Maturation Time Research Articles

Limited life‐history plasticity in marginal population of an invasive foundation species: Unraveling the genetic underpinnings and ecological implications

AbstractPlant's life history can evolve in response to variation in climate spatio‐temporally, but numerous multiple‐species studies overlook species‐specific (especially a foundation species) ecological effects and genetic underpinnings. For a species to successfully invade a region, likely to become a foundation species, life‐history variation of invasive plants exerts considerable ecological and evolutionary impacts on invaded ecosystems. We examined how an invasive foundation plant, Spartina alterniflora, varied in its life history along latitudinal gradient using a common gardens experiment. Two common gardens were located at range boundary in tropical zone and main distribution area of S. alterniflora in temperate zone in China. Within each population/garden, we measured the onset time of three successive phenological stages constituting the reproductive phase and a fitness trait. In the low‐latitude garden with higher temperature, we found that reproductive phase was advanced and its length prolonged compared to the high‐latitude garden. This could possibly due to lower plasticity of maturity time. Additionally, plasticity in the length of the reproductive phase positively related with fitness in the low‐latitude garden. Marginal population from tropic had the lowest plasticity and fitness, and the poor capacity to cope with changing environment may result in reduction of this population. These results reflected genetic divergence in life history of S. alterniflora in China. Our study provided a novel view to test the center–periphery hypothesis by integration across a plant's life history and highlighted the significance in considering evolution. Such insights can help us to understand long‐term ecological consequences of life‐history variation, with implications for plant fitness, species interaction, and ecosystem functions under climate change.

Enhanced electrophysiological activity and neurotoxicity screening of environmental chemicals using 3D neurons from human neural precursor cells purified with PSA-NCAM

The assessment of neurotoxicity for environmental chemicals is of utmost importance in ensuring public health and environmental safety. Multielectrode array (MEA) technology has emerged as a powerful tool for assessing disturbances in the electrophysiological activity. Although human embryonic stem cell (hESC)-derived neurons have been used in MEA for neurotoxicity screening, obtaining a substantial and sufficiently active population of neurons from hESCs remains challenging. In this study, we successfully differentiated neurons from a large population of human neuronal precursor cells (hNPC) purified using a polysialylated neural cell adhesion molecule (PSA-NCAM), referred to as hNPCPSA-NCAM+. The functional characterization demonstrated that hNPCPSA-NCAM+-derived neurons improve functionality by enhancing electrophysiological activity compared to total hNPC-derived neurons. Furthermore, three-dimensional (3D) neurons derived from hNPCPSA-NCAM+ exhibited reduced maturation time and enhanced electrophysiological activity on MEA. We employed subdivided population analysis of active mean firing rate (MFR) based on electrophysiological intensity to characterize the electrophysiological properties of hNPCPSA-NCAM+-3D neurons. Based on electrophysiological activity including MFR and burst parameters, we evaluated the sensitivity of hNPCPSA-NCAM+-3D neurons on MEA to screen both inhibitory and excitatory neuroactive environmental chemicals. Intriguingly, electrophysiologically active hNPCPSA-NCAM+-3D neurons demonstrated good sensitivity to evaluate neuroactive chemicals, particularly in discriminating excitatory chemicals. Our findings highlight the effectiveness of MEA approaches using hNPCPSA-NCAM+-3D neurons in the assessment of neurotoxicity associated with environmental chemicals. Furthermore, we emphasize the importance of selecting appropriate signal intensity thresholds to enhance neurotoxicity prediction and screening of environmental chemicals.

Few sex differences in regional gray matter volume growth trajectories across early childhood

Abstract Sex-specific developmental differences in brain structure have been documented in older children and adolescents, with females generally showing smaller overall brain volumes and earlier peak ages than males. However, sex differences in gray matter structural development in early childhood are less studied. We characterized sex-specific trajectories of gray matter volume development in children aged 2–8 years. We acquired anatomical magnetic resonance imaging (MRI) of the brain at the Alberta Children's Hospital in 123 typically developing children. Most children were scanned multiple times, for a total of 393 scans (mean = 3.2 scans/subject). We segmented T1-weighted structural MRI with MaCRUISE to define 116 regions and measured both absolute volumes (mm3) and proportional volumes (percent of intracranial volume). We characterized growth trajectories of gray matter volume for these brain regions between 2 and 8 years using mixed-effects models, showing volume increases, with most posterior and temporo-parietal regions peaking before 8 years. We found widespread main effects of sex, with males having larger volumes in 86% of brain regions. However, there were no significant sex differences in trajectories (age or age2 terms) for absolute volume. Proportional volumes of the right occipital fusiform gyrus and left medial postcentral gyrus showed significant age-by-sex interactions where females had steeper volume decreases than males. This study also confirms regional patterns observed in previous studies of older children, such as posterior-to-anterior timing of brain maturation. These results provide a comprehensive picture of gray matter volume development across early childhood, and suggest that sex differences do not emerge until later in development.

The study of potato hybrids in the Kola North

The article presents data on the study of potato varieties (2020–2022) in the Murmansk region on the basis of an integrated scientific research institution Murmansk State Agricultural Experimental Station – a branch of the VIR. In the trial dig, the hybrid 211/1 was isolated, which exceeded in all main indicators (yield, marketability, mass of tubers from one bush, mass of one tuber) the standard sample – the most adapted to the conditions of the Kola North (variety Elizabeth). There were good results in the main cleaning in terms of marketability: in 2020: hybrid 211/1 – 98.9%, hybrid 114/11 – 98.6, hybrid 2103/7 – 99.4, hybrid 211/9 – 99.4%; in 2021. – 211/1 – 98,1, 114/11 – 96,3, 2103/7 – 98,4, 211/9 – 99,1%; in 2022. -211/1 – 99,5, 114/11 – 99,8, 2103/7 – 99,2, 211/9 – 99%. In 2020 and 2021, the hybrid 211/1 stood out among the other four in terms of yield, marketability, weight of tubers from one bush, weight of one tuber. In 2022, hybrids 114/11 and 211/9 had the best yields. The mass of one tuber in the main harvest in 2022 for the hybrid 114/11 is 126.3 g (more than the standard). According to the maturation time, all samples are close to the standard. According to the research results, the most adapted hybrid 114/11 can be recommended to the population of the northern region.

Examining the Alterations in Metabolite Constituents and Antioxidant Properties in Mountain-Cultivated Ginseng (Panax ginseng C.A. Meyer) Organs during a Two-Month Maturation Period

The current research was the first to prove the existence of fluctuations in the metabolite constituents and antioxidant properties in different organs (leaves, stems, and roots) of the mountain-cultivated ginseng (MCG) plant during a two-month maturation period. Four metabolites, including fatty acids, amino acids, ginsenosides, and phenolic phytochemicals, exhibited considerable differences in organs and maturation times with the following order: leaves > stems > roots. The predominant metabolite contents were found in leaves, with fatty acid (1057.9 mg/100 g) on 31 May, amino acid (1989.2 mg/100 g) on 13 July, ginsenosides (88.7 mg/g) on 31 May, and phenolic phytochemical (638.3 μg/g) on 31 May. Interestingly, ginsenoside content in leaves were highest, with 84.8 → 88.7 → 82.2 → 78.3 mg/g. Specifically, ginsenosides Re, Rd, and F2 showed abundant content ranging from 19.1 to 16.9 mg/g, 8.5 to 14.8 mg/g, and 9.5 to 13.1 mg/g, respectively. Phenolic phytochemicals exhibited remarkable differences in organs compared to maturation periods, with the highest total phenolic content and total flavonoid content recorded at 9.48 GAE and 1.30 RE mg/g in leaves on 31 May. The antioxidant capacities on radical, FRAP, and DNA protection differed significantly, with leaves on 31 May exhibiting the highest values: 88.4% (DPPH), 89.5% (ABTS), 0.84 OD593 nm (FRAP) at 500 μg/mL, and 100% DNA protection at 50 μg/mL. Furthermore, principal cluster analysis revealed metabolite variability as follows: ginsenoside (83.3%) > amino acid (71.8%) > phenolic phytochemical (61.1%) > fatty acid (58.8%). A clustering heatmap highlighted significant changes in metabolite components under the maturation times for each organ. Our findings suggest that MCG leaves on 31 May may be a potential source for developing nutraceuticals, offering highly beneficial components and strong antioxidants.

Spatiotemporal Patterns of White Matter Maturation after Pre-Adolescence: A Diffusion Kurtosis Imaging Study.

Diffusion tensor imaging (DTI) enables the assessment of changes in brain tissue microstructure during maturation and ageing. In general, patterns of cerebral maturation and decline render non-monotonic lifespan trajectories of DTI metrics with age, and, importantly, the rate of microstructural changes is heterochronous for various white matter fibres. Recent studies have demonstrated that diffusion kurtosis imaging (DKI) metrics are more sensitive to microstructural changes during ageing compared to those of DTI. In a previous work, we demonstrated that the Cohen's d of mean diffusional kurtosis (dMK) represents a useful biomarker for quantifying maturation heterochronicity. However, some inferences on the maturation grades of different fibre types, such as association, projection, and commissural, were of a preliminary nature due to the insufficient number of fibres considered. Hence, the purpose of this follow-up work was to further explore the heterochronicity of microstructural maturation between pre-adolescence and middle adulthood based on DTI and DKI metrics. Using the effect size of the between-group parametric changes and Cohen's d, we observed that all commissural fibres achieved the highest level of maturity, followed by the majority of projection fibres, while the majority of association fibres were the least matured. We also demonstrated that dMK strongly correlates with the maxima or minima of the lifespan curves of DTI metrics. Furthermore, our results provide substantial evidence for the existence of spatial gradients in the timing of white matter maturation. In conclusion, our data suggest that DKI provides useful biomarkers for the investigation of maturation spatial heterogeneity and heterochronicity.

Early survival in Atlantic salmon is associated with parental genotypes at loci linked to timing of maturation.

Large effect loci often contain genes with critical developmental functions and potentially broad effects across life stages. However, their life stage-specific fitness consequences are rarely explored. In Atlantic salmon, variation in two large-effect loci, six6 and vgll3, is linked to age at maturity and several physiological and behavioral traits in early life. By genotyping the progeny of wild Atlantic salmon that were planted into natural streams with nutrient manipulations, we tested if genetic variation in these loci is associated with survival in early life. We found that higher early-life survival was linked to the genotype associated with late maturation in the vgll3, but with early maturation in the six6 locus. These effects were significant in high nutrients but not in low-nutrient streams. The differences in early survival were not explained by additive genetic effects in the offspring generation but by maternal genotypes in the six6 locus and by both parents' genotypes in the vgll3 locus. Our results suggest that indirect genetic effects of large-effect loci can be significant determinants of offspring fitness. This study demonstrates an intriguing case of how large-effect loci can exhibit complex fitness associations across life stages in the wild and indicates that predicting evolutionary dynamics is difficult.

Exploring crop maturity times as a conservation tool for improving resilience to human-elephant conflict: elephant crop-raiding

ABSTRACT The purpose of this study was to alleviate negative impacts of elephant crop-raiding faced by smallholder farmers around the Okavango delta. Although many studies have identified the relationship between crop-raiding and climatic factors, little attention was paid to aligning cropping duration to high rainfall. Therefore, this study aimed to investigate how crop maturity duration influences farmers’ vulnerability to elephant crop raiding and food loss. An experimental plot consisting of early and late maturing varieties of maize, sorghum and cowpea was set up and monitored in farms adjacent to corridors. Early maturing varieties yielded more (mean = 0.35 tha−1) than later maturing varieties (mean = 0.25 tha−1). The prolonged stay of crops in fields exposed them more to elephants (p < 0.001). Unlike late varieties, early varieties served as an evasion strategy by allowing earlier harvesting when there was adequate rainfall and elephants rarely frequented farms. Late maturing varieties were harvested at 16–19 weeks when elephants frequented the fields. This harvest timing significantly influences the vulnerability of crops to debilitating elephant raiding. This outcome suggests that policy reviews should incorporate more climate action into smallholder farming systems to strengthen SDG 1: no poverty and SDG 2: zero hunger, ease hostility toward elephants and improve elephant conservation.

Patients, healthcare providers, and general population preferences for hemodialysis vascular access: a discrete choice experiment.

A patient-centered dialysis treatment option requires an understanding of patient preferences for alternative vascular accesses and nephrologists often face difficulties when recommending vascular access to end-stage kidney disease (ESKD) patients. We aimed to quantify the relative importance of various vascular access characteristics to patients, healthcare providers and general population, and how they affect acceptability for patients and healthcare providers. In a discrete choice experiment, patients with maintenance hemodialysis (MHD), healthcare providers, and individuals from the general population were invited to respond to a series of hypothetical vascular access scenarios that differed in five attributes: cumulative patency, infection rate, thrombosis rate, cost, and time to maturation. We estimated the respondents' preference heterogeneity and relative importance of the attributes with a mixed logit model (MXL) and predicted the willingness to pay (WTP) of respondents via a multinomial logit model (MNL). Healthcare providers (n = 316) and the general population (n = 268) exhibited a favorable inclination toward longer cumulative patency, lower access infection rate and lower access thrombosis rate. In contrast, the patients (n = 253) showed a preference for a 3-year cumulative patency, 8% access infection rate, 35% access thrombosis rate and 1.5 access maturity time, with only the 3-year cumulative patency reaching statistical significance. Among the three respondent groups, the general population found cumulative patency less important than healthcare providers and patients did. Patients demonstrated the highest WTP for cumulative patency, indicating a willingness to pay an extra RMB$24,720(US$3,708) for each additional year of patency time. Patients and healthcare providers had a strong preference for vascular access with superior patency. While the general population preferred vascular access with lower thrombosis rates. These results indicate that most patients prefer autogenous arteriovenous fistula (AVF) as an appropriate choice for vascular access due to its superior patency and lower complications than other vascular access types.

An Integrated Testing Strategy (ITS) to assess the environmental compatibility of wood protection techniques

To quantify the possible impact of different wood protection techniques on the aquatic environment, we applied a tiered Integrated Testing Strategy (ITS) on leachates obtained from untreated (UTW) Norway spruce (Picea abies), specimens treated with a copper-ethanolamine-based preservative solution, complying with the Use Class 3 (UC3), and specimens thermally modified (TM). Different maturation times in water were tested to verify whether toxicant leaching is time-dependent. Tier I tests, addressing acute effects on Aliivibrio fischeri, Raphidocelis subcapitata, and Daphnia magna, evidenced that TM toxicity was comparable or even lower than in UTW. Conversely, UC3 significantly affected all species compared to UTW, also after 30 days of maturation in water, and was not considered an environmentally acceptable wood preservation solution. Tier II (effects on early-life stages of Lymnea auricularia) and III (chronic effects on D. magna and L. auricularia) performed on UTW and TM confirmed the latter as an environmentally acceptable treatment, with increasing maturation times resulting in decreased adverse effects. The ITS allowed for rapid and reliable identification of potentially harmful effects due to preservation treatments, addressed the choice for a less impacting solution, and can be effective for manufacturers in identifying more environmentally friendly solutions while developing their products.

Improved Ultrasound-Guided Balloon-Assisted Maturation Angioplasty Using Drug-Eluting Balloons in the First Autogenous Arteriovenous Fistula Procedure: Early Experience.

In patients with end-stage renal failure requiring hemodialysis, autogenous arteriovenous fistula (AVF) is preferred over tunneled dialysis catheters due to lower complications and costs. However, AVF maturation failure remains a common issue due to small vein size, multiple venipunctures, and other factors. Guidelines recommend using vessels of >2 mm for forearm AVFs and >3 mm for upper arm AVFs. This study investigates the use of intraoperative Doppler ultrasound (DUS)-guided Balloon-Assisted Maturation (BAM) with drug-eluting balloons (DEB) during initial AVF creation. Data from 114 AVF procedures, of which 27.2% underwent BAM, were analyzed. BAM was performed in 25 distal radio-cephalic and 6 proximal brachio-cephalic AVFs. With DUS guidance, vein stenosis was identified and treated using DEB. Technical success was achieved in all cases, with no early mortality. Early BAM-related complications were minimal, and no AVF thrombosis occurred. AVF maturation time was 15 days (SD: 3), and no further complications were reported during a mean follow-up of 10.38 months. Using BAM with DEB during AVF creation led to successful maturation and dialysis use without the need for secondary procedures. This study emphasizes the importance of identifying AVF failure risk early and utilizing DUS-guided procedures to enhance AVF outcomes. A more liberal use of intraoperative BAM could limit reinterventions in patients undergoing AVFs.

Evaluation of Agronomic and Oil Characteristics of Selected Turkish Poppy Genotypes under Ankara’s Climate Conditions

Poppy is a minor agronomic field crop that is cultivated under a UN license. It is known for its alkaloids and seeds, and, rarely, for the latter’s use in ethnomedicine. Changing climate conditions could lead to the need for alternate areas for poppy cultivation in Türkiye. This experiment was conducted in Ankara, which is not a poppy production area. The morphological characteristics and oil characteristics of 19 Turkish poppy genotypes were determined over two years. According to the results, the emergence time was between 10 and 22 days, the flowering time ranged from 197 to 214 days, while the harvest maturation time was between 250 and 269 days. The plant height varied from 75.8 to 97.5 cm, the weight of 1000 seeds ranged from 305.0 to 428.0 mg, and the weight of the seeds per plant was between 2.95 and 5.78 g. Furthermore, the yield ranged from 100.7 to 202.3 kg da−1, the fat content was between 38.8 and 44.1%, and the protein content ranged from 15.9 to 18.4%. The linoleic acid content ranged from 66.77% to 75.60%, the oleic acid content ranged from 10.78% to 19.46%, and the palmitic acid content ranged from 8.38% to 9.90%. The highest yield in Ankara was obtained from the Çelikoğlu cultivar.

Reorganization of dopamine circuitry in the anterior corpus callosum between early adolescence and adulthood in the mouse.

The maturation of forebrain dopamine circuitry occurs over multiple developmental periods, extending from early postnatal life until adulthood, with the precise timing of maturation defined by the target region. We recently demonstrated in the adult mouse brain that axon terminals arising from midbrain dopamine neurons innervate the anterior corpus callosum and that oligodendrocyte lineage cells in this white matter tract express dopamine receptor transcripts. Whether corpus callosal dopamine circuitry undergoes maturational changes between early adolescence and adulthood is unknown but may be relevant to understanding the dramatic micro- and macro-anatomical changes that occur in the corpus callosum of multiple species during early adolescence, including in the degree of myelination. Using quantitative neuroanatomy, we show that dopamine innervation in the forceps minor, but not the rostral genu, of the corpus callosum, is greater during early adolescence (P21) compared to adulthood (>P90) in wild-type mice. We further demonstrate with RNAscope that, as in the adult, Drd1 and Drd2 transcripts are expressed at higher levels in oligodendrocyte precursor cells (OPCs) and decline as these cells differentiate into oligodendrocytes. In addition, the number of OPCs that express Drd1 transcripts during early adolescence is double the number of those expressing the transcript during early adulthood. These data further implicate dopamine in axon myelination and myelin regulation. Moreover, because developmental (activity-independent) myelination peaks during early adolescence, with experience-dependent (activity-dependent) myelination greatest during early adulthood, our data suggest that potential roles of dopamine on callosal myelination shift between early adolescence and adulthood, from a developmental role to an experience-dependent role.

Impact of sulfur compounds on motorbike wheel damper rubber manufacturing materials with 3 Phr, 4 Phr, and 6 Phr compositions

Rubber force is a simple but important thing for vehicles. This component is located in the rear wheel drum which is directly connected to the gear. Many factors influence the damage to this component. This research aims to determine how much influence stearic acid has on the hardness and tensile strength values of the lifting rubber compound. The materials used to make the compound are rubber smoked sheet (RSS) and synthetic rubber mixed with the chemicals stearic acid, black carbon white oil, ZnO, paraffin wax, MBTS, comaron resin and sulfur. These ingredients are mixed using two roll mixing until they combine and form a compound sheet. To determine the maturation time of rubber, a rheometer process is carried out. The next process is vulcanization of rubber using a mold that is pressed at a temperature of 1600C and a pressure of 150 psi. Tensile testing uses rubber testing equipment with SNI ISO 37: 2015 (IDT–2011) standards. Hardness testing uses a tool with a Shore A hardness tester scale with ISO 7619–1:2010 standards. Based on the results of the tests carried out, the addition of sulfur has a very significant effect on the hardness value and tensile strength value. For the hardness value of compound 3 with a sulfur composition of 6 phr, it has the highest hardness, namely 77 Shore A and the lowest value is composition 1 with a hardness value of 65.6 Shore A. The highest tensile strength value is 15,394 N/mm2 in composition 1 and the lowest value is in composition 3 with a value of 11.44 N/mm2

Distal Forearm Arteriovenous Fistula Maturation in Diabetic Hemodialysis Patients.

Atherosclerotic disease of the forearm arteries can impede the maturation of distal fistulas in diabetic patients. The goal of this study was to look at the maturity of diabetic hemodialysis patients' distal forearm (radiocephalic snuffbox or distal forearm) arteriovenous fistulas. Patients with chronic renal failure who were candidates for distal forearm radiocephalic arteriovenous fistula implantation were evaluated in this cross-sectional study. Patients' demographic details, underlying disorders, laboratory measurements, vital signs, and information on their surgery were all noted. Patients were checked for fistula development 1 week, 1 month, 2months, and then monthly until 6 months after surgery. Arteriovenous fistula maturation characterized by optimal blood flow, vessel dilation, and structural adaptations. Among 343 patients (56% male, 44% female, mean age: 57.32 ± 12.48years), hypertension prevailed (81.9%), followed by hyperlipidemia (42.3%) and coronary artery disease history (25.9%). AVFs achieved 58.3% maturation in 64.98 ± 11.05days; higher BP during creation correlated with successful maturation (17.02 ± 1.46mmHg vs 13.90 ± 1.93mmHg, P < .05). No significant statistical difference found in distal forearm arteriovenous fistula maturation between males (57.8%) and females (58.9%) (P > .005). However, 41.7% of AVFs failed in 18.83 ± 17.89days. Failed AVFs exhibited lower BP during operation and failure (11.75 ± 1.86mmHg). Kaplan-Meier analysis depicted maturation probabilities over 90 days post-surgery. Diabetes and patient sex did not affect the maturation time of distal forearm AVFs in hemodialysis patients. Increased blood pressure during and after surgery correlated with shorter maturation time.

Hierarchical Self-Assembly of Nano- and Microstructures of Zinc Oxide in Combined Sol-Gel Systems

Using the methods of optical spectrometry and IR spectroscopy, the processes of self-assembly of nano- and microstructures of zinc oxide in combined sol-gel systems obtained by mixing film-forming sols with different maturation times were studied. Characteristic bands and absorption peaks in the IR spectra were established, demonstrating an unambiguous relationship between the IR transmittance — radiation and maturation time for different volumetric ratios of mixed sols. It has been shown that experimental IR spectroscopy data correlate with optical spectrometry data in the visible and UV radiation range. The correspondence of ZnO films formed on the basis of combined sol-gel systems to the tasks of nanostructural engineering has been demonstrated.

Height growth of Mexican boys by geographic region: an evaluation based on nationally representative data of ENSANUT 2012 and 2018.

Existing research on human growth in Mexico is regionally focused, creating a gap in the understanding of growth patterns of children and adolescents at national level and regional variation. The objective of the present study was to characterize the height growth curve of the Mexican population by geographic area and to cluster the states of the Mexican Republic according to their somatic maturation characteristics, based on a national representative sample of boys. Data on age, height, socioeconomic level, and geographic area of 18,219 boys were obtained from the National Health and Nutrition Survey 2012 (ENSANUT) and ENSANUT 2018, carried out in 32 Mexican states. Both surveys had representative samples. Preece-Baines 1 model was applied to fit height growth curves. Biological parameters were estimated; principal component analysis and cluster analysis were performed to group Mexican states based on these biological parameters. The estimated age at peak height velocity (PHV) was 12.3 years in the sample. Significant regional differences in the timing and tempo of PHV among Mexican boys were observed. Boys in the northern region experienced PHV at an earlier age and had a shorter duration of growth compared with boys in the central and southern regions. Boys in the central region had a longer duration of growth and a later age of PHV compared with the boys in the southern region. The cluster that included the southern states of the country showed estimated lower adult height and earlier somatic maturation. A lower height was found in the low and low-middle socioeconomic levels compared with the medium-high and high socioeconomic levels. Future research in Mexico should focus on longitudinal studies to analyse the timing and tempo of growth and maturation, considering the impacts of environmental and genetic factors. Public health strategies should account for geographic variations.

Human oligodendrocyte-like cell differentiation is promoted by TSPO-mediated endogenous steroidogenesis

Mature oligodendrocytes (OLs) arise from oligodendrocyte precursor cells that, in case of demyelination, are recruited at the lesion site to remyelinate the axons and therefore restore the transmission of nerve impulses. It has been widely documented that exogenously administered steroid molecules are potent inducers of myelination. However, little is known about how neurosteroids produced de novo by OLs can impact this process.Here, we employed a human OL precursor cell line to investigate the role of de novo neurosteroidogenesis in the regulation of OLs differentiation, paying particular attention to the 18 kDa Translocator Protein (TSPO) which controls the rate-limiting step of the neurosteroidogenic process. Our results showed that, over the time of OL maturation, the availability of cholesterol, which is the neurosteroidogenesis initial substrate, and key members of the neurosteroidogenic machinery, including TSPO, were upregulated. In addition, OLs differentiation was impaired following neurosteroidogenesis inhibition and TSPO silencing. On the contrary, TSPO pharmacological stimulation promoted neurosteroidogenic function and positively impacted differentiation.Collectively, our results suggest that de novo neurosteroidogenesis is actively involved in the autocrine and paracrine regulation of human OL differentiation. Moreover, since TSPO was able to promote OL differentiation through a positive modulation of the neurosteroid biosynthetic process, it could be exploited as a promising target to tackle demyelinating diseases.

A comparative study on the vector competence of Anopheles stephensi from geographically distinct malarious and non-malarious urban areas in India to the malarial parasite, Plasmodium vivax.

Anopheles stephensi is responsible for the transmission of malaria in urban areas. Vector competence of An. stephensi from a non-malarious (Coimbatore) and highly malarious (Chennai) urban area were investigated to find out the reason for the non-transmission of malaria in Coimbatore. Vector competence (Susceptibility/refractoriness) of An. stephensi mosquitoes from Chennai (Malarious) and Coimbatore (Non-malarious), Tamil Nadu, India to Plasmodium vivax (Chennai) were investigated. Bioassays were carried out concurrently in both these strains by artificial membrane feeding technique using the same malaria infected blood. An. stephensi were dissected to observe infection in the midgut and salivary glands. The parasite infection, oocyst and sporozoite positivity rate, the oocyst load, correlation between male-female gametocyte ratio and infection, and Survival Analysis of parasitic stages during sporogony were analyzed and compared. The overall infection rate was 45.8 and 41.2 per cent in Chennai and Coimbatore. Oocyst count ranged from 1-80 and 1-208 respectively and not statistically significant. Oocyst positivity was high from Day 8-21in both strains. The Mean Survival Day (MSD) for oocyst was Day 14 in both strains. Sporozoite was observed in four experiments in each of the strains and the MSD for sporozoites was Day 20 and Day 17 in Chennai and Coimbatore. An. stephensi of Chennai and Coimbatore are equally susceptible to P. vivax infection and the non-transmission of malaria in Coimbatore can be attributed to external factors such as the presence of preferential breeding habitat, vector density, vector survival, and weather. The only difference observed was the comparatively shortened oocyst maturation time in the Coimbatore strain which requires further investigation.

Minimizing delays to hemodialysis access maturation: A quality improvement analysis.

Pre-operative process optimization can expedite time-to-intervention and reduce overall health care costs. We hypothesized that the longest delay to hemodialysis (HD) access creation would be from pre-operative vessel mapping (mandatory in our practice), and that this would be correlated with increased catheter days. One hundred thirty patients (24 inpatients, 106 outpatients) who received initial hemodialysis (HD) access from 01/01/2017 to 12/31/2021, at the Veterans Affairs Puget Sound, Seattle, Washington, were identified. Median time differences between pre-operative events were compared between inpatients and outpatients using the Mann-Whitney U test. Outpatients were then stratified by time of catheter-based HD initiation (no catheter, pre-referral catheter, post-referral catheter) and compared. The impacts of mapping-related delays on catheter use were evaluated using regression. Inpatients had shorter referral to access maturation times (125 days inpatient vs 146 days outpatient; p = 0.03). This was driven by shorter referral to mapping (2 days inpatient vs 27 days outpatient; p < 0.01) and mapping to pre-surgical evaluation (1-day inpatient vs 6 days outpatients; p < 0.01) times. Pre-surgical evaluation to OR times represented the longest pre-operative delay in both groups (51 days inpatient vs 29 days outpatient; p = 0.59). Among outpatients, tunneled catheter placement post-referral resulted in longer maturation times (74 days no catheter vs 67 days pre-referral vs 149 days post-referral; p < 0.01) but not additional pre-operative delays. No trend existed between increased mapping times and catheter-based dialysis duration (R2 = 0.08). Preoperative vein mapping contributed up to 21% of referral to maturation times but was not associated with increased tunneled catheter duration. While tunneled catheter placement impacted access maturation it did not cause additional pre-operative delays. Earlier referrals for access creation and reduction of outpatient wait-time from referral to OR and increased AV graft placement may minimize catheter days in our system thereby mitigating the added delays caused by pre-operative vein mapping.