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1.
In a patient with azoospermia secondary to bilateral agenesis of the vas deferens an artificial spermatocele was constructed from the tunica vaginalis testis. The sperm reservoir has been in place for 14 years with its size and the quality of the aspirated semen unchanged. A total of 70 aspirations performed during this period yielded mean volumes of 0.7 +/- 0.24 ml. with a sperm density of 60 +/- 14.7 million per ml. Sperm morphology was normal and sperm motility, although markedly decreased, responded well to stimulation by a motility enhancer. The patient did not have antisperm antibodies.  相似文献   
2.
Cranial computed tomography (CCT) findings for 37 patients with cycloid psychosis and 19 patients with DSM-III-R schizophrenia were compared with findings for age- and sex-matched controls. Schizophrenic patients showed enlarged ventricles compared both to controls and to patients suffering from cycloid psychosis. In patients with cycloid psychosis, neither at the first episode nor after many years (mean 16.6 years) of disease were significant differences found compared to control subjects. Over the course of the illness, patients with cycloid psychosis showed ventricular enlargement which was correlated with age but not with the duration of illness. The morphological differences provide further evidence for the proposed nosological distinction between cycloid psychosis and schizophrenia.  相似文献   
3.
In this report we detail a procedure for the cloning of a rat encephalitogenic T cell line and show that the methods normally employed for other species may not always be applicable. The two important differences to be described are, (i) that in these experiments where the parent T cell lines were generated with thymocytes as presenting cells, splenocytes were not suitable as a source of antigen-presenting or stimulator cells and (ii) semipurified forms of IL-2, specifically that derived from EL4 lymphoma cells, resulted in a much reduced cloning frequency and rate of T cell growth compared with cruder mixtures such as that derived from mitogen-stimulated splenocytes. Functional studies with clones derived from a strongly encephalitogenic (experimental autoimmune encephalomyelitis (EAE)-inducing) T cell line revealed that the clones had a reduced capacity to mediate EAE in recipient rats but were otherwise comparable to the parent line in terms of surface phenotype and fine antigen specificity. In an attempt to begin to identify the type of CD4+ T cells that may induce EAE we tested the clones and lines for secreted interferon-gamma by a sensitive ELISA, and showed that all clones secreted high levels of this factor.  相似文献   
4.
Primary myeloid sarcoma of the testicle with t(15;17)   总被引:1,自引:0,他引:1  
The first case of acute promyelocytic leukemia presenting as a solitary testicular mass (myeloid sarcoma) that relapsed in the contralateral testicle is described. The neoplastic cells strongly expressed chloroacetate esterase, myeloperoxidase, CD33, CD43, and weakly, CD117. The presence of many azurophil granules and Auer rods was detected by electron microscopy. Translocation (15;17)(q22;q21.1) was revealed by cytogenetics and was verified by fluorescence in situ hybridization. Contralateral testicle is a favorite site for recurrence in a subset of testicular myeloid sarcomas. Subclassification of all cases of myeloid sarcoma ought to be attempted.  相似文献   
5.
Seven of 15 gastrointestinal stromal tumors from the author's file were classified as plexosarcomas when examined by electron microscopy and immunohistochemistry. Electron microscopy was essential for the diagnosis.  相似文献   
6.

Background and aims

Growth differentiation factor 15 (GDF15) is a strong predictor of cardiovascular morbidity and mortality found to be both marker and target of impaired glucose metabolism. GDF15 increases following glucose administration and is up-regulated in obesity and diabetes. We investigate here the relationship between GDF15 and beta cell function.

Methods and results

In this cross-sectional study we evaluated GDF15 concentrations in 160 obese subjects (BMI 35–63 kg/m2, age 39.4 ± 18.6 years, m/f 38/122) who underwent a 75 g oral glucose tolerance test (OGTT). Based on the OGTT results, the cohort was divided into two groups: 1) normal fasting glucose and normal glucose tolerance (n = 80), 2) impaired fasting glucose, impaired glucose tolerance or type 2 diabetes (n = 80). The relationship of GDF15 to fasting and OGTT-based dynamic insulin sensitivity and insulin secretion parameters was evaluated.GDF15 was higher in the prediabetes and diabetes groups and correlated with HbA1c, glucose, insulin as well as baseline and dynamic indices of insulin sensitivity and estimated beta cell function. Multiple regression analysis revealed that age, waist-to-height ratio, glomerular filtration rate and prehepatic beta cell function, but not the grade of impairment of glucose metabolism, were independent predictors of GDF15. Subgroup analysis showed that of all parameters of glucose metabolism only C-peptide, fasting prehepatic beta cell function and insulinogenic index remained significantly related to GDF15 in both groups.

Conclusion

We conclude that in patients with severe obesity, GDF15 strongly relates to beta cell function and should be further investigated as a potential therapeutic target and biomarker guiding treatment options.  相似文献   
7.
Pregnancy presents a unique physiological challenge that requires changes coordinated by placentally and non–placentally derived hormones to prepare the mother for the metabolic stress presented by fetal development and to ensure appropriate nutrient allocation between mother and fetus. Of particular importance is the maintenance of normal glucose metabolism during pregnancy. Here, we describe physiological changes in glucose metabolism during pregnancy and highlight new insights into these adaptations that have emerged over the past decade using novel methodologies, specifically genome-wide association studies (GWAS) and metabolomics. While GWAS have identified some novel associations with metabolic traits during pregnancy, the majority of the findings overlap with those observed in nonpregnant populations and individuals with type 2 diabetes (T2D). Metabolomics studies have provided new insight into key metabolites involved in gestational diabetes mellitus (GDM). Both of these approaches have suggested that a strong link exists between GDM and T2D. Most recently, a role of the gut microbiome in pregnancy has been observed, with changes in the microbiome during the third trimester having metabolic consequences for the mother. In this Perspectives in Diabetes article, we highlight how these new data have broadened our understanding of gestational metabolism, and emphasize the importance of future studies to elucidate differences between GDM and T2D.  相似文献   
8.
Obesity is associated with a chronic low-grade inflammation characterized by macrophage infiltration of adipose tissue (AT) that may underlie the development of insulin resistance and type 2 diabetes. Osteopontin (OPN) is a multifunctional protein involved in various inflammatory processes, cell migration, and tissue remodeling. Because these processes occur in the AT of obese patients, we studied in detail the regulation of OPN expression in human and murine obesity. The study included 20 morbidly obese patients and 20 age- and sex-matched control subjects, as well as two models (diet-induced and genetic) of murine obesity. In high-fat diet-induced and genetically obese mice, OPN expression was drastically up-regulated in AT (40 and 80-fold, respectively) but remained largely unaltered in liver (<2-fold). Moreover, OPN plasma concentrations remained unchanged in both murine models of obesity, suggesting a particular local but not systemic importance for OPN. OPN expression was strongly elevated also in the AT of obese patients compared with lean subjects in both omental and sc AT. In addition, we detected three OPN isoforms to be expressed in human AT and, strikingly, an obesity induced alteration of the OPN isoform expression pattern. Analysis of AT cellular fractions revealed that OPN is exceptionally highly expressed in AT macrophages in humans and mice. Moreover, OPN expression in AT macrophages was strongly up-regulated by obesity. In conclusion, our data point toward a specific local role of OPN in obese AT. Therefore, OPN could be a critical regulator in obesity induced AT inflammation and insulin resistance.  相似文献   
9.
Sleeve Gastrectomy and Gastric Banding: Effects on Plasma Ghrelin Levels   总被引:17,自引:1,他引:16  
Background: Different changes of plasma ghrelin levels have been reported following gastric banding, Roux-en-Y gastric bypass, and biliopancreatic diversion. Methods: This prospective study compares plasma ghrelin levels and weight loss following laparoscopic sleeve gastrectomy (LSG) and laparoscopic adjustable gastric banding (LAGB) in 20 patients. Results: Patients who underwent LSG (n=10) showed a significant decrease of plasma ghrelin at day 1 compared to preoperative values (35.8 ± 12.3 fmol/ml vs 109.6 ± 32.6 fmol/ml, P=0.005). Plasma ghrelin remained low and stable at 1 and 6 months postoperatively. In contrast, no change of plasma ghrelin at day 1 (71.8 ± 35.3 fmol/ml vs 73.7 ± 24.8 fmol/ml, P=0.441) was found in patients after LAGB (n=10). Increased plasma ghrelin levels compared with the preoperative levels at 1 (101.9 ± 30.3 fmol/ml vs 73.7 ± 24.8 fmol/ml, P=0.028) and 6 months (104.9 ± 51.1 fmol/ml vs 73.7 ± 24.8 fmol/ml, P=0.012) after surgery were observed. Mean excess weight loss was higher in the LSG group at 1 (30 ± 13% vs 17 ± 7%, P=0.005) and 6 months (61 ± 16% vs 29 ± 11%, P=0.001) compared with the LAGB group. Conclusions: As a consequence of resection of the gastric fundus, the predominant area of human ghrelin production, ghrelin is significantly reduced after LSG but not after LAGB. This reduction remains stable at follow-up 6 months postoperatively, which may contribute to the superior weight loss when compared with LAGB.  相似文献   
10.
Obesity is a chronic disease with a worldwide increasing incidence. The mainstay of therapy consists in modification of behaviour related to obesity such as overeating and physical inactivity. When these life-style modifying attempts fail, the use of anti-obesity drugs is warranted. Public health efforts and current anti-obesity agents have not controlled the increasing epidemic of obesity, which has led to an extensive research on novel anti-obesity agents. This review presents an overview on potential future candidates.  相似文献   
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