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N Sato

Publications and source records attributed to N Sato.

At least 73 records · Page 4Linked to original sources
PubMed2003

The effects of frequency-encoding gradient upon detectability of the margins and height measurements of normal adult pituitary glands.

We investigated the effects of frequency-encoding gradient (FEG) upon detectability and height measurements of the normal adult pituitary gland. We obtained two sets of T1-weighted sagittal images of the pituitary gland from 70 adult subjects without known pituitary dysfunction using 1.5 tesla imagers; one with an inferior-superior FEG, and one with an anterior-posterior FEG. We classified the subjects into three types according to the distribution of fatty marrow in the clivus. Each set of images was assessed for pituitary height on midline sagittal images, and detectability of pituitary margins. Height measurements and detectability scores were evaluated for significant difference between the two FEGs. In subjects with fatty marrow in the clivus, there was significant difference between pituitary height measurements (P < 0.005) and pituitary margin detectability (P < 0.001). Care should be taken to image the pituitary gland using an anterior-posterior FEG.

Adult↗
PubMed2003

Gliomatosis cerebri evaluated by 18Falpha-methyl tyrosine positron-emission tomography.

Gliomatosis cerebri is a rare condition in which an infiltrative glial neoplasm spreads through the brain with preservation of the underlying structure. CT and MRI show diffuse abnormal density or signal, without mass effect, and because these findings are nonspecific, it is difficult to make a definitive diagnosis. Our purpose was to assess the usefulness of a new tumour-detecting amino acid tracer for positron-emission tomography (PET), L-[3-(18)F] alpha-methyl tyrosine (FMT), in patients with gliomatosis cerebri. We performed FMT PET, fluorodeoxyglucose FDG PET and MRI eight patients with gliomatosis cerebri and six with non-neoplastic disease, whose MRI also showed diffuse high signal on T2-weighted images. Standardised uptake (SUV) of FMT and FDG in the area of gliomatosis was obtained and the tumour-to-normal cortex (T/N) ratio of this was compared. The tumours were shown on FMT PET as areas of increased uptake, except in one patient with severe intracranial hypertension. There were significant differences between the SUV of FMT and the T/N ratio of FMT in patients and in controls (both P<0.01), and between the T/N ratio of FMT and FDG in patients ( P<0.01). Increased uptake of FMT PET strongly suggests neoplasia. FMT PET is valuable for differentiating gliomatosis cerebri from non-neoplastic diseases showing similar diffuse high signal on T2-weighted images and little contrast enhancement.

Adult↗
PubMed2003

Aberrant methylation of suppressor of cytokine signalling-1 (SOCS-1) gene in pancreatic ductal neoplasms.

The suppressor of cytokine signalling-1 (SOCS-1) gene is frequently silenced in human hepatocellular carcinoma by aberrant methylation. The aim of this study was to determine if SOCS-1 is inactivated in pancreatic ductal neoplasms, and to investigate if aberrant methylation of this gene affected the Janus kinase/signal transducers and activators of transcription (JAK/STAT) pathway. Aberrant methylation in the CpG island of the SOCS-1 gene was detected in six of 19 (31.6%) human pancreatic cancer cell lines using methylation-specific PCR, and was associated with a loss or reduction of gene expression in five of the six methylated cell lines. Thirteen of 60 pancreatic ductal adenocarcinomas (21.7%) and two of 34 intraductal papillary mucinous neoplasms (IPMNs) (5.9%) had methylated SOCS-1. In contrast, SOCS-1 methylation was not seen in pancreatic normal ductal epithelia (zero out of 15), in pancreatic intraepithelial neoplasia (PanINs) (zero out of 49) or in the IPMNs without infiltrating cancer (zero out of 20). 5-Aza-2'-deoxycytidine treatment of the SOCS-1-methylated pancreatic cancer cell lines led to restoration of SOCS-1 gene expression. Interleukin-6, which has been shown to act through the JAK/STAT pathway to increase cell growth, induced modest time and dose-dependent cell proliferation in a SOCS-1-methylated cell line (PL10, P=0.015) but not in two unmethylated cell lines. These results indicate that loss of SOCS-1 gene is associated with transcriptional silencing and may have growth-promoting effects, and that its methylation is a useful marker of pancreatic cancer.

Adult↗
PubMed2003

High incidence and spontaneous resolution of mastoid effusion after craniotomy on early postoperative magnetic resonance images.

Mastoid effusion is a poorly understood complication after craniotomy. The incidence and severity of postoperative mastoid effusion were retrospectively examined on postoperative magnetic resonance (MR) images to assess any association with craniotomy procedures, time course, and neuro-otological complications. We evaluated the early postoperative MR images (within 4 days of craniotomy) and medical records of 74 patients who underwent 77 operations for the treatment of various intracranial diseases from January 2000 to December 2001. Mastoid effusion was classified into four grades: none, partial, moderate, and severe diffuse effusion in the mastoid air cells. Thirty-three follow-up MR images from 26 patients were also reviewed. Postoperative mastoid effusion occurred ipsilateral to the craniotomy site in 62 cases and contralateral in 56 cases. Mastoid effusion was significantly more severe ipsilateral than contralateral to craniotomy with exposure of the mastoid air cells ( P<0.0001). There was no significant difference in severity between the contralateral and ipsilateral sides after craniotomy without mastoid air cell opening ( P=0.437). Mastoid effusion following craniotomy without exposure of mastoid air cells resolved within 3 months. However, otitis media with effusion developed in six patients with severe mastoid effusion ipsilateral to craniotomy with exposure of the mastoid air cells. Mastoid effusion frequently developed on both sides. Any grade of mastoid effusion on the ipsilateral side to craniotomy without exposure of mastoid air cells, or on the contralateral side, was asymptomatic or had a benign course, and disappeared within 3 months.

Brain Neoplasms↗
PubMed2003

Is antimicrobial susceptibility testing necessary before second-line treatment for Helicobacter pylori infection?

BACKGROUND: An antimicrobial susceptibility test for Helicobacter pylori before second-line treatment is often performed, although whether the test is truly necessary remains unknown. PATIENTS AND METHODS: Eighty-two patients with H. pylori infection for whom first-line treatment with a 1-week proton pump inhibitor/amoxicillin-clarithromycin (AC) regimen had failed were randomly assigned to two groups: those having or not having the susceptibility test before re-treatment. The cure rates for these two groups were compared. RESULTS: Five of the 82 patients were excluded from the analysis. For 38 patients in the susceptibility-test group, we used what we considered the best regimen based on susceptibility testing: 10 patients [no resistance to clarithromycin (CAM)] received the lansoprazole-amoxicillin-clarithromycin regimen, 22 patients [19 CAM resistant, metronidazole (MNZ) susceptible; three failure of culture] were given the lansoprazole-amoxicillin-metronidazole (LAM) regimen, and six patients (both MNZ and CAM resistant) received dual therapy with omeprazole (OPZ) and amoxicillin (AMOX) in which the OPZ dose was determined by the CYP2C19 gene polymorphism. For 39 patients in the group with no susceptibility testing, LAM regimens were prescribed. The intention-to-treat (ITT)-based cure rates in the groups with and without susceptibility testing were 81.6% (95% confidence interval; 66-92%) and 92.4% (79-98%), respectively, and there was no significant difference between these two groups. CONCLUSION: Susceptibility testing is not necessarily required before second-line therapy if the first-line treatment has been performed using proton pump inhibitor/AC regimens.

Adult↗
PubMed2003

The role of leptin during the development of mouse preimplantation embryos.

Leptin is known to regulate diverse reproductive functions, and recent studies have implicated involvement of leptin in the early mouse embryo development. The aim of the present study was to investigate the expression of leptin and its functional receptor (OB-Rb) in mouse oocyte and preimplantation embryo, and to examine whether leptin influenced the early embryo development. Leptin mRNA was detected in blastocyst and hatched blastocyst, and OB-Rb mRNA was detected in oocytes, 1-cell, 2-cell, morula, blastocyst and hatched blastocyst. As for the origin of leptin, leptin mRNA was identified in both the oviduct and uterus of the pregnant mouse. Furthermore, in the pregnant mouse, the levels of leptin in uterine fluid were higher than those in the non-pregnant mouse. Supplementation of culture medium with leptin promotes the development of preimplantation embryos from 2-cell stage to the blastocysts, fully expanded blastocysts and hatched blastocysts. Leptin significantly increased the total cell number of blastocysts, and the effect was preferentially observed in the trophectoderm. These findings raise the possibility that leptin regulates the development of mouse preimplantation embryo through a paracrine pathway.

Animals↗
PubMed2003

Expression of LDL receptor and uptake of LDL in mouse preimplantation embryos.

OBJECTIVES: The aim of this study is to address the role of low-density lipoprotein (LDL) on mouse preimplantation embryos. METHODS: The temporal expression of low-density lipoprotein receptor (LDLR) and side-chain cleavage cytochrome P450 (P450scc) mRNAs in mouse oocytes and preimplantation embryos up to the hatched blastocyst stage were analyzed by RT-PCR and nested PCR techniques. Simultaneously, the expression of LDLR in the protein level was analyzed by fluorescent immunohistochemistory at oocyte, 4-cell embryo and blastocyst. Uptake of LDL was analyzed using the LDL labeled with the fluorescent probe DiO. RESULTS: LDLR mRNA was detected at oocyte, 8-cell, morula, blastocyst and hatched blastocyst stages. P450scc mRNA was detected at oocyte, 1-cell, 2-cell, 4-cell, blastocyst and hatched blastocyst stages. LDLR protein was detected in blastocyst. P450scc protein was detected in oocyte, 4-cell, and blastocyst. LDL-DiO was taken into embryo at blastocyst stage and this uptake was competitively suppressed by excess unlabeled LDL. CONCLUSIONS: It is suggested from the present study that LDLR may play an essential role in uptake of exogenous LDL into blastocyst stage and cholesterol derived from LDL may be the source of steroid hormone synthesis.

Animals↗
PubMed2003

FDG-PET for preoperative differential diagnosis between benign and malignant soft tissue masses.

OBJECTIVE: To evaluate the standardized uptake value (SUV) of [(18)F]2-deoxy-2-fluoro- d-glucose at positron emission tomography (FDG-PET) for preoperative differential diagnosis between benign and malignant soft tissue masses. DESIGN: One hundred and fourteen soft tissue masses (80 benign, 34 malignant) were examined by FDG-PET prior to tissue diagnosis. The SUVs were calculated and compared between benign and malignant lesions and among different histologic subgroups which included three or more cases. RESULTS: There was a statistically significant difference in SUV between benign (1.80+/-1.42 [SD]) and malignant (4.20+/-3.16) soft tissue masses in total (P<0.0001). However, a considerable overlap in SUV was observed between many benign and malignant lesions. Liposarcomas (2.16+/-1.72) and synovial sarcomas (1.60+/-0.43) did not show significantly higher SUV than any benign lesions. Metastases (4.23+/-2.35) showed no statistically significant difference in SUV as compared with schwannomas (1.75+/-0.84), desmoids (2.77+/-1.32), sarcoidosis (3.62+/-1.53), or giant cell tumors of tendon sheath (GCT of TS; 5.06+/-1.63). Even malignant fibrous histiocytomas (5.37+/-1.40) could not be differentiated from sarcoidosis or GCT of TS, based on the SUV. CONCLUSIONS: A large accumulation of FDG can be observed in both benign and malignant histiocytic, fibroblastic, or neurogenic lesions. SUV at conventional FDG-PET is limited to differentiating benign from malignant soft tissue masses, when all kinds of histologic subtypes are included.

Diagnosis, Differential↗
PubMed2003

Degradation of arginine and other amino acids by butyrate-producing asaccharolytic anaerobic Gram-positive rods in periodontal pockets.

The use of 20 amino acids by butyrate-producing asaccharolytic anaerobic Gram-positive rods (AAGPRs) in periodontal pockets, i.e. Eubacterium minutum, Filifactor alocis, E. infirmum, E. sulci and E. saphenum, was studied. E. minutum used only arginine and lysine, and produced substantial amounts of butyrate and ammonia as the main metabolic products from arginine, and acetate, butyrate and ammonia from lysine. Fi. alocis used arginine alone and produced butyrate and ammonia. E. infirmum, E. sulci and E. saphenum used lysine alone and produced acetate, butyrate and ammonia. The growth of these bacterial species was supported and enhanced by arginine and/or lysine enriched to culture media, but not by the other amino acids. Arginine deiminase, ornithine carbamoyltransferase and carbamate kinase activity were detected in the cell-free extract of E. minutum, suggesting that arginine was metabolised to citrulline initially, and subsequently to ornithine and carbamoyl phosphate. Ornithine and carbamoyl phosphate were further converted to butyrate, and carbon dioxide and ammonia, respectively. Enzymatic activity of arginine deiminase and ornithine carbamoyltransferase was not detected in Fi. alocis, indicating that Fi. alocis converted arginine to ornithine directly, not via citrulline, and further to butyrate.

Ammonia↗
PubMed2003

Milrinone improves lung compliance in patients receiving mechanical ventilation for cardiogenic pulmonary edema.

BACKGROUND: Cardiogenic pulmonary edema is a frequent cause of respiratory failure. We investigated whether milrinone improved lung compliance. METHODS: We selected 10 patients with respiratory failure due to severe cardiogenic pulmonary edema to receive mechanical ventilation. Patients were administered a bolus injection of milrinone (50 microg kg-1) over 10 min, followed by continuous intravenous infusion (0.5 microg kg-1 min-1). Lung compliance, blood gas values, hemodynamic parameters, and sample plasma milrinone levels were assessed over 120 min after the onset of the continuous infusion of milrinone. RESULTS: Ten min following milrinone infusion, dynamic compliance (Cdyn) and static compliance (Cst) increased from 37 +/- 12 to 42 +/- 12 ml cmH2O-1 and from 40 +/- 13 to 45 +/- 12 ml cmH2O-1, respectively (P < 0.01). Plasma milrinone levels reached a therapeutic level for vasodilator and positive inotropic effect at 10 min after milrinone infusion. A significant decrease in mean pulmonary artery pressure and pulmonary artery wedge pressure occurred simultaneously with an increase in respiratory system compliance. However, an increase in cardiac index was observed later than these changes. There were significant correlations between the mean pulmonary artery pressure and Cdyn (r = -0.39, P < 0.01) and Cst (r = -0.38, P < 0.01). CONCLUSIONS: Milrinone-induced improvement in lung compliance along with an improvement of hemodynamics was found together with an inverse relationship between compliance and mean pulmonary artery pressure.

Aged↗
PubMed2003

Granulocyte transfusion as a treatment for enterococcal meningoencephalitis after allogeneic bone marrow transplantation from an unrelated donor.

Bacterial meningoencephalitis occurring in the pre-engraftment period after bone marrow transplantation (BMT) is a rare complication, and the feasibility of granulocyte transfusion (GTX) in such cases remains to be elucidated. A 37-year-old man developed enterococcal meningoencephalitis during a severely granulocytopenic pre-engraftment period after BMT. Despite therapy with appropriate antibiotics, cultures of blood and cerebro-spinal fluid (CSF) continued to grow Enterococcus faecalis, and he developed rapid mental deterioration and seizure. Granulocytes were collected from his HLA-mismatched, ABO-matched sibling with subcutaneous injection of granulocyte colony-stimulating factor (G-CSF) and oral dexamethazone. Transfusion of 4.4 x 10(10) granulocytes resulted in a 12-h post-transfusion granulocyte increment of 2.0 x 10(9)/l, and maintained peripheral blood granulocyte counts above 0.5 x 10(9)/l for 3 days. A rapid increase of granulocytes in CSF was also observed, and cultures of blood and CSF became negative after GTX. A transient worsening of seizure was observed as a potential side effect of GTX. The patient subsequently developed septic shock because of Pseudomonas aeruginosa and died. Further studies are warranted to evaluate the clinical efficacy of GTX for the treatment of uncontrolled infections in granulocytopenic stem cell transplant recipients.

Adult↗
PubMed2003

Induced HMGA1a expression causes aberrant splicing of Presenilin-2 pre-mRNA in sporadic Alzheimer's disease.

The aberrant splicing isoform (PS2V), generated by exon 5 skipping of the Presenilin-2 (PS2) gene transcript, is a diagnostic feature of sporadic Alzheimer's disease (AD). We found PS2V is hypoxia-inducible in human neuroblastoma SK-N-SH cells. We purified a responsible trans-acting factor based on its binding to an exon 5 fragment. The factor was identified as the high mobility group A1a protein (HMGA1a; formerly HMG-I). HMGA1a bound to a specific sequence on exon 5, located upstream of the 5' splice site. HMGA1a expression was induced by hypoxia and the protein was accumulated in the nuclear speckles with the endogenous splicing factor SC35. Overexpression of HMGA1a generated PS2V, but PS2V was repressed by cotransfection with the U1 snRNP 70K protein that has a strong affinity to HMGA1a. HMGA1a could interfere with U1 snRNP binding to the 5' splice site and caused exon 5 skipping. HMGA1a levels were significantly increased in the brain tissue from sporadic AD patients. We propose a novel mechanism of sporadic AD that involves HMGA1a-induced aberrant splicing of PS2 pre-mRNA in the absence of any mutations.

Alternative Splicing↗
PubMed2003

Increased circulating interleukin-12 (IL-12) p40 in pulmonary sarcoidosis.

In sarcoidosis, a T helper 1 (Th1) response is an essential event and the up-regulation of interleukin-12 (IL-12) has been detected in affected disease sites. In order to investigate the clinical usefulness of circulating IL-12, we measured the serum concentrations of IL-12 by ELISA and performed immunohistochemistry using specific MoAbs for IL-12 in the lungs and scalene lymph nodes of patients with sarcoidosis. The serum concentration of IL-12 p40 was detectable in all 45 patients with pulmonary sarcoidosis and 18 normal controls, whereas that of IL-12 p70 was undetectable. The serum concentrations of IL-12 p40 in pulmonary sarcoidosis were significantly higher than those of the normal controls, especially in cases with abnormal intrathoracic findings detected by chest roentogenogram. The serum concentrations of interferon-gamma (IFN-gamma) also increased compared with those of normal controls and there was a significant positive correlation between the serum concentrations of IL-12 p40 and IFN-gamma. Furthermore, serum angiotensin-converting enzyme (ACE) and lysozyme, which are known to be useful markers for disease activity in sarcoidosis, correlated well with the serum concentrations of IL-12 p40. The positive 67Ga scan group (for lung field) had significantly elevated serum IL-12 p40 levels compared with those of the negative group. No bioactivity of IL-12 p70 was detected in three sarcoid cases sera by using the IL-12 responsive cell line. Finally, the immunohistochemical approach revealed that IL-12 p40 was expressed in the epithelioid cells and macrophages of sarcoid lungs and lymph nodes. We concluded that the production of IL-12 p40 was far greater in the sera and we have demonstrated this to be a useful clinical marker for disease activity and the Th1 response in pulmonary sarcoidosis.

Analysis of Variance↗
PubMed2003

Expression of cAMP response element binding protein (CREB)-binding protein (CBP) and the implication in retinoic acid-inducible transcription activation in human salivary gland adenocarcinoma cell line HSG.

In the process of retinoic acid (RA) signaling, retinoic acid receptor interacts with a coactivator complex composed of various transcription cofactors such as CREB-binding protein (CBP)/p300 and p160 family member proteins represented by steroid receptor coactivator-1 (SRC-1)/NCoA1 and p300/CBP cointegrator protein (p/CIP)/ACTR. In order to investigate the relationship of CBP to the RA signaling in a human salivary gland (HSG) adenocarcinoma cell line, we examined the expression of CBP in the cells. Immunoprecipitation and immunoblotting of the nuclear extract of HSG cells with anti-human CBP antibody showed a specific 270-kDa band, indicating the expression of CBP in HSG cells. The immunocytochemical analysis confirmed the nuclear localization of CBP. The transfection of HSG cells with a luciferase reporter plasmid harboring an RA-response element at the 5'-upstream region of the reporter gene increased RA-dependent luciferase activity approximately 3-fold. Co-transfection with a CBP-expression plasmid and the luciferase reporter gene enhanced the RA-dependent transcription activation approximately 10-fold. The immunoprecipitates obtained with anti-CBP antibody exhibited a histone acetyl-transferase (HAT) activity 2-fold higher than that obtained with the control antibody, whereas the HAT activity of the immunoprecipitates with anti-SRC-1 and anti-p/CIP, which were used as comparisons, were only a little increased. The RA treatment had no effect on the level of HAT activity except in the case of using the immunoprecipitate obtained with anti-RARalpha, in which case it increased the activity. These findings indicate that CBP expressed in HSG cells mediates the RA-inducible growth and differentiation-regulating transcription activation in concert with the retinoic acid receptors.

Acetyltransferases↗
PubMed2003

A comparative study of 11C-choline PET and [18F]fluorodeoxyglucose PET in the evaluation of lung cancer.

The purpose of this study was to compare the diagnostic value of 11C-choline positron emission tomography (PET) and [18F]fluorodeoxyglucose (FDG) PET imaging in the detection of primary lung cancer and mediastinal lymph node metastases. Seventeen patients with histologically proven primary lung cancer were examined with both 11C-choline and FDG PET within a week of each study. Lung cancers were analysed visually and semiquantitatively using the ratio of tumour-to-normal radioactivity (T/N ratio) and standardized uptake value (SUV). Mediastinal lymph node metastases were analysed visually. Although both techniques delineated focal lesions with an increase in tracer accumulation in 13 patients, FDG PET identified three additional patients in whom 11C-choline PET did not visualize any lesion. In the detection of lung cancer <2 cm in size, FDG PET provided higher sensitivity (six of seven, 85.7%) than 11C-choline PET (four of seven, 57.1%). The T/N ratio and SUV were significantly higher with FDG PET (T/N ratio, 7.43+/-6.22; SUV, 4.05+/-3.05) than these were with 11C-choline PET (T/N ratio, 2.93+/-1.19; SUV, 2.93+/-0.79) (P<0.001). There was a significant positive correlation between the T/N ratios and SUVs of FDG and 11C-choline. In the assessment of mediastinal lymph node involvement, FDG PET detected lymph node metastases in two patients who were negative on 11C-choline PET, whereas both techniques could not detect tumour involvement in one patient. Both techniques have clinical value for the non-invasive detection of primary lung cancer that is 2 cm or greater in size. However, FDG PET is superior to 11C-choline PET in the detection of lung cancer that is less than 2 cm in diameter and in mediastinal lymph node metastases.

Adenocarcinoma↗
PubMed2003

Induction of experimental ulcerative colitis by Fusobacterium varium isolated from colonic mucosa of patients with ulcerative colitis.

BACKGROUND: Bacteria are implicated in certain forms of model chronic colitis but the identity and role of bacteria in human ulcerative colitis (UC) are uncertain. AIMS: To isolate pathogenic bacteria from inflamed mucosa of patients with UC, to examine whether the bacteria have a toxin to Vero cells, and to determine whether the toxin induces UC-like lesions in animals. METHODS: Bacteria were isolated from UC patients and supernatants from cultures were filtered and tested for cytotoxicity to Vero cells. Bacterial cells producing the cytotoxic supernatants were examined by polymerase chain reaction for verotoxin genes. Culture supernatants of cytotoxic strains were examined by high performance liquid chromatography for organic acid concentrations. Mice were given enemas containing organic acid at the mean concentration in the supernatants of cytotoxic strains to ascertain whether colonic lesions appear in UC. RESULTS: Only supernatants from cultures of Fusobacterium varium killed Vero cells. Bacterial cells lacked verotoxin genes. Bacterial culture supernatants contained high concentrations of n-butyric acid and the mean concentration (32 mmol/l) was cytotoxic to Vero cells. Twenty four hours after mice were given enemas containing either butyric acid or F varium culture supernatants, colonic ulcers with crypt abscesses, inflammatory cell infiltration, and apoptotic changes were observed. CONCLUSIONS: Butyric acid in culture supernatants from cultures of F varium caused UC-like lesions in mice. This study indicates that F varium may be one of the elusive pathogenic factors in UC.

Adult↗
PubMed2003

Helicobacter pylori infection induces duodenitis and superficial duodenal ulcer in Mongolian gerbils.

BACKGROUND: There is no direct evidence for an animal model of Helicobacter pylori induced duodenal ulcer. AIM: In this study we evaluated the roles of bacterial strain and age of experimental animals in induction of duodenitis and duodenal ulcer in Mongolian gerbils after H pylori infection. METHODS: Specific pathogen free Mongolian gerbils were inoculated orally with three bacterial strains (H pylori ATCC 43504, TN2GF4, and K-6, a clinical isolate from a patient with gastric cancer in our clinic). These strains have both the cagA gene and VacA. Five week old gerbils were used to emulate prematurity infection and 14 week old animals were used as mature test subjects. Animals were observed for 12 weeks after inoculation. Interleukin 8 (IL-8) production in gastric epithelial cells (MKN74) after coculture with the H pylori strains was measured by ELISA. RESULTS: Gastritis and gastric ulcers were found in all gerbils infected with the three strains. However, duodenitis and gastric metaplasia were seen more frequently in gerbils infected with TN2GF4 and K-6 strains than in the ATCC 43504 infected or control groups (p<0.05). Superficial duodenal ulcers with severe duodenitis and gastric metaplasia were found in two gerbils inoculated at 14 weeks with the TN2GF4 strain but none at five weeks. The TN2GF4 strain stimulated significantly higher levels of IL-8 than ATCC 43504 and K6 strains (p=0.0039). CONCLUSIONS: When injected into adult Mongolian gerbils, a specific strain (TN2GF4) of H pylori can induce duodenitis with gastric metaplasia and superficial duodenal ulcers. Induction of duodenal ulcer in an animal model fulfills the requirements of Koch's postulates for establishing a role for H pylori as a causative agent.

Age Factors↗