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Objective: Placental vascular reactivity (PlVR) indicates the ability of the placental vasculature to match blood supply to fetal demand. Many pregnancy disorders alter the characteristics of PlVR, resulting in suboptimal oxygen delivery, although current understanding is limited by the lack of non‐invasive, repeatable methods to measure PlVR in utero. Our objective was to quantify PlVR by measuring the placental response to transient changes in maternal carbon dioxide (CO2) using blood‐oxygen‐level‐dependent (BOLD) magnetic resonance imaging (MRI). We hypothesized that PlVR will increase with gestational age to meet the changing demands of a growing fetus, and that PlVR will be driven by a maternal response to changes in CO2 concentration. Methods: This was a cross‐sectional study of 35 women with a healthy singleton pregnancy, of whom 31 were included in the analysis. The median gestational age was 32.6 (range, 22.6–38.4) weeks. Pregnant women were instructed to follow audiovisual breathing cues during a MRI scan. Maternal end‐tidal CO2 (EtCO2) was measured concurrently with resting placental BOLD MRI for a total of 7–8 min. Preprocessing of magnetic resonance images consisted of manual delineation of placental anatomy and motion correction. In each placental voxel, vascular reactivity was computed using a coherence‐weighted general linear model between MRI signal and EtCO2 stimulus. Global PlVR was computed as the mean of voxel‐wise PlVR values across the placenta. Results: PlVR, quantified by the placental response to induced, transient changes in maternal CO2, was consistently measured in utero using BOLD MRI. PlVR increased non‐linearly with advancing gestational age (P < 0.001) and was higher on the fetal side of the placenta. PlVR was associated positively with fetal brain volume after accounting for gestational age. PlVR did not show any significant associations with maternal characteristics. Conclusions: We present, for the first time, a non‐invasive paradigm to quantify PlVR in ongoing human pregnancies without the use of exogenous gases or contrast agents. Our findings suggest that PlVR is driven by a fetal response to changes in maternal CO2. Ease of translation to the clinical setting makes PlVR a promising biomarker for the identification and management of high‐risk pregnancies. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology. [ABSTRACT FROM AUTHOR]

The waiting period of subplate evolution is a critical phase for the proper formation of neural connections in the brain. During this time, which corresponds to 15 to 24 postconceptual weeks (PCW) in the human fetus, thalamocortical and cortico-cortical afferents wait in and are in part guided by molecules embedded in the extracellular matrix of the subplate. Recent advances in fetal MRI techniques now allow us to study the developing brain anatomy in 3D from in utero imaging. We describe a reliable segmentation protocol to delineate the boundaries of the subplate from T2-W MRI. The reliability of the protocol was evaluated in terms of intra-rater reproducibility on a subset of the subjects. We also present the first 3D quantitative analyses of temporal changes in subplate volume, thickness, and contrast from 18 to 24 PCW. Our analysis shows that firstly, global subplate volume increases in proportion with the supratentorial volume; the subplate remained approximately one-third of supratentorial volume. Secondly, we found both global and regional growth in subplate thickness and a linear increase in the median and maximum subplate thickness through the waiting period. Furthermore, we found that posterior regions--specifically the occipital pole, ventral occipito-temporal region, and planum temporale--of the developing brain underwent the most statistically significant increases in subplate thickness. During this period, the thickest region was the developing somatosensory/motor cortex. The subplate growth patterns reported here may be used as a baseline for comparison to abnormal fetal brain development.

This research aimed to determine the bactericidal and cytotoxic properties of two mangrove plants commonly used in traditional medicine: Bruguiera cylindrica (leaf) and Rhizophora mucronata (stilt root). The selected plant parts were subjected to solvent polarity-based extraction. Of the solvent extracts, the acetone, ethyl acetate leaf extract of B. cylindrica and acetone stilt root extract of R. mucronata were chosen for further study as they exhibited minimum inhibitory and bactericidal concentrations between 0.5 and 1.0 mg.ml-1 against MTCC 435, Vibrio cholerae and Escherichia coli. The well and disk diffusion analysis of these mangrove extracts showed inhibition zone between 6 - 16 mm diameter for the bacterial pathogens. Similarly, the mangrove extracts displayed > 98 % reduction of viable counts for MTCC 435, E. coli and V. cholerae at different time intervals between 8 - 16 h. Electron microscope analyses of the bacterial cells treated with mangrove extracts confirmed the bactericidal properties by cellular aggregation and leakage. Further, the cytotoxicity evaluation of mangrove extracts with Henrietta Lacks cell lines did not show any viability interference up to 200 µg.ml-1, indicating their non-toxicity to human cells and biocompatibility for drug development. The research findings suggest that the acetone, ethyl acetate leaf extract of B. cylindrica and the acetone stilt root extract of R. mucronata could be used as a bactericidal resource against V. cholerae, MTCC 435 and E. coli. [ABSTRACT FROM AUTHOR]

The present study deals with a new version of power quasi Lindley distribution known as weighted power quasi Lindley distribution. Its different mathematical and statistical properties like moments, order statistics, reliability analysis, Renyi entropy, bonferroni and Lorenz curves have been presented. The parameters of proposed new distribution are estimated by employing the method of maximum likelihood estimation. Finally, a new distribution has been illustrated with three real lifetime data sets from medical sciences to examine its significance and supremacy. [ABSTRACT FROM AUTHOR]

Abstract Background Over the previous two decades, Plasmodium falciparum strains have become increasingly resistant to several medications. As a result, there is an urgent need to develop new therapeutic options. Taking this into account, we focused our research on screening microbial extracts from rhizosphere soil samples in specific regions, which increases the likelihood of discovering bacteria capable of producing antiplasmodial activity. Results In the current study, we aimed to isolate thirty-two different medicinal plant rhizosphere soil samples collected from Kolli Hills (January–December 2016). Isolation was performed on nutrient and starch casein agar medium by serial dilutions, and distinct colonies were chosen from each dilution. A total of two seventy-five bacterial isolates were isolated from the research plants and kept as pure cultures on nutrient agar. In which, maximum count of fourteen Gram-positive spore forming bacilli strains have been identified and further evaluated for morphological, cultural, and biochemical traits and significantly identified as Bacillus species. Further, promising anti-plasmodial action was demonstrated by B. megaterium bacterial extracts, with IC50 values of 24.65 µg/mL at 24 h and 7.82 µg/mL at 48 h. Bacillus mycoides showed good antiplasmodial activity with (IC50 P. falciparum 3D7: 23.52 μg/mL at 24 h and 22.88 μg/mL at 48 h, Bacillus flexus showed IC50 of 18.36 and 6.24 μg/mL and moderate antiplasmodial activity observed in Bacillus tequilensis. Poor antiplasmodial activity was found in Bacillus subtillis, Bacillus macerans, Bacillus pumilus and Bacillus larvey. Interestingly, 16S rRNA sequencing results confirmed that our bacterial species was Bacillus megaterium with 99% similarity observed with the accession number KX495303.1. Additionally, GC–MS analysis revealed effective anti-plasmodial bioactive compounds. Conclusions These findings show the potential of B. megaterium from Achyranthes aspera as a antiplasmodial agent. However, more research is needed to fully understand the bioactive compound of these strains and further studies are necessary to explore drug formulation and toxicity levels in the future.