ABSTRACT
BACKGROUND: Angiostrongyliasis is a zoonotic parasitic disease caused by the rat lungworm Angiostrongylus cantonensis. The intermediate hosts of A. cantonensis are gastropods, and snail species such as Pomacea canaliculata play a key role in the transmission of human angiostrongyliasis. Detecting A. cantonensis infection in snails is an important component of epidemiological surveillance and the control of angiostrongyliasis. METHODS: In this study, a new method for diagnosing A. cantonensis infection in gastropods was developed by recovering larvae from the buccal cavity of three snail species. The entire buccal cavity of a snail was extracted, and the tissue was pressed between two microscope slides to observe whether A. cantonensis larvae were present. Our new method was compared with traditional pathogenic detection methods of lung microscopy, tissue homogenization, and artificial digestion. We artificially infected 160 P. canaliculata, 160 Cipangopaludina chinensis, and 160 Bellamya aeruginosa snails with A. cantonensis. Then, the four different detection methods were used to diagnose infection in each snail species at 7, 14, 21, and 28 days post exposure. RESULTS: We found no significant difference in the percentages of infected P. canaliculata snails using the four methods to detect A. cantonensis larvae. The radula pressing method had a mean detection rate of 80%, while the lung microscopy (81.3%), tissue homogenization (83.8%), and artificial digestion (85%) methods had slightly greater detection rates. Similarly, the percentages of infected C. chinensis snails that were detected using the radula pressing (80%), tissue homogenization (82.1%), and artificial digestion (83.8%) methods were not significantly different. Finally, the percentages of infected B. aeruginosa snails that were detected using the radula pressing (81.3%), tissue homogenization (81.9%), and artificial digestion (81.4%) methods were not significantly different. These results showed that the radula pressing method had a similar detection rate to traditional lung microscopy, tissue homogenization, or artificial digestion methods. CONCLUSIONS: This study demonstrates a new method for the qualitative screening of gastropods that act as intermediate hosts of A. cantonensis (and other Angiostrongylus species), provides technical support for the control of human angiostrongyliasis, and furthers research on A. cantonensis.
Subject(s)
Angiostrongylus cantonensis , Larva , Snails , Strongylida Infections , Animals , Snails/parasitology , Strongylida Infections/diagnosis , Strongylida Infections/parasitology , Strongylida Infections/veterinary , Angiostrongylus cantonensis/isolation & purification , Angiostrongylus cantonensis/physiology , Mouth/parasitology , Angiostrongylus/isolation & purification , Angiostrongylus/physiology , Rats , HumansABSTRACT
BACKGROUND: Angiostrongyliasis is a highly dangerous infectious disease. Angiostrongylus cantonensis larvae migrate to the mouse brain and cause symptoms, such as brain swelling and bleeding. Noncoding RNAs (ncRNAs) are novel targets for the control of parasitic infections. However, the role of these molecules in A. cantonensis infection has not been fully clarified. METHODS: In total, 32 BALB/c mice were randomly divided into four groups, and the infection groups were inoculated with 40 A. cantonensis larvae by gavage. Hematoxylin and eosin (H&E) staining and RNA library construction were performed on brain tissues from infected mice. Differential expression of long noncoding RNAs (lncRNAs) and mRNAs in brain tissues was identified by high-throughput sequencing. The pathways and functions of the differentially expressed lncRNAs were determined by Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO) analyses. The functions of the differentially expressed lncRNAs were further characterized by lncRNAâmicroRNA (miRNA) target interactions. The potential host lncRNAs involved in larval infection of the brain were validated by quantitative real-time polymerase chain reaction (qRTâPCR). RESULTS: The pathological results showed that the degree of brain tissue damage increased with the duration of infection. The transcriptome results showed that 859 lncRNAs and 1895 mRNAs were differentially expressed compared with those in the control group, and several lncRNAs were highly expressed in the middle-late stages of mouse infection. GO and KEGG pathway analyses revealed that the differentially expressed target genes were enriched mainly in immune system processes and inflammatory response, among others, and several potential regulatory networks were constructed. CONCLUSIONS: This study revealed the expression profiles of lncRNAs in the brains of mice after infection with A. cantonensis. The lncRNAs H19, F630028O10Rik, Lockd, AI662270, AU020206, and Mexis were shown to play important roles in the infection of mice with A. cantonensis infection.
Subject(s)
Angiostrongylus cantonensis , Brain , Mice, Inbred BALB C , RNA, Long Noncoding , Strongylida Infections , Animals , RNA, Long Noncoding/genetics , RNA, Long Noncoding/metabolism , Angiostrongylus cantonensis/genetics , Strongylida Infections/parasitology , Strongylida Infections/genetics , Brain/parasitology , Brain/metabolism , Brain/pathology , Mice , Larva/genetics , MicroRNAs/genetics , MicroRNAs/metabolism , Gene Expression Profiling , Female , RNA, Messenger/genetics , RNA, Messenger/metabolismABSTRACT
Calcific aortic valve disease (CAVD) is a heart valve disorder characterized primarily by calcification of the aortic valve, resulting in stiffness and dysfunction of the valve. CAVD is prevalent among aging populations and is linked to factors such as hypertension, dyslipidemia, tobacco use, and genetic predisposition, and can result in becoming a growing economic and health burden. Once aortic valve calcification occurs, it will inevitably progress to aortic stenosis. At present, there are no medications available that have demonstrated effectiveness in managing or delaying the progression of the disease. In this study, we mined four publicly available microarray datasets (GSE12644 GSE51472, GSE77287, GSE233819) associated with CAVD from the GEO database with the aim of identifying hub genes associated with the occurrence of CAVD and searching for possible biological targets for the early prevention and diagnosis of CAVD. This study provides preliminary evidence for therapeutic and preventive targets for CAVD and may provide a solid foundation for subsequent biological studies.
Subject(s)
Aortic Valve Stenosis , Aortic Valve/pathology , Calcinosis , Heart Valve Diseases , Humans , Aortic Valve Stenosis/genetics , Aortic Valve Stenosis/diagnosis , Aortic Valve Stenosis/epidemiology , Heart Valve Diseases/genetics , Calcinosis/geneticsABSTRACT
The parasite Fasciola hepatica is an important zoonotic parasite. The development of an animal model of F. hepatica's life cycle is critical for studying the biological characteristics of the parasite in snails and mammals. Eggs of F. hepatica of bovine origin were cultured, and metacercariae were obtained after infection of Galba pervia snails. The life cycle system of F. hepatica was initiated in 2 different animals by orally infecting rabbits, SD rats and Kunming mice with the metacercariae. The animals' survival after infection, parasite migration in the animals and pathological damage to the liver were observed. We discovered that rabbits died due to acute suppurative hepatitis 6069 days after infection, and eggs were found in the feces on day 63 of infection. The liver of SD rats showed punctate lesions on day 3 of infection, and further changes occurred as the infection progressed. However, liver repair was observed at week 9. SD rats survived for more than a year after infection and continued the F. hepatica life cycle. The liver lesions in Kunming mice after infection were similar but more severe than those in SD rats. Death was observed on the 31st post-infection day. We discovered that while rabbits, SD rats and Kunming mice can all be used as animal models of F. hepatica, SD rats are more suitable experimental animals in terms of tolerance and pathological response.
Subject(s)
Fasciola hepatica , Fascioliasis , Animals , Cattle , Disease Models, Animal , Fasciola hepatica/physiology , Fascioliasis/parasitology , Life Cycle Stages , Mammals , Metacercariae , Mice , Rabbits , Rats , Rats, Sprague-DawleyABSTRACT
Sepsis is a systemic inflammatory response syndrome resulting from infection. This study aimed at exploring the role of microRNA-140 (miR-140) in septic mice. Wnt family member 11 (WNT11) was verified to be a target gene of miR-140 after bioinformatic prediction and dual luciferase reporter gene assay. Importantly, miR-140 negatively regulated WNT11. We initially induced the model of sepsis by endotoxin, and then ectopic expression and knockdown experiments were performed to explore the functional role of miR-140 in sepsis. Additionally, cross-sectional areas of muscle fiber, lactic acid production, 3-methylhistidine (3-MH) and tyrosine (Tyr) production in extensor digitorium longus (EDL) muscles, and serum levels of inflammatory factors were examined. The effect of miR-140 on the expression of WNT signaling pathway-related and apoptosis-related factors in skeletal muscle tissue was determined. The experimental results indicated that upregulated miR-140 or silenced WNT11 increased cross-sectional areas of muscle fiber while decreasing lactic acid production, skeletal muscle cell apoptosis [corresponding to downregulated B cell lymphoma 2 (Bcl-2)-associated X protein (Bax) and caspase-3 and upregulated Bcl-2], and the proteolytic rate of Tyr and 3-MH. Also, overexpressed miR-140 or silenced WNT11 reduced inflammation as reflected by decreased serum levels of IL-6, IL-10, and TNF-α. Furthermore, overexpression of miR-140 was shown to suppress the activation of the WNT signaling pathway, accompanied by decreased expression of WNT11, ß-catenin, and GSK-3ß. Taken together, upregulation of miR-140 could potentially inhibit skeletal muscle lactate release, an indirect measure of glycolysis, and atrophy in septic mice through suppressing the WNT signaling pathway via inhibiting WNT11 expression.
Subject(s)
Glycolysis , MicroRNAs/metabolism , Muscle, Skeletal/metabolism , Muscular Atrophy/metabolism , Sepsis/metabolism , Wnt Proteins/metabolism , Wnt Signaling Pathway , Animals , Apoptosis , Apoptosis Regulatory Proteins/metabolism , Cells, Cultured , Cytokines/blood , Disease Models, Animal , Down-Regulation , Glycogen Synthase Kinase 3 beta/genetics , Glycogen Synthase Kinase 3 beta/metabolism , Inflammation Mediators/blood , Lactic Acid/metabolism , Lipopolysaccharides , Male , Methylhistidines/metabolism , Mice, Inbred BALB C , MicroRNAs/genetics , Muscle, Skeletal/pathology , Muscular Atrophy/chemically induced , Muscular Atrophy/genetics , Muscular Atrophy/pathology , Sepsis/chemically induced , Sepsis/genetics , Sepsis/pathology , Tyrosine/metabolism , Wnt Proteins/genetics , beta Catenin/genetics , beta Catenin/metabolismABSTRACT
The Fasciola hepatica miracidia were used to infect 10 Galba pervia in a random manner. Beginning from day 44 after infection on which 10 metacercariae were found and a total of 495 metacercariae found in 24 days. No signs of cercaria escape or metacercaria formation in the early morning observed during 8 : 00-24 : 00, regardless of the environmental change. Metacercaria formation occurred mainly in the early morning. The metacercariae could attach to any object in water, but were easy to detach themselves. The findings suggest that F. hepatica cercaria escape and metacercaria formation mainly occur in the early morning in Dali.
Subject(s)
Fasciola hepatica , Metacercariae , Animals , Cercaria , WaterABSTRACT
OBJECTIVE: To determine the intermediate host of Fasciola hepatica in Dali of Yunnan Province, and investigate its development and characteristics. METHODS: F. hepatica eggs from cattle were collected from July 2012 to July 2013, and placed in 28 degrees C water bath for incubation. Galba pervia, Radix swinhoei, and Physa acuta were collected from Dali, and used to be infected with F. hepatica in the laboratory. Trematode infections were excluded from the snails before experiment. All the snails were infected with F. hepatica miracidia, reared in mud pots. Dead snails were dissected for observing the development of F. hepatica. The metacercariae were collected and identified by PCR amplification of partial sequence of mitochondrial cytochrome oxidase subunit I (COX1) gene. RESULTS: A total of 1 146 R. swinhoei, 996 P. acuta, and 3 307 G. pervia snails were infected with F. hepatica, respectively. Mother rediae were found in two R. swinhoei snails, but no child rediae were observed in the snails. No larval forms were found in P. acuta. G. pervia was infected by F. hepatica with an infection rate of 27.2% (900/3307). The miracidium escaped from the egg and penetrated into G. pervia at temperature 22 degrees C, developed into a sporocyst after 7-15 days, which transformed into mother redia at the 11 st-20th day post-infection. The mother redia developed into daughter redia at the 30th-37th day, and produced cercaria with longtail, and became metacercaria at the 42nd-55th day. PCR confirmed that the metacercariae were that of F. hepatica, with an obvious band (approximately 500 bp). CONCLUSION: Among the three potential intermediate hosts in Dali, G. pervia is experimentally infected with F. hepatica.
Subject(s)
Fasciola hepatica , Fascioliasis , Animals , Cattle , Cercaria , China , Larva , Snails , TemperatureABSTRACT
OBJECTIVE: To evaluate the molluscicidal effect of wettable powder of 50% niclosamide ethanolamide salt (WPN) and suspension concentrate of 26% metaldehyde and niclosamide (MNSC) on Lymnaea. METHODS: WPN and MNSC were prepared as a series of solutions containing the active ingredient concentrations of 0.06, 0.13, 0.25, 0.50, 1.00, 2.00 mg/L and 4.00 mg/L, and the adult Lymnaea snails were soaked in the above mentioned series of solutions in the laboratory, and the LC50 values were calculated. The doses of active ingredient concentrations of 0.03, 0.06, 0.13, 0.25, 0.50, 1.00 g/m2 and 2.00 g/m2 of WPN and MNSC were adopted to spray on Lymnaea snails in the laboratory, and the LC50 values were calculated. A series of solutions containing the active ingredient concentrations of 1.00 mg/L, 0.50 mg/L, 0.25 mg/L, and 0.13 mg/L of WPN and MNSC were prepared, and the adult Lymnaea snails were put into the bowls with each concentration solution above mentioned and the climbing situation of the snails was observed at different time. RESULTS: By the immersion method, LC50 values of WPN at 48 h and 72 h were 0.93 mg/L and 0.64 mg/L respectively; LC50 values of MNSC at 48 h and 72 h were 0.74 mg/L and 0.51 mg/L respectively; by the spray method, when active ingredient concentrations of WPN and MNSC were 1.00 g/m2 or more, the death rates were both 100% after 3 days. In the climbing test, the Lymnaea snails did not climb in the solutions containing the active ingredient concentration of 1.00 mg/L of WPN and MNSC, however, a few snails climbed in the low concentrations. CONCLUSIONS: WPN and MNSC both have the effect of killing Lymnaea snails and inhibiting their climbing. By using the immersion method in the field, the active ingredient concentration of 2.00 mg/L of WPN and MNSC for 48 h is appropriate; by using the spray method, the active ingredient content of 1.00 g/m2 of WPN and MNSC for 3 days is appropriate.
Subject(s)
Acetaldehyde/analogs & derivatives , Lymnaea , Molluscacides , Niclosamide , Animals , Dose-Response Relationship, Drug , Lymnaea/physiology , Movement/drug effects , Powders , Suspensions , Time FactorsABSTRACT
OBJECTIVE: To observe the number of eggs in the gravid proglottids of Taenia asiatica. METHODS: Twenty gravid proglottids at each end of two adults of T. asiatica were digested by 1% pepsin. Then, the collected eggs were observed and counted by a microscope. RESULTS: The number of eggs in each gravid proglottid were not the same, with the maximum of 132 500, minimum of 44 180, and the average number of 90 051, and there was a significant difference among the different gravid proglottids (t = -3.487, P = 0.003). CONCLUSION: The number of eggs in different gravid proglottids of T. asiatica is evidently different.