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71.
AbstractBackground: The aim of this study was to characterize human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS)-related knowledge and stigma among methadone maintenance treatment (MMT) patients and evaluate the contribution of an educational lecture in reducing risky behavior and unjustified overprotective behavior due to fear and stigma among MMT patients. Methods: Patients from an MMT clinic within a tertiary medical center were invited to an educational lecture on HIV/AIDS. Seventy participants (of current 330) were chosen by a random sample (December 2015), plus at-risk patients and HIV patients. Attendee compliance and change in scores of questionnaires on knowledge (modified HIV-K-Q-22) and on sexual and injection behaviors were studied. Results: Forty-six patients (65.7% compliance) attended the lecture, and their knowledge and behavior scores improved 2?weeks post-lecture (knowledge: from 14.2?±?3 to 19.0?±?2.2 [P?<?.0005], sexual behavior: from 12.1?±?2.9 to 8.8?±?3.0 [P?<?.0005], and injection behavior: from 7.3?±?6.2 to 0.2?±?1.3 [P?<?.0005]). The unjustified fear of proximity to HIV carriers reported by 50% attendees fell to 35% post-lecture. Eight months post-lecture, the scores on knowledge and risky behavior of 21 randomly chosen attendees were still better than pre-lecture scores (knowledge: 15.4?±?2.3 vs. 17.2?±?1.8 [paired t test, P?=?.001], sexual behavior: 13.2?±?2.3 vs. 9.7?±?2.9 [P?<?.0005], and injection behavior: 9.3?±?5.6 vs. 2.8?±?3.1 [P?<?.0005]). Drug abuse and treatment adherence were not related to intervention and to risky behavior. Conclusions: More knowledge, less fear, and less risky behavior immediately and at 8?months post-lecture reflect the success and importance of the educational intervention. Future efforts are needed in order to reduce ignorance and fear associated with HIV/AIDS. 相似文献
72.
Amir Segev Adva S Rubin Hila Abush Gal Richter-Levin Irit Akirav 《Neuropsychopharmacology》2014,39(4):919-933
Most psychiatric disorders are characterized by emotional memory or learning disturbances. Chronic mild stress (CMS) is a common animal model for stress-induced depression. Here we examined whether 3 days of treatment using the CB1/2 receptor agonist WIN55,212-2 could ameliorate the effects of CMS on emotional learning (ie, conditioned avoidance and extinction), long-term potentiation (LTP) in the hippocampal-accumbens pathway, and depression-like symptoms (ie, coping with stress behavior, anhedonia, and weight changes). We also examined whether the ameliorating effects of WIN55,212-2 on behavior and physiology after CMS are mediated by CB1 and glucocorticoid receptors (GRs). Rats were exposed to CMS or handled on days 1–21. The agonist WIN55,212-2 or vehicle were administered on days 19–21 (IP; 0.5 mg/kg) and behavioral and electrophysiological measures were taken on days 23 and 28. The CB1 receptor antagonist AM251 (IP; 0.3 mg/kg) or the GR antagonist RU-38486 (IP; 10 mg/kg) were co-administered with WIN55,212-2. Our results show that CMS significantly modified physiological and behavioral reactions, as observed by the impairment in avoidance extinction and LTP in the hippocampal-accumbens pathway, and the alterations in depression-like symptoms, such as coping with stress behavior, weight gain, and sucrose consumption. The most significant effect observed in this study was that 3 days of WIN55,212-2 administration prevented the CMS-induced alterations in emotional memory (ie, extinction) and plasticity. This effect was mediated by CB1 receptors as the CB1 receptor antagonist AM251 prevented the ameliorating effects of WIN55,212-2 on extinction and LTP. The GR antagonist RU-38486 also prevented the CMS-induced alterations in extinction and plasticity, and when co-administered with WIN55,212-2, the preventive effects after CMS were maintained. The findings suggest that enhancing cannabinoid signaling could represent a novel approach to the treatment of cognitive deficits that accompany stress-related depression. 相似文献
73.
The human P2Y11 nucleotide receptor mRNA was found in virtually all human tissues, and the receptor serves many physiological roles, such as immune response regulation. The Ala-87-Thr-P2Y11 receptor single nucleotide polymorphism was linked to increased risk for acute myocardial infarction. To facilitate the development of new therapeutic applications involving cells expressing several P2 receptor subtypes, the availability of specific and potent agonists is mandatory. Here, we synthesized a series of novel adenine nucleotide derivatives, based upon the potent P2Y11 receptor agonists AR-C67085. Features of the novel nucleotide derivatives are a propylthio substitution at C2-adenine and a Pα-borano or Pα-thio substitution of non-bridging oxygen atom. The latter substitutions introduce a chiral center at the α-phosphate. Sp-isomers of Pα-borano- and Rp-isomers of Pα-thio-substituted nucleotides are preferred by the P2Y11 receptor. As recently reported by us, diastereoselectivity of the P2Y11 receptor is opposite to that of the P2Y1 receptor. Therefore, we exploit this characteristic to increase nucleotide selectivity. At the P2Y11 receptor, the Sp-isomers of 2-propylthio-ATP-α-B (2B) and 2-propylthio-ATP-α-B,β-γ-dichloromethylene (4B) were the most potent of the novel nucleotide series, with EC50 values of 0.03 μM for both, being ca. 80-fold more potent than 2-propylthio-ATP and ATP (EC50 = 2.6 μM). We conclude that the borano-substitution at the α-phosphate of 2-propylthio-ATP enhances nucleotide potency at the P2Y11 receptor. The combination with a Pβ-Pγ-dichloromethylene group in 4B results in a nucleotide, which shows higher selectivity for the P2Y11 receptor over the P2Y1 receptor than 2B making it the most promising of the novel P2Y11 receptor agonists. 相似文献
74.
R. A. Montgomery S. Katznelson W. I. Bry A. A. Zachary J. Houp J. M. Hiller S. Shridharani D. John A. L. Singer D. L. Segev 《American journal of transplantation》2008,8(10):2163-2168
Providing transplantation opportunities for patients with incompatible live donors through kidney paired donation (KPD) is seen as one of the important strategies for easing the crisis in organ availability. It has been estimated that an additional 1000—2000 transplants per year could be accomplished if a national KPD program were implemented in the United States. While most of these transplants could be arranged within the participants' local or regional area, patients with hard‐to‐match blood types or broad HLA sensitization would benefit from matching across larger geographic areas. In this case, either patients or organs would need to travel in order to obtain maximum benefit from a national program. In this study, we describe how a triple KPD enabled a highly sensitized patient (PRA 96%) to receive a well‐matched kidney from a live donor on the opposite coast. The kidney was removed in San Francisco and transported to Baltimore where it was reperfused 8 h later. The patient had prompt function and 1 year later has a serum creatinine of 1.1 mg/dl. This case provides a blueprint for solving some of the complexities that are inherent in the implementation of a national KPD program in a large country like the United States. 相似文献
75.
76.
Julyan H.E. Cartwright Nicolas Piro Oreste Piro Idan Tuval 《Developmental dynamics》2008,237(12):3477-3490
The manner in which the nodal flow determines the breaking of left–right symmetry during development is a beautiful example of the application of fluid dynamics to developmental biology. Detailed understanding of this crucial developmental process has greatly advanced by the transfer of ideas between these two disciplines. In this article, we review our and others' work on applying fluid dynamics and dynamical systems to the problem of left–right symmetry breaking in vertebrates. Developmental Dynamics 237:3477–3490, 2008. © 2008 Wiley‐Liss, Inc. 相似文献
77.
The Interleukin 1 (IL-1) family plays a central role in the generation and regulation of inflammatory responses, in both innate and adaptive immunity. Although the IL-1 molecules are traditionally considered to be classical proinflammatory cytokines, their functions are not restricted to inflammation, and they have also been shown to play a key role in a wide range of additional physiological and pathological functions, including learning modulation, sleep, pregnancy, depression, appetite, hematopoiesis, metabolism, and many others. Since their effect as cytokines and regulators of inflammation is so pleiotropic, any shift of the biological balance between agonistic and antagonistic signals has the potential to cause disease. Here, we consider the genetic influence of interleukin-1 gene polymorphism in the context of susceptibility to human diseases. We review known single nucleotide polymorphisms (SNP) of IL-1 genes linked to human diseases, and suggest how exploring biological effects of IL-1 gene cluster polymorphism may lead to new directions in understanding and diagnostic of disease and effective treatment. 相似文献
78.
David A. Axelrod Nino Dzebisashvili Mark A. Schnitzler Paolo R. Salvalaggio Dorry L. Segev Sommer E. Gentry Janet Tuttle-Newhall Krista L. Lentine 《Clinical journal of the American Society of Nephrology》2010,5(12):2276-2288
Background and objectives: Variation in kidney transplant access across the United States may motivate relocation of patients with ability to travel to better-supplied areas.Design, setting, participants, & measurements: We examined national transplant registry and U.S. Census data for kidney transplant candidates listed in 1999 to 2009 with a reported residential zip code (n = 203,267). Cox''s regression was used to assess associations of socioeconomic status (SES), distance from residence to transplant center, and relocation to a different donation service area (DSA) with transplant access and outcomes.Results: Patients in the highest SES quartile had increased access to transplant compared with those with lowest SES, driven strongly by 76% higher likelihood of living donor transplantation (adjusted hazard ratio [aHR] 1.76, 95% confidence interval [CI] 1.70 to 1.83). Waitlist death was reduced in high compared with low SES candidates (aHR 0.86, 95% CI 0.84 to 0.89). High SES patients also experienced lower mortality after living and deceased donor transplant. Patients living farther from the transplant center had reduced access to deceased donor transplant and increased risk of post-transplant death. Inter-DSA travel was associated with a dramatic increase in deceased donor transplant access (HR 1.94, 95% CI 1.88 to 2.00) and was predicted by high SES, white race, and longer deceased-donor allograft waiting time in initial DSA.Conclusions: Ongoing disparities exist in kidney transplantation access and outcomes on the basis of geography and SES despite near-universal insurance coverage under Medicare. Inter-DSA travel improves access and is more common among high SES candidates.It has been nearly a decade since the Department of Health and Human Services issued the Final Rule regarding the operations of the Organ Procurement and Transplantation Network (OPTN), which directs the transplant community to reduce disparity in access to transplantation, to allocate organs over as wide of a geographic area possible, and to ensure that organs are allocated on the basis of medical necessity (1). Reflecting such directives, the kidney allocation algorithm has been adjusted to reduce the importance of HLA matching to improve access to transplantation for racial and ethnic minorities (2). However, with the exception of the recent revisions to the heart transplant allocation system (3), there have been no successful revisions to the current geographic boundaries of organ allocation.Current deceased donor allocation policy is based on a system in which kidneys are initially offered to transplant centers in the local geographic area of recovery (donation service area [DSA]) before sharing within 1 of 11 geographic United Network for Organ Sharing (UNOS) regions, which each include ≥1 DSAs. As a result of substantial differences in the ratio of organs recovered to waiting candidates, there is dramatic variation in average waiting times across the UNOS regions, ranging from <2 years to nearly 7 years (4–7).The role of socioeconomic status (SES) in determining access to transplantation services is complex because SES affects care throughout the transplant process (8,9). Patients with low SES often delay seeking medical care and lack access to specialty services, leading to delays in transplant referral, evaluation, and listing (10,11). Despite near-universal eligibility for Medicare coverage on the basis of ESRD provisions, insurance status continues to influence outcome and access to transplantation. For example, kidney transplant candidates with Medicare-only health insurance were recently shown to have a 78% lower likelihood of being pre-emptively listed for transplant compared with privately insured patients, thereby increasing waiting list morbidity and reducing post-transplant graft survival (12). Conversely, patients with college (odds ratio 1.20, P < 0.001) or postgraduate education (odd ratio 1.65, P < 0.001) were significantly more likely to be listed before dialysis.The study presented here examined the associations of SES, distance from an individual''s residence to the transplant center (quantified as travel time), and choosing to travel to a different DSA with kidney transplant access and outcomes in the United States. Specifically, we examined the differential effects of these sociodemographic factors among listed candidates and recipients of live and deceased donor organs. We sought to understand the potential contributions of SES, geographic differences in place of residence, and individual relocation behaviors to current disparities in transplant access and outcomes. 相似文献
79.
Neocortical layer 5 (L5) pyramidal cells have at least two spike initiation zones: Na(+) spikes are generated near the soma, and Ca(2+) spikes at the apical dendritic tuft. These spikes interact with each other and serve as signals for synaptic plasticity. The present computational study explores the implications of having two spike-timing-dependent plasticity (STDP) signals in a neuron, each with its respective regional population of synaptic "pupils." In a detailed model of an L5 pyramidal neuron, competition emerges between synapses belonging to different regions, on top of the competition among synapses within each region, which characterizes the STDP mechanism. Interregional competition results in strengthening of one group of synapses, which ultimately dominates cell firing, at the expense of weakening synapses in other regions. This novel type of competition is inherent to dendrites with multiple regional signals for Hebbian plasticity. Surprisingly, such interregional competition exists even in a simplified model of two identical coupled compartments. We find that in a model of an L5 pyramidal cell, the different synaptic subpopulations "live in peace" when the induction of Ca(2+) spikes requires the back-propagating action potential (BPAP). Thus we suggest a new key role for the BPAP, to maintain the balance between synaptic efficacies throughout the dendritic tree, thereby sustaining the functional integrity of the entire neuron. 相似文献
80.
L. M. Kucirka C. Alexander R. Namuyinga C. Hanrahan R. A. Montgomery D. L. Segev 《American journal of transplantation》2009,9(3):620-628
The use of Public Health Service/Centers for Disease Control and Prevention (PHS/CDC) high-risk donor (HRD) organs remains controversial, especially in light of a recent high-profile case of human immunodeficiency virus (HIV) and hepatitis C virus (HCV) transmission. Nucleic acid testing (NAT), while more expensive and time consuming, reduces infectious risk by shortening the period between infection and detectability. The purpose of this study was to characterize HRDs and disposition of their organs by organ procurement organization (OPO), to measure NAT practices by OPO and to examine associations between NAT practices and use of HRD organs. We analyzed 29 950 deceased donors (2574 HRDs) reported to UNOS since July 1, 2004 and May 8, 2008. We then surveyed all OPO clinical directors about their use of NAT, average time to receive NAT results, locations where NAT is performed and percentage of the time NAT results are available for allocation decisions. In total, 51.7% of OPOs always perform HIV NAT, while 24.1% never do. A similar pattern is seen for HCV NAT performance, while the majority (65.6%) never perform HBV NAT. AIDS prevalence in an OPO service area is not associated with NAT practice. OPOs that perform HIV NAT are less likely to export organs outside of their region. The wide variation of current practice and the possibility that NAT would improve organ utilization support consideration for a national policy. 相似文献