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1.
Coronavirus (CoV) infections are commonly associated with respiratory and enteric disease in humans and animals. In 2012, a new human disease called Middle East respiratory syndrome (MERS) emerged in the Middle East. MERS was caused by a virus that was originally called human coronavirus-Erasmus Medical Center/2012 but was later renamed as Middle East respiratory syndrome coronavirus (MERS-CoV). MERS-CoV causes high fever, cough, acute respiratory tract infection, and multiorgan dysfunction that may eventually lead to the death of the infected individuals. The exact origin of MERS-CoV remains unknown, but the transmission pattern and evidence from virological studies suggest that dromedary camels are the major reservoir host, from which human infections may sporadically occur through the zoonotic transmission. Human to human transmission also occurs in healthcare facilities and communities. Recent studies on Middle Eastern respiratory continue to highlight the need for further understanding the virus-host interactions that govern disease severity and infection outcome. In this review, we have highlighted the major mechanisms of immune evasion strategies of MERS-CoV. We have demonstrated that M, 4a, 4b proteins and Plppro of MERS-CoV inhibit the type I interferon (IFN) and nuclear factor-κB signaling pathways and therefore facilitate innate immune evasion. In addition, nonstructural protein 4a (NSP4a), NSP4b, and NSP15 inhibit double-stranded RNA sensors. Therefore, the mentioned proteins limit early induction of IFN and cause rapid apoptosis of macrophages. MERS-CoV strongly inhibits the activation of T cells with downregulation of antigen presentation. In addition, uncontrolled secretion of interferon ɣ-induced protein 10 and monocyte chemoattractant protein-1 can suppress proliferation of human myeloid progenitor cells.  相似文献   
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Anionic peroxidase isoenzymes, separated on acrylamide gels, were examined in two flax genotrophs and in their reciprocal F2 hybrids. Isoenzyme 1 exhibited a significant difference in Rm between stem base and apex and there was a gradient of decreasing Rm and activity between base and apex. Isoenzyme 2 displayed only the activity gradient. The parents differed significantly in the Rm's and activities of isoenzymes 1 and 2, and the F2's showed complete dominance of the L parent for Rm, with activities being approximately intermediate.  相似文献   
4.
Abstract

Several factors may affect erythropoietin (EPO) sugar structures including designing cell culture procedure, pH, concentration of additives, dissolved oxygen, and other physicochemical parameters. In this study, we investigated the influence of changes in effective parameters and compounds on the growth rate of Chinese hamster ovary cell (CHO) cells producing recombinant EPO. Cell culture was performed at different temperature, buffering conditions, and varied concentrations of additives such as pyruvic acid, insulin, GlutaMAX, and sodium butyrate. Results indicated that the optimal temperature and pH were 37?°C and 7.2, respectively. Also, optimal concentrations for pyruvic acid, butyrate, glutamate, and insulin were obtained to be 20?mM, 1?mM, 2?mM, and 40?μg/mL, respectively. Then, cell culture was performed in microcarrier-coated spinner flasks under the optimized condition. The results showed recombinant human EPO (rhEPO) production with adequate purity. Optimization of physicochemical conditions and culture media are important factors to improve the quantity and quality of protein products. This study showed that cell growth and recombinant EPO protein production significantly increased under the optimized conditions. The results of this research can also be used in scale-up to increase the efficiency of EPO production.

Abbreviations: EPO: erythropoietin; CHO cell: Chinese hamster ovary cell; rhEPO: recombinant human EPO; DMEM: modified eagle’s medium; FBS: fetal bovine serum; SDS-PAGE: sodium dodecyl sulfate–polyacrylamide gel electrophoresis; IGF-1: insulin-like growth factor 1  相似文献   
5.
Coral Reefs - Shallow water tropical reefs are widely threatened by anthropogenic ocean warming which sometimes exceeds their thermal tolerance limit. The majority of reefs have been currently...  相似文献   
6.
International Journal of Peptide Research and Therapeutics - Cervical cancer is the second most common leading cause of women's death due to cancer worldwide, about 528,000 patients’...  相似文献   
7.

Infrastructure as a Service (IaaS) is a cloud computing service provided over the internet to facilitate the provisioning of various services such as storage, processes, etc. The provider in the IaaS market may offer some purchasing plans including: reservation, on-demand, and spot plans for its resources. As in real scenarios, demand volume for each plan is assumed to be a random variable with a given probability distribution. The provider maximizes its average revenue in the long run by optimal allocation of its resources among the plans. We formulate an Integer Linear Programming (ILP) model with a stochastic constraint, to determine the number of resources to be allocated for each plan in every time slot in the planning horizon. First, fixed prices are considered for each plan, then two mechanisms of Continuous Double Auction and Second Price Sealed Bid Auction are considered for reservations and spot plans, respectively, to obtain market-driven prices of the services. The Seasonal Weighted Moving Average method is used to predict the amount of demand in every slot. Finally, the proposed mechanisms are evaluated through simulations and the results confirm the effectiveness of the methods in maximizing the revenue and overall utilization of the available IaaS capacity.

  相似文献   
8.
Hepatitis C is a liver disease caused by the hepatitis C virus (HCV). The treatment of HCV infection has become more complicated due to various genotypes and subtypes of HCV. The treatment of HCV has made significant advances with direct-acting antivirals. However, for the choice of medicine or the combination of drugs for hepatitis C, it is imperative to detect and discriminate the crucial HCV genotypes. The main objective of this study was to determine the pattern of circulating HCV genotypes in southern Iran, from 2016 until 2019. The other aim of the study was to determine possible associations of patients’ risk factors with HCV genotypes. A total of 803 serum samples were collected in 4 years (2016–2019) from patients with HCV antibody positive results. A total of 728 serum samples were HCV-RNA positive. The prevalence of HCV genotypes was detected using the genotype-specific RT-PCR test for serum samples obtained from 615 patients. The HCV genotype 1 (G1) was the most prevalent (48.8%) genotype in the area, with G1a, G1b, and mixed G1a/b representing 38.4%, 10.1%, and 0.3%, respectively. Genotype 3a was the next most prevalent (47.2%). Mixed genotypes 1a/3a were detected in 22 (3.6%) and finally G4 was found in 3 (0.5%) patients. The other HCV genotypes were not detected in any patient. Genotype 1 (1a and 1b alone, 1a/1b and 1a/3a coinfections) is the most prevalent HCV genotype in southern Iran. HCV G1 shows a significantly higher rate in people under 40 years old.  相似文献   
9.
The current study aimed at evaluating the possibility of native Bacillus pumilus species to control Fusarium wilt in tomato and examine its effect on plant growth. Biocontrol traits of B. pumilus strains, biofilm assay, root colonisation and in vivo studies under pot conditions were determined. Strain ToIrMA-KC806242 formed biofilm efficiently and could colonise and survive on tomato rhizosphere (3.1 × 104 CFU/g of root). The amount of auxin production was recorded 29.7 μg/ml at the 96th hour of incubation. Siderophore production was determined positive, while ToIrMA was not able to solubilise phosphate compounds or produce cyanide hydrogen. Statistical analysis of data revealed that the increase in root and shoot length was recorded 60 and 84%, respectively, over control. In addition, about 73% reduction in disease incidence was determined in vivo experiments. In conclusion, this study suggests B. pumilus ToIrMA strain as a possible biocontrol agent in the field experiments.  相似文献   
10.

Aim

To assess the knowledge, attitudes, and perceptions of Saudis towards participating in clinical trials (CTs).

Methods

A cross-sectional study was conducted on 232 Saudi adult patients and their companions visiting adult outpatient clinics at King Fahad Medical City, Riyadh, Saudi Arabia. Data were collected using a self-administered questionnaire based on information obtained from the literature. The questionnaire was divided into four sections, one covering the respondents’ demographics, and the other three assessing knowledge, attitudes, and perceptions towards participating in CTs.

Results

A total of 148 (63.8%) respondents were males, and 52 (22.4%) participants had been invited to participate in a CT previously. Of those, 39 (75%) participated. Knowledge about the essential elements of informed consent ranged from 55.7% (number of participants needed) to 85.7% (confidentiality of personal information). The majority (163, 73.8%) of respondents was willing to participate in a CT after consulting their family physician and 130 (58.0%) respondents would be motivated to participate in a CT if they were healthy. Only 36.8% of the respondents believed that patients who participated in a CT received the best care. Moreover, 110 (48.7%) respondents believed that research was conducted in a responsible and ethical manner.

Conclusions

The present study assessed the current understanding of CTs among Saudi participants. Although the majority of participants had an acceptable level of knowledge about CTs, they exhibited conditional attitudes and misperceptions towards participating in a CT. Increased patient awareness may improve patients’ attitudes towards ethical conduct of CTs.  相似文献   
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