15 research outputs found
Особенности процесса трещинообразования в массиве при управлении его газодинамикой
Исследован процесс сдерживания перехода угля из потенциально устойчивого состояния
в стадию бурного разрушения. Ей, как правило, предшествует некоторый промежуток времени относительного затишья. Особенно важно улавливать этот момент среди массы различных
откликов массива на ведение горных работ. Одним из вариантов управления развитием и релаксацией системы трещин может служить физико-химическая обработка.The inhibition process of coal transition from the potentially stable state in the stage of stormy destruction is investigation. As a rule, to it is preceded some interval of relative time calm. It
is especially important to catch this moment among mass of different responses of array on the
conduct of mountain works. Physical and chemical treatment can serve as one of control variants
the development and relaxation of the cracks system
Synthesis and Evaluation of Polymyxins Bearing Reductively Labile Disulfide-Linked Lipids
Polymyxins are a class of lipopeptide anti-infective agents with potent and specific activity against Gram-negative bacteria. While toxicity concerns associated with polymyxin B and E (colistin) have historically limited their clinical application, today they are increasingly used as last-resort antibiotics given the rise of multidrug-resistant Gram-negative pathogens. The adverse side effects of polymyxins are well known, particularly as related to their nephrotoxicity. Here, we describe the synthesis and evaluation of a novel series of polymyxin analogues, aimed at reducing their nephrotoxic effects. Using a semisynthetic approach, we explored modifications of the exocyclic part of the polymyxin scaffold, namely, the terminal amino acid and lipophilic tail. By incorporating a reductively labile disulfide linkage in the lipid tail, we obtained novel polymyxins that exhibit potent antibacterial activity on par with polymyxin B but with reduced toxicity toward human renal proximal tubular epithelial cells
Effects of Anacetrapib in Patients with Atherosclerotic Vascular Disease
BACKGROUND:
Patients with atherosclerotic vascular disease remain at high risk for cardiovascular events despite effective statin-based treatment of low-density lipoprotein (LDL) cholesterol levels. The inhibition of cholesteryl ester transfer protein (CETP) by anacetrapib reduces LDL cholesterol levels and increases high-density lipoprotein (HDL) cholesterol levels. However, trials of other CETP inhibitors have shown neutral or adverse effects on cardiovascular outcomes.
METHODS:
We conducted a randomized, double-blind, placebo-controlled trial involving 30,449 adults with atherosclerotic vascular disease who were receiving intensive atorvastatin therapy and who had a mean LDL cholesterol level of 61 mg per deciliter (1.58 mmol per liter), a mean non-HDL cholesterol level of 92 mg per deciliter (2.38 mmol per liter), and a mean HDL cholesterol level of 40 mg per deciliter (1.03 mmol per liter). The patients were assigned to receive either 100 mg of anacetrapib once daily (15,225 patients) or matching placebo (15,224 patients). The primary outcome was the first major coronary event, a composite of coronary death, myocardial infarction, or coronary revascularization.
RESULTS:
During the median follow-up period of 4.1 years, the primary outcome occurred in significantly fewer patients in the anacetrapib group than in the placebo group (1640 of 15,225 patients [10.8%] vs. 1803 of 15,224 patients [11.8%]; rate ratio, 0.91; 95% confidence interval, 0.85 to 0.97; P=0.004). The relative difference in risk was similar across multiple prespecified subgroups. At the trial midpoint, the mean level of HDL cholesterol was higher by 43 mg per deciliter (1.12 mmol per liter) in the anacetrapib group than in the placebo group (a relative difference of 104%), and the mean level of non-HDL cholesterol was lower by 17 mg per deciliter (0.44 mmol per liter), a relative difference of -18%. There were no significant between-group differences in the risk of death, cancer, or other serious adverse events.
CONCLUSIONS:
Among patients with atherosclerotic vascular disease who were receiving intensive statin therapy, the use of anacetrapib resulted in a lower incidence of major coronary events than the use of placebo. (Funded by Merck and others; Current Controlled Trials number, ISRCTN48678192 ; ClinicalTrials.gov number, NCT01252953 ; and EudraCT number, 2010-023467-18 .)
The autonomic stress-induced hyperthermia response is not enhanced by several anxiogenic drugs
Environmental enrichment has antidepressant-like action without improving learning and memory deficits in olfactory bulbectomized rats
Depression, especially in the elderly, is associated with poor cognitive functioning. Exercise has received much attention in the treatment for depression and also dementia. Here we studied the effect of an enriched environment combined with voluntary exercise (EE/VE) on the olfactory bulbectomized (OBX) rat. The OBX rat is hyperactive in an open field, which is normalized by chronic antidepressant treatment, and suffers from learning and memory impairments. Neurotrophic factors are thought to be involved in the antidepressant action of EE/VE. Hyperactivity and cognitive functioning (both hippocampal dependent and independent tasks) were investigated before and after EE/VE. We quantified hippocampal mRNA levels of the neurotrophic factors BDNF, VGF and VEGF. VEGF receptor (FLK-1) inhibition was achieved by i.c.v administration of the antagonist SU5416 during the period of EE/VE. OBX almost completely blocked fear memory acquired either 48 h or 28 days before surgery. EE/EV normalized OBX-induced hyperactivity in open field, while having no effect on the decrease in hippocampal dependent learning and memory. VEGF mRNA levels in hippocampus were significantly increased both in OBX and control rats following EE/VE. OBX reduced BDNF mRNA levels, but EE did not reverse this. Inhibition of the FLK-1 receptor did not suppress EE/VE induced normalization of the hyperactivity of the OBX rat. The lack of effect of EE/VE on cognitive parameters, while normalizing hyperactivity, suggests different neuronal mechanisms underlying OBX-induced behavioral changes. Since EE/VE still normalizes the OBX-induced hyperactivity while the FLK-1 receptor was blocked, we assume that VEGF is not obligatory for the antidepressant effect of EE/VE. This article is part of a Special Issue entitled 'Anxiety and Depression'
Synthesis and Evaluation of Polymyxins Bearing Reductively Labile Disulfide-Linked Lipids
Polymyxins are a class of lipopeptide anti-infective
agents with
potent and specific activity against Gram-negative bacteria. While
toxicity concerns associated with polymyxin B and E (colistin) have
historically limited their clinical application, today they are increasingly
used as last-resort antibiotics given the rise of multidrug-resistant
Gram-negative pathogens. The adverse side effects of polymyxins are
well known, particularly as related to their nephrotoxicity. Here,
we describe the synthesis and evaluation of a novel series of polymyxin
analogues, aimed at reducing their nephrotoxic effects. Using a semisynthetic
approach, we explored modifications of the exocyclic part of the polymyxin
scaffold, namely, the terminal amino acid and lipophilic tail. By
incorporating a reductively labile disulfide linkage in the lipid
tail, we obtained novel polymyxins that exhibit potent antibacterial
activity on par with polymyxin B but with reduced toxicity toward
human renal proximal tubular epithelial cells
Synthesis and Evaluation of Polymyxins Bearing Reductively Labile Disulfide-Linked Lipids
Polymyxins are a class of lipopeptide anti-infective
agents with
potent and specific activity against Gram-negative bacteria. While
toxicity concerns associated with polymyxin B and E (colistin) have
historically limited their clinical application, today they are increasingly
used as last-resort antibiotics given the rise of multidrug-resistant
Gram-negative pathogens. The adverse side effects of polymyxins are
well known, particularly as related to their nephrotoxicity. Here,
we describe the synthesis and evaluation of a novel series of polymyxin
analogues, aimed at reducing their nephrotoxic effects. Using a semisynthetic
approach, we explored modifications of the exocyclic part of the polymyxin
scaffold, namely, the terminal amino acid and lipophilic tail. By
incorporating a reductively labile disulfide linkage in the lipid
tail, we obtained novel polymyxins that exhibit potent antibacterial
activity on par with polymyxin B but with reduced toxicity toward
human renal proximal tubular epithelial cells
Bacterial Lipopolysaccharide Increases Serotonin Metabolism in Both Medial Prefrontal Cortex and Nucleus Accumbens in Male Wild Type Rats, but Not in Serotonin Transporter Knockout Rats
It is well known that bacterial lipopolysaccharides (LPS) both increases proinflammatory cytokines and produces sickness behavior, including fatigue and anhedonia (i.e., the inability to experience pleasure). Previously, we have shown that intraperitoneally (i.p.) administered LPS increased extracellular monoamine metabolite levels in the nucleus accumbens (NAc) and medial prefrontal cortex (mPFC), which was completely, or at least partly, prevented by pretreatment with a triple reuptake inhibitor that also blocks the serotonin (5-HT) transporter (SERT). This suggests indirectly, that LPS may enhance SERT transporter activity, and consequently, increase removal of 5-HT from the synaptic cleft, and increase metabolism of 5-HT. In the present study, we focus more specifically on the role of SERT in this increased metabolism by using rats, that differ in SERT expression. Therefore, the effects of an intraperitoneal LPS injection on extracellular concentrations of 5-HT and its metabolite 5-hydroxyindoleacetic acid (5-HIAA) were investigated by in vivo microdialysis in the NAc and mPFC of wild type (SERT+/+), heterozygous (SERT+/−) and knockout (SERT−/−) rats. Here, we show that LPS-induced 5-HIAA formation in male rats, is significantly increased in SERT+/+ rats in both the NAc and mPFC, whereas this increase is partly or totally abolished in SERT+/− and SERT−/− rats, respectively. Thus, the present study supports the hypothesis that systemic LPS in male rats increases SERT function and consequently enhances 5-HT uptake and metabolism in both the NAc and mPFC
Synthesis and Evaluation of Polymyxins Bearing Reductively Labile Disulfide-Linked Lipids
Polymyxins are a class of lipopeptide anti-infective agents with potent and specific activity against Gram-negative bacteria. While toxicity concerns associated with polymyxin B and E (colistin) have historically limited their clinical application, today they are increasingly used as last-resort antibiotics given the rise of multidrug-resistant Gram-negative pathogens. The adverse side effects of polymyxins are well known, particularly as related to their nephrotoxicity. Here, we describe the synthesis and evaluation of a novel series of polymyxin analogues, aimed at reducing their nephrotoxic effects. Using a semisynthetic approach, we explored modifications of the exocyclic part of the polymyxin scaffold, namely, the terminal amino acid and lipophilic tail. By incorporating a reductively labile disulfide linkage in the lipid tail, we obtained novel polymyxins that exhibit potent antibacterial activity on par with polymyxin B but with reduced toxicity toward human renal proximal tubular epithelial cells
The 5-HT1A/1B-receptor agonist eltoprazine increases both catecholamine release in the prefrontal cortex and dopamine release in the nucleus accumbens and decreases motivation for reward and "waiting" impulsivity, but increases "stopping" impulsivity
The 5-HT1A/1B-receptor agonist eltoprazine has a behavioral drug signature that resembles that of a variety of psychostimulant drugs, despite the differences in receptor binding profile. These psychostimulants are effective in treating impulsivity disorders, most likely because they increase norepinephrine (NE) and dopamine (DA) levels in the prefrontal cortex. Both amphetamine and methylphenidate, however, also increase dopamine levels in the nucleus accumbens (NAc), which has a significant role in motivation, pleasure, and reward. How eltoprazine affects monoamine release in the medial prefrontal cortex (mPFC), the orbitofrontal cortex (OFC), and the NAc is unknown. It is also unknown whether eltoprazine affects different forms of impulsivity and brain reward mechanisms. Therefore, in the present study, we investigate the effects of eltoprazine in rats in the following sequence: 1) the activity of the monoaminergic systems using in vivo microdialysis, 2) motivation for reward measured using the intracranial self-stimulation (ICSS) procedure, and finally, 3) "waiting" impulsivity in the delay-aversion task, and the "stopping" impulsivity in the stop-signal task. The microdialysis studies clearly showed that eltoprazine increased DA and NE release in both the mPFC and OFC, but only increased DA concentration in the NAc. In contrast, eltoprazine decreased 5-HT release in the mPFC and NAc (undetectable in the OFC). Remarkably, eltoprazine decreased impulsive choice, but increased impulsive action. Furthermore, brain stimulation was less rewarding following eltoprazine treatment. These results further support the long-standing hypothesis that "waiting" and "stopping" impulsivity are regulated by distinct neural circuits, because 5-HT1A/1B-receptor activation decreases impulsive choice, but increases impulsive action