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Biomedical subjects

D Hashimoto

Publications and source records attributed to D Hashimoto.

At least 19 recordsLinked to original sources
PubMed2006

Interstitial lung diseases associated with amyopathic dermatomyositis.

The aim of the present study was to clarify the clinical characteristics and prognosis of patients with interstitial lung disease (ILD) associated with amyopathic dermatomyositis (ILD-ADM). The study consisted of 14 consecutive patients with ILD-ADM. Patients were classified into two categories, acute/subacute and chronic forms, according to the clinical presentation of ILD. The clinical features, responsiveness to therapy, and prognosis between the two forms were compared. Nine ILD-ADM patients were categorised as the acute/subacute form, and five as the chronic form. Arterial oxygen tension was significantly lower in the acute/subacute ILD than chronic ILD patients. On high-resolution computed tomography, ground-glass opacities were frequently found in the two forms, but consolidation was more common in acute/subacute ILD than chronic ILD. Bronchoalveolar lavage analysis showed higher numbers of total cells and lymphocytes in acute/subacute ILD than chronic ILD. Histologically, the most common finding was nonspecific interstitial pneumonia in the two forms, while diffuse alveolar damage was only found in acute/subacute ILD. Acute/subacute ILD was generally resistant to therapy, while chronic ILD responded well. Notably, the mortality of acute/subacute ILD was much higher than that of chronic ILD (67 versus 0%, respectively). In conclusion, interstitial lung disease associated with amyopathic dermatomyositis includes two different forms, the acute/subacute and chronic forms, with distinct prognoses.

Acute Disease↗
PubMed2006

Angle-resolved photoemission spectroscopy of the insulating NaxWO3: Anderson localization, polaron formation, and remnant Fermi surface.

The electronic structure of the insulating sodium tungsten bronze, Na(0.025)WO(3), is investigated by high-resolution angle-resolved photoemission spectroscopy. We find that near-E(F) states are localized due to the strong disorder arising from random distribution of Na+ ions in the WO(3) lattice, which makes the system insulating. The temperature dependence of photoemission spectra provides direct evidence for polaron formation. The remnant Fermi surface of the insulator is found to be the replica of the real Fermi surface in the metallic system.

Journal Article↗
PubMed2004

Minilaparotomy approach for colonic cancer: initial experience of 54 cases.

BACKGROUND: The early outcomes of minilaparotomy for resection of colonic cancer were evaluated. METHODS: In this study, 54 patients (34 Dukes' A, 15 Dukes' B, and 5 Dukes' C) successfully underwent curative resection of colonic cancer via minilaparotomy (skin incision, > or = 7 cm). The major exclusion criteria for this approach required a body mass index greater than 25 kg/m2, a tumor size exceeding 7 cm, a preoperative ileus, and tumor invading the adjacent organs. Patients (n = 54) who had undergone conventional open surgery before the introduction of this technique served as the control group by matching several clinicopathologic factors including body mass index. RESULTS: The passage of flatus (p < 0.01) and the beginning of oral intake (p = 0.02) were earlier, analgesic requirements were lower (p < 0.01), and postoperative serum C-reactive protein levels were lower in the minilaparotomy group (p < 0.01). The blood loss and frequency of postoperative complications did not differ between the groups. CONCLUSION: A minilaparotomy approach is a feasible, minimally invasive, and attractive alternative to conventional laparotomy for selected patients with colonic cancer.

Aged↗
PubMed2004

Influence of different pneumoperitoneal pressures on tumor cell distribution in rats.

BACKGROUND: The effect of different pneumoperitoneal pressures on tumor cell distribution was investigated. METHODS: Donryu rats were allocated to receive carbon dioxide pneumoperitoneum at 5, 10, or 15 mmHg for 60 min or to serve as a control. During the procedure, each rat was inoculated with radiolabeled ascites hepatoma cells via the portal vein (experiment 1) or femoral vein (experiment 2). In both experiments, the rats were killed 30, 60, 90, or 120 min after tumor cell inoculation, and the liver and lungs were extirpated for radioactivity count (n = 5 or 6 for each time point in each group). RESULTS: In experiment 1, the percentage of injected dose (% ID) for the liver was greater than for the other three groups 120 min after tumor cell inoculation. There were no significant differences in the %IDs of the lungs at any time point among the groups. In experiment 2, there were no significant differences in the %IDs of the liver and lungs at any time point among the groups. CONCLUSIONS: These results suggest that an elevated insufflation pressure facilitates the location of intraportally injected tumor cells in the liver, and that pulmonary location of the tumor cells may not depend on insufflation pressures in this animal model.

Animals↗
PubMed2004

Charge dynamics near the electron-correlation induced metal-insulator transition in pyrochlore-type molybdates.

The systematics of the bandwidth controlled metal-insulator transition (MIT) are investigated for R2Mo2O7 (R=Nd, Sm, Gd, Dy, and Ho) by measurements of dc and optical conductivity. The substantial role of electron correlation in driving the MIT is verified. With changing the R ionic radius (r) or equivalently the one-electron bandwidth, the T=0 K MIT occurs at rc approximately r(R=Gd). The T=0 K gap continuously vanishes as Delta proportional, variant(rc-r), while at the metallic side the decrease of Drude weight is followed towards rc. A high-temperature incoherent state is approached through crossover regions both from the metallic and the insulating state.

Journal Article↗
PubMed2003

Comparison of the effects of gasless procedure, CO2-pneumoperitoneum, and laparotomy on splenic and hepatic natural killer activity in a rat model.

BACKGROUND: Natural killer (NK) activity plays an important role in the prevention of tumor metastasis. However, few studies compared changes in NK activities between gas(less) laparoscopy and open surgery. MATERIALS AND METHODS: Donryu rats were randomized to 4 groups ( n = 6-9, for each lime point in each group): gasless group, pneumoperitoneum group, laparotomy group, and control group. The surgical treatment groups received additional cecal resection at the end of the procedures. Spleen cells and hepatic nonparenchymal cells were harvested at 6, 24, or 96 h, to determine the splenic and hepatic NK activities against YAC-1 cells. RESULTS: Compared with the anesthesia control, laparotomy and pneumoperitoneum depressed splenic NK activity at 24 h ( p < 0.01 for laparotomy and p < 0.05, for pneumoperitoneum) and 96 h ( p < 0.05). Laparotomy also depressed hepatic NK activity at 24 h ( p < 0.05). In contrast, the gasless procedure did not show any deterioration in the splenic and hepatic NK activities. CONCLUSION: These results suggest that gasless laparoscopic surgery would be a favorable approach in terms of the preservation of NK activities.

Animals↗
PubMed2003

Distribution of intrasplenically injected colon cancer cells following pneumoperitoneum in mice.

BACKGROUND: Few studies have examined tumor cell distribution following laparoscopic surgery for colorectal cancer. We examined the effect of carbon dioxide pneumoperitoneum on the distribution of intrasplenically injected colon cancer cells in mice. METHODS: Mice were intrasplenically injected with 2 x 10(4) colon 26 cells labeled with 111In-oxine and were randomized to undergo pneumoperitoneum at 10 mmHg for 30 min or to receive no treatment other than anesthesia. Radioactivity of the liver, lungs, and spleen was measured 30, 60, 90, or 150 min following tumor inoculation. RESULTS: The dynamic changes in the hepatic radioactivity were not similar between groups. However, the values were not significantly different at any time point. The radioactivity of lungs was extremely low in both groups throughout the experimental period. CONCLUSIONS: Pneumoperitoneum does not appear to cause the accumulation of intraportally spreading tumor cells in the liver, but it may affect the dynamic changes of tumor cells. Also, tumor cell localization in the lungs is negligible in both pneumoperitoneum and control groups.

Adenocarcinoma↗
PubMed2003

Oncological effects of insufflation with different gases and a gasless procedure in rats.

BACKGROUND: The validity of using carbon dioxide (CO2) pneumoperitoneum in laparoscopic tumor surgery has not been investigated thoroughly. The oncologic effects of a gasless procedure and insufflation with different gases were compared in rats. METHODS: In all the experiments, Donryu rats were randomized to receive a gasless procedure; to receive insufflation with CO2, helium, or air at 10 mmHg for 30 min, or to serve as control subjects without insufflation. In experiment 1, involving 60 rats, ascites hepatoma AH130 cells were inoculated intraperitoneally just before the procedures. The S-phase fraction of the intraperitoneal tumor cells was determined using a flow cytometry on day 7. In experiment 2, 60 rats injected intraperitoneally with latex particles received one of the procedures. At the end of the procedure, peritoneal macrophages were harvested to determine the number of phagocytosed particles. In experiment 3, 75 rats inoculated intraperitoneally with AH130 cells received one of the procedures for 5 consecutive days and were followed for survival analysis. RESULTS: EXPERIMENT 1: The S-phase fraction was lower after insufflation with air or helium (p < 0.01) than with the anesthesia control condition. Insufflation with CO2 showed a higher S-phase fraction than the gasless procedure or insufflation with air or helium (p < 0.01). EXPERIMENT 2: The phagocytotic activity of peritoneal macrophages was increased by insufflation with helium and air, as compared with the control condition (p < 0.01). Insufflation with CO2 deteriorated the phagocytotic activity more than the gasless procedure (p < 0.05) or insufflation with air or helium (p < 0.001). EXPERIMENT 3: Insufflation with gases demonstrated shorter survival than the anesthesia control condition or the gasless procedure regardless of the gases used (p < 0.01). CONCLUSIONS: These results suggest that the choice of gases may affect the proliferation of tumor cells and the phagocytotic activity of peritoneal macrophages, insufflation itself may promote tumor spread regardless of the gases used, and the gasless procedure may be oncologically advantageous in this animal model.

Air↗
PubMed2003

Gasless laparoscopic surgery for ulcerative colitis and familial adenomatous polyposis:initial experience of 7 cases.

PURPOSE: We evaluated the data on initial experience of gasless laparoscopic surgery for patients with ulcerative colitis (UC) and familial adenomatous polyposis (FAP). PATIENTS AND METHODS: Seven patients (male/female = 3:4, median age 23, UC/FAP=5:2) underwent gasless laparoscopic total (procto) colectomy. Our basic surgical procedure involved (1) a 6- to 8-cm incision made at the beginning of the operation, (2) the wound pulled upward and/or laterally by retractors, and (3) conventional surgical instruments used through the wound; occasionally laparoscopic assistance and abdominal lifting were employed. The results were compared to those of 7 patients who had undergone conventional open surgery. RESULTS: Oral intake started earlier (p = 0.03) and C-reactive protein level on POD 4 was lower (p = 0.03) in the gasless group than in the control group. Duration of surgery, blood loss, requirement of analgesia, and morbidity rate were not significantly different between the groups. CONCLUSION: Our preliminary results suggest that gasless laparoscopic surgery for UC and FAP is feasible and can be an alternative method for minimally invasive surgery.

Adenomatous Polyposis Coli↗
PubMed2002

Induction of vasculogenesis in breast cancer models.

Recently, there have been reports of postnatal vasculogenesis in cases of ischaemia models. The aim of the present study is to provide evidence of postnatal vasculogenesis in breast-cancer-bearing mice. Based on cell surface antigen expression, we isolated endothelial precursor cells from bone marrow, peripheral blood and tumour-infiltrating cells from mice that had received six human breast cancer xenografts. In all three areas (bone marrow, peripheral blood and tumour-infiltrating cells), endothelial precursor cell population was elevated in all transplanted mice. Differentiation and migration activities of endothelial precursor cells were measured by comparing levels of the endothelial precursor cell maturation markers Flk-1, Flt-1, Tie2, VE-cadherin and CD31 among these three areas. The endothelial precursor cell population was 14% or greater in the gated lymphocyte-size fraction of the inflammatory breast cancer xenograft named WIBC-9, which exhibits a hypervascular structure and de novo formation of vascular channels, namely vasculogenic mimicry (Shirakawa et al, 2001). In vitro, bone marrow-derived endothelial precursor cells from four human breast cancer xenografts proliferated and formed multiple clusters of spindle-shaped attaching cells on a vitronectin-coated dish. The attaching cells, which incorporated DiI-labelled acetylated low-density lipoprotein (DiI-acLDL) and were negative for Mac-1. The putative bone marrow derived endothelial precursor cell subset, which was double positive of CD34 and Flk-1, and comparative bone marrow derived CD34 positive with Flk-1 negative subset were cultured. The former subset incorporated DiI-acLDL and were integrated with HUVECs. Furthermore, they demonstrated significantly higher levels of murine vascular endothelial growth factor and interleukin-8 in culture supernatant on time course by enzyme-linked immunosorbent assay. These findings constitute direct evidence that breast cancer induces postnatal vasculogenesis in vivo.

Animals↗
PubMed2002

Fournier's gangrene after unrelated cord blood stem cell transplantation.

A 16-year-old boy with refractory acute myelogenous leukemia developed Fournier's gangrene as an early complication after two-antigen HLA-mismatched unrelated cord blood stem cell transplantation. On day 25 after the transplantation, he noted abrupt onset of penile swelling with miction pain. The penile inflammation rapidly extended posteriorly to involve the scrotum and perianal tissues, inferiorly to involve the thighs, and superiorly up the lower abdominal region within the next 36 h, and he died from sepsis on day 27. Fournier's gangrene presenting as a genitoperineal necrotizing fasciitis should be considered as a potential complication in umbilical-cord blood recipients in the cytopenic post-transplant phase.

Adolescent↗
PubMed2001

Increased insufflation pressure enhances the development of liver metastasis in a mouse laparoscopy model: possible mechanisms.

BACKGROUND: The effect of different insufflation pressures and durations of CO2 pneumoperitoneum on the growth of liver metastasis was investigated in a mouse model. The possible mechanisms involved in the pressure-related enhancement of liver metastasis were also examined. METHODS: Mice inoculated intraportally with colon 26 cells underwent CO2 pneumoperitoneum at different pressures (5,10, or 15 mmHg) for 30 or 60 min, or received no treatment other than tumor cell inoculation (control). The subsequent growth of liver metastases was examined. Mice injected intraportally with 111In-oxine-labeled colon 26 cells underwent pneumoperitoneum at three different pressures or served as controls. The radioactivity of the liver was determined to evaluate tumor accumulation in the liver. Mice received pneumoperitoneum at three different pressures or received trocar placement alone. Changes in plasma interleukin-6 levels were determined. RESULTS: The growth of liver metastases on day 14 was influenced by increased insufflation pressures (p < 0.05) rather than the prolonged duration of pneumoperitoneum without significant interaction. The 15-mmHg pneumoperitoneum group showed a higher (p < 0.05) accumulation of radioactivity in the liver compared with the 5-mmHg pneumoperitoneum group and controls. Pneumoperitoneum groups with 5 and 10 mmHg showed higher (p < 0.05) peak levels of IL-6 compared with controls. CONCLUSIONS: An elevated insufflation pressure plays an important role in the enhancement of liver metastases, and this pressure-related adverse effect may be partly relevant to facilitating accumulation of tumor cells in the liver.

Animals↗
PubMed2001

Matrix metalloproteinase-2 and -9 in bile as a marker of liver metastasis in colorectal cancer.

Matrix metallproteinases (MMP)-2 and -9 are associated with cancer invasion and metastasis. MMP-2 and MMP-9 activities have never been assayed in bile. In the present study we investigated whether MMP-2 and -9 activities in the bile could be a marker for evaluation of liver metastasis in colorectal cancer. Fifty-three patients underwent colorectal resection for histologically verified adenocarcinoma. Twenty-six patients had colorectal cancer without liver metastasis and 27 patients had metastatic liver tumor. Six patients were studied as carcinoma-free control. MMP-2 and MMP-9 activities were assayed in bile using gelatin zymography and quantitated. Active MMP-2 activity of colorectal cancer with liver metastasis group (24.1 +/- 2.5 pixel count) was significantly higher than that of colorectal cancer without liver metastasis group (11.4 +/- 1.3 pixel count) (P < 0.001) or of control group (6.4 +/- 1.0 pixel count) (P < 0.001). Active MMP-9 was not detected in bile. ProMMP-9 activity of colorectal cancer with liver metastasis group (530.3 +/- 127.5 pixel count) was significantly higher than that of colorectal cancer without liver metastasis group (213.9 +/- 33.2 pixel count) (P = 0.008). This is the first report showing that the levels of active MMP-2 and proMMP-9 in bile were significantly higher in liver metastasis of colorectal cancer than in metastasis-free colorectal cancer. The results suggest that activities of active MMP-2 and proMMP-9 in the bile may be useful markers for predicting liver metastasis in colorectal cancer.

Adenocarcinoma↗
PubMed2001

Liver metastases are less established after gasless laparoscopy than after carbon dioxide pneumoperitoneum and laparotomy in a mouse model.

BACKGROUND: Although the liver is the most frequent site of cancer recurrence after conventional open surgery for colorectal cancer, the effect of laparoscopic procedures with or without gas insufflation on the development of liver metastases is largely unknown. METHODS: Male BALB/C mice inoculated intraportally with colon 26 cells were randomized to undergo carbon dioxide pneumoperitoneum (n = 14), abdominal wall lifting (n = 14), or full laparotomy (n = 12), or to serve as control subjects without any procedures other than tumor inoculation (n = 13). RESULTS: The growth of liver metastases 14 days after surgery was enhanced after full laparotomy (p < 0.01) and pneumoperitoneum (p = 0.02), as compared with that in the control subjects, whereas there was no difference in the growth of liver metastases between abdominal wall lifting and the control condition (p = 0.99). CONCLUSIONS: These results suggest that the defense against liver metastasis is better preserved after the gasless procedure than after laparotomy and carbon dioxide pneumoperitoneum in the reported animal model.

Animals↗
PubMed2001

Dose-finding phase I study of simultaneous weekly infusion with doxorubicin and docetaxel in patients with advanced breast cancer.

BACKGROUND: Combination therapy with doxorubicin (DOX) and docetaxel (DOC), given 3 weeks apart, is one of the standard regimens used for treating metastatic breast cancer, but it frequently generates febrile neutropenia. To find a safer regimen with less myelotoxicity and the appropriate dose intensity, we conducted a phase I study of simultaneous weekly infusion with DOX and DOC. METHODS: Twenty-five patients with advanced breast cancer were treated with an intravenous push-injection of DOX that was immediately followed by a 1-h infusion of DOC. This was repeated every week for at least 6 weeks. The premedication employed was three 4-mg doses of dexamethasone every week. Patients were divided into four groups for which the doses of DOX and DOC were escalated in 5-mg/m2 increments. RESULTS: In the 18 patients who were treated with DOX 15 or 20 mg/m2 and DOC 25 mg/m2, or lower, the regimen was found to be tolerable, without febrile episodes. The regimen with 20 mg/m2 of DOX and 30 mg/m2 of DOC was the maximum tolerated dose. Other indications of grade 3 toxicity included asthenia in 4% of patients, anorexia in 8%, and vomiting in 8%. Of the 25 patients, 14 had a partial response. The overall response rate was 56% (95% confidence interval [CI], 35% to 77%). The recommended dose for further trial was 20 mg/m2 of DOX and 25 mg/m2 of DOC. CONCLUSION: Simultaneous weekly infusion with DOX and DOC was feasible, with modest neutropenia and preserved dose intensity. This regimen may be helpful in the management of patients with advanced breast cancer.

Adult↗
PubMed2001

Liver metastasis following pneumoperitoneum with different gases in a mouse model.

BACKGROUND: The validity of using CO2 in laparoscopic tumor surgery has not yet been established. To address this question, we investigated the growth of liver metastases following insufflation with different gases in a mouse laparoscopy model. METHODS: Male BALB/C mice inoculated intraportally with colon 26 cells were randomized to undergo pneumoperitoneum with CO2 (n = 16), helium (n = 16), argon (n = 16), or air (n = 17), or to act as controls without insufflation (n = 17). RESULTS: The growth of cancer nodules on the liver 14 days after surgery was greater in mice following insufflation with CO2 (p < 0.01), helium (p < 0.01), argon (p = 0.01), and air (p = 0.07) than in control mice. No significant differences were found between the four insufflation groups in the growth of liver metastases. CONCLUSION: These results suggest that insufflation plays an important role in the development of liver metastases but that the choice of gas may not affect their growth.

Analysis of Variance↗
PubMed2001

Impact of oral antimicrobial prophylaxis on surgical site infection and methicillin-resistant Staphylococcus aureus infection after elective colorectal surgery. Results of a prospective randomized trial.

The impact of oral antimicrobial prophylaxis on the surgical site infection and methicillin-resistant Staphylococcus aureus (MRSA) infection after elective colorectal surgery was evaluated by a prospective randomized single-blind study. The patients were randomly allocated to receive either mechanical bowel cleansing with polyethylene glycol alone (group 1) or mechanical cleansing plus oral antimicrobial prophylaxis with kanamycin and erythromycin for 2 days prior to surgery (group 2). In both groups, cefotiam was intravenously given twice a day for 3 days. A total of 143 patients (71 for group 1 and 72 for group 2) were eligible. The incidence of a surgical site infection was 23.9% in group 1 and 11.1% in group 2 (P = 0.04). The incidence of MRSA infection including at surgical and remote sites was 11.1% in group 1 and 5.6% in group 2 (P = 0.19). A multivariate logistic regression analysis showed that the risk of surgical site infection was influenced by the choice of the chemical bowel preparation (P = 0.03) and blood loss (P < 0.01), while an MRSA infection was predominantly influenced by blood loss (P < 0.01) followed by coexisting underlying diseases (P = 0.07). These results suggest that preoperative antimicrobial prophylaxis would be useful for reducing the incidence of a surgical site infection without increasing the risk of an MRSA infection following elective colorectal surgery.

Adult↗