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1.
Microorganisms ; 12(6)2024 May 24.
Article de Anglais | MEDLINE | ID: mdl-38930448

RÉSUMÉ

Hot springs worldwide can be a source of extremophilic microorganisms of biotechnological interest. In this study, samplings of a hot spring in Hidalgo, Mexico, were conducted to isolate, identify, and characterize morphologically, biochemically, and molecularly those bacterial strains with potential industrial applications. In addition, a physicochemical and geochemical examination of the hot spring was conducted to fully understand the study region and its potential connection to the strains discovered. The hot spring was classified as sulfate-calcic according to the Piper Diagram; the hydrogeochemical analysis showed the possible interactions between minerals and water. Eighteen bacterial strains were isolated with optimal growth temperatures from 50 to 55 °C. All strains are Gram-positive, the majority having a rod shape, and one a round shape, and 17 produce endospores. Hydrolysis tests on cellulose, pectin, and xylan agar plates demonstrated enzymatic activity in some of the strains. Molecular identification through the 16S rDNA gene allowed classification of 17 strains within the Phylum Firmicutes and one within Deinococcus-Thermus. The bacterial strains were associated with the genera Anoxybacillus, Bacillus, Anerunibacillus, Paenibacillus, and Deinococcus, indicating a diversity of bacterial strains with potential industrial applications.

2.
Rev Argent Microbiol ; 56(2): 115-124, 2024.
Article de Espagnol | MEDLINE | ID: mdl-38155042

RÉSUMÉ

Waterborne diseases can have different origins, micro-organisms such as bacteria and parasites being the most important ones. In this study, two recreational aquatic environments were studied in the province of Salta, Argentina. Water samples collected from three different locations, two from a creek and one from the outlet of a thermal complex, were monitored at four time points. Physicochemical and microbiological characterization of each point was conducted, as well as a search for parasites and amebae. Parasites were identified through optical microscopy observations and free-living amebae (FLA) were isolated by spiking in Petri dishes followed by subsequent molecular identification. Water samples from the outlet of the thermal complex showed different physicochemical characteristics from those of the creek. Bacterial indicators of contamination were detected at all points; however, the creek water had a significantly higher concentration of Pseudomonas sp. Sporadically, creek samples exhibited Ascaris spp. eggs, Giardia sp. cysts, and ancylostomid eggs. The presence of FLA was observed in all samples, 15 of which were isolated and identified as Acanthamoeba sp., mostly belonging to the T4 genotype. Parasite surveillance in recreational aquatic environments is an important complement to traditional microbial indicators for assessing water quality. The identified parasites represent a potential health risk for people using these environments.


Sujet(s)
Loisir , Argentine , Animaux , Humains , Microbiologie de l'eau , Eau douce/parasitologie , Eau douce/microbiologie , Parasites/isolement et purification , Parasites/classification
3.
Pharmaceutics ; 15(10)2023 Sep 27.
Article de Anglais | MEDLINE | ID: mdl-37896152

RÉSUMÉ

The rheological and viscoelastic properties of hybrid formulations composed of vehicles designed for cutaneous topical application and loaded with ultradeformable liposomes (UDL) were assessed. UDL were selected for their established ability to transport both lipophilic and hydrophilic compounds through the skin, and are applicable in pharmaceuticals and cosmetics. Formulations underwent flow analysis and were fitted to the Herschel-Bulkley model due to their prevalent non-Newtonian behavior in most cases. Linear viscoelastic regions (LVR) were identified, and G' and G″ moduli were determined via frequency sweep steps, considering the impact of temperature and aging. The formulations exhibited non-Newtonian behavior with pseudoplastic traits in most cases, with UDL incorporation inducing rheological changes. LVR and frequency sweep tests indicated predominantly elastic solid behavior, with G' higher than G″, at different temperatures and post-production times. Tan δ values also illustrated a predominant solid-like behavior over liquid. This study provides pivotal insights into the rheological and viscoelastic features of topical formulations, emphasizing the crucial role of meticulous vehicle and formulation selection when incorporating UDL or analogous liposomal drug delivery systems.

4.
Microbiol Spectr ; : e0024923, 2023 Sep 27.
Article de Anglais | MEDLINE | ID: mdl-37754764

RÉSUMÉ

Temperature, pH, and hydrochemistry of terrestrial hot springs play a critical role in shaping thermal microbial communities. However, the interactions of biotic and abiotic factors at this terrestrial-aquatic interface are still not well understood on a global scale, and the question of how underground events influence microbial communities remains open. To answer this, 11 new samples obtained from the El Tatio geothermal field were analyzed by 16S rRNA amplicon sequencing (V4 region), along with 191 samples from previous publications obtained from the Taupo Volcanic Zone, the Yellowstone Plateau Volcanic Field, and the Eastern Tibetan Plateau, with their temperature, pH, and major ion concentration. Microbial alpha diversity was lower in acid-sulfate waters, and no significant correlations were found with temperature. However, moderate correlations were observed between chemical parameters such as pH (mostly constrained to temperatures below 70°C), SO4 2- and abundances of members of the phyla Armatimonadota, Deinococcota, Chloroflexota, Campilobacterota, and Thermoplasmatota. pH and SO4 2- gradients were explained by phase separation of sulfur-rich hydrothermal fluids and oxidation of reduced sulfur in the steam phase, which were identified as key processes shaping these communities. Ordination and permutational analysis of variance showed that temperature, pH, and major element hydrochemistry explain only 24% of the microbial community structure. Therefore, most of the variance remained unexplained, suggesting that other environmental or biotic factors are also involved and highlighting the environmental complexity of the ecosystem and its great potential to test niche theory ecological associated questions. IMPORTANCE This is the first approach to investigate whether geothermal processes could have an influence on the ecology of thermal microbial communities on a global scale. In addition to temperature and pH, microbial communities are structured by sulfate concentrations, which depends on the tectono-magmatic settings (such as the depth of magmatic chambers) and the local settings (such as the availability of a confining layer separating NaCl waters from steam after phase separation) and the possibility of mixing with more diluted fluids. Comparison of microbial communities from different geothermal areas by homogeneous sequence processing showed that no significant geographic distance decay was detected on the microbial communities according to Bray-Curtis, Jaccard, unweighted, and weighted Unifrac similarity/dissimilarity indices. Instead, an ancient potential divergence in the same taxonomic groups is suggested between globally distant thermal zones.

5.
Environ Geochem Health ; 44(7): 2301-2323, 2022 Jul.
Article de Anglais | MEDLINE | ID: mdl-35034269

RÉSUMÉ

The thermal mineral water of Peñón de los Baños spa (Mexico City) has been used for over 500 years starting in pre-Hispanic times and is famous for the treatment of various pathologies. It has a temperature of 45 °C, which is rich in HCO3-, and its main trace elements are B, Li and Fe, which confers healing effects. Concerns about the sustainability of this important spa have motivated this study to understand the thermal system, possible hydraulic and hydrochemical changes over time and its implications. Stable water isotope data indicate that the thermal water sources originate from local precipitation at Sierra de las Cruces with a recharge elevation of approximately 2770 m above sea level. The recharged water percolates through volcanic and carbonate rock formations and ascends via fault structure conduits, where it eventually is extracted 25 km downstream in Peñon de los Baños. During the gravity-driven deep circulation of up to 4.9 km, the groundwater is heated up to 136-160 °C. A comparison of past and current water levels and water chemical analyses indicates a water table drop and few variations in the chemical composition, confirming the presence of anthropic impact on water quality. Due to the heavy groundwater extractions in Mexico City, the spring water flow has ceased, and water must be pumped now from a 203-m deep well. In addition, the concentration of bicarbonate, sodium and chloride has been reduced by half since the onset of groundwater development. The therapeutic effects of this thermal mineral water are at risk due to the alteration of the chemical signature. However, new and different therapeutical uses may prevent a future deterioration or closure of this historically important thermal spa. It is crucial to establish a monitoring program of the thermal mineral water and reducing or minimizing nearby urban extractions which tap the regional flow component to preserve the properties of the thermal water.


Sujet(s)
Nappe phréatique , Eau minérale , Polluants chimiques de l'eau , Surveillance de l'environnement , Nappe phréatique/composition chimique , Isotopes/analyse , Eau minérale/analyse , Polluants chimiques de l'eau/analyse , Qualité de l'eau
6.
Surg. cosmet. dermatol. (Impr.) ; 12(4 S2): 141-148, fev.-nov. 2020.
Article de Portugais | LILACS-Express | LILACS | ID: biblio-1367832

RÉSUMÉ

O presente artigo de revisão relata os dados científicos disponíveis sobre a água termal La Roche-Posay e esclarece seus mecanismos de ação, suas indicações e seus benefícios clínicos. Além disso, estudos clínicos e avaliação genômica do microbioma da pele demonstraram que esta água termal melhora a diversidade do microbioma da pele e reduz a gravidade das lesões cutâneas em dermatoses inflamatórias, tais como dermatite atópica e psoríase. Justifica-se, portanto, o uso de água rica em selênio em formulações tópicas na prevenção ou tratamento de doenças de pele e como coadjuvante para aumentar a qualidade de vida dos pacientes dermatológicos.


This review article reports the scientific data available on La Roche-Posay thermal water and clarifies its mechanisms of action, indications, and clinical benefits. Clinical studies and genomic evaluation of the skin microbiome have shown that La Roche-Posay thermal water improves the skin microbiome's diversity and reduces the severity of skin lesions in inflammatory dermatoses, such as atopic dermatitis and psoriasis. Therefore, it justifies the use of selenium-rich water in topical formulations to prevent or treat skin diseases and as an adjunct to increase dermatological patients' quality of life

7.
Sci Total Environ ; 643: 423-434, 2018 Dec 01.
Article de Anglais | MEDLINE | ID: mdl-29945078

RÉSUMÉ

In the context of a regional Chilean project (FIC Taltape project, BIP code 30158422-0), a multi-effect distillation (MED) pilot plant has been built and installed in a small community in the north of Chile (Taltape, Arica) in order to supply treated water for agricultural and domestic purposes. The aim of this paper is to assess the techno-economic feasibility of this system for supplying water with the required quality to the population. The characterization of the feed water and the effluents from the MED pilot plant (distillate and brine), obtained during five months of operation, has been firstly performed. Then, the prediction of the operation of the water treatment system with solar energy has been carried out using a typical meteorological year and the design of a static solar field that cover the thermal energy needs of the water treatment plant. The annual simulations of the MED pilot plant operating with solar energy showed that the water needs can be mostly covered using a static solar thermal field with a total area of 113.2 m2, which would generate roughly 46% of the total heat required by the water treatment plant. The technical analysis has been completed with an exhaustive economic assessment. The specific water costs have been determined for the MED pilot plant and the scale factor when the productivity is increased up to 5000 m3/day has been evaluated. The cost of distillated water produced by the MED plant varied from 15.0 USD$/m3 for the 10 m3/day production capacity to 1.25 USD$/m3 when this variable is increased to 5000 m3/day.


Sujet(s)
Irrigation agricole/méthodes , Purification de l'eau/méthodes , Irrigation agricole/économie , Chili , Distillation , Eau , Purification de l'eau/économie , Alimentation en eau
8.
Movimento (Porto Alegre) ; 23(3)jul.-set. 2017.
Article de Portugais | LILACS | ID: biblio-868407

RÉSUMÉ

Resumo: As estâncias hidrominerais no Brasil se fizeram importante reduto de uma nova educação do corpo no início do século XX. Indicadas por um discurso médico que prescrevia uma fuga em direção à natureza, os novos divertimentos procurados pelos viajantes foram expressão de uma natureza domesticada pela mão humana e contraponto à vida na cidade. Entre curas, regenerações e divertimentos, este artigo propõe uma viagem em meio à natureza nas estâncias hidrominerais paulistas de Serra Negra e Águas de Lindoia, nas décadas de 1930 e 1940, período de seu esplendor, e tem como objetivo compreender de que forma essas estâncias, com suas indicações, prescrições e possibilidades, operavam uma determinada e específica educação do corpo dos visitantes. As fontes constituídas compreendem guias de viagens, revistas médicas e anais de congressos que tratam das águas termais. (AU)


Abstract: Thermal springs in Brazil were an important place for a new education of the body in the beginning of the 20th century. Whether they were within a medical discourse prescribing escape towards nature or new traveling destinations, they expressed nature domesticated by human hands and a counterpoint to urban life. Among healings, regenerations and amusements, this article proposes a trip amidst nature in the thermal springs of Serra Negra and Águas de Lindoia in the 1930s and 1940s, which were their days of glory. It aims at understanding how these thermal springs operated a determined and specific type of education in the bodies of their visito rs, with their many indications, prescriptions and possibilities. The sources include travel guides, medical journals and conference proceedings addressing the subject of thermal springs. (AU)


Resumen: Las estancias hidrominerales en Brasil pasaron a constituirse como importantes reductos de una nueva educación del cuerpo a inicios del siglo XX. Indicadas por un discurso médico que prescribía una fuga en dirección a la naturaleza, o como nuevos espacios de diversión buscados por los viajeros, fueron expresión de una naturaleza domesticada por la mano humana y como un contrapunto a la vida en las ciudades. Entre curas, regeneraciones y diversión, este artículo propone un viaje hacia aquella naturaleza de las estancias hidrominerales de Serra Negra y Águas de Lindoia, en São Paulo, en las décadas de 1930 y 1940, período de su máximo esplendor, y tiene como objetivo comprender de qué forma estas estancias, con sus indicaciones, prescripciones y posibilidades, operaban una determinada y específica educación del cuerpo de los visitantes. Las fuentes constituidas comprenden guías de viaje, revistas médicas y anales de congresos que tratan de las aguas termales. (AU)


Sujet(s)
Humains , Histoire du 20ème siècle , Hydrothérapie , Nature , Eau Thermale
9.
Rev. bras. ciênc. esporte ; 38(3): 213-219, jul.-set. 2016.
Article de Portugais | LILACS | ID: lil-795094

RÉSUMÉ

Resumo A natureza e seus elementos, como o sol, a água e o clima –considerados regeneradores –, afirmam-se nos discursos médicos como destinos apropriados aos viajantes durante as férias, estabelecidas legalmente aos trabalhadores com a Consolidação das Leis do Trabalho (CLT) em 1943. Este artigo trata das viagens de férias em estâncias hidrominerais e toma como objeto principal de análise um dos destinos: Poços de Caldas (MG). Seu objetivo foi analisar, a partir de um conjunto de revistas de vulgarização científica e guias de viagens das décadas de 1930 e 1940, o lugar da cura e do divertimento nessa estância. Analisa, assim, o lugar da educação do corpo nas prescrições voltadas para os destinos escolhidos.


Abstract Nature and its elements, such as sun, water, weather (all considered regenerative) are asserted in medical discourses as appropriate destinations for the vacations time, a worker's right legally established in 1943 by the CLT (Consolidações das Leis do Trabalho). This paper deals with vacation trips to thermal springs by analyzing one specific travelling destination: Poços de Caldas/MG. Based on a set of travel guides and magazines of scientific dissemination published in the decades of 1930 and 1940 we aim at analyzing this thermal spring as a place of healing and amusement. Thus, we analyze the role played by body education in the prescriptions of such travelling destinations.


Resumen La naturaleza y sus elementos, como el sol, el agua y el clima –considerados regeneradores– se afirman en los discursos médicos como destinos apropiados para los viajantes durante las vacaciones, establecidas legalmente para los trabajadores con las Consolidaciones de las Leyes del Trabajo (CLT) en 1943. Este artículo aborda los viajes de vacaciones en estancias hidrominerales y tiene como objetivo principal uno de los destinos: Pozos de Caldas, MG. Su objetivo fue analizar, a partir de un conjunto de revistas de divulgación científica y guías de viaje de las décadas de 1930 y 1940, el lugar de la cura y de la diversión en esa estancia. Analiza, asimismo, el lugar de la educación del cuerpo en las prescripciones orientadas a los destinos escogidos.

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