Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 7 de 7
Filtrar
1.
Brain Behav ; 12(11): e2778, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36271663

RESUMO

AIMS: Spinal cord injury (SCI) is one of the most severe neurological diseases. However, there is still no effective treatment for it. Nesfatin, a precursor neuropeptide derived from nucleobindin 2 (NUCB2), has displayed a wide range of protective effects in different types of cells and tissue. However, the effects of nesfatin-1 in SCI have not been reported before. MATERIALS AND METHODS: A SCI model was established. The behavior of mice was assessed using the Basso, Beattie, and Bresnahan (BBB) assessment. RESULTS: Here, we report that the administration of nesfatin-1 improved neurological recovery in SCI mice by increasing BBB scores, reducing lesion area volume and spinal cord water content. Also, nesfatin-1 ameliorated oxidative stress by reducing reactive oxygen species (ROS) levels and increasing superoxide dismutase (SOD) activity. We also found that nesfatin-1 prevented neuronal apoptosis in SCI mice by reducing caspase 3 activity and the expression of Bax, as well as increasing B-cell lymphoma-2 (Bcl-2). Additionally, nesfatin-1 reduced the levels of interleukin 6 (IL-6), interleukin-1ß (IL-1ß), and tumor necrosis factor-α (TNF-α). Nesfatin-1 also promoted microglia towards M2 polarization by increasing the marker CD206 but reducing CD16. Importantly, nesfatin-1 enhanced the phosphorylation of signal transducer and activator of transcription 1 (STAT1) but reduced the expression levels of toll-like receptor 4 (TLR4) and phosphorylated nuclear factor kappa-B p65 (p-NF-κB p65). CONCLUSION: Our findings imply that nesfatin-1 exerts neuroprotective actions in SCI by promoting the activation of M2 microglia, and its underlying mechanisms might be related to the activation of STAT1 and inhibition of the TLR4/NF-κB signaling pathway.


Assuntos
Doenças Neuroinflamatórias , Nucleobindinas , Traumatismos da Medula Espinal , Animais , Camundongos , NF-kappa B/metabolismo , Medula Espinal , Traumatismos da Medula Espinal/tratamento farmacológico , Traumatismos da Medula Espinal/metabolismo , Receptor 4 Toll-Like/metabolismo , Nucleobindinas/metabolismo , Neuroproteção
2.
BMC Med Inform Decis Mak ; 19(1): 198, 2019 10 22.
Artigo em Inglês | MEDLINE | ID: mdl-31640686

RESUMO

BACKGROUND: Breast cancer causes hundreds of thousands of deaths each year worldwide. The early stage diagnosis and treatment can significantly reduce the mortality rate. However, the traditional manual diagnosis needs intense workload, and diagnostic errors are prone to happen with the prolonged work of pathologists. Automatic histopathology image recognition plays a key role in speeding up diagnosis and improving the quality of diagnosis. METHODS: In this work, we propose a breast cancer histopathology image classification by assembling multiple compact Convolutional Neural Networks (CNNs). First, a hybrid CNN architecture is designed, which contains a global model branch and a local model branch. By local voting and two-branch information merging, our hybrid model obtains stronger representation ability. Second, by embedding the proposed Squeeze-Excitation-Pruning (SEP) block into our hybrid model, the channel importance can be learned and the redundant channels are thus removed. The proposed channel pruning scheme can decrease the risk of overfitting and produce higher accuracy with the same model size. At last, with different data partition and composition, we build multiple models and assemble them together to further enhance the model generalization ability. RESULTS: Experimental results show that in public BreaKHis dataset, our proposed hybrid model achieves comparable performance with the state-of-the-art. By adopting the multi-model assembling scheme, our method outperforms the state-of-the-art in both patient level and image level accuracy for BACH dataset. CONCLUSIONS: We propose a novel compact breast cancer histopathology image classification scheme by assembling multiple compact hybrid CNNs. The proposed scheme achieves promising results for the breast cancer image classification task. Our method can be used in breast cancer auxiliary diagnostic scenario, and it can reduce the workload of pathologists as well as improve the quality of diagnosis.


Assuntos
Neoplasias da Mama/patologia , Processamento de Imagem Assistida por Computador , Redes Neurais de Computação , Algoritmos , Mama/patologia , Neoplasias da Mama/classificação , Carcinoma in Situ , Simulação por Computador , Compressão de Dados , Conjuntos de Dados como Assunto , Feminino , Humanos , Invasividade Neoplásica , Sensibilidade e Especificidade
3.
J Int Med Res ; 45(2): 762-770, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28415933

RESUMO

Objective The effect of polyomavirus infection in HSCT recipients is poorly understood. Methods We evaluated 38 HSCT recipients. Polyomavirus was detected by nested qualitative polymerase chain reaction (PCR) assays of urine. The risk factors for BK virus and JC virus were analysed. The kidney and liver functions of infected and uninfected patients were compared. Results BK virus, JC virus, and simian virus 40 were detected in 21%, 42%, and 0% of HSCT recipients respectively. HCMV infection was found to be an independent risk factor for JC virus infection (odds ratio (OR): 8.528), while transplants with mismatched HLA are more susceptible to BK virus infection (OR: 12.000). Liver function of JC virus-infected subjects was worse than that of uninfected subjects. Conclusion We must be vigilant for opportunistic polyomavirus infections in HSCT recipients, especially those with HCMV co-infection or a mismatched HLA transplant. When unexplained liver function deterioration is observed, JC virus infection should be considered.


Assuntos
Vírus BK/isolamento & purificação , Transplante de Células-Tronco Hematopoéticas , Vírus JC/isolamento & purificação , Infecções por Polyomavirus/diagnóstico , Infecções Tumorais por Vírus/diagnóstico , Adolescente , Adulto , Vírus BK/genética , Criança , DNA Viral/genética , Feminino , Neoplasias Hematológicas/imunologia , Neoplasias Hematológicas/patologia , Neoplasias Hematológicas/terapia , Teste de Histocompatibilidade , Humanos , Vírus JC/genética , Rim/imunologia , Rim/fisiopatologia , Rim/virologia , Testes de Função Renal , Fígado/imunologia , Fígado/fisiopatologia , Fígado/virologia , Testes de Função Hepática , Masculino , Pessoa de Meia-Idade , Infecções por Polyomavirus/imunologia , Infecções por Polyomavirus/fisiopatologia , Infecções por Polyomavirus/virologia , Estudos Prospectivos , Fatores de Risco , Irmãos , Condicionamento Pré-Transplante/métodos , Transplante Homólogo , Infecções Tumorais por Vírus/imunologia , Infecções Tumorais por Vírus/fisiopatologia , Infecções Tumorais por Vírus/virologia , Doadores não Relacionados
4.
Gut Pathog ; 8: 47, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27785154

RESUMO

BACKGROUND: Chryseobacterium indologenes is an emerging opportunistic pathogen in hospital-acquired infection, which is intrinsically resistant to most antimicrobial agents against gram-negative bacteria. In the purpose of extending our understanding of the resistance mechanism of C. indologenes, we sequenced and analyzed the genome of an extensively antibiotic resistant C. indologenes strain, isolated from a Chinese prostate cancer patient. We also investigated the presence of antibiotic resistance genes, particularly metallo-ß-lactamase (MBL) genes, and performed a comparative genomic analysis with other Chryseobacterium species. RESULTS: 16s rRNA sequencing indicated the isolate belongs to C. indologenes. We assembled a total of 1095M bp clean-filtered reads into 171 contigs by de novo assembly. The draft genome of C. indologenes J31 consisted of 5,830,795 bp with a GC content of 36.9 %. RAST analysis revealed the genome contained 5196 coding sequences (CDSs), 28 rRNAs, 81 tRNAs and 114 pseudogenes. We detected 90 antibiotic resistance genes from different drug classes in the whole genome. Notably, a novel blaIND allele blaIND-16 was identified, which shared 99 % identity with blaIND-8 and blaIND-10. By comparing strain J31 genome to the closely four related neighbors in the genus Chryseobacterium, we identified 2634 conserved genes, and 1449 unique genes. CONCLUSIONS: In this study, we described the whole genome sequence of C. indologenes strain J31. Numerous resistance determinants were detected in the genome and might be responsible for the extensively antibiotic resistance of this strain. Comparative genomic analysis revealed the presence of considerable strain-specific genes which would contribute to the distinctive characteristics of strain J31. Our study provides the insight of the multidrug resistance mechanism in genus Chryseobacterium.

5.
Biochem Biophys Res Commun ; 478(4): 1653-9, 2016 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-27591898

RESUMO

Sortase mediated transpeptidation reactions play a significant role in covalent attachment of surface proteins to the cell wall of Gram-positive bacteria. Earlier studies have shown that sortase A (StrA) is required for the virulence of Staphylococci. The human pathogen Staphylococcus simulans CJ16 carries a putative sortase A (SsiStrA) encoding gene, but neither transpeptidation activity nor biochemical characteristics of SsiStrA have been investigated. Here, we identified and characterized StrA from coagulase-negative Staphylococci. SsiStrA was cloned and overexpressed in Escherichia coli BL21 in a soluble form. Size-exclusion chromatography, cross-linking and dynamic light scattering demonstrated that SsiStrA existed as monomer-dimer equilibrium in vitro. We further demonstrated that SsiStrA has sortase activity, and it recognized and cleaved the sorting motif LXPTG. H117, C180 and R193 residues were critical for enzyme activity, and calcium ions enhanced activity.


Assuntos
Aminoaciltransferases/metabolismo , Proteínas de Bactérias/metabolismo , Parede Celular/metabolismo , Cisteína Endopeptidases/metabolismo , Staphylococcus/enzimologia , Motivos de Aminoácidos/genética , Sequência de Aminoácidos , Aminoaciltransferases/química , Aminoaciltransferases/genética , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Sítios de Ligação/genética , Cálcio/metabolismo , Domínio Catalítico , Parede Celular/genética , Cromatografia em Gel , Dicroísmo Circular , Cisteína Endopeptidases/química , Cisteína Endopeptidases/genética , Escherichia coli/genética , Immunoblotting , Cinética , Modelos Moleculares , Domínios Proteicos , Multimerização Proteica , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Homologia de Sequência de Aminoácidos , Staphylococcus/genética , Especificidade por Substrato
6.
Medicine (Baltimore) ; 95(35): e4482, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27583858

RESUMO

BACKGROUND: Endoscopic variceal ligation (EVL) is the endoscopic treatment of acute esophageal variceal hemorrhage, however, prophylaxis antibiotic during EVL is controversial. METHODS: We reported a 60-year-old man with diabetes, liver cirrhosis and hepatocellular carcinoma who received EVL for esophageal variceal haemorrhage. RESULTS: On the second day after EVL, the patient developed fever and chills. A week after EVL, the blood cultures were viridans streptococcus positive, and echocardiogram showed a vegetation on the cardiac valve. The patient was therefore diagnosed with infective endocarditis (IE). The patient was cured after 7 weeks of intravenous piperacillin sulbactam sodium. No complications were observed during the 3-month follow-up after discharge. CONCLUSION: To our knowledge, this is the first documented case to report IE caused by viridans streptococcus after EVL. Therefore, whether prophylaxis antibiotic should be administered to cirrhotic patients receiving EVL is worth further research.


Assuntos
Endocardite Bacteriana/etiologia , Varizes Esofágicas e Gástricas/cirurgia , Hemorragia Gastrointestinal/cirurgia , Infecções Estreptocócicas , Estreptococos Viridans , Endocardite Bacteriana/microbiologia , Endoscopia Gastrointestinal/efeitos adversos , Humanos , Ligadura/efeitos adversos , Masculino , Pessoa de Meia-Idade
7.
Int J Infect Dis ; 46: 89-93, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27057748

RESUMO

BACKGROUND: Viral infections are a major cause of morbidity and mortality after hematopoietic stem cell transplantation (HSCT). The effect of herpesvirus infections in human cytomegalovirus (HCMV)-seropositive (IgG-positive/IgM-negative) HSCT recipients remains poorly understood. The risk factors associated with Epstein-Barr virus (EBV), HCMV, and human herpes virus type 6 (HHV-6) infections after HSCT, both alone and in combination, were investigated in this study. METHODS: Peripheral blood specimens were collected from 44 HSCT recipients and examined for viral DNA using quantitative fluorescence PCR assays. Risk factors for EBV, HCMV, and HHV-6 infections were analyzed by binary logistic regression, and relationships between these viruses were analyzed using the Chi-square test. RESULTS: EBV, HCMV, and HHV-6 were detected in 50%, 45.45%, and 25% of HCMV-seropositive (IgG-positive/IgM-negative) HSCT recipients, respectively. Male sex (p=0.007) and conditioning regimens including anti-thymocyte globulin (ATG) (p=0.034) were strongly associated with an increased risk of EBV infection. Graft-versus-host disease (GVHD) prophylaxis with corticosteroids was a risk factor for both EBV (p=0.013) and HCMV (p=0.040) infections, while EBV infection (p=0.029) was found to be an independent risk factor for HHV-6 infection. Pre-existing HHV-6 infection was associated with lower rates of HCMV infection (p=0.002); similarly, pre-existing HCMV infection was protective against HHV-6 infection (p=0.036). CONCLUSIONS: HCMV-seropositive (IgG-positive/IgM-negative) HSCT recipients exhibited a high rate of herpesvirus infections, particularly EBV. ATG and male sex were strongly associated with an increased risk of EBV infection. GVHD prophylaxis with prednisone was found to affect both EBV and HCMV infections. Prior infection with EBV was shown to promote HHV-6 infection. Taken together, these data highlight the need for active monitoring of herpesvirus infections in patients undergoing HSCT.


Assuntos
Infecções por Citomegalovirus/virologia , Citomegalovirus/imunologia , Infecções por Vírus Epstein-Barr/virologia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Infecções por Herpesviridae/virologia , Complicações Pós-Operatórias/virologia , Adolescente , Adulto , Anticorpos Antivirais/sangue , Citomegalovirus/genética , Citomegalovirus/isolamento & purificação , Infecções por Citomegalovirus/sangue , Infecções por Citomegalovirus/etiologia , Infecções por Vírus Epstein-Barr/sangue , Infecções por Vírus Epstein-Barr/etiologia , Feminino , Infecções por Herpesviridae/sangue , Infecções por Herpesviridae/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/sangue , Complicações Pós-Operatórias/etiologia , Transplantados/estatística & dados numéricos , Adulto Jovem
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA