Search PubMed⌕ Search

Biomedical subjects

H Ohtomo

Publications and source records attributed to H Ohtomo.

At least 55 records · Page 3Linked to original sources
PubMed1991

[Studies on tsutsugamushi disease in Gifu prefecture. 4. Survey results in Ena and Takayama City, and the summary of the studies in the prefecture].

Investigations of trombiculid mites and Rickettsia tsutsugamushi in wild rodents were made in Ena (Nov. 1988) and Takayama (May 1989) City. In the former area where no patient has been reported so far, Leptotrombidium pallidum (63.9%) was most predominant and no L. scutellare was found. A Karp-related rickettsia (11.1%) was isolated from wild rodents and 30% of them had antibody to R. tsutsugamushi (anti-Karp was prominent). The latter area where patients were reported in spring as well as in autumn, L. pallidum (22.4%) was one of the dominant species in spring. Karp-related strains were isolated from 37.5% of wild rodents. And the antibody possession rate was 50.0%. These data reconfirmed our hypothesis that the majority of patients in autumn were infected by L. scutellare and a part by L. pallidum. In spring in Takayama area, the vector was L. pallidum which possessed Karp-related strain(s).

Animals↗
PubMed1991

[Cryptosporidium diarrhea developing in two Japanese adults--one in AIDS and the other in a normal host. Research Group for Infectious Enteric Diseases, Japan].

Case I: A middle-age homosexual male developed AIDS with Pneumocystis carinii pneumonia (PCP) and esophageal candidiasis in 1986 during his stay in an European country about five months prior to transfer to Tokyo Metropolitan Komagome Hospital, Tokyo, in 1987. He was also diagnosed as having cryptosporidiosis presenting with mild diarrhea a month following the diagnosis of PCP. Diarrhea was successfully treated with spiramycin. On transfer to Tokyo Metropolitan Komagome Hospital, he was febrile but had no diarrhea. Serum HIV and TPHA were positive and his blood lymphocyte subset T4a was markedly decreased. On the 13th day after transfer to the hospital, watery diarrhea appeared. Cryptosporidium oocysts were detected from the feces taken on the 17th hospital day. The patient died of Escherichia coli septicemia on the 38th hospital day. Autopsy finding yielded Cryptosporidium infection widely spread over the stomach, ileum, bile and pancreatic ducts. Case II: A 31-year-old previously healthy female presented with abrupt onset of mucous stool five times daily. Mucous passage continued on the subsequent days despite administration of loperamide, and the passage increased to 20 times daily with mucous to watery diarrhea associated with mild abdominal cramps and nausea on the 4th day after onset of illness. On the 6th day of illness, she visited Tokyo Metropolitan Komagome Hospital. She denied close contact with pet animals or contact with any person presenting diarrhea. She had no recent history of travelling anywhere outside Tokyo. On examination she was an apparently healthy woman except for a slightly distended abdomen with localized tenderness in the right upper quadrant.(ABSTRACT TRUNCATED AT 250 WORDS)

Acquired Immunodeficiency Syndrome↗
PubMed1991

[A case report of a patient repeatedly infected with Ancylostoma duodenale, probably from himself through his artificial anus, and resistant against a single dose of pyrantel pamoate].

A 88 year old Japanese male was repeatedly infected with Ancyclostoma duodenale. He underwent an artificial anus operation about 55 years ago. He appeared to be infected with hookworm earlier than in 1977 and developed severe anemia. Though he was treated with pyrantel pamoate and mebendazole several times, reinfections developed in each time. A possible origin for his reinfections was his own feces defecated through his artificial anus. Unsanitary handling of the anus and the feces exposed himself to oral or percutaneous infection. Besides, a single dose of pyrantel pamoate, usually very effective against Ancylostoma duodenale, was not so effective in this patient. Therefore, we prescribed multiple doses of pyrantel pamoate, and followed by a single dose of mebendazole. However, reinfections still persisted because of his unsanitary behavior.

Aged↗
PubMed1991

A modified agar plate method for detection of Strongyloides stercoralis.

The agar plate method is a new technique with high detection rates for coprological diagnosis of human strongyloidiasis. This report details modifications of the technique and establishes a standardized procedure. We recommend that all plates should be carefully observed using a microscope because macroscopic observation can lead to false negative results. It is also advisable to pour formalin solution directly into microscopically positive dishes to collect worms by sedimentation. This procedure enables one to observe worms otherwise hidden. Sealing dishes with adhesive tape prevents larvae from crawling out of the dishes, eliminating any possibility in the reduction of detection rates, and greatly improves the safety conditions for the technician performing the procedure. We consider the agar plate method to be superior to the filter paper method in detecting Strongyloides, and we believe that it will eventually become the technique of choice.

Animals↗
PubMed1990

Lethal efficacy of extract from Zingiber officinale (traditional Chinese medicine) or [6]-shogaol and [6]-gingerol in Anisakis larvae in vitro.

The authors previously reported that an extract from Zingiber officinale, traditionally eaten along with raw fish and used in traditional Chinese medicine, effectively destroyed Anisakis larvae in vitro. In this study, we analyzed the effective components of ginger rhizomes. Methanol extracts were fractionated after first being treated with HCl at pH 3, then with NaHCO3 at pH 10, and, finally, with NaOH at pH 13 (fraction 1). In general, this fraction is rich in neutral substances. [6]-Shogaol and [6]-gingerol, known neutral components of ginger rhizomes, were detected using gas chromatography and were found to be the most prevalent components in the fraction, occurring in quantities that resulted in a dose-dependent killing efficacy. Authentic [6]-shogaol and [6]-gingerol could kill Anisakis larvae at a minimal effective dose of 62.5 and 250 micrograms/ml, respectively. However, the concentration of [6]-gingerol in fraction 1 was greater than 20 times that of [6]-shogaol, making the former the most active component in the fraction. Furthermore, synergistic effects between [6]-gingerol and a small amount of [6]-shogaol were observed. Pyrantel pamoate, an available antinematodal drug, had no lethal effect, even at a concentration of 1 mg/ml. In saline solution containing [6]-shogaol (62.5 micrograms/ml), greater than 90% of larvae lost spontaneous movement within 4 h and were destroyed completely within 16 h. Microscopical examinations showed destruction of the digestive tract and disturbances of culticulae.

Animals↗
PubMed1990

Trombiculid mites (Acari: Trombiculidae) and Rickettsia tsutsugamushi isolated from wild rodents in a new endemic area of Japan.

Investigations of trombiculid mites and Rickettsia tsutsugamushi in wild rodents were made in southern Gifu Prefecture where patients infected with tsutsugamushi disease recently have been found. A total of 16,396 trombiculid mites, consisting of 10 species from three genera, was collected from 170 Apodemus speciosus in two locations. Kani-Sakahogi and Kuze. Leptotrombidium scutellare (Nagayo et al.) (44.0%) was most predominant, followed by L. pallidum (Nagayo et al.) (26.9%); L. fuji (Kuwata et al.) (13.6%); and Gahrliepia saduski Womersley (14.2%). These four species constituted the bulk of the chigger mite fauna. L. scutellare was present from October to February with a remarkably high peak in November, whereas pallidum occurred from November to March with the highest peak in December. L. fuji and G. saduski showed their highest peaks in December and moderate peaks in early summer (April and May). Positive identification of Rickettsia tsutsugamushi in wild rodents from Kani-Sakahogi were found to be 50 and 58.3% in November 1985 and 1986, respectively, and 38.5% in November 1986 from Kuze. R. tsutsugamushi was isolated from chigger mites of an L. pallidum-rich group, displaying the highest titer to Karp strain. Serological investigation of rodents to R. tsutsugamushi antibodies were calculated as 41.6 and 50% positive in November 1985 and 1986 in Kani-Sakahogi, respectively, and 50% in November 1986 in Kuze. The Karp strain was dominant in specificity to antibodies. These results indicate that the surveyed areas have a high probability of occurrence of tsutsugamushi disease, and L. scutellare and L. pallidum may serve as the vectors in these areas. Particularly, we suggest that L. scutellare is the most important vector which has caused a recent outbreak of this disease in southern Gifu Prefecture.

Animals↗
PubMed1990

[Fundamental studies on serological diagnosis of amoebiasis. 2. Application of antigen of Entamoeba histolytica for complement fixation test to counterimmunoelectrophoresis; and clinical relevance of serological tests].

Antigen of Entamoeba histolytica for complement fixation (CF) test was applied to counterimmunoelectrophoresis (CIE), and the result was compared with that of CF test and enzyme-linked immunosorbent assay (ELISA) in regard to sensitivity and specificity. Besides, we studied antibody titers to E. histolytica in sera from acute and convalescent patients, and from patients with amoebic colitis and amoebic liver abscess. Sera used were from patients with amoebic colitis, amoebic liver abscess and uninfected control subjects. The CIE was less sensitive than the CF test and ELISA. Most CIE-negative samples had low CF and ELISA titers, but a few samples had higher CF and ELISA titers. On the other hand, all uninfected controls were negative by CIE and ELISA, and 98% were negative by the CF test. The level of antibodies tended to decrease with time after clinical recovery, but CF test and ELISA results remained positive in all patients 6 months after clinical cure. CIE converted negative in only one patient after 6 months. The level of antibodies of CF test and ELISA was significantly higher in amoebic liver abscess than amoebic colitis. These results suggested that all these three methods were so specific, and antibody titers by the CF test and ELISA were well correlated to clinical manifestations. The CIE with CF-antigen was less sensitive as compared with CF test or ELISA.

Animals↗
PubMed1990

[Fundamental studies on serological diagnosis of amoebiasis. 1. Application of amoebic antigen for CF test to ELISA].

We studied the establishment of enzyme-linked immunosorbent assay (ELISA) using amoebic antigen for complement fixation (CF) test. Optimal dilution for ELISA of sera from patients was 1:100, and that of CF-antigen was 1:400. The upper limit of the 99% critical range of the reaction of negative sera was 0.068 (cut-off level). Absorbance of sera from patients diluted 1:100 to antigen and antibody titers of ELISA were strongly correlated, so it was possible to estimate antibody titers from absorbance of serum diluted 1:100. ELISA and CF test were done to compare sensitivity of the tests using 63 sera from patients with invasive amoebic disease. The sensitivity of ELISA compared well with CF test (62 sera were positive by ELISA and 61 by CF test). Only one sample was both positive by ELISA and negative by CF test. This sample had low ELISA titers, so this discrepancy was mainly due to the sensitivity of CF test in detecting lower levels of antibody. These results suggested that the amoebic antigen for CF test can be applicable to ELISA, and this method was so sensitive and specific.

Amebiasis↗
PubMed1989

Significance of blood urea nitrogen as an index of renal function in mice infected with Plasmodium berghei.

Parameters of renal function were evaluated in severe malarial infection, using mice infected with Plasmodium berghei. When 7-week-old male BALB/c mice were inoculated with 1 x 10(7) P. berghei NK65-infected red blood cells, the rodents died an average of 7.4 days after inoculation. Anemia developed on day 5 after inoculation and progressed markedly on days 6 and 7. Plasma urea nitrogen increased rapidly on day 6 or 7, after which death occurred within 24 h. In contrast, urinary urea nitrogen excretion decreased on the same day. Urinary beta-N-acetyl-D-glucosaminidase (NAG) activity increased from day 3 to day 5, then decreased to normal levels on day 7. Renal ATP concentration and energy charge decreased markedly on day 7. These data indicate that the blood oxygen supply to the tissues began to decrease on day 6 and that renal insufficiency developed in the terminal stage of infection. We concluded that even a moderate increase in the level of plasma urea nitrogen could be a useful index of renal insufficiency in this infection system.

Acetylglucosaminidase↗
PubMed1989

Eosinophilia in mouse regulated by multiple factors following repeated stimulations with ascaris eggs into the peritoneal cavity.

Repeated injections of viable eggs of Ascaris suum into the peritoneal cavity of BALB/c mice induced marked peritoneal eosinophilia (9.3 X 10(6) cells/mouse, 52.8%) without infection. Extracted antigen (Asc) and eggs that had been killed also were able to induce marked eosinophilia; however, their levels were significantly lower (p less than 0.001). This experimental system was able to demonstrate how various multiple factors cumulatively affected the degree of peritoneal eosinophilia. These factors included: mechanical stimulation, caused by the repeated peritoneal lavages (4.4 X 10(5) cells/mouse), against a background level of peritoneal eosinophils of 4.5 X 10(4) cells/mouse; T-cell-independent stimulation, observed when the viable eggs were injected repeatedly into athymic nude mice (nu/nu; 1.6 X 10(6) cells/mouse), while on the other hand, neither eggs that had been killed nor Asc displayed any T-cell-independent augmentation of eosinophilia; and, T-cell-dependent augmentation of peritoneal eosinophilia, observed in heterozygous athymic mice (nu/+), in thymocyte-reconstituted nu/nu, and in normal BALB/c mice. Egg culture supernatant could not act on bone marrow cells to support eosinophil colony formation. In conclusion, only viable eggs were considered prime inducers, consisting of T-independent and T-dependent parts exerting cumulative effects.

Animals↗
PubMed1987

Pathophysiology of hypoxia in mice infected with Plasmodium berghei.

Pathophysiological significance of hypoxia in malarial infection was investigated in mice infected with Plasmodium berghei NK65. Intraperitoneal inoculation of mice with 1 X 10(7) parasitized red blood cells resulted in death of the hosts 6-7 days later. Anaemia of infected animals developed on day 4 after inoculation and oxygen affinity of whole blood, measured as P50 act pH, increased simultaneously. This change may be a physiological adaptive response to a reduction in oxygen delivery to the tissues to day 5. However, the blood oxygen supply on day 6 appeared to be deteriorating and this is thought to be an important factor contributing to the death of the host. The value of adenylate energy charge in red cells during malarial infection, however, was comparatively well-maintained. Allopurinol stimulated the multiplication of malaria parasites and seems to have induced collapse in host-parasite balance more rapidly. Decrease in blood pH and in blood oxygen transport may be important factors for the pathogenesis of the allopurinol-treated hosts.

Adenine Nucleotides↗
PubMed1987

Clinical evaluation of antimalarial regimens in Japan.

The actual situation of the treatment of malaria for the past 10 years in Japan was investigated and analyzed. As a result, it was revealed that there were not a few cases which had been treated improperly probably because of the difficulty of getting antimalarial agents. Moreover, it was made clear that the death rate on falciparum malaria was constantly high, 8.7%, as expected and the relapse rate of vivax malaria was still as high as 18.0%. There was the recrudescence of falciparum malaria at 8.1%, maybe because of the influence of the prevalence of the drug-resistant strains of Plasmodium falciparum. The trouble in getting antimalarial agents has been overcome since 1980. Study Group on Pharmacotherapy of Imported Tropical Diseases was organized by the Ministry of Health and Welfare in 1980, and antimalarial agents have been supplied free of charge through the Study Group for the treatment of the disease. The number of cases of imported malaria has increased in our country. There are a lot of problems to be solved quickly to cope with the situation: people who travel abroad should be enlightened on the danger of the infection of malaria and take prophylactics for the disease and physicians should get familiar with the disease being supplied with information about it.

Animals↗
PubMed1987

Activation autoradiography: imaging and quantitative determination of endogenous and exogenous oxygen in the rat brain.

Endogenous and exogenous oxygen in the rat brain were quantitatively determined using an autoradiographic technique. The oxygen images of frozen and dried rat brain sections were obtained as 18F images by using the 16O (3He,p)18F reaction for endogenous 16O images and the 18O(p,n)18F reaction for endogenous and exogenous 18O images. These autoradiograms demonstrated the different distribution of oxygen between gray and white matter. These images also allowed differentiation of the individual structures of hippocampal formation, owing to the differing water content of the various structures. Local oxygen contents were quantitatively determined from autoradiograms of brain sections and standard sections with known oxygen contents. The estimated values were 75.6 +/- 4.6 wt% in gray matter and 72.2 +/- 4.0 wt% in white matter. The systematic error in the present method was estimated to be 4.9%.

Activation Analysis↗