Search PubMed⌕ Search

Biomedical subjects

T Hatanaka

Publications and source records attributed to T Hatanaka.

At least 91 records · Page 5Linked to original sources
PubMed1993

Odor responses of the vomeronasal system in Reeve's turtle, Geoclemys reevesii.

The number of vomeronasal receptor cells and olfactory receptor cells were determined in several turtles and tortoises. Using semi-aquatic turtles with developed vomeronasal organs, neural responses to various odor stimuli were recorded as extracellular unitary spike responses of vomeronasal receptor cells, compound action potentials from vomeronasal nerve twigs, induced wave responses on the accessory olfactory bulb (AOB) surface and unitary responses of AOB neurons. The vomeronasal system in turtles responded to various volatile and non-volatile chemicals. These results yield insights concerning functions of the vomeronasal organ in semi-aquatic turtles.

Animals↗
PubMed1993

Electrophysiologic studies in an infant with Möbius syndrome.

The electrophysiologic findings in an infant with congenital facial diplegia (Möbius syndrome) are presented. As to serial electrically elicited blink reflexes, the R1 amplitude was significantly reduced and the R2 latency was significantly prolonged. The M response of the orbicularis oculi muscle showed slightly reduced amplitude. Auditory brainstem responses exhibited a prolonged time between waves I and V and reduced amplitude of wave V on the right side. Somatosensory evoked potentials and visual evoked potentials were normal. These findings suggest some degree of impairment of the peripheral facial nerve, and brainstem dysfunction including the pons and lateral medulla.

Blinking↗
PubMed1993

Molecular cloning, sequencing and expression of core and NS3 fragments of HCV from patients with HCV infection.

Fragments of core and NS3 of hepatitis C virus-Hunan (HCV-Hun) were cloned by RT-PCR and gene recombinant techniques from blood samples collected in Hunan Province, China. In comparison with sequences of our samples with those of HCV-US and HCV-J, the homologies of nucleotides and amino acids were about 90%, indicating that fragments of core and NS3 of HCV-Hun were in a relative conserved region of HCV. Two fusion proteins containing the peptides coded by HCV core (MBP-HCV core) and HCV. NS3 (MBP-HCV. NS3-Gal) were expressed by Escherichia Coli with recombinant plasmids. The specific HCV antigenicity of the two fusion proteins were identified by western blotting. Therefore, MBP-HCV. core and MBP-HCV.NS3-Gal were found useful for anti-HCV assay.

Amino Acid Sequence↗
PubMed1993

[Treatment of advanced gastric and colorectal cancer with 5-FU, leucovorin and interferon-alpha].

Twenty-four patients with advanced or relapsed gastric or colorectal cancer were treated with a combination of 5-fluorouracil (5-FU), leucovorin (LV) and interferon-alpha (IFN-alpha). 5-FU was administered by rapid intravenous infusion at 350 mg/m2 for 5 consecutive days. Intravenous bolus administration of LV 20 mg/m2 was given before each 5-FU administration. This combination was repeated every 3 to 4 weeks. IFN-alpha (HLBI), 6MU, was administered subcutaneously daily. Of 13 patients with gastric cancer, there were 2 PR, 4 NC and 7 PD, and among 11 patients with colorectal cancer, there were 1 CR, 8 NC and 2 PD. All 16 previously treated patients had no clinical response. Responses were seen in patients with no prior chemotherapy and with good performance status. Most common toxicities observed were leucopenia, fever, stomatitis and diarrhea, which were all tolerable and reversible.

Adult↗
PubMed1993

[A case of severe milk allergy. Relationship with type I and Type III allergic reactions].

A case of cow's milk allergy related to type I and type III allergic reactions is reported. The patient is a one-month-old girl. She had watery diarrhea and abdominal distention soon after commencement of milk feeding two weeks after birth. She was cyanotic and floppy on admission. Intravenous complete hyperalimentation was tried to combat her diarrhea with good clinical effect. Then feeding with 605Z milk (enzyme digested cow's milk antigen, Meiji Milk Products Co., Ltd.) was started, and the diarrhea improved. Laboratory findings showed positive milk PK test, elevated IgE score, and positive milk specific RAST score, decreased serum complement, elevated levels of each immunoglobulin class of milk specific antibodies, especially milk specific IgG1 antibody and increased complement absorption test. She was diagnosed as having milk allergy related to both type I and type III allergies from the above-mentioned results. Specific antibodies were diminished after feeding with 605Z. Although her mother had not taken cow's milk over the past 10 years, she took a lot of milk during her pregnancy. But her serum milk specific antibodies were not elevated. It was suggested that the baby's antibodies were not derived from her mother but that the baby produced them by herself.

Animals↗
PubMed1992

Prediction of skin permeability of drugs: comparison of human and hairless rat skin.

Relationships between skin permeability and physicochemical properties of drugs were examined to establish a predictive method for the steady-state permeation rate of drugs through human skin. Human skin permeation properties fell into two categories: one in which the permeability coefficient is correlated to the partition coefficient, revealed with lipophilic drugs; and the other in which the permeability coefficients are almost constant, shown with hydrophilic drugs. The stratum corneum, the main barrier in skin, could be considered as a membrane with two parallel permeation pathways: lipid and pore pathways, and an equation for predicting the steady-state permeation rate of drugs was derived. The skin permeabilities of drugs for man were compared with those for hairless rat. The species difference in skin permeability found was suggested to be due to the difference in skin permeation pathways, since lipid content and water uptake of the stratum corneum varied between human and hairless rat skin.

Animals↗
PubMed1992

Programmed cell death in whole body and organ systems by low dose radiation.

New whole-body and organ systems were established to detect interphase cell death in the thymus, spleen and epithelial cells of intestinal crypts by low-dose radiation. Frozen sections of the thymus, spleen and intestine as thick as 8 microns were made after X-irradiation of whole body or removed organs, and then sections were stained with 0.02% erythrosin B solution. In unirradiated controls, a few numbers of erythrosin B positive cells (dead or dying cells) were observed in the thymus, spleen and intestinal crypt as a single cell death. When X rays were given to various strains of mice as a whole body dose, clusters of erythrosin B positive cells were produced. They appear at 2 hr after irradiation and reached maximum at 4 hr, remaining at a similar level until 8 hr after irradiation. The number of erythrosin B positive cells decreased after then by the elimination of dead cells, and they were observed like a single cell death at 24 hr after irradiation. When erythrosin B positive cells were scored 4 hr after irradiation, their total number and the number of cluster increased with increasing doses of X rays in the dose range from 0.05 to 0.5 Gy. It is noted that there were large differences in the radiation susceptibility among the inbred strains of mice for the induction of interphase cell death of thymic lymphocytes: e.g., high susceptibility in C57BL/6J and AKR/J, intermediate in N4, A/J, PT and ST, low in C3H/HeJ, HT, 101/H and DBA/2J, indicating that interphase cell death is genetically programmed. Similar results were observed with some chemical mutagens. Although a large increase of erythrosin B positive cells was observed in the thymus and spleen with methylprednisolone, there was no increase in the intestinal crypt, and vice versa with bleomycin, suggesting the organ specificity for the induction of interphase cell death by chemicals. For the in vitro method, the removed thymus was irradiated on the agar plate, and then incubated on the agar plate which was placed on the grid in the medium, so that the medium comes up to the organ through the agar plate. Frozen sections were made and stained with erythrosin B solution in the same way as the in vivo method. The number of erythrosin B positive cells in the organ culture system reached maximum at 5 hr after X-irradiation, e.g. slightly later than in the whole-body system. The efficiency was about 60% in C57BL/6J mice when compared with whole-body system.

Animals↗
PubMed1992

[Usefulness of transcutaneous gas monitoring during hemorrhagic shock].

This study was undertaken to confirm whether transcutaneous (tc) gas analysis during hemorrhagic shock could be used as an alternative to mixed venous gas analysis. Tc gases were measured and correlated with arterial and mixed venous gases in 10 anesthetized dogs during hemorrhagic shock and volume resuscitation. Throughout this experiment PtcO2 correlated well with PvO2 (r = 0.78, P less than 0.01), while PaO2 remained mostly constant, and PtcCO2 correlated well with PvCO2 (r = 0.82, P less than 0.01) rather than with PaCO2 (r = 0.63, P less than 0.01). A more detailed observation showed that during progressively decreased cardiac output, PtcO2 became lower than PvO2 and PtcCO2 became higher than PvCO2. We inferred from these observations that the changes of tc and mixed venous gases reflected those gases in tissues and that during severe shock maldistribution of peripheral blood flow prevented mixed venous gases from coming into equilibrium with tissue and tc gases. We conclude that the measurement of tc gases during shock is a more convenient and more reliable monitor of tissue gases than mixed venous analysis.

Animals↗
PubMed1992

Serial electrophysiological study on two infants with acute facial palsy.

Two infants with acute unilateral facial palsy were examined serially as to the electrically and mechanically elicited blink reflex, photo-evoked eyelid microvibration and auditory brainstem response (ABR). The results indicated that in hemifacial palsy beside the affection of the facial nerve also central pathways in the brainstem were involved in the pathogenetic processes. In particular, a neurapraxic change of the facial nerve itself in one case played an important role in pathogenesis, while a wide spread involvement was observed in another case. The clinical recovery of a patient with a wide spread involvement was more prolonged. We suggest that serial determinations of blink reflexes and ABR are helpful in clarifying the underlying pathogenetic processes concerning the brainstem affection during facial nerve palsy.

Blinking↗
PubMed1991

Effects of long-term medication for essential hypertension on cardiac hypertrophy and function.

The effects of long-term treatment of hypertensive patients with alacepril (angiotensin-converting enzyme inhibitor) on cardiac mass and function were investigated. A total of 12 patients was examined. Both systolic and diastolic blood pressure were significantly reduced by treatment with alacepril for 1 year. Left ventricular mass, as estimated by echocardiography, was significantly decreased by alacepril treatment, although electrocardiographic and chest x-ray findings were not significantly altered. Cardiac pump function, which was also assessed by echocardiography, was not changed. These results indicate that long-term treatment of hypertension with alacepril induces regression of cardiac hypertrophy without any change in cardiac contractile function.

Adult↗
PubMed1991

Prediction of the prognosis in neonatal asphyxia by photo-evoked eyelid microvibration.

Neonatal asphyxia causes hypoxic-ischemic encephalopathy and may damage the central nervous system. We studied neonatal asphyxia with photo-evoked eyelid microvibration (PEMV) which is a blink reflex elicited by photic stimuli. The latency of PEMV changed according to the severity of encephalopathy and the degree of unconsciousness. All of the neonate who had showed disappearance of PEMV died. When the prolonged latency persisted, the infant had a strong probability of sustaining neurological sequelae. PEMV provides useful information for predicting the outcome of neonatal asphyxia.

Asphyxia Neonatorum↗