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Biomedical subjects

H Tani

Publications and source records attributed to H Tani.

At least 55 records · Page 3Linked to original sources
PubMed1998

Expression of target genes by coinfection with replication-deficient viral vectors.

An in vivo transcription system was developed by coinfection of cells with replication-deficient viral vectors. Recombinant baculovirus (AcT7HCVLuc) and fowlpox virus (FPVT7HCVLuc) carrying a cDNA of the hepatitis C virus (HCV) minigene encoding the HCV 5' untranslated region (UTR), a luciferase gene and the 3' UTR, including the 98 nt extra sequence, under the control of the T7 promoter were constructed. The HCV minigene was synthesized in various cells by coinfection with one of these two viruses and recombinant baculovirus (AcCAT7) or adenovirus (AdexCAT7) expressing T7 RNA polymerase under the control of a mammalian promoter. Only a low level of luciferase expression was obtained in cells coinfected with AcT7HCVLuc and either AcCAT7 or AdexCAT7. In contrast, high-level luciferase expression was detected when the same cells were coinfected with FPVT7HCVLuc and either AcCAT7 or AdexCAT7. We further constructed a recombinant fowlpox virus with its HCV minigene extended to contain the whole HCV core protein region. Significantly high levels of expression of HCV core protein were detected in MT-2, COS7 and Vero cells by coinfection with the recombinant fowlpox virus and AdexCAT7. A coinfection system consisting of recombinant fowlpox virus and AdexCAT7 was established for high level of expression of a target gene in various cells.

Adenoviridae↗
PubMed1998

Pharmacological properties of traditional medicines. XXIV. Classification of antiasthmatics based on constitutional predispositions.

It is commonly accepted that bronchial asthma or rhinitis accompanies disorders in body fluids and body temperature. The effects of ephedrine and the traditional antiasthmatics "Makyo-kanseki-to" and "Goko-to" were therefore studied on such constitutional predispositions as insensible perspiration and body temperature. Ephedrine markedly increased body temperature and exhibited a strong increased action on respiratory insensible perspiration, whereas Makyo-kanseki-to and Goko-to not only prevented the elevation of body temperature, but also increased respiratory insensible perspiration following the reduction of non-evaporative heat loss from the body surface. Thus, the diagnostic criteria of these two medicines used to treat hot-type asthma or dry cough were experimentally determined. The results also suggest that there is a great possibility that the administration of antiasthmatics may elicit side effects or make diseases worse unless their actions on constitutional predispositions are taken into account, such as body temperature and body fluids.

Amygdalin↗
PubMed1998

A new experimental device for the measurement of moisture emission and heat release from respiratory organs and body surface.

A new experimental device was developed to investigate respiratory diseases. The moisture and heat released from respiratory organs and the body surface of a rat were determined by means of this device as well as the rectal temperature. The high recovery of results was statistically confirmed, and the measured values at various environmental temperatures were significantly different from each other. Some standard drugs, such as ephedrine, aminophylline and chlorpromazine, were examined. Their stimulant or depressant actions were clearly observed. The results of some traditional medicines for the treatment of rhinitis and bronchial asthma from this measuring system were consistent with their clinical applications. These results suggest that this new experimental system is not only effective in the experimental understanding of cold-hot syndrome, but also contributes to the evaluation of the effects of traditional medicines.

Animals↗
PubMed1998

Correlation between initial potentials on a signal-averaged P-wave and indice of electrophysiologic measurements in the right atrium.

The aim of this study was to determine whether initial potentials of the P-wave on a signal-averaged electrocardiogram (SAE) during sinus rhythm reflect indices of electrophysiologic measurements in the high lateral right atrium. A total of 67 patients underwent P-wave signal averaging during electrophysiologic testing. The correlation between root mean square voltages for the initial 10 and 20 msec of the P-wave on the SAE and indices of electrophysiologic measurements, sinus node recovery time (SRT) and sinoatrial conduction time (SACT), obtained from programmed stimuli, was evaluated. It was found that the initial potentials of the P-wave on the SAE correlated negatively with SRT and SACT (-0.37 < or = r < or = -0.30). It was concluded that the initial potentials correlated with indices of electrophysiologic measurements, although the statistical significance was weak.

Adolescent↗
PubMed1997

Enhancement of estrogen receptor gene expression in the mediobasal hypothalamus during anestrus in the beagle bitch.

Estrogen receptor mRNA (ER mRNA) levels were measured in the mediobasal hypothalamus (MBH) of beagle bitches at different stages of the estrous cycle, and compared with levels in ovariectomized (OVX) estrogen-treated bitches. In cyclic bitches, the level of hypothalamic ER mRNA increased during the progression of anestrus and declined thereafter. Hypothalamic ER mRNA and plasma luteinizing hormone (LH) levels during anestrus and proestrus were positively correlated (r = 0.94, P < 0.001). In OVX bitches, levels of hypothalamic ER mRNA were low, and increased significantly after treatment with a low dose of estradiol benzoate. These results suggest that, during the course of anestrus in the bitch, hypothalamic ER mRNA expression increases, and may be up-regulated by estradiol.

Animals↗
PubMed1997

A hybrid baculovirus-T7 RNA polymerase system for recovery of an infectious virus from cDNA.

We established a hybrid baculovirus-T7 RNA polymerase system for transient expression in mammalian cells. Two recombinant baculoviruses carrying cDNA of bacteriophage T7 RNA polymerase, with or without a nuclear localization signal, under the control of a mammalian promoter were constructed. High level expression of T7 RNA polymerase was observed in various mammalian cell lines after infection with the recombinant baculoviruses. After transfection of plasmids containing the luciferase gene under the control of the T7 promoter, high luciferase activity was detected in cells infected with the recombinant baculoviruses. We also constructed a plasmid containing an entire cDNA clone of type 1 poliovirus under the T7 promoter. Two days after transfection of the plasmid into the cells infected with the recombinant baculoviruses, a high titer of poliovirus was recovered. The use of the recombinant baculoviruses did not cause any cytopathic effects even at a high multiplicity of infection. The lack of replication ability and low toxicity are the advantageous features of the hybrid baculovirus-T7 polymerase system in comparison with the widely used vaccinia-T7 polymerase system for gene expression and recovery of infectious viruses from its cDNA.

Animals↗
PubMed1997

Effects of octreotide, a somatostatin analogue, on gastric function evaluated by real-time ultrasonography.

BACKGROUND: Somatostatin exerts inhibitory effects on physiological functions in the gastrointestinal tract. The actions differ, however, depending on the test meal, dose, and other factors. AIMS: To determine by use of ultrasonography and scintigraphy the effect of a somatostatin analog, octreotide, on gastric emptying and antral contraction. SUBJECTS: Twenty healthy men; mean age 23.9 years METHODS: Subjects were studied for 7 days, once after subcutaneous injection of octreotide, 50 microg, 5 min before the ingestion of a test meal and once after subcutaneous injection of placebo. Ten subjects received a liquid meal, 10 others received a solid meal. With the liquid meal, gastric emptying was measured 15 min after its ingestion and antral contraction was measured for 15 min by ultrasonography. With the solid meal, gastric emptying was measured both by ultrasonography (n = 10) and by simultaneous scintigraphy (n = 6), with antral contraction measured by ultrasonography for 5 h after ingestion of the meal. RESULTS AND CONCLUSIONS: Octreotide given with a liquid or solid meal inhibited gastric emptying in healthy subjects. A significant suppression of antral contraction occurred only with a solid meal.

Adult↗
PubMed1997

Efficient gene transfer into various mammalian cells, including non-hepatic cells, by baculovirus vectors.

A baculovirus (Autographa californica nucleopolyhedrovirus) vector containing a strong promoter, the CAG promoter, was developed to introduce foreign genes into mammalian cells. Recombinant baculoviruses carrying a reporter gene under the control of the CAG promoter were inoculated into various mammalian cell lines. High-level expression was observed not only in hepatocytes but also in other non-hepatic cell lines tested. Expression of the reporter gene was detected even 14 days after infection. The infectious titre of the recovered baculoviruses decreased significantly after infection, indicating that the baculoviruses did not replicate in mammalian cells. We then compared the efficiencies of gene expression by the baculovirus vector with that of a replication-defective adenovirus vector by using the same expression unit. The same level of expression was observed in HepG2, HeLa and COS7 cells by both vectors. Efficient expression and proper processing were observed in mammalian cells infected with baculoviruses carrying genes coding for structural regions of hepatitis C virus. These results suggest that the baculovirus vector is a good tool for gene delivery into various mammalian cells in order to study the function of foreign genes.

Adenoviridae↗
PubMed1996

Increasing gonadotropin-releasing hormone release by perifused hypothalamus from early to late anestrus in the beagle bitch.

An in vitro perifusion system was used to investigate pulsatile gonadotropin-releasing hormone (GnRH) release from hypothalamic fragments derived from beagle bitches at different stages of the estrous cycle. The spontaneous GnRH release from the excised tissue fragments that include the "mediobasal hypothalamic-preoptic area-suprachiasmatic nucleus units' was episodic throughout all stages of the estrous cycle with a significantly high release rate during late anestrus and late proestrus. The GnRH release rate and plasma levels of luteinizing hormone were positively correlated (r = 0.94, P < 0.01). These results suggest that during the course of anestrus in the bitch the GnRH release rate increases while the pituitary responds accordingly.

Animals↗
PubMed1996

Effect of prior O2 breathing on ventilatory response to sustained isocapnic hypoxia in adult humans.

Sixteen healthy volunteers breathed 100% O2 or room air for 10 min in random order, then their ventilatory response to sustained normocapnic hypoxia (80% arterial O2 saturation, as measured with a pulse oximeter) was studied for 20 min. In addition, to detect agents possibly responsible for the respiratory changes, blood plasma of 10 of the 16 subjects was chemically analyzed. 1) Preliminary O2 breathing uniformly and substantially augmented hypoxic ventilatory responses. 2) However, the profile of ventilatory response in terms of relative magnitude, i.e., biphasic hypoxic ventilatory depression, remained nearly unchanged. 3) Augmented ventilatory increment by prior O2 breathing was significantly correlated with increment in the plasma glutamine level. We conclude that preliminary O2 administration enhances hypoxic ventilatory response without affecting the biphasic response pattern and speculate that the excitatory amino acid neurotransmitter glutamate, possibly derived from augmented glutamine, may, at least in part, play a role in this ventilatory enhancement.

Administration, Inhalation↗
PubMed1996

[A study of acute infection of herpes simplex virus in mouse trigeminal ganglia].

We investigated the shift to latency and protective reaction in mice trigeminal ganglia after inoculation of herpes simplex virus type 1 (HSV-1) onto the cornea. BALB/c mice were inoculated and the trigeminal ganglia were removed periodically. Lymphocytes in the ganglia were observed using immunocytochemical techniques. The results obtained were as follows: (1) HSV-1 positive neuronal cells were recognized at 3 days after inoculation but not at 14 days. (2) The relative proportion of T cells in lymphocytes was greater than that of B cells at 3 days, but B cells were more numerous at 5 days. Then T cells become more numerous again at 7 days. (3) Among the subsets in T cells, the ratio of CD4+ and CD8+ cells was almost equal at 3 days, but then CD4+ cells increased and CD8+ cells had disappeared at 14 days after inoculation. These results show that HSV-1 that reached the trigeminal ganglion from the cornea by axonal transport infected neuronal cells, multiplied there and then disappeared resulting in latency. Cellular immunity, especially the function of CD4+ cells, played a main role in this protective reaction by suppressing the viral growth.

Acute Disease↗
PubMed1995

When flour lipase inhibitor decreases serum lipid levels in male rats.

Triacylglycerol is digested and absorbed primarily through the action of lipase in the lingual and pancreatic juices. We used a wheat flour-derived lipase inhibitor to inhibit triacylglycerol absorption from the intestinal tract, and studied the effect on serum lipid concentration. Rats were given free access to high fat diets containing the lipase inhibitor at 0 (control), 0.05, 0.1 and 0.2% levels for 3 weeks and their serum triacylglycerol total cholesterol, and HDL-cholesterol concentrations were measured at weeks 1, 2, and 3. The measured values were significantly lower in the groups receiving the lipase inhibitor than in the control group. The degree of decrease in these respects was roughly dose-dependent. Additionally, the inhibitor intake raised the fecal lipid excretion and lowered the hepatic cholesterol level. It was, therefore, assumed that the inhibition of lipase in the digestive tract interfered with lipolysis and thereby with cholesterol absorption.

Animals↗
PubMed1995

[Evaluation of sinoatrial conduction by the initial potential of the P wave signal-averaged electrocardiogram].

We investigated whether sinoatrial conduction can be evaluated by the initial potential (IP) on the P wave signal-averaged electrocardiogram (PSAE). We studied 61 patients who underwent electrophysiologic study. Programmed stimulation was performed to obtain the sinoatrial conduction time (SACT) and the maximal sinus node recovery time (SRTmax). The root mean square voltages for the initial 10 and 20 msec of the filtered P waves (IP10 and IP20) were calculated based on PSAE. The association between IP10 and IP20 with SACT or SRTmax was analyzed by linear regression analysis. The reduction of IP10 or IP20 was negatively correlated with the prolongation of SACT, but was not correlated with the prolongation of SRTmax. Our findings showed that IP on the PSAE can be used to estimate the status of sinoatrial conduction.

Arrhythmias, Cardiac↗
PubMed1995

[The utility of body surface isochrone mapping of recovery time in diagnosing effort angina].

Myocardial ischemia is characterized by ST depression on a standard electrocardiogram caused by shortening of the action potential duration (APD). We investigated whether shortening of the APD can be used as a screening criterion, in place of ST depression, to diagnose effort angina. Estimation of APD was made based on recovery time (RT) on a 16-lead system signal-averaged electrocardiogram (SAE). RT was defined as the interval between the onset of the QRS complex and the maximum positive value during the T wave of SAE. The values of RT measured at each lead were plotted on a graph to produce an electrocardiographic isochrone map. RT were significantly shortened in all electrocardiographic leads in patients with effort angina. Shortening in RT was especially marked in the right precordal leads and was shown to be a highly specific criterion for screening effort angina.

Aged↗