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1.
Nature ; 2024 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-39232169

RESUMO

Futuristic technologies such as morphing aircrafts and super-strong artificial muscles depend on metal alloys being as strong as ultrahigh-strength steel yet as flexible as a polymer1-3. However, achieving such 'strong yet flexible' alloys has proven challenging4-9 because of the inevitable trade-off between strength and flexibility5,8,10. Here we report a Ti-50.8 at.% Ni strain glass alloy showing a combination of ultrahigh yield strength of σy ≈ 1.8 GPa and polymer-like ultralow elastic modulus of E ≈ 10.5 GPa, together with super-large rubber-like elastic strain of approximately 8%. As a result, it possesses a high flexibility figure of merit of σy/E ≈ 0.17 compared with existing structural materials. In addition, it can maintain such properties over a wide temperature range of -80 °C to +80 °C and demonstrates excellent fatigue resistance at high strain. The alloy was fabricated by a simple three-step thermomechanical treatment that is scalable to industrial lines, which leads not only to ultrahigh strength because of deformation strengthening, but also to ultralow modulus by the formation of a unique 'dual-seed strain glass' microstructure, composed of a strain glass matrix embedded with a small number of aligned R and B19' martensite 'seeds'. In situ X-ray diffractometry shows that the polymer-like deformation behaviour of the alloy originates from a nucleation-free reversible transition between strain glass and R and B19' martensite during loading and unloading. This exotic alloy with the potential for mass producibility may open a new horizon for many futuristic technologies, such as morphing aerospace vehicles, superman-type artificial muscles and artificial organs.

2.
Mol Cell ; 82(22): 4340-4352.e6, 2022 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-36309016

RESUMO

Adhesion G-protein-coupled receptors (aGPCRs) play key roles in a diversity of physiologies. A hallmark of aGPCR activation is the removal of the inhibitory GAIN domain and the dipping of the cleaved stalk peptide into the ligand-binding pocket of receptors; however, the detailed mechanism remains obscure. Here, we present cryoelectron microscopy (cryo-EM) structures of ADGRL3 in complex with Gq, Gs, Gi, and G12. The structures reveal unique ligand-engaging mode, distinctive activation conformation, and key mechanisms of aGPCR activation. The structures also reveal the uncharted structural information of GPCR/G12 coupling. A comparison of Gq, Gs, Gi, and G12 engagements with ADGRL3 reveals the key determinant of G-protein coupling on the far end of αH5 of Gα. A detailed analysis of the engagements allows us to design mutations that specifically enhance one pathway over others. Taken together, our study lays the groundwork for understanding aGPCR activation and G-protein-coupling selectivity.


Assuntos
Proteínas de Ligação ao GTP , Receptores Acoplados a Proteínas G , Ligantes , Microscopia Crioeletrônica , Receptores Acoplados a Proteínas G/metabolismo , Proteínas de Ligação ao GTP/metabolismo
3.
Brief Bioinform ; 25(2)2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38517696

RESUMO

With the rapid development of single-molecule sequencing (SMS) technologies, the output read length is continuously increasing. Mapping such reads onto a reference genome is one of the most fundamental tasks in sequence analysis. Mapping sensitivity is becoming a major concern since high sensitivity can detect more aligned regions on the reference and obtain more aligned bases, which are useful for downstream analysis. In this study, we present pathMap, a novel k-mer graph-based mapper that is specifically designed for mapping SMS reads with high sensitivity. By viewing the alignment chain as a path containing as many anchors as possible in the matched k-mer graph, pathMap treats chaining as a path selection problem in the directed graph. pathMap iteratively searches the longest path in the remaining nodes; more candidate chains with high quality can be effectively detected and aligned. Compared to other state-of-the-art mapping methods such as minimap2 and Winnowmap2, experiment results on simulated and real-life datasets demonstrate that pathMap obtains the number of mapped chains at least 11.50% more than its closest competitor and increases the mapping sensitivity by 17.28% and 13.84% of bases over the next-best mapper for Pacific Biosciences and Oxford Nanopore sequencing data, respectively. In addition, pathMap is more robust to sequence errors and more sensitive to species- and strain-specific identification of pathogens using MinION reads.


Assuntos
Sequenciamento de Nucleotídeos em Larga Escala , Sequenciamento por Nanoporos , Análise de Sequência de DNA/métodos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Genoma , Software , Algoritmos
4.
PLoS Genet ; 19(7): e1010786, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37459304

RESUMO

Human ear morphology, a complex anatomical structure represented by a multidimensional set of correlated and heritable phenotypes, has a poorly understood genetic architecture. In this study, we quantitatively assessed 136 ear morphology traits using deep learning analysis of digital face images in 14,921 individuals from five different cohorts in Europe, Asia, and Latin America. Through GWAS meta-analysis and C-GWASs, a recently introduced method to effectively combine GWASs of many traits, we identified 16 genetic loci involved in various ear phenotypes, eight of which have not been previously associated with human ear features. Our findings suggest that ear morphology shares genetic determinants with other surface ectoderm-derived traits such as facial variation, mono eyebrow, and male pattern baldness. Our results enhance the genetic understanding of human ear morphology and shed light on the shared genetic contributors of different surface ectoderm-derived phenotypes. Additionally, gene editing experiments in mice have demonstrated that knocking out the newly ear-associated gene (Intu) and a previously ear-associated gene (Tbx15) causes deviating mouse ear morphology.


Assuntos
Loci Gênicos , Estudo de Associação Genômica Ampla , Humanos , Masculino , Animais , Camundongos , Estudo de Associação Genômica Ampla/métodos , Fenótipo , Ásia , Polimorfismo de Nucleotídeo Único/genética
5.
J Virol ; 98(4): e0013924, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38501663

RESUMO

Swine acute diarrhea syndrome coronavirus (SADS-CoV) is a novel porcine enteric coronavirus, and the broad interspecies infection of SADS-CoV poses a potential threat to human health. This study provides experimental evidence to dissect the roles of distinct domains within the SADS-CoV spike S1 subunit in cellular entry. Specifically, we expressed the S1 and its subdomains, S1A and S1B. Cell binding and invasion inhibition assays revealed a preference for the S1B subdomain in binding to the receptors on the cell surface, and this unknown receptor is not utilized by the porcine epidemic diarrhea virus. Nanoparticle display demonstrated hemagglutination of erythrocytes from pigs, humans, and mice, linking the S1A subdomain to the binding of sialic acid (Sia) involved in virus attachment. We successfully rescued GFP-labeled SADS-CoV (rSADS-GFP) from a recombinant cDNA clone to track viral infection. Antisera raised against S1, S1A, or S1B contained highly potent neutralizing antibodies, with anti-S1B showing better efficiency in neutralizing rSADS-GFP infection compared to anti-S1A. Furthermore, depletion of heparan sulfate (HS) by heparinase treatment or pre-incubation of rSADS-GFP with HS or constituent monosaccharides could inhibit SADS-CoV entry. Finally, we demonstrated that active furin cleavage of S glycoprotein and the presence of type II transmembrane serine protease (TMPRSS2) are essential for SADS-CoV infection. These combined observations suggest that the wide cell tropism of SADS-CoV may be related to the distribution of Sia or HS on the cell surface, whereas the S1B contains the main protein receptor binding site. Specific host proteases also play important roles in facilitating SADS-CoV entry.IMPORTANCESwine acute diarrhea syndrome coronavirus (SADS-CoV) is a novel pathogen infecting piglet, and its unique genetic evolution characteristics and broad species tropism suggest the potential for cross-species transmission. The virus enters cells through its spike (S) glycoprotein. In this study, we identify the receptor binding domain on the C-terminal part of the S1 subunit (S1B) of SADS-CoV, whereas the sugar-binding domain located at the S1 N-terminal part of S1 (S1A). Sialic acid, heparan sulfate, and specific host proteases play essential roles in viral attachment and entry. The dissection of SADS-CoV S1 subunit's functional domains and identification of cellular entry cofactors will help to explore the receptors used by SADS-CoV, which may contribute to exploring the mechanisms behind cross-species transmission and host tropism.


Assuntos
Alphacoronavirus , Infecções por Coronavirus , Glicoproteína da Espícula de Coronavírus , Animais , Humanos , Camundongos , Alphacoronavirus/química , Alphacoronavirus/fisiologia , Infecções por Coronavirus/veterinária , Infecções por Coronavirus/virologia , Heparitina Sulfato , Ácido N-Acetilneuramínico/metabolismo , Peptídeo Hidrolases , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/metabolismo , Suínos
6.
Am J Physiol Cell Physiol ; 327(3): C737-C749, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-39069827

RESUMO

The mitochondrial citrate shuttle, which relies on the solute carrier family 25 member 1 (SLC25A1), plays a pivotal role in transporting citrate from the mitochondria to the cytoplasm. This shuttle supports glycolysis, lipid biosynthesis, and protein acetylation. Previous research has primarily focused on SLC25A1 in pathological models, particularly high-fat diet (HFD)-induced obesity. However, the impact of SLC25A1 inhibition on nutrient metabolism under HFD remains unclear. To address this gap, we used zebrafish (Danio rerio) and Nile tilapia (Oreochromis niloticus) to evaluate the effects of inhibiting Slc25a1. In zebrafish, we administered Slc25a1-specific inhibitors (CTPI-2) for 4 wk, whereas Nile tilapia received intraperitoneal injections of dsRNA to knock down slc25a1b for 7 days. Inhibition of the mitochondrial citrate shuttle effectively protected zebrafish from HFD-induced obesity, hepatic steatosis, and insulin resistance. Of note, glucose tolerance was unaffected. Inhibition of Slc25a1 altered hepatic protein acetylation patterns, with decreased cytoplasmic acetylation and increased mitochondrial acetylation. Under HFD conditions, Slc25a1 inhibition promoted fatty acid oxidation and reduced hepatic triglyceride (TAG) accumulation by deacetylating carnitine palmitoyltransferase 1a (Cpt1a). In addition, Slc25a1 inhibition triggered acetylation-induced inactivation of Pdhe1α, leading to a reduction in glucose oxidative catabolism. This was accompanied by enhanced glucose uptake and storage in zebrafish livers. Furthermore, Slc25a1 inhibition under HFD conditions activated the SIRT1/PGC1α pathway, promoting mitochondrial proliferation and enhancing oxidative phosphorylation for energy production. Our findings provide new insights into the role of nonhistone protein acetylation via the mitochondrial citrate shuttle in the development of hepatic lipid deposition and hyperglycemia caused by HFD.NEW & NOTEWORTHY The mitochondrial citrate shuttle is a crucial physiological process for maintaining metabolic homeostasis. In the present study, we found that inhibition of mitochondrial citrate shuttle (Slc25a1) could alleviate metabolic syndromes induced by high-fat diet (HFD) through remodeling hepatic protein acetylation modification. Briefly, Slc25a1 inhibition reduces hepatic triglyceride deposition by deacetylating Cpt1a and reduces glucose oxidative catabolism by acetylating Pdhe1α. Our study provides new insights into the treatment of diet-induced metabolic syndromes.


Assuntos
Ácido Cítrico , Dieta Hiperlipídica , Peixe-Zebra , Animais , Dieta Hiperlipídica/efeitos adversos , Ácido Cítrico/metabolismo , Síndrome Metabólica/metabolismo , Síndrome Metabólica/prevenção & controle , Síndrome Metabólica/genética , Síndrome Metabólica/etiologia , Mitocôndrias/metabolismo , Mitocôndrias/efeitos dos fármacos , Carnitina O-Palmitoiltransferase/metabolismo , Carnitina O-Palmitoiltransferase/genética , Obesidade/metabolismo , Obesidade/prevenção & controle , Obesidade/genética , Obesidade/etiologia , Acetilação , Proteínas de Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/genética , Fígado/metabolismo , Fígado/efeitos dos fármacos , Fígado/patologia , Masculino , Resistência à Insulina , Fígado Gorduroso/metabolismo , Fígado Gorduroso/prevenção & controle , Fígado Gorduroso/patologia , Fígado Gorduroso/etiologia , Metabolismo dos Lipídeos/efeitos dos fármacos
7.
J Am Chem Soc ; 146(23): 15908-15916, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38809425

RESUMO

Efficient transformation of platform chemicals into key intermediates has been increasingly important for the pharmaceutical industry. The development of the catalytic reduction of abundant carboxylic acids with molecular hydrogen has been of both practical and theoretical value. We herein report the homogeneous hydrogenation of dicarboxylic acids with the strategy of desymmetrization. Using a rhodium/bisphosphine catalyst, one carboxyl group of meso-diacids was selectively reduced to yield chiral lactones with satisfactory enantioselectivity. This method provides a straightforward approach to produce chiral lactone intermediates for the manufacture of biotin, telaprevir, and other antivirus drugs. Both experimental and computational investigations were carried out, revealing a novel neighboring group coordination mechanism in the catalytic cycle.

8.
J Am Chem Soc ; 146(19): 13306-13316, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38690945

RESUMO

Traditional superwettable membranes for demulsification of oil/water emulsions could not maintain their separation performance for long because of low demulsification capacity and surface fouling during practical applications. A charging membrane could repel the contaminants for a while, the charge of which would gradually be neutralized during the separation progress. Here, a superhydrophilic piezoelectric membrane (SPM) with sustained demulsification and antifouling capacity is proposed for achieving prolonged emulsion separation, which is capable of converting inherent pulse hydraulic filtration pressure into pulse voltage. A pulse voltage up to -7.6 V is generated to intercept the oil by expediting the deformation and coalescence of emulsified oil droplets, realizing the demulsification. Furthermore, it repels negatively charged oil droplets, avoiding membrane fouling. Additionally, any organic foulants adhering to the membrane undergo degradation facilitated by the generated reactive oxygen species. The separation data demonstrate a 98.85% efficiency with a flux decline ratio below 14% during a 2 h separation duration and a nearly 100% flux recovery of SPM. This research opens new avenues in membrane separation, environmental remediation, etc.

9.
J Am Chem Soc ; 146(33): 23121-23137, 2024 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-38980064

RESUMO

Addressing the global challenge of bacterial resistance demands innovative approaches, among which multitargeting is a widely used strategy. Current strategies of multitargeting, typically achieved through drug combinations or single agents inherently aiming at multiple targets, face challenges such as stringent pharmacokinetic and pharmacodynamic requirements and cytotoxicity concerns. In this report, we propose a bacterial-specific global disruption approach as a vastly expanded multitargeting strategy that effectively disrupts bacterial subcellular organization. This effect is achieved through a pioneering chemical design of ligand-receptor interaction-induced aggregation of small molecules, i.e., DNA-induced aggregation of a diarginine peptidomimetic within bacterial cells. These intracellular aggregates display affinity toward various proteins and thus substantially interfere with essential bacterial functions and rupture bacterial cell membranes in an "inside-out" manner, leading to robust antibacterial activities and suppression of drug resistance. Additionally, biochemical analysis of macromolecule binding affinity, cytoplasmic localization patterns, and bacterial stress responses suggests that this bacterial-specific intracellular aggregation mechanism is fundamentally different from nonselective classic DNA or membrane binding mechanisms. These mechanistic distinctions, along with the peptidomimetic's selective permeation of bacterial membranes, contribute to its favorable biocompatibility and pharmacokinetic properties, enabling its in vivo antimicrobial efficacy in several animal models, including mice-based superficial wound models, subcutaneous abscess models, and septicemia infection models. These results highlight the great promise of ligand-receptor interaction-induced intracellular aggregation in achieving a globally disruptive multitargeting effect, thereby offering potential applications in the treatment of malignant cells, including pathogens, tumor cells, and infected tissues.


Assuntos
Antibacterianos , Ligantes , Animais , Antibacterianos/farmacologia , Antibacterianos/química , Camundongos , Testes de Sensibilidade Microbiana , Farmacorresistência Bacteriana/efeitos dos fármacos , Peptidomiméticos/farmacologia , Peptidomiméticos/química , Separação de Fases
10.
Mol Cancer ; 23(1): 198, 2024 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-39272149

RESUMO

Tumor cells remodel the phenotype and function of tumor microenvironment (TME) cells to favor tumor progression. Previous studies have shown that neutrophils in TME are polarized to N2 tumor-associated neutrophils (TANs) by tumor derived factors, thus promoting tumor growth and metastasis, angiogenesis, therapy resistance, and immunosuppression. Exosomes act as critical intercellular messengers in human health and diseases including cancer. So far, the biological roles of exosomes from N2 TANs in gastric cancer have not been well characterized. Herein, we represented the first report that exosomes from N2 TANs promoted gastric cancer metastasis in vitro and in vivo. We found that exosomes from N2 TANs transferred miR-4745-5p/3911 to gastric cancer cells to downregulate SLIT2 (slit guidance ligand 2) gene expression. Adenovirus-mediated overexpression of SLIT2 reversed the promotion of gastric cancer metastasis by N2 TANs derived exosomes. We further revealed that gastric cancer cells induced glucose metabolic reprogramming in neutrophils through exosomal HMGB1 (high mobility group protein B1)/NF-κB pathway, which mediated neutrophil N2 polarization and miR-4745-5p/3911 upregulation. We further employed ddPCR (droplet digital PCR) to detect the expression of miR-4745-5p/3911 in N2 TANs exosomes from human serum samples and found their increased levels in gastric cancer patients compared to healthy controls and benign gastric disease patients. Conclusively, our results indicate that N2 TANs facilitate cancer metastasis via regulation of SLIT2 in gastric cancer cells by exosomal miR-4745-5p/3911, which provides a new insight into the roles of TME cells derived exosomes in gastric cancer metastasis and offers a potential biomarker for gastric cancer diagnosis.


Assuntos
Exossomos , Regulação Neoplásica da Expressão Gênica , Peptídeos e Proteínas de Sinalização Intercelular , MicroRNAs , Proteínas do Tecido Nervoso , Neutrófilos , Neoplasias Gástricas , Microambiente Tumoral , Neoplasias Gástricas/patologia , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Exossomos/metabolismo , Exossomos/genética , Humanos , Neutrófilos/metabolismo , Neutrófilos/patologia , MicroRNAs/genética , Animais , Camundongos , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Linhagem Celular Tumoral , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/genética , Microambiente Tumoral/genética , Metástase Neoplásica , Proteína HMGB1/metabolismo , Proteína HMGB1/genética , Masculino
11.
Mol Cancer ; 23(1): 128, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38890620

RESUMO

BACKGROUND: Circular RNAs (circRNAs) play important roles in cancer progression and metastasis. However, the expression profiles and biological roles of circRNAs in non-small cell lung cancer (NSCLC) remain unclear. METHODS: In this study, we identified a novel circRNA, hsa_circ_0006834 (termed circ6834), in NSCLC by RNA-seq and investigated the biological role of circ6834 in NSCLC progression in vitro and in vivo. Finally, the molecular mechanism of circ6834 was revealed by tagged RNA affinity purification (TRAP), western blot, RNA immunoprecipitation, dual luciferase reporter gene assays and rescue experiments. RESULTS: Our results showed that circ6834 was downregulated in NSCLC tumor tissues and cell lines. Circ6834 overexpression inhibited NSCLC cell growth and metastasis both in vitro and in vivo, while circ6834 knockdown had the opposite effect. We found that TGF-ß treatment decreased circ6834 expression, which was associated with the QKI reduction in NSCLC cells and circ6834 antagonized TGF-ß-induced EMT and metastasis in NSCLC cells. Mechanistically, circ6834 bound to AHNAK protein, a key regulator of TGF-ß/Smad signaling, and inhibited its stability by enhancing TRIM25-mediated ubiquitination and degradation. In addition, circ6834 acted as a miRNA sponge for miR-873-5p and upregulated TXNIP gene expression, which together inactivated the TGF-ß/Smad signaling pathway in NSCLC cells. CONCLUSION: In conclusion, circ6834 is a tumor-suppressive circRNA that inhibits NSCLC progression by forming a negative regulatory feedback loop with the TGF-ß/Smad signaling pathway and represents a novel therapeutic target for NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Proteínas de Transporte , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Neoplasias Pulmonares , MicroRNAs , RNA Circular , Humanos , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/metabolismo , RNA Circular/genética , MicroRNAs/genética , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/metabolismo , Animais , Camundongos , Linhagem Celular Tumoral , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Progressão da Doença , Movimento Celular/genética , Transdução de Sinais , Feminino , Fator de Crescimento Transformador beta/metabolismo , Masculino , Transição Epitelial-Mesenquimal/genética
12.
Immunogenetics ; 2024 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-39183206

RESUMO

Systemic lupus erythematosus (SLE) is a complex autoimmune disorder, the etiology of which involves the alterations in circulating cytokine levels. However, the cause-and-effect relationships and in-depth clinical relevance of them remain to be systematically investigated. We conducted a two-sample Mendelian randomization (MR) study to assess the causality of circulating cytokine levels and SLE and found that genetically determined elevated CTACK and IL-18 were associated with an increased risk of SLE, whereas a higher level of GRO-a was associated with decreased risk. Furthermore, we performed an observational study to further reveal the association between 27 cytokines and the severity measured by SLEDAI score, as well as lupus nephritis (LN), of SLE. We identified six cytokines (MCP1, MIP1ß, CTACK, IP10, HGF, IL18, IL13) that were identified as associated with the clinical severity of SLE, and five cytokines, especially IL18, were related with LN and may have good diagnostic value. Moreover, we also predicted four compounds that might have good binding activities with IL18. The evidence supported a potential causal role of circulating cytokines on the risk of SLE. Targeting IL18 might be a meaningful strategy for the prevention or treatment of SLE, especially in LN patients.

13.
Biochem Biophys Res Commun ; 692: 149323, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38043154

RESUMO

Osteoporosis is a metabolic bone loss disorder usually accompanied by overactivated osteoclast formation and increased bone resorption. Transcriptional co-activator with PDZ-binding motif (TAZ) is an emerging potential target for the treatment of osteoporosis. Our previous research showed that TAZ overexpression inhibited osteoclast formation while TAZ silencing had the opposite effect. In addition, TAZ knockout in mouse osteoclasts induced osteoporosis in animal experiments. XMU-MP-1 (XMU) is a selective MST1/2 inhibitor that can theoretically activate TAZ; however, its effect on osteoporosis remains unknown. In this study, we found that XMU treatment significantly increased TAZ expression in osteoclasts and inhibited osteoclast formation in vitro; however, this inhibitory effect was eliminated after the deletion of TAZ. Furthermore, XMU treatment upregulated TAZ expression in osteoclasts and alleviated ovariectomy (OVX)-induced osteoporosis in bilateral OVX mouse models. These findings suggest that XMU can effectively activate TAZ and that pharmacological activation of TAZ may be a promising option for the treatment of osteoporosis.


Assuntos
Osteogênese , Osteoporose , Camundongos , Animais , Feminino , Humanos , Osso Esponjoso , Osteoporose/etiologia , Osteoporose/induzido quimicamente , Fatores de Transcrição/genética , Fatores de Transcrição/farmacologia , Ovariectomia
14.
BMC Med ; 22(1): 152, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38589871

RESUMO

BACKGROUND: Despite substantial research revealing that patients with rheumatoid arthritis (RA) have excessive morbidity and mortality of cardiovascular disease (CVD), the mechanism underlying this association has not been fully known. This study aims to systematically investigate the phenotypic and genetic correlation between RA and CVD. METHODS: Based on UK Biobank, we conducted two cohort studies to evaluate the phenotypic relationships between RA and CVD, including atrial fibrillation (AF), coronary artery disease (CAD), heart failure (HF), and stroke. Next, we used linkage disequilibrium score regression, Local Analysis of [co]Variant Association, and bivariate causal mixture model (MiXeR) methods to examine the genetic correlation and polygenic overlap between RA and CVD, using genome-wide association summary statistics. Furthermore, we explored specific shared genetic loci by conjunctional false discovery rate analysis and association analysis based on subsets. RESULTS: Compared with the general population, RA patients showed a higher incidence of CVD (hazard ratio [HR] = 1.21, 95% confidence interval [CI]: 1.15-1.28). We observed positive genetic correlations of RA with AF and stroke, and a mixture of negative and positive local genetic correlations underlying the global genetic correlation for CAD and HF, with 13 ~ 33% of shared genetic variants for these trait pairs. We further identified 23 pleiotropic loci associated with RA and at least one CVD, including one novel locus (rs7098414, TSPAN14, 10q23.1). Genes mapped to these shared loci were enriched in immune and inflammatory-related pathways, and modifiable risk factors, such as high diastolic blood pressure. CONCLUSIONS: This study revealed the shared genetic architecture of RA and CVD, which may facilitate drug target identification and improved clinical management.


Assuntos
Artrite Reumatoide , Doenças Cardiovasculares , Doença da Artéria Coronariana , Insuficiência Cardíaca , Acidente Vascular Cerebral , Humanos , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/genética , Estudo de Associação Genômica Ampla/métodos , Predisposição Genética para Doença/genética , Artrite Reumatoide/genética , Artrite Reumatoide/epidemiologia , Doença da Artéria Coronariana/genética , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/genética , Polimorfismo de Nucleotídeo Único/genética
15.
BMC Med ; 22(1): 357, 2024 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-39227839

RESUMO

BACKGROUND: Our previous genome­wide association studies (GWAS) have suggested rs912304 in 14q12 as a suggestive risk variant for type 1 diabetes (T1D). However, the association between this risk region and T1D subgroups and related clinical risk features, the underlying causal functional variant(s), putative candidate gene(s), and related mechanisms are yet to be elucidated. METHODS: We assessed the association between variant rs912304 and T1D, as well as islet autoimmunity and islet function, stratified by the diagnosed age of 12. We used epigenome bioinformatics analyses, dual luciferase reporter assays, and expression quantitative trait loci (eQTL) analyses to prioritize the most likely functional variant and potential causal gene. We also performed functional experiments to evaluate the role of the causal gene on islet function and its related mechanisms. RESULTS: We identified rs912304 as a risk variant for T1D subgroups with diagnosed age ≥ 12 but not < 12. This variant is associated with residual islet function but not islet-specific autoantibody positivity in T1D individuals. Bioinformatics analysis indicated that rs912304 is a functional variant exhibiting spatial overlaps with enhancer active histone marks (H3K27ac and H3K4me1) and open chromatin status (ATAC-seq) in the human pancreas and islet tissues. Luciferase reporter gene assays and eQTL analyses demonstrated that the biallelic sites of rs912304 had differential allele-specific enhancer activity in beta cell lines and regulated STXBP6 expression, which was defined as the most putative causal gene based on Open Targets Genetics, GTEx v8 and Tiger database. Moreover, Stxbp6 was upregulated by T1D-related proinflammatory cytokines but not high glucose/fat. Notably, Stxbp6 over-expressed INS-1E cells exhibited decreasing insulin secretion and increasing cell apoptosis through Glut1 and Gadd45ß, respectively. CONCLUSIONS: This study expanded the genomic landscape regarding late-onset T1D risk and supported islet function mechanistically connected to T1D pathogenesis.


Assuntos
Diabetes Mellitus Tipo 1 , Ilhotas Pancreáticas , Humanos , Diabetes Mellitus Tipo 1/genética , Ilhotas Pancreáticas/metabolismo , Feminino , Masculino , Polimorfismo de Nucleotídeo Único/genética , Predisposição Genética para Doença , Citocinas/genética , Citocinas/metabolismo , Criança , Adolescente , Locos de Características Quantitativas , Animais , Idade de Início , Regulação da Expressão Gênica , Estudo de Associação Genômica Ampla
16.
J Neuroinflammation ; 21(1): 161, 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38915059

RESUMO

BACKGROUND: Pediatric acute transverse myelitis (ATM) accounts for 20-30% of children presenting with a first acquired demyelinating syndrome (ADS) and may be the first clinical presentation of a relapsing ADS such as multiple sclerosis (MS). B cells have been strongly implicated in the pathogenesis of adult MS. However, little is known about B cells in pediatric MS, and even less so in pediatric ATM. Our lab previously showed that plasmablasts (PB), the earliest B cell subtype producing antibody, are expanded in adult ATM, and that these PBs produce self-reactive antibodies that target neurons. The goal of this study was to examine PB frequency and phenotype, immunoglobulin selection, and B cell receptor reactivity in pediatric patients presenting with ATM to gain insight to B cell involvement in disease. METHODS: We compared the PB frequency and phenotype of 5 pediatric ATM patients and 10 pediatric healthy controls (HC) and compared them to previously reported adult ATM patients using cytometric data. We purified bulk IgG from the plasma samples and cloned 20 recombinant human antibodies (rhAbs) from individual PBs isolated from the blood. Plasma-derived IgG and rhAb autoreactivity was measured by mean fluorescence intensity (MFI) in neurons and astrocytes of murine brain or spinal cord and primary human astrocytes. We determined the potential impact of these rhAbs on astrocyte health by measuring stress and apoptotic response. RESULTS: We found that pediatric ATM patients had a reduced frequency of peripheral blood PB. Serum IgG autoreactivity to neurons in EAE spinal cord was similar in the pediatric ATM patients and HC. However, serum IgG autoreactivity to astrocytes in EAE spinal cord was reduced in pediatric ATM patients compared to pediatric HC. Astrocyte-binding strength of rhAbs cloned from PBs was dependent on somatic hypermutation accumulation in the pediatric ATM cohort, but not HC. A similar observation in predilection for astrocyte binding over neuron binding of individual antibodies cloned from PBs was made in EAE brain tissue. Finally, exposure of human primary astrocytes to these astrocyte-binding antibodies increased astrocytic stress but did not lead to apoptosis. CONCLUSIONS: Discordance in humoral immune responses to astrocytes may distinguish pediatric ATM from HC.


Assuntos
Astrócitos , Mielite Transversa , Humanos , Mielite Transversa/imunologia , Animais , Feminino , Astrócitos/metabolismo , Astrócitos/imunologia , Criança , Camundongos , Masculino , Adolescente , Plasmócitos/imunologia , Plasmócitos/metabolismo , Autoanticorpos/imunologia , Autoanticorpos/sangue , Camundongos Endogâmicos C57BL , Células Cultivadas , Pré-Escolar , Imunoglobulina G/imunologia , Imunoglobulina G/sangue , Medula Espinal/metabolismo , Medula Espinal/imunologia , Medula Espinal/patologia
17.
Bioinformatics ; 39(12)2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-38058196

RESUMO

MOTIVATION: Longer reads produced by PacBio or Oxford Nanopore sequencers could more frequently span the breakpoints of structural variations (SVs) than shorter reads. Therefore, existing long-read mapping methods often generate wrong alignments and variant calls. Compared to deletions and insertions, inversion events are more difficult to be detected since the anchors in inversion regions are nonlinear to those in SV-free regions. To address this issue, this study presents a novel long-read mapping algorithm (named as invMap). RESULTS: For each long noisy read, invMap first locates the aligned region with a specifically designed scoring method for chaining, then checks the remaining anchors in the aligned region to discover potential inversions. We benchmark invMap on simulated datasets across different genomes and sequencing coverages, experimental results demonstrate that invMap is more accurate to locate aligned regions and call SVs for inversions than the competing methods. The real human genome sequencing dataset of NA12878 illustrates that invMap can effectively find more candidate variant calls for inversions than the competing methods. AVAILABILITY AND IMPLEMENTATION: The invMap software is available at https://github.com/zhang134/invMap.git.


Assuntos
Genômica , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Genômica/métodos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Software , Algoritmos , Genoma Humano , Inversão Cromossômica , Análise de Sequência de DNA/métodos
18.
Bioinformatics ; 39(10)2023 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-37756695

RESUMO

MOTIVATION: Precise identification of cancer cells in patient samples is essential for accurate diagnosis and clinical monitoring but has been a significant challenge in machine learning approaches for cancer precision medicine. In most scenarios, training data are only available with disease annotation at the subject or sample level. Traditional approaches separate the classification process into multiple steps that are optimized independently. Recent methods either focus on predicting sample-level diagnosis without identifying individual pathologic cells or are less effective for identifying heterogeneous cancer cell phenotypes. RESULTS: We developed a generalized end-to-end differentiable model, the Cell Scoring Neural Network (CSNN), which takes sample-level training data and predicts the diagnosis of the testing samples and the identity of the diagnostic cells in the sample, simultaneously. The cell-level density differences between samples are linked to the sample diagnosis, which allows the probabilities of individual cells being diagnostic to be calculated using backpropagation. We applied CSNN to two independent clinical flow cytometry datasets for leukemia diagnosis. In both qualitative and quantitative assessments, CSNN outperformed preexisting neural network modeling approaches for both cancer diagnosis and cell-level classification. Post hoc decision trees and 2D dot plots were generated for interpretation of the identified cancer cells, showing that the identified cell phenotypes match the cancer endotypes observed clinically in patient cohorts. Independent data clustering analysis confirmed the identified cancer cell populations. AVAILABILITY AND IMPLEMENTATION: The source code of CSNN and datasets used in the experiments are publicly available on GitHub (http://github.com/erobl/csnn). Raw FCS files can be downloaded from FlowRepository (ID: FR-FCM-Z6YK).


Assuntos
Neoplasias Hematológicas , Neoplasias , Humanos , Redes Neurais de Computação , Neoplasias/diagnóstico , Citometria de Fluxo/métodos , Software
19.
J Transl Med ; 22(1): 364, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38632610

RESUMO

BACKGROUND: Polycystic ovary syndrome (PCOS) is an endocrinological and metabolic disorder that can lead to female infertility. Lipid metabolomics and proteomics are the new disciplines in systems biology aimed to discover metabolic pathway changes in diseases and diagnosis of biomarkers. This study aims to reveal the features of PCOS to explore its pathogenesis at the protein and metabolic level. METHODS: We collected follicular fluid samples and granulosa cells of women with PCOS and normal women who underwent in vitro fertilization(IVF) and embryo transfer were recruited. The samples were for the lipidomic study and the proteomic study based on the latest metabolomics and proteomics research platform. RESULTS: Lipid metabolomic analysis revealed abnormal metabolism of glycerides, glycerophospholipids, and sphingomyelin in the FF of PCOS. Differential lipids were strongly linked with the rate of high-quality embryos. In total, 144 differentially expressed proteins were screened in ovarian granulosa cells in women with PCOS compared to controls. Go functional enrichment analysis showed that differential proteins were associated with blood coagulation and lead to follicular development disorders. CONCLUSION: The results showed that the differential lipid metabolites and proteins in PCOS were closely related to follicle quality,which can be potential biomarkers for oocyte maturation and ART outcomes.


Assuntos
Síndrome do Ovário Policístico , Feminino , Humanos , Líquido Folicular/química , Líquido Folicular/metabolismo , Proteômica , Biomarcadores/metabolismo , Lipídeos
20.
Cardiovasc Diabetol ; 23(1): 86, 2024 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-38419039

RESUMO

BACKGROUND: Studies on the relationship between insulin resistance (IR) surrogates and long-term all-cause mortality in patients with coronary heart disease (CHD) and hypertension are lacking. This study aimed to explore the relationship between different IR surrogates and all-cause mortality and identify valuable predictors of survival status in this population. METHODS: The data came from the National Health and Nutrition Examination Survey (NHANES 2001-2018) and National Death Index (NDI). Multivariate Cox regression and restricted cubic splines (RCS) were performed to evaluate the relationship between homeostatic model assessment of IR (HOMA-IR), triglyceride glucose index (TyG index), triglyceride glucose-body mass index (TyG-BMI index) and all-cause mortality. The recursive algorithm was conducted to calculate inflection points when segmenting effects were found. Then, segmented Kaplan-Meier analysis, LogRank tests, and multivariable Cox regression were carried out. Receiver operating characteristic (ROC) and calibration curves were drawn to evaluate the differentiation and accuracy of IR surrogates in predicting the all-cause mortality. Stratified analysis and interaction tests were conducted according to age, gender, diabetes, cancer, hypoglycemic and lipid-lowering drug use. RESULTS: 1126 participants were included in the study. During the median follow-up of 76 months, 455 participants died. RCS showed that HOMA-IR had a segmented effect on all-cause mortality. 3.59 was a statistically significant inflection point. When the HOMA-IR was less than 3.59, it was negatively associated with all-cause mortality [HR = 0.87,95%CI (0.78, 0.97)]. Conversely, when the HOMA-IR was greater than 3.59, it was positively associated with all-cause mortality [HR = 1.03,95%CI (1.00, 1.05)]. ROC and calibration curves indicated that HOMA-IR was a reliable predictor of survival status (area under curve = 0,812). No interactions between HOMA-IR and stratified variables were found. CONCLUSION: The relationship between HOMA-IR and all-cause mortality was U-shaped in patients with CHD and hypertension. HOMA-IR was a reliable predictor of all-cause mortality in this population.


Assuntos
Doença das Coronárias , Hipertensão , Resistência à Insulina , Humanos , Estudos Longitudinais , Inquéritos Nutricionais , Glicemia , Estudos de Coortes , Hipertensão/diagnóstico , Doença das Coronárias/diagnóstico , Triglicerídeos , Glucose , Biomarcadores
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