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Yosuke Adachi

Publications and source records attributed to Yosuke Adachi.

At least 19 recordsLinked to original sources
PubMed2006

Diffusive separation of the lower atmosphere.

The separation of atmospheric constituents by gravity has been proposed theoretically for almost two centuries. However, turbulent mixing has prevented the detection of this phenomenon in the lower atmosphere. By using precise measurements of the Ar/N2 ratio of air samples taken under strong nocturnal inversions, we have detected such separation in near-surface layers. The effect is shown to be consistent with combined influence of thermal and gravimetric separation, with the thermal contribution being more important.

Journal Article↗
PubMed2006

Length of laparotomy incision and surgical stress assessed by serum IL-6 level.

BACKGROUND: Because surgical stress is thought to have an effect on morbidity, mortality, and remnant tumour progression after surgery, diminishing surgical stress is important. The purpose of this study was to assess in a murine model whether the length and type of laparotomy incision influence surgical stress. METHODS: Serum IL-6 concentrations were measured sequentionally in 220 male BALB/c mice who were assigned to different basic laparotomies, (1-cm versus 2-cm versus 3-cm laparotomy with or without caecal resection), other types of laparotomy (3-cm, 1-cm x 3, 3-cm transverse, 3-cm laparotomy with rapid closure), or 3-cm skin incision with or without laparotomy. The serum level of IL-6 was measured by ELISA. RESULTS: Serum IL-6 levels at 3 and 6h after surgery were significantly higher in the 3-cm laparotomy group (1,680+/-802pg/ml and 1,066+/-507pg/ml, respectively), than in the 1-cm laparotomy group (797+/-427pg/ml and 515+/-212pg/ml, respectively). When caecal resection was added, the serum IL-6 level at 6h was significantly higher in the 3-cm laparotomy group (2,844+/-134pg/ml) than in the 1-cm laparotomy group (2,200+/-379pg/ml). Although the type of laparotomy incision was not associated with the serum level of IL-6, the serum IL-6 level after midline skin incision without laparotomy (245+/-142pg/ml) was significantly lower than that after 3-cm laparotomy (1,680+/-802pg/ml). CONCLUSIONS: The length of laparotomy incision was correlated with the serum level of IL-6 in a murine model. The surgical stress related to abdominal procedures might be decreased when laparotomy wounds are kept as small as possible.

Animals↗
PubMed2006

Expression of vascular endothelial growth factor receptors is closely related to the histological grade of hepatocellular carcinoma.

Angiogenesis is important for tumor growth, and is regulated by angiogenetic factors such as vascular endothelial growth factor (VEGF). In the present study, we investigated whether or not expression of VEGF receptors (VEGFRs) is related to the proliferation of tumor cells in hepatocellular carcinoma (HCC). We simultaneously stained proliferation marker Ki-67 antigen and either VEGFR1 (Flt-1) or VEGFR2 (Flk-1) on paraffin-embedded tissue sections from 50 cases of surgically resected human HCC. Based on the staining pattern of VEGFRs, we classified the cases into 4 categories; receptor double-negative, Flt-1 single-positive, Flk-1 single-positive, receptor double-positive. Interestingly, the Ki-67 index was significantly lower in receptor double-negative cases in comparison to that in either Flt-1 single-positive or Flk-1 single-positive cases (P = 0.0491, P = 0.0196, respectively). Moreover, the index was also significantly lower in receptor double-positive cases in comparison to either Flt-1 single-positive or Flk-1 single-positive cases (P = 0.0026, P < 0.0001, respectively). We further investigated 35 cases showing a Ki67 index > 10% to determine the expression of VEGFRs on Ki-67 antigen-positive proliferating cells. Surprisingly, the histological grade of HCC and the expression pattern of VEGFRs showed a characteristic relation; the well-differentiated HCC cases were all distributed in the Flk-1-positive group (7/7), moderately differentiated HCC cases were distributed in either the Flt-1 or Flk-1 single-positive group (20/21), and poorly differentiated HCC cases were predominantly distributed in either the receptor double-negative or double-positive group (6/7). These findings suggest that the expression pattern of VEGFRs influences the histological differentiation of HCC.

Aged↗
PubMed2005

Adenocarcinoma in bladder diverticulum, metastatic from gastric cancer.

BACKGROUND: Metastasis to the urinary bladder from gastric cancer is rare. Metastasis to a diverticulum of the bladder from gastric cancer is extremely rare. We report a case of isolated bladder metastasis from gastric cancer and invasion localized to the muscularis propria of the primary site (stomach). CASE PRESENTATION: A 90-year-old female presented with nausea and vomiting that was diagnosed as gastric cancer, the patient also had intermittent hematuria. Pelvic computed tomography identified an abnormally thickened area in the bladder wall that was diagnosed as a diverticulum of the bladder. A biopsy of the bladder wall revealed well differentiated tubular adenocarcinoma metastatic from gastric carcinoma. CONCLUSION: Almost all cases of bladder metastasis from gastric cancer had peritoneal dissemination. This particular presentation of bladder metastasis from gastric cancer, to the best of our knowledge, has not been previously reported.

Journal Article↗
PubMed2005

Identification of an immune tolerance reaction in response to pretreatment with frozen pancreatic tissue in islet cell transplantation in rats.

OBJECTIVES: Whereas transplantation of insulin-secreting pancreatic islets may provide long-term control of glucose metabolism in patients with diabetes mellitus, transplant rejection remains a problem. In this study, we tried pretreatment with frozen pancreatic tissue in a rat model of islet cell transplantation to determine whether induction of immune tolerance is feasible. METHODS: Isolated islet cells from Wistar rats were transplanted into the spleen of recipient rats that were sensitized and rats that were not sensitized with frozen pancreatic tissue. Spleens were analyzed histologically and then examined immunohistochemically for expression of insulin, a pancreas-specific gene. With the use of cDNA primers for proinsulin, RT-PCR was performed to detect islet cells in the spleen. RESULTS: Although islet cells were present in spleens at posttransplantation day (PTD) 1, islet cell clusters in recipients without pretreatment were markedly destroyed on PTD 14 on histologic examination. In contrast, islet cell clusters in recipients sensitized with frozen pancreatic tissue appeared similar to those at PTD 1 even at PTD 14. Proinsulin gene expression was found to be specific to pancreatic tissue. In recipients sensitized with frozen pancreatic tissue, proinsulin gene expression was identified in recipient spleens, even at PTD 14, whereas it was undetected in the absence of pretreatment. In recipients transplanted with islet cells and treated simultaneously with frozen pancreatic tissue, proinsulin gene expression was completely eliminated. The immunohistologic study also showed the presence of insulin-producing islet cells in the spleens of rats sensitized with frozen pancreatic tissue. CONCLUSIONS: Inhibition of the immune reaction in transplant rejection may be mediated by pretreatment with frozen donor tissue.

Animals↗
PubMed2003

Less impaired cell-mediated immune response in the murine peritoneal cavity after CO(2) pneumoperitoneum.

PURPOSE: We compared changes in the populations of peritoneal T lymphocytes and natural killer (NK) cells after CO(2) pneumoperitoneum and laparotomy to clarify whether pneumoperitoneum affects cell-mediated immune responses in the peritoneal cavity. METHODS: We analyzed and compared populations of T lymphocytes and NK cells among peritoneal exudative cells (PECs) collected from 185 female mice subjected to pneumoperitoneum, laparotomy, or anesthesia only. PECs were collected postoperatively, and the populations of T lymphocytes and NK cell subsets were analyzed by flow cytometry. The NK cell cytotoxicity (NKCC) of PECs and splenocytes was measured. RESULTS: The populations of CD3(+), CD4(+), and CD8(+) lymphocytes in the PECs continued to increase up until postoperative day (POD) 7 after laparotomy. The CD4/8 ratio on POD 3 was significantly lower after laparotomy than after pneumoperitoneum. The percentages of NK cells in the pneumoperitoneum group were significantly lower than those in the laparotomy group. On POD 1, the NKCC of splenocytes was less impaired in the pneumoperitoneum group than in the laparotomy group (10.3% vs 5.0%, P << 0.05). CONCLUSION: Laparoscopic surgery is preferable to open surgery because it results in less impairment of systemic and intraperitoneal cell-mediated immune responses.

Animals↗
PubMed2003

AFP-producing gastric carcinoma: multivariate analysis of prognostic factors in 270 patients.

Serum alpha-fetoprotein (AFP) is sometimes high in patients with primary gastric carcinoma, and there is no comprehensive study on the clinicopathologic characteristics and prognostic factors of AFP-producing gastric carcinoma (AGC). To clarify the variables associated with the survival after gastrectomy for AGC, we reviewed the data of patients with AGC and examined the independent prognostic factors. We studied 270 cases of AGC reported in the Japanese literature from June 1982 to March 2001, together with 1 patient of our own experience. The clinicopathologic findings, including serum AFP level, operative curability, and stage of the disease were examined, and factors associated with survival were determined by multivariate analysis. There were 15 stage I tumors (6%), 50 stage II tumors (19%), 51 stage III tumors (20%), and 145 stage IV tumors (55%). The tumors were characterized by frequent serosal invasion (75%), lymph node metastasis (83%), liver metastasis (33%), stage III or IV disease (75%), and noncurative operation (48%). The survival was influenced by the serum AFP level, tumor size, serosal invasion, lymph node metastasis, and liver metastasis, but the independent prognostic factors were operative curability (curative vs. noncurative) and stage of the disease (I, II vs. III, IV). Although the 5-year survival rate and median survival period in all patients were 22% and 14 months, respectively, those in patients with curative gastrectomy were 42% and 29 months, respectively. The results indicate that operative curability and stage of the disease are factors associated with the survival of patients with AGC. Although tumors are often advanced and complicated with liver metastases, long-term survival can be achieved when patients with stage I or II tumor undergo curative gastrectomy.

Biomarkers, Tumor↗
PubMed2002

Clinical outcome of proximal versus total gastrectomy for proximal gastric cancer.

Tumors in the upper one-third of the stomach has been increasing. Although the standard operation for proximal gastric cancer has been total gastrectomy, some have used proximal gastrectomy reconstructed by jejunum or gastric tube. The aim of this study was to evaluate the surgical results, hospital costs, and quality of life after gastrectomy for cancer. A consecutive series of 51 patients with stage I or II proximal gastric cancer was studied: 14 underwent proximal gastrectomy reconstructed by gastric tube (direct anastomosis between esophagus and remnant of tube-like stomach), 17 proximal gastrectomy reconstructed by jejunum, and 20 total gastrectomy in Roux-en-Y fashion. Quality of life was estimated by a 24-item questionnaire with a scoring system of 1 to 3, and hospital costs covered all charges during the hospital stay. Operating time, blood loss, and hospital stay for the gastric tube group were less than those for the jejunum group or the total gastrectomy group. Hospital charges for the gastric tube group were lower than those for the jejunum group or the total gastrectomy group (141 x 10 4 yen, 179 x 10 4 yen, 211 x 10 4 yen, respectively). Although the total score for quality of life was not significantly different among the three groups (35.9, 39.5, 37.6), the number of meals per day was less and the performance status was better in the gastric tube group. Jejunal interposition was less favorably accepted by the patients as a good operation they would recommend to others. The results indicate that, in patients with proximal gastric cancer, proximal gastrectomy reconstructed by gastric tube provides a shorter operating time, earlier recovery, lower hospital charge, and better performance status when compared with proximal gastrectomy reconstructed with jejunum or total gastrectomy.

Aged↗
PubMed2002

Superficially spreading cancer of the stomach.

BACKGROUND: Superficially spreading cancer (SSC) of the stomach is rare and extends widely along the mucosa or submucosa of the stomach. This study was conducted to clarify the clinicopathologic characteristics and prognosis of patients with SSC. METHODS: SSC was defined as a tumor invading the mucosa or submucosa and measuring > or =5 cm in size. The clinicopathologic findings and outcomes of 36 patients with SSC were compared with those of 300 patients with early gastric cancer (EGC) measuring < or =5 cm and 271 with advanced gastric cancer measuring > or =5 cm. RESULTS: SSC was significantly different from ordinary EGC in tumor size, frequency of lymph node metastasis, lymphatic invasion, venous invasion, and stage II, III, and IV disease. The frequency of serosal invasion, lymph node metastasis, and lymphatic and venous invasions in cases of SSC was significantly lower than with advanced gastric cancer. Although tumor size of SSC evaluated before operation was smaller than that on the resected specimen, the 10-year survival rate was not different between SSC and ordinary EGC. CONCLUSIONS: SSC was characterized by high frequency of lymph node metastasis and preoperative underestimation of tumor size. SSC should be treated by a gastrectomy and lymphadenectomy with sufficient resection margin.

Aged↗
PubMed2002

Prognostic effect of lymph node micrometastasis in patients with histologically node-negative gastric cancer.

BACKGROUND: There is no consensus as to the impact of lymph node micrometastasis on survival of patients with gastric cancer. The aim of this study was to clarify the prognostic significance of lymph node micrometastasis in patients with histologically node-negative gastric cancer. METHODS: Lymph nodes (n = 2039) from 64 patients with histologically node-negative gastric cancer (T2, T3) were evaluated for micrometastasis. Three serial 5- micro m sections of the resected lymph nodes were prepared for immunohistochemical staining with the anti-cytokeratin antibody CAM 5.2. RESULTS: Micrometastasis was found in 73 of 2039 nodes (4%) and 20 of 64 patients (32%). The 5-year survival rate was significantly lower for patients with lymph node micrometastasis than for those without lymph node micrometastasis (66% vs. 95%, P <.01). The 5-year survival rate was significantly lower when there were four or more positive micrometastatic nodes (94% vs. 29%, P <.01) and when there were extragastric micrometastatic nodes (89% vs. 53%, P <.01). CONCLUSIONS: Lymph node micrometastasis was associated with poor outcome in patients with histologically node-negative gastric cancer. The number and the level of lymph node micrometastases are useful prognostic markers for deciding treatment strategies for additional therapy and follow-up.

Adenocarcinoma↗
PubMed2002

A randomized controlled trial comparing open vs laparoscopy-assisted distal gastrectomy for the treatment of early gastric cancer: an interim report.

BACKGROUND: The application of laparoscopy-assisted distal gastrectomy (LADG) for early gastric cancer remains controversial among gastric surgeons. The purpose of this study was to compare LADG with open distal gastrectomy (ODG) regarding clinical outcome and postoperative parameters, including postoperative pain and pulmonary function. METHODS: From October 1998 to March 2001, 28 patients with early gastric cancer were randomly assigned to an LADG (n = 14) or ODG group (n = 14) with Billroth I reconstruction. Postoperative pain during resting, coughing, and walking were evaluated by a visual analog scale (VAS). Pulmonary functions such as forced vital capacity (FVC) and forced expiratory volume in 1 second (FEV1) measured on the third postoperative day were compared with preoperative functions. RESULTS: Patients in the 2 groups were comparable for age, gender, height, weight, staging, and location of gastric cancer. The mean blood loss was significantly less in the LADG than in the ODG group (P <.05). Histologic examinations of resected specimens revealed that these 2 operations were identical from the standpoint of curability. Patients in the LADG group recovered both bowel movement and walking ability earlier than did patients in the ODG group (P <.05). The postoperative VAS pain score during rest was lower for 3 days after LADG than ODG (P <.05) and for 1 day during coughing or walking (P <.05). The pulmonary functions such as FVC and FEV1 values were reduced on the third day after LADG and ODG. However, the FVC value on the third day after LADG was lower than after ODG (P <.05). CONCLUSIONS: This study demonstrates that LADG has several advantages including an earlier recovery, less pain, and less impaired pulmonary function after gastric surgery when compared with ODG; furthermore, no reduction in curability was observed.

Aged↗
PubMed2002

Laparoscopy-assisted Billroth-I gastrectomy (LADG) for cancer: our 10 years' experience.

To evaluate laparoscopy-assisted Billroth-I gastrectomy (LADG), we examined the outcome of its use over the last 10 years. From December 1991 to December 2001, 116 patients with early gastric cancer underwent LADG in the surgical department of Oita Medical University and Koga hospital by the same surgical staffs. An operation record and clinical sheets were reviewed to obtain the operative findings, clinical course, and pathologic findings of resected specimens to evaluate the usefulness of LADG in the management of early gastric cancer. In all LADG procedures, regional lymph nodes dissection (D1+alpha) was successfully performed using laparoscopy. The mean operative duration and blood loss were 234 minutes and 139 mL, respectively. There were only four major complications, including pneumonia, leakage of anastomosis, pancreatic injury, and anastomotic stenosis, but all these cases were successfully treated conservatively. The mean length of postoperative stay was 16.3 +/- 2.5 days. All patients except one, who died not of cancer but of cerebral bleeding, were alive without recurrence or port-site metastasis during mean follow-up period of 45 months. We successfully performed 116 LADG procedures over 10 years. This procedure is recommended for the treatment of patients with early gastric cancer because of the associated good prognosis and several benefits, including less invasiveness and early recovery.

Adult↗
PubMed2002

Modern treatment of early gastric cancer: review of the Japanese experience.

BACKGROUND: Recently, detections of early gastric cancer (EGC) have been increasing, and the treatment strategies for gastric cancer have been changing. To demonstrate recent clinical experience of EGC in Japan and to assess modern strategies for the treatment of EGC, we investigated the English-language literature of the past 10 years through computer searches. METHODS: This article intends to provide gastric surgeons with recent Japanese experience of the treatment for EGC. In a search for modern treatments of EGC, we selected 100 papers published in well-known medical journals, and focused on the following items of EGC: (1) prognostic factors, (2) endoscopic treatment, (3) surgical procedures, and (4) Japanese guidelines. RESULTS: The most important factor influencing the survival of patients with EGC is the status of lymph node metastasis. The incidence of lymph node metastasis is 1-3% for mucosal cancers and 11-20% for submucosal cancers. Endoscopic mucosal resection (EMR) is a technique for the treatment of EGC, and the recent indication includes the tumors confined to the mucosa up to 3 cm in size or those invading the superficial submucosa. Surgical procedures include conventional Billroth I gastrectomy, limited resections, and laparoscopic surgery. Laparoscopic wedge resection using the lesion-lifting method and laparoscopy-assisted distal gastrectomy provide less pain, faster recovery and shorter hospital stay. Guidelines for the treatment of gastric cancer proposed by the Japanese Gastric Cancer Association show that patients with mucosal cancer can be managed by EMR or distal gastrectomy, whereas patients with submucosal cancer are candidates for distal gastrectomy with lymph node dissection. CONCLUSION: Although the prognosis of patients with EGC depends on the presence or absence of lymph node metastasis, most are successfully treated by modern endoscopic or surgical techniques. Laparoscopic surgery and limited resections will contribute to the better quality of life of patients with EGC.

Biopsy, Needle↗
PubMed2000

Papillary adenocarcinoma of the stomach.

BACKGROUND: Papillary gastric carcinoma (PGC) is a rare histologic entity among gastric adenocarcinomas. The aim of this study was to clarify the clinicopathologic characteristics of PGC, including the survival rate, recurrence pattern, and factors influencing the prognosis of patients with PGC.METHODS: The clinicopathologic findings of 65 patients with PGC and 566 patients with non-papillary gastric carcinoma (NGC) were examined and compared. The tumor was classified as PGC when more than 50% of the tumor area contained papillary structures. Survival rates were calculated using the Kaplan-Meier method and were assessed by the generalized Wilcoxon test. Prognostic factors were evaluated by univariate analysis, using the chi(2) test and Student's t-test, and confirmed by multivariate analysis, using the Cox proportional hazards model.RESULTS: PGC was characteristically found in patients over 65 years of age (68%), was located in the upper one-third of the stomach (37%), was of grossly localized type (85%), was negative for serosal invasion (86%), and was associated with liver metastasis (14%). The overall 5-year survival rate for patients with PGC was significantly lower than the rate for those with NGC (63% vs 76%) ( P < 0.05). Although the 5-year survival rate for each stage of PGC and NGC did not differ significantly, the death of PGC patients was more frequently associated with liver metastasis (62%) than with peritoneal dissemination (5%). Independent prognostic factors of PGC were liver metastasis, serosal invasion, and lymph node metastasis.CONCLUSION: These results suggest that PGC is characterized by advanced patient age, proximal tumor location, grossly localized type, negative serosal invasion, and frequent liver metastasis. A poor prognosis for patients with PGC is associated with the presence or recurrence of liver metastasis.

Journal Article↗