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1.
Ophthalmic Plast Reconstr Surg ; 40(3): 245-253, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38133607

RESUMEN

PURPOSE: To describe a unique case of a fatal self-enucleation and review previously published cases. METHODS: The authors describe a unique case of a complete unilateral self-enucleation while under the influence of drugs, which resulted in severe intracranial hemorrhages, right internal carotid artery opacification, and death. A literature review was performed by searching articles published before January 2023 in the Pubmed/MEDLINE database using the keywords "auto-enucleation or self-enucleation." Cases of self-inflicted damage to the globe without severing any connections were excluded. RESULTS: A literature review identified a total of 54 articles and 75 patients who had self-enucleated at least one globe completely (84.0%). Their average age was 37 years and 50.7% were male. At the time of auto-enucleation, 64.0% of these patients had known psychiatric disorders, and 28.0% were found to be under the influence of illicit drugs or alcohol. Auto-enucleation resulted in intracranial complications in 26.7% of cases. There has been 1 prior case, which, like the authors' case, resulted in death due to intracranial complications. However, this occurred in a patient who partially enucleated one eye after a self-inflicted injury to the fellow eye. The current case is unique as these complications resulted from a complete unilateral auto-enucleation. CONCLUSIONS: The severity of this case's presentation and outcome highlights the importance of prompt neuroimaging and a thorough assessment. Prompt psychiatric assessment and treatment are also required.


Asunto(s)
Enucleación del Ojo , Adulto , Humanos , Masculino , Resultado Fatal , Tomografía Computarizada por Rayos X , Femenino
2.
J Craniofac Surg ; 33(8): 2443-2446, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35968973

RESUMEN

OBJECTIVE: Facial recognition software (FRS) is becoming pervasive in society for commercial use, security systems, and entertainment. Alteration of the facial appearance with surgery poses a challenge to these algorithms, but several methods are being studied to overcome this issue. This study systematically reviews methods used in facial recognition of surgically altered faces. MATERIALS AND METHODS: A systematic review was performed by searching PubMed and Institute of Electrical and Electronics Engineers (IEEE) databases to identify studies addressing FRS and surgery. On initial review, 178 manuscripts were identified relating to FRS and surgery and allowed division into multiple subgroups. The decision was made to focus on the recognition of surgically altered faces. RESULTS: Eligible studies included those reports in English on FRS of surgically altered faces, and 39 papers were included. Surgical procedures range from affecting skin surface, such as skin peeling, to altering facial features, such as rhinoplasty, mentoplasty, malar augmentation, brow lift, facelift, orthognathic surgery, facial reanimation, and facial feminization. Methods were classified into appearance-based, feature-based, and texture-based. Descriptive versus experimental protocols were characterized by different reporting outcomes and controls. Accuracy ranged from 19.1% to 85.35% using various analysis methods. CONCLUSIONS: Knowledge of available limitations and advantages can aid in counseling patients regarding personal technology use, security, and quell fears about surgery to evade authorities. Surgical knowledge can be utilized to improve FRS algorithms for postsurgical recognition.


Asunto(s)
Reconocimiento Facial , Procedimientos de Cirugía Plástica , Ritidoplastia , Masculino , Humanos , Procedimientos de Cirugía Plástica/métodos , Feminización , Ritidoplastia/métodos , Programas Informáticos
3.
Obesity (Silver Spring) ; 30(8): 1573-1578, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35894076

RESUMEN

OBJECTIVE: Using data from 2017, the authors have previously examined the coverage of obesity-related services in state employee health plans since 2009 and found improvements in coverage for obesity-related treatments. This study repeated the collection of similar data for 2021 and explored whether coverage had continued to increase or decline. METHODS: Data on obesity benefits for state employees were obtained from publicly available documents from relevant state websites. Source documents were reviewed for language that would indicate the availability of coverage for nutritional counseling, pharmacotherapy, and bariatric surgery. Use data were collected when available, but availability was limited. RESULTS: Coverage for some treatments of obesity continued to trend upward, as was the case between 2009 and 2017, but coverage for pharmacotherapy declined from 2017 to 2021. Use data were received from only eight states; analysis of these data indicated underuse of obesity benefits by plan enrollees compared with each state's rate of obesity. CONCLUSIONS: Despite promising new therapies, states in 2021 were less likely to provide coverage for antiobesity medications. Additionally, limited use data suggested that few eligible individuals may be receiving these services. In conclusion, state employee health plans are currently inadequate given the prevalence, severity, and costs of obesity.


Asunto(s)
Cirugía Bariátrica , Planes de Asistencia Médica para Empleados , Salud Laboral , Atención a la Salud , Humanos , Cobertura del Seguro , Obesidad/epidemiología , Obesidad/prevención & control , Estados Unidos/epidemiología
4.
Am J Rhinol Allergy ; 35(6): 902-909, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33622038

RESUMEN

BACKGROUND OBJECTIVE STUDY DESIGN: RARS is a challenging clinical problem that impacts many patients. This article seeks to systematically review the literature on RARS management. METHODS: Cochrane, PubMed, EMBASE, and other databases were queried for articles related to RARS dating from 1990 to present, according to PRISMA guidelines. Inclusion criteria included articles specifically addressing RARS management; studies with 3 or more patients; and articles in English. RESULTS: A total of 1022 titles/abstracts potentially related to RARS were identified. Of these, sixty-nine full texts were selected for review, and 10 met inclusion criteria (five with level 4 evidence, four with level 3 evidence, one with level 2 evidence). The studies included a total of 890 patients (Age range 5.8 to 53.5 years), with follow up ranging from 1 to 19 months. Endpoints were primarily based on symptomatic improvement, although some articles also reported post-treatment endoscopic and radiographic findings. Management options included medical therapy (intranasal steroids, antibiotics, nasal saline irrigations, N-acetylcysteine, allergy treatment, and decongestants), balloon sinus dilation (BSD), and endoscopic sinus surgery (ESS). Surgical patients (BSD and ESS) had a trend towards greater symptom control than medically-treated patients, but meta-analysis was not possible. CONCLUSION: Despite increasing interest in the treatment of RARS, there remains a lack of consensus regarding optimal management. The literature thus far, largely based on expert opinion, suggests that surgical management, either through balloon sinus dilation or endoscopic sinus surgery, may be helpful in improving symptoms and quality of life in those who do not respond to initial trials of medical management.


Asunto(s)
Senos Paranasales , Rinitis , Sinusitis , Enfermedad Aguda , Preescolar , Humanos , Lactante , Calidad de Vida , Rinitis/terapia , Sinusitis/terapia
5.
Am J Rhinol Allergy ; 35(3): 383-390, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-32954839

RESUMEN

BACKGROUND: RARS is a challenging clinical phenomenon that affects many patients, and diagnostic criteria for this condition are not fully characterized in the literature. OBJECTIVE: To examine diagnostic criteria for recurrent acute rhinosinusitis (RARS). STUDY DESIGN: Systematic review. METHODS: Cochrane, PubMed (MEDLINE), clinicaltrials.gov, EMBASE, Google Scholar, and Web of Science databases were queried for articles related to RARS dating from 1990 to present, according to PRISMA statement guidelines. Full text articles pertinent to the diagnostic criteria of RARS were included in this review. Inclusion criteria included articles specifically addressing RARS; studies with 3 or more patients; and articles in English. RESULTS: A total of 1022 titles/abstracts potentially related to RARS were identified. Of these, sixty-nine full texts were selected for review, and 22 of these ultimately met inclusion criteria. The level of evidence was generally low. Studies and guidelines have used many different definitions for RARS diagnosis over the years based on symptomatology, physical examination, nasal endoscopy, imaging, and laboratory domains. Clinically important RARS has been defined most commonly as 4 or more discrete episodes of ARS per year, but this frequency is typically based on expert opinion. Additionally, radiologic anatomic associations such as concha bullosa, accessory maxillary os, and narrowed infundibular distance may be associated with RARS. Endoscopic visualization and imaging are sometimes used to confirm the presence of sinus disease during exacerbations of RARS, but there is variability in this practice. CONCLUSION: The diagnostic definition for RARS has developed over time and is currently based on low level 4 and 5 evidence. Because of the migratory definition of RARS, comparing inter-study results of RARS management remains difficult, and future studies should aim to follow current expert guidelines on diagnostic criteria of RARS.


Asunto(s)
Rinitis , Sinusitis , Enfermedad Aguda , Humanos , Recurrencia , Estudios Retrospectivos , Rinitis/diagnóstico , Sinusitis/diagnóstico
6.
ChemMedChem ; 15(18): 1691-1698, 2020 09 16.
Artículo en Inglés | MEDLINE | ID: mdl-32583936

RESUMEN

Protein-protein interactions (PPIs), many of which are dominated by α-helical recognition domains, play key roles in many essential cellular processes, and the dysregulation of these interactions can cause detrimental effects. For instance, aberrant PPIs involving the Bcl-2 protein family can lead to several diseases including cancer, neurodegenerative diseases, and diabetes. Interactions between Bcl-2 pro-life proteins, such as Mcl-1, and pro-death proteins, such as Bim, regulate the intrinsic pathway of apoptosis. p53, a tumor-suppressor protein, also has a pivotal role in apoptosis and is negatively regulated by its E3 ubiquitin ligase HDM2. Both Mcl-1 and HDM2 are upregulated in numerous cancers, and, interestingly, there is crosstalk between both protein pathways. Recently, synergy has been observed between Mcl-1 and HDM2 inhibitors. Towards the development of new anticancer drugs, we herein describe a polypharmacology approach for the dual inhibition of Mcl-1 and HDM2 by employing three densely functionalized isoxazoles, pyrazoles, and thiazoles as mimetics of key α-helical domains of their partner proteins.


Asunto(s)
Antineoplásicos/farmacología , Diseño de Fármacos , Proteína 1 de la Secuencia de Leucemia de Células Mieloides/antagonistas & inhibidores , Neoplasias/tratamiento farmacológico , Proteínas Proto-Oncogénicas c-mdm2/antagonistas & inhibidores , Antineoplásicos/química , Relación Dosis-Respuesta a Droga , Humanos , Isoxazoles/química , Isoxazoles/farmacología , Estructura Molecular , Proteína 1 de la Secuencia de Leucemia de Células Mieloides/química , Proteína 1 de la Secuencia de Leucemia de Células Mieloides/metabolismo , Neoplasias/metabolismo , Unión Proteica/efectos de los fármacos , Conformación Proteica en Hélice alfa/efectos de los fármacos , Proteínas Proto-Oncogénicas c-mdm2/química , Proteínas Proto-Oncogénicas c-mdm2/metabolismo , Pirazoles/química , Pirazoles/farmacología , Relación Estructura-Actividad , Tiazoles/química , Tiazoles/farmacología
8.
Ann Clin Transl Neurol ; 5(12): 1622-1626, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30564628

RESUMEN

Aspartylglucosaminuria is a lysosomal storage disorder enriched in Finland. We report on a pair of non-Finnish siblings with aspartylglucosaminuria with autofluorescent inclusion bodies on optical coherence tomography, a finding not previously reported in this disorder. We performed a record review, neurological and neuropsychological evaluation, brain MRI, and optical coherence tomography for each patient. They are compound heterozygous for a 34-kb deletion and a c.365C>A novel variant of the AGA gene. Autofluorescent inclusion bodies were found on optical coherence tomography in the older, more severely affected brother. We hypothesize the finding represents a noninvasive biomarker of disease severity for aspartylglucosaminuria.

9.
Inflammopharmacology ; 26(5): 1219-1232, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29616452

RESUMEN

Rheumatoid arthritis (RA) is an autoimmune disease characterized by chronic inflammation of synovial tissues in joints, leading to progressive destruction of cartilage and joints. The disease-modifying anti-rheumatic drugs currently in use have side-effects. Thus, there is an urgent need for safe anti-inflammatory therapies for RA. This study aimed to evaluate the therapeutic effect of the flavonoid quercetin on arthritis in mice immunized with type II collagen (CII). An arthritis model was established in C57/BL6 mice by intradermal administration of chicken CII mixed with Freund's complete adjuvant. Quercetin (30 mg/kg orally) and methotrexate (0.75 mg intraperitoneally twice a week) were administered to investigate their protective effects against collagen-induced arthritis (CIA). Levels of tumour necrosis factor-alpha (TNF-α), interleukin-1 beta (IL-1ß), IL-6, and the matrix metalloproteinases (MMP), 3, and 9 were detected to assess the anti-inflammatory effect of quercetin. The mRNA expression of MMP3, MMP9, CCL2, and TNF-α was also measured by quantitative real-time PCR. Quercetin significantly alleviated joint inflammation by reducing the levels of circulating cytokines and MMPs. There was a significant decrease in the expression of TNFα and MMP genes in the ankle joints of arthritic mice. A significant reduction in the levels of knee-joint inflammatory mediators were observed with combined quercetin and methotrexate treatment. Thus, quercetin has the potential to prevent joint inflammation and could be used as an adjunct therapy for RA patients who have an inadequate response to anti-rheumatic monotherapy.


Asunto(s)
Artritis Experimental/tratamiento farmacológico , Artritis Reumatoide/tratamiento farmacológico , Mediadores de Inflamación/antagonistas & inhibidores , Inhibidores de la Metaloproteinasa de la Matriz/administración & dosificación , Metotrexato/administración & dosificación , Quercetina/administración & dosificación , Animales , Articulación del Tobillo/efectos de los fármacos , Artritis Experimental/sangre , Artritis Reumatoide/sangre , Proteína C-Reactiva/análisis , Quimioterapia Combinada , Femenino , Articulación de la Rodilla/efectos de los fármacos , Masculino , Ratones
10.
Bioorg Med Chem Lett ; 28(3): 523-528, 2018 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-29329659

RESUMEN

Inspired by a rhodanine-based dual inhibitor of Bcl-xL and Mcl-1, a focused library of analogues was prepared wherein the rhodanine core was replaced with a less promiscuous thiazolidine-2,4-dione scaffold. Compounds were initially evaluated for their abilities to inhibit Mcl-1. The most potent compound 12b inhibited Mcl-1 with a Ki of 155 nM. Further investigation revealed comparable inhibition of Bcl-xL (Ki = 90 nM), indicating that the dual inhibitory profile of the initial rhodanine lead had been retained upon switching the heterocycle core.


Asunto(s)
Descubrimiento de Drogas , Proteína 1 de la Secuencia de Leucemia de Células Mieloides/antagonistas & inhibidores , Tiazolidinedionas/farmacología , Relación Dosis-Respuesta a Droga , Humanos , Estructura Molecular , Proteína 1 de la Secuencia de Leucemia de Células Mieloides/metabolismo , Relación Estructura-Actividad , Tiazolidinedionas/síntesis química , Tiazolidinedionas/química
11.
J Autoimmun ; 86: 104-115, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-28964723

RESUMEN

Myelin oligodendrocyte glycoprotein (MOG) is exposed on the outer surface of the myelin sheath, and as such, represents a possible target antigen for antibodies in multiple sclerosis (MS) and other demyelinating diseases. However, despite extensive analyses, whether MOG-specific antibodies contribute to pathogenesis in human MS remains an area of uncertainty. In the current study we demonstrate that antibodies derived from adult MS patients exacerbate experimental autoimmune encephalomyelitis (EAE) in 'humanized' mice that transgenically express human FcγRs (hFcγRs). Importantly, this exacerbation is dependent on MOG recognition by the human-derived antibodies. The use of mice that express hFcγRs has allowed us to also investigate the contribution of these receptors to disease in the absence of confounding effects of cross-species differences. Specifically, by engineering the Fc region of MOG-specific antibodies to modulate FcγR and complement (C1q) binding, we reveal that FcγRs but not complement activation contribute to EAE pathogenesis. Importantly, selective enhancement of the affinities of these antibodies for specific FcγRs reveals that FcγRIIA is more important than FcγRIIIA in mediating disease exacerbation. These studies not only provide definitive evidence for the contribution of MOG-specific antibodies to MS, but also reveal mechanistic insight that could lead to new therapeutic targets.


Asunto(s)
Encefalomielitis Autoinmune Experimental/inmunología , Esclerosis Múltiple/inmunología , Glicoproteína Mielina-Oligodendrócito/inmunología , Animales , Autoanticuerpos/metabolismo , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Humanos , Ratones , Ratones SCID , Ratones Transgénicos , Vaina de Mielina/inmunología , Receptores de IgG/genética , Receptores de IgG/metabolismo
12.
Crit Rev Food Sci Nutr ; 57(17): 3601-3613, 2017 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-27874281

RESUMEN

Rheumatoid arthritis (RA) is an autoimmune condition that mainly affects peripheral joints. Although immunosuppressive drugs and non-steroidal anti-inflammatory drugs (NSAIDs) are used to treat this condition, these drugs have severe side effects. Flavonoids are the most abundant phenolic compounds which exhibit anti-oxidant, anti-inflammatory and immunomodulatory properties. Many bioactive flavonoids have powerful anti-inflammatory effects. However, a very few have reached clinical use. Dietary flavonoids have been reported to control joint inflammation and alleviate arthritis symptoms in both human RA and animal models of arthritis. There is little scientific evidence about their mechanism of actions in RA. We review the therapeutic effects of different groups of flavonoids belonging to the most common and abundant groups on RA. In particular, the probable mechanisms of major flavonoids on cells and chemical messengers involved in the inflammatory signaling components of RA are discussed in detail.


Asunto(s)
Antiinflamatorios no Esteroideos/uso terapéutico , Artritis Reumatoide/tratamiento farmacológico , Flavonoides/uso terapéutico , Humanos
13.
JAMA Neurol ; 71(11): 1421-8, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25264704

RESUMEN

IMPORTANCE: This study describes what is, to our knowledge, the previously unknown effect of glatiramer acetate therapy on B cells in patients with relapsing-remitting multiple sclerosis (MS). OBJECTIVE: To determine whether glatiramer acetate therapy normalizes dysregulated B-cell proliferation and cytokine production in patients with MS. DESIGN, SETTING, AND PARTICIPANTS: Twenty-two patients with MS who were receiving glatiramer acetate therapy and 22 treatment-naive patients with MS were recruited at The University of Texas Southwestern Medical Center MS clinic. Cell samples from healthy donors were obtained from HemaCare (Van Nuys, California) or Carter Blood Bank (Dallas, Texas). Treatment-naive patients with MS had not received any disease-modifying therapies for at least 3 months before the study. EXPOSURES: Glatiramer acetate therapy for at least 3 months at the time of the study. MAIN OUTCOMES AND MEASURES: B-cell phenotype and proliferation and immunoglobulin and cytokine secretion. RESULTS: A restoration of interleukin 10 production by peripheral B cells was observed in patients undergoing glatiramer acetate therapy as well as a significant reduction of interleukin 6 production in a subset of patients who received therapy for less than 32 months. Furthermore, proliferation in response to high-dose CD40L was altered and immunoglobulin production was elevated in in vitro-activated B cells obtained from patients who received glatiramer acetate. CONCLUSIONS AND RELEVANCE: Glatiramer acetate therapy remodels the composition of the B-cell compartment and influences cytokine secretion and immunoglobulin production. These data suggest that glatiramer acetate therapy affects several aspects of dysregulated B-cell function in MS that may contribute to the therapeutic mechanisms of glatiramer acetate.


Asunto(s)
Linfocitos B/efectos de los fármacos , Inmunosupresores/uso terapéutico , Esclerosis Múltiple Recurrente-Remitente/tratamiento farmacológico , Péptidos/uso terapéutico , Adulto , Citocinas/efectos de los fármacos , Femenino , Acetato de Glatiramer , Humanos , Masculino , Persona de Mediana Edad , Resultado del Tratamiento , Adulto Joven
14.
Surg Neurol Int ; 4: 62, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23772332

RESUMEN

BACKGROUND: With growing interest in global health, surgeons have created outreach missions to improve health care disparities in less developed countries. These efforts are mainly episodic with visiting surgeons performing the operations and minimal investment in local surgeon education. To create real and durable advancement in surgical services in disciplines that require urgent patient care, such as pediatric neurosurgery, improving the surgical armamentarium of the local surgeons must be the priority. METHODS: We propose a strategic design for extending surgical education missions throughout the Western Hemisphere in order to transfer modern surgical skills to local neurosurgeons. A selection criteria and structure for targeted missions is a derivative of logistical and pedagogical lessons ascertained from previous missions by our teams in Peru and Ukraine. RESULTS: Outreach programs should be applied to hospitals in capital cities to serve as a central referral center for maximal impact with fiscal efficiency. The host country should fulfill several criteria, including demonstration of geopolitical stability in combination with lack of modern neurosurgical care and equipment. The mission strategy is outlined as three to four 1-week visits with an initial site evaluation to establish a relationship with the hospital administration and host surgeons. Each visit should be characterized by collaboration between visiting and host surgeons on increasingly complex cases, with progressive transfer of skills over time. CONCLUSION: A strategic approach for surgical outreach missions should be built on collaboration and camaraderie between visiting and local neurosurgeons, with the mutual objective of cost-effective targeted renovation of their surgical equipment and skill repertoire.

15.
J Med Ethics ; 39(1): 51-4, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23001919

RESUMEN

Within the context of global health development approaches, surgical missions to provide care for underserved populations remain the least studied interventions with regard to their methodology. Because of the unique logistical needs of delivering operative care, surgical missions are often described solely in terms of cases performed, with a paucity of discourse on medical ethics. Within surgery, subspecialties that serve patients on a non-elective basis should, it could be argued, create mission strategies that involve a didactic approach and the propagation of sustainable surgical care. The ethical considerations have yet to be described for paediatric neurosurgical outreach missions. We present here the perspectives of neurosurgeons who have participated in surgical outreach missions in Central America, South America, Eastern Europe and sub-Saharan Africa from the vantage point of both the visiting mission team and the host team that accommodates the mission efforts.


Asunto(s)
Países Desarrollados , Países en Desarrollo , Misiones Médicas/ética , Neurocirugia/ética , Pediatría/ética , Adolescente , África del Sur del Sahara , América Central , Niño , Preescolar , Conflicto de Intereses , Europa Oriental , Recursos en Salud/ética , Recursos en Salud/estadística & datos numéricos , Humanos , Consentimiento Informado , Internet , Procedimientos Neuroquirúrgicos/ética , América del Sur , Equipo Quirúrgico
16.
Addict Biol ; 17(5): 908-19, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22017465

RESUMEN

Ghrelin (GHR) is an orexigenic gut peptide that interacts with brain ghrelin receptors (GHR-Rs) to promote food intake. Recent research suggests that GHR acts as a modulator of motivated behavior, suggesting a direct influence of GHR on brain reinforcement circuits. In the present studies, we investigated the role of GHR and GHR-Rs in brain reinforcement function. Pharmacological magnetic resonance imaging was used to spatially resolve the functional activation produced by systemic administration of an orexigenic GHR dose. The imaging data revealed a focal activation of a network of subcortical structures that comprise brain reinforcement circuits-ventral tegmental area, lateral hypothalamus and nucleus accumbens. We next analyzed whether brain reinforcement circuits require functional GHR-Rs. To this purpose, wild-type (WT) or mutant rats sustaining N-ethyl-N-nitrosourea-induced knockout of GHR-Rs (GHR-R null rats) were implanted with stimulating electrodes aimed at the lateral hypothalamus, shaped to respond for intracranial self-stimulation (ICSS) and then tested using a rate-frequency procedure to examine ICSS response patterns. WT rats were readily shaped using stimulation intensities of 75 µA, whereas GHR-R null rats required 300 µA for ICSS shaping. No differences in rate-frequency curves were noted for WT rats at 75 µA and GHR-R null rats at 300 µA. When current intensity was lowered to 100 µA, GHR-R null rats did not respond for ICSS. Taken collectively, these data suggest that systemic GHR can activate mesolimbic dopaminergic areas, and highlight a facilitative role of GHR-Rs on the activity of brain reinforcement systems.


Asunto(s)
Estimulantes del Apetito/farmacología , Encéfalo/efectos de los fármacos , Ghrelina/farmacología , Receptores de Ghrelina/fisiología , Refuerzo en Psicología , Animales , Circulación Cerebrovascular/efectos de los fármacos , Ingestión de Alimentos , Hormona del Crecimiento/metabolismo , Imagen por Resonancia Magnética , Masculino , Ratas , Ratas Endogámicas , Ratas Sprague-Dawley , Autoestimulación
17.
Addict Biol ; 17(6): 956-63, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21790898

RESUMEN

Systemic infusions of the orexigenic peptide ghrelin (GHR) increase dopamine levels within the nucleus accumbens and augment cocaine-stimulated locomotion and conditioned place preference in rats; observations that suggest an important role for GHR and GHR receptors (GHR-Rs) in drug reinforcement. In the present studies, we examined the development of cocaine locomotor sensitization in rats, sustaining either pharmacologic antagonism or genetic ablation of GHR-Rs. In a pharmacologic study, adult male rats were injected (i.p.) with either 0, 3 or 6 mg/kg JMV 2959 (a GHR-R1 receptor antagonist), and 20 minutes later, with either vehicle or 10 mg/kg cocaine HCl on each of 7 consecutive days. Rats pretreated with JMV 2959 showed significantly attenuated cocaine-induced hyperlocomotion. In a second study, adult wild-type (WT) or mutant rats sustaining ENU-induced knockout of GHR-R [GHR-R ((-/-) )] received daily injections (i.p.) of vehicle (0.9% saline) or 10.0 mg/kg cocaine HCl for 14 successive days. GHR-R null rats treated repeatedly with cocaine showed diminished development of cocaine locomotor sensitization relative to WT rats treated with cocaine. To verify the lack of GHR-R function in the GHR-R ((-/-) ) rats, a separate feeding experiment was conducted in which WT rats, but not GHR-R ((-/-) ) rats, were noted to eat more after a systemic injection of 15 nmol GHR than after vehicle. These results suggest that GHR-R activity is required for the induction of locomotor sensitization to cocaine and complement an emerging literature implicating central GHR systems in drug reward. GHR is an orexigenic gut peptide that is transported across the blood-brain barrier and interacts with GHR-Rs located on ventral tegmental dopamine neurons.


Asunto(s)
Cocaína/farmacología , Inhibidores de Captación de Dopamina/farmacología , Locomoción/efectos de los fármacos , Actividad Motora/efectos de los fármacos , Receptores de Ghrelina , Animales , Conducta Animal/efectos de los fármacos , Técnicas de Inactivación de Genes , Glicina/análogos & derivados , Glicina/farmacología , Masculino , Ratas , Ratas Sprague-Dawley , Receptores de Ghrelina/antagonistas & inhibidores , Receptores de Ghrelina/genética , Receptores de Ghrelina/fisiología , Triazoles/farmacología
18.
J Exp Biol ; 214(Pt 19): 3238-47, 2011 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-21900471

RESUMEN

The ability to control the bandwidth, amplitude and duration of echolocation pulses is a crucial aspect of echolocation performance but few details are known about the neural mechanisms underlying the control of these voice parameters in any mammal. The basal ganglia (BG) are a suite of forebrain nuclei centrally involved in sensory-motor control and are characterized by their dependence on dopamine. We hypothesized that pharmacological manipulation of brain dopamine levels could reveal how BG circuits might influence the acoustic structure of bat echolocation pulses. A single intraperitoneal injection of a low dose (5 mg kg(-1)) of the neurotoxin 1-methyl-4-phenylpyridine (MPTP), which selectively targets dopamine-producing cells of the substantia nigra, produced a rapid degradation in pulse acoustic structure and eliminated the bat's ability to make compensatory changes in pulse amplitude in response to background noise, i.e. the Lombard response. However, high-performance liquid chromatography (HPLC) measurements of striatal dopamine concentrations revealed that the main effect of MPTP was a fourfold increase rather than the predicted decrease in striatal dopamine levels. After first using autoradiographic methods to confirm the presence and location of D(1)- and D(2)-type dopamine receptors in the bat striatum, systemic injections of receptor subtype-specific agonists showed that MPTP's effects on pulse acoustics were mimicked by a D(2)-type dopamine receptor agonist (Quinpirole) but not by a D(1)-type dopamine receptor agonist (SKF82958). The results suggest that BG circuits have the capacity to influence echolocation pulse acoustics, particularly via D(2)-type dopamine receptor-mediated pathways, and may therefore represent an important mechanism for vocal control in bats.


Asunto(s)
Quirópteros/fisiología , Cuerpo Estriado/efectos de los fármacos , Dopaminérgicos/farmacología , Ecolocación/efectos de los fármacos , 1-Metil-4-fenil-1,2,3,6-Tetrahidropiridina , Estimulación Acústica , Análisis de Varianza , Animales , Autorradiografía , Cromatografía Líquida de Alta Presión , Cuerpo Estriado/metabolismo , Dopaminérgicos/administración & dosificación , Ecolocación/fisiología , Inyecciones Intraperitoneales , Receptores Dopaminérgicos/metabolismo
19.
Regul Pept ; 172(1-3): 77-80, 2011 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-21903141

RESUMEN

AIMS: Ghrelin (GHR) is an orexigenic gut peptide that interacts with ghrelin receptors (GHR-Rs) to modulate brain reinforcement circuits. Systemic GHR infusions augment cocaine stimulated locomotion and conditioned place preference (CPP) in rats, whereas genetic or pharmacological ablation of GHR-Rs has been shown to attenuate the acute locomotor-enhancing effects of nicotine, cocaine, amphetamine and alcohol and to blunt the CPP induced by food, alcohol, amphetamine and cocaine in mice. The stimulant nicotine can induce CPP and like amphetamine and cocaine, repeated administration of nicotine induces locomotor sensitization in rats. A key issue is whether pharmacological antagonism of GHR-Rs would similarly attenuate nicotine-induced locomotor sensitization. METHOD: To examine the role of GHR-Rs in the behavioral sensitizing effects of nicotine, adult male rats were injected with either 0, 3 or 6 mg/kg of the GHR-R receptor antagonist JMV 2959 (i.p.) and 20 min later with either vehicle or 0.4 mg/kg nicotine hydrogen tartrate (s.c.) on each of 7 consecutive days. RESULTS: Rats treated with nicotine alone showed robust locomotor sensitization, whereas rats pretreated with JMV 2959 showed significantly attenuated nicotine-induced hyperlocomotion. CONCLUSIONS: These results suggest that GHR-R activity is required for the induction of locomotor sensitization to nicotine and complement an emerging literature implicating central GHR systems in drug reward/reinforcement.


Asunto(s)
Glicina/análogos & derivados , Actividad Motora/efectos de los fármacos , Nicotina/farmacología , Receptores de Ghrelina/antagonistas & inhibidores , Receptores de Ghrelina/metabolismo , Triazoles/farmacología , Animales , Glicina/farmacología , Masculino , Ratas , Ratas Sprague-Dawley
20.
Childs Nerv Syst ; 27(1): 145-8, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20490509

RESUMEN

INTRODUCTION: A myriad of geopolitical and financial obstacles have kept modern neurosurgery from effectively reaching the citizens of the developing world. Targeted neurosurgical outreach by academic neurosurgeons to equip neurosurgical operating theaters and train local neurosurgeons is one method to efficiently and cost effectively improve sustainable care provided by international charity hospitals. The International Neurosurgical Children's Association (INCA) effectively improved the available neurosurgical care in the Maria Auxiliadora Hospital of Lima, Peru through the advancement of local specialist education and training. METHODS: Neurosurgical equipment and training were provided for the local neurosurgeons by a mission team from the University of California at San Diego. RESULTS: At the end of 3 years, with one intensive week trip per year, the host neurosurgeons were proficiently and independently applying microsurgical techniques to previously performed operations, and performing newly learned operations such as neuroendoscopy and minimally invasive neurosurgery. CONCLUSION: Our experiences may serve as a successful template for the execution of other small scale, sustainable neurosurgery missions worldwide.


Asunto(s)
Relaciones Comunidad-Institución , Países en Desarrollo , Neurocirugia/educación , Organizaciones de Beneficencia , Hospitales , Humanos , Neurocirugia/instrumentación , Perú , Recursos Humanos
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