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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.
High Alt Med Biol ; 23(4): 352-360, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36472463

RESUMO

Mundo, William, Lilian Toledo-Jaldin, Alexandrea Heath-Freudenthal, Jaime Huayacho, Litzi Lazo-Vega, Alison Larrea-Alvarado, Valquiria Miranda-Garrido, Rodrigo Mizutani, Lorna G. Moore, Any Moreno-Aramayo, Richard Gomez, Patricio Gutierrez, and Colleen G. Julian. Is maternal cardiovascular performance impaired in altitude-associated fetal growth restriction? High Alt Med Biol. 23:352-360, 2022. Introduction: The incidence of fetal growth restriction (FGR) is elevated in high-altitude resident populations. This study aims to determine whether maternal central hemodynamics during the last trimester of pregnancy are altered in high-altitude FGR. Methods: In this cross-sectional study of maternal-infant pairs (FGR, n = 27; controls, n = 26) residing in La Paz, Bolivia, maternal heart rate, cardiac output (CO), stroke volume, and systemic vascular resistance (SVR) were assessed using continuous-wave Doppler ultrasound. Transabdominal Doppler ultrasound was used for uterine artery (UtA) resistance indices and fetal measures. Maternal venous soluble fms-like tyrosine kinase-1 (sFlt1) levels were measured. Results: FGR pregnancies had reduced CO, elevated SVR and UtA resistance, fetal brain sparing, and increased maternal sFlt1 versus controls. Maternal SVR was positively associated with UtA resistance and inversely associated with middle cerebral artery resistance and birth weight. Maternal sFlt1 was greater in FGR than controls and positively associated with UtA pulsatility index. Women with elevated sFlt1 levels also tended to have lower CO and higher SVR. Conclusion: Noninvasive assessment of maternal cardiovascular function may be an additional method for detecting high-risk pregnancies at high altitudes, thereby informing the need for increased surveillance and appropriate allocation of resources to minimize adverse outcomes.


Assuntos
Retardo do Crescimento Fetal , Receptor 1 de Fatores de Crescimento do Endotélio Vascular , Gravidez , Feminino , Humanos , Retardo do Crescimento Fetal/etiologia , Retardo do Crescimento Fetal/diagnóstico , Altitude , Estudos Transversais
5.
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
6.
Pregnancy Hypertens ; 16: 139-144, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31056149

RESUMO

The goals of the United Nation's Millennium Summit for reducing maternal mortality have proven difficult to achieve. In Bolivia, where maternal mortality is twice the South American average, improving the diagnosis, treatment and ultimately prevention of preeclampsia is key for achieving targeted reductions. We held a workshop in La Paz, Bolivia to review recent revisions in the diagnosis and treatment of preeclampsia, barriers for their implementation, and means for overcoming them. While physicians are generally aware of current recommendations, substantial barriers exist for their implementation due to geographic factors increasing disease prevalence and limiting health-care access, cultural and economic factors affecting the care provided, and infrastructure deficits impeding diagnosis and treatment. Means for overcoming such barriers include changes in the culture of health care, use of standardized diagnostic protocols, the adoption of low-cost technologies for improving the diagnosis and referral of preeclamptic cases to specialized treatment centers, training programs to foster multidisciplinary team approaches, and efforts to enhance local research capacity. While challenging, the synergistic nature of current barriers for preeclampsia diagnosis and treatment also affords opportunities for making far-reaching improvements in maternal, infant and lifelong health.


Assuntos
Acessibilidade aos Serviços de Saúde/organização & administração , Serviços de Saúde Materna/organização & administração , Pré-Eclâmpsia/epidemiologia , Bolívia/epidemiologia , Feminino , Humanos , Pré-Eclâmpsia/mortalidade , Pré-Eclâmpsia/prevenção & controle , Gravidez
7.
Santiago; Ministerio de Salud; 1991. 26 p. ilus.
Monografia em Espanhol | LILACS | ID: lil-132583
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