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31.
Epidermal growth factor receptor (EGFR) is a transmembrane glycoprotein with tyrosine-kinase signaling activity, involved in many cellular functions including cell growth and differentiation. Germ line loss-of-function mutations in EGFR lead to a severe neonatal skin disorder (Online Mendelian Inheritance in Man #131550). We report 18 premature Roma children from 16 families with birthweights ranging 440–1470 g and multisystem diseases due to the homozygous mutation c.1283G˃A (p.Gly428Asp) in EGFR. They presented with thin, translucent, fragile skin (14/15), skin desquamation (10/17), ichthyosis (9/17), recurrent skin infections and sepsis (9/12), nephromegaly (10/16) and congenital heart defects (7/17). Their prognosis was poor, and all died before the age of 6 months except one 13-year-old boy with a severe skin disorder, dentinogenesis imperfecta, Fanconi-like syndrome and secondary hyperaldosteronism. Management of ion and water imbalances and extremely demanding skin care may improve the unfavorable outcome of such patients.  相似文献   
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The hearing abilities of a group of 30 elderly (67-93 yr of age) subjects were compared with those of a group of 30 young (19-27 yr of age) normal hearing volunteers with the aim of characterizing the changes in the peripheral and central parts of the auditory system. In elderly subjects the pure-tone thresholds were typically represented by a gradually sloping curve with a significantly greater decline in men than in women at frequencies of 3 and 4 kHz. In spite of pure tone threshold elevation in the elderly, the difference limen for intensity at 1 and 3 kHz were not significantly smaller than in the young subjects. The incidence and levels of spontaneous, transient and distortion product otoacoustic emissions were low, which would suggest the involvement of outer hair cell pathology. Also, contralateral suppression was less marked in elderly than in young subjects. Speech audiometry in the elderly revealed serious difficulties in understanding speech. Deteriorated temporal resolution, as demonstrated by increased gap detection thresholds, correlated significantly with increased speech recognition thresholds. The results support the view that presbycusis represents a combination of deteriorated function of the auditory periphery with deteriorated function of the central auditory system.  相似文献   
34.
Waist circumference (WC) may be the best anthropometric index for identifying individuals at risk for cardiovascular disease (CVD) and diabetes mellitus (DM). The objectives of this study were to determine if the relationship between WC and metabolic risk factors is similar in men and women of Chinese and European descent, and to assess the effect of ethnicity on these relationships. Apparently healthy men and women of Chinese (n = 92) and European (n = 99) descent were recruited from hospital staff and assessed for anthropometric variables and blood pressure (BP), lipids, insulin, and glucose. The study cohort was stratified by sex, and regression analyses were performed with the various metabolic risk factors as the outcome and WC and ethnicity as predictors. Chinese men and women had significantly lower WC than European men and women. Age and metabolic risk factors were similar between the 2 ethnic groups except for BP. Metabolic risk factors significantly correlated with WC within each gender and ethnic cohort. In men, ethnicity was an independent predictor for total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), triglycerides (TG), and the ratio of TC to high-density lipoprotein cholesterol (HDL-C) after controlling for WC. In women, ethnicity significantly interacted with WC as an independent predictor of TG, TC:HDL-C ratio, insulin, and glucose. As ethnic descent modifies the relationship between WC and metabolic risk factors, current WC targets derived from relationships in European populations are not applicable to Chinese men and women. Therefore, ethnic background should be considered when using WC as a marker of cardiovascular risk.  相似文献   
35.
OBJECTIVES: This study sought to identify whether obesity and obstructive sleep apnea (OSA) independently predict incident atrial fibrillation/flutter (AF). BACKGROUND: Obesity is a risk factor for AF, and OSA is highly prevalent in obesity. Obstructive sleep apnea is associated with AF, but it is unknown whether OSA predicts new-onset AF independently of obesity. METHODS: We conducted a retrospective cohort study of 3,542 Olmsted County adults without past or current AF who were referred for an initial diagnostic polysomnogram from 1987 to 2003. New-onset AF was assessed and confirmed by electrocardiography during a mean follow-up of 4.7 years. RESULTS: Incident AF occurred in 133 subjects (cumulative probability 14%, 95% confidence interval [CI] 9% to 19%). Univariate predictors of AF were age, male gender, hypertension, coronary artery disease, heart failure, smoking, body mass index, OSA (hazard ratio 2.18, 95% CI 1.34 to 3.54) and multiple measures of OSA severity. In subjects <65 years old, independent predictors of incident AF were age, male gender, coronary artery disease, body mass index (per 1 kg/m2, hazard ratio 1.07, 95% CI 1.05 to 1.10), and the decrease in nocturnal oxygen saturation (per 0.5 U log change, hazard ratio 3.29, 95% CI 1.35 to 8.04). Heart failure, but neither obesity nor OSA, predicted incident AF in subjects > or =65 years of age. CONCLUSIONS: Obesity and the magnitude of nocturnal oxygen desaturation, which is an important pathophysiological consequence of OSA, are independent risk factors for incident AF in individuals <65 years of age.  相似文献   
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This study was undertaken to resolve existing controversies with respect to the detection of IgA HIV-1-specific mucosal antibodies in infected individuals. External secretions, including tears, nasal, rectal, and vaginal washes, saliva, semen, urine, and sera were obtained from 50 HIV-1-infected individuals and 20 controls using collection procedures that minimize the irritation of mucosal surfaces. Levels of total and antigen (gp120 and gp160)-specific antibodies of the IgG and IgA isotypes were measured by assays that proved reliable in a large multicenter study: quantitative ELISA and chemiluminescence-enhanced Western blot analyses. Although the levels of total IgG and IgA were increased or remained unchanged in body fluids of HIV-1-infected individuals as compared to the controls, HIV-1-specific IgA antibodies were either absent or present at low levels even in secretions with characteristically high relative contents of total IgA vs. IgG (saliva, tears, and rectal and nasal washes). In these secretions, HIV-1-specific IgG antibodies dominated. In assessing levels and frequency of detection of IgG antibodies, both female and male genital tract secretions, urine, and nasal wash were preferable to parotid saliva and especially to rectal wash. External secretions contained IgG antibodies to gp160> gp120> gp41 and p24; when present, IgA antibodies were predominantly directed at gp160. Analyses of peripheral blood antibody-secreting cells (ASC) isolated from the same individuals paralleled these serological findings: gp160-specific IgG-secreting ASC were dominant. Therefore, in striking contrast to other mucosally encountered microbial infections, HIV-1 does not induce vigorous specific IgA responses in any body fluid examined or in ASC in peripheral blood.  相似文献   
38.

Background

The Heartmate 3 (HM3) is a Conformiteé Européenne mark–approved left ventricular (LV) assist device (LVAD) with fully magnetically levitated rotor and features consisting of a wide range operational speeds, wide flow paths, and artificial pulse. We performed a hemodynamic-echocardiographic speed optimization evaluation in HM3-implanted patients to achieve optimal LV- and right ventricular (RV) shape.

Methods and Results

Sixteen HM3 patients underwent pump speed ramp tests with right heart catheterization. Three-dimensional echocardiographic (3DE) LV and RV datasets (Philips) were acquired, and volumetric (Tomtec) and shape (custom software) analyses were performed (LV: sphericity, conicity; RV: septal and free-wall curvatures). Data were recorded at up to 13 speed settings. Speed changes were in 100-rpm steps, starting at 4600 rpm and ramping up to 6200 rpm. 3DE was feasible in 50% of the patients. Mean original speed was 5306 ± 148 rpm. LV end-diastolic (ED) diameter (?0.15 ± 0.09 cm/100 rpm) and volumes (ED: 269 ± 109 mL to 175 ± 90 mL; end-systolic [ES]: 234 ± 111 mL to 146 ± 81 mL) progressively decreased as the shape became less spherical and more conical; RV volumes initially remained stable, but at higher speeds increased (ED: from 148 ± 64 mL to 181 ± 92 mL; ES: 113 ± 63 mL to 130 ± 69 mL). On average, the RV septum became less convex (bulging toward the LV) at the highest speeds.

Conclusions

LV and RV shape changes were noted in HM3-supported patients. Although a LV volumetric decrease and shape improvement was consistently noted, RV volumes grew in response to increase in speed above a certain point. A next concern would be whether understanding of morphologic and function changes in LV and RV during LVAD speed change assessed with the use of 3DE helps to optimize LVAD speed settings and improve clinical outcomes.  相似文献   
39.
BACKGROUND/AIMS: Acute mesenteric ischemia (AMI) is a serious disease in old age with low incidence but with a very high mortality rate (60-70%). The etiology is either primary (embolism or thrombosis of mesenteric arteries or veins, non-occlusive mesenteric ischemia) or secondary (mechanical obstruction such as intestinal volvulus, intussusception, tumor-caused compression). Independent of the origin of the illness, the clinical-pathological picture is the same: intestinal ischemia with subsequent necrosis. The aim of this study was to ascertain which underlying conditions lead to increased probability of development of acute mesenteric ischemia. METHODS: Two hundred and fifteen patients with a primary form of AMI were treated in the years 1991-2007, in the 1st Clinic of Surgery in Brno, Czech Republic and in the Department of General Surgery, Derer's University Hospital in Bratislava, Slovak Republic; the results of the treatment have been statistically evaluated. CONCLUSION: The probability of arterial mesenteric ischemia development rises significantly (p < 0.05) in patients with a history of atrial fibrillation and/or myocardial infarction. This probability is also significantly higher in smokers with symptoms of hypertension and clinical signs of abdominal angina (p < 0.05).  相似文献   
40.
Myeloid-derived suppressor cells are immature myeloid cells, consisting of a monocytic and a granulocytic fraction, that are known to suppress anti-tumor immune responses. Important targets of the immunosuppressive capacity of MDSC are CD8+ T cells, which are crucial cytotoxic effector cells in immunotherapeutic settings. CD8+ T-cell activation and differentiation comprises a well-orchestrated series of events, starting from early TCR-mediated signaling and leading to cytokine secretion, the expression of activation markers, proliferation and the differentiation into several subsets of effector and memory cells. In this review, we summarize the available data on how the production of reactive oxygen species, nitric oxide, the arginase-mediated depletion of l-arginine and Cystine depletion by MDSCs interfere with the signaling molecules necessary for normal CTL differentiation and activation.  相似文献   
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