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111.
As a serotonin antagonist, tropisetron positively affects blood glucose lowering, insulin synthesis, pancreas inflammation, and apoptosis in diabetes. Reproductive disorders are one of the diabetes-induced chronic complications. The present study aimed to evaluate the effect of tropisetron on diabetes-induced testicular inflammation, its signaling pathway, and mir146a. To this end, animals were assigned to the control, tropisetron, diabetes (DM), DM-tropisetron, and DM-glibenclamide groups. Streptozotocin (50 mg/kg) was intraperitoneally injected to provide diabetes. Tropisetron and glibenclamide were then administrated intraperitoneally for 2 weeks after diabetes induction. Testes histology, real-time polymerase chain reaction, western blot analysis, ELISA, and immunohistochemistry assays were also performed. The finding revealed that tropisetron significantly improved diabetes-induced testis damages, lowered TLR4, TRAF6, IRAK1, NF-κB, and caspase3 protein expressions, and decreased TNF-α and IL-1 levels. Moreover, the mir146a expression declined following the tropisetron treatment. This study demonstrated that the significant role of tropisetron in lowering testicular inflammation and apoptosis might have been due to the inhibition of the TLR4/IRAK1/TRAF6 signaling pathway and thereby the attenuation of NF-κB and caspase3 expression and inflammatory cytokines. Furthermore, the downregulation of mir146a, as an inflammatory microRNA interacting with TLR4, showed another pathway, through which tropisetron improved diabetes-induced testicular injuries.  相似文献   
112.
An infectious disease that is transmitted from animals to humans and vice-versa is called zoonosis. Bacterial zoonotic diseases can re-emerge after they have been eradicated or controlled and are among the world's major health problems which inflict tremendous burden on healthcare systems. The first step to encounter such illnesses can be early and precise detection of bacterial pathogens to further prevent the following losses due to their infections. Although conventional methods for diagnosing pathogens, including culture-based, polymerase chain reaction-based, and immunological-based techniques, benefit from their advantages, they also have their own drawbacks, for example, taking long time to provide results, and requiring laborious work, expensive materials, and special equipment in certain conditions. Consequently, there is a greater tendency to introduce simple, innovative, quicker, accurate, and low-cost detection methods to effectively characterize the causative agents of infectious diseases. Biosensors, therefore, seem to practically be one of those novel promising diagnostic tools on this aim. These are effective and reliable elements with high sensitivity and specificity, that their usability can even be improved in medical diagnostic systems when empowered by nanoparticles. In the present review, recent advances in the development of several bio and nano biosensors, for rapid detection of zoonotic bacteria, have been discussed in details.  相似文献   
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Numerous agents can damage the DNA of prokaryotes in the environment (e.g., reactive oxygen species, irradiation, and secondary metabolites such as antibiotics, enzymes, starvation, etc.). The large number of potential DNA-damaging agents, as well as their diverse modes of action, precludes a simple test of DNA damage based on detection of nucleic acid breakdown products. In this study, free 3'-OH DNA ends, produced by either direct damage or excision DNA repair, were used to assess DNA damage. Terminal deoxyribonucleotide transferase (TdT)-mediated dUTP nick end labeling (TUNEL) is a procedure in which 3'-OH DNA ends are enzymatically labeled with dUTP-fluorescein isothiocyanate using TdT. Cells labeled by this method can be detected using fluorescence microscopy or flow cytometry. TUNEL was used to measure hydrogen peroxide-induced DNA damage in the archaeon Haloferax volcanii and the bacterium Escherichia coli. DNA repair systems were implicated in the hydrogen peroxide-dependent generation of 3'-OH DNA ends by the finding that the protein synthesis inhibitors chloramphenicol and diphtheria toxin blocked TUNEL labeling of E. coli and H. volcanii, respectively. DNA damage induced by UV light and bacteriophage infection was also measured using TUNEL. This methodology should be useful in applications where DNA damage and repair are of interest, including mutant screening and monitoring of DNA damage in the environment.  相似文献   
115.
Rohwer F  Seguritan V  Choi DH  Segall AM  Azam F 《BioTechniques》2001,31(1):108-12, 114-6, 118
In the following report, thermal cycling coupled with random 10-mers as primers was used to construct randomly amplified shotgun libraries (RASLs). This approach allowed shotgun libraries to be constructed from nanogram quantities of input DNA. RASLs contained inserts from throughout a target genome in an unbiased fashion and did not appear to contain chimeric sequences. This protocol should be useful for shotgun sequencing the genomes of unculturable organisms and rapidly producing shotgun libraries from cosmids, fosmids, yeast artificial chromosomes (YACs), and bacterial artificial chromosomes (BACs).  相似文献   
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Ectohydrolytic enzyme activity (EEA) potential of 37 bacterial isolates derived from Orbicella annularis coral and 2 coral pathogens (Vibrio shilonii and V. coralliilyticus) was measured as model to infer the role of bacteria in organic matter processing within coral reef ecosystems. Bacterial cell-specific activities of eight enzyme types were measured after incubation in organic matter enriched and unenriched filtered seawater. Max value of activities of alkaline phosphatase, oleate-lipase, stearate-lipase and proteinase were 769.3, 327.6, 82.9 and 36.7 amol cell−1 h−1, respectively. Chitinase, α-mannosidase, α-glucosidase and β-glucosidase were generally lower by comparison (max 4.7–20.7 amol cell−1 h−1). No “super” isolates (bacteria expressing high levels of all ectohydrolases) were found suggesting a “specialization” among individual bacterial strains. Cumulatively, the 39 isolates tested displayed a broad range of cell-specific enzyme activities in both organic matter conditions. Culture-independent measurement of coral mucus layer EEA in O. annularis off a Panama reef showed comparable EEA patterns and diversity as the isolates. Volume-specific EEAs of all enzymes except alkaline phosphatase were 8–48 times higher in mucus than in surrounding seawater (SSW) samples. However, cell-specific EEAs in mucus were generally lower than in the SSW partly due to more abundant cells in the mucus than in SSW. For field samples, ≥ 85% of proteinase was cell-bound, while lipase was preferentially dissolved (40–96%). In general, the production of dissolved EEAs varied among measurements depending on sample source and enzyme types, suggesting a potential role of ectoenzyme size distribution in linking the whole reef ecosystem. Our findings support that the cumulative ectoenzyme expression (“ectoenzymome”) of the coral microbiome has the potential to maintain the functional resilience of the coral holobiont and response to stress through its contribution to organic matter processing within coral reef ecosystems.

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118.
In the present study we determined the association of angiotensin converting enzyme (ACE) and plasminogen activator inhibitor-1 (PAI-1) gene polymorphisms with diabetic retinopathy (DR) and its sub-clinical classes in Pakistani type 2 diabetic patients. A total of 353 diabetic subjects including 160 DR and 193 diabetic non retinopathy (DNR) as well as 198 healthy controls were genotyped by allele specific polymerase chain reaction (PCR) for ACE Insertion/Deletion (ID) polymorphism, rs4646994 in intron 16 and PAI-1 4G/5G (deletion/insertion) polymorphism, rs1799768 in promoter region of the gene. To statistically assess the genotype-phenotype association, multivariate logistic regression analysis was applied to the genotype data of DR, DNR and control individuals as well as the subtypes of DR. The ACE genotype ID was found to be significantly associated with DR (p = 0.009, odds ratio (OR) 1.870 [95% confidence interval (CI) = 1.04–3.36]) and its sub-clinical class non-proliferative DR (NPDR) (p = 0.006, OR 2.250 [95% CI = 1.098–4.620]), while PAI polymorphism did not show any association with DR in the current cohort. In conclusion in Pakistani population the ACE ID polymorphism was observed to be significantly associated with DR and NPDR, but not with the severe form of the disease i.e. proliferative DR (PDR).  相似文献   
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Over the past couple of decades there have been major advances in the field of nanoscience and nanotechnology. Many applications have sprouted from these fields of research. It is essential, given the scale of the materials, to attain accurate, valid and reproducible measurements. Material properties have shown to be a function of their size and composition. Physiochemical properties of the nanomaterials can significantly alter material behavior compared to bulk counterparts. For example, metal oxide nanoparticles have found broad applications ranging from photo-catalysis to antibacterial agents. In our study, we synthesized CuO nanoparticles using well established sol-gel based methods with varying levels of Ni doping. However, upon analysis of measured infrared data, we discovered the presence of quasi-periodic (QP) processes. Such processes have previously been reported to be tightly associated with measurement memory effects. We were able to detect the desired QP process in these measurements from three highly accurate repetitive experiments performed on each Ni (1–7%) doped CuO sample. In other words, successive measurements performed in a rather short period of time remember each other at least inside a group of neighboring measurements.  相似文献   
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