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【摘要】 报道临床症状不典型的家族性黑棘皮病1家系。先证者女,4岁,自1周岁时,颈部、腹部出现黑色斑片,近年来逐渐扩大至唇周、躯干前部。腹部皮肤全反式共聚焦显微镜检查可见乳头环下延扭曲及沟壑结构,乳头环内可见中高折光颗粒结构。先证者父亲及祖母既往有类似病史,但随着年龄增长色素沉着自发性消退,仅有局部皮纹增粗。采集先证者及父母、祖母外周血,对先证者外周血DNA行Panel靶向测序,结果显示,先证者存在FGFR3基因14号外显子c.1949A>C(p.Lys650Thr)错义突变,Sanger测序验证证实先证者及其父亲和祖母均存在此突变。诊断:家族性黑棘皮病。 相似文献
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《Vaccine》2020,38(31):4783-4791
A novel coronavirus (CoV), Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), emerged in late 2019 in Wuhan, China and has since spread as a global pandemic. Safe and effective vaccines are thus urgently needed to reduce the significant morbidity and mortality of Coronavirus Disease 2019 (COVID-19) disease and ease the major economic impact. There has been an unprecedented rapid response by vaccine developers with now over one hundred vaccine candidates in development and at least six having reached clinical trials. However, a major challenge during rapid development is to avoid safety issues both by thoughtful vaccine design and by thorough evaluation in a timely manner. A syndrome of “disease enhancement” has been reported in the past for a few viral vaccines where those immunized suffered increased severity or death when they later encountered the virus or were found to have an increased frequency of infection. Animal models allowed scientists to determine the underlying mechanism for the former in the case of Respiratory syncytial virus (RSV) vaccine and have been utilized to design and screen new RSV vaccine candidates. Because some Middle East respiratory syndrome (MERS) and SARS-CoV-1 vaccines have shown evidence of disease enhancement in some animal models, this is a particular concern for SARS-CoV-2 vaccines. To address this challenge, the Coalition for Epidemic Preparedness Innovations (CEPI) and the Brighton Collaboration (BC) Safety Platform for Emergency vACcines (SPEAC) convened a scientific working meeting on March 12 and 13, 2020 of experts in the field of vaccine immunology and coronaviruses to consider what vaccine designs could reduce safety concerns and how animal models and immunological assessments in early clinical trials can help to assess the risk. This report summarizes the evidence presented and provides considerations for safety assessment of COVID-19 vaccine candidates in accelerated vaccine development. 相似文献
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BackgroundThe pattern of epochal evolution of NoV is ongoing, while novel GII.4 variants emerge and cause new pandemics. Since, the emergence in March 2012, Sydney_2012 had replaced GII.4-2009 as the primary NoV strain in most countries in the northern hemisphere by November 2012.ObjectivesTo determine the genotype distribution around the emergence of Sydney_2012 and to investigate the underlying evolution mechanisms of the contemporary GII.4 strains.Study designFrom January 2012 to December 2013, molecular epidemiology of norovirus in 846 adults (≥16 years) in Shanghai were conducted. The VP1 proteins of the contemporary GII.4 strains (Den_Haag_2006b, New_Orleans_2009 and Sydney_2012) were expressed in vitro and purified. Receptor binding patterns of these three epidemic strains were determined through histo-blood group antigen (HBGA) binding assays. Convalescent serum from patients infected with GII.4 epidemic strains were employed to investigate the role of antigenic drift in the persistence of GII.4 epidemic strains through receptor-binding blockade assays.ResultsEpidemiological studies revealed that Sydeny_2012 has completely replaced Den_Haag_2006b and New_Orleans_2009 and has been the dominant circulating strain in Shanghai since its emergence in October 2012. Interestingly, Den_Haag_2006b and New_Orleans_2009 have been co-circulating in Shanghai before the emergence of Sydeny_2012. The contemporary GII.4 epidemic norovirus strains displayed commonly high tropism to the histo-blood group antigen receptors, whereas Sydeny_2012 was antigenically different from Den_Haag_2006b and New_Orleans_2009.ConclusionsAntigenic drift, rather than receptor switch, played a key role in the emergence and spreading of Sydney_2012. The contemporary GII.4 strains were evolving via epochal evolution without altered ligand binding profiles. 相似文献
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《The journal of sexual medicine》2020,17(4):614-622
BackgroundAlthough abnormal sympathetic nerve system (SNS) activity has been demonstrated in the pathogenesis of ejaculation disorders, few data are available on its underlying mechanism.AimTo investigate whether differences in ejaculatory behavior of rats were associated with the state of SNS activity and gamma-aminobutyric (GABA) receptor expressions in the paraventricular nucleus (PVN) of the hypothalamus and the effects of GABA receptors in the PVN on ejaculatory behavior.MethodsBased on ejaculatory performance, Sprague-Dawley rats were divided into “sluggish,” “normal,” and “rapid” ejaculators. PVN microinjection was performed to evaluate the role of GABA receptors on sexual behavior.OutcomesThe outcomes include differences in expression and distribution of GABA receptors and norepinephrine level among the 3 groups and changes in copulation behavior parameters after PVN microinjection.ResultsCompared with “normal” rats, the “rapid” group ejaculated more times with shorter latency (P < .001, P < .001) and had lower expression and distribution of both GABA-A and GABA-B receptors, while the opposed results appeared in the “sluggish” group. The norepinephrine level was successively increased among “sluggish,” “normal,” and “rapid” rats (P < .001) and correlated with ejaculation frequency (r = 0.896, P < .001) and ejaculation latency (r = −0.835, P < .001). In addition, bilateral microinjection of the GABA-A and GABA-B receptor agonist (isoguvacine and baclofen) into the PVN both significantly prolonged the intromission latency and inhibited ejaculation, which could be blocked by antagonist gabazine and CGP-35348, respectively. Vigabatrin, the GABA-transaminase inhibitor, caused a significantly reduced ejaculation frequency and extended ejaculation latency in rats, which could be offset by simultaneous injections of gabazine and CGP-35348.Clinical ImplicationsOur findings provide new understanding about GABA receptors in the PVN on sexual behavior and enhance the comprehension of neurobiological mechanisms involved in premature ejaculation.Strengths & LimitationsOur results have indicated that GABA receptors in the PVN may inhibit ejaculation through restraining the activity of SNS. However, our study did not analyze the changes of GABA receptors in other brain areas, which needs further study.ConclusionEjaculation behaviors in male rats are associated with SNS activity and could be regulated by GABA receptors in the PVN, which may be of assistance in the treatment of ejaculation disorders in the future.Zhang QJ, Yang BB, Yang J, et al. Inhibitory Role of Gamma-Aminobutyric Receptors in Paraventricular Nucleus on Ejaculatory Responses in Rats. J Sex Med 2020;17:614–622. 相似文献
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《The journal of sexual medicine》2020,17(7):1280-1287
BackgroundHigh salt intake is a risk factor for hypertension, which can potentially lead to erectile dysfunction (ED); however, the underlying pathological mechanisms remain unclear.AimTo investigate whether erectile function is directly impaired by high salt intake and whether selective inhibition of mineralocorticoid receptor (MR) could provide protection from ED.Methods6-week-old male Dahl salt-sensitive rats were randomly divided into 3 groups: normal diet (0.3% NaCl; control, n = 8), high-salt diet (8% NaCl; HS, n = 8), and high-salt diet plus eplerenone (HS + EPL, n = 11). HS + EPL rats were orally administered daily doses of EPL (75 mg/kg) for 6 weeks; control and HS rats received purified water on the same schedule.OutcomesAt the end of the study period, erectile function was evaluated by measuring intracavernosal pressure and mean arterial pressure after cavernous nerve stimulation. Serum levels of asymmetric dimethylarginine and L-arginine were determined using ultraperformance liquid chromatography–tandem mass spectrometry. Quantitative PCR was used to assess the expression of MR, inflammation, and oxidative stress markers (nicotinamide adenine dinucleotide phosphate oxidase-1/4, p22phox, interleukin-6, and superoxide dismutase-1), and protein arginine N-methyltransferase-1.ResultsThe intracavernosal pressure/mean arterial pressure ratio was significantly lower, whereas systolic blood pressure, MR expression, serum asymmetric dimethylarginine levels, oxidative stress, and levels of inflammatory biomarkers were significantly higher in HS rats than in control rats (P < .05). EPL administration significantly improved each of these parameters except systolic blood pressure and MR expression. No significant intergroup differences were observed for L-arginine and superoxide dismutase-1 levels.Clinical TranslationOur results provide a rationale for the need of salt restriction and the use of selective MR inhibitors in prophylaxis or treatment of ED in men consuming a high-salt diet.Strengths & LimitationsWe are the first to report that the adverse impact of high salt intake on erectile function is mediated via MR activation, independent of its effect on blood pressure. A major limitation of this study is that responses of salt-resistant rats were not studied.ConclusionsHigh salt intake directly impaired erectile function in Dahl salt-sensitive rats, whereas selective MR inhibition ameliorated this effect.Kishimoto T, Kataoka T, Yamamoto Y, et al. High Salt Intake Impairs Erectile Function in Salt-Sensitive Rats Through Mineralocorticoid Receptor Pathway Beyond Its Effect on Blood Pressure. J Sex Med 2020;17:1280–1287. 相似文献
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PurposeThe impact of the adherence to dietary guidelines of early-stage breast cancer (EBC) patients on body composition changes during treatment is not entirely defined. This study aimed to evaluate the role of an evidence-based nutrition educational intervention, according to adherence to dietary guidelines, in EBC patients.MethodsThis prospective study included EBC patients, candidates for neoadjuvant/adjuvant therapy. Patients received an evidence-based tailored nutrition educational intervention. The adherence to dietary guidelines, anthropometric and dietary assessments, and blood glucose and lipid profile tests were evaluated at baseline and after a 12-months nutritional intervention.ResultsTwo hundred and forty-three patients were enrolled. At baseline, 38.3% and 23.9% of patients were overweight and obese, weight gain ≥5% (compared to 6-months before enrollment) and central obesity were observed in 47.3% and 52.7% of patients, respectively. Adherence to dietary guidelines was low (median Med-Diet score: 6 [IQR 4–8]). After the nutritional intervention (median follow-up: 22 months [range 12–45]), adherence to dietary guidelines significantly increased (median Med-Diet score: 12 [IQR 8–13]), p < 0.0001). High adherence to dietary guidelines (defines as Med-Diet score ≥10) significantly correlated with: 1) overall weight loss ≥5% (21.8% vs. 2.5%, p = 0.003); 2) median BMI drop (from 25.6 kg/m2 to 24.4 kg/m2, p = 0.003); 3) lower prevalence of central obesity (38.2% vs. 7.2%, p = 0.01); 4) improvement in blood glucose levels and lipid profile.ConclusionThis study suggests that an evidence-based tailored nutrition educational intervention during treatment for EBC significantly increases overall adherence to dietary guidelines, and it improves both anthropometric measures and serum metabolic biomarkers in patients with high adherence. 相似文献