LncRNA FOXD2-AS1 knockdown inhibits the resistance of human osteosarcoma cells to cisplatin by inhibiting miR-143 expression.

OBJECTIVE: The aim of this study was to explore the effect of long non-coding ribonucleic acid (lncRNA) FOXD2-adjacent opposite strand RNA 1 (FOXD2-AS1) on the sensitivity of osteosarcoma cells to cisplatin and its possible underlying mechanism. Our findings might help to provide a certain reference for clinically preventing the drug resistance of osteosarcoma cells. MATERIALS AND METHODS: Cisplatin with a certain concentration gradient was used to induce the stable acquired resistance of human osteosarcoma U2-OS cell line. Subsequently, the expression level of lncRNA FOXD2-AS1 was determined in osteosarcoma cells in non-resistance group (Control group) and Cisplatin-resistance group (Cisplatin-RES group), respectively. Next, the cell line with stable lncRNA FOXD2-AS1 knockdown was constructed in Cisplatin-RES group using small interfering RNA (siRNA). The effects of stable knockdown of lncRNA FOXD2-AS1 on the proliferation of human osteosarcoma cells and the half-maximal inhibitory concentration (IC50) of cisplatin were detected by Cell Counting Kit-8 (CCK-8) assay. 5-ethynyl-2'-deoxyuridine (EdU) staining was performed to measure deoxyribonucleic acid (DNA) replication level in each group of cells. The protein expression levels of apoptosis-associated genes B-cell lymphoma 2 (Bcl-2) and Bcl-2 associated X protein (Bax) in each group of cells were measured via Western blotting. The migration and invasion abilities of cells in each group were determined using wound-healing assay and transwell assay. In addition, the expression of micro RNA (miR)-143 in each group of cells was detected via Reverse Transcription-Polymerase Chain Reaction (RT-PCR). RESULTS: Compared with Control group, the expression level of lncRNA FOXD2-AS1 rose significantly in cells in Cisplatin-RES group (p<0.05). Knockdown of FOXD2-AS1 evidently decreased the IC50 of cisplatin in human osteosarcoma cells (p<0.05). According to EdU staining results, the knockdown of FOXD2-AS1 distinctly inhibited the proliferation of osteosarcoma cells (p<0.05). Western blotting results demonstrated that the knockdown of FOXD2-AS1 remarkably upregulated the expression of pro-apoptotic protein Bax and repressed that of anti-apoptotic protein Bcl-2 in drug-resistant human osteosarcoma cells (p<0.05). Moreover, the knockdown of FOXD2-AS1 significantly weakened the migration and invasion abilities of drug-resistant human osteosarcoma cells (p<0.05). Finally, it was found that the expression level of miR-143 was distinctly elevated in drug-resistant human osteosarcoma cells after knockdown of FOXD2-AS1 (p<0.05). CONCLUSIONS: LncRNA FOXD2-AS1 knockdown inhibits the resistance of human osteosarcoma cells to cisplatin, promotes their apoptosis and weakens their invasion and migration abilities. The possible underlying mechanism may be related to the inhibition of miR-143 expression by lncRNA FOXD2-AS1 in drug-resistant cell lines.

Comparison of interferon-gamma response between tuberculosis and non-tubercular pneumonia.

OBJECTIVE AND DESIGN: Macrophages aided by interferon-gamma (IFN-gamma) are vital to controlling Mycobacterium tuberculosis (M. tuberculosis) infection. Although numerous studies have compared IFN-gamma response between tubercular patients and healthy controls, no studies have investigated IFN-gamma response in patients with pulmonary tuberculosis and non-tubercular pneumonia. The aim of this work was to examine the difference in IFN-gamma response between patients with tuberculosis and non-tubercular pneumonia. METHODS: IFN-gamma production was detected based on the difference in supernatants between non-stimulated and stimulated peripheral blood mononuclear cells by phytohemagglutinin in 83 tubercular patients and 47 patients with pneumonia. Presence of a cavity on chest radiography and co-morbidities of pneumoconiosis, bronchiectasis, liver cirrhosis, renal failure on hemodialysis, diabetes mellitus (DM) and lung cancer were recorded for analysis. RESULTS: Interferon-gamma response, DM and a cavity on chest radiography were independent factors for predicting active pulmonary tuberculosis. Interferon-gamma response was decreased in patients with pulmonary tuberculosis compared with that in patients with non-tubercular pneumonia. Notably, M. tuberculosis infection was the principal factor correlated with IFN-gamma response. CONCLUSION: The IFN-gamma response was principally affected by M. tuberculosis infection and not by other co-morbidities. Further study is required to identify the mechanism of decreased IFN-gamma production.

Risk factors of mortality for nosocomial pneumonia: importance of initial anti-microbial therapy.

Nosocomial pneumonia is a common nosocomial infection and has high mortality rate. Risk factors of mortality of nosocomial pneumonia were studied in 132 hospitalised patients who developed nosocomial pneumonia. The overall mortality rate was 64/132, 48.5%. Of the 11 risk factors univariately associated with mortality due to nosocomial pneumonia, only the inappropriate initial anti-microbial therapy, high simplified acute physiology score and multiple organ failures remained significant after stepwise logistic regression. Gram-negative bacilli were still the most pre-dominant causative microbiologic agents of nosocomial pneumonia with Pseudomonas aeruginosa (20.3%), Acinetobacter baumannii (18.6%) and Escherichia coli (5.9%) being the three most predominant pathogens. A. baumannii were significantly more predominant among non-survivors than survivors (13.56 vs. 5.08%, p=0.0418). The incidence rate of methicillin-resistant Staphylococcus aureus was 19.5% higher than previous reports. We conclude that inappropriate initial anti-microbial therapy for nosocomial pneumonia is associated with the mortality rate of nosocomial pneumonia, and appropriate anti-microbial therapy improves outcome of nosocomial pneumonia.

Proinflammatory cytokines and fibrinolytic enzymes in tuberculous and malignant pleural effusions.

OBJECTIVES: To measure tumor necrosis factor-alpha (TNF-alpha) and interleukin-1beta (IL-1beta) in pleural effusions caused by tuberculosis (TB) and malignancy and their relationship with plasminogen activator inhibitor type I (PAI-1) and tissue type plasminogen activator (tPA), and to compare the differences between tuberculous and malignant pleural effusions. In addition, the relationship between the effusion levels of these parameters and the development of residual pleural thickening was evaluated in the patients with tuberculous pleurisy. DESIGN: Prospective study. MATERIALS AND METHODS: TNF-alpha, IL-1beta, PAI-1, and tPA were measured simultaneously in blood and pleural fluid using an enzyme-linked immunosorbent assay in 33 patients with tuberculous and in 30 patients with malignant pleural effusions. Residual pleural thickening was measured and defined as a pleural thickness of >/= 10 mm found on chest radiographs at the completion of anti-TB chemotherapy in tuberculous pleurisy patients. RESULTS: In both groups, the levels of proinflammatory cytokines and fibrinolytic enzymes were significantly higher in pleural fluid than in blood. The levels of TNF-alpha and PAI-1 were significantly higher in tuberculous than in malignant effusions. In contrast, malignant pleural fluid had significantly higher values of tPA than did tuberculous pleural fluid. In tuberculous effusions, the values of PAI-1 and the PAI-1/tPA ratio correlated positively and the levels of tPA correlated negatively with those of TNF-alpha and IL-1beta. In malignant pleural fluid, positive correlations were found between the values of proinflammatory cytokines (TNF-alpha and IL-1beta) and PAI-1. Residual pleural thickening was found in 9 of 33 patients (27. 3%) with tuberculous pleurisy. The pleural fluid values of TNF-alpha, IL-1beta, and PAI-1 were significantly higher and the concentrations of tPA were significantly lower in tuberculous pleurisy patients with residual pleural thickening. CONCLUSIONS: Compared to malignant pleural effusion, fibrinolytic activity in pleural fluid was reduced in tuberculous effusion. Pleural inflammation caused by TB may enhance the release of proinflammatory cytokines, particularly TNF-alpha, which subsequently may increase PAI-1 and decrease tPA in pleural fluid. The imbalance of PAI-1 and tPA in pleural space may lead to fibrin deposition and pleural thickening.

Prognostic value of dobutamine echocardiography in patients after Q-wave or non-Q-wave acute myocardial infarction.

We investigated the role of dobutamine echocardiography in predicting future spontaneous events in patients with Q-wave or non-Q-wave first acute myocardial infarction (AMI). DE was performed in 168 patients with a Q-wave AMI and 105 patients with a non-Q-wave AMI. Patients were observed for hard events (cardiac death and nonfatal reinfarction) and all spontaneous events (hard events and unstable angina). When compared to patients with a Q-wave AMI, patients with non-Q-wave AMI had a higher rate of positive dobutamine echocardiographic results (51.8% vs 80.0%, p <0.0001), greater changes in wall motion score index (WMSI) (0.31+/-0.17 vs 0.42+/-0.23, p = 0.001), and more remote zone ischemia (27.9% vs 43.8%, p = 0.0072). Patients with non-Q-wave infarct had a higher all-event rate, but a similar hard-event rate. In patients with a positive dobutamine echocardiogram (DE), the rate of hard or all events was similar, regardless of different infarct patterns. Patients with a negative DE had a higher event-free survival rate for all events in both Q-wave (85.2% vs 60.9%, p <0.0001) and non-Q-wave (76.2% vs 52.4%, p = 0.0083) groups. By stepwise analysis in the Q-wave group, the most important predictors were peak stress WMSI and diabetes for hard events, and a positive DE and baseline WMSI for all events. However, in the non-Q-wave group, the strongest predictors were dobutamine time for hard events and positive DE for all events. We conclude that a positive DE is a powerful predictor of future spontaneous events in patients after either a Q-wave or non-Q-wave AMI. However, for hard events, high-risk patients with different infarct patterns were recognized with variable efficiency by different dobutamine echocardiographic variables.

Antituberculosis drug resistance in Keelung area-1993 to 1994.

Patterns of drug resistance of 176 isolates of Mycobacterium tuberculosis collected from 1993 to 1994 were reviewed retrospectively. The rates of resistance to isoniazid, rifampicin, ethambutol and streptomycin were 84.1%, 17.6%, 23.3% and 11.9% respectively and the incidence of multidrug-resistant M. tuberculosis was 17.0%. Comparisons between 1993 and 1994 showed decrease in rates of resistance to rifampicin (25% vs. 7.5%) and ethambutol (36.5% vs. 7.5%) and the incidence of multidrug-resistant tuberculosis (25% vs. 7.5%). In contrast, the rate of resistance to isoniazid increased from 79.2% to 84.1%. Due to the high frequency of resistance to multiple drugs in tuberculosis isolates at Chang Gung Memorial Hospital, Keelung, three-combined (isoniazid+rifampicin+ethambutol) regimen of antituberculosis drugs may be ineffective as initial therapy for one-fourth of patients in our hospital. Of epidemiological factors, previous treatment was found to influence the rates of drug resistance. Of roentgenographic features, stage of chest roentgenography was found to be a positive predictor of infection with multidrug-resistant tuberculosis. The information provided in this study may help us understanding the epidemiology of M. tuberculosis in Keelung and refining antituberculosis treatment for our patients.