Inhibitory effects of pravastatin, a competitive inhibitor of hydroxymethylglutaryl coenzyme A reductase, on cholesterol gallstone formation in prairie dogs

The effects of pravastatin on cholesterol gallstone formation were determined in prairie dogs. We fed 10 prairie dogs 1% cholesterol with or without 0.05% (w/w) pravastatin (n = 5, each) for 4 weeks. In addition, another 5 prairie dogs were fed a standard rodent chow as a control. Only the animals fed 1% cholesterol without pravastatin treatment formed cholesterol gallstones. Gallbladder bile from cholesterol-fed animals contained cholesterol monohydrate crystals, whereas those treated with pravastatin contained no crystal. Furthermore, marked increases in tissue cholesterol levels (serum, liver and bile), and in biliary mucous glycoprotein levels were evident in cholesterol-fed animals, whereas pravastatin treatment normalized these levels. These findings raise the possibility that such inhibitors might have a future role to play in the prevention of cholesterol gallstone formation and/or recurrence.

Identification and nucleotide sequence of a developmentally regulated gene encoding a eukaryotic histone H1-like protein from Chlamydia trachomatis

A lambda gt11 recombinant library of Chlamydia trachomatis serovar L2 chromosomal DNA was screened with a 29-mer synthetic oligonucleotide specific to the N-terminal amino acids of a predominant 18-kDa chlamydial protein. One recombinant clone, designated lambda gt11/L2/RKA10, was selected on the basis of its strong hybridization signal. Restriction endonuclease analysis and complete nucleotide sequencing of the recombinant revealed a 2,633-bp insert containing one complete open reading frame (ORF2) and two partial ORFs (ORF1 and ORF3). The deduced amino acid sequence of ORF2 matched perfectly at its N-terminal end with the derived amino acid sequence. The 375-bp ORF is capable of encoding a protein comprising 125 amino acids with a molecular mass of 13,689. A sequence compatible with a Shine-Dalgarno ribosome-binding site was located 9 bp upstream from the initiation codon, while the sequence distal to ORF2 revealed a rho-independent terminator. The protein, designated CTH1, possesses an estimated pI of 10.71 due to its high lysine content. This highly basic protein contains no tryptophan or phenylalanine. A protein data base search identified significant homology between CTH1 and painted sea urchin histone H1. Northern (RNA) blot analysis of Chlamydia-infected host cells demonstrated transcripts at 12 h postinfection. The recombinant plasmid encoding ORF2 expressed a gene product of approximately 18 kDa, similar to the native chlamydial protein as analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. This protein appears to represent one of the few eukaryotic histonelike proteins described to date in prokaryotes.

[Isolation of bilirubin oxidase from Myrothecium verrucaria and the optimum conditions of enzyme production]

A bilirubin oxidase (EC 1.3.3.5) producing strain, Mv 2.1089, was isolated from several strains of Myrothecium verrucaria by dilution method. The optimum conditions of enzyme production were investigated and the results were as follows: the suitable medium was cultured at 25 degrees C on a rotating shaker glucose and peptone, at pH 6.0. The strain was cultured at 25 degrees C on a rotating shaker (150 r/min) for 96 h. Bilirubin oxidase with 0.5-1.5 u/ml was obtained in the culture medium.

[A study on the mechanisms whereby apolipoprotein A-1 (apo A-1) inhibits cholesterol crystal nucleation in human gallbladder bile]

The aim of the present study was to determine the mechanisms whereby apo A-1 retards cholesterol crystal nucleation in human gallbladder bile. Ten human gallbladder bile samples were sterilely collected from patients with gallstones at surgery, subsequently applied on gel permeation chromatography to separate various lipid particles. A non-micellar fraction coeluted with apo A-1 was ultrastructurally characterized by transmission electron microscopy (TEM). As results, that fraction containing very little or no apo A-1, 400-600 A in diameter, showed rapid transformation, i.e. rouleau formation, multilamellar formation and consequently microcrystal formation, whereas those rich in apo A-1, 200-400 A in diameter, showed very little transformation for 7 days. Those data indicated that apo A-1 stabilizes non micellar fraction by forming an apo A-1 and lipid complexed particle, resulting in prolonged cholesterol crystal nucleation.

Cyclic AMP inhibits protein synthesis in Chlamydia trachomatis at a transcriptional level

Cyclic AMP (cAMP) has an inhibitory effect on the developmental cycle of Chlamydia trachomatis. We examined its influence on the synthesis of chlamydial protein, using the major outer membrane protein (MOMP) as a marker for general chlamydial protein synthesis. During normal development MOMP synthesis accelerates from 18 h post-infection and peaks by 36 h. Cyclic AMP blocks this normal progression of the chlamydial growth cycle. At a concentration of 1 mM, nearly 75% of the total MOMP synthesis was inhibited by 36 h, as monitored by radiolabel uptake. However, no difference was observed during the first 12 h between cAMP-treated and control groups, a finding which is in keeping with correlation between developmental inhibition and protein synthesis. Hybridization studies carried out with a cloned MOMP gene demonstrate a drastic decrease in MOMP mRNA in cAMP-treated cells. Low levels of cAMP utilized in conjunction with a 100,000 x g supernatant from reticulate bodies (RBs) blocked the transcription of the recombinant MOMP gene in an in vitro transcription system. These results suggest that the inhibition of chlamydial protein synthesis, assessed by MOMP synthesis, is due to regulation at a transcriptional level.

[A clinicopathological study on tumor of the renal pelvis and ureter]

We report 42 patients with urothelial tumors in upper tract admitted to our hospital between August, 1969 and August, 1988. The patients consisted of 33 males and 9 females; their ages ranged from 42 to 85 years with a mean of 66.2 years. Total nephroureterectomy with bladder cuff resection was employed as the surgical method in 24 cases, total nephroureterectomy without bladder cuff resection in 11 cases, total nephroureterectomy with total cystectomy in 2 cases and partial ureterectomy only in 2 cases. Tumor lesions had a positive correlation with grade and stage. The survival rate for all the patients at 1, 3 and 5 years was 76.0, 58.8 and 54.6%, respectively, as measured by the Kaplan-Meier's method. The prognosis of the patients with renal pelvic tumor and ureter tumor was dependent upon grade, stage and intravascular tumor-emboli. Vesical recurrence was observed in 10 cases and found frequently in low grade tumor and/or low stage tumor cases. The frequency of vesical recurrence was not positively correlated with cuff resection The 5-year survival rate was not different between the patients with vesical recurrence and those without vesical recurrence.

[The study on factors affecting cholesterol solubility in bile: relation to biliary proteins including apolipoprotein A-1]

We studied the preferential distribution patterns of cholesterol and proteins to biliary lipid particles isolated from human gallbladder bile by gel permeation chromatography. In addition nucleation times of those bile samples were determined to estimate the metastability of bile cholesterol. Cholesterol dominantly incorporated into a non-micellar fraction in bile from cholesterol gallstone patients with and without preoperative treatment with ursodeoxycholic acid, whereas nucleation time was significantly longer in cholesterol gallstone patients with a preoperative treatment with ursodeoxycholic acid than that of those without any preoperative treatment (p less than 0.01). Furthermore the induced incorporation of apolipoprotein A-1 into a non-micellar fraction was found in bile from cholesterol gallstone patients with ursodeoxycholic acid. These results suggest that stabilizing effects of apolipoprotein A-1 on a non-micellar fraction has been induced by ursodeoxycholic acid treatment resulting in the retardation of cholesterol nucleation in bile.

[Primary carcinoma of the jejunum combined with colon polyp--report of a case]

A 47-year-old female patient with a primary carcinoma of the jejunum combined with colon polyp is presented. Having had an attack of vomiting, she visited our hospital. Oral small intestine radiography revealed a localized stricture with ulceration in the jejunum. Small intestinal endoscopy showed a tumor with an irregular surface and hemorrhagic ulceration. Selective superior mesenteric arteriography revealed a stenosis and deviation of arteries. These findings strongly indicated cancer of the jejunum, and a barium enema study and a colonoscopic examination revealed a polyp in the ascending colon. The resected tumor was histologically diagnosed as a well differentiated adenocarcinoma. CEA-positive cells also were observed. Further, a polypoid lesion in the colon was histologically diagnosed as an adenoma.

Comparative study of hepatocellular carcinoma in Shikoku, Japan: a study of 198 autopsy cases in Tokushima and Ehime Prefectures

A total of 198 cases with hepatocellular carcinoma (HCC) autopsied in two different areas in Shikoku, Tokushima and Ehime, was examined clinicopathologically. The incidence of HBsAg-positives in overall HCC cases was 49.0%, being higher in Tokushima (52.4%) than in Ehime (43.1%). The difference seemed to be caused by the high incidence in female cases in Tokushima (46.7% in Tokushima vs. 23.1% in Ehime). The mean age of HCC cases with HBsAg (53.9 years) is younger than that of cases without HBsAg (58.8 years). The incidence of HBsAg-positive HCC cases in Shikoku decreased step by step toward older age groups from 63.4% in 41-50, 59.5% in 51-60, 34.6% in 61-70, to 15.8% in over-71 age groups, and has been decreasing gradually with the passage of time from 57.1% in 1960-1971, 50.0% in 1972-1976, to 40.8% in 1977-1981. The incidences of HBsAg-negatives in all autopsy cases increased from 2.0% in 1960-1971 to 3.3% in 1977-1981 (P less than 0.05) although the incidences of HBsAg-positives showed almost the same level. Both in Tokushima and Ehime, the incidences of HCC associated with cirrhosis and HCC with HBsAg were smaller in grade IV cases, and the incidence of HBsAg-positive HCC was high in cases with macronodular type of cirrhosis.

Measurement of effects of the Chinese herbal medicine higenamine on left ventricular function using a cardiac probe

The effects of the Chinese herbal medicine higenamine on left ventricular function were studied by means of an external radiation detector in 15 patients with heart disease. Higenamine, administered intravenously, markedly increased the ejection fraction of LV, as well as the ejection rate. The LVEF increased from 46% +/- 9% to 60% +/- 15% and 61% +/- 12% (P less than 0.005) after a 30- and 60-min infusion of higenamine, respectively. The percentage increase in LVEF paralleled the increase in the heart rate. The effects of higenamine on LV function were similar to the response obtained with isoproterenol. These results document the pharmacologic effect of the Chinese herbal medicine, higenamine, on heart function.

Evidence for a lack of an effect of dietary fluoride level on reproduction in mice

The possible essentiality of fluoride for reproduction was studied in female mice fed a low-fluoride ( less than 0.5 ppm F) basal diet for three generations. Reproduction of mice fed this basal diet was the same as when mice were fed the basal diet supplemented with 2 or 100 ppm F. A previous study [Messer et. al. (1973) J. Nutr. 103, 1319-1326], utilizing the same diet did result in an impairment of reproduction and the development of an anemic condition. The results of the present study suggest that the apparent essentiality of fluoride previously observed was due to a pharmacological effect of fluoride in improving iron utilization in a diet marginally sufficient in iron. The data do not support the previous claims of an essential role of fluoride in reproduction.