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41.
Keratin 8/18, the predominant keratin pair of simple epithelia, is known to be aberrantly expressed in several squamous cell carcinomas (SCCs), where its expression is often correlated with increased invasion, neoplastic progression, and poor prognosis. The majority of keratin 8/18 structural and regulatory functions are governed by posttranslational modifications, particularly phosphorylation. Apart from filament reorganization, cellular processes including cell cycle, cell growth, cellular stress, and apoptosis are known to be orchestrated by K8 phosphorylation at specific residues in the head and tail domains. Even though deregulation of K8 phosphorylation at two significant sites (Serine73/Serine431) has been implicated in neoplastic progression of SCCs by various in vitro studies, including ours, it is reported to be highly context-dependent. Therefore, to delineate the precise role of Kereatin 8 phosphorylation in cancer initiation and progression, we have developed the tissue-specific transgenic mouse model expressing Keratin 8 wild type and phosphodead mutants under Keratin 14 promoter. Subjecting these mice to 7,12-dimethylbenz(a)anthracene/12-O-tetradecanoylphorbol-13-acetate-mediated skin carcinogenesis revealed that Keratin 8 phosphorylation may lead to an early onset of tumors compared to Keratin 8 wild-type expressing mice. Conclusively, the transgenic mouse model developed in the present study ascertained a positive impact of Keratin 8 phosphorylation on the neoplastic transformation of skin-squamous cells.  相似文献   
42.

Current scenario in communicable diseases has generated new era that identifies the “One health” approach to understand the sharing and management of etiological agents with its impact on ecosystem. Under this context the relevance of zoonotic diseases generates major concern. The indiscriminate and higher use of antibiotics in animal husbandry creates substantial pressure on the gut microbiome for development of resistance due to shorter generation time and high density. Thus, gut works as a bioreactor for the breeding of ARBs in this scenario and are continuously released in different niches. These ARBs transfer resistance genes among native flora through horizontal gene transfer events, vectors and quorum sensing. About 60% of infectious diseases in human are caused by zoonotic pathogens have potential to carry ARGs which could be transmitted to humans. The well documented zoonotic diseases are anthrax cause by Bacillus anthracis, bovine tuberculosis by Mycobacterium tuberculosis, brucellosis by Brucella abortus, and hemorrhagic colitis by Escherichia coli. Similarly, most of the antibiotics are not completely metabolized and released in unmetabolized forms which enters the food chain and affect various ecological niches through bioaccumulation. The persistence period of antibiotics ranges from?<?1 to 3466 days in environment. The consequences of misusing the antibiotic in livestock and their fate in various ecological niches have been discussed in this review. Further the light sheds on antibiotics persistence and it biodegradation through different abiotic and biotic approaches in environment. The knowledge on personnel hygiene and strong surveillance system for zoonotic disease including ARBs transmission, prevention and control measures should be established to regulate the spread of AMR in the environment and subsequently to the human being through a food web.

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43.
Recent studies have used dense markers to examine the human genome in ancestrally homogeneous populations for hallmarks of selection. No genomewide studies have focused on recently admixed groups--populations that have experienced admixing among continentally divided ancestral populations within the past 200-500 years. New World admixed populations are unique in that they represent the sudden confluence of geographically diverged genomes with novel environmental challenges. Here, we present a novel approach for studying selection by examining the genomewide distribution of ancestry in the genetically admixed Puerto Ricans. We find strong statistical evidence of recent selection in three chromosomal regions, including the human leukocyte antigen region on chromosome 6p, chromosome 8q, and chromosome 11q. Two of these regions harbor genes for olfactory receptors. Interestingly, all three regions exhibit deficiencies in the European-ancestry proportion.  相似文献   
44.
p38 mitogen-activated protein kinase (MAPK) activates a number of heat shock proteins (HSPs), including HSP27 and alpha(B)-crystallin, in response to stress. Activation of HSP27 or alpha(B)-crystallin is known to protect organs/cells by increasing the stability of actin microfilaments. Although our previous studies showed that 17beta-estradiol (E(2)) improves cardiovascular function after trauma-hemorrhage, whether the salutary effects of E(2) under those conditions are mediated via p38 MAPK remains unknown. Male rats (275-325 g body wt) were subjected to soft tissue trauma and hemorrhage (35-40 mmHg mean blood pressure for approximately 90 min) followed by fluid resuscitation. At the onset of resuscitation, rats were injected intravenously with vehicle, E(2) (1 mg/kg body wt), E(2) + the p38 MAPK inhibitor SB-203580 (2 mg/kg body wt), or SB-203580 alone, and various parameters were measured 2 h thereafter. Cardiac functions that were depressed after trauma-hemorrhage were returned to normal levels by E(2) administration, and phosphorylation of cardiac p38 MAPK, HSP27, and alpha(B)-crystallin was increased. The E(2)-mediated improvement of cardiac function and increase in p38 MAPK, HSP27, and alpha(B)-crystallin phosphorylation were abolished with coadministration of SB-203580. These results suggest that the salutary effect of E(2) on cardiac function after trauma-hemorrhage is in part mediated via upregulation of p38 MAPK and subsequent phosphorylation of HSP27 and alpha(B)-crystallin.  相似文献   
45.
Mammalian oocytes are deficient in their ability to carry out glycolysis. Therefore, the products of glycolysis that are necessary for oocyte development are provided to oocytes by companion cumulus cells. Mouse oocytes secrete paracrine factors that promote glycolysis in cumulus cells. The objective of this study was to identify paracrine factors secreted by oocytes that promote glycolysis and expression of mRNA encoding the glycolytic enzymes PFKP and LDHA. Candidates included growth differentiation factor 9 (GDF9), bone morphogenetic protein 15 (BMP15) and fibroblast growth factors (FGFs). Bmp15-/- and Gdf9+/- Bmp15-/- (double mutant, DM) cumulus cells exhibited reduced levels of both glycolysis and Pfkp and Ldha mRNA, and mutant oocytes were deficient in promoting glycolysis and expression of Pfkp and Ldha mRNA in cumulus cells of wild-type (WT) mice. Alone, neither recombinant BMP15, GDF9 nor FGF8 promoted glycolysis and expression of Pfkp and Ldha mRNA in WT cumulus cells. Co-treatment with BMP15 and FGF8 promoted glycolysis and increased expression of Pfkp and Ldha mRNA in WT cumulus cells to the same levels as WT oocytes; however, the combinations of BMP15/GDF9 or GDF9/FGF8 did not. Furthermore, SU5402, an FGF receptor-dependent protein kinase inhibitor, inhibited Pfkp and Ldha expression in cumulus cells promoted by paracrine oocyte factors. Therefore, oocyte-derived BMP15 and FGFs cooperate to promote glycolysis in cumulus cells.  相似文献   
46.
47.
Dye׳s residues in textile effluents are hazardous for humans and animals health. Such pollutants can be degraded into non-harmful molecules using biological approaches that are considered cheaper and ecologically safer. Isolated 15 bacterial cultures from soil that could be used in biological system were showed decolorization capacity for Acid Green dye (33.9% to 94.0%) using thin layer chromatography and broth culture method. The most promising cultures (AMC3) to decolorize Acid green Dye (94.6%) was re-coded as NSDSUAM for submitting at IMTECH, Chandigarh for sequencing. The 16SrRNA sequencing suggested that it can be a variant of Pseudomonas geniculata (99.85% identical similarity) with difference of 2 base pairs to reference strain Pseudomonas geniculata ATCC 19374(T). Thus present study proposed dye decolorizing efficiency of the isolated strain of Pseudomonas geniculata that was previously unnoticed. The sequence is deposited in NCBI GenBank with the accession number KP238100.  相似文献   
48.
49.
Photic entrainment of animals in the field is basically attributed to their exposure to the dimly lit nights flanked by the dawn and dusk twilight transitions. This implicates the functional significance of the dimly lit nights as that of the twilight transitions. Recently, the authors have demonstrated that the dimly lit night at 0.0006 lux altered the attributes of the circadian rhythm of locomotor activity of Drosophila jambulina. The present study examined whether the durations of such dimly lit nights affect the entrainment and free-running rhythmicity of D. jambulina. Flies were subjected for 10 days to two types of 24-h lighting regimes in which the photophase (L) was at 10 lux for all flies but the scotophase, which varied in duration from 9 to 15 h, was either at 0 lux (D phase) for control flies or 0.0006 lux (the artificial starlight or S phase) for experimental flies. Thereafter, they were transferred to constant darkness (DD) to compare the after-effects of the dimly lit nights on the period (τ) of free-running rhythm in DD with that of the completely dark nights. Control flies were entrained by all LD cycles, but the experimental flies were entrained only by five LS cycles in which the duration of the S phases ranged from 10 to 14 h. The two LS cycles with very short (9 h) and long (15 h) S phases rendered the flies completely arrhythmic. Control flies started activity shortly before lights-on and continued well after lights-off. The experimental flies, however, commenced activity several hours prior to lights-on but ended activity abruptly at lights-off as the result of a negative masking effect of nocturnal illumination. Length of the midday rest was considerably shorter in the control than in the experimental flies in each lighting regime. The active phase in the control flies was predictably shortened; nonetheless, it was invariable in the experimental flies as the nights lengthened. Transfer from lighting regimes to DD initiated robust free-running rhythmicity in all flies including the arrhythmic ones subjected to LS cycles with 9 and 15 h of scotophases. The τ was profoundly affected by the nocturnal irradiance of the prior entraining lighting regime, as it was always shorter in the experimental than in the control flies. Thus, these results indisputably demonstrate the changes in fundamental properties of the circadian pacemaker of D. jambulina were solely attributed to the extremely dim nocturnal irradiance. This strain of D. jambulina is entrained essentially by the dimly lit natural nights, since it is never exposed to the prevailing photic cues such as the twilight transitions or bright photoperiod, owing to the dense vegetation of its habitat.  相似文献   
50.
Cyclooxygenase-2 (COX-2), an inducible enzyme, has been implicated in the progression and angiogenesis of breast cancer. The aim of the study is to quantify the concentration of COX-2 and its association with clinico-pathological parameters and response to treatment in patients with invasive ductal carcinoma receiving both neo-adjuvant and adjuvant chemotherapy. The level of COX-2 was estimated using a novel biosensor-based surface plasmon resonance technique in serum of 84 patients with breast cancer (48 patients of neo-adjuvant chemotherapy and 36 patients of adjuvant chemotherapy) and 40 age- and gender-matched normal individuals. A significant increase in COX-2 level was observed in patients compared with normal individuals (p>0.0001). The COX-2 level in serum was found to be significantly higher in patients with lymph node involvement (p<0.0061). 68% (33/48) of the patients receiving neo-adjuvant chemotherapy showed significantly (p<0.0025) reduced COX-2 levels. This study shows significant decrease of COX-2 level in patients with breast cancer treated with both neo-adjuvant and adjuvant chemotherapy. Estimation of COX-2 level in serum may serve as a tumor biomarker in patients with breast cancer.  相似文献   
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