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1.
Neurobiol Learn Mem ; 179: 107402, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33581316

RESUMEN

The insular cortex (IC) is notably implicated in emotional and cognitive processing; however, little is known regarding to what extent its two main subregions play functionally distinct roles on memory consolidation of conditioned fear tasks. Here we verified the effects of temporary functional inactivation of the anterior (aIC) and posterior IC (pIC) on contextual and tone fear memory. Rats received post-training bilateral infusions of the GABAA receptor agonist muscimol into either the aIC or pIC and were tested 48 and 72 h after the delay tone fear conditioning session to assess the background contextual (CFC) and tone (TFC) fear conditioning, respectively. Inactivation of the aIC during memory consolidation did not affect fear memory for CFC or TFC. On the other hand, post-training inactivation of the pIC impaired TFC but not CFC. Our findings indicate that the pIC is a necessary part of the neural circuitry related to the consolidation of cued-fear memories.


Asunto(s)
Corteza Cerebral/fisiología , Condicionamiento Clásico/fisiología , Miedo , Consolidación de la Memoria/fisiología , Estimulación Acústica , Animales , Corteza Cerebral/efectos de los fármacos , Condicionamiento Clásico/efectos de los fármacos , Agonistas de Receptores de GABA-A/farmacología , Consolidación de la Memoria/efectos de los fármacos , Muscimol/farmacología , Ratas
2.
J Endocrinol Invest ; 40(12): 1321-1326, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28589380

RESUMEN

BACKGROUND: Persistence is commonly considered a key factor for the successful management of osteoporosis and fragility fractures. Denosumab is the first biologic agent developed for the treatment of osteoporosis with satisfying data regarding the persistence with this therapy. AIM: The purpose of this multicenter observational real practice study was to evaluate the persistence with denosumab treatment in post-menopausal women affected by osteoporosis. MATERIAL/SUBJECTS AND METHODS: Women were recruited in four specialized centers for the management of osteoporosis in North, Center and South of Italy. We included women with a diagnosis of post-menopausal osteoporosis, aged >50 years, able to obtain a prescription according to the Italian reimbursement criteria in force during the study period for anti-osteoporotic pharmacological treatment. They initiated a treatment with subcutaneous denosumab (Prolia®) 60 mg/every 6 months between November 2011 and May 2016. Women who had received aromatase inhibitors were excluded. Patients were assessed at baseline and every 6 months for all treatment length. Persistence data were evaluated for a total of 36 months. RESULTS: Eight hundred seventy women were enrolled; mean aged 70 years, with a mean body mass index of 24.8 ± 4.1 kg/m2. At the Dual-energy X-ray absorptiometry assessment, the mean lumbar spine T-score was -2.76 ± 1.14 standard deviations (SD) and the mean femoral neck T-score was -2.49 ± 0.80 SD. During the study, the total persistence was 91.4%. Total dropouts were 75 (8.6%), higher within the initial 6-month period of treatment. CONCLUSIONS: Persistence to denosumab treatment in our observational real practice study was very high. These results suggest that factors such as frequency of visits, pharmacological schedule, and opportunity to call the doctor might play an important role in the persistence and adherence to treatment to obtain maximum therapeutic effect and avoid further fragility fractures.


Asunto(s)
Conservadores de la Densidad Ósea/uso terapéutico , Densidad Ósea/efectos de los fármacos , Denosumab/uso terapéutico , Cumplimiento de la Medicación/estadística & datos numéricos , Osteoporosis Posmenopáusica/tratamiento farmacológico , Fracturas Osteoporóticas/tratamiento farmacológico , Anciano , Femenino , Estudios de Seguimiento , Humanos , Italia/epidemiología , Persona de Mediana Edad , Osteoporosis Posmenopáusica/epidemiología , Fracturas Osteoporóticas/epidemiología , Pronóstico
3.
J Endocrinol Invest ; 38(3): 367-72, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25352234

RESUMEN

AIM: Several chronic metabolic alterations are present in obese subjects. While it is well known about the detrimental effect of abdominal adipose tissue on chronic metabolic clinical condition, less is known on the role of lean mass in obese subjects. Thus, the aim of our study was to evaluate the potential correlation of muscle mass, metabolic condition and inflammation status in obese individuals. METHODS: The study included 426 obese subjects (86 men and 340 female; mean age 44.8 ± 14 years; BMI: 34.9 ± 6.1 kg/m(2)). Exclusion criteria were chronic medical conditions or use of medications affecting bone metabolism, alterations of hormonal and nutritional status, vitamin D supplementation, recent weight loss and prior bariatric surgery. Patients underwent measurements of bone mineral density (lumbar and hip) and body composition (lean mass, total and trunk fat mass) by dual X-ray absorptiometry and were evaluated for hormonal and metabolic profile and inflammatory markers. RESULTS: Higher lean body mass (LM%) was inversely correlated with homeostasis model assessment of insulin resistance (p < 0.0091; r(2) 0.03938) and associated with lower fibrinogen levels (p < 0.0001; r(2) 0.1263). Interestingly, in obese subjects, LM% was associated with higher levels of vitamin D (p < 0.0001, r(2) 0.1140), osteocalcin (p < 0.0001, r(2) 0.2401) and insulin-like growth factor-1 (IGF-1) (p < 0.0002, r(2) 0.1367). CONCLUSION: Our results show for the first time that in obese patients, higher amounts of lean mass are directly linked to a lower inflammatory profile and to better insulin sensitivity, but also to the presence of higher level of vitamin D and IGF-1. Moreover, these data suggest that higher levels of lean mass in obese people correlate with a better metabolic profile and, thus, strongly suggest the need to develop programs to facilitate an increase in physical activity in obese people.


Asunto(s)
Composición Corporal/fisiología , Inflamación/metabolismo , Resistencia a la Insulina/fisiología , Obesidad/metabolismo , Vitamina D/sangre , Adulto , Femenino , Humanos , Inflamación/sangre , Masculino , Persona de Mediana Edad , Obesidad/sangre
4.
Int J Clin Pract ; 64(6): 817-20, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20518955

RESUMEN

BACKGROUND: Obese individuals often present comorbidities while they appear protected against the development of osteoporosis. However, few and contradictory data are now available on skeletal modifications in obese patients. The aim of this study was to characterise bone mineral density (BMD) in overweight (BMI > 25 < 29.9) and obese (BMI > 30) patients. METHODS: We selected 398 patients (291 women, 107 men, age 44.1 + 14.2 years, BMI 35.8 + 5.9 kg/m(2)) who underwent clinical examination, blood tests and examination of body composition. Subjects with chronic conditions or taking medications interfering with bone metabolism, hormonal and nutritional status and recent weight loss were excluded. RESULTS: Interestingly, 37% (n = 146) of this population showed a significantly lower than expected lumbar BMD: 33% (n = 98) of women showed a T-score -1.84 +/- 0.71, and 45% (n = 48) of men showed a T-score -1.88 +/- 0.64. When the population was divided into subgroups based on different BMI, it was noted that overweight (BMI > 25 < 29.9) was neutral or protective for BMD, whereas obesity (BMI > 30) was associated with a low bone mass, compatible with a diagnosis of osteoporosis. No differences were observed in hormones and lipid profiles among subgroups. CONCLUSIONS: Our results indicate that a subpopulation of obese patients has a significant low lumbar BMD than expected for age. Thus, a careful characterisation of skeletal metabolism might be useful in all obese individuals to avoid fragility fractures later in life.


Asunto(s)
Índice de Masa Corporal , Densidad Ósea/fisiología , Obesidad/fisiopatología , Osteoporosis/fisiopatología , Adulto , Estudios de Cohortes , Femenino , Humanos , Vértebras Lumbares/fisiología , Masculino , Persona de Mediana Edad , Obesidad/complicaciones , Osteoporosis/complicaciones
5.
Nanotechnology ; 20(49): 495304, 2009 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-19904025

RESUMEN

Highly oriented AlN single crystal nanowires with aspect ratio up to 600, diameter in the range of 40-500 nm, and 100 microm lengths, have been synthesized via a vapor-solid growth mechanism. The results were obtained at 1750 degrees C and 850 mbar nitrogen pressure on vicinal SiC substrates pretreated by SiC sublimation epitaxy in order to attain distinguishable terraces. It was found that the nanowires change in thickness after they have reached a critical length, and this fact contributes to an understanding of the growth mechanism of AlN nanowires. The nanowires are hexagonally shaped and perfectly aligned along the [0001] direction with a small tilt given by the substrate vicinality. Under nitrogen excess a preferential growth along the c-axis of the wurtzite structure takes place while below some critical value of nitrogen pressure the growth mode switches to lateral. The AlN nanowires are shown to have a dislocation free wurtzite crystal structure. Some possible applications are discussed.

6.
Neuroscience ; 153(1): 84-94, 2008 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-18367339

RESUMEN

The dorsal striatum (DS) is involved in various forms of learning and memory such as procedural learning, habit learning, reward-association and emotional learning. We have previously reported that bilateral DS lesions disrupt tone fear conditioning (TFC), but not contextual fear conditioning (CFC) [Ferreira TL, Moreira KM, Ikeda DC, Bueno OFA, Oliveira MGM (2003) Effects of dorsal striatum lesions in tone fear conditioning and contextual fear conditioning. Brain Res 987:17-24]. To further elucidate the participation of DS in emotional learning, in the present study, we investigated the effects of bilateral pretest (postraining) electrolytic DS lesions on TFC. Given the well-acknowledged role of the amygdala in emotional learning, we also examined a possible cooperation between DS and the amygdala in TFC, by using asymmetrical electrolytic lesions, consisting of a unilateral lesion of the central amygdaloid nucleus (CeA) combined to a contralateral DS lesion. The results show that pre-test bilateral DS lesions disrupt TFC responses, suggesting that DS plays a role in the expression of TFC. More importantly, rats with asymmetrical pre-training lesions were impaired in TFC, but not in CFC tasks. This result was confirmed with muscimol asymmetrical microinjections in DS and CeA, which reversibly inactivate these structures. On the other hand, similar pretest lesions as well as unilateral electrolytic lesions of CeA and DS in the same hemisphere did not affect TFC. Possible anatomical substrates underlying the observed effects are proposed. Overall, the present results underscore that other routes, aside from the well-established CeA projections to the periaqueductal gray, may contribute to the acquisition/consolidation of the freezing response associated to a TFC task. It is suggested that CeA may presumably influence DS processing via a synaptic relay on dopaminergic neurons of the substantia nigra compacta and retrorubral nucleus. The present observations are also in line with other studies showing that TFC and CFC responses are mediated by different anatomical networks.


Asunto(s)
Amígdala del Cerebelo/fisiología , Condicionamiento Psicológico/fisiología , Cuerpo Estriado/fisiología , Miedo/fisiología , Reacción Cataléptica de Congelación/fisiología , Red Nerviosa/fisiología , Amígdala del Cerebelo/anatomía & histología , Animales , Cuerpo Estriado/anatomía & histología , Desnervación , Estimulación Eléctrica/efectos adversos , Emociones/fisiología , Lateralidad Funcional/fisiología , Agonistas del GABA/farmacología , Masculino , Red Nerviosa/anatomía & histología , Vías Nerviosas/anatomía & histología , Vías Nerviosas/fisiología , Pruebas Neuropsicológicas , Ratas , Ratas Wistar
7.
J Med Genet ; 43(4): 315-25, 2006 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16118345

RESUMEN

BACKGROUND: Osteopetrosis, a genetic disease characterised by osteoclast failure, is classified into three forms: infantile malignant autosomal recessive osteopetrosis (ARO), intermediate autosomal recessive osteopetrosis (IRO), and autosomal dominant osteopetrosis (ADO). METHODS: We studied 49 patients, 21 with ARO, one with IRO, and 27 with type II ADO (ADO II). RESULTS: Most ARO patients bore known or novel (one case) ATP6i (TCIRG1) gene mutations. Six ADO II patients had no mutations in ClCN7, the only so far recognised gene implicated, suggesting involvement of yet unknown genes. Identical ClCN7 mutations produced differing phenotypes with variable degrees of severity. In ADO II, serum tartrate resistant acid phosphatase was always elevated. Bone alkaline phosphatase (BALP) was generally low, but osteocalcin was high, suggesting perturbed osteoblast differentiation or function. In contrast, BALP was high in ARO patients. Elevated osteoclast surface/bone surface was noted in biopsies from most ARO patients. Cases with high osteoclasts also showed increased osteoblast surface/bone surface. ARO osteoclasts were morphologically normal, with unaltered formation rates, intracellular pH handling, and response to acidification. Their resorption activity was greatly reduced, but not abolished. In control osteoclasts, all resorption activity was abolished by combined inhibition of proton pumping and sodium/proton antiport. CONCLUSIONS: These findings provide a rationale for novel therapies targeting pH handling mechanisms in osteoclasts and their microenvironment.


Asunto(s)
Canales de Cloruro/genética , Osteopetrosis/diagnóstico , Osteopetrosis/genética , ATPasas de Translocación de Protón Vacuolares/genética , Adolescente , Adulto , Fosfatasa Alcalina/sangre , Resorción Ósea/metabolismo , Resorción Ósea/patología , Niño , Preescolar , Canales de Cloruro/química , Femenino , Genotipo , Humanos , Concentración de Iones de Hidrógeno , Masculino , Osteocalcina/sangre , Osteoclastos/patología , Osteoclastos/fisiología , Osteopetrosis/terapia , Monoéster Fosfórico Hidrolasas/sangre , Intercambiadores de Sodio-Hidrógeno/fisiología
8.
J Phys Condens Matter ; 28(22): 224005, 2016 06 08.
Artículo en Inglés | MEDLINE | ID: mdl-26952789

RESUMEN

The question of optical bandgap anisotropy in the monoclinic semiconductor ß-Ga2O3 was revisited by combining accurate optical absorption measurements with theoretical analysis, performed using different advanced computation methods. As expected, the bandgap edge of bulk ß-Ga2O3 was found to be a function of light polarization and crystal orientation, with the lowest onset occurring at polarization in the ac crystal plane around 4.5-4.6 eV; polarization along b unambiguously shifts the onset up by 0.2 eV. The theoretical analysis clearly indicates that the shift in the b onset is due to a suppression of the transition matrix elements of the three top valence bands at Γ point.

9.
Psychopharmacology (Berl) ; 150(3): 300-10, 2000 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10923758

RESUMEN

RATIONALE: Mice exhibit antinociception after a single experience in the elevated plus maze (EPM), an animal model of anxiety. OBJECTIVE: This study investigated the mechanisms involved in this form of anxiety-induced antinociception. METHODS: Nociception was evaluated by means of the writhing test in mice confined either to the open or enclosed arms of the EPM. The effects of systemic (naloxone, midazolam and 8-OH-DPAT) or intra-amygdala (8-OH-DPAT, NAN-190 and midazolam) drug infusions were investigated in mice previously treated i.p. with 0.6% acetic acid, an algic stimulus that induces abdominal contortions. The effects of these drugs on conventional measures of anxiety (% entries and % time in open arms) in a standard EPM test were also independently investigated. RESULTS: Open-arm confinement resulted in a high-magnitude antinociception (minimum 85%, maximum 450%) compared with enclosed arm confinement. The opiate antagonist naloxone (1 mg/kg and 10 mg/kg) neither blocked this open arm-induced antinociception (OAIA) nor modified indices of anxiety in EPM. Administration of midazolam (0.5-2 mg/kg, s.c.) increased OAIA and produced antinociception in enclosed confined animals, as well as attenuating anxiety in the EPM. The 5-HT(1A) receptor agonist 8-OH-DPAT (0.05-1 mg/kg, s.c.) had biphasic effects on OAIA, antagonising the response at the lowest dose and intensifying it at the highest dose. In addition, low doses of this agent reduced anxiety in the EPM. Although bilateral injections of 8-OH-DPAT (5.6 nmol/0.4 microl) or NAN-190 (5.6 nmol and 10 nmol/0.4 microl) into the amygdala did not alter OAIA, increased anxiety was observed in the EPM. In contrast, intra-amygdala administration of midazolam (10 nmol and 30 nmol/0.4 microl) blocked both OAIA and anxiety. CONCLUSIONS: These results with systemic and intracerebral drug infusion suggest that 5-HT(1A) receptors localised in the amygdala are not involved in the pain inhibitory processes that are "recruited" during aversive situations. However, activation of these receptors does phasically increase anxiety. Although the intrinsic antinociceptive properties of systemically administered midazolam confounded interpretation of its effects on OAIA, intra-amygdala injections of this compound suggest that benzodiazepine receptors in this brain region modulate both the antinociceptive and behavioural (anxiety) responses to the EPM.


Asunto(s)
8-Hidroxi-2-(di-n-propilamino)tetralin/farmacología , Amígdala del Cerebelo/fisiología , Analgesia/psicología , Ansiolíticos/farmacología , Ansiedad/psicología , Midazolam/farmacología , Agonistas de Receptores de Serotonina/farmacología , 8-Hidroxi-2-(di-n-propilamino)tetralin/administración & dosificación , Animales , Ansiolíticos/administración & dosificación , Masculino , Ratones , Microinyecciones , Midazolam/administración & dosificación , Naloxona/farmacología , Antagonistas de Narcóticos/farmacología , Dimensión del Dolor/efectos de los fármacos , Piperazinas/farmacología , Receptores de Serotonina/efectos de los fármacos , Receptores de Serotonina 5-HT1 , Antagonistas de la Serotonina/farmacología , Agonistas de Receptores de Serotonina/administración & dosificación
11.
Learn Mem ; 7(5): 287-92, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11040260

RESUMEN

The nonselective muscarinic antagonist scopolamine is known to impair the acquisition of some learning tasks such as inhibitory avoidance. There has been recent research into the effects of this drug in contextual fear conditioning and tone fear conditioning paradigms. The purpose of the present study was to assess the role of the selective M1 muscarinic antagonist dicyclomine in these paradigms and in the inhibitory avoidance test. Rats were administered different doses of dicyclomine or saline 30 min before acquisition training. The animals were tested 24 hr later, and it was observed that 16 mg/kg of dicyclomine impaired both contextual fear conditioning and inhibitory avoidance. However, dicyclomine (up to 64 mg/kg) did not affect tone fear conditioning. These results suggest that the selective M1 muscarinic antagonist dicyclomine differentially affects aversively motivated tasks known to be dependent on hippocampal integrity (such as contextual fear conditioning and inhibitory avoidance) but does not affect similar hippocampus-independent tasks.


Asunto(s)
Anticolesterolemiantes/farmacología , Diciclomina/farmacología , Emociones/efectos de los fármacos , Memoria/efectos de los fármacos , Receptores Muscarínicos/efectos de los fármacos , Estimulación Acústica , Animales , Reacción de Prevención/efectos de los fármacos , Conducta Animal/efectos de los fármacos , Condicionamiento Psicológico/efectos de los fármacos , Masculino , Ratas , Ratas Wistar , Tiempo de Reacción/efectos de los fármacos , Receptor Muscarínico M1
12.
J Pharmacol Exp Ther ; 201(2): 444-9, 1977 May.
Artículo en Inglés | MEDLINE | ID: mdl-323463

RESUMEN

Acute pain from biliary colic is a model of pathological pain suitable for pharmacological investigations. It has been found useful for assaying analgesic effect of a narcotic-type agent (pentazocine) and a non-narcotic drug (indoprofen), both given intravenously in a single dose. Differences in pain intensity scores assessed on a five-point scale were taken as measurement of the pain-relieving effect. Distribution-free methods were used to estimate the potency ratio of the tested drugs. The analgesic potency of indoprofen based both on total and peak effect was roughly one-tenth that of pentazocine on a weight-for-weight basis. No adverse reactions were associated with indoprofen and a few were found after pentazocine.


Asunto(s)
Antiinflamatorios no Esteroideos/uso terapéutico , Enfermedades de las Vías Biliares/fisiopatología , Cólico/fisiopatología , Dolor/tratamiento farmacológico , Pentazocina/uso terapéutico , Fenilpropionatos/uso terapéutico , Adulto , Anciano , Ensayos Clínicos como Asunto , Relación Dosis-Respuesta a Droga , Evaluación de Medicamentos , Femenino , Humanos , Indoles/administración & dosificación , Indoles/uso terapéutico , Inyecciones Intravenosas , Masculino , Métodos , Persona de Mediana Edad , Pentazocina/administración & dosificación , Fenilpropionatos/administración & dosificación
13.
Behav Pharmacol ; 14(2): 129-36, 2003 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-12658073

RESUMEN

Behavioral sensitization to drugs of abuse seems to involve learning processes. In mice, ethanol-induced locomotor sensitization is potentiated by repeated pairing of ethanol (EtOH) injections and the testing chamber. The present study aimed to test: (1). the association between the performance in a contextual conditioning task and the development of behavioral sensitization to EtOH in mice; (2). whether EtOH sensitization would be expressed in a different testing environment. Male albino Swiss mice (n=72) were initially submitted to a contextual fear conditioning task. After 2 weeks without manipulation, the animals received daily i.p. injections of 2.2 g/kg EtOH (n=52) or saline (n=20), for 21 days. They were tested weekly for locomotor activity in activity cages. After 1 week of withdrawal, all mice received 2.2 g/kg EtOH and had their locomotor activity recorded in an open-field. According to the locomotor behavior displayed along the 21-day treatment, EtOH-treated mice were classified as sensitized (n=15) or non-sensitized (n=15). When these subgroups and saline-treated mice were compared for the freezing response in the conditioning test, sensitized mice displayed a greater freezing time than non-sensitized mice. When challenged with EtOH in the open-field, none of the EtOH-treated subgroups expressed behavioral sensitization. These results suggest that the development of EtOH sensitization seems to be positively associated with contextual learning, and further confirms that the expression of sensitization is highly dependent on contextual cues.


Asunto(s)
Depresores del Sistema Nervioso Central/farmacología , Condicionamiento Psicológico/efectos de los fármacos , Etanol/farmacología , Animales , Reacción de Prevención/efectos de los fármacos , Conducta Animal , Tolerancia a Medicamentos , Estimulación Eléctrica , Miedo/efectos de los fármacos , Miedo/psicología , Masculino , Ratones , Actividad Motora/efectos de los fármacos
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