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Biomedical subjects

J Honda

Publications and source records attributed to J Honda.

At least 55 records · Page 3Linked to original sources

Atrial natriuretic peptide (ANP)-granules of auricular cardiocytes in dehydrated and rehydrated mice.

Atrial natriuretic peptide (ANP)-granules of auricular cardiocytes were examined by immunohistochemistry, transmission electron microscopy and ultrastructural morphometry in dehydrated and rehydrated mice. In addition, plasma ANP and tissue ANP mRNA levels were determined by radioimmunoassay and polymerase chain reaction, respectively. ANP immunoreactivity and the number of granules in the cardiocytes were increased with time in the dehydration group, while plasma ANP and tissue ANP mRNA levels were decreased on day 3 of dehydration. On day 3 of dehydration, the number of ANP-granules (153.2 +/- 8.3, mean +/- standard error) was significantly (p < 0.05) greater than in the control (125.8 +/- 6.7). IN the rehydration group, the immunoreactivity and number of ANP-granules were less than those in the group on day 3 of dehydration. The plasma ANP level during rehydration for 12 hr was slightly elevated in comparison with the group on day 3 of dehydration. The tissue ANP mRNA level after 12 hr of rehydration was lower than that on day 3 of dehydration. The diameter of ANP-granules was significantly (p < 0.01) smaller in all experimental groups than in the control. These findings suggest that synthesis and secretion of ANP are inhibited and ANP-granules are stored in auricular cardiocytes during dehydration.

Animals↗

Increased incidence of beta-lactamase-plasmid negative, high level methicillin-resistant Staphylococcus aureus (MRSA).

Recently isolated strains of methicillin-resistant Staphylococcus aureus (MRSA) have high levels of resistance to the agent and produce beta-lactamase less frequently than methicillin-susceptible strains (MSSA). This phenomenon has been observed in Japan. The majority of MSSA strains (26 of 30) isolated in 1992 produced beta-lactamase while only 18 of 31 and 25 of 67 MRSA strains, isolated in 1991 and in 1992 respectively, produced the enzyme. We analyzed the beta-lactamase gene (blaZ) in 30 strains each of MRSA and MSSA isolated from our hospital using the polymerase chain reaction. We found that 28 MSSA strains but only 14 MRSA strains possessed the gene. In addition, the present study indicates that many recently isolated MRSA strains, which lacked blaZ gene and were negative for beta-lactamase, consistently produced coagulase of type II (coagulase typing is a marker of epidemiology for Staphylococcus aureus). These beta-lactamase negative, type II coagulase producing and highly methicillin-resistant MRSA strains are considered to have an increased ability to successfully colonize individuals and an increased epidemic potential, probably because of the saving of the energy otherwise expended in beta-lactamase production and of the loss of beta-lactamase plasmid coding the mecA gene repressor, resulting in constitutive PBP2' production. These factors may contribute to the wide spread of these strains of MRSA in a nosocomial environment.

Humans↗

[Clinical significance of soluble interleukin-2 receptor levels in the cerebrospinal fluid in patients with adult T-cell leukemia complicated with meningeal infiltration].

We measured soluble interleukin-2 receptor (sIL-2R) levels in the cerebrospinal fluid (CSF) of patients with hematological malignancies especially, adult T-cell leukemia (ATL) and non-Hodgkin's lymphoma (NHL) with or without meningeal infiltration. CSF levels of sIL-2R were significantly higher in patients with ATL and NHL with meningeal infiltration than in patients with both diseases without meningeal infiltration. The sIL-2R levels in CSF were elevated in 4/4 ATL patients (100%) and 3/13 NHL patients (23%) with meningeal infiltration. CSF levels of sIL-2R from ATL patients with meningeal infiltration had a tendency to elevate in correlation with numbers of mononuclear cells and lactic dehydrogenase (LDH) in CSF. However, these had no correlation with serum levels of sIL-2R. Therefore, sIL-2 levels in CSF may be useful in the diagnosis of meningeal infiltration in patients with ATL, are probably specific markers for meningeal infiltration of ATL.

Adolescent↗

[Soluble interleukin-2 receptor and macrophage colony-stimulating factor (M-CSF) in cerebrospinal fluid in patients with hematological malignancies: clinical significance in adult T-cell leukemia with meningeal infiltration].

We measured soluble interleukin-2 receptor (sIL-2R) and macrophage colony-stimulating factor (M-CSF) levels in the cerebrospinal fluid (CSF) of patients with hematological malignancies with or without meningeal infiltration and meningitis. Levels of sIL-2R and M-CSF in the CSF of adult T-cell leukemia (ATL) patients with meningeal infiltration were significantly higher than those of ATL patients without meningeal infiltration and non-ATL patients with meningeal infiltration. There was a significant positive correlation between sIL-2R levels and numbers of mononuclear cells in CSF of ATL patients with meningeal infiltration. However, M-CSF levels did not correlate with numbers of mononuclear cells. There was no correlation between CSF and serum levels of sIL-2R. There was also no correlation between sIL-2R and M-CSF in the CSF. Therefore, sIL-2R and M-CSF levels in the CSF may be useful in the diagnosis of meningeal infiltration in patients with ATL. In particular sIL-2R may be a sensitive marker.

Biomarkers, Tumor↗

[Anemia due to chronic lead poisoning].

We report a case of anemia due to chronic lead poisoning. A 46-year-old female was admitted to our hospital because of general fatigue and anemia. A peripheral blood smear showed basophilic stippling. There was basophilic stippling and nuclear dysplasia of erythroblasts in the bone marrow. Laboratory findings were as follows: RBC 296 X 10(4)/microliter, Hb 8.5 g/dl, blood lead concentration 67 micrograms/dl, urinary lead concentration 309 micrograms/l, blood delta-ALA dehydrase 0.03 mumol/ml, urinary delta-ALA 25.2 mg/l, urinary coproporphyrin 8,810 micrograms/g.Cr, and blood protoporphyrin 612 micrograms/dl. Chronic lead poisoning was diagnosed and she was treated with Ca-EDTA.

Anemia↗

Photosensitive nitrile hydratase intrinsically possesses nitric oxide bound to the non-heme iron center: evidence by Fourier transform infrared spectroscopy.

Nitrile hydratase (NHase) from Rhodococcus sp. N-771 is a photosensitive enzyme that catalyzes hydration of nitriles to the corresponding amides. Light-induced Fourier transform infrared difference spectra between the inactive and active forms of NHase were measured with both the natural (14N) and 15N-labeled NHases. The results showed, for the first time, that NHase intrinsically possesses nitric oxide (NO) molecules bound to the non-heme iron center. The possible role of NO in the photoactivation process of NHase is discussed.

Enzyme Activation↗

Spectroscopic observation of the intramolecular electron transfer in the photoactivation processes of nitrile hydratase.

The photoactivation phenomena of the photosensitive enzyme nitrile hydratase (NHase) was studied by various spectroscopic methods. We have already shown that the photoactivation of NHase accompanies oxidation of an iron atom in the NHase [Honda et al. (1992) FEBS Lett. 301, 177-180]. From the results obtained in the present study by absorption, action, and fluorescence spectra, we show that the chromophore responsible for the photoactivation process is the iron complex, and the tryptophan residues in NHase induce the oxidation of the iron atom via an energy-transfer process. The nanosecond flash photolysis experiment revealed that this photoactivation process is completed within 50 ns, which suggests that the changes observable in the absorption spectra originate from an intramolecular electron transfer occurring from an electronically excited state. Also the role of a stabilizing reagent, namely, n-butyric acid (BA), was investigated using the above methods, which revealed that BA, besides its stabilizing effect, contributes to the increase in apparent photoactivation rate.

Butyrates↗

Rapid and sensitive diagnosis of cytomegalovirus and Pneumocystis carinii pneumonia in patients with haematological neoplasia by using capillary polymerase chain reaction.

We attempted the simultaneous detection of cytomegalovirus DNA (CMV-DNA) and Pneumocystis carinii (carinii-DNA) in sputum samples obtained from 20 patients with haematological neoplasm with pneumonia, using rapid cycle DNA amplification (capillary PCR). We used a thermal cycler for capillary PCR which featured recirculation of hot air for rapid temperature control of 10 microliters reaction samples in thin glass capillary tubes. We extracted DNA from patients' sputa using a simple method. A comparison of the results obtained using the phenol extraction-ethanol precipitation method and those obtained using our simple method was made, and demonstrated complete agreement between the two. For detection of CMV-DNA and P. carinii-DNA with capillary PCR it was not necessary to vary temperature setting based on the primers used. Therefore, capillary PCR was used for the simultaneous detection of CMV and P. carinii. After amplification, the total time required for which was 20 min, amplified products were electrophoresed on agarose gels and visualized with ethidium bromide. Product sensitivity was higher with capillary PCR than with conventional PCR. We conclude that capillary PCR amplification is a valuable tool for rapid and simple diagnosis of CMV and P. carinii pneumonias.

Adult↗

[Mechanism of efficacy of erythromycin on diffuse panbronchiolitis--effect of erythromycin on cytokine mRNA expression in human whole blood model].

Recently, "low-dose and long-term" erythromycin (EM) has been reported to be effective in treatment of diffuse panbronchiolitis (DPB), but its mechanism is still obscure. We studied the effect of EM on cytokine mRNA expression by using LPS-stimulated human whole blood as an experimental vivo model. IL-8 mRNA was expressed in biphasic fashion with peak expression at 6 hours and 20 hours from the start of LPS stimulation. When whole blood was pretreated with EM (2 micrograms/ml) for 1 hours. IL-8 mRNA expression was depressed at 20 hours (p < 0.025) from the start of LPS (1 microgram/ml) stimulation. However, when pretreated for 12 hours, it was not depressed. EM (2 micrograms/ml) also depressed IL-1 beta (p < 0.025) and TNF alpha (p < 0.05) mRNA expressions at 6 hours from the start of LPS stimulation. From the above results, it was suggested that the direct inhibition of IL-1 beta and TNF alpha production by EM resulted in subsequent depression of production of IL-8 that is a potent chemotactic factor for neutrophil, and consequently, EM acts to protect the bronchiole tissues of DPB patients from destruction by proteolytic enzymes released from neutrophils. This assumption seems to be supported by our previous observation that when patients with DPB were treated with EM a marked decrease in number of neutrophil in bronchoalveolar lavage fluid (BALF) was accompanied by clinical and radiographic improvement.

Adult↗

[Antibiotics susceptibilities and other biological properties of methicillin-resistant Staphylococcus aureus: observation in the last 2 years in our university hospital].

We examined biological properties of strains of methicillin-resistant Staphylococcus aureus (MRSA) which were isolated in our ward in 1991 and 1992. A total of 47 MRSA strains were isolated in 1991 and 64 in 1992. The majority of these strains of MRSA were highly resistant to DMPPC, CEZ and IPM, and were intermediately resistant to MINO. All these strains were, however, sensitive to VCM. The number of coagulase type II strains increased from 22 (46.8%) to 51 (79.7%), and that of enterotoxin type A strains from 27 (57.4%) in 1991 to 47 (73.4%) in 1992. The number of strains which produce Toxic Shock Syndrome Toxin-1 (TSST-1) also increased from 19 (40.4%) to 45 (70.3%), and those strains that produce beta-lactamase decreased from 24 (51.1%) to 21 (32.8%). From the above results, we confirmed the recent change in types of the epidemic strains of MRSA. Namely, there was a marked increase in number of strains which produce type II coagulase type A enterotoxin and TSST-1. For the prevention of a patient to patient-, room to room- and ward to ward-spread, strict isolation was indicated both the infection patients, immunocompromised patients who were at high risk for the infection and the proved carriers. Treatment with VCM was started immediately if MRSA infection was thought plausible. These countermeasures seemed to succeed in reducing the incidence of the infection in our ward.

Anti-Bacterial Agents↗

[Lymphocyte phenotype and cytokine mRNA expression of steady-state asthma BALF cells].

Recently, the roles of inflammatory processes in the pathogenesis of asthma have been emphasized. To elucidate the roles of T lymphocytes in local inflammatory sites in asthma, we examined T cell phenotypes with flow cytometry and carried out cytokine message amplification phenotyping (MAPPing) of bronchoalveolar lavage (BAL) cells taken from patients with steady-state asthma (n = 11). The percentage of CD4+ T cells in total lymphocytes correlated significantly (r = 0.784, p < 0.005) with that of lymphocytes in total CD45+ BAL cells. The positivities of T cell activation markers (CD25, HLA-DR) in CD4+ T cells were inversely correlated with the ratio of CD3+ T cells to total CD45+ BAL cells (CD25, r = 0.648, p = -0.059, HLA-DR, r = -0.741, p < 0.05). Most CD4+ T cells were of the CD45 RO+ "memory" phenotype. With cytokine MAPPing, IL-2 or IFN gamma were detected in only 2 of 11 patients, but IL4 or IL-5 were detected in 8 patients. These results suggest that non-activated TH2 type memory CD4+ T cells accumulate in local inflammatory sites of the bronchi of patients with steady-state asthma, and that these cells releases cytokines (IL-4, IL-5) when activated by some stimuli, which can lead to an asthma attack.

Adult↗

[Hepatitis B virus antibody positive spastic paraparesis].

We present here thirteen patients (5 men and 8 women, aged 31 to 73, mean 55 years) with spastic paraparesis who showed clinical features similar to those of HTLV-1 associated myelopathy without HTLV-1 antibody, but with positive antibody to hepatitis B virus (HBV). All of these patients showed slowly progressive difficulty in walking. Five patients had previous histories of blood transfusion, of these one with history of B hepatitis. Neurologically, muscle weakness, spasticity and exaggerated deep tendon reflexes in the lower extremities were common to all the patients. Seven patients showed Babinski's reflex. Disturbance of micturition was noted in 3 patients. None showed organic changes of the spine on magnetic resonance image (MRI). None was serologically positive for syphilis and had cryoglobulin and hypergammaglobulinemia. Elevated levels of the liver enzymes were noted in two patients. All patients were positive for hepatitis B surface antibody (HBs-Ab) (EIA) but negative for hepatitis B surface antigen (HBs-Ag) (EIA). Five patients were seropositive for hepatitis C virus (HCV) (PHA). In 3 of them, reverse transcriptase polymerase chain reaction was performed but failed to detect HCV-RNA. All patients underwent spinal tap, and showed normal cell count and protein concentration in their cerebrospinal fluid (CSF). Atypical cells were not observed in all the patients. The CSFs from three patients were tested for HBs-Ag and HBs-Ab. HBs-Ag was negative in all three patients, but HBs-Ab was positive in two patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Tissue-specific distribution and age-dependent increase of human CD11b+ T cells.

Distribution of CD11b Ag, a member of the leukocyte integrin (beta 2 integrin) family, on human T cells is not well characterized. We investigated in this study the tissue distribution and age-related alteration of human CD11b+ T cells. Significant proportions of CD11b+ cells were found in T cells from adult peripheral blood (18-58 yr) (20%), liver (32%), and spleen (16%), but were rarely observed in those from thymus, lymph nodes, intraepithelial lymphocytes, lamina propria lymphocytes, and lung. In contrast, percentages of CD28+ T cells, a counter population of CD11b+ T cells, were highest in lymph nodes (91%), modest in intraepithelial lymphocytes (82%), lamina propria lymphocytes (77%), PBL (77%), spleen (73%) and lower in thymus (62%), lung (60%) and liver (56%). The CD11b+ T cells from peripheral blood gradually increased with age, whereas the CD28+ T cells showed an age-dependent decrease. Namely, the percentages of CD11b+ T cells were 6% in newborns (cord blood), 15% in young adults (18 to 22 yr), 25% in middleaged adults (45 to 58 yr), and 27% in aged adults (72 to 86 yr), whereas those of CD28+ T cells were 96%, 83%, 72%, and 71%, respectively. Proportions of CD11b+ T cells in TCR-gamma delta+ or CD8+ T cells were, respectively, higher than those in TCR-alpha beta+ or CD4+ T cells. Age-dependent increase of CD11b+ T cells in CD8+ T cells was more obvious than that of CD4+ T cells. Furthermore, CD11b+ CD28+ T cells increased in the peripheral blood only of aged adults. The percentage of CD11b+ CD28+ T cells in TCR-gamma delta+ T cells was highest in young adults (25%), whereas that in CD4+ T cells was highest in aged adults (15%). CD11b+ CD28+ T cells expressed much potent IFN-gamma, IL-2, and IL-4 at mRNA level than CD28+ CD11b- T cells or CD11b+ CD28- T cells, and had potential cytotoxic activity. Roles of CD11b+ T cells in vivo were discussed.

Adolescent↗

Rapid diagnosis of cytomegalovirus and Pneumocystis carinii pneumonia by using the capillary polymerase chain reaction.

We attempted to detect cytomegalovirus DNA (CMV-DNA) and Pneumocystis carinii DNA (P. carinii-DNA) in sputum samples of 18 hematological neoplasm patients with pneumonia, using rapid cycle DNA amplification. A thermal cycler based on recirculating hot air was used for rapid temperature control of 10-microliters samples in this glass capillary tubes. After a total amplification time of 15 min, the amplified products were electrophoresed on agarose gels and visualized with ethidium bromide. In three cases, CMV-DNA was detected at about the time the pneumonia occurred. These patients were successfully treated with ganciclovir in the early stages of infection and CMV was not detected by the virus culture method. In four other cases, P. carinii-DNA was detected in their sputum samples but not detected by Grocott staining. These four cases of P. carinii were successfully treated with sulfamethoxazole-trimethoprim. For detection of CMV-DNA and P. carinii-DNA using the capillary polymerase chain reaction (PCR), a different temperature setting base on the primer difference was not necessary. Therefore, capillary PCR was performed at the same time for detection of CMV and P. carinii. We conclude that capillary PCR amplification is a valuable tool for rapid diagnosis and early treatment of pneumonia due to CMV and P. carinii.

Adult↗

[Detection of Chlamydia pneumoniae by polymerase chain reaction].

We aimed at developing a method for early detection of Chlamydia pneumoniae (C. pneumoniae) from clinical specimens. For this purpose, we amplified C. pneumoniae-specific DNA fragments by polymerase chain reaction. A pair of 24 mer of oligonucleotides which were complementary to the sequences within the region encoding the major outer membrane were synthesized and used as primers. As the results, all three standard strains of C. pneumoniae (AR-39, TW-183 and AR-388) were identified by the detection of the amplified products of 174 base pairs, while each strain of Chlamydia trachomatis and Chlamydia psittaci and a total of 11 strains of bacteria and a strain of Mycoplasma pneumoniae were not. Thus, the present method was found to provide a very high specificity and also a high sensitivity of a detectable level of 10 x 10(-9) inclusion-forming units.

Base Sequence↗