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1.
Pediatr Res ; 95(2): 573-578, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37985865

RESUMEN

BACKGROUND: Infants born less than 29 weeks, or extremely preterm (EPT), experience increased morbidity and mortality. We hypothesized that exposure to maternal infection might contribute to neurodevelopmental impairment (NDI) or death at 2 years of age. METHODS: We conducted a retrospective cohort study of EPT infants from January 2010 to December 2020. Maternal data extracted included maternal infections, classified as extrauterine or intrauterine. Placental pathologic and infant data were extracted. The primary outcome was NDI or death at 2 years of age. RESULTS: 548 EPT infants were born to 496 pregnant people: 379 (69%) were not exposed to any documented maternal infection prenatally, 124 (23%) to extrauterine infection, and 45 (8%) to intrauterine infection. Neither diagnosis of maternal extrauterine nor intrauterine infection was associated with NDI or death at 2 years of age (p > 0.05). Acute histologic chorioamnionitis was associated with NDI or death at 2 years of age (p = 0.033). CONCLUSIONS: Maternal infection was not associated with NDI or death at 2 years of age in EPT infants. However, acute histologic chorioamnionitis was associated with this outcome. Further work should investigate the differential influence of infection and immune response with this pathology as relates to outcomes in EPT infants. IMPACT: Maternal infection was not associated with neurodevelopmental impairment (NDI) or death at 2 years of age in extremely preterm (EPT) infants. This is reassuring support that mechanisms at the maternal-fetal interface largely protect the EPT infant. However, pathologic findings of acute histologic chorioamnionitis were associated with NDI and death at 2 years of age. Further work should investigate the differential influence of infection and immune response with acute histologic chorioamnionitis on pathology as relates to outcomes in EPT infants.


Asunto(s)
Corioamnionitis , Recien Nacido Extremadamente Prematuro , Lactante , Humanos , Recién Nacido , Femenino , Embarazo , Estudios Retrospectivos , Placenta , Edad Gestacional
2.
Proc Natl Acad Sci U S A ; 118(6)2021 02 09.
Artículo en Inglés | MEDLINE | ID: mdl-33526670

RESUMEN

KRAS interacts with the inner leaflet of the plasma membrane (PM) using a hybrid anchor that comprises a lysine-rich polybasic domain (PBD) and a C-terminal farnesyl chain. Electrostatic interactions have been envisaged as the primary determinant of interactions between KRAS and membranes. Here, we integrated molecular dynamics (MD) simulations and superresolution spatial analysis in mammalian cells and systematically compared four equally charged KRAS anchors: the wild-type farnesyl hexa-lysine and engineered mutants comprising farnesyl hexa-arginine, geranylgeranyl hexa-lysine, and geranylgeranyl hexa-arginine. MD simulations show that these equally charged KRAS mutant anchors exhibit distinct interactions and packing patterns with different phosphatidylserine (PtdSer) species, indicating that prenylated PBD-bilayer interactions extend beyond electrostatics. Similar observations were apparent in intact cells, where each anchor exhibited binding specificities for PtdSer species with distinct acyl chain compositions. Acyl chain composition determined responsiveness of the spatial organization of different PtdSer species to diverse PM perturbations, including transmembrane potential, cholesterol depletion, and PM curvature. In consequence, the spatial organization and PM binding of each KRAS anchor precisely reflected the behavior of its preferred PtdSer ligand to these same PM perturbations. Taken together these results show that small GTPase PBD-prenyl anchors, such as that of KRAS, have the capacity to encode binding specificity for specific acyl chains as well as lipid headgroups, which allow differential responses to biophysical perturbations that may have biological and signaling consequences for the anchored GTPase.


Asunto(s)
Fosfatidilserinas/química , Prenilación , Proteínas ras/química , Proteínas ras/metabolismo , Animales , Línea Celular , Colesterol/metabolismo , Humanos , Membrana Dobles de Lípidos/metabolismo , Proteínas Mutantes/metabolismo , Nanopartículas/química , Electricidad Estática
3.
Artículo en Inglés | MEDLINE | ID: mdl-38819187

RESUMEN

Background: Adenoid is a mass of lymphoid tissue seen in the posterior nasopharyngeal wall, generally seen in the pediatric age group, and it disappears as age advances till puberty. Patients with recurrent allergic rhinitis, otitis media, or persistent nasopharyngeal obstruction is associated with adenoid hypertrophy can be considered for adenoidectomy. Objective: To evaluate the potential role of Individualised Homeopathic medicine in managing allergic rhinitis and troublesome symptoms of upper respiratory tract in case of Enlarged adenoid. Method: An 8-year-old boy came with complaints of Allergic rhinitis, snoring, and recurrent upper respiratory tract infection. He had taken treatment for the same from modern medicine, but still, a recurrence of symptoms occurred. His radiological investigations showed grade II Adenoid Hypertrophy. The patient was advised surgical intervention, but their parents were unwilling to the same so the patient came for Homoeopathic Management. Individualized Homeopathic Medicine Calcarea carbonicum 200 C was prescribed to the patient. The patient's condition significantly improved during the course of his five years of treatment; his snoring has decreased, his allergic manifestations have diminished, and monthly check-ups have revealed that the patient's general and particular condition are improving. indicating the positive result of homeopathic medicine in the treatment of enlarged adenoid. Assessment of outcome is based on Radiological reports and modified Naranjo criteria. Result: Homoeopathic medicine Calcarea Carb 200 C is given to the patient based on the totality of symptoms. The incidence of allergic rhinitis has also declined following treatment. Furthermore, there has been a decrease in the grade of adenoid hypertrophy and a noticeable improvement in symptoms. Conclusion: This is a single case where evidence shows that complete patient recovery occurs with individualized Homoeopathic Medicine. this is single case study and more researches, observational studies and randomized control trials are required to ascertain homeopathy's efficacy in managing enlarged Adenoids.

4.
Alzheimers Dement ; 2024 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-39031528

RESUMEN

INTRODUCTION: The apolipoprotein E gene (APOE) is an established central player in the pathogenesis of Alzheimer's disease (AD), with distinct apoE isoforms exerting diverse effects. apoE influences not only amyloid-beta and tau pathologies but also lipid and energy metabolism, neuroinflammation, cerebral vascular health, and sex-dependent disease manifestations. Furthermore, ancestral background may significantly impact the link between APOE and AD, underscoring the need for more inclusive research. METHODS: In 2023, the Alzheimer's Association convened multidisciplinary researchers at the "AAIC Advancements: APOE" conference to discuss various topics, including apoE isoforms and their roles in AD pathogenesis, progress in apoE-targeted therapeutic strategies, updates on disease models and interventions that modulate apoE expression and function. RESULTS: This manuscript presents highlights from the conference and provides an overview of opportunities for further research in the field. DISCUSSION: Understanding apoE's multifaceted roles in AD pathogenesis will help develop targeted interventions for AD and advance the field of AD precision medicine. HIGHLIGHTS: APOE is a central player in the pathogenesis of Alzheimer's disease. APOE exerts a numerous effects throughout the brain on amyloid-beta, tau, and other pathways. The AAIC Advancements: APOE conference encouraged discussions and collaborations on understanding the role of APOE.

5.
J Environ Manage ; 365: 121644, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38963970

RESUMEN

The Earth's atmosphere contains ultrafine particles known as aerosols, which can be either liquid or solid particles suspended in gas. These aerosols originate from both natural sources and human activities, termed primary and secondary sources respectively. They have significant impacts on the environment, particularly when they transform into ultrafine particles or aerosol nanoparticles, due to their extremely fine atomic structure. With this context in mind, this review aims to elucidate the fundamentals of atmospheric-derived aerosol nanoparticles, covering their various sources, impacts, and methods for control and management. Natural sources such as marine, volcanic, dust, and bioaerosols are discussed, along with anthropogenic sources like the combustion of fossil fuels, biomass, and industrial waste. Aerosol nanoparticles can have several detrimental effects on ecosystems, prompting the exploration and analysis of eco-friendly, sustainable technologies for their removal or mitigation.Despite the adverse effects highlighted in the review, attention is also given to the generation of aerosol-derived atmospheric nanoparticles from biomass sources. This finding provides valuable scientific evidence and background for researchers in fields such as epidemiology, aerobiology, and toxicology, particularly concerning atmospheric nanoparticles.


Asunto(s)
Aerosoles , Atmósfera , Ecosistema , Nanopartículas , Aerosoles/análisis , Nanopartículas/química , Atmósfera/química , Contaminantes Atmosféricos/análisis , Humanos , Monitoreo del Ambiente , Material Particulado/análisis
6.
Clin Gerontol ; 47(1): 110-121, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-35998237

RESUMEN

OBJECTIVES: This program evaluation examined the feasibility, acceptability, and preliminary effects of an individualized coaching program to help older Veterans use VA mental health mobile apps to address mental health and well-being goals. METHODS: The program delivers individual technical and clinical support to facilitate the use of mobile devices and VA apps. Participants completed assessments of mobile device proficiency, app use frequency, app comfort, quality of life, and mental health symptoms (completed by a subset, n = 11) pre- and post-participation. RESULTS: Of 24 enrollees, 17 completed the program and received an average of 7.58 (SD = 2.87) sessions including the initial assessment. Mobile device proficiency (t (16) = -3.80, p = .002) and number of days/week apps were used (t (16) = -2.34, p = .032) increased significantly from pre- to post-participation. Depressive and anxiety scores decreased significantly (t (10) = 3.16, p = .010; t (10) = 3.29, p = .008) among the subset completing those measures. Overall satisfaction was high; 100% reported they would recommend the program. CONCLUSIONS: Findings suggest the program is feasible, highly acceptable, and increases mobile device proficiency and use of apps. CLINICAL IMPLICATIONS: Coaching programs can equip older adults with the skills to use mental health apps.


Asunto(s)
Tutoría , Aplicaciones Móviles , Telemedicina , Veteranos , Humanos , Anciano , Salud Mental , Estudios de Factibilidad , Calidad de Vida
7.
Breast Cancer Res ; 25(1): 31, 2023 03 22.
Artículo en Inglés | MEDLINE | ID: mdl-36949468

RESUMEN

BACKGROUND: Metastatic breast cancer is responsible for the death of the majority of breast cancer patients. In fact, metastatic BC is the 2nd leading cause of cancer-related deaths in women in the USA and worldwide. Triple negative breast cancer (TNBC), which lacks expression of hormone receptors (ER-α and PR) and ErbB2/HER2, is especially lethal due to its highly metastatic behavior, propensity to recur rapidly, and for its resistance to standard of care therapies, through mechanisms that remain incompletely understood. WAVE3 has been established as a promoter of TNBC development and metastatic progression. In this study, we investigated the molecular mechanisms whereby WAVE3 promotes therapy-resistance and cancer stemness in TNBC, through the regulation of ß-catenin stabilization. METHODS: The Cancer Genome Atlas dataset was used to assess the expression of WAVE3 and ß-catenin in breast cancer tumors. Kaplan-Meier Plotter analysis was used to correlate expression of WAVE3 and ß-catenin with breast cancer patients' survival probability. MTT assay was used to quantify cell survival. CRISPR/Cas9-mediated gene editing, 2D and 3D tumorsphere growth and invasion assays, Immunofluorescence, Western blotting, Semi-quantitative and real-time quantitative PCR analyses were applied to study the WAVE3/ß-catenin oncogenic signaling in TNBC. Tumor xenograft assays were used to study the role of WAVE3 in mediating chemotherapy resistance of TNBC tumors. RESULTS: Genetic inactivation of WAVE3 in combination of chemotherapy resulted in inhibition of 2D growth and 3D tumorsphere formation and invasion of TNBC cells in vitro, as well as tumor growth and metastasis in vivo. In addition, while re-expression of phospho-active WAVE3 in the WAVE3-deficient TNBC cells restored the oncogenic activity of WAVE3, re-expression of phospho-mutant WAVE3 did not. Further studies revealed that dual blocking of WAVE3 expression or phosphorylation in combination with chemotherapy treatment inhibited the activity and expression and stabilization of ß-catenin. Most importantly, the combination of WAVE3-deficiency or WAVE3-phospho-deficiency and chemotherapy suppressed the oncogenic behavior of chemoresistant TNBC cells, both in vitro and in vivo. CONCLUSION: We identified a novel WAVE3/ß-catenin oncogenic signaling axis that modulates chemoresistance of TNBC. This study suggests that a targeted therapeutic strategy against WAVE3 could be effective for the treatment of chemoresistant TNBC tumors.


Asunto(s)
Neoplasias de la Mama Triple Negativas , Femenino , Humanos , beta Catenina/genética , beta Catenina/metabolismo , beta Catenina/uso terapéutico , Línea Celular Tumoral , Proliferación Celular , Resistencia a Antineoplásicos/genética , Recurrencia Local de Neoplasia , Transducción de Señal , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Neoplasias de la Mama Triple Negativas/genética , Neoplasias de la Mama Triple Negativas/patología
8.
Small ; 19(50): e2304143, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37612811

RESUMEN

The rational design of noble metal-free electrocatalysts holds great promise for cost-effective green hydrogen generation through water electrolysis. In this context, here, the development of a superhydrophilic bifunctional electrocatalyst that facilitates both oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) in alkaline conditions is demonstrated. This is achieved through the in situ growth of hierarchical NiMoO4 @CoMoO4 ·xH2 O nanostructure on nickel foam (NF) via a two-step hydrothermal synthesis method. NiMoO4 @CoMoO4 ·xH2 O/NF facilitates OER and HER at the overpotentials of 180 and 220 mV, respectively, at the current density of 10 mA cm-2 . The NiMoO4 @CoMoO4 ·xH2 O/NF ǁ NiMoO4 @CoMoO4 ·xH2 O/NF cell can be operated at a potential of 1.60 V compared to 1.63 V displayed by the system based on the Pt/C@NFǁRuO2 @NF standard electrode pair configuration at 10 mA cm-2 for overall water splitting. The density functional theory calculations for the OER process elucidate that the lowest ΔG of NiMoO4 @CoMoO4 compared to both Ni and NiMoO4 is due to the presence of Co in the OER catalytic site and its synergistic interaction with NiMoO4 . The preparative strategy and mechanistic understanding make the windows open for the large-scale production of the robust and less expensive electrode material for the overall water electrolysis.

9.
Am J Geriatr Psychiatry ; 31(4): 279-290, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36754647

RESUMEN

OBJECTIVES: Cross-facility tele-geriatric psychiatry consultation is a promising model for providing specialty services to regions lacking sufficient geriatric psychiatry expertise. This evaluation focused on assessing the feasibility and acceptability of a consultation program developed by a geriatric psychiatrist in a Veterans Health Administration regional telehealth hub. DESIGN: Concurrent, mixed methods program evaluation. SETTING: A region served by a VA health care system telehealth hub. PARTICIPANTS: Patients with at least 1 geriatric mental health encounter with a geriatric psychiatrist consultant during a 1 year-period; referring providers. INTERVENTION: Virtual psychiatric evaluation of Veterans with time-limited follow-up and e-consultation with providers. MEASUREMENTS: Interviews with consultant, medical record data, and referring provider surveys. RESULTS: Three hundred fifteen Veterans (M = 76.0 ± 9.64 years; 40% rural-dwelling) had 666 encounters (M = 2.11 ± 1.78) with most occurring via clinical video telehealth (n = 443; 67.6%), e-consultation (n = 99; 15.1%), or video to home (n = 95; 14.5%). Most encounters were related to neurocognitive disorders, depressive disorders, trauma-related disorders, or serious mental illness. Referring providers (N = 58) highly recommended the program, reported high satisfaction, followed through with recommendations, and believed that this program increased access to geriatric psychiatry. CONCLUSIONS: This single program was shown to be feasible, acceptable, and valued by the referring providers. The findings highlighted the complex presentations of Veterans referred, and the current unmet need of providers of such Veterans, providing impetus for wider implementation.


Asunto(s)
Telemedicina , Veteranos , Humanos , Anciano , Cuidadores , Proyectos Piloto , Psiquiatría Geriátrica , Telemedicina/métodos , Derivación y Consulta
10.
Gerontol Geriatr Educ ; 44(3): 329-338, 2023 07 03.
Artículo en Inglés | MEDLINE | ID: mdl-35491904

RESUMEN

There is a growing need for psychologists with specialized training in geriatric mental health competencies. The Geriatric Scholars Program for Psychologists (GSP-P) was created to address this shortage within a large integrated healthcare system. In 2019, GSP-P piloted an advanced workshop designed to enhance expertise in geriatric mental health competencies among graduates of its foundational competencies core course. The workshop included 3.5 days of expert-led seminars regarding the biopsychosocial needs of older adults with chronic medical illness and was followed by completion of an individualized learning plan. This paper describes the evaluation of the course using a mixed methods with data collected prior to the workshop, immediately post-workshop, and six months post-workshop. Results indicated enthusiasm for the workshop, significant improvements in four geropsychology domains on the Pikes Peak Geropsychology Knowledge and Skill Assessment Tool, and benefit from completion of the independent learning plans. Our findings demonstrate that continued enhancement of geropsychology competencies through advanced coursework is feasible and improves knowledge and skill, particularly when combined with individualized learning plans.


Asunto(s)
Geriatría , Humanos , Anciano , Geriatría/educación , Psiquiatría Geriátrica/educación
11.
J Cell Sci ; 133(9)2020 05 11.
Artículo en Inglés | MEDLINE | ID: mdl-32393677

RESUMEN

Potassium loss and persistent shrinkage have both been implicated in apoptosis but their relationship and respective roles remain controversial. We approached this problem by clamping intracellular sodium and potassium in HeLa or MDCK cells using a combination of ionophores. Although ionophore treatment caused significant cell swelling, the initial volume could be restored and further reduced by application of sucrose. The swollen cells treated with ionophores remained viable for at least 8 h without any signs of apoptosis. Application of sucrose and the resulting shrinkage caused volume-dependent intrinsic apoptosis with all its classical features: inversion of phosphatidylserine, caspase activation and Bcl-2-dependent release of cytochrome c from mitochondria. In other experiments, apoptosis was induced by addition of the protein kinase inhibitor staurosporine at various degrees of swelling. Our results show that: (1) persistent shrinkage can cause apoptosis regardless of intracellular sodium or potassium composition or of the state of actin cytoskeleton; (2) strong potassium dependence of caspase activation is only observed in swollen cells with a reduced density of cytosolic proteins. We conclude that macromolecular crowding can be an important factor in determining the transition of cells to apoptosis.


Asunto(s)
Apoptosis , Inhibidores Enzimáticos , Caspasa 3 , Humanos , Mitocondrias , Potasio , Estaurosporina/farmacología
12.
FASEB J ; 35(5): e21533, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33826787

RESUMEN

Polycystic kidney disease (PKD) is a genetic disorder characterized by aberrant renal epithelial cell proliferation and formation and progressive growth of numerous fluid-filled cysts within the kidneys. Previously, we showed that there is elevated Notch signaling compared to normal renal epithelial cells and that Notch signaling contributes to the proliferation of cystic cells. Quinomycin A, a bis-intercalator peptide, has previously been shown to target the Notch signaling pathway and inhibit tumor growth in cancer. Here, we show that Quinomycin A decreased cell proliferation and cyst growth of human ADPKD cyst epithelial cells cultured within a 3D collagen gel. Treatment with Quinomycin A reduced kidney weight to body weight ratio and decreased renal cystic area and fibrosis in Pkd1RC/RC ; Pkd2+/- mice, an orthologous PKD mouse model. This was accompanied by reduced expression of Notch pathway proteins, RBPjk and HeyL and cell proliferation in kidneys of PKD mice. Quinomycin A treatments also normalized cilia length of cyst epithelial cells derived from the collecting ducts. This is the first study to demonstrate that Quinomycin A effectively inhibits PKD progression and suggests that Quinomycin A has potential therapeutic value for PKD patients.


Asunto(s)
Antibacterianos/farmacología , Quistes/tratamiento farmacológico , Modelos Animales de Enfermedad , Equinomicina/farmacología , Enfermedades Renales Poliquísticas/complicaciones , Canales Catiónicos TRPP/fisiología , Animales , Quistes/etiología , Quistes/metabolismo , Quistes/patología , Progresión de la Enfermedad , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados
13.
Prep Biochem Biotechnol ; 52(8): 924-936, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34895061

RESUMEN

Renewable natural gas (RNG) produced from anaerobic digestion (AD) of agricultural residues is emerging a serious biofuel alternative. Complex nature of lignocellulosic biomass residues coupled with complex biochemical transformations involving a large spectrum of microbial communities make anaerobic digestion of biomass difficult to understand and control. The present work aims at studying adaptation of microbial consortia in AD to substrates changes and correlating these to biogas generation. The double edged study deals with (a) using a common starting culture inoculum on different fractions of pretreated lignocellulosic biomass (LBM) fractions; and (b) using different starter inocula for gas generation from simple glucose substrate. Taxonomic analysis using 16S amplicon sequencing is shown to highlight changes in microbial community structure and predominance, majorly in hydrolytic bacterial populations. Observed variations in the rate of digestion with different starter inocula could be related to differences in microbial community structure and relative abundance. Results with different treated biomass fractions as substrates indicated that AD performance could be related to abundance of substrate-specific microbial communities. The work is a step to a deeper understanding of AD processes that may lead to better control and operation of AD for super-scale production of RNG from biomass feedstocks.


Asunto(s)
Biocombustibles , Consorcios Microbianos , Anaerobiosis , Biomasa , Hidrólisis
14.
Physiol Plant ; 173(4): 1448-1462, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33934375

RESUMEN

The plants endomembrane system of the cellular compartments with its complex membrane trafficking network facilitates transport of macromolecules. The endomembrane dynamics are essential for maintaining basic and specific cellular functions including adaptation to the extracellular environment. The plant vacuole serves as a reservoir for nutrients and toxic metabolites and performs detoxification processes to maintain cellular homeostasis. The overexpression of AlRab7, a vesicle trafficking gene from Aeluropus lagopoides, improved germination and growth and reduced ionic and oxidative stress in transgenics. Moreover, the root and shoot of transgenic tobacco showed differential accumulation of phytohormone ABA and IAA with different ionic stresses. The improved growth (root and shoot length) can be co-related with higher IAA accumulation with NaCl stress. The low Na+ /K+ ratio with different NaCl stress treatments indicates better ion homeostasis in transgenics. Furthermore, the increased stomatal density and higher number of open stomata on both leaf surfaces in transgenics during NaCl stress suggest better gaseous exchange/functioning of guard cells. The maintained or increased superoxide dismutase, catalase, ascorbate peroxidase, guaiacol peroxidase, and glutathione reductase antioxidative enzyme activities suggest that an extensive reactive oxygen species (ROS) scavenging system was triggered to detoxify cellular ROS, which remained at low levels in transgenics during the different stress treatments. Our results suggest that the AlRab7 transgenic tobacco ameliorates ionic stress by facilitating differential and selective ion transport at vacuolar membrane regulating hormone signaling, ROS homeostasis, stomatal development, and movement.


Asunto(s)
Nicotiana , Poaceae , Homeostasis , Hormonas , Plantas Modificadas Genéticamente , Especies Reactivas de Oxígeno , Estrés Fisiológico , Nicotiana/genética
15.
J Neurosci ; 39(27): 5336-5350, 2019 07 03.
Artículo en Inglés | MEDLINE | ID: mdl-31028117

RESUMEN

To make efficient foraging decisions, we must combine information about the values of available options with nonvalue information. Some accounts of ventromedial PFC (vmPFC) suggest that it has a narrow role limited to evaluating immediately available options. We examined responses of neurons in area 14 (a putative macaque homolog of human vmPFC) as 2 male macaques performed a novel foraging search task. Although many neurons encoded the values of immediately available offers, they also independently encoded several other variables that influence choice, but that are conceptually distinct from offer value. These variables include average reward rate, number of offers viewed per trial, previous offer values, previous outcome sizes, and the locations of the currently attended offer. We conclude that, rather than serving as specialized economic value center, vmPFC plays a broad role in integrating relevant environmental information to drive foraging decisions.SIGNIFICANCE STATEMENT Decision makers must often choose whether to take an immediately available option or continue to search for a better one. We hypothesized that this process, which is integral to foraging theory, leaves neural signatures in the brain region ventromedial PFC. Subjects performed a novel foraging task in which they searched through differently valued options and attempted to balance their reward threshold with various time costs. We found that neurons not only encode the values of immediately available offers, but multiplexed these with environmental variables, including reward rate, number of offers viewed, previous offer values, and spatial information. We conclude that vmPFC plays a rich role in encoding and integrating multiple foraging-related variables during economic decisions.


Asunto(s)
Toma de Decisiones/fisiología , Fijación Ocular , Neuronas/fisiología , Corteza Prefrontal/fisiología , Recompensa , Animales , Conducta Animal , Movimientos Oculares , Macaca mulatta , Masculino , Percepción Visual/fisiología
16.
Chemistry ; 26(35): 7900-7911, 2020 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-32363666

RESUMEN

Hydrogen production is vital for meeting future energy demands and managing environmental sustainability. Electrolysis of water is considered as the suitable method for H2 generation in a carbon-free pathway. Herein, the synthesis of highly efficient Co9 S8 -Ni3 S2 based hierarchical nanoflower arrays on nickel foam (NF) is explored through the one-pot hydrothermal method (Co9 S8 -Ni3 S2 /NF) for overall water splitting applications. The nanoflower arrays are self-supported on the NF without any binder, possessing the required porosity and structural characteristics. The obtained Co9 S8 -Ni3 S2 /NF displays high hydrogen evolution reaction (HER), as well as oxygen evolution reaction (OER), activities in 1 m KOH solution. The overpotentials exhibited by this system at 25 mA cm-2 are nearly 277 and 102 mV for HER and OER, respectively, in 1 m KOH solution. Subsequently, the overall water splitting was performed in 1 m KOH solution by employing Co9 S8 -Ni3 S2 /NF as both the anode and cathode, where the system required only 1.49, 1.60, and 1.69 V to deliver the current densities of 10, 25, and 50 mA cm-2 , respectively. Comparison of the activity of Co9 S8 -Ni3 S2 /NF with the state-of-the-art Pt/C and RuO2 coated on NF displays an enhanced performance for Co9 S8 -Ni3 S2 /NF both in the half-cell as well as in the full cell, emphasizing the significance of the present work. The post analysis of the material after water electrolysis confirms that the surface Co(OH)2 formed during the course of the reaction serves as the favorable active sites. Overall, the activity modulation achieved in the present case is attributed to the presence of the open-pore morphology of the as formed nanoflowers of Co9 S8 -Ni3 S2 on NF and the simultaneous presence of the surface Co(OH)2 along with the highly conducting Co9 S8 -Ni3 S2 core, which facilitates the adsorption of the reactants and subsequently its conversion into the gaseous products during water electrolysis.

17.
Parasitol Res ; 119(1): 165-175, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31807868

RESUMEN

A novel library of synthetic piperidine derivatives was used to screen against human lymphatic filarial parasite Brugia malayi. Piperidine has earlier been reported to have effect against parasites including rodent filarial nematodes. Compounds with hydroxyl substitutions (4Q and 4H) showed marked antifilarial effect. Molecular docking of 4H derivative showed more favorable thermodynamic parameters against thymidylate synthase of B. malayi than human counterpart. A wide difference between IC50 and LD50 ensured the therapeutic safety of the candidates against the filarial parasites. Addition of thymidine to the treatment regimen led to a significant reversal of antifilarial effect of 4H that confirmed inhibition of thymidylate synthase as pharmacological rationale. Apoptosis induced in the parasite as a consequence of probable inhibition of thymidylate synthase was studied by acridine orange/ethidium bromide fluorescent staining and poly (ADP-ribose) polymerase activity inhibition. Involvement of mitochondria was confirmed by decreased 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide (MTT) conversion and increased cytosolic cytochrome c level in 4H treated microfilariae, compared with the untreated microfilariae. Moreover, Michael adduct of chalcone targeting dihydrofolate reductase and piperidine targeting thymidylate synthase demonstrated synergistic effect on the parasite, indicating the importance of inhibition of DNA synthesis by combined effect. In conclusion, piperidine derivatives with hydroxyl substitution have a great therapeutic potential with an apoptotic rationale involving mitochondrial pathway, due to possible inhibition of parasitic thymidylate synthase.


Asunto(s)
Brugia Malayi/efectos de los fármacos , Filariasis Linfática/tratamiento farmacológico , Filaricidas/farmacología , Piperidinas/farmacología , Timidilato Sintasa/antagonistas & inhibidores , Animales , Chalcona/farmacología , Replicación del ADN/efectos de los fármacos , Filariasis Linfática/parasitología , Antagonistas del Ácido Fólico/farmacología , Humanos , Microfilarias/efectos de los fármacos , Simulación del Acoplamiento Molecular , Tetrahidrofolato Deshidrogenasa/efectos de los fármacos , Sales de Tetrazolio , Timidina/farmacología
18.
Anal Biochem ; 567: 8-13, 2019 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-30503709

RESUMEN

The response of fluorescent ion probes to ions is affected by intracellular environment. To properly calibrate them, intracellular and extracellular concentrations of the measured ion must be made equal. In the first, computational, part of this work, we show, using the example of potassium, that the two requirements for ion equilibration are complete dissipation of membrane potential and high membrane permeability for both potassium and sodium. In the second part, we tested the ability of various ionophores to achieve potassium equilibration in Jurkat and U937 cells and found a combination of valinomycin, nigericin, gramicidin and ouabain to be the most effective. In the third part, we applied this protocol to two potassium probes, APG-4 and APG-2. APG-4 shows good sensitivity to potassium but its fluorescence is sensitive to cell volume. Because ionophores cause cell swelling, calibration buffers had to be supplemented with 50 mM sucrose to keep cell volume constant. With these precautions taken, the average potassium concentrations in U937 and Jurkat cells were measured at 132 mM and 118 mM, respectively. The other tested probe, APG-2, is nonselective for cations; this is, however, a potentially useful property because the sum [K+] + [Na+] determines the amount of intracellular water.


Asunto(s)
Colorantes Fluorescentes/química , Calibración , Línea Celular Tumoral , Tamaño de la Célula/efectos de los fármacos , Citometría de Flujo/normas , Colorantes Fluorescentes/farmacología , Humanos , Modelos Teóricos , Valinomicina/farmacología
19.
Apoptosis ; 23(7-8): 449-455, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29978434

RESUMEN

Apoptotic volume decrease (AVD) is a characteristic cell shrinkage observed during apoptosis. There are at least two known processes that may result in the AVD: exit of intracellular water and splitting of cells into smaller fragments. Although AVD has traditionally been attributed to water loss, direct evidence for that is often lacking. In this study, we quantified intracellular water in staurosporine-treated cells using a previously described optical microscopic technique that combines volume measurements with quantitative phase analysis. Water loss was observed in detached HeLa and in adherent MDCK but not in adherent HeLa cells. At the same time, adherent HeLa and adherent MDCK cells exhibited visually similar apoptotic morphology, including fragmentation and activation of caspase-3. Morphological changes and caspase activation were prevented by chloride channel blockers DIDS and NPPB in both adherent and suspended HeLa cells, while potassium channel blocker TEA was ineffective. We conclude that staurosporine-induced dehydration is not a universal cell response but depends on the cell type and substrate attachment and can only be judged by direct water measurements. The effects of potassium or chloride channel blockers do not always correlate with the AVD.


Asunto(s)
Apoptosis/efectos de los fármacos , Estaurosporina/farmacología , Agua/metabolismo , Animales , Tamaño de la Célula/efectos de los fármacos , Perros , Inhibidores Enzimáticos/farmacología , Células HeLa , Humanos , Células de Riñón Canino Madin Darby , Potasio/metabolismo , Bloqueadores de los Canales de Potasio/farmacología
20.
Cytometry A ; 93(3): 297-304, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-28561905

RESUMEN

Intracellular protein concentration is an essential cell characteristic, which manifests itself through the refractive index. The latter can be measured from two or more mutually defocused brightfield images analyzed using the TIE (transport-of-intensity equation). In practice, however, TIE does not always achieve quantitatively accurate results on biological cells. Therefore, we have developed a calibration procedure that involves successive imaging of cells in solutions containing different amounts of added protein. This allows one to directly relate the output of TIE (T) to intracellular protein concentration C (g/L). The resultant relationship has a simple form: C ≈ 1.0(T/V), where V is the cell volume (µm3 ) and 1.0 is an empirical coefficient. We used calibrated TIE imaging to characterize the regulatory volume increase (RVI) in adherent HeLa cells placed in a hyperosmotic solution. We found that while no RVI occurs over the first 30-60 min, the protein concentration fully recovers after 20 h. Because interpretation of such long experiments may depend on whether protein concentration varies significantly throughout the cell cycle, we measured this parameter in three cell lines: HeLa, MDCK and DU145. Our data indicate that protein concentration remains relatively stable in these cells. © 2017 International Society for Advancement of Cytometry.


Asunto(s)
Procesamiento de Imagen Asistido por Computador/métodos , Proteínas/análisis , Animales , Línea Celular Tumoral , Tamaño de la Célula , Perros , Células HeLa , Humanos , Células de Riñón Canino Madin Darby , Concentración Osmolar
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