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1.
Environ Microbiol Rep ; 16(2): e13245, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38643985

RESUMO

Cueva del Viento, located in the Canary Islands, Spain, is the Earth's sixth-longest lava tube, spanning 18,500 m, and was formed approximately 27,000 years ago. This complex volcanic cave system is characterized by a unique geomorphology, featuring an intricate network of galleries. Despite its geological significance, the geomicrobiology of Cueva del Viento remains largely unexplored. This study employed a combination of culture-dependent techniques and metabarcoding data analysis to gain a comprehensive understanding of the cave's microbial diversity. The 16S rRNA gene metabarcoding approach revealed that the coloured microbial mats (yellow, red and white) coating the cave walls are dominated by the phyla Actinomycetota, Pseudomonadota and Acidobacteriota. Of particular interest is the high relative abundance of the genus Crossiella, which is involved in urease-mediated biomineralization processes, along with the presence of genera associated with nitrogen cycling, such as Nitrospira. Culture-dependent techniques provided insights into the morphological characteristics of the isolated species and their potential metabolic activities, particularly for the strains Streptomyces spp., Paenarthrobacter sp. and Pseudomonas spp. Our findings underscore the potential of Cueva del Viento as an ideal environment for studying microbial diversity and for the isolation and characterization of novel bacterial species of biotechnological interest.


Assuntos
Cavernas , Filogenia , RNA Ribossômico 16S , Espanha , Cavernas/microbiologia , RNA Ribossômico 16S/genética , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , DNA Bacteriano/genética , Biodiversidade
3.
Sci Total Environ ; 913: 169583, 2024 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-38154629

RESUMO

Lanzarote (Canary Islands, Spain) is one of the best terrestrial analogs to Martian volcanology. Particularly, Lanzarote lava tubes may offer access to recognizably preserved chemical and morphological biosignatures valuable for astrobiology. By combining microbiological, mineralogical, and organic geochemistry tools, an in-depth characterization of speleothems and associated microbial communities in lava tubes of Lanzarote is provided. The aim is to untangle the underlying factors influencing microbial colonization in Earth's subsurface to gain insight into the possibility of similar subsurface microbial habitats on Mars and to identify biosignatures preserved in lava tubes unequivocally. The microbial communities with relevant representativeness comprise chemoorganotrophic, halophiles, and/or halotolerant bacteria that have evolved as a result of the surrounding oceanic environmental conditions. Many of these bacteria have a fundamental role in reshaping cave deposits due to their carbonatogenic ability, leaving behind an organic record that can provide evidence of past or present life. Based on functional profiling, we infer that Crossiella is involved in fluorapatite precipitation via urea hydrolysis and propose its Ca-rich precipitates as compelling biosignatures valuable for astrobiology. In this sense, analytical pyrolysis, stable isotope analysis, and chemometrics were conducted to characterize the complex organic fraction preserved in the speleothems and find relationships among organic families, microbial taxa, and precipitated minerals. We relate organic compounds with subsurface microbial taxa, showing that organic families drive the microbiota of Lanzarote lava tubes. Our data indicate that bacterial communities are important contributors to biomarker records in volcanic-hosted speleothems. Within them, the lipid fraction primarily consists of low molecular weight n-alkanes, α-alkenes, and branched-alkenes, providing further evidence that microorganisms serve as the origin of organic matter in these formations. The ongoing research in Lanzarote's lava tubes will help develop protocols, routines, and predictive models that could provide guidance on choosing locations and methodologies for searching potential biosignatures on Mars.


Assuntos
Marte , Microbiota , Humanos , Meio Ambiente Extraterreno , Minerais , Alcenos
4.
Artigo em Inglês | MEDLINE | ID: mdl-34388083

RESUMO

A novel facultatively anaerobic, non-motile, Gram-stain-negative, non-endospore-forming alphaproteobacterium, strain 1011MAR3C25T, was isolated from a white biofilm colonizing the walls of the Andalusian show cave Gruta de las Maravillas (Huelva, Spain). Strain 1011MAR3C25T grew at 8-42 °C (optimum, 20-30 °C), at pH 5.0-9.0 (optimum, pH 5.0-6.0) and in the presence of 0-12 % (w/v) NaCl (optimum 3-5 %). Cells were catalase- and oxidase-positive. The strain grew heterotrophically with various carbon sources and chemoautotrophically with thiosulfate under aerobic conditions. Results of phylogenetic analysis showed that strain 1011MAR3C25T was related to Paracoccus saliphilus DSM 18447T and Paracoccus alkanivorans LMG 30882T (97.90 % and 97.32 % 16S rRNA sequence identity values, respectively). The major respiratory quinone was ubiquinone Q-10 and the predominant fatty acid was C18 : 1 ω7c. The polar lipid profile consisted of diphosphatidylglycerol, phosphatidylcholine, phosphatidylglycerol, an unidentified aminolipid, an unidentified glycolipid and an unidentified polar lipid. The DNA G+C content was 60.3 mol%. Based on a polyphasic taxonomic study it is proposed that strain 1011MAR3C25T (=CECT 9092T=LMG 29414T) represents a novel species of the genus Paracoccus, for which the name Paracoccus onubensis sp. nov. is proposed.


Assuntos
Cavernas/microbiologia , Paracoccus , Filogenia , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Hibridização de Ácido Nucleico , Paracoccus/classificação , Paracoccus/isolamento & purificação , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Espanha , Ubiquinona/análogos & derivados , Ubiquinona/química
5.
Rev. bras. oftalmol ; 74(4): 216-221, Jul-Aug/2015. tab, graf
Artigo em Português | LILACS | ID: lil-752066

RESUMO

Objetivo: Avaliar o impacto da degeneração macular relacionada à idade (DMRI) na qualidade de vida relacionada com a visão (QVRV) numa amostra de pacientes portugueses. Métodos: Estudo observacional em corte transversal, não comparativo no qual foram incluídos 68 pacientes seguidos no departamento de Retina Médica do Serviço de Oftalmologia do Centro Hospitalar de Lisboa Ocidental, entre janeiro e abril de 2011. A QVRV foi avaliada por meio do questionário National Eye Institute Visual Functioning Questionnaire (NEI-VFQ-25), traduzido para o português. Os scores obtidos foram analisados e correlacionados com os seguintes parâmetros idade, sexo, lateralidade da doença, tempo de follow-up, acuidade visual (AV) e EFC iniciais e finais do melhor (MO) e pior olho (PO). Resultados: A AV do PO apresentou valor preditivo nos scores global, atividade para longe, visão cromática, visão periférica, desempenho, função social e saúde mental (p<0,05). Num modelo de multivariáveis com inclusão de todos os parâmetros clínicos analisados, as variáveis estudadas explicaram 60% da variância do score global (SG) com um valor preditivo de 0,08 (R2 0,57, p=0,088). Conclusões: A DMRI NV está associada a uma diminuição da QVRV. A AV do PO tem valor preditivo nos scores do NEI-VFQ-25.


Purpose: To describe the impact of aged-related macular degeneration (AMD) on vision-related quality of life (QOL) on a sample of portuguese patients and explore the association with vision, Central Foveal Thickness (CFT) and demographic variables in a Portuguese population. Methods: Observational, interview study of 68 patients with clinical diagnosis of NV AMD seen between January and April 2011 at the Ophthalmology Department of Centro Hospitalar de Lisboa Ocidental. Health-related quality of life (HRQL) was measured with a Portuguese version of the 25-item National Eye Institute Visual Function Questionnaire (NEI VFQ-25). Scores were analysed and correlated with age, gender, laterality of the disease, initial and final visual acuity (VA), CFT and duration of follow-up. Results: Worst eye VA had predictive value in the following scores: global, distance activities, color vision, peripheral vision, role difficulties, social functioning and mental health (p<0.05). In a multivariable model with inclusion of all the parameters studied, the analysed variables explained 60% of the variability of the Global Score, with a predictive value of 0.08 (R2 0.57, p=0.088). Conclusion: NV AMD is associated with impairment in reported vision related QOL in our group of patients. The VA of the worst eye has a predictive value in NEI VFQ-25 scores.


Assuntos
Humanos , Masculino , Feminino , Idoso , Idoso de 80 Anos ou mais , Doença Crônica , Degeneração Macular , Qualidade de Vida , Inquéritos e Questionários , Acuidade Visual , Estudos Transversais , Estudo Observacional , Portugal
6.
Rev. bras. oftalmol ; 73(4): 230-236, Jul-Aug/2014. tab, graf
Artigo em Português | LILACS | ID: lil-730582

RESUMO

Objetivo: Determinar se existe variação da PIO em doentes com glaucoma submetidos à cirurgia de catarata. Métodos: Estudo retrospectivo de 101 olhos, de 75 doentes com média de idade de 78,91 ± 7,9 anos submetidos à cirurgia de catarata por facoemulsificação por dois cirurgiões, sem complicações associadas e com follow-up superior a 6 meses. Os olhos foram subdivididos em dois grupos: olhos com glaucoma (G) e olhos sem glaucoma (SG). A PIO foi avaliada por tonometria de Goldmann. Resultados: Analisaram-se 51 olhos do grupo (SG) e 50 olhos do grupo (G). A PIO média nos dois grupos era no pré-operatório 16,08 ± 3,04, sendo aos 12 meses 14,69 ± 2,7 e aos 24 meses 14,21 ± 3,56. A diminuição média de PIO do pré-operatório para os 12 meses foi de 1,49 ± 2,98. A PIO pré-operatória apresentou uma diferença com significado estatístico da PIO aos 12 e 24 meses (p<0,001 e p=0,001, respectivamente T. t pares) na amostra global. Não se detectou uma diferença com significado estatístico na variação de PIO entre estes 2 grupos de olhos (p>0,05, teste T Student). Determinou-se um modelo de regressão linear stepwise para a variação de PIO do pré-operatório para os 12m. As variáveis com valor preditivo eram a PIO pré-operatória (R2=0,249, p=0,03), e a idade (R2=0,18, p=0,01). Conclusão: O nosso estudo revela que a cirurgia de catarata por facoemulsificação leva a uma diminuição significativa da PIO, que se mantém aos 12 e 24m. .


Objective: To describe the variation of intraocular pressure (IOP) in patients with glaucoma submitted to cataract surgery. Methods: Retrospective study of 101 eyes of 75 patients with medium age of 78.91 ± 7.9 submitted to cataract surgery by facoemulsification by two surgeons, without complications and with at least 6 months of follow-up. The eyes were divided in two groups: eyes with glaucoma (G) and eyes without glaucoma (NG). The IOP was evaluated with Goldmann tonometry. Results: 51 eyes without glaucoma and 50 eyes with glaucoma. The medium IOP was 16.08 ± 3.04 before surgery, 14.69 ± 2.7 at 12 months and 14.21 ± 3.56 at 24 months. The medium value of IOP reduction before surgery to 12 months was 1.49 ± 2.98. IOP measured before surgery differed statistically from IOP at 12 and 24 months (p<0.001 e p=0.001 respectively, T. Student). Between the two groups of eyes there wasn’t a statistically significant difference in the variation of IOP (p>0.05, T Student). A model of linear regression stepwise was calculated for the variation of the IOP from before surgery to 12 months. The variables with more predictive value were IOP before surgery (R2=0.249, p=0.03) and age (R2=0.18, p=0.01). Conclusion: In our study cataract surgery results in IOP reduction, that is maintained at 12 months. .


Assuntos
Humanos , Masculino , Feminino , Idoso , Extração de Catarata/métodos , Facoemulsificação/métodos , Pressão Intraocular/fisiologia , Tonometria Ocular , Acuidade Visual , Glaucoma/fisiopatologia , Valor Preditivo dos Testes , Estudos Retrospectivos , Seguimentos , Implante de Lente Intraocular , Comprimento Axial do Olho
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