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1.
BMC Infect Dis ; 21(1): 513, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-34074248

RESUMO

BACKGROUND: In resource-limited settings, sputum smear conversion is used to document treatment response. Many People living with HIV (PLHIV) are smear-negative at baseline. The Xpert MTB/RIF test can indirectly measure bacterial load through cycle threshold (ct) values. This study aimed to determine if baseline Xpert MTB/RIF could predict time to culture negativity in PLHIV with newly diagnosed TB. METHODS: A subset of 138 PLHIV from the 'SOUTH' study on outcomes related to TB and antiretroviral drug concentrations were included. Bacterial load was estimated by Mycobacterium Growth Indicator Tubes (MGIT) culture time-to-positivity (TTP) and Lowenstein Jensen (LJ) colony counts. Changes in TTP and colony counts were analyzed with Poisson Generalised Estimating Equations (GEE) and multilevel ordered logistic regression models, respectively, while time to culture negativity analysed with Cox proportional hazard models. ROC curves were used to explore the accuracy of the ct value in predicting culture negativity. RESULTS: A total of 81 patients (58.7%) were males, median age 34 (IQR 29  ̶ 40) years, median CD4 cell count of 180 (IQR 68  ̶ 345) cells/µL and 77.5% were ART naive. The median baseline ct value was 25.1 (IQR 21.0  ̶ 30.1). A unit Increase in the ct value was associated with a 5% (IRR = 1.05 95% CI 1.04  ̶ 1.06) and 3% (IRR = 1.03 95% CI 1.03  ̶ 1.04) increase in TTP at week 2 and 4 respectively. With LJ culture, a patient's colony grade was reduced by 0.86 times (0R = 0.86 95% CI 0.74  ̶ 0.97) at week 2 and 0.84 times (OR = 0.84 95% CI 0.79  ̶ 0.95 P = 0.002) at week 4 for every unit increase in the baseline ct value. There was a 3% higher likelihood of earlier conversion to negativity for every unit increase in the ct value. A ct cut point ≥28 best predicted culture negativity at week 4 with a sensitivity of 91. 7% & specificity 53.7% while a cut point ≥23 best predicted culture negativity at week 8. CONCLUSION: Baseline Xpert MTB/RIF ct values predict sputum conversion in PLHIV on anti-TB treatment. Surrogate biomarkers for sputum conversion in PLHIV are still a research priority.


Assuntos
Carga Bacteriana/métodos , Infecções por HIV/epidemiologia , Mycobacterium tuberculosis/isolamento & purificação , Escarro/microbiologia , Tuberculose Pulmonar/diagnóstico , Adulto , Antirretrovirais/sangue , Antituberculosos/uso terapêutico , Contagem de Linfócito CD4 , Contagem de Colônia Microbiana , Feminino , Infecções por HIV/sangue , Humanos , Masculino , Técnicas de Amplificação de Ácido Nucleico , Razão de Chances , Estudos Retrospectivos , Sensibilidade e Especificidade , Tuberculose Pulmonar/tratamento farmacológico , Tuberculose Pulmonar/epidemiologia , Uganda/epidemiologia
2.
BMC Infect Dis ; 21(1): 463, 2021 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-34020607

RESUMO

BACKGROUND: Streptococcus pyogenes causes a profound global burden of morbidity and mortality across its diverse clinical spectrum. To support a new controlled human infection ('challenge') model seeking to accelerate S. pyogenes vaccine development, we aimed to develop an accurate and reliable molecular method for quantifying bacterial load from pharyngeal swabs collected during experimental human pharyngitis. METHODS: Combined sequential RNA + DNA extraction from throat swabs was compared to traditional separate RNA-only and DNA-only extractions. An emm-type specific qPCR was developed to detect the emm75 challenge strain. Results from the qPCR were compared to culture, using throat swab samples collected in a human challenge study. RESULTS: The qPCR was 100% specific for the emm75 challenge strain when tested against a panel of S. pyogenes emm-types and other respiratory pathogens. Combined RNA + DNA extraction had similar yield to traditional separate extractions. The combined extraction method and emm75 qPCR had 98.8% sensitivity compared to culture for throat swabs collected from challenge study participants. CONCLUSIONS: We have developed a reliable molecular method for measuring S. pyogenes bacterial load from throat swabs collected in a controlled human infection model of S. pyogenes pharyngitis. TRIAL REGISTRATION: NCT03361163 on 4th December 2017.


Assuntos
Antígenos de Bactérias/genética , Carga Bacteriana , Proteínas da Membrana Bacteriana Externa/genética , Faringite/microbiologia , Reação em Cadeia da Polimerase em Tempo Real/métodos , Infecções Estreptocócicas/microbiologia , Streptococcus pyogenes/genética , Adulto , DNA Bacteriano/genética , DNA Bacteriano/isolamento & purificação , Seguimentos , Voluntários Saudáveis , Humanos , RNA Bacteriano/genética , RNA Bacteriano/isolamento & purificação , Sensibilidade e Especificidade , Streptococcus pyogenes/classificação , Streptococcus pyogenes/isolamento & purificação
3.
BMC Infect Dis ; 21(1): 466, 2021 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-34022850

RESUMO

BACKGROUND: Pulmonary tuberculosis (TB) in people living with HIV (PLH) frequently presents as sputum smear-negative. However, clinical trials of TB in adults often use smear-positive individuals to ensure measurable bacterial responses following initiation of treatment, thereby excluding HIV-infected patients from trials. METHODS: In this prospective case cohort study, 118 HIV-seropositive TB patients were assessed prior to initiation of standard four-drug TB therapy and at several time points through 35 days. Sputum bacillary load, as a marker of treatment response, was determined serially by: smear microscopy, Xpert MTB/RIF, liquid culture, and colony counts on agar medium. RESULTS: By all four measures, patients who were baseline smear-positive had higher bacterial loads than those presenting as smear-negative, until day 35. However, most smear-negative PLH had significant bacillary load at enrolment and their mycobacteria were cleared more rapidly than smear-positive patients. Smear-negative patients' decline in bacillary load, determined by colony counts, was linear to day 7 suggesting measurable bactericidal activity. Moreover, the decrease in bacterial counts was comparable to smear-positive individuals. Increasing cycle threshold values (Ct) on the Xpert assay in smear-positive patients to day 14 implied decreasing bacterial load. CONCLUSION: Our data suggest that smear-negative PLH can be included in clinical trials of novel treatment regimens as they contain sufficient viable bacteria, but allowances for late exclusions would have to be made in sample size estimations. We also show that increases in Ct in smear-positive patients to day 14 reflect treatment responses and the Xpert MTB/RIF assay could be used as biomarker for early treatment response.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS , Antituberculosos/uso terapêutico , Carga Bacteriana/efeitos dos fármacos , Soropositividade para HIV , HIV/imunologia , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/isolamento & purificação , Escarro/microbiologia , Tuberculose Pulmonar/tratamento farmacológico , Infecções Oportunistas Relacionadas com a AIDS/tratamento farmacológico , Infecções Oportunistas Relacionadas com a AIDS/virologia , Adulto , Fármacos Anti-HIV/uso terapêutico , Testes Diagnósticos de Rotina , Feminino , Seguimentos , Soropositividade para HIV/tratamento farmacológico , Soropositividade para HIV/virologia , Humanos , Masculino , Microscopia , Técnicas de Amplificação de Ácido Nucleico , Estudos Prospectivos , Resultado do Tratamento , Tuberculose Pulmonar/virologia
4.
Front Immunol ; 12: 618569, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34046029

RESUMO

Glucocorticoids are effective drugs for treating immune-related diseases, but prolonged therapy is associated with an increased risk of various infectious diseases, including tuberculosis. In this study, we have used a larval zebrafish model for tuberculosis, based on Mycobacterium marinum (Mm) infection, to study the effect of glucocorticoids. Our results show that the synthetic glucocorticoid beclomethasone increases the bacterial burden and the dissemination of a systemic Mm infection. The exacerbated Mm infection was associated with a decreased phagocytic activity of macrophages, higher percentages of extracellular bacteria, and a reduced rate of infected cell death, whereas the bactericidal capacity of the macrophages was not affected. The inhibited phagocytic capacity of macrophages was associated with suppression of the transcription of genes involved in phagocytosis in these cells. The decreased bacterial phagocytosis by macrophages was not specific for Mm, since it was also observed upon infection with Salmonella Typhimurium. In conclusion, our results show that glucocorticoids inhibit the phagocytic activity of macrophages, which may increase the severity of bacterial infections like tuberculosis.


Assuntos
Glucocorticoides/efeitos adversos , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Infecções por Mycobacterium não Tuberculosas/imunologia , Infecções por Mycobacterium não Tuberculosas/microbiologia , Mycobacterium marinum/efeitos dos fármacos , Mycobacterium marinum/imunologia , Fagocitose/efeitos dos fármacos , Fagocitose/imunologia , Animais , Carga Bacteriana , Beclometasona/metabolismo , Imunofenotipagem , Imunossupressores/efeitos adversos , Ativação de Macrófagos/efeitos dos fármacos , Ativação de Macrófagos/genética , Ativação de Macrófagos/imunologia , Macrófagos/metabolismo , Infecções por Mycobacterium não Tuberculosas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Receptores de Glucocorticoides/metabolismo , Peixe-Zebra
5.
Int J Food Microbiol ; 350: 109228, 2021 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-34023681

RESUMO

Raw milk may contain pathogenic microorganism that can seriously affect the health of consumers. In Southwest Ethiopia, raw cow milk is consumed more than the processed products, but its microbiological quality and its predictors are not studied well. The aim of this study was to determine the microbial quality of raw cow milk and its predictors along the dairy value chain in Southwest Ethiopia. A total of 150 milk and 300 environmental samples were collected randomly from dairy farms, milk distribution centers, and retailer outlets for microbiological analysis using standard protocols. One milk handler from each milk production or distribution stage was also interviewed to assess the knowledge, attitude, and practices regarding milk handling. Descriptive statistics and multiple linear regression models were used to summarize the data and to identify predictors of milk microbial quality, respectively. As the milk transported from dairy farm to milk retailer outlet, the mean total bacterial count has increased from 5.0 ±â€¯0.3 to 7.2 ±â€¯0.1 log CFU/ml respectively. The mean coliform count of the milk sample was 4.4 ±â€¯0.4 log CFU/ml at the dairy farm and 7.0 ±â€¯0.2 log CFU/ml at milk selling points, indicating the deterioration of milk quality along the dairy value chain. All of the analyzed water samples were positive for fecal coliform bacteria. The highest coliform bacteria were reported from milk storage equipment found at milk retailer outlet with the count of 4.8 ±â€¯0.5 log CFU/ml. Educational status and attitude of milk handlers and the quality of water used to wash milk equipment and hands of milk handlers were the major factors affecting the microbial quality of raw cow milk. The findings of this study revealed that the microbial quality of raw milk in the study area was poor. Hence, improving the attitude and educational status of milk handlers, and the quality of water is an important step to enhance milk quality and consequently to prevent milk borne diseases.


Assuntos
Carga Bacteriana , Bactérias Gram-Negativas , Leite/microbiologia , Alimentos Crus/microbiologia , Animais , Bovinos , Indústria de Laticínios/métodos , Etiópia , Fazendeiros , Fezes/microbiologia , Feminino
6.
Microb Pathog ; 156: 104936, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33951540

RESUMO

Motivated by conventional medicines' ineffectiveness and the appearance of bacterial resistance, homeopathic medicines are being increasingly demanded by the veterinary market. Dog feces contain high bacterial and pathogenic loads, which can cause diseases in animals and facilitate zoonotic transmission. Adequate animal immunity contributes to the elimination of potential pathogens. This work's objective was to evaluate the effects of using a homeopathic medication on blood cell counts, serum protein levels, and fecal bacterial counts in dogs. Two groups were used, each including five 19-month-old Beagle dogs. The homeopathic product Orgainfecto® was sprayed on the two daily meals in the treated group (T), at 0.5 mL/animal/day for 60 days; the group that did not receive the homeopathic was considered the control (C), who were fed only the vehicle used in the production of the homeopathic as a placebo. On days 1, 30, and 60, individual stool samples were collected for bacterial counts in the stool, blood samples for blood counts, and serum for biochemical tests. Total bacterial counts in feces were lower in group T on days 30 and 60 of the experiment, while total coliforms and E coli. were lower in this group on day 60. Total leukocyte counts were lower on day 60 in group T, unlike the neutrophil count, higher in group T on day 30, and eosinophils on day 60. However, the lymphocyte count was lower in group T on days 30 and 60. There was an increase in globulin and total protein in group T on day 60. We conclude that the tested homeopathic causes neutrophils and eosinophils' stimulation and increases globulins levels even with reduced lymphocytes. The daily consumption of homeopathic by dogs decreases the intestinal bacterial load, resulting in less environmental contamination and animal and human colibacillosis risks.


Assuntos
Homeopatia , Materia Medica , Animais , Carga Bacteriana , Cães , Escherichia coli , Fezes
7.
Int J Mol Sci ; 22(7)2021 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-33810600

RESUMO

Tuberculosis (TB) is a disease caused by Mycobacterium tuberculosis (Mtb) infection with the formation of a broad range of abnormal lung lesions within a single patient. Although host-pathogen interactions determine disease outcome, they are poorly understood within individual lesions at different stages of maturation. We compared Mtb load in a tuberculoma wall and the lung tissue distant from tuberculomas in TB patients. These data were combined with an analysis of activation and bactericidal statuses of alveolar macrophages and other cell subtypes examined both in ex vivo culture and on the histological sections obtained from the same lung lesions. The expression of pattern recognition receptors CD14, CD11b, and TLR-2, transcription factors HIF-1α, HIF-2α, and NF-κB p50 and p65, enzymes iNOS and COX-2, reactive oxygen species (ROS) biosynthesis, and lipid production were detected for various lung lesions, with individual Mtb loads in them. The walls of tuberculomas with insufficient inflammation and excessive fibrosis were identified as being the main niche for Mtb survival (single or as colonies) in non-foamy alveolar macrophages among various lung lesions examined. The identification of factors engaged in the control of Mtb infection and tissue pathology in local lung microenvironments, where host-pathogen relationships take place, is critical for the development of new therapeutic strategies.


Assuntos
Carga Bacteriana , Regulação da Expressão Gênica , Pulmão/microbiologia , Macrófagos Alveolares/microbiologia , Tuberculose Pulmonar/microbiologia , Adulto , Antibacterianos , Proliferação de Células , Técnicas Citológicas , Testes Diagnósticos de Rotina , Fibrose/imunologia , Perfilação da Expressão Gênica , Interações Hospedeiro-Patógeno , Humanos , Sistema Imunitário , Inflamação/patologia , Pulmão/patologia , Macrófagos Alveolares/patologia , Mycobacterium tuberculosis , Espécies Reativas de Oxigênio , Tuberculose/microbiologia , Adulto Jovem
8.
J Pediatr Gastroenterol Nutr ; 72(5): 756-762, 2021 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-33847290

RESUMO

OBJECTIVES: This project aims at comparing the impact of Holder pasteurization (HoP) and high-pressure processing (HPP) on bacterial load and retention of immunological components in human milk. METHODS: Human milk samples discarded by the Public Mothers' milk bank (Montreal, Canada) for bacterial purpose were pooled (n = 6) and pasteurized either by heating in a water bath (62.5°C, 30 minutes) or by HPP treatment (425 MPa, four cycles of 6 minutes, initial milk temperature of 4°C or 37°C). Bacterial load, lysozyme activity, and levels of immunoglobulins, lactoferrin, lipase, and 26 cytokines were analyzed. Untreated milk samples from same pools served as control. RESULTS: HPP treatment of milk allows a similar elimination of bacteria than HoP; bacterial counts were under the detection limit [<3 colony-forming units (CFU)/mL] in 50% of milk pools after HPP treatment, compared to 17% for HoP. With initial heating of samples to 37°C before HPP treatment, inactivation to an extent under the detection limit was reached in 67% of pools. There is no significant difference in IgA, lysozyme, and cytokines concentrations between untreated milk and all treatment methods. While no significant difference was observed in the amount of lipase (P > 0.07) and IgG (P > 0.11) between untreated milk and HPP-treated milk samples, HoP seems to be damaging for these factors (P < 0.04). IgM is well preserved in HPP-4°C samples compared to untreated milk (P = 0.07) whereas a decrease is observed for this immunoglobulin levels in HPP-37°C and HoP samples (P < 0.01). Lactoferrin activity, is well maintained in HPP-37°C milk samples in comparison to untreated milk samples (P = 0.52). A decrease in activity of this molecule is noted for samples treated with HPP at 4°C (P = 0.02) and this decrease is even more pronounced for HoP samples (P = 0.004). CONCLUSIONS: HPP is a promising alternative to HoP for treatment of human milk intended to preterm babies. Our results demonstrate that HPP treatment of human milk provides safe milk with less detrimental effects on the biochemically and immunologically active milk components than HoP.


Assuntos
Bancos de Leite , Leite Humano , Carga Bacteriana , Canadá , Humanos , Recém-Nascido , Pasteurização
9.
Food Microbiol ; 98: 103793, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33875221

RESUMO

This study investigated the relationship between the bacterial communities of bulk tank milk (BTM) and water used in Brazilian dairy farms. We also explored the association between BTM microbiota and its quality parameters (i.e., somatic cell count [SCC] and total bacteria count [TBC]). Water and BTM samples were collected twice for high throughput metataxonomic characterization. Milk samples were collected for SCCs, TBCs, and antimicrobial residue analysis. Water samples were submitted for physico-chemical and microbiological analyses. Overall, the BTM bacterial community was not influenced by the water microbiota. Furthermore, a higher number of Bacillus spp. and a tendency toward a higher number of Lactococcus spp. was associated with a higher TBC, and consequently could be used as an indicator of milk quality. A higher number of Streptococcus spp. and a tendency toward a higher number of Staphylococcus spp. were associated with a higher SCC. Apart from a variation on the content of the Bacillus taxa, no effect of sampling time on BTM bacterial community was observed. Finally, a negative correlation between the number of different species (richness) on BTM and SCC was found.


Assuntos
Bactérias/crescimento & desenvolvimento , Água Doce/microbiologia , Microbiota , Leite/microbiologia , Animais , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Carga Bacteriana , Brasil , Bovinos , Fazendeiros , Feminino
10.
Nutrients ; 13(3)2021 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-33799564

RESUMO

The prebiotic effect of high ß-glucan barley (HGB) flour on the innate immune system of high-fat model mice was investigated. C57BL/6J male mice were fed a high-fat diet supplemented with HGB flour for 90 days. Secretory immunoglobulin A (sIgA) in the cecum and serum were analyzed by enzyme-linked immunosorbent assays (ELISA). Real-time PCR was used to determine mRNA expression levels of pro- and anti-inflammatory cytokines such as interleukin (IL)-10 and IL-6 in the ileum as well as the composition of the microbiota in the cecum. Concentrations of short-chain fatty acids (SCFAs) and organic acids were analyzed by GC/MS. Concentrations of sIgA in the cecum and serum were increased in the HGB group compared to the control. Gene expression levels of IL-10 and polymeric immunoglobulin receptor (pIgR) significantly increased in the HGB group. HGB intake increased the bacterial count of microbiota, such as Bifidobacterium and Lactobacillus. Concentrations of propionate and lactate in the cecum were increased in the HGB group, and a positive correlation was found between these organic acids and the IL-10 expression level. Our findings showed that HGB flour enhanced immune function such as IgA secretion and IL-10 expression, even when the immune system was deteriorated by a high-fat diet. Moreover, we found that HGB flour modulated the gut microbiota, which increased the concentration of SCFAs, thereby stimulating the immune system.


Assuntos
Ceco/imunologia , Farinha , Hordeum , Íleo/imunologia , Obesidade/imunologia , Prebióticos , beta-Glucanas/análise , Animais , Carga Bacteriana , Peso Corporal , Ácidos Carboxílicos/análise , Ceco/química , Ceco/microbiologia , Citocinas/genética , Citocinas/metabolismo , Dieta , Ingestão de Alimentos , Ácidos Graxos Voláteis/análise , Fezes/química , Microbioma Gastrointestinal , Perfilação da Expressão Gênica , Íleo/metabolismo , Imunoglobulina A Secretora/análise , Imunoglobulina A Secretora/sangue , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Tamanho do Órgão , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores de Imunoglobulina Polimérica/genética , Receptores de Imunoglobulina Polimérica/metabolismo
11.
Int J Mol Sci ; 22(6)2021 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-33804806

RESUMO

Peritoneal resident macrophages play a key role in combating sepsis in the peritoneal cavity. We sought to determine if peritoneal transplantation of embryonic Myb- "peritoneal-like" macrophages attenuate abdominal fecal sepsis. Directed differentiation of rodent pluripotent stem cells (PSCs) was used in factor-defined media to produce embryonic-derived large "peritoneal-like" macrophages (Ed-LPM) that expressed peritoneal macrophage markers and demonstrated phagocytic capacity. Preclinical in vivo studies determined Ed-LPM efficacy in rodent abdominal fecal sepsis with or without Meropenem. Ex vivo studies explored the mechanism and effects of Ed-LPM on host immune cell number and function, including phagocytosis, reactive oxygen species (ROS) production, efferocytosis and apoptosis. Ed-LPM reduced sepsis severity by decreasing bacterial load in the liver, spleen and lungs. Ed-LPM therapy significantly improved animal survival by ~30% and reduced systemic bacterial burden to levels comparable to Meropenem therapy. Ed-LPM therapy decreased peritoneal TNFα while increasing IL-10 concentrations. Ed-LPMs enhanced peritoneal macrophage phagocytosis of bacteria, increased macrophage production of ROS and restored homeostasis via apoptosis and efferocytosis-induced clearance of neutrophils. In conclusion, Ed-LPM reduced systemic sepsis severity, improved survival and reduced bacterial load by enhancing peritoneal macrophage bacterial phagocytosis and killing and clearance of intra-peritoneal neutrophils. Macrophage therapy may be a potential strategy to address sepsis.


Assuntos
Carga Bacteriana , Macrófagos/imunologia , Macrófagos/metabolismo , Proteínas Proto-Oncogênicas c-myb/deficiência , Sepse/etiologia , Sepse/metabolismo , Animais , Citocinas/metabolismo , Modelos Animais de Doenças , Contagem de Leucócitos , Macrófagos Peritoneais/imunologia , Macrófagos Peritoneais/metabolismo , Neutrófilos/imunologia , Neutrófilos/metabolismo , Fagocitose/imunologia , Prognóstico , Ratos , Sepse/diagnóstico , Sepse/mortalidade , Índice de Gravidade de Doença
12.
BMC Infect Dis ; 21(1): 331, 2021 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-33832460

RESUMO

BACKGROUND: Previous studies have reported that presence and severity of Buruli ulcer (BU) may reflect the underlying immunosuppression in HIV infected individuals by causing increased incidence of multiple, larger and ulcerated lesions. We report cases of BU-HIV coinfection and the accompanying programmatic challenges encountered in central Ghana. METHODS: Patients with PCR confirmed BU in central Ghana who were HIV positive were identified and their BU01 forms were retrieved and reviewed in further detail. A combined 16S rRNA reverse transcriptase / IS2404 qPCR assay was used to assess the Mycobacterium ulcerans load. The characteristics of coinfected patients (BU+HIV+) were compared with a group of matched controls. RESULTS: The prevalence of HIV in this BU cohort was 2.4% (compared to national HIV prevalence of 1.7%). Eight of 9 BU+HIV+ patients had a single lesion and ulcers were the most common lesion type. The lesions presented were predominantly category II (5/9) followed by category I lesions. The median (IQR) time to healing was 14 (8-28) weeks in the BU+HIV+ compared to 28 (12-33) weeks in the control BU+HIV- group (p = 0.360). Only one BU+HIV+ developed a paradoxical reaction at week 16 but the lesion healed completely at week 20. The median bacterial load (16SrRNA) of BU+HIV+ patients was 750 copies /ml (95% CI 0-398,000) versus 500 copies/ml (95% CI 0-126,855,500) in BU+HIV- group. Similarly, the median count using the IS2404 assay was 500 copies/ml (95% CI 0-500) for BU+HIV+ patients versus 500 copies/ml (95% CI 500-31,000) for BU+HIV- patients. BU+HIV- patients mounted a significantly higher interferon-γ response compared to the BU+HIV+ co-infected patients with respective median (range) responses of [1687(81.11-4399) pg/ml] versus [137.5(4.436-1406) pg/ml, p = 0.03]. There were challenges with the integration of HIV and BU care in this cohort. CONCLUSION: The prevalence of HIV in the BU+ infected population was not significantly increased when compared to the prevalence of HIV in the general population. There was no clear relationship between BU lesion severity and HIV viral load or CD4 counts. Efforts should be made to encourage the integration of care of patients with BU-HIV coinfection.


Assuntos
Úlcera de Buruli/epidemiologia , Úlcera de Buruli/etiologia , Infecções por HIV/epidemiologia , Adolescente , Adulto , Carga Bacteriana , Úlcera de Buruli/tratamento farmacológico , Úlcera de Buruli/virologia , Contagem de Linfócito CD4 , Coinfecção/epidemiologia , Coinfecção/microbiologia , Coinfecção/virologia , Feminino , Gana/epidemiologia , Infecções por HIV/tratamento farmacológico , Infecções por HIV/microbiologia , Humanos , Masculino , Pessoa de Meia-Idade , Mycobacterium ulcerans/genética , Prevalência , RNA Ribossômico 16S , Reação em Cadeia da Polimerase em Tempo Real , Estudos Retrospectivos , Carga Viral , Cicatrização , Adulto Jovem
13.
Int J Food Microbiol ; 347: 109198, 2021 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-33894462

RESUMO

The U.S. FDA Food Safety Modernization Act Preventive Controls for Human Food Rule underlines the importance of an effective environmental monitoring (EM) program. EM is used to determine harborage sites of microorganisms on processing equipment, assess effectiveness of sanitation programs, and prevent transmission of foodborne pathogens. This study characterizes commercially-available polyurethane foam (PUF) and cellulose (CELL) EM tools for their efficacy in the release of foodborne pathogens from their sponge matrices. Specifically, the objectives of this study were to 1) compare the ability of EM tools to release microorganisms into a recovery eluent, 2) characterize EM tool performance at decreasing inoculum concentrations, and 3) assess the impact of various operators during the processing of EM samples. Two bacteria (Listeria monocytogenes, Salmonella Typhimurium) and one human norovirus surrogate (Tulane virus [TV]) were compared at decreasing inoculum levels utilizing two elution techniques (mechanical stomacher, manually by operator), and across six operators. Data indicated that EM tool material composition impacted the release of microorganisms (p = 0.0001), where the PUF EM tool released TV more readily than the CELL EM tool. Conversely, the decreasing inoculum levels did not statistically differ in the release of microorganisms from the EM tool matrices. In addition, no significant difference was found between the machine stomacher and manual elution by human operator or between operators. Overall, the study provides a detailed characterization of two commercially-available EM tools, and the differences identified in this study can be used to improve the effectiveness of EM programs.


Assuntos
Celulose/farmacologia , Monitoramento Ambiental/métodos , Listeria monocytogenes/isolamento & purificação , Norovirus/isolamento & purificação , Poliuretanos/farmacologia , Salmonella typhimurium/isolamento & purificação , Carga Bacteriana/métodos , Contagem de Colônia Microbiana , Microbiologia de Alimentos , Inocuidade dos Alimentos , Humanos , Listeria monocytogenes/genética , Norovirus/genética , Salmonella typhimurium/genética , Carga Viral/métodos
14.
Int J Food Microbiol ; 347: 109192, 2021 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-33836444

RESUMO

Brucellosis is one of the most prevalent zoonotic diseases with worldwide distribution. Although the incidence of brucellosis varies widely in different regions, it is a major concern for public health around the world. This study aimed to determine the prevalence and quantity of Brucella spp. in sheep and goat raw milk, as well as artisanal cheeses produced in the North-west of Iran. To evaluate the intrinsic parameters that may affect the survival of Brucella spp., some of the cheese properties (e.g., pH, salt, moisture, and storage time before selling) were also assessed. A total of 572 samples consisting in 214 sheep raw milk, 92 goat raw milk, and 266 local artisanal cheese samples were collected. The artisanal cheeses were manufactured from a mixture of raw sheep and goat milk. According to the results, using quantitative real-time PCR (qPCR), 17.29%, 15.22%, and 22.93% of the sheep raw milk, goat raw milk, and artisanal cheese samples were found positive for Brucella spp., respectively. In comparison with culture assay, qPCR was 3.5 to 5 times (p < 0.05) more sensitive in the detection of Brucella spp. The results also revealed that the mean values of Brucella spp. load in sheep and goat raw milk and artisanal cheeses were 1.22, 1.55, and 1.43 log cell/ml or g, respectively. A positive correlation was found between Brucella load and successful detection of Brucella spp. by culture assay. Data also suggested a correlation (p < 0.01) between the load of Brucella spp. estimated by qPCR and pH value, salt content, and storage period of the cheese samples. However, Brucella spp. load did not correlate significantly with the moisture content. Based on the results, in any of the cheese samples with a pH value less than 4.5 and a storage period more than five months, no contamination with Brucella spp. was detected.


Assuntos
Brucella/isolamento & purificação , Queijo/microbiologia , Leite/microbiologia , Animais , Carga Bacteriana , Técnicas Bacteriológicas , Brucella/genética , Queijo/análise , Armazenamento de Alimentos , Cabras , Irã (Geográfico) , Prevalência , Reação em Cadeia da Polimerase em Tempo Real , Ovinos
15.
Int J Mol Sci ; 22(6)2021 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-33805837

RESUMO

For over 50 years, patients with drug-sensitive and drug-resistant tuberculosis have undergone long, arduous, and complex treatment processes with several antimicrobials. With the prevalence of drug-resistant strains on the rise and new therapies for tuberculosis urgently required, we assessed whether manipulating iron levels in macrophages infected with mycobacteria offered some insight into improving current antimicrobials that are used to treat drug-resistant tuberculosis. We investigated if the iron chelator, desferrioxamine, can support the function of human macrophages treated with an array of second-line antimicrobials, including moxifloxacin, bedaquiline, amikacin, clofazimine, linezolid and cycloserine. Primary human monocyte-derived macrophages were infected with Bacillus Calmette-Guérin (BCG), which is pyrazinamide-resistant, and concomitantly treated for 5 days with desferrioxamine in combination with each one of the second-line tuberculosis antimicrobials. Our data indicate that desferrioxamine used as an adjunctive treatment to bedaquiline significantly reduced the bacterial load in human macrophages infected with BCG. Our findings also reveal a link between enhanced bactericidal activity and increases in specific cytokines, as the addition of desferrioxamine increased levels of IFN-γ, IL-6, and IL-1ß in BCG-infected human monocyte-derived macrophages (hMDMs) treated with bedaquiline. These results provide insight, and an in vitro proof-of-concept, that iron chelators may prove an effective adjunctive therapy in combination with current tuberculosis antimicrobials.


Assuntos
Antituberculosos/farmacologia , Desferroxamina/farmacologia , Diarilquinolinas/farmacologia , Quelantes de Ferro/farmacologia , Ferro/metabolismo , Macrófagos/efeitos dos fármacos , Mycobacterium bovis/efeitos dos fármacos , Amicacina/farmacologia , Carga Bacteriana/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Clofazimina/farmacologia , Ciclosserina/farmacologia , Farmacorresistência Bacteriana/efeitos dos fármacos , Sinergismo Farmacológico , Expressão Gênica , Humanos , Interferon gama/genética , Interferon gama/imunologia , Interleucina-1beta/genética , Interleucina-1beta/imunologia , Interleucina-6/genética , Interleucina-6/imunologia , Linezolida/farmacologia , Macrófagos/imunologia , Macrófagos/microbiologia , Testes de Sensibilidade Microbiana , Moxifloxacina/farmacologia , Mycobacterium bovis/crescimento & desenvolvimento , Mycobacterium bovis/metabolismo , Cultura Primária de Células , Pirazinamida/farmacologia
16.
Nat Commun ; 12(1): 2126, 2021 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-33837203

RESUMO

There is accumulating evidence that the lower airway microbiota impacts lung health. However, the link between microbial community composition and lung homeostasis remains elusive. We combine amplicon sequencing and bacterial culturing to characterize the viable bacterial community in 234 longitudinal bronchoalveolar lavage samples from 64 lung transplant recipients and establish links to viral loads, host gene expression, lung function, and transplant health. We find that the lung microbiota post-transplant can be categorized into four distinct compositional states, 'pneumotypes'. The predominant 'balanced' pneumotype is characterized by a diverse bacterial community with moderate viral loads, and host gene expression profiles suggesting immune tolerance. The other three pneumotypes are characterized by being either microbiota-depleted, or dominated by potential pathogens, and are linked to increased immune activity, lower respiratory function, and increased risks of infection and rejection. Collectively, our findings establish a link between the lung microbial ecosystem, human lung function, and clinical stability post-transplant.


Assuntos
Rejeição de Enxerto/microbiologia , Transplante de Pulmão/efeitos adversos , Pulmão/microbiologia , Microbiota/imunologia , Pneumonia Bacteriana/microbiologia , Adulto , Aloenxertos/imunologia , Aloenxertos/microbiologia , Bactérias/genética , Bactérias/imunologia , Bactérias/isolamento & purificação , Bactérias/patogenicidade , Carga Bacteriana/imunologia , Técnicas Bacteriológicas , Líquido da Lavagem Broncoalveolar/microbiologia , Broncoscopia , DNA Bacteriano/isolamento & purificação , Feminino , Rejeição de Enxerto/diagnóstico , Rejeição de Enxerto/imunologia , Humanos , Tolerância Imunológica , Estudos Longitudinais , Pulmão/imunologia , Masculino , Metagenômica , Microbiota/genética , Pessoa de Meia-Idade , Pneumonia Bacteriana/diagnóstico , Pneumonia Bacteriana/imunologia , Estudos Prospectivos , RNA Ribossômico 16S/genética
17.
PLoS Negl Trop Dis ; 15(3): e0008970, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33705392

RESUMO

Leptospira interrogans is a pathogenic spirochete responsible for leptospirosis, a neglected, zoonotic reemerging disease. Humans are sensitive hosts and may develop severe disease. Some animal species, such as rats and mice can become asymptomatic renal carriers. More than 350 leptospiral serovars have been identified, classified on the basis of the antibody response directed against the lipopolysaccharide (LPS). Similarly to whole inactivated bacteria used as human vaccines, this response is believed to confer only short-term, serogroup-specific protection. The immune response of hosts against leptospires has not been thoroughly studied, which complicates the testing of vaccine candidates. In this work, we studied the immunoglobulin (Ig) profiles in mice infected with L. interrogans over time to determine whether this humoral response confers long-term protection after homologous challenge six months post-infection. Groups of mice were injected intraperitoneally with 2×107 leptospires of one of three pathogenic serovars (Manilae, Copenhageni or Icterohaemorrhagiae), attenuated mutants or heat-killed bacteria. Leptospira-specific immunoglobulin (IgA, IgM, IgG and 4 subclasses) produced in the first weeks up to 6 months post-infection were measured by ELISA. Strikingly, we found sustained high levels of IgM in mice infected with the pathogenic Manilae and Copenhageni strains, both colonizing the kidney. In contrast, the Icterohaemorrhagiae strain did not lead to kidney colonization, even at high dose, and triggered a classical IgM response that peaked at day 8 post-infection and disappeared. The virulent Manilae and Copenhageni serovars elicited high levels and similar profiles of IgG subclasses in contrast to Icterohaemorrhagiae strains that stimulated weaker antibody responses. Inactivated heat-killed Manilae strains elicited very low responses. However, all mice pre-injected with leptospires challenged with high doses of homologous bacteria did not develop acute leptospirosis, and all antibody responses were boosted after challenge. Furthermore, we showed that 2 months post-challenge, mice pre-infected with the attenuated M895 Manilae LPS mutant or heat-killed bacterin were completely protected against renal colonization. In conclusion, we observed a sustained IgM response potentially associated with chronic leptospiral renal infection. We also demonstrated in mice different profiles of protective and cross-reactive antibodies after L. interrogans infection, depending on the serovar and virulence of strains.


Assuntos
Anticorpos Antibacterianos/sangue , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Leptospira interrogans/imunologia , Leptospirose/imunologia , Leptospirose/prevenção & controle , Animais , Carga Bacteriana/imunologia , Reações Cruzadas/imunologia , Feminino , Imunoglobulina A/sangue , Rim/microbiologia , Leptospirose/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL
18.
PLoS Negl Trop Dis ; 15(3): e0009102, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33735243

RESUMO

Brucellosis is a zoonotic disease imposing significant impacts on livestock production and public health worldwide. India is the world's leading milk producer and Punjab is the state which produces the most cattle and buffalo milk per capita. The aim of this study was to investigate the epidemiology of bovine brucellosis to provide evidence for control of the disease in Punjab State, India. A cross-sectional study of dairy farms was conducted in humans and livestock in rural Ludhiana district using a multi-stage sampling strategy. The study suggests that brucellosis is endemic at high levels in cattle and buffalo in the study area with 15.1% of large ruminants testing seropositive and approximately a third of dairy farms having at least one animal test seropositive. In total, 9.7% of those in direct contact with livestock tested seropositive for Brucella spp. Persons that assisted with calving and/or abortion within the last year on a farm with seronegative livestock and people which did not assist with calving/abortion had 0.35 (95% CI: 0.17 to 7.1) and 0.21 (0.09 to 0.46) times the odds of testing seropositive compared to persons assisting with calving/abortion in a seropositive farm, respectively. The study demonstrated that persons in direct contact with cattle and buffalo in the study area have high risk of exposure to Brucella spp. Control of the disease in livestock is likely to result in benefits to both animal and public health sectors.


Assuntos
Brucelose/epidemiologia , Brucelose/veterinária , Búfalos/microbiologia , Doenças dos Bovinos/epidemiologia , Bovinos/parasitologia , Animais , Carga Bacteriana , Brucella/imunologia , Brucelose/transmissão , Doenças dos Bovinos/parasitologia , Estudos Transversais , Indústria de Laticínios , Fazendeiros , Humanos , Índia , Gado/microbiologia , População Rural , Soroconversão , Estudos Soroepidemiológicos , Testes Sorológicos
19.
Sci Rep ; 11(1): 5887, 2021 03 15.
Artigo em Inglês | MEDLINE | ID: covidwho-1135699

RESUMO

Based on the current knowledge of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) transmission, wearing a mask has been recommended during the COVID-19 pandemic. Bacterial filtration efficiency (BFE) measurements enable designing and regulating medical masks to prevent bioaerosol dissemination; however, despite the simplicity of these measurements, several scientific questions remain unanswered regarding BFE tests. Here, we investigated (1) the impact of substituting 100-mm Petri dishes with 90-mm disposable Petri dishes, (2) the impact of colony-counting methods on the bioaerosol aerodynamic size, and (3) the impact of colony-counting methods on the total viable particle counts. We demonstrated that disposable 90-mm Petri dishes can be used to replace the 100-mm dishes. We also showed that an automatic high-resolution colony counter can be used to directly count viable particles on collection substrates and to measure the bioaerosol size parameters. Our results enable possible modernization of the outdated testing methods recommended in the US and European standards for BFE measurements. Specifically, use of a modernized colony counter should be clearly regulated and permitted to avoid the counting of positive holes. The median aerodynamic diameter appears to be the most relevant parameter for characterizing bioaerosol size.


Assuntos
Bactérias , Filtração/normas , Máscaras/normas , Carga Bacteriana , Microbiologia Ambiental , Filtração/métodos , Humanos , Máscaras/microbiologia , Tamanho da Partícula , Porosidade
20.
Sci Rep ; 11(1): 5887, 2021 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-33723303

RESUMO

Based on the current knowledge of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) transmission, wearing a mask has been recommended during the COVID-19 pandemic. Bacterial filtration efficiency (BFE) measurements enable designing and regulating medical masks to prevent bioaerosol dissemination; however, despite the simplicity of these measurements, several scientific questions remain unanswered regarding BFE tests. Here, we investigated (1) the impact of substituting 100-mm Petri dishes with 90-mm disposable Petri dishes, (2) the impact of colony-counting methods on the bioaerosol aerodynamic size, and (3) the impact of colony-counting methods on the total viable particle counts. We demonstrated that disposable 90-mm Petri dishes can be used to replace the 100-mm dishes. We also showed that an automatic high-resolution colony counter can be used to directly count viable particles on collection substrates and to measure the bioaerosol size parameters. Our results enable possible modernization of the outdated testing methods recommended in the US and European standards for BFE measurements. Specifically, use of a modernized colony counter should be clearly regulated and permitted to avoid the counting of positive holes. The median aerodynamic diameter appears to be the most relevant parameter for characterizing bioaerosol size.


Assuntos
Bactérias , Filtração/normas , Máscaras/normas , Carga Bacteriana , Microbiologia Ambiental , Filtração/métodos , Humanos , Máscaras/microbiologia , Tamanho da Partícula , Porosidade
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