尿液中利尿剂、丙磺舒、咖啡因、匹莫林的固相提取和HPLC初筛分析

A solid-phase extraction and reversed phase high performance liquidchromatographic method(RP-HPLC) was developed for the rapid determination of 13 diuretics (bel-onging to five different pharmacological groups) ,probenecid, caffeine and pemoline in urine. Two mlurine sample was first adsorbed on a XAD-2 column, then eluted with ether--ethyl acetate(l: 1).The eluate was evaporated to dryness and reconstituted in methanol. The methanolic solution wasinjected into a HP LiChrosorb RP-18 column, using phosphate buffer (pH 3) and acetonitrile as the mo-bile phase and monitored at 216 nm, 230 nm, and 275 nm on a diode array ultraviolet detector. Theextraction recoveries of 16 drugs were above 75%. The limits of detection ranged from 0. 3～3.0μg/ml of urine. All drugs were separately administered to healthy volunteers, positive urine sampleswere collected, and urinary excretion--time curves of some drugs were reported.     

Transepithelial corneal collagen cross‐linking by iontophoresis of riboflavin

Purpose: To evaluate the effectiveness of transepithelial cornea impregnation with riboflavin 0.1% by iontophoresis for collagen cross‐linking. Material and methods:  Transepithelial collagen cross‐linking by iontophoresis of riboflavin was performed in a series of 22 eyes of 19 patients with progressive keratoconus I–II of Amsler classification. The riboflavin solution was administered by iontophoresis for 10 min in total, after which standard surface UVA irradiation (370 nm, 3 mW/cm²) was performed at a 5‐cm distance for 30 min. Results:  The riboflavin/UVA treatment resulted in a decrease in the average keratometry level from 46.47 ± 1.03 to 44.12 ± 1.12 D 1 year after the procedure. Corneal astigmatism decreased from 3.44 ± 0.48 to 2.95 ± 0.23 D. Uncorrected distance visual acuity improved from 0.61 ± 0.44 up to 0.48 ± 0.41 (LogMAR). Preoperative and postoperative endothelial cell density remained unchanged at 2765 ± 21.15 cells/mm². Conclusion:  Transepithelial collagen cross‐linking by iontophoresis might become an effective method for riboflavin impregnation of the corneal stroma reducing the duration of the procedure and being more comfortable for the patients. Further long‐term studies are necessary to complete the evaluation of the efficacy and risk spectrum of the modified cross‐linking technique.     

Traumatic alterations in GABA signaling disrupt hippocampal network activity in the developing brain

Severe head trauma causes widespread neuronal shear injuries and acute seizures. Shearing of neural processes might contribute to seizures by disrupting the transmembrane ion gradients that subserve normal synaptic signaling. To test this possibility, we investigated changes in intracellular chloride concentration ([Cl(-)](i)) associated with the widespread neural shear injury induced during preparation of acute brain slices. In hippocampal slices and intact hippocampal preparations from immature CLM-1 mice, increases in [Cl(-)](i) correlated with disruption of neural processes and biomarkers of cell injury. Traumatized neurons with higher [Cl(-)](i) demonstrated excitatory GABA signaling, remained synaptically active, and facilitated network activity as assayed by the frequency of extracellular action potentials and spontaneous network-driven oscillations. These data support a more inhibitory role for GABA in the unperturbed immature brain, demonstrate the utility of the acute brain slice preparation for the study of the consequences of trauma, and provide potential mechanisms for both GABA-mediated excitatory network events in the slice preparation and early post-traumatic seizures.     

盐城市2009-2018年居民全死因死亡与减寿分析

目的 分析2009-2018年10年期间盐城市居民死因及其对寿命的影响等,为制定疾病预防控制措施提供依据。方法 分析2009-2018年盐城市居民死亡资料,计算粗死亡率、标化死亡率、去死因期望寿命和潜在寿命损失年指标。结果 2009-2018年10年盐城市居民平均粗死亡率、标化死亡率分别为661.65/10万、359.41/10万。男女第1位死因为恶性肿瘤（262.91/10万、162.74/10万）、第2位为脑血管病（135.78/10万、148.50/10万）、第3位为呼吸系统疾病（103.68/10万、99.27/10万）、第4位为心脏病（76.52/10万、86.60/10万）、第5位为损伤和中毒（67.80/10万、38.81/10万）。对期望寿命影响最大的是恶性肿瘤和脑血管疾病,去除后寿命分别增加了3.94岁、2.97岁。结论 恶性肿瘤、脑血管疾病、呼吸系统疾病、心脏病、损伤和中毒等慢性疾病是影响健康导致死亡的主要因素。慢性病的预防控制和管理是将来疾控工作的重点,提示要加强慢性病的危险因素调查研究,大力开展健康教育和健康促进工作,从而提高居民的期望寿命和健康水平。     

Low-cost silica xerogels as potential adsorbents for ciprofloxacin removal

Ciprofloxacin, a second generation fluoroquinolone antibiotic, is one of the top pharmaceutical contaminants in water and many approaches have been developed for the removal of ciprofloxacin in wastewater. In this study, ciprofloxacin adsorption is carried out using a low-cost silica xerogel synthesized by a simple sol-gel method. The effect of pH, contact time, initial concentration of ciprofloxacin and temperature on the adsorption of ciprofloxacin by the silica xerogel is investigated. At optimum adsorption conditions, the experimental data fits well to a Langmuir isotherm and a pseudo-second-order kinetic model. The maximum ciprofloxacin adsorption capacity is determined as 24.45 mg g^?1. Thermodynamic parameters show that ciprofloxacin adsorption by the silica xerogel is a spontaneous endothermic process. Moreover, reusability experiments reveal that the silica xerogel can be effectively used several times for ciprofloxacin adsorption. The promising results indicate that the silica xerogel can be regarded as potential adsorbent for ciprofloxacin removal.     

Childhood asthma and vitamin D deficiency in Turkey: is there cause and effect relationship between them?

Background

Epidemiological studies show that vitamin D deficiency and insufficiency are common worldwide and associated with many diseases including asthma. Our aim was to evaluate vitamin D insufficiency and its clinical consequences.

Methods

This cross-sectional study was carried out on 170 children consisted of 85 who were asthmatic and 85 who were not, aged 2 to 14 years in Tekirdag, Turkey, from September 2009 to May 2010. Children’s basal serum D vitamin levels were determined, and their eating habits, vitamin D intake, exposure to sunlight and use of health services during the previous year were investigated. The severity of asthma and levels of asthma control were assessed according to the Global Initiative for Asthma guidelines.

Results

The difference between mean vitamin D levels in the asthmatic group (mean +/- SD) 16.6 +/- 8.5 ng/mL and the healthy control group (mean +/- SD) 28.2 +/- 19.5 ng/mL was found to be statistically significant (p?<?0.001). Children in the asthma group had less exposure to sunlight and ate a diet less rich in vitamin D (p?<?0.001). A significant difference was observed between the groups regarding the frequency of respiratory tract infections leading to emergency unit admissions and number of hospitalizations (p?<?0.001). It was also shown that a decrease in vitamin D level increased the severity of asthma (p?<?0.001) and decreased the frequency of controlled asthma (p?=?0.010).

Conclusion

This study has demonstrated the correlation between plasma 25 (OH) D levels and childhood asthma. Evidently, this relationship being influenced by multiple factors other than vitamin D, further studies should be conducted to explore the interrelation between all such factors.

     

Hydrogen sulfide increases calcium-activated potassium (BK) channel activity of rat pituitary tumor cells

Hydrogen sulfide (H₂S) is the third gasotransmitter found to be produced endogenously in living cells to exert physiological functions. Large conductance (maxi) calcium-activated potassium channels (BK), which play an important role in the regulation of electrical activity in many cells, are targets of gasotransmitters. We examined the modulating action of H₂S on BK channels from rat GH₃ pituitary tumor cells using patch clamp techniques. Application of sodium hydrogen sulfide as H₂S donor to the bath solution in whole cell experiments caused an increase of calcium-activated potassium outward currents. In single channel recordings, H₂S increased BK channel activity in a concentration-dependent manner. Hydrogen sulfide induced a reversible increase in channel open probability in a voltage-dependent, but calcium independent manner. The reducing agent, dithiothreitol, prevented the increase of open probability by H₂S, whereas, the oxidizing agent thimerosal increased channel open probability in the presence of H₂S. Our data show that H₂S augments BK channel activity, and this effect can be linked to its reducing action on sulfhydryl groups of the channel protein.