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641.
Due to extremely high rates of evaporation and low precipitation in the Persian Gulf, discharges from desalination plants (DPs) can lead to ecological stresses by increasing water temperatures, salinities, and heavy metal concentrations, as well as decreasing dissolved oxygen levels. We discuss the potential ecological impacts of DPs on marine organisms and propose mitigating measures to reduce the problems induced by DPs discharges. The daily capacity of DPs in the Persian Gulf exceeds 11 million m3 per day, which is approximately half of global daily freshwater production; multistage flash distillation (MSF) is the dominant desalination process. Results from field and laboratory studies indicate that there are potentially serious and chronic threats to marine communities following exposure to DP discharges, especially within the zoobenthos, echinodermata, seagrasses, and coral reefs. DP discharges can lead to decreases in sensitive species, plankton abundance, hard substrate epifauna, and growth rates of seagrasses. However, the broad applicability of any one of these impacts is currently hard to scale because of the limited number of studies that have been conducted to assess the ecological impacts of DP discharge on Persian Gulf organisms. Even so, available data suggest that appropriately sited, designed, and operated DPs combined with current developments in impingement and entrainment reduction technology can mitigate many of the negative environmental impacts of DPs.  相似文献   
642.
Aberrant microRNA (miR) expression is implicated in multiple human malignancies. miR-21, acting as a proto-oncogene, is involved in a variety of cellular processes and tumorigenesis and is frequently overexpressed in some cancer types. Several tumor suppressors, metastatic, and apoptotic genes have been identified as miR-21 targets, including Ras homolog gene family member B, PTEN, Sprouty2, programmed cell death 4, Integrin-β4, and E-cadherin thereby regulating tumor growth, invasion, and metastasis. There is a growing evidence that miR-21 expression is associated with clinical outcomes in patients with colorectal cancer (CRC). In this review, we summarize the potential diagnostic, prognostic, and therapeutic values of miR-21 in CRC progression for a better understanding and hence a better management of this disease.  相似文献   
643.
By combining a Fabry–Perot (FP) cavity with a slot cavity, a compact filter structure is proposed. The peak resonance wavelength is determined by applying the FP resonance condition of the FP cavity. The relationship between filtering wavelength and cavity parameters is investigated. The results show that the filtering wavelength can be manipulated by changing the nanocavities' parameters. By using the finite difference time domain method, the theoretical predictions are confirmed. An intersection structure for nanoplasmonic waveguides is proposed and designed by utilizing two perpendicular filters. In addition to having compact dimensions, the proposed arrangement provides higher throughput and low cross talk. The proposed structure can be useful for designing compact integrated nanoplasmonic circuits.  相似文献   
644.
Venous thromboembolism (VTE) is one of the major complications in most cancer patients leading to poor prognosis and short survival. Several common clinical risk factors coexist in cancer patients are used as risk predictive biomarkers to help in the management and prevention of VTE. These include cancer site and stage, chemotherapy regimen and elevated biological markers. However, Genetic polymorphisms in genes controlling coagulation and fibrinolysis are significantly associated with VTE if detected, then they might be more sensitive individual predictive biomarkers for VTE risk assessment. This study was conducted to evaluate the association between ITGB3 rs3809865 and rs5918 with VTE risk as well as monitor the effect of VTE on overall survival of these cancer patients. In this retrospective case-control study, 195 cancer patients’ formalin-fixed paraffin embedded tissue (FFPE) samples were collected (controls n = 157, case n = 38) using the stored data through Jan 2010 to Sep 2018 from King Fahad Specialist Hospital in Dammam. Samples were genotyped using TaqMan genotyping assay, then logistic regression analysis and Chi-square were used to predict the association between risk factors and VTE. Survival Comparison was tested by the log-rank test. Genetic polymorphisms in ITGB3 (rs3809865 and rs5918) found not to be associated with VTE increasing risk in cancer patients (p>0.05). While the advanced stage was potentially increasing the risk of VTE events (OR 5.1 CI 2.01–12.9p = 0.001). Patients with VTE showed a poor overall survival reflected by the median survival rate of only three years compared to seven years for cancer patients without VTE. This study highlighted the potential influence of VTE on prognosis and survival of cancer patients and raised the importance of exploring risk predictive biomarkers in our population. This will improve the risk prediction biomarkers leading to implementing safe and effective thrombosis prophylaxis strategies.  相似文献   
645.
We analysed the polymorphisms at rs78202224 (C/A) for HSF1 gene, rs139496713 (C/T) and rs45504694 (C/A) for HSF2 gene and rs116868327 (G/A) for UBE2I gene in 547 infertile cases (non-obstructive azoospermia = 464, asthenozoospermia = 83) and 419 proven fertile controls of similar age group and ethnicity. SNP genotyping was done using AgenaMassARRY platform (Agena Bioscience, CA). Common, heterozygous, rare genotypes and allelic frequencies were analysed using dominant, recessive and co-dominant models. Data shows no significant association between HSF1, HSF2 polymorphisms and male infertility. However, under dominant (GG vs GA+AA) and co-dominanat (GG vs GA) model, polymorphism at the rs116868327 (G/A) locus in UBE2I gene was found to be linked with asthenozoospermia in males with a significant odd-ratio of 6.91 (confidence interval at 95% was 1.52-31.46; p=0.017). Moreover, frequency of rare allele was higher (2.4%) compared to controls (0.4%). Thus, this data showed a significant risk of developing asthenozoospermic condition in males (Odds ratio= 6.75; Confidence interval at 95%= 1.50-30.49; P= 0.018]. Hence, more number of genotyping studies along with the functional assay in multiple cohorts is needed to validate potential variants associated with male infertility.  相似文献   
646.
Type 2 diabetes mellitus (T2DM) is a non-autoimmune, complex, heterogeneous and polygenic metabolic disease condition characterized by persistent elevated blood glucose levels (hyperglycemia). India as said to be the diabetic capital of the world is likely to experience the largest increase in T2DM and a greater number of diabetic individuals in the world by the year 2030. Identification of specific genetic variations in a particular ethnic group has a critical role in understanding the risk of developing T2DM in a much efficient way in future. These genetic variations include numerous types of polymorphisms among which single nucleotide polymorphisms (SNPs) is the most frequent. SNPs are basically located within the regulatory elements of several gene sequences. There are scores of genes interacting with various environmental factors affecting various pathways and sometimes even the whole signalling network that cause diseases like T2DM. This review discusses the biomarkers for early risk prediction of T2DM. Such predictions could be used in order to understand the pathogenesis of T2DM and to better diagnostics, treatment, and eventually prevention.  相似文献   
647.
Two of the most problematic orthopedic and neurosurgeon visits are associated with spine and craniofacial fractures. Therefore, more attention needs to be paid to finding a medicine to repair these fractures. Amongst the most mysterious herbs, Aloe vera stands out. In the present study, the ameliorating function of A. vera on osteogenesis was studied in vitro and in vivo. Osteoblast-like cells were exposed to A. vera, followed by analysis of cell viability, lactate dehydrogenase release, and intracellular reactive oxygen species (ROS) production. The results showed an enhanced cell biocompatibility in a dose-dependent manner due to attenuated intracellular ROS production. Furthermore, a docking study indicated that the strong affinity of A. vera constituents to type I bone morphogenic protein receptor (BMPR1A) without the involvement of the BMPR1A chain B. The induction of osteogenesis prompts extracellular calcium deposition by osteoblasts, which affirms successful in vitro bone regeneration. However, injection of A. vera in rats with critical size calvarial defects induced Runx2, alkaline phosphatase (ALP), OCN, and BMP2 genes overexpression, which led to the formation of victorious bone with enhanced bone density and ALP activity. It is worthy to note that Aloin has the highest affinity to BMPR1A, whereas there are no reports regarding the impact of Aloenin, Aloesin, and γ-sitosterol on osteogenesis. Furthermore, some of them have antitumor potency, and it might be proposed that they are considered as a bone substitute in the osteotomy site of osteosarcoma with the aim of bone recovery and suppression of osteosarcoma. The whole consequences of this investigation manifests the plausibility of using A. vera as an antioxidant and osteoconductive substitute.  相似文献   
648.
The function of fibroblast cells in wounded areas results in reconstruction of the extra cellular matrix and consequently resolution of granulation tissue. It is suggested that the use of platelet-rich plasma can accelerate the healing process in nonhealing or slow-healing wounds. In this study, a simple and novel method has been used to fabricate an electrospun three-layered scaffold containing plasma rich in growth factor with the aim of increasing the proliferation and migration of fibroblast cells in vitro. First, plasma rich in growth factor was derived from platelet rich plasma, and then a three-layered scaffold was fabricated using PLLA nanofibers as the outer layers and plasma rich in growth factor-containing gelatin fibers as the internal layer. The growth morphology of cells seeded on this scaffold was compared to those seeded on one layered PLLA scaffold. The study of the cell growth rate on different substrates and the migration of cells in response to the drug release of multilayered scaffold was investigated by the cell quantification assay and a modified under agarose assay. Scanning electron microscopy and fluorescence images showed that cells seeded on multilayered scaffold were completely oriented 72 hours after seeding compared to those seeded on PLLA scaffold. The cell quantification assay also indicated significant increase in proliferation rate of cells seeded on three-layered scaffold compared to those seeded on PLLA scaffold and finally, monitoring cell migration proved that cells migrate significantly toward the three-layered scaffold up to 48 to 72 hours and afterwards start to show a diminished migration rate toward this scaffold.  相似文献   
649.
Rapid industrialization in the Kingdom of Saudi Arabia particularly in the Eastern Province is a major step towards diversification of the national income, being the second after oil sales. This study aims at estimating the degree of air pollution likely to arise from the petrochemical industry in the Jubail Industrial area, Eastern Province. The World Health Organization's (WHO 1982) recommended methodology for rapid assessment of sources of air, water and land pollution was used. Air pollution load from some industries was taken as an example. The potential air pollutants are too many to be enumerated. However, the main ones are chlorine, ammonia, and carbon monoxide. Pollutants from the industry in the region may have serious effects on the population living in that area. It is strongly recommended that the concerned authorities in the Kingdom implement an environmental control programme at this early stage before the industrial area is fully operational.  相似文献   
650.
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