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2.
Nucleic Acids Res ; 52(5): 2142-2156, 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38340342

RESUMO

Human DNA topoisomerase 1 (Top1) is a crucial enzyme responsible for alleviating torsional stress on DNA during transcription and replication, thereby maintaining genome stability. Previous researches had found that non-working Top1 interacted extensively with chromosomal DNA in human cells. However, the reason for its retention on chromosomal DNA remained unclear. In this study, we discovered a close association between Top1 and chromosomal DNA, specifically linked to the presence of G-quadruplex (G4) structures. G4 structures, formed during transcription, trap Top1 and hinder its ability to relax neighboring DNAs. Disruption of the Top1-G4 interaction using G4 ligand relieved the inhibitory effect of G4 on Top1 activity, resulting in a further reduction of R-loop levels in cells. Additionally, the activation of Top1 through the use of a G4 ligand enhanced the toxicity of Top1 inhibitors towards cancer cells. Our study uncovers a negative regulation mechanism of human Top1 and highlights a novel pathway for activating Top1.


Assuntos
DNA Topoisomerases Tipo I , Quadruplex G , Transcrição Gênica , Humanos , DNA/química , Replicação do DNA , DNA Topoisomerases Tipo I/metabolismo , Ligantes , Inibidores da Topoisomerase I/farmacologia
3.
Hum Genomics ; 18(1): 55, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38822443

RESUMO

BACKGROUND: Although CDKN2A alteration has been explored as a favorable factor for tumorigenesis in pan-cancers, the association between CDKN2A point mutation (MUT) and intragenic deletion (DEL) and response to immune checkpoint inhibitors (ICIs) is still disputed. This study aims to determine the associations of CDKN2A MUT and DEL with overall survival (OS) and response to immune checkpoint inhibitors treatment (ICIs) among pan-cancers and the clinical features of CDKN2A-altered gastric cancer. METHODS: This study included 45,000 tumor patients that underwent tumor sequencing across 33 cancer types from four cohorts, the MSK-MetTropism, MSK-IMPACT, OrigiMed2020 and TCGA cohorts. Clinical outcomes and genomic factors associated with response to ICIs, including tumor mutational burden, copy number alteration, neoantigen load, microsatellite instability, tumor immune microenvironment and immune-related gene signatures, were collected in pan-cancer. Clinicopathologic features and outcomes were assessed in gastric cancer. Patients were grouped based on the presence of CDKN2A wild type (WT), CDKN2A MUT, CDKN2A DEL and CDKN2A other alteration (ALT). RESULTS: Our research showed that CDKN2A-MUT patients had shorter survival times than CDKN2A-WT patients in the MSK MetTropism and TCGA cohorts, but longer OS in the MSK-IMPACT cohort with ICIs treatment, particularly in patients having metastatic disease. Similar results were observed among pan-cancer patients with CDKN2A DEL and other ALT. Notably, CDKN2A ALT frequency was positively related to tumor-specific objective response rates to ICIs in MSK MetTropism and OrigiMed 2020. Additionally, individuals with esophageal carcinoma or stomach adenocarcinoma who had CDKN2A MUT had poorer OS than patients from the MSK-IMPACT group, but not those with adenocarcinoma. We also found reduced levels of activated NK cells, T cells CD8 and M2 macrophages in tumor tissue from CDKN2A-MUT or DEL pan-cancer patients compared to CDKN2A-WT patients in TCGA cohort. Gastric cancer scRNA-seq data also showed that CDKN2A-ALT cancer contained less CD8 T cells but more exhausted T cells than CDKN2A-WT cancer. A crucial finding of the pathway analysis was the inhibition of three immune-related pathways in the CDKN2A ALT gastric cancer patients, including the interferon alpha response, inflammatory response, and interferon gamma response. CONCLUSIONS: This study illustrates the CDKN2A MUT and DEL were associated with a poor outcome across cancers. CDKN2A ALT, on the other hand, have the potential to be used as a biomarker for choosing patients for ICI treatment, notably in esophageal carcinoma and stomach adenocarcinoma.


Assuntos
Inibidor p16 de Quinase Dependente de Ciclina , Neoplasias Gástricas , Microambiente Tumoral , Humanos , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/imunologia , Inibidor p16 de Quinase Dependente de Ciclina/genética , Microambiente Tumoral/genética , Microambiente Tumoral/imunologia , Masculino , Feminino , Inibidores de Checkpoint Imunológico/uso terapêutico , Pessoa de Meia-Idade , Biomarcadores Tumorais/genética , Idoso , Prognóstico , Variações do Número de Cópias de DNA/genética , Mutação/genética , Instabilidade de Microssatélites
4.
Chem Rev ; 123(16): 9940-9981, 2023 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-37561162

RESUMO

A survey of protein databases indicates that the majority of enzymes exist in oligomeric forms, with about half of those found in the UniProt database being homodimeric. Understanding why many enzymes are in their dimeric form is imperative. Recent developments in experimental and computational techniques have allowed for a deeper comprehension of the cooperative interactions between the subunits of dimeric enzymes. This review aims to succinctly summarize these recent advancements by providing an overview of experimental and theoretical methods, as well as an understanding of cooperativity in substrate binding and the molecular mechanisms of cooperative catalysis within homodimeric enzymes. Focus is set upon the beneficial effects of dimerization and cooperative catalysis. These advancements not only provide essential case studies and theoretical support for comprehending dimeric enzyme catalysis but also serve as a foundation for designing highly efficient catalysts, such as dimeric organic catalysts. Moreover, these developments have significant implications for drug design, as exemplified by Paxlovid, which was designed for the homodimeric main protease of SARS-CoV-2.


Assuntos
COVID-19 , Humanos , SARS-CoV-2 , Polímeros
5.
Nano Lett ; 24(12): 3801-3810, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38477714

RESUMO

The effectiveness of various cancer therapies for solid tumors is substantially limited by the highly hypoxic tumor microenvironment (TME). Here, a microalgae-integrated living hydrogel (ACG gel) is developed to concurrently enhance hypoxia-constrained tumor starvation therapy and immunotherapy. The ACG gel is formed in situ following intratumoral injection of a biohybrid fluid composed of alginate, Chlorella sorokiniana, and glucose oxidase, facilitated by the crossing-linking between divalent ions within tumors and alginate. The microalgae Chlorella sorokiniana embedded in ACG gel generate abundant oxygen through photosynthesis, enhancing glucose oxidase-catalyzed glucose consumption and shifting the TME from immunosuppressive to immunopermissive status, thus reducing the tumor cell energy supply and boosting antitumor immunity. In murine 4T1 tumor models, the ACG gel significantly suppresses tumor growth and effectively prevents postoperative tumor recurrence. This study, leveraging microalgae as natural oxygenerators, provides a versatile and universal strategy for the development of oxygen-dependent tumor therapies.


Assuntos
Chlorella , Microalgas , Neoplasias , Animais , Camundongos , Hidrogéis , Glucose Oxidase , Fotossíntese , Hipóxia , Oxigênio , Imunoterapia , Alginatos , Microambiente Tumoral
6.
Mol Pain ; 20: 17448069241261940, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38818809

RESUMO

This study investigated the ERK pathway of the peripheral nervous system and discovered a gender-specific pattern of ERK activation in the dorsal root ganglion of an acid-induced chronic widespread muscular pain model. We employed a twice acid-induced chronic musculoskeletal pain model in rats to evaluate mechanical pain behavior in both male and female groups. We further conducted protein analysis of dissected dorsal root ganglions from both genders. Both male and female rats exhibited a similar pain behavior trend, with females demonstrating a lower pain threshold. Protein analysis of the dorsal root ganglion (DRG) showed a significant increase in phosphorylated ERK after the second acid injection in all groups. However, phosphorylation of ERK was observed in the dorsal root ganglion, with higher levels in the male ipsilateral group compared to the female group. Moreover, there was a no difference between the left and right sides in males, whereas the significant difference was observed in females. In conclusions, the administration of acid injections induced painful behavior in rats, and concurrent with this, a significant upregulation of pERK was observed in the dorsal root ganglia, with a greater magnitude of increase in males than females, and in the contralateral side compared to the ipsilateral side. Our findings shed light on the peripheral mechanisms underlying chronic pain disorders and offer potential avenues for therapeutic intervention.


Assuntos
MAP Quinases Reguladas por Sinal Extracelular , Fibromialgia , Gânglios Espinais , Ratos Sprague-Dawley , Caracteres Sexuais , Animais , Masculino , Feminino , Fibromialgia/metabolismo , Gânglios Espinais/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Fosforilação/efeitos dos fármacos , Ratos , Limiar da Dor , Modelos Animais de Doenças , Dor/metabolismo , Dor/fisiopatologia
7.
Radiology ; 311(1): e231461, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38652028

RESUMO

Background Noninvasive tests can be used to screen patients with chronic liver disease for advanced liver fibrosis; however, the use of single tests may not be adequate. Purpose To construct sequential clinical algorithms that include a US deep learning (DL) model and compare their ability to predict advanced liver fibrosis with that of other noninvasive tests. Materials and Methods This retrospective study included adult patients with a history of chronic liver disease or unexplained abnormal liver function test results who underwent B-mode US of the liver between January 2014 and September 2022 at three health care facilities. A US-based DL network (FIB-Net) was trained on US images to predict whether the shear-wave elastography (SWE) value was 8.7 kPa or higher, indicative of advanced fibrosis. In the internal and external test sets, a two-step algorithm (Two-step#1) using the Fibrosis-4 Index (FIB-4) followed by FIB-Net and a three-step algorithm (Three-step#1) using FIB-4 followed by FIB-Net and SWE were used to simulate screening scenarios where liver stiffness measurements were not or were available, respectively. Measures of diagnostic accuracy were calculated using liver biopsy as the reference standard and compared between FIB-4, SWE, FIB-Net, and European Association for the Study of the Liver guidelines (ie, FIB-4 followed by SWE), along with sequential algorithms. Results The training, validation, and test data sets included 3067 (median age, 42 years [IQR, 33-53 years]; 2083 male), 1599 (median age, 41 years [IQR, 33-51 years]; 1124 male), and 1228 (median age, 44 years [IQR, 33-55 years]; 741 male) patients, respectively. FIB-Net obtained a noninferior specificity with a margin of 5% (P < .001) compared with SWE (80% vs 82%). The Two-step#1 algorithm showed higher specificity and positive predictive value (PPV) than FIB-4 (specificity, 79% vs 57%; PPV, 44% vs 32%) while reducing unnecessary referrals by 42%. The Three-step#1 algorithm had higher specificity and PPV compared with European Association for the Study of the Liver guidelines (specificity, 94% vs 88%; PPV, 73% vs 64%) while reducing unnecessary referrals by 35%. Conclusion A sequential algorithm combining FIB-4 and a US DL model showed higher diagnostic accuracy and improved referral management for all-cause advanced liver fibrosis compared with FIB-4 or the DL model alone. © RSNA, 2024 Supplemental material is available for this article. See also the editorial by Ghosh in this issue.


Assuntos
Algoritmos , Técnicas de Imagem por Elasticidade , Cirrose Hepática , Humanos , Masculino , Cirrose Hepática/diagnóstico por imagem , Pessoa de Meia-Idade , Feminino , Estudos Retrospectivos , Técnicas de Imagem por Elasticidade/métodos , Adulto , Aprendizado Profundo , Fígado/diagnóstico por imagem , Fígado/patologia , Idoso , Ultrassonografia/métodos
8.
Fish Shellfish Immunol ; 149: 109614, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38710342

RESUMO

Chemokines are critical molecules involved in immune reaction and immune system homeostasis, and some chemokines play a role in antiviral immunity. It is not known if the C-C motif chemokine ligand 3 (CCL3), a member of the CC chemokine family, possesses antiviral properties in fish. In this study, a ccl3 was cloned from the mandarin fish (Siniperca chuatsi), and it has an open reading frame (ORF) of 276 base pairs, which are predicted to encode a 91-amino acid peptide. Mandarin fish CCL3 revealed conserved sequence features with four cysteine residues and closely relationships with the CCL3s from other vertebrates based on the sequence alignment and phylogenetic analysis. The transcripts of ccl3 were notably enriched in immune-related organs, such as spleen and gills in healthy mandarin fish, and the ccl3 was induced in the isolated mandarin fish brain (MFB) cells following infection with infectious spleen and kidney necrosis virus (ISKNV). Moreover, in MFB cells, overexpression of CCL3 induced immune factors, such as IL1ß, TNFα, MX, IRF1 and IFNh, and exhibited antiviral activity against ISKNV. This study sheds light on the immune role of CCL3 in immune response of mandarin fish, and its antiviral defense mechanism is of interest for further investigation.


Assuntos
Sequência de Aminoácidos , Infecções por Vírus de DNA , Doenças dos Peixes , Proteínas de Peixes , Imunidade Inata , Iridoviridae , Perciformes , Filogenia , Alinhamento de Sequência , Animais , Proteínas de Peixes/genética , Proteínas de Peixes/imunologia , Proteínas de Peixes/química , Doenças dos Peixes/imunologia , Doenças dos Peixes/virologia , Perciformes/imunologia , Perciformes/genética , Infecções por Vírus de DNA/imunologia , Infecções por Vírus de DNA/veterinária , Iridoviridae/fisiologia , Alinhamento de Sequência/veterinária , Imunidade Inata/genética , Regulação da Expressão Gênica/imunologia , Quimiocina CCL3/genética , Quimiocina CCL3/imunologia , Clonagem Molecular , Perfilação da Expressão Gênica/veterinária , Sequência de Bases
9.
Org Biomol Chem ; 22(10): 2021-2026, 2024 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-38372990

RESUMO

cis-Zeatin (cZ), a cytokinin often overlooked compared to trans-zeatin (tZ), can now be controlled in live cells and plants through a new biocompatible reaction. Using flavin photosensitizers, cZ can be isomerized to tZ or degraded, depending on the presence of a reducing reagent. This breakthrough offers a novel approach for regulating plant growth through chemical molecules.


Assuntos
Mononucleotídeo de Flavina , Zeatina , Zeatina/química , Zeatina/metabolismo , Mononucleotídeo de Flavina/metabolismo , Isomerismo , Citocininas
10.
Phys Chem Chem Phys ; 26(4): 3500-3515, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38206084

RESUMO

Polymorphic transformation of molecular crystals is a fundamental phase transition process, and it is important practically in the chemical, material, biopharmaceutical, and energy storage industries. However, understanding of the transformation mechanism at the molecular level is poor due to the extreme simulating challenges in enhanced sampling and formulating order parameters (OPs) as the collective variables that can distinguish polymorphs with quite similar and complicated structures so as to describe the reaction coordinate. In this work, two kinds of OPs for CL-20 were constructed by the bond distances, bond orientations and relative orientations. A K-means clustering algorithm based on the Euclidean distance and sample weight was used to smooth the initial finite temperature string (FTS), and the minimum free energy path connecting ß-CL-20 and ε-CL-20 was sketched by the string method in collective variables, and the free energy profile along the path and the nucleation kinetics were obtained by Markovian milestoning with Voronoi tessellations. In comparison with the average-based sampling, the K-means clustering algorithm provided an improved convergence rate of FTS. The simulation of transformation was independent of OP types but was affected greatly by finite-size effects. A surface-mediated local nucleation mechanism was confirmed and the configuration located at the shoulder of potential of mean force, rather than overall maximum, was confirmed to be the critical nucleus formed by the cooperative effect of the intermolecular interactions. This work provides an effective way to explore the polymorphic transformation of caged molecular crystals at the molecular level.

11.
Artif Organs ; 48(5): 504-513, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38146899

RESUMO

BACKGROUND: A percutaneous ventricular assist device (pVAD) is an effective method to treat heart failure, but its complications, mainly hemolysis and thrombus formation, cannot be ignored. Accurate evaluation of hemolysis and thrombus formation in pVAD is essential to guide the development of pVAD and reduce the incidence of complications. METHODS: This study optimized the numerical model to predict hemolysis and thrombus formation in pVAD. The hemolysis model is based on the power law function, and the multi-component thrombus prediction model is improved by introducing the von Willebrand factor. RESULTS: The error between the numerical simulation and the hydraulic performance experiment is within 5%. The numerical results of hemolysis are in good agreement with those of in vitro experiments. Meanwhile, the thrombus location predicted by the numerical model is the same as that found in the in vivo experiment. CONCLUSION: The numerical model suggested in this study may therefore accurately assess the possible hemolytic and thrombotic dangers in pVAD, making it an effective tool to support the development of pVAD.


Assuntos
Insuficiência Cardíaca , Coração Auxiliar , Trombose , Humanos , Hemólise , Coração Auxiliar/efeitos adversos , Insuficiência Cardíaca/cirurgia , Simulação por Computador , Trombose/etiologia
12.
Langenbecks Arch Surg ; 409(1): 154, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38714551

RESUMO

BACKGROUND: In recent years, there has been an increasing prevalence of patients with papillary thyroid microcarcinoma (PTMC) without lymph node involvement in medical centers worldwide. For patients who are unable to undergo active surveillance (AS) and are afraid of postoperative complications, conformal thyroidectomy may be a suitable option to ensure both preservation of function and complete removal of the tumor. METHODS: The patients in the cohort during 2010 to 2015 were retrospectively enrolled strictly following the inclusion and exclusion criteria. The observation and control groups were defined based on the surgical approach, with patients in the observation group undergoing conformal thyroidectomy and patients in the control group undergoing lobectomy. Event-free survival (EFS), the interval from initial surgery to the detection of recurrent or metastatic disease, was defined as the primary observation endpoint. RESULTS: A total of 319 patients were included in the study, with 124 patients undergoing conformal thyroidectomy and 195 patients undergoing lobectomy. When compared to lobectomy, conformal thyroidectomy demonstrated reduced hospital stays, shorter operative times, and lower rates of vocal cord paralysis and hypoparathyroidism. Furthermore, the mean bleeding volume during the operation and the rate of permanent hypothyroidism were also lower in the conformal thyroidectomy group than in the lobectomy group. However, there was no statistically significant difference observed in the 5- and 10-year EFS between the two groups. CONCLUSIONS: Conformal thyroidectomy had advantages in perioperative management and short-term complication rates, with an EFS that was not inferior to that of lobectomy. Thus, conformal thyroidectomy is a feasible option for low-risk PTMC patients.


Assuntos
Carcinoma Papilar , Neoplasias da Glândula Tireoide , Tireoidectomia , Humanos , Tireoidectomia/métodos , Tireoidectomia/efeitos adversos , Feminino , Masculino , Neoplasias da Glândula Tireoide/cirurgia , Neoplasias da Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/mortalidade , Estudos Retrospectivos , Pessoa de Meia-Idade , Carcinoma Papilar/cirurgia , Carcinoma Papilar/patologia , Carcinoma Papilar/mortalidade , Adulto , Seguimentos , Estudos de Viabilidade , Estudos de Coortes , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Resultado do Tratamento , Duração da Cirurgia
13.
BMC Musculoskelet Disord ; 25(1): 377, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38741113

RESUMO

BACKGROUND: Periprosthetic joint infection (PJI) is a severe complication that can occur after total joint arthroplasty (TJA). The timely and accurate diagnosis of PJI is the key to treatment. This study investigated the diagnostic value of platelet to lymphocyte ratio (PLR), platelet count to mean platelet volume ratio (PVR), neutrophil to lymphocyte ratio (NLR) and monocyte to lymphocyte ratio (MLR) in PJI after total knee arthroplasty (TKA) and total hip arthroplasty (THA). METHODS: We performed a retrospective analysis of the patients who underwent revision hip or knee arthroplasty at our Institute between June 2015 and June 2020. Of the 187 patients reviewed, 168 were included in the study. According to the diagnostic criteria of the Musculoskeletal Infection Society (MSIS), 58 patients were in the PJI group, and 110 patients were in the aseptic loosening (AL) group. We recorded and compared the preoperative peripheral blood white blood cell (WBC) count, platelet count (PLT), erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), PLR, PVR, NLR, and MLR in both groups. The diagnostic performance of the WBC, PLT, PLR, PVR, NLR, and MLR individually and in combination with the ESR and CRP for PJI diagnosis was evaluated by receiver operating characteristic (ROC) curves, and the sensitivity, specificity, positive predictive value, and negative predictive value were calculated. RESULTS: Compared to those in the AL group, the mean WBC, PLT, ESR, CRP, PLR, PVR, NLR, and MLR in the peripheral blood of the PJI group were significantly greater (P < 0.05). The analysis of the ROC curve revealed that the ESR, CRP, PLR, PVR, NLR, and MLR in peripheral blood had moderate effectiveness in diagnosing PJI, with area under the curve (AUC) values of 0.760 (95% CI: 0.688-0.823), 0.758 (95% CI: 0.687-0.821), 0.714 (95% CI: 0.639-0.781), 0.709 (95% CI: 0.634-0.777), 0.723 (95% CI: 0.649-0.789), and 0.728 (95% CI: 0.654-0.793), respectively. Conversely, the WBC and PLT counts demonstrated poor diagnostic value for PJI, with AUC values of 0.578 (95% CI: 0.499-0.653) and 0.694 (95% CI: 0.619-0.763), respectively. The results of the prediction model calculations revealed that the combined AUC of the WBC, PLT, ESR, CRP, PLR, PVR, NLR, and MLR was the highest at 0.853 (95% CI, 0.790-0.909), indicating good value in the diagnosis of PJI, with a sensitivity of 82.8% and a specificity of 72.7%. Moreover, the novel composite of parameters improved the accuracy and reliability in diagnosing PJI compared to the traditional biomarkers ESR and CRP (P = 0.015). CONCLUSION: Our study suggested that the diagnostic value of the peripheral blood biomarkers PLR, PVR, NLR, and MLR for diagnosing PJI is limited and not superior to that of the ESR or CRP. However, when the WBC, PLT, ESR, CRP, PLR, PVR, NLR, and MLR are combined, the diagnostic performance of PJI in TJA patients can be improved.


Assuntos
Artroplastia de Quadril , Artroplastia do Joelho , Biomarcadores , Infecções Relacionadas à Prótese , Humanos , Estudos Retrospectivos , Feminino , Masculino , Idoso , Pessoa de Meia-Idade , Infecções Relacionadas à Prótese/diagnóstico , Infecções Relacionadas à Prótese/sangue , Infecções Relacionadas à Prótese/etiologia , Artroplastia do Joelho/efeitos adversos , Artroplastia de Quadril/efeitos adversos , Biomarcadores/sangue , Contagem de Plaquetas , Proteína C-Reativa/análise , Contagem de Leucócitos , Sedimentação Sanguínea , Neutrófilos , Contagem de Linfócitos , Volume Plaquetário Médio , Idoso de 80 Anos ou mais , Valor Preditivo dos Testes , Curva ROC
14.
Proc Natl Acad Sci U S A ; 118(21)2021 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-34001600

RESUMO

G-quadruplexes (G4s) formed by guanine-rich nucleic acids play a role in essential biological processes such as transcription and replication. Besides the >1.5 million putative G-4-forming sequences (PQSs), the human genome features >640 million single-nucleotide variations (SNVs), the most common type of genetic variation among people or populations. An SNV may alter a G4 structure when it falls within a PQS motif. To date, genome-wide PQS-SNV interactions and their impact have not been investigated. Herein, we present a study on the PQS-SNV interactions and the impact they can bring to G4 structures and, subsequently, gene expressions. Based on build 154 of the Single Nucleotide Polymorphism Database (dbSNP), we identified 5 million gains/losses or structural conversions of G4s that can be caused by the SNVs. Of these G4 variations (G4Vs), 3.4 million are within genes, resulting in an average load of >120 G4Vs per gene, preferentially enriched near the transcription start site. Moreover, >80% of the G4Vs overlap with transcription factor-binding sites and >14% with enhancers, giving an average load of 3 and 7.5 for the two regulatory elements, respectively. Our experiments show that such G4Vs can significantly influence the expression of their host genes. These results reveal genome-wide G4Vs and their impact on gene activity, emphasizing an understanding of genetic variation, from a structural perspective, of their physiological function and pathological implications. The G4Vs may also provide a unique category of drug targets for individualized therapeutics, health risk assessment, and drug development.


Assuntos
Proteínas de Ligação a DNA/ultraestrutura , Quadruplex G , Genoma Humano/genética , Conformação de Ácido Nucleico , Proteínas de Ligação a DNA/genética , Regulação da Expressão Gênica/genética , Humanos , Polimorfismo de Nucleotídeo Único/genética , Regiões Promotoras Genéticas/genética , Ligação Proteica/genética , Sequências Reguladoras de Ácido Nucleico/genética , Sítio de Iniciação de Transcrição , Ativação Transcricional/genética
15.
Ecotoxicol Environ Saf ; 273: 116117, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38377780

RESUMO

Field rapid determination of soil accessible Cr(Ⅵ) is of great significance for on-site assessment and decision-making about the health risks of contaminated sites. When the thickness of solutions with various concentrations of Cr(Ⅵ) is constant, there would be a quantitative relationship between the chromogenic difference of Cr(Ⅵ) solutions and the concentration of Cr(Ⅵ). The chromogenic difference could be described by Red (R), Green (G), Blue (B) values. Based on the chromogenic reaction between 1,5-diphenylcarbazide and Cr(Ⅵ), this study first established the calibration curve between the chromogenic difference and the concentration of Cr(Ⅵ) in standard solution with or without 0.01 M CaCl2, using an RGB color sensor. This is the subsequent determination basis of the method for rapidly assessing accessible Cr(Ⅵ) in the field (M-RGB). Then, the concentration of accessible Cr(Ⅵ) of contaminated soil with "hand-shaking + standing" field extraction method was compared with "end-over-end shaking" laboratory extraction method. Finally, the accessible Cr(Ⅵ) of contaminated soil extractants was determined via M-RGB integrating the field extraction method. Results indicated there was a highly significant linear relationship between colorimetric difference value (∆E) and Cr(Ⅵ) concentration in the range of 0.1-3 mg/L (R2 > 0.99, P < 0.01), based on the Euclidean formula for calculating ∆E. The "hand-shaking + standing" field extraction method was effective in obtaining accessible Cr(Ⅵ) extractants with or without 0.01 M CaCl2, with the high extraction efficiency within 100±1%. The concentrations of accessible Cr(Ⅵ) in various polluted soils determined by M-RGB were consistent with that determined by the ultraviolet-visible spectrophotometry, with the relative error within ±5%, and the relative standard deviation ≤ 20%. The spiked recovery experiments showed that the recovery of M-RGB was between 95% and 105%, which means M-RGB could realize the trace analysis for accessible Cr(Ⅵ) in the field.


Assuntos
Cromo , Solo , Cloreto de Cálcio , Cromo/análise , Poluição Ambiental/análise
16.
Chem Biodivers ; 21(3): e202301315, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38189169

RESUMO

Thousands of years ago, humans started to use propolis because of its medicinal properties, and modern science has successfully identified several bioactive molecules within this resinous bee product. However, a natural propolis extract which has been removed the adhesive glue and preserved propolis bioactive compounds is urgently needed to maximise the therapeutic opportunities. In this study, a novel ultrafiltrate fraction from Brazilian green propolis, termed P30K, was demonstrated with anti-inflammatory properties, both in vitro and in vivo. Total flavonoids and total phenolic acids content in P30K were 244.6 mg/g and 275.8 mg/g respectively, while the IC50 value of inhibition of cyclooxygenase-2 (COX-2) was 8.30 µg/mL. The anti-inflammatory activity of P30K was furtherly corroborated in experimental models of lipopolysaccharides (LPS)-induced acute liver and lung injury. Mechanistically, integrated GC-MS and LC-MS based serum metabolomics analysis revealed that P30K modulated citrate cycle (TCA), pyruvate, glyoxylate and dicarboxylate metabolism pathways to inhibit secretion of pro-inflammatory cytokines. Results of network pharmacology and molecular docking suggested that P30K targeted catechol-O-methyltransferases (COMT), 11ß-hydroxysteroid dehydrogenases (HSD11B1), and monoamine oxidases (MAOA and MAOB) to promote cellular metabolomic rewiring. Collectively, our work reveals P30K as an efficient therapeutic agent against inflammatory conditions and its efficacy is related to metabolic rewiring.


Assuntos
Própole , Humanos , Própole/farmacologia , Simulação de Acoplamento Molecular , Flavonoides/farmacologia , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Brasil
17.
Zhongguo Zhong Yao Za Zhi ; 49(4): 1073-1081, 2024 Feb.
Artigo em Zh | MEDLINE | ID: mdl-38621914

RESUMO

The present study aimed to investigate the effect and mechanism of Bupleuri Radix-Paeoniae Radix Alba medicated plasma on HepG2 hepatoma cells by regulating the microRNA-1297(miR-1297)/phosphatase and tensin homologue deleted on chromosome 10(PTEN) signaling axis. Real-time quantitative PCR(RT-qPCR) was carried out to determine the mRNA levels of miR-1297 and PTEN in different hepatoma cell lines. The dual luciferase reporter assay was employed to verify the targeted interaction between miR-1297 and PTEN. The cell counting kit-8(CCK-8) was used to detect cell proliferation, and the optimal concentration and intervention time of the medicated plasma were determined. The cell invasion and migration were examined by Transwell assay and wound healing assay. Cell cycle distribution was detected by PI staining, and the apoptosis of cells was detected by Annexin V-FITC/PI double staining. The mRNA levels of miR-1297, PTEN, protein kinase B(Akt), and phosphatidylinositol 3-kinase(PI3K) were determined by RT-qPCR. Western blot was employed to determine the protein levels of PTEN, Akt, p-Akt, caspase-3, caspase-9, B-cell lymphoma-2(Bcl-2), and Bcl-2-associated X protein(Bax). The results showed that HepG2 cells were the best cell line for subsequent experiments. The dual luciferase reporter assay confirmed that miR-1297 could bind to the 3'-untranslated region(3'UTR) in the mRNA of PTEN. The medicated plasma inhibited the proliferation of HepG2 cells, and the optimal intervention concentration and time were 20% and 72 h. Compared with the blank plasma, the Bupleuri Radix-Paeoniae Radix Alba medicated plasma, miR-1297 inhibitor, miR-1297 inhibitor + medicated plasma all inhibited the proliferation, invasion, and migration of HepG2 cells, increased the proportion of cells in the G_0/G_1 phase, decreased the proportion of cells in the S phase, and increased the apoptosis rate. The medicated plasma down-regulated the mRNA levels of miR-1297, PI3K, and Akt and up-regulated the mRNA level of PTEN. In addition, it up-regulated the protein levels of PTEN, Bax, caspase-3, and caspsae-9 and down-regulated the protein levels of p-Akt, p-PI3K, and Bcl-2. In conclusion, Bupleuri Radix-Paeoniae Radix Alba medicated plasma can inhibit the expression of miR-1297 in HepG2 hepatoma cells, promote the expression of PTEN, and negatively regulate PI3K/Akt signaling pathway, thereby inhibiting the proliferation and inducing the apoptosis of HepG2 cells.


Assuntos
Carcinoma Hepatocelular , Medicamentos de Ervas Chinesas , Neoplasias Hepáticas , MicroRNAs , Paeonia , Extratos Vegetais , Humanos , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Células Hep G2 , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/genética , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Caspase 3/metabolismo , Proteína X Associada a bcl-2 , MicroRNAs/genética , MicroRNAs/metabolismo , Transdução de Sinais , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/genética , Apoptose , Proliferação de Células , PTEN Fosfo-Hidrolase/genética , PTEN Fosfo-Hidrolase/metabolismo , RNA Mensageiro , Luciferases/metabolismo , Luciferases/farmacologia , Linhagem Celular Tumoral
18.
Eur J Neurosci ; 58(3): 2807-2823, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37452644

RESUMO

The bed nucleus of the stria terminalis (BNST) is a neuropeptide-enriched brain region that modulates a wide variety of emotional behaviours and states, including stress, anxiety, reward and social interaction. The BNST consists of diverse subregions and neuronal ensembles; however, because of the high molecular heterogeneity within BNST neurons, the mechanisms through which the BNST regulates distinct emotional behaviours remain largely unclear. Prior studies have identified BNST calretinin (CR)-expressing neurons, which lack neuropeptides. Here, employing virus-based cell-type-specific retrograde and anterograde tracing systems, we mapped the whole-brain monosynaptic inputs and axonal projections of BNST CR-expressing neurons in male mice. We found that BNST CR-expressing neurons received inputs mainly from the amygdalopiriform transition area, central amygdala and hippocampus and moderately from the medial preoptic area, basolateral amygdala, paraventricular thalamus and lateral hypothalamus. Within the BNST, plenty of input neurons were primarily located in the oval and interfascicular subregions. Furthermore, numerous BNST CR-expressing neuronal boutons were observed within the BNST but not in other brain regions, thus suggesting that these neurons are a type of interneuron. These results will help further elucidate the neuronal circuits underlying the elaborate and distinct functions of the BNST.


Assuntos
Neuropeptídeos , Núcleos Septais , Camundongos , Masculino , Animais , Núcleos Septais/metabolismo , Calbindina 2 , Encéfalo/metabolismo , Neuropeptídeos/metabolismo , Interneurônios/metabolismo
19.
J Transl Med ; 21(1): 20, 2023 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-36635710

RESUMO

Recent studies have identified DNA replication stress as an important feature of advanced prostate cancer (PCa). The identification of biomarkers for DNA replication stress could therefore facilitate risk stratification and help inform treatment options for PCa. Here, we designed a robust machine learning-based framework to comprehensively explore the impact of DNA replication stress on prognosis and treatment in 5 PCa bulk transcriptomic cohorts with a total of 905 patients. Bootstrap resampling-based univariate Cox regression and Boruta algorithm were applied to select a subset of DNA replication stress genes that were more clinically relevant. Next, we benchmarked 7 survival-related machine-learning algorithms for PCa recurrence using nested cross-validation. Multi-omic and drug sensitivity data were also utilized to characterize PCa with various DNA replication stress. We found that the hyperparameter-tuned eXtreme Gradient Boosting model outperformed other tuned models and was therefore used to establish a robust replication stress signature (RSS). RSS demonstrated superior performance over most clinical features and other PCa signatures in predicting PCa recurrence across cohorts. Lower RSS was characterized by enriched metabolism pathways, high androgen activity, and a favorable prognosis. In contrast, higher RSS was significantly associated with TP53, RB1, and PTEN deletion, exhibited increased proliferation and DNA replication stress, and was more immune-suppressive with a higher chance of immunotherapy response. In silico screening identified 13 potential targets (e.g. TOP2A, CDK9, and RRM2) from 2249 druggable targets, and 2 therapeutic agents (irinotecan and topotecan) for RSS-high patients. Additionally, RSS-high patients were more responsive to taxane-based chemotherapy and Poly (ADP-ribose) polymerase inhibitors, whereas RSS-low patients were more sensitive to androgen deprivation therapy. In conclusion, a robust machine-learning framework was used to reveal the great potential of RSS for personalized risk stratification and therapeutic implications in PCa.


Assuntos
Neoplasias da Próstata , Masculino , Humanos , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Androgênios , Antagonistas de Androgênios/uso terapêutico , Aprendizado de Máquina , Replicação do DNA
20.
Opt Express ; 31(17): 27266-27273, 2023 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-37710805

RESUMO

Optical power splitters (OPSs) have been widely used in photonic integrated circuits, but an OPS with a large fabrication tolerance and free choice of power splitting ratio (PSR) is still highly desired for thin-film lithium niobate (TFLN) platform. Here, we propose and experimentally demonstrate several 1 × 2 OPSs with PSRs from 50:50 to 5:95 using TFLN platform. The proposed devices are built by multimode interference structure to achieve a broad bandwidth and large fabrication tolerance. Various PSRs can be obtained by adjusting the geometry structure of the multimode interference region. All of our fabricated devices feature an insertion loss lower than 0.3 dB at the wavelength of 1550 nm, and a PSR variation less than 3% in the range of 1520 nm to 1590 nm.

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