RESUMO
The study tested the hypothesis that certain pastoral forages and olive by-products, available in arid areas, may positively influence fatty acid composition and physicochemical properties of goat's milk. Thirty indigenous goats (body weight = 25.2 kg; age = 4.1 years) were allocated to three groups. During 60 days, the goats received ad libitum either dried olive leaves + Stipa tenacissima (group OL), khortane grass hay (group Ko) or oat hay (control diet, group OH). Milk samples were collected and analysed for total solids, fat, protein, lactose and ash content and fatty acid profile. Average milk yield did not statistically differ among groups. Milk total solids from OL group were higher in comparison with Ko and C groups (15.3, 14.7 and 14.5%, respectively; p < 0.05). Fat content was also higher for the OL group as compared to the other groups (5.44 vs. 5.01 and 4.66%, respectively, for Ko and OH). No significant differences were observed for the milk content of lactose, protein and ash. The percentage of saturated fatty acids of total milk fat was higher in OL and Ko groups compared to the C group (p < 0.001); the milk whereof was characterized by the highest percentage of monounsaturated (p < 0.01) and total unsaturated fatty acids. Milk fat of Ko and C groups showed significantly higher proportions of rumenic (CLA cis-9 trans-11) and vaccenic acids (C18:1 trans-11) compared to OL milk. The feeding system based on Stipa tenacissima and dried olive leaves resulted in the milk lowest proportion of trans-fatty acids and the highest proportion of polyunsaturated ω3-fatty acids (p < 0.05).
Assuntos
Ração Animal/análise , Dieta/veterinária , Ácidos Graxos/química , Cabras/fisiologia , Leite/química , Fenômenos Fisiológicos da Nutrição Animal , Animais , Clima Desértico , Ácidos Graxos/metabolismo , Feminino , Folhas de Planta/química , Plantas/química , Plantas/classificação , TunísiaRESUMO
Ricotta cheese, particularly the ovine type, is a typical Italian dairy product obtained by heat-coagulation of the proteins in whey. The aim of this work was to investigate the influence of whey protein concentration, obtained by ultrafiltration, on yield of fresh ovine ricotta cheese. Ricotta cheeses were obtained by thermocoagulation of mixtures with protein content of 1.56, 3.10, 4.16, and 7.09g/100g from the mixing of skim whey and ultrafiltered skim whey. A fat-to-protein ratio of 1.1 (wt/wt) was obtained for all mixtures by adding fresh cream. The initial mixtures, as well as the final ricotta cheeses, were analyzed for their composition and by SDS-PAGE. Protein bands were quantified by QuantityOne software (Bio-Rad, Hercules, CA) and identified by liquid chromatography-tandem mass spectrometry. Significant differences in the composition of the ricotta cheese were observed depending on protein concentration. Particularly, ricotta cheese resulting from the mixture containing 7.09g/100g of protein presented higher moisture (72.88±1.50g/100g) and protein (10.18±0.45g/100g) contents than that prepared from the mixture with 1.56g/100g of protein (69.52±1.75 and 6.70±0.85g/100g, respectively), and fat content was lower in this sample (12.20±1.60g/100g) compared with the other treatments, with mean values between 15.72 and 20.50g/100g. Each protein fraction presented a different behavior during thermocoagulation. In particular, the recovery of ß-lactoglobulin and α-lactalbumin in the cheese increased as their content increased in the mixtures. It was concluded that concentrating ovine rennet whey improved the extent of heat-induced protein aggregation during the thermal coagulation process. This resulted in a better recovery of each protein fraction in the product, and in a consequent increase of ricotta cheese yield.
Assuntos
Queijo/análise , Manipulação de Alimentos/métodos , Proteínas do Leite/química , Animais , Cromatografia Líquida , Quimosina/química , Gorduras na Dieta/análise , Proteínas Alimentares/análise , Eletroforese em Gel de Poliacrilamida , Temperatura Alta , Concentração de Íons de Hidrogênio , Lactalbumina/análise , Lactoglobulinas/análise , Proteômica , Ovinos , Espectrometria de Massas em Tandem , Ultrafiltração , Proteínas do Soro do LeiteRESUMO
PURPOSE: The objective of our study was to evaluate the presence of respiratory symptoms and chronic obstructive pulmonary disease (COPD) in a human immunodeficiency virus (HIV)-infected outpatient population and to further investigate the role of highly active antiretroviral therapy (HAART) and other possibly associated risk factors. METHODS: We consecutively enrolled in a cross-sectional study HIV-infected patients and HIV-negative age, sex and smoking status matched controls. All participants completed a questionnaire for pulmonary symptoms and underwent a complete spirometry. RESULTS: We enrolled 111 HIV-infected patients and 65 HIV-negative age- and sex-matched controls. HIV-infected patients had a significantly higher prevalence of any respiratory symptom (p = 0.002), cough (p = 0.006) and dyspnoea (p = 0.02). HIV-infected patients also had a significantly higher prevalence of COPD in respect of HIV-negative controls (p = 0.008). Furthermore, HIV-infected individuals had significantly (p = 0.002) lower forced expiratory volume at one second (FEV1) and FEV1/forced vital capacity (FVC) ratio (Tiffeneau index) (p = 0.028), whereas the total lung capacity (TLC) was significantly higher (p = 0.018). In the multivariate analysis, significant predictors of respiratory symptoms were current smoking [adjusted odds ratio (AOR) 11.18; 95 % confidence interval (CI) 3.89-32.12] and previous bacterial pneumonia (AOR 4.41; 95 % CI 1.13-17.13), whereas the only significant predictor of COPD was current smoking (AOR 5.94; 95 % CI 1.77-19.96). HAART receipt was not associated with respiratory symptoms nor with COPD. CONCLUSIONS: We evidenced a high prevalence of respiratory symptoms and COPD among HIV-infected patients. HIV infection, current cigarette smoking and previous bacterial pneumonia seem to play a significant role in the development of respiratory symptoms and COPD. Thus, our results suggest that the most at-risk HIV-infected patients should be screened for COPD to early identify those who may need specific treatment.
Assuntos
Terapia Antirretroviral de Alta Atividade , Infecções por HIV/epidemiologia , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Doença Pulmonar Obstrutiva Crônica/virologia , Adulto , Estudos de Casos e Controles , Comorbidade , Intervalos de Confiança , Estudos Transversais , Feminino , Volume Expiratório Forçado , Infecções por HIV/tratamento farmacológico , Inibidores da Protease de HIV/farmacologia , Humanos , Pulmão/patologia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Razão de Chances , Prevalência , Fatores de Risco , Ritonavir/farmacologia , Fumar/efeitos adversos , Espirometria , Inquéritos e Questionários , Capacidade Pulmonar TotalRESUMO
In the present study, the antibacterial property of the organophilic bentonite (Bent-ODA) and organophilic bentonite incorporated with geranyl acetate ester (Bent-ODA-GA) was evaluated against bacteria Staphylococcus aureus, Escherichia coli and Salmonella typhimurium. Oral acute toxicity of Bent-ODA-GA was evaluated in mice, by a single oral dose of 300 and 2000 mg kg-1. Animals were observed for any toxicity clinical signs or mortality for 15 days according to OECD 423 guidelines. The release assay of GA presents in Bent-ODA in simulated gastric fluid, pH 3.5 and pH 6.5 was also performed. Bent-ODA-GA composite presented antibacterial activity against S. aureus and S. typhimurium bacteria with 10.7 ± 0.6 mm and 2.2 ± 0.1 mm inhibition halo, respectively, which make it possible to associate the composite antimicrobial feature due to the ester presence. The composite did not reveal any toxicity signs or mortality in any animal for acute toxicity treatment during the 15 days observation period. The LD50 of Bent-ODA-DA was estimated to be greater than 2000 mg kg-1. It was also observed that geranyl acetate is released from Bent-ODA in concentrations lower than 0.03 mg kg-1 for pH 3.5 and 0.004 mg kg-1 for pH 6.5, which are lower than those that could cause some toxic effects in animals.
Assuntos
Anti-Infecciosos , Bentonita , Camundongos , Animais , Staphylococcus aureus , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Escherichia coli , BactériasRESUMO
OBJECTIVE: The advent of the SARS-CoV-2 pandemic has resulted in an increase in sedentary behavior, with consequences on cardiopulmonary capacity, especially in the elderly population. Prehabilitation is a strategy usually used before a surgical procedure to improve functional capacity; however, it can be used for non-surgical patients and not in the acute phase of disease. The purpose of this study is to evaluate the effectiveness of a prehabilitation program, using telerehabilitation, in frail elderly patients with chronic heart failure. PATIENTS AND METHODS: This is a randomized, controlled, single-blind study. Fifteen patients with chronic heart failure were randomized into three groups: two active groups (telerehabilitation and in-person) and the control group. Patients in the active groups underwent a rehabilitation program divided into two 4-week periods, for 45-60 minutes per day, 2 days per week. RESULTS: In the Study Group, the quality of life significantly improved (EQoL-5D), and between the two groups a statistically significant difference in the motor dimension of SF-36 was identified. CONCLUSIONS: The telerehabilitation prehabilitation program for patients with chronic heart failure was confirmed to be effective and not inferior to a prehabilitation program performed in-person, avoiding the worsening of some domains of quality of life and motor performance, and leading to the improvement of others.
Assuntos
COVID-19 , Insuficiência Cardíaca , Idoso , Humanos , Exercício Pré-Operatório , Qualidade de Vida , SARS-CoV-2 , Método Simples-CegoRESUMO
OBJECTIVE: Prehabilitation, intended as a multidisciplinary approach where physical training is combined with educational and counselling training, in cardiology could optimizing care, and has been shown to be able to reduce morbidity and mortality in several diseases. The present study aims to assess the effectiveness of a prehabilitation program in elderly patients (over 65) with chronic heart failure and to evaluate functional and quality indices of life. PATIENTS AND METHODS: This is randomized, single blind controlled trial. Fourteen older adult patients diagnosed with chronic heart failure were enrolled. Patients were randomly assigned into the study or the control group. Patients in the study group underwent physical training organized into 10 twice-weekly meetings, nutritional and lifestyle counseling. RESULTS: In the Study Group, the quality of life improved significantly (EQoL-5D), and between the two groups there is a statistically significant difference in the motor dimension of SF-36. CONCLUSIONS: Because of our preliminary results, prehabilitation program should be included among the management strategies of in elderly patients with chronic heart failure to better manage their disease and to improve their Quality of Life.
Assuntos
Insuficiência Cardíaca/terapia , Idoso , Idoso de 80 Anos ou mais , Doença Crônica , Terapia por Exercício , Feminino , Insuficiência Cardíaca/fisiopatologia , Humanos , Estilo de Vida , Masculino , Avaliação Nutricional , Terapia Nutricional , Educação de Pacientes como Assunto , Qualidade de Vida , Método Simples-Cego , Volume Sistólico , Resultado do TratamentoRESUMO
Eugenol is natural oil that has excellent antibacterial properties but cannot be used to fabricate many products that require thermal processing. One possible alternative to the use of the eugenol molecules in high-temperature processes is the encapsulation of these molecules in a structure that is not toxic and is resistant to thermal treatment. This work investigated the encapsulation process of eugenol molecules in ß-cyclodextrine and the antibacterial properties of eugenol-ß-cyclodextrine (the eugenol-ßCD complex) against Escherichia coli and Staphylococcus aureus. The FTIR, DSC, MEV and TGA results show that the encapsulation method is an excellent alternative to increase the thermal stability of eugenol molecules. A value of 241.32L.mol-1 was determined for the formation constant (Kc) of the eugenol-ßCD complex, which confirmed the success of the encapsulation process. The MEV analysis shows the formation of approximately 12µm microcapsules. After the thermal treatment of the eugenol-ßCD complex at a temperature of 80°C for 2h, the complex retained significant antibacterial action, which confirms the thermal protection of the eugenol molecules. The minimum inhibitory concentration (MIC) and agar diffusion results show that the microcapsules containing 17.08mmol.L-1 of eugenol exhibited excellent antibacterial action against Escherichia coli and Staphylococcus aureus after thermal treatment.
Assuntos
Antibacterianos , Escherichia coli/crescimento & desenvolvimento , Eugenol , Staphylococcus aureus/crescimento & desenvolvimento , beta-Ciclodextrinas , Antibacterianos/química , Antibacterianos/farmacologia , Cápsulas , Eugenol/química , Eugenol/farmacologia , beta-Ciclodextrinas/química , beta-Ciclodextrinas/farmacologiaRESUMO
The use of natural products as a diet supplement is increasing worldwide but sometimes is not followed by adequate sanitary controls and analyses. Twenty samples of pills and capsules of lyophilised cyanobacteria (blue-green algae), commercialised in Italy as dietary supplements, were found positive at the Vibrio fischeri bioassay. Further analyses with ELISA and LC-MS/MS methods revealed the presence of four microcystin (MC) analogues, MC-LR, -YR, -LA, -RR and two demethylated forms of MC-RR. The highest total microcystin content was 4.5 and 1.4 microg g-1 in pills and capsules, respectively. The ELISA measurements, compared to the LC-MS/MS analyses, showed significantly lower concentrations of microcystins in pills, this confirming a possible ELISA underestimate of mixed microcystins, due to different sensitivities for some toxic analogues.
Assuntos
Toxinas Bacterianas/análise , Cianobactérias/química , Suplementos Nutricionais/análise , Peptídeos Cíclicos/análise , Aliivibrio fischeri/crescimento & desenvolvimento , Animais , Ensaio de Imunoadsorção Enzimática , Cromatografia Gasosa-Espectrometria de Massas , Toxinas Marinhas , MicrocistinasRESUMO
The effect of ganglioside administration to nondiabetic and streptozocin-induced diabetic rats on sciatic nerve Na(+)-K(+)-ATPase, polyphosphoinositide (PPI) turnover, and protein phosphorylation was investigated. Gangliosides were injected (10 mg/kg body wt i.p.) for 10 or 30 days beginning 20 days after induction of diabetes. Na(+)-K(+)-ATPase activity was reduced nearly 50% in diabetic nerve and was restored to normal by both ganglioside treatments. The elevated levels of fructose and sorbitol and depressed content of myoinositol in diabetic nerve were unaffected by 30 days of ganglioside treatment, indicating that the restoration of Na(+)-K(+)-ATPase activity is not dependent on normal concentrations of these compounds. In the same nerves, 32P incorporation into phosphatidylinositol 4,5-bisphosphate and phosphatidylinositol 4-phosphate increased 73-76 and 39-53%, respectively, in diabetic compared with nondiabetic tissue. Ganglioside administration abolished the elevated labeling of PPIs after 30 days but was ineffective after only 10 days. Neither ganglioside regimen was able to reverse enhanced phosphorylation of the major peripheral nerve myelin protein P0. The finding that gangliosides can more quickly correct the effects of diabetes on Na(+)-K(+)-ATPase activity than on PPI turnover suggests that the mechanisms underlying these two phenomena are not closely related and are distinct from the sequence of events responsible for altered myelin protein phosphorylation.
Assuntos
Diabetes Mellitus Experimental/metabolismo , Gangliosídeos/farmacologia , Fosfolipídeos/metabolismo , Nervo Isquiático/metabolismo , Animais , Frutose/metabolismo , Inositol/metabolismo , Masculino , Proteínas da Mielina/biossíntese , Ouabaína/farmacologia , Fosfatidilinositóis/biossíntese , Ratos , Ratos Endogâmicos , Valores de Referência , Nervo Isquiático/efeitos dos fármacos , ATPase Trocadora de Sódio-Potássio/metabolismo , Sorbitol/metabolismoRESUMO
ATPase activities were measured in sciatic nerves from rats with alloxan-induced diabetes (ALX-D) of various duration (2 wk, 5 wk, 9 wk, and 6 mo). Our data confirm that sciatic nerve Na+-K+-ATPase abnormalities are present very early in ALX-D rats, similar to results previously described in streptozocin-induced diabetic rats, spontaneously diabetic BB Wistar rats, and ALX-D rabbits. Na+-K+-ATPase activity decreased by 26-47% in ALX-D rats compared with age-matched controls. Ganglioside treatment (10 mg/kg i.p. for 10 or 30 days starting 1 wk after ALX injection) completely impeded the enzyme reduction. The effect observed at the end of either 10 or 30 days of treatment lasted greater than or equal to 1 mo. Chronic diabetic groups treated for 30 days before killing also presented normal ATPase activity at the end of treatment. Therefore, gangliosides are effective on Na+-K+-ATPase even in animals with a longer duration of diabetes. The maintenance of fairly normal ATPase activity by ganglioside treatment could mirror a more general recovery from early metabolic dysfunction and/or late structural abnormalities in diabetic nerve fibers.
Assuntos
Diabetes Mellitus Experimental/enzimologia , Gangliosídeos/farmacologia , Nervo Isquiático/enzimologia , ATPase Trocadora de Sódio-Potássio/deficiência , Aloxano , Animais , Diabetes Mellitus Experimental/tratamento farmacológico , Masculino , Ratos , ATPase Trocadora de Sódio-Potássio/metabolismoRESUMO
Abnormalities in axonal transport of proteins are thought to play an important role in the pathogenesis of diabetic neuropathy. Gangliosides exert a positive action on numerous alterations in biochemistry and physiology of diabetic nerves. This study was undertaken to assess the effects of exogenous gangliosides on the axonal transport of structural proteins such as actin and tubulin in the sensory fibers of short-term (9-wk) and long-term (6-mo) diabetic rats. Adult Sprague-Dawley rats were made diabetic with a single injection of 70 mg/kg streptozocin i.p. Subgroups were injected daily with either highly purified ganglioside mixture (10 mg/kg i.p.) or saline for 1 mo, beginning either 2 or 17 wk after streptozocin injection. Age-matched rats were used as controls. Axonal transport was studied by the pulse-labeling technique. Three weeks after labeling, sciatic nerves were dissected out and processed for sodium dodecyl sulfate-polyacrylamide gel electrophoresis and fluorography. In diabetic rats of both experimental designs, the transport rate of tubulin and actin was decreased by approximately 30% compared with control rats. Ganglioside treatment counteracted such alterations in both 9-wk and 6-mo diabetic rats. These data suggest a pharmacological effect that could be correlated with molecular interactions between integral membrane glycolipids and cytoskeletal elements.
Assuntos
Transporte Axonal/efeitos dos fármacos , Proteínas do Citoesqueleto/metabolismo , Diabetes Mellitus Experimental/fisiopatologia , Neuropatias Diabéticas/fisiopatologia , Gânglios Espinais/fisiopatologia , Gangliosídeos/farmacologia , Proteínas de Neurofilamentos/metabolismo , Nervo Isquiático/fisiopatologia , Actinas/metabolismo , Animais , Glicemia/metabolismo , Eletroforese em Gel de Poliacrilamida , Gânglios Espinais/efeitos dos fármacos , Gânglios Espinais/fisiologia , Hemoglobinas Glicadas/análise , Masculino , Proteínas de Neurofilamentos/isolamento & purificação , Ratos , Ratos Endogâmicos , Valores de Referência , Nervo Isquiático/efeitos dos fármacos , Nervo Isquiático/fisiologia , Tubulina (Proteína)/metabolismoRESUMO
The efficacy of gangliosides in enhancing axonal regeneration and maturation in the early stages of diabetic neuropathy was assessed by quantitative analysis of immunostained serial sections of the sciatic nerve. Sprague-Dawley rats were made diabetic with a single injection of alloxan (100 mg/kg). One week later they were injected daily intraperitoneally with either a highly purified ganglioside mixture (10 mg/kg) or sterile saline for 4 wk. At the end of the treatment, sciatic nerves were crushed and allowed to regenerate for 1 wk without ganglioside treatment. The animals were then killed, and the nerves were frozen and processed for immunohistochemistry and electron microscopy. The number of regrowing axons was counted with a computerized image-analysis system on cross sections taken at predefined distances along the regenerating stump and stained with monoclonal antibody iC8 specific for the 145,000-Mr subunit of the neurofilaments. In untreated diabetic animals the number of axons able to regenerate and sustain elongation for greater than or equal to 13 mm from the crush point was reduced by 40% with respect to control rats. Ganglioside treatment was effective in compensating almost completely for this dramatic reduction. Electron microscopy confirmed that the immunofluorescence counts corresponded to regenerating axons containing neurofilaments. These results suggest that gangliosides are able to compensate for the derangements of axonal transport of cytoskeletal proteins reported in experimental diabetic neuropathy.
Assuntos
Axônios/fisiologia , Diabetes Mellitus Experimental/tratamento farmacológico , Neuropatias Diabéticas/tratamento farmacológico , Gangliosídeos/uso terapêutico , Regeneração Nervosa/efeitos dos fármacos , Aloxano , Animais , Anticorpos Monoclonais , Axônios/metabolismo , Axônios/ultraestrutura , Glicemia/análise , Peso Corporal , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/fisiopatologia , Neuropatias Diabéticas/metabolismo , Neuropatias Diabéticas/fisiopatologia , Imunofluorescência , Processamento de Imagem Assistida por Computador , Immunoblotting , Imuno-Histoquímica , Filamentos Intermediários/metabolismo , Filamentos Intermediários/ultraestrutura , Masculino , Microscopia Eletrônica , Ratos , Ratos Endogâmicos , Nervo Isquiático/metabolismo , Nervo Isquiático/fisiopatologia , Nervo Isquiático/ultraestruturaRESUMO
The authors report the case of a man with acquired immune deficiency syndrome (AIDS) who was admitted to the hospital because of an organic mental syndrome with affective and delusional features.
Assuntos
Síndrome da Imunodeficiência Adquirida/complicações , Transtornos Neurocognitivos/complicações , Síndrome da Imunodeficiência Adquirida/psicologia , Adulto , Delusões/complicações , Delusões/psicologia , Hospitalização , Humanos , Masculino , Transtornos Neurocognitivos/psicologiaRESUMO
To assess the effects of monosialoganglioside GM1 on some immunological parameters, 12 healthy men were treated with 100 mg GM1 i.m. daily for 15 days. Before and after treatment, the following were studied: (1) serum levels of antibodies against GM1, asialo-GM1 (aGM1), GM2 and GD1b; (2) serum levels of interleukin (IL)-1 beta, IL-2, soluble IL-2 receptor (sIL-2R), tumor necrosis factor-alpha (TNF-alpha), and interferon-gamma (IFN-gamma); (3) IL-1 beta and TNF-alpha production by peripheral blood monocytes (PBMO). Anti-ganglioside antibody and cytokine serum levels were not affected by exogenous GM1 administration with the exception of a transient increase in anti-GM1 antibody titer observed in one subject. In addition, no inhibition of IL-1 beta and TNF-alpha production by PBMO was observed. These preliminary data do not support a potential immunogenic or immunomodulatory function for in vivo administered GM1.
Assuntos
Anticorpos/análise , Citocinas/sangue , Gangliosídeo G(M1)/farmacologia , Gangliosídeos/imunologia , Adolescente , Adulto , Cromatografia em Camada Fina , Ensaio de Imunoadsorção Enzimática , Humanos , Infusões Parenterais , Valores de ReferênciaRESUMO
The diagnosis of depression has traditionally been based on clinical history and behavioral observations. While objective laboratory tests will further our understanding of the pathophysiology and perhaps aid in the management of depression, a critical examination of the application of these techniques in clinical psychiatry is warranted by their increasing use. The utility for clinicians of the dexamethasone suppression test (DST), urinary MHPG assay, and tricyclic antidepressant plasma level assay is reviewed.
Assuntos
Transtorno Depressivo/diagnóstico , Dexametasona , Glicóis/urina , Metoxi-Hidroxifenilglicol/urina , Adolescente , Adulto , Antidepressivos Tricíclicos/sangue , Criança , Transtorno Depressivo/fisiopatologia , Transtorno Depressivo/urina , Humanos , Hidrocortisona/sangue , Sistema Hipotálamo-Hipofisário/fisiopatologia , Norepinefrina/fisiologia , Sistema Hipófise-Suprarrenal/fisiopatologiaRESUMO
RATIONALE AND OBJECTIVES: The use of the newest nonionic, water-soluble, low-osmolar radiographic contrast media (CM) is still associated with occasional adverse reactions affecting the neural tissues. Because these CM display lipophilic potential in their interactions with biological membranes when diffusing within the brain parenchyma, they could affect neurotransmitter binding to the receptors. Two representative nonionic CM, iopamidol and iohexol, were studied to assess whether CM-related neurotoxicity derived from their interactions with specific receptors on neural membranes. METHODS: Binding assays were carried out in vitro on crude total membrane or crude synaptic membrane preparations from selected brain areas (cortex, striatum, hippocampus, cerebellum). The concentrations of CM and reference drugs that reduce specific binding of each ligand by 50% of its maximum value (IC50) were determined using radioligands to the receptors of the most common neurotransmitters in the central nervous system, including excitatory amino acids. RESULTS: Neither iopamidol nor iohexol inhibited the (3H) ligand binding to any kind of receptor up to very high concentrations (100 microM). CONCLUSIONS: The nonionic, low-osmolar CM did not influence the normal functions of neural membranes in our model. This suggests that occasional neurotoxic effects do not occur as a consequence of specific action on brain receptors. These CM may have an indirect, postmembrane site of action.
Assuntos
Encéfalo/efeitos dos fármacos , Iohexol/toxicidade , Iopamidol/toxicidade , Animais , Ligação Competitiva , Encéfalo/metabolismo , Iohexol/metabolismo , Iopamidol/metabolismo , Masculino , Concentração Osmolar , Ensaio Radioligante , Ratos , Ratos Sprague-Dawley , Receptores de Neurotransmissores/metabolismoRESUMO
Spinal cords of cats treated with the neurotoxic compound beta,beta'-iminodipropionitrile (IDPN) were observed to contain rounded homogeneous bodies, 1-12 microns in diameter, termed "dense microspheres" (DMS). These bodies, absent in control animals, were consistently found only in the ventral horns. No relationship with blood vessels was evident. When stained with PAS and a modified von Kossa's silver nitrate technique, DMS remained negative, showing only very slight metachromasia in some toluidine blue-stained sections. They were consistently acidophilic as evidenced by destaining and differentiation investigations. DMS were observed more frequently in the proximity of nerve cell bodies or closely adjacent to dendrites and their location was mainly extracytoplasmic; with the electron microscope, however, some DMS were also found in glial processes. Rounded osmiophilic bodies, 0.1-0.8 microns in diameter, were noticed in mitochondria of both neurons and glial cells; however, whether they were special forms of DMS or different inclusions was not assessed. Both intra- and extracytoplasmic DMS were similar in ultrastructure, appearing as single membrane-bound spherical or pear-shaped bodies containing a cottony or finely granular matrix. Additionally, both perikaryon and processes of large motoneurons were found to contain pigment granules identified as lipofuscin, which seemed to increase in number and to spread centrifugally in the processes in correlation with duration of the intoxication and size of axonal swellings induced by IDPN.(ABSTRACT TRUNCATED AT 250 WORDS)
Assuntos
Nitrilas/toxicidade , Medula Espinal/efeitos dos fármacos , Animais , Gatos , Grânulos Citoplasmáticos/ultraestrutura , Feminino , Lipofuscina/metabolismo , Masculino , Microscopia Eletrônica , Medula Espinal/metabolismo , Medula Espinal/ultraestruturaRESUMO
Vincristine (VCR) administration to rabbits resulted in severe electrophysiologic alterations of peripheral nerves. Sciatic nerve conduction velocity, compound action potential (CAP) amplitude, and area under the CAP waveform were all reduced in a dose-dependent fashion. In addition, the pattern of conduction velocity of both motor and sensory fibers was altered and shifted toward slow conduction classes. Simultaneous treatment with gangliosides limited significantly the changes in electrophysiologic parameters induced by VCR. It is suggested that gangliosides be given in the clinical setting as protection for the peripheral nerves against the side effects of antiblastic therapy.
Assuntos
Gangliosídeos/farmacologia , Músculos/efeitos dos fármacos , Nervos Periféricos/efeitos dos fármacos , Vincristina/toxicidade , Potenciais de Ação/efeitos dos fármacos , Animais , Antagonismo de Drogas , Eletrofisiologia , Masculino , Músculos/inervação , Condução Nervosa/efeitos dos fármacos , Coelhos , Nervo Isquiático/efeitos dos fármacosRESUMO
We applied a three-component (temporal, occipital and parietal) spatial model to EEG data obtained from 46 young and 11 elderly subjects. With closed eyes the mean alpha frequency was 9.51 Hz for the temporal, 9.88 Hz for the occipital and 10.14 Hz for the parietal component. The power of the occipital component was larger than that of the others. With open eyes it was reduced to the same level as the temporal and parietal components. The power of the occipital component decreased significantly with age.
Assuntos
Envelhecimento/fisiologia , Ritmo alfa , Mapeamento Encefálico , Córtex Cerebral/fisiologia , Adulto , Idoso , Análise de Variância , Feminino , Humanos , Masculino , Lobo Occipital/fisiologia , Lobo Parietal/fisiologia , Valores de Referência , Lobo Temporal/fisiologiaRESUMO
Spinal cord patterns of metabolic activity in a model of neuropathic pain were assessed in unanesthetized rats by the [14C]-2-deoxyglucose (2-DG) technique. Rats used in this procedure had demonstrable thermal hyperalgesia ipsilateral to sciatic nerve ligation and ipsilateral hindpaws that were lifted in a guarded position. The latter indicated possible spontaneous pain. Sciatic nerve ligation produced significant increases in glucose utilization in the dorsal and ventral horns of both sides, with greater activity present on the ipsilateral as compared to the contralateral side. Peak activity was in laminae V-VI, a region involved in nociceptive processing. Thus, a chronic increase in neuronal activity in these regions may reflect spontaneous neuropathic pain.