Specific detection of Entamoeba histolytica DNA by hemolysin gene targeted PCR

Diagnostic differentiation of pathogenic Entamoeba histolytica from non-pathogenic Entamoeba dispar is of great clinical importance. We have developed and evaluated a new polymerase chain reaction (PCR) assay (haemo-PCR) based on the novel E. histolytica hemolysin gene HLY6. The specificity of this assay was confirmed by analyzing different Entamoeba species, faeces samples, human and bacterial DNA, and digestion of amplification products with appropriate restriction enzymes. The sensitivity was confirmed by serial dilutions of E. histolytica HM-1:IMSS DNA in the excess of human DNA. Totally, 45 clinical samples were analyzed by the haemo-PCR assay including amoebic liver abscess (ALA) fluids from 23 patients suspected for amoebiasis, four faeces samples containing E. histolytica and E. dispar, and positive and negative controls. The results were compared with those obtained with PCRs for cystein-rich surface protein (P30) and small subunit ribosomal RNA (ssu rRNA) genes. The haemo-PCR gave a positive result in 18 (89%) ALA fluids compared with 14 (77%) and five (28%) by PCR for p30, and ssu rRNA, respectively. PCR products were obtained only from specimens containing E. histolytica DNA. The haemo-PCR assay was therefore found to be a valuable diagnostic tool for identification of E. histolytica infections both in faeces and ALA samples.     

Juvenile rheumatoid arthritis and asthma,but not childhood-onset systemic lupus erythematosus are associated with FCRL3 polymorphisms in Mexicans

A regulatory single nucleotide polymorphism located in the 5′ region (?169T/C) of the Fc receptor-like 3 (FCRL3_3) gene has been associated with both susceptibility and protection in immune diseases. This case–control study aimed to evaluate the association between FCRL3 polymorphisms and juvenile rheumatoid arthritis (JRA), asthma, and childhood-onset systemic lupus erythematosus (SLE) in a Mexican population. We performed PCR-based genotyping to identify four FCRL3 single nucleotide polymorphisms (FCRL3_3 to FCRL3_6) in patients with JRA (n = 202), asthma (n = 239), or childhood-onset SLE (n = 377), and healthy controls (n = 400). The case–control analysis showed a male-gender dependent association between the FCRL3_3C, FCRL3_5C, and FCRL3_6A alleles and either JRA (OR = 0.57, p = 0.003; OR = 0.55, p = 0.002; OR = 0.53, p = 0.0007, respectively) or asthma (OR = 0.72, p = 0.04; OR = 0.74, p = 0.05; OR = 0.70, p = 0.02, respectively). As expected, minor alleles of these SNPs with the CGCA haplotype were also significantly associated with JRA (OR = 0.35, p = 0.00005) and asthma (OR = 0.61, p = 0.007). We found no association between FCRL3 SNPs or haplotypes and childhood-onset SLE. These results supported the notion that FCRL3 is involved in the etiology of several immune diseases. Our results also suggested that SNPs located in the FCRL3 gene were protective against JRA and asthma in male Mexican patients.     

Polymorphisms in metalloproteinase-9 are associated with the risk for asthma in Mexican pediatric patients

Asthma is characterized by chronic airway inflammation, which induces airway remodelling of the extracellular matrix over time. Matrix metalloproteinases (MMPs) are involved in this process, and single-nucleotide polymorphisms (SNPs) in MMP genes may influence their mRNA expression levels or abilities to bind substrates and inhibitors, thereby contributing to asthma predisposition and severity. MMP-9 is highly expressed in airways and many studies support its involvement in asthma pathogenesis; however the contribution of MMP-9 SNPs is controversial. To investigate whether MMP-9 SNPs are associated with childhood-onset asthma in Mexican patients we conducted a case-control study including 403 children with clinical asthma diagnoses and 426 healthy controls from Mexico. The cases and controls were matched by ethnicity and gender. We found that the SNPs rs2274755, rs17577, and rs3918249 were associated with asthma risk. The most significant associations were with rs2274755 (OR = 2.10, 95% CI 1.31–3.39, P = 0.001) and rs17577 (OR = 2.07, 95% CI 1.29–3.30, P = 0.001); which were in strong linkage disequilibrium. Both SNPs were also associated with atopic asthma (OR = 2.38, 95% CI 1.44–3·96, P = 0.0005). The SNP rs3918249 exhibited a female gender-dependent association with asthma (OR = 1.66, 95% CI 1.14–2.43, P = 0.007). Our results suggest that MMP-9 polymorphisms could play a role in the susceptibility to childhood-onset asthma.     

The natural history of a genetic subtype of arrhythmogenic right ventricular cardiomyopathy caused by a p.S358L mutation in TMEM43

To determine the phenotype and natural history of a founder genetic subtype of autosomal dominant arrhythmogenic right ventricular cardiomyopathy (ARVC) caused by a p.S358L mutation in TMEM43. The age of onset of cardiac symptoms, clinical events and test abnormalities were studied in 412 subjects (258 affected and 154 unaffected), all of which occurred in affected males significantly earlier and more often than unaffected males. Affected males were hospitalized four times more often than affected females (p ≤ 0.0001) and died younger (p ≤ 0.001). The temporal sequence from symptoms onset to death was prolonged in affected females by 1–2 decades. The most prevalent electrocardiogram (ECG) manifestation was poor R wave progression (PRWP), with affected males twice as likely to develop PRWP as affected females (p ≤ 0.05). Left ventricular enlargement (LVE) occurred in 43% of affected subjects, with 11% fulfilling criteria for dilated cardiomyopathy. Ventricular ectopy on Holter monitor was common and occurred early: the most diagnostically useful clinical test. No symptom or test could rule out diagnosis. This ARVC subtype is a sex‐influenced lethal arrhythmogenic cardiomyopathy, with a unique ECG finding, LV dilatation, heart failure and early death, where molecular pre‐symptomatic diagnosis has the greatest clinical utility.     

Primary versus post-treatment apical periodontitis: microbial composition,lipopolysaccharides and lipoteichoic acid levels,signs and symptoms

Clinical Oral Investigations - To compare the microbial load and composition and to determine the lipopolysaccharides (LPS) and lipoteichoic acid (LTA) concentrations found in primary apical...     

MRI findings in people with epilepsy and nodding syndrome in an area endemic for onchocerciasis: an observational study

Background

Onchocerciasis has been implicated in the pathogenesis of epilepsy. The debate on a potential causal relationship between Onchocerca volvulus and epilepsy has taken a new direction in the light of the most recent epidemic of nodding syndrome.

Objective

To document MRI changes in people with different types of epilepsy and investigate whether there is an association with O. volvulus infection.

Methods

In a prospective study in southern Tanzania, an area endemic for O. volvulus with a high prevalence of epilepsy and nodding syndrome, we performed MRI on 32 people with epilepsy, 12 of which suffered from nodding syndrome. Polymerase chain reaction (PCR) of O. volvulus was performed in skin and CSF.

Results

The most frequent abnormalities seen on MRI was atrophy (twelve patients (37.5%)) followed by intraparenchymal pathologies such as changes in the hippocampus (nine patients (28.1%)), gliotic lesions (six patients (18.8%)) and subcortical signal abnormalities (three patients (9.4%)). There was an overall trend towards an association of intraparenchymal cerebral pathologies and infection with O. volvulus based on skin PCR (Fisher''s Exact Test p=0.067) which was most pronounced in children and adolescents with nodding syndrome compared to those with other types of epilepsy (Fisher''s Exact Test, p=0.083). Contrary to skin PCR results, PCR of CSF was negative in all patients.

Conclusion

The observed trend towards an association of intraparenchymal cerebral pathological results on MRI and a positive skin PCR for O. volvulus despite negative PCR of CSF is intriguing and deserves further attention.