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1.
Mult Scler Relat Disord ; 53: 103036, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34051695

RESUMO

Upper limbs (UL) dysfunction is frequent in people with Multiple Sclerosis (PwMS). Several objective measures of UL function are proposed; however, their use is mostly confined to assess subjects with mild-to-moderate disability and requires fine motor skills, often impaired in high disability level subjects. Thus, a tool to score UL function in the advanced disease stage is lacking. The aim of the study is to analyse and compare UL unilateral and bilateral movements of healthy control (HC) and PwMS, at different disability levels, using an instrumented version (Inertial Measurement Unit, IMU) of the 15-seconds finger-to-nose test (FNT). Each movement cycle was segmented in going/adjusting/returning phases. The inter-hand interval (IHI) allowed assessing bilateral coordination (i.e. synchrony) in each phase. The larger IHI, the more severe the bilateral coordination impairment is. After stratifying PwMS for disability level (PwMSLOW, Expanded Disability Status Scale, EDSS≤5.5 and PwMSHIGH, EDSS≥6), the ANOVA on IHI showed significant differences between PwMS and HC (p<0.001) in all phases. However, only the going phase IHI showed significantly higher asynchrony in PwMSHIGH than PwMSLOW and HC (p<0.001) and no differences between PwMSLOW and HC. The going phase IHI seems to be a clinical marker specific for high disability level PwMS. These findings suggest inertial sensors during FNT could be an easy-to-use method for a more detailed quantitative characterization of UL function in PwMS also in subjects with EDSS greater than 6.


Assuntos
Pessoas com Deficiência , Esclerose Múltipla , Mãos , Humanos , Movimento , Extremidade Superior
2.
Mult Scler Relat Disord ; 45: 102422, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32731199

RESUMO

BACKGROUND: The Expanded Disability Status Scale (EDSS) is the most frequently used scale to measure neurologic impairment and quantify the level of disability in Multiple Sclerosis (MS) even though the scale focuses on ambulation and undervalues upper limb (UL) impairment. The 9-Hole Peg Test (9-HPT) is the gold standard for UL assessment in MS, calculating a mean score from right and left arms, even though subjects with MS often show a lateralization of neurological deficit. OBJECTIVE: The study aimed to determine whether an interaction exists between mean right-left 9-HPT scores or 9HPT score asymmetry (difference between right and left side) in predicting EDSS in MS subjects. METHODS: Demographic and disease variables and 9-HPT scores were obtained from medical records of individuals with MS collected in an ad-hoc database. Subjects with 9-HPT score ≤180 s for each arm were included. An asymmetry score was represented as the absolute value of the difference between 9-HPT scores for both arms. RESULTS: 549 subjects were included: 67.8% female, mean age 45±13.14 years, mean EDSS 3.98±2.12, 356 relapsing-remitting, 68 primary and 125 secondary progressive, mean 9-HPT scores: right arm 30.20 ± 19.99 s, left arm 31.80 ± 20.35 s. Mean asymmetry was 9.35±18.20 s. Correlation between mean right-left 9-HPT scores and EDSS was 0.58 (p<.001). Significant interaction between mean right-left 9-HPT scores and 9-HPT asymmetry in predicting EDSS scores was found. Regression slope of EDSS on mean right-left 9-HPT score decreases as asymmetry value increases (non-significance area values ≥ 40.93 s). CONCLUSIONS: Findings suggest interaction exists between mean right-left 9-HPT scores and asymmetry in predicting EDSS. A consequence of this is that, by disregarding information about asymmetry, studies exploring the association between mean right-left 9-HPT scores and global measures of disability may provide biased results. The bias tends to increase as asymmetry increases, and to be most prevalent among patients with EDSS scores > 6.


Assuntos
Pessoas com Deficiência , Esclerose Múltipla , Adulto , Avaliação da Deficiência , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/diagnóstico , Extremidade Superior , Caminhada
3.
Eur J Neurol ; 27(12): 2523-2530, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32619066

RESUMO

BACKGROUND AND PURPOSE: Limited data are available in the literature for upper limb impairment in multiple sclerosis (MS). This study aimed to report the distribution of values of hand grip strength (HGS), of the box and block test (BBT) and of the nine-hole peg test (9HPT) correlated with demographic and clinical data in subjects with MS. METHODS: This study involved five Italian neurological centres. The inclusion criteria were age ≥ 18, MS diagnosis, stable disease phase, right-hand dominance. All subjects underwent HGS, BBT and 9-HPT evaluation. RESULTS: In all, 202 subjects with MS were enrolled: 137 females; mean age 48.4 years; mean Expanded Disability Status Scale (EDSS) 4.17; mean disease duration 14.12 years; disease course 129 relapsing-remitting, 21 primary progressive and 52 secondary progressive MS subjects; mean right HGS 25.3 kg, left 23.2 kg; mean right BBT 45.7 blocks, left 44.9 blocks; mean right 9-HPT 30.7 s, left 33.4 s. All results were statistically significantly different compared to healthy controls. HGS, BBT and 9-HPT were associated with age, EDSS and disease duration, whilst disease course correlated with BBT and 9-HPT. The BBT and 9-HPT scores significantly differed according to level of disability (EDSS ≤3.0, 3.5-5.5, ≥6.0). CONCLUSION: Hand grip strength and BBT value distribution in a large MS population is reported. Correlations between HGS, BBT and 9-HPT were generally low.


Assuntos
Esclerose Múltipla , Avaliação da Deficiência , Feminino , Força da Mão , Humanos , Itália , Pessoa de Meia-Idade , Esclerose Múltipla/diagnóstico , Extremidade Superior
4.
Anal Bioanal Chem ; 412(15): 3595-3604, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32248395

RESUMO

The detection of Salmonella spp. in food samples is regulated by the ISO 6579:2002 standard, which requires that precise procedures are followed to ensure the reliability of the detection process. This standard requires buffered peptone water as a rich medium for the enrichment of bacteria. However, the effects of different brands of buffered peptone water on the identification of microorganisms by Raman spectroscopy are unknown. In this regard, our study evaluated the discrimination between two bacterial species, Salmonella enterica and Escherichia coli, inoculated and analyzed with six of the most commonly used buffered peptone water brands. The results showed that bacterial cells behaved differently according to the brand used in terms of biomass production and the spectral fingerprint. The identification accuracy of the analyzed strains was between 85% and 100% depending on the given brand. Several batches of two brands were studied to evaluate the classification rates between the analyzed bacterial species. The chemical analysis performed on these brands showed that the nutrient content was slightly different and probably explained the observed effects. On the basis of these results, Raman spectroscopy operators are encouraged to select an adequate culture medium and continue its use throughout the identification process to guarantee optimal recognition of the microorganism of interest.


Assuntos
Escherichia coli/isolamento & purificação , Salmonella enterica/isolamento & purificação , Análise Espectral Raman/métodos , Técnicas de Tipagem Bacteriana/métodos , Soluções Tampão , Escherichia coli/química , Infecções por Escherichia coli/microbiologia , Humanos , Peptonas/análise , Salmonella enterica/química , Água/análise
5.
Sci Total Environ ; 568: 770-784, 2016 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-27169730

RESUMO

MERLIN-Expo is a library of models that was developed in the frame of the FP7 EU project 4FUN in order to provide an integrated assessment tool for state-of-the-art exposure assessment for environment, biota and humans, allowing the detection of scientific uncertainties at each step of the exposure process. This paper describes the main features of the MERLIN-Expo tool. The main challenges in exposure modelling that MERLIN-Expo has tackled are: (i) the integration of multimedia (MM) models simulating the fate of chemicals in environmental media, and of physiologically based pharmacokinetic (PBPK) models simulating the fate of chemicals in human body. MERLIN-Expo thus allows the determination of internal effective chemical concentrations; (ii) the incorporation of a set of functionalities for uncertainty/sensitivity analysis, from screening to variance-based approaches. The availability of such tools for uncertainty and sensitivity analysis aimed to facilitate the incorporation of such issues in future decision making; (iii) the integration of human and wildlife biota targets with common fate modelling in the environment. MERLIN-Expo is composed of a library of fate models dedicated to non biological receptor media (surface waters, soils, outdoor air), biological media of concern for humans (several cultivated crops, mammals, milk, fish), as well as wildlife biota (primary producers in rivers, invertebrates, fish) and humans. These models can be linked together to create flexible scenarios relevant for both human and wildlife biota exposure. Standardized documentation for each model and training material were prepared to support an accurate use of the tool by end-users. One of the objectives of the 4FUN project was also to increase the confidence in the applicability of the MERLIN-Expo tool through targeted realistic case studies. In particular, we aimed at demonstrating the feasibility of building complex realistic exposure scenarios and the accuracy of the modelling predictions through a comparison with actual measurements.


Assuntos
Exposição Ambiental/análise , Poluentes Ambientais/análise , Poluentes Ambientais/farmacocinética , Modelos Biológicos , Compostos Orgânicos/análise , Compostos Orgânicos/farmacocinética , Animais , Biota/fisiologia , Produtos Agrícolas/química , Exposição Ambiental/estatística & dados numéricos , Europa (Continente) , Água Doce/química , Humanos , Leite/química , Multimídia , Valor Preditivo dos Testes , Medição de Risco , Incerteza
6.
Pediatr Surg Int ; 29(12): 1287-91, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23887770

RESUMO

UNLABELLED: Anorectal malformation (ARM) is a group of significant birth defects with geographic variation in incidence, individual phenotypes and regional geographic subtypes occurring in approximately 1:5,000 live births. Anorectal atresia with gross terminal colonic distension in the presence of an absent anal canal has also been known as 'pouch colon' which is mainly associated with the Indian subcontinent. Its prevalence is unknown but it is rare, possibly representing a fraction of 1 % of ARM. The problem seems to revolve around the gross terminal distension of the distal pouch which remains a significant surgical challenge to surgeons resulting in poorer postoperative continence in many instances. AIM: This study set out to collate data on ARM patients with gross terminal distension of the distal pouch from Africa to evaluate its epidemiology and outcome in African patients. METHODS: Fifteen African paediatric surgical centres (7 South African and 8 African centres) were polled on the occurrence of anorectal atresia with gross terminal distension of the terminal bowel, an ARM variant. Data included ethnic group, age, gender as well as the anatomical pathology, classification and presence or absence of associated anomalies. RESULTS: Of 12 respondents, 8 (67 %) responded and sufficient data to classify and analyse were obtained from six of the eight positive replies (7 new cases). Abdominal X-ray showed a grossly dilated terminal portion of the colon in the presence of an imperforate anus. A colovesical fistula was observed in four (three males and one female cloaca). Three were associated with a colonic atresia, of which two were in the transverse colon and one in the sigmoid colon. Surgical corrective procedures were carried out in six, but one patient, with a cloaca, died prior to surgical correction. CONCLUSIONS: In this survey of 15 African centres, we have attempted to document the occurrence and presentation of anorectal atresia with gross terminal distension in Africa and report seven additional new cases. A possible association with associated conditions like colonic atresia requires further investigation.


Assuntos
Anormalidades Múltiplas/cirurgia , Anus Imperfurado/cirurgia , Anormalidades Múltiplas/diagnóstico por imagem , África , Canal Anal/anormalidades , Canal Anal/diagnóstico por imagem , Canal Anal/cirurgia , Malformações Anorretais , Anus Imperfurado/diagnóstico por imagem , Colostomia/métodos , Dilatação Patológica , Feminino , Humanos , Recém-Nascido , Masculino , Reto/anormalidades , Reto/diagnóstico por imagem , Reto/cirurgia , Tomografia Computadorizada por Raios X/métodos
7.
J Infect Dis ; 202 Suppl: S156-61, 2010 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-20684696

RESUMO

BACKGROUND: Intussusception is a common gastrointestinal emergency in children and appears to have a somewhat different clinical spectrum in developing countries. Its etiology is still unclear, but a link to infective agents and viruses has been highlighted. This study aimed to assess the clinical spectrum and prevalence of intussusception in children from the diverse South African population. METHODS: Retrospective data were obtained from 9 participating pediatric referral units on the occurrence of intussusception in South African children (<14 years old) during a 6-year period (1998-2003). Results were correlated with national population statistics. Intussusception was anatomically classified into ileoileal, ileocolic, and colocolic types. The clinical features, management, outcome, and possible causes were examined. RESULTS: We reviewed the occurrence and clinical spectrum of intussusception in 423 children (age, 0-14 years) presenting with acute intussusception to 9 pediatric surgical centers. The mean duration of symptoms was 1.5 days, but a delayed presentation was common (median delay, 2.3 days). Intussusception occurred throughout the year, with a peak in the summer months. The majority of patients (89%) were <2 years old, and 78% presented at age 3-18 months of age. Crude population estimates indicate an occurrence of 1 case per 3123 population <2 years old. Only 11% of patients presented after 2 years of age, and the age at presentation was significantly lower (P < .05) in black African patients. All ethnic groups were affected. In 84% of patients, intussusception occurred at the ileocolic region junction, in 7% it was ileoileal, and in 9% it was colocolic. Colocolic intussusception appeared more common in black African patients, and associated pathologic conditions (polyps and Burkitt's lymphoma) occurred mainly in older children. Surgical intervention was required in 81% of patients and involved resection of gangrenous bowel in 40%. CONCLUSION: Intussusception appears to be a relatively frequent occurrence in children in South Africa. Although the clinical spectrum appears to vary, there is an apparent link to intestinal infection, which requires further investigation. A collaborative approach is required to ascertain the relationship of intussusception to preventable infections and to improve its diagnosis and management.


Assuntos
Intussuscepção/epidemiologia , Adolescente , Distribuição por Idade , Criança , Pré-Escolar , Enema/estatística & dados numéricos , Hospitais Pediátricos/estatística & dados numéricos , Humanos , Lactente , Recém-Nascido , Intussuscepção/cirurgia , Prevalência , Estudos Retrospectivos , Estações do Ano , África do Sul/epidemiologia , Resultado do Tratamento
8.
Gynecol Obstet Fertil ; 36(7-8): 767-72, 2008.
Artigo em Francês | MEDLINE | ID: mdl-18586546

RESUMO

OBJECTIVES: Since we observed in our laboratory a significant decrease of the fertilization rate in the classical IVF procedure compared to ICSI, we wanted to evaluate a new insemination procedure, using sperm morphology of selected semen as a criterion taken into account to calculate the number of mobile sperm to inseminate. PATIENTS AND METHODS: Therefore, we designed a prospective autocontrolled study which took place from September 2006 to May 2007. All IVF attempts resulting from infertile couples were included in the study if a previous analysis (lesser than one year) of sperm parameters performed in our laboratory was assessed as normal. The retrieved oocytes were separated into two groups (sibling ovocytes), inseminated randomly either with the usual procedure (control group) or with the tested protocol (tested group). Fertilization rate was the primary end point to evaluate this assay. Polyspermy rates were also compared. Subsequently, embryonic quality and development were assessed to eliminate an oxidative stress impact. Paired Student t-test was applied for statistical analysis. RESULTS: In all, 130 couples were included. The diploid fertilization rate was significantly increased in the tested group compared to the control group (66.9% vs 61.3%; p=0.017). No statistically significant difference was showed between the polyspermy rate and numbers of (i) good quality embryos and (ii) blastomeres per embryo into the two groups. DISCUSSION AND CONCLUSION: Compared with the conventional insemination procedure, the fertilization rate benefited from the tested insemination method in our laboratory without damaging embryonic growth. In the limit of our procedure, selected sperm morphology should be used to inseminate an appropriate number of spermatozoa within oocytes, even in case of normal semen values.


Assuntos
Implantação do Embrião/fisiologia , Fertilização in vitro/métodos , Inseminação Artificial/métodos , Oócitos/citologia , Oócitos/fisiologia , Espermatozoides/citologia , Espermatozoides/fisiologia , Feminino , Humanos , Recém-Nascido , Masculino , Recuperação de Oócitos , Gravidez , Estudos Prospectivos , Irmãos
9.
Acta bioquím. clín. latinoam ; 40(2): 265-268, jun. 2006. tab, graf
Artigo em Espanhol | LILACS | ID: lil-508469

RESUMO

Las disferritinemias se observan frecuentemente en el laboratorio de análisis clínicos. Se describen los principales exámenes etiológicos. La hipoferritinemia esencialmente manifista una carencia marcial. En la práctica habitual, la hiperferritinemia puede ser de origen inflamatorio, citolítico (cánceres, síndrome metabólico, hepatopatías, hemólisis) o poner de manifiesto sobrecargas de hierro secundarias o primarias (tranfusiones, anomalías de la hemoglobina, hemocromatosis).


Assuntos
Humanos , Algoritmos , Ferritinas , Ferritinas/deficiência , Receptores da Transferrina/sangue
10.
Niger Postgrad Med J ; 11(1): 26-31, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15254568

RESUMO

BACKGROUND: Contrary to our local experience, published data elsewhere show increased survival rates from major burns due to improvements in management. This study aimed at examining problems of burns management in children. DESIGN: Relevant data extracted from the records of 44 children included sociodemographic, clinical, management characteristics and outcomes. RESULTS: There were 86.0% thermal burns due to accidental, domiciliary events in 36 (81.8%. Mean (range) BSA was 35.9% +/- 4.0 (1%-95%), mostly 2nd degree burns in 34 (77.3%). Mean (range) duration of symptoms before presentation was 1.1 +/- 0.3 days (1-7 days). Following hospitalisation, involvement of key experts in acute burns care was either delayed or omitted. Intensive care monitoring and support including mechanical ventilation were unavailable for 11 (25.0%) cases with cardiorespiratory compromise. Septicaemia & pneumonias were associated with death in 9 (56.3%) of the 16 deaths. Klebsiella, pseudomonas and coliform organisms were isolated from most burns wound. Oral acetominophen and intramuscular dipyrone were the main analgesics used in 24 (54.6%) and 8 (18.2%) cases respectively. Anxiolytics were used in only 2 94.5%). Case fatality rate was 36.4%. Mortalities were 100% with BSA 50-100% (p=0. 000). CONCLUSION: Prevention and improvements in management of burns including early multidisciplinary care, critical care support, aggressive wound care and adequate pain control should be emphasised.


Assuntos
Queimaduras/terapia , Avaliação de Processos e Resultados em Cuidados de Saúde , Adolescente , Queimaduras/complicações , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Escala de Gravidade do Ferimento , Tempo de Internação , Masculino , Nigéria , Estudos Retrospectivos , Fatores Socioeconômicos
11.
Neurochem Res ; 24(3): 399-406, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10215514

RESUMO

Using a method and model developed in our laboratory to quantitatively study brain phospholipid metabolism, in vivo rates of incorporation and turnover of docosahexaenoic acid in brain phospholipids were measured in awake rats. The results suggest that docosahexaenoate incorporation and turnover in brain phospholipids are more rapid than previously assumed and that this rapid turnover dilutes tracer specific activity in brain docoshexaenoyl-CoA pool due to release and recycling of unlabeled fatty acid from phospholipid metabolism. Fractional turnover rates for docosahexaenoate within phosphatidylinositol, choline glycerophospholipids, ethanolamine glycerophospholipids and phosphatidylserine were 17.7, 3.1, 1.2, and 0.2 %.h(-1), respectively. Chronic lithium treatment, at a brain level considered to be therapeutic in humans (0.6 micromol.g(-1)), had no effect on turnover of docosahexaenoic acid in individual brain phospholipids. Consistent with previous studies from our laboratory that chronic lithium decreased the turnover of arachidonic acid within brain phospholipids by up to 80% and attenuated brain phospholipase A2 activity, the lack of effect of lithium on docosahexaenoate recycling and turnover suggests that a target for lithium's action is an arachidonic acid-selective phospholipase A2.


Assuntos
Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Ácidos Docosa-Hexaenoicos/metabolismo , Lítio/farmacologia , Acil Coenzima A/metabolismo , Animais , Ácido Araquidônico/metabolismo , Ácidos Docosa-Hexaenoicos/sangue , Ácidos Graxos não Esterificados/metabolismo , Metabolismo dos Lipídeos , Lítio/administração & dosagem , Masculino , Fosfolipases A/metabolismo , Fosfolipases A2 , Fosfolipídeos/metabolismo , Ratos , Ratos Endogâmicos F344
12.
Neurochem Res ; 23(10): 1251-7, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9804280

RESUMO

The Fatty Acid method was used to determine whether incorporation of plasma radiolabeled arachidonic acid into brain phospholipids is controlled by phospholipase A2. Awake rats received an i.v. injection of a phospholipase A2 inhibitor, manoalide (10 mg/kg), and then were infused i.v. with [1-(14)C]arachidonate or [3H]arachidonate. Animals were killed after infusion by microwave irradiation, and tracer distribution was analyzed in brain phospholipid, neutral lipid and acyl-CoA pools. Calcium-independent phospholipase A2 activity in brain homogenate was reduced by manoalide, whereas phospholipase C activity was unaffected. At 60 min but not at 20 or 40 min after its injection, manoalide had significantly decreased by 50% incorporation of unesterified arachidonate into and turnover within brain phospholipids, taking into account dilution of the brain arachidonoyl-CoA pool by recycled arachidonate. Manoalide also increased by 100% the net rate of unesterified arachidonate incorporation into brain triacylglycerol. This study indicates that manoalide can be used to inhibit brain phospholipase A2 in vivo, and that phospholipase A2 plays a critical role in arachidonate turnover in brain phospholipids and neutral lipids.


Assuntos
Ácido Araquidônico/metabolismo , Encéfalo/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Fosfolipases A/antagonistas & inibidores , Fosfolipídeos/metabolismo , Terpenos/farmacologia , Acil Coenzima A/metabolismo , Animais , Encéfalo/metabolismo , Masculino , Modelos Biológicos , Fosfolipases A2 , Ratos , Ratos Endogâmicos F344 , Vigília
13.
Mol Chem Neuropathol ; 34(1): 79-101, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9778647

RESUMO

Transient cerebral ischemia (5 min) releases unesterified fatty acids from membrane phospholipids, increasing brain concentrations of fatty acids for up to 1 h following reperfusion. To understand the reported anti-ischemic effect of Ginkgo biloba extract (EGb 761), we monitored its effect on brain fatty acid reincorporation in a gerbil-stroke model. Both common carotid arteries in awake gerbils were occluded for 5 min, followed by 5 min of reperfusion. Animals were infused intravenously with labeled arachidonic (AA) or palmitic acid (Pam), and rates of incorporation of unlabeled fatty acid from the brian acyl-CoA pool were calculated by the model of Robinson et al. (1992), using quantitative autoradiography and biochemical analysis of brain acyl-CoA. Animals were treated for 14 d with 50 or 150 mg/kg/d EGb 761 or vehicle. Ischemia-reperfusion had no effect on the rate of unlabeled Pam incorporation into brain phospholipids from palmitoyl-CoA; this rate also was unaffected by EGb 761. In contrast, ischemia-reperfusion increased the rate of incorporation of unlabeled AA from brain arachidonoyl-CoA by a factor of 2.3-3.3 compared with the control rate; this factor was further augmented to 3.6-5.0 by pretreatment with EGb 761. There is selective reincorporation of AA compared with Pam into brain phospholipids following ischemia. EGb 761 further accelerates AA reincorporation, potentially reducing neurotoxic effects of prolonged exposure of brain to high concentrations of AA and its metabolites.


Assuntos
Química Encefálica/efeitos dos fármacos , Ácidos Graxos/metabolismo , Ginkgo biloba/química , Ataque Isquêmico Transitório/tratamento farmacológico , Lipídeos de Membrana/metabolismo , Fármacos Neuroprotetores/farmacologia , Fosfolipídeos/metabolismo , Extratos Vegetais , Plantas Medicinais , Traumatismo por Reperfusão/prevenção & controle , Animais , Ácido Araquidônico/metabolismo , Flavonoides , Gerbillinae , Ataque Isquêmico Transitório/metabolismo , Masculino , Fármacos Neuroprotetores/uso terapêutico , Ácido Palmítico/metabolismo , Traumatismo por Reperfusão/metabolismo , Vigília
14.
Neurochem Res ; 23(4): 551-5, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9566591

RESUMO

The cholinergic agonist, arecoline, was used to examine the effects of cholinergic stimulation upon incorporation of radiolabeled arachidonic acid from blood into cerebral microvessels of awake rats. Animals received a single i.p. injection of arecoline (1 mg/kg) followed 3 to 5 minutes later by a 5 minute intravenous infusion of [1-14C]arachidonic acid (AA) (170 microCi/kg) via the femoral vein. Timed arterial blood samples were collected over 20 minutes following the start of infusion, after which the animal was killed, and the brain was removed. The incorporation coefficient k* for [1-14C]AA was approximately 2-fold higher in microvessels isolated from arecoline-injected than from sham-injected animals. The data demonstrate in an in vivo paradigm, that activation of cholinergic pathways within the rat CNS stimulates arachidonic acid turnover in cerebral microvessels. This suggests a direct involvement of this fatty acid in second messenger function within microvessel endothelial cells and possibly attached pericytes.


Assuntos
Ácido Araquidônico/metabolismo , Arecolina/farmacologia , Barreira Hematoencefálica/fisiologia , Encéfalo/metabolismo , Circulação Cerebrovascular/fisiologia , Microcirculação/fisiologia , Animais , Ácido Araquidônico/sangue , Barreira Hematoencefálica/efeitos dos fármacos , Encéfalo/irrigação sanguínea , Radioisótopos de Carbono , Circulação Cerebrovascular/efeitos dos fármacos , Cinética , Masculino , Microcirculação/efeitos dos fármacos , Técnica de Diluição de Radioisótopos , Ratos , Ratos Endogâmicos F344 , Vigília
15.
J Neurochem ; 70(1): 325-34, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9422378

RESUMO

Awake gerbils were subjected to 5 min of forebrain ischemia by clamping the carotid arteries for 5 min and then allowing recirculation. Radiolabeled arachidonic or palmitic acid was infused intravenously for 5 min at the start of recirculation, after which the brains were prepared for quantitative autoradiography or chemical analysis. Dilution of specific activity of the acyl-CoA pool was independently determined for these fatty acids in control gerbils and following 5 min of ischemia and 5 min of reperfusion. Using a quantitative method for measuring regional in vivo fatty acid incorporation into and turnover within brain phospholipids and determining unlabeled concentrations of acyl-CoAs following recirculation, it was shown that reperfusion after 5 min of ischemia was accompanied by a threefold increase compared with the control in the rate of reincorporation of unlabeled arachidonate that had been released during ischemia, whereas reincorporation of released palmitate was not different from the control. Selective and accelerated reincorporation of arachidonate into brain phospholipids shortly after ischemia may ameliorate specific deleterious effects of arachidonate and its metabolites on brain membranes.


Assuntos
Ácido Araquidônico/metabolismo , Encéfalo/metabolismo , Ataque Isquêmico Transitório/metabolismo , Lipídeos de Membrana/metabolismo , Fosfolipídeos/metabolismo , Reperfusão , Acil Coenzima A/metabolismo , Animais , Autorradiografia , Ácidos Graxos/metabolismo , Ácidos Graxos não Esterificados/metabolismo , Gerbillinae , Processamento de Imagem Assistida por Computador , Técnicas de Diluição do Indicador , Masculino , Palmitatos/metabolismo
17.
Ann N Y Acad Sci ; 820: 56-73; discussion 73-4, 1997 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-9237449

RESUMO

An in vivo method is presented that allows quantification and imaging of fatty acid incorporation into different brain phospholipids in relation to membrane synthesis, neuroplasticity, and signal transduction. The method can be used with positron emission tomography, and may help to evaluate brain phospholipid metabolism in humans with brain tumors, neurodegenerative disease, cerebral ischemia or trauma, or neurotoxic effects of drugs or other agents.


Assuntos
Animais Domésticos , Encéfalo/metabolismo , Ácidos Graxos/metabolismo , Plasticidade Neuronal , Fosfolipídeos/metabolismo , Transdução de Sinais , Animais , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Ácidos Graxos/administração & dosagem , Humanos , Injeções Intravenosas , Cintilografia
18.
J Neurochem ; 68(5): 2111-8, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9109539

RESUMO

Transient global cerebral ischemia affects phospholipid metabolism and features a considerable increase in unesterified fatty acids. Reincorporation of free fatty acids into membrane phospholipids during reperfusion following transient ischemia depends on conversion of fatty acids to acyl-CoAs via acyl-CoA synthetases and incorporation of the acyl group into lysophospholipids. To study the effect of ischemia-reperfusion on brain fatty acid and acyl-CoA pools, the common carotid arteries were tied for 5 min in awake gerbils, after which the ligatures were released for 5 min and the animals were killed by microwave irradiation. Twenty percent of these animals (two of 10) were excluded from the ischemia-reperfusion group when it was demonstrated statistically that brain unesterified arachidonic acid concentration was not elevated beyond the range of the control group. Brain unesterified fatty acid concentration was increased 4.4-fold in the ischemic-reperfused animals, with stearic acid and arachidonic acid increasing the most among the saturated and polyunsaturated fatty acids, respectively. The total acyl-CoA concentration remained unaffected, indicating that reacylation of membrane lysophospholipids is maintained during recovery. However, there was a substantial increase in the stearoyl- and arachidonoyl-CoA and a marked decrease in palmitoyl- and docosahexaenoyl-CoA. These results suggest that unesterified fatty acid reacylation into phospholipids is reprioritized according to the redistribution in concentration of acyl-CoA molecular species, with incorporation of stearic acid and especially arachidonic acid being favored.


Assuntos
Acil Coenzima A/metabolismo , Isquemia Encefálica/metabolismo , Encéfalo/metabolismo , Traumatismo por Reperfusão/metabolismo , Animais , Ácidos Graxos não Esterificados/metabolismo , Gerbillinae , Masculino , Concentração Osmolar , Valores de Referência , Distribuição Tecidual
20.
J Lipid Res ; 38(2): 295-300, 1997 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9162749

RESUMO

We examined the effect of a clinically therapeutic dose of methyl 2-tetradecylglycidate (McN-3716, methyl palmoxirate, MEP) (2.5 mg/kg), an inhibitor of beta-oxidation of fatty acids, on incorporation of radiolabeled palmitic acid ([U-14C]PAM) from plasma into brain lipids of awake rats. Four hour pretreatment with 2.5 mg/kg MEP significantly increased the incorporation of [U-14C]PAM into brain lipids and substantially decreased aqueous radiolabeled metabolites in brain that can constitute unwanted background signal when analyzed by quantitative autoradiography. MEP treatment increased the lipid to aqueous background radioactivity from 0.8 to 3.0. Net rate of incorporation, k*, was significantly increased (60%) by MEP and was attributed to incorporation of [U-14C]PAM into phospholipid and triglyceride brain compartments. MEP treatment did not affect the size of the fatty acyl-CoA pool or the distribution of the various molecular acyl-CoA species. These results indicate that MEP, at a dose of 2.5 mg/kg (per os), can be used to increase incorporation of [1-(11C)]PAM for studying brain lipid metabolism in humans by positron emission tomography (PET).


Assuntos
Acil Coenzima A/biossíntese , Encéfalo/metabolismo , Compostos de Epóxi/farmacologia , Hipoglicemiantes/farmacologia , Metabolismo dos Lipídeos , Ácido Palmítico/metabolismo , Propionatos/farmacologia , Acil Coenzima A/classificação , Acil Coenzima A/efeitos dos fármacos , Animais , Encéfalo/efeitos dos fármacos , Radioisótopos de Carbono , Lipídeos/classificação , Masculino , Oxirredução , Ácido Palmítico/análise , Fosfolipídeos/biossíntese , Fosfolipídeos/classificação , Ratos , Ratos Endogâmicos F344
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