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K Chida

Publications and source records attributed to K Chida.

At least 91 records · Page 5Linked to original sources
PubMed1998

Effects of chemical stimulation of the rostral ventrolateral medulla on cerebral and renal microcirculation in spontaneously hypertensive rats.

We investigated whether microcirculatory responses elicited by excitation of intrinsic neurons in the rostral ventrolateral medulla (RVLM) are altered in spontaneously hypertensive rats (SHR). SHR and Wistar-Kyoto rats (WKY) were anesthetized with chloralose, paralyzed with tubocurarine, and artificially ventilated. Cerebral and renal blood flows (CBF and RBF) were simultaneously measured using laser-Doppler flowmetry. Chemical stimulation of the RVLM neurons by microinjection of L-glutamate increased arterial pressure (AP) and heart rate in both SHR and WKY. Stimulation of the RVLM neurons also elicited stimulus-locked increase in CBF and decrease in RBF in both groups. The % changes in CBF and RBF were dose-dependent as stimulus intensity was increased and did not differ significantly between the SHR and WKY groups. Cerebral and renal vascular resistance (CVR and RVR) levels were calculated from changes in CBF or RBF and those in mean AP. The percent reduction in CVR and percent elevation in RVR were dose-dependent and did not differ significantly between the two groups. The data indicate that cerebral and systemic microcirculatory responses elicited by excitation of the RVLM neurons do not differ between SHR and WKY.

Animals↗
PubMed1998

Fibroblasts as target and effector cells in Japanese patients with sarcoidosis.

Fibroblasts play a crucial role in progressive lung fibrosis, acting not only as target cells but also as effector cells. To clarify these functions in sarcoidosis, lung fibroblasts from Japanese sarcoid patients were studied for their proliferative capacity and cytokine productivity. Fibroblasts were cultured from transbronchial lung biopsy specimens from seven patients with sarcoidosis. As a comparison, fibroblasts from open lung biopsy specimens of four patients with idiopathic pulmonary fibrosis (IPF) were studied. For controls, fibroblasts were cultured from specimens of normal resected lung tissue of five patients with localized lung cancer. The proliferative activity of cultured fibroblasts from patients with sarcoidosis was highest among the three groups (p < 0.05). However, the proliferative capacity in all groups was suppressed when fibroblasts were cultured with interleukin-1beta (IL-1beta). No significant differences were noted in the degree of inhibition among the three groups. Addition of interferon-gamma (IFN-gamma) also resulted in inhibition of fibroblast growth in all groups, but the degree of inhibition was significantly greater in both the sarcoid and IPF groups than in controls (p < 0.05). The amount of interleukin-6 (IL-6) in the culture supernatants from sarcoid fibroblasts cocultured with IL-1beta was significantly higher than in controls. Sarcoid fibroblasts are not only proliferatively active but also possess effector cell function to produce cytokines. IL-6 may enhance the immunologic reaction to sarcoidosis and cause the disease to become chronic. IFN-gamma suppresses proliferation of sarcoid fibroblasts and may prevent fibrotic changes of the lungs in the Japanese sarcoid patients.

Adult↗
PubMed1998

Cholesterol sulfate activates transcription of transglutaminase 1 gene in normal human keratinocytes.

Cholesterol sulfate and transglutaminase 1 are essential for the process of keratinization. Cholesterol sulfate is formed during keratinization and activates the eta isoform of protein kinase C. Transglutaminase 1 is a key enzyme for formation of the cornified envelope in terminally differentiated keratinocytes. In this study, we demonstrated that cholesterol sulfate acts as a transcriptional activator of the transglutaminase 1 gene in normal human keratinocytes. Growth of normal human keratinocytes was inhibited by cholesterol sulfate, but not by its parental cholesterol. Treatment of normal human keratinocytes with cholesterol sulfate induced activity of transglutaminase 1 in a dose- and time-dependent manner. Activation of transcription of transglutaminase 1 by cholesterol sulfate was demonstrated by northern blotting analysis, whereas that by cholesterol was not. In order to identify a cholesterol sulfate responsive region in the transglutaminase 1 gene, plasmids were constructed containing a luciferase reporter gene ligated to deletion fragments of the 5' upstream region of the tranglutaminase 1 gene and were transfected into normal human keratinocytes. Transfected cells were treated with cholesterol sulfate, the phorbol ester 12-O-tetradecanoylphorbol-13-acetate and a high concentration of Ca2+. Our results indicate that the responsive element(s) for cholesterol sulfate and phorbol ester is located upstream of the human transglutaminase 1 gene at a position(s) between -819 and -549, whereas the responsive element for Ca2+ is located at a position between -79 and -49.

5' Untranslated Regions↗
PubMed1998

Phorbol ester-induced G1 arrest in BALB/MK-2 mouse keratinocytes is mediated by delta and eta isoforms of protein kinase C.

We investigated the possible negative regulation of the cell cycle by protein kinase C (PKC) isoforms in synchronously grown BALB/MK-2 mouse keratinocytes, in which PKC isoforms were overexpressed by using the adenovirus vector Ax. Cells at the G1/S boundary of the cell cycle were the most sensitive to the inhibitory effect of 12-O-tetradecanoylphorbol-13-acetate (TPA), a PKC agonist, resulting in G1 arrest. TPA-induced inhibition of DNA synthesis was augmented by overexpression of the eta and delta isoforms, but rescued by the dominant-negative and antisense eta isoforms. In contrast, the alpha and zeta isoforms showed no effect on DNA synthesis with or without TPA treatment. Immunoblotting indicated cell cycle-dependent expression of the eta isoform, being highest in cells at the G1/S boundary. The present study provides evidence that the eta and delta isoforms of PKC are involved in negative regulation of cell cycle at the G1/S boundary in mouse keratinocytes.

Adenoviridae↗
PubMed1998

Histological evidence for cell proliferation activity in cystic tumor (endodermal heterotopia) of the atrioventricular node.

Cystic tumor (endodermal heterotopia) of the atrioventricular (AV) node in a 95-year-old female is described. Electrocardiograms showed complete AV blockage with a narrow QRS morphology resulting from the long-standing first degree of AV blockage since age 61. A cardiac pacemaker was implanted at age 83. The patient died of pneumonia at age 95. Autopsy demonstrated a normal heart weight (320 g), normal coronary artery and normal myocardium. Histological examination of the conduction system revealed a marked fibrotic sinoatrial (SA) node and a cystic lesion in the lower right atrium, including the approaches to the AV node. The bundle of His and its branches were completely intact. Cellular nests and cystically dilated tubules were scattered within a loose tissue stroma, which measured 18 x 12 x 5 mm. There were several mitotic figures among the tubules, as well as nuclear fragments similar to apoptotic bodies and exfoliation of the tumor cells. Immunohistochemical studies demonstrated a positive reaction for epithelial membrane antigen, carcinoembryonic antigen, CA19-9, cytokeratin and secretory component in the tubular cells, and a negative reaction for thrombomodulin. Endocrine cells among the tubules were positive only for calcitonin and serotonin. Ultrastructurally, sparse microvilli and desmosome-like structures between the tumor cells were observed. These findings support that this lesion originates from the endoderm. Moreover, it is likely that progression in the degree of AV block may be explained by the cell proliferation activity of the tumor.

Aged↗
PubMed1998

[A case of solitary pulmonary nodule caused by Mycobacterium avium].

A 56-year-old male without respiratory symptoms, past history nor familial history, was admitted to our hospital because of pulmonary solitary nodule on the chest radiograph. Computed tomograph showed a smooth surface nodule in the left lower lobe (segment 8). Bronchofiberscopy could not give any specific histological findings nor bacteriological findings, therefore the patient underwent partial pulmonary resection by videoassisted thoracoscopic surgery. Pathology of the resected specimen revealed epithelioid cell granuloma with giant cells but not any acid-fast bacilli. He was treated with rifampicin and isoniazid for "tuberculoma". After three weeks, thirty colonies grew on an Ogawa's egg medium, which were identified as Mycobacterium avium by PCR. There are few reports about the solitary pulmonary nodule due to M. avium-intracellurale complex infection, however, it is supposed that there are many "tuberculoma's" without bacteriological differentiation between tuberculosis and nontuberculous mycobacterial infection. It is difficult to diagnose a solitary pulmonary nodule caused by nontuberculous mycobacterial infection with bronchofiberscopy, and the location of the lesion is usually subpleural, therefore it is thought that videoassisted thoracoscopic surgery is valied for the diagnosis of solitary pulmonary nodule due to nontuberculous mycobacterium.

Humans↗
PubMed1998

[Pulmonary tuberculosis with diabetes mellitus, presenting multiple nodular shadows].

An asymptomatic 52-year-old male, who was diagnosed as poorly controlled diabetes mellitus (DM), was referred to our hospital because of abnormal shadows on chest X-rays. Physical examinations and laboratory data showed no abnormal findings except increased values of blood sugar and HbA1c (12.1%). Chest X-ray and CT scan revealed multiple nodular shadows in both lung fields. The specimens from transbronchial biopsy showed epithelioid granuloma, and Mycobacterium tuberculosis was confirmed with bronchial wash fluid. The patient was then treated with antimycobacterial drugs and sulfonylurea along with diet therapy. The multiple nodular shadows gradually disappeared. It seemed that impaired host defense mechanisms caused by poorly controlled DM is responsible for the bronchogenic dissemination of M. tuberculosis, resulting in the extension into the multiple nodular shadows. Thus, a good control of DM is important for the prevention of an onset and excerbation of tuberculosis in patients with DM.

Diabetes Complications↗
PubMed1998

Induction of differentiation in normal human keratinocytes by adenovirus-mediated introduction of the eta and delta isoforms of protein kinase C.

Protein kinase C (PKC) plays a crucial role(s) in regulation of growth and differentiation of cells. In the present study, we examined possible roles of the alpha, delta, eta, and zeta isoforms of PKC in squamous differentiation by overexpressing these genes in normal human keratinocytes. Because of the difficulty of introducing foreign genes into keratinocytes, we used an adenovirus vector system, Ax, which allows expression of these genes at a high level in almost all the cells infected for at least 72 h. Increased kinase activity was demonstrated in the cells overexpressing the alpha, delta, and eta isoforms. Overexpression of the eta isoform inhibited the growth of keratinocytes of humans and mice in a dose (multiplicity of infection [MOI])-dependent manner, leading to G1 arrest. The eta-overexpressing cells became enlarged and flattened, showing squamous cell phenotypes. Expression and activity of transglutaminase 1, a key enzyme of squamous cell differentiation, were induced in the eta-overexpressing cells in dose (MOI)- and time-dependent manners. The inhibition of growth and the induction of transglutaminase 1 activity were found only in the cells that express the eta isoform endogenously, i.e., in human and mouse keratinocytes but not in human and mouse fibroblasts or COS1 cells. A dominant-negative eta isoform counteracted the induction of transglutaminase 1 by differentiation inducers such as a phorbol ester, 1alpha,25-dihydroxyvitamin D3, and a high concentration of Ca2+. Among the isoforms examined, the delta isoform also inhibited the growth of keratinocytes and induced transglutaminase 1, but the alpha and zeta isoforms did not. These findings indicate that the eta and delta isoforms of PKC are involved crucially in squamous cell differentiation.

Adenoviruses, Human↗
PubMed1998

Development of facial palsy during immunoadsorption plasmapheresis in Miller Fisher syndrome: a clinical report of two cases.

Immunoadsorption plasmapheresis (IAP) using a tryptophan linked gel column has been shown to effectively remove serum IgG anti-GQ1b antibody which may contribute to the pathogenesis of Miller Fisher syndrome. Two patients are reported on with Miller Fisher syndrome, who developed bilateral facial palsy during IAP using a tryptophan column, while ophthalmoplegia, ataxia, and, areflexia were improving. In these patients, the titre of anti-GQ1b antibodies was reduced. The IAP using a tryptophan column has a beneficial effect on Miller Fisher syndrome but may not inhibit the development of facial palsy. The mechanism of such a dissociated effect of IAP on Miller Fisher syndrome is discussed.

Aged↗
PubMed1998

Diffuse panbronchiolitis and rheumatoid arthritis-associated bronchiolar disease: similarities and differences.

There is a considerable overlap between diffuse panbronchiolitis (DPB) and bronchiolar disease associated with rheumatoid arthritis. The present study assessed how these conditions could be differentiated. The subjects included 25 DPB patients and 15 RA patients with bronchiolar disease (RA-BD). Patients with either condition had chronic cough, purulent sputum, dyspnea and coarse crackles. Most patients with either DPB or RA-BD had a history of sinusitis as well as elevated cold hemagglutin titers and decreased levels in partial pressure of oxygen (PaO2), forced expiratory volume in one second (FEV1.0) and V 25/Ht. On histological examination, both conditions also shared various histological patterns although panbronchiolitis lesions were more common in DPB than RA-BD (68% vs 20%) and bronchiolar obliteration appeared to occur at more proximal sites in RA-BD than DPB. However, there were important differences: long-term treatment with erythromycin had less effect in RA-BD than DPB, and the frequency of HLA B54 tended to be higher in DPB than RA-BD (50.0% vs 22.2%), suggesting that they are distinct conditions.

Adult↗
PubMed1998

[Pulmonary cryptococcosis exhibiting diffuse multiple nodular shadows].

We report a case of pulmonary cryptococcosis showing diffuse multiple nodular shadows in all lung fields. A 39-year-old woman with no immunological abnormalities was admitted with complaints of cough and sputum. She had experienced measles 4 weeks prior to admission. Chest x-ray films revealed diffuse nodular opacities throughout the lung fields, a finding suggestive of metastatic lung cancer. Detailed examinations, including transbronchial lung biopsy, were not conclusive. A diagnosis of pulmonary cryptococcosis was made on the basis of findings from video-assisted thoracoscopic biopsy. Primary pulmonary cryptococcosis usually appears as a solitary nodule or limited infiltration. Immunologically compromised hosts commonly demonstrate various abnormal shadows, such as the multiple nodular shadows observed in our patient. It has been reported that measles infection can cause temporary immune suppression. Secondary immunodeficiency resulting from the preceding infection with measles could explain the unusual chest x-ray findings in this case.

Adult↗
PubMed1998

Changes in sympathetic and parasympathetic function in alcoholic neuropathy.

We examined sympathetic and parasympathetic function in 17 chronic alcoholics. The subjects were divided into 4 groups; (1) alcoholics without neurologic deficits, (2) alcoholics with mild neuropathy, (3) alcoholics with prominent neuropathy, (4) patients with alcoholic neuropathy but long abstinence. We measured pulsatile arterial pressure (AP) noninvasively and heart rate (HR) was calculated from the AP signals. The sweat response on the palm and sole were measured by ventilated capsular method, while the cutaneous blood flow response by laser Doppler flowmetry. The AP, HR, sweating and cutaneous blood flow response to the Valsalva maneuver were evaluated. In alcoholics with minimal and prominent neuropathy, a pressor (overshooting) in phase IV of the Valsalva maneuver were decreased significantly. The HR response (reflex bradycardia) in phase IV of the Valsalva maneuver was significantly decreased only in alcoholics with prominent neuropathy. The alcoholics with no or minimal neuropathy showed exaggerated sweat responses on the palm and sole. In prominent alcoholic neuropathy, the sweat response was greater on the palm, but diminished on the sole. In no or minimal neuropathy, magnitude of the blood flow response was markedly reduced on both sites. The low resting blood flow levels may contribute to the diminished response. We also evaluated pupillary light reflex and response to methacholine in 7 alcoholics with neuropathy by a portable infrared pupillometer system that can be used with personal computers. Maximum constriction velocity of the pupillary light reflex in patients with alcoholic neuropathy was slower than that in the controls. Reflex amplitude was smaller in the alcoholics than that in the control. However, local administration of methacholine did not change pupillary size and light reflex in the alcoholics same as the controls. The data suggest that preceding sympathetic hyperfunction related with distressed autonomic center is existing with sympathetic hypofunction involved from the sympathetic fibers, target organs and higher center.

Adult↗
PubMed1998

[Effect of pharmacist's instruction on the treatment of asthmatics with inhaled steroid].

Pharmacist's instruction is provided to asthmatic patients who received an inhaled steroid in Hamamatsu University Hospital. We studied influences of pharmacist's instruction on the repeutic effects of an inhaled steroid, beclomethasone dipropionate (BDP). In 29 patients who had been treated with inhaled BDP under the physician's instruction for more than 3 months, we examined drug compliance, correctness of inhalation procedure and treatment score, symptom score, peak expiratory flow (PEF) values, and compared these before and after the instruction. The instruction was repeatedly provided at an interval of about one month. Patients who followed the indicated regimen were 55.2 and 93.1% before and after the instruction, respectively. An appropriate inhalation maneuver was respectively. An appropriate inhalation maneuver was performed in 24.1 and 93.1% of patients before and after the instruction, respectively. PEF values increased by 12.9 +/- 9.3% (mean +/- standard deviation, p < 0.01) after the instruction. In conclusion, pharmacist's repeated instruction enhanced the therapeutic effects of inhaled BDP in patients with asthma.

Administration, Inhalation↗
PubMed1998

[Interstitial pneumonia preceding systemic sclerosis].

We describe a 57-year-old man with interstitial pneumonia associated with systemic sclerosis. About 3 years prior to the appearance of distinctive signs of systemic sclerosis, he was admitted to our hospital with a chronic dry cough. A chest roentgenogram on admission revealed reticulonodular shadows in both lung fields. There were no abnormal laboratory findings. Open lung biopsy specimens revealed patterns indicative of usual interstitial pneumonia, and myxomatous connective tissue within the lumen of the airways. Skin biopsy specimens showed heightened levels of collagen in the dermis, a finding consistent with systemic sclerosis. The patient was given a diagnosis of lung involvement preceding systemic sclerosis despite the absence of concurrent skin symptoms.

Cryptogenic Organizing Pneumonia↗
PubMed1997

Expression of tumor necrosis factor-alpha in muscles of polymyositis.

We immunohistochemically examined biopsied muscles from nine untreated patients with polymyositis (PM) and five patients with other neuromuscular diseases (ONMD), using monoclonal antibodies to tumor necrosis factor-alpha (TNF-alpha) and lymphoid surface markers. In muscles of three patients with PM, we observed many TNF-alpha positive macrophages and lymphocytes in endomysium and around vessels in the muscles. By contrast, there were few, weakly TNF-alpha stained cells in muscles of three patients with ONMD. The ratio of TNF-alpha-positive cells to the muscle fibers and the ratio of TNF-alpha-positive cells to the mononuclear cells were significantly higher in PM compared with ONMD. In addition, we observed atrophic muscle fibers more frequently in TNF-alpha-positive muscles than TNF-alpha-negative ones. We conclude that, at least, in a part of PM patients, TNF-alpha produced locally may contribute to the pathogenesis of PM.

Adult↗
PubMed1997

Epigallocatechin gallate-induced histamine release in patients with green tea-induced asthma.

BACKGROUND AND OBJECTIVE: Epigallocatechin gallate is the causative agent of green tea-induced asthma. To determine whether an IgE-mediated mechanism plays a pathogenetic role in this disorder, we measured histamine release after in vitro exposure to epigallocatechin gallate. METHODS: Subjects included eight patients (four men and four women) with green tea-induced asthma, who had been diagnosed by skin test and inhalation challenge, and eight controls (four asthmatic subjects with no previous exposure tea dust and four healthy volunteers). Heparinized whole blood samples were taken and incubated with epigallocatechin gallate at various concentrations (final concentration range, 0.003 to 300 micrograms/mL) for 30 minutes at 37 degrees C. After centrifugation, histamine was measured in the cell-free supernatants by radioimmunoassay. Histamine release was expressed as a percentage of total histamine. A result higher than 10% was considered positive. RESULTS: In one of the tea-sensitive patients, epigallocatechin gallate did not cause histamine release. Five of the other seven patients (71%) demonstrated a positive, dose-dependent histamine release to epigallocatechin gallate. In asthmatic and normal controls, histamine release was not observed at any epigallocatechin gallate concentration. Furthermore, a significant correlation was noted between the maximum percentage histamine release and the threshold epigallocatechin gallate concentration for intradermal skin testing. CONCLUSION: These results indicate that an IgE-mediated response is the basis for green tea-induced asthma.

Adult↗