Mefenamic acid-induced bilateral transient myopia, secondary angle closure glaucoma and choroidal detachment

Drug-induced secondary angle closure is quite common and in the majority of cases simply stopping the medication leads to rapid reversal of the condition and resolution of glaucoma. We describe here a patient who presented with secondary angle closure glaucoma and myopia following mefenamic acid ingestion which was managed successfully by stopping the medication, symptomatic treatment and reassurance.     

Improvement in intraoperative transcranial electrical motor-evoked potentials in tethered cord surgery: an analysis of 45 cases

Background

Improvement of transcranial electrical motor-evoked potentials (TeMEPs) following untethering during tethered cord surgery (TCS) and its clinical significance have not been analyzed in the literature.

Methods

Forty-five consecutive cases of tethered cord were operated on with multimodality intraoperative neurophysiological monitoring (IONM) between February 2005 and January 2012. Intraoperative TeMEP change was classified as improvement, worsening or no change. Motor, sensory, bladder and bowel symptoms and signs were evaluated preoperatively, in the first week post-surgery and at the last follow-up (maximum of 2 years).

Results

Patient age ranged from 5 to 44 years (mean, 16?±?10 years), with 30 children. Intraoperative MEPs improved in 23 (51 %), remained the same in 21 (46.7 %) and worsened in 1 (2 %) patient. Motor improvement occurred in 7 patients and clinical improvement in 17 patients in the immediate postoperative period. Postoperative neurological worsening occurred in one patient (2.2 %). Improved and stable MEPs correlated with the motor (p?=?0.002) and clinical improvement (p?=?0.02) in the immediate postoperative period. Follow-up was available in 35 patients (77.7 %), ranging from 5 to 24 months (median, 21 months; mean, 17.7?±?6.8 months). There was late clinical improvement in 73.5 % of the patients in whom the intraoperative MEP had remained the same or improved. However, there was no statistically significant correlation between MEP change and long-term outcome.

Conclusions

Intraoperative MEP improvement occurs in about 50 % of the patients following successful untethering. This finding probably provides support to the ischemic theory of tethered cord syndrome.     

Posttranslational modification of CENP-A influences the conformation of centromeric chromatin

Centromeres are chromosomal loci required for accurate segregation of sister chromatids during mitosis. The location of the centromere on the chromosome is not dependent on DNA sequence, but rather it is epigenetically specified by the histone H3 variant centromere protein A (CENP-A). The N-terminal tail of CENP-A is highly divergent from other H3 variants. Canonical histone N termini are hotspots of conserved posttranslational modification; however, no broadly conserved modifications of the vertebrate CENP-A tail have been previously observed. Here, we report three posttranslational modifications on human CENP-A N termini using high-resolution MS: trimethylation of Gly1 and phosphorylation of Ser16 and Ser18. Our results demonstrate that CENP-A is subjected to constitutive initiating methionine removal, similar to other H3 variants. The nascent N-terminal residue Gly1 becomes trimethylated on the α-amino group. We demonstrate that the N-terminal RCC1 methyltransferase is capable of modifying the CENP-A N terminus. Methylation occurs in the prenucleosomal form and marks the majority of CENP-A nucleosomes. Serine 16 and 18 become phosphorylated in prenucleosomal CENP-A and are phosphorylated on asynchronous and mitotic nucleosomal CENP-A and are important for chromosome segregation during mitosis. The double phosphorylation motif forms a salt-bridged secondary structure and causes CENP-A N-terminal tails to form intramolecular associations. Analytical ultracentrifugation of phospho-mimetic CENP-A nucleosome arrays demonstrates that phosphorylation results in greater intranucleosome associations and counteracts the hyperoligomerized state exhibited by unmodified CENP-A nucleosome arrays. Our studies have revealed that the major modifications on the N-terminal tail of CENP-A alter the physical properties of the chromatin fiber at the centromere.     

Influence of single nucleotide polymorphisms in H-Ras and cyclin D1 genes on oral cancer susceptibility

Although tobacco usage and alcohol consumption are the major risk factors for oral cancer, there are individual variations in genetic susceptibility to oral cancer. The Ras pathway plays an important role in oral carcinogenesis. High percentage of Ras mutation in oral carcinoma was reported from India. Cyclin D1, a downstream member of the Ras pathway, was also shown to be overexpressed in the majority of oral cancers and the overexpression was shown to be associated with poor prognosis. In the present study, we have evaluated the association of the single nucleotide polymorphisms in the H-Ras (C81T) and cyclin D1 (A870G and C1722G) genes and oral cancer risk in 176 oral cancer cases and 142 hospital based controls matched by age and sex. All the polymorphisms studied conformed to Hardy-Weinberg equilibrium. The comparison of the CCND1 A870G and C1722G genotype frequencies in cases and controls did not show any significant association with oral cancer risk. In H-Ras C81T polymorphism, TC+CC genotype showed a one and half fold increased risk (OR=1.59) for oral cancer. On stratified analysis, the observed increased risk was more evident among men (OR=2), while such an increased risk was not seen among women. Thus, our data suggests that the variant 'C' allele of the H-Ras (C81T) is associated with a higher risk for oral carcinoma, particularly in male population and thus, this polymorphism could be a low penetrance gene predisposition factor for oral carcinoma.     

Subtenons infection by Dirofilaria repens

Zoonotic filariasis caused by Dirofilaria repens, a parasite of carnivores occurs mainly in countries surrounding Mediterranean region. The infection occurs in and around eye among animal handlers through vector transmission. We are reporting a case of human Dirofilariasis affecting subtenons region in a 63 year-old woman from Coimbatore, South India. The purpose of this article is to review the clinical course and management of ocular Dirofilariasis.     

Euprolactinemic gynecomastia and galactorrhea with risperidone-fluvoxamine combination

Risperidone is associated with hyperprolactinemia and its consequent symptoms such as gynecomastia, galactorrhea and sexual dysfunction in adults, and less so in adolescents. Rarely, serotonin reuptake inhibitors are also associated with such adverse effects. We report a case of gynecomastia and galactorrhea in an adolescent male while on a combination of risperidone and fluvoxamine, although the serum prolactin was within normal range.