Protozoan infections(e.g.,malaria,trypanosomiasis,and toxoplasmosis)pose a considerable global burden on public health and socioeconomic problems,leading to high rates of morbidity and mortality.Due to the limited ars...Protozoan infections(e.g.,malaria,trypanosomiasis,and toxoplasmosis)pose a considerable global burden on public health and socioeconomic problems,leading to high rates of morbidity and mortality.Due to the limited arsenal of effective drugs for these diseases,which are associated with devastating side effects and escalating drug resistance,there is an urgent need for innovative antiprotozoal drugs.The emergence of drug repurposing offers a low-cost approach to discovering new therapies for protozoan diseases.In this review,we summarize recent advances in drug repurposing for various human protozoan diseases and explore cost-effective strategies to identify viable new treatments.We highlight the cross-applicability of repurposed drugs across diverse diseases and harness common chemical motifs to provide new insights into drug design,facilitating the discovery of new antiprotozoal drugs.Challenges and opportunities in the field are discussed,delineating novel directions for ongoing and future research.展开更多
In the present review article human diseases caused by various groups of pathogens have been explained with its etiology,epidemiology and treatment.In addition,effect of climatic changes on parasites and pathogens has...In the present review article human diseases caused by various groups of pathogens have been explained with its etiology,epidemiology and treatment.In addition,effect of climatic changes on parasites and pathogens has been demarcated with rising incidences of diseases.In response to environmental changes,mainly external and internal microenvironment of body and drug regimens taken by patients;virus is regularly changing its form and new mutant variants are coming out.These are circulating in many Indian states and cross border countries and causing high infectivity and mortality in human patients.These variants with new mutations are challenging existing drugs and other prophylactic measures and massively disrupting functions of a tissue,organ,or entire organism.Diseases caused by viruses are showing new trends in virulence,with high infectivity,morbidity and mortality.Due to climatic effect and drug resistance and new mutations in pathogens disease burden has been exacerbated enormously at global level.In all cases of helminthes,protozoan’s,fungi,bacteria,virus pathogens and parasites available drug structure seem to be failed or their usefulness has been much reduced due to evolution of new mutant variants with multiple drug resistance.There are serious failures at the level of operation,management and control of disease.The utmost failure is due to lack of appropriate vaccine,drug regimens,clinical care and awareness among people.These are major reasons that is why diseases become uncontrolled and unmanageable.展开更多
The indicator values of microfauna functional groups and species for treatment performancewere systematically evaluated based on the continuous monitoring of the entire microfauna communities including both protozoa a...The indicator values of microfauna functional groups and species for treatment performancewere systematically evaluated based on the continuous monitoring of the entire microfauna communities including both protozoa and metazoa over a period of 14 months, in two parallel full-scale municipalwastewater treatment systems in a plant in Beijing, China. A total of 57 species of ciliates, 14 species （units） of amoebae, 14 species （units） of flagellates and4 classes of small metazoawere identified,with Arcella hemisphaerica, Vorticella striata, Vorticella convallaria, Epistylis plicatilis and small flagellates （e.g. Bodo spp.） as thedominant protozoa, and rotifers as thedominant metazoa. The abundance of the sessile ciliateswas correlatedwith the removals of BOD 5 （Pearson＇s r = 0.410, p 〈 0.05） and COD Cr （r = 0.397, p 〈 0.05）while the testate amoebaewas significantly positively related to nitrification （r = 0.523, p 〈 0.01）. At the same time, some other associationswere also identified： the abundances of the large flagellates （r = 0.447, p 〈 0.01）, the metazoa （r = 0.718, p 〈 0.01） and species Aspidisca sulcata （r = 0.337, p 〈 0.05）were positively related to nitrification; the abundance of Aspidisca costatawas correlated to the TN （total nitrogen） removal （r = -0.374, p 〈 0.05 ）; the abundances of the sessile species Carchesium polypinum （r = 0.458, p 〈 0.01） and E. plicatilis （r = 0.377, p 〈 0.05）were correlatedwith the removal of suspended solids.展开更多
AIM:It is known that toxoplasmosis rarely leads to various liver pathologies,most common of which is granulomatose hepatitis in patients having normal immune systems.Patients who have cirrhosis of the liver are subjec...AIM:It is known that toxoplasmosis rarely leads to various liver pathologies,most common of which is granulomatose hepatitis in patients having normal immune systems.Patients who have cirrhosis of the liver are subject to a variety of cellular as well as humoral immunity disorders.Therefore,it may be considered that toxoplasmosis can cause more frequent and more severe diseases in patients with cirrhosis and is capable of changing the course of the disease.The aim of this study was to investigate the frequency of toxoplasmosis in patients with cirrhosis. METHODS:Serum samples were taken from 108 patients with cirrhosis under observation in the Hepatology Polyclinic of the Gastroenterology Clinic,and a control group made up of 50 healthy blood donors.IFAT and ELISA methods were used to investigate the IgG and IgM antibodies,which had developed from these sera. RESULTS:Toxoplasma IgG and IgN antibody positivity was found in 74 (68.5%) of the 108 cirrhotic patients and 24 (48%) of the 50 people in the control group.The difference between them was significant (P<0.05). CONCLUSION:In conclusion,it was found that the toxopiasma sero-prevalence in the cirrhotic patients in this study was higher.Cirrhotic patients are likely to form a toxoplasma risk group.More detailed studies are needed on this subject.展开更多
In a completely randomized block design experiment, 16 ruminally cannulated sheep （40 ±2.1 kg）fed a 50% concentrate： 50% forage diet （DM basis） were given intraruminal doses of powdered Yucca schidigera extr...In a completely randomized block design experiment, 16 ruminally cannulated sheep （40 ±2.1 kg）fed a 50% concentrate： 50% forage diet （DM basis） were given intraruminal doses of powdered Yucca schidigera extract （YSE）. Doses of 0 （control）, 100, 200, or 300 mg kg^-1 diet were given at 8 p.m. and 4 a.m. On 15, 16, and 17 d of the experimental period, ruminal contents were sampled 0, 2, 4, 6, and 8 h after dosing, and blood samples were collected at the end of the experiment （18th and 19th d）. Acidity was not affected （P〉0.05） by the addition of YSE. Compared with the control, ruminal propionate concentration was increased by 29.4 and 29.8% （P〉 0.05） and the acetic acid concentration was decreased by 15.1 and 19.8% （P〉0.05） at 4 and 6 h after YSE （300 mg kg^-1） dosing, respectively. Ruminal ammonia concentration in the first 2 h after feeding was higher （P〈0.05） in the sheep that did not receive YSE （increased by 17.57 mg 100 mL^-1） than in those that received 200 mg kg^-1（increased by 6.77 mg 100 mL^-1） or 300 mg kg^-1 （increased by 6.50 mg 100 mL^-1） YSE. Protozoan populations in the rumen were lower （P〈0.05） in the animals that received 300 mg kg^-1 of YSE compared with the control. All serum parameters of the four groups were in the normal range and were similar among the treatment groups （P 〉 0.05）, after being fed for 19 d with different doses of YSE. The effect of YSE on ruminal ammonia concentration likely resulted from a decreased concentration of protozoan populations and, presumably, from ammonia binding by YSE.展开更多
Hexachlorobenzene （HCB） is a chlorinated aromatic hydrocarbon that was widely used for seed dressing in prevention of fungal growth on crops, and also as a component of fireworks, ammunition, and synthetic rubbers. ...Hexachlorobenzene （HCB） is a chlorinated aromatic hydrocarbon that was widely used for seed dressing in prevention of fungal growth on crops, and also as a component of fireworks, ammunition, and synthetic rubbers. Because of its resistance to degradation and mobility, HCB is widely distributed throughout the environment and is accumulated through food chains in different ecosystems. In this study, a preliminary investigation was carried out on the bioaccumulation and the toxic effects of HCB in the microbial （protozoan in particular） communities in the Fuhe River, Wuhan, a water body receiving industrial wastewaters containing HCB and other pollutants, using the standardized polyurethane foam units （PFU） method. Field samples were taken from eight stations established along the Fuhe River in January and August 2006. The concentration ratios of HCB in microbial communities and in water were 9.66-18.64, and the microbial communities accumulated 13.29-56.88 μg/L of HCB in January and 0.82-10.25 μg/L HCB in August. Correlation analysis showed a negative correlation between the HCB contents in the microbial assemblage, and the number of species and the diversity index of the protozoan communities. This study demonstrated the applicability of the PFU method in monitoring the effects of HCB on the level of microbial communities.展开更多
Although microbes have traditionally been used as models for testing ecological theory, research on the organization of these communities has largely been isolated from other areas of community ecology. Early studies ...Although microbes have traditionally been used as models for testing ecological theory, research on the organization of these communities has largely been isolated from other areas of community ecology. Early studies indicated that microbial populations can form dynamic, interacting assemblages. Observations of distributional patterns suggest that certain deterministic forces regulate community structure. It appears that protozoans are tolerant of a wide range of environmental conditions although evidence for this is largely based on gross environmental analyses. Laboratory studies have suggested the importance of negative and positive biotic interactions in determining community membership, but little field evidence for this exists. The importance of transport processes in controlling community composition is being increasingly recognized. All three types of processes likely act to regulate the colonization and successional dynamics of these communities. A simple model is presented to promote the展开更多
Pulmonary protozoal infections are rare. A 28-year-old woman was admitted to hospital with chief complains of cough, sputum, and dyspnea. The clinical laboratory tests for blood revealed an increased eosinophil percen...Pulmonary protozoal infections are rare. A 28-year-old woman was admitted to hospital with chief complains of cough, sputum, and dyspnea. The clinical laboratory tests for blood revealed an increased eosinophil percentage of 31.3%and significantly elevated total IgE. The chest computed tomography scan revealed that bilateral bronchial walls were thickening, accompanied with patchy spots scattered throughout bilateral lungs. A suspected multiflagellated protozoan was observed under a light microscope. But some different features were observed by electron microscopy, such as the orientation of flagella and nucleus. Besides, both bronchoalveolar lavage fluid and bronchoscopic brush smears underwent Gram staining and Pap staining, which revealed that numerous respiratory ciliated cells were scattered or accumulated in the sample.Finally, she was diagnosed with eosinophil pneumonia. Metronidazole,bronchodilators, and mucolytics were taken for 5 d and symptoms and pulmonary ventilation function improved. We herein report a case of chronic eosinophilic pneumonia, which was misdiagnosed as multiflagellated protozoan infection, and it is suggested that reliable diagnosis approaches are necessary,rather than clinical symptoms and morphological features.展开更多
AIM:Intestinal parasitic diseases are commonly accompanied with diarrhoeal symptoms and allergic reactions.Eosinophilia occurs as a result of IL-5 synthesized from Th2 cells during allergic reactions.IL-5 acts as a fa...AIM:Intestinal parasitic diseases are commonly accompanied with diarrhoeal symptoms and allergic reactions.Eosinophilia occurs as a result of IL-5 synthesized from Th2 cells during allergic reactions.IL-5 acts as a factor activating eosinophils. The aim of this study was to compare the IL-5 cytokine measurements in serum samples and cell cultures.And also to compare eosinophilia observed in helminth infections and protozoon infections accompanied with allergy. METHODS:Twenty-three patients who presented with diarrhoeal symptoms and allergic complaints were tested positive for intestinal parasites,as well as 21 controls with allergic complaints who did not have any intestinal parasites were included in this study.IL-5 production in in vitro cell cultures prepared by using phytohemaglutinin (PHA) to stimulate peripheral blood mononuclear cells (PBMC) obtained from the blood samples taken from these patients were compared with the IL-5 level in serum.Furthermore, the IL-5 production in protozoon and helminth infections was also compared.Absolute eosinophil values in 1 mm^3 of blood were calculated by means of peripheral smear in both groups within the scope of the study. RESULTS:Parasites such as helminth detected in 15 (65.2%) and protozoon in 8 (34.8%) of the patients were included in this study.As regards the values of the sera in both patients with parasite infection and controls,the IL-5 production was found to be higher in the cell culture supernatant (P<0.001 and P<0.05).When the IL-5 level of the patients with helminth parasites was compared with that of those with protozoon,it was determined that the IL-5 level in serum was more significant in the patients with protozoon than in those with helminth (P<0.05).In the study group,the patients were found to have parasites, the percentage of eosinophil was 7.0% compared to 6.5% in the control group.Thus,there was no significant difference between the eosinophil values (P>0.05). CONCLUSION:It was found that IL-5 cytokine levels in serum samples from the patients with helminth and protozoon displayed more measurable values as compared to the IL-5 levels after stimulation with mitogen.It is concluded that IL-5 acts as a triggering factor in the toxiallergic complaints commonly seen in helminth and protozoon infections.展开更多
AIM To investigate the putative role of protozoan parasites in the development of irritable bowel syndrome(IBS).METHODS The study included 109 IBS consecutive adult patients fulfilling the RomeⅢcriteria and 100 healt...AIM To investigate the putative role of protozoan parasites in the development of irritable bowel syndrome(IBS).METHODS The study included 109 IBS consecutive adult patients fulfilling the RomeⅢcriteria and 100 healthy control subjects.All study subjects filled a structured questionnaire,which covered demographic information and clinical data.Fresh stool samples were collected from patients and control subjects and processed within less than 2 h of collection.Iodine wet mounts and Trichrome stained smears prepared from fresh stool and sediment concentrate were microscopically examined for parasites.Blastocystis DNA was detected by polymerase chain reaction,and Cryptosporidium antigens were detected by ELISA.RESULTS A total of 109 IBS patients(31 males,78 females)with a mean age±SD of 27.25±11.58 years(range:16-60 years)were enrolled in the study.The main IBS subtype based on the symptoms of these patients was constipation-predominant(88.7%of patients).A hundred healthy subjects(30 males,70 females)with a mean±SD age of 25.0±9.13 years(range 18-66 years)were recruited as controls.In the IBS patients,Blastocystis DNA was detected in 25.7%,Cryptosporidium oocysts were observed in 9.2%,and Giardia cysts were observed in 11%.In the control subjects,Blastocystis,Cryptosporidium and Giardia were detected in 9%,0%,and 1%,respectively.The difference in the presence of Blastocystis(P=0.0034),Cryptosporidium(P=0.0003),and Giardia(P=0.0029)between IBS patients and controls was statistically significant by all methods used in this study.CONCLUSION Prevalence of Blastocystis,Cryptosporidium and Giardia is higher in IBS patients than in controls.These parasites are likely to have a role in the pathogenesis of IBS.展开更多
Wastewater effluents containing phosphorus and nitrogen are major contributors to a variety of water pollution.The present study is therefore aimed at investigating the phosphate and nitrate removal efficiency of thre...Wastewater effluents containing phosphorus and nitrogen are major contributors to a variety of water pollution.The present study is therefore aimed at investigating the phosphate and nitrate removal efficiency of three wastewater protozoa(Aspidisca, Trachelophyllum and Peranema) in a laboratory-scale water treatment system.The system was made of two separate reactors(aerated and non-aerated) and展开更多
BACKGROUND Leishmaniasis includes a range of chronic infections in humans and animals and can be caused by more than 20 species of Leishmania protozoa.The manifestations of leishmaniasis are diverse and dependent on t...BACKGROUND Leishmaniasis includes a range of chronic infections in humans and animals and can be caused by more than 20 species of Leishmania protozoa.The manifestations of leishmaniasis are diverse and dependent on the immune response capacity of the host and the type of Leishmania.In East Asia,leishmaniasis is relatively rare and prone to misdiagnosis and underdiagnosis.CASE SUMMARY We report a case of a 36-year-old male with cutaneous leishmaniasis.The patient had been misdiagnosed with a bacterial skin infection and was given a dressing change and oral levofloxacin,which proved ineffective.Histopathological examination revealed amastigote(Leishman-Donovan body)in the histocytes,and nucleic acid sequencing proved that the pathogen was Leishmania major.The patient was treated successfully by regional injection of sodium gluconate(600 mg)three times.The ulcer healed and did not recur at 1.5-year follow-up.CONCLUSION Skin ulcers caused by leishmaniasis are easily misdiagnosed in non-epidemic countries,yet it should not be overlooked.展开更多
Tritrichomonas foetus is a flagellate protozoan and the etiological agent of bovine genital tri-chomoniasis [1], which is an infectious vene- real disease. This parasite is usually found as- sociated with the mucosal ...Tritrichomonas foetus is a flagellate protozoan and the etiological agent of bovine genital tri-chomoniasis [1], which is an infectious vene- real disease. This parasite is usually found as- sociated with the mucosal surface of the uro- genital tract in females or the male preputial and penile membranes. In females, the clinical ma-nifestations may include abortion, with repe- tition of estrus at irregular intervals, vaginitis, cervicitis, endometritis, and pyometra. Parasi- tized males may have a discharge with small nodules in the preputial membrane. After that, the bulls have no clinical symptoms, and are thus an asymptomatic carrier that may spread the infection. Considering that a bull could cover up to twenty females [2], bovine genital trichomoniasis is a serious medical and veteri- nary problem, with economical repercussion for beef and milk production. As T. foetus is an amitochondrial and aerotolerant organism, en- ergy production under low O2 tension in the protozoan is done via hydrogenosome, which, as the name suggests, is the organelle where H2 is generated [3,4,5]. The molecular machinery of mitochondrial cell death is, therefore, absent in this parasite and the mechanism that activates of cell death program is not clear. This review seeks to understand the characteristics of the protozoan parasite T. foetus in order to propose new therapies for animals suffering from this infectious and contagious agent.展开更多
The histological basis for acute osteocyte mechanosensitivity remains uncertain. A novel bone cell model of mechanotransduction and inorganic trafficking may be the powerful, silt-burrowing protozoan Spirostomum ambig...The histological basis for acute osteocyte mechanosensitivity remains uncertain. A novel bone cell model of mechanotransduction and inorganic trafficking may be the powerful, silt-burrowing protozoan Spirostomum ambiguum which when being physically challenged fabricates within vesicles populations of bone-like calcium phosphate microspheres, about 1 μm in diameter. These not only attribute considerable compression-resilience but also resemble the Golgi-directed mineral assemblies we recently reported in osteocytes. Advantageously, calcification in the protozoan (confirmed by ultramicroscopy with EDX elemental microanalysis) enabled Golgi comparison under overt, natural phases of both high (i.e. silt-tunnelling) and low (i.e free-swimming) stress. Established hard-tissue microscopy techniques previously positive in bone cells included quantitative fluorescent tetracycline labelling for bone salt together with the same metazoan Golgi body marker (Green Fluorescent Protein-tagged mannosidase II construct). Organellar modulation was monitored by transfection of live organisms in situ (some post-stained with red nuclear fluorochrome TOPRO-3). Results showed that GFP-tagged Golgi fluorescence increased from swimmers (mean 74.5 ± SD 6.7 AU) to burrowers (mean 104.6 ± SD 2.7;p < 0.0001) synchronous with juxtanuclear tetracycline-labelled mineral fluorescence (swimmers, mean 89.7 ± SD 3.3 AU;burrowers, mean 138.0 ± SD 4.0;p < 0.0001). Intracellular dense microspheres, single or bridged, were harvested as pellets rich in Ca, P (Ca:P 0.98) and Si, their polarised alignment moving from transaxial in swimmers to axial in burrowers. It was concluded that Golgi-directed mineral fabrication in the large, accessible, silt-enclosed ciliate resembles that in the smaller, less-accessible bone cell and may be a conserved early mechanobiological intracellular development predicating force translation into compression-resistant mineral fabrication in loaded segments of the osteocyte syncitium.展开更多
Vibrio harveyi, known as a pathogenic bacterium caused severe secondary bacterial infections of the large yellow croaker Larimichthys crocea, was identified as an endosymbiont in the marine parasitic ciliate protozoan...Vibrio harveyi, known as a pathogenic bacterium caused severe secondary bacterial infections of the large yellow croaker Larimichthys crocea, was identified as an endosymbiont in the marine parasitic ciliate protozoan Cryptocaryon irritans. Meta 16 S sequencing method was used to identify the bacterial flora in C. irritans, and V.harveyi was isolated via culture-dependent method. Vibrio harveyi was observed in cytoplasm of C. irritans at the stage of tomont both by transmission electron microscopy and by Fluorescence in situ hybridization; no signal,however, was detected in nucleus area. The relationship between V. harveyi and C. irritans and the role of endosymbiotic V. harveyi in C. irritans merit further investigation.展开更多
A field study was conducted to evaluate the protozoan colonization patterns on artificial substrates in relation to organic pollution within a tropical harbour. The composition of protozoans and their succession rate...A field study was conducted to evaluate the protozoan colonization patterns on artificial substrates in relation to organic pollution within a tropical harbour. The composition of protozoans and their succession rates on artificial substrates(polyurethane foam units) were compared between two field stations(A and B), and their presence were considered with regards to the prevailing water quality conditions at the study sites. Altogether 44 genera of flagellates and ciliates were documented. The common genera of flagellates encountered included Monas, Polytoma, and Chromalina. Among the ciliates, the predominant genera were Tetrahymena, Vorticella, Lagynophyra, and Heloiphyra. These groups exhibited characteristic successional patterns in relation to ambient water quality. At Station A, located close to the sewage outfall, the water quality parameters included poor Secchi disc transparency(0.48m), dissolved oxygen of 1.93 mg/ml, salinity of 18 psu, and temperature 31.3 ℃. Here, the nanoflagellates( spumella ) colonized first, followed by microcilliate( Tetrahymena ) and sessile form( Vorticella ). Station B, located on the seaward side, was characterized by relatively less stressed environmental conditions with transparency 1.85m and dissolved oxygen value of 6 04 mg/ml. Salinity of 27.27 psu, and mean temperature of 30 ℃ were recorded at “B'. At this station, the nanoflagellate Polytoma was first documented to colonize on the substrates, followed by microcilliate( Lagynophrya ) and suctorid( Heliophyra ). These findings support the use of protozoans as indicator species for evaluating the hazards posed by organic pollution to natural estuarine communities.展开更多
A correct antibody response requires the participation of both B and T lymphocytes and antigen presenting cells. In this review we address the role of follicular helper T lymphocytes(T FH) in this reaction. We shall f...A correct antibody response requires the participation of both B and T lymphocytes and antigen presenting cells. In this review we address the role of follicular helper T lymphocytes(T FH) in this reaction. We shall focus on the regulation of their development and function in health and disease. T FH can be characterized on the basis of their phenotype and the pattern of secretion of cytokines. This fact is useful to study their participation in the generation of antibody deficiency in primary immunodeficiency diseases such as common variable immunodeficiency, X-linked hyper Ig M syndrome orX-linked lymphoproliferative disease. Increased numbers of T FH have been demonstrated in several autoimmune diseases and are thought to play a role in the development of autoantibodies. In chronic viral infections caused by the human immunodeficiency virus, hepatitis B or C virus, increased circulating T FH have been observed, but their role in the protective immune response to these agents is under discussion. Likewise, an important role of T FH in the control of some experimental protozoan infections has been proposed, and it will be important to assess their relevance in order to design effective vaccination strategies.展开更多
Intestinal infections affect approximately 450 million people globally,predominantly impacting children and immunocompromised individuals in lowand middle-income countries(LMICs)due to inadequate water,sanitation,and ...Intestinal infections affect approximately 450 million people globally,predominantly impacting children and immunocompromised individuals in lowand middle-income countries(LMICs)due to inadequate water,sanitation,and hygiene(WASH)conditions,poverty,malnutrition,and low literacy.In Kenya,the prevalence of intestinal infections is elevated by warm tropical climates and socioeconomic factors.This scoping review evaluates the national prevalence,risk factors,and contamination sources of intestinal protozoa in Kenya,using a One Health approach to synthesize existing data from various human,animal,and environmental studies.A comprehensive literature search identified 292 studies,of which 67 met the inclusion criteria,covering the period from 1966 to 2024.The review found that most studies utilized stool microscopy,a method with limited sensitivity,and largely focused on vulnerable human populations,with minimal investigation into environmental reservoirs.Key protozoa identified included Entamoeba histolytica,Cryptosporidium,and Giardia,with transmission driven by poor WASH conditions,environmental factors,and close humananimal interactions.The findings highlight significant gaps in environmental surveillance and suggest the need for a robust,integrated One Health approach to better understand and control protozoan infections in Kenya.展开更多
The adaptive strategies of prey against predation risk have been pivotal in non-consumptive effects.However,the adaptive strategies of prey and the response mechanisms to various predation risk cues remain unclear.We ...The adaptive strategies of prey against predation risk have been pivotal in non-consumptive effects.However,the adaptive strategies of prey and the response mechanisms to various predation risk cues remain unclear.We hypothesized that prey adopt a similar adaptive strategy to address different predation risks,but their response mechanisms depend on the attributes of predation risk cues.To test this hypothesis,we used Didinium-Paramecium as a predator-prey model to first evaluate the effects of various predation risk cues,including homogenates of predators(TD)and prey(TP)alone or in combination(TM),and the density of conspecific prey on the specific growth rate(SGR)to determine their adaptive strategies and their underlying response mechanisms based on transcriptomic analysis.Our results show that predation risk cues considerably enhance prey SGR,with effects in descending order of TM,TD,and TP.However,such effects gradually decrease as the density of conspecific prey increases until they disappear.The trend in the levels of differentially expressed genes(DEGs)in prey exposed to different predation risk cues is similar to that of SGRs.In particular,pathways based on DEG enrichment mediated by predation risk cues involve cellular processes,nutrient metabolism,and synthesis of biological macromolecules.However,they differ in type,number,and location within specific biological processes.In conclusion,Paramecium uses early reproduction strategies to address the risk of predation caused by different cues,and differences in its response mechanisms depend on the attributes of the cues of predation risk,resulting in differences in the SGR of the prey.展开更多
Melanization of shrimp gills is a general symptom in shrimp black bill diseases(sBG);therefore,the cause is not immediately apparent.This study aimed to determine the primary and secondary agents associated with a bla...Melanization of shrimp gills is a general symptom in shrimp black bill diseases(sBG);therefore,the cause is not immediately apparent.This study aimed to determine the primary and secondary agents associated with a black gill outbreak in the Delvar complex in the Bushehr Province of Iran.During July and August of 2020,450 healthy and affected shrimps were collected based on brown to black gill color from three farms of the Bushehr Province in Iran.Characterization of pathogens was performed by gross signs,wet mounts,microbiological tests,histopathology methods,and sequencing of molecular markers.The mean weight and length of infected shrimps was significantly(P<0.05)lower than the healthy shrimps.The histological examination of sBG indicated the adhesion of secondary lamellae,accumulation of hemocyte cells at the end of the secondary lamellae,and necrosis of epithelial cells with pyknosis and karyorrhexis.According to our results,Aspergillus sydowii as a primary agent correlates with sBG disease in Litopenaeus vannamei from Iran,and other biotic factors,including bacterial(Vibrio owensii and V.parahaemolyticus)probably are secondary agents associated with sBG disease.展开更多
基金financially supported by the National Natural Science Foundation of China(Grant Nos.:32270690 and 32070671)the Postdoctor Research Fund of West China Hospital,Sichuan University,China(Grant No.:2024HXBH059)。
文摘Protozoan infections(e.g.,malaria,trypanosomiasis,and toxoplasmosis)pose a considerable global burden on public health and socioeconomic problems,leading to high rates of morbidity and mortality.Due to the limited arsenal of effective drugs for these diseases,which are associated with devastating side effects and escalating drug resistance,there is an urgent need for innovative antiprotozoal drugs.The emergence of drug repurposing offers a low-cost approach to discovering new therapies for protozoan diseases.In this review,we summarize recent advances in drug repurposing for various human protozoan diseases and explore cost-effective strategies to identify viable new treatments.We highlight the cross-applicability of repurposed drugs across diverse diseases and harness common chemical motifs to provide new insights into drug design,facilitating the discovery of new antiprotozoal drugs.Challenges and opportunities in the field are discussed,delineating novel directions for ongoing and future research.
文摘In the present review article human diseases caused by various groups of pathogens have been explained with its etiology,epidemiology and treatment.In addition,effect of climatic changes on parasites and pathogens has been demarcated with rising incidences of diseases.In response to environmental changes,mainly external and internal microenvironment of body and drug regimens taken by patients;virus is regularly changing its form and new mutant variants are coming out.These are circulating in many Indian states and cross border countries and causing high infectivity and mortality in human patients.These variants with new mutations are challenging existing drugs and other prophylactic measures and massively disrupting functions of a tissue,organ,or entire organism.Diseases caused by viruses are showing new trends in virulence,with high infectivity,morbidity and mortality.Due to climatic effect and drug resistance and new mutations in pathogens disease burden has been exacerbated enormously at global level.In all cases of helminthes,protozoan’s,fungi,bacteria,virus pathogens and parasites available drug structure seem to be failed or their usefulness has been much reduced due to evolution of new mutant variants with multiple drug resistance.There are serious failures at the level of operation,management and control of disease.The utmost failure is due to lack of appropriate vaccine,drug regimens,clinical care and awareness among people.These are major reasons that is why diseases become uncontrolled and unmanageable.
基金supported by the Chinese Academy of Sciences(No.KZCX2-YW-JC407)the National Natural Science Foundation of China(No.20921140094)
文摘The indicator values of microfauna functional groups and species for treatment performancewere systematically evaluated based on the continuous monitoring of the entire microfauna communities including both protozoa and metazoa over a period of 14 months, in two parallel full-scale municipalwastewater treatment systems in a plant in Beijing, China. A total of 57 species of ciliates, 14 species （units） of amoebae, 14 species （units） of flagellates and4 classes of small metazoawere identified,with Arcella hemisphaerica, Vorticella striata, Vorticella convallaria, Epistylis plicatilis and small flagellates （e.g. Bodo spp.） as thedominant protozoa, and rotifers as thedominant metazoa. The abundance of the sessile ciliateswas correlatedwith the removals of BOD 5 （Pearson＇s r = 0.410, p 〈 0.05） and COD Cr （r = 0.397, p 〈 0.05）while the testate amoebaewas significantly positively related to nitrification （r = 0.523, p 〈 0.01）. At the same time, some other associationswere also identified： the abundances of the large flagellates （r = 0.447, p 〈 0.01）, the metazoa （r = 0.718, p 〈 0.01） and species Aspidisca sulcata （r = 0.337, p 〈 0.05）were positively related to nitrification; the abundance of Aspidisca costatawas correlated to the TN （total nitrogen） removal （r = -0.374, p 〈 0.05 ）; the abundances of the sessile species Carchesium polypinum （r = 0.458, p 〈 0.01） and E. plicatilis （r = 0.377, p 〈 0.05）were correlatedwith the removal of suspended solids.
文摘AIM:It is known that toxoplasmosis rarely leads to various liver pathologies,most common of which is granulomatose hepatitis in patients having normal immune systems.Patients who have cirrhosis of the liver are subject to a variety of cellular as well as humoral immunity disorders.Therefore,it may be considered that toxoplasmosis can cause more frequent and more severe diseases in patients with cirrhosis and is capable of changing the course of the disease.The aim of this study was to investigate the frequency of toxoplasmosis in patients with cirrhosis. METHODS:Serum samples were taken from 108 patients with cirrhosis under observation in the Hepatology Polyclinic of the Gastroenterology Clinic,and a control group made up of 50 healthy blood donors.IFAT and ELISA methods were used to investigate the IgG and IgM antibodies,which had developed from these sera. RESULTS:Toxoplasma IgG and IgN antibody positivity was found in 74 (68.5%) of the 108 cirrhotic patients and 24 (48%) of the 50 people in the control group.The difference between them was significant (P<0.05). CONCLUSION:In conclusion,it was found that the toxopiasma sero-prevalence in the cirrhotic patients in this study was higher.Cirrhotic patients are likely to form a toxoplasma risk group.More detailed studies are needed on this subject.
文摘In a completely randomized block design experiment, 16 ruminally cannulated sheep （40 ±2.1 kg）fed a 50% concentrate： 50% forage diet （DM basis） were given intraruminal doses of powdered Yucca schidigera extract （YSE）. Doses of 0 （control）, 100, 200, or 300 mg kg^-1 diet were given at 8 p.m. and 4 a.m. On 15, 16, and 17 d of the experimental period, ruminal contents were sampled 0, 2, 4, 6, and 8 h after dosing, and blood samples were collected at the end of the experiment （18th and 19th d）. Acidity was not affected （P〉0.05） by the addition of YSE. Compared with the control, ruminal propionate concentration was increased by 29.4 and 29.8% （P〉 0.05） and the acetic acid concentration was decreased by 15.1 and 19.8% （P〉0.05） at 4 and 6 h after YSE （300 mg kg^-1） dosing, respectively. Ruminal ammonia concentration in the first 2 h after feeding was higher （P〈0.05） in the sheep that did not receive YSE （increased by 17.57 mg 100 mL^-1） than in those that received 200 mg kg^-1（increased by 6.77 mg 100 mL^-1） or 300 mg kg^-1 （increased by 6.50 mg 100 mL^-1） YSE. Protozoan populations in the rumen were lower （P〈0.05） in the animals that received 300 mg kg^-1 of YSE compared with the control. All serum parameters of the four groups were in the normal range and were similar among the treatment groups （P 〉 0.05）, after being fed for 19 d with different doses of YSE. The effect of YSE on ruminal ammonia concentration likely resulted from a decreased concentration of protozoan populations and, presumably, from ammonia binding by YSE.
基金Project supported by the Key Project of Chinese Ministry of Education(No.104250).
文摘Hexachlorobenzene （HCB） is a chlorinated aromatic hydrocarbon that was widely used for seed dressing in prevention of fungal growth on crops, and also as a component of fireworks, ammunition, and synthetic rubbers. Because of its resistance to degradation and mobility, HCB is widely distributed throughout the environment and is accumulated through food chains in different ecosystems. In this study, a preliminary investigation was carried out on the bioaccumulation and the toxic effects of HCB in the microbial （protozoan in particular） communities in the Fuhe River, Wuhan, a water body receiving industrial wastewaters containing HCB and other pollutants, using the standardized polyurethane foam units （PFU） method. Field samples were taken from eight stations established along the Fuhe River in January and August 2006. The concentration ratios of HCB in microbial communities and in water were 9.66-18.64, and the microbial communities accumulated 13.29-56.88 μg/L of HCB in January and 0.82-10.25 μg/L HCB in August. Correlation analysis showed a negative correlation between the HCB contents in the microbial assemblage, and the number of species and the diversity index of the protozoan communities. This study demonstrated the applicability of the PFU method in monitoring the effects of HCB on the level of microbial communities.
文摘Although microbes have traditionally been used as models for testing ecological theory, research on the organization of these communities has largely been isolated from other areas of community ecology. Early studies indicated that microbial populations can form dynamic, interacting assemblages. Observations of distributional patterns suggest that certain deterministic forces regulate community structure. It appears that protozoans are tolerant of a wide range of environmental conditions although evidence for this is largely based on gross environmental analyses. Laboratory studies have suggested the importance of negative and positive biotic interactions in determining community membership, but little field evidence for this exists. The importance of transport processes in controlling community composition is being increasingly recognized. All three types of processes likely act to regulate the colonization and successional dynamics of these communities. A simple model is presented to promote the
基金Supported by the National Natural Science Foundation of China,No.81500430 and No.U1304802the Science and Technology Planning Project of Henan Province,No.182102310567,No.182102310544,and No.182102310566+1 种基金the Henan Medical Science and Technology Tackling Project,No.201702136Key Project of Science and Technology Research of Education Department of Henan Province,No.17A320019
文摘Pulmonary protozoal infections are rare. A 28-year-old woman was admitted to hospital with chief complains of cough, sputum, and dyspnea. The clinical laboratory tests for blood revealed an increased eosinophil percentage of 31.3%and significantly elevated total IgE. The chest computed tomography scan revealed that bilateral bronchial walls were thickening, accompanied with patchy spots scattered throughout bilateral lungs. A suspected multiflagellated protozoan was observed under a light microscope. But some different features were observed by electron microscopy, such as the orientation of flagella and nucleus. Besides, both bronchoalveolar lavage fluid and bronchoscopic brush smears underwent Gram staining and Pap staining, which revealed that numerous respiratory ciliated cells were scattered or accumulated in the sample.Finally, she was diagnosed with eosinophil pneumonia. Metronidazole,bronchodilators, and mucolytics were taken for 5 d and symptoms and pulmonary ventilation function improved. We herein report a case of chronic eosinophilic pneumonia, which was misdiagnosed as multiflagellated protozoan infection, and it is suggested that reliable diagnosis approaches are necessary,rather than clinical symptoms and morphological features.
文摘AIM:Intestinal parasitic diseases are commonly accompanied with diarrhoeal symptoms and allergic reactions.Eosinophilia occurs as a result of IL-5 synthesized from Th2 cells during allergic reactions.IL-5 acts as a factor activating eosinophils. The aim of this study was to compare the IL-5 cytokine measurements in serum samples and cell cultures.And also to compare eosinophilia observed in helminth infections and protozoon infections accompanied with allergy. METHODS:Twenty-three patients who presented with diarrhoeal symptoms and allergic complaints were tested positive for intestinal parasites,as well as 21 controls with allergic complaints who did not have any intestinal parasites were included in this study.IL-5 production in in vitro cell cultures prepared by using phytohemaglutinin (PHA) to stimulate peripheral blood mononuclear cells (PBMC) obtained from the blood samples taken from these patients were compared with the IL-5 level in serum.Furthermore, the IL-5 production in protozoon and helminth infections was also compared.Absolute eosinophil values in 1 mm^3 of blood were calculated by means of peripheral smear in both groups within the scope of the study. RESULTS:Parasites such as helminth detected in 15 (65.2%) and protozoon in 8 (34.8%) of the patients were included in this study.As regards the values of the sera in both patients with parasite infection and controls,the IL-5 production was found to be higher in the cell culture supernatant (P<0.001 and P<0.05).When the IL-5 level of the patients with helminth parasites was compared with that of those with protozoon,it was determined that the IL-5 level in serum was more significant in the patients with protozoon than in those with helminth (P<0.05).In the study group,the patients were found to have parasites, the percentage of eosinophil was 7.0% compared to 6.5% in the control group.Thus,there was no significant difference between the eosinophil values (P>0.05). CONCLUSION:It was found that IL-5 cytokine levels in serum samples from the patients with helminth and protozoon displayed more measurable values as compared to the IL-5 levels after stimulation with mitogen.It is concluded that IL-5 acts as a triggering factor in the toxiallergic complaints commonly seen in helminth and protozoon infections.
基金Supported by Deanship of Research,Jordan University of Science and Technology,No.214/2013
文摘AIM To investigate the putative role of protozoan parasites in the development of irritable bowel syndrome(IBS).METHODS The study included 109 IBS consecutive adult patients fulfilling the RomeⅢcriteria and 100 healthy control subjects.All study subjects filled a structured questionnaire,which covered demographic information and clinical data.Fresh stool samples were collected from patients and control subjects and processed within less than 2 h of collection.Iodine wet mounts and Trichrome stained smears prepared from fresh stool and sediment concentrate were microscopically examined for parasites.Blastocystis DNA was detected by polymerase chain reaction,and Cryptosporidium antigens were detected by ELISA.RESULTS A total of 109 IBS patients(31 males,78 females)with a mean age±SD of 27.25±11.58 years(range:16-60 years)were enrolled in the study.The main IBS subtype based on the symptoms of these patients was constipation-predominant(88.7%of patients).A hundred healthy subjects(30 males,70 females)with a mean±SD age of 25.0±9.13 years(range 18-66 years)were recruited as controls.In the IBS patients,Blastocystis DNA was detected in 25.7%,Cryptosporidium oocysts were observed in 9.2%,and Giardia cysts were observed in 11%.In the control subjects,Blastocystis,Cryptosporidium and Giardia were detected in 9%,0%,and 1%,respectively.The difference in the presence of Blastocystis(P=0.0034),Cryptosporidium(P=0.0003),and Giardia(P=0.0029)between IBS patients and controls was statistically significant by all methods used in this study.CONCLUSION Prevalence of Blastocystis,Cryptosporidium and Giardia is higher in IBS patients than in controls.These parasites are likely to have a role in the pathogenesis of IBS.
文摘Wastewater effluents containing phosphorus and nitrogen are major contributors to a variety of water pollution.The present study is therefore aimed at investigating the phosphate and nitrate removal efficiency of three wastewater protozoa(Aspidisca, Trachelophyllum and Peranema) in a laboratory-scale water treatment system.The system was made of two separate reactors(aerated and non-aerated) and
基金Supported by Shandong Provincial Natural Science Foundation,No.ZR2020QH138
文摘BACKGROUND Leishmaniasis includes a range of chronic infections in humans and animals and can be caused by more than 20 species of Leishmania protozoa.The manifestations of leishmaniasis are diverse and dependent on the immune response capacity of the host and the type of Leishmania.In East Asia,leishmaniasis is relatively rare and prone to misdiagnosis and underdiagnosis.CASE SUMMARY We report a case of a 36-year-old male with cutaneous leishmaniasis.The patient had been misdiagnosed with a bacterial skin infection and was given a dressing change and oral levofloxacin,which proved ineffective.Histopathological examination revealed amastigote(Leishman-Donovan body)in the histocytes,and nucleic acid sequencing proved that the pathogen was Leishmania major.The patient was treated successfully by regional injection of sodium gluconate(600 mg)three times.The ulcer healed and did not recur at 1.5-year follow-up.CONCLUSION Skin ulcers caused by leishmaniasis are easily misdiagnosed in non-epidemic countries,yet it should not be overlooked.
文摘Tritrichomonas foetus is a flagellate protozoan and the etiological agent of bovine genital tri-chomoniasis [1], which is an infectious vene- real disease. This parasite is usually found as- sociated with the mucosal surface of the uro- genital tract in females or the male preputial and penile membranes. In females, the clinical ma-nifestations may include abortion, with repe- tition of estrus at irregular intervals, vaginitis, cervicitis, endometritis, and pyometra. Parasi- tized males may have a discharge with small nodules in the preputial membrane. After that, the bulls have no clinical symptoms, and are thus an asymptomatic carrier that may spread the infection. Considering that a bull could cover up to twenty females [2], bovine genital trichomoniasis is a serious medical and veteri- nary problem, with economical repercussion for beef and milk production. As T. foetus is an amitochondrial and aerotolerant organism, en- ergy production under low O2 tension in the protozoan is done via hydrogenosome, which, as the name suggests, is the organelle where H2 is generated [3,4,5]. The molecular machinery of mitochondrial cell death is, therefore, absent in this parasite and the mechanism that activates of cell death program is not clear. This review seeks to understand the characteristics of the protozoan parasite T. foetus in order to propose new therapies for animals suffering from this infectious and contagious agent.
文摘The histological basis for acute osteocyte mechanosensitivity remains uncertain. A novel bone cell model of mechanotransduction and inorganic trafficking may be the powerful, silt-burrowing protozoan Spirostomum ambiguum which when being physically challenged fabricates within vesicles populations of bone-like calcium phosphate microspheres, about 1 μm in diameter. These not only attribute considerable compression-resilience but also resemble the Golgi-directed mineral assemblies we recently reported in osteocytes. Advantageously, calcification in the protozoan (confirmed by ultramicroscopy with EDX elemental microanalysis) enabled Golgi comparison under overt, natural phases of both high (i.e. silt-tunnelling) and low (i.e free-swimming) stress. Established hard-tissue microscopy techniques previously positive in bone cells included quantitative fluorescent tetracycline labelling for bone salt together with the same metazoan Golgi body marker (Green Fluorescent Protein-tagged mannosidase II construct). Organellar modulation was monitored by transfection of live organisms in situ (some post-stained with red nuclear fluorochrome TOPRO-3). Results showed that GFP-tagged Golgi fluorescence increased from swimmers (mean 74.5 ± SD 6.7 AU) to burrowers (mean 104.6 ± SD 2.7;p < 0.0001) synchronous with juxtanuclear tetracycline-labelled mineral fluorescence (swimmers, mean 89.7 ± SD 3.3 AU;burrowers, mean 138.0 ± SD 4.0;p < 0.0001). Intracellular dense microspheres, single or bridged, were harvested as pellets rich in Ca, P (Ca:P 0.98) and Si, their polarised alignment moving from transaxial in swimmers to axial in burrowers. It was concluded that Golgi-directed mineral fabrication in the large, accessible, silt-enclosed ciliate resembles that in the smaller, less-accessible bone cell and may be a conserved early mechanobiological intracellular development predicating force translation into compression-resistant mineral fabrication in loaded segments of the osteocyte syncitium.
基金The National Natural Science Foundation of China under contract Nos 31372504,41176115 and 41476118
文摘Vibrio harveyi, known as a pathogenic bacterium caused severe secondary bacterial infections of the large yellow croaker Larimichthys crocea, was identified as an endosymbiont in the marine parasitic ciliate protozoan Cryptocaryon irritans. Meta 16 S sequencing method was used to identify the bacterial flora in C. irritans, and V.harveyi was isolated via culture-dependent method. Vibrio harveyi was observed in cytoplasm of C. irritans at the stage of tomont both by transmission electron microscopy and by Fluorescence in situ hybridization; no signal,however, was detected in nucleus area. The relationship between V. harveyi and C. irritans and the role of endosymbiotic V. harveyi in C. irritans merit further investigation.
文摘A field study was conducted to evaluate the protozoan colonization patterns on artificial substrates in relation to organic pollution within a tropical harbour. The composition of protozoans and their succession rates on artificial substrates(polyurethane foam units) were compared between two field stations(A and B), and their presence were considered with regards to the prevailing water quality conditions at the study sites. Altogether 44 genera of flagellates and ciliates were documented. The common genera of flagellates encountered included Monas, Polytoma, and Chromalina. Among the ciliates, the predominant genera were Tetrahymena, Vorticella, Lagynophyra, and Heloiphyra. These groups exhibited characteristic successional patterns in relation to ambient water quality. At Station A, located close to the sewage outfall, the water quality parameters included poor Secchi disc transparency(0.48m), dissolved oxygen of 1.93 mg/ml, salinity of 18 psu, and temperature 31.3 ℃. Here, the nanoflagellates( spumella ) colonized first, followed by microcilliate( Tetrahymena ) and sessile form( Vorticella ). Station B, located on the seaward side, was characterized by relatively less stressed environmental conditions with transparency 1.85m and dissolved oxygen value of 6 04 mg/ml. Salinity of 27.27 psu, and mean temperature of 30 ℃ were recorded at “B'. At this station, the nanoflagellate Polytoma was first documented to colonize on the substrates, followed by microcilliate( Lagynophrya ) and suctorid( Heliophyra ). These findings support the use of protozoans as indicator species for evaluating the hazards posed by organic pollution to natural estuarine communities.
基金Supported by Consejo Nacional de Investigaciones Científicas y Técnicas,CONICET,PIP Nos.0032 and 11220120100619CO
文摘A correct antibody response requires the participation of both B and T lymphocytes and antigen presenting cells. In this review we address the role of follicular helper T lymphocytes(T FH) in this reaction. We shall focus on the regulation of their development and function in health and disease. T FH can be characterized on the basis of their phenotype and the pattern of secretion of cytokines. This fact is useful to study their participation in the generation of antibody deficiency in primary immunodeficiency diseases such as common variable immunodeficiency, X-linked hyper Ig M syndrome orX-linked lymphoproliferative disease. Increased numbers of T FH have been demonstrated in several autoimmune diseases and are thought to play a role in the development of autoantibodies. In chronic viral infections caused by the human immunodeficiency virus, hepatitis B or C virus, increased circulating T FH have been observed, but their role in the protective immune response to these agents is under discussion. Likewise, an important role of T FH in the control of some experimental protozoan infections has been proposed, and it will be important to assess their relevance in order to design effective vaccination strategies.
基金Supported by the National Key Research and Development Program of China(2022YFC3204703)the China Postdoctoral Innovation Talents Support Program(BX20230400).
文摘Intestinal infections affect approximately 450 million people globally,predominantly impacting children and immunocompromised individuals in lowand middle-income countries(LMICs)due to inadequate water,sanitation,and hygiene(WASH)conditions,poverty,malnutrition,and low literacy.In Kenya,the prevalence of intestinal infections is elevated by warm tropical climates and socioeconomic factors.This scoping review evaluates the national prevalence,risk factors,and contamination sources of intestinal protozoa in Kenya,using a One Health approach to synthesize existing data from various human,animal,and environmental studies.A comprehensive literature search identified 292 studies,of which 67 met the inclusion criteria,covering the period from 1966 to 2024.The review found that most studies utilized stool microscopy,a method with limited sensitivity,and largely focused on vulnerable human populations,with minimal investigation into environmental reservoirs.Key protozoa identified included Entamoeba histolytica,Cryptosporidium,and Giardia,with transmission driven by poor WASH conditions,environmental factors,and close humananimal interactions.The findings highlight significant gaps in environmental surveillance and suggest the need for a robust,integrated One Health approach to better understand and control protozoan infections in Kenya.
基金supported by the National Natural Science Foundation of China(project nos.42176145,42076113,and 31971519)in part by a grant from the Xiamen University Principal Fund Project(No.:20720200109 and 20720200106).
文摘The adaptive strategies of prey against predation risk have been pivotal in non-consumptive effects.However,the adaptive strategies of prey and the response mechanisms to various predation risk cues remain unclear.We hypothesized that prey adopt a similar adaptive strategy to address different predation risks,but their response mechanisms depend on the attributes of predation risk cues.To test this hypothesis,we used Didinium-Paramecium as a predator-prey model to first evaluate the effects of various predation risk cues,including homogenates of predators(TD)and prey(TP)alone or in combination(TM),and the density of conspecific prey on the specific growth rate(SGR)to determine their adaptive strategies and their underlying response mechanisms based on transcriptomic analysis.Our results show that predation risk cues considerably enhance prey SGR,with effects in descending order of TM,TD,and TP.However,such effects gradually decrease as the density of conspecific prey increases until they disappear.The trend in the levels of differentially expressed genes(DEGs)in prey exposed to different predation risk cues is similar to that of SGRs.In particular,pathways based on DEG enrichment mediated by predation risk cues involve cellular processes,nutrient metabolism,and synthesis of biological macromolecules.However,they differ in type,number,and location within specific biological processes.In conclusion,Paramecium uses early reproduction strategies to address the risk of predation caused by different cues,and differences in its response mechanisms depend on the attributes of the cues of predation risk,resulting in differences in the SGR of the prey.
文摘Melanization of shrimp gills is a general symptom in shrimp black bill diseases(sBG);therefore,the cause is not immediately apparent.This study aimed to determine the primary and secondary agents associated with a black gill outbreak in the Delvar complex in the Bushehr Province of Iran.During July and August of 2020,450 healthy and affected shrimps were collected based on brown to black gill color from three farms of the Bushehr Province in Iran.Characterization of pathogens was performed by gross signs,wet mounts,microbiological tests,histopathology methods,and sequencing of molecular markers.The mean weight and length of infected shrimps was significantly(P<0.05)lower than the healthy shrimps.The histological examination of sBG indicated the adhesion of secondary lamellae,accumulation of hemocyte cells at the end of the secondary lamellae,and necrosis of epithelial cells with pyknosis and karyorrhexis.According to our results,Aspergillus sydowii as a primary agent correlates with sBG disease in Litopenaeus vannamei from Iran,and other biotic factors,including bacterial(Vibrio owensii and V.parahaemolyticus)probably are secondary agents associated with sBG disease.
