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1.
Basic Res Cardiol ; 115(5): 57, 2020 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-32778948

RESUMO

Microvascular damage is a key pathological change in myocardial ischemia/reperfusion (I/R) injury. Using a rat model of myocardial I/R, our current study has provided the first evidence that nicotinamide adenine dinucleotide (NAD+) administration can significantly attenuate myocardial I/R-induced microvascular damage, including reduced regional blood perfusion, decreased microvessel density and integrity, and coronary microvascular endothelial cells (CMECs) injury. In studies with primary cultured CMECs under hypoxia/reoxygenation (HR) and a rat model of I/R, our results suggested that the protective effect of NAD+ on CMECs exposed to HR or I/R is at least partially mediated by the NAD+-induced restoration of autophagic flux, especially lysosomal autophagy: NAD+ treatment markedly induced transcription factor EB (TFEB) activation and attenuated lysosomal dysfunction in the I/R or HR-exposed cells. Collectively, our study has provided the first in vivo and in vitro evidence that NAD+ significantly rescued the impaired autophagic flux and cell apoptosis that was induced by I/R in rat CMECs, which is mediated in part through the action of TFEB-mediated lysosomal autophagy.


Assuntos
Autofagia/efeitos dos fármacos , Traumatismo por Reperfusão Miocárdica/prevenção & controle , NAD/uso terapêutico , Animais , Separação Celular , Avaliação Pré-Clínica de Medicamentos , Endotélio Vascular/citologia , Endotélio Vascular/efeitos dos fármacos , Masculino , Microvasos/efeitos dos fármacos , NAD/farmacologia , Ratos Sprague-Dawley
2.
Cell Physiol Biochem ; 50(2): 768-782, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30308491

RESUMO

BACKGROUND/AIMS: Non-radical primary tumour resection (PTR) of asymptomatic metastatic colorectal cancer (mCRC) can prolong survival time of some patients. Patients with mutated RAS gene have worse survival outcome. This study aimed to investigate the impact of RAS gene mutations on the prognosis of asymptomatic unresectable mCRC patients who underwent PTR. METHODS: A retrospective observational cohort study was deduced among mCRC patients who experienced PTR or had intact primary tumour (IPT). All of them had the primary tumour tissue genotyping tested for RAS (KRAS and NRAS) gene mutations. The tumour-related overall survival (OS) time and progression-free survival (PFS) time was estimated. From January 2011 to June 2014, 421 mCRC patients with asymptomatic, unresectable, metastatic disease were enrolled in this study. Among them, 282 patients underwent PTR and 139 patients had IPT. RESULTS: The mutation rate of RAS was 53.8% (221/411). With a median followed-up time of 46.5 months, the overall survival time of mCRC patients harboring wtRAS or mtRAS was 28.0 versus 22.0 months (p = 0.043) in PTR group and was 21.6 versus 17.8 months (p=0.071) in IPT groups. A Multivariate regression analysis suggested that RAS gene (p=0.039, HR=1.288,95%CI [1.072∼2.911]), metastatic organ number (p=0.033, HR=3.091,95%CI [1.090∼5.755]) and systemic therapy response (p=0.019, HR=0.622,95%CI [0.525∼0.811]) were independent prognostic factors in PTR population. CONCLUSION: We found that wild-type RAS gene was a favorable factor for the asymptomatic unresectable mCRC patients experiencing PTR.


Assuntos
Neoplasias Colorretais/patologia , Proteínas ras/genética , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/mortalidade , Intervalo Livre de Doença , Feminino , Genótipo , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Mutação , Metástase Neoplásica , Prognóstico , Modelos de Riscos Proporcionais , Análise de Regressão , Estudos Retrospectivos
3.
J Stomatol Oral Maxillofac Surg ; : 102046, 2024 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-39251069

RESUMO

Gingival squamous cell carcinoma (SCC) of the posterior mandible often requires marginal resection of the mandible in conventional surgery. However, the posterior location of the lesion can limit surgical visibility, which is critical for complete tumor removal and minimizing recurrence. Typically, marginal resection of the posterior mandible is achieved through a midline lower lip incision and mental nerve transection, providing adequate exposure but resulting in nerve damage, lip numbness, and facial scarring. In this paper, we describe a case using a submandibular incision for neck dissection, extending from the mandibular angle to the mental foramen, to fully expose the posterior mandible. The intraoral incision, extending 1 cm beyond the tumor margin, connected with the submandibular incision. Under direct vision, we performed a marginal resection of the mandible, preserving the inferior alveolar neurovascular bundle and the mental nerve, and maintaining at least 1 cm of the inferior mandibular margin. This technique achieved complete tumor removal while preserving mental nerve function and lower lip integrity, reducing surgical difficulty and patient trauma. This approach maintains nerve function and aesthetics as much as possible, with a faster postoperative recovery. In treating gingival SCC of the posterior mandible, it is essential to preserve surrounding healthy tissue and critical anatomical structures, minimizing postoperative complications while ensuring complete tumor resection.

4.
Adv Sci (Weinh) ; 11(32): e2402740, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38899849

RESUMO

Amyloid polymorphism is a hallmark of almost all amyloid species, yet the mechanisms underlying the formation of amyloid polymorphs and their complex architectures remain elusive. Commonly, two main mesoscopic topologies are found in amyloid polymorphs characterized by non-zero Gaussian and mean curvatures: twisted ribbons and helical fibrils, respectively. Here, a rich heterogeneity of configurations is demonstrated on insulin amyloid fibrils, where protofilament packing can occur, besides the common polymorphs, also in a combined mode forming mixed-curvature polymorphs. Through AFM statistical analysis, an extended array of heterogeneous architectures that are rationalized by mesoscopic theoretical arguments are identified. Notably, an unusual fibrillization pathway is also unraveled toward mixed-curvature polymorphs via the widespread recruitment and intertwining of protofilaments and protofibrils. The results present an original view of amyloid polymorphism and advance the fundamental understanding of the fibrillization mechanism from single protofilaments into mature amyloid fibrils.


Assuntos
Amiloide , Amiloide/química , Amiloide/metabolismo , Microscopia de Força Atômica/métodos , Insulina/química , Insulina/metabolismo , Insulina/genética
5.
J Cancer ; 14(8): 1321-1334, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37283792

RESUMO

Tumor tissues consist of tumor cells and tumor stroma, which is structured by non-tumor cells and the extracellular matrix. Macrophages are the predominant immune cells in the tumor microenvironment (TME). Based on the intimate interaction between macrophages and tumor cells, macrophages are closely involved in tumor initiation and progression, playing a key role in tumor formation, angiogenesis, metastasis, and immune escape. Extracellular vesicles (EVs) are a group of membrane-enclosed structures secreted by almost all cell types. As crucial mediators of cell-to-cell communication, EVs play a role in various physiological processes and the development of diseases including cancer. According to numerous studies, tumor cell-derived extracellular vesicles (T-EVs) could highly modulate the phenotypes and functions of macrophages, thus promoting tumor development. Herein, we comprehensively introduce the role of T-EVs in regulating the M1/M2 phenotypes and immune functions of macrophages, including cytokine secretion, expression of immune regulatory molecules on the membrane, phagocytosis, and antigen presentation. More importantly, based on the regulatory effects of T-EVs on macrophages, we propose several potential therapeutic approaches that may guide future attempts to increase the effectiveness of cancer therapy.

6.
Cancers (Basel) ; 15(10)2023 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-37345054

RESUMO

Macrophages are essential for the human body in both physiological and pathological conditions, engulfing undesirable substances and participating in several processes, such as organism growth, immune regulation, and maintenance of homeostasis. Macrophages play an important role in anti-bacterial and anti-tumoral responses. Aberrance in the phagocytosis of macrophages may lead to the development of several diseases, including tumors. Tumor cells can evade the phagocytosis of macrophages, and "educate" macrophages to become pro-tumoral, resulting in the reduced phagocytosis of macrophages. Hence, harnessing the phagocytosis of macrophages is an important approach to bolster the efficacy of anti-tumor treatment. In this review, we elucidated the underlying phagocytosis mechanisms, such as the equilibrium among phagocytic signals, receptors and their respective signaling pathways, macrophage activation, as well as mitochondrial fission. We also reviewed the recent progress in the area of application strategies on the basis of the phagocytosis mechanism, including strategies targeting the phagocytic signals, antibody-dependent cellular phagocytosis (ADCP), and macrophage activators. We also covered recent studies of Chimeric Antigen Receptor Macrophage (CAR-M)-based anti-tumor therapy. Furthermore, we summarized the shortcomings and future applications of each strategy and look into their prospects with the hope of providing future research directions for developing the application of macrophage phagocytosis-promoting therapy.

7.
Front Bioeng Biotechnol ; 10: 1016598, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36246357

RESUMO

Although intelligent technologies has facilitated the development of precise orthopaedic, simple internal fixation, ligament reconstruction or arthroplasty can only relieve pain of patients in short-term. To achieve the best recover of musculoskeletal injuries, three bottlenecks must be broken through, which includes scientific path planning, bioactive implants and personalized surgical channels building. As scientific surgical path can be planned and built by through AI technology, 4D printing technology can make more bioactive implants be manufactured, and variable structures can establish personalized channels precisely, it is possible to achieve satisfied and effective musculoskeletal injury recovery with the progress of multi-layer intelligent technologies (MLIT).

8.
Nat Commun ; 12(1): 6635, 2021 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-34789727

RESUMO

Pupylation is the post-translational modification of lysine side chains with prokaryotic ubiquitin-like protein (Pup) that targets proteins for proteasomal degradation in mycobacteria and other members of Actinobacteria. Pup ligase PafA and depupylase Dop are the two enzymes acting in this pathway. Although they share close structural and sequence homology indicative of a common evolutionary origin, they catalyze opposing reactions. Here, we report a series of high-resolution crystal structures of Dop in different functional states along the reaction pathway, including Pup-bound states in distinct conformations. In combination with biochemical analysis, the structures explain the role of the C-terminal residue of Pup in ATP hydrolysis, the process that generates the catalytic phosphate in the active site, and suggest a role for the Dop-loop as an allosteric sensor for Pup-binding and ATP cleavage.


Assuntos
Amidoidrolases/química , Proteínas de Bactérias/química , Fosfatos/química , Ubiquitinas/química , Trifosfato de Adenosina/química , Trifosfato de Adenosina/metabolismo , Regulação Alostérica , Amidoidrolases/metabolismo , Proteínas de Bactérias/metabolismo , Catálise , Domínio Catalítico , Cristalografia por Raios X , Ligação de Hidrogênio , Hidrólise , Modelos Moleculares , Fosfatos/metabolismo , Conformação Proteica , Processamento de Proteína Pós-Traducional , Ubiquitinas/metabolismo
9.
Can J Cardiol ; 36(4): 589.e5-589.e7, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32220388

RESUMO

We report an interesting case of coronary arteritis and periaortitis in a 62-year-old man with a history of biopsy-proven IgG4-related pulmonary disease. After 2 years of immune-suppressive therapy, the perivascular tissue surrounding all coronary arteries and the abdominal aorta was significantly attenuated, except that the luminal stenosis was aggravated to 70% in the left anterior descending coronary artery. Treatment with aspirin, atorvastatin, and ezetimibe was added. The patient was discharged under strict lesion surveillance at follow-up.


Assuntos
Aortite/imunologia , Arterite/imunologia , Doença da Artéria Coronariana/imunologia , Doença Relacionada a Imunoglobulina G4/complicações , Humanos , Masculino , Pessoa de Meia-Idade
10.
Oncotarget ; 7(49): 80888-80900, 2016 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-27825133

RESUMO

Resistance to epidermal growth factor receptor (EGFR) targeted monoclonal antibody therapy represents a clinical challenge in patients suffered from RAS wild-type (WT) metastatic colorectal cancer (mCRC). However, the molecular mechanisms and key factors conferring this resistance are largely unknown. Forkhead transcription factors of the O class 3a (FoxO3a), an important regulator of cell survival, has been reported with dual functions in tumor recently. In this study, we found that FoxO3a was highly expressed in cetuximab resistant CRC tissues compared with cetuximab sensitive tissues. We therefore further analyzed its function in induced cetuximab resistant RAS-WT CRC cells (Caco2-CR) and intrinsic resistant cells with BRAF mutation (HT29). We found that FoxO3a was significantly up-regulated in Caco2-CR as well as in cetuximab treated HT29 cells. Knockdown of FoxO3a could sensitize these cells to cetuximab treatment with reduced cell proliferation and migration ability. Further, biochemical experiments demonstrated that FoxO3a directly bind to c-Myc promoter and activated the transcription of the c-Myc gene, thus participated in regulating of c-Myc downstream genes, including ACO2, LARS2, MRPL12 and PKM2 in these resistant cells. Moreover, knockdown of c-Myc elevated cell apoptosis to cetuximab treatment and suppressed cell proliferation and migration ability consistently. Altogether, our study indicates that FoxO3a might be a key regulator in cetuximab resistance through up-regulating c-Myc in colorectal cancer targeted therapy.


Assuntos
Antineoplásicos Imunológicos/farmacologia , Movimento Celular , Cetuximab/farmacologia , Neoplasias Colorretais/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos , Proteína Forkhead Box O3/metabolismo , Genes ras , Proteínas Proto-Oncogênicas c-myc/metabolismo , Animais , Apoptose/efeitos dos fármacos , Sítios de Ligação , Células CACO-2 , Proliferação de Células/efeitos dos fármacos , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Resistencia a Medicamentos Antineoplásicos/genética , Proteína Forkhead Box O3/genética , Regulação Neoplásica da Expressão Gênica , Células HT29 , Humanos , Camundongos Nus , Mutação , Invasividade Neoplásica , Regiões Promotoras Genéticas , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas c-myc/genética , Interferência de RNA , Transdução de Sinais , Fatores de Tempo , Transcrição Gênica , Transfecção , Carga Tumoral/efeitos dos fármacos
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