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51.
52.
Surgical management of parapharyngeal space tumors: a 10-year review.   总被引:8,自引:0,他引:8  
OBJECTIVE: The purpose of this article is to describe the diagnostic evaluation and surgical approaches to parapharyngeal space tumors in a tertiary referral center. STUDY DESIGN AND SETTING: The study is a retrospective review of 47 patients diagnosed with tumors of the parapharyngeal space (12 with malignant diseases and 35 with benign lesions) and surgically treated during a 10-year period. The transcervical (40%) and the transcervical-transparotid approaches (46%) were the most commonly performed surgical procedures followed by the orbitozygomatic-middle fossa approach (12%) and the transmandibular approach (2%). RESULTS: The surgical procedures were uneventful and there were no postoperative mortalities. Complications were rare; the most common was transient facial nerve paralysis (5 patients). After an average follow-up of 35 months, only 1 of 35 patients with benign diseases had a recurrence 5 years following transcervical resection of a pleomorphic adenoma. Of 12 patients with malignant tumors, 5 (42%) are alive with no evidence of disease. The sensitivity of preoperative fine needle aspiration biopsy (n = 23 patients) was 87% for detection of malignant disease and specificity was 100%. CONCLUSIONS: Most benign parapharyngeal space tumors can be removed surgically with a low rate of complications and recurrence. Malignant neoplasms, however, carry an ominous prognosis and a low rate of disease-free survival. Fine needle aspiration may be helpful in preoperative diagnostic evaluation of patients with parapharyngeal space tumors.  相似文献   
53.
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   
54.
Abstract

Background: 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   
55.
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   
56.
    
When considering advocacy of split-liver transplantation, it is important to understand whether comparable outcomes can be achieved. The goal of this study was to identify donor and transplant characteristics predictive of comparable outcomes by risk factor analysis. Using the United Network for Organ Sharing/ Organ Procurement and Transplantation Network data base between January 1996 and May 2006, first time adult/child split cases (568 adults, 508 children) were examined. In multivariate analysis, recipient medical condition (hospitalization), status 1 assignment, ABO incompatibility, donor age (>40 years), donor body weight (≤40 kg), calculated whole graft volume to recipient body weight ratio (cGRWR ≤1.5%) and no sharing between centers were significant risk factors in adult recipients.
Recipient diagnosis of tumor, dialysis prior to transplant, recipient body weight (≤6 kg), donor age (>30 years), donor history of cardiac arrest after declaration of death and cold ischemia time (CIT > 6 h) increased the risk of graft failure in pediatric recipients. The livers from young donors showed comparable outcomes to whole deceased liver transplantation (LT) when other transplant-related risk factors were minimized in adult recipients. Reducing CIT is important to obtain comparable outcomes to living donor LT in pediatric recipients.  相似文献   
57.
    
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   
58.
    
Human immunodeficiency virus (HIV) is no longer a contraindication to transplantation. For HIV‐infected patients, HIV‐infected deceased donors (HIVDD) could attenuate the organ shortage and waitlist mortality. However, this practice would violate United States federal law. The goal of this study was to estimate the potential impact of legalizing transplantation of HIV‐infected organs by quantifying the potential pool of HIVDD. Using Nationwide Inpatient Sample (NIS) data, HIV‐infected deaths compatible with donation were enumerated. Using HIV Research Network (HIVRN) data, CD4 count, plasma HIV‐1 RNA level, AIDS‐defining illnesses and causes of death were examined in potential HIVDD. Using UNOS data, evaluated donors who later demonstrated unanticipated HIV infections were studied. From NIS, a yearly average of 534 (range: 481–652) potential HIVDD were identified, with 63 (range: 39–90) kidney‐only, 221 (range: 182–255) liver‐only and 250 (range: 182–342) multiorgan donors. From HIVRN, a yearly average of 494 (range: 441–533) potential HIVDD were identified. Additionally, a yearly average of 20 (range: 11–34) donors with unanticipated HIV infection were identified from UNOS. Deceased HIV‐infected patients represent a potential of approximately 500–600 donors per year for HIV‐infected transplant candidates. In the current era of HIV management, a legal ban on the use of these organs seems unwarranted and likely harmful.  相似文献   
59.
    
Kidney transplant and liver transplant are the treatments of choice for patients with end‐stage renal disease and end‐stage liver disease, respectively. Pancreas transplant is most commonly performed along with kidney transplant in diabetic end‐stage renal disease patients. Despite a steady increase in the numbers of kidney and liver transplants performed each year in the United States, a significant shortage of kidneys and livers available for transplant remains. Organ allocation is the process the Organ Procurement and Transplantation Network (OPTN) uses to determine which candidates are offered which deceased donor organs. OPTN is charged with ensuring the effectiveness, efficiency and equity of organ sharing in the national system of organ allocation. The policy has changed incrementally over time in efforts to optimize allocation to meet these often competing goals. This review describes the history, current status and future direction of policies regarding the allocation of abdominal organs for transplant, namely the kidney, liver and pancreas, in the United States.  相似文献   
60.
    
Kidney transplant education is associated with higher transplantation rates; however national policies regarding optimal timing and content of transplant education are lacking. We aimed to characterize nephrologists’ attitudes regarding kidney transplant education, and to compare practices between nephrologists at for-profit and nonprofit centers. We surveyed 906 nephrologist practicing in the United States. Most respondents (81%) felt the ideal time to spend on transplant education was >20 min, but only 43% reported actually doing so. Spending >20 min was associated with covering more topics, having one-on-one and repeated conversations, involving families in discussions and initiating discussions at CKD-stage 4. Providers at for-profit centers were significantly less likely to spend >20 min (RR = 0.89, 95%CI: 0.80–0.99) or involve families (RR = 0.57, 95%CI: 0.38–0.87); they reported that fewer of their patients received transplant counseling (RR = 0.58, 95%CI: 0.37–0.96), initiated transplant discussions (RR = 0.58, 95%CI: 0.38–0.88), or were eligible for transplantation (RR = 0.45, 95%CI: 0.30–0.68). Of nephrologists who spent ≤20 min, those at for-profit centers more often cited lack of reimbursement as a reason (30.0% vs. 18.9%, p = 0.02). Disparities in quality of education at for-profit centers might partially explain previously documented disparities in access to transplantation for patients at these centers. National policies detailing the optimal timing and content of transplant education are needed to improve equity.  相似文献   
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