Mechanisms of vacuolar phosphate efflux supporting soybean root hair growth in response to phosphate deficiency.

Phosphorus is an essential macronutrient for plant growth and development. In response to phosphate (Pi) deficiency, plants rapidly produce a substitutive amount of root hairs; however, the mechanisms underlying Pi supply for root hair growth remain unclear. Here, we observed that soybean (Glycine max) plants maintain a consistent level of Pi within root hairs even under external Pi deficiency. We therefore investigated the role of vacuole-stored Pi, a major Pi reservoir in plant cells, in supporting root hair growth under Pi-deficient conditions. Our findings indicated that two vacuolar Pi efflux (VPE) transporters, GmVPE1 and GmVPE2, remobilize vacuolar stored Pi to sustain cytosolic Pi content in root hair cells. Genetic analysis showed that double mutants of GmVPE1 and GmVPE2 exhibited reduced root hair growth under low Pi conditions. Moreover, GmVPE1 and GmVPE2 were highly expressed in root hairs, with their expression levels significantly upregulated by low Pi treatment. Further analysis revealed that GmRSL2 (ROOT HAIR DEFECTIVE 6-like 2), a transcription factor involved in root hair morphogenesis, directly binds to the promoter regions of GmVPE1 and GmVPE2, and promotes their expressions under low Pi conditions. Additionally, mutants lacking both GmRSL2 and its homolog GmRSL3 exhibited impaired root hair growth under low Pi stress, which was rescued by overexpressing either GmVPE1 or GmVPE2. Taken together, our study has identified a module comprising vacuolar Pi exporters and transcription factors responsible for remobilizing vacuolar Pi to support root hair growth in response to Pi deficiency in soybean.

A machine learning-based procedure for leveraging clickstream data to investigate early predictability of failure on interactive tasks.

Early detection of risk of failure on interactive tasks comes with great potential for better understanding how examinees differ in their initial behavior as well as for adaptively tailoring interactive tasks to examinees' competence levels. Drawing on procedures originating in shopper intent prediction on e-commerce platforms, we introduce and showcase a machine learning-based procedure that leverages early-window clickstream data for systematically investigating early predictability of behavioral outcomes on interactive tasks. We derive features related to the occurrence, frequency, sequentiality, and timing of performed actions from early-window clickstreams and use extreme gradient boosting for classification. Multiple measures are suggested to evaluate the quality and utility of early predictions. The procedure is outlined by investigating early predictability of failure on two PIAAC 2012 Problem Solving in Technology Rich Environments (PSTRE) tasks. We investigated early windows of varying size in terms of time and in terms of actions. We achieved good prediction performance at stages where examinees had, on average, at least two thirds of their solution process ahead of them, and the vast majority of examinees who failed could potentially be detected to be at risk before completing the task. In-depth analyses revealed different features to be indicative of success and failure at different stages of the solution process, thereby highlighting the potential of the applied procedure for gaining a finer-grained understanding of the trajectories of behavioral patterns on interactive tasks.

Socio-economic inequalities in children's nutritional status in Democratic Republic of the Congo in 2017-2018: an analysis of data from a nationally representative survey.

OBJECTIVE: The Democratic Republic of the Congo (DRC) has one of the highest levels of child undernutrition globally; however, little information exists on the underlying socio-economic inequalities resulting in undernutrition. This study aims to examine the differences in the nutritional statuses of children across different wealth quintiles and explores the association between malnutrition in children and related factors. DESIGN: We utilised the 2018 Multiple Indicator Cluster Survey data. We estimated the prevalence of malnutrition across all twenty-six provinces. The study used the WHO 2006 child growth standards to measure stunting, underweight and wasting. We employed a mixed-effect linear model to analyse the association between nutritional status and healthcare accessibility, domestic sanitation, and socio-demographic factors. SETTING: Twenty-six provinces in the DRC. PARTICIPANTS: 21 477 children under 5 years of age and 21 828 women of childbearing age in the DRC. RESULTS: The national prevalence of underweight, stunting and wasting was found to be 23·33 %, 42·05 % and 5·66 %, respectively. Household wealth and mother's education level were significantly positively associated with the nutritional statuses of children. Among households in the lowest wealth quintile, residence in urban areas was a protective factor against undernutrition. CONCLUSION: The findings of this study indicate considerable socio-economic inequalities in the nutritional statuses of children under 5 years of age in the DRC, highlighting the need for nutrition promotion as part of maternal and child healthcare. Interventions and policies should include improving nutrition education for less-educated mothers, in particular, in the central provinces of the DRC.

Synthesis and Biological Evaluation of Celastrol Derivatives with Improved Cytotoxic Selectivity and Antitumor Activities.

Cdc37 associates kinase clients to Hsp90 and promotes the development of cancers. Celastrol, a natural friedelane triterpenoid, can disrupt the Hsp90-Cdc37 interaction to provide antitumor effects. In this study, 31 new celastrol derivatives, 2a-2d, 3a-3g, and 4a-4t, were designed and synthesized, and their Hsp90-Cdc37 disruption activities and antiproliferative activities against cancer cells were evaluated. Among these compounds, 4f, with the highest tumor cell selectivity (15.4-fold), potent Hsp90-Cdc37 disruption activity (IC50 = 1.9 µM), and antiproliferative activity against MDA-MB-231 cells (IC50 = 0.2 µM), was selected as the lead compound. Further studies demonstrated 4f has strong antitumor activities both in vitro and in vivo through disrupting the Hsp90-Cdc37 interaction and inhibiting angiogenesis. In addition, 4f exhibited less toxicity than celastrol and showed a good pharmacokinetics profile in vivo. These findings suggest that 4f may be a promising candidate for development of new cancer therapies.

Trends of maternal health service coverage in the Democratic Republic of the Congo: a pooled cross-sectional study of MICS 2010 to 2018.

BACKGROUND: Maternal health services are essential for reducing maternal and newborn mortality. However, maternal health service status in the Democratic Republic of the Congo (DRC) remains poorly understood. This study aims to explore the trends of antenatal care (ANC) and skilled birth attendance coverage in the past decade in the DRC. METHODS: The 13,361 participants were from two rounds of Multiple Indicators Cluster Survey (MICS) conducted by the National Institute of Statistics of the Ministry of Planning of the DRC, in collaboration with the United Nations Children's Fund (UNICEF), in 2010 and 2017-2018. A regression-based method was adopted to calculate adjusted coverage of ANC and skilled birth attendance. Subgroup analysis based on different socioeconomic status (SES) was conducted to explore the impact of domestic conflicts. RESULTS: From 2010 to 2018, the overall weighted ANC coverage in the DRC declined from 87.3 % (95 % CI 86.1-88.0 %) to 82.4 % (95 % CI 81.1-84.0 %), while the overall weighted skilled birth attendance coverage increased from 74.2 % (95 % CI 72.5-76.0 %) to 85.2 % (95 % CI 84.1-86.0 %). Adjusted ANC coverage and adjusted skilled birth attendant coverage both declined in Kasai Oriental, but increased in Nord Kivu and Sud Kivu. In Kasai Occidental, ANC coverage declined, but skilled birth coverage increased. In the Kasai region, the largest decline in adjusted coverage of ANC was found among the poorest women. However, in the Kivu region, both the adjusted coverage of ANC and skilled birth attendance increased among the poorest women. CONCLUSIONS: Due to ongoing conflicts, there has been a systemic deterioration of maternal healthcare coverage in some regions of the DRC, particularly among people with low SES. However, in other regions, maternal healthcare services were not severely disrupted possibly due to substantial international health assistance.

The effect of health insurance on crime: Evidence from the Affordable Care Act Medicaid expansion.

Little evidence exists on the effect of the Affordable Care Act (ACA) on criminal behavior, a gap in the literature that this paper seeks to address. Using a simple model, we argue we should anticipate a decrease in time devoted to criminal activities in response to the expansion, because the availability of the ACA Medicaid coverage raises the opportunity cost of crime. This prediction is particularly relevant for the ACA expansion because it primarily affects childless adults, a population likely to contain individuals who engage in criminal behavior. We validate this forecast empirically using a difference-in-differences framework, estimating the expansion's effects on panel datasets of state- and county-level crime rates. Our estimates suggest that the ACA Medicaid expansion was negatively associated with burglary, vehicle theft, homicide, robbery, and assault. These crime-reduction spillover effects represent an important offset to the government's cost burden for the ACA Medicaid expansion.

Synthesis and Biological Evaluation of Celastrol Derivatives as Potential Immunosuppressive Agents.

Celastrol, a friedelane-type triterpenoid isolated from the genus Triperygium, possesses antitumor, anti-inflammatory, and immunosuppressive activities. A total of 42 celastrol derivatives (1a-1t, 2a-2l, and 3a-3j) were synthesized and evaluated for their immunosuppressive activities. Compounds 2a-2e showed immunosuppressive effects, with IC50 values ranging from 25 to 83 nM, and weak cytotoxicity (CC50 > 1 µM). Compound 2a, with a selectivity index value 31 times higher than that of celastrol, was selected as a lead compound. Further research showed that 2a exerted its immunosuppressive effects by inducing apoptosis and inhibiting cytokine secretion via Lck- and ZAP-70-mediated signaling pathways.

Atropisomeric meroterpenoids with rare triketone-phloroglucinol-terpene hybrids from Baeckea frutescens.

Baefrutones A-F (1-6), six new meroterpenoids with rare triketone-phloroglucinol-monoterpene/sesquiterpene frameworks, together with their biosynthetically related intermediate (±)-baeckenon B (7), were isolated from the aerial part of Baeckea frutescens under the guidance of HPLC-Q/TOF-MS2 investigation. Compounds 1-4 represent the first examples of natural meroterpenoids existing as four pairs of inseparable diastereomeric atropisomers (2 : 1, 1H NMR integration) caused by the restricted rotation around the C-6-C-7-C-1' bonds arising from the intramolecular hydrogen bond between C-1 carbonyl and 2'-OH. The discovery of these architectures not only largely enriched the chemodiversity of the meroterpenoid and atropisomer library, but also might be exciting and challenging for asymmetric organic synthesis. Their structures and absolute configurations were established by extensive spectroscopic analysis, X-ray diffraction, and ECD calculations. Compounds 5 and 6 were biomimetically synthesized from 7 and ß-caryophyllene via a regioselective oxidative hetero-Diels-Alder reaction, thus providing access to the construction of the 6/6/9/4 tetracyclic ring system. The anti-inflammatory activities of these meroterpenoids were also discussed.

Frutescone A-G, Tasmanone-Based Meroterpenoids from the aerial parts of Baeckea frutescens.

Frutescone A-G [(1-6), (+)-7, (-)-7], a new group of naturally occurring tasmanone-based meroterpenoids, were isolated from the aerial parts of Baeckea frutescens L. Compounds 1 and 4 featured a rare carbon skeleton with an unprecedented oxa-spiro[5.8] tetradecadiene ring system, existing as two favored equilibrating conformers in CDCl3 solution, identified by variable-temperature NMR. The regioselective syntheses of 4-7 were achieved in a concise manner by a biomimetically inspired key hetero-Diels-Alder reaction "on water". Compounds 1, 4, and 5 exhibited moderate cytotoxicities in vitro.

Anti-inflammatory Meroterpenoids from Baeckea frutescens.

Frutescones H-R (1-11), new sesqui- or monoterpene-based meroterpenoids, were isolated from the aerial parts of Baeckea frutescens. Their structures and absolute configurations were established by means of spectroscopic analyses (HRESIMS, 1D and 2D NMR, and ECD), as well as single-crystal X-ray crystallography of 1, (-)-7, and 9. The anti-inflammatory activities of all isolates were evaluated by measuring their inhibitory effects on NO production in LPS-stimulated RAW 264.7 macrophages, and the structure-activity relationships of 1-11 are also discussed. Compound 8 exhibited anti-inflammatory activity with an IC50 value of 0.36 µM, which might be related to the regulation of the NF-κB signaling pathway via the suppression of p65 nuclear translocation and the consequent decrease of IL-6 and TNF-α.

Explanatory Cognitive Diagnosis Models Incorporating Item Features.

Item quality is crucial to psychometric analyses for cognitive diagnosis. In cognitive diagnosis models (CDMs), item quality is often quantified in terms of item parameters (e.g., guessing and slipping parameters). Calibrating the item parameters with only item response data, as a common practice, could result in challenges in identifying the cause of low-quality items (e.g., the correct answer is easy to be guessed) or devising an effective plan to improve the item quality. To resolve these challenges, we propose the item explanatory CDMs where the CDM item parameters are explained with item features such that item features can serve as an additional source of information for item parameters. The utility of the proposed models is demonstrated with the Trends in International Mathematics and Science Study (TIMSS)-released items and response data: around 20 item linguistic features were extracted from the item stem with natural language processing techniques, and the item feature engineering process is elaborated in the paper. The proposed models are used to examine the relationships between the guessing/slipping item parameters of the higher-order DINA model and eight of the item features. The findings from a follow-up simulation study are presented, which corroborate the validity of the inferences drawn from the empirical data analysis. Finally, future research directions are discussed.

It's about time! Exploring time allocation patterns of adults with lower literacy skills on a digital assessment.

Introduction: Despite the necessity for adults with lower literacy skills to undergo and succeed in high-stakes computer-administered assessments (e.g., GED, HiSET), there remains a gap in understanding their engagement with digital literacy assessments. Methods: This study analyzed process data, specifically time allocation data, from the Program for the International Assessment of Adult Competencies (PIAAC), to investigate adult respondents' patterns of engagement across all proficiency levels on nine digital literacy items. We used cluster analysis to identify distinct groups with similar time allocation patterns among adults scoring lower on the digital literacy assessment. Finally, we employed logistic regression to examine whether the groups varied by demographic factors, in particular individual (e.g., race/ethnicity, age) and contextual factors (e.g., skills-use at home). Results: Adults with lower literacy skills spent significantly less time on many of the items than adults with higher literacy skills. Among adults with lower literacy skills, two groups of time allocation patterns emerged: one group (Cluster 1) exhibited significantly longer engagement times, whereas the other group (Cluster 2) demonstrated comparatively shorter durations. Finally, we found that adults who had a higher probability of Cluster 1 membership (spending more time) exhibited relatively higher literacy scores, higher self-reported engagement in writing skills at home, were older, unemployed, and self-identified as Black. Discussion: These findings emphasize differences in digital literacy engagement among adults with varying proficiency levels. Additionally, this study provides insights for the development of targeted interventions aimed at improving digital literacy assessment outcomes for adults with lower literacy skills.

Enhancement of de novo lipogenesis by the IDH1 and IDH2-dependent reverse TCA cycle maintains the growth and angiogenic capacity of bone marrow-derived endothelial progenitor cells under hypoxia.

BACKGROUND: Bone marrow-derived endothelial progenitor cells (EPCs) play a dynamic role in maintaining the structure and function of blood vessels. But how these cells maintain their growth and angiogenic capacity under bone marrow hypoxic niche is still unclear. This study aims to explore the mechanisms from a perspective of cellular metabolism. METHODS: XFe96 Extracellular Flux Analyzer was used to analyze the metabolic status of EPCs. Gas Chromatography-Mass Spectrometry (GC-MS) was used to trace the carbon movement of 13C-labeled glucose and glutamine under 1 % O2 (hypoxia) and ∼20 % O2 (normoxia). Moreover, RNA interference, targeting isocitrate dehydrogenase-1 (IDH1) and IDH2, was used to inhibit the reverse tricarboxylic acid (TCA) cycle and analyze metabolic changes via isotope tracing as well as changes in cell growth and angiogenic potential under hypoxia. The therapeutic potential of EPCs under hypoxia was investigated in the ischemic hindlimb model. RESULTS: Compared with normoxic cells, hypoxic cells showed increased glycolysis and decreased mitochondrial respiration. Isotope metabolic tracing revealed that under hypoxia, the forward TCA cycle was decreased and the reverse TCA cycle was enhanced, mediating the conversion of α-ketoglutarate (α-KG) into isocitrate/citrate, and de novo lipid synthesis was promoted. Downregulation of IDH1 or IDH2 under hypoxia suppressed the reverse TCA cycle, attenuated de novo lipid synthesis (DNL), elevated α-KG levels, and decreased the expression of hypoxia inducible factor-1α (HIF-1α) and vascular endothelial growth factor A (VEGFA), eventually inhibiting the growth and angiogenic capacity of EPCs. Importantly, the transplantation of hypoxia-cultured EPCs in a mouse model of limb ischemia promoted new blood vessel regeneration and blood supply recovery in the ischemic area better than the transplantation of normoxia-cultured EPCs. CONCLUSIONS: Under hypoxia, the IDH1- and IDH2-mediated reverse TCA cycle promotes glutamine-derived de novo lipogenesis and stabilizes the expression of α-KG and HIF-1α, thereby enhancing the growth and angiogenic capacity of EPCs.

Does armed conflict lead to lower prevalence of maternal health-seeking behaviours: theoretical and empirical research based on 55 683 women in armed conflict settings.

BACKGROUND: Women and children bear a substantial burden of morbidity and mortality due to armed conflict. Life-saving maternal and child health (MCH) services are low-quality in most conflict-affected regions. Previous studies on armed conflict and MCH services have been mostly cross-sectional, and a causal relationship between armed conflict and MCH services utilisation cannot be inferred. METHODS: First, we constructed a utility equation for maternal health-seeking behaviour. Next, we extracted MCH data from the Multiple Indicator Cluster Survey led by the UNICEF. Armed conflict data were obtained from the Uppsala Conflict Data Programme; 55 683 women aged 15-49 from Chad, the Central African Republic, the Democratic Republic of Congo (DRC) and the Republic of Iraq were selected as participants. We fitted a difference-in-differences (DID) model, taking before or after the conflict started as an exposure variable to estimate the effects of armed conflict on maternal health-seeking behaviours. RESULTS: According to the results of the DID model, in the regional sample, armed conflict had a positive effect on tetanus vaccination (ß=0.055, 95% CI 0.004 to 0.106, p<0.05), and had a negative effect on antenatal care at least eight visits (ANC8+) (ß=-0.046, 95% CI -0.078 to -0.015, p<0.01). And, the effects of armed conflict on ANC, ANC4+, institutional delivery and early initiation of breast feeding (EIB) were not statistically significant. As for the country sample, we found that armed conflict had a negative effect on EIB (ß=-0.085, 95% CI -0.184 to 0.015, p<0.1) in Chad. In Iraq, armed conflict had positive impacts on ANC (ß=0.038, 95% CI -0.001 to 0.078, p<0.1) and tetanus vaccination (ß=0.059, 95% CI 0.012 to 0.107, p<0.05), whereas it had a negative effect on ANC8+ (ß=-0.039, 95% CI -0.080 to 0.002, p<0.1). No statistically significant associations were discovered in DRC based on the DID model. CONCLUSIONS: There might be a mixed effect of armed conflict on maternal health-seeking behaviours. In the absence of humanitarian assistance, armed conflict reduces certain maternal health-seeking behaviours, such as ANC8+. When practical humanitarian health assistance is provided, the damage can be alleviated, and even the prevalence of maternal health-seeking behaviours can be improved, such as tetanus vaccination. Providing humanitarian assistance to conflict-affected regions improved the accessibility of MCH services for women living in those areas. However, the goals of saving lives and alleviating suffering still need to be achieved. In conflict-affected regions, humanitarian assistance on ANC, institutional delivery and breast feeding need strengthening.

Trends in socioeconomic inequalities in malnutrition among children under 5 in the Democratic Republic of the Congo from 2001 to 2018.

OBJECTIVE: Malnutrition in the Democratic Republic of the Congo (DRC) has declined over the past 2 decades. However, malnutrition inequality persists. Evaluating trends of socioeconomic disparities in malnutrition among children under 5 y of age in the DRC can help target meaningful interventions. METHOD: Data from the Multiple Indicator Cluster Survey (2001, 2010, 2018) assessed the prevalence of underweight, stunting, and wasting among children under 5. The Slope Index of Inequality (SII) and the Relative Index of Inequality (RII) measured socioeconomic inequalities. We evaluated trends in the entire national sample and stratified subsamples based on place of residence and wealth index quintiles. The final sample included 42 976 children. RESULTS: The national prevalence of underweight and wasting decreased from 31% to 26% and 13% to 6% in rural and urban areas. However, trends in stunting prevalence varied between the two areas. Nutritional disparity widened between low- and high-income families (stunting RIIs: 0.61 in 2001, 0.37 in 2018; stunting SIIs: -0.20 in 2001, -0.40 in 2018; underweight RIIs: 0.53 in 2001, 0.35 in 2018; underweight SIIs: -0.21 in 2001, -0.28 in 2018). Urban areas experienced greater inequality than rural areas (stunting in urban RIIs: 0.41 in 2001, 0.33 in 2010, 0.25 in 2018). CONCLUSION: Despite progress in reducing malnutrition, persistent socioeconomic disparities, particularly in urban areas, remain a serious public health concern in the DRC. Addressing the root causes of malnutrition and ensuring socioeconomically equitable access to nutrition is critical to promote the full potential of children.

Key factors associated with quality of postnatal care: a pooled analysis of 23 countries.

Background: Progress in reducing maternal and neonatal mortality, particularly in low-income and middle-income countries (LMICs) and regions, is insufficient to achieve the Sustainable Developmental Goals by 2030. High-quality postnatal care (PNC) for mothers and neonates is crucial for mothers and babies, yet it remains the most neglected intervention on the continuum of maternal and child care. We aimed to estimate the associations between observable factors and high-quality maternal and neonatal PNC in pooled and country-specific analyses. Methods: In this cross-sectional study, we used the most recent (2015-2022) Demographic and Health Surveys from 23 countries across Africa (n = 14), Southeast Asia (n = 3), Eastern Mediterranean (n = 2), Europe (n = 2), Americas (n = 1), and Western Pacific (n = 1). Women who, within the last 5 years, were aged 15-49 years at their last live birth that had delivered a singleton child were included. We identified eleven PNC behaviours recommended by the World Health Organization (WHO) to measure PNC quality, and applied thresholds to create binary outcomes for quality maternal and neonatal PNC. 15 factors were included in our analysis to assess their association with high-quality PNC for mothers and neonates in a series of single-adjusted and mutually adjusted logistic regression models, both in pooled and country-specific analysis. We also conducted two sets of subgroup analyses for place of residence and maternal age at last birth, and two sets of supplementary analyses to test the robustness of the results. Findings: Among 172,526 women and their most recent child, 41.42% (40.93-41.91) received quality maternal PNC while 42.34% (41.86-42.83) received quality neonatal PNC. In the pooled analysis, we found that the factors showing the strongest associations with quality maternal PNC were delivery by skilled birth attendants (SBAs) (OR: 4.92; 95% CI: 4.32-5.59), four or more antenatal care (ANC) visits (OR: 1.69, 1.58-1.81), and institutional delivery (OR: 1.61; 1.46-1.78). Consistent results were found for all factors of quality newborn care (e.g., delivery by SBA: OR, 4.25; 3.75-4.81; four or more ANC visits: OR, 1.83; 1.70-1.96) except institutional delivery. The association between these leading factors and PNC quality were broadly consistent across countries. Subgroup analyses and sensitivity analyses showed generally consistent results. Interpretation: Our study demonstrated that institutional delivery and frequent ANC visits had the strongest positive associations with quality PNC for both mothers and neonates. Our findings highlight that improvements to the quality of maternal and neonatal PNC in the LMICs we assessed are urgently needed to achieve ambitious maternal, newborn, and child health goals. Funding: China National Natural Science Foundation.

Gelatin Zymography Can Be Performed on Fixed Brain Tissue.

Gelatin zymography is widely used to detect gelatinase activity, which is performed on unfixed tissue because it is assumed that fixation inactivates enzymes. However, using fixed tissues has several advantages over using fresh tissues for such prevention of tissue decay, thereby preserving the proteins as well as the morphology and structure of the specimens. In this study, we investigated the effects of the four commonly used fixatives (ethanol, acetone, zinc-based fixative (ZBF), and paraformaldehyde (PFA)) on the gelatinolytic activity in mouse brain tissue. Multiple protocols were employed to extract proteins from the fixed brain tissue. Western blotting and in-gel zymography (IGZ) were used to detect the gelatinase proteins and gelatinolytic activity of the extractions, respectively. In situ zymography (ISZ) revealed that ethanol, acetone, ZBF, and short-time PFA fixation did not inhibit gelatinolytic activity. Neither 1% Triton + 1 M NaCl nor 10% DMSO + 1 M NaCl was effective in extracting proteins from ethanol-, acetone-, ZBF-, or PFA-fixed brain tissues. However, 8 M urea + 4% CHAPS effectively extracted gelatinase proteins from ethanol- and acetone-fixed tissues while retaining the gelatinolytic activity. 2% SDS effectively extracted gelatinase proteins from ethanol-, acetone-, and ZBF-fixed tissues while retaining the gelatinolytic activity. Although 2% SDS + heating extracted gelatinase proteins from ethanol-, acetone-, ZBF-, and even long-term PFA-fixed tissues, the gelatinolytic activity was not retained. Our findings suggest that both ISZ and IGZ can be performed on fixed brain tissue, which is anticipated to be an improvement over the conventionally used gelatin zymography methods. (J Histochem Cytochem 71: 481-493, 2023).

Promotion of NAD+ recycling by the hypoxia-induced shift in the lactate dehydrogenase isozyme profile reduces the senescence of human bone marrow-derived endothelial progenitor cells.

Expansion of bone marrow-derived endothelial progenitor cells (EPCs) in vitro to obtain required cell numbers for therapeutic applications faces the challenge of growing cell senescence under the traditional normoxic culture condition. We previously found that 1% O2 hypoxic culture condition is favorable for reducing senescence of EPCs, but the mechanisms underlying the favorability are still unclear. Here, we found that, compared with normoxia, hypoxia induced a shift in lactate dehydrogenase (LDH) isozyme profile, which manifested as decreased LDH2 and LDH1 and increased LDH5, LDH4 and total LDHs. Moreover, under hypoxia, EPCs presented higher LDH activity, which could promote the conversion of pyruvate to lactate, as well as a higher level of NAD+, Bcl2 interacting protein 3 (BNIP3) expression and mitophagy. Additionally, under hypoxia, knock-down of the LDHA subunit increased the LDH2 and LDH1 levels and knock-down of the LDHB subunit increased the LDH5 level, while the simultaneous knock-down of LDHA and LDHB reduced total LDHs and NAD+ level. Inhibition of NAD+ recycling reduced BNIP3 expression and mitophagy and promoted cell senescence. Taken together, these data demonstrated that 1% O2 hypoxia induces a shift in the LDH isozyme profile, promotes NAD+ recycling, increases BNIP3 expression and mitophagy, and reduces EPC senescence. Our findings contribute to a better understanding of the connection between hypoxic culture conditions and the senescence of bone marrow-derived EPCs and provide a novel strategy to improve in vitro expansion of EPCs.

Roles of sex hormones in mediating the causal effect of vitamin D on osteoporosis: A two-step Mendelian randomization study.

Background: Although 25-hydroxyvitamin D [25(OH)D] is a risk factor for osteoporosis, it is not clear whether sex hormones mediate this casual association. We aimed to explore how sex hormones affect the association between 25(OH)D and osteoporosis to provide meaningful insights on the underlying mechanisms from a genetic perspective. Methods: Genetic variations in 25(OH)D, total testosterone (TT), androstenedione (A4), estradiol (E2), and testosterone/17ß-estradiol (T/E2) were determined through summary statistics. Taking osteoporosis as the outcome (FinnGen biobank, 332,020 samples), we conducted a Mendelian randomization (MR) analysis to establish the association between 25(OH)D and these sex hormones. The two-step MR analysis quantified the mediatory effects of sex hormones on osteoporosis. The results were further verified by pleiotropy and heterogeneity analyses. Results: MR results showed that 25(OH)D (OR= 1.27, p = 0.04) and TT (OR= 1.25, p = 0.04) had a causal effect on osteoporosis. No significant associations were observed between the other sex hormones (A4, E2, and T/E2) and osteoporosis (p>0.05). Sensitivity analysis (p>0.05) confirmed the robustness of the MR results. The two-step MR analysis provided evidence that the mediatory effect of TT was 0.014 (the percentage of TT mediation was 5.91%). Moreover, the direct effect of 25(OH)D on osteoporosis was 0.221. A4, E2, and T/E2 were not considered as potential mediators of the role of 25(OH)D as a risk factor for OP. Conclusion: This study, through MR analysis, showed that TT mediates the causal effect of 25(OH)D on osteoporosis. Interventions targeting TT, therefore, have the potential to substantially reduce the burden of osteoporosis attributable to high 25(OH)D.

How enlightened self-interest guided global vaccine sharing benefits all: A modeling study.

Background: Despite consensus that vaccines play an important role in combatting the global spread of infectious diseases, vaccine inequity is still a prevalent issue due to a deep-seated mentality of self-priority. We aimed to evaluate the existence and possible outcomes of a more equitable global vaccine distribution and explore a concrete incentive mechanism that promotes vaccine equity. Methods: We designed a metapopulation epidemiological model that simultaneously considers global vaccine distribution and human mobility, which we then calibrated by the number of infections and real-world vaccination records during the coronavirus disease 2019 (COVID-19) pandemic from March 2020 to July 2021. We explored the possibility of the enlightened self-interest incentive mechanism, which comprises improving one's own epidemic outcomes by sharing vaccines with other countries, by evaluating the number of infections and deaths under various vaccine sharing strategies using the proposed model. To understand how these strategies affect the national interests, we distinguished imported from local cases for further cost-benefit analyses that rationalise the enlightened self-interest incentive mechanism behind vaccine sharing. Results: The proposed model accurately reproduces the real-world cumulative infections for both global and regional epidemics (R2>0.990), which can support the following evaluations of different vaccine sharing strategies: High-income countries can reduce 16.7 (95% confidence interval (CI) = 8.4-24.9, P < 0.001) million infection cases and 82.0 (95% CI = 76.6-87.4, P < 0.001) thousand deaths on average by more actively sharing vaccines in an enlightened self-interest manner, where the reduced internationally imported cases outweigh the threat from increased local infections. Such vaccine sharing strategies can also reduce 4.3 (95% CI = 1.2-7.5, P < 0.01) million infections and 7.0 (95% CI = 5.7-8.3, P < 0.001) thousand deaths in middle- and low-income countries, effectively benefiting the whole global population. Lastly, the more equitable vaccine distribution could help largely reduce the global mobility reduction needed for pandemic control. Conclusions: The incentive mechanism of enlightened self-interest we explored here could motivate vaccine equity by realigning the national interest to more equitable vaccine distributions. The positive results could promote multilateral collaborations in global vaccine redistribution and reconcile conflicted national interests, which could in turn benefit the global population.