Does the stomach remain silent after neonatal loss of its original pacemaker?: gastric motility in long-term survivors of neonatal gastric rupture

Gastric peristaltic contractions are controlled by an intrinsic electrical pacemaker located in the mid-body along the greater curve. This study was undertaken to investigate gastric motility in long-term survivors of neonatal gastric rupture who were surgically deprived of their original pacemaker. Four patients, 1 boy and 3 girls, aged between 6 and 12 years were studied. Physiological activity of the gastric remnant was assessed in terms of electrical as well as peristaltic functions by means of electrogastrography and video-recorded barium swallow study. Electrical and mechanical pacing activities were classified into normogastria or dysrhythmia (brady- or tachygastria) according to their frequencies. In these patients, ectopic pacemakers were found to be arising just distal to the site of resection along the greater curve. Electrophysiologically, one patient was diagnosed as having normogastria, and other 3 patients were found to have dysrhythmia (2, bradygastria; 1, tachygastria) on the basis of electrogastrographic analyses. In two of three patients studied further by fluoroscopy, electrical activity agreed well with peristaltic activity. In one patient, however, electrical tachygastria was associated with peristaltic bradygastria. In conclusion, an ectopic pacemaker arises in the stomach that does not remain silent after neonatal surgical loss of its own pacemaker. Noninvasive electrogastrography seems useful in assessing electrical potentials generated by the ectopic pacemaker.

Induction of CD8+ T cell-mediated protective immunity against Trypanosoma cruzi

Trypanosoma cruzi was transformed with the Plasmodium yoelii gene encoding the circum-sporozoite (CS) protein, which contains the well-characterized CD8+ T cell epitope, SYVPSAEQI. In vivo and in vitro assays indicated that cells infected with the transformed T. cruzi could process and present this malaria parasite-derived class I MHC-restricted epitope. Immunization of mice with recombinant influenza and vaccinia viruses expressing the SYVPSAEQI epitope induced a large number of specific CD8+ T cells that strongly suppressed parasitemia and conferred complete protection against the acute T. cruzi lethal infection. CD8+ T cells mediated this immunity as indicated by the unrelenting parasitemia and high mortality observed in immunized mice treated with anti-CD8 antibody. This study demonstrated, for the first time, that vaccination of mice with vectors designed to induce CD8+ T cells is effective against T. cruzi infection.

Emergence of resistance to acyclovir and penciclovir in varicella-zoster virus and genetic analysis of acyclovir-resistant variants

We have characterized the differential actions of acyclovir and penciclovir against varicella-zoster virus (VZV) in cell culture by comparing the frequency of appearance of resistant viruses followed by their characterization. Cells were infected with cell-free virus and the cultures were successively treated with increasing concentrations of acyclovir or penciclovir. Drug-resistant viruses were selected in the presence of 6 microg/ml of acyclovir or penciclovir. The emergence frequency of resistant viruses was significantly higher following acyclovir exposure than following penciclovir exposure (Fisher's exact test, P<0.0001), possibly reflecting virus growth differences under these experimental conditions. Based on antiviral drug susceptibility and thymidine kinase (TK) activity assays, 11 acyclovir-resistant variants from seven experiments using three virus strains (Kawaguchi strain, Oka varicella vaccine strain and a clinical isolate from a zoster patient) were found to be TK-deficient. Sequence analysis of TK-deficient variants of the Kawaguchi strain revealed deletions that caused frameshifts, resulting in premature termination in the TK gene.

Hemodynamic and hormonal responses to nicorandil in a canine model of acute ischemic heart failure: a comparison with cromakalim and nitroglycerin

The pharmacologic profiles of nicorandil in the cardiovascular system have been characterized by K-channel opening and nitrate activities. However, the effects of nicorandil on acute heart failure have yet to be elucidated. To investigate the effects of nicorandil under such pathophysiologic conditions, we administered nicorandil intravenously to dogs with acute ischemic heart failure induced by coronary embolization and compared the results with those induced by cromakalim and nitroglycerin. The heart failure in this experiment was demonstrated by a reduction of mean blood pressure (MBP) from 143+/-3 to 129+/-2 mm Hg (p < 0.01); cardiac output (CO) from 2.18+/-0.10 to 1.06+/-0.05 L/min (p < 0.01); stroke volume (SV) from 12.7+/-0.6 to 6.8+/-0.3 ml/min (p < 0.01); Vmax, an index of the contractility of the left ventricle, from 105.5+/-4.4 to 49.9+/-1.8 1/s (p < 0.01), and an increase in right atrial pressure (RAP) from 2.9+/-0.3 to 5.3+/-0.3 mm Hg (p < 0.01); left ventricular end-diastolic pressure (LVEDP) from 2.5+/-0.4 to 26.0+/-1.4 mm Hg (p < 0.01); and T, time constant of left ventricular relaxation, from 38.3+/-0.8 to 62.4+/-2.8 ms (p < 0.01). Furthermore, plasma renin activity (PRA) and plasma atrial natriuretic peptide (ANP) increased (from 1.72+/-0.29 to 5.03+/-0.68 ng AngI/ml/h, p < 0.01; from 103.9+/-5.8 to 411.5+/-29.4 pg/ml, p < 0.01, respectively), whereas brain natriuretic peptide (BNP) remained unchanged (from 23.1+/-2.2 to 26.9+/-1.4 pg/ml). Nicorandil (10-40 microg/kg/min, i.v. infusion for 20 min for each dosing) or cromakalim (0.25-1 microg/kg/min) decreased MBP, systemic vascular resistance (SVR), RAP, and LVEDP, and increased CO, SV, and Vmax. However, the reduction of RAP in cromakalim was significantly smaller than those of nicorandil and nitroglycerin in comparison at similar hypotensive doses. Nitroglycerin (2.5-10 microg/kg/min) decreased MBP, RAP, and LVEDP, and increased Vmax but did not change CO or SV. Increased plasma ANP levels, an index of cardiac filling pressure after induction of acute ischemic heart failure, were decreased significantly by cromakalim and tended to decrease by nicorandil or nitroglycerin. Plasma BNP levels and PRA were not influenced by any of these drugs. These results suggest that nicorandil produces the reduction of both preload and afterload followed by an improvement of cardiac contractility in this model. The increase in CO may be mediated mainly by the drug's K-channel opening activities and the reduction of venous tone by its nitrate properties. Nicorandil may prove to be useful in the treatment of acute ischemic heart failure.

Antipyretic activity of cinnamyl derivatives and related compounds in influenza virus-infected mice

Kakkon-to is composed of seven medicinal herbs and exhibited novel antipyretic activity by suppressing interleukin-1alpha production responsive to interferon in a murine intranasal influenza virus infection model. Using this model, antipyretic compounds with such novel biological activities were characterized from the herbs. The organic solvent-extractable fractions of Cinnamomum cassia among the herbs showed antipyretic activity. We selected six antipyretic compounds from 48 cinnamyl derivatives and related compounds that may be mainly involved in the fractions. Their antipyretic activity was significantly correlated with interleukin-1alpha regulatory activity. Four of them suppressed interleukin-1alpha production to a basal level and showed different mode of antipyretic action from that of aspirin in interleukin-1alpha-injected mice. Structure-bioactivity relationship of the four suggested that an ester bond played an important role for both antipyretic and interleukin-1alpha regulatory activities. These compounds may be useful in analyzing interleukin-1alpha-producing cells in fever production and the mechanism of defervescence by suppressing interferon-induced interleukin-1alpha production.

A live non-neurovirulent herpes simplex virus vector expresses beta-galactosidase in the nervous system of the Wistar and Sprague-Dawley strain rat for a prolonged period

We have constructed a live non-neurovirulent herpes simplex virus vector expressing beta-galactosidase under the control of the latency associated transcript promoter without inducing inflammation. Pathogenicity of the recombinant virus (betaH1) was not observed in the cutaneous, intravenous and intracerebral infection in mice. When betaH1 was inoculated at the caudate putamen of rats, beta-galactosidase activity was observed in neurons at the inoculation site and its projecting frontal cortex. Expression of beta-galactosidase was observed in the neurons of the innervating dorsal root ganglia 45 days after inoculation of betaH1 into the hind paws of the rats. Neither inflammation nor tissue destruction was observed in both neural tissues in this study. Thus this non-neurovirulent recombinant virus is a suitable vector for expressing the foreign genes in the nervous system for the prolonged period.

Suppression of in vitro IFN-gamma production by spleen cells of Plasmodium chabaudi-infected C57BL/10 mice exposed to dexamethasone at a low dose

After infection with Plasmodium chabaudi, C57BL/10 mice produced significant amounts of serum IFN-gamma, developed a low level of parasitemia and survived the infection. Production of IFN-gamma was also obvious when spleen cells of the infected mice were stimulated with the parasite antigen contained in an erythrocyte lysate in vitro. Depletion of CD4+ T cells abrogated production of IFN-gamma, leading to loss of resistance to the infection. The CD4+ T cells/IFN-gamma-dependent resistance of the C57BL/10 mice against P. chabaudi was applied to assess immunotoxicological effect of dexamethasone (DEX). Administration of a high dose (0.75 mg/kg) resulted in loss of the splenic cellularity, remarkable decrease in serum IFN-gamma production, increased level of parasitemia, and eventual death of the infected mice. In contrast, DEX at a low dose (0.02 mg/kg) induced no alternation in the in vivo host immune activity and the mice survived the infection. However, when spleen cells were obtained from the infected mice administered the low dose of DEX and stimulated in vitro with the parasite antigen, a significantly decreased level of IFN-gamma was demonstrated with compared to control mice. These findings demonstrate that the in vitro production of IFN-gamma by spleen cells from P. chabaudi-resistant C57BL/10 mice was more sensitive to the immunosuppressive effect of in vivo administration of DEX. This ex vivo assay might provide a method for evaluation of drug-induced immunotoxicity at a higher sensitivity than the conventional host resistant assays such as comparison of severity of disease or time to death.

Partial protection of severe combined immunodeficient mice against infection with Babesia microti by in vitro-generated CD4+ T cell clones

Because CD4+ T cells were considered to be involved in protection against infection with Babesia microti, specific CD4+ T cells were generated in vitro from recovered BALB/c mice and their protective activity was tested in vivo. The cells produced varying amounts of interferon (IFN)-gamma in vitro in response to parasite antigen. In passive transfer experiments, three out of eleven T cell clones tested exerted protective activity in the early phase after infection. However, there seemed to be no correlation between this protection and in vitro IFN-gamma production by the T cell clones. Although the protection was partial and short-lived, the result provided direct evidence that CD4+ T cells play a crucial role in defense against B. microti.

Hepatocyte growth factor enhances the invasion activity of human hepatocellular carcinoma cell lines

We investigated whether hepatocyte growth factor (HGF) enhances the invasion activity of three human HCC cell lines, HLF, HLE, and HC-4, in vitro. The analysis of the invasiveness consisted of the production of u-PA and the chemotaxis for fibronectin. Invasion activity of all cell lines was enhanced by the addition of recombinant human hepatocyte growth factor (rhHGF) to the medium. HGF stimulated the production of u-PA in HLF cells. HGF accelerated the chemotaxis of HC-4 and HLE. These data suggest that HGF increase the invasion activity of human HCC cell lines by affecting the production of u-PA or the chemotaxis for fibronectin.

Coronary artery-pulmonary artery fistula originating from three major coronary branches associated with exertional chest pain and tachycardia-dependent left bundle branch block

A 49-year-old male was admitted to our hospital because of chest pain. The pain occurred simultaneously with tachycardia-dependent left bundle branch block (LBBB) during exercise-stress and atropine-stress electrocardiogram (ECG) and on 24-h ambulatory ECG monitoring. Myocardial perfusion and metabolic scintigraphy with Tl-201 and I-123 BMIPP, respectively, showed no evidence of ischemia. Coronary arteriography revealed no atherosclerotic lesions, but did show a fistula between three major coronary arteries and the main pulmonary artery. The left-to-right shunt was undetectably small. Administration of diltiazem and metoprolol suppressed LBBB by attenuating the heart rate response to exercise, and reduced the chest pain. Therefore we presume that the exertional chest pain was not caused by myocardial ischemia but by the tachycardia-dependent LBBB. Coronary artery-pulmonary artery fistula is the most common type of coronary artery fistulae found incidentally in adulthood. Involvement of three major coronary branches is, however, rare. The case is discussed with a review of the literature.

Longitudinal changes of metacarpal cortical striation in Graves' disease

RATIONALE AND OBJECTIVES

The authors verify whether metacarpal cortical striation can be used to assess longitudinal changes in bone turnover in Graves' disease.

METHODS

Eight patients with untreated Graves' disease (5 men, 3 women; age 36 +/- 12 years) and six patients with the disease in remission (1 man, 5 women; age 38 +/- 12) were studied. Posteroanterior radiographs of the bilateral hands were obtained using fine-grain mammography film and direct magnification. Three observers independently determined the grade of cortical striation (striation index; SI) of the second and third metacarpals in randomly presented radiographs.

RESULTS

The SI determined by all observers decreased significantly after the beginning of antihyperthyroid therapy compared with the SI before treatment (P < 0.05). Significant correlation was found between the observers' assessments (r = 0.74, P < 0.001). The average kappa value and percent agreement were 0.27 and 51.8%, respectively. Intraobserver variability provided relatively good kappa statistics (kappa: 0.56; percent agreement: 79.9%). Longitudinal decrease in the SI was in accordance with a decline in urinary pyridinoline cross-link excretion, a decline in serum osteocalcin, and an increase in bone mineral density of lumbar spine.

CONCLUSIONS

The change in the SI can be used to detect increased and decreased bone turnover. Thus, the SI can be used as one index of bone turnover in patients with Graves' disease.

Isolation and structural identification of bifidogenic growth stimulator produced by Propionibacterium freudenreichii

A bifidogenic growth stimulator produced by Propionibacterium freudenreichii was purified, and its chemical structure was determined. We obtained 7.1 mg of a bifidogenic growth stimulator from 1738 g of lyophilized P. freudenreichii cells by silica gel column chromatography, Sephadex LH-20 column chromatography, and preparative HPLC. The mass of the bifidogenic growth stimulator was 217.037 (C11H7NO4) as determined by high resolution mass spectrometry. Various experimental analyses indicated that the chemical structure of the bifidogenic growth stimulator was 2-amino-3-carboxy-1,4-naphthoquinone.

Mitogenic stimulation of bovine peripheral blood mononuclear cells by Theileria sergenti antigen and inhibition by antibody from experimentally infected cattle

Stimulation with a lysate of Theileria sergenti-parasitized red blood cells (PRBC) resulted in marked proliferation of normal bovine peripheral blood mononuclear cells (PBMC) in vitro. Partial inhibition of the proliferation was demonstrated by the addition of immunoglobulin (Ig) obtained from experimentally infected cattle when they revealed high levels of parasitemia and antibody titres. A mouse monoclonal antibody recognizing a 32 kDa antigen also showed inhibitory activity against the in vitro proliferation of bovine PBMC, but complete inhibition could not be achieved.

[Clinicopathological study on early recurrent hepatoma and its treatment]

Early Recurrence of Hepatoma: PCNA Labeling Index and DNA Ploidy Pattern Sixty-four cases of recurrent hepatocellular carcinoma (HCC) after hepatectomy were divided into two groups; E-group with recurrence within one year, and L-group with recurrence after 1 year. Clinicopathological features and surgical curability were the same in both groups. E-group had significantly higher positive rates of portal invasion, intrahepatic metastasis and rate of patients with more than 40% on PCNA labeling index. While the similar recurrence mode and the same treatment modalities were done, cumulative survival rates after recurrence in E-group had a poorer prognosis than L-group. These results suggest the possibility of lower response for the treatment on the recurrent lesion would be manifest in the E-group. New modalities for prevention of early recurrence of HCC after resection should be developed.

Enhanced renal susceptibility to ischemia-reperfusion injury in the rat with obstructive jaundice

BACKGROUND/AIMS

To investigate the susceptibility of kidneys to ischemia-reperfusion injury under obstructive jaundice.

MATERIALS AND METHODS

Bile ducts of male rats were ligated for five days, right kidneys were removed, and vascular clamps were placed across left renal arteries for 30 minutes.

RESULTS

Twenty-four hours later, ischemia-reperfusion produced renal injury in jaundiced rats as shown by increased serum creatinine and urea nitrogen levels. Histological observation showed tubular damages. These changes were minimal after ischemia-reperfusion in control rats. Renal thiobarbituric acid reactive substance contents were increased after bile duct ligation, which did not change after ischemia-reperfusion. On the other hand, ischemia-reperfusion produced a significant increase in renal thiobarbituric acid reactive substance contents in control rats. Renal glutathione contents were increased two fold after bile duct ligation and they were significantly decreased by ischemia-reperfusion.

CONCLUSIONS

Kidneys in obstructive jaundice appear to be susceptible to ischemia-reperfusion injury. Although protective roles of GSH is suggested, the role of oxygen radicals in this type of renal injury remains to be further elucidated.

Cyclothialidine analogs, novel DNA gyrase inhibitors

DNA gyrase inhibitors, cyclothialidines B, C, D and E were isolated from four Streptomycete strains (NR 0659, NR 0660, NR 0661 and NR 0662). Their structures have been elucidated based on the amino acid analysis of the hydrolysates, NMR and HRFAB-MS experiments and shown to be cyclothialidine analogs. The absolute stereochemistry has been determined by the chiral HPLC analysis of the hydrolysates. Cyclothialidines B, D and E are novel and potent inhibitors of DNA gyrase.

Autoimmune hepatitis triggered by administration of an herbal medicine

Although herbal medicines are believed to be safe with few side effects, there are several reports on drug-induced liver injury caused by them. However, there are no reports of autoimmune hepatitis triggered by herbal medicines. We report here the case of a patient with autoimmune hepatitis that became clinically apparent after administration of Dai-saiko-to (Da-Chai-Hu-Tang), an herbal medicine that is used as a standard medicine in Japan.

In vitro activation of mouse spleen cells by a lysate of Theileria sergenti-infected bovine red blood cells

A lysate of Theileria sergenti-infected bovine red blood cells induced in vitro proliferation of mouse spleen cells in a 2-3-day incubation period. Experiments using B or T cell-enriched preparations showed that a B cell (B220+ CD3- population) was responsible for this non-specific proliferation. In the culture supernatant of spleen cells stimulated with the lysate, considerable amounts of interleukin 2 (IL-2) and gamma-interferon (IFN-gamma) were revealed after 2 days, followed by production of immunoglobulin with a peak at 4-6 days. Thus, it was suggested that a lysate antigen(s) of T. sergenti-infected red blood cells was able to stimulate mouse spleen cells to produce IL-2 and IFN-gamma, which in turn induced the proliferation of B cells and production of immunoglobulin.

Japanese Biliary Atresia Registry, 1989 to 1994

The Japanese Biliary Atresia Society founded in 1980 for the aim of investigations of all aspects of biliary atresia (BA), started a nationwide registry of BA patients in 1989. A total of 626 cases were registered from 1989 to 1994. The male to female ratio was 0.58. Corrective surgery was performed in 603 patients. Regarding the type of obstruction, 63 cases were Type I, atresia of the common bile duct, 9 were Type II, atresia of the hepatic ducts, and 543 were Type III, atresia of the porta hepatis. As initial corrective procedures, original Roux-en Y, Suruga II and Roux-en Y with intestinal valve were mainly employed. Jaundice cleared in 346 patients (57%) and decreased in 131, while it persisted in 120. The 5-year-follow-up showed that 34 patients, 49% of the patients who were followed up, were alive without jaundice, while 28 (41%) are dead. Thirty five, 33% of the patients who were entered to the Registry, were lost to follow-up.