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Biomedical subjects

Y Murata

Publications and source records attributed to Y Murata.

At least 37 records · Page 2Linked to original sources
PubMed2005

Effect of coffee intake on blood flow and maternal stress during the third trimester of pregnancy.

OBJECTIVE: To investigate the effects of maternal ingestion of an ordinary dose of coffee on maternal stress and placental and fetal blood circulation during the third trimester of pregnancy. METHODS: We performed a Doppler blood flow analysis for 10 women in the third trimester of pregnancy before and after they drank a cup of coffee. Salivary samples were collected from the 10 pregnant women and 14 nonpregnant controls just before coffee intake and 30 min later. Salivary cortisol levels and chromogranin A titers were determined. RESULTS: Coffee intake had no effect on maternal or fetal blood flow. Among the pregnant women, Salivary cortisol levels were significantly reduced after coffee intake but salivary chromogranin A concentration was not significantly different before and after coffee intake. CONCLUSION: The reduced salivary cortisol levels suggest that coffee intake decreases maternal stress during pregnancy.

Arteries↗
PubMed2005

Developmental changes in the expression of growth-associated protein-43 mRNA in the monkey thalamus: northern blot and in situ hybridization studies.

The expression of growth-associated protein-43 has been related to axonal elongation and synaptic sprouting. Using the Northern blot analysis, we investigated the developmental changes of growth-associated protein-43 mRNA in the thalamus of macaque monkeys. The amount of growth-associated protein-43 mRNA was high at embryonic day 125, and decreased at postnatal day 1. It increased again at postnatal day 8, reached its peak value at postnatal days 50-70, and then decreased gradually until postnatal year 1. We previously reported that the amount of growth-associated protein-43 mRNA in the cerebral cortex decreased roughly exponentially during perinatal and postnatal periods and that it approached the asymptote by postnatal day 70 [Oishi T, Higo N, Umino Y, Matsuda K, Hayashi M (1998) Development of GAP-43 mRNA in the macaque cerebral cortex. Dev Brain Res 109:87-97]. The present findings may indicate that extensive synaptic growth of thalamic neurons continues even after that of cortical neurons has finished. We then performed in situ hybridization to investigate whether the expression level of growth-associated protein-43 mRNA was different among various thalamic nuclei. In the infant thalamus (postnatal days 70-90), moderate to intense expression of growth-associated protein-43 mRNA was detected in all thalamic nuclei. Quantitative analysis in the infant thalamus indicated that the expression levels were different between the nuclear groups that are defined by the origin of their afferents. The expression in the first order nuclei, which receive their primary afferent fibers from ascending pathways [Guillery RW (1995) Anatomical evidence concerning the role of the thalamus in corticocortical communication: a brief review. J Anat 187 (Pt 3):583-592], was significantly higher than that in the higher order nuclei. While moderate expression was also detected in the adult dorsal thalamus, the expression in the first order nuclei was almost the same as that in the higher order nuclei. Thus, the in situ hybridization experiments indicated that the transient postnatal increase in the amount of growth-associated protein-43 mRNA, which was shown by the Northern blot analysis, was mainly attributed to enhanced expression in the first order nuclei during the postnatal period. This may be a molecular basis for environmentally induced modification of thalamocortical synapses.

Animals↗
PubMed2005

Helicobacter pylori infection and platelet counts during pregnancy.

OBJECTIVE: To investigate whether there is any correlation between Helicobacter pylori infection and platelet counts during pregnancy. METHODS: One hundred and twenty pregnant women without any complications were evaluated. Platelet counts were determined during pregnancy and postpartum. H. pylori infection was assessed by the detection of serum antibodies at the 3rd day postpartum. Statistically significant differences of platelet count between H. pylori-positive and -negative patients were determined. RESULTS: H. pylori infection was found in 29 of 120 (24.2%). Platelet counts in the 3rd trimester were 22.7+/-4.7 x 10(3)/microl in H. pylori-positive group and 22.8+/-5.6 x 10(3)/microl in negative group (p=0.98). Platelet count in the 3rd trimester in positive and negative patients were 93+/-17% and 94+/-20%, respectively, of that of the 1st trimester (p=0.92). The incidence of hyperemesis gravidarum in both groups was not significant (p=0.28). CONCLUSION: A correlation between H. pylori infection and thrombocytopenia during pregnancy was not found in this study.

Female↗
PubMed2005

Fractalkine in the peritoneal fluid of women with endometriosis.

OBJECTIVE: The objective of this study was to evaluate the presence of fractalkine in the ascites and the association between fractalkine levels in the ascites and endometriosis. METHODS: Peritoneal fluids and peripheral blood samples were obtained from patients undergoing laparoscopy for infertility work-up or laparoscopic cystectomy. Three samples of peritoneum were obtained from patients undergoing hysterectomy. Western blotting, RT-PCR and immunohistochemistry were performed. RESULTS: Fractalkine protein was detected in the ascites. Positive staining was confirmed in peritoneal surface cells and perivascular cells of the peritoneum. CX3CR1 positive cells were present in the cells in the peritoneal fluid. The fractalkine concentrations in the ascites of patients with endometriosis were lower than those without endometriosis. There was no significant difference between serum fractalkine levels in patients with and without endometriosis. CONCLUSION: The decreased level of fractalkine found in the peritoneal fluid of patients with endometriosis may contribute to the pathogenesis of endometriosis.

Adult↗
PubMed2005

Cholesterol feeding prevents adiposity in the obese female aromatase knockout (ArKO) mouse.

The aromatase (ArKO) knockout mouse develops obesity marked by increased gonadal fat depots. This obesity is characterized by pronounced hypertrophy and hyperplasia in adipocytes with corresponding increases in transcripts involved in fat development. Aromatase deficiency in mice and humans with natural mutations of the aromatase gene also leads to metabolic syndrome, particularly hepatic steatosis. In ArKO mice, this hepatic steatosis, the increased body weight and serum triglycerides are surprisingly prevented by cholesterol feeding. We sought to investigate whether the reduction in body weight upon cholesterol feeding is reflected in gonadal fat depots, which account for a large percentage of body weight in the ArKO mouse. Indeed, gonadal fat depots in female ArKO mice were significantly reduced after cholesterol feeding. Concomitantly, adipocyte hyperplasia and hypertrophy were dramatically reduced upon cholesterol feeding in ArKO mice. Real-time PCR analysis revealed concurrent changes with adipocyte volume in the levels of lipoprotein lipase, caveolin-1 and CD59 transcripts. Little change was observed in levels of transcripts involved in de novo fatty acid synthesis, beta-oxidation, lipolysis, differentiation and cholesterol metabolism, suggesting that cholesterol feeding prevents hyperplasia and hypertrophy of ArKO adipocytes, possibly as a consequence of changes in transcript levels of lipoprotein lipase and therefore fatty acid uptake.

Adipocytes↗
PubMed2005

Changes in expression of the genes for the leptin receptor and the growth hormone-releasing peptide/ghrelin receptor in the hypothalamic arcuate nucleus with long-term manipulation of adiposity by dietary means.

Changes in leptin and ghrelin levels occur with alterations in adiposity, but signalling may be affected by levels of the relevant receptors. We measured expression of the leptin receptor (Ob-Rb) and the ghrelin/growth hormone releasing peptide receptor (GHS-R) in the arcuate nucleus of sheep held at either high or low levels of adiposity. Plasma growth hormone (GH) levels were lower in Fat animals and higher in Lean animals. Plasma insulin and leptin levels were higher in Fat animals and lower in Lean animals. Frozen hypothalamic sections of arcuate nucleus were extracted and mRNA levels measured for mRNA for Ob-Rb and GHS-R. Gene expression for both Ob-Rb and GHS-R was higher in Lean animals than in Fat animals, with no difference in expression between Fat and Normal animals. A second group of animals (n = 4 per group) was used for double-labelling immunohistochemistry to determine whether the increase in Ob-Rb gene expression was translated into Ob-Rb protein and to ascertain whether this effect is localised to the cells of the arcuate nucleus that produce either neuropeptide Y (NPY) and/or pro-opiomelanocortin-derived peptides. Lean animals displayed a 255% increase in immunoreactive NPY cells (P < 0.005), a 167% increase in cells with Ob-Rb (P < 0.037) protein and a 344% increase in cells that were staining for both NPY and Ob-Rb (P < 0.02). There was no difference between the Normal and Lean animals in the number of cells that were detected with an adrenocorticotrophic hormone (ACTH) antibody or the number of ACTH-immunoreactive cells that also stained for Ob-Rb. Finally, we measured plasma ghrelin levels in Normal, Fat and Lean ewes (n = 4/group); levels were higher (P < 0.05) in Fat animals than in Lean animals. We conclude that lowering body weight leads to increased expression of Ob-Rb, ghrelin/GHS-R expression and proportion of NPY cells that express Ob-Rb in the arcuate nucleus. This may be an adaptive mechanism to increase responsivity to both leptin and ghrelin.

Adipose Tissue↗
PubMed2004

Therapeutic efficacy of sustained drug release from chitosan gel on local inflammation.

The model anti-inflammatory drug prednisolone (PS) was retained in chitosan (CS) gel beads, which were prepared in a 10% aqueous amino acid solution (pH 9.0). Sustained release of PS from the CS gel beads was observed. Carrageenan solution was injected into air pouches (AP), which were prepared subcutaneously on the dorsal surface of mice, in order to induce local inflammation. CS gel beads retaining PS were then implanted into the AP to investigate the therapeutic efficacy of sustained PS release against local inflammation. In vivo PS release from CS gel beads was governed by both diffusion of the drug and degradation of the gel matrix. Sustained drug release by CS gel beads allowed the supply of the minimum effective dose and facilitated prolonged periods of local drug presence. Inflammation indexes were significantly reduced after implantation of CS gel beads when compared with injection of PS suspension. Thus, extension of the duration of drug activity by CS gel beads resulted in improved therapeutic efficacy. These observations indicate that CS gel beads are a promising biocompatible and biodegradable vehicle for treatment of local inflammation.

Adjuvants, Pharmaceutic↗
PubMed2004

Northern blot and in situ hybridization analyses for the development of myristoylated alanine-rich c-kinase substrate mRNA in the monkey cerebral cortex.

Myristoylated alanine-rich C-kinase substrate (MARCKS) is a major neuron-specific substrate for protein kinase C, and is involved in both neurite outgrowth and synaptic plasticity. Using both Northern blot and in situ hybridization techniques, we investigated whether the expression of MARCKS mRNA in the monkey cerebral neocortex and hippocampus changed during the developmental period. In each of four neocortical areas examined, i.e. the prefrontal area (area FD of [Illinois Monographs in the Medical Sciences (1947) 1]), the temporal association area (TE), the primary somatosensory area (PB), and the primary visual area (OC), the Northern blot analysis showed that the amount of MARCKS mRNA was high during the fetal and early postnatal periods, and decreased sharply between postnatal day 70 and postnatal month 6. The in situ hybridization experiments showed that the expression of MARCKS mRNA was decreased in every layer of neocortical areas at postnatal month 6 or later. In the primary sensory areas (areas PB and OC), the degree of decrease was higher in the supragranular layers (layers II and III) than in the infragranular layers (layers V and VI). In the hippocampus, the developmental change in the amount of MARCKS mRNA was small, but the in situ hybridization revealed a prominent decrease in Ammon's horn in monkeys on postnatal month 8 and later. These findings indicate that region-specific expression of MARCKS mRNA is established around postnatal month 6. We suggest that the extensive expression of MARCKS mRNA is one of the molecular bases of high plasticity in the infant cerebral cortex.

Animals↗
PubMed2003

Multimodality treatments with endoscopic mucosal resection of esophageal squamous cell carcinoma with submucosal invasion.

BACKGROUND AND STUDY AIMS: A standard treatment for esophageal squamous cell carcinoma (SCC) with submucosal invasion is considered to be radical resection at present. In this study, we evaluated the efficacy of multimodality treatments with endoscopic mucosal resection (EMR) of esophageal SCC with submucosal invasion. METHOD: Eighteen cases of SCC with submucosal invasion were treated with EMR. Lymphatic invasion was found in 11 cases (67%), and there were no cases of blood vessel invasion. EMR was performed prior to any other treatment. Chemotherapy and/or radiotherapy were added if indicated by the histopathological features. RESULTS: There were no cases of local recurrence. Lymph-node recurrence was detected in 1 case treated with EMR alone. There were no cases of cancer death. The overall survival rate was 83% in all patients. CONCLUSIONS: Multimodality treatments with EMR were effective in treating esophageal SCC with submucosal invasion.

Adult↗
PubMed2003

Acetazolamide vasoreactivity evaluated by transcranial harmonic perfusion imaging: relationship with transcranial Doppler sonography and dynamic CT.

UNLABELLED: To establish the reliability and clinical significance of transcranial ultrasonic harmonic perfusion imaging (HPI), we evaluated HPI's relationships with transcranial Doppler (TCD) and with dynamic CT (DCT), during acetazolamide (ACZ) vasoreactivity tests. METHODS: The subjects were 12 neurological patients. Time-averaged maximum velocity (TAVMX) in the middle (MCA) and posterior cerebral arteries was measured by TCD. Time-intensity (-density) curves of HPI (DCT) after bolus intravenous contrast injections were created in 3 regions of interest (ROI) on the axial plane involving the temporal lobe, basal ganglia, and thalamus on both sides. Assessments of vasoreactivity were based on comparisons conducted before and after ACZ administration in terms of: a) relative changes (%delta) of the TCD TAVMX, b) HPI contrast area enlargement, c) %delta of calculated cerebral blood volume and flow of the HPI and DCT. RESULTS: 1) TCD vasoreactivity decrease in the left MCA tended to correlate with lower frequency of HPI contrast area enlargement on the left side. 2) HPI and DCT vasoreactivity tended to be disturbed in the same side ROIs. CONCLUSIONS: Transcranial HPI achieves repeatable non-invasive bedside evaluation of cerebrovascular reserve capacity through qualitative and quantitative measurements of brain tissue perfusion, and will have clinical value in pathophysiological follow-up and therapeutic effectiveness determination of neurointensive care patients.

Acetazolamide↗
PubMed2003

BOLD functional MRI may overlook activation areas in the damaged brain.

Clinical applications of blood-oxygenation-level-dependent contrast functional MRI (BOLD-fMRI) have been rapidly moving toward routine non-invasive cortical mapping in the patients with brain disorders. However, it is not yet clear whether the damaged brain shows same cerebral blood oxygenation (CBO) changes during neuronal activation as those in the normal adult. We compared the activation mapping obtained by BOLD-fMRI and the evoked-CBO changes measured by near infrared spectroscopy (NIRS) in normal adults (6 cases) and patients with damaged brain (6 cases of cerebral ischemia and 10 cases of brain tumors in or adjacent to the motor cortex). BOLD-fMRI demonstrated robust activation areas in the primary sensorimotor cortex (PSMC) during contralateral hand grasping tasks in all of the normal adults; however, in the cerebral ischemia (6 cases) and the brain tumors (2 cases), BOLD-fMRI demonstrated only limited activation areas in the PSMC on the lesion side during the task. NIRS demonstrated an increase of focal concentration of oxyhemoglobin and total hemoglobin at the PSMC during the task in all of the normal adults and the patients, indicating the presence of rCBF increase in response to neuronal activation. A focal concentration of deoxyhemoglobin decreased during the task in the normal adults, however, in the patients that showed limited activation areas by BOLD-fMRI, deoxyhemoglobin concentrations increased during the entire course of the task. In summary, the evoked-CBO changes occurring in the damaged brain differed from those in the normal brain. This indicates that BOLD-fMRI may overlook activation areas in the damaged brain.

Brain Ischemia↗
PubMed2003

A single administration of interleukin-4 antagonistic mutant DNA inhibits allergic airway inflammation in a mouse model of asthma.

Interleukin 4 (IL-4) is essential for the switching of B cells to IgE antibody production and for the maturation of T helper (Th) cells toward the Th2 phenotype. These mechanisms are thought to play a crucial role in the pathogenesis of the allergic airway inflammation observed in asthma. In the present study, we examined the anti-inflammatory effects of DNA administration of murine IL-4 mutant Q116D/Y119D (IL-4 double mutant, IL-4DM), which binds to the IL-4 receptor alpha and is an antagonist for IL-4. Immunization of BALB/c mice with alum-adsorbed ovalbumin (OVA) followed by aspiration with aerosolized OVA resulted in the development of allergic airway inflammation. A single administration of IL-4DM DNA before the aerosolized OVA challenge protected the mice from the subsequent induction of allergic airway inflammation. Serum IgE level and extent of eosinophil infiltration in bronchoalveolar lavage (BAL) from IL-4DM DNA-administered mice were significantly lower than those in BAL from control plasmid-immunized mice. In our study, IL-4 or IL-4 mutants were not detected in sera from mice that had received a single administration of IL-4DM DNA. The results of this study provide evidence for the potential utility of IL-4 mutant antagonist DNA inoculation as an approach to gene therapy for asthma.

Animals↗