Nonconjugative Plasmids Encoding Sulfanilamide Resistance

Nonconjugative plasmids encoding sulfanilamide (Sa) resistance were demonstrated at a high frequency in Shigella and Escherichia coli strains resistant to sulfanilamide. These Sa plasmids were all compatible with the standard plasmids used in compatibility testing. The sizes of seven Sa plasmids were measured by electron microscopy and ranged from 1.79 to 2.08 mum, corresponding to 3.5 to 3.9 megadaltons.     

Genetic differences in CYP2C19 single nucleotide polymorphisms among four Asian populations

Background. This study was designed to compare genetic differences in single-nucleotide polymorphisms of the S-mephenytoin 4′-hydroxylation (CYP2C19) gene among four Asian populations. Methods. Polymerase chain reaction with restriction fragment length polymorphism (PCR-RFLP) analysis of CYP2C19 was conducted in Japanese, Chinese, Thai, and Vietnamese populations. All genotype frequencies were analyzed. Wild-type homozygote and wild-type heterozygote genotypes were extensive proton pump inhibitor (PPI) metabolizers. Mutant-type heterozygote and mutant-type homozygote genotypes were poor PPI metabolizers. Results. No significant differences in CYP2C19 phenotype, calculated based on genotype frequencies, (P > 0.05) were found among the four populations. Conclusions. Many factors, including CYP2C19 polymorphisms, affect the success rate of Helicobacter pylori eradication with PPI-based therapy. We suspect that CYP2C19 polymorphisms may not be the main factor associated with differences among these four Asian populations in the success rates of H. pylori eradication with PPI-based therapy. Received: October 10, 2000 / Accepted: April 13, 2001     

Landiolol for junctional ectopic tachycardia refractory to amiodarone after pediatric cardiac surgery

Postoperative junctional ectopic tachycardia (JET) in children undergoing cardiac surgery is a serious arrhythmia that is associated with considerable morbidity and mortality. We present here a case of successful landiolol therapy for postoperative JET in a 3-month-old infant who underwent ventricular septal defect closure and right pulmonary artery plasty. His left ventricular function was poor postoperatively. The JET was refractory to amiodarone and caused severe hypotension, which was required cardiac massage. Continuous intravenous infusion of low-dose landiolol reduced the persistent JET rate immediately, and restored to sinus rhythm with stable hemodynamics.     

Tissue characterization identifies subjects with high risk of cardiovascular diseases

OBJECTIVE: This study was conducted to examine whether tissue characterization of the carotid artery wall by determining integrated backscatter (IBS) can identify subjects with a recent history of acute coronary syndrome (ACS) or atherothrombotic infarction (ATI). RESEARCH DESIGN AND METHODS: The maximum thickness (Max-IMT) and IBS value (corrected-IBS) of the carotid artery intima-media complex were measured ultrasonographically for 132 type 2 diabetic subjects (62.9+/-8.5 (+/-S.D.) years old, 87 men and 45 women) with or without cardiovascular diseases. RESULTS: The diabetic patients with recent ACS or ATI had a significantly lower corrected-IBS and higher Max-IMT than those with Max-IMT > or = 1.1mm but without cardiovascular diseases. The product of Max-IMT and corrected-IBS (IMT-IBS product) of the patients with recent ACS was significantly lower than that of the patients with chronic stable angina. The multiple logistic model showed that only the IMT-IBS product was associated with a recent history of ACS (odds ratio 0.94, P<0.05) and ATI (odds ratio 0.90, P<0.005). CONCLUSIONS: Diabetic patients who had a recent history of ACS or ATI showed a lower IBS value and higher IMT for their carotid artery. Both the size and tissue characteristics of the carotid plaque may identify subjects with a high risk of cardiovascular disease.     

Heart rate elevation and diabetic retinopathy in patients with type 2 diabetes mellitus and normoalbuminuria

To investigate the role of heart rate (HR) and blood pressure (BP) for diabetic retinopathy, 24-h ambulatory HR and BP were monitored for 162 in patients with type 2 diabetes and normoalbuminuria. The fundus was assessed as no retinopathy, simple diabetic retinopathy (SDR) and proliferative retinopathy (PDR). Comparing the highest with the lowest quartile of diabetic duration, the relative risk for retinopathy was 9.3 and for nocturnal HR, it was 3.6. Comparison among three retinopathy groups (no retinopathy, group 1, n=122; SDR, group 2, n=24; Pre-PDR or PDR, group 3, n=16) showed that 24-h and nocturnal HR were significantly higher in group 3 (80+/-9 and 71+/-9 beats per min) than in group 2 (73+/-8 and 64+/-8) and group 1 (72+/-7 and 60+/-7). In multiple logistic analysis, the odds ratio of diabetic duration and nocturnal HR to the existence of retinopathy was 1.17 (95% CI, 1.10-1.25, P=0.00001) and 1.11 (95% CI, 1.05-1.17, P=0.0002). We concluded that diabetic retinopathy is related to diabetic duration and high heart rate in type 2 diabetes mellitus with normoalbuminuria. Heart rate elevation may be a predictor of advanced retinopathy.     

Differentiation between late potentials of right ventricular and of left ventricular origin

The aim of this study was to determine whether late potentials of right and left ventricular origin could be differentiated with the use of a signal-averaging technique. Nineteen patients with both late potentials and recurrent sustained ventricular tachycardia were divided into 2 groups according to the origin of their late potentials. Group I consisted of 10 patients with late potentials that originated from the right ventricle. Group II consisted of 9 patients with late potentials originating from the left ventricle. Signal-averaged electrocardiograms (Marquette Electronics MAC I unit) were recorded using 3 bipolar and 3 augmented unipolar leads (the electrode positions were V1, V5 and V6R) with a band-pass filter of 100 to 300 Hz. The augmented unipolar V5 lead (aV5) was used for left-side recording and the augmented unipolar V1 lead (aV1) was used for right-side recording. In group I, the mean maximal late potential amplitude was larger in lead aV1 than in lead aV5 (5.1 +/- 2.5 vs 3.7 +/- 1.8 microV, p less than 0.005) and the maximal late potential amplitude was larger in lead aV1 in all except 1 patient. In group II, however, the mean maximal late potential amplitude was smaller in lead aV1 than in lead aV5 (4.0 +/- 3.0 vs 5.7 +/- 3.2 microV, p less than 0.005) and the maximal late potential amplitude was smaller in lead aV1 in all patients. Thus, the origin of late potentials (right ventricular vs left ventricular origin) can be determined by comparing the maximal amplitudes of late potentials in the right- and left-sided leads. This method might be useful in determining ventricular tachycardia origins.     

Relation between the widening of the fragmented atrial activity zone and atrial fibrillation

Fragmented electrical activity is often recorded by a local atrial electrogram in response to atrial extrastimuli. To assess the relation between fragmented activity and the spontaneous occurrence of atrial fibrillation or flutter (AFF), the fragmented activity zone was measured in 57 patients. The electrograms of the high right atrium, low right atrium and left atrium (through the coronary sinus) were recorded simultaneously during high right atrial stimulation. The fragmented activity zone was defined as the S₁–S₂ interval (S₁ = stimulus of a basic beat, S₂ = stimulus of a premature beat) during which a significant fragmented activity was recorded by a high right atrial electrogram after S₂. Fifteen patients had neither sinoatrial disease nor atrial arrhythmias (Group I, controls), 16 had sick sinus syndrome (SSS) with a history of paroxysmal AFF (Group II), 14 had SSS without a history of paroxysmal AFF (Group III), and 12 had idiopathic paroxysmal AFF (Group IV). The fragmented activity zone was significantly wider in Group II (112 ± 26 ms [mean ± standard deviation], p < 0.001), Group III (77 ± 38 ms, p < 0.001) and Group IV (86 ± 19 ms, p < 0.001) than in Group I (31 ± 25 ms). Patients in Group II had a wider fragmented activity zone than those in Group III (p < 0.01). Thus, the widening of the fragmented atrial activity zone is characteristic of AFF and may be a good index of a tendency to develop spontaneous AFF.     

Compression of an anomalous single coronary artery from pulmonary artery by banding

This report describes a case with double outlet right ventricle and doubly committed ventricular septal defect associated with congenital diaphragmatic hernia. The patient underwent pulmonary artery banding and clipping of patent ductus arteriosus after repair of the diaphragmatic hernia. At 6 months, cardiac catheterization revealed anomalous origin of a single coronary artery from the pulmonary artery of the proximal banding. Although ischaemic symptoms had not been observed, the banding had resulted in compression of the coronary ostium. An emergency Rastelli procedure with Damus-Kaye-Stansel anastomosis was successfully performed.     

Adiponectin G276T gene polymorphism is associated with cardiovascular disease in Japanese patients with type 2 diabetes

ObjectiveAdiponectin has anti-atherogenic properties and reduced serum adiponectin levels are associated with cardiovascular disease (CVD). In this study, we examined the relationship between CVD and adiponectin (ADIPOQ) gene G276T polymorphism that is associated with serum adiponectin level in a large cohort of type 2 diabetic patients.Research design and methodsWe enrolled 2637 Japanese type 2 diabetic subjects (males, 61.1%; age, 54.9 ± 7.9 years old), determined their genotypes regarding ADIPOQ G276T polymorphisms, and evaluated the association between this polymorphism and the prevalence of CVD (myocardial infarction and/or cerebral infarction).ResultsThe prevalence of CVD tended to be higher as the number of G alleles increased [GG (9.5%), GT (6.8%), TT (5.6%), p value for trend = 0.0059] and was significantly higher in the subjects with GG genotype compared to those with GT or TT genotype (9.5% vs. 6.6%, p = 0.0060). Multiple logistic regression analyses revealed that the number of G alleles (Odds ratio (OR) = 1.49 with 95%CI 1.09–2.05, p = 0.0125) and GG genotype (OR = 1.66 with 95%CI 1.13–2.43, p = 0.0098) were significantly associated with CVD even after adjustment for conventional risk factors. Interestingly, the presence of obesity further and significantly increased the risk of CVD in the subjects with GG genotype (OR = 1.67 with 95%CI 1.14–2.44, p = 0.0090) but not in the subjects with TT or GT genotype (OR = 1.17 with 95%CI 0.73–1.89, NS).ConclusionsIt is likely that the G allele of the ADIPOQ G276T polymorphism is a susceptibility allele for CVD in Japanese type 2 diabetic patients, especially when they accompany obesity.