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2.
BMC Cancer ; 23(1): 1225, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38087256

RESUMO

BACKGROUNDS: The purpose of this study is to investigate the relationship between clinical characteristics and cervical lymph node metastasis (LNM) in patients with thyroid carcinoma, as well as estimate the preoperative diagnosis values of ultrasound (US) and contrast enhanced computed tomography (CECT) examinations on the neck for detection of cervical LNM in thyroid carcinoma. METHODS: A retrospective analysis of 3 026 patients with surgically proven thyroid carcinoma was conducted. Patients' clinical characteristics, including gender, age, tumor size, bilateral lesions, multifocality, adenomatous nodules, Hashimoto's thyroiditis (HT), and extrathyroidal extension, were collected to explore their association with cervical LNM in thyroid carcinoma. Preoperative assessments for central lymph node metastasis (CLNM) and lateral lymph node metastasis (LLNM) were conducted through US and CECT. The diagnostic value of US, CECT and US combined with CECT for detection of LNM located in various cervical compartments was estimated based on the pathological results. RESULTS: The risk of cervical LNM was higher in thyroid cancer patients who were male, age < 55 years old, tumor size > 10 mm, bilateral lesions, and extrathyroidal extension, while multifocality, adenomatous nodules and HT had no significant effect on LNM. US, CECT and US combined with CECT all had a higher sensitivity to LLNM (93.1%, 57.8%, 95.4%) than to CLNM (32.3%, 29.0%, 43.4%). US and CECT had a high specificity to both CLNM and LLNM (94.3-97.8%). CONCLUSION: Preoperative clinical characteristics and imaging examinations on patients with thyroid carcinoma are crucial to the evaluation of cervical lymph nodes and conducive to individualizing surgical treatments by clinicians. US combined with CECT are superior to single US or CECT alone in detection of CLNM and LLNM.


Assuntos
Carcinoma Papilar , Neoplasias da Glândula Tireoide , Humanos , Masculino , Pessoa de Meia-Idade , Feminino , Câncer Papilífero da Tireoide/patologia , Estudos Retrospectivos , Metástase Linfática/diagnóstico por imagem , Metástase Linfática/patologia , Fatores de Risco , Carcinoma Papilar/patologia , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Neoplasias da Glândula Tireoide/cirurgia , Neoplasias da Glândula Tireoide/complicações , Linfonodos/patologia
3.
Nature ; 619(7970): 572-584, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37468586

RESUMO

The intestine is a complex organ that promotes digestion, extracts nutrients, participates in immune surveillance, maintains critical symbiotic relationships with microbiota and affects overall health1. The intesting has a length of over nine metres, along which there are differences in structure and function2. The localization of individual cell types, cell type development trajectories and detailed cell transcriptional programs probably drive these differences in function. Here, to better understand these differences, we evaluated the organization of single cells using multiplexed imaging and single-nucleus RNA and open chromatin assays across eight different intestinal sites from nine donors. Through systematic analyses, we find cell compositions that differ substantially across regions of the intestine and demonstrate the complexity of epithelial subtypes, and find that the same cell types are organized into distinct neighbourhoods and communities, highlighting distinct immunological niches that are present in the intestine. We also map gene regulatory differences in these cells that are suggestive of a regulatory differentiation cascade, and associate intestinal disease heritability with specific cell types. These results describe the complexity of the cell composition, regulation and organization for this organ, and serve as an important reference map for understanding human biology and disease.


Assuntos
Intestinos , Análise de Célula Única , Humanos , Diferenciação Celular/genética , Cromatina/genética , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Regulação da Expressão Gênica , Mucosa Intestinal/citologia , Intestinos/citologia , Intestinos/imunologia , Análise da Expressão Gênica de Célula Única
4.
Cell ; 175(3): 679-694.e22, 2018 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-30340040

RESUMO

Dietary soluble fibers are fermented by gut bacteria into short-chain fatty acids (SCFA), which are considered broadly health-promoting. Accordingly, consumption of such fibers ameliorates metabolic syndrome. However, incorporating soluble fiber inulin, but not insoluble fiber, into a compositionally defined diet, induced icteric hepatocellular carcinoma (HCC). Such HCC was microbiota-dependent and observed in multiple strains of dysbiotic mice but not in germ-free nor antibiotics-treated mice. Furthermore, consumption of an inulin-enriched high-fat diet induced both dysbiosis and HCC in wild-type (WT) mice. Inulin-induced HCC progressed via early onset of cholestasis, hepatocyte death, followed by neutrophilic inflammation in liver. Pharmacologic inhibition of fermentation or depletion of fermenting bacteria markedly reduced intestinal SCFA and prevented HCC. Intervening with cholestyramine to prevent reabsorption of bile acids also conferred protection against such HCC. Thus, its benefits notwithstanding, enrichment of foods with fermentable fiber should be approached with great caution as it may increase risk of HCC.


Assuntos
Carcinoma Hepatocelular/etiologia , Colestase/complicações , Fibras na Dieta/metabolismo , Disbiose/complicações , Fermentação , Microbioma Gastrointestinal , Neoplasias Hepáticas/etiologia , Animais , Carcinoma Hepatocelular/microbiologia , Linhagem Celular Tumoral , Colestase/microbiologia , Dieta Hiperlipídica/efeitos adversos , Disbiose/microbiologia , Inulina/efeitos adversos , Neoplasias Hepáticas/microbiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL
5.
Drug Dev Ind Pharm ; 43(4): 558-573, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27935330

RESUMO

OBJECTIVE: This work aimed to develop an alternative sustained-release thermosensitive praziquantel-loaded nanoemulsion (PZQ-NE) hydrogel for better schistosomiasis treatment. SIGNIFICANCE: PZQ-NE-dispersed chitosan/glycerol 2-phosphate disodium/HPMC (NE/CS/ß-GP/HMPC) hydrogel was successfully prepared to improve bioavailability of PZQ. METHODS: Solubility tests and pseudo-ternary phase diagrams were applied to screen optimal oils, surfactants and co-surfactants of NE. The hydrogels were characterized for gelling time, surface exudates, rheological properties and in vitro drug release. Formulation optimization of NE/CS/ß-GP/HMPC hydrogel was conducted by Box-Behnken experimental design combined with response surface methodology. In vitro cytotoxicity of hydrogel was studied by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide method. The sustained-release property of PZQ in NE and optimized hydrogel was evaluated by pharmacokinetic study in rabbits. RESULTS: The formulation of PZQ-NE consisted of mass ratio of 12.5% capryol 90 containing PZQ (160 mg/g), 40% cremophor RH 40/tween 20 and transcutol HP (S/CoS = 2:1), 47.5% deionized water. PZQ releasing from NE/CS/ß-GP/HMPC hydrogels was best fitted to Higuchi model and governed by diffusion. Rheological investigation evidenced the themosensitive gelation of different hydrogel systems and their gel-like character at 37 °C. The optimized hydrogel formulation consisted of HPMC solution (103.69 mg/g), 3.03% (w/v) chitosan and 14.1% (w/v) ß-GP showed no cytotoxicity when the addition of NE was no more than 100 mg/g. Pharmacokinetic parameters indicated that NE/CS/ß-GP/HMPC hydrogel can significantly slow down drug elimination, prolong mean residence time and improve bioavailability of PZQ. CONCLUSIONS: NE/CS/ß-GP/HMPC hydrogel possessed sustained-release property and could be an alternative antischistosomal drug delivery system with improved therapeutic effect.


Assuntos
Preparações de Ação Retardada/química , Emulsões/química , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Nanopartículas/química , Praziquantel/química , Animais , Disponibilidade Biológica , Química Farmacêutica/métodos , Quitosana/química , Preparações de Ação Retardada/metabolismo , Feminino , Glicerofosfatos/química , Hidrogel de Polietilenoglicol-Dimetacrilato/metabolismo , Masculino , Praziquantel/metabolismo , Coelhos , Reologia , Solubilidade , Soluções/química , Tensoativos/química , Temperatura
6.
Stem Cell Reports ; 5(3): 392-404, 2015 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-26321145

RESUMO

Multipotent human mesenchymal stromal cells (hMSCs) harbor immunomodulatory properties that are therapeutically relevant. One of the most clinically important populations of leukocytes is the interleukin-17A (IL-17A)-secreting T (Th17) lymphocytes. However, mechanisms of hMSC and Th17 cell interactions are incompletely resolved. We found that, along with Th1 responses, hMSCs strongly suppressed Th17 responses and this required both IL-25--also known as IL--17E-as well as programmed death ligand-1 (PD-L1), a potent cell surface ligand for tolerance induction. Knockdown of IL-25 expression in hMSCs abrogated Th17 suppression in vitro and in vivo. However, IL-25 alone was insufficient to significantly suppress Th17 responses, which also required surface PD-L1 expression. Critically, IL-25 upregulated PD-L1 surface expression through the signaling pathways of JNK and STAT3, with STAT3 found to constitutively occupy the proximal region of the PD-L1 promoter. Our findings demonstrate the complexities of hMSC-mediated Th17 suppression, and highlight the IL-25/STAT3/PD-L1 axis as a candidate therapeutic target.


Assuntos
Antígeno B7-H1/imunologia , Interleucina-17/imunologia , Células-Tronco Mesenquimais/imunologia , Fator de Transcrição STAT3/imunologia , Células Th17/imunologia , Transcrição Gênica/imunologia , Antígeno B7-H1/genética , Regulação da Expressão Gênica/imunologia , Técnicas de Silenciamento de Genes , Humanos , Células-Tronco Mesenquimais/citologia , Fator de Transcrição STAT3/genética , Células Th17/citologia
8.
Int J Hematol ; 102(4): 394-400, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26243624

RESUMO

B cell-activating factor of the tumor necrosis factor family (BAFF) and a proliferation-inducing ligand (APRIL) play crucial roles in B cell development, survival, and antibody production. Autoimmune hemolytic anemia (AIHA) is an acquired autoimmune disease that occurs when antibodies target autologous red blood cells. Here, we analyzed the serum levels of BAFF and APRIL and their respective clinical associations in patients with AIHA. Serum BAFF and APRIL levels in patients with AIHA were significantly higher (P < 0.01) than in healthy individuals. Serum BAFF and APRIL levels were significantly augmented in patients with lower hemoglobin levels (hemoglobin was <8 g/dL) and higher LDH activity (LDH > 480 IU/mL). Glucocorticoid treatment dramatically reduced serum levels of BAFF and APRIL. Thus, serum BAFF and APRIL levels may reflect the clinical activity of this disease. Our results indicate that analysis of serum concentrations of BAFF and APRIL potentially represents a useful tool for the assessment of AIHA disease activity and progression.


Assuntos
Anemia Hemolítica Autoimune/sangue , Fator Ativador de Células B/sangue , Membro 13 da Superfamília de Ligantes de Fatores de Necrose Tumoral/sangue , Adulto , Idoso , Anemia Hemolítica Autoimune/tratamento farmacológico , Feminino , Glucocorticoides/administração & dosagem , Humanos , Masculino , Pessoa de Meia-Idade
9.
Nat Cell Biol ; 17(7): 856-67, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26098572

RESUMO

Oncogenic transcription factors are known to mediate the conversion of somatic cells to tumour or induced pluripotent stem cells (iPSCs). Here we report c-Jun as a barrier for iPSC formation. c-Jun is expressed by and required for the proliferation of mouse embryonic fibroblasts (MEFs), but not mouse embryonic stem cells (mESCs). Consistently, c-Jun is induced during mESC differentiation, drives mESCs towards the endoderm lineage and completely blocks the generation of iPSCs from MEFs. Mechanistically, c-Jun activates mesenchymal-related genes, broadly suppresses the pluripotent ones, and derails the obligatory mesenchymal to epithelial transition during reprogramming. Furthermore, inhibition of c-Jun by shRNA, dominant-negative c-Jun or Jdp2 enhances reprogramming and replaces Oct4 among the Yamanaka factors. Finally, Jdp2 anchors 5 non-Yamanaka factors (Id1, Jhdm1b, Lrh1, Sall4 and Glis1) to reprogram MEFs into iPSCs. Our studies reveal c-Jun as a guardian of somatic cell fate and its suppression opens the gate to pluripotency.


Assuntos
Reprogramação Celular/genética , Células-Tronco Embrionárias/metabolismo , Fibroblastos/metabolismo , Células-Tronco Pluripotentes Induzidas/metabolismo , Proteínas Proto-Oncogênicas c-jun/genética , Animais , Proliferação de Células/genética , Células Cultivadas , Embrião de Mamíferos/citologia , Transição Epitelial-Mesenquimal/genética , Feminino , Perfilação da Expressão Gênica , Células HEK293 , Humanos , Immunoblotting , Masculino , Camundongos da Linhagem 129 , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA , Camundongos Endogâmicos ICR , Camundongos Transgênicos , Microscopia Confocal , Fator 3 de Transcrição de Octâmero/genética , Proteínas Proto-Oncogênicas c-jun/metabolismo , Interferência de RNA , Proteínas Repressoras
10.
Int J Syst Evol Microbiol ; 63(Pt 8): 3009-3013, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23396724

RESUMO

A novel halophilic, filamentous actinobacterium, designated strain TRM 40139(T), was isolated from a hypersaline habitat in Xinjiang Province, north-west China. Its taxonomic status was determined using a polyphasic approach. Phylogenetic analysis based on the almost-complete 16S rRNA gene sequence of the strain showed that it formed a well-separated sub-branch within the radiation of the genus Actinopolyspora and the organism was related most closely to the type strains of Actinopolyspora alba (97.6 % similarity), Actinopolyspora xinjiangensis (97.6 %) and Actinopolyspora erythraea (97.1 %). However, it had relatively lower mean DNA-DNA relatedness values with the above strains (36.4, 31.3 and 26.1 %, respectively). Optimal growth occurred at 35 °C, at pH 7.0 and in the presence of 12 % (w/v) NaCl. The whole-cell sugar pattern consisted of xylose, glucose, ribose and arabinose. The major fatty acids were iso-C16 : 0 (28.0 %) and anteiso-C17 : 0 (27.6 %). The diagnostic phospholipids detected were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylcholine, phosphatidylinositol and two unknown phospholipids. The predominant menaquinones were MK-9(H4) (49.8 %) and MK-10(H4) (24.2 %). The G+C content of the genomic DNA was 66.4 mol%. Strain TRM 40139(T) therefore represents a novel species of the genus Actinopolyspora, for which the name Actinopolyspora lacussalsi sp. nov. is proposed. The type strain is TRM 40139(T) (= KCTC 19657(T) = CCTCC AA 2012020(T)).


Assuntos
Actinomycetales/classificação , Lagos/microbiologia , Filogenia , Microbiologia da Água , Actinomycetales/genética , Actinomycetales/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/análise , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , Fosfolipídeos/análise , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Cloreto de Sódio , Vitamina K 2/análise
11.
Lab Invest ; 90(3): 374-82, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20084057

RESUMO

In this study, we examine the effects of tissue inhibitor of metalloproteinases-2 (TIMP-2) on the phosphorylation status of specific phosphotyrosine residues on the vascular endothelial cell growth factor receptor-2 (VEGFR-2) cytoplasmic tail and examine the effects on associated downstream signaling pathways. To focus on metalloproteinase-independent mechanisms, we used the TIMP-2 analog known as Ala+TIMP-2 that is deficient in matrix metalloproteinase-inhibitory activity. Our experiments are designed to compare the effects of VEGF-A stimulation with or without Ala+TIMP-2 pretreatment, as well as basal responses in human microvascular endothelial cells. Our results show that Ala+TIMP-2 selectively alters the phosphorylation pattern of VEGFR-2 after VEGF-A stimulation and disrupts the downstream activation of PLC-gamma, Ca(+2) flux, Akt, and eNOS, as well as decreasing cGMP levels. Moreover, we observed an Ala+TIMP-2-induced reduction in cGMP levels typically elevated by exogenous NO donors implicating Ala+TIMP-2 in the direct activation of an isobutylmethylxanthine (IBMX)-sensitive cGMP phosphodiesterase activity. TIMP-2 suppression of endothelial mitogenesis and angiogenesis involves at least two mechanisms, one mediated by protein tyrosine phosphatase inhibition of VEGFR-2 activation as well as downstream signaling and a second mechanism involving direct activation of an IBMX-sensitive phosphodiesterase activity.


Assuntos
Células Endoteliais/metabolismo , Diester Fosfórico Hidrolases/metabolismo , Inibidor Tecidual de Metaloproteinase-2/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo , 1-Metil-3-Isobutilxantina , Cálcio/metabolismo , Linhagem Celular , Movimento Celular , Proliferação de Células , GMP Cíclico/metabolismo , Ativação Enzimática , Matriz Extracelular/metabolismo , Humanos , Óxido Nítrico/metabolismo , Doadores de Óxido Nítrico , Óxido Nítrico Sintase Tipo III/metabolismo , Fosfolipase C gama/metabolismo , Fosforilação , Proteínas Proto-Oncogênicas c-akt/metabolismo
12.
Microvasc Res ; 76(3): 145-51, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18721821

RESUMO

We have previously reported that tissue inhibitor of metalloproteinases-2 (TIMP-2), an endogenous inhibitor of matrix metalloproteinase, modulates angiogenic responses through the MMP inhibition-independent activity. In this study, we investigate the molecular mechanisms of TIMP-2-mediated growth inhibition in response to fibroblast growth factor-2 (FGF-2). Pre-treatment with a protein tyrosine phosphatase inhibitor orthovanadate or expression of a dominant negative Shp-1 mutant fails to induce TIMP-2 inactivation of FGF-2 signaling pathways in human microvascular endothelial cells. We also show that TIMP-2 inhibition of FGF-2-induced p42/44(MAPK) activation and cell proliferation is associated with TIMP-2 binding to integrin alpha3beta1 on endothelial cell surfaces, as demonstrated by use of anti-integrin alpha3 or beta1 blocking antibodies, or disruption of integrin alpha3 expression by siRNA. Collectively, our results indicate that TIMP-2 inhibits FGF-2 signaling pathways through association with integrin alpha3beta1 and Shp-1-dependent inhibition of p42/44(MAPK) signaling, which in turn, results in suppression of FGF-2-stimulated endothelial cell mitogenesis.


Assuntos
Células Endoteliais/efeitos dos fármacos , Fator 2 de Crescimento de Fibroblastos/farmacologia , Transdução de Sinais/efeitos dos fármacos , Inibidor Tecidual de Metaloproteinase-2/farmacologia , Sequência de Bases , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Células Endoteliais/citologia , Células Endoteliais/fisiologia , Fator 2 de Crescimento de Fibroblastos/fisiologia , Humanos , Integrina alfa3beta1/antagonistas & inibidores , Integrina alfa3beta1/genética , Integrina alfa3beta1/fisiologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/fisiologia , Metaloproteinases da Matriz/fisiologia , Proteína Quinase 1 Ativada por Mitógeno/antagonistas & inibidores , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/antagonistas & inibidores , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Neovascularização Fisiológica , Proteína Tirosina Fosfatase não Receptora Tipo 6/fisiologia , RNA Interferente Pequeno/genética , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/fisiologia , Proteínas Recombinantes/farmacologia , Transdução de Sinais/fisiologia , Inibidor Tecidual de Metaloproteinase-2/fisiologia
13.
Cell ; 114(2): 171-80, 2003 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-12887919

RESUMO

Tissue inhibitors of metalloproteinases (TIMPs) suppress matrix metalloproteinase (MMP) activity critical for extracellular matrix turnover associated with both physiologic and pathologic tissue remodeling. We demonstrate here that TIMP-2 abrogates angiogenic factor-induced endothelial cell proliferation in vitro and angiogenesis in vivo independent of MMP inhibition. These effects require alpha 3 beta 1 integrin-mediated binding of TIMP-2 to endothelial cells. Further, TIMP-2 induces a decrease in total protein tyrosine phosphatase (PTP) activity associated with beta1 integrin subunits as well as dissociation of the phosphatase SHP-1 from beta1. TIMP-2 treatment also results in a concomitant increase in PTP activity associated with tyrosine kinase receptors FGFR-1 and KDR. Our findings establish an unexpected, MMP-independent mechanism for TIMP-2 inhibition of endothelial cell proliferation in vitro and reveal an important component of the antiangiogenic effect of TIMP2 in vivo.


Assuntos
Inibidores da Angiogênese/farmacologia , Endotélio Vascular/efeitos dos fármacos , Metaloproteinases da Matriz/metabolismo , Neovascularização Fisiológica/fisiologia , Inibidor Tecidual de Metaloproteinase-2/farmacologia , Inibidores da Angiogênese/genética , Animais , Ligação Competitiva , Divisão Celular/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Embrião de Mamíferos/citologia , Fatores de Crescimento Endotelial/metabolismo , Endotélio Vascular/citologia , Endotélio Vascular/metabolismo , Inibidores Enzimáticos/farmacologia , Fator 2 de Crescimento de Fibroblastos/metabolismo , Fibroblastos/metabolismo , Humanos , Integrina alfa3beta1/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular , Camundongos , Neovascularização Fisiológica/efeitos dos fármacos , Proteína Tirosina Fosfatase não Receptora Tipo 1 , Proteína Tirosina Fosfatase não Receptora Tipo 6 , Proteínas Tirosina Fosfatases/efeitos dos fármacos , Proteínas Tirosina Fosfatases/metabolismo , Receptores Proteína Tirosina Quinases/farmacologia , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos , Receptores de Fatores de Crescimento de Fibroblastos , Proteínas Recombinantes/farmacologia , Inibidor Tecidual de Metaloproteinase-2/genética , Vanadatos/farmacologia , Fator A de Crescimento do Endotélio Vascular , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo
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