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T Tajiri

Publications and source records attributed to T Tajiri.

At least 55 records · Page 3Linked to original sources
PubMed2000

Severity of trauma changes expression of TNF-alpha mRNA in the brain of mice.

BACKGROUND: The greater nitrogen loss that occurs with increasing severity of trauma is believed to occur because activation of the hypothalamus-pituitary axis is greater with severe injury. Cytokines in the brain stimulate the hypothalamus-pituitary-adrenal axis. This study was carried out to investigate whether the brain would recognize severity of trauma via TNF-alpha mRNA synthesis in the brain. METHODS: Male C57BL/6 mice (n = 70, BW: 20-28 g) were randomly assigned into four groups, (1) control (no anesthesia or incision), (2) anesthesia alone, (3) anesthesia plus laparotomy by short incision (short), and (4) anesthesia plus laparotomy by long incision (long). A laparotomy was carried out in the short and long groups by a 1.2-cm vertical incision and by a horizontal plus a vertical incision (2.4 x 2.4 cm), respectively. Exactly either 3 or 24 h after surgery, the animals were decapitated. TNF-alpha mRNA levels in the tissues were determined by semi-quantitative PCR. RESULTS: Nitrogen and catecholamine excretion were increased in the long wound group compared with the short wound group. Expression of TNF-alpha mRNA in the brain was greater in the long group after surgery than in the control, anesthesia, and short groups (brain, long: 0.150 +/- 0.005; P < 0.01 vs control, anesthesia alone, and short groups), but TNF-alpha levels in the plasma were the same in the short and long groups after surgery. CONCLUSION: Levels of TNF-alpha mRNA in the brain were enhanced according to the length of the wound probably because of greater neural stimuli from the wound site, and this elevation was involved in the greater nitrogen loss.

Actins↗
PubMed2000

Administration of opiate receptor antagonist inhibits mucosal atrophy of the gut in fasting rats.

OBJECTIVE: The objective of this study was to determine whether the opiate mu receptor antagonist naloxone would prevent atrophy of the gut in 24-h-fasted rats. METHODS: Male Sprague-Dawley rats (n = 76, body weight 200-225 g) were catheterized in the jugular vein on Day 0. The rats were fed standard rat chow for 4 days. On Day 4, the diet was changed to the standard liquid diet, and the rats were allowed free access to the liquid diet. On Day 7, the rats were randomized into five groups: (1) free fed, (2) free fed plus naloxone, (3) pair fed, (4) fasting, (5) free fed plus morphine, (6) fasting plus naloxone. Either naloxone (0.16 mg/kg/h) or morphine (0. 21 mg/kg/h) was continuously infused via venous catheter for 24 h. On Day 8, 24 h after fasting or free feeding, the animals were sacrificed. RESULTS: Twenty-four hours of fasting caused atrophy of the jejunum and elevated morphine levels in the brain (free fed, 931. 3 +/- 122.3 fmol/g, vs fasting, 1419.0 +/- 150.0, P < 0.05). Morphine infusion reduced villus height, mucosal weight, and protein content in jejunum as compared with the free fed rats receiving saline. Administration of naloxone caused an increase in villus height (fasting, 587.0 +/- 25.8 microm, vs fasting plus naloxone, 670.0 +/- 17.4, P < 0.05), mucosal weight (fasting, 17.4 +/- 1.8 mg/cm, vs fasting plus naloxone, 22.6 +/- 1.9, P < 0.05), and protein content (fasting, 13.5 +/- 0.7 microg/cm, vs fasting plus naloxone, 16.7 +/- 0.6, P < 0.05) in jejunum. CONCLUSION: Mucosal atrophy of the jejunum is caused by endogenous opioid in fasting rats.

Animals↗
PubMed2000

Effect of surgical stress on endogenous morphine and cytokine levels in the plasma after laparoscopoic or open cholecystectomy.

BACKGROUND: Endogenous morphine in the brain leads to various biological responses after surgery. The aim of this study was to determine whether morphine levels in the plasma would be enhanced by open laparotomy rather than by laparoscopic procedures. METHODS: We compared 19 patients who underwent laparoscopic cholecystectomy with five patients who underwent resection of the gallbladder by open laparotomy. Morphine levels in the plasma were measured by an electrochemical detection system. RESULTS: Postoperative endogenous morphine levels were higher with open laparotomy than with the laparoscopic technique (three h after surgery: open, 200 +/- 52.6 fmol/ml vs laparoscopy, 17.6 +/- 3.7, p < 0.01). This morphine elevation accounted for higher levels of cytokine, greater pain scores, and longer duration of fasting in open laparotomized patients than in laparoscopic cholecystectomy patients. Stress hormone levels in the plasma were also higher with open laparotomy than with laparoscopy. CONCLUSION: Morphine synthesis was enhanced by open laparotomy, resulting in greater biological response postoperatively than that seen with laparoscopic cholecystectomy.

Adrenocorticotropic Hormone↗
PubMed2000

The cytotoxic effects of bile acids in crude bile on human pancreatic cancer cell lines.

Pancreatic cancer frequently causes extrahepatic cholestasis. To identify the direct effects of bile acids in jaundiced serum on pancreatic cancer, the proliferation of PANC-1 and MIA PaCa-2 cells as well as the ultrastructural alteration of PANC-1 cells cultured in crude bile modified media were studied. The growth of these cells in the RPMI-1640 media with or without 1%, 2%, and 4% of the refined crude bile was assessed after 48 and 96 h of incubation. The ultrastructure of PANC-1 cells was investigated by scanning and transmission electron microscopy after 24 and 48 h of incubation. The proliferation of both cell lines in the bile-treated media was greatly inhibited. The inhibitory rates of bile on PANC-1 ranged from 24.1% +/- 3.3% to 66.9% +/- 6.6% (P < 0.01) and those on MIA PaCa-2 ranged from 16.7% +/- 3.8% to 50.7% +/- 5.5%. (P < 0.01). When the bile-added media were replaced, the cells were able to restore their proliferating ability. The PANC-1 cells incubated in the bile-supplied media indicated that the mirovilli, mitochondria, and other organelles had thus been injured. These results suggest that bile acids appear to inhibit the proliferation of PANC-1 and MIA PaCa-2 cells, and the probable inhibitory mechanism is mainly considered to be due to the cytotoxicity of such bile acids.

Bile Acids and Salts↗
PubMed2000

Reconstruction of the vena cava with the peritoneum.

BACKGROUND: Reconstruction of the vena cava with an autologous vein requires extra incisions. Prosthetic material is associated with an increased risk of infection. We therefore created an animal model of vena cava reconstruction using the peritoneum. METHODS: A 2.5 x 2.5 cm piece of peritoneum was resected from 7 pigs weighing 30 to 40 kg. An oval window (long axis: 1.5 cm) was made in the infrarenal vena cava. This was repaired with the peritoneal patch fixed in alcohol. RESULTS: In 2 animals sacrificed at 5 hours, there was no evidence of thrombosis, but there was fibrin clot on the patches. Two animals sacrificed on day 8 exhibited excellent patency of the vena cava. Complete endothelialization of the patch was noted at day 15. At 6 weeks, the vena cava was healed. No infections or other problems were noted. CONCLUSIONS: The peritoneum is an accessible and safe substitute for reconstruction of the vena cava.

Animals↗
PubMed2000

New target region of allelic loss in hepatocellular carcinomas within a 1-cM interval on chromosome 6q23.

BACKGROUND/AIMS: Frequent allelic losses on the long arm of chromosome 16 in several types of human cancers have suggested that 16q harbors one or more genes that are important for suppressing tumorigenesis in the tissues in question. METHODS: To identify the locations of putative tumor suppressor genes involved in hepatocellular carcinoma, we examined 96 primary hepatocellular carcinomas for their patterns of allelic loss at 18 microsatellite marker loci distributed along this chromosome arm. RESULTS: Allelic loss at one or more loci was observed in 48 (50%) of these tumors. The highest frequency of loss of heterozygosity (42%) was observed with marker D6S311 on chromosome 6q23. Through detailed deletion mapping of tumors having partial or interstitial deletions, we identified two commonly deleted regions at 6q23 and at 6q26-27. CONCLUSIONS: The common region at 6q23 lay within a 1-cM interval, flanked by D6S977 and D6S311. The previously documented deletion region that includes the M6P/IGF2R locus was confined to a 20-cM region at band 6q26-27 in our panel of tumors. The location we defined at 6q23 for a putative suppressor of hepatocellular carcinoma has not been reported before.

Adult↗
PubMed2000

Clinical implications of minimal disease in the bone marrow and peripheral blood in neuroblastoma.

PURPOSE: In patients with neuroblastoma (NB), minimal disease (MD) in bone marrow (BM) and peripheral blood (PB) is thought to play an important role in metastasis. The current study was designed to evaluate the clinical implications of the detection of MD in NB at the initial diagnosis. METHODS: Expression of the neuroendocrine protein gene product 9.5 (PGP9.5) and tyrosine hydroxylase (TH) mRNA in BM and PB obtained from 18 patients with NB was investigated by reverse transcriptase-polymerase chain reaction (RT-PCR). RESULTS: MD was detected in the BM obtained from 4 of 14 localized NB patients and also in the PB from 2. However, it was found also in both the BM and PB obtained from all 4 patients with metastatic NB. Two of the 4 MD-positive patients with localized NB had metastatic recurrence after a complete tumor excision. They also had unfavorable biological prognostic factors compared with the other 2 who did not have recurrent disease. CONCLUSION: MD detected by RT-PCR in the BM and the PB of patients with NB thus suggests a risk for metastatic disease, which in association with other unfavorable biological features may indicate a poor prognosis.

Adolescent↗
PubMed2000

Improved survival for patients with advanced neuroblastoma after high-dose combined chemotherapy based in part on N-myc amplification.

BACKGROUND/PURPOSE: In spite of many different kinds of chemotherapy for neuroblastoma, the prognosis for advanced neuroblastoma remains unsatisfactory. In particular, the outcome of advanced neuroblastoma with high copies of the N-myc gene tend to be poor. Therefore, the new high-dosage combined chemotherapy regimens for advanced neuroblastoma based in part on the N-myc amplification status has been utilized in the Kyushu area of Japan since 1991. This study aims to investigate whether these new regimens based in part on N-myc amplification have improved the survival rate of stage III and stage IV patients in comparison with the old regimens. METHODS: Between 1983 and 1995, 77 patients over 1 year of age and with stage III or IV neuroblastoma were registered in the Kyushu Area. Between 1983 and 1990, 49 patients received 1 of 2 combined chemotherapy regimens consisting of cyclophosphamide, cisplatin plus VM-26, and Adriamycin plus DTIC. Since 1991, two new regimens (New A1 and A3) have been administered based on the N-myc amplification status in a total of 28 patients. The New A1 regimen, which consists of cyclophosphamide, cisplatin, Adriamycin, and VP-16 has been administered in cases of less than 10 copies of N-myc, whereas the A3 regimen, consisting of a higher dose of cyclophosphamide, cisplatin, Adriamycin, and VP-16, has been administered in cases of more than 10 copies of N-myc. The survival rate was then compared between the old regimens and the new regimens. RESULTS: The 3-year survival rate (61.5%) for patients treated by the new regimens was significantly higher than that (32.7%) for patients treated by the old regimens (P <.01). Regarding the 24 cases of more than 10 copies of N-myc, the 3-year survival rate (35.9%) of the 13 patients treated by the A3 regimen was higher than that (0%) of the 11 patients treated by the old regimens (P <.05). However, in the 19 stage IV patients treated by the new regimens, the 3-year survival rate (11.1%) of the 9 cases of more than 10 copies was significantly lower than that (77.8%) of the 10 cases of less than 10 copies of N-myc (P <.01). CONCLUSIONS: These results suggest that high-dose combined chemotherapy based in part on the N-myc amplification status significantly improved the prognosis of patients with advanced neuroblastoma. However, stage IV patients with N-myc amplification still require a more effective treatment modality.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed2000

The characteristics of mediastinal neuroblastoma.

The prognosis of mediastinal neuroblastoma has been reported to be better than for other neuroblastomas. The reason for this is however not clear. Furthermore, a comparison between mediastinal neuroblastoma and the other neuroblastomas has been rarely reported so far. In this study, the characteristics of mediastinal neuroblastoma (84 cases) are investigated and compared with those of other neuroblastomas (440 cases). Regarding clinical factors, the age distribution and the rate of cases detected at mass screening were similar in both groups. According to Evan's staging system, the rates of early stage (I, II) were 62% in the mediastinal neuroblastoma and 38% in the other neuroblastomas (p<0.001). Regarding the biological prognostic factors, a favorable histology based on Shimada's classification was found in 100% (35/35) of the mediastinal neuroblastoma cases and in 85% (112/132) of the other neuroblastoma cases (p<0.05). With regard to N-myc amplification, all of the examined 42 cases in mediastinal neuroblastoma had a N-copy number of less than 10 copies, while 32 of the examined 263 cases (12%) in the other neuroblastomas had an amplification of N-myc of more than 10 copies (p<0.05). The 5-year survival rates were 78% in the mediastinal neuroblastoma and 59% in the other neuroblastomas, respectively. Of the cases who underwent an incomplete resection of primary tumors in localized neuroblastoma, the 5-year survival rate of the mediastinal neuroblastoma cases was significantly more favorable than that of the other neuroblastomas. The majority of mediastinal neuroblastoma cases showed an early stage and favorable prognostic factors. It is likely that the clinical and biological prognostic factors of the tumor are therefore more closely correlated with the outcome of mediastinal neuroblastoma rather than the degree of the surgical resection. Regarding the treatment for mediastinal neuroblastoma, it is most important to evaluate the biology of the tumor after surgical resection.

Child, Preschool↗
PubMed2000

Analysis of the prognostic factors relating to better clinical outcome in ganglioneuroblastoma.

PURPOSE: To elucidate the precise reason for the better prognosis in ganglioneuroblastoma (GNB) than in neuroblastoma (NB), the prognostic factors (age at diagnosis, stage at diagnosis, primary site, N-myc amplification, Shimada classification, and ploidy) were analyzed. METHODS: A retrospective analysis of the 57 neuroblastoma cases (20 GNB cases and 37 NB cases), that had not been detected by mass screening over the past 19 years at the authors' institute, was carried out. RESULTS: A Kaplan-Meier analysis of the 5-year survival rates were 67.2% and 35.1% in cases of GNB and NB, respectively, and these rates were significantly higher in GNB (logrank test; P = .04631). No significant differences were seen between GNB and NB regarding the rate in patients 1 year of age or older (95.0% v 78.4%; P = .1005), the rate of advanced cases (60.0% v 78.4%, P = .1406), the rate of an unfavorable histology (Shimada classification, 54.5% v 68.4%, P = .4473), or the diploid pattern rate (75.0% v 76.9%, P = .9200). However, N-myc amplification was found exclusively in NB (amplified cases per examined cases; 15/31), and all cases with N-myc amplification died. When the 5-year survival rate was evaluated in the patient without N-myc amplification between GNB and NB, no significant difference was observed (logrank test; P = .8568). CONCLUSION: The better prognosis in patients with GNB was thus thought to be exclusively related to an absence of N-myc amplification.

Ganglioneuroblastoma↗
PubMed2000

[Liver transplant aspiration cytology to monitor the intragraft events].

Liver transplant aspiration cytology(TAC) contributes significantly to the differential diagnosis of transplanted liver graft dysfunction, since each of the possible causes induces characteristic cytological findings in the graft and peripheral blood. That is, TAC can differentiate various inflammatory changes as indicating acute rejection, viral infection, or bacterial infection. The key is the intensity of activated lymphocytes in the graft and in blood. Remarkable lymphocytic activation only in the liver graft indicates acute rejection, meanwhile in a case of viral infection the activation can be seen both in liver graft and blood. The patterns and degree of liver cell injury and cholestasis can also identify the reason for liver impairment. Several cases of acute rejection, viral infection, and subclinical acute rejection diagnosed by TAC were recognized on TAC slide preparations. Subclinical rejection, which means acute rejection appreciated only cytologically or histologically, can be followed without treatment unless the patient demonstrates jaundice and liver enzymes over 100 units. In a case of chronic rejection, TAC is not an appropriate method of diagnosis, because there are few infiltrating cells in the portal triad, and subsequently, no visible activated lymphocytes on TAC slides. Although TAC is not well accepted, it is an informative means preliminary to core biopsy, and its use is expected to become wide-spread in the future because it is a safe procedure with minimal invasiveness to patients, and useful for differential diagnosis. The use of TAC will lessen the frequency of performing more invasive core biopsy.

Adolescent↗
PubMed1999

Effect of intracerebroventricular injection of tumor necrosis factor alpha on gut mucosal protein turnover in mice fed enterally.

OBJECTIVE: The objective of this study was to determine whether mucosal protein turnover is enhanced by intracerebroventricular (ICV) injection of tumor necrosis factor alpha (TNF-alpha) in mice fed enterally. METHODS: Male B6C3F1 mice (n = 37, 20.0-25.0 g) were catheterized in the ICV space using stereotaxic coordination, and subsequently a catheter was inserted into the stomach for enteral feeding on Day 0. The animals were fed a standard mouse diet and water ad libitum for 4 days. On Day 4, enteral feeding was begun with a standard liquid diet, and either artificial cerebrospinal fluid (control) or recombinant human (Rh) TNF-alpha (5 ng/h) was continuously given via the ICV catheter using an osmotic pump. On either Day 5 or 7, the mice were sacrificed 10 min after injection of [U-(14)C]phenylalanine (5 microCi/mouse, ip). Fractional synthetic rates (FSRs) of jejunal mucosa and muscle were measured by the pool flooding technique. Interleukin-6 (IL-6) levels in the plasma were measured by ELISA. RESULTS: Body weight was significantly reduced by ICV injection of TNF-alpha, because muscle FSR was decreased with TNF-alpha. There were no differences in IL-6 levels in the plasma between the two groups. The FSR of jejunal mucosa was elevated by infusion of TNF-alpha as compared with control mice on both Days 5 and 7 [Day 5: (control) 99.5 +/- 17. 6%/day vs (TNF) 150.5 +/- 20.5%/day, P < 0.05; Day 7: (control) 54.8 +/- 8.8%/day vs (TNF) 102.7 +/- 19.1%/day, P < 0.05). CONCLUSION: injection of TNF-alpha enhanced the mucosal protein synthesis rate without elevating IL-6 levels as compared with control mice, suggesting that the central nervous system links to the gut to regulate mucosal protein turnover through cytokine in the brain, but plasma IL-6 is not involved in this linkage.

Animals↗
PubMed1999

The usefulness of conducting investigations on intra-abdominal bacterial contamination in digestive tract operations.

A bacteriological study of 108 cases of gastrointestinal surgery was conducted by analyzing intra-abdominal bacterial contamination (IABC) and postoperative surgical site infections (SSI). We utilized an anaerobic porter to detect intra-abdominal bacterial infection and transport bacteria to the laboratory. The positive IABC rate was 42.9% for gastric cancer surgery, 22.6% for biliary tract surgery, and 85.7% for colorectal cancer surgery. Most cases of SSI were IABC-positive, and isolated bacterial species from the SSI were similar to those from the IABC. In colorectal cancer surgery, a preoperative chemical intestinal preparation and the prophylactic use of antibiotics had a major influence on the sensitivity of bacteria isolated from the SSI. These data suggest that prophylactic antibiotics should be chosen from among those to which bacteria from the IABC are highly sensitive, and that therapeutic antibiotics should be chosen from among those to which bacteria isolated from the SSI are highly sensitive. Finally, the exploration of IABC enables us to predict the incidence of SSI.

Adult↗
PubMed1999

Sclerotherapy plus ligation versus ligation for the treatment of esophageal varices: a prospective randomized study.

BACKGROUND: We devised a new combined method of endoscopic variceal ligation and injection sclerotherapy, namely, endoscopic scleroligation, for the treatment of esophageal varices. The aim of this prospective randomized trial was to compare endoscopic scleroligation with endoscopic variceal ligation alone with regard to efficacy, complications, variceal recurrence, and survival. METHODS: Fifty-one patients with cirrhosis and esophageal varices were randomly assigned to be treated by endoscopic scleroligation (n = 25) or endoscopic variceal ligation (n = 26). In the initial session in the endoscopic scleroligation group, endoscopic injection sclerotherapy was performed with injection of 5% ethanolamine oleate around the lower esophagus to obliterate the feeding veins. This was followed by endoscopic variceal ligation from the injection site to the most orad varix. In subsequent sessions, endoscopic injection sclerotherapy was performed with 1% polidocanol. In the endoscopic variceal ligation group, that procedure was performed in all treatment sessions. RESULTS: Both methods were equally effective in achieving complete eradication of esophageal varices. Among the cases in which complete eradication was achieved, the 1- and 3-year cumulative recurrence rates in the endoscopic scleroligation group (9.5%, 22.1%) were significantly lower than those in the endoscopic variceal ligation group (61.9%, 72.2%) (p < 0.01). The survival rates and incidences of treatment-related complications have been similar among patients treated by both methods. CONCLUSIONS: Endoscopic scleroligation is superior to endoscopic variceal ligation in preventing variceal recurrence.

Aged↗