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Biomedical subjects

K Shimada

Publications and source records attributed to K Shimada.

At least 271 records · Page 15Linked to original sources
PubMed2000

[Secondary cardiomyopathy accompanied by neuromuscular disorders].

There are many neuromuscular diseases associated with cardiomyopathy. Cardiac involvement with progressive muscular dystrophy (Duchenne and Becker type) and some type of limb-girdle muscular dystrophy were characterized by impaired left ventricular systolic function, such as dilated cardiomyopathy like status. In Friedreich ataxia various types of left ventricular hypertrophy were reported. While in myotonic dystrophy and Emery-Dreifuss muscular dystrophy, conduction disturbance and tachyarrhythmia are common types of cardiac manifestation. The severity of cardiac involvement in these diseases is not necessarily concordant with that of skeletal muscle. Recently the genes of these diseases were identified by linkage analysis. We review cardiac abnormalities of these diseases, especially relationship between severity of cardiac disorder and gene abnormalities.

Cardiomyopathies↗
PubMed2000

The mechanism responsible for the drowsiness caused by first generation H1 antagonists on the EEG pattern.

The present study was performed to clarify the mechanism responsible for the drowsiness caused by first generation H1 antagonists according to electroencephalogram activity. All H1 antagonists used in the present study caused the EEG-recorded drowsiness pattern, i.e., increases in EEG power spectra of the delta and theta bands at the frontal cortex in rats. The potency of cyproheptadine was greater than those of diphenhydramine and promethazine, while that of pyrilamine was less than those of the other drugs examined. The increase in EEG power spectra in the delta band induced by H1 antagonists was antagonized by pretreatment with both histidine and physostigmine. The effect of pyrilamine was more potently antagonized by histidine and less potently antagonized by physostigmine as compared to diphenhydramine, promethazine and cyproheptadine. The increases in EEG power spectra induced by H1 antagonists were neither antagonized nor potentiated by 5-hydroxytryptophan. These results clearly indicate that the increases in EEG power spectra in the delta and theta bands at the frontal cortex in rats induced by first generation H1 antagonists are responsible for both histaminergic and cholinergic mechanisms.

5-Hydroxytryptophan↗
PubMed2000

[Susceptibilities of bacteria isolated from patients with lower respiratory infectious diseases to antibiotics (1998)].

The bacteria isolated from the patients with lower respiratory tract infections were collected by institutions located throughout Japan, since 1981. Ikemoto et al. have been investigating susceptibilities of these isolates to various antibacterial agents and antibiotics, and analyzed some characteristics of the patients and isolates from them each year. Results obtained from these investigations are discussed. In these 18 institutions around the entire Japan, 532 strains of presumably etiological bacteria were isolated mainly from the sputa of 438 patients with lower respiratory tract infections during the period from October in 1998 to September in 1999. MICs of various antibacterial agents and antibiotics were determined against 85 strains of Staphylococcus aureus, 100 strains of Streptococcus pneumoniae, 96 strains of Haemophilus influenzae, 75 strains of Pseudomonas aeruginosa (non-mucoid strains), 6 strains of Pseudomonas aeruginosa (mucoid strains), 38 strains of Moraxella subgenus Branhamella catarrhalis, 26 strains of Klebsiella pneumoniae etc., and the susceptibilities of 517 strains were assessed except for those strains that died during transportation. S. aureus strains for which MICs of oxacillin (MPIPC) were higher than 4 micrograms/ml (methicillin-resistant S. aureus: MRSA) accounted for 60.0%. Vancomycin (VCM) and arbekacin (ABK) showed the most potent activities against MRSA. But one of MRSA showed resistance to ABK with the MIC of 64 micrograms/ml. The sensitive strains of MRSA to VCM have decreased. The frequency of penicillin (PC)-intermediate S. pneumoniae (PISP) + PC-resistant S. pneumoniae (PRSP) have increased in 46.0% for 1998 comparatively from 30.9% of 1997's. But PRSP decreased, and PISP increased into 39.0% of 1998 years from 19.8% of 1997's. Panipenem (PAPM), imipenem (IPM) and faropenem (FRPM) showed the most potent activities against S. pneumoniae with MIC80s of 0.125 microgram/ml or below. Against H. influenzae and M. (B.) catarrhalis, almost all the drugs showed good activities. The sensitive strains of them against ceftazidime (CAZ) decreased in 1997, but those have increased in 1998. Inversely, the susceptibility of them against cefotiam (CTM) had been higher in 1997, but those have been lower in 1998. Tobramycin (TOB) showed the most potent activity against P. aeruginosa (both mucoid and nonmucoid strains). All drugs except ampicillin (ABPC) were active against K. pneumoniae. A quite few of K. pneumoniae showed low susceptibilities. Also, we investigated year to year changes in the characteristics of patients, their respiratory infectious diseases, and the etiology. The examination of age distribution indicated that the proportion of patients with ages over 70 years was 48.6% of all the patients showing a slight increase in every year. About the proportion of diagnosed diseases as follows: Bacterial pneumonia was the most frequent with 40.2%. The ratio of it has increased slightly, and the increased rate was 10% in patients with ages over 70 years compared with the results in 1997. Chronic bronchitis have decreased slightly with 27.6% in 1998. Number of strains isolated from patients before administration of antibiotics were more than those after administration of them in chronic bronchitis, but these were almost same number in bacterial pneumonia. Administration of antibiotics has changed the results of the frequency of isolation of bacterial species. Bacterial isolations before administration of antibiotics were as follows: S. pneumoniae 26.7%, H. influenzae 23.8%, S. aureus 13.3% and M. (B.) catarrhalis 10.8%. The frequencies of S. aureus decreased after antibiotics administration over 15 days, but the frequencies of P. aeruginosa (both mucoid and non-mucoid) was not affected. The frequencies of P. aeruginosa was 45.5% after administration over 15 days. The frequencies of S. pneumoniae decreased upon administration of antibiotics, these were only 4.5% over 15 days. The frequencies of H. (

Anti-Bacterial Agents↗
PubMed2000

[Management strategy for patients with coronary artery disease associated with valve disease].

BACKGROUND: The indication of combined operation of coronary artery bypass (CAB) and valve surgery is controversial. METHODS: Between April 1992 and January 2000, 13 patients underwent a combined operation with CAB and valve replacement, and 4 patients (2 were overlapped) who had had a previous CAB underwent a reoperative valve replacement. RESULTS: One patient who underwent AVR and reCAB 11 years after the initial CAB died. Another patient with preoperative MRSA pneumonia and received MVR and CAB died 4 months after surgery with MRSA sepsis. However, others showed an excellent post-operative course. The causes of necessitating the reoperation were: unawareness of aortic stenosis at the initial emergency CAB in 1 patient, progression of aortic stenosis in 1 patient, progression of aortic regurgitation in 1 patient, and progression of mitral regurgitation in 1 patient. CONCLUSION: The results of the combined CAB and valve replacement operation were acceptable. Patients with mild-moderate valve disease should be considered as candidates for valve surgery at the time of CAB.

Aged↗
PubMed2000

[A case of mediastinal pseudocyst with unusual cystic findings in computed tomography].

We report here a case of mediastinal pseudocyst with unusual CT findings. A 25-year-old woman was admitted to our hospital due to a chest abnormal shadow. She had a cystic mass which was located at anterior mediastinum and was adjacent to great vessels broadly without invasive findings. The intraoperative and histological findings revealed that the cystic mass was a pseudocyst which had been generated by the rupture of a thymic cyst to the mediastinum.

Adult↗
PubMed2000

[A case report of a successful surgical treatment for infective endocarditis involving four valves in a elderly patient with ventricular septal defects].

A 72-year-old female was examined because of acute congestive heart failure. Echocardiogram revealed vegetations on aortic and pulmonary valve, regurgitation of four valves, and perimembraneous ventricular septal defect. Aortic valve replacement, mitral valve replacement, repair of tricuspid valve using a Carpentier ring, partial resection of pulmonary valve, and direct closure of VSD was performed. Pathological finding of resected valves showed acute endocarditis. A patient resumed social activities after surgery.

Aged↗
PubMed2000

[Successful treatment for descending necrotizing mediastinitis: a case report].

A 21-year-old female was admitted to our hospital because of high fever, neck swelling, and dyspnea. She was diagnosed as descending necrotizing mediastinitis (DNM) extended from odontogenic infection. On the day of admission, she underwent cervical drainage. Next day, the CT scan showed an abscess below the tracheal bifurcation and bilateral pleural effusion. Mediastinal drainage was performed through a right thoracotomy, and a left thoracic tube was inserted. Anaerobic Peptostreptococcus was found with bacteriological culture. After the mediastinal drainage, bilateral thoracic irrigation was performed through the thoracic tubes. Left thoracic tube was removed on the 8th day and right one was removed on the 20th day after the thoracotomy. She was discharged on the 42nd day. DNM is relatively rare, but it is lethal disease with high mortality. Immediate and sufficient mediastinal drainage is indispensable for the disease.

Abscess↗
PubMed2000

[Present condition of lung transplantation candidates in eastern Japan].

We investigated the present condition of lung transplant candidates and the familiarity of doctors in eastern Japan by questionnaire. We shipped questionnaires to 614 hospitals in the Hokkaido district, the Tohoku district, the Kanto district and Niigata Prefecture, a received responses from 216 departments (200 hospitals). The percentage of respondents was 32.6%. There were 191 lung transplant candidates, 97 men and 94 women, in the past two years. Moreover, there were 45 patients with primary pulmonary hypertension (PPH), 38 with idiopathic pulmonary fibrosis, 23 with pulmonary emphysema, 20 with pulmonary lymphangiomyomatosis, among others. Currently, however, there are 88 patients who are lung transplant candidates, a large number, in eastern Japan. On the other hand, only 38 of 68 departments had informed their patients about lung transplantation. It was a lamentable result for transplant surgeons, and points urgently to the importance of giving information about lung transplantation.

Adolescent↗
PubMed2000

[Prenatal diagnosis of urological abnormalities].

The frequent discovery of fetal congenital abnormalities has led to a better understanding of pediatric urological disorders. On the other hand, new questions on clinical examinations and management of the children have given rise to much controversy. We reviewed the difficulties and pitfalls surrounding the urological prenatal diagnosis. Accuracy of ultrasonography is operator-dependent, and main factors leading misdiagnosis include oligohydramnios and rare incidence of the abnormalities. Underlying disorders of prenatal hydronephrosis are multifactorial. Efforts to obtain co-existing findings, such as ureteral dilatation or bladder abnormalities, are essential to make accurate diagnosis. Evaluation of fetal renal function is mandatory in critical cases with decreased amniotic fluid volume. Biochemical analysis of fetal urine may be most reliable in differentiating fetuses with a good prognosis from those with a poor prognosis.

Female↗
PubMed2000

[Clinical analysis of patients referred for lung transplantation in eastern Japan].

We investigated the indications for lung transplantation (LTx) in Japan and discussed questions regarding the current Japanese criteria of LTx. This study examined 37 patients referred to our institute for LTx. Among these patients, there were 11 cases of primary pulmonary hypertension (PPH), 6 of lymphoangiomyomatosis (LAM), 4 of Eisenmenger's syndrome, 3 of bronchiolitis obliterans, 2 each of bronchiectasis, idiopathic pulmonary fibrosis (IPF), and pneumoconiosis, and 7 of other diseases. The most frequent age group was 30-39 years (12 cases, 32.4%), and more than half of the patients were female (22 cases, 59.5%). The regions of residence of the patients were Tohoku (19 patients), Kanto (16), and Chubu (2). Patients were referred from all over eastern Japan. On evaluation, LTx was contraindicated in 5 cases, in 4 of which mechanical ventilation had been installed before consultation with us. Six patients died before registration on the Japan Organ Transplant Network (JOT). 6 transplant candidates were registered with JOT, but one (PPH) died after 6 months of waiting, and one (LAM) received a lung transplant from a brain dead cadaver donor. We propose to reform and clarify the Japanese criteria for LTx-both indications and contraindications, to include such indications as a survival probability of less than two years, and such contraindications as mechanical ventilation. Early consultation at LTx centers was hoped for, in accordance with the International Guidelines and a transplant window.

Adolescent↗
PubMed1999

Immunocytochemical localization of serotonin and serotonin transporter (SET) in taste buds of rat.

We used an immunocytochemical approach to study the localization of serotonin and its termination system, serotonin transporter (SET), in the taste buds of rats using specific antibodies against serotonin and SET. Under confocal laser scanning microscopy, both serotonin and SET immunoreactivity were detected in the taste buds of rat vallate papillae. Serotonin immunoreactivity was seen in the spindle-shaped cells with apical processes that seemed to be light (Type II) taste cells. SET-immunoreactivity was mainly localized in the periphery or interfaces between the taste cells. Double staining studies revealed that all serotonin-containing taste cells were immunoreactive for SET, while a subclass of SET-positive cells showed serotonin immunoreactivity. These data support the hypothesis that serotonin plays a transmitter role in taste receptor cells and suggest that the serotonin-induced sensation of taste is terminated by serotonin uptake through serotonin transporter.

Animals↗
PubMed1999

Comparison of the binding sites for high-potential iron-sulfur protein and cytochrome c on the tetraheme cytochrome subunit bound to the bacterial photosynthetic reaction center.

A tetraheme cytochrome subunit bound to the photosynthetic reaction center (RC) of purple bacterium, Rubrivivax gelatinosus, interacts with two types of soluble electron donors, cytochromes c and high-potential iron-sulfur protein (HiPIP), at a binding domain in the vicinity of low-potential heme 1, the fourth heme from the special pair of bacteriochlorophyll. To clarify the mechanism of the interaction, the domain around heme 1 was examined using site-directed mutants that changed the surface charge in the region within 20 A from the heme edge. In the case of the interaction with soluble cytochrome c, a strong dependence on the sign of the introduced charge was observed in all mutants: positive charge inhibited the reaction rate, whereas additional negative charge accelerated it. This confirmed the electrostatic nature of the binding. Interaction with HiPIP was inhibited by a limited number of mutations at the close vicinity of heme 1, and no acceleration was observed (the effects of some mutations were independent of the sign of the introduced charge). The acidic residues which were critically important for the binding of cytochrome c showed much less contribution to the binding of HiPIP. The binding site for HiPIP appears to be mostly formed by uncharged and hydrophobic residues, occupying a significantly smaller area than the cytochrome-c-binding site. It is proposed that the docking of HiPIP to the RC in Rvi. gelatinosus is primarily controlled by hydrophobic contacts between protein surfaces, thus differing from the electrostatic mode of the RC-cytochrome c interaction.

Bacterial Proteins↗