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1.
Germline KLLN promoter hypermethylation was recently identified as a potential genetic etiology of the cancer predisposition syndrome, Cowden syndrome (CS), when no causal PTEN gene mutation was found. We screened for KLLN promoter methylation in a large prospective series of CS patients and determined the risk of benign and malignant CS features in patients with increased methylation both with and without a PTEN mutation/variant of unknown significance. In all, 1012 CS patients meeting relaxed International Cowden Consortium criteria including 261 PTEN mutation-positive CS patients, 187 PTEN variant-positive CS patients and 564 PTEN mutation-negative CS patients, as well as 111 population controls were assessed for germline KLLN promoter methylation by MassARRAY EpiTYPER analysis. KLLN promoter methylation was analyzed both as a continuous and a dichotomous variable in the calculation of phenotypic risks by stepwise logistic regression and Kaplan–Meier/standardized incidence ratio methods, respectively. Significantly increased KLLN promoter methylation was seen in CS individuals with and without a PTEN mutation/VUS compared with controls (P<0.001). Patients with high KLLN promoter methylation have increased risks of all CS-associated malignancies compared with the general population. Interestingly, KLLN-associated risk of thyroid cancer appears to be gender and PTEN status dependent. KLLN promoter methylation associated with different benign phenotypes dependent on PTEN status. Furthermore, increasing KLLN promoter methylation is associated with a greater phenotype burden in mutation-negative CS patients. Germline promoter hypermethylation of KLLN is associated with particular malignant and benign CS features, which is dependent on the PTEN mutation status.  相似文献   

2.
The incidence of non-thermophilic Campylobacter species was assessed in an unselected population-based study in a mixed urban and rural community in North Jutland, Denmark. In a 2-year study period, 11 314 faecal samples from 8302 patients with gastroenteritis were cultured with supplement of the filter method. We recovered a high incidence of Campylobacter concisus (annual incidence 35/100 000 inhabitants), almost as high as the common Campylobacter jejuni/coli. In contrast, there was a very low incidence of other non-thermophilic Campylobacter species, such as Campylobacter upsaliensis. Campylobacter concisus was, unlike C. jejuni/coli, found more frequently among small children (<1 year) and the elderly (≥65 years). Around 10% of the patients with C. consisus had co-infections dominated by Clostridium difficile and Salmonella enterica, whereas co-infections occurred in about 5% of C. jejuni/coli patients. We observed a seasonal variation in C. jejuni/coli with a peak incidence in late summer months and autumn, whereas there was an almost constant monthly prevalence of C. concisus. Among patients participating in a questionnaire sub-study, there was a higher degree of close contacts with animals, especially dogs, as well as a higher travel exposure among C. jejuni/coli patients compared with C. concisus patients. We did not culture any C. concisus in stool samples from a small cohort of healthy individuals. Future studies have to focus on the clinical follow-up and the long-term risk of inflammatory bowel diseases in C. concisus-positive patients. We conclude that there is a high incidence of C. concisus in Denmark.  相似文献   

3.
There is a clear need for the development of a rapid and reliable test for the identification of Candida dubliniensis and for the discrimination of this species from Candida albicans. In the present study we have investigated the potential use of C. dubliniensis-specific antigens as a basis for its identification. We produced an anti-C. dubliniensis serum which, after adsorption with C. albicans blastospores, was found to differentially label C. dubliniensis isolates in an indirect immunofluorescence test. In this test, the antiserum reacted with blastospores and germ tubes of C. dubliniensis and with blastospores of Candida krusei and Rhodotorula rubra but did not react with blastospores of several other Candida species including C. albicans. The antiserum also reacted with C. albicans germ tubes. The anti-C. dubliniensis adsorbed serum reacted with specific components of 25, 28, 37, 40, 52, and 62 kDa in the C. dubliniensis extract and with a variety of antigens from other yeast species. The antigens from non-C. dubliniensis yeasts showing reactivity with the anti-C. dubliniensis adsorbed serum are mostly expressed within the cell walls of these yeast species, and this reactivity does not interfere with the use of the anti-C. dubliniensis adsorbed serum in an indirect immunofluorescence test for the rapid identification of C. dubliniensis.  相似文献   

4.
Walker–Warburg syndrome (WWS) is a severe muscular dystrophy with eye and brain malformations. On a molecular level, WWS is a disorder of the O-linked glycosylation of α-dystroglycan and therefore referred to as one of the dystroglycanopathies. The disease family of muscular dystrophy–dystroglycanopathy (MDDG) contains a spectrum of severe to mild disorders, designated as MDDG type A to C. WWS, as the most severe manifestation, corresponds to MDDG type A. Defects in the genes POMT1, POMT2, POMGNT1, FKTN, FKRP, LARGE, GTDC2, G3GALNT2, GMPPB, B3GNT1, TMEM5 and COL4A1 and ISPD have been described as causal for several types of MDDG including WWS, but can only be confirmed in about 60–70% of the clinically diagnosed individuals. The proteins encoded by these genes are involved in the posttranslational modification of α-dystroglycan. Mutations in POMT1, POMT2, POMGNT1, FKTN, FKRP, LARGE, GMPPB, TMEM5 and COL4A1 and ISPD lead to a wide spectrum of phenotypes of congenital muscular dystrophies with or without eye and brain abnormalities. Patients with WWS frequently demonstrate a complete lack of psychomotor development, severe eye malformations, cobblestone lissencephaly and a hypoplastic cerebellum and brainstem, seizures, hydrocephalus and poor prognosis. Here, we present a boy with WWS who showed compound heterozygous changes in ISPD and discuss the clinical and radiological phenotype and the molecular genetic findings, including a novel pathogenic mutation in ISPD.  相似文献   

5.
Epidemiological data on staphylococcal scalded skin syndromes (SSSS), including bullous impetigo (BI) and generalized exfoliative syndrome (GES), are scarce. To better characterize SSSS and associated Staphylococcus aureus strains, we conducted a retrospective study of 349 cases collected in France between 1997 and 2007 by the National Reference Centre of Staphylococci. Our results showed a stationary evolution of SSSS cases, with a heterogeneous distribution of cases in France. Although notification was not exhaustive, we estimated an incidence of 0.56 cases/year/million inhabitants, in accordance with previous studies conducted in France and Europe, with a median age of 2 years old and sex ratios of 1. A seasonal effect was observed, with a higher GES/BI ratio in autumn compared with other seasons, which could be explained by the impact of viral co-infection. Genetic analysis of S. aureus strains showed that accessory gene regulator (agr) 4, exfoliative toxin A (eta) and B (etb) genes, staphylococcal and enterotoxin-like O (selo) gene and agr4 etb selo profiles were predominantly associated with GES, whereas agr2 eta and agr4 eta selo were more frequently observed with BI. Only one methicillin-resistant strain was found. Protein A (spa) typing identified two main genotypes: spa clonal complex (CC) 159/sequence-type (ST) 121 (75%) and spaCC346/ST15 (18%). spaCC159 was mainly associated with agr4 eta etb selo, agr4 eta selo and agr4 etb selo, and spaCC346 was mainly associated with agr2 eta, suggesting that French SSSS cases are caused by these two main lineages. However, in a multivariate analysis, only etb was independently associated with GES.  相似文献   

6.
Seven serotypes of Streptococcus mutans have been identified. The biochemical, genetic, and serological characteristics of these serotypes have indicated that certain serotypes are quite similar, whereas others are quite distinct. The effect of local immunization with glucosyltransferase (GTF) enzymes from serotypes a, c, or g on infection and disease caused by homologous or heterologous cariogenic S. mutans is reported. Organisms with either similar (a and g) or different (c and g) biochemical and serological characteristics were selected for heterologous challenge. NIH white hamsters were injected four times at weekly intervals with GTF prepared by 6 M guanidine-hydrochloride elution from water-insoluble glucan of serotypes a, c, or g, which resulted in enzyme (homologous) inhibitory activity in sera and salivas. After infection of GTF-immunized and sham-immunized groups of hamsters with cariogenic S. mutans of the same serotype as the injected antigen (homologous infection) or with S. mutans of a different serotype from the injected antigen (heterologous infection), the numbers of streptomycin-labeled S. mutans, caries, and lesions were determined. Immunization with GTF preparations from each of the three serotypes resulted in statistically significant reductions in the extent of infection and disease and number of lesions caused by infections with homologous cariogenic S. mutans. Statistically significant reductions in these three parameters were also observed in groups immunized with enzyme from serotype a (strain E49) and challenged with cariogenic serotype g (strain 6715) organisms; or immunized with enzyme from serotype c (strain Ingbritt) and challenged with cariogenic serotype g (strain 6715) organisms; or immunized with enzyme from serotype g (strain 6715) and challenged with cariogenic serotype c (strain Ingbritt) organisms. These studies suggest that soluble antigen preparations containing GTF from one serotype may elicit a protective immune response against infection with cariogenic S. mutans from many or possibly all serotypes.  相似文献   

7.
The prognosis of myeloproliferative neoplasms, including primary myelofibrosis (PMF), polycythemia vera, and essential thrombocythemia varies considerably, between these disorders as well as within each diagnosis. Molecular studies have identified “driver mutations” in JAK2, MPL1, and CALR and additional somatic DNA mutations, including ASXL1, EZH2, IDH1/2, and SRSF2, that affect prognosis differentially. Patients with mutations in CALR (type1) have a better outlook than patients with mutations in JAK2 or MPL, whereas patients without any of the driver mutations (triple negative) have the shortest life expectancy. Mutations in ASXL1, EZH2, and SRSF2 may be associated with shortened survival, and IDH mutations carry a higher risk of leukemic transformation. The combination and number of mutations are more important than a given single mutation. Mutations also appear to impact the outcome of hematopoietic cell transplantation (HCT), currently the only treatment with curative potential. Based on available data, the best post-HCT outcome is observed with CALR mutations. Triple negativity has a negative impact. The data on JAK2 are controversial. Mutations in ASXL1 or IDH1/2 reduce the probability of progression-free survival after HCT, although the impact of ASXL1 differs between patients with primary and secondary myelofibrosis. Although it is not clear to what extent HCT can overcome the risks associated with a given mutational pattern, at present, early HCT should be considered in triple-negative patients and patients with PMF who harbor mutations in ASXL1. Mutations in EZH2, SRSF2, or IDH, particularly if combined with other mutations, should also lead to consideration of HCT. Further studies are needed to validate the present observations and determine the impact of additional mutations that have been identified.  相似文献   

8.
The aim of the study was to assess the effect of the association of entomopathogenic nematodes and fungi on Rhipicephalus microplus. The nematodes used were Heterorhabditis bacteriophora HP88 and Heterorhabditis indica LPP1 and the fungi were Metarhizium anisopliae IBCB 116 and Beauveria bassiana ESALQ 986. In the groups treated with the fungi, the females were immersed for 3 min in a conidial suspension, while in the groups treated with the nematodes, the ticks were exposed to infective juveniles. To evaluate the interaction between entomopathogens, the females were first immersed in a conidial suspension and then exposed to the nematodes. The egg mass weight and hatching percentage values of the groups treated with M. anisopliae IBCB 116 and B. bassiana ESALQ 986 in the two experiments were statistically similar (p?>?0.05) to the values of the control group. In the groups treated only with nematodes, there was a significant reduction (p?<?0.05) in the egg mass weight, a fact also observed for the hatching percentage of the group treated with H. indica LPP1. In all the groups treated with nematodes in association with fungi, there was a significant reduction (p?<?0.05) in the egg mass weight and hatching percentage. The percentage of control of the groups treated with fungi alone varied from 31 to 55 %. In the groups treated with nematodes associated or not with fungi, the control percentage was always greater than 90 % and reached 100 % in the group treated with H. bacteriophora HP88 associated with the fungus M. anisopliae IBCB 116.  相似文献   

9.
Tuberous Sclerosis Complex (TSC) is a multisystemic condition caused by mutations in TSC1 or TSC2, but a pathogenic variant is not identified in up to 10% of the patients. The aim of this study was to delineate the phenotype of pediatric and adult patients with a definite clinical diagnosis of TSC and no mutation identified in TSC1 or TSC2.We collected molecular and clinical data of 240 patients with TSC, assessing over 50 variables. We compared the phenotype of the homogeneous group of individuals with No Mutation Identified (NMI) with that of TSC patients with a TSC1 and TSC2 pathogenic variant.9.17% of individuals were classified as NMI. They were diagnosed at an older age (p?=?0.001), had more frequent normal cognition (p <?0.001) and less frequent epilepsy (p =?0.010), subependymal nodules (p?=?0.022) and giant cell astrocytomas (p?=?0.008) than patients with TSC2 pathogenic variants. NMI individuals showed more frequent bilateral and larger renal angiomyolipomas (p?=?0.001; p?=?0.003) and pulmonary involvement (trend) than patients with TSC1 pathogenic variants. Only one NMI individual had intellectual disability. None presented with a subependymal giant cell astrocytoma. Other medical problems not typical of TSC were found in 42.86%, without a recurrent pattern of abnormalities. Other TSC-associated neuropsychiatric disorders and drug-resistance in epilepsy were equally frequent in the three groups.This study provides a systematic clinical characterization of patients with TSC and facilitates the delineation of a distinctive phenotype indicative of NMI patients, with important implications for surveillance.  相似文献   

10.
Schistosomiasis is a worldwide parasitic disease. Currently, chemotherapy is the main effective method to treat schistosomiasis; however, it does not prevent reinfection. No effective vaccine is currently available to prevent schistosomiasis. Sj-F1 (GenBank accession number AY261995) is a novel gene that was discovered through screening adult Schistosoma japonicum worm cDNA library with female S. japonicum antigen-immunized sera. Streptococcus gordonii, a normal inhabitant of the human oral cavity, has been a prime candidate in recent investigations toward developing a live oral vaccine vector. One of the approaches for the surface expression of heterologous antigens in S. gordonii is to surface-localize them with the M6 protein from Streptococcus pyogenes. Here, we develop a recombinant S. gordonii strain that expresses the M6-Sj-F1 fusion protein on the bacterial surface. Intranasal immunization in mice with such M6-Sj-F1-expressing S. gordonii bacteria induced strong serum IgG, serum IgA, and saliva IgA against Sj-F1. The results of protective immunity against a challenge with cercariae of S. japonicum showed statistically significant protection following this treatment, with a worm reduction rate of 21.45 % and an egg reduction rate of 34.77 %. Our data indicate that the described M6-Sj-F1-expressing S. gordonii is highly immunogenic and can partially protect mice from challenge infection with S. japonicum. Intranasal immunization with recombinant S. gordonii may be an alternative to developing a novel S. japonicum vaccine in a safe, effective, and feasible way.  相似文献   

11.
12.
Helicobacter hepaticus is a bacterial pathogen that causes chronic active hepatitis and inflammatory bowel disease in mice. The purpose of this study was to develop a recombinant antigen-based enzyme-linked immunosorbent assay (ELISA) to detect H. hepaticus-infected mice. A genomic library of H. hepaticus was constructed and was screened with sera from H. hepaticus-infected mice. A 459-bp open reading frame that coded for an 18-kDa immunoreactive protein, MAP18, was identified. The gene had high identity with genes coding for outer membrane proteins of other bacteria, and the predicted amino acid sequence of MAP18 had a putative membrane-trafficking signal sequence and a putative signal peptidase II cleavage site. The recombinant protein was expressed in Escherichia coli as a glutathione S-transferase (GST) fusion protein, GST-MAP18, and purified by affinity chromatography. The 44-kDa fusion protein was detected on Western blots probed with sera from H. hepaticus-infected mice but was not detected on blots probed with sera from mice infected with Helicobacter muridarum or Helicobacter bilis or with sera from mice free of Helicobacter infection. The GST-MAP18 fusion protein was used as an antigen in an ELISA to detect anti-H. hepaticus antibodies in sera from infected mice. This ELISA was compared to an H. hepaticus-specific ELISA that uses a detergent extract of H. hepaticus as the antigen. Sera from mice naturally and experimentally infected with H. hepaticus, H. bilis, or H. muridarum and sera from mice free of Helicobacter infection were evaluated. Both ELISAs performed with a high specificity (98%); however, the detergent extract-based ELISA performed with a higher sensitivity (89%) than the recombinant protein-based ELISA (sensitivity, 66%). These data indicate that H. hepaticus carries a gene that encodes an immunogenic 18-kDa membrane-associated protein; however, antibodies to this protein are not detected in all infected mice.  相似文献   

13.
Metastatic melanoma is characterized by a poor response to chemotherapy. Furthermore, there is a lack of established predictive and prognostic markers. In this single institution study, we correlated mutation status and expression levels of BRAF and NRAS to dacarbazine (DTIC) treatment response as well as progression-free and overall survival in a cohort of 85 patients diagnosed with advanced melanoma. Neither BRAF nor NRAS mutation status correlated to treatment response. However, patients with tumors harboring NRAS mutations had a shorter overall survival (p < 0.001) compared to patients with tumors wild-type for NRAS. Patients having a clinical benefit (objective response or stable disease at 3 months) on DTIC therapy had lower BRAF and NRAS expression levels compared to patients progressing on therapy (p = 0.037 and 0.003, respectively). For BRAF expression, this association was stronger among patients with tumors wild-type for BRAF (p = 0.005). Further, low BRAF as well as NRAS expression levels were associated with a longer progression-free survival in the total population (p = 0.004 and <0.001, respectively). Contrasting low NRAS expression levels, which were associated with improved overall survival in the total population (p = 0.01), low BRAF levels were associated with improved overall survival only among patients with tumors wild-type for BRAF (p = 0.013). These findings indicate that BRAF and NRAS expression levels may influence responses to DTIC as well as prognosis in patients with advanced melanoma.  相似文献   

14.
Studies were undertaken to manufacture a multivalent Shigella inactivated whole-cell vaccine that is safe, effective, and inexpensive. By using several formalin concentrations, temperatures, and incubation periods, an optimized set of inactivation conditions was established for Shigella flexneri 2a, S. sonnei, and S. flexneri 3a to produce inactivated whole cells expressing a full repertoire of Ipa proteins and lipopolysaccharide (LPS). The inactivation conditions selected were treatment with 0.2% formalin (S. flexneri 2a and 3a) or 0.6% formalin (S. sonnei) for 48 h at 25°C. Vaccine formulations prepared under different inactivation conditions, in different doses (10E5, 10E7, and 10E9 cells), and with or without the inclusion of double-mutant heat-labile toxin (dmLT) were evaluated in mice. Two intranasal immunizations with ≥10E7 inactivated whole cells resulted in high levels of anti-Invaplex and moderate levels of LPS-specific IgG and IgA in serum and in lung and intestinal wash samples. Addition of dmLT to the vaccine formulations did not significantly enhance humoral immunogenicity. Minimal humoral responses for IpaB, IpaC, or IpaD were detected after immunization with inactivated whole Shigella cells regardless of the vaccine inactivation conditions. In guinea pigs, monovalent formulations of S. flexneri 2a of 3a or S. sonnei consisting of 10E8, 10E9, or 10E10 cells were protective in a keratoconjunctivitis assay. A trivalent formulation provided protection against all three serotypes (S. flexneri 2a, P = 0.018; S. flexneri 3a, P = 0.04; S. sonnei, P < 0.0001). The inactivated Shigella whole-cell vaccine approach incorporates an uncomplicated manufacturing process that is compatible with multivalency and the future development of a broadly protective Shigella vaccine.  相似文献   

15.
Chronic cavitary pulmonary aspergillosis (CCPA) is a progressive lung condition with a 10–30% annual mortality. Although overtly immunocompetent, some immunogenetic defect in patients is likely. To investigate a possible immunogenetic defect in CCPA, we analysed biologically plausible candidate genes in 112 CCPA patients and 279 healthy controls in a genetic association study of genes involved in the post-recognition immune response to Aspergillus fumigatus. We also compared gene expression in monocyte-derived macrophages from subjects with and without disease, both at baseline and during stimulation with A. fumigatus. Compared with macrophages from healthy subjects, CCPA macrophages showed unrestrained rises in IL1A, IL1B, IL6, IRAK2 and TRAF6 throughout the experiment, and a lack of expression of TGFB1 at 9 h. Single nucleotide polymorphisms (SNPs) associated with CCPA were found in IL1B (n = 2), IL1RN and IL15 (n = 3). Uncontrolled expression of IL1 and IL6 and continuing high levels of these cytokines may result in continuing cellular influx and pro-inflammatory responses, inhibiting disease resolution and contributing to disease progression in CCPA. The association of SNPs in IL1B, IL1RN and IL15 with CCPA supports a role for the IL1 pathway, as well as implicating the IL15 gene, in susceptibility to CCPA.  相似文献   

16.
We have investigated the role of bone-morphogenetic protein (BMP) 2 and tumor necrosis factor α (TNF-α) in 33 patients with bladder cancer (BCa) with bone metastasis. Thirty nonmetastatic BCas were included as controls. Immunohistochemical staining with BMP-2 and TNF-α was performed. Expressions of the factors were quantified and studied statistically. As a result, a trend showing higher expression of BMP-2 and TNF-α was associated with advanced disease. Expressions of BMP-2 and TNF-α were significantly higher in BCa with bone metastases (P = .0002 and P = .0172, respectively). The expression of BMP-2 and TNF-α showed a direct correlation in metastatic and muscle-invasive cases (P = .0202 and P = .0004, respectively) but not in nonmetastatic or noninvasive BCa (P = .1834 and P = .9215, respectively). It is postulated that BMP-2 can be responsible for the mechanism involved in triggering bone metastasis in BCa. The correlation with TNF-α indicates that the interaction of the 2 factors may promote local invasion and distant metastasis, especially to bone.  相似文献   

17.
In vertebrates, the tumor necrosis factor (TNF)-receptor (TNFR) system participates in diverse physiological and pathological events, such as inflammation and protective immune responses to microbial infections. There are few reports about the role of the invertebrate TNF-TNFR system in immune responses. Here, we isolated and characterized the TNF superfamily (LvTNFSF) gene, TNFR superfamily (LvTNFRSF) gene and lipopolysaccharide-induced TNF-α factor (LvLITAF) gene from Litopenaeus vannamei. LvTNFSF consists of 472 amino acids with a conserved C-terminal TNF domain and has 89.8% identity with the Marsupenaeus japonicus TNF superfamily gene. LvTNFRSF consists of 296 amino acids with a conserved TNFR domain and has 18.0% identity with Chlamys farreri TNFR, 14.6% identity with Drosophila melanogaster Wengen and 14.6% identity with Homo sapiens TNFR1. LvLITAF consists of 124 amino acids with the LITAF domain and shows 62.6% identity with D. melanogaster LITAF and 32.3% identity with H. sapiens LITAF. The promoter region of LvTNFSF was cloned and used to construct a luciferase reporter. In Drosophila S2 cells, the promoter of LvTNFSF can be activated by LvLITAF, L. vannamei NF-κB family proteins (LvRelish and LvDorsal) and LvSTAT. Unlike its mammalian counterparts, LvTNFRSF could not activate the NF-κB pathway in Drosophila S2 cells. Using real-time quantitative PCR, we obtained expression profiles of LvTNFSF, LvTNFRSF and LvLITAF in the gill, intestine and hepatopancreas of L. vannamei after challenge with Gram-negative Vibrio alginolyticus, Gram-positive Staphylococcus aureus, the fungus Candida albicans and white spot syndrome virus (WSSV). Taken together, our results reveal that LvTNFSF, LvTNFRSF and LvLITAF may be involved in shrimp immune responses to pathogenic infections.  相似文献   

18.
Type 1 narcolepsy, an autoimmune disease affecting hypocretin (orexin) neurons, is strongly associated with HLA-DQB1*06:02. Among polymorphisms associated with the disease is single-nucleotide polymorphism rs2305795 (c.*638G>A) located within the P2RY11 gene. P2RY11 is in a region of synteny conserved in mammals and zebrafish containing PPAN, EIF3G and DNMT1 (DNA methyltransferase 1). As mutations in DNMT1 cause a rare dominant form of narcolepsy in association with deafness, cerebellar ataxia and dementia, we questioned whether the association with P2RY11 in sporadic narcolepsy could be secondary to linkage disequilibrium with DNMT1. Based on genome-wide association data from two cohorts of European and Chinese ancestry, we found that the narcolepsy association signal drops sharply between P2RY11/EIF3G and DNMT1, suggesting that the association with narcolepsy does not extend into the DNMT1 gene region. Interestingly, using transethnic mapping, we identified a novel single-nucleotide polymorphism rs3826784 (c.596–260A>G) in the EIF3G gene also associated with narcolepsy. The disease-associated allele increases EIF3G mRNA expression. EIF3G is located in the narcolepsy risk locus and EIF3G expression correlates with PPAN and P2RY11 expression. This suggests shared regulatory mechanisms that might be affected by the polymorphism and are of relevance to narcolepsy.  相似文献   

19.
To know if alkaline phosphatase (AP) from schistosomes other than Schistosoma mansoni can be used as diagnostic marker for schistosomiasis in alkaline phosphatase immunocapture assay (APIA), we comparatively tested n-butanol extracts of adult worm membranes from a Venezuelan (JL) strain of S. mansoni (Ven/AWBE/Sm); a Cameroonian (EDEN) strain of Schistosoma intercalatum (Cam/AWBE/Si) and a Yemeni strain of Schistosoma haematobium (Yem/AWBE/Sh). APIA was evaluated with sera of patients from Venezuela, Senegal, and Gabon infected with S. mansoni, from Gabon infected with S. intercalatum or S. haematobium, from Chine infected with Schistosoma japonicum and from Cambodian patients infected with Schistosoma mekongi. Results indicate that 92.5 % (37/40) of Venezuela sera, 75 % (15/20) of Senegal sera, 39.5 % (17/43) of S. haematobium sera, and 19.2 % (5/26) S. intercalatum sera were APIA-positive with the Ven/AWBE/Sm preparation. APIA with the Cam/AWBE/Si preparation showed that 53.8 % of S. intercalatum-positive sera had anti-AP antibodies, and 51.2 %?S. haematobium-positive sera cross-immunocapturing the S. intercalatum AP. APIA performed with Yem/AWBE/Sh showed that 55.8 %?S. haematobium sera were positive. Only two out of nine S. japonicum sera were APIA-positive with the Ven/AWBE/Sm and Cam/AWBE/Si, and no reaction was observed with Cambodian S. mekongi-positive sera. AP activity was shown to be present in all the schistosome species/strains studied. The use of APIA as a tool to explore the APs antigenicity and the presence of Schistosoma sp. infections through the detection of anti-Schistosoma sp. AP antibodies in a host, allowed us to demonstrate the antigenicity of APs of S. mansoni, S. intercalatum, and S. haematobium.  相似文献   

20.
The indigenous microbial community of the gastrointestinal (GI) tract determines susceptibility to Clostridium difficile colonization and disease. Previous studies have demonstrated that antibiotic-treated mice challenged with C. difficile either developed rapidly lethal C. difficile infection or were stably colonized with mild disease. The GI microbial community of animals with mild disease was dominated by members of the bacterial family Lachnospiraceae, while the gut community in moribund animals had a predominance of Escherichia coli. We investigated the roles of murine Lachnospiraceae and E. coli strains in colonization resistance against C. difficile in germfree mice. Murine Lachnospiraceae and E. coli isolates were cultured from wild-type mice. The ability of each of these isolates to interfere with C. difficile colonization was tested by precolonizing germfree mice with these bacteria 4 days prior to experimental C. difficile challenge. Mice precolonized with a murine Lachnospiraceae isolate, but not those colonized with E. coli, had significantly decreased C. difficile colonization, lower intestinal cytotoxin levels and exhibited less severe clinical signs and colonic histopathology. Infection of germfree mice or mice precolonized with E. coli with C. difficile strain VPI 10463 was uniformly fatal by 48 h, but only 20% mortality was seen at 2 days in mice precolonized with the Lachnospiraceae isolate prior to challenge with VPI 10463. These findings confirm that a single component of the GI microbiota, a murine Lachnospiraceae isolate, could partially restore colonization resistance against C. difficile. Further study of the members within the Lachnospiraceae family could lead to a better understanding of mechanisms of colonization resistance against C. difficile and novel therapeutic approaches for the treatment and prevention of C. difficile infection.  相似文献   

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