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Biomedical subjects

H Hotta

Publications and source records attributed to H Hotta.

At least 145 records · Page 8Linked to original sources
PubMed1985

Enhancement of dengue virus infection in cultured mouse macrophages by lipophilic derivatives of muramyl peptides.

Dengue virus multiplication in cultures of a murine myelomonocytic cell line (WEHI-3) as well as mouse peritoneal macrophages was enhanced by treatment of the cells with lipophilic derivatives of muramyl peptides for 2 or 3 days before virus inoculation, but not for 2 hr before virus inoculation or during the adsorption period. The infection-enhancing activity of the materials was dependent on their chemical structure, correlating with their immunoadjuvanticity. The infection enhancement in WEHI-3 cells was due primarily to an increase in the number of virus-infected cells which was accompanied by an increased cellular capacity to bind latex particles to their cell surfaces.

Acetylmuramyl-Alanyl-Isoglutamine↗
PubMed1985

Preretinal and retinal hemorrhage due to chronic subdural hematoma.

A case report of a 58-year-old man with preretinal and retinal hemorrhages due to chronic subdural hematoma is presented. Three weeks after head injury in a motor vehicle accident, a few peripapillary retinal hemorrhages with slightly blurred margins of the optic disk were seen in both eyes; subretinal and preretinal hemorrhages developed subsequently. Computed tomography revealed right frontal subdural hematoma, though there were no neurologic findings. Preretinal hemorrhages associated with subdural hematoma are uncommon in adults, and no photographic evidence of such hemorrhages has been published. The patient was treated nonsurgically, and the ocular hemorrhages resolved gradually.

Hematoma, Subdural↗
PubMed1984

Dengue type 2 virus infection in human peripheral blood monocyte cultures.

Dengue type 2 virus (D2V) infection in cultured human monocytes was studied. D2V permissiveness of the monocytes was enhanced when the cells were inoculated with D2V in the presence of either polyclonal or type-specific monoclonal anti-dengue antibody. The enhancement of D2V permissiveness mediated by the antibodies was more clearly demonstrated when the monocytes had been treated with trypsin before virus inoculation, though treatment of the cells with trypsin alone decreased D2V permissiveness. The enhancement of infection by type-specific neutralizing monoclonal antibody suggests that the D2V particles possess at least two antigenic determinants closely associated with virus infectivity. Infectious center assays revealed that the infection enhancement in the presence of the antibodies was due primarily to an increase in the number of D2V-infected cells, and that only a small proportion of the monocyte population supported D2V replication. The virus-permissive monocytes did not bear HLA-DR antigens on their cell surface. The presence of nonadherent lymphocytes in the monocyte cultures before D2V inoculation did not affect the D2V permissiveness of the monocytes. Treatment of cultured monocytes with the synthetic adjuvants N-acetylmuramyl-L-alanyl-D-isoglutamine (MDP) and its lipophilic derivative, [B30]-MDP, did not significantly affect the D2V permissiveness of the cells.

Acetylmuramyl-Alanyl-Isoglutamine↗
PubMed1984

Antibody-mediated enhancement of dengue virus infection in mouse macrophage cell lines, Mk1 and Mm1.

Antibody-mediated enhancement of dengue type 2 virus (D2V) replication in murine macrophage cell lines (Mk1 and Mm1) was studied. While both Mk1 and Mm1 supported D2V replication in the absence of enhancing antibodies, virus production was enhanced when both cell lines were inoculated with D2V in the presence of dengue type 1 virus (D1V)-hyperimmune rabbit IgG, D1V-hyperimmune mouse ascitic fluids, or D2V-hyperimmune mouse ascitic fluids at subneutralizing concentrations. The enhancement ratios were greater in Mk1 than in Mm1. Type-specific neutralizing monoclonal anti-D2V antibody also mediated D2V replication enhancement in Mk1 to the same extent as mediated by three other enhancing antibodies described above. In contrast, however, the same monoclonal antibody mediated only a slight and smaller magnitude of D2V replication enhancement in Mm1 than did the other enhancing antibodies. Fluorescent antibody observations revealed that virus replication enhancement in both Mk1 and Mm1 was due primarily to an increase in the numbers of virus-infected cells. D2V infection enhancement in Mk1 by the anti-D2V mouse ascitic fluids at a dilution showing nearly 50% plaque-reduction activity was markedly suppressed by addition of complement to the inocula, whereas that by the monoclonal antibody, which has been identified as mouse IgG1, was not. Phagocytoses of tritiated thymidine-labeled bacteria by Mk1 and Mm1 were also enhanced when the bacteria had been opsonized with antibody. The phagocytosis enhancement ratios were again greater in Mk1 than in Mm1.

Animals↗
PubMed1984

Effect of interferons on dengue virus multiplication in cultured monocytes/macrophages.

The effects of interferons on dengue virus multiplication in cultured human and mouse monocytes/macrophages were studied. Interferon treatment before, but not after virus inoculation suppressed virus multiplication dose-dependently. Recombinant human leukocyte A interferon was as effective as ordinary human fibroblast interferon in suppressing dengue virus multiplication in cultured human monocytes. Human monocytes, a population of non-proliferating cell lineage, maintained their interferon-mediated antiviral state for a few days after removal of the interferons.

Animals↗
PubMed1983

Enhancement of dengue virus type 2 replication in mouse macrophage cultures by bacterial cell walls, peptidoglycans, and a polymer of peptidoglycan subunits.

The effects of bacterial cell walls, peptidoglycans, and a water-soluble polymer of peptidoglycan subunits on dengue virus type 2 replication in cultured mouse peritoneal macrophages were studied. Pretreatment of macrophage cultures with all of test cell walls isolated from seven bacterial species for 3 days significantly enhanced the virus production in the cultures. Peptidoglycans prepared from four of the above cell walls also exerted the virus production-enhancing effects in a similar manner as the walls. A water-soluble polymer of peptidoglycan subunits which was prepared by treatment of Staphylococcus epidermidis wall peptidoglycan with an interpeptide bridge-splitting enzyme (endopeptidase) also definitely enhanced the virus production in macrophage cultures, although its activity was weaker than that of the original wall and peptidoglycan. Macrophage cultures from athymic nude mice, when treated with cell walls and peptidoglycans of S. epidermidis and Lactobacillus plantarum for 3 days, also showed an increased ability to support dengue virus type 2 replication. The infectious center assay demonstrated that the virus replication enhancement by S. epidermidis cell wall and peptidoglycan was primarily due to an increase in the number of virus-infected cells. This finding did not seem to be in conflict with the observation that macrophages treated with the above cell wall or peptidoglycan phagocytized more latex particles than did untreated macrophages. The conclusions based on the above experiments are that the treatment of mouse peritoneal macrophage cultures with bacterial cell walls and their components increases the take of dengue virus type 2 by macrophages and thus raises the virus production in the macrophage cultures.

Animals↗
PubMed1983

[Hypothalamic histiocytosis X--report of a case].

Histiocytosis X is a non-neoplastic disorder of unknown etiology characterized by a mass of proliferating histocytes, plasma cells and inflammatory cells forming a granuloma within the reticuloendothelial elements of any organ system in the body. The three clinical syndromes of this condition, eosinophilic granuloma, Hand-Schüller-Christian disease and Letterer-Siwe disease were unified into a single nosological entity by Lichtenstein in 1953. The complication of the central nervous system is shown in the cerebrum, cerebellum, sella turcica, hypothalamus and so on. Hypothalamic histiocytosis X is often found in cases of disseminated histiocytosis X, but an isolated histiocytosis X of the hypothalamus is very rare. Including our case, 16 cases of hypothalamic histiocytosis X were reviewed in this paper. Age at onset was older than disseminated histiocytosis X. The sex ratio was almost equal. Diabetes insipidus was equally found as in other suprasellar masses and it was important as an initial symptom. The CT finding was shown as a homogeneously enhanced mass but no specific finding of CT was seen as suprasellar histiocytosis X. Therefore, differential diagnosis was very difficult. Treatments for this disease were variable. Chemotherapy, irradiation or combination of both were reported. The combination therapy was thought to be the most effective treatment. The relation between this disease and disseminated histiocytosis X is not known. But possibility of transformation of this disease into disseminated histiocytosis X was reported in some papers. Therefore, early diagnosis by biopsy of the hypothalamic lesion was stressed.

Adult↗
PubMed1982

Dengue virus multiplication in cultures of mouse peritoneal macrophages: effects of macrophage activators.

Dengue-2 virus multiplied in cultures of methylcellulose-induced peritoneal macrophages of BALB/c mice. The in vitro-cultivated macrophages from dengue-1 virus-immune mice produced larger amounts of dengue-2 virus than did those from nonimmune controls. The effect of macrophage activators was examined by using nonimmune macrophages. Enhanced virus production was demonstrated in cultures of macrophagges pretreated with phytohemagglutinin (PHA) or bacterial lipopolysaccharide (LPS). The number of virus-infected cells in the pretreated cultures was estimated to be about 0.01% or less of the total macrophages. Continuous treatment of macrophages with PHA before and after virus inoculation brought about the most marked enhancement of dengue-2 virus multiplication. On the other hand, treatment with concanavalin A or pokeweed mitogen showed little effect on the multiplication of the same virus. Treatment with carrageenan, a specific macrophage blocking agent, markedly suppressed dengue-2 virus production in both dengue-1 virus-immune macrophages and LPS-treated macrophages. The indirect fluorescent-antibody (FA) technique revealed dengue-2 viral antigen in the cytoplasm of infected macrophages, and the FA-positive macrophages were more numerous in PHA-treated cultures than in untreated controls. The results obtained are discussed in relation to a possible role of activated monocytes/macrophages in the pathogenesis of dengue hemorrhagic fever.

Animals↗
PubMed1982

[Fracture of the sella turcica--a case report and review of the literature].

The incidence of a fracture of the sella turcica is reported to be rare and the authors reported a case of a sellar fracture associated with several neurological and endocrinological complications. A 16-year-old boy was struck at the face and the forehead on the road in a motorcycle accident and was hospitalized in a confusional state. Neurological examinations showed dilatation of the both pupils, sluggish light reflex on both sides and bilateral oculomotor palsy but motor weakness or sensory disturbance was not present. On the tenth hospital day, he developed diabetes insipidus and endocrinological examinations disclosed the impairment of GH, LH and FSH reserves, too. Neuroradiological examinations disclosed fractures of bilateral frontal bones and fractures of the left optic canal and ethmoidal roof as well as a fracture of the sella turcica. On the 28th hospital day, he also developed CSF rhinorrhea and pneumocephalus. Surgical repair for the CSF rhinorrhea was performed. Fractures of the sella turcica were reviewed in 23 cases including our personal case and a special consideration regarding the mechanism of sellar fractures and their major complications was made. The authors stressed the early recognition of a fracture of the sella turcica in head injuries, which would suggest a severe hypothalamo-pituitary involvement or other neurological disorders.

Adolescent↗
PubMed1981

Inoculation of dengue virus into nude mice.

When athymic nude (nu/nu) and heterozygous littermate (nu/+) mice were injected intraperitoneally (i.p.) with a mouse-adapted strain of dengue virus (DV), the following differences were noted in the course of infection. (i) The average survival time of nu/nu mice was longer than that of nu/+ mice, although the mortality ratios were not significantly different. (ii) DV persisted in some of the nu/nu mice for long periods of time without exhibiting any symptoms but they died after prolonged incubation periods. These aspects were not observed in the nu/+ mice. (iii) Infected nu/nu mice produced IgM antibody only transiently in the early stage of infection but they did not subsequently show regular IgG antibody production which normally occurred in nu/+ mice. (iv) Piamatral and perivascular mononuclear cell infiltration in the infected brain was more intense in nu/+ than in nu/nu mice. It is suggested from these data that the course of DV infection in mice is affected by the availability of thymus-derived lymphocytes (T-cells). Infectious virus was detected in various organs and tissues of infected mice. The hearts of nu/nu mice tended to show higher virus titres than those of nu/+ mice, whereas the virus concentrations in the brain, skeletal muscle and lymph node were the same in both groups of mice. Specific DV antigen was revealed by the fluorescent antibody (FA) technique in cells located in the infected tissues.

Animals↗
PubMed1978

Pulmonary alveolar proteinosis: analysis of pulmonary washings.

Bronchopulmonary washings from a patient with pulmonary alveolar proteinosis who underwent therapeutic pulmonary lavage were examined. There were large amounts of protein and lipids of which main classes were phospholipid, cholesterol and free fatty acid. The major component of phospholipids recovered from the washings was lecithin rich in palmitic acid. We also found a high IgG level in the washings. Both the findings of free cholesterol in high concentration in the washings and the electrophoretic pattern of protein in the washings suggested that the alveoli-filling material of our patient was not wholely derived from passive transudation of plasma constituents.

Adult↗