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1.
Epidemiology ; 35(3): 377-388, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38567886

RESUMEN

BACKGROUND: Perceptions of the US healthcare system can impact individuals' healthcare utilization, including vaccination intentions. This study examined the association between perceived racial-ethnic inequities in COVID-19 healthcare and willingness to receive the COVID-19 vaccine. METHODS: This study used data from REACH-US, a nationally representative online survey of a large, diverse sample of U.S. adults (N=5145 January 26, 2021-March 3, 2021). Confirmatory factor and regression analyses examined a latent factor of perceived racial-ethnic inequities in COVID-19 healthcare, whether the factor was associated with willingness to receive the COVID-19 vaccine, and whether associations varied across racial-ethnic groups reported as probit estimates (B) and 95% confidence intervals (CIs). RESULTS: Perceived racial-ethnic inequities in COVID-19 healthcare were highest among Black/African American adults (mean latent factor score: 0.65 ± 0.43) and lowest among White adults (mean latent factor score: 0.04 ± 0.67). Black/African American (B = -0.08; 95% CI = -0.19, 0.03) and Native Hawaiian/Pacific Islander (B = -0.08; 95% CI = -0.23, 0.07) adults who perceived greater racial-ethnic inequities in COVID-19 healthcare were less willing than participants who perceived lower inequities. In contrast, American Indian/Alaska Native (B = 0.15; 95% CI = -0.01, 0.30), Asian (B = 0.20; 95% CI = 0.08, 0.31), Hispanic/Latino (English language preference) (B = 0.22; 95% CI = 0.01, 0.43), Multiracial (B = 0.23; 95% CI = 0.09, 0.36), and White (B = 0.31; 95% CI = 0.19, 0.43) adults who perceived greater racial-ethnic inequities in COVID-19 healthcare were more willing to receive the COVID-19 vaccine than participants perceiving higher inequities. CONCLUSIONS: Greater perceived racial-ethnic inequities in COVID-19 healthcare were associated with less willingness to receive the COVID-19 vaccine among Black/African American and Native Hawaiian/Pacific Islander adults.


Asunto(s)
Vacunas contra la COVID-19 , COVID-19 , Disparidades en Atención de Salud , Adulto , Humanos , COVID-19/prevención & control , Vacunas contra la COVID-19/uso terapéutico , Etnicidad , Estados Unidos/epidemiología , Grupos Raciales
2.
BMC Public Health ; 24(1): 1084, 2024 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-38641573

RESUMEN

BACKGROUND: Trust in the healthcare system may impact adherence to recommended healthcare practices, including willingness to test for and vaccinate against COVID-19. This study examined racial/ethnic differences in the associations between trust in the U.S. healthcare system and willingness to test for and vaccinate against COVID-19 during the first year of the pandemic. METHODS: This cross-sectional study used data from the REACH-US study, a nationally representative online survey conducted among a diverse sample of U.S. adults from January 26, 2021-March 3, 2021 (N = 5,121). Multivariable logistic regression estimated the associations between trust in the U.S. healthcare system (measured as "Always", "Most of the time", "Sometimes/Almost Never", and "Never") and willingness to test for COVID-19, and willingness to receive the COVID-19 vaccine. Racial/ethnic differences in these associations were examined using interaction terms and multigroup analyses. RESULTS: Always trusting the U.S. healthcare system was highest among Hispanic/Latino Spanish Language Preference (24.9%) and Asian (16.7%) adults and lowest among Multiracial (8.7%) and Black/African American (10.7%) adults. Always trusting the U.S. healthcare system, compared to never, was associated with greater willingness to test for COVID-19 (AOR: 3.20, 95% CI: 2.38-4.30) and greater willingness to receive the COVID-19 vaccine (AOR: 2.68, 95% CI: 1.97-3.65). CONCLUSIONS: Trust in the U.S. healthcare system was associated with greater willingness to test for COVID-19 and receive the COVID-19 vaccine, however, trust in the U.S. healthcare system was lower among most marginalized racial/ethnic groups. Efforts to establish a more equitable healthcare system that increases trust may encourage COVID-19 preventive behaviors.


Asunto(s)
COVID-19 , Hispánicos o Latinos , Adulto , Humanos , COVID-19/prevención & control , Vacunas contra la COVID-19/uso terapéutico , Estudios Transversales , Disparidades en Atención de Salud , Confianza , Vacunación , Blanco , Negro o Afroamericano , Asiático , Grupos Raciales
3.
Brain Behav Immun ; 109: 144-161, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36702234

RESUMEN

In the last two decades, microglia have emerged as key contributors to disease progression in many neurological disorders, not only by exerting their classical immunological functions but also as extremely dynamic cells with the ability to modulate synaptic and neural activity. This dynamic behavior, together with their heterogeneous roles and response to diverse perturbations in the brain parenchyma has raised the idea that microglia activation is more diverse than anticipated and that understanding the molecular mechanisms underlying microglial states is essential to unravel their role in health and disease from development to aging. The Ikzf1 (a.k.a. Ikaros) gene plays crucial roles in modulating the function and maturation of circulating monocytes and lymphocytes, but whether it regulates microglial functions and states is unknown. Using genetic tools, here we describe that Ikzf1 is specifically expressed in the adult microglia in brain regions such as cortex and hippocampus. By characterizing the Ikzf1 deficient mice, we observed that these mice displayed spatial learning deficits, impaired hippocampal CA3-CA1 long-term potentiation, and decreased spine density in pyramidal neurons of the CA1, which correlates with an increased expression of synaptic markers within microglia. Additionally, these Ikzf1 deficient microglia exhibited a severe abnormal morphology in the hippocampus, which is accompanied by astrogliosis, an aberrant composition of the inflammasome, and an altered expression of disease-associated microglia molecules. Interestingly, the lack of Ikzf1 induced changes on histone 3 acetylation and methylation levels in the hippocampus. Since the lack of Ikzf1 in mice appears to induce the internalization of synaptic markers within microglia, and severe gliosis we then analyzed hippocampal Ikzf1 levels in several models of neurological disorders. Ikzf1 levels were increased in the hippocampus of these neurological models, as well as in postmortem hippocampal samples from Alzheimer's disease patients. Finally, over-expressing Ikzf1 in cultured microglia made these cells hyporeactive upon treatment with lipopolysaccharide, and less phagocytic compared to control microglia. Altogether, these results suggest that altered Ikzf1 levels in the adult hippocampus are sufficient to induce synaptic plasticity and memory deficits via altering microglial state and function.


Asunto(s)
Hipocampo , Microglía , Ratones , Animales , Microglía/metabolismo , Hipocampo/metabolismo , Plasticidad Neuronal/fisiología , Potenciación a Largo Plazo/fisiología , Inflamación/metabolismo
4.
BMC Public Health ; 22(1): 2458, 2022 12 31.
Artículo en Inglés | MEDLINE | ID: mdl-36585651

RESUMEN

College students are often reluctant to follow U.S. preventive guidelines to lower their risk of COVID-19 infection, despite an increased risk of transmission in college settings. Prior research suggested that college students who perceived greater COVID-19 severity and susceptibility (i.e., COVID-19 threat) were more likely to engage in COVID-19 preventive behaviors, yet there is limited research examining whether perceived COVID-19 threat, perceived U.S. healthcare system inequities, and personal experiences of healthcare discrimination collectively influence college students' COVID-19 preventive behaviors. This study identified latent classes of perceived COVID-19 threat, perceived U.S. healthcare system inequities, and personal experiences of healthcare discrimination, examined whether latent classes were associated with COVID-19 preventive behavioral intentions, and assessed whether latent class membership varied across racial/ethnic groups.Students from the University of Maryland, College Park (N = 432) completed the Weighing Factors in COVID-19 Health Decisions survey (December 2020-December 2021). Latent class analysis identified latent classes based on perceived COVID-19 threat, perceived U.S. healthcare system inequities, and personal experiences of healthcare discrimination. Regression analyses examined associations between the latent classes and COVID-19 preventive behavioral intentions (i.e., social distancing, mask-wearing, COVID-19 vaccination) and whether latent class membership varied across racial/ethnic groups.Students in Latent Class 1 (27.3% of the sample) had high perceived COVID-19 threat and U.S. healthcare system inequities and medium probability of experiencing personal healthcare discrimination. Students in Latent Class 1 had higher social distancing, mask-wearing, and vaccination intentions compared to other latent classes. Compared to Latent Class 4 (reference group), students in Latent Class 1 had higher odds of identifying as Hispanic or Latino, Non-Hispanic Asian, Non-Hispanic Black or African American, and Non-Hispanic Multiracial versus Non-Hispanic White.Latent classes of higher perceived COVID-19 threat, perceived U.S. healthcare system inequities, and personal experiences of healthcare discrimination were associated with higher COVID-19 preventive behavioral intentions and latent class membership varied across racial/ethnic groups. Interventions should emphasize the importance of COVID-19 preventive behaviors among students who perceive lower COVID-19 threat.


Asunto(s)
Vacunas contra la COVID-19 , COVID-19 , Humanos , Intención , COVID-19/epidemiología , COVID-19/prevención & control , Estudiantes , Disparidades en Atención de Salud
6.
New Phytol ; 221(2): 850-865, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30192000

RESUMEN

Chloroplasts retain part of their ancestral genomes and the machinery for expression of those genomes. The nucleus-encoded chloroplast RNA helicase INCREASED SIZE EXCLUSION LIMIT2 (ISE2) is required for chloroplast ribosomal RNA processing and chloro-ribosome assembly. To further elucidate ISE2's role in chloroplast translation, two independent approaches were used to identify its potential protein partners. Both a yeast two-hybrid screen and a pull-down assay identified plastid ribosomal protein L15, uL15c (formerly RPL15), as interacting with ISE2. The interaction was confirmed in vivo by co-immunoprecipitation. Interestingly, we found that rpl15 null mutants do not complete embryogenesis, indicating that RPL15 is an essential gene for autotrophic growth of Arabidopsis thaliana. Arabidopsis and Nicotiana benthamiana plants with reduced expression of RPL15 developed chlorotic leaves, had reduced photosynthetic capacity and exhibited defective chloroplast development. Processing of chloroplast ribosomal RNAs and assembly of ribosomal subunits were disrupted by reduced expression of RPL15. Chloroplast translation was also decreased, reducing accumulation of chloroplast-encoded proteins, in such plants compared to wild-type plants. Notably, knockdown of RPL15 expression increased intercellular trafficking, a phenotype also observed in plants with reduced ISE2 expression. This finding provides further evidence for chloroplast function in modulating intercellular trafficking via plasmodesmata.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Arabidopsis/genética , Proteínas de Cloroplastos/metabolismo , ARN Helicasas/metabolismo , Proteínas Ribosómicas/metabolismo , Arabidopsis/fisiología , Arabidopsis/ultraestructura , Proteínas de Arabidopsis/genética , Proteínas de Cloroplastos/genética , Cloroplastos/metabolismo , Cloroplastos/ultraestructura , Genes Reporteros , Fotosíntesis , Plasmodesmos/metabolismo , Transporte de Proteínas , ARN Helicasas/genética , ARN del Cloroplasto/genética , ARN Ribosómico/genética , Proteínas Ribosómicas/genética , Nicotiana/genética , Nicotiana/fisiología , Nicotiana/ultraestructura
7.
Plant Physiol ; 176(1): 910-929, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-29158332

RESUMEN

Ethylene is a gaseous plant hormone perceived by a family of receptors in Arabidopsis (Arabidopsis thaliana) including ETHYLENE RESPONSE1 (ETR1) and ETR2. Previously we showed that etr1-6 loss-of-function plants germinate better and etr2-3 loss-of-function plants germinate worse than wild-type under NaCl stress and in response to abscisic acid (ABA). In this study, we expanded these results by showing that ETR1 and ETR2 have contrasting roles in the control of germination under a variety of inhibitory conditions for seed germination such as treatment with KCl, CuSO4, ZnSO4, and ethanol. Pharmacological and molecular biology results support a model where ETR1 and ETR2 are indirectly affecting the expression of genes encoding ABA signaling proteins to affect ABA sensitivity. The receiver domain of ETR1 is involved in this function in germination under these conditions and controlling the expression of genes encoding ABA signaling proteins. Epistasis analysis demonstrated that these contrasting roles of ETR1 and ETR2 do not require the canonical ethylene signaling pathway. To explore the importance of receptor-protein interactions, we conducted yeast two-hybrid screens using the cytosolic domains of ETR1 and ETR2 as bait. Unique interacting partners with either ETR1 or ETR2 were identified. We focused on three of these proteins and confirmed the interactions with receptors. Loss of these proteins led to faster germination in response to ABA, showing that they are involved in ABA responses. Thus, ETR1 and ETR2 have both ethylene-dependent and -independent roles in plant cells that affect responses to ABA.


Asunto(s)
Ácido Abscísico/metabolismo , Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Etilenos/metabolismo , Receptores de Superficie Celular/metabolismo , Transducción de Señal , Ácido Abscísico/farmacología , Arabidopsis/efectos de los fármacos , Arabidopsis/genética , Proteínas de Arabidopsis/química , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Germinación/efectos de los fármacos , Mutación/genética , Unión Proteica/efectos de los fármacos , ARN Mensajero/genética , ARN Mensajero/metabolismo , Receptores de Superficie Celular/química , Semillas/efectos de los fármacos , Semillas/crecimiento & desarrollo , Transducción de Señal/genética , Transgenes , Técnicas del Sistema de Dos Híbridos
8.
Int J Mol Sci ; 20(7)2019 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-30965663

RESUMEN

Small fish are an excellent experimental model to screen endocrine-disrupting compounds, but current fish-based assays to detect endocrine disruption have not been standardized yet, meaning that there is not consensus on endpoints and biomarkers to be measured. Moreover, exposure conditions may vary depending on the species used as the experimental model and the endocrine pathway evaluated. At present, a battery of a wide range of assays is usually needed for the complete assessment of endocrine activities. With the aim of providing a simple, robust, and fast assay to assess endocrine-disrupting potencies for the three major endocrine axes, i.e., estrogens, androgens, and thyroid, we propose the use of a panel of eight gene expression biomarkers in zebrafish larvae. This includes brain aromatase (cyp19a1b) and vitellogenin 1 (vtg1) for estrogens, cytosolic sulfotransferase 2 family 2 (sult2st3) and cytochrome P450 2k22 (cyp2k22) for androgens, and thyroid peroxidase (tpo), transthyretin (ttr), thyroid receptor α (trα), and iodothyronine deiodinase 2 (dio2) for thyroid metabolism. All of them were selected according to their responses after exposure to the natural ligands 17ß-estradiol, testosterone, and 3,3',5-triiodo-L-thyronine (T3), respectively, and subsequently validated using compounds reported as endocrine disruptors in previous studies. Cross-talk effects were also evaluated for all compounds.


Asunto(s)
Bioensayo/métodos , Disruptores Endocrinos/toxicidad , Transcriptoma/genética , Andrógenos/análisis , Animales , Sistema Endocrino/efectos de los fármacos , Sistema Endocrino/metabolismo , Estrógenos/análisis , Regulación del Desarrollo de la Expresión Génica/efectos de los fármacos , Regulación del Desarrollo de la Expresión Génica/genética , Pez Cebra
9.
Plant J ; 91(1): 114-131, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28346704

RESUMEN

INCREASED SIZE EXCLUSION LIMIT2 (ISE2) is a chloroplast-localized RNA helicase that is indispensable for proper plant development. Chloroplasts in leaves with reduced ISE2 expression have previously been shown to exhibit reduced thylakoid contents and increased stromal volume, indicative of defective development. It has recently been reported that ISE2 is required for the splicing of group II introns from chloroplast transcripts. The current study extends these findings, and presents evidence for ISE2's role in multiple aspects of chloroplast RNA processing beyond group II intron splicing. Loss of ISE2 from Arabidopsis thaliana leaves resulted in defects in C-to-U RNA editing, altered accumulation of chloroplast transcripts and chloroplast-encoded proteins, and defective processing of chloroplast ribosomal RNAs. Potential ISE2 substrates were identified by RNA immunoprecipitation followed by next-generation sequencing (RIP-seq), and the diversity of RNA species identified supports ISE2's involvement in multiple aspects of chloroplast RNA metabolism. Comprehensive phylogenetic analyses revealed that ISE2 is a non-canonical Ski2-like RNA helicase that represents a separate sub-clade unique to green photosynthetic organisms, consistent with its function as an essential protein. Thus ISE2's evolutionary conservation may be explained by its numerous roles in regulating chloroplast gene expression.


Asunto(s)
Arabidopsis/enzimología , Arabidopsis/metabolismo , ARN Helicasas/metabolismo , ARN del Cloroplasto/metabolismo , Arabidopsis/genética , Cloroplastos/genética , Cloroplastos/metabolismo , Regulación de la Expresión Génica de las Plantas , Intrones/genética , Plasmodesmos/metabolismo , Edición de ARN/genética , ARN Helicasas/genética
10.
Appetite ; 128: 321-332, 2018 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-29902503

RESUMEN

The mechanisms that lead to overeating and the consumption of tempting, unhealthy foods have been studied extensively, but the compensatory actions taken afterwards have not. Here we describe the naïve models individuals hold around dietary splurges (single bouts of overeating) and associated weight changes. Across six online experiments, we found that, following a hypothetical dietary splurge, participants did not plan to adequately adjust calorie consumption to account for the additional calories consumed (Studies 1 and 2), and this pattern was worse following hypothetical splurges characterized by a large amount of food consumed in a single bout (Study 3). Participants expected weight changes to happen faster than they do in reality (Study 4) and they expected that weight gained from a dietary splurge would disappear on its own without explicit compensation attempts through diet or exercise (Study 5). Similarly, participants expected that when compensation attempts were made through calorie restriction, the rate of weight loss would be faster following a dietary splurge compared to normal eating (Study 6). This research contributes novel data demonstrating an important mechanism that likely contributes to weight gain and failed weight loss attempts.


Asunto(s)
Restricción Calórica/psicología , Dieta/psicología , Conducta Alimentaria/psicología , Hiperfagia/psicología , Aumento de Peso , Adulto , Dieta/métodos , Femenino , Humanos , Hiperfagia/fisiopatología , Masculino , Factores de Tiempo , Pérdida de Peso
11.
J Am Chem Soc ; 137(36): 11666-77, 2015 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-26332445

RESUMEN

Exerting control over the near-infrared (NIR) plasmonic response of nanosized metals and semiconductors can facilitate access to unexplored phenomena and applications. Here we combine electrostatic self-assembly and Cd(2+)/Cu(+) cation exchange to obtain an anisotropic core-shell nanoparticle cluster (NPC) whose optical properties stem from two dissimilar plasmonic materials: a gold nanorod (AuNR) core and a copper selenide (Cu(2-x)Se, x ≥ 0) supraparticle shell. The spectral response of the AuNR@Cu2Se NPCs is governed by the transverse and longitudinal plasmon bands (LPB) of the anisotropic metallic core, since the Cu2Se shell is nonplasmonic. Under aerobic conditions the shell undergoes vacancy doping (x > 0), leading to the plasmon-rich NIR spectrum of the AuNR@Cu(2-x)Se NPCs. For low vacancy doping levels the NIR optical properties of the dually plasmonic NPCs are determined by the LPBs of the semiconductor shell (along its major longitudinal axis) and of the metal core. Conversely, for high vacancy doping levels their NIR optical response is dominated by the two most intense plasmon modes from the shell: the transverse (along the shortest transversal axis) and longitudinal (along the major longitudinal axis) modes. The optical properties of the NPCs can be reversibly switched back to a purely metallic plasmonic character upon reversible conversion of AuNR@Cu(2-x)Se into AuNR@Cu2Se. Such well-defined nanosized colloidal assemblies feature the unique ability of holding an all-metallic, a metallic/semiconductor, or an all-semiconductor plasmonic response in the NIR. Therefore, they can serve as an ideal platform to evaluate the crosstalk between plasmonic metals and plasmonic semiconductors at the nanoscale. Furthermore, their versatility to display plasmon modes in the first, second, or both NIR windows is particularly advantageous for bioapplications, especially considering their strong absorbing and near-field enhancing properties.

12.
Small ; 11(35): 4550-9, 2015 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-26068971

RESUMEN

Branched gold nanoparticles with sharp tips are considered excellent candidates for sensing and field enhancement applications. Here, a rapid and simple synthesis strategy is presented that generates highly branched gold nanoparticles with hollow cores and a ca.100% yield through a simple one-pot seedless reaction at room temperature in the presence of Triton X-100. It is shown that multibranched hollow gold nanoparticles of tunable dimensions, branch density and branch length can be obtained by adjusting the concentrations of the reactants. Insights into the formation mechanism point toward an aggregative type of growth involving hollow core formation first, and branching thereafter. The pronounced near-infrared (NIR) plasmon band of the nanoparticles is due to the combined contribution from hollowness and branching, and can be tuned over a wide range (≈700-2000 nm). It is also demonstrated that the high environmental sensitivity of colloidal dispersions based on multibranched hollow gold nanoparticles can be boosted even further by separating the nanoparticles into fractions of given sizes and improved monodispersity by means of a glycerol density gradient. The possibility to obtain highly monodisperse multibranched hollow gold nanoparticles with predictable dimensions (50-300 nm) and branching and, therefore, tailored NIR plasmonic properties, highlights their potential for theranostic applications.

13.
J Reprod Med ; 59(5-6): 209-12, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24937959

RESUMEN

OBJECTIVE: To determine the time of human chorionic gonadotropin (hCG) regression in nonmolar gestation. STUDY DESIGN: Patients treated at our institution between June 2012 and July 2013 were selected by a deterministic sequential sampling distributed among 2 phases. Distribution of the patients included resolved cases by vaginal delivery and cesarean section in preterm and term pregnancies, ectopic, and abortion. Phase 1: serum hCG values were determined at 4, 5 and 6 weeks of obstetric resolution. Phase 2: hCG serum values were determined immediately at obstetric resolution and at 2, 3 and 4 weeks of the resolution of the cases, too. RESULTS: Phase 1: After the analysis of serum hCG of 63 patients at 4, 5 and 6 weeks postresolution, a negative result was corroborated in 100% of cases, in any period of the sample, with average values of 1.71, 0.55, and 0.18 mIU/mL, respectively. Phase 2 included 398 patients, with serum hCG in the first 72 hours postresolution, showing an average hCG value of 1,483.5 mIU/mL (range, 0.07-10,789), noting that 1% of cases had negative results. We then obtained hCG values at 2, 3 and 4 weeks of resolution, showing the regression in 73.4% of cases in the 2nd week, in 96.7% of patients in the 3rd week, and in all cases in the 4th week. CONCLUSION: The regression of hCG after nonmolar pregnancy does not exceed 3 weeks.


Asunto(s)
Gonadotropina Coriónica/sangre , Aborto Espontáneo/sangre , Adolescente , Adulto , Cesárea , Parto Obstétrico , Femenino , Edad Gestacional , Enfermedad Trofoblástica Gestacional/sangre , Humanos , Embarazo , Embarazo Ectópico/sangre , Nacimiento Prematuro/sangre , Factores de Tiempo
14.
Cells ; 13(4)2024 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-38391962

RESUMEN

Optimising drug delivery to tumours remains an obstacle to effective cancer treatment. A prerequisite for successful chemotherapy is that the drugs reach all tumour cells. The vascular network of tumours, extravasation across the capillary wall and penetration throughout the extracellular matrix limit the delivery of drugs. Ultrasound combined with microbubbles has been shown to improve the therapeutic response in preclinical and clinical studies. Most studies apply microbubbles designed as ultrasound contrast agents. Acoustic Cluster Therapy (ACT®) is a novel approach based on ultrasound-activated microbubbles, which have a diameter 5-10 times larger than regular contrast agent microbubbles. An advantage of using such large microbubbles is that they are in contact with a larger part of the capillary wall, and the oscillating microbubbles exert more effective biomechanical effects on the vessel wall. In accordance with this, ACT® has shown promising therapeutic results in combination with various drugs and drug-loaded nanoparticles. Knowledge of the mechanism and behaviour of drugs and microbubbles is needed to optimise ACT®. Real-time intravital microscopy (IVM) is a useful tool for such studies. This paper presents the experimental setup design for visualising ACT® microbubbles within the vasculature of tumours implanted in dorsal window (DW) chambers. It presents ultrasound setups, the integration and alignment of the ultrasound field with the optical system in live animal experiments, and the methodologies for visualisation and analysing the recordings. Dextran was used as a fluorescent marker to visualise the blood vessels and to trace drug extravasation and penetration into the extracellular matrix. The results reveal that the experimental setup successfully recorded the kinetics of extravasation and penetration distances into the extracellular matrix, offering a deeper understanding of ACT's mechanisms and potential in localised drug delivery.


Asunto(s)
Neoplasias , Animales , Ultrasonografía , Neoplasias/tratamiento farmacológico , Acústica , Medios de Contraste , Microscopía Intravital
15.
PLoS One ; 19(2): e0290505, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38359055

RESUMEN

Coral reefs are the most diverse ecosystem on the planet based on the abundance and diversity of phyla and higher taxa. However, it is still difficult to assess the diversity of lower taxa, especially at the species level. One tool for improving the identification of lower taxa are genetic markers that can distinguish cryptic species and assess species boundaries. Here, we present one such approach for an important and challenging group of reef-building corals. Porites corals are the main reef-builders of many coral reefs in the Indo-Pacific, owing to the massive growth forms of some species. The current number of valid Porites species is controversial, inflated with many synonymies, and often based on gross colony morphology although several morphospecies believed to be widespread and common can only be distinguished based on detailed microstructure analyses by taxonomic experts. Here, we test the suitability of multiple regions of mtDNA as genetic barcodes to identify suitable markers for species differentiation and unambiguous identification. Resulting sequencing data was further used for the first phylogenetic analysis of Guam's Porites species. We tested eight different mitochondrial markers and analyzed four in detail for 135 Porites specimens: mtDNA markers were amplified for 67 Porites specimens from Guam, representing 12 nominal Porites species, and combined with 69 mitochondrial genomes, mostly from Hawaii. The combination of all 4 markers distinguished 10 common and 7 uncommon Central-West Pacific Porites species. Most clades separate species along taxonomic boundaries, which is uncommon for Porites corals and testifies to the suitability of our multi-marker approach, and a combination of the two most promising barcodes distinguished 8/10 common species. These barcodes are thus suitable to distinguish virtually cryptic species in one of the most important and challenging coral genera. They offer a cheap, fast and reliable way to identify Porites species for species-level research, monitoring and conservation.


Asunto(s)
Antozoos , Animales , Antozoos/genética , Filogenia , Ecosistema , Arrecifes de Coral , ADN Mitocondrial
16.
Dis Model Mech ; 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38903015

RESUMEN

Structural changes to vocal fold (VF) epithelium, namely loosened intercellular junctions have been reported in VF benign lesions. Potential mechanisms responsible for the disruption of cell junctions do not address the contribution of resident microbial communities to this pathological phenomenon. In this study, we focused on determining the relationship between Streptococcus pseudopneumoniae (SP), a dominant bacterial species associated with benign lesions, and S. salivarius (SS), a commensal bacterium, with human VF epithelial cells, in our three-dimensional model of human VF mucosa. This experimental system enabled direct deposition of bacteria onto constructs at the Air/Liquid interface allowing for the assessment of bacteria-host interactions at cellular, molecular and ultrastructural levels. Our findings demonstrate that SP disrupts VF epithelial integrity and initiates inflammation via exported products, HtrA1 and pneumolysin. In contrast, SS attaches to VF epithelium, reduces inflammation and induces Mmp2-mediated apical desquamation of infected cells to mitigate the impact of pathogens. In conclusion, this study highlights the complexity of microbial involvement in VF pathology and potential VF mucosal restoration in the presence of laryngeal commensals.

17.
JAMA Netw Open ; 7(5): e2412880, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38819825

RESUMEN

Importance: Screening for lung cancer using low-dose computed tomography is associated with reduced lung cancer-specific mortality, but uptake is low in the US; understanding how patients make decisions to engage with lung cancer screening is critical for increasing uptake. Prior research has focused on individual-level psychosocial factors, but environmental factors (eg, historical contexts that include experiencing racism) and modifying factors-those that can be changed to make it easier or harder to undergo screening-also likely affect screening decisions. Objective: To investigate environmental, psychosocial, and modifying factors influencing lung cancer screening decision-making and develop a conceptual framework depicting relationships between these factors. Design, Setting, and Participants: This multimethod qualitative study was conducted from December 2021 to June 2022 using virtual semistructured interviews and 4 focus groups (3-4 participants per group). All participants met US Preventive Services Task Force eligibility criteria for lung cancer screening (ie, age 50-80 years, at least a 20 pack-year smoking history, and either currently smoke or quit within the past 15 years). Screening-eligible US participants were recruited using an online panel. Main Outcomes and Measures: Key factors influencing screening decisions (eg, knowledge, beliefs, barriers, and facilitators) were the main outcome. A theory-informed, iterative inductive-deductive approach was applied to analyze data and develop a conceptual framework summarizing results. Results: Among 34 total participants (interviews, 20 [59%]; focus groups, 14 [41%]), mean (SD) age was 59.1 (4.8) years and 20 (59%) identified as female. Half had a household income below $20 000 (17 [50%]). Participants emphasized historical and present-day racism as critical factors contributing to mistrust of health care practitioners and avoidance of medical procedures like screening. Participants reported that other factors, such as public transportation availability, also influenced decisions. Additionally, participants described psychosocial processes involved in decisions, such as perceived screening benefits, lung cancer risk appraisal, and fear of a cancer diagnosis or harmful encounters with practitioners. In addition, participants identified modifying factors (eg, insurance coverage) that could make receiving screening easier or harder. Conclusions and Relevance: In this qualitative study of patient lung cancer screening decisions, environmental, psychosocial, and modifying factors influenced screening decisions. The findings suggest that systems-level interventions, such as those that help practitioners understand and discuss patients' prior negative health care experiences, are needed to promote effective screening decision-making.


Asunto(s)
Toma de Decisiones , Detección Precoz del Cáncer , Neoplasias Pulmonares , Investigación Cualitativa , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/psicología , Femenino , Masculino , Persona de Mediana Edad , Detección Precoz del Cáncer/psicología , Detección Precoz del Cáncer/métodos , Anciano , Grupos Focales , Anciano de 80 o más Años , Tomografía Computarizada por Rayos X/psicología , Estados Unidos
18.
BMC Psychiatry ; 13: 229, 2013 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-24053640

RESUMEN

BACKGROUND: The Scale to Assess Unawareness in Mental Disorder (SUMD) is widely used in clinical trials and epidemiological studies but more rarely in clinical practice because of its length (74 items). In clinical practice, it is necessary to provide shorter instruments. The aim of this study was to investigate the validity and reliability of the abbreviated version of the SUMD. DESIGN: We used data from four cross-sectional studies conducted in several psychiatric hospitals in France. INCLUSION CRITERIA: a diagnosis of schizophrenia based on DSM-IV criteria. DATA COLLECTION: socio-demographic and clinical data (including duration of illness, Positive and Negative Syndrome Scale, and the Calgary Depression Scale); quality of life; SUMD. STATISTICAL ANALYSIS: confirmatory factor analyses, item-dimension correlations, Cronbach's alpha coefficients, Rasch statistics, relationships between the SUMD and other parameters. We tested two different scoring models and considered the response 'not applicable' as '0' or as missing data. RESULTS: Five hundred and thirty-one patients participated in this study. The 3-factor structure of the SUMD (awareness of the disease, consequences and need for treatment; awareness of positive symptoms; and awareness of negative symptoms) was confirmed using LISREL confirmatory factor analysis for the two models. Internal item consistency and reliability were satisfactory for all dimensions. External validity testing revealed that dimension scores correlated significantly with all PANSS scores, especially with the G12 item (lack of judgement and awareness). Significant associations with age, disease duration, education level, and living arrangements showed good discriminant validity. CONCLUSION: The abbreviated version of the SUMD appears to be a valid and reliable instrument for measuring insight in patients with schizophrenia and may be used by clinicians to accurately assess insight in clinical settings.


Asunto(s)
Concienciación , Esquizofrenia/diagnóstico , Psicología del Esquizofrénico , Adulto , Estudios Transversales , Bases de Datos Factuales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Escalas de Valoración Psiquiátrica , Psicometría , Reproducibilidad de los Resultados , Encuestas y Cuestionarios
19.
Nano Lett ; 12(9): 5008-13, 2012 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-22924473

RESUMEN

Designing nanoscale objects with the potential to perform externally controlled motion in biological environments is one of the most sought-after objectives in nanotechnology. Different types of chemically and physically powered motors have been prepared at the macro- and microscale. However, the preparation of nanoscale objects with a complex morphology, and the potential for light-driven motion has remained elusive to date. Here, we go a step forward by designing a nanoscale hybrid with a propeller-resembling shape, which can be controlled by focused light under biological conditions. Our hybrid, hereafter "Au@DNA-origami", consists of a spherical gold nanoparticle with self-assembled, biocompatible, two-dimensional (2D) DNA sheets on its surface. As a first step toward the potential utilization of these nanoscale objects as light-driven assemblies in biological environments, we show that they can be optically trapped, and hence translated and deposited on-demand, and that under realistic trapping conditions the thermally induced dehybridization of the DNA sheets can be avoided.


Asunto(s)
Materiales Biocompatibles/síntesis química , Cristalización/métodos , ADN/química , ADN/ultraestructura , Nanoestructuras/química , Nanoestructuras/ultraestructura , Pinzas Ópticas , Sustancias Macromoleculares/química , Ensayo de Materiales , Conformación Molecular , Tamaño de la Partícula , Propiedades de Superficie
20.
Nano Lett ; 12(8): 4172-80, 2012 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-22746278

RESUMEN

Imaging localized plasmon modes in noble-metal nanoparticles is of fundamental importance for applications such as ultrasensitive molecular detection. Here, we demonstrate the combined use of optical dark-field microscopy (DFM), cathodoluminescence (CL), and electron energy-loss spectroscopy (EELS) to study localized surface plasmons on individual gold nanodecahedra. By exciting surface plasmons with either external light or an electron beam, we experimentally resolve a prominent dipole-active plasmon band in the far-field radiation acquired via DFM and CL, whereas EELS reveals an additional plasmon mode associated with a weak dipole moment. We present measured spectra and intensity maps of plasmon modes in individual nanodecahedra in excellent agreement with boundary-element method simulations, including the effect of the substrate. A simple tight-binding model is formulated to successfully explain the rich plasmon structure in these particles encompasing bright and dark modes, which we predict to be fully observable in less lossy silver decahedra. Our work provides useful insight into the complex nature of plasmon resonances in nanoparticles with pentagonal symmetry.

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