AR in asymptomatic SAM patients. The case presentation describes a 40-year-old male with muscular dystrophy who presented with symptoms and was diagnosed with SAM. Various imaging techniques, including CT chest, transthoracic echocardiogram (TTE), and transesophageal echocardiogram (TEE), were used to confirm the presence and severity of SAM. Based on the patient's clinical profile and the absence of surgical indications, medical therapy was initiated, and regular outpatient follow-up was recommended to monitor disease progression. The discussion highlights the challenges in diagnosing SAM, the importance of imaging studies, and the potential complications associated with SAM in young patients. The article also explores the management options for SAM, emphasizing surgical resection as the definitive treatment while acknowledging the limited success rates of alternative approaches. Close monitoring and prompt intervention for complications are crucial in the management of SAM. The concluding statement emphasizes the need for further research to explore alternative treatments for SAM in young patients.Keywords: subaortic membrane, management, case report, literature review, aortic regurgitation, aortic stenosis, left ventricular outflow obstruction, guidelines, heart failure
Procedia PDF Downloads 100890 Chiral Amine Synthesis and Recovery by Using High Molecular Weight Amine Donors
Authors: Claudia Matassa, Matthias Hohne, Dominic Ormerod, Yamini Satyawali
Abstract:
Chiral amines integrate the backbone of several active pharmaceutical ingredients (APIs) used in modern medicine for the treatment of a vast range of diseases. Despite the demand, their synthesis remains challenging. Besides a range of chemicals and enzymatical methods, chiral amine synthesis using transaminases (EC 2.6.1.W) represents a useful alternative to access this important class of compounds. Even though transaminases exhibit excellent stereo and regioselectivity and the potential for high yield, the reaction suffers from a number of challenges, including the thermodynamic equilibrium, product inhibition, and low substrate solubility. In this work, we demonstrate a membrane assisted strategy for addressing these challenges. It involves the use of high molecular weight (HMW) amine donors for the transaminase-catalyzed synthesis of 4-phenyl-2-butylamine in both aqueous and organic solvent media. In contrast to common amine donors such as alanine or isopropylamine, these large molecules, provided in excess for thermodynamic equilibrium shifting, are easily retained by commercial nanofiltration membranes; thus a selective permeation of the desired smaller product amine is possible. The enzymatic transamination in aqueous media, combined with selective product removal shifted the equilibrium enhancing substrate conversion by an additional 25% compared to the control reaction. Along with very efficient amine product removal, there was undesirable loss of ketone substrate and low product concentration was achieved. The system was therefore further improved by performing the reaction in organic solvent (n-heptane). Coupling the reaction system with membrane-assisted product removal resulted in a highly concentrated and relatively pure ( > 97%) product solution. Moreover, a product yield of 60% was reached, compared to 15% without product removal.Keywords: amine donor, chiral amines, in situ product removal, transamination
Procedia PDF Downloads 154