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141.
We measured serum sex hormone-binding globulin (SHBG), total testosterone (T), non-SHBG-bound T, albumin-bound T, free T, and SHBG-bound T in 19 prepubertal boys with hypopituitarism. Serum SHBG decreased with age with a slope similar to that in 91 normal prepubertal boys at higher level, and therefore, it reached similar values at a later age. Serum SHBG was significantly higher in hypopituitary prepubertal boys [mean, 123 +/- 12 (+/- SE) nmol/L] than in normal prepubertal boys (76 +/- 4; P less than 0.001) despite the fact that their mean age was also higher (10.0 +/- 4 vs. 7.1 +/- 4.1 yr; P less than 0.001). In 4 boys with isolated hypogonadotropic hypogonadism (Kallman's syndrome), aged 15.6 +/- 1.5 yr, serum SHBG was 21 +/- 14 nmol/L, a value below the 95% confidence limit of the regression line in GH-deficient boys. The affinity constants of association of the SHBG-DHT complex were similar in hypopituitary and normal boys. Eleven of the 19 hypopituitary boys (mean chronological age, 8.3 +/- 2.5 yr; mean bone age, 4.1 +/- 2.1 yr) were treated with recombinant hGH (0.5 U/kg BW.week) for 1 yr. Their mean serum SHBG level before treatment was 154 +/- 14 nmol/L, and it decreased gradually to 106 +/- 5 nmol/L (P less than 0.01) after 12 months of treatment. The tendency toward normalization of serum SHBG during treatment suggested that GH deficiency was responsible for the high serum SHBG levels. Serum SHBG correlated negatively with age in both treated hypopituitary and normal boys, but the slope of the regression line was significantly steeper in treated hypopituitary boys (P less than 0.01). On the other hand, the mean serum non-SHBG-bound T level was 0.10 +/- 0.02 (+/- SE) nmol/L in hypopituitary boys, significantly lower than that in normal boys (0.21 +/- 0.02 nmol/L; P less than 0.02). Since serum total T concentrations were similar in the two groups, the higher serum SHBG concentration resulted in lower serum bioavailable T levels in the hypopituitary boys. These changes might explain the poor response to T treatment reported in GH-deficient patients. The lower serum non-SHBG-bound T concentrations in the GH-deficient boys suggest there may be delayed exposure of central nervous system structures to increased levels of sex hormones, which, in turn, may slow body maturation. This mechanism might play a role in the delay of puberty that occurs in patients with isolated GH deficiency.  相似文献   
142.
Chemokines are thought to control lymphocyte recruitment to the inflamed endothelium. To dissect chemokine-mediated adhesion, binding of ex vivo isolated splenocytes to tumor necrosis factor (TNF)-activated endothelial cells was analyzed under shear stress. We observed specific adhesion of naive follicular B cells, which could be blocked by pertussis toxin. This indicated a G protein-mediated binding and pointed at a contribution of chemokine receptors to B-cell adhesion. Analysis of chemokines expressed by TNF-activated endothelial cells showed that CC chemokine ligand 2 (CCL2), CCL17, and CCL20 were up-regulated. Only on follicular B cells was the cognate receptor for CCL20, CC chemokine receptor 6 (CCR6), expressed strongly, and a functional transmigration assay with CCR6-negative B cells demonstrated conclusively the sole signaling of CCL20 through CCR6. Desensitization of CCR6 on naive B cells with CCL20 resulted in receptor down-regulation and reduced B-cell adhesion. We conclude that CCL20 plays a vital role in B-cell adhesion to the inflamed endothelium.  相似文献   
143.
Untreated idiopathic congenital central hypoventilation syndrome (CCHS) is thought to cause infant death within 1-2 months. Here we present an adult patient with CCHS who survived without continuous ventilatory support, despite hypoventilation from early childhood onward. The diagnosis was confirmed at the age of 22 years, when the patient presented with hypoventilation during the night (PaCO2 60 mm Hg, PaO2 56 mm Hg, pH 7.32 HCO3- 30 mmol/l) but hyperventilation when awake (PaCO2 26 mm Hg, PaO2 81 mm Hg, pH 7.56, HCO3- 23 mmol/l). The maximal hematocrit was 77%. Despite mental retardation, noninvasive positive pressure ventilation (NPPV) could be successfully established. NPPV-supported ventilation during the night (PaCO2 36, PaO2 84 mm Hg, pH 7.47, HCO3- 25 mmol/l) reduced hematocrit values (40.6 to 36.8%) over a period of 4 years. In conclusion, long-term survival with CCHS is possible without continuous ventilatory support. Spontaneous improvement of hypoventilation during sleep throughout childhood is possible and hyperventilation during wakefulness may occur in patients with CCHS. CCHS can be managed with NPPV despite mental retardation, even over a long-term period.  相似文献   
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There is a growing interest in complementary medical practices, but few studies have investigated mechanisms behind the possible benefits. The effects of the homeopathic preparation Engystol on interferon-γ producing T-lymphocytes were studied in vitro. Lymphocytes were isolated from 30 healthy human volunteers and the percentage of interferon-γ producing cells was analysed by fluorescence activated cell sorting. Cells were treated with NaCl (control) or Engystol at concentrations from undiluted to 2%. All concentrations of Engystol increased the percentage of interferon-γ producing lymphocytes significantly, from a mean of 20.9% ± 10.5% to over 24%. There was no dose‐dependence of the effect at the concentrations tested.  相似文献   
146.
European Journal of Clinical Microbiology & Infectious Diseases - During an epidemic period, we compared patients hospitalized for initial suspicion of COVID-19 but for whom an alternative...  相似文献   
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Survivin (BIRC5) is an acknowledged cancer therapy‐resistance factor and overexpressed in head and neck squamous cell carcinomas (HNSCC). Driven by its nuclear export signal (NES), Survivin shuttles between the nucleus and the cytoplasm, and is detectable in both cellular compartments in tumor biopsies. Although predominantly nuclear Survivin is considered a favorable prognostic disease marker for HNSCC patients, the underlying molecular mechanisms are not resolved. Hence, we performed immunohistochemical and mutational analyses using laser capture microdissection on HNSCC biopsies from patients displaying high levels of nuclear Survivin. We found somatic BIRC5 mutations, c.278T>C (p.Phe93Ser), c.292C>T (p.Leu98Phe), and c.288A>G (silent), in tumor cells, but not in corresponding normal tissues. Comprehensive functional characterization of the Survivin mutants by ectopic expression and microinjection experiments revealed that p.Phe93Ser, but not p.Leu98Phe inactivated Survivin's NES, resulted in a predominantly nuclear protein, and attenuated Survivin's dual cytoprotective activity against chemoradiation‐induced apoptosis. Notably, in xenotransplantation studies, HNSCC cells containing the p.Phe93Ser mutation responded significantly better to cisplatin‐based chemotherapy. Collectively, our results underline the disease relevance of Survivin's nucleocytoplasmic transport, and provide first evidence that genetic inactivation of Survivin's NES may account for predominantly nuclear Survivin and increased therapy response in cancer patients.  相似文献   
150.
Correction for ‘Tantalum(v) 1,3-propanediolate β-diketonate solution as a precursor to sol–gel derived, metal oxide thin films’ by Christopher Beale et al., RSC Adv., 2020, 10, 13737–13748, DOI: 10.1039/D0RA02558E.

The authors regret that the plasma treatment and printing parameters were reported incorrectly in the subsection “Deposition on a-SiO2 for UV/Vis spectrophotometry” in the Experimental section of the original article.Before printing, the substrate for both samples was subjected to an argon plasma treatment for 5 minutes (150 W, 0.6 mbar). The plasma power is now corrected to be the same as stated in the “Deposition on a-SiO2 for Raman/XRD” subsection, where originally it was incorrectly stated that “the power was set slightly higher” for the Raman/XRD samples. For both the acetylacetone and benzoylacetone inks, the inks were printed on their respective substrates with a 75 μm drop pitch having dimensions of 400 × 220 drops to create a uniform layer.The correct section is as follows:  相似文献   
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