The application of quantitative telomerase activity measurement as an important indicator to monitor the cardiomyocyte differentiation process of human induced pluripotent stem cells under defined conditions.

The construction of an in vitro differentiation system for human induced pluripotent stem cells (hiPSCs) has made exciting progress, but it is still of great significance to clarify the differentiation process. The use of conventional genetic and protein-labeled microscopes to observe or detect different stages of hiPSC differentiation is not specific enough and is cumbersome and time-consuming. In this study, in addition to analyzing the expression of gene/protein-related markers, we used a previously reported simple and excellent quantitative method of cellular telomerase activity based on a quartz crystal microbalance (TREAQ) device to monitor the dynamic changes in cellular telomerase activity in hiPSCs during myocardial differentiation under chemically defined conditions. Finally, by integrating these results, we analyzed the relationship between telomerase activity and the expression of marker genes/proteins as well as the cell type at each study time point. This dynamic quantitative measurement of cellular telomerase activity should be a promising indicator for monitoring dynamic changes in a stage of hiPSC differentiation and inducing cell types. This study provided a quantitative, dynamic and simple monitoring index for the in vitro differentiation process of hiPSC-CMs, which was a certain reference value for the optimization and improvement of the induction system.

Separation and identification of degradation impurities of esomeprazole sodium.

Drug impurities are important factors that affect drug safety and efficacy. The aim of this study is to separate and confirm the structure of two degradation impurities of esomeprazole sodium, designated X and Y. The impurities X and Y were successfully isolated using preparative HPLC by developing separation methods with the help of ACD/Labs AutoChrom software. There was a steady increase in X and Y impurities in forced esomeprazole sodium degradation. Impurity X was confirmed as 6-methoxy-1h-benzo[d]imidazole-2-yl-4-amino-3,5-dimethylpyridinecarboxylate and impurity Y as 6-methoxy-1h-benzo[d]imidazole-2-yl-4-hydroxy-3,5-dimethylpyridinecarboxylate using nuclear magnetic resonance spectrometry, infrared spectroscopy, and high-resolution mass spectrometry. These findings provide a comprehensive understanding of the impurity profile of esomeprazole sodium because these impurities are reported for the first time. Based on our results, active pharmaceutical ingredient manufacturers can further control process parameters to reduce impurity generation, and drug production manufacturers can optimize the packaging and storage conditions of esomeprazole sodium.

[Clinical phenotype and genetic analysis of a child with 3p26.3p25.3 deletion].

OBJECTIVE: To explore the genetic basis for a child with facial dysmorphism and multiple malformations. METHODS: The child, born at 34+6 weeks' gestation due to premature rupture of amniotic membrane, dichorionic diamniotic twinning and gestational diabetes, was subjected to chromosomal karyotyping analysis and copy number variations sequencing (CNV-seq). RESULTS: The child was found to have facial dysmorphism, hypospadia, cryptorchidism and hypotonia. He was found to have a 46,XY,del(3)(p26) karyotype in addition with a 9.80 Mb deletion (chr3: 60 000-9 860 000) encompassing 33 protein coding genes. CONCLUSION: The 3p26.3p25.3 deletion probably underlay the multiple malformations in this child. Continuous follow-up is required to improve his quality of life.

[Genetic analysis of a Chinese pedigree with 6q26q27 microduplication and 15q26.3 microdeletion].

OBJECTIVE: To explore the genetic basis for a Chinese pedigree with 6q26q27 microduplication and 15q26.3 microdeletion. METHODS: A fetus with a 6q26q27 microduplication and a 15q26.3 microdeletion diagnosed at the First Affiliated Hospital of Wenzhou Medical University in January 2021 and members of its pedigree were selected as the study subject. Clinical data of the fetus was collected. The fetus and its parents were analyzed by G-banding karyotyping and chromosomal microarray analysis (CMA), and its maternal grandparents were also subjected to G-banding karyotype analysis. RESULTS: Prenatal ultrasound had indicated intrauterine growth retardation of the fetus, though no karyotypic abnormality was found with the amniotic fluid sample and blood samples from its pedigree members. CMA revealed that the fetus has carried a 6.6 Mb microduplication in 6q26q27 and a 1.9 Mb microdeletion in 15q26.3, and his mother also carried a 6.49 duplication and a 1.867 deletion in the same region. No anomaly was found with its father. CONCLUSION: The 6q26q27 microduplication and 15q26.3 microdeletion probably underlay the intrauterine growth retardation in this fetus.

A Machine Learning Approach to Identify Predictors of Frequent Vaping and Vulnerable Californian Youth Subgroups.

INTRODUCTION: Machine learning presents a unique opportunity to improve electronic cigarette (vaping) monitoring in youth. Here we built a random forest model to predict frequent vaping status among Californian youth and to identify contributing factors and vulnerable populations. METHODS: In this prospective cohort study, 1281 ever-vaping twelfth-grade students from metropolitan Los Angeles were surveyed in Fall and in 6-month in Spring. Frequent vaping was measured at the 6-month follow-up as nicotine-containing vaping on 20 or more days in past 30 days. Predictors (n = 131) encompassed sociodemographic characteristics, substance use and perceptions, health status, and characteristics of the household, school, and neighborhood. A random forest was developed to identify the top ten predictors of frequent vaping and interactions by sociodemographic variables. RESULTS: Forty participants (3.1%) reported frequent vaping at the follow-up. The random forest outperformed a logistic regression model in prediction (C-Index = 0.87 vs. 0.77). Higher past-month nicotine concentration in vape, more daily vaping sessions, and greater nicotine dependence were the top three of the ten most important predictors of frequent vaping. Interactions were found between age and perceived discrimination, and between age and race/ethnicity, as those who were younger than their classmates and either reported experiencing discrimination frequently or identified as Asian or Native American/Pacific Islander were at increased risk of becoming frequent vapers. CONCLUSIONS: Machine learning can produce models that accurately predict progression of vaping behaviors among youth. The potential association between frequent vaping and perceived discrimination warrants more in-depth analyses to confirm if discrimination constitutes a cause of increased vaping. IMPLICATIONS: This study demonstrates the utility of machine learning in predicting status of frequent vaping over 6 months and understanding predictors and nuanced intersectionality by sociodemographic attributes. The high performance of the random forest model has practical implications for a personalized risk calculator that supports vaping prevention program. Public health officials need to recognize the importance of social factors that contribute to frequent vaping, particularly perceived discrimination. Youth subpopulations, including younger high school students and Asians or Native Americans/Pacific Islanders, might require specially designed interventions to help prevent habit-forming in vaping.

Heterozygous pathogenic variants in CWF19L1 in a Chinese family with spinocerebellar ataxia, autosomal recessive 17.

BACKGROUND: CWF19L1 is responsible for spinocerebellar ataxia, autosomal recessive 17, which presents with cerebellar ataxia, and atrophy. Here, we report novel compound heterozygous variants of CWF19L1 in a Chinese family with progressive ataxia and mental retardation of unknown etiology by analyzing clinical characteristics and genetic variations. METHODS: Clinical profiles and genomic DNA extracts of family members were collected. Whole-exome and Sanger sequencing were performed to detect associated genetic variants. Pathogenicity prediction and conservation analysis of the identified variants were performed using bioinformatics tools. RESULTS: We identified heterozygous variants at the invariant +2 position (c.1555_c.1557delGAG in exon 14 and c.1070G > T in exon 11) of the CWF19L1 gene. Two novel heterozygous variants of the CWF19L1 gene were identified in the CWF19L1 gene associated with autosomal recessive cerebellar ataxia. CONCLUSION: Our results suggest that CWF19L1 variants may be a novel cause of recessive ataxia with developmental delay. Whole-exome sequencing is an efficient tool for screening variants associated with the disease. This case report may help diagnose and identify the causes of other ataxias, leading to novel therapies, especially in China. This finding enriches the variant spectrum of the CWF19L1 gene and lays the foundation for future studies on the correlation between genotype and phenotype.

A novel chromosome 2q24.3-q32.1 microdeletion in a fetus with multiple malformations.

BACKGROUND: Terminal or interstitial deletion of chromosome 2q is rarely reported but clinically significant, which can result in developmental malformations and psychomotor retardation in humans. In the present study, we analyzed this deletion to comprehensively clarify the relationship between phenotype and microdeletion region. METHODS: We collected clinical records of the fetus and summarized patient symptoms. Subsequently, genomic DNA was extracted from fetal tissue or peripheral blood collected from parents. In addition, whole-exome sequencing (WES) and copy number variation sequencing (CNV-seq) were performed. RESULTS: The fetus presented a previously unreported interstitial deletion of 2q24.3-q32.1. WES and CNV-seq revealed a de novo 18.46 Mb deletion at 2q24.3-q32.1, a region involving 94 protein-coding genes, including HOXD13, MAP3K20, DLX1, DLX2, SCN2A, and SCN1A. The fetus had upper and lower limb malformations, including camptodactyly and syndactyly, along with congenital cardiac defects. CONCLUSION: Herein, we report a fetus with a novel microdeletion of chromosome 2q24.3-q32.1, likely a heterozygous pathogenic variant. Haploinsufficiency of HOXD13 might be related to limb deformity in the fetus.

[Analysis of phenotype and genetic variant in a family with Shprintzen-Goldberg syndrome].

OBJECTIVE: To explore the genetic basis for a proband with Shprintzen-Goldberg syndrome (SGS). METHODS: Whole exome sequencing was carried out to detect potential variants associated with the relevant phenotypes. Candidate variants were verified by Sanger sequencing of the patient and her family. RESULTS: DNA sequencing revealed that that the proband has carried a de novo heterozygous missense c.94C>G (p.Leu32Val) variant in exon 1 of the SKI gene (NM_003036), which has been reported previously. The same variant was not detected in either parent. Based on the guidelines of the American College of Medical Genetics and Genomics, the variant was predicted to be pathogenic (PS1+PS2+PM1+PM2+PP2+PP3). CONCLUSION: The SKI c.94C>G (p. Leu32Val) variant probably underlay the autosomal dominant SGS in this patient.

[Analysis of PROC gene variant in a Chinese pedigree affected with hereditary protein C deficiency].

OBJECTIVE: To explore the molecular pathogenesis of a Chinese pedigree affected with inherited protein C (PC) deficiency. METHODS: The protein C activity (PC:A) and protein C antigen (PC:Ag) of the proband and his family members were determined by a chromogenic substrate method and enzyme-linked immunosorbent assay, respectively. The proband was subjected to whole exome sequencing. Candidate variants were verified by Sanger sequencing of other members of the pedigree. RESULTS: The PC:A and PC:Ag of proband were reduced to 15% and 11%, respectively. The above parameters of his parents and elder sister were also decreased to approximately 50% of reference values. Next generation sequencing has revealed that the proband has harbored a heterozygous c.572_574delAGA (p.Glu191_Lys192delinsGlu) variant in exon 7 and a missense c.752C>T (p.Ala251Val) variant in exon 8 of the PROC gene. His father was heterozygous for the c.572_574delAGA variant, while his mother and elder sister were heterozygous for the c.752C>T variant. According to the American College of Medical Genetics and Genomics Standards and Guidelines, the c.572_574delAGA (p.Glu191_Lys192 delinsGlu) variant was predicted to be likely pathogenic (PS1+PM4+PP3). c.752 C>T (p.Ala251Val) variant was also likely pathogenic (PS1+PM1+PP3). CONCLUSION: The deletional variant of c.572_574delAGA (p.Glu191_Lys192delinsGlu) in exon 7 and missense variant c.752C>T (p.Ala251Val) in exon 8 of the PROC gene probably underlay the inherited protein C (PC) deficiency in this pedigree. Above finding has enriched the spectrum of PROC gene variants and provided a basis for genetic counseling for this pedigree.

Homocysteine aggravates DNA damage by impairing the FA/Brca1 Pathway in NE4C murine neural stem cells.

There is existing evidence that elevated homocysteine (Hcy) levels are risk factors for some neurodegenerative disorders. The pathogenesis of neurological diseases could be contributed to excessive cell dysfunction and death caused by defective DNA damage response (DDR) and accumulated DNA damage. Hcy is a neurotoxic amino acid and acts as a DNA damage inducer. However, it is not clear whether Hcy participates in the DDR. To investigate the effects of Hcy on DNA damage and the DDR, we employed mitomycin C (MMC) to cause DNA damage in NE4C murine neural stem cells (NSCs). Compared to treatment with MMC alone, we found that co-treatment with MMC and Hcy worsened DNA damage and increased death in NE4C cells. Intriguingly, in this DNA damage model mimicked by MMC, immunoblotting results showed that the monoubiquitination levels of Fanconi anemia complementation group I (Fanci) and Fanconi anemia complementation group D2 (Fancd2) were decreased to about 60.3% and 55.7% by supplementing cell culture medium with Hcy, indicating Hcy inactivates the function of Fanci and Fancd2 in DNA damage conditions. Given Breast Cancer 1 (BRCA1) is an important downstream of FANCD2, we next detected the interaction between Fancd2 and Brca1 in NE4C cells. Compared to treatment with MMC alone, the Fancd2-Brca1 interaction and the amount of Brca1 on chromatin were decreased when cells were co-exposed to MMC and Hcy, suggesting Hcy could impair the Fanconi anemia (FA)/Brca1 pathway. Taken together, our study demonstrates that Hcy may enhance cell death, which contributes to the accumulation of DNA damage and promotion of hypersensitivity to cytotoxicity by impairing the FA/Brca1 pathway in murine NSCs in the presence of DNA damage.

Investigation of the optimal suspension culture time for the osteoblastic differentiation of human induced pluripotent stem cells using the embryoid body method.

The differentiation of human induced pluripotent stem cells (hiPSCs) into osteoblasts provides a new paradigm in the field of bone tissue regeneration. The embryoid body (EB) differentiation method is commonly used for the osteogenic differentiation of hiPSCs. However, the spontaneous differentiation process of EBs is poorly understood, as evidenced by the inconsistency of the suspension time among previously reported studies as well as the low osteoblastic differentiation efficiency of hiPSCs. In the present study, we investigated the effects of the suspension culture time of EBs on the osteogenic differentiation of hiPSCs. Under chemically defined conditions, the expression of key genes related to presomitic mesoderm, neural crest, mesenchymal and pre-osteoblast cells in EBs derived from hiPSCs was examined daily by quantitative RT-PCR. Then, EBs with varying times in suspension (3, 5, 7 or 10 days) were attached onto gelatine surfaces, and their osteoblastic differentiation efficiencies after 14 days of culture in osteogenic induction medium were determined. Our results showed that EBs derived from hiPSCs subjected to 4 days of suspension culture produced the most mesenchymal stem cells, and exhibited the best osteogenic differentiation efficiency. Our research is valuable to standardizing, the time in suspension for the osteogenic differentiation of hiPSCs through the EB method, and facilitated the development of a high-efficiency in vitro osteogenic differentiation system for hiPSCs.

Detection of lung cancer through SERS analysis of serum.

Early detection and postoperative assessment are crucial for improving overall survival among lung cancer patients. Here, we report a non-invasive technique that integrates Raman spectroscopy with machine learning for the detection of lung cancer. The study encompassed 88 postoperative lung cancer patients, 73 non-surgical lung cancer patients, and 68 healthy subjects. The primary aim was to explore variations in serum metabolism across these cohorts. Comparative analysis of average Raman spectra was conducted, while principal component analysis was employed for data visualization. Subsequently, the augmented dataset was used to train convolutional neural networks (CNN) and Resnet models, leading to the development of a diagnostic framework. The CNN model exhibited superior performance, as verified by the receiver operating characteristic curve. Notably, postoperative patients demonstrated an increased likelihood of recurrence, emphasizing the crucial need for continuous postoperative monitoring. In summary, the integration of Raman spectroscopy with CNN-based classification shows potential for early detection and postoperative assessment of lung cancer.

Define of Optimal Addition Period of Osteogenic Peptide to Accelerate the Osteogenic Differentiation of Human Pluripotent Stem Cells.

BACKGROUND: The addition of growth factiors is commonly applied to improve the osteogenic differentiation of stem cells. However, for human pluripotent stem cells (hPSCs), their complex differentiation processes result in the unknown effect at different stages. In this study, we focused on the widely used bone forming peptide-1 (BFP-1) and investigated the effect and mechanisms of its addition on the osteogenic induction of hPSCs as a function of the supplementation period. METHODS: Monolayer-cultured hPSCs were cultured in osteogenic induction medium for 28 days, and the effect of BFP-1 peptide addition at varying weeks was examined. After differentiation for varying days (0, 7, 14, 21 and 28), the differentiation efficiency was determined by RT-PCR, flow cytometry, immunofluorescence, and alizarin red staining assays. Moreover, the expression of marker genes related to germ layers and epithelial-mesenchymal transition (EMT) was investigated at day 7. RESULTS: Peptide treatment during the first week promoted the generation of mesoderm cells and mesenchymal-like cells from hiPSCs. Then, the upregulated expression of osteogenesis marker genes/proteins was detected in both hESCs and hiPSCs during subsequent inductions with BFP-1 peptide treatment. Fortunately, further experimental design confirmed that treating the BFP-1 peptide during 7-21 days showed even better performance for hESCs but was ineffective for hiPSCs. CONCLUSION: The differentiation efficiency of cells could be improved by determining the optimal treatment period. Our study has great value in maximizing the differentiation of hPSCs by adding osteogenesis peptides based on the revealed mechanisms and promoting the application of hPSCs in bone tissue regeneration.

Relapsing polychondritis-associated meningoencephalitis initially presenting as seizure: a case report and literature review.

Background and purpose: Relapsing polychondritis (RP) is a rare rheumatologic disorder that may affect the neurological system with various presentations. In this study, we present a case and summarize the clinical characteristics of RP-associated meningoencephalitis. Case presentation: A 48-year-old man presented with first-ever seizures that were well controlled by valproate. Physical examination results were unremarkable, except for binaural deformation. The initial brain magnetic resonance imaging (MRI) without contrast and electroencephalogram (EEG) findings were normal. However, the patient subsequently developed recurrent fever, scleritis, headache, lethargy, and left arm paresis. Repeated brain MRI with contrast demonstrated increased enhancement of the pia mater and abnormal diffusion-weighted imaging (DWI) signals in the bilateral auricles. The cerebrospinal fluid (CSF) analysis showed 2 leukocytes/µL, 736.5 mg/L of protein, and no evidence of infectious disease or autoimmune encephalitis. Meningoencephalitis secondary to RP was considered. The patient's condition improved significantly and quickly with the administration of dexamethasone (10 mg per day). Oral methylprednisolone was continued, and the patient remained well without relapse during the 9-month follow-up period. Conclusion: RP-associated meningoencephalitis is rare but fatal. Although symptoms vary, red or deformed ears remain the most common and suggestive features. Non-specific parenchymal changes and/or meningeal enhancement can be observed on brain MRI scans. CSF lymphocytic pleocytosis with mild protein elevation was observed in most patients.

The Role of Macrophage Phenotype in the Vascularization of Prevascularized Human Bone Marrow Mesenchymal Stem Cell Sheets.

With the development of tissue engineering and regenerative medicine, prevascularized bone marrow mesenchymal stem cell (BMSC) sheets have been regarded as a promising method for tissue regeneration. Furthermore, the inflammatory response is one of the main regulators of vascularization and the restoration of engineered tissue function; among them, macrophages and cytokines produced by them are considered to be the decisive factors of the downstream outcomes. This study investigated the effect of macrophages on the formation of microvascular-like structures of human umbilical vein endothelial cells (HUVECs) in BMSC sheets. First, a human monocytic leukemia cell line (THP-1 cells) was differentiated into derived macrophages (M0) with phorbol 12-myristate 13-acetate and further activated into proinflammatory macrophages (M1 macrophages) with interferon-γ and lipopolysaccharide or anti-inflammatory macrophages (M2 macrophages) with interleukin-4. Then, HUVECs and prevascularized sheets were treated with conditioned media (CM) from different macrophages, and the impact of macrophage phenotypes on vascularized network formation in prevascularized cell sheets was examined by hematoxylin and eosin staining, CD31 immunofluorescence staining and enzyme-linked immunosorbent assay. Our study showed that macrophages may guide the arrangement of endothelial cells through a paracrine pathway. Cell sheets that were cultured in the CM from M2 macrophages were thinner than those cultured in other media. At various time points, the levels of tumor necrosis factor alpha and vascular endothelial growth factor in prevascularized sheets cultured with CM(M1) was higher than that in sheets cultured with other media; however, the levels of platelet-derived growth factor in prevascularized sheets cultured with CM(M2) was higher than that in sheets cultured with other media. These findings suggest that the paracrine effect of macrophages can influence the formation of microvascular networks in prevascularized sheets by regulating the arrangement of cells, the thickness of the cell sheet and the secretion of cytokines related to angiogenesis. Macrophages with different phenotypes have unique effects on prevascularized sheets.

Quantification of the apical palatal bone index for maxillary incisor immediate implant assessment: A retrospective cross-sectional study.

BACKGROUND: Apical palatal bone is important in immediate implant evaluation. Current consensus gives qualitative suggestions regarding it, limiting its clinical decision-making value. OBJECTIVES: To quantify the apical palatal bone dimension in maxillary incisors and reveal its quantitative correlation with other implant-related hard tissue indices to give practical advice for pre-immediate implant evaluation and design. MATERIAL AND METHODS: A retrospective analysis of immediate implant-related hard tissue indices in maxillary incisors obtained by cone beam computed tomography (CBCT) was conducted. Palatal bone thickness at the apex level (Apical-P) on the sagittal section was selected as a parameter reflecting the apical palatal bone. Its quantitative correlation with other immediate implant-related hard tissue indices was revealed. Clinical advice of pre-immediate implant assessment was given based on the quantitative classification of Apical-P and its other correlated immediate implant-related hard tissue indices. RESULTS: Apical-P positively correlated with cervical palatal bone, whole cervical buccal-palatal bone, sagittal root angle, and basal bone width indices. while negatively correlated with apical buccal bone, cervical buccal bone, and basal bone length indices. Six quantitative categories of Apical-P are proposed. Cases with Apical-P below 4 mm had an insufficient apical bone thickness to accommodate the implant placement, while Apical-P beyond 12 mm should be cautious about the severe implant inclination. Cases with Apical-P of 4-12 mm can generally achieve satisfying immediate implant outcomes via regulating the implant inclination. CONCLUSIONS: Quantification of the apical palatal bone index for maxillary incisor immediate implant assessment can be achieved, providing a quantitative guide for immediate implant placement in the maxillary incisor zone.

Metabolomics profiling of maternal and umbilical cord blood in normoglycemia macrosomia.

Background: Macrosomia is a common disorder that occurs during pregnancy. We investigated the comprehensive metabolite profiles of pregnant maternal and fetal sera in normoglycemic macrosomia in a Chinese population. Methods: Forty pregnant women and their fetuses were included in the study (twenty macrosomia patients and twenty normal-weight controls). Maternal and umbilical cord serum metabolites were identified using ultra-performance liquid chromatography coupled with tandem mass spectrometry. Results: In total, 203 metabolites were identified. Lipids and lipid-like molecules were the predominant metabolites. Fifty-three metabolites with significant differences were obtained in the maternal samples. In the macrosomia group, the levels of docosahexaenoic acid, eicosapentaenoic acid, and arachidonic acid were significantly higher than those in the control group. Umbilical cord serum samples were obtained for 24 different metabolites. The maternal-fetal gradient of polyunsaturated fatty acids was decreased in the macrosomia group. Aconitic acid, citric acid, isocitric acid, 2-methylhexanoic acid, and 12-hydroxystearic acid were the common differential metabolites in the maternal and umbilical cord serum samples. Conclusion: There were obvious metabolic abnormalities in the sera of pregnant women and fetuses with macrosomia. Lipids and lipid-like molecules were the predominant differential metabolites but had different classifications in the maternal and umbilical cord serum. These results may provide new insights into the long-term metabolic disorders associated with macrosomia.

Improving hard metal implant and soft tissue integration by modulating the "inflammatory-fibrous complex" response.

Soft tissue integration is one major difficulty in the wide applications of metal materials in soft tissue-related areas. The inevitable inflammatory response and subsequent fibrous reaction toward the metal implant is one key response for metal implant-soft tissue integration. It is of great importance to modulate this inflammatory-fibrous response, which is mainly mediated by the multidirectional interaction between fibroblasts and macrophages. In this study, macrophages are induced to generate M1 and M2 macrophage immune microenvironments. Their cytokine profiles have been proven to have potentially multi-regulatory effects on fibroblasts. The multi-reparative effects of soft tissue cells (human gingival fibroblasts) cultured on metal material (titanium alloy disks) in M1 and M2 immune microenvironments are then dissected. Fibroblasts in the M1 immune microenvironment tend to aggravate the inflammatory response in a pro-inflammatory positive feedback loop, while M2 immune microenvironment enhances multiple functions of fibroblasts in soft tissue integration, including soft tissue regeneration, cell adhesion on materials, and contraction to immobilize soft tissue. Enlighted by the close interaction between macrophages and fibroblasts, we propose the concept of an "inflammatory-fibrous complex" to disclose possible methods of precisely and effectively modulating inflammatory and fibrous responses, thus advancing the development of metal soft tissue materials.

A rapidly evolving single copy histone H1 variant is associated with male fertility in a parasitoid wasp.

The linker histone H1 binds to the nucleosome core particle at the site where DNA enters and exits, and facilitates folding of the nucleosomes into a higher-order chromatin structure in eukaryotes. Additionally, some variant H1s promote specialized chromatin functions in cellular processes. Germline-specific H1 variants have been reported in some model species with diverse roles in chromatin structure changes during gametogenesis. In insects, the current understanding of germline-specific H1 variants comes mainly from the studies in Drosophila melanogaster, and the information on this set of genes in other non-model insects remains largely unknown. Here, we identify two H1 variants (PpH1V1 and PpH1V2) that are specifically predominantly expressed in the testis of the parasitoid wasp Pteromalus puparum. Evolutionary analyses suggest that these H1 variant genes evolve rapidly, and are generally maintained as a single copy in Hymenoptera. Disruption of PpH1V1 function in the late larval stage male by RNA interference experiments has no phenotype on spermatogenesis in the pupal testis, but results in abnormal chromatin structure and low sperm fertility in the adult seminal vesicle. In addition, PpH1V2 knockdown has no detectable effect on spermatogenesis or male fertility. Collectively, our discovery indicates distinct functions of male germline-enriched H1 variants between parasitoid wasp Pteromalus and Drosophila, providing new insights into the role of insect H1 variants in gametogenesis. This study also highlights the functional complexity of germline-specific H1s in animals.

A machine learning approach to predict e-cigarette use and dependence among Ontario youth. / Une approche d'apprentissage automatique pour prédire l'utilisation des cigarettes électroniques et la dépendance à celles-ci chez les jeunes de l'Ontario.

INTRODUCTION: We developed separate random forest algorithms to predict e-cigarette (vaping) ever use and daily use among Ontario youth, and subsequently examined predictor importance and statistical interaction. METHODS: This cross-sectional study used a representative sample of Ontario elementary and high school students in 2019 (N = 6471). Vaping frequency over the last 12 months was used to define ever-vaping and daily vaping. We considered a large set of individual characteristics as potential correlates for ever-vaping (176 variables) and daily vaping (179 variables). Using cross-validation, we developed random forest algorithms and evaluated model performance based on the C-index, a measure to assess the discriminatory ability of a model, for both outcomes. Further, the top 10 correlates were identified by relative importance score calculation and their interaction with sociodemographic characteristics. RESULTS: There were 2064 (31.9%) ever-vapers, and 490 (7.6%) of the respondents were daily users. The random forest algorithms for both outcomes achieved high performance, with C-index over 0.90. The top 10 correlates of daily vaping included use of caffeine, cannabis and tobacco, source and type of e-cigarette and absence in last 20 school days. Those of ever-vaping included school size, use of alcohol, cannabis and tobacco; 9 of the top 10 ever-vaping correlates demonstrated interactions with ethnicity. CONCLUSION: Machine learning is a promising methodology for identifying the risks of ever-vaping and daily vaping. Furthermore, it enables the identification of important correlates and the assessment of complex intersections, which may inform future longitudinal studies to customize public health policies for targeted population subgroups.