Search results for: in vivo
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 755

Search results for: in vivo

335 Ameliorative Effect of Martynia annua Linn. on Collagen-Induced Arthritis via Modulating Cytokines and Oxidative Stress in Mice

Authors: Alok Pal Jain, Santram Lodhi

Abstract:

Martynia annua Linn. (Martyniaccae) is traditionally used in inflammation and applied locally to tuberculosis glands of camel’s neck. The leaves used topically to bites of venomous insects and wounds of domestic animals. Chemical examination of Martynia annua leaves revealed the presence of glycosides, tannins, proteins, phenols and flavonoids. The present study was aimed to evaluate the anti-arthritic activity of methanolic extract of Martynia annua leaves. Methanolic extract of Martynia annua leaves was tested by using in vivo collagen-induced arthritis mouse model to investigate the anti-rheumatoid arthritis activity. In addition, antioxidant effect of methanolic extract was determined by the estimation of antioxidants level in joint tissues. The severity of arthritis was assessed by arthritis score and edema. Levels of cytokines TNF-α and IL-6, in the joint tissue homogenate were measured using ELISA. A high dose (250 mg/kg) of methanolic extract was significantly reduced the degree of inflammation in mice as compared with reference drug. Antioxidants level and malondialdehyde (MDA) in joint tissue homogenate found significantly (p < 0.05) higher. Methanolic extract at dose of 250 mg/kg modulated the cytokines production and suppressed the oxidative stress in the mice with collagen-induced arthritis. This study suggested that Martynia annua might be alternative herbal medicine for the management of rheumatoid arthritis.

Keywords: Martynia annua, collagen, rheumatoid arthritis, antioxidants

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334 An Overview of Paclitaxel as an Anti-Cancer Agent in Avoiding Malignant Metastatic Cancer Therapy

Authors: Nasrin Hosseinzad, Ramin Ghasemi Shayan

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Chemotherapy is the most common procedure in the treatment of advanced cancers but is justsoberlyoperativeand toxic. Nevertheless, the efficiency of chemotherapy is restrictedowing to multiple drug resistance(MDR). Lately, plentiful preclinical experiments have revealedthatPaclitaxel-Curcumin could be an ultimateapproach to converse MDR and synergistically increase their efficiency. The connotationsamongst B-cell-lymphoma2(BCL-2) and multi-drug-resistance-associated-P-glycoprotein(MDR1) consequence of patients forecast the efficiency of paclitaxel-built chemoradiotherapy. There are evidences of the efficacy of paclitaxel in the treatment of surface-transmission of bladder-cell-carcinoma by manipulating bio-adhesive microspheres accomplishedthroughout measured release of drug at urine epithelium. In Genetically-Modified method, muco-adhesive oily constructionoftricaprylin, Tween 80, and paclitaxel group showed slighter toxicity than control in therapeutic dose. Postoperative chemotherapy-Paclitaxel might be more advantageous for survival than adjuvant chemo-radio-therapy, and coulddiminish postoperative complications in cervical cancer patients underwent a radical hysterectomy.HA-Se-PTX(Hyaluronic acid, Selenium, Paclitaxel) nanoparticles could observablyconstrain the proliferation, transmission, and invasion of metastatic cells and apoptosis. Furthermore, they exhibitedvast in vivo anti-tumor effect. Additionally, HA-Se-PTX displayedminor toxicity on mice-chef-organs. Briefly, HA-Se-PTX mightprogress into a respectednano-scale agentinrespiratory cancers. To sum up, Paclitaxel is considered a profitable anti-cancer drug in the treatment and anti-progress symptoms in malignant cancers.

Keywords: cancer, paclitaxel, chemotherapy, tumor

Procedia PDF Downloads 95
333 Optimization of Gastro-Retentive Matrix Formulation and Its Gamma Scintigraphic Evaluation

Authors: Swapnila V. Shinde, Hemant P. Joshi, Sumit R. Dhas, Dhananjaysingh B. Rajput

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The objective of the present study is to develop hydro-dynamically balanced system for atenolol, β-blocker as a single unit floating tablet. Atenolol shows pH dependent solubility resulting into a bioavailability of 36%. Thus, site specific oral controlled release floating drug delivery system was developed. Formulation includes novice use of rate controlling polymer such as locust bean gum (LBG) in combination of HPMC K4M and gas generating agent sodium bicarbonate. Tablet was prepared by direct compression method and evaluated for physico-mechanical properties. The statistical method was utilized to optimize the effect of independent variables, namely amount of HPMC K4M, LBG and three dependent responses such as cumulative drug release, floating lag time, floating time. Graphical and mathematical analysis of the results allowed the identification and quantification of the formulation variables influencing the selected responses. To study the gastrointestinal transit of the optimized gastro-retentive formulation, in vivo gamma scintigraphy was carried out in six healthy rabbits, after radio labeling the formulation with 99mTc. The transit profiles demonstrated that the dosage form was retained in the stomach for more than 5 hrs. The study signifies the potential of the developed system for stomach targeted delivery of atenolol with improved bioavailability.

Keywords: floating tablet, factorial design, gamma scintigraphy, antihypertensive model drug, HPMC, locust bean gum

Procedia PDF Downloads 252
332 Development and Validation of High-Performance Liquid Chromatography Method for the Determination and Pharmacokinetic Study of Linagliptin in Rat Plasma

Authors: Hoda Mahgoub, Abeer Hanafy

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Linagliptin (LNG) belongs to dipeptidyl-peptidase-4 (DPP-4) inhibitor class. DPP-4 inhibitors represent a new therapeutic approach for the treatment of type 2 diabetes in adults. The aim of this work was to develop and validate an accurate and reproducible HPLC method for the determination of LNG with high sensitivity in rat plasma. The method involved separation of both LNG and pindolol (internal standard) at ambient temperature on a Zorbax Eclipse XDB C18 column and a mobile phase composed of 75% methanol: 25% formic acid 0.1% pH 4.1 at a flow rate of 1.0 mL.min-1. UV detection was performed at 254nm. The method was validated in compliance with ICH guidelines and found to be linear in the range of 5–1000ng.mL-1. The limit of quantification (LOQ) was found to be 5ng.mL-1 based on 100µL of plasma. The variations for intra- and inter-assay precision were less than 10%, and the accuracy values were ranged between 93.3% and 102.5%. The extraction recovery (R%) was more than 83%. The method involved a single extraction step of a very small plasma volume (100µL). The assay was successfully applied to an in-vivo pharmacokinetic study of LNG in rats that were administered a single oral dose of 10mg.kg-1 LNG. The maximum concentration (Cmax) was found to be 927.5 ± 23.9ng.mL-1. The area under the plasma concentration-time curve (AUC0-72) was 18285.02 ± 605.76h.ng.mL-1. In conclusion, the good accuracy and low LOQ of the bioanalytical HPLC method were suitable for monitoring the full pharmacokinetic profile of LNG in rats. The main advantages of the method were the sensitivity, small sample volume, single-step extraction procedure and the short time of analysis.

Keywords: HPLC, linagliptin, pharmacokinetic study, rat plasma

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331 Rapid Mitochondrial Reactive Oxygen Species Production Precedes NF-κB Activation and Pro-inflammatory Responses in Macrophages

Authors: Parinaz Tavakoli Zaniani, Dimitrios Balomenos

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Mitochondrial reactive oxygen species (mROS) play a crucial role in macrophage pro-inflammatory activation, although a detailed understanding of the mechanism and kinetics by which mROS drive signaling molecules is still lacking. In general, it is thought that NF-κB activation drives mROS and general ROS production. Here, We performed a detailed kinetic analysis of mROS production during macrophage activation. We found early mROS generation after LPS (lipopolysaccharide) stimulation. Remarkably as early as 5 minutes, mROS signaling promoted initial NF-κB, MAPK activation and pro-inflammatory cytokine production, as established through inhibition or quenching of mROS. On the contrary, NF-κB inhibition had no effect on mROS production. Our findings point to a mechanism by which mROS increase TRAF-6 ubiquitination and, thus NF-κB activity. mROS inhibition reduced LPS-induced lethality in an in vivo septic shock model by controlling pro-inflammatory cytokine production. Overall, our research provides novel insights into the role of mROS as a primary messenger in the pathway of macrophage and as a regulator of inflammatory responses. We found that early mROS production promotes initial NF-κB, and MAPK activation by regulating TRAF-6 ubiquitination and that mROS inhibition can reduce LPS-induced inflammatory cytokines and lethality in a septic shock model. These findings might lead to novel immunotherapeutic strategies targeting early mROS production and control of extreme inflammation in the context of sepsis and other inflammatory diseases.

Keywords: mitochondria, reactive oxygen species, nuclear factor κB, lipopolysaccharide, macrophages

Procedia PDF Downloads 45
330 Effect of Clerodendrum Species on Oxidative Stress with Possible Implication in Alleviating Carcinogenesis

Authors: Somit Dutta, Pallab Kar, Arnab Kumar Chakraborty, Arnab Sen, Tapas Kumar Chaudhuri

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In the present study three species of Clerodendrum; Clerodendrum indicum, Volkameria inermis and Clerodendrum colebrookianum were used to investigate the possible activity against oxidative stress. A detailed in-vivo and in-vitro antioxidant profiling, directly associated with inflammation-related carcinogenesis, has been executed with a motive to evaluate the free radical scavenging activity of Clerodendrum extract. Measurement of cell viability and ROS generation in HEK-293 (Human Embryonic Kidney Cell Line) cells was also estimated. The immune cell proliferative properties (MTT) and in-vitro assay for evaluation of their antioxidant activities including hydroxyl radical, nitric oxide, singlet oxygen, peroxinitrate and hydrogen peroxide, etc. were investigated. GC-MS and FTIR analyses have been performed to identify the active biological compounds. These active biological compounds were further studied to assess their potential medicinal properties, aided by molecular docking and interaction analysis between the active compounds and different proteins related to oxidative stress leading to progression of carcinogenesis. The research article clearly demonstrates the role of ROS in various phases of carcinogenesis. Therefore, the antioxidant and free radical scavenging capacity of all the Clerodendrum species might prove beneficial for the immune system. It might be concluded that this plant species offers great promise for cancer prevention and therapy due to the presence of several bioactive compounds and potent antioxidant capacity of C. colebrookianum.

Keywords: antioxidant, cancer, oxidative stress, reactive oxygen species (ROS)

Procedia PDF Downloads 255
329 Evaluation of Compressive Mechanical Properties of the Radial Bone Defect Treated with Selected Bone Graft Substitute Materials in Rabbit

Authors: Omid Gholipoor Bashiri, Ghafur Mosavi, Aliasghar Behnamghader, Seyed Mahmood Rabiee

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Objective: To determine the effect of selected bone graft on the compression properties of radial bone in rabbit. Design-Experimental in vivo study. Animals: A total of 45 adult male New Zealand white rabbits. Procedures: The rabbits were anesthetized and a one-cm-full thickness piece of radial bone was removed using oscillating saw in the all rabbit. The rabbits were divided into 5 groups on the basis of the material used to fill the bone defect: group 1: the paste of bone cement calcium phosphate; group II: the paste of calcium phosphate mixture with type I collagen; group III: tricalcium phosphate mixed with hydroxyapatite (TCP & HP) with 5% porosity; group IV: the same scaffold as group III with 10% porosity; and group V: the same scaffold as group III and IV with 20% porosity, with 9 rabbits in each group. Subsequently subdivided into 3 subgroups of 3 rabbits each. Results: There was a significant increase in compression properties of radial bone in the group II and V in 2nd and 3rd months as compared with groups I, III and IV. The mean endurable crack-strength in group II and V were slightly higher than that of normal radius (P<0.05). Conclusion and clinical relevance: Application of calcium phosphate paste with type I collagen and scaffold of tricalcium phosphate with hydroxyapatite having 20% porosity indicated to have positive effect in integral formation of qualitative callus at the site of fracture and early re-organization of callus to regain mechanical strength too.

Keywords: calcium phosphate, tricalcium phosphate, hydroxyapatite, radial bone, compressive properties, porosity, type i collagen, rabbit

Procedia PDF Downloads 417
328 Reconstruction Spectral Reflectance Cube Based on Artificial Neural Network for Multispectral Imaging System

Authors: Iwan Cony Setiadi, Aulia M. T. Nasution

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The multispectral imaging (MSI) technique has been used for skin analysis, especially for distant mapping of in-vivo skin chromophores by analyzing spectral data at each reflected image pixel. For ergonomic purpose, our multispectral imaging system is decomposed in two parts: a light source compartment based on LED with 11 different wavelenghts and a monochromatic 8-Bit CCD camera with C-Mount Objective Lens. The software based on GUI MATLAB to control the system was also developed. Our system provides 11 monoband images and is coupled with a software reconstructing hyperspectral cubes from these multispectral images. In this paper, we proposed a new method to build a hyperspectral reflectance cube based on artificial neural network algorithm. After preliminary corrections, a neural network is trained using the 32 natural color from X-Rite Color Checker Passport. The learning procedure involves acquisition, by a spectrophotometer. This neural network is then used to retrieve a megapixel multispectral cube between 380 and 880 nm with a 5 nm resolution from a low-spectral-resolution multispectral acquisition. As hyperspectral cubes contain spectra for each pixel; comparison should be done between the theoretical values from the spectrophotometer and the reconstructed spectrum. To evaluate the performance of reconstruction, we used the Goodness of Fit Coefficient (GFC) and Root Mean Squared Error (RMSE). To validate reconstruction, the set of 8 colour patches reconstructed by our MSI system and the one recorded by the spectrophotometer were compared. The average GFC was 0.9990 (standard deviation = 0.0010) and the average RMSE is 0.2167 (standard deviation = 0.064).

Keywords: multispectral imaging, reflectance cube, spectral reconstruction, artificial neural network

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327 A Validated High-Performance Liquid Chromatography-UV Method for Determination of Malondialdehyde-Application to Study in Chronic Ciprofloxacin Treated Rats

Authors: Anil P. Dewani, Ravindra L. Bakal, Anil V. Chandewar

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Present work demonstrates the applicability of high-performance liquid chromatography (HPLC) with UV detection for the determination of malondialdehyde as malondialdehyde-thiobarbituric acid complex (MDA-TBA) in-vivo in rats. The HPLC-UV method for MDA-TBA was achieved by isocratic mode on a reverse-phase C18 column (250mm×4.6mm) at a flow rate of 1.0mLmin−1 followed by UV detection at 278 nm. The chromatographic conditions were optimized by varying the concentration and pH followed by changes in percentage of organic phase optimal mobile phase consisted of mixture of water (0.2% Triethylamine pH adjusted to 2.3 by ortho-phosphoric acid) and acetonitrile in ratio (80:20 % v/v). The retention time of MDA-TBA complex was 3.7 min. The developed method was sensitive as limit of detection and quantification (LOD and LOQ) for MDA-TBA complex were (standard deviation and slope of calibration curve) 110 ng/ml and 363 ng/ml respectively. The method was linear for MDA spiked in plasma and subjected to derivatization at concentrations ranging from 100 to 1000 ng/ml. The precision of developed method measured in terms of relative standard deviations for intra-day and inter-day studies was 1.6–5.0% and 1.9–3.6% respectively. The HPLC method was applied for monitoring MDA levels in rats subjected to chronic treatment of ciprofloxacin (CFL) (5mg/kg/day) for 21 days. Results were compared by findings in control group rats. Mean peak areas of both study groups was subjected for statistical treatment to unpaired student t-test to find p-values. The p value was < 0.001 indicating significant results and suggesting increased MDA levels in rats subjected to chronic treatment of CFL of 21 days.

Keywords: MDA, TBA, ciprofloxacin, HPLC-UV

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326 Iron Response Element-mRNA Binding to Iron Response Protein: Metal Ion Sensing

Authors: Mateen A. Khan, Elizabeth J. Theil, Dixie J. Goss

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Cellular iron homeostasis is accomplished by the coordinated regulated expression of iron uptake, storage, and export. Iron regulate the translation of ferritin and mitochondrial aconitase iron responsive element (IRE)-mRNA by interaction with an iron regulatory protein (IRPs). Iron increases protein biosynthesis encoded in iron responsive element. The noncoding structure IRE-mRNA, approximately 30-nt, folds into a stem loop to control synthesis of proteins in iron trafficking, cell cycling, and nervous system function. Fluorescence anisotropy measurements showed the presence of one binding site on IRP1 for ferritin and mitochondrial aconitase IRE-mRNA. Scatchard analysis revealed the binding affinity (Kₐ) and average binding sites (n) for ferritin and mitochondrial aconitase IRE-mRNA were 68.7 x 10⁶ M⁻¹ and 9.2 x 10⁶ M⁻¹, respectively. In order to understand the relative importance of equilibrium and stability, we further report the contribution of electrostatic interactions in the overall binding of two IRE-mRNA with IRP1. The fluorescence quenching of IRP1 protein was measured at different ionic strengths. The binding affinity of IRE-mRNA to IRP1 decreases with increasing ionic strength, but the number of binding sites was independent of ionic strength. Such results indicate a differential contribution of electrostatics to the interaction of IRE-mRNA with IRP1, possibly related to helix bending or stem interactions and an overall conformational change. Selective destabilization of ferritin and mitochondrial aconitase RNA/protein complexes as reported here explain in part the quantitative differences in signal response to iron in vivo and indicate possible new regulatory interactions.

Keywords: IRE-mRNA, IRP1, binding, ionic strength

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325 Preclinical Evidence of Pharmacological Effect from Medicinal Hemp

Authors: Muhammad nor Farhan Sa'At, Xin Y. Lim, Terence Y. C. Tan, Siti Hajar M. Rosli, Syazwani S. Ali, Ami F. Syed Mohamed

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INTRODUCTION: Hemp (Cannabis sativa subsp. sativa), commonly used for industrial purposes, differs from marijuana by containing lower levels of delta-9-tetrahydronannabidiol- the principal psychoactive constituent in cannabis. Due to its non-psychoactive nature, there has been growing interest in hemp’s therapeutic potential, which has been investigated through pre-clinical and clinical study modalities. OBJECTIVE: To provide an overview of the current landscape of hemp research, through recent scientific findings specific to the pharmacological effects of the medicinal hemp plant and its derived compounds. METHODS: This review was conducted through a systematic search strategy according to the preferred reporting items for systematic review and meta-analysis-ScR (PRISMA-ScR) checklist on electronic databases including MEDLINE, OVID (OVFT, APC Journal Club, EBM Reviews), Cochrane Library Central and Clinicaltrials.gov. RESULTS: From 65 primary articles reviewed, there were 47 pre-clinical studies related to medicinal hemp. Interestingly, the hemp derivatives showed several potential activities such as anti-oxidative, anti-hypertensive, anti-inflammatory, anti-diabetic, anti-neuroinflammatory, anti-arthritic, anti-acne, and anti-microbial activities. Renal protective effects and estrogenic properties were also exhibited in vitro. CONCLUSION: Medicinal hemp possesses various pharmacological effects tested in vitro and in vivo. Information provided in this review could be used as tool to strengthen the study design of future clinical trial research.

Keywords: Preclinical, Herbal Medicine, Hemp, Cannabis

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324 Culturing of Bovine Pre-Compacted Morlae in TCM-199 and Baf in a Standard 5% CO2 Laboratory Incubator and in the Vagina of a Goat Doe

Authors: Daniel M. Barry

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Since more than half a century ago, attempts have been made to culture cells and embryos outside the body (in vitro or ex vivo). This was done with different culture media and in various “incubators”. In the present study two different culture media were used: a standard TCM-199 culture medium and first trimester amniotic fluid (BAF) collected sterilely from pregnant cows after slaughter. Two different culture conditions were also investigated, the standard laboratory CO2 incubator versus culturing bovine embryos in the vagina of a goat doe. Two experiments were done: Firstly the permeability of different receptacles to CO2 gas was analyzed for possible culture in the vagina. Four-well plates and straws were used to incubate TCM-199 and BAF for a period of 120 h in the presence or absence of 5% CO2 gas. The pH values were measured and recorded every 24 h. In the second experiment pre-compacted morula stage bovine embryos were cultured in the above culture media in sealed 0.25 mL straws in a standard laboratory incubator and in the vagina of a goat doe. Evaluation was done on (1) stage of development and (2) number of blastomeres after 96 h of culture. In the first experiment it was shown that the CO2 gas diffused out of the 4-well plate as well as through the wall of the straws in the absence of CO2 gas, while in the presence of CO2 the pH of both media stabilized between 7.3 and 7.5. This meant that the semen straws were permeable to CO2 gas and could therefore be used as receptacles for culturing early stage bovine embryos. In the second experiment no statistical differences (p>0.05) were found in the number of pre-compacted bovine embryos that developed to the blastocyst stage, or the hatched blastocyst stage, neither for the culture medium used, or the method of culturing in the two incubators. Neither was there any difference (p>0.05) in the number of blastomeres that developed at the blastocyst stage between the two types of incubators. The bovine embryos tended to develop more blastomeres when cultured in BAF than when cultured in TCM-199 in both the standard laboratory incubator and when using the vagina of a goat doe as an incubator.

Keywords: alternative culture, bovine embryos, vagina, bovine amniotic fluid, incubator

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323 Sequential Release of Dual Drugs Using Thermo-Sensitive Hydrogel for Tumor Vascular Inhibition and to Enhance the Efficacy of Chemotherapy

Authors: Haile F. Darge, Hsieh C. Tsai

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The tumor microenvironment affects the therapeutic outcomes of cancer disease. In a malignant tumor, overexpression of vascular endothelial growth factor (VEGF) provokes the production of pathologic vascular networks. This results in a hostile tumor environment that hinders anti-cancer drug activities and profoundly fuels tumor progression. In this study, we develop a strategy of sequential sustain release of the anti-angiogenic drug: Bevacizumab(BVZ), and anti-cancer drug: Doxorubicin(DOX) which had a synergistic effect on cancer treatment. Poly (D, L-Lactide)- Poly (ethylene glycol) –Poly (D, L-Lactide) (PDLLA-PEG-PDLLA) thermo-sensitive hydrogel was used as a vehicle for local delivery of drugs in a single platform. The in vitro release profiles of the drugs were investigated and confirmed a relatively rapid release of BVZ (73.56 ± 1.39%) followed by Dox (61.21 ± 0.62%) for a prolonged period. The cytotoxicity test revealed that the copolymer exhibited negligible cytotoxicity up to 2.5 mg ml-1 concentration on HaCaT and HeLa cells. The in vivo study on Hela xenograft nude mice verified that hydrogel co-loaded with BVZ and DOX displayed the highest tumor suppression efficacy for up to 36 days with pronounce anti-angiogenic effect of BVZ and with no noticeable damage on vital organs. Therefore, localized co-delivery of anti-angiogenic drug and anti-cancer drugs by the hydrogel system may be a promising approach for enhanced chemotherapeutic efficacy in cancer treatment.

Keywords: anti-angiogenesis, chemotherapy, controlled release, thermo-sensitive hydrogel

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322 Bifunctional Electrospun Fibers Based on Poly(Lactic Acid)/Calcium Oxide Nanocomposites as a Potential Scaffold for Bone Tissue Engineering

Authors: Daniel Canales, Fabián Alvarez, Pablo Varela, Marcela Saavedra, Claudio García, Paula Zapata

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Calcium oxide nanoparticles (n-CaO) ca. 8 nm were obtained from eggshell waste. The n-CaO was incorporated into Poly(lactic acid) PLA matrix in 10 and 20 wt.% of filler content by electrospinning process to obtain PLA/n-CaO nanocomposite fibers as a potential use in scaffold for bone tissue regeneration. The fibers morphology and diameter were homogeneity, the PLA had a diameter of 2.2 ± 0.8 µm and, with the nanoparticles incorporation (20wt.%), reached ca. 2.9 ± 0.9 µm. The PLA/n-CaO nanocomposites fibers showed in vitro bioactivity, capable of inducing the precipitation of hydroxyapatite (HA) layer in the fiber surface after 7 days in Simulated Body Solution (SBF). The biocidal and biological properties of PLA/n-Cao with 20 wt.% were evaluated, showing a 30% reduction in bacterial viability against S. aureus and 11% for E. coli after 6 hours of bacterial suspensions exposure. Furthermore, the fibers did not show a cytotoxic effect on the bone marrow ST-2 cell line, permitting the cell adhesion and proliferation in Roswell Park Memorial Institute medium (RPMI). The PLA/n-CaO with 20 wt.% of nanoparticles showed a higher capacity to promote the osteogenic differentiation, significantly increasing the alkaline phosphatase (ALP) expression after 7 days compared to PLA and cell control. The in vivo analysis corroborated the biocompatibility of scaffolds prepared, the presence of n-CaO in PLA reduced the formation of fibrous encapsulation of the material improve the healing process.

Keywords: electrospun scaffolds, PLA based nanocomposites, calcium oxide nanoparticles, bioactive materials, tissue engineering

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321 Collagen Scaffold Incorporated with Macrotyloma uniflorum Plant Extracts as a–Burn/Wound Dressing Material, in Vitro and in Vivo Evaluation

Authors: Thangavelu Muthukumar, Thotapalli Parvathaleswara Sastry

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Collagen is the most abundantly available connective tissue protein, which is being used as a biomaterial for various biomedical applications. Presently, fish wastes are disposed improperly which is causing serious environmental pollution resulting in offensive odour. Fish scales are promising source of Type I collagen. Medicinal plants have been used since time immemorial for treatment of various ailments of skin and dermatological disorders especially cuts, wounds, and burns. Developing biomaterials from the natural sources which are having wound healing properties within the search of a common man is the need of hour, particularly in developing and third world countries. With these objectives in view we have developed a wound dressing material containing fish scale collagen (FSC) incorporated with Macrotyloma uniflorum plant extract (PE). The wound dressing composite was characterized for its physiochemical properties using conventional methods. SEM image revealed that the composite has fibrous and porous surface which helps in transportation of oxygen as well as absorbing wound fluids. The biomaterial has shown 95% biocompatibility with required mechanical strength and has exhibited antimicrobial properties. This biomaterial has been used as a wound dressing material in experimental wounds of rats. The healing pattern was evaluated by macroscopic observations, panimetric studies, biochemical, histopathological observations. The results showed faster healing pattern in the wounds treated with CSPE compared to the other composites used in this study and untreated control. These experiments clearly suggest that CSPE can be used as wound/burn dressing materials.

Keywords: collagen, wound dressing, Macrotyloma uniflorum, burn dressing

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320 Remote Controlled of In-Situ Forming Thermo-sensitive Hydrogel Nanocomposite for Hyperthermia Therapy Application: Synthesis and Characterizations

Authors: Elbadawy A. Kamoun

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Magnetically responsive hydrogel nanocomposite (NCH) based on composites of superparamagnetic of Fe3O4 nano-particles and temperature responsive hydrogel matrices were developed. The nanocomposite hydrogel system based on the temperature sensitive N-isopropylacrylamide hydrogels crosslinked by poly(ethylene glycol)-400 dimethacrylate (PEG400DMA) incorporating with chitosan derivative, was synthesized and characterized. Likewise, the NCH system was synthesized by visible-light free radical photopolymerization, using carboxylated camphorquinone-amine system to avoid the common risks of the use of UV-light especially in hyperthermia treatment. Superparamagnetic of iron oxide nanoparticles were introduced into the hydrogel system by polymerizing mixture technique and monomer solution. FT-IR with Raman spectroscopy and Wide angle-XRD analysis were utilized to verify the chemical structure of NCH and exfoliation reaction for nanoparticles, respectively. Additionally, morphological structure of NCH was investigated using SEM and TEM photographs. The swelling responsive of the current nanocomposite hydrogel system with different crosslinking conditions, temperature, magnetic field efficiency, and the presence effect of magnetic nanoparticles were evaluated. Notably, hydrolytic degradation of this system was proved in vitro application. While, in-vivo release profile behavior is under investigation nowadays. Moreover, the compatibility and cytotoxicity tests were previously investigated in our studies for photoinitiating system. These systems show promised polymeric material candidate devices and are expected to have a wide applicability in various biomedical applications as mildly.

Keywords: hydrogel nanocomposites, tempretaure-responsive hydrogel, superparamagnetic nanoparticles, hyperthermia therapy

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319 Evaluation of the Biological Activities of Chrysin as an Important Perspective in the Treatment of Infectious and Cancer Diseases

Authors: Sajjad Jafari, Reza Akbari

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Background and Aim: Chrysin, a flavonoid compound found in medicinal plants, honey, and propolis, has potential biological activities that make it an important perspective in the treatment of infectious and cancer diseases. The aim of this review study is to evaluate the biological activities of chrysin in the treatment of infectious and cancer diseases. Material and Methods: The present study is a review study that searched reputable scientific databases such as PubMed, Google Scholar, Scopus, and Web of Science from 2000 to 2023 using keywords such as antimicrobial, antifungal, chrysin, anticancer, antioxidants, and infectious diseases. The researchers examined 25 articles to determine the biological activities of chrysin. Results: Chrysin has high inhibitory or lethal activities on gram-positive and gram-negative bacteria, including Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Bacillus subtilis, and Enterococcus faeces. It also has anti-biofilm effects and antifungal effects on strains such as Aspergillus niger and Candida albicans. Chrysin also has anticancer effects on various cancers, including colorectal cancer, pancreatic cancer, breast cancer, and MCF-7 cancer, which have been confirmed in vitro and in vivo. Conclusion: Chrysin has the potential as an important therapeutic option in the treatment of infectious and cancer diseases. Its high antimicrobial and anticancer activities, combined with its low toxicity in nanoparticle form, make it a promising candidate for further clinical trials. The production of anti-microbial and anti-cancer drugs from natural substances, such as chrysin, is a valuable contribution to the field of medicine.

Keywords: chrysin, antimicrobial, anticancer, infectious diseases

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318 Indenyl and Allyl Palladates: Synthesis, Bonding, and Anticancer Activity

Authors: T. Scattolin, E. Cavarzerani, F. Visentin, F. Rizzolio

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Organopalladium compounds have recently attracted attention for their high stability even under physiological conditions and, above all, for their remarkable in vitro cytotoxicity towards cisplatin-resistant cell lines. Among the organopalladium derivatives, those bearing at least one N-heterocyclic carbene ligand (NHC) and the Pd(II)-η³-allyl fragment have exhibited IC₅₀ values in the micro and sub-micromolar range towards several cancer cell lines in vitro and in some cases selectivity towards cancerous vs. non-tumorigenic cells. Herein, a selection of allyl and indenyl palladates were synthesized using a solvent-free method consisting of grinding the corresponding palladium precursors with different saturated and unsaturated azolium salts. All compounds have been fully characterized by NMR, XRD and elemental analyses. The intramolecular H, Cl interaction has been elucidated and quantified using the Voronoi Deformation Density scheme. Most of the complexes showed excellent cytotoxicity towards ovarian cancer cell lines, with I₅₀ values comparable to or even lower than cisplatin. Interestingly, the potent anticancer activity was also confirmed in a high-serous ovarian cancer (HGSOC) patient-derived tumoroid, with a clear superiority of this class of compounds over classical platinum-based agents. Finally, preliminary enzyme inhibition studies of the synthesized palladate complexes against the model TrxR show that the compounds have high activity comparable to or even higher than auranofin and classical Au(I) NHC complexes. Based on such promising data, further in vitro and in vivo experiments and in-depth mechanistic studies are ongoing in our laboratories.

Keywords: anticancer activity, palladium complexes, organoids, indenyl and allyl ligands

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317 Mechanical Properties of Young and Senescence Fibroblast Cells Using Passive Microrheology

Authors: Samira Khalaji, , Fenneke Klein Jan, Kay-E. Gottschalk, Eugenia Makrantonaki, Karin Scharffetter-Kochanek

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Biological aging is a multi-dimensional process that takes place over a whole range of scales from the nanoscopic alterations within individual cells, over transformations in tissues and organs and to changes of the whole organism. On the single cell level, aging involves mutation of genes, differences in gene expression levels as well as altered posttranslational modifications of proteins. A variety of proteins is affected, including proteins of the cell cytoskeleton and migration machinery. Previous work quantified the expression of cytoskeleton proteins on the gene and protein levels in senescent and young fibroblasts. Their results show that senescent skin fibroblasts have an upregulated expression of the intermediate filament (IF) protein vimentin in contrast to actin and tubulin, which are downregulated. IFs play an important role in providing mechanical stability of cells. However, the mechanical properties of IFs depending on cellular senescence or age of the donor has not been studied so far. Hence, we employed passive microrheology on primary human dermal fibroblasts from female donors with age of 28 years (young) and 86 years (old) as model of in vivo aging and human normal dermal fibroblast from 11-year old male with CPD 17-35 (young) and CPD 58-59 (senescence) as a model of in vitro replicative senescence. In contrast to the expectations, our primary results show no significant differences in the viscoelastic properties of fibroblasts depending on age of the donor or cellular replicative senescence.

Keywords: aging, cytoskeleton, fibroblast, mechanical properties

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316 Insight into the Binding Theme of CA-074Me to Cathepsin B: Molecular Dynamics Simulations and Scaffold Hopping to Identify Potential Analogues as Anti-Neurodegenerative Diseases

Authors: Tivani Phosa Mashamba-Thompson, Mahmoud E. S. Soliman

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To date, the cause of neurodegeneration is not well understood and diseases that stem from neurodegeneration currently have no known cures. Cathepsin B (CB) enzyme is known to be involved in the production of peptide neurotransmitters and toxic peptides in neurodegenerative diseases (NDs). CA-074Me is a membrane-permeable irreversible selective cathepsin B (CB) inhibitor as confirmed by in vivo studies. Due to the lack of the crystal structure, the binding mode of CA-074Me with the human CB at molecular level has not been previously reported. The main aim of this study is to gain an insight into the binding mode of CB CA-074Me to human CB using various computational tools. Herein, molecular dynamics simulations, binding free energy calculations and per-residue energy decomposition analysis were employed to accomplish the aim of the study. Another objective was to identify novel CB inhibitors based on the structure of CA-074Me using fragment based drug design using scaffold hoping drug design approach. Results showed that two of the designed ligands (hit 1 and hit 2) were found to have better binding affinities than the prototype inhibitor, CA-074Me, by ~2-3 kcal/mol. Per-residue energy decomposition showed that amino acid residues Cys29, Gly196, His197 and Val174 contributed the most towards the binding. The Van der Waals binding forces were found to be the major component of the binding interactions. The findings of this study should assist medicinal chemist towards the design of potential irreversible CB inhibitors.

Keywords: cathepsin B, scaffold hopping, docking, molecular dynamics, binding-free energy, neurodegerative diseases

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315 Osteogenesis in Thermo-Sensitive Hydrogel Using Mesenchymal Stem Cell Derived from Human Turbinate

Authors: A. Reum Son, Jin Seon Kwon, Seung Hun Park, Hai Bang Lee, Moon Suk Kim

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These days, stem cell therapy is focused on for promising source of treatment in clinical human disease. As a supporter of stem cells, in situ-forming hydrogels with growth factors and cells appear to be a promising approach in tissue engineering. To examine osteogenic differentiation of hTMSCs which is one of mesenchymal stem cells in vivo in an injectable hydrogel, we use a methoxy polyethylene glycol-polycaprolactone blockcopolymer (MPEG-PCL) solution with osteogenic factors. We synthesized MPEG-PCL hydrogel and measured viscosity to check sol-gel transition. In order to demonstrate osteogenic ability of hTMSCs, we conducted in vitro osteogenesis experiment. Then, to confirm the cell cytotoxicity, we performed WST-1 with hTMSCs and MPEG-PCL. As the result of in vitro experiment, we implanted cell and hydrogel mixture into animal model and checked degree of osteogenesis with histological analysis and amount of expression genes. Through these experimental data, MPEG-PCL hydrogel has sol-gel transition in temperature change and is biocompatible with stem cells. In histological analysis and gene expression, hTMSCs are very good source of osteogenesis with hydrogel and will use it to tissue engineering as important treatment method. hTMSCs could be a good adult stem cell source for usability of isolation and high proliferation. When hTMSCs are used as cell therapy method with in situ-formed hydrogel, they may provide various benefits like a noninvasive alternative for bone tissue engineering applications.

Keywords: injectable hydrogel, stem cell, osteogenic differentiation, tissue engineering

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314 Culture of Primary Cortical Neurons on Hydrophobic Nanofibers Induces the Formation of Organoid-Like Structures

Authors: Nick Weir, Robert Stevens, Alan Hargreaves, Martin McGinnity, Chris Tinsley

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Hydrophobic materials have previously demonstrated the ability to elevate cell-cell interactions and promote the formation of neural networks whilst aligned nanofibers demonstrate the ability to induce extensive neurite outgrowth in an aligned manner. Hydrophobic materials typically elicit an immune response upon implantation and thus materials used for implantation are typically hydrophilic. Poly-L-lactic acid (PLLA) is a hydrophobic, non-immunogenic, FDA approved material that can be electrospun to form aligned nanofibers. Primary rat cortical neurons cultured for 10 days on aligned PLLA nanofibers formed 3D cell clusters, approximately 800 microns in diameter. Neurites that extended from these clusters were highly aligned due to the alignment of the nanofibers they were cultured upon and fasciculation was also evident. Plasma treatment of the PLLA nanofibers prior to seeding of cells significantly reduced the hydrophobicity and abolished the cluster formation and neurite fasciculation, whilst reducing the extent and directionality of neurite outgrowth; it is proposed that hydrophobicity induces the changes to cellular behaviors. Aligned PLLA nanofibers induced the formation of a structure that mimics the grey-white matter compartmentalization that is observed in vivo and thus represents a step forward in generating organoids or biomaterial-based implants. Upon implantation into the brain, the biomaterial architectures described here may provide a useful platform for both brain repair and brain remodeling initiatives.

Keywords: hydrophobicity, nanofibers, neurite fasciculation, neurite outgrowth, PLLA

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313 Biodegradable and Bioactive Scaffold for Bone Tissue Engineering

Authors: A. M. Malagon Escandon, J. A. Arenas Alatorre, C. P. Chaires Rosas, N. A. Vazquez Torres, B. Hernandez Tellez, G. Pinon Zarate, M. Herrera Enriquez, A. E. Castell Rodriguez

Abstract:

The current approach to the treatment of bone defects involves the use of scaffolds that provide a biological and mechanically stable niche to favor tissue repair. Despite the significant progress in the field of bone tissue engineering, several main problems associated are attributed to giving a low biodegradation degree, does not promote osseointegration and regeneration, if the bone is not healing as well as expected or fails to heal, will not be given a proper ossification or new bone formation. The actual approaches of bone tissue regeneration are directed to the use of decellularized native extracellular matrices, which are able of retain their own architecture, mechanic properties, biodegradability and promote new bone formation because they are capable of conserving proteins and other factors that are founded in physiological concentrations. Therefore, we propose an extracellular matrix-based bioscaffolds derived from bovine cancellous bone, which is processed by decellularization, demineralization, and hydrolysis of the collagen protein, these protocols have been successfully carried out in other organs and tissues; the effectiveness of its biosafety has also been previously evaluated in vivo and Food and Drug Administration (FDA) approved. In the specific case of bone, a more complex treatment is needed in comparison with other organs and tissues because is necessary demineralization and collagen denaturalization. The present work was made in order to obtain a temporal scaffold that succeed in degradation in an inversely proportional way to the synthesis of extracellular matrix and the maturation of the bone by the cells of the host.

Keywords: bioactive, biodegradable, bone, extracellular matrix-based bioscaffolds, stem cells, tissue engineering

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312 Screening of Lactobacilli and Bifidobacteria from Bangladeshi Indigenous Poultry for Their Potential Use as Probiotics

Authors: K. B. M. Islam, Syeeda Shiraj-Um-Mahmuda, Afroj Jahan, A. A. Bhuiyan

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In Bangladesh, the use of imported probiotics in poultry is gradually being increased. But surprisingly, no probiotic bacteria have been isolated yet in Bangladesh despite the existence of scavenging native poultry as potential source that is seemingly more resistant to GIT infection as well as other diseases. Therefore, the study was undertaken to isolate, identify and characterize the potential probiotic Lactobacillus and Bifidobacteria strains from Bangladeshi indigenous poultry, and to evaluate their suitability to use in poultry industry. Crop and cecal samples from 61 healthy indigenous birds were used to isolate potential probiotics strains following conventional cultural methods. A total of 216 isolates were identified following physical, biochemical and molecular methods that belonged to the genus Lactobacillus and Bifidobacteria. An auto-aggregation test was performed for 180 and 136 isolated lactobacilli and bifidobacteria strains, respectively. Twelve lactobacilli isolates and 7 bifidobacteria isolates were selected because of their convenient aggregation. In vitro tests including antibacterial activity, resistance to low pH, hemolytic activities etc. were performed for evaluation of probiotic potential of each strain. Under the in vitro conditions and with respects to the probiotic traits, three lactobacilli; LS16, LS45, LS133 and two bifidobacteria, BS21 and BS90 were found to be potential probiotic strains. Thus, they are proposed to be evaluated for their in vivo probiotic properties. If the proposed strains are found suitable as the probiotics to be used in commercial poultry industry, it is expected that the local probiotics would be more beneficial and would save the huge amount of money that Bangladesh spends every year for the importation of such materials from abroad.

Keywords: Bangladeshi poultry, gut microbiota, lactic acid bacteria, scavenging chicken, GIT health

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311 Anti-Allergic Activities of Smilax Glabra Rhizome Extracts and Its Isolated Compounds

Authors: Arunporn Itharat, Kamonmas Srikwan, Srisopa Ruangnoo, Pakakrong Thongdeeying

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Background: The rhizomes of Smilax glabra (SG) has long been used in Traditional Chinese and Thai herbal medicine to treat a variety of infectious diseases and immunological disorders. Objective: To investigate the in vitro anti-allergic activities of crude extracts and pure isolated flavonoid compounds from SG by determination of inhibitory effects on antigen-induced release of β-hexosaminidase from RBL-2H3 cells. Methods: The in vitro inhibitory effects of crude aqueous and organic extracts on beta-hexosaminidase release in RBL-2H3 cells were evaluated as an in vitro indication of possible anti-allergic activity in vivo. Bioassay-guided fractionation of extracts was used to isolate flavonoid compounds from the ethanolic extracts. Results: The 95% and 50% ethanolic extracts of SG showed remarkably high anti-allergic activity, with IC50 values of 5.74 ± 2.44 and 23.54 ± 4.75 μg/ml, much higher activity than that for Ketotifen (IC50 58.90 μM). The water extract had negligible activity (IC50 > 100 μg/ml). The two isolated flavonols, Engeletin and Astilbin, showed weak anti-allergic activity, IC50 values 97.46 ± 2.04 and > 100 μg/ml, respectively. Conclusions: The 95% and 50% ethanolic extracts of SG showed strong anti-allergic activity but two flavonol constituents did not show any significant anti-allergic activity. These findings suggest that a combination of effects of various phytochemicals in crude extracts used in traditional medicine are responsible for the purported anti-allergic activity of SG herbal preparations. The plethora of constituents in crude extracts, as yet unidentified, are likely to be acting synergistically to account for the strong observed anti-allergic in vitro activity.

Keywords: Smilax glabra, anti-allergic activity, RBL-2H3 cells, flavonoid compounds

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310 Effects of a Bioactive Subfraction of Strobilanthes Crispus on the Tumour Growth, Body Weight and Haematological Parameters in 4T1-Induced Breast Cancer Model

Authors: Yusha'u Shu'aibu Baraya, Kah Keng Wong, Nik Soriani Yaacob

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Strobilanthes crispus (S. crispus), is a Malaysian herb locally known as ‘Pecah kaca’ or ‘Jin batu’ which have demonstrated potent anticancer effects in both in vitro and in vivo models. In particular, S. crispus subfraction (SCS) significantly reduced tumor growth in N-methyl-N-Nitrosourea-induced breast cancer rat model. However, there is paucity of information on the effects of SCS in breast cancer metastasis. Thus, in this study, the antimetastatic effects of SCS (100 mg/kg) was investigated following 30 days of treatment in 4T1-induced mammary tumor (n = 5) model. The response to treatment was assessed based on the outcome of the tumour growth, body weight and hematological parameters. The results demonstrated that tumor bearing mice treated with SCS (TM-S) had significant (p<0.05) reduction in the mean tumor number and tumor volume as well as tumor weight compared to the tumor bearing mice (TM), i.e. tumor untreated group. Also, there was no secondary tumor formation or tumor-associated lesions in the major organs of TM-S compared to the TM group. Similarly, comparable body weights were observed among the TM-S, normal (uninduced) mice treated with SCS and normal (untreated/control) mice (NM) groups compared to the TM group (p<0.05). Furthermore, SCS administration does not cause significant changes in the hematological parameters as compared to the NM group, which indicates no sign of anemia and toxicity related effects. In conclusion, SCS significantly inhibited the overall tumor growth and metastasis in 4T1-induced breast cancer mouse model suggesting its promising potentials as therapeutic agent for breast cancer treatment.

Keywords: 4T1-cells, breast cancer, metastasis, Strobilanthes crispus

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309 Colorimetric Measurement of Dipeptidyl Peptidase IV (DPP IV) Activity via Peptide Capped Gold Nanoparticles

Authors: H. Aldewachi, M. Hines, M. McCulloch, N. Woodroofe, P. Gardiner

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DPP-IV is an enzyme whose expression is affected in a variety of diseases, therefore, has been identified as possible diagnostic or prognostic marker for various tumours, immunological, inflammatory, neuroendocrine, and viral diseases. Recently, DPP-IV enzyme has been identified as a novel target for type II diabetes treatment where the enzyme is involved. There is, therefore, a need to develop sensitive and specific methods that can be easily deployed for the screening of the enzyme either as a tool for drug screening or disease marker in biological samples. A variety of assays have been introduced for the determination of DPP-IV enzyme activity using chromogenic and fluorogenic substrates, nevertheless these assays either lack the required sensitivity especially in inhibited enzyme samples or displays low water solubility implying difficulty for use in vivo samples in addition to labour and time-consuming sample preparation. In this study, novel strategies based on exploiting the high extinction coefficient of gold nanoparticles (GNPs) are investigated in order to develop fast, specific and reliable enzymatic assay by investigating synthetic peptide sequences containing a DPP IV cleavage site and coupling them to GNPs. The DPP IV could be detected by colorimetric response of peptide capped GNPs (P-GNPS) that could be monitored by a UV-visible spectrophotometer or even naked eyes, and the detection limit could reach 0.01 unit/ml. The P-GNPs, when subjected to DPP IV, showed excellent selectivity compared to other proteins (thrombin and human serum albumin) , which led to prominent colour change. This provided a simple and effective colorimetric sensor for on-site and real-time detection of DPP IV.

Keywords: gold nanoparticles, synthetic peptides, colorimetric detection, DPP-IV enzyme

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308 The Effect of Different Metal Nanoparticles on Growth and Survival of Pseudomonas syringae Bacteria

Authors: Omar Alhamd, Peter A. Thomas, Trevor J. Greenhough, Annette K. Shrive

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The Pseudomonas syringae species complex includes many plant pathogenic strains with highly specific interactions with varied host species and cultivars. The rapid spread of these bacteria over the last ten years has become a cause for concern. Nanoparticles have previously shown promise in microbiological action. We have therefore investigated in vitro and in vivo the effects of different types and sizes of nanoparticles in order to provide quantitative information about their effect on the bacteria. The effects of several different nanoparticles against several bacteria strains were investigated. The effect of NP on bacterial growth was studied by measuring the optical density, biochemical and nutritional tests, and transmission electron microscopy (TEM) to determine the shape and size of NP. Our results indicate that their effects varied, with either a negative or a positive impact on both bacterial and plant growth. Additionally, the methods of exposure to nanoparticles have a crucial role in accumulation, translocation, growth response and bacterial growth. The results of our studies on the behaviour and effects of nanoparticles in model plants showed. Cerium oxide (CeO₂) and silver (Ag) NP showed significant antibacterial activity against several pathogenic bacteria. It was found that titanium nanoparticles (TiO₂) can have either a negative or a positive impact, according to concentration and size. It is also thought that environmental conditions can have a major influence on bacterial growth. Studies were therefore also carried out under some environmental stress conditions to test bacterial survival and to assess bacterial virulence. All results will be presented including information about the effects of different nanoparticles on Pseudomonas syringae bacteria.

Keywords: plant microbiome, nanoparticles, 16S rRNA gene sequencing, bacterial survival

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307 Effect of Depth on Texture Features of Ultrasound Images

Authors: M. A. Alqahtani, D. P. Coleman, N. D. Pugh, L. D. M. Nokes

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In diagnostic ultrasound, the echo graphic B-scan texture is an important area of investigation since it can be analyzed to characterize the histological state of internal tissues. An important factor requiring consideration when evaluating ultrasonic tissue texture is the depth. The effect of attenuation with depth of ultrasound, the size of the region of interest, gain, and dynamic range are important variables to consider as they can influence the analysis of texture features. These sources of variability have to be considered carefully when evaluating image texture as different settings might influence the resultant image. The aim of this study is to investigate the effect of depth on the texture features in-vivo using a 3D ultrasound probe. The left leg medial head of the gastrocnemius muscle of 10 healthy subjects were scanned. Two regions A and B were defined at different depth within the gastrocnemius muscle boundary. The size of both ROI’s was 280*20 pixels and the distance between region A and B was kept constant at 5 mm. Texture parameters include gray level, variance, skewness, kurtosis, co-occurrence matrix; run length matrix, gradient, autoregressive (AR) model and wavelet transform were extracted from the images. The paired t –test was used to test the depth effect for the normally distributed data and the Wilcoxon–Mann-Whitney test was used for the non-normally distributed data. The gray level, variance, and run length matrix were significantly lowered when the depth increased. The other texture parameters showed similar values at different depth. All the texture parameters showed no significant difference between depths A and B (p > 0.05) except for gray level, variance and run length matrix (p < 0.05). This indicates that gray level, variance, and run length matrix are depth dependent.

Keywords: ultrasound image, texture parameters, computational biology, biomedical engineering

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306 Hypervirulent Klebsiella Pneumoniae in a South African Tertiary Hospital – Clinical Profile, Genetic Determinants and Virulence in Caenorhabditis Elegans

Authors: Dingiswayo Likhona, Arko-Cobbah Emmanuel, Carolina Pohl, Nthabiseng Z. Mokoena, Jolly Musoke

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A distinct strain of Klebsiella pneumoniae (K. pneumoniae), referred to as hypervirulent (hvKp), is associated with invasive infections such as an invasive pyogenic liver abscess in young and healthy individuals. In South Africa, limited information is known about the prevalence and virulence of this hvKp strain. Thus, this study aimed to determine the prevalence of hvKp and virulence-associated factors in K. pneumoniae isolates from one of the largest Tertiary hospitals in a South African province. A total of 74 K. pneumoniae isolates were received from Pelonomi National Health Laboratory Services (NHLS), Bloemfontein. Virulence-associated genes (rmpA, capsule serotype K1/K2, iroB, and irp2) were screened, and the virulence of hvKp vs. classical Klebsiella pneumoniae (cKp) was investigated using Caenorhabditis elegans nematode model. The iutA (aerobactin transporter) gene was used as a primary biomarker of hvKp. An average of 12% (9/74) of cases were defined as hvKp. Moreover, hvKp was found to be significantly more virulent in vivo Caenorhabditis elegans relative to cKp. The virulence-associated genes (rmpA, iroB, hmv phenotype, and capsule K1/K2) were significantly (p< 0.05) associated with hvKp. Findings from this study confirm the presence of hvKp in one large Tertiary hospital in South Africa. However, the low prevalence and mild to moderate clinical presentation suggest a marginal threat to public health. Further studies in different settings are required to establish the true potential impact of hvKp in developing countries.

Keywords: hypervirulent klebsiella pneumoniae, virulence, caenorhabditis elegans, aerobactin (iutA)

Procedia PDF Downloads 51