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1.
Eur J Neurosci ; 58(1): 2267-2277, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37165756

RESUMEN

Galvanic vestibular stimulation (GVS) helps stabilize subjects when balance and posture are compromised. This work aimed to define the cortical regions that GVS activates in normal subjects. We used functional near-infrared spectroscopy (fNIRS) to test the hypothesis that GVS activates similar cortical areas as a passive movement. We used transcranial current stimulation (cathode in the right mastoid process and anode in the FPz frontopolar point) of bipolar direct current (2 mA), false GVS (sham), vibration (neutral stimulus), and back and forth motion (positive control of vestibular movement) in 18 clinically healthy volunteers. Seventy-two brain scans were performed, applying a crossover-type experimental design. We measured the heart rate, blood pressure, body temperature, head capacitance, and resistance before and after the experiment. The haemodynamic changes of the cerebral cortex were recorded with an arrangement of 26 channels in four regions to perform an ROI-level analysis. The back-and-forth motion produced the most significant oxygenated haemoglobin (HbO2 ) increase. The response was similar for the GVS stimulus on the anterior and posterior parietal and right temporal regions. Sham and vibrational conditions did not produce significant changes ROI-wise. The results indicate that GVS produces a cortical activation coherent with displacement percept.


Asunto(s)
Espectroscopía Infrarroja Corta , Vestíbulo del Laberinto , Humanos , Lóbulo Temporal , Corteza Cerebral/fisiología , Vestíbulo del Laberinto/fisiología , Neuroimagen , Estimulación Eléctrica/métodos
2.
J Gen Virol ; 104(11)2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37910165

RESUMEN

Human astroviruses (HAstVs) are small, non-enveloped icosahedral RNA viruses that are a significant cause of diarrhoea in young children. Despite their worldwide prevalence, HAstV pathogenesis studies and vaccine development remain challenging due to the lack of an animal model for HAstV infection. The recent development of a murine astrovirus (MuAstV) infection model in mice provides the opportunity to test proof-of-concept vaccines based on MuAstV antigens. To help establish a system in which an astrovirus capsid spike-based vaccine could be tested in vivo, we designed and produced a recombinant MuAstV capsid spike protein based on predicted secondary structure homology to HAstV spike proteins. The recombinant MuAstV spike can be expressed with high efficiency in Escherichia coli and retains antigenicity to polyclonal antibodies elicited by MuAstV infection. We determined the crystal structure of the MuAstV spike to 1.75 Å and assessed its structural conservation with HAstV capsid spike. Despite low sequence identity between the MuAstV and HAstV spikes and differences in their overall shapes, they share related structural folds. Additionally, we found that vaccination with MuAstV spike induced anti-MuAstV-spike antibodies, highlighting that the recombinant spike is immunogenic. These studies lay a foundation for future in vivo MuAstV challenge studies to test whether MuAstV spike can be the basis of an effective vaccine.


Asunto(s)
Infecciones por Astroviridae , Astroviridae , Vacunas , Niño , Humanos , Animales , Ratones , Preescolar , Cápside , Proteínas de la Cápside/genética
3.
Exp Brain Res ; 241(6): 1555-1567, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37127798

RESUMEN

Older adults with Type II Diabetes Mellitus (DM) experience mild cognitive impairment, specifically in the domain of recall/working memory. No consistent causative structural cortical deficits have been identified in persons with DM (PwDM). Memory deficits may be exacerbated in older adult females, who are at the highest risk of cardiovascular decline due to DM. The focus of the current study was to evaluate functional cortical hemodynamic activity during memory tasks in postmenopausal PwDM. Functional Near Infrared Spectroscopy (fNIRS) was used to monitor oxyhemoglobin (HbO) and deoxyhemoglobin (HbR) during memory-based tasks in a cross-sectional sample of postmenopausal women with DM. Twenty-one community-dwelling DM females (age = 65 ± 6 years) and twenty-one age- and sex-matched healthy controls (age = 66 ± 6 years) were evaluated. Working memory performance (via N-back) was evaluated while study participants donned cortical fNIRS. Health state, metabolic data, and menopausal status data were also collected. Deficits in working memory accuracy were found in the DM group as compared to controls. Differences in HbO responses emerged in the DM group. The DM group exhibited altered PFC activity magnitudes and increased functional cortical activity across ROIs compared to controls. HbO and HbR responses were not associated with worsened health state measures. These data indicate a shift in cortical activity patterns with memory deficits in postmenopausal PwDM. This DM-specific shift of HbO is a novel finding that is unlikely to be detected by fMRI. This underscores the value of using non-MRI-based neuroimaging techniques to evaluate cortical hemodynamic function to detect early mild cognitive impairment.


Asunto(s)
Diabetes Mellitus Tipo 2 , Espectroscopía Infrarroja Corta , Humanos , Femenino , Anciano , Persona de Mediana Edad , Espectroscopía Infrarroja Corta/métodos , Posmenopausia , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/diagnóstico por imagen , Estudios Transversales , Trastornos de la Memoria/diagnóstico por imagen , Trastornos de la Memoria/etiología , Memoria a Corto Plazo/fisiología
4.
Geriatr Nurs ; 54: 135-143, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37782976

RESUMEN

BACKGROUND: Low back pain (LBP) disproportionately affects older black adults, often leading to inadequate treatment due to clinician biases. Objective pain measures are imperative, and Functional Near-Infrared Spectroscopy (fNIRS) shows promise for pain detection. AIM: To determine the impact of listening to home-based preferred web app-based music on underlying pain processing mechanisms at the central nervous level in older black adults aged ≥65 with LBP. METHODS: Twenty older black adults with LBP listened to preferred music twice daily for four days using the MUSIC CARE® app. Neuroimaging data were collected using fNIRS. Data were transformed to changes in oxy-hemoglobin and deoxy-hemoglobin concentrations and analyzed. RESULTS: Significant cortical activation pattern differences were observed between pre-and post-intervention scans, particularly in somatosensory regions. Post-intervention scans showed significantly reduced hemodynamic activities. CONCLUSION: Preferred music listening has the potential to alleviate pain, and fNIRS emerges as a promising tool for exploring cortical-level pain-related neural circuits.


Asunto(s)
Dolor de la Región Lumbar , Aplicaciones Móviles , Música , Humanos , Anciano , Dolor de la Región Lumbar/terapia , Espectroscopía Infrarroja Corta/métodos , Hemoglobinas
5.
Bioorg Chem ; 124: 105872, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35597192

RESUMEN

Leishmaniasis produces approximately-one million of new cases annually, making it one of the most important tropical diseases. As current treatments are not fully effective and are toxic, it is necessary to develop new therapies that are more effective and less toxic, and cause a controlled cell death, with which we can avoid the immunological problems caused by necrosis. In this work 32 acrylonitriles were studied in vitro against Leishmania amazonensis. Three compounds Q20 (12.41), Q29 (11.2) and Q31 (11.56) had better selectivity than the reference compound, miltefosine (11.14) against promastigotes of these parasites, for this reason they were selected to determine their mechanism of action to know the cell death type of they produce. The results of the mechanisms of action show that these three acrylonitriles tested produce chromatin condensation, decreased mitochondrial membrane potential, altered plasma permeability and production of reactive oxygen species. All these characteristic events seem to indicate programmed cell death. Therefore, this study demonstrates the activity of acrylonitriles derivatives as possible leishmanicidal agents.


Asunto(s)
Acrilonitrilo , Antiprotozoarios , Leishmania mexicana , Acrilonitrilo/metabolismo , Acrilonitrilo/farmacología , Animales , Antiprotozoarios/metabolismo , Muerte Celular , Macrófagos , Ratones , Ratones Endogámicos BALB C
6.
Phys Rev Lett ; 126(13): 133002, 2021 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-33861123

RESUMEN

First-principles calculations are employed to elucidate the modes of attosecond charge migration (CM) in halogenated hydrocarbon chains. We use constrained density functional theory (DFT) to emulate the creation of a localized hole on the halogen and follow the subsequent dynamics via time-dependent DFT. We find low-frequency CM modes (∼1 eV) that propagate across the molecule and study their dependence on length, bond order, and halogenation. We observe that the CM speed (∼4 Å/fs) is largely independent of molecule length, but is lower for triple-bonded versus double-bonded molecules. Additionally, as the halogen mass increases, the hole travels in a more particlelike manner as it moves across the molecule. These heuristics will be useful in identifying molecules and optimal CM detection methods for future experiments, especially for halogenated hydrocarbons which are promising targets for ionization-triggered CM.

7.
Dev Psychobiol ; 63(6): e22181, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34423434

RESUMEN

Children reared in socioeconomically disadvantaged environments are at risk for academic, cognitive, and behavioral problems. Mounting evidence suggests that childhood adversities, encountered at disproportionate rates in contexts of socioeconomic risk, shape the developing brain in ways that explain disparities. Circuitries that subserve neurocognitive functions related to memory, attention, and cognitive control are especially affected. However, most work showing altered neural function has focused on middle childhood and adolescence. Understanding alterations in brain development during foundational points in early childhood is a key next step. To address this gap, we examined functional near-infrared-spectroscopy-based neural activation during a working memory (WM) task in young children aged 4-7 years (N = 30) who varied in socioeconomic risk exposure. Children who experienced greater disadvantage (lower income to needs ratio and lower Hollingshead index) exhibited lower activation in the lateral prefrontal cortex than children who experienced less to no disadvantage. Variability in prefrontal cortex activation, but not behavioral performance on the WM task, was associated with worse executive functioning in children as reported by parents. These findings add to existing evidence that exposure to early adversity, such as socioeconomic risk, may lead to foundational changes in the developing brain, which increases risk for disparities in functioning across multiple cognitive and social domains.


Asunto(s)
Memoria a Corto Plazo , Corteza Prefrontal , Adolescente , Atención/fisiología , Niño , Preescolar , Función Ejecutiva/fisiología , Humanos , Memoria a Corto Plazo/fisiología , Corteza Prefrontal/fisiología , Factores Socioeconómicos
8.
Molecules ; 26(14)2021 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-34299395

RESUMEN

A novel organocatalytic multicomponent cyanovinylation of aldehydes was designed for the synthesis of conjugated cyanomethyl vinyl ethers. The reaction was implemented for the synthesis of a 3-substituted 3-(cyanomethoxy)acrylates, using aldehydes as substrates, acetone cyanohydrin as the cyanide anion source, and methyl propiolate as the source of the vinyl component. The multicomponent reaction is catalyzed by N-methyl morpholine (2.5 mol%) to deliver the 3-(cyanomethoxy)acrylates in excellent yields and with preponderance of the E-isomer. The multicomponent reaction manifold is highly tolerant to the structure and composition of the aldehyde (aliphatic, aromatic, heteroaromatics), and it is instrumentally simple (one batch, open atmospheres), economic (2.5 mol% catalyst, stoichiometric reagents), environmentally friendly (no toxic waste), and sustainable (easy scalability).

9.
Entropy (Basel) ; 22(9)2020 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-33286704

RESUMEN

A modified expression of the electron entropy production in a plasma is deduced by means of the Kelly equations of state instead of the ideal gas equations of state. From the Debye-Hückel model which considers the interaction between the charges, such equations of state are derived for a plasma and the entropy is deduced. The technique to obtain the modified entropy production is based on usual developments but including the modified equations of state giving the regular result plus some extra terms. We derive an expression of the modified entropy production in terms of the tensorial Hermitian moments hr1…rm(m) by means of the irreducible tensorial Hermite polynomials.

10.
Chemistry ; 25(66): 15046-15049, 2019 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-31553088

RESUMEN

A universal, practical and scalable organocatalytic hydrocyanation manifold to provide ß-substituted acrylonitriles bearing an electron-withdrawing functionality has been implemented. The catalytic manifold operates under the reactivity generation principle "a good nucleophile generates a strong base", and it uses 1,4-diazabicyclo[2.2.2]octane (DABCO) as the catalyst, activated terminal alkynes as substrates and acetone cyanohydrin as the cyanide source. The acrylonitriles obtained as E,Z mixtures are straightforwardly resolved by simple flash chromatography delivering the pure isomers in preparative amounts.

11.
Molecules ; 24(16)2019 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-31405075

RESUMEN

In this review, we discuss the nature of the different physicochemical factors affecting the valence isomerism between 2H-pyrans (2HPs) and 1-oxatrienes, and we describe the most versatile synthetic methods reported in recent literature to access to 2HPs, with the only exception of 2HPs fused to aromatic rings (i.e., 2H-chromenes), which are not included in this review.


Asunto(s)
Piranos/química , Piranos/síntesis química , Catálisis , Estereoisomerismo
12.
Chemistry ; 23(42): 10048-10052, 2017 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-28621466

RESUMEN

An all-pericyclic manifold is developed for the construction of topologically diverse, structurally complex and natural product-like polycyclic chemotypes. The manifold uses readily accessible tertiary propargyl vinyl ethers as substrates and imidazole as a catalyst to form up to two new rings, three new C-C bonds, six stereogenic centers and one transannular oxo-bridge. The manifold is efficient, scalable and instrumentally simple to perform and entails a propargyl Claisen rearrangement-[1,3]H shift, an oxa-6π-electrocyclization, and an intramolecular Diels-Alder reaction.

13.
J Org Chem ; 82(10): 5328-5336, 2017 05 19.
Artículo en Inglés | MEDLINE | ID: mdl-28467064

RESUMEN

Herein we describe a salicylaldehyde-annulation reaction as a plug and play toolkit to diversify the complexity of naturally occurring ketones. The protocol entails the transformation of the polycyclic natural ketone into its propargyl vinyl ether derivative (two synthetic steps) and its microwave-assisted imidazole-catalyzed domino rearrangement to generate the salicylaldehyde ring. This annexed unit allows further synthetic transformations: e.g., the installation of a pharmacophore module to generate natural product-pharmacophore hybrids endowed with unknown biological (pharmaceutical) annotations.

14.
J Org Chem ; 81(20): 10099-10105, 2016 10 21.
Artículo en Inglés | MEDLINE | ID: mdl-27709940

RESUMEN

A microwave-assisted and base-catalyzed domino manifold to construct 2,4-cyclohexadienone derivatives has been implemented. The domino manifold uses easily accessible tertiary propargyl vinyl ethers bearing a methine group at the homopropargylic position and imidazole as the catalyst to deliver 2,4-cyclohexadienones featuring a key formyl group and a quaternized carbon atom in good yields.

15.
Rheumatol Int ; 35(2): 323-6, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25086629

RESUMEN

The aims of the study were to assess efficacy and safety of TNF-alpha antagonists (anti-TNF) in a cohort of patients with juvenile idiopathic arthritis (JIA) who began treatment under 4 years old and to assess relapse rate after methotrexate and/or anti-TNF withdrawal. We made a retrospective charts review of our non-systemic JIA patients treated with anti-TNF under 4 years of age between January 2006 and April 2013. Demographics, epidemiologic, clinical, laboratory data and rate of relapse after treatment withdrawal due to clinical remission were collected. Efficacy and safety end points included side effects (SE) and time to achieve clinical remission. We included 27 patients, 23 received etanercept and 4 adalimumab with a median age of 3.01 (range 0.88-3.97) years at anti-TNF beginning and 1.94 (range 0.18-5.44) and 2.39 (range 0.18-7.24) years of treatment and follow-up, respectively. All patients had previously received disease-modifying antirheumatic drugs at optimal dose. Nineteen patients reached clinical remission on treatment in a median time of 9.1 (range 6.23-21.17) months. Four of those relapsed during treatment. Six developed mild SE, mostly mild infections. No serious SE were described. Eleven patients who reached clinical remission relapsed after treatment withdrawal. None achieved clinical remission off treatment. Most patients reached clinical remission on anti-TNF. In our cohort of patients, etanercept and adalimumab were safe, with mostly mild infections and no serious SE. We observed a high relapse rate during treatment withdrawal.


Asunto(s)
Anticuerpos Monoclonales Humanizados/uso terapéutico , Antirreumáticos/uso terapéutico , Artritis Juvenil/tratamiento farmacológico , Inmunoglobulina G/uso terapéutico , Receptores del Factor de Necrosis Tumoral/uso terapéutico , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores , Adalimumab , Factores de Edad , Preescolar , Quimioterapia Combinada , Etanercept , Femenino , Humanos , Lactante , Masculino , Metotrexato/uso terapéutico , Recurrencia , Inducción de Remisión , Estudios Retrospectivos , Resultado del Tratamiento , Privación de Tratamiento
16.
JCO Oncol Pract ; : OP2400031, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38917401

RESUMEN

PURPOSE: Oral capecitabine improves convenience compared to intravenous therapies but presents monitoring challenges. We conducted a randomized pilot trial to evaluate a mobile health intervention to remotely monitor capecitabine adherence and patient-reported outcomes (PROs) among women with breast cancer. METHODS: Patients with breast cancer prescribed capecitabine, an oral chemotherapy with a complex, cyclical regimen, were randomly assigned to enhanced usual care (EUC) or PRO arm. Participants were asked to use a smart pill bottle to measure adherence (timing and dose) and complete baseline and 90-day follow-up surveys. PRO participants received text messages for missed or incorrect doses and weekly text-based symptom assessments, and their oncologists received alerts for severe symptoms or missed doses. We compared nonadherence (<80%) and changes from enrollment to follow-up on reported physical and mental health quality-of-life scores and number of severe symptoms by study arm. RESULTS: Overall, 32 women were randomly assigned (17 EUC and 15 PRO): 28 (87.5%) received the intervention and 24 (78.1%) completed the follow-up survey. Among participants who received the intervention, PRO participants responded to 83.3% of symptom questions; 7.7% of PRO participants were nonadherent compared with 40.0% of EUC participants (P = .049). Among those who completed the follow-up survey, 12.5% of PRO participants had reductions in their mental health composite scores compared with 69.2% of EUC participants (P = .011); 10% of PRO participants had more severe symptoms at follow-up compared with 57.1% of EUC participants (P = .019). CONCLUSION: A mobile health intervention using text message reminders and symptom assessments improved medication adherence and mental health quality-of-life scores and lowered symptom burden of patients with breast cancer prescribed capecitabine. Future work should evaluate the longer-term impacts of this intervention.

17.
Front Pharmacol ; 15: 1344042, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38500765

RESUMEN

This work explores the biological evaluation of novel cyanomethyl vinyl ether derivatives as antiproliferative agents. Tubulin, crucial to microtubule structure and function, is a target for cancer therapies. In vitro cytotoxicity assessments revealed significant activity in SKOV3 ovarian carcinoma cells and A549 lung carcinoma cells. Structure-Activity Relationship (SAR) analysis indicated that the E isomer and specific substitutions influenced the biological activity. Computational assays predicted favorable ADME properties, highlighting potential as anticancerous agents. Molecular docking studies demonstrated that compound 12E, with the E geometry of the double bond and fused polyaromatic rings such as phenanthrene, has robust interaction with tubulin, suggesting enhanced stability due to diverse amino acid interactions. Comparative spatial distributions with colchicine further indicated potential mechanistic similarities.

18.
J Clin Transl Sci ; 8(1): e71, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38690226

RESUMEN

Introduction: Addressing social determinants of health (SDOH) is fundamental to improving health outcomes. At a student-run free clinic, we developed a screening process to understand the SDOH needs and resource utilization of Milwaukee's uninsured population. Methods: In this cross-sectional study, we screened adult patients without health insurance (N = 238) for nine traditional SDOH needs as well as their access to dental and mental health care between October 2021 and October 2022. Patients were surveyed at intervals greater than or equal to 30 days. We assessed correlations between SDOH needs and trends in patient-reported resource usefulness. Results: Access to dental care (64.7%) and health insurance (51.3%) were the most frequently endorsed needs. We found significant correlations (P ≤ 0.05) between various SDOH needs. Notably, mental health access needs significantly correlated with dental (r = 0.41; 95% CI = 0.19, 0.63), medications (r = 0.51; 95% CI = 0.30, 0.72), utilities (r = 0.39; 95% CI = 0.17, 0.61), and food insecurity (r = 0.42; 95% CI = 0.19, 0.64). Food-housing (r = 0.55; 95% CI = 0.32, 0.78), housing-medications (r = 0.58; 95% CI = 0.35, 0.81), and medications-food (r = 0.53; 95% CI = 0.32, 0.74) were significantly correlated with each other. Longitudinal assessment of patient-reported usefulness informed changes in the resources offered. Conclusions: Understanding prominent SDOH needs can inform resource offerings and interventions, addressing root causes that burden under-resourced patients. In this study, patient-reported data about resource usefulness prompted the curation of new resources and volunteer roles. This proof-of-concept study shows how longitudinally tracking SDOH needs at low-resource clinics can inform psychosocial resources.

19.
Int J Parasitol Drugs Drug Resist ; 24: 100531, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38484645

RESUMEN

Leishmaniasis and Chagas disease are parasitic infections that affect millions of people worldwide, producing thousands of deaths per year. The current treatments against these pathologies are not totally effective and produce some side effects in the patients. Acrylonitrile derivatives are a group of compounds that have shown activity against these two diseases. In this work, four novels synthetic acrylonitriles were evaluated against the intracellular form and extracellular forms of L. amazonensis and T. cruzi. The compounds 2 and 3 demonstrate to have good selectivity indexes against both parasites, specifically the compound 3 against the amastigote form (SI = 6 against L. amazonensis and SI = 7.4 against T. cruzi). In addition, the parasites treated with these two compounds demonstrate to produce a programmed cell death, since they were positive for the events studied related to this type of death, including chromatin condensation, accumulation of reactive oxygen species and alteration of the mitochondrial membrane potential. In conclusion, this work confirms that acrylonitriles is a source of possible new compounds against kinetoplastids, however, more studies are needed to corroborate this activity.


Asunto(s)
Acrilonitrilo , Antiprotozoarios , Enfermedad de Chagas , Leishmania mexicana , Trypanosoma cruzi , Humanos , Antiprotozoarios/farmacología , Acrilonitrilo/farmacología , Acrilonitrilo/uso terapéutico , Enfermedad de Chagas/tratamiento farmacológico , Muerte Celular
20.
Chem Sci ; 14(45): 12953-12960, 2023 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-38023528

RESUMEN

The discovery of molecular organic cages (MOCs) is inhibited by the limited organic-chemical space of the building blocks designed to fulfill strict geometric requirements for efficient assembly. Using intramolecular attractive or repulsive non-covalent interactions to control the conformation of flexible systems can effectively augment the variety of building blocks, ultimately facilitating the exploration of new MOCs. In this study, we introduce a set of boronic acid tripods that were designed using rational design principles. Conformational control was induced by extending the tripod's arms by a 2,3-dimethylbenzene unit, leading to the efficient formation of a tetrapodal nanometer-sized boroxine cage. The new building block's versatility was demonstrated by performing cage metamorphosis upon adding an aromatic tetraol. This led to a quantitative boroxine-to-boronate transformation and a topological shift from tetrahedral to trigonal bipyramidal.

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