Background: The success of cuckoo parasitism is thought to depend largely on the extent of egg matching between cuckoo and host eggs, since poor-matching cuckoo egg would lead to more frequent egg rejection by the hos...Background: The success of cuckoo parasitism is thought to depend largely on the extent of egg matching between cuckoo and host eggs, since poor-matching cuckoo egg would lead to more frequent egg rejection by the host. In this study, we investigated how egg-spot matching between the Common Cuckoo(Cuculus canorus) and its host, the Oriental Reed Warbler(Acrocephalus orientalis) is affected by the local parasitism rate, nest availability in breeding synchronization and egg rejection.Methods: We used the paired design of parasitized and their nearest non-parasitized nests where breeding occurred simultaneously to compare egg-spot matching. The image analysis was used to compare four eggshell pattern variables, namely spot size, density, coverage on the different areas of egg surface, and the distribution on the whole egg surface. Egg recognition experiments were conducted to test the effect of egg spots on egg rejection by the host.Results: Our results show that much better matching in almost all spot parameters tested on the side of the egg and the spot distribution on the whole egg occurred in parasitized nests than in non-parasitized nests. Matching of spot density between cuckoo and host eggs in parasitized nests increased with the synchronization between temporal availability of nests and the egg-laying period of female cuckoos. Egg recognition experiments in which the warbler eggs were deliberately painted with extra spots led to a significantly higher egg rejection rate(78.3%) than of unpainted eggs.Conclusion: Our data suggest that both the high temporal encounter rate between cuckoo and warbler nests as well as the high egg rejection ability of the host are important factors for egg-spot matching of the cuckoos.展开更多
Background:Red-winged Blackbirds(Agelaius phoeniceus),hereafter red-wings,are much less frequently parasitized by Brown-headed Cowbirds(Molothrus ater)in eastern North America than in central North America and had not...Background:Red-winged Blackbirds(Agelaius phoeniceus),hereafter red-wings,are much less frequently parasitized by Brown-headed Cowbirds(Molothrus ater)in eastern North America than in central North America and had not been recorded as hosts in our study area in southeastern Pennsylvania.Although hosts of Old World cuckoos(Cuculidae)often show geographic variation in egg rejection behavior,cowbird hosts typically exhibit uniform responses of all acceptance or all rejection of cowbird eggs.Thus,geographic variation in cowbird parasitism frequencies might reflect a different behavioral response to parasitism by hosts where only some populations reject parasitism.In this study,we tested whether egg rejection behavior may explain the lack of parasitism observed in our eastern red-wing population,which may provide insight into low parasitism levels across eastern North America.Methods:We parasitized red-wing nests with model cowbird eggs to determine their response to parasitism.Nests were tested across three nest stages and compared to control nests with no manipulations.Because rejection differed significantly by stage,we compared responses separately for each nest stage.We also monitored other songbird nests to identify parasitism frequencies on all potential hosts.Results:Red-wings showed significantly more rejections during the building stage,but not for the laying and incubation stages.Rejections during nest building involved mostly egg burials,which likely represent a continuation of the nest building process rather than true rejection of the cowbird egg.Excluding these responses,red-wings rejected 15%of cowbird eggs,which is similar to rejection levels from other studies and populations.The overall parasitism frequency on 11 species surveyed in our study area was only 7.4%.Conclusions:Egg rejection behavior does not explain the lack of parasitism on red-wings in our eastern population.Alternatively,we suggest that cowbird preference for other hosts and the low abundance of cowbirds in the east might explain the lack of parasitism.Future research should also explore cowbird and host density and the makeup of the host community to explain the low levels of parasitism on red-wings across eastern North America because egg rejection alone is unlikely to explain this broad geographic trend.展开更多
Living and/or non-living animal models are often used as stimuli to observe the behavioral responses of the target animals.In the past,parasites,predators,and harmless controls have been used to test host anti-parasit...Living and/or non-living animal models are often used as stimuli to observe the behavioral responses of the target animals.In the past,parasites,predators,and harmless controls have been used to test host anti-parasitism defense behavior,and their taxidermy specimens have been widely used as a set of standard methods for the study of avian brood parasitism.In recent years,with the rapid development of 3D-printing technology,3D-printed bird models are expected to be applied as a standard method in the study of avian brood parasitism.To evaluate the use of 3D-printed models,this study tests the reaction of Oriental Reed Warbler(Acrocephalus orientalis)towards predators,parasites,or controls,and compares the reaction among different nest intruders and between taxidermy specimens and 3D-printed animal models.It was found that the Oriental Reed Warbler responded most aggressively to the parasite,followed by predator,and finally the control;the results were consistent between the reaction to taxidermy specimens and 3D-printed animal models,indicating that 3D-printed models could serve as a substitute for taxidermy specimens.We propose a series of advantages of using 3D-printed models and suggest them to be a standard method for widespread use in future studies of avian brood parasitism.展开更多
Introduction: Intestinal parasitism has been a challenge to overcome for the Mexican deworming campaign and this study determined the prevalence of these infections in schoolchildren treated with albendazole in Northw...Introduction: Intestinal parasitism has been a challenge to overcome for the Mexican deworming campaign and this study determined the prevalence of these infections in schoolchildren treated with albendazole in Northwestern Mexico. Methods: Study sites in marginal conditions, with gastrointestinal infections and albendazole intervention were selected. The Faust and Kato Katz techniques were used to identify the parasites spp. and the NCSS software was used for statistical analysis. Results: A total of 450, 389 and 364 schoolchildren participated in 2005, 2006, and 2007 respectively during this study. The mean age was 7.9 (±1.3). The estimated prevalences were of 42%, 30% and 37% for protozoa infections, and 11%, 12% and 11% for helminth infections in 2005, 2006 and 2007 respectively. Conclusion: The education strategies should be integrated into the Mexican deworming campaign.展开更多
The Plaintive Cuckoo(Cacomantis merulinus) is a widespread brood parasite in Asia, but no data on host species utilization in Bangladesh exist. By searching for nests of all possible host species of the Plaintive Cuck...The Plaintive Cuckoo(Cacomantis merulinus) is a widespread brood parasite in Asia, but no data on host species utilization in Bangladesh exist. By searching for nests of all possible host species of the Plaintive Cuckoo at Jahangirnagar university campus, north of Dhaka, we were able to determine which hosts were used in this area. We found that the Common Tailorbird(Orthotomus sutorius) was the only potential host used by Plaintive Cuckoos, and parasitism rate was rather high(31.3 %, n = 16). However, both host and cuckoo breeding success was poor(0 %, n = 16) due to frequent nest predation. Details on host and cuckoo egg appearance are provided. Our findings indicate that Common Tailorbirds are common hosts of the Plaintive Cuckoo in Central Bangladesh.展开更多
The reniform nematode (RN), Rotylenchulus reniformis, is an agriculturally important pest with a broad host range that results in a large economic impact in tropical, subtropical and in warm temperate zones. In an ini...The reniform nematode (RN), Rotylenchulus reniformis, is an agriculturally important pest with a broad host range that results in a large economic impact in tropical, subtropical and in warm temperate zones. In an initial effort to understand the transcriptome and gene expression in RN, we present EST results that reveal numerous putative parasitism-related genes some of which play roles in plant cell wall modification. The characterized contigs included 8362 (40.6%) matches to unique proteins. Coding contigs predicted were 10,656 (51.7%) or 3079 (14.9%), that was similar to those identified in Brugia malayi and Caenorhabditis elegans as reference organisms respectively. Specific transcripts studied in more detail include putative plant parasitism genes, prominent among them were several plant cell wall modification genes. Contigs matching 14 parasitism genes found in sedentary endoparasitic nematodes included expansins, hexosaminidase, glycosyl hydrolases family, 14-3-3 protein, xylanases, glutathione peroxidase, pectate lyase, β-1,4-endoglucanase, major sperm protein, aminopeptidase, c-type lectin, chitin synthase, FMR famide-like peptide, and calreticulin. These genes function in suppression of host defenses and development of feeding sites.展开更多
正We are pleased to publish the second special issue on avian brood parasitism and to be responsible guest editors for the two special issues of Chinese Birds (Vol. 3, No. 4, 2012 and Vol. 4, No. 1, 2013), entitled &q...正We are pleased to publish the second special issue on avian brood parasitism and to be responsible guest editors for the two special issues of Chinese Birds (Vol. 3, No. 4, 2012 and Vol. 4, No. 1, 2013), entitled "Avian Brood Parasitism - A Growing Research Area in Behavioral Ecology". The first issue was published in December 2012. The goal of the two special issues is to publish accumulated knowledge and some of the recent developments展开更多
Tea tortrix, Homona coffearia Nietner (Lepidoptera: Tortricidae), is a seasonal pest of tea in Sri Lanka. Though it is active in dry weather, it is observed that populations do occur in wet weather causing serious dam...Tea tortrix, Homona coffearia Nietner (Lepidoptera: Tortricidae), is a seasonal pest of tea in Sri Lanka. Though it is active in dry weather, it is observed that populations do occur in wet weather causing serious damage to tea. The parasite, Macrocentrus homonae Nixon (Hymenoptera: Braconidae), controls the tortrix populations, but the efficiency of Macrocentrus has been reduced on account of hyperparasites in recent times. Level of hyperparasitism was studied in some tea tortrix prone areas in the up country region to study how this affected the tortrix populations during wet weather. The hyperparasitism varied during the study period of which average values observed ranged from 35% to 52% in the plantations studied. A negative linear relationship was observed between the average number of parasite cocoons in a cocoon mass and the percentage hyperparasitism. Three generations of tortrix were evident during the study period of May to November 2005. It is observed that tortrix populations do occur in dry and wet weather, and that hyperparasitism has been identified as the major cause affecting the efficient control of tortrix by the parasite. Possibilities of tea tortrix control in wet weather are discussed.展开更多
正Invited participants on the 3rd International Symposium on Avian Brood Parasitism, sponsored by Hainan Normal University (HNU), China, Norwegian University of Science and Technology (NTNU), Norway, the Research Coun...正Invited participants on the 3rd International Symposium on Avian Brood Parasitism, sponsored by Hainan Normal University (HNU), China, Norwegian University of Science and Technology (NTNU), Norway, the Research Council of Norway, and China Ornithological Society (COS).展开更多
Objective:To ascertain the level of intestinal parasites vis-a-vis the quality of housing and water supply,and sanitary conditions among the people of Kuraje village in Zamfara state. Methods:The study was cross secti...Objective:To ascertain the level of intestinal parasites vis-a-vis the quality of housing and water supply,and sanitary conditions among the people of Kuraje village in Zamfara state. Methods:The study was cross sectional in nature.Individual households were selected using systematic random sampling methods and pre-tested questionnaires were administered to all the members of each household.Stool samples were collected and processed using standard laboratory procedures.Housing conditions,sources of water and sanitary conditions of the households were also inspected.Results were analysed using Epi Info 2006 model.Results: The prevalence of intestinal parasites was 67.0%(347/519).72.3%(251/347),17.0%(59/347),and 10.7%(37/347) had one,two and three or more parasites,respectively.The associated factors with intestinal parasites were poor housing and sanitary conditions,lack of potable water and illiteracy.The commonest parasites encountered were hookworm(22.0%),Ascaris lumbricoides (18.5%),and Strongyloides stercoralis(15.6%) while the least common was Enterobius vermicularis (1.6%).Others were Giardia lamblia(5.7%),Hymenolepsis nana(5.0%),Trichuris trichiura(8.8%), Entamoeba histolytica(14.4%) and Schistosoma mansoni(8.4%).Conclusions:The infection rate of intestinal parasites in Kuraje village is high.More efforts should be intensified towards improvement in sanitary and housing standards,supply of potable water and institution of a more comprehensive literacy programme for the people of the community.展开更多
Captivity of wild animals and restriction of their movement can lead to stress, resulting in suppressed immune response and reduced disease resistance ability. Wild animals in zoological gardens can predominately affe...Captivity of wild animals and restriction of their movement can lead to stress, resulting in suppressed immune response and reduced disease resistance ability. Wild animals in zoological gardens can predominately affected by various gastro-intestinal parasites. This study was therefore, conducted to determine occurrence, identify types and assess seasonal variation of gastrointestinal parasites in captive animals at the Zoological garden of Haramaya University. The study involved a retrospective investigation of zoo records and fecal examinations. Twenty two fecal samples were collected in December, 2013 from all the animals in the garden and examined using concentration and fecal culture techniques. Sampling was repeated after four months in April, 2014 to assess seasonal variations of the parasites. The result from the retrospective study showed death of 21 animals in the last five years. Fecal examination confirmed presence of gastrointestinal parasites with an overall mean prevalence rate of 73.8%. A total of 9 parasite taxa were identified of which 6 (66.67%) and 4 (33.33%) were helminths and protozoa respectively. No Cestode and Trematode species were recovered. <i>Trichuris spp.</i>, <i>Toxocara spp.</i>, <i>Strongyloides spp.</i>, <i>Toxascaris leonine</i>, <i>Passalurus ambiguous</i> and <i>Ascaridia spp.</i> were the helminth parasites observed in the garden. <i>Entamoeba spp.</i>, <i>Isospora spp.</i> and <i>Eimeria spp.</i> were the protozoan parasites encountered. No remarkable seasonal variation in parasitic infection was noticed in the garden. The study revealed occurrence of gastrointestinal parasites in the zoological garden, most of which are zoonotic and hence future studies are needed to determine risks of cross-transmission.展开更多
The interactions between avian brood parasites and their hosts provide an informative and easy-to-handle system for studying coevolution.Avian brood parasitism reduces the reproductive success of hosts,and thus,hosts ...The interactions between avian brood parasites and their hosts provide an informative and easy-to-handle system for studying coevolution.Avian brood parasitism reduces the reproductive success of hosts,and thus,hosts have evolved anti-parasitic strategies,such as rejecting parasitic eggs and adopting aggressive nest defense strategies,to avoid the cost brought on by brood parasitism.To test whether host anti-parasitic strategies are adjusted with the risk of being parasitized when the breeding seasons of brood parasites and hosts are not synchronous,we conducted a field experiment assessing nest defense and egg recognition behaviors of the Isabelline Shrike(Lanius isabellinus),a host of the Common Cuckoo(Cuculus canorus).In the local area,the host Isabelline Shrike begins to breed in April,whereas the summer migratory Common Cuckoo migrates to the local area in May and begins to lay parasitic eggs.Results showed that nest defense behaviors of the Isabelline Shrike increases significantly after cuckoo arrival,showing higher aggressiveness to cuckoo dummies,with no significant difference in attack rates among cuckoo,sparrowhawk and dove dummies,but their egg rejection did not change significantly.These results imply that Isabelline Shrikes may adjust their nest defense behavior,but not egg rejection behavior,with seasonality.展开更多
Coevolutionary arms races between brood parasites and hosts provide tractable systems for understanding antagonistic coevolution in nature;however,little is known about the fate of frontline antiparasite defenses when...Coevolutionary arms races between brood parasites and hosts provide tractable systems for understanding antagonistic coevolution in nature;however,little is known about the fate of frontline antiparasite defenses when the host“wins”the coevolutionary arms race.By recreating bygone species interactions,using artificial parasitism experiments,lingering defensive behaviors that evolved in the context of parasitism can be understood and may even be used to identify the unknown agent of parasitism past.Here we present the first study of this type by evaluating lingering“frontline”nest defenses that have evolved to prevent egg laying in a former brood parasite host.The Australian reed warbler Acrocephalus australis is currently not parasitized but is known to exhibit fine-tuned egg discrimination—a defensive behavior indicative of a past brood parasite–host arms race and common in closely related parasitized species.Here,using 3D-printed models of adult brood parasites,we examined whether the Australian reed warbler also exhibits frontline defenses to adult brood parasites,and whether we could use these defenses to identify the warbler’s“ghost of parasitism past.”Our findings provide evidence that the Australian reed warbler readily engages in frontline defenses that are considered adaptive specifically in the context of brood parasitism.However,individuals were unable to discriminate between adults of different brood parasite species at their nest.Overall,our results demonstrate that despite a relaxation in selection,defenses against brood parasitism can be maintained across multiple stages of the host’s nesting cycle,and further suggest that,in accordance with previous findings,that learning may be important for fine-tuning frontline defense.展开更多
A fun dame ntal question in biology is how diversity evolves and why some clades are more diverse than others.Phenotypic diversity has often been shown to result from morphological adaptation to different habitats.The...A fun dame ntal question in biology is how diversity evolves and why some clades are more diverse than others.Phenotypic diversity has often been shown to result from morphological adaptation to different habitats.The role of behavioral interactions as a driver of broadscale phenotypic diversity has received comparatively less attention.Behavioral interactions,however,are a key agent of natural selection.Antagonistic behavioral interactions with predators or with parasites can have significant fitness consequences,and hence act as strong evolutionary forces on the phe no type of species,ultimately gen erating diversity betwee n species of both victims and exploiters.Avian obligate brood parasites lay their eggs in the nests of other species,their hosts,and this behavioral interaction between hosts and parasites is often considered one of the best examples of coevolution in the natural world.In this review,we use the coevolution between brood parasites and their hosts to illustrate the potential of behavioral interactions to drive evolution of phenotypic diversity at different taxonomic scales.We provide a bridge between behavioral ecology and macroevolution by describing how this interaction has increased avian phenotypic diversity not only in the brood parasitic clades but also in their hosts.展开更多
As solitary nymphal parasitoids of Pamtrioza sinica,the ectoparasitoid Tamarixia lyciumi and the endoparasitoid Psyllaephagus arenarius act as effective biocontrol agents.Thus,it is necessary to facilitate mass produc...As solitary nymphal parasitoids of Pamtrioza sinica,the ectoparasitoid Tamarixia lyciumi and the endoparasitoid Psyllaephagus arenarius act as effective biocontrol agents.Thus,it is necessary to facilitate mass productions of both species.Despite showing an excellent parasitic ability,Ps.arenarius is often trapped fatally inside 5th-instar nymphs of Pa.sinica due to strong host immunity.To improve the emergence rate of Ps.arenarius,we evaluated whether Ps.arenarius could utilize T.lyciumi venom via multiparasitism,so the parasitism characteristics of both species were examined between separate-existence(monoparasitism only)and co-existence(mono-and multiparasitism)systems.Further,the parasitism characteristics of Ps.arenarius on venom-injected hosts with/without T.lyciumi eggs were tested to further identify the facilitator.The results showed the parasitism rate of T.lyciumi was increased while that of Ps.arenarius did not change from separate-existence to co-existence systems.The intrinsic performances of two species in monoparasitism did not differ between separate-and co-existence systems.From monoparasitism(separate-existence)to multiparasitism(co-existence),no differences were detected in the intrinsic performances of T.lyciumi,but those of Ps.arenarius were greatly improved.After T.lyciumi venom injection,the parasitism characteristics of Ps.arenarius did not differ between venom-injected hosts with T.lyciumi eggs and those without,further indicating Ps.arenarius benefited from the venom of T.lyciumi females rather than T.lyciumi egg/larval secretions.Instead of negative effects,multiparasitism with ectoparasitoids improves endoparasitoids due to ectoparasitic venom.The study increases host resource utilization and provides creative ways for mass production of endoparasitoids.展开更多
The harmonics that appear in the squirrel cage asynchronous machine have been discussed in great detail in the literature for a long time. However, the systematization of the phenomenon is still pending, so we made an...The harmonics that appear in the squirrel cage asynchronous machine have been discussed in great detail in the literature for a long time. However, the systematization of the phenomenon is still pending, so we made an attempt to fill this gap in the previous parts of our study by elaborating formulas for calculation of parasitic torques. It was a general demand among those who work in this field towards the author to verify his formulas with measurements. In the literature, it seems,only one detailed, purposeful series of measurements has been published so far, the purpose of which was to investigate the effect of the number of rotor slots on the torque-speed characteristic curve of the machine. The main goal of this study is to verify the correctness of the formulas by comparing them with the referred series of measurements. Relying on this, the expected synchronous parasitic torques were developed for the frequently used rotor slot numbers-as a design guide for the engineer.Thus, together with our complete table for radial magnetic pull published in our previous work, the designer has all the principles, data and formulas available for the right number of rotor slots for his given machine and for the drive system. This brings this series of papers to an end.展开更多
Based on the attributes of nonflammability,environmental benignity,and cost-effectiveness of aqueous electrolytes,as well as the favorable compatibility of zinc metal with them,aqueous zinc ions batteries(AZIBs)become...Based on the attributes of nonflammability,environmental benignity,and cost-effectiveness of aqueous electrolytes,as well as the favorable compatibility of zinc metal with them,aqueous zinc ions batteries(AZIBs)become the leading energy storage candidate to meet the requirements of safety and low cost.Yet,aqueous electrolytes,acting as a double-edged sword,also play a negative role by directly or indirectly causing various parasitic reactions at the zinc anode side.These reactions include hydrogen evolution reaction,passivation,and dendrites,resulting in poor Coulombic efficiency and short lifespan of AZIBs.A comprehensive review of aqueous electrolytes chemistry,zinc chemistry,mechanism and chemistry of parasitic reactions,and their relationship is lacking.Moreover,the understanding of strategies for suppressing parasitic reactions from an electrochemical perspective is not profound enough.In this review,firstly,the chemistry of electrolytes,zinc anodes,and parasitic reactions and their relationship in AZIBs are deeply disclosed.Subsequently,the strategies for suppressing parasitic reactions from the perspective of enhancing the inherent thermodynamic stability of electrolytes and anodes,and lowering the dynamics of parasitic reactions at Zn/electrolyte interfaces are reviewed.Lastly,the perspectives on the future development direction of aqueous electrolytes,zinc anodes,and Zn/electrolyte interfaces are presented.展开更多
BACKGROUND Ankylosing spondylitis(AS)is a chronic immune-mediated inflammatory disease.The prevailing theory links AS onset to infections in susceptible individuals.Furthermore,infections may impair the immune respons...BACKGROUND Ankylosing spondylitis(AS)is a chronic immune-mediated inflammatory disease.The prevailing theory links AS onset to infections in susceptible individuals.Furthermore,infections may impair the immune responses.Numerous studies have investigated links between AS and various infections-bacterial,viral,fungal,and other microorganism infections.However,limited attention has been given to the association between AS and Clonorchis sinensis(C.sinensis)infection.CASE SUMMARY A 27-year-old male with a 10-yr history of AS presented to our hospital with inflammatory lower back pain as the primary manifestation.Ten years ago,the patient had achieved a stable condition after treatment with biological agents.However,he experienced a recurrence of lumbosacral pain with an unexplained cause 10 d before hospital admission.A lumbosacral magnetic resonance imaging(MRI)scan revealed bone marrow edema in the left sacroiliac joint,and laboratory indicators were elevated.Moreover,the presence of C.sinensis eggs was detected in the stool.The patient was prescribed praziquantel,resulting in the disap-pearance of C.sinensis eggs in subsequent routine stool tests and relief from lumbosacral pain.A follow-up MRI scan performed after 4 months revealed a reduction in bone marrow edema around the left sacroiliac joint.CONCLUSION C.sinensis infections could potentially trigger the exacerbation of AS.Clinicians should pay attention to investigating the presence of infections.INTRODUCTION Ankylosing spondylitis(AS)is a chronic inflammatory and rheumatic disease resulting from an imbalance between innate and acquired immune responses[1].While it can affect any part of the spine,its primary symptoms are persistent back pain and stiffness in the lower back and pelvis.The prevalence of AS per 10000 individuals is 23.8 in Europe,31.9 in North America,16.7 in Asia,10.2 in Latin America,and 7.4 in Africa[2].Infections commonly occur in the first 3 months and may act as potential triggers for the first symptoms of AS,often manifesting as gastrointestinal,urinary tract,and respiratory infections of microbiological origin[3,4].Clonorchis sinensis(C.sinensis)infection is a severe parasitic disease affecting millions globally,especially prevalent in China,South Korea,the Far East of Russia,and Vietnam,with an estimated 15 million cases[5].Transmission occurs through the consumption of undercooked freshwater fish containing metacercariae.Adult C.sinensis parasites then establish themselves within the human hepatobiliary system[6].C.sinensis infection triggers the activation of sphingosine 1-phosphate receptor 2,leading to the injury and fibrosis of the hepatobiliary[7].Recent research in a rat model found that C.sinensis infection increases the risk of hepatocellular carcinoma by stimulating hepatic progenitor cell proliferation[8].Complications of C.sinensis infection include cholestasis,cholangitis,biliary system fibrosis,and in severe cases,the development of cholangiocarcinoma[9].Consequently,the primary preventive measure is to abstain from consuming raw or undercooked freshwater fish.Praziquantel is the recommended and effective treatment for this infection[10].While there is existing literature on the coexistence of AS and parasitic infections,there is limited research specifically addressing the simultaneous presence of AS and C.sinensis infection.This case report details a rare scenario of AS coexisting with C.sinensis infection,underscoring the potential impact of C.sinensis infection on AS disease activity.展开更多
Orobanchaceae is the largest family of parasiticplants,containing autotrophic and parasiticplants with all degrees of parasitism.This makes it byfar the best family for studying the origin and evolution of plant paras...Orobanchaceae is the largest family of parasiticplants,containing autotrophic and parasiticplants with all degrees of parasitism.This makes it byfar the best family for studying the origin and evolution of plant parasitism.Here we provide three high-quality genomes of orobanchaceous plants,the autotrophic Lindenbergia luchunensis and the holoparasitic plants Phelipanche aegyptiaca and Orobanche cumana.Phylogenomic analysis of these three genomes together with those previously published and the transcriptomes of other orobanchaceous species createda robust phylogeneticframework forOrobanchaceae.We found that an ancient whole-genome duplication(WGD;about 73.48million years ago),which occurred earlierthan theoriginof Orobanchaceae,mighthave contributed totheemergence of parasitism.However,no WGD events occurred in any lineage of orobanchaceous parasites except for Striga after divergence from their autotrophic common ancestor,suggesting that,in contrast with previous speculations,WGD is not associated with the emergence of holoparasitism.We detected evident convergent gene loss in all parasites within Orobanchaceae and between Orobanchaceae and dodder Cuscuta australis.The gene families in the orobanchaceous parasites showed a clear pattern of recent gains and expansions.The expanded gene families are enriched in functions related to the development of the haustorium,suggesting that recent gene family expansions may have facilitated the adaptation of orobanchaceous parasites to different hosts.This study illustrates a stepwise pattern in the evolution of parasitism in the orobanchaceous parasites and will facilitate future studieson parasitism and the control of parasitic plants in agriculture.展开更多
Background:Intestinal parasitic infections(IPIs)among indigenous people have been widely documented in Malaysia,however,the prevalence of these infections remains high.In the past,most studies have focused on specific...Background:Intestinal parasitic infections(IPIs)among indigenous people have been widely documented in Malaysia,however,the prevalence of these infections remains high.In the past,most studies have focused on specific species of parasites but polyparasitism has received limited attention.In addition,epidemiology studies on indigenous people tend to consider them as a homogenous group,whereas in reality different sub-ethnic groups have different cultural and living practices.Variations in living habits such as personal hygiene practices may predispose different groups to different parasitic infections.To better understand prevalence and risk factors of intestinal parasitism among different sub-ethnic groups,the present study was conducted among two sub-ethnic groups of indigenous people(Temuan and Mah Meri)residing in Selangor state,Malaysia.Methods:A cross-sectional study that focused on two distinct sub-ethnic groups was carried out from February to September 2014.Faecal samples were collected from 186 participants and examined using the formalin-ether sedimentation technique.A molecular approach was adopted to conduct a genetic characterisation of the parasites.Additionally,questionnaires were administered to obtain information on the demographics,socioeconomic backgrounds and behavioural risks relating to the participants,as well as information about their environments.Statistical analyses(i.e.binary and multivariate logistic regression analyses)were performed to measure risk factors.Results:For Temuan communities,trichuriasis(64.2%)was the most common infection found,preceding hookworm infection(34%),ascariasis(7.5%),giardiasis(14.2%)and amoebiasis(7.5%).As for the Mah Meri communities,trichuriasis(77.5%)prevailed over ascariasis(21.3%),hookworm(15%),giardiasis(7.5%)and amoebiasis(3.8%).Significant differences in proportions of trichuriasis,ascariasis and hookworm infections were observed between the Temuan and Mah Meri sub-ethnic groups.Polyparasitism was more common among the Temuan sub-ethnic group(41.5%)compared to the Mah Meri sub-ethnic group(32.5%),with the majority of participants harbouring two parasites concurrently(Temuan:33%,Mah Meri:20%).Trichuris trichiura and Ascaris lumbricoides co-infections were most prevalent(10%)among the Mah Meri communities,while a co-infection of T.trichiura with hookworm(19.8%)was most common among the Temuan communities.Multivariate analyses showed that being unemployed,having a large family and drinking unboiled water were found to be significantly associated with intestinal parasitism.Conclusion:The present study highlights substantial polyparasitism and risk factors for infections in the Temuan and Mah Meri sub-ethnic groups.The high prevalence of IPIs among these two sub-ethnic groups indicates that parasitic infections are important health issues in these communities.Hence,it is imperative to implement sound intervention strategies such as periodic preventive chemotherapy coupled with health education in order to reduce and eradicate these infections.展开更多
基金supported by the National Natural Science Foundation of China (Nos.31301888 and 31672316 to DL)the General Scientific Research Project of the Education Department of Liaoning Province (L2015196 to DL)the Open Fund of the Ministry of Education Key Laboratory for Biodiversity Sciences and Ecological Engineering, Beijing Normal University (K1401 to DL)
文摘Background: The success of cuckoo parasitism is thought to depend largely on the extent of egg matching between cuckoo and host eggs, since poor-matching cuckoo egg would lead to more frequent egg rejection by the host. In this study, we investigated how egg-spot matching between the Common Cuckoo(Cuculus canorus) and its host, the Oriental Reed Warbler(Acrocephalus orientalis) is affected by the local parasitism rate, nest availability in breeding synchronization and egg rejection.Methods: We used the paired design of parasitized and their nearest non-parasitized nests where breeding occurred simultaneously to compare egg-spot matching. The image analysis was used to compare four eggshell pattern variables, namely spot size, density, coverage on the different areas of egg surface, and the distribution on the whole egg surface. Egg recognition experiments were conducted to test the effect of egg spots on egg rejection by the host.Results: Our results show that much better matching in almost all spot parameters tested on the side of the egg and the spot distribution on the whole egg occurred in parasitized nests than in non-parasitized nests. Matching of spot density between cuckoo and host eggs in parasitized nests increased with the synchronization between temporal availability of nests and the egg-laying period of female cuckoos. Egg recognition experiments in which the warbler eggs were deliberately painted with extra spots led to a significantly higher egg rejection rate(78.3%) than of unpainted eggs.Conclusion: Our data suggest that both the high temporal encounter rate between cuckoo and warbler nests as well as the high egg rejection ability of the host are important factors for egg-spot matching of the cuckoos.
基金provided by a BEARS Grant and a Neag Undergraduate Research Grant from Kutztown University
文摘Background:Red-winged Blackbirds(Agelaius phoeniceus),hereafter red-wings,are much less frequently parasitized by Brown-headed Cowbirds(Molothrus ater)in eastern North America than in central North America and had not been recorded as hosts in our study area in southeastern Pennsylvania.Although hosts of Old World cuckoos(Cuculidae)often show geographic variation in egg rejection behavior,cowbird hosts typically exhibit uniform responses of all acceptance or all rejection of cowbird eggs.Thus,geographic variation in cowbird parasitism frequencies might reflect a different behavioral response to parasitism by hosts where only some populations reject parasitism.In this study,we tested whether egg rejection behavior may explain the lack of parasitism observed in our eastern red-wing population,which may provide insight into low parasitism levels across eastern North America.Methods:We parasitized red-wing nests with model cowbird eggs to determine their response to parasitism.Nests were tested across three nest stages and compared to control nests with no manipulations.Because rejection differed significantly by stage,we compared responses separately for each nest stage.We also monitored other songbird nests to identify parasitism frequencies on all potential hosts.Results:Red-wings showed significantly more rejections during the building stage,but not for the laying and incubation stages.Rejections during nest building involved mostly egg burials,which likely represent a continuation of the nest building process rather than true rejection of the cowbird egg.Excluding these responses,red-wings rejected 15%of cowbird eggs,which is similar to rejection levels from other studies and populations.The overall parasitism frequency on 11 species surveyed in our study area was only 7.4%.Conclusions:Egg rejection behavior does not explain the lack of parasitism on red-wings in our eastern population.Alternatively,we suggest that cowbird preference for other hosts and the low abundance of cowbirds in the east might explain the lack of parasitism.Future research should also explore cowbird and host density and the makeup of the host community to explain the low levels of parasitism on red-wings across eastern North America because egg rejection alone is unlikely to explain this broad geographic trend.
基金This study was supported by the Education Department of Hainan Province(HnjgY2022-12)Hainan Provincial Natural Science Foundation of China(320CXTD437 and 2019RC189)+1 种基金the National Natural Science Foundation of China(32260127 and 31672303)to CYthe Hainan Provincial Innovative Research Program for Graduates(Qhyb2021-55)to XC.
文摘Living and/or non-living animal models are often used as stimuli to observe the behavioral responses of the target animals.In the past,parasites,predators,and harmless controls have been used to test host anti-parasitism defense behavior,and their taxidermy specimens have been widely used as a set of standard methods for the study of avian brood parasitism.In recent years,with the rapid development of 3D-printing technology,3D-printed bird models are expected to be applied as a standard method in the study of avian brood parasitism.To evaluate the use of 3D-printed models,this study tests the reaction of Oriental Reed Warbler(Acrocephalus orientalis)towards predators,parasites,or controls,and compares the reaction among different nest intruders and between taxidermy specimens and 3D-printed animal models.It was found that the Oriental Reed Warbler responded most aggressively to the parasite,followed by predator,and finally the control;the results were consistent between the reaction to taxidermy specimens and 3D-printed animal models,indicating that 3D-printed models could serve as a substitute for taxidermy specimens.We propose a series of advantages of using 3D-printed models and suggest them to be a standard method for widespread use in future studies of avian brood parasitism.
文摘Introduction: Intestinal parasitism has been a challenge to overcome for the Mexican deworming campaign and this study determined the prevalence of these infections in schoolchildren treated with albendazole in Northwestern Mexico. Methods: Study sites in marginal conditions, with gastrointestinal infections and albendazole intervention were selected. The Faust and Kato Katz techniques were used to identify the parasites spp. and the NCSS software was used for statistical analysis. Results: A total of 450, 389 and 364 schoolchildren participated in 2005, 2006, and 2007 respectively during this study. The mean age was 7.9 (±1.3). The estimated prevalences were of 42%, 30% and 37% for protozoa infections, and 11%, 12% and 11% for helminth infections in 2005, 2006 and 2007 respectively. Conclusion: The education strategies should be integrated into the Mexican deworming campaign.
基金supported by a grant through‘Quota Scheme’at Norwegian University of Science and Technology(NTNU)
文摘The Plaintive Cuckoo(Cacomantis merulinus) is a widespread brood parasite in Asia, but no data on host species utilization in Bangladesh exist. By searching for nests of all possible host species of the Plaintive Cuckoo at Jahangirnagar university campus, north of Dhaka, we were able to determine which hosts were used in this area. We found that the Common Tailorbird(Orthotomus sutorius) was the only potential host used by Plaintive Cuckoos, and parasitism rate was rather high(31.3 %, n = 16). However, both host and cuckoo breeding success was poor(0 %, n = 16) due to frequent nest predation. Details on host and cuckoo egg appearance are provided. Our findings indicate that Common Tailorbirds are common hosts of the Plaintive Cuckoo in Central Bangladesh.
文摘The reniform nematode (RN), Rotylenchulus reniformis, is an agriculturally important pest with a broad host range that results in a large economic impact in tropical, subtropical and in warm temperate zones. In an initial effort to understand the transcriptome and gene expression in RN, we present EST results that reveal numerous putative parasitism-related genes some of which play roles in plant cell wall modification. The characterized contigs included 8362 (40.6%) matches to unique proteins. Coding contigs predicted were 10,656 (51.7%) or 3079 (14.9%), that was similar to those identified in Brugia malayi and Caenorhabditis elegans as reference organisms respectively. Specific transcripts studied in more detail include putative plant parasitism genes, prominent among them were several plant cell wall modification genes. Contigs matching 14 parasitism genes found in sedentary endoparasitic nematodes included expansins, hexosaminidase, glycosyl hydrolases family, 14-3-3 protein, xylanases, glutathione peroxidase, pectate lyase, β-1,4-endoglucanase, major sperm protein, aminopeptidase, c-type lectin, chitin synthase, FMR famide-like peptide, and calreticulin. These genes function in suppression of host defenses and development of feeding sites.
文摘正We are pleased to publish the second special issue on avian brood parasitism and to be responsible guest editors for the two special issues of Chinese Birds (Vol. 3, No. 4, 2012 and Vol. 4, No. 1, 2013), entitled "Avian Brood Parasitism - A Growing Research Area in Behavioral Ecology". The first issue was published in December 2012. The goal of the two special issues is to publish accumulated knowledge and some of the recent developments
文摘Tea tortrix, Homona coffearia Nietner (Lepidoptera: Tortricidae), is a seasonal pest of tea in Sri Lanka. Though it is active in dry weather, it is observed that populations do occur in wet weather causing serious damage to tea. The parasite, Macrocentrus homonae Nixon (Hymenoptera: Braconidae), controls the tortrix populations, but the efficiency of Macrocentrus has been reduced on account of hyperparasites in recent times. Level of hyperparasitism was studied in some tea tortrix prone areas in the up country region to study how this affected the tortrix populations during wet weather. The hyperparasitism varied during the study period of which average values observed ranged from 35% to 52% in the plantations studied. A negative linear relationship was observed between the average number of parasite cocoons in a cocoon mass and the percentage hyperparasitism. Three generations of tortrix were evident during the study period of May to November 2005. It is observed that tortrix populations do occur in dry and wet weather, and that hyperparasitism has been identified as the major cause affecting the efficient control of tortrix by the parasite. Possibilities of tea tortrix control in wet weather are discussed.
文摘正Invited participants on the 3rd International Symposium on Avian Brood Parasitism, sponsored by Hainan Normal University (HNU), China, Norwegian University of Science and Technology (NTNU), Norway, the Research Council of Norway, and China Ornithological Society (COS).
文摘Objective:To ascertain the level of intestinal parasites vis-a-vis the quality of housing and water supply,and sanitary conditions among the people of Kuraje village in Zamfara state. Methods:The study was cross sectional in nature.Individual households were selected using systematic random sampling methods and pre-tested questionnaires were administered to all the members of each household.Stool samples were collected and processed using standard laboratory procedures.Housing conditions,sources of water and sanitary conditions of the households were also inspected.Results were analysed using Epi Info 2006 model.Results: The prevalence of intestinal parasites was 67.0%(347/519).72.3%(251/347),17.0%(59/347),and 10.7%(37/347) had one,two and three or more parasites,respectively.The associated factors with intestinal parasites were poor housing and sanitary conditions,lack of potable water and illiteracy.The commonest parasites encountered were hookworm(22.0%),Ascaris lumbricoides (18.5%),and Strongyloides stercoralis(15.6%) while the least common was Enterobius vermicularis (1.6%).Others were Giardia lamblia(5.7%),Hymenolepsis nana(5.0%),Trichuris trichiura(8.8%), Entamoeba histolytica(14.4%) and Schistosoma mansoni(8.4%).Conclusions:The infection rate of intestinal parasites in Kuraje village is high.More efforts should be intensified towards improvement in sanitary and housing standards,supply of potable water and institution of a more comprehensive literacy programme for the people of the community.
文摘Captivity of wild animals and restriction of their movement can lead to stress, resulting in suppressed immune response and reduced disease resistance ability. Wild animals in zoological gardens can predominately affected by various gastro-intestinal parasites. This study was therefore, conducted to determine occurrence, identify types and assess seasonal variation of gastrointestinal parasites in captive animals at the Zoological garden of Haramaya University. The study involved a retrospective investigation of zoo records and fecal examinations. Twenty two fecal samples were collected in December, 2013 from all the animals in the garden and examined using concentration and fecal culture techniques. Sampling was repeated after four months in April, 2014 to assess seasonal variations of the parasites. The result from the retrospective study showed death of 21 animals in the last five years. Fecal examination confirmed presence of gastrointestinal parasites with an overall mean prevalence rate of 73.8%. A total of 9 parasite taxa were identified of which 6 (66.67%) and 4 (33.33%) were helminths and protozoa respectively. No Cestode and Trematode species were recovered. <i>Trichuris spp.</i>, <i>Toxocara spp.</i>, <i>Strongyloides spp.</i>, <i>Toxascaris leonine</i>, <i>Passalurus ambiguous</i> and <i>Ascaridia spp.</i> were the helminth parasites observed in the garden. <i>Entamoeba spp.</i>, <i>Isospora spp.</i> and <i>Eimeria spp.</i> were the protozoan parasites encountered. No remarkable seasonal variation in parasitic infection was noticed in the garden. The study revealed occurrence of gastrointestinal parasites in the zoological garden, most of which are zoonotic and hence future studies are needed to determine risks of cross-transmission.
基金funded by the National Natural Science Foundation of China (Nos. 31970427 and 32270526 to WL)。
文摘The interactions between avian brood parasites and their hosts provide an informative and easy-to-handle system for studying coevolution.Avian brood parasitism reduces the reproductive success of hosts,and thus,hosts have evolved anti-parasitic strategies,such as rejecting parasitic eggs and adopting aggressive nest defense strategies,to avoid the cost brought on by brood parasitism.To test whether host anti-parasitic strategies are adjusted with the risk of being parasitized when the breeding seasons of brood parasites and hosts are not synchronous,we conducted a field experiment assessing nest defense and egg recognition behaviors of the Isabelline Shrike(Lanius isabellinus),a host of the Common Cuckoo(Cuculus canorus).In the local area,the host Isabelline Shrike begins to breed in April,whereas the summer migratory Common Cuckoo migrates to the local area in May and begins to lay parasitic eggs.Results showed that nest defense behaviors of the Isabelline Shrike increases significantly after cuckoo arrival,showing higher aggressiveness to cuckoo dummies,with no significant difference in attack rates among cuckoo,sparrowhawk and dove dummies,but their egg rejection did not change significantly.These results imply that Isabelline Shrikes may adjust their nest defense behavior,but not egg rejection behavior,with seasonality.
文摘Coevolutionary arms races between brood parasites and hosts provide tractable systems for understanding antagonistic coevolution in nature;however,little is known about the fate of frontline antiparasite defenses when the host“wins”the coevolutionary arms race.By recreating bygone species interactions,using artificial parasitism experiments,lingering defensive behaviors that evolved in the context of parasitism can be understood and may even be used to identify the unknown agent of parasitism past.Here we present the first study of this type by evaluating lingering“frontline”nest defenses that have evolved to prevent egg laying in a former brood parasite host.The Australian reed warbler Acrocephalus australis is currently not parasitized but is known to exhibit fine-tuned egg discrimination—a defensive behavior indicative of a past brood parasite–host arms race and common in closely related parasitized species.Here,using 3D-printed models of adult brood parasites,we examined whether the Australian reed warbler also exhibits frontline defenses to adult brood parasites,and whether we could use these defenses to identify the warbler’s“ghost of parasitism past.”Our findings provide evidence that the Australian reed warbler readily engages in frontline defenses that are considered adaptive specifically in the context of brood parasitism.However,individuals were unable to discriminate between adults of different brood parasite species at their nest.Overall,our results demonstrate that despite a relaxation in selection,defenses against brood parasitism can be maintained across multiple stages of the host’s nesting cycle,and further suggest that,in accordance with previous findings,that learning may be important for fine-tuning frontline defense.
基金McKenzie Fellowship from University of Melbourne.N.E.L.the Australian Research Council grant DPI80100021a Wolfson Merit Award from the Royal Society.
文摘A fun dame ntal question in biology is how diversity evolves and why some clades are more diverse than others.Phenotypic diversity has often been shown to result from morphological adaptation to different habitats.The role of behavioral interactions as a driver of broadscale phenotypic diversity has received comparatively less attention.Behavioral interactions,however,are a key agent of natural selection.Antagonistic behavioral interactions with predators or with parasites can have significant fitness consequences,and hence act as strong evolutionary forces on the phe no type of species,ultimately gen erating diversity betwee n species of both victims and exploiters.Avian obligate brood parasites lay their eggs in the nests of other species,their hosts,and this behavioral interaction between hosts and parasites is often considered one of the best examples of coevolution in the natural world.In this review,we use the coevolution between brood parasites and their hosts to illustrate the potential of behavioral interactions to drive evolution of phenotypic diversity at different taxonomic scales.We provide a bridge between behavioral ecology and macroevolution by describing how this interaction has increased avian phenotypic diversity not only in the brood parasitic clades but also in their hosts.
基金This research was funded by the Ningxia Agriculture Integrated Development and Sci-tech Extension Program(Grant no.znnfkj2015).
文摘As solitary nymphal parasitoids of Pamtrioza sinica,the ectoparasitoid Tamarixia lyciumi and the endoparasitoid Psyllaephagus arenarius act as effective biocontrol agents.Thus,it is necessary to facilitate mass productions of both species.Despite showing an excellent parasitic ability,Ps.arenarius is often trapped fatally inside 5th-instar nymphs of Pa.sinica due to strong host immunity.To improve the emergence rate of Ps.arenarius,we evaluated whether Ps.arenarius could utilize T.lyciumi venom via multiparasitism,so the parasitism characteristics of both species were examined between separate-existence(monoparasitism only)and co-existence(mono-and multiparasitism)systems.Further,the parasitism characteristics of Ps.arenarius on venom-injected hosts with/without T.lyciumi eggs were tested to further identify the facilitator.The results showed the parasitism rate of T.lyciumi was increased while that of Ps.arenarius did not change from separate-existence to co-existence systems.The intrinsic performances of two species in monoparasitism did not differ between separate-and co-existence systems.From monoparasitism(separate-existence)to multiparasitism(co-existence),no differences were detected in the intrinsic performances of T.lyciumi,but those of Ps.arenarius were greatly improved.After T.lyciumi venom injection,the parasitism characteristics of Ps.arenarius did not differ between venom-injected hosts with T.lyciumi eggs and those without,further indicating Ps.arenarius benefited from the venom of T.lyciumi females rather than T.lyciumi egg/larval secretions.Instead of negative effects,multiparasitism with ectoparasitoids improves endoparasitoids due to ectoparasitic venom.The study increases host resource utilization and provides creative ways for mass production of endoparasitoids.
文摘The harmonics that appear in the squirrel cage asynchronous machine have been discussed in great detail in the literature for a long time. However, the systematization of the phenomenon is still pending, so we made an attempt to fill this gap in the previous parts of our study by elaborating formulas for calculation of parasitic torques. It was a general demand among those who work in this field towards the author to verify his formulas with measurements. In the literature, it seems,only one detailed, purposeful series of measurements has been published so far, the purpose of which was to investigate the effect of the number of rotor slots on the torque-speed characteristic curve of the machine. The main goal of this study is to verify the correctness of the formulas by comparing them with the referred series of measurements. Relying on this, the expected synchronous parasitic torques were developed for the frequently used rotor slot numbers-as a design guide for the engineer.Thus, together with our complete table for radial magnetic pull published in our previous work, the designer has all the principles, data and formulas available for the right number of rotor slots for his given machine and for the drive system. This brings this series of papers to an end.
基金supported by the Academic Excellence Foundation of BUAA for PhD Studentsthe National Natural Science Foundation of China (Grant Number: 52001016)
文摘Based on the attributes of nonflammability,environmental benignity,and cost-effectiveness of aqueous electrolytes,as well as the favorable compatibility of zinc metal with them,aqueous zinc ions batteries(AZIBs)become the leading energy storage candidate to meet the requirements of safety and low cost.Yet,aqueous electrolytes,acting as a double-edged sword,also play a negative role by directly or indirectly causing various parasitic reactions at the zinc anode side.These reactions include hydrogen evolution reaction,passivation,and dendrites,resulting in poor Coulombic efficiency and short lifespan of AZIBs.A comprehensive review of aqueous electrolytes chemistry,zinc chemistry,mechanism and chemistry of parasitic reactions,and their relationship is lacking.Moreover,the understanding of strategies for suppressing parasitic reactions from an electrochemical perspective is not profound enough.In this review,firstly,the chemistry of electrolytes,zinc anodes,and parasitic reactions and their relationship in AZIBs are deeply disclosed.Subsequently,the strategies for suppressing parasitic reactions from the perspective of enhancing the inherent thermodynamic stability of electrolytes and anodes,and lowering the dynamics of parasitic reactions at Zn/electrolyte interfaces are reviewed.Lastly,the perspectives on the future development direction of aqueous electrolytes,zinc anodes,and Zn/electrolyte interfaces are presented.
基金Supported by Chongqing Municipal Health Commission's Key Discipline Construction Project of Traditional Chinese Medicine Bi Disease,Yu Traditional Chinese Medicine(2021),No.16.
文摘BACKGROUND Ankylosing spondylitis(AS)is a chronic immune-mediated inflammatory disease.The prevailing theory links AS onset to infections in susceptible individuals.Furthermore,infections may impair the immune responses.Numerous studies have investigated links between AS and various infections-bacterial,viral,fungal,and other microorganism infections.However,limited attention has been given to the association between AS and Clonorchis sinensis(C.sinensis)infection.CASE SUMMARY A 27-year-old male with a 10-yr history of AS presented to our hospital with inflammatory lower back pain as the primary manifestation.Ten years ago,the patient had achieved a stable condition after treatment with biological agents.However,he experienced a recurrence of lumbosacral pain with an unexplained cause 10 d before hospital admission.A lumbosacral magnetic resonance imaging(MRI)scan revealed bone marrow edema in the left sacroiliac joint,and laboratory indicators were elevated.Moreover,the presence of C.sinensis eggs was detected in the stool.The patient was prescribed praziquantel,resulting in the disap-pearance of C.sinensis eggs in subsequent routine stool tests and relief from lumbosacral pain.A follow-up MRI scan performed after 4 months revealed a reduction in bone marrow edema around the left sacroiliac joint.CONCLUSION C.sinensis infections could potentially trigger the exacerbation of AS.Clinicians should pay attention to investigating the presence of infections.INTRODUCTION Ankylosing spondylitis(AS)is a chronic inflammatory and rheumatic disease resulting from an imbalance between innate and acquired immune responses[1].While it can affect any part of the spine,its primary symptoms are persistent back pain and stiffness in the lower back and pelvis.The prevalence of AS per 10000 individuals is 23.8 in Europe,31.9 in North America,16.7 in Asia,10.2 in Latin America,and 7.4 in Africa[2].Infections commonly occur in the first 3 months and may act as potential triggers for the first symptoms of AS,often manifesting as gastrointestinal,urinary tract,and respiratory infections of microbiological origin[3,4].Clonorchis sinensis(C.sinensis)infection is a severe parasitic disease affecting millions globally,especially prevalent in China,South Korea,the Far East of Russia,and Vietnam,with an estimated 15 million cases[5].Transmission occurs through the consumption of undercooked freshwater fish containing metacercariae.Adult C.sinensis parasites then establish themselves within the human hepatobiliary system[6].C.sinensis infection triggers the activation of sphingosine 1-phosphate receptor 2,leading to the injury and fibrosis of the hepatobiliary[7].Recent research in a rat model found that C.sinensis infection increases the risk of hepatocellular carcinoma by stimulating hepatic progenitor cell proliferation[8].Complications of C.sinensis infection include cholestasis,cholangitis,biliary system fibrosis,and in severe cases,the development of cholangiocarcinoma[9].Consequently,the primary preventive measure is to abstain from consuming raw or undercooked freshwater fish.Praziquantel is the recommended and effective treatment for this infection[10].While there is existing literature on the coexistence of AS and parasitic infections,there is limited research specifically addressing the simultaneous presence of AS and C.sinensis infection.This case report details a rare scenario of AS coexisting with C.sinensis infection,underscoring the potential impact of C.sinensis infection on AS disease activity.
基金This work was supported by the National Natural Science Foundation of China(32000179 Y.X.)the Strategic Priority Research Program of Chinese Academy of Sciences(XDPB16 J.W.)+2 种基金the CAS"Light of West China"Program(G.S.)the Special Research Assistant of Chinese Academy of Sciences(Y.X.and J.Z.)the Postdoctoral Directional Training Foundation of Yunnan Province(Y.X.).
文摘Orobanchaceae is the largest family of parasiticplants,containing autotrophic and parasiticplants with all degrees of parasitism.This makes it byfar the best family for studying the origin and evolution of plant parasitism.Here we provide three high-quality genomes of orobanchaceous plants,the autotrophic Lindenbergia luchunensis and the holoparasitic plants Phelipanche aegyptiaca and Orobanche cumana.Phylogenomic analysis of these three genomes together with those previously published and the transcriptomes of other orobanchaceous species createda robust phylogeneticframework forOrobanchaceae.We found that an ancient whole-genome duplication(WGD;about 73.48million years ago),which occurred earlierthan theoriginof Orobanchaceae,mighthave contributed totheemergence of parasitism.However,no WGD events occurred in any lineage of orobanchaceous parasites except for Striga after divergence from their autotrophic common ancestor,suggesting that,in contrast with previous speculations,WGD is not associated with the emergence of holoparasitism.We detected evident convergent gene loss in all parasites within Orobanchaceae and between Orobanchaceae and dodder Cuscuta australis.The gene families in the orobanchaceous parasites showed a clear pattern of recent gains and expansions.The expanded gene families are enriched in functions related to the development of the haustorium,suggesting that recent gene family expansions may have facilitated the adaptation of orobanchaceous parasites to different hosts.This study illustrates a stepwise pattern in the evolution of parasitism in the orobanchaceous parasites and will facilitate future studieson parasitism and the control of parasitic plants in agriculture.
基金supported by the University of Malaya Research Grant(RG494-13HTM)the University of Malaya Postgraduate Research Grant(PG032-2014B).
文摘Background:Intestinal parasitic infections(IPIs)among indigenous people have been widely documented in Malaysia,however,the prevalence of these infections remains high.In the past,most studies have focused on specific species of parasites but polyparasitism has received limited attention.In addition,epidemiology studies on indigenous people tend to consider them as a homogenous group,whereas in reality different sub-ethnic groups have different cultural and living practices.Variations in living habits such as personal hygiene practices may predispose different groups to different parasitic infections.To better understand prevalence and risk factors of intestinal parasitism among different sub-ethnic groups,the present study was conducted among two sub-ethnic groups of indigenous people(Temuan and Mah Meri)residing in Selangor state,Malaysia.Methods:A cross-sectional study that focused on two distinct sub-ethnic groups was carried out from February to September 2014.Faecal samples were collected from 186 participants and examined using the formalin-ether sedimentation technique.A molecular approach was adopted to conduct a genetic characterisation of the parasites.Additionally,questionnaires were administered to obtain information on the demographics,socioeconomic backgrounds and behavioural risks relating to the participants,as well as information about their environments.Statistical analyses(i.e.binary and multivariate logistic regression analyses)were performed to measure risk factors.Results:For Temuan communities,trichuriasis(64.2%)was the most common infection found,preceding hookworm infection(34%),ascariasis(7.5%),giardiasis(14.2%)and amoebiasis(7.5%).As for the Mah Meri communities,trichuriasis(77.5%)prevailed over ascariasis(21.3%),hookworm(15%),giardiasis(7.5%)and amoebiasis(3.8%).Significant differences in proportions of trichuriasis,ascariasis and hookworm infections were observed between the Temuan and Mah Meri sub-ethnic groups.Polyparasitism was more common among the Temuan sub-ethnic group(41.5%)compared to the Mah Meri sub-ethnic group(32.5%),with the majority of participants harbouring two parasites concurrently(Temuan:33%,Mah Meri:20%).Trichuris trichiura and Ascaris lumbricoides co-infections were most prevalent(10%)among the Mah Meri communities,while a co-infection of T.trichiura with hookworm(19.8%)was most common among the Temuan communities.Multivariate analyses showed that being unemployed,having a large family and drinking unboiled water were found to be significantly associated with intestinal parasitism.Conclusion:The present study highlights substantial polyparasitism and risk factors for infections in the Temuan and Mah Meri sub-ethnic groups.The high prevalence of IPIs among these two sub-ethnic groups indicates that parasitic infections are important health issues in these communities.Hence,it is imperative to implement sound intervention strategies such as periodic preventive chemotherapy coupled with health education in order to reduce and eradicate these infections.
