Graphitization behavior of iodine-treated <Emphasis Type="Italic">Bombyx mori</Emphasis> silk fibroin fiber

In order to investigate the graphitization behavior of Bombyx mori silk fibroin (SF) fibers, structural inspection of carbonized SF fibers treated with iodine vapor was studied at different temperatures, from 800 to 1400 °C. Wide angle X-ray diffraction measurement suggested that both untreated and iodinated SF fibers exhibited amorphous structure carbonized to 1200 °C. After carbonization at 1400 °C for 12 h, a graphite-like structure was obtained. Raman spectroscopy and transmission electron microscopic observation showed that the graphite layers of SF fibers became more ordered after iodine treatment. The carbon yield obtained at higher temperature (1400 °C) after iodine treatment was higher, ca. 28 wt%, than that of untreated SF.     

Long-term efficacy of a self-retaining intraurethral catheter for the treatment of prostatic obstruction

The aim of the present study was to estimate insulin secretion, insulin sensitivity (SI), and glucose effectiveness at basal insulin (SG) in subjects with bulimia nervosa. Eight bulimic patients and eight age-, body mass index-, and sex-matched healthy control subjects without a family history of diabetes were studied. The subjects all had normal glucose tolerance. They underwent a modified frequently sampled intravenous glucose tolerance test; glucose (300 mg/kg body weight) was administered, and insulin (4 mU/kg body weight/min) was infused from 20 to 25 minutes after administration of glucose. SI and SG were estimated by Bergman's minimal model method. Basal insulin (27 +/- 3 v 45 +/- 3 pmol/L) was significantly lower in bulimic patients than in normal controls (P < .05), but basal glucose was similar between the two groups (4.5 +/- 0.1 v 4.9 +/- 0.1 mmol/L, P > .05). The glucose disappearance rate (KG) and acute insulin response to glucose estimated by the intravenous glucose tolerance test (AIR(glucose)) were similar between the two groups (KG, 1.35 +/- 0.29 v 2.20 +/- 0.21 min(-1), P > .05; AIR(glucose), 2,920 +/- 547 v 2,368 +/- 367 pmol/L x min, P > .05). No significant difference was observed in SI between the two groups (1.34 +/- 0.18 v 1.25 +/- 0.20 x 10(-4) x min(-1) x pmol/L(-1), P > .05). On the other hand, glucose effectiveness at basal (SG) and zero (GEZI) insulin was significantly diminished in comparison to normal controls (SG, 0.011 +/- 0.002 v 0.024 +/- 0.002 min(-1), P < .01; GEZI, 0.008 +/- 0.002 v 0.017 +/- 0.003 min(-1), P < .01). Thus, bulimic patients with normal glucose tolerance without a family history of diabetes were characterized by normal insulin secretion, normal SI, and reduced SG and GEZI.     

The prognostic significance of macroscopic growth pattern of hepatocellular carcinoma

AIM: To investigate the prevalence and amount of polyploidy in fine needle aspiration specimens of the liver, urinary cytospin preparations, and cytospin preparations from pleural and peritoneal fluid. METHODS: Cells from 44 liver smears, 48 urine specimens, and 46 pleural and peritoneal aspirations were examined. After Feulgen restaining the DNA content of 100 randomly selected nuclei was determined using a TAS-plus image analysis system, combined with an automated microscope. RESULTS: Polyploidy was observed up to 16c in the liver, and up to 8c in urothelium and mesothelium. Sixty eight per cent of the liver aspirates contained polyploid nuclei. The rate in urothelium was 20.8% and in mesothelium 6.5%. CONCLUSIONS: Polyploidy in the liver may be interpreted as being associated with tissue differentiation, but the findings in urothelium and mesothelium remain of unknown importance.     

Prostacyclin analog-suppressed ischemia-reperfusion injury of the rat liver: evaluation by calpain mu activation

Advances in perinatal and neonatal health care over the past few decades have resulted in a substantial reduction in perinatal mortality. Some of this improvement has been attributed to antepartum fetal surveillance techniques. The primary objective of antepartum fetal surveillance techniques is to avoid fetal deaths. An ideal secondary objective is to avoid neonatal complications related to intrauterine asphyxia. In this article, some of the difficulties in evaluating existing antepartum fetal surveillance techniques are highlighted. Some of the epidemiological methods for evaluating a screening test are reviewed and their importance discussed with reference to fetal testing procedures. Lastly, the possibility of considering indication-specific fetal testing to improve perinatal morbidity is examined.     

Bilateral peripelvic fat simulating renal pelvic tumor

Lipomas are benign tumors which may simulate peripelvic masses and usually originate in the renal cortex or the perirenal adipose tissue. Excessive proliferation of the peripelvic fat of the kidney simulating a renal pelvic tumor was detected in our case, illustrating a rare instance in which the kidney was salvaged.     

Detection of contamination of vaccines with the reticuloendotheliosis virus by reverse transcriptase polymerase chain reaction (RT-PCR)

Phospholipase C (phosphatidylcholine phosphohydrolase, EC 3.1.4.3) and lipase (EC 3.1.1.3) activities were detected in the supernatant fluid of Pseudomonas fluorescens strain D cultures. A combination of ultrafiltration and successive chromatography through columns of Sephadex G-75 and DEAE-cellulose was used to purify the phospholipase C over 700-fold from the culture medium, with 28.5% yield. The purified enzyme appeared as a single band after polyacrylamide gel electrophoresis. The apparent molecular mass of the phospholipase C was 36,000 daltons when estimated by gel permeation chromatography. The purified enzyme hydrolysed phosphatidylcholine more efficiently than phosphatidylethanolamine. The synthetic substrate p-nitrophenylphosphorylcholine, phosphatidylinositol or sphingomyelin were not hydrolysed. Hydrolysis of phosphatidylcholine was inhibited by EDTA (1mM) and stimulated by Zn2+, Mg2+ ions and detergents. These properties of the enzyme indicate that it is distinct from the previously reported Ps. fluorescens phospholipase C.     

Effect of Ag addition on crystallization in As2Se3 glasses

Differential scanning calorimetry (DSC) behaviours of glassy As₂Se₃ containing Ag up to 5 at % were measured at various heating rates. The effect of addition of Ag on crystallization of glassy As₂Se₃ was investigated. The glass transition temperature decreased with increasing Ag content. Crystallization kinetics were analysed on the basis of the two-step process model, where crystal growth takes place after nucleation. For non-doped As₂Se₃ two-dimensional growth of crystal was predominant, while for Ag-doped ones three-dimensional growth was very likely. It was supposed for all glassy Ag-doped samples that crystal nuclei exist, though micro-crystallites were not observed on X-ray diffraction traces. The activation energy for crystallization and the glass-forming tendency decreased by the addition of Ag.     

The SH2 domain of Shc suppresses EGF-induced mitogenesis in a dominant negative manner

Recently, we have shown that an EGF-R-mutant lacking the autophosphorylation sites phosphorylates Shc and retains mitogenic activity. In this report, we have shown that in these cells, in response to EGF, Ras is fully activated with formation of the tyrosine-phosphorylated Shc-Grb2-mSOS complex without the receptor. This pointed out the importance of Shc in EGF-induced Ras activation. To investigate the mechanism of tyrosine phosphorylation of Shc by EGF-R, we carried out in vitro kinase assays using immunoprecipitated EGF-R and bacterially-expressed Shc proteins as substrates. The EGF-R phosphorylated Shc, but not the Shc SH2 mutant, lacking binding ability for phosphotyrosine. This suggests that intact Shc SH2 is essential for the full-length Shc to become phosphorylated, probably by inducing a conformational change in Shc. Thus a Shc SH2 peptide may inhibit competitively Shc phosphorylation. We microinjected the Shc SH2 domain into NIH3T3 cells overexpressing the EGF-R. Microinjected Shc SH2 greatly suppressed EGF-induced DNA synthesis. But microinjection of neither the Shc SH2 mutant nor PLC-gamma 1 SH2 had any effect. This suppressing effect was rescued by comicroinjection of the full-length Shc, suggesting Shc SH2 specifically suppressed the Shc pathway. Thus we concluded Shc phosphorylation is crucial, whereas receptor autophosphorylation is dispensable, in EGF-induced mitogenesis.