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2.
Front Immunol ; 14: 1230049, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37795086

RESUMEN

Iatrogenic vascular air embolism is a relatively infrequent event but is associated with significant morbidity and mortality. These emboli can arise in many clinical settings such as neurosurgery, cardiac surgery, and liver transplantation, but more recently, endoscopy, hemodialysis, thoracentesis, tissue biopsy, angiography, and central and peripheral venous access and removal have overtaken surgery and trauma as significant causes of vascular air embolism. The true incidence may be greater since many of these air emboli are asymptomatic and frequently go undiagnosed or unreported. Due to the rarity of vascular air embolism and because of the many manifestations, diagnoses can be difficult and require immediate therapeutic intervention. An iatrogenic air embolism can result in both venous and arterial emboli whose anatomic locations dictate the clinical course. Most clinically significant iatrogenic air emboli are caused by arterial obstruction of small vessels because the pulmonary gas exchange filters the more frequent, smaller volume bubbles that gain access to the venous circulation. However, there is a subset of patients with venous air emboli caused by larger volumes of air who present with more protean manifestations. There have been significant gains in the understanding of the interactions of fluid dynamics, hemostasis, and inflammation caused by air emboli due to in vitro and in vivo studies on flow dynamics of bubbles in small vessels. Intensive research regarding the thromboinflammatory changes at the level of the endothelium has been described recently. The obstruction of vessels by air emboli causes immediate pathoanatomic and immunologic and thromboinflammatory responses at the level of the endothelium. In this review, we describe those immunologic and thromboinflammatory responses at the level of the endothelium as well as evaluate traditional and novel forms of therapy for this rare and often unrecognized clinical condition.


Asunto(s)
Embolia Aérea , Trombosis , Humanos , Embolia Aérea/diagnóstico , Embolia Aérea/etiología , Embolia Aérea/terapia , Tromboinflamación , Inflamación/terapia , Inflamación/complicaciones , Trombosis/complicaciones , Enfermedad Iatrogénica
3.
Mol Plant Microbe Interact ; 36(12): 821-832, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37698455

RESUMEN

While arbuscular mycorrhizal (AM) fungi are known for providing host plants with improved drought tolerance, we know very little about the fungal response to drought in the context of the fungal-plant relationship. In this study, we evaluated the drought responses of the host and symbiont, using the fungus Rhizophagus irregularis with carrot (Daucus carota) as a plant model. Carrots inoculated with spores of R. irregularis DAOM 197198 were grown in a greenhouse. During taproot development, carrots were exposed to a 10-day water restriction. Compared with well-watered conditions, drought caused diminished photosynthetic activity and reduced plant growth in carrot with and without AM fungi. Droughted carrots had lower root colonization. For R. irregularis, 93% of 826 differentially expressed genes (DEGs) were upregulated during drought, including phosphate transporters, several predicted transport proteins of potassium, and the aquaporin RiAQPF2. In contrast, 78% of 2,486 DEGs in AM carrot were downregulated during drought, including the symbiosis-specific genes FatM, RAM2, and STR, which are implicated in lipid transfer from the host to the fungus and were upregulated exclusively in AM carrot during well-watered conditions. Overall, this study provides insight into the drought response of an AM fungus in relation to its host; the expression of genes related to symbiosis and nutrient exchange were downregulated in carrot but upregulated in the fungus. This study reveals that carrot and R. irregularis exhibit contrast in their regulation of gene expression during drought, with carrot reducing its apparent investment in symbiosis and the fungus increasing its apparent symbiotic efforts. [Formula: see text] Copyright © 2023 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.


Asunto(s)
Daucus carota , Micorrizas , Micorrizas/genética , Daucus carota/genética , Sequías , Simbiosis/genética , Perfilación de la Expresión Génica , Transcriptoma/genética , Agua/metabolismo , Raíces de Plantas/microbiología
4.
Nurs Open ; 10(8): 5682-5692, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37194656

RESUMEN

AIMS: To explore how students participating in Trio Upward Bound, a federally funded program for low-income and future first-time college students, experience bias when seeking healthcare. DESIGN: Qualitative group discussion. METHODS: Twenty-six Trio Upward Bound students participated in a group discussion about their experiences in healthcare. Questions for the discussion were developed using Critical Race Theory. Student comments were analysed and coded using Interpretive Phenomenological Analysis (IPA). Results were reported using Standards for Reporting Qualitative Research. RESULTS: Students reported experiencing bias in the healthcare setting because of age, race, native language, traditional dress and/or ability to advocate for their rights. Three themes emerged: communication, invisibility and healthcare rights. Through these themes students expressed how their experiences with healthcare lead to further cultural mistrust and mistrust of healthcare providers. The comments provided by students included examples of the five tenets of Critical Race Theory: the permanence of racism, colorblindness, interest convergence, Whiteness as property, and the critique of liberalism. Among this group of adolescents, early negative experiences in healthcare have led some to avoid seeking treatment. As this continues into adulthood it may further health disparities in these groups. Critical Race Theory is a valuable tool in understanding how race, class and age intersect to create disparities in healthcare.


Asunto(s)
Atención a la Salud , Disparidades en Atención de Salud , Racismo , Adolescente , Humanos , Investigación Cualitativa , Estudiantes , Estados Unidos
5.
Medicina (Kaunas) ; 57(7)2021 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-34202826

RESUMEN

Background and Objectives: Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) is a chronic condition distinguished by disabling fatigue associated with post-exertional malaise, as well as changes to sleep, autonomic functioning, and cognition. Mind-body interventions (MBIs) utilize the ongoing interaction between the mind and body to improve health and wellbeing. Purpose: To systematically review studies using MBIs for the treatment of ME/CFS symptoms. Materials and Methods: MEDLINE, EMBASE, CINAHL, PsycINFO, and Cochrane CENTRAL were searched (inception to September 2020). Interventional studies on adults diagnosed with ME/CFS, using one of the MBIs in comparison with any placebo, standard of care treatment or waitlist control, and measuring outcomes relevant to the signs and symptoms of ME/CFS and quality of life were assessed for inclusion. Characteristics and findings of the included studies were summarized using a descriptive approach. Results: 12 out of 382 retrieved references were included. Seven studies were randomized controlled trials (RCTs) with one including three reports (1 RCT, 2 single-arms); others were single-arm trials. Interventions included mindfulness-based stress reduction, mindfulness-based cognitive therapy, relaxation, Qigong, cognitive-behavioral stress management, acceptance and commitment therapy and isometric yoga. The outcomes measured most often were fatigue severity, anxiety/depression, and quality of life. Fatigue severity and symptoms of anxiety/depression were improved in nine and eight studies respectively, and three studies found that MBIs improved quality of life. Conclusions: Fatigue severity, anxiety/depression and physical and mental functioning were shown to be improved in patients receiving MBIs. However, small sample sizes, heterogeneous diagnostic criteria, and a high risk of bias may challenge this result. Further research using standardized outcomes would help advance the field.


Asunto(s)
Terapia Cognitivo-Conductual , Síndrome de Fatiga Crónica , Adulto , Depresión , Terapia por Ejercicio , Síndrome de Fatiga Crónica/terapia , Humanos , Calidad de Vida
6.
Int J STD AIDS ; 32(11): 1020-1027, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-33978529

RESUMEN

We assessed the prevalence of isoniazid preventive therapy (IPT) uptake and explored factors associated with IPT non-uptake among people living with HIV (PLHIV) using nationally representative data from the Zimbabwe Population-based HIV Impact Assessment (ZIMPHIA) 2015-2016. This was a cross-sectional study of 3418 PLHIV ZIMPHIA participants eligible for IPT, aged ≥15 years and in HIV care. Logistic regression modeling was performed to assess factors associated with self-reported IPT uptake. All analyses accounted for multistage survey design. IPT uptake among PLHIV was 12.7% (95% confidence interval (CI): 11.4-14.1). After adjusting for sex, age, rural/urban residence, TB screening at the last clinic visit, and hazardous alcohol use, rural residence was the strongest factor associated with IPT non-uptake (adjusted OR (aOR): 2.39, 95% CI: 1.82-3.12). Isoniazid preventive therapy non-uptake having significant associations with no TB screening at the last HIV care (aOR: 2.07, 95% CI: 1.54-2.78) and with hazardous alcohol use only in urban areas (aOR: 10.74, 95% CI: 3.60-32.0) might suggest suboptimal IPT eligibility screening regardless of residence, but more so in rural areas. Self-reported IPT use among PLHIV in Zimbabwe was low, 2 years after beginning national scale-up. This shows the importance of good TB screening procedures for successful IPT implementation.


Asunto(s)
Infecciones por VIH , Tuberculosis , Adulto , Antituberculosos/uso terapéutico , Estudios Transversales , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/epidemiología , Infecciones por VIH/prevención & control , Humanos , Isoniazida/uso terapéutico , Tuberculosis/tratamiento farmacológico , Tuberculosis/epidemiología , Tuberculosis/prevención & control , Zimbabwe/epidemiología
7.
Nat Commun ; 11(1): 3897, 2020 08 04.
Artículo en Inglés | MEDLINE | ID: mdl-32753587

RESUMEN

Lipo-chitooligosaccharides (LCOs) are signaling molecules produced by rhizobial bacteria that trigger the nodulation process in legumes, and by some fungi that also establish symbiotic relationships with plants, notably the arbuscular and ecto mycorrhizal fungi. Here, we show that many other fungi also produce LCOs. We tested 59 species representing most fungal phyla, and found that 53 species produce LCOs that can be detected by functional assays and/or by mass spectroscopy. LCO treatment affects spore germination, branching of hyphae, pseudohyphal growth, and transcription in non-symbiotic fungi from the Ascomycete and Basidiomycete phyla. Our findings suggest that LCO production is common among fungi, and LCOs may function as signals regulating fungal growth and development.


Asunto(s)
Quitina/análogos & derivados , Quitina/metabolismo , Hongos/crecimiento & desarrollo , Hongos/metabolismo , Transducción de Señal/fisiología , Ascomicetos/crecimiento & desarrollo , Basidiomycota/crecimiento & desarrollo , Quitosano , Ecología , Ácidos Grasos/metabolismo , Micorrizas/fisiología , Oligosacáridos , Rhizobium/metabolismo , Esporas Fúngicas/crecimiento & desarrollo , Simbiosis/fisiología
8.
J Pharmacol Exp Ther ; 374(2): 252-263, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32493725

RESUMEN

Deposition of hyperphosphorylated and aggregated tau protein in the central nervous system is characteristic of Alzheimer disease and other tauopathies. Tau is subject to O-linked N-acetylglucosamine (O-GlcNAc) modification, and O-GlcNAcylation of tau has been shown to influence tau phosphorylation and aggregation. Inhibition of O-GlcNAcase (OGA), the enzyme that removes O-GlcNAc moieties, is a novel strategy to attenuate the formation of pathologic tau. Here we described the in vitro and in vivo pharmacological properties of a novel and selective OGA inhibitor, MK-8719. In vitro, this compound is a potent inhibitor of the human OGA enzyme with comparable activity against the corresponding enzymes from mouse, rat, and dog. In vivo, oral administration of MK-8719 elevates brain and peripheral blood mononuclear cell O-GlcNAc levels in a dose-dependent manner. In addition, positron emission tomography imaging studies demonstrate robust target engagement of MK-8719 in the brains of rats and rTg4510 mice. In the rTg4510 mouse model of human tauopathy, MK-8719 significantly increases brain O-GlcNAc levels and reduces pathologic tau. The reduction in tau pathology in rTg4510 mice is accompanied by attenuation of brain atrophy, including reduction of forebrain volume loss as revealed by volumetric magnetic resonance imaging analysis. These findings suggest that OGA inhibition may reduce tau pathology in tauopathies. However, since hundreds of O-GlcNAcylated proteins may be influenced by OGA inhibition, it will be critical to understand the physiologic and toxicological consequences of chronic O-GlcNAc elevation in vivo. SIGNIFICANCE STATEMENT: MK-8719 is a novel, selective, and potent O-linked N-acetylglucosamine (O-GlcNAc)-ase (OGA) inhibitor that inhibits OGA enzyme activity across multiple species with comparable in vitro potency. In vivo, MK-8719 elevates brain O-GlcNAc levels, reduces pathological tau, and ameliorates brain atrophy in the rTg4510 mouse model of tauopathy. These findings indicate that OGA inhibition may be a promising therapeutic strategy for the treatment of Alzheimer disease and other tauopathies.


Asunto(s)
Inhibidores Enzimáticos/farmacología , Tauopatías/tratamiento farmacológico , Tauopatías/metabolismo , beta-N-Acetilhexosaminidasas/antagonistas & inhibidores , Proteínas tau/metabolismo , Animales , Atrofia/tratamiento farmacológico , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Encéfalo/patología , Modelos Animales de Enfermedad , Inhibidores Enzimáticos/uso terapéutico , Locomoción/efectos de los fármacos , Masculino , Ratones , Células PC12 , Ratas , Tauopatías/patología , Tauopatías/fisiopatología
9.
J Pharmacol Exp Ther ; 373(2): 311-324, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32094294

RESUMEN

Treatments for cognitive deficits associated with central nervous system (CNS) disorders such as Alzheimer disease and schizophrenia remain significant unmet medical needs that incur substantial pressure on the health care system. The α7 nicotinic acetylcholine receptor (nAChR) has garnered substantial attention as a target for cognitive deficits based on receptor localization, robust preclinical effects, genetics implicating its involvement in cognitive disorders, and encouraging, albeit mixed, clinical data with α7 nAChR orthosteric agonists. Importantly, previous orthosteric agonists at this receptor suffered from off-target activity, receptor desensitization, and an inverted U-shaped dose-effect curve in preclinical assays that limit their clinical utility. To overcome the challenges with orthosteric agonists, we have identified a novel selective α7 positive allosteric modulator (PAM), BNC375. This compound is selective over related receptors and potentiates acetylcholine-evoked α7 currents with only marginal effect on the receptor desensitization kinetics. In addition, BNC375 enhances long-term potentiation of electrically evoked synaptic responses in rat hippocampal slices and in vivo. Systemic administration of BNC375 reverses scopolamine-induced cognitive deficits in rat novel object recognition and rhesus monkey object retrieval detour (ORD) task over a wide range of exposures, showing no evidence of an inverted U-shaped dose-effect curve. The compound also improves performance in the ORD task in aged African green monkeys. Moreover, ex vivo 13C-NMR analysis indicates that BNC375 treatment can enhance neurotransmitter release in rat medial prefrontal cortex. These findings suggest that α7 nAChR PAMs have multiple advantages over orthosteric α7 nAChR agonists for the treatment of cognitive dysfunction associated with CNS diseases. SIGNIFICANCE STATEMENT: BNC375 is a novel and selective α7 nicotinic acetylcholine receptor (nAChR) positive allosteric modulator (PAM) that potentiates acetylcholine-evoked α7 currents in in vitro assays with little to no effect on the desensitization kinetics. In vivo, BNC375 demonstrated robust procognitive effects in multiple preclinical models across a wide exposure range. These results suggest that α7 nAChR PAMs have therapeutic potential in central nervous system diseases with cognitive impairments.


Asunto(s)
Bencetonio/farmacología , Clorobencenos/farmacología , Receptor Nicotínico de Acetilcolina alfa 7/agonistas , Regulación Alostérica , Animales , Encéfalo/efectos de los fármacos , Encéfalo/fisiología , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Cognición/efectos de los fármacos , Potenciación a Largo Plazo/efectos de los fármacos , Macaca mulatta , Masculino , Neurotransmisores/metabolismo , Ratas , Ratas Sprague-Dawley , Ratas Wistar , Escopolamina/farmacología
10.
J Med Chem ; 62(22): 10062-10097, 2019 11 27.
Artículo en Inglés | MEDLINE | ID: mdl-31487175

RESUMEN

Inhibition of O-GlcNAcase (OGA) has emerged as a promising therapeutic approach to treat tau pathology in neurodegenerative diseases such as Alzheimer's disease and progressive supranuclear palsy. Beginning with carbohydrate-based lead molecules, we pursued an optimization strategy of reducing polar surface area to align the desired drug-like properties of potency, selectivity, high central nervous system (CNS) exposure, metabolic stability, favorable pharmacokinetics, and robust in vivo pharmacodynamic response. Herein, we describe the medicinal chemistry and pharmacological studies that led to the identification of (3aR,5S,6S,7R,7aR)-5-(difluoromethyl)-2-(ethylamino)-3a,6,7,7a-tetrahydro-5H-pyrano[3,2-d]thiazole-6,7-diol 42 (MK-8719), a highly potent and selective OGA inhibitor with excellent CNS penetration that has been advanced to first-in-human phase I clinical trials.


Asunto(s)
Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacología , beta-N-Acetilhexosaminidasas/antagonistas & inhibidores , Administración Oral , Animales , Disponibilidad Biológica , Encéfalo/efectos de los fármacos , Perros , Descubrimiento de Drogas , Inhibidores Enzimáticos/sangre , Inhibidores Enzimáticos/farmacocinética , Humanos , Macaca mulatta , Masculino , Células PC12 , Ratas , Ratas Wistar , Relación Estructura-Actividad , Tauopatías/tratamiento farmacológico , beta-N-Acetilhexosaminidasas/química , beta-N-Acetilhexosaminidasas/metabolismo
11.
HERD ; 12(2): 116-129, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30309256

RESUMEN

OBJECTIVES: To examine the magnitude of impact of two nature-themed window murals on physiological processes, as measured by heart rate and blood pressure, of pediatric patients. BACKGROUND: Many children and adolescents find at least one aspect of the hospitalization process frightening or anxiety provoking. One physical feature linked to stress reduction is access to positive distractions. Views of nature are one of the most common forms of positive distractions in healthcare environments. Patient room windows are the most common way patients are exposed to natural elements. Exposure to views of nature is linked to a number of positive impacts on physiological outcomes. Unfortunately, not every patient room will be able to provide a nature-filled window view. In situations where nature scenes do not occur, enhanced nature views may be utilized to replicate many of the same benefits as actual nature views. METHODS: Pediatric patients were randomly assigned to one of the three room conditions: aquatic window mural, tree window mural, or control condition. The medical data of participants ( n = 90) who stayed in the rooms were gathered and evaluated for differences. RESULTS: Data analysis supports the notion that patient stress is heightened at the time of admission. Patients in the rooms with murals were found to have improvements in heart rate and systolic blood pressure in comparison to patients in control rooms, suggesting that the murals had an impact on physiological processes. Data also suggest that subject matter played a role, as patients in tree murals rooms had the most health-related outcomes.


Asunto(s)
Arteterapia/métodos , Naturaleza , Pinturas/psicología , Pinturas/estadística & datos numéricos , Habitaciones de Pacientes , Estrés Fisiológico/fisiología , Estrés Psicológico/terapia , Niño , Femenino , Humanos , Masculino , Estrés Psicológico/prevención & control
12.
J Neuroinflammation ; 15(1): 256, 2018 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-30189875

RESUMEN

BACKGROUND: Alzheimer's disease (AD) is a chronic neurodegenerative disease with pathological hallmarks including the formation of extracellular aggregates of amyloid-beta (Aß) known as plaques and intracellular tau tangles. Coincident with the formation of Aß plaques is recruitment and activation of glial cells to the plaque forming a plaque niche. In addition to histological data showing the formation of the niche, AD genetic studies have added to the growing appreciation of how dysfunctional glia pathways drive neuropathology, with emphasis on microglia pathways. Genomic approaches enable comparisons of human disease profiles between different mouse models informing on their utility to evaluate secondary changes to triggers such as Aß deposition. METHODS: In this study, we utilized two animal models of AD to examine and characterize the AD-associated pathology: the Tg2576 Swedish APP (KM670/671NL) and TgCRND8 Swedish plus Indiana APP (KM670/671NL + V717F) lines. We used laser capture microscopy (LCM) to isolate samples surrounding Thio-S positive plaques from distal non-plaque tissue. These samples were then analyzed using RNA sequencing. RESULTS: We determined age-associated transcriptomic differences between two similar yet distinct APP transgenic mouse models, known to differ in proportional amyloidogenic species and plaque deposition rates. In Tg2576, human AD gene signatures were not observed despite profiling mice out to 15 months of age. TgCRND8 mice however showed progressive and robust induction of lysomal, neuroimmune, and ITIM/ITAM-associated gene signatures overlapping with prior human AD brain transcriptomic studies. Notably, RNAseq analyses highlighted the vast majority of transcriptional changes observed in aging TgCRND8 cortical brain homogenates were in fact specifically enriched within the plaque niche samples. Data uncovered plaque-associated enrichment of microglia-related genes such as ITIM/ITAM-associated genes and pathway markers of phagocytosis. CONCLUSION: This work may help guide improved translational value of APP mouse models of AD, particularly for strategies aimed at targeting neuroimmune and neurodegenerative pathways, by demonstrating that TgCRND8 more closely recapitulates specific human AD-associated transcriptional responses.


Asunto(s)
Enfermedad de Alzheimer , Péptidos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Corteza Cerebral/metabolismo , Citocinas/metabolismo , Regulación de la Expresión Génica/genética , Factores de Edad , Enfermedad de Alzheimer/genética , Enfermedad de Alzheimer/inmunología , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/patología , Péptidos beta-Amiloides/genética , Animales , Proteínas de Unión al Calcio/metabolismo , Corteza Cerebral/patología , Correlación de Datos , Modelos Animales de Enfermedad , Humanos , Captura por Microdisección con Láser , Ratones , Ratones Transgénicos , Proteínas de Microfilamentos/metabolismo , Mutación/genética , Placa Amiloide/patología , ARN Mensajero/metabolismo , Transcriptoma
13.
PLoS One ; 13(4): e0195486, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29624602

RESUMEN

Although tau pathology, behavioral deficits, and neuronal loss are observed in patients with tauopathies, the relationship between these endpoints has not been clearly established. Here we found that rTg4510 mice, which overexpress human mutant tau in the forebrain, develop progressive age-dependent increases in locomotor activity (LMA), which correlates with neurofibrillary tangle (NFT) pathology, hyperphosphorylated tau levels, and brain atrophy. To further clarify the relationship between these endpoints, we treated the rTg4510 mice with either doxycycline to reduce mutant tau expression or an O-GlcNAcase inhibitor Thiamet G, which has been shown to ameliorate tau pathology in animal models. We found that both doxycycline and Thiamet G treatments starting at 2 months of age prevented the progression of hyperactivity, slowed brain atrophy, and reduced brain hyperphosphorylated tau. In contrast, initiating doxycycline treatment at 4 months reduced neither brain hyperphosphorylated tau nor hyperactivity, further confirming the relationship between these measures. Collectively, our results demonstrate a unique behavioral phenotype in the rTg4510 mouse model of tauopathy that strongly correlates with disease progression, and that early interventions which reduce tau pathology ameliorate the progression of the locomotor dysfunction. These findings suggest that better understanding the relationship between locomotor deficits and tau pathology in the rTg4510 model may improve our understanding of the mechanisms underlying behavioral disturbances in patients with tauopathies.


Asunto(s)
Tauopatías/tratamiento farmacológico , Proteínas tau/metabolismo , Animales , Encéfalo/metabolismo , Encéfalo/patología , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Doxiciclina/uso terapéutico , Inhibidores Enzimáticos/uso terapéutico , Expresión Génica/efectos de los fármacos , Humanos , Ratones , Ratones de la Cepa 129 , Ratones Transgénicos , Actividad Motora/genética , Actividad Motora/fisiología , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , Ovillos Neurofibrilares/patología , Fosforilación , Piranos/uso terapéutico , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Tauopatías/patología , Tauopatías/fisiopatología , Tiazoles/uso terapéutico , beta-N-Acetilhexosaminidasas/antagonistas & inhibidores , Proteínas tau/genética
14.
New Phytol ; 213(2): 531-536, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27780291

RESUMEN

531 I. 531 II. 532 III. 532 IV. 534 V. 534 535 References 535 SUMMARY: Arbuscular mycorrhizal (AM) fungi associate with the vast majority of land plants, providing mutual nutritional benefits and protecting hosts against biotic and abiotic stresses. Significant progress was made recently in our understanding of the genomic organization, the obligate requirements, and the sexual nature of these fungi through the release and subsequent mining of genome sequences. Genomic and genetic approaches also improved our understanding of the signal repertoire used by AM fungi and their plant hosts to recognize each other for the initiation and maintenance of this association. Evolutionary and bioinformatic analyses of host and nonhost plant genomes represent novel ways with which to decipher host mechanisms controlling these associations and shed light on the stepwise acquisition of this genetic toolkit during plant evolution. Mining fungal and plant genomes along with evolutionary and genetic approaches will improve understanding of these symbiotic associations and, in the long term, their usefulness in agricultural settings.


Asunto(s)
Evolución Biológica , Genómica , Micorrizas/genética , Hongos/genética , Simbiosis/genética
15.
Psychopharmacology (Berl) ; 225(1): 21-30, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22825578

RESUMEN

RATIONALE: The current standards of care for Alzheimer's disease, acetylcholinesterase inhibitors, have limited efficacy due to a host of mechanism-related side effects arising from indiscriminate activation of muscarinic and nicotinic receptors. The M1 muscarinic receptor is predominantly expressed in the brain in regions involved in cognition, and therefore selective activation of the M1 receptor would be expected to boost cognitive performance with reduced risk of peripheral side effects. OBJECTIVES: Here we investigated whether the selective M1 muscarinic receptor positive allosteric modulator, PQCA, improves cognitive performance and cerebral blood flow. RESULTS: PQCA attenuated a scopolamine-induced deficit in novel object recognition in rat, self-ordered spatial search in cynomolgus macaque, and the object retrieval detour task in rhesus macaque. Beneficial effects in each of these assays and species were observed at similar plasma drug concentrations. Furthermore, at similar drug concentrations that were effective in the behavioral studies, PQCA increased blood flow in the frontal cortex of mice, providing a translational biomarker that could be used to guide dose selection for clinical studies. CONCLUSIONS: These findings provide a framework for appropriately testing an M1 selective compound in patients with Alzheimer's disease.


Asunto(s)
Encéfalo/efectos de los fármacos , Cognición/efectos de los fármacos , Piperidinas/farmacología , Quinolizinas/farmacología , Receptor Muscarínico M1/efectos de los fármacos , Regulación Alostérica , Enfermedad de Alzheimer/tratamiento farmacológico , Enfermedad de Alzheimer/fisiopatología , Animales , Encéfalo/irrigación sanguínea , Trastornos del Conocimiento/tratamiento farmacológico , Trastornos del Conocimiento/etiología , Trastornos del Conocimiento/fisiopatología , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Femenino , Macaca fascicularis , Macaca mulatta , Masculino , Ratones , Piperidinas/administración & dosificación , Quinolizinas/administración & dosificación , Ratas , Ratas Wistar , Receptor Muscarínico M1/metabolismo , Flujo Sanguíneo Regional/efectos de los fármacos , Escopolamina/toxicidad , Especificidad de la Especie
16.
Proc Natl Acad Sci U S A ; 106(37): 15950-5, 2009 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-19717450

RESUMEN

The forebrain cholinergic system promotes higher brain function in part by signaling through the M(1) muscarinic acetylcholine receptor (mAChR). During Alzheimer's disease (AD), these cholinergic neurons degenerate, therefore selectively activating M(1) receptors could improve cognitive function in these patients while avoiding unwanted peripheral responses associated with non-selective muscarinic agonists. We describe here benzyl quinolone carboxylic acid (BQCA), a highly selective allosteric potentiator of the M(1) mAChR. BQCA reduces the concentration of ACh required to activate M(1) up to 129-fold with an inflection point value of 845 nM. No potentiation, agonism, or antagonism activity on other mAChRs is observed up to 100 microM. Furthermore studies in M(1)(-/-) mice demonstrates that BQCA requires M(1) to promote inositol phosphate turnover in primary neurons and to increase c-fos and arc RNA expression and ERK phosphorylation in the brain. Radioligand-binding assays, molecular modeling, and site-directed mutagenesis experiments indicate that BQCA acts at an allosteric site involving residues Y179 and W400. BQCA reverses scopolamine-induced memory deficits in contextual fear conditioning, increases blood flow to the cerebral cortex, and increases wakefulness while reducing delta sleep. In contrast to M(1) allosteric agonists, which do not improve memory in scopolamine-challenged mice in contextual fear conditioning, BQCA induces beta-arrestin recruitment to M(1), suggesting a role for this signal transduction mechanism in the cholinergic modulation of memory. In summary, BQCA exploits an allosteric potentiation mechanism to provide selectivity for the M(1) receptor and represents a promising therapeutic strategy for cognitive disorders.


Asunto(s)
Receptor Muscarínico M1/metabolismo , Regulación Alostérica , Secuencia de Aminoácidos , Animales , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Células CHO , Señalización del Calcio/efectos de los fármacos , Circulación Cerebrovascular/efectos de los fármacos , Circulación Cerebrovascular/fisiología , Condicionamiento Psicológico/efectos de los fármacos , Condicionamiento Psicológico/fisiología , Cricetinae , Cricetulus , Perros , Miedo/efectos de los fármacos , Miedo/fisiología , Humanos , Técnicas In Vitro , Fosfatos de Inositol/metabolismo , Macaca mulatta , Ratones , Ratones Noqueados , Modelos Moleculares , Estructura Terciaria de Proteína , Quinolonas/farmacología , Ensayo de Unión Radioligante , Ratas , Receptor Muscarínico M1/química , Receptor Muscarínico M1/deficiencia , Receptor Muscarínico M1/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Sueño/efectos de los fármacos , Sueño/fisiología
17.
Exp Neurol ; 205(1): 166-76, 2007 May.
Artículo en Inglés | MEDLINE | ID: mdl-17368447

RESUMEN

A history of depression is a risk factor for Alzheimer's disease (AD), suggesting the possibility that antidepressants administered prophylactically might retard the disease process and preserve cognitive function. Here we report that pre-symptomatic treatment with the antidepressant paroxetine attenuates the disease process and improves cognitive performance in the 3xTgAD mouse model of AD. Five-month-old male and female 3xTgAD and non-transgenic mice were administered either paroxetine or saline daily for 5 months. Open-field activity was tested in 7-month-old mice and performance in passive avoidance and Morris swim tasks were evaluated at 10 months. 3xTgAD mice exhibited reduced exploratory activity, increased transfer latency in the passive avoidance test and impaired performance in the Morris spatial navigation task compared to nontransgenic control mice. Paroxetine treatment ameliorated the spatial navigation deficit in 3xTgAD male and female mice, without affecting swim speed or distance traveled, suggesting a preservation of cognitive function. Levels of amyloid beta-peptide (Abeta) and numbers of Abeta immunoreactive neurons were significantly reduced in the hippocampus of male and female paroxetine-treated 3xTgAD mice compared to saline-treated 3xTgAD mice. Female 3xTgAD mice exhibited significantly less tau pathology in the hippocampus and amygdala compared to male 3xTgAD mice, and paroxetine lessened tau pathology in male 3xTgAD mice. The ability of a safe and effective antidepressant to suppress neuropathological changes and improve cognitive performance in a mouse model suggests that such drugs administered prophylactically might retard the development of AD in humans.


Asunto(s)
Enfermedad de Alzheimer/prevención & control , Enfermedad de Alzheimer/psicología , Conducta Animal/efectos de los fármacos , Trastornos Mentales/psicología , Paroxetina/farmacología , Inhibidores Selectivos de la Recaptación de Serotonina/farmacología , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/patología , Amígdala del Cerebelo/metabolismo , Amígdala del Cerebelo/patología , Péptidos beta-Amiloides/metabolismo , Animales , Reacción de Prevención/efectos de los fármacos , Corteza Cerebral/metabolismo , Modelos Animales de Enfermedad , Femenino , Hipocampo/metabolismo , Hipocampo/patología , Masculino , Aprendizaje por Laberinto/efectos de los fármacos , Ratones , Ratones Transgénicos , Actividad Motora/efectos de los fármacos , Fragmentos de Péptidos/metabolismo , Natación , Tauopatías/prevención & control
18.
Free Radic Biol Med ; 42(5): 665-74, 2007 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-17291990

RESUMEN

Asthma is an increasingly common disorder responsible for considerable morbidity and mortality. Although obesity is a risk factor for asthma and weight loss can improve symptoms, many patients do not adhere to low calorie diets and the impact of dietary restriction on the disease process is unknown. A study was designed to determine if overweight asthma patients would adhere to an alternate day calorie restriction (ADCR) dietary regimen, and to establish the effects of the diet on their symptoms, pulmonary function and markers of oxidative stress, and inflammation. Ten subjects with BMI>30 were maintained for 8 weeks on a dietary regimen in which they ate ad libitum every other day, while consuming less than 20% of their normal calorie intake on the intervening days. At baseline, and at designated time points during the 8-week study, asthma control, symptoms, and Quality of Life questionnaires (ACQ, ASUI, mini-AQLQ) were assessed and blood was collected for analyses of markers of general health, oxidative stress, and inflammation. Peak expiratory flow (PEF) was measured daily on awakening. Pre- and postbronchodilator spirometry was obtained at baseline and 8 weeks. Nine of the subjects adhered to the diet and lost an average of 8% of their initial weight during the study. Their asthma-related symptoms, control, and QOL improved significantly, and PEF increased significantly, within 2 weeks of diet initiation; these changes persisted for the duration of the study. Spirometry was unaffected by ADCR. Levels of serum beta-hydroxybutyrate were increased and levels of leptin were decreased on CR days, indicating a shift in energy metabolism toward utilization of fatty acids and confirming compliance with the diet. The improved clinical findings were associated with decreased levels of serum cholesterol and triglycerides, striking reductions in markers of oxidative stress (8-isoprostane, nitrotyrosine, protein carbonyls, and 4-hydroxynonenal adducts), and increased levels of the antioxidant uric acid. Indicators of inflammation, including serum tumor necrosis factor-alpha and brain-derived neurotrophic factor, were also significantly decreased by ADCR. Compliance with the ADCR diet was high, symptoms and pulmonary function improved, and oxidative stress and inflammation declined in response to the dietary intervention. These findings demonstrate rapid and sustained beneficial effects of ADCR on the underlying disease process in subjects with asthma, suggesting a novel approach for therapeutic intervention in this disorder.


Asunto(s)
Asma/dietoterapia , Asma/metabolismo , Restricción Calórica/métodos , Mediadores de Inflamación/metabolismo , Sobrepeso , Estrés Oxidativo , Adulto , Asma/complicaciones , Asma/fisiopatología , Biomarcadores/metabolismo , Metabolismo Energético , Humanos , Metabolismo de los Lípidos , Pulmón/fisiopatología
19.
Neurobiol Dis ; 26(1): 212-20, 2007 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17306982

RESUMEN

Alzheimer's disease (AD) is a neurodegenerative disorder characterized by progressive decline in cognitive function associated with the neuropathological hallmarks amyloid beta-peptide (Abeta) plaques and neurofibrillary tangles. Because aging is the major risk factor for AD, and dietary energy restriction can retard aging processes in the brain, we tested the hypothesis that two different energy restriction regimens, 40% calorie restriction (CR) and intermittent fasting (IF) can protect against cognitive decline in the triple-transgenic mouse model of AD (3xTgAD mice). Groups of 3xTgAD mice were maintained on an ad libitum control diet, or CR or IF diets, beginning at 3 months of age. Half of the mice in each diet group were subjected to behavioral testing (Morris swim task and open field apparatus) at 10 months of age and the other half at 17 months of age. At 10 months 3xTgAD mice on the control diet exhibited reduced exploratory activity compared to non-transgenic mice and to 3xTgAD mice on CR and IF diets. Overall, there were no major differences in performance in the water maze among genotypes or diets in 10-month-old mice. In 17-month-old 3xTgAD mice the CR and IF groups exhibited higher levels of exploratory behavior, and performed better in both the goal latency and probe trials of the swim task, compared to 3xTgAD mice on the control diet. 3xTgAD mice in the CR group showed lower levels of Abeta1-40, Abeta1-42 and phospho-tau in the hippocampus compared to the control diet group, whereas Abeta and phospho-tau levels were not decreased in 3xTgAD mice in the IF group. IF may therefore protect neurons against adverse effects of Abeta and tau pathologies on synaptic function. We conclude that CR and IF dietary regimens can ameliorate age-related deficits in cognitive function by mechanisms that may or may not be related to Abeta and tau pathologies.


Asunto(s)
Envejecimiento/psicología , Enfermedad de Alzheimer/dietoterapia , Enfermedad de Alzheimer/psicología , Restricción Calórica/psicología , Ayuno/psicología , Péptidos beta-Amiloides/metabolismo , Animales , Femenino , Humanos , Immunoblotting , Masculino , Aprendizaje por Laberinto/fisiología , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Actividad Motora/fisiología , Proteínas tau/metabolismo
20.
J Pharmacol Exp Ther ; 318(3): 1083-93, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16728593

RESUMEN

Voltage-gated Na(+) channels may play important roles in establishing pathological neuronal hyperexcitability associated with chronic pain in humans. Na(+) channel blockers, such as carbamazepine (CBZ) and lamotrigine (LTG), are efficacious in treating neuropathic pain; however, their therapeutic utility is compromised by central nervous system side effects. We reasoned that it may be possible to gain superior control over pain states and, in particular, a better therapeutic index, by designing broad-spectrum Na(+) channel blockers with higher potency, faster onset kinetics, and greater levels of state dependence than existing drugs. 2-[4-(4-Chloro-2-fluorophenoxy)phenyl]-pyrimidine-4-carboxamide (PPPA) is a novel structural analog of the state-dependent Na(+) channel blocker V102862 [4-(4-fluorophenoxy)benzaldehyde semicarbazone]. Tested on recombinant rat Na(v)1.2 channels and native Na(+) currents in cultured rat dorsal root ganglion neurons, PPPA was approximately 1000 times more potent, had 2000-fold faster binding kinetics, and > or =10-fold higher levels of state dependence than CBZ and LTG. Tested in rat pain models against mechanical endpoints, PPPA had minimal effective doses of 1 to 3 mg/kg p.o. in partial sciatic nerve ligation, Freund's complete adjuvant, and postincisional pain. In all cases, efficacy was similar to clinically relevant comparators. Importantly, PPPA did not produce motor deficits in the accelerating Rotarod assay of ataxia at doses up to 30 mg/kg p.o., indicating a therapeutic index >10, which was superior to CBZ and LTG. Our experiments suggest that high-potency, broad-spectrum, state-dependent Na(+) channel blockers will have clinical utility for treating neuropathic, inflammatory, and postsurgical pain. Optimizing the biophysical parameters of broad-spectrum voltage-gated Na(+) channel blockers may lead to improved pain therapeutics.


Asunto(s)
Dolor/tratamiento farmacológico , Pirimidinas/farmacología , Bloqueadores de los Canales de Sodio/farmacología , Animales , Carbamazepina/farmacología , Humanos , Hiperalgesia/tratamiento farmacológico , Lamotrigina , Masculino , Actividad Motora/efectos de los fármacos , Ratas , Ratas Sprague-Dawley , Semicarbazonas/farmacología , Tetrodotoxina/farmacología , Triazinas/farmacología
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