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Biomedical subjects

H Sagara

Publications and source records attributed to H Sagara.

At least 19 recordsLinked to original sources

Present characteristics of symptomatic Entamoeba histolytica infection in the big cities of Japan.

Medical records, for 2000 and 2001, of symptomatic amoebic patients who were treated at our hospitals in Tokyo, Yokohama and Osaka were studied retrospectively for the purpose of gathering epidemiological data on symptomatic Entamoeba histolytica infection. A total of 58 patients were treated. Fifty-five of them were male, and 96% of the male patients were Japanese. The mean age of patients was 44.9 years old, and 91% of patients contracted the disease in Japan. Fifty-six per cent of the male patients indicated that they were practising homosexuals, and 44% of the male patients denied these practices or left the question unanswered. The serum Treponema pallidum haemagglutination test was positive in 45% of the patients, and antibody to human immunodeficiency virus (HIV) was positive in 45%. Our study revealed that recent symptomatic E. histolytica infection almost exclusively afflicted middle-aged males in the big cities of Japan, that a majority of the patients were probably exposed to the causative organism during homosexual activity, and that an increasing number of patients will be co-infected with HIV.

AIDS Serodiagnosis↗

Allergen activates peripheral blood eosinophil nuclear factor-kappaB to generate granulocyte macrophage-colony stimulating factor, tumour necrosis factor-alpha and interleukin-8.

BACKGROUND: Allergic inflammation is characterized by the influx and activation of eosinophils. Cytokines generated by both resident and infiltrating cells are responsible for the initiation and maintenance of this pathogenesis. This study focuses on allergen-induced activation of eosinophil NF-kappaB and generation of granulocyte macrophage-colony stimulating factor (GM-CSF), TNF-alpha, and IL-8. METHODS: Peripheral blood eosinophils were enriched to >99.9% by Percoll gradient sedimentation and negative magnetic affinity chromatography. NF-kappaB activation by 10 microg/mL house dust mite (HDM) extract was demonstrated immunocytochemically using a monoclonal antibody against the active form of NF-kappaB (NF-kappaBa). The authenticity of NF-kappaB was confirmed by Western blot. Cytokine production was assessed both by immuno-staining of eosinophils and by assay of cytokines in the cell supernatant. RESULTS: Activation of peripheral blood eosinophils from atopic, but not non-atopic, donors induced activation of NF-kappaB, which peaked at 4 h and was accompanied by a decline in IkappaB-alpha. The activation of authentic NF-kappaB was confirmed in gel shift assays. Supershift assays showed p65 to be the major subunit of eosinophil NF-kappaB. Immunofluorescent confocal microscopy demonstrated localization of NF-kappaBa to the nucleus. Following activation, cytokine immunoreactivity was seen in a fraction of the eosinophils and cytokines were released into the supernatant. The NF-kappaB inhibitors, calpain inhibitor 1 (10 microm), pentoxifylline (0.5 mm), pyrrolidine dithiocarbamate (PDTC, 10 microm) or gliotoxin (1 pg/mL) reduced the generation of GM-CSF, TNF-alpha and IL-8 in parallel with their inhibition of NF-kappaB. CONCLUSIONS: HDM allergen activates human eosinophil NF-kappaB leading to the production of the cytokines GM-CSF, TNF-alpha and IL-8. We speculate that a role for eosinophil NF-kappaB-dependent cytokines is to act as an autocrine loop augmenting the survival of eosinophils in vivo.

Analysis of Variance↗

Involvement of complement and fibronectin in eosinophil-mediated damage to Nippostrongylus brasiliensis larvae.

By using IL-5 transgenic mice, it has been shown that eosinophils might play a key role in elimination of larval stages of nematode infections. The present study was carried out to clarify molecular mechanisms involved in the eosinophil-mediated killing of Nippostrongylus brasiliensis larvae. The larvicidal activity was observed in the presence of normal serum in vitro. Electron microscopic observations revealed firm attachment of eosinophils to the cuticular surface of larvae, which was damaged by electron-dense materials released from eosinophils. The larvicidal activity was abrogated by heat- or zymosan-treatment of the serum, whereas depletion of IgG or IgM from the serum did not interfere with eosinophil adhesion and killing. Moreover, pretreatment of eosinophils with monoclonal antibodies against CD11b or VLA-4 inhibited the eosinophil-mediated killing of larvae. Immunofluorescent staining demonstrated the deposition of C3c and plasma fibronectin on the cuticle of the larvae. These results indicate that interactions between CD11b and VLA-4 and their respective counter-ligands deposited on the cuticle are essential in eosinophil-mediated adhesion and damage to larvae of N. brasiliensis.

Animals↗

[Evaluation of an HIV screening assay kit for the combined detection of anti-HIV-1/2 antibodies and HIV p24 antigen].

We have evaluated a new HIV screening assay kit (Genscreen HIV Ag-Ab) for the HIV antigen-antibody combined test by comparing with two HIV antigen-antibody combined assay kits (VIDAS HIV DUO, Enzygnost HIV integral). Genscreen HIV Ag-Ab is a microwell plate enzyme immunoassay for the detection of HIV infection, based on the detection of anti-HIV-1/2 antibodies and HIV p24 antigen in human serum or plasma. In this study, 90 samples of HIV-1 antibody positive sera and 670 samples of HIV negative sera were examined. The sensitivity was 100% and the specificity was 99.7%. All of HIV-1 group M sera (subtypes A to G and B/D), HIV-1 group O sera and HIV-2 sera in worldwide HIV performance panel-302 were positive with Genscreen HIV Ag-Ab. Ten commercially available HIV-1 seroconversion panels were tested to evaluate sensitivity of three HIV antigen-antibody combined assay kits. Genscreen HIV Ag-Ab detected infection at the same bleeds as VIDAS HIV DUO in 8 of 10 seroconversion panels and 1 to 2 bleeds earlier than Enzygnost HIV integral in 5 of 10 seroconversion panels. However, VIDAS HIV DUO indicated false negative on 5th bleed in panel BB (PRA952). The result of the specimen was positive on 3rd bleed, equivocal on 4th bleed, negative on 5th bleed and again positive on 6th bleed. All of these specimens were positive by Genscreen HIV Ag-Ab. Therefore, Genscreen HIV Ag-Ab that shorten the window period is a useful and reliable for HIV screening test, especially in case of primary infection.

AIDS Serodiagnosis↗

[A case of leptospirosis infected in Borneo Island, Malaysia].

We report a case of leptospirosis infected in Sabah, Borneo island, Malaysia. The case is 25-year-old male who had participated in the EcoChallenge Sabah 2000 Expedition Race, a multisport event held during August 20 to September 3, 2000 at various sites in Sabah in Malaysian Borneo. He developed a high fever and headache on September 7, and he was admitted to our hospital on September 9. On admission he also had conjunctivitis and myalgias. Laboratory findings on admission revealed leukocytosis with left shift, slightly elevated transaminase levels, high CRP levels and proteinuria. Plasmodium spp. were negative on blood smears, and no bacteria were isolated from blood and feces cultures. We performed the laboratory tests for leptospirosis, based on the information about the probable leptospirosis outbreak among athletes who participated in the EcoChallenge Race, however both Leptospira antigens and antibodies were negative at that time. We diagnosed leptospirosis clinically because he manifested persistent symptoms, and minocycline 100 mg b.i.d. was administered intravenously resulting in excellent efficacy. Serum antibody tests by microscopic agglutination test (MAT) at convalescent stage revealed significant increased antibodies against Leptospira interrogans serovar hebdomadis, and the diagnosis of leptospirosis was confirmed. Infectious diseases have been global and it is important to have information concerning worldwide infectious disease situations as much as possible for accurate diagnosis.

Adult↗

Antibiotic susceptibilities of Salmonella enterica serovar Typhi and S. enterica serovar Paratyphi A isolated from patients in Japan.

The antibiotic susceptibilities of 62 strains of Salmonella enterica serovar Typhi and 37 strains of S. enterica serovar Paratyphi A were investigated with 18 antibiotics. Eighteen S. enterica serovar Typhi isolates and five S. enterica serovar Paratyphi A isolates were resistant to one or more antimicrobial agents, among which 10 S. enterica serovar Typhi isolates were nalidixic acid resistant and also showed decreased ciprofloxacin susceptibility.

Anti-Bacterial Agents↗

[HIV-1 (human immunodeficiency virus type 1) mutant strain associated with zidovudine resistance detected from a Japanese patient with primary HIV-1 infection].

Sequences of HIV-1 pol gene were determined by direct sequencing from a Japanese patient with primary HIV-1 infection. The patient did not receive antiretroviral therapies. However we observed a HIV-1 mutant strain associated with zidovudine (ZDV) resistance. The patient had both the codon 70 and the codon 215 amino acid substitutions in the RT region. Our data indicated that the patient was infected with a HIV-1 mutant strain associated with ZDV resistance and this is the first report in Japan.

Acquired Immunodeficiency Syndrome↗

[Gastrointestinal diseases associated with HIV infection].

A clinical studies were carried out on gastrointestinal diseases associated with HIV infection. During the 6 years between January 1993 and December 1998, 71 HIV infected cases visited to Yokohama Municipal Citizen's hospital, and 26 of them developed gastrointestinal complications during the course of their illness. They consisted of 24 males and 2 females, with the mean age of 44.7 years and the medial value of 42.5 years. Of the 26 patients, 21 were Japanese, and the remaining 5 were Southeast Asian. The mean CD4 count was 143/microliter and the medial value was 32/microliter at the time of development of complications. Gastrointestinal complications were esophageal candidiasis in 6 patients, cytomegalovirus (CMV) gastritis and gastric Kaposi's sarcoma in 1 patient each, amebiasis in 8 patients, infectious colitis in 11 patients, and asymptomatic pathogen carriers in 3 patients. Esophageal and gastric complications were common in patients with low count of CD4, and endoscopy was useful for diagnosis. Amebiasis developed even in patients with normal CD4 and was common in males with experience in homosexual contact. It seems that homosexual contact acquire not only HIV infection but also Entamoeba histolytica through sexual contact. Protozoan and acid-fast bacteria were detected at high rate in patients with infectious colitis and asymptomatic pathogen carriers. Besides food-born infections, imported infections were seen in foreign and Japanese patients who had traveled abroad. The gastrointestinal diseases associated with HIV infections for the most part were opportunistic infections or tumors but imported, food-born, and sexually transmitted infections were also observed. It seems necessary to take into consideration of varying background of patients in the treatment of gastrointestinal diseases associated with HIV infections.

AIDS-Related Opportunistic Infections↗

Scattered fat invasion: an indicator for poor prognosis in premenopausal, and for positive estrogen receptor in postmenopausal breast cancer patients.

BACKGROUND: Intracrine mechanisms which accelerate cancer cell growth are becoming well known in breast cancer research. In this study, microscopic invasive patterns of breast cancer cells into surrounding stromal tissues were evaluated. PATIENTS AND METHODS: 174 patients (110 patients < or = 50, and 64 > or = 60 years) underwent total or partial mastectomy from 1985 to 1993. In these patients the microscopic invasive pattern (especially scattered invasion into fat, SIF), influence on hormone receptor status, survival, and adjuvant therapy effectiveness were studied. RESULTS: A correlation was shown between being SIF- and estrogen receptor-positive only in older (> or = 60 years) patients (chi(2) test, p = 0.058). In younger patients, SIF was also related to a poorer prognosis (log rank test, p = 0. 0004). These results were also confirmed by multivariate analysis. Adjuvant therapy activity was influenced by SIF status in premenopausal patients. CONCLUSION: In older patients, SIF may be related to an intracrine supply of estrogen. In younger patients, SIF seems to work by a different mechanism for survival. These results also suggest some influence of SIF on adjuvant chemo-endocrine therapy results.

Adipose Tissue↗

Oral administration of fluoroquinolones in the treatment of typhoid fever and paratyphoid fever in Japan.

OBJECTIVE: To study the adverse reactions and therapeutic effects of fluoroquinolones to investigate whether they can be used for the treatment of patients with typhoid fever and paratyphoid fever. METHODS: The adverse reactions and therapeutic effects of fluoroquinolones were studied retrospectively in patients with typhoid fever and paratyphoid fever. PATIENTS: 58 patients (54 Japanese) with typhoid fever, 42 patients (41 Japanese) with paratyphoid fever, and 1 Japanese patient with both typhoid fever and paratyphoid fever, who were admitted in hospitals in Tokyo, Kawasaki, Yokohama, Kyoto, and Osaka from 1995 to 1998 and treated with fluoroquinolones. RESULTS: Almost 80% of the patients were treated with tosufloxacin (TFLX) and the remaining 20 % were treated with norfloxacin, ciprofloxacin, levofloxacin, or sparofloxacin. Side effects (nausea, urticaria, aphthous stomatitis) and elevation of serum amylase were found in 3.6% and 8.3 % of patients treated with TFLX, respectively, but these adverse reactions disappeared in all of these cases either with or without a change in the drug used. No adverse reactions were found in patients treated with the other fluoroquinolones. The clinical and bacteriological effects of these drugs were adequate. CONCLUSION: Though further studies still need to be performed on the fluoroquinolones other than TFLX, we can preliminarily conclude that fluoroquinolones are safe drugs and they can be recommended for the initial therapy of patients with typhoid fever and paratyphoid fever.

Administration, Oral↗

A case of Penicillium marneffei infection in an AIDS patient: the first case in Japan.

A 38-year-old Japanese AIDS patient developed papular lesions which rapidly increased in number, eroded and crusted, and spread over not only skin but also the mucosal surface. High fever, sore throat, malaise and hepatosplenomegaly were also noted, and he died despite 2 months of intensive treatment. An autopsy revealed numerous histiocytes infected with Penicillium marneffei in the lymph nodes, liver, spleen, bone marrow, skin, and mucosal surface of the oral cavity to the pharynx. This case is thought to be the first Japanese case of penicilliosis marneffei.

AIDS-Related Opportunistic Infections↗

[Comparison between repeated antigen and acetylcholine-induced bronchoconstriction in development of airway wall thickness in a chronic guinea pig model of asthma].

Asthma is associated with a chronic remodeling of the airways, but it remains to be elucidated whether repeated bronchoconstriction (BC) influences any structural attributes of the lungs. To investigate the role of repeated BC on the morphology of the airways, we chronically exposed guinea pigs to an aerosol of acetylcholine (ACH) over a period of 6 months. The guinea pigs were challenged with either ACH or saline daily for 10 days and thereafter were challenged once a week. To compare repeated BC with a chronic model of allergic inflammation, an additional group of animals were sensitized to aerosolized ovalbumin (OA) and subsequently exposed with OA. The airway wall area and basement membrane (BM) thickness were measured by standard morphometric techniques. Both airway wall area and BM thickness were significantly increased in OA exposed guinea pigs compared with both saline control and AHC-exposed guinea pigs. Our results suggest that persistent bronchoconstriction and/or allergic airway inflammation in asthmatics may contribute to the thickness of the airway wall observed in this disorder. However, repeated acute bronchoconstriction events may not contribute to the increase in the airway wall or BM thickness.

Acetylcholine↗

Electronic network for monitoring travellers' diarrhoea and detection of an outbreak caused by Salmonella enteritidis among overseas travellers.

The Traveller's Diarrhoea Network, by which the Infectious Disease Surveillance Center is electronically connected with two major airport quarantine stations and three infectious disease hospitals, was launched in February 1988 in Japan. The data on travellers' diarrhoea detected is reported weekly by e-mail. Two clusters of infection among travellers returning from Italy were reported by two airport quarantine stations at the end of September 1998. A total of 12 salmonella isolates from 2 clusters were examined. All were identified as Salmonella enteritidis, phage type 4 and showed identical banding patterns on pulsed-field gel electrophoresis. A case-control study showed that the scrambled eggs served at the hotel restaurant in Rome were the likely source of this outbreak. This outbreak could not have been detected promptly and investigated easily without the e-mail network. International exchange of data on travellers' diarrhoea is important for preventing and controlling food-borne illnesses infected abroad.

Adult↗