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We used the species specificity and repetitious nature of subtelomeric kinetoplastida sequences to generate a duplex PCR assay for the simultaneous detection of Trypanosoma cruzi and Trypanosoma rangeli in experimentally and naturally infected triatomine (Reduviid) bugs and in infected human subjects. The assay was species specific and was capable of detecting 1/20th of T. cruzi and 1/4th of T. rangeli cell equivalents without complementary hybridization. In addition, the PCR-based assay was robust enough for direct application to difficult biological samples such as Reduviid feces or guts and was capable of recognizing all T. cruzi and T. rangeli strains and lineages. Because the assay primers amplify entirely different target sequences, no reaction interference was observed, facilitating future adaptation of this assay to an automated format.  相似文献   
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Myasthenia gravis (MG) is an autoimmune disease of the neuromuscular junction. Immunosuppressive treatments are part of the therapeutic armamentarium in MG. Long-term systemic steroid administration carry considerable risks and adverse events. Consequently, steroid-free immunosuppressive therapy is necessary to reduce the dose or discontinue steroids. First immunosuppressive drug trials in MG were performed in the mid-60s using standard and nonspecific immunosuppression. Since then, only few randomized controlled clinical trials were conducted in MG and assesed drug efficacy in terms of its steroid-sparing capacity and the ability to reduce myasthenic signs and symptoms. Treatment strategy in MG is quite challenging, mainly due to the disease heterogeneity in terms of clinical presentation, immunopathogenesis and drug response. To solve this dilemma, emerging treatment are based on biological drugs and use new targets of the immune pathway.  相似文献   
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Lateral left ventricular wall rupture (LVWR) is a rare complication following acute myocardial infarction (AMI) less than 1%. After cardiogenic shock, LVWR constitutes the most common cause of in‐hospital death in AMI patients. Around 40% of all LVWR occurred during the first 24 hours and 85% within the first week. In the present case, 76 hours following the intervention, LVWR was observed likely due to a small infarction at the lateral left ventricular wall possibly due to the marginal lesion. Our patient refused surgery and was followed clinically. Eighteen months later, real time three‐dimensional echocardiography showed a pseudoaneurysm.  相似文献   
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Context

There is limited literature regarding outpatient palliative care and factors associated with unscheduled clinic visits.

Objectives

To compare characteristics of patients with unscheduled vs. scheduled outpatient palliative care clinic visits.

Methods

Medical records of 183 unscheduled cancer new outpatients and 104 unscheduled follow-up (FU) patients were compared with random samples of 361 and 314 scheduled new patients and FU patients, respectively. We gathered data on demographics, symptoms, daily opioid usage, and performance status.

Results

Compared with scheduled new patients, unscheduled new patients had worse Edmonton Symptom Assessment Scale subscores for pain (P < 0.001), fatigue (P = 0.002), nausea (P = 0.016), depression (P = 0.003), anxiety (P = 0.038), drowsiness (P = 0.002), sleep (P < 0.001), and overall feeling of well-being (P = 0.001); had a higher morphine equivalent daily dose of opioids (median of 45 mg for unscheduled vs. 30 mg for scheduled; P < 0.001); and were more likely to be from outside the greater Houston area (P < 0.001). Most unscheduled and scheduled new and FU visits were for uncontrolled physical symptoms. Unscheduled FU patients, compared with scheduled FU patients, had worse Edmonton Symptom Assessment Scale subscores for pain (P < 0.001), fatigue (P < 0.001), depression (P = 0.002), anxiety (P = 0.004), drowsiness (P = 0.010), appetite (P = 0.023), sleep (P = 0.022), overall feeling of well-being (P < 0.001), and higher morphine equivalent daily dose of opioid (median of 58 mg for unscheduled FU visits vs. 40 mg for scheduled FU visits; P = 0.054).

Conclusion

Unscheduled new FU patients have higher levels of physical and psychosocial distress and higher opioid intake. Outpatient palliative care centers should consider providing opportunities for walk-in visits for timely management and close monitoring of such patients.  相似文献   
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Gastrointestinal carcinoid tumors arise from cells of the diffuse neuroendocrine system localized in the digestive trace and represent more than 70% of all carcinoid tumors in humans. The present article reviews the following topics: 1) The biological profile of these tumors (histopathology, cytokine markers, metabolic alterations, storage of neuroamines and hormonal proteins, cytodynamic behavior, and biological behavior according to embryological origin). 2) The etiological circumstances (exceptional hereditary factors, association of gastric carcinoid tumors with autoimmune gastritis, little-known exogenous factors). 3) Pathogenic aspects (persistent mitogenesis of endocrine cells associated with hypergastrinemia, inactivation of some putative tumor suppressor genes, the doubtful participation of oncogenes, autocrine action of some cellular growth-stimulating proteins). 4) The repercussions of certain physiopathological events (peritumoral desmoplastic reaction causing the "mass effect" on the digestive tube, the "kidnapping" of dietary tryptophan by tumoral cells toward an abnormal metabolic pathway; the easy metastatic dissemination coexisting with low tumoral aggressivity, and the release into the bloodstream of stored secretory products leading to "carcinoid syndrome" and some endocrine hyperfunction syndromes. Finally, it should be remembered that gastrointestinal carcinoid tumors represent only a proportion of the neoplasms classified as neuroendocrine tumors.  相似文献   
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IntroductionThe molecular mechanisms underlying alcoholic liver fibrosis and cirrhosis are not completely understood. Hepatic fibrosis involves the interplay of diverse cells and factors, including hepatic stellate cells (HSCs), Kupffer, NK cells, and T-lymphocyte subsets. Killer-cell immunoglobulin-like receptors (KIR) are membrane receptors involved in mediation between NK and activated HSCs, regulating NK cell function through their interaction with HLA-I molecules. The aim of this study was to analyse the genetic association between KIR genes and the susceptibility to or protection from alcoholic cirrhosis (AC) in a cohort of male AC patients undergoing liver transplantation (LT) with and without concomitant viral infections.Material and methodsKIR genotyping was performed in nuclear DNA extracted from 281 AC patients and compared with 319 male controls.ResultsSignificant differences between total AC patients and healthy controls were only found in the case of KIR2DL2 and KIR2DS5. KIR2DL2 was significantly underrepresented in non-viral AC patients (52.6% vs. 63.3%; p = 0.015), while patients heterozygous for KIR2DL2 were also underrepresented in the non-viral AC group compared with controls (p = 0.034). KIR2DS5 was overrepresented in this group compared with healthy controls (p = 0.002). All these observations were only evident in AC patients older than 54 years old.ConclusionsOur data suggest a contrary effect of KIR2DL2 and KIR2DS5 in AC patients older than 54 years, in whom the presence of KIR2DL2 appears to be protective against AC, whereas the presence of KIR2DS5 seems to promote the fibrotic process, particularly in patients with no associated viral infection.  相似文献   
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