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1.
Pharm Res ; 40(7): 1641-1656, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36720831

RESUMEN

Administration of long-acting injectable suspensions is an increasingly common approach to increasing patient compliance and improving therapeutic efficacy through less frequent dosing. While several long-acting suspensions have recently been marketed, parameters modulating drug absorption from suspension-based formulations are not well understood. Further, methods for predicting clinical pharmacokinetic data from preclinical studies are not well established. Together, these limitations hamper compound selection, formulation design and formulation selection through heavy reliance on iterative optimization in preclinical and clinical studies. This article identifies key parameters influencing absorption from suspension-based formulations through compilation and analysis of preclinical and clinical pharmacokinetic data of seven compounds marketed as suspensions; achievable margins for predicting the clinical dose and input rate from preclinical studies as a function of the preclinical species, the clinical injection location and the intended therapeutic duration were also established.


Asunto(s)
Suspensiones , Humanos , Estudios Retrospectivos , Inyecciones
2.
Prog Mater Sci ; 1062019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32189815

RESUMEN

One of the goals of biomaterials science is to reverse engineer aspects of human and nonhuman physiology. Similar to the body's regulatory mechanisms, such devices must transduce changes in the physiological environment or the presence of an external stimulus into a detectable or therapeutic response. This review is a comprehensive evaluation and critical analysis of the design and fabrication of environmentally responsive cell-material constructs for bioinspired machinery and biomimetic devices. In a bottom-up analysis, we begin by reviewing fundamental principles that explain materials' responses to chemical gradients, biomarkers, electromagnetic fields, light, and temperature. Strategies for fabricating highly ordered assemblies of material components at the nano to macro-scales via directed assembly, lithography, 3D printing and 4D printing are also presented. We conclude with an account of contemporary material-tissue interfaces within bioinspired and biomimetic devices for peptide delivery, cancer theranostics, biomonitoring, neuroprosthetics, soft robotics, and biological machines.

3.
Int J Eat Disord ; 50(5): 593-596, 2017 05.
Artículo en Inglés | MEDLINE | ID: mdl-27753106

RESUMEN

OBJECTIVE: Individuals with anorexia nervosa (AN) have anxious and inhibited temperaments with high concern for consequences. Studies using either positron emission tomography (PET) or functional magnetic resonance imaging (fMRI) suggest involvement of the middle and dorsal caudate (DC) in individuals recovered (REC) from AN. For example, dopamine (DA) D2/D3 receptor binding in the middle caudate and DC was associated with anxiety and harm avoidance, and blood-oxygen-level-dependent (BOLD) response in the DC was positively related to trait anxiety. It has not been shown yet whether BOLD response in individuals REC from AN was related to DA function. METHODS: Post-hoc correlation analyses between the PET and fMRI studies by correlating D2/D3 binding in striatal regions and BOLD signal in the anteroventral striatum (AVS) and DC for wins and losses respectively in 12 individuals REC from AN. RESULTS: Individuals REC from AN with the greatest BOLD response in the DC in a monetary choice task had higher middle caudate D2/D3 binding, and greater anxiety and/or harm avoidance. DISCUSSION: Though preliminary, these findings suggest that increased dorsal striatal D2/D3 binding is associated with enhanced cognitive response to feedback, potentially related to anxious anticipation of consequences. © 2016 Wiley Periodicals, Inc.(Int J Eat Disord 2017; 50:593-596).


Asunto(s)
Anorexia Nerviosa/psicología , Dopamina/metabolismo , Imagen Multimodal/métodos , Receptores de Dopamina D2/metabolismo , Adulto , Femenino , Humanos , Masculino , Recompensa
4.
Int J Eat Disord ; 46(7): 701-8, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23818167

RESUMEN

OBJECTIVE: A recent study of ill individuals with anorexia nervosa (AN) reported microstructural alterations in white matter integrity including lower fractional anisotropy and higher mean diffusivity. This study was designed to determine whether such alterations exist in long-term recovered AN individuals and to examine potential associations with underlying AN traits. METHOD: Twelve adult women recovered from restricting-type AN and 10 control women were studied using diffusion tensor imaging. RESULTS: Overall, there was no significant fractional anisotropy alteration in recovered AN, in contrast to a prior study reporting lower fractional anisotropy in ill AN. Further, recovered AN showed lower mean diffusivity in frontal, parietal and cingulum white matter relative to control women, contrary to elevated mean diffusivity previously reported in ill AN. Lower longitudinal diffusivity in recovered AN was associated with higher harm avoidance. However, more severe illness history was associated with worse white matter integrity after recovery in the same direction as reported in prior work. DISCUSSION: Our findings suggest that fractional anisotropy in recovered AN is not different from controls, however, a novel pattern of lower mean diffusivity was evidenced in recovered AN, and this alteration was associated with harm avoidance. Notably, severity of illness history may have long-term consequences, emphasizing the importance of aggressive treatment.


Asunto(s)
Anorexia Nerviosa/patología , Encéfalo/patología , Fibras Nerviosas Mielínicas/patología , Adulto , Anisotropía , Anorexia Nerviosa/psicología , Encéfalo/anatomía & histología , Estudios de Casos y Controles , Imagen de Difusión Tensora , Femenino , Reducción del Daño , Humanos , Fibras Nerviosas Mielínicas/diagnóstico por imagen , Índice de Severidad de la Enfermedad , Ultrasonografía
5.
Int J Eat Disord ; 44(6): 477-87, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20872754

RESUMEN

OBJECTIVE: Because altered serotonin (5-HT) function appears to persist after recovery from bulimia nervosa (RBN), we investigated the 5-HT(1A) receptor, which could contribute to regulation of appetite, mood, impulse control, or the response to antidepressants. METHOD: Thirteen RBN individuals were compared to 21 healthy control women (CW) using positron emission tomography and [carbonyl-(11)C]WAY100635 ([(11)C]WAY). RESULTS: RBN had a 23-34% elevation of [(11)C]WAY binding potential (BP)(P) in subgenual cingulate, mesial temporal, and parietal regions after adjustments for multiple comparisons. For CW, [(11)C]WAY BP(P) was related negatively to novelty seeking, whereas for RBN, [(11)C]WAY BP(P) was related positively to harm avoidance and negatively related to sensation seeking. DISCUSSION: Alterations of 5-HT(1A) receptor function may provide new insight into efficacy of 5-HT medication in BN, as well as symptoms such as the ability to inhibit or self-control the expression of behaviors related to stimulus seeking, aggression, and impulsivity.


Asunto(s)
Encéfalo/diagnóstico por imagen , Bulimia Nerviosa/diagnóstico por imagen , Inhibición Psicológica , Receptor de Serotonina 5-HT1A/metabolismo , Recuperación de la Función , Adulto , Encéfalo/metabolismo , Bulimia Nerviosa/metabolismo , Femenino , Humanos , Cintigrafía
6.
Artículo en Inglés | MEDLINE | ID: mdl-34741934

RESUMEN

The potential of lipid nanoparticles (LNPs) as nucleic acid delivery vehicles has been demonstrated in recent years, culminating in the emergency use approval of LNP-based mRNA SARS-CoV-2 vaccines in late 2020. The determination of RNA content relative to LNP size can be important to the understanding of efficacy and adverse effects. This work presents the first description of a facile and rapid analytical method for online, size-dependent RNA payload distribution measurement using data from multi-angle light scattering, ultraviolet and refractive index detectors following separation of the LNPs by size-exclusion chromatography. The analysis was validated by size-based fractionation of the LNPs with subsequent offline analysis of the fractions. Four LNPs formulated with different PEG-lipids and different lipid compositions were tested. Good agreement was observed between the online and offline size-based RNA distributions among all four LNPs, demonstrating the utility of the online method for LNP-encapsulated RNA in general, and suggesting a means for simplified biophysical quantitation of a dosing-related critical quality attribute.


Asunto(s)
Vacunas contra la COVID-19/química , Cromatografía en Gel/métodos , Portadores de Fármacos/química , Nanopartículas/química , ARN Mensajero/química , ARN Viral/química , SARS-CoV-2/genética , COVID-19/virología , Vacunas contra la COVID-19/inmunología , Sistemas de Liberación de Medicamentos , Humanos , Lípidos/química , Tamaño de la Partícula , ARN Mensajero/inmunología , ARN Viral/inmunología , SARS-CoV-2/química , SARS-CoV-2/inmunología
7.
Int J Eat Disord ; 43(4): 289-94, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-19434606

RESUMEN

OBJECTIVE: It is possible that disturbances of systems modulating reward may contribute to a vulnerability to develop an eating disorder. METHOD: This hypothesis was tested by assessing functional magnetic resonance brain imaging response to a monetary reward task known to activate the anterior ventral striatum (AVS), a region implicated in motivational aspects toward stimuli. To avoid the confounding effects of malnutrition, 10 women who had recovered from bulimia nervosa (BN) were compared with 10 healthy comparison women (CW). RESULTS: For the AVS, CW distinguished positive and negative feedback, whereas recovered BN women had similar responses to both conditions. In addition, these groups had similar patterns of findings for the dorsal caudate. DISCUSSION: We have previously shown that individuals recovered from anorexia nervosa (AN) also had altered striatal responses and difficulties in differentiating positive and negative feedback. Thus BN and AN individuals may share a difficulty in discriminating the emotional significance of a stimulus.


Asunto(s)
Ganglios Basales/fisiopatología , Bulimia Nerviosa/fisiopatología , Bulimia Nerviosa/terapia , Imagen por Resonancia Magnética , Motivación , Recompensa , Adulto , Mapeo Encefálico , Emociones/fisiología , Retroalimentación Psicológica/fisiología , Femenino , Humanos , Valores de Referencia , Adulto Joven
8.
Tissue Eng Part A ; 26(23-24): 1226-1242, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32282291

RESUMEN

Bone tissue engineering strategies have been developed to address the limitations of the current gold standard treatment options for bone-related disorders. These systems consist of an engineered scaffold that mimics the extracellular matrix and provides an architecture to guide the natural bone regeneration process, and incorporated growth factors that enhance cell recruitment and ingress into the scaffold and promote the osteogenic differentiation of stem cells and angiogenesis. In particular, the osteogenic growth factor bone morphogenetic protein 2 (BMP-2) has been widely studied as a potent agent to improve bone regeneration. A key challenge in growth factor delivery is that the growth factors must reach their target sites without losing bioactivity and remain in the location for an extended period to effectively aid in the formation of new bone. Protein incorporation into nanoparticles can both protect protein bioactivity and enable its sustained release. In this study, a poly(methyl methacrylate-co-methacrylic acid) nanoparticle-based system was synthesized incorporating a custom poly(ethylene glycol) dimethacrylate crosslinker. It was demonstrated that the nanoparticle degradation rate can be controlled by tuning the number of hydrolytically degradable ester units along the crosslinker. We also showed that the nanoparticles had high affinity for a model protein for BMP-2, and optimal conditions for maximum protein loading efficiency were elucidated. Ultimately, the proposed system and its high degree of tunability can be applied to a wide range of growth factors and tissue engineering applications. Impact Statement In this study, we developed a novel method of synthesizing nanoparticles with tunable degradation rates through the incorporation of a custom synthesized, hydrolytically degradable crosslinker. In addition, we demonstrated the affinity of the synthesized nanoparticles for a model protein for bone morphogenetic protein 2 (BMP-2). The tunability of these nanoparticles can be used to develop complex tissue engineering systems, for example, for the delivery of multiple growth factors involved at different stages of the bone regeneration process.


Asunto(s)
Regeneración Ósea , Péptidos y Proteínas de Señalización Intercelular/administración & dosificación , Nanopartículas , Osteogénesis , Proteína Morfogenética Ósea 2 , Humanos , Metacrilatos , Polimetil Metacrilato , Andamios del Tejido
9.
J Biomed Mater Res A ; 108(5): 1122-1135, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-31971334

RESUMEN

To guide the natural bone regeneration process, bone tissue engineering strategies rely on the development of a scaffold architecture that mimics the extracellular matrix and incorporates important extracellular signaling molecules, which promote fracture healing and bone formation pathways. Incorporation of growth factors into particles embedded within the scaffold can offer both protection of protein bioactivity and a sustained release profile. In this work, a novel method to immobilize carrier nanoparticles within scaffold pores is proposed. A biodegradable, osteoconductive, porous chitosan scaffold was fabricated via the "freeze-drying method," leading to scaffolds with a storage modulus of 8.5 kPa and 300 µm pores, in line with existing bone scaffold properties. Next, poly(methyl methacrylate-co-methacrylic acid) nanoparticles were synthesized and immobilized to the scaffold via carbodiimide-crosslinker chemistry. A fluorescent imaging study confirmed that the conventional methods of protein and nanocarrier incorporation into scaffolds can lead to over 60% diffusion out of the scaffold within the first 5 min of implantation, and total disappearance within 4 weeks. The novel method of nanocarrier immobilization to the scaffold backbone via carbodiimide-crosslinker chemistry allows full retention of particles for up to 4 weeks within the scaffold bulk, with no negative effects on the viability and proliferation of human umbilical vein endothelial cells.


Asunto(s)
Materiales Biocompatibles/química , Quitosano/química , Preparaciones de Acción Retardada/química , Péptidos y Proteínas de Señalización Intercelular/administración & dosificación , Andamios del Tejido/química , Implantes Absorbibles , Células Endoteliales de la Vena Umbilical Humana , Humanos , Péptidos y Proteínas de Señalización Intercelular/farmacología , Osteogénesis/efectos de los fármacos , Porosidad , Ingeniería de Tejidos
10.
Z Kinder Jugendpsychiatr Psychother ; 37(5): 413-20, 2009 Sep.
Artículo en Alemán | MEDLINE | ID: mdl-19739059

RESUMEN

BACKGROUND: The chronic abuse of Gamma-Hydroxybutyrate (GHB) as a designer drug as well as it's physiological precursors Gamma-Butyrolactone (GBL) and 1,4-Butandiole (1,4-BD) confronts child and adolescent psychiatrists with new challenges. The acute withdrawal of GHB with its cardiovascular and delirant symptoms is of particular importance for child and adolescent psychiatrists. METHODS: In the present paper theoretical and biological aspects of acute GHB-/GBL-/1,4-BD-withdrawal syndrome are presented, and selected cases are discussed as regards potential treatment. RESULTS: High dose treatment with benzodiazepines was successful in some cases of acute GHB-/GBL-/1,4-BD-withdrawal syndrome. Complications were severe dystonia under neuroleptic treatment, and also side-effects of treatment with benzodiazepines. Further problems were vegetative symptoms, electrocardiographic changes, rhabdomyolysis, acute renal failure, and death. CONCLUSION: Acute GHB-withdrawal syndrome is a life-threatening condition which requires immediate intensive care treatment along with continuous monitoring of vital parameters. As acute GHB-withdrawal syndrome can present with symptoms close to psychotic episodes or acute alcohol withdrawal this condition is relevant for child and adolescent psychiatrists.


Asunto(s)
Anestésicos Intravenosos/efectos adversos , Deluciones/inducido químicamente , Oxibato de Sodio/efectos adversos , Síndrome de Abstinencia a Sustancias/diagnóstico , Trastornos Relacionados con Sustancias/rehabilitación , 4-Butirolactona/efectos adversos , Enfermedad Aguda , Adolescente , Antipsicóticos/efectos adversos , Antipsicóticos/uso terapéutico , Benzodiazepinas/efectos adversos , Benzodiazepinas/uso terapéutico , Butileno Glicoles/efectos adversos , Niño , Cuidados Críticos , Deluciones/diagnóstico , Deluciones/tratamiento farmacológico , Diagnóstico Diferencial , Interacciones Farmacológicas , Humanos , Psicosis Inducidas por Sustancias/diagnóstico , Psicosis Inducidas por Sustancias/tratamiento farmacológico , Síndrome de Abstinencia a Sustancias/tratamiento farmacológico
11.
Acta Biomater ; 94: 44-63, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31082570

RESUMEN

Semiconducting nanoparticles, more commonly known as quantum dots, possess unique size and shape dependent optoelectronic properties. In recent years, these unique properties have attracted much attention in the biomedical field to enable real-time tissue imaging (bioimaging), diagnostics, single molecule probes, and drug delivery, among many other areas. The optical properties of quantum dots can be tuned by size and composition, and their high brightness, resistance to photobleaching, multiplexing capacity, and high surface-to-volume ratio make them excellent candidates for intracellular tracking, diagnostics, in vivo imaging, and therapeutic delivery. We discuss recent advances and challenges in the molecular design of quantum dots are discussed, along with applications of quantum dots as drug delivery vehicles, theranostic agents, single molecule probes, and real-time in vivo deep tissue imaging agents. We present a detailed discussion of the biodistribution and toxicity of quantum dots, and highlight recent advances to improve long-term stability in biological buffers, increase quantum yield following bioconjugation, and improve clearance from the body. Last, we present an outlook on future challenges and strategies to further advance translation to clinical application. STATEMENT OF SIGNIFICANCE: Semiconducting nanoparticles, commonly known as quantum dots, possess unique size and shape dependent electrical and optical properties. In recent years, they have attracted much attention in biomedical imaging to enable diagnostics, single molecule probes, and real-time imaging of tumors. This review discusses recent advances and challenges in the design of quantum dots, and highlights how these strategies can further advance translation to clinical applications.


Asunto(s)
Materiales Biocompatibles/química , Sistemas de Liberación de Medicamentos , Nanotecnología/métodos , Nanotecnología/tendencias , Puntos Cuánticos , Animales , Colorantes Fluorescentes/química , Humanos , Ligandos , Ratones Desnudos , Nanopartículas , Óptica y Fotónica , Semiconductores , Nanomedicina Teranóstica , Distribución Tisular
12.
Neuropsychopharmacology ; 33(3): 513-23, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17487228

RESUMEN

Anorexia nervosa (AN) is an illness characterized by aversion to ingestion of normally palatable foods. We examined whether there is a primary disturbance of taste processing and experience of pleasure using a sucrose/water task in conjunction with functional magnetic resonance imaging (fMRI). To avoid confounding effects of illness, 16 women recovered from restricting-type AN were compared to 16 control women (CW). We used a region of interest-based fMRI approach to test the idea that individuals with AN have differential neural activation in primary and secondary taste cortical regions after sucrose and water administration. Compared to CW, individuals recovered from AN showed a significantly lower neural activation of the insula, including the primary cortical taste region, and ventral and dorsal striatum to both sucrose and water. In addition, insular neural activity correlated with pleasantness ratings for sucrose in CW, but not in AN subjects. Altered taste processing may occur in AN, based on differences in activity in insular-striatal circuits. These data provide the first evidence that individuals with AN process taste stimuli differently than controls, based on differences in neural activation patterns.


Asunto(s)
Anorexia Nerviosa/fisiopatología , Anorexia Nerviosa/psicología , Corteza Cerebral/fisiopatología , Gusto/fisiología , Adulto , Ansiedad/psicología , Índice de Masa Corporal , Carbohidratos , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Escalas de Valoración Psiquiátrica , Agua
13.
Z Kinder Jugendpsychiatr Psychother ; 36(3): 177-84, 2008 May.
Artículo en Alemán | MEDLINE | ID: mdl-18622977

RESUMEN

BACKGROUND: Family studies of anorexia (AN) and bulimia (BN) nervosa in relatives of patients with eating disorders compared to control subjects are rare in German-speaking countries. METHODS: A German multicenter study compared first-, second- and third-degree relatives of 65 adolescent AN subjects (n = 746), 21 adolescent BN subjects (n = 265) and relatives of 11 adolescent depressive control subjects (n = 157), as well as those of 37 adolescent healthy control subjects (n = 480). Assessments included the Diagnostic Interview for Genetic Studies (DIGS), the short form of the Family Interview of Genetic Studies (FIGS), and the Eating Disorder Family History Interview. RESULTS: Rates of anorexia nervosa and major depressive disorder (trend) were significantly (p < .01) higher among the first- and second-degree relatives of anorexic and bulimic subjects than among the relatives of healthy controls. Most results were more prominent among relatives of bulimic index patients. Nevertheless, the frequencies were lower in this sample than in comparable US-American samples. CONCLUSIONS: The data confirm the hypothesis of familial vulnerability to anorexia and bulimia nervosa. The observed differences in comorbidity patterns among eating-disordered relatives may be due to an age effect of the index patients.


Asunto(s)
Anorexia Nerviosa/genética , Bulimia Nerviosa/genética , Trastornos Mentales/genética , Adolescente , Alcoholismo/diagnóstico , Alcoholismo/genética , Anorexia Nerviosa/diagnóstico , Trastornos de Ansiedad/diagnóstico , Trastornos de Ansiedad/genética , Bulimia Nerviosa/diagnóstico , Niño , Comparación Transcultural , Trastorno Depresivo Mayor/diagnóstico , Trastorno Depresivo Mayor/genética , Femenino , Predisposición Genética a la Enfermedad/genética , Alemania , Humanos , Masculino , Trastornos Mentales/diagnóstico , Trastorno Obsesivo Compulsivo/diagnóstico , Trastorno Obsesivo Compulsivo/genética , Trastornos Relacionados con Sustancias/diagnóstico , Trastornos Relacionados con Sustancias/genética
14.
J Appl Polym Sci ; 135(24)2018 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-30174339

RESUMEN

In recent decades, nanoparticles have shown significant promise as an oncology treatment modality. Responsive polymers represent a promising class of nanoparticles that can trigger delivery through the exploitation of a specific stimuli. Response to a stimulus is one of the most basic processes found in living systems. As such, the desire to engineer dynamic and functional materials is becoming more prevalent in an effort to achieve precise control over our environment. The combination of controlled radical polymerization and high yielding chemistry strategies provide an excellent basis for the development of the next generation of drug delivery systems. The versatility of polymer chemistries available enables the synthesis of increasingly complex architectures with enhanced delivery specificity and control over the desired properties to interface with biological systems. This tutorial review highlights recent developments in polymer-based approaches to internally responsive nanoparticles for oncology. Presented are concise overviews of the current challenges and opportunities in cancer nanomedicine, common polymer-based architectures, and the basis for internally triggered stimuli-response relationships commonly employed in oncology applications. Examples of the chemistry used in the design of environmentally labile nanomaterials are discussed, and we outline recent advances in creating advanced bioresponsive drug delivery architectures.

15.
Acta Pharm Sin B ; 8(2): 147-164, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29719776

RESUMEN

Therapeutic proteins and peptides have revolutionized treatment for a number of diseases, and the expected increase in macromolecule-based therapies brings a new set of challenges for the pharmaceutics field. Due to their poor stability, large molecular weight, and poor transport properties, therapeutic proteins and peptides are predominantly limited to parenteral administration. The short serum half-lives typically require frequent injections to maintain an effective dose, and patient compliance is a growing issue as therapeutic protein treatments become more widely available. A number of studies have underscored the relationship of subcutaneous injections with patient non-adherence, estimating that over half of insulin-dependent adults intentionally skip injections. The development of oral formulations has the potential to address some issues associated with non-adherence including the interference with daily activities, embarrassment, and injection pain. Oral delivery can also help to eliminate the adverse effects and scar tissue buildup associated with repeated injections. However, there are several major challenges associated with oral delivery of proteins and peptides, such as the instability in the gastrointestinal (GI) tract, low permeability, and a narrow absorption window in the intestine. This review provides a detailed overview of the oral delivery route and associated challenges. Recent advances in formulation and drug delivery technologies to enhance bioavailability are discussed, including the co-administration of compounds to alter conditions in the GI tract, the modification of the macromolecule physicochemical properties, and the use of improved targeted and controlled release carriers.

16.
Acta Biomater ; 76: 193-207, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29940370

RESUMEN

α-Galactosylceramide (GalCer) is a glycolipid widely known as an activator of Natural killer T (NKT) cells, constituting a promising adjuvant against cancer, including melanoma. However, limited clinical outcomes have been obtained so far. This study evaluated the synergy between GalCer and major histocompatibility complex (MHC) class I and MHC class II melanoma-associated peptide antigens and the Toll-Like Receptor (TLR) ligands CpG and monophosphoryl lipid A (MPLA), which we intended to maximize following their co-delivery by a nanoparticle (NP). This is expected to improve GalCer capture by dendritic cells (DCs) and subsequent presentation to NKT cells, simultaneously inducing an anti-tumor specific T-cell mediated immunity. The combination of GalCer with melanoma peptides and TLR ligands successfully restrained tumor growth. The tumor volume in these animals was 5-fold lower than the ones presented by mice immunized with NPs not containing GalCer. However, tumor growth was controlled at similar levels by GalCer entrapped or in its soluble form, when mixed with antigens and TLR ligands. Those two groups showed an improved infiltration of T lymphocytes into the tumor, but only GalCer-loaded nano-vaccine induced a prominent and enhanced infiltration of NKT and NK cells. In addition, splenocytes of these animals secreted levels of IFN-γ and IL-4 at least 1.5-fold and 2-fold higher, respectively, than those treated with the mixture of antigens and adjuvants in solution. Overall, the combined delivery of the NKT agonist with TLR ligands and melanoma antigens via this multivalent nano-vaccine displayed a synergistic anti-tumor immune-mediated efficacy in B16F10 melanoma mouse model. STATEMENT OF SIGNIFICANCE: Combination of α-galactosylceramide (GalCer), a Natural Killer T (NKT) cell agonist, with melanoma-associated antigens presented by MHC class I (Melan-A:26) and MHC class II (gp100:44) molecules, and Toll-like Receptor (TLR) ligands (MPLA and CpG), within nanoparticle matrix induced a prominent anti-tumor immune response able to restrict melanoma growth. An enhanced infiltration of NKT and NK cells into tumor site was only achieved when the combination GalCer, antigens and TLR ligands were co-delivered by the nanovaccine.


Asunto(s)
Vacunas contra el Cáncer , Galactosilceramidas , Inmunidad Celular/efectos de los fármacos , Melanoma Experimental/terapia , Nanopartículas , Péptidos , Animales , Vacunas contra el Cáncer/química , Vacunas contra el Cáncer/farmacocinética , Vacunas contra el Cáncer/farmacología , Línea Celular Tumoral , Células Dendríticas/inmunología , Células Dendríticas/patología , Galactosilceramidas/química , Galactosilceramidas/farmacocinética , Galactosilceramidas/farmacología , Células Asesinas Naturales/inmunología , Células Asesinas Naturales/patología , Masculino , Melanoma Experimental/inmunología , Melanoma Experimental/patología , Ratones , Ratones Endogámicos C57BL , Nanopartículas/química , Nanopartículas/uso terapéutico , Péptidos/química , Péptidos/farmacocinética , Péptidos/farmacología , Linfocitos T/inmunología , Linfocitos T/patología , Receptores Toll-Like/inmunología
17.
Biol Psychiatry ; 61(9): 1090-9, 2007 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-17241616

RESUMEN

BACKGROUND: Many studies have found disturbances of serotonin (5-HT) activity in anorexia nervosa (AN). Because little is known about 5-HT receptor function in AN, positron emission tomography (PET) imaging with 5-HT receptor-specific radioligands was used to characterize 5-HT1A and 5-HT2A receptors. METHODS: Fifteen women ill with AN (ILL AN) were compared with 29 healthy control women (CW); PET and [11C]WAY100635 were used to assess binding potential (BP) of the 5-HT1A receptor, and [18F]altanserin was used to assess postsynaptic 5-HT2A receptor BP. [15O] water and PET were used to assess cerebral blood flow. RESULTS: The ILL AN women had a highly significant (30%-70%) increase in [11C]WAY100635 BP in prefrontal and lateral orbital frontal regions, mesial and lateral temporal lobes, parietal cortex, and dorsal raphe nuclei compared with CW. The [18F]altanserin BP was normal in ILL AN but was positively and significantly related to harm avoidance in suprapragenual cingulate, frontal, and parietal regions. Cerebral blood flow was normal in ILL AN women. CONCLUSIONS: Increased activity of 5-HT1A receptor activity may help explain poor response to 5-HT medication in ILL AN. This study extends data suggesting that 5-HT function, and, specifically, the 5-HT2A receptor, is related to anxiety in AN.


Asunto(s)
Anorexia Nerviosa/metabolismo , Receptor de Serotonina 5-HT1A/metabolismo , Receptor de Serotonina 5-HT2A/metabolismo , Adulto , Anorexia Nerviosa/diagnóstico por imagen , Anorexia Nerviosa/fisiopatología , Circulación Cerebrovascular/fisiología , Interpretación Estadística de Datos , Femenino , Humanos , Ketanserina/análogos & derivados , Imagen por Resonancia Magnética , Radioisótopos de Oxígeno , Piperazinas , Tomografía de Emisión de Positrones , Piridinas , Antagonistas de la Serotonina
18.
Am J Psychiatry ; 164(12): 1842-9, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18056239

RESUMEN

OBJECTIVE: Individuals with anorexia nervosa are known to be ascetic and able to sustain self-denial of food as well as most comforts and pleasures in life. Building on previous findings of altered striatal dopamine binding in anorexia nervosa, the authors sought to assess the response of the anterior ventral striatum to reward and loss in this disorder. METHOD: Striatal responses to a simple monetary reward task were investigated using event-related functional magnetic resonance imaging. To avoid the confounding effects of malnutrition, the authors compared 13 healthy comparison women and 13 women who had recovered from restricting-type anorexia nervosa and had 1 year of normal weight and regular menstrual cycles, without binge eating or purging. RESULTS: Recovered women showed greater hemodynamic activation in the caudate than comparison women. Only the recovered women showed a significant positive relationship between trait anxiety and the percentage change in hemodynamic signal in the caudate during either wins or losses. In contrast, in the anterior ventral striatum, comparison women distinguished positive and negative feedback, whereas recovered women had similar responses to both conditions. CONCLUSIONS: Individuals who have recovered from anorexia nervosa may have difficulties in differentiating positive and negative feedback. The exaggerated activation of the caudate, a region involved in linking action to outcome, may constitute an attempt at "strategic" (as opposed to hedonic) means of responding to reward stimuli. The authors hypothesize that individuals with anorexia nervosa have an imbalance in information processing, with impaired ability to identify the emotional significance of a stimulus but increased traffic in neurocircuits concerned with planning and consequences.


Asunto(s)
Anorexia Nerviosa/diagnóstico , Ganglios Basales/fisiología , Recompensa , Adulto , Anorexia Nerviosa/fisiopatología , Anorexia Nerviosa/psicología , Índice de Masa Corporal , Peso Corporal , Mapeo Encefálico , Núcleo Caudado/irrigación sanguínea , Núcleo Caudado/fisiología , Discriminación en Psicología/fisiología , Potenciales Evocados/fisiología , Retroalimentación/fisiología , Femenino , Lateralidad Funcional/fisiología , Juego de Azar/psicología , Juegos Experimentales , Hemodinámica/fisiología , Humanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética/estadística & datos numéricos , Estado Nutricional , Oxígeno/sangre , Resultado del Tratamiento
19.
Psychopharmacology (Berl) ; 195(3): 315-24, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17690869

RESUMEN

RATIONALE: Several lines of evidence suggest that altered serotonin (5-HT) function persists after recovery from anorexia nervosa (AN) and bulimia nervosa (BN). OBJECTIVES: We compared 11 subjects who recovered (>1 year normal weight, regular menstrual cycles, no binging or purging) from restricting-type AN (REC RAN), 7 who recovered from bulimia-type AN (REC BAN), 9 who recovered from BN (REC BN), and 10 healthy control women (CW). MATERIALS AND METHODS: Positron emission tomography (PET) imaging with [11C]McN5652 was used to assess the 5-HT transporter (5-HTT). For [11C]McN5652, distribution volume (DV) values were determined using a two-compartment, three-parameter tracer kinetic model, and specific binding was assessed using the binding potential (BP, BP=DVregion of interest/DVcerebellum-1). RESULTS: After correction for multiple comparisons, the four groups showed significant (p<0.05) differences for [11C]McN5652 BP values for the dorsal raphe and antero-ventral striatum (AVS). Post-hoc analysis revealed that REC RAN had significantly increased [11C]McN5652 BP compared to REC BAN in these regions. CONCLUSIONS: Divergent 5-HTT activity in subtypes of eating disorder subjects may provide important insights as to why these groups have differences in affective regulation and impulse control.


Asunto(s)
Anorexia Nerviosa/metabolismo , Encéfalo/metabolismo , Bulimia Nerviosa/metabolismo , Proteínas de Transporte de Serotonina en la Membrana Plasmática/metabolismo , Adulto , Encéfalo/diagnóstico por imagen , Radioisótopos de Carbono , Femenino , Genotipo , Humanos , Isoquinolinas , Cinética , Imagen por Resonancia Magnética , Especificidad de Órganos , Polimorfismo Genético , Tomografía de Emisión de Positrones , Regiones Promotoras Genéticas , Radiofármacos
20.
Biol Psychiatry ; 59(3): 291-3, 2006 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-16139807

RESUMEN

BACKGROUND: Individuals who are ill with anorexia (AN) and bulimia nervosa (BN) often have increased cerebrospinal fluid (CSF) volumes and decreased total gray and white matter volumes. It is unclear whether such disturbances persist after recovery from an eating disorder. METHODS: Magnetic resonance imaging was performed on 40 women who were long-term recovered (>1 year no binging, purging, or restricting behaviors, normal weight, and menstrual cycles, not on medication) from restricting or binge/purging type AN or BN and 31 healthy control women (CW). Voxel-based morphometry (VBM) was used for data analysis. RESULTS: Recovered AN and BN subgroups were similar to CW in terms of cerebrospinal fluid (CSF) volume as well as total or regional gray or white matter volume. CONCLUSIONS: These findings suggest that structural brain abnormalities are reversible in individuals with eating disorders after long-term recovery.


Asunto(s)
Anorexia Nerviosa/patología , Encéfalo/patología , Bulimia/patología , Bulimia/rehabilitación , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Adolescente , Adulto , Anorexia Nerviosa/rehabilitación , Atrofia , Ventrículos Cerebrales/patología , Líquido Cefalorraquídeo/fisiología , Femenino , Estudios de Seguimiento , Humanos , Recuperación de la Función/fisiología
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