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Platelet α-granules release growth factors (GFs) that promote healing and tissue regeneration. Platelet-rich plasma (PRP) is shown to be beneficial in treating alopecia, and however, clinical response can be inconsistent. Due to several fold enrichment of platelets secreting large quantities of GFs following PRP injections, heterogeneity in amounts of GFs secreted by platelets may contribute to inconsistent clinical responses. Herein, we evaluated factors that could potentially contribute to heterogeneous secretion of GFs by platelets. We measured platelet secretion of transforming growth factor beta1 (TGFβ1), platelet-derived growth factor (PDGF-BB), epidermal growth factor (EGF), vascular endothelial growth factor (VEGF) and fibroblast growth factor (FGF2) in aliquots of de-identified PRP samples from female patients undergoing therapy in the hair disease clinic. Although secretion of GFs by platelets was comparable in PRP samples of patients with non-cicatricial and cicatricial alopecia, a Shapiro-Wilk test for normal distribution indicated significant variability across all patient samples. The amount of GF secreted by platelets was comparable when PRP prepared from two FDA-cleared devices with distinct techniques were compared. We provide evidence of platelets secreting heterogeneous amounts of GFs within each sample as high and low secretion of random factors could be simultaneously detected. These results suggest inherent heterogeneity in secretion of GFs by platelets in patient samples that are not influenced by the device used to prepare PRP. Since some GFs could have antagonistic effects on hair growth, a balance between amounts of growth promoting and inhibiting factors may be crucial in determining clinical response to PRP therapy.  相似文献   
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目的研究高原地区,脱髓鞘疾病与中老年人疾病等因素的关系。方法对我院所有接受过磁共振头部扫描的病人进行评估,确诊出40位脱髓鞘疾病患者,并对大脑7个部位的脱髓鞘疾病按严重性分4级打分,统计临床数据,最后运用统计学方法分析其相关性。结果在40例患者中,出现在大脑半球、放射冠、半卵圆中心和脑室前后角的脑白质损伤频率最多,分别占总量的50%、67.5%、77.5%和87.5%。脑白质损伤患者的平均年龄为47.1岁,这比世界其他地区都有明显的提前。男性患者将近是女性患者的3倍(29∶11)。年龄、慢性高原红细胞增多症、收缩压、脑梗塞与脑白质损伤正相关(P<0.05)。结论对于高海拔地区,有效控制高原心血管疾病的发生对于减少颅脑脱髓鞘疾病的发生具有重要意义。  相似文献   
4.
Vaccine-associated paralytic poliomyelitis (VAPP) is a rare complication of oral polio vaccine. We describe a fatal case of VAPP in an 8-month-old boy with Major Histocompatibility Class II deficiency. The isolated poliovirus was a Sabin type 2-type 1 recombinant that showed 1.4% VP1 divergence from Sabin type 2.  相似文献   
5.
Pancreatic panniculitis occurs in up to three percent of all patients with pancreatic disease. This cutaneous eruption, as implied by the name, is almost exclusively encountered in the context of pancreatic disorders, such as pancreatitis or pancreatic carcinoma. We report three cases in which histopathologic examination demonstrated hallmarks of pancreatic panniculitis occurring in patients without any history or evidence of pancreatic disorder. These nonpancreatic pancreatic panniculitis eruptions might be underreported in the literature.  相似文献   
6.
Bullous pemphigoid is an autoimmune condition whereby the immune system forms antibodies that target the skin, resulting in the formation of blisters in a generalized and symmetric pattern. Localized bullous pemphigoid can occur in special circumstances. Here, we describe two patients that developed localized bullous pemphigoid in one lower extremity following orthopedic surgery. We propose that underlying edema following orthopedic surgery is a potential trigger for localized bullous pemphigoid.  相似文献   
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BackgroundSexual dysfunction is common among adults and takes a toll on quality of life for both men and women.AimTo determine whether higher levels of weekly cardiovascular exercise are protective against self-reported sexual dysfunction among men and women.MethodsWe conducted an international online, cross-sectional survey of physically active men and women between April and December 2016, assessing exercise activity categorized into sextiles of weekly metabolic equivalent-hours. Odds ratios (ORs) of sexual dysfunction for each activity sextile compared with the lowest sextile were calculated using multivariable logistic regression, controlling for age, body mass index, diabetes mellitus, tobacco/alcohol use, sport, and marital status.Main Outcome MeasuresFemale sexual dysfunction was defined as a score ≤26.55 on the Female Sexual Function Inventory and erectile dysfunction (ED) was defined as a score ≤21 on the Sexual Health Inventory for Men.Results3,906 men and 2,264 women (median age 41–45 and 31–35 years, respectively) met the inclusion criteria for the study. Men in sextiles 2–6 had reduced odds of ED compared with the reference sextile in adjusted analysis (Ptrend = .03), with an OR of 0.77 (95% CI = 0.61–0.97) for sextile 4 and 0.78 (95% CI = 0.62–0.99) for sextile 6, both statistically significant. Women in higher sextiles had a reduced adjusted OR of female sexual dysfunction (Ptrend = .02), which was significant in sextile 4 (OR = 0.70; 95% CI = 0.51–0.96). A similar pattern held true for orgasm dissatisfaction (Ptrend < .01) and arousal difficulty (Ptrend < .01) among women, with sextiles 4–6 reaching statistical significance in both.Clinical ImplicationsMen and women at risk for sexual dysfunction regardless of physical activity level may benefit by exercising more rigorously.Strengths & LimitationsStrengths include using a large international sample of participants with a wide range of physical activity levels. Limitations include the cross-sectional design, and results should be interpreted in context of the study population of physically active adults.ConclusionHigher cardiovascular exercise levels in physically active adults are inversely associated with ED by self-report in men and protective against female sexual dysfunction in women.Fergus KB, Gaither TW, Baradaran N, et al. Exercise Improves Self-Reported Sexual Function Among Physically Active Adults. J Sex Med 2019;16:1236–1245.  相似文献   
8.
Complex three-dimensional (3-D) heart structure is an important determinant of cardiac electrical and mechanical function. In this study, we set to develop a versatile tissue-engineered system that can promote important aspects of cardiac functional maturation and reproduce variations in myofiber directions present in native ventricular epicardium. We cultured neonatal rat cardiomyocytes within a 3-D hydrogel environment using microfabricated elastomeric molds with hexagonal posts. By varying individual post orientations along the directions derived from diffusion tensor magnetic resonance imaging (DTMRI) maps of human ventricle, we created large (2.5 × 2.5 cm2) 3-D cardiac tissue patches with cardiomyocyte alignment that replicated human epicardial fiber orientations. After 3 weeks of culture, the advanced structural and functional maturation of the engineered 3-D cardiac tissues compared to age-matched 2-D monolayers was evident from: 1) the presence of dense, aligned and electromechanically-coupled cardiomyocytes, quiescent fibroblasts, and interspersed capillary-like structures, 2) action potential propagation with near-adult conduction velocity and directional dependence on local cardiomyocyte orientation, and 3) robust formation of T-tubules aligned with Z-disks, co-localization of L-type Ca2+ channels and ryanodine receptors, and accelerated Ca2+ transient kinetics. This biomimetic tissue-engineered platform can enable systematic in vitro studies of cardiac structure–function relationships and promote the development of advanced tissue engineering strategies for cardiac repair and regeneration.  相似文献   
9.
Our study aimed to determine the number of couples with normal hemoglobin (Hb) electrophoresis and low-borderline hematological values, which may come up with a clinically critical status in their offspring. The number of couples at risk for severe α-thalassemia (α-thal) needed to be estimated before recommending genetic counseling and prenatal diagnosis (PND). During the past 14 years, from at least 7000 referrals, 754 couples were investigated for α-thal by direct mutation detection methods followed by reverse strip assay and α-globin gene sequencing for inconclusive cases. Detection of silent β-thalassemia (β-thal) mutations was done in suspected cases by complete β-globin gene sequencing. We were able to provide a molecular diagnosis in 87.3% (658/754) of couples. A total of 9.1% (60/658) may have a clinically significant hemoglobinopathy in their offspring. Significant conditions included hydrops fetalis (20.0%; 12/60), certain Hb H (β4) genotypes (78.3%; 47/60) and β-thal intermedia (β-TI) (1.7%; 1/60). The diagnostic flowchart for couples with microcytic hypochromic anemia in countries with a high prevalence of hemoglobinopathies should include α and β gene sequencing. As our results indicate, every nine out of 100 of these couples will face significant hemoglobinopathies and every two out of 100 can carry Hb Bart’s (γ4) hydrops fetalis in their pregnancies. For such cases, PND should be utilized to allow the carrier couples to decide whether or not to abort the fetus.  相似文献   
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We assessed the impact of intra- and postoperative RBC transfusion on postoperative morbidity and mortality in cranial surgery. A total of 8924 adult patients who underwent cranial surgery were identified in the 2006–2011 American College of Surgeons (ACS) National Surgical Quality Improvement Program (NSQIP) database. Patients undergoing a biopsy, radiosurgery, or outpatient surgery were excluded. Propensity scores were calculated according to demographic variables, comorbidities, and preoperative laboratory values. Patients who had received RBC transfusion were matched to those who did not, by propensity score, preoperative hematocrit level, and by length of surgery, as an indirect measure of potential intraoperative blood loss. Logistic regression was used to predict adverse postoperative outcomes. A total of 625 (7%) patients were transfused with one or more units of packed RBCs. Upon matching, preoperative hematocrit, length of surgery, and emergency status were no longer different between transfused and non-transfused patients. RBC transfusion was associated with prolonged length of hospitalization (OR 1.6, 95% CI 1.2–2.2), postoperative complications (OR 2.8, 95% CI 2.0–3.8), 30-day return to operation room (OR 2.0, 95% CI 1.3–3.2), and 30-day mortality (OR 4.3, 95% CI 2.4–7.6). RBC transfusion is associated with substantive postoperative morbidity and mortality in patients undergoing both elective and emergency cranial surgery. These results suggest judicious use of transfusion in cranial surgery, consideration of alternative means of blood conservation, or pre-operative restorative strategies in patients undergoing elective surgery, when possible.  相似文献   
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