Growth Pattern of Preterm Newborns under 34 Weeks of Gestation in a Tertiary Care Hospital, Tamil Nadu, India: A Retrospective Study

Introduction: The proportion of preterm babies is increasing now a days and these babies are more prone to short and long term disabilities. Hence, growth monitoring is essential, to identify the premature infants, who are at increased risk of growth lag and poor neurodevelopmental outcomes. Aim: To assess the growth pattern of infants, who are born ≤34 weeks of gestational age using the intergrowth-21st growth charts. Materials and Methods: This retrospective study was conducted in the Department of Neonatology at Chengalpattu Medical College and Hospital, a Tertiary Care Center Chengalpattu, Tamil Nadu, India. The duration of the study was one year, from January 2020 to December 2020. A total of 118 neonates born at ≤34 weeks gestational age, who were admitted in the hospital and stayed for 14 days and more were included in the study. The data was collected from discharge sheets and an electronic database. Intergrowth-21st growth charts are used to assess growth. Weight, duration of hospital stay and Extrauterine Growth Restriction (EUGR) were assessed for all the newborns. At discharge, the EUGR status of the babies was determined using a weight ≤-1.28 Standard Deviation (SD) criterion. Continuous variables were presented as means with SD. The data was analysed using Statistical Package for Social Sciences (SPSS) version 24.0. Results: The mean maternal and gestational age of the study participants was 24.9±4.14 years and 31.6 ±1.42 weeks and birth weight of babies were 1608.06 gm (±275), respectively. The proportions of Appropriate for gestational age (AGA) and Small For Gestational Age (SGA) were 95 (80.5%) and 18 (15.2%), respectively. The mean time to reach full feeds was 10.4 days (±2.7days), and the duration of stay in the hospital was 24.8 days (±9.6 days). The mean discharge weight and gestational age of babies were 1732 gm (±226 gm) and 35.4 weeks (±1.47 weeks), respectively. The common complications observed, were those requiring antibiotics (73.7%), respiratory support (61.01%), and Respiratory Distress Syndrome (RDS) (22.8%). Conclusion: Preterm newborns are more vulnerable to EUGR. The EUGR proportion in present study was 72.8%. The issues that raise the risk of EUGR, during the hospital stay must be adequately addressed in order to ensure that, preterm neonates develops normally

Understanding variable disease severity in X-linked retinoschisis: Does RS1 secretory mechanism determine disease severity?

<div><p>X-linked retinoschisis (XLRS) is a retinal degenerative disorder caused by mutations in <i>RS1</i> gene leading to splitting of retinal layers (schisis) which impairs visual signal processing. Retinoschisin (RS1) is an adhesive protein which is secreted predominantly by the photoreceptors and bipolar cells as a double-octameric complex. In general, XLRS patients show wide clinical heterogeneity, presenting practical challenges in disease management. Though researchers have attempted various approaches to offer an explanation for clinical heterogeneity, the molecular basis has not been understood yet. Therefore, this study aims at establishing a link between the phenotype and genotype based on the molecular mechanism exerted by the mutations. Twenty seven XLRS patients were enrolled, of which seven harboured novel mutations. The mutant constructs were genetically engineered and their secretion profiles were studied by <i>in vitro</i> cell culture experiments. Based on the secretory profile, the patients were categorized as either secreted or non-secreted group. Various clinical parameters such as visual acuity, location of schisis, foveal thickness and ERG parameters were compared between the two groups and control. Although the two groups showed severe disease phenotype in comparison with control, there was no significant difference between the two XLRS groups. However, the secreted group exhibited relatively severe disease indications. On the other hand molecular analysis suggests that most of the <i>RS1</i> mutations result in intracellular retention of retinoschisin. Hence, clinical parameters of patients with non-secreted profile were analyzed which in turn revealed wide variability even within the group. Altogether, our results indicate that disease severity is not merely dependent on secretory profile of the mutations. Thus, we hypothesize that intricate molecular detail such as the precise localization of mutant protein in the cell as well as its ability to assemble into a functionally active oligomer might largely influence disease severity among XLRS patients.</p></div

Hydrophobic and hydrophilic effects of multimeric <i>RS1</i> mutant structures inferred by <i>in silico</i> analysis.

<p>Hydrophobic and hydrophilic effects of multimeric <i>RS1</i> mutant structures inferred by <i>in silico</i> analysis.</p

Clinical data of XLRS patients showing non-secreted RS1 profile.

<p>Clinical data of XLRS patients showing non-secreted RS1 profile.</p

Comparison of ERG parameters between control samples and XLRS patients showing non-secreted or secreted or protein profile.

<p>Comparison of ERG parameters between control samples and XLRS patients showing non-secreted or secreted or protein profile.</p

Comparison of ocular features between non-secreted and secreted XLRS groups.

<p>Comparison of ocular features between non-secreted and secreted XLRS groups.</p

Immunoblot analysis of WT and RS1 mutants in cellular and secreted fractions of COS7 cells.

<p>RS1 was detected using anti-FLAG antibody after 72 hours of transfection. Un-transfected lane served as negative control.</p

List of XLRS patients and their clinical characteristics.

<p>List of XLRS patients and their clinical characteristics.</p