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1.
J Clin Pharm Ther ; 42(6): 733-737, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28597476

RESUMO

WHAT IS KNOWN AND OBJECTIVE: Bacterial infections are the leading causes of morbidity and mortality in haematologic patients with chemotherapy-induced neutropenia. The only strategy shown to be effective in reducing febrile neutropenia incidence is fluoroquinolone prophylaxis, but the safety of this class of drugs in patients with glucose-6-phosphate dehydrogenase deficiency (G6PD-), the most common human enzyme defect, is still controversial because of the claimed association with acute haemolytic anaemia. METHODS: We retrospectively analysed 242 patients treated with 628 intensive chemotherapy courses. Of these, 59 patients were with G6PD-. All patients underwent fluoroquinolone prophylaxis and were transfused according to our single-unit transfusion policy. The principal endpoint was the incidence of acute haemolytic anaemia. Secondary endpoints included the incidence of febrile neutropenia, microbiologically and clinically documented infection (MDI and CDI) and the incidence of Gram-positive or Gram-negative infections. RESULTS AND DISCUSSIONS: No episode of acute haemolytic anaemia was observed in the entire cohort. The incidence of MDI and CDI was similar, but the incidence of invasive fungal disease (IFD; P<.0001, HR 11.4, 95%CI 3.5-37.05) and Candida sepsis (P=.008, HR 37, 95%CI 2.01-680.9) was higher in patients with G6PD-. Interestingly, we observed a reduced incidence of febrile neutropenia in patients with G6PD- (P=.01, HR 0.46, 95%CI 0.25-0.8). WHAT IS NEW AND CONCLUSIONS: Our data suggest that fluoroquinolone prophylaxis in patients with G6PD-, treated with intensive chemotherapy, is feasible and safe. Our findings on the incidence of IFD and febrile neutropenia suggest that G6PD may be important in susceptibility to opportunistic pathogens and host response in neutropenic patients.


Assuntos
Antibacterianos/uso terapêutico , Infecções Bacterianas/tratamento farmacológico , Fluoroquinolonas/uso terapêutico , Deficiência de Glucosefosfato Desidrogenase/microbiologia , Neoplasias/microbiologia , Neutropenia/microbiologia , Adolescente , Adulto , Idoso , Antibioticoprofilaxia/métodos , Antineoplásicos/efeitos adversos , Antineoplásicos/uso terapêutico , Bacteriemia/tratamento farmacológico , Feminino , Deficiência de Glucosefosfato Desidrogenase/induzido quimicamente , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/tratamento farmacológico , Neutropenia/induzido quimicamente , Estudos Retrospectivos , Adulto Jovem
2.
Clin Nutr ; 36(3): 775-781, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-27312085

RESUMO

BACKGROUND & AIMS: Ghrelin is a gastric orexigenic hormone whose activating acylation plays a relevant role in the regulation of energy balance. Nutritional modulators of ghrelin acylation and plasma acylated ghrelin (AG) concentration remain however largely undefined. We aimed at investigating whether circulating free fatty acids (FFA) contribute to regulate plasma AG and its ratio (AG/TG) to total hormone (TG). METHODS: Plasma FFA, TG, AG and AG/TG were measured in a primary outpatient care setting in a community-based population cohort of 850 individuals (age 54 ± 10 years, M/F: 408/442) from the North-East Italy MoMa study. 150-min intravenous lipid infusions in rodents (10% lipids, 600 µl/h) were used to investigate the potential causal role of FFA in the regulation of plasma ghrelin profile. RESULTS: Plasma FFA were associated positively with AG and AG/TG while negatively with TG (P < 0.01). Associations between FFA, AG and AG/TG remained statistically significant (P < 0.02) in multiple regression analysis including HOMA insulin resistance and metabolic confounders, and both AG and AG/TG but not TG increased through plasma FFA quartiles (P < 0.01). Consistent with these findings, intravenous lipid infusion with plasma FFA elevation caused elevations of AG and AG/TG (P < 0.05) with no TG modifications. CONCLUSIONS: The current findings demonstrate a novel role for circulating FFA availability to up-regulate plasma AG, which could involve FFA-induced stimulation of ghrelin acylation.


Assuntos
Emulsões Gordurosas Intravenosas/administração & dosagem , Ácidos Graxos não Esterificados/sangue , Grelina/sangue , Acilação , Adulto , Animais , Antropometria , Glicemia/metabolismo , Índice de Massa Corporal , HDL-Colesterol/sangue , Estudos de Coortes , Modelos Animais de Doenças , Ácidos Graxos Ômega-3/administração & dosagem , Humanos , Infusões Intravenosas , Insulina/sangue , Itália , Masculino , Pessoa de Meia-Idade , Ratos , Ratos Wistar , Triglicerídeos/sangue
3.
Clin Nutr ; 35(5): 1168-73, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-26508327

RESUMO

BACKGROUND & AIMS: Ghrelin is a gastric hormone circulating in acylated (AG) and unacylated (UG) forms, and higher plasma total ghrelin (TG) and UG may be cross-sectionally associated with lower insulin resistance in metabolic syndrome patients. The potential value of ghrelin forms in predicting insulin resistance and its time-related changes in community-based population cohorts remains unknown. METHODS: We measured TG, AG and calculated UG (TG-AG) in 716 individuals from the North-East-Italy MoMa study (age: 55 ± 9 years, BMI: 29 ± 5 kg/m(2), M/F:349/367) to test the hypothesis that circulating TG and UG, but not AG are negatively associated with insulin resistance (HOMA). We further hypothesized that baseline TG and UG negatively predict 5-year HOMA changes in a 350-individual subgroup. RESULTS: Baseline TG and UG were associated negatively with HOMA after adjusting for gender and body mass index (BMI). Baseline gender- and BMI-adjusted TG and UG were also negatively associated with HOMA at 5-year follow-up (n = 350), and changes in TG and UG were negatively associated with changes in HOMA (P < 0.05) after adjustment for anthropometric and metabolic confounders. No statistically significant correlations were observed between AG and baseline or 5-year HOMA. CONCLUSIONS: In a North-East Italy community-based population cohort, plasma TG and UG but not AG are negatively associated with HOMA. TG and UG and their changes also independently predict 5-year HOMA changes. TG and UG are therefore novel potential modulators of insulin resistance and may contribute to predict its time-related changes in humans.


Assuntos
Grelina/sangue , Resistência à Insulina , Síndrome Metabólica/sangue , Acilação , Adulto , Idoso , Biomarcadores/sangue , Glicemia/metabolismo , Índice de Massa Corporal , Proteína C-Reativa/metabolismo , Colesterol/sangue , Estudos de Coortes , Estudos Transversais , Feminino , Seguimentos , Humanos , Insulina/sangue , Itália/epidemiologia , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Adulto Jovem
4.
Parasitol Res ; 114(8): 3137-43, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25968992

RESUMO

The aim of this study was to investigate the epidemiology and transmission of Taenia hydatigena in sheep and dogs from Sardinia and the economic estimation of losses due to this metacestodosis in lambs. A total of 7781 Sarda breed lambs were examined at abattoirs for the detection of Cysticercus tenuicollis or necrotic-haemorrhagic tracks of their migration. Morphological and molecular identification of parasites was carried out. Individual faecal samples from 300 dogs were examined for copromicroscopic investigations and coproELISA assay. An overall prevalence of 14.6% for T. hydatigena cysticercosis was found in the examined lambs. In total, 10,807 parasitary tracks were found, with an abundance of 1.39 and an average intensity of 9.52. The molecular analysis of the isolates showed an overall pairwise nucleotide divergence for the CO1 and ND1 was of 0-3.1 and 0-3.3%, respectively. Low intra- and interspecific variation was recorded for C. tenuicollis isolates used in this study which suggested the absence of differentiation. Microscopic examination of dog faeces showed a total prevalence of 31.3% for endoparasites in the examined samples (94/300). Taeniid eggs were found in 8.3% of the dogs. The results of the monoclonal antibody ATH4 ELISA test showed a prevalence of 11% (33/300) for T. hydatigena coproantigens. The total economic costs related to cysticercosis amounted to almost € 330,000. The prevalence of C. tenuicollis in 14.6% of 30-40-day-old lambs highlights the high parasitic pressure by T. hydatigena in the territory of Sardinia, Italy.


Assuntos
Cisticercose/veterinária , Doenças dos Ovinos/parasitologia , Taenia , Animais , Cisticercose/economia , Cisticercose/epidemiologia , Cisticercose/parasitologia , Doenças do Cão/epidemiologia , Doenças do Cão/parasitologia , Cães , Ensaio de Imunoadsorção Enzimática , Fezes/parasitologia , Itália/epidemiologia , Prevalência , Ovinos , Doenças dos Ovinos/economia , Doenças dos Ovinos/epidemiologia
5.
Vet Parasitol ; 203(1-2): 59-64, 2014 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-24704343

RESUMO

An ultrasound-based survey for cystic echinococcosis (CE) in sheep was carried out in Sardinia in 2012. The study was done on three farms (A, B, C) which had been pre-selected for different CE prevalence levels (A: >80%, B: 50-80%, C: <50%). In total, 129 sheep were examined on the farms using portable ultrasound equipment (A: n=51, B: n=30, C: n=48). Within a period of 20 days after ultrasound examination, all sheep were slaughtered and underwent a parasitological post-mortem examination for cysts in the liver and lungs. With post-mortem as gold standard, ultrasonography gave a test sensitivity of 88.7% and a specificity of 75.9%, while the positive and negative predictive values were 81.8% and 84.6%, respectively. When only sheep with fertile cysts were considered, the sensitivity of the test increased to 100%. We conclude that the ultrasound examination of the liver in sheep - using state-of-the-art technology - is a sensitive and specific diagnostic tool, which is cost-effective, highly appropriate for field use and requires only moderate time (no shaving required). The method can also be applied to other livestock species and will be useful tool in epidemiological studies, monitoring schemes and vaccination/control trials.


Assuntos
Equinococose Hepática/veterinária , Doenças dos Ovinos/diagnóstico por imagem , Ultrassonografia/veterinária , Animais , Equinococose Hepática/diagnóstico por imagem , Itália , Fígado/diagnóstico por imagem , Fígado/parasitologia , Pulmão/diagnóstico por imagem , Pulmão/parasitologia , Valor Preditivo dos Testes , Sensibilidade e Especificidade , Ovinos , Doenças dos Ovinos/parasitologia , Ultrassonografia/normas
6.
Parasitol Res ; 112(5): 2079-82, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23274489

RESUMO

Coenurosis is a central nervous system disease of wild and domestic ruminants caused by Coenurus cerebralis, a bladder worm stage of Taenia multiceps). Even in Sardinia island, this metacestode seems to be widespread in sheep (Scala et al. Vet Parasitol 143(3-4):294-298, 2007) where coenurosis is an important health problem (Varcasia et al. Parasitol Res 99(5):622-626, 2006) the last and unique report of coenurosis in cattle was in 1990 (Cubeddu et al. 1990). In the present paper, a case of bovine coenurosis in Sardinia was described 22 years after the first report with a morphological a biomolecular characterization. A 2-year-old Limousine bull was euthanized in the Bolotana (NU) municipality (Central Sardinia). The remote anamnesis achieved from the farmer reporting that the bull showed neurological symptoms from 1 year of age previously classified as nutritional problems by the farm's veterinary. The breeder also says that the bull have by self-produced the skull fracture by hitting a gaff in the farm. The skull was opened and the brain removed and carefully examined showing two coenurus cysts containing clear fluid with numerous scoleces both in the right hemisphere. Morphological features of the cysts and mt-DNA sequencing confirm that the parasites were T. multiceps Coenuri.


Assuntos
Doenças do Sistema Nervoso Central/veterinária , Taenia/genética , Taenia/ultraestrutura , Teníase/veterinária , Animais , Autopsia , Bovinos , Doenças dos Bovinos/diagnóstico , Doenças dos Bovinos/parasitologia , Doenças dos Bovinos/patologia , Doenças do Sistema Nervoso Central/diagnóstico , Doenças do Sistema Nervoso Central/parasitologia , Doenças do Sistema Nervoso Central/patologia , Itália , Masculino , Crânio/parasitologia , Crânio/patologia , Taenia/classificação , Teníase/diagnóstico , Teníase/parasitologia , Teníase/patologia
7.
Phys Rev Lett ; 105(23): 237203, 2010 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-21231500

RESUMO

The electronic ferroelectric lutetium ferrite (LuFe(2)O(4)) was studied by x-ray diffraction as a function of pressure. Pressure is shown to induce an irreversible rhombohedral to orthorhombic transition leading to a supercell determined by the combination of electron and synchrotron x-ray diffraction. This new configuration is proposed to be charge ordered in agreement with the results of resistivity measurements.

8.
Dentomaxillofac Radiol ; 35(4): 236-43, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16798918

RESUMO

OBJECTIVES: It is important to recognize osteonecrosis of the jaws in patients treated with bisphosphonates because an early diagnosis can make a significant difference to the outcome of the disease. The aim of this study is to describe the radiological features of bisphosphonate osteonecrosis (BON) in order to aid its prompt recognition. METHODS: A conventional radiograph, a computed tomograph (CT), a magnetic resonance image (MRI) and a 99Tc(m)-MDP 3-phase bone scan were carried out for 11 patients with BON. The main imaging findings of osteonecrosis are described. RESULTS: Conventional radiography and CT displayed osteolytic lesions with the involvement of cortical bone. MRI demonstrated the characteristic features of osteonecrosis and the oedema of soft tissues. Both CT and MRI were very useful in defining the extent of the lesions. 99Tc(m)-MDP three-phase bone scan was the most sensitive tool to detect the osteonecrosis at an early stage. CONCLUSIONS: 99Tc(m)-MDP three-phase bone scans who could be used as a screening test to detect subclinical osteonecrosis in patients who have received bisphosphonates. CT scans and MRI are useful in defining the features and extent of osteolytic lesions.


Assuntos
Conservadores da Densidade Óssea/efeitos adversos , Difosfonatos/efeitos adversos , Doenças Maxilomandibulares/diagnóstico por imagem , Osteonecrose/diagnóstico por imagem , Idoso , Idoso de 80 Anos ou mais , Neoplasias Ósseas/tratamento farmacológico , Neoplasias Ósseas/secundário , Feminino , Humanos , Imidazóis/efeitos adversos , Doenças Maxilomandibulares/induzido quimicamente , Doenças Maxilomandibulares/patologia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/tratamento farmacológico , Osteonecrose/induzido quimicamente , Osteonecrose/patologia , Radiografia Panorâmica , Cintilografia , Estudos Retrospectivos , Medronato de Tecnécio Tc 99m , Tomografia Computadorizada por Raios X , Ácido Zoledrônico
9.
Neuroscience ; 140(3): 759-67, 2006 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-16580145

RESUMO

This experiment assessed the effect of neonatal ventral hippocampus lesions in rats, a heuristic approach to model schizophrenia, on continuous delayed alternation and conditional discrimination learning performance before and after complete cerebral maturation. Delays (0, 5, 15, and 30 s) were introduced in the tasks to help dissociate between a hippocampal and a prefrontal cortex dysfunction. At postnatal day (PND) 6 or 7, rats received bilateral microinjections of ibotenic acid or phosphate-buffered saline in the ventral hippocampus. From PND 26 to PND 35, rats were tested on the alternation task in a T-maze; from PND 47 to PND 85, the same rats were tested in the discrimination task where a stimulus and a response location had to be paired. Deficits in ventral hippocampus-lesioned rats were observed in both tasks whether a delay was introduced before a response or not. Impaired performance regardless of delay length, combined with high rates of perseverative errors, suggested a post-lesional prefrontal cortex dysfunction which persisted from the juvenile stage into adulthood. Premature cognitive impairments could not be predicted on the basis of the neurodevelopmental animal model of schizophrenia. Nevertheless, they appear consistent with accounts of premorbidly compromised memory, both immediate and delayed, in subgroups of schizophrenia patients.


Assuntos
Transtornos Cognitivos/fisiopatologia , Hipocampo/fisiopatologia , Transtornos da Memória/fisiopatologia , Córtex Pré-Frontal/fisiopatologia , Esquizofrenia/fisiopatologia , Psicologia do Esquizofrênico , Envelhecimento/fisiologia , Animais , Animais Recém-Nascidos , Aprendizagem da Esquiva/efeitos dos fármacos , Aprendizagem da Esquiva/fisiologia , Transtornos Cognitivos/etiologia , Denervação , Modelos Animais de Doenças , Feminino , Hipocampo/crescimento & desenvolvimento , Hipocampo/patologia , Ácido Ibotênico/efeitos adversos , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Aprendizagem em Labirinto/fisiologia , Transtornos da Memória/etiologia , Vias Neurais/crescimento & desenvolvimento , Vias Neurais/patologia , Vias Neurais/fisiopatologia , Neurotoxinas/efeitos adversos , Córtex Pré-Frontal/crescimento & desenvolvimento , Ratos , Ratos Sprague-Dawley , Esquizofrenia/complicações
10.
Eur J Dermatol ; 15(4): 271-3, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16048757

RESUMO

The real risk of lymphoproliferative disease in psoriatic patients has not yet been defined. Two explanations can be given for the occurrence of these malignancies: the broad immune activation typical of psoriasis and the administration of an immuno-suppressive treatment. A few studies describing the development of non Hodgkin lymphomas in psoriatic patients undergoing cyclosporine A have been published, but data about the occurrence of chronic lymphoproliferative disorders have never been reported. Here we describe the occurrence of hairy cell leukemia and Waldenstrom macroglobulinemia in two psoriatic patients treated with cyclosporine A. It remains unclear in our cases of chronic lymphoproliferative disease, as well as in the reported cases of psoriatic patients who develop lymphomas, whether psoriasis or the immunosuppressive treatment could play a role, although it is not possible to exclude a synergism between these factors.


Assuntos
Ciclosporina/uso terapêutico , Imunossupressores/uso terapêutico , Leucemia de Células Pilosas/diagnóstico , Psoríase/tratamento farmacológico , Macroglobulinemia de Waldenstrom/diagnóstico , Adulto , Ciclosporina/administração & dosagem , Ciclosporina/efeitos adversos , Diagnóstico Diferencial , Esquema de Medicação , Feminino , Humanos , Imunossupressores/administração & dosagem , Imunossupressores/efeitos adversos , Leucemia de Células Pilosas/complicações , Psoríase/complicações , Macroglobulinemia de Waldenstrom/complicações
12.
Eur J Haematol ; 73(3): 219-22, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15287921

RESUMO

Several cases of spontaneous remission (SR) interrupting the invariably progressive course of untreated acute myeloblastic leukemia (AML) have been reported so far. We shall add to this series the hematological and cytogenetic SR occurring in a 72-yr-old man affected by AML following myelodysplastic syndrome. At diagnosis cytogenetic analysis showed the 48, xy, del (6) (p22-pter), +13, +14 karyotype. Owing to a lobar pneumonia, the chemotherapy was deferred and a broad spectrum antibiotic therapy was established. Supportive care included red cells and platelet transfusions and low-dose corticosteroid. Two months later, after the pneumonia had completely disappeared, a complete remission, lasting about 5 months, was documented on bone marrow morphological and cytogenetical examination, although some degree of myeloid dysplasia persisted. Possible mechanisms of the various SRs described during the course of AML are discussed with a review of the literature.


Assuntos
Leucemia Mieloide Aguda/patologia , Corticosteroides/uso terapêutico , Idoso , Antibacterianos/uso terapêutico , Transfusão de Componentes Sanguíneos , Análise Citogenética , Testes Hematológicos , Humanos , Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/terapia , Masculino , Síndromes Mielodisplásicas/diagnóstico , Síndromes Mielodisplásicas/patologia , Pneumonia Pneumocócica/tratamento farmacológico , Remissão Espontânea
13.
Neurotoxicol Teratol ; 25(3): 335-47, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12757830

RESUMO

Pregnant C57BL/6 mice were chronically treated with 0, 4, 6, or 8 ppm of methylmercury chloride (MeHg) in drinking water during fetal and early postnatal development. Four behavioral functions were analyzed in female and male offspring between the age of 6 and 12 weeks: motor coordination learning on the rotarod; training to spatial alternation in the standard T maze followed by a working memory test with delays; spontaneous locomotion and rearings in the open field; reference and working memory assessment in the modified T maze [Behav. Neurosci. 102 (1988) 635]. Chronic perinatal treatment with MeHg resulted in moderate brain levels of mercury near birth which rapidly decreased during nursing. MeHg exerted an effect on the performance of females, but not of males, on two of the four measurements. All treated females exhibited less locomotion than control mice when the open field was new, but not in the following four sessions when the environment was becoming increasingly familiar. Working memory was impaired in females treated with 6 and 8 ppm of MeHg in the modified T maze, but not on the test with delays in the standard T maze. Taken together, these results show that chronic exposure to MeHg during fetal and postnatal development had sex-dependent effects on horizontal exploration and on working memory in the modified T maze, and no effects on motor coordination learning and reference memory.


Assuntos
Comportamento Animal/efeitos dos fármacos , Intoxicação do Sistema Nervoso por Mercúrio/fisiopatologia , Compostos de Metilmercúrio/administração & dosagem , Complicações na Gravidez , Efeitos Tardios da Exposição Pré-Natal , Animais , Comportamento Animal/fisiologia , Encéfalo/metabolismo , Feminino , Fígado/metabolismo , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Aprendizagem em Labirinto/fisiologia , Intoxicação do Sistema Nervoso por Mercúrio/complicações , Intoxicação do Sistema Nervoso por Mercúrio/metabolismo , Compostos de Metilmercúrio/farmacocinética , Camundongos , Camundongos Endogâmicos C57BL , Atividade Motora/efeitos dos fármacos , Atividade Motora/fisiologia , Gravidez , Fatores Sexuais
14.
Hippocampus ; 13(1): 48-52, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12625456

RESUMO

In the present experiment, sham-operated (SH) and fornix-transected (FX) rats were trained on a new nonspatial, odor-guided task. On each session, eight odor pairs were presented twice. On the first occurrence of a pair, rats were reinforced for pushing the container (go response) in which the olfactory stimuli were placed. On the second occurrence, they were not reinforced and had to refrain from responding (no-go response) to be scored as success. Rats were first trained to criterion on odor pairs made of replicates of the same odor (S pairs). Then they were trained to criterion on pairs made of different odors, each member of the pair overlapping with that of another pair (O pairs) and finally, on pairs of different odors with no overlap (NO pairs). The results showed that the number of sessions to reach criterion was significantly higher in FX than in SH rats during training on O pairs, but not during training on S or on NO pairs. These findings are consistent with the configural (Rudy and Sutherland, 1995: Hippocampus 5:375-389) or relational (Eichenbaum et al., 1994: Behav Brain Sci 17:449-518) account of the hippocampal memory function.


Assuntos
Sinais (Psicologia) , Fórnice/lesões , Hipocampo/fisiopatologia , Deficiências da Aprendizagem/fisiopatologia , Transtornos da Memória/fisiopatologia , Condutos Olfatórios/fisiologia , Olfato/fisiologia , Animais , Fórnice/fisiopatologia , Fórnice/cirurgia , Aprendizagem/fisiologia , Deficiências da Aprendizagem/etiologia , Deficiências da Aprendizagem/patologia , Masculino , Memória/fisiologia , Transtornos da Memória/etiologia , Transtornos da Memória/patologia , Modelos Neurológicos , Desempenho Psicomotor/fisiologia , Ratos , Ratos Long-Evans
16.
Neurotoxicol Teratol ; 23(5): 463-72, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11711249

RESUMO

Pregnant C57BL/6 mice were orally given daily doses of 4 or 6 mg/kg of methylmercury chloride (MeHg) or vehicle during either gestational days 7-9 (GD7-9) or days 12-14 (GD12-14). Their female offspring were tested between 6 and 16 weeks of age on a variety of behavioral tasks. Motor coordination on the rotarod and visual discrimination learning in the Y maze were not affected by administration of MeHg either at GD7-9 or at GD12-14. In the open field, the total number of square crossings was lower in mice treated with 4 and 6 mg/kg of MeHg at GD12-14 than in control mice whether the environment was new or familiar, but prenatal administration of MeHg at GD7-9 had no effect on this measure. Administration of MeHg either at GD7-9 or at GD12-14 had no effect on the percentage of central square crossings or on the frequency of rearings in the open field. On spatial alternation training in the T maze, both treated groups in Condition GD7-9 and the group treated with 6 mg/kg at GD12-14 required more sessions to reach the learning criterion than their respective vehicle groups. When spatial alternation was tested with delays, treated groups did not differ from their respective control groups. In the radial arm maze, the performance of mice treated at GD7-9 was normal, but reference memory and working memory were impaired by administration of MeHg at GD12-14. In mice treated with 4 mg/kg of MeHg, reference memory was impaired only on the first block of trials, whereas in mice treated with 6 mg/kg, the deficit persisted on all blocks of trials. Overall, these results indicate that prenatal administration of MeHg at GD12-14 had more detrimental effects on behavioral performance than administration at GD7-9. It reduced locomotor activity and impaired reference memory for egocentric and allocentric spatial information as well as working memory for places.


Assuntos
Envelhecimento/fisiologia , Desenvolvimento Embrionário e Fetal , Aprendizagem/efeitos dos fármacos , Compostos de Metilmercúrio/toxicidade , Atividade Motora/efeitos dos fármacos , Efeitos Tardios da Exposição Pré-Natal , Desempenho Psicomotor/efeitos dos fármacos , Envelhecimento/efeitos dos fármacos , Animais , Encéfalo/metabolismo , Desenvolvimento Embrionário e Fetal/efeitos dos fármacos , Comportamento Exploratório/efeitos dos fármacos , Feminino , Idade Gestacional , Fígado/metabolismo , Compostos de Metilmercúrio/farmacocinética , Camundongos , Camundongos Endogâmicos C57BL , Gravidez , Percepção Espacial/efeitos dos fármacos , Distribuição Tecidual
17.
Hippocampus ; 8(4): 323-9, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9744419

RESUMO

Monkeys with removals of medial temporal lobe (MTL) structures are widely recognized as valid models of human global anterograde amnesia, a syndrome that arises consequent to damage to a finite set of brain structures situated in the medial temporal lobe and/or medial diencephalon. However, a comparison of memory deficits in human and nonhuman primates with MTL damage has presented a long-standing puzzle. Whereas amnesic patients are impaired in learning object discrimination problems, monkeys with MTL damage are typically not. One possible explanation for this difference is that object discrimination tasks for humans and monkeys differ in that the former but not the latter requires the use of contextual information. If this analysis is correct, monkeys with MTL damage might be disadvantaged in learning to discriminate similar objects presented in different contexts. To test this possibility, we evaluated the effects of excitotoxic lesions of one of the MTL structures, the hippocampus, on the rate of learning of discrimination problems embedded within unique contexts. Monkeys with hippocampal lesions were impaired relative to controls in learning object discrimination problems of this type. These findings strongly support the idea that the difference in the effect on object memory of MTL damage in human and nonhuman primates is due to a difference in the opportunity to employ contextual cues rather than to a difference in the organization of memory.


Assuntos
Hipocampo/fisiologia , Macaca mulatta/fisiologia , Memória/fisiologia , Animais , Aprendizagem por Discriminação/fisiologia
18.
Acta Haematol ; 99(2): 76-9, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9554453

RESUMO

Thromboembolic (TE) events have been frequently reported in beta-thalassemic patients in association with known risk factors such as diabetes, complex cardiopulmonary abnormalities, hypothyroidism, liver function anomalies, and postsplenectomy thrombocytosis. In a recent survey involving 9 Italian thalassemic centers, we identified 32 patients with TE episodes in a total of 735 subjects, of whom 683 had thalassemia major and 52 thalassemia intermedia, corresponding to 3.95 and 9.61%, respectively. There was a great variation in localization: the main one (16/32) was CNS, with a clinical picture of headache, seizures and hemiparesis. Other localizations were the pulmonary (3 patients), mesenteric (1 patient) and portal (2 patients) sites. There were 6 cases of deep venous thrombosis (2 in the upper limbs, 4 in the lower ones). Intracardiac thrombosis was found in 2 subjects and clinical and laboratory signs of DIC were observed in 2 others during pregnancy. Since our patients with TE events present a statistically significantly higher incidence of associated dysfunction (cardiomyopathy, diabetes, liver function anomalies, hypothyroidism) than those without TE events (50 vs. 13.8%), we suggest close monitoring of those patients who are at higher risk of developing TE events because of the presence of one or more of these predisposing factors.


Assuntos
Tromboembolia/etiologia , Talassemia beta/complicações , Adolescente , Adulto , Coagulação Sanguínea , Criança , Feminino , Humanos , Recém-Nascido , Masculino , Gravidez , Complicações Hematológicas na Gravidez
19.
Exp Brain Res ; 119(2): 131-40, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9535562

RESUMO

In macaque monkeys, aspiration but not excitotoxic lesions of the medial temporal lobe limbic structures, the amygdala and hippocampus, produce a severe impairment in visual recognition memory. Furthermore, certain ventromedial cortical regions, namely the rhinal (i.e., entorhinal and perirhinal) cortex, are now known to be critical for visual recognition memory. Because the route taken by temporal cortical efferent fibers, especially perirhinal efferents, passes nearby the amygdala, it is possible that inadvertent damage to these fibers is produced by the aspirative but not the excitotoxic process, thereby accounting at least in part for the different behavioral outcomes of the two types of lesion. To test this idea, we assessed the integrity of the rhinal corticothalamic projection system after aspiration lesions of the amygdala. Three rhesus monkeys with unilateral amygdala removals received bilaterally symmetrical injections of a retrograde fluorescent tracer into the medial portion of the mediodorsal nucleus of the thalamus. Retrogradely labeled cells were identified using conventional fluorescence microscopy techniques. In all three cases, the rhinal cortex of the intact hemispheres contained moderate numbers of retrogradely labeled cells. By contrast, the rhinal cortex of the amygdalectomized hemispheres consistently contained few retrogradely labeled cells, and a direct comparison of the two hemispheres showed this difference to be statistically significant. A similar asymmetric pattern was observed for area TE but not for the cortex lining the dorsal bank of the superior temporal sulcus, nor for the rostral cingulate motor area, which was examined as a control. The results indicate that aspiration lesions of the amygdala not only remove the cell bodies of the amygdala, as intended, but also inadvertently disrupt projection fibers arising from cells in the rhinal cortex and area TE that pass nearby or through the amygdala en route to the thalamus. Behavioral studies examining the effects of aspiration lesions of the amygdala in nonhuman primates need to take these findings into consideration.


Assuntos
Tonsila do Cerebelo/fisiopatologia , Córtex Cerebral/fisiopatologia , Sistema Límbico/fisiopatologia , Sucção , Transmissão Sináptica/fisiologia , Tálamo/fisiopatologia , Animais , Encefalopatias/etiologia , Encefalopatias/fisiopatologia , Mapeamento Encefálico , Inalação , Macaca mulatta
20.
Eur J Haematol ; 58(5): 320-5, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9222287

RESUMO

The -175 (T-->C) G gamma hereditary persistence of fetal haemoglobin is a very rare promoter mutation occurring in Caucasians as well as in African-Americans. Heterozygotes for this non-deletional HPFH show 20% HbF, mostly of G gamma type. We describe here a healthy Sardinian man who coinherited -175 (T-->C) G gamma HPFH with the beta-thalassaemia codon 39 nonsense mutation in trans; he showed 64% HbF, 100% of G gamma type. Although the beta-globin haplotype pattern (II/II) was indicative of the presence of the A gamma T allele on both chromosomes, the A gamma T expression was undetectable by HPLC even in red cell populations separated by age. The proband was, moreover, homozygous for the -4 bp deletion at position -225 to -222 of A gamma promoter which has recently been associated with decreased A gamma T globin expression. These findings suggest that this maximal overexpression of G gamma-globin probably reflects intensified stimulation of the mutated G gamma promoter in this hitherto undescribed genetic condition.


Assuntos
Hemoglobina Fetal/genética , Hemoglobinopatias/genética , Talassemia beta/genética , gama-Globulinas/genética , Adulto , Saúde da Família , Hemoglobina Fetal/química , Expressão Gênica , Heterozigoto , Humanos , Itália/epidemiologia , Masculino , Mutação , Prevalência , Talassemia beta/epidemiologia , gama-Globulinas/química
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