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1.
Extremophiles ; 28(2): 21, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38532228

RESUMO

Antarctica harbors a microbial diversity still poorly explored and of inestimable biotechnological value. Cold-adapted microorganisms can produce a diverse range of metabolites stable at low temperatures, making these compounds industrially interesting for biotechnological use. The present work investigated the biotechnological potential for antimicrobial and antitumor activity of filamentous fungi and bacteria isolated from marine sediment samples collected at Deception Island, Antarctica. A total of 89 microbial isolates were recovered from marine sediments and submitted to an initial screening for L-glutaminase with antitumoral activity and for antimicrobial metabolites. The isolates Pseudogymnoascus sp. FDG01, Pseudogymnoascus sp. FDG02, and Penicillium sp. FAD33 showed potential antiproliferative action against human pancreatic carcinoma cells while showing no toxic effect on non-tumor cells. The microbial extracts from unidentified three bacteria and four filamentous fungi showed antibacterial activity against at least one tested pathogenic bacterial strain. The isolate FDG01 inhibited four bacterial species, while the isolate FDG01 was active against Micrococcus luteus in the minimal inhibitory concentration of 0.015625 µg mL -1. The results pave the way for further optimization of enzyme production and characterization of enzymes and metabolites found and reaffirm Antarctic marine environments as a wealthy source of compounds potentially applicable in the healthcare and pharmaceutical industry.


Assuntos
Ascomicetos , Fungos , Humanos , Regiões Antárticas , Ascomicetos/metabolismo , Sedimentos Geológicos/microbiologia , Antibacterianos/metabolismo , Antibacterianos/farmacologia , Bactérias/metabolismo , Preparações Farmacêuticas/metabolismo
2.
Environ Res ; 246: 118150, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38218518

RESUMO

Improving anaerobic digestion of sugarcane vinasse - a high-strength wastewater from ethanol distillation - is a subject of great interest, in view of the reduction of the pollutants and recovery of methane and valuable metabolites as byproducts. Through metatranscriptomic analysis, this study evaluated the active microbiome and metabolic pathways in a continuous acidogenic reactor: Stage 1S (control): 100% sucrose-based substrate (SBS); Stage 2SV (acclimation): 50% SBS and 50% vinasse; Stage 3V: 100% vinasse. Metatranscriptome obtained from each Stage was subjected to taxonomic and functional annotations. Under SBS feeding, pH dropped to pH 2.7 and biohydrogen production was observed. As vinasse was added, pH increased to 4.1-4.5, resulting in community structure and metabolite changes. In Stage 3V, biohydrogen production ceased, and propionate and acetate prevailed among the volatile fatty acids. Release of homoacetogenesis enzymes by Clostridium ljungdahlii and of uptake hydrogenase (EC 1.12.99.6) by Pectinatus frisingensis were linked to hydrogen consumption in Stages 2SV and 3V. Metabolic pathways of vinasse compounds, such as carbohydrates, malate, oxalate, glycerol, sulfate and phenol, were investigated in detail. In pyruvate metabolism, gene transcripts of oadA (oxaloacetate decarboxylase) and mdh (malate dehydrogenase), were upregulated in Stage 3V, being mostly attributed to P. frisingensis. Acetate formation from vinasse degradation was mainly attributed to Megasphaera and Clostridium, and propionate formation to P. frisingensis. Glycerol removal from vinasse exceeded 99%, and gene transcripts encoding for glpF (glycerol uptake facilitator protein), glpK (glycerol kinase) and glpABC (glycerol-3-phosphate dehydrogenase) were expressed mostly by Pectinatus and Prevotella. mRNA profiling showed that active bacteria and gene expression greatly changed when vinasse replaced sucrose, and Pectinatus was the main active bacterium degrading the searched compounds from vinasse. The identification of the main metabolic routes and the associated microorganisms achieved in this work contributes with valuable information to support further optimization of fermentation towards the desired metabolites.


Assuntos
Microbiota , Saccharum , Fermentação , Saccharum/química , Saccharum/metabolismo , Propionatos/metabolismo , Glicerol/metabolismo , Sacarose/metabolismo , Acetatos/metabolismo , Bactérias , Reatores Biológicos/microbiologia
3.
Braz J Microbiol ; 55(1): 471-485, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38052770

RESUMO

Microorganisms that inhabit the cold Antarctic environment can produce ligninolytic enzymes potentially useful in bioremediation. Our study focused on characterizing Antarctic bacteria and fungi from marine sediment samples of King George and Deception Islands, maritime Antarctica, potentially affected by hydrocarbon influence, able to produce enzymes for use in bioremediation processes in environments impacted with petroleum derivatives. A total of 168 microorganism isolates were obtained: 56 from sediments of King George Island and 112 from Deception Island. Among them, five bacterial isolates were tolerant to cell growth in the presence of diesel oil and gasoline and seven fungal were able to discolor RBBR dye. In addition, 16 isolates (15 bacterial and one fungal) displayed enzymatic emulsifying activities. Two isolates were characterized taxonomically by showing better biotechnological results. Psychrobacter sp. BAD17 and Cladosporium sp. FAR18 showed pyrene tolerance (cell growth of 0.03 g mL-1 and 0.2 g mL-1) and laccase enzymatic activity (0.006 UL-1 and 0.10 UL-1), respectively. Our results indicate that bacteria and fungi living in sediments under potential effect of hydrocarbon pollution may represent a promising alternative to bioremediate cold environments contaminated with polluting compounds derived from petroleum such as polycyclic aromatic hydrocarbons and dyes.


Assuntos
Microbiota , Petróleo , Hidrocarbonetos Policíclicos Aromáticos , Regiões Antárticas , Biodegradação Ambiental , Bioprospecção , Hidrocarbonetos , Gasolina , Sedimentos Geológicos/microbiologia , Bactérias/genética
4.
FEMS Microbiol Ecol ; 99(1)2022 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-36427064

RESUMO

Hydrocarbons may have a natural or anthropogenic origin and serve as a source of carbon and energy for microorganisms in Antarctic soils. Herein, 16S rRNA gene and shotgun sequencing were employed to characterize taxonomic diversity and genetic potential for hydrocarbon degradation of the microbiome from sediments of sites located in two Antarctic islands subjected to different temperatures, geochemical compositions, and levels of presumed anthropogenic impact, named: Crater Lake/Deception Island (pristine area), Whalers Bay and Fumarole Bay/Deception Island (anthropogenic-impacted area), and Hannah Point/Livingston Island (anthropogenic-impacted area). Hydrocarbon concentrations were measured for further correlation analyses with biological data. The majority of the hydrocarbon-degrading genes were affiliated to the most abundant bacterial groups of the microbiome: Proteobacteria and Actinobacteria. KEGG annotation revealed 125 catabolic genes related to aromatic hydrocarbon (styrene, toluene, ethylbenzene, xylene, naphthalene, and polycyclic hydrocarbons) and aliphatic (alkanes and cycloalkanes) pathways. Only aliphatic hydrocarbons, in low concentrations, were detected in all areas, thus not characterizing the areas under study as anthropogenically impacted or nonimpacted. The high richness and abundance of hydrocarbon-degrading genes suggest that the genetic potential of the microbiome from Antarctic sediments for hydrocarbon degradation is driven by natural hydrocarbon occurrence.


Assuntos
Microbiota , Hidrocarbonetos Policíclicos Aromáticos , RNA Ribossômico 16S/genética , Regiões Antárticas , Hidrocarbonetos/metabolismo , Microbiota/genética , Microbiologia do Solo , Bactérias/genética , Bactérias/metabolismo , Biodegradação Ambiental , Ilhas , Hidrocarbonetos Policíclicos Aromáticos/metabolismo
5.
An Acad Bras Cienc ; 94(suppl 1): e20210840, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35384978

RESUMO

Currently, antimicrobial resistance has become a global public health problem, which has made the need for new antimicrobial compounds to deal with resistant infections an emergency. However, environments that once offered so many innovative molecules, now already exhaustively exploited, do not meet this need. In this context, a geographically isolated, under-explored and extreme environment, such as Antarctica, which holds organisms with unique physiological and biochemical characteristics, assumes great importance as a potential source of new compounds with antimicrobial activity. In this patent review, we investigate the state of technological development in the field of antimicrobial compounds obtained from Antarctic organisms, highlighting the main countries and researchers active in the field, the species utilized, the compounds obtained, and their possible therapeutic applications. As results, few patent documents were found, however they encompass a wide diversity of compounds and species, indicating a great antimicrobial potential present in Antarctic biota, including compounds active against the most important human pathogenic microorganisms, such as including methicillin-resistant Staphylococcus aureus, vancomycin-resistant Enterococcus spp. and multi-resistant Mycobacterium tuberculosis. Furthermore, due to the increasing trend in patent applications, a significant rise in the number of patents in this area is expected in the coming years.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Regiões Antárticas , Antibacterianos/farmacologia , Humanos
6.
An Acad Bras Cienc ; 94(suppl 1): e20210459, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35293946

RESUMO

Industrial sectors are searching for new compounds to improve the preservation of food and blood, human tissues, and fuels used at low temperatures. Antarctic microorganisms have mechanisms to overcome injuries caused by low temperatures, making them sources of compounds with antifreeze activity. However, it is mandatory that such compounds do not pose a risk to human health. The present study evaluated the potential of Antarctic bacteria to resist freezing, produce virulence factors, their tolerance to physiological pHs/temperature and resistance to antibiotics. Sixty-five isolates were tested for antifreeze compound production, among which, 31 grew after the test. Of these, 3 strains of Arthrobacter sp. (356, 358 and 443), one Psychromonas arctica (ESH238) and one unidentified strain (363) showed positive results for hemolytic activity. Psychrobacter sp. 456 showed proteinase activity. None of the isolates showed resistance to the antibiotics. All isolates were able to grow in one of the three pHs (4, 7 and 8) and/or temperature (36, 38 and 40 ºC). Antarctic bacterial present potential for the production of antifreeze compounds and may be considered safe in industrial processes. The characterization of the genes responsible for virulence factors should be carried out to reinforce the potential applicability of such bacteria.


Assuntos
Antibacterianos , Arthrobacter , Regiões Antárticas , Arthrobacter/genética , Congelamento , Humanos , Filogenia
7.
An Acad Bras Cienc ; 94(suppl 1): e20210540, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35293947

RESUMO

In the Antarctic environment, yeasts are versatile eukaryotes that have shown wide dispersion in different substrates, producing active enzymes in extreme conditions, but their relevance in biotechnological applications is largely unknown. The aim of this study was to evaluate the production of extracellular hydrolases by yeasts isolated from Antarctic lichens and molecularly identify these isolates. From a total of 144 isolates on the screening, 109 (76%) produced at least one of the hydrolases tested, with most activities for proteases 59 (41%), cellulases 58 (40%), esterases 57 (39%), lipases 29 (20%), amylases 23 (16%) and pectinases 20 (14%). Among these isolates, 76 were identified, most belonged to the phylum Basidiomycota (n=73) with the dominance of Vishniacozyma victoriae (n=27), Cystobasidium alpinum (n=3), Mrakia niccombsii (n=3), Cystobasidium laryngis (n=2), Bannozyma yamatoana (n=2), Holtermanniella nyarrowii (n=2), and Glaciozyma martinii (n=2). This study is the first one reporting extracellular enzyme production by yeasts isolated from thallus of the species of Antarctic lichens Lecania brialmontii, Polycauliona candelaria, Usnea capillacea, Cladonia metacorallifera, and Polycauliona regalis. With these data, it's possible to confirm lichens as a source of hydrolase-producing yeasts, reinforcing the potential of these microorganisms in bioprospecting studies of catalytic molecules from polar regions that may be useful in promising biotechnological applications.


Assuntos
Líquens , Hidrólise , Lipase , Peptídeo Hidrolases , Leveduras
8.
An Acad Bras Cienc ; 94(suppl 1): e20210452, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35170668

RESUMO

Microbial therapeutic enzymes are the protagonists in the pharmacological treatment of different human diseases. The intrinsic enzymatic characteristics, such as high affinity and specificity to the corresponding substrate, enable effective therapies, with minimal adverse effects and complete remission. However, immunogenicity, short half-life, low enzymatic yield, and low selectivity regarding available enzyme drugs are currently the main obstacles to their development and the broad adherence to therapeutic protocols. By harboring adapted and still unexplored microbial life, environments of extreme conditions, such as Antarctica, become especially important in the prospecting and development of new enzymatic compounds that present higher yields and the possibility of genetic improvement. Antarctic microorganisms have adaptation mechanisms, such as more fluid cell membranes, production of antifreeze proteins and enzymes with more malleable structures, more robust, stable, selective catalytic sites for their respective substrates, and high antioxidant capacity. In this context, this review aims to explore enzymes synthesized by bacteria and fungi from Antarctica as potential drug producers, capable of providing therapeutic efficacy, less adverse effects, and lower production costs with highlight to L-Asparaginase, collagenase, superoxide dismutase and ribonucleases. In addition, this review highlights the unique biotechnological profile of these Antarctic extremophile microorganisms.


Assuntos
Bactérias , Fungos , Regiões Antárticas , Humanos
9.
J Manipulative Physiol Ther ; 45(8): 595-603, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37318389

RESUMO

OBJECTIVE: The purpose of this study was to analyze the quality of reporting and presence of spin in abstracts of randomized clinical trials (RCTs) on the use of electroanalgesia for musculoskeletal pain. METHODS: The Physiotherapy Evidence Database (PEDro) was searched from 2010 to June 2021. Inclusion criteria were RCTs using electroanalgesia in individuals with musculoskeletal pain, written in any language, comparing 2 or more groups, and with pain as 1 of the outcomes. Two blinded, independent, and calibrated evaluators (Gwet's AC1 agreement analysis) performed eligibility and data extraction. General characteristics, report of outcomes, quality of reporting (Consolidated Standards of Reporting Trials for Abstracts [CONSORT-A]), and spin analysis (7-item spin checklist and spin analysis per section) were extracted from abstracts. RESULTS: Of 989 studies selected, 173 abstracts were analyzed after screening and eligibility criteria. Mean risk of bias on the PEDro scale was 6.02 ± 1.6 points. Most abstracts did not report significant differences for primary (51.4%) and secondary (63%) outcomes. Mean quality of reporting was 5.10 ± 2.4 points in the CONSORT-A, and spin was 2.97 ± 1.7. Abstracts had at least 1 type of spin (93%), and the conclusion presented the greatest number of spin types. More than 50% of abstracts recommended an intervention without significant differences between groups. CONCLUSION: This study found that the majority of RCT abstracts on electroanalgesia for musculoskeletal conditions in our sample had a moderate to high risk of bias, incomplete or missing information, and some type of spin. We recommend that health care providers who use electroanalgesia and the scientific community be aware of spin in published studies.


Assuntos
Medicina , Dor Musculoesquelética , Estimulação Elétrica Nervosa Transcutânea , Humanos , Dor Musculoesquelética/diagnóstico , Dor Musculoesquelética/terapia , Modalidades de Fisioterapia , Lista de Checagem , Ensaios Clínicos Controlados Aleatórios como Assunto
10.
Microorganisms ; 9(9)2021 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-34576708

RESUMO

Microorganisms inhabiting subsurface petroleum reservoirs are key players in biochemical transformations. The interactions of microbial communities in these environments are highly complex and still poorly understood. This work aimed to assess publicly available metagenomes from oil reservoirs and implement a robust pipeline of genome-resolved metagenomics to decipher metabolic and taxonomic profiles of petroleum reservoirs worldwide. Analysis of 301.2 Gb of metagenomic information derived from heavily flooded petroleum reservoirs in China and Alaska to non-flooded petroleum reservoirs in Brazil enabled us to reconstruct 148 metagenome-assembled genomes (MAGs) of high and medium quality. At the phylum level, 74% of MAGs belonged to bacteria and 26% to archaea. The profiles of these MAGs were related to the physicochemical parameters and recovery management applied. The analysis of the potential functional core in the reservoirs showed that the microbiota was specialized for each site, with 31.7% of the total KEGG orthologies annotated as functions (1690 genes) common to all oil fields, while 18% of the functions were site-specific, i.e., present only in one of the oil fields. The oil reservoirs with a lower level of intervention were the most similar to the potential functional core, while the oil fields with a long history of water injection had greater variation in functional profile. These results show how key microorganisms and their functions respond to the distinct physicochemical parameters and interventions of the oil field operations such as water injection and expand the knowledge of biogeochemical transformations in these ecosystems.

11.
Front Microbiol ; 10: 648, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31024471

RESUMO

Drylands occupy approximately 41% of the Earth's terrestrial surface. Climate change and land use practices are expected to affect biogeochemical cycling by the soil microbiome in these ecosystems. Understanding how soil microbial community might respond to these drivers is extremely important to mitigate the processes of land degradation and desertification. The Caatinga, an exclusively Brazilian biome composed of an extensive seasonal tropical dry forest, is exposed to variable spatiotemporal rainfall patterns as well as strong human-driven pressures. Herein, an integrated analysis of shotgun metagenomics approach coupled to meteorological data was employed to unravel the impact of seasonality and land use change on soil microbiome from preserved and agriculture-affected experimental fields in Caatinga drylands. Multivariate analysis suggested that microbial communities of preserved soils under seasonal changes were shaped primarily by water deficit, with a strong increase of Actinobacteria and Proteobacteria members in the dry and rainy seasons, respectively. In contrast, nutrient availability notably played a critical role in driving the microbial community in agriculture-affected soils. The strong enrichment of bacterial genera belonging to the poorly-known phylum Acidobacteria ('Candidatus Solibacter' and 'Candidatus Koribacter') in soils from dry season affected by ferti-irrigation practices presupposes a contrasting copiotrophic lifestyle and ecological role in mitigating the impact of chemical fertilization. Functional analyses identify overrepresented genes related to osmotic stress response (synthesis of osmoprotectant compounds, accumulation of potassium ions) and preferential carbon and nitrogen utilization when comparing the microbiome of preserved soils under seasonal changes, reflecting differences in the genetic potential for nutrient cycling and C acquisition in the environment. However, the prevalence of nitrosative stress and denitrification functions in irrigation/fertilization-affected soils of the dry season clearly suggest that nutrient input and disruption of natural water regime may impact biogeochemical cycles linked to the microbial processes, with potential impacts on the ecosystem functionality. These findings help to better understand how natural seasonality and agricultural management differentially affect soil microbial ecology from dry forests, providing support for the development of more sustainable land management in dryland ecosystems.

12.
Mar Biotechnol (NY) ; 21(3): 416-429, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30874930

RESUMO

Considering the global trend in the search for alternative natural compounds with antioxidant and sun protection factor (SPF) boosting properties, bacterial carotenoids represent an opportunity for exploring pigments of natural origin which possess high antioxidant activity, lower toxicity, no residues, and no environmental risk and are readily decomposable. In this work, three pigmented bacteria from the Antarctic continent, named Arthrobacter agilis 50cyt, Zobellia laminarie 465, and Arthrobacter psychrochitiniphilus 366, were able to withstand UV-B and UV-C radiation. The pigments were extracted and tested for UV absorption, antioxidant capacity, photostability, and phototoxicity profile in murine fibroblasts (3T3 NRU PT-OECD TG 432) to evaluate their further potential use as UV filters. Furthermore, the pigments were identified by ultra-high-performance liquid chromatography-photodiode array detector-mass spectrometry (UPLC-PDA-MS/MS). The results showed that all pigments presented a very high antioxidant activity and good stability under exposure to UV light. However, except for a fraction of the A. agilis 50cyt pigment, they were shown to be phototoxic. A total of 18 different carotenoids were identified from 23 that were separated on a C18 column. The C50 carotenes bacterioruberin and decaprenoxanthin (including its variations) were confirmed for A. agilis 50cyt and A. psychrochitiniphilus 366, respectively. All-trans-bacterioruberin was identified as the pigment that did not express phototoxic activity in the 3T3 NRU PT assay (MPE < 0.1). Zeaxanthin, ß-cryptoxanthin, ß-carotene, and phytoene were detected in Z. laminarie 465. In conclusion, carotenoids identified in this work from Antarctic bacteria open perspectives for their further biotechnological application towards a more sustainable and environmentally friendly way of pigment exploitation.


Assuntos
Arthrobacter/química , Biotecnologia , Flavobacteriaceae/química , Pigmentos Biológicos/química , Regiões Antárticas , Carotenoides/química , Carotenoides/isolamento & purificação , Microbiologia Industrial , Pigmentos Biológicos/isolamento & purificação
13.
Sci Total Environ ; 649: 482-494, 2019 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-30176460

RESUMO

Three distinct biological reactors fed with synthetic medium (UASB_Control), synthetic medium and linear alkylbenzene sulfonate (LAS; UASB_SL), and real laundry wastewater (UASB_LW) were compared using a metatranscriptomic approach to determine putative bioindicator genes and taxonomies associated to all steps of anaerobic LAS biodegradation pathway. A homemade bioinformatics pipeline combined with an R workflow was developed to perform the RNAseq data analysis. UASB_SL and UASB_LW showed similar values of LAS biological degradation (~47%) and removal (53-55%). Rarefaction analysis revealed that 1-2 million reads were sufficient to access the whole functional capacity. In the first step of LAS biodegradation pathway, fumarate reductase subunit C was detected and taxonomically assigned to the genus Syntrophobacter (0.002% - UASB_SL; 0.0015% - UASB_LW; not detected - UASB_Control). In the second step, many enzymes related to beta-oxidation were observed and most of them with low relative abundance in UASB Control and taxonomically related with Smithella, Acinetobacter and Syntrophorhabdus. For the ring cleavage step, the abundance of 6 OCH CoA hydrolase putative gene was ten times higher in UASB_SL and UASB_LW when compared to UASB_Control, and assigned to Desulfomonile and Syntrophorhabdus. Finally, the adenylylsulfate reductase, taxonomically related with Desulfovibrio and Desulfomonile, was observed in the desulfonation step with the highest relative abundance in UASB_LW.


Assuntos
Ácidos Alcanossulfônicos/análise , Bactérias/genética , Reatores Biológicos/microbiologia , Tensoativos/metabolismo , Transcriptoma , Águas Residuárias/análise , Poluentes Químicos da Água/análise , Bactérias/metabolismo , Biodegradação Ambiental , Eliminação de Resíduos Líquidos
14.
Antonie Van Leeuwenhoek ; 112(3): 479-490, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30302647

RESUMO

An iridescent yellow pigmented bacterium isolated from the Antarctic continent, named Cellulophaga fucicola strain 416, was found to be able to tolerate UV-B radiation. Its crude pigment extract was tested for antioxidant capacity, UV light stability and phototoxicity profile against murine fibroblast lines. The pigments were further isolated and chemically identified by ultra-high-performance liquid chromatography with photodiode array and mass spectrometry detectors. The results showed that the pigment extract presented weak stability under exposure to UV light, a phototoxic profile in the 3t3 Neutral Red Uptake test and a very high antioxidant activity, suggesting that it could be used as food and feed colourants. Zeaxanthin and two isomers of zeaxanthin, ß-cryptoxanthin and ß-carotene, were identified using a C18 column. These five carotenoids were the major pigments isolated from C. fucicola 416. In conclusion, the identification of pigments produced by the bacterial strain under study may help us understand how bacteria thrive in high UV and cold environments, and opens avenues for further biotechnological application towards a more sustainable and environmentally friendly way of pigment exploitation.


Assuntos
Antioxidantes/análise , Carotenoides/análise , Flavobacteriaceae/química , Flavobacteriaceae/isolamento & purificação , Pigmentos Biológicos/análise , Animais , Regiões Antárticas , Antioxidantes/química , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Carotenoides/química , Carotenoides/isolamento & purificação , Carotenoides/farmacologia , Linhagem Celular , Cromatografia Líquida de Alta Pressão , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Flavobacteriaceae/efeitos da radiação , Espectrometria de Massas , Camundongos , Pigmentos Biológicos/química , Pigmentos Biológicos/isolamento & purificação , Pigmentos Biológicos/farmacologia , Raios Ultravioleta
15.
Syst Appl Microbiol ; 41(5): 473-486, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29759899

RESUMO

Oil refineries are known for the large volume of water used in their processes, as well as the amount of wastewater generated at the end of the production chain. Due to strict environmental regulations, the recycling of water has now become a viable alternative for refineries. Among the many methods available to treat wastewater for reuse, the use of membranes in reverse osmosis systems stands out due to several economic and environmental benefits. However, these systems are vulnerable to contamination and deposition of microorganisms, mainly because of the feedwater quality. In this study, the microbial diversity of feedwater and reverse osmosis membranes was investigated using a combination of culture-dependent and culture-independent methods in order to characterize the microorganisms colonizing and deteriorating the membranes. In total, 37 bacterial isolates, 17 filamentous fungi and approximately 400 clones were obtained and analyzed. Among the bacterial genera identified, the most represented were Sphingobium, Acidovorax, Microbacterium, Rhizobium and Shinella. The results revealed genera that acted as candidate key players in initial biofilm formation in membrane systems, and provided important information concerning the microbial ecology of oligotrophic aquatic systems.


Assuntos
Bactérias/classificação , Biodiversidade , Fungos/classificação , Consórcios Microbianos , Indústria de Petróleo e Gás , Águas Residuárias/microbiologia , Purificação da Água/métodos , Bactérias/genética , Bactérias/isolamento & purificação , Fenômenos Fisiológicos Bacterianos , Biofilmes/crescimento & desenvolvimento , Brasil , Fungos/genética , Fungos/isolamento & purificação , Fungos/fisiologia , Metagenômica , Osmose
16.
Glob Chang Biol ; 24(7): 3170-3186, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29485732

RESUMO

Warming is among the major drivers of changes in biotic interactions and, in turn, ecosystem functioning. The decomposition process occurs in a chain of facilitative interactions between detritivores and microorganisms. It remains unclear, however, what effect warming may have on the interrelations between detritivores and microorganisms, and the consequences for the functioning of natural freshwater ecosystems. To address these gaps, we performed a field experiment using tank bromeliads and their associated aquatic fauna. We manipulated the presence of bacteria and detritivorous macroinvertebrates (control, "bacteria," and "bacteria + macroinvertebrates") under ambient and warming scenarios, and analyzed the effects on the microorganisms and ecosystem functioning (detritus mass loss, colored dissolved organic matter, and nitrogen flux). We applied antibiotic solution to eliminate or reduce bacteria from control bromeliads. After 60 days incubation, bacterial density was higher in the presence than in the absence of macroinvertebrates. In the absence of macroinvertebrates, temperature did not influence bacterial density. However, in the presence of macroinvertebrates, bacterial density decreased by 54% with warming. The magnitude of the effects of organisms on ecosystem functioning was higher in the combined presence of bacteria and macroinvertebrates. However, warming reduced the overall positive effects of detritivores on bacterial density, which in turn, cascaded down to ecosystem functioning by decreasing decomposition and nitrogen flux. These results show the existence of facilitative mechanisms between bacteria and detritivores in the decomposition process, which might collapse due to warming. Detritivores seem to contribute to nutrient cycling as they facilitate bacterial populations, probably by increasing nutrient input (feces) in the ecosystem. However, increased temperature mitigated these beneficial effects. Our results add to a growing research body that shows that warming can affect the structure of aquatic communities, and highlight the importance of considering the interactive effects between facilitation and climatic drivers on the functioning of freshwater ecosystems.


Assuntos
Organismos Aquáticos/fisiologia , Ecossistema , Água Doce , Temperatura Alta , Animais , Organismos Aquáticos/metabolismo , Bactérias/metabolismo , Invertebrados/metabolismo , Nitrogênio/metabolismo , Dinâmica Populacional
17.
Microbiologyopen ; 6(4)2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28544594

RESUMO

Aromatic hydrocarbons (AH), such as polycyclic aromatic hydrocarbons, are compounds largely found in nature. Aromatic-ring-hydroxylating dioxygenases (ARHD) are proteins involved in AH degradation pathways. We used ARHD functional genes from an oil-impacted mangrove area and compared their diversity with other sites around the world to understand the ARHD biogeographic distribution patterns. For this, a comprehensive database was established with 166 operational protein families (OPFs) from 1,758 gene sequences obtained from 15 different sites worldwide, of which twelve are already published studies and three are unpublished. Based on a deduced ARHD peptide sequences consensus phylogeny, we examined trends and divergences in the sequence phylogenetic clustering from the different sites. The taxonomic affiliation of the OPF revealed that Pseudomonas, Streptomyces, Variovorax, Bordetella and Rhodococcus were the five most abundant genera, considering all sites. The functional diversity analysis showed the enzymatic prevalence of benzene 1,2-dioxygenase, 3-phenylpropionate dioxygenase and naphthalene 1,2-dioxygenase, in addition to 10.98% of undefined category ARHDs. The ARHD gene correlation analysis among different sites was essentially important to gain insights on spatial distribution patterns, genetic congruence and ecological coherence of the bacterial groups found. This work revealed the genetic potential from the mangrove sediment for AH biodegradation and a considerable evolutionary proximity among the dioxygenase OPFs found in Antarctica and South America sites, in addition to high level of endemism in each continental region.


Assuntos
Bactérias/enzimologia , Dioxigenases/genética , Variação Genética , Hidrocarbonetos Aromáticos/metabolismo , Microbiota , Filogeografia , Plantas/microbiologia , Bactérias/classificação , Dioxigenases/metabolismo , Áreas Alagadas
18.
Braz J Phys Ther ; 21(2): 107-113, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28460708

RESUMO

BACKGROUND: Sports that require the constant use of an upper limb demand the maximum kinetic chain efficiency in this segment. Immaturity of the musculoskeletal system, followed by failure in motor skills can expose adolescents to major reports of pain complaints, particularly for the shoulder. OBJECTIVE: To evaluate the prevalence of shoulder pain in adolescent athletes and identify possible factors associated with the complaint. METHOD: A total of 310 athletes, of both sexes and aged between 10 and 19 years old participated on this study. The subjects filled out a questionnaire with personal, sports and upper limb function (Quick-DASH) questions. We evaluated the height, body mass, shoulder rotation range and stability of the upper limb using the CKCUES-test. The association between pain and the variables was analyzed using multilevel modeling logistic regression. We used the Mann-Whitney test for comparing between pain and function. RESULTS: The prevalence of shoulder pain was 43.5%. Athletes between 15 and 19 years, handball and judo practitioners, are 1.86, 2.14 and 3.07 more likely to report shoulder pain, respectively, when compared with other sports and ages. Shoulder pain reduced function scores (p<0.001) and increased changes in the range of motion (p<0.04). CONCLUSION: Shoulder pain is highly prevalent and is associated especially with older adolescent athletes of handball and judo, and affects the levels of function and the range of the shoulder.


Assuntos
Traumatismos em Atletas/epidemiologia , Dor de Ombro/fisiopatologia , Ombro/fisiopatologia , Extremidade Superior/fisiopatologia , Atletas , Humanos , Prevalência , Amplitude de Movimento Articular , Inquéritos e Questionários
19.
J. pediatr. (Rio J.) ; 93(2): 200-206, Mar.-Apr. 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-841332

RESUMO

Abstract Objective: To evaluate the reliability and validity of the Brazilian version of the Pittsburgh Sleep Quality Index. Methods: 309 adolescents, subdivided into a sample of 209 subjects, of whom 25 were reassessed, and another sample of 100 adolescents. Reliability was assessed using Cronbach's α-values, intraclass correlation coefficient, Standard Error of Measure, Minimum Detectable Change, and Bland-Altman plotting. Exploratory analysis of the questionnaire components was performed based on the sample of 209 adolescents. Confirmatory factor analysis was performed with a sample of 100 individuals. Results: The sample of 209 participants had a mean age of 14.38 (±1.94) years, comprising 80 (38.3%) girls and 129 (61.7%) boys. The sample of 100 adolescents had a mean age of 13.66 (±2.35) years, comprising 51 (51%) girls and 49 (49%) boys. The questionnaire obtained a Standard Error of Measure = 1.12 and Minimum Detectable Change = 3.10. Cronbach's α was 0.71 and the Intraclass Correlation Coefficient was 0.65 (95% CI: 0.21-0.85). The factor analysis showed that the best model of components was the one that consisted of two factors, excluding the component on the use of sleep medications. Conclusion: The questionnaire showed high internal consistency and moderate reliability. Furthermore, a model with two factors seems to be the most appropriate to evaluate the quality of sleep in adolescents.


Resumo Objetivo: Avaliar a confiabilidade e validade da versão brasileira do Índice de Qualidade do Sono de Pittsburgh. Métodos: Uma amostra de 309 adolescentes, subdivididos em uma de 209 indivíduos, dos quais 25 foram reavaliados, e outra de 100 adolescentes. A confiabilidade foi avaliada por meio dos valores de α de Cronbach, coeficiente de correlação intraclasse, erro padrão da medida, mínima mudança detectável e plotado gráfico Bland-Altman. A análise exploratória dos componentes do questionário foi feita com base na amostra de 209 adolescentes. A análise fatorial confirmatória foi feita com a amostra de 100 indivíduos. Resultados: A amostra de 209 participantes teve uma média de 14,38 (± 1,94) anos, 80 (38,3%) meninas e 129 (61,7%) meninos. A amostra composta por 100 adolescentes teve uma média de 13,66 (± 2,35) anos, 51 (51%) meninas e 49 (49%) meninos. O questionário obteve erro padrão da medida = 1,12 e mudança mínima detectável = 3,10. O α de Cronbach foi de 0,71 e coeficiente de correlação intraclasse de 0,65 (IC95% 0,21-0,85). As análises fatoriais apontaram como melhor modelo de componentes aquele composto por dois fatores, com exclusão do componente sobre uso de medicamentos para dormir. Conclusão: O questionário obteve elevada consistência interna e confiabilidade moderada. Além disso, um modelo de dois fatores parece ser o mais adequado para avaliar a qualidade do sono em adolescentes.


Assuntos
Humanos , Masculino , Feminino , Criança , Adolescente , Adulto , Adulto Jovem , Inquéritos e Questionários , Distúrbios do Início e da Manutenção do Sono/diagnóstico , Qualidade de Vida , Sono , Brasil , Reprodutibilidade dos Testes , Análise Fatorial
20.
Int J Sports Phys Ther ; 12(1): 125-132, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28217423

RESUMO

BACKGROUND: The Closed Kinetic Chain Upper Extremity Stability Test (CKCUEST) has been proposed as an option to assess upper limb function and stability; however, there are few studies that support the use of this test in adolescents. PURPOSE: The purpose of the present study was to investigate the intersession reliability and agreement of three CKCUEST scores in adolescents and establish clinimetric values for this test. STUDY DESIGN: Test-retest reliability. METHODS: Twenty-five healthy adolescents of both sexes were evaluated. The subjects performed two CKCUEST with an interval of one week between the tests. An intraclass correlation coefficient (ICC3,3) two-way mixed model with a 95% interval of confidence was utilized to determine intersession reliability. A Bland-Altman graph was plotted to analyze the agreement between assessments. The presence of systematic error was evaluated by a one-sample t test. The difference between the evaluation and reevaluation was observed using a paired-sample t test. The level of significance was set at 0.05. Standard error of measurements and minimum detectable changes were calculated. RESULTS: The intersession reliability of the average touches score, normalized score, and power score were 0.68, 0.68 and 0.87, the standard error of measurement were 2.17, 1.35 and 6.49, and the minimal detectable change was 6.01, 3.74 and 17.98, respectively. The presence of systematic error (p < 0.014), the significant difference between the measurements (p < 0.05), and the analysis of the Bland-Altman graph infer that CKCUEST is a discordant test with moderate to excellent reliability when used with adolescents. CONCLUSION: The CKCUEST is a measurement with moderate to excellent reliability for adolescents. LEVEL OF EVIDENCE: 2b.

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