Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 40
Filtrar
1.
Ultrasound Obstet Gynecol ; 60(3): 381-389, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35247287

RESUMEN

OBJECTIVE: To evaluate the performance of third-trimester ultrasound for the diagnosis of clinically significant placenta accreta spectrum disorder (PAS) in women with low-lying placenta or placenta previa. METHODS: This was a prospective multicenter study of pregnant women aged ≥ 18 years who were diagnosed with low-lying placenta (< 20 mm from the internal cervical os) or placenta previa (covering the internal cervical os) on ultrasound at ≥ 26 + 0 weeks' gestation, between October 2014 and January 2019. Ultrasound suspicion of PAS was raised in the presence of at least one of these signs on grayscale ultrasound: (1) obliteration of the hypoechogenic space between the uterus and the placenta; (2) interruption of the hyperechogenic interface between the uterine serosa and the bladder wall; (3) abnormal placental lacunae. Histopathological examinations were performed according to a predefined protocol, with pathologists blinded to the ultrasound findings. To assess the ability of ultrasound to detect clinically significant PAS, a composite outcome comprising the need for active management at delivery and histopathological confirmation of PAS was considered the reference standard. PAS was considered to be clinically significant if, in addition to histological confirmation, at least one of these procedures was carried out after delivery: use of hemostatic intrauterine balloon, compressive uterine suture, peripartum hysterectomy, uterine/hypogastric artery ligation or uterine artery embolization. The diagnostic performance of each ultrasound sign for clinically significant PAS was evaluated in all women and in the subgroup who had at least one previous Cesarean section and anterior placenta. Post-test probability was assessed using Fagan nomograms. RESULTS: A total of 568 women underwent transabdominal and transvaginal ultrasound examinations during the study period. Of these, 95 delivered in local hospitals, and placental pathology according to the study protocol was therefore not available. Among the 473 women for whom placental pathology was available, clinically significant PAS was diagnosed in 99 (21%), comprising 36 cases of placenta accreta, 19 of placenta increta and 44 of placenta percreta. The median gestational age at the time of ultrasound assessment was 31.4 (interquartile range, 28.6-34.4) weeks. A normal hypoechogenic space between the uterus and the placenta reduced the post-test probability of clinically significant PAS from 21% to 5% in women with low-lying placenta or placenta previa in the third trimester of pregnancy and from 62% to 9% in the subgroup with previous Cesarean section and anterior placenta. The absence of placental lacunae reduced the post-test probability of clinically significant PAS from 21% to 9% in women with low-lying placenta or placenta previa in the third trimester of pregnancy and from 62% to 36% in the subgroup with previous Cesarean section and anterior placenta. When abnormal placental lacunae were seen on ultrasound, the post-test probability of clinically significant PAS increased from 21% to 59% in the whole cohort and from 62% to 78% in the subgroup with previous Cesarean section and anterior placenta. An interrupted hyperechogenic interface between the uterine serosa and bladder wall increased the post-test probability for clinically significant PAS from 21% to 85% in women with low-lying placenta or placenta previa and from 62% to 88% in the subgroup with previous Cesarean section and anterior placenta. When all three sonographic markers were present, the post-test probability for clinically significant PAS increased from 21% to 89% in the whole cohort and from 62% to 92% in the subgroup with previous Cesarean section and anterior placenta. CONCLUSIONS: Grayscale ultrasound has good diagnostic performance to identify pregnancies at low risk of PAS in a high-risk population of women with low-lying placenta or placenta previa. Ultrasound may be safely used to guide management decisions and concentrate resources on patients with higher risk of clinically significant PAS. © 2022 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.


Asunto(s)
Placenta Accreta , Placenta Previa , Cesárea , Femenino , Humanos , Placenta/diagnóstico por imagen , Placenta/patología , Placenta Accreta/diagnóstico por imagen , Placenta Accreta/patología , Placenta Previa/diagnóstico por imagen , Placenta Previa/patología , Embarazo , Tercer Trimestre del Embarazo , Diagnóstico Prenatal , Estudios Prospectivos , Estudios Retrospectivos , Ultrasonografía Prenatal/métodos
2.
Eur Rev Med Pharmacol Sci ; 25(6): 2785-2794, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33829463

RESUMEN

OBJECTIVE: To develop a deep learning-based decision tree for the primary care setting, to stratify adult patients with confirmed and unconfirmed coronavirus disease 2019 (COVID-19), and to predict the need for hospitalization or home monitoring. PATIENTS AND METHODS: We performed a retrospective cohort study on data from patients admitted to a COVID hospital in Rome, Italy, between 5 March 2020 and 5 June 2020. A confirmed case was defined as a patient with a positive nasopharyngeal RT-PCR test result, while an unconfirmed case had negative results on repeated swabs. Patients' medical history and clinical, laboratory and radiological findings were collected, and the dataset was used to train a predictive model for COVID-19 severity. RESULTS: Data of 198 patients were included in the study. Twenty-eight (14.14%) had mild disease, 62 (31.31%) had moderate disease, 64 (32.32%) had severe disease, and 44 (22.22%) had critical disease. The G2 value assessed the contribution of each collected value to decision tree building. On this basis, SpO2 (%) with a cut point at 92 was chosen for the optimal first split. Therefore, the decision tree was built using values maximizing G2 and LogWorth. After the tree was built, the correspondence between inputs and outcomes was validated. CONCLUSIONS: We developed a machine learning-based tool that is easy to understand and apply. It provides good discrimination in stratifying confirmed and unconfirmed COVID-19 patients with different prognoses in every context. Our tool might allow general practitioners visiting patients at home to decide whether the patient needs to be hospitalized.


Asunto(s)
Algoritmos , COVID-19/diagnóstico , COVID-19/terapia , Árboles de Decisión , Servicios de Atención de Salud a Domicilio/estadística & datos numéricos , Hospitalización/estadística & datos numéricos , Anciano , COVID-19/epidemiología , COVID-19/virología , Prueba de COVID-19 , Estudios de Cohortes , Toma de Decisiones Asistida por Computador , Femenino , Estudios de Seguimiento , Humanos , Italia/epidemiología , Aprendizaje Automático , Masculino , Monitoreo Fisiológico , Pronóstico , Estudios Retrospectivos , SARS-CoV-2/aislamiento & purificación
3.
Ultrasound Obstet Gynecol ; 52(2): 258-264, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29532529

RESUMEN

OBJECTIVE: To ascertain the diagnostic accuracy of ultrasound in detecting abnormally invasive placenta (AIP) during the first trimester of pregnancy (11-14 weeks' gestation) in women at risk for this condition. METHODS: This was a retrospective analysis of data collected prospectively from women at risk for AIP based upon the presence of at least one prior Cesarean section (CS) and/or uterine surgery and placenta previa, who had ultrasound assessment for AIP at the time of the 11-14-week scan. The ultrasound signs explored in the present study were: loss of the clear zone, placental lacunae, bladder wall interruption and uterovesical hypervascularity. The potential of ultrasound and different ultrasound signs to predict the different types of AIP was assessed by computing summary estimates of sensitivity, specificity, diagnostic odds ratio (DOR) and positive (LR+) and negative (LR-) likelihood ratios. RESULTS: One hundred and eighty-eight women with placenta previa and at least one previous CS or uterine surgery were included in the study. All the explored ultrasound signs were associated significantly with the occurrence of AIP. Overall, when at least one ultrasound sign was used to make the diagnosis, ultrasound had a sensitivity of 84.3% (95% CI, 74.7-91.4%), specificity of 61.9% (95% CI, 51.9-71.2%), DOR of 8.6 (95% CI, 4.1-19.3), LR+ of 2.2 (95% CI, 1.7-2.9) and LR- of 0.3 (95% CI, 0.1-0.4) in detecting AIP. Using two ultrasound signs to label a case as positive increased the diagnostic accuracy in terms of specificity, although it did not affect sensitivity. Among the different ultrasound signs, loss of the clear zone had a sensitivity of 84.3% (95% CI, 74.7-91.4%) and a specificity of 81.9% (95% CI, 73.2-88.7%) in detecting AIP, while sensitivities for placental lacunae and bladder wall interruption were 78.3% (95% CI, 67.9-86.6%) and 75.9% (95% CI, 65.3-84.6%), respectively, and specificities were 81.0% (95% CI, 72.1-88.0%) and 99.1% (95% CI, 94.8-100.0%), respectively. The optimal combination of sensitivity and specificity was achieved when at least two imaging signs of AIP were used in the diagnostic algorithm. CONCLUSIONS: AIP can be detected from the first trimester of pregnancy in women at risk for this condition, and ultrasound performed between 11 and 14 weeks' gestation has an overall good diagnostic accuracy for detecting all types of AIP. However, these findings are applicable only to women with placenta previa and prior uterine scar. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.


Asunto(s)
Placenta Accreta/diagnóstico por imagen , Placenta Previa/diagnóstico por imagen , Placenta/diagnóstico por imagen , Primer Trimestre del Embarazo , Ultrasonografía Prenatal , Adulto , Femenino , Humanos , Placenta/patología , Placenta Accreta/patología , Placenta Previa/patología , Valor Predictivo de las Pruebas , Embarazo , Reproducibilidad de los Resultados , Estudios Retrospectivos , Medición de Riesgo , Sensibilidad y Especificidad
4.
Ultrasound Obstet Gynecol ; 51(2): 184-188, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-28233462

RESUMEN

OBJECTIVE: Ultrasound assessment of the relationship between the ectopic gestational sac and the endometrial line (cross-over sign; COS) in Cesarean scar pregnancy (CSP) has been shown to be useful in predicting the evolution of CSP towards different types of abnormally invasive placenta (AIP). The aim of this study was to ascertain whether the COS can be used to predict surgical outcome in women with AIP. METHODS: A retrospective analysis was performed of early first-trimester (6-8 weeks' gestation) ultrasound images of women with AIP managed in the third trimester of pregnancy. We hypothesized that assessment of COS may identify cases of AIP at higher risk of intra- or postsurgical morbidity. Outcomes explored were estimated blood loss during surgery, need for and amount of packed red blood cells and fresh frozen plasma units required either during or after surgery, operative time, intrasurgical complications, gestational age at birth, delivery < 34 weeks of gestation, length of hospital stay and admission to intensive care unit. Differences in the explored outcomes were assessed among women with different types of COS variant (COS-1, COS-2+ or COS-2-) as observed on first-trimester ultrasound examination. RESULTS: Sixty-eight pregnancies were included in the study. Mean estimated blood loss was higher in AIP pregnancies with COS-1 than in those with COS-2+ (P = 0.039) or COS-2- (P = 0.01). Mean number of packed red blood cell units required during or after the operation was higher in women with COS-1 compared with those with COS-2+ (P = 0.001) and COS-2- (P = 0.029), while there was no difference between pregnancies with COS-2+ and those with COS-2- (P = 0.797). Mean operative time was longer in AIP pregnancies with COS-1 than in those with COS-2+ (P = 0.039) or COS-2- (P = 0.017). Finally, pregnancies with COS-1 were delivered earlier than those with COS-2+ (P = 0.0001) or COS-2- (P = 0.0001). CONCLUSION: First-trimester ultrasound assessment of the relationship between the ectopic gestational sac and the endometrial line (COS) may identify women with AIP who are at higher risk of intra- or postsurgical morbidity. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.


Asunto(s)
Cesárea/efectos adversos , Cicatriz/diagnóstico por imagen , Placenta Accreta/diagnóstico por imagen , Placenta/diagnóstico por imagen , Primer Trimestre del Embarazo , Embarazo Ectópico/diagnóstico por imagen , Ultrasonografía Prenatal , Adulto , Cicatriz/complicaciones , Cicatriz/etiología , Femenino , Humanos , Placenta/patología , Placenta Accreta/patología , Valor Predictivo de las Pruebas , Embarazo , Embarazo Ectópico/patología , Estudios Retrospectivos
5.
Ultrasound Obstet Gynecol ; 51(2): 176-183, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-28833750

RESUMEN

OBJECTIVES: The primary aim of this systematic review was to ascertain whether ultrasound signs suggestive of abnormally invasive placenta (AIP) are present in the first trimester of pregnancy. Secondary aims were to ascertain the strength of association and the predictive accuracy of such signs in detecting AIP in the first trimester. METHODS: An electronic search of MEDLINE, EMBASE, CINAHL and Cochrane databases (2000-2016) was performed. Only studies reporting on first-trimester diagnosis of AIP that was subsequently confirmed in the third trimester either during operative delivery or by pathological examination were included. Meta-analysis of proportions, random-effects meta-analysis and hierarchical summary receiver-operating characteristics curve analysis were used to analyze the data. RESULTS: Seven studies, involving 551 pregnancies at high risk of AIP, were included. At least one ultrasound sign suggestive of AIP was detected in 91.4% (95% CI, 85.8-95.7%) of cases with confirmed AIP. The most common ultrasound feature in the first trimester of pregnancy was low implantation of the gestational sac close to a previous uterine scar, which was observed in 82.4% (95% CI, 46.6-99.8%) of cases. Anechoic spaces within the placental mass (lacunae) were observed in 46.0% (95% CI, 10.9-83.7%) and a reduced myometrial thickness in 66.8% (95% CI, 45.2-85.2%) of cases affected by AIP. Pregnancies with a low implantation of the gestational sac had a significantly higher risk of AIP (odds ratio, 19.6 (95% CI, 6.7-57.3)), with a sensitivity and specificity of 44.4% (95% CI, 21.5-69.2%) and 93.4% (95% CI, 90.5-95.7%), respectively. CONCLUSIONS: Ultrasound signs of AIP can be present during the first trimester of pregnancy, even before 11 weeks' gestation. Low anterior implantation of the placenta/gestational sac close to or within the scar was the most commonly seen early ultrasound sign suggestive of AIP, although its individual predictive accuracy was not high. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.


Asunto(s)
Miometrio/diagnóstico por imagen , Placenta Accreta/diagnóstico por imagen , Placenta/diagnóstico por imagen , Ultrasonografía Prenatal/métodos , Femenino , Humanos , Miometrio/irrigación sanguínea , Placenta/patología , Embarazo , Primer Trimestre del Embarazo , Sensibilidad y Especificidad
6.
Res Dev Disabil ; 38: 97-107, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25575283

RESUMEN

This study was aimed at evaluating the spatial abilities in individuals with Prader-Willi syndrome (PWS) by using an ecological large-scale task with multiple rewards. To evaluate the extent of spatial deficit in PWS individuals, we compare their performances with those of individuals with Williams Syndrome (WS) in which the spatial deficits have been widely described. Participants had to explore an open space to search nine rewards placed in buckets arranged according to three spatial configurations: a Cross, a 3×3 Matrix and a Cluster composed by three groups of three buckets each. PWS individuals exhibited an explorative deficit in Cluster and Cross configurations, while WS participants in Matrix and Cross configurations. The findings indicate that the structural affordances of the environment influence the explorative strategies and can be related to how spatial information is processed.


Asunto(s)
Conducta Exploratoria , Síndrome de Prader-Willi/psicología , Percepción Espacial/fisiología , Memoria Espacial/fisiología , Adolescente , Estudios de Casos y Controles , Niño , Cognición , Femenino , Humanos , Masculino , Pruebas Neuropsicológicas , Síndrome de Prader-Willi/fisiopatología , Desempeño Psicomotor , Análisis y Desempeño de Tareas , Síndrome de Williams/fisiopatología , Síndrome de Williams/psicología , Adulto Joven
7.
Psychol Med ; 45(5): 897-910, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25126858

RESUMEN

BACKGROUND: Individuals with autism spectrum disorders (ASDs) are characterized by social communication difficulties and behavioural rigidity. Difficulties in learning from others are one of the most devastating features of this group of conditions. Nevertheless, the nature of learning difficulties in ASDs is still unclear. Given the relevance of implicit learning for social and communicative functioning, a link has been hypothesized between ASDs and implicit learning deficit. However, studies that have employed formal testing of implicit learning in ASDs provided mixed results. METHOD: We undertook a systematic search of studies that examined implicit learning in ASDs using serial reaction time (SRT), alternating serial reaction time (ASRT), pursuit rotor (PR), and contextual cueing (CC) tasks, and synthesized the data using meta-analysis. A total of 11 studies were identified, representing data from 407 individuals with ASDs and typically developing comparison participants. RESULTS: The results indicate that individuals with ASDs do not differ in any task considered [SRT and ASRT task: standardized mean difference (SMD) -0.18, 95% confidence interval (CI) -0.71 to 0.36; PR task: SMD -0.34, 95% CI -1.04 to 0.36; CC task: SMD 0.27, 95% CI -0.07 to 0.60]. CONCLUSIONS: Based on our synthesis of the existing literature, we conclude that individuals with ASDs can learn implicitly, supporting the hypothesis that implicit learning deficits do not represent a core feature in ASDs.


Asunto(s)
Trastorno del Espectro Autista/psicología , Discapacidades para el Aprendizaje/psicología , Aprendizaje/fisiología , Trastorno del Espectro Autista/fisiopatología , Señales (Psicología) , Humanos , Discapacidades para el Aprendizaje/fisiopatología , Pruebas Neuropsicológicas , Tiempo de Reacción , Aprendizaje Seriado
8.
Psychol Med ; 44(11): 2437-47, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24433947

RESUMEN

BACKGROUND: Observing another person performing a complex action accelerates the observer's acquisition of the same action and limits the time-consuming process of learning by trial and error. Learning by observation requires specific skills such as attending, imitating and understanding contingencies. Individuals with autism spectrum disorder (ASD) exhibit deficits in these skills. METHOD: The performance of 20 ASD children was compared with that of a group of typically developing (TD) children matched for chronological age (CA), IQ and gender on tasks of learning of a visuomotor sequence by observation or by trial and error. Acquiring the correct sequence involved three phases: a detection phase (DP), in which participants discovered the correct sequence and learned how to perform the task; an exercise phase (EP), in which they reproduced the sequence until performance was error free; and an automatization phase (AP), in which by repeating the error-free sequence they became accurate and speedy. RESULTS: In the DP, ASD children were impaired in detecting a sequence by trial and error only when the task was proposed as first, whereas they were as efficient as TD children in detecting a sequence by observation. In the EP, ASD children were as efficient as TD children. In the AP, ASD children were impaired in automatizing the sequence. Although the positive effect of learning by observation was evident, ASD children made a high number of imitative errors, indicating marked tendencies to hyperimitate. CONCLUSIONS: These findings demonstrate the imitative abilities of ASD children although the presence of imitative errors indicates an impairment in the control of imitative behaviours.


Asunto(s)
Trastorno del Espectro Autista/fisiopatología , Conducta Imitativa/fisiología , Aprendizaje/fisiología , Desempeño Psicomotor/fisiología , Niño , Femenino , Humanos , Masculino
9.
Meat Sci ; 89(2): 238-42, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21570777

RESUMEN

Forty male Italian Merino lambs were used to study the effects of four feeding systems on muscle fatty acids composition: S group-ten lambs were kept indoors, and fed with concentrate for all experimental period (89 days); P group-ten lambs were allowed to graze a pasture for all experimental period; PS37 group-ten lambs were allowed to graze a pasture for 52 days and shifted indoor, fed with concentrate, 37 days before slaughtered; PS14 group, where 10 lambs were fed on pasture for 75 days and shifted indoor, fed with concentrate, 14 days before slaughtered. Grazing lowered the levels of C12:0, C14:0, C16:0 and n-6 PUFA and increased n-3 PUFA and CLA isomer compared to concentrate feeding. After a short period of indoor finishing with concentrate, the fatty acid characteristics of the meat retain a part of the benefits occurring from grazing, while a longer period seems to erase almost all the benefits from grazing.


Asunto(s)
Alimentación Animal , Ácidos Grasos Omega-3/análisis , Ácidos Linoleicos Conjugados/análisis , Músculo Esquelético/química , Oveja Doméstica/crecimiento & desarrollo , Crianza de Animales Domésticos/métodos , Animales , Masculino , Carne
10.
Res Dev Disabil ; 32(3): 972-85, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21353462

RESUMEN

This study aimed to evaluate spatial function in subjects with Williams syndrome (WS) by using a large-scale task with multiple rewards and comparing the spatial abilities of WS subjects with those of mental age-matched control children. In the present spatial task, WS participants had to explore an open space to search nine rewards placed in buckets arranged according to three spatial configurations: a cross, a 3 × 3 matrix and a cluster composed by three groups of three buckets each. The findings demonstrate that WS individuals were impaired in efficiently exploring the environment and in building cognitive spatial maps. In exploring the three spatial configurations, they performed worse than control subjects on all parameters analyzed. In fact, WS individuals took more time to complete the task, made more errors, performed a reduced number of error-free trials, displayed lower search efficiency, exhibited shorter spatial spans, showed a higher number of no-visits and displayed marked tendencies to perseverate and to neglect some buckets. Furthermore, WS individuals showed disorganized explorative patterns in comparison to control children. WS influenced performances differentially as a specific effect of the susceptibility of the configurations to being explored in a principled way. In the cross configuration that had strong spatial constraints, both groups exhibited their worst performances. In the matrix configuration, the altered explorative strategies of the WS subjects primarily affected their central exploration. The performances in the cluster configuration indicated that chunking was a strategy of strength in both TD and WS groups. In conclusion, WS individuals' deficits exhibited in the present explorative test may be considered an index of their difficulties in spatial orientation and motion perception displayed in the real world. The marked impairment in spatial information processing is discussed in neuro-anatomical alterations reported in WS.


Asunto(s)
Conducta Exploratoria/fisiología , Juegos Experimentales , Recompensa , Percepción Espacial/fisiología , Síndrome de Williams/fisiopatología , Cognición/fisiología , Femenino , Humanos , Masculino , Motivación/fisiología , Pruebas Neuropsicológicas , Desempeño Psicomotor/fisiología , Adulto Joven
11.
Meat Sci ; 87(3): 229-33, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21071156

RESUMEN

Thirty male Merinizzata italiana lambs were divided into three groups after weaning according to live weight. The diet of the three groups differed in the main protein source used in the concentrate, soybean meal for treatment SBM, faba bean for treatment FB and peas for treatment PEA. Lambs were fed ad libitum and slaughtered at about 160 days of age. Meat from the PEA group had higher proportions of the essential fatty acids C18:2 ω-6 and C18:3 ω-3 than from FB and SBM lambs and consequently its derivatives, C20:4 ω-6 and C20:5 ω-3 respectively, were higher in meat from PEA animals, compared to SBM and FB ones. The total n-3 fatty acids were highest in meat from PEA lambs and consequently PEA lambs showed a more favourable n-6/n-3 ratio. In conclusion the use of legume seeds such as peas in lamb diets positively affected intramuscular fatty acid composition.


Asunto(s)
Alimentación Animal/análisis , Ácidos Grasos/análisis , Músculo Esquelético/química , Proteínas de Vegetales Comestibles/administración & dosificación , Animales , Ácidos Grasos Esenciales/análisis , Ácidos Grasos Omega-3/análisis , Ácidos Grasos Omega-6/análisis , Masculino , Carne/análisis , Valor Nutritivo , Pisum sativum/química , Control de Calidad , Semillas/química , Oveja Doméstica , Glycine max/química , Vicia faba/química , Destete , Aumento de Peso
12.
J Neurosci Res ; 88(3): 478-86, 2010 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-19746422

RESUMEN

Because the sequencing property is one of the functions in which cerebellar circuits are involved, it is important to analyze the features of sequential learning in the presence of cerebellar damage. Hemicerebellectomized and control rats were tested in a four-choice visuomotor learning task that required both the detection of a specific sequence of correct choices and the acquisition of procedural rules about how to perform the task. The findings indicate that the presence of the hemicerebellectomy did not affect the first phases of detection and acquisition of the sequential visuomotor task, delayed but did not prevent the learning of the sequential task, slowed down speed-up and proceduralization phases, and loosened the reward-response associative structure. The performances of hemicerebellectomized animals in the serial learning task as well as in the open field task demonstrated that the delayed sequential learning task could not be ascribed to impairment of motor functions or discriminative abilities or to low levels of motivation. The delay in sequential learning observed in the presence of a cerebellar lesion appeared to be related mainly to a delay of the automatization of the response. In conclusion, it may be advanced that, through cortical and subcortical connections, the cerebellum provides the acquisition of rapid and accurate sensory-guided sequence of responses.


Asunto(s)
Cerebelo/fisiología , Aprendizaje/fisiología , Desempeño Psicomotor/fisiología , Análisis de Varianza , Animales , Ansiedad/fisiopatología , Cerebelo/cirugía , Conducta Exploratoria/fisiología , Masculino , Actividad Motora/fisiología , Pruebas Neuropsicológicas , Distribución Aleatoria , Ratas , Ratas Wistar , Recompensa , Factores de Tiempo , Percepción Visual/fisiología
13.
Int J Dev Neurosci ; 27(3): 205-13, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19429385

RESUMEN

This study was aimed at evaluating spatial function in subjects with Williams syndrome by using the radial arm maze task and comparing their spatial abilities with those of mental age-matched control subjects. Two different paradigms were administered: the free-choice version for analyzing the aspects linked mainly to procedural and mnesic components, the forced-choice version for disentangling components linked to spatial working memory from the procedural ones. The findings evidenced a deficit in the acquisition of procedural competences as well as in the spatial memory processes in Williams subjects. In the free-choice paradigm, they performed worse than control subjects on all parameters analyzed. Namely, they needed more time to complete the task, did not collect all rewards, exhibited low values of the spatial span as well as low percentages of correct visits, and displayed a reduced use of the most efficient exploration strategies. Even in the forced-choice paradigm, Williams subjects made a number of errors significantly higher than control subjects. The marked impairment in spatial information processing is discussed on the light of neuro-anatomical alterations reported in Williams subjects.


Asunto(s)
Aprendizaje por Laberinto/fisiología , Desempeño Psicomotor/fisiología , Percepción Espacial/fisiología , Conducta Espacial/fisiología , Síndrome de Williams/fisiopatología , Adolescente , Niño , Femenino , Humanos , Masculino , Memoria/fisiología , Pruebas Neuropsicológicas , Síndrome de Williams/patología , Adulto Joven
14.
Neurobiol Learn Mem ; 92(3): 310-7, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19362159

RESUMEN

The aim of the present study was to investigate whether the cerebellar structures are involved in functions requiring cognitive flexibility abilities. The flexibility of the hemicerebellectomized and control animals in learning a four-choice learning task, adapting to ever-changing response rules was investigated. While in the initial phase of the task both experimental groups exhibited similar performances, only the control animals significantly improved their performance as the sessions went by. The lack of improvement in lesioned animals' performance rendered their responses particularly defective in the final phases of the task, when conversely intact animals performed best, exploiting their "learning to learn" ability. The findings demonstrate the defective influence of the cerebellar lesion on the acquisition, not the execution, of new responses. The results underline the crucial role of the cerebellum in mediating cognitive flexibility behaviors.


Asunto(s)
Adaptación Psicológica/fisiología , Cerebelo/fisiología , Cognición/fisiología , Aprendizaje/fisiología , Análisis de Varianza , Animales , Emociones/fisiología , Lateralidad Funcional , Masculino , Procesos Mentales/fisiología , Actividad Motora/fisiología , Pruebas Neuropsicológicas , Distribución Aleatoria , Ratas , Ratas Wistar , Factores de Tiempo
15.
Travel Med Infect Dis ; 6(4): 240-4, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18571116

RESUMEN

Mycobacterium fortuitum, as well as Mycobacterium marinum and Mycobacterium chelonae, are the etiological agents of fish Mycobacterioses. Mycobacteriosis has been reported to affect a wide range of freshwater and marine fish species, suggesting an ubiquitous distribution, and can cause zoonotic infections (known as "fish tank granuloma" or "swimming pool granuloma") in humans exposed to fish and contaminated water. Infection in human consists of nodular cutaneous lesions that can progress to tenosynovitis, arthritis, and osteomyelitis, depending on the immunological status. Authors describe some cases observed during routinary diagnostic activity in aquarium fish. Fish were sampled and histopathological, microbiological, and biomolecular exams were carried out. Histopathology showed systemic granulomatosis. Microbiological and biomolecular exams allowed us to identify the M. fortuitum as a main species. Finally, some considerations on the legal aspects of such disease are discussed.


Asunto(s)
Acuicultura/legislación & jurisprudencia , Enfermedades de los Peces/diagnóstico , Granuloma/veterinaria , Infecciones por Mycobacterium no Tuberculosas/veterinaria , Mycobacterium fortuitum/aislamiento & purificación , Zoonosis/microbiología , Animales , Secuencia de Bases , Unión Europea , Enfermedades de los Peces/microbiología , Enfermedades de los Peces/patología , Carpa Dorada/microbiología , Granuloma/diagnóstico , Granuloma/microbiología , Granuloma/patología , Humanos , Datos de Secuencia Molecular , Infecciones por Mycobacterium no Tuberculosas/diagnóstico , Infecciones por Mycobacterium no Tuberculosas/microbiología , Infecciones por Mycobacterium no Tuberculosas/patología , Mycobacterium fortuitum/clasificación , Mycobacterium fortuitum/genética , Pez Cebra/microbiología
16.
Neuroscience ; 154(2): 444-53, 2008 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-18472349

RESUMEN

The aim of the present study was to investigate whether basal forebrain lesions were able to impair a task requiring cognitive flexibility abilities and analyzing the effect of the rearing in an enriched environment on such form of flexibility in rats with or without basal forebrain cholinergic lesions. In adult rats reared in enriched or standard conditions of the cholinergic projection to the neocortex damage was inflicted by 192 IgG-saporin injection into Ch4 region of basal forebrain. Their performance was compared with those of intact animals reared in analogous conditions in a four-choice serial learning task which taps flexibility in adapting to changing response rules. The results underlined the crucial role of the basal forebrain in mediating cognitive flexibility behaviors and revealed that the increase in social interactions, cognitive stimulation and physical activity of the rearing in enriched environment attenuated impairments caused by the cholinergic lesion. These findings demonstrate that rearing in an enriched environment can improve the ability to cope with brain damage suffered in adulthood.


Asunto(s)
Conducta de Elección/fisiología , Cognición/fisiología , Ambiente , Prosencéfalo/fisiología , Animales , Anticuerpos Monoclonales/toxicidad , Química Encefálica/efectos de los fármacos , Conducta de Elección/efectos de los fármacos , Colina O-Acetiltransferasa/metabolismo , Cognición/efectos de los fármacos , Inmunotoxinas/toxicidad , Masculino , Actividad Motora/efectos de los fármacos , Actividad Motora/fisiología , Plasticidad Neuronal/efectos de los fármacos , Plasticidad Neuronal/fisiología , Prosencéfalo/efectos de los fármacos , Prosencéfalo/metabolismo , Desempeño Psicomotor/efectos de los fármacos , Desempeño Psicomotor/fisiología , Ratas , Ratas Wistar , Esquema de Refuerzo , Proteínas Inactivadoras de Ribosomas Tipo 1/toxicidad , Saporinas , Aprendizaje Seriado/efectos de los fármacos , Aprendizaje Seriado/fisiología , Conducta Social
17.
Meat Sci ; 76(3): 390-4, 2007 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22060979

RESUMEN

The main objective of this study was to evaluate the effects of ewe dietary treatments on the intramuscular fatty acid composition of suckling lambs. Twenty-four pregnant Italian Merino ewes were divided into two equal groups. One group (pasture-fed group) was allowed to graze a natural pasture and the other group (stall-fed group) was penned indoors and fed with hay and concentrate. After lambing, all ewes stayed with their respective lambs for the whole experimental period. Lambs were slaughtered at 100 days of age with an average live weight of 20kg. Fatty acid profiles of milk and lamb meat (longissimus lumborum muscle) were analysed. Intramuscular fat from pasture-fed lambs showed higher (P<0.001) proportions of polyunsaturated fatty acids. The percentage of lauric (C12:0; P<0.05), palmitic (C16.0; P<0.001) and oleic (C18.1; P<0.001) fatty acids were higher in the intramuscular fat from stall-fed lambs, whereas pasture-fed lambs showed greater proportions of linolenic (C18:3; P<0.001), eicosapentaenoic (C20:5; P<0.001) and docosapentaenoic (C22:5; P<0.05) fatty acids. Moreover, the intramuscular fat from pasture-fed lambs displayed a higher (P<0.001) PUFA/SFA ratio, and a lower (p<0.001) n-6/n-3 ratio. The conjugated linoleic acid (CLA) tended to be higher (P=0.07) in the intramuscular fat from pasture-fed lambs. This study confirmed that pasture enhanced the unsaturated fatty acid profile of intramuscular fat in lambs including n-3 fatty acids.

18.
Acta Crystallogr C ; 57(Pt 4): 493-4, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11313606

RESUMEN

The crystal structure of the title compound, C(17)H(10)O(3), is the first example of a furocoumarin containing three fused rings. The tricyclic furocoumarin fragment is perfectly planar. The phenyl substituent forms a dihedral angle of 39.52 (8) degrees with the plane of the tricyclic system. The crystal packing involves centrosymmetric dimers interconnected by strong pi-interactions between their furo[3,2-c]coumarin fragments [at distances of 3.42 (4) A].

19.
Small Rumin Res ; 40(1): 51-56, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11259875

RESUMEN

Twenty "Merinizzata Italiana" lambs were introduced to two experimental diets. Ten animals (five males and five females, control group) received the traditional diet that is supplied by farmers in southern Italy, which comprised of oat hay ad libitum and commercial concentrate. The second group (the same number of lambs, silage group) received citrus pulp and wheat straw silage ad libitum and 70% of the commercial concentrate supplied to the control group. The animals were slaughtered after 80 days of feeding and carcass and some meat quality parameters were measured. No differences were observed for live weight between treatments, and carcass weights were similar for the two diets, but with obvious differences between sexes. Animals on silage produced carcasses with a better muscular conformation and with a lower fatness score (P<0.05). Subcutaneous fat colour was influenced by sex, being lighter in the female carcasses (P<0.05). Dissection of different anatomical parts showed a higher percentage of lean and a lower proportion of fat in silage samples compared to control ones. Ultimate pH was highly affected by sex being higher in the samples from male lambs (P<0.01), but was unaffected by diet treatment. Diet tended to affect meat shear force value which was lower in the silage samples, although, samples from all the animals were extremely tender. Meat from silage samples had a higher water content (P<0.05). Overall, in our experimental conditions, the use of citrus pulp silage seemed to be economically convenient for producing animals with substantially unmodified carcass and meat quality characteristics.

20.
Neurosci Lett ; 300(3): 176-8, 2001 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-11226639

RESUMEN

Melatonin affects the circadian sleep/wake cycle, but it is not clear whether it may influence drug-induced narcosis. Sodium thiopenthal was administered intraperitoneally into male rats pre-treated with melatonin (0.05, 0.5, 5 and 50 mg/kg). Melatonin pre-treatment affected in a dual manner barbiturate narcosis, however, no dose-effect correlation was found. In particular, low doses reduced the latency to and prolonged the duration of barbiturate narcosis. In contrast, the highest dose of melatonin (50 mg/kg) caused a paradoxical increase in the latency and produced a sustained reduction of the duration of narcosis, and a reduction in mortality rate. Melatonin 0.5 and 5 mg/kg influenced the duration but not the latency of ketamine- or diazepam-induced narcosis. Thus, the dual action of melatonin on pharmacological narcosis seems to be specific for the barbiturate mechanism of action.


Asunto(s)
Antioxidantes/farmacología , Melatonina/farmacología , Sueño/efectos de los fármacos , Inconsciencia/tratamiento farmacológico , Adyuvantes Anestésicos/farmacología , Anestésicos Disociativos/farmacología , Animales , Antioxidantes/administración & dosificación , Barbitúricos , Diazepam/farmacología , Relación Dosis-Respuesta a Droga , Ketamina/farmacología , Masculino , Melatonina/administración & dosificación , Ratas , Ratas Wistar , Sueño/fisiología , Inconsciencia/inducido químicamente , Inconsciencia/mortalidad
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...