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1.
Stem Cells ; 42(5): 460-474, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38381592

RESUMO

Cell therapy based on mesenchymal stem cells (MSCs) alleviate muscle atrophy caused by diabetes and aging; however, the impact of human umbilical cord mesenchymal stem cells on muscle atrophy following nerve injury and the underlying mechanisms remain unclear. In this study, we evaluated the therapeutic efficacy of human umbilical cord MSCs (hucMSCs) and hucMSC-derived exosomes (hucMSC-EXOs) for muscle atrophy following nerve injury and identified the underlying molecular mechanisms. Sciatic nerve crush injury in rats and the induction of myotubes in L6 cells were used to determine the ameliorating effect of hucMSCs and hucMSC-EXOs on muscle atrophy. Q-PCR and Western blot analyses were used to measure the expression of muscle-specific ubiquitin ligases Fbxo32 (Atrogin1, MAFbx) and Trim63 (MuRF-1). Dual-luciferase reporter gene experiments were conducted to validate the direct binding of miRNAs to their target genes. Local injection of hucMSCs and hucMSC-EXOs mitigated atrophy in the rat gastrocnemius muscle following sciatic nerve crush injury. In vitro, hucMSC-EXOs alleviated atrophy in L6 myotubes. Mechanistic analysis indicated the upregulation of miR-23b-3p levels in L6 myotubes following hucMSC-EXOs treatment. MiR-23b-3p significantly inhibited the expression of its target genes, Fbxo32 and Trim63, and suppressed myotube atrophy. Notably, an miR-23b-3p inhibitor reversed the inhibitory effect of miR-23b-3p on myotube atrophy in vitro. These results suggest that hucMSCs and their exosomes alleviate muscle atrophy following nerve injury. MiR-23b-3p in exosomes secreted by hucMSCs contributes to this mechanism by inhibiting the muscle-specific ubiquitination ligases Fbxo32 and Trim63.


Assuntos
Exossomos , Células-Tronco Mesenquimais , Atrofia Muscular , Traumatismos dos Nervos Periféricos , Ubiquitina-Proteína Ligases , Exossomos/metabolismo , Animais , Atrofia Muscular/patologia , Atrofia Muscular/metabolismo , Atrofia Muscular/terapia , Atrofia Muscular/genética , Humanos , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitina-Proteína Ligases/genética , Células-Tronco Mesenquimais/metabolismo , Ratos , Traumatismos dos Nervos Periféricos/metabolismo , Traumatismos dos Nervos Periféricos/patologia , Traumatismos dos Nervos Periféricos/terapia , Ratos Sprague-Dawley , Proteínas Ligases SKP Culina F-Box/metabolismo , Proteínas Ligases SKP Culina F-Box/genética , Cordão Umbilical/citologia , Músculo Esquelético/patologia , Músculo Esquelético/metabolismo , Masculino , Proteínas com Motivo Tripartido/metabolismo , Proteínas com Motivo Tripartido/genética , MicroRNAs/genética , MicroRNAs/metabolismo , Proteínas Musculares/metabolismo , Proteínas Musculares/genética , Fibras Musculares Esqueléticas/metabolismo , Fibras Musculares Esqueléticas/patologia
2.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 46(3): 307-315, 2024 Jun.
Artigo em Zh | MEDLINE | ID: mdl-38548389

RESUMO

Objective To investigate the effects of platelet-rich plasma-derived exosomes (PRP-Exos) on the proliferation and migration of tendon stem/progenitor cell (TSPC).Methods PRP-Exos were extracted through the combination of polymer-based precipitation and ultracentrifugation.The morphology,concentration,and particle size of PRP-Exos were identified by transmission electron microscopy and nanoparticle tracking analysis.The expression levels of surface marker proteins on PRP-Exos and platelet membrane glycoproteins were determined by Western blot analysis.Rat TSPC was extracted and cultured,and the expression of surface marker molecules on TSPC was detected using flow cytometry and immunofluorescence staining.The proliferation of TSPC influenced by PRP-Exos was evaluated using CCK-8 assay and EdU assay.The effect of PRP-Exos on the migration of TSPC was evaluated by cell scratch assay and Transwell assay.Results The extracted PRP-Exos exhibit typical saucer-like structures,with a concentration of 4.9×1011 particles/mL,an average particle size of (132.2±56.8) nm,and surface expression of CD9,CD63 and CD41.The extracted TSPC expressed the CD44 protein.PRP-Exos can be taken up by TSPC,and after co-cultured for 48 h,concentrations of 50 and 100 µg/mL of PRP-Exos significantly promoted the proliferation of TSPC (both P<0.001),with no statistical difference between the two concentrations (P=0.283).Additionally,after co-cultured for 24 h,50 µg/mL of PRP-Exos significantly promoted the migration of TSPC (P<0.001).Conclusion Under in vitro culture conditions,PRP-Exos significantly promote the proliferation and migration of rat TSPC.


Assuntos
Movimento Celular , Proliferação de Células , Exossomos , Plasma Rico em Plaquetas , Células-Tronco , Tendões , Exossomos/metabolismo , Plasma Rico em Plaquetas/metabolismo , Ratos , Células-Tronco/citologia , Células-Tronco/metabolismo , Animais , Tendões/citologia , Tendões/metabolismo , Células Cultivadas , Ratos Sprague-Dawley , Masculino
3.
Oncologist ; 28(4): e191-e197, 2023 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-36779523

RESUMO

BACKGROUND: Anlotinib is a multi-target tyrosine kinase inhibitor that can effectively inhibit tumor cell proliferation after receptor kinase activation caused by KIT gene mutation. METHODS: We tested the inhibitory effect of anlotinib in GIST cell lines with different gene mutations and evaluated the efficacy of anlotinib for patients with metastatic GIST after imatinib failure in a multicenter, single-arm, phase II study. RESULTS: In vitro, V654A mutation encoded by KIT exon 13 was intermediately sensitive to anlotinib. Moreover, anlotinib was able to partly suppress the activation loop mutation D820A from exon 17 while another activation loop mutation N822K, also from exon 17, was resistant to anlotinib. From September 2018 to October 2020, 64 patients from 9 Chinese medical centers were enrolled in this study. Seven patients had partial response and 39 patients had stable disease. The median PFS was 8.0 months. There was no statistical significance comparing with PFS of sunitinib second-line therapy at the same period. The most common adverse events related to anlotinib treatment were hypertension, neutropenia, and fatigue. CONCLUSION: Anlotinib showed moderate antitumor activity in drug-resistant GIST cell lines in vitro, and good PFS and better tolerance in second-line therapy study.


Assuntos
Antineoplásicos , Tumores do Estroma Gastrointestinal , Humanos , Tumores do Estroma Gastrointestinal/tratamento farmacológico , Tumores do Estroma Gastrointestinal/genética , Tumores do Estroma Gastrointestinal/patologia , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Estudos Prospectivos , Sunitinibe/uso terapêutico , Mutação , Proteínas Proto-Oncogênicas c-kit/genética , Resistencia a Medicamentos Antineoplásicos/genética
4.
Eur Radiol ; 33(4): 2331-2339, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36418625

RESUMO

OBJECTIVE: To study the clinical value of three-dimensional ultrasonography (3D-US) in the morphological evaluation of rotator cuff tears (RCTs). METHODS: Based on previously published literature, RCT patterns in our study were divided into crescent, L-shaped with the remnant tendon retracted to the anterior rotator cuff (aL-shaped), L-shaped with the remnant tendon retracted to the posterior rotator cuff (pL-shaped), T-shaped (a tear pattern that is a combination of aL-shaped and pL-shaped), U-shaped, and massive type. Two radiologists prospectively assessed the tear patterns using 3D-US as well as magnetic resonance imaging (MRI) and compared these results using arthroscopy to calculate diagnostic accuracy. RESULT: Fifty-two patients (52 shoulders) were enrolled. The overall diagnostic accuracy of 3D-US in evaluating RCT patterns (82.7%, 43/52; 95% CI: 72.1-93.3%) was significantly higher (p = 0.008) than that of the MRI (57.7%, 31/52; 95% CI: 45.8-73.4%). The accuracy of 3D-US was higher than that of MRI for most types of tears (crescent: 95.0% vs. 55.0%, aL-shaped: 83.3% vs. 77.8%, pL-shaped: 50.0% vs. 25.0%, T-shaped: 75.0% vs. 0.0%, and massive type: 80.0% vs. 100.0%). The accuracies of 3D-US with respect to evaluation by the two radiologists were 84.6% (44/52) and 76.9% (40/52), and there was substantial agreement evident (κ = 0.709). The time taken by the two radiologists to reconstruct the 3D-US images and evaluate the tear pattern was < 5 min. CONCLUSION: The 3D-US can be used for the preoperative evaluation of RCT patterns, and thus be useful for the correct selection of the surgical repair technique for RCTs. KEY POINTS: • Few studies have been found exploring the value of 3D-US for the morphological evaluation of RCTs and correlated with the arthroscopic findings. • Based on previous studies on the morphological classification, anterior L shape (aL-shaped), and posterior L shape (pL-shaped) were used for the first time to describe the torn patterns of RCT.


Assuntos
Lesões do Manguito Rotador , Humanos , Lesões do Manguito Rotador/diagnóstico por imagem , Estudos Prospectivos , Manguito Rotador/diagnóstico por imagem , Manguito Rotador/cirurgia , Tendões/cirurgia , Ruptura , Ultrassonografia , Artroscopia/métodos , Imageamento por Ressonância Magnética
5.
Eur Radiol ; 2023 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-37855852

RESUMO

OBJECTIVES: In this study, ultrasound (US) contrast arthrography and subacromial-subdeltoid bursography with the contrast agent of SonoVue were performed to evaluate their value for detecting and differentiating the rotator cuff tear (RCT) subtypes in patients with the uncertain RCT. METHODS: A total of 102 patients with the clinically suspected RCTs in the orthopedic clinic were prospectively recruited and underwent conventional high-frequency US for the category of undoubted full-thickness RCT, uncertain RCT, and intact rotator cuff. Among these patients, the patients with uncertain RCT underwent the subsequent US contrast arthrography and subacromial-subdeltoid bursography. The arthroscopic findings were used as the gold standard in this study. RESULTS: After the conventional US screening, 62 patients with uncertain RCT underwent the subsequent US contrast arthrography and subacromial-subdeltoid bursography. All the US contrast arthrography and subacromial-subdeltoid bursography were successfully performed and no severe side effects were observed in all the patients. For full-thickness tears, the sensitivity and specificity of the combined US contrast arthrography and subacromial-subdeltoid bursography were 94.7% (CI: 0.72-1.0) and 81.4% (CI: 0.66-0.91), respectively, and for articular-side tears 100% (CI: 0.51-1) and 100% (CI: 0.92-1), respectively, and for the bursal-side tears 84.6% (CI: 0.54-0.97) and 97.9% (CI: 0.88-1.0), respectively. The main inconsistency between the contrast-enhanced US and arthroscopy was that 7 patients with arthroscopic proved concurrent articular- and bursal-side tears were indicated as full-thickness RCTs on contrast-enhanced US. CONCLUSIONS: Combined US contrast arthrography and subacromial-subdeltoid bursography are useful for detecting the RCT subtypes in patients with the uncertain RCTs. CLINICAL RELEVANCE STATEMENT: When conventional high-frequency US has some difficulty in differentiating the full-thickness from partial-thickness RCTs, combined US contrast arthrography and subacromial-subdeltoid bursography could be used to improve the detection accuracy of RCT subtypes. KEY POINTS: • This is the first study by injection of the US contrast agent SonoVue into the shoulder joint cavity and subacromial-subdeltoid bursa for the detection and differentiation of the RCT subtypes among the people with the uncertain RCT by conventional US screening. • The SonoVue was injected into the glenohumeral joint cavity under US guidance to differentiate the full-thickness RCTs from partial-thickness RCTs. • Combined US contrast arthrography and subacromial-subdeltoid bursography are useful for detecting the RCT subtypes in patients with the uncertain RCTs.

6.
Nucleic Acids Res ; 49(7): 3796-3813, 2021 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-33744966

RESUMO

The family of Poly(A)-binding proteins (PABPs) regulates the stability and translation of messenger RNAs (mRNAs). Here we reported that the three members of PABPs, including PABPC1, PABPC3 and PABPC4, were identified as novel substrates for MKRN3, whose deletion or loss-of-function mutations were genetically associated with human central precocious puberty (CPP). MKRN3-mediated ubiquitination was found to attenuate the binding of PABPs to the poly(A) tails of mRNA, which led to shortened poly(A) tail-length of GNRH1 mRNA and compromised the formation of translation initiation complex (TIC). Recently, we have shown that MKRN3 epigenetically regulates the transcription of GNRH1 through conjugating poly-Ub chains onto methyl-DNA bind protein 3 (MBD3). Therefore, MKRN3-mediated ubiquitin signalling could control both transcriptional and post-transcriptional switches of mammalian puberty initiation. While identifying MKRN3 as a novel tissue-specific translational regulator, our work also provided new mechanistic insights into the etiology of MKRN3 dysfunction-associated human CPP.


Assuntos
Hormônio Liberador de Gonadotropina/genética , Proteínas de Ligação a Poli(A)/metabolismo , Precursores de Proteínas/genética , Puberdade Precoce , RNA Mensageiro/metabolismo , Ubiquitina-Proteína Ligases/fisiologia , Animais , Células HEK293 , Células HeLa , Humanos , Camundongos , Camundongos Knockout , Puberdade Precoce/genética , Puberdade Precoce/metabolismo , Ubiquitinação
7.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 45(3): 374-381, 2023 Jun.
Artigo em Zh | MEDLINE | ID: mdl-37106519

RESUMO

Objective To investigate the effect of human platelet-rich plasma-derived exosomes(PRP-exos)on the proliferation of Schwann cell(SC)cultured in vitro. Methods PRP-exos were extracted by polymerization-precipitation combined with ultracentrifugation.The morphology of PRP-exos was observed by transmission electron microscopy,and the concentration and particle size distribution of PRP-exos were determined by nanoparticle tracking analysis.Western blotting was employed to determine the expression of the marker proteins CD63,CD81,and CD9 on exosome surface and the platelet membrane glycoprotein CD41.The SCs of rats were isolated and cultured,and the expression of the SC marker S100ß was detected by immunofluorescence staining.The fluorescently labeled PRP-exos were co-cultured with SCs in vitro for observation of their interaction.EdU assay was employed to detect the effect of PRP-exos on SC proliferation,and CCK-8 assay to detect the effects of PRP-exos at different concentrations(0,10,20,40,80,and 160 µg/ml)on SC proliferation. Results The extracted PRP-exos appeared as uniform saucer-shaped vesicles with the average particle size of(122.8±38.7)nm and the concentration of 3.5×1012 particles/ml.CD63,CD81,CD9,and CD41 were highly expressed on PRP-exos surface(P<0.001,P=0.025,P=0.004,and P=0.032).The isolated SCs expressed S100ß,and PRP-exos could be taken up by SCs.PRP-exos of 40,80,and 160 µg/ml promoted the proliferation of SCs,and that of 40 µg/ml showed the best performance(all P<0.01). Conclusions High concentrations of PRP-exos can be extracted from PRP.PRP-exos can be taken up by SCs and promote the proliferation of SCs cultured in vitro.


Assuntos
Exossomos , Plasma Rico em Plaquetas , Humanos , Ratos , Animais , Exossomos/metabolismo , Células de Schwann , Técnicas de Cocultura , Proliferação de Células , Células Cultivadas
8.
Proc Natl Acad Sci U S A ; 116(45): 22746-22753, 2019 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-31636198

RESUMO

Gastrointestinal stromal tumors (GISTs) are the most common human sarcoma and are initiated by activating mutations in the KIT or PDGFRA receptor tyrosine kinases. Chromosome 22q deletions are well-recognized frequent abnormalities in GISTs, occurring in ∼50% of GISTs. These deletions are thought to contribute to the pathogenesis of this disease via currently unidentified tumor suppressor mechanisms. Using whole exome sequencing, we report recurrent genomic inactivated DEPDC5 gene mutations in GISTs (16.4%, 9 of 55 patients). The demonstration of clonal DEPDC5 inactivation mutations in longitudinal specimens and in multiple metastases from individual patients suggests that these mutations have tumorigenic roles in GIST progression. DEPDC5 inactivation promotes GIST tumor growth in vitro and in nude mice. DEPDC5 reduces cell proliferation through the mTORC1-signaling pathway and subsequently induces cell-cycle arrest. Furthermore, DEPDC5 modulates the sensitivity of GIST to KIT inhibitors, and the combination therapy with mTOR inhibitor and KIT inhibitor may work better in GIST patients with DEPDC5 inactivation. These findings of recurrent genomic alterations, together with functional data, validate the DEPDC5 as a bona fide tumor suppressor contributing to GIST progression and a biologically relevant target of the frequent chromosome 22q deletions.


Assuntos
Proteínas Ativadoras de GTPase/genética , Neoplasias Gastrointestinais/genética , Tumores do Estroma Gastrointestinal/genética , Alvo Mecanístico do Complexo 1 de Rapamicina/genética , Mutação , Animais , Deleção Cromossômica , Cromossomos Humanos Par 22 , Progressão da Doença , Neoplasias Gastrointestinais/patologia , Tumores do Estroma Gastrointestinal/patologia , Xenoenxertos , Humanos , Sequenciamento do Exoma
9.
Environ Res ; 197: 111053, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33785327

RESUMO

Heavy metals contained in sewage sludge may cause potential environmental pollution. In this study, compound binders were used to stabilize and solidify the sludge, which aims to reduce hazard of heavy metals. The strength and leaching behavior of heavy metals from treated sludge was investigated by performing a series of laboratory experiments including the unconfined compressive strength (UCS), the toxicity characteristic leaching procedure (TCLP), the sequential chemical extraction (SCE), and the semi-dynamic leaching test (Semi-DLT). The experimental results showed that the UCS of sludge was significantly improved after stabilization and solidification (S/S) treatment, therefore it can be used as low graded material for landfill. According to the TCLP tests, the selected heavy metals (i.e. Cr, Cu, Zn, Pb, Ni) became more stable under acid conditions in short term. From the SCE tests, some heavy metals were effectively converted into stable form in S/S process. The long term leaching behavior of the heavy metals was also evaluated by the diffusion coefficients (De) and leaching index (L) calculated by the data obtained from the Semi-DLT tests. Low De values showed the S/S treatment is effective for sewage sludge, while the calculated L values also meet the environmental requirement of heavy metal stability.


Assuntos
Metais Pesados , Esgotos , Poluição Ambiental , Metais Pesados/análise , Instalações de Eliminação de Resíduos
10.
J Ultrasound Med ; 40(7): 1401-1409, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33026685

RESUMO

OBJECTIVES: To evaluate the feasibility of a new simple ultrasound-guided transforaminal injection in patients with cervical radiculopathy. METHODS: Ultrasound scans of the neck in a plastic model and in 5 unaffected participants were first performed to identify the intervertebral foramen. Then ultrasound-guided transforaminal injections were performed in 20 patients with radiculopathy in the lower cervical spine, and computed tomography was used to verify the accuracy. Complications, the visual analog score, and the neck disability index were assessed at 1 and 3 months after the injection. RESULTS: Computed tomography confirmed that the needle tip was correctly placed in the intervertebral foramen in 88.5% (23 of 26) of injections. No immediate or short-term complications were observed in all patients. The visual analog score and neck disability index at 1 and 3 months were significantly lower than those before the injection (both P < .0001). CONCLUSIONS: Ultrasound may be a feasible and accurate method to guide cervical transforaminal injection.


Assuntos
Radiculopatia , Vértebras Cervicais/diagnóstico por imagem , Humanos , Injeções Epidurais , Radiculopatia/diagnóstico por imagem , Radiculopatia/tratamento farmacológico , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Ultrassonografia de Intervenção
11.
Carcinogenesis ; 41(1): 44-55, 2020 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-31046123

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) is a devastating disease with few therapeutic options, representing one of the great challenges in oncology. Activating KRAS mutation, occurring in >90% PDACs, is present in pancreatic intraepithelial neoplasia lesions, the precursor ductal lesions of PDAC, indicating additional genetic alterations contribute to the pathogenesis of PDAC. PDAC sequencing projects identify recurrent genomic ERBB2 alterations, mutations and amplifications, in 8.5% of PDAC patients, ranking as the top hit among the 100 receptor tyrosine kinases-encoding genes. Introduction of the ERBB2 mutations encoding protein variants S310F, S423R, R678Q, Q679L, E717D, L755S, V777L and V842I into human pancreatic epithelial cells causes oncogenic transformation, increasing ERBB2 signaling, anchorage-independent cell growth and tumor xenograft growth in nude mice, demonstrating that they are activating mutations. Interestingly, in many PDACs, mutations in ERBB2 and KRAS occur together. ERBB2 activating mutants facilitate KRAS-driven oncogenic properties. Introduction of ERBB2 mutations into KRAS-mutant PDAC cells activates ERBB2 signaling, promotes tumor growth and attenuates KRAS dependency. In contrast, a CRISPR-mediated knockout (KO) of ERBB2 in ERBB2-amplified PDAC cells inhibits ERBB2 signaling, colony formation, anchorage-independent growth and tumor xenograft formation. Finally, oncogenic ERBB2 aberrations can be abrogated by treatment with small-molecule inhibitors. ERBB2 and KRAS inhibition cooperate to suppress PDAC cell growth in vitro and to promote tumor regression in nude mice, providing a rationale for testing an anti-ERBB2 drug in combination with a KRAS inhibitor in ERBB2-mutant PDAC patients that are currently untreatable.


Assuntos
Carcinoma Ductal Pancreático/genética , Neoplasias Pancreáticas/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , Receptor ErbB-2/genética , Animais , Carcinoma Ductal Pancreático/tratamento farmacológico , Carcinoma Ductal Pancreático/mortalidade , Carcinoma Ductal Pancreático/patologia , Linhagem Celular Tumoral , Proliferação de Células/genética , Transformação Celular Neoplásica/genética , Variações do Número de Cópias de DNA , Conjuntos de Dados como Assunto , Progressão da Doença , Sinergismo Farmacológico , Técnicas de Inativação de Genes , Células HEK293 , Humanos , Masculino , Camundongos , Mutagênese Sítio-Dirigida , Mutação , Ductos Pancreáticos/patologia , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/mortalidade , Neoplasias Pancreáticas/patologia , Proteínas Proto-Oncogênicas p21(ras)/antagonistas & inibidores , Receptor ErbB-2/antagonistas & inibidores , Análise de Sobrevida , Ensaios Antitumorais Modelo de Xenoenxerto
12.
Gastric Cancer ; 23(5): 837-847, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32291709

RESUMO

BACKGROUND: The majority of GISTs express mutationally activated KIT. Imatinib and sunitinib are approved KIT-inhibiting therapies. Their efficacy is usually hampered by the acquired multiple secondary drug-resistance KIT mutations. The most problematic resistance subset is GISTs with acquisition of secondary mutations in the KIT activation loop. Here, we establish the spectrum of activity of dasatinib against a comprehensive collection of clinically relevant KIT mutants associated with drug-sensitive and drug-resistant GIST. METHODS: The cellular and in vitro activities of tyrosine kinase inhibitors (TKIs) against mutant KIT were assessed using a panel of engineered and GIST-derived cell lines. The in vivo activities of dasatinib were determined using TKI-resistant xenograft models. RESULTS: In engineered and GIST-derived cell lines, dasatinib potently inhibited KIT with primary mutations in exon 11 or 9 and a range of secondary imatinib-resistant mutations in exons 13 and 14, encoding the ATP-binding pocket, and in exons 17 and 18, encoding the activation loop, with the exception of a substitution at codon T670. Our data show that dasatinib is more potent than imatinib or sunitinib at inhibiting the activity of drug-resistant KIT mutants. Dasatinib also induces regression in GIST-derived xenograft models containing these secondary mutations. A major determinant of the efficacy of dasatinib for the treatment of advanced GIST is the activity of this inhibitor against KIT mutants. CONCLUSION: Dasatinib shows efficacy in cancer models, inhibiting a wide range of oncogenic primary and drug-resistant KIT mutants. These results have implications for the further development of dasatinib precision therapy in GIST patients.


Assuntos
Dasatinibe/farmacologia , Resistencia a Medicamentos Antineoplásicos/genética , Neoplasias Gastrointestinais/tratamento farmacológico , Tumores do Estroma Gastrointestinal/tratamento farmacológico , Mutação , Proteínas Proto-Oncogênicas c-kit/genética , Animais , Antineoplásicos/farmacologia , Apoptose , Movimento Celular , Proliferação de Células , Feminino , Neoplasias Gastrointestinais/genética , Neoplasias Gastrointestinais/patologia , Tumores do Estroma Gastrointestinal/genética , Tumores do Estroma Gastrointestinal/patologia , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
13.
J Ultrasound Med ; 39(8): 1507-1516, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32064662

RESUMO

OBJECTIVES: Super-resolution ultrasound (SRUS) has become a tool for in vivo microvascular imaging. Most of the SRUS methods are based on microbubble localization: namely, ultrasound localization microscopy (ULM). The aim of this study was to develop a nonlocalization SRUS method and verify its feasibility in microvascular imaging. METHODS: We introduce a new super-resolution strategy based on the postprocessing of contrast-enhanced ultrasound. The proposed method, which is termed ultrasound diffraction attenuation microscopy (UDAM), uses super-resolution radial fluctuations instead of microbubble localization to overcome acoustic diffraction limits. Biceps of Japanese long-ear white rabbits were adopted to validate its feasibility on muscle vascular imaging, using a clinical accessible ultrasound system at a frame rate of 30 Hz under a single bolus injection of SonoVue (Bracco SpA, Milan, Italy). The super-resolution image was compared with the maximum-intensity projection and ULM. RESULTS: The animal study illustrates that the proposed UDAM can obtain super-resolution microvascular images of rabbits' muscles under a single bolus injection of SonoVue with a 150-second contrast-enhanced ultrasound video. Both ULM and UDAM can achieve a very similar vascular structure with the maximum-intensity projection but much higher spatial resolution. The measurement of 1-dimensional signals shows that UDAM can distinguish the subwavelength structures and substantial reduce the full width at half-maximum of microvessels. CONCLUSIONS: We conclude UDAM provides a noninvasive tool for in vivo super-resolution microvascular imaging.


Assuntos
Microbolhas , Microvasos , Animais , Meios de Contraste , Itália , Microvasos/diagnóstico por imagem , Músculo Esquelético/diagnóstico por imagem , Coelhos , Ultrassonografia
14.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 42(5): 640-645, 2020 Oct.
Artigo em Zh | MEDLINE | ID: mdl-33131519

RESUMO

Objective To explore the value of contrast-enhanced ultrasound(CEUS)in the detection of peripheral nerve crush injury.Methods Thirty New Zealand white rabbits were randomly divided into normal control group and sciatic nerve crush injury group(which included 3-day,2-week,4-week,and 8-week groups after operation).The morphological structure and blood perfusion of the injured sciatic nerves were detected by high-frequency ultrasound,power Doppler ultrasound(PDUS),CEUS,and histopathology.Results Conventional ultrasound revealed that the internal diameter of nerves showed no significant difference between the 8-week group and the control group [(1.14±0.15)mm vs.(0.92±0.11)mm;t=4.72,P=0.86].Analysis of nerve blood perfusion showed that PDUS had a high sensitivity in displaying fine blood flow signal inside the injured nerve in the acute stage of inflammation(3-day group)but not good enough in the 4-and 8-week groups.CEUS could clearly show the microcirculation perfusion in the 3-day,2-week,4-week,and 8-week groups,and analyses of the area under the curve,the peak time,and the peak intensity showed that the nerve blood perfusion increased significantly 3 days after operation and then decreased gradually.Histopathological examination showed that the median cumulative OD value was 12 035.6(10 566.3,14 805.8)8 weeks after operation,which was still significantly lower than that 18 784.8(15 904.5,21 103.5)in the normal control group(H=6.10, P=0.0003).Conclusions Conventional high-frequency ultrasound and PDUS can not adequately evaluate the microcirculation perfusion in different periods after nerve injury.CEUS can quantitatively evaluate the microvascular perfusion of injured nerve at any period and provide more information for indirect evaluation of nerve regeneration.


Assuntos
Meios de Contraste , Lesões por Esmagamento , Traumatismos dos Nervos Periféricos , Ultrassonografia , Animais , Meios de Contraste/normas , Lesões por Esmagamento/diagnóstico por imagem , Microcirculação , Regeneração Nervosa , Traumatismos dos Nervos Periféricos/diagnóstico por imagem , Traumatismos dos Nervos Periféricos/patologia , Coelhos , Distribuição Aleatória , Nervo Isquiático/diagnóstico por imagem , Nervo Isquiático/lesões , Nervo Isquiático/patologia
15.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 42(2): 190-196, 2020 Apr 28.
Artigo em Zh | MEDLINE | ID: mdl-32385024

RESUMO

Objective To explore the value of conventional ultrasound combined with shear-wave elastography in the quantitative evaluation of sciatic nerve crush injury in rabbit models. Methods Forty healthy male New Zealand white rabbits were randomly divided into four groups (n=10 in each group):three crush injury (CI) groups (2,4,and 8 weeks after crush) and control group (without injury). The thickness and stiffness of the crushed sciatic nerves and denervated triceps surae muscles were measured at different time points and compared with histopathologic parameters. Inter-reader variability was assessed with intraclass correlation coefficients. Results Compared with the control group,the inner diameters of the sciatic nerves significantly increased in the 2-week CI group [(1.65±0.34) mm vs. (0.97±0.15) mm,P=0.00] but recovered to the nearly normal level in the 8-week CI group [(1.12±0.18) mm vs. (0.97±0.15) mm,P=0.06];however,compared with control group [(8.75±1.02)kPa],the elastic modulus of the nerves increased significantly in all the CI groups [2-week:(14.77±2.53) kPa;4-week:(19.12±3.46) kPa;and 8-week:(28.39±5.26) kPa;all P=0.00];pathologically,massive hyperplasia of collagen fibers were found in the nerve tissues. The thickness of denervated triceps surae muscle decreased gradually,and the elastic modulus decreased 2 weeks after injury but increased gradually in the following 6 weeks;pathologically,massive hyperplasia of collagen fibers and adipocytes infiltration were visible,along with decreased muscle wet-weight ratio and muscle fiber cross-sectional area. The inter-reader agreements were good. Conclusion Conventional ultrasound combined with shear-wave elastography is feasible for the quantitative evaluation of the morphological and mechanical properties of crushed nerves and denervated muscles.


Assuntos
Lesões por Esmagamento/diagnóstico por imagem , Técnicas de Imagem por Elasticidade , Nervo Isquiático/lesões , Ultrassonografia , Animais , Módulo de Elasticidade , Masculino , Músculo Esquelético/inervação , Músculo Esquelético/patologia , Coelhos , Distribuição Aleatória
16.
Angew Chem Int Ed Engl ; 58(20): 6616-6619, 2019 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-30884078

RESUMO

Spreading depolarization (SD) occurs frequently in the injured brain, and its neurochemical effects are detrimental to brain function. We report the first observation that the release of ascorbate, an important neurochemical in the brain, is closely accompanied with SD. Ascorbate was monitored with carbon nanotube (CNT)-sheathed carbon fiber microelectrodes (CFEs). This system features high selectivity and temporal/spatial resolution. With our sensor, we observed a significant increase in the concentration of ascorbate in response to SD induction. Mechanistic studies show a contrasting behavior; with a SD specific inhibitor, release was completely suppressed, whereas with inhibition of commonly employed glutamate transporters, ascorbate release was increased, demonstrating a powerful means of discriminating ascorbate release between disputed pathways. Most importantly, we observed the propagative nature of ascorbate release following SD.


Assuntos
Encéfalo/fisiopatologia , Técnicas Eletroquímicas/métodos , Animais , Ácido Ascórbico/metabolismo , Ratos
17.
J Cell Mol Med ; 21(1): 4-12, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27785882

RESUMO

Naoxintong (NXT) is a Chinese Materia Medica standardized product extracted from 16 various kinds of Chinese traditional herbal medicines including Salvia miltiorrhiza, Angelica sinensis, Astragali Radix. Naoxintong is clinically effective in treating ischaemia heart disease. Nucleotide-binding oligomerization domain-Like Receptor with a Pyrin domain 3 (NLRP3) inflammasome has been critically involved in myocardial ischaemia/reperfusion (I/R) injury. Here, we have been suggested that NXT might attenuate myocardial I/R injury via suppression of NLRP3 inflammasome activation. Male C57BL6 mice were subjected to myocardial I/R injury via 45 min. coronary ligation and release for the indicated times. Naoxintong (0.7 g/kg/day) and PBS were orally administrated for 2 weeks before surgery. Cardiac function assessed by echocardiography was significantly improved in the NXT group compared to PBS group at day 2 after myocardial I/R. NLRP3 inflammasome activation is crucially involved in the initial inflammatory response after myocardial I/R injury, leading to cleaved caspase-1, mature interleukin (IL)-1ß production, accompanying by macrophage and neutrophil infiltration. The cardioprotective effect of NXT was associated with a diminished NLRP3 inflammasome activation, decreased pro-inflammatory macrophage (M1 macrophages) and neutrophil infiltration after myocardial I/R injury. In addition, serum levels of IL-1ß, indicators of NLRP3 inflammasome activation, were also significantly suppressed in the NXT treated group after I/R injury. Naoxintong exerts cardioprotive effects at least partly by suppression of NLRP3 inflammasome activation in this I/R injury model.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Inflamassomos/efeitos dos fármacos , Inflamassomos/metabolismo , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Traumatismo por Reperfusão/tratamento farmacológico , Animais , Proteínas Reguladoras de Apoptose/metabolismo , Caspase 1/metabolismo , Modelos Animais de Doenças , Interleucina-1beta/sangue , Interleucina-1beta/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Traumatismo por Reperfusão Miocárdica/sangue , Traumatismo por Reperfusão Miocárdica/metabolismo , Infiltração de Neutrófilos/efeitos dos fármacos , Traumatismo por Reperfusão/sangue , Traumatismo por Reperfusão/metabolismo , Transdução de Sinais/efeitos dos fármacos
18.
N Engl J Med ; 370(14): 1327-34, 2014 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-24693892

RESUMO

Gastrointestinal stromal tumors (GISTs) are resistant to traditional chemotherapy but are responsive to the tyrosine kinase inhibitors imatinib and sunitinib. The use of these agents has improved the outcome for patients but is associated with adverse effects, including hypothyroidism. Multiple mechanisms of this effect have been proposed, including decreased iodine organification and glandular capillary regression. Here we report the finding of consumptive hypothyroidism caused by marked overexpression of the thyroid hormone-inactivating enzyme type 3 iodothyronine deiodinase (D3) within the tumor. Affected patients warrant increased monitoring and may require supernormal thyroid hormone supplementation.


Assuntos
Neoplasias Gastrointestinais/enzimologia , Tumores do Estroma Gastrointestinal/enzimologia , Hipotireoidismo/enzimologia , Hipotireoidismo/etiologia , Iodeto Peroxidase/metabolismo , Hormônios Tireóideos/deficiência , Neoplasias Gastrointestinais/complicações , Neoplasias Gastrointestinais/diagnóstico por imagem , Tumores do Estroma Gastrointestinal/complicações , Tumores do Estroma Gastrointestinal/diagnóstico por imagem , Humanos , Iodeto Peroxidase/genética , Masculino , Pessoa de Meia-Idade , Radiografia Abdominal
19.
Med Sci Monit ; 22: 1186-91, 2016 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-27072885

RESUMO

BACKGROUND There has been no published report assessing the mechanical properties of a repaired Achilles tendon after surgery using shear wave elastography (SWE). The aim of this study was to investigate the changes in mechanical properties of the healing Achilles tendon after surgical repair of a tendon rupture using ultrasound SWE and how these changes correlate with tendon function. MATERIAL AND METHODS Twenty-six patients who underwent surgical repair for Achilles tendon rupture were examined with ultrasound SWE coupled with a linear array transducer (4-15 MHz). The elasticity values of the repaired Achilles tendon in a longitudinal view were measured at 12, 24, and 48 weeks postoperatively. Functional outcomes were assessed with the American Orthopedic Foot and Ankle Society (AOFAS) rating system at 12, 24, and 48 weeks postoperatively. General linear regression analysis and correlation coefficients were used to analyze the relationship between elasticity and the AOFAS score. RESULTS There were significant differences with respect to the mean elasticity values and functional scores of the repaired Achilles tendon at 12, 24, and 48 weeks postoperatively (all P<0.05). Tendon function was positively correlated with the elasticity of the repaired Achilles tendon (P=0.0003). CONCLUSIONS Our findings suggest that SWE can provide biomechanical information for evaluating the mechanical properties of healing Achilles tendon and predict Achilles tendon function.


Assuntos
Tendão do Calcâneo/lesões , Tendão do Calcâneo/fisiopatologia , Traumatismos dos Tendões/fisiopatologia , Cicatrização/fisiologia , Tendão do Calcâneo/diagnóstico por imagem , Tendão do Calcâneo/cirurgia , Adulto , Idoso , Módulo de Elasticidade , Técnicas de Imagem por Elasticidade/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos Ortopédicos/métodos , Procedimentos de Cirurgia Plástica/métodos , Ruptura , Traumatismos dos Tendões/diagnóstico por imagem , Traumatismos dos Tendões/cirurgia , Resultado do Tratamento , Ultrassom , Ultrassonografia/métodos
20.
J Phys Ther Sci ; 28(3): 1055-60, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27134411

RESUMO

[Purpose] Ultrasound-guided ilioinguinal/iliohypogastric (II/IH) nerve and transversus abdominis plane (TAP) blocks have been increasingly utilized in patients for perioperative analgesia. We conducted this meta-analysis to evaluate the clinical efficacy of ultrasound-guided II/IH nerve or TAP blocks for perioperative analgesia in patients undergoing open inguinal surgery. [Subjects and Methods] A systematic search was conducted of 7 databases from the inception to March 5, 2015. Randomized controlled trials (RCTs) comparing the clinical efficacy of ultrasound-guided vs. landmark-based techniques to perform II/IH nerve and TAP blocks in patients with open inguinal surgery were included. We constructed random effects models to pool the standardized mean difference (SMD) for continuous outcomes and the odds ratio (OR) for dichotomized outcomes. [Results] Ultrasound-guided II/IH nerve or TAP blocks were associated with a reduced use of intraoperative additional analgesia and a significant reduction of pain scores during day-stay. The use of rescue drugs was also significantly lower in the ultrasound-guided group. [Conclusion] The use of ultrasound-guidance to perform an II/IH nerve or a TAP block was associated with improved perioperative analgesia in patients following open inguinal surgery compared to landmark-based methods.

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