The Transcriptome and DNA Methylome Landscapes of Human Primordial Germ Cells.

Germ cells are vital for transmitting genetic information from one generation to the next and for maintaining the continuation of species. Here, we analyze the transcriptome of human primordial germ cells (PGCs) from the migrating stage to the gonadal stage at single-cell and single-base resolutions. Human PGCs show unique transcription patterns involving the simultaneous expression of both pluripotency genes and germline-specific genes, with a subset of them displaying developmental-stage-specific features. Furthermore, we analyze the DNA methylome of human PGCs and find global demethylation of their genomes. Approximately 10 to 11 weeks after gestation, the PGCs are nearly devoid of any DNA methylation, with only 7.8% and 6.0% of the median methylation levels in male and female PGCs, respectively. Our work paves the way toward deciphering the complex epigenetic reprogramming of the germline with the aim of restoring totipotency in fertilized oocytes.

Enterovirus 71 Activates Plasmacytoid Dendritic Cell-Dependent PSGL-1 Binding Independent of Productive Infection.

Enterovirus 71 (EV71) is a significant causative agent of hand, foot, and mouth disease, with potential serious neurologic complications or fatal outcomes. The lack of effective treatments for EV71 infection is attributed to its elusive pathogenicity. Our study reveals that human plasmacytoid dendritic cells (pDCs), the main type I IFN-producing cells, selectively express scavenger receptor class B, member 2 (SCARB2) and P-selectin glycoprotein ligand 1 (PSGL-1), crucial cellular receptors for EV71. Some strains of EV71 can replicate within pDCs and stimulate IFN-α production. The activation of pDCs by EV71 is hindered by Abs to PSGL-1 and soluble PSGL-1, whereas Abs to SCARB2 and soluble SCARB2 have a less pronounced effect. Our data suggest that only strains binding to PSGL-1, more commonly found in severe cases, can replicate in pDCs and induce IFN-α secretion, highlighting the importance of PSGL-1 in these processes. Furthermore, IFN-α secretion by pDCs can be triggered by EV71 or UV-inactivated EV71 virions, indicating that productive infection is not necessary for pDC activation. These findings provide new insights into the interaction between EV71 and pDCs, suggesting that pDC activation could potentially mitigate the severity of EV71-related diseases.

The mucosal concept in chronic rhinosinusitis: Focus on the epithelial barrier.

Chronic rhinosinusitis (CRS) is a common chronic nasal cavity and sinus disease affecting a growing number of individuals worldwide. Recent advances have shifted our understanding of CRS pathophysiology from a physical obstruction model of ventilation and drainage to a mucosal concept that recognizes the complexities of mucosal immunologic variations and cellular aberrations. A growing number of studies have demonstrated the alteration of the epithelial barrier during inflammatory states. Therefore, the current review has focused on the crucial role of epithelial cells within this mucosal framework in CRS, detailing the perturbed epithelial homeostasis, impaired epithelial cell barrier, dysregulated epithelial cell repair processes, and enhanced interactions between epithelial cells and immune cells. Notably, the utilization of novel technologies, such as single-cell transcriptomics, has revealed the novel functions of epithelial barriers, such as inflammatory memory and neuroendocrine functions. Therefore, this review also emphasizes the importance of epithelial inflammatory memory and the necessity of further investigations into neuroendocrine epithelial cells and neurogenic inflammation in CRS. We conclude by contemplating the prospective benefits of epithelial cell-oriented biological treatments, which are currently under investigation in rigorous randomized, double-blind clinical trials in patients with CRS with nasal polyps.

Integrative Analysis of Lactylome and Proteome of Hypertrophic Scar To Identify Pathways or Proteins Associated with Disease Development.

Lactylation (Kla), a recently discovered post-translational modification derived from lactate, plays crucial roles in various cellular processes. However, the specific influence of lactylation on the biological processes underlying hypertrophic scar formation remains unclear. In this study, we present a comprehensive profiling of the lactylome and proteome in both hypertrophic scars and adjacent normal skin tissues. A total of 1023 Kla sites originating from 338 nonhistone proteins were identified based on lactylome analysis. Proteome analysis in hypertrophic scar and adjacent skin samples revealed the identification of 2008 proteins. It is worth noting that Kla exhibits a preference for genes associated with ribosome function as well as glycolysis/gluconeogenesis in both normal skin and hypertrophic scar tissues. Furthermore, the functional enrichment analysis demonstrated that differentially lactyled proteins are primarily involved in proteoglycans, HIF-1, and AMPK signaling pathways. The combined analysis of the lactylome and proteome data highlighted a significant upregulation of 14 lactylation sites in hypertrophic scar tissues. Overall, our investigation unveiled the significant involvement of protein lactylation in the regulation of ribosome function as well as glycolysis/gluconeogenesis, potentially contributing to the formation of hypertrophic scars.

Metabolic engineering of Candida tropicalis for efficient 1,2,4-butanetriol production.

1,2,4-Butanetriol serves as a precursor in the manufacture of diverse pharmaceuticals and the energetic plasticizer 1,2,4-butanetriol trinitrate. The study involved further modifications to an engineered Candida tropicalis strain, aimed at improving the production efficiency of 1,2,4-butanetriol. Faced with the issue of xylonate accumulation due to the low activity of heterologous xylonate dehydratase, we modulated iron metabolism at the transcriptional level to boost intracellular iron ion availability, thus enhancing the enzyme activity by 2.2-fold. Addressing the NADPH shortfall encountered during 1,2,4-butanetriol biosynthesis, we overexpressed pivotal genes in the NADPH regeneration pathway, achieving a 1,2,4-butanetriol yield of 3.2 g/L. The introduction of calcium carbonate to maintain pH balance led to an increased yield of 4 g/L, marking a 111% improvement over the baseline strain. Finally, the use of corncob hydrolysate as a substrate culminated in 1,2,4-butanetriol production of 3.42 g/L, thereby identifying a novel host for the conversion of corncob hydrolysate to 1,2,4-butanetriol.

Lipidomic signatures in patients with early-onset and late-onset Preeclampsia.

BACKGROUND: Preeclampsia is a pregnancy-specific clinical syndrome and can be subdivided into early-onset preeclampsia (EOPE) and late-onset preeclampsia (LOPE) according to the gestational age of delivery. Patients with preeclampsia have aberrant lipid metabolism. This study aims to compare serum lipid profiles of normal pregnant women with EOPE or LOPE and screening potential biomarkers to diagnose EOPE or LOPE. METHODS: Twenty normal pregnant controls (NC), 19 EOPE, and 19 LOPE were recruited in this study. Untargeted lipidomics based on ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) was used to compare their serum lipid profiles. RESULTS: The lipid metabolism profiles significantly differ among the NC, EOPE, and LOPE. Compared to the NC, there were 256 and 275 distinct lipids in the EOPE and LOPE, respectively. Furthermore, there were 42 different lipids between the LOPE and EOPE, of which eight were significantly associated with fetal birth weight and maternal urine protein. The five lipids that both differed in the EOPE and LOPE were DGTS (16:3/16:3), LPC (20:3), LPC (22:6), LPE (22:6), PC (18:5e/4:0), and a combination of them were a potential biomarker for predicting EOPE or LOPE. The receiver operating characteristic analysis revealed that the diagnostic power of the combination for distinguishing the EOPE from the NC and for distinguishing the LOPE from the NC can reach 1.000 and 0.992, respectively. The association between the lipid modules and clinical characteristics of EOPE and LOPE was investigated by the weighted gene co-expression network analysis (WGCNA). The results demonstrated that the main different metabolism pathway between the EOPE and LOPE was enriched in glycerophospholipid metabolism. CONCLUSIONS: Lipid metabolism disorders may be a potential mechanism of the pathogenesis of preeclampsia. Lipid metabolites have the potential to serve as biomarkers in patients with EOPE or LOPE. Furthermore, lipid metabolites correlate with clinical severity indicators for patients with EOPE and LOPE, including fetal birth weight and maternal urine protein levels.

Near-full-length genome analysis of two novel HIV second recombinant forms in Hebei, China.

The number of individuals infected with HIV-1 among men who have sex with men (MSM) has risen rapidly in recent years in China, and the subtypes CRF01_AE, CRF07_BC, and B, as well as many novel unique recombinant forms (URFs) are prevalent among them. Co-circulation of strains among MSM populations allows the generation of circulating recombinant forms (CRFs) and URFs. In this study, we identified two new URFs from two HIV-1-positive subjects who were infected through homosexual contact in Hebei, China. Analysis of near-full-length genome sequences, using phylogenetic and recombination analysis showed that the two URFs originated from CRF01_AE, CRF07_BC, and B, and CRF01_AE segments in the backbone of the URFs were derived from cluster 4 of CRF01_AE. The CRF07_BC segments of two URFs were clustered with 07BC_N in a phylogenetic tree. The identification of novel URFs with complex genomic structures shows that it is necessary to strengthen surveillance of HIV-1 variants in MSM populations in this region.

Comparison of clinical traits for seasonal and perennial allergic rhinitis during allergen exposure.

Background: Allergic rhinitis (AR) is traditionally subdivided into seasonal AR (SAR) and perennial AR (PAR) according to the type of allergen and the occurrence of symptoms during the year. There are currently no reports on the comparison of trait profiles for SAR and PAR during the allergen exposure. Purpose: The purpose of this study was to analyze the clinical characteristics of SAR and PAR during respective allergen exposure periods to provide valuable information for the development of treatment strategies. Methods: This study was performed between August 1, 2021, and January 31, 2022, in the Department of Allergy, Beijing Tongren Hospital. We continuously included diagnosed SAR and PAR outpatients who volunteered to participate in the survey. A questionnaire with regard to medical history, severity of symptoms, and diagnosis and treatment status was collected. Results: A total of 296 patients with SAR and 448 with PAR were finally recruited. Patients with SAR had more severe rhinorrhea compared with patients with PAR (p < 0.001), whereas there was no statistically significant difference in the severity of itching, sneezing, and congestion between the two entities (p ≥ 0.05). Both the gritty and watery eyes of patients with SAR were noticeably more severe than those of patients with PAR (PTotal Ocular Symptom Score [PTOSS] < 0.001). AR symptom severity is mainly associated with the comorbid allergic conjunctivitis (odds ratio 1.94 [95% confidence interval, 1.21-3.09]). SAR patients and PAR patients show no statistically significant differences in terms of their frequency of visits, annual expenditure, and choice of medication treatment for AR (p > 0.05). The overall control under standard medication of both patients with PAR and those with SAR is not ideal, especially in SAR. Conclusion: The current cross-sectional study demonstrated that the patients with SAR exhibited more severe overall clinical symptoms than those with PAR, especially nasal rhinorrhea and gritty and watery eyes. Both of the two disease entities have poor control under standardized medication treatment, especially in SAR. Further multicenter longitudinal studies that involve larger and more diverse populations should be conducted to provide a more accurate and comprehensive understanding of the condition.

Paternal genetic variants and risk of obstructive heart defects: A parent-of-origin approach.

Previous research on risk factors for obstructive heart defects (OHDs) focused on maternal and infant genetic variants, prenatal environmental exposures, and their potential interaction effects. Less is known about the role of paternal genetic variants or environmental exposures and risk of OHDs. We examined parent-of-origin effects in transmission of alleles in the folate, homocysteine, or transsulfuration pathway genes on OHD occurrence in offspring. We used data on 569 families of liveborn infants with OHDs born between October 1997 and August 2008 from the National Birth Defects Prevention Study to conduct a family-based case-only study. Maternal, paternal, and infant DNA were genotyped using an Illumina Golden Gate custom single nucleotide polymorphism (SNP) panel. Relative risks (RR), 95% confidence interval (CI), and likelihood ratio tests from log-linear models were used to estimate the parent-of-origin effect of 877 SNPs in 60 candidate genes in the folate, homocysteine, and transsulfuration pathways on the risk of OHDs. Bonferroni correction was applied for multiple testing. We identified 3 SNPs in the transsulfuration pathway and 1 SNP in the folate pathway that were statistically significant after Bonferroni correction. Among infants who inherited paternally-derived copies of the G allele for rs6812588 in the RFC1 gene, the G allele for rs1762430 in the MGMT gene, and the A allele for rs9296695 and rs4712023 in the GSTA3 gene, RRs for OHD were 0.11 (95% CI: 0.04, 0.29, P = 9.16x10-7), 0.30 (95% CI: 0.17, 0.53, P = 9.80x10-6), 0.34 (95% CI: 0.20, 0.57, P = 2.28x10-5), and 0.34 (95% CI: 0.20, 0.58, P = 3.77x10-5), respectively, compared to infants who inherited maternally-derived copies of the same alleles. We observed statistically significant decreased risk of OHDs among infants who inherited paternal gene variants involved in folate and transsulfuration pathways.

Genetics and epigenetics of chronic rhinosinusitis.

Discerning the genetics and epigenetics of chronic rhinosinusitis (CRS) may optimize outcomes through early diagnostics, personalized and novel therapeutics, and early prognostication. CRS associated with cystic fibrosis and primary ciliary dyskinesia has well-characterized genetic mutations. Most CRS subjects, however, do not exhibit identifiable monogenic alterations. Clustering in related individuals is seen in CRS with nasal polyps. Spouses of subjects with CRS without nasal polyps also may be at increased risk of the same disease. These observations generate questions on genetic and environmental influences in CRS. Genome-wide association studies have identified variations and polymorphisms between CRS and control subjects in genes related to innate and adaptive immunity. Candidate gene and transcriptomics studies have investigated and identified genetic variations related to immunity, inflammation, epithelial barrier function, stress-response, antigen processing, T-cell regulation, and cytokines in CRS. Epigenetic studies have identified mechanisms through which environmental factors may affect these gene functions. However, causality is not determined for most variations. Inferences drawn from these data must be measured because most investigations report unreplicated results from small study populations. Large, replicated studies in tight cohorts across diverse populations remain a pressing need in studying CRS genetics.

Increased prevalence and stable clustering rate of HIV-1 transmitted drug resistance strains after 'treat-all' in a megacity of China.

OBJECTIVES: The 'treat-all' strategy was implemented in Shenzhen, China in 2016. The effect of this extensive treatment on transmitted drug resistance (TDR) of HIV is unclear. METHODS: TDR analysis was performed, based on the partial HIV-1 pol gene obtained from the newly reported HIV-1 positive cases from 2011 to 2019 in Shenzhen, China. The HIV-1 molecular transmission networks were inferred to analyse the spread of TDR. Logistic regression was used to identify the potential risk factors with TDR mutations (TDRMs) to cluster. RESULTS: A total of 12 320 partial pol sequences were included in this study. The prevalence of TDR was 2.95% (363/12 320), which increased from 2.57% to 3.52% after 'treat-all'. The TDR prevalence was increased in populations with the characteristics of CRF07_BC, being single, educated to junior college level and above, MSM and male. The sensitivities of viruses to six antiretroviral drugs were decreased. The clustering rate of TDRMs remained stable, and the sequences in the three drug resistance transmission clusters (DRTCs) were mainly found during 2011-16. CRF07_BC and CRF55_01B were the factors associated with TDRMs clustering in the networks. CONCLUSIONS: The 'treat-all' strategy might have contributed to a small increase in TDR, while most of the TDRMs were distributed sporadically, which implies that the 'treat-all' strategy is helpful for the control of TDR in high-risk populations.

Contact force catheter ablation for the treatment of persistent atrial fibrillation: Results from the PERSIST-END study.

INTRODUCTION: Use of a novel magnetic sensor enabled optical contact force ablation catheter has been established to be safe and effective for treatment of symptomatic drug-refractory paroxysmal atrial fibrillation (AF) but has yet to be demonstrated in the persistent AF (PersAF) population. METHODS: PERSIST-END was a multicenter, prospective, nonrandomized, investigational study designed to demonstrate the safety and effectiveness of TactiCath™ Ablation Catheter, Sensor Enabled™(SE) (TactiCath SE) for use in the treatment of subjects with documented PersAF refractory or intolerant to at least one Class I/III AAD. The ablation strategy included pulmonary vein isolation and additional targets at physician discretion. Follow-up through 15-months, including a 3-month blanking period and 3-month therapy consolidation period, was performed with cardiac event and Holter monitoring. Primary safety, primary effectiveness, clinical success, and quality of life (QOL) endpoints were analyzed. RESULTS: Of 224 subjects enrolled at 21 investigational sites in the United States and Australia, 223 underwent ablation with the investigational catheter. The primary safety event rate was 3.1% (seven events in seven subjects). The Kaplan-Meier estimate of freedom from AF/atrial flutter/atrial tachycardia recurrence at 15-months was 61.6% and clinical success at 15 months was 89.8%. Subject QOL significantly improved following ablation as assessed via AFEQT (31.6 point increase, p < .0001) and EQ-5D-5L (10.7 point increase, p < .0001) and was met with a 53% reduction in all cause cardiovascular healthcare utilization. CONCLUSION: The sensor-enabled force-sensing catheter is safe and effective for the treatment of drug refractory recurrent symptomatic PersAF, reducing arrhythmia recurrence while improving QOL and healthcare utilization.

Sensitisation to House Dust Mite Component Der p 23 Is Associated with Severe Symptoms and Asthma in Allergic Rhinitis Patients.

INTRODUCTION: House dust mite (HDM) is an important source of airborne allergens in China as it contains several allergenic components that can cause allergic rhinitis (AR) and other allergic diseases. This study aimed to determine the clinical characteristics and disease severity in AR patients sensitised to different allergenic HDM components. METHODS: This was a retrospective study, which examined 129 patients who were first diagnosed with only HDM-induced AR at the Department of Allergy of Beijing Tongren Hospital from December 2019 to April 2021. Clinical characteristics and disease severity of the patients were assessed based on the sensitisation to specific Dermatophagoides pteronyssinus (Der p) and Dermatophagoides farinae (Der f) allergenic components, including Der p 1, Der p 2, Der p 23, Der f 1, and Der f 2, employing multiple correspondence analysis (MCA) with correspondence analysis chart of MCA. RESULTS: Among HDM-induced AR cases, the positive rate of Der p 1 was the highest (87.6%), followed by Der p 2 (78.3%), Der f 2 (76.64%), Der f 1 (68.2%), and Der p 23 (37.2%). Multiple correspondence analyses showed that sensitisation to Der p 23 was associated with severe AR symptoms and asthma; sensitisation to Der p 2, Der f 1, and Der f 2 was associated with moderate AR; and no sensitisation to Der p 23 was associated with mild AR. CONCLUSION: Der p 23 sensitisation is prevalent in northern China and may be associated with severe symptoms and asthma in AR patients.

Baseline left atrial low-voltage area predicts recurrence after pulmonary vein isolation: WAVE-MAP AF results.

AIMS: Electro-anatomical mapping may be critical to identify atrial fibrillation (AF) subjects who require substrate modification beyond pulmonary vein isolation (PVI). The objective was to determine correlations between pre-ablation mapping characteristics and 12-month outcomes after a single PVI-only catheter ablation of AF. METHODS AND RESULTS: This study enrolled paroxysmal AF (PAF), early persistent AF (PsAF; 7 days-3 months), and non-early PsAF (>3-12 months) subjects undergoing de novo PVI-only radiofrequency catheter ablation. Sinus rhythm (SR) and AF voltage maps were created with the Advisor HD Grid™ Mapping Catheter, Sensor Enabled™ for each subject, and the presence of low-voltage area (LVA) (low-voltage cutoffs: 0.1-1.5 mV) was investigated. Follow-up visits were at 3, 6, and 12 months, with a 24-h Holter monitor at 12 months. A Cox proportional hazards model identified associations between mapping data and 12-month recurrence after a single PVI procedure. The study enrolled 300 subjects (113 PAF, 86 early PsAF, and 101 non-early PsAF) at 18 centres. At 12 months, 75.5% of subjects were free from AF/atrial flutter (AFL)/atrial tachycardia (AT) recurrence. Univariate analysis found that arrhythmia recurrence did not correlate with AF diagnosis, but LVA was significantly correlated. Low-voltage area (<0.5 mV) >28% of the left atrium in SR [hazard ratio (HR): 4.82, 95% confidence interval (CI): 2.08-11.18; P = 0.0003] and >72% in AF (HR: 5.66, 95% CI: 2.34-13.69; P = 0.0001) was associated with a higher risk of AF/AFL/AT recurrence at 12 months. CONCLUSION: Larger extension of LVA was associated with an increased risk of arrhythmia recurrence. These subjects may benefit from substrate modification beyond PVI.

Serum interα-trypsin inhibitor heavy chain H4 may be an anti-inflammatory marker reflecting disease risk, activity and treatment outcome of ankylosing spondylitis.

Interα-trypsin inhibitor heavy chain H4 (ITIH4) modulates inflammation and immunity, which take part in the pathogenesis of ankylosing spondylitis (AS). The current research intended to discover the clinical value of serum ITIH4 quantification for AS management. Serum ITIH4 among 80 AS patients before current treatment initiation (baseline) at weeks (W) 4, 8 and 12 after treatment was detected by ELISA. Serum ITIH4 from 20 disease controls (DCs) and 20 healthy controls (HCs) was detected. ITIH4 expression was lower in AS patients than in DCs (p = 0.002) and HCs (p < 0.001). Among AS patients, ITIH4 was negatively associated with C-reactive protein (CRP) (r = -0.311, p = 0.005), bath AS disease activity index (BASDAI) (r = -0.223, p = 0.047), total pack pain (r = -0.273, p = 0.014) and AS disease activity score (ASDAS) (CRP) (r = -0.265, p = 0.018). Meanwhile, ITIH4 was negatively related to tumor necrosis factor (TNF)-α (r = -0.364, p = 0.001), interleukin (IL)-1ß (r = -0.251, p = 0.025), IL-6 (r = -0.292, p = 0.009) and IL-17A (r = -0.254, p = 0.023). After treatment, the assessment of the spondylitis arthritis international society 40 response rate was 28.7% at W4, 46.3% at W8 and 55.0% at W12; ITIH4 showed an increasing trend from baseline to W12 (p < 0.001). Furthermore, ITIH4 at W8 (p = 0.020) and W12 (p = 0.035), but not at baseline or W4 (both p > 0.05), was enhanced in response patients vs. nonresponse patients. Additionally, ITIH4 at W12 was increased in AS patients receiving TNF inhibitors vs. those receiving nonsteroidal anti-inflammatory drugs (NSAIDs) (p = 0.024). Serum ITIH4 increases after treatment, and its augmentation is correlated with lower disease activity, decreased inflammation and enhanced treatment response in AS patients.

LncRNA LINC00534 regulates cell proliferation and migration via the miR-494-3p/PTEN axis in HTR-8/SVneo cells.

BACKGROUND: LncRNA LINC00534 has been found to be differentially expressed in placental tissue samples of preeclampsia (PE), but the exact mechanism is still unclear. METHODS: In vitro assays were carried out in HTR-8/SVneo cells using various methods, including cell counting kit-8 (CCK-8), transwells, flow cytometry, and Western blotting (WB) and quantitative polymerase chain reaction. RNA pull-down and bioinformatics analysis were applied to examine other potential underlying mechanisms involved. RESULTS: We found that there was a high expression of LINC00534 in the placental tissues of patients with PE. LINC00534 overexpression (OE) significantly inhibited cell proliferation and migration as well as accelerated cell apoptosis in HTR8/SVneo cells. The knockdown of LINC00534 produced an opposite trend. Mechanistically, LINC00534 promoted the expressions of PTEN (Phosphatase and tensin homolog) through decreasing miR-494-3p. Further rescue studies showed that LINC00534 played a role by targeting mir-494-3p, which controlled the growth and migration of HTR-8/SVneo trophoblast cells via regulating PTEN/PI3K/AKT (Phosphatidylinositol3-kinase/protein kinase B). Moreover, lncRNA pull-down assay identified 198 potential bound proteins for LINC00534. Those proteins were mostly involved in RNA processing and modification, posttranslational modification, protein turnover, and chaperones. CONCLUSION: Overall, by suppressing HTR8/SVneo cell growth and migration via the miR-494-3p/PTEN axis and other mechanisms, LINC00534 offers new insight into PE pathogenesis.

Comprehensive identification and characterization of the HERV-K (HML-9) group in the human genome.

BACKGROUND: Human endogenous retroviruses (HERVs) result from ancestral infections caused by exogenous retroviruses that became incorporated into the germline DNA and evolutionarily fixed in the human genome. HERVs can be transmitted vertically in a Mendelian fashion and be stably maintained in the human genome, of which they are estimated to comprise approximately 8%. HERV-K (HML1-10) transcription has been confirmed to be associated with a variety of diseases, such as breast cancer, lung cancer, prostate cancer, melanoma, rheumatoid arthritis, and amyotrophic lateral sclerosis. However, the poor characterization of HML-9 prevents a detailed understanding of the regulation of the expression of this family in humans and its impact on the host genome. In light of this, a precise and updated HERV-K HML-9 genomic map is urgently needed to better evaluate the role of these elements in human health. RESULTS: We report a comprehensive analysis of the presence and distribution of HERV-K HML-9 elements within the human genome, with a detailed characterization of the structural and phylogenetic properties of the group. A total of 23 proviruses and 47 solo LTR elements were characterized, with a detailed description of the provirus structure, integration time, potential regulated genes, transcription factor binding sites (TFBS), and primer binding site (PBS) features. The integration time results showed that the HML-9 elements found in the human genome integrated into the primate lineage between 17.5 and 48.5 million years ago (mya). CONCLUSION: The results provide a clear characterization of HML-9 and a comprehensive background for subsequent functional studies.

Amplification-Free, Single-Microbead-Based Cas12a Assay for One-Step DNA Detection at the Single-Molecule Level.

CRISPR/Cas-based systems are highly attractive for developing next-generation diagnostic technologies because of their intrinsic merits such as simplicity, sensitivity, and specificity. However, currently, nucleic acid amplification procedures are still needed to achieve attomolar sensitivity in most CRISPR/Cas-based assays, which causes high cost, operation difficulty, and low efficiency. Herein, we combine the CRISPR/Cas12a-based assay and a single-microbead detection platform for one-step and amplification-free detection of DNA at the single-molecule level. By modifying DNA reporters on a biomimetic membrane-coated microbead, the activated Cas12a by targets will cleave these reporters and lighten the bead within 10 min. The method allows the detection of the target down to three copies in a 5 µL sample. Furthermore, we successfully apply this method for the specific identification of viral infection, foodborne bacteria, and DNA mutation in real samples without extra nucleic acid amplification. We believe that this approach offers new insights for developing CRISPR/Cas-based DNA assays in biomedical applications.

A Hemicyanine-Assembled Upconversion Nanosystem for NIR-Excited Visualization of Carbon Monoxide Bio-Signaling In Vivo.

Carbon monoxide (CO) is considered as the second gasotransmitter involved in a series of physiological and pathological processes. Although a number of organic fluorescent probes have been developed for imaging CO, these probes display excitation within the ultraviolet or visible range, which restrict their applications in the complex biosystems. In the present work, a strategy is developed to construct an upconversion nanoparticles-based nanosystem for upconversion luminescent (UCL) sensing CO. This nanosystem exhibits a fast response to CO with high sensitivity and selectivity in aqueous solution by a near-infrared-excited ratiometric UCL detection method. Meanwhile, laser scanning upconversion luminescence microscope experiments demonstrate that this nanosystem can visualize the endogenous CO bio-signaling in living cells, deep tissues, zebrafish, and living mice by ratiometric UCL imaging. In particular, this nanosystem has been successfully employed in visualization of the endogenous CO bio-signaling through up-regulation of heme oxygenase-1 (HO-1) in the progression of hypoxia, acute inflammation, or ischemic injury. This work demonstrates that the outstanding performance of the nanosystem not only can provide an effective tool for further understanding the role of CO in the physiological and pathological environment, but also may have great potential ability for tracking the expression of HO-1 in living systems.

All-trans retinoic acid increases the pathogenicity of the H9N2 influenza virus in mice.

BACKGROUND: The H9N2 virus can infect not only birds but also humans. The pathogenicity of H9N2 virus infection is determined by an excessive immune response in the lung. All-trans retinoic acid (ATRA), the active metabolite of vitamin A, plays an important regulatory role and has been widely used in the clinical practice. This study was aimed to investigate whether ATRA could regulate the immune response to H9N2 virus infection in the lungs of mice, thereby reducing the pathogenicity of the H9N2 virus in mice. METHODS: Mice were infected intranasally with H9N2 virus, and injected intraperitoneally with 0.2 mL of ATRA at low (1 mg/kg), medium (5 or 10 mg/kg), or high therapeutic dose (20 mg/kg), and toxic dose (40, 60, or 80 mg/kg), once per day for 10 days. Clinical signs, survival rates, and lung gross pathology were compared between the ATRA-treated H9N2-infected group, the ATRA group, and the H9N2-infected group, to investigate the effect of different doses of ATRA on the pathogenicity of H9N2 virus. Additionally, the viral load and cytokine concentration of lungs were measured at 3, 5, 7, and 9 days after infection, to investigate the potential mechanism of ATRA in affecting the pathogenicity of the H9N2 virus. Expression levels of cellular retinoic acid-binding protein 1 (CRABP1), cellular retinoic acid-binding protein 2 (CRABP2), and Retinoic acid-inducible gene-I (RIG-I) were detected using Western blotting. RESULTS: The ATRA-treated H9N2-infected mice showed more severe clinical signs compared with the H9N2-infected group. The medium and high therapeutic doses of ATRA reduced the survival rates, aggravated lung tissue damage, decreased the expression of interferon beta (IFN-ß), and increased the concentrations of interleukin-1 beta (IL-1ß), tumor necrosis factor alpha (TNF-α), and C-C motif chemokine ligand 2 (CCL2) in the lungs of the H9N2-infected mice. At the same time, the expression patterns of CRABP1, CRABP2, and RIG-I were changed in mice infected by H9N2 and treated with different concentrations of ATRA. CONCLUSIONS: Our findings suggest that the therapeutic dose of ATRA can increase the pathogenicity of the H9N2 virus. Therefore, the consequences of those infected by influenza virus would be more severe after ATRA treatment.