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Biomedical subjects

I Kawamura

Publications and source records attributed to I Kawamura.

At least 73 records · Page 4Linked to original sources

Hepatic Abnormalities in Obesity: comparison between mildly obese cases and morbidly obese cases.

Hepatic morphology and clinical course of mildly obese subjects with abnormal liver tests were determined in comparison with those of surgically treated morbidly obese cases. Twenty mildly obese subjects (mean body mass index, 27.9) with elevated serum transaminase levels were followed up on a low-calorie diet. Nineteen morbidly obese patients (mean body mass index, 39.2) had a surgical biopsy at gastric restrictive surgery. In these two groups, the frequency and the severity of hepatic steatosis and fibrosis were comparable, whereas intralobular cell infiltration was somewhat greater in the mildly obese group. Follow-up studies of the two groups showed remarkable improvement of serum transaminase levels, the extent of which was greater in surgically treated cases. Thus, in mildly obese subjects with abnormal liver tests, (1) hepatic histological abnormalities are not milder than those in morbidly obese cases, and (2) Improvement of serum transaminase levels upon diet therapy is less satisfactory than that in morbidly obese cases treated surgically. It is suggested these two groups may not be in the same spectrum of obesity-related hepatic disorders.

Journal Article↗

Mycolic acid-containing glycolipid as a possible virulence factor of Rhodococcus equi for mice.

By the use of various Rhodococcus equi strains differing in the length of carbon chains of glycolipid, we examined whether the glycolipid, glucose monomycolate, was contributing to the virulence of R. equi for mice. R. equi strains with longer carbon chain mycolic acid showed a higher virulence as determined by lethality and granuloma formation in mice than those with shorter ones. When purified glycolipid was injected into mice, granuloma formation and liver damage were most prominent with the glycolipid having longer carbon chain mycolic acid. Only a representative strain with longer carbon chain mycolic acid persisted in the spleen of mice after intravenous injection, while a strain with shorter carbon chain mycolic acid was readily eliminated. These results suggested that glycolipid was at least one of the virulence factors of R. equi and that the carbon chain length of mycolic acid might be critical in the expression of virulence.

Actinomycetales Infections↗

Dissociated development of T cells mediating delayed-type hypersensitivity and protective T cells against Listeria monocytogenes and their functional difference in lymphokine production.

CD4+ T cells mediating both delayed-type hypersensitivity (DTH) and acquired cellular resistance (ACR) were generated in mice after immunization with viable Listeria monocytogenes. In contrast, CD4+ T cells from mice immunized with killed L. monocytogenes in complete Freund's adjuvant were capable of mediating only DTH but not ACR. To determine the functional difference between T cells mediating DTH and T cells mediating ACR, we examined two different populations of T cells for profiles of lymphokine production after stimulation with a specific antigen in vitro. The production of interleukin-2 (IL-2) and IL-3 but not IL-4 was observed in both T cells mediating only DTH and those mediating DTH and ACR. In this respect, both types of T cells could be categorized into the TH1 population, and they produced macrophage chemotactic factor equally well. However, the production of gamma interferon (IFN-gamma) was observed only in T cells capable of mediating both DTH and ACR. This result was confirmed not only by an enzyme immunoassay specific for murine IFN-gamma but also by Northern (RNA) analysis for the detection of IFN-gamma mRNA. These results suggested that the TH1 population may be subdivided further into two distinct subsets and that the ineffectiveness of the killed bacterial vaccine may be partly explained by the dissociated development of T cell function.

Animals↗

Antitumor effects of droloxifene, a new antiestrogen drug, against 7,12-dimethylbenz(a)anthracene-induced mammary tumors in rats.

The antitumor effects of droloxifene (DROL, (E)-alpha-[p-[2-(dimethylamino)ethoxy]-phenyl]-alpha-ethyl-3-stilbeno l), a new antiestrogen drug, on 7,12-dimethylbenz(a)anthracene (DMBA)-induced estrogen-dependent mammary tumors in rats were studied and compared with those of tamoxifen (TAM). Mammary tumors appeared from about 2 months after p.o. administration of DMBA to female rats, and all of them were estrogen receptor (ER) and progesterone receptor positive. DROL and TAM (p.o.) inhibited the growth of the tumors. Both drugs inhibited the binding of 125I-estradiol-17 beta to ER in the cytosol of the tumor in vitro, and the effect of DROL was much stronger than that of TAM. When 3H-estradiol-17 beta (3H-E2) was given s.c. to rats with the mammary tumors, 3H-E2 accumulated in the tumors, uteri and vaginae in which the ER levels are known to be high, but was low in the heart, in which the ER levels are normally low. DROL and TAM decreased the levels of 3H-E2 in the tumors, uteri and vaginae, but had no effect in the hearts. When DROL or TAM was given p.o. to rats daily for 7 consecutive days after administration of DMBA, they inhibited the induction of mammary tumors by DMBA. From these results, DROL inhibits the growth and the initiation of DMBA-induced mammary tumors by inhibiting the binding of estrogen to its receptor.

9,10-Dimethyl-1,2-benzanthracene↗

Orthoses of ventilative plastics.

Plastics are extensively used as a material for orthoses. However, one remaining problem is the ventilation of the orthosis. This is a real problem in countries such as Japan, where it is hot and humid especially in summer. The authors have invented a new orthosis "POROPLAST", which is made of mesh plastic sheets, combined in a cross-like weave. These orthoses provide good ventilation and are very comfortable to wear. They have been fitted to seventy-four cases with satisfactory results.

Dermatitis, Contact↗

[A case of Pickwickian syndrome with improvement of obesity-related sleep apnea following vertical banded gastroplasty].

The patient was 22-year-old male who had suffered from hypermotility during sleep and excessive daytime sleepiness, and 270% in excess body weight. Values of arterial blood gas analysis during sleep were 65mmHg in PaCO2 and 19mmHg in PaO2. He was diagnosed as morbid obesity with Pickwickian syndrome and underwent vertical banded gastroplasty. His body weight decreased from 170kg to 113kg four months after surgery and 107kg one year after surgery. The whole-night polyhypnographic sleep study was performed before and after operation and showed dramatic improvement of apnea index which was calculated by dividing the number of apneas by the total sleep time. We analyzed 199 case reports which had noted symptoms of Pickwickian syndrome between 1963 and 1989 in Japan. In many reported cases, body weight decreased transiently but returned to the level before medical treatment. Under these considerations, gastroplasty is a beneficial surgical treatment for the morbid obesity with Pickwickian syndrome.

Adult↗

In vivo treatment with anti B-220 monoclonal antibody affects T and B cell differentiation.

The B220 cell marker is expressed on B cells and on T cell precursors. In order to determine the involvement of the B220 antigen on murine lymphoid differentiation, we treated 5-10-week-old mice periodically with a specific anti-B220 antibody, RA3-6B2, a non-cytolytic IgG2b. After the third injection, a significant reduction (P less than 0.02) in the number of thymocytes and less dramatically in the number of splenocytes was observed. This reduction was predominantly due to a decrease of cells carrying the following markers: Thy-1.2+, Lyt-1+, Lyt-2.3+, L3T4+, and asGM1+. Mitogenic response to concanavalin A, phytohaemagglutinin and lipopolysaccharide, mixed lymphocyte reaction, cytotoxic T cell activity, and plaque-forming cell generation were significantly decreased after the treatment (P less than 0.01). These results show that the in vivo treatment with anti-B220 monoclonal antibody reduced the number of T and B cells and modified their functional activity. This suggests that the B220 antigen is involved in the maturation of both T and B cells.

Animals↗

[Isolation of group A streptococci from pharyngitis patients of all ages--studies from the clinical and epidemiological standpoint].

During the period from June 1981 through Dec. 1985, isolation of group A streptococci was attempted from throat swabs of pharyngitis patients of all ages, who visited a clinic in the central area of Yokohama-city. The data were analysed clinically and epidemiologically. The results were summarized as follows. 1) Group A streptococci were isolated from 85 (30.5%) out of 279 patients with pharyngitis. This is almost within the range of other reports. 2) During one year in the study period, no isolates of group A streptococci were obtained from throat swabs of 32 controls (healthy persons working in the clinic or patients without pharyngitis). 3) The isolation rate correlated with the presence of pharyngeal purulent exudate and also with high maximum body temperature after onset of the illness. The isolation rate was significantly higher in patients with these two signs than those without them. Therefore, these two signs are useful to predict group A streptococcal pharyngitis prior to laboratory examinations. 4) The isolation rate was high in the age groups under 10 and from 30 to 39. 5) The isolation rate was high in winter and low in summer. 6) The typing test revealed T types 13, 28 and 4 to be relatively frequent isolates.

Adolescent↗

Difference in the induction of macrophage interleukin-1 production between viable and killed cells of Listeria monocytogenes.

T-cell-mediated immunity to Listeria monocytogenes in mice, as determined by delayed-type hypersensitivity and acquired resistance, was induced by immunization with viable bacteria but not with killed bacteria, even when killed cells were injected in a high dose or repeatedly. T cells obtained from mice immunized with viable L. monocytogenes were readily stimulated with killed-bacterial antigens, resulting in T-cell proliferation in vitro and expression of a delayed footpad reaction in vivo. After immunization with killed-bacterial vaccine, T-cell responsiveness to interleukin 2 (IL-2) never developed but a lower level of responsiveness to IL-1 appeared later than with T cells from mice immunized with viable bacteria. When IL-1 production by macrophages was examined in vitro, viable L. monocytogenes stimulated a high level of IL-1 release while killed bacteria did not. Avirulent strains which were ineffective in the induction of T-cell mediated immunity were incapable of inducing IL-1 production as well. The impaired ability of killed bacteria to stimulate IL-1 production was confirmed by the level of IL-1 mRNA expression. These results suggested that the ineffectiveness of killed L. monocytogenes vaccine is not due to loss or lack of antigenic epitopes but may be ascribed to insufficient induction of IL-1 production in the initial stage of the immune response in vivo.

Bacterial Vaccines↗

[Manometric study of vertical banded gastroplasty for morbid obesity].

Morbidly obese patients undergoing vertical banded gastroplasty were studied preoperatively and/or postoperatively to characterize its manometric pattern. The esophageal manometry using station pull through technique involved 14 preoperative patients with a mean age of 28 +/- 7 years who were a obesity index of 220 +/- 32% and 14 postoperative patients with a mean age of 30 +/- 7 years who were a obesity index of 158 +/- 23%. Preoperative lower esophageal sphincter (LES) pressure using gastric base line as O was 16.1 +/- 8.5 cmH2O and a LES length of 3.4 +/- 0.9 cm. Postoperatively, the vertical banded gastroplasty channel had a pressure of 17.7 +/- 7.1 cmH2O and a length of 8.2 +/- 1.7 cm which was higher than gastric base line. No difference was seen between preoperative LES pressure and postoperative channel pressure, however postoperative channel length was significantly (p less than 0.01) larger than preoperative LES length. We concluded that vertical banded gastroplasty for morbid obesity created a longer high pressure zone in accordance with channel which would inhibit reflux of gastric juice.

Adult↗

Enhanced protection of cyclophosphamide-treated mice against infection with Pseudomonas aeruginosa after treatment with Z-100, a polysaccharide-rich extract from Mycobacterium tuberculosis Aoyama B.

We investigated the effect of Z-100, a polysaccharide-rich extract from Mycobacterium tuberculosis strain Aoyama B, on the protection of immunocompromised mice against infection with Pseudomonas aeruginosa. Mice were given cyclophosphamide and then treated with varying doses of Z-100 for 5 days or left untreated. One day after the completion of the treatment, they were challenged with P. aeruginosa and the mortality was scored. A significantly enhanced protection was observed in the treated group and bacterial number in organs was significantly lower compared with non-treated group. Though the activity of phagocytes did not appear to be activated since there was no difference in chemiluminescence response of peritoneal phagocytes between control and Z-100-treated groups, an enhanced accumulation of phagocytes was observed after bacterial challenge in Z-100-treated group. It was suggested that Z-100 is effective in the restoration of impaired resistance of immuno-compromised mice to bacterial infection possibly through a stimulation of phagocyte accumulation into the site of infection.

Adjuvants, Immunologic↗

[A case of obstructive sleep apnea syndrome remarkably improved by gastric restriction surgery].

A 23-year-man with morbid obesity and obstructive sleep apnea syndrome (OSAS) was admitted. He was 170 cm in height and 170 kg in weight. He underwent dietary treatment several times, but his weight returned to its original level, or even higher, within a short period. A diagnosis of OSAS was made by nocturnal polysomnography. In this morbidly obese patient with OSAS a nocturnal sleep apnea study was performed before and after weight reduction surgery (gastric restriction). The postoperative findings revealed a dramatic body weight reduction. At the same time, the results of apnea and oxygen desaturation were remarkably improved too. These results indicate that weight reduction surgery is a definitely effective treatment for morbid obesity associated with OSAS.

Adult↗

[A comparison of gastric bypass and vertical banded gastroplasty for morbid obesity].

We evaluated the effects of gastric bypass (GB) and vertical banded gastroplasty (VBG) for morbid obesity. Among 44 cases of obesity, 10 cases were treated with GB and 34 cases were treated with VBG. The obesity index in GB group was 199 +/- 20% preoperatively, and decreased to 136 +/- 15% at six months, 130 +/- 13% at one year, 131 +/- 14% at three years and 136 +/- 19% at five years postoperatively. On the other hand, the preoperative obesity index 212 +/- 26% in VBG group decreased to 149 +/- 17% at six months, 143 +/- 19% at one year and 144 +/- 18% at three years postoperatively. Obesity index was significantly smaller in GB group within 2 years following surgery, however no difference was seen in weight reduction. Obesity-related complications were markedly relieved postoperatively in both groups in accordance with weight reduction. The results demonstrate that GB and VBG are equally effective to reduce excess weight as well as complications of morbid obesity.

Adult↗

[Study of risk factors for postoperative pulmonary complications following esophageal cancer surgery--multivariate statistical analysis].

In 91 patients undergoing resection and reconstruction of the esophagus for esophageal cancer, risk factors for postoperative pulmonary complications were studied. In order to investigate these factors, multivariate statistical analysis was applied. The incidence of postoperative pulmonary complications was significantly higher in patients over 70 years of age who had poor renal function (PSP15' less than 25%) and had prolonged thoracotomy time (greater than 3 h) by Student's t test. In preoperative pulmonary functions, obstructive respiratory dysfunction (MMF, FEV1.0) correlated well with postoperative pulmonary complications. The analysis of each factor was, however, not enough to predict the risk of pulmonary complications following operation. Meanwhile, risk score (= 2.0 (age) + 1.0 (FVC) + 0.7 (MMF) + 1.5 (PSP15') + 1.8 (thoracotomy time) + 1.7 (postoperative RI] was obtained by multivariate statistical analysis. High incidence (greater than 80%) of pulmonary complications was observed in patients with risk score more than 5.0. It is suggested that using this risk score will be helpful for postoperative pulmonary care.

Esophageal Neoplasms↗

Effect of a traditional Chinese herbal medicine ren-shen-yang-rong-tang (Japanese name: ninjin-youei-to) on hematopoietic stem cells in mice.

Cell dynamics after intraperitoneal (i.p.) and oral administration of a traditional herbal medicine, ren-shen-yang-rong-tang (Japanese name: ninjin-youei-to, NYT), were investigated. When NYT was injected i.p. into C3H/He mice, numbers of spleen and peritoneal cells significantly increased in a dose-dependent manner and showed high levels from 4 to 21 days. Two peaks in the total cell number were observed on days 7 and 14 in the peritoneal cavities and spleen of C3H/He mice administered NYT. A marked accumulation of PMN cells in the peritoneal cavity and spleen was detected at 7 days after injection. The numbers of macrophages and lymphocytes also increased by i.p. administration of NYT. The thymus cell number decreased transiently between 4 and 7 days and thereafter returned to the control level. No significant change in the cell number of lymph nodes was observed. Such cellular accumulation was also detected in C3H/HeJ mice, a nonresponder strain to bacterial endotoxin, and athymic nude mice. The activity of colony-forming units in the spleen (CFU-S) of C3H/He as well as C3H/HeJ mice was markedly augmented by i.p. administration of NYT. NYT induced significant CSF production as detectable by its activity in the sera. In addition, oral administration of NYT for 10 days induced a significant increment of peripheral leukocytes and spleen cells and enhanced CFU-S activity of bone marrow cells as induced by i.p. administration, indicating that NYT acts on hematopoietic stem cells capable of differentiating to lymphocytes, macrophages and PMN cells into the periphery.

Animals↗

In vivo influence of the anti-B220 monoclonal antibody administration of the T cell differentiation in mice.

B220, a pan-B marker, is known to be also expressed on immature T cells of MRL/1pr or other congenic 1pr mice and minor population of immature thymocytes but not on peripheral T cells. In this study, we investigated in vivo the possibility whether B220 is one kind of premature T or prethymic T precursor cell marker as well as a pan-B cell marker. A monoclonal antibody against B220 glycoprotein was intravenously injected every 2 days into various strains of mice. After the third administration of this antibody, thymocytes decreased remarkably compared with those from the rat IgG-treated group, and spleen cells were also reduced significantly. Further, the number of cells expressing Thy-1, Ly-1, Lyt-2, and asialo GM1 (asGM1) in the spleen were significantly reduced. On the contrary, the number of cells expressing surface IgM (sIgM) or B220 were increased by this treatment, especially after the 8th treatment. Some T-dependent immunological functions including mitogenic responses to lectins and cytotoxic T cell activity were markedly suppressed but mixed lymphocyte reaction (MLR) and natural killer (NK) activity were rather augmented. Thus, B220 may be expressed on some kinds of T cell progenitor. Taken together, in vivo treatment with anti-B220 antibody may influence differentiating stages of some T cells from bone marrow progenitors before or just after their homing into the thymus.

Animals↗

Depletion of the surface CD4 molecule by the envelope protein of human immunodeficiency virus expressed in a human CD4+ monocytoid cell line.

A CD4+ human monocytoid cell line, U937, was transfected with a constructed plasmid which has the envelope gene of human immunodeficiency virus under the transcriptional control of the human metallothionein IIA promoter and was cloned thereafter. These cloned cell lines (EH and EL cells) expressed the viral gp160 in the cytoplasm. The expression of surface CD4 antigen examined by Leu3a and OKT4 monoclonal antibodies, however, disappeared completely in EH cells, which produce a larger amount of gp160, while diminishing only partly in EL cells, which produce a smaller amount of gp160. These results indicate that the level of expression of surface CD4 antigen correlates inversely with the amount of intracellular gp160. Moreover, immunoprecipitation studies using lysate from EH cells showed that OKT4 monoclonal antibody precipitated a significant number of CD4 molecules even after surface CD4 disappeared. However, Leu3a monoclonal antibody, which recognizes the binding site for envelope protein, could not precipitate any CD4 molecules in the same cell lysate. Taken together, these results suggested that CD4 molecules are still synthesized normally after the augmented production of gp160 in the cells but form a complex with the envelope protein in the cytoplasm and become unable to be transported to the cell surface, resulting in the observed depletion of surface CD4 antigen. This mechanism may explain the decrease or absence of surface CD4 antigens in human lymphocytes infected with human immunodeficiency virus.

Antigens, Differentiation, T-Lymphocyte↗