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1.
Protoplasma - Watermelon and melon are members of the Cucurbitaceae family including economically significant crops in the world. The expansin protein family, which is one of the members of the...  相似文献   
2.
In this work, the synthesis, characterization, and biological activities of a new series of 1,3,4-thiadiazole derivatives were investigated. The structures of final compounds were identified using 1H-NMR, 13C-NMR, elemental analysis, and HRMS. All the new synthesized compounds were then screened for their antimicrobial activity against four types of pathogenic bacteria and one fungal strain, by application of the MIC assays, using Ampicilin, Gentamycin, Vancomycin, and Fluconazole as standards. Among the compounds, the MIC values of 4 and 8 μg/mL of the compounds 3f and 3g , respectively, are remarkable and indicate that these compounds are good candidates for antifungal activity. The docking experiments were used to identify the binding forms of produced ligands with sterol 14-demethylase to acquire insight into relevant proteins. The MD performed about 100 ns simulations to validate selected compounds’ theoretical studies. Finally, using density functional theory (DFT) to predict reactivity, the chemical characteristics and quantum factors of synthesized compounds were computed. These results were then correlated with the experimental data. Furthermore, computational estimation was performed to predict the ADME properties of the most active compound 3f .  相似文献   
3.
We investigated programmed cell death 1 (PD-1) / programmed cell death ligand 1 (PD-L1) expression in high grade serous ovarian cancer (HGSOC) and its relationship to tumor infiltrating lymphocytes (TIL) and prognosis. Formalin fixed paraffin embedded (FFPE) samples of 94 HGSOC cases were included in the study. Immunohistochemical analysis (CD3, CD4, CD8, PD-1 and PD-L1) was performed. Samples were analyzed for expression of immune proteins in the peritumoral stromal and intratumoral areas, scored, and expression was correlated with overall survival, stage, and age. PD-L1 staining ratio with a score greater than 0 was found to have lower survival. There were two positive staining patterns, patchy/diffuse and patchy/focal patterns, in 24 (25.5%) cases. Considering the threshold value ≥5%, we demonstrated that the PD-L1 positive cancer cell membrane immunoreactivity rate and patchy/diffuse PD-L1 expression were 9.6% (n = 9). There was statistically significant relationship between high PD-1 scores and PD-L1 cases of ≥ 5%. A statistically significant difference was found between PD-L1 staining and survival in patients with a threshold ≥ 5%. However an appropriate rate for treatment was determined in 9.6% cases. There was a statistically significant correlation between PD-1 positive TIL score and intratumoral CD3, peritumoral stromal CD3, intratumoral CD4 and intratumoral CD8 positive cells. Survival was lower in cases with higher PD-L1 positive stromal TIL score.  相似文献   
4.
Yilmaz  Şehnaz  Yoldas  Oguz  Dumani  Aysin  Guler  Gizem  Ilgaz  Seda  Akbal  Eylül  Oksuz  Hale  Celik  Ayla  Yilmaz  Bertan 《Molecular biology reports》2020,47(7):5377-5383
Molecular Biology Reports - Antimicrobial irrigation solutions are widely used under clinical settings. Their effect on dental tissue is a subject of recent research, which aims for a safer...  相似文献   
5.
Intermittent hypoxia is the most common pattern of hypoxic exposure in humans. The effect of chronic long-term intermittent hypobaric hypoxia (CLTIHH) on bone metabolism is not investigated. We examined the effect of CLTIHH on bone metabolism and the role of nitric oxide (NO) in this process. The rats were divided into three groups in this study. The animals in groups I and II have been exposed to CLTIHH. The animals in group II were also treated with nitric oxide synthase inhibitor NG-nitro-l-arginine methyl ester. To obtain CLTIHH, rats were placed in a hypobaric chamber (430 mm Hg; 5 h/day, 5 days/week, 5 weeks). The group III (control) rats breathed room air in the same environment. At the begining of the experiments, bone mineral density (BMD) of the animals were measured, and blood samples were collected from the tail vein. After the 5-week CLTIHH period, the same measurements were repeated. Parathyroid hormone, calcium, phosphate, bone alkaline phosphatase (b-ALP), NO, interleukin 1 beta, interleukin 6, and tumor necrosis factor alpha levels were determined. The cytokines, NO levels, and BMD in CLTIHH-induced rats were higher compared with baseline and control values. The cytokines, b-ALP, and BMD increased while NO levels decreased in the group II compared with baseline values. BMD values of group II were lower than group I but higher than control group. Our results suggested that CLTIHH has positive effects on bone density. Intermittent hypoxia protocols may be developed for treatment and prevention of osteopenia and osteoporosis.  相似文献   
6.
Integrin CD11b/CD18 is a key adhesion receptor that mediates leukocyte migration and immune functions. Leukadherin-1 (LA1) is a small molecule agonist that enhances CD11b/CD18-dependent cell adhesion to its ligand ICAM-1. Here, we used single-molecule force spectroscopy to investigate the biophysical mechanism by which LA1-activated CD11b/CD18 mediates leukocyte adhesion. Between the two distinct populations of CD11b/CD18:ICAM-1 complex that participate in cell adhesion, the cytoskeleton(CSK)-anchored elastic elements and the membrane tethers, we found that LA1 enhanced binding of CD11b/CD18 on K562 cells to ICAM-1 via the formation of long membrane tethers, whereas Mn2+ additionally increased ICAM-1 binding via CSK-anchored bonds. LA1 activated wild-type and LFA1−/− neutrophils also showed longer detachment distances and time from ICAM-1-coated atomic force microscopy tips, but significantly lower detachment force, as compared to the Mn2+-activated cells, confirming that LA1 primarily increased membrane-tether bonds to enhance CD11b/CD18:ICAM-1 binding, whereas Mn2+ induced additional CSK-anchored bond formation. The results suggest that the two types of agonists differentially activate integrins and couple them to the cellular machinery, providing what we feel are new insights into signal mechanotransduction by such agents.  相似文献   
7.
A bioassay-guided phytochemical analysis of the triterpene saponins from under ground parts of Gypsophila arrostii var. nebulosa allowed the isolation of two triterpene saponins; nebuloside A, B based on gypsogenin and quillaic acid aglycone. Two new oleanane type triterpenoid saponins (nebuloside A, B) and three known saponins (13) were isolated from the root bark of Gypsophila arrostii var. nebulosa. The structures of the two new compounds were elucidated as 3-O-β-d-galactopyranosyl-(1→2)-[β-d-xylopyranosyl-(1→3)]-β-d-glucuronopyranosyl quillaic acid 28-O-β-d-glucopyranosyl-(1→3)-[β-d-xylopyranosyl-(1→3)-β-d-xylopyranosyl-(1→4)]-α-l-rhamnopyranosyl-(1→2)-β-d-fucopyranosyl ester (nebuloside A) and 3-O-β-d-xylopyranosyl-(1→3)-[β-d-galactopyranosyl(1→3)-β-d-galactopyranosyl-(1→2)]-β-d-glucuronopyranosyl gypsogenin 28-O-β-d-glucopyranosyl-(1→3)-[β-d-xylopyranosyl-(1→3)-β-d-xylopyranosyl-(1→4)]-α-l-rhamnopyranosyl-(1→2)-β-d-fucopyranosyl ester (nebuloside B), on the basis of extensive spectral analysis and chemical evidence. Nebuloside A and B showed toxicity enhancing properties on saporin a type-I RIP without causing toxicity by themselves at 15 μg/mL.  相似文献   
8.
The objective of this study was to elucidate the effect of soybean oil (SbO) and sesame oil (SO) supplemented diets on bone biomarkers changes in OVX (ovariectomized) rats. The current data exhibited significant decrease in BMD (bone mineral density), accompanied with marked depletion in the level of Ca, P and Mg in both serum and bone of OVX rats. Also, serum estrogen, total protein, HDL-C (high density lipoprotein cholesterol), bone NO levels were decreased in OVX rats. However, a significant increase in the level of serum TL (total lipids), TC (total cholesterol), TG (triglycerides), LDL-C (low density lipoprotein cholesterol), VLDL-C (very low density lipoprotein cholesterol), urine minerals (Ca, P, Mg), as well as serum, bone and urine ALP (alkaline phosphatase) and ACP (acid phosphatase) activity were recorded in OVX rats. Further changes were also detected by the increased level of urine hydroxyproline, serum parathyroid hormone and osteocalcin, as well as urea and creatinine level in both serum and urine. On the other hand, when OVX rats were fed on SbO (soy bean oil) (15 % w/w) or SO (sesame oil) (10 % w/w) supplemented diets, the data recorded a significant improvement in all the above mentioned parameters. So, it can be concluded that consumption of SbO or SO supplemented diets might be considered as a functional food for retarding risks of osteoporosis associated with estrogen deficiency in OVX states.  相似文献   
9.
10.

Background

Hospital performance is frequently evaluated by analyzing differences between hospital averages in some quality indicators. The results are often expressed as quality charts of hospital variance (e.g., league tables, funnel plots). However, those analyses seldom consider patients heterogeneity around averages, which is of fundamental relevance for a correct evaluation. Therefore, we apply an innovative methodology based on measures of components of variance and discriminatory accuracy to analyze 30-day mortality after hospital discharge with a diagnosis of Heart Failure (HF) in Sweden.

Methods

We analyzed 36,943 patients aged 45–80 treated in 565 wards at 71 hospitals during 2007–2009. We applied single and multilevel logistic regression analyses to calculate the odds ratios and the area under the receiver-operating characteristic (AUC). We evaluated general hospital and ward effects by quantifying the intra-class correlation coefficient (ICC) and the increment in the AUC obtained by adding random effects in a multilevel regression analysis (MLRA). Finally, the Odds Ratios (ORs) for specific ward and hospital characteristics were interpreted jointly with the proportional change in variance (PCV) and the proportion of ORs in the opposite direction (POOR).

Findings

Overall, the average 30-day mortality was 9%. Using only patient information on age and previous hospitalizations for different diseases we obtained an AUC = 0.727. This value was almost unchanged when adding sex, country of birth as well as hospitals and wards levels. Average mortality was higher in small wards and municipal hospitals but the POOR values were 15% and 16% respectively.

Conclusions

Swedish wards and hospitals in general performed homogeneously well, resulting in a low 30-day mortality rate after HF. In our study, knowledge on a patient’s previous hospitalizations was the best predictor of 30-day mortality, and this information did not improve by knowing the sex and country of birth of the patient or where the patient was treated.  相似文献   
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