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121.
Increased functional brain response towards alcohol-associated stimuli is a neural hallmark of alcohol dependence and a promising target for pharmacotherapy. For the first time, we assessed the effects of individually titrated high-dose baclofen on cue reactivity and functional connectivity in alcohol-dependent (AD) patients in a randomized controlled trial (RCT).We investigated 23 recently detoxified AD patients and 23 matched healthy controls (HC) with a cue reactivity functional magnetic resonance imaging task. Patients were further scanned at baseline without medication and during treatment with high-dose baclofen/placebo (30–270 mg/d). Analyses were conducted for alcohol cue-elicited brain response, alcohol cue-modulated and stimulus-independent functional connectivity with left ventral tegmental area (VTA) as seed region.At baseline, AD patients (N?=?23) showed increased cue-elicited brain activation in the ventral striatum (VS) compared to HC (N?=?23), which was decreased at the second scanning session compared to baseline. Patients receiving baclofen (N?=?10) showed a significant stronger decrease in cue-elicited brain activation in left orbitofrontal cortex (OFC), bilateral amygdala and left VTA than patients receiving placebo (N?=?13). Treatment with baclofen further led to a decrease in alcohol cue-modulated functional connectivity between left VTA and left anterior cingulate cortex (ACC) as well as left medial prefrontal cortex (MPFC). Regarding clinical outcome, significantly more patients of the baclofen group remained abstinent during the high-dose period.Baclofen specifically decreased cue-elicited brain responses in areas known to be involved in the processing of salient (appetitive and aversive) stimuli. Treatment with high-dose baclofen seems to provide a pharmacological relief of this neural “warning signal” evoked by alcohol-related cues, thereby possibly supporting patients in remaining abstinent.Trial Registration Identifier of the main trial [BACLAD study] at clinicaltrials.gov: NCT01266655.  相似文献   
122.
Background: Dual epidemics of injection drug use and blood-borne disease, characterized as “syndemics,” are present in a range of settings. Behaviors that drive such syndemics are particularly prevalent among mobile drug-using populations, for whom cross-border migration may pose additional risks. Objectives: This narrative review aims to characterize the risk factors for injection drug use initiation associated with migration, employing a risk environment framework and focusing on the San Diego–Tijuana border region as the most dynamic example of these phenomena. Methods: Based on previous literature, we divide migration streams into three classes: intra-urban, internal, and international. We synthesized existing literature on migration and drug use to characterize how mobility and migration drive the initiation of injection drug use, as well as the transmission of hepatitis and HIV, and to delineate how these might be addressed through public health intervention. Results: Population mixing between migrants and receiving communities and the consequent transmission of social norms about injection drug use create risk environments for injection drug use initiation. These risk environments have been characterized as a result of local policy environments, injection drug use norms in receiving communities, migration-related stressors, social dislocation, and infringement on the rights of undocumented migrants. Conclusion: Policies that exacerbate risk environments for migrants may inadvertently contribute to the expansion of epidemics of injection-driven blood-borne disease. Successful interventions that address emerging syndemics in border regions may therefore need to be tailored to migrant populations and distinguish between the vulnerabilities experienced by different migration classes and border settings.  相似文献   
123.
The interaction of trolox with ammonia, alkylamines of different classes, and amino derivatives of heterocyclic compounds, including nitroxyl radicals and alkaloids, led to the production of ammonium salts called ion conjugates (ICs). Five ICs were characterised by X-ray diffraction. This is the first time a wide range of ICs were made from trolox with amines, and ESI-MS data demonstrated they have the potential to generate pseudomolecular [(A?B+)?+?H]+ ions. For all obtained trolox ICs, a significant increase (1–3 orders of magnitude) in water solubility was achieved while retaining high antioxidant activity. ICs synthesised from two biologically active fragments may be used to create polyfunctional agents with varying solubility and bioavailability.  相似文献   
124.
Extracellular vesicles (EV) are secreted signaling entities that enhance various pathological processes when released in response to cellular stresses. Respiratory exposures such as cigarette smoke and air pollution exert cellular stresses and are associated with an increased risk of several chronic diseases. The aim of this review was to examine the evidence that modifications in EV contribute to respiratory exposure-associated diseases. Publications were searched using PubMed and Google Scholar with the search terms (cigarette smoke OR tobacco smoke OR air pollution OR particulate matter) AND (extracellular vesicles OR exosomes OR microvesicles OR microparticles OR ectosomes). All original research articles were included and reviewed. Fifty articles were identified, most of which investigated the effect of respiratory exposures on EV release in vitro (25) and/or on circulating EV in human plasma (24). The majority of studies based their main observations on the relatively insensitive scatter-based flow cytometry of EV (29). EV induced by respiratory exposures were found to modulate inflammation (19), thrombosis (13), endothelial dysfunction (11), tissue remodeling (6), and angiogenesis (3). By influencing these processes, EV may play a key role in the development of cardiovascular diseases and chronic obstructive pulmonary disease and possibly lung cancer and allergic asthma. The current findings warrant additional research with improved methodologies to evaluate the contribution of respiratory exposure-induced EV to disease etiology, as well as their potential as biomarkers of exposure or risk and as novel targets for preventive or therapeutic strategies.  相似文献   
125.
Lignans are widely distributed in plants and exhibit significant pharmacological effects, including anti-tumor and antioxidative activities. Here, we describe the total synthesis of schizandriside (1), a compound we previously isolated from Saraca asoca by monitoring antioxidative activity using the 1,1-diphenyl-2-picrylhydrazyl radical scavenging assay. Starting from a tandem Michael-aldol reaction, the lignan skeleton was synthesized in 6 steps, including a cyclization step. To determine the stereochemistry of 1, we synthesized the natural product (±)-isolariciresinol (18) from alcohol 17. Comparison of the spectral data showed good agreement. Glycosylation was investigated using four different glycosyl donors. Only the Koenigs–Knorr condition using silver trifluoromethanesulfonate with 1,1,3,3-tetramethylurea provided the glycosylated product. Deprotection and purification using reverse-phase high-performance liquid chromatography gave schizandriside (1) and its diastereomer saracoside (2). Synthesized 1, 2 and 18 showed antioxidant activity with IC50?=?34.4, 28.8, 53.0 μM, respectively.  相似文献   
126.
Resveratrol (RL), a natural polyphenol, is known for its diverse biological effects against various human cancer cell lines. But low aqueous solubility, poor bioavailability, and stability limit its efficacy against prostate cancer. In this study polymeric nanoparticles encapsulating resveratrol (RLPLGA) were designed and their cytotoxic and mode of apoptotic cells death against prostate cancer cell line (LNCaP) was determined. Nanoparticles were prepared by solvent displacement method and characterized for particle size, TEM, entrapment efficiency, DSC and drug release study. RLPLGA exhibited a significant decrease in cell viability with 50% and 90% inhibitory concentration (IC50 and IC90) of 15.6?±?1.49 and 41.1?±?2.19?μM respectively against the LNCaP cells. This effect was mediated by apoptosis as confirmed by cell cycle arrest at G1-S transition phase, externalization of phosphatidylserine, DNA nicking, loss of mitochondrial membrane potential and reactive oxygen species generation in LNCaP cells. Furthermore, significantly greater cytotoxicity to LNCaP cells was observed with nanoparticles as compared to that of free RL at all tested concentrations. RLPLGA nanoparticles presented no adverse cytotoxic effects on murine macrophages even at 200?μM. Our findings support the potential use of developed resveratrol loaded nanoparticle for the prostate cancer chemoprevention/ chemotherapy with no adverse effect on normal cells.  相似文献   
127.

Background

Hospitalization can contribute to insomnia in many patients and is usually treated symptomatically. However, sedative/hypnotic misuse is associated with complications in this population, especially in the elderly. Such complications include dizziness, falls and over-sedation. Due to the implicit dangers, widespread use of these drugs for insomnia, particularly in older patients, has been discouraged by many hospitals. The aim of this study was to review and evaluate prescribing patterns and to optimize the use of the sedative/hypnotic agents through daily pharmacy interventions at a community hospital.

Methods

This was a biphasic before and after study. Data on sedative/hypnotic use was collected retrospectively for a 2-month period and a sample of 100 patients was randomly selected for analysis. A 2-month prospective phase followed, in which daily orders were reviewed by one pharmacy resident and recommendations made to discontinue any unnecessary, newly prescribed sedative/hypnotic orders when appropriate. Finally, results of both phases were compared for any differences in patient demographics, being prescribed more than one sedative/hypnotic, and complications documented.

Results

During the prospective phase, pharmacist interventions led to the discontinuation of 25% of a total of 97 sedative/hypnotic orders in 97 patients. The number of patients receiving more than one sedative/hypnotic agents in the intervention group was significantly lower than the retrospective control group (15 Vs. 34, P?=?0.0026). The incidence of complications was not significantly different between the control and intervention groups for the following: over-sedation, falls and delirium (p?=?0.835, p?=?0.185, p?=?0.697, respectively).

Conclusion

This study suggests that the use of sedative/hypnotics in the inpatient units (excluding the critical care unit), is somewhat prevalent, and many patients may be on more than one sedative/hypnotic, which could potentially cause cumulative harm. During the intervention phase, 25% of the total in-hospital orders for sedative/hypnotics were discontinued following recommendations made by a pharmacist, and significantly lower number of patients receiving duplicate sedative/hypnotics was noted. Further efforts should be implemented to avoid unnecessary sedative/hypnotic initiation in hospitalized patients, and to ensure monitoring by pharmacists is optimized.  相似文献   
128.
129.
Journal of Natural Medicines - A new amide, named dehydropropylpantothenamide (1), was obtained by a co-culture of Nocardia tenerifensis IFM 10554T in the presence of the mouse macrophage-like cell...  相似文献   
130.
中文:背景患者入院后可从不当消毒的环境表面获得多药耐药菌和艰难梭菌。本文确定了3种强化的终末消毒(入住同一病房的两名患者之间的消毒)策略,对感染耐甲氧西林金黄色葡萄球菌(MRSA)、耐万古霉素肠球菌(VRE)、艰难梭菌(CD)和多重耐药不动杆菌的影响。方法本文在美国东南部的9家医院开展了一项务实的、集群-随机、交叉研究。凡曾有感染或定植目标细菌感染患者居住过的病房,患者出院后随机采取4种消毒策略中的一种方法进行终末消毒:对照(季胺盐类消毒剂消毒,但凡遇到CD采用含氯消毒剂);UV(季胺盐类+UV-C消毒,但凡遇到CD采用含氯消毒剂+UV-C);含氯消毒剂;含氯消毒剂+UV-C。凡入住目标病房的患者被列为暴露人群。这4种终末消毒方法分别在每家医院连续实施7个月的周期。本文随机设计这几种消毒策略在每家医院内的实施顺序(1:1:1:1)。主要产出的结果是,观察暴露患者中目标细菌的感染的发生或定植情况,以及ITT人群中暴露患者CD感染发生率。本研究ClinicalTrials.gov注册编号:NCT01579370。结果共有31 226名患者暴露,其中21 395(69%)符合标准,包括4 916名对照组,5 178名UV组,5 438名含氯消毒剂组,以及5 863名含氯消毒剂+UV组。在对照组中,22 426个暴露日中有115名患者发生目标细菌的感染(51.3/10000暴露日)。在标准清洁策略的基础上增加UV消毒的暴露患者,其目标细菌感染的发生率明显较低(n=76;33.9/10 000暴露日;RR:0.70,95%CI:0.50~0.988;P=0.036)。含氯消毒剂组(n=101;41.6/10 000暴露日;RR:0.85,95%CI:0.69~1.04;P=0.116),或含氯消毒剂+UV组患者(n=131;45.6/10 000暴露日;RR:0.91,95%CI:0.76~1.09;P=0.303)的目标细菌的感染率,其差异无统计学意义。同样,在含氯消毒剂的基础上增加UV消毒,暴露患者中CD感染率也没有发生改变((n=38 vs 36;30.4 vs 31.6/10 000暴露日;RR:1.0,95%CI:0.57-1.75;P=0.997)。解释污染的医疗机构环境是获得病原微生物的重要来源;强化终末消毒可以降低这一风险。  相似文献   
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