PubMed Health⌕ Search

Biomedical subjects

H Tajiri

Publications and source records attributed to H Tajiri.

At least 37 records · Page 2Linked to original sources
PubMed2001

Spatial assessment by magnetic resonance cholangiopancreatography for preoperative imaging in partial pancreatic head resection.

BACKGROUND: Partial pancreatic head resection has been recommended for intraductal papillary mucinous tumor (IPMT). We report the usefulness of preoperative assessment by magnetic resonance cholangiopancreatography (MRCP) compared with endoscopic retrograde cholangiopancreatography (ERCP). METHODS: We studied 12 cases of surgically resected IPMT in the pancreatic head. The MRCP and ERCP images were interpreted, and we examined the detection rate of each imaging technique for the Wirsung duct, the Santorini duct, the entire cystic tumor, and the communication between the tumor and the ducts. RESULTS: In all cases MRCP correctly identified the entire cystic tumor, and the communication between the tumor and the pancreatic ducts was seen in 64% of cases. In contrast, the detection rate by ERCP of the entire cystic tumor and of the communication between the cystic tumor and the ducts was only 8% and 18%, respectively. CONCLUSION: MRCP clearly showed the relationship of the cystic tumor and the pancreatic ducts and was very useful for preoperative imaging for partial pancreatic head resection.

Aged↗
PubMed2001

Duodenal tuberculosis with a choledocho-duodenal fistula.

A 22-year-old man visited our hospital (National Cancer Center Hospital East) complaining of fatigue and anorexia. A laboratory investigation demonstrated a biochemical 'picture' of obstructive jaundice. An abdominal CT showed a low density mass in the retropancreatic area with multiple enlarged periportal lymph nodes. Upper gastrointestinal endoscopy revealed active ulceration on the dorsal wall of the descending part of the duodenum, and histopathology of the biopsy specimen revealed an ulcer with reactive inflammatory cell infiltration; no tumor cells were detected. The possibility of neoplasm had been ruled out by the use of CT and angiography. The jaundice recovered spontaneously and the abdominal mass gradually decreased in size. Endoscopic retrograde pancreatography showed no evidence of pancreatic disease; however, endoscopic retrograde cholangiography showed a choledocho-duodenal fistula. This patient showed hypersensitivity against the tuberculin skin test and Mycobacterium tuberculosis was successfully detected in gastric juice by using a polymerase chain reaction method and culture. Biopsy samples obtained from the duodenal ulcer at the second upper gastrointestinal endoscopy showed chronic inflammation with an epithelioid granuloma, suggesting tuberculosis. We thus diagnosed this case as a duodenal tuberculosis with a choledocho-duodenal fistula. To the best of our knowledge, there has been no report available of duodenal tuberculosis being the cause of a choledocho-duodenal fistula.

Adult↗
PubMed2001

New endoscopic treatment for intramucosal gastric tumors using an insulated-tip diathermic knife.

BACKGROUND AND STUDY AIMS: For one-piece resection the conventional technique of endoscopic mucosal resection (EMR) is limited to gastric mucosal tumors of 10 mm or less in size. In this retrospective study, we investigated the efficacy and complications associated with a new EMR method, using an insulated-tip diathermic knife (IT-EMR). PATIENTS AND METHODS: In a total of 41 patients gastric mucosal tumors were resected using IT-EMR. RESULTS: One-piece resection rates were 82% (14/17) for lesions of 10 mm or less, 75% (12/16) for those between 11 and 20 mm, and 14% (1/7) for those of over 20 mm. Complication rates for severe bleeding and perforation were 22% and 5%, respectively. With a median follow-up period of 32 months, no recurrence was observed after these procedures. CONCLUSIONS: Compared with conventional EMR, this new method may have significant benefits, particularly regarding one-piece resection of lesions between 11 and 20 mm in size, and may also have a lower recurrence rate.

Adenocarcinoma↗
PubMed2001

Assessment of colorectal lesions using magnifying colonoscopy and mucosal dye spraying: can significant lesions be distinguished?

BACKGROUND AND STUDY AIMS: Assessing the nature of lesions at the time of colonoscopy is important, and magnifying colonoscopy allows examination of mucosal crypt patterns. In this study, we assessed mucosal crypt patterns to see whether we could predict the histological findings. PATIENTS AND METHODS: This retrospective study of total colonoscopy using magnifying colonoscopy involved 4445 patients between December 1993 and July 1998 at the National Cancer Center Hospital East. The mucosal crypt patterns of 3438 lesions were observed under magnifying colonoscopy with 0.2% indigo carmine solution, and classified according to a modified Kudo classification (type I to V). After endoscopic or surgical resection (3291 cases and 147 cases, respectively), histopathological examination was performed. RESULTS: The diagnostic accuracy of magnifying endoscopy for non-neoplastic lesions was 75% (117/157), for adenomatous polyps it was 94% (3006/3186), and for invasive carcinomas it was 85 % (81/95). CONCLUSIONS: The combination of magnifying colonoscopy and dye spraying is helpful in determining the nature of colonic lesions as non-neoplastic, adenomas, or invasive carcinomas. Therefore it may be possible to determine, at the time of colonoscopy, which lesions require no treatment, which can be removed endoscopically, and which should be removed by surgery.

Adenocarcinoma↗
PubMed2001

Cytomegalovirus hepatitis confirmed by in situ hybridization in 3 immunocompetent infants.

We present 3 cases of immunocompetent infants with CMV infection who showed prolonged liver dysfunction. In all cases the CMV genome was detectable in hepatocytes using the in situ hybridization method. Combination therapy with ganciclovir (GCV) and hyperimmune gammaglobulin (HGG) was instituted in 2 cases and successfully suppressed the replication of CMV, with sustained improvement in liver function. In 1 of these cases, signals for CMV DNA were undetectable in the liver 12 months after termination of combination therapy. These results help to confirm the etiology of CMV for persistent hepatitis in immunocompetent infants using the in situ hybridization method and also show the efficacy of combination therapy with a virostatic agent, GCV, and an immune-modulating agent, HGG.

Antiviral Agents↗
PubMed2001

Prospective study of mother-to-infant transmission of hepatitis C virus.

BACKGROUND: Mother-to-infant transmission of hepatitis C virus (HCV) could become the main route of HCV infection in the future because there are no methods available to prevent vertical infection. The aim of this study was to determine the incidence of mother-to-infant transmission in infants born to mothers who tested positive for anti-HCV antibodies and to elucidate associated risk factors for transmission. METHODS: Screening was conducted for 16,800 pregnant women with an anti-HCV antibodies test, and 154 mothers were positive. From the positive group 141 mothers were enrolled in the study and their 147 infants were followed from birth for serum alanine aminotransferase activity, anti-HCV antibodies and HCV RNA. HIV infection was tested in 73 of 141 mothers, all of whom were negative. RESULTS: Thirty-three infants were dropped from the study because they were followed for <6 months or were not tested adequately. Of the 114 infants finally evaluated 9 (7.8%) had detectable HCV RNA. The transmission rate was not influenced by the mode of delivery [vaginal delivery, 8 of 90 vs. cesarean section, 1 of 24 (P = 0.396)] or by the type of feeding [9 of 98 for breast-fed infants vs. 0 of 16 for formula-fed infants (P = 0.243)]. All infected infants were born to mothers who had HCV viremia at the delivery (P = 0.040) and to those with a high viral load (P = 0.019). CONCLUSIONS: Our prospective study showed that the transmission rate of mother-to-infant HCV infection was 7.8% in anti-HCV antibody-positive mothers. Risk was related to the presence of maternal HCV viremia at delivery and a high viral load in the mothers.

Alanine Transaminase↗
PubMed2001

Serological Immunoglobulin G antibody titers to Helicobacter pylori in Japanese Brazilian and Non-Japanese Brazilian gastric cancer patients and controls in São Paulo.

Helicobacter pylori (H. pylori) infection is considered a cause of gastric cancer (GC), though evidence for this association is scarce in high-risk areas. Possible case control and/or ethnic differences were investigated as to the presence of H. pylori and its immunogloblin G antibody titer in the multi-ethnic city of São Paulo, where the incidence of GC is relatively high. We performed a cross-sectional comparison of antibody titers to H. pylori in Japanese Brazilian, and non-Japanese Brazilian GC patients and their controls. Japanese Brazilian patients were matched by age, sex and ethnicity with two controls, while non-Japanese Brazilian patients were matched as above with one control. Among Japanese Brazilians, 59 of 93 (63.4%) patients with GC and 127 of 186 (68.3%) controls were positive for H. pylori-specific antibody (odds ratio (OR) = 0.80, 95% confidence interval (CI) = 0.47 - 1.36), while among non-Japanese Brazilians, 171 of 228 patients with GC (75.7%) and 178 of 226 controls (78.8%) were positive (OR = 0.84, 95% CI = 0.54 - 1.30). The median serum antibody titer was lower in cases than in controls in both ethnic groups. A high titer (H. pylori titer > or = 50) was associated with less likelihood of GC for both ethnic groups (for Japanese Brazilians, OR = 0.39, 95% CI = 0.16 - 0.92; for non-Japanese Brazilians, OR = 0.56, 95% CI = 0.31 - 1.02). The high titer can be regarded as a sign of the necessity of eradication, and low titer is regarded as a sign of the necessity of close screening for GC in both ethnic groups, because extended atrophy may cause spontaneous disappearance of H. pylori from the stomach.

Adenocarcinoma↗
PubMed2001

Frequent detection of the human herpesvirus 6-specific genomes in the livers of children with various liver diseases.

This study was performed to investigate the frequency of human herpesvirus 6 (HHV-6) infection of the liver in children with a variety of liver diseases and to evaluate the role of HHV-6 infection in pediatric patients with prolonged non-B non-C hepatitis. Detection of the HHV-6 genomes in liver, in peripheral blood mononuclear cells (PBMC), and in plasma was performed by PCR or by in situ hybridization. Liver biopsy materials from 48 patients, in whom HHV-6 infection was serologically confirmed, were available for PCR analysis. Sequences of the HHV-6B genome were detectable in the livers of 36 of 48 patients (75%). The presence of the genome was not associated with serum transaminase activities. The genome was detectable in PBMC of 22 of 31 (71%) patients tested. In these 31 patients HHV-6 was detected in both the livers and PBMC of 20, was detected in PBMC but not in the livers of 2, was detected in the livers but not in PBMC of 3, and was detected in neither of samples of 6. In situ hybridization of the livers of six patients showed the presence of the HHV-6B genome in the nuclei of hepatocytes. The anti-HHV-6 immunoglobulin M antibody was detectable in 2 of 9 of the non-B non-C hepatitis patients, whereas none of the 22 patients with etiology-defined liver diseases tested positive. Cell-free viral DNA was not detectable in either group of patients. Our results showed that HHV-6B is frequently present in the livers of children with a variety of liver diseases but do not support the assumption that HHV-6B infection of the liver is associated with prolonged non-B non-C hepatitis.

Adolescent↗
PubMed2001

Three cases with TT virus infection and idiopathic neonatal hepatitis.

We present three cases of infants with idiopathic neonatal hepatitis showing diffuse intrahepatic fatty degeneration. Prolonged cholestasis has improved immediately upon intravenous administration of a high-dose gammaglobulin treatment in all three patients. The TT virus (TTV) genome was detectable in the serum of two patients, in the duodenal fluid of one and in the liver of all three. By analyzing sequence homology, we observed that the respective TTV isolated from serum, duodenal fluid and liver tissue were completely identical in cases 2 and 3. These findings suggest that TTV infection was one of the contributing factors for neonatal cholestasis in these patients. TTV was isolated from the serum of two out of the three mothers. The viruses were either completely or almost identical in sequence to those isolated from their respective infants, suggesting that they had been transmitted from mother to infant in these 2 cases. The patients presented here, whose livers were infected with the TTV and showed a favorable response to gammaglobulin therapy, may represent a subset of idiopathic neonatal hepatitis patients.

Cholestasis↗
PubMed2001

Urine-based enzyme-linked immunosorbent assay for the detection of Helicobacter pylori infection in children.

OBJECTIVE: Serology and (13)C-urea breath test have been widely used as noninvasive tests to detect Helicobacter pylori infection. However, easier collection of samples and lower costs are desirable for diagnosis of the individual patient or for use in epidemiologic studies. Our aim was to study the diagnostic accuracy of a recently developed urine-based enzyme-linked immunosorbent assay (ELISA) kit for the detection of H pylori-specific immunoglobulin G (IgG) antibodies in children. STUDY DESIGN: Specimens of serum and randomly voided urine were collected from 816 children (0-15 years old) and were analyzed using 2 serum-based ELISA kits and a urine-based ELISA kit, respectively. Based on results of serology, the sensitivity, specificity, and accuracy of the urine-based ELISA kit were evaluated. With regard to false-positive and false-negative results, urinary IgG concentrations and IgG/creatinine levels were studied. RESULTS: Both serum-based ELISAs were positive in 41 children and were negative in 666, who were enrolled in this study. The remaining 109 children were excluded because of disagreement between the results of the 2 serum-based ELISAs, including indeterminate values. Overall sensitivity, specificity, and accuracy of urine-based ELISA test compared with serology were 85.4%, 95.5%, and 94.9%, respectively. On positivity rates, the urine-based ELISA was closely coincident with the serum-based ELISA in each age group. There was no correlation between antibody levels detected by urine-based ELISA and each serum-based ELISA. Urinary IgG concentrations and IgG/creatinine levels were significantly higher in false-positives and were lower in false-negatives than in true-positives plus true-negatives for serology. Most of those with false-positive results had trace to moderate proteinuria. CONCLUSIONS: The urine-based ELISA is an alternative to serum-based ELISA for diagnosis of H pylori infection in children and should be suitable for large-scale epidemiologic studies concerning the organism. In children with proteinuria, results of the test should be interpreted with caution. It is possible that the urine-based ELISA method would be applicable to diagnosis of other infectious diseases.

Adolescent↗
PubMed2001

Routine endoscopy using electronic endoscopes for gastric cancer diagnosis: retrospective study of inconsistencies between endoscopic and biopsy diagnoses.

To clarify the actual conditions and problems encountered in the diagnosis of gastric cancer during routine endoscopic examinations using electronic endoscopes, a retrospective study of cases that had shown inconsistencies between the endoscopic and biopsy diagnoses was conducted. The subjects were 5,640 patients who had undergone gastric biopsies. They were selected from among 18,248 patients in whom upper gastrointestinal endoscopy had been performed between July 1992 and July 1997 at the National Cancer Center Hospital East. The study was conducted focusing on macroscopic type, size, location, and pathologic findings of the lesions. Cases showing inconsistencies between the endoscopic and biopsy diagnoses comprised 2.7% of all biopsy cases (150 of 5,640). Most of these inconsistently diagnosed lesions were less than 20 mm in diameter. The frequency of inaccurate diagnosis for depressed lesions in the areas of upper and middle thirds of the stomach from the lesser curvature to the posterior wall was significantly higher in the inconsistent group, compared with the accurate diagnoses from the control group. In diagnostic reviews of depressed lesions, 46.0% (46 of 100) were diagnosed accurately, but cases with fewer malignant indices were recognized. These results indicate that diagnostic accuracy must be enhanced through objective biopsy-implementation standards and the use of image processing in using diagnostic methods that employ electronic endoscopes.

Adenoma↗
PubMed2001

[Hepatitis virus C infection in children].

The prevalence of hepatitis C virus(HCV) infection has been becoming much lower in childhood. Blood transfusion was the principal transmission route of HCV in children. Since the year of 1989, screening of the blood products for HCV antibodies has markedly reduced transfusion-related HCV infection. Mother-to-infant transmission occurs in less than 10% of infants born to HCV-infected mothers. The maternal viral load is the most important factor determining the risk. The natural history and the outcome of HCV infection in childhood dependent on host and viral factors. The rate of progression to chronicity is 60% in post-transfusion infection and 80% in vertical infection. Experience of interferon therapy of chronic hepatitis C in children is limited, with about 50% having a sustained response to the therapy.

Child↗
PubMed2000

Interferon treatment on glomerulonephritis associated with hepatitis C virus.

We report on a 10-year-old girl with glomerulonephritis associated with hepatitis C virus infection, who was treated with interferon-alpha. On the first renal biopsy at 8 years of age, mild mesangial hypercellularity in a segmental to semiglobal pattern was present in all glomeruli. After 6 months interferon-alpha therapy, proteinuria diminished completely. However, mesangial proliferation was advanced on the second biopsy at 10 years of age. We concluded that the interferon-alpha was effective in the treatment of proteinuria despite the lack of pathological improvement.

Antiviral Agents↗
PubMed2000

A synthetic peptide of human apoprotein E with antibacterial activity.

In recent years, several endogenous mammalian antibacterial peptides have been described. An amphipathic cationicalpha-helix is a common feature in many cases; therefore, other peptides with this characteristic might also possess antibiotic activity. In fact, a 30-mer peptide of apoprotein E 133-162 (LRVRLASHLRKLRKRLLRDADDLQKRLAVY) was found to have antibiotic activity comparable to those of a classic antibiotic (Gentamicin) and a neutrophil-derived antibiotic peptide (CAP18). Calculation of cationicity, hydrophobicity, and hydrophobic moment and the helical wheel diagram of apoprotein E 133-162 revealed close similarities to CAP18.

Amino Acid Sequence↗
PubMed2000

A short peptide derived from the antisense homology box of Fas ligand induces apoptosis in anti-Fas antibody-insensitive human ovarian cancer cells.

We found that a short synthetic peptide corresponding to the "antisense homology box" of Fas ligand induced apoptotic cell death of Fas-expressing human ovarian cancer cell lines. The peptide was deduced from residues 256-265 of human Fas ligand, based on the hypothesis that it should contain a specific binding site to the corresponding Fas. Interestingly, the ovarian cancer cell line NOS4, which was sensitive to anti-Fas antibody induced apoptosis, was not affected by the peptide, whereas another cell line, SKOV-3, which was insensitive to anti-Fas antibody, was killed by the peptide. Thus, this short peptide was shown to have a unique activity to induce apoptosis in human ovarian cancer cells in a manner different from anti-Fas antibody.

Antibodies, Monoclonal↗
PubMed2000

Correlation of in vitro autofluorescence endoscopy images with histopathologic findings in stomach cancer.

BACKGROUND AND STUDY AIMS: There is increasing interest in the use of autofluorescence endoscopic imaging systems for the detection of malignancies in the gastrointestinal tract. The purpose of this study was to investigate the autofluorescent color of cancer lesions, and the detection rate of cancer areas using an autofluorescence endoscopic imaging system. Concurrent histopathologic examination was used for comparison. PATIENTS AND METHODS: This study involved a total of 50 stomach cancer patients (with a total of 61 lesions) undergoing surgery. Immediately after the resection, each lesion was observed using an autofluorescence endoscopic imaging system (LIFE-GI system, Light-Induced Fluorescence Endoscopy in the Gastrointestinal Tract). A total of 429 evaluation points in the specimens were selected according to tumor size. The images obtained in this way were assessed by comparison with histopathologic findings in terms of depth of invasion, thickness of the mucosa that had been invaded by cancer cells, and the histologic type of each cancer. RESULTS: Detection with the LIFE-GI system was possible in 58 of the 61 stomach cancer lesions (95.1%). When examined in detail with reference to sampling points, the detection rates of cancer areas according to depth of cancer cell invasion were 57.5 % for invasion to the mucosa, 74.3 % for invasion to the submucosa, and 88.1% for invasion to the muscularis propria or deeper. The detection rates increased as the depth of invasion increased, and they increased significantly as the mucosa invaded became thicker. Detection rates according to histologic type were 82% for differentiated cancer, and 61% for undifferentiated cancer. Most of the cancer areas appeared dark red. Light blue, brilliant red, and white areas were also observed. CONCLUSIONS: Mucosal thickening as a result of cancer cell invasion had a large impact on the detection rate of the LIFE-GI system. As a result, this method may not be useful for the detection of undifferentiated cancer, which may invade in a more dispersed manner, without altering the mucosal thickness.

Adult↗
PubMed2000

Recurrence after endoscopic mucosal resection for superficial esophageal cancer.

BACKGROUND AND STUDY AIMS: We present the results of endoscopic mucosal resection (EMR) for superficial esophageal cancer in patients treated at the National Cancer Center Hospital East since March 1993, and discuss the factors involved in local recurrence. PATIENTS AND METHODS: The study consisted of 51 patients with a total of 57 superficial esophageal cancers which were treated by EMR at the National Cancer Center Hospital East between March 1993 and March 1998. EMR was performed with a two-channel fiberscope or with the assistance of the endoscopic esophageal mucosal resection tube. Follow-up examinations by means of endoscopy with iodine staining and biopsy were repeated every 3-6 months. RESULTS: A total of 19 patients had double cancers; 12 had head and neck cancers (HNC), six had stomach cancers, and one had lung cancer. The patients with HNC tended to have multiple iodine-unstained areas, and multiple cancers in the esophagus. Local recurrence was detected in two out of five patients (40%) with multiple esophageal cancers, and in two out of 46 patients (4%) with solitary cancer (P=0.0433). There was no difference in the rate of local recurrence between patients with HNC and those without HNC. Three out of four patients with recurrent cancers were given additional treatment, EMR for two and radiotherapy alone for one; no further recurrence occurred except in the patient who underwent radiotherapy alone. CONCLUSIONS: Multiplicity of cancer is a risk factor for local recurrence. Appropriate additional treatment should be indicated for recurrent lesions.

Aged↗