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1.
BMC Health Serv Res ; 24(1): 550, 2024 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-38685006

RESUMEN

BACKGROUND: Patient navigation is an evidence-based intervention that reduces cancer health disparities by directly addressing the barriers to care for underserved patients with cancer. Variability in design and integration of patient navigation programs within cancer care settings has limited this intervention's utility. The implementation science evaluation framework, RE-AIM, allows quantitative and qualitative examination of effective implementation of patient navigation programs into cancer care settings. METHODS: The Reach, Effectiveness, Adoption, Implementation, and Maintenance (RE-AIM) framework was used to evaluate implementation of a community-focused patient navigation intervention at an NCI-designated cancer center between June 2018 and October 2021. Using a 3-month longitudinal, non-comparative measurement period, univariate and bivariate analyses were conducted to examine associations between participant-level demographics and primary (i.e., barrier reduction) and secondary (i.e., patient-reported outcomes) effectiveness outcomes. Mixed methods analyses were used to examine adoption and delivery of the intervention into the cancer center setting. Process-level analyses were used to evaluate maintenance of the intervention. RESULTS: Participants (n = 311) represented a largely underserved population, as defined by the National Cancer Institute, with the majority identifying as Hispanic/Latino, having a household income of $35,000 or less, and being enrolled in Medicaid. Participants were diagnosed with a variety of cancer types and most had advanced staged cancers. Pre-post-intervention analyses indicated significant reduction from pre-intervention assessments in the average number of reported barriers, F(1, 207) = 117.62, p < .001, as well as significant increases in patient-reported physical health, t(205) = - 6.004, p < .001, mental health, t(205) = - 3.810, p < .001, self-efficacy, t(205) = - 5.321, p < .001, and satisfaction with medical team communication, t(206) = - 2.03, p = .029. Referral patterns and qualitative data supported increased adoption and integration of the intervention into the target setting, and consistent intervention delivery metrics suggested high fidelity to intervention delivery over time. Process-level data outlined a successful transition from a grant-funded community-focused patient navigation intervention to an institution-funded program. CONCLUSIONS: This study utilized the implementation science evaluation framework, RE-AIM, to evaluate implementation of a community-focused patient navigation program. Our analyses indicate successful implementation within a cancer care setting and provide a potential guide for other oncology settings who may be interested in implementing community-focused patient navigation programs.


Asunto(s)
Instituciones Oncológicas , National Cancer Institute (U.S.) , Neoplasias , Navegación de Pacientes , Humanos , Navegación de Pacientes/métodos , Navegación de Pacientes/organización & administración , Masculino , Femenino , Estados Unidos , Persona de Mediana Edad , Neoplasias/terapia , Instituciones Oncológicas/organización & administración , Estudios Longitudinales , Evaluación de Programas y Proyectos de Salud , Adulto , Accesibilidad a los Servicios de Salud , Anciano
2.
Plant Dis ; : PDIS07231359RE, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-37923978

RESUMEN

Botryosphaeria dieback, caused by a group of pathogens in the Botryosphaeriaceae family, is one of the most common grapevine trunk disease complexes (GTDs) found in Oregon vineyards. To understand the period of spores released by Botryosphaeria spp. in Oregon vineyards, four Burkard 7-day recording volumetric spore traps were placed in vineyard blocks in northern and southern Oregon. Each trap was placed near a younger (<10 years) and older (>30 years) block in both regions. Spore traps were deployed at the beginning of December 2019 and continued until March 2021. Between these timeframes, 475 and 477 days of samples were collected from each spore trap in northern and southern Oregon, respectively. DNA extraction was performed from individual day samples and followed by qPCR analysis of Botryosphaeria spores trapped in each tape sample. Weather data such as temperature, precipitation, relative humidity (RH), and wind speed were collected from nearby weather stations. Association between these data and number of spores detected were analyzed using Pearson correlation analysis. In northern Oregon, the detection occurred between December and February, and the first spore detection occurred when cumulative growing degree day (GDD) totaled to 4,357 and 4,351 units (TBase = 0°C, biofix date = January 1) during the first and second seasons, respectively. Similarly, in southern Oregon, the detection occurred between November and January, and the first spore detection occurred when cumulative GDD was 4,405 units during the second season. Hours of continuous RH >86% was significantly associated with number of spores released (P = 0.026; r = 0.42). During the spore detected dates, the RH was >86% for at least 19 consecutive hours. These findings provide an important implication to manage Botryosphaeria dieback by protecting pruning wounds during the most-spore-released periods. Furthermore, the knowledge of weather variables and their possible association with spore detection provides important information towards developing predictive models in future studies.

3.
Int J Mol Sci ; 25(13)2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-39000050

RESUMEN

Targeted NGS allows a fast and efficient multi-gene analysis and the detection of key gene aberrations in melanoma. In this study, we aim to describe the genetic alterations in a series of 87 melanoma cases using the oncomine focus assay (OFA), relate these results with the clinicopathological features of the patients, and compare them with our previous study results in which we used a smaller panel, the oncomine solid tumor (OST) DNA kit. Patients diagnosed with advanced melanoma at our center from 2020 to 2022 were included and DNA and RNA were extracted for sequencing. Common mutated genes were BRAF (29%), NRAS (28%), ALK, KIT, and MAP2K1 (5% each). Co-occurring mutations were detected in 29% of the samples, including BRAF with KIT, CTNNB1, EGFR, ALK, HRAS, or MAP2K1. Amplifications and rearrangements were detected in 5% of cases. Only BRAF mutation showed a significant statistical association with sun exposure. For patients with a given genetic profile, the melanoma survival and recurrence-free survival rates were equivalent, but not for stage and LDH values. This expanded knowledge of molecular alterations has helped to more comprehensively characterize our patients and has provided relevant information for deciding the best treatment strategy.


Asunto(s)
Melanoma , Mutación , Humanos , Melanoma/genética , Melanoma/patología , Melanoma/terapia , Masculino , Femenino , Persona de Mediana Edad , Anciano , España , Adulto , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Anciano de 80 o más Años , Estudios de Factibilidad , Proteínas Proto-Oncogénicas B-raf/genética , Biomarcadores de Tumor/genética , Neoplasias Cutáneas/genética , Neoplasias Cutáneas/patología
4.
Int J Aging Hum Dev ; 99(1): 3-24, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38354308

RESUMEN

Predictors of health across the life-course do not maintain the same significance in very late life and the role of financial strain in health outcomes of very old adults remain unclear. Data from adults aged 74 + in waves 5 and 7 of the Hispanic Established Population for the Epidemiological Study of the Elderly (n = 772) study was used to evaluate the role of financial strain on the health of older Mexican Americans who have the highest poverty rate of any racial or ethnic group in the United States. We evaluate the association between episodic (one wave) and persistent financial strain (two waves), with follow-up health outcomes (self-rated health, ADL (limitations in activities of daily living)/IADL (limitations in instrumental activities of daily living) disability, and depressive symptoms). Adults with persistent strain were twice as likely to experience depressive symptoms and three times more likely to experience IADL limitations than the unstrained. Our findings highlight the role of stress proliferation and allostatic load processes leading to deteriorated health over time.


Asunto(s)
Actividades Cotidianas , Depresión , Estado de Salud , Americanos Mexicanos , Humanos , Masculino , Anciano , Femenino , Americanos Mexicanos/estadística & datos numéricos , Americanos Mexicanos/psicología , Actividades Cotidianas/psicología , Anciano de 80 o más Años , Depresión/epidemiología , Depresión/etnología , Depresión/psicología , Estados Unidos/epidemiología , Estados Unidos/etnología , Estrés Financiero/etnología , Estrés Financiero/psicología
5.
BMC Cancer ; 23(1): 380, 2023 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-37101114

RESUMEN

BACKGROUND: Dihydropyrimidine dehydrogenase (DPD) is a key enzyme in the metabolism of fluoropyrimidines. Variations in the encoding DPYD gene are associated with severe fluoropyrimidine toxicity and up-front dose reductions are recommended. We conducted a retrospective study to evaluate the impact of implementing DPYD variant testing for patients with gastrointestinal cancers in routine clinical practice in a high volume cancer centre in London, United Kingdom. METHODS: Patients receiving fluoropyrimidine chemotherapy for gastrointestinal cancer prior to, and following the implementation of DPYD testing were identified retrospectively. After November 2018, patients were tested for DPYD variants c.1905+1G>A (DPYD*2A), c.2846A>T (DPYD rs67376798), c.1679T>G (DPYD*13), c.1236G>A (DPYD rs56038477), c.1601G>A (DPYD*4) prior to commencing fluoropyrimidines alone or in combination with other cytotoxics and/or radiotherapy. Patients with a DPYD heterozygous variant received an initial dose reduction of 25-50%. Toxicity by CTCAE v4.03 criteria was compared between DPYD heterozygous variant and wild type carriers. RESULTS: Between 1st December 2018 and 31st July 2019, 370 patients who were fluoropyrimidine naïve underwent a DPYD genotyping test prior to receiving a capecitabine (n = 236, 63.8%) or 5FU (n = 134, 36.2%) containing chemotherapy regimen. 33 patients (8.8%) were heterozygous DPYD variant carriers and 337 (91.2%) were wild type. The most prevalent variants were c.1601G > A (n = 16) and c.1236G > A (n = 9). Mean relative dose intensity for the first dose was 54.2% (range 37.5-75%) for DPYD heterozygous carriers and 93.2% (42.9-100%) for DPYD wild type carriers. Overall grade 3 or worse toxicity was similar in DPYD variant carriers (4/33, 12.1%) as compared to wild-type carriers (89/337, 25.7%; P = 0.0924). CONCLUSIONS: Our study demonstrates successful routine DPYD mutation testing prior to the initiation of fluoropyrimidine chemotherapy with high uptake. In patients with DPYD heterozygous variants with pre-emptive dose reductions, high incidence of severe toxicity was not observed. Our data supports routine DPYD genotype testing prior to commencement of fluoropyrimidine chemotherapy.


Asunto(s)
Dihidrouracilo Deshidrogenasa (NADP) , Neoplasias Gastrointestinales , Humanos , Dihidrouracilo Deshidrogenasa (NADP)/genética , Estudios Retrospectivos , Fluorouracilo/efectos adversos , Farmacogenética , Capecitabina , Genotipo , Neoplasias Gastrointestinales/tratamiento farmacológico , Neoplasias Gastrointestinales/genética
6.
Plant Dis ; 107(5): 1355-1364, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36089679

RESUMEN

Grapevine trunk diseases (GTDs) are found in vineyards worldwide and can be caused by different fungal pathogens. To characterize types of GTDs in Oregon vineyards, and how the GTD pathogens' prevalence is affected by two geographical regions, a survey was conducted in which grapevine trunk samples were collected from 15 and 14 wine grape (Vitis vinifera) vineyards in southern and northern Oregon, respectively. Fungal species were identified through culture and PCR-based methods. GTD pathogens that were identified included Botryosphaeriaceae spp. and Phaeoacremonium spp. from 72 and 21% of the surveyed vineyards, respectively; Phaeomoniella chlamydospora, Cryptovalsa ampelina, Truncatella angustata, Seimatosporium lichenicola, Hormonema viticola from 7% of the surveyed vineyards; and Dactylonectria macrodidyma, and Pestaloptiopsis sp. from 3% of the surveyed vineyards. Pathogens were identified in both regions and in young and mature vineyards. The presence of GTD from the Botryosphaeria dieback complex was significantly affected by regions (P = 0.021), with pathogens being significantly more abundant in Willamette Valley (northern region) compared with Rogue Valley (southern region) vineyards. Some differences among other tested variables such as vineyard age, cultivars, rootstocks, and pruning methods were observed for all disease complexes; however, the differences were not statistically significant. Our study summarizes that Botryosphaeria dieback and Esca disease complexes are the most prevalent diseases infecting grapevines in Oregon vineyards and management practices need to be geared toward these economically important diseases. In addition, pathogens from other disease complexes are also present, suggesting a need for regular disease monitoring and following practices to limit the spread of these pathogens.


Asunto(s)
Granjas , Oregon , Prevalencia
7.
Salud Publica Mex ; 65(5, sept-oct): 425-433, 2023 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-38060921

RESUMEN

OBJECTIVE: We developed a MHAS (Mexican Health and Aging Study) and O*NET (Occupational Information Network) linkage to allow global researchers using MHAS data to assign lifetime occupation domains for older Mexicans. MATERIALS AND METHODS: Three bilingual raters independently matched 440 records with 132 unique occupation codes from the 2012 MHAS. We used a modified Delphi technique to reach agreements. To assess reliability, we compared the distribution of observations between the MHAS file and the MHAS-O*NET linked file across five job categories (upper white collar, lower white collar, upper blue collar, low blue collar, and agriculture/fishing/forestry). The Institutional Review Board at the University of Texas Medical Branch reviewed and approved the research (IRB # 21-0268). RESULTS: Using the developed 1:1 MHAS-ONET linkage, consistency between MHAS and ONET was 97.4% across the five job categories. CONCLUSION: This MHAS-O*NET linkage will allow researchers to analyze the association between lifetime occupation and multiple dimensions of health, functionality, and retirement determinants for a low-middle income country with a large proportion of workers in the informal sector.


Asunto(s)
Envejecimiento , Ocupaciones , Humanos , Reproducibilidad de los Resultados , México
8.
Sensors (Basel) ; 23(15)2023 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-37571449

RESUMEN

Experiences of virtual reality (VR) can easily break if the method of evaluating subjective user states is intrusive. Behavioral measures are increasingly used to avoid this problem. One such measure is eye tracking, which recently became more standard in VR and is often used for content-dependent analyses. This research is an endeavor to utilize content-independent eye metrics, such as pupil size and blinks, for identifying mental load in VR users. We generated mental load independently from visuals through auditory stimuli. We also defined and measured a new eye metric, focus offset, which seeks to measure the phenomenon of "staring into the distance" without focusing on a specific surface. In the experiment, VR-experienced participants listened to two native and two foreign language stimuli inside a virtual phone booth. The results show that with increasing mental load, relative pupil size on average increased 0.512 SDs (0.118 mm), with 57% reduced variance. To a lesser extent, mental load led to fewer fixations, less voluntary gazing at distracting content, and a larger focus offset as if looking through surfaces (about 0.343 SDs, 5.10 cm). These results are in agreement with previous studies. Overall, we encourage further research on content-independent eye metrics, and we hope that hardware and algorithms will be developed in the future to further increase tracking stability.


Asunto(s)
Realidad Virtual , Humanos , Percepción Auditiva , Lenguaje , Interfaz Usuario-Computador , Encuestas y Cuestionarios
9.
Int J Mol Sci ; 24(10)2023 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-37240108

RESUMEN

Previously, functional coatings on 3D-printed titanium implants were developed to improve their biointegration by separately incorporating Ga and Ag on the biomaterial surface. Now, a thermochemical treatment modification is proposed to study the effect of their simultaneous incorporation. Different concentrations of AgNO3 and Ga(NO3)3 are evaluated, and the obtained surfaces are completely characterized. Ion release, cytotoxicity, and bioactivity studies complement the characterization. The provided antibacterial effect of the surfaces is analyzed, and cell response is assessed by the study of SaOS-2 cell adhesion, proliferation, and differentiation. The Ti surface doping is confirmed by the formation of Ga-containing Ca titanates and nanoparticles of metallic Ag within the titanate coating. The surfaces generated with all combinations of AgNO3 and Ga(NO3)3 concentrations show bioactivity. The bacterial assay confirms a strong bactericidal impact achieved by the effect of both Ga and Ag present on the surface, especially for Pseudomonas aeruginosa, one of the main pathogens involved in orthopedic implant failures. SaOS-2 cells adhere and proliferate on the Ga/Ag-doped Ti surfaces, and the presence of gallium favors cell differentiation. The dual effect of both metallic agents doping the titanium surface provides bioactivity while protecting the biomaterial from the most frequent pathogens in implantology.


Asunto(s)
Galio , Titanio , Titanio/farmacología , Titanio/química , Plata/farmacología , Plata/química , Oseointegración , Porosidad , Galio/farmacología , Materiales Biocompatibles Revestidos/farmacología , Materiales Biocompatibles Revestidos/química , Antibacterianos/farmacología , Antibacterianos/química , Propiedades de Superficie
10.
Behav Res Methods ; 2023 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-37864116

RESUMEN

Facial neuromuscular electrical stimulation (fNMES), which allows for the non-invasive and physiologically sound activation of facial muscles, has great potential for investigating fundamental questions in psychology and neuroscience, such as the role of proprioceptive facial feedback in emotion induction and emotion recognition, and may serve for clinical applications, such as alleviating symptoms of depression. However, despite illustrious origins in the 19th-century work of Duchenne de Boulogne, the practical application of fNMES remains largely unknown to today's researchers in psychology. In addition, published studies vary dramatically in the stimulation parameters used, such as stimulation frequency, amplitude, duration, and electrode size, and in the way they reported them. Because fNMES parameters impact the comfort and safety of volunteers, as well as its physiological (and psychological) effects, it is of paramount importance to establish recommendations of good practice and to ensure studies can be better compared and integrated. Here, we provide an introduction to fNMES, systematically review the existing literature focusing on the stimulation parameters used, and offer recommendations on how to safely and reliably deliver fNMES and on how to report the fNMES parameters to allow better cross-study comparison. In addition, we provide a free webpage, to easily visualise fNMES parameters and verify their safety based on current density. As an example of a potential application, we focus on the use of fNMES for the investigation of the facial feedback hypothesis.

11.
Sensors (Basel) ; 22(10)2022 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-35632143

RESUMEN

This work proposes a unifying framework for extending PDE-constrained Large Deformation Diffeomorphic Metric Mapping (PDE-LDDMM) with the sum of squared differences (SSD) to PDE-LDDMM with different image similarity metrics. We focused on the two best-performing variants of PDE-LDDMM with the spatial and band-limited parameterizations of diffeomorphisms. We derived the equations for gradient-descent and Gauss-Newton-Krylov (GNK) optimization with Normalized Cross-Correlation (NCC), its local version (lNCC), Normalized Gradient Fields (NGFs), and Mutual Information (MI). PDE-LDDMM with GNK was successfully implemented for NCC and lNCC, substantially improving the registration results of SSD. For these metrics, GNK optimization outperformed gradient-descent. However, for NGFs, GNK optimization was not able to overpass the performance of gradient-descent. For MI, GNK optimization involved the product of huge dense matrices, requesting an unaffordable memory load. The extensive evaluation reported the band-limited version of PDE-LDDMM based on the deformation state equation with NCC and lNCC image similarities among the best performing PDE-LDDMM methods. In comparison with benchmark deep learning-based methods, our proposal reached or surpassed the accuracy of the best-performing models. In NIREP16, several configurations of PDE-LDDMM outperformed ANTS-lNCC, the best benchmark method. Although NGFs and MI usually underperformed the other metrics in our evaluation, these metrics showed potentially competitive results in a multimodal deformable experiment. We believe that our proposed image similarity extension over PDE-LDDMM will promote the use of physically meaningful diffeomorphisms in a wide variety of clinical applications depending on deformable image registration.


Asunto(s)
Algoritmos , Encéfalo , Benchmarking
12.
Int J Mol Sci ; 23(3)2022 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-35163682

RESUMEN

A lack of primary stability and osteointegration in metallic implants may result in implant loosening and failure. Adding porosity to metallic implants reduces the stress shielding effect and improves implant performance, allowing the surrounding bone tissue to grow into the scaffold. However, a bioactive surface is needed to stimulate implant osteointegration and improve mechanical stability. In this study, porous titanium implants were produced via powder sintering to create different porous diameters and open interconnectivity. Two strategies were used to generate a bioactive surface on the metallic foams: (1) an inorganic alkali thermochemical treatment, (2) grafting a cell adhesive tripeptide (RGD). RGD peptides exhibit an affinity for integrins expressed by osteoblasts, and have been reported to improve osteoblast adhesion, whereas the thermochemical treatment is known to improve titanium implant osseointegration upon implantation. Bioactivated scaffolds and control samples were implanted into the tibiae of rabbits to analyze the effect of these two strategies in vivo regarding bone tissue regeneration through interconnected porosity. Histomorphometric evaluation was performed at 4 and 12 weeks after implantation. Bone-to-implant contact (BIC) and bone in-growth and on-growth were evaluated in different regions of interest (ROIs) inside and outside the implant. The results of this study show that after a long-term postoperative period, the RGD-coated samples presented higher quantification values of quantified newly formed bone tissue in the implant's outer area. However, the total analyzed bone in-growth was observed to be slightly greater in the scaffolds treated with alkali thermochemical treatment. These results suggest that both strategies contribute to enhancing porous metallic implant stability and osteointegration, and a combination of both strategies might be worth pursuing.


Asunto(s)
Álcalis/farmacología , Materiales Biocompatibles Revestidos/farmacología , Metalurgia , Oligopéptidos/farmacología , Oseointegración , Temperatura , Andamios del Tejido/química , Titanio/farmacología , Animales , Femenino , Implantes Experimentales , Oseointegración/efectos de los fármacos , Osteogénesis/efectos de los fármacos , Porosidad , Polvos , Conejos
13.
J Prosthet Dent ; 127(3): 470-476, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33309211

RESUMEN

STATEMENT OF PROBLEM: Polyetheretherketone (PEEK) has been advocated to replace metal components in dentistry. Although PEEK is a high-performance polymer with a white color, adequate biological response, and resistance to fracture, data to support PEEK as an alternative material for implant abutments are lacking. PURPOSE: The purpose of this in vitro study was to assess the mechanical and functional properties of PEEK implant abutments as a nonmetallic alternative to titanium abutments, which presents esthetic limitations and greater difficulty to customize clinically. MATERIAL AND METHODS: Implant abutments manufactured by using PEEK (n=24) or titanium grade 5 (n=24) were attached to MIS Implants type M4 3.75×16 mm with an internal screw tightened to 25 Ncm. Screw loosening and microleakage was assessed by submersion in a 2% methylene blue solution for 48 hours at 37 °C. Both groups were compared with and without applying dynamic loading; fatigue testing was performed following the International Organization for Standardization (ISO) 14801:2016 standard. All specimens were observed under a stereomicroscope at ×8 magnification. Statistically significant differences among the PEEK and titanium implant abutments were tested with 2-factor ANOVA and the chi-square analysis for nonpaired and paired data, respectively (α=.05). RESULTS: The implant abutments made of titanium were better in all mechanical tests. The torque loss of titanium abutments was approximately 10%, while PEEK showed a significantly higher (P<.05) torque loss of up to 50%. Moreover, 91.6% of the titanium abutments did not present microleakage, while there was no specimen of PEEK abutments without microleakage, once subjected to dynamic loading (P<.05). CONCLUSIONS: Titanium implant abutments (Ti6Al4V) were better in all tests performed. However, PEEK abutments may be suitable for long-term interim restorations, especially in the anterior area, in patients without parafunction.


Asunto(s)
Implantes Dentales , Titanio , Benzofenonas , Tornillos Óseos , Pilares Dentales , Diseño de Implante Dental-Pilar , Fracaso de la Restauración Dental , Análisis del Estrés Dental , Estética Dental , Humanos , Ensayo de Materiales , Pruebas Mecánicas , Polímeros , Circonio
14.
Biomacromolecules ; 22(6): 2338-2351, 2021 06 14.
Artículo en Inglés | MEDLINE | ID: mdl-33961400

RESUMEN

We present here a series of thermoresponsive glycopolymers in the form of poly(N-isopropylacrylamide)-co-(2-[ß-manno[oligo]syloxy] ethyl methacrylate)s. These copolymers were prepared from oligo-ß-mannosyl ethyl methacrylates that were synthesized through enzymatic catalysis, and were subsequently investigated with respect to their aggregation and phase behavior in aqueous solution using a combination of 1H NMR spectroscopy, dynamic light scattering, cryogenic transmission electron microscopy (TEM), and small-angle X-ray scattering (SAXS). The thermoresponsive glycopolymers were prepared by conventional free radical copolymerization of different mixtures of 2-(ß-manno[oligo]syloxy)ethyl methacrylates (with either one or two saccharide units) and N-isopropylacrylamide (NIPAm). The results showed that below the lower critical solution temperature (LCST) of poly(NIPAm), the glycopolymers readily aggregate into nanoscale structures, partly due to the presence of the saccharide moieties. Above the LCST of poly(NIPAm), the glycopolymers rearrange into a heterogeneous mixture of fractal and disc/globular aggregates. Cryo-TEM and SAXS data demonstrated that the presence of the pendant ß-mannosyl moieties in the glycopolymers induces a gradual conformational change over a wide temperature range. Even though the onset of this transition is not different from the LCST of poly(NIPAm), the gradual conformational change offers a variation of the temperature-dependent properties in comparison to poly(NIPAm), which displays a sharp coil-to-globule transition. Importantly, the compacted form of the glycopolymers shows a larger colloidal stability compared to the unmodified poly(NIPAm). In addition, the thermoresponsiveness can be conveniently tuned by varying the sugar unit-length and the oligo-ß-mannosyl ethyl methacrylate content.


Asunto(s)
Acrilamidas , Metacrilatos , Dispersión del Ángulo Pequeño , Temperatura , Difracción de Rayos X
15.
Nature ; 528(7583): 560-564, 2015 Dec 24.
Artículo en Inglés | MEDLINE | ID: mdl-26649819

RESUMEN

Epithelial regeneration is critical for barrier maintenance and organ function after intestinal injury. The intestinal stem cell (ISC) niche provides Wnt, Notch and epidermal growth factor (EGF) signals supporting Lgr5(+) crypt base columnar ISCs for normal epithelial maintenance. However, little is known about the regulation of the ISC compartment after tissue damage. Using ex vivo organoid cultures, here we show that innate lymphoid cells (ILCs), potent producers of interleukin-22 (IL-22) after intestinal injury, increase the growth of mouse small intestine organoids in an IL-22-dependent fashion. Recombinant IL-22 directly targeted ISCs, augmenting the growth of both mouse and human intestinal organoids, increasing proliferation and promoting ISC expansion. IL-22 induced STAT3 phosphorylation in Lgr5(+) ISCs, and STAT3 was crucial for both organoid formation and IL-22-mediated regeneration. Treatment with IL-22 in vivo after mouse allogeneic bone marrow transplantation enhanced the recovery of ISCs, increased epithelial regeneration and reduced intestinal pathology and mortality from graft-versus-host disease. ATOH1-deficient organoid culture demonstrated that IL-22 induced epithelial regeneration independently of the Paneth cell niche. Our findings reveal a fundamental mechanism by which the immune system is able to support the intestinal epithelium, activating ISCs to promote regeneration.


Asunto(s)
Células Epiteliales/citología , Interleucinas/inmunología , Mucosa Intestinal/citología , Intestino Delgado/citología , Regeneración , Células Madre/citología , Células Madre/metabolismo , Animales , Células Epiteliales/inmunología , Células Epiteliales/patología , Femenino , Enfermedad Injerto contra Huésped/patología , Humanos , Inmunidad Mucosa , Interleucinas/deficiencia , Mucosa Intestinal/inmunología , Mucosa Intestinal/patología , Intestino Delgado/inmunología , Intestino Delgado/patología , Ratones , Organoides/citología , Organoides/crecimiento & desarrollo , Organoides/inmunología , Células de Paneth/citología , Fosforilación , Factor de Transcripción STAT3/metabolismo , Transducción de Señal , Nicho de Células Madre , Interleucina-22
16.
J Trop Pediatr ; 67(1)2021 01 29.
Artículo en Inglés | MEDLINE | ID: mdl-33823049

RESUMEN

INTRODUCTION: The SARS-CoV-2/COVID-19 may produce neurological manifestations, including its occurrence in children, and newborns, which has been little reported so far in newborns with COVID-19. CASE: We present a case in Colombia, of community-acquired neonatal infection of SARS-CoV-2, with suggestive symptoms, such as fever, and showing neurological findings, such as drowsiness, poor suction and mild hypotonia for a short time. DISCUSSION: The clinical manifestations of SARS-COV-2 in neonates are beginning to be described in detail. We report a case of SARS-COV-2-associated neurological compromise in a newborn, with features of drowsiness, poor suction and hypotonia.


Asunto(s)
COVID-19/complicaciones , Infecciones Comunitarias Adquiridas/virología , Enfermedades del Sistema Nervioso/virología , COVID-19/diagnóstico , Colombia , Infecciones Comunitarias Adquiridas/diagnóstico , Fiebre/virología , Humanos , Recién Nacido , Hipotonía Muscular/virología , Somnolencia
17.
J Occup Environ Hyg ; 18(6): 265-275, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33989113

RESUMEN

The COVID-19 pandemic has caused a high demand for respiratory protection among health care workers in hospitals, especially surgical N95 filtering facepiece respirators (FFRs). To aid in alleviating that demand, a survey of commercially available filter media was conducted to determine whether any could serve as a substitute for an N95 FFR while held in a 3D-printed mask (Stopgap Surgical Face Mask from the NIH 3D Print Exchange). Fourteen filter media types and eight combinations were evaluated for filtration efficiency, breathing resistance (pressure drop), and liquid penetration. Additional testing was conducted to evaluate two filter media disinfection methods in the event that the filters were reused in a hospital setting. Efficiency testing was conducted in accordance with the procedures established for approving an N95 FFR. One apparatus used a filter-holding device and another apparatus employed a manikin head to which the 3D-printed mask could be sealed. The filter media and combinations exhibited collection efficiencies varied between 3.9% and 98.8% when tested with a face velocity comparable to that of a standard N95 FFR at the 85 L min-1 used in the approval procedure. Breathing resistance varied between 10.8 to >637 Pa (1.1 to > 65 mm H2O). When applied to the 3D-printed mask efficiency decreased by an average of 13% and breathing resistance increased 4-fold as a result of the smaller surface area of the filter media when held in that mask compared to that of an N95 FFR. Disinfection by dry heat, even after 25 cycles, did not significantly affect filter efficiency and reduced viral infectivity by > 99.9%. However, 10 cycles of 59% vaporized H2O2 significantly (p < 0.001) reduced filter efficiency of the media tested. Several commercially available filter media were found to be potential replacements for the media used to construct the typical cup-like N95 FFR. However, their use in the 3D-printed mask demonstrated reduced efficiency and increased breathing resistance at 85 L min-1.


Asunto(s)
COVID-19/prevención & control , Desinfección/normas , Contaminación de Equipos/prevención & control , Ensayo de Materiales/normas , Respiradores N95/virología , Exposición Profesional/prevención & control , Pandemias/prevención & control , Contaminantes Ocupacionales del Aire/análisis , Análisis de Falla de Equipo/estadística & datos numéricos , Guías como Asunto , Humanos , Exposición por Inhalación/análisis , SARS-CoV-2
18.
Eur J Immunol ; 49(2): 290-301, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30537036

RESUMEN

Under homeostatic conditions, dendritic cells (DCs) continuously patrol the intestinal lamina propria. Upon antigen encounter, DCs initiate C-C motif chemokine receptor 7 (CCR7) expression and migrate into lymph nodes to direct T cell activation and differentiation. The mechanistic underpinnings of DC migration from the tissues to lymph nodes have been largely elucidated, contributing greatly to our understanding of DC functionality and intestinal immunity. In contrast, the molecular mechanisms allowing DCs to efficiently migrate through the complex extracellular matrix of the intestinal lamina propria prior to antigen encounter are still incompletely understood. Here we show that small intestinal murine CD11b+ CD103+ DCs express Placenta-expressed transcript 1 (Plet1), a glycophoshatidylinositol (GPI)-anchored surface protein involved in migration of keratinocytes during wound healing. In the absence of Plet1, CD11b+ CD103+ DCs display aberrant migratory behavior, and accumulate in the small intestine, independent of CCR7 responsiveness. RNA-sequencing indicated involvement of Plet1 in extracellular matrix-interactiveness, and subsequent in-vitro migration assays revealed that Plet1 augments the ability of DCs to migrate through extracellular matrix containing environments. In conclusion, our findings reveal that expression of Plet1 facilitates homeostatic interstitial migration of small intestinal DCs.


Asunto(s)
Movimiento Celular/inmunología , Células Dendríticas/metabolismo , Regulación de la Expresión Génica/inmunología , Intestino Delgado/inmunología , Proteínas Gestacionales/inmunología , Animales , Antígenos CD/genética , Antígenos CD/inmunología , Movimiento Celular/genética , Ratones , Ratones Noqueados , Proteínas Gestacionales/genética
19.
Soft Matter ; 16(30): 7063-7076, 2020 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-32756673

RESUMEN

The substantial part of the water-soluble hemicellulose fraction, obtained when processing cellulose to produce paper and other products, has so far been discarded. The aim of this work is to reveal the interfacial properties of softwood hemicellulose (galactoglucomannan, GGM) in relation to their molecular and solution structure. In this study the sugar composition of GGM was characterised by chemical analysis as well as 1D and 2D NMR spectroscopy. Previously it has been demonstrated that hemicellulose has high affinity towards cellulose and has the ability to alter the properties of cellulose based products. This study is focused on the interactions between hemicellulose and the cellulose surface. Therefore, adsorption to hydrophobized silica and cellulose surfaces of two softwood hemicellulose samples and structurally similar seed hemicelluloses (galactomannans, GMs) was studied with ellipsometry, QCM-D and neutron reflectometry. Aqueous solutions of all samples were characterized with light scattering to determine how the degree of side-group substitution and molecular weight affect the conformation and aggregation of these polymers in the bulk. In addition, hemicellulose samples were studied with SAXS to investigate backbone flexibility. Light scattering results indicated that GM polymers form globular particles while GGMs were found to form rod-like aggregates in the solution. The polysaccharides exhibit higher adsorption to cellulose than on hydrophobic surfaces. A clear correlation between the increase in molecular weight of polysaccharides and increasing adsorbed amount on cellulose was observed, while the adsorbed amount on the hydrophobic surface was fairly independent of the molecular weight. The obtained layer thickness was compared with bulk scattering data and the results indicated flat conformation of the polysaccharides on the surface.

20.
Photochem Photobiol Sci ; 19(10): 1423-1432, 2020 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-32970082

RESUMEN

A series of water soluble 8-alcoxypyrene-1,3,6-trisulfonic sodium salts bearing different alcoxy lateral chains and functional end groups was synthesized and the molecular structure was corroborated by nuclear magnetic resonance spectroscopy. The photophysical properties in water analyzed by UV-Vis and static and dynamic fluorescence revealed that all of the pigments emit in the blue region at a maximal wavelength of 436 nm and with fluorescence lifetimes in the range of ns. Among them, sodium 8-((10-carboxydecyl) oxy) pyrene-1,3,6-trisulfonate M1 exhibits a high fluorescence quantum yield (φ = 80%) and a good interaction with B. subtilis LPM1 rhizobacteria; this has been demonstrated through in vitro staining assays. Tomato plants (Solanum lycopersicon cv. Micro-Tom) increased the release of root exudates, mainly malic and fumaric acids, after 12 h of treatment with benzothiadiazole (BTH) as a foliar elicitor. However, the chemotaxis analysis demonstrated that malic acid is the most powerful chemoattractant of the rhizobacteria Bacillus subtilis LPM1: in agar plates, a major growth (60 mm) was found for a concentration of 100 mM, while in capillary tubes, the earliest response was at 30 min with 3.3 × 108 CFU mL-1. The confocal microscopic analysis carried out on the tomato roots of the pyrene stained B. subtilis LPM1 revealed that this bacterium mainly colonizes the epidermal zones, i.e. the junctions to primary roots, lateral roots and root hairs, meaning that these root hair sections are the highest colonisable sites involved in the biosynthesis of exudates. This fluorescent pyrene marker M1 represents a valuable tool to evaluate B. subtilis-plant interactions in an easy and quick test in both in vitro and in vivo tomato crops.


Asunto(s)
Bacillus subtilis/química , Fluorescencia , Colorantes Fluorescentes/química , Raíces de Plantas/química , Pirenos/análisis , Solanum lycopersicum/microbiología , Colorantes Fluorescentes/síntesis química , Microscopía Confocal , Estructura Molecular , Espectrometría de Fluorescencia
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