Visual light flicker stimulation: enhancing alertness in sleep-deprived rats.

Introduction: In the evolving field of neurophysiological research, visual light flicker stimulation is recognized as a promising non-invasive intervention for cognitive enhancement, particularly in sleep-deprived conditions. Methods: This study explored the effects of specific flicker frequencies (40 Hz and 20-30 Hz random flicker) on alertness recovery in sleep-deprived rats. We employed a multidisciplinary approach that included behavioral assessments with the Y-maze, in vivo electrophysiological recordings, and molecular analyses such as c-FOS immunohistochemistry and hormone level measurements. Results: Both 40 Hz and 20-30 Hz flicker significantly enhanced behavioral performance in the Y-maze test, suggesting an improvement in alertness. Neurophysiological data indicated activation of neural circuits in key brain areas like the thalamus and hippocampus. Additionally, flicker exposure normalized cortisol and serotonin levels, essential for stress response and mood regulation. Notably, increased c-FOS expression in brain regions related to alertness and cognitive functions suggested heightened neural activity. Discussion: These findings underscore the potential of light flicker stimulation not only to mitigate the effects of sleep deprivation but also to enhance cognitive functions. The results pave the way for future translational research into light-based therapies in human subjects, with possible implications for occupational health and cognitive ergonomics.

Aerobic exercise-induced HIF-1α upregulation in heart failure: exploring potential impacts on MCT1 and MPC1 regulation.

BACKGROUND: The terminal stage of ischemic heart disease develops into heart failure (HF), which is characterized by hypoxia and metabolic disturbances in cardiomyocytes. The hypoxic failing heart triggers hypoxia-inducible factor-1α (HIF-1α) actions in the cells sensitized to hypoxia and induces metabolic adaptation by accumulating HIF-1α. Furthermore, soluble monocarboxylic acid transporter protein 1 (MCT1) and mitochondrial pyruvate carrier 1 (MPC1), as key nodes of metabolic adaptation, affect metabolic homeostasis in the failing rat heart. Aerobic exercise training has been reported to retard the progression of HF due to enhancing HIF-1α levels as well as MCT1 expressions, whereas the effects of exercise on MCT1 and MPC1 in HF (hypoxia) remain elusive. This research aimed to investigate the action of exercise associated with MCT1 and MPC1 on HF under hypoxia. METHODS: The experimental rat models are composed of four study groups: sham stented (SHAM), HF sedentary (HF), HF short-term exercise trained (HF-E1), HF long-term exercise trained (HF-E2). HF was initiated via left anterior descending coronary artery ligation, the effects of exercise on the progression of HF were analyzed by ventricular ultrasound (ejection fraction, fractional shortening) and histological staining. The regulatory effects of HIF-1α on cell growth, MCT1 and MPC1 protein expression in hypoxic H9c2 cells were evaluated by HIF-1α activatort/inhibitor treatment and plasmid transfection. RESULTS: Our results indicate the presence of severe pathological remodelling (as evidenced by deep myocardial fibrosis, increased infarct size and abnormal hypertrophy of the myocardium, etc.) and reduced cardiac function in the failing hearts of rats in the HF group compared to the SHAM group. Treadmill exercise training ameliorated myocardial infarction (MI)-induced cardiac pathological remodelling and enhanced cardiac function in HF exercise group rats, and significantly increased the expression of HIF-1α (p < 0.05), MCT1 (p < 0.01) and MPC1 (p < 0.05) proteins compared to HF group rats. Moreover, pharmacological inhibition of HIF-1α in hypoxic H9c2 cells dramatically downregulated MCT1 and MPC1 protein expression. This phenomenon is consistent with knockdown of HIF-1α at the gene level. CONCLUSION: The findings propose that long-term aerobic exercise training, as a non- pharmacological treatment, is efficient enough to debilitate the disease process, improve the pathological phenotype, and reinstate cardiac function in HF rats. This benefit is most likely due to activation of myocardial HIF-1α and upregulation of MCT1 and MPC1.

Mitochondrial dysfunction of peripheral blood mononuclear cells is associated with lung carcinogenesis.

The composition, quantity, and function of peripheral blood mononuclear cells (PBMCs) are closely correlated with tumorigenesis. However, the mechanisms of PBMCs in lung cancer are not clear. Mitochondria are energy factories of cells, and almost all cellular functions rely on their energy metabolism level. The present study aimed to test whether the mitochondrial function of PBMCs directly determines their tumor immune monitoring function. We recruited 211 subjects, including 105 healthy controls and 106 patients with recently diagnosed with lung cancer. The model of lung carcinogenesis induced by BaP was used in animal experiment, and the Bap carcinogenic metabolite, Benzo(a)pyren-7,8-dihydrodiol-9,10-epoxide (BPDE), was used in cell experiment. We found that mitochondrial function of PBMCs decreased significantly in patients with new lung cancer, regardless of age. In vivo, BaP caused PBMC mitochondrial dysfunction in mice before the appearance of visible malignant tissue. Moreover, mitochondrial function decreased significantly in mice with lung cancers induced by BaP compared to those without lung cancer after BaP intervention. In vitro, BPDE also induced mitochondrial dysfunction and reduced the aggressiveness of PBMCs toward cancer cells. Furthermore, the changes in mitochondrial energy metabolism gene expression caused by BPDE are involved in this process. Thus, the mitochondrial function of PBMCs is a potential prognostic biomarker or therapeutic target to improve clinical outcomes in patients with lung cancer.

Elemental Characterization of Ambient Particulate Matter for a Globally Distributed Monitoring Network: Methodology and Implications.

Global ground-level measurements of elements in ambient particulate matter (PM) can provide valuable information to understand the distribution of dust and trace elements, assess health impacts, and investigate emission sources. We use X-ray fluorescence spectroscopy to characterize the elemental composition of PM samples collected from 27 globally distributed sites in the Surface PARTiculate mAtter Network (SPARTAN) over 2019-2023. Consistent protocols are applied to collect all samples and analyze them at one central laboratory, which facilitates comparison across different sites. Multiple quality assurance measures are performed, including applying reference materials that resemble typical PM samples, acceptance testing, and routine quality control. Method detection limits and uncertainties are estimated. Concentrations of dust and trace element oxides (TEO) are determined from the elemental dataset. In addition to sites in arid regions, a moderately high mean dust concentration (6 µg/m3) in PM2.5 is also found in Dhaka (Bangladesh) along with a high average TEO level (6 µg/m3). High carcinogenic risk (>1 cancer case per 100000 adults) from airborne arsenic is observed in Dhaka (Bangladesh), Kanpur (India), and Hanoi (Vietnam). Industries of informal lead-acid battery and e-waste recycling as well as coal-fired brick kilns likely contribute to the elevated trace element concentrations found in Dhaka.

Simulated Gastric Acid Promotes the Horizontal Transfer of Multidrug Resistance Genes across Bacteria in the Gastrointestinal Tract at Elevated pH Levels.

The assessment of factors that can promote the transmission of antibiotic resistance genes (ARGs) across bacteria in the gastrointestinal tract is in great demand to understand the occurrence of infections related to antibiotic-resistant bacteria (ARB) in humans. However, whether acid-resistant enteric bacteria can promote ARG transmission in gastric fluid under high-pH conditions remains unknown. This study assessed the effects of simulated gastric fluid (SGF) at different pH levels on the RP4 plasmid-mediated conjugative transfer of ARGs. Moreover, transcriptomic analysis, measurement of reactive oxygen species (ROS) levels, assessment of cell membrane permeability, and real-time quantitative assessment of the expression of key genes were performed to identify the underlying mechanisms. The frequency of conjugative transfer was the highest in SGF at pH 4.5. Antidepressant consumption and certain dietary factors further negatively impacted this situation, with 5.66-fold and 4.26-fold increases in the conjugative transfer frequency being noted upon the addition of sertraline and 10% glucose, respectively, compared with that in the control group without any additives. The induction of ROS generation, the activation of cellular antioxidant systems, increases in cell membrane permeability, and the promotion of adhesive pilus formation were factors potentially contributing to the increased transfer frequency. These findings indicate that conjugative transfer could be enhanced under certain circumstances in SGF at elevated pH levels, thereby facilitating ARG transmission in the gastrointestinal tract. IMPORTANCE The low pH of gastric acid kills unwanted microorganisms, in turn affecting their inhabitation in the intestine. Hence, studies on the factors that influence antibiotic resistance gene (ARG) propagation in the gastrointestinal tract and on the underlying mechanisms are limited. In this study, we constructed a conjugative transfer model in the presence of simulated gastric fluid (SGF) and found that SGF could promote the dissemination of ARGs under high-pH conditions. Furthermore, antidepressant consumption and certain dietary factors could negatively impact this situation. Transcriptomic analysis and a reactive oxygen species assay revealed the overproduction of reactive oxygen species as a potential mechanism by which SGF could promote conjugative transfer. This finding can help provide a comprehensive understanding of the bloom of antibiotic-resistant bacteria in the body and create awareness regarding the risk of ARG transmission due to certain diseases or an improper diet and the subsequent decrease in gastric acid levels.

Association between oxidative stress, mitochondrial function of peripheral blood mononuclear cells and gastrointestinal cancers.

BACKGROUND: The incidence and mortality rate of gastrointestinal cancers are high worldwide. Increasing studies have illustrated that the occurrence, progression, metastasis and prognosis of cancers are intimately linked to the immune system. Mitochondria, as the main source of cellular energy, play an important role in maintaining the physiological function of immune cells. However, the relationship between mitochondrial function of immune cells and tumorigenesis has not yet been systematically investigated. METHODS: A total of 150 cases, including 60 healthy donors and 90 primary gastrointestinal cancer patients without anti-tumor treatments (30 with gastric cancer, 30 with liver cancer and 30 with colorectal cancer) were involved in our study. The oxidant/antioxidant and cytokine levels in plasma, the ROS level, mitochondrial function and apoptosis ratio of peripheral blood mononuclear cells (PBMCs) were evaluated. RESULTS: The imbalance between oxidant and antioxidant in plasma was discovered in the primary gastrointestinal cancer patients. The levels of cell reactive oxygen species (ROS) and mitochondrial ROS in PBMCs of primary gastrointestinal cancers were significantly increased compared with that in healthy donors. Meanwhile, the ATP content, the mtDNA copy number and the mitochondrial membrane potential (MMP) in PBMCs of patients with primary gastrointestinal cancers were lower than those in control group. The decreased MMP also occurred in immune cells of gastrointestinal cancers, including T cell, B cell, NK cell and monocyte. Furthermore, the PBMCs apoptosis ratio of primary gastrointestinal cancer patients was significantly higher than that of control group. Importantly, an increase of IL-2 and IL-6 and a decrease of IgG in plasma were found in the patients with primary gastrointestinal cancers. These changes of mitochondrial function in immune cells were consistent among primary gastrointestinal cancers without anti-tumor treatments, such as liver cancer, gastric cancer and colorectal cancer. CONCLUSION: Our study demonstrated that the imbalance of oxidation/antioxidation in primary gastrointestinal cancer patients without anti-tumor treatments results in excessive ROS. The oxidative stress was associated to the mitochondrial dysfunction, the apoptosis of immune cells and eventually the abnormal immune function in primary gastrointestinal cancers. The application of immune cell mitochondrial dysfunction into clinical evaluation is anticipated.

MOTS-c: A promising mitochondrial-derived peptide for therapeutic exploitation.

Mitochondrial ORF of the 12S rRNA Type-C (MOTS-c) is a mitochondrial-derived peptide composed of 16 amino acids encoded by the 12S rRNA region of the mitochondrial genome. The MOTS-c protein is transferred to the nucleus during metabolic stress and directs the expression of nuclear genes to promote cell balance. Different tissues co-expressed the protein with mitochondria, and plasma also contained the protein, but its level decreased with age. In addition, MOTS-c has been shown to improve glucose metabolism in skeletal muscle, which indicates its benefits for diseases such as diabetes, obesity, and aging. Nevertheless, MOTS-c has been used less frequently in disease treatment, and no effective method of applying MOTS-c in the clinic has been developed. Throughout this paper, we discussed the discovery and physiological function of mitochondrial-derived polypeptide MOTS-c, and the application of MOTS-c in the treatment of various diseases, such as aging, cardiovascular disease, insulin resistance, and inflammation. To provide additional ideas for future research and development, we tapped into the molecular mechanisms and therapeutic potentials of MOTS-c to improve diseases and combined the technology with synthetic biology in order to offer a new approach to its development and application.

Molecular detection and genetic characteristics of Cryptosporidium spp. in Chinese racehorses.

BACKGROUND: Cryptosporidium is a protozoan parasite causing diarrhoea in humans and animals. Although Cryptosporidium has been found in domestic horses (farmed or kept at pasture), there has been only one published study of Cryptosporidium infections in Chinese racehorses, which was restricted to a very small geographical area. OBJECTIVES: To investigate the presence of Cryptosporidium spp. in the faeces of racehorses in China and to perform molecular characterisation of the parasite. STUDY DESIGN: Cross-sectional. METHODS: A total of 621 fresh faecal samples were collected for DNA extraction from racehorses at 17 equestrian clubs from 12 provinces of China from December 2016 to May 2018. All the DNA were analysed for the presence of Cryptosporidium species/genotypes and subtypes by PCR amplification of the small subunit ribosomal RNA and 60 kDa glycoprotein genes respectively. RESULTS: PCR analysis revealed that 11 samples (1.8%) were positive for Cryptosporidium spp. Among them seven samples were identified as C. parvum and four were C. hominis. The C. parvum isolates were identified as subtype IIdA14G1 (n = 4) and IIdA15G1 (n = 3), while all C. hominis isolates were identified as subtype IkA18G1 (n = 4). MAIN LIMITATIONS: A single faecal sample from each horse was used instead of multiple samples that could improve the detection rates of the parasite. CONCLUSIONS: Although Cryptosporidium infection rate was relatively low in the investigated racehorses, the presence of zoonotic subtypes IIdA14G and 1IIdA15G1 of C. parvum and IkA18G1 of C. hominis, suggesting that these animals are a potential source of Cryptosporidium in humans.

Predicting the concentrations of enteric viruses in urban rivers running through the city center via an artificial neural network.

Viral waterborne diseases are widespread in cities due largely to the occurrence of enteric viruses in urban rivers, which pose a significant concern to human health. Yet, the application of rapid detection technology for enteric viruses in environmental water remains undeveloped globally. Here, multiple linear regression (MLR) modeling and artificial neural network (ANN) modeling, which used frequently measured physicochemical parameters in river water, were constructed to predict the concentration of enteric viruses including human enteroviruses (EnVs), rotaviruses (HRVs), astroviruses (AstVs), noroviruses GⅡ (HuNoVs GⅡ), and adenoviruses (HAdVs) in rivers. After training, testing, and validating, ANN models showed better performance than any MLR model for predicting the viral concentration in Jinhe River. All determined R-values for ANN models exceeded 0.89, suggesting a strong correlation between the predicted and measured outputs for target enteric viruses. Furthermore, ANN models provided a better congruence between the observed and predicted concentrations of each virus than MLR models did. Together, these findings strongly suggest that ANN modeling can provide more accurate and timely predictions of viral concentrations based on frequent (or routine) measurements of physicochemical parameters in river water, which would improve assessments of waterborne disease prevalence in cities.

Molecular detection and genetic characterization of Cryptosporidium in kindergarten children in Southern Xinjiang, China.

Cryptosporidium is a common cause of diarrhea in children globally. However, there is limited information on the prevalence and genetic characteristics of Cryptosporidium in children in Xinjiang, China. This study aimed to assess the genetic characteristics and epidemiological status of Cryptosporidium in kindergarten children in Southern Xinjiang, China. A total of 609 fecal samples were collected from kindergartners aged 2-6 years from 11 counties in Southern Xinjiang, China. We used nested PCR amplification of the partial SSU rDNA gene to screen samples for Cryptosporidium spp. Isolates containing Cryptosporidium parvum and C. hominis were further subtyped for a gene encoding a 60-kDa glycoprotein (gp60). We used MEGA7 to construct a phylogenetic tree to study the genetic relationship between the gp60 subtypes of these two species via the Maximum Likelihood method based on the Tamura-Nei model. Only 1.3% (8/609) of asymptomatic children were confirmed to be infected with Cryptosporidium, with a 2.0% (6/299) infection rate in boys and 0.6% (2/310) infection rate in girls. Three Cryptosporidium species were identified including C. felis (37.5%; 3/8), C. hominis (37.5%; 3/8), and C. parvum (25.0%; 2/8). Three C. hominis subtypes (IbA9G3, IdA14, and IfA12G1) and two C. parvum subtypes (IIdA14G1 and IIdA15G1) were also found. This study is the first to identify the presence of Cryptosporidium in kindergarten children in Southern Xinjiang, China. The presence of zoonotic C. parvum subtypes IIdA14G1 and IIdA15G1 indicates the possible cross-species transmission of Cryptosporidium between children and animals.

Emerging pollutant metformin in water promotes the development of multiple-antibiotic resistance in Escherichia coli via chromosome mutagenesis.

Antibiotics are known to be key drivers of antibiotic resistance and antibiotic resistance gene transmission. However, the contribution of the emerging pollutant metformin in facilitating antibiotic resistance remains unclear. In this study, Escherichia coli K12 (E. coli) was exposed to metformin at concentrations ranging from 10-7 to 200 mg/L, and antibiotic susceptibility test of isolated mutants was evaluated. DNA and RNA sequencing and real-time quantitative PCR (qPCR) were performed to identify the underlying mechanisms. The results showed metformin concentrations ranging from 10-6 to 200 mg/L caused multiple-antibiotic resistance in E. coli. After 1 day exposure to metformin at 1 ng/L, the mutation frequency in E. coli increased to 1.24 × 10-8, and it further increased to 7.13 × 10-8 when prolonged to 5 days. And the mutants showed multiple-antibiotic resistance. Whole-genome DNA analysis of mutants showed chromosome mutagenesis in marR, tonB, and fhuA. Global transcriptional analysis and qPCR revealed the expressions of emrK, emrY, cusB, cusC, hycA, cecR, marA, acrA, and acrB were upregulated and those of tonB and fhuA were significantly downregulated. Thus, an increase in efflux systems AcrAB-TolC, EmrKY-TolC, and CusCFBA together with a decrease in FhuA-TonB protein complex play vital roles in the multiple-antibiotic resistance induced by metformin.

Combined exposure to non-antibiotic pharmaceutics and antibiotics in the gut synergistically promote the development of multi-drug-resistance in Escherichia coli.

The gut microbiota represents an important reservoir of antibiotic-resistant bacteria (ARB), which poses a significant threat to public health. However, little is known about the emergence of ARB in the gut after the combined exposure to antibiotics and non-antibiotic pharmaceutics. Here, Escherichia coli, a common opportunistic pathogen in the gut microbiota, was exposed to the antidepressant duloxetine (2.5 µg/L-25 mg/L) and/or chloramphenicol (6 µg/L-4 mg/L). The resistant strains were isolated to determine the minimum inhibition concentration (MIC) of 29 antibiotics. Then, genome-wide DNA sequencing, global transcriptomic sequencing, and real-time quantitative polymerase chain reaction were performed to quantify the synergy between duloxetine and chloramphenicol. Combined exposure synergistically increased the mutation frequency of chloramphenicol resistance by 2.45-9.01 fold compared with the independent exposure. A combination index reaching 187.7 indicated strong duloxetine and chloramphenicol synergy. The resultant mutants presented heritable enhanced resistance to 12 antibiotics and became ARB to eight antibiotics. Furthermore, combined exposure significantly increased the transcriptomic expression of acrA, acrB, and marA in E. coli, and generated a more robust oxidative stress response. Together with the occurrence of DNA mutations in marR in the mutants, stronger triggers to the AcrAB-TolC transport system and the MlaFEDB ABC transporter via reactive oxygen species (ROS)-induced mutagenesis, verified by gene knockout, contributed to the synergistic enhancement of antibiotic resistance in the combined exposure group. Regardless of whether their formation was induced by duloxetine, chloramphenicol, or their combination, the E. coli mutants showed 1.1-1.7-fold increases in the expression levels of acrA, acrB, acrZ, mdtE, and mdtF. This pattern indicated that the mutants shared the same resistance mechanisms against chloramphenicol, involving the improved efflux pumps AcrAB-TolC and mdtEF. Our findings demonstrated that antibiotics and non-antibiotic pharmaceutics synergistically accelerate the evolution of ARB and may enhance their spread.

Protection from benzene-induced immune dysfunction in mice.

Benzene can impair peripheral immunity and immune organs; however, the recovery of benzene impairment has rarely been reported. In this study, we developed an immune dysfunction mouse model using a benzene gavage (500 mg/kg). Female Balb/c mice were treated with Bombyx batryticatus (BB, 5 g/kg), raw pinellia (RP, 5 g/kg), or a combination of Valproic acid and Coenzyme Q10 (CM, 150 mg/kg VPA & 100 mg/kg CoQ10) medication for four weeks. The immune function of the peripheral blood mononuclear cells (PBMCs), spleen, and thymus was determined to evaluate whether the observed impairment could be altered by medications in the mouse model. Results showed that medications could alleviate benzene-induced structural and functional damage of spleen and thymus. Benzene exposure decreased the ATP level of PBMC, which can be improved by BB, RP or CM. Importantly, BB, RP or CM could relieve benzene induced-oxidative stress by increasing the activities of glutathione peroxidase (GSH) and superoxide dismutase (SOD) and decreasing the contents of malondialdehyde (MDA). In conclusion, BB, RP, and CM were able to alleviate the benzene-induced immune dysfunction and redox imbalance. Improvement of the oxidative and antioxidant imbalance may represent a mechanism by which medicine prevents benzene-induced immune dysfunction.

Seasonal monitoring of Cryptosporidium species and their genetic diversity in neonatal calves on two large-scale farms in Xinjiang, China.

To find out whether and how the prevalence and genetic diversity of Cryptosporidium in neonatal calves vary with the season, 380 fecal samples from neonatal calves on two large-scale farms in Xinjiang (Alar and Wensu) were studied using molecular biology techniques. Cryptosporidium was detected in 48.7% (185/380) of the samples and was most frequent in summer (56.8%), followed by spring (50.0%), winter (46.8%), and autumn (41.7%; p > 0.05). Calves with diarrhea seem to be more likely infected by Cryptosporidium than those without diarrhea (p < 0.01). We also found that C. parvum (n = 173), C. bovis (n = 7), and C. ryanae (n = 3) were the Cryptosporidium species detected in this study, and co-infections of these three species (n = 2) were also identified. Two subtypes (IIdA14G1 and IIdA15G1) of C. parvum were identified, and both can infect human. These results also show that neonatal calves commonly suffer diarrhea caused by C. parvum throughout the year.

Contamination sources of the enteric virus in recreational marine water shift in a seasonal pattern.

Human enteric virus occurrence in bathing beaches poses a potential health risk to swimmers. They may come from several sources, but the understanding of the seasonal contribution of contamination sources to virus occurrence is still lacking. Here, the surveillance of human enteric viruses at the First Bathing Beach in Qingdao was performed January-December 2018. The occurrence of Enteric viruses, assayed with quantitative polymerase chain reaction (qPCR), was analyzed at temporal and spatial levels to determine the viral contamination sources. The results showed that only Astroviruses (AstVs) and Adenoviruses (HAdVs) were found in the swimming area. Their occurrence correlated significantly with the sewage-polluted area, but HAdVs were only found in autumn and AstVs in spring. Meanwhile, enteric viruses in the swimming area showed significantly higher levels than the surrounding area, particularly AstVs in summer with the swimmer crowd. All these data imply that sewage discharge and swimmers co-contribute to the viral occurrence in a seasonal pattern, with the former being more focused in warm seasons (spring and autumn) and the latter in hot seasons (summer). These results indicate that sewage discharge and crowd swimmers, as unsafe swimming conditions, should be avoided to improve public health at the bathing beaches.

Unusual dominant genotype NIA1 of Enterocytozoon bieneusi in children in Southern Xinjiang, China.

Enterocytozoon bieneusi is the mainly pathologies or intestinal disorders that causes approximately 90% of reported cases of human microsporidiosis. To understand the prevalence and genotype distribution of E. bieneusi in the Xinjiang Uygur Autonomous Region, China, 609 fecal samples were collected from children in kindergarten in Southern Xinjiang and screened for this pathogen by PCR and sequencing of the internal transcribed spacer (ITS). Thirty-six fecal samples (5.9%, 36/609) were positive for E. bieneusi, with the highest prevalence observed in children from Yopurga (17.5%, 11/63). Nine genotypes were identified, of which six were known (A, CHN6, D, EbpA, KB-1, and NIA1) and three were novel (CXJH1, CXJH2 and CXJH3). Genotype NIA1 was most prevalent (52.8%, 19/36), followed by genotypes D (16.7%, 6/36), A (8.3%, 3/36), and EbpA (8.3%, 3/36). The remaining five genotypes were detected in one sample each. Phylogenetic analysis revealed that the E. bieneusi isolates clustered into two groups, one consisting of six genotypes (Group 1: A, CXJH1, D, EbpA, KB-1, and NIA1) and another consisting of three genotypes (Group 2: CHN6, CXJH2, and CXJH3). Our results confirmed that infection of E. bieneusi unusual dominant genotype NIA1 occurs in children in Xinjiang, China. Further epidemiological studies must be conducted to clarify potential sources of E. bieneusi infection in this area.

Prevalence and multilocus analysis of Giardia duodenalis in racehorses in China.

Giardia duodenalis is a zoonotic intestinal parasite infecting humans and mammals worldwide. In this study, we evaluated the prevalence of G. duodenalis in racehorses in China and genetically characterized it. In total, 621 fecal samples were collected from racehorses at 17 equestrian clubs in 15 cities in China. Forty-eight (7.7%) animals from 11 equestrian clubs were positive for G. duodenalis of assemblages A (n = 10), B (n = 36), and E (n = 2), based on the small subunit ribosomal RNA (SSU rRNA) gene. Statistically significant differences in the prevalence of this parasite were detected among the different equestrian clubs (χ2 = 49.55, df = 16, p < 0.01), whereas no significant differences were detected according to age (χ2 = 0.64, df = 1, p > 0.05) or sex (χ2 = 1.41, df = 2, p > 0.05). The G. duodenalis-positive samples were further subtyped based on three other genes, which identified 5, 4, and 4 genotypes at the triose phosphate isomerase (tpi), glutamate dehydrogenase (gdh), and ß-giardin (bg) loci, respectively. Subassemblage BIV was the predominant genotype. A phylogenetic analysis of the concatenated sequences of subassemblage BIV showed that the multilocus genotypes from the horses were genetically different from those of humans and nonhuman primates, indicating the evolution of host separation in G. duodenalis subassemblage BIV. Our study extends our understanding of the transmission of G. duodenalis between animals and humans.

Genetic diversity of Blastocystis in kindergarten children in southern Xinjiang, China.

BACKGROUND: Blastocystis is one of the most common intestinal parasites in humans and various animals worldwide. Few studies are available regarding the genetic characterization of Blastocystis infections in humans in China. METHODS: In the present study, 609 fecal samples were collected from two- to six-year-old kindergarten children in southern Xinjiang and were examined by polymerase chain reaction (PCR). RESULTS: The infection rate of Blastocystis was 14.3% (87/609); no significant difference was observed among counties and between sexes. Blastocystis subtypes ST1 (n = 38), ST2 (n = 8), and ST3 (n = 41) were identified by sequence analysis of the small subunit ribosomal RNA gene. Genetic polymorphisms were observed at the intra-subtype level, including seven variations for ST1 (ST1A to ST1G), four for ST2 (ST2A to ST2D), and two for ST3 (ST3A and ST3B); with ST1F and ST2B being new variations. CONCLUSIONS: ST1 and ST3 are the two common Blastocystis subtypes in the study area. More extensive studies in both humans and animals in different regions are needed to better characterize the transmission of Blastocystis.

Molecular Detection and Genotyping of Enterocytozoon bieneusi in Racehorses in China.

Enterocytozoon bieneusi is a widely distributed human and animal pathogen. However, few data are available on the distribution of E. bieneusi genotypes in racehorses. In this study, 621 fecal specimens were collected from racehorses at 17 equestrian clubs in 15 Chinese cities. E. bieneusi was detected via nested polymerase chain reaction (PCR) amplification of the internal transcribed spacer (ITS) gene. The overall infection rate of E. bieneusi was 4.8% (30/621). Statistically significant differences were found in the prevalence of this parasite among the equestrian clubs (χ2 = 78.464, df = 16, p < 0.01) and age groups (χ2 = 23.686, df = 1, p < 0.01), but no sex bias was found among the racehorses for the E. bieneusi infections (χ2 = 1.407, df = 2, p > 0.05). Ten E. bieneusi genotypes were identified, including seven known genotypes (EbpC, EbpA, Peru6, horse1, horse2, CAF1, and TypeIV) and three novel genotypes (HBH-1, SXH-1, and BJH-1). Phylogenetic analysis showed that EbpC, EbpA, Peru6, horse2, CAF1, TypeIV, BJH-1, and SXH-1 belonged to Group 1 of E. bieneusi, HBH-1 belonged to Group 2, and horse2 belonged to Group 6. Our findings advance the current knowledge of E. bieneusi prevalence and genotypes in racehorses in China.

Prevalence and diversity of Cryptosporidium spp. in bamboo rats (Rhizomys sinensis) in South Central China.

Cryptosporidium is one of the most prevalent zoonotic parasites and is responsible for the high burden of diarrheal disease across the globe. Rodents are globally overpopulated and are reservoirs for a variety of zoonotic pathogens. Bamboo rats are a common species of rodent that are bred for meat and wool in China. However, the genetic characterization of Cryptosporidium in bamboo rats in China is limited. The aim of this study was to determine the occurrence and genetic characterization of Cryptosporidium in bamboo rats from South Central China. From February2017to February 2018, 435 fecal samples were collected from bamboo rats in 13 farms located in 12 cities in South Central China. All fecal specimens were examined for Cryptosporidium by PCR, and through sequencing the partial small subunit of ribosomal DNA (SSU rRNA). C. parvum-positive samples were further subtyped through analysis of the 60-kDa glycoprotein (gp60) gene sequence. Meanwhile, all the new Cryptosporidium genotypes samples were selected for further sequence characterization at the 70-kDa heat shock protein (HSP70) gene and oocyst wall protein (COWP) gene as well as gp60 gene. Infection rates of 2.1% (9/435) were recorded for Cryptosporidium. Sequence analysis confirmed the presence of two Cryptosporidium species including C. parvum (n = 2), C. occultus (n = 1) and two new Cryptosporidium genotypes termed Cryptosporidium bamboo rat genotype I (n = 5) and Cryptosporidium bamboo rat genotype II (n = 1). Two subtypes of C. parvum were identified including IIdA15G1 and IIpA19 (one each).The discovery of zoonotic Cryptosporidium species/genotypes in bamboo rats suggests they have significant zoonotic potential and pose a threat to human health. The novel sequences discovered provide new insight into genotypic variations in Cryptosporidium in bamboo rats.