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1.
Cell Biol Int ; 2024 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-39192561

RESUMO

Hepatocellular carcinoma (HCC) is the sixth most common malignant tumor, highlighting a significant need for reliable predictive models to assess clinical prognosis, disease progression, and drug sensitivity. Recent studies have highlighted the critical role of various programmed cell death pathways, including apoptosis, necroptosis, pyroptosis, ferroptosis, cuproptosis, entotic cell death, NETotic cell death, parthanatos, lysosome-dependent cell death, autophagy-dependent cell death, alkaliptosis, oxeiptosis, and disulfidptosis, in tumor development. Therefore, by investigating these pathways, we aimed to develop a predictive model for HCC prognosis and drug sensitivity. We analyzed transcriptome, single-cell transcriptome, genomic, and clinical information using data from the TCGA-LIHC, GSE14520, GSE45436, and GSE166635 datasets. Machine learning algorithms were used to establish a cell death index (CDI) with seven gene signatures, which was validated across three independent datasets, showing that high CDI correlates with poorer prognosis. Unsupervised clustering revealed three molecular subtypes of HCC with distinct biological processes. Furthermore, a nomogram integrating CDI and clinical information demonstrated good predictive performance. CDI was associated with immune checkpoint genes and tumor microenvironment components using single-cell transcriptome analysis. Drug sensitivity analysis indicated that patients with high CDI may be resistant to oxaliplatin and cisplatin but sensitive to axitinib and sorafenib. In summary, our model offers a precise prediction of clinical outcomes and drug sensitivity for patients with HCC, providing valuable insights for personalized treatment strategies.

2.
Mycopathologia ; 188(4): 345-352, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37326820

RESUMO

Candia (Starmera) stellimalicola is a yeast species spread worldwide and recovered from varieties of ecological reservoirs, but human infections are rarely reported. In this study, we reported an intra-abdominal infection case caused by C. stellimalicola and described its microbiological and molecular characteristics. C. stellimalicola strains were isolated from ascites fluid of an 82-year-old male patient having diffuse peritonitis with fever and elevated WBC counts. Routine biochemical and MALDI-TOF MS methods failed to identify the pathogenic strains. Phylogenetic analysis of 18S, 26S and internal transcribed space (ITS) rDNA regions, as well as whole-genome sequence identified the strains as C. stellimalicola. Compared with other Starmera species, C. stellimalicola had unique physiological characteristics including thermal tolerance (able to grow at 42 °C), which may prompt its environmental adaptability and potential for opportunistic human infection. Fluconazole minimum inhibitory concentration (MIC) values of the strains identified in this case was 2 mg/L, and the patient had a favorable outcome after receiving fluconazole treatment. In comparison, the majority of C. stellimalicola strains previously documented had high MIC values (≥ 16 mg/L) to fluconazole. In conclusion, with the raise in human infections caused by rare fungal pathogens, molecular diagnostic remains the most efficient way for accurate species identification; and antifungal susceptibility testing is essential to guide proper patient management.


Assuntos
Micoses , Saccharomycetales , Masculino , Humanos , Idoso de 80 Anos ou mais , Fluconazol/farmacologia , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Candida , Filogenia , Saccharomycetales/genética , Micoses/diagnóstico , Micoses/tratamento farmacológico , Testes de Sensibilidade Microbiana , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos
3.
Plant Foods Hum Nutr ; 77(2): 220-225, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35482150

RESUMO

Pueraria lobata is a perennial legume, commonly used as a food source in China. The polysaccharides extracted from P. lobata have demonstrated various biological activities. However their anti-aging effects and the underline mechanisms are largely unknown. In this study, water-soluble polysaccharides (WSPS) from P. lobata were extracted and demonstrated antioxidant activity against DPPH radicals and hydroxyl radicals in vitro. Using nematode Caenorhabditis elegans as a model, we found that WSPS remarkably prolonged the survival, increased growth and locomotion under heat stress. To investigate the possible mechanism, the levels of reactive oxygen species (ROS) and lipid peroxidation product malondialdehyde (MDA) were determined. WSPS significantly decreased ROS and MDA levels which is consistent with increased activity of superoxide dismutase (SOD). Meanwhile, WSPS upregulated the expression of stress resistance genes sod-1, sod-5, hsf-1, hsp-12.6, hsp-16.2, skn-1 and gst-4. Together, these results suggest that the anti-aging activity of WSPS under heat stress was mediated most likely by activation of the target genes of heat-shock transcription factor (HSF)-1 and skinhead (SKN)-1, and thus inducing endogenous ROS scavenging response.


Assuntos
Caenorhabditis elegans , Pueraria , Envelhecimento , Animais , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Resposta ao Choque Térmico , Longevidade , Estresse Oxidativo , Polissacarídeos/metabolismo , Polissacarídeos/farmacologia , Pueraria/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo , Água
4.
Int J Cancer ; 148(3): 692-701, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-32700765

RESUMO

Although receptor status including estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor 2 (HER2) of the primary breast tumors was related to the prognosis of breast cancer patients, little information is yet available on whether patient management and survival are impacted by receptor conversion in breast cancer metastases. Using data from the nation-wide multicenter clinical epidemiology study of advanced breast cancer in China (NCT03047889), we report the situation of retesting ER, PR and HER2 status for breast cancer metastases and evaluate the patient management and prognostic value of receptor conversion. In total, 3295 patients were analyzed and 1583 (48.0%) patients retesting receptor status for metastasis. Discordance in one or more receptors between the primary and the metastatic biopsy was found in 37.7% of women. Patients who remained hormone receptor (HR) positive in their metastases had similar progression-free survival of first-line and second-line treatment compared to patients with HR conversion (P > .05). In multivariate analysis, patients who showed ER conversion from negative to positive had longer disease-free survival (DFS) than patients who remained negative in their metastases (hazard ratio, 2.05; 95% confidence interval [CI], 1.45-2.90; P < .001). Patients with PR remained positive and had longer DFS than patients with PR conversion from negative to positive (hazard ratio, 0.56; 95% CI, 0.38-0.83; P = .004). Patients with PR conversion have shorter overall survival than patients with PR remained positive or negative (P = .016 and P = .041, respectively). Our findings showed that the receptors' conversions were common in metastatic breast cancer, and the conversion impacted the survival.


Assuntos
Neoplasias da Mama/mortalidade , Receptor ErbB-2/metabolismo , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Neoplasias da Mama/metabolismo , Intervalo Livre de Doença , Estudos Epidemiológicos , Feminino , Humanos , Análise Multivariada , Metástase Neoplásica , Prognóstico , Estudos Retrospectivos
5.
Cell Biol Int ; 44(9): 1881-1889, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32437045

RESUMO

Previous studies have shown that the tumor necrosis factor-α (TNF-α) levels in serum and bone tissues formed in avascular necrosis of femoral head (ANFH) patients were higher than those of normal individuals, indicating TNF-α might play a role in the pathogenesis of ANFH. However, the underlying mechanisms remain unclear. Hematoxylin and eosin staining was performed to show the pathological changes of ANFH bone tissues. TNF-α expression in normal and ANFH tissues was examined by quantitative real-time polymerase chain reaction and western blot analyses. Osteoblast autophagy and apoptosis, as well as signaling pathways activation, were measured by their corresponding marker proteins. Osteoblast proliferation, autophagy, and apoptosis were evaluated using cell counting kit-8, transmission electron microscopy, and flow cytometry. The structures of bone tissues of ANFH were obviously damaged. TNF-α expression was significantly upregulated in ANFH bone tissues compared to normal tissues. Autophagy and apoptosis were remarkably promoted, and p38 mitogen-activated protein kinase (MAPK)/nuclear factor-κB (NF-κB) signaling pathways were markedly activated in ANFH. Suppression of the p38 MAPK/NF-κB pathway significantly attenuated the TNF-α-induced autophagy, however, enhanced the TNF-α-induced apoptosis in osteoblasts. Increased TNF-α in ANFH regulated osteoblast autophagy and apoptosis by p38 MAPK/NF-κB signaling pathways, blocking the pathway by inhibitors exacerbated TNF-α-induced apoptosis through impairing autophagy flux.


Assuntos
Necrose da Cabeça do Fêmur/fisiopatologia , Cabeça do Fêmur/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Adulto , Animais , Apoptose/fisiologia , Autofagia/fisiologia , Feminino , Necrose da Cabeça do Fêmur/metabolismo , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Camundongos , Pessoa de Meia-Idade , Proteínas Quinases Ativadas por Mitógeno/metabolismo , NF-kappa B/metabolismo , Osteoblastos/metabolismo , Transdução de Sinais/genética , Fator de Necrose Tumoral alfa/fisiologia , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
6.
Mycoses ; 63(11): 1235-1243, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33090565

RESUMO

BACKGROUND: In China, the prevalence of superficial fungal infections of the foot is high and recurrence is common. However, a prospective, large-scale and multicentre study on the aetiology of superficial fungal infections of the foot is still lacking. OBJECTIVES: To study the epidemiology of aetiological agents of superficial fungal infections of the foot in urban outpatients in mainland China, as well as to understand the aetiology features of the pathogenic agent. METHODS: The study was designed as a multicentre, prospective epidemiological survey. A total of 1704 subjects were enrolled from seven geographical areas in mainland China. For each subject, one mycological sample and one bacterial sample were collected. KOH wet mount examination and culture were performed at local laboratories. The bacterial results were only reported in those with positive mycology. Further morphological identification and, if necessary, molecular biological identification were conducted in a central laboratory. RESULTS: Of 1704 enrolled subjects, 1327 (77.9%) subjects had positive fungal culture results. The incidence of dermatophytes, yeasts and moulds was 90.1%, 8.1% and 1.1%, respectively. The most frequently isolated aetiological agent (fungus) was Trichophyton rubrum. Moccasin form was the most commonly reported clinical diagnosis of superficial fungal infections. The most frequently isolated bacterial genus in patients was Staphylococcus. CONCLUSION: This study prospectively investigated the clinical and mycological features of human dermatophytosis in mainland China. T rubrum was the most frequently isolated fungus, and moccasin form was the most commonly reported clinical diagnosis of superficial fungal infections.


Assuntos
Dermatomicoses , Pé/microbiologia , Adulto , Arthrodermataceae/isolamento & purificação , Arthrodermataceae/patogenicidade , China/epidemiologia , Dermatomicoses/epidemiologia , Dermatomicoses/etiologia , Dermatomicoses/patologia , Feminino , Pé/patologia , Fungos/isolamento & purificação , Fungos/patogenicidade , Humanos , Incidência , Masculino , Micoses/epidemiologia , Micoses/etiologia , Micoses/patologia , Pacientes Ambulatoriais , Prevalência , Estudos Prospectivos , Leveduras/isolamento & purificação , Leveduras/patogenicidade
7.
J Cell Biochem ; 120(2): 1386-1397, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30450651

RESUMO

Endocrine therapy is one of the main treatments for estrogen receptor-positive breast cancers. Tamoxifen is the most commonly used drug for endocrine therapy. However, primary or acquired tamoxifen resistance occurs in a large proportion of breast cancer patients, leading to therapeutic failure. We found that the combination of tamoxifen and ACT001, a nuclear factor-κB (NF-κB) signaling pathway inhibitor, effectively inhibited the proliferation of both tamoxifen-sensitive and tamoxifen-resistant cells. The tamoxifen-resistant cell line MCF7R/LCC9 showed active NF-κB signaling and high apoptosis-related gene transcription, especially for antiapoptotic genes, which could be diminished by treatment with ACT001. These results demonstrate that ACT001 can prevent and reverse tamoxifen resistance by inhibiting NF-κB activation.

8.
Environ Sci Technol ; 53(5): 2344-2352, 2019 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-30735361

RESUMO

Antagonism between heavy metal and selenium (Se) could significantly affect their biotoxicity, but little is known about the mechanisms underlying such microbial-mediated antagonistic processes as well as the formed products. In this work, we examined the cadmium (Cd)-Se interactions and their fates in Caenorhabditis elegans through in vivo and in vitro analysis and elucidated the machinery of Se-stimulated Cd detoxification. Although the Se introduction induced up to 3-fold higher bioaccumulation of Cd in C. elegans than the Cd-only group, the nematode viability remained at a similar level to the Cd-only group. The relatively lower level of reactive oxygen species in the Se & Cd group confirms a significantly enhanced Cd detoxification by Se. The Cd-Se interaction, mediated by multiple thiols, including glutathione and phytochelatin, resulted in the formation of less toxic cadmium selenide (CdSe)/cadmium sulfide (CdS) nanoparticles. The CdSe/CdS nanoparticles were mainly distributed in the pharynx and intestine of the nematodes, and continuously excreted from the body, which also benefitted the C. elegans survival. Our findings shed new light on the microbial-mediated Cd-Se interactions and may facilitate an improved understanding and control of Cd biotoxicity in complicated coexposure environments.


Assuntos
Nanopartículas , Selênio , Animais , Cádmio , Caenorhabditis elegans , Compostos de Sulfidrila
9.
Cancer Sci ; 108(4): 604-611, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28403546

RESUMO

Delta-aminolevulinate dehydratase (ALAD) catalyzes the second step in the biosynthesis of heme and is also an endogenous inhibitor of the 26S proteasome. The role of ALAD in breast cancer progression is still unclear. In this study, we found that the expression of ALAD was downregulated in breast cancer tissues compared with adjacent normal breast tissues. Enhanced ALAD expression was associated with a favorable outcome in patients with breast cancer. Overexpression of ALAD suppresses breast cancer cell proliferation and invasion and inhibits the epithelial-mesenchymal transition phenotype. Furthermore, we found that ALAD regulates transforming growth factor-ß-mediated breast cancer progression. This finding suggests that ALAD might be a potential biomarker for breast cancer that suppresses breast cancer progression by regulating transforming growth factor-ß-mediated epithelial-mesenchymal transition.


Assuntos
Neoplasias da Mama/genética , Regulação para Baixo , Regulação Neoplásica da Expressão Gênica , Sintase do Porfobilinogênio/genética , Western Blotting , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/enzimologia , Linhagem Celular , Linhagem Celular Tumoral , Proliferação de Células/genética , Progressão da Doença , Transição Epitelial-Mesenquimal/genética , Feminino , Humanos , Microscopia de Fluorescência , Sintase do Porfobilinogênio/metabolismo , Prognóstico , Interferência de RNA , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sensibilidade e Especificidade , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/metabolismo
10.
Molecules ; 21(4): 514, 2016 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-27110751

RESUMO

Recent studies have shown that sulforaphane (SFN) selectively inhibits the growth of ALDH⁺ breast cancer stem-like cells.Herein, a series of SFN analogues were synthesized and evaluated against breast cancer cell lines MCF-7 and SUM-159, and the leukemia stem cell-like cell line KG-1a. These SFN analogues were characterized by the replacement of the methyl group with heterocyclic moieties, and the replacement of the sulfoxide group with sulfide or sulfone. A growth inhibitory assay indicated that the tetrazole analogs 3d, 8d and 9d were significantly more potent than SFN against the three cancer cell lines. Compound 14c, the water soluble derivative of tetrazole sulfide 3d, demonstrated higher potency against KG-1a cell line than 3d. SFN, 3d and 14c significantly induced the activation of caspase-3, and reduced the ALDH⁺ subpopulation in the SUM159 cell line, while the marketed drug doxrubicin(DOX) increased the ALDH⁺ subpopulation.


Assuntos
Ácidos Heterocíclicos/síntese química , Ácidos Heterocíclicos/farmacologia , Anticarcinógenos/síntese química , Anticarcinógenos/farmacologia , Ácidos Heterocíclicos/química , Aldeído Desidrogenase/metabolismo , Anticarcinógenos/química , Caspase 3/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Isotiocianatos/química , Células MCF-7 , Sulfóxidos
11.
Lancet Oncol ; 16(4): 436-46, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25795409

RESUMO

BACKGROUND: Platinum chemotherapy has a role in the treatment of metastatic triple-negative breast cancer but its full potential has probably not yet been reached. We assessed whether a cisplatin plus gemcitabine regimen was non-inferior to or superior to paclitaxel plus gemcitabine as first-line therapy for patients with metastatic triple-negative breast cancer. METHODS: For this open-label, randomised, phase 3, hybrid-designed trial undertaken at 12 institutions or hospitals in China, we included Chinese patients aged 18-70 years with previously untreated, histologically confirmed metastatic triple-negative breast cancer, and an ECOG performance status of 0-1. These patients were randomly assigned (1:1) to receive either cisplatin plus gemcitabine (cisplatin 75 mg/m(2) on day 1 and gemcitabine 1250 mg/m(2) on days 1 and 8) or paclitaxel plus gemcitabine (paclitaxel 175 mg/m(2) on day 1 and gemcitabine 1250 mg/m(2) on days 1 and 8) given intravenously every 3 weeks for a maximum of eight cycles. Randomisation was done centrally via an interactive web response system using block randomisation with a size of eight, with no stratification factors. Patients and investigator were aware of group assignments. The primary endpoint was progression-free survival and analyses were based on all patients who received at least one dose of assigned treatment. The margin used to establish non-inferiority was 1·2. If non-inferiority of cisplatin plus gemcitabine compared with paclitaxel plus gemcitabine was achieved, we would then test for superiority. The trial is registered with ClinicalTrials.gov, number NCT01287624. FINDINGS: From Jan 14, 2011, to Nov 14, 2013, 240 patients were assessed for eligibility and randomly assigned to treatment (120 in the cisplatin plus gemcitabine group and 120 in the paclitaxel plus gemcitabine group). 236 patients received at least one dose of assigned chemotherapy and were included in the modified intention-to-treat analysis (118 per group). After a median follow-up of 16·3 months (IQR 14·4-26·8) in the cisplatin plus gemcitabine group and 15·9 months (10·7-25·4) in the paclitaxel plus gemcitabine group, the hazard ratio for progression-free survival was 0·692 (95% CI 0·523-0·915; pnon-inferiority<0·0001, psuperiority=0·009, thus cisplatin plus gemcitabine was both non-inferior to and superior to paclitaxel plus gemcitabine. Median progression-free survival was 7·73 months (95% CI 6·16-9·30) in the cisplatin plus gemcitabine group and 6·47 months (5·76-7·18) in the paclitaxel plus gemcitabine group. Grade 3 or 4 adverse events that differed significantly between the two groups included nausea (eight [7%] vs one [<1%]), vomiting (13 [11%] vs one [<1%]), musculoskeletal pain (none vs ten [8%]), anaemia (39 [33%] vs six [5%]), and thrombocytopenia (38 [32%] vs three [3%]), for the cisplatin plus gemcitabine compared with the paclitaxel plus gemcitabine groups, respectively. In addition, patients in the cisplatin plus gemcitabine group had significantly fewer events of grade 1-4 alopecia (12 [10%] vs 42 [36%]) and peripheral neuropathy (27 [23%] vs 60 [51%]), but more grade 1-4 anorexia (33 [28%] vs 10 [8%]), constipation (29 [25%] vs 11 [9%]), hypomagnesaemia (27 [23%] vs five [4%]), and hypokalaemia (10 [8%] vs two [2%]). Serious drug-related adverse events were seen in three patients in the paclitaxel plus gemcitabine group (interstitial pneumonia, anaphylaxis, and severe neutropenia) and four in the cisplatin plus gemcitabine group (pathological bone fracture, thrombocytopenia with subcutaneous haemorrhage, severe anaemia, and cardiogenic syncope). There were no treatment-related deaths. INTERPRETATION: Cisplatin plus gemcitabine could be an alternative or even the preferred first-line chemotherapy strategy for patients with metastatic triple-negative breast cancer. FUNDING: Shanghai Natural Science Foundation.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Cisplatino/administração & dosagem , Desoxicitidina/análogos & derivados , Paclitaxel/administração & dosagem , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , China , Cisplatino/efeitos adversos , Desoxicitidina/administração & dosagem , Desoxicitidina/efeitos adversos , Intervalo Livre de Doença , Feminino , Humanos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Paclitaxel/efeitos adversos , Resultado do Tratamento , Neoplasias de Mama Triplo Negativas/patologia , Gencitabina
12.
Ecotoxicology ; 24(10): 2067-72, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26407711

RESUMO

Cu/CuxO nanoparticles (NPs) with different morphologies have been synthesized with glucose as a reducing agent. The X-ray diffraction and Scanning electron microscopy imaging show that the Cu/CuxO NPs have fine crystalline peaks with homogeneous polyhedral, flower-like, and thumbtack-like morphologies. Their antimicrobial activities were evaluated on inactivation of Escherichia coli using a fluorescence-based live/dead staining method. Dissolution of copper ions from these NPs was determined. Results demonstrated a significant growth inhibition for these NPs with different morphologies, and the flower-like Cu/CuxO NPs were the most effective form, where more copper ions were dissolved into the culture media. Surface free energy calculations based on first-principle density functional theory show that different crystal facets of the copper NPs have diverse surface energy, indicating the highest reactivity of the flower-like NPs, which is consistent with the results from the dissolution study and antimicrobial activity test. Together, these results suggest that the difference between the surface free energy may be a cause for their morphology-dependent antimicrobial activity.


Assuntos
Anti-Infecciosos/farmacologia , Cobre/farmacologia , Escherichia coli/efeitos dos fármacos , Nanopartículas Metálicas/análise , Anti-Infecciosos/química , Cobre/química , Escherichia coli/crescimento & desenvolvimento , Escherichia coli/metabolismo , Nanopartículas Metálicas/química
13.
Ecotoxicology ; 24(10): 2175-80, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26410373

RESUMO

Microbial fuel cells (MFCs) have emerged as a promising technology for wastewater treatment with concomitant energy production but the performance is usually limited by low microbial activities. This has spurred intensive research interest for microbial enhancement. This study demonstrated an interesting stimulation effect of a static magnetic field (MF) on sludge-inoculated MFCs and explored into the mechanisms. The implementation of a 100-mT MF accelerated the reactor startup and led to increased electricity generation. Under the MF exposure, the activation loss of the MFC was decreased, but there was no increased secretion of redox mediators. Thus, the MF effect was mainly due to enhanced bioelectrochemical activities of anodic microorganisms, which are likely attributed to the oxidative stress and magnetohydrodynamic effects under an MF exposure. This work implies that weak MF may be applied as a simple and effective approach to stimulate microbial activities for various bioelectrochemical energy production and decontamination applications.


Assuntos
Fontes de Energia Bioelétrica , Biocombustíveis/análise , Campos Magnéticos , Eletricidade
14.
Sheng Li Ke Xue Jin Zhan ; 46(4): 265-8, 2015 Aug.
Artigo em Zh | MEDLINE | ID: mdl-26669077

RESUMO

Necroptosis is a novel programmed cell death mechanism which is caspase independent. It is mediated by specific signaling via a death receptor ligation. Necroptosis usuaUy arises when the apoptotic Pathway is inhibited, and is characterized by a necrotic morphology. Recently many reports have revealed that necroptosis is precisely regulated by a cellular signaling pathway, like apoptosis. Receptor interaction protein kinase 1 and receptor interaction protein kinase 3 kinases are the key regulators of this alternative cell death mechanism. MLKL plays an important role in TNF-induced programmed necrosis pathway. In this paper physiological function and molecular mechanism were reviewed.


Assuntos
Proteínas Quinases/metabolismo , Apoptose , Morte Celular , Necrose , Transdução de Sinais
15.
Sheng Li Ke Xue Jin Zhan ; 46(1): 17-22, 2015 Feb.
Artigo em Zh | MEDLINE | ID: mdl-26103721

RESUMO

Cancer stem cells(CSCs) have been reported in many human tumors and are associated with tumor initiation and progression. CSCs share many biological properties with normal somatic stem cells, such as self-renewal, the propagation of differentiated progeny. However, they also have differences in their chemoresistance and tumorigenic and metastatic activity. CSCs have potential clinical importance, but the regulation at the molecular level is not well-understood. MicroRNAs(miRNAs) are a class of endogenous non-coding RNAs, and play important role in the regulation of several cellular processes. Varieties of evidence show that, miRNAs can regulates the CSCs at a molecular level and are associated with tumor initiation and progression. Better understanding of the regulation of CSCs gene expression by miRNAs could be used to identify the biomarkers and therapeutic targets. In the present review, we summarize the major development on the regulation of CSCs by miRNAs.


Assuntos
Carcinogênese/metabolismo , MicroRNAs/metabolismo , Neoplasias/patologia , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Diferenciação Celular , Humanos
16.
Phys Chem Chem Phys ; 16(42): 23003-11, 2014 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-25238285

RESUMO

The ability of dissimilatory metal-reducing microorganisms (DMRM) to conduct extracellular electron transfer with conductive cellular components grants them great potential for bioenergy and environmental applications. Crystalline Fe(III) oxide, a type of widespread electron acceptor for DMRM in nature, can be excited by light for photocatalysis and microbial culture-mediated photocurrent production. However, the feasibility of direct electron transfer from living cells to light-excited Fe(III) oxides has not been well documented and the cellular physiology in this process has not been clarified. To resolve these problems, an electrochemical system composed of Geobacter sulfurreducens and hematite (α-Fe2O3) was constructed, and direct electron transfer from G. sulfurreducens cells to the light-excited α-Fe2O3 in the absence of soluble electron shuttles was observed. Further studies evidenced the efficient excitation of α-Fe2O3 and the dependence of photocurrent production on the biocatalytic activity. Light-induced electron transfer on the cell-α-Fe2O3 interface correlated linearly with the rates of microbial respiration and substrate consumption. In addition, the G. sulfurreducens cells were found to survive on light-excited α-Fe2O3. These results prove a direct mechanism behind the DMRM respiration driven by photo-induced charge separation in semiconductive acceptors and also imply new opportunities to design photo-bioelectronic devices with living cells as a catalyst.


Assuntos
Biocatálise/efeitos da radiação , Compostos Férricos/química , Compostos Férricos/metabolismo , Geobacter/metabolismo , Geobacter/efeitos da radiação , Luz , Transporte de Elétrons/efeitos da radiação , Geobacter/química , Geobacter/citologia
17.
Acta Pharmacol Sin ; 35(7): 929-36, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24909514

RESUMO

AIM: Receptor-interacting protein 3 (RIP3) is involved in tumor necrosis factor receptor signaling, and results in NF-κB-mediated prosurvival signaling and programmed cell death. The aim of this study was to determine whether overexpression of the RIP3 gene could sensitize human breast cancer cells to parthenolide in vitro. METHODS: The expression of RIP3 mRNA in human breast cancer cell lines (MCF-7, MDA-MB-231, MDA-MB-435 and T47D) was detected using RT-PCR. Both MDA-MB-231 and MCF-7 cells were transfected with RIP3 expression or blank vectors via lentivirus. Cell viability was measured with MTT assay; intracellular ROS level and cell apoptosis were analyzed using flow cytometry. RESULTS: RIP3 mRNA expression was not detected in the four human breast cancer cell lines tested. However, the transfection induced higher levels of RIP3 protein in MCF-7 and MDA-MB-231 cells. Furthermore, overexpression of RIP3 decreased the IC50 values of parthenolide from 17.6 to 12.6 µmol/L in MCF-7 cells, and from 16.6 to 9.9 µmol/L in MDA-MB-231 cells. Moreover, overexpression of RIP3 significantly increased parthenolide-induced apoptosis and ROS accumulation in MCF-7 and MDA-MB-231 cells. Pretreatment with N-acetyl-cysteine abrogated the increased sensitivity of RIP3-transfected MCF-7 and MDA-MB-231 cells to parthenolide. CONCLUSION: Overexpression of RIP3 sensitizes MCF-7 and MDA-MB-231 breast cancer cells to parthenolide in vitro via intracellular ROS accumulation.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Regulação Neoplásica da Expressão Gênica , Proteína Serina-Treonina Quinases de Interação com Receptores/genética , Sesquiterpenos/farmacologia , Apoptose/efeitos dos fármacos , Mama/efeitos dos fármacos , Mama/metabolismo , Mama/patologia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Feminino , Deleção de Genes , Humanos , Espécies Reativas de Oxigênio/metabolismo , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo , Regulação para Cima
18.
Biochem Biophys Res Commun ; 438(2): 433-8, 2013 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-23906755

RESUMO

Neural cell adhesion molecules (CAM) play important roles in the development and regeneration of the nervous system. The L1 family of CAMs is comprised of L1, Close Homolog of L1 (CHL1, L1CAM2), NrCAM, and Neurofascin, which are structurally related trans-membrane proteins in vertebrates. Although the L1CAM has been demonstrated play important role in carcinogenesis and progression, the function of CHL1 in human breast cancer is limited. Here, we found that CHL1 is down-regulated in human breast cancer and related to lower grade. Furthermore, overexpression of CHL1 suppresses proliferation and invasion in MDA-MB-231 cells and knockdown of CHL1 expression results in increased proliferation and invasion in MCF7 cells in vitro. Finally, CHL1 deficiency promotes tumor formation in vivo. Our results may provide a strategy for blocking breast carcinogenesis and progression.


Assuntos
Neoplasias da Mama/metabolismo , Moléculas de Adesão Celular/metabolismo , Regulação Neoplásica da Expressão Gênica , Animais , Biomarcadores Tumorais/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Progressão da Doença , Regulação para Baixo , Feminino , Humanos , Células MCF-7 , Camundongos , Camundongos SCID , Invasividade Neoplásica , Transplante de Neoplasias , RNA Interferente Pequeno/metabolismo , Sais de Tetrazólio/farmacologia , Tiazóis/farmacologia
19.
Guang Pu Xue Yu Guang Pu Fen Xi ; 33(1): 7-13, 2013 Jan.
Artigo em Zh | MEDLINE | ID: mdl-23586213

RESUMO

Spectral distribution of infrared radiation from plume by the method to calculate infrared radiance of the gaze direction in small sight field was calculated. Based on numerical value and form of radiative transfer equation, infrared radiant intensity of the gaze direction was calculated using the Malkmus statistical narrow-band model and CG approach. Flow field and mole fraction distribution were simulated using a FLUENT computational fluid dynamic (CFD) software. Infrared imaging simulation model of hot jet was established. The hot jet's infrared images of liquid rocket engine were generated. The results demonstrate that the method can detect well-resolved fine structure of flow field. And the model is also applicable to calculation and simulation on infrared radiation of hot jet from engine.

20.
Int J Surg ; 109(5): 1318-1329, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-37068793

RESUMO

BACKGROUND: Anastomotic stricture is a common underlying cause of long-term morbidity after hepaticojejunostomy (HJ) for bile duct injury (BDI) following cholecystectomy. However, there are no methods for predicting stricture risk. This study was aimed at establishing two online calculators for predicting anastomotic stricture occurrence (ASO) and stricture-free survival (SFS) in this patient population. METHODS: The clinicopathological characteristics and follow-up information of patients who underwent HJ for BDI after cholecystectomy from a multi-institutional database were reviewed. Univariate and multivariate analyses of the risk factors of ASO and SFS were performed in the training cohort. Two nomogram-based online calculators were developed and validated by internal bootstrapping resamples ( n =1000) and an external cohort. RESULTS: Among 220 screened patients, 41 (18.64%) experienced anastomotic strictures after a median follow-up of 110.7 months. Using multivariate analysis, four variables, including previous repair, sepsis, HJ phase, and bile duct fistula, were identified as independent risk factors associated with both ASO and SFS. Two nomogram models and their corresponding online calculators were subsequently developed. In the training cohort, the novel calculators achieved concordance indices ( C -indices) of 0.841 and 0.763 in predicting ASO and SFS, respectively, much higher than those of the above variables. The predictive accuracy of the resulting models was also good in the internal ( C -indices: 0.867 and 0.821) and external ( C -indices: 0.852 and 0.823) validation cohorts. CONCLUSIONS: The two easy-to-use online calculators demonstrated optimal predictive performance for identifying patients at high risk for ASO and with dismal SFS. The estimation of individual risks will help guide decision-making and long-term personalized surveillance.


Assuntos
Doenças dos Ductos Biliares , Ductos Biliares , Humanos , Ductos Biliares/cirurgia , Ductos Biliares/lesões , Estudos Retrospectivos , Colecistectomia/efeitos adversos , Doenças dos Ductos Biliares/etiologia , Fatores de Risco , Resultado do Tratamento , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/cirurgia
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