Madhulika Kabra

Poly (propyleneimine) dendrimer based nanocontainers for targeting of efavirenz to human monocytes/macrophages in vitro.

Cells of the mononuclear phagocytic system, in particular monocytes/macrophages (Mo/Mac) serve as a reservoir for human immunodeficiency virus (HIV) and are believed to be responsible for its dissemination throughout the body and especially into the brain. Treatment of HIV infection, therefore, must reach these cells in addition to the lymphocytes. The purpose of the present study is to develop poly(propyleneimine) (PPI) dendrimer-based nanocontainers for targeting of efavirenz (EFV) to Mo/Mac. Fifth generation PPI dendrimer, t-Boc–glycine conjugated PPI dendrimer (TPPI) and mannose conjugated dendrimers were synthesized and characterized. While the haemolytic activity and cytotoxicity of PPI dendrimer was found to be very high, the toxicity of t-Boc–glycine conjugated dendrimer and mannose conjugated dendrimers were found to be negligible. The entrapment efficiency of mannose conjugated dendrimer was found to be 47.4%, followed by that of PPI dendrimer (32.15%) and t-Boc–glycine conjugated dendrimer (23.1%). The in vitro drug release profile shows that while PPI dendrimer releases the drug by 24 h, the dendrimer-based nanocontainers prolong the release rate up to 144 h (83 ± 0.4% in case of t-Boc–glycine conjugated dendrimer and 91 ± 0.3% in mannose conjugated dendrimer). The cellular uptake of EFV was found to be both concentration and time dependent. Significant increase in cellular uptake of EFV by Mo/Mac cells were observed in case of mannose conjugated dendrimer which is 12 times higher than that of free drug and 5.5 times higher than that of t-Boc–glycine conjugated dendrimer. While mannose conjugated dendrimer was taken up by the lectin receptors of the cells, phagocytosis of t-Boc–glycine conjugated dendrimer might be responsible for its enhanced uptake. Results suggest that the proposed carriers hold potential to increase the efficacy and reduce the toxicity of antiretroviral therapy.

Idiopathic chronic pancreatitis in India: phenotypic characterisation and strong genetic susceptibility due to SPINK1 and CFTR gene mutations.

Objective To study the genetic predisposition, phenotype and prognosis of idiopathic chronic pancreatitis (CP). Design Prospective observational and case–control study. Setting Tertiary care academic centre. Patients Consecutive patients with CP. Interventions Detailed mutational analysis was done for the cationic trypsinogen, SPINK1 and CFTR genes with single-strand conformational polymorphism or restricted fragment length polymorphism, and sequencing. Clinical and disease characteristics of idiopathic versus alcoholic CP, and early onset versus late onset idiopathic CP were compared. Response to multimodality treatment (medical, endoscopic and/or surgical) and prognosis were analysed. Main outcome measures Genetic mutations, phenotypic characterisation and prognosis of idiopathic CP. Results Of the 411 patients with CP, 242 had idiopathic aetiology (age 27.50±11.85 years; 154 men). Malnutrition and cassava were not risk factors. SPINK1 N34S mutation was present in 42% of patients with idiopathic CP (vs 4% controls, p<0.001) and 17% of patients with alcoholic CP (p=0.016 compared with controls). In the CFTR gene, nine patients with idiopathic CP had mutations and 41 patients had polymorphisms (50% vs 10% controls, p<0.001). Diabetes developed in 35.53% of patients with idiopathic CP. About 85% of patients had significant pain relief with therapy. The probability of surviving for 35 years after onset of idiopathic CP was 83%. The typical features of tropical calcific pancreatitis were seen only in 5.8% of patients. Conclusion Strong genetic susceptibility due to SPINK1 and CFTR gene mutations, and comparative phenotype of idiopathic CP in India suggest that the term ‘tropical calcific pancreatitis’ is a misnomer.

Prevalence of the triple X syndrome in phenotypically normal women with premature ovarian failure and its association with autoimmune thyroid disorders.

OBJECTIVE To determine the prevalence of triple X females among patients with premature ovarian failure and to describe the clinical features of the syndrome. DESIGN Case report. SETTING Tertiary care hospital. PATIENT(S) Fifty-two consecutive patients with secondary amenorrhea due to premature ovarian failure and no clinical stigmata of Turners syndrome. MAIN OUTCOME MEASURE(S) Triple X syndrome and clinical features, as assessed by karyotype analysis using Giemsa trypsin banding of metaphase chromosomes. RESULT(S) Two of the 52 patients with premature ovarian failure had triple X syndrome. Both cases had associated autoimmune thyroid disorder. One of the women with triple X syndrome had two pregnancies that were complicated by premature birth, idiopathic thrombocytopenia, neonatal death, and occipital encephalocoele. CONCLUSION(S) Among patients with premature ovarian failure, 3.8% have triple X syndrome. The syndrome may be associated with autoimmune thyroid disorder and poor pregnancy outcome due to congenital malformation.

Mutations in TRIOBP, Which Encodes a Putative Cytoskeletal-Organizing Protein, Are Associated with Nonsyndromic Recessive Deafness

In seven families, six different mutant alleles of TRIOBP on chromosome 22q13 cosegregate with autosomal recessive nonsyndromic deafness. These alleles include four nonsense (Q297X, R788X, R1068X, and R1117X) and two frameshift (D1069fsX1082 and R1078fsX1083) mutations, all located in exon 6 of TRIOBP. There are several alternative splice isoforms of this gene, the longest of which, TRIOBP-6, comprises 23 exons. The linkage interval for the deafness segregating in these families includes DFNB28. Genetic heterogeneity at this locus is suggested by three additional families that show significant evidence of linkage of deafness to markers on chromosome 22q13 but that apparently have no mutations in the TRIOBP gene.

Screening of families with autosomal recessive non-syndromic hearing impairment (ARNSHI) for mutations in GJB2 gene: Indian scenario

Several studies have reported that mutations in the GJB2 gene (coding for connexin26) are a common cause of recessive non‐syndromic hearing impairment. A GJB2 mutant allele, 35delG, has been found to have a high prevalence in most ethnic groups. Though mutations in the GJB2 gene have been shown to cause autosomal recessive deafness in Indian families, the frequencies of the various mutations are still unknown. In the present study, we analyzed 45 Indian families belonging to three different states, namely, Karnataka, Tamil Nadu, and Delhi with non‐syndromic hearing impairment and an apparently autosomal recessive mode of inheritance. All the families were initially screened for three mutations (W24X, W77X, and Q124X) by using allele‐specific PCR primers; mutations were confirmed by DNA sequencing. Families that were heterozygous or negative for tested mutations of the GJB2 gene were sequenced directly to identify the complementary mutation and other mutations in GJB2. Four families were homozygous for W24X, constituting around 8.8%. In two families, the affected individuals were compound heterozygotes for W24X; one family (DKB16) carried 35delG with W24X while the other family (DKB7) carried R143W with W24X. We suggest that W24X is a common allele among the mutations screened, causing autosomal recessive non‐syndromic hearing impairment (ARNSHI) in the Indian population.

Intranasal versus intravenous lorazepam for control of acute seizures in children: A randomized open-label study

Purpose:  Intravenous lorazepam is considered the drug of first choice for control of acute convulsive seizures. However, resource or personnel constraints necessitate the study of alternative routes and medications. This study compared the efficacy and adverse effects of intranasal versus intravenous lorazepam in children aged 6–14 years who presented with acute seizures.

Further characterization of ATP6V0A2-related autosomal recessive cutis laxa.

Autosomal recessive cutis laxa (ARCL) syndromes are phenotypically overlapping, but genetically heterogeneous disorders. Mutations in the ATP6V0A2 gene were found to underlie both, autosomal recessive cutis laxa type 2 (ARCL2), Debré type, and wrinkly skin syndrome (WSS). The ATP6V0A2 gene encodes the a2 subunit of the V-type H+-ATPase, playing a role in proton translocation, and possibly also in membrane fusion. Here, we describe a highly variable phenotype in 13 patients with ARCL2, including the oldest affected individual described so far, who showed strikingly progressive dysmorphic features and heterotopic calcifications. In these individuals we identified 17 ATP6V0A2 mutations, 14 of which are novel. Furthermore, we demonstrate a localization of ATP6V0A2 at the Golgi-apparatus and a loss of the mutated ATP6V0A2 protein in patients’ dermal fibroblasts. Investigation of brefeldin A-induced Golgi collapse in dermal fibroblasts as well as in HeLa cells deficient for ATP6V0A2 revealed a delay, which was absent in cells deficient for the ARCL-associated proteins GORAB or PYCR1. Furthermore, fibroblasts from patients with ATP6V0A2 mutations displayed elevated TGF-β signalling and increased TGF-β1 levels in the supernatant. Our current findings expand the genetic and phenotypic spectrum and suggest that, besides the known glycosylation defect, alterations in trafficking and signalling processes are potential key events in the pathogenesis of ATP6V0A2-related ARCL.

Association of spink1 Gene Mutation and cftr Gene Polymorphisms in Patients With Pancreas Divisum Presenting With Idiopathic Pancreatitis

Background Pancreas divisum has been associated with idiopathic pancreatitis. However, the causal association remains controversial. Objective To study the gene mutations in patients with pancreas divisum presenting with idiopathic pancreatitis. Methods All consecutive patients with pancreas divisum presenting with recurrent pancreatitis were included in the study. Fifty healthy volunteers, 30 patients with chronic pancreatitis, and 14 patients with idiopathic recurrent acute pancreatitis without pancreas divisum served as controls. Patients and controls were tested for cationic trypsiongen gene, CFTR gene and SPINK1 gene mutations. Results Of the 12 patients with pancreas divisum and idiopathic pancreatitis, 4 had SPINK1 N34S gene mutation—3 were heterozygous and 1 was homozygous, and 1 had P55S mutation compared with 1 of 50 healthy controls with N34S mutation (P=0.001). The frequency of SPINK1 mutation was similar among patients with pancreas divisum and pancreatitis (41.6%), chronic pancreatitis (43.3%), and recurrent acute pancreatitis without pancreas divisum (35.7%). Five patients with pancreas divisum had polymorphisms in the CFTR gene. Conclusion Patients with pancreas divisum presenting with idiopathic pancreatitis had a higher frequency of SPINK1 gene mutation compared with healthy controls, which might be responsible as the sole-factor or a co-factor in causing pancreatitis in them.

Epilepsy in children with Down syndrome

This review discusses the various aspects of epilepsy in Down syndrome (DS) from the perspective of paediatric neurology. DS is the most common genetic cause of mental retardation (MR) with a reported prevalence of epilepsy of 1–13%. Infantile spasms (IS) or West syndrome (WS) is the most frequent epilepsy syndrome in children with DS. IS occur in 0.6–13% of children with DS, representing 4.5–47% of seizures in these children. Curiously, these patients have electroencephalographic (EEG) characteristics of idiopathic rather than symptomatic WS. Despite a lack of consensus on therapeutic approach, no significant difference has been reported among the different regimens with regards to achieving clinical remission or EEG normalisation. It appears that DS patients have better seizure control compared to other patients with symptomatic IS, and early initiation of appropriate treatment may contribute to the prevention of late seizure development and better developmental outcome. Lennox-Gastaut syndrome (LGS) also exhibits some distinctive features in children with DS including later onset and high incidence of reflex seizures. Other seizure types including partial and generalised tonic clonic seizures have also been described in children with DS. There is a high rate of EEG abnormalities in children with DS, even among children without epilepsy, however, no patterns specific to DS have been identified and EEG does not correlate with outcome. Various cellular and molecular mechanisms contribute to epileptogenesis in DS and offer an interesting field of study.

Velaglucerase alfa enzyme replacement therapy compared with imiglucerase in patients with Gaucher disease

Enzyme replacement therapy for Gaucher disease (GD) has been available since 1991. This study compared the efficacy and safety of velaglucerase alfa with imiglucerase, the previous standard of care. A 9‐month, global, randomized, double‐blind, non‐inferiority study compared velaglucerase alfa with imiglucerase (60 U/kg every other week) in treatment‐naïve patients aged 3–73 years with anemia and either thrombocytopenia or organomegaly. The primary endpoint was the difference between groups in mean change from baseline to 9 months in hemoglobin concentration. 35 patients were randomized: 34 received study drug (intent‐to‐treat: 17 per arm), 20 were splenectomized. Baseline characteristics were similar in the two groups. The per‐protocol population included 15 patients per arm. The mean treatment difference for hemoglobin concentration from baseline to 9 months (velaglucerase alfa minus imiglucerase) was 0.14 and 0.16 g/dL in the intent‐to‐treat and per‐protocol populations, respectively. The lower bound of the 97.5% one‐sided confidence interval in both populations lay within the pre‐defined non‐inferiority margin of −1.0 g/dL, confirming that velaglucerase alfa is non‐inferior to imiglucerase. There were no statistically significant differences in the secondary endpoints. Most adverse events were mild to moderate. No patient receiving velaglucerase alfa developed antibodies to either drug, whereas four patients (23.5%) receiving imiglucerase developed IgG antibodies to imiglucerase, which were cross‐reactive with velaglucerase alfa in one patient. This study demonstrates the efficacy and safety of velaglucerase alfa compared with imiglucerase in adult and pediatric patients with GD clinically characterized as Type 1. Differences in immunogenicity were also observed. Am. J. Hematol. 88:179–184, 2013.