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101.
Direct alcohol biomarkers, including urinary ethyl glucuronide (EtG), urinary ethyl sulfate (EtS), and blood phosphatidylethanol (PEth), are used to monitor alcohol abstinence in individuals who are mandated to abstain. In this consecutive case series study, we examined 1000 forensic reports of participants enrolled in a professionals health program who were contractually obligated to abstain from alcohol and who underwent recovery status evaluations. We identified 52 evaluations in which urinary EtG, EtS, and blood PEth were measured and which produced a positive result for at least one of these analytes. PEth, at a cutoff concentration of 20 ng/mL, revealed alcohol use more frequently than EtG or EtS at our laboratory's cutoff concentrations of 100 and 25 ng/mL, respectively. This was true, as well, at alternative EtG/EtS cutoff concentrations of 200/50, 300/75, and 400/100 ng/mL. PEth was more likely than EtG/EtS to be positive in participants previously diagnosed with alcohol use disorders (AUD), whereas EtG/EtS was more likely than PEth to be positive in participants without AUD. In this study, blood PEth was the most sensitive biomarker for evidencing alcohol use.  相似文献   
102.
A cell culture system is described in which purified mononuclear phagocytes may be cultured with a cartilage substrate which is radiolabelled in its proteoglycan. Resident mouse peritoneal macrophages degraded this substrate, and did so more avidly if cultured in direct contact with it. There was no evidence for complete intralysosomal degradation of the proteoglycan of the cartilage. Lysates were found to contain considerable activity at pH 7, which was inhibited by the presence of 10% serum, or by boiling the lysate.

Proximity of macrophages to the substrate did not induce selective release of the lysosomal marker enzyme hexosaminidase, and concentrated enzymes secreted from the macrophages after treatment with the lysosomotropic agent ammonium chloride were ineffective in degrading cartilage at neutral pH.

The active enzyme in macrophage lysates at neutral pH was found to be sedimentable by 100,000 × g centrifugation for 1 hour, in absence of lysosomal protective agents. There is evidence for a cell membrane-associated process in the degradation of cartilage by these cells, which may be a proteolytic, endoglycosidic or free radical-mediated event.  相似文献   
103.
《Dental materials》2020,36(6):755-764
ObjectiveIn vital pulp therapy (VPT), a barrier is created with appropriate capping to protect the remaining pulp and thus maintain pulp vitality. Here, we evaluated the feasibility of a biphasic calcium phosphate cement (CPC)–calcium sulfate hemihydrate (CSH) biomaterial containing simvastatin (Sim) and collagenase (Col) for VPT.MethodsCombinations of varying CPC and CSH concentrations were analyzed for their handling properties and setting times, with their structures observed through scanning electron microscopy–energy dispersive X-ray spectrometry (SEM-EDS). Drug release patterns of simvastatin and collagenase combined with CPC–CSH (CPC–CSH–Sim–Col) were also analyzed, followed by biocompatibility and bioactivity tests on human dental pulp stem cells (hDPSCs) and in vivo animal study in canine models; the in vivo results were obtained through microcomputed tomography and histological analysis.ResultsThe results revealed that 70 wt% CPC (CPC7) with 30 wt% CSH (CSH3) exhibited optimal setting time and porous structure for clinical use. The cell viability and cytotoxicity analysis demonstrated that CPC7–CSH3 with or without simvastatin or collagenase did not injure hDPSCs. In vivo, the CPC7–CSH3–Sim–Col induced dentin bridge formation.SignificanceCPC7–CSH3–Sim–Col in this study has great potential as a VPT biomaterial to enhance the dentin bridge formation.  相似文献   
104.
BackgroundNeurosteroids affect the balance between neuroexcitation and neuroinhibition but have been little studied in migraine. We compared the serum levels of pregnenolone sulfate, pregnanolone and estradiol in women with menstrually-related migraine and controls and analysed if a correlation existed between the levels of the three hormones and history of migraine and age.MethodsThirty women (mean age ± SD: 33.5 ± 7.1) with menstrually-related migraine (MM group) and 30 aged- matched controls (mean age ± SD: 30.9 ± 7.9) participated in the exploratory study. Pregnenolone sulfate and pregnanolone serum levels were analysed by liquid chromatography-tandem mass spectrometry, while estradiol levels by enzyme-linked immunosorbent assay.ResultsSerum levels of pregnenolone sulfate and pregnanolone were significantly lower in the MM group than in controls (pregnenolone sulfate: P = 0.0328; pregnanolone: P = 0.0271, Student’s t-test), while estradiol levels were similar. In MM group, pregnenolone sulfate serum levels were negatively correlated with history of migraine (R2 = 0.1369; P = 0.0482) and age (R2 = 0.2826, P = 0.0025) while pregnenolone sulfate levels were not age-related in the control group (R2 = 0.04436, P = 0.4337, linear regression analysis).ConclusionLow levels of both pregnanolone, a positive allosteric modulator of the GABAA receptor, and pregnenolone sulfate, a positive allosteric modulator of the NMDA receptor, involved in memory and learning, could contribute either to headache pain or the cognitive dysfunctions reported in migraine patients. Overall, our results agree with the hypothesis that migraine is a disorder associated with a loss of neurohormonal integrity, thus supporting the therapeutic potential of restoring low neurosteroid levels in migraine treatment.Supplementary InformationThe online version contains supplementary material available at 10.1186/s10194-021-01231-9.  相似文献   
105.
目的研制可注射α-CSH-nano-HA/PHBV-PEG顺铂释药系统,为骨转移瘤提供新型的局部药物缓释系统。方法α-CSH-nano-HA/PHBV-PEG载顺铂制成可注射用α-CSH-nano-HA/PHBV-PEG cis-platinum缓释微球,研究其结构、释药特性、可注射性以及力学性能。结果(1)第1、3、5、7天缓释微球的释药浓度分别为97.5、90.7、83.2、68.5μg/mL,第7天后趋于稳定。(2)可注射α-CSH-nano-HA/PHBV-PEG顺铂释药系统在液固比为0.7时可注射性强,与此同时缓释药系统随着液固比的增大凝固时间延长。结论α-CSH-nano-HA/PHBVPEG顺铂释药系统具有良好的注射性能和缓释作用。  相似文献   
106.

Background:

Aluminum phosphide (ALP) (celphos) is an agricultural pesticide commonly implicated in poisoning. Literature pertaining to the clinical manifestations and treatment outcome of its poisoning among children is limited.

Materials and Methods:

A retrospective chart review was conducted of the medical records of 30 children aged less than 14 years admitted to pediatric intensive care unit (PICU) of a tertiary care hospital in northern India. Demographic, clinical, and laboratory parameters were recorded. The outcome was categorized into “survivors” and “nonsurvivors.”

Results:

The Mean (SD) age of the enrolled children [19 males (63.3%)] was 8.55 (3.07) years. Among the 30 children, 14 (46.67%) were nonsurvivors and the rest 16 (53.33%) were survivors. Nonsurvivors had ingested significantly higher doses of ALP (P < 0.001), and showed higher time lag to PICU transfer (P 0.031), presence of abnormal radiological findings on chest skiagram (P = 0.007), and a higher Pediatric Risk of Mortality (PRISM) III score (P < 0.001) at admission. Use of magnesium sulfate was associated significantly with survival [odds ratio (OR) (95% CI): 0.11 (0.02-0.66); P 0.016].

Conclusion:

The present study highlights that survival among children with ALP poisoning is predicted by dose of ALP ingestion, time lag to medical attention, and higher PRISM score at admission. Use of magnesium sulfate could be associated with better survival among them.  相似文献   
107.
A significant number of lower extremity fractures result in mal‐union necessitating effective treatments to restore ambulation. Prior research in diabetic animal fracture models demonstrated improved healing following local insulin application to the fracture site and indicated that local insulin therapy can aid bone regeneration, at least within an insulin‐dependent diabetic animal model. This study tested whether local insulin therapy could accelerate femur fracture repair in normal, non‐diabetic rats. High (20 units) and low (10 units) doses of insulin were delivered in a calcium sulfate carrier which provided sustained release of the exogenous insulin for 7 days after fracture. Histomorphometry, radiographic scoring, and torsional mechanical testing were used to measure fracture healing. The fracture calluses from rats treated with high‐dose insulin had significantly more cartilage than untreated rats after 7 and 14 days of healing. After 4 weeks of healing, femurs from rats treated with low‐dose insulin had significantly higher radiographic scores and mechanical strength (p < 0.05), compared to the no treatment control groups. The results of this study suggest that locally delivered insulin is a potential therapeutic agent for treating bone fractures. Further studies are necessary, such as large animal proof of concepts, prior to the clinical use of insulin for bone fracture treatment. © 2012 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 31: 776–782, 2013  相似文献   
108.
The objectives of this study were to explore sodium dodecyl sulfate (SDS) and Soluplus on the crystallization inhibition and dissolution of felodipine (FLDP) extrudates by bottom-up and top-down approaches. FLDP extrudates with Soluplus and SDS were prepared by hot melt extrusion, and characterized by polarized light microscopy, differential scanning calorimetry, and fourier transform infrared spectroscopy. Results indicated that Soluplus inhibited FLDP crystallization, and the whole amorphous solid dispersions (ASDs) were binary FLDP-Soluplus (1:3) and ternary FLDP-Soluplus-SDS (1:2:0.15~0.3 and 1:3:0.2~0.4) extrudates. Internal SDS (5%-10%) decreased glass transition temperatures of FLDP-Soluplus-SDS ternary ASDs without presenting molecular interactions with FLDP or Soluplus. The enhanced dissolution rate of binary or ternary Soluplus-rich ASDs in the nonsink condition of 0.05% SDS was achieved. Bottom-up approach indicated that Soluplus was a much stronger crystal inhibitor to the supersaturated FLDP in solutions than SDS. Top-down approach demonstrated that SDS enhanced the dissolution of Soluplus-rich ASDs via wettability and complexation with Soluplus to accelerate the medium uptake and erosion kinetics of extrudates, but induced FLDP recrystallization and resulted in incomplete dissolution of FLDP-rich extrudates. In conclusion, top-down approach is a promising strategy to explore the mechanisms of ASDs' dissolution, and small amount of SDS enhances the dissolution rate of polymer-rich ASDs in the nonsink condition.  相似文献   
109.
It is important to address the periodontitis-associated bacteria in the residual subgingival plaque after scaling and root planing to successfully treat periodontitis. In this study, we explored the possibility of exploiting the ion pairing/complexation of minocycline, Ca2+, and sulfate/sulfonate-bearing biopolymers to develop an intrapocket delivery system of minocycline as an adjunct to scaling and root planing. Minocycline-calcium-dextran sulfate complex microparticles were synthesized from minocycline, CaCl2, and dextran sulfate. They were characterized using Fourier-transform infrared spectroscopy, scanning electron microscopy, and energy-dispersive X-ray spectroscopy. An in vitro release study was conducted to evaluate the release kinetics of minocycline from these microparticles. Agar disk diffusion assays and biofilm-grown bacteria assays were used to assess antibacterial capability. High loading efficiency (96.98% ± 0.12%) and high loading content (44.69% ± 0.03%) for minocycline were observed for these complex microparticles. Mino-Ca-DS microparticles achieved sustained release of minocycline for at least 9 days at pH 7.4 and 18 days at pH 6.4 in phosphate-buffered saline, respectively. They also demonstrated potent antimicrobial effects against Streptococcus mutans and Aggregatibacter actinomycetemcomitans in agar disk diffusion and biofilm assays. These results suggested that the ion pairing/complexation of minocycline, Ca2+, and sulfonate/sulfate-bearing biopolymers can be exploited to develop complex microparticles as local delivery systems for periodontitis treatment.  相似文献   
110.
目的:为了确定硫酸核糖霉素分子式中硫酸的数目,并选择适合的方法控制其硫酸盐的含量。方法:建立了高效液相色谱-蒸发光散射法(HPLC-ELSD)对硫酸核糖霉素的硫酸盐(SO4)含量进行测定,并开发出了同样适用的离子色谱电导法(HPIC-CD)进行结果比对。同时采用《中国药典》方法测定硫酸核糖霉素的酸碱度。结果:HPLC-ELSD法,硫酸盐(SO4)在15~250 μg·mL-1范围内线性良好,检测限和定量限分别为0.16 μg和0.25 μg,回收率为101.1%;HPIC-CD法,硫酸盐(SO4)在20~180 μg·mL-1范围内线性良好,检测限和定量限分别为0.17 ng和0.50 ng,回收率为99.8%。结论:两种硫酸盐测定方法,专属性强,灵敏度高,重复性好,测定结果无显著性差异,分子式中硫酸的数目约为1.5,进一步发现,硫酸盐含量和溶液pH值呈显著负相关,并具有一定的线性关系,酸碱度检查可以控制硫酸盐的含量。  相似文献   
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