Biomedical subjects

M Tatemichi

Publications and source records attributed to M Tatemichi.

16 recordsLinked to original sources

PubMed2005

The out-patient management of patients with acute mild-to-moderate colonic diverticulitis.

BACKGROUND: There are no management criteria for optimum out-patient care in mild-to-moderate acute colonic diverticulitis. AIM: To enable such patients to be managed in an out-patient setting, by establishing criteria and treatment protocols. METHODS: We conducted an open trial and follow-up study from 1997 to 2002. On the basis of ultrasonography, we defined and categorized mild-to-moderate acute colonic diverticulitis ranging from limited inflammation within diverticulum to an abscess < 2 cm in diameter. Subjects were treated as out-patients and followed a 10-day treatment protocol consisting of an oral antibiotic and a sports drink for the first 3 days. Physical examination and laboratory testing helped determine whether or not a patient could resume a liquid diet on day 4, and a regular diet on day 7. RESULTS: Of the 70 patients, 68 were successfully treated. Two patients required hospitalization. Of the 65 patients who were tracked over several months [median (intraquarter range) = 30.8 (11.9-44.2) months], 16 had one or more clinical recurrences. The medical cost per episode was 80% lower than in-patient treatment. CONCLUSIONS: Patients with mild-to-moderate acute colonic diverticulitis can be safely and successfully treated as out-patients using this protocol.

Acute Disease↗

PubMed2001

Effect of smoking on serum pepsinogen I level depends on serological status of Helicobacter pylori.

Serum pepsinogen (sPG) levels are used in gastric cancer screening programs. However, modification of sPG levels by smoking habit, according to the status of Helicobacter pylori (H. pylori) infection has been little investigated. This study investigated the effects of smoking on serum levels of pepsinogen I (PG I), pepsinogen II (PG II), and gastrin by IgG titer of antibody against H. pylori (Hp-IgG titer) using the data from 356 current-smokers and 262 non-smokers (133 never-smokers and 129 ex-smokers) in a cross-sectional study of 618 men aged 40 to 49 years. PG I, PG II, PG I / PG II ratio and gastrin were significantly associated with Hp-IgG titer in never-smokers [Spearman's correlation coefficient (95% confidence interval): 0.23 (0.07, 0.39), 0.52 (0.41, 0.63), -0.40 (-0.54,-0.27), and 0.25 (0.10, 0.41), respectively]. However, the correlation coefficients of PG I and PG II decreased in current-smokers, 0.02 (-0.1, 0.13) and 0.32 (0.22, 0.42), respectively. In H. pylori seronegative and low titer cases, the mean PG I level was significantly (P < 0.01) higher in current-smokers, compared with non-smokers. However, in high titer cases, the mean PG I level was lower in current-smokers. Mean PG II and gastrin levels, and PG I / PG II ratio did not differ according to smoking habits by Hp-IgG titer. The gastrin level was significantly correlated with PG II, but not PG I. These data indicate that current smoking influences the serum PG I level depending on Hp-IgG titer and the associations between sPGs and Hp-IgG titer. Gastrin is not involved in the modification of PG I levels by smoking.

Adult↗

PubMed2001

A novel method for detecting single glandular intestinal metaplasia in the mucosal surface of the fixed stomach using methylene blue.

A close association between intestinal metaplasia of the stomach and the well-differentiated type of gastric cancer is well recognized. The etiological relationship and how intestinal metaplasia contributes to gastric carcinogenesis are, however, still unclear. In order to answer this question, precise mapping and identification of the smallest lesion of intestinal metaplasia are desired. Establishment of an accurate and easy method for detecting intestinal metaplasia was the goal of this study. Surgical specimens of stomachs resected for gastric cancer were used. The specimens were stained with methylene blue, an oxidation-reduction marker, in whole mount, after fixation with 4% paraformaldehyde in 0.1 M phosphate buffer (pH 7.4), and observed under a stereo-microscope. Normal gastric mucosa was stained blue, whereas intestinal metaplasia mucosa was not stained and had white or sky-blue island-like features. Intestinal metaplasia of complete type was unstained and showed white island-like features, while intestinal metaplasia of incomplete type showed sky-blue staining. With this method, we were able to detect even intestinal metaplasia composed of a single gland, when the intestinal metaplasia was of complete type. When stomach samples were stained in the presence of diphenyleneiodonium chloride (DPI), an inhibitor of nicotineamide adenine dinucleotide phosphate reduced form (NADPH) reductase, all the samples were homogeneously stained blue. Loss of the color of methylene blue was caused by the reductase activity of NADPH reductase, which is strongly and specifically expressed in intestinal metaplasia. A novel method for detecting intestinal metaplasia, even a single gland, was established.

Coloring Agents↗

PubMed2001

Meta-analysis for epidemiologic studies on the relationship between smoking and Parkinson's disease.

Many epidemiologic studies on the relationship between smoking and Parkinson's disease (PD) have been conducted. Morens et al. reviewed many articles in the study field and concluded that smoking is inversely associated with the risk of PD. In the present study, the object is to obtain summarized risk estimates of the relationship from the published articles using meta-analysis. Summarized risk estimates on the relationship between smoking and PD were found to be about 0.5 with statistical significance in meta-analysis. Therefore, the result that smoking is inversely associated with the risk of PD is appropriate.

Analysis of Variance↗

PubMed1999

Mutagenic activation of environmental carcinogens by microsomes of gastric mucosa with intestinal metaplasia.

Coexpression of cytochrome P450 monooxygenases (CYPs) and reductase was found in human gastric mucosa with intestinal metaplasia. Immunohistochemistry showed reactivity to P450 reductase in metaplastic epithelial cells and in pyloric gland cells in glands showing intestinal metaplasia. These cells exhibit NADPH-diaphorase activity. Reverse transcription-PCR analysis and Western blotting showed that CYP1A1 and CYP1A2 were expressed in specimens with intestinal metaplasia. Tissue distribution of CYP1A1 coincided with that of P450 reductase. However, immunoreactivity to CYP1A2 protein was localized only in the pyloric gland cells near the intestinal metaplastic gland. Salmonella typhimurium mutagen assay definitively revealed that microsomes prepared from gastric mucosa with intestinal metaplasia, in particular in the pyloric gland, functionally activated benzo(a)pyrene and 2-amino-3-methylimidazo [4,5-f]quinoline. These results indicate that carcinogen activation by CYP enzymes expressed in the gastric mucosa may contribute to carcinogenesis of the stomach.

Carcinogens, Environmental↗

PubMed1999

Is endoscopic paravascular injection of sclerosing agents reasonable in the control of GI bleeding?

BACKGROUND: The pharmacologic response and microvascular effects associated with the endoscopic injection of sclerosing agents around vessels (paravascular injection) to stop bleeding from the digestive tract remain to be clarified. METHODS: Using in vivo microscopy, we directly visualized submucosal microvessels of the rat stomach and intestine. We studied differences among sclerosing agents in thrombus formation and vascular diameter change that occur through a pharmacologic response and/or local compression after topical application or paravascular injection of the agents. RESULTS: Except for absolute ethanol, topical application of the agents did not cause constriction or thrombi in either arterioles or venules. Polidocanol topical application and paravascular injection significantly dilated arterioles. Injecting ethanolamine oleate near venules constricted them the longest and most effectively, but vasoconstriction in arterioles was transient. Injecting absolute ethanol formed long-lasting thrombi and caused vasoconstriction in venules, but arteriole thrombi persisted no more than 3 minutes. The vascular response to thrombin did not significantly differ from that to physiologic saline. CONCLUSION: The paravascular injection of ethanolamine oleate, because of its long-lasting vasoconstriction, or of absolute ethanol, because of its thrombogenic effect, is a valid therapeutic approach to treating venous bleeding. The efficacy of paravascular injection of sclerosing agents for treating acute arterial bleeding, however, is not supported in this experimental model.

Animals↗

PubMed1998

Enhanced expression of inducible nitric oxide synthase in chronic gastritis with intestinal metaplasia.

Nitric oxide produced by inducible nitric oxide synthase (iNOS) has been claimed to be involved in gastritis; however, its characteristics are largely unknown. We assessed (1) iNOS expression in the human gastric mucosa in chronic gastritis and (2) the cytokines associated with iNOS expression. Gastric biopsy specimens were obtained from patients with chronic gastritis. Total RNA was isolated and reverse transcription-polymerase chain reaction (PCR) was performed semiquantitatively using specific primer sets for iNOS, interleukin (IL)-1beta, IL-8, IL-6, interferon-y, tumor necrosis factor-alpha (TNF-alpha), TNF receptors, IL-6 receptors, and sucrase, respectively. Helicobacter pylori infection was examined by the PCR assay. Reverse transcription-PCR analysis showed that expression of iNOS was detected in 10 of 23 samples. Expression of iNOS mRNA was closely correlated with expression of TNF-alpha and was observed frequently in subjects with intestinal metaplasia. The Helicobacter pylori gene was detected by PCR assay in all iNOS-positive cases. These results indicate that iNOS is predominantly expressed in the gastric mucosa with intestinal metaplasia and H. pylori infection. TNF-alpha is thought to be an important cytokine associated with iNOS expression.

Adult↗

PubMed1998

Suppression of anti-microtubule agent-induced apoptosis by nitric oxide: possible mechanism of a new drug resistance.

The propensity of a cell to undergo apoptosis has been proposed to be a determinant of sensitivity to anti-microtubule agents. The anti-microtubule agents vincristine and paclitaxel induce key features of apoptosis, such as intranucleosomal DNA fragmentation and changes in nuclear morphology in the human neuroblastoma cell line, NB-39-nu. Nitric oxide (NO) generated from NO-releasing drugs prevented anti-microtubule agent-induced apoptosis in this cell line. The mechanism of suppression of apoptosis by NO appears to be via the inhibition of an interleukin-1beta converting enzyme-like protease cascade. This finding reveals a new biological function of NO, as well as a new molecular insight into resistance to chemotherapy with anti-microtubule agents.

Antineoplastic Agents, Phytogenic↗

PubMed1997

Nitric oxide inhibits CPP32-like activity under redox regulation.

The inhibitory effect of nitric oxide (NO) on the enzymatic activity of CPP32-like proteases in the cell extract from vincristine-treated cells was examined in vitro. NO generated from (+/-)-(E)-methyl-2-[(E)-hydroxyimino]-5-nitro-6-methoxy-S-hexen eamide (NOR1) inhibited CPP32-like protease, which constitute a family of interleukin-1beta-converting enzyme (ICE)-like proteases in a dose-dependent manner. Moreover, recombinant CPP32beta activity was inhibited by NOR1 at same concentration. Inhibition of CPP32-like activity by NO was reversed in the presence of glutathione in the enzymatic reaction mixture. Thus, CPP32-like activity was regulated by NO under redox regulation. These findings suggest that NO may prevent apoptosis by inhibiting the ICE protease cascade under the influence of cellular redox status.

Apoptosis↗

PubMed1997

TNF-alpha mediates inducible nitric oxide synthase expression in human neuroblastoma cell line by cisplatin.

The human neuroblastoma cell line NB-39-nu expressed inducible nitric oxide synthase (iNOS) mRNA following treatment with a combination of interferon-gamma (IFN-gamma) and cis-diamminedichloroplatinum(II) (cisplatin). The level of iNOS mRNA peaked at 48 hr after treatment, and dexamethasone inhibited the induction of iNOS mRNA expression. Cisplatin induced tumor necrosis factor-alpha (TNF-alpha) mRNA expression, and an anti-TNF-alpha neutralizing antibody inhibited the induction of iNOS expression by a combination of cisplatin and IFN-gamma in NB-39-nu cells. Thus, iNOS expression in NB-39-nu cells by a combination of cisplatin and IFN-gamma involves in the TNF-alpha-mediated signal transduction mechanism.

Antineoplastic Agents↗

PubMed1997

Sleep characteristics of Japanese working men who score alexithymic on the Toronto Alexithymia Scale.

This study examined the relationship of sleep characteristics including insomnia with scores on alexithymia in a sample of 171 Japanese working men. Levels of nonrestorative sleep and daytime sleepiness reported on a sleep questionnaire were significantly associated with scores on Depression and Confusion on the Profile of Mood States for Japanese men who had a high mean score on the Toronto Alexithymia Scale.

Adaptation, Psychological↗

PubMed1996

Differences in hemostasis among sclerosing agents in endoscopic injection sclerotherapy.

Endoscopic injection sclerotherapy is useful in stopping bleeding from esophageal varices. We compared the in vivo effects of sclerosants on thrombogenesis, hemostasis, and endothelial injury. We injected aethoxysclerol (AS) of ethanolamine oleate (EO) into the small veins of the rat intestine. The maximum thrombogenic index with AS was 30.7 and with EO was 9.2. The venous flow stopped sooner with EO than with AS. The thrombi caused by EO were mixed with red blood cells. Heparin pretreatment decreased the thrombogenic index with AS by 96.7%, but not that with EO. The area of the fluorescein-albumin conjugate that permeated from veins with AS was larger than that with EO. The fluorescent intensity with AS was lower than that with EO. We thus conclude that: (1) the size of thrombi is not necessarily proportional to the hemostatic efficacy; (2) change in a patient's coagulation may affect the potential of sclerosants; (3) the excellent hemostatic efficacy of EO is based on localized injury to the endothelium and the involvement of red blood cells aggregation; and (4) in vivo microscopy is useful in determining the rational selection of sclerosants.

Animals↗

PubMed1996

Adenosine A2-receptor mediates ethanol-induced arteriolar dilation in rat stomach.

Topical application of ethanol to the gastrointestinal mucosa induces vasodilation. Using an in vivo microscopy technique, we studied the effect of topical ethanol on the submucosal microvessels that control mucosal blood flow in the rat stomach and identified vasoactive substances and receptors that mediate the ethanol vasoaction. Topical ethanol (1-20%) dilated submucosal arterioles dose dependently, but did not change venular diameters. An inhibitor of alcohol dehydrogenase, 1 mM 4-methylpyrazole, did not alter the ethanol vasoaction. Ethanol-induced arteriolar dilation was eliminated by adenosine deaminase, but other vasodilator inhibitors such as atropine, pyrilamine, indomethacin, human calcitonin gene-related peptide-(8-37), and N omega-nitro-L-arginine methyl ester did not prevent it. Ethanol-induced arteriolar dilation was inhibited by an adenosine A2-receptor antagonist, but not by an A1-receptor antagonist, whereas an A2-agonist, but not an A1-agonist, dose dependently dilated arterioles. Exogenous adenosine (10(-5)-10(-3) M) dilated arterioles to a similar extent as ethanol. This response was inhibited by an A2-antagonist. We conclude that nonmetabolized ethanol increases gastric mucosal blood flow via A2-receptors in submucosal arterioles.

Animals↗

PubMed1995

[Health appraisal for work adjustment of freshmen employees--information on health checkup just after entering the corporation and condition in the next fiscal year].

In 1990, 365 (males: 197, females: 168) freshmen employees at the headquarters of a large corporation were examined just after being hired in order to observe their health status. We collected (1) data of physical examinations and questionnaires for symptoms as an ordinary health checkup, (2) information on work adjustment, life patterns, and personal characteristics through interviews conducted by ten public health nurses, and (3) personal records, e.g. birth year. Statistical analyses revealed some notable findings as follows: (1) subjects with higher blood pressure had higher scores of extrovert personality among males, (2) female subjects with greater body mass index had higher scores in such manifestations of personal characteristics such as aggression and discontent with superiors, (3) higher scores of personal characteristics were noted among female subjects working in technical sections, (4) positive correlation between the scores of work adjustment and personal characteristics, (5) higher scores of undesirable life patterns among males and of work maladjustment among elder females, (6) unbalanced meal quality of subjects from rural areas, (7) higher mental tension among younger males from rural areas, and (8) higher scores of dependency and lower morale among younger female subjects. Information on health problems was collected over the 1.5 yrs that followed. More problems were detected among females than among males and among younger females than among elder females. Longitudinal analysis was carried out from just after entry into the company for approximately 1.5 yrs. Health problems in females could be predicted by the data on personal characteristics and work adjustment just after entry. Risk of health problems in male freshmen employees with hobbies and unhealthy drinking habits over the 1.5 yrs that followed was higher than in others. It was concluded that a health interview for freshmen employees by public health nurses is valuable for health care, obtaining information regarding work adjustment, life patterns, and personal characteristics.

Adult↗

PubMed1994

In vivo visualization of lymphatic microvessels and lymphocyte migration through rat Peyer's patches.

BACKGROUND/AIMS: In the small intestine, lymphocytes migrate through Peyer's patches. The distribution of lymphatic microvessels in rat Peyer's patches and lymphocyte traffic through them were studied. METHODS: Vital dyes were injected via a micropipette into the Peyer's patches tissue to fill lymphatic microvessels and to stain lymphocytes in lymphatic microvessels. RESULTS: Direct microscopic observation revealed a dense plexus of lymphatic microvessels in the perifollicular and interfollicular areas. Injection of the dyes into the germinal center failed to delineate lymphatic microvessels. The lymphatic microvessels in the perifollicular area were filled with lymphocytes. Most lymphocytes in the perifollicular lymphatics stayed in the lymphatic microvessels. Some lymphocytes became detached and drained into lymphatic microvessels in the interfollicular areas. Lymphocytes then moved toward the submucosal lymphatics beneath the villi around the Peyer's patches. The interfollicular lymphatics did not display contractile activity but had valves. Opening and closing of valves was synchronized with the respiration and the back and forth flow of lymphocytes. CONCLUSIONS: There are numerous lymphocytes in a dense lymphatic network in the perifollicular and interfollicular areas of Peyer's patches. This well-developed lymphatic network has the potential capacity for storage of lymphocytes and modulation of lymphocyte migration.

Animals↗

PubMed1993

Protein-losing enteropathy caused by mesenteric vascular involvement of neurofibromatosis.

A 44-year-old man with neurofibromatosis suffered from severe diarrhea and progressive hypoproteinemia. Enteric protein loss was confirmed by an alpha 1-antitrypsin clearance test. An x-ray study showed irregular mucosa in the distal segment of the ileum. Protein loss has subsided after ileocecal resection. Laparotomy and radiological examinations failed to demonstrate neurofibroma or other tumors in the abdomen. The resected ileum revealed marked edema of the wall and a pseudomembranous enteritis-like appearance in the luminal surface. Microscopically, lymphatic vessels in the intestinal wall were dilated. Marked thickening of the intima with spindle cell proliferation was observed in the mesenteric arteries and veins. This finding is consistent with vascular changes in neurofibromatosis. These vascular changes in the mesentery due to neurofibromatosis may cause protein-losing enteropathy by altering the hemodynamic state and microvascular permeability in the intestine.

Adult↗