ABSTRACT
Acanthamoeba spp. are opportunistic human pathogens that cause granulomatous amoebic encephalitis and keratitis, and their accurate detection and enumeration in environmental samples is a challenge. In addition, information regarding the genotyping of Acanthamoeba spp. using various PCR methods is equally critical. Therefore, considering the diverse niches of habitats, it is necessary to develop an even more efficient genotyping method for Acanthamoeba spp. detection. This study improved the sensitivity of detection to avoid underestimation of Acanthamoeba spp. occurrence in aquatic environmental samples, and to accurately define the pathogenic risk by developing an efficient PCR method. In this study, a new nested genotyping method was established and compared with various PCR-based methods using in silico, lab, and empirical tests. The in silico test showed that many PCR-based methods could not successfully align specific genotypes of Acanthamoeba, except for the newly designed nested PCR and real-time PCR method. Furthermore, 52 water samples from rivers, reservoirs, and a river basin in Taiwan were analysed by six different PCR methods and compared for genotyping and detection efficiency of Acanthamoeba. The newly developed nested-PCR-based method of genotyping was found to be significantly sensitive as it could effectively detect the occurrence of Acanthamoeba spp., which was underestimated by the JDP-PCR method. Additionally, the present results are consistent with previous studies indicating that the high prevalence of Acanthamoeba in the aquatic environment of Taiwan is attributed to the commonly found T4 genotype. Ultimately, we report the development of a small volume procedure, which is a combination of recent genotyping PCR and conventional real-time PCR for enumeration of aquatic Acanthamoeba and acquirement of biologically meaningful genotyping information. We anticipate that the newly developed detection method will contribute to the precise estimation, evaluation, and reduction of the contamination risk of pathogenic Acanthamoeba spp., which is regularly found in the water resources utilised for domestic purposes.
Subject(s)
Acanthamoeba/isolation & purification , Environmental Monitoring/methods , Genotyping Techniques , Polymerase Chain Reaction/methods , Rivers/parasitology , Acanthamoeba/geneticsABSTRACT
Methicillin-resistant Staphylococcus aureus (MRSA) is a major threat to public health that causes infections in hospitals, communities, and animal husbandry. Livestock-associated MRSA (LA-MRSA) is defined as MRSA possessing staphylococcal cassette chromosome mec (SCCmec) IV or V, both of which lacks the Panton-Valentine leukocidin (PVL) gene but has variable combinations of antimicrobial susceptibility. This study focused on Taiwan's subtropical river basin and the Puzih River, which converges from tributaries flowing through downtown and animal husbandry areas. MRSA was detected at a rate of 7.8% in the tributaries, which was higher than downstream (2.1%). The ratio of multidrug-resistant (MDR) MRSA (n = 30) to total MRSA isolates (n = 39) was 0.769, and most of the MDR MRSA isolates (66.7%, 20/30) exhibited resistance to chloramphenicol, ciprofloxacin, clindamycin, erythromycin, sulfamethoxazole-trimethoprim, and tetracycline. The number of MDR MRSA isolates in the tributaries was also higher than the downstream regions of the Puzih River. The majority of MRSA isolates (64.1%) observed in this study possessed SCCmec type IV without PVL, which is typical for LA-MRSA. Enterobacterial repetitive intergenic consensus PCR (ERIC-PCR) typing aided the discrimination of resistance patterns among SCCmec types. This study highlights the threat to human health posed by the waterborne transmission of MDR LA-MRSA.
Subject(s)
Drug Resistance, Multiple, Bacterial , Methicillin-Resistant Staphylococcus aureus/drug effects , Rivers/microbiology , Water Pollution , Animal Husbandry , Animals , Livestock , Methicillin-Resistant Staphylococcus aureus/isolation & purification , TaiwanABSTRACT
Uremic toxins are considered a risk factor for cardiovascular disorders in kidney diseases, but it is not known whether, under inflammatory conditions, they affect adhesion molecule expression on endothelial cells, which may play a critical role in acute kidney injury (AKI). In the present study, in cardiovascular surgery-related AKI patients, who are known to have high plasma levels of the uremic toxin indoxyl sulfate (IS), plasma levels of IL-1ß were found to be positively correlated with plasma levels of the adhesion molecule E-selectin. In addition, high E-selectin and IL-1ß expression were seen in the kidney of ischemia/reperfusion mice in vivo. We also examined the effects of IS on E-selectin expression by IL-1ß-treated human umbilical vein endothelial cells (HUVECs) and the underlying mechanism. IS pretreatment of HUVECs significantly increased IL-1ß-induced E-selectin expression, monocyte adhesion, and the phosphorylation of mitogen-activated protein kinases (ERK, p38, and JNK) and transcription factors (NF-κB and AP-1), and phosphorylation was decreased by pretreatment with inhibitors of ERK1/2 (PD98059), p38 MAPK (SB202190), and JNK (SP600125). Furthermore, IS increased IL-1ß-induced reactive oxygen species (ROS) production and this effect was inhibited by pretreatment with N-acetylcysteine (a ROS scavenger) or apocynin (a NADPH oxidase inhibitor). Gel shift assays and ChIP-PCR demonstrated that IS enhanced E-selectin expression in IL-1-treated HUVECs by increasing NF-κB and AP-1 DNA-binding activities. Moreover, IS-enhanced E-selectin expression in IL-1ß-treated HUVECs was inhibited by Bay11-7082, a NF-κB inhibitor. Thus, IS may play an important role in the development of cardiovascular disorders in kidney diseases during inflammation by increasing endothelial expression of E-selectin.
Subject(s)
E-Selectin/metabolism , Endothelium, Vascular/drug effects , Indican/toxicity , Interleukin-1beta/agonists , MAP Kinase Signaling System/drug effects , Poisons/toxicity , Up-Regulation/drug effects , Acute Kidney Injury/blood , Acute Kidney Injury/metabolism , Acute Kidney Injury/pathology , Acute Kidney Injury/physiopathology , Aged , Animals , Biomarkers/blood , Biomarkers/metabolism , Cells, Cultured , Disease Models, Animal , E-Selectin/chemistry , E-Selectin/genetics , Endothelium, Vascular/metabolism , Endothelium, Vascular/pathology , Endothelium, Vascular/physiopathology , Female , Human Umbilical Vein Endothelial Cells , Humans , Indican/blood , Interleukin-1beta/metabolism , Kidney/blood supply , Kidney/metabolism , Kidney/pathology , Kidney/physiopathology , Male , Mice, Inbred C57BL , Oxidative Stress/drug effects , Poisons/blood , Reperfusion Injury/blood , Reperfusion Injury/metabolism , Reperfusion Injury/pathology , Reperfusion Injury/physiopathology , Uremia/etiologyABSTRACT
Ischemia-reperfusion (I/R) injury to the kidney, a major cause of acute renal failure in humans, is associated with a high mortality, and the development of a new therapeutic strategy is therefore highly desirable. In this study, we examined the therapeutic potential of implantation of endothelial progenitor cells (EPCs) isolated from Wharton's jelly of human umbilical cords in the treatment of renal I/R injury in mice. To visualize the localization of the transplanted EPCs, the cells were labeled with Q-tracker before injection into the renal capsule. Mice with renal I/R injury showed a significant increase in blood urea nitrogen and creatinine levels, and these effects were decreased by EPC transplantation. The kidney injury score in the mice with I/R injury was also significantly decreased by EPC transplantation. EPC transplantation increased the microvascular density, and some of the EPCs surrounded and were incorporated into microvessels. In addition, EPC transplantation inhibited the I/R-induced cell apoptosis of endothelial, glomerular, and renal tubular cells, as demonstrated by TUNEL staining, and significantly reduced reactive oxygen species production and the expression of the inflammatory chemokines macrophage inflammatory protein-2 and keratinocyte-derived cytokine, as shown by immunostaining and ELISA. Moreover, EPC transplantation reduced I/R-induced fibrosis, as demonstrated by immunostaining for S100A4, a fibroblast marker, and by Jones silver staining. To our knowledge, this is the first report that transplantation of EPCs from Wharton's jelly of human umbilical cords might provide a novel therapy for ischemic acute kidney injury by promoting angiogenesis and inhibiting apoptosis, inflammation, and fibrosis.
Subject(s)
Acute Kidney Injury/therapy , Endothelial Progenitor Cells/metabolism , Reperfusion Injury/therapy , Umbilical Cord/metabolism , Wharton Jelly/metabolism , Animals , Apoptosis , Fibrosis/metabolism , Humans , Inflammation/metabolism , MiceABSTRACT
The expression of inflammatory cytokines on vascular walls is a critical event in vascular diseases and inflammation. The aim of the present study was to examine the effects of an extract of Ganoderma lucidum (Reishi) polysaccharides (EORPs), which is effective against immunological disorders, on interleukin- (IL-) 1 ß expression by human aortic smooth muscle cells (HASMCs) and the underlying mechanism. The lipopolysaccharide- (LPS-) induced IL-1 ß expression was significantly reduced when HASMCs were pretreated with EORP by Western blot and immunofluorescent staining. Pretreatment with 10 µ g/mL EORP decreased LPS-induced ERK, p38, JNK, and Akt phosphorylation. But the increase in IL-1 ß expression with LPS treatment was only inhibited by pretreatment with the ERK1/2 inhibitor, while the JNK and p38 inhibitors had no effect. In addition, EORP reduced the phosphorylation and nuclear translocation of nuclear factor- (NF-) κ B p65 in LPS-treated HASMCs. Furthermore, in vivo, IL-1 ß expression was strongly expressed in thoracic aortas in LPS-treated mice. Oral administration of EORP decreased IL-1 ß expression. The level of IL-1 ß expression in LPS-treated or in LPS/EORP-treated group was very low and was similar to that of the saline-treated group in toll-like receptor 4-deficient (TLR4(-/-)) mice. These findings suggest that EORP has the anti-inflammatory property and could prove useful in the prevention of vascular diseases and inflammatory responses.
ABSTRACT
Ganoderma lucidum is used in traditional Chinese medicine to prevent or treat a variety of diseases, including cardiovascular disorders. We previously demonstrated that a glucan-containing extract of Reishi polysaccharides (EORP) has the potent anti-inflammatory action of reducing ICAM-1 expression in lipopolysaccharide (LPS)-treated human aortic smooth muscle cells (HASMCs) and LPS-treated mice. In the present study, we examined whether EORP inhibited platelet-derived growth factor-BB (PDGF)-stimulated HASMC proliferation and the mechanism involved. EORP dose-dependently reduced cell numbers and DNA synthesis of PDGF-treated HASMCs in vitro. EORP also arrested cell cycle progression in the G0/G1 phase, and this was associated with decreased expression of cyclin D1, cyclin E, CDK2, CDK4, and p21(Cip1) and upregulation of the cyclin-dependent kinase inhibitor p27(Kip1). The anti-proliferative effect of EORP was partly mediated by downregulation of PDGF-induced JNK phosphorylation. In in vivo studies, the femoral artery of C57BL/6 mice was endothelial-denuded and the mice were fed a diet containing 100 mg/kg/day of EORP. On day 14, both cell proliferation (proliferating cell nuclear antigen-positive cells) in the neointima and the neointima/media area ratio (0.67 ± 0.03 vs. 1.46 ± 0.30) were significantly reduced. Our data show that EORP interferes with the mitogenic activation of JNK, preventing entry of HASMCs into the cell cycle in vitro and reducing cell proliferation in the neointima and decreasing the neointimal area in vivo. Thus, EORP may represent a safe and effective novel approach to the prevention and treatment of vascular proliferative diseases.