The gut microbiome has long been known to play fundamentally important roles in the animal health and the well-being of its host. As such, the establishment and maintenance of a beneficial gut microbiota early in life...The gut microbiome has long been known to play fundamentally important roles in the animal health and the well-being of its host. As such, the establishment and maintenance of a beneficial gut microbiota early in life is crucial in pigs, since early gut colonizers are pivotal in the establishment of permanent microbial community structures affecting the health and growth performance of pigs later in life. Emphasizing this importance of early gut colonizers, it is critical to understand the factors impacting the establishment of the piglet gut microbiome at weaning. Factors include, among others, diet, in-feed antibiotics, probiotics and prebiotic administration. The impact of these factors on establishment of the gut microbiome of piglets at weaning includes effects on piglet gut microbial diversity, structure, and succession. In this review, we thoroughly reviewed the most recent findings on the piglet gut microbiome shifts as influenced by weaning, and how these microbiome changes brought about by various factors that have been shown to affect the development of microbiota in piglets. This review will provide a general overview of recent studies that can help to facilitate the design of new strategies to modulate the gut microbiome in order to enhance gastrointestinal health, growth performance and well-being of piglets.展开更多
Background: Gonocytes give rise to spermatogonial stem cells, and thereby play an essential role in establishing spermatogenesis. Optimized culture conditions for gonocytes provide an opportunity for their study and i...Background: Gonocytes give rise to spermatogonial stem cells, and thereby play an essential role in establishing spermatogenesis. Optimized culture conditions for gonocytes provide an opportunity for their study and in vitro manipulation for potential application in reproductive technologies. Using six experiments in a step-wise design, we examined the effects of several culture conditions on the maintenance, proliferation, and colony formation of porcine gonocytes. Testis cells from neonatal piglets were cultured for 7 d in DMEM supplemented with 10% fetal bovine serum. The examined culture conditions included using different cell seeding densities, gonocyte proportions, incubation temperatures, sampling strategies, and medium changing regimens.Results: Confluency of cel s was optimal(>90% by ~6 d) when 3.0 × 104 testis cel s/cm2 containing ~40% gonocytes were used. Incubating the cel s at 35 °C or 37 °C resulted in similar cel number and viability at confluency, but incubation at 35 °C resulted in a delayed confluency. In the first 2 d of culture, gonocytes remained mostly floating in the medium and gradual y settled over the next 5 d. Consequently, not changing the medium for 7 d(as opposed to changing it every 2 d) led to a significant increase in the number of gonocyte colonies by reducing the loss of "floating gonocytes".Conclusion: We found that gonocytes require the presence of a critical minimum number of somatic cel s for settlement, and can proliferate and form growing colonies even in a basic medium. Large numbers of viable gonocytes remain floating in the medium for several days. The optimized culture conditions in the present study included seeding with 3.0 × 104 testis cel s/cm2 containing ~40% gonocytes, incubating at 37 °C, and without changing the medium in the first week, which can result in improved colony formation of porcine gonocytes.展开更多
The coronavirus disease 2019(COVID-19)pandemic is challenging the current public health emergency response systems(PHERSs)of many countries.Although environmental factors,such as those influencing the survival of viru...The coronavirus disease 2019(COVID-19)pandemic is challenging the current public health emergency response systems(PHERSs)of many countries.Although environmental factors,such as those influencing the survival of viruses and their transmission between species including humans,play important roles in PHERSs,little attention has been given to these factors.This study describes and elucidates the roles of environmental factors in future PHERSs.To improve countries’capability to respond to public health emergencies associated with viral infections such as the COVID-19 pandemic,a number of environmental factors should be considered before,during,and after the responses to such emergencies.More specifically,to prevent pandemic outbreaks,we should strengthen environmental and wildlife protection,conduct detailed viral surveillance in animals and hotspots,and improve early-warning systems.During the pandemic,we must study the impacts of environmental factors on viral behaviors,develop control measures to minimize secondary environmental risks,and conduct timely assessments of viral risks and secondary environmental effects with a view to reducing the impacts of the pandemic on human health and on ecosystems.After the pandemic,we should further strengthen surveillance for viruses and the prevention of viral spread,maintain control measures for minimizing secondary environmental risks,develop our capability to scientifically predict pandemics and resurgences,and prepare for the next unexpected resurgence.Meanwhile,we should restore the normal life and production of the public based on the“One Health”concept,that views global human and environmental health as inextricably linked.Our recommendations are essential for improving nations’capability to respond to global public health emergencies.展开更多
Background: Understanding the composition of the microbial community and its functional capacity during weaning is important for pig production as bacteria play important roles in the pig’s health and growth performa...Background: Understanding the composition of the microbial community and its functional capacity during weaning is important for pig production as bacteria play important roles in the pig’s health and growth performance. However,limited information is available regarding the composition and function of the gut microbiome of piglets in early-life.Therefore, we performed 16 S rRNA gene and whole metagenome shotgun sequencing of DNA from fecal samples from healthy piglets during weaning to measure microbiome shifts, and to identify the potential contribution of the early-life microbiota in shaping piglet health with a focus on microbial stress responses, carbohydrate and amino acid metabolism.Results: The analysis of 16 S rR NA genes and whole metagenome shotgun sequencing revealed significant compositional and functional differences between the fecal microbiome in nursing and weaned piglets. The fecal microbiome of the nursing piglets showed higher relative abundance of bacteria in the genus Bacteroides with abundant gene families related to the utilization of lactose and galactose. Prevotel a and Lactobacil us were enriched in weaned piglets with an enrichment for the gene families associated with carbohydrate and amino acid metabolism. In addition, an analysis of the functional capacity of the fecal microbiome showed higher abundances of genes associated with heat shock and oxidative stress in the metagenome of weaned piglets compared to nursing piglets.Conclusions: Overal, our data show that microbial shifts and changes in functional capacities of the piglet fecal microbiome resulted in potential reductions in the effects of stress, including dietary changes that occur during weaning.These results provide us with new insights into the piglet gut microbiome that contributes to the growth of the animal.展开更多
Alzheimer＇s disease （AD） is a prevalent and debilitating neurodegenerative disorder in the elderly. The etiology of AD has not been fully defined and currently there is no cure for this devastating disease. Compell...Alzheimer＇s disease （AD） is a prevalent and debilitating neurodegenerative disorder in the elderly. The etiology of AD has not been fully defined and currently there is no cure for this devastating disease. Compelling evidence sug- gests that the immune system plays a critical role in the pathophysiology ofAD. Autoantibodies against a variety of molecules have been associated with AD. The roles of these autoantibodies in AD, however, are not well understood. This review attempts to summarize recent findings on these autoantibodies and explore their potential as diagnostic/ prognostic biomarkers for AD, their roles in the pathogenesis of AD, and their implications in the development of effective immunotherapies for AD.展开更多
Measurement of fecal cytokines has been used as a marker of intestinal inflammation in people and correlates with endoscopic findings. The aim of this study was to evaluate the use of canine-specific enzyme-linked imm...Measurement of fecal cytokines has been used as a marker of intestinal inflammation in people and correlates with endoscopic findings. The aim of this study was to evaluate the use of canine-specific enzyme-linked immunosorbant assays (ELISAs) for quantification of cytokines in canine fecal samples as a non-invasive biomarker. Interleukin (IL)-6, -8, -10, -23/12p40 and TNF-a were assessed by using spiked fecal samples from 3 healthy dogs. Standard curve validation was performed, and the impact of time to freeze, duration of storage and number of freeze-thaw cycles on cytokine concentration were also examined. All the cytokines assayed could be detected, with varying accuracy. The mean coefficient of variation (CV) for all standard curves ranged from 2.95%-9.8%. The mean intra-assay CV ranged from 3.1%-11.14%, and inter-assay CV from 4.36%-18.83%. Recovery of IL-23 was poor (7.23%-17.12%), precluding further interpretation of stability studies. Mean recovery did not appear to be affected by time to freeze and repeat freeze-thaw cycles in all cytokines investigated. Recovery for all cytokines after short-term storage of 30 days at -80℃ showed a recovery of 70% or >130%. In conclusion, although fecal IL-6, -8, -10, and TNF-a could be used as biomarkers of intestinal inflammation in the dog, the quality of laboratory performance and poor recovery at lower concentrations limit their application. Bench-top and freeze-thaw stability was acceptable, and samples should ideally be analyzed within a week. Investigation involving dogs with acute and chronic inflammatory intestinal disease is required to determine the role of this methodology in a clinical setting.展开更多
Recent advances in reprograming somatic cells from normal and diseased tissues into induced pluripotent stem cells (iPSCs) provide exciting possibilities for generating renewed tissues for disease modeling and therapy...Recent advances in reprograming somatic cells from normal and diseased tissues into induced pluripotent stem cells (iPSCs) provide exciting possibilities for generating renewed tissues for disease modeling and therapy. However, questions remain on whether iPSCs still retain certain markers (e.g. aging) of the original somatic cells that could limit their replicative potential and utility. A reliable biological marker for measuring cellular aging is telomere length, which is maintained by a specialized form of cellular polymerase known as telomerase. Telomerase is composed of the cellular reverse transcriptase protein, the integral RNA component, and other cellular proteins (e.g. dyskerin). Mutations in any of these components of telomerase can lead to a severe form of marrow def iciency known as dyskeratosis congenita (DC). This review summarizes recent f indings on the effect of cellular reprograming via iPS of normal or DC patient-derived tissues on telomerase function and consequently on telomere length maintenance. The potentials and challenges of using iPSCs in a clinical setting will also be discussed.展开更多
Dear Editor,Viruses are intracellular parasites that depend on cellular components to replicate.Viruses communicate withthe cellular machinery through protein–protein interactions(PPIs),for which each individual viru...Dear Editor,Viruses are intracellular parasites that depend on cellular components to replicate.Viruses communicate withthe cellular machinery through protein–protein interactions(PPIs),for which each individual virus encodes aunique array of proteins.Each viral protein is capable ofindependently interacting with multiple cellular展开更多
Background:Microbiota development is a critical aspect of turkey poult maturation,and the succession of microbes in the turkey gut has been shown to correlate with poult performance.The purpose of this study was to de...Background:Microbiota development is a critical aspect of turkey poult maturation,and the succession of microbes in the turkey gut has been shown to correlate with poult performance.The purpose of this study was to determine the fate of the microbiota in turkey poults after movement of birds first raised in an isolated hatch brood system into a more traditional commercial brood facility with pre-existing birds.Turkey poults were first divided into groups raised in conventional brood pens from day-of-hatch and those raised in an experimental hatch brood system.After 11 days of growth,hatch brood birds were moved into pens within the conventional brood barn and monitored for an additional 18 days.Sampling of both hatch brood and conventional pen birds was performed at multiple timepoints throughout the study,and cecal content was used to analyze the bacterial microbiota using 16S rRNA gene amplicon sequencing.Results:Alpha diversity tended to be higher in samples from conventional pen birds compared to those from hatch brood birds prior to the day 11 move,but the difference between systems was not observed post-move.Using beta diversity metrics,bacterial community succession appeared delayed in the hatch brood system birds pre-move,but post-move community composition quickly converged with that of the conventional pen birds.This was validated through assessment of significantly different genera between hatch brood system and conventional pen birds,where numbers of significantly different taxa quickly decreased following the move.Some key taxa previously associated with poult performance were delayed in their appearance and relative abundance in hatch brood birds.Conclusions:Overall,this study demonstrates that the use of isolated hatch brood systems has an impact on the poult gut microbiota,but its impact is resolved quickly once the birds are introduced into a conventional brood environment.Therefore,the benefits of pathogen reduction with hatch brood systems may outweigh negative microbiota impacts due to isolation.展开更多
Six different kinds of non-metallic or organic disinfectants were obtained in this research study including “Neutral Electrolyzed Water”, “M22” organic disinfectant solution, Superoxy Food Wash disinfectant, Hydro...Six different kinds of non-metallic or organic disinfectants were obtained in this research study including “Neutral Electrolyzed Water”, “M22” organic disinfectant solution, Superoxy Food Wash disinfectant, Hydrogen Peroxide, Clorox Germicidal Bleach and Clidox-S. The effectiveness of these disinfectants was studied against various subtypes of avian influenza virus (AIV). The virus-disinfectant mixtures were prepared in serial dilutions of each disinfectant with a constant virus titer and incubated at ambient temperature in different time intervals for virus inactivation. The virus inactivation results were determined by virus recovery in embryonating chicken eggs. Among the six different kinds of nonmetallic disinfectants obtained for this research project, Neutral Electrolyzed Water, “M22” solution, Clorox Germicidal Bleach and Clidox-S were effectively inactivated AIV with appropriate working dilutions and reaction times. Superoxy Food Wash disinfectant and Hydrogen Peroxide were found having limited effect on virus inactivation with extended exposure times of more than 2 hours. These research findings provide scientific data to poultry industry with guidelines to select and use non-metallic organic disinfectants for poultry flock sanitation and disinfection to effectively prevent and control of avian influenza outbreaks.展开更多
Introduction Vascular endothelial (VE)-cadherin is localized to the endothelial borders and the adherens junctions,which are regulated by changes in mitogen activated protein kinases (MAPK),GTPases,and intracellular c...Introduction Vascular endothelial (VE)-cadherin is localized to the endothelial borders and the adherens junctions,which are regulated by changes in mitogen activated protein kinases (MAPK),GTPases,and intracellular calcium. We previously展开更多
Objective:To carry out the genetic characterization and evolutionary analysis of three avian orthoavulavirus 1(AOAV-1)isolates from poultry workers with respiratory symptoms.Methods:Using Illumina Mi Seq,whole-genome ...Objective:To carry out the genetic characterization and evolutionary analysis of three avian orthoavulavirus 1(AOAV-1)isolates from poultry workers with respiratory symptoms.Methods:Using Illumina Mi Seq,whole-genome sequencing was carried out to assess the evolutionary dynamics of three AOAV-1 isolates.A phylogenetic and comparative analysis of all coding genes was done using bioinformatics tools.Results:Phylogenetic analysis and genetic distance estimation suggested a close relationship among human-and avian-originated velogenic strains of genotypeⅩⅢ,sub-genotypeⅩⅢ.2.1.Several substitutions in the significant structural and biological motifs were exclusively identified in the human-originated strains.Conclusions:To our knowledge,this is the first report of a velogenic AOAV-1 isolate from natural infection of the human upper respiratory tract.Our findings highlight the evolution and zoonotic potential of velogenic AOAV-1 in a disease endemic setting.展开更多
Whenever there is no adequate DNA replication <em>in vitro</em>, there are alternatives strategies to insert a piece of DNA into a convenient replicon such as small plasmids and bacteriophages. These are c...Whenever there is no adequate DNA replication <em>in vitro</em>, there are alternatives strategies to insert a piece of DNA into a convenient replicon such as small plasmids and bacteriophages. These are called vectors or cloning vehicles. These days, there is a high demand to manufacture recombinant and nanobodies which are required in biomedical research and for therapeutic and diagnostic purposes. In order to do so, <em>E. coli</em>, insect cells, or mammalian cells have been used to express and purify protein for nanobody production. This paper explains the experimental trials on the cloning of the Nanobody cDNA mock-up in pHEN6c plasmid vector from the subcultured <em>E. coli</em> sample taken from the lab. The concentration and purity of DNA plasmid were evaluated by UV spectrophotometer and agarose gel electrophoresis following plasmid DNA Purification from <em>E. coli</em> by alkaline lysis. Based on this, the concentration of the isolated pHEN6c plasmid DNA was found 44.7 ng/μl or 0.0447 μg/μl. Whereas, the purity at absorbance (A260/A280) was 0.893/0.501 = 1.78. Moreover, its yield was 2.235 μg. In addition, its transformation efficiency was 21.68 μg/μl. On the other hand, the molecular weight of the Nanobody and vector were 569 and 2717 respectively. Generally, most of the protocols used to clone a fragment of DNA, might not work very well with PCR products.展开更多
Rottweilers are predisposed to eosinophilic diseases, including hypereosinophilic syndrome. The immunopathogenesis of idiopathic eosinophilia is poorly characterised in dogs and man. Studies in people have suggested c...Rottweilers are predisposed to eosinophilic diseases, including hypereosinophilic syndrome. The immunopathogenesis of idiopathic eosinophilia is poorly characterised in dogs and man. Studies in people have suggested cytokines, particularly interleukin (IL)-5, play a role in instigating and perpetuating eosinophilia. This study sought to establish whether differences in gene expression, and concentration of selected, cytokines and chemokines were associated with eosinophilia in Rottweilers. Quantitative real-time reverse transcriptase polymerase chain reaction (qRT-PCR) assays were used to quantify messenger ribonucleic acid (mRNA) encoding cytokines IL-4, -5, -10, -12p19, -12p35, -12p40, -18, interferon gamma (IFN-γ) and chemokines eotaxin-2 and -3 from peripheral blood mononuclear cell (PMBC) samples obtained from healthy dogs (breeds other than Rottweiler) with normal eosinophil blood counts (n = 5) and Rottweilers with normal (n = 6), mildly increased (n = 7) and high (n = 3) eosinophil blood counts. Quantification of plasma IFN-γ and IL-5 was performed using commercially available canine-specific enzyme-linked immunosorbent assays ELISAs. Cytokine mRNA was measurable in all samples, although eotaxin-2 and -3 were not detected. No significant differences in gene expression of any cytokine were found between groups (based on eosinophil count or breed). No significant difference in plasma IL-5 or IFN-γ concentration was present between groups. In conclusion, there were no significant differences in cytokine mRNA profiles or plasma IL-5 and IFN-γ levels between Rottweilers with increased eosinophil counts and Rottweiler and non-Rottweiler dogs with normal eosinophil counts.展开更多
Avian influenza (AI) virology surveillance is the most important method to monitor AI virus (AIV) in poultry so as to effectively prevent and control AI outbreaks. Monoclonal antibodies (MAb)-based assays are highly s...Avian influenza (AI) virology surveillance is the most important method to monitor AI virus (AIV) in poultry so as to effectively prevent and control AI outbreaks. Monoclonal antibodies (MAb)-based assays are highly sensitive and specific for AIV detection, and much practical and economic for test-in-field or onsite. Many such assays have been developed and are still in developing since the H5N1 highly pathogenic AI (HPAI) outbreaks occurred in South East Asia in 2003. A MAb-based dot-enzyme-linked immunosorbent assay (ELISA) has been developed in our lab during late 1990s and early 2000s. Meanwhile, AIV H7 and H5 subtype specific-MAbs have been successfully developed in our laboratory to enhance the Dot-ELISA and other MAb-based assays for AIV detection. Production and purification of the H7 and H5 MAbs were made to provide essential reagents for Dot-ELISA and other immunoassays, and the current development of a novel Biosensor technique for rapid detection of AIV from clinical and field specimens.展开更多
Escherichia coli O157:H7 is a human pathogen that was first identified from a foodborne outbreak in 1982, and in the 25 years that followed, many new strains were identified and emerged in numerous outbreaks of human ...Escherichia coli O157:H7 is a human pathogen that was first identified from a foodborne outbreak in 1982, and in the 25 years that followed, many new strains were identified and emerged in numerous outbreaks of human disease. Extensive research has been conducted to identify virulence factor genes involved in the pathogenesis of E. coli O157:H7 and many genome sequences of E. coli O157:H7 strains have become available to the scientific community. Here, we provide a comprehensive overview of the research that has been conducted over the first 25 years to identify 394 known or putative virulence factor genes present in the genomes of E. coli O157:H7 strains. Finally, an examination of the conservation of these 394 virulence factor genes across additional genomes of E. coli O157:H7 is provided which summarizes the first 25 years and 13 genomes of this human pathogen.展开更多
The bacterium Helicobacter pylori(H.pylori)infects the stomachs of approximately 50%of all humans.With its universal occurrence,high infectivity and virulence properties it is considered as one of the most severe glob...The bacterium Helicobacter pylori(H.pylori)infects the stomachs of approximately 50%of all humans.With its universal occurrence,high infectivity and virulence properties it is considered as one of the most severe global burdens of modern humankind.It has accompanied humans for many thousands of years,and due to its high genetic variability and vertical transmission,its population genetics reflects the history of human migrations.However,especially complex demographic events such as the colonisation of Europe cannot be resolved with population genetic analysis of modern H.pylori strains alone.This is best exemplified with the reconstruction of the 5300-year-old H.pylori genome of the Iceman,a European Copper Age mummy.Our analysis provided precious insights into the ancestry and evolution of the pathogen and underlined the high complexity of ancient European population history.In this review we will provide an overview on the molecular analysis of H.pylori in mummified human remains that were done so far and we will outline methodological advancements in the field of ancient DNA research that support the reconstruction and authentication of ancient H.pylori genome sequences.展开更多
Increasing numbers of amphibian species require conservation breeding programs for their survival.A major challenge is the efficient rearing of tadpoles,many of which require complex habitats and specialised diets.Aqu...Increasing numbers of amphibian species require conservation breeding programs for their survival.A major challenge is the efficient rearing of tadpoles,many of which require complex habitats and specialised diets.Aquatic tadpoles of the West Australian frog Litoria moorei were kept at low density(1 tadpole per 1.95 litres water) in aquaria at 25℃.Fed on a staple diet of boiled lettuce and leaf litter,group of diets were supplemented with either control,Wardley Premium Spirulina Discs,Sera~(TM) GVG-mix tropical fish food,or a combination of Wardley Premium Spirulina discs and Sera~(TM) GVG-mix fish food.There was a relatively high loss(i.e.,found dead,euthanized due to scoliosis,or not found) of tadpoles fed with the lettuce/leaf litter alone,but this was increased significantly when supplemented with Wardley Premium Spirulina discs,either alone or with Sera~(TM) GVG-mix fish food,and Sera~(TM) GVG fish food alone.However,the survived tadpoles fed on the three supplements were all heavier after three weeks and at metamorphosis than those fed with lettuce/leaf litter alone,and reached metamorphosis quicker.It is concluded that any benefit of the food supplements in terms of increasing the rate of growth and development of the tadpoles is outweighed by greater mortality.There is now a need for the efficient rearing of tadpoles,many from novel species that need complex habitats.Further studies of diet are required due to the current conservation crisis of amphibians.展开更多
Lake ecosystems confront escalating challenges to their stability and resilience,most intuitively leading to biodiversity loss,necessitating effective preservation strategies to safeguard aquatic environments.However,...Lake ecosystems confront escalating challenges to their stability and resilience,most intuitively leading to biodiversity loss,necessitating effective preservation strategies to safeguard aquatic environments.However,the complexity of ecological processes governing lake biodiversity under multi-stressor interactions remains an ongoing concern,primarily due to insufficient long-term bioindicator data,particularly concerning macroinvertebrate biodiversity.Here we utilize a unique,continuous,and in situ biomonitoring dataset spanning from 2011 to 2019 to investigate the spatio-temporal variation of macroinvertebrate communities.We assess the impact of four crucial environmental parameters on Lake Dongting and Lake Taihu,i.e.,water quality,hydrology,climate change,and land use.These two systems are representative of lakes with Yangtze-connected and disconnected subtropical floodplains in China.We find an alarming trend of declining taxonomic and functional diversities among macroinvertebrate communities despite improvements in water quality.Primary contributing factors to this decline include persistent anthropogenic pressures,particularly alterations in human land use around the lakes,including intensified nutrient loads and reduced habitat heterogeneity.Notably,river-lake connectivity is pivotal in shaping differential responses to multiple stressors.Our results highlight a strong correlation between biodiversity alterations and land use within a 2e5 km radius and 0.05e2.5 km from the shorelines of Lakes Dongting and Taihu,respectively.These findings highlight the importance of implementing land buffer zones with specific spatial scales to enhance taxonomic and functional diversity,securing essential ecosystem services and enhancing the resilience of crucial lake ecosystems.展开更多
基金supported by the fund(Project No.PJ012615),Rural Development Administration,Republic of Korea
文摘The gut microbiome has long been known to play fundamentally important roles in the animal health and the well-being of its host. As such, the establishment and maintenance of a beneficial gut microbiota early in life is crucial in pigs, since early gut colonizers are pivotal in the establishment of permanent microbial community structures affecting the health and growth performance of pigs later in life. Emphasizing this importance of early gut colonizers, it is critical to understand the factors impacting the establishment of the piglet gut microbiome at weaning. Factors include, among others, diet, in-feed antibiotics, probiotics and prebiotic administration. The impact of these factors on establishment of the gut microbiome of piglets at weaning includes effects on piglet gut microbial diversity, structure, and succession. In this review, we thoroughly reviewed the most recent findings on the piglet gut microbiome shifts as influenced by weaning, and how these microbiome changes brought about by various factors that have been shown to affect the development of microbiota in piglets. This review will provide a general overview of recent studies that can help to facilitate the design of new strategies to modulate the gut microbiome in order to enhance gastrointestinal health, growth performance and well-being of piglets.
基金financially supported by grants from the Natural Science of Engineering Research and Council(NSERC)of Canada awarded to A.HonaramoozGraduate student scholarships to A.H.Awang-Junaidi were provided by the Ministry of Higher Education of Malaysia,the University of Saskatchewan College of Graduate and Postdoctoral Studiesthe University of Saskatchewan Western College of Veterinary Medicine
文摘Background: Gonocytes give rise to spermatogonial stem cells, and thereby play an essential role in establishing spermatogenesis. Optimized culture conditions for gonocytes provide an opportunity for their study and in vitro manipulation for potential application in reproductive technologies. Using six experiments in a step-wise design, we examined the effects of several culture conditions on the maintenance, proliferation, and colony formation of porcine gonocytes. Testis cells from neonatal piglets were cultured for 7 d in DMEM supplemented with 10% fetal bovine serum. The examined culture conditions included using different cell seeding densities, gonocyte proportions, incubation temperatures, sampling strategies, and medium changing regimens.Results: Confluency of cel s was optimal(>90% by ~6 d) when 3.0 × 104 testis cel s/cm2 containing ~40% gonocytes were used. Incubating the cel s at 35 °C or 37 °C resulted in similar cel number and viability at confluency, but incubation at 35 °C resulted in a delayed confluency. In the first 2 d of culture, gonocytes remained mostly floating in the medium and gradual y settled over the next 5 d. Consequently, not changing the medium for 7 d(as opposed to changing it every 2 d) led to a significant increase in the number of gonocyte colonies by reducing the loss of "floating gonocytes".Conclusion: We found that gonocytes require the presence of a critical minimum number of somatic cel s for settlement, and can proliferate and form growing colonies even in a basic medium. Large numbers of viable gonocytes remain floating in the medium for several days. The optimized culture conditions in the present study included seeding with 3.0 × 104 testis cel s/cm2 containing ~40% gonocytes, incubating at 37 °C, and without changing the medium in the first week, which can result in improved colony formation of porcine gonocytes.
基金the National Science Foundation of China(41925031,41991315,and 41521003).
文摘The coronavirus disease 2019(COVID-19)pandemic is challenging the current public health emergency response systems(PHERSs)of many countries.Although environmental factors,such as those influencing the survival of viruses and their transmission between species including humans,play important roles in PHERSs,little attention has been given to these factors.This study describes and elucidates the roles of environmental factors in future PHERSs.To improve countries’capability to respond to public health emergencies associated with viral infections such as the COVID-19 pandemic,a number of environmental factors should be considered before,during,and after the responses to such emergencies.More specifically,to prevent pandemic outbreaks,we should strengthen environmental and wildlife protection,conduct detailed viral surveillance in animals and hotspots,and improve early-warning systems.During the pandemic,we must study the impacts of environmental factors on viral behaviors,develop control measures to minimize secondary environmental risks,and conduct timely assessments of viral risks and secondary environmental effects with a view to reducing the impacts of the pandemic on human health and on ecosystems.After the pandemic,we should further strengthen surveillance for viruses and the prevention of viral spread,maintain control measures for minimizing secondary environmental risks,develop our capability to scientifically predict pandemics and resurgences,and prepare for the next unexpected resurgence.Meanwhile,we should restore the normal life and production of the public based on the“One Health”concept,that views global human and environmental health as inextricably linked.Our recommendations are essential for improving nations’capability to respond to global public health emergencies.
基金supported by the fund(Project No.PJ012615)Rural Development Administration,Republic of Korea
文摘Background: Understanding the composition of the microbial community and its functional capacity during weaning is important for pig production as bacteria play important roles in the pig’s health and growth performance. However,limited information is available regarding the composition and function of the gut microbiome of piglets in early-life.Therefore, we performed 16 S rRNA gene and whole metagenome shotgun sequencing of DNA from fecal samples from healthy piglets during weaning to measure microbiome shifts, and to identify the potential contribution of the early-life microbiota in shaping piglet health with a focus on microbial stress responses, carbohydrate and amino acid metabolism.Results: The analysis of 16 S rR NA genes and whole metagenome shotgun sequencing revealed significant compositional and functional differences between the fecal microbiome in nursing and weaned piglets. The fecal microbiome of the nursing piglets showed higher relative abundance of bacteria in the genus Bacteroides with abundant gene families related to the utilization of lactose and galactose. Prevotel a and Lactobacil us were enriched in weaned piglets with an enrichment for the gene families associated with carbohydrate and amino acid metabolism. In addition, an analysis of the functional capacity of the fecal microbiome showed higher abundances of genes associated with heat shock and oxidative stress in the metagenome of weaned piglets compared to nursing piglets.Conclusions: Overal, our data show that microbial shifts and changes in functional capacities of the piglet fecal microbiome resulted in potential reductions in the effects of stress, including dietary changes that occur during weaning.These results provide us with new insights into the piglet gut microbiome that contributes to the growth of the animal.
基金supported in part by grants from the National Institute of Health(HL117652)(to JW)the Academic Health Center(Faculty Research Development Program) of the University of Minnesota (to LL and JW)
文摘Alzheimer＇s disease （AD） is a prevalent and debilitating neurodegenerative disorder in the elderly. The etiology of AD has not been fully defined and currently there is no cure for this devastating disease. Compelling evidence sug- gests that the immune system plays a critical role in the pathophysiology ofAD. Autoantibodies against a variety of molecules have been associated with AD. The roles of these autoantibodies in AD, however, are not well understood. This review attempts to summarize recent findings on these autoantibodies and explore their potential as diagnostic/ prognostic biomarkers for AD, their roles in the pathogenesis of AD, and their implications in the development of effective immunotherapies for AD.
文摘Measurement of fecal cytokines has been used as a marker of intestinal inflammation in people and correlates with endoscopic findings. The aim of this study was to evaluate the use of canine-specific enzyme-linked immunosorbant assays (ELISAs) for quantification of cytokines in canine fecal samples as a non-invasive biomarker. Interleukin (IL)-6, -8, -10, -23/12p40 and TNF-a were assessed by using spiked fecal samples from 3 healthy dogs. Standard curve validation was performed, and the impact of time to freeze, duration of storage and number of freeze-thaw cycles on cytokine concentration were also examined. All the cytokines assayed could be detected, with varying accuracy. The mean coefficient of variation (CV) for all standard curves ranged from 2.95%-9.8%. The mean intra-assay CV ranged from 3.1%-11.14%, and inter-assay CV from 4.36%-18.83%. Recovery of IL-23 was poor (7.23%-17.12%), precluding further interpretation of stability studies. Mean recovery did not appear to be affected by time to freeze and repeat freeze-thaw cycles in all cytokines investigated. Recovery for all cytokines after short-term storage of 30 days at -80℃ showed a recovery of 70% or >130%. In conclusion, although fecal IL-6, -8, -10, and TNF-a could be used as biomarkers of intestinal inflammation in the dog, the quality of laboratory performance and poor recovery at lower concentrations limit their application. Bench-top and freeze-thaw stability was acceptable, and samples should ideally be analyzed within a week. Investigation involving dogs with acute and chronic inflammatory intestinal disease is required to determine the role of this methodology in a clinical setting.
基金Supported by A Research Scholar Grant of the American Cancer Society (RSG-06-162-01-GMC)
文摘Recent advances in reprograming somatic cells from normal and diseased tissues into induced pluripotent stem cells (iPSCs) provide exciting possibilities for generating renewed tissues for disease modeling and therapy. However, questions remain on whether iPSCs still retain certain markers (e.g. aging) of the original somatic cells that could limit their replicative potential and utility. A reliable biological marker for measuring cellular aging is telomere length, which is maintained by a specialized form of cellular polymerase known as telomerase. Telomerase is composed of the cellular reverse transcriptase protein, the integral RNA component, and other cellular proteins (e.g. dyskerin). Mutations in any of these components of telomerase can lead to a severe form of marrow def iciency known as dyskeratosis congenita (DC). This review summarizes recent f indings on the effect of cellular reprograming via iPS of normal or DC patient-derived tissues on telomerase function and consequently on telomere length maintenance. The potentials and challenges of using iPSCs in a clinical setting will also be discussed.
基金supported in part by the South Dakota Agricultural Experiment Station and the South Dakota 2010 Research Center,BCAAP(Biological Control and Analysis of Applied Photonics)Fund(3AH203 and 3SJ163 to FL)
文摘Dear Editor,Viruses are intracellular parasites that depend on cellular components to replicate.Viruses communicate withthe cellular machinery through protein–protein interactions(PPIs),for which each individual virus encodes aunique array of proteins.Each viral protein is capable ofindependently interacting with multiple cellular
基金supported by Agriculture and Food Research Initiative competitive grants 2016-67015-24911 and 2018-68003-27464 from the USDA National Institute of Food and Agriculture.
文摘Background:Microbiota development is a critical aspect of turkey poult maturation,and the succession of microbes in the turkey gut has been shown to correlate with poult performance.The purpose of this study was to determine the fate of the microbiota in turkey poults after movement of birds first raised in an isolated hatch brood system into a more traditional commercial brood facility with pre-existing birds.Turkey poults were first divided into groups raised in conventional brood pens from day-of-hatch and those raised in an experimental hatch brood system.After 11 days of growth,hatch brood birds were moved into pens within the conventional brood barn and monitored for an additional 18 days.Sampling of both hatch brood and conventional pen birds was performed at multiple timepoints throughout the study,and cecal content was used to analyze the bacterial microbiota using 16S rRNA gene amplicon sequencing.Results:Alpha diversity tended to be higher in samples from conventional pen birds compared to those from hatch brood birds prior to the day 11 move,but the difference between systems was not observed post-move.Using beta diversity metrics,bacterial community succession appeared delayed in the hatch brood system birds pre-move,but post-move community composition quickly converged with that of the conventional pen birds.This was validated through assessment of significantly different genera between hatch brood system and conventional pen birds,where numbers of significantly different taxa quickly decreased following the move.Some key taxa previously associated with poult performance were delayed in their appearance and relative abundance in hatch brood birds.Conclusions:Overall,this study demonstrates that the use of isolated hatch brood systems has an impact on the poult gut microbiota,but its impact is resolved quickly once the birds are introduced into a conventional brood environment.Therefore,the benefits of pathogen reduction with hatch brood systems may outweigh negative microbiota impacts due to isolation.
文摘Six different kinds of non-metallic or organic disinfectants were obtained in this research study including “Neutral Electrolyzed Water”, “M22” organic disinfectant solution, Superoxy Food Wash disinfectant, Hydrogen Peroxide, Clorox Germicidal Bleach and Clidox-S. The effectiveness of these disinfectants was studied against various subtypes of avian influenza virus (AIV). The virus-disinfectant mixtures were prepared in serial dilutions of each disinfectant with a constant virus titer and incubated at ambient temperature in different time intervals for virus inactivation. The virus inactivation results were determined by virus recovery in embryonating chicken eggs. Among the six different kinds of nonmetallic disinfectants obtained for this research project, Neutral Electrolyzed Water, “M22” solution, Clorox Germicidal Bleach and Clidox-S were effectively inactivated AIV with appropriate working dilutions and reaction times. Superoxy Food Wash disinfectant and Hydrogen Peroxide were found having limited effect on virus inactivation with extended exposure times of more than 2 hours. These research findings provide scientific data to poultry industry with guidelines to select and use non-metallic organic disinfectants for poultry flock sanitation and disinfection to effectively prevent and control of avian influenza outbreaks.
基金supported by grants from NIH CA-125707 NSF CBET-0729091 (C D ),as well as NIH AI-065566 (A A )
文摘Introduction Vascular endothelial (VE)-cadherin is localized to the endothelial borders and the adherens junctions,which are regulated by changes in mitogen activated protein kinases (MAPK),GTPases,and intracellular calcium. We previously
基金supported by the startup research grant of the Pennsylvania State University(S.V.K.)
文摘Objective:To carry out the genetic characterization and evolutionary analysis of three avian orthoavulavirus 1(AOAV-1)isolates from poultry workers with respiratory symptoms.Methods:Using Illumina Mi Seq,whole-genome sequencing was carried out to assess the evolutionary dynamics of three AOAV-1 isolates.A phylogenetic and comparative analysis of all coding genes was done using bioinformatics tools.Results:Phylogenetic analysis and genetic distance estimation suggested a close relationship among human-and avian-originated velogenic strains of genotypeⅩⅢ,sub-genotypeⅩⅢ.2.1.Several substitutions in the significant structural and biological motifs were exclusively identified in the human-originated strains.Conclusions:To our knowledge,this is the first report of a velogenic AOAV-1 isolate from natural infection of the human upper respiratory tract.Our findings highlight the evolution and zoonotic potential of velogenic AOAV-1 in a disease endemic setting.
文摘Whenever there is no adequate DNA replication <em>in vitro</em>, there are alternatives strategies to insert a piece of DNA into a convenient replicon such as small plasmids and bacteriophages. These are called vectors or cloning vehicles. These days, there is a high demand to manufacture recombinant and nanobodies which are required in biomedical research and for therapeutic and diagnostic purposes. In order to do so, <em>E. coli</em>, insect cells, or mammalian cells have been used to express and purify protein for nanobody production. This paper explains the experimental trials on the cloning of the Nanobody cDNA mock-up in pHEN6c plasmid vector from the subcultured <em>E. coli</em> sample taken from the lab. The concentration and purity of DNA plasmid were evaluated by UV spectrophotometer and agarose gel electrophoresis following plasmid DNA Purification from <em>E. coli</em> by alkaline lysis. Based on this, the concentration of the isolated pHEN6c plasmid DNA was found 44.7 ng/μl or 0.0447 μg/μl. Whereas, the purity at absorbance (A260/A280) was 0.893/0.501 = 1.78. Moreover, its yield was 2.235 μg. In addition, its transformation efficiency was 21.68 μg/μl. On the other hand, the molecular weight of the Nanobody and vector were 569 and 2717 respectively. Generally, most of the protocols used to clone a fragment of DNA, might not work very well with PCR products.
文摘Rottweilers are predisposed to eosinophilic diseases, including hypereosinophilic syndrome. The immunopathogenesis of idiopathic eosinophilia is poorly characterised in dogs and man. Studies in people have suggested cytokines, particularly interleukin (IL)-5, play a role in instigating and perpetuating eosinophilia. This study sought to establish whether differences in gene expression, and concentration of selected, cytokines and chemokines were associated with eosinophilia in Rottweilers. Quantitative real-time reverse transcriptase polymerase chain reaction (qRT-PCR) assays were used to quantify messenger ribonucleic acid (mRNA) encoding cytokines IL-4, -5, -10, -12p19, -12p35, -12p40, -18, interferon gamma (IFN-γ) and chemokines eotaxin-2 and -3 from peripheral blood mononuclear cell (PMBC) samples obtained from healthy dogs (breeds other than Rottweiler) with normal eosinophil blood counts (n = 5) and Rottweilers with normal (n = 6), mildly increased (n = 7) and high (n = 3) eosinophil blood counts. Quantification of plasma IFN-γ and IL-5 was performed using commercially available canine-specific enzyme-linked immunosorbent assays ELISAs. Cytokine mRNA was measurable in all samples, although eotaxin-2 and -3 were not detected. No significant differences in gene expression of any cytokine were found between groups (based on eosinophil count or breed). No significant difference in plasma IL-5 or IFN-γ concentration was present between groups. In conclusion, there were no significant differences in cytokine mRNA profiles or plasma IL-5 and IFN-γ levels between Rottweilers with increased eosinophil counts and Rottweiler and non-Rottweiler dogs with normal eosinophil counts.
文摘Avian influenza (AI) virology surveillance is the most important method to monitor AI virus (AIV) in poultry so as to effectively prevent and control AI outbreaks. Monoclonal antibodies (MAb)-based assays are highly sensitive and specific for AIV detection, and much practical and economic for test-in-field or onsite. Many such assays have been developed and are still in developing since the H5N1 highly pathogenic AI (HPAI) outbreaks occurred in South East Asia in 2003. A MAb-based dot-enzyme-linked immunosorbent assay (ELISA) has been developed in our lab during late 1990s and early 2000s. Meanwhile, AIV H7 and H5 subtype specific-MAbs have been successfully developed in our laboratory to enhance the Dot-ELISA and other MAb-based assays for AIV detection. Production and purification of the H7 and H5 MAbs were made to provide essential reagents for Dot-ELISA and other immunoassays, and the current development of a novel Biosensor technique for rapid detection of AIV from clinical and field specimens.
文摘Escherichia coli O157:H7 is a human pathogen that was first identified from a foodborne outbreak in 1982, and in the 25 years that followed, many new strains were identified and emerged in numerous outbreaks of human disease. Extensive research has been conducted to identify virulence factor genes involved in the pathogenesis of E. coli O157:H7 and many genome sequences of E. coli O157:H7 strains have become available to the scientific community. Here, we provide a comprehensive overview of the research that has been conducted over the first 25 years to identify 394 known or putative virulence factor genes present in the genomes of E. coli O157:H7 strains. Finally, an examination of the conservation of these 394 virulence factor genes across additional genomes of E. coli O157:H7 is provided which summarizes the first 25 years and 13 genomes of this human pathogen.
基金Supported by the Programma Ricerca Budget prestazioni Eurac 2017 of the Province of Bolzano,Italy
文摘The bacterium Helicobacter pylori(H.pylori)infects the stomachs of approximately 50%of all humans.With its universal occurrence,high infectivity and virulence properties it is considered as one of the most severe global burdens of modern humankind.It has accompanied humans for many thousands of years,and due to its high genetic variability and vertical transmission,its population genetics reflects the history of human migrations.However,especially complex demographic events such as the colonisation of Europe cannot be resolved with population genetic analysis of modern H.pylori strains alone.This is best exemplified with the reconstruction of the 5300-year-old H.pylori genome of the Iceman,a European Copper Age mummy.Our analysis provided precious insights into the ancestry and evolution of the pathogen and underlined the high complexity of ancient European population history.In this review we will provide an overview on the molecular analysis of H.pylori in mummified human remains that were done so far and we will outline methodological advancements in the field of ancient DNA research that support the reconstruction and authentication of ancient H.pylori genome sequences.
文摘Increasing numbers of amphibian species require conservation breeding programs for their survival.A major challenge is the efficient rearing of tadpoles,many of which require complex habitats and specialised diets.Aquatic tadpoles of the West Australian frog Litoria moorei were kept at low density(1 tadpole per 1.95 litres water) in aquaria at 25℃.Fed on a staple diet of boiled lettuce and leaf litter,group of diets were supplemented with either control,Wardley Premium Spirulina Discs,Sera~(TM) GVG-mix tropical fish food,or a combination of Wardley Premium Spirulina discs and Sera~(TM) GVG-mix fish food.There was a relatively high loss(i.e.,found dead,euthanized due to scoliosis,or not found) of tadpoles fed with the lettuce/leaf litter alone,but this was increased significantly when supplemented with Wardley Premium Spirulina discs,either alone or with Sera~(TM) GVG-mix fish food,and Sera~(TM) GVG fish food alone.However,the survived tadpoles fed on the three supplements were all heavier after three weeks and at metamorphosis than those fed with lettuce/leaf litter alone,and reached metamorphosis quicker.It is concluded that any benefit of the food supplements in terms of increasing the rate of growth and development of the tadpoles is outweighed by greater mortality.There is now a need for the efficient rearing of tadpoles,many from novel species that need complex habitats.Further studies of diet are required due to the current conservation crisis of amphibians.
基金supported by National Natural Science Foundation of China(42322710,41977364)National Key Research and Development Program of China(2021YFC3200105)+2 种基金the Joint Research Project for the Yangtze River Conservation(Phase II),China(NO.2022-LHYJ-02-0101).Prof.Giesy was supported by the“High Level Foreign Experts”program(#GDT20143200016)funded by the State Administration of Foreign Experts Affairs,the P.R.China to Nanjing University and the Einstein Professor Program of the Chinese Academy of Sciencessupported by the Canada Research Chair program and a Distinguished Visiting Professorship in the Department of Environmental Sciences at Baylor University,Waco,Texas,USA.
文摘Lake ecosystems confront escalating challenges to their stability and resilience,most intuitively leading to biodiversity loss,necessitating effective preservation strategies to safeguard aquatic environments.However,the complexity of ecological processes governing lake biodiversity under multi-stressor interactions remains an ongoing concern,primarily due to insufficient long-term bioindicator data,particularly concerning macroinvertebrate biodiversity.Here we utilize a unique,continuous,and in situ biomonitoring dataset spanning from 2011 to 2019 to investigate the spatio-temporal variation of macroinvertebrate communities.We assess the impact of four crucial environmental parameters on Lake Dongting and Lake Taihu,i.e.,water quality,hydrology,climate change,and land use.These two systems are representative of lakes with Yangtze-connected and disconnected subtropical floodplains in China.We find an alarming trend of declining taxonomic and functional diversities among macroinvertebrate communities despite improvements in water quality.Primary contributing factors to this decline include persistent anthropogenic pressures,particularly alterations in human land use around the lakes,including intensified nutrient loads and reduced habitat heterogeneity.Notably,river-lake connectivity is pivotal in shaping differential responses to multiple stressors.Our results highlight a strong correlation between biodiversity alterations and land use within a 2e5 km radius and 0.05e2.5 km from the shorelines of Lakes Dongting and Taihu,respectively.These findings highlight the importance of implementing land buffer zones with specific spatial scales to enhance taxonomic and functional diversity,securing essential ecosystem services and enhancing the resilience of crucial lake ecosystems.
