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1.
Drug Dev Res ; 78(8): 411-419, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28921601

RESUMO

Preclinical Research Δ9 -Tetrahydrocannabinol (THC) is a hydrophobic compound that has a potent antinociceptive effect in animals after intrathecal (IT) or intracerebroventricular (ICV) administration. The lack of a suitable solvent precludes its IT administration in humans. 2-Hydroxypropyl-ß-cyclodextrin (HPßCD) increases the water solubility of hydrophobic drugs and is approved for IT administration in humans. To investigate whether HPßCD might be a suitable carrier for ICV administration of THC in rats, two formulations containing THC complexed with HPßCD (30 and 135 µg of THC per animal) and vehicle were administered to Wistar rats. The antinociceptive effect (using the tail flick test), locomotor activity, and body temperature were evaluated. ICV injection of 135 µg of THC/HPßCD complex increased tail flick latency, reduced locomotor activity, and had a dual effect on body temperature. The 30 µg THC/HPßCD formulation only produced a hyperthermic effect. All animals appeared healthy, with no difference between the groups. These results were similar to those obtained in other preclinical studies in which THC was administered centrally using solvents that are unsuitable for IT administration in humans because of their toxicity. Our findings suggest that HPßCD may be a useful carrier for IT administration of THC in humans. Drug Dev Res 78 : 411-419, 2017. © 2017 Wiley Periodicals, Inc.


Assuntos
2-Hidroxipropil-beta-Ciclodextrina/química , Analgésicos não Narcóticos/administração & dosagem , Temperatura Corporal/efeitos dos fármacos , Dronabinol/administração & dosagem , Locomoção/efeitos dos fármacos , 2-Hidroxipropil-beta-Ciclodextrina/farmacologia , Analgésicos não Narcóticos/química , Analgésicos não Narcóticos/farmacologia , Animais , Dronabinol/química , Dronabinol/farmacologia , Portadores de Fármacos , Composição de Medicamentos , Avaliação Pré-Clínica de Medicamentos , Injeções Espinhais , Masculino , Ratos , Ratos Wistar , Solubilidade
2.
Commun Agric Appl Biol Sci ; 79(2): 199-203, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-26084097

RESUMO

Since its first detection in Sardinia (Italy), Tuta absoluta (Meyrick) has been reported as a major pest of greenhouse tomatoes. In recent years, however, a tendency toward a progressive reduction of tomato borer infestation levels has been observed. The reasons behind this decline are probably diverse, including both the increase in growers' ability to manage the pest and the adaptation of native predators and parasitoids to the new prey/host. In order to assess the species composition of the parasitoid complex associated with T. absoluta larvae in Sardinian greenhouse tomatoes, a two-year (2010/11) survey was conducted in one of the island's major horticultural areas (Pula, Cagliari). An estimate of the levels of parasitism caused by native wasps was also carried out. The occurrence of larval parasitoids of T. absoluta was detected in approximately half of the crops monitored. The average parasitism rate recorded in tomato plants infested by tomato borer larvae was 1.3%. Moreover, while no parasitism was observed in 76.4% of the samples collected, only 3.0% of the samples showed a parasitism rate exceeding 10%. The highest rates were recorded in spring and summer, with a peak in July (4.8%). Of 159 adult parasitoids recovered from infested leaves, 62.9% were found to belong to a Necremnus sp. near artynes (Walker), 34.6% to a Necremnus sp. near tidius (Walker), and 2.5% to Neochrysocharis formosa (Westwood) (Hymenoptera: Eulophidae). These results show that some native parasitoids have adapted to T. absoluta in the study area. Although parasitoid abundance in tomato crops appeared to be low, their contribution for the control of tomato borer infestation could possibly be enhanced through the application of conservation biological control measures.


Assuntos
Mariposas/fisiologia , Doenças das Plantas/parasitologia , Solanum lycopersicum/parasitologia , Vespas/crescimento & desenvolvimento , Animais , Feminino , Itália , Larva/crescimento & desenvolvimento , Masculino , Controle Biológico de Vetores , Doenças das Plantas/prevenção & controle , Estações do Ano
3.
Behav Brain Res ; 453: 114625, 2023 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-37567256

RESUMO

Neonatal handling (NH) is an environmental manipulation that induces long-lasting changes in behavioural, neuroendocrine, and neuroanatomical processes in rodents. We have previously reported that NH treatment increases social interaction preference in an animal model of schizophrenia-relevant features, the Roman high-avoidance (RHA) rats. The present study was aimed at evaluating whether the increase of social behaviour/preference due to NH treatment in RHA rats is associated with differences in c-Fos expression levels in some of the brain areas that integrate the "social brain". To this aim, we evaluated the performance of adult male rats from both Roman rat strains (RHA vs. RLA -Roman low-avoidance- rats), either untreated (control) or treated with NH (administered during the first 21 days of life) in a social interaction task. For the analyses of c-Fos activation untreated and NH-treated animals were divided into three different experimental conditions: undisturbed home cage controls (HC); rats exposed to the testing set-up context (CTX); and rats exposed to a social interaction (SI) test. It was found that, compared with their RLA counterparts, NH treatment increased social behaviour in RHA rats, and also specifically enhanced c-Fos expression in RHA rats tested for SI in some brain areas related to social behaviour, i.e. the infralimbic cortex (IL) and the medial posterodorsal amygdala (MePD) regions.


Assuntos
Esquizofrenia , Animais , Masculino , Ratos , Animais Recém-Nascidos , Aprendizagem da Esquiva/fisiologia , Encéfalo , Proteínas Proto-Oncogênicas c-fos/metabolismo
4.
Biomech Model Mechanobiol ; 22(5): 1645-1683, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37169958

RESUMO

The interest in the properties of animal soft tissues is often related to the desire to find an animal model to replace human counterparts due to the unsteady availability of human tissues for experimental purposes. Once the most appropriate animal model is identified, it is possible to carry out ex-vivo and in-vivo studies for the repair of ligamentous tissues and performance testing of replacement and support healing devices. This work aims to present a systematic review of the mechanical properties of ligaments reported in the scientific literature by considering different anatomical regions in humans and several animal species. This study was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) method. Moreover, considering the lack of a standard protocol for preconditioning of tissues, this aspect is also addressed. Ninety-six studies were selected for the systematic review and analysed. The mechanical properties of different animal species are reported and summarised in tables. Only results from studies reporting the strain rate parameter were considered for comparison with human ligaments, as they were deemed more reliable. Elastic modulus, ultimate tensile stress, and ultimate strain properties are graphically reported identifying the range of values for each animal species and to facilitate comparison between values reported in the scientific literature in animal and human ligaments. Useful similarities between the mechanical properties of swine, cow, and rat and human ligaments have been found.


Assuntos
Ligamentos , Feminino , Bovinos , Humanos , Suínos , Animais , Ratos , Resistência à Tração , Fenômenos Biomecânicos , Módulo de Elasticidade
5.
Proc Nutr Soc ; 81(1): 1-11, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34726148

RESUMO

The liver is a key metabolic organ that undertakes a multitude of physiological processes over the course of a day, including intrahepatic lipid and glucose metabolism which plays a key role in the regulation of systemic lipid and glucose concentrations. It serves as an intermediary organ between exogenous (dietary) and endogenous energy supply to extrahepatic organs. Thus, perturbations in hepatic metabolism can impact widely on metabolic disease risk. For example, the accumulation of intra-hepatocellular TAG (IHTG), for which adiposity is almost invariably a causative factor may result in dysregulation of metabolic pathways. Accumulation of IHTG is likely due to an imbalance between fatty acid delivery, synthesis and removal (via oxidation or export as TAG) from the liver; insulin plays a key role in all of these processes.


Assuntos
Resistência à Insulina , Hepatopatia Gordurosa não Alcoólica , Ácidos Graxos/metabolismo , Glucose/metabolismo , Humanos , Metabolismo dos Lipídeos/fisiologia , Fígado/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo , Obesidade/metabolismo
6.
J Dermatolog Treat ; 33(3): 1638-1642, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-33555951

RESUMO

INTRODUCTION: This is an Italian single-center retrospective study evaluating safety and efficacy of biologic agents in psoriatic patients with a previous diagnosis of malignant cancer. AIM: Management of moderate and severe psoriasis patients with a past medical history of malignancies could be difficult because biologic agents are historically associated with a presumptive increased risk of neoplastic reactivation or of a new incoming cancer. The aim of this study is to assess the safety of biologics in patients with a previous cancer diagnosis. MATERIAL AND METHODS: The study analyzed 16 moderate to severe psoriasis patients with a diagnosis of malignant cancer in the previous 10 years treated with biologic agents for up to at least 96 weeks. In five of these patients, cancer was diagnosed in the previous 5 years. RESULTS: We observed a rapid decrease in PASI (psoriasis area severity index) reaching a 90% improvement in 100% of patients. Oncologic follow up did not show any worsening or reactivation of cancer during the entire observation period. No new malignancies were observed in the analyzed sample. CONCLUSIONS: Biologic agents in our experience have demonstrated to be safe and effective in psoriatic patients with a past medical history of malignant cancer.


Assuntos
Terapia Biológica , Neoplasias , Psoríase , Anticorpos Monoclonais/uso terapêutico , Humanos , Neoplasias/induzido quimicamente , Neoplasias/complicações , Psoríase/patologia , Estudos Retrospectivos , Índice de Gravidade de Doença , Resultado do Tratamento
7.
Eur Rev Med Pharmacol Sci ; 24(22): 11914-11918, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33275263

RESUMO

OBJECTIVE: Herein we report clinical and virological data in a patient with COVID-19 infection and a prior history of kidney transplantation who had a good clinical recovery despite systemic infection. PATIENTS AND METHODS: Reverse transcriptase quantitative PCR analysis for the RdRp, N and E target genes detected viral RNA in different types of biological specimens. Whole viral genome sequences were obtained and analyzed from respiratory tract, feces and blood. RESULTS: Viral sequences showed high (~99.9%) homology with the Wuhan seafood market pneumonia virus. Phylogenetic analysis assigned of the SARS-CoV-2 strains to clade G. A rare variant in the orf1ab gene was present in both sequences, while a missense variant was detected only in viral RNA from stool. CONCLUSIONS: The evolution of the COVID-19 systemic infection in the patient presented here was favorable to the hypothesis that immunosuppressive therapy in organ transplant recipients might be involved in viral dissemination. A missense mutation was present in only one specimen from the same patient implying the occurrence of a mutational event in viral RNA, which is suggestive for the presence of an active virus, even though viral isolation is necessary to demonstrate infectivity.


Assuntos
COVID-19/virologia , Fezes/virologia , Transplante de Rim , Nasofaringe/virologia , RNA Viral/genética , Proteínas Virais/genética , Fezes/química , Feminino , Rejeição de Enxerto/prevenção & controle , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Imunossupressores/uso terapêutico , Pessoa de Meia-Idade , Mutação de Sentido Incorreto/genética , Nasofaringe/química , Filogenia , Poliproteínas/genética , RNA Viral/sangue , SARS-CoV-2/genética , Análise de Sequência de RNA
8.
Commun Agric Appl Biol Sci ; 74(2): 363-73, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-20222592

RESUMO

To evaluate the effectiveness of alternative options for biocontrol of whiteflies in greenhouse tomatoes, an experiment was carried out during the cropping season 2005-2006 in one of Sardinia's major horticultural districts (S. Margherita di Pula, Cagliari, Italy). Twelve long-cycle and 17 short-cycle tomato crops (8 autumn and 9 spring crops) were surveyed. All of them were treated for insect pest control at the beginning of the growing season, but in 19 out of 29 cases whitefly natural enemies were also released (BCA greenhouses), at least four weeks after the last treatment. The following release programmes were tested: on autumn crops, 1 Macrolophus caliginosus and 12 Eretmocerus mundus/m2; on long-cycle crops, 1 M. caliginosus (released in autumn or spring) and 24 Encarsia formosa/m2 or 48 E. formosa/m2; on spring crops, 1 M. caliginosus and 24 E. formosa/m2 or 48 E. formosa/m2. The cost of each option was fixed at approximately 0.25 Euros/m2. The remaining greenhouses were maintained as controls (no BCA greenhouses). While whitefly and mirid populations were monitored monthly, whitefly species composition and mortality of immature stages were estimated at least twice during the growing season. On short-cycle autumn crops, the release of M. caliginosus and E. mundus produced negligible results in terms of Bemisia tabaci control. On long-cycle and spring crops, even though in June mortality rates in BCA greenhouses were found to be 2- to 3-fold higher than in no-BCA greenhouses, Trialeurodes vaporariorum population growth was not significantly affected by natural enemies. Among the beneficials tested, E. formosa proved to be the most effective; E. mundus and M. caliginosus did not establish well, probably owing to the persistence of insecticide residues, scarce prey availability and intense plant de-leafing. The presence of indigenous natural enemies of whiteflies was observed in most sites, but in general they contributed little to biological control. The present experiment showed that in Sardinian tomato greenhouses the use of beneficial insects may result in inadequate biocontrol of whiteflies. In particular, the application of cultural practices which may disrupt the establishment and development of predator and parasitoid populations should be critically reexamined.


Assuntos
Hemípteros/parasitologia , Hemípteros/patogenicidade , Controle Biológico de Vetores/métodos , Solanum lycopersicum/parasitologia , Animais , Produtos Agrícolas/parasitologia , Interações Hospedeiro-Parasita , Itália , Ninfa/parasitologia , Pupa/parasitologia , Estações do Ano
10.
Commun Agric Appl Biol Sci ; 74(2): 343-52, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-20222589

RESUMO

The whiteflies Bemisia tabaci and Trialeurodes vaporariorum and their associated viruses constitute a major threat to tomato crops in the Mediterranean region. Continuous host availability and mild climate are thought to be among the factors contributing to the outbreaks of whitefly-related problems in this area. We carried out a year-long survey to investigate the relative contribution of different plants, agricultural and not, and indoor/outdoor crops as hosts of the two whiteflies and the tomato yellow leaf curl disease (TYLCD) in a multi-crop system typical of tomato growing areas in southern Sardinia (S. Margherita di Pula, Cagliari, Italy). For this purpose, during 2005 we monitored whitefly population trends in different plots of a horticulture farm, evaluated seasonal changes in the infestation density of the two pests on the most represented host species and assessed the incidence of TYLCD on tomato crops and susceptible weeds. Whitefly catches on yellow sticky traps were found to be higher inside et along the external perimeter of greenhouses compared to open field crops or uncultivated areas, thus suggesting significant adult movement between indoor and outdoor patches. In most plots flight activity increased between late spring and late summer, peaking in July. The number of immatures of the two whitefly species showed similar dynamics, but while T. vaporariorum reached the highest densities in greenhouse tomato crops in June, peak levels of 8. tabaci were recorded between July and August in outdoor horticultural crops and weeds. The occurrence of TYLCD was detected all year round on weed hosts, but the highest number of infected plants was observed in June on long cycle tomato crops. The present survey has demonstrated the contribution of non-agricultural plants the maintenance of tomato yellow leaf curl disease in the study site. However, tomato crops established in summer as major reservoirs of TYLCD-associated viruses and presumably played a key role in the spread of the disease to autumn tomato crops. The implementation of a crop-free period between successive susceptible crops, or at least the avoiding of whitefly movement through greenhouse openings and the complete destruction of plants after final harvest, would probably reduce the severity of TYLCD epidemics in this area.


Assuntos
Ceratitis capitata , Produtos Agrícolas/parasitologia , Hemípteros , Densidade Demográfica , Solanum lycopersicum/parasitologia , Animais , Ceratitis capitata/patogenicidade , Produtos Agrícolas/crescimento & desenvolvimento , Ectoparasitoses/epidemiologia , Hemípteros/patogenicidade , Itália , Região do Mediterrâneo/epidemiologia , Pupa/fisiologia , Estações do Ano
11.
Commun Agric Appl Biol Sci ; 74(3): 831-41, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-20222569

RESUMO

Tomato yellow leaf curl Sardinia virus (TYLCSV) and Tomato yellow leaf curl virus (TYLCV) are among the most virulent pathogens of greenhouse tomatoes in Sardinia (Italy). To investigate the relationship between seasonal population trends of the vector Bemisia tabaci and the dynamics of TYLCD spread to susceptible crops, between May and October 2007 we carried out a survey in a tomato growing area located in the south of the island. On three farms specialized in the production of fresh market tomatoes we monitored, outside commercial greenhouses, the following parameters related to TYLCD epidemiology: mean weekly catches of the whiteflies B. tabaci and Trialeurodes voporariorum on yellow sticky traps, ratio between the two whitefly species and proportion of B. tabaci adults carrying TYLCSV/TYLCV in adult samples collected on hosts not susceptible to the disease, proportion of tomato plants infected by TYLCSV/TYLCV after a two-week exposure to open field conditions. Generally speaking, the flight activity of whiteflies increased during spring, reached a peak in May or June and gradually declined in summer. At the beginning of the survey, T. vaporariorum was found to be the prevalent species, but after a shift in composition of whitefly populations during July, B. tabaci became predominant. While the percentage of vector adults carrying the viral agents of the disease was relatively high up to July, with maximum values ranging between 14 and 25%, during the following months it decreased to less than 5%. The incidence of TYLCD in the plants exposed outside the greenhouses showed a similar trend in the sites surveyed, with two peaks roughly coinciding with the beginning and end of summer. Therefore, two distinct phases of TYLCD spread were observed: from spring to midsummer when the disease was transmitted by low 8. tabaci populations with relatively high proportions of virus carriers; from midsummer to autumn, when the disease was spread by larger vector populations with low percentages of individuals carrying the viruses. Further studies are necessary to gain a better understanding of the interactions among B. tabaci biotypes, TYLCSV/TYLCV and their hosts.


Assuntos
Begomovirus/patogenicidade , Doenças das Plantas/virologia , Solanum lycopersicum/virologia , Animais , Produtos Agrícolas/virologia , Hemípteros/crescimento & desenvolvimento , Hemípteros/virologia , Incidência , Controle de Insetos/métodos , Itália/epidemiologia , Região do Mediterrâneo , Doenças das Plantas/estatística & dados numéricos , Solanum melongena/parasitologia
12.
Injury ; 50 Suppl 4: S26-S29, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30691923

RESUMO

INTRODUCTION: Hip fracture is a common serious injury that occurs mainly in elderly. Dual-mobility hip arthroplasty or bipolar emiarthroplasty for its treatment remains a controversial decision. Co-morbidities and risk of fall represent additional aspects to be considered. The aim of our study was to determine the rate of mechanical complications for these two types of implants related to fall risk status of patients. PATIENTS AND METHODS: Our study is a retrospective clinical trial of patients operated with a biarticular hemiarthroplasty or a dual-mobility total hip arthroplasty. Primary outcome was dislocation rate and need for any revision procedure. Patients were treated in a single center from January 2013 to March 2017. In all cases Morse Fall Scale (MSF) was calculated at patient admission to evaluate the risk of postoperative fall. Inclusion criteria to the study were: subcapital or femoral neck fracture of non-pathologic nature, patients with neuromuscular disorders or cognitive dysfunction, age > 75 years with MFS ≥ 45. The patients were reviewed postoperatively at 8 weeks, 6 months, 12 months, and then annually. Patients had clinical (Harris hip score) and radiological assessment. RESULTS: The mean duration of the follow-up was 283 months. There were five dislocations in Group A (5,6%) and no dislocations in Group B (0%). All dislocations occurred within the first 6 months after surgery. The mean Harris Hip score was 81,7 in Group A patients and 79, 8 in Group B patients. DISCUSSION: Treatment of hip fractures on non-cooperative patients still represents a dilemma. Falls and runaway motions represent high risk factors of dislocation. Use of dual-mobility cup has been found to be associated with a not statistically proved decrease of dislocation compared to traditional cups. CONCLUSION: Dual-mobility cups might be considered a valuable option to prevent postoperative dislocation but further study is needed before extending the indications for dual-mobility following a fracture of the femoral neck, to assess the potential cost and complications of a longer procedure. So far, despite a lower dislocation risk, the authors actually cannot recommend widely use of a dual-motility cup instead of emiarthroplasty in high falls risk patients.


Assuntos
Acidentes por Quedas/estatística & dados numéricos , Geriatria , Hemiartroplastia/efeitos adversos , Luxação do Quadril/prevenção & controle , Instabilidade Articular/prevenção & controle , Desenho de Prótese/instrumentação , Feminino , Humanos , Masculino , Falha de Prótese , Estudos Retrospectivos , Medição de Risco
13.
J Med Case Rep ; 12(1): 186, 2018 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-29941025

RESUMO

BACKGROUND: Sacral fractures with spinopelvic dissociation are rare, and hard to diagnose and treat. Fractures with a H- or U-shaped line are severely unstable, due to a dissociation of the spine and of the upper body of the sacrum from the pelvis. They are commonly due to high-energy trauma events, with severe neurological injuries in 80% of cases. CASES PRESENTATION: Five polytraumatized Caucasian patients, three women and two men (mean age: 34 years old) with spinopelvic dissociation were selected. All patients underwent level I-II examinations with radiographs and computed tomography total-body scans; all patients needed damage-control procedures. Sacral fractures were classified according to Denis and Roy-Camille classifications, and neurologic injuries of cauda equina according to Gibbons classification. Patients' outcome was analyzed with the Majeed score. Definitive surgical treatment was appropriate for two patients (lumbar-pelvic fixation or transverse bar). Clinical and radiographic outcomes were analyzed periodically. Four patients survived, all of them suffered severe neurologic deficits. One case of osteomyelitis was treated with the removal of the fixation implants 23 months after the accident. CONCLUSIONS: Diagnosis of spinopelvic dissociation is frequently overlooked due to the severe associated injuries affecting these patients. In cases of a fall from high height, this lesion should be investigated with a lateral sacral radiographic view and computed tomography scan of the pelvis. If untreated, it can lead to severe and progressive neurologic deficit with muskuloskeletal deformities and persistent pain. Early decompression treatment is controversial, but an early lumbopelvic fixation is recommended. A correct diagnosis and early treatment can reduce morbidity and strongly improve the outcome of these patients.


Assuntos
Fraturas Ósseas , Fraturas da Coluna Vertebral , Tentativa de Suicídio , Adulto , Feminino , Fixação Interna de Fraturas , Humanos , Ílio , Masculino , Pessoa de Meia-Idade , Sacro/lesões , Fraturas da Coluna Vertebral/etiologia , Fraturas da Coluna Vertebral/cirurgia
14.
Neuroscience ; 147(1): 197-206, 2007 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-17507169

RESUMO

[N-(piperidin-1-yl)-5-(4-chlorophenyl)-4-methyl-1H-pyrazole-3-carboxyamide] (SR 141716A), a selective cannabinoid CB1 receptor antagonist, injected into the paraventricular nucleus of the hypothalamus (PVN) of male rats, induces penile erection. This effect is mediated by the release of glutamic acid, which in turn activates central oxytocinergic neurons mediating penile erection. Double immunofluorescence studies with selective antibodies against CB1 receptors, glutamic acid transporters (vesicular glutamate transporters 1 and 2 (VGlut1 and VGlut2), glutamic acid decarboxylase-67 (GAD67) and oxytocin itself, have shown that CB1 receptors in the PVN are located mainly in GABAergic terminals and fibers surrounding oxytocinergic cell bodies. As GABAergic synapses in the PVN impinge directly on oxytocinergic neurons or on excitatory glutamatergic synapses, which also impinge on oxytocinergic neurons, these results suggest that the blockade of CB1 receptors decreases GABA release in the PVN, increasing in turn glutamatergic neurotransmission to activate oxytocinergic neurons mediating penile erection. Autoradiography studies with [(3)H](-)-CP 55,940 show that chronic treatment with SR 141716A for 15 days twice daily (1 mg/kg i.p.) significantly increases the density of CB1 receptors in the PVN. This increase occurs concomitantly with an almost twofold increase in the pro-erectile effect of SR 141716A injected into the PVN as compared with control rats. The present findings confirm that PVN CB1 receptors, localized mainly in GABAergic synapses that control in an inhibitory fashion excitatory synapses, exert an inhibitory control on penile erection, demonstrating for the first time that chronic blockade of CB1 receptors by SR 141716A increases the density of these receptors in the PVN. This increase is related to an enhanced pro-erectile effect of SR 141716A, which is still present 3 days after the end of the chronic treatment.


Assuntos
Inibição Neural/efeitos dos fármacos , Núcleo Hipotalâmico Paraventricular/metabolismo , Ereção Peniana/fisiologia , Receptor CB1 de Canabinoide/metabolismo , Animais , Ácido Glutâmico/metabolismo , Imuno-Histoquímica , Masculino , Microinjeções , Inibição Neural/fisiologia , Neurotransmissores/administração & dosagem , Ocitocina/metabolismo , Núcleo Hipotalâmico Paraventricular/efeitos dos fármacos , Núcleo Hipotalâmico Paraventricular/fisiologia , Ereção Peniana/efeitos dos fármacos , Piperidinas/administração & dosagem , Pirazóis/administração & dosagem , Ratos , Ratos Sprague-Dawley , Receptor CB1 de Canabinoide/antagonistas & inibidores , Rimonabanto , Comportamento Sexual Animal/efeitos dos fármacos , Comportamento Sexual Animal/fisiologia , Transdução de Sinais/fisiologia , Distribuição Tecidual , Ácido gama-Aminobutírico/metabolismo
15.
Cell Prolif ; 35(3): 143-54, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12027950

RESUMO

Atherosclerosis is an inflammatory-fibroproliferative response of the arterial wall involving a complex set of interconnected events where cell proliferation (lymphomonocytes, and endothelial and smooth-muscle cells) and substantial perturbations of intracellular cholesterol metabolism are considered to be among the main features. Glucose-6-phosphate dehydrogenase (G6PD), the key enzyme of the hexose-monophosphate shunt pathway, is an essential enzyme involved in both cell growth and cholesterol metabolism, raising the question as to whether G6PD deficiency may have metabolic and growth implications in a deficient population. In the present study, we investigated cell growth and cholesterol metabolism in peripheral blood lymphomononuclear cells (PBMC) from G6PD-normal (n = 5) and -deficient (n = 5) subjects stimulated with lectins (phytohaemoagglutinin and Concanavalin A). G6PD activity, DNA ([3H]-thymidine incorporation) cholesterol synthesis and esterification ([14C]-acetate and [14C]-oleate incorporation), and G6PD, HMGCoA reductase and low density lipoprotein (LDL) receptor mRNA levels (RT-PCR) all increased following lectin stimulation in both normal and G6PD-deficient cells. However, these parameters were significantly lower in G6PD-deficient cells (P < 0.05). It is of interest that G6PD-deficient PBMC, which showed lower expression of G6PD and higher expression of the LDL receptor gene than normal PBMC under basal conditions, exhibited an opposite pattern after stimulation: G6PD and HMGCoA reductase being expressed at significantly higher levels in deficient than in normal cells (P < 0.05). We conclude that the reduced capability of G6PD-deficient cells to respond to mitogenic stimuli and to synthesize cholesterol esters may represent favourable conditions for reducing the risk of cardiovascular diseases.


Assuntos
Colesterol/metabolismo , Deficiência de Glucosefosfato Desidrogenase/enzimologia , Deficiência de Glucosefosfato Desidrogenase/metabolismo , Leucócitos Mononucleares/enzimologia , Leucócitos Mononucleares/metabolismo , Adulto , Arteriosclerose/etiologia , Divisão Celular , Células Cultivadas , DNA/biossíntese , Glucosefosfato Desidrogenase/genética , Glucosefosfato Desidrogenase/metabolismo , Deficiência de Glucosefosfato Desidrogenase/genética , Humanos , Hidroximetilglutaril-CoA Redutases/biossíntese , Hidroximetilglutaril-CoA Redutases/genética , Cinética , Lipídeos/sangue , Masculino , RNA Mensageiro/biossíntese , Receptores de LDL/biossíntese , Receptores de LDL/genética
16.
Cell Prolif ; 32(1): 49-61, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10371303

RESUMO

A positive correlation between cholesterol esterification and growth rate potential was previously found in our laboratory during the growth of CEM and MOLT4 lymphoblastic cells. In the current study, we investigated whether the rates of cholesterol esters synthesis correlate with changes of acyl-CoAcholesterol acyltransferase (ACAT) mRNA levels and of other genes implied in cholesterol biosynthesis and uptake, such as 3-hydroxy-3-methylglutaryl-CoA (HMGCoA) reductase and low density lipoprotein (LDL) receptor. The results showed that the more rapid growing CEM cells had lower levels of expression of HMGCoA-reductase and LDL receptors compared to MOLT4. By contrast, ACAT mRNA levels were higher in CEM cells, further supporting the concept of a possible involvement of cholesterol esters in the regulation of cell growth and division. In this study, high levels of cholesterol esterification and of expression of ACAT gene were also associated with a markedly increased expression of multidrug resistance (MDR1) gene, suggesting that MDR1 activity might contribute to regulate the rate of cell growth and division by modulating intracellular cholesterol ester levels.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Ésteres do Colesterol/metabolismo , Leucemia de Células T , Animais , Divisão Celular/fisiologia , Colesterol/biossíntese , Primers do DNA , Regulação Enzimológica da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Hidroximetilglutaril-CoA Redutases/genética , Hidroximetilglutaril-CoA Redutases/metabolismo , Camundongos , RNA Mensageiro/análise , Receptores de LDL/genética , Receptores de LDL/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Esterol O-Aciltransferase/genética , Esterol O-Aciltransferase/metabolismo , Células Tumorais Cultivadas/química , Células Tumorais Cultivadas/citologia , Células Tumorais Cultivadas/enzimologia
17.
Cancer Lett ; 140(1-2): 53-8, 1999 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-10403541

RESUMO

In the present study we examined gene expression and glucose-6-phosphate dehydrogenase (G6PD) activity in leukemic cells isolated from G6PD normal and deficient subjects. The results have shown that G6PD activity strongly increases in G6PD normal leukemic cells as well as in G6PD deficient leukemic cells when compared to peripheral blood mononuclear cells (PBMC). Higher levels of G6PD gene expression were observed in leukemic cells from G6PD deficient patients compared to G6PD normal. A similar pattern of gene expression was also observed for 3-hydroxy-3-methylglutaryl coenzyme A (HMGCoA) reductase. These results support the hypothesis that G6PD deficient cell, in order to sustain their growth, must respond to the low activity of their mutant enzyme with an increase in quantity through an induction of gene expression.


Assuntos
Expressão Gênica , Deficiência de Glucosefosfato Desidrogenase/enzimologia , Glucosefosfato Desidrogenase/metabolismo , Leucemia/enzimologia , Adulto , Células Cultivadas , Humanos , Hidroximetilglutaril-CoA Redutases/metabolismo , Leucemia/metabolismo , Leucócitos Mononucleares/enzimologia , Leucócitos Mononucleares/metabolismo , Masculino , Reação em Cadeia da Polimerase , RNA Mensageiro/metabolismo , Receptores de LDL/metabolismo
18.
J Pharm Biomed Anal ; 13(1): 65-71, 1995 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7718636

RESUMO

Previous studies from the authors' laboratories have shown that cancer patients are characterized by lower levels of high-density lipoprotein cholesterol (HDL-C) compared with those of normal subjects. HDLs are a complex class of lipoproteins which can be divided mainly into two categories, HDL2 and HDL3, that have not only different lipid and protein composition but also different functions. Therefore, for a better understanding of the metabolism of HDL during tumour growth, the different subfractions of HDL (HDL2 and HDL3) were analysed in the serum of neoplastic patients using a rapid and simple high-performance liquid chromatography (HPLC) method for the analysis. The results obtained showed that serum from neoplastic patients exhibits a peculiar pattern in the distribution of HDL subfractions, consisting of a sharp decrease in HDL3 and a consequent increase of the normal HDL2/HDL3 ratio. It is suggested that evaluation of the HDL subfractions may be of clinical relevance for cancer status and that due to its simplicity, short analytical time and small sample volume required, the HPLC technique used in this study can be easily applied to routine analysis in cancer patients.


Assuntos
Lipoproteínas HDL/sangue , Lipoproteínas HDL/isolamento & purificação , Neoplasias/sangue , Adulto , Idoso , Feminino , Humanos , Lipoproteínas HDL2 , Lipoproteínas HDL3 , Lipoproteínas LDL/sangue , Lipoproteínas LDL/isolamento & purificação , Lipoproteínas VLDL/sangue , Lipoproteínas VLDL/isolamento & purificação , Masculino , Pessoa de Meia-Idade , Valores de Referência
19.
Minerva Med ; 69(60): 4181-92, 1978 Dec 08.
Artigo em Italiano | MEDLINE | ID: mdl-740321

RESUMO

An evaluation was made of the incidence of hypoparathyroidism after 131I management of hyperthyroidism and of the effect of irradiation on the relation between blood calcium, phosphorus and proteins and age in normal subjects. 356 treated patients and 216 controls were examined. Serum calcium was determined from 2 to 6 yr after treatment. It was found that calcium values decrease with age in males, wherease in women this phenomenon is less marked and, indeed, is no longer apparent over the age of 30. In the normal male, phosphrous also decreases with age, while in females there is a fall until the age of 30-40 yr, followed by a rise. Only 1 subject with a value of 8.45 mg calcium/100 ml was noted in the treated group and there was no significant difference between the means for the two groups, suggesting that parathyroid insufficiency is a virtually non-existent complication of the 131I treatment of hyperthyroidism. The relation between blood calcium and phosphorus and age in the treated group was examined with reference to subjects with normal thyroid function only. In the case of calcium, values were no longer related to age after treatment in males, while phosphorus values fell to below those observed in females, coupled with an increase in function of age as in women, though this itself was not statistically significant. Treatment also suppressed the relation between total blood proteins and age noted in the normal male. None of the parameters considered displayed any significant changes in the treated females. It would thus seem that 131I abolishes the differences in blood calcium and phosphorus mean values and age-linked patterns normally found between males and females.


Assuntos
Cálcio/sangue , Hipertireoidismo/radioterapia , Radioisótopos do Iodo/uso terapêutico , Fósforo/sangue , Adulto , Fatores Etários , Idoso , Proteínas Sanguíneas/metabolismo , Feminino , Humanos , Hipertireoidismo/sangue , Iodoproteínas/metabolismo , Masculino , Pessoa de Meia-Idade , Albumina Sérica/metabolismo , Fatores Sexuais
20.
Med Lav ; 93(3): 176-83, 2002.
Artigo em Italiano | MEDLINE | ID: mdl-12197267

RESUMO

OBJECTIVES: The aim of this paper was both to evaluate the internal dose of Hg in occupationally exposed workers (35 Chloralkali workers) compared to that of non occupationally exposed controls (40 workers of the same plant of Portotorres and 22 residents on the island of Carloforte, usual consumers of local fish, mostly tuna fish with relatively high Hg levels) and to assess the relevance of environmental and individual exposure factors linked to lifestyle, sea fish consumption and amalgam fillings. METHODS: All subjects filled out a questionnaire concerning the working history and lifestyle. The amalgam fillings area was measured by medical inspection using a standardised schedule attached to the questionnaire. Mercury in urine (HgU) was measured in all cases, while in a subgroup of our study total blood mercury (HgB) and its organic and inorganic component were also assessed. Furthermore, for 8 of the Carloforte group mercury in hair was also available. RESULTS: Values of urinary mercury excretion of the Chloralkali workers were significantly higher (median value of 15.4, range 4.8-35.0 micrograms/g creatinine, 94.3% of the cases having values > 5 micrograms/g creatinine) than those observed both among the reference group (median value of 1.9, range 0.4-5.6 micrograms/g creatinine, 12.5% of the cases having values a little greater than 5 micrograms/g creatinine) and among the residents in Carloforte (median value of 6.5, range 1.8-21.5 micrograms/g creatinine, 59.1% of the cases having values > 5 mcg/g creatinine). The HgU values observed in this group were in turn significantly higher than those of the non occupationally exposed workers living near Sassari (p = 0.03). Only in this last group were the HgU concentrations statistically significantly related to the extension of the amalgam fillings area (Pearson r = 0.53, p < 0.01). In the Carloforte group HgU was significantly related to the number of fish meal consumed per week (Pearson r = 0.48, p < 0.02). HgB (median value of 5.9, range 3.4-21.6 micrograms/l) as well as its inorganic component (median value of 2.4, range 1.8-4.6 micrograms/l) were significantly higher in the Chloralkali group compared to the other two groups. In all cases of the Carloforte group the ratio between the organic component and the total HgB was higher than 85%, while this ratio was significantly lower in the other two groups. The relationship between HgU and HgB was statistically significant, considering both total blood mercury and the inorganic and the organic components separately. A statistically significant relationship between the sea fish consumption per week and both total HgB (Pearson r = 0.82) and the organic component in this matrix (Pearson r = 0.84, p < 0.001) was observed among 16 non-occupationally exposed subjects. However, the significant relationship between organic blood mercury and sea fish consumption was almost entirely supported by the data observed in the Carloforte group. Total hair mercury levels analysed in 8 subjects of the Carloforte group were high (median value of 9.6, range 1.4-34.5 micrograms/g) and significantly related to sea fish consumption, and to both the individual Hg urinary excretion (Pearson r = 0.83) and to the organic component of blood mercury (Pearson r = 0.87). CONCLUSIONS: According to several experimental human and animal trials and to some recent studies on methylmercury toxicokinetic models, our results suggest that the organic compounds absorbed by usual sea fish consumption may be partially demethylated, increasing the inorganic Hg concentration in the kidney and consequently its urinary excretion, as was observed in the Carloforte group.


Assuntos
Indústria Química , Amálgama Dentário/farmacocinética , Comportamento Alimentar , Mercúrio/análise , Exposição Ocupacional , Alimentos Marinhos , Absorção , Adulto , Consumo de Bebidas Alcoólicas/epidemiologia , Animais , Biomarcadores , Bruxismo/epidemiologia , Goma de Mascar , Café , Creatinina/sangue , Exposição Ambiental , Feminino , Peixes , Contaminação de Alimentos , Cabelo/química , Humanos , Itália/epidemiologia , Estilo de Vida , Masculino , Mercúrio/sangue , Mercúrio/farmacocinética , Mercúrio/urina , Compostos de Metilmercúrio/farmacocinética , Pessoa de Meia-Idade , Octopodiformes , Fumar/epidemiologia , Inquéritos e Questionários
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