Ancestry reported by white adults with cutaneous melanoma and control subjects in central Alabama

Background  

We sought to evaluate the hypothesis that the high incidence of cutaneous melanoma in white persons in central Alabama is associated with a predominance of Irish and Scots descent.     

Renal proximal tubular cell growth and differentiation are differentially modulated by renotropic growth factors and tyrosine kinase inhibitors

BACKGROUND: The renotropic growth factors (GFs), hepatocyte GF (HGF), epidermal GF (EGF), and insulin-like GF-I (IGF-I) accelerate renal regeneration in animal models after toxic or ischemic injury. These GFs initiate their biological effects on renal tubular cells by interaction with specific transmembrane receptor tyrosine kinases. MATERIALS AND METHODS: In the proximal tubular cell line PT-1, the biological effects of HGF, EGF, and IGF-I and the growth-inhibitory effects of different tyrosine kinase inhibitors (TKIs) were investigated. Receptor binding and tyrosine kinase phosphorylation were determined by ligand binding studies and Western blot analysis. RESULTS: HGF, EGF, and IGF-I bound with nanomolar affinity to their specific cell membrane receptor tyrosine kinases. In contrast to EGF or IGF-I, HGF induced a variety of cell morphological changes, including cell scattering, formation of tubular structures, and expression of long microvilli on the apical cell membrane. HGF was a 10-fold more potent and more effective growth promoter than EGF or IGF-I. Among the TKIs tested, the mitogenic effect of HGF could be more specifically inhibited by emodin and tyrphostin, that of EGF by methyl-2,5-dihydroxycinnamate, lavendustin A, and genistein, and that of IGF-I by geldanamycin. CONCLUSIONS: In contrast to EGF and IGF-I, HGF stimulated both growth and differentiation of renal proximal tubular cells, demonstrating the amazing biological potency of this renotropic growth factor. Selective TKIs may be a promising approach to modulate diseases with abnormalities in protein kinase signalling pathways such as renal cell carcinoma.     

Longitudinal evaluation of serum estradiol and estrone in male patients infected with the human immunodeficiency virus

In patients with human immunodeficiency virus (HIV) infection alteration of various endocrine functions have been described. However, there is limited information available on estrogens and their function in these patients. The aim of this study was to evaluate the pituitary and testicular endocrine markers: 14 HIV-positive men were included into the longitudinal study with a follow up to of 18 month period. None of the patients had a history or clinical evidence of endocrine dysfunction. Follicle stimulating hormone (FSH), luteinizing hormone (LH), prolactin, estrone, estradiol, and testosterone were measured in serum by commercially available radioimmunoassays. Prolactin levels were not affected in the patients. LH and FSH remained within normal range, but at the end of the study period we observed a significant increase of LH (p < 0.05). In addition, testosterone levels were normal with a slight reduction at the end of the 18-month observation period (p <0.05). Both estrone and estradiol were significantly increased with a further rise at the end of the study (p <0.05). In summary, the elevation of the serum estrone and estradiol in HIV-afflicted patients correlated with the progress of the HIV-disease, being paralleled by a decrease in testosterone. The altered relation of estrogens and testosterone may in a part be responsible for the complaints of decreased libido and increased impotence often observed in HIV-infected men.     

Enzymatic activation of autotaxin by divalent cations without EF-hand loop region involvement

Autotaxin (ATX) is a recently described member of the nucleotide pyrophosphatase/phosphodiesterase (NPP) family of proteins with potent tumor cell motility-stimulating activity. Like other NPPs, ATX is a glycoprotein with peptide sequences homologous to the catalytic site of bovine intestinal alkaline phosphodiesterase (PDE) and the loop region of an EF-hand motif. The PDE active site of ATX has been associated with the motility-stimulating activity of ATX. In this study, we examined the roles of the EF-hand loop region and of divalent cations on the enzymatic activities of ATX. Ca(2+) or Mg(2+) was each demonstrated to increase the PDE activity of ATX in a concentration-dependent manner, whereas incubation of ATX with chelating agents abolished this activity, indicating a requirement for divalent cations. Non-linear regression analysis of enzyme kinetic data indicated that addition of these divalent cations increases reaction velocity predominantly through an effect on V(max.) Three mutant proteins, Ala(740)-, Ala(742)-, and Ala(751)-ATX, in the EF-hand loop region of ATX had enzymatic activity comparable to that of the wild-type protein. A deletion mutation of the entire loop region resulted in slightly reduced PDE activity but normal motility-stimulating activity. However, the PDE activity of this same deletion mutant remained sensitive to augmentation by cations, strongly implying that cations exert their effect by interactions outside of the EF-hand loop region.     

魔芋精粉的降血糖作用

目的：研究魔芋精粉的降糖作用。方法：以不同剂量魔芋精粉ｉｇ正常小鼠和四氧嘧啶糖尿病小鼠,连续１０ｄ后,葡萄糖氧化酶法测定正常小鼠的空腹血糖、糖耐量试验以及四氧嘧 啶糖尿病小鼠的血糖尿病小鼠的血糖,以放射免疫法测定血清胰岛素。结果：魔芋精粉有降低正常小鼠血糖作用,呈一定量效关系趋势;且具有改善小鼠糖耐量作用,能明显降低四氧嘧啶糖尿病小鼠血糖,但因清胰岛素水平无明显影响。结论：魔芋精粉可能是通过影响糖代     

Suspected poisoning in children. Study of the incidence of true poisoning and poisoning scare in a defined population in North East Bristol

The distinction between true and suspected poisoning in children has not been made clear in previous work on childhood poisoning. A study of suspected poisoning in children under 15 years of age in a defined population of North East Bristol from November 1970 to July 1973 carried out by the Health Education Council Medical Research Division included 53,000 child-years at risk. The number of suspected poisonings was 3-4/1000 population aged under 15 years per year, with a higher incidence in younger age groups. Detailed investigation of the circumstances of the accidents carried out by a multidisciplinary team showed that at least 65%, and possibly as many as 78% were poisoning scares and not true poisoning. The evidence used by the casualty doctor and by the parents to diagnose poisoning was explored, and in many cases was circumstantial. Children with fathers in nonmanual occupations were over-represented. This may reflect differences in patterns of utilization behaviour rather than true differences in incidence.     

Dysphagia as the Sole Manifestation of Bilateral Strokes

Dysphagia can be caused by a host of factors, most of which are structural or functional. However, despite extensive evaluations, a certain number of patients have unexplained dysphagia. We present an extremely unusual case whereby a patient with an acute left hemispheric cerebral vascular accident presents with dysphagia as his sole complaint and after extensive neurological, gastroenterological, and radiographic examinations is found to have cricopharyngeal dysfunction. The etiology of this defect was not at all clinically apparent and, ultimately, magnetic resonance imaging (MRI) was performed which revealed a chronic infarction of the right frontal lobe and a smaller acute infarction in the same location of the left. This case demonstrates that swallowing disorders may be the sole presentation of stroke and that, if extensive evaluations of such patients fail to yield an etiology, one must strongly consider MRI as a tool for diagnosis, even if a CT scan is negative.     

Accuracy of dual-energy radiographic absorptiometry of the lumbar spine: cadaver study

Dual-energy radiographic absorptiometry (DRA) was used to measure the bone mineral content and area density of lumbar vertebrae (L2-L3) in 11 cadavers. These data were subsequently compared with measured ash content and density. Excellent correlation was obtained between bone mineral content measured with DRA and ash weight (r = .963, P less than .0001). The accuracy error in determining mineral content in lumbar vertebrae with DRA was about 9%. In addition, strong correlation was observed between bone mineral density measured with DRA and ash density (r = .881, P less than .0001).