Normal thermostability of hypoxanthine guanine phosphoribosyltransferase in erythrocytes from Werner's syndrome patients

The thermostability of erythrocyte hypoxanthine guanine phosphoribosyltransferase of 2 Werner's syndrome patients was compared with that of normal subjects of different ages. No significant difference was observed regarding the thermal stability of the enzyme among normal subjects and Werner's syndrome patients. The activities of other erythrocyte enzymes, phosphoribosylpyrophosphate synthetase, adenine phosphoribosyltransferase, adenosine deaminase and purine nucleoside phosphorylase, were similar between Werner's syndrome and normal subjects.     

Cytoarchitecture and fiber connections of the superficial pretectum in a teleost,Navodon modestus

Fiber connections of the so-called nucleus geniculatus lateralis (or the nucleus pretectalis superficialis pars parvocellularis) in a teleost, Navodon modestus, were examined by means of the horseradish peroxidase (HRP) tracing method. The nucleus receives fibers from the contralateral retina, ipsilateral optic tectum and nucleus isthmi, and projects bilaterally to the nucleus intermedius of Brickner and ipsilaterally to the optic tectum and raphe nuclei. The fiber connections suggest that the nucleus relays mainly visual information to the inferior lobe (hypothalamus) but not to the telencephalon. The nucleus is not a homologous structure to the lateral geniculate nucleus in other vertebrate classes.     

Expression of human placenta alkaline phosphatase in placenta during pregnancy

To clarify the expression of PLAP during the course of pregnancy, the amount of PLAP mRNA and its activity in normal placental villi were measured. Both PLAP and its mRNA were found in placentae of as early as 7 weeks of gestation, and they continued to increase throughout pregnancy. But they showed different patterns of increase. The amount of PLAP mRNA began to increase dramatically around 13th week and probably continued to increase gradually until term. PLAP activity per gram of villi showed a gradual increase from around 13th week and a marked increase was observed after about 20th week. PLAP levels in sera from pregnant women were also measured, and they showed a pattern of increase imilar to that of PLAP activity per gram of villi. The continuous increase in the expression of PLAP throughout pregnancy suggests that PLAP may play a role in feto-maternal metabolism and placental differentiation.     

Effect of pancreastatin on cerulein-stimulated pancreatic blood flow and exocrine secretion in anaesthetized rats

BACKGROUND: Pancreastatin (PST) is an inhibitor of pancreatic exocrine secretion in vivo but not in vitro, which suggests that the inhibitory effect of PST is indirect, that is, not mediated by a specific receptor on pancreatic acinar cells. In this study, we investigated the effects of PST on pancreatic exocrine secretion and local pancreatic blood flow in anaesthetized rats to elucidate the participation of PST in indirect regulation of pancreatic exocrine function through blood supply. METHODS: Pancreastatin (100, 200 or 500 pmol/kg per h) was administered intravenously under background infusion of cerulein (0.5 microg/kg per h), a cholecystokinin analogue. Pancreatic exocrine secretion was monitored by volume and protein output of the pancreatic juice and local pancreatic blood flow was measured by the hydrogen gas clearance method. RESULTS: Pancreastatin significantly reduced cerulein-induced local pancreatic blood flow in a dose-dependent manner. Pancreatic exocrine secretion was also reduced significantly by PST dose-dependently. Pancreastatin did not change systemic blood pressure.These results suggested that the reduction of pancreatic blood flow is associated with the reduction of pancreatic exocrine secretion. CONCLUSIONS: We conclude that the mechanism of PST-induced inhibition of pancreatic exocrine secretion is, at least, partly mediated by the reduction of local pancreatic blood flow through blockade, caused by the action of cerulein on pancreatic blood flow.     

Incremental value of assessment of regional wall motion for detection of multivessel coronary artery disease in exercise (201)Tl gated myocardial perfusion imaging.

Assessment of reversible perfusion defects in exercise (201)Tl perfusion SPECT has low sensitivity and high specificity for detection of multivessel coronary artery disease (CAD). The goal of this study was to evaluate whether worsening of left ventricular regional wall motion assessed by an automated algorithm in exercise (201)Tl electrocardiography-gated SPECT had incremental diagnostic value over perfusion data for detection of multivessel CAD. METHODS: Two hundred one patients underwent exercise (201)Tl gated SPECT. Software that automatically analyzes left ventricular function was used to assess exercise and rest regional wall motion. Regional wall motion on initial images was compared with that on rest images, that is, delayed images for patients without reinjection images and reinjection images for patients with reinjection images. The left ventricle was divided into 9 segments, with individual segments assigned to 3 coronary territories. Worsening of wall motion was defined as worsening in any segment on initial images compared with rest images. RESULTS: Of 73 patients with multivessel CAD, 20 (27.4%) had reversible perfusion defects in multiple coronary territories, 26 (35.6%) exhibited worsening of regional wall motion in multiple territories, and 37 (50.7%) had reversible perfusion defects or worsening of regional wall motion in multiple territories. The sensitivity of the combination of reversible perfusion defect and worsening of regional wall motion was significantly higher than that of reversible perfusion defect alone for detection of multivessel CAD (50.7% vs. 27.4%, P < 0.05). The specificity of the combination of reversible perfusion defect and worsening of regional wall motion for detecting multivessel CAD did not differ from that of reversible perfusion defect alone and that of worsening of regional wall motion alone (94.5% vs. 99.2% and 97.7%, respectively, P = not statistically significant). CONCLUSION: Combined assessment of worsening of left ventricular regional wall motion by exercise and perfusion data in exercise (201)Tl gated myocardial SPECT was more sensitive, with acceptable specificity, than was assessment with perfusion data alone for detection of multivessel CAD.     

Treatment of persistent corneal epithelial defect by autologous serum application.

OBJECTIVE: To evaluate the efficacy of autologous serum application for the treatment of persistent epithelial defect. DESIGN: Prospective, clinical, noncomparative case series. PARTICIPANTS: A total of 16 eyes were studied. INTERVENTION: Autologous serum was prepared from the patients and diluted to 20% by saline. The patients were instructed to use the autologous serum six to ten times a day. The concentration of vitamin A, epidermal growth factor (EGF), and transforming growth factor-beta (TGF-beta) was measured at 1 week and 1 month stored in the refrigerator and 1 month and 3 months in the freezer. MAIN OUTCOME MEASURES: Time to closure of epithelial defect. RESULTS: Vitamin A, EGF, and TGF-beta were stable during the 1 month in the refrigerator and 3 months in the freezer. Among 16 persistent epithelial defects, 7 (43.8%) healed within 2 weeks, 3 (18.8%) healed within 1 month, and the remaining 6 (37.5%) did not respond within 1 month. No apparent side effect of autologous serum application was observed. CONCLUSIONS: Autologous serum application healed 43.8% of persistent defect within 2 weeks and 62.5% within 1 month.     

Image analysis of CNS neurotrophic factor effects on neuronal survival and neurite outgrowth

We have developed a method for quantifying the effects of neurotrophic factors by using digital image processing techniques to enhance the morphometric analysis of cultured neurons. Dissociated cell cultures from rat embryonic cerebral cortex were selected as a model biological system. Binary images of neuronal neurites were extracted from gray images of cultured neurons stained with Coomassie brilliant blue. Pattern recognition techniques were used to estimate the number of neurons per culture dish and the average length of the neurites on each cell. In 4-day cultures, addition of extracts from 2-week-old rat cortices dose-dependently increased both parameters. The method proved suitable for use in bioassays of factors influencing neuronal survival and neurite promotion.     

Intrahepatic recurrences of hepatocellular carcinoma after hepatectomy: analysis based on tumor hemodynamics.

HYPOTHESIS: Surgical margin, i.e., the area of possible local intrahepatic metastasis, is controversial in hepatectomy for hepatocellular carcinoma. DESIGN: The blood drainage area of tumor was identified preoperatively by abdominal helical computed tomographic scan under hepatic arteriography and excised as surgical margin. The specimens were pathologically examined on the basis of the corresponding computed tomographic images. SETTING: University hospital. PATIENTS: From June 2, 1997, to April 24, 2000, 67 patients with hepatocellular carcinoma who underwent curative hepatic resection. MAIN OUTCOME MEASURE: Intrahepatic recurrence. RESULTS: Blood drainage area of tumor could be classified into the following types. The marginal type (drainage into the peritumorous area) was frequent (50 cases) and excised mostly by nonanatomic, limited resection. Portal vein type (drainage into the portal branches) was less common (12 cases) and resected mostly by anatomically systematic hepatectomy. The remaining 5 cases were of the hypovascular type and underwent limited resection. Multiple nodules were frequently found inside the drainage area (4 of 8 cases) and were moderate or poorly differentiated hepatocellular carcinoma, consistent with intrahepatic metastasis. Solitary nodules were mostly outside the drainage area (11 of 12 cases) and contained well-differentiated hepatocellular carcinoma (7 of 10 cases), suggesting multicentric carcinogenesis. Intrahepatic recurrences were commonly found in bilateral or contralateral lobes (17 of 19 cases) and divided into 2 groups with a few (< or =4) and multiple (> or =8) recurrent nodules. CONCLUSIONS: Surgical margin varied according to tumor hemodynamics. Tumor recurrences may result not only from multicentric carcinogenesis but also from intrahepatic metastasis via systemic circulation.