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H Sameshima

Publications and source records attributed to H Sameshima.

54 records · Page 3Linked to original sources
PubMed1987

[Clinical and myopathological findings in polymyositis].

The present report analyzed a clinical and myopathological findings of 60 patients defined for the diagnosis of polymyositis. Patients were classified in four groups according to the system Walton and Adams. Forty five per cent were classified as Group I, 28.3 per cent as Group II, 15.0 per cent as Group III and 11.7 per cent as Group IV. Seven patients were associated with a malignant neoplasm and all of them were over fifty. The primary growth was carcinoma of the lung in 2, of the prostate, ovarium, stomach in one case each, and in one case a chronic myelogenous leukemia and in one case a malignant lymphoma. The female to male ratio was 2:1. Though cases were seen in all age groups, the largest number was in the sixth decade. The presenting symptoms and signs were essentially similar to those reported before. Proximal lower and upper limb weakness was the most frequent symptoms (91.7 and 83.3 per cent respectively). Other characteristic symptoms were skin changes, muscle pain, arthralgia and Raynaud's phenomenon. The CK was measured at the time of presentation in 58 of the 60 cases. Normal values were found in 18.3 per cent of cases. In general, muscle biopsy was performed in the first stage of the disease. A diagnostically abnormal biopsy was 55 cases (92 per cent), but 8 per cent of cases had normal biopsy. The characteristic changes in the biopsies from 60 cases were muscle fiber necrosis, inflammatory infiltration, fibrosis, basophilia and increase of internal nuclei. We could not get a significant difference between the two groups. However all of the cases of Group IV had muscle fiber necrosis, inflammatory infiltration and fibrosis.

Adolescent↗
PubMed1986

Fetal breathing movement, sleep state and cardiovascular responses to an inhibitor of mitochondrial ATPase in sheep.

Hypoxia abolishes breathing movements in fetal sheep, perhaps by reducing ATP synthesis within regulatory brain cells. This possibility was examined by administering to 13 chronically catheterized fetal sheep oligomycin B, a mitochondrial ATPase inhibitor. Injections into the left external carotid artery of oligomycin B (170 +/- 19 micrograms/kg in 9 fetuses) reduced significantly (P less than 0.01) the incidence of fetal breathing movements from a control mean of 52 +/- 6.3% to 6 +/- 2.2 and 9 +/- 4.4% during the first and second hours after drug injection. Oligomycin did not decrease significantly the incidence of low voltage electrocortical activity or reduce the average duration of a cycle of low and high voltage electrocortical states. Nor did it decrease significantly the incidence of rapid eye movements. Fetal heart rate and mean arterial pressure were not significantly affected, and the arterial blood gases and pH did not significantly differ from control values. However, a large dose of the drug (700 micrograms/kg) produced an isoelectric electrocorticogram, hypertension, and bradycardia associated with a rise in arterial PO2 and a severe metabolic acidosis. In 3 fetal sheep oligomycin also inhibited continuous breathing induced by indomethacin. Injection of the vehicle (ethanol) alone did not alter the incidence of breathing movements, electrocortical activity, eye movements or blood gases. These results suggest that reduced mitochondrial production of ATP may be a mechanism by which hypoxia abolishes fetal breathing activity.

Adenosine Triphosphatases↗
PubMed1986

Effects of moderate hypoxia on fetal electrocortical activity, eye movements, and breathing activity in sheep.

Isocapnic hypoxaemia (delta PaO2 = -8.0 +/- 0.5 mmHg; delta CaO2 = -2.86 +/- 0.20 ml/dl) was produced in fetal sheep by having the ewe breathe for one hour a gas mixture (v/v) of 10.5% O2 and 1.5% CO2 in N2. Mean fetal heart rate, blood pressure, and incidence of low voltage electrocortical activity were not affected. However, the incidence of rapid-eye-movements and breathing activity was reduced by about 40%. Breathing movements during hypoxaemia had a mean inspiratory time, breath interval, and tracheal pressure amplitude which did not differ significantly from those during control experiments in which the ewe breathed air from the plastic bag. These observations suggest that hypoxia decreases the incidence of breathing movements but does not affect the amplitude or pattern of breathing activity and that it may reduce the incidence of eye movements and breathing activity through a common mechanism.

Animals↗
PubMed1982

Superovulation induced by a single pituitary gland transplanted beneath the kidney capsule in adult rats.

Different numbers of rat pituitary glands, taken from male and female rats before and after puberty, were transplanted into various sites in female rats at different stages of the oestrous cycle. Ovulation was checked by counting ova in oviducts on the next expected day of ovulation. Ovulation was induced by transplantation beneath the kidney capsule in early dioestrus of half, one or three glands from 35- to 41-day-old male rats (18.6+/-3.1 (S.E.M.), 32.6+/-2.8 and 49.8+/-4.8 ova shed respectively). The transplantation of glands from mature female rats did not induce supraovulation but inhibited the expected ovulation. The most effective stage for inducing superovulation was early dioestrus and, to a lesser extent, most effective stage for inducing superovulation was early dioestrus and, to a lesser extent, oestrus; transplantation during late dioestrus was ineffective. The effective sites of transplantation were beneath the kidney capsule and intramuscularly but not subcutaneously. Representative pituitary glands from 35- to 41-day-old male rats and adult female rats were assayed for LH and FSH content to interpret the mechanisms of superovulation . The pituitary glands from the male rats contained larger amounts of LH and especially of FSH than those found in the female rats. The experiments indicated that superovulation can be induced successfully by the transplantation of a single pituitary gland from male and immature female rats without any additional treatment with human chorionic gonadotrophin; the failure of the female pituitary transplants to induce superovulation may be due to the insufficient content of LH and FSH.

Animals↗
PubMedDate not supplied

Causes of maternal mortality in Japan.

CONTEXT: Japan's maternal mortality rate is higher than that of other developed countries. OBJECTIVES: To identify causes of maternal mortality in Japan, examine attributes of treating facilities associated with maternal mortality, and assess the preventability of such deaths. DESIGN AND SETTING: Cross-sectional study of maternal deaths occurring in Japan between January 1, 1991, and December 31, 1992. SUBJECTS: Of 230 women who died while pregnant or within 42 days of being pregnant, 197 died in a hospital and had medical records available, 22 died outside of a medical facility, and 11 did not have records available. MAIN OUTCOME MEASURES: Maternal mortality rates per 100,000 live births by cause (identified by death certificate review and information from treating physicians or coroners); resources and staffing patterns of facilities where deaths occurred; and preventability of death, as determined by a 42-member panel of medical specialists. RESULTS: Overall maternal mortality was 9.5 per 100,000 births. Hemorrhage was the most common cause of death, occurring in 86 (39%) of 219 women. Seventy-two (37%) of 197 deaths occurring in facilities were deemed preventable and another 32 (16%) possibly preventable. Among deaths that occurred in a medical facility with an obstetrician on duty, the highest rate of preventable deaths (4.09/100,000 live births) occurred in facilities with 1 obstetrician. Among the 72 preventable deaths, 49 were attributed to 1 physician functioning as the obstetrician and anesthetist. While the unpreventable maternal death rate was highest in referral facilities, the preventable maternal death rate was 14 times lower in referral facilities than in transferring facilities. CONCLUSIONS: Inadequate obstetric services are associated with maternal mortality in Japan. Reducing single-obstetrician only delivery patterns and establishing regional 24-hour inpatient obstetrics facilities for high-risk cases may reduce maternal mortality in Japan. JAMA. 2000;283:2661-2667.

Adolescent↗
PubMedDate not supplied

Vasopressin and catecholamine responses to 24-hour, steady-state hypoxemia in fetal goats.

The purpose of the present study was to determine the effect of prolonged hypoxemia without acidemia on fetal stress hormones. Twenty-four-hour hypoxemia was conducted in nine chronically catheterized pregnant goats to determine fetal plasma concentrations of arginine vasopressin (AVP), epinephrine (E), and norepinephrine (NE). Nine experiments were performed. Six resulted in nonacidemic, steady-state hypoxemia, and three incidentally resulted in hypoxemia with progressive acidemia. In steady-state hypoxemia, fetal PO2 decreased significantly from 28.1 +/- 2.4 Torr to 18.8 +/- 2.5 Torr, fetal PCO2 also decreased significantly by about 5 Torr, and pH values did not change significantly. Fetal plasma concentrations of AVP, E, and NE were significantly increased at 1 h of hypoxemia. As hypoxemia continued, AVP returned to control level by 24 h, while E and NE remained elevated throughout the hypoxemic period. In the three experiments with progressive acidemia, AVP, E, and NE increased further as fetal acidosis progressed. We conclude that fetal AVP acts as a shorter-term stress hormone than E and NE in steady-state hypoxemia. This adaptive response is present without progressive acidosis. We also conclude that accompanying acidemia is a more potent stimulus for AVP, E, and NE than isolated hypoxemia during longer-term studies.

Acidosis↗
PubMedDate not supplied

Neonatal 24-hour urinary C-peptide and birth weight in infants of diabetic mothers.

OBJECTIVE: Our purpose was to investigate the relationship between the birth weights and 24-h urinary C-peptide in infants of diabetic mothers. METHODS: Sixty pregnancies with gestational diabetes mellitus (DM) were enrolled. Neonatal urine was collected for the first and second 24 h for measuring C-peptide. Birth weights were classified into 3 categories according to the Japanese standard curves; heavy-for-date (HFD), appropriate-for-date (AFD), and light-for-date (LFD). Unpaired t-test was used for comparison of 24-h urinary C-peptide in the 3 birth weight categories, with P-value <0.05. There were 7 HFD, 47 AFD, and 6 LFD infants. Birth weight averaged 3.9+/-0.7, 3.0+/-0.4, and 2.3+/-0.3 kg, respectively. RESULTS: Insulin concentrations of the umbilical artery were significantly higher in HFD than in AFD, and significantly higher in AFD than in LFD (49.5+/-45.1, 16.8+/-15.2, and 6.3+/-6.1 microU/ml). During the first 24 h, urinary C-peptide was significantly higher in HFD than in AFD (2.73+/-1.52 vs. 0.76+/-0.81 microg/day), and significantly higher in AFD than in LFD (0.27+/-0.27). On the second day, there was no longer statistical significance. CONCLUSIONS: Measurement of 24-h urinary C-peptide revealed that, among infants of diabetic mothers, HFD infants continue to secrete more insulin than AFD and LFD infants for the first 24 h.

Birth Weight↗
PubMedDate not supplied

Effects of magnesium sulfate on the fetal heart rate response during acute hypoxemia in goats.

OBJECTIVE: The effects of magnesium sulfate on fetal heart rate (FHR) response during acute hypoxemia in goats were investigated. METHODS: The FHR responses due to hypoxemia during magnesium sulfate infusion (Mg study) were compared with those during vehicle infusion (controls) in six chronically instrumented goat fetuses at 125-130 days' gestation. RESULTS: Four-hour infusions of magnesium sulfate significantly increased fetal plasma concentrations of magnesium from 2.3 to 6.5 mg/dL. During the hypoxemic period, the fetal arterial oxygen pressure was significantly decreased from 29.0 +/- 2.5 to 14.6 +/- 2.6 torr in the controls, and from 28.9 +/- 3.9 to 13.7 +/- 4.7 torr during the Mg study. Neither arterial carbon dioxide pressure nor pH was significantly altered. In the controls, FHR was significantly decreased by hypoxemia, accompanied by increases in variability. In the Mg study, FHR was not significantly decreased by hypoxemia. Acute hypoxemia also increased the FHR variability during magnesium infusion, which was significantly reduced compared with those in the control population. CONCLUSION: Magnesium sulfate masks FHR-slowing responses during acute hypoxemia in fetal goats.

Animals↗
PubMedDate not supplied

Periodic fetal heart rate decelerations during 6 hours' hypoxemia induced in goats.

OBJECTIVE: To determine if fetal heart rate (FHR) decelerations periodically occur with uterine contractures during 6 hours' induced hypoxemia in goats. METHODS: In five chronically catheterized goat fetuses at 125-130 days' gestation, incidence of FHR decelerations was compared between 6 hours' control time and 6 hours' induced hypoxemia with two-way ANOVA and Duncan's multiple range test. Three other fetuses were used as controls for circadian rhythm. RESULTS: Fetal PaO2 was significantly decreased from 26.1 to 16.3 mmHg without acidemia. During hypoxemia, 42 decelerations were induced along with 5 initial decelerations during the acute phase hypoxemia. Incidence of decelerations increased significantly from 0.07 +/- 0.15 per hour in 6-hour controls to 1.40 +/- 0.28 per hour during 6 hours' induced hypoxemia. Short-term variability and long-term variability of the 42 decelerations were significantly increased. These variabilities were also increased during the 5 initial decelerations. Frequency of uterine contractures did not change during hypoxemia. There was an observable association of FHR decelerations with uterine contractures during hypoxemia. CONCLUSION: Fetal heart rate decelerations occurred periodically in association with uterine contractures during induced 6 hours' hypoxemia, which were characterized by slow onset and recovery with increases in variability.

Animals↗
PubMedDate not supplied

Fetal glioblastoma: rapid growth during the third trimester.

We present a case of fetal glioblastoma which appeared after 28 weeks' gestation. The first ultrasonographic finding was an enlarged fetal head with right shifted falx cerebri at 31 weeks' gestation. At 33 weeks, a large and high echogenic mass in the left hemisphere and right enlarged ventricle was identified. Magnetic resonance imaging showed that the tumor was localized in the left hemisphere and a margin of the tumor was defined. Because fetal well-being judging from biophysical parameters was good and we considered that the tumor was resectable, a male fetus weighing 2,670 g was delivered at 34 weeks' gestation by cesarean section. However, he was inoperable due to consumptive coagulopathy and rapid growth of the tumor, and died on the 41st day of life.

Adult↗
PubMedDate not supplied

Antenatal diagnosis of tetralogy of Fallot with absent pulmonary valve accompanied by hydrops fetalis and polyhydramnios.

The case presented is an antenatal diagnosis of tetralogy of Fallot with absent pulmonary valve which was accompanied by hydrops fetalis and polyhydramnios with an absent stomach echo. Absent pulmonary valve was diagnosed by a cystic, pulsatile, aneurysmal dilatation of pulmonary arteries and a relatively small pulmonary valve annulus without a definite valve echo, in which a typical to-and-fro flow pattern was detected by the Doppler flow analysis. We will discuss some plausible roles of the grossly enlarged pulmonary arteries on hydrops fetalis and polyhydramnios.

Adult↗
PubMedDate not supplied

The protective effects of long-acting recombinant human pancreatic secretory trypsin inhibitor (R44S-PSTI) in a rat model of cerulein-induced pancreatitis.

The effects of pancreatic secretory trypsin inhibitor (PSTI) on cerulein-induced pancreatitis were studied in a rat model. Arg44 of PSTI was replaced by Ser using site-directed mutagenesis (R44S-PSTI). R44S-PSTI has a longer half-life than the natural form. Pancreatitis was induced by four intramuscular injections of cerulein (50 microgram/kg at 1 h intervals). Continuous intravenous infusion of R44S-PSTI began at a dose of 20 micrograms/kg/h 30 min before the first cerulein injection, and was completed 3 h after the last cerulein injection. Tumour necrosis factor (TNF-alpha) production by isolated peritoneal macrophages from rats with cerulein-induced pancreatitis increased following lipopolysaccharide stimulation, compared to control rats (P < 0.01). R44S-PSTI administration significantly decreased the TNF-alpha production by peritoneal macrophages from rats with cerulein-induced pancreatitis (P < 0.05). In addition, R44S-PSTI significantly reduced serum amylase activity (P < 0.01) and pancreatic wet weight after pancreatitis induction (P < 0.05). Histological examination revealed marked acinar cell vacuolization, interstitial oedema, and cellular infiltration in cerulein-induced pancreatitis, but a lesser degree of histological change in rats that were treated with R44S-PSTI. Prophylactic use of intravenous R44S-PSTI infusion may reduce the severity of acute pancreatitis either histologically or serologically.

Amylases↗
PubMedDate not supplied

Magnesium sulfate and fetal plasma concentrations of epinephrine, norepinephrine, and vasopressin in response to acute hypoxemia in goats.

OBJECTIVE: We measured fetal plasma concentrations of epinephrine, norepinephrine, and vasopressin during acute hypoxemia in goats and tested whether hypermagnesemia altered these endocrine responses. METHODS: Five chronically catheterized goat fetuses at 124-129 days' gestation were used. After 4 hours of infusion (magnesium or vehicle as controls), 30 minutes of hypoxemia was induced by infusing nitrogen gas through a maternal tracheal catheter. Fetal plasma concentrations of epinephrine, norepinephrine, and vasopressin were measured before and during hypoxemia. Both magnesium sulfate and vehicle infusions were performed in each animal. Repeated-measures analysis of variance (ANOVA) and two-way ANOVA with post hoc test were used to determine statistical significance. RESULTS: During hypoxemia, fetal PO(2) decreased significantly from 30 to 14 mmHg with no significant changes in fetal pH or PCO(2) in both groups. Fetal heart rate was reduced significantly by hypoxemia, but to a lesser extent in the magnesium group (change in decrease in fetal heart rate: 41 beats per minute [bpm] in controls versus 26 bpm with magnesium). Mean blood pressure did not change significantly during hypoxemia in both groups. Fetal plasma concentrations of epinephrine, norepinephrine, and vasopressin significantly increased from the prehypoxemic values both with magnesium and in controls. There were no significant differences in these hormone concentrations between magnesium and the controls. CONCLUSION: Magnesium sulfate had no effect on fetal plasma concentrations of vasopressin, epinephrine, and norepinephrine during acute hypoxemia.

Animals↗