Search results for: tissue specific genes
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 9404

Search results for: tissue specific genes

8984 Investigating the Essentiality of Oxazolidinones in Resistance-Proof Drug Combinations in Mycobacterium tuberculosis Selected under in vitro Conditions

Authors: Gail Louw, Helena Boshoff, Taeksun Song, Clifton Barry

Abstract:

Drug resistance in Mycobacterium tuberculosis is primarily attributed to mutations in target genes. These mutations incur a fitness cost and result in bacterial generations that are less fit, which subsequently acquire compensatory mutations to restore fitness. We hypothesize that mutations in specific drug target genes influence bacterial metabolism and cellular function, which affects its ability to develop subsequent resistance to additional agents. We aim to determine whether the sequential acquisition of drug resistance and specific mutations in a well-defined clinical M. tuberculosis strain promotes or limits the development of additional resistance. In vitro mutants resistant to pretomanid, linezolid, moxifloxacin, rifampicin and kanamycin were generated from a pan-susceptible clinical strain from the Beijing lineage. The resistant phenotypes to the anti-TB agents were confirmed by the broth microdilution assay and genetic mutations were identified by targeted gene sequencing. Growth of mono-resistant mutants was done in enriched medium for 14 days to assess in vitro fitness. Double resistant mutants were generated against anti-TB drug combinations at concentrations 5x and 10x the minimum inhibitory concentration. Subsequently, mutation frequencies for these anti-TB drugs in the different mono-resistant backgrounds were determined. The initial level of resistance and the mutation frequencies observed for the mono-resistant mutants were comparable to those previously reported. Targeted gene sequencing revealed the presence of known and clinically relevant mutations in the mutants resistant to linezolid, rifampicin, kanamycin and moxifloxacin. Significant growth defects were observed for mutants grown under in vitro conditions compared to the sensitive progenitor. Mutation frequencies determination in the mono-resistant mutants revealed a significant increase in mutation frequency against rifampicin and kanamycin, but a significant decrease in mutation frequency against linezolid and sutezolid. This suggests that these mono-resistant mutants are more prone to develop resistance to rifampicin and kanamycin, but less prone to develop resistance against linezolid and sutezolid. Even though kanamycin and linezolid both inhibit protein synthesis, these compounds target different subunits of the ribosome, thereby leading to different outcomes in terms of fitness in the mutants with impaired cellular function. These observations showed that oxazolidinone treatment is instrumental in limiting the development of multi-drug resistance in M. tuberculosis in vitro.

Keywords: oxazolidinones, mutations, resistance, tuberculosis

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8983 Use of Amaranthus Roxburghianus Root Extract in the Treatment of Ulcerative Colitis in Mice

Authors: S. A. Nirmal, J. M. Ingale, G. S. Asane, S. C. Pal, Subhash C. Mandal

Abstract:

The present work was undertaken to determine the effects of Amaranthus roxburghianus Nevski. (Amaranthaceae) root alone and in combination with piperine in treating ulcerative colitis (UC) in mice. Swiss albino mice were divided into seven groups (n = 6). Standard group received prednisolone (5 mg/kg, i.p.). Treatment groups received hydroalcoholic extract of roots of A. roxburghianus (50 and 100 mg/kg, p.o.) and a combination of hydroalcoholic extract of roots of A. roxburghianus (50 and 100 mg/kg, p.o.) and piperine (5 mg/kg, p.o.). Ulcer index, colitis severity, myeloperoxidase (MPO), malondialdehyde and glutathione were estimated from blood and tissue. Column chromatography of the extract was done and purified fractions were analyzed by gas chromatography-mass spectroscopy (GC-MS). Treatment with the combination of hydroalcoholic extract of A. roxburghianus and piperine showed minimal ulceration, hemorrhage, necrosis and leucocyte infiltration by histopathological observation. Acetic acid increased MPO levels in blood and colon tissue to 355 U/mL and 385 U/mg, respectively. The combination of hydroalcoholic extract (100 mg/kg) and piperine (5 mg/kg) significantly decreased MPO in blood and tissue to 182 U/mL and 193 U/mg, respectively. Similarly, this combination significantly reduced MPO and increased glutathione levels in blood and tissue. Various phytoconstituents were detected by GC-MS. The combination of hydroalcoholic extract and piperine is effective in the treatment of UC and the effects are comparable with the standard drug prednisolone. 4H-pyran-4-one, 2,3-dihydro-3,5-dihydroxy-6-methyl, eugenol and benzene, and 1-(1,5-dimethyl-4-hexenyl)-4-methyl are reported having analgesic, anti-inflammatory, and antioxidant properties; they may play a role in the biological activity of A. roxburghianus root.

Keywords: Amaranthus roxburghianus, ulcerative colitis, anti-inflammatory, ulcerative colitis

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8982 Characterization of Defense-Related Genes and Metabolite Profiling in Oil Palm Elaeis guineensis during Interaction with Ganoderma boninense

Authors: Mohammad Nazri Abdul Bahari, Nurshafika Mohd Sakeh, Siti Nor Akmar Abdullah

Abstract:

Basal stem rot (BSR) is the most devastating disease in oil palm. Among the oil palm pathogenic fungi, the most prevalent and virulent species associated with BSR is Ganoderma boninense. Early detection of G. boninense attack in oil palm wherein physical symptoms has not yet appeared can offer opportunities to prevent the spread of the necrotrophic fungus. However, poor understanding of molecular defense responses and roles of antifungal metabolites in oil palm against G. boninense has complicated the resolving measures. Hence, characterization of defense-related molecular responses and production of antifungal compounds during early interaction with G. boninense is of utmost important. Four month-old oil palm (Elaeis guineensis) seedlings were artificially infected with G. boninense-inoculated rubber wood block via sitting technique. RNA of samples were extracted from roots and leaves tissues at 0, 3, 7 and 11 days post inoculation (d.p.i) followed with sequencing using RNA-Seq method. Differentially-expressed genes (DEGs) of oil palm-G. boninense interaction were identified, while changes in metabolite profile will be scrutinized related to the DEGs. The RNA-Seq data generated a total of 113,829,376 and 313,293,229 paired-end clean reads from untreated (0 d.p.i) and treated (3, 7, 11 d.p.i) samples respectively, each with two biological replicates. The paired-end reads were mapped to Elaeis guineensis reference genome to screen out non-oil palm genes and subsequently generated 74,794 coding sequences. DEG analysis of phytohormone biosynthetic genes in oil palm roots revealed that at p-value ≤ 0.01, ethylene and jasmonic acid may act in antagonistic manner with salicylic acid to coordinate defense response at early interaction with G. boninense. Findings on metabolite profiling of G. boninense-infected oil palm roots and leaves are hoped to explain the defense-related compounds elicited by Elaeis guineensis in response to G. boninense colonization. The study aims to shed light on molecular defense response of oil palm at early interaction with G. boninense and promote prevention measures against Ganoderma infection.

Keywords: Ganoderma boninense, metabolites, phytohormones, RNA-Seq

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8981 Design of Nanoreinforced Polyacrylamide-Based Hybrid Hydrogels for Bone Tissue Engineering

Authors: Anuj Kumar, Kummara M. Rao, Sung S. Han

Abstract:

Bone tissue engineering has emerged as a potentially alternative method for localized bone defects or diseases, congenital deformation, and surgical reconstruction. The designing and the fabrication of the ideal scaffold is a great challenge, in restoring of the damaged bone tissues via cell attachment, proliferation, and differentiation under three-dimensional (3D) biological micro-/nano-environment. In this case, hydrogel system composed of high hydrophilic 3D polymeric-network that is able to mimic some of the functional physical and chemical properties of the extracellular matrix (ECM) and possibly may provide a suitable 3D micro-/nano-environment (i.e., resemblance of native bone tissues). Thus, this proposed hydrogel system is highly permeable and facilitates the transport of the nutrients and metabolites. However, the use of hydrogels in bone tissue engineering is limited because of their low mechanical properties (toughness and stiffness) that continue to posing challenges in designing and fabrication of tough and stiff hydrogels along with improved bioactive properties. For this purpose, in our lab, polyacrylamide-based hybrid hydrogels were synthesized by involving sodium alginate, cellulose nanocrystals and silica-based glass using one-step free-radical polymerization. The results showed good in vitro apatite-forming ability (biomineralization) and improved mechanical properties (under compression in the form of strength and stiffness in both wet and dry conditions), and in vitro osteoblastic (MC3T3-E1 cells) cytocompatibility. For in vitro cytocompatibility assessment, both qualitative (attachment and spreading of cells using FESEM) and quantitative (cell viability and proliferation using MTT assay) analyses were performed. The obtained hybrid hydrogels may potentially be used in bone tissue engineering applications after establishment of in vivo characterization.

Keywords: bone tissue engineering, cellulose nanocrystals, hydrogels, polyacrylamide, sodium alginate

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8980 Exploring Simple Sequence Repeats within Conserved microRNA Precursors Identified from Tea Expressed Sequence Tag (EST) Database

Authors: Anjan Hazra, Nirjhar Dasgupta, Chandan Sengupta, Sauren Das

Abstract:

Tea (Camellia sinensis) has received substantial attention from the scientific world time to time, not only for its commercial importance, but also for its demand to the health-conscious people across the world for its extensive use as potential sources of antioxidant supplement. These health-benefit traits primarily rely on some regulatory networks of different metabolic pathways. Development of microsatellite markers from the conserved genomic regions is being worthwhile for studying the genetic diversity of closely related species or self-pollinated species. Although several SSR markers have been reported, in tea the trait-specific Simple Sequence Repeats (SSRs) are yet to be identified, which can be used for marker assisted breeding technique. MicroRNAs are endogenous, noncoding, short RNAs directly involved in regulating gene expressions at the post-transcriptional level. It has been found that diversity in miRNA gene interferes the formation of its characteristic hair pin structure and the subsequent function. In the present study, the precursors of small regulatory RNAs (microRNAs) has been fished out from tea Expressed Sequence Tag (EST) database. Furthermore, the simple sequence repeat motifs within the putative miRNA precursor genes are also identified in order to experimentally validate their existence and function. It is already known that genic-SSR markers are very adept and breeder-friendly source for genetic diversity analysis. So, the potential outcome of this in-silico study would provide some novel clues in understanding the miRNA-triggered polymorphic genic expression controlling specific metabolic pathways, accountable for tea quality.

Keywords: micro RNA, simple sequence repeats, tea quality, trait specific marker

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8979 Magnetohemodynamic of Blood Flow Having Impact of Radiative Flux Due to Infrared Magnetic Hyperthermia: Spectral Relaxation Approach

Authors: Ebenezer O. Ige, Funmilayo H. Oyelami, Joshua Olutayo-Irheren, Joseph T. Okunlola

Abstract:

Hyperthermia therapy is an adjuvant procedure during which perfused body tissues is subjected to elevated range of temperature in bid to achieve improved drug potency and efficacy of cancer treatment. While a selected class of hyperthermia techniques is shouldered on the thermal radiations derived from single-sourced electro-radiation measures, there are deliberations on conjugating dual radiation field sources in an attempt to improve the delivery of therapy procedure. This paper numerically explores the thermal effectiveness of combined infrared hyperemia having nanoparticle recirculation in the vicinity of imposed magnetic field on subcutaneous strata of a model lesion as ablation scheme. An elaborate Spectral relaxation method (SRM) was formulated to handle equation of coupled momentum and thermal equilibrium in the blood-perfused tissue domain of a spongy fibrous tissue. Thermal diffusion regimes in the presence of external magnetic field imposition were described leveraging on the renowned Roseland diffusion approximation to delineate the impact of radiative flux within the computational domain. The contribution of tissue sponginess was examined using mechanics of pore-scale porosity over a selected of clinical informed scenarios. Our observations showed for a substantial depth of spongy lesion, magnetic field architecture constitute the control regimes of hemodynamics in the blood-tissue interface while facilitating thermal transport across the depth of the model lesion. This parameter-indicator could be utilized to control the dispensing of hyperthermia treatment in intravenous perfused tissue.

Keywords: spectra relaxation scheme, thermal equilibrium, Roseland diffusion approximation, hyperthermia therapy

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8978 Literature Review of the Management of Parry Romberg Syndrome with Fillers

Authors: Sana Ilyas

Abstract:

Parry-Romberg syndrome is a rare condition clinically defined by slowly progressive atrophy of the skin and soft tissues. This usually effects one side of the face, although a few cases have been documented of bilateral presentation. It is more prevalent in females and usually affects the left side of the face. The syndrome can also be accompanied by neurological abnormalities. It usually occurs in the first two decades of life with a variable rate of progression. The aetiology is unknown, and the disease eventually stabilises. The treatment options usually involve surgical management. The least invasive of these options is the management of facial asymmetry, associated with Parry Romberg syndrome, through the use of tissue fillers. This paper will review the existing literature on the management of Parry Romberg syndrome with tissue filler. Aim: The aim of the study is to explore the current published literature for the management of Parry Romberg syndrome with fillers. It is to assess the development that has been made in this method of management, its benefits and limitations, and its effectiveness for the management of Parry Romberg syndrome. Methodology: There was a thorough assessment of the current literature published on this topic. PubMed database was used for search of the published literature on this method of the management. Papers were analysed and compared with one another to assess the success and limitation of the management of Parry Romberg with dermal fillers Results and Conclusion: Case reports of the use of tissue fillers discuss the varying degrees of success with the treatment. However, this procedure has it’s limitation, which are discussed in the paper in detail. However, it is still the least invasive of all the surgical options for the management of Parry Romberg Syndrome, and therefore, it is important to explore this option with patients, as they may be more comfortable with pursuingtreatment that is less invasive and can still improve their facial asymmetry

Keywords: dermal fillers, facial asymmetry, parry romberg syndrome, tissue fillers

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8977 Primer Design for the Detection of Secondary Metabolite Biosynthetic Pathways in Metagenomic Data

Authors: Jeisson Alejandro Triana, Maria Fernanda Quiceno Vallejo, Patricia del Portillo, Juan Manuel Anzola

Abstract:

Most of the known antimicrobials so far discovered are secondary metabolites. The potential for new natural products of this category increases as new microbial genomes and metagenomes are being sequenced. Despite the advances, there is no systematic way to interrogate metagenomic clones for their potential to contain clusters of genes related to these pathways. Here we analyzed 52 biosynthetic pathways from the AntiSMASH database at the protein domain level in order to identify domains of high specificity and sensitivity with respect to specific biosynthetic pathways. These domains turned out to have various degrees of divergence at the DNA level. We propose PCR assays targetting such domains in-silico and corroborated one by Sanger sequencing.

Keywords: bioinformatic, anti smash, antibiotics, secondary metabolites, natural products, protein domains

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8976 Prospects of Acellular Organ Scaffolds for Drug Discovery

Authors: Inna Kornienko, Svetlana Guryeva, Natalia Danilova, Elena Petersen

Abstract:

Drug toxicity often goes undetected until clinical trials, the most expensive and dangerous phase of drug development. Both human cell culture and animal studies have limitations that cannot be overcome by improvements in drug testing protocols. Tissue engineering is an emerging alternative approach to creating models of human malignant tumors for experimental oncology, personalized medicine, and drug discovery studies. This new generation of bioengineered tumors provides an opportunity to control and explore the role of every component of the model system including cell populations, supportive scaffolds, and signaling molecules. An area that could greatly benefit from these models is cancer research. Recent advances in tissue engineering demonstrated that decellularized tissue is an excellent scaffold for tissue engineering. Decellularization of donor organs such as heart, liver, and lung can provide an acellular, naturally occurring three-dimensional biologic scaffold material that can then be seeded with selected cell populations. Preliminary studies in animal models have provided encouraging results for the proof of concept. Decellularized Organs preserve organ microenvironment, which is critical for cancer metastasis. Utilizing 3D tumor models results greater proximity of cell culture morphological characteristics in a model to its in vivo counterpart, allows more accurate simulation of the processes within a functioning tumor and its pathogenesis. 3D models allow study of migration processes and cell proliferation with higher reliability as well. Moreover, cancer cells in a 3D model bear closer resemblance to living conditions in terms of gene expression, cell surface receptor expression, and signaling. 2D cell monolayers do not provide the geometrical and mechanical cues of tissues in vivo and are, therefore, not suitable to accurately predict the responses of living organisms. 3D models can provide several levels of complexity from simple monocultures of cancer cell lines in liquid environment comprised of oxygen and nutrient gradients and cell-cell interaction to more advanced models, which include co-culturing with other cell types, such as endothelial and immune cells. Following this reasoning, spheroids cultivated from one or multiple patient-derived cell lines can be utilized to seed the matrix rather than monolayer cells. This approach furthers the progress towards personalized medicine. As an initial step to create a new ex vivo tissue engineered model of a cancer tumor, optimized protocols have been designed to obtain organ-specific acellular matrices and evaluate their potential as tissue engineered scaffolds for cultures of normal and tumor cells. Decellularized biomatrix was prepared from animals’ kidneys, urethra, lungs, heart, and liver by two decellularization methods: perfusion in a bioreactor system and immersion-agitation on an orbital shaker with the use of various detergents (SDS, Triton X-100) in different concentrations and freezing. Acellular scaffolds and tissue engineered constructs have been characterized and compared using morphological methods. Models using decellularized matrix have certain advantages, such as maintaining native extracellular matrix properties and biomimetic microenvironment for cancer cells; compatibility with multiple cell types for cell culture and drug screening; utilization to culture patient-derived cells in vitro to evaluate different anticancer therapeutics for developing personalized medicines.

Keywords: 3D models, decellularization, drug discovery, drug toxicity, scaffolds, spheroids, tissue engineering

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8975 Investigation on Single Nucleotide Polymorphism in Candidate Genes and Their Association with Occurrence of Mycobacterium avium Subspecies Paratuberculosis Infection in Cattle

Authors: Ran Vir Singh, Anuj Chauhan, Subhodh Kumar, Rajesh Rathore, Satish Kumar, B Gopi, Sushil Kumar, Tarun Kumar, Ramji Yadav, Donna Phangchopi, Shoor Vir Singh

Abstract:

Paratuberculosis caused by Mycobacterium avium subspecies paratuberculosis (MAP) is a chronic granulomatous enteritis affecting ruminants. It is responsible for significant economic losses in livestock industry worldwide. This organism is also of public health concern due to an unconfirmed link to Crohn’s disease. Susceptibility to paratuberculosis has been suggested to have genetic component with low to moderate heritability. Number of SNPs in various candidates genes have been observed to be affecting the susceptibility toward paratuberculosis. The objective of this study was to explore the association of various SNPs in the candidate genes and QTL region with MAP. A total of 117 SNPs from SLC11A1, IFNG, CARD15, TLR2, TLR4, CLEC7A, CD209, SP110, ANKARA2, PGLYRP1 and one QTL were selected for study. A total of 1222 cattle from various organized herds, gauhsalas and farmer herds were screened for MAP infection by Johnin intradermal skin test, AGID, serum ELISA, fecal microscopy, fecal culture and IS900 blood PCR. Based on the results of these tests, a case and control population of 200 and 183 respectively was established for study. A total of 117 SNPs from 10 candidate genes and one QTL were selected and validated/tested in our case and control population by PCR-RFLP technique. Data was analyzed using SAS 9.3 software. Statistical analysis revealed that, 107 out of 117 SNPs were not significantly associated with occurrence of MAP. Only SNP rs55617172 of TLR2, rs8193046 and rs8193060 of TLR4, rs110353594 and rs41654445 of CLEC7A, rs208814257of CD209, rs41933863 of ANKRA2, two loci {SLC11A1(53C/G)} and {IFNG (185 G/r) } and SNP rs41945014 in QTL region was significantly associated with MAP. Six SNP from 10 significant SNPs viz., rs110353594 and rs41654445 from CLEC7A, rs8193046 and rs8193060 from TLR4, rs109453173 from SLC11A1 rs208814257 from CD209 were validated in new case and control population. Out of these only one SNP rs8193046 of TLR4 gene was found significantly associated with occurrence of MAP in cattle. ODD ratio indicates that animals with AG genotype were more susceptible to MAP and this finding is in accordance with the earlier report. Hence it reaffirms that AG genotype can serve as a reliable genetic marker for indentifying more susceptible cattle in future selection against MAP infection in cattle.

Keywords: SNP, candidate genes, paratuberculosis, cattle

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8974 Molecular Detection and Antibiotics Resistance Pattern of Extended-Spectrum Beta-Lactamase Producing Escherichia coli in a Tertiary Hospital in Enugu, Nigeria

Authors: I. N. Nwafia, U. C. Ozumba, M. E. Ohanu, S. O. Ebede

Abstract:

Antibiotic resistance is increasing globally and has become a major health challenge. Extended-spectrum beta-lactamase is clinically important because the ESBL gene are mostly plasmid encoded and these plasmids frequently carry genes encoding resistance to other classes of antimicrobials thereby limiting antibiotic options in the treatment of infections caused by these organisms. The specific objectives of this study were to determine the prevalence of ESBLs production in Escherichia coli, to determine the antibiotic susceptibility pattern of ESBLs producing Escherichia coli, to detect TEM, SHV and CTX-M genes and the risk factors to acquisition of ESBL producing Escherichia coli. The protocol of the study was approved by Health Research and Ethics committee of the University of Nigeria Teaching Hospital (UNTH), Enugu. It was a descriptive cross-sectional study that involved all hospitalized patients in UNTH from whose specimens Escherichia coli was isolated during the period of the study. The samples analysed were urine, wound swabs, blood and cerebrospinal fluid. These samples were cultured in 5% sheep Blood agar and MacConkey agar (Oxoid Laboratories, Cambridge UK) and incubated at 35-370C for 24 hours. Escherichia coli was identified with standard biochemical tests and confirmed using API 20E auxanogram (bioMerieux, Marcy 1'Etoile, France). The antibiotic susceptibility testing was done by disc diffusion method and interpreted according to the Clinical and Laboratory Standard Institute guideline. ESBL production was confirmed using ESBL Epsilometer test strips (Liofilchem srl, Italy). The ESBL bla genes were detected with polymerase chain reaction, after extraction of DNA with plasmid mini-prep kit (Jena Bioscience, Jena, Germany). Data analysis was with appropriate descriptive and inferential statistics. One hundred and six isolates (53.00%) out of the 200 were from urine, followed by isolates from different swabs specimens 53(26.50%) and the least number of the isolates 4(2.00) were from blood (P value = 0.096). Seventy (35.00%) out of the 200 isolates, were confirmed positive for ESBL production. Forty-two (60.00%) of the isolates were from female patients while 28(40.00%) were from male patients (P value = 0.13). Sixty-eight (97.14%) of the isolates were susceptible to imipenem while all of the isolates were resistant to ampicillin, chloramphenicol and tetracycline. From the 70 positive isolates the ESBL genes detected with polymerase chain reaction were blaCTX-M (n=26; 37.14%), blaTEM (n=7; 10.00%), blaSHV (n=2; 2.86%), blaCTX-M/TEM (n=7; 10.0%), blaCTX-M/SHV (n=14; 20.0%) and blaCTX-M/TEM/SHV (n=10; 14.29%). There was no gene detected in 4(5.71%) of the isolates. The most associated risk factors to infections caused by ESBL producing Escherichia coli was previous antibiotics use for the past 3 months followed by admission in the intensive care unit, recent surgery, and urinary catheterization. In conclusion, ESBLs was detected in 4 of every 10 Escherichia coli with the predominant gene detected being CTX-M. This knowledge will enable appropriate measures towards improvement of patient health care, antibiotic stewardship, research and infection control in the hospital.

Keywords: antimicrobial, Escherichia coli, extended spectrum beta lactamase, resistance

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8973 Olive Oil (Olea europea L.) Protects against Mercury (II) Induced Oxidative Tissue Damage in Rats

Authors: Ahlem Bahi, Youcef Necib, Sakina Zerizer, Cherif Abdennour, Mohamed Salah Boulakoud

Abstract:

Mercury (II) is a highly toxic metal which induces oxidative stress in the body. In this study, we aimed to investigate the possible protective effect of olive oil, an antioxidant agent, against experimental mercury toxicity in rat model. Administration of mercuric chloride induced significant increase in serum: ALT, AST, and LPA activities; interleukine1, interleukine6, tumor necrosis factor α (TNFα), creatinine, urea, and uric acid levels. Mercuric chloride also induced oxidative stress, as indicate by decreased tissue of GSH level, GSH-Px, and GST activities along with increase the level of lipid peroxidation. Furthermore, treatment with mercuric chloride caused a marked elevation of kidney and liver weight and decreased body weight. Virgin olive oil treatment markedly reduced elevated serum: AST, ALT, and LPA activities; interleukine1, interleukine6, tumor necrosis factor α (TNFα), creatinine, urea, and uric acid levels and contracted the deterious effects of mercuric chloride on oxidative stress markers changes caused by HgCl2 in tissue as compared to control group. Our results implicate that mercury induced oxidative damage in liver and kidney tissue protected by virgin olive oil, with its antioxidant effects.

Keywords: mercury, antioxidant enzymes, pro-inflammatory cytokine, virgin olive oil, lipid peroxidation

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8972 Dry Modifications of PCL/Chitosan/PCL Tissue Scaffolds

Authors: Ozan Ozkan, Hilal Turkoglu Sasmazel

Abstract:

Natural polymers are widely used in tissue engineering applications, because of their biocompatibility, biodegradability and solubility in the physiological medium. On the other hand, synthetic polymers are also widely utilized in tissue engineering applications, because they carry no risk of infectious diseases and do not cause immune system reaction. However, the disadvantages of both polymer types block their individual usages as tissue scaffolds efficiently. Therefore, the idea of usage of natural and synthetic polymers together as a single 3D hybrid scaffold which has the advantages of both and the disadvantages of none has been entered to the literature. On the other hand, even though these hybrid structures support the cell adhesion and/or proliferation, various surface modification techniques applied to the surfaces of them to create topographical changes on the surfaces and to obtain reactive functional groups required for the immobilization of biomolecules, especially on the surfaces of synthetic polymers in order to improve cell adhesion and proliferation. In a study presented here, to improve the surface functionality and topography of the layer by layer electrospun 3D poly-epsilon-caprolactone/chitosan/poly-epsilon-caprolactone hybrid tissue scaffolds by using atmospheric pressure plasma method, thus to improve cell adhesion and proliferation of these tissue scaffolds were aimed. The formation/creation of the functional hydroxyl and amine groups and topographical changes on the surfaces of scaffolds were realized by using two different atmospheric pressure plasma systems (nozzle type and dielectric barrier discharge (DBD) type) carried out under different gas medium (air, Ar+O2, Ar+N2). The plasma modification time and distance for the nozzle type plasma system as well as the plasma modification time and the gas flow rate for DBD type plasma system were optimized with monitoring the changes in surface hydrophilicity by using contact angle measurements. The topographical and chemical characterizations of these modified biomaterials’ surfaces were carried out with SEM and ESCA, respectively. The results showed that the atmospheric pressure plasma modifications carried out with both nozzle type plasma and DBD plasma caused topographical and functionality changes on the surfaces of the layer by layer electrospun tissue scaffolds. However, the shelf life studies indicated that the hydrophilicity introduced to the surfaces was mainly because of the functionality changes. Therefore, according to the optimized results, samples treated with nozzle type air plasma modification applied for 9 minutes from a distance of 17 cm and Ar+O2 DBD plasma modification applied for 1 minute under 70 cm3/min O2 flow rate were found to have the highest hydrophilicity compared to pristine samples.

Keywords: biomaterial, chitosan, hybrid, plasma

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8971 Upconversion Nanomaterials for Applications in Life Sciences and Medicine

Authors: Yong Zhang

Abstract:

Light has proven to be useful in a wide range of biomedical applications such as fluorescence imaging, photoacoustic imaging, optogenetics, photodynamic therapy, photothermal therapy, and light controlled drug/gene delivery. Taking photodynamic therapy (PDT) as an example, PDT has been proven clinically effective in early lung cancer, bladder cancer, head, and neck cancer and is the primary treatment for skin cancer as well. However, clinical use of PDT is severely constrained by the low penetration depth of visible light through thick tissue, limiting its use to target regions only a few millimeters deep. One way to enhance the range is to use invisible near-infrared (NIR) light within the optical window (700–1100nm) for biological tissues, extending the depth up to 1cm with no observable damage to the intervening tissue. We have demonstrated use of NIR-to-visible upconversion fluorescent nanoparticles (UCNPs), emitting visible fluorescence when excited by a NIR light at 980nm, as a nanotransducer for PDT to convert deep tissue-penetrating NIR light to visible light suitable for activating photosensitizers. The unique optical properties of UCNPs enable the upconversion wavelength to be tuned and matched to the activation absorption wavelength of the photosensitizer. At depths beyond 1cm, however, tissue remains inaccessible to light even within the NIR window, and this critical depth limitation renders existing phototherapy ineffective against most deep-seated cancers. We have demonstrated some new treatment modalities for deep-seated cancers based on UCNP hydrogel implants and miniaturized, wirelessly powered optoelectronic devices for light delivery to deep tissues.

Keywords: upconversion, fluorescent, nanoparticle, bioimaging, photodynamic therapy

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8970 Additive Manufacturing of Titanium Metamaterials for Tissue Engineering

Authors: Tuba Kizilirmak

Abstract:

Distinct properties of porous metamaterials have been largely processed for biomedicine requiring a three-dimensional (3D) porous structure engaged with fine mechanical features, biodegradation ability, and biocompatibility. Applications of metamaterials are (i) porous orthopedic and dental implants; (ii) in vitro cell culture of metamaterials and bone regeneration of metamaterials in vivo; (iii) macro-, micro, and nano-level porous metamaterials for sensors, diagnosis, and drug delivery. There are some specific properties to design metamaterials for tissue engineering. These are surface to volume ratio, pore size, and interconnection degrees are selected to control cell behavior and bone ingrowth. In this study, additive manufacturing technique selective laser melting will be used to print the scaffolds. Selective Laser Melting prints the 3D components according to designed 3D CAD models and manufactured materials, adding layers progressively by layer. This study aims to design metamaterials with Ti6Al4V material, which gives benefit in respect of mechanical and biological properties. Ti6Al4V scaffolds will support cell attachment by conferring a suitable area for cell adhesion. This study will control the osteoblast cell attachment on Ti6Al4V scaffolds after the determination of optimum stiffness and other mechanical properties which are close to mechanical properties of bone. Before we produce the samples, we will use a modeling technique to simulate the mechanical behavior of samples. These samples include different lattice models with varying amounts of porosity and density.

Keywords: additive manufacturing, titanium lattices, metamaterials, porous metals

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8969 Biodegradation Ability of Polycyclic Aromatic Hydrocarbon (PAHs) Degrading Bacillus cereus Strain JMG-01 Isolated from PAHs Contaminated Soil

Authors: Momita Das, Sofia Banu, Jibon Kotoky

Abstract:

Environmental contamination of natural resources with persistent organic pollutants is of great world-wide apprehension. Polycyclic aromatic hydrocarbons (PAHs) are among the organic pollutants, released due to various anthropogenic activities. Due to their toxic, carcinogenic and mutagenic properties, PAHs are of environmental and human concern. Presently, bioremediation has evolved as the most promising biotechnology for cleanup of such contaminants because of its economical and less cost effectiveness. In the present study, distribution of 16 USEPA priority PAHs was determined in the soil samples collected from fifteen different sites of Guwahati City, the Gateway of the North East Region of India. The total concentrations of 16 PAHs (Σ16 PAHs) ranged from 42.7-742.3 µg/g. Higher concentration of total PAHs was found more in the Industrial areas compared to all the sites (742.3 µg/g and 628 µg/g). It is noted that among all the PAHs, Naphthalene, Acenaphthylene, Anthracene, Fluoranthene, Chrysene and Benzo(a)Pyrene were the most available and contain the higher concentration of all the PAHs. Since microbial activity has been deemed the most influential and significant cause of PAH removal; further, twenty-three bacteria were isolated from the most contaminated sites using the enrichment process. These strains were acclimatized to utilize naphthalene and anthracene, each at 100 µg/g concentration as sole carbon source. Among them, one Gram-positive strain (JMG-01) was selected, and biodegradation ability and initial catabolic genes of PAHs degradation were investigated. Based on 16S rDNA analysis, the isolate was identified as Bacillus cereus strain JMG-01. Topographic images obtained using Scanning Electron Microscope (SEM) and Atomic Force Microscope (AFM) at scheduled time intervals of 7, 14 and 21 days, determined the variation in cell morphology during the period of degradation. AFM and SEM micrograph of biomass showed high filamentous growth leading to aggregation of cells in the form of biofilm with reference to the incubation period. The percentage degradation analysis using gas chromatography and mass analyses (GC-MS) suggested that more than 95% of the PAHs degraded when the concentration was at 500 µg/g. Naphthalene, naphthalene-2-methy, benzaldehyde-4-propyl, 1, 2, benzene di-carboxylic acid and benzene acetic acid were the major metabolites produced after degradation. Moreover, PCR experiments with specific primers for catabolic genes, ndo B and Cat A suggested that JMG-01 possess genes for PAHs degradation. Thus, the study concludes that Bacillus cereus strain JMG-01 has efficient biodegrading ability and can trigger the clean-up of PAHs contaminated soil.

Keywords: AFM, Bacillus cereus strain JMG-01, degradation, polycyclic aromatic hydrocarbon, SEM

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8968 Deciphering Electrochemical and Optical Properties of Folic Acid for the Applications of Tissue Engineering and Biofuel Cell

Authors: Sharda Nara, Bansi Dhar Malhotra

Abstract:

Investigation of the vitamins as an electron transfer mediator could significantly assist in merging the area of tissue engineering and electronics required for the implantable therapeutic devices. The present study report that the molecules of folic acid released by Providencia rettgeri via fermentation route under the anoxic condition of the microbial fuel cell (MFC) exhibit characteristic electrochemical and optical properties, as indicated by absorption spectroscopy, photoluminescence (PL), and cyclic voltammetry studies. The absorption spectroscopy has depicted an absorption peak at 263 nm with a small bulge around 293 nm on day two of bacterial culture, whereas an additional peak was observed at 365 nm on the twentieth day. Furthermore, the PL spectra has indicated that the maximum emission occurred at various wavelengths 420, 425, 440, and 445 nm when excited by 310, 325, 350, and 365 nm. The change of emission spectra with varying excitation wavelength might be indicating the presence of tunable optical bands in the folic acid molecules co-related with the redox activity of the molecules. The results of cyclic voltammetry studies revealed that the oxidation and reduction occurred at 0.25V and 0.12V, respectively, indicating the electrochemical behavior of the folic acid. This could be inferred that the released folic acid molecules in a MFC might undergo inter as well as intra molecular electron transfer forming different intermediate states while transferring electrons to the electrode surface. Synchronization of electrochemical and optical properties of folic acid molecules could be potentially promising for the designing of electroactive scaffold and biocompatible conductive surface for the applications of tissue engineering and biofuel cells, respectively.

Keywords: biofuel cell, electroactivity, folic acid, tissue engineering

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8967 Induced Bone Tissue Temperature in Drilling Procedures: A Comparative Laboratory Study with and without Lubrication

Authors: L. Roseiro, C. Veiga, V. Maranha, A. Neto, N. Laraqi, A. Baïri, N. Alilat

Abstract:

In orthopedic surgery there are various situations in which the surgeon needs to implement methods of cutting and drilling the bone. With this type of procedure the generated friction leads to a localized increase in temperature, which may lead to the bone necrosis. Recognizing the importance of studying this phenomenon, an experimental evaluation of the temperatures developed during the procedure of drilling bone has been done. Additionally the influence of the use of the procedure with / without additional lubrication during drilling of bone has also been done. The obtained results are presented and discussed and suggests an advantage in using additional lubrication as a way to minimize the appearance of bone tissue necrosis during bone drilling procedures.

Keywords: bone necrosis, bone drilling, thermography, surgery

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8966 3D Medical Printing the Key Component in Future of Medical Applications

Authors: Zahra Asgharpour, Eric Renteria, Sebastian De Boodt

Abstract:

There is a growing trend towards personalization of medical care, as evidenced by the emphasis on outcomes based medicine, the latest developments in CT and MR imaging and personalized treatment in a variety of surgical disciplines. 3D Printing has been introduced and applied in the medical field since 2000. The first applications were in the field of dental implants and custom prosthetics. According to recent publications, 3D printing in the medical field has been used in a wide range of applications which can be organized into several categories including implants, prosthetics, anatomical models and tissue bioprinting. Some of these categories are still in their infancy stage of the concept of proof while others are in application phase such as the design and manufacturing of customized implants and prosthesis. The approach of 3D printing in this category has been successfully used in the health care sector to make both standard and complex implants within a reasonable amount of time. In this study, some of the clinical applications of 3D printing in design and manufacturing of a patient-specific hip implant would be explained. In cases where patients have complex bone geometries or are undergoing a complex revision on hip replacement, the traditional surgical methods are not efficient, and hence these patients require patient-specific approaches. There are major advantages in using this new technology for medical applications, however, in order to get this technology widely accepted in medical device industry, there is a need for gaining more acceptance from the medical device regulatory offices. This is a challenge that is moving onward and will help the technology find its way at the end as an accepted manufacturing method for medical device industry in an international scale. The discussion will conclude with some examples describing the future directions of 3D Medical Printing.

Keywords: CT/MRI, image processing, 3D printing, medical devices, patient specific implants

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8965 Development and Utilization of Keratin-Fibrin-Gelatin Composite Films as Potential Material for Skin Tissue Engineering Application

Authors: Sivakumar Singaravelu, Giriprasath Ramanathan, M. D. Raja, Uma Tirichurapalli Sivagnanam

Abstract:

The goal of the present study was to develop and evaluate composite film for tissue engineering application. The keratin was extracted from bovine horn and used for preparation of keratin (HK), physiologically clotted fibrin (PCF) and gelatin (G) blend films in different stoichiometric ratios (1:1:1, 1:1:2 and 1:1:3) by using solvent casting method. The composite films (HK-PCF-G) were characterized physiochemically using Fourier Transform Infrared Spectroscopy (FTIR), Differential Scanning Calorimetry (DSC), Thermogravimetric Analysis (TGA) and Scanning Electron Microscopy (SEM). The mechanical properties of the composite films were analyzed. The results of tensile strength show that ultimate strength and elongation were 10.72 Mpa and 4.83 MPA respectively for 1:1:3 ratio combination. The SEM image showed a slight smooth surface for 1:1:3 ratio combination compared to other films. In order to impart antibacterial activities, the composite films were loaded with Mupirocin (MP) to act against infection. The composite films acted as a suitable carrier to protect and release the drug in a controlled manner. This developed composite film would be a suitable alternative material for tissue engineering application.

Keywords: bovine horn, keratin, fibrin, gelatin, tensile strength

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8964 The Impact of P108L Genetic Variant on Calcium Release and Malignant Hyperthermia Susceptibility

Authors: Mohammed Althobiti, Patrick Booms, Dorota Fiszer, Philip Hopkins

Abstract:

Malignant hyperthermia (MH) is a pharmacogenetic disorder of skeletal muscle. MH results from anaesthetics induced breakdown of calcium homeostasis. RYR1 and CACN1AS mutations represent the aetiology in ~70% of the MH population. Previous studies indicate that up to 25% of MH patients carry no variants in these genes. Therefore, the aim of this study is to investigate the relationships between MH susceptibility and genes encoding skeletal muscle Ca2+ channels as well as accessory proteins. The JSRP, encoding JP-45, was previously sequenced and novel genetic variants were identified. The variant p.P108L (c.323C > T) was identified in exon 4 and encodes a change from a proline at amino acid 108 to leucine residue. The variant P108L was detected in two patients out of 50 with 4% frequency in the sample population. The alignment of DNA sequences in different species indicates highly conserved proline sequences involved in the substitution of the P108L variant. In this study, the variant P108L co-segregates with the SNP p.V92A (c.275T > C) at the same exon, both variants being inherited in the same two patients only. This indicates that the two variants may represent a haplotype. Therefore, a set of single nucleotide polymorphisms and statistical analysis will be used to investigate the effects of haplotypes on MH susceptibility. Furthermore, investigating the effect of the P108L variant in combination with RYR1 mutations or other genetic variants in other genes as a combination of two or more genetic variants, haplotypes may then provide stronger genetic evidence indicating that JSRP1 is associated with MH susceptibility. In conclusion, these preliminary results lend a potential modifier role of the variant P108L in JSRP1 in MH susceptibility and further investigations are suggested to confirm these results.

Keywords: JSRP1, malignant hyperthermia, RyR1, skeletal muscle

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8963 Effect of Leptin Gene Methylation on Colorectal Cancer Chemoresistance

Authors: Wissem Abdaoui, Nizar M. Mhaidat, Ilhem Mokhtari, Adel Gouri

Abstract:

Colorectal cancer (CRC) is one of the most common tumors all over the world. Obesity, considered a risk factor of CRC, is characterized by a high level of secreted cytokines from adipose tissue. Among these inflammatory molecules, leptin is considered the key mediator for CRC cancer development and progression by activation of mitogenic and anti apoptotic signaling pathways. Gene expression can be significantly modulated by alterations in DNA methylation patterns. The aim of this study is to investigate the impact of leptin gene methylation on CRC prognosis and sensitivity to chemotherapy. The study involved 70 CRC tissue samples collected from King Abdullah University Hospital (KAUH) from which only 53 was analyzed because of bisulfate fragmentation and low yield of DNA extracted from FFPE tissues. A total of 22 blood samples were collected from healthy volunteers and enrolled as a control group. Leptin promoter methylation was analyzed by methylation specific PCR after bisulfate conversion. Results revealed that the incidence of leptin gene methylation was significantly higher in CRC patients in comparison to that of controls (P < 0.05). The correlation between patient’s demographics and leptin gene methylation was not significant (P < 0.05). However, a significant correlation between leptin gene methylation status and early cancer stages (I, II and III) was found in male but not in female (p < 0.05). Moreover, a significant correlation was found between leptin promoter methylation and early tumor localization T1-2 (p < 0.05). The correlation between epigenetic regulation of leptin and chemosensitivity was not significant. Taken together, these results suggest the possibility to use leptin gene methylation as a biomarker for the evaluation of CRC prognosis and metastasis.

Keywords: colorectal cancer, obesity, leptin, DNA methylation, disease prognosis, bisulfate conversion, chemoresistance

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8962 Comparison Study of 70% Ethanol Effect on Direct and Retrival Culture of Contaminated Umblical Cord Tissue for Expansion of Mesenchymal Stem Cells

Authors: Ganeshkumar, Ashika, Valavan, Ramesh, Thangam, Chirayu

Abstract:

MSCs are found in much higher concentration in the Wharton’s jelly compared to the umbilical cord blood, which is a rich source of hematopoietic stem cells. Umbilical cord tissue is collected at the time of birth; it is processed and stored in liquid nitrogen for future therapeutical purpose. The source of contamination might be either from vaginal tract of mother or from hospital environment or from personal handling during cord tissue sample collection. If the sample were contaminated, decontamination procedure will be done with 70% ethanol (1 minute) in order to avoid sample rejection. Ethanol is effective against a wide range of bacteria, protozoa and fungi and has low toxicity to humans. Among the 1954 samples taken for the study, 24 samples were found to be contaminated with microorganism. The organisms isolated from the positive samples were found to be E. coli, Stenotrophomonas maltophilia, Pseudomonas aueroginosa, Enterococcus fecalis, Acinetobacter bowmani, Staphylococcus epidermidis, Enterobacter cloacae, and Proteus mirabilis. Among these organisms 70% ethanol successfully eliminated E. coli, Enterococcus fecalis, Acinetobacter bowmani, Staphylococcus epidermidis, and Proteus mirabilis. 70% ethanol was unsuccessful in eliminating Stenotrophomonas maltophilia, Pseudomonas aueroginosa, and Enterobacter cloacae. Stenotrophomonas maltophilia and Pseudomonas aueroginosa have the ability to form biofilm that make them resistant to alcohol. Biofilm act as protective layer for bacteria and which protects them from host defense and antibiotic wash. Finally it was found 70% ethanol wash saved 58.3% cord tissue samples from rejection and it is ineffective against 41% of the samples. The contamination rate can be reduced by maintaining proper aseptic techniques during sample collection and processing.

Keywords: umblical cord tissue, decontamination, 70% ethanol effectiveness, contamination

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8961 Association of 105A/C IL-18 Gene Single Nucleotide Polymorphism with House Dust Mite Allergy in an Atopic Filipino Population

Authors: Eisha Vienna M. Fernandez, Cristan Q. Cabanilla, Hiyasmin Lim, John Donnie A. Ramos

Abstract:

Allergy is a multifactorial disease affecting a significant proportion of the population. It is developed through the interaction of allergens and the presence of certain polymorphisms in various susceptibility genes. In this study, the correlation of the 105A/C single nucleotide polymorphism (SNP) of the IL-18 gene and house dust mite-specific IgE among Filipino allergic and non-allergic population was investigated. Atopic status was defined by serum total IgE concentration of ≥100 IU/mL, while house dust mite allergy was defined by specific IgE value ≥ +1SD of IgE of nonatopic participants. Two hundred twenty match-paired Filipino cases and controls aged 6-60 were the subjects of this investigation. The level of total IgE and Specific IgE were measured using Enzyme-Linked Immunosorbent Assay (ELISA) while Polymerase Chain Reaction – Restriction Fragment Length Polymorphism (PCR-RFLP) analysis was used in the SNP detection. Sensitization profiles of the allergic patients revealed that 97.3% were sensitized to Blomia tropicalis, 40.0% to Dermatophagoides farinae, and 29.1% to Dermatophagoides pteronyssinus. Multiple sensitization to HDMs was also observed among the 47.27% of the atopic participants. Any of the allergy classes of the atopic triad were exhibited by the cases (allergic asthma: 48.18%; allergic rhinitis: 62.73%; atopic dermatitis: 19.09%), and two or all of these atopic states are concurrently occurring in 26.36% of the cases. A greater proportion of the atopic participants with allergic asthma and allergic rhinitis were sensitized to D. farinae, and D. pteronyssinus, while more of those with atopic dermatitis were sensitized to D. pteronyssinus than D. farinae. Results show that there is overrepresentation of the allele “A” of the 105A/C IL-18 gene SNP in both cases and control groups of the population. The genotype that predominate the population is the heterozygous “AC”, followed by the homozygous wild “AA”, and the homozygous variant “CC” being the least. The study confirmed a positive association between serum specific IgE against B. tropicalis and D. pteronyssinus and the allele “C” (Bt P=0.021, Dp P=0.027) and “AC” (Bt P=0.003, Dp P=0.026) genotype. Findings also revealed that the genotypes “AA” (OR:1.217; 95% CI: 0.701-2.113) and “CC” (OR, 3.5; 95% CI: 0.727-16.849) increase the risk of developing allergy. This indicates that the 105A/C IL-18 gene SNP is a candidate genetic marker for HDM allergy among Filipino patients.

Keywords: house dust mite allergy, interleukin-18 (IL-18), single nucleotide polymorphism,

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8960 Effects of Achillea millefolium L. Extract on Rat Spermatogenesis

Authors: Nasrin Takzaree, Gholamreza Hassanzadeh, Abbas Hadjiakhoondi, Mohammadreza Rouini

Abstract:

Introduction: Today herbal medicine are extensively used for various therapeutic reasons. Whereas Achillea millefolium L. comprises different chemical compounds it is used in classic and modern medicine for different purposes. Concerning the family planning as a principle matter, the idea of using specific herbal medicine is of great importance. Purpose: To investigate the effects of Achillea millefolium L. extract on fertility power and spermatogenesis process in male mature Wistar rats and the anti-fertility effects of this extract in male genital system. Material and methods: In this study 32 male mature Wistar rats were randomly divided in to 4 experimental groups. 1st experimental group included 8 rats receiving Achillea millefolium extract at the dose of 200 mg/kg intraperitoneally. Second and third groups received the extract the same at the doses of 400 and 800 mg/kg respectively. 4th group was considered as control group in which the parenteral distilled water was administered. after 20 days, rats were sacrificed and the spermatogenesis process was histologically examined. Results: In experimental groups receiving high doses of extract comparing with control group, thickness in seminiferous tubules basal membrane, decrease in germinal epithelium cells, congestion in testicular tissue, disarrangement in germinal epithelium cells as well as decrease in cellular condense were observed (p<0.001). Conclusion: Findings suggest that alcoholic extract of Achillea millefolium at high concentrations lead to the structural alterations and changes in spermatogenesis in testicular tissue.

Keywords: spermatogenesis, alcoholic extract of Achillea millefolium L., testis, Wistar rat

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8959 Identification of a Panel of Epigenetic Biomarkers for Early Detection of Hepatocellular Carcinoma in Blood of Individuals with Liver Cirrhosis

Authors: Katarzyna Lubecka, Kirsty Flower, Megan Beetch, Lucinda Kurzava, Hannah Buvala, Samer Gawrieh, Suthat Liangpunsakul, Tracy Gonzalez, George McCabe, Naga Chalasani, James M. Flanagan, Barbara Stefanska

Abstract:

Hepatocellular carcinoma (HCC), the most prevalent type of primary liver cancer, is the second leading cause of cancer death worldwide. Late onset of clinical symptoms in HCC results in late diagnosis and poor disease outcome. Approximately 85% of individuals with HCC have underlying liver cirrhosis. However, not all cirrhotic patients develop cancer. Reliable early detection biomarkers that can distinguish cirrhotic patients who will develop cancer from those who will not are urgently needed and could increase the cure rate from 5% to 80%. We used Illumina-450K microarray to test whether blood DNA, an easily accessible source of DNA, bear site-specific changes in DNA methylation in response to HCC before diagnosis with conventional tools (pre-diagnostic). Top 11 differentially methylated sites were selected for validation by pyrosequencing. The diagnostic potential of the 11 pyrosequenced probes was tested in blood samples from a prospective cohort of cirrhotic patients. We identified 971 differentially methylated CpG sites in pre-diagnostic HCC cases as compared with healthy controls (P < 0.05, paired Wilcoxon test, ICC ≥ 0.5). Nearly 76% of differentially methylated CpG sites showed lower levels of methylation in cases vs. controls (P = 2.973E-11, Wilcoxon test). Classification of the CpG sites according to their location relative to CpG islands and transcription start site revealed that those hypomethylated loci are located in regulatory regions important for gene transcription such as CpG island shores, promoters, and 5’UTR at higher frequency than hypermethylated sites. Among 735 CpG sites hypomethylated in cases vs. controls, 482 sites were assigned to gene coding regions whereas 236 hypermethylated sites corresponded to 160 genes. Bioinformatics analysis using GO, KEGG and DAVID knowledgebase indicate that differentially methylated CpG sites are located in genes associated with functions that are essential for gene transcription, cell adhesion, cell migration, and regulation of signal transduction pathways. Taking into account the magnitude of the difference, statistical significance, location, and consistency across the majority of matched pairs case-control, we selected 11 CpG loci corresponding to 10 genes for further validation by pyrosequencing. We established that methylation of CpG sites within 5 out of those 10 genes distinguish cirrhotic patients who subsequently developed HCC from those who stayed cancer free (cirrhotic controls), demonstrating potential as biomarkers of early detection in populations at risk. The best predictive value was detected for CpGs located within BARD1 (AUC=0.70, asymptotic significance ˂0.01). Using an additive logistic regression model, we further showed that 9 CpG loci within those 5 genes, that were covered in pyrosequenced probes, constitute a panel with high diagnostic accuracy (AUC=0.887; 95% CI:0.80-0.98). The panel was able to distinguish pre-diagnostic cases from cirrhotic controls free of cancer with 88% sensitivity at 70% specificity. Using blood as a minimally invasive material and pyrosequencing as a straightforward quantitative method, the established biomarker panel has high potential to be developed into a routine clinical test after validation in larger cohorts. This study was supported by Showalter Trust, American Cancer Society (IRG#14-190-56), and Purdue Center for Cancer Research (P30 CA023168) granted to BS.

Keywords: biomarker, DNA methylation, early detection, hepatocellular carcinoma

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8958 Molecular Characterization of Functional Domain (LRR) of TLR9 Genes in Malnad Gidda Cattle and Their Comparison to Cross Breed Cattle

Authors: Ananthakrishna L. R., Ramesh D., Kumar Wodeyar, Kotresh A. M., Gururaj P. M.

Abstract:

Malnad Gidda is the indigenous recognized cattle breed of Shivamogga District of Karnataka state, India is known for its disease resistance to many of the infectious diseases. There are 25 LRR (Leucine Rich Repeats) identified in bovine (Bos indicus) TLR9. The amino acid sequence of LRR is deduced to nucleotide sequence in BLASTx bioinformatic online tools. LRR2 to LRR10 are involved in pathogen recognition and binding in human TLR9 which showed a higher degree of nucleotide variations with respect to disease resistance to various pathogens. Hence, primers were designed to amplify the flanking sequences of LRR2 to LRR10, to discover the nucleotide variations if any, in Malnad Gidda breed of Cattle which is associated with disease resistance. The DNA isolated from peripheral blood mononuclear cells of ten Malnad Gidda cattle. A desired and specific amplification product of 0.8 kb was obtained at an annealing temperature of 56.6ᵒC. All the PCR products were sequenced on both sides by gene-specific primers. The sequences were compared with TLR9 sequence of cross breed cattle obtained from NCBI data bank. The sequence analysis between Malnad Gidda and crossbreed cattle revealed no nucleotide variations in the region LRR2 to LRR9 which shows the conserved in pathogen binding domain (LRR) of TLR9.

Keywords: leucine rich repeats, Malnad Gidda, cross breed, TLR9

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8957 Determination of Prostate Specific Membrane Antigen (PSMA) Based on Combination of Nanocomposite Fe3O4@Ag@JB303 and Magnetically Assisted Surface Enhanced Raman Spectroscopy (MA-SERS)

Authors: Zuzana Chaloupková, Zdeňka Marková, Václav Ranc, Radek Zbořil

Abstract:

Prostate cancer is now one of the most serious oncological diseases in men with an incidence higher than that of all other solid tumors combined. Diagnosis of prostate cancer usually involves detection of related genes or detection of marker proteins, such as PSA. One of the new potential markers is PSMA (prostate specific membrane antigen). PSMA is a unique membrane bound glycoprotein, which is considerably overexpressed on prostate cancer as well as neovasculature of most of the solid tumors. Commonly applied methods for a detection of proteins include techniques based on immunochemical approaches, including ELISA and RIA. Magnetically assisted surface enhanced Raman spectroscopy (MA-SERS) can be considered as an interesting alternative to generally accepted approaches. This work describes a utilization of MA-SERS in a detection of PSMA in human blood. This analytical platform is based on magnetic nanocomposites Fe3O4@Ag, functionalized by a low-molecular selector labeled as JB303. The system allows isolating the marker from the complex sample using application of magnetic force. Detection of PSMA is than performed by SERS effect given by a presence of silver nanoparticles. This system allowed us to analyze PSMA in clinical samples with limits of detection lower than 1 ng/mL.

Keywords: diagnosis, cancer, PSMA, MA-SERS, Ag nanoparticles

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8956 Hounsfield-Based Automatic Evaluation of Volumetric Breast Density on Radiotherapy CT-Scans

Authors: E. M. D. Akuoko, Eliana Vasquez Osorio, Marcel Van Herk, Marianne Aznar

Abstract:

Radiotherapy is an integral part of treatment for many patients with breast cancer. However, side effects can occur, e.g., fibrosis or erythema. If patients at higher risks of radiation-induced side effects could be identified before treatment, they could be given more individual information about the risks and benefits of radiotherapy. We hypothesize that breast density is correlated with the risk of side effects and present a novel method for automatic evaluation based on radiotherapy planning CT scans. Methods: 799 supine CT scans of breast radiotherapy patients were available from the REQUITE dataset. The methodology was first established in a subset of 114 patients (cohort 1) before being applied to the whole dataset (cohort 2). All patients were scanned in the supine position, with arms up, and the treated breast (ipsilateral) was identified. Manual experts contour available in 96 patients for both the ipsilateral and contralateral breast in cohort 1. Breast tissue was segmented using atlas-based automatic contouring software, ADMIRE® v3.4 (Elekta AB, Sweden). Once validated, the automatic segmentation method was applied to cohort 2. Breast density was then investigated by thresholding voxels within the contours, using Otsu threshold and pixel intensity ranges based on Hounsfield units (-200 to -100 for fatty tissue, and -99 to +100 for fibro-glandular tissue). Volumetric breast density (VBD) was defined as the volume of fibro-glandular tissue / (volume of fibro-glandular tissue + volume of fatty tissue). A sensitivity analysis was performed to verify whether calculated VBD was affected by the choice of breast contour. In addition, we investigated the correlation between volumetric breast density (VBD) and patient age and breast size. VBD values were compared between ipsilateral and contralateral breast contours. Results: Estimated VBD values were 0.40 (range 0.17-0.91) in cohort 1, and 0.43 (0.096-0.99) in cohort 2. We observed ipsilateral breasts to be denser than contralateral breasts. Breast density was negatively associated with breast volume (Spearman: R=-0.5, p-value < 2.2e-16) and age (Spearman: R=-0.24, p-value = 4.6e-10). Conclusion: VBD estimates could be obtained automatically on a large CT dataset. Patients’ age or breast volume may not be the only variables that explain breast density. Future work will focus on assessing the usefulness of VBD as a predictive variable for radiation-induced side effects.

Keywords: breast cancer, automatic image segmentation, radiotherapy, big data, breast density, medical imaging

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8955 Multilocus Phylogenetic Approach Reveals Informative DNA Barcodes for Studying Evolution and Taxonomy of Fusarium Fungi

Authors: Alexander A. Stakheev, Larisa V. Samokhvalova, Sergey K. Zavriev

Abstract:

Fusarium fungi are among the most devastating plant pathogens distributed all over the world. Significant reduction of grain yield and quality caused by Fusarium leads to multi-billion dollar annual losses to the world agricultural production. These organisms can also cause infections in immunocompromised persons and produce the wide range of mycotoxins, such as trichothecenes, fumonisins, and zearalenone, which are hazardous to human and animal health. Identification of Fusarium fungi based on the morphology of spores and spore-forming structures, colony color and appearance on specific culture media is often very complicated due to the high similarity of these features for closely related species. Modern Fusarium taxonomy increasingly uses data of crossing experiments (biological species concept) and genetic polymorphism analysis (phylogenetic species concept). A number of novel Fusarium sibling species has been established using DNA barcoding techniques. Species recognition is best made with the combined phylogeny of intron-rich protein coding genes and ribosomal DNA sequences. However, the internal transcribed spacer of (ITS), which is considered to be universal DNA barcode for Fungi, is not suitable for genus Fusarium, because of its insufficient variability between closely related species and the presence of non-orthologous copies in the genome. Nowadays, the translation elongation factor 1 alpha (TEF1α) gene is the “gold standard” of Fusarium taxonomy, but the search for novel informative markers is still needed. In this study, we used two novel DNA markers, frataxin (FXN) and heat shock protein 90 (HSP90) to discover phylogenetic relationships between Fusarium species. Multilocus phylogenetic analysis based on partial sequences of TEF1α, FXN, HSP90, as well as intergenic spacer of ribosomal DNA (IGS), beta-tubulin (β-TUB) and phosphate permease (PHO) genes has been conducted for 120 isolates of 19 Fusarium species from different climatic zones of Russia and neighboring countries using maximum likelihood (ML) and maximum parsimony (MP) algorithms. Our analyses revealed that FXN and HSP90 genes could be considered as informative phylogenetic markers, suitable for evolutionary and taxonomic studies of Fusarium genus. It has been shown that PHO gene possesses more variable (22 %) and parsimony informative (19 %) characters than other markers, including TEF1α (12 % and 9 %, correspondingly) when used for elucidating phylogenetic relationships between F. avenaceum and its closest relatives – F. tricinctum, F. acuminatum, F. torulosum. Application of novel DNA barcodes confirmed the fact that F. arthrosporioides do not represent a separate species but only a subspecies of F. avenaceum. Phylogeny based on partial PHO and FXN sequences revealed the presence of separate cluster of four F. avenaceum strains which were closer to F. torulosum than to major F. avenaceum clade. The strain F-846 from Moldova, morphologically identified as F. poae, formed a separate lineage in all the constructed dendrograms, and could potentially be considered as a separate species, but more information is needed to confirm this conclusion. Variable sites in PHO sequences were used for the first-time development of specific qPCR-based diagnostic assays for F. acuminatum and F. torulosum. This work was supported by Russian Foundation for Basic Research (grant № 15-29-02527).

Keywords: DNA barcode, fusarium, identification, phylogenetics, taxonomy

Procedia PDF Downloads 301