Biomedical subjects

T Okuyama

Publications and source records attributed to T Okuyama.

At least 37 records · Page 2Linked to original sources

PubMed2001

Biomedical and psychosocial determinants of psychiatric morbidity among postoperative ambulatory breast cancer patients.

There has been much interest in the psychosocial issues faced by breast cancer patients because of the high prevalence of the disease and the severe psychological impact of the cancer itself, as well as its treatment. The objective of our study was to investigate the determinants of psychiatric morbidity among postoperative ambulatory breast cancer patients. The variables examined included the patients' biomedical characteristics, demographic characteristics, current concerns, coping responses and social support factors. Patients completed the Hospital Anxiety and Depression Scale (HADS) and the Mental Adjustment to Cancer scale (MAC scale), and information pertaining to demographic variables, current concerns and social support factors was obtained by a specially designed questionnaire. Available data were obtained from 148 randomly selected postoperative ambulatory breast cancer patients. The prevalence of psychiatric morbidity (including clinical anxiety and depression) evaluated by using the HADS cut-off point was 23%. The results of univariate analyses indicated that pain, dyspnea, having children with health problems, various other concerns (about children, other family members, the patients' own health and future treatment) and poor coping responses (low fighting spirit, high anxious preoccupation, high fatalism and high helplessness/hopelessness) were significant determinants of the patients' psychiatric morbidity. Additionally, in the logistic regression analysis, having children with health problems and having a low fighting spirit and a high helplessness/hopelessness were final significant determinants. Postoperative ambulatory breast cancer patients with these problems should be given careful attention, and psychosocial intervention may be beneficial for them.

Adaptation, Psychological↗

PubMed2001

Successful umbilical cord blood transplantation from an unrelated donor for a patient with Epstein-Barr virus-associated hemophagocytic lymphohistiocytosis.

We report a case of a 5-year-old girl with EBV-associated hemophagocytic lymphohistiocytosis (EBV-HLH) who underwent cord blood (CB) stem cell transplantation (CBSCT) from an unrelated donor. The patient presented with persistent high-grade fever and hepatosplenomegaly. Because the disease was refractory to immunochemotherapy according to the HLH94 protocol, she received 2.0 x 10(7) CB nucleated cells/kg body weight (BW) after conditioning with BU/CY/etoposide. No acute GVHD developed, using FK506 for prophylaxis. The neutrophil count reached >0.5 x 10(9)/l by day 21 and the platelet count reached >50 x 10(9)/l by day 84. The patient recovered well with sequelae of neurological deficits more than 10 months after receiving CBSCT, without showing evidence of HLH or chronic GVHD. Real-time PCR proved applicable for estimation of the EBV load in PBMC of the patient. We conclude that CBSCT may be indicated for some cases of refractory EBV-HLH, who have no HLA-matched siblings and are therefore dependent on unrelated marrow donors.

Blood Donors↗

PubMed2001

Intragastric distribution of Helicobacter pylori during short-term omeprazole therapy: study using Carnoy's fixation and immunohistochemistry for detection of bacteria.

BACKGROUND: There is controversy about the effect of acid-suppressive therapy on Helicobacter pylori density and the severity of histological gastritis in the corpus. AIM: To evaluate the precise distribution of H. pylori, both on the surface mucus cells and in the surface mucus gel layer, by using Carnoy's fixation and immunostaining for the detection of bacteria. METHODS: A total of 19 peptic ulcer patients with H. pylori infection were studied. All patients received a 6-week course of treatment with omeprazole (20 mg/day). Before and after the therapy, H. pylori density in Carnoy-fixed tissue sections was examined immunohistochemically. The effect of omeprazole therapy on the severity of gastritis was also evaluated. RESULTS: H. pylori density and the grade of gastritis significantly decreased in the antrum after omeprazole therapy. In the corpus, however, there were no significant changes in H. pylori density or the severity of gastritis after omeprazole therapy. CONCLUSION: Carnoy's fixation and immunostaining was found to be useful for the detection of H. pylori in the surface mucus gel layer as well as on the surface mucus cells in biopsy tissue sections. By using this method, H. pylori density decreased in the antrum, but remained unchanged in the corpus after a 6-week course of omeprazole therapy.

Acetic Acid↗

PubMed2001

Influence of Helicobacter pylori infection and cetraxate on gastric mucosal blood flow during healing of endoscopic mucosal resection-induced ulcers.

BACKGROUND AND AIM: Helicobacter pylori (H. pylori) infection is known to affect the gastric microcirculation, and cetraxate is reported to accelerate gastric ulcer healing, possibly by augmenting gastric mucosal blood flow (MBF). The aim of this study is to clarify the effect of H. pylori infection and cetraxate on MBF during gastric ulcer healing. METHODS: Forty-two patients who had undergone endoscopic mucosal resection (EMR) were studied. Mucosal blood flow was measured by the use of a laser Doppler flowmeter in the surrounding mucosa and at the ulcer margin, before, 1 day, 1 week and 4 weeks after EMR. Helicobacter pylori infection was confirmed by the use of bacterial culture and histology. After EMR, patients were randomly assigned to receive 30 mg lansoprazole (u.i.d; L-regimen) or 30 mg lansoprazole (u.i.d.) with 200 mg cetraxate (q.i.d; LC-regimen) for 4 weeks. RESULTS: The MBF ratio (MBF at ulcer margin/MBF in surrounding mucosa) 1 week after EMR was significantly lower than that before or 4 weeks after EMR only in H. pylori-positive patients treated with the L-regimen. No such decrease in MBF was observed after 1 week in H. pylori-positive patients treated with the LC-regimen or in H. pylori-negative patients. CONCLUSION: A transient decrease in MBF was detected at the ulcer margin during healing of EMR-induced ulcers in H. pylori-infected patients. Cetraxate seemed to prevent this decrease in MBF.

2-Pyridinylmethylsulfinylbenzimidazoles↗

PubMed2001

T cell-mediated cytotoxicity via Fas/Fas ligand signaling in Helicobacter pylori-infected gastric corpus.

BACKGROUND: Helicobacter pylori infection induces T helper-1 immune responses in inflamed mucosa. However, the role of T cell-mediated cytotoxicity in the induction of epithelial apoptosis is still unclear. The aim of this study was to investigate the involvement of the Fas/Fas ligand (Fas/Fas-L) system in the H. pylori-infected gastric corpus. MATERIALS AND METHODS: Gastric fundic biopsy specimens were taken from patients with and without H. pylori infection. The expression of Fas and Fas-L was examined by immunohistochemistry and RT-PCR. Subsets of gastric infiltrating T cells in the biopsy specimens were studied by immunohistochemistry and flow cytometry. In histological sections, apoptosis was detected by the TUNEL method. We studied the in vitro expression of Fas-L in peripheral T cells after stimulation with H. pylori antigen and interferon-gamma (IFN-gamma). The Fas-mediated in vitro cytotoxicity of activated T cells was assessed by flow cytometry. RESULTS: The numbers of CD4+ and CD8+ T cells were greater in H. pylori-infected subjects. Fas expression was abundantly increased on fundic gland epithelium, and Fas-L was detected on lamina propria mononuclear cells in H. pylori-infected mucosa. TUNEL-positive epithelial cells were also increased in H. pylori-infected subjects. H. pylori antigen and IFN-gamma induced Fas-L mRNA expression in both CD4+ and CD8+ T cells. In cytotoxic assay, activated T cells induced apoptosis in AGS cells, which could be significantly inhibited by neutralizing Fas-L antibody. CONCLUSIONS: T cell-mediated cytotoxicity via Fas/Fas-L signaling may contribute to the induction of apoptosis in gastric epithelial cells during H. pylori infection.

Adult↗

PubMed2001

The role of nitric oxide in paraquat-induced cytotoxicity in the human A549 lung carcinoma cell line.

Paraquat (PQ) is a well-known pneumotoxicant that exerts its toxic effect by elevating intracellular levels of superoxide. In addition, production of pro-inflammatory cytokines has possibly been linked to PQ-induced inflammatory processes through reactive oxygen species (ROSs) and nitric oxide (NO). However, the role of NO in PQ-induced cell injury has been controversial. To explore this problem, we examined the effect of NO on A549 cells by exposing them to the exogenous NO donor NOC18 or to cytokines; tumor necrosis factor-alpha, interleukin-1 beta and interferon-gamma, as well as PQ. Although the exogenous NO donor on its own had no effect on the release of lactate dehydrogenase (LDH), remarkable release was observed when the cells were exposed to high concentrations of NOC18 and PQ. This cellular damage caused by 1 mM NOC18 plus 0.2 mM PQ was ascertained by phase contrast microscopy. On the other hand, NO derived from 25-50 microM NOC18 added into the medium improved the MTT reduction activity of mitochondria, suggesting a beneficial effect of NO on the cells. Incubation of A549 cells with cytokines increased in inducible NO synthase (iNOS) expression and nitrite accumulation, resulting in LDH release. PQ further potentiated this release. The increase in nitrite levels could be completely prevented by NOS inhibitors, while the leakage of LDH was not attenuated by the inhibition of NO production with them. On the other hand, ROS scavenging enzymes, superoxide dismutase and catalase, inhibited the leakage of LDH, whereas they had no effect on the increase in the nitrite level. These results indicate that superoxide, not NO, played a key role in the cellular damage caused by PQ/cytokines. Our in vitro models demonstrate that NO has both beneficial and deleterious actions, depending on the concentrations produced and model system used.

Adenocarcinoma↗

PubMed2001

Isolated splenic metastasis of sigmoid colon cancer: a case report.

We report the case of a 62-year-old man who developed isolated splenic metastasis of sigmoid colon cancer. The patient underwent left hemicolectomy for Dukes C sigmoid colon cancer in February 1997. In March 1999, an abdominal CT scan revealed a tumor 3 cm in size at the inferior pole of the spleen. The tumor was hyperechoic on ultrasonography. The serum carcinoembryonic antigen level was normal. Since no other site of recurrence was identified, a splenectomy was performed with a curative intent. At laparotomy, neither hepatic metastasis, peritoneal dissemination, lymph node metastasis nor local recurrence was detected. Histological findings of the splenic tumor were compatible with metastasis of the previously resected sigmoid colon adenocarcinoma. The patient has been disease-free for 19 postoperative months. Immunohistochemical staining for urokinase-type plasminogen activator was positive in primary sigmoid colon cancer and splenic metastasis, but negative in lymph node metastasis; results that possibly reflect the difference in progenitor cells between splenic metastasis and lymph node metastasis or the difference in the microenvironment of cancer cells between the spleen and lymph nodes. Based on the present case, we recommend that clinicians pay close attention to the spleen for the early diagnosis of isolated splenic metastasis when routinely evaluating abdominal CT scans and abdominal ultrasonography following curative resection of primary colorectal cancer.

Abdomen↗

PubMed2001

High preoperative plasma D-dimer level is associated with advanced tumor stage and short survival after curative resection in patients with colorectal cancer.

BACKGROUND: An elevated plasma D-dimer level indicates activation of coagulation and fibrinolysis. Previous studies demonstrated that the preoperative plasma D-dimer level correlates with tumor stage in patients with colorectal cancer. This study examined the relationship between preoperative plasma D-dimer level and both pathological findings and TNM classification and examined the prognostic significance of preoperative plasma D-dimer level. METHODS: Preoperative plasma D-dimer levels were measured in 93 patients who underwent curative resection of colorectal cancer and 40 patients with benign colorectal diseases other than inflammatory bowel disease. The results were analyzed for correlations between preoperative plasma D-dimer levels in patients with colorectal cancer and pathological findings, TNM classification and postoperative survival. RESULTS: Preoperative plasma D-dimer levels were significantly higher in patients with colorectal cancer than in patients with benign colorectal diseases. Plasma D-dimer levels were higher in patients with tumors that were relatively large, had relatively deep wall penetration and were at a relatively advanced TNM stage. Higher preoperative plasma D-dimer levels were significantly associated with shorter postoperative overall survival. Results of analysis with a multivariate proportional hazard model suggested that preoperative plasma D-dimer level was the third strongest prognostic factor; exceeded in importance only by lymph node status and preoperative carcinoembryonic antigen level. CONCLUSIONS: Elevated plasma D-dimer levels in patients with colorectal cancer are associated with relatively advanced tumor stage and short postoperative survival after curative resection. It appears that measurement of preoperative D-dimer level would be useful in the preoperative diagnosis of tumor stage and prediction of postoperative survival.

Colectomy↗

PubMed2001

Hematological studies on black cumin oil from the seeds of Nigella sativa L.

The methanol soluble portion of black cumin oil, which is prepared by compression of seeds of Nigella sativa L., showed inhibitory effects on arachidonic acid (AA)-induced platelet aggregation and blood coagulation. By bioactive assay of AA-induced platelet aggregation, the methanol soluble part was purified to isolate a new compound 2-(2-methoxypropyl)-5-methyl-1,4-benzenediol (1) and two known compounds, thymol (2), carvacrol (3), having very strong inhibitory activity. Further, we then examined the isolated compounds (1-3) and eight related compounds by the screening test for AA-induced platelet aggregation. Compounds possessing aromatic hydroxyl and acetoxyl group had more potent activity than aspirin, which is well known as a remedy for thrombosis.

Animals↗

PubMed2001

Cancer chemoprevention by ginseng in mouse liver and other organs.

Oral administration of red ginseng extracts (1% in diet for 40 weeks) resulted in the significant suppression of spontaneous liver tumor formation in C3H/He male mice. Average number of tumors per mouse in control group was 1.06, while that in red ginseng extracts-treated group was 0.33 (p<0.05). Incidence of liver tumor development was also lower in red ginseng extracts-treated group, although the difference from control group was not statistically significant. Anti-carcinogenic activity of white ginseng extracts, besides red ginseng extracts, was also investigated. In the present study, the administration of white ginseng extracts was proven to suppress tumor promoter-induced phenomena in vitro and in vivo. It is of interest that oral administration of the extracts of Ren-Shen-Yang- Rong-Tang, a white ginseng-containing Chinese medicinal prescription, resulted in the suppression of skin tumor promotion by 12-o-tetradecanoylphorbol-13-acetate in 7,12-dimethylbenz[a]anthracene-initiated CD-1 mice. These results suggest the usefulness of ginseng in the field of cancer prevention.

Animals↗

PubMed2001

In vitro prevention of cell-mediated xeno-graft rejection via the Fas/FasL-pathway in CrmA-transducted porcine kidney cells.

Cell-mediated cytotoxicity may be involved in delayed and/or chronic xenograft rejection in which apoptosis is induced in the grafted cells via the Fas/Fas-ligand (FasL) and perforin/granzyme pathways. One barrier to the potential use of xeonogenic grafts for humans may be Fas/FasL-mediated apoptosis, which would be blocked by the gene expression of cytokine response modifier A (CrmA), a cowpox virus gene product. The purpose of this study is to explore whether crmA is an effective candidate gene for inhibiting apoptosis in an in vitro model of xenograft rejection, using Fas-expressing non-primate cells cultured with a soluble recombinant human FasL (sFasL). A recombinant adenovirus vector expressing CrmA (AxCALNLCrmA) was successfully generated with a Cre-mediated switching system. PK15 cells, derived from a porcine kidney and infected with AxCALNLCrmA and/or AxCANCre at a multiplicity of infection (MOI) ranging from 0.1 to 100, were cultured with human sFasL derived from KFL74.18, a human FasL-overexpressed cell line. The gene-expression level of the PK15 cells was confirmed by CrmA-immune staining. Approximately 70% of the control PK15 cells showed induced apoptosis when cultured with sFasL. In contrast, the apoptosis was dramatically reduced in crmA-gene-transduced PK15 cells. The inhibitory effect of apoptosis increased with an increase in the infection dose of AxCANCre. In addition, the activity of caspases 3 and 8 was significantly inhibited in the crmA-transduced cells. These results indicate that CrmA is an effective gene product for inhibiting Fas/FasL-mediated apoptosis, which suggests the potential therapeutic use of its gene transduction to protect against graft damage due to delayed and/or chronic xenograft rejection.

Animals↗

PubMed2001

Synthesis and properties of optically active 1,1':5',1":5",1"'-hexol (QUANOL).

Optically active (R,R,R)- and (R,S,R)-1,1':5',1":5",1'"-quatemaphthalene-2,2',6',2",6",2"'-hexol (QUANOL) were prepared from (R)-BINOL in five steps. The CD spectrum of (R,R,R)-QUANOL showed a larger A value than those of (R)-BINOL and (R,S,R)-QUANOL, but additivity of the axial chiralities in the A value was not observed. Other basic properties for the use of QUANOL as a chiral ligand are also reported.

Journal Article↗

PubMed2001