Resin corrosion cast (Mercox) in experimental evaluation of small vessel anastomosis

This study focuses on obtaining more information about the site of anastomosis, with three-dimensional examination using methylmethacrylate resin (Mercox) corrosion casts. Seventy microvascular anastomoses were performed in Wistar albino rats, divided into two groups before sacrifice. In Group 1 (35), Mercox was injected into the vessels, whereas in Group 2 (35), the tissues were prepared without injecting Mercox. Both groups were compared under the scanning electron microscope (SEM). The SEM preparation in Group 1 was simple, easy, and artifacts were significantly minimized. The anastomotic site could be well appreciated in three-dimensional views. Clear negative imprints of the endothelial surface were achieved without any breakage in the Mercox corrosion cast, and it can be reliably used in the evaluation of small vessel anastomosis.     

Immunological study on chyluria

Immunological studies were performed in 87 patients with chyluria referred to our clinic from January 1982 to December 1988. White blood cell count in 78 patients was 5210.3 +/- 1440.9/mm3. The fraction and the number of lymphocyte were 18.7 +/- 9.5% and 934.1 +/- 521.6/mm3, respectively: they were lower than normal limit. The percentages of T and B lymphocytes studied in 46 patients were 79.3% +/- 11.2% (normal range: 76-86) and 10.4 +/- 7.9% (normal range: 8-16), respectively: both lymphocytes tended to decrease in percentage. Lymphocyte blast formation stimulated with phytohemagglutinin (PHA) was carried out in 20 patients. The mean of the blast formation was 17410.0 +/- 10275.1 c.p.m. (normal range: 377700-62400), and much lower than normal value. Of 22 patients who had PPD skin test, only 9 (40.9%) were positive. These findings signified that cellular immunity was suppressed in patients with chyluria. On the other hand, the value of immunoglobulin was within normal range (IgG: 1325.3 +/- 475.6 mg/dl, IgA: 242.0 +/- 98.3 mg/dl, IgM 130.4 +/- 95.9 mg/dl). Study on the values of laboratory examinations showed statistically positive correlation between total lymphocyte population and T cell number, and between total lymphocyte population and lymphocyte blast formation. In patients with chyluria, serious sequelae have not been reported. However, care should be taken for possible opportunistic infection and, particularly, malignant tumors because suppression of cellular immunity may be one of the promoting factors of malignant tumors.     

Protective effect of prostaglandins D2, E1 and I2 against cerebral hypoxia/anoxia in mice

The protective effect of prostaglandins (PGs) against cerebral hypoxia/anoxia was investigated with a variety of experimental models in relation to their CNS depressant effects in mice. Furthermore, the effect of PGs on the changes of cerebral energy metabolites and cyclic nucleotide was examined in hypoxic mice. Mice were given s.c. doses of PGs 30 min before tests. Among the PGs tested, treatment with PGD2, PGE1 and PGI2 Na showed a consistent and dose-dependent protection against cerebral anoxia induced by all models studied: histotoxic anoxia by KCN, hypobaric hypoxia, normobaric hypoxia and decapitation-induced gasping. However, PGA1, PGA2, PGB1, PGB2, PGE2, PGF1 alpha, PGF2 alpha and 6-keto-PGF1 alpha at a dose of 3 mg/kg were without effect against normobaric hypoxia and gasping duration. The three PGs, i.e. PGD2, PGE1 and PGI2 which showed anti-hypoxic effects decreased locomotor activity and potentiated hexobarbital-induced sleep. On the other hand, PGE2, PGA1, PGA2 and PGB2 also caused a decrease in locomotor activity. Similarly, PGE2 and PGA1 caused a potentiation of hexobarbital-induced sleep, but interestingly they did not cause clear-cut increase in cerebral resistance to hypoxia, in contrast with the former three PGs. Thus general depression of CNS function appears not to be responsible for the PGD2-, PGE1- and PGI2-induced increase in cerebral resistance to hypoxia. The levels of Cr-P and ATP were significantly reduced and those of ADP and AMP were markedly elevated in hypoxic brain, resulting in a decrease in a calculated energy charge potential. The lactate level and lactate/pyruvate ratio increased and the glucose level decreased markedly.(ABSTRACT TRUNCATED AT 250 WORDS)     

Characteristics of young-onset hypertension identified by targeted screening performed at a university health check-up.

Since the prevalence and clinical characteristics of young-onset hypertension are still to be elucidated, we performed targeted-screening at an annual university health check-up for two consecutive years. Out of 16,464 subjects in 2003 and 17,032 in 2004 that were aged less than 30 years, 22 and 26 students (all males) exhibited high blood pressure (BP), respectively, on three occasions during casual BP measurements at the Tohoku University Health Center (systolic and diastolic BP of 140 and/or 90 mmHg or greater, respectively). These students were asked to measure their BP at home, and 9 subjects in total were diagnosed as having essential hypertension (EH). The remaining students were diagnosed as having white coat hypertension (WCH). In 8 out of 9 EH students, their father and/or mother had also been treated with antihypertensive medication. Adjustment by attendance ratio for each BP measurement suggested that the incidence of EH was around 0.1% and that of hypertension (EH and WCH) was around 0.5% in university students aged less than 25 years, since most of the subjects and hypertensive students were between 18 and 24 years old. Body mass index of the EH, which was more than 25 kg/m2 (overweight), was significantly higher than that with WCH. In conclusion, the combination of repeated casual BP measurements and home BP effectively identified young-onset EH. The clinical parameters indicated that male gender, genetic background, and excessive weight were risk factors for young-onset hypertension.     

Stimulation of monocyte iodination and IL-1 production by tannins and related compounds.

Various tannins and related compounds were compared for their ability to stimulate the iodination (incorporation of radioactive iodine into an acid-insoluble fraction) of human peripheral blood monocytes. The stimulating activity of most of the monomeric and dimeric hydrolyzable tannins was generally higher than that of the trimeric and tetrameric compounds. Compounds that had dehydrohexahydroxydiphenoyl or chebuloyl groups had considerably less activity than those that had other functional groups (hexahydroxydiphenoyl, valoneoyl, dehydrodigalloyl, isodehydrodigalloyl, lactonized valoneoyl, hellinoyl, euphorbinoyl, dehydroeuphorbinoyl or woodfordinoyl group). The methylated derivative, nonacosa-O-methylcoriariin A, was essentially inactive, suggesting the requirement of a phenolic hydroxyl group. Three condensed tannins ((-)-epicatechin 3-O-gallate (ECG)-dimer, ECG-trimer and ECG-tetramer) significantly stimulated both monocyte iodination and their interleukin-1-like factor production. The results suggest the dependence of stimulation of monocyte iodination by tannins and related polyphenols on molecular weight.     

Strain Difference of Susceptibility to 4-Nitroquinoline 1-Oxide-induced Tongue Carcinoma in Rats

Strain difference of susceptibility to 4-nitroquinoline 1-oxide (4NQO)-induced squamous cell carcinomas of the tongue among Dark-Agouti, Long-Evans, Sprague-Dawley, ACI/Ms, Fischer 344, Donryu and Wistar/Furth rats was surveyed by evaluating the survival times, incidences and sizes of developed tumors as markers of susceptibility. Administration of 4NQO dissolved in drinking water induced squamous cell carcinomas in various sites of the upper digestive tract mucosa of all the experimental male and female rats of the seven strains. Regarding the mean survival times, Wistar/Furth rats survived much longer than any other strain of rats, and Dark-Agouti showed the shortest survival. The incidence of large, mass-type carcinomas of the tongue of Dark-Agouti rats was higher than in any other strain of rats, while that of Wistar/Furth rats was the lowest. Subsequently the mitotic activity and bromodeoxyuridine incorporation in the tongue epithelium of Dark-Agouti and Wistar/Furth rats were estimated after a short-term administration of 4NQO. There was a pronounced difference between the two strains of rats, because the proliferative responses of the tongue epithelium of Dark-Agouti rats to the 4NQO stimulation were much higher than those of Wistar/Furth rats. These results indicated that there are marked differences in the susceptibility to 4NQO-induced tongue carcinoma among the seven strains of rats, and that Dark-Agouti and Wistar/Furth rats could be useful as models of highly and poorly susceptible strains, respectively, for further genetic analysis.