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1.
Proc Natl Acad Sci U S A ; 121(28): e2322972121, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38968116

RESUMO

Rapid accumulation of repair factors at DNA double-strand breaks (DSBs) is essential for DSB repair. Several factors involved in DSB repair have been found undergoing liquid-liquid phase separation (LLPS) at DSB sites to facilitate DNA repair. RNF168, a RING-type E3 ubiquitin ligase, catalyzes H2A.X ubiquitination for recruiting DNA repair factors. Yet, whether RNF168 undergoes LLPS at DSB sites remains unclear. Here, we identified K63-linked polyubiquitin-triggered RNF168 condensation which further promoted RNF168-mediated DSB repair. RNF168 formed liquid-like condensates upon irradiation in the nucleus while purified RNF168 protein also condensed in vitro. An intrinsically disordered region containing amino acids 460-550 was identified as the essential domain for RNF168 condensation. Interestingly, LLPS of RNF168 was significantly enhanced by K63-linked polyubiquitin chains, and LLPS largely enhanced the RNF168-mediated H2A.X ubiquitination, suggesting a positive feedback loop to facilitate RNF168 rapid accumulation and its catalytic activity. Functionally, LLPS deficiency of RNF168 resulted in delayed recruitment of 53BP1 and BRCA1 and subsequent impairment in DSB repair. Taken together, our finding demonstrates the pivotal effect of LLPS in RNF168-mediated DSB repair.


Assuntos
Quebras de DNA de Cadeia Dupla , Reparo do DNA , Proteína 1 de Ligação à Proteína Supressora de Tumor p53 , Ubiquitina-Proteína Ligases , Ubiquitinação , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitina-Proteína Ligases/genética , Humanos , Proteína 1 de Ligação à Proteína Supressora de Tumor p53/metabolismo , Proteína 1 de Ligação à Proteína Supressora de Tumor p53/genética , Ubiquitina/metabolismo , Histonas/metabolismo , Histonas/genética , Poliubiquitina/metabolismo
2.
BMC Pediatr ; 24(1): 254, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38622552

RESUMO

BACKGROUND: SARS-CoV-2 infection is described as asymptomatic, mild, or moderate disease in most children. SARS-CoV-2 infection related death in children and adolescents is rare according to the current reports. COVID-19 cases increased significantly in China during the omicron surge, clinical data regarding pediatric critical patients infected with the omicron variant is limited. In this study, we aim to provide an overview of the clinical characteristics and outcomes of critically ill children admitted to a national children's medical center in Guangdong Province, China, during the outbreak of the omicron variant infection. METHODS: We conducted a retrospective study from November 25, 2022, to February 8, 2023, which included 63 critically ill children, under the age of 18, diagnosed with SARS-CoV-2 infection. The patients were referred from medical institutions of Guangdong province. The medical records of these patients were analyzed and summarized. RESULTS: The median age of patients was 2 years (Interquartile Range, IQR: 1.0-8.0), sex-ratio (male/female) was 1.52. 12 (19%) patients (age ≥ 3 years) were vaccinated. The median length of hospital stay was 14 days (IQR: 6.5-23) in 63 cases, and duration of fever was 5 days (IQR: 3-8.5), pediatric intensive care unit (PICU) stay was 8 days (IQR 4.0-14.0) in 57 cases. 30 (48%) cases had clear contact history with family members who were infected with SARS-CoV-2. Three children who tested positive for SARS-CoV-2 infection did not show any abnormalities on chest imaging examination. Out of the total patients, 33 (52%) had a bacterial co-infection, with Staphylococcus aureus being the most commonly detected bacterial pathogen. Our cohort exhibited respiratory and nervous system involvement as the primary features. Furthermore, fifty (79%) patients required mechanical ventilation, with a median duration of 7 days (IQR 3.75-13.0). Among these patients, 35 (56%) developed respiratory failure, 16 (25%) patients experienced a deteriorating progression of symptoms and ultimately succumbed to the illness, septic shock was the most common condition among these patients (15 cases), followed by multiple organ failure in 12 cases, and encephalopathy identified in 7 cases. CONCLUSION: We present a case series of critically ill children infected with the SARS-CoV-2 omicron variant. While there is evidence suggesting that Omicron may cause less severe symptoms, it is important to continue striving for measures that can minimize the pathogenic impact of SARS-CoV-2 infection in children.


Assuntos
COVID-19 , Adolescente , Humanos , Feminino , Criança , Masculino , Pré-Escolar , COVID-19/epidemiologia , SARS-CoV-2 , Estado Terminal , Estudos Retrospectivos , China/epidemiologia
3.
Cryobiology ; 112: 104557, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37451667

RESUMO

The objective of the study was to examine the effect of soy lecithin (SL) and cholesterol loaded cryclodestrin (CLC) on cryo-survival of sperm cryopreserved in the presence or absence of seminal plasma in Saanen dairy goats. Tris-based dilutions containing various concentrations of SL (0, 0.5%, 1.0% or 2.0%) and CLC (0, 2.0 g/L, 4.0 g/L or 6.0 g/L CLC) were used to cryopreserve Saanen dairy goat sperm. The quality of frozen-thawed sperm, including progressive motility, viability, acrosome and plasma membrane integrity, as well as fertility were detected. Results found that the optimal combination of the two cryoprotectants was 1.0% SL+4.0 g/L CLC, which significantly increased progressive motility, viability, acrosome and plasma membrane integrity of frozen thawed sperm. The impact of the two cryoprotectants in combination was not affected by the presence of seminal plasma. The conception rates obtained after artificial insemination using sperm cryopreserved with and without seminal plasma were 88.89% and 91.67% (P > 0.05), respectively. The respective values for average number of litter sizes were 1.55 ± 0.17 and 1.56 ± 0.21 (P > 0.05). Therefore, this study improved the cryopreservation efficiency of goat semen, enhanced the sperm cryosurvival, and layed a foundation for the wide application of frozen goat semen.


Assuntos
Ciclodextrinas , Preservação do Sêmen , Masculino , Animais , Ciclodextrinas/farmacologia , Lecitinas/farmacologia , Lecitinas/metabolismo , Glycine max/metabolismo , Criopreservação/métodos , Sementes , Espermatozoides , Crioprotetores/farmacologia , Crioprotetores/metabolismo , Preservação do Sêmen/veterinária , Preservação do Sêmen/métodos , Colesterol/farmacologia , Colesterol/metabolismo , Cabras/metabolismo , Motilidade dos Espermatozoides
4.
BMC Pulm Med ; 22(1): 246, 2022 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-35751045

RESUMO

BACKGROUND: Cyclin-dependent kinase inhibitor 2C (CDKN2C) was identified to participate in the occurrence and development of multiple cancers; however, its roles in small cell lung carcinoma (SCLC) remain unclear. METHODS: Differential expression analysis of CDKN2C between SCLC and non-SCLC were performed based on 937 samples from multiple centers. The prognosis effects of CDKN2C in patients with SCLC were detected using both Kaplan-Meier curves and log-rank tests. Using receiver-operating characteristic curves, whether CDKN2C expression made it feasible to distinguish SCLC was determined. The potential mechanisms of CDKN2C in SCLC were investigated by gene ontology terms and signaling pathways (Kyoto Encyclopedia of Genes and Genomes). Based on 10,080 samples, a pan-cancer analysis was also performed to determine the roles of CDKN2C in multiple cancers. RESULTS: For the first time, upregulated CDKN2C expression was detected in SCLC samples at both the mRNA and protein levels (p of Wilcoxon rank-sum test < 0.05; standardized mean difference = 2.86 [95% CI 2.20-3.52]). Transcription factor FOXA1 expression may positively regulate CDKN2C expression levels in SCLC. High CDKN2C expression levels were related to the poor prognosis of patients with SCLC (hazard ratio > 1, p < 0.05) and showed pronounced effects for distinguishing SCLC from non-SCLC (sensitivity, specificity, and area under the curve ≥ 0.95). CDKN2C expression may play a role in the development of SCLC by affecting the cell cycle. Furthermore, the first pan-cancer analysis revealed the differential expression of CDKN2C in 16 cancers (breast invasive carcinoma, etc.) and its independent prognostic significance in nine cancers (e.g., adrenocortical carcinoma). CDKN2C expression was related to the immune microenvironment, suggesting its potential usefulness as a prognostic marker in immunotherapy. CONCLUSIONS: This study identified upregulated CDKN2C expression and its clinical significance in SCLC and other multiple cancers, suggesting its potential usefulness as a biomarker in treating and differentiating cancers.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Carcinoma de Pequenas Células do Pulmão , Inibidor de Quinase Dependente de Ciclina p18/genética , Inibidor de Quinase Dependente de Ciclina p18/metabolismo , Humanos , Neoplasias Pulmonares/patologia , Prognóstico , Carcinoma de Pequenas Células do Pulmão/patologia , Microambiente Tumoral
5.
Chromosome Res ; 28(3-4): 247-258, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32895784

RESUMO

Mono-ubiquitination on H2B (H2Bub1) is an evolutionarily conserved histone post-translational modification implicated in various important physiological processes including DNA replication, transcription activation, and DNA damage repair. The Bre1/Rad6 ubiquitination machinery is currently considered to be the sole writer of H2Bub1, but the mechanistic basis by which it operates is unclear. Recently, the RING-type E3 ligase Bre1 was proposed to associate with the E2 enzyme Rad6 through a novel interaction between Bre1 RBD (Rad6 binding domain) and Rad6; and the RING domain of Bre1 that is responsible for the nucleosomal acidic patch binding also interacts with Rad6 to stimulate its catalytic activity. Recent discoveries have yielded evidence for the phenomenon of liquid-liquid phase separation in the context of H2Bub1, and its regulation by other histone post-translational modifications. This review summarizes current knowledge about Bre1/Rad6-mediated H2B ubiquitination, including the physiological functions and the molecular basis for writing and regulation of this central histone ubiquitin mark. Possible models for the Bre1/Rad6 machinery bound to nucleosomes bearing different modifications in the writing step are also disclosed.


Assuntos
Histonas/metabolismo , Enzimas de Conjugação de Ubiquitina/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitina/metabolismo , Animais , Humanos , Metilação , Nucleossomos/metabolismo , Relação Estrutura-Atividade , Elongação da Transcrição Genética , Ativação Transcricional , Enzimas de Conjugação de Ubiquitina/química , Ubiquitina-Proteína Ligases/química , Ubiquitinação
6.
BMC Pediatr ; 21(1): 297, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-34210262

RESUMO

BACKGROUND: Infantile malignant osteopetrosis (IMO) is a rare autosomal recessive disease characterized by a higher bone density in bone marrow caused by the dysfunction of bone resorption. Clinically, IMO can be diagnosed with medical examination, bone mineral density test and whole genome sequencing. CASE PRESENTATION: We present the case of a 4-month-old male infant with abnormal skull development, hypocalcemia and premature closure of the cranial sutures. Due to the hyper bone density showed by his radiographic examination, which are characteristic patterns of IMO, we speculated that he might be an IMO patient. In order to confirm this diagnosis, a high-precision whole exome sequencing of the infant and his parents was performed. The analysis of high-precision whole exome sequencing results lead to the identification of two novel heterozygous mutations c.504-1G > C (a splicing site mutation) and c.1371delC (p.G458Afs*70, a frameshift mutation) in gene TCIRG1 derived from his parents. Therefore, we propose that there is a close association between these two mutations and the onset of IMO. CONCLUSIONS: To date, these two novel mutations in gene TCIRG1 have not been reported in the reference gene database of Chinese population. These variants have likewise not been reported outside of China in the Genome Aggregation Database (gnomAD). Our case suggests that the use of whole exome sequencing to detect these two mutations will improve the identification and early diagnosis of IMO, and more specifically, the identification of homozygous individuals with TCIRG1 gene mutation. We propose that these mutations in gene TCIRG1 could be a novel therapeutic target for the IMO in the future.


Assuntos
Osteopetrose , ATPases Vacuolares Próton-Translocadoras , China , Homozigoto , Humanos , Lactente , Masculino , Mutação , Osteopetrose/diagnóstico por imagem , Osteopetrose/genética , ATPases Vacuolares Próton-Translocadoras/genética , ATPases Vacuolares Próton-Translocadoras/metabolismo
7.
Clin Exp Hypertens ; 43(8): 742-749, 2021 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-34338579

RESUMO

Objectives: This study was to investigate whether long-term amlodipine-based combination therapy attenuates seasonal variation of office blood pressure (BP) in hypertensive patients. Methods: The data of 206 patients recruited in the Nanchang site of CHIEF trial were retrospectively analyzed. All patients received an amlodipine-based therapy for three years after reaching target BP with a 12-week titration treatment. Among them, 106 patients received amlodipine plus amiloride/hydrochlorothiazide (AA group) and 100 received amlodipine plus telmisartan (AT group) therapies. These patients were followed up every three months . The difference between the highest and lowest values of outdoor temperature in each three months was calculated as the seasonal temperature difference (T-d) and seasonal BP difference was calculated in the similar way. BP control rates in each season were calculated. Results: In the three years, the highest SBP and DBP values occurred in winter and the lowest values in summer. As a result, the BP control rate in summer was the highest and that in winter was the lowest, especially for SBP. Although T-d levels were similar during three following-up years, the seasonal SBP/DBP differences in 2011 were significantly lower than 2009 (10.03 ± 5.74/6.96 ± 3.72 vs 14.36 ± 8.19/9.78 ± 5.21 mmHg, P < .05), suggesting seasonal variation in BP was obviously reduced. Meanwhile, similar change was observed in AA and AT groups. Conclusions: Besides lower BP effectively, long-term amlodipine-based combination therapy could alleviate the seasonal BP variation in high-risk hypertensive patients.


Assuntos
Hipertensão , Anlodipino/farmacologia , Anlodipino/uso terapêutico , Anti-Hipertensivos/farmacologia , Anti-Hipertensivos/uso terapêutico , Pressão Sanguínea , Quimioterapia Combinada , Humanos , Hipertensão/tratamento farmacológico , Estudos Retrospectivos , Estações do Ano , Resultado do Tratamento
8.
Clin Chem Lab Med ; 59(2): 249-266, 2020 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-32374277

RESUMO

Most hereditary diseases are incurable, but their deterioration could be delayed or stopped if diagnosed timely. It is thus imperative to explore the state-of-the-art and high-efficient diagnostic techniques for precise analysis of the symptoms or early diagnosis of pre-symptoms. Diagnostics based on clinical presentations, hard to distinguish different phenotypes of the same genotype, or different genotypes displaying similar phenotypes, are incapable of pre-warning the disease status. Molecular diagnosis is ahead of harmful phenotype exhibition. However, conventional gold-standard molecular classifications, such as karyotype analysis, Southern blotting (SB) and sequencing, suffer drawbacks like low automation, low throughput, prolonged duration, being labor intensive and high cost. Also, deficiency in flexibility and diversity is observed to accommodate the development of precise and individualized diagnostics. The aforementioned pitfalls make them unadaptable to the increasing clinical demand for detecting and interpreting numerous samples in a rapid, accurate, high-throughput and cost-effective manner. Nevertheless, capillary electrophoresis based on genetic information analysis, with advantages of automation, high speed, high throughput, high efficiency, high resolution, digitization, versatility, miniature and cost-efficiency, coupled with flexible-designed PCR strategies in sample preparation (PCR-CE), exhibit an excellent power in deciphering cryptic molecular information of superficial symptoms of genetic diseases, and can analyze in parallel a large number of samples in a single PCR-CE, thereby providing an alternative, accurate, customized and timely diagnostic tool for routine screening of clinical samples on a large scale. Thus, the present study focuses on CE-based nucleic acid analysis used for inherited disease diagnosis. Also, the limitations and challenges of this PCR-CE for diagnosing hereditary diseases are discussed.


Assuntos
Biomarcadores/análise , Eletroforese Capilar/métodos , Doenças Genéticas Inatas/diagnóstico , Ácidos Nucleicos/análise , Southern Blotting , Genótipo , Ensaios de Triagem em Larga Escala , Humanos , Reação em Cadeia da Polimerase , Espectrometria de Fluorescência
9.
Hum Mutat ; 40(4): 392-403, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30609140

RESUMO

Primary familial brain calcification (PFBC) is a rare neurodegenerative disorder with four causative genes (SLC20A2, PDGFRB, PDGFB, and XPR1) that have been identified. Here, we aim to describe the mutational spectrum of four causative genes in a series of 226 unrelated Chinese PFBC patients. Mutations in four causative genes were detected in 16.8% (38/226) of PFBC patients. SLC20A2 mutations accounted for 14.2% (32/226) of all patients. Mutations in the other three genes were relatively rare, accounting for 0.9% (2/226) of all patients, respectively. Clinically, 44.8% of genetically confirmed patients (probands and relatives) were considered symptomatic. The most frequent symptoms were chronic headache, followed by movement disorders and vertigo. Moreover, the total calcification score was significantly higher in the symptomatic group compared to the asymptomatic group. Functionally, we observed impaired phosphate transport induced by seven novel missense mutations in SLC20A2 and two novel mutations in XPR1. The mutation p.D164Y in XPR1 might result in low protein expression through an enhanced proteasome pathway. In conclusion, our study further confirms that mutations in SLC20A2 are the major cause of PFBC and provides additional evidence for the crucial roles of phosphate transport impairment in the pathogenies of PFBC.


Assuntos
Encefalopatias/genética , Calcinose/genética , Predisposição Genética para Doença , Mutação , Doenças Neurodegenerativas/genética , Adulto , Idoso , Alelos , Transporte Biológico , Biomarcadores , Encefalopatias/diagnóstico , Encefalopatias/metabolismo , Calcinose/diagnóstico , Calcinose/metabolismo , Linhagem Celular Tumoral , China , Feminino , Genes sis , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Doenças Neurodegenerativas/diagnóstico , Doenças Neurodegenerativas/metabolismo , Neuroimagem , Fenótipo , Receptor beta de Fator de Crescimento Derivado de Plaquetas/genética , Receptores Acoplados a Proteínas G/genética , Receptores Virais/genética , Proteínas Cotransportadoras de Sódio-Fosfato Tipo III/genética , Tomografia Computadorizada por Raios X , Receptor do Retrovírus Politrópico e Xenotrópico
10.
Mikrochim Acta ; 186(5): 296, 2019 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-31016400

RESUMO

An innovative approach is presented for portable and sensitive detection of pathogenic bacteria. A novel synthetic hybrid nanocomposite encapsulating platinum nanoparticles, as a highly efficient catalyst, catalyzes the hydrolysis of the ammonia-borane complex to generate hydrogen gas. The nanocomposites are used as a label for immunoassays. A portable hand-held hydrogen detector combined with nanocomposite-induced signal conversion was applied for point-of-care testing of pathogenic bacteria. A hand-held hydrogen detector was used as the transducer. Escherichia coli O157:H7 (E. coli O157: H7), as detection target, formed a sandwich structure with magnetic beads and hybrid nanocomposites. Magnetic beads were used for separation of the sandwich structure, and hybrid nanocomposites as catalysts to catalyze the generation of hydrogen from ammonia-borane. The generated hydrogen was detected by a hydrogen detector using an electrochemical method. E. coli O157:H7 has a detection limit of 10 CFU·mL-1. The immunosensor made the hand-held hydrogen detector a point-of-care meter to be used outdoors for the detection and quantification of targets beyond hydrogen. Graphical abstract Schematic presentation of one-pot synthetic peptide-Cu3(PO4)2 hybrid nanocomposites embedded PtNPs (PPNs), encapsulating many Pt particles. The PPNs acts as an ideal immunoprobe for hand-held H2 detector signal readouts, by transforming pathogenic bacteria recognition events into H2 signals.

11.
Microvasc Res ; 115: 58-67, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28870649

RESUMO

The endotoxin lipopolysaccharide (LPS)-induced pulmonary endothelial barrier disruption is a key pathogenesis of acute lung injury (ALI) and acute respiratory distress syndrome (ARDS). However, the molecular mechanisms underlying LPS-impaired permeability of pulmonary microvascular endothelial cells (PMVECs) are not fully understood. Gap junctions, particularly Connexin40 (Cx40), are necessary for the maintenance of normal vascular function. In this study, we for the first time investigated the role of Cx40 in LPS-impaired permeability of PMVECs and provided potential therapeutic approaches based on mechanistic findings of Cx40 regulation by LPS stimuli. Rat PMVECs were isolated, cultured and identified with cell morphology, specific markers, ultrastructural characteristics and functional tests. Western blot analysis demonstrated that Cx40 is the major connexin highly expressed in PMVECs. Furthermore, by inhibiting Cx40 in a time-dependent manner, LPS impaired gap junction function and induced permeability injury of PMVECs. The key role of Cx40 decline in mediating detrimental effects of LPS was further confirmed in rescue experiments through Cx40 overexpression. Mechanistically, LPS stress on PMVECs inhibited the protein kinase C (PKC) pathway, which may synergize with the inflammatory nuclear factor kappaB (NFκB) signaling activation in suppressing Cx40 expression level and phosphorylation. Moreover, through pharmacological PKC activation or NFκB inhibition, Cx40 activity in PMVECs could be restored, leading to maintained barrier function under LPS stress. Our findings uncover a previously unrecognized role of Cx40 and its regulatory mechanisms in impaired endothelial integrity under endotoxin and inflammation, shedding light on intervention approaches to improve pulmonary endothelial barrier function in ALI and ARDS.


Assuntos
Permeabilidade Capilar/efeitos dos fármacos , Conexinas/metabolismo , Células Endoteliais/efeitos dos fármacos , Lipopolissacarídeos/toxicidade , Pulmão/irrigação sanguínea , Microvasos/efeitos dos fármacos , Animais , Células Cultivadas , Conexinas/genética , Relação Dose-Resposta a Droga , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Junções Comunicantes/efeitos dos fármacos , Junções Comunicantes/metabolismo , Junções Comunicantes/patologia , Microvasos/metabolismo , Microvasos/patologia , NF-kappa B/metabolismo , Fosforilação , Proteína Quinase C/metabolismo , Ratos , Transdução de Sinais/efeitos dos fármacos , Fatores de Tempo , Proteína alfa-5 de Junções Comunicantes
12.
Compr Rev Food Sci Food Saf ; 16(6): 1281-1295, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33371590

RESUMO

Food safety and food production are closely related to the health of consumers. Food-related accidents often cause tremendous losses of personnel and property. Thus, rapid detection and analysis of ingredients in food, tracing food sources, studying the optimal conditions for food production, and more are vital for preventing incidents related to safety. Conventional analysis based on proteomics, microbial cultures, and morphology, as well as biochemical tests based on metabonomics, are considered gold standards and used frequently, but they are labor-intensive, time-consuming, tedious, error-prone, and incapable of meeting the demand for rapid and precise detection at a large scale. Alternative detection methods that utilize capillary electrophoresis have the advantages of high efficiency, high throughput, high speed, and automation; these methods are coupled with various nucleic acid detection strategies to overcome the drawbacks of traditional identification methods, and to prevent false results. Therefore, this review focuses on the application of capillary electrophoresis based on nucleic acid detection in food analysis and provides an introduction to the limitations, advantages, and future developments of this approach.

13.
Exp Cell Res ; 330(2): 267-276, 2015 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-25220423

RESUMO

Radiotherapy is an essential component of the standard therapy for newly diagnosed glioblastoma. To increase the radiosensitivity of glioma cells is a feasible solution to improve the therapeutic effects. It has been suggested that inhibition of signal transducer and activator of transcription 3 (STAT3) can radiosensitize glioma cells, probably via the activation of mitochondrial apoptotic pathway. In this study, human malignant glioma cells, U251 and A172, were treated with an STAT3 inhibitor, WP1066, or a short hairpin RNA plasmid targeting STAT3 to suppress the activation of STAT3 signaling. The radiosensitizing effects of STAT3 inhibition were confirmed in glioma cells. Intriguingly, combination of ionizing radiation exposure and STAT3 inhibition triggered a pronounced increase of autophagy flux. To explore the role of autophagy, glioma cells were treated with 3-methyladenine or siRNA for autophagy-related gene 5, and it was demonstrated that inhibition of autophagy further strengthened the radiosensitizing effects of STAT3 inhibition. Accordingly, more apoptotic cells were induced by the dual inhibition of autophagy and STAT3 signaling. In conclusion, our data revealed a protective role of autophagy in the radiosensitizing effects of STAT3 inhibition, and inhibition of both autophagy and STAT3 might be a potential therapeutic strategy to increase the radiosensitivity of glioma cells.


Assuntos
Autofagia/efeitos da radiação , Neoplasias Encefálicas/radioterapia , Glioma/radioterapia , Tolerância a Radiação , Fator de Transcrição STAT3/antagonistas & inibidores , Adenina/análogos & derivados , Adenina/farmacologia , Apoptose/fisiologia , Apoptose/efeitos da radiação , Autofagia/efeitos dos fármacos , Proteína 5 Relacionada à Autofagia , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Glioma/patologia , Humanos , Proteínas Associadas aos Microtúbulos/genética , Mitocôndrias/metabolismo , Piridinas/farmacologia , Interferência de RNA , RNA Interferente Pequeno , Radiação Ionizante , Fator de Transcrição STAT3/genética , Tirfostinas/farmacologia
14.
Tumour Biol ; 36(6): 4339-48, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25596087

RESUMO

The aim of this study was to decide whether nicotinamide (NA) could induce apoptosis of F9 mouse teratocarcinoma stem cells (MF9) by downregulation of special AT-rich sequence binding protein 1 (SATB1) expression. We used different concentrations of NA (0, 1.5, 2, and 2.5 mmol/L) to treat MF9 cells and analyze SATB1 expression by RT-qPCR and Western blotting; in addition, the cell proliferation was detected in a microplate reader with Cell Counting Kit-8 (CCK-8), and the cell cycle and apoptosis were analyzed using flow cytometry. We found that the expression of SATB1 was decreased significantly in NA-treated groups than in the control group, and its expression level was inversely related to the NA concentration. In addition, CCK-8 analysis showed that NA significantly inhibited the proliferation of MF9 cells, and flow cytometry showed that NA blocked MF9 cells to G1 phase and significantly promoted apoptosis in any treated groups. To confirm the results, we constructed small interference RNA (siRNA) targeting at mouse SATB1 and transferred into MF9 cells. The results indicated that the expression of SATB1 in both mRNA and protein levels was significantly decreased after cells transferred with siRNA sequence for 48 h, the proliferation of MF9 cells was significantly inhibited, and most of MF9 cells were blocked at G1 phase, and the apoptosis rate was increased obviously. The results showed that NA could inhibit the proliferation and induce apoptosis of MF9 cells. These findings might be used as an efficient candidate for teratocarcinoma therapy.


Assuntos
Apoptose/efeitos dos fármacos , Células-Tronco de Carcinoma Embrionário/metabolismo , Proteínas de Ligação à Região de Interação com a Matriz/biossíntese , Niacinamida/administração & dosagem , Animais , Apoptose/genética , Proliferação de Células/efeitos dos fármacos , Células-Tronco de Carcinoma Embrionário/patologia , Regulação Neoplásica da Expressão Gênica , Humanos , Proteínas de Ligação à Região de Interação com a Matriz/genética , Camundongos , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , RNA Mensageiro/biossíntese
15.
AJR Am J Roentgenol ; 204(2): 330-4, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25615755

RESUMO

OBJECTIVE. The purpose of this study was to determine an optimal multiparametric MRI protocol for characterizing tumors of low versus high grade and differentiating tumors as T1 versus T2 for preoperative staging of bladder urothelial carcinoma. SUBJECTS AND METHODS. Thirty-nine patients underwent MRI within 1 week before surgery. Three image sets-T2-weighted plus diffusion-weighted MRI (DWI), T2-weighted plus dynamic contrast-enhanced MRI (DCE-MRI), and T2-weighted plus DCEMRI plus DWI-were independently interpreted by two readers at 2-week intervals. ROC curves were plotted for both readers to compare the diagnostic efficacy of the three sets for detrusor muscle invasion for each reader, and the areas under the ROC curve were compared by use of the Bonferroni test. The apparent diffusion coefficient (ADC) values were correlated with histopathologic grade. RESULTS. A total of 49 category T1 and T2 lesions were analyzed. The average ADC of 11 low-grade tumors (1.141 ± 0.164 × 10(-3) mm(2)/s) was significantly (p < 0.05) higher than that of 20 high-grade malignant tumors (0.766 ± 0.091 × 10(-3) mm(2)/s). Neither reader considered T1 tumors as probably having muscle invasion (category T2) in the T2-weighted plus DWI image sets or the T2-weighted plus DWI plus DCE-MRI image sets. Using the T2-weighted plus DCE-MRI sets, the two readers overstaged 13 and 15 of 36 tumors by misdiagnosing category T1 as T2. With the cutoff ADC value of 0.899 × 10-3 mm(2)/s, the sensitivity and specificity for differentiating high- and low-grade bladder urothelial carcinoma were 100% and 95%. CONCLUSION. Multiparametric MRI with T2-weighted plus DWI plus DCE technique is the optimal protocol for preoperative staging of organ-confined bladder urothelial carcinoma. The ADC of low-grade tumors is significantly higher than that of high-grade tumors with 100% sensitivity and 95% specificity at a cutoff ADC value of 0.899 mm(2)/s.


Assuntos
Carcinoma de Células de Transição/patologia , Imageamento por Ressonância Magnética/métodos , Neoplasias da Bexiga Urinária/patologia , Adulto , Idoso , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , Sensibilidade e Especificidade
16.
Clin Lab ; 61(11): 1727-35, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26731999

RESUMO

BACKGROUND: To investigate the distribution of stenosis of intracranial and extracranial arteries of Han population patients suffering from cerebral infarction in the city of Quanzhou in Fujian and to determine the correlation of apolipoprotein A1 and apolipoprotein B with intracranial and extracranial atherosclerosis stenosis. METHODS: For this study, we enrolled patients with cerebral infarction between December 2009 and October 2012 at the Neurology Department of The Second Affiliated Hospital of Fujian Medical University. All patients were examined by computed tomography angiography (CTA). Past medical history, demographic data, and biochemical markers were collected. Multiple logistic regression analysis was used to study the association between apo A1, apo B, and cerebral atherosclerosis stenosis. RESULTS: A total of 412 patients were included in this study. 137 cases (33.3%) were classified as the intracranial atherosclerosis stenosis (ICAS) group, 74 cases (18.0%) as the combined intracranial and extracranial atherosclerosis stenosis (COAS) group, 44 cases (0.7%) as the extracranial atherosclerosis stenosis (ECAS) group, and 157 cases (38.1%) as the non-cerebral atherosclerosis stenosis (NCAS) group. Middle cerebral arteries (43.8%) were the most common lesions of intracranial arterial atherosclerosis stenosis. Extracranial carotid stenosis (30.7%) were more likely to be stenoses in the extracranial internal carotid arteries. Compared with the NCAS group, apo B was significantly higher (p < 0.001), apo A1 was significantly lower in the ICAS group and COAS group (p = 0.02 and p = 0.030). Compared with the mild atherosclerosis stenosis group, apo B was higher in the severe extracranial atherosclerosis stenosis group (p = 0.03), apo A1 was lower in the severe intracranial atherosclerosis stenosis group (p < 0.001). The multiple logistic regression analyses showed that when apo A1 > 1.28 g/L, it was an independent protective factor of intracranial stenosis (OR, 0.39), apo B was an independent risk factor of the cerebral atherosclerosis stenosis group, and when apo B > 1.16, it is significantly associated with the cerebral atherosclerosis stenosis group (ICAS: OR, 6.41) (ECAS: OR, 5.15). CONCLUSIONS: 1. The occurrence of atherosclerosis stenosis in intracranial arteries is more frequent than that in extracranial arteries in population with cerebral infarction; 2. Apo B is an independent risk factor of intracranial and extracranial arterial stenosis, apo A1 is associated with the degree of intracranial stenosis and an independent protector of intracranial stenosis.


Assuntos
Apolipoproteína A-I/sangue , Apolipoproteínas B/sangue , Artérias/patologia , Aterosclerose/sangue , Artérias Cerebrais/patologia , Acidente Vascular Cerebral/sangue , Idoso , Estudos de Casos e Controles , Humanos , Pessoa de Meia-Idade
17.
Zhejiang Da Xue Xue Bao Yi Xue Ban ; 44(2): 162-6, 2015 03.
Artigo em Chinês | MEDLINE | ID: mdl-26038134

RESUMO

OBJECTIVE: To investigate the effect of irradiated human lung fibroblasts (HLFs) on the canonical Wnt/ß-catenin signaling pathway in human umbilical cord mesenchymal stem cells (HUMSCs). METHODS: HUMSCs were cultured alone (single group) or co-cultured with HLFs exposed to 5Gy X-rays (co-culture group). The protein levels of GSK-3ß, p-GSK-3ß, FRAT1 and ß-catenin in HUMSCs were examined by Western blotting 3 days after culture or co-culture. WISP-1 protein levels in conditioned medium were examined by ELISA. RESULTS: The levels of p-GSK3ß/GSK3ß (0.15 ± 0.05), FRAT1 (0.48 ± 0.07) and ß-catenin (0.50 ± 0.07) in co-cultured HUMSCs significantly decreased compared to those in single group (0.55 ± 0.05, 1.16 ± 0.13 and 2.39 ± 0.15, all P<0.05). The supernatant level of WISP-1 in co-culture group was significantly decreased [(602.23 ± 161.47) ng/mL], compared to the single group [(977.77 ± 110.56) ng/mL, P<0.05]. CONCLUSION: Irradiated HLFs attenuate the activation of canonical Wnt/ß-catenin signaling pathway in HUMSCs in vitro.


Assuntos
Fibroblastos/citologia , Células-Tronco Mesenquimais/metabolismo , Via de Sinalização Wnt , Proteínas Adaptadoras de Transdução de Sinal , Proteínas de Sinalização Intercelular CCN/metabolismo , Células Cultivadas , Técnicas de Cocultura , Fibroblastos/efeitos da radiação , Raios gama , Quinase 3 da Glicogênio Sintase/metabolismo , Glicogênio Sintase Quinase 3 beta , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Cordão Umbilical/citologia , Raios X , beta Catenina/metabolismo
18.
Mol Reprod Dev ; 81(1): 87-97, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24347442

RESUMO

The goal of this study was to improve the development of bovine somatic-cell nuclear transfer (SCNT) embryos by optimizing the combination of DNA methyltransferases inhibitor S-adenosylhomocysteine (SAH) and histone deacetylase inhibitor Scriptaid (SPD). A. 4 × 4-factor design of different drug combinations (0, 0.75, 1.0, and 1.5 mM SAH and 0, 5, 250, and 500 nM SPD) was used to identify an optimal combination of 0.75 mM SAH and 250 nM SPD that improved the developmental competence of bovine SCNT embryos. Further experiments using this combination revealed that methylation levels of CpG islands near exon 1 of the pluripotent gene SOX2; the epigenetic-related gene HDAC3 and DNMT3a; imprinted genes XIST and PEG3; as well as apoptosis-related genes BCL2 and BAX were returned to levels similar to those of in vitro fertilized (IVF) embryo after treatment, which also normalized transcript levels for these genes. This combination also returned global DNA methylation to a normal level, correcting H4K12ac levels while enhancing H3K9ac levels. Thus, the combined application of 0.75 mM SAH and 250 nM SPD can significantly improve the reprogramming of bovine SCNT embryos by stabilizing how embryos utilize their genomes.


Assuntos
Cruzamento/métodos , Bovinos/embriologia , Embrião de Mamíferos/efeitos dos fármacos , Epigênese Genética/efeitos dos fármacos , Hidroxilaminas/farmacologia , Quinolinas/farmacologia , S-Adenosil-Homocisteína/farmacologia , Animais , Sequência de Bases , Ilhas de CpG/genética , Metilação de DNA/efeitos dos fármacos , Metilases de Modificação do DNA/antagonistas & inibidores , Primers do DNA/genética , Combinação de Medicamentos , Embrião de Mamíferos/embriologia , Imunofluorescência , Técnicas Histológicas , Inibidores de Histona Desacetilases/farmacologia , Histona Desacetilases/genética , Dados de Sequência Molecular , Técnicas de Transferência Nuclear , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Transcrição SOXB1/genética , Análise de Sequência de DNA
19.
Mol Reprod Dev ; 81(3): 257-69, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24347534

RESUMO

This study aimed to investigate the effects of 3-hydroxyflavone, a natural antioxidant pigment enriched in vegetables, on the developmental cellular and molecular characteristics of bovine somatic-cell nuclear transfer (SCNT) embryos. There were no significant differences in the cleavage rate at 48 hr of culture or in the inner cell mass (ICM)-to-trophectoderm (TE) ratio between 3-hydroxyflavone addition and untreated (control) groups (P > 0.05). 3-hydroxyflavone (20 µM) did, however, increase the cleavage rate at 24 hr of culture and the blastocyst-formation rate on Days 6 and 7 (P < 0.05); decrease the levels of intracellular reactive oxygen species in two-, four-, and eight-cell stage embryos (P < 0.05); increase H3K9ac levels in two- and four-cell stages (P < 0.05); increase the total cell number; and decrease the apoptosis index in Day-7 blastocysts. Furthermore, the addition of 3-hydroxyflavone resulted in lower expression of the stress-related gene HSP70.1 and pro-apoptotic gene BAX, as well as higher expression of the anti-apoptotic gene BCL-xL and pluripotency-related genes OCT4 and SOX2 in Day-7 blastocysts produced by SCNT (P < 0.05). The addition of 3-hydroxyflavone during in vitro culture thus exerted beneficial effects on preimplantation development of bovine SCNT embryos both at the cellular and molecular levels.


Assuntos
Antioxidantes/farmacologia , Blastocisto/efeitos dos fármacos , Flavonoides/farmacologia , Técnicas de Transferência Nuclear , Animais , Apoptose/efeitos dos fármacos , Blastocisto/química , Blastocisto/citologia , Blastocisto/metabolismo , Bovinos , Feminino , Masculino , Espécies Reativas de Oxigênio/análise
20.
Environ Sci Technol ; 48(17): 10398-405, 2014 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-25102367

RESUMO

This study epigenetically examined the effect of fluoride on early embryos of Kunming mice administered with 0, 20 (low), 60 (medium), and 120 mg/L (high) sodium fluoride (NaF). The results showed that NaF repressed oocyte maturation, fertilization and blastocyst formation in all NaF-treated groups. Meanwhile, TUNEL assay showed that embryo apoptosis was induced dramatically in blastocyst stage at either low or medium doses, and in 8-cell stage at high dose, compared to the control, suggesting a dose-dependent effect. Furthermore, the immunostaining displayed global increases of DNA methylation, H3K9m2 and H3K4m2 with increasing dose, which were consistent with gene expression results, exhibiting general increases of DNMT1, DNMT3a, G9a, LSD1, and MLL1 and a reduction of JHDM2a in transcription and protein levels. More closely, the differential methylation domain in parentally imprinted gene H19 showed low methylation, while materanlly imprinted gene IGF2 showed high methylaiton in NaF-treated groups compared to the control group, which corresponded with high expression of H19 and low expression of IGF2 confirmed by qPCR. Collectively, we demonstrated that fluoride epigenetically impaired mouse oocyte maturation and embryonic development, supplying a better knowledge of fluoride in toxicology and a deeper evaluation of its potential influence in physiological and clinical implications.


Assuntos
Apoptose/genética , Metilação de DNA/genética , Embrião de Mamíferos/metabolismo , Processamento de Proteína Pós-Traducional/genética , Fluoreto de Sódio/farmacologia , Animais , Apoptose/efeitos dos fármacos , Sequência de Bases , Blastômeros/citologia , Blastômeros/efeitos dos fármacos , Blastômeros/metabolismo , Ilhas de CpG/genética , Metilação de DNA/efeitos dos fármacos , Embrião de Mamíferos/citologia , Embrião de Mamíferos/efeitos dos fármacos , Desenvolvimento Embrionário/efeitos dos fármacos , Desenvolvimento Embrionário/genética , Feminino , Fertilização/efeitos dos fármacos , Fertilização/genética , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Histonas/metabolismo , Humanos , Marcação In Situ das Extremidades Cortadas , Técnicas de Maturação in Vitro de Oócitos , Fator de Crescimento Insulin-Like II/genética , Masculino , Camundongos , Dados de Sequência Molecular , Gravidez , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , RNA Longo não Codificante , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
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