Albumin-associated free fatty acids induce macropinocytosis in podocytes

Podocytes are specialized epithelial cells in the kidney glomerulus that play important structural and functional roles in maintaining the filtration barrier. Nephrotic syndrome results from a breakdown of the kidney filtration barrier and is associated with proteinuria, hyperlipidemia, and edema. Additionally, podocytes undergo changes in morphology and internalize plasma proteins in response to this disorder. Here, we used fluid-phase tracers in murine models and determined that podocytes actively internalize fluid from the plasma and that the rate of internalization is increased when the filtration barrier is disrupted. In cultured podocytes, the presence of free fatty acids (FFAs) associated with serum albumin stimulated macropinocytosis through a pathway that involves FFA receptors, the Gβ/Gγ complex, and RAC1. Moreover, mice with elevated levels of plasma FFAs as the result of a high-fat diet were more susceptible to Adriamycin-induced proteinuria than were animals on standard chow. Together, these results support a model in which podocytes sense the disruption of the filtration barrier via FFAs bound to albumin and respond by enhancing fluid-phase uptake. The response to FFAs may function in the development of nephrotic syndrome by amplifying the effects of proteinuria

Nuclear Factor κB–dependent Gene Expression Profiling of Hodgkin's Disease Tumor Cells, Pathogenetic Significance, and Link to Constitutive Signal Transducer and Activator of Transcription 5a Activity

Constitutive nuclear nuclear factor (NF)-κB activity is observed in a variety of hematopoietic and solid tumors. Given the distinctive role of constitutive NF-κB for Hodgkin and Reed-Sternberg (HRS) cell viability, we performed molecular profiling in two Hodgkin's disease (HD) cell lines to identify NF-κB target genes. We recognized 45 genes whose expression in both cell lines was regulated by NF-κB. The NF-κB–dependent gene profile comprises chemokines, cytokines, receptors, apoptotic regulators, intracellular signaling molecules, and transcription factors, the majority of which maintain a marker-like expression in HRS cells. Remarkably, we found 17 novel NF-κB target genes. Using chromatin immunoprecipitation we demonstrate that NF-κB is recruited directly to the promoters of several target genes, including signal transducer and activator of transcription (STAT)5a, interleukin-13, and CC chemokine receptor 7. Intriguingly, NF-κB positively regulates STAT5a expression and signaling pathways in HRS cells, and promotes its persistent activation. In fact, STAT5a overexpression was found in most tumor cells of tested patients with classical HD, indicating a critical role for HD. The gene profile underscores a central role of NF-κB in the pathogenesis of HD and potentially of other tumors with constitutive NF-κB activation

Mitochondria DNA mutations cause sex-dependent development of hypertension and alterations in cardiovascular function

Aging is associated with conduit artery stiffening that is a risk factor for and can precede hypertension and ventricular dysfunction. Increases in mitochondria DNA (mtDNA) frequency have been correlated with aging. Mice with a mutation in the encoding domain (D257A) of a proof-reading deficient version of mtDNA polymerase-γ (POLG) have musculoskeletal features of premature aging and a shortened lifespan. However, few studies using these mice have investigated the effects of mtDNA mutations on cardiovascular function. We hypothesized that the proof-reading deficient mtDNA POLG leads to arterial stiffening, hypertension, and ventricular hypertrophy. Ten to twelve month-old D257A mice (n=13) and age- and sex-matched wild-type controls (n=13) were catheterized for hemodynamic and ventricular function measurements. Left common carotid arteries (LCCA) were harvested for mechanical tests followed by histology. Male D257A mice had pulmonary and systemic hypertension, arterial stiffening, larger LCCA diameter (701±45 vs. 597±60 μm), shorter LCCA axial length (8.96±0.56 vs. 10.10±0.80 mm), and reduced hematocrit (29.1±6.1 vs. 41.3±8.1; all p<0.05). Male and female D257A mice had biventricular hypertrophy (p<0.05). Female D257A mice did not have significant increases in pressure or arterial stiffening, suggesting that the mechanisms of hypertension or arterial stiffening from mtDNA mutations differ based on sex. Our results lend insight into the mechanisms of age-related cardiovascular disease and may point to novel treatment strategies to address cardiovascular mortality in the elderly

Increased pore size of scaffolds improves coating efficiency with sulfated hyaluronan and mineralization capacity of osteoblasts

Background: Delayed bone regeneration of fractures in osteoporosis patients or of critical-size bone defects after tumor resection are a major medical and socio-economic challenge. Therefore, the development of more effective and osteoinductive biomaterials is crucial. Methods: We examined the osteogenic potential of macroporous scaffolds with varying pore sizes after biofunctionalization with a collagen/high-sulfated hyaluronan (sHA3) coating in vitro. The three-dimensional scaffolds were made up from a biodegradable three-armed lactic acid-based macromer (TriLA) by cross-polymerization. Templating with solid lipid particles that melt during fabrication generates a continuous pore network. Human mesenchymal stem cells (hMSC) cultivated on the functionalized scaffolds in vitro were investigated for cell viability, production of alkaline phosphatase (ALP) and bone matrix formation. Statistical analysis was performed using student's t-test or two-way ANOVA. Results: We succeeded in generating scaffolds that feature a significantly higher average pore size and a broader distribution of individual pore sizes (HiPo) by modifying composition and relative amount of lipid particles, macromer concentration and temperature for cross-polymerization during scaffold fabrication. Overall porosity was retained, while the scaffolds showed a 25% decrease in compressive modulus compared to the initial TriLA scaffolds with a lower pore size (LoPo). These HiPo scaffolds were more readily coated as shown by higher amounts of immobilized collagen (+ 44%) and sHA3 (+ 25%) compared to LoPo scaffolds. In vitro, culture of hMSCs on collagen and/or sHA3-coated HiPo scaffolds demonstrated unaltered cell viability. Furthermore, the production of ALP, an early marker of osteogenesis (+ 3-fold), and formation of new bone matrix (+ 2.5-fold) was enhanced by the functionalization with sHA3 of both scaffold types. Nevertheless, effects were more pronounced on HiPo scaffolds about 112%. Conclusion: In summary, we showed that the improvement of scaffold pore sizes enhanced the coating efficiency with collagen and sHA3, which had a significant positive effect on bone formation markers, underlining the promise of using this material approach for in vivo studies. © 2019 The Author(s)

Features of teaching Russian as a foreign language on the basis of local history texts

The paper deals with topical issues of teaching Russian as a foreign language (RAFL) and the peculiarities of teaching, taking into account the Linguistic-cultural component. Linguistic-cultural component is considered as materials on regional studies, local history, history, culture and the basics of legislation. Mastering this material will allow students of RAFL courses to master a wide range of background knowledge about the country, traditions, etc. A typology of textbooks on RAFL is given. The most frequently used textbooks on RAFL are examined from the point of view of the material containing a linguistic-cultural component and features that must be taken into account when working with local history material

Multimodal epigenetic changes and altered NEUROD1 chromatin binding in the mouse hippocampus underlie FOXG1 syndrome

Forkhead box G1 (FOXG1) has important functions in neuronal differentiation and balances excitatory/inhibitory network activity. Thus far, molecular processes underlying FOXG1 function are largely unexplored. Here, we present a multiomics data set exploring how FOXG1 impacts neuronal maturation at the chromatin level in the mouse hippocampus. At a genome-wide level, FOXG1 i) both represses and activates transcription, ii) binds mainly to enhancer regions, iii) reconfigures the epigenetic landscape through bidirectional alteration of H3K27ac, H3K4me3, and chromatin accessibility, and iv) operates synergistically with NEUROD1. Interestingly, we could not detect a clear hierarchy of FOXG1 and NEUROD1, but instead, provide the evidence that they act in a highly cooperative manner to control neuronal maturation. Genes affected by the chromatin alterations impact synaptogenesis and axonogenesis. Inhibition of histone deacetylases partially rescues transcriptional alterations upon FOXG1 reduction. This integrated multiomics view of changes upon FOXG1 reduction reveals an unprecedented multimodality of FOXG1 functions converging on neuronal maturation. It fuels therapeutic options based on epigenetic drugs to alleviate, at least in part, neuronal dysfunction

Neighborhood Food Access in Early Life and Trajectories of Child Body Mass Index and Obesity

Importance: Limited access to healthy foods, resulting from residence in neighborhoods with low food access, is a public health concern. The contribution of this exposure in early life to child obesity remains uncertain. Objective: To examine associations of neighborhood food access during pregnancy or early childhood with child body mass index (BMI) and obesity risk. Design, Setting, and Participants: Data from cohorts participating in the US nationwide Environmental Influences on Child Health Outcomes consortium between January 1, 1994, and March 31, 2023, were used. Participant inclusion required a geocoded residential address in pregnancy (mean 32.4 gestational weeks) or early childhood (mean 4.3 years) and information on child BMI. Exposures: Residence in low-income, low-food access neighborhoods, defined as low-income neighborhoods where the nearest supermarket is more than 0.5 miles for urban areas or more than 10 miles for rural areas. Main Outcomes and Measures: BMI z score, obesity (age- and sex-specific BMI ≥95th percentile), and severe obesity (age- and sex-specific BMI ≥120% of the 95th percentile) from age 0 to 15 years. Results: Of 28 359 children (55 cohorts; 14 657 [51.7%] male and 13 702 [48.3%] female; 590 [2.2%] American Indian, Alaska Native, Native Hawaiian, or Other Pacific Islander; 1430 [5.4%] Asian; 4034 [15.3%] Black; 17 730 [67.2%] White; and 2592 [9.8%] other [unspecified] or more than 1 race; 5754 [20.9%] Hispanic and 21 838 [79.1%] non-Hispanic) with neighborhood food access data, 23.2% resided in low-income, low-food access neighborhoods in pregnancy and 24.4% in early childhood. After adjusting for individual sociodemographic characteristics, residence in low-income, low-food access (vs non-low-income, low-food access) neighborhoods in pregnancy was associated with higher BMI z scores at ages 5 years (β, 0.07; 95% CI, 0.03-0.11), 10 years (β, 0.11; 95% CI, 0.06-0.17), and 15 years (β, 0.16; 95% CI, 0.07-0.24); higher obesity risk at 5 years (risk ratio [RR], 1.37; 95% CI, 1.21-1.55), 10 years (RR, 1.71; 95% CI, 1.37-2.12), and 15 years (RR, 2.08; 95% CI, 1.53-2.83); and higher severe obesity risk at 5 years (RR, 1.21; 95% CI, 0.95-1.53), 10 years (RR, 1.54; 95% CI, 1.20-1.99), and 15 years (RR, 1.92; 95% CI, 1.32-2.80). Findings were similar for residence in low-income, low-food access neighborhoods in early childhood. These associations were robust to alternative definitions of low income and low food access and additional adjustment for prenatal characteristics associated with child obesity. Conclusions: Residence in low-income, low-food access neighborhoods in early life was associated with higher subsequent child BMI and higher risk of obesity and severe obesity. We encourage future studies to examine whether investments in neighborhood resources to improve food access in early life would prevent child obesity

Low-dose CT for lung cancer screening in a high-risk population (SUMMIT): a prospective, longitudinal cohort study

Background: Low-dose CT screening reduces lung cancer mortality. In advance of planned national lung cancer screening programmes, research is needed to inform policies regarding implementation. We aimed to assess the implementation of low-dose CT for lung cancer screening in a high-risk population and to validate a multicancer early detection blood test.// Methods: In this prospective, longitudinal cohort study, individuals aged 55–77 years recorded as current smokers in their primary care records at any point within the past 20 years were identified from 329 primary care practices in London (UK) and invited for a lung health check via postal letter. Individuals meeting the 2013 United States Preventive Services Taskforce criteria (current or former smokers within the past 15 years with at least 30 pack-year smoking histories) or having a Prostate, Lung, Colorectal and Ovarian 2012 model 6-year risk of 1·3% or greater, and not currently receiving treatment for an active cancer (except adjuvant hormonal therapy), were eligible for the study. These individuals underwent lung cancer screening via non-contrast, thin collimation low-dose CT. In this analysis, we report the results of the baseline round of low-dose CT screening. Key primary endpoints were those associated with examining the performance of a lung cancer screening service. Outcome measures were analysed on a per-participant level using descriptive frequencies. The study was registered with ClinicalTrials.gov, NCT03934866.// Findings: Between April 8, 2019, and May 14, 2021, 12 773 participants were recruited and analysed. 7353 (57·6%) of 12 773 participants were male and 5420 (42·4%) were female, and 10 665 (83·5%) participants were White. 261 (2·0%) of 12 773 participants were diagnosed with lung cancer (including 163 [1·3%] participants with screen-detected lung cancer and 98 [0·8%] with delayed screen-detected lung cancer [ie, after a 3-month or 6-month nodule follow-up CT]) and 276 (2·2%) participants were diagnosed with any intrathoracic malignancy after a positive baseline screen. 207 (79·3%) of 261 individuals with prevalent screen-detected lung cancer were diagnosed at stage I or II and surgical resection was the primary treatment modality in 201 (77·0%) of 261 individuals. Including cases where multiple resections were done in the same participant (eg, for synchronous primaries), 28 (11·6%) of 241 surgical resections were benign, and there was one (0·4%) death within 90 days of surgery. At 12 months, the episode sensitivity of our low-dose CT screening protocol for detecting lung cancer was 97·0% (95% CI 95·0–99·1; 261 of 269 participants). The specificity was 95·2% (94·8–95·6; 11 905 of 12 504 participants), with a false-positive rate of 4·8% (4·4–5·2).// Interpretation: Large-scale lung cancer screening is effective and can be delivered efficiently to an ethnically and socioeconomically diverse population. Funding GRAIL

Exoerythrocytic Plasmodium Parasites Secrete a Cysteine Protease Inhibitor Involved in Sporozoite Invasion and Capable of Blocking Cell Death of Host Hepatocytes

Plasmodium parasites must control cysteine protease activity that is critical for hepatocyte invasion by sporozoites, liver stage development, host cell survival and merozoite liberation. Here we show that exoerythrocytic P. berghei parasites express a potent cysteine protease inhibitor (PbICP, P. berghei inhibitor of cysteine proteases). We provide evidence that it has an important function in sporozoite invasion and is capable of blocking hepatocyte cell death. Pre-incubation with specific anti-PbICP antiserum significantly decreased the ability of sporozoites to infect hepatocytes and expression of PbICP in mammalian cells protects them against peroxide- and camptothecin-induced cell death. PbICP is secreted by sporozoites prior to and after hepatocyte invasion, localizes to the parasitophorous vacuole as well as to the parasite cytoplasm in the schizont stage and is released into the host cell cytoplasm at the end of the liver stage. Like its homolog falstatin/PfICP in P. falciparum, PbICP consists of a classical N-terminal signal peptide, a long N-terminal extension region and a chagasin-like C-terminal domain. In exoerythrocytic parasites, PbICP is posttranslationally processed, leading to liberation of the C-terminal chagasin-like domain. Biochemical analysis has revealed that both full-length PbICP and the truncated C-terminal domain are very potent inhibitors of cathepsin L-like host and parasite cysteine proteases. The results presented in this study suggest that the inhibitor plays an important role in sporozoite invasion of host cells and in parasite survival during liver stage development by inhibiting host cell proteases involved in programmed cell death