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1.
Zhonghua Liu Xing Bing Xue Za Zhi ; 41(7): 1103-1109, 2020 Jul 10.
Artigo em Chinês | MEDLINE | ID: mdl-32741179

RESUMO

Objective: To evaluate the protective efficacy and safety of Brucella 104M against aerosol challenge in BALB/c mice and characterize its immunological effects. Methods: Female mice of 6-8 weeks old were immunized with Brucella abortus strain 104M by intratracheal aerosol delivery or intranasal instillation or subcutaneous injection route. Six mice of each group were sacrificed at 4, 8, 16, 24 weeks after immunization. At each time point, the clinical manifestations of mice were investigated, the serum, spleen and lung samples of mice were collected, body weight, spleen weight, bacteria loads in spleens, the anti-Brucella antibodies titers in serum and the cytokines concentrations of IFN-γ, IL-18 in serum or lung homogenate of the mice were detected. Twenty two weeks after immunization, all the mice were challenged with Brucella A19 through intratracheal aerosol delivery. Results: Compared with the control group, neither abnormal clinical symptoms nor significant changes in body weight were found in 104M immunization groups, at each time point when immunized through either nose dropping route, subcutaneous injection or aerosol routes; and the spleen weight of immunization groups were lower than control group after challenge (P<0.05): *M1 (0.26±0.16)g

Assuntos
Anticorpos Antibacterianos/isolamento & purificação , Brucella abortus/imunologia , Brucelose/prevenção & controle , Imunização , Aerossóis , Animais , Feminino , Imunização/efeitos adversos , Camundongos , Camundongos Endogâmicos BALB C
2.
Zhonghua Yu Fang Yi Xue Za Zhi ; 54(2): 224-227, 2020 Feb 06.
Artigo em Chinês | MEDLINE | ID: mdl-32074715

RESUMO

The situation of prevention of non-neonatal tetanus in China is severe. Strengthening the active immunization with tetanus toxoid vaccine (TTCV) is the key to prevent the non-neonatal tetanus. Through the detection of tetanus antibody (TAB), the immune status of individual can be determined, so as to implement the active immunization of TTCV correctly. The research on TAB detection technology is stagnant in aboard, but still in a development process in China since there is a realistic demand for TAB detection. This review collects relatively limited data of TAB detection technology in China, and summarizes the techniques such as mice toxin neutralization test (MTNT), indirect hemagglutination assay (IHA), double agar gel immune diffusion test (Rubin method), enzyme-linked immunosorbent assay (ELISA) and colloidal gold (CG), in order to provide a comprehensive basis for domestic TAB detection. The TAB detection technology in China has not yet achieved international recognition due to the lack of comparative study of domestic and international institutions and reference reagents. The special domestic situation of tetanus prevention makes the research of TAB detection technology have a certain practical significance, and rapid detection reagents such as ELISA and CG method have a certain application value in China.


Assuntos
Anticorpos Antibacterianos/isolamento & purificação , Pesquisa Biomédica/tendências , Tétano/imunologia , Animais , China , Ensaio de Imunoadsorção Enzimática , Coloide de Ouro , Camundongos
3.
J Dermatol ; 46(10): 853-858, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31432529

RESUMO

In patients with lepromatous leprosy, Mycobacterium leprae is often observed inside the human microvascular endothelial cells (HMVEC) surrounding Schwann cells (SC) at the site of lesions in the peripheral nerves. Based on this observation, it is considered that the nasal mucous may be the invasion pathway for M. leprae and HMVEC serve as an important reservoir for the bacteria before they invade SC. In light of previous research which revealed that Mce1A protein mediates bacterial invasion into nasal epithelial cells and HMVEC, we conducted a study to determine whether the invasion of M. leprae into HMVEC can be suppressed by blocking the Mce1A protein. In this study, we analyzed bacterial invasive activity by adding recombinant Escherichia coli, which express the active region (InvX:72 a.a.) of Mce1A protein on their external membrane, into cultured HMVEC, using the adhesin involved in the diffuse adherence mechanism. The number of bacteria that invaded into the cells was then measured by a colony counting method. The active region of Mce1A was divided into four sections, and hyperimmune antisera was prepared for each section for analyzing the inhibitory effect against invasion. The invasive activity was suppressed by antibodies against InvX regions 1-24 a.a., 25-46 a.a. and 58-72 a.a. This suggests that the InvX regions 1-24 a.a., 25-46 a.a. and 58-72 a.a. of Mce1A protein play an important role in the invasion of M. leprae into HMVEC and that it may be possible to suppress entry of M. leprae in HMVEC with antibodies against these regions.


Assuntos
Anticorpos Antibacterianos/imunologia , Proteínas de Bactérias/imunologia , Células Endoteliais/microbiologia , Hanseníase/imunologia , Mycobacterium leprae/imunologia , Animais , Anticorpos Antibacterianos/isolamento & purificação , Proteínas de Bactérias/genética , Linhagem Celular , Contagem de Colônia Microbiana , Humanos , Soros Imunes/imunologia , Soros Imunes/isolamento & purificação , Hanseníase/microbiologia , Hanseníase/prevenção & controle , Mycobacterium leprae/patogenicidade , Coelhos , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia
4.
Prev Vet Med ; 169: 104698, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31311644

RESUMO

There is limited knowledge of the true prevalence and distribution of coxiellosis in dairy and beef cattle populations in Australia. For this to occur, apparent prevalence estimates need to be reliably adjusted, accounting for diagnostic sensitivity (DSe) and diagnostic specificity (DSp) of the test used. However, there are few tests available with known diagnostic specifications suitable to inform screening and surveillance activities in the Australian context. We initially modified and optimised a human indirect immunofluorescence assay (IFA) test for the detection of IgG antibodies against phase I and/or phase II Coxiella burnetii in bovine sera and determined an optimal screening dilution cut-off to be 1:160. Direct comparison of the modified IFA with the commercial IDEXX enzyme-linked immunosorbent assay (ELISA) kit (Q Fever Ab Test IDEXX Laboratories, United States of America) was performed by testing 458 serum samples from four distinct cattle populations across the east coast of Australia and New Zealand. Cross classified test results were then analysed using Bayesian latent class modelling, to validate the tests in the absence of a gold standard reference test. Results from this analysis indicate that the IFA, at a 1:160 serum dilution, has an estimated DSe of 73.6% (95% Credible Interval (CrI) 61.1, 85.9) and DSp of 98.2% (95% CrI 95.1, 99.7). The commercial IDEXX ELISA kit was found to have a higher DSe of 87.9% (95% CrI 73.9, 96.4) and similar DSp of 97.7% (95% CrI 93.2, 99.7). Evaluation of the diagnostic performance of the IFA and ELISA methods, specifically for use in cattle will enable more accurate interpretation of prevalence estimates of C. burnetii exposure to be reported for cattle in Australia and other countries.


Assuntos
Anticorpos Antibacterianos/isolamento & purificação , Doenças dos Bovinos/diagnóstico , Doenças dos Bovinos/microbiologia , Coxiella burnetii/isolamento & purificação , Técnica Indireta de Fluorescência para Anticorpo/veterinária , Febre Q/veterinária , Animais , Austrália , Teorema de Bayes , Bovinos , Doenças dos Bovinos/sangue , Coxiella burnetii/imunologia , Ensaio de Imunoadsorção Enzimática/veterinária , Técnica Indireta de Fluorescência para Anticorpo/normas , Imunoglobulina G/sangue , Nova Zelândia , Febre Q/sangue , Febre Q/diagnóstico , Sensibilidade e Especificidade
5.
Acta Trop ; 197: 105026, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31103700

RESUMO

Brucellosis is caused by the genus Brucella. Brucella is widely distributed in cattle, swine, sheep, goat and other mammals including human. Animal brucellosis causes severe economic losses and affects related international transportation and trade. Human brucellosis causes both acute and chronic symptoms of multi-organ dysfunction. Brucella type IV secretion system (T4SS) VirB5 was required for macrophages infection and essential for virulence in mice. VirB5 is located on the cell surface and serves as a specific adhesin targeting host cell receptors. The aim of this study was to isolate and characterize a specific human domain antibody against Brucella abortus (B. abortus) VirB5 from human single domain antibody (sdAb or VHH) phage display library. Following five rounds of screening, an sdAb named as BaV5VH4 showed the highest affinity by enzyme-linked immunosorbent assay (ELISA). Its interaction with B. abortus VirB5 was verified by binding assay, dot blot and molecular docking. These findings in this paper could greatly help elucidate the molecular mechanisms of Brucella infection, and accelerate the development of sdAbs-based vaccines and neutralizing therapeutics of brucellosis.


Assuntos
Anticorpos Antibacterianos/imunologia , Brucella abortus/imunologia , Brucelose/prevenção & controle , Sequência de Aminoácidos , Animais , Anticorpos Antibacterianos/genética , Anticorpos Antibacterianos/isolamento & purificação , Proteínas de Bactérias/genética , Proteínas de Bactérias/imunologia , Proteínas de Bactérias/isolamento & purificação , Bacteriófagos/imunologia , Sequência de Bases , Brucella abortus/genética , Brucella abortus/isolamento & purificação , Brucelose/economia , Bovinos , Ensaio de Imunoadsorção Enzimática , Cabras , Humanos , Immunoblotting , Camundongos , Simulação de Acoplamento Molecular , Filogenia , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Ovinos , Suínos , Virulência , Fatores de Virulência/metabolismo , Zoonoses/prevenção & controle
6.
BMC Res Notes ; 12(1): 228, 2019 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-30992057

RESUMO

OBJECTIVE: Intravenous immune globulin (IVIG), pooled from human blood, is a polyspecific antibody preparation that inhibits the super-antigenic proteins associated with streptococcal and staphylococcal toxic shock, and the Shiga toxin. In addition to this toxin-neutralising activity, IVIG contains other pathogen-reactive antibodies that may confer additional therapeutic benefits. We sought to determine if pathogen-reactive antibodies that promote opsonophagocytosis of different organisms can be sequentially affinity-purified from one IVIG preparation. RESULTS: Antibodies that recognise cell wall antigens of Streptococcus pyogenes, Staphylococcus aureus, and vancomycin-resistant enterococcus (VRE) were sequentially affinity-purified from a single preparation of commercial IVIG and opsonophagocytic activity was assessed using a flow cytometry assay of neutrophil uptake. Non-specific IgG-binding proteins were removed from the S. aureus preparations using an immobilised Fc fragment column, produced using IVIG cleaved with the Immunoglobulin G-degrading enzyme of S. pyogenes (IdeS). Affinity-purified anti-S. aureus and anti-VRE immunoglobulin promoted significantly higher levels of opsonophagocytic uptake by human neutrophils than IVIG when identical total antibody concentrations were compared, confirming activity previously shown for affinity-purified anti-S. pyogenes immunoglobulin. The opsonophagocytic activities of anti-S. pyogenes, anti-S. aureus, and anti-VRE antibodies that were sequentially purified from a single IVIG preparation were undiminished compared to antibodies purified from previously unused IVIG.


Assuntos
Anticorpos Antibacterianos/farmacologia , Imunoglobulinas Intravenosas/química , Neutrófilos/efeitos dos fármacos , Proteínas Opsonizantes/farmacologia , Fagocitose/efeitos dos fármacos , Anticorpos Antibacterianos/isolamento & purificação , Antígenos de Bactérias/química , Antígenos de Bactérias/imunologia , Parede Celular/química , Cromatografia de Afinidade/métodos , Humanos , Fragmentos Fc das Imunoglobulinas/química , Neutrófilos/citologia , Neutrófilos/imunologia , Proteínas Opsonizantes/isolamento & purificação , Cultura Primária de Células , Staphylococcus aureus/química , Staphylococcus aureus/imunologia , Staphylococcus aureus/patogenicidade , Streptococcus pyogenes/química , Streptococcus pyogenes/imunologia , Streptococcus pyogenes/patogenicidade , Enterococos Resistentes à Vancomicina/química , Enterococos Resistentes à Vancomicina/imunologia , Enterococos Resistentes à Vancomicina/patogenicidade
7.
PLoS One ; 14(4): e0214402, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31034492

RESUMO

Spirochaetes of the Borrelia burgdorferi sensu lato complex, which includes those that cause Lyme disease, have not been identified in Australia. Nevertheless, Australian patients exist, some of whom have not left the country, who have symptoms consistent with so-called "chronic Lyme disease". Blood specimens from these individuals may be tested in Australian laboratories and in specialist laboratories outside Australia and sometimes conflicting results are obtained. Such discrepancies cause the patients to question the results from the Australian laboratories and seek assistance from the Australian Government in clarifying why the discrepancies occur. The aim of this study was to determine the level of agreement in results between commonly used B. burgdorferi serology assays in specimens of known status, and between results reported by different laboratories when they use the same serology assay. Five immunoassays and five immunoblots used in Australia and elsewhere were examined for the detection of IgG antibodies to Borrelia burgdorferi sensu lato. Predominantly, archived specimens previously tested for Lyme disease were used for the study and included 639 contributed by seven clinical laboratories located either in Australia or in areas endemic for Lyme disease. Also included were 308 prospectively collected Australian blood donor specimens. All clinical specimens were tested in all 10 assays whereas blood donor specimens were tested in all immunoassays and a subset was tested on immunoblots. With the exception of one immunoblot, the results between the assays agreed with each other in a known positive specimen population ≥ 77% of the time and in a known negative population, 88% of the time or greater. The test results obtained during the study were different from the participating laboratory's less than 2% of the time when the same assay was used. These findings suggest that discordance in results between laboratories is more likely due to variation in algorithms or in the use of assays with different sensitivities or specificities rather than conflicting results being reported from the same assay in different laboratories. In the known negative population, specificities of the immunoassays ranged between 87.7% and 99.7%. In Australia's low prevalence population, this would translate to a positive predictive value of < 4%.


Assuntos
Borrelia burgdorferi/isolamento & purificação , Testes Imunológicos , Doença de Lyme/sangue , Doença de Lyme/imunologia , Anticorpos Antibacterianos/imunologia , Anticorpos Antibacterianos/isolamento & purificação , Austrália/epidemiologia , Doadores de Sangue , Borrelia burgdorferi/patogenicidade , Grupo Borrelia Burgdorferi/imunologia , Grupo Borrelia Burgdorferi/isolamento & purificação , Feminino , Humanos , Doença de Lyme/diagnóstico , Doença de Lyme/microbiologia , Masculino , Testes Sorológicos
8.
J Infect Chemother ; 25(10): 769-773, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31023569

RESUMO

BACKGROUND: Serum Helicobacter pylori (H. pylori) antibody kits (LZ and LIA) using the latex agglutination immunoassay method are commercially available, but few studies have been performed to determine their diagnostic accuracy or to compare their results with those of enzyme-linked immunosorbent assay (ELISA) kits (EP and EIA). METHODS: Sera were obtained from 213 hospital outpatients with dyspeptic symptoms. The serological results were compared with the result of the 13C-urea breath test (UBT) which seems to be reliable. RESULTS: Of the 213 subjects, 154 were diagnosed as positive for H. pylori infection according to the UBT. The sensitivities and specificities of these tests were 97.4% and 76.3%, 98.1% and 78.0%, 99.4% and 74.6%, and 98.1% and 71.2% for the EP, LZ, EIA and LIA tests, respectively. When the 13 subjects whose seropositive results of the four kits were completely opposite to the negative results of the UBT were excluded, the specificities of evaluated kits were all higher than 90%. The concordance rate between the EP and EIA tests was 98.1% (Spearman's rank correlation coefficient = 0.83) and that between the LZ and LIA tests was 97.1% (correlation coefficient = 0.91). The LZ gave higher antibody titer value than EP (p < 0.0001, Z = 9.82; Wilcoxon signed-rank test), and EIA gave higher value than LIA (p < 0.0001, Z = 6.43; Wilcoxon signed-rank test). CONCLUSIONS: The latex immunoassay method provided the same reliability to ELISA in terms of the diagnostic accuracy for current H. pylori infection, although we should take into account the titer value differences by each test method in practical use.


Assuntos
Anticorpos Antibacterianos/isolamento & purificação , Infecções por Helicobacter/diagnóstico , Helicobacter pylori/isolamento & purificação , Testes de Fixação do Látex/instrumentação , Ureia/análise , Adulto , Idoso , Idoso de 80 Anos ou mais , Testes Respiratórios/instrumentação , Isótopos de Carbono/análise , Comércio , Ensaio de Imunoadsorção Enzimática/economia , Ensaio de Imunoadsorção Enzimática/instrumentação , Ensaio de Imunoadsorção Enzimática/estatística & dados numéricos , Feminino , Infecções por Helicobacter/sangue , Infecções por Helicobacter/microbiologia , Helicobacter pylori/imunologia , Humanos , Testes de Fixação do Látex/economia , Testes de Fixação do Látex/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Ureia/química , Adulto Jovem
9.
PLoS One ; 14(3): e0212893, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30835745

RESUMO

The serological detection of antibodies to Treponema pallidum is essential to the diagnosis of syphilis. However, for the presence of cross-reaction, the specific antibody tests [e.g., enzyme-linked immunosorbent assay (ELISA)] always have false-positive results. In this study, we derived and validated the dissociation of urea in an attempt to alleviate the situation of false-positive antibodies to T. pallidum detected by ELISA. Six serum samples that were false-positive antibodies to T. pallidum detected by ELISA, and 16 control serum samples (8 sera positive for both specific IgG and IgM, and 8 IgG-positive and IgM-negative sera) were collected to select the appropriate dissociated concentration and time of urea. Our goal was to establish improved an ELISA method based on the original detection system of ELISA. The sensitivity of the improved ELISA was evaluated by 275 serum samples with class IgM-positive antibodies to T. pallidum. At 6 mol/L with 10 minutes dissociation of urea, 6 samples with false-positive antibodies to T. pallidum were converted to negative, and compared with true-positive antibodies to T. pallidum. The sensitivity of the improved ELISA was 100% by detecting the class IgM-positive antibodies to T. pallidum in sera of patients with syphilis. Considering the importance at the diagnosis of syphilis, antibodies to T. pallidum in serum samples should be retested by the improved ELISA method to avoid false-positive results.


Assuntos
Anticorpos Antibacterianos/isolamento & purificação , Sorodiagnóstico da Sífilis/métodos , Sífilis/diagnóstico , Treponema pallidum/isolamento & purificação , Ureia/química , Anticorpos Antibacterianos/sangue , Anticorpos Antibacterianos/imunologia , Antígenos de Bactérias/imunologia , Ensaio de Imunoadsorção Enzimática/métodos , Reações Falso-Positivas , Humanos , Imunoglobulina M/sangue , Imunoglobulina M/imunologia , Imunoglobulina M/isolamento & purificação , Sensibilidade e Especificidade , Sífilis/sangue , Sífilis/microbiologia , Treponema pallidum/imunologia
10.
Jpn J Infect Dis ; 72(3): 168-172, 2019 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-30700657

RESUMO

We evaluated the prevalence of Anaplasma infection in 332 dogs from Ibaraki, Japan, using serological and molecular methods. An immunofluorescence antibody assay against Anaplasma phagocytophilum indicated that 7 of the 328 serum samples tested (2.1%) were positive for A. phagocytophilum. Screening by polymerase chain reaction (PCR) analysis demonstrated that 8 of the 331 peripheral blood samples tested (2.4%) were positive for Anaplasmataceae. Phylogenetic analysis of the partial 16S rRNA sequence of the PCR amplicons revealed that 6 sequences were most similar to the 16S rRNA sequence of a Wolbachia sp., and the remaining 2 to A. bovis. Further analysis by A. phagocytophilum-specific nested PCR demonstrated that 1 dog infected with A. bovis was also positive for A. phagocytophilum. This is the first study to report the dual infection of a dog in Japan with A. bovis and A. phagocytophilum.


Assuntos
Anaplasma/genética , Anaplasmose/epidemiologia , Doenças do Cão/epidemiologia , Doenças do Cão/microbiologia , Anaplasma/isolamento & purificação , Anaplasma phagocytophilum/isolamento & purificação , Anaplasmose/sangue , Animais , Anticorpos Antibacterianos/isolamento & purificação , DNA Bacteriano/genética , Doenças do Cão/sangue , Cães , Feminino , Imunofluorescência/veterinária , Japão/epidemiologia , Masculino , Reação em Cadeia da Polimerase/veterinária , Prevalência
11.
Mol Immunol ; 106: 63-68, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30583222

RESUMO

Sepharose matrix without immobilized ligands binds antibodies from human blood serum or immunoglobulin preparations. The eluted antibodies bind bacterial polysaccharides having no structural similarity to agarose (Sepharose is a cross-linked polysaccharide agarose) with a high affinity. It is concluded that the identified antibodies are capable of recognizing spatial rather than linear epitopes of bacterial polysaccharides. This side activity of Sepharose matrix should be taken into account in isolating target antibodies and other proteins from human blood.


Assuntos
Anticorpos Antibacterianos/isolamento & purificação , Polissacarídeos Bacterianos/química , Anticorpos Antibacterianos/sangue , Anticorpos Antibacterianos/imunologia , Humanos , Polissacarídeos Bacterianos/imunologia , Sefarose/química
12.
J Infect Chemother ; 24(11): 887-891, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30197093

RESUMO

The accuracy of the test is critical for the syphilis serology diagnosis. This study aims to evaluate the values of the Elecsys syphilis assay, the Architect syphilis assay, and the Mindray syphilis assay, as syphilis screening tests for pregnant women and patients with syphilis or other diseases. A reverse algorithm was used for the syphilis serology diagnosis. Serum samples (n = 584) were tested with three automated screening assays. All reactive sera by one, two, or three screening assays were further analyzed with the tolulized red unheated serum test (TRUST). Inconsistent results were confirmed by the Treponema pallidum particle agglutination assay (TPPA). The final patient diagnosis was made according to the results of syphilis serology, clinical evidence, and past medical history. The sensitivity, specificity, accuracy, and kappa value of each assay were as follows: for the Elecsys syphilis assay, 100.0%, 98.5%, 98.6%, and 0.927, respectively; for the Architect syphilis assay: 100.0%, 94.5%, 95.0%, and 0.770; and for the Mindray syphilis assay: 100.0%, 97.0%, 97.3%, and 0.862. The McNemar test showed that there were significant differences in the performance between the Elecsys syphilis assay and the Architect syphilis assay (P < 0.001), and between the Mindray syphilis assay and the Architect syphilis assay (P = 0.001). Our study demonstrated that three automated Treponema pallidum antibody assays generally showed high sensitivities and specificities, and so, they are suitable for use in screening for syphilis. The performances of the Elecsys syphilis assay and the Mindray syphilis assay are superior to Architect syphilis assay.


Assuntos
Anticorpos Antibacterianos/isolamento & purificação , Complicações Infecciosas na Gravidez/diagnóstico , Sorodiagnóstico da Sífilis/métodos , Sífilis/diagnóstico , Treponema pallidum/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Anticorpos Antibacterianos/imunologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Gravidez , Complicações Infecciosas na Gravidez/sangue , Complicações Infecciosas na Gravidez/imunologia , Complicações Infecciosas na Gravidez/microbiologia , Estudos Prospectivos , Sensibilidade e Especificidade , Sífilis/sangue , Sífilis/imunologia , Sífilis/microbiologia , Treponema pallidum/isolamento & purificação , Adulto Jovem
13.
Afr Health Sci ; 18(1): 22-28, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29977253

RESUMO

Background: Brucellosis is a disease with significant public and economic implications but strategies for controlling this disease remain problematic. Objectives: This study sought to determine the sero-prevalence of brucellosis in prolonged fever patients and to identify modifiable risk factors for the infection in humans in post conflict Northern Uganda. Methods: The study employed a cross-sectional method among prolonged fever patients who had visited selected health facilities in the study districts in Northern Uganda. Sero-prevalence of brucellosis was calculated for i-ELISA IgG/IgM. A structured questionnaire was used to obtain data on possible risk factors for brucellosis. Associations between sero-prevalence and risk factors were measured using the Odds Ratio. Results: Brucellosis was confirmed in 18.7% of the 251 patients that tested positive for the disease, with the rapid Brucella Plate Agglutination Test, and ages 10-84 years (median age 47+0.86). Sex (p = 0.001; OR 3.79; 95% CI 1.75 - 8.24), rearing livestock (p < 0.005; OR 8.44; 95% CI 2.84-25.03) and consumption of unpasteurised milk (p = 0.023; OR 2.57; 95% CI 1.14-5.80) were factors associated with brucellosis. Conclusion: Control of brucellosis in animals, training and sensitisation of the community on brucellosis is needed to stimulate action on human brucellosis control.


Assuntos
Anticorpos Antibacterianos/sangue , Brucella/isolamento & purificação , Brucelose/epidemiologia , Febre/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Anticorpos Antibacterianos/isolamento & purificação , Brucelose/diagnóstico , Criança , Estudos Transversais , Ensaio de Imunoadsorção Enzimática , Feminino , Febre/complicações , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Estudos Soroepidemiológicos , Uganda/epidemiologia , Adulto Jovem , Zoonoses
14.
Epidemiol Infect ; 146(11): 1384-1388, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29970200

RESUMO

To investigate the impact of viral and bacterial co-infection in hospitalised children with Mycoplasma pneumoniae pneumonia (RMPP). Retrospective analysis of 396 children with RMPP in our hospital admitted between 1 January 2011 and 31 December 2016 was performed. Nasal aspirate samples were collected for pathogen detection and clinical data were collected. We analysed clinical characteristics, lung imaging characteristics and pathogenic species among these children. Of the 396 RMPP cases, 107 (27.02%) had co-infection with other pathogen, with Streptococcus pneumoniae, Haemophilus influenzae and Staphylococcus aureus being the most common bacteria of infection and human bocavirus (HBoV), human rhinovirus, respiratory syncytial virus being the most common viruses of infection. Children with co-infection were younger than that with single infection (P = 0.010). Children with both virus and bacteria co-infection had been the youngest (P = 0.040). Children with co-infection had a longer fever process, higher leukocyte count, higher C-reactive protein compared with single infection (P < 0.05). Children with co-infection had a higher percentage of pnemothorax and diffuse large area of inflammation in chest X-ray manifestation compared with children with single infection (P < 0.05). S. pneumonia and HBoV was the leading cause of co-infection in RMPP. Co-infections led to more disease severity in children with RMPP compared with single infections.


Assuntos
Infecções Bacterianas/complicações , Coinfecção , Pneumonia por Mycoplasma/complicações , Viroses/complicações , Distribuição por Idade , Anticorpos Antibacterianos/isolamento & purificação , Infecções Bacterianas/microbiologia , Criança , Pré-Escolar , Feminino , Haemophilus influenzae/isolamento & purificação , Bocavirus Humano/genética , Bocavirus Humano/isolamento & purificação , Humanos , Imunoglobulina M/isolamento & purificação , Lactente , Pacientes Internados , Masculino , Metapneumovirus/genética , Metapneumovirus/isolamento & purificação , Nasofaringe/virologia , RNA Ribossômico 16S/genética , Radiografia Torácica , Reação em Cadeia da Polimerase em Tempo Real/métodos , Estudos Retrospectivos , Rhinovirus/genética , Rhinovirus/isolamento & purificação , Estações do Ano , Staphylococcus aureus/isolamento & purificação , Streptococcus pneumoniae/isolamento & purificação , Viroses/virologia
15.
Eur J Clin Microbiol Infect Dis ; 37(9): 1673-1678, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29948363

RESUMO

The tick-borne bacterium Candidatus (Ca.) Neoehrlichia (N.) mikurensis is a cause of "fever of unknown origin" because this strict intracellular pathogen escapes detection by routine blood cultures. Case reports suggest that neoehrlichiosis patients may display serological reactivity to Anaplasma (A.) phagocytophilum. Since Anaplasma serology is part of the diagnostic work-up of undetermined fever in European tick-exposed patients, we wanted to investigate (1) the prevalence of A. phagocytophilum seropositivity among neoehrlichiosis patients, (2) the frequency of misdiagnosed neoehrlichiosis patients among A. phagocytophilum seropositive patients, and (3) the frequency of A. phagocytophilum and Ca. N. mikurensis co-infections. Neoehrlichiosis patients (n = 18) were analyzed for A. phagocytophilum IgM and IgG serum antibodies by indirect immunofluorescence assay. Serum samples from suspected anaplasmosis patients (n = 101) were analyzed for bacterial DNA contents by singleplex PCR specific for A. phagocytophilum and Ca. N. mikurensis, respectively. One fifth of the neoehrlichiosis patients (4/18) were seropositive for IgM and/or IgG to A. phagocytophilum at the time of diagnosis. Among the patients with suspected anaplasmosis, 2% (2/101) were positive for Ca. N. mikurensis by PCR whereas none (0/101) had detectable A. phagocytophilum DNA in the serum. To conclude, patients with suspected anaplasmosis may in fact have neoehrlichiosis. We found no evidence of A. phagocytophilum and Ca. N. mikurensis co-infections in humans with suspected anaplasmosis or confirmed neoehrlichiosis.


Assuntos
Anaplasma phagocytophilum/imunologia , Bactérias/imunologia , Ehrlichiose/diagnóstico , Ehrlichiose/imunologia , Febre/imunologia , Adulto , Idoso , Anaplasma phagocytophilum/genética , Animais , Anticorpos Antibacterianos/sangue , Anticorpos Antibacterianos/isolamento & purificação , Bactérias/genética , Coinfecção/diagnóstico , Coinfecção/imunologia , Coinfecção/microbiologia , DNA Bacteriano/genética , Erros de Diagnóstico , Ehrlichiose/microbiologia , Feminino , Febre/diagnóstico , Febre/microbiologia , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Masculino , Pessoa de Meia-Idade , Testes Sorológicos , Carrapatos/microbiologia , Adulto Jovem
16.
J Microbiol Methods ; 150: 5-8, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29746924

RESUMO

OBJECTIVES: Chlamydia trachomatis (CT) IgG serology is used in many fertility clinics in order to estimate the risk for tubal factor infertility (TFI) in the fertility work-up. The predictive value for TFI of the currently used mono-target CT serology test should be improved. This study compares the performance of the new multi-target Mikrogen recomWell CT IgG ELISA with the Mikrogen recomLine CT immunoblot and visualizes distribution of individual antibodies in serum with the immunoblot in order to potentially improve the current CT IgG serology test that is clinically used. METHODS: Study population consisted of 183 Dutch Caucasian infertile women who underwent laparoscopy and/or hysterosalpingography. 48 women had TFI, 135 were controls. Serum was tested with Mikrogen CT IgG ELISA, which detects 3 CT IgG antibodies in one well, and Mikrogen CT immunoblot, which can individually detect 5 CT IgG antibodies. Tests were compared based on the results in general and in the case and control group also taking the individual antibodies into account. Sensitivity, specificity, negative predictive value (NPV), positive predictive value (PPV), Kappa value and distribution of individual antibodies in positive samples were calculated. RESULTS: In 183 patients 51% tested positive in the ELISA versus 35% in the immunoblot. 32% versus 65% tested negative. Difference between PPV was not statistically significant (33% and 39% respectively) and NPV in both tests was 81%. Difference in sensitivity and specificity was statistically significant, respectively 65% vs. 52% and 54% vs. 71%. Kappa was only 45%. 64.5% of samples that tested positive with ELISA were positive for at least 4 individual CT antibodies with the immunoblot. CONCLUSION: The concordance between CT ELISA and CT immunoblot is moderate. Due to separate criteria for positivity of both tests there is a significant difference in sensitivity and specificity. PPV and NPV, the most relevant characteristics for clinicians, of both tests did not differ significantly. The distribution of individual antibodies and the adjustment of the immunoblot algorithm will be further explored in the future in order to develop a potentially better prediction method for TFI with a higher clinical accuracy.


Assuntos
Anticorpos Antibacterianos/sangue , Infecções por Chlamydia/diagnóstico , Chlamydia trachomatis/imunologia , Ensaio de Imunoadsorção Enzimática/métodos , Immunoblotting/métodos , Imunoglobulina G/sangue , Infertilidade Feminina/diagnóstico , Anticorpos Antibacterianos/isolamento & purificação , Infecções por Chlamydia/microbiologia , Chlamydia trachomatis/patogenicidade , Ensaio de Imunoadsorção Enzimática/instrumentação , Feminino , Humanos , Immunoblotting/instrumentação , Imunoglobulina G/isolamento & purificação , Infertilidade Feminina/microbiologia , Países Baixos , Sensibilidade e Especificidade , Testes Sorológicos/métodos
17.
mBio ; 9(2)2018 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-29615497

RESUMO

Carbapenem-resistant (CR) sequence type 258 (ST258) Klebsiella pneumoniae has become an urgent health care threat, causing an increasing number of high-mortality infections. Its resistance to numerous antibiotics and threat to immunocompromised patients necessitate finding new therapies to combat these infections. Previous successes in the laboratory, as well as the conservation of capsular polysaccharide (CPS) among the members of the ST258 clone, suggest that monoclonal antibody (MAb) therapy targeting the outer polysaccharide capsule of K. pneumoniae could serve as a valuable treatment alternative for afflicted patients. Here, we isolated several IgG antibodies from mice inoculated with a mixture of CR K. pneumoniae CPS conjugated to anthrax protective antigen. Two of these MAbs, 17H12 and 8F12, bind whole and oligosaccharide epitopes of the CPS of clade 2 ST258 CR K. pneumoniae, which is responsible for the most virulent CR K. pneumoniae infections in the United States. These antibodies were shown to agglutinate all clade 2 strains and were also shown to promote extracellular processes killing these bacteria, including biofilm inhibition, complement deposition, and deployment of neutrophil extracellular traps. Additionally, they promoted opsonophagocytosis and intracellular killing of CR K. pneumoniae by human-derived neutrophils and cultured murine macrophages. Finally, when mice were intratracheally infected with preopsonized clade 2 CR K. pneumoniae, these MAbs reduced bacterial dissemination to organs. Our data suggest that broadly reactive anticapsular antibodies and vaccines against clade 2 ST258 CR K. pneumoniae are possible. Such MAbs and vaccines would benefit those susceptible populations at risk of infection with this group of multidrug-resistant bacteria.IMPORTANCE Carbapenem-resistant Klebsiella pneumoniae is an enteric bacterium that has been responsible for an increasing number of deadly outbreaks and hospital-acquired infections. The pathogen's resistance to numerous antibiotics, including new drugs, leaves few therapeutic options available for infected patients, who often are too sick to fight the infection themselves. Immunotherapy utilizing monoclonal antibodies has been successful in other medical fields, and antibodies targeting the outer polysaccharide capsule of these bacteria could be a valuable treatment alternative. This study presents two anticapsular antibodies, 17H12 and 8F12, that were found to be protective against the most virulent carbapenem-resistant K. pneumoniae clinical strains. These antibodies are shown to promote the killing of these strains through several extracellular and intracellular processes and prevent the spread of infection in mice from the lungs to distal organs. Thus, they could ultimately treat or protect patients infected or at risk of infection by this multidrug-resistant bacterium.


Assuntos
Anticorpos Antibacterianos/administração & dosagem , Infecções por Klebsiella/terapia , Klebsiella pneumoniae/imunologia , Polissacarídeos Bacterianos/imunologia , Testes de Aglutinação , Estruturas Animais/microbiologia , Animais , Anticorpos Antibacterianos/isolamento & purificação , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/isolamento & purificação , Enterobacteriáceas Resistentes a Carbapenêmicos/imunologia , Células Cultivadas , Modelos Animais de Doenças , Imunoglobulina G/administração & dosagem , Imunoglobulina G/isolamento & purificação , Macrófagos/imunologia , Macrófagos/microbiologia , Camundongos , Neutrófilos/imunologia , Neutrófilos/microbiologia , Fagocitose , Resultado do Tratamento
18.
J Microbiol Methods ; 147: 56-58, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29501689

RESUMO

PURPOSE: Serological testing for antibodies to Chlamydia trachomatis pgp3 is being evaluated as a tool to use for trachoma surveillance. There are limited data on the reproducibility of the test results using a multiplex platform. METHODS: We tested the reproducibility of a serologic test for C. trachomatis pgp3 in 6 dried blood spots collected from a random sample of 45 children from a trachoma endemic area. The spots were tested on a multiplex bead array platform, using one bead set twice, using another bead set at the same time as the first, and using the same bead set twice on different days separated by several months. Seropositivity was defined using ROC analyses from the same external controls for both bead sets. We compared the mean fluorescent intensity unit minus background (MFI-BG) results using the intraclass correlation coefficient (ICC), and analyzed the concordance of seropositivity designation using the kappa statistic. RESULTS: The tests using the same bead set were highly correlated, ICC = 0.997 (0.995-1.00). Even tested months apart, the slight loss of signal was not statistically significant (p = 0.06). The test of the two different bead sets showed high correlation, but the differences in MFI-BG was statistically significant. However, the serostatus of the children was unchanged comparing the seropositivity using one bead set compared to a second bead set. CONCLUSION: The reproducibility of the multiplex bead array for serological testing of antibodies to Chlamydia trachomatis pgp3 is high when the same bead set is used for testing.


Assuntos
Anticorpos Antibacterianos/isolamento & purificação , Antígenos de Bactérias/imunologia , Antígenos de Bactérias/isolamento & purificação , Proteínas de Bactérias/imunologia , Proteínas de Bactérias/isolamento & purificação , Chlamydia trachomatis/imunologia , Testes Sorológicos/métodos , Tracoma/imunologia , Anticorpos Antibacterianos/sangue , Criança , Chlamydia trachomatis/isolamento & purificação , Chlamydia trachomatis/patogenicidade , Humanos , Reprodutibilidade dos Testes , Fatores de Tempo , Tracoma/diagnóstico , Tracoma/microbiologia
20.
Sex Transm Dis ; 45(1): 35-38, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28876300

RESUMO

BACKGROUND: Repeat syphilis is playing an increasing role in syphilis transmission in several populations. The assessment of repeat syphilis and response to treatment depends on accurately measuring intraindividual changes in non-treponemal tests. For a 0- to 6-month delta rapid plasma reagin (RPR) to be determined by routine individual RPR testing, samples are tested 6 months apart with differences in reagent batches, environmental conditions, and observers all leading to measurement errors. We hypothesized that conducting paired RPR testing (simultaneous testing of acute and convalescent samples) would enable a more accurate determination of delta RPR compared with individual testing. METHODS: A total of 120 study participants with a new diagnosis of syphilis were followed up at 0, 3, 6, 9, 12, 18, and 24 months, with RPR testing performed via individual testing at each study visit and at any suspected repeat syphilis. Rapid plasma reagin paired testing was performed on samples from 0 and 6 months and at any suspected repeat syphilis. RESULTS: The quantitative agreement ±1 dilution among paired and individual testing was 97.2%. There was no difference in the proportion with serofast status at 6 months: 21 (19.4%) and 19 (17.6%) according to paired and individual testing, respectively (P = 0.726). There was no statistically significant difference between 0- and 6-month delta RPR as determined by paired and individual testing in predicting seroresponse at 12 months (86.1% and 91.6% agreement with 12-month serofast/nonserofast classification, respectively; P = 0.262). CONCLUSIONS: In our setting, individual testing performed equally well compared with paired testing. Follow-up of syphilis will remain onerous for the patient and the health care provider until new tests that can more accurately assess the response to therapy and repeat syphilis/treatment failure are developed.


Assuntos
Anticorpos Antibacterianos/isolamento & purificação , Fatores Imunológicos/sangue , Kit de Reagentes para Diagnóstico , Reaginas/sangue , Sorodiagnóstico da Sífilis/métodos , Sífilis/diagnóstico , Treponema pallidum/isolamento & purificação , Adulto , Feminino , Seguimentos , Humanos , Masculino , Programas de Rastreamento/métodos , Programas de Rastreamento/normas , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Recidiva , Reprodutibilidade dos Testes , Comportamento Sexual , Sífilis/imunologia , Sorodiagnóstico da Sífilis/normas
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