Retinoic acid-inducible gene-I (RIG-I) is induced by IFN-{gamma} in human mesangial cells in culture: possible involvement of RIG-I in the inflammation in lupus nephritis

Interferon-gamma is a potent Th1-type cytokine and a key molecule in the pathogenesis of autoimmune diseases including lupus nephritis. Retinoic acid-inducible gene-I is a putative RNA helicase that plays an important role in immune and inflammatory reactions. We previously demonstrated the increased expression of the retinoic acid-inducible gene-I protein in the kidney tissue of patients with lupus nephritis, and the presence of a significant amount of retinoic acid-inducible gene-I mRNA in the urinary sediment of patients with this inflammatory renal disease. In the present study, interferon-gamma was found to induce the expression of retinoic acid-inducible gene-I in human mesangial cells in culture. Knockdown of retinoic acid-inducible gene-I inhibited the interferon-gamma-induced upregulation of interferon regulatory factor 7, a transcriptional factor involved in immune and inflammatory reactions. These findings suggest that retinoic acid-inducible gene-I produced by mesangial cells may be involved in the pathogenesis of lupus nephritis.

Association of the Jun dimerization protein 2 gene with intracranial aneurysms in Japanese and Korean cohorts as compared to a Dutch cohort

In a previous study a linkage region for association to IA patients was found on chromosome 14q22. In this study, we report the findings of a positional candidate gene, Jun dimerization Protein 2 (JDP2), and single nucleotide polymorphisms (SNP) of that gene that are associated with intracranial aneurysms in different ethnic populations. We screened the linkage region around chromosome 14q22 and narrowed it down to JDP2. We then genotyped case and control groups of three different ethnic populations: 403 Japanese intracranial aneurysm (IA) cases and 412 controls, 181 Korean IA cases and 181 controls, 379 Dutch cases and 642 Dutch controls. Genotyping was performed using polymerase chain reaction and direct sequencing technology. The allele distribution of three SNPs (two intronic: rs741846; P=0.0041 and rs175646; P=0.0014, and one in the untranslated region: rs8215; P=0.019) and their genotype distribution showed significant association in the Japanese IA patients. The allelic and genotypic frequency of one intronic SNP (rs175646; P=0.0135 and P=0.0137, respectively) and the genotypic frequency for the SNP in the UTR region (rs8215; P=0.049) was also significantly different between cases and controls of the Korean cohort. There was no difference in allelic or genotypic frequencies in the Dutch population. These SNPs in JDP2 are associated with intracranial aneurysms, suggesting that variation in or near JDP2 play a role in susceptibility to IAs in East Asian populations.

Positional effects of polymorphisms in probe-target sequences on genoplot images of oligonucleotide microarrays

Single nucleotide polymorphisms (SNPs) present in probe-target sequences (SPTS) have been shown to be associated with abnormal genoplot images. We explored the effects of SPTS positions on genoplot images using a data set from a genome-wide association study typed on an Illumina Human Hap300 platform. We screened the physical genomic positions of 308,330 autosomal probes to identify SPTS candidates deposited in dbSNP. The genoplot images across 293 individuals were inspected further in SNPs bearing an SPTS candidate. We identified 35,185 SNPs bearing a single SPTS candidate, including 264 SNPs showing abnormal genoplot images. The frequencies of SPTS at distances within 10 bases from the target SNP were significantly higher in the 264 SNPs showing abnormal genoplot images, than in the remaining 34,921 SNPs (49.62 vs 12.87%; Fisher exact test; P = 2.2 x 10(-16)). Of these 264 SNPs, we randomly selected 20 SNPs and resequenced them in 97 individuals. An SPTS within 10 bases of the target SNP was confirmed in all 20 SNPs, except for one SNP with a small deletion (7 bases) in the probe-target sequence. Taken together, these results suggest an association of a proximal SPTS with an abnormal genoplot image, which could result in spurious genotype detections, highlighting the importance of minimizing systematic errors in microarray experiments.

De novo mutations of voltage-gated sodium channel alphaII gene SCN2A in intractable epilepsies

BACKGROUND

Mutations of voltage-gated sodium channel alpha(II) gene, SCN2A, have been described in a wide spectrum of epilepsies. While inherited SCN2A mutations have been identified in multiple mild epilepsy cases, a de novo SCN2A-R102X mutation, which we previously reported in a patient with sporadic intractable childhood localization-related epilepsy, remains unique. To validate the involvement of de novo SCN2A mutations in the etiology of intractable epilepsies, we sought to identify additional instances.

METHODS

We performed mutational analyses on SCN2A in 116 patients with severe myoclonic epilepsy in infancy, infantile spasms, and other types of intractable childhood partial and generalized epilepsies and did whole-cell patch-clamp recordings on Na(v)1.2 channels containing identified mutations.

RESULTS

We discovered 2 additional de novo SCN2A mutations. One mutation, SCN2A-E1211K, was identified in a patient with sporadic infantile spasms. SCN2A-E1211K produced channels with altered electrophysiologic properties compatible with both augmented (an approximately 18-mV hyperpolarizing shift in the voltage dependence of activation) and reduced (an approximately 22-mV hyperpolarizing shift in the voltage dependence of steady-state inactivation and a slowed recovery from inactivation) channel activities. The other de novo mutation, SCN2A-I1473M, was identified in a patient with sporadic neonatal epileptic encephalopathy. SCN2A-I1473M caused an approximately 14-mV hyperpolarizing shift in the voltage dependence of activation.

CONCLUSIONS

The identified de novo mutations SCN2A-E1211K, -I1473M, and -R102X indicate that SCN2A is an etiologic candidate underlying a variety of intractable childhood epilepsies. The phenotypic variations among patients might be due to the different electrophysiologic properties of mutant channels.

History of diabetes mellitus as a neurologic predictor in comatose survivors of cardiac arrest of cardiac origin treated with mild hypothermia

AIM

To investigate the impact of a history of diabetes mellitus on the neurologic outcome in comatose survivors of cardiac arrest of cardiac origin treated with mild hypothermia.

METHODS

A prospective observational study was performed between September 2003 and July 2008. Eighty comatose survivors of cardiac arrest of cardiac origin were treated with mild hypothermia. Neurologic outcome at the time of hospital discharge, 30-day survival, and complications were assessed.

RESULTS

Twenty-four of the 80 patients (30%) had a history of diabetes. The rate of favorable neurologic outcome was significantly lower in diabetic (17%) than in nondiabetic patients (46%) (p=0.01). The rate of 30-day survival was lower in diabetic (33%) than in nondiabetic patients (54%), but the difference was not significant (p=0.10). Multivariate analysis suggested that a history of diabetes was an independent predictor of unfavorable neurologic outcome (odds ratio 7.00, 95% confidence interval 1.42-46.19, p=0.03), but not for 30-day survival. There was no significant difference in the prevalence of complications.

CONCLUSION

A history of diabetes is associated with poor neurologic outcome in comatose survivors of cardiac arrest treated with mild hypothermia.

The decrease in QRS amplitude after aortic valve replacement in patients with aortic valve stenosis

PURPOSE

The purpose of this study was to evaluate the effect of aortic valve replacement on electrocardiogram (ECG) in patients with aortic valve stenosis.

METHODS

Serial 12-lead ECGs were obtained in 15 patients with aortic valve stenosis who underwent aortic valve replacement. Three ECG indexes for left ventricular hypertrophy were manually measured in each ECG: Sokolow-Lyon index (sum of S wave in V(1) and R wave in V(5)), Cornell voltage index (sum of R wave in aVL and S wave in V(3)), and Gubner index (sum of R wave in I and S wave in III).

RESULTS

After aortic valve replacement, Sokolow-Lyon index gradually decreased during 2 years (51.1 +/- 17.9 to 34.8 +/- 12.5 mm, P < .01). Cornell voltage index (25.6 +/- 7.0 to 15.0 +/- 4.8 mm, P < .01) and Gubner index (15.8 +/- 7.6 to 10.3 +/- 5.5 mm, P < .01) also gradually decreased during 2 years. ST depression in V(6) was found in 14 patients (93%) before aortic valve replacement. It resolved in 9 of 14 patients during 2 years.

CONCLUSIONS

Electrocardiographic evidence of left ventricular hypertrophy gradually resolved after aortic valve replacement in patients with aortic valve stenosis.

Gene-expression profiles in human nasal polyp tissues and identification of genetic susceptibility in aspirin-intolerant asthma

BACKGROUND

Aspirin-intolerant asthma (AIA) is a subtype of asthma induced by non-steroidal anti-inflammatory drugs and characterized by an aggressive mucosal inflammation of the lower airway (asthma) and the upper airways (rhinitis and nasal polyp). The lower airway lesion and the nasal polyp in AIA are postulated to have common pathogenic features involving aspirin sensitivity that would be reflected in the gene expression profile of AIA polyps.

OBJECTIVE

This study was conducted to clarify the pathogenesis of AIA using gene expression analysis in nasal polyps, and identify genetic susceptibilities underlying AIA in a case-control association study.

METHODS

Global gene expression of nasal polyps from nine AIA patients was examined using microarray technology in comparison with nasal polyps from five eosinophilic sinusitis (ES) patients, a related disease lacking aspirin sensitivity. Based on the AIA-specific gene expression profile of nasal polyp, candidate genes for AIA susceptibility were selected and screened by a case-control design of 219 AIA patients, 374 non-asthmatic control (CTR), and 282 aspirin-tolerant asthmatic (ATA) subjects.

RESULTS

One hundred and forty-three elevated and three decreased genes were identified as AIA-specific genes that were enriched in immune response according to Gene Ontology analysis. In addition, a k-means-based algorithm was applied to cluster the genes, and a subclass characteristic of AIA comprising 18 genes that were also enriched in immune response was identified. By examining the allelic associations of single nucleotide polymorphisms (SNPs) of AIA candidate genes relevant to an immune response with AIA, two SNPs, one each of INDO and IL1R2, showed significant associations with AIA (P=0.011 and 0.026 after Bonferroni's correction, respectively, in AIA vs. CTR). In AIA-ATA association analysis, modest associations of the two SNPs with AIA were observed.

CONCLUSION

These results indicate that INDO and IL1R2, which were identified from gene expression analyses of nasal polyps in AIA, represent susceptibility genes for AIA.

Right atrial thrombosis after upgrading to a biventricular pacing/defibrillation system

A 56-year-old man under right ventricular pacing for atrial fibrillation and bradycardia had congestive heart failure. He received a cardiac resynchronization pacemaker with a defibrillator. Four months later, follow-up transthoracic echocardiography showed a right atrial mass although he had no symptom. Transesophageal echocardiography showed a large immobile round-shaped mass on the defibrillation lead, which was attached to the free wall of the right atrium. One month after the initiation of anticoagulant therapy, the mass disappeared, suggesting that it was thrombotic. During the 5 month follow-up, he remained in good condition without the recurrence of right atrial thrombosis.

The anaphase promoting complex targeting subunit Ama1 links meiotic exit to cytokinesis during sporulation in Saccharomyces cerevisiae

Ascospore formation in yeast is accomplished through a cell division in which daughter nuclei are engulfed by newly formed plasma membranes, termed prospore membranes. Closure of the prospore membrane must be coordinated with the end of meiosis II to ensure proper cell division. AMA1 encodes a meiosis-specific activator of the anaphase promoting complex (APC). The activity of APC(Ama1) is inhibited before meiosis II, but the substrates specifically targeted for degradation by Ama1 at the end of meiosis are unknown. We show here that ama1Delta mutants are defective in prospore membrane closure. Ssp1, a protein found at the leading edge of the prospore membrane, is stabilized in ama1Delta mutants. Inactivation of a conditional form of Ssp1 can partially rescue the sporulation defect of the ama1Delta mutant, indicating that an essential function of Ama1 is to lead to the removal of Ssp1. Depletion of Cdc15 causes a defect in meiotic exit. We find that prospore membrane closure is also defective in Cdc15 and that this defect can be overcome by expression of a form of Ama1 in which multiple consensus cyclin-dependent kinase phosphorylation sites have been mutated. These results demonstrate that APC(Ama1) functions to coordinate the exit from meiosis II with cytokinesis.

Trends in gender difference in mortality after acute myocardial infarction

BACKGROUND

Progress in management of acute myocardial infarction (AMI) might have changed the effect of gender on mortality.

METHODS

From May 1981 to November 2002, 1984 consecutive patients with AMI underwent emergency coronary angiography. They were divided into three groups in chronological order: group I (1981-1988, n=564); group II (1989-1995, n=678); and group III (1997-2002, n=742). Multi-variable analysis was performed using Cox's proportional hazard regression, adjusting baseline clinical and angiographical variables.

RESULTS

There were 405 women (20%). Thrombolysis was most frequently performed in group I (50%), balloon angioplasty in group II (71%), and stent in group III (66%), with no difference in the allocation of reperfusion therapy between men and women. Three-year mortality was significantly higher in women than in men in group I (27% vs 18%, p=0.03) and group II (23% vs 15%, p=0.048). In group III, there was no significant difference in 3-year mortality (12% vs 10%, p=0.66) between women and men. Women were associated with higher age, more diabetes, more hypertension, fewer current smokers, and less previous infarction than men. Multi-variable analysis showed that sex was not an independent predictor of 3-year mortality in the three groups.

CONCLUSIONS

Women with AMI who were treated mostly with primary intervention using stent in the contemporary era had similar mortality to men.

Torsade de pointes associated with bradycardia and takotsubo cardiomyopathy

Two cases of torsade de pointes associated with bradycardia and takotsubo cardiomyopathy are reported. In both cases, atrioventricular block preceded the occurrence of takotsubo cardiomyopathy. Bradycardia-induced QT interval prolongation seemed to be amplified by the occurrence of takotsubo cardiomyopathy, resulting in torsade de pointes. Temporary ventricular pacing at a high rate decreased the QT interval and prevented the recurrence of torsade de pointes. Because atrioventricular block recurred or persisted even after the resolution of takotsubo cardiomyopathy, the patients received permanent pacemakers.