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Biomedical subjects

K Hamada

Publications and source records attributed to K Hamada.

At least 91 records · Page 5Linked to original sources
PubMed2000

Clinical use of capillary PCR to diagnose Mycoplasma pneumonia.

In the present study, serologic data were compared with data obtained by capillary PCR to establish the efficacy of capillary PCR for the determination of Mycoplasma infection in samples obtained from throat swabs, bronchoalveolar lavage fluids (BALF), and sputum of patients with Mycoplasma pneumonia. We performed PCR analysis for Mycoplasma DNA on a total of 325 samples from 197 patients with community-acquired pneumonia and in whom Mycoplasma pneumonia was suspected. There were 68 PCR-positive specimens. Review of the differences in PCR positivity rates based on the site of specimen collection showed the highest rate of detection (28.6%) from throat swabs. From among the 31 patients with significantly elevated titers of serum Mycoplasma antibodies, the PCR results were positive for 25 patients. Thus, capillary PCR had a sensitivity of 80.6% (25 of 31). Five of the six false-negative results were from throat swab specimens. Moreover, testing (PCR) had been performed only once for these five patients with false-negative results. From among the PCR-positive findings from BALF specimens, there were no false-positive results. BALF specimens were very useful, except for the technical procedures and increased patient burden required to obtain these specimens. We suggest that the use of throat swab specimens in capillary PCR is much more suitable for diagnosing Mycoplasma pneumonia in routine clinical practice; however, careful throat swab specimen collection and an increase in the number of times that the PCR is performed are necessary to reduce the rate of false-negative results.

Bronchoalveolar Lavage Fluid↗
PubMed2000

Airflow limitation in Japanese smokers: significance of serum neutrophil elastase/alpha(1)-proteinase inhibitor ratio and FEV(1) (%pred) adjusted by pack-years.

BACKGROUND: In spite of the known role of cigarette smoking in the development of airflow limitation (AL), fewer than 20% of smokers actually develop chronic obstructive pulmonary disease (COPD). OBJECTIVES: We examined how smoking histories and indices in blood are related to the degree of AL in asymptomatic smokers in order to determine whether they can predict the development of AL. METHODS: Spirometry and peripheral blood tests were examined in 433 Japanese asymptomatic current smokers at the initial examination. Forced expiratory volume in 1 s (FEV(1)) was measured periodically for 2 or more years (2-13 years) in 66 of the subjects. RESULTS: AL defined as an FEV(1)/vital capacity of less than 0.7, was found in 11.3% (49 of 433) of the smokers. Pack-years of smoking, serum amounts of alpha(1)-proteinase inhibitor, and serum procollagen III peptide activities were correlated with the degree of AL. Fifteen percent (10 of 66) of subjects underwent rapid declines in FEV(1) that were found to be related not with smoking amounts or initial FEV(1), but with low FEV(1) (%pred) adjusted by pack-years and an elevated serum neutrophil elastase/alpha(1)-proteinase inhibitor ratio. These results suggest that smokers with a low FEV(1) out of proportion to pack-years are susceptible smokers at a high risk of developing COPD, and further, that increased proteinase burden relative to antiproteinase activity may contribute to the development of COPD. CONCLUSIONS: We conclude that the serum neutrophil elastase/alpha(1)-proteinase inhibitor ratio and FEV(1) (%pred) adjusted by pack-years can be reliable predictors of the development of COPD.

Adult↗
PubMed2000

Significance of the interleukin-1 receptor antagonist/interleukin-1 beta ratio as a prognostic factor in patients with pulmonary sarcoidosis.

BACKGROUND: Various factors such as serum angiotensin-converting enzyme (sACE) activity, bronchoalveolar lavage (BAL) fluid lymphocyte percent, CD4/CD8 ratio, and shadows on chest radiograph have been identified as indexes of disease activity in patients with sarcoidosis. However, it remains to be confirmed whether these factors can predict clinical outcomes. OBJECTIVE: To examine whether the interleukin-1 receptor antagonist (IL-1ra)/IL-1 beta ratio can predict the clinical course, we prospectively followed the clinical courses of 30 patients with pulmonary sarcoidosis 4 years after measurement of immunoreactive amounts of IL-1ra or IL-1 beta in the culture supernatants obtained from BAL fluid macrophages. METHODS: Immunoreactive amounts of IL-1ra or IL-1 beta were measured using ELISA. Changes in pulmonary function, sACE activity, and shadows on chest radiographs during observation periods were evaluated as markers of changes in disease activity. RESULTS: We found that the patients whose shadows on chest radiographs showed improvement had a higher molar IL-1ra/IL-1 beta ratio than the patients whose shadows persistently remained 4 years after BAL examination (p < 0.05). The molar ratio was found to be positively correlated with improvement of percent vital capacity (p < 0.05) and negatively correlated with the ratio of sACE activity at the time of the last observation to sACE activity at the time of BAL (sACE(LAST)/sACE(BAL), p < 0.01). The sACE(LAST)/sACE(BAL) ratio was significantly lower in patients whose shadows on chest radiographs decreased than in those whose shadows remained unchanged (p < 0.005). CONCLUSION: The IL-1ra/IL-1 beta ratio in the BAL fluid macrophage culture supernatants in patients with pulmonary sarcoidosis could be a useful marker in predicting the persistence of granulomatous lesions (chronicity).

Adult↗
PubMed2000

The hair follicle: a paradoxical androgen target organ.

Androgens are the main regulator of normal human hair growth. After puberty, they promote transformation of vellus follicles, producing tiny, unpigmented hairs, to terminal ones, forming larger pigmented hairs, in many areas, e.g. the axilla. However, they have no apparent effect on the eyelashes, but can cause the opposite transformation on the scalp leading to the replacement of terminal hairs by vellus ones and the gradual onset of androgenetic alopecia. This paradox appears to be an unique hormonal effect. Hair follicles are mainly epithelial tissues, continuous with the epidermis, which project into the dermis. A mesenchyme-derived dermal papilla enclosed within the hair bulb at the base controls many aspects of follicle function. In the current hypothesis for androgen regulation, the dermal papilla is also considered the main site of androgen action with androgens from the blood binding to receptors in dermal papilla cells of androgen-sensitive follicles and causing an alteration of their production of paracrine factors for target cells e.g. keratinocytes. Studies of cultured dermal papilla cells from sites with different responses to androgens in vivo have confirmed the paradoxical responses. All dermal papilla cells from androgen-sensitive sites contain low capacity, high affinity androgen receptors. However, only some cells formed 5alpha-dihydrotestosterone, e.g. beard but not axillary cells, in line with hair growth in 5alpha-reductase deficiency. Incubation with androgens also stimulated the mitogenic capacity of beard cell media, but inhibited that produced by scalp cells. This suggests that the paradoxical differences are due to differential gene expression within hair follicles, presumably caused during embryogenesis.

Androgens↗
PubMed2000

Resistance of very young mice to inhaled allergen sensitization is overcome by coexposure to an air-pollutant aerosol.

The role of air pollution in the initiation of asthma is controversial. We sought to model the potential effects of air pollution on immune responses to inhaled allergens in developing lungs by using very young mice. Neonatal mice were repeatedly exposed to aerosolized ovalbumin (OVA; 3% in phosphate-buffered saline for 10 min/d, from Days 5 to 15 of age). Some mice were also exposed to leachate of residual oil fly ash (ROFA-s), a surrogate for ambient air particles, for 30 min, on Days 6, 8, and 10 of age). Repeated exposure of very young mice to allergen alone (OVA) or pollutant alone (ROFA-s) had no effect on airway hyperresponsiveness (AHR, measured as enhanced pause (Penh) with noninvasive plethysmography at Day 16 of age), and did not cause inflammation or OVA-specific antibody production. Similar exposures of adult mice to either OVA alone or to OVA + ROFA-s did result in AHR, without evidence of enhancement by combined exposure. In contrast, very young mice exposed to both OVA and ROFA-s showed significantly increased AHR (e.g., Penh with 50 mg/ml methacholine for OVA + ROFA-s versus OVA alone = 2.6 +/- 0.4 [mean +/- SE], versus 1.2 +/- 0.1; p < 0.01, n >/= 15), and produced OVA-specific IgE and IgG upon allergen challenge a week later. Immunostaining of airways taken from mice at Day 11 showed a marked increase in Ia(+) cells after OVA + ROFA-s exposure. We conclude that exposure to pollutant aerosols can disrupt normal resistance to sensitization to inhaled allergens, and can thereby promote development of airway hypersensitivity in this neonatal/juvenile mouse model.

Administration, Inhalation↗
PubMed2000

A case of progressive systemic sclerosis complicated by massive pleural effusion with elevated CA125.

A tumor marker, CA125, is known to increase in the serum or other body fluids in various malignancies such as ovarian cancer. Here we present a case of progressive systemic sclerosis (PSS) with massive pleural effusion, in which CA125 in the serum and pleural fluid were elevated. The serum level of CA125 decreased in accordance with the change of the pleural effusion. CA125 level may be an indicator for the activity of serositis in some cases with collagen vascular diseases.

CA-125 Antigen↗
PubMed2000

A case of adult-onset Still's disease complicated by non-Hodgkin's lymphoma.

Left cervical lymphadenopathy developed in a 50-year-old male who had a history of adult-onset Still's disease for the preceding 18 months. Still's disease is characterized by rash, fever, and leukocytosis. Lymphadenopathy has been reported in about 60% of the patients, and most histopathologic studies have shown non-specific reactive hyperplasia. However, in this case, an open biopsy of the cervical node revealed a histology of diffuse large B-cell lymphoma. The B-cell malignant lymphoma that developed may have resulted from a sequential progression of a previous stage of benign lymphoproliferative lesion. Our case suggests that the pathophysiology of adult-onset Still's disease involves the stimulation of lymphoid systems to the point of progression towards lymphoma. Malignant lymphoma should be added to the list of life-threatening complications which, although rare, are associated with this disease.

Humans↗
PubMed2000

Traumatic basal subarachnoid hemorrhage due to rupture of the posterior inferior cerebellar artery--case report.

A 20-year-old male presented with traumatic basal subarachnoid hemorrhage after being involved in a fight. Antemortem clinical examinations could not exclude the possibility of rupture of abnormal blood vessels because of the absence of external injuries. Careful postmortem examination of the head and neck regions and histological examination of the intracranial arteries demonstrated traumatic rupture of the left posterior inferior cerebellar artery due to a fist blow to the jaw. This case indicates the need for careful autopsy examination for the differentiation of traumatic and non-traumatic basal subarachnoid hemorrhages.

Adult↗
PubMed2000

Two regions of homozygous deletion clusters at chromosome band 9p21 in human lung cancer.

We examined 149 lung cancer cell lines for homozygous deletions using 24 DNA markers, which were mapped and ordered in chromosome band 9p21, to define the target regions for 9p21 deletions in human lung cancer. Homozygous deletions were detected in 39 (26%) cell lines and clustered at 2 independent regions. One was the region containing the p16/CDKN2A tumor suppressor gene, and this region was deleted in 32 (21%) cell lines. The other was the region containing D9S171, which is the locus approximately 3 Mb proximal to the CDKN2A locus. This region, designated as the D9S171 region, was deleted in 18 (12%) cell lines. Seven of the 18 cell lines had identical minimum deletions of a 17,036 bp sequence located 20 kb distal to the D9S171 locus. However, such a deletion was also observed in the corresponding B-lymphoblastoid cell line from 1 of the 7 cell lines and in 5 (16%) of 32 noncancerous tissues, suggesting that the deletion was a genetic polymorphism. By considering this polymorphism, 11 (7%) cell lines still had deletions at the D9S171 region. Two NSCLC cell lines showed deletions at the D9S171 region and retentions of the CDKN2A locus. Furthermore, an NSCLC cell line showed discontinuous deletions including either the CDKN2A or D9S171 locus. Therefore, the region surrounding the D9S171 locus was defined as another target region for the 9p21 deletions. It is possible that unknown tumor suppressor gene(s) are present in this chromosomal region. Genes Chromosomes Cancer 27:308-318, 2000.

Carcinoma, Non-Small-Cell Lung↗
PubMed2000

Adenoviral expression of p53 represses telomerase activity through down-regulation of human telomerase reverse transcriptase transcription.

Telomerase activation is a critical step in cellular immortality and oncogenesis. The activity of telomerase is known to be correlated with cell proliferation, but its regulation by cell cycle regulators is not well understood. In the present study, we examined the effects of p53 on telomerase activity. Wild-type p53 was introduced into SiHa cells via a recombinant adenoviral vector, Ad5CMV-p53, and change in telomerase activity was examined by quantitative telomerase assay. Telomerase activity in the Ad5CMV-p53-infected cells was significantly repressed 36 h after infection following down-regulation of human telomerase catalytic subunit [human telomerase reverse transcriptase (hTERT)] mRNA expression, whereas no change in telomerase activity was observed in the cells infected with control vector AdSCMV-beta-gal. Interestingly, repression of telomerase activity was an early event that preceded cell growth inhibition or apoptosis induced by p53 overexpression, suggesting that p53 directly regulates telomerase activity. Transient expression assays using hTERT-promoter reporter constructs revealed that overexpression of p53 significantly repressed promoter activity of hTERT. 5'-Truncation of the promoter sequences revealed that the proximal core promoter region containing multiple binding sites for transcription factor Spl was responsible for p53-mediated transcriptional repression. Mutations in these binding sites for Spl led to failure of p53 to repress transcription. These findings suggest that p53 repressed telomerase activity through down-regulation of hTERT transcription and that interaction of p53 with Sp1 or other transcription factors may be involved in this regulation.

Adenoviridae↗
PubMed2000

[Aircraft crashes in sky sports. Report of two autopsy cases and review of the accidents during 1981 to 1997 in Japan].

The authors report two forensic autopsy cases of pilots who died in glider and ultra-light plane crashes in Aso, Kumamoto and review sky sports accidents in Japan (1981-1997). In the glider crash, sharp abdominal pain due to gallstones in a 78-year-old pilot was a possible cause of the accident. In the ultra-light plane crash, unskillful control of the plane by a 38-year-old pilot was the cause of the accident. The incidence of sky sports accidents increased from 12 cases in 1981 to 62 cases in 1997. The mortality rate of the victims of the accidents is very high. Investigation of natural diseases in pilots as a cause of accidents and the mechanisms of fatal injuries will help to assess preventive measures against sky sports accidents.

Accidents, Aviation↗
PubMed2000

Perforation of rotator cuff increases interleukin 1beta production in the synovium of glenohumeral joint in rotator cuff diseases.

OBJECTIVE: To study the hypothesis that perforation of the rotator cuff increases the degree of inflammation in the synovium of the glenohumeral joint in rotator cuff diseases. METHODS: Thirty-five synovial specimens in the glenohumeral joint of patients with rotator cuff diseases were examined. They were obtained during surgery and divided into 2 groups on the basis of the presence or absence of rotator cuff perforation, i.e., perforating and nonperforating tears. The expression levels of inflammatory cytokine mRNA of interleukin 1beta (IL-1beta) and 2 forms (secreted type and intracellular type) of IL-1 receptor antagonist (IL-1ra) were measured by reverse transcriptase polymerase chain reaction (RT-PCR). The protein level of IL-1beta was determined by Western blot analysis. IL-1beta producing cells were also identified by in situ RT-PCR and immunohistochemistry. RESULTS: In perforating tears cytokine mRNA in the glenohumeral synovium was more significantly expressed than in nonperforating tears. Also, higher levels of IL-1beta protein were detected in perforating tears. CONCLUSION: Perforation of the rotator cuff increases IL-1beta production in the glenohumeral joint, enhancing inflammatory intensity at the site. These findings suggest the possibility that glenohumeral synovitis in rotator cuff diseases may be a factor for the development of glenohumeral arthropathy.

Adult↗
PubMed2000

[Concentration of isepamicin sulfate in bone marrow blood].

Fifteen patients who were performed a rotator cuff repair were subjected for the determination of a concentration of isepamicin sulfate (ISP), which was infused intravenously, in venous blood and bone marrow blood. The concentrations were measured at 0, 30, 60 minutes after the injection. There was no statistically significance between ISP concentrations in venous and bone marrow blood. This study revealed that the transference of ISP to the bone marrow was excellent.

Adult↗