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1.
Infect Dis Poverty ; 9(1): 19, 2020 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-32051036

RESUMO

BACKGROUND: Mycobacterium leprae and Toxoplasma gondii infections are both neglected tropical diseases highly prevalent in Brazil. Infection with certain parasite species can significantly alter susceptibility to other important pathogens, and/or influence the development of pathology. Here we investigated the possible influence of M. leprae/T. gondii co-parasitism on the manifestation of leprosy and its clinical forms. METHODS: Participants (n = 291) were recruited in Campos dos Goytacazes city, Rio de Janeiro state, southeast Brazil, from August 2015 to December 2019 and clinically diagnosed for leprosy. Participants were selected based on the presence (patients) or absence (healthy controls) of the leprosy disease. Contacts of patients were also recruited for this study. Serum samples from patients (n = 199) with leprosy, contacts (n = 40) and healthy controls (n = 52) were investigated for levels of IgM and IgG anti-phenolic glycolipid-1 (PGL-1) by ELISA. Additionally, IgG antibody against soluble Toxoplasma antigen (STAg) was measured in sera samples from leprosy patients, contacts and healthy controls for Toxoplasma gondii serology by ELISA. Anti-PGL-1 IgG and IgM levels were compared using one-way ANOVA Kruskal-Wallis or Mann-Whitney, while Spearman test was used to correlate levels of IgG anti-STAg and IgM/IgG anti-PGL-1 from seropositive and seronegative individuals for T. gondii infection. The risk of T. gondii infection for leprosy disease was assessed using Fisher's test. RESULTS: Levels of IgM anti-PGL-1 antibodies were significantly higher in multibacillary (MB) patients compared to paucibacillary (PB) patients (P = 0.0068). Higher IgM and IgG levels anti-PGL-1 were detected in patients with the lepromatous forms. The serologic prevalence for T. gondii infection was 74.9%. We detected increased anti-STAg antibody levels in leprosy patients (79.4%), reaching 88.8% within those with lepromatous form of this disease. The leprosy risk increase in T. gondii seropositive individuals was two-fold (odds ratio [OR] = 2.055; 95% confidence intervals [95% CI]: 1.18-3.51) higher than those seronegative, and considering the lepromatous leprosy risk this increase was even dramatic (OR = 4.33; 95% CI: 1.76-9.69) in T. gondii seropositive individuals. Moreover the leprosy risk in T. gondii seropositive individuals was weakly correlated to the levels of IgG anti-STAg and IgM/IgG anti-PGL-1. CONCLUSIONS: Altogether, our results suggest that T. gondii infection may exert immunomodulatory properties that influence to the susceptibility of leprosy, mainly on its more severe clinical form. A better understanding of parasite immunomodulation can ultimately contribute to the development of medical applications.


Assuntos
Anticorpos Antibacterianos/sangue , Hanseníase Virchowiana/epidemiologia , Mycobacterium leprae/imunologia , Toxoplasma/imunologia , Toxoplasmose/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Brasil/epidemiologia , Estudos de Casos e Controles , Criança , Comorbidade , Ensaio de Imunoadsorção Enzimática , Feminino , Glicolipídeos/imunologia , Humanos , Imunoglobulina G/imunologia , Imunoglobulina M/imunologia , Masculino , Pessoa de Meia-Idade , Estudos Soroepidemiológicos , Adulto Jovem
2.
Cell Host Microbe ; 27(2): 161-163, 2020 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-32053783

RESUMO

Invertebrates molt, furry mammals shed, and human skin exfoliates. In this issue of Cell Host & Microbe, Zingl et al. describe a virulence mechanism in which the bacterial pathogen Vibrio cholerae jettisons outer membrane proteins and lipids in vesicles as it enters the mammalian intestine.


Assuntos
Vibrio cholerae , Animais , Anticorpos Antibacterianos , Humanos , Intestinos , Virulência , Fatores de Virulência
3.
Zhonghua Yu Fang Yi Xue Za Zhi ; 54(2): 203-208, 2020 Feb 06.
Artigo em Chinês | MEDLINE | ID: mdl-32074711

RESUMO

Objective: Meta-analysis was conducted on the tetanus antibody protection rate of healthy population born after 1978 in China (data from Hong Kong, Macao and Taiwan was excluded, the same below). Methods: Search the data on China's tetanus antibody level which were published in China National Knowledge Infrastructure, Wanfang data, VIP, SinoMed database, PubMed and the Cochrane Library. The Chinese search keywords were "Tetanus Antitoxin", "Tetanus Antibody", "Healthy Population" and "Mainland China". English search terms include "tetanus antitoxin", "tetanus vaccine", "tetanus vaccine", "general population" and "mainland of China". The time limit for inclusion in literature research was 2010-2019. Stata software was used to conduct meta-analysis on the protection rate of tetanus antibody. Results: A total of 24 articles were included. There was no obvious publication bias in the included articles. The total number of respondents was 23 530, the antibody protection rate was 49.5%-99.0%. A total of 20 817 people got effective antibody protection, which meant the antibody level reached and exceeded 0.1 IU/ml, and the combined protection rate was 78.6% (95%CI: 75.0%-88.2%). The combined protection rates of antibody in 0-7 years old and 8-15 years old groups were 88.9% (95%CI: 86.9%-91.0%) and 79.3% (95%CI: 72.9%-86.2%) respectively. The combined protection rates of antibodies in 16-20 years old, 21-30 years old and 31-40 years old groups were 58.9% (95%CI: 46.5%-71.2%), 47.7% (95%CI: 16.8%-78.7%) and 63.8% (95%CI:32.6%-95.1%) respectively. The combined protection rate of tetanus antibody for 0-15 years old people was 85.6% (95%CI: 83.1%-88.1%), and the combined protection rate of antibody for 16-40 years old people was 52.9% (95%CI: 39.3%-66.6%). Conclusion: With the increase of age, the protection rate of tetanus antibody among the healthy population aged 16-40 years in our country decreases. An individualized vaccination plan should be formulated according to the previous tetanus vaccination history and the tetanus antibody level when necessary.


Assuntos
Anticorpos Antibacterianos/análise , Tétano/imunologia , Adolescente , Adulto , Criança , Pré-Escolar , China , Humanos , Lactente , Recém-Nascido , Adulto Jovem
4.
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
5.
Life Sci ; 248: 117444, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32084433

RESUMO

AIMS: Nonhuman primates have been used to investigate pathogenic mechanisms and evaluate immune responses following Chlamydia trachomatis inoculation. This study aimed to systemically profile antibody responses to C. trachomatis infection in nonhuman primates. MATERIALS AND METHODS: Sera were obtained from 4 pig-tailed and 8 long-tailed macaques which were intravaginally or ocularly infected with live C. trachomatis organisms, and analyzed by C. trachomatis proteome array of antigens. KEY FINDINGS: The sera from 12 macaques recognized total 172 C. trachomatis antigens. While 84 antigens were recognized by pig-tailed macaques intravaginally infected with serovar D strain, 125 antigens were recognized by long-tailed macaques ocularly infected with serovar A, and 37 antigens were recognized by both. Ocular inoculation with virulent A2497 strain induced antibodies to more antigens. Among the antigens uniquely recognized by A2497 strain infected macaques, outer membrane complex B antigen (OmcB) induced robust antibody response. Although macaques infected by less virulent A/HAR-13 strain failed to develop antibodies to OmcB, reinfection by A2497 strain induced high levels of antibodies to OmcB. SIGNIFICANCE: Proteome array has revealed a correlation of chlamydial infection invasiveness with chlamydial antigen immunogenicity, and identified antibody responses to OmcB potentially as biomarkers for invasive infection with C. trachomatis.


Assuntos
Anticorpos Antibacterianos/biossíntese , Antígenos de Bactérias/sangue , Infecções por Chlamydia/imunologia , Chlamydia trachomatis/imunologia , Infecções do Sistema Genital/imunologia , Tracoma/imunologia , Animais , Anticorpos Antibacterianos/classificação , Antígenos de Bactérias/classificação , Proteínas da Membrana Bacteriana Externa/sangue , Infecções por Chlamydia/sangue , Infecções por Chlamydia/microbiologia , Chlamydia trachomatis/patogenicidade , Olho/imunologia , Olho/microbiologia , Feminino , Soros Imunes/química , Macaca fascicularis , Macaca nemestrina , Masculino , Análise Serial de Proteínas , Proteoma/química , Proteoma/imunologia , Infecções do Sistema Genital/sangue , Infecções do Sistema Genital/microbiologia , Tracoma/sangue , Tracoma/microbiologia , Vagina/imunologia , Vagina/microbiologia
6.
BMC Infect Dis ; 20(1): 26, 2020 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-31918671

RESUMO

BACKGROUND: Human brucellosis is an infectious zoonotic disease caused by Brucella spp. It is one of the most public health problems that remains largely neglected in developing counties, including Saudi Arabia. Brucellosis is particularly prevalent among rural people who have constant contact with livestock. METHODS: A cross-sectional sero-epidemiological study conducted in Aseer Central Hospital, South Saudi Arabia, between 2014 and 2018 among 7567 patients. Serum samples were analyzed for Brucella antibodies using slide agglutination test. Serology results and patient's demographic data were analyzed by GraphPad Prism. Results were presented as mean ± SEM and differences between two groups were assessed by t-test and p < 0.05 was considered significant. RESULTS: The prevalence of brucellosis among the admitted suspected 7567 cases was 12.8% (10.4-15.7%; CI 95%). The highest prevalence rate was detected during 2015, the rate decreased to the lowest level during the last three years (p < 0.05). Higher rate of brucellosis was observed among males than females (p < 0.05) and most cases were reported during summer season (p < 0.05). The highest prevalence rate was observed in age group 21-40 year old (40.5%) followed by 41-60 years (27.7%). The lowest prevalence rate was noticed in old and young children (15 and 3%, respectively). Cross-transmission of brucellosis was seen within family (1%) and high titers (> 1280) was noticed in 22% of the hospitalized patients. The major symptoms were fatigue, hyperhidrosis, fever and joint pain. CONCLUSION: Our findings showed a high prevalence of human brucellosis among suspected patients in Aseer region. This indicates that clinical suspicion is a valid criterion and the endemic nature of the disease. The disease status requires early laboratory detection and confirmation to start prompt treatment to decrease patients suffering.


Assuntos
Brucella/imunologia , Brucelose/epidemiologia , Encaminhamento e Consulta , Zoonoses/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Testes de Aglutinação , Animais , Anticorpos Antibacterianos/sangue , Brucelose/microbiologia , Criança , Pré-Escolar , Estudos Transversais , Feminino , Humanos , Lactente , Gado/microbiologia , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Retrospectivos , Fatores de Risco , População Rural , Arábia Saudita/epidemiologia , Estações do Ano , Estudos Soroepidemiológicos , Adulto Jovem , Zoonoses/microbiologia
7.
BMC Infect Dis ; 20(1): 11, 2020 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-31906870

RESUMO

BACKGROUND: Brucellosis is endemic in many areas in China. The current diagnosis of Brucellosis predominantly relies on the traditional bacterial culture and serum agglutination test. In this study, we aimed to explore the value of ELISA in the diagnosis of Brucellosis in Chinese population. METHODS: We recruited 235 patients with a diagnosis of Brucellosis at different clinical stages: 117 in acute, 78 in subacute, and 40 in chronic. We also recruited 248 control patients who presented with similar clinical symptoms but with a different diagnosis other than Brucellosis. In addition, 90 healthy volunteers were also recruited. Bacterial culture, agglutination test and ELISA assay were performed to detect Brucella spp. RESULTS: Among 235 patients with Brucellosis, 51 (21.7%) was positive for bacterial culture, 150 (63.8%) were positive by agglutination test, and 232 (98.7%) were positive by ELISA (IgG and/or IgM). When we stratified the patients based on the disease stages (acute, subacute and chronic), ELISA was the most sensitive method and showed a highest positive rate in all stages. By Receiver Operating Characteristic Curve analysis of ELISA results, we found that measurement of IgG level was superior to measurement of IgM level (AUC, 0.993 versus 0.877). Since the measurement of IgG itself missed rare cases in acute phase, we recommended measuring IgG and IgM simultaneously by ELISA for the diagnosis of Brucellosis. In term of the specificity of ELISA in the diagnosis of Brucellosis, our study showed that only 1.6% (4/248) non-Brucellosis patients were positive by ELISA; all positive cases were IgM only and none showed positive IgG. Similar results were found in healthy volunteers. In summary, our study concluded that ELISA is the most sensitive and specific method to detect Brucellosis in Chinese population. CONCLUSIONS: ELISA assay is sensitive, fast, and convenient to detect Brucellosis. It shows the high sensitivity and specifity and should be used as a routine lab test when Brucellosis is suspected in clinical practice.


Assuntos
Técnicas Bacteriológicas/métodos , Técnicas Bacteriológicas/normas , Brucella/isolamento & purificação , Brucelose/diagnóstico , Ensaio de Imunoadsorção Enzimática/normas , Adulto , Idoso , Testes de Aglutinação/normas , Anticorpos Antibacterianos/sangue , Brucella/crescimento & desenvolvimento , Brucella/imunologia , Brucelose/sangue , Brucelose/microbiologia , China , Feminino , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade
8.
Orv Hetil ; 161(2): 50-55, 2020 Jan.
Artigo em Húngaro | MEDLINE | ID: mdl-31902236

RESUMO

Introduction: Exudative tonsillitis is a common clinical picture during childhood. The majority of these cases are caused by viruses (Epstein-Barr virus [EBV], cytomegalovirus [CMV], influenza virus, parainfluenza virus, and adenovirus), and only some infections are caused by bacteria, mainly group A streptococci (GAS). On the basis of international guidelines, routine use of early antibiotic treatment is not recommended in these cases, because it seems not to prevent GAS-associated complications. Aim: Our aim was to determine those laboratory results which are useful to distinguish between bacterial and viral infections in children with exudative tonsillitis to reduce antibiotic overuse. Method: In our study, we evaluated 135 clinical data from 133 children with exudative tonsillitis. Patients were grouped according to the following criteria: the first group contained patients with acute CMV or EBV infections, while in the second group, CMV or EBV infections were not confirmed using serology. Results: On the basis of our results, EBV or CMV infections (66/135, 48.8%) were serologically confirmed in the majority of cases with exudative tonsillitis between 2016 and 2017, while the causative role of GAS was minimal in this patient group (3/65, 4.61%). In spite of this finding, the majority of patients (92%) were treated with antibiotics. Conclusion: Our retrospective findings confirmed that it is not possible to determine the causative agent of this clinical picture on the basis of symptoms, and physical findings, moreover laboratory results, such as high white blood cell count could not confirm bacterial infection. At the same time, elevated transaminase levels may refer to viral origin of infection, especially EBV or CMV with high predictive value; the use of extended laboratory tests may reduce the unnecessary antibiotic consumption. Orv Hetil. 2020; 161(2): 50-55.


Assuntos
Infecções Estreptocócicas/etiologia , Tonsilite/etiologia , Viroses/etiologia , Antibacterianos/uso terapêutico , Anticorpos Antibacterianos/análise , Anticorpos Antivirais/análise , Infecções Bacterianas/diagnóstico , Infecções Bacterianas/tratamento farmacológico , Criança , Humanos , Faringe/microbiologia , Faringe/virologia , Estudos Retrospectivos , Tonsilite/tratamento farmacológico , Viroses/diagnóstico , Viroses/tratamento farmacológico
9.
Infect Immun ; 88(2)2020 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-31818965

RESUMO

The sialylatable lacto-N-neotetraose (LNnT; Gal-GlcNAc-Gal-Glc) moiety from heptose I (HepI) of the lipooligosaccharide (LOS) of Neisseria gonorrhoeae undergoes positive selection during human infection. Lactose (Gal-Glc) from HepII, although phase variable, is commonly expressed in humans; loss of HepII lactose compromises gonococcal fitness in mice. Anti-LOS monoclonal antibody (MAb) 2C7, a promising antigonococcal immunotherapeutic that elicits complement-dependent bactericidal activity and attenuates gonococcal colonization in mice, recognizes an epitope comprised of lactoses expressed simultaneously from HepI and HepII. Glycan extensions beyond lactose on HepI modulate binding and function of MAb 2C7 in vitro Here, four gonococcal LOS mutants, each with lactose from HepII but fixed (unable to phase-vary) LOS HepI glycans extended beyond the lactose substitution of HepI (lactose alone, Gal-lactose, LNnT, or GalNAc-LNnT), were used to define how HepI glycan extensions affect (i) mouse vaginal colonization and (ii) efficacy in vitro and in vivo of a human IgG1 chimeric derivative of MAb 2C7 (2C7-Ximab) with a complement-enhancing E-to-G Fc mutation at position 430 (2C7-Ximab-E430G). About 10-fold lower 2C7-Ximab-E430G concentrations achieved similar complement-dependent killing of three gonococcal mutants with glycan extensions beyond lactose-substituted HepI (lactose alone, LNnT, or GalNAc-LNnT) as 2C7-Ximab (unmodified Fc). The fourth mutant (Gal-lactose) resisted direct complement-dependent killing but was killed approximately 70% by 2C7-Ximab-E430G in the presence of polymorphonuclear leukocytes and complement. Only mutants with (sialylatable) LNnT from HepI colonized mice for >3 days, reiterating the importance of LNnT sialylation for infection. 2C7-Ximab-E430G significantly attenuated colonization caused by the virulent mutants.


Assuntos
Anticorpos Antibacterianos/uso terapêutico , Anticorpos Monoclonais Humanizados/uso terapêutico , Anticorpos Monoclonais/uso terapêutico , Gonorreia/terapia , Lipopolissacarídeos/imunologia , Neisseria gonorrhoeae/imunologia , Animais , Modelos Animais de Doenças , Feminino , Camundongos Endogâmicos BALB C , Resultado do Tratamento , Vagina/microbiologia
10.
Plant Mol Biol ; 102(1-2): 159-169, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31820286

RESUMO

KEY MESSAGE: A plant-based multiepitopic protein (LTBentero) containing epitopes from ETEC, S. typhimurium, and V. parahaemolyticus was produced in plants cells and triggered systemic and intestinal humoral responses in immunized mice. Around 200 million people suffer gastroenteritis daily and more than 2 million people die annually in developing countries due to such pathologies. Vaccination is an alternative to control this global health issue, however new low-cost vaccines are needed to ensure proper vaccine coverage. In this context, plants are attractive hosts for the synthesis and delivery of subunit vaccines. Therefore, in this study a plant-made multiepitopic protein named LTBentero containing epitopes from antigens of enterotoxigenic E. coli, S. typhimurium, and V. parahaemolyticus was produced and found immunogenic in mice. The LTBentero protein was expressed in tobacco plants at up to 5.29 µg g-1 fresh leaf tissue and was deemed immunogenic when administered to BALB/c mice either orally or subcutaneously. The plant-made LTBentero antigen induced specific IgG (systemic) and IgA (mucosal) responses against LTB, ST, and LptD epitopes. In conclusion, multiepitopic LTBentero was functionally produced in plant cells, being capable to trigger systemic and intestinal humoral responses and thus it constitutes a promising oral immunogen candidate in the fight against enteric diseases.


Assuntos
Toxinas Bacterianas/imunologia , Epitopos/imunologia , Imunização , Proteínas de Plantas/imunologia , Proteínas Recombinantes/imunologia , Vacinas de Plantas Comestíveis/imunologia , Animais , Anticorpos Antibacterianos/imunologia , Toxinas Bacterianas/genética , Vacinas Bacterianas/imunologia , Escherichia coli Enterotoxigênica/genética , Escherichia coli Enterotoxigênica/imunologia , Epitopos/genética , Feminino , Regulação da Expressão Gênica de Plantas , Imunoglobulina A , Imunoglobulina G , Camundongos , Camundongos Endogâmicos BALB C , Membrana Mucosa/imunologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/imunologia , Plantas Geneticamente Modificadas/metabolismo , Proteínas Recombinantes/metabolismo , Tabaco/genética , Vacinação , Vacinas de Plantas Comestíveis/genética
11.
J Appl Microbiol ; 128(1): 102-115, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31596989

RESUMO

AIM: This work reports a new method for the use of lasers for the selective killing of bacteria targeted using light-absorbing Silver nanoparticles (Ag-NPs) conjugated with a specific antibody against the Gram-positive bacterium Staphylococcus aureus (S. aureus). METHODS AND RESULTS: Ag-NPs were synthesized using a chemical reduction method and characterized with respect to their surface plasmon resonance, surface morphology via transmission electron microscopy (TEM) and dynamic light scattering (DLS). The bacterial surface was targeted using 20 nm Ag-NPs conjugated with an anti-protein A antibody. Labelled bacteria were irradiated with blue visible laser at 2·04 W/cm2 . The antibacterial activity of functionalized Ag-NPs was investigated by fluorescence microscopy after irradiation, and morphological changes in S. aureus after laser treatment were assessed using scanning electron microscopy (SEM). The laser-irradiated, functionalized Ag-NPs exhibited significant bactericidal activity, and laser-induced bacterial damage was observed after 10 min of laser irradiation against S. aureus. The fluorescence microscopic analysis results supported that bacterial cell death occurred in the presence of the functionalized Ag-NPs. CONCLUSIONS: The results of this study suggest that a novel method for the preparation of functionalized nanoparticles has potential as a potent antibacterial agent for the selective killing of resistant disease-causing bacteria. SIGNIFICANCE AND IMPACT OF THE STUDY: This study shows that Ag-NPs functionalized with a specific antibody, could be used in combination with laser radiation as a novel treatment to target resistant bacterial and fungal pathogens with minimal impact on normal microflora.


Assuntos
Antibacterianos/farmacologia , Anticorpos Antibacterianos/química , Nanopartículas Metálicas/química , Prata/química , Staphylococcus aureus/efeitos dos fármacos , Antibacterianos/química , Antibacterianos/efeitos da radiação , Lasers , Testes de Sensibilidade Microbiana , Prata/farmacologia , Especificidade da Espécie , Proteína Estafilocócica A/imunologia , Staphylococcus aureus/imunologia , Propriedades de Superfície
12.
Ann Lab Med ; 40(1): 68-71, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31432642

RESUMO

Evaluation of diagnostic tests requires reference standards, which are often unavailable. Latent class analysis (LCA) can be used to evaluate diagnostic tests without reference standards, using a combination of observed and estimated results. Conditionally independent diagnostic tests for Helicobacter pylori infection are required. We used LCA to construct a reference standard and evaluate the capability of non-invasive tests (stool antigen test and serum antibody test) to diagnose H. pylori infection compared with the conventional method, where histology is the reference standard. A total of 96 healthy subjects with endoscopy histology results were enrolled from January to July 2016. Sensitivity and specificity were determined for the LCA approach (i.e., using a combination of three tests as the reference standard) and the conventional method. When LCA was used, sensitivity and specificity were 83.8% and 99.4% for histology, 80.0% and 81.9% for the stool antigen test, and 63.6% and 89.3% for the serum antibody test, respectively. When the conventional method was used, sensitivity and specificity were 75.8% and 71.1% for the stool antigen test and 77.7% and 60.7% for the serum antibody test, respectively. LCA can be applied to evaluate diagnostic tests that lack a reference standard.


Assuntos
Infecções por Helicobacter/diagnóstico , Helicobacter pylori/isolamento & purificação , Análise de Classes Latentes , Anticorpos Antibacterianos/sangue , Antígenos/análise , Fezes/química , Gastroscopia , Infecções por Helicobacter/microbiologia , Helicobacter pylori/imunologia , Helicobacter pylori/metabolismo , Humanos , Sensibilidade e Especificidade
13.
Food Chem ; 309: 125690, 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-31711808

RESUMO

In this work a new fluorescence immunosensor with use of graphene oxide and graphene quantum dot for detection Campylobacter jejuni whole cell in food samples was designed. This biosensor was designed based on interaction of poly clonal antibody conjugated with graphene quantum dot with surface protein in Campylobacter jejuni cell membrane. Specific binding of graphene quantum dot with Campylobacter jejuni membrane leads to generate a distance among graphene dot and graphene oxide and fluorescence is ON. In lack of Campylobacter jejuni or in existence of other bacterial cells, distance between of graphene dot and graphene oxide is very low and graphene quantum dot fluorescence emission was OFF. Experiment revealed that step by step increase in bacterial target cells caused to gradually increased fluorescence emission and this process was linear. Limit of detection for this bacterial sensor was 10 CFU/ml and ability of this FRET immunosensor for Campylobacter jejuni sensing in comparison with other bacterial cells was significant. Also, this method for monitoring Campylobacter jejuni in poultry liver was applied and results revealed that this immunosensor could be used for analysis bacterial cell in food samples.


Assuntos
Técnicas Biossensoriais/métodos , Campylobacter jejuni/isolamento & purificação , Grafite/química , Pontos Quânticos/química , Animais , Anticorpos Antibacterianos/química , Anticorpos Antibacterianos/imunologia , Proteínas da Membrana Bacteriana Externa/imunologia , Campylobacter jejuni/metabolismo , Transferência Ressonante de Energia de Fluorescência , Microbiologia de Alimentos , Limite de Detecção , Fígado/microbiologia , Aves Domésticas/microbiologia
14.
PLoS Negl Trop Dis ; 13(12): e0007793, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31790399

RESUMO

This study describes changes in the prevalence of Leptospira interrogans infections among small mammals, including rats and larger domestic and wild mammals in Lviv Oblast, a region in western Ukraine from 2001-2015, using the microscopic agglutination test (MAT). A total of 439,948 domestic or wild animals were tested. We found the prevalence of Leptospira interrogans exposure varied among tested species and changed over the time. Infection was significantly less common in domestic animals, than in wild rodents. In swine the overall seroprevalence was 0.51%, while in cattle it was 0.19%. In dogs it was higher-2.75%. After 2006, evidence of infection was only observed in swine among domestic animals. The prevalence among large wild animals (0.25%) was similar to that among domestic animals. Among small mammals and rats, seroprevalence was most commonly observed among Rattus norvegicus (18.44%) and it was less common among other wild small mammals (8.74%). There were two dominant serogroups among large wild and domestic animals-L. icterohaemorrhagiae and L. hebdomadis while among wild small mammals the two most common were L. icterohaemorrhagiae and L. grippotyphosa. Wild animals with antibodies were found throughout the entire oblast.


Assuntos
Doenças dos Animais/epidemiologia , Doenças dos Animais/microbiologia , Anticorpos Antibacterianos/sangue , Leptospira interrogans/imunologia , Leptospirose/veterinária , Mamíferos , Animais , Animais Domésticos , Animais Selvagens , Leptospirose/epidemiologia , Leptospirose/microbiologia , Estudos Soroepidemiológicos , Ucrânia/epidemiologia
15.
PLoS One ; 14(12): e0226246, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31877160

RESUMO

The aim of our study was to evaluate the flock sensitivity and specificity of fecal qPCR and serum ELISA using pooled samples for screening paratuberculosis in French sheep. Using individual feces with low or high qPCR Ct values from ewes sampled in 14 infected flocks, a total of 555 pools of size 5, 10 and 20 were created by diluting individual materials in negative feces and analysed using a commercial IS900 qPCR kit. The relative performances of pooled serum ELISA analysis were evaluated based on the analysis of 181 different pools of size 5 and 10, composed of individual serum samples of various individual S/P values. Results showed that for pools of size 5, 10 or 20, individual fecal samples with low Ct values were invariably detected. Conversely fecal samples with high Ct values were associated with a lower detection rate in both pools of size 5 (87.0% to 90.0%), 10 (63.0% to 70.7%) and 20 (46.7% to 60.0%). After lowering the decision threshold to 25% and 15% for serum pools of size 5 and 10 respectively, the pooled serum ELISA relative sensitivity ranged between 62.2% and 100.0% depending on the composition of the pools. Finally, a simulation study was carried out to evaluate the performances of 16 screening strategies at flock level, with varying pool size (5 to 20) and number (5 to 60). The use of pooled serum ELISA led to very false positive detection rate ranging between 37.6% and 91.8% in paratuberculosis free flocks and prevents its further use in that context. For infection prevalence ≤ 5%, the flock sensitivity based on pooled fecal qPCR ranged between 39.0% (5 pools of size 10) and 99.9% (300 sampled individuals, with pools of size 5,10 or20), and was always above 93% when the infection prevalence was greater or equal to 15%. We conclude that pooled-fecal qPCR but not pooled-serum ELISA could be a useful tool to detect sheep flocks infected with paratuberculosis.


Assuntos
Anticorpos Antibacterianos/sangue , Fezes/microbiologia , Mycobacterium avium subsp. paratuberculosis/genética , Paratuberculose/diagnóstico , Doenças dos Ovinos/microbiologia , Animais , Estudos Transversais , Diagnóstico Precoce , Ensaio de Imunoadsorção Enzimática/veterinária , Mycobacterium avium subsp. paratuberculosis/imunologia , Paratuberculose/diagnóstico por imagem , Prevalência , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Sensibilidade e Especificidade , Ovinos , Doenças dos Ovinos/epidemiologia , Manejo de Espécimes
16.
Pol J Microbiol ; 68(3): 295-302, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31880874

RESUMO

The article presents data on serological studies of 573 sera samples of cattle that were collected from the farms affected by leptospirosis in different regions of Ukraine in the period of 2014-2015. Samples were investigated by the microscopic agglutination test (MAT), which was conducted within eight serological groups of Leptospira and nine serovars: Sejroe (serovars polonica and hardjo), Hebdomadis (serovar kabura), Tarassovi (serovar tarassovi), Pomona (serovar pomona), Grippotyphosa (serovar grippotyphosa), Canicola (serovar canicola), Icterohaemorrhagiae (serovar copenhageni), and Australis (serovar bratislava). The circulation of L. interrogans serovar hardjo among cattle has been observed in all 11 regions of Ukraine investigated within 25.8-60.0% of the leptospirosis-positive serum samples in these regions. Antibodies in the cattle sera against serovar hardjo (serogroup Sejroe) were detected in 139 of the 370 cows reacting positively in MAT. Overall, they were detected in 24.3% animals out of the total of 573 cows investigated. These are the preliminary results, however, in our opinion, they should allow to include the serovar hardjo in a standard panel of strains for MAT in Ukraine.The article presents data on serological studies of 573 sera samples of cattle that were collected from the farms affected by leptospirosis in different regions of Ukraine in the period of 2014­2015. Samples were investigated by the microscopic agglutination test (MAT), which was conducted within eight serological groups of Leptospira and nine serovars: Sejroe (serovars polonica and hardjo), Hebdomadis (serovar kabura), Tarassovi (serovar tarassovi), Pomona (serovar pomona), Grippotyphosa (serovar grippotyphosa), Canicola (serovar canicola), Icterohaemorrhagiae (serovar copenhageni), and Australis (serovar bratislava). The circulation of L. interrogans serovar hardjo among cattle has been observed in all 11 regions of Ukraine investigated within 25.8­60.0% of the leptospirosis-positive serum samples in these regions. Antibodies in the cattle sera against serovar hardjo (serogroup Sejroe) were detected in 139 of the 370 cows reacting positively in MAT. Overall, they were detected in 24.3% animals out of the total of 573 cows investigated. These are the preliminary results, however, in our opinion, they should allow to include the serovar hardjo in a standard panel of strains for MAT in Ukraine.


Assuntos
Anticorpos Antibacterianos/sangue , Doenças dos Bovinos/sangue , Leptospira interrogans/imunologia , Leptospirose/veterinária , Testes de Aglutinação , Animais , Bovinos , Doenças dos Bovinos/microbiologia , Feminino , Leptospira interrogans/classificação , Leptospira interrogans/genética , Leptospira interrogans/isolamento & purificação , Leptospirose/sangue , Leptospirose/microbiologia , Masculino , Sorogrupo , Ucrânia
17.
Ig Sanita Pubbl ; 75(4): 317-325, 2019.
Artigo em Italiano | MEDLINE | ID: mdl-31887737

RESUMO

The possible risk of hyperimmunization after tetanus vaccination is currently discussed after the National Vaccine Prevention Plan 2017-2019 confirmed the recommendation of a booster dose every ten years. Due to the ubiquitous nature of tetanus spores and the inability to obtain herd-immunity through vaccination, efforts to reduce the incidence of tetanus aim at eliminating the disease. The only way to prevent infection is vaccination followed by recommended periodic booster doses. Between 2012 and 2016, Italy notified 45% (252/564) of all cases reported by the 26 EU Member States, most of them in the over 65 age group, generally women in the rural areas. The recommendation of the antipertussis vaccine, combined with anti-tetanus, in pregnancy and the indications for antitetanic prophylaxis by vaccination or specific immunoglobulins in emergency setting, gives rise to doubts about the risk of hyperimmunization. Studies generally agree on the safety of diphtheria-tetanus-pertussis combined vaccines during the third trimester of pregnancy, and the time elapsed since the previous tetanus vaccination seems not to be related to significant differences in the incidence of adverse events or obstetrical complications. In the emergency wards, given the relatively high incidence of tetanus in Italy, the risk/benefit ratio often leads to prefer vaccination to no-intervention. The administration of tetanus immunoglobulins in subjects not vaccinated in the last 10 years seems justified by the epidemiology of tetanus in Italy.


Assuntos
Vacinas contra Difteria, Tétano e Coqueluche Acelular/efeitos adversos , Vacinas contra Difteria, Tétano e Coqueluche Acelular/imunologia , Difteria/prevenção & controle , Imunização Secundária/efeitos adversos , Tétano/prevenção & controle , Coqueluche/prevenção & controle , Anticorpos Antibacterianos/imunologia , Difteria/imunologia , Vacinas contra Difteria, Tétano e Coqueluche Acelular/administração & dosagem , Feminino , Humanos , Itália , Tétano/imunologia , Coqueluche/imunologia
18.
BMC Infect Dis ; 19(1): 1001, 2019 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-31775645

RESUMO

BACKGROUND: Q fever has been associated with perinatal complications. We conducted a prospective follow-up study to assess both the incidence of adverse pregnancy outcomes (APOs) associated with Coxiella burnetii infection and the contribution of Q fever to APOs. METHODS: Between May 1 and October 31, 2013, within the regional perinatal health care centre of Saint Pierre, Reunion island, we investigated unexplained miscarriages, stillbirths, preterm births or small-for-gestational age children. Seropositivity for C. burnetii antibodies was defined using indirect immunofluorescence for a phase 2 IgG titre ≥1:64. Acute Q fever was defined for a high phase 2 IgG titre ≥1:256 (compatible with recent or active infection) or the detection of C. burnetii genome in miscarriage products and placentas. Incidence rate ratios (IRR) for Q fever related APOs (taken as a composite outcome or individually) were assessed using Poisson regression models for dichotomous outcomes controlling major confounders. RESULTS: Over a 6-month period, 179 pregnant women suspected or diagnosed with an APO were investigated for Q fever, of whom 118 met the definition for an APO. Of these, 19 were seropositive and 10 presented a profile indicative of an acute infection. For three women with an acute Q fever, the chronology between the onset of infection, the APO (2 miscarriages, 1 preterm birth) and the seroconversion suggested causality in the pathogenesis. The cumulative incidence of Q fever related APOs was estimated between 2.2‰ and 5.2‰, whether causality was required or not. Both C. burnetii exposure and acute Q fever were independently associated with APOs (IRR 1.55, 95% CI 1.31-1.84; IRR 1.47, 95% CI 1.15-1.89, respectively). CONCLUSIONS: In the endemic context of Reunion island, acute Q fever may lead to APOs. To limit the burden of Q fever on reproduction, pregnant women should be kept away from farms and avoid direct contact with ruminants.


Assuntos
Coxiella burnetii/genética , Coxiella burnetii/imunologia , Complicações Infecciosas na Gravidez/epidemiologia , Resultado da Gravidez/epidemiologia , Febre Q/epidemiologia , Adolescente , Adulto , Anticorpos Antibacterianos/imunologia , Coxiella burnetii/isolamento & purificação , DNA Bacteriano/genética , Feminino , Técnica Indireta de Fluorescência para Anticorpo , Seguimentos , Humanos , Incidência , Placenta/microbiologia , Gravidez , Estudos Prospectivos , Reação em Cadeia da Polimerase em Tempo Real , Estudos Retrospectivos , Reunião/epidemiologia , Adulto Jovem
19.
Vet Microbiol ; 239: 108447, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31767087

RESUMO

Brucellosis is one of the most common zoonotic diseases worldwide. Almost 500,000 new human cases occur each year; yet there is no vaccine for human use. Moreover, there is no universal Brucella vaccine that would provide protection against all pathogenic species of Brucella. We generated a rough, live-attenuated B. neotomae strain by deleting the wboA gene encoding a glycosyltransferase. This strain lacks the O-side chain in its lipopolysaccharide (LPS) and thus the vaccinated animals can be differentiated serologically from the field-infected animals. We tested the efficacy of rough B. neotomae strain to stimulate dendritic cells compared to the smooth wild type strain. Based on TNF-α production, our data suggests that a significantly higher stimulation was obtained when dendritic cells were stimulated with the rough vaccine strain compared to the smooth wild type B. neotomae. Furthermore, the rough mutant was cleared from mice within 6 weeks even at a dose as high as 2 x 108 CFU. Vaccinated mice showed significantly higher level of protection against a virulent B. suis 1330 challenge compared to the control mice. Antibody titers in the mice and cytokine production by the splenocytes from the vaccinated mice showed a Th1 mediated immune response that correlated with the protection.


Assuntos
Vacina contra Brucelose/imunologia , Brucella/imunologia , Brucelose/prevenção & controle , Animais , Anticorpos Antibacterianos/sangue , Proteínas de Bactérias/genética , Proteínas de Bactérias/imunologia , Brucella/genética , Vacina contra Brucelose/normas , Brucella suis , Brucelose/imunologia , Brucelose/microbiologia , Deleção de Genes , Camundongos , Vacinas Atenuadas/imunologia
20.
Vet Microbiol ; 239: 108487, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31767097

RESUMO

Mannheimia haemolytica colonizes the nasopharynx of cattle and can cause severe fibrinous pleuropneumonia. IgA proteases are metalloendopeptidases released by bacteria that cleave IgA, enhancing colonization of mucosa. The objectives of these studies were to characterize M. haemolytica IgA1 and IgA2 proteases in vitro and in silico, to clone and sequence the genes for these proteases, and to demonstrate immunogenicity of components of the entire IgA protease molecule. Both IgA protease genes were cloned, expressed, and sequenced. Sequences were compared to other published sequences. Components were used to immunize mice to determine immunogenicity. Sera from healthy cattle and cattle that recovered from respiratory disease were examined for antibodies to IgA proteases. In order to assay the cleavage of bovine IgA with IgA1 protease, M. haemolytica culture supernatant was incubated with bovine IgA. Culture supernatant cleaved purified bovine IgA in the presence of ZnCl2. Both IgA proteases contain three domains, 1) IgA peptidase, 2) PL1_Passenger_AT and 3) autotransporter. IgA1 and IgA2 peptidases have molecular weights of 96.5 and 87 kDa, respectively. Convalescent bovine sera with naturally high anti-M. haemolytica antibody titers had high antibodies against all IgA1 & IgA2 protease components. Mouse immunizations indicated high antibodies to the IgA peptidases and autotransporters but not to PL1_Passenger_AT. These data indicate that M. haemolytica produces two IgA proteases that are immunogenic, can cleave bovine IgA, and are produced in vivo, as evidenced by antibodies in convalescent bovine sera. Further studies could focus on IgA protease importance in pathogenesis and immunity.


Assuntos
Antígenos de Bactérias/imunologia , Mannheimia haemolytica/enzimologia , Serina Endopeptidases/imunologia , Animais , Anticorpos Antibacterianos/sangue , Antígenos de Bactérias/genética , Bovinos , Clonagem Molecular , Ensaio de Imunoadsorção Enzimática , Imunoglobulina A/metabolismo , Mannheimia haemolytica/genética , Camundongos , Camundongos Endogâmicos BALB C , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Serina Endopeptidases/genética , Serina Endopeptidases/metabolismo
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