RESUMEN
Romantic relationships help people meet needs for connection and emotional and sexual fulfillment. In the current research, we investigate an unexplored response to feeling sexually and relationally unfulfilled: reflecting on positive sexual experiences with past partners (or sexual nostalgia). Across three studies, people low in attachment avoidance (i.e., comfortable with closeness) who were (a) single or (b) sexually or relationally dissatisfied reported greater sexual nostalgia, whereas people high in attachment avoidance (i.e., value autonomy) did not calibrate their feelings of sexual nostalgia based on their current relationship status or satisfaction. Sexual fantasies about past partners (i.e., sexual nostalgia) were distinct from other types of sexual fantasies (Study 1) and the effects could not be attributed to general nostalgia (Study 2) or sexual desire (Study 3). Chronic sexual nostalgia detracted from satisfaction over time. The findings have implications for theories of nostalgia and attachment and for managing unfulfilled needs in relationships.
Asunto(s)
Apego a Objetos , Satisfacción Personal , Conducta Sexual/psicología , Parejas Sexuales/psicología , Adulto , Anciano , Reacción de Prevención , Emociones , Femenino , Humanos , Relaciones Interpersonales , Masculino , Persona de Mediana Edad , Atención Plena , Encuestas y Cuestionarios , Adulto JovenRESUMEN
CONTEXT: Limited ankle dorsiflexion (DF) range of motion has been correlated with decreased flexibility of the gastrocnemius/soleus complex. Decreased ankle DF range of motion can lead to an increase in lower-extremity injuries, for example, acute ankle sprains, Achilles tendinopathy. OBJECTIVE: The purpose of this study was to determine whether a single application of the intervention to the gastrocnemius/soleus complex via multidirectional self-myofascial release using a foam roller, multiplanar dynamic stretch performed in downward dog, or a combination of both techniques acutely improved ankle DF. DESIGN: Subjects were assigned to groups via random card selection. Investigators provided verbal cues as needed to yield correct performance of interventions. Both interventions were performed twice for 1 minute using a dynamic walking rest of 30.48 m at a self-selected pace between interventions. Statistical analyses were completed using a 1-way analysis of variance, at α level ≤ .05. SETTING: A convenience sample study. PARTICIPANTS: A total of 42 asymptomatic physical therapy students (18 females and 24 males) with mean age of 26.12 (4.03) years volunteered to participate. INTERVENTIONS: Multidirectional self-myofascial release using a foam roller, multiplanar dynamic stretch performed in downward dog, or a combination of both techniques. MAIN OUTCOME MEASURES: Weight-bearing right ankle DF measurements were recorded in centimeters using a forward lunge technique (intraclass correlation coefficient = .98, .97, and .96). RESULTS: Data analysis revealed no significant difference between the 3 groups in all pre-post measurements (P = .82). Mean (SD) measurements from pretest to posttest for myofascial release, dynamic stretching, and combination interventions were 0.479 (0.7) cm, 0.700 (0.7) cm, and 0.907 (1.4) cm, respectively. CONCLUSION: Until further studies are conducted, the selection of technique to increase ankle DF range of motion should be based on each individual patient's ability, preference, and response to treatment.
Asunto(s)
Articulación del Tobillo/fisiología , Masaje/métodos , Ejercicios de Estiramiento Muscular/fisiología , Músculo Esquelético/fisiología , Rango del Movimiento Articular/fisiología , Adulto , Traumatismos del Tobillo/prevención & control , Femenino , Voluntarios Sanos , Humanos , Masculino , Masaje/instrumentación , Adulto JovenRESUMEN
A key function of the nucleus accumbens is to promote vigorous reward seeking, but the corresponding neural mechanism has not been identified despite many years of research. Here, we study cued flexible approach behavior, a form of reward seeking that strongly depends on the accumbens, and we describe a robust, single-cell neural correlate of behavioral vigor in the excitatory response of accumbens neurons to reward-predictive cues. Well before locomotion begins, this cue-evoked excitation predicts both the movement initiation latency and the speed of subsequent flexible approach responses, but not those of stereotyped, inflexible responses. Moreover, the excitation simultaneously signals the subject's proximity to the approach target, a signal that appears to mediate greater response vigor on trials that begin with the subject closer to the target. These results demonstrate a neural mechanism for response invigoration whereby accumbens neuronal encoding of reward availability and target proximity together drive the onset and speed of reward-seeking locomotion.
Asunto(s)
Condicionamiento Operante/fisiología , Señales (Psicología) , Neuronas/fisiología , Núcleo Accumbens/fisiología , Recompensa , Estimulación Acústica , Potenciales de Acción/fisiología , Animales , Mapeo Encefálico , Discriminación en Psicología , Electrodos Implantados , Lateralidad Funcional , Locomoción/fisiología , Modelos Biológicos , Núcleo Accumbens/citología , Orientación , Análisis de Componente Principal , Ratas , Tiempo de Reacción/fisiología , Grabación de Cinta de VideoRESUMEN
Binge eating disorders are characterized by discrete episodes of rapid and excessive food consumption. In rats, giving intermittent access to sweet fat food mimics this aspect of binge eating. These models typically employ solid food; however, the total amount consumed depends on motivation, palatability and satiety, which are difficult to dissociate with solid food. In contrast, lick microstructure analysis can be used to dissociate these parameters when the ingestant is a liquid. Therefore, we developed a binge model using a liquid emulsion composed of corn oil, heavy cream and sugar. We show that rats given intermittent access to this high-fat emulsion develop binge-like behavior comparable to that previously observed with solid high-fat food. One feature of this behavior was a gradual escalation in consumption across 2.5 weeks of intermittent access, which was not apparent in rats given lower-fat liquid on the same access schedule. Lick microstructure analysis suggests that this escalation was due at least in part to increases in both motivation to consume and palatability-driven consumption.
Asunto(s)
Bulimia/psicología , Grasas de la Dieta/administración & dosificación , Conducta Alimentaria/psicología , Preferencias Alimentarias/psicología , Motivación/fisiología , Respuesta de Saciedad/fisiología , Estimulación Acústica , Análisis de Varianza , Animales , Peso Corporal , Bulimia/fisiopatología , Modelos Animales de Enfermedad , Masculino , Ratas , Ratas Long-Evans , Edulcorantes/administración & dosificación , Factores de TiempoRESUMEN
Peripheral nerve injuries lead to a variety of pathological conditions, including paresis or paralysis when the injury involves motor axons. We have been studying ways to enhance the regeneration of peripheral nerves using daily electrical stimulation (ES) following a facial nerve crush injury. In our previous studies, ES was not initiated until 24 h after injury. The current experiment tested whether ES administered immediately following the crush injury would further decrease the time for complete recovery from facial paralysis. Rats received a unilateral facial nerve crush injury and an electrode was positioned on the nerve proximal to the crush site. Animals received daily 30 min sessions of ES for 1 d (day of injury only), 2 d, 4 d, 7 d, or daily until complete functional recovery. Untreated animals received no ES. Animals were observed daily for the return of facial function. Our findings demonstrated that one session of ES was as effective as daily stimulation at enhancing the recovery of most functional parameters. Therefore, the use of a single 30 min session of ES as a possible treatment strategy should be studied in human patients with paralysis as a result of acute nerve injuries.
Asunto(s)
Terapia por Estimulación Eléctrica , Traumatismos del Nervio Facial/terapia , Nervio Facial/fisiología , Parálisis Facial/terapia , Animales , Estimulación Eléctrica/métodos , Traumatismos del Nervio Facial/fisiopatología , Parálisis Facial/fisiopatología , Regeneración Nerviosa/fisiología , Ratas , Ratas Sprague-Dawley , Recuperación de la Función , Vibrisas/inervaciónRESUMEN
BACKGROUND: Testicular toxicity (TT) is a sporadic and challenging issue in pharmaceutical drug development. Efforts to develop TT screening assays or biomarkers have been overshadowed by consortium efforts to predict drug-induced toxicities such as hepatic injury, which are encountered more frequently. METHODS: To gauge the current state of the field and to prioritize future TT activities, the International Life Sciences Institute-Health and Environmental Sciences Institute Developmental and Reproductive Toxicology (DART) Technical Committee sponsored a survey to better understand the incidence and nature of TT findings encountered during drug development. RESULTS: Highlights from the 16 survey respondents include: (1) Although preclinical TT was encountered relatively infrequently, half of the participants observed repeated problems with TT during pharmaceutical development, (2) despite control measures such as use of sexually mature animals to diminish confounding effects of spurious lesions, interpretation of TT remains a challenge, (3) "traditional" evaluation tools such as hormonal monitoring and newer approaches such as -omics are utilized to investigate testicular changes, and (4) an understanding of the risk and relevance of TT findings is achieved through joint consideration of factors such as species specificity, potential mode of action, and safety margins. CONCLUSIONS: TT remains a relatively uncommon but persistent challenge in pharmaceutical development. Although current preclinical TT approaches appear to be effective in limiting the occurrence of pharmaceutical candidate attrition in clinical trials, improved biomarker or screening platforms would allow companies to identify TT at an earlier stage, thus decreasing the time and resources expended on safety evaluation of pharmaceutical candidates.
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Diseño de Fármacos , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Preparaciones Farmacéuticas/metabolismo , Testículo/efectos de los fármacos , Pruebas de Toxicidad , Animales , Evaluación Preclínica de Medicamentos , Humanos , MasculinoRESUMEN
The Developmental and Reproductive Toxicology Technical Committee of the ILSI Health and Environmental Sciences Institute has undertaken a project to address the impact of juvenile animal studies on pediatric drug development. A workshop, sponsored and organized by the Health and Environmental Sciences Institute Developmental and Reproductive Toxicity Technical Committee, was held on May 5-6, 2010, in Washington, DC, to discuss the outcome of a global survey and the value of juvenile animal studies in the development of drugs intended for use in pediatric patients. During this workshop, summary data from the 2009-2010 survey were presented, and breakout sessions were used to discuss specific case studies to try to assess the impact of juvenile animal studies performed to support specific pediatric drug development. The objectives of the Workshop on The Value of Juvenile Animal Studies were to (1) provide a forum for scientists representing industry, academia, and regulatory agencies to discuss the impact of juvenile animal studies on pediatric drug development, (2) evaluate summary data from the survey to understand how the juvenile study data are being used and their impact in labeling and risk assessment, (3) discuss selected case studies from the survey to highlight key findings, and (4) identify the areas of improvement for the designs of juvenile animal studies. The take home message that resonated from the workshop discussions was that well-designed juvenile animal studies have demonstrated value in support of certain pediatric drug development programs. However, it was also clear that a juvenile animal study is not always warranted.
Asunto(s)
Animales de Laboratorio/crecimiento & desarrollo , Evaluación Preclínica de Medicamentos , Modelos Animales , Animales , Medición de Riesgo , Pruebas de ToxicidadRESUMEN
Thiamin and thiamin pyrophosphate (TPP) are well known for their important roles in human nutrition and enzyme catalysis. In this work, we present new evidence for an additional role of these compounds in the protection of cells against oxidative damage. Arabidopsis (Arabidopsis thaliana) plants subjected to abiotic stress conditions, such as high light, cold, osmotic, salinity, and oxidative treatments, accumulated thiamin and TPP. Moreover, the accumulation of these compounds in plants subjected to oxidative stress was accompanied by enhanced expression of transcripts encoding thiamin biosynthetic enzymes. When supplemented with exogenous thiamin, wild-type plants displayed enhanced tolerance to oxidative stress induced by paraquat. Thiamin application was also found to protect the reactive oxygen species-sensitive ascorbate peroxidase1 mutant from oxidative stress. Thiamin-induced tolerance to oxidative stress was accompanied by decreased production of reactive oxygen species in plants, as evidenced from decreased protein carbonylation and hydrogen peroxide accumulation. Because thiamin could protect the salicylic acid induction-deficient1 mutant against oxidative stress, thiamin-induced oxidative protection is likely independent of salicylic acid signaling or accumulation. Taken together, our studies suggest that thiamin and TPP function as important stress-response molecules that alleviate oxidative stress during different abiotic stress conditions.
Asunto(s)
Arabidopsis/efectos de los fármacos , Arabidopsis/fisiología , Estrés Oxidativo/fisiología , Tiamina/farmacología , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Regulación de la Expresión Génica de las Plantas/fisiología , Mutación , Oxidación-Reducción , Especies Reactivas de Oxígeno , Ácido Salicílico/metabolismo , Plantones/fisiologíaRESUMEN
Ca2+ has been proposed to regulate Na+ channels through the action of calmodulin (CaM) bound to an IQ motif or through direct binding to a paired EF hand motif in the Nav1 C terminus. Mutations within these sites cause cardiac arrhythmias or autism, but details about how Ca2+ confers sensitivity are poorly understood. Studies on the homologous Cav1.2 channel revealed non-canonical CaM interactions, providing a framework for exploring Na+ channels. In contrast to previous reports, we found that Ca2+ does not bind directly to Na+ channel C termini. Rather, Ca2+ sensitivity appears to be mediated by CaM bound to the C termini in a manner that differs significantly from CaM regulation of Cav1.2. In Nav1.2 or Nav1.5, CaM bound to a localized region containing the IQ motif and did not support the large Ca(2+)-dependent conformational change seen in the Cav1.2.CaM complex. Furthermore, CaM binding to Nav1 C termini lowered Ca2+ binding affinity and cooperativity among the CaM-binding sites compared with CaM alone. Nonetheless, we found suggestive evidence for Ca2+/CaM-dependent effects upon Nav1 channels. The R1902C autism mutation conferred a Ca(2+)-dependent conformational change in Nav1.2 C terminus.CaM complex that was absent in the wild-type complex. In Nav1.5, CaM modulates the Cterminal interaction with the III-IV linker, which has been suggested as necessary to stabilize the inactivation gate, to minimize sustained channel activity during depolarization, and to prevent cardiac arrhythmias that lead to sudden death. Together, these data offer new biochemical evidence for Ca2+/CaM modulation of Na+ channel function.