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1.
Heliana B. Oliveira Gleyce A. Machado Maria do Rosário F. Gon?alves-Pires Leandro P. Moura Julia M. Costa-Cruz 《Parasitology research》2009,105(1):169-174
The aim of the present research was to test the application of Taenia saginata metacestodes as an alternative antigen for use in enzyme-linked immunosorbent assay (ELISA) and Western Blotting (WB) tests
compared with the use of metacestodes antigen of Taenia solium in cerebrospinal fluid (CSF) samples. The samples were obtained from 35 patients with definitive neurocysticercosis (NCC)—group
1—and 44 patients with other neurological disorders (control)—group 2. The sensitivity and specificity of ELISA, using antigen
obtained from T. solium, applied to the patients of group 1 yielded results of 100%. When the tests were conducted using T. saginata metacestodes, results were 100% and 93.2%, respectively. The 47–52-, 64–68-, and 70-kDa antigens showed high frequencies
in CSF samples from patients with NCC when WB was conducted with both antigens. The results indicate that T. saginata metacestodes can be used as an alternative antigen for the diagnosis of human NCC in CSF samples. 相似文献
2.
Italo M. Cesari Diana E. Ballen L. Mendoza Alain Ferrer Jean-Pierre Pointier Maryvonne Kombila Dominique Richard-Lenoble Andre Théron 《Parasitology research》2010,106(5):1225-1231
Antigens present in aqueous n-butanolic extracts (BE) of Schistosoma mansoni (Venezuelan JL strain), Schistosoma intercalatum (Cameroon EDEA strain), and Schistosoma haematobium (Yemen strain) adult worm membranes were compared in immunoblot against sera of patients infected with S. mansoni, S. intercalatum, S. haematobium, Schistosoma japonicum, or Schistosoma mekongi looking for similarities (common antigens) and differences (species-specific antigens). About 17 S. mansoni BE polypeptides (M
r ∼8 to >80 kDa) were commonly recognized by S. mansoni-infected patient sera from Venezuela, Senegal, and Ethiopia. S. intercalatum-, S. haematobium-, or S. japonicum-infected sera were almost unreactive with S. mansoni BE. Nonetheless, S. mekongi-infected sera weakly cross-reacted with a ∼10–15-kDa subset of S. mansoni BE. About 72.7% of S. intercalatum-infected patient sera reacted with a ∼19–21-kDa complex in S. intercalatum BE and cross-reacted with a similar complex in S. haematobium BE. Conversely, all S. haematobium-infected patient sera reacted with a ∼19–21-kDa complex in S. haematobium BE and cross-reacted with the ∼19–21-kDa complex in S. intercalatum BE; S. mansoni- and S. japonicum-infected patient sera did not react with S. intercalatum or S. haematobium BE. Results showed the presence of a common membrane antigen between African schistosome species and species-specific antigens
in S. mansoni BE that could be useful to discriminate between species and/or to detect Schistosoma infections. 相似文献
3.
Acute and long-term humoral immunity following active immunization of rabbits with inacctivated spores of various Encephalitozoon species 总被引:1,自引:0,他引:1
Sobottka I Iglauer F Schüler T Schmetz C Visvesvara GS Albrecht H Schwartz DA Pieniazek NJ Bartscht K Laufs R Schottelius J 《Parasitology research》2001,87(1):1-6
Microsporidia of the genus Encephalitozoon are increasingly being reported as a cause of severe, often disseminated infections, mainly in patients with acquired immunodeficiency
syndrome (AIDS). Immunological identification of each of the three recognized species (E. cuniculi, E. hellem, and E. intestinalis) requires the availability of specific immune sera. All sera available thus far have been generated by direct inoculation
of rabbits with virulent microsporidian spores. This study demonstrates for the first time that subcutaneous immunization
with inactivated spores of E. cuniculi, E. hellem, or E. intestinalis is capable of generating highly active rabbit hyperimmune sera to the homologous antigens, with maximal titers being 1:5,120,
1:1,280, and 1:2,560, respectively, as determined by the indirect immunofluorescence technique (IIF). Broad cross-reactivity
of the rabbit antisera with all heterologous Encephalitozoon antigens was determined by IIF and immunogold electron microscopy; however, only the E. hellem immune serum strongly cross-reacted with spores of Enterocytozoon bieneusi. During the 35-month follow-up period the antibody titers to the homologous antigens declined to 1:640, 1:160, and 1:320,
respectively. The observed decay curves for antibody titers against E. cuniculi, E. hellem, and E. intestinalis were fitted using mathematical modeling, resulting in a predicted duration for specific immune responses of about 7 years
on average. Knowledge of the magnitude and duration of specific immune responses is a prerequisite for further evaluation
of the concept of using inactivated microsporidian spores in the quest for vaccines against microsporidian infections.
Received: 10 April 2000 / Accepted: 18 July 2000 相似文献
4.
An immunoprecipitation technique using biotin-labeled proteins of Taenia solium was developed to identify antigens recognized by immunoglobulins from patients with neurocysticercosis. Six major polypeptides
of 100, 70, 50, 42, 35, and 24 kDa were recognized by cerebrospinal fluid from most serologically positive patients. All polypeptides
except the 70- and 35-kDa antigens were retained on a lentil-lectin chromatography column and were recognized by lentil lectin
in an overlay assay. The 70- and 35-kDa antigens were not labeled with biotin hydrazide, indicating that saccharide residues
are not present in these two polypeptides. Furthermore, the 70- and 35-kDa antigens were recognized by antibodies of more
than 86% of patients serologically positive for neurocysticercosis as opposed to none of the patients afflicted with other
neuropathologies of the central nervous system. This finding indicates that immunodiagnosis of neurocysticercosis can be carried
out with antigens different from those used in the standard enzyme-linked immunoelectrotransfer assay.
Received: 28 September 1998 / Accepted 15 December 1998 相似文献
5.
Lisiane V. Ev Antonio A. M. Maia Geraldo Pianetti E. Nascimento 《Parasitology research》1999,85(2):98-102
Human neurocysticercosis, due to infection of the central nervous system by cysticerci of Taenia solium, is a severe form of neurologic disease occurring in Central and South America. Specific proteins from scolex antigen from
cysticerci were purified by polyacrylamide gel electrophoresis and electroelution and recognized in Western blots by antibodies
present in sera from patients with neurocysticercosis. The proteins appeared as 13-, 17-, and 26-kDa bands on Coomassie blue-stained
gels and proved to be specific to cysticerci of T. solium. No cross-reactivity with sera from patients with taeniasis or hydatidosis was observed. Enzyme-linked immunosorbent assay
using the purified proteins of 13, 17, and 26 kDa demonstrated rates of 53%, 88%, and 100% specificity, respectively, at the
cutoff serum dilution of 1:32 for the specific immunodiagnosis of␣human neurocysticercosis.
Received: 10 May 1998 / Accepted: 21 July 1998 相似文献
6.
Laura Benitez Leslie J. S. Harrison R. Michael E. Parkhouse Luis M. Gonzalez Bruno Gottstein Teresa Garate 《Parasitology research》1998,84(5):426-431
A clone (R-Tso18) was isolated from a Taenia saginata oncosphere cDNA library by screening with sera from rabbits immunised with oncosphere extract. It contained a full-length
cDNA sequence of 1893 bp with an open reading frame of 1680 bp, corresponding to 559 amino acids with a deduced molecular
mass of 65.173 kDa and an isoelectric point of 6.08. The R-Tso18 protein showed 80–84% nucleotide identity with the major
protoscolex surface antigens of Echinococcus multilocularis (EM10) and E. granulosus (EG10). Preliminary immunogenicity studies employing the radio-labeled R-Tso18 protein in immune co-precipitation assays
indicated sero-positivity for T. saginata-infected calf sera (6/13), T. solium cysticercosis human (7/22) and pig (2/2) sera and E. multilocularis (6/10)- and E. granulosus (1/12)-infected human sera, whereas other helminth-infection sera were negative. As immuno-precipitation is a relatively
insensitive assay, it was concluded that further studies on the diagnostic potential of the purified recombinant R-Tso18 antigen,
or its peptides, are merited.
Received: 9 July 1997 / Accepted: 3 November 1997 相似文献
7.
Summary. To investigate the antigenic nature of cylindrical inclusion proteins (CIPs) of the potyviruses Turnip mosaic virus (TuMV) and Zucchini yellow mosaic virus (ZYMV), monoclonal antibodies (MAbs) against the two CIPs were produced and epitopes on the CIPs were localized using Escherichia coli-expressed CIP fragments in Western blot analysis. All 23 MAbs against ZYMV CIP reacted only with ZYMV CIP. In contrast out
of the 18 MAbs produced against TuMV CIP, 14 MAbs were TuMV CIP-specific while the remaining four MAbs cross-reacted with
both CIPs. The four cross-reactive MAbs recognized two distinct epitopes in the N-terminal half of TuMV CIP corresponding
to amino acid residues 103–119 and 224–237. Thirteen out of 14 TuMV CIP-specific MAbs recognized two distinct epitopes within
residues 1–102 and 120–214, while the other one recognized an epitope within residues 301–644. On the other hand, 21 out of
23 ZYMV CIP-specific MAbs recognized epitopes within residues 1–118, while the remaining two recognized epitopes within residues
301–522. These results suggest that cross-reactive and major virus-specific epitopes are located at the N-terminal half of
the respective CIPs.
Received August 10, 1999 Accepted March 2, 2000 相似文献
8.
Antigenic cross-reactivity between Treponema pallidum and other pathogenic members of the family Spirochaetaceae. 总被引:8,自引:6,他引:8 下载免费PDF全文
The antigenic cross-reactivity between Treponema pallidum and several pathogenic members of the family Spirochaetaceae was examined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and Western blotting techniques. Blots of T. pallidum antigens were incubated with antiserum from rabbits infected or immunized with T. pallidum, Treponema paraluiscuniculi, Treponema hyodysenteriae (strains B204 and T22), Borrelia hermsii serotype 7, or Leptopsira interrogans serogroup Canicola. T. pallidum contained 22 antigenic molecules ranging from 85,000 to 12,000 daltons which were recognized by serum from rabbits infected with T. pallidum. Serum from rabbits infected with T. paraluiscuniculi cross-reacted with 21 of these molecules and faintly reacted with a band at 15,000 daltons which was not recognized by anti-T. pallidum serum. Antisera directed against strains B204 and T22 of T. hyodysenteriae cross-reacted with 11 and 10 antigens of T. pallidum, respectively. B. hermsii and L. interrogans serogroup Canicola antisera detected 11 and 10 treponemal antigens, respectively. Many of the T. pallidum antigens detected by antisera against T. hyodysenteriae, B. hermsii, or L. interrogans serogroup Canicola have been previously identified as containing moieties also found on the nonpathogenic Treponema phagedenis, biotype Reiter, and may therefore represent group antigens common to members of the family Spirochaetaceae. 相似文献
9.
Larval and adult stages of Taenia solium and Taenia crassiceps WFU strain were analyzed by histochemical and biochemical methods to determine the existence of steroid pathways. The presence
of the key enzyme 3β-hydroxisteroid-dehydrogenase (3β-HSD) was examined in frozen sections of cysticerci obtained from mice
and segments of tapeworms obtained from the intestine of hamsters. 3β-HSD activity was detected by nitroblue-tetrazolium products
after incubation with dehydroepiandrosterone, androstendiol, or pregnenolone. Tapeworm tissues exhibited 3β-HSD activity in
the subtegumentary areas of the neck and immature proglottids following incubation with androstendiol, as well as surrounding
the testes in mature proglottids. T. solium cysticerci exhibited 3β-HSD activity in the subtegumentary tissues. The synthesis of steroid hormones involving the activity
of 3β-HSD was studied in cysticerci or tapeworms incubated in the presence of tritiated steroid precursors. The culture media
were analyzed by thin layer chromatography and showed synthesis of androstendiol, testosterone, and 17β-estradiol by cysticerci,
androstendiol, and 17β-estradiol by tapeworms. The results strongly suggest the activity of 3β-HSD in taeniid parasites that
have at least a part of the enzymatic chain required for androgen and estrogen synthesis and that the enzymes are present
in the larval stage and from the early strobilar stages to the mature proglottids. 相似文献
10.
T. A. Danilova 《Bulletin of experimental biology and medicine》1994,117(6):646-648
Heterophilic antibodies reacting with antigens of interstitial connective tissue of bovine myocardium were found in the sera
of patients with rheumatic fever. These antibodies were referred to class IgG. Immunologic specificity of the reaction with
these antigens was confirmed in experiments with F(ab′)2 fragments from IgG isolated from the sera of rheumatic patients. Heterophilic antibodies were not adsorbed by various antigens
of group AStreptococcus, nor were they isolated in a column with immunosorbent prepared on the basis of nontype-specific streptococcal antigens.
The reaction of patients' sera was not inhibited by monoclonal antibodies to nontype-specific antigens cross-reacting with
antigens of myocardial interstitial connective tisSue.
Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, N
o
6, pp. 642–644, June, 1994
Presented by S. V. Prozorovskii, Member of the Russian Academy of Medical Sciences 相似文献
11.
H.-R. Xiong Q. Li W. Chen D.-Y. Liu J.-X. Ling J. Liu Y.-J. Liu Y. Zhang Z.-Q. Yang 《European journal of clinical microbiology & infectious diseases》2011,30(5):645-651
Hemorrhagic fever with renal syndrome (HFRS) is endemic in East Asia and Europe. This study was initiated to investigate the
reactivity of antibodies in sera of Chinese HFRS patients with the recombinant nucleocapsid proteins (rNPs) of Hantaan virus (HTNV), Dobrava-Belgrade virus (DOBV), and Puumala virus (PUUV), which are the prevalent hantavirus strains in Europe. Forty-eight pairs of acute and convalescent sera were collected
from HFRS patients in Hubei, China (1985-2002) and tested by indirect IgG, IgA, and IgM enzyme-linked immunosorbent assays
with six rNPs of European hantaviruses as coated antigens, respectively. The results showed that the sensitivity of rNPs against
IgG was HTNV-rNP > DOBV-rNP > PUUV-rNP, while the sensitivity against IgA was DOBV-rNP > HTNV-rNP > PUUV-rNP. Quantitative
analysis revealed both acute and convalescent sera from HFRS patients predominantly exhibit high levels of IgA. Although PUUV-rNPs
showed very weak reactivity to the three kinds of immunoglobulins in all samples, three pairs of sera unexpectedly cross-reacted
strongly to all three PUUV-rNP subtypes. We first observe that HFRS patients’ sera from Hubei Province show new prevalent
characteristics of cross-reacting with PUUV-rNPs and continued high level of IgA in convalescent phase, as well as in China. 相似文献
12.
Immunological properties of procollagens obtained from the culture medium of dermatosparactic cells. 下载免费PDF全文
Rabbit antisera were produced against purified calf dermatosparatic procollagen and against the purified procollagens obtained from the culture medium of calf dermatosparatic cells. These antisera and their derived gamma-globulins were characterized by immunoprecipitation, double immunodiffusion and immunoelectrophoresis. Antiserum directed against dermatosparatic procollagen cross-reacted with the two different forms of procollagen obtained from the culture medium of dermatosparatic calf cells. Antiserum directed against onw of these procollagens, namely (pro alpha1)2 pro alpha2, cross reacted with dermatosparatic procollagen and also cross-reacted with the other procollagen,(pro alpha1)3. Antiserum directed against procollagen (pro alpha1)3 cross-reacted with dermatosparatic procollagen and with the procollagen (pro alpha1)2 pro alpha2. None of the antisera reacted with authentic calf skin collagen, or with the collagen extracted from the cell layer of the dermatosparatic calf cells in culture. Reduction andalkylation of the procollagens abolished the antigen-antibody reactions, while prior digestion of the antigens with bacterial collagenase did not eliminate the immunological reaction. Antigenic determinants in the cell culture procollagens were found at the COOH-terminal non-collagen peptide as well as at the NH2-terminal non-collagen peptide. 相似文献
13.
Patients infected with Trichomonas vaginalis mount humoral and cellular immune responses that often do not protect against reinfection. The oxidative stressors produced
by leukocytes may trigger a heat-shock-like response in T. vaginalis trophozoites, helping the parasite to survive host immune defenses. The antigenicity of T. vaginalis heat-shock proteins (HSPs) was examined by immunoprecipitation of T. vaginalis heat-induced proteins with sera from infected patients and controls. When T. vaginalis was heat-shocked, HSPs of 169–167 and 140–137 kDa were specifically recognized by sera from infected male and female patients.
However, the majority of T. vaginalis HSPs were also immunoprecipitated by control sera; all sera recognized 72- to 71-kDa, 47- to 45-kDa, 38- to 37-kDa, 35-kDa,
and 31-kDa heat-induced proteins. At least 15 proteins from non-heat-shocked T. vaginalis were immunoprecipitated by sera from infected patients and controls, indicating that natural or cross-reacting antibodies
could participate in host responses to trichomoniasis. Molecules of 158, 135, 89, and 74–72 kDa were immunoprecipitated from
some non-heat-shocked parasites only by patients' sera. A 38-kDa T. vaginalis protein was immunoprecipitated only by sera from infected females and may be specific for infection in women.
Received: 26 August 1999 / Accepted: 15 September 1999 相似文献
14.
Use of Taenia crassiceps Cysticercus Antigen Preparations for Detection of Antibodies in Cerebrospinal Fluid Samples from Patients with Neurocysticercosis (Taenia solium) 下载免费PDF全文
Alessandra Xavier Pardini Regina Helena Peralta Adelaide Jos Vaz Luis dos Ramos Machado Jos Mauro Peralta 《Clinical and Vaccine Immunology : CVI》2002,9(1):190-193
Antigen extracts obtained from the vesicular fluid of Taenia crassiceps cysticerci and from fractions purified by affinity chromatography with the lectin concanavalin A and the glycoprotein antigen separated by electrophoresis were used for the detection of Taenia solium anticysticercus antibodies. The sensitivity and specificity obtained for all antigens were 100% in enzyme-linked immunosorbent assay with good reproducibility. Using immunoblotting of the three antigens, low-molecular-mass peptides (18 and 14 kDa) were characterized only in cerebrospinal fluid samples from patients with neurocysticercosis. The results confirm that antigen fractions purified from T. crassiceps cisticerci are important sources of specific peptides and proved to be efficient in detecting anti-T. solium antibodies. 相似文献
15.
Mohamad Nidal Khabaz John McClure Sheena McClure Robert William Stoddart 《Comparative clinical pathology》2011,20(1):5-14
The factors that affect the progression of prostatic carcinoma are poorly understood, but it is known that carbohydrate antigens
on the tumour cell surface play a role in the transforming and metastatic processes. The present report aimed to perform a
comparative, lectin-histochemical study of benign and carcinomatous prostates, using a battery of 15 lectins, in combination
with monoclonal antibodies against Lewis antigens, and a semi quantitative study, to investigate the changes in glycosylation
patterns that occur in prostatic carcinoma. Blocks from 27 necropsy cases of prostatic carcinoma were sectioned and stained
with H&E, 15 biotinylated lectins chosen to probe for a wide range of oligosaccharide sequences within several categories
of glycoprotein glycans, using a lectin-biotin avidin–peroxidase method, and monoclonal antibodies against Lewisa, sialyl Lewisa and sialyl Lewisx antigens. The glycophenotype of prostatic carcinoma differed from that of the noncancerous prostate in revealing more intense
staining with the following lectins (AAA, UEA-1, DBA, WFA, VVA, HPA, BSA-1B4, MPA, ECA, AHA and CTA), while the binding patterns of (GNA and NPA) were almost similar in both prostatic carcinoma and
the noncancerous prostate. Lewis antigens are found to be expressed in prostatic carcinomas but not in the noncancerous prostate.
The observations of this study suggest that the gylcophenotype of transformed prostatic cells was modified. It showed a moderate
increase in, and changing patterns of, fucosylation and galactosylation, increased branching of side chains and sharp rise
in 2 deoxy, 2 acetamido galactosylation and masking process by sialylation, especially by α2–3 and α2–6 linkages. O-glycans seems to play an important role in the glycosylation patterns found in prostate carcinoma cells. 相似文献
16.
The therapeutic effect of praziquantel (PZQ) involves synergy with the humoral immune response during helminth infections,
which is modulated by parasitic antigens. During experimental murine infections with the larval stage of cestoda Mesocestoides vogae (syn. M. corti), dynamic changes in the IgG and IgM antibody serum levels to both soluble somatic and secretory larval antigens were investigated
after administration of PZQ alone and after its co-administration with the immunomodulator (l→3)-β-d-glucan entrapped in liposomes (lip.glucan).
During the 2 weeks of follow-up after termination of therapy, specific IgG and IgM serum levels to the somatic antigens (enzyme-linked
immunosorbent assay test) significantly decreased, whereas concentrations of the antibodies to the secretory antigens moderately
increased, both in comparison with the control. Moreover, the number of immunogenic larval antigens (analysed by Western blot)
was higher after combined therapy in comparison with single drug administration, which correlated with the intensity of reduction
of the larval counts in the liver and peritoneal cavity of mice. Our data showed that administration of PZQ alone and in combination
with lip.glucan resulted in marked changes in the dynamics of IgG and IgM antibodies to the somatic larval antigens, which
were probably induced by the newly exposed antigens. In this respect, glucan can enhance chemotherapeutic activity of PZQ
against larval cestodes by means of stimulation of the macrophage/monocyte effector functions, which seemed to contribute
to the more intense larval damage.
An erratum to this article can be found at 相似文献
17.
Salah F Demerdash Z Shaker Z El Bassiouny A El Attar G Ismail S Badir N El Din AS Mansour M 《Parasitology research》2000,86(1):74-80
A monoclonal antibody (mAb), 2F/11F, raised against Schistosoma haematobium soluble egg antigen (SEA) was found to be nonreactive with S. mansoni SEA or other parasite antigens (Fasciola hepatica, Echinococcus granulosus). This IgG1 mAb recognized a repetitive epitope on S. haematobium SEA in the molecular-weight regions of 70, 42, and 35 kDa. It was employed as both an antigen-capture and a biotinylated
detection antibody in a sandwich enzyme-linked immunosorbent assay (ELISA) for the detection of circulating schistosome antigen
(CSA) and had a detection limit of <1 ng S. haematobium SEA/ml. CSA levels were measured in serum and urine samples from 116 S. haematobium-infected rural students before therapy and at 4, 8, and 12 weeks after praziquantel treatment. Serum and urine samples from
50 S. mansoni -infected patients, 15 patients harboring other parasites, and 30 noninfected individuals were also assessed. CSA was detected
in 90.5% of serum samples and 94% of urine samples from S. haematobium-infected patients. CSA was undetectable in serum from the 15 patients harboring other parasites and in 94% of serum samples
and 84% of urine samples from S. mansoni-infected patients. In the S. haematobium-infected group a positive correlation was detected between CSA levels in serum and urine samples and the egg load per 10 ml
urine. A significant reduction in CSA levels was detected in serum and urine samples after praziquantel therapy. CSA was undetectable
in 87% of serum samples and 81.5% of urine samples from schistosomiasis haematobium patients at 12 weeks post-treatment. These
data demonstrate that the use of mAb 2F/11F for detection of CSA provides a sensitive method for the immunodiagnosis and monitoring
of cure of schistosomiasis haematobium.
Received: 5 December 1998 / Accepted: 26 June 1999 相似文献
18.
Glutathione S-transferase activity has been shown to be associated with the microsomal fraction of Taenia solium. Electron microscopy and subcellular enzyme markers indicate the purity of the microsomal fraction that contains the glutathione
S-transferase activity. T. solium microsomes were solubilized under conditions used to solubilize integral microsomal proteins. This procedure proved necessary
to obtain enzymatic activity. To characterize this parasite enzyme activity, several substrates and inhibitors were used.
The optimum activity for microsomal glutathione S-transferase was found to be pH 6.6, with a specific enzyme activity of 0.9, 0.1, 0.067, 0.03, and 0.05 μmol min−1 mg−1 with the substrates 1-chloro-2,4-dinitrobenzene (CDNB), 1,2-dichloro-4-nitrobenzene, 4-hydroxynonenal, 2,4-hexadienal, and
trans-2-nonenal, respectively. No activity of glutathione peroxidase was observed. T. solium microsomes had an app
K
m (GSH) = 0.161 μM, app
K
m (CDNB) = 14.5 μM, and app
V
max of 0.15 and 27.9 μmol min−1 mg−1 for GSH and CDNB, respectively. T. solium microsomes were inhibited by several glutathione S-transferase enzyme inhibitors, and it was possible to establish a simple inhibition system as well as corresponding K
i
’s for each inhibitor. These results indicate that the T. solium microsomal glutathione S-transferase is different from the parasite cytoplasmic enzymes that catalyze similar reactions. 相似文献
19.
Superoxide dismutase (SOD), a cytosolic enzyme that is specific for scavenging superoxide radicals, is involved in protective
mechanism(s) in tissue injury following oxidative processes and phagocytosis. The presence of SOD activity in larval and adult
Trichostrongylus colubriformis, Haemonchus contortus and Ostertagia circumcincta was examined using a xanthine-xanthine oxidase assay and by polyacrylamide gel electrophoresis (PAGE) and non-denaturing
sodium dodecyl sulfate (SDS)-PAGE followed by specific enzyme staining. Total antioxidant status was determined using the
Randox Laboratories kit. The infective larval stages (L3) of the three species contained 8–10 times more activity than the
corresponding adults. SOD activity from adult parasites was sensitive to KCN and SDS and may therefore belong to a Cu/Zn and
Mn class of enzymes. SOD from the larvae was sensitive only to KCN, suggesting that it may belong to a Cu/Zn class of enzymes.
Insignificant interspecies variation was observed when SOD isozyme profiles of larvae were compared. PAGE showed at least
five bands of SOD activity with molecular weights of between 18 and 205 kDa. Examination of total antioxidant status showed
that non-enzymatic antioxidant potential was also present, but only in the infective larvae. The level of antioxidants in
the three genera of larvae studied was similar and amounted to about 0.33–1.07 μM/mg of protein.
Received: 27 January 1998 / Accepted: 26 February 1998 相似文献
20.
A retrospective study of the experiments performed during the past 15 years on infections of Galba truncatula with Fasciola hepatica was carried out to determine what susceptible populations of snails might be used for the commercial production of metacercariae,
and to examine this metacercarial production in relation to the characteristics of snail infections. Of the four groups of
snail populations studied, the ablest snails to sustain a complete larval development of F. hepatica originated from populations living on siliceous soils at 600 m and more in altitude. In contrast, snail populations living
along river banks on siliceous soils were inappropriate due to the poor characteristics of snail infections (high snail mortality,
low prevalence of snail infections, and low number of cercariae produced). Except for these last populations, 86–87% of cercaria-shedding
(CS) snails in the other populations shed less than 300 cercariae, even if a maximum of 1,772 cercariae were obtained from
a single snail. The date of the first cercarial shedding at 20°C began during week 7 or 8 PE for 80.1–83.5% of CS snails.
Most metacercariae (82.0–85.9% of the total production) were recorded during the first 10 days of the patent period. In these
conditions, the authors collected metacercarial production up to the beginning of week 10 PE (20°C) and did not use snails
that shed their cercariae during the following weeks due to too low numbers of parasites. This method allows to have a continuous
production of metacercariae over time by using successive groups of infected snails, each being separated from the other by
a fortnight’s time. 相似文献