Seizures Due to Insulinoma- A Rare but Treatable Cause.

Hypoglycemia can cause multiple neuroglycopenic symptoms; seizures being one of them. Misdiagnosis and delay in treatment are common and prolonged hypoglycemia can lead to permanent neurological deficit or fatal coma. Hypoglycemia caused by an insulinoma is a readily treatable condition that should be considered in the differential diagnosis of intractable seizures. The following case report highlights the need for careful reassessment of all seizures that are atypical and refractory to medication.

Effect of the myotonic dystrophy (DM) mutation on mRNA levels of the DM gene.

Myotonic dystrophy (DM) results from the amplification of an unstable CTG repeat in the 3' untranslated region of a transcript encoding a putative serine/threonine kinase. We have analysed the amplification of the repeat and the steady state levels of the DM kinase (DMK) mRNA in tissues and cell lines from normal and congenital DM individuals. Southern blot analysis of DNA samples from a severely affected neonate shows somatic heterogeneity of the repeat in all tissues studied. RNA analyses on these tissues show a marked increase in DMK steady state mRNA levels. We demonstrate that the mutant DMK allele is expressed regardless of the number of CTG repeats and that the increase in DMK mRNA levels is due to elevated mutant mRNA levels. We postulate that elevated DMK levels explains the dominant inheritance pattern of DM.

Multiple intracranial tubercular abscesses in a child.

2 Year old girl presented with fever and cough for 4 months. Neurological examination revealed right sided hemiplegia. Contrast enhanced computed tomography of brain showed multiple hypodense ring enhancing lesions. Pus on aspiration of intracranial abscess showed positive polymerase chain reaction for Mycobacterium tuberculosis. A possibility of tuberculosis though not commonly recognised may be considered in any child presenting with prolonged fever and multiple intracranial abscesses.

Myotonic dystrophy mutation: an unstable CTG repeat in the 3' untranslated region of the gene.

Myotonic dystrophy (DM) is the most common inherited neuromuscular disease in adults, with a global incidence of 1 in 8000 individuals. DM is an autosomal dominant, multisystemic disorder characterized primarily by myotonia and progressive muscle weakness. Genomic and complementary DNA probes that map to a 10-kilobase Eco RI genomic fragment from human chromosome 19q13.3 have been used to detect a variable length polymorphism in individuals with DM. Increases in the size of the allele in patients with DM are now shown to be due to an increased number of trinucleotide CTG repeats in the 3' untranslated region of a DM candidate gene. An increase in the severity of the disease in successive generations (genetic anticipation) is accompanied by an increase in the number of trinucleotide repeats. Nearly all cases of DM (98 percent or 253 of 258 individuals) displayed expansion of the CTG repeat region. These results suggest that DM is primarily caused by mutations that generate an amplification of a specific CTG repeat.

Chikungunya outbreak in Delhi, India, 2016: report on coinfection status and comorbid conditions in patients.

Chikungunya fever is a major public health issue in India affecting billions. After 2010, the infection was in a decline until in 2016, when a massive outbreak affected the country. In this report, we present serologic and molecular investigations of 600 patient samples for chikungunya and dengue viruses along with clinical and comorbidity features. We recruited 600 patients during this outbreak and evaluated them for chikungunya and dengue virus antibodies and virus RNA through IgM, NS1 antigen and quantitative real-time PCR (qPCR). We further evaluated Zika virus RNA by qPCR. Additionally, we documented all clinical and comorbid features that were observed during the outbreak in the hospital. We report a total incidence rate of 58% of chikungunya during the outbreak in our hospital. Within the recruited patients, 70% of the patients were positive for chikungunya virus IgM whereas 24.17% were positive by qPCR. None of the samples was positive for Zika virus RNA. Additionally, coinfection of dengue and chikungunya was seen in 25.33% of patients. Analysis of clinical features revealed that 97% of patients had restricted movements of the joints with other features like swelling, itching and rashes of varying severity observed. Twelve patients presented with comorbid conditions, and two fatalities occurred among these comorbid patients. The high incidence of coinfection in the current outbreak warrants implementation of routine testing of both chikungunya and dengue virus in suspected patients for better patient management. The post-acute phase complications reported in the hospitals require in-depth studies to understand the actual impact of the current outbreak.

Myotonic dystrophy (DM) protein kinase levels in congenital and adult DM patients.

Myotonic dystrophy is caused by a (CTG)n trinucleotide repeat expansion located in the 3' untranslated region of the myotonic dystrophy protein kinase gene (DMPK). To date, the disease mechanism has proven elusive. The mutation would not be expected to affect kinase function and yet the disease is inherited in a dominant fashion. Mutant DMPK transcripts have been demonstrated to be retained in affected cell nuclei which could reduce DMPK protein levels and cause disease by haploinsufficiency. An alternate hypothesis is that the expansion confers a toxic gain of function on the transcript. In previous studies, various 52-55 kDa proteins have been detected using antisera targeted against DMPK and a decline of two of these candidates in disease tissues was reported. Current information now suggests that these proteins are not products of the myotonic dystrophy gene. We have characterised an antiserum which has been confirmed to recognise authentic 71 and 80 kDa isoforms of DMPK. Determination of the kinase levels in disease tissues with controls for patient age and tissue integrity demonstrates a modest overexpression in adult patients. In tissues from severely affected congenital patients only a slight decline is seen. This data argues against DMPK haploinsufficiency as a disease mechanism.

Tigecycline.

Infection with resistant pathogens can adversely affect clinical, microbiological and economic outcomes. New agents for the treatment of many such serious infections are acutely needed in hospital practice. Tigecycline is a novel glycylcycline antimicrobial for intravenous use. It has an expanded broad-spectrum antibacterial activity including multi-drug resistant pathogens, like methicillin-resistant Staphylococcus aureus , vancomycin-resistant enterococci , multi-drug resistant Streptococcus pneumoniae , extended-spectrum beta-lactamase-producing gram-negative bacteria and Acinetobacter baumannii . Tigecycline however is not active against Proteus, Providencia and Pseudomonas species. Its currently approved indications include complicated skin and skin structure infections and complicated intra-abdominal infections. It has also been found to be effective for the treatment of community- as well as hospital-acquired and ventilator-associated pneumonia and bacteremia, sepsis with shock and urinary tract infections. Tigecycline appears to be a valuable treatment option for the management of superbugs, especially where conventional therapy has failed.

XIAP-mediated neuroprotection in retinal ischemia.

Retinal ischemia results in the loss of vision in a number of ocular diseases including acute glaucoma, diabetic retinopathy, hypertensive retinopathy and retinal vascular occlusion. Recent studies have shown that most of the neuronal death that leads to loss of vision results from apoptosis. XIAP-mediated gene therapy has been shown to protect a number of neuronal types from apoptosis but has never been assessed in retinal neurons following ischemic-induced cell death. We injected an adeno-associated viral vector expressing XIAP or GFP into rat eyes and 6 weeks later, rendered them ischemic by raising intraocular pressure. Functional analysis revealed that XIAP-treated eyes retained larger b-wave amplitudes than GFP-treated eyes up to 4 weeks post-ischemia. The number of cells in the inner nuclear layer (INL) and the thickness of the inner retina were significantly preserved in XIAP-treated eyes compared to GFP-treated eyes. Similarly, there was no significant reduction in optic nerve axon numbers in XIAP-treated eyes. There were also significantly fewer TUNEL (TdT-dUTP terminal nick end labeling) positive cells in the INL of XIAP-treated retinas at 24 h post-ischemia. Thus, XIAP-mediated gene therapy imparts both functional and structural protection to the retina after a transient ischemic episode.

Overexpression of 3'-untranslated region of the myotonic dystrophy kinase cDNA inhibits myoblast differentiation in vitro.

The genetic defect underlying myotonic dystrophy (DM) has been identified as an unstable CTG trinucleotide repeat amplification in the 3'-untranslated region (3'-UTR) of the DM kinase gene (DMK). Individuals with the most severe congenital form display a marked delay in muscle terminal differentiation. To gain insight into the role of DMK during myogenesis, we have examined the effect of DMK overexpression on the terminal differentiation of the murine myoblast cell line C2C12. We demonstrate that a 4-10-fold constitutive overexpression of DMK mRNA in myoblasts caused a marked inhibition of terminal differentiation. Surprisingly, this activity was mapped to a 239-nucleotide region of the 3'-UTR of the DMK transcript. When the DMK 3'-UTR was placed downstream of a reporter gene, the same inhibition of myogenesis was observed. Following the induction of differentiation of myoblast clones overexpressing the DMK 3'-UTR, the levels of myogenin mRNA were reduced by approximately 4-fold, whereas the steady state levels of mef-2c transcripts were not affected. These data suggest that overexpression of the DMK 3'-UTR may interfere with the expression of musclespecific mRNAs leading to a delay in terminal differentiation.

Isolation of a novel G protein-coupled receptor (GPR4) localized to chromosome 19q13.3.

We present the cloning and sequencing of the human gene for a novel G-protein coupled receptor (GPR4), from the critical myotonic dystrophy (DM) region on chromosome 19q13.3. The homologous porcine gene was isolated and sequenced as well. The genes of both species are intronless and contain an open reading frame encoding a protein of 362 amino acids. In human, two isoforms of GPR4 are expressed, differing in their 3' untranslated region due to the use of alternate polyadenylation signals and measuring approximately 2.8 and 1.8 kb, respectively. Northern blot analysis showed that GPR4 is widely expressed, with higher levels in kidney, heart, and especially lung, where it is at least fivefold greater than in other tissues. Sequence analysis suggests that GPR4 is a peptide receptor and shares strongest homologies with purinergic receptors and receptors for angiotensin II, platelet activating factor, thrombin, and bradykinin.

Isolation and characterization of human patched 2 (PTCH2), a putative tumour suppressor gene inbasal cell carcinoma and medulloblastoma on chromosome 1p32.

Mutations of the human Patched gene ( PTCH ) have been identified in individuals with the nevoid basal cell carcinoma syndrome (NBCCS) as well as in sporadic basal cell carcinomas and medulloblastomas. We have isolated a homologue of this tumour suppressor gene and localized it to the short arm of chromosome 1 (1p32.1-32.3). Patched 2 ( PTCH2 ) comprises 22 coding exons and spans approximately 15 kb of genomic DNA. The gene encodes a 1203 amino acid putative transmembrane protein which is highly homologous to the PTCH product. We have characterized the genomic structure of PTCH2 and have used single-stranded conformational polymorphism analysis to search for mutations in PTCH2 in NBCCS patients, basal cell carcinomas and in medulloblastomas. To date, we have identified one truncating mutation in a medulloblastoma and a change in a splice donor site in a basal cell carcinoma, suggesting that the gene plays a role in the development of some tumours.