[MiR-183 Regulates Proliferation of SW1990 Pancreatic Cancer Cell Line by Targeting PDCD4].

OBJECTIVES: To investigate the effect of miR-183 on the cell proliferation in SW1990 pancreatic cancer cell line by targeting programmed cell death factor 4(PDCD4). METHODS: The SW1990 pancreatic cancer cells were transfected with miR-183 mimics and inhibitors at different concentrations, the alteration of PDCD4 levels was observed at specific concentrations by qPCR and Western blot. The cellular proliferation of transfected cells was determined by MTT assay. The distribution of cell cycle and apoptosis was examined by flow cytometry (FCM) and Hoechst 33258 staining. The expression of B-cell lymphoma(bcl-2) was evaluated by Western blot. RESULTS: The miR-183 mimic and inhibitor (at concentrations of 50 nmol/L or 150 nmol/L) showed significantly increasing or decreasing effects on the levels ofmiR-183 respectively. The expression of PDCD4 was downregulated in the cells transfected with miR-183 mimics, while significantly upregulated in the cells treated with miR-183 inhibitors. Western blot showed that miR-183 inhibitors resulted in a marked decrease in the expression levels of bcl-2. The growth of SW1990 cells was obviously inhibited after anti-miR-183 treatment, while an increase of apoptosis cells proportion and cell cycle G0/G1 arrest were observed after miR-183 inhibitors transfection. CONCLUSIONS: The miR-183 inhibitors could restrain cell proliferation, promote cell apoptosis and increase G0/G1 arrest in SW1990 pancreatic cancer cells, which may be possibly through targeting PDCD4.

Investigation of a cluster of Legionnaires' disease during the outbreak of coronavirus disease 2019 pandemic in northeastern Taiwan, June 2021.

PURPOSE: To describe the investigation and intervention of a cluster of Legionnaires' disease detected during the outbreak of coronavirus disease 2019 (COVID-19) pandemic. METHODS: From June 7 to 22, 2021, 15 cases in the neighborhood near our hospital were detected. Information about residence, workplace, hospital visit, and potential exposures was collected. Sampling and decontamination were performed for potential sources. RESULTS: All 15 patients had pneumonia when visiting the emergency room with negative COVID-19 test results. Most patients were male (73.3%) with the mean age of 65.7 years. The most common comorbidities were diabetes mellitus (40.0%) and hypertension (40%). The most common symptom was fever (93.3%). Two (13.3%) patients needed mechanical ventilators. Fever subsided within 2 days of treatment for most cases (85.7%). Five cases had exposure history at our hospital, and the other 10 lived or worked in the area within 2 km of our hospital, mostly in buildings A and B. Water sampling was carried out for our hospital, buildings A and B; one water sample from a cooling tower in our hospital cultured positive for Legionella bacteria. Early testing and treatment for suspected cases were carried out for the outbreak, and all cases were discharged with pneumonia resolution. CONCLUSION: This was a community outbreak of Legionnaires' disease near our hospital. COVID-19 tests were repeated frequently before testing for Legionnaires' disease during the COVID-19 pandemic. Early recognition of Legionnaires' disease and timely treatment improved outcome.

Changes in interferon-γ release assay readout after COVID-19 vaccination: A prospective cohort study.

OBJECTIVES: Interferon-γ release assays (IGRAs) are widely used in public health practice to diagnose latent tuberculosis. During the COVID-19 pandemic and rollout of COVID-19 vaccination, it has remained unclear whether COVID-19 vaccines interfere with IGRA readouts. METHODS: We prospectively recruited healthcare workers during their annual occupational health examinations in 2021. Baseline IGRA readouts were compared with follow-up data after the participants had received two doses of COVID-19 vaccination. RESULTS: A total of 134 baseline IGRA-negative cases (92 with ChAdOx1 vaccine, 27 with mRNA-1273 vaccine, and 15 with heterologous vaccination) and seven baseline IGRA-positive cases were analyzed. Among the baseline IGRA-negative cases, there were decreased interferon-γ concentrations over the Nil (P = 0.005) and increased Mitogen-Nil (P < 0.001) values after vaccination. For TB2-Nil value, a similar trend (P = 0.057) of increase was observed. Compared with the 0.35 IU/ml threshold, the baseline and follow-up readout differences were less than |± 0.10| IU/ml over the TB1-Nil and TB2-Nil values in >90% baseline IGRA-negative cases. No significant readout difference was observed among baseline IGRA-positive cases. CONCLUSION: COVID-19 vaccination did not change IGRA interpretation in most cases. Cases showing conversion/borderline IGRA readouts should be given special consideration.

The emergence of Clostridioides difficile PCR ribotype 127 at a hospital in northeastern Taiwan.

BACKGROUND: Several studies have highlighted the incidence of Clostridioides difficile infections (CDIs) in Taiwan and certain ribotypes have been related to severe clinical diseases. A study was conducted to investigate the polymerase chain reaction (PCR) ribotypes and genetic relatedness of clinical C. difficile strains collected from January 2009 to December 2015 at a hospital in northeastern Taiwan. MATERIAL AND METHODS: A modified two-step typing algorithm for C. difficile was used by combining a modified 8-plex and 3'-truncated tcdA screening PCR. In addition, MLVA typing was adopted for investigation of bacterial clonality and transmission. RESULTS: Among a total of 86 strains, 24 (28%) were nontoxigenic and 62 (72%) had both tcdA and tcdB (A + B+). No tcdA-negative and tcdB-positive (A-B+) strains were identified. Binary toxin (CDT)-producing (cdtA+/cdtB+) strains were started to be identified in 2013. The 21 (34%) A+B+ clinical strains with binary toxin and tcdC deletion were identified as RT127 strains, which contained both RT078-lineage markers and fluoroquinolone (FQ)-resistant mutations (Thr82Ile in gyrA). Multiple loci variable-number tandem repeat analysis (MLVA) for phylogenetic relatedness of RT127 strains indicated that 20 of 21 strains belonged to a clonal complex that was identical to a clinical strain collected from southern Taiwan in 2011, suggestive of a clonal expansion in Taiwan. CONCLUSION: A two-step typing method could rapidly confirm species identification and define the toxin gene profile of C. difficile isolates. The clonal expansion of RT127 strains in Taiwan indicates monitoring and surveillance of toxigenic C. difficile isolates from human, animal, and environment are critical to develop One Health prevention strategies.

Colistin for pneumonia involving multidrug-resistant Acinetobacter calcoaceticus-Acinetobacter baumannii complex.

OBJECTIVES: To investigate clinical and microbiological response, and 30-day mortality of pneumonia involving multidrug-resistant (MDR) Acinetobacter calcoaceticus-Acinetobacter baumannii (Acb) complex treated with colistin, and identify associated factors of these outcomes. METHODS: A retrospective study of 183 adult patients with colistin treatment for at least 7 days between January 2014 and October 2017. RESULTS: The mean age was 76.8 years, and mean Acute Physiology and Chronic Health Evaluation II score was 17.7. Eighteen (9.8%) and 128 (69.9%) patients had intravenous (IV) colistin alone and inhaled (IH) colistin alone, respectively. Thirty-seven patients had both IV and IH colistin, including 5 (2.7%) with concurrent, and 32 (17.5%) with non-concurrent use of IV and IH colistin. The 30-day mortality rate was 19.1% and 131 (71.6%) patients had clinical response. In the 175 patients with available data, 126 (72%) had microbiological eradication. The multivariate analyses revealed that IH colistin alone was an independent predictor for 30-day survival, clinical response, and microbiological eradication, and IV colistin alone was an independent predictor for clinical failure. Patients with IV colistin alone had a significantly higher nephrotoxicity rate than IH colistin alone (37.5% vs 6.1%, P = 0.001). Sub-group analysis of 52 patients with IV colistin for ≧ 4 days revealed that 14 (26.9%) patients had inappropriate dose, and inappropriate dose was an independent predictor for 30-day mortality. CONCLUSIONS: IH colistin provided good outcomes with few side effects, and appropriate dosing of IV colistin was important to avoid excess mortality.

[The relationship between the effects of MTA on mRNA expression of four iconic proteins in cells of fetal rat skull and cell culture environment].

PURPOSE: To discuss the influence of MTA on mRNA expression of Cbfa1, ALP, Col-Ⅰand BGP which are 4 kinds of iconic protein in cells of fetal rats skull, and explore its influence on cell culture environment and association of changes of calcium, phosphorus. METHODS: Cells were obtained by 2 kinds of mixed enzymatic digestion for 3 steps from gestation fetal rat calvarial bone. The expression of Cbfa1mRNA, ALPmRNA, Col-1mRNA, BGP mRNA and extracellular calcium were detected. Phosphorus (P) and calcium concentration of fetal rat skull cells co-cultured with MTA for 3 weeks at different stages of cell differentiation was assessed atomic absorption spectrophotometry. The data was statistically analyzed using SPSS10.0 software package. RESULTS: At the 4th day, P3- content decreased significantly (P<0.05), while ALPmRNA in MTA group increased most greatly and was 40 times of the control group. At the 14th to 18th day, the Ca2+ and P3- content reduced significantly (P<0.05), and then the BGPmRNA in MTA group rised most greatly which was about 7.71 times of the control group. Then Cbfalpha l mRNA in MTA group increased most strongly later which was about 7.38 times of the control group. Col Ⅰ mRNA increased minimally in all time points. CONCLUSIONS: The change of P3- content may be the initiating factor when MTA promoted differentiation of fetal rats skull cells in vitro, and Ca2+ could greatly accelerate the process of mineralization when accumulated to a certain extent. At the same time, the expression of ALPmRNA, BGPmRNA, Col Ⅰ mRNA and Cbfalpha lmRNA were regulated accordingly, which is the key to explain osteogenetic mechanism of MTA.

miR-183 induces cell proliferation, migration, and invasion by regulating PDCD4 expression in the SW1990 pancreatic cancer cell line.

The aim of this study was to investigate the function of miR-183 in the SW1990 cancer cell line, and the mechanisms regulating these processes. miRNAs are known to play important roles in cancer cell development. However, the pattern and biological role of miR-183 in pancreatic cancer remain largely unknown. Here, we have reported the reduction in pancreatic cancer cell growth in vitro by miR-183 intervention, by inducing apoptosis and decreasing the Bcl-2 expression. Moreover, miR-183 was observed to enhance pancreatic cancer cell migration and invasion, whereas inhibition of miR-183 caused an opposite effect. miR-183 inhibition was shown to increase E-cadherin expression and decrease N-cadherin expression. These regulatory actions play an important role in the cancer epithelial-mesenchymal transition (EMT). Mechanistically, we demonstrated that the overexpression of miR-183 decreased the expression of PDCD4 (programmed cell death 4) mRNA and protein, and vice versa. This helped to identify PDCD4 as the target genes in pancreatic cancer. In conclusion, our analyses indicated miR-183 to be an important contributor to cell migration. This could also be used as a potential therapeutic target for pancreatic cancer treatment.