Correlation of Serum Lactate Levels, Perfusion Index and Plethysmography Variability Index With Invasive Blood Pressure in Late Preterm and Term Infants With Shock.

OBJECTIVE: To study the correlation of objective parameters for diagnosing shock viz., perfusion index (PI), plethysmography variability index (PVI) and serum lactate (SL) with invasive blood pressure in late preterm and term infants with shock. METHODS: Prospective observational study (diagnostic test) conducted at the neonatal intensive care unit of Kanchi Kamakoti CHILDS Trust Hospital, Chennai between June, 2018 and May, 2020. Term and late preterm neonates with shock were included in the study. PI, PVI, SL, SpO2 and heart rate were monitored. PI, PVI and SLL were recorded at 0,12, 24 and 72 hours of onset of shock. All the babies were followed up till discharge or death. RESULTS: Total 78 neonates were enrolled in the study. At 0 hour, SL and PVI had negative correlation (P =0.002 and P=0.003) while PI had a weak-to-moderate positive correlation (P=0.002) with invasive blood pressure. SL ≥4.65 had a sensitivity of 75% and specificity of 75.8%, and PI <0.455 had a sensitivity of 65%, and specificity of 58.6% for predicting invasive hypotension. PVI ≥23.5 had a sensitivity of 90% and specificity of 63.8% in predicting invasive hypotension. CONCLUSION: PI has moderate positive correlation while SL and PVI have moderate negative correlation with invasive blood pressure. The cutoff values of SL ≥4.65, PI <0.45 and PVI ≥23.5 can predict invasive hypotension with good sensitivity and negative predictive value.

Ancient DNA Reveals Late Pleistocene Existence of Ostriches in Indian Sub-Continent.

Ancient DNA (aDNA) analysis of extinct ratite species is of considerable interest as it provides important insights into their origin, evolution, paleogeographical distribution and vicariant speciation in congruence with continental drift theory. In this study, DNA hotspots were detected in fossilized eggshell fragments of ratites (dated ≥25000 years B.P. by radiocarbon dating) using confocal laser scanning microscopy (CLSM). DNA was isolated from five eggshell fragments and a 43 base pair (bp) sequence of a 16S rRNA mitochondrial-conserved region was successfully amplified and sequenced from one of the samples. Phylogenetic analysis of the DNA sequence revealed a 92% identity of the fossil eggshells to Struthio camelus and their position basal to other palaeognaths, consistent with the vicariant speciation model. Our study provides the first molecular evidence for the presence of ostriches in India, complementing the continental drift theory of biogeographical movement of ostriches in India, and opening up a new window into the evolutionary history of ratites.

Microstructure, crystallography and diagenetic alteration in fossil ostrich eggshells from Upper Palaeolithic sites of Indian peninsular region.

Biominerals studies are of importance as they provide an understanding of natural evolutionary processes. In this study we have investigated the fossil ostrich eggshells using Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD) and Electron Backscatter Diffraction (EBSD). SEM studies demonstrated the ultrastructure of fossil eggshells and formation of calcified cuticular layer. The presence of calcified cuticle layer in eggshell is the basis for ancient DNA studies as it contains preserved biomolecules. EBSD accentuates the crystallographic structure of the ostrich eggshells with sub-micrometer resolution. It is a non-destructive tool for evaluating the extent of diagenesis in a biomineral. EBSD analysis revealed the presence of dolomite in the eggshells. This research resulted in the complete recognition of the structure of ostrich eggshells as well as the nature and extent of diagenesis in these eggshells which is vital for genetic and paleoenvironmental studies.