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1.
Nat Microbiol ; 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38740932

RESUMO

Phthiocerol dimycocerosate (PDIM) is an essential virulence lipid of Mycobacterium tuberculosis. In vitro culturing rapidly selects for spontaneous PDIM-negative mutants that have attenuated virulence and increased cell wall permeability, thus impacting the relevance of experimental findings. PDIM loss can also reduce the efficacy of the BCG Pasteur vaccine. Here we show that vancomycin susceptibility can rapidly screen for M. tuberculosis PDIM production. We find that metabolic deficiency of methylmalonyl-CoA impedes the growth of PDIM-producing bacilli, selecting for PDIM-negative variants. Supplementation with odd-chain fatty acids, cholesterol or vitamin B12 restores PDIM-positive bacterial growth. Specifically, we show that propionate supplementation enhances PDIM-producing bacterial growth and selects against PDIM-negative mutants, analogous to in vivo conditions. Our study provides a simple approach to screen for and maintain PDIM production, and reveals how discrepancies between the host and in vitro nutrient environments can attenuate bacterial pathogenicity.

2.
J Environ Manage ; 358: 120836, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38593741

RESUMO

Supercritical water gasification technology provides a favorable technology to achieve pollution elimination and resource utilization of phenolic wastewater. In this study, the reaction mechanism of phenolic wastewater supercritical water gasification was investigated using a combination of experimental and computational methods. Five reaction channels were identified to elucidate the underlying pathway of phenol decomposition. Importantly, the rate-determining step was found to be the dearomatization reaction. By integrating computational and experimental analyses, it was found that phenol decomposition via the path with the lowest energy barrier generates cyclopentadiene, featuring a dearomatization barrier of 70.97 kcal/mol. Additionally, supercritical water plays a catalytic role in the dearomatization process by facilitating proton transfer. Based on the obtained reaction pathway, alkali salts (Na2CO3 and K2CO3) are employed as a catalyst to diminish the energy barrier of the rate-determining step to 40.00 kcal/mol and 37.14 kcal/mol. Alkali salts catalysis significantly improved carbon conversion and pollutant removal from phenolic wastewater, increasing CGE from 58.44% to 93.55% and COD removal efficiency from 94.11% to 99.79%. Overall, this study provides a comprehensive understanding of the decomposition mechanism of phenolic wastewater in supercritical water.


Assuntos
Águas Residuárias , Águas Residuárias/química , Catálise , Fenóis/química , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/química , Água/química
3.
bioRxiv ; 2023 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-37905120

RESUMO

Phthiocerol dimycocerosate (PDIM) is an essential virulence lipid of Mycobacterium tuberculosis. In vitro culturing rapidly selects for spontaneous mutations that cause PDIM loss leading to virulence attenuation and increased cell wall permeability. We discovered that PDIM loss is due to a metabolic deficiency of methylmalonyl-CoA that impedes the growth of PDIM-producing bacilli. This can be remedied by supplementation with odd-chain fatty acids, cholesterol, or vitamin B12. We developed a much-needed facile and scalable routine assay for PDIM production and show that propionate supplementation enhances the growth of PDIM-producing bacilli and selects against PDIM-negative mutants, analogous to in vivo conditions. Our results solve a major issue in tuberculosis research and exemplify how discrepancies between the host and in vitro nutrient environments can attenuate bacterial pathogenicity.

4.
bioRxiv ; 2023 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-37292828

RESUMO

MicroRNAs (miRNAs) have been demonstrated to modulate life span in the invertebrates C. elegans and Drosophila by targeting conserved pathways of aging, such as insulin/IGF-1 signaling (IIS). However, a role for miRNAs in modulating human longevity has not been fully explored. Here we investigated novel roles of miRNAs as a major epigenetic component of exceptional longevity in humans. By profiling the miRNAs in B-cells from Ashkenazi Jewish centenarians and 70-year-old controls without a longevity history, we found that the majority of differentially expressed miRNAs were upregulated in centenarians and predicted to modulate the IIS pathway. Notably, decreased IIS activity was found in B cells from centenarians who harbored these upregulated miRNAs. miR-142-3p, the top upregulated miRNA, was verified to dampen the IIS pathway by targeting multiple genes including GNB2, AKT1S1, RHEB and FURIN . Overexpression of miR-142-3p improved the stress resistance under genotoxicity and induced the impairment of cell cycle progression in IMR90 cells. Furthermore, mice injected with a miR-142-3p mimic showed reduced IIS signaling and improved longevity-associated phenotypes including enhanced stress resistance, improved diet/aging-induced glucose intolerance, and longevity-associated change of metabolic profile. These data suggest that miR-142-3p is involved in human longevity through regulating IIS-mediated pro-longevity effects. This study provides strong support for the use of miR-142-3p as a novel therapeutic to promote longevity or prevent aging/aging-related diseases in human.

5.
Infect Drug Resist ; 16: 4013-4023, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37377730

RESUMO

Purpose: To investigate the epidemiology, etiology, and clinical characteristics of patients with pyogenic liver abscesses (PLA) and provide guidance for clinical treatments. Patients and Methods: A retrospective study was performed on a cohort of 402 hospitalized patients diagnosed with PLAs at the Affiliated Hospital of Chengde Medical College between January 2016 and December 2021. Patient demographics, drug sensitivity profiles, and microbiological culture results of drainage and blood samples were thoroughly analyzed to identify significant patterns or trends. Furthermore, clinical characteristics and treatments for patients with PLA were comprehensively assessed. Results: Patients aged 50-69 years had the highest incidence of PLA, accounting for 59.9% of all cases, and 91.5% of them had a fever. Bacterial culture analysis of the 200 patients revealed that Klebsiella pneumoniae (K. pneumoniae) was the most predominant pathogen, detected in 70.5% of cases, exhibiting an upward trend. Escherichia coli (E. coli) was the second most frequently detected pathogen, identified in 14.5% of cases, showing a downward trend. Coexisting diabetes mellitus (DM) was found to be the most common comorbidity for PLA, occurring in most patients with the condition. Patients with a history of abdominal surgery and malignancy had an increased risk for PLA, while those with gallstones had a decreased risk. Drainage combined with antibiotic therapy was identified as the primary treatment of PLA. In addition, multivariate analysis demonstrated that coexisting DM and the presence of gas in the abscess cavity were independent risk factors for septic shock in patients with PLA. Conclusion: This study reveals a shift in the proportions of pathogens and risk factors in patients with PLA, underscoring the necessity for improved diagnostic and therapeutic strategies.

6.
Biotechnol Genet Eng Rev ; : 1-14, 2023 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-37066882

RESUMO

Propofol is an ultra-fast-acting intravenous anesthetic, which is rapidly metabolized primarily into inactive compounds in the live and then excreted in the urine. The purpose of this study is to explore the risk signals of propofol based on the US FDA Adverse Event Reporting System database. The risk signals of propofol-related adverse reactions in adverse event (AE) reports from 2004 to 2021 in the US FAERS were mined using ratio-report method (ROR) and the ratio-report ratio method (PRR) methods. We screened out 1651 pairs AE reports using propofol as primary suspect (PS) drugs. ROR, PRR, BCPNN and MGPS methods were used to calculate respectively, there are 363 positive preferred terms (PT) signals with 9549 cases. Among them, the top 3 adverse reactions associated with using propofol from the FAERS database were anaphylactic shock, hypotension and propofol infusion syndrome. The top 3 systems of the body associated with adverse reaction of propofol from the FAERS database were General disorders, Cardiac disorders and administration site conditions and Respiratory, thoracic and mediastinal disorders. The top 4 indication of using propofol from the FAERS database, including anaesthesia, induction of anaesthesia, sedation, general anaesthesia. There are many adverse reactions that are not included in the drug insert of propofol and involve a wide range of organs and/or systems. Caution should be exercised in the clinical use of propofol.

7.
Medicine (Baltimore) ; 101(48): e32123, 2022 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-36482622

RESUMO

BACKGROUND: Gastrointestinal bleeding caused by a ruptured pancreatic pseudoaneurysm is rare, and a pseudoaneurysm of the posterior inferior pancreaticoduodenal artery is especially rare. A 68-year-old man was hospitalized after presenting intermittent black stools and dyspnea accompanied by severe anemia. Angiographic examination revealed that Pseudoaneurysm of the posterior inferior pancreaticoduodenal artery. METHODS: Angiography was performed and revealed a pseudoaneurysm of the posterior inferior pancreaticoduodenal artery. Subsequently, a blood transfusion and endovascular embolization were performed. RESULTS: The patient's gastrointestinal bleeding stopped, and the hemoglobin level remained stable. During 1 year of follow-up, the patient remained in a generally good condition. CONCLUSION: posterior inferior pancreaticoduodenal artery pseudoaneurysmIt is rare and difficult to diagnose, gastrointestinal bleeding is a serious complication, vascular interventional embolization is effective.


Assuntos
Artérias , Hemorragia Gastrointestinal , Humanos , Idoso , Hemorragia Gastrointestinal/etiologia , Hemorragia Gastrointestinal/terapia
8.
Rev Esc Enferm USP ; 55: e03729, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34190882

RESUMO

OBJECTIVE: To investigate the effect of the FOCUS-PDCA procedure on the self-care ability of patients undergoing colostomy for rectal cancer. METHOD: A nonrandomized controlled trial of 160 patients with rectal cancer undergoing colostomy. The control group received routine nursing intervention, and the observation group received the FOCUS-PDCA procedure. The self-care ability of the two groups was investigated 1 week and 1 month after surgery, and a comparative analysis was made between the groups. RESULTS: One week after surgery, the self-care ability of rectal cancer patients with colostomy increased from 39.09 points before implementation of the FOCUS-PDCA procedure to 60.15 points after implementation; an increase of 21.06%. One month after surgery, the self-care ability increased from 61.50 points to 83.13 points after implementation of the FOCUS-PDCA procedure; an increase of 21.63%. CONCLUSION: Application of the FOCUS-PDCA procedure improved the self-care ability of rectal cancer patients undergoing colostomy, improved their physical and mental health, reduced colostomy complications, and improved their quality of life. The results suggest that it is worth applying FOCUS-PDCA more widely.


Assuntos
Colostomia , Neoplasias Retais , Humanos , Complicações Pós-Operatórias , Qualidade de Vida , Neoplasias Retais/cirurgia , Autocuidado
9.
Rev. Esc. Enferm. USP ; 55: e03729, 2021. tab, graf
Artigo em Inglês | LILACS, BDENF - Enfermagem | ID: biblio-1279643

RESUMO

ABSTRACT Objective: To investigate the effect of the FOCUS-PDCA procedure on the self-care ability of patients undergoing colostomy for rectal cancer. Method: A nonrandomized controlled trial of 160 patients with rectal cancer undergoing colostomy. The control group received routine nursing intervention, and the observation group received the FOCUS-PDCA procedure. The self-care ability of the two groups was investigated 1 week and 1 month after surgery, and a comparative analysis was made between the groups. Results: One week after surgery, the self-care ability of rectal cancer patients with colostomy increased from 39.09 points before implementation of the FOCUS-PDCA procedure to 60.15 points after implementation; an increase of 21.06%. One month after surgery, the self-care ability increased from 61.50 points to 83.13 points after implementation of the FOCUS-PDCA procedure; an increase of 21.63%. Conclusion: Application of the FOCUS-PDCA procedure improved the self-care ability of rectal cancer patients undergoing colostomy, improved their physical and mental health, reduced colostomy complications, and improved their quality of life. The results suggest that it is worth applying FOCUS-PDCA more widely.


RESUMO Objetivo: Investigar o efeito do procedimento FOCUS-PDCA na habilidade de autocuidado de pacientes submetidos a colostomia por câncer retal. Método: Um ensaio clínico não randomizado com 160 pacientes com câncer retal submetidos a colostomia. O grupo controle recebeu intervenção de enfermagem de rotina, e o grupo observação recebeu o procedimento FOCUS-PDCA. A capacidade de autocuidado dos dois grupos foi investigada por 1 semana e 1 mês após a cirurgia, e foi feita uma análise comparativa entre os grupos. Resultados: Em uma semana após a cirurgia a capacidade de autocuidado de pacientes com câncer retal com colostomia aumentou de 39,09 pontos antes da implementação do procedimento FOCUS-PDCA para 60,15 pontos após a implementação; um aumento de 21,06%. Em um mês após a cirurgia, a capacidade de autocuidado aumentou de 61,50 pontos para 83,13 pontos após a implantação do procedimento FOCUS-PDCA; um aumento de 21,63%. Conclusão: A aplicação do procedimento FOCUS-PDCA melhorou a capacidade de autocuidado de pacientes com câncer retal submetidos a colostomia, melhorou sua saúde física e mental, reduziu as complicações da colostomia e melhorou sua qualidade de vida. Os resultados sugerem que vale a pena aplicar o FOCUS-PDCA de forma mais ampla.


RESUMEN Objetivo: Investigar el efecto del procedimiento FOCUS-PDCA sobre la capacidad de autocuidado de pacientes sometidos a colostomia por cáncer de recto. Método: Un ensayo controlado no aleatorizado de 160 pacientes con cáncer de recto sometidos a colostomia. El grupo de control recibió una intervención de enfermería de rutina y el grupo de observación recibió el procedimiento FOCUS-PDCA. La capacidad de autocuidado de los dos grupos se investigó 1 semana y 1 mes después de la cirugía, y se realizó un análisis comparativo entre los grupos. Resultados: En una semana después de la cirugía la capacidad de autocuidado de los pacientes con cáncer de recto con colostomía aumentó de 39,09 puntos antes de la implementación del procedimiento FOCUS-PDCA a 60,15 puntos después de la implementación; un aumento del 21,06%. En un mes después de la cirugía, la capacidad de autocuidado aumentó de 61,50 puntos a 83,13 puntos después de la implementación del procedimiento FOCUS-PDCA; un aumento del 21,63%. Conclusión: La aplicación del procedimiento FOCUS-PDCA mejoró la capacidad de autocuidado de los pacientes con cáncer de recto sometidos a colostomía, mejoró su salud física y mental, redujo las complicaciones de la colostomía y mejoró su calidad de vida. Los resultados sugieren que vale la pena aplicar FOCUS-PDCA de manera más amplia.


Assuntos
Neoplasias Retais , Autocuidado , Enfermagem Oncológica , Aptidão , Colostomia , Gestão da Qualidade Total
10.
Science ; 354(6316): 1156-1160, 2016 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-27738012

RESUMO

A single hematopoietic stem cell (HSC) is capable of reconstituting hematopoiesis and maintaining homeostasis by balancing self-renewal and cell differentiation. The mechanisms of HSC division balance, however, are not yet defined. Here we demonstrate, by characterizing at the single-cell level a purified and minimally heterogeneous murine Tie2+ HSC population, that these top hierarchical HSCs preferentially undergo symmetric divisions. The induction of mitophagy, a quality control process in mitochondria, plays an essential role in self-renewing expansion of Tie2+ HSCs. Activation of the PPAR (peroxisome proliferator-activated receptor)-fatty acid oxidation pathway promotes expansion of Tie2+ HSCs through enhanced Parkin recruitment in mitochondria. These metabolic pathways are conserved in human TIE2+ HSCs. Our data thus identify mitophagy as a key mechanism of HSC expansion and suggest potential methods of cell-fate manipulation through metabolic pathways.


Assuntos
Autorrenovação Celular , Hematopoese/fisiologia , Células-Tronco Hematopoéticas/fisiologia , Mitocôndrias/fisiologia , Mitofagia/fisiologia , Animais , Separação Celular , Ácidos Graxos/metabolismo , Proteínas de Fluorescência Verde/análise , Proteínas de Fluorescência Verde/metabolismo , Células-Tronco Hematopoéticas/química , Redes e Vias Metabólicas , Camundongos , Camundongos Endogâmicos C57BL , Mitofagia/genética , Oxirredução , Receptores Ativados por Proliferador de Peroxissomo/metabolismo , Receptor TIE-2/análise , Análise de Célula Única , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo
11.
J Biol Chem ; 291(19): 10201-9, 2016 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-26966181

RESUMO

Tumor suppressor pRb represses Skp2, a substrate-recruiting subunit of the SCF(Skp2) ubiquitin ligase. Rb1(+/-) mice incur "two-hit" pituitary tumorigenesis; Skp2(-/-);Rb1(+/-) mice do not. Rb1(-/-) embryos die on embryonic day (E) 14.5-15.5. Here, we report that Skp2(-/-);Rb1(-/-) embryos died on E11.5, establishing an organismal level synthetic lethal relationship between Rb1 and Skp2 On E10.5, Rb1(-/-) placentas showed similarly active proliferation and similarly inactive apoptosis as WT placenta, whereas Rb1(-/-) embryos showed ectopic proliferation without increased apoptosis in the brain. Combining Skp2(-/-) did not reduce proliferation or increase apoptosis in the placentas but induced extensive apoptosis in the brain. We conditionally deleted Rb1 in neuronal lineage with Nes-Cre and reproduced the brain apoptosis in E13.5 Nes-Cre;Rb1(lox/lox);Skp2(-/-) embryos, demonstrating their synthetic lethal relationship at a cell autonomous level. Nes-Cre-mediated Rb1 deletion increased expression of proliferative E2F target genes in the brains of Skp2(+/+) embryos; the increases rose higher with activation of expression of apoptotic E2F target genes in Skp2(-/-) embryos. The brain apoptosis was independent of p53 but coincident with proliferation. The highly activated expression of proliferative and apoptotic E2F target genes subsided with gradually reduced roles of Skp2 in preventing p27 protein accumulation in the brain in late gestation, allowing the embryos to reach full term with normally sized brains. These findings establish that Rb1 and Skp2 deletions are synthetic lethal and suggest how this lethal relationship might be circumvented, which could help design better therapies for pRb-deficient cancer.


Assuntos
Apoptose , Perda do Embrião , Embrião de Mamíferos , Desenvolvimento Embrionário/genética , Proteína do Retinoblastoma , Proteínas Quinases Associadas a Fase S , Animais , Apoptose/genética , Encéfalo/embriologia , Encéfalo/patologia , Fatores de Transcrição E2F/genética , Perda do Embrião/genética , Perda do Embrião/metabolismo , Perda do Embrião/patologia , Embrião de Mamíferos/metabolismo , Embrião de Mamíferos/patologia , Feminino , Deleção de Genes , Masculino , Camundongos , Camundongos Knockout , Proteína do Retinoblastoma/genética , Proteína do Retinoblastoma/metabolismo , Proteínas Quinases Associadas a Fase S/genética , Proteínas Quinases Associadas a Fase S/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
12.
J Biol Chem ; 290(9): 5797-809, 2015 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-25583987

RESUMO

p27Kip1 (p27) is an inhibitor of cyclin-dependent kinases. Inhibiting p27 protein degradation is an actively developing cancer therapy strategy. One focus has been to identify small molecule inhibitors to block recruitment of Thr-187-phosphorylated p27 (p27T187p) to SCF(Skp2/Cks1) ubiquitin ligase. Since phosphorylation of Thr-187 is required for this recruitment, p27T187A knockin (KI) mice were generated to determine the effects of systemically blocking interaction between p27 and Skp2/Cks1 on tumor susceptibility and other proliferation related mouse physiology. Rb1(+/-) mice develop pituitary tumors with full penetrance and the tumors are invariably Rb1(-/-), modeling tumorigenesis by two-hit loss of RB1 in humans. Immunization induced humoral immunity depends on rapid B cell proliferation and clonal selection in germinal centers (GCs) and declines with age in mice and humans. Here, we show that p27T187A KI prevented pituitary tumorigenesis in Rb1(+/-) mice and corrected decline in humoral immunity in older mice following immunization with sheep red blood cells (SRBC). These findings reveal physiological contexts that depend on p27 ubiquitination by SCF(Skp2-Cks1) ubiquitin ligase and therefore help forecast clinical potentials of Skp2/Cks1-p27T187p interaction inhibitors. We further show that GC B cells and T cells use different mechanisms to regulate their p27 protein levels, and propose a T helper cell exhaustion model resembling that of stem cell exhaustion to understand decline in T cell-dependent humoral immunity in older age.


Assuntos
Substituição de Aminoácidos , Inibidor de Quinase Dependente de Ciclina p27/genética , Imunidade Humoral/genética , Hipófise/metabolismo , Neoplasias Hipofisárias/genética , Proteína do Retinoblastoma/genética , Fatores Etários , Alanina/genética , Alanina/metabolismo , Animais , Linfócitos B/imunologia , Linfócitos B/metabolismo , Carcinogênese/genética , Carcinogênese/metabolismo , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , Eritrócitos/imunologia , Citometria de Fluxo , Técnicas de Introdução de Genes , Centro Germinativo/citologia , Centro Germinativo/imunologia , Centro Germinativo/metabolismo , Humanos , Imunidade Humoral/imunologia , Imuno-Histoquímica , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fosforilação , Hipófise/patologia , Neoplasias Hipofisárias/metabolismo , Proteína do Retinoblastoma/metabolismo , Proteínas Ligases SKP Culina F-Box/metabolismo , Ovinos , Linfócitos T/imunologia , Linfócitos T/metabolismo , Treonina/genética , Treonina/metabolismo
13.
Guang Pu Xue Yu Guang Pu Fen Xi ; 34(8): 2250-3, 2014 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-25474971

RESUMO

The content of multi-element in gypsum was determined by ICP-AES. The sample was pretreated by acid-soluble method or alkali-fusion method. Acid-soluble method is suitable for the determination of CaO, SOs, Al2O3, Fe2O3, MgO, K2O, Na2O, TiO2, P2O5, MnO, SrO and BaO. Alkali-fusion method is suitable for the determination of CaO, SO3, SiO2, Al2O3, Fe2O3, MgO, TiO2, P2O5, MnO, SrO, BaO and B2O3. Different series standard solutions were prepared considering the properties and content of elements and solution matrix. The limit of detection and quantification were confirmed for each element under their best analysis spectral lines. The recoveries of the two pretreatment methods were from 93% to 110%, besides that for TiO2 was 81%-87% as pretreated by acid-soluble method. All RSDs (n=6) of tests were from 0.70%-3.42%. The accuracies of CaO and SO3 with ICP-AES method were less than the chemical analysis method. The determination of CaO and SO3 with ICP-AES method is only suitable for the case of low accuracy requirement. The results showed that the method can be used for the determination of multi-element contents in gypsum, with simple operation, fast analysis and reliable results. Total elements can be analysed with both acid-soluble method and alkali-fusion method.

14.
Nat Commun ; 5: 3463, 2014 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-24632684

RESUMO

One mechanism of tumour suppression by pRb is repressing E2F1. Hence, E2f1 deletion diminishes tumorigenesis following Rb1 loss. However, E2F1 promotes both proliferation and apoptosis. It therefore remains unclear how de-repressed E2F1 promotes tumorigenesis. Another mechanism of pRb function is repressing Skp2 to elevate p27 to arrest proliferation. However, Skp2 deletion induced apoptosis, not proliferation arrest, in Rb1-deficient pituitary tumorigenesis. Here we show that Rb1 deletion induces higher expression of E2F1 target genes in the absence of Skp2. E2F1 binds less cyclin A but more target promoters when Rb1 is deleted with Skp2 knockout or p27T187A knockin, suggesting that stabilized p27 prevents cyclin A from binding and inhibiting E2F1. In Rb1-deficient pituitary tumorigenesis, Skp2 deletion or p27T187A mutation converts E2F1's role from proliferative to apoptotic. These findings delineate a pRb-Skp2-p27-cyclin A-E2F1 pathway that determines whether E2F1 is proliferative or apoptotic in Rb1-deficient tumorigenesis.


Assuntos
Apoptose , Regulação para Baixo , Fator de Transcrição E2F1/metabolismo , Neoplasias/genética , Neoplasias/metabolismo , Proteína do Retinoblastoma/deficiência , Proteínas Quinases Associadas a Fase S/metabolismo , Animais , Proliferação de Células , Fator de Transcrição E2F1/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos Knockout , Neoplasias/fisiopatologia , Hipófise/metabolismo , Proteína do Retinoblastoma/genética , Proteínas Quinases Associadas a Fase S/genética
15.
Cancer Cell ; 24(5): 645-59, 2013 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-24229711

RESUMO

pRb and p53 are two major tumor suppressors. Here, we found that p53 activates expression of Pirh2 and KPC1, two of the three ubiquitin ligases for p27. Loss of p53 in the absence of Skp2, the third ubiquitin ligase for p27, shrinks the cellular pool of p27 ubiquitin ligases to accumulate p27 protein. In the absence of pRb and p53, p27 was unable to inhibit DNA synthesis in spite of its abundance, but could inhibit division of cells that maintain DNA replication with rereplication. This mechanism blocked pRb/p53 doubly deficient pituitary and prostate tumorigenesis lastingly coexistent with bromodeoxyuridine-labeling neoplastic lesions, revealing an unconventional cancer cell vulnerability when pRb and p53 are inactivated.


Assuntos
Carcinogênese/genética , Inibidor de Quinase Dependente de Ciclina p27/fisiologia , Neoplasia Prostática Intraepitelial/genética , Neoplasias da Próstata/genética , Proteína do Retinoblastoma/metabolismo , Proteínas Quinases Associadas a Fase S/genética , Proteína Supressora de Tumor p53/metabolismo , Animais , Apoptose , Carcinogênese/metabolismo , Linhagem Celular Tumoral , Senescência Celular , Replicação do DNA , Deleção de Genes , Humanos , Masculino , Camundongos , Camundongos da Linhagem 129 , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Neoplasias Hipofisárias/genética , Neoplasias Hipofisárias/patologia , Neoplasia Prostática Intraepitelial/patologia , Neoplasias da Próstata/patologia , Proteína do Retinoblastoma/genética , Proteína Supressora de Tumor p53/genética , Ubiquitina-Proteína Ligases/metabolismo
17.
J Autoimmun ; 29(2-3): 106-15, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17606364

RESUMO

Immune responses against heat shock protein 60 (HSP60) of pathogen-origin are thought to be defensive events which, due to molecular mimicry, misdirect to a human counterpart. Therefore, atherosclerosis may be serologically predicted by anti-HSP60 antibodies (Abs). In the present study, we analyzed the clinical prevalence of the serum IgG Abs against Helicobacter pylori (Hp)-derived HSP60 (Hp-HSP60) or its peptide fragments in patients with cardiovascular disease (CVD; n=250), as compared to those in age- and gender-matched non-CVD patients (n=293). Anti-Hp cell lysate Abs frequently appeared in Hp-infected patients who were not associated with CVD. In contrast, Abs against the particular amino acid sequence Hp-HSP60(II3) (II3 region, Glu(141)-Leu(160), in Hp-HSP60) predominantly appeared in CVD patients, as well as IgG anti-human HSP60 (Hu-HSP60(w)). Furthermore, neither titer of anti-Hp-HSP60(II3) nor anti-Hu-HSP60(w) Abs was correlated with the levels of high sensitivity C-reactive protein (hsCRP). This data strongly suggested that IgG anti-Hp-HSP60(II3) Abs cross-reacted with Hu-HSP60(w) were independent diagnostic markers relevant to CVD. Further, the 20 amino acid residues (Glu(141)-Leu(160)) might be predominant CVD-associated epitopes that induce anti-Hu-HSP60 auto-Abs, whose location was predicted in the tertiary structure of Hu-HSP60.


Assuntos
Anticorpos Antibacterianos/imunologia , Antígenos de Bactérias/imunologia , Doenças Cardiovasculares/imunologia , Chaperonina 60/imunologia , Infecções por Helicobacter/imunologia , Helicobacter pylori/imunologia , Idoso , Idoso de 80 Anos ou mais , Sequência de Aminoácidos , Anticorpos Antibacterianos/sangue , Autoimunidade , Biomarcadores/sangue , Proteína C-Reativa/imunologia , Proteína C-Reativa/metabolismo , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/microbiologia , Chaperonina 60/metabolismo , Reações Cruzadas , Feminino , Infecções por Helicobacter/microbiologia , Helicobacter pylori/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular
18.
Microbiology (Reading) ; 151(Pt 11): 3739-3747, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16272395

RESUMO

Clostridium botulinum type B strain produces two forms of progenitor toxin, 16S and 12S. The 12S toxin is formed by association of a neurotoxin (NTX) and a non-toxic non-haemagglutinin (NTNH), and the 16S toxin is formed by conjugation of the 12S toxin with a haemagglutinin (HA). HA consists of four subcomponents designated HA1, HA2, HA3a and HA3b. When mice were immunized with formalin-detoxified NTX, 12S or 16S, a significantly greater amount of anti-NTX antibody (Ab) was produced in the mice injected with 16S than in NTX- or 12S-injected mice. Immunization with NTX mixed with HA1 and/or HA3b also increased the anti-NTX Ab production, whereas NTX mixed with HA2 did not, indicating that HA1 and HA3b have adjuvant activity. This was further confirmed by immunizing mice with human albumin (Alb) alone or Alb mixed with either HA1 or HA3b. When mouse-spleen cells were stimulated with NTX, 16S or different HA subcomponents, 16S, HA1, HA3b and the mixture of HA1 and HA3 significantly increased interleukin 6 (IL6) production compared with NTX alone. Transcription of IL6 mRNA was low after stimulation with NTX alone, but increased to 16S-stimulation levels when NTX was mixed with HA1 or HA3b. In flow cytometry using labelled Abs against CD3 and CD19, the percentage of CD19 cells was higher following stimulation with 16S or NTX mixed with HA1 or HA3b compared with stimulation with NTX. The percentage of CD3 cells remained unchanged. These results suggest strongly that HA1 and HA3b demonstrate adjuvant activity via increasing IL6 production.


Assuntos
Adjuvantes Imunológicos , Anticorpos Antibacterianos/sangue , Toxinas Bacterianas/química , Toxinas Bacterianas/imunologia , Clostridium botulinum tipo B/imunologia , Hemaglutininas/química , Hemaglutininas/imunologia , Animais , Anticorpos Antibacterianos/biossíntese , Toxinas Bacterianas/administração & dosagem , Clostridium botulinum tipo B/genética , Feminino , Hemaglutininas/administração & dosagem , Humanos , Imunização , Camundongos , Camundongos Endogâmicos BALB C , Dados de Sequência Molecular
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