RESUMO
Microbial food spoilage is responsible for significant economic losses. Brochothrix thermosphacta is one of the major bacteria involved in the spoilage of meat and seafood. Its growth and metabolic activities during food storage result in the production of metabolites associated with off-odors. In this study, we evaluated the genotypic and phenotypic diversity of this species. A collection of 161 B. thermosphacta strains isolated from different foods, spoiled or not, and from a slaughterhouse environment was constituted from various laboratory collections and completed with new isolates. A PCR test based on the rpoB gene was developed for a fast screening of B. thermosphacta isolates. Strains were typed by MALDI-TOF MS, rep-PCR, and PFGE. Each typing method separated strains into distinct groups, revealing significant intra-species diversity. These classifications did not correlate with the ecological origin of strains. The ability to produce acetoin and diacetyl, two molecules associated with B. thermosphacta spoilage, was evaluated in meat and shrimp juices. The production level was variable between strains and the spoilage ability on meat or shrimp juice did not correlate with the substrate origin of strains. Although the B. thermosphacta species encompasses ubiquitous strains, spoiling ability is both strain- and environment-dependent.
Assuntos
Brochothrix , Contaminação de Alimentos , Microbiologia de Alimentos , Genótipo , Fenótipo , Acetoína/metabolismo , Animais , Técnicas de Tipagem Bacteriana , Biodiversidade , Brochothrix/classificação , Brochothrix/genética , Brochothrix/isolamento & purificação , Brochothrix/metabolismo , Crustáceos/microbiologia , DNA Bacteriano/isolamento & purificação , Diacetil/metabolismo , Armazenamento de Alimentos , Genes Bacterianos/genética , Carne/microbiologia , Reação em Cadeia da Polimerase , Alimentos Marinhos/microbiologia , Especificidade da EspécieRESUMO
BACKGROUND: Prediction of prognosis is a key step of malignant pleural mesothelioma (MPM) management and treatment assignment. Aim of this study was to identify simple prognostic factors, focusing on inflammation-related parameters. METHODS: Baseline clinical and laboratory data were extracted from a single-center 20-year cohort of consecutive patients exhibiting a proven MPM. Inflammation-related ratios and composite scores were evaluated as prognostic indicators. RESULTS: 468 patients were identified. Mean age and BMI were 73.0 years and 25.1 kg/m2. The histologic subtype was epithelioid, sarcomatoid, or biphasic in 80.3%, 6.2%, and 13.5% of cases, respectively. Mean Neutrophil to Lymphocyte Ratio (NLR), systemic Inflammation Index (SII) and Advanced Lung cancer inflammation Index (ALI) were 5.8, 1,836.6, and 29.6. Median survival was 13.0 months. Univariate analyses revealed that age > 70 years, persistent asthenia, hemoglobin < 13 g/dL, and non-epithelioid histologic type were associated with poorer survival, as well as the following high-inflammation-related criteria: CRP > 25 mg/L, white blood cell count (WBC) > 109/dL, NLR > 5, SII > 1,270, and ALI < 18. Multivariate regression showed that age, histology, hemoglobin, and WBC were independent predictors of survival. Also, the inflammation-related factors ALI and NLR were independently associated with survival. Interestingly, hemoglobin was statistically significant predictor of survival in all multivariate models. We found higher proportion of survival > 18 months (66th percentile) in patients exhibiting SII < 2,000 and NLR < 5. CONCLUSION: The prognosis of MPM is strongly influenced by systemic inflammation and patients exhibiting higher NLR, SII and lower ALI have shorter survival, which strengthens the level of evidence about the major role played by inflammation in MPM.
Assuntos
Neoplasias Pulmonares , Mesotelioma Maligno , Mesotelioma , Neoplasias Pleurais , Idoso , Hemoglobinas , Humanos , Inflamação/patologia , Neoplasias Pulmonares/tratamento farmacológico , Mesotelioma/patologia , Neutrófilos/patologia , Neoplasias Pleurais/patologia , Prognóstico , Estudos RetrospectivosRESUMO
This study describes the construction of inducible bioluminescent strains via genetic engineering along with their characterization and optimization in the detection of heavy metals. Firstly, a preliminary comparative study enabled us to select a suitable carbon substrate from pyruvate, glucose, citrate, diluted Luria-Bertani, and acetate. The latter carbon source provided the best induction ratios for comparison. Results showed that the three constructed inducible strains, Escherichia coli DH1 pBzntlux, pBarslux, and pBcoplux, were usable when conducting a bioassay after a 14-h overnight culture at 30 °C. Utilizing these sensors gave a range of 12 detected heavy metals including several cross-detections. Detection limits for each metal were often close to and sometimes lower than the European standards for water pollution. Finally, in order to maintain sensitive bacteria within the future biosensor-measuring cell, the agarose immobilization matrix was compared to polyvinyl alcohol (PVA). Agarose was selected because the detection limits of the bioluminescent strains were not affected, in contrast to PVA. Specific detection and cross-detection ranges determined in this study will form the basis of a multiple metals detection system by the new multi-channel Lumisens3 biosensor.
Assuntos
Bactérias/efeitos dos fármacos , Técnicas Biossensoriais/métodos , Medições Luminescentes , Metais Pesados/análise , Bactérias/genética , Bactérias/metabolismo , Carbono/metabolismo , Reações Cruzadas , Engenharia Genética/métodos , Limite de Detecção , Proteínas Luminescentes/genética , Metais Pesados/toxicidade , Especificidade da EspécieRESUMO
This research study deals with the on-line detection of heavy metals and toxicity within the context of environmental pollution monitoring. It describes the construction and the proof of concept of a multi-channel bioluminescent bacterial biosensor in immobilized phase: Lumisens3. This new versatile device, designed for the non-stop analysis of water pollution, enables the insertion of any bioluminescent strains (inducible or constitutive), immobilized in a multi-well removable card. The technical design of Lumisens3 has benefited from both a classical and a robust approach and includes four main parts: (1) a dedicated removable card contains 64 wells, 3 mm in depth, arranged in eight grooves within which bacteria are immobilized, (2) this card is incubated on a Pelletier block with a CCD cooled camera on top for bioluminescence monitoring, (3) a fluidic network feeds the card with the sample to be analyzed and finally (4) a dedicated computer interface, BIOLUX 1.0, controls all the elements of the biosensor, allowing it to operate autonomously. The proof of concept of this biosensor was performed using a set of four bioluminescent bacteria (Escherichia coli DH1 pBzntlux, pBarslux, pBcoplux, and E. coli XL1 pBfiluxCDABE) in the online detection of CdCl(2) 0.5 µM and As(2)O(3) 5 µM from an influent. When considering metals individually, the "fingerprints" from the biosensor were as expected. However, when metals were mixed together, cross reaction and synergistic effects were detected. This biosensor allowed us to demonstrate the simultaneous on-line cross detection of one or several heavy metals as well as the measurement of the overall toxicity of the sample.
Assuntos
Bactérias/efeitos dos fármacos , Técnicas Biossensoriais/instrumentação , Monitoramento Ambiental/métodos , Medições Luminescentes , Metais Pesados/toxicidade , Técnicas Biossensoriais/métodos , Células Imobilizadas/metabolismo , Reações Cruzadas , Escherichia coli/efeitos dos fármacos , Proteínas Luminescentes , Metais Pesados/análise , Poluentes Químicos da Água/análiseRESUMO
Despite advances, malignant pleural mesothelioma (MPM) remains a challenging disease in terms of diagnosis, treatment, and overall management. Herein, we analyzed, in a large-scale single-center cohort, the characteristics and perioperative course of patients undergoing surgical diagnosis of MPM. We identified a total of 514 consecutive patients, 71.4% male and 28.6% female, with mean age 71.3 +/- 13.6 years. Most exhibited pleural, respiratory, or general symptoms and American Society of Anesthesiologists (ASA) score was ≥3 in 68.3% of cases. Thoracoscopy was the most frequent approach (92.0%) and short open thoracotomy was performed in the remaining patients. Pleurodesis was simultaneously performed in 74.3% of cases. Diagnostic failure led to redo surgery in 3.7% of patients. Non-epithelioid histology was found in 19.5% of MPMs and was significantly more frequent in right-sided MPM (p = 0.04), and in patients without history of cancer (p = 0.03), or pleural nodules at thoracoscopy (p = 0.01). Minor only or major complications occurred in respectively 7.8% and 3.6% of cases. They were more frequent in patients ≥ 70 years (p = 0.05) and Performance Status > 2 (p = 0.05). The mean hospital stay was 7.5 days. The 30-day and 90-day early mortality rates were 2.3% and 6.4%, respectively. Surgical diagnosis of MPM is a reliable procedure but is associated with significant morbidity and hospital-stay duration.