首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 453 毫秒
1.
Lymphatic filariasis is a major public health problem in India with 412 million people living in bancroftian endemic areas and is a major cause of clinical morbidity. Twenty million people are reported to suffer from chronic disease manifestations such as lymphoedema, hydrocele or elephantiasis. At least twice the number have been shown to suffer from acute and occult filarial infections in an endemic area without diagnosis. Due to non-availability of suitable diagnostic test for confirming filaria aetiology other than parasitological examination, no significant study on filariasis in children has been reported earlier. Studies in our laboratory for more than a decade showed usefulness of microfilarial excretory-secretory antigen in confirming filarial aetiology in acute and occult infections in adults as well as in children. This study reports acute and atypical manifestations such as lymphadenopathy, asthmatic bronchitis, pulmonary eosinophilia, mono-arthritis, recurrent URI, pneumonia, nutritional anemia, pain in abdomen etc. in children living in filaria endemic area having no microfilaraemia but showing filaria aetiology by immunomonitoring for the presence of antibody or antigen and responding to optimal DEC therapy.  相似文献   

2.
In vitro released antigens by living parasites or bacteria underin vitro maintenance or short term culture showing specific humoral immune response have been explored in development of immunodiagnostics for infectious diseases such as filariasis and tuberculosis in our laboratory. ELISA usingB. malayi mf ES antigen has been explored for detecting IgG antibody by Indirect ELISA and antigen by Inhibition ELISA and in immunomonitoring of carriers as well as clinical filarial cases. A ten year follow up of mf carriers with DEC therapy showed disapperance of antigen and antibody followed by reappearance in few cases in an endemic area. None of the cases followed developed clinical symptoms suggesting the need for long term monitoring and treatment of microfilaraemic carriers. Further immunomonitoring was found to be useful in confirming filaria aetiology in the absence of microfilaremia and determining appropriate period of treatment of acute, early clinical and occult filarial infections for clinical relief and cure.Indirect Stick Penicillinase ELISA system using Mtb EST-6 antigen for detecting tuberculous IgG antibody and a Sandwich Penicillinase ELISA system using affinity purified antibody for detecting circulating antigen were explored in tuberculosis. A combination of both the assay systems with a sensitivity of 70% and specificity of 98% was found to be promising in the precise diagnosis of pulmonary tuberculosis. Further antigen detection was found to be useful in bone and joint tuberculosis.  相似文献   

3.
A comparative analysis was made on the utility of SEVAFILACHEK-stick based immunoassays and commercially available ICT-filariasis test to detect active infection in different groups of bancroftian filariasis. The SEVAFILACHEK immunoassays were found to be useful to detect filarial infection in microfilaraemia and in a significant number of clinical filarial cases with acute, chronic and occult clinical manifestations. In the clinical cases, microfilariae are not usually detected in peripheral circulation. Employing SEVAFILACHEK assays 6 and 5 of the 7 samples of patients with chronic filarial disease, and 6 and 5 of 6 microfilaraemic cases gave positivity for filarial IgG antibodies and antigen respectively. Four of the 6 occult filarial samples were positive for antibodies and antigen. Filarial antigen was detected by ICT-filariasis test in blood samples of all the 6 microfilariaemic cases, 1 chronic filarial and 2 occult filarial samples. The main advantage of ICT assay is its rapid format and convenience for field use.  相似文献   

4.
Sera samples of 7 microscopic haematuria cases collected before and after treatment with Diethylcarbamazine citrate, (DEC), 9 microfilaraemic cases and 19 endemic normal individuals were analysed for filarial antigen and IgG antibody levels. Filarial antigen was detected in 5 of the 7 microscopic haematuria cases, of which 3 turned negative for antigen after treatment with DEC. While none of the 7 haematuria cases were positive for filarial IgG antibodies, before the DEC treatment, all of them turned positive after DEC treatment. The sensitivity and specificity values(to detect mf +ve cases) were 89% and 90% respectively for the detection of filarial antigen and 78% and 95% respectively for the detection of filarial IgG antibodies.  相似文献   

5.
The study was conducted in filarial endemic area for various clinical presentations and diagnosis of occult filariasis. A total of 157 cases of various clinical presentations namely tropical pulmonary eosinophilia, monoarthritis, polyarthritis, glomerulonephropathy, tenosynovitis, inguinal lymphadenopathy, generalised lymphadenopathy, retroperitonial lymphadenopathy, endomyocardial fibrosis and acute conjunctivitis were screened for filarial antigen and antibody by enzyme linked immunosorbent assay (ELISA). Out of 157 cases, 107 cases were positive for antigen or antibody, suggesting the role of filarial infection in these clinical presentations. All the 107 cases were treated with diethylcarbamazine citrate (DEC) and some of the patients who were followed showed relief in signs and symptoms. Hence assay of filarial antigen and/or antibody may be useful for diagnosing occult filarial syndromes for better management and further appropriate treatment.  相似文献   

6.
Brugia malayi microfilarial excretory-secretory (mf ES) antigens obtained byin vitro maintenance of mf are important tools in the immunodiagnosis of bancroftian filariasis. To increase the yield of mf ES products, the effect of nutritional supplements on the culture medium (RPMI 1640) and the maintenance temperature were studied. Supplementation of RPMI 1640 medium with organic acids and sugars of Grace's insect culture medium forin vitro maintenance of 10 lakhs of mf in 40 ml medium increased the yield of mf ES antigen from 152 μg to 364 μg of mean protein, content and the mean antigen titre from 200 to 400. Supplementation with phenyl methyl sulphonyl fluoride (PMSF) and shift in the culture temperature resulted in a further increase in the yield of mf ES antigen to 502 μg of mean total protein with an antigen titre of 800. The modification resulted in a net increase of 3 fold in the protein content and 4 fold in the antigen titre of ES products. The above modifications in thein vitro maintenance of mf did not affect the diagnostic quality of mf ES antigen, which gave a sensitivity and specificity of 80% and 90% respectively in detection of filarial IgG antibodies inWuchereria bancrofti infected cases.  相似文献   

7.
Human lymphatic filariasis is a chronic helminth infection caused byWuchereria bancrofti andBrugia malayi. Wide spectrum of clinical manifestations are seen in different clinical groups of filariasis patients which comprises asymptomatic patients with circulating microfilaria (MF), individuals with chronic lymphatic obstruction (CP), Endemic normals (EN) who are asymptomatic and amicrofilaraemic or the relatively rare tropical pulmonary eosinophilia (TPE). The cellular immune response to this infection varies in different clinical groups of filarial patients. ranging from normal lymphocyte proliferative response in EN individuals to lymphocyte hyporesponsiveness in MF to total parasite antigen [Brugia malayi antigen (BMA)]. But in response to recombinant filarial antigen (pRJ51) the lymphocyte proliferation is restored in MF patients. Interestingly the lymphocytes from MFs responded normally to parasite antigen when EN serum was added in the culture whereas sera from MFs failed to revert the lymphocyte hyporesponsiveness. In order to study the molecular mechanisms responsible for parasite antigen specific lymphocyte hyporesponsiveness, we analysed both the Th1 and Th2 type cytokine gene expression profile in different clinical groups of filarasis patients. MF individuals expressed elevated Th2 type cytokines like IL-4, IL-5 and IL-10 and decreased levels of IL-2 and IFN-γ in response to parasite antigen. Chronic patients have elevated levels of both Th1 and Th2 type cytokines in response to parasite antigen. The EN individuals had a purely Th1 type pattern with absence of IL-4 and IL-5 expression. These studies clearly demonstrate the role of Th2 cytokine like IL-10 in antigen specific hyporesponsiveness seen in MF patients. Any methods to arrest the progression of this disease should concentrate on the means to revert the Th2 type into Th1 type response in the MF patients either by Th1 type cytokine therapy or by using recombinant filarial antigen which stimulates the Th1 response. Further the recombinant filarial antigen which induces Th1 type cytokine response could be used for immunoprophylactic studies.  相似文献   

8.
A monoclonal antibody-based antigen detection system was used to detect the levels of circulating antigen in filarial patients before and after treatment with DEC and in normal individuals living in an area endemic forW. bancrofti infection in Chennai, India. The present study was to show the use of this assay as a means of efficient screening for filariásis in an endemic area where blood was absorbed onto the filter paper by finger prick during day time. The results of the antigen levels collected onto filter strips correlated with their corresponding plasma antigen levels (r=0.83). In microfilaraemics, DEC treatment did not alter the levels of circulating antigens upto a period of one month. We conclude that this monoclonal antibody based ELISA using filter strips may be used in daytime and can replace the existing routine night blood survey.  相似文献   

9.
Lymphatic filariasis caused mainly by infection fromWuchereria bancrofti andBrugia malayi remains as the major cause of clinical morbidity in tropical and subtropical countries. Development of vaccine against filarial infection can act as additional measure to the existing therapeutic and vector control methods in the control of this disease. The main hurdles in the development of anti-filarial vaccine are the strict primate specificity ofWuchereria bancrofti, the paucity of parasite material, the diversity of clinical manifestations and their associated complex immune responses, lack of clear understanding on host-parasite interactions and the mechanisms involved in protective immunity. However in the past few years, the information generated in immuno-epidemiological studies, correlated with observations in experimental animals suggests that a filarial vaccine is feasible. Initially live irradiated infective larvae have been successfully used to induce high level of protective immunity in several animal models. Applying diverse strategies, variety of purified or recombinant filarial antigens have been explored for their ability to induce protection in different host-parasite systems. Some of these targeted filarial antigens induced high level of resistance in experimental animals against challenge infections. More focussed studies on thorough characterization of parasitological and immunological changes associated with resistance induced by such candidate protective antigens and on delivery mechanisms and safety aspects will be crucial in their selection for possible use in humans.  相似文献   

10.
Lymphatic filariasis caused mainly by infection fromW. bancrofti andB. malayi remains a major cause of clinical morbidity in tropical and subtropical countries. Analysis ofB. malayi mf, infective larval and adult worm lysates for the activity of enzymes led to the demonstration of activities of three key enzymes of carbohydrate metabolism viz., Malate dehydrogenase (MDH), Malic enzyme (ME) and Glucose-6-phosphate dehydrogenase (G6PDH) in all the three stages of the parasite. The specific activity of all the three dehydrogenases was significantly high in mf lysate compared to their activity in lysates of the other two stages (P<0.001). Analysis by native polyacrylamide gel to their activity inlysates of the other two stages (P<0.001). Analysis by native polyacrylamide gel electrophoresis (PAGE) using 7.5% non-gradient gel showed the presence of two isoforms of each of the three enzymes (MDH, ME & G6PDH) in mf lysate, while only one form of each enzyme was present in L3 larval and adult worm lysates. Further proteolytic enzyme activity was demonstrated both in microfilarial and infective larval lysates ofB. malayi. While both mf and L3 larval lysates showed optimal protease activity at alkaline pH of 9.0, the mf lysate showed increased activity also at pH 3.0. The infective larval lysate was markedly inhibited by Tosylamide-L-Phenylalanine chloromethyl ketone (TPCK), a thiol protease inhibitor, while the protease activity in mf lysate was significantly inhibited by both TPCK and a serine protease inhibitor Phenyl Methyl Sulphonyl Flouride (PMSF). In sodium do-decyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE), using gelatin copolymerized gel, the microfilarial lysate showed 3 protease molecules of 40 kDa, 180 kDa and 200 kDa and the L3 larval lysate had 6 protease molecules of 18, 25, 37, 49, 70 and 200 kDa size.  相似文献   

11.
Lymphatic filariasis caused byWuchereria bancrofti is a major health problem next only to malaria. A study had been conducted to estimate the prevalence of microfilaraemia in a rural endemic community near Raipur. The incidence of microfilaramia in the community was found to be about 14% when studied by night finger prick method. The incidence appears to be more in males as compared to females. The infection rate in vector population i.e.,Culex quinquefasciatus was recorded at a rate of 10%. No relationship could be drawn between the rates of vector and human filarial infections or between the density of vector population and the rate of vector/human infection(s). Prior health education is essential before taking up control and preventive measures in given endemic zone.  相似文献   

12.
Analysis of tubercular antibody, circulating free and immune complexed antigen (CIC-Ag) was done in confimed pulmonary tuberculosis sera by ELISA, using ES-31 antigen and affinity purified anti ES-31 antibody. Twenty three of 25 (92%) tuberculosis sera were positive for IgG antibody to ES-31 antigen. Using anti ES-31 antibody, free tubercular antigen could be detected in 20 of 25 (80%) cases whereas circulating immune complexed antigen (CIC-Ag) in 18 of 25 (72%) cases by sandwich ELISA. Of the two sera showing absence of antibody, one showed presence of free and CIC-Ag whereas the other showed the presence of free antigen. Thus antigen assay may be used as an adjunct tool for confirmation of pulmonary tuberculosis.  相似文献   

13.
Trichloroacetic acid (TCA) solubilized and DEAE fractionatedMycobacterium tuberculosis H37Ra excretory-secretory (ES) antigen viz., Mtb EST DE1 and affinity purified goat antibodies to the TCA solubilized ES antigen (Mtb EST) were explored in detecting tubercular antibody and antigen respectively in sera of bone and joint tuberculosis by indirect and sandwich ELISA. Out of total 36 bone & joint tuberculosis cases, tubercular antibody was detected by indirect ELISA in 30 patients (sensitivity 83%), while circulating tubercular antigen was detected by sandwich ELISA in 27 patients (sensitivity 75%). Out of 34 non tubercular disease control cases, 10 patients showed positive reaction for antibody while only 4 patients showed positive reaction for antigen. In another group of 34 healthy subjects who were screened, 4 individuals showed positive reaction for tubercular antibody and 2 cases for antigen. This study shows that antigen detection assay using affinity purified anti Mtb EST antigen antibody is superior with overall specificity of 91% as compared to antibody detection assay with 75% specificity in bone & joint tuberculosis.  相似文献   

14.
A mycobacterial excretory-secretory protein fraction ESAS-7 purified by 50% ammonium sulphate precipitation followed by SDS-PAGE fractionation was evaluated by penicillinase enzyme linked immuno-sorbent assay (ELISA) for its sensitivity and specificity in the diagnosis of pulmonary tuberculosis. At a “cut off” serum dilution of 600, 38 (90%) of 42 sera from bacteriologically confirmed tuberculosis cases, 15 (100%) of 15 sera from bacteriogically negative but anti tubercular therapy (ATT) responded cases, 3 (7%) of 43 sera from normal healthy subjects and 4 (8%) of 48 sera from non tuberculous disease control cases gave positive reaction for tubercular antibody to ESAS-7 antigen fraction containing predominantly 33-kDa protein with a sensitivity of 90% in bacteriologically confirmed cases and specificity of 92%. Further, this diagnostic assay using the ESAS-7 antigen is more sensitive requiring as little as one nanogram antigen per test compared to use of 100 nanogram EST-6 antigen reported earlier. Thus use of ESAS-7 antigen for antibody detection has good diagnostic potential with improved specificity in pulmonary tuberculosis.  相似文献   

15.
A distinct British approach to disease in the tropics has been identified in the recent historiography of colonial medicine: Mansonian tropical medicine, named after Sir Patrick Manson (1844-1922), the founder of the London School of Tropical Medicine. This essay examines Manson's study of filariasis (infection with the filarial nematode worm) and argues that his conceptual tools and research framework were derived from contemporary natural history. It investigates Manson's training in natural history at the University of Aberdeen, where some of his teachers were closely associated with transcendental biology. The concepts of perfect adaptation and the harmony of nature were crucial to the formulation of his research problematic. This essay demonstrates that biogeographical concepts played an important part in Manson's research methodology. It also investigates how Manson's natural historical approach contributed to the making of so-called Mansonian tropical medicine.  相似文献   

16.
A rational approach for developing effective filaricides awaits greater knowledge on the biochemical pathways operating in filarial parasites. For example, metabolic pathways or key enzymes that are so pivotal to the parasite that their interruption or inhibition causes spontaneous death, could be exploited to develop effective chemotherapeutic agents. Similarly, developing a safe and nontoxic filaricidal will require precise understanding of whether or not the potential molecular target in the parasite is unique or at least different enough from the host system. Recently, we identified a novel transglutaminase enzyme (EC2.3.2.13; TGase) in filarial parasites that plays an important role during their normal growth and development. Based on these principles, TGase may serve as a new target for the development of effective chemotherapeutic agent and vaccine for controlling and preventing the infections caused by these parasites.  相似文献   

17.
Tuberculosis remains major health problem in India and developing countries Immunodiagnosis has important role in screening, diagnosis and management of tuberculosis. SEVA TB ES-31 antigen has shown potential in detecting tuberculous IgG antibody in earlier studies from our laboratory. In the present study we have analysedSEVA TB ES-31 antigen specific immunoglobulinsIgM, IgA and IgG in clinically and bacteriologically confirmed pulmonary tuberculosis cases to determine the usefulness of specific immunoglobulin class in the diagnosis of patients attending the hospital. Of the 30 cases of pulmonary tuberculosis 25 (83.3%) were positive for IgG, 19 (63.3%) for IgM and 16 (53.3%) for IgA. On combining IgG and IgM positivity, sensitivity was increased to 93.3%. While combining IgG and IgA positivity, sensitivity increased to 90%. However specificity was decreased to 66.6% and 70% for both of these combinations respectively. It could be envisaged from this study that IgG antibody detection against ES-31 antigen showed acceptable sensitivity (83.3%) and specificity (86.6%) compared to IgM or IgA alone or in combination. When immune responses were analysed according to degree of sputum positivity, IgG response was observed to be predominant in all grades, compared to IgM or IgA antibody. The addition of IgM or IgA as an adjunct test increases the sensitivity but at the cost of specificity. Hence the detection of IgG alone is more useful compared to IgM or IgA assay, in detecting tuberculosis disease cases coming to the hospital.  相似文献   

18.
Helminthic infections lead to the release of various molecules which play an important role in modulation of the host immune system. Such filarial proteins with immunomodulatory potential can be used for therapeutic purpose in inflammatory and immune mediated diseases. In the present study, we have explored the prophylactic effect of filarial SXP–RAL family protein of Wuchereria bancrofti i.e. rWbL2 protein in DSS induced inflammatory ulcerative colitis in a mouse model. Prior treatment of rWbL2, followed by induction of colitis, showed significantly reduced disease severity as indicated by the decreased disease manifestations and improved macroscopic and microscopic inflammation. This preventive effect was found to be associated with increased release of anti-inflammatory cytokine IL-10 and decreased release of proinflammatory cytokines IFN-γ, TNF-α, IL-6 and IL-17 by the splenocytes of treated mice. From this study, it can be envisaged that pretreatment with filarial protein, rWbL2, can prevent the establishment of ulcerative colitis in BALB/c mice. The underlying immunological mechanism may involve the up-regulation of Th2 immune response with down-regulation of Th1 response.  相似文献   

19.
Lactate dehydrogenase (LDH) and its isoenzyme profile, Nacety-β-d-glucosaminidase (NAG) and alanine aminopeptidase (AAP) enzyme activities were measured in 21 cases with well documented acute untreated urinary tract infections (UTI) and compared with a group of 68 normal healthy subjects matched for age and sex. Urinary NAG, AAP and LDH total activities were highly elevated (3–30 fold for NAG, 2–10 fold for AAP and 2–50 fold for LDH over upper limit of normal) in upper tract infections. In lower tract infections there was a marginal elevation in NAG and LDH while AAP activity was very high; though there was no overlap. Further, the isoenzyme profile of LDH showed predominance of LD-5 isoenzyme in all cases of pyelonephritis, while it was completely absent in all the cases of lower tract infections. We conclude that urinary NAG and LDH-5 isoenzyme would serve as specific non-invasive parameters for differential localization of urinary tract infections.  相似文献   

20.
Seven cases of suspected haemorrhage In pre-existing adenoma or cyst in the thyroid showed serum thyroglobulin (tg) levels phenomenonly elevated. The serum tg leveis reduced remarkably within one to three montha. During this period all patients were treated with thyroxin. It is concluded that serial serum thyroglobulin determinations may be useful in confirming the clinical suspicion of haemorrhage in the thyroid.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号