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1.
Natural killer (NK) cells have significant capability in tumor immune-surveillance. The ability of lyse transformed cells immediately in an antigen-independent manner make them an attractive candidate for cancer cell therapy. Despite employment of NK cells in cancer immunotherapy, clinical trials are faced with serious limitations such as trouble with the penetration of NK cells in tumor sites, limited in vivo persistence, and tumor microenvironment interference. Taken together, the NK-cell cancer therapy is still infant scenario that has a long way to be translated in clinic. Current article first reviews characteristic features of NK lymphocytes. Then, it discusses about important disruptive barriers and motivator in the developmental stages of NK cells like as tumor microenvironment. Finally, some revolutionary approaches are highlighted utilizing of NK cells in cancer therapy.  相似文献   
2.
Dromedary camels (Camelus dromedarius) play a major economic role in many countries in Africa and Asia. Although they are resistant to harsh environmental conditions, they are susceptible to a wide range of zoonotic agents. This study aimed to provide an overview on the prevalence of selected zoonotic pathogens in blood and tissues of camels in central Iran. Blood, liver, portal lymph node, and brain were collected from 100 apparently healthy camels at a slaughterhouse in Qom city to assess the presence of DNA of Brucella spp., Trypanosoma spp., Coxiella burnetii, and Bartonella spp. PCR products were sequenced bidirectionally and phylogenetic analyses were performed. Eleven percent of camels tested positive for Brucella abortus (3%) and Trypanosoma evansi (8%). Coxiella burnetii and Bartonella spp. DNA was not detected. Our data demonstrate that camels from Iran contribute to the epidemiology of some zoonotic pathogens. Performing proper control strategies, such as vaccination of camels and humans in contact with them, test-and-slaughter policy, and education of the general population is necessary for minimizing the risk of zoonotic infection.  相似文献   
3.
Nuclear pore complex (NPC) is the only corridor for macromolecules exchange between nucleus and cytoplasm. NPC and its components, nucleoporins, play important role in the diverse physiological processes including macromolecule exchange, chromosome segregation, apoptosis and gene expression. Recent reports also suggest involvement of nucleoporins in carcinogenesis. Applying proteomics, we analyzed expression pattern of the NPC components in a newly established esophageal cancer cell line from Persia (Iran), the high-risk region for esophageal cancer. Our results indicate overexpression of Hsc70 and downregulation of subunit alpha type-3 of proteasome, calpain small subunit 1, and eIF5A-1. Among these proteins, Hsc70 and eIF5A-1 are in direct interaction with NPC and involved in the nucleocytoplasmic exchange. Hsc70 plays a critical role as a chaperone in the formation of a cargo–receptor complex in nucleocytoplasmic transport. On the other hand, it is an NPC-associated protein that binds to nucleoporins and contributes in recycling of the nucleocytoplasmic transport receptors in mammals and affects transport of proteins between nucleus and cytoplasm. The other nuclear pore interacting protein: eIF5A-1 binds to the several nucleoporins and participates in nucleocytoplasmic transport. Altered expression of Hsc70 and eIF5A-1 may cause defects in nucleocytoplasmic transport and play a role in esophageal carcinogenesis.  相似文献   
4.

Objective

To evaluate the effect of alcohol cessation on the risk of developing laryngeal and pharyngeal cancers, combining available evidence in the scientific literature in a meta-analysis.

Methods

A systematic literature review was conducted, and a meta-analysis was applied on the retrieved studies. The generalised least squares method was used to estimate the trend from dose-response data to assess changes in the risks of laryngeal and pharyngeal cancers after drinking cessation.

Results

A total of 9 case-control studies were included in the meta-analysis (4 and 8 estimates for laryngeal and pharyngeal cancers, respectively). On average, alcohol drinking cessation was associated with a 2% yearly reduction in the risk of developing laryngeal and pharyngeal cancers. There was a considerable heterogeneity between the studies of pharyngeal cancer, but this was mostly due to two studies. The increased risk of laryngeal and pharyngeal cancers caused by alcohol was reversible; the time periods until the risks became equal to those of never drinkers were 36 (95% CI 11–106) and 39 (95% CI 13–103) years, respectively. Moreover, 5 years of drinking cessation was associated with a reduction of around 15% in the alcohol-related elevated risk of laryngeal and pharyngeal cancers.

Conclusion

Although a long time period is required to completely eliminate the alcohol-related elevated risk of laryngeal and pharyngeal cancers, a substantial risk reduction can be seen in the short term (5–10 years), and drinking cessation should therefore be encouraged to reduce the incidence of these cancers.  相似文献   
5.
ProjectOmeprazole is one of the most frequently prescribed drugs in patients with gastroesophageal reflux disease (GERD). It increases the gastric pH and this in turn may change the intestinal absorption of trace elements. This study was conducted to assess the effects of omeprazole consumption on the serum level of trace elements.ProceduresThe studied subjects were selected from the list of patients referred to the gastroenterology department of 5 Azar hospital in Golestan province of Iran for whom omeprazole was prescribed by a gastroenterologist. Blood samples were obtained before (phase I) and after an eight-week period (phase II) of omeprazole consumption. Serum levels of trace elements were assessed by the photometric method.ResultsSixty seven patients were recruited of whom, 35.82% were males. There was no significant difference in serum levels of Fe, P, Ca and Cu between phases I and II. Serum concentration of Zn was significantly lower in phase II than I (P = 0.02). The proportion of male patients with low Zn levels was significantly higher in phase II (50%) than I (16.7%) (P = 0.01). We found no significant difference in the proportion of female patients with low Zn levels between phase I (37.2%) and phase II (27.9%).ConclusionsWe found no significant reduction in serum levels of Fe, P, Ca and Cu in phase II. However, our results showed that serum level of Zn was significantly lower after omeprazole consumption in males. So, nutritional supplement of Zn should be considered in male patients treated with omeprazole.  相似文献   
6.
A diffusion-based microreactor system operated with a reaction volume of 8 μL is presented and characterized to intensify the process understanding in microscale cultivations. Its potential as screening tool for biological processes is evaluated. The advantage of the designed microbioreactor is the use for the continuous cultivation mode by integrating online measurement technique for dissolved oxygen (DO) and optical density (OD). A further advantage is the broaden application for biological systems. The bioreactor geometry was chosen to achieve homogeneous flow during continuous process operation. The device consisted of a microstructured top layer made of poly(dimethylsiloxane) (PDMS), which was designed and fabricated using UV-depth and soft lithography assembled with a glass bottom. CFD simulation data used for geometry design were verified via microparticle-image-velocimetry (μPIV). In the used microreactor geometry no concentration gradients occurred along the entire reaction volume because of rapid diffusive mixing, the homogeneous medium flow inside the growth chamber of the microreactor could be realized. Undesirable bubble formation before and during operation was reduced by using degassed medium as well as moistened and moderate incident air flow above the gas permeable PDMS membrane. Because of this a passive oxygen supply of the culture medium in the device is ensured by diffusion through the PDMS membrane. The oxygen supply itself was monitored online via integrated DO sensors based on a fluorescent dye complex. An adequate overall volumetric oxygen transfer coefficient K(L)a as well as mechanical stability of the device were accomplished for a membrane thickness of 300 μm. Experimental investigations considering measurements of OD (online) and several metabolite concentrations (offline) in a modified Verduyn medium. The used model organism Saccharomyces cerevisiae DSM 2155 tended to strong reactor wall growth resembling a biofilm.  相似文献   
7.
Biogeochemistry - The biogeochemical model, PnET-BGC, was modified and parameterized using field data from an experimental whole-tree harvest of watershed (W5) in 1983–1984 at the Hubbard...  相似文献   
8.
9.
The conventional wetland system using Phragmites sp. is in existence since 20 years. The constructed wetland system has not gained much popularity due to large land area requirement, clogging of beds and need for capital investment. The aim of the study is to develop a new approach to the horizontal flow wetlands system (termed bio-rack) for treatment of domestic wastewater. The new system dealt with an engineered attached growth matrix and a high microbial degradation rate. The study on bio-rack was undertaken in a horizontal flow pilot plant using Phragmites sp. and experiments were carried out for various parameters. Analytical data were collected during the studies which include temperature, pH, chemical oxygen demand (COD), biological oxygen demand (BOD5), dissolved oxygen (DO), chlorides, total dissolved solids (TDS), total suspended solids (TSS), ammonia nitrogen (NH3-N), phosphate (PO4-P) and most probable number (MPN). This paper also studies microbial flora present in the system by isolating and identifying the microorganisms, and also measuring total viable count (TVC). Morphological aspects with reference to the growth of plant were studied and it indicated high plant yield. At optimum hydraulic retention time (HRT) of 10 h, approximately 75.15% COD, 86.59% BOD5, 27.54% TDS, 73.13% TSS, 8.86% Chlorides, 70.22% NH3-N, 31.71% PO4-P and 92.11% MPN reduction was achieved in bio-rack system. A comparative evaluation was done with the conventional wetland system and better treatment efficiency was observed in the bio-rack system. This result indicates a possibility of development of a substantially effective system compared to any other methods on constructed wetland.  相似文献   
10.
Two trials were conducted in a 2?×?2?+?1 factorial arrangement based on a completely randomized design to evaluate the effects of different sources of selenium (Se) on performance, blood metabolites, and nutrient digestibility in male lambs on a barley-based diet. The first trial lasted for 70 days and consisted of 30 lambs (35.6?±?2.6 kg mean body weight, about 4–5 months of age) which were randomly allotted to five treatments including: (1) basal diet (containing 0.06 mg Se/kg DM; control) without supplementary Se, (2) basal diet?+?0.20 mg/kg Se as sodium selenite (SeS 0.20), (3) basal diet?+?0.40 mg/kg Se as sodium selenite (SeS 0.40), (4) basal diet?+?0.20 mg/kg Se as selenium yeast (SeY 0.20), and (5) basal diet?+?0.40 mg/kg Se as selenium yeast (SeY 0.40). For the second trial, four lambs from each group of experiment 1 were randomly allocated to individual metabolic cages for 14 days to measure the effects of dietary Se on nutrient digestibility. The results revealed that there were no significant differences for average daily gain, average daily feed intake, feed/gain ratio, hematological parameters (packed cell volume, red blood cell, white blood cell, and hemoglobin values), serum total protein, albumin, globulin, aspartate amino transferase, alkaline phosphatase, and creatine phosphokinase due to supplementation of different amounts and sources of Se in lambs. Dietary Se supplementation significantly improved (P?<?0.001) glutathione peroxidase activity in blood. Furthermore, at the end of the trial, serum tri-iodothyronine (T3) amount also increased (P?<?0.05), while serum thyroxine (T4) amount decreased (P?<?0.05). Digestibility of dry matter, organic matter, crude protein, neutral detergent fiber, and acid detergent fiber increased (P?<?0.05) by Se yeast supplementation. It may be concluded that supplementation of Se in lambs had no significant effect on performance and blood hematology, but increased blood glutathione peroxidase activity and serum T3 amount and decreased serum T4 amount as compared to non-supplemented control lambs. Furthermore, Se yeast improved nutrient digestibility in lambs.  相似文献   
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