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991.
Cytotoxic T lymphocytes (CTLs) and natural killer (NK) cells use the perforin/granzyme pathway as a major mechanism to kill pathogen-containing cells and tumor cells.(1,2) Dysregulation of this pathway results in several human diseases, such as hemophagocytic lymphohistiocytosis. Here we characterize the single-cell expression pattern of granzymes A and B in human lymphocytes using a flow cytometry-based assay. We demonstrate that most circulating CD56(+)8(-) NK cells, and approximately half of circulating CD8(+) T lymphocytes, coexpressed both granzymes A and B. In contrast, few circulating CD4(+) T lymphocytes expressed granzymes A or B. Activation of CD8(+) T lymphocytes with concanavalin A (ConA)/interleukin-2 (IL-2), and activation of CD4(+) T lymphocytes with antibodies to CD3/CD28 or CD3/CD46 (to generate T regulatory [Tr1] cells), induced substantial expression of granzyme B, but not granzyme A. Naive CD4(+)CD45RA(+) cells stimulated with antibodies to CD3/CD46 strongly expressed granzyme B, while CD3/CD28 stimulation was ineffective. Finally, we show that granzyme B-expressing CD4(+) Tr1 cells are capable of killing target cells in a perforin-dependent, but major histocompatibility complex (MHC)/T-cell receptor (TCR)-independent, manner. Our results demonstrate discordant expression of granzymes A and B in human lymphocyte subsets and T regulatory cells, which suggests that different granzymes may play unique roles in immune system responses and regulation.  相似文献   
992.
BACKGROUND DNA mutational analysis of pancreatic cystic fluid(CF) is a useful adjunct to the evaluation of pancreatic cysts. KRAS/GNAS or RAF/PTPRD/CTNNB1/RNF43 mutations are highly specific to precancerous or advanced neoplasia. Several studies recently demonstrated the ability of next-generation sequencing(NGS) analysis to detect DNA mutations in pancreatic CF, but few studies have performed a systematic comparative analysis between pancreatic CF and neoplastic surgical tissue(NT). The value of CF-NGS analysis indicators for determining surgical resection necessitates evaluation.AIM To confirm whether CF genomic profiles are a reliable malignancy predictor by comparing NGS mutational analyses of CF and NT.METHODS Patients requiring surgery for high-risk pancreatic cysts were included in a multicenter prospective pilot study. DNA from CF(collected by endoscopic ultrasound-guided fine needle aspiration(known as EUS-FNA)) and NT(collected by surgery) were analyzed by NGS. The primary objective was to compare the mutation profiles of paired DNA samples. The secondary objective was to correlate the presence of specific mutations(KRAS/GNAS, RAF/PTPRD/CTNNB1/RNF43/POLD1/TP53) with a final cancer diagnosis.Sensitivity and specificity were also evaluated.RESULTS Between December 2016 and October 2017, 20 patients were included in this pilot study. Surgery was delayed for 3 patients. Concordant CF-NT genotypes were found in 15/17 paired DNA, with a higher proportion of mutated alleles in CF than in NT. NGS was possible for all pancreatic CF collected by EUS-FNA. In 2 cases, the presence of a KRAS/GNAS mutation was discordant between CF and NT. No mutations were found in 3 patients with NT or pancreatic cysts with high-grade dysplasia. The sensitivity and specificity of KRAS/GNAS mutations in CF to predict an appropriate indication for surgical resection were 0.78 and 0.62, respectively. The sensitivity and specificity of RAF/PTPRD/CTNNB1/RNF43/POLD1/TP53 mutations in CF were 0.55 and 1.0, respectively.CONCLUSION Mutational analyses of CF and NT were highly concordant, confirming the value of NGS analysis of CF in the preoperative malignancy assessment. However,these results need to be confirmed on a larger scale.  相似文献   
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ABSTRACT

The authors evaluated the feasibility of a 1-hour session to ensure competency in gait and falls risk assessment for medical students at their institution. The session included a history and exam with faculty and staff as standardized patients, gait recognition videos, and case evaluation for falls risk assessment and prevention. Student perceptions were evaluated using a retrospective pre–post survey, scored on a 5-point Likert-type scale. Wilcoxon signed-rank tests were used to assess change and Kruskal–Wallis tests were used to analyze differences by residency choice. A range of five to 11 faculty and staff certified 238 medical students during eight 1-hour sessions. Overall self-perception of competence in falls risk assessment and prevention improved (p ≤ .001), and did not differ by residency choice, both before and after the training program (p = .73 and p = .25). Feedback was positive. This session is a feasible way to teach and assess the competency for falls risk assessment with modest time commitment.  相似文献   
997.
Type 1 diabetes (T1D) is considered a disorder whose pathogenesis is autoimmune in origin, a notion drawn in large part from studies of human pancreata performed as far back as the 1960s. While studies of the genetics, epidemiology, and peripheral immunity in T1D have been subject to widespread analysis over the ensuing decades, efforts to understand the disorder through analysis of human pancreata have been far more limited. We have reviewed the published literature pertaining to the pathology of the human pancreas throughout all stages in the natural history of T1D. This effort uncovered a series of findings that challenge many dogmas ascribed to T1D and revealed data suggesting the marked heterogeneity in terms of its pathology. An improved understanding and appreciation for pancreatic pathology in T1D could lead to improved disease classification, an understanding of why the disorder occurs, and better therapies for disease prevention and management.  相似文献   
998.
Recent disappointing results of clinical trials seeking type 1 diabetes (T1D) reversal suggest the need for a reevaluation of our translational efforts. This Commentary explores the need for standards in evaluating therapeutic efficacy in preclinical models of T1D.  相似文献   
999.
OBJECTIVETo review surgical results of endoscopic transthoracic limited sympathotomy for palmar-plantar hyperhidrosis during the past decade.PATIENTS AND METHODSWe retrospectively reviewed 155 consecutive patients who underwent surgery from June 30, 2000, through December 31, 2009, for medically refractory palmar-plantar hyperhidrosis using a technique of T1-T2 sympathotomy disconnection, designed for successful palmar response and minimization of complications.RESULTSOf the 155 patients, 44 (28.4%) were male, and 111 (71.6%) were female; operative times averaged 38 minutes. No patient experienced Horner syndrome, intercostal neuralgia, or pneumothorax. The only surgical complication was hemothorax in 2 patients (1.3%); in 1 patient, it occurred immediately postoperatively and in the other patient, 10 days postoperatively; treatment in both patients was successful. All 155 patients had successful (warm and dry) palmar responses at discharge. Long-term follow-up (>3 months; mean, 40.2 months) was obtained for 148 patients (95.5%) with the following responses to surgery: 96.6% of patients experienced successful control of palmar sweating; 69.2% of patients experienced decreased axillary sweating; and 39.8% of patients experienced decreased plantar sweating. At follow-up, 5 patients had palmar sweating (3 patients, <3 months; 1 patient, 10-12 months; 1 patient, 16-18 months). Compensatory hyperhidrosis did not occur in 47 patients (31.7%); it was mild in 92 patients (62.2%), moderate in 7 patients (4.7%), and severe in 2 patients (1.3%).CONCLUSIONIn this series, a small-diameter uniportal approach has eliminated intercostal neuralgia. Selecting a T1-T2 sympathotomy yields an excellent palmar response, with a very low severe compensatory hyperhidrosis complication rate. The low failure rate was noted during 18 months of follow-up and suggests that longer follow-up is necessary in these patients.  相似文献   
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Individuals reporting chronic, nonmalignant pain for at least 6 months (N = 114) were randomly assigned to 8 weekly group sessions of acceptance and commitment therapy (ACT) or cognitive-behavioral therapy (CBT) after a 4-6 week pretreatment period and were assessed after treatment and at 6-month follow-up. The protocols were designed for use in a primary care rather than specialty pain clinic setting. All participants remained stable on other pain and mood treatments over the course of the intervention. ACT participants improved on pain interference, depression, and pain-related anxiety; there were no significant differences in improvement between the treatment conditions on any outcome variables. Although there were no differences in attrition between the groups, ACT participants who completed treatment reported significantly higher levels of satisfaction than did CBT participants. These findings suggest that ACT is an effective and acceptable adjunct intervention for patients with chronic pain.  相似文献   
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