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1.
Sci Rep ; 14(1): 4021, 2024 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-38369554

RESUMO

Allergic rhinitis (AR) remains a major health problem worldwide. Compared with traditional oral drugs, nasal administration avoids first-pass metabolism and achieve faster and more effective efficacy. In this study, we used the ion crosslinking method to prepare quercetin-chitosan nasal adaptive nanomedicine (QCS) delivery system and evaluated in the treatment of allergic rhinitis mice models. The obtained positively charged nanoparticles with a particle size of 229.2 ± 0.2 nm have excellent characteristics in encapsulation efficiency (79.604%), drug loading rate (14.068%), drug release (673.068 µg) and stability(> 7 days). Excitingly, QCS treatment significantly reduced the number of sneezing and nasal rubbing events in AR mice, while reducing the levels of inflammatory factors such as immunoglobulin E (IgE), interleukin (IL)-17, tumor necrosis factor (TNF)-α, and (IL)-6 to alleviate AR symptoms. Hematoxylin-eosin (HE) staining also showed the damaged nasal mucosa was improved. These experimental results suggest that QCS can effectively suppress allergic inflammation in a mouse model and hold promise as a therapeutic option for allergic rhinitis.


Assuntos
Quitosana , Nanopartículas , Rinite Alérgica , Camundongos , Animais , Quitosana/farmacologia , Quercetina/farmacologia , Rinite Alérgica/metabolismo , Mucosa Nasal/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Modelos Animais de Doenças , Camundongos Endogâmicos BALB C , Ovalbumina/metabolismo , Citocinas/metabolismo
2.
J Vis Exp ; (199)2023 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-37811950

RESUMO

Allergic rhinitis (AR) is a chronic, non-infectious inflammatory disease of the nasal mucosa, primarily mediated by specific immunoglobulin E (IgE), affecting approximately 10%-20% of the world's population. While immunofluorescence (IF) staining has long been a standard technique for detecting disease-specific protein expression, conventional IF techniques are limited in their ability to detect the expression levels of three or more proteins in the same sample. Consequently, multicolor IF techniques have been developed in recent years, which allow the simultaneous labeling of multiple targets in cells or tissues. This protocol provides a comprehensive overview of the process for establishing a rat model of AR, obtaining nasal mucosal samples, and the technical procedures for multicolor immunofluorescence. All rats in the AR group exhibited typical symptoms such as sneezing, a runny nose, and an itchy nose, with behavioral observations scoring ≥5 points. Hematoxylin and eosin (H&E) staining revealed increased inflammatory cell counts and disrupted nasal mucosal integrity in the AR group. Multicolor immunofluorescence (mIF) demonstrated increased expression of RORγt and TICAM-1, while Foxp3 expression decreased in the nasal mucosa tissue of AR rats.


Assuntos
Rinite Alérgica , Ratos , Animais , Mucosa Nasal , Imunoglobulina E , Corantes , Modelos Animais de Doenças , Ovalbumina
3.
BMC Surg ; 23(1): 185, 2023 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-37386393

RESUMO

OBJECTIVE: Enhanced recovery after surgery (ERAS) has significant effects in gastrointestinal surgery, urology, and orthopedic department, but the application of ERAS in liver cancer patients undergoing hepatectomy is less reported. This study aims to identify the effectiveness and safety of ERAS in liver cancer patients undergoing hepatectomy. METHODS: Patients who performed ERAS and no-ERAS after hepatectomy due to liver cancer from 2019 to 2022 were prospectively and retrospectively collected, respectively. Preoperative baseline data, surgical characteristics, and postoperative outcomes of patients in ERAS and non-ERAS groups were compared and analyzed. Logistic regression analysis was conducted to identify the risk factors of complications occurrence and prolonged hospital stay. RESULTS: In total, 318 patients were included in the study, 150 and 168 individuals in the ERAS group and non-ERAS group, respectively. The preoperative baseline and surgical characteristics between the ERAS and non-ERAS groups were comparable and not statistically different. Postoperative visual analogue scale pain score, the median day of gastrointestinal function recovery postoperative, complications rate, and postoperative hospitalization days were lower in the ERAS group than in the non-ERAS group. In addition, multivariate logistic regression analysis found that the implementation of the ERAS was an independent protective factor for prolonged hospitalization stay and complications occurrence. The rate of rehospitalization after discharge (< 30 days) in the ERAS group was lower than that in the non-ERAS group, but there was no statistical difference between the two groups. CONCLUSIONS: The application of ERAS in hepatectomy for patients with liver cancer is safe and effective. It can accelerate gastrointestinal function recovery postoperative, shorten the length of hospital stay, and reduce postoperative pain and complications.


Assuntos
Recuperação Pós-Cirúrgica Melhorada , Neoplasias Hepáticas , Humanos , Hepatectomia , Estudos Retrospectivos , Centros de Atenção Terciária , China/epidemiologia , Neoplasias Hepáticas/cirurgia , Complicações Pós-Operatórias/epidemiologia
4.
Microb Pathog ; 153: 104778, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33548483

RESUMO

Mycobacterium tuberculosis (Mtb) infection is the major cause of tuberculosis. Mtb regions of difference (RD) genes are vital for survival of the pathogen within hosts and for the attenuation of the bacillus Calmette-Guérin vaccine. However, the function of most RD proteins largely remains unexplored. In the present study, we focused on Rv1515c, an RD6 member from M. tuberculosis, and characterised it as a cell surface-associated protein that functions in disrupting the cytokine profile and promoting endoplasmic reticulum stress-mediated apoptosis. Rv1515c expression in M. smegmatis, a nonpathogenic species, resulted in enhanced resistance of the bacterium to various in vitro stressors (such as low pH, sodium dodecyl sulfate, oxidative pressure, and nitrogen intermediate) and its cellular survival within macrophages. Our study is the first to identify the role of Rv1515c in the physiology and pathogenesis of mycobacterium.


Assuntos
Mycobacterium tuberculosis , Tuberculose , Proteínas de Bactérias/genética , Interações Hospedeiro-Patógeno , Humanos , Macrófagos , Mycobacterium smegmatis/genética , Mycobacterium tuberculosis/genética
5.
Curr Med Sci ; 40(1): 117-122, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32166673

RESUMO

This study was conducted to compare the feasibility, safety and effectiveness of the combined-laparoscopic splenectomy and esophagogastric devascularization (C-LSED) with open splenectomy and esophagogastric devascularization surgery (OSED) in patients with portal hypertension due to liver cirrhosis. From February 2014 to June 2018, 68 patients with portal hypertension were diagnosed as having serious gastroesophageal varices and/or hypersplenism in our center. Thirty patients underwent C-LSED and 38 patients received OSED. Results and outcomes were compared retrospectively. No patients of C-LSED group required an intraoperative conversion to open surgery. Significantly shorter operating time, less blood loss, lower transfusion rates, shorter postoperative hospital stay, lower rates of complications were found in C-LSED group than in C-LSED group (P<0.05). No death and rebleeding were documented in both groups during the follow-up periods of one year. Postoperative endoscopy revealed that varices in the patients of both groups were alleviated significantly from severe to mild, and in a part of cases, the varices disappeared. The final results suggest that the C-LSED technique is superior to open procedure, due to slightly invasive, simplified operative procedure, significantly shorter operating time, less intraoperative bleeding and lower post-operative complication rates. And C-LSED offers comparable long-term effects to open surgery.


Assuntos
Hipertensão Portal/cirurgia , Laparoscopia/métodos , Cirrose Hepática/complicações , Esplenectomia/métodos , Adulto , Perda Sanguínea Cirúrgica/estatística & dados numéricos , Feminino , Humanos , Hipertensão Portal/etiologia , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Duração da Cirurgia , Estudos Retrospectivos
6.
Gastroenterol Res Pract ; 2019: 2623749, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30863438

RESUMO

PURPOSE: This study was conducted to introduce a novel modified surgical technique for laparoscopic splenectomy and esophagogastric devascularization (LSED) and its safety and efficiency. METHODS: From June 2016 to November 2017, 86 patients were diagnosed with portal hypertension and serious gastroesophageal varices in our center. Of them, 32 patients underwent LSED and 54 received the modified LSED. Results and outcomes were compared retrospectively. RESULTS: There were no significant differences in preoperative patient characteristics of the two groups. No intraoperative deaths took place in both groups. The intraoperative blood loss was apparently less in the M-LSED group (P < 0.05). There was no conversion in the M-LSED group; four patients receiving LSED were converted to hand-assisted LSED due to profuse bleeding during operation (P < 0.05). Operation time was significantly shorter in the M-LSED group (P < 0.05). Otherwise, postoperative hospital stay was shorter in the M-LSED group (P < 0.05). There were no significant differences in postoperative complications between the two groups (P > 0.05). CONCLUSIONS: Our study showed that the modified LSED was a safe and effective approach with low conversion rate, less intraoperative bleeding, less blood transfusion, and shorter operation time and postoperative hospital stay compared with classical LSED. Moreover, this technique is relatively easy and technically feasible.

7.
BMC Cancer ; 18(1): 835, 2018 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-30126375

RESUMO

BACKGROUND: This study explored the effect of liver resection on perioperative circulating tumor cells (CTCs) and found that the prognostic significance of surgery was associated with changes in CTC counts in patients with hepatocellular carcinoma (HCC). METHODS: One hundred thirty-nine patients with HCC were consecutively enrolled. The time-points for collecting blood were one day before operation and three days after operation. CTCs in the peripheral blood were detected by the CellSearch™ System. RESULTS: Both CTC detection incidence and mean CTC counts showed greater increases postoperatively (54%, mean 1.54 cells) than preoperatively (43%, mean 1.13 cells). The postoperative CTC counts increased in 41.7% of patients, decreased in 25.2% of patients and did not change in 33.1% of patients. The increase in postoperative CTC counts was significantly associated with the macroscopic tumor thrombus status. Patients with increased postoperative CTC counts (from preoperative CTC < 2 to postoperative CTC ≥ 2) had significantly shorter disease-free survival (DFS) and overall survival (OS) than did patients with persistent CTC < 2. Patients with persistent CTC levels of ≥2 had the worst prognoses. CONCLUSIONS: Surgical liver resection is associated with an increase in CTC counts, and increased postoperative CTC numbers are associated with a worse prognosis in patients with HCC.


Assuntos
Biomarcadores Tumorais/sangue , Carcinoma Hepatocelular/cirurgia , Hepatectomia/efeitos adversos , Neoplasias Hepáticas/cirurgia , Células Neoplásicas Circulantes , Adulto , Idoso , Idoso de 80 Anos ou mais , Contagem de Células Sanguíneas/métodos , Carcinoma Hepatocelular/sangue , Carcinoma Hepatocelular/patologia , Intervalo Livre de Doença , Feminino , Humanos , Fígado/patologia , Fígado/cirurgia , Neoplasias Hepáticas/sangue , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade
8.
J Surg Res ; 213: 184-190, 2017 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-28601313

RESUMO

BACKGROUND: The key points in hepatectomy are reducing blood loss and preservation of hepatic function. The aim of this study was to compare the perioperative outcomes of partial hepatectomy using two techniques of hepatic vascular inflow occlusion. MATERIALS AND METHODS: A total of 1817 patients were selected from our multi-institutional hepatectomy database in China and classified into two groups: the hemihepatic inflow occlusion (HIO) group (n = 1693) and the ipsilateral portal vein branch occlusion (IPVBO) group (n = 124). Propensity score matching of patients in a ratio of 1:1 was conducted. The primary outcome was intraoperative blood loss. Secondary outcomes were postoperative liver function, postoperative morbidity and mortality, and duration of hospital stay after surgery. RESULTS: After propensity score matching, there were 124 patients in the IPVBO group and the HIO group, respectively. There were no significant differences between the two groups regarding intraoperative blood loss, blood transfusion requirement, operating time, postoperative morbidity and mortality, and duration of hospital stay after surgery (P > 0.05). However, The IPVBO group was associated with significantly lower peak in postoperative ALT level than the HIO group (P < 0.05). CONCLUSIONS: The results indicated that IPVBO did not lead to more intraoperative blood loss compared with HIO, and it decreased the peak of postoperative ALT level. In terms of postoperative morbidity and mortality, duration of hospital stay after surgery, IPVBO was also equal to HIO. Thus, IPVBO could be an alternative method of hepatic inflow occlusion.


Assuntos
Perda Sanguínea Cirúrgica/prevenção & controle , Hemostasia Cirúrgica/métodos , Hepatectomia/métodos , Adulto , Idoso , Bases de Dados Factuais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Veia Porta , Pontuação de Propensão , Estudos Retrospectivos , Resultado do Tratamento
9.
J Mol Cell Biol ; 9(3): 243-255, 2017 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-27913571

RESUMO

Small nucleolar RNA (snoRNA) dysfunctions have been associated with cancer development. SNORD126 is an orphan C/D box snoRNA that is encoded within introns 5-6 of its host gene, cyclin B1-interacting protein 1 (CCNB1IP1). The cancer-associated molecular mechanisms triggered by SNORD126 are not fully understood. Here, we demonstrate that SNORD126 is highly expressed in hepatocellular carcinoma (HCC) and colorectal cancer (CRC) patient samples. SNORD126 increased Huh-7 and SW480 cell growth and tumorigenicity in nude mice. Knockdown of SNORD126 inhibited HepG2 and LS174T cell growth. We verified that SNORD126 was not processed into small RNAs with miRNA activity. Moreover, SNORD126 did not show a significant expression correlation with CCNB1IP1 in HCC samples or regulate CCNB1IP1 expression. Our gene expression profile analysis indicated that SNORD126-upregulated genes frequently mapped to the PI3K-AKT pathway. SNORD126 overexpression increased the levels of phosphorylated AKT, GSK-3ß, and p70S6K and elevated fibroblast growth factor receptor 2 (FGFR2) expression. siRNA-mediated knockdown or AZD4547-mediated inactivation of FGFR2 in SNORD126-overexpressing Huh-7 cells inhibited AKT phosphorylation and suppressed cell growth. These findings indicate an oncogenic role for SNORD126 in cancer and suggest its potential as a therapeutic target.


Assuntos
Carcinoma Hepatocelular/patologia , Neoplasias Colorretais/patologia , Neoplasias Hepáticas/patologia , RNA Nucleolar Pequeno/metabolismo , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/metabolismo , Animais , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Proliferação de Células , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Resistencia a Medicamentos Antineoplásicos/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Masculino , Camundongos Nus , Pessoa de Meia-Idade , Análise de Sequência com Séries de Oligonucleotídeos , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Nucleolar Pequeno/genética , Ensaios Antitumorais Modelo de Xenoenxerto
10.
Sci China Life Sci ; 59(10): 995-1005, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27585922

RESUMO

Hepato-pancreato-biliary (HPB) tumors are common in China. However, these tumors are often diagnosed at intermediate/ advanced stages because of the lack of a systemic surveillance program in China. This situation creates many technical challenges for surgeons and increases the incidence of postoperative complications. Therefore, Dr. Xiao-Ping Chen has made many important technical improvements, such as Chen's hepatic portal occlusion method, the anterior approach for liver resection of large HCC tumors, the modified technique of Belghiti's liver-hanging maneuver, inserting biliary-enteric anastomosis technique, and invaginated pancreaticojujunostomy with transpancreatic U-sutures. These techniques are simple, practical, and easy to learn. Owing to these advantages, complicated surgical procedures can be simplified, and the curative effects are greatly improved. These improved techniques have been widely applied in China and will benefit many additional patients. In this review, we introduce our experience of surgically treating intermediate/advanced hepatocellular carcinoma (HCC), hilar cholangiocarcinoma (HC), and pancreatic carcinoma, mainly focusing on technical innovations established by Dr. Chen in HPB surgery.


Assuntos
Carcinoma Hepatocelular/cirurgia , Procedimentos Cirúrgicos do Sistema Digestório/métodos , Tumor de Klatskin/cirurgia , Neoplasias Hepáticas/cirurgia , Neoplasias Pancreáticas/cirurgia , China , Procedimentos Cirúrgicos do Sistema Digestório/normas , Intervalo Livre de Doença , Humanos , Masculino , Cirurgiões/normas
11.
Sci Rep ; 6: 28002, 2016 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-27349953

RESUMO

Novel factors involved in Mycobacteria antibiotics resistance are crucial for better targets to combat the ever-increasing drug resistant strains. Mycobacterium tuberculosis Rv1152, a novel GntR family transcriptional regulator and a promising vancomycin adjuvant target, was firstly characterized in our study. Overexpression of Rv1152 in Mycobacterium smegmatis decreased bacterial susceptibility to vancomycin. Moreover, a deficiency in MSMEG_5174, an Rv1152 homolog made M. smegmatis more sensitive to vancomycin, which was reverted by complementing the MSMEG_5174 deficiency with Rv1152 of M. tuberculosis. Rv1152 negatively regulated four vancomycin responsive genes, namely genes encoding the ribosome binding protein Hsp, small unit of sulfate adenylyltransferase CysD, L-lysine-epsilon aminotransferase Lat, and protease HtpX. Taken together, Rv1152 controls the expression of genes required for the susceptibility to vancomycin. This is the first report that links the GntR family transcriptional factor with vancomycin susceptibility. Inhibitors of Rv1152 might be ideal vancomycin adjuvants for controlling multi-drug resistant Mycobacterial infections.


Assuntos
Regulação da Expressão Gênica/fisiologia , Mycobacterium tuberculosis , Fatores de Transcrição , Resistência a Vancomicina/genética , Mycobacterium smegmatis/genética , Mycobacterium smegmatis/metabolismo , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
12.
Cancer Lett ; 376(1): 188-96, 2016 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-26996299

RESUMO

Anoikis, a form of programmed cell death, occurs when the cells are detached from the appropriate extracellular matrix. Anoikis resistance or anchorage independence is necessary for distant metastases of cancer. The mechanisms by which hepatocellular carcinoma (HCC) cells become resistant to anoikis are not fully understood. Integrin beta4 (ITGB4, also known as CD104) is associated with progression of many human cancers. In this study, we demonstrate that ITGB4 is over-expressed in HCC tissues and aggressive HCC cell lines. To explore the role of ITGB4 in HCC, we inhibited its expression using small interfering RNA in two HCC cell lines: HCCLM3 and HLF. We show that knockdown of ITGB4 significantly enhanced susceptibility to anoikis through inhibition of AKT/PKB signaling. Moreover, ITGB4 interacts with epidermal growth factor receptor (EGFR) in a ligand independent manner. Inactivation of EGFR inhibits the anchorage independence and AKT pathway promoted by ITGB4. Further investigation proved that the ITGB4-EGFR unit triggers the focal adhesion kinase (FAK) to activate the AKT signaling pathway. Finally, we demonstrate that over-expression of ITGB4 is positively associated with tumor growth and lung metastases of HCC in vivo. Collectively, we demonstrate for the first time that ITGB4 is overexpressed in HCC tissues and promotes metastases of HCC by conferring anchorage independence through EGFR-dependent FAK-AKT activation.


Assuntos
Anoikis , Carcinoma Hepatocelular/enzimologia , Receptores ErbB/metabolismo , Quinase 1 de Adesão Focal/metabolismo , Integrina beta4/metabolismo , Neoplasias Hepáticas/enzimologia , Neoplasias Pulmonares/enzimologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Adulto , Idoso , Animais , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/secundário , Proliferação de Células , Ativação Enzimática , Feminino , Regulação Neoplásica da Expressão Gênica , Células Hep G2 , Xenoenxertos , Humanos , Integrina beta4/genética , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/secundário , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , Pessoa de Meia-Idade , Transplante de Neoplasias , Proteínas Proto-Oncogênicas c-akt/genética , Interferência de RNA , Transdução de Sinais , Transfecção , Carga Tumoral
13.
J Drug Target ; 24(5): 392-8, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26548775

RESUMO

Traditionally eukaryotes exclusive cytoskeleton has been found in bacteria and other prokaryotes. FtsZ, MreB and CreS are bacterial counterpart of eukaryotic tubulin, actin filaments and intermediate filaments, respectively. FtsZ can assemble to a Z-ring at the cell division site, regulate bacterial cell division; MreB can form helical structure, and involve in maintaining cell shape, regulating chromosome segregation; CreS, found in Caulobacter crescentus (C. crescentus), can form curve or helical filaments in intracellular membrane. CreS is crucial for cell morphology maintenance. There are also some prokaryotic unique cytoskeleton components playing crucial roles in cell division, chromosome segregation and cell morphology. The cytoskeleton components of Mycobacterium tuberculosis (M. tuberculosis), together with their dynamics during exposure to antibiotics are summarized in this article to provide insights into the unique organization of this formidable pathogen and druggable targets for new antibiotics.


Assuntos
Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Bactérias/metabolismo , Citoesqueleto/efeitos dos fármacos , Citoesqueleto/metabolismo , Proteínas de Bactérias/metabolismo , Divisão Celular/efeitos dos fármacos
14.
J Biomol Struct Dyn ; 34(3): 585-99, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26156642

RESUMO

Mycobacterium tuberculosis cAMP and underlying regulatory network are crucial for its survival and thrive in the presence of numerous stresses mounted by the host. Our studies mainly focus on the cAMP-induced M. tuberculosis gene Rv1265, which was shown to be up-regulated under hypoxia and during macrophage infection by addition of exogenous cAMP. To explore the role of Rv1265 in host-pathogen interactions, Rv1265 was expressed in a non-pathogenic Mycobacterium smegmatis. We found that Rv1265 was associated with cell envelope and can up-regulate some cell wall fatty acid components, especially the C26:0. The survival of the recombinant Ms_Rv1265 was enhanced within macrophages and under stress conditions such as low pH and SDS. Macrophages infected with Ms_Rv1265 increased transcription of pro-inflammatory cytokines IL-1ß, IL-6, and IL-12 P40 and anti-inflammatory cytokine IL-10 possibly through activation of NF-κB and ERK1/2 pathway. Our findings indicate that Rv1265 can enhance mycobacterial survival within macrophages, and perturb the cytokine profile of macrophage.


Assuntos
Proteínas de Bactérias/metabolismo , Citocinas/metabolismo , Macrófagos/microbiologia , Macrófagos/fisiologia , Viabilidade Microbiana , Mycobacterium tuberculosis/fisiologia , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Parede Celular/metabolismo , Ácidos Graxos/metabolismo , Expressão Gênica , Sistema de Sinalização das MAP Quinases , Mycobacterium smegmatis/genética , Mycobacterium smegmatis/metabolismo , NF-kappa B/metabolismo , Ligação Proteica , Transporte Proteico , Transdução de Sinais , Estresse Fisiológico
15.
Infect Genet Evol ; 40: 295-301, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26498723

RESUMO

Clustered regularly interspaced short palindromic repeats (CRISPR) are present in the genome of 40% bacteria and 90% archaea. CRISPR and accompanying Cas proteins constitute an adaptive immune system against disruptive mobile genetic elements. Two CRISPRs and 9 genes encoding CRISPR-associated proteins have been found in the genome of Mycobacterium tuberculosis. The CRISPR-associated Cas2 is an endoribonuclease required for the acquisition of new spacers. In this study, Cas2 encoded by Rv2816c was expressed in Mycobacterium smegmatis lacking CRISPR-Cas system and its role in stress responses of M. smegmatis in vitro and within macrophages was studied. We found that Cas2 mediated M. smegmatis stress response changes were associated with the altered expression of sigma factors which involved in mycobacterial stress response and virulence. We also found that Cas2 decreased the survival of M. smegmatis within macrophages. This study provides new insights on the role of Cas2.


Assuntos
Sistemas CRISPR-Cas , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Regulação Bacteriana da Expressão Gênica , Macrófagos/microbiologia , Mycobacterium smegmatis/fisiologia , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/metabolismo , Estresse Fisiológico/genética , Sequência de Aminoácidos , Animais , Antibacterianos/farmacologia , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Linhagem Celular , Sobrevivência Celular , Humanos , Camundongos , Testes de Sensibilidade Microbiana , Viabilidade Microbiana , Mycobacterium smegmatis/citologia , Mycobacterium tuberculosis/efeitos dos fármacos , Fenótipo , Fator sigma/genética , Fator sigma/metabolismo , Transcrição Gênica
16.
Crit Rev Eukaryot Gene Expr ; 25(4): 349-62, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26559095

RESUMO

Epigenetics of genes associated with tuberculosis susceptibility such as DNA methylation, posttranslational histone modifications, and non-coding RNA remain largely untapped field for better tuberculosis control. Many genes involved in tuberculosis susceptibility (e.g., NRAMP1 (SLC11A1), IFNG, NOS2A, VDR, ISG15, TACO, TLR1, TLR, IL18R1, chemokines, PADI, DUSP14, MBL, and MASP-2) have been subjected to epigenetic modification. Our summary of these modifications provides fresh insights into the pathogenesis of tuberculosis and inspires targets discovery for host-derived therapy.


Assuntos
Epigênese Genética , Predisposição Genética para Doença , Mycobacterium tuberculosis/fisiologia , Tuberculose/genética , Tuberculose/imunologia , Animais , Citocinas/genética , Epistasia Genética , Código das Histonas , Humanos , Mutação , Interferência de RNA , Tuberculose/tratamento farmacológico , Tuberculose/microbiologia
17.
Curr Microbiol ; 71(6): 719-24, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26349576

RESUMO

Four kinds of bioprotective alkaloids-peramine, loline, ergot alkaloid, indole-diterpenes, produced by grass-fungal endophyte symbioses, are deterrents or toxic to vertebrate and invertebrate herbivores. Ergot alkaloids have pharmacological properties and widely are used clinically. The regulation of alkaloids biosynthesis is under intensive study to improve the yield for better agricultural and medicinal application. In this paper, we summarize the structure, related genes, regulation, and toxicity of alkaloids. We focus on the biosynthesis and the regulation network of alkaloids.


Assuntos
Alcaloides/biossíntese , Endófitos/metabolismo , Comportamento Alimentar/efeitos dos fármacos , Fungos/metabolismo , Regulação Fúngica da Expressão Gênica , Herbivoria/efeitos dos fármacos , Poaceae/microbiologia , Vias Biossintéticas , Endófitos/genética , Endófitos/fisiologia , Fungos/genética , Fungos/fisiologia , Simbiose
18.
Int J Surg ; 22: 15-21, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26272853

RESUMO

BACKGROUND: To investigate the safety and feasibility of a new intrahepatic cholangiojejunostomy for multiple intrahepatic biliary ductal openings after hepatobiliary resection. MATERIALS AND METHODS: Forty-eight pigs were randomly assigned into two groups: the new intrahepatic cholangiojejunostomy group (n = 24); and the control group (n = 24) with classical hepaticojejunostomy. Six pigs in each group were sacrificed on postoperative day 7, 30, 90 and 180. The primary outcomes were postoperative mortality, morbidity, and the pathological changes in the anastomoses. The secondary outcomes were levels of aspartate transaminase, bilirubin, albumin and alkaline phosphate. RESULTS: The operations were successfully carried out. The rates of anastomotic leakage and cholangitis in the study group were 0% and 8.3% (2/24), while in the control group they were 4.2% (1/24) and 20.8% (5/24), respectively. The stenotic rates of the sectional areas of the anastomotic stomas in the study group were lower than those in the control group on postoperative day 7, 30, 90 and 180 (p < 0.001, p = 0.002, p < 0.001, and p = 0.001, respectively). Under microscopy, in the study group, the anterior wall of the stoma was everted and sunken while the posterior wall was protruded in a semicircular-disc shaped. The liver transection plane was epithelialized with mucosal covering by post-operative day 30. In the control group, however, the stoma was centripetally protruded with a relative circular stenosis. CONCLUSIONS: The new intrahepatic cholangiojejunostomy is safe, simple, and convenient for multiple biliary ductal openings.


Assuntos
Ductos Biliares Intra-Hepáticos/cirurgia , Procedimentos Cirúrgicos do Sistema Biliar/métodos , Anastomose Cirúrgica , Fístula Anastomótica/etiologia , Fístula Anastomótica/prevenção & controle , Animais , Procedimentos Cirúrgicos do Sistema Biliar/efeitos adversos , Feminino , Masculino , Suínos
19.
Int J Biochem Cell Biol ; 59: 193-202, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25456444

RESUMO

N(ɛ)-Acetylation of lysine residues represents a pivotal post-translational modification used by both eukaryotes and prokaryotes to modulate diverse biological processes. Mycobacterium tuberculosis is the causative agent of tuberculosis, one of the most formidable public health threats. Many aspects of the biology of M. tuberculosis remain elusive, in particular the extent and function of N(ɛ)-lysine acetylation. With a combination of anti-acetyllysine antibody-based immunoaffinity enrichment with high-resolution mass spectrometry, we identified 1128 acetylation sites on 658 acetylated M. tuberculosis proteins. GO analysis of the acetylome showed that acetylated proteins are involved in the regulation of diverse cellular processes including metabolism and protein synthesis. Six types of acetylated peptide sequence motif were revealed from the acetylome. Twenty lysine-acetylated proteins showed homology with acetylated proteins previously identified from Escherichia coli, Salmonella enterica, Bacillus subtilis and Streptomyces roseosporus, with several acetylation sites highly conserved among four or five bacteria, suggesting that acetylated proteins are more conserved. Notably, several proteins including isocitrate lyase involved in the persistence, virulence and antibiotic resistance are acetylated, and site-directed mutagenesis of isocitrate lyase acetylation site to glutamine led to a decrease of the enzyme activity, indicating major roles of KAc in these proteins engaged cellular processes. Our data firstly provides a global survey of M. tuberculosis acetylation, and implicates extensive regulatory role of acetylation in this pathogen. This may serve as an important basis to address the roles of lysine acetylation in M. tuberculosis metabolism, persistence and virulence.


Assuntos
Proteínas de Bactérias/metabolismo , Lisina/metabolismo , Mycobacterium tuberculosis/metabolismo , Proteoma/metabolismo , Proteômica/métodos , Acetilação , Motivos de Aminoácidos , Sequência de Aminoácidos , Proteínas de Bactérias/química , Sequência Conservada , Resistência Microbiana a Medicamentos , Evolução Molecular , Ontologia Genética , Humanos , Isocitrato Liase/metabolismo , Anotação de Sequência Molecular , Dados de Sequência Molecular , Mutagênese , Mycobacterium tuberculosis/patogenicidade , Peptídeos/química , Peptídeos/metabolismo , Fosforilação , Espectrometria de Massas em Tandem , Virulência
20.
J Interferon Cytokine Res ; 34(9): 686-98, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24684623

RESUMO

Tuberculosis caused by Mycobacterium tuberculosis (MTB) remains a serious global public health concern. About one-third of the global population has been latently infected with this pathogen. MTB proteases are important virulence factors and involve in subverting the host immunity. MTB protease Rv3668c was implicated in drug action and dormancy by Gene Expression Omnibus data. To define the role of Rv3668c in pathogen-host interaction, we constructed recombinant strain Mycobacterium smegmatis-Rv3668c (Ms-Rv3668c). The resultant strains were used to challenge the human macrophage cell line U937. The cytokine levels and the survival of recombinants and macrophages were monitored. The results showed that recombinant Ms-Rv3668c specifically upregulated the secretion of proinflammatory cytokines TNF-α, IL-1ß, and IL-6 and downregulated the secretion of anti-inflammatory cytokine IL-10 by U937 cells, consistent with the upregulated transcription of TNF-α and IL-1ß. Rv3668c recombinants demonstrated prolonged survival within the U937 cells and accelerated the death of the host cells. Inhibitor experiments showed that the ERK-NF-κB axis was involved in the Rv3668c-triggered TNF-α and IL-1ß changes. These results provided evidence for the engagement of Rv3668c in the interaction between Mycobacterium and host.


Assuntos
Proteínas de Bactérias/metabolismo , Citocinas/genética , Mycobacterium tuberculosis/metabolismo , NF-kappa B/metabolismo , Serina Proteases/metabolismo , Proteínas de Bactérias/genética , Linhagem Celular , Citocinas/metabolismo , Regulação para Baixo , Expressão Gênica , Interações Hospedeiro-Patógeno , Humanos , Interleucina-10/genética , Interleucina-10/metabolismo , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Interleucina-6/genética , Interleucina-6/metabolismo , Macrófagos/metabolismo , Macrófagos/microbiologia , Mycobacterium tuberculosis/enzimologia , Mycobacterium tuberculosis/genética , NF-kappa B/genética , Serina Proteases/genética , Tuberculose/genética , Tuberculose/metabolismo , Tuberculose/microbiologia , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo , Células U937 , Regulação para Cima
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