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1.
J Appl Microbiol ; 135(8)2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-39108090

RESUMEN

AIMS: This study aimed to describe the bacterial microbiome associated with the carapace of three species of Galapagos giant tortoises (Chelonoidis porteri, Chelonoidis donfaustoi, and Chelonoidis vandenburghi) and determine the potential effect of the whitish lesions caused by the fungus Aphanoascella galapagosensis. METHODS AND RESULTS: We used Oxford Nanopore's MinION to evaluate the external bacterial microbiome associated with the carapaces from the aforementioned species. Taxonomic assignment was carried out by Bugseq and the bacterial communities were compared between carapaces with and without lesions using a NMDS with Bray-Curtis as the dissimilarity index. We found four genera of bacteria that were ubiquitous throughout all individuals, suggesting the presence of shared taxa. The results also displayed a significant difference in the microbiome between carapaces with and without lesions, and for species-carapace interaction, but not among species. CONCLUSIONS: This study establishes a baseline of the bacterial diversity of the carapace within three Galapagos giant tortoise species, showcasing the presence of a distinctive microbial community. Furthermore, our findings suggest a significant influence of the fungus Aphanoascella galapagosensis on the bacterial populations inhabiting the carapace of these reptiles.


Asunto(s)
Bacterias , Microbiota , Tortugas , Animales , Tortugas/microbiología , Bacterias/clasificación , Bacterias/genética , Bacterias/aislamiento & purificación , Exoesqueleto/microbiología , Biodiversidad
2.
Front Bioeng Biotechnol ; 12: 1375984, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38812914

RESUMEN

Bacterial nanocellulose (BNC) is a sustainable, renewable, and eco-friendly nanomaterial, which has gained great attentions in both academic and industrial fields. Two bacterial nanocellulose-producing strains (CVV and CVN) were isolated from apple vinegar sources, presenting high 16S rRNA gene sequence similarities (96%-98%) with Komagataeibacter species. The biofilm was characterized by scanning electron microscopy (SEM), revealing the presence of rod-shaped bacteria intricately embedded in the polymeric matrix composed of nanofibers of bacterial nanocellulose. FTIR spectrum and XRD pattern additionally confirmed the characteristic chemical structure associated with this material. The yields and productivities achieved during 10 days of fermentation were compared with Komagataeibacter xylinus ATCC 53524, resulting in low levels of BNC production. However, a remarkable increase in the BNC yield was achieved for CVV (690% increase) and CVN (750% increase) strains at day 6 of the fermentation upon adding 22 mM citrate buffer into the medium. This effect is mainly attributed to the buffering capacity of the modified Yakamana medium, which allowed to maintain pH close to 4.0 until day 6, though in combination with additional factors including stimulation of the gluconeogenesis pathway and citrate assimilation as a carbon source. In addition, the productivities determined for both isolated strains (0.850 and 0.917 g L-1 d-1) compare favorably to previous works, supporting current efforts to improve fermentation performance in static cultures and the feasibility of scaling-up BNC production in these systems.

3.
Rev. cient. cienc. salud ; 5(1): 1-9, 26-01-2023.
Artículo en Español | LILACS, BDNPAR | ID: biblio-1437663

RESUMEN

Introducción:Escasos reportes sobre asma existen en la literatura nacional. El objetivo delestudio es describir ciertas características clínicas, las comorbilidades y el riesgo para apnea obstructiva del sueño (AOS) en este colectivo. Material y métodos:Mediante un estudio observacional tipo caso-control, se incluyeron pacientes portadores de asma de ambos sexos y un grupo control pareado por sexo y edad. Se consignaron datos demográficos, características de la enfermedad, datos relativos al control del asma y espirometría, comorbilidades y riesgo de apnea de sueño medido por el cuestionario STOP-BANG durante una entrevista estructurada. Resultados: Se incluyeron 132 individuos en el grupo caso y 132 en el grupo control. Entre los asmáticos, se consignaron 38,63% de formas no controladas y 9% severas. También se constató mayor frecuencia dehipertensión arterial, obesidad, rinitis alérgicay trastornos de la memoria. Riesgo mayor para AOS, aunque no significativo, se consignó en el grupo de casos. En el subgrupo de asmáticos con obesidad o en adultos mayores, la diferencia fue estadísticamente significativa-Discusión:Aundisponiendo de medicamentos preventivos,la tasa de control de los asmáticos en esta muestra es llamativa y merece estudios sistemáticos. Es extremadamente importante tener en cuenta algunas comorbilidades para el manejo de este grupo de pacientes,incluyendo la estratificación de riesgo para AOS.Palabras clave:asma; comorbilidad; apnea obstructiva del sueño


Introduction.Few reports on asthma exist in the national literature. The objective of our study is to describe certain clinical characteristics, comorbidities, and risk for obstructive sleep apnea (OSA) in this group. Material and methods.Through an observational case-control study, patients with asthma of both sexes and a control group matched by sex and age were included. Demographic data, disease characteristics, data related to asthma control and spirometry, comorbidities, and risk of sleep apnea measured by the STOP-BANG questionnaire were recorded during a structured interview. Results.132 individuals were included in the case group and 132 in the control group. Among the asthmatics, 38.63% of uncontrolled forms and 9% were severe. There was also a higher frequency of arterial hypertension, obesity, allergic rhinitis and memory disorders. Higher risk for OSA, although not significant, was recorded in the case group. In the subgroup of asthmatics with obesity or in older adults, the difference was relevant to the statistical analysis. Discussion.Even with preventive medications available, the control rate of asthmatics in this sample is striking and deserves systematic studies. It is extremely important to take into account some comorbidities for the management ofthis group of patients, including risk stratification for OSA.Key Words:asthma; comorbidity;obstructive sleep apnea


Asunto(s)
Humanos , Masculino , Femenino , Adolescente , Adulto , Persona de Mediana Edad , Asma , Comorbilidad , Apnea Obstructiva del Sueño
4.
Int. j. med. surg. sci. (Print) ; 8(2): 1-11, jun. 2021. tab, ilus
Artículo en Español | LILACS | ID: biblio-1284460

RESUMEN

La laringe es un órgano impar situado en la línea mediana del cuello, compuesto por cartílagos, músculos y ligamentos. La TC y la RM se realizan como técnicas de imagen de primera elección en el estudio de la laringe, no obstante, no están exentas de limitaciones. La ecografía es un método accesible, de alta resolución y presenta una relativa buena visualización de las diferentes estructuras de la laringe. El objetivo del trabajo fue determinar las características de estructuras anatómicas de la laringe identificables ecográficamente. En este trabajo de carácter observacional descriptivo de corte transversal prospectivo se estudiaron 20 pacientes, sin patología laríngea con edades entre 20 y 35 años, ambos sexos. Se realizó ecografía laríngea utilizando transductor ecográfico Phillips® con sonda lineal de 4 a 12 MHz, preset de partes blandas.En todos los casos se pudo identificar y medir los cartílagos tiroides, cricoides y epiglotis; y en gran porcentaje de estos las cuerdas vocales, bandas ventriculares y comisura anterior. El cartílago aritenoides solo fue visible en un 85% de los casos.La ecografía se presenta como un método auxiliar útil en el estudio de la anatomía de la laringe, proponiendo el seguimiento y realización de estudios ulteriores que puedan complementar este estudio y su validez.


The larynx is an odd organ located in the midline of the neck, composed of cartilage, muscles and ligaments. CT and MRI are performed as first-choice imaging techniques in the larynx study; however, they are not without limitations. Ultrasound is an accessible, high-resolution method with a relatively good visualization of the different structures of the larynx. The objective of the work was to determine the characteristics of ultrasoundly identifiable larynx anatomical structures.In this prospective cross-sectional descriptive observational work, 20 patients were studied, without laryngeal pathology aged between 20 and 35 years, both sexes. Laryngeal ultrasound was performed using Phillips® ultrasound transducer with linear probe from 4 to 12 MHz, soft parts presetThyroid cartilage, cricoids and epiglotis could be identified and measured in all cases, and in a large percentage of these the vocal cords, ventricular bands and anterior corner. Aritenoid cartilage was only visible in 85% of cases.Ultrasound is presented as a useful auxiliary method in the study of the anatomy of the larynx, proposing the follow-up and conduct of further studies that may complement this study and its validity


Asunto(s)
Humanos , Masculino , Femenino , Adulto , Adulto Joven , Laringe/anatomía & histología , Laringe/diagnóstico por imagen , Paraguay , Cartílago Aritenoides/anatomía & histología , Cartílago Aritenoides/diagnóstico por imagen , Cartílago Tiroides/anatomía & histología , Cartílago Tiroides/diagnóstico por imagen , Estudios Transversales , Estudios Prospectivos , Ultrasonografía , Cartílago Cricoides/anatomía & histología , Cartílago Cricoides/diagnóstico por imagen
5.
Int J Biol Macromol ; 165(Pt B): 2711-2720, 2020 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-33069824

RESUMEN

An environmentally friendly nanocomposite adsorbent composed of two renewable biomaterials, bacterial cellulose (BC) nanofibrils and hydroxyapatite (HA) nanocrystals, was synthetized by an in situ wet chemical precipitation technique, using clam shell biowaste as feedstock. HA nanocrystals embedded in an ultrafine BC network were confirmed and characterized trough different instrumental techniques (SEM, FTIR, XRD, EDS, surface charge and BET analysis), describing its nanostructure, chemical composition and thermal stability. The adsorptive removal of lead ions by the nanocomposite was investigated through batch experiments conducted under different pH, contact times and Pb(II) initial concentrations, proving that the process was highly favorable according to the Langmuir isotherm model (monolayer adsorption) with chemisorption as the main mechanism and kinetic data obeying a nonlinear pseudo-second order kinetic model. The developed nanocomposite showed a strong removal capacity of Pb(II) both in batch experiments (192 mg/g) and packed-bed column systems (188 mg/g), placing this new nanocomposite among top-performing BC-based biomaterials for lead removal.


Asunto(s)
Celulosa/química , Durapatita/química , Plomo/aislamiento & purificación , Contaminantes Químicos del Agua/aislamiento & purificación , Adsorción/efectos de los fármacos , Plomo/toxicidad , Nanocompuestos/química , Espectroscopía Infrarroja por Transformada de Fourier , Termodinámica , Agua/química , Contaminantes Químicos del Agua/toxicidad , Purificación del Agua/métodos
6.
Nat Commun ; 10(1): 556, 2019 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-30710076

RESUMEN

RESOLFT fluorescence nanoscopy can nowadays image details far beyond the diffraction limit. However, signal to noise ratio (SNR) and temporal resolution are still a concern, especially deep inside living cells and organisms. In this work, we developed a non-deterministic scanning approach based on a real-time feedback system which speeds up the acquisition up to 6-fold and decreases the light dose by 70-90% for in vivo imaging. Also, we extended the information content of the images by acquiring the complete temporal evolution of the fluorescence generated by reversible switchable fluorescent proteins. This generates a series of images with different spatial resolution and SNR, from conventional to RESOLFT images, which combined through a multi-image deconvolution algorithm further enhances the effective resolution. We reported nanoscale imaging of organelles up to 35 Hz and actin dynamics during an invasion process at a depth of 20-30 µm inside a living Caenorhabditis elegans worm.


Asunto(s)
Iluminación , Microscopía Fluorescente , Nanotecnología/métodos , Animales , Caenorhabditis elegans , Línea Celular , Supervivencia Celular , Toma de Decisiones , Hipocampo/citología , Humanos , Procesamiento de Imagen Asistido por Computador , Neuronas/citología , Ratas Sprague-Dawley , Factores de Tiempo , Imagen de Lapso de Tiempo
7.
Dev Cell ; 48(3): 313-328.e8, 2019 02 11.
Artículo en Inglés | MEDLINE | ID: mdl-30686527

RESUMEN

Matrix metalloproteinases (MMPs) are associated with decreased patient prognosis but have failed as anti-invasive drug targets despite promoting cancer cell invasion. Through time-lapse imaging, optical highlighting, and combined genetic removal of the five MMPs expressed during anchor cell (AC) invasion in C. elegans, we find that MMPs hasten invasion by degrading basement membrane (BM). Though irregular and delayed, AC invasion persists in MMP- animals via adaptive enrichment of the Arp2/3 complex at the invasive cell membrane, which drives formation of an F-actin-rich protrusion that physically breaches and displaces BM. Using a large-scale RNAi synergistic screen and a genetically encoded ATP FRET sensor, we discover that mitochondria enrich within the protrusion and provide localized ATP that fuels F-actin network growth. Thus, without MMPs, an invasive cell can alter its BM-breaching tactics, suggesting that targeting adaptive mechanisms will be necessary to mitigate BM invasion in human pathologies.


Asunto(s)
Actinas/metabolismo , Adenosina Trifosfato/metabolismo , Membrana Basal/metabolismo , Metaloproteinasas de la Matriz/metabolismo , Polimerizacion , Citoesqueleto de Actina/metabolismo , Animales , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/metabolismo , Membrana Celular/metabolismo , Movimiento Celular/fisiología , Regulación del Desarrollo de la Expresión Génica/fisiología , Proteínas del Tejido Nervioso/metabolismo
8.
RSC Adv ; 9(40): 22883-22890, 2019 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-35514475

RESUMEN

Hydroxyapatite (HA) was synthesized by wet chemical precipitation, using clam shell (CS) waste as feedstock. SEM and TEM observation of the produced hydroxyapatite revealed the presence of rod-shaped nanocrystals, while XRD and EDS analyses confirmed the characteristic patterns of hydroxyapatite molecules. This material was subsequently employed as a sorbent for heavy metal removal from aqueous solutions, both in batch and column equilibrium procedures. In batch studies, higher sorption efficiencies were obtained at pH 5, with the highest adsorption capacities of 265, 64, and 55 mg g-1 for Pb(ii), Cd(ii), and Cu(ii), respectively. In addition, an adsorption capacity of 42.5 mg g-1 was determined using a CS-HA packed bed column fed with a solution of Pb(ii). Finally, the breakthrough curve was fitted with Thomas model in order to predict column behavior and scaling up.

9.
Proc Natl Acad Sci U S A ; 115(45): 11537-11542, 2018 11 06.
Artículo en Inglés | MEDLINE | ID: mdl-30348801

RESUMEN

During invasion, cells breach basement membrane (BM) barriers with actin-rich protrusions. It remains unclear, however, whether actin polymerization applies pushing forces to help break through BM, or whether actin filaments play a passive role as scaffolding for targeting invasive machinery. Here, using the developmental event of anchor cell (AC) invasion in Caenorhabditis elegans, we observe that the AC deforms the BM and underlying tissue just before invasion, exerting forces in the tens of nanonewtons range. Deformation is driven by actin polymerization nucleated by the Arp2/3 complex and its activators, whereas formins and cross-linkers are dispensable. Delays in invasion upon actin regulator loss are not caused by defects in AC polarity, trafficking, or secretion, as appropriate markers are correctly localized in the AC even when actin is reduced and invasion is disrupted. Overall force production emerges from this study as one of the main tools that invading cells use to promote BM disruption in C. elegans.


Asunto(s)
Complejo 2-3 Proteico Relacionado con la Actina/metabolismo , Actinas/metabolismo , Membrana Basal/metabolismo , Caenorhabditis elegans/metabolismo , Regulación del Desarrollo de la Expresión Génica , Mecanotransducción Celular , Complejo 2-3 Proteico Relacionado con la Actina/genética , Actinas/genética , Animales , Membrana Basal/citología , Fenómenos Biomecánicos , Caenorhabditis elegans/citología , Caenorhabditis elegans/genética , Caenorhabditis elegans/crecimiento & desarrollo , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Movimiento Celular , Células Eucariotas/citología , Células Eucariotas/metabolismo , Proteínas Fetales/genética , Proteínas Fetales/metabolismo , Forminas , Genes Reporteros , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Laminina/genética , Laminina/metabolismo , Proteínas Luminiscentes/genética , Proteínas Luminiscentes/metabolismo , Proteínas de Microfilamentos/genética , Proteínas de Microfilamentos/metabolismo , Morfogénesis/genética , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Polimerizacion , Proteína Fluorescente Roja
10.
Rev. argent. cir. plást ; 23(1): 126-131, 20170000. fig
Artículo en Español | LILACS, BINACIS | ID: biblio-1391149

RESUMEN

Existen diferentes opciones para el tratamiento de la lipoatrofi a secundaria a la inyección local de esteroides. Presentamos las diferentes alternativas de tratamiento y sus resultados sobre cuatro pacientes con diferente grado de lesión y en diferentes áreas corporales.


There are diff erent options for the treatment of lipoatrophy secondary to the local injection of steroids. We present the diff erent treatment alternatives and their results on four patients with diff erent degrees of injury and in diff erent body areas.


Asunto(s)
Humanos , Esteroides/uso terapéutico , Triamcinolona Acetonida/uso terapéutico , Grasa Subcutánea/efectos de los fármacos , Grasa Subcutánea/lesiones , Solución Salina/uso terapéutico
11.
Biochim Biophys Acta ; 1853(11 Pt B): 3006-14, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26235437

RESUMEN

Actin filament dynamics have been studied for decades in pure protein solutions or in cell extracts, but a breakthrough in the field occurred at the turn of the century when it became possible to reconstitute networks of actin filaments, growing in a controlled but physiological manner on surfaces, mimicking the actin assembly that occurs at the plasma membrane during cell protrusion and cell shape changes. The story begins with the bacteria Listeria monocytogenes, the study of which led to the reconstitution of cellular actin polymerization on a variety of supports including plastic beads. These studies made possible the development of liposome-type substrates for filament assembly and micropatterning of actin polymerization nucleation. Based on the accumulated expertise of the last 15 years, many exciting approaches are being developed, including the addition of myosin to biomimetic actin networks to study the interplay between actin structure and contractility. The field is now poised to make artificial cells with a physiological and dynamic actin cytoskeleton, and subsequently to put these cells together to make in vitro tissues. This article is part of a Special Issue entitled: Mechanobiology.


Asunto(s)
Citoesqueleto de Actina/química , Proteínas Bacterianas/química , Listeria monocytogenes/química , Proteínas de la Membrana/química , Citoesqueleto de Actina/metabolismo , Animales , Proteínas Bacterianas/metabolismo , Humanos , Listeria monocytogenes/metabolismo , Proteínas de la Membrana/metabolismo
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