RESUMO
Butenolide is an environmentally friendly antifouling natural product, but its efficiency and mechanism in preventing biofilm formation have not been examined. Furthermore, controlling the release of butenolide from paints into seawater is technically challenging. A coating was developed by mixing butenolide with a biodegradable polymer, poly (ε-caprolactone)-based polyurethane, and a one-month in situ anti-biofilm test was conducted in a subtidal area. The constant release of butenolide from the surface suggested that its release was well controlled. Direct observation and confocal microscope investigation indicated that the coating was effective against both biofilm formation and attachment of large fouling organisms. Metatranscriptomic analysis of biofilm samples implied that the coating selectively inhibited the adhesion of microbes from a variety of phyla and targeted particular functional pathways including energy metabolism, drug transport and toxin release. These integrated analyses demonstrated the potential application of this butenolide/polymer coating as an anti-biofilm material.
Assuntos
4-Butirolactona/análogos & derivados , Biofilmes/efeitos dos fármacos , Incrustação Biológica/prevenção & controle , Consórcios Microbianos/genética , Poliésteres/farmacologia , Poliuretanos/farmacologia , 4-Butirolactona/farmacologia , Adesão Celular , Metagenômica , Água do Mar , Propriedades de Superfície , TranscriptomaRESUMO
Recent big data analyses have illuminated marine microbial diversity from a global perspective, focusing on planktonic microorganisms. Here, we analyze 2.5 terabases of newly sequenced datasets and the Tara Oceans metagenomes to study the diversity of biofilm-forming marine microorganisms. We identify more than 7,300 biofilm-forming 'species' that are undetected in seawater analyses, increasing the known microbial diversity in the oceans by more than 20%, and provide evidence for differentiation across oceanic niches. Generation of a gene distribution profile reveals a functional core across the biofilms, comprised of genes from a variety of microbial phyla that may play roles in stress responses and microbe-microbe interactions. Analysis of 479 genomes reconstructed from the biofilm metagenomes reveals novel biosynthetic gene clusters and CRISPR-Cas systems. Our data highlight the previously underestimated ocean microbial diversity, and allow mining novel microbial lineages and gene resources.
Assuntos
Biofilmes , Biodiversidade , Sistemas CRISPR-Cas/genética , Sistemas CRISPR-Cas/fisiologia , Metagenoma/genética , Água do Mar/microbiologiaRESUMO
BACKGROUND & AIMS: Patients undergoing gastrointestinal operations are at risk of malnutrition which may increase the chance of adverse surgical outcomes. This prospective study aimed at correlating nutritional status of patients having gastrointestinal operations with their short-term surgical outcomes captured by a territory-wide Surgical Outcomes Monitoring and Improvement Program. METHODS: The preoperative malnutrition risk of Chinese adult patients undergoing elective/emergency ultra-major/major gastrointestinal operations in two surgical departments over a 12-month period were assessed by Chinese version of Malnutrition Universal Screening Tool. Their perioperative risk factors and clinical outcomes, including length of hospital stay, mortality and morbidity, were retrieved from the above mentioned program. Correlation of malnutrition risk with clinical outcomes was assessed by logistic regression analysis after controlling for known confounders. RESULTS: 943 patients (58% male; mean age 65.9 ± 14.8 years) underwent gastrointestinal operations (40.3% emergency operation; 52.7% ultra-major procedures; 66.9% bowel resections) had analyzable data. 15.8% and 17.1% of patients were at medium and high risk of malnutrition, respectively. Malnutrition risk score according to the screening tool was an independent predictor of length of hospital stay, 30-day mortality, 60-day mortality and minor medical complications. Similar correlations were found for various sub-scores of malnutrition risk. Weight loss sub-score was predictive of 30-day mortality, 60-day mortality and minor medical complications. Body mass index was predictive of mortality (30- and 60- day) whereas the acute disease sub-score was predictive of length of hospital stay. CONCLUSIONS: Preoperative malnutrition was an important predictor of poor clinical outcomes in patients undergoing gastrointestinal operations in Hong Kong.