Neonatal DNA methylation profile in human twins is specified by a complex interplay between intrauterine environmental and genetic factors, subject to tissue-specific influence

Comparison between groups of monozygotic (MZ) and dizygotic (DZ) twins enables an estimation of the relative contribution of genetic and shared and nonshared environmental factors to phenotypic variability. Using DNA methylation profiling of ～20,000 CpG sites as a phenotype, we have examined discordance levels in three neonatal tissues from 22 MZ and 12 DZ twin pairs. MZ twins exhibit a wide range of within-pair differences at birth, but show discordance levels generally lower than DZ pairs. Within-pair methylation discordance was lowest in CpG islands in all twins and increased as a function of distance from islands. Variance component decomposition analysis of DNA methylation in MZ and DZ pairs revealed a low mean heritability across all tissues, although a wide range of heritabilities was detected for specific genomic CpG sites. The largest component of variation was attributed to the combined effects of nonshared intrauterine environment and stochastic factors. Regression analysis of methylation on birth weight revealed a general association between methylation of genes involved in metabolism and biosynthesis, providing further support for epigenetic change in the previously described link between low birth weight and increasing risk for cardiovascular, metabolic, and other complex diseases. Finally, comparison of our data with that of several older twins revealed little evidence for genome-wide epigenetic drift with increasing age. This is the first study to analyze DNA methylation on a genome scale in twins at birth, further highlighting the importance of the intrauterine environment on shaping the neonatal epigenome.     

Knowledge and risk factors of intestinal parasitic infections among women in Makurdi,Benue State

ObjectiveTo assess women's perceptions and risk factors that could expose them to intestinal parasitic infections in Makurdi, Benue State, Nigeria.MethodsA total of 750 faecal samples were collected from women at different reproductive stages (pre-menstrual, menstrual and post-menstrual), and the faeces were tested by the formol ether concentration technique.ResultsA total of 426 (56.8%) samples were found positive for various intestinal parasites with hookworm (4.8%), Ascaris lumbricoides (9.3%), Taenia sp (2.1%), Entamoeba histolytica (18.9%) and Entamoeba coli (21.6%). Women at pre-menstrual and post-menstrual stages recorded higher prevalence rates with 72.8% and 63.9%, respectively. No significant difference in prevalence was observed between women at different reproductive stages and women infected by different parasites (χ² = 30.6, P > 0.05). Sweet things, rotten fruits and improperly cooked meat were perceived as the causes of intestinal parasitic infections among the pre and post menstrual women. Sources of drinking water like river, well, water bought from vendors and patronizing food vendors were observed as risk factors contributing to the prevalence of intestinal parasitic infections among women. Factors like not washing hands before eating and after defaecation, use of leaves and ordinary papers for cleaning after defaecation were also observed to be contributing to the prevalence of intestinal parasitic infections.ConclusionsPersuasive health education and rigorous hygiene measures should be employed in schools, maternity clinics and among the populace to reduce transmission and infection with intestinal parasites.     

Bullet and Blast ENT Injuries in Counter-Insurgency Area

Background

Many ENT injuries are not recognized easily, but they have the potential of increasing the morbidity.

Methods

ENT injuries managed in two tertiary care Level-IV hospitals between 2006 and 2007 were studied with a view to formulate strategy in efficient management of these cases.

Result

Emergency bags did not carry readymade packs to control nasal bleeds. Routinely screening of ears in all blast injury cases in the ‘Blast Injury Program’ helped in early identification of hearing loss. Lack of sufficient stenting of nasal cavities resulted in severe nasal stenosis which was difficult to repair. Splinters lodged in pharyngeal wall escaped detection, resulting in concealed haemorrhage and shock.

Conclusion

Nasal packs and epistaxis catheters must be included in emergency bags to minimize blood loss at first contact. Screening for ear trauma in all blast injuries increases detection rate and is beneficial to the soldier. Stenting of injured nasal cavities and early transfer to a tertiary care hospital could reduce morbidity. Plain radiography of head and neck areas could help detect splinters in vital areas and guide management.Key Words: Combat injuries ENT, Blast injuries ear     

Impact of Endoscopic Sinus Surgery on Symptom Manifestation of Chronic Rhinosinusitis

Background

Rhinosinusitis is a significant health problem which results in large financial burden on society. The study evaluated the prevalence and severity of individual symptoms of chronic rhinosinusitis (CRS) and the impact of endoscopic sinus surgery (ESS) on the symptoms and medication used in patients with CRS.

Methods

Patients with refractory CRS were assessed prospectively with ESS intervention. We studied the symptoms, change in medical therapy, complications of surgery and effect of other factors like smoking, polyposis and asthma on endoscopy and computed tomography scan scores.

Result

A total of 81 patients underwent ESS for CRS. Post nasal drip (95%), headache (91%), nasal discharge (90%) and nasal obstruction (86%) were the commonest symptoms. Postoperatively, the highest improvement was seen in nasal blockage (87.2%), postnasal drip (84.4%) and headache (82.4%). Endoscopy scores were significantly worse in patients with polyps, asthma and smoking. A significant reduction in use of antibiotic and antihistaminics was seen post surgery. Seven patients who had extensive polyposis preoperatively, had recurrence and required revision surgery. Nasal synechiae formation and mild bleeding were the minor complications.

Conclusion

Endoscopic sinus surgery results in significant improvement in the symptoms of patients with CRS alongwith a definitive decrease in antibiotic and antihistaminic requirement. We conclude that ESS is an effective treatment for CRS in those who fail to respond to medical treatment.Key Words: Chronic rhinosinusitis, Endoscopic sinus surgery     

Unconventional translation of mammalian LINE-1 retrotransposons

Long Interspersed Element-1 (LINE-1 or L1) retrotransposons encode proteins required for their mobility (ORF1p and ORF2p), yet little is known about how L1 mRNA is translated. Here, we show that ORF2 translation generally initiates from the first in-frame methionine codon of ORF2, and that both ORF1 and the inter-ORF spacer are dispensable for ORF2 translation. Remarkably, changing the ORF2 AUG codon to any other coding triplet is compatible with retrotransposition. However, introducing a premature termination codon in ORF1 or a thermostable hairpin in the inter-ORF spacer reduces ORF2p translation or L1 retrotransposition to approximately 5% of wild-type levels. Similar data obtained from "natural" and codon optimized "synthetic" mouse L1s lead us to propose that ORF2 is translated by an unconventional termination/reinitiation mechanism.