OBJECTIVE: To evaluate the protective effect of recombinant Schistosoma japonicum cystatin (rSj-Cys) against acute kidney injury induced by acute liver failure and unravel the underlying mechanism, so as to provide insights into the clinical therapy of acute kidney injury. METHODS: Twenty-four male C57BL/6J mice at ages of 6 to 8 weeks were randomly divided into the normal control group, rSj-Cys control group, lipopolysaccharide (LPS)/D-galactosamine (D-GaIN) model group and LPS/D-GaIN + rSj-Cys treatment group, of 6 mice each group. Mice in the LPS/D-GaIN group and LPS/D-GaIN + rSj-Cys group were intraperitoneally injected with LPS (10 μg/kg) and D-GaIN (700 mg/kg), and mice in the LPS/D-GaIN + rSj-Cys group were additionally administered with rSj-Cys (1.25 mg/kg) by intraperitoneal injection 30 min post-modeling, while mice in the rSj-Cys group were intraperitoneally injected with rSj-Cys (1.25 mg/kg), and mice in the normal control group were injected with the normal volume of PBS. All mice were sacrificed 6 h post-modeling, and mouse serum and kidney samples were collected. Serum creatinine (Cr) and urea nitrogen (BUN) levels were measured, and the pathological changes of mouse kidney specimens were examined using hematoxylin-eosin (HE) staining. Serum tumor necrosis factor (TNF)-α and interleukin (IL)-6 levels were detected using enzyme-linked immunosorbent assay (ELISA), and the expression of inflammatory factors and pyroptosis-related proteins was quantified in mouse kidney specimens using immunohistochemistry. In addition, the expression of pyroptosis-related proteins and nuclear factor-kappa B (NF-κB) signaling pathway-associated proteins was determined in mouse kidney specimens using Western blotting assay. RESULTS: HE staining showed no remarkable abnormality in the mouse kidney structure in the normal control group and the rSj-Cys control group, and renal tubular injury was found in LPS/D-GaIN group, while the renal tubular injury was alleviated in LPS/D-GaIN+rSj-Cys treatment group. There were significant differences in serum levels of Cr (F = 46.33, P < 0.001), BUN (F = 128.60, P < 0.001), TNF-α (F = 102.00, P < 0.001) and IL-6 (F = 202.10, P < 0.001) among the four groups, and lower serum Cr [(85.35 ± 32.05) μmol/L], BUN [(11.90 ± 2.76) mmol/L], TNF-α [(158.27 ± 15.83) pg/mL] and IL-6 levels [(56.72 ± 4.37) pg/mL] were detected in the in LPS/D-GaIN + rSj-Cys group than in the LPS/D-GaIN group (all P values < 0.01). Immunohistochemical staining detected significant differences in TNF-α (F = 24.16, P < 0.001) and IL-10 (F = 15.07, P < 0.01) expression among the four groups, and lower TNF-α [(106.50 ± 16.57)%] and higher IL-10 expression [(91.83 ± 5.23)%] was detected in the LPS/D-GaIN + rSj-Cys group than in the LPS/D-GaIN group (both P values < 0.01). Western blotting and immunohistochemistry detected significant differences in the protein expression of pyroptosis-related proteins NOD-like receptor thermal protein domain associated protein 3 (NLRP3) (F = 24.57 and 30.72, both P values < 0.001), IL-1β (F = 19.24 and 22.59, both P values < 0.001) and IL-18 (F = 16.60 and 19.30, both P values < 0.001) in kidney samples among the four groups, and lower NLRP3, IL-1β and IL-18 expression was quantified in the LPS/D-GaIN + rSj-Cys treatment group than in the LPS/D-GaIN group (P values < 0.05). In addition, there were significant differences in the protein expression of NF-κB signaling pathway-associated proteins p-NF-κB p-P65/NF-κB p65 (F = 71.88, P < 0.001), Toll-like receptor (TLR)-4 (F = 45.49, P < 0.001) and p-IκB/IκB (F = 60.87, P < 0.001) in mouse kidney samples among the four groups, and lower expression of three NF-κB signaling pathway-associated proteins was determined in the LPS/D-GaIN + rSj-Cys treatment group than in the LPS/D-GaIN group (all P values < 0.01). CONCLUSIONS rSj-Cys may present a protective effect against acute kidney injury caused by acute liver failure through inhibiting inflammation and pyroptosis and downregulating the NF-κB signaling pathway.
Mice ; Male ; Animals ; Interleukin-10 ; Tumor Necrosis Factor-alpha/genetics* ; NF-kappa B/therapeutic use* ; Interleukin-18/therapeutic use* ; Schistosoma japonicum/metabolism* ; Interleukin-6/therapeutic use* ; Lipopolysaccharides/therapeutic use* ; NLR Family, Pyrin Domain-Containing 3 Protein ; Mice, Inbred C57BL ; Acute Kidney Injury/drug therapy* ; Liver Failure, Acute ; Cystatins/therapeutic use*

OBJECTIVE: To evaluate the molluscicidal activity of surfactin against Oncomelania hupensis, so as to provide the experimental basis for use of Bacillus for killing O. hupensis. METHODS: O. hupensis snails were collected from schistosomiasisendemic foci of Wuhu City on September 2022, and Schistosoma japonicum-infected snails were removed. Then, 60 snails were immersed in surfactin at concentrations of 2, 1, 0.5, 0.25, 0.125 mg/mL and 0.062 5 mg/mL for 24, 48, 72 hours at 26 °C, while ultrapure water-treated snails served as controls. The median lethal concentration (LC₅₀) of surfactin against O. hupensis snails was estimated. O. hupensis snails were immersed in surfactin at a concentration of 24 h LC₅₀ and ultrapure water, and then stained with propidium iodide (PI). The PI uptake in haemocyte was observed in O. hupensis snails using fluorescence microscopy. RESULTS: The mortality of O. hupensis was 5.0% following immersion in surfactin at a concentration of 0.062 5 mg/mL for 24 h, and the mortality was 100.0% following immersion in surfactin at a concentration of 2 mg/mL for 72 h, while no snail mortality was observed in the control group. There were significant differences in the mortality of O. hupensis in each surfactin treatment groups at 24 (χ² = 180.150, P < 0.05), 48 h (χ² = 176.786, P < 0.05) and 72 h (χ² = 216.487, P < 0.05), respectively. The average mortality rates of O. hupensis were 38.9% (140/360), 62.2% (224/360) and 83.3% (300/360) 24, 48 h and 72 h post-immersion in surfactin, respectively (χ² = 150.264, P < 0.05), and the 24, 48 h and 72 h LC₅₀ values of surfactin were 0.591, 0.191 mg/mL and 0.054 mg/mL against O. hupensis snails. Fluorescence microscopy showed more numbers of haemocytes with PI uptake in 0.5 mg/mL surfactintreated O. hupensis snails than in ultrapure water-treated snails for 24 h, and there was a significant difference in the proportion of PI uptake in haemocytes between surfactin-and ultrapure water-treated snails (χ² = 6.690, P < 0.05). CONCLUSIONS Surfactin is active against O. hupensis snails, which may be associated with the alteration in the integrity of haemocyte membrane.
Animals ; Molluscacides/pharmacology* ; Snails ; Schistosoma japonicum ; Lethal Dose 50 ; Water

OBJECTIVE: To investigate the spatial distribution characteristics of the prevalence of advanced schistosomiasis and seroprevalence of anti-Schistosoma antibody, and to examine the correlation between the prevalence of advanced schistosomiasis and seroprevalence of anti-Schistosoma antibody in Hunan Province in 2020, so as to provide insights into advanced schistosomiais control in the province. METHODS: The epidemiological data of schistosomiasis in Hunan Province in 2020 were collected, including number of permanent residents in survey villages, number of advanced schistosomiasis patients, number of residents receiving serological tests and number of residents seropositive for anti-Schistosoma antibody, and the prevalence advanced schistosomiasis and seroprevalence of anti-Schistosoma antibody were descriptively analyzed. Village-based spatial distribution characteristics of prevalence advanced schistosomiasis and seroprevalence of anti-Schistosoma antibody were identified in Hunan Province in 2020, and the correlation between the revalence advanced schistosomiasis and seroprevalence of anti-Schistosoma antibody was examined using Spearman correlation analysis. RESULTS: The prevalence of advanced schistosomiasis was 0 to 2.72% and the seroprevalence of anti-Schistosoma antibody was 0 to 20.25% in 1 153 schistosomiasis-endemic villages in Hunan Province in 2020. Spatial clusters were identified in both the prevalence of advanced schistosomiasis (global Moran's I = 0.416, P < 0.01) and the seroprevalence of anti-Schistosoma antibody (global Moran's I = 0.711, P < 0.01) in Hunan Province. Local spatial autocorrelation analysis identified 98 schistosomiasis-endemic villages with high-high clusters of the prevalence of advanced schistosomiasis, 134 endemic villages with high-high clusters of the seroprevalence of anti-Schistosoma antibody and 36 endemic villages with high-high clusters of both the prevalence of advanced schistosomiasis and seroprevalence of anti-Schistosoma antibody in Hunan Province. In addition, spearman correlation analysis showed a positive correlation between the prevalence of advanced schistosomiasis and seroprevalence of anti-Schistosoma antibody (r_s = 0.235, P < 0.05). CONCLUSIONS There were spatial clusters of the prevalence of advanced schistosomiasis and seroprevalence of anti-Schistosoma antibody in Hunan Province in 2020, which were predominantly located in areas neighboring the Dongting Lake. These clusters should be given a high priority in the schistosomiasis control programs.
Animals ; Humans ; Prevalence ; Seroepidemiologic Studies ; Schistosomiasis/epidemiology* ; Schistosoma ; Spatial Analysis ; Antibodies, Helminth ; China/epidemiology*

OBJECTIVE: To evaluate the performance of recombinase-aided amplification (RAA) assay in detection of Clonorchis sinensis metacercariae in freshwater fish samples, so as to provide insights into standardization and field application of this assay. METHODS: Wild freshwater fish samples were collected in the rivers of administrative villages where C. sinensis-infected residents lived in Jiangyan District, Xinghua County and Taixing County of Taizhou City, Jiangsu Province from June to September 2022. Genomic DNA was extracted from six freshwater fish specimens (5 g each) containing 0, 1, 2, 4, 8 and 16 C. sinensis metacercariae for fluorescent RAA assay, and the diagnostic sensitivity was evaluated. Fluorescent RAA assay was performed with genomic DNA from C. sinensis, Metorchis orientalis, Haplorchis pumilio and Centrocestus formosanus metacercariae as templates to evaluate its cross-reactions. In addition, the detection of fluorescent RAA assay and direct compression method for C. sinensis metacercariae was compared in field-collected freshwater fish samples. RESULTS: Positive amplification was found in fresh-water fish specimens containing different numbers of C. sinensis metacercariae, and fluorescent RAA assay was effective to detect one C. sinensis metacercaria in 5 g freshwater fish specimens within 20 min. Fluorescent RAA assay tested negative for DNA from M. orientalis, H. pumilio and C. formosanus metacercariae. Fluorescent RAA assay and direct compression method showed 5.36% (93/1 735) and 2.88% (50/1 735) detection rates for C. sinensis metacercariae in 1 735 field-collected freshwater fish samples, with a statistically significant difference seen (χ² = 478.150, P < 0.001). There was a significant difference in the detection of C. sinensis metacercariae in different species of freshwater fish by both the direct compression method (χ² = 11.20, P < 0.05) and fluorescent RAA assay (χ² = 20.26, P < 0.001), and the detection of C. sinensis metacercariae was higher in Pseudorasbora parva than in other fish species by both the direct compression method and fluorescent RAA assay (both P values < 0.05). CONCLUSIONS Fluorescent RAA assay has a high sensitivity for detection of C. sinensis metacercariae in freshwater fish samples, and has no cross-reactions with M. orientalis, H. pumilio or C. formosanus metacercariae. Fluorescent RAA assay shows a higher accuracy for detection of C. sinensis infections in field-collected freshwater fish than the direct compression method.
Animals ; Clonorchis sinensis/genetics* ; Metacercariae/genetics* ; Recombinases ; Fresh Water ; Fishes ; DNA ; Fish Diseases/diagnosis*

OBJECTIVE: To establish a surveillance and early warning index system for schistosomiasis transmission risk along the middle and lower reaches of the Yangtze River basin, so as to provide insights into creation of a sensitive and highly efficient surveillance and early warning system for schistosomiasis. METHODS: National and international publications, documents, laws and regulations pertaining to schistosomiasis control were retrieved with keywords including schistosomiasis, surveillance, early warning and control interventions from 2008 to 2022, and a thematic panel discussion was held to preliminarily construct surveillance and early warning index system for schistosomiasis transmission risk along the middle and lower reaches of the Yangtze River basin. The index system was then comprehensively scored and screened using the Delphi method, and the weight of each index was determined using analytic hierarchy process and the modified proportional allocation method. In addition, the credibility of the Delphi method was evaluated using positive coefficient, authority coefficient, degree of concentration and degree of coordination of experts. RESULTS: Following two rounds of expert consultation, a surveillance and early warning index system for schistosomiasis transmission risk in endemic areas along the middle and lower reaches of the Yangtze River basin was preliminarily constructed, including 3 primary indicators, 9 secondary indicators and 41 tertiary indicators. The normalized weights of primary indicators epidemics, natural and social factors and comprehensive control were 0.639 8, 0.145 6 and 0.214 6, respectively, and among all secondary indicators, snail status (0.321 3) and schistosomiasis prevalence (0.318 5) had the highest combined weights, while social factors had the lowest combined weight (0.030 4). Of all tertiary indicators, human egg-positive rate (0.041 9), number of acute schistosomiasis cases (0.041 5), number of stool-positive bovine and sheep (0.041 1), and prevalence of Schistosoma japonicum in free-ranging livestock (0.041 1) had the highest combined weights. During two rounds of consultation, the positive coefficient of experts was both 100%, and the authority coefficient was both 0.9 and greater, while the coordination coefficients were 0.338 to 0.441 and 0.426 to 0.565 (χ² = 22.875 to 216.524, both P values < 0.05). CONCLUSIONS The established surveillance and early warning index system for schistosomiasis transmission risk along the middle and lower reaches of the Yangtze River basin is of great scientific values and authority, which may provide insights into construction of the sensitive and highly efficient surveillance and early warning system for schistosomiasis in the context of low prevalence and low intensity of infection in China.
Animals ; Cattle ; Humans ; Sheep ; Rivers ; Schistosomiasis/prevention & control* ; Schistosoma japonicum ; China/epidemiology* ; Snails

OBJECTIVE: To investigate the sequences of internal transcribed spacer 2 (ITS2) and cyclooxygenase 1 (COX1) genes of Paragonimus metacercariae in freshwater crabs in Henan Province, identify the species of Paragonimus and evaluate its genetic relationships with Paragonimus isolates from other provinces in China. METHODS: Freshwater crabs were collected from 8 survey sites in Zhengzhou, Luoyang, Pingdingshan, Nanyang and Jiyuan cities of Henan Province from 2016 to 2021, and Paragonimus metacercariae were detected in freshwater crabs. Genomic DNA was extracted from Paragonimus metacercariae, and the ITS2 and COX1 genes were amplified using PCR assay, followed by sequencing of PCR amplification products. The gene sequences were spliced and aligned using the software DNASTAR, and aligned with the sequences of Paragonimus genes in the GenBank. Phylogenetic trees were created using the MEGA6 software with the Neighbor-Joining method based on ITS2 and COX1 gene sequences, with Fasciola hepatica as the outgroup. RESULTS: The detection rates of Paragonimus metacercariae were 6.83% (11/161), 50.82% (31/61), 18.52% (5/26), 8.76% (12/137), 14.29% (9/63), 17.76% (19/105), 18.50% (32/173) and 42.71% (41/96) in freshwater crabs from 8 survey sites in Zhengzhou, Luoyang, Pingdingshan, Nanyang and Jiyuan cities of Henan Province, with a mean detection rate of 19.46% (160/822), and a mean infection intensity of 0.57 metacercariae/g. The amplified ITS2 and COX1 gene fragments of Paragonimus were approximately 500 bp and 450 bp in lengths, respectively. The ITS2 gene sequences of Paragonimus metacercariae from 8 survey sites of Henan Province showed the highest homology (99.8% to 100.0%) with the gene sequence of P. skrjabini (GenBank accession number: MW960209.1), and phylogenetic analysis showed that the Paragonimus in this study was clustered into the same clade with P. skrjabini from Sichuan Province (GenBank accession number: AY618747.1), Guangxi Zhuang Autonomous Region (GenBank accession number: AY618729.1) and Hubei Province (GenBank accession number: AY618751.1), and P. miyazaki from Fujian Province (GenBank accession number: AY618741.1) and Japan (GenBank accession number: AB713405.1). The COX1 gene sequences of Paragonimus metacercariae from 8 survey sites of Henan Province showed the highest homology (90.0% to 100.0%) with the gene sequence of P. skrjabini (GenBank accession number: AY618798.1), and phylogenetic analysis showed that the Paragonimus in this study was clustered into the same clade with all P. skrjabini and clustered into the same sub-clade with P. skrjabini from Hubei Province (GenBank accession numbers: AY618782.1 and AY618764.1). CONCLUSIONS Paragonimus species from freshwater crabs in Henan Province were all characterized as P. skrjabini, and the ITS2 and COX1 gene sequences had the highest homology to those of P. skrjabini from Hubei Province. The results provide insights into study of Paragonimus in Henan Province and China.
Animals ; Paragonimus/genetics* ; Brachyura/genetics* ; Cyclooxygenase 1/genetics* ; Phylogeny ; China/epidemiology* ; Sequence Analysis, DNA ; Paragonimiasis

Schistosomiasis is still a public health burden in the Philippines. Chronic infection with Schistosoma japonicum, the only species endemic in the Philippines, clinically manifests itself in a wide variety of pathologies usually correlated with the anatomical site of adult worm activity and deposition of eggs. One of the documented ectopic sites for Schistosoma ova is the appendix. A rare sequela of this is acute appendicitis and an even rarer consequence is progression to appendiceal rupture leading to acute peritonitis. We present a case of a 27-year-old Filipino residing in Davao City but born in Agusan Province who initially complained of right lower quadrant abdominal pain but presented at the emergency room with generalized abdominal tenderness with signs of peritoneal irritation. Exploratory laparotomy with an infraumbilical incision revealed ruptured appendicitis with periappendiceal abscess formation and appendectomy was subsequently done. Schistosoma infection of the appendix was subsequently established by histopathological analysis. Furthermore, features observed suggest an atypical pathogenetic process contrary to the putative pathogenesis of most cases of acute appendicitis.
Schistosomiasis ; Schistosoma japonicum

Animals ; Schistosoma japonicum ; Colitis, Ulcerative

Oncomelania hupensis is the only intermediate host of Schistosoma japonicum, and O. hupensis control is an important measure for schistosomiasis control. With the progress of national schistosomiasis control program, the prevalence of schistosomiasis is low in China; however, there are still multiple challenges for O. hupensis breeding and schistosomiasis transmission risk. Considering the target of the national schistosomiasis elimination program and environmental protection in the new era, the introduction of precision identification, precision interventions and precision assessment into O. hupensis control may facilitate the progress towards elimination of schistosomiasis in China.
Animals ; China/epidemiology* ; Schistosoma japonicum ; Schistosomiasis/prevention & control* ; Snails

OBJECTIVE: To analyze the spatial-temporal distribution characteristics of Oncomelania hupensis snails in Anhui Province from 2011 to 2020, to provide insights into precision control of O. hupensis snails in Anhui Province. METHODS: O. hupensis snail distribution data were collected in Anhui Province from 2011 to 2020 and descriptively analyzed, including actual area of snail habitats, area of emerging snail habitats and area of Schistosoma japonicum-infected snails. The actual area of snail habitats and area of emerging snail habitats were subjected to spatial autocorrelation analysis, hotspot analysis, standard deviation ellipse analysis and space-time scanning analysis, and the clusters of snail distribution and settings at high risk of snail spread were identified in Anhui Province from 2011 to 2020. RESULTS: The actual area of snail habitats gradually decreased in Anhui Province from 2011 to 2020. The actual area of snail habitats were 26 238.85 hm² in Anhui Province in 2020, which were mainly distributed in marshland and lake regions. There was a large fluctuation in the area of emerging snail habitats in Anhui Province during the period from 2011 to 2020, with the largest area seen in 2016 (1 287.65 hm²), and 1.96 hm² emerging infected snail habitats were detected in Guichi District, Chizhou City in 2020. Spatial autocorrelation and hotspot analyses showed spatial clusters in the distribution of actual areas of snail habitats in Anhui Province from 2011 to 2020 (Z = 3.00 to 3.43, all P values < 0.01), and the hotspots were mainly concentrated in the marshland and lake regions and distributed along the south side of the Yangtze River, while the cold spots were mainly concentrated in the mountainous regions of southern Anhui Province. There were no overall spatial clusters in the distribution of areas of emerging snail habitats (Z = -2.20 to 1.71, all P values > 0.05), and a scattered distribution was found in local regions. Standard deviation ellipse analysis showed relatively stable distributions of the actual areas of snail habitats in Anhui Province from 2011 to 2020, which was consistent with the flow direction of the Yangtze River, and the focus of the distribution of areas of emerging snail habitats shifted from the lower reaches to upper reaches of Anhui section of the Yangtze River. Space-time scanning analysis identified two high-value clusters in the distribution of actual areas of snail habitats in lower and middle reaches of Anhui section of the Yangtze River from 2011 to 2020, and two high-value clusters in the distribution of areas of emerging snail habitats were identified in mountainous and hilly regions. CONCLUSIONS There were spatial clusters in the distribution of O. hupensis snails in Anhui Province from 2011 to 2020, which appeared a tendency of aggregation towards the south side and upper reaches of the Yangtze River; however, the spread of O. hupensis snails could not be neglected in mountainous and hilly regions. Monitoring of emerging snail habitats should be reinforced in mountainous and hilly regions and along the Yangtze River basin.
Animals ; China/epidemiology* ; Ecosystem ; Gastropoda ; Lakes ; Rivers ; Schistosoma japonicum