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1.
Varicose veins are the most common vascular disease in humans. Veins have valves that help the blood return gradually to the heart without leaking blood. When these valves become weak, blood and fluid collect and pool by pressing against the walls of the veins, causing varicose veins. In the cardiovascular system, mechanical forces are important determinants of vascular homeostasis and pathological processes. Blood vessels are constantly exposed to a variety of hemodynamic forces, including shear stress and environmental strains caused by the blood flow. In varicose veins within the leg, venous blood pressure rises in the vein of the lower extremities due to prolonged standing, creating a peripheral tension in the vessel wall thereby causing mechanical stimulation of endothelial cells and vascular smooth muscle. Studies have shown that long-term increased exposure to vascular wall tension is associated with the overexpression of HIF-1α and HIF-2α and increased levels of MMP-2 and MMP-9, thereby reducing venous contraction and progressive venous dilatation, which is involved in the development of varicose veins. Following the expression of metalloproteinase, the expression of type 1 collagen increases, and the amount of type 3 collagen decreases. Therefore, collagen imbalance will cause the varicose veins to not stretch. Loss of structural proteins (type 3 collagen and elastin) in the vessel wall causes the loss of the biophysical properties of the varicose vein wall. This review article tries to elaborate on the effect of mechanical forces and sensors of these forces on the vascular wall in creating the mechanism of mechanosignaling, as well as the role of the onset of molecular signaling cascades in the pathology of varicose veins.  相似文献   
2.
Different morphologies of Mucor hiemalis were induced and used for the production of ethanol and biomass from rice straw through a separate hydrolysis and fermentation process. The yield of enzymatic hydrolysis was improved from 40.4% for the untreated straw to 80–93% by employing sodium hydroxide and concentrated phosphoric acid pretreatments with or without ultrasonication. The best hydrolysis performance was achieved after pretreatment by sodium hydroxide assisted with ultrasonication. The ethanol yields from the hydrolysates were 0.39–0.44 g/g depending on the pretreatment method and the fungus morphology. The yeast‐like form of the fungus showed faster glucose assimilation and slightly higher ethanol yield compared to the other morphologies. The biomass yield of mostly yeast‐like cells was more than the other morphologies (0.202–0.282 g/g glucose). Moreover, the biomass of the yeast‐like cells had more protein content (46.7–52.4 %) compared to filamentous cells (37.7–46.3 %). The cell wall, alkali‐insoluble material (AIM) of the biomass, represented 16.3–20.1% of the biomass. On average, total chitin‐chitosan content of AIM of the biomass of purely filamentous, mostly filamentous, mostly yeast‐like, and purely yeast‐like forms of the fungus was 0.460, 0.373, 0.330, and 0.336 g/g AIM of the biomass, respectively.  相似文献   
3.
The Iranian species in the Chrysis pulchella and C. varidens species groups are investigated. Six species are recognized, two of which are described for the first time: Chrysis gamberoonensis Farhad, Rosa and Talebi sp. nov. and Chrysis brunneamarginata Farhad, Rosa and Talebi sp. nov.. Chrysis gamberoonensis Farhad, Rosa and Talebi sp. nov. belongs to the C. pulchella group and is recognizable within this species group by its unique blue body coloration, scattered mesosoma punctures, polished pit row with elongated pits, and a small median tooth on the lateral edge of metasomal tergum 3. Chrysis brunneamarginata Farhad, Rosa and Talebi sp. nov. belongs to the C. varidens group and is recognizable by the usually colorless apical rim of metasomal tergum 3, and the unique shape of the anterior corners of the scutellum which are enlarged, thickened and directed backward covering the axillary trough. Dichotomous keys and distributional data for Iranian species included in these species groups are provided. Chrysis schwarzi Linsenmaier, 1968 is raised to species rank. The number of Iranian Chrysis species and subspecies is raised to 122.www.zoobank.org/urn:lsid:zoobank.org:pub:F419F860-3B90-4679-9A19-2CF5C255AE6B  相似文献   
4.
Asthma and allergic diseases are inflammatory conditions developed by excessive reaction of the immune system against normally harmless environmental substances. Although acute inflammation is necessary to eradicate the damaging agents, shifting to chronic inflammation can be potentially detrimental. Essential fatty-acids-derived immunoresolvents, namely, lipoxins, resolvins, protectins, and maresins, are anti-inflammatory compounds that are believed to have protective and beneficial effects in inflammatory disorders, including asthma and allergies. Accordingly, impaired biosynthesis and defective production of immunoresolvents could be involved in the development of chronic inflammation. In this review, recent evidence on the anti-inflam]matory effects of immunoresolvents, their enzymatic biosynthesis routes, as well as their receptors are discussed.  相似文献   
5.

Background

Screening for type 2 diabetes (T2DM) and individuals at risk of diabetes has been advocated, yet information on the response rate and diagnostic yield of different screening strategies are lacking.

Methods

Studies (from 1998 to March/2015) were identified through Medline, Embase and the Cochrane library and included if they used oral glucose tolerance test (OGTT) and WHO-1998 diagnostic criteria for screening in a community setting. Studies were one-step strategy if participants were invited directly for OGTT and two, three/four step if participants were screened at one or more levels prior to invitation to OGTT. The response rate and diagnostic yield were pooled using Bayesian random-effect meta-analyses.

Findings

47 studies (422754 participants); 29 one-step, 11 two-step and seven three/four-step were identified. Pooled response rate (95% Credible Interval) for invitation to OGTT was 65.5% (53.7, 75.6), 63.1% (44.0, 76.8), and 85.4% (76.4, 93.3) in one, two and three/four-step studies respectively. T2DM yield was 6.6% (5.3, 7.8), 13.1% (4.3, 30.9) and 27.9% (8.6, 66.3) for one, two and three/four-step strategies respectively. The number needed to invite to the OGTT to detect one case of T2DM was 15, 7.6 and 3.6 in one, two, and three/four-step strategies. In two step strategies, there was no difference between the response or yield rates whether the first step was blood test or risk-score. There was evidence of substantial heterogeneity in rates across study populations but this was not explained by the method of invitation, study location (rural versus urban) and developmental index of the country in which the study was performed.

Conclusions

Irrespective of the invitation method, developmental status of the countries and or rural/urban location, using a multi-step strategy increases the initial response rate to the invitation to screening for diabetes and reduces the number needed to have the final diagnostic test (OGTT in this study) for a definite diagnosis.  相似文献   
6.
7.
Sortases of Gram-positive bacteria catalyze the covalent C-terminal anchoring of proteins to the cell wall. Bacillus subtilis, a well-known host organism for protein production, contains two putative sortases named YhcS and YwpE. The present studies were aimed at investigating the possible sortase function of these proteins in B. subtilis. Proteomics analyses revealed that sortase-mutant cells released elevated levels of the putative sortase substrate YfkN into the culture medium upon phosphate starvation. The results indicate that YfkN required sortase activity of YhcS for retention in the cell wall. To analyze sortase function in more detail, we focused attention on the potential sortase substrate YhcR, which is co-expressed with the sortase YhcS. Our results showed that the sortase recognition and cell-wall-anchoring motif of YhcR is functional when fused to the Bacillus pumilus chitinase ChiS, a readily detectable reporter protein that is normally secreted. The ChiS fusion protein is displayed at the cell wall surface when YhcS is co-expressed. In the absence of YhcS, or when no cell-wall-anchoring motif is fused to ChiS, the ChiS accumulates predominately in the culture medium. Taken together, these novel findings show that B. subtilis has a functional sortase for anchoring proteins to the cell wall.  相似文献   
8.
Carbacylamidophosphates with the general formula RC(O)NHP(O)R1R2 constitute organophosphorus compounds that are used as insecticides, pesticides and ureas inhibitors. In this work, we studied the inhibition potency of CCl3-C(O)NHP(O)Cl21, CHCl2C(O)NHP(O)Cl(2)2, CH2ClC(O)NHP(O)Cl23 and CF3C(O)NHP(O)Cl(2)4, which are the major intermediates for carbacylamidophosphates synthesis towards human erythrocyte acetylcholinesterase (hAChe) activity using Ellman's modified kinetic method. Unexpectedly, it was observed that they were not only hydrolytically unstable but also inhibited hAChE in a similar manner to that produced by organophosphorus insecticides. Enzymatic data, bimolecular inhibition rate constants (ki) and IC50 values for inhibition of hAChE demonstrated that they are irreversible inhibitors and the inhibition potency of compound 2 (IC50 = 88 microM) was the greatest in comparison with compounds 1, 3 and 4. Also the electropositivity of the phosphorus atom and the hydrophobicity of the compounds demonstrated that these two factors play an additional effect and different role in the inhibitory activity of these compounds. Hydrolytic stability of the compounds was determined by 31P NMR monitoring of the loss of the parent molecules with D2O as a function of time. This study considers antiacetylcholinesterase activity according to the structural and the electronic aspects of compounds 1-4, according to IR, 1H, 13C and 31P NMR spectral data.  相似文献   
9.
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   
10.
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