Vascular endothelial growth factor in exercising humans under different environmental conditions

It was the aim of this study to investigate the time course of changes in the serum concentrations of vascular endothelial growth factor (VEGF) during a regular survival training programme combined with food and fluid deprivation and during a high altitude marathon run. We studied soldiers of the Austrian Special Forces performing survival training at sea-level and marathon runners of the Posta Atletica who crossed the border between Chile and Argentina at altitudes up to 4722 m. Baseline data collected before the 1-week of survival training showed that the soldiers had normal VEGF [n = 8, 246.7 (SD 118.5) pg.ml(-1)] serum concentrations which remained unchanged during the course of the study. Before the high altitude marathon the subjects showed normal VEGF serum concentrations [178 (SD 84.5) pg.ml(-1)]. After the run VEGF concentrations were found to be significantly decreased [41.0 (SD 41.6) pg ml(-1), P < 0.01]. It was concluded that prolonged physical stress during normobaric-normoxia did not alter the VEGF concentrations whereas during severe hypobaric-hypoxia decreased VEGF serum concentrations were measured, at least temporarily, after prolonged physical exercise which might have been due to changes in production, release, removal and/or binding of circulating VEGF.     

银杏叶片的光抑制和光保护机制：温度,CO2和O2的影响

田间条件下,夏季晴天中午银杏（ＧｉｎｋｇｏｂｉｌｏｂａＬ．）叶片经常遭受强光（超过１４００μｍｏｌ·ｍ－２·ｓ－１）和高温（３５℃左右）胁迫,气孔导度和ＣＯ２同化速率出现明显的“午休”现象。叶黄素循环关键组分玉米黄质在一天中随着光强而变化。在室内分析了强光和高温交互作用对银杏叶片光抑制的影响。在１５～３５℃温度范围内和１４００μｍｏｌ·ｍ－２·ｓ－１光强下,银杏叶片分别在空气中、低ＣＯ２浓度（８０μＬ·Ｌ－１）和２％Ｏ２条件下处理２ｈ。银杏叶肉ＣＯ２导度低（约３１ｍｍｏｌ·ｍ－２·ｓ－１）,导致羧化部位ＣＯ２浓度低,光呼吸较强。在空气中,电子传递与固定ＣＯ２之比较高（１６ｅ－／ＣＯ２,２５℃）。此比率在２％Ｏ２条件下仍随温度的升高而增大,仅用光呼吸的变化不能解释。在１５～３５℃温度范围内和不同ＣＯ２浓度下,降低Ｏ２虽然导致电子传递速率下降,但对光抑制程度无影响,表明强光条件下光呼吸对银杏叶片无保护作用。依赖叶黄素循环的非幅射能量耗散是银杏叶片防止强光损伤的主要机制     

Variation in archaeal and bacterial community profiles and their functional metabolic predictions under the influence of pure and mixed fertilizers in paddy soil

Impact of environmental perturbations i.e., nitrogen (N), phosphorus (P), potassium (K), and rice straw (Rs) on the dynamics of soil bacterial and archaeal communities are multifactor dependent and seeks a contemporary approach to study underlying mechanisms. The current study investigates the effect of pure and mixed fertilizers on soil physicochemical properties, the microbial community structure, and their functional metabolic predictions. It involved amendments with distinct combinations of N as C(H₂N)₂O, P and K as KH₂PO₄, K as KCl, and Rs in paddy soil microcosms with concentrations common in rice fields agriculture. Soil pH, electrical conductivity (EC), total carbon (TC), total nitrogen (TN), organic matter (OM), available K (AK), and total extractable P (TEP) were evaluated. To comprehend community variation and functional predictions, 16S rRNA-based high throughput sequencing (HTS) and phylogenetic investigation of communities by reconstruction of unobserved states (PICRUSt) were employed, respectively. Our findings showed enhanced community richness and diversity in all amendments compared to control. Proteobacteria, Actinobacteria, and Firmicutes were dominant bacterial phyla. Regarding relative abundance, Chloroflexi, Bacteroidetes, and Verrucomicrobia showed positive while Actinobacteria, Acidobacteria, and Gemmatimonadetes showed negative trends compared to controls. Thaumarchaeota and Euryarchaeota were dominant archaeal phyla and exhibited increasing and decreasing trends, respectively. The PICRUSt analysis indicated functional prediction more towards amino acid, carbohydrate, energy, and lipid metabolism while less towards others. Concerning energy metabolism, most and least responsive treatments were KP and controls, respectively. These outcomes enhanced our understanding regarding soil quality, fertilizer composition and application, and functional metabolomics of archaea and bacteria.     

Emulsification in High‐Pressure Homogenizers

High‐pressure homogenizers are frequently employed for the homogenization of low‐viscosity emulsions containing a proportion of disperse phase which is not too high. High‐pressure homogenizers essentially consist of a high‐pressure pump and a homogenizing nozzle. The design of the homogenizing nozzle influences the flow of the emulsion in the nozzle itself and hence the results of droplet disruption. It is shown which mechanism in frequently used homogenizing nozzles is usually responsible for disruption. Experimental results reveal the effects of the dispersed phase content and the viscosity of the disperse and continuous phases in different nozzles. The results can be explained on the basis of the mechanisms of disruption. Finally, the homogenizing nozzles presented are directly compared with one another.     

高迁移率族蛋白1拮抗剂BoxA对血管性痴呆大鼠急性期海马区域神经炎症的抑制作用

目的:探究高迁移率族蛋白1(HMGB1)拮抗剂BoxA脑室立体定向注射对双侧颈总动脉闭塞(2VO)后大鼠海马区域神经炎症(血脑屏障通透性、小胶质细胞的激活以及炎症因子水平等)的抑制作用。方法:60只雄性Sprague-Dawley(SD)大鼠分为假手术组(即Sham组)、PBS组以及BoxA组(各组n=20),分别在行2VO(n=40,正常手术)或假手术(n=20,仅暴露不结扎)后,立即用BoxA(10μg在10uL PBS溶液中,n=20)或者等体积PBS(n=20)立体定向注射到左侧侧脑室中。造模3 d后,用HMGB1和NeuN免疫荧光双染,western blot观察HMGB1出核现象,伊文思蓝(EB)染色和脑水含量测量评价血脑屏障(BBB)通透性,Iba1免疫荧光染色观察小胶质细胞活化,定量逆转录聚合酶链反应(RT-PCR)检测炎症细胞因子(白介素1β(Interleukin-1β, IL-1β)和白介素6(In-terleukin-6, IL-6)和肿瘤坏死因子α(Tumor necrosis factor-α, TNF-α))的基因表达水平。结果:相比Sham组,PBS组海马CA1亚区HMGB1阳性细胞核(%)以及HMGB1NeuN阳性细胞/HMGB1阳性细胞(%)显著下降(P0.01),而BoxA组以上改变较PBS组部分减少(P0.05)。PBS组EB渗漏、脑含水量均较Sham组显著增加(P0.001),而BoxA组以上指标均较PBS组明显减轻(P0.05)。PBS组Iba1阳性细胞相比Sham组明显增多(P0.01),且炎症因子(IL-1β、IL-6和TNF-α)表达显著增高(P0.05);而相比PBS组,BoxA组Iba1阳性细胞表达减少((P0.05),且炎症因子(IL-1β、IL-6 and TNF-α表达明显减少(P0.05)。结论:HMGB1抑制剂BoxA立体定向注射能够有效缓解急性期血管性痴呆大鼠海马区域的神经炎症反应。     

Evaluation of healing following frenectomy

Aberrant frenum attachment would cause plaque accumulation and malalignment of teeth. It can be managed by frenotomy or frenectomy methods, through a conventional surgical technique or laser technique. Therefore, it is of interest to compare frenectomy healing surgical and laser techniques. Data from 51 outpatients and post-operative healing of frenectomy was assessed by Landry’s healing score index using 3 weeks postoperative photographs followed by statistical analysis. Based on the healing score index, the laser technique showed better outcomes than the surgical technique. Moreover, the association between the management of high frenal attachment and the healing score index was found to be statistically significant.     

Structural studies and biological evaluation of T30695 variants modified with single chiral glycerol-T reveal the importance of LEDGF/p75 for the aptamer anti-HIV-integrase activities

Some G-quadruplex (GQ) forming aptamers, such as T30695, exhibit particularly promising properties among the potential anti-HIV drugs. T30695?G-quadruplex binds to HIV-1 integrase (IN) and inhibits its activity during 3′-end processing at nanomolar concentrations. Herein we report a study concerning six T30695-GQ variants, in which the R or S chiral glycerol T, singly replaced the thymine residues at the T30695?G-quadruplex loops. CD melting, EMSA and HMRS experiments provided information about the thermal stability and the stoichiometry of T30695-GQ variants, whereas CD and ¹H NMR studies were performed to evaluate the effects of the modifications on T30695-GQ topology. Furthermore, LEDGF/p75 dependent and independent integration assays were carried out to evaluate how T loop modifications impact T30695-GQ biological activities. The obtained results showed that LEDGF/p75 adversely affects the potencies of T30695 and its variants. The IN inhibitory activities of the modified aptamers also depended on the position and on the chirality (R or S) of glycerol T loop in the GQ, mostly regardless of the G-quadruplex stabilities. In view of our and literature data, we suggest that the allosteric modulation of IN tetramer conformations by LEDGF/p75 alters the interactions between the aptamers and the enzyme. Therefore, the new T30695 variants could be suitable tools in studies aimed to clarify the HIV-1 IN tetramers allostery and its role in the integration activity.     

The use of out-of-plane high Z patient shielding for fetal dose reduction in computed tomography: Literature review and comparison with Monte-Carlo calculations of an alternative optimisation technique

When performing CT examinations on pregnant patients, great effort should be dedicated towards optimising the exposure of the mother and the conceptus. For this purpose, many radiology departments use high-Z garments to be wrapped around the patient's lower abdomen for out-of-plane organ shielding to protect the fetus. To assess their current protection efficiency, we performed a literature review and compared the efficiencies mentioned in the literature to Monte-Carlo calculations of CT protocols for which the overall scan length was reduced. We found 11 relevant articles, all of them reporting uterus exposure due to CT imaging performed for exclusion of pulmonary embolism, one of the leading causes of peripartum deaths in western countries. Uterus doses ranged between 60 and 660 µGy per examination, and relative dose reductions to the uterus due to high-Z garments were between 20 and 56%. Calculations showed that reducing the scan length by one to three centimetres could potentially reduce uterus dose up to 24% for chest imaging, and even 47% for upper abdominal imaging. These dose reductions were in the order of those achieved by high-Z garments. However, using the latter may negatively influence the diagnostic image quality and even interfere with the automatic exposure control system thus increasing patient dose if positioned in the primary beam, for example in the overranging length in helical acquisition. We conclude that efforts should be concentrated on positioning the patient correctly in the gantry and optimising protocol parameters, rather than using high-Z garments for out-of-plane uterus shielding.