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Biomedical subjects

A Sato

Publications and source records attributed to A Sato.

At least 325 records · Page 18Linked to original sources
PubMed1998

Excitation of baroreceptors depresses A- and C-components of the somato-cardiac sympathetic reflex in anesthetized rats.

The effect of baroreceptor activation on somato-cardiac sympathetic reflex discharges was examined in urethane-anesthetized, vagotomized, and artificially ventilated rats. Single shock stimulation of myelinated (A) and unmyelinated (C) fibers in the tibial nerve of the left hindlimb elicited two separate excitatory reflex discharge components in a branch of the cardiac sympathetic nerve. They are termed the A- and C-components of the somato-cardiac sympathetic reflex discharges. When aortic nerves (AN) and carotid sinus nerves (CSN) were intact, a sudden increase in mean arterial blood pressure to about 150 mmHg induced by I.V. injection of phenylephrine (50 micro/kg) depressed the A- and C-components by up to 47 +/- 5.4 and 37 +/- 7.7% of the control values, respectively. However, bilateral sino-aortic denervation completely abolished the pressure-induced depression of both components. We conclude that baroreceptor afferent signals from the AN and CSN inhibit both A- and C-components of the excitatory somato-cardiac sympathetic reflex discharges. This and other previous evidence mentioned in the text indicate that inhibitory cardiac sympathetic reflexes originating from arterial baroreceptors and excitatory ones originating from somatic afferents interact, probably at the brainstem.

Anesthetics, Intravenous↗
PubMed1998

Beneficial impact of ramipril on left ventricular hypertrophy in normotensive nonalbuminuric NIDDM patients.

OBJECTIVE: To evaluate the effect of the ACE inhibitor ramipril as compared with placebo on left ventricular mass index (LVMI) in normotensive, nonalbuminuric NIDDM patients with left ventricular hypertrophy (LVH). Patients with NIDDM are characterized by excessive cardiovascular morbidity and mortality, and LVH, an independent risk factor for cardiac events, is often present in NIDDM patients. RESEARCH DESIGN AND METHODS: A total of 38 normotensive, nonalbuminuric (albuminuria < 100 mg/24 h) NIDDM patients with LVH (LVMI > 131 g/m2 in men and > 100 g/m2 in women) were enrolled in a 6-month randomized, double-blind parallel group study to compare the effects of ramipril (5 mg/day) with placebo on LVMI (echocardiography, Vingmed CFM725, Diasonics Sonotron), QTc dispersion determined as the interlead variation in QTc interval on standard electrocardiogram (ECG), and 24-h ambulatory blood pressure (A&D TM2420, Tokyo, Japan). A total of 16 ramipril (10 men, 60 +/- 9 years [mean +/- SD]) and 15 placebo-treated (8 men, 55 +/- 10 years) patients completed the study, and their data are presented. RESULTS: Ambulatory blood pressure was almost identical at baseline (132/76 +/- 3/1 vs. 133/74 +/- 5/2 mmHg [mean +/- SEM]) and remained stable during follow-up (134/76 +/- 3/1 vs. 136/74 +/- 6/2 mmHg) in the ramipril and placebo group, respectively. LVMI was comparable at baseline (137.1 +/- 7.0 vs. 129.6 +/- 3.7 g/m2) in the ramipril and placebo group, respectively, and decreased significantly more in the ramipril group as compared with the placebo group (17.6 +/- 3.0 vs. 5.7 +/- 4.6 g/m2, respectively, 11.9 [0.7-23.1] g/m2, mean difference [95% CI]; P = 0.037). QTc dispersion was comparable at baseline (60.2 [5.5] vs. 64.1 [6.5] ms) and did not change significantly during follow-up: -2.5 [7.0] vs. -12.2 [9.5] ms; mean difference 9.8 (-14.2 to 33.8 ms) in the ramipril and placebo group, respectively. CONCLUSIONS: Ramipril induces regression of LVH in normotensive, nonalbuminuric NIDDM patients, independent of reduction in systemic blood pressure.

Aged↗
PubMed1998

Increased left ventricular mass in normotensive type 1 diabetic patients with diabetic nephropathy.

OBJECTIVE: Diabetic nephropathy increases the risk of premature cardiovascular disease and sudden death, particularly in type 1 diabetic patients. One possible mechanism for this risk may be left ventricular hypertrophy. In our study, we aimed to evaluate left ventricular structure and function in normotensive type 1 diabetic patients with and without nephropathy. RESEARCH DESIGN AND METHODS: M-mode and Doppler echocardiography was performed in 17 type 1 diabetic patients with nephropathy (albuminuria [median (range)], 345 (135-2,846) mg/24 h) and compared with 34 normotensive, normoalbuminuric (10 [3-30] mg/24 h) type 1 diabetic patients matched for arterial blood pressure (mean +/- SD) ([134/77] +/- [13/7] vs. [129/78] +/- [12/7] mmHg), age (40 +/- 11 vs. 42 +/- 10 years), duration of diabetes (28 +/- 7 vs. 28 +/- 6 years), and BMI (24.2 +/- 4.2 vs. 24.6 +/- 2.4 kg/m2). RESULTS: Left ventricular mass (LVM) index was significantly higher in patients with nephropathy compared with patients with normoalbuminuria (100.8 +/- 10.3 vs. 88.2 +/- 21.0 g/m2, respectively; P = 0.02). Greater ventricular septum width was demonstrated in the nephropathic group compared with the control group (9.4 +/- 1.0 vs. 8.2 +/- 1.3 mm, respectively; P = 0.002). No significant difference in posterior wall thickness was apparent. The nephropathic group tended to have reduced diastolic function (E/A ratio, 1.2 +/- 0.3 vs. 1.4 +/- 0.4; P = 0.09). Fractional shortening was normal and about the same in the two groups. The groups did not differ with respect to serum creatinine or hemoglobin, while metabolic control (assessed by HbA1c) and plasma renin and prorenin levels were elevated in the nephropathic group compared with the normoalbuminuric group. CONCLUSIONS: A blood pressure-independent increase in LVM may contribute to the increased cardiac morbidity and mortality in normotensive type 1 diabetic patients with diabetic nephropathy. Glycemic abnormalities and activation of the renin-angiotensin system may lead to the ventricular enlargement.

Adult↗
PubMed1998

Primary cutaneous T-cell lymphoma involving the cheek: an infant case with a unique clinicopathologic feature.

We report a clinicopathologic feature of primary cutaneous T-cell lymphoma (CTCL) in a five-year-old boy with increasing swelling of his cheek since two years of age. Histologically, an infiltrate of atypical lymphoid cells with mature T-cell phenotype and clonality was prominent from the dermis to the subcutaneous tissue of the cheek. Although little effect was seen with aggressive multidrug-combined chemotherapy, therapy with interferon-alpha and steroids achieved a prolonged remission. This patient may provide important clues to understanding the clinicopathologic feature of rare primary CTCL in young children.

Cheek↗
PubMed1998

A novel bone resorption inhibitor, A-75943 isolated from Streptomyces sp. SANK 61296.

A novel bone resorption inhibitor, A-75943, was isolated from Streptomyces sp. SANK 61296. Its structure was determined to be (1"S,2'R,3"S,4S',5"S)-2-[(3",5"- dimethyl-2"-oxocyclohexan-1"-yl)-6'-oxotetrahydropyran-4'-yl ]acetamide by spectral analyses and chemical conversion of cycloheximide. A-75943 inhibited bone resorption in vitro in a concentration-dependent manner with an IC50 of 0.35 microM, and also displayed an inhibitory effect on bone resorption in thyroid and parathyroid-extracted rats.

Animals↗
PubMed1998

B-90063, a novel endothelin converting enzyme inhibitor isolated from a new marine bacterium, Blastobacter sp. SANK 71894.

A novel endothelin-converting enzyme (ECE) inhibitor, B-90063, was isolated from the culture supernatant of the newly discovered marine bacterium Blastobacter sp. SANK 71894. Based on spectral analyses and chemical reactions, the structure of B-90063 was determined to be bis[6-formyl-4-hydroxy-2-(2'-n-pentyloxazol-4'-yl)-4-pyridon -3-yl]-disulfide (1a). Human and rat ECEs were inhibited more potently by B-90063, with respective IC50 values of 1.0 and 3.2 microM, than were other neutral endopeptidases such as NEP and type-I and -IV collagenases. B-90063 also inhibited the binding of ET-1 to rat ET(A) and bovine ET(B) receptors, though its antagonistic activities were weak. B-90063, thus, may abolish the physiological actions of endothelins through the ECE inhibitory and receptor antagonistic mechanisms.

Animals↗
PubMed1998

[A clinical study of causes of death from active pulmonary tuberculosis with chemotherapy].

We evaluated retrospectively the causes of death from active pulmonary tuberculosis by the review of records and chest radiograohs of 364 patients (male 282, female 82) with active pulmonary tuberculosis, who were admitted to our hospital during 1995 to 1998. 43 patients (male 33, female 10) were died under anti-tuberculous chemotherapy. 20 cases were tuberculous death; death from acute progression of tuberculosis without response to chemotherapy (acute progression group) in eight cases and death from debility in spite of partial response to chemotherapy (debility group) in eight cases. 23 cases were died from underlying diseases; death from malignant neoplasmas (malignant group) in nine cases and death from complication of bacterial pneumonia (pneumonia group) in seven cases. In acute progression group, the age (mean +/- SE) was 64.8 +/- 5.2 years old and the survival period from admission was 11.8 +/- 4.2 days. Five cases were laborer or unemployed. This group was characterized with far advanced diseases presenting extensive lung lesions complicated with DIC or hepatic dysfunction, low performance status (PS), severe malnutrition and lymphocytepenia. In debility group, the age was 70.8 +/- 3.9 years old and the survival period from admission was 254.6 +/- 90.7 days. Five cases were laborer or unemployed. This group was characterized with multiple underlying diseases, low PS, previous anti-tuberculous chemotherapy and resistance to INH and/or RFP. In malignant group, the age was 69.3 +/- 3.2 years old and the survival period from admission was 99.9 +/- 21.2 days. This group was characterized with relatively well nourished, relatively good PS in comparison with other groups, and lymphocytepenia. In pneumonia group, the age was 82.8 +/- 1.7 years old and the survival period from admission was 153.3 +/- 54.5 days. This group was characterized with remarkably advanced age, low PS related to underlying disorders of central nervous system. In the causes of death with active pulmonary tuberculosis under chemotherapy, inhomogenous groups were included. Extensive disease, low PS, malnutrition, lymphocytopenia, previous chemotherapy, resistance to INH and/or RFP, and poorer social circumstances seemed to be risk factors for tuberculous death. In contrast, underlying malignant nepolasma, lower PS, and far advanced age were seemed to be the risk factors for non-tuberculous death.

Aged↗
PubMed1998

A twenty-year period in mass screening for uterine cervical cancer in Fukushima Prefecture.

To explore the change in age distribution of patients with uterine cervical cancer and its precursors, we analyzed 2,168,923 women in a series of mass screening for uterine cervical cancer in Fukushima Prefecture. The first examination rate was not increased over a 20-year period. During the screening period, severe dysplasia was found in 693 women, carcinoma in situ in 672 women, microinvasive carcinoma in 517 women, and frank invasive carcinoma in 421 women. The numbers of patients with frank invasive carcinoma was decreased gradually in every age group, which might reflect the effectiveness of our mass screening project. Although the detection rates of severe dysplasia, carcinoma in situ and microinvasive carcinoma have not changed in patients groups over 40 years old, the detection rates were increased in patients under the age of 39. These results may reflect a recent tendency for cervical cancer to increase in young women. It is important, therefore, to increase the screening rate for young women to prevent the progression with advanced cervical cancer.

Adult↗
PubMed1998

[New methods for measuring atlanto-axial vertical subluxation in rheumatoid arthritis by MR imaging].

We proposed two new methods of measuring atlanto-axial vertical dislocation in rheumatoid arthritis by MR imaging. One is the distance from the subdental synchondrosis of the axis to the diameter of the ring of the atlas. The other is the distance from the midpoint of the anteroposterior ends of the inferior margin of the axis to the diameter of the ring of the atlas. Values were also determined by the Ranawat method and the Redlund-Johnell method. There was good correlation between values determined by the new methods and those determined by the Ranawat method and Redlund-Johnell method.

Adolescent↗
PubMed1998

[A case of pulmonary tuberculosis complicated with intracranial tuberculous abscess].

A 75-year-old male was admitted to our hospital with complaints of fever and cough. Chest X-ray showed infiltrative shadows with cavity, and sputum smears were positive for acid-fast bacilli. About 2 months after the initiation of anti-tuberculous chemotherapy, suddenly generalized convulsion occurred. CT of the brain showed the solitary mass with the ring enhancement in the left subcortical area. About 4 weeks later, brain aspiration drainage was performed and pus was aspirated. He was diagnosed as intracranial tuberculous abscess. After the drainage, neurological symptoms disappeared completely and there were no recurrence of abscess. Attention should be called to the complication of intracranial tuberculosis, especially in cases worsened during anti-tuberculous chemotherapy.

Aged↗
PubMed1998

Development of occupational exposure limits in Japan.

The development of occupational exposure limits (OELs) in Japan is discussed by describing the OELs of two chemical compounds, benzene and trichloroethylene, as typical examples. As for benzene, sufficient epidemiological evidence has accumulated indicating that benzene is a human carcinogen. To establish the OEL for benzene, the OEL committee of the Japan Society for Occupational Health (JSOH) selected 9 cases of acute myeloic or monocytic leukemia out of the 14 cases of leukemia in the Pliofilm cohort, adopted the exposure estimate of Paustenbach et al. (52), and calculated the risk of benzene-induced leukemia by means of an average relative risk model. The lifetime risk of leukemia by exposure to benzene at 1 ppm for 40 years was calculated as 0.762 x 10(-3) with a 95% confidence interval between 0.621 x 10(-3) and 0.98.10(-3). The benzene level that causes one lifetime excess death from leukemia among 1,000 workers exposed to benzene for 40 years was 1.31 ppm, with a 95% confidence interval between 1.01 and 1.61 ppm. The OEL committee decided that benzene exposure should be controlled by a reference value corresponding to a lifetime risk (10(-3) or 10(-4)) of leukemia rather than by a time-weighted average (TWA) concentration. The committee has proposed that the benzene exposure level corresponding to the lifetime risk of 10(-3) is 1 ppm and that corresponding to the risk of 10(-4) is 0.1 ppm. In 1995, the International Agency for Research on Cancer (IARC) changed the carcinogenicity classification of trichloroethylene from Group 3 (not classifiable as to carcinogenicity to humans) to Group 2A (probably carcinogenic to humans). The OEL committee of the JSOH, however, reached the conclusion that since it has not been confirmed that trichloroethylene is a human carcinogen, and since carcinogenicity, if any, may be based on an epigenetic rather than genotoxic mechanism, it is not appropriate to establish the OEL of trichloroethylene presupposing that trichloroethylene is a carcinogen. The judgment of the OEL committee is that the OEL for trichloroethylene should be established on other than carcinogenicity findings, particularly on the basis of its neurological effects. In the light of accumulated evidence that a long-term exposure to trichloroethylene at 50 ppm will cause neurotoxic effects to industrial workers, the OEL committee has proposed 25 ppm (135 mg/m3) as a reference value for work environments. Finally, we propose that the general environmental air standards of benzene and trichloroethylene should be about 1/1,000 of the respective reference values for work environment.

Animals↗
PubMed1998

[Cancer chemotherapy in patients of advanced age (over 75)].

Generally, elderly patients are excluded from therapeutic trials because of decreased tolerance to chemotherapy. We discussed chemotherapy cancer patients of an advanced age based on our experience of malignant lymphoma and advanced gastric cancer patients over 75 years of age. We found the tendencies for diagnosis at more advanced stages involved many complications, especially 10% of cases have double cancer, and not good performance status in these patients. Some 53 cases of malignant lymphoma were treated with combination chemotherapy including anthracycline, obtained prolongation of survival in responder. On the other hand, 64 cases of advanced gastric cancer were treated with palliative chemotherapy. Some clinical trials have showed that older and younger patients were no different in terms of response, toxicity and overall survival. But these selected elderly patients could be entered in clinical trials, seemed to have to have surprisingly good health, no historical complications and good performance status, in spite of suffering from cancer. Not only chronological age but also the kinds of cancer and performance status are important justification for decisions to limit or withhold treatment.

Aged↗
PubMed1998

[A case of corneal abscess with impetigo contagiosa].

Impetigo contagiosa often occurs on the face of children. Although the eyelid and conjunctiva are frequently affected, no corneal involvement has been reported in Japan. We encountered a case of impetigo contagiosa with corneal abscess. The patient, an 8-year-old boy, complained of pain and presented with corneal abscess and iritis in the right eye as well as eruptions in the inferior eyelid and around the anterior nostrils. He was diagnosed as having impetigo contagiosa with corneal abscess. Because the corneal abscess and eruptions occurred at the same time and coagulase-positive Staphylococcus with identical drug sensitivity was isolated from both lesions, we considered the corneal lesion as a part of the impetigo contagiosa. When impetigo contagiosa occurs around the eye, especially on the eyelids, a careful examination of the anterior segment of the eye is needed.

Abscess↗
PubMed1998

Cloning of major histocompatibility complex (Mhc) genes from threespine stickleback, Gasterosteus aculeatus.

The threespine stickleback Gasterosteus aculeatus is an important model in evolutionary and ethologic studies. Its utility would greatly be increased by the availability of molecular markers distinguishing individuals and populations. Such markers can be provided by the major histocompatibility complex (Mhc) genes, which are well known for their extensive polymorphism. In the present study, both class I and class II B Mhc genes have been identified and sequenced. Fifteen distinct class I exon 2 and exon 3 sequences were obtained and assigned to 12 loci on the basis of intron 2 length differences. Some of the loci appear to be related to class I loci identified previously in cichlid fish. The intron 2 sequences and insertions/deletions in exon 2 group the loci into three families (with one family divided further into two subfamilies) derived from different ancestral genes. The ancestors presumably diverged from one another before the divergence of Gasterosteiformes from Perciformes. The 12 distinct class II B sequences may be derived from six loci, which are, however, closely related to one another in both exonic and intronic parts and may have diverged from a single common ancestor after the divergence of Gasterosteiformes from Perciformes. The intron 2 of some of the class I genes contains two microsatellites that can be used as markers, in addition to the polymorphism of the Mhc genes in their exonic regions.

Amino Acid Sequence↗
PubMed1998

[Clinical evaluation on causes of death in patients with pulmonary tuberculosis during the past 3 years (1994 to 1996)].

We evaluated the cause of death in patients with pulmonary tuberculosis during the past 3 years (1994 to 1996). Of 502 tuberculous patients, 58 (11.6%) patients died. Most of them were aged or under poor nutritional conditions. Of 378 active tuberculous patients, 39 (10.3%) patients died (group A). Of 124 old tuberculous patients or cases with extensive sequelae of tuberculosis, 19 (23.4%) patients died (group B). In the group A, 15 patients died in spite of improvements in tuberculosis lesions. All the intubated patients with active tuberculosis died. In the group B, most of patients died of respiratory failure or pneumonia.

Adult↗
PubMed1998

[Total intravenous anesthesia with propofol is advantageous than thiopental-sevoflurane anesthesia in the recovery phase].

A randomized, prospective and multi-institutional study was performed to investigate whether different anesthetic methods affected differently the quality of recovery from anesthesia. Two hundred and eleven patients were allocated to one of two groups; total intravenous anesthesia (TIVA) with propofol and fentanyl (group P, n = 107) and general anesthesia with thiopental, sevoflurane and nitrous oxide (group TS, n = 104). The rapidity of emergence from anesthesia and postoperative incidence of nausea, vomiting, and headache were compared between the two groups. The group P showed significantly shorter emergence times for verbal command responses (7.4 +/- 5.6 min), extubation (10.0 +/- 6.0 min) and orientation (13.1 +/- 7.8 min) than the group TS (9.1 +/- 5.0 min, 11.7 +/- 6.2 min, 16.4 +/- 7.9 min, respectively). The postoperative incidence of vomiting was not significantly different between the two groups (3.7% in the group P and 9.6% in the group TS), but the postoperative incidences of nausea and headache were significantly lower in the group P compared with the group TS (10.3%, 17.8%, respectively in the group P and 34.6%, 29.8%, respectively in the group TS). We conclude that TIVA with propofol is advantageous than thiopental-sevoflurane anesthesia in the recovery phase.

Adult↗
PubMed1998

Cells in the duct system of the rat submandibular gland.

The duct system of the rat submandibular gland (granular convoluted tubule [GCT], striated duct, excretory duct, main excretory duct [MED] and salivary bladder) was studied using scanning and transmission electron microscopy, with special reference to the dark and tuft cells. The MED was subjected to histochemistry for horseradish peroxidase (HRP) uptake. The epithelium of the duct system was composed of a heterogeneous cell population. On scanning electron-microscopic observation, principal, dark, and tuft cells were easily distinguished by their microvilli. Principal cells had small microvilli and microridges on their surface. The principal cells of the striated duct had secretory granules in the apical cytoplasm, but those of the excretory duct, the MED, and the salivary bladder had electron-lucent vesicles. Except for the GCT and salivary bladder, the basal infoldings of the epithelial cells were well developed. The dark cells were characterized by regular microvilli, and many tubules and vesicles confined to the apical cytoplasm. They existed in the striated duct, the excretory duct, the MED, and salivary bladder. The so-called pillar cells in the GCT appeared to be identical to the dark cells. Tuft cells had on their surface long, blunt microvilli with prominent rootlets. Many vesicles were observed in the apical cytoplasm. It was concluded that dark and tuft cells were common in the striated duct, the excretory duct, the MED and salivary bladder. Dark cells were observed also in the GCT. Dark and principal cells of the MED showed HRP uptake but tuft cells did not.

Animals↗