Biomedical subjects

T Shindo

Publications and source records attributed to T Shindo.

At least 73 records · Page 4Linked to original sources

PubMed1994

Nitric oxide synthesis in rat cardiac myocytes and fibroblasts.

We investigated nitric oxide (NO) synthase activity in cultured neonatal rat cardiac myocytes and fibroblasts upon treatment with interleukin 1 beta (IL-1 beta) and lipopolysaccharide (LPS). Incubation of cardiac myocytes for 24 h with IL-1 beta or LPS caused a significant increase in NO and cGMP production. Simultaneous incubation of IL-1 beta with NG-monomethyl-L-arginine or transforming growth factor beta (TGF-beta) completely inhibited the IL-1 beta-induced NO and cGMP production in cardiac myocytes. In contrast, incubation of cardiac fibroblasts for 24 h with IL-1 beta or LPS showed no significant effect on NO or cGMP production. Addition of IL-1 beta decreased the beating rate of cardiac myocytes, but TGF-beta overcame that inhibition. These observations suggest the presence of iNOS in cardiac myocytes, which is an important regulator of contractile function of the heart.

Amino Acid Oxidoreductases↗

PubMed1994

Increase in myocardial interstitial norepinephrine during a short period of coronary occlusion.

The neurally intact in vivo beating hearts of cats were used to examine the influence of a short period of coronary occlusion on regional myocardial norepinephrine levels. Using a cardiac dialysis technique, dialysate norepinephrine levels were measured as an index of myocardial interstitial norepinephrine levels, and the left anterior descending coronary artery was occluded for 10 min. In anesthetized cats, 10 min occlusion increased the dialysate norepinephrine level in the ischemic region but not in the non-ischemic region. To investigate the influence of neuronal norepinephrine uptake on occlusion-induced dialysate norepinephrine response, a neuronal uptake inhibitor (desipramine) was locally administered to both regions with the dialysis perfusate. In the ischemic region, 10 min occlusion significantly increased the dialysate norepinephrine level from the control level in the presence of desipramine. We concluded that 10 min coronary occlusion was associated with an increase in the myocardial interstitial norepinephrine level in the ischemic region. This increase in the early phase of ischemia was not attributed to attenuation of neuronal norepinephrine uptake function.

Animals↗

PubMed1994

beta-Adrenergic mechanisms attenuated hypoxic pulmonary vasoconstriction during systemic hypoxia in cats.

In this study, we examined how locally mediated hypoxic pulmonary vasoconstriction is modulated by autonomic nervous system activation during global alveolar hypoxia (GAH) accompanied by systemic hypoxemia. Using an X-ray television system on the in vivo cat lung, we measured changes in the internal diameter (ID) during GAH and regional alveolar hypoxia (RAH) without systemic hypoxemia in identical small pulmonary arteries and veins (100-600 microns ID). We also analyzed the effects of the autonomic nervous system blockade on the hypoxic ID changes. During GAH the ID of the arteries reduced by 5 +/- 1 and 3 +/- 1% with 10 and 5% O2 inhalations, respectively, whereas during RAH the arterial ID reduced by 12 +/- 1 and 18 +/- 1% with 10 and 5% O2 inhalations, respectively. The magnitude of the ID reduction was significantly smaller during GAH than during RAH. After pretreatment with propranolol, however, GAH induced large ID reductions (16 +/- 1 and 23 +/- 1% with 10 and 5% O2 inhalations) with patterns very similar to those seen during RAH. Phentolamine and atropine had no effect on the response during GAH. The ID reductions during RAH, on the other hand, were unaffected by all the blockers. The results indicate that, in the cat, alveolar hypoxia per se acts locally to constrict the small pulmonary vessels and that the hypoxic vasoconstriction is attenuated by a beta-receptor-mediated vasodilator effect during GAH with systemic hypoxemia. In addition, we found that, after adrenalectomy plus ganglion blockade with hexamethonium bromide, the GAH-induced ID reduction with 5% O2 inhalation was enhanced from 3 to 19%.(ABSTRACT TRUNCATED AT 250 WORDS)

Adrenal Glands↗

PubMed1994

[A case of multifocal eosinophilic granuloma presenting as a rib tumor].

A 19-year-old man was hospitalized because of left chest pain. He had a tumor in the left fifth rib with tenderness. Partial resection of the fifth rib was performed. Pathological examination showed granuloma with infiltration of histiocyte-like cells and eosinophils, and S-100 staining was positive. Therefore, the rib tumor was diagnosed as eosinophilic granuloma. Thereafter, the patient had recurrent bone lesions of the mandible, temporal bone, zygomatic bone, scapula, right eleventh rib, and tibia. Radiation therapy was effective for local treatment of each bone lesion. Moreover, pulmonary lesion was suspected on roentgenographic study. However, he had no respiratory symptoms and there was no significant change on roentgenographic findings over six years. It was considered that follow up for detection of bone and pulmonary lesions should be continued in this case.

Adult↗

PubMed1993

The amplitude of synchronized cardiac sympathetic nerve activity reflects the number of activated pre- and postganglionic fibers in anesthetized cats.

In order to obtain information regarding the number of pre- and postganglionic fibers that are firing, we measured cardiac sympathetic nerve activity (CSNA) before and after the successive sectioning of T1-T5 thoracic rami in anesthetized cats. Total activity from the area was measured under the mean CSNA curve. Peak amplitude, width and periodicity of the synchronized discharge was analyzed from the CSNA curve by the method we developed. Total CSNA decreased to 91 +/- 6%, 63 +/- 6%, 27 +/- 10%, 8 +/- 6% and < 1% of the control due to successive section of the T5, T4, T3, T2 and T1 rami, respectively. The peak amplitude of synchronized CSNA decreased to 95 +/- 6%, 73 +/- 8%, 40 +/- 5% and < 10% of the control value, due to section of the T5, T4, T3 and T2 rami, respectively. The control width was 107 +/- 8 ms and decreased to 106 +/- 1 ms, 92 +/- 6 ms and 68 +/- 5 ms by successive section of the respective T5, T4 and T3 rami. However, periodicities of 80-120 ms (Tc rhythm) and 140-500 ms (Tb rhythm) of synchronized CSNA remained unchanged after section of the T3-T5 rami. The total CSNA decreased gradually due to decreases in the peak amplitude and width of synchronized CSNA with the successive section of preganglionic fibers. These results indicate that the peak amplitude of synchronized CSNA reflects the number of pre- and post-ganglionic fibers that are firing and suggest that the number of preganglionic neurons which activate the cardiac fibers naturally was largest in the T3 segment.(ABSTRACT TRUNCATED AT 250 WORDS)

Anesthesia↗

PubMed1993

Nitric oxide mediates cat hindlimb cholinergic vasodilation induced by stimulation of posterior hypothalamus.

The aim of this work was to examine whether endothelium-derived relaxing factor (nitric oxide) mediates cat hindlimb cholinergic vasodilation induced by stimulation of the posterior hypothalamus and beta-adrenergic vasodilation by I.V. injection of isoproterenol using an inhibitor of nitric oxide synthesis, NW-nitro-L-arginine methyl ester (L-NAME). Without L-NAME, femoral blood flow velocity (FBV) increased during hypothalamic stimulation by 11.2 +/- 2.2 cm/s (mean +/- SEM) from the baseline value of 8.4 +/- 2.2 cm/s and femoral conductance (FC) increased by 0.084 +/- 0.021 cm/s/mmHg from 0.062 +/- 0.016 cm/s/mmHg, which were abolished by atropine (0.5 mg I.A.). Arterial blood pressure (AP) and heart rate (HR) increased during hypothalamic stimulation (15 +/- 8 mmHg and 22 +/- 6 beats/min). When isoproterenol (1-2 micrograms I.V.) was injected, FBV and FC increased 5.1 +/- 0.56 cm/s and 0.048 +/- 0.005 cm/s/mmHg. With L-NAME (20-100 mg I.A.), the rises in AP and HR during hypothalamic stimulation were unchanged but the increases in FBV and FC were significantly blunted to 5.2 +/- 3.7 cm/s and 0.026 +/- 0.021 cm/s/mmHg. In contrast, L-NAME did not affect the responses in FBV and FC during stimulation of beta-adrenergic receptors. The effect of NG-monomethyl-L-arginine (10-30 mg I.A.) was the same as L-NAME. It is suggested that nitric oxide is involved in hindlimb cholinergic vasodilation neurally induced by hypothalamic stimulation but not in beta-adrenergic vasodilation.

Animals↗

PubMed1993

Selective and tone-dependent vasodilation of arterial segment in rabbit and feline pulmonary microcirculation in response to ANP.

Using an X-ray television system, we directly measured the changes in internal diameter (ID; 100-600 microns) of small pulmonary arteries and veins in response to intravenous infusion of atrial natriuretic peptide (ANP) in anesthetized rabbits and cats. Under physiological conditions, ANP (0.01-1 micrograms/(kg.min) for 3 min) increased the ID of the small arteries in a dose-dependent manner by 4-9% and by 6-14% in the rabbit and cat, respectively. The maximum increase in ID occurred in the 400-600 microns arteries. In the small veins, however, the peptide had no significant effects on the ID. To simultaneously investigate the ANP-induced responses of pulmonary vessels with different vascular tone in a given lung region, we embolized a part of the rabbit pulmonary vascular tree with micro-beads (80-100 microns diameter) and measured ID responses to ANP (1 microgram/(kg.min) for 3 min) in the embolized vessels with elevated tone and the nonembolized vessels with baseline tone. In the embolized arteries, which had constricted by 31%, ANP induced 27% increase in ID, while in the nonembolized arteries it caused 8% increase in ID. This indicated that in the small arteries, the vasodilator activity of ANP is greatly enhanced under the conditions of elevated vascular tone. In the small veins, however, no significant vasodilation occurred even under the elevated-tone conditions. We concluded that ANP dilates the arterial segments in the rabbit and cat pulmonary microcirculation selectively and in a dose-dependent manner. Furthermore, the pulmonary vasodilator effect of ANP was dependent on the pulmonary vascular tone.

Animals↗

PubMed1993

[Clinical application of the thoracic balloon for postpneumonectomy patients].

Pneumonectomy may result in complications such as continuous intrathoracic bleeding and mediastinal shift. We used a thoracic balloon made of silicone rubber in 15 postpneumonectomy patients in an attempt to prevent such complications. Two types of thoracic balloons were used in our series. Type 1 thoracic balloon is a simple balloon requiring cooperation with a drainage tube, and Type 2 is a combination balloon and drainage tube. During surgery, air was injected into the thoracic balloon through an air filter. After removal of the thoracic balloon, infusion of sulfur hexafluoride, SF 6, into the thoracic cavity was performed on the 7th to 10th postoperative days. Placement of thoracic balloons in the pleural space after pneumonectomy is a simple, safe and useful method of preventing both intrathoracic bleeding and mediastinal shift.

Aged↗

PubMed1993

[Postoperative lung function in patients with funnel chest].

We evaluated the postoperative lung function determined by spirometry in 54 patients with funnel chest (48 males and 6 females: age range, 4-18 years). Thirty-one patients had sternal turnover as corrective surgery, while 23 had sternal elevation with absorbable PLA (polylactic acid) strut. The mean value of vital capacity as a percentage of predicted (%VC) was 97.3% before operation. %VC was decreased at 3 months (80.5%), 6 months (87.4%), 12 months (82.8%), 24 months (85.9%), and 36 months (77.7%) after the operation (p < 0.01). In patients who had sternal elevation, %VC was decreased at 3 months but not at 6 months, 12 months, 24 months, or 36 months after the operation, while %VC was decreased at any point after the operation in patients who had sternal turnover. No significant changes were seen in forced expiratory volume in one second as a percentage of predicted (FEV1.0%), nor in the ratio of residual volume to total lung capacity (RV/TLC). In conclusion, sternal elevation with PLA strut is a better corrective surgery for funnel chest than sternal turnover, because of its less lung function loss after the operation.

Adolescent↗

PubMed1993

[A case of mediastinal neurinoma originated from the left vagal nerve].

A 46-year-old man was admitted to our hospital because of an abnormal shadow on the chest roentgenogram. The operation was performed through left posterolateral thoracotomy. A tumor mass, 4.5 x 2.5 x 2.5 cm in size, was found and its origin was the left main vagal nerve 0.5 cm distal the branching root of the recurrence nerve. The tumor and a part of the left vagal nerve was resected en bloc. Pathological study revealed tha the tumor was neurinoma of Antoni A+B. Postoperative course was uneventful. This is the 34th reported case in Japanese literature of neurinoma with its origin from the intrathoracic vagal nerve.

Cranial Nerve Neoplasms↗

PubMed1993

[Surgical treatment of metastatic lung tumors].

From January 1970 to March 1991, 72 operations in 55 patients (31 males and 24 females) with metastatic lung tumors were performed in our department. Their cumulative survival rates was 25.5% at five years. With analysis of the various prognostic factors, patients both with solitary metastases and without lymph node metastases had a good prognoses. However, even in patients with recurrent lung metastatic tumors, long time survival was achieved with reoperation in two patients. We concluded that reoperation with or without effective chemotherapies was effective in selected patients.

Adolescent↗

PubMed1992

A farnesyl arabinoside as an enhancer of glucose transport in rat adipocytes from a soft coral, Sinularia sp.

Separation of a lipophilic extract of a soft coral, Sinularia sp., assayed by enhancement of glucose transport in rat adipocytes, gave farnesyl 4-O-beta-D-arabinopyranosyl-beta-D-arabinopyranoside-2,2',3- triacetate (1a) whose structure was determined by spectroscopy. Enhancers of glucose transport may be useful for the prevention and treatment of diabetic disorders.

Adipose Tissue↗

PubMed1992

Efficient selection of mu m-mutants from mu m-expressing myeloma cells by treatment with ricin A-conjugated anti-mu antibody.

We have developed an efficient system for obtaining myeloma mutants defective in trans-acting factors required for immunoglobulin (Ig) gene expression. The system consists of a myeloma cell line designed for this purpose and an efficient method for selecting mutants from it. The cell line is X63.653 transfected with the mu gene, whose tailpiece sequence was replaced with the transmembrane sequence of human EGF receptor to hold mu on the cell surface and whose CH1 sequence was removed to prevent mu from being retained in the endoplasmic reticulum. It efficiently and stably expressed mu chains of IgM on the cell surface (mu m+) without light chains. To obtain mutants lacking mu m (mu m-) from the mu m+ cell line by selectively killing mu m+ cells, a method with ricin A-conjugated anti-mu antibody was more reliable than complement lysis mediated by anti-mu antibody. Applying the system, we obtained a variety of mu m- mutants.

Animals↗

PubMed1992

Statistical analysis of clinical risk factors for coronary artery spasm: identification of the most important determinant.

Coronary artery spasm plays an important role in acute ischemic events, and it has a close relationship with coronary atherosclerosis. Thus we attempted to determine the most significant risk factor for coronary artery spasm. Among 3000 consecutive patients who underwent coronary cineangiography with ergonovine maleate testing, 330 with typical angina pectoris (group 1) and 294 with old myocardial infarction (group 2) were studied. We divided each group into three or four subgroups according to the presence of fixed organic stenosis (FOS+) or a positive reaction to ergonovine maleate (coronary artery spasm [CAS]+). We examined the relationship between coronary artery spasm and eight coronary risk factors: age, sex, hypertension, diabetes mellitus, smoking, and serum cholesterol, uric acid, and high-density lipoprotein cholesterol levels. The proportion of smokers in the subgroups with CAS(+) was significantly higher than in the subgroups with CAS(-)(p less than 0.01). There was no correlation between smoking and fixed organic stenosis. According to the results of multiple regression analysis, there was a positive correlation between smoking and CAS(+) and between serum high-density lipoprotein cholesterol levels and CAS(+)(p less than 0.01). Thus we concluded that smoking is the most significant risk factor in discriminating between patients with and without coronary artery spasm.

Cholesterol, HDL↗

PubMed1992

[Irritable bowel syndrome in children].

The irritable bowel syndrome (IBS) is characterized by alteration in bowel habits (i.e., constipation and/or diarrhea) and abdominal pain, and is most common gastrointestinal disorder in adults. The recurrent abdominal pain (RAP) in children is similar to IBS in adults except bowel habits, but there is no settled conception of IBS in children. In our department, diagnosis of pediatric IBS will be made if the child has; #1 functional gastrointestinal disorders without organic diseases, #2 abdominal pain and other gastrointestinal symptoms continuing more than 3 weeks, #3 psychogenic background factors. We experienced 63 cases of IBS (23.5% in all 268 cases) from April 1990 to March 1992 at our pediatric digestive outpatient clinic. They ranged from 4 to 15 years old and about 60% of them were elder than 13 years old. Psychogenic factors were usually related to environment of school life and home. Careful history taking and routine examination were most important for the diagnostic approach. Management of this disease included counseling and drug therapy. Almost all cases reached much better condition 1 to 6 weeks after the therapy started. The combination therapy with psychologist was required in a few cases.

Adolescent↗

PubMed1992

[Pneumonectomy for destroyed lung or chronic tuberculous empyema].

Fourteen patients underwent pneumonectomy for destroyed lung or tuberculous empyema at the Shimada Municipal Hospital from September 1980 to December 1985. Mean age was 61 and ten patients were males. Cough and sputum (in 12 cases) and hemosputum or hemoptysis (in 8 cases) were common complaints. Three patients had complications in the immediate postoperative period: hemorrhagic shock, pulmonary embolism and contralateral pneumothorax. They were treated conservatively. The postoperative course was uneventful in the other patients and all complaints were reduced or disappeared. And lung function improved in 3 cases with chronic empyema compressing the mediastinum. In conclusion, pneumonectomy is one of the radical operation for destroyed lung or chronic tuberculous empyema with low pulmonary function and complaints. And the critical level are 40% of %VC and 25% of FEV1.0/pr. %VC in preoperative pulmonary function.

Adult↗

PubMed1992

[Flow cytometric analysis of platelets in patients with variant thrombasthenia].

Three cases of suspected variant thrombasthenia patients (out of 10 cases of Glanzmann's thrombasthenia), who had significant amounts of platelet GPIIbIIIa, underwent flow cytometry to analyse the binding capacity of monoclonal antibodies against GPIIbIIIa to platelets. The monoclonal antibodies used in this study were as follows: PLT-1 and AP-2 recognizing the IIbIIIa complex; TP 80, P2 and AP-4 recognizing IIb:;AP-5 recognizing IIIa;OP-G2, which binds an epitope near the RGD binding site and 3F11. OP-G2 also recognizes conformational changes of activated platelets by increased binding. Case 1 platelets showed a binding capacity of 28-63% of that of normal platelets for TP80, AP-2, AP-4, and 3F11, but no binding to OP-G2. Case 2 platelets also showed 16-44% binding with TP80, AP-2, AP-4, AP-5, and 3F11, but no binding to OP-G2. These findings indicated the presence of structural abnormalities of the functional site of platelet GPIIbIIIa in cases 1 and 2. Case 3 platelets bound with all monoclonal antibodies normally, but normal increase in the binding of OP-G2 to platelets activated by thrombin or ADP was not seen, indicating a lack of activation of the fibrinogen binding site of platelet GPIIbIIIa.

Adult↗

PubMed1991

Progression of coronary atherosclerosis: is coronary spasm related to progression?

A total of 239 patients undergoing serial coronary angiography with a concomitant ergonovine provocation test were studied between July 1974 and June 1987. The progression of coronary artery disease was evaluated in relation to risk factors, especially coronary artery spasm. Patients were classified into three groups: 1) new myocardial infarction group (39 patients); 2) progression without infarction group (90 patients); and 3) nonprogression group (110 patients). To assess how risk factors and coronary spasm are related to the occurrence of new myocardial infarction and progression without infarction, 11 variables in the three groups were examined: age, gender, the time interval between the studies, fasting blood sugar, systolic blood pressure, diastolic blood pressure, smoking, serum cholesterol, triglyceride, uric acid and a positive response to the ergonovine provocation test. Multiple regression analysis selected three independent predictors of progression without infarction: cholesterol (p less than 0.01), systolic blood pressure (p less than 0.05) and a positive response to the ergonovine provocation test (p less than 0.001). Multiple regression analysis also selected three independent predictors of the occurrence of new myocardial infarction: fasting blood sugar (p less than 0.01), systolic blood pressure (p less than 0.05) and a positive response to the ergonovine provocation test (p less than 0.001). A positive response to the ergonovine provocation test was the strongest factor for occurrence of both new myocardial infarction and progression without infarction. To evaluate segmental arterial changes, 3,275 coronary artery segments were analyzed in the 239 patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Cardiac Catheterization↗