Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 7.759
Filtrar
1.
Nature ; 592(7852): 138-143, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33731925

RESUMO

A variety of species of bacteria are known to colonize human tumours1-11, proliferate within them and modulate immune function, which ultimately affects the survival of patients with cancer and their responses to treatment12-14. However, it is not known whether antigens derived from intracellular bacteria are presented by the human leukocyte antigen class I and II (HLA-I and HLA-II, respectively) molecules of tumour cells, or whether such antigens elicit a tumour-infiltrating T cell immune response. Here we used 16S rRNA gene sequencing and HLA peptidomics to identify a peptide repertoire derived from intracellular bacteria that was presented on HLA-I and HLA-II molecules in melanoma tumours. Our analysis of 17 melanoma metastases (derived from 9 patients) revealed 248 and 35 unique HLA-I and HLA-II peptides, respectively, that were derived from 41 species of bacteria. We identified recurrent bacterial peptides in tumours from different patients, as well as in different tumours from the same patient. Our study reveals that peptides derived from intracellular bacteria can be presented by tumour cells and elicit immune reactivity, and thus provides insight into a mechanism by which bacteria influence activation of the immune system and responses to therapy.


Assuntos
Antígenos de Bactérias/análise , Antígenos de Bactérias/imunologia , Bactérias/imunologia , Antígenos HLA/imunologia , Melanoma/imunologia , Melanoma/microbiologia , Peptídeos/análise , Peptídeos/imunologia , Apresentação do Antígeno , Bactérias/classificação , Bactérias/genética , Linhagem Celular Tumoral , Técnicas de Cocultura , Antígenos HLA/análise , Humanos , Linfócitos do Interstício Tumoral/citologia , Linfócitos do Interstício Tumoral/imunologia , Melanoma/patologia , Metástase Neoplásica/imunologia , Filogenia , RNA Ribossômico 16S/genética
2.
Aten. prim. (Barc., Ed. impr.) ; 52(9): 637-644, nov. 2020. graf, tab
Artigo em Inglês | IBECS | ID: ibc-198440

RESUMO

OBJECTIVE: This study was aimed at evaluating the appropriateness of use and interpretation of rapid antigen detection testing (RADT) and antibiotic prescribing for acute pharyngitis six years after a multifaceted intervention. DESIGN: Before-and-after audit-based study. LOCATION: Primary care centres in eight autonomous Communities. PARTICIPANTS: General practitioners (GP) who had participated in the HAPPY AUDIT intervention study in 2008 and 2009 were invited to participate in a third audit-based study six years later (2015). METHOD: RADTs were provided to the participating practices and the GPs were requested to consecutively register all adults with acute pharyngitis. A registration form specifically designed for this study was used. RESULTS: A total of 121 GPs out of the 210 who participated in the first two audits agreed to participate in the third audit (57.6%). They registered 3394 episodes of pharyngitis in the three registrations. RADTs were used in 51.7% of all the cases immediately after the intervention, and in 49.4% six years later. Antibiotics were prescribed in 21.3% and 36.1%, respectively (P < .001), mainly when tonsillar exudates were present, and in 5.3% and 19.2% of those with negative RADT results (P < .001). On adjustment for covariables, compared to the antibiotic prescription observed just after the intervention, significantly more antibiotics were prescribed six years later (odds ratio: 2.24, 95% confidence interval: 1.73-2.89). CONCLUSIONS: This study shows that that the long-term impact of a multifaceted intervention, focusing on the use and interpretation of RADT in patients with acute pharyngitis, is reducing


OBJETIVO: Evaluar la adecuación del uso e interpretación de las técnicas antigénicas rápidas (TAR) y la prescripción antibiótica en la faringitis aguda 6 años después de haber realizado una intervención multifacética. DISEÑO: Estudio antes-después basado en una auditoria. EMPLAZAMIENTO: Centros de salud en 8 comunidades autónomas. PARTICIPANTES: Se invitaron a médicos de familia (MF) que ya habían participado en el estudio de intervención HAPPY AUDIT en 2008 y 2009 a un nuevo AUDIT 6 años después (2015). MÉTODO: Se proporcionaron TAR a los centros participantes, y se pidió a los MF que registraran consecutivamente a todos los adultos con faringitis aguda. Usamos un registro diseñado específicamente para este estudio. RESULTADOS: Ciento veintiuno MF de los 210 que participaron en los primeros registros (57,6%) aceptaron a participar en el tercer registro. Se registraron 3.394 episodios de faringitis agudas en las 3 auditorías. Se usaron TAR en el 51,7% de los casos inmediatamente después de la intervención y en el 49,4%, 6 años después. Se prescribieron antibióticos en el 21,3%y 36,1%, respectivamente (p < 0,001), principalmente cuando había exudado amigdalar y en el 5,3 y 19,2% de los resultados de TAR negativos (p < 0,001). Después de ajustar por las distintas covariables, comparado con la prescripción antibiótica observada justo después de la intervención, prescribieron significativamente más antibióticos 6 años más tarde (odds ratio: 2,24 [IC 95%: 1,73-2,89]). CONCLUSIONES: Este estudio muestra que se reduce el impacto de una intervención multifacética a largo plazo enfocada al uso e interpretación de TAR en pacientes con faringitis aguda


Assuntos
Humanos , Masculino , Feminino , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Faringite/diagnóstico , Faringite/tratamento farmacológico , Testes Imediatos , Antibacterianos/uso terapêutico , Testes Imunológicos/métodos , Doença Aguda , Faringite/microbiologia , Antígenos de Bactérias/análise , Resultado do Tratamento , Fatores de Tempo
3.
Cochrane Database Syst Rev ; 6: CD013459, 2020 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-32597510

RESUMO

BACKGROUND: Plague is a severe disease associated with high mortality. Late diagnosis leads to advance stage of the disease with worse outcomes and higher risk of spread of the disease. A rapid diagnostic test (RDT) could help in establishing a prompt diagnosis of plague. This would improve patient care and help appropriate public health response. OBJECTIVES: To determine the diagnostic accuracy of the RDT based on the antigen F1 (F1RDT) for detecting plague in people with suspected disease. SEARCH METHODS: We searched the CENTRAL, Embase, Science Citation Index, Google Scholar, the World Health Organization International Clinical Trials Registry Platform and ClinicalTrials.gov up to 15 May 2019, and PubMed (MEDLINE) up to 27 August 2019, regardless of language, publication status, or publication date. We handsearched the reference lists of relevant papers and contacted researchers working in the field. SELECTION CRITERIA: We included cross-sectional studies that assessed the accuracy of the F1RDT for diagnosing plague, where participants were tested with both the F1RDT and at least one reference standard. The reference standards were bacterial isolation by culture, polymerase chain reaction (PCR), and paired serology (this is a four-fold difference in F1 antibody titres between two samples from acute and convalescent phases). DATA COLLECTION AND ANALYSIS: Two review authors independently selected studies and extracted data. We appraised the methodological quality of each selected studies and applicability by using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool. When meta-analysis was appropriate, we used the bivariate model to obtain pooled estimates of sensitivity and specificity. We stratified all analyses by the reference standard used and presented disaggregated data for forms of plague. We assessed the certainty of the evidence using GRADE. MAIN RESULTS: We included eight manuscripts reporting seven studies. Studies were conducted in three countries in Africa among adults and children with any form of plague. All studies except one assessed the F1RDT produced at the Institut Pasteur of Madagascar (F1RDT-IPM) and one study assessed a F1RDT produced by New Horizons (F1RDT-NH), utilized by the US Centers for Disease Control and Prevention. We could not pool the findings from the F1RDT-NH in meta-analyses due to a lack of raw data and a threshold of the test for positivity different from the F1RDT-IPM. Risk of bias was high for participant selection (retrospective studies, recruitment of participants not consecutive or random, unclear exclusion criteria), low or unclear for index test (blinding of F1RDT interpretation unknown), low for reference standards, and high or unclear for flow and timing (time of sample transportation was longer than seven days, which can lead to decreased viability of the pathogen and overgrowth of contaminating bacteria, with subsequent false-negative results and misclassification of the target condition). F1RDT for diagnosing all forms of plague F1RDT-IPM pooled sensitivity against culture was 100% (95% confidence interval (CI) 82 to 100; 4 studies, 1692 participants; very low certainty evidence) and pooled specificity was 70.3% (95% CI 65 to 75; 4 studies, 2004 participants; very low-certainty evidence). The performance of F1RDT-IPM against PCR was calculated from a single study in participants with bubonic plague (see below). There were limited data on the performance of F1RDT against paired serology. F1RDT for diagnosing pneumonic plague Performed in sputum, F1RDT-IPM pooled sensitivity against culture was 100% (95% CI 0 to 100; 2 studies, 56 participants; very low-certainty evidence) and pooled specificity was 71% (95% CI 59 to 80; 2 studies, 297 participants; very low-certainty evidence). There were limited data on the performance of F1RDT against PCR or against paired serology for diagnosing pneumonic plague. F1RDT for diagnosing bubonic plague Performed in bubo aspirate, F1RDT-IPM pooled sensitivity against culture was 100% (95% CI not calculable; 2 studies, 1454 participants; low-certainty evidence) and pooled specificity was 67% (95% CI 65 to 70; 2 studies, 1198 participants; very low-certainty evidence). Performed in bubo aspirate, F1RDT-IPM pooled sensitivity against PCR for the caf1 gene was 95% (95% CI 89 to 99; 1 study, 88 participants; very low-certainty evidence) and pooled specificity was 93% (95% CI 84 to 98; 1 study, 61 participants; very low-certainty evidence). There were no data providing data on both F1RDT and paired serology for diagnosing bubonic plague. AUTHORS' CONCLUSIONS: Against culture, the F1RDT appeared highly sensitive for diagnosing either pneumonic or bubonic plague, and can help detect plague in remote areas to assure management and enable a public health response. False positive results mean culture or PCR confirmation may be needed. F1RDT does not replace culture, which provides additional information on resistance to antibiotics and bacterial strains.


Assuntos
Antígenos de Bactérias/análise , Peste/diagnóstico , Yersinia pestis/imunologia , Adulto , Criança , Intervalos de Confiança , Estudos Transversais , Reações Falso-Negativas , Reações Falso-Positivas , Humanos , Peste/imunologia , Sensibilidade e Especificidade , Fatores de Tempo
4.
Int J Infect Dis ; 97: 190-196, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32497795

RESUMO

BACKGROUND: Discriminating active tuberculosis (ATB) from latent tuberculosis infection (LTBI) remains challenging. This study aimed to investigate a diagnostic model based on a combination of iron metabolism and the TB-specific antigen/phytohemagglutinin ratio (TBAg/PHA ratio) in T-SPOT.TB assay for differentiation between ATB and LTBI. METHODS: A total of 345 participants with ATB (n=191) and LTBI (n=154) were recruited based on positive T-SPOT.TB results at Tongji hospital between January 2017 and January 2020. Iron metabolism analysis was performed simultaneously. A diagnostic model for distinguishing ATB from LTBI was established according to multivariate logistic regression. RESULTS: The TBAg/PHA ratio showed 64.00% sensitivity and 90.10% specificity in distinguishing ATB from LTBI when a threshold of 0.22 was used. All iron metabolism biomarkers in the ATB group were significantly different from those in the LTBI group. Specifically, serum ferritin and soluble transferrin receptor in ATB were significantly higher than LTBI. On the contrary, serum iron, transferrin, total iron binding capacity, and unsaturated iron binding capacity in ATB were significantly lower than LTBI. The combination of iron metabolism indicators accurately predicted 60.00% of ATB cases and 91.09% of LTBI subjects, respectively. Moreover, the combination of iron metabolism indexes and TBAg/PHA ratio resulted in a sensitivity of 88.80% and specificity of 90.10%. Furthermore, the performance of models established in the Qiaokou cohort was confirmed in the Caidian cohort. CONCLUSIONS: The data suggest that the combination of iron metabolism indexes and TBAg/PHA ratio could serve as a biomarker to distinguish ATB from LTBI in T-SPOT-positive individuals.


Assuntos
Antígenos de Bactérias/análise , Técnicas e Procedimentos Diagnósticos , Ferro/sangue , Tuberculose Latente/diagnóstico , Fito-Hemaglutininas/sangue , Tuberculose/diagnóstico , Adulto , Biomarcadores/sangue , Estudos de Coortes , Análise Discriminante , Feminino , Humanos , Tuberculose Latente/sangue , Tuberculose Latente/microbiologia , Masculino , Pessoa de Meia-Idade , Mycobacterium tuberculosis , Sensibilidade e Especificidade , Tuberculose/sangue , Tuberculose/microbiologia
5.
Int J Infect Dis ; 96: 244-253, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32353548

RESUMO

OBJECTIVES: This study examined Mycobacterium tuberculosis (MTB)-secreted MPT64 as a surrogate of bacterial viability for the diagnosis of active pulmonary TB (PTB) and for follow-up treatment. METHODS: In this proof-of-concept prospective study, 50 PTB patients in the Tokyo metropolitan region, between 2017 and 2018, were consecutively included and 30 healthy individuals were also included. Each PTB patient submitted sputum on days 0, 14 and 28 for diagnosis and follow-up, and each healthy individual submitted one sputum sample. The following were performed: smear microscopy, Xpert MTB/RIF, MGIT and solid culture, and MPT64 detection on the sputum samples. Ultrasensitive ELISA (usELISA) was used to detect MPT64. The receiver operating characteristic analyses for diagnosis and follow-up revealed the optimal cut-off value of MPT64 absorbance for detecting culture positivity at multiple intervals. RESULTS: The sensitivity of MPT64 for diagnosing PTB was 88.0% (95% CI 75.7-95.5) and the specificity was 96.7% (95% CI 82.8-99.9). The specificity of MPT64 for predicting negative culture results on day 14 was 89.5% (95% CI 66.9-98.7). The sensitivity of MPT64 for predicting positive culture results on day 28 was 81.0% (95% CI 58.1-94.6). CONCLUSIONS: This study revealed that MPT64 is useful for diagnosing active PTB in patients and predicting treatment efficacy at follow-up.


Assuntos
Antígenos de Bactérias/análise , Ensaio de Imunoadsorção Enzimática/métodos , Mycobacterium tuberculosis/isolamento & purificação , Escarro/microbiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Microscopia/métodos , Pessoa de Meia-Idade , Mycobacterium tuberculosis/fisiologia , Estudos Prospectivos , Sensibilidade e Especificidade , Tóquio , Tuberculose Pulmonar/diagnóstico
6.
Am J Clin Pathol ; 154(2): 255-265, 2020 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-32445464

RESUMO

OBJECTIVES: To assess the concordance and performance characteristics of Helicobacter pylori laboratory tests compared with histopathology and to propose algorithms for the diagnosis of H pylori that minimize diagnostic error. METHODS: H pylori diagnostics were reviewed from a 12-year period within a health system (2,560 cases). Analyses were performed to adjust diagnostic performance based on treatment and consensus histopathologic diagnoses among pathologists. Markers of access to care, including test cancellation frequency and turnaround time, were assessed. Costs and performance of candidate noninvasive testing algorithms were modeled as a function of disease prevalence. RESULTS: Serum H pylori IgG demonstrated a higher sensitivity (0.94) than urea breath and stool antigen tests (0.64 and 0.61, respectively). Evidence of an advantage in access to care for serology included a lower cancellation rate. Interobserver variability was higher (κ = 0.34) among pathologists for cases with a discordant laboratory test than concordant cases (κ = 0.56). A model testing algorithm utilizing serology for first-time diagnoses minimizes diagnostic error. CONCLUSIONS: Although H pylori serology has modestly lower specificity than other noninvasive tests, the superior sensitivity and negative predictive value in our population support its use as a noninvasive test to rule out H pylori infection. Reflexive testing with positive serology followed by either stool antigen or urea breath test may optimize diagnostic accuracy in low-prevalence populations.


Assuntos
Gastrite/diagnóstico , Infecções por Helicobacter/diagnóstico , Helicobacter pylori/isolamento & purificação , Adulto , Antígenos de Bactérias/análise , Testes Respiratórios , Feminino , Gastrite/sangue , Gastrite/microbiologia , Infecções por Helicobacter/sangue , Infecções por Helicobacter/microbiologia , Humanos , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Testes Sorológicos , Ureia/análise
7.
Am J Clin Pathol ; 153(5): 686-694, 2020 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-32145011

RESUMO

OBJECTIVES: Helicobacter pylori stool antigen test (HpSAT) appropriateness was investigated by assessing its testing and positivity rates in Calgary, Canada. METHODS: The laboratory information system was accessed for all patients who received an HpSAT in 2018. Testing volume, test results, age, and sex of patients were collected. Sociodemographic risk factors and geospatial analysis were performed by matching laboratory data to the 2016 census data. Testing appropriateness was defined as a concordance between testing and positivity rates for each sociodemographic variable. RESULTS: In 2018, 25,518 H pylori stool antigen tests were performed in Calgary, with an overall positivity rate of 14.7%. Geospatial mapping demonstrated significant distribution variations of testing and positivity rates of HpSAT in the city. Certain sociodemographic groups studied (eg, recent immigrants) appeared to be appropriately tested (testing rate relative risk [RR] = 2.26, positivity rate RR = 4.32; P < .0001), while other groups (eg, male) may have been undertested (testing rate RR = 0.85, positivity rate RR = 1.14; P < .0001). CONCLUSIONS: Determining concordance of testing and positivity rate of a laboratory test can be used for assessing testing appropriateness for other diseases in other jurisdictions. This study demonstrated some at-risk patients may be missed for H pylori testing.


Assuntos
Antígenos de Bactérias/análise , Infecções por Helicobacter/diagnóstico , Helicobacter pylori/imunologia , Adolescente , Adulto , Idoso , Canadá , Criança , Pré-Escolar , Feminino , Infecções por Helicobacter/imunologia , Humanos , Técnicas Imunoenzimáticas , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Adulto Jovem
8.
Dig Dis Sci ; 65(7): 1917-1931, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32170476

RESUMO

As one of the most prevalent infections globally, Helicobacter pylori (H. pylori) continues to present diagnostic and therapeutic challenges for clinicians worldwide. Diagnostically, the "test-and-treat" strategy is the recommended approach for healthcare practitioners when managing this potentially curable disease. The choice of testing method should be based on several factors including patient age, presenting symptoms, and medication use, as well as test reliability, availability, and cost. With rising antibiotic resistance, particularly of macrolides, care must be taken to ensure that therapy is selected based on regional resistance patterns and prior antibiotic exposure. In the USA, macrolide antibiotic resistance rates in some areas have reached or exceeded a generally accepted threshold, such that clarithromycin triple therapy may no longer be an appropriate first-line empiric treatment. Instead, bismuth quadruple therapy should be considered, while levofloxacin-based or alternative macrolide-containing therapies are also options. Once treated, it is essential to test for eradication as untreated H. pylori is associated with serious complications including peptic ulcer disease, mucosa-associated lymphoid tissue lymphoma, and gastric cancer. This review article aims to consolidate current knowledge of H. pylori infection with a particular emphasis on diagnostic and treatment strategies.


Assuntos
Antibacterianos/uso terapêutico , Antiulcerosos/uso terapêutico , Infecções por Helicobacter/tratamento farmacológico , Inibidores da Bomba de Prótons/uso terapêutico , Amoxicilina/uso terapêutico , Antígenos de Bactérias/análise , Biópsia , Bismuto/uso terapêutico , Testes Respiratórios , Claritromicina/uso terapêutico , Técnicas de Cultura , Doxiciclina/uso terapêutico , Farmacorresistência Bacteriana , Quimioterapia Combinada , Dispepsia/etiologia , Fezes/química , Gastroscopia , Infecções por Helicobacter/complicações , Infecções por Helicobacter/diagnóstico , Helicobacter pylori , Humanos , Levofloxacino/uso terapêutico , Linfoma de Zona Marginal Tipo Células B/etiologia , Metronidazol/uso terapêutico , Compostos Organometálicos/uso terapêutico , Úlcera Péptica/etiologia , Reação em Cadeia da Polimerase , Rifabutina/uso terapêutico , Salicilatos/uso terapêutico , Terapia de Salvação , Testes Sorológicos , Neoplasias Gástricas/etiologia , Tetraciclina/uso terapêutico , Tiazóis/uso terapêutico , Resultado do Tratamento , Ureia/metabolismo
9.
Int J Infect Dis ; 91: 182-187, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31770617

RESUMO

BACKGROUND: Whether T-cell interferon-γ responses to Mycobacterium tuberculosis-specific antigens can be influenced by tuberculosis preventive treatment in a high-endemic country is uncertain. METHODS: In this prospective, open-label, controlled study, 513 individuals with silicosis were randomly selected for TB preventive treatment with rifapentine and isoniazid or for observation. QuantiFERON-TB Gold in-tube (QFT-GIT) assay was used to measure IFN-γ response to M. tuberculosis antigens at baseline (T0) and at 6 (T1) and 33 (T2) months after completion of therapy. RESULTS: A total of 220 subjects were included in the final analysis: 105 and 115 in the prevention and observation arms, respectively. The proportions of QFT-GIT reversion from baseline to T1 were similar in the prevention and observation arms (18.4% vs 12.8%, P=0.566). However, reversion from baseline to T2 was more frequent in the prevention arm than in the observation arm, but the difference was not significant (24.2% vs 6.3%, P=0.881). No significant difference was observed in the quantitative responses of QFT-GIT between the two arms during follow-up at T1 (P=0.648) and T2 (P=0.918). CONCLUSIONS: Preventive tuberculosis treatment has no effect on interferon-γ responses measured by serial QFT-GIT assays in a high tuberculosis-endemic country. CLINICAL TRIALS REGISTRATION: http://www.clinicaltrials.gov NCT02430259.


Assuntos
Antituberculosos/uso terapêutico , Interferon gama/sangue , Tuberculose/prevenção & controle , Antígenos de Bactérias/análise , Antígenos de Bactérias/imunologia , China/epidemiologia , Testes Diagnósticos de Rotina , Doenças Endêmicas/prevenção & controle , Doenças Endêmicas/estatística & dados numéricos , Feminino , Seguimentos , Humanos , Testes de Liberação de Interferon-gama , Isoniazida/uso terapêutico , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Rifampina/análogos & derivados , Rifampina/uso terapêutico , Teste Tuberculínico , Tuberculose/sangue , Tuberculose/epidemiologia , Tuberculose/microbiologia
10.
J Fish Dis ; 43(1): 81-89, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31701546

RESUMO

Mycobacteriosis in cultured fish is a challenge for the aquaculture industry worldwide. Treatment by chemical administration is difficult and no effective vaccine has been developed. Therefore, detection and isolation by early diagnosis are important for prevention of the spread of the disease. In mammals, interferon gamma release assays have been established for detection of tuberculosis; these tests are based on the delayed-type hypersensitivity (DTH) response against culture filtrate protein-10 (CFP-10) and the 6-kDa early secreted antigen target (ESAT-6) of Mycobacterium tuberculosis. On the other hand, little is known about the fish immune response against the ESAT-6 and CFP-10 proteins of mycobacteria, although these responses should find application in the diagnosis of mycobacteriosis in fish. In the present study, we identified ESAT-6 and CFP-10 from Mycobacterium pseudoshottsii and cloned the corresponding genes. Intraperitoneal injection of the corresponding DNA plasmid constructs in ginbuna crucian carp yielded increased expression of the fish interferon-γ1-1-encoding gene (IFN-γ1-1). In contrast, IFN-γ1-1 expression accompanied by DTH response was observed only in the CFP-10-DNA plasmid-injected fish. Furthermore, fish that had been prophylactically injected with CFP-10-DNA plasmid exhibited increased survival of M. pseudoshottsii infection. Taken together, these results suggested that CFP-10 may facilitate diagnosis of mycobacteriosis.


Assuntos
Antígenos de Bactérias/análise , Proteínas de Bactérias/análise , Doenças dos Peixes/diagnóstico , Carpa Dourada , Infecções por Mycobacterium/veterinária , Mycobacterium/fisiologia , Sequência de Aminoácidos , Animais , Antígenos de Bactérias/química , Antígenos de Bactérias/genética , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Doenças dos Peixes/microbiologia , Mycobacterium/química , Mycobacterium/genética , Infecções por Mycobacterium/diagnóstico , Infecções por Mycobacterium/microbiologia , Filogenia , Alinhamento de Sequência
11.
Clin Rheumatol ; 39(2): 463-469, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31713731

RESUMO

OBJECTIVE: The aim of this study was to determine the frequency of Helicobacter pylori in SLE patients and to compare clinical characteristics and gastroduodenal lesions in patients with and without H. pylori infection. METHODS: Adult SLE patients were selected and subjected to endoscopy. Gastroduodenal lesions were examined by endoscopy and biopsy (antrum and corpus). Biopsies were evaluated by hematoxylin and eosin and Giemsa staining. Immunochromatographic membrane-based assay using amplification was used to test for H. pylori antigen (coproantigen) in stool samples in all participants. Clinical characteristics and gastroduodenal lesions were compared between patients with and without H. pylori infection. RESULTS: A total of 118 SLE patients were included (mean age 44.7 ± 11.7 years, mean disease duration 11.6 ± 6.0 years), of whom 101 (85.6%) were receiving non-steroidal anti-inflammatory drugs (NSAIDs). The coproantigen test was positive in 32 (27.1%) patients. H. pylori was present in twenty six patients (22.0%) in the gastric biopsy. The frequency of gastric erosions and gastric ulcers were 55.1% and 0.8%, respectively. Gastric erosions were less frequent in SLE patients with H. pylori infection than those without H. pylori (43.5.7% vs. 62.5%; p = 0.04). The age, disease duration, disease activity, chronic damage, gastroprotective drugs, and immunosuppressive therapy did not differ between the two groups. CONCLUSIONS: We found a high frequency of H. pylori infection in SLE patients. The severity of SLE and reception of gastroprotective therapy do not seem to be related to H. pylori infection. Immunosuppressive therapy may not be protective against H. pylori infection in SLE patients.Key Points• In patients with systemic lupus erythematosus (SLE), the frequency of Helicobacter pylori infection was 39% and gastric erosions were frequent.• Disease activity, chronic damage, gastroprotective drugs, and immunosuppressive therapy may not affect the prevalence of H. pylori infection in SLE patients.


Assuntos
Duodenite/epidemiologia , Gastrite/epidemiologia , Infecções por Helicobacter/epidemiologia , Lúpus Eritematoso Sistêmico/epidemiologia , Úlcera Gástrica/epidemiologia , Adulto , Anti-Inflamatórios não Esteroides/uso terapêutico , Antígenos de Bactérias/análise , Biópsia , Estudos de Casos e Controles , Duodenite/patologia , Endoscopia do Sistema Digestório , Fezes/química , Feminino , Gastrite/patologia , Helicobacter pylori , Humanos , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Gastropatias/epidemiologia , Gastropatias/patologia , Úlcera Gástrica/patologia
12.
BMC Infect Dis ; 19(1): 1023, 2019 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-31791276

RESUMO

BACKGROUND: Staphylococcus aureus carriage is a known risk factor for staphylococcal disease. However, the carriage rates vary by country, demographic group and profession. This study aimed to determine the S. aureus carriage rate in children in Eastern Uganda, and identify S. aureus lineages that cause infection in Uganda. METHODS: Nasopharyngeal samples from 742 healthy children less than 5 years residing in the Iganga/Mayuge Health and Demographic Surveillance Site in Eastern Uganda were processed for isolation of S. aureus. Antibiotic susceptibility testing based on minimum inhibitory concentrations (MICs) was determined by the BD Phoenix™ system. Genotyping was performed by spa and SCCmec typing. RESULTS: The processed samples yielded 144 S. aureus isolates (one per child) therefore, the S. aureus carriage rate in children was 19.4% (144/742). Thirty one percent (45/144) of the isolates were methicillin resistant (MRSA) yielding a carriage rate of 6.1% (45/742). All isolates were susceptible to rifampicin, vancomycin and linezolid. Moreover, all MRSA were susceptible to vancomycin, linezolid and clindamycin. Compared to methicillin susceptible S. aureus (MSSA) isolates (68.8%, 99/144), MRSA isolates were more resistant to non-beta-lactam antimicrobials -trimethoprim/sulfamethoxazole 73.3% (33/45) vs. 27.3% (27/99) [p < 0.0001]; erythromycin 75.6% (34/45) vs. 24.2% (24/99) [p < 0.0001]; chloramphenicol 60% (27/45) vs. 19.2% (19/99) [p < 0.0001]; gentamicin 55.6% (25/45) vs. 25.3% (25/99) [p = 0.0004]; and ciprofloxacin 35.6% (16/45) vs. 2% (2/99) [p < 0.0001]. Furthermore, 42 MRSA (93.3%) were multidrug resistant (MDR) and one exhibited high-level resistance to mupirocin. Overall, 61 MSSA (61.6%) were MDR, including three mupirocin and clindamycin resistant isolates. Seven spa types were detected among MRSA, of which t037 and t064 were predominant and associated with SCCmec types I and IV, respectively. Fourteen spa types were detected in MSSA which consisted mainly of t645 and t4353. CONCLUSIONS: S. aureus carriage rate in healthy children in Eastern Uganda is high and comparable to rates for hospitalized patients in Kampala. The detection of mupirocin resistance is worrying as it could rapidly increase if mupirocin is administered in a low-income setting. S. aureus strains of spa types t064, t037 (MRSA) and t645, t4353 (MSSA) are prevalent and could be responsible for majority of staphylococcal infections in Uganda.


Assuntos
Antígenos de Bactérias/análise , Portador Sadio/epidemiologia , Farmacorresistência Bacteriana , Nariz/microbiologia , Faringe/microbiologia , Infecções Estafilocócicas/epidemiologia , Staphylococcus aureus/isolamento & purificação , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Antígenos de Bactérias/classificação , Antígenos de Bactérias/genética , Portador Sadio/microbiologia , Pré-Escolar , Estudos Transversais , Farmacorresistência Bacteriana/genética , Feminino , Técnicas de Genotipagem/métodos , Humanos , Lactente , Recém-Nascido , Masculino , Staphylococcus aureus Resistente à Meticilina/genética , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Testes de Sensibilidade Microbiana , Tipagem Molecular/métodos , Mupirocina/farmacologia , Mupirocina/uso terapêutico , Mucosa Nasal/microbiologia , Vigilância da População/métodos , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/classificação , Staphylococcus aureus/genética , Uganda/epidemiologia
13.
Int. microbiol ; 22(4): 471-478, dic. 2019. graf, tab
Artigo em Inglês | IBECS | ID: ibc-185065

RESUMO

Chlamydia trachomatis is considered as a public health problem due to its high prevalence and increased rates of gynecological disorders. The major outer membrane protein (MOMP) of this bacterium is the most abundant protein in its membrane and has been evaluated not only as a vaccine development candidate but also is used in many diagnostic tests. The MOMP weighs 69 kDa and contains four variable segments (VS 1-4) separated by constant regions. Several research groups have developed recombinant single-variable segments of MOMP expressed in Escherichia coli cytoplasm. But, all variable segments have been used minimally for the diagnosis of a chlamydial infection. In this experiment, the authors obtained the recombinant MOMP of C. trachomatis (rMOMP) in E. coli rMOMP and extracted, purified, and partially characterized it. This was later used to identify anti-Chlamydia trachomatis antibodies in sera of infertile patients by immunodetection assays, enzyme-linked immunosorbent assay (ELISA), and indirect immunofluorescence tests. The ELISA test showed high sensitivity and low specificity of 100 and 58.3%, respectively. The above results obtained were linked to the cross-reactivity of antibodies against C. pneumoniae or C. psittaci. Hence, an evaluation was performed to obtain an optimized test for the diagnosis of C. trachomatis infection


No disponible


Assuntos
Antígenos de Bactérias/análise , Chlamydia trachomatis/isolamento & purificação , Infecções por Chlamydia/diagnóstico , Ensaio de Imunoadsorção Enzimática/métodos , Proteínas Recombinantes/análise , Proteínas da Membrana Bacteriana Externa/metabolismo , Chlamydia trachomatis/genética , Infecções por Chlamydia/microbiologia , Proteínas Recombinantes/genética
14.
PLoS Negl Trop Dis ; 13(11): e0007825, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31756188

RESUMO

BACKGROUND: Enterotoxigenic Escherichia coli (ETEC) cause significant diarrheal morbidity and mortality in children of resource-limited regions, warranting development of effective vaccine strategies. Genetic diversity of the ETEC pathovar has impeded development of broadly protective vaccines centered on the classical canonical antigens, the colonization factors and heat-labile toxin. Two non-canonical ETEC antigens, the EtpA adhesin, and the EatA mucinase are immunogenic in humans and protective in animal models. To foster rational vaccine design that complements existing strategies, we examined the distribution and molecular conservation of these antigens in a diverse population of ETEC isolates. METHODS: Geographically diverse ETEC isolates (n = 1159) were interrogated by PCR, immunoblotting, and/or whole genome sequencing (n = 46) to examine antigen conservation. The most divergent proteins were purified and their core functions assessed in vitro. RESULTS: EatA and EtpA or their coding sequences were present in 57.0% and 51.5% of the ETEC isolates overall, respectively; and were globally dispersed without significant regional differences in antigen distribution. These antigens also exhibited >93% amino acid sequence identity with even the most divergent proteins retaining the core adhesin and mucinase activity assigned to the prototype molecules. CONCLUSIONS: EtpA and EatA are well-conserved molecules in the ETEC pathovar, suggesting that they serve important roles in virulence and that they could be exploited for rational vaccine design.


Assuntos
Antígenos de Bactérias/genética , Escherichia coli Enterotoxigênica/genética , Infecções por Escherichia coli/microbiologia , Proteínas de Escherichia coli/genética , Variação Genética , Glicoproteínas de Membrana/genética , Peptídeo Hidrolases/genética , Antígenos de Bactérias/análise , Escherichia coli Enterotoxigênica/química , Escherichia coli Enterotoxigênica/classificação , Escherichia coli Enterotoxigênica/isolamento & purificação , Infecções por Escherichia coli/imunologia , Proteínas de Escherichia coli/análise , Saúde Global , Humanos , Immunoblotting , Glicoproteínas de Membrana/análise , Peptídeo Hidrolases/análise , Reação em Cadeia da Polimerase , Sequenciamento Completo do Genoma
15.
Rev. méd. Chile ; 147(11): 1382-1389, nov. 2019. tab, graf
Artigo em Espanhol | LILACS | ID: biblio-1094167

RESUMO

Background Chile has one of the highest mortality rates by gastric cancer (GC) worldwide. Primary prevention of GC and detection of pre-neoplastic and early neoplastic lesions should be a national priority. Aim To assess the impact of the protocolization of endoscopy referral and the use of H. pylori stool antigen test (HPSA) in the management of dyspepsia to decrease the waiting list for endoscopy and increase the detection of gastric pre-neoplastic and early neoplastic lesions. Material and Methods We included all patients referred to the Endoscopy Unit of a regional hospital, from January 2015 to December 2017. We also included patients with known pre-neoplastic lesions and all those with first degree relatives with GC. We implemented protocols for referral of patients with dyspepsia considering the use of HPSA test, prioritizing to endoscopy those with a higher risk of GC. Results A total of 4,641 endoscopies and 2,631 HPSA tests were carried out. After the adoption of these protocols, we observed a 52% decrease in the waiting time for endoscopy. The GC detection rate in this period was 1.8 to 3.1 cases per 100 endoscopies. After the adoption of the protocols, we observed a significant increase in early GC detection rate (from none in 2015 to 13% in 2017, p = 0.03). Conclusions The protocolization of the referral for endoscopy associated with widespread use of HPSA test in the management of patients with dyspepsia, are successful strategies to decrease waiting lists for endoscopy and optimize the detection rate of pre-neoplastic lesions and early GC.


Assuntos
Humanos , Lesões Pré-Cancerosas/diagnóstico , Listas de Espera , Helicobacter pylori/isolamento & purificação , Infecções por Helicobacter/diagnóstico , Dispepsia/diagnóstico , Fezes/microbiologia , Antígenos de Bactérias/análise , Lesões Pré-Cancerosas/microbiologia , Atenção Primária à Saúde , Encaminhamento e Consulta , Infecções por Helicobacter/complicações , Infecções por Helicobacter/microbiologia , Sensibilidade e Especificidade , Diagnóstico Precoce , Dispepsia/microbiologia , Endoscopia/estatística & dados numéricos
16.
PLoS One ; 14(9): e0221903, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31479482

RESUMO

Bacterial leaf scorch, caused by Xylella fastidiosa, is a major threat to blueberry production in the southeastern United States. Management of this devastating disease is challenging and often requires early detection of the pathogen to reduce major loss. There are several different molecular and serological detection methods available to identify the pathogen. Knowing the efficiency and suitability of these detection techniques for application in both field and laboratory conditions is important when selecting the appropriate detection tool. Here, we compared the efficiency and the functionality of four different molecular detection techniques (PCR, real-time PCR, LAMP and AmplifyRP® Acceler8™) and one serological detection technique (DAS-ELISA). The most sensitive method was found to be real-time PCR with the detection limit of 25 fg of DNA molecules per reaction (≈9 genome copies), followed by LAMP at 250 fg per reaction (≈90 copies), AmplifyRP® Acceler8™ at 1 pg per reaction (≈350 copies), conventional PCR with nearly 1.25 pg per reaction (≈ 440 copies) and DAS-ELISA with 1x105 cfu/mL of Xylella fastidiosa. Validation between assays with 10 experimental samples gave consistent results beyond the variation of the detection limit. Considering robustness, portability, and cost, LAMP and AmplifyRP® Acceler8™ were not only the fastest methods but also portable to the field and didn't require any skilled labor to carry out. Among those two, AmplifyRP® Acceler8™ was faster but more expensive and less sensitive than LAMP. On the other hand, real-time PCR was the most sensitive assay and required comparatively lesser time than C-PCR and DAS-ELISA, which were the least sensitive assays in this study, but all three assays are not portable and needed skilled labor to proceed. These findings should enable growers, agents, and diagnosticians to make informed decisions regarding the selection of an appropriate diagnostic tool for X. fastidiosa on blueberry.


Assuntos
Mirtilos Azuis (Planta)/microbiologia , Doenças das Plantas/microbiologia , Xylella/genética , Xylella/imunologia , Anticorpos Antibacterianos , Antígenos de Bactérias/análise , Técnicas Bacteriológicas/métodos , DNA Bacteriano/análise , DNA Bacteriano/genética , Ensaio de Imunoadsorção Enzimática/métodos , Técnicas Genéticas , Limite de Detecção , Técnicas de Amplificação de Ácido Nucleico/métodos , Reação em Cadeia da Polimerase/métodos , Reação em Cadeia da Polimerase em Tempo Real/métodos , Xylella/isolamento & purificação
17.
BMC Infect Dis ; 19(1): 796, 2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31510926

RESUMO

BACKGROUND: The number of new rickettsial species are rapidly increasing, and increasing numbers of Rickettsia raoultii (R. raoultii) infection cases have been detected in humans. However, neurological abnormalities caused by R. raoultii are rarely reported, especially in northwestern China. CASE PRESENTATION: A 36-year-old Kazakh shepherd with an attached tick on part temporalis, presented with right eyelid droop, lethargy, fever, headache, fever (38.0-41.0 °C) and erythematous rash. The examination of cerebrospinal fluid (CSF) showed cerebrospinal pressure of 200 mm H2O, leukocyte count of 300.0 × 106/L, adenosine deaminase of 2.15 U/L, and total protein concentration of 0.93 g/L. The diagnosis of R. raoultii infection was confirmed by six genetic markers, and semi-quantified by enzyme-linked immunosorbent assay for rickettsial antigen. The patient gradually recovered after treatment with doxycycline and ceftriaxone. R. raoultii DNA was found both in a tick detached from this patient and in 0.18% (2/1107) of blood samples collected from local shepherds. CONCLUSIONS: This is the first reported case with neurological abnormalities caused by R. raoultii in northwestern China. It is vital to detect rickettsial agents both in blood and CSF for tick bite patients with neurological abnormalities. Public health workers and physicians should pay attention to neurological abnormalities caused by Rickettsia.


Assuntos
Doenças do Sistema Nervoso/diagnóstico , Infecções por Rickettsia/diagnóstico , Rickettsia/metabolismo , Picadas de Carrapatos/diagnóstico , Adenosina Desaminase/líquido cefalorraquidiano , Adulto , Animais , Antígenos de Bactérias/análise , Antígenos de Bactérias/imunologia , Ceftriaxona/uso terapêutico , China , DNA Bacteriano/sangue , Doxiciclina/uso terapêutico , Humanos , Contagem de Leucócitos , Masculino , Doenças do Sistema Nervoso/etiologia , Filogenia , RNA Ribossômico 16S/metabolismo , Rickettsia/classificação , Rickettsia/genética , Infecções por Rickettsia/complicações , Infecções por Rickettsia/tratamento farmacológico , Picadas de Carrapatos/complicações , Carrapatos/genética
18.
Int J Biol Macromol ; 140: 842-850, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31470050

RESUMO

Bacillus anthracis, the causative agent of anthrax, is a harmful pathogen with potential ability as a biological weapon which persuades scientists to develop novel methods to detect anthrax from infected resources. In this study, a multi-walled carbon nanotube (MWCNTs)-based fluorescence aptasensor was fabricated to detect the recombinant protective antigen domain 4 (rPAD4) of Bacillus anthracis as the most important key factor in development of anthrax. First, PAD4 was recombinant expressed in E. coli and purified by Ni-NTA column. Second, the affinity of aptamer to rPAD4 was confirmed by ELAA assay. In aptasensor design, the aptamer was labeled with Gel Green and immobilized on MWCNTs. Upon the adsorption of labeled aptamer on MWCNTs, fluorescence emission was quenched. In contrast, by adding rPAD4 to hybridization reaction and incubation for 10 min, the fluorescence emission was significantly recovered to 85% compared to the control. Detection limit for the sensitivity and specificity of the aptasensor was determined 20 ng/ml and 62.5 ng/ml purified and unpurified rPAD4 protein, respectively. Also, applicability of aptasensor was showed in mouse serum sample. Finally, results indicated that nanosensor has the potential to be developed as a high-sensitive, cost-effective and fast-acting system for measuring of PA in anthrax diagnostic tests.


Assuntos
Antígenos de Bactérias/análise , Aptâmeros de Nucleotídeos , Toxinas Bacterianas/análise , Técnicas Biossensoriais , DNA de Cadeia Simples/química , Fluorescência , Nanotubos de Carbono/química , Nanotubos de Carbono/ultraestrutura , Proteínas Recombinantes de Fusão
19.
Tuberculosis (Edinb) ; 118: 101852, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31430697

RESUMO

Tuberculosis (TB), a life threatening communicable disease, is mainly caused by the bacterium named Mycobacterium tuberculosis (MTB). This high burden infectious threat is the ninth leading killer disease worldwide and also the foremost cause of death from a single infectious agent, even ranking above HIV/AIDS. In this work, a novel magnetic biosensing technique based on giant magneto-resistance (GMR) has been proposed for the on-field detection of Tuberculosis (TB) through assessment of MTB specific protein- ESAT-6. This portable highly sensitive diagnostic tool provides the results with a low turnaround time and the achieved limit of detection in the range of pg/ml can be a breakthrough in TB diagnostics. In addition, the use of DARPins (designed ankyrin repeat proteins) leads to high specificity and help in early detection, thus enabling early onset of treatment and thereby reduced mortality. This study compares the results of conventional and GNP-ELISA and it has been shown that the proposed GMR technique is more sensitive. Further, the effect of different sized magnetic nanoparticles on the performance of GMR biosensor is also presented.


Assuntos
Antígenos de Bactérias/análise , Proteínas de Bactérias/análise , Técnicas Biossensoriais/métodos , Tuberculose/diagnóstico , Repetição de Anquirina , Diagnóstico Precoce , Ensaio de Imunoadsorção Enzimática/métodos , Humanos , Limite de Detecção , Campos Magnéticos , Nanopartículas de Magnetita
20.
Braz J Microbiol ; 50(4): 979-984, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31352634

RESUMO

Control of brucellosis as a worldwide zoonotic disease is based on vaccination of animals and diagnosis of infected cases to be eradicated. Accurate and rapid detection of infected animals is of critical importance for preventing the spread of disease. Current detection of brucellosis is based on whole-cell antigens and investigating serum antibodies against Brucella lipopolysaccharide (LPS). The critical disadvantage is misdiagnosis of vaccinated animals as infected ones and also cross-reactions with other Gram-negative bacteria. Recombinant outer membrane protein 2b (Omp2b) of Brucella abortus was evaluated as a novel serodiagnostic target in comparison to conventional tests which are based on LPS. Recombinant Omp2b (rOmp2b) was expressed in Escherichia coli BL21 and purified by Ni2+-based chromatography. rOmp2b was evaluated in an indirect enzyme-linked immunosorbent assay (ELISA) system for diagnosis of brucellosis, with sera from Brucella-infected mice along with negative sera and sera from mice which were inoculated with other Gram-negative species for assurance of specificity. Thereafter, cattle sera collected from different regions were assessed along with known negative and known positive serum samples. We found that Omp2b can discriminate between Brucella-infected animals and non-infected ones. Results for assessment of two hundred and fifty cattle sera by Omp2b-based indirect ELISA which were compared to Rose Bengal plate agglutination test (RBPT) and serum tube agglutination test (SAT) showed that our proposed procedure has the sensitivity of 88.5%, specificity of 100%, and accuracy of 90.8%. We suggest that recombinant Omp2b could be used as a protein antigen for diagnosis of brucellosis in domestic animals and can be evaluated for detection of human brucellosis.


Assuntos
Antígenos de Bactérias/análise , Proteínas de Bactérias/análise , Brucella abortus/isolamento & purificação , Brucelose/veterinária , Doenças dos Bovinos/diagnóstico , Ensaio de Imunoadsorção Enzimática/métodos , Porinas/análise , Testes Sorológicos/métodos , Animais , Antígenos de Bactérias/genética , Antígenos de Bactérias/imunologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/imunologia , Brucella abortus/genética , Brucella abortus/imunologia , Brucelose/diagnóstico , Brucelose/microbiologia , Bovinos , Doenças dos Bovinos/microbiologia , Feminino , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Porinas/genética , Porinas/imunologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...