Safety and efficacy of oral flecainide acetate in patients with cardiac arrhythmias

We retrospectively studied the clinical efficacy and safety of oral flecainide in 38 patients with symptomatic arrhythmias. Patients received 100 to 200 mg daily of flecainide for a mean of 25 months (range 8 to 50 months). All patients had normal cardiac function. Paroxysmal atrial fibrillation (PAF) was observed in 29 patients (76%). Other forms of arrhythmia included paroxysmal atrial flutter, seen in 3 patients (8%); premature atrial contraction and ventricular premature contraction, each seen in 2 patients (5%); and supraventricular tachycardia and ventricular tachycardia, each seen in 1 patient (3%). A complete response was obtained in 15 (52%) of 29 patients with PAF and a partial response in 8 patients (27%). The remaining 6 patients (21%) showed no response. A complete response was also obtained in 7 of 9 patients with other forms of arrhythmia. There were no differences in cardiac function and ECG parameters before and after treatment. Flecainide was withdrawn in 4 patients due to the development of electrocardiographic abnormalities. Three of these patients showed an atrial proarrhythmic effect. Abnormal ST elevations in the precordial leads were observed in 1 patient who received 200 mg of flecainide daily. In conclusion, flecainide was effective treatment for supraventricular and ventricular arrhythmias, but attention must be paid to the drug's potential proarrhythmic adverse effects.

A case of epithelioid hemangioendothelioma associated with an artery

We report a case of epithelioid hemangioendothelioma (EHE) arising in the left elbow of a 67-year-old woman. The tumor was characterized by centrifugal growth and association with the brachial artery, causing complete occlusion. Immunohestochemical and electron microscopical features were typical of EHE. The patient was free of local recurrence or disease metastasis for more than 3 years after tumor resection, but subsequently died of respiratory failure due to a primary lung cancer.

Effects of low-dose phenytoin administered to newborn mice on developing cerebellum

To examine correlations between dose levels of phenytoin (PHT) and neurotoxic effects on cerebellar development, we administered 10, 17.5, 25, and 35 mg/kg PHT suspended in sesame oil orally to newborn Jcl:ICR mice once a day during postnatal days 2-4 and determined plasma PHT concentrations during the administration period. Mortality rates were 12.5% and 35.2% in males and 15.3% and 33.3% in females for the 25 and 35 mg/kg PHT-treated groups during the PHT treatment, respectively. In the 25 and 35 mg/kg PHT-treated groups, total brain weight, the size of the cerebellum, and cerebellar weight were significantly reduced on postnatal day 21. However, in the 10 and 17.5 mg/kg PHT-treated groups, total brain weight and the size and weight of the cerebellum did not differ from those of the control group. Histologically, the number of pyknotic cells in the external granular layer (EGL) in the 25 and 35 mg/kg PHT-treated groups was increased on postnatal day 5, and the EGL was thicker than in the control group on postnatal day 14. Some of the Purkinje cells in the 35 mg/kg PHT-treated group showed degeneration. Plasma PHT levels were 10.7 +/- 2.2 and 24.6 +/- 2.6 micrograms/ml in the 25 and 35 mg/kg PHT groups on the third day of PHT treatment, respectively. In the 25 mg/kg PHT group, plasma PHT level was found to be in the therapeutic range for humans, 10-20 micrograms/ml. Accordingly, during pregnancy, epileptic women should be carefully given PHT at the lowest effective dose while plasma PHT levels are monitored properly. These findings emphasize the importance of pharmacokinetics in evaluating of phenytoin-induced developmental neurotoxicity.

Asymmetrical regulation of blood pressure in the rat medulla

The effects of microinjection of serotonin-1 (5-HT1) antagonist methiothepin and 5-HT1 agonist buspirone into the nucleus reticularis parvocellularis were investigated in the anaesthetized rats. Methiothepin produced an increase in arterial blood pressure when injected into the left side, but it did a decrease when injected into the right side. On the contrary, buspirone produced a decrease in arterial blood pressure when injected into the left side, but it did an increase when injected into the right side. These findings provide the clue to clarify that there is a reciprocal regulation of arterial blood pressure between the left and right sides in the rat medulla.

Prevalence of Mycoplasma genitalium in asymptomatic men in Japan

We aim to clarify the prevalence of Mycoplasma genitalium in asymptomatic men in Japan. First-catch urine specimens were obtained from 187 asymptomatic Japanese men and examined for the presence of M. genitalium using a polymerase chain reaction (PCR)-based assay. Two (1.1%) of 187 first-catch urine specimens were positive for M. genitalium. The prevalence of M. genitalium in urine specimens of asymptomatic men in Japan is lower than that in asymptomatic men in the UK (6%) and Denmark (9%).

Esophageal metastasis from prostate cancer: diagnostic use of reverse transcriptase-polymerase chain reaction for prostate-specific antigen

An extremely rare case of esophageal metastasis from prostate cancer is reported. A 65-year-old man presented with anorexia and back pain. Upper gastrointestinal X-ray fluoroscopy and endoscopy revealed a shallow longitudinal ulcer, with converging mucosal folds, approximately 5 cm above the esophagogastric junction. The histological diagnosis of the biopsied specimen was adenocarcinoma. Blood biochemistry revealed elevated serum prostate-specific antigen (PSA) and gamma-seminoprotein levels. Ultrasonography of the prostate disclosed a hypoechoic lesion in the left lobe, and needle biopsy led to the diagnosis of prostatic adenocarcinoma. Since there was no finding suggestive of a primary lesion, apart from that in the prostate, we conducted reverse transcriptase-polymerase chain reaction (RT-PCR) for PSA. PSA-positive mRNA was demonstrated in the tissue of the esophageal tumor. There are three reports on metastasis to the esophagus from prostate cancer, but this is the first case of esophageal metastasis from prostate cancer without any evidence of metastasis to other organs. The importance of RT-PCR for the diagnosis of primary lesions of metastatic cancer is discussed.

Rapid screening of point mutations of the Neisseria gonorrhoeae parC gene associated with resistance to quinolones

To detect quinolone resistance-associated mutations within the Asp-86, Ser-87, Ser-88, and Glu-91 codons of the Neisseria gonorrhoeae parC gene, we developed a rapid and simple assay based on amplification of the regions of the parC gene containing the mutations sites by PCR and digestion of the PCR products with restriction enzymes. By using the method of primer-specified restriction site modification, artificial SalI, PstI, EcoRI, and HinfI restriction sites were created in the regions containing the Asp-86, Ser-87, Ser-88, and Glu-91 codons, respectively. The mutations generating alterations at Asp-86, Ser-87, Ser-88, and Glu-91 were detected as failures of SalI, PstI, EcoRI, and HinfI to digest the respective PCR products. Fifty-five clinical strains of N. gonorrhoeae were examined for mutations in the parC gene by this assay. Appropriate mutations at either the Asp-86, Ser-87, Ser-88, or Glu-91 codon were detected in each of 11 strains in which a mutation had previously been observed by DNA sequencing. This rapid and simple assay could be a useful device for screening genetic alterations in the parC gene associated with resistance to quinolones in N. gonorrhoeae.

Terminology of developmental abnormalities in common laboratory mammals (version 1)

This paper presents the first version of an internationally-developed glossary of terms for structural developmental abnormalities in common laboratory animals. The glossary is put forward by the International Federation of Teratology Societies (IFTS) Committee on International Harmonization of Nomenclature in Developmental Toxicology, and represents considerable progress toward harmonization of terminology in this area. The purpose of this effort is to provide a common vocabulary that will reduce confusion and ambiguity in the description of developmental effects, particularly in submissions to regulatory agencies worldwide. The glossary contains a primary term or phrase, a definition of the abnormality, and notes, where appropriate. Selected synonyms or related terms, which reflect a similar or closely related concept, are noted. Nonpreferred terms are indicated where their usage may be incorrect. Modifying terms used repeatedly in the glossary (e.g., absent, branched) are listed and defined separately, instead of repeating their definitions for each observation. Syndrome names are generally excluded from the glossary, but are listed separately in an appendix. The glossary is organized into broad sections for external, visceral, and skeletal observations, then subdivided into regions, structures, or organs in a general overall head to tail sequence. Numbering is sequential, and not in any regional or hierarchical order. Uses and misuses of the glossary are discussed. Comments, questions, suggestions, and additions from practitioners in the field of developmental toxicology are welcomed on the organization of the glossary as well as on the specific terms and definitions. Updates of the glossary are planned based on the comments received.

Effects of coffee cherry on the activation of splenic lymphocytes in mice

We previously observed that the ingestion by mice of a hot water extract (CC) and the methanol-extracted and water-soluble fraction (CC-W) of coffee cherry, the residue remaining after the removal of coffee beans from the fruit, enhanced the differentiation of thymocytes and the activation of peripheral T-lymphocytes; and the anti-mammary tumour effects of coffee cherry extract was considered to be associated with this immunomodulation. To study further these effects, mitogen response and some immune parameters were examined in a high mammary tumour strain of SHN mice. While the T-lymphocyte response to concanavalin A was not significantly changed by either CC or CC-W, the lipopolysaccharide response was significantly enhanced by both treatments. The proportion of CD45R/B220+ (B) cells in the splenic lymphocytes was significantly increased by CC, and the percentage of activated (CD25+) cells in B-lymphocytes was increased by CC and CC-W. These data indicate that coffee cherry extract can enhance B-lymphocyte response, and suggest that this immunopotentiation contributes to the antitumourigenic role of coffee cherry.

Comparison of urinary component levels in 4 strains of mice with different physiological characteristics

Changes in urinary component levels before, during and after reproduction were examined with 1H-nuclear magnetic resonance (NMR) in four strains of female mice with different mammary tumour potential and related characteristics (SHN, SLN, GR/A and C3H/He). Regardless of the variations in these changes among the strains, the urinary component levels reflected physiological changes during reproduction and some strain-specific characteristics. The urinary excretion of citrate, 2-oxoglutarate and lactate increased from the virginal stage to pregnancy and declined during lactation in all strains, indicating a marked change in sugar metabolism during reproduction. SHN and SLN, which are from the same basal stock, showed a similar pattern and the level, of several components were lower than those of GR/A and C3H/He. The levels of some lower components were compensated for by higher urine excretion. The levels of taurine and betaine, both essential for fetal and pup growth, increased at lactation in only GR/A, reflecting the poorer pup growth observed in this strain. Finally, the 1H-NMR method was useful to estimate not only the metabolic but also the physiological changes of the animals without invasion, pain or distress and would thus contribute to animal welfare in the animal experiments.

Alterations in the GyrA subunit of DNA gyrase and the ParC subunit of topoisomerase IV in quinolone-resistant clinical isolates of Klebsiella pneumoniae

We determined a partial sequence of the Klebsiella pneumoniae parC gene, including the region analogous to the quinolone resistance-determining region of the Escherichia coli gyrA gene, and examined 26 clinical strains of K. pneumoniae for an association of alterations in GyrA and ParC with susceptibilities to quinolones. The study suggests that in K. pneumoniae DNA gyrase is a primary target of quinolones and that ParC alterations play a complementary role in the development of higher-level fluoroquinolone resistance.

Cloning of the cDNA encoding rat Presenilin-1

We isolated rat presenilin-1 (PS-1; also called S182 previously) cDNA from total brain RNA by using a reverse transcription-polymerase chain reaction (RT-PCR) technique with primers homologous to the conserved sequences of human and mouse PS-1. Rat PS-1 cDNA encoded 468 amino acids (aa) and the deduced aa sequence was highly homologous to those of the human (88.4%) and mouse (92.7%). Northern blot analysis of the rat PS-1 cDNA revealed two mRNA species in rat neurotypic pheochromocytoma and glioma cell lines (PC-12 and C6, respectively) that migrated at rates corresponding to approximately 3.0 and 7.5 kb.

Mutations in a hydrophilic part of the core gene of hepatitis C virus in patients with hepatocellular carcinoma in China

We investigated the association between hepatocellular carcinoma (HCC) and the genomic characteristics of the hepatitis C virus (HCV) isolated from residents of the inshore region of the Yangtze River, an area that has one of the highest incidence of HCC in China. We determined the genomic heterogeneity of HCV, and the sequence divergence of the HCV core gene in individuals with chronic hepatitis and HCC. HCV genotype II was predominant among these isolates, which were homologous to other Chinese and Japanese HCV isolates. The rate of nucleotide substitutions in the core gene was significantly greater for isolates from HCC patients than for those from individuals with chronic hepatitis. The nucleotide substitutions were unevenly scattered along the core gene; a cluster of missense mutations was apparent in the region encoding the second hydrophilic domain of the core protein. The rate of occurrence of missense mutations per nucleotide substitution was significantly greater in this clustering variable region (CVR) of the core gene than in the remaining core gene sequence. These observations suggest that mutations in the CVR may be involved in the pathogenesis of chronic HCV infection during hepatocellular carcinogenesis.

Antimicrobial activity of a new fluoroquinolone, DU-6859a, against quinolone-resistant clinical isolates of Neisseria gonorrhoeae with genetic alterations in the GyrA subunit of DNA gyrase and the ParC subunit of topoisomerase IV

The in-vitro antimicrobial activity of DU-6859a, a new fluoroquinolone, was tested against 55 clinical isolates of Neisseria gonorrhoeae. The MIC of DU-6859a inhibiting 90% (MIC90) of the isolates with genetic alterations of both the GyrA subunit of DNA gyrase and the ParC subunit of topoisomerase IV was 0.125 mg/L. The MIC90 for isolates with alterations of GyrA alone or without alterations of GyrA or ParC was 0.03 mg/L and 0.004 mg/L, respectively. The potency of DU-6859a against clinical isolates bearing genetic alterations associated with quinolone resistance was significantly greater than that of currently available fluoroquinolones.

Cytotoxic effect of sodium nitroprusside on PC12 cells

To investigate the biochemical mechanism responsible for NO-induced neurotoxicity, the effect of sodium nitroprusside(SNP), a NO-generating agent, on PC12 cells was studied. The cell density was dose-dependently inhibited by SNP. Neuronally differentiated PC12 cells showed a higher resistance to SNP than the undifferentiated cells. The inhibitory effect was enhanced by 8-Br-cGMP, and reduced by methylene blue. However, 8-Br-cGMP alone had no significant cytotoxicity. SNP also inhibited [3H]-thymidine incorporation into the cells in a dose-dependent manner. The dose response curves for reducing cell density and for inhibiting thymidine incorporation, were found to be virtually superimposable. These results suggested that cytotoxicity elicited by NO seemed to be due to inhibition of DNA synthesis in PC12 cells.

[Apolipoprotein E genotype as a risk factor in Japanese patients with early-onset and late-onset Alzheimer's disease]

Recent studies have provided evidence of an association of apolipoprotein E (apoE) epsilon 4 allele and late-onset sporadic Alzheimer's disease (AD). Some studies have shown the possibility that apoE epsilon 4 is a risk factor of developing AD in early-onset type. We have analyzed the apoE gene polymorphism in a sample of 310 Japanese AD subjects and 237 age-matched Japanese controls. We divided the sporadic AD patients into two subgroups of 237 late-onset (> 65 years) and 73 early-onset (< or = 65 years) patients, and into three subgroups according to their apoE genotype, no epsilon 4, one epsilon 4, and two epsilon 4 alleles. Our data confirmed an association between epsilon 4 allele and early-onset AD and late-onset AD. The odds ratios (95% confidence interval) referred to no epsilon 4 allele for AD were 3.4 (1.7-7.0) for one epsilon 4 allele and 20.3 (2.5-166.6) for two epsilon 4 alleles in early-onset type, and 6.7 (3.9-11.3) for one epsilon 4 allele and 19.0 (2.5-145.6) for two epsilon 4 alleles in late-onset type. These ratios were significantly increased in both early-onset AD and late-onset AD. Kaplan-Meier survival analysis, which estimates the age of onset for subjects with no, one, and two epsilon 4 alleles in early-onset and late-onset type, revealed a significant dose effect where each additional epsilon 4 allele made the age of onset earlier (p < 0.0001). The age of onset is 9.7 years earlier for two epsilon 4 bearers and 3.9 years earlier for one epsilon 4 bearers than no epsilon 4 bearers in late-onset AD, 2.9 years earlier for two epsilon 4 bearers and 1.4 years earlier for one epsilon 4 bearers than no epsilon 4 bearers in early-onset AD. Moreover, we studied an association between apoE epsilon 2 allele and early-onset AD and late-onset AD. There was a significantly decreased frequency of apoE epsilon 2 allele in patients with late-onset AD (p = 0.026), although the frequency of apoE epsilon 2 was not changed significantly in early-onset AD (p = 0.360). The odds ratios referred to no epsilon 2 allele for AD were 1.9 (0.6-5.7) for one epsilon 2 allele in early-onset type, and 0.4 (0.2-0.9) for one epsilon 2 allele in late-onset type. Our study suggested the difference in the effect of apoE genotype on developing AD between early-onset and late-onset type in Japanese patients.

HLA antigens in patients with severe preeclampsia

The distribution of human leucocyte antigens (HLA) was analyzed in 35 patients with severe preeclampsia and compared with that in the general population in the Niigata district of Japan. The frequency of patients with HLA CW7 was significantly higher than that of the general population of this area (p < 0.05, Chi-square test). The frequency of those with HLA-DR6 (DR6, DR13 and DR14) was also significantly greater compared with the general population (P < 0.05, Chi-square test), while that of those with DR4 was significantly lower (P < 0.05, Chi-square test). The compatibility of HLA antigens in spouses was also analyzed in 20 patient couples and 26 normal fertile couples, and there was no significant difference. Thus it is suggested that HLA antigen systems might be involved in the genesis of preeclampsia.

Stimulation of albumin synthesis in rat hepatocytes by ascites from patients with cirrhosis

Hepatocyte growth factor (HGF), identified in ultrafiltered ascites and plasma from patients with cirrhosis, enhances the DNA synthesis in adult rat hepatocytes cultured at low cell density. This study was carried out to investigate the effect of ascites and plasma from patients with cirrhosis on liver-specific functions such as albumin synthesis in adult rat hepatocytes cultured at confluent-cell density. Ultrafiltered ascites from patients with cirrhosis and its ascitic protein, partially purified by fractionation with ammonium sulfate and gel filtration on Sephadex G-200, stimulated albumin synthesis in a dose-dependent manner in the presence of 10(-8), M dexamethasone. This effect was greater than that of 10(-7) M insulin and similar to that of 10(-7) M dexamethasone, but was additive with that of insulin plus dexamethasone. The molecular weight of the ascitic factor was estimated as 100,000 to 150,000, corresponding to that of HGF purified from cirrhotic ascites. Moreover, the partially purified ascitic factor markedly stimulated DNA and protein synthesis in hepatocytes. These findings suggest that the ascitic factor may act as HGF by stimulating hepatocyte DNA and albumin synthesis in a cell density-dependent manner.

Species difference in protoporphyrin IX accumulation produced by an N-phenylimide herbicide in embryos between rats and rabbits

There was a remarkable species difference in developmental toxicity exhibited by S-53482, an N-phenylimide photobleaching herbicide, between rats and rabbits. S-53482 showed embryolethality, teratogenicity, and growth retardation in rats. In contrast, no developmental toxicity was shown in rabbits. The herbicidal activity of S-53482 is due to the photodynamic action of accumulated protoporphyrin IX (PPIX) as a result of inhibition of protoporphyrinogen oxidase (PPO), which is one of the key enzymes in porphyrin biosynthesis common to both plants and animals as part of chlorophyll and heme synthesis. Some plant PPO inhibitors were reported to inhibit mammalian PPO. Therefore, in a search for a possible link between developmental toxicity and enzyme inhibition, PPIX accumulations presumably resulting from PPO inhibition in rat and rabbit embryos were investigated. The results demonstrated that PPIX concentration was increased in rat embryos by 2 orders of magnitude when compared to that of nontreated embryos. On the other hand, no PPIX was accumulated in rabbit embryos even by treatment with a high dose level of S-53482. It was concluded that the species difference in PPIX accumulation corresponded very well to that of the developmental toxicity exhibited by S-53482.

Bufalin inhibits endothelial cell proliferation and angiogenesis in vitro

We have investigated the effects of bufalin, one of the prominent components in Chinese toad venom, on proliferation of bovine aortic endothelial (BAE) cells and tube formation in three-dimensional type I collagen matrix. In the present study, bufalin potently inhibited the formation of capillary-like tubular networks in a dose-dependent manner. Bufalin also inhibited the proliferation of BAE cells at the same concentration (5 nM) that the tube formation was inhibited. As a potent inhibitor of endothelial cell proliferation, bufalin specifically prevented the entry of BAE cells into the G0/G1 phase of a cell cycle. These findings suggest that in vitro angioinhibitory action of bufalin may be induced by the proliferation inhibition of endothelial cells through the arrest at the G2/M phase of a cell cycle.

Further study on the effects of coffee cherry on spontaneous mammary tumourigenesis in mice: effects of methanol extract

To examine the effective components in the antitumourigenic role of water extract of coffee cherry (CC), and the residue after removal of beans, the dry matter of coffee cherry was extracted repeatedly by 60% methanol and further divided into water-soluble and -insoluble fractions (CC-W and CC-M, respectively). Free access to CC-W (0.25% in tap water) markedly inhibited mammary tumour development in SHN virgin mice, while it had no effect on the growth of normal and preneoplastic mammary glands and established tumours. Associated with this, urinary excretion of some components and intrathymic T cell differentiation were stimulated by the treatment with the CC. CC-W had little affect on the endocrine system, including serum prolactin level, oestrous cycles and endocrine organs, but retarded ovarian degeneration in mice developing mammary tumours. The finding in CC-W were generally similar to those in CC. Fat emulsion of CC-M, which was only checked for mammary tumour growth owing to the limited amount available, showed no effect at the dose level used (0.25% in drinking water). Finally, the previous and the present findings taken together strongly suggest that the effective components of coffee cherry are in the water-soluble fraction.

Tumor necrosis factor-alpha (TNF alpha) enhances cisplatin cytotoxicity to ovarian carcinoma xenografts

Antitumor effect was compared between administration schedule of once a day dosing of cisplatin (DDP) for 2 consecutive days (q40d) with or without TNF alpha. In two controls, TNF alpha or dilutor alone was administered. Against the ovarian carcinoma 2008 cells, DDP given at dose level of daily x 2 (3.5 mg/kg/day q40d) combined with TNF alpha (50 mu g/kg/day) schedule showed 6.08-fold tumor growth delay (TGD) (17.10+/-1.65; P<0.01), produced 3.17-fold greater cell kill [ratio of tumor volume of treated and control groups (T:C)=0.148; P<0.01] and resulted in longer survival [median survival (MS)=166; P<0.01] than DDP alone. These are superior to even high dose DDP (7.0 mg/kg/day x 2d) without TNF alpha administration schedule showing TGD=11.38 days T:C=0.271 and MS=97 days. High dose DDP (7.0 mg/kg/day q40d) with TNF alpha showed further DDP antitumor potency (TGD=29.74+/-2.08, P<0.01), however, this schedule showed only 2.56-fold TGD extension and no improvement was found in survival because of its severe toxicity. TNF alpha did not alter DDP induced systemic toxicity. These data indicate that optimal antitumor activity, tolerance and survival improvement occured on a schedule of low dose DDP combined with TNF alpha, and this has prompted the clinical evaluation of this administration schedule.

Histological changes in rat embryonic blood cells as a possible mechanism for ventricular septal defects produced by an N-phenylimide herbicide

An N-phenylimide herbicide, S-53482, inhibits protoporphyrinogen oxidase, an enzyme common to chlorophyll and heme biosynthesis, and produces embryolethality, teratogenicity [mainly ventricular septal defects (VSD) and wavy ribs], and growth retardation in rats. In order to elucidate the mechanism of the developmental toxicity, in particular VSD, effects of the herbicide on rat embryonic blood cells were investigated histologically at the light and electron microscopic levels at 6, 12, 24, 36, and 48 h after oral administration of the chemical to pregnant rats on day 12 of gestation, the most sensitive day for toxicity. Electron and light microscopy demonstrated mitochondrial lesions, including abnormal iron deposits that were probably due to inhibition of heme biosynthesis, in erythroblasts derived from the yolk sac. Subsequently, degeneration of these erythroblasts occurred followed by erythrophagocytosis. Histologically hearts from exposed embryos had a thin ventricular wall, which may reflect a compensatory reaction to a loss of embryonic blood cells. Thus, the herbicide may induce VSD due to hematological dysfunction caused by the inhibition of heme biosynthesis rather than by direct injurious effects on the heart.