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M Kudo

Publications and source records attributed to M Kudo.

At least 199 records · Page 11Linked to original sources
PubMed1996

[Reversal of portal-systemic encephalopathy by shunt-preserving disconnection of portal and systemic circulation].

Obliteration of portal-systemic shunts surgically or by interventional radiological techniques is fairly effective in reversing intractable portal-systemic encephalopathy (PSE), but is often associated with ascites accumulation and/or formation of esophageal varices. This study reports four patients with incapacitating PSE who were treated by interventional radiological techniques via percutaneous transhepatic route. One case had the shunt embolized directly. In the other three the blockage was placed on the proximal part of the splenic vein, whereby disconnecting the mesenteric-portal blood flow from the systemic circulation while preserving the shunt. The patient of shunt closure showed transient correction of encephalopathy, but developed massive ascites and esophageal varices, encephalopathy recurred, resulting in death from hepatic failure two months after the procedure. In the cases of shunt-preserving disconnection of portal and systemic circulation (SPDPS) immediate and permanent clearing of encephalopathy was achieved without manifestation of ascites or esophageal varices during the follow-up period of 10 to 31 months. The difference of portal pressure between before and after the procedure was 18 mmHg in the shunt-closed patient and 3 mmHg in SPDPS group. We conclude from this limited experience that SPDPS can be an effective and safe method in treating PSE in adequately selected patients.

Aged↗
PubMed1996

Protective effect of human ulinastatin against gentamicin-induced acute renal failure in rats.

We investigated the protective effect of human ulinastatin against gentamicin-induced acute renal failure in rats. Gentamicin sulfate was subcutaneously injected at a dose of 200 mg/kg for 5 consecutive days. After 3 days administration of gentamicin, a slight decrease in renal function was observed, as well as granulovascular degeneration in the proximal tubular cells as a change in the renal histology. After 5 days administration of gentamicin, a remarkable increase in plasma concentration of creatinine (from 0.27 +/- 0.02 to 1.17 +/- 0.18 mg/dL) and urea nitrogen (from 17.8 +/- 0.6 to 48.8 +/- 5.1 mg/dL) and a significant decrease in creatinine clearance (from 0.64 +/- 0.08 to 0.20 +/- 0.03 mL.100 g-1.min-1) were observed. In addition, an apparent increase in urinary excretion of N-acetyl-beta-D-glucosaminidase and albumin was detected. In the renal histology, proximal tubular necrosis and desquamation of the epithelial cells in the cortex were observed. Furthermore, hyaline cast formation was frequently observed in the outer stripe of the outer medulla. Ulinastatin at doses of 100,000 or 300,000 U/kg was coadministered intraperitoneally just after each gentamicin injection. Ulinastatin treatment showed a dose-dependent suppression of gentamicin-induced biochemical alterations and histological changes. After 5 days treatment with 300,000 U.kg-1.day-1 of ulinastatin, the magnitude of gentamicin-induced changes in renal function was significantly lessened, by 45-80%. The score for proximal tubular injuries and the rate of hyaline cast formation were also significantly lower in the same group of animals than those in the group treated with gentamicin alone. In the in vitro study, ulinastatin at 10-300 U/mL showed a concentration-dependent suppression on the fragility of the lysosomal membrane isolated from rat kidney cortex during hypotonic treatment. These results indicate that human ulinastatin has a prominent protective effect on gentamicin-induced acute renal failure in rats, and the lysosomal membrane stabilizing effect is possibly involved as a mechanism of this action.

Acute Kidney Injury↗
PubMed1995

Visualization of site-specific recombination catalyzed by a recombinase from Zygosaccharomyces rouxii in Arabidopsis thaliana.

Excision of a DNA segment can occur in Arabidopsis thaliana by reciprocal recombination between two specific recombination sites (RSs) when the recombinase gene (R) from Zygosaccharomyces rouxii is expressed in the plant. To monitor recombination events, we generated several lines of transgenic Arabidopsis plants that carried a cryptic beta-glucuronidase (GUS) reporter gene which was designed in such a way that expression of the reporter gene could be induced by R gene-mediated recombination. We also made several transgenic lines with an R gene linked to the 35S promoter of cauliflower mosaic virus. Each transgenic line carrying the cryptic reporter gene was crossed with each line carrying the R gene. Activity of GUS in F1 and F2 progeny was examined histochemically and recombination between two RSs was analyzed by Southern blotting and the polymerase chain reaction. In seedlings and plantlets of F1 progeny and most of the F2 progeny, a variety of patterns of activity of GUS, including sectorial chimerism in leaves, was observed. A small percentage of F2 individuals exhibited GUS activity in the entire plant. This pattern of expression was ascribed to germinal recombination in the F1 generation on the basis of an analysis of DNA structure by Southern blotting. These results indicate that R gene-mediated recombination can be induced in both somatic and germ cells of A. thaliana by cross-pollination of parental transgenic lines.

Arabidopsis↗
PubMed1995

Genetic heterogeneity of constitutively activating mutations of the human luteinizing hormone receptor in familial male-limited precocious puberty.

Genomic DNA from 32 unrelated families with male-limited precocious puberty was examined for the previously described Asp-578-->Gly, Met-571-->Ile, and Thr-577-->Ile mutations in transmembrane helix 6 of the human luteinizing hormone receptor (hLHR). Twenty-eight families had the inherited form of the disorder, and of these, 24 were found to have the Asp-578-->Gly mutation. Four additional mutations were found among the remaining four families with the inherited form and in four sporadic cases of the disorder: an A-->C transversion resulting in substitution of leucine for Ile-542 in the fifth transmembrane helix, an A-->G transition resulting in substitution of glycine for Asp-564 in the third cytoplasmic loop, a G-->T transversion resulting in substitution of tyrosine for Asp-578 in the sixth transmembrane helix, and a T-->C transition resulting in substitution of arginine for Cys-581 in the sixth transmembrane helix. Human embryonic kidney cells transfected with cDNAs for each of the mutant hLHRs, created by PCR-based mutagenesis of the wild-type hLHR cDNA, exhibited increased levels of basal cAMP production in the absence of agonist, indicating constitutive activation of the mutation hLHRs. Three of the additional mutations had specific features: Ile-542-->Leu and Cys-581-->Arg appeared ligand-unresponsive, whereas Asp-578-->Tyr appeared to correlate genotype with phenotype. We conclude that the region spanning nt 1624-1741 of exon 11 is a hotspot for heterogeneous point mutations that constitutively activate the hLHR and cause male-limited precocious puberty.

Amino Acid Sequence↗
PubMed1995

Stria terminalis conveys a facilitatory estrogen effect on female rat lordosis reflex.

The effects of bilateral cut of the stria terminalis (ST) on the dosage of estradiol benzoate (EB) needed to induce the lordosis reflex in the ovariectomized female rat were examined. Seven different doses ranging 0.5-20 micrograms were given s.c. in oil, daily for 2 days in a counterbalanced order, at 3-week intervals. The log dose-response relationship was linear in both ST-cut and sham-operated control rats. A significantly larger dose of 9.3 +/- 1.4 (mean +/- SEM) micrograms/day of EB was needed in the ST-cut rats (n = 8) to obtain a 50% lordosis quotient than in the controls (n = 7), in which a 2.0 +/- 0.3 micrograms/day dose had a similar effect. The slope of the dose-effect curve was significantly steeper in the ST-cut rats than in the controls. The ST mediates facilitatory effects of estrogen on the lordosis reflex that originate presumably in the amygdala.

Animals↗
PubMed1995

Electron microscopic study of synaptogenesis and myelination of the olfactory centers in developing rats.

Development of the central olfactory system was studied in the rat with an electron microscope at three main structures: the olfactory bulb, the lateral olfactory tract, and the primary olfactory cortex (the piriform cortex). As a parameter of development, the synaptic density was examined quantitatively in the bulbar glomerulus and layer Ia (termination of bulbofugal fibers) of the piriform cortex. which are the key stations of the olfactory pathway. The synaptic densities in the glomerulus and those in layer Ia were 5.7% and 4.6% on embryonic day 19, 15.8% and 12.5% on postnatal day (P) 0, and 57.3% and 37.2% on P10, as compared with the adult (100%). As another parameter of development, the density of myelinated axons in the lateral olfactory tract was examined quantitatively. The densities of myelinated axons in the tract were 0% on P5, 15.1% on P10, and 73.5% on P21 of the adult density. Maturation in the tract was still progressing, even at P21, in terms of bundle formation and the thickness of myelin sheaths. The results show that synaptogenesis in the bulbar glomerulus is followed by synaptogenesis in layer Ia of the piriform cortex, and that myelination in the lateral olfactory tract occurs over a prolonged period, even in the stages after P21.

Aging↗
PubMed1995

Acute and subacute inhalation toxicity of diborane in male ICR mice.

To clarify the toxicity of diborane, we conducted acute (15 ppm for 1, 2, 4 or 8 h) and subacute (5 ppm for 2 or 4 weeks) inhalation studies on ICR mice. The concentration resulting in a 50% kill after 4 h exposure was 31.5 ppm. Body weight gain was suppressed and the lung weight was increased in diborane-exposed mice in both acute and subacute studies. In the acute study, diffuse pan bronchiolitis-like lesions developed in the lung in various degrees depending on exposure time, which can be pathologically characterized as infiltration of inflammatory cells into the terminal bronchioles and surrounding alveoli, pulmonary congestion and bleeding and/or edema. In the subacute study, we observed lymphoid hyperplasia in the perivascular and peribronchial areas, and infiltration of macrophage and plasma cells into the alveoli. In the mice exposed for 4 weeks, the lesions were more severe than in those exposed for 2 weeks, consisting of hyperplasia and desquamation of Clara cells. In the nasal cavity, we saw mucous exudate and inflammatory cells, suggesting irritation caused by diborane. The histopathological findings, except for the respiratory organs, did not reveal any exposure-related changes. No significant changes were seen in hematological and serum biochemical examinations either. In conclusion, the target organ of diborane inhalation is the respiratory organs, particularly the lung. Further inhalation experiments are essential to investigate the safety exposure levels of diborane.

Administration, Inhalation↗
PubMed1995

Postnatal development of the projection from the medial superior olive to the inferior colliculus in the rat.

Normal projection development from the medial superior olive (MSO) to the inferior colliculus (IC) was examined by injecting Fluoro-Gold (FG), a retrograde tracer, into the IC unilaterally at postnatal days 0 (P0), P3, P7 and maturity. The rats were killed 1 day after FG injection. At all ages, labeled neurons in the MSO appeared on the ipsilateral side only, as in adult controls. The total number of MSO neurons counted in Nissl-stained sections was constant throughout the postnatal periods. The labeled frequency index of MSO neurons was increased stepwise (from 35% to 90%) with increasing postnatal stages (from P0 to adulthood), suggesting differential growth of early- and late-developing axons.

Age Factors↗
PubMed1995

Anatomical plasticity in the medial superior olive following ablation of the inferior colliculus in neonatal and adult rats.

We evaluated the consequences of unilateral ablation of the inferior colliculus (IC) upon the ascending projection from the medial superior olive (MSO) to the IC. Ablation of the IC was performed in rats aged between postnatal day 1 (P1) and maturity. All the rats were given injections of Fluoro-Gold (FG) into the ipsilateral IC at birth (P0) (before the ipsilateral IC was ablated in any case) so that growth of early-developing axons to the ipsilateral IC could be examined for any labeled neurons in the ipsilateral MSO. Upon reaching adulthood, the rats received injections of Fluoro-Ruby (FR) into the contralateral (intact) IC so that aberrant crossed projections to the intact IC could be examined for any labeled neurons in the ipsilateral MSO. These rats were killed 2 days after FR injections. The number of surviving cells in the ipsilateral MSO were counted in Nissl-stained sections for quantitative analysis of retrograde degeneration. The results show that: (1) the total number of neurons was reduced to 64-34% in the ipsilateral MSO as a result of IC ablation; (2) cell reduction by retrograde degeneration followed a U-shaped curve with a maximal effect in rats operated at P7 (reduced to 34%); (3) adult ablation of the IC led to retrograde degeneration that was less severe than that in late neonatal (P7) ablation; (4) an aberrant projection from the MSO to the contralateral IC occurred in rats operated at P1 and P3 but not in rats operated at P7 or maturity. Thus, our findings suggest that growth of late-developing axons is a major factor in the plasticity of this system of projection.

Age Factors↗
PubMed1995

A nonsense mutation of the human luteinizing hormone receptor gene in Leydig cell hypoplasia.

Leydig cell hypoplasia (LCH) is a form of male pseudohermaphroditism in which Leydig cell differentiation and testosterone production are impaired. This report describes the first case of a nonsense mutation (A1635C) in exon 11 of the human luteinizing hormone receptor (hLHR) gene in two sisters with LCH. This mutation causes loss of function of the receptor by introducing a stop codon at residue 545 in transmembrane helix 5 of the hLHR. Surface expression of the truncated hLHR (hLHR-t545) in human embryonic kidney cells stably transfected with cDNA encoding hLHR-t545 was diminished compared to the wild-type hLHR and hCG-induced cAMP accumulation was impaired. These results establish that single base mutations in exon 11 of the hLHR gene can produce inactivation as well as activation of the hLHR. Furthermore, they demonstrate that functional domains between transmembrane helix 5 and the C-terminal cytoplasmic tail of the hLHR are required for normal cell surface expression of the receptor and signal transduction.

Base Sequence↗
PubMed1995

Influence of different doses of methyl ethyl ketone on 2,5-hexanedione concentrations in the sciatic nerve, serum, and urine of rats.

Rats were injected subcutaneously with 2,5-hexanedione (2,5-HD 2.6 m mol/kg) alone (HD group) or with 2,5-HD and methyl ethyl ketone (MEK) (2.6 m mol/kg of each agent, HD&MEK group) or with 2,5-HD 2.6 m mol/kg and 5 times that dose (13.0 m mol/kg) of MEK (HD&5MEK group). The concentration of 2,5-HD in serum and in the sciatic nerve was determined 0.5, 1, 2, 4, 8, and 16 h after administration. Urinary 2,5-HD concentration was determined from the beginning of administration up to 16 h afterward. 1) The concentration of 2,5-HD in the serum, the sciatic nerve, and the urine was increased significantly (p < 0.05) in the co-administered groups; the higher the MEK doses were, the greater was the increase. 2) The clearance of 2,5-HD from both the serum and the sciatic nerve was delayed in the co-administered groups. The highest concentration in serum and the sciatic nerve appeared at 1 and 2 h respectively. After administration, the biological halflife (t1/2) of 2,5-HD from 1 to 8 h in serum was 6.5, 5.8 and 12.0 h for the HD, HD&MEK, and HD&5 MEK groups respectively. From 8 to 16 h, the t1/2 in serum was 1.2, 3.2 and 16.6 h for the HD, HD&MEK, and HD&5MEK groups, respectively. In nerve tissue, the prolongation of clearance in the co-administered groups was greater than that in serum, the t1/2 from 2 to 8 h being 5.2, 9.6 and 19.9 h for the HD, HD&MEK, and HD&5MEK groups, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1995

Spontaneous intraorbital hematoma mimicking orbital neoplasm--case report.

A 66-year-old female presented with spontaneous intraorbital hematoma manifesting as left exophthalmos after left eye discomfort persisting for 5 months. She had no history of head injury. Computed tomography revealed a round mass in her left orbit which was slightly high density with no postcontrast enhancement. A blood cyst was extirpated through frontotemporal craniotomy. Histological findings showed no tumor or vascular anomaly. Spontaneous intraorbital hematoma with insidious symptoms is extremely rare and should be considered in the differential diagnosis of orbital mass lesions.

Aged↗
PubMed1995

Differentiation of the olfactory epithelium during development.

Maturation of the olfactory epithelium was studied in the rat. As a developmental index of the olfactory epithelium, quantitation was based on the thickness and the number of cell layers of the epithelium. Mean epithelial thicknesses were 84 microns on embryonic day (E) 19, 94 microns on postnatal day (P) 0, 98 microns on P10 and 57 microns in adult. Average numbers of cell layers were 7 (E19), 8 (P0), 10 (P10) and 7 (adult). Thus the olfactory epithelium progressively increased in thickness between P0-P10, and later decreased in thickness as well as in number of cell layers toward adult. To clarify the number of mature receptor cells sending their axons to the olfactory bulb, the percentages of receptor cell labeling (number of labeled cells/total number of receptor cells) were estimated with an aid of retrograde fluorescent tracer injected into the olfactory bulb. As a result, their percentages were 34% (P1-P3), 50% (P8-P10) and 78% (adult). The ablation experiment of the bulb on P1 pups and adult rats revealed that the percentages of receptor cell degeneration were 31% in neonates (P1) and 76% in adults, confirming the results obtained from the retrograde tracing. Thus the present study shows the substantial increase of mature receptor cells during development and may provide a morphological basis in understanding of the functional maturity of olfaction.

Animals↗
PubMed1995

[Endocrine effects of nicardipine on intraoperative hypertension under droperidol-fentanyl-ketamine (DFK) anesthesia].

Effects of nicardipine on endocrine functions were evaluated in 10 surgical patients who received surgeries under total intravenous anesthesia with droperidol, fentanyl and ketamine (DFK). Plasma levels of norepinephrine (NE), epinephrine (E), plasma renin activity (PRA), aldosterone and atrial natriuretic peptide (hANP) were measured following nicardipine injection during 30 minutes of intraoperative hypertension. When the systemic blood pressure exceeded 160 mmHg systolic and 95 mmHg diastolic for five minutes, 0.5 mg approximately 10 mg of nicardipine was administered for 30 minutes to maintain the systolic blood pressure below 160 mmHg. Following the injection of nicardipine a significant reduction by 20% in the mean systolic and diastolic pressure was observed. Mean heart rate increased by 5%, but the increase was not significant. Plasma NE increased significantly 1.7 time from the control level at 15 minute following the injection. Plasma levels of E, PRA, aldosterone and hANP showed no significant changes.

Adult↗
PubMed1995

[Two cases of peripartum cardiomyopathy].

Two cases of peripartum cardiomyopathy, a rare type of dilated cardiomyopathy, are reported. A 36-year-old woman developed congestive heart failure 1 month after delivering her third child. Cardiac catheterization revealed diffuse hypokinesis of the left ventricle and an ejection fraction of 28%. The second study, 20 months later, demonstrated an ejection fraction of 46%. Endomyocardial biopsy showed mild interstitial edema. A 42-year-old woman developed toxemia during pregnancy. She delivered her second child at 38 weeks of gestation. Two weeks later, she developed congestive heart failure. Cardiac catheterization demonstrated diffuse hypokinesis of left ventricle with an ejection fraction of 40%. Endomyocardial biopsy revealed dense fibrosis. Follow-up angiography performed 8 months later showed similar findings with an ejection fraction of 34%. These two cases suggest the importance of evaluation of endomyocardial biopsy to determine the degree of interstitial fibrosis that may reflect the prognosis for patients with peripartum cardiomyopathy confirmed by measurements of ejection fraction.

Adult↗
PubMed1995

[Arterial plasma keton body levels during isoflurane anesthesia and surgery].

The authors measured arterial plasma levels of acetoacetate, 3-hydroxybutyrate, free fatty acid and the blood levels of lactate and glucose to evaluate fat metabolism during isoflurane anesthesia and surgery in twenty patients who ranged in age from 17 to 67 years. They underwent non-abdominal surgery (orthopedic surgery) or abdominal surgery (gastrointestinal or gynecological surgery). The operation started at 9 AM following starvation after 9 PM of the day before surgery. Anesthesia was induced with intravenous thiopental followed by intravenous succinylcholine to facilitate tracheal intubation, and maintained with isoflurane in 50 % nitrous oxide and 50 % oxygen. Vecuronium was given intravenously during surgery. Lactated Ringer's solution at a speed of 5-15 ml.kg-1.h-1 was also administered intravenously throughout the procedures. Patients who had received glucose solution or blood transfusion were excluded. Plasma acetoacetate and 3-hydroxybutyrate levels increased significantly with surgical stimulation in both groups and they were slightly higher in the abdominal group than those in the non-abdominal group. However there was no statistical difference in plasma keton body levels between the groups. Mild increases in plasma free fatty acid and blood lactate levels were detected during surgery in both groups to the same extent. Blood glucose increased significantly during surgery in both groups and the increase was statistically higher in the abdominal group than that in the non-abdominal group. The findings suggest that there is no difference in fat metabolism between non-abdominal and abdominal groups during surgical intervention lasting as long as 3 hours when patients are starved and do not receive any glucose during surgery.

Adolescent↗