WFS1 Gene-associated Diabetes Phenotypes and Identification of a Founder Mutation in Southern India.

CONTEXT: Wolfram syndrome (WFS) is a rare autosomal recessive disorder characterized by juvenile-onset diabetes, diabetes insipidus, optic atrophy, deafness, and progressive neurodegeneration. However, due to the progressive nature of the disease and a lack of complete clinical manifestations, a confirmed diagnosis of WFS at the time of onset of diabetes is a challenge. OBJECTIVE: With WFS1 rare heterozygous variants reported in diabetes, there is a need for comprehensive genetic screening strategies for the early diagnosis of WFS and delineating the phenotypic spectrum associated with the WFS1 gene variants in young-onset diabetes. METHODS: This case series of 11 patients who were positive for WFS1 variants were identified with next-generation sequencing (NGS)-based screening of 17 genemonogenic diabetes panel. These results were further confirmed with Sanger sequencing. RESULTS: 9 out of 11 patients were homozygous for pathogenic/likely pathogenic variants in the WFS1 gene. Interestingly, 3 of these probands were positive for the novel WFS1 (NM_006005.3): c.1107_1108insA (p.Ala370Serfs*173) variant, and haplotype analysis suggested a founder effect in 3 families from Southern India. Additionally, we identified 2 patients with young-onset diabetes who were heterozygous for a likely pathogenic variant or a variant of uncertain significance in the WFS1 gene. CONCLUSION: These results project the need for NGS-based parallel multigene testing as a tool for early diagnosis of WFS and identify heterozygous WFS1 variants implicated in young-onset diabetes.

Active versus passive case finding for tuberculosis in marginalised and vulnerable populations in India: comparison of treatment outcomes.

Background: Community-based active case finding (ACF) for tuberculosis (TB) implemented among marginalised and vulnerable populations in 285 districts of India resulted in reduction of diagnosis delay and prevalence of catastrophic costs due to TB diagnosis. We were interested to know whether this translated into improved treatment outcomes. Globally, there is limited published literature from marginalised and vulnerable populations on the independent effect of community-based ACF on treatment outcomes when compared to passive case finding (PCF). Objectives: To determine the relative differences in unfavourable treatment outcomes (death, loss-to-follow-up, failure, not evaluated) of ACF and PCF-diagnosed people. Methods: Cohort study involving record reviews and interviews in 18 randomly selected districts. We enrolled all ACF-diagnosed people with new smear-positive pulmonary TB, registered under the national TB programme between March 2016 and February 2017, and an equal number of randomly selected PCF-diagnosed people in the same settings. We used log binomial models to adjust for confounders. Results: Of 572 enrolled, 275 belonged to the ACF and 297 to the PCF group. The proportion of unfavourable outcomes were 10.2% (95% CI: 7.1%, 14.3%) in the ACF and 12.5% (95% CI: 9.2%, 16.7%) in the PCF group (p = 0.468). The association between ACF and unfavourable outcomes remained non-significant after adjusting for confounders available from records [aRR: 0.83 (95% CI: 0.56, 1.21)]. Due to patient non-availability at their residence, interviews were conducted for 465 (81.3%). In the 465 cohort too, there was no association after adjusting for confounders from records and interviews [aRR: 1.05 (95% CI: 0.62, 1.77)]. Conclusion: We did not find significant differences in the treatment outcomes. Due to the wide CIs, studies with larger sample sizes are urgently required. Studies are required to understand how to translate the benefits of ACF to improved treatment outcomes.

Local relative density modulates failure and strength in vertically aligned carbon nanotubes.

Micromechanical experiments, image analysis, and theoretical modeling revealed that local failure events and compressive stresses of vertically aligned carbon nanotubes (VACNTs) were uniquely linked to relative density gradients. Edge detection analysis of systematically obtained scanning electron micrographs was used to quantify a microstructural figure-of-merit related to relative local density along VACNT heights. Sequential bottom-to-top buckling and hardening in stress-strain response were observed in samples with smaller relative density at the bottom. When density gradient was insubstantial or reversed, bottom regions always buckled last, and a flat stress plateau was obtained. These findings were consistent with predictions of a 2D material model based on a viscoplastic solid with plastic non-normality and a hardening-softening-hardening plastic flow relation. The hardening slope in compression generated by the model was directly related to the stiffness gradient along the sample height, and hence to the local relative density. These results demonstrate that a microstructural figure-of-merit, the effective relative density, can be used to quantify and predict the mechanical response.