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Biomedical subjects

X Z Lin

Publications and source records attributed to X Z Lin.

At least 19 recordsLinked to original sources
PubMed2001

Easier hepatic resections with a straight needle.

BACKGROUND: A stainless-sheathed, straight needle with a hook near the top of the inner needle was designed to facilitate hepatic resections. METHODS: First, using this needle, two rows of interlocking mattress sutures were made along the division line; then, hepatic transection was performed between these rows by electrocautery or forceps. RESULTS: Since 1997, we have performed this kind of hepatic resections in 43 cases, including 9 right lobectomies, 5 bisegmentectomies, 7 segmentectomies, 4 subsegmentectomies, 2 partial hepatectomies, 15 left lateral segmentectomies, and 1 hepatorrhaphy. In most cases, intraoperative hemorrhage was minimal. Neither specified inflow nor backflow control procedures were needed. CONCLUSION: Use of this needle may reduce the difficulty of the technique and blood loss for right hepatic lobectomy, left lateral segmentectomy, and some segmental or partial hepatectomy procedures.

Blood Loss, Surgical↗
PubMed2001

Ranitidine bismuth citrate or omeprazole-based triple therapy for Helicobacter pylori eradication in Helicobacter pylori-infected non-ulcer dyspepsia.

AIM: To test the eradication rate of Helicobacter pylori by ranitidine bismuth citrate-based triple therapy, and evaluate the symptomatic response of Helicobacter pylori eradication therapy for non-ulcer dyspepsia. METHODS: A total of 59 consecutive Helicobacter pylori infected non-ulcer dyspepsia patients were randomly selected to receive either one of two triple therapy regimens, including metronidazole, amoxycillin plus ranitidine bismuth citrate (RAM group) or omeprazole (OAM group). To determine the success of eradication, patients underwent the 13C-urea breath test, 6 weeks and one year after treatment. The dyspeptic symptom scores were also assessed at the time of enrolment, 6 weeks and one year after treatment. RESULTS: Per-protocol and intention-to-treat eradication rates were 77.7% and 70% in RAM group and 83.8% and 68.9% in OAM group (p = non significant). At both the 6th week and at the first year after treatment, the mean symptom scores were lower than pre-treatment scores in the study population, regardless of whether treatment was successful or not. However, patients, whether eradicated successfully or not-eradicated, presented similar 6-week and 1-year scores. CONCLUSIONS: One-week RAM triple therapy, which is cheaper than the OAM regimen, is a relatively effective alternative regimen for Helicobacter pylori eradication in Taiwanese. Triple therapy for Helicobacter pylori eradication was not the whole management for the relief of dyspeptic symptoms of non-ulcer dyspepsia patients.

Adult↗
PubMed2001

Expression of oncogene products HER2/Neu and Ras and fibrosis-related growth factors bFGF, TGF-beta, and PDGF in bile from biliary malignancies and inflammatory disorders.

The expression of several growth factors and K-ras gene mutation in bile were studied to better understand the pathogenesis and improve early diagnosis of bile duct cancers. Bile samples were collected from 12 cholangiocarcinomas (CLC), 10 ampullary cancers (APC), 3 gallbladder cancers (GBC), 7 pancreatic cancers (PNC), 9 biliary tract infection (BTI), 8 biliary stone disease (ST), and 5 normal controls (NC). The highest mean value of TGF-beta in bile was in patients with BTI; the mean levels of bFGF and PDGF were highest in CLC, and patients with APC and CLC had higher expression of HER2/Neu than other groups. In bile, a K-ras gene codon 12 mutation was found in 5 of 6 (83%) cases of CLC by the PCR-RFLP method. The results suggest overexpression of bFGF, PDGF, and HER2/Neu and the presence of K-ras mutation are important for carcinogenesis of bile duct cancers, and detection of the above abnormalities in bile is helpful for early diagnosis.

Ampulla of Vater↗
PubMed2001

Protective effect of melatonin on renal injury of rats induced by bile duct ligation.

Oxygen radicals have been implicated in the pathogenesis of renal injury induced by extrahepatic cholestasis. We conduct this study to investigate whether melatonin can have a protective effect against such injury. Either normal saline or gentamicin with or without melatonin was injected into rats that received either a bile duct ligation or a sham operation. The serum levels of malondialdehyde and total antioxidative activity were measured. The kidney was fixed for histologic scoring of renal injury. The serum malondialdehyde level was highest in the rats that received both bile duct ligation and gentamicin injection. Treatment with melatonin significantly increased the serum total antioxidative activity and reduced the serum malondialdehyde concentration. The mean score of renal injury, highest in the rats receiving bile duct ligation and gentamicin injection, was significantly reduced with melatonin treatment. By reducing the systemic oxygen radicals, supplementation with antioxidants exerts a protective effect on the renal injury induced by extrahepatic cholestasis.

Animals↗
PubMed2001

Characterization of a proximal element in the rat preadipocyte factor-1 (Pref-1) gene promoter.

Preadipocyte factor-1 (Pref-1) was shown to negatively regulate adipocyte differentiation. We recently reported that ZOG, a rat homolog of Pref-1, was specifically expressed in the adrenal zona glomerulosa. Results of the investigation of Pref-1 expression in preadipocyte and in undifferentiated adrenal cortex suggested that down-regulation of Pref-1 gene was closely correlated with the differentiation process. In this study we demonstrate that an upstream region (from -76 to -47) of the rat Pref-1 gene was essential for its expression in adrenocortical carcinoma-derived H295R cells. A nucleotide sequence found in this region, GCGTGGGCGTGGGCGGGGG (Egr/GC-box), seemed to contain three elements, two early growth response (Egr) elements and one GC-box, overlapping each other. Mutations of four or five nucleotides in a 7-nucleotides-stretch in the midst of the Egr/GC-box eliminated the binding of Sp1/3, abolished the activation by Egr-factor(s) and diminished the Pref-1 promoter activity. When mutations were introduced into the outside of the middle portion, the binding of Sp1/3 to the Egr/GC-box was abolished similarly. However, the decrease in the promoter activity was less than that found with the construct mutated at the middle. These results indicated that an element present at the 7-nucleotides-stretch in the midst of the Egr/GC-box might be important for the Pref-1 promoter activity, and this proximal element was possibly activated by a still-unidentified nuclear factor(s). This element would function as the promoter of the Pref-1 gene in H295R cells, but not in HeLa cells.

Adipocytes↗
PubMed2001

Erythrocyte Lewis antigen phenotypes of dyspeptic patients in Taiwan--correlattion of host factor with Helicobacter pylori infection.

BACKGROUND AND AIMS: Because of the molecular mimicry between Helicobacter pylori lipopolysaccharide and host Lewis blood-group antigens, Lewis antigen may mediate specific H. pylori binding to surface epithelial cells in gastric mucosa. We, therefore, tested whether different Lewis antigen phenotypes have different prevalence rates of H. pylori infection, and determined the specific H. pylori-related disease entities or histologic features. METHOD: A total of 342 dyspeptic patients without previous anti-H. pylori therapy were enrolled after endoscopy. The Lewis phenotypes, defined as Le(a-b-), Le(a-b+), Le(a+b-), and Le(a+b+) subtypes, were determined from the expression or absence of Lewis antigens (Le(a) and Le(b)) on erythrocytes in each patient using monoclonal antibodies. The H. pylori-specific gastric histology was evaluated using the updated Sydney's system. RESULTS: Of 342 patients, 233 (68.1%) had H. pylori infection. The H. pylori infection rates were significantly higher in patients with Lewis phenotypes Le(a+b-) and Le(a+b+) (p < 0.05). Patients expressing the Le(a) antigen had a higher H. pylori infection rate than those without the Le(a) antigen (80.8 vs 64%, p < 0.005). In H. pylori-infected patients, patients expressing Le(b) antigen had a lower rate of gastroduodenal ulcers than those without Le(b) antigen (46.9 vs 61.4%, p < 0.05). H. pylori-positive patients who expressed the Le(b) antigen had higher bacterial density and inflammation severity in the gastric cardia than those who did not. Patients who expressed the Le(a) antigen had lower bacterial density, less chronic inflammation severity, and lower frequency of lymphoid follicles in the gastric cardia than those who did not (p < 0.05). CONCLUSION: The erythrocyte Lewis phenotype can be a significant host factor related to susceptibility, different histologic patterns, and clinical outcomes of H. pylori infection in Taiwan.

Dyspepsia↗
PubMed2000

In vitro and in vivo studies for modified ethyl cyanoacrylate regimens for sclerotherapy.

Cyanoacrylates have known for their ability to polymerize rapidly in the presence of traces of weakly basic moieties such as water. The tissue adhesive, Histoacryl(R) (N-butyl 2-cyanoacrylate), has been reported to control bleeding through endoscopic sclerotherapy. But the commercially available Histoacryl(R) is expensive, and it has the problem like other cyanoacrylates that the glue tends to flow/run away from the point of application, which is inherent to the low viscosity, making precise application difficult. In this study, ethyl cyanoacrylate (ECA), the main constituent of "super glue," was employed instead of Histoacryl(R) due to its lower cost. The aim of the research is to modify the compositions of ECA regimen and evaluate its feasibility for sclerosant application through both in vitro flow circuit model and in vivo animal tests. It was noted that the difference in the relative hardening rate between the in vitro Hepes-Tyrodes buffer flowing model and the in vivo rat model for the ECA and Histoacryl(R) was related to the existence of the blood protein, such as albumin, in the physiological milieu. It was also noticed that the ECA setting rate was greatly increased either in Hepes-Tyrodes buffer or in blood (to a comparable rate as Histoacryl(R) in vivo) by adding a few doses of caffeine, which acts as a polymerization initiator. This would lead to far better injection precision during sclerotherapy. Furthermore, in vivo histological examination for the occluded lumen of the rat's inferior vena cava and a clinical piglet portal vein occlusion experiment have suggested this new sclerosant regimen, caffeine/ECA, is of great promise in endoscopic sclerotherapy.

Animals↗
PubMed2000

Serologic response to lower-molecular-weight proteins of H. pylori is related to clinical outcome of H. pylori infection in Taiwan.

The study aimed to examine the serum serological response among H. pylori-infected patients with various upper gastrointestinal diagnoses; to ascertain whether it could be predictive to the diagnostic outcome of dyspepsia. One hundred seventy H. pylori-infected patients with dyspeptic symptoms but without previous treatment were enrolled, including those with duodenal ulcer disease (N = 47), gastric ulcer (N = 23), nonulcer dyspepsia (N = 60), gastric cancer (N = 34), and MALToma (N = 6). Sera from dyspeptic patients without H. pylori infection (N = 33) were used as controls. During endoscopy, gastric biopsies were taken for CLO-test, histology, and culture for the detection of H. pylori infection, defined by a positive culture or positive results of both CLO-test and histology. Total H. pylori IgG antibody was tested by an ELISA method. Antibody responses to specific H. pylori proteins were tested by a western blotting system. Of patients with H. pylori-infected gastroduodenal diseases, 76.5%, 42.9%, 23.6%, 46.7%, 84.1%, 76.5%, 82.9%, and 32.4% on average, showed responses to the 116-kDa (CagA), 89-kDa (VacA), 60-kDa, 45-kDa, 35-kDa, 30-kDa, 26.5-kDa, and 19.5-kDa H. pylori-specific proteins, respectively. A significant association was found between the serological response to 19.5-kDa and 26.5-kDa proteins and malignant outcome of H. pylori infection (P<0.02). Among patients without malignancy, the absence of a band at 19.5 kDa was statistically associated with the presence of an ulcer (P<0.05). The presence of serum antibody against CagA is not different between patients with ulcer and with malignancy in clinical diagnosis. The serum test for detecting antibodies against lower-molecular-weight proteins of H. pylori, such as those of 19.5 and 26.5 kDa, could be useful to identify H. pylori-infected patients at risk of peptic ulcer or malignancy.

Antibodies, Bacterial↗
PubMed2000

Saturated saline enhances the effect of electrochemical therapy.

We conducted this experiment to assess the effect of saline injection in electrochemical therapy. Platinum electrodes using direct current were inserted into egg white or liver parenchyma. Pure water or 0.9%, 3%, or 26% sodium chloride were injected into various objects to compare with the control group (no injection). Power was set at 10 V. In the egg-white experiment, gas bubbles and coagulated protein developed around the electrodes. In ex vivo liver, frothy reddish debris developed around the cathodes, while a hardening and shrunken surface occurred around the anodes. The pH was 14 around the cathodes, 0 around the anodes. The electric current, the amount of coagulated protein, and the severity of tissue damage were all in proportion to the concentrations of the injected saline. The volume destroyed in the 26% saline group was 8.1 times larger than that of the control group. Therefore, injected saline, especially saturated saline, can enhance the effect of electrochemical therapy.

Animals↗
PubMed2000

Selection of lower cutoff point of [13C]urea breath test is helpful to monitor H. pylori eradication after proton pump inhibitor-based triple therapy.

Our objectives were to test the efficacy of [13C] urea breath test (UBT) for H. pylori infection in patients before and after proton pump inhibitor (PPI) based triple therapy, and thus to trace the optimal cutoff value of UBT to monitor H. pylori eradication; and to analyze the histologic bacterial density and distribution of H. pylori in patients with equivocal UBT. A total of 441 dyspeptic cases patients enrolled and completed the study design, including 120 noninfected and 321 H. pylori-infected patients. All 441 cases had received the same protocol of UBT. in which the baseline and 15-min gas samples after ingestion of 100 mg 13C-labeled urea were analyzed for excess 13CO2/12CO2 ratio (ECR). In addition, a first endoscopy was performed in each patient to evaluate the initial status of H. pylori by culture and histology. Of the 321 H. pylori-infected patients, 286 received a second endoscopy and a second UBT six weeks after completing any one of four regimens of the PPI-based triple therapy to document the success of H. pylori eradication. During both sessions of endoscopy, topographic gastric biopsies for histology were sampled to evaluate the distribution and density of H. pylori. Based on the diagnostic standard by culture and histology, the sensitivity and specificity of the first UBT achieved most optimally was 97.5% and 96.7%, respectively, by setting the cutoff point of ECR at 4.0. In contrast, using the same cutoff point of 4.0, the sensitivity and specificity of the second UBT in patients after therapy achieved just 80% and 97.6%, respectively. By applying cutoff points downward of 4.0, 3.5, 3, and 2.5 for the second UBT, the sensitivity was elevated to 80%, 82.8%, 88.6%, and 94.3%, respectively, while the specificity was preserved at more than 95.2%. The overall eradication rate of H. pylori was 87.8% (251/286). Seven of 35 patients with failure of therapy had equivocal ECR at the second UBT (range 2-5), and this accounted for the false negative result. All seven patients had low bacterial densities, and three patients had bacteria distributed only in high body near the cardia. In conclusion, selection of a lower cutoff value of ECR at 2.5 is helpful to maintain the diagnostic accuracy of UBT for monitoring the H. pylori eradication. The equivocal ECR of UBT after therapy would be related to the low bacterial load and its distribution.

Adult↗
PubMed2000

Lower-dose (13)C-urea breath test to detect Helicobacter pylori infection-comparison between infrared spectrometer and mass spectrometry analysis.

BACKGROUND: The expense of the (13)C-urea breath test (UBT) to detect Helicobacter pylori infection is mainly due to the cost of (13)C-urea and the analysis using isotope ratio mass spectrometry (IRMS). AIM: To test whether a UBT, using a lower dose of urea and lower-priced isotope-selective nondispersive infrared spectrometry (INIS), can preserve diagnostic efficacy in clinical practice. METHODS: A total of 177 dyspeptic patients received endoscopy for H. pylori culture and histology. All of them received a UBT in which the duplicate baseline, 10 min, and 15 min breath samples after ingestion of 50 mg (13)C-urea were collected to analyse the excess (13)CO(2)/(12)CO(2) ratio (ECR) by IRMS (ABCA, Europa Scientific, UK) and INIS (UBiT-IR200, Photal Otsuka Electronics, Japan), respectively. RESULTS: Of the 177 patients, 84 were infected and 93 were uninfected with H. pylori. A close correlation of ECR was found between IRMS and INIS (r=0.9829 at 10 min; r=0.9918 at 15 min, P < 0.0001). Analysing the 15-min samples, UBT by both IRMS and INIS achieved the same sensitivity (96. 4%) and specificity (98.9%). CONCLUSIONS: INIS is as effective as IRMS for UBT, and can use a lower dose of (13)C-urea. This can provide an economic UBT, using the lower-priced INIS and a low dose of (13)C-urea.

Adult↗
PubMed2000

Human biliary beta-glucuronidase activity before and after relief of bile duct obstruction: is it the major role in the formation of pigment gallstones?

BACKGROUND AND AIMS: The bacterial beta-glucuronidase (bBG) can deconjugate conjugated bilirubin to form calcium bilirubinate gallstone. Yet, the role of the human biliary beta-glucuronidase (hBG) in the pathogenesis of pigment gallstone formation still remains unsolved. METHODS: Hepatic bile was collected from bile-duct-obstructed patients on the day of, and 3 days after, biliary drainage. Patients were divided into pigment-stone (PS) group (n = 34) and stone-free (SF) group (n = 29). All patients of the PS group had the complication of cholangitis. The concentrations of bile contents and the activities of bBG and hBG were measured. RESULTS: The activities of hBG and bBG in bile obtained on the day of biliary drainage were higher in the PS group than in the SF group (activities corrected for bile salt concentration: hBG 128.7 +/- 340.0 vs 13.1 +/- 25.0 U/mmol; bBG 12.5 +/- 22.2 vs 4.6 +/- 7.7 U/mmol, P < 0.05). This difference disappeared after biliary drainage. The changes of enzyme activity in the bile of the SF group were unremarkable before and after biliary drainage. The mean concentrations of bile pigments and free calcium in the PS group were lower than those in the SF group. CONCLUSIONS: An increase in the activity of hBG may be a secondary response, developed after bile duct inflammation because it was elevated only when the bile duct obstruction was associated with infection.

Bile↗
PubMed2000

Melatonin prevents pigment gallstone formation induced by bile duct ligation in guinea pigs.

Free radical-mediated oxidative stress has been implicated in the genesis of gallstone in vitro. This study was designed to examine the oxidative stress changes during pigment gallstone formation and to investigate whether melatonin (MLT) could act as a chemopreventive agent for cholelithiasis in a guinea pig model. The common bile duct of guinea pigs was ligated with or without MLT pretreatment. Animals were studied on day 7, 9, 12, and 14 after surgery. Stone and/or sludge developed in ligated guinea pigs without MLT. Fourier transform infrared spectra of the sludge showed the presence of calcium bilirubinate, whose peak height per milligram of sludge gradually increased with time after ligation. Total antioxidant activity (TAA) in bile of guinea pigs at day 14 after ligation reduced to one third of the level in sham-operated controls (P <.001). In addition, the bile of ligated guinea pigs had increased pH (P <.001), bile salts (P <.01), and malondialdehyde (MDA) (P <.05), compared to sham controls. Pretreatment of guinea pigs with MLT at a dose of 1,000 microg/kg significantly decreased the incidence of pigment gallstone formation at day 14 after ligation, as compared to no pretreatment (0/7 vs. 8/10). MLT also reverted the ligation-induced changes in biliary bile salts, pH, MDA, and TAA to control levels. These in vivo findings support a causative role of oxidative stress in the bile duct ligation-induced pigment gallstone formation. Antioxidants may prove useful in preventing pigment gallstone formation in humans.

Animals↗
PubMed2000

Carbon urea breath test is not as accurate as endoscopy to detect Helicobacter pylori after gastrectomy.

BACKGROUND: This study was conducted to determine (1) whether Helicobacter pylori infection decreases in conjunction with time elapsed after gastrectomy and (2) the diagnostic efficacy of (13)C urea breath test (UBT) for H pylori in patients after gastrectomy. METHODS: From January 1997 to June 1998, 86 patients who had undergone gastrectomy and 180 patients with dyspepsia without gastrectomy were enrolled. A UBT for the analysis of excess (13)CO(2)/(12)CO(2) ratio (ECR) was obtained for each patient. Each patient also underwent endoscopy to obtain gastric biopsies for histology and H pylori culture. The presence of H pylori by either histology or culture served as the standard to test the efficacy of UBT. The 86 patients with a prior gastrectomy were categorized into 3 subgroups (I, less than 1 year; II, 1 to 3 years; III, greater than 3 years), according to the interval between surgery and UBT. The initial H pylori status of these 86 patients was determined by histologic evaluation of the resected stomach. RESULTS: At trial initiation, the postgastrectomy group had a lower H pylori infection rate (52.3%) as compared with the dyspeptic control group (80%). The initial H pylori status among subgroups I, II, and III was similar. There was a trend for the presence of H pylori in the stomach to decrease with increasing time elapsed after surgery (I to III: 68.8%, 48.3%, 36%, respectively; p < 0.05). The maximum UBT sensitivity and specificity achieved were 82.2% and 87.8% in the gastrectomy group and 97.2% and 96.3% in the dyspeptic group, with cutoff points of 2.5 and 4.0, respectively. CONCLUSION: The prevalence of H pylori diminishes with time elapsed after gastrectomy. UBT for detection of H pylori is more effective in patients without prior gastrectomy than in patients who have undergone gastrectomy and is less effective than endoscopy for patients who have had a gastrectomy.

Biopsy↗
PubMed2000

Modified technique for introducer-type percutaneous endoscopic gastrostomy and jejunostomy: assisted by a novel trocar and fasteners.

BACKGROUND AND PURPOSE: Commercially available kits for percutaneous endoscopic gastrostomy (PEG) and jejunostomy comprise a substantial proportion of the cost of patients for this procedure. A modified introducer-type technique and new instrumentation for PEG and jejunostomy that substantially reduces the cost of the kit were tested for efficacy and safety. METHODS: This technique was tested on 10 pigs as a pilot study, and then applied to seven consecutive patients undergoing gastrostomy and three patients undergoing gastrostomy with jejunostomy. The endoscopy and site selection for gastrostomy were the same as in standard PEG. Two novel fasteners for fixing the gastric wall to the abdominal wall and a guide-wire in the selected site were inserted separately into the stomach through 15-gauge needles. A stainless steel trocar with a detachable sheath was introduced into the stomach over the guide-wire. After the inner stylet was removed, a 24-French Foley catheter was inserted as a feeding tube. Gastrostomy was completed after balloon inflation and external fixation. If jejunostomy was indicated, a 12-French nasogastric tube was inserted through the gastrostomy. The procedure time, complications, and costs were compared with those for another 15 consecutive patients who underwent the conventional pull-through method of PEG and jejunostomy using commercially available kits. RESULTS: No significant difference was found in procedure time between patients who underwent the modified or conventional gastrostomy procedures (mean +/- standard deviation, 15.4 +/- 5.6 min). There was a similar incidence of short-term complications in the two treatment groups. The feeding catheters required replacement more quickly than did those in the commercial kits (80 +/- 58 vs 217 +/- 140 d). The cost to patients was much less with the new method than with conventional PEG. CONCLUSIONS: The new gastrostomy method achieves the same medical quality at far less cost for patients.

Adult↗
PubMed2000

Impact of Helicobacter pylori antimicrobial resistance on the outcome of 1-week lansoprazole-based triple therapy.

PURPOSE: To determine the effect of Helicobacter pylori antimicrobial resistance on the efficacy of different proton pump inhibitor (PPI)-based triple therapies. METHODS: One-hundred and twelve dyspeptic patients with H. pylori infection, as demonstrated by positive histology and culture, were randomized to receive one of the three PPI-based triple therapies. The regimens included lansoprazole (L) plus any two of the following three antibiotics: amoxicillin (A), metronidazole (M), and clarithromycin (C); patients were allocated to ALC, MLC, and ALM subgroups. Six weeks after the start of triple therapy, the 13C-urea breath test (UBT) was performed to evaluate the success of H. pylori eradication. Patients with positive UBT results underwent endoscopy for H. pylori culture. The pre- and post-treatment H. pylori isolates were analyzed for initial and acquired resistance using the E-test. RESULTS: One hundred patients completed the study. The H. pylori eradication rates were 70% (21/30) in the ALM subgroups, 79% (26/33) in the MLC subgroup, and 89% (33/37) in the ALC subgroup. The frequencies of pretreatment H. pylori antimicrobial resistance were 0% for amoxicillin resistance (AR), 32% for metronidazole resistance (MR), and 6% for clarithromycin resistance (CR). For H. pylori isolates with initial MR, the eradication rates in the ALM (40%) and MLC (67%) subgroups were apparently lower than that in the ALC (92%) subgroup. In the ALM and MLC subgroups (i.e., patients who received metronidazole), the eradication failure rate was significantly higher for patients with MR isolates than for patients with metronidazole-susceptible isolates (47% vs 16%, p < 0.05). In the ALC and MLC subgroups (i.e., patients who received clarithromycin), the eradication failure rate was significantly higher for patients with CR isolates than for those with clarithromycin-susceptible isolates (100% vs 11%, p < 0.05). CONCLUSIONS: The results indicate that H. pylori antimicrobial resistance is relevant to the success of eradication. The high MR but low CR and AR prevalence among H. pylori isolates in this study suggests that PPI-based triple therapy including amoxicillin and clarithromycin may achieve the most favorable eradication rate.

2-Pyridinylmethylsulfinylbenzimidazoles↗
PubMed1999

Development of Helicobacter pylori infection model in BALB/c mice with domestic cagA-positive and -negative strains in Taiwan.

We aimed to develop an H. pylori-infected mouse model using clinically stored strains in Taiwan and to test whether development of H. pylori infection in an in vivo animal model is related to the status of the cagA gene. A total of 100 male BALB/c mice, 6-8 weeks old, including 80 in the experimental group and 20 in the control group, were used. Two clinically stored H. pylori isolates, a cagA-positive and a cagA-negative strain, were selected to induce the H. pylori infection in half (N = 40) of the mice in the experimental group. Bacterial isolates of 0.8 x 10(9) CFU/ml were orally inoculated in each mouse of the experimental group for three consecutive days. Ten mice in the control group were sacrificed to confirm the initial absence of H. pylori. Eight weeks after inoculation of the experimental group and no inoculation of the remaining 10 mice of the control group, each mouse was killed. Gastrectomy was then performed for rapid urease test (CLOtest) and histology. In the control group, none of 20 mice had positive results from the CLOtest or histology. In contrast, excluding eight of 80 mice that died before the eighth week, 90.3% (65/72) of the mice challenged with H. pylori showed persistent presence of H. pylori by histology. The severity of gastritis at the eighth week was more evident in H. pylori-infected mice than in control and noninfected mice (P < 0.05). Although gastritis was more severe in mice inoculated with the cagA-positive strain than with the cagA-negative strain, the rates of H. pylori infection in mice were not different between cagA-positive and -negative strains (91.4% vs 89.2%, P > 0.05). In summary, stored strains of H. pylori can be applied to induce an infection model in BALB/c mice. The less virulent cagA-negative strain can induce H. pylori infection in mice as effectively as the cagA-positive strain. The high prevalence of cagA-positive strains in Taiwanese patients may be related to factors other than only the cagA gene of the bacteria.

Animals↗