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H Hara

Publications and source records attributed to H Hara.

At least 451 records · Page 25Linked to original sources
PubMed1993

A temporal model of animal behavior based on a fractality in the feeding of Drosophila melanogaster.

We present a new temporal model of animal behavior based on the ethological idea that the internal states of the individual essentially determine the behavior. The internal states, however, are conditioned by the external stimuli. This model, including environmental and internal parameters, predicts a fractal property of the behavior, that is, an inverse power law distribution of the duration. Being consistent with the model, we have found a fractal property of feeding in Drosophila melanogaster: The dwelling time of starved flies on food showed a clear inverse power law distribution. The dependence of the fractal dimension on the intensity of food stimuli has been observed, and the predicted change into an exponential distribution was proved.

Animals↗
PubMed1993

Osmoregulation of the fatty acid receptor gene fadL in Escherichia coli.

The fadL gene of Escherichia coli codes for an outer membrane protein that is involved in the uptake of long-chain fatty acids. Uptake is regulated by environmental osmolarity, and decreases when the cells are grown under conditions of high osmolarity. A temperature-sensitive mutant that requires fatty acid for growth at 42 degrees C was unable to grow at the high temperature even in the presence of fatty acid if the medium contained 10% sucrose. Promoter activity of the fadL gene in vivo was repressed by high osmolarity in a FadR repressor null mutant. Furthermore, in vitro transcription of the fadL gene was strongly repressed by the addition of OmpR and EnvZ proteins. The results of gel retardation and DNase I protection experiments indicated that OmpR, after incubation with the protein kinase EnvZ, specifically binds to at least four sites around the fadL promoter, two upstream and two downstream from the transcriptional start site. These results suggest that transcription of the fadL gene is osmotically regulated by the OmpR-EnvZ two-component system.

Bacterial Outer Membrane Proteins↗
PubMed1993

Surgery for cholelithiasis in cirrhotic patients.

Although biliary tract surgery for cholelithiasis is performed frequently in Japan, cirrhotic patients require special consideration. Postoperative complications after biliary tract surgery were studied in 23 patients with liver cirrhosis and associated cholelithiasis, 9 of whom had no complications, 8 had minor complications, and 6 had severe complications. Concerning the relation between Child's classification and postoperative complications, no complications were seen in four Child's type A patients, but seven of ten (70%) Child's type B patients and seven of nine (78%) Child's type C patients developed complications. Two (20%) of the Child's type B patients and four (44%) of the Child's type C were severe, and three of the latter group died. Regarding the preoperative laboratory findings, significant differences were seen between the patients without complications and those with severe complications in serum bilirubin, albumin, and ICG R15 values. Of the six patients with severe complications, five had choledocholithiasis, three of whom died of liver failure, while two developed biliary peritonitis caused by insufficient fistula formation after removal of the T-tube. Thus, for the treatment of choledocholithiasis in patients with severe cirrhosis, avoiding surgical invasion through the use of such techniques as endoscopic papillotomy is recommended whenever possible.

Biliary Tract Surgical Procedures↗
PubMed1993

Westernized food habits and concentrations of serum lipids in the Japanese.

To investigate the association of westernized food habits and concentrations of serum lipids in the Japanese, we studied 1200 healthy Japanese living in Hiroshima prefecture and 1483 ethnic Japanese from Hiroshima prefecture living in the Hawaii Islands and Los Angeles. The nutritional assessments were made by the same dietitians. No major difference was observed in the total energy intake between the Japanese and the Japanese-Americans in both males and females. However, the intake of animal fat and simple carbohydrates (especially fructose) were markedly greater, and that of complex carbohydrates lower, in the Japanese-Americans compared with the Japanese. The mean serum cholesterol (CH), LDL-CH and serum triglyceride (TG) levels were significantly higher in the Japanese-Americans in both sexes. The mean HDL-CH concentration was similar between the two groups in males, but it was approximately 7 mg/dl higher in Japanese-American females. Using the 75 percentile values of CH and TG in the Japanese in Hiroshima, the frequency of WHO types IIa and IIb hyperlipidemia was about twice as high in the Japanese-Americans. These results suggest that westernized food habits in the Japanese include qualitative changes in animal fat, simple carbohydrate and complex carbohydrate diet rather than an increase in the total energy intake. These changes are associated with marked increases in the concentrations of serum CH and TG and increased prevalence of types IIa and IIb hyperlipidemia.

Adult↗
PubMed1993

De novo synthesis of phospholipase A2 and prostacyclin production by proliferating rat smooth muscle cells.

We investigated the role of phospholipase A2 (PLA2) in cell cycle-dependent alterations of endogenous prostacyclin (PGI2) synthesis in aortic smooth muscle cells in culture (VSMC) from Wistar Kyoto rats. Randomly cycling VSMC generated more PGI2 than the stationary cells. Cell cycle analysis showed that PGI2 production capacity was increased from the G0/G1 through the early DNA synthetic (S) phases. Enzyme analysis revealed that, although there were different mechanisms underlying this increase in the PGI2 production during the G0/G1, the peak at 4 hours coincided with a sharp increase in PLA2 activity. This increase in PLA2 activity was preceded by an increased expression of functional PLA2 messenger RNA, and protein synthesis inhibition prevented most of the increase in PGI2 production at 4 hours. These data indicate that endogenous PGI2 generation is mainly increased during the G0/G1 period and that this event is secondary to de novo synthesis of PLA2 and probably, at least in part, to cyclooxygenase induction. This mechanism provides a negative feedback regulating VSMC proliferation.

Animals↗
PubMed1993

Effects of a new diphenylpiperazine calcium antagonist, KB-2796, on cerebral ischemic neuronal damage in rats.

1. The effects of KB-2796, a new diphenylpiperazine calcium antagonist, on the mitochondrial dysfunction and energy metabolism deficits were examined in the ischemic rat brain. 2. KB-2796 (30 mg/kg, p.o.), administered 60 min prior to decapitation, improved the reduced respiratory activity of mitochondria obtained from rat brain 5 min after decapitative ischemia. 3. KB-2796 (30 mg/kg, p.o.), administered 60 min prior to ischemic insult, improved both the reductions in pyruvate and ATP and prevented increases in the lactate/pyruvate ratio induced by 30-min forebrain ischemia in rats with 4-vessel occlusion (4-VO). 4. The effect of KB-2796 on local cerebral glucose utilization (LCGU) was examined by a quantitative autoradiographic 2-[14C]deoxyglucose method in normal and 4-VO rats. 5. Postischemic LCGU measured 24 hr after reperfusion in the forebrain, in particular in the cortex, thalamus, geniculate body, hippocampus, caudate-putamen, nucleus accumbens, colliculus, and corpus callosum, was below the normal control value. 6. KB-2796 (1 mg/kg, i.v.), administered 1 min prior to the injection of 2-[14C]deoxyglucose, improved the reductions in LCGU that were produced by cerebral ischemia in the cortex, thalamus, geniculate body, caudate-putamen, nucleus accumbens and substantia nigra, but did not affect LCGU in normal rats. 7. These findings suggest that KB-2796 minimized the deficits in brain energy metabolism produced by ischemia; this agent may therefore be a valuable therapeutic drug in cerebrovascular-related disorders.

Animals↗
PubMed1993

Structural study of the N-linked oligosaccharides of hepatocyte growth factor by two-dimensional sugar mapping.

The structures of the N-linked oligosaccharides on recombinant human hepatocyte growth factor (rh-HGF) expressed by Chinese hamster ovary (CHO) cells were studied by two-dimensional sugar mapping. The oligosaccharides released from the glycopeptides by peptide: N-glycosidase F (PNGase F) treatment were tagged with 2-aminopyridine at the reducing ends. The alpha-chain was linked by biantennary, triantennary, and tetraantennary oligosaccharides, but the dominant oligosaccharides linking the beta-chain were biantennary (> 85%). There was no significant difference in oligosaccharide structures between the two glycosylation sites on each chain, that is, Asn263 and Asn371 on the alpha-chain, and Asn535 and Asn622 on the beta-chain. The linkage of sialic acid to the non-reducing terminal galactose was identified as NeuAc alpha(2-3) by 1H-NMR spectrometry. The structures of the N-linked oligosaccharides from rat HGF were also studied. Triantennary oligosaccharides were obtained from the alpha-chain and a biantennary oligosaccharide was obtained from the beta-chain. This result indicates that the alpha-chain is also linked by higher branched oligosaccharides than the beta-chain in rat HGF.

Aminopyridines↗
PubMed1993

Melanin pigments and melanosomal proteins as differentiation markers unique to normal and neoplastic melanocytes.

This report introduces some aspects of our current basic research focus on the unique metabolic pathways within the melanocyte. Using this approach, we hope to gain a better understanding of the pathophysiology of malignant melanoma and develop early laboratory diagnostic tests for this disease. Specifically, we will discuss that: 1) the synthesis of pheomelanin is markedly increased in malignant melanoma and dysplastic melanocytic nevi; 2) high levels of metabolites of pheomelanin and eumelanin can be detected in the urine and blood of patients with metastatic melanoma; 3) this release of melanin metabolites appears to correlate with tumor thickness and tumor load, including the extent of metastasis; 4) the synthesis of melanosomal proteins also becomes aberrant in malignant melanoma; and 5) this abnormal melanosome synthesis can be utilized in the identification of antigenic epitopes that are uniquely expressed in malignant melanoma. We believe that this synthesis and secretion of abnormal melanin pigment and melanosomal proteins (human melanosome-specific antigen) would be useful for the development of early laboratory diagnostic and monitoring tools for malignant melanoma. In addition, we also report the detection of pheomelanin component in "normal" unexposed skin; however, the relative amount of pheomelanin in the skin does not reflect hair color (e.g., red hair). The nature of this pheomelanin component in the skin needs to be further clarified.

Animals↗
PubMed1993

[Pleural washing with povidone-iodine for treatment of empyema].

In this paper, we report two successful cases of empyema treated by pleural washing with povidone-iodine solution. In these two cases, empyema was caused by secondary infection of multi-drug resistant Pseudomonas aeruginosa. First, we replaced intrathoracic drainage tube and washed intrathoracic space with 500-1000 ml saline containing antibiotics (tobramycin, aztreonam) every 8 hours for 10-14 days. But, cultural studies of pleural effusion were positive even after this treatment. So, we tried pleural washing with warm povidone-iodine solution 1:20 diluted with saline every 8 hours. Surprisingly, after 3 days treatment, cultural studies of the pleural effusion became negative. This pleural washing method with povidone-iodine was very effective for treatment of empyema patients.

Aged↗
PubMed1993

Association of Actinobacillus actinomycetemcomitans leukotoxin with nucleic acids on the bacterial cell surface.

Actinobacillus actinomycetemcomitans, a periodontopathic gram-negative bacterium, produces a leukotoxin that is a member of the RTX cytotoxin family. Although genes may function in toxin secretion, the leukotoxin is not secreted extracellularly but remains associated with the bacterial cell surface. We report here that this toxin-cell surface association is mediated by nucleic acids and directly demonstrate that the extracellular secretion of toxin occurs in growing cultures with increased ionic strength of medium. All examinations were performed with freshly harvested A. actinomycetemcomitans 301-b from anaerobic fructose-limited chemostat cultures. The occurrence of cell surface-localized DNA was shown by directly digesting whole cells with the restriction endonuclease EcoRI or HindIII, which yielded many DNA fragments. The cell surface DNA constituted about 20% of the total cellular DNA. The leukotoxin was released from the whole cells by digestion with DNase I as well as restriction endonucleases. Because the leukotoxin binds ionically to DNA, it is dependent on the ionic strength of buffers or media. Accordingly, the toxin was released from cells suspended in saline at pH 7.5 in the presence of increasing amounts of MgCl2 (0 to 10 mM) or NaCl (0 to 50 mM). Moreover, a considerable quantity of leukotoxin was detected in the culture supernatant of fructose-limited chemostat cultures when sodium succinate solution was pumped into the steady state as an additional salt (30 and then 50 mM). This toxin-DNA association was also found in well-characterized strains including not only the leukotoxin-producing ATCC 29522 but also the toxin production-variable ATCC 29523 and the non-leukotoxin-producing ATCC 33384 when these strains were grown in the chemostat culture.

Aggregatibacter actinomycetemcomitans↗
PubMed1993

Diffuse panbronchiolitis: follow-up CT examination.

PURPOSE: The authors reviewed serial computed tomographic (CT) scans obtained in 19 patients with diffuse panbronchiolitis (DPB) to evaluate changes in disease pattern over time. MATERIALS AND METHODS: Nineteen patients with DPB were entered into the study. After initial CT examination, 12 patients were randomly assigned to receive long-term low-dose (200 mg three times daily) erythromycin therapy; seven patients received no treatment. RESULTS: Follow-up CT scans revealed that centrilobular areas of high attenuation observed initially had progressed to dilatation of the proximal airway in some patients in the untreated group. In the treated group, the centrilobular and branched linear areas of high attenuation were decreased in number and size, although the airway dilatation and decreased lung attenuation in the peripheral areas remained unchanged or were slightly increased. CONCLUSION: CT scans are valuable in the study of the disease process and response to therapy in DPB.

Adult↗
PubMed1993

Parasympathetic cerebrovascular innervation: an anterograde tracing from the sphenopalatine ganglion in the rat.

To elucidate parasympathetic cerebrovascular innervation of the rat sphenopalatine ganglion (SPG), we injected wheat germ agglutinin-conjugated horseradish peroxidase into the SPG of one side and traced anterogradely labeled nerve fibers. Three days after the injection, the animals were killed and tissues including the SPG, major cerebral arteries, and ethmoidal arteries were reacted by the tetramethylbenzidine method. A number of cells and nerve fibers labeled with wheat germ agglutinin-conjugated horseradish peroxidase were observed in the SPG. The nasal mucous membrane, the periorbital soft tissue, and the lacrimal gland of the injected side contained numerous labeled nerve fibers. In cerebral vessels, anterogradely labeled nerve fibers were observed around the internal ethmoidal, anterior cerebral, middle cerebral, internal carotid, and posterior cerebral arteries of both sides. A few labeled nerve fibers were seen on the wall of the basilar arteries of the distal portion, and the vertebral arteries contained no labeled nerve fiber. In animals of which the ethmoidal nerve and the external ethmoidal artery were cut together with the surrounding periorbital soft tissues just before entering the ethmoidal foramen, no labeled nerve fiber was identified on the wall of the major cerebral arteries. Although labeled gangliocytes were found in the trigeminal and superior cervical ganglia after the tracer injection to the ipsilateral SPG, the chronic maxillary neurotomy and superior cervical ganglionectomy did not alter the distribution of the labeled nerve fibers on the wall of the cerebral arteries.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1993

Distribution patterns of sensory innervation from the trigeminal ganglion to cerebral arteries in rabbits studied by wheat germ agglutinin-conjugated horseradish peroxidase anterograde tracing.

Distribution patterns of sensory nerves from the trigeminal ganglion to cerebral arteries in rabbits were studied by the wheat germ agglutinin-conjugated horseradish peroxidase anterograde tracing technique along with the 3,3',5,5'-teramethylbenzidine method. Labeled sensory nerves were densely distributed in whole-mount specimens of cerebral arteries after the injection of wheat germ agglutinin-conjugated horseradish peroxidase into the trigeminal ganglion. The characteristics of the innervation in rabbits included: 1) cerebrovascular sensory nerves were more dense in the ipsilateral side than in the contralateral side; 2) the anterior cerebral artery was less densely innervated than the posterior cerebral artery; 3) labeled nerves on the proximal segment of arteries were more prominent than those on the distal segment. The smallest pial branches of the middle cerebral, posterior cerebral, and anterior inferior cerebellar arteries overlying the fine sensory nerves were 50, 75, and 80 microns in diameter, respectively. Two patterns of the sensory innervation were seen. A meshwork pattern was mainly observed in the circle of Willis and the proximal segments of its main branches, as well as in the upper two thirds of the basilar artery; a parallel or slightly twisted pattern was shown in the small pial arterioles. Our results in this study may be useful to understand better the trigeminocerebrovascular system.

Animals↗
PubMed1993

Effect of KB-2796, a new diphenylpiperazine Ca2+ antagonist, on glutamate-induced neurotoxicity in rat hippocampal primary cell cultures.

The effects of the novel calcium channel antagonist KB-2796, other calcium channel antagonists, an N-methyl-D-aspartate (NMDA) antagonist, non-NMDA antagonists, Mg2+, a Ca(2+)-chelator and a calcium channel agonist on neurotoxicity induced by a 10-min application of 100 microM glutamate were studied in rat hippocampal primary cell cultures. KB-2796 (0.1 and 1 microM), flunarizine (1 microM), nimodipine (10 microM), MK-801 (0.01-1 microM), Mg2+ (10 mM) and EGTA (10 mM) significantly prevented the neurotoxicity, but 6-cyano-7-nitro-quinoxalinedione (CNQX) (10 microM) and 6, 7-dinitro-quinoxalinedione (DNQX) (10 microM) did not. Bay K 8644 (10 and 100 nM) enhanced the neurotoxicity. These findings indicate that KB-2796 protects the neuronal cell from the glutamate-induced neurotoxicity, presumably by blocking the Ca2+ influx into brain neurons.

Animals↗
PubMed1993

Effect of lactosucrose (4G-beta-D-galactosylsucrose) on fecal flora and fecal putrefactive products of cats.

The effects of lactosucrose (4G-beta-D-galactosylsucrose) on fecal flora and fecal putrefactive products were studied in 3 Himalayan and 5 Persian cats fed 175 mg of lactosucrose/each/day for 2 weeks. During lactosucrose administration, the counts of lactobacilli increased significantly (p < 0.05), whereas the counts of clostridia, including Clostridium perfringens and Enterobacteriaceace decreased significantly (p < 0.05). The levels of fusobacteria and staphylococci were decreased significantly (p < 0.01) on day 7 of lactosucrose administration, while the counts of bacteroides increased significantly (p < 0.05) and day 14 of lactosucrose administration compared to pre-administration. In frequency of occurrence, bifidobacteria increased significantly (p < 0.001) during lactosucrose administration, while Spirochaetaceae and lecithinase-negative clostridia decreased significantly (p < 0.05) on day 14 of lactosucrose administration compared to pre-administration. No detectable change occurred in the counts of other organisms throughout the experimental periods. Fecal concentrations of ammonia, indole, ethylphenol, and urinary ammonia were reduced significantly (p < 0.05) on day 14 of lactosucrose administration. The water content and weight of the feces increased slightly during lactosucrose administration, but the pH values decreased slightly. The environmental ammonia and the fecal odor also decreased remarkably (p < 0.01) during administration.

Animals↗
PubMed1993

Plasma polymorphonuclear elastase in patients with hyperthyroidism.

We studied plasma polymorphonuclear elastase (PMNE) levels before and during methimazole treatment in patients with hyperthyroidism. Plasma PMNE levels in patients with hyperthyroidism were significantly higher than those of normal subjects and patients with thyroid adenoma. Plasma PMNE levels in patients with Graves' disease were significantly reduced when their thyroid functions after methimazole treatment were normal, compared with the levels of the patients before treatment. In patients with hyperthyroidism there was a significant positive correlation between plasma PMNE and serum FT3, but no correlation between plasma PMNE and serum TRAb. The results suggested that PMNE was secreted from blood neutrophil in hyperthyroid state patients with Graves' disease and that it was beneficial for helping determining peripheral thyroid function.

Adenoma↗
PubMed1993

[Difference in perceived health between blue- and white-collar workers of a manufacturing factory by a self-administered questionnaire].

In order to examine the differences in which blue- and white-collar workers perceive their own health status, a survey using self-administered questionnaire was conducted. The subjects were 1,428 male workers in a tire manufacturing factory, consisting of 1,185 blue-collar workers and 243 white-collar workers. Most of the blue-collar workers were engaged in shift work consisting of three shifts/d. The questionnaire included 32 items concerning health habits, life and job satisfaction, mental stress, and type A behavior. The following findings were obtained. Good daily health habits were related to age. Older workers had better health habits than the younger ones both in white- and blue-collar workers. The white-collar workers were more satisfied with their life and jobs, and also showed type A behaviors at a higher rate. As for fatigue and dissatisfaction association with shift work, the workers' complaints increased in the order of day shift, evening shift and midnight shift. The older workers had fewer complaints than the younger ones. These results suggested that health management and education will be more effective if the working conditions and the background of each worker are taken into consideration.

Adult↗