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Diarrheagenic Escherichia coli (DEC) are the most common agents of diarrhea. Waterborne DEC could pose a potential health risk to human through agricultural, household, recreational, and industrial use. There are few published reports on the detection of DEC and its seasonal distribution in aquatic environments. The presence of DEC in different types of aquatic environments was investigated in this study. Water samples were collected from major rivers, water reservoirs, and recreational hot springs throughout Taiwan. Moreover, an intensive water sampling plan was carried out along Puzih River. The detection of DEC target genes was used to determine the presence of enterotoxigenic E. coli (ETEC), enteropathogenic E. coli (EPEC), and Shiga toxin-producing E. coli (STEC). Among the 383 water samples analyzed, DEC was found in 122 (31.8%) samples. The detection rate varied by genotype, raging from 3.6% for STEC to 17.2% for EPEC. The DEC detection rate was higher from river waters than reservoirs and hot springs. In addition, DEC was detected at a higher rate in spring and summer. The presence of EPEC was significantly associated with total coliform levels among hot spring samples. Moreover, the presence of ETEC in river water samples was associated with heterotrophic plate counts. Water with EPEC differed significantly in pH from Puzih River samples. These results suggest that seasonal characteristics may affect the presence of DEC in different aquatic environments, and water quality indicators may be indicative of the presence of DEC., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Free-living amoebae (FLA) are ubiquitous in various aquatic environments. Several amoebae species are pathogenic and host other pathogens such as Legionella, but the presence of FLA and its parasites as well as the related infection risk are not well known. In this study, the presence of pathogenic FLA and Legionella in various water bodies was investigated. Water samples were collected from a river, intake areas of drinking water treatment plants, and recreational hot spring complexes in central and southern Taiwan. A total of 140 water samples were tested for the presence of Acanthamoeba spp., Naegleria spp., Vermamoeba vermiformis, and Legionella. In addition, phylogenetic characteristics and water quality parameters were also assessed. The pathogenic genotypes of FLA included Acanthamoeba T4 and Naegleria australiensis, and both were abundant in the hot spring water. In contrast, Legionella pneumophila was detected in different aquatic environments. Among the FLA assessed, V. vermiformis was most likely to coexist with Legionella spp. The total bacteria level was associated with the presence of FLA and Legionella especially in hot spring water. Taken together, FLA contamination in recreational hot springs and drinking water source warrants more attention on potential legionellosis and amoebae infections., (Copyright © 2014. Published by Elsevier B.V.)

Antibiotics are widely used in livestock for infection treatment and growth promotion. Wastes from animal husbandry are a potential environmental source of antibiotic-insensitive pathogens, and the removal efficiency of the resistance genotypes in current wastewater treatment plants (WWTPs) is unknown. In this study, quantitative PCR was used for evaluating antibiotic resistance genes in wastewater treatment processes. Six wastewater treatment plants in different swine farms were included in this study, and five antibiotic resistance genes (ARGs) were tested for each treatment procedure. All of the tested ARGs including tetA, tetW, sulI, sulII, and blaTEM genes were detected in six swine farms with considerable amounts. The results showed that antibiotic resistance is prevalent in livestock farming. The ARG levels were varied by wastewater treatment procedure, frequently with the highest level at anaerobic treatment tank and lowest in the activated sludge unit and the effluents. After normalizing the ARG levels to 16S rRNA gene copies, the results showed that ARGs in WWTP units fluctuated partly with the quantity of bacteria. Regardless of its importance in biodegradation, the anaerobic procedure may facilitate bacterial growth thus increasing the sustainability of the antibiotic resistance genotypes. After comparing the copy numbers in influx and efflux samples, the mean removal efficiency of ARGs ranged between 33.30 and 97.56%. The results suggested that treatments in the WWTP could partially reduce the spread of antibiotic-resistant bacteria, and additional procedures such as sedimentation may not critically affect the removal efficiency., (Copyright © 2014 Elsevier B.V. All rights reserved.)

In this study, TaqMan fluorescent quantitative real-time PCR was performed to quantify Legionella species in reservoirs. Water samples were collected from 19 main reservoirs in Taiwan, and 12 (63.2%) were found to contain Legionella spp. The identified species included uncultured Legionella spp., L. pneumophila, L. jordanis, and L. drancourtii. The concentrations of Legionella spp. and L. pneumophila in the water samples were in the range of 1.8×10(2)-2.6×10(3) and 1.6×10(2)-2.4×10(2) cells/L, respectively. The presence and absence of Legionella spp. in the reservoir differed significantly in pH values. These results highlight the importance that L. pneumophila, L. jordanis, and L. drancourtii are potential pathogens in the reservoirs. The presence of L. pneumophila in reservoirs may be a potential public health concern that must be further examined., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Background Aims: We investigated bone marrow stromal cell (BMSC) transplantation combined with angiotensin-converting enzyme inhibitor (ACEI) treatment in acute myocardial infarction (AMI) and the role of insulin-like growth factor-1 (IGF-1)., Methods: AMI models were established in Sprague-Dawley rats by ligation of the left anterior descending coronary artery and grouped into blank control (BC), ACEI treatment (ACEI), BMSC transplantation (BMSC) and BMSC transplantation plus ACEI (combined). Perindopril (2.5 mg/kg) was administered by gavage to ACEI and combined groups from the day after AMI. BMSC (2 × 10(8)) were injected into the border of the MI area a week later in the BMSC and combined groups., Results: After 4 weeks, hemodynamics in the BMSC and combined groups were significantly improved (P < 0.05 versus BC), with the greatest improvement in the combined group (P < 0.05). In addition, an increased number of BMSC survived in the combined group (P < 0.05 versus BMSC). A proportion of BMSC was positive for troponin T, as detected by immunofluorescence. The number of apoptotic cardiomyocytes was decreased in the BMSC and ACEI groups, and even further in the combined group (P < 0.05). IGF-1 expression was up-regulated in the BMSC and combined groups (P < 0.05 versus BC), but not in the ACEI group. B cell lymphoma-2 (Bcl-2) expression was up-regulated in the ACEI, BMSC and combined groups, with the highest expression in the combined group (P < 0.05)., Conclusions: Our results show that BMSC engrafted in AMI can survive well and secrete IGF-1 and preserve cardiac function significantly. These data suggest that BMSC transplantation inhibits apoptosis of cardiomyocytes by up-regulation of Bcl-2 expression in the myocardium, and this effect might be sensitized by ACEI.