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11.
An aetiological role has been proposed for human papillomavirus (HPV) in skin carcinogenesis within the immunosuppressed patient population. To examine this possibility, we have focused on an HPV type that, to date, has been identified only in the cutaneous lesions of renal transplant recipients despite a high degree of sequence homology with other HPVs commonly found in warts in the general population. We report that the non-coding region of this virus, HPV type 77, contains a consensus binding site for the tumour suppressor protein p53, and we show by gel-retardation analysis that this sequence does indeed bind p53. Furthermore, using reporter gene assays, we demonstrate that HPV77 promoter activity is stimulated by UV radiation and that this response is mediated through the p53 binding site. This is the first report of a p53-dependent positive response element within a viral genome. Our results suggest a possible novel mechanism by which specific types of HPV might act as cofactors with UV radiation in cutaneous transformation.  相似文献   
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Human Vg9/Vδ2 T cells (γδ T cells) are immune surveillance cells both in innate and adaptive immunity and are a possible target for anticancer therapies, which can induce immune responses in a variety of cancers. Small non-peptide antigens such as zoledronate can do activation and expansion of T cells in vitro. It is evident that for adoptive cancer therapies, large numbers of functional cells are needed into cancer patients. Hence, optimization of methods needs to be carried out for the efficient expansion of these T cells. Standardization of peripheral blood mononuclear cells (PBMCs) isolation was devised. Cytokines (interleukin 2 (IL-2) and interleukin 15 (IL-15)) and zoledronate were also standardized for different concentrations. It was found that an increased number of PBMCs were recovered when washing was done at 1100 revolution per minute (rpm). Significantly high expansion fold was (2524 ± 787 expansion fold) achieved when stimulation of PBMCs was done with 1 µM of zoledronate and both cytokines IL-2 and IL-15 supported the expansion and survival of cells at the concentrations of 100 IU/ml and 10 ng/ml respectively. 14-day cultures showed highly pure (91.6 ± 5.1%) and live (96.5 ± 2.5%) expanded γδ T cells. This study aimed to standardize an easy to manipulate technique for the expansion of γδ T cells, giving a higher yield.  相似文献   
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Extracts prepared from liver, kidney, lung and brain of camel contain glutathione, glutathione S-transferase and glutathione reductase. Liver had the highest level of glutathione (218.7 mumol/g wet weight) whereas brain had the lowest level (66.4 mumol/g wet weight). The highest activity for glutathione reductase was found in the kidney (2.6 mumol/min/mg protein) while the lowest activity was found in the lung (0.9 mumol/min/mg protein). Glutathione S-transferase activity was the highest in liver (4.2 mumol/min/mg protein) and the lowest in brain (1 mumol/min/mg protein). Purified glutathione S-transferases from lung, kidney, brain and liver were similar in their molecular size, subunit composition as well as immuno-reactivity and showed some differences in their response to heat and inhibitors.  相似文献   
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Bayesian Estimation of the parameter of a distribution is considered using Ranked set sampling (RSS). It is shown that for at least one RSS plan, the Bayes estimator has smaller Bayes risk than the Bayes estimator using simple random sampling (SRS). Furthermore, for exponential family with conjugate prior, the Bayes estimator of the mean using balanced RSS dominates, in terms of its Bayes risk, the Bayes estimator of the mean using SRS. This procedure is used to estimate the average Milk yield of four hundreds and two sheep. The empirical efficiency supports the theoretical findings.  相似文献   
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A simple and environmentally friendly method was developed for smart and efficient waterborne polyurethane (PUR) paint. Sugarcane bagasse was recycled into reduced graphene oxide nanosheets (rGONSs). Both lanthanide-doped aluminate nanoparticles (LAN; photoluminescent agent, 7–9 nm) and rGONSs (reinforcement agent) were integrated into a waterborne polyurethane to produce a novel photoluminescent, hydrophobic, and anticorrosive nanocomposite coating. Using ferrocene-based oxidation under masked circumstances, graphene oxide nanosheets were produced from sugarcane bagasse. The oxidized semicarbazide (SCB) nanostructures were integrated into polyurethane coatings as a drying, anticorrosion, and crosslinking agent. Polyurethane coatings with varying amounts of phosphor pigment were prepared and subsequently applied to mild steel. The produced paints (LAN/rGONSs@PUR) were tested for their hydrophobicity, hardness, and scratch resistance. Commission Internationale de l'éclairage (CIE) Laboratory parameters and photoluminescence analysis established the opacity and colourimetric properties of the nanocomposite coatings. When excited at 365 nm, the luminescent transparent paints emitted a strong greenish light at 517 nm. The anticorrosion characteristics of the coated steel were investigated. The phosphor-containing (11% w/w) polyurethane coatings displayed the most pronounced anticorrosion capability and long-persistent luminosity. The prepared waterborne polyurethane paints were very photostable and durable.  相似文献   
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This study was conducted to evaluate the quality of water in selected dams in Albaha region, Kingdom of Saudi Arabia. Water samples from eight dams were subjected to physical, chemical, and bacteriological assessment using standardized procedures of conductivity, total dissolved solids, ions, acidity & alkalinity, and EC blue 100® coliform detection. About three fourth (75%) of dams’ water samples exceeded the permissible levels of pH, total dissolved solids, turbidity, Mn and NO3 set by Saudi standards. Average levels of total dissolved solids, Fe, Mn, SO4, NO3, and NO2 were 3065.00, 0.10, 0.89, 68.25, 17.91 and 0.016 mg/L, respectively. However, the average pH of water samples was 7.95 ± 0.66 which still within the accepted range set by national and global standards. Moreover, total dissolved solids also exceeded regular standards of Food and Agriculture Organization for irrigation water quality. Coliform bacteria were detected in 37.5% of dams without any significant spatial differences between dams and sites as groups. Correlations were found between pH & NO3, SO4 & NO3, coliform bacteria & turbidity, coliform bacteria & NO2 levels. Increased concentrations of assessed parameters in dams may be attributed to agricultural activities as well as animal and human wastes deposited into dams via rainfalls and flash floods. Proper treatment of dams needs to be taken into account before consumption and irrigation.  相似文献   
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Most chemical neurotransmission occurs through Ca2+-dependent evoked or spontaneous vesicle exocytosis. In both cases, Ca2+ sensing is thought to occur shortly before exocytosis. In this paper, we provide evidence that the Ca2+ dependence of spontaneous vesicle release may partly result from an earlier requirement of Ca2+ for the assembly of soluble N-ethylmaleimide–sensitive fusion attachment protein receptor (SNARE) complexes. We show that the neuronal vacuolar-type H+-adenosine triphosphatase V0 subunit a1 (V100) can regulate the formation of SNARE complexes in a Ca2+–Calmodulin (CaM)-dependent manner. Ca2+–CaM regulation of V100 is not required for vesicle acidification. Specific disruption of the Ca2+-dependent regulation of V100 by CaM led to a >90% loss of spontaneous release but only had a mild effect on evoked release at Drosophila melanogaster embryo neuromuscular junctions. Our data suggest that Ca2+–CaM regulation of V100 may control SNARE complex assembly for a subset of synaptic vesicles that sustain spontaneous release.  相似文献   
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BackgroundPhysicians are considered to be a high-risk population for a poor quality of life (QoL), but few studies of lifestyle factors include the QoL among them.ObjectivesThis study aimed to investigate the relationship between lifestyle factors and a positive QoL among primary health care (PHC) physicians.MethodsA cross-sectional study was conducted at 20 primary healthcare centers in Madinah, Saudi Arabia. A self-administered questionnaire was used, including sociodemographic characteristics, lifestyle data, and the short version of the World Health Organization Quality of Life questionnaire. Appropriate statistical analyses were used, including multivariate logistic regression models.ResultsThe response rate was 85.7% (72/84) physicians. The mean score of the total QoL and its four studied domains (physical, psychological, social, and environmental) was relatively high, with no statistically significant difference between the consultants and general practitioners. The positive total QoL in this study was significantly lower among physicians with obesity (OR = 0.55, 95%CI = 0.25–0.97), those using butter and animal fat for cooking (OR = 0.10, 95%CI = 0.02–0.81), and those eating meals out > 3 times per week (OR = 0.30, 95%CI = 0.10–0.90). Although non-significant, vegetable consumption and a high level of physical activity were associated with a positive QoL, with adjusted ORs of 2.5 (95%CI = 0.82–7.58) and 1.5 (95%CI = 0.33–6.65), respectively.ConclusionThe findings indicate a relatively good QoL among the participating physicians; however, a lower QoL was associated with unhealthy lifestyle factors. QoL was significantly associated with obesity, cooking practices, and eating meals from restaurants.  相似文献   
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