Resumo A doença coronariana (DCC) tem sido associada a significativa morbidade e mortalidade em todo o mundo. Embora ainda sejam controversos, vários estudos têm demonstrado a associação de infecções por M. pneumoniae com aterosclerose. Avaliamos a possível associação de infecções por micoplasma em pacientes com diagnóstico de aterosclerose pelos métodos ELISA e PCR. Amostras de tecido aterosclerótico e amostras de sangue foram coletadas para a detecção de anticorpos contra micoplasma (IgA) por ELISA de 97 pacientes com doença arterial coronariana (DAC). IgA, IgG e IgM específicos para M. pneumoniae foram medidos usando o Anti-M. pneumoniae IgA / IgG / IgM ELISA. A detecção de M. pneumoniae visando o gene de adesão P1 foi realizada por PCR. A infecção aguda por M. pneumoniae foi diagnosticada em 43,3% (42) dos pacientes pela PCR. Os anticorpos específicos para M. pneumoniae foram detectados em 36,1% (35) dos pacientes. Vinte e cinco (25,8%) casos tinham anticorpos IgG, 15 (15,5%) casos tinham anticorpos IgM, 3 (3,1%) casos tinham anticorpos IgA, 10 (10,3%) casos tinham anticorpos IgM + IgG e 1 (1%) caso de cada um tinha anticorpos IgM + IgA e IgG + IgA. Nenhum dos casos foi positivo para os três anticorpos. A análise do coeficiente de correlação de Pearson revelou uma excelente correlação entre o PCR e os resultados sorológicos (r = 0,921, p < 0,001). A maioria (17, 40,5%) dos pacientes positivos para M. pneumoniae está na faixa etária de 41-50 anos, seguida por 10 (23,8%) pacientes na faixa etária de 61-70 anos e 2 (4,8%) pacientes tinham > 70 anos de idade. Nosso estudo relatou uma prevalência incomumente maior de M. pneumoniae por testes sorológicos (36,1%) e PCR (43,3%). Embora a hipótese da associação de M. pneumoniae e DAC ainda não tenha sido comprovada, a prevalência incomumente alta de M. pneumoniae em pacientes com DAC indica uma associação, se não, no desenvolvimento de aterosclerose.

Abstract Coronary heart disease (CHD) has been associated with significant morbidity and mortality worldwide. Although remain controversial, several studies have demonstrated the association of M. pneumoniae infections with atherosclerosis. We evaluated the possible association of mycoplasma infections in patients diagnosed with atherosclerosis by ELISA and PCR methods. Atherosclerotic tissue samples and blood samples were collected for the detection of mycoplasma antibodies (IgA) by ELISA from the 97 patients with coronary artery disease (CAD). M. pneumoniae specific IgA, IgG and IgM were measured by using the Anti-M. pneumoniae IgA/IgG/IgM ELISA. Detection of M. pneumoniae targeting the P1 adhesion gene was performed by PCR Acute infection of M. pneumoniae was diagnosed in 43.3% (42) of patients by PCR. The M. pneumoniae specific antibodies were detected in 36.1% (35) of patients. Twenty-five (25.8%) cases had IgG antibodies, 15 (15.5%) cases had IgM antibodies, 3 (3.1%) cases had IgA antibodies, 10 (10.3%) cases had both IgM + IgG antibodies and 1 (1%) case of each had IgM + IgA and IgG + IgA antibodies. None of the cases was positive for all three antibodies. A Pearson correlation coefficient analysis revealed an excellent correlation between the PCR and the serological results (r=0.921, p<0.001). A majority (17, 40.5%) of the M. pneumoniae positive patients are within the 41-50 years of age group, followed by 10 (23.8%) patients in the age group of 61-70 years and 2 (4.8%) patients were >70 years of age. Our study reported an unusually higher prevalence of M. pneumoniae by serological tests (36.1%) and PCR (43.3%). Although the hypothesis of the association of M. pneumoniae and CAD is yet to be proven, the unusually high prevalence of M. pneumoniae in CAD patients indicates an association, if not, in the development of atherosclerosis.

Colorectal cancer (CRC) is the fourth leading cause of cancer-induced mortality. Histone deacetylase 2 (HDAC2) is involved in prognosis and therapy of CRC. This study aimed to explore novel therapeutic targets for CRC. The alteration of HDAC2 expression in CRC tissues was estimated by qRT-PCR. After lentivirus transfection, HDAC2 knockdown was confirmed by western blot analysis. The effect of HDAC2 knockdown on cell proliferation was then assessed by 3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay. Screened by TargetScan, microRNA (miR)-455 was predicted to bind to 3′UTR of HDAC2 and the prediction was verified by luciferase assay. Finally, cells were transfected, respectively, with miR-455 mimics or miR-455 negative control (miR-NC) and the expression of HDAC2, cell proliferation and apoptosis of transfected cells were respectively evaluated by western blot analysis, MTT assay and flow cytometry. Results showed that the HDAC2 expression was up-regulated in CRC tissues (P<0.05). HDAC2 knockdown significantly decreased cell viability at day 3 (P<0.05), day 4 (P<0.01), and day 5 (P<0.001) after infection. Then, miR-455 was verified to directly target HDAC2, resulting in a significant difference in luciferase activity (P<0.01). Moreover, miR-455 decreased the expression of HDAC2 (P<0.01). miR-455 remarkably decreased cell viability at day 3 (P<0.05), day 4 (P<0.01), and day 5 (P<0.001) after transfection while inducing cell apoptosis (P<0.001). In conclusion, miR-455 inhibited cell proliferation while inducing cell apoptosis by targeting HDAC2 in CRC cells.

ABSTRACT Pseudomembranous colitis (PMC) occurs mainly in adults and is believed to be caused almost exclusively by toxins produced by Clostridium difficile. Colonoscopy found that PMC occurs mainly in the colon, sigmoid colon and rectum in up to 80% ~ 100% of cases. Colonoscopy is simple and fast. It has the significance of making a definite diagnosis and can be used as the main examination method of diagnosis. Reports of children suffering from PMC are rare. Herein, we report a case of PMC in a child. This report has some clinical value for the study of the spectrum of PMC in patients.

RESUMEN La colitis pseudomembranosa (CPM) ocurre principalmente en adultos, y se cree que es causada casi exclusivamente por las toxinas producidas por Clostridium difficile. La colonoscopía encontró que la CPM se produce principalmente en el colon, el colon sigmoideo y el recto, en hasta un 80% ~ 100% de los casos. La colonoscopía es sencilla y rápida. Tiene la importancia de hacer un diagnóstico definitivo, y puede ser utilizada como el método principal de examen para el diagnóstico. Son raros los reportes sobre niños que sufren de CPM. Aquí reportamos un caso de CPM en un niño. Este reporte tiene cierto valor clínico para el estudio del espectro de CPM en los pacientes.