Helicobacter pylori and gut hormones

Helicobacter pylori infection has been found to decrease the expression of antral somatostatin and to increase the release of the acid-stimulating hormone gastrin. The reversal of these changes in gut hormones by the eradication of H. pylori, and in-vivo and in-vitro studies in animals either infected with H. pylori or exposed to H. pylori-related materials may support the somatostatin-gastrin link theory in the pathophysiology of H. pylori infection. The following mechanisms have been proposed to explain the H. pylori infection-associated changes in gut hormones; (1) ammonia produced by H. pylori and monochloramine, (2) effect on somatostatin receptor subtype-2, (3) action of lipopolysaccharide from H. pylori on somatostatin receptor, (4) inflammatory cells and mediators, and (5) bacterial strain diversity. H. pylori infection can alter gastric acid secretion in both directions. The elevated acid secretion in patients with duodenal ulcer is decreased by H. pylori eradication, and is accompanied by the normalization of gut hormones in patients whose H. pylori-induced gastritis is limited to the antrum with hyperacidity. Corpus gastritis and the subsequent development of mucosal atrophy induced by H. pylori result in decreased acid secretion, although the mechanism underlying H. pylori-induced atrophy in some subjects remains unclear. Hypoacidity enhances corpus atrophy and increases gastrin secretion, mediated via a physiological suppression of somatostatin release, features that are also observed in H. pylori infection. Therefore, the capacity of acid secretion and distribution of gastritis or atrophy should be taken into consideration when we discuss the affect of H. pylori on gut hormones. Received: October 1, 2001 / Accepted: November 30, 2001     

Radiofrequency catheter ablation within the coronary sinus eliminates a macro-reentrant atrial tachycardia: Importance of mapping in the coronary sinus

We describe a patient who underwent radiofrequency (RF) catheter ablation of symptomatic atrial fibrillation. After left atrial (LA) catheter ablation and pulmonary vein isolation, a macro-reentrant atrial tachycardia (AT) with a critical isthmus at the mitral isthmus was induced by incremental atrial pacing from the coronary sinus. Extensive RF energy applications from endocardial sites using ablation catheters with 4 mm- and 8 mm- tips resulted in no discrete potentials being recorded from the endocardial sites of the isthmus, but the tachycardia could not be terminated. However, discrete potentials were recorded within the CS, and epicardial RF energy applications from the CS eliminated the tachycardia. Thus, mapping in the CS is useful for detecting residual conduction at epicardial sites along the mitral isthmus. RF catheter ablation within the CS should be considered when no distinct electrograms are recorded after extensive ablation from the endocardial sites and when distinct electrograms are recorded within the CS.     

Early administration of fluvastatin, but not at the onset of ischemia or reperfusion, attenuates myocardial ischemia-reperfusion injury through the nitric oxide pathway rather than its antioxidant property.

BACKGROUND: Three-hydroxy-3-methylglutaryl-coenzyme A reductase inhibitors (statins) are known to attenuate myocardial ischemia-reperfusion (IR) injury. Fluvastatin (FV) has a potent free radical scavenging action, but it is unclear whether the timing of FV administration could affect its cardioprotective effect or if the antioxidant property of FV might attenuate IR injury. METHODS AND RESULTS: IR was induced in rats by left coronary artery occlusion for 30 min followed by 24-h reperfusion. The rats were divided into 4 groups: oral FV group (10 mg/kg per day for 2 weeks before ischemia); iv, FV group (10 mg/kg) before ischemia; iv, FV group (10 mg/kg) before reperfusion; and control group. Oxidative stress was evaluated by myocardial 8-hydroxydeoxyguanosine (8-OHdG) content. The area at risk did not different among the 4 groups. Pretreatment with FV for 2 weeks significantly reduced the infarct size by 28% as compared with the control group, but FV administered just before ischemia or reperfusion did not. Myocardial 8-OHdG content was not affected by FV. The infarct-sparing effect of FV was completely abolished by N(omega)-nitro-l-arginine methyl ester or wortmannin. CONCLUSIONS: The present results indicate that pretreatment with FV, but not just before ischemia or reperfusion, attenuates IR injury primarily through the nitric oxide pathway, not through its antioxidant property.     

Clinicopathologic features and prognostic factors of resected solitary small-sized hepatocellular carcinoma

BACKGROUND/AIMS: Solitary small-sized HCCs tend to be considered as less aggressive cancer, and non-surgical treatments have recently been preferred. The aim of this study was to clarify the clinicopathological features and the prognostic factors of small-sized HCCs and to evaluate the significance of hepatic resection for them. METHODOLOGY: Eighty patients with HCC up to 2cm in diameter who had undergone hepatic resection were enrolled in this study. We investigated the clinicopathological features and evaluated the prognostic factors by univariate and multivariate analyses. RESULTS: The overall survival rates at 3, 5 and 10 years were 83%, 69% and 36%, respectively, and the corresponding disease-free survival rates were 63%, 41% and 10%. Well-differentiated, moderately differentiated and poorly differentiated HCC were detected in 29%, 65% and 6% of the patients, respectively. Furthermore, microscopic portal vein invasion (vp), hepatic vein invasion (vv) and intrahepatic metastasis (im) were positive in 15%, 4% and 10% of the patients, respectively. Multivariate analysis revealed that Child-Pugh classification (p=0.005) and vp (p=0.0008) were independent prognostic factors for survival rate and that platelet count (p=0.002) and tumor differentiation (p=0.0016) were independent prognostic factors for disease-free survival rate. CONCLUSIONS: Even solitary small-sized (up to 2cm in diameter) HCC already have the characteristics of advanced HCC. When hepatic function is well preserved, hepatic resection should be the first choice for local control, especially in cases of moderately to poorly differentiated HCC, because the frequency of microscopic vascular invasion is high.     

Elucidation of conditions allowing conversion of penicillin G and other penicillins to deacetoxycephalosporins by resting cells and extracts of Streptomyces clavuligerus NP1

Using resting cells and extracts of Streptomyces clavuligerus NP1, we have been able to convert penicillin G (benzylpenicillin) to deacetoxycephalosporin G. Conversion was achieved by increasing by 45× the concentration of FeSO₄ (1.8 mM) and doubling the concentration of α-ketoglutarate (1.28 mM) as compared with standard conditions used for the normal cell-free conversion of penicillin N to deacetoxycephalosporin C. ATP, MgSO₄, KCl, and DTT, important in cell-free expansion of penicillin N, did not play a significant role in the ring expansion of penicillin G by resting cells or cell-free extracts. When these conditions were used with 14 other penicillins, ring expansion was achieved in all cases.     

Increased Levels of Human Hepatocyte Growth Factor in Serum and Peritoneal Fluid After Partial Hepatectomy

Objective/Method : It has been reported that inflammatory cytokines up-regulate human hepatocyte growth factor synthesis in vitro. lo demonstrate the relation of this growth factor to interleukin-6 and tumor necrosis factor a, the changes in the levels of these cytokines were measured in serum and peritoneal fluid in 22 patients after partial hepatectomy. Results : Serum and fluids levels of cytokines showed a maximum within 3 days after surgery. Cytokines concentrations were much higher in fluid than in serum (p < 0.05). The maximum serum levels of human hepatocyte growth factor were significantly correlated with those of interleukin-6, intraoperative blood loss, and operating time (p < 0.05) but not with resected liver weights. In fluid level, the growth factor was also correlated with interleukin-6 (p < 0.05) but not with tumor necrosis factor α. Conclusions : These results suggest that human hepatocyte growth factor might be locally produced in the injured tissue associated with interleukin-6 and independently of resected liver weights.     

Antimicrobial susceptibilities of Streptococcus pneumoniae and Haemophilus influenzae isolated from children with meningitis

Between April 2001 and March 2003, we studied minimum inhibitory concentrations (MIC) and minimum bactericidal concentrations (MBC) of 7 strains of Streptococcus pneumoniae and 8 strains of Haemophilus influenzae isolated from children with meningitis. The age range of the patients was from 4 months to 5 years. Susceptibilities of ampicillin (ABPC), cefotaxime (CTX), panipenem (PAPM), and vancomycin (VCM) in S. pneumoniae and those of ABPC, CTX, ceftriaxone (CTRX), and meropenem (MEPM) in H. influenzae were measured. MICs of ABPC, CTX, PAPM, and VCM to S. pneumoniae were < or = 0.06-2, < or = 0.06-0.5, < or = 0.06, and 0.25-0.5 microgram/ml and MICs of ABPC, CTX, CTRX, and MEPM to H. influenzae were 0.12-64, < or = 0.06-0.5, < or = 0.06-0.12, and < or = 0.06-0.25 microgram/ml, respectively. In 5 of all strains, difference between MIC and MBC to ABPC was observed. Four strains out of them had mutations of penicillin binding protein genes measured by PCR methods.     

Massive mesenteric edema in a patient with type I hereditary angioedema

We report a patient with hereditary angioedema (HAE) presenting with skin edema and abdominal pain. Laboratory examination showed reduced levels of CH50, C2, C4, and C1 inhibitor (C1-INH). Abdominal computed tomography (CT) showed marked mesenteric edema and wall thickening of the duodenum and transverse colon. Acute abdominal pain is common in HAE and is difficult to distinguish from surgical emergency. Massive mesenteric edema on CT is a rare, but specific, sign suggesting HAE.     

Assessment of MEF2A mutations in myocardial infarction in Japanese patients.

BACKGROUND: Recently, a mutation in the human MEF2A gene was reported to be responsible for an autosomal dominant form of coronary artery disease, so the purpose of the present study was to assess the significance of MEF2A mutations in Japanese subjects with myocardial infarction (MI). METHODS AND RESULTS: The study population consisted of 589 control subjects recruited from the Suita study and 379 subjects with MI. The promoter, all the exons, and 3'-UTR regions of MEF2A were sequenced in 190 subjects with myocardial infarction. We found 2 amino acid length polymorphisms, a 7-amino acid deletion polymorphism, and a nonsense mutation (R447X) in exon 12. The length and deletion polymorphisms did not confer susceptibility to MI. Although the nonsense mutation was detected in 1 subject with MI, and in none of the control subjects, the impact of this mutation does not appear to be great; the subject had the MI while in his 70 s, had 2 major risk factors, and no family history of ischemic heart disease. CONCLUSION: MEF2A polymorphism does not contribute appreciably to MI in the Japanese population.     

Relationship between dominant prolongation of the filtered QRS duration in the right precordial leads and clinical characteristics in Brugada syndrome

Background: Electrical abnormalities in the RVOT may be involved in Brugada syndrome.
Objectives: We investigated the relationship between the signal-averaged ECG (SAECG) and electrophysiologic study (EPS), especially focusing on conduction delay in the outflow tract of the right ventricle (RVOT) and its contribution to clinical characteristics.
Methods: Twenty-four patients with Brugada syndrome (23 men and 1 woman; 61 ± 16 years old) were studied. We assessed the presence of late potential (LP) in SAECG and the filtered QRS duration in the right precordial leads (V₁ or V₂; RfQRS) and in the left precordial leads (V₅ or V₆; LfQRS) and the difference between them. In 18 patients, SAECG was evaluated for an LP on three separate occasions.
Results: SAECG was positive for LP in 15 patients at least once; and in 7 patients, SAECG was positive for an LP on multiple occasions, and 6 of 7 patients (86%) had a history of cardiac arrest. The difference between RfQRS and LfQRS was significantly greater in patients with cardiac arrest than in patients with syncope or in asymptomatic patients; 29 ± 10, 14 ± 11 (P < 0.01), and 7 ± 5 msec (P < 0.001), respectively. All patients were alive and one patient with cardiac arrest had an appropriate VF therapy delivered by the ICD.
Conclusions: The dominant prolongation of the filtered QRS duration in the right precordial leads may be related to the risk of arrhythmic event in Brugada syndrome.