In an attempt to evaluate whether previous training antagonizes age-related memory deficits, aged... more In an attempt to evaluate whether previous training antagonizes age-related memory deficits, aged rats with previous training experience were compared with aged and young naive rats in the Morris water maze test. The findings of our study indicate that experience seems to facilitate the preservation of the spatial reference memory for 12 months in the aged rat, whereas senescent naive animals showed the usual age-related memory deficits. However, experience seems task-specific since the same aged rats fail to acquire a new different task.
A series of triazolopyridine derivatives (compounds 2a-l) were synthesized in order to explore th... more A series of triazolopyridine derivatives (compounds 2a-l) were synthesized in order to explore the effect of modifications of the alkylpiperazine moiety of trazodone (fragment A) on binding affinity for 5HT2A and alpha1 receptors. All of the synthesized compounds show a decrease of affinity for both 5HT2A and alpha1 receptors, as compared to trazodone, with the exception of compounds 2b,c which bear a methyl group in an alpha position to the aliphatic nitrogen atom N1. These compounds showed a decrease of affinity only for the alpha1 receptor. The stereochemical influence of the piperazine moiety of compound 2c was also evaluated. Enantiomer (S)-2c showed the most significant differences between 5HT2A and alpha1 receptor affinity (IC50 values) and among the corresponding functional properties (pA2 values). Since (S)-2c cannot generate the metabolite 4-(3-chlorophenyl)piperazine this product was selected for further pharmacological studies.
A nationwide survey has been undertaken to evaluate the resources and the activities of Italian h... more A nationwide survey has been undertaken to evaluate the resources and the activities of Italian hospital neurology units (NU) in the emergency setting. NU are widely disseminated throughout the entire country and 220 (84%) are located in hospitals with an emergency room (ER). Complete data about hospital setting, structural and functional characteristics of each NU and clinical activities were obtained from 159 (72.3%). Each NU has, on average, 25 beds (7% bedside monitoring), 7 neurologists and 17 nurses. A neuroscience department is present in 25% of the hospitals. The ER is the source of 71% of the 148,040 annual admissions and of 57% of the 577,279 annual neurological consultations. Stroke is the most common cause of admission (29%), followed by epilepsy/headache and transient ischaemic attacks. Head trauma prevails in hospitals with no neurosurgical units. Cerebrovascular disorders are the main cause of neurological consultations (28%), followed by headache (22%), dizziness (13%), head trauma (13%), impairment of consciousness (12%) and epilepsy (9%). Only 36% of NU have a 24-h/day, 7 days/week on-duty neurologist and 28% have a stroke unit. The burden of neurological activities is unrelated to the geographical area and hospital’s complexity (size, structural and functional context, ER organisation, presence of stroke units, neurosurgery units or 24/7 neurological service).
Background Hereditary hemorrhagic telangiectasia is a genetic disease characterized by teleangiec... more Background Hereditary hemorrhagic telangiectasia is a genetic disease characterized by teleangiectasias involving virtually every organ. There are limited data in the literature regarding the natural history of liver vascular malformations in hemorrhagic telangiectasia and their associated morbidity and mortality. Aim This prospective cohort study sought to assess the outcome of liver involvement in hereditary hemorrhagic telangiectasia patients. Methods We analyzed 16 years of surveillance data from a tertiary hereditary hemorrhagic telangiectasia referral center in Italy. We considered for inclusion in this study 502 consecutive Italian patients at risk of hereditary hemorrhagic telangiectasia who presented at the hereditary hemorrhagic telangiectasia referral center and underwent a multidisciplinary screening protocol for the diagnosis of hereditary hemorrhagic telangiectasia. Of the 502 individuals assessed in the center, 154 had hepatic vascular malformations and were the subject of the study; 198 patients with hereditary hemorrhagic telangiectasia and without hepatic vascular malformations were the controls. Additionally, we report the response to treatment of patients with complicated hepatic vascular malformations. Results The 154 patients were included and followed for a median period of 44 months (range 12–181); of these, eight (5.2%) died from VM-related complications and 39 (25.3%) experienced complications. The average incidence rates of death and complications were 1.1 and 3.6 per 100 person-years, respectively. The median overall survival and event-free survival after diagnosis were 175 and 90 months, respectively. The rate of complete response to therapy was 63%. Conclusions This study shows that substantial morbidity and mortality are associated with liver vascular malformations in hereditary hemorrhagic telangiectasia patients.
Objective To evaluate the inter- and intrareader variability for interpretation of a modified Lar... more Objective To evaluate the inter- and intrareader variability for interpretation of a modified Larsen's radiographic classification system for juvenile rheumatoid arthritis (JRA) focused on osteochondral lesions and a conventional Larsen's classification system, compared to a reference MR scoring system of corresponding images. Materials and methods Seventy-five radiographs of 60 children with JRA, performed within a short interval of time from the MR examinations, were independently evaluated by three experienced radiologists, three diagnostic imaging residents and three rheumatologists, in two separate sessions, according to the two different classification methods, blinded to the corresponding MR images. Results The inter- and intrareader concordance rates between the two radiographic classification systems and the MR-related radiographs were respectively poor and poor/moderate. The interobserver range of weighted kappa values for the conventional and the modified Larsen's system respectively was 0.25–0.37 vs 0.19–0.39 for radiologists, 0.25–0.37 vs 0.18–0.30 for residents and 0.19–0.51 vs 0.17–0.29 for rheumatologists. The intrareader rate ranged from 0.17–0.55 for radiologists, 0.2–0.56 for residents, and 0.14–0.59 for rheumatologists. Conclusion Although the proposal of a new radiographic classification system for JRA focused on osteochondral abnormalities sounds promising, the low inter- and intrareader concordance rates with an MR-related radiographic system makes the clinical applicability of such a radiographic system less suitable.
A ventilação mecânica é uma terapia importante, mas pode resultar em complicações. Uma das mais r... more A ventilação mecânica é uma terapia importante, mas pode resultar em complicações. Uma das mais relevantes é a lesão pulmonar induzida por ventilador. Devido à hiperdistensão alveolar, o pulmão inicia um processo inflamatório, com infiltrado neutrofílico, formação de membrana hialina, fibrogênese e prejuízo de troca gasosa. Nesse processo, a mecanotransdução da hiperdistensão celular é mediada através do citoesqueleto da célula e de suas interações com a matriz extracelular e com as células vizinhas, de modo que o estímulo mecânico da ventilação se traduz em sinalização bioquímica intracelular, desencadeando ativação endotelial, permeabilidade vascular pulmonar, quimiotaxia leucocitária, produção de citocinas e, possivelmente, lesão de órgãos à distância. Estudos clínicos demonstram essa relação entre distensão pulmonar e mortalidade em pacientes com lesão pulmonar induzida por ventilador. Entretanto, apesar de o citoesqueleto ter um papel fundamental na patogênese da lesão pulmonar induzida por ventilador, a literatura carece de estudos utilizando modelos in vivo sobre as alterações do citoesqueleto e de suas proteínas associadas durante esse processo patológico.
ALGERI, S., L. BIAGINI, A. MANFRIDI AND N. PITSIKAS. Age-related ability of rats kept on a life-l... more ALGERI, S., L. BIAGINI, A. MANFRIDI AND N. PITSIKAS. Age-related ability of rats kept on a life-long hypoealoric diet in a spatial memory test. Longitudinal observations. NEUROBIOL AGING 12(4) 277-282, 1991.--Cognitive behavior was assessed in a test specific for spatial memory, according to a longitudinal experimental model, in populations of 12-, 24-and 30-month-old rats which were fed ad lib either a standard (ST) or a hypocaloric (HY) diet, that had been shown to reduce age-related pathologies and to increase survival. Already at 12 months of age, some cognitive deficits were observed in ST but not in HY rats. When retested 12 and 18 months later, the animals performed better at the beginning of the test than when tested for the first time, indicating that some aspects of previous experience lead to a preservation of spatial memory. Deficits which had been previously observed in 2-year-old groups in a cross-sectional experimental model were not evident this time. Some of the differences between the two diet groups observed 12 months before disappeared. When testing was repeated for the third time at 30 months of age, ST fed rats presented very marked deficits in learning and in memory, which were not seen in the HY group. It thus appears that a dietary regimen in which part of the calorie-rich components, such as lipids and carbohydrates, are replaced with vegetable fibers, retards some of the age-related deteriorations of brain functions.
In an attempt to evaluate whether previous training antagonizes age-related memory deficits, aged... more In an attempt to evaluate whether previous training antagonizes age-related memory deficits, aged rats with previous training experience were compared with aged and young naive rats in the Morris water maze test. The findings of our study indicate that experience seems to facilitate the preservation of the spatial reference memory for 12 months in the aged rat, whereas senescent naive animals showed the usual age-related memory deficits. However, experience seems task-specific since the same aged rats fail to acquire a new different task.
A series of triazolopyridine derivatives (compounds 2a-l) were synthesized in order to explore th... more A series of triazolopyridine derivatives (compounds 2a-l) were synthesized in order to explore the effect of modifications of the alkylpiperazine moiety of trazodone (fragment A) on binding affinity for 5HT2A and alpha1 receptors. All of the synthesized compounds show a decrease of affinity for both 5HT2A and alpha1 receptors, as compared to trazodone, with the exception of compounds 2b,c which bear a methyl group in an alpha position to the aliphatic nitrogen atom N1. These compounds showed a decrease of affinity only for the alpha1 receptor. The stereochemical influence of the piperazine moiety of compound 2c was also evaluated. Enantiomer (S)-2c showed the most significant differences between 5HT2A and alpha1 receptor affinity (IC50 values) and among the corresponding functional properties (pA2 values). Since (S)-2c cannot generate the metabolite 4-(3-chlorophenyl)piperazine this product was selected for further pharmacological studies.
A nationwide survey has been undertaken to evaluate the resources and the activities of Italian h... more A nationwide survey has been undertaken to evaluate the resources and the activities of Italian hospital neurology units (NU) in the emergency setting. NU are widely disseminated throughout the entire country and 220 (84%) are located in hospitals with an emergency room (ER). Complete data about hospital setting, structural and functional characteristics of each NU and clinical activities were obtained from 159 (72.3%). Each NU has, on average, 25 beds (7% bedside monitoring), 7 neurologists and 17 nurses. A neuroscience department is present in 25% of the hospitals. The ER is the source of 71% of the 148,040 annual admissions and of 57% of the 577,279 annual neurological consultations. Stroke is the most common cause of admission (29%), followed by epilepsy/headache and transient ischaemic attacks. Head trauma prevails in hospitals with no neurosurgical units. Cerebrovascular disorders are the main cause of neurological consultations (28%), followed by headache (22%), dizziness (13%), head trauma (13%), impairment of consciousness (12%) and epilepsy (9%). Only 36% of NU have a 24-h/day, 7 days/week on-duty neurologist and 28% have a stroke unit. The burden of neurological activities is unrelated to the geographical area and hospital’s complexity (size, structural and functional context, ER organisation, presence of stroke units, neurosurgery units or 24/7 neurological service).
Background Hereditary hemorrhagic telangiectasia is a genetic disease characterized by teleangiec... more Background Hereditary hemorrhagic telangiectasia is a genetic disease characterized by teleangiectasias involving virtually every organ. There are limited data in the literature regarding the natural history of liver vascular malformations in hemorrhagic telangiectasia and their associated morbidity and mortality. Aim This prospective cohort study sought to assess the outcome of liver involvement in hereditary hemorrhagic telangiectasia patients. Methods We analyzed 16 years of surveillance data from a tertiary hereditary hemorrhagic telangiectasia referral center in Italy. We considered for inclusion in this study 502 consecutive Italian patients at risk of hereditary hemorrhagic telangiectasia who presented at the hereditary hemorrhagic telangiectasia referral center and underwent a multidisciplinary screening protocol for the diagnosis of hereditary hemorrhagic telangiectasia. Of the 502 individuals assessed in the center, 154 had hepatic vascular malformations and were the subject of the study; 198 patients with hereditary hemorrhagic telangiectasia and without hepatic vascular malformations were the controls. Additionally, we report the response to treatment of patients with complicated hepatic vascular malformations. Results The 154 patients were included and followed for a median period of 44 months (range 12–181); of these, eight (5.2%) died from VM-related complications and 39 (25.3%) experienced complications. The average incidence rates of death and complications were 1.1 and 3.6 per 100 person-years, respectively. The median overall survival and event-free survival after diagnosis were 175 and 90 months, respectively. The rate of complete response to therapy was 63%. Conclusions This study shows that substantial morbidity and mortality are associated with liver vascular malformations in hereditary hemorrhagic telangiectasia patients.
Objective To evaluate the inter- and intrareader variability for interpretation of a modified Lar... more Objective To evaluate the inter- and intrareader variability for interpretation of a modified Larsen's radiographic classification system for juvenile rheumatoid arthritis (JRA) focused on osteochondral lesions and a conventional Larsen's classification system, compared to a reference MR scoring system of corresponding images. Materials and methods Seventy-five radiographs of 60 children with JRA, performed within a short interval of time from the MR examinations, were independently evaluated by three experienced radiologists, three diagnostic imaging residents and three rheumatologists, in two separate sessions, according to the two different classification methods, blinded to the corresponding MR images. Results The inter- and intrareader concordance rates between the two radiographic classification systems and the MR-related radiographs were respectively poor and poor/moderate. The interobserver range of weighted kappa values for the conventional and the modified Larsen's system respectively was 0.25–0.37 vs 0.19–0.39 for radiologists, 0.25–0.37 vs 0.18–0.30 for residents and 0.19–0.51 vs 0.17–0.29 for rheumatologists. The intrareader rate ranged from 0.17–0.55 for radiologists, 0.2–0.56 for residents, and 0.14–0.59 for rheumatologists. Conclusion Although the proposal of a new radiographic classification system for JRA focused on osteochondral abnormalities sounds promising, the low inter- and intrareader concordance rates with an MR-related radiographic system makes the clinical applicability of such a radiographic system less suitable.
A ventilação mecânica é uma terapia importante, mas pode resultar em complicações. Uma das mais r... more A ventilação mecânica é uma terapia importante, mas pode resultar em complicações. Uma das mais relevantes é a lesão pulmonar induzida por ventilador. Devido à hiperdistensão alveolar, o pulmão inicia um processo inflamatório, com infiltrado neutrofílico, formação de membrana hialina, fibrogênese e prejuízo de troca gasosa. Nesse processo, a mecanotransdução da hiperdistensão celular é mediada através do citoesqueleto da célula e de suas interações com a matriz extracelular e com as células vizinhas, de modo que o estímulo mecânico da ventilação se traduz em sinalização bioquímica intracelular, desencadeando ativação endotelial, permeabilidade vascular pulmonar, quimiotaxia leucocitária, produção de citocinas e, possivelmente, lesão de órgãos à distância. Estudos clínicos demonstram essa relação entre distensão pulmonar e mortalidade em pacientes com lesão pulmonar induzida por ventilador. Entretanto, apesar de o citoesqueleto ter um papel fundamental na patogênese da lesão pulmonar induzida por ventilador, a literatura carece de estudos utilizando modelos in vivo sobre as alterações do citoesqueleto e de suas proteínas associadas durante esse processo patológico.
ALGERI, S., L. BIAGINI, A. MANFRIDI AND N. PITSIKAS. Age-related ability of rats kept on a life-l... more ALGERI, S., L. BIAGINI, A. MANFRIDI AND N. PITSIKAS. Age-related ability of rats kept on a life-long hypoealoric diet in a spatial memory test. Longitudinal observations. NEUROBIOL AGING 12(4) 277-282, 1991.--Cognitive behavior was assessed in a test specific for spatial memory, according to a longitudinal experimental model, in populations of 12-, 24-and 30-month-old rats which were fed ad lib either a standard (ST) or a hypocaloric (HY) diet, that had been shown to reduce age-related pathologies and to increase survival. Already at 12 months of age, some cognitive deficits were observed in ST but not in HY rats. When retested 12 and 18 months later, the animals performed better at the beginning of the test than when tested for the first time, indicating that some aspects of previous experience lead to a preservation of spatial memory. Deficits which had been previously observed in 2-year-old groups in a cross-sectional experimental model were not evident this time. Some of the differences between the two diet groups observed 12 months before disappeared. When testing was repeated for the third time at 30 months of age, ST fed rats presented very marked deficits in learning and in memory, which were not seen in the HY group. It thus appears that a dietary regimen in which part of the calorie-rich components, such as lipids and carbohydrates, are replaced with vegetable fibers, retards some of the age-related deteriorations of brain functions.
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