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1.
J Asian Nat Prod Res ; : 1-7, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38945154

RESUMO

A new steroid, 2a-oxa-2-oxo-5ß-hydroxy-3,4-dinor-24-methylcholesta-22E-ene (1), together with 10 known ones (2-11), was isolated from the marine sponge Cliona sp. The structures of these compounds were determined by the spectroscopic methods (UV, IR, MS, and NMR) and X-ray diffraction analysis. Compound 1 was the third example of 3,4-dinorsteroid with a hemiketal at C-5 that was isolated from the natural source. In addition, the antibacterial activities of these compounds were also evaluated. However, none of them exhibited significant inhibition effects.

2.
J Viral Hepat ; 30(12): 951-958, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37735836

RESUMO

The HBV rtA181T mutation is associated with an increased risk of hepatocellular carcinoma (HCC) in patients with chronic hepatitis B (CHB). This study aimed to evaluate the mechanism by which rtA181T mutation increases the risk of HCC. We enrolled 470 CHB patients with rtA181T and rtA181V mutation in this study; 68 (22.15%) of the 307 patients with rtA181T mutation and 22 (13.5%) of the 163 patients with rtA181V mutation developed HCC (p < .05). The median follow-up periods were 8.148 and 8.055 years (p > .05). Serum HBV DNA and HBsAg levels in rtA181T-positive patients were similar to that in rtA181V-positive patients. However, the serum HBeAg levels in the rtA181T-positive patients were significantly higher than that in rtA181V-positive patients. In situ hybridization experiments showed that the HBV cccDNA and HBV RNA levels were significantly higher in the liver cancer tissues of patients with the rtA181T mutation compared to that in the tissues of patients with the rtA181V mutation. The percentage of anti-tumour hot-gene site mutations was significantly higher in the rtA181T-positive HCC liver tissue compared to that in the rtA181T-negative HCC liver tissue (7.65% and 4.3%, p < .05). This is the first study to use a large cohort and a follow-up of more than 5 years (average 8 years) to confirm that the rtA181T mutation increased the risk of HCC, and that it could be related to the increase in the mutation rate of hotspots of tumour suppressor genes (CTNNB1, TP53, NRAS and PIK3CA).


Assuntos
Carcinoma Hepatocelular , Hepatite B Crônica , Neoplasias Hepáticas , Humanos , Vírus da Hepatite B/genética , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/tratamento farmacológico , Hepatite B Crônica/tratamento farmacológico , Antivirais/uso terapêutico , Taxa de Mutação , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/tratamento farmacológico , Mutação , Genes Supressores de Tumor , DNA Viral/genética , Antígenos de Superfície da Hepatite B/genética
4.
Nat Protoc ; 18(6): 1712-1744, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37248393

RESUMO

Ultraflexible microelectrode arrays (MEAs) that can stably record from a large number of neurons after their chronic implantation offer opportunities for understanding neural circuit mechanisms and developing next-generation brain-computer interfaces. The implementation of ultraflexible MEAs requires their reliable implantation into deep brain tissues in a minimally invasive manner, as well as their precise integration with optogenetic tools to enable the simultaneous recording of neural activity and neuromodulation. Here, we describe the process for the preparation of elastocapillary self-assembled ultraflexible MEAs, their use in combination with adeno-associated virus vectors carrying opsin genes and promoters to form an optrode probe and their in vivo experimental use in the brains of rodents, enabling electrophysiological recordings and optical modulation of neuronal activity over long periods of time (on the order of weeks to months). The procedures, including device fabrication, probe assembly and implantation, can be completed within 3 weeks. The protocol is intended to facilitate the applications of ultraflexible MEAs for long-term neuronal activity recording and combined electrophysiology and optogenetics. The protocol requires users with expertise in clean room facilities for the fabrication of ultraflexible MEAs.


Assuntos
Microeletrodos , Optogenética , Neurônios
5.
Cell Death Discov ; 9(1): 42, 2023 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-36732504

RESUMO

Resistance to radiotherapy remains a major unmet clinical obstacle in the treatment of locally advanced rectal cancer. Cancer stem cells (CSCs) are considered to mediate tumor development and radioresistance. However, the role of CSCs in regulating resistance to radiotherapy in colorectal cancer (CRC) remains largely unknown. We established two radioresistant CRC cell lines, HCT116-R and RKO-R, using fractionated irradiation. Analysis using miRNA sequencing and quantitative real-time PCR confirmed lower levels of miR-7-5p in both of the radioresistant cells compared to their parental cells. Subsequently, we validated that miR-7-5p expression was decreased in cancerous tissues from radiotherapy-resistant rectal cancer patients. The Cancer Genome Atlas (TCGA) database analyses revealed that low miR-7-5p expression was significantly correlated with poor prognosis in CRC patients. Overexpression of miR-7-5p led to a rescue of radioresistance and an increase in radiation-induced apoptosis, and attenuated the stem cell-like properties in HCT116-R and RKO-R cells. Conversely, knocking down miR-7-5p in parental HCT116 and RKO cells suppressed the sensitivity to radiation treatment and enhance cancer cell stemness. Stemness-associated transcription factor KLF4 was demonstrated as a target of miR-7-5p. Rescue experiments revealed that miR-7-5p/KLF4 axis could induce radiosensitivity by regulating CSCs in colorectal cancer cells. Furthermore, we used CRC tumor tissues which exhibited resistance to neoadjuvant radiotherapy to establish a patient-derived xenograft (PDX) mouse model. Tail vein injection of magnetic nanoparticles carrying miR-7-5p mimics into the PDX mice significantly inhibited tumor growth with or without irradiation treatment in vivo. Our current studies not only demonstrate an anti-cancer function of miR-7-5p in regulating CSC properties and radiosensitivity in colorectal cancer, but also provide a novel potential strategy for delaying or reverse radiation resistance in preoperative radiotherapy of CRC patients.

6.
Front Immunol ; 13: 954177, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36189318

RESUMO

SARS-CoV-2 vaccination has been recommended for liver transplant (LT) recipients. However, our understanding of inactivated vaccine stimulation of the immune system in regulating humoral and cellular immunity among LT recipients is inadequate. Forty-six LT recipients who received two-dose inactivated vaccines according to the national vaccination schedule were enrolled. The clinical characteristics, antibody responses, single-cell peripheral immune profiling, and plasma cytokine/chemokine/growth factor levels were recorded. Sixteen (34.78%) LT recipients with positive neutralizing antibody (nAb) were present in the Type 1 group. Fourteen and 16 LT recipients with undetected nAb were present in the Type 2 and Type 3 groups, respectively. Time from transplant and lymphocyte count were different among the three groups. The levels of anti-RBD and anti-S1S2 decreased with decreasing neutralizing inhibition rates. Compared to the Type 2 and Type 3 groups, the Type 1 group had an enhanced innate immune response. The proportions of B, DNT, and CD3+CD19+ cells were increased in the Type 1 group, whereas monocytes and CD4+ T cells were decreased. High CD19, high CD8+CD45RA+ cells, and low effector memory CD4+/naïve CD4+ cells of the T-cell populations were present in the Type 1 group. The Type 1 group had higher concentrations of plasma CXCL10, MIP-1 beta, and TNF-alpha. No severe adverse events were reported in all LT recipients. We identified the immune responses induced by inactivated vaccines among LT recipients and provided insights into the identification of immunotypes associated with the responders.


Assuntos
COVID-19 , Transplante de Fígado , Vacinas Virais , Anticorpos Neutralizantes , Formação de Anticorpos , COVID-19/prevenção & controle , Vacinas contra COVID-19 , Humanos , SARS-CoV-2 , Fator de Necrose Tumoral alfa , Vacinas de Produtos Inativados
7.
Front Immunol ; 13: 995223, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36159788

RESUMO

Background: In primary biliary cholangitis (PBC), the levels of serum IL-2 were involved in liver inflammation and immune changes. This study aimed to investigate the prognostic significance of serum IL-2 combined with total bilirubin (TBIL) in liver failure and cytokine changes during the disease. Methods: A total of 160 PBC patients treated with UDCA were included. Parameters at admission were collected, and the COX regression model was used to predict independent risk factors associated with PBC disease progression. We identified the optimal cut-off values and prognosis effects of serum IL-2 and TBIL based on the time-dependent receiver operating characteristic (ROC) curve. We also analyzed the incidence of liver failure with Kaplan-Meier survival analysis. In addition, the changes of cytokines (mainly IL-2) in liver tissues and blood samples from 11 patients with end-stage PBC liver failure and five healthy controls were examined. Results: Age, IL-2, ALB, γ-GT, ALP, TBIL, Hb, TBA, WBC, and PLT, as well as anti-Sp100, were found to be independent risk factors in PBC patients with liver failure. Patients with decreased serum IL-2 levels and increased TBIL levels have a significantly higher incidence of liver failure and a worse prognosis. Patients with advanced PBC liver failure after liver transplantation exhibited a significant decrease in levels of serum IL-2 and a relatively immunosuppressed status. Conclusions: The combination of serum IL-2 and TBIL can be a predictor of the progression of liver failure in patients with primary biliary cholangitis, and it is likely to be related to the expression of GM-CSF and G-CSF.


Assuntos
Cirrose Hepática Biliar , Falência Hepática , Bilirrubina , Fator Estimulador de Colônias de Granulócitos , Fator Estimulador de Colônias de Granulócitos e Macrófagos , Humanos , Interleucina-2 , Cirrose Hepática Biliar/complicações , Falência Hepática/etiologia , Prognóstico
8.
Adv Mater ; 34(5): e2107343, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34796566

RESUMO

Flexible neural electrodes integrated on micrometer-thick polymer substrates offer important opportunities for improving the stability of neuronal activity recordings during cognitive processes. However, the bending stiffness of micrometer-thick polymer substrates is typically two orders of magnitude higher than that of nanofilm electrodes, making it a limiting factor in electrode-tissue interfacings. Here, this limitation is overcome by developing self-assembled nanofilm electrode arrays (NEAs) that consist of high-density, free-standing gold nanofilm electrodes. Chronically implanted NEAs can form intimate and innervated interfaces with neural tissue, enabling stable neuronal activity recordings across multiple brain regions over several months. As an application example, the activities of the same neuronal populations are tracked across odor discrimination reversal learning and it is illustrated how dorsal striatal neurons represent and update stimulus-outcome associations across multiple timescales. The results underscore the potential of free-standing nanoscale materials for interfacing biological systems over long terms.


Assuntos
Encéfalo , Neurônios , Encéfalo/fisiologia , Eletrodos Implantados , Microeletrodos , Neurônios/fisiologia , Polímeros
9.
J Gastroenterol Hepatol ; 36(7): 1803-1811, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33150976

RESUMO

BACKGROUND AND AIM: The goal of this study was to develop a preoperative nomogram for predicting the feasibility of trans-anal natural orifice specimen extraction (NOSE) for rectal cancer. METHODS: The analysis included 201 patients who underwent trans-anal NOSE and 457 patients who failed to undergo trans-anal NOSE in Shanghai East Hospital. The data collected included age, gender, body mass index, presence of tumor obstruction, distance from anal verge; maximum tumor diameter and anteroposterior thickness of mesorectum (AP) measured by magnetic resonance imaging; interspinous diameter, intertuberous diameter (IT), anteroposterior diameter of the inlet (API), anteroposterior diameter of the midplane, anteroposterior diameter of the outlet (APO), sacral length and pelvic depth (PD) measured by computed tomography. RESULTS: The multivariate analysis suggested that a lower body mass index (P < 0.001), no tumor obstruction (P = 0.005), a shorter distance from anal verge (P < 0.001), a smaller tumor size (P < 0.001), a thinner AP (P < 0.001), a wider and shallower bony pelvis (API/PD, P < 0.001), and a wider and shorter pelvic outlet (IT/APO, P < 0.001) were significantly associated with an increased probability of trans-anal NOSE. Successful NOSE patients had a decreased time to liquid intake (P < 0.001), a shorter postoperative hospital stay (P < 0.001), and fewer wound infections (P = 0.045). No significant difference in the rate of mortality or recurrence was observed. The nomogram model presented an area under the receiver operating characteristic curve of 0.81 (95% CI, 0.78 to 0.85) and good calibration. CONCLUSION: We developed a nomogram model that has some predicative value for the feasibility of laparoscopic rectal resection with trans-anal NOSE, utilizing clinical and radiologic parameters, available in most institutions.


Assuntos
Laparoscopia , Cirurgia Endoscópica por Orifício Natural , Nomogramas , Neoplasias Retais/cirurgia , Manejo de Espécimes , Canal Anal , China , Dissecação , Estudos de Viabilidade , Humanos , Seleção de Pacientes
10.
Mol Biol Rep ; 47(11): 8439-8450, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33021719

RESUMO

The role of the Notch signaling pathway in adipogenesis has long been controversial as the action of individual Notch receptors appears to vary with experimental conditions. In this study, we offer some explanation for the observed contradictions by comparing the role of both Notch1 and Notch3 in regulating the expression of key adipogenic regulator, PPARγ, in human adipose-derived stem/stromal cells (hADSCs) during in vitro adipogenesis. Utilizing qRT-PCR, western blot, and immunofluorescence staining, we demonstrated that Notch3 was expressed prior to the formation of lipid vesicles, while Notch1 only appeared after vesicle formation. In addition, following the induction of adipogenesis, the levels of Notch1 intracellular domain in the nucleus were significantly reduced, while the siRNA-mediated loss of Notch1 reduced transcript but not protein levels of PPARγ. The knockdown of Notch3 led to increased expression of PPARγ during early adipogenesis that was not paralleled by a decreased expression of Hes1 and Hey1, but was accompanied by a marked decrease in the protein level of ß-catenin, the key functional component of the canonical Wnt/ß-catenin signaling pathway. This study deepens the understanding of the Notch pathway by clarifying the distinct roles of Notch1 and Notch3 during adipogenesis. We showed that Notch3 is involved in early adipogenic differentiation, while Notch1 functions later in the process. In addition, we begin to uncover the interaction between the Notch and Wnt signaling pathways that may offer novel therapeutic targets aimed at obesity and diabetes.


Assuntos
Adipogenia/genética , Tecido Adiposo/citologia , Receptor Notch1/genética , Receptor Notch3/genética , Células Estromais/metabolismo , Diferenciação Celular/genética , Núcleo Celular/genética , Núcleo Celular/metabolismo , Células Cultivadas , Regulação da Expressão Gênica , Humanos , PPAR gama/genética , PPAR gama/metabolismo , Interferência de RNA , Receptor Notch1/metabolismo , Receptor Notch3/metabolismo , Transdução de Sinais/genética , Via de Sinalização Wnt/genética
11.
Acta Vet Scand ; 60(1): 53, 2018 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-30208923

RESUMO

BACKGROUND: Trueperella pyogenes is a commensal and a significant opportunistic pathogen in animals. A variety of identified or putative virulence factors are considered to significantly contribute to the occurrence of T. pyogenes infection in different species. However, these virulence factors are not fully understood. RESULTS: In the current study, the genes encoding putative fimbrial proteins, i.e. Fim A, Fim C, and Fim E, were cloned. Recombinant Fim A (rFim A), Fim C (rFim C), and Fim E (rFim E) were prepared and used to generate rabbit anti-rFim A, anti-rFim C, and anti-rFim E serum, respectively. Using these sera, we found that only Fim E was constitutively expressed in T. pyogenes. The expression level of Fim E in T. pyogenes peaked within 6-10 h of culture period in pH 7.5. Fim E protein expression was unaffected by anaerobic condition, but was inhibited by the microaerophilic condition. Tube agglutination tests indicated that Fim E was exhibited on the surface of T. pyogenes cells because anti-rFim E serum caused strong agglutination. Additionally, the blots for Fim A detection showed nonspecific reactions. Furthermore, the tube agglutination tests showed that anti-Fim A serum failed to cause agglutination of T. pyogenes cells, which indicated that Fim A was not, or poorly, expressed in cultured T. pyogenes. Anti-rFim C serum caused strong agglutination. However, the blots for Fim C detection showed a strong nonspecific reaction. Thus, the expression of Fim C was difficult to be determined using the current method. CONCLUSIONS: Fim E was expressed in cultured T. pyogenes. However, Fim A was either not or poorly expressed in cultured T. pyogenes. Moreover, Fim C expression was not determined using the current strategy.


Assuntos
Actinomycetaceae/genética , Proteínas de Fímbrias/genética , Regulação Bacteriana da Expressão Gênica , Actinomycetaceae/crescimento & desenvolvimento , Perfilação da Expressão Gênica
12.
Biochimie ; 150: 31-36, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29709509

RESUMO

Human adipose-derived stromal/stem cells (hASCs) have tremendous therapeutic potential and the ability to offer insight into human development and disease. Here we subject human ASCs to siRNA-mediated knockdown of Notch3 cultured under both self-renewing and adipogenic differentiation conditions. Self-renewal was monitored by assessing viability and proliferation rates through staining and alamarBlue assays, respectively. Adipogenesis was measured through Oil-Red O staining, western blot, and quantitative real-time RT-PCR that determined expression levels of multipotency and adipogenic markers over time. Notch3 was expressed in self-renewing hASCs but knockdown, as validated by qRT-PCR and western blot, showed no impact on cell viability, as measured through live-dead staining, or cell proliferation rates, as measured through alamarBlue assays. However, although Notch3 expression was observed to increase during adipogenesis, in the absence of Notch3 there was a significant increase in hASC adipogenesis as demonstrated through an increased number of lipid vesicles, and increased expression of adipogenic markers ppar-γ, adiponectin, fabp4, and plin2. Although Notch3 is only one of four Notch receptors expressed on the surface of hASCs, this receptor appears important for proper regulation of adipogenic differentiation, possibly serving as a negative regulator to prevent inappropriate adipogenesis or promote other lineage commitments of ASCs.


Assuntos
Adipogenia/fisiologia , Tecido Adiposo/citologia , Receptor Notch3/metabolismo , Células-Tronco/citologia , Células-Tronco/metabolismo , Adipócitos/citologia , Adipócitos/metabolismo , Adipogenia/genética , Western Blotting , Diferenciação Celular/genética , Diferenciação Celular/fisiologia , Proliferação de Células/genética , Proliferação de Células/fisiologia , Sobrevivência Celular/genética , Sobrevivência Celular/fisiologia , Células Cultivadas , Humanos , Receptor Notch3/genética , Receptores Notch/metabolismo , Transdução de Sinais/genética , Transdução de Sinais/fisiologia
13.
Acta Vet Hung ; 65(3): 327-339, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28956490

RESUMO

Pasteurella multocida, Mannheimia haemolytica and Trueperella pyogenes are three bacterial pathogens closely associated with the bovine respiratory disease complex (BRDC). In the current study, a multiplex PCR for the simultaneous detection of these three bacteria in cultures was established. After serial optimisation, the detection limit of the method for the genomic DNA of the three bacteria was 40 pg/µl. The method could detect the genomic DNA of these three bacteria but not the genomic DNA of seven other bacterial strains. Together with the bacterial enrichment technology, the multiplex PCR could be used for detecting the three bacteria in animal tissues. This method might be valuable for speeding up laboratory diagnosis and directing the treatment of BRDC to these three bacterial pathogens.


Assuntos
Actinomycetaceae/isolamento & purificação , Mannheimia haemolytica/isolamento & purificação , Reação em Cadeia da Polimerase Multiplex/métodos , Pasteurella multocida/isolamento & purificação , Sensibilidade e Especificidade
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