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1.
FASEB J ; 38(10): e23682, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38780524

RESUMO

Gliomas are highly vascularized malignancies, but current anti-angiogenic treatments have not demonstrated practical improvements in patient survival. Studies have suggested that glioma-derived endothelial cell (GdEC) formed by glioma stem cell (GSC) differentiation may contribute to the failure of this treatment. However, the molecular mechanisms involved in GSC endothelial differentiation remain poorly understood. We previously reported that vasorin (VASN) is highly expressed in glioma and promotes angiogenesis. Here, we show that VASN expression positively correlates with GdEC signatures in glioma patients. VASN promotes the endothelial differentiation capacity of GSC in vitro and participates in the formation of GSC-derived vessels in vivo. Mechanistically, vascular endothelial growth factor receptor 2 (VEGFR2) is a critical factor that mediates the regulation of VASN on GSC endothelial differentiation. Separation of cell chromatin fractionation and chromatin immunoprecipitation-sequencing analysis show that VASN interacts with Notch1 and co-translocates into the cell nuclei, where VASN binds to the VEGFR2 gene promoter to stimulate its transcription during the progression of GSC differentiation into GdEC. Together, these findings elucidate the role and mechanisms of VASN in promoting the endothelial differentiation of GSC and suggest VASN as a potential target for anti-angiogenic therapy based on intervention in GdEC formation in gliomas.


Assuntos
Diferenciação Celular , Células Endoteliais , Glioma , Proteínas de Membrana , Células-Tronco Neoplásicas , Receptor 2 de Fatores de Crescimento do Endotélio Vascular , Animais , Humanos , Camundongos , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/genética , Linhagem Celular Tumoral , Células Endoteliais/metabolismo , Regulação Neoplásica da Expressão Gênica , Glioma/metabolismo , Glioma/patologia , Glioma/genética , Camundongos Nus , Proteínas dos Microfilamentos/metabolismo , Proteínas dos Microfilamentos/genética , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Neovascularização Patológica/metabolismo , Neovascularização Patológica/genética , Transcrição Gênica , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/genética , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo
2.
Semin Cell Dev Biol ; 121: 63-70, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34001436

RESUMO

Stem cells are specialized cells that can renew themselves through cell division and can differentiate into multi-lineage cells. Mesenchymal stem cells are adult stem cells that exist in animal and human tissues. Mesenchymal stem cells have the ability to differentiate into mesodermal lineages, such as Leydig cells, adipocytes, osteocytes, and chondrocytes. Mesenchymal stem cells express cell surface markers, such as cluster of differentiation (CD) 29, CD44, CD73, CD90, CD105, and lack the expression of CD14, CD34, CD45 and HLA (human leukocyte antigen)-DR. Stem Leydig cells are one kind of mesenchymal stem cells, which are present in the interstitial compartment of testis. Stem Leydig cells are multipotent and can differentiate into Leydig cells, adipocytes, osteocytes, and chondrocytes. Stem Leydig cells have been isolated from rodent and human testes. Stem Leydig cells may have potential therapeutic values in several clinical applications, such as the treatment of male hypogonadism and infertility. In this review, we focus on the latest research on stem Leydig cells of both rodents and human, the expression of cell surface markers, culture, differentiation potential, and their applications.


Assuntos
Células Intersticiais do Testículo/metabolismo , Medicina Regenerativa/métodos , Saúde Reprodutiva/normas , Animais , Humanos , Masculino , Camundongos , Ratos
3.
Rheumatology (Oxford) ; 63(1): 235-241, 2024 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-37184876

RESUMO

OBJECTIVES: To explore the relationship of tumour-associated antigens (TAAs) with the clinical manifestations and serological markers of SLE. METHODS: This was a retrospective study. Clinical data of SLE patients were extracted from the electronic medical records, including serum levels of TAAs such as alpha-fetoprotein (AFP), carcinoembryonic antigen (CEA), cancer antigen (CA) 19-9, CA125, CA15-3 and cytokeratin 19-fragments (CYFRA21-1). TAA positivity was defined as serum level exceeding the upper limit of the corresponding reference range. RESULTS: A total of 149 SLE patients (SLE group) and 149 age- and sex-matched healthy subjects (control group) were enrolled. Compared with healthy controls, the SLE group had higher positivity rates for CA19-9 and CYFRA21-1, and elevated serum levels of CA125, CA15-3 and CYFRA21-1. SLE patients with TAA positivity were older, had a higher prevalence of serous effusion, pericardial effusion, albuminuria and thrombocytopenia, and lower positivity rate for anti-dsDNA than patients without TAA positivity. The levels of serum creatinine (SCR), blood urea nitrogen, glutamic oxalate transaminase and 24-h urinary protein were also higher in SLE patients with TAA positivity, but platelet count and serum albumin levels were lower. On logistic regression, thrombocytopenia and SCR levels were identified as independent risk factors for TAA positivity. CA125 positivity rate and serum levels of CA125 were associated with SLE disease activity. CONCLUSION: The positivity rates and serum levels of some TAAs were elevated in SLE, and thrombocytopenia and SCR levels were independent risk factors for TAA positivity.


Assuntos
Lúpus Eritematoso Sistêmico , Neoplasias , Trombocitopenia , Humanos , Biomarcadores Tumorais , Antígeno Ca-125/metabolismo , Estudos Retrospectivos , Antígeno CA-19-9 , Mucina-1
4.
Opt Express ; 32(5): 7171-7184, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38439405

RESUMO

We propose an efficient method for calculating the electromagnetic field of a large-scale array of optical nanoresonators based on the coupling theory of quasinormal mode (QNM). In this method, two approaches of the scattered-field reconstruction and stationary-phase-principle calculated plane-wave expansion are developed to obtain the regularized QNM (RQNM) in different regions. This accurate and efficient calculation of RQNM resolves the far-field divergence issue of QNMs in the QNM-coupling theory, thus enabling a rapid computation of the electromagnetic field of a large-scale array of optical nanoresonators, which is a challenging task for full-wave numerical methods. Using this method, we consider the numerical example of the radiation problem of a single point source in a large-scale periodic array of optical nanoantennas. In comparison to full-wave numerical methods, this method significantly reduces the computation time by 1∼2 orders of magnitude while maintaining accuracy. The high computational efficiency and physical intuitiveness of the method enables to clarify the impact of array size (exceeding 50 × 50 wavelengths), period and field-coupling range (far beyond the tight-binding approximation) on the optical response. The proposed method and results can provide an efficient tool and guidance for the design of large-scale arrays of optical nanoresonators.

5.
Microb Pathog ; 195: 106900, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39208964

RESUMO

Campylobacter jejuni (C. jejuni) is a major cause of gastroenteritis and rarely cause bloodstream infection. Herein, we characterized a multidrug-resistant C. jejuni strain LZCJ isolated from a tumor patient with bloodstream infection. LZCJ was resistant to norfloxacin, ampicillin, ceftriaxone, ciprofloxacin and tetracycline. It showed high survival rate in serum and acidic environment. Whole genome sequencing (WGS) analysis revealed that strain LZCJ had a single chromosome of 1,629,078 bp (30.6 % G + C content) and belonged to the ST137 lineage. LZCJ shared the highest identity of 99.66 % with the chicken-derived C. jejuni MTVDSCj20. Four antimicrobial resistance genes (ARGs) were detected, blaOXA-61, tet(O), gyrA (T86I), and cmeR (G144D and S207G). In addition, a 12,746 bp genomic island GI_LZCJ carrying 15 open reading frames (ORFs) including the resistance gene tet(O) was identified. Sequence analysis found that the GI_LZCJ was highly similar to the duck-derived C. jejuni ZS004, but with an additional ISChh1-like sequence. 137 non-synonymous mutations in motility related genes (flgF, fapR, flgS), capsular polysaccharide (CPS) coding genes (kpsE, kpsF, kpsM, kpsT), metabolism associated genes (nuoF, nuoG, epsJ, holB), and transporter related genes (comEA, gene0911) were confirmed in LZCJ compared with the best closed chicken-derived strain MTVDSCj20. Our study showed that C. jejuni strain LZCJ was highly similar to the chicken-derived strain MTVDSCj20 but with a lot of SNPs involved in motility, CPS and metabolism coding genes. This strain possessed a tet(O)-positive genomic island GI_LZCJ, which was closed to duck-derived C. jejuni ZS004, but with an additional ISChh1-like sequence. The above data indicated that the LZCJ strain may originate from foodborne bacteria on animals and the importance of continuous surveillance for the spread of foodborne bacteria.


Assuntos
Antibacterianos , Proteínas de Bactérias , Infecções por Campylobacter , Campylobacter jejuni , Farmacorresistência Bacteriana Múltipla , Ilhas Genômicas , Testes de Sensibilidade Microbiana , Sequenciamento Completo do Genoma , Campylobacter jejuni/genética , Campylobacter jejuni/efeitos dos fármacos , Campylobacter jejuni/isolamento & purificação , Farmacorresistência Bacteriana Múltipla/genética , Humanos , Ilhas Genômicas/genética , Infecções por Campylobacter/microbiologia , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Genoma Bacteriano , Composição de Bases , Bacteriemia/microbiologia , Animais , Filogenia , Fases de Leitura Aberta , Proteínas de Transporte
6.
Opt Lett ; 49(18): 5147-5150, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-39270251

RESUMO

We investigate the temperature tunable dual quasi-bound states in the continuum (qBICs) in a silicon/vanadium dioxide (Si/VO2) hybrid metasurface with Q-factor being as large as 9.3 × 106 and 2.8 × 107 by breaking the in-plane C2 symmetry. The far-field scattering of multipoles and near-field distributions confirm that the toroidal dipole and magnetic quadrupole dominate the dual qBICs resonance. The high performance of slow light with ultralarge group index exceeding 5.6 × 105 and the inverse quadratic law between the group index and asymmetric parameter are achieved. By temperature tuning of the VO2 thin film at the sub-10 K scale, a modulation depth of 90% and the ON/OFF ratio exceeding 12.8 dB are obtained. The proposed temperature tunable dual qBICs have potential applications in the fields of tunable slow light, temperature switches, and sensors.

7.
J Org Chem ; 89(8): 5560-5572, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38564232

RESUMO

A simple, efficient, and practical method for the synthesis of S-quinolyl xanthates was developed via Ts2O-promoted deoxygenative C-H dithiocarbonation of quinoline N-oxides with various potassium O-alkyl xanthates. The reaction performed well under transition-metal-free, base-free, and room-temperature conditions with wide substrate tolerance. Employing potassium O-tert-butyl xanthate (tBuOCS2K) as a nucleophile, some valuable quinoline-2-thiones were unexpectedly obtained in a one-pot reaction without any additional base.

8.
Org Biomol Chem ; 22(12): 2409-2413, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38411219

RESUMO

A convenient, efficient and practical approach for the synthesis of S-quinolyl phosphorothioates via cheap TsCl promoted deoxygenative C2-H phosphorothiolation of quinoline N-oxides with readily available triethylammonium O,O-dialkylphosphorothioates was developed. The reaction performed well under transition-metal-free conditions at room temperature with a very short reaction time (10-20 min). Preliminary studies showed that the current transformation underwent a nucleophilic substitution process.

9.
Org Biomol Chem ; 22(18): 3740-3745, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38651658

RESUMO

An efficient and practical method for the synthesis of 3-alkenylquinoxalinones containing the SCF3 group has been readily developed through a three-component radical cascade reaction involving quinoxalinones, alkynes and AgSCF3. The reaction was found to be compatible with a variety of substrates and exhibited a high functional group tolerance and complete E-selectivity. The preliminary study suggests the involvement of a SCF3 radical in the transformation.

10.
BMC Infect Dis ; 24(1): 920, 2024 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-39232674

RESUMO

BACKGROUND: Sepsis remains a leading cause of mortality in intensive care units, and rapid and accurate pathogen detection is crucial for effective treatment. This study evaluated the clinical application of multi-site metagenomic next-generation sequencing (mNGS) for the diagnosis of sepsis, comparing its performance against conventional methods. METHODS: A retrospective analysis was conducted on 69 patients with sepsis consecutively admitted to the Department of Intensive Care Medicine, Meizhou People's Hospital. Samples of peripheral blood and infection sites were collected for mNGS and conventional method tests to compare the positive rate of mNGS and traditional pathogen detection methods and the distribution of pathogens. The methods used in this study included a comprehensive analysis of pathogen consistency between peripheral blood and infection site samples. Additionally, the correlation between the pathogens detected and clinical outcomes was investigated. RESULTS: Of the patients with sepsis, 57.97% experienced dyspnea, and 65.2% had underlying diseases, with hypertension being the most common. mNGS demonstrated a significantly higher pathogen detection rate (88%) compared to the conventional method tests (26%). The pathogen consistency rate was 60% between plasma and bronchoalveolar lavage fluid samples, and that of plasma and local body fluid samples was 63%. The most frequently detected pathogens were gram-negative bacteria, and Klebsiella pneumonia. There were no significant differences in the clinical features between the pathogens. CONCLUSION: mNGS is significantly superior to conventional methods in pathogen detection. There was a notable high pathogen consistency detection between blood and local body fluid samples, supporting the clinical relevance of mNGS. This study highlights the superiority of mNGS in detecting a broad spectrum of pathogens quickly and accurately. TRIAL REGISTRATION: Not applicable.


Assuntos
Sequenciamento de Nucleotídeos em Larga Escala , Unidades de Terapia Intensiva , Metagenômica , Sepse , Humanos , Sepse/diagnóstico , Sepse/microbiologia , Masculino , Feminino , Pessoa de Meia-Idade , Estudos Retrospectivos , Idoso , Metagenômica/métodos , Adulto , Bactérias/isolamento & purificação , Bactérias/genética , Bactérias/classificação , Idoso de 80 Anos ou mais
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