Repeated piezoelectric lithotripsy for gallstones with and without ursodeoxycholic acid dissolution: a multicenter study.

The use of bile acid dissolution therapy in extracorporeal shockwave lithotripsy of gallstones, remains controversial. Our study examined whether chemolitholysis after sufficient disintegration enhanced stone clearance within 6 months of the first lithotripsy. A total of 143 patients who developed one to three radiolucent stones measuring < or = 30 mm in diameter were randomly separated into two treatment groups: 47% were given lithotripsy alone, and 53% lithotripsy plus ursodeoxycholic acid (UDCA). Repeated piezoelectric lithotripsy was given, with no limit on the total number of treatment sessions, to pulverize or disintegrate stones into fragments < 3 mm. Stones were disintegrated in 97% of all patients, and the fragments were < or = 2 mm in 50% of these patients. According to an intention-to-treat analysis, 52% in the lithotripsy alone group and 58% in the UDCA group were free of stones 6 months after the first lithotripsy (P = 0.61). Of the patients with fragments < or = 2 mm, 71% in the former and 86% in the latter group were free of stones 6 months after the first lithotripsy, with no significant difference between the groups. Biliary pain occurred in 25% of all patients, including 3 with acute cholecystitis. We concluded that the sufficient disintegration of gallstones achieved with repeated lithotripsy enhanced the early clearance of fragments, regardless of whether chemolitholysis was employed.

Prophylaxis of genetically determined diabetes by diazoxide: a study in a rat model of naturally occurring obese diabetes.

The study was carried out using a new rat model of naturally occurring obese, nonketotic diabetes, Otsuka Long-Evans Tokushima Fatty rat (Kawano et al., Diabetes 41: 1422-1428, 1992), which closely resembles obese noninsulin-dependent diabetes in human. At the age of 3.5 wk, body weight, glucose tolerance and plasma insulin level after glucose load were normal in Otsuka Long-Evans Tokushima Fatty rats, indicating the animals are at nonobese, prediabetic phase. At this age, however, glucose-stimulated insulin release by pancreatic islets in vitro was abnormally exaggerated whereas the islet insulin content and glucose metabolism by the islet cells were normal. Administration of diazoxide (0.2% in diet), an inhibitor of insulin secretion, to Otsuka Long-Evans Tokushima Fatty rats from the age of 4 to 12 wk completely prevented the development of obesity and insulin resistance, which was accompanied by marked improvement of glucose tolerance and disappearance of exaggerated B cell response to glucose in vitro. This is the first report of successful pharmacological prevention of genetically determined obese diabetes.

Mechanism of glucose-induced biphasic insulin release: physiological role of adenosine triphosphate-sensitive K+ channel-independent glucose action.

The mechanism of glucose-induced biphasic insulin release by the B cell was investigated using isolated rat pancreatic islets. In perifusion experiments, 16.7 mM glucose in combination with 25 mM K+ transformed the high K(+)-induced monophasic insulin release into a biphasic one in the presence of diazoxide (Dz), an ATP-sensitive K+ channel opener. Inclusion of Dz during the initial 6 min of glucose stimulation abolished the first phase, but was without effect on the second phase. In batch incubation experiments, fuels, including 16.7 mM glucose, 6 mM D-glyceraldehyde, and 10 mM 2-ketoisocaproate, but not sulfonylurea, caused time-dependent potentiation of the B cell so that the response to 25 mM K+, applied later, was increased in the fuel-primed islets. Inclusion of Dz or lowering extracellular Ca2+ (to micromolar range) during the priming, which eliminates the initiation of insulin release, did not eradicate the potentiation. We conclude that high glucose closes ATP-sensitive K+ channels, leading to membrane depolarization, Ca2+ influx, and initiation of insulin release (first phase), and subsequently self-augments insulin release in an ATP-sensitive K+ channel-independent manner (second phase), acting at steps distal to cytosolic Ca2+ elevation. The biphasic insulin release is thus generated by an interaction of ATP-sensitive K+ channel-dependent and -independent glucose actions.

Effect of parathyroid hormone on left ventricular diastolic function in patients with primary hyperparathyroidism.

To evaluate the effect of parathyroid hormone (PTH) on diastolic function, left ventricular (LV) diastolic filling dynamics were studied using pulsed Doppler echocardiography in patients with untreated primary hyperparathyroidism (HPT; mean age 59 years) and control subjects. In patients with primary HPT, the ratio of peak flow velocity of atrial filling wave to peak flow velocity of early filling wave (A/E) was studied immediately before and 1 month after parathyroidectomy (PTX). A/E is significantly higher in the patients with primary HPT than in the control subjects. A/E decreased significantly after PTX. A/E was strongly correlated with PTH levels, but not with calcium levels in patients with primary HPT. It is concluded that LV diastolic function is abnormal in patients with primary HPT, which could result from elevated PTH rather than hypercalcemia.

Effects of thapsigargin, an intracellular CA2+ pump inhibitor, on insulin release by rat pancreatic B-cell.

This is the first report as to the effects of thapsigargin (Tg), an inhibitor of intracellular Ca2+ pumps, on insulin release by pancreatic B-cells. Tg does not alter basal insulin release by the isolated islets, with 3 mM glucose. However, it potentiates high glucose-induced insulin release: potentiation of the first phase response is dose-related in a concentration range of 1.3-40 microM. In isolated B-cells, Tg causes a minimal rise in basal cytosolic free calcium concentration ([Ca2+]i) and eliminates high glucose-induced initial lowering of [Ca2+]i. Tg does not alter glucose oxidation by the islets and the islet insulin content. An elimination of glucose-induced sequestration of Ca2+ into Tg-sensitive intracellular pool(s) is considered to be the cause of Tg potentiation of glucose effect on insulin release.

Differential metabolic requirement for initiation and augmentation of insulin release by glucose: a study with rat pancreatic islets.

Insulin release, glucose utilization (3H2O formation from [5-3H]glucose), and glucose oxidation (14CO2 formation from [14C(U)]glucose) were determined in pancreatic islets from 96-h fasted rats at 37 degrees C and those from fed rats at 22 degrees C, using the islets from fed rats incubated at 37 degrees C as controls. In the islets from 96-h fasted rats and those from fed rats incubated at 22 degrees C, we could not demonstrate significant insulin release in response to high glucose concentrations of up to 16.7 mmol/l. However, 16.7 mmol/l glucose clearly augmented insulin release caused by a depolarizing concentration (50 mmol/l) of K+ in these islets: i.e. 16.7 mmol/l glucose plus 50 mmol/l K+ produced significantly greater insulin release than 50 mmol/l K+ alone. Glucose utilization and oxidation by the islet cells were suppressed by 96-h fasting of the rats or by lowering the incubation temperature to 22 degrees C, and depolarization with K+ at 50 mmol/l did not at all augment glucose utilization and oxidation by the islets. Thus we conclude that reduction of glucose metabolism in islets from fasted rats and in those incubated at low temperature eliminated initiation, but not augmentation, of insulin release by 16.7 mmol/l glucose. The data indicate that the metabolic threshold for the initiation of insulin release is significantly higher than it is for the augmentation of release by glucose.

Insulin secretion by the pancreatic beta cell of aged rats.

Insulin release by the pancreatic islets of 12-week- and 2-year-old male Wistar rats was compared using glucose and non-fuel secretagogues such as forskolin, phorbol ester (12-O-tetradecanoylphorbol-13-acetate) and glyburide acting on adenylyl cyclase, C kinase, and the ATP-sensitive K+ channel, respectively. Sensitivity of the voltage-dependent calcium channel to nifedipine was also examined. In the beta cell of aged rats, the following abnormalities were found: (a) right shift of the dose-response curve (depressed sensitivity) of glucose-induced insulin release, (b) no increase of the maximum response to glucose in the face of increased insulin content of the islets (reduced responsiveness), (c) no response to forskolin and normal response to the phorbol ester and glyburide, and (d) increased sensitivity to nifedipine. In the beta cell of aged rats, sensitivity and responsiveness to glucose are depressed and cyclic AMP-dependent exocytosis and the calcium channel are abnormal.

ATP-sensitive K+ channel-independent glucose action in rat pancreatic beta-cell.

The nature of ATP-sensitive K+ (K+ATP) channel-independent, insulinotropic action of glucose was investigated using non-glucose-primed pancreatic islets. When the beta-cell was depolarized with K+, glucose dose dependently stimulated insulin release despite inhibition of the K+ATP channel closure by diazoxide. K+ depolarization could be replaced with BAY K 8644, a calcium channel agonist. Prior fasting of rats and lowering ambient temperature greatly suppressed glucose oxidation and utilization by the islet cells and abolished insulin release in response to high glucose alone. However, under these conditions, the K+ATP channel-independent, glucose-induced insulin release was clearly demonstrable. p-Nitrophenyl-alpha-D-glucopyranoside (sweet taste inhibitor) but not its beta-isomer, neomycin (phospholipase C inhibitor) and staurosporine (C kinase blocker) inhibited the K+ATP channel-independent, insulinotropic action of glucose. For the K+ATP channel-independent glucose-induced insulin release 1) elevation of cytosolic calcium is required, 2) minute glucose metabolism is enough, if glucose metabolism is necessary, and 3) direct recognition of glucose molecule, phospholipase C, and protein kinase C appear to be involved.

Possible link between a low prevalence of cardiovascular disease and mild dyslipidaemia: a study in Japanese patients with type 2 diabetes.

In 98 Japanese patients with Type 2 diabetes mellitus, serum total cholesterol, triglyceride, high density lipoprotein cholesterol (HDL-C), free fatty acid (FFA), and apolipoproteins (apo) A-I, A-II, B, C-II, C-III, and E were determined. The data were compared with those in 47 normolipidaemic normal controls. The total cholesterol value of the diabetic patients was also compared to that of a general population (n = 2227). The diabetic patients were separated into those with cardiovascular disease (n = 20) and without it (n = 78) and a comparison of clinical characteristics and dyslipidaemia was also performed. The diabetic patients had slightly but significantly higher FFA, LDL-C, apo B, C-II, C-III, E, and B/A-I, and lower apo A-I and A-II compared to the normal controls. The total cholesterol level of the diabetic patients (5.17 +/- 0.96 mmol-1) was not significantly higher than that of the general population (5.12 +/- 0.91 mmol-1). By multivariate stepwise discriminant analyses, only total cholesterol significantly discriminated the patients with and without cardiovascular disease. In Japanese patients with Type 2 diabetes, a diabetic population with a very low prevalence of cardiovascular disease, high total cholesterol is a risk factor for developing cardiovascular disease. Nevertheless, a markedly low prevalence of cardiovascular disease in Japanese with Type 2 diabetes compared to Caucasian counterparts may partly be due to the mildness of dyslipidaemia.

Role of dehydroepiandrosterone and dehydroepiandrosterone sulfate for the maintenance of axillary hair in women.

To delineate the relationship between sex hormones and the axillary hair in women, serum concentrations of dehydroepiandrosterone, dehydroepiandrosterone sulfate and testosterone were measured in 177 normal women (aged 16 to 76 y). Both menstrual cycle and axillary hair were present in all normal women younger than 50 years. In the 6th decade, axillary hair was present in 21 of 42 normal women but menstruation was present only in 8 of the 42 women. In the 7th and 8th decades, axillary hair was present in 36% and 25% of them, respectively. None of the subjects over 60 years of age had a menstrual cycle. Serum dehydroepiandrosterone and dehydroepiandrosterone-sulfate concentrations were significantly higher in axillary hair-positive than in -negative women after 50 years of age. Serum testosterone concentration was low in normal women after 50 years of age compared to those of under 49 years, and it was marginally lower in axillary hair-negative than in -positive normal women. However the difference between the axillary hair-positive and -negative subjects was not statistically significant. It is suggested that weak adrenal androgens such as dehydroepiandrosterone and dehydroepiandrosterone-sulfate, rather than testosterone, play an important role for the maintenance of axillary hair in aged women.

Left ventricular filling abnormalities in non-insulin-dependent diabetes mellitus and improvement by a short-term glycemic control.

To determine whether left ventricular (LV) filling abnormalities in diabetes are associated with diabetic microangiopathy, and to evaluate the effect of a short-term glycemic control on the filling abnormalities, diastolic filling dynamics were assessed by pulsed Doppler echocardiography in 246 patients with non-insulin-dependent diabetics. Isovolumic relaxation time and the ratio of peak flow velocity of atrial filling wave to peak flow velocity of early filling wave (A/E) were significantly greater in diabetic patients than in age- and sex-matched control subjects. Diabetic patients with retinopathy had significantly greater isovolumic relaxation time and A/E values than those without retinopathy. A/E was significantly decreased 1 month after insulin treatment in those without, but not with retinopathy. It is concluded that LV diastolic filling is impaired in mildly hyperglycemic patients with non-insulin-dependent diabetes mellitus without severe complications, the abnormality being more intense in patients with retinopathy. A short-term glycemic control results in a marked decrease in abnormalities in patients without, but not with retinopathy.

Role of adrenal androgens in the development of arteriosclerosis as judged by pulse wave velocity and calcification of the aorta.

To evaluate the role of adrenal androgens in the development of arteriosclerosis, serum dehydroepiandrosterone sulfate (DHEAS), dehydroepiandrosterone (DHEA), aortic calcification and pulse wave velocity (PWV) were measured in 69 males and 119 females without overt cardiovascular disease. The steroids decreased with age in both sexes, and the reduction was significantly steeper in younger (< or = 40 years) than in older (> 40 years) subjects only in females. When adjusted for age, the steroids were significantly lower in subjects with aortic calcification than in those without it, and the PWV was significantly slower in the latter. Adrenal androgens appear to retard the development and/or progression of arteriosclerosis.

Silent myocardial ischemia in patients with non-insulin-dependent diabetes mellitus as judged by treadmill exercise testing and coronary angiography.

Patients with diabetes were compared with nondiabetic control subjects, with respect to the prevalence of silent myocardial ischemia, by means of treadmill exercise testing and coronary angiography. Results of treadmill exercise testing showed ischemic ST depression in 41 of the 132 diabetic patients (mean age 61 +/- 4 years) and in 42 of the 140 nondiabetic control subjects (mean age 60 +/- 8 years) (31% vs 30%, p = NS). Coronary angiography was performed in 36 of 41 diabetic patients and 34 of 42 nondiabetic control subjects with positive results of treadmill exercise tests, who gave their consent. Among "treadmill-positive" subjects, diabetic patients had a prevalence of silent myocardial ischemia that was 2.2 times higher than that in nondiabetic control subjects (p less than 0.05). Diabetic patients who received insulin had a 2.6 times higher prevalence of silent myocardial ischemia than those who did not (p less than 0.05). Similarly diabetic patients with retinopathy has a 2.5 times higher prevalence of silent myocardial ischemia than those without it (p less than 0.05).

Cloning and expression of endo-beta-1,3-glucanase gene from Flavobacterium dormitator in Escherichia coli and characterization of the gene product.

The beta-1,3-glucanase (1,3-beta-D-glucan glucanohydrolase, EC 3.2.1.6) gene from Flavobacterium dormitator var. glucanolyticae was cloned into Escherichia coli C600 with a vector plasmid, pBR322. The E. coli cells carrying a recombinant plasmid, pKU beta G1 (8.2 kb), showed a high beta-1,3-glucanase activity and a lytic activity on viable yeast cells. These activities were found in the periplasmic space of E. coli clone cells. Southern hybridization analysis showed that the cloned gene was derived from F. dormitator chromosomal DNA. The gene products were purified from the periplasmic fraction of E. coli by ammonium sulfate fractionation and ion-exchange chromatography. The purified enzymes were demonstrated to be identical with a lytic endo-beta-1,3-glucanase II and a nonlytic endo-beta-1,3-glucanase I from F. dormitator from their enzymological and immunological properties. In the E. coli cells, endo-beta-1,3-glucanase I was also formed by a proteolytic digestion of endo-beta-1,3-glucanase II during the cultivation as in F. dormitator. Thus, the only endo-beta-1,3-glucanase II was coded for in the cloned gene.

[A case of B-cell non-Hodgkin's lymphoma with prominent splenomegaly and high serum titer of cold agglutinin].

The case of 37-year-old male with non-Hodgkin's lymphoma with prominent splenomegaly is presented. The spleen that was removed for analysis had a weight of 2690 grams and a section inspection revealed multiple, whitish, small nodules that were disseminated throughout the entire spleen. It was microscopically demonstrated to be a B-Cell lymphoma of diffuse, medium-sized cells and an IgM.kappa Type. This case also was complicated by a high serum titer of cold agglutinin that was decreased by chemotherapy.

Role of cell wall in Saccharomyces cerevisiae mutants resistant to Hg2+.

Hg2+-resistant mutants were isolated from Saccharomyces cerevisiae. Although they were very much like the parental strains in terms of colony-forming ability, they grew faster than the parental strains in the presence of sublethal doses of Hg2+. The Hg2+-resistant mutations were dominant. They were centromere linked and were divided into two groups by means of recombination; one of the mutations, designated HGR1-1, was mapped on chromosome IV because of its linkage to the TRP1 locus. The Hg2+-resistant mutants took up Hg2+ as much as, or slightly more than, the parental strains did. The mutants and parental strains retained only about 5 and 15%, respectively, of the cell-associated Hg2+ after removal of the cell wall; therefore, the mutants had less spheroplast-associated Hg2+ than did the parental strains. These results indicate that the cell wall plays an important role in protection against Hg2+ by acting as an adsorption filter and that the mutations described confer Hg2+ resistance by increasing the Hg2+-binding capacity of the cell wall.