Electrical conductive properties of some composites of gum arabic biopolymer and magnetite nanoparticles

DC electrical conductive properties of some composites of gum arabic biopolymer (host) and magnetite nanoparticles (guest) synthesized in different weight percentages have been studied as a function of temperature and applied bias voltage to explore the effect of the guest on the electrical conduction of the host. Two types of trap distributions (single discrete and exponential) have been found in these composites. The observed results show that the conductivity of the composites increases with increasing guest content along with a decrease in activation energy. Percolation theory has been employed for the analysis of the room temperature electrical conductivity enhancement with the variation of guest content. The activation energy and the pre-exponential factor values estimated following Arrhenius relation satisfies the compensation law

Redescription of Oligodon arnensis, Shaw, 1802 (Reptilia: Colubridae) collected from Birbhum, West Bengal, India

Oligodon arnensis, Shaw, 1802 commonly known as kukri snake, a semi- fossorial snake species is taken for study as it is a most challenging group of snake. A morphometric study on several aspects like the number of supra-labials , infra-labials, ventrals, dorsals, distance between eye to nostril, eye diameter, number of bands, shape of banding etc. are reported. A significant correlation is present in between snout-vent length and tail length and in between eye diameter and distance from eye to nostril a possible explanation of large eye size related to habitat is given in the study

Interval valued (\in,\ivq)-fuzzy filters of pseudo BLBL-algebras

We introduce the concept of quasi-coincidence of a fuzzy interval value with an interval valued fuzzy set. By using this new idea, we introduce the notions of interval valued (\in,\ivq)-fuzzy filters of pseudo $BL$-algebras and investigate some of their related properties. Some characterization theorems of these generalized interval valued fuzzy filters are derived. The relationship among these generalized interval valued fuzzy filters of pseudo $BL$-algebras is considered. Finally, we consider the concept of implication-based interval valued fuzzy implicative filters of pseudo $BL$-algebras, in particular, the implication operators in Lukasiewicz system of continuous-valued logic are discussed

Improvement of low grade ejaculates of Holstein Friesian crossbred bulls by different filtration techniques for cryopreservation

To improve the quality of poor ejaculates, sephadex (FS) and sephadex with ion-exchangers (FS+IE) filtration were used to examine split samples of 18 ejaculates of 6 Karan Fries bulls at various stages of cryopreservation. Data were analyzed using analysis of variance. All semen quality traits improved in both the filtration and further superiority of FS+IE column was observed due to its better efficacy of trapping immotile, dead and abnormal spermatozoa as well as there was decrease in sperm concentration, tail and total abnormalities. The initial, prefreeze and post-thaw motility, viability, sperm cells with intact plasma membranes and sperms with normal acrosomes of FS+IE filtrates were significantly better than the nonfiltered and FS filtered semen samples during different stages of cryopreservation. Therefore, it can be concluded that better quality semen can be harvested from poor ejaculates through FS+IE and FS filtration to improve fertilization potential of the spermatozoa

Improvement of sexual behavior and semen quality by therapeutic approach and zinc supplementation on Karan Fries

Sub-fertility is one of the major concerns in crossbred bulls as 42.98% bulls are getting culled due to sub- fertility problems therefore, a study was planned on 18 Karan Fries bulls producing poor quality semen or not mounted. They were randomly grouped into 3 treatment groups of 6 animals each and 2 normal bulls were kept as control. Sexual behavior and semen quality were studied during pre-therapy (1 month), therapy (90 days) and post- therapy (90 days) period. Data were analyzed using ANOVA. During therapy period, first group treated with 10 g of herbal product orally, second group with 0.0082 mg of GnRH intramuscularly at 10 days interval and third group with 80 ppm of zinc for 90 days for each group. The results depicted that herbal and GnRH treatment significantly reduced the reaction time, whereas herbal, GnRH treatment and zinc supplementation significantly improved the libido score and reduced per cent of non-mounts during the therapy and post-therapy period. The volume of semen and level of testosterone improved in all treatments groups. Herbal, GnRH treatment and zinc supplementation increased the average number of good and medium quality ejaculates/month/bull and maximum efficiency achieved during the treatment period. There was increase in percent live sperm and decrease in abnormality in herbal treated and zinc supplemented group. Therefore, it can be concluded that GnRH therapy, herbal treatment and zinc supplementation will be effective to overcome the sub-fertility problem in crossbred bulls

Acetylation Regulates WRN Catalytic Activities and Affects Base Excision DNA Repair

Background: The Werner protein (WRN), defective in the premature aging disorder Werner syndrome, participates in a number of DNA metabolic processes, and we have been interested in the possible regulation of its function in DNA repair by post-translational modifications. Acetylation mediated by histone acetyltransferases is of key interest because of its potential importance in aging, DNA repair and transcription. Methodology/Principal Findings: Here, we have investigated the p300 acetylation mediated changes on the function of WRN in base excision DNA repair (BER). We show that acetylation of WRN increases in cells treated with methyl methanesulfonate (MMS), suggesting that acetylation of WRN may play a role in response to DNA damage. This hypothesis is consistent with our findings that acetylation of WRN stimulates its catalytic activities in vitro and in vivo, and that acetylated WRN enhances pol b-mediated strand displacement DNA synthesis more than unacetylated WRN. Furthermore, we show that cellular exposure to the histone deacetylase inhibitor sodium butyrate stimulates long patch BER in wild type cells but not in WRN depleted cells, suggesting that acetylated WRN participates significantly in this process. Conclusion/Significance: Collectively, these results provide the first evidence for a specific role of p300 mediated WRN acetylation in regulating its function during BER

O6-methylguanine-DNA-methyltransferase expression and gene polymorphisms in relation to chemotherapeutic response in metastatic melanoma

In a retrospective study, O6-methylguanine-DNA-methyltransferase (MGMT) expression was analysed by immunohistochemistry using monoclonal human anti-MGMT antibody in melanoma metastases in patients receiving dacarbazine (DTIC) as single-drug therapy or as part of combination chemotherapy with DTIC–vindesine or DTIC–vindesine–cisplatin. The correlation of MGMT expression levels with clinical response to chemotherapy was investigated in 79 patients with metastatic melanoma. There was an inverse relationship between MGMT expression and clinical response to DTIC-based chemotherapy (P=0.05). Polymorphisms in the coding region of the MGMT gene were also investigated in tumours from 52 melanoma patients by PCR/SSCP and nucleotide sequence analyses. Single-nucleotide polymorphisms (SNPs) in exon 3 (L53L and L84F) and in exon 5 (I143V/K178R) were identified. There were no differences in the frequencies of these polymorphisms between these melanoma patients and patients with familial melanoma or healthy Swedish individuals. Functional analysis of variants MGMT-I143V and -I143V/K178R was performed by in vitro mutagenesis in Escherichia coli. There was no evidence that these variants decreased the MGMT DNA repair activity compared to the wild-type protein. All melanoma patients with the MGMT 53/84 polymorphism except one had tumours with high MGMT expression. There was no significant correlation between any of the MGMT polymorphisms and clinical response to chemotherapy, although an indication of a lower response rate in patients with SNPs in exon 5 was obtained. Thus, MGMT expression appears to be more related to response to chemotherapy than MGMT polymorphisms in patients with metastatic melanoma

Development and evaluation of human AP endonuclease inhibitors in melanoma and glioma cell lines

AimsModulation of DNA base excision repair (BER) has the potential to enhance response to chemotherapy and improve outcomes in tumours such as melanoma and glioma. APE1, a critical protein in BER that processes potentially cytotoxic abasic sites (AP sites), is a promising new target in cancer. In the current study, we aimed to develop small molecule inhibitors of APE1 for cancer therapy.MethodsAn industry-standard high throughput virtual screening strategy was adopted. The Sybyl8.0 (Tripos, St Louis, MO, USA) molecular modelling software suite was used to build inhibitor templates. Similarity searching strategies were then applied using ROCS 2.3 (Open Eye Scientific, Santa Fe, NM, USA) to extract pharmacophorically related subsets of compounds from a chemically diverse database of 2.6 million compounds. The compounds in these subsets were subjected to docking against the active site of the APE1 model, using the genetic algorithm-based programme GOLD2.7 (CCDC, Cambridge, UK). Predicted ligand poses were ranked on the basis of several scoring functions. The top virtual hits with promising pharmaceutical properties underwent detailed in vitro analyses using fluorescence-based APE1 cleavage assays and counter screened using endonuclease IV cleavage assays, fluorescence quenching assays and radiolabelled oligonucleotide assays. Biochemical APE1 inhibitors were then subjected to detailed cytotoxicity analyses.ResultsSeveral specific APE1 inhibitors were isolated by this approach. The IC(50) for APE1 inhibition ranged between 30 nM and 50 μM. We demonstrated that APE1 inhibitors lead to accumulation of AP sites in genomic DNA and potentiated the cytotoxicity of alkylating agents in melanoma and glioma cell lines.ConclusionsOur study provides evidence that APE1 is an emerging drug target and could have therapeutic application in patients with melanoma and glioma

The association of APE1 −656T > G and 1349 T > G polymorphisms and cancer risk: a meta-analysis based on 37 case-control studies

<p>Abstract</p> <p>Background</p> <p>APE1 (apurinic/apyrimidinic endonuclease 1) is an important DNA repair protein in the base excision repair pathway. Polymorphisms in <it>APE1 </it>have been implicated in susceptibility to cancer; however, results from the published studies remained inconclusive. The objective of this study was to conduct a meta-analysis investigating the association between polymorphisms in <it>APE1 </it>and the risk for cancer.</p> <p>Methods</p> <p>The PubMed and Embase databases were searched for case-control studies published up to June, 2011 that investigated <it>APE1 </it>polymorphisms and cancer risk. Odds ratios (ORs) and 95% confidence intervals (CIs) were used to assess the strength of the associations.</p> <p>Results</p> <p>Two polymorphisms (−656 T > G, rs1760944 and 1349 T > G, rs1130409) in 37 case-control studies including 15, 544 cancer cases and 21, 109 controls were analyzed. Overall, variant genotypes (GG and TG/GG) of −656 T > G polymorphism were associated with significantly decreased cancer risk in homozygote comparison (OR = 0.81, 95%CI: 0.67-0.97), dominant model comparison (OR = 0.89, 95%CI: 0.81-0.97) and recessive model comparison (OR = 0.90, 95%CI: 0.82-0.98), whereas the 1349 T > G polymorphism had no effects on overall cancer risk. In the stratified analyses for −656 T > G polymorphism, there was a significantly decreased risk of lung cancer and among Asian populations.</p> <p>Conclusions</p> <p>Although some modest bias could not be eliminated, the meta-analysis suggests that <it>APE1 −</it>656 T > G polymorphism has a possible protective effect on cancer risk particularly among Asian populations whereas 1349 T > G polymorphism does not contribute to the development of cancer.</p