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1.
J Neurol ; 270(8): 3970-3980, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37133535

RESUMO

BACKGROUND AND OBJECTIVES: Primary lateral sclerosis (PLS) is a motor neuron disease characterised by loss of the upper motor neurons. Most patients present with slowly progressive spasticity of the legs, which may also spread to the arms or bulbar regions. It is challenging to distinguish between PLS, early-stage amyotrophic lateral sclerosis (ALS) and hereditary spastic paraplegia (HSP). The current diagnostic criteria advise against extensive genetic testing. This recommendation is, however, based on limited data. METHODS: We aim to genetically characterize a PLS cohort using whole exome sequencing (WES) for genes associated with ALS, HSP, ataxia and movement disorders (364 genes) and C9orf72 repeat expansions. Patients fulfilling the definite PLS criteria by Turner et al. and with available DNA samples of sufficient quality were recruited from an on-going, population-based epidemiological study. Genetic variants were classified according to the ACMG criteria and assigned to groups based on disease association. RESULTS: WES was performed in 139 patients and the presence of repeat expansions in C9orf72 was analysed separately in 129 patients. This resulted in 31 variants of which 11 were (likely) pathogenic. (Likely) pathogenic variants resulted in 3 groups based on disease association: ALS-FTD (C9orf72, TBK1), pure HSP (SPAST, SPG7), "ALS-HSP-CMT overlap" (FIG4, NEFL, SPG11). DISCUSSION: In a cohort of 139 PLS patients, genetic analyses resulted in 31 variants (22%) of which 10 (7%) (likely) pathogenic associated with different diseases (predominantly ALS and HSP). Based on these results and the literature, we advise to consider genetic analyses in the diagnostic work-up for PLS.


Assuntos
Esclerose Lateral Amiotrófica , Demência Frontotemporal , Doença dos Neurônios Motores , Humanos , Esclerose Lateral Amiotrófica/diagnóstico , Proteína C9orf72/genética , Demência Frontotemporal/complicações , Doença dos Neurônios Motores/diagnóstico , Neurônios Motores/patologia , Espastina , Proteínas , Flavoproteínas , Monoéster Fosfórico Hidrolases
2.
Front Neurosci ; 15: 711074, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34658762

RESUMO

Purpose: A former rodent study showed that cerebral traumatic microbleeds (TMBs) may temporarily become invisible shortly after injury when detected by susceptibility weighted imaging (SWI). The present study aims to validate this phenomenon in human SWI. Methods: In this retrospective study, 46 traumatic brain injury (TBI) patients in various forms of severity were included and willingly complied with our strict selection criteria. Clinical parameters potentially affecting TMB count, Rotterdam and Marshall CT score, Mayo Clinic Classification, contusion number, and total volume were registered. The precise time between trauma and MRI [5 h 19 min to 141 h 54 min, including SWI and fluid-attenuated inversion recovery (FLAIR)] was individually recorded; TMB and FLAIR lesion counts were assessed. Four groups were created based on elapsed time between the trauma and MRI: 0-24, 24-48, 48-72, and >72 h. Kruskal-Wallis, ANOVA, Chi-square, and Fisher's exact tests were used to reveal differences among the groups within clinical and imaging parameters; statistical power was calculated retrospectively for each comparison. Results: The Kruskal-Wallis ANOVA with Conover post hoc analysis showed significant (p = 0.01; 1-ß > 0.9) median TMB number differences in the subacute period: 0-24 h = 4.00 (n = 11); 24-48 h = 1 (n = 14); 48-72 h = 1 (n = 11); and 72 h ≤ 7.5 (n = 10). Neither clinical parameters nor FLAIR lesions depicted significant differences among the groups. Conclusion: Our results demonstrate that TMBs on SWI MRI may temporarily become less detectable at 24-72 h following TBI.

3.
Science ; 368(6493): 897-901, 2020 05 22.
Artigo em Inglês | MEDLINE | ID: mdl-32381591

RESUMO

Cytotoxic T lymphocytes (CTLs) kill infected and cancerous cells. We detected transfer of cytotoxic multiprotein complexes, called supramolecular attack particles (SMAPs), from CTLs to target cells. SMAPs were rapidly released from CTLs and were autonomously cytotoxic. Mass spectrometry, immunochemical analysis, and CRISPR editing identified a carboxyl-terminal fragment of thrombospondin-1 as an unexpected SMAP component that contributed to target killing. Direct stochastic optical reconstruction microscopy resolved a cytotoxic core surrounded by a thrombospondin-1 shell of ~120 nanometer diameter. Cryo-soft x-ray tomography analysis revealed that SMAPs had a carbon-dense shell and were stored in multicore granules. We propose that SMAPs are autonomous extracellular killing entities that deliver cytotoxic cargo targeted by the specificity of shell components.


Assuntos
Citotoxicidade Imunológica , Granzimas/metabolismo , Complexos Multiproteicos/metabolismo , Perforina/metabolismo , Linfócitos T Citotóxicos/metabolismo , Trombospondina 1/metabolismo , Sistemas CRISPR-Cas , Exocitose , Edição de Genes , Humanos , Células K562 , Trombospondina 1/genética , Tomografia por Raios X
4.
Neurology ; 93(17): e1605-e1617, 2019 10 22.
Artigo em Inglês | MEDLINE | ID: mdl-31578300

RESUMO

OBJECTIVE: To define the natural history of the C9orf72 amyotrophic lateral sclerosis (C9ALS) patient population, develop disease biomarkers, and characterize patient pathologies. METHODS: We prospectively collected clinical and demographic data from 116 symptomatic C9ALS and 12 non-amyotrophic lateral sclerosis (ALS) full expansion carriers across 7 institutions in the United States and the Netherlands. In addition, we collected blood samples for DNA repeat size assessment, CSF samples for biomarker identification, and autopsy samples for dipeptide repeat protein (DPR) size determination. Finally, we collected retrospective clinical data via chart review from 208 individuals with C9ALS and 450 individuals with singleton ALS. RESULTS: The mean age at onset in the symptomatic prospective cohort was 57.9 ± 8.3 years, and median duration of survival after onset was 36.9 months. The monthly change was -1.8 ± 1.7 for ALS Functional Rating Scale-Revised and -1.4% ± 3.24% of predicted for slow vital capacity. In blood DNA, we found that G4C2 repeat size correlates positively with age. In CSF, we observed that concentrations of poly(GP) negatively correlate with DNA expansion size but do not correlate with measures of disease progression. Finally, we found that size of poly(GP) dipeptides in the brain can reach large sizes similar to that of their DNA repeat derivatives. CONCLUSIONS: We present a thorough investigation of C9ALS natural history, providing the basis for C9ALS clinical trial design. We found that clinical features of this genetic subset are less variant than in singleton ALS. In addition, we identified important correlations of C9ALS patient pathologies with clinical and demographic data.


Assuntos
Esclerose Lateral Amiotrófica/genética , Esclerose Lateral Amiotrófica/metabolismo , Proteína C9orf72/genética , Idade de Início , Esclerose Lateral Amiotrófica/epidemiologia , Biomarcadores/sangue , Biomarcadores/líquido cefalorraquidiano , Biomarcadores/urina , Expansão das Repetições de DNA , Feminino , Seguimentos , Heterozigoto , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Estudos Retrospectivos
5.
Artigo em Inglês | MEDLINE | ID: mdl-31134825

RESUMO

Background: Primary lateral sclerosis (PLS) is a rare motor neuron disease characterized by progressive degeneration of upper motor neurons, resulting in spasticity and disability. There is, however, mounting evidence that the disease is not limited to upper motor neurons alone and that cognitive and behavioral changes within the spectrum of frontotemporal dementia (FTD) are part of the clinical phenotype. Objectives: To provide an in-depth classification of the cognitive and behavioral profiles of PLS by using the golden standard, a full neuropsychological evaluation, as well as a comprehensive behavioral assessment in a cohort of 30 cases. Results: Only 7 out of 30 PLS patients scored within normal range on all of the tests within our battery. The neuropsychological profile of PLS consists of deficits in social cognition (affective theory of mind (ToM) in particular), fluency, executive functions and memory. Using the revised Strong criteria, we could classify 57% of patients within the FTD spectrum (of which 17% had behavioral variant FTD). An additional 20% of patients had deficits which were not characteristic of FTD. Conclusions: This study confirms that PLS is not a restricted phenotype (only affecting upper motor neurons) and that behavioral and cognitive changes are common. Therefore, clinicians treating PLS patients should routinely assess cognition and behavior as part of routine care as cognitive and behavioral changes impact management, decision-making and care-giver burden. This assessment should be sensitive to the neuropsychological profile of PLS (social cognition (affective ToM in particular), fluency, executive functions and memory) and behavioral changes.


Assuntos
Doença dos Neurônios Motores/diagnóstico , Doença dos Neurônios Motores/psicologia , Testes Neuropsicológicos , Comportamento Social , Teoria da Mente/fisiologia , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
6.
J Neurol Neurosurg Psychiatry ; 90(2): 141-147, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30076267

RESUMO

OBJECTIVES: Cognitive and behavioural changes within the spectrum of frontotemporal dementia (FTD) are observed frequently in patients with amyotrophic lateral sclerosis (ALS). Whether these changes also occur in other forms of motor neuron disease (MND) is not well studied. We therefore systemically screened a large cohort of patients with primary lateral sclerosis (PLS) and progressive muscular atrophy (PMA) for cognitive and behavioural changes, and subsequently compared our findings with a cohort of patients with ALS. METHODS: Using a set of screening instruments (Edinburgh Cognitive and Behavioural ALS Screen, ALS and Frontotemporal Dementia Questionnaire, Frontal Assessment Battery, and Hospital Anxiety and Depression Scale), the presence of cognitive and behavioural changes as well as anxiety and depression in 277 patients with ALS, 75 patients with PLS and 143 patients with PMA was evaluated retrospectively. RESULTS: We found a high frequency of cognitive and behavioural abnormalities with similar profiles in all three groups. Subjects with behavioural variant FTD were identified in all groups. CONCLUSIONS: The percentage of patients with PLS and PMA with cognitive dysfunction was similar to patients with ALS, emphasising the importance for cognitive screening as part of routine clinical care in all three patient groups. With a similar cognitive profile, in line with genetic and clinical overlap between the MNDs, the view of PLS as an MND exclusively affecting upper motor neurons and PMA exclusively affecting lower motor neurons cannot be held. Therefore, our findings are in contrast to the recently revised El Escorial criteria of 2015, where PLS and PMA are described as restricted phenotypes. Our study favours a view of PLS and PMA as multidomain diseases similar to ALS.


Assuntos
Esclerose Lateral Amiotrófica/psicologia , Disfunção Cognitiva/epidemiologia , Transtornos Mentais/epidemiologia , Doença dos Neurônios Motores/psicologia , Atrofia Muscular Espinal/psicologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Esclerose Lateral Amiotrófica/diagnóstico , Disfunção Cognitiva/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Fenótipo , Estudos Retrospectivos
7.
Artigo em Inglês | MEDLINE | ID: mdl-28745069

RESUMO

OBJECTIVE: Primary lateral sclerosis (PLS) is a rare form of motor neuron disease characterised by UMN degeneration leading to slowly progressive spasticity. Whether it is a separate disease or a subtype of ALS has been debated. In ALS comorbid frontotemporal dementia (FTD) is frequently seen (±15%). However, cognitive and behavioural changes are generally not considered to be a part of PLS. METHODS: To report the clinical findings and frequency of PLS patients that developed FTD in a referral-based cohort and provide an overview of the literature. RESULTS: In our cohort six out of 181 (3.3%) PLS patients developed FTD. In the literature a few cases of PLS with FTD have been reported and only a limited number of small studies have investigated cognition in PLS. However, when these studies are summarised a pattern emerges with FTD diagnoses in ±2% and frontotemporal impairment in 22% of patients. CONCLUSIONS: These findings suggest that PLS is part of the FTD-MND continuum and would favour viewing it as a subtype of ALS. It is, however, not a restricted (isolated UMN involvement) phenotype.


Assuntos
Demência Frontotemporal/diagnóstico , Doença dos Neurônios Motores/diagnóstico , Avaliação de Sintomas/métodos , Idoso , Diagnóstico Diferencial , Feminino , Demência Frontotemporal/classificação , Demência Frontotemporal/complicações , Humanos , Masculino , Pessoa de Meia-Idade , Doença dos Neurônios Motores/classificação , Doença dos Neurônios Motores/complicações , Fatores de Risco
8.
Phys Chem Chem Phys ; 16(9): 4023-32, 2014 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-24445535

RESUMO

Highly concentrated alkaline NaOH-Ga(OH)3 solutions with 1.18 M ≤ [Ga(III)]T ≤ 2.32 M and 2.4 M ≤ [NaOH]T ≤ 4.9 M (where the subscript T denotes total or analytical concentrations) have been prepared and investigated by solution X-ray diffraction and also by ab initio quantum chemical calculations. The data obtained are consistent with the presence of only one predominant Ga(III)-bearing species in these solutions, which is the tetrahedral hydroxo complex Ga(OH)4(-). This finding is in stark contrast to that found for Al(III)-containing solutions of similar concentrations, in which, besides the monomeric complex, an oxo-bridged dimer was also found to form. From the solution X-ray diffraction measurements, the formation of the dimeric (OH)3Ga-O-Ga(OH)3(2-) could not unambiguously be shown, however, from the comparison of experimental IR, Raman and (71)Ga NMR spectra with calculated ones, its formation can be safely excluded. Moreover, higher mononuclear stepwise hydroxo complexes, like Ga(OH)6(3-), which have been claimed to exist by others in the literature, were not possible to experimentally detect in these solutions with any of the spectroscopic techniques used.


Assuntos
Gálio/química , Hidróxido de Sódio/química , Modelos Moleculares , Conformação Molecular , Soluções/química , Água/química , Difração de Raios X
9.
Schizophr Res ; 122(1-3): 85-93, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20627227

RESUMO

Neuropsychological characterization of the schizophrenia deficit syndrome is an unresolved issue. The initial assumption was that patients with deficit syndrome show more definitive impairments on tests sensitive for frontal and parietal functions compared with nondeficit patients,but recent studies failed to confirm this assumption. The fundamental question is whether a more refined delineation of executive dysfunctions is able to yield differences between deficit and nondeficit patients. To investigate this question, we implemented a factor analytic approach to explore potential differences between deficit and nondeficit patients using the Wisconsin Card Sorting Test (WCST). Our paper presents an exploratory factor analysis of the WCST on schizophrenia patients and healthy samples, and a comparison among deficit, non-deficit patients with schizophrenia and control samples using the identified factors. A total of 154 patients with schizophrenia fulfilling the criteria for the deficit syndrome, 121 nondeficit patients, and 130 healthy controls were compared. Factor analysis of the WCST variables using the principal component method resulted in a two-factor solution. Comparison of the diagnostic groups on each of the factors revealed that deficit schizophrenia patients suffer from a more severe degree of impairment on the 'General executive function' factor than nondeficit schizophrenia patients. To our knowledge this is the first study that compared patients with the deficit and non-deficit forms of schizophrenia using WCST factor analytic techniques. Our results provide an insight into the cognitive profile of schizophrenia patients with regard to WCST, which could serve as a framework for future clinical and research endeavors.


Assuntos
Transtornos Cognitivos/etiologia , Função Executiva/fisiologia , Esquizofrenia/complicações , Adolescente , Adulto , Idoso , Análise de Variância , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Escalas de Graduação Psiquiátrica , Adulto Jovem
10.
Psychol Med ; 39(8): 1337-45, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18713489

RESUMO

BACKGROUND: Despite the growing recognition that the clinical symptom characteristics associated with attention deficit hyperactivity disorder (ADHD) persist into adulthood in a high proportion of subjects, little is known about the persistence of neurocognitive deficits in ADHD. The objective was twofold: (1) to conduct a meta-analysis of neuropsychological studies to characterize attentional performance in subjects with adult ADHD by examining differences in ADHD versus normal control subjects; and (2) to investigate whether these differences vary as a function of age and gender. METHOD: Twenty-five neuropsychological studies comparing subjects with adult ADHD and healthy controls were evaluated. Statistical effect size was determined to characterize the difference between ADHD and control subjects. Meta-regression analysis was applied to investigate whether the difference between ADHD and control subjects varied as a function of age and gender across studies. RESULTS: Tests measuring focused and sustained attention yielded an effect size with medium to large magnitude whereas tests of simple attention resulted in a small to medium effect size in terms of poorer attention functioning of ADHD subjects versus controls. On some of the measures (e.g. Stroop interference), a lower level of attention functioning in the ADHD group versus the controls was associated with male gender. CONCLUSIONS: Adult ADHD subjects display significantly poorer functioning versus healthy controls on complex but not on simple tasks of attention, and the degree of impairment varies with gender, with males displaying a higher level of impairment.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico , Transtornos Cognitivos/diagnóstico , Testes Neuropsicológicos/estatística & dados numéricos , Adulto , Fatores Etários , Atenção , Transtorno do Deficit de Atenção com Hiperatividade/epidemiologia , Transtorno do Deficit de Atenção com Hiperatividade/psicologia , Transtornos Cognitivos/epidemiologia , Transtornos Cognitivos/psicologia , Comorbidade , Estudos Transversais , Feminino , Humanos , Masculino , Psicometria , Desempenho Psicomotor , Tempo de Reação , Valores de Referência , Fatores Sexuais , Escalas de Wechsler/estatística & dados numéricos , Adulto Jovem
11.
Mol Ecol ; 15(12): 3707-14, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17032268

RESUMO

The domestication of the Eurasian grape (Vitis vinifera ssp. sativa) from its wild ancestor (Vitis vinifera ssp. sylvestris) has long been claimed to have occurred in Transcaucasia where its greatest genetic diversity is found and where very early archaeological evidence, including grape pips and artefacts of a 'wine culture', have been excavated. Whether from Transcaucasia or the nearby Taurus or Zagros Mountains, it is hypothesized that this wine culture spread southwards and eventually westwards around the Mediterranean basin, together with the transplantation of cultivated grape cuttings. However, the existence of morphological differentiation between cultivars from eastern and western ends of the modern distribution of the Eurasian grape suggests the existence of different genetic contribution from local sylvestris populations or multilocal selection and domestication of sylvestris genotypes. To tackle this issue, we analysed chlorotype variation and distribution in 1201 samples of sylvestris and sativa genotypes from the whole area of the species' distribution and studied their genetic relationships. The results suggest the existence of at least two important origins for the cultivated germplasm, one in the Near East and another in the western Mediterranean region, the latter of which gave rise to many of the current Western European cultivars. Indeed, over 70% of the Iberian Peninsula cultivars display chlorotypes that are only compatible with their having derived from western sylvestris populations.


Assuntos
DNA de Cloroplastos/química , Polimorfismo Genético , Vitis/classificação , Europa (Continente) , Genótipo , Região do Mediterrâneo , Repetições de Microssatélites , Oriente Médio , Filogenia , Vitis/genética
12.
Schweiz Med Wochenschr ; 122(16): 582-7, 1992 Apr 18.
Artigo em Alemão | MEDLINE | ID: mdl-1579864

RESUMO

From 1980 to 1987 an epidemiologic survey was conducted in northwestern Switzerland (population 523,000) with the aim of registering as many MS cases as possible. The prevalence for the entire region was 142 per 100,000, with a maximum of 164/100,000 in the city of Basle. Extrapolation suggests there are more than 8000 MS patients living in Switzerland. Other interesting results were: a sex-ratio of 2.2 females:1 male. The mean age at clinical onset was 31.6 years. The mean survival was 30.6 years. Prevalence has grown in recent decades, mainly due to longer survival and to changes in age structure. The incidence presumably remained unchanged.


Assuntos
Esclerose Múltipla/epidemiologia , Vigilância da População , Adulto , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/mortalidade , Prevalência , Razão de Masculinidade , Suíça/epidemiologia
14.
Orv Hetil ; 132(8): 395-400, 1991 Feb 24.
Artigo em Húngaro | MEDLINE | ID: mdl-2003026

RESUMO

Among other elements (manganese, molybdenum, cadmium, mercury, lead, nickel), the levels of selenium in healthy human sera (n = 56) and plasma (n = 15) were measured by ICP spectrometry. It was ascertained by the multielement analysis that of 40 nineteen year-old males (from 28 different villages in one county 15 showed lower than detectable levels of selenium in their sera (n = 25) and plasma (n = 15) samples. For this reason, the selenium contents of the sera of 31 blood donors were determined by the ICP spectrometry, with hybrid generation. By this same technique the selenium in sera of 16 men aged between 24-60 years (mean = 43.3 years) was measured as 24.06 micrograms/l (13-42 micrograms/l), while in 15 women between the ages of 19-64 years (mean 39.3 years) it amounted to 20.86 micrograms/l (11-31 micrograms/l). In 28 cases from 40 samples (25 sera and 15 plasma) the concentration of molybdenum was smaller than the detectable limit (less than 0.0011 mg/l). Firstly, these results prove that amongst healthy individuals, in Hungary, molybdenum and selenium deficiency states exist. The authors conclude that there is a relationship between these deficiency states, as risk factors, and the frequently occurring diseases (malignant tumours, cardiovascular diseases, etc.) in Hungary.


Assuntos
Oligoelementos/sangue , Humanos , Plasma/química , Oligoelementos/deficiência
15.
J Cardiovasc Pharmacol ; 12(6): 621-8, 1988 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-2467078

RESUMO

Isolated guinea pig hearts subjected to global ischemia, were used to investigate whether lidocaine exerts an antiarrhythmic action against reperfusion-induced arrhythmias, and the effects of this drug upon myocardial ion contents during ischemia and reperfusion were studied. In the first series of experiments, the drug was administered 5 min prior to the induction of global ischemia and maintained during reperfusion. With 3.6 X 10(-6), 7.2 X 10(-6), 14.7 X 10(-6), and 29.5 X 10(-6) mol/L lidocaine, reperfusion-induced ventricular fibrillation and tachycardia were reduced from their control incidence of 83% and 100% to 41% and 58%, 33% (p less than 0.05) and 25% (p less than 0.001), 8% (p less than 0.01) and 8% (p less than 0.001), 0% (p less than 0.001) and 0% (p less than 0.001), respectively. The ion contents of myocardium were determined by atomic absorption spectrophotometer after washout of the ions from vasculature. Ischemia induced a marked accumulation of sodium and loss of potassium in the myocardial tissue. Both ischemia-induced sodium gain and potassium loss were significantly inhibited by lidocaine treatment. During reperfusion, sodium was further increased in the control group and this value was significantly lower in the lidocaine-treated group after 1 min of reperfusion. Sodium content remained at nearly constant level for the rest of reperfusion period. Potassium was suddenly increased during the first 5 min of reperfusion then continuously decreased until the end of reperfusion.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Arritmias Cardíacas/prevenção & controle , Doença das Coronárias/tratamento farmacológico , Lidocaína/uso terapêutico , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Miocárdio/metabolismo , Animais , Arritmias Cardíacas/etiologia , Cálcio/metabolismo , Relação Dose-Resposta a Droga , Cobaias , Masculino , Potássio/metabolismo , Sódio/metabolismo , Fatores de Tempo
16.
Cardiovasc Res ; 22(11): 818-25, 1988 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-3256423

RESUMO

Using the isolated perfused rat heart with transient (10 min) regional ischaemia induced by coronary artery ligation, we have shown that slow heart rate can dramatically reduce the vulnerability of the myocardium to reperfusion induced ventricular fibrillation and ventricular tachycardia. In the heart rate range of 200-400 beats.min-1, slower heart rates exerted a frequency dependent protective effect against reperfusion induced arrhythmias. At the optimal rate of 200 beats.min-1, the incidence of total ventricular fibrillation (irreversible plus reversible) and ventricular tachycardia fell to 33% and 50% of their control values (100%). The anti-arrhythmic effect was achieved with only a minor (less than 20%) effect on coronary flow. To ascertain whether or not slow heart rate achieved an absolute reduction in vulnerability to arrhythmias irrespective of the duration of ischaemia, hearts were also subjected to 5, 10, 20, 30 or 40 min of ischaemia followed by 30 min of reperfusion with and without pacing at 200 beats.min-1. A bellshaped time-response profile was obtained in both groups. In unpaced controls (n = 12) this gave a maximal vulnerability to arrhythmias after 10 min of ischaemia. In the paced hearts (n = 12) the curve was shifted to the right, with a peak vulnerability at 20 min. These results show that the action of pacing is to exert a delaying effect which extends the duration of ischaemia that can be tolerated before the heart becomes vulnerable to reperfusion induced arrhythmias. Heart rate can have a substantial effect on reperfusion induced arrhythmias and should be considered when making therapeutic interventions and risk assessments in this setting.


Assuntos
Arritmias Cardíacas/etiologia , Estimulação Cardíaca Artificial , Frequência Cardíaca , Traumatismo por Reperfusão Miocárdica/etiologia , Animais , Circulação Coronária , Doença das Coronárias/fisiopatologia , Técnicas In Vitro , Masculino , Ratos , Ratos Endogâmicos , Fatores de Tempo
17.
Exp Cell Biol ; 52(5): 279-85, 1984.
Artigo em Inglês | MEDLINE | ID: mdl-6479429

RESUMO

Alterations in ornithine decarboxylase (ODC) activity and in the polyamine and nucleic acid (RNA and DNA) concentrations were studied in P388 leukemia cells and in the host liver at different times after intraperitoneal inoculation of 5 X 10(6) tumor cells into BDF1 mice. ODC activity of leukemia cells had a maximum at day 5 after tumor transplantation. Cellular spermidine concentration declined significantly during the first 5 to 6 days. The RNA concentration of tumor cells changed parallel to that of spermidine. In the livers of ascites tumor-bearing mice ODC activity was 5- to 20-fold of control and had a maximum at days 5 to 6 after tumor cell inoculation. Spermidine concentration in the host liver increased, whereas spermine decreased gradually with tumor growth.


Assuntos
Leucemia Experimental/metabolismo , Fígado/metabolismo , Ornitina Descarboxilase/análise , Poliaminas/metabolismo , Animais , Feminino , Leucemia Experimental/enzimologia , Fígado/enzimologia , Masculino , Camundongos , Transplante de Neoplasias , RNA Neoplásico/análise , Fatores de Tempo
18.
Ther Hung ; 28(2): 75-8, 1980.
Artigo em Inglês | MEDLINE | ID: mdl-7466718

RESUMO

PIP: The effect of Rigevidon, a recently developed oral contraceptive (OC), was examined in 53 women during 426 cycles and was compared to the observations made with Ovidon in 46 women during 413 cycles. After recording the history of patients, the following examinations were performed: bimanual gynecological examination; vaginal smear; Papanicolaou staining; liver function test; and determination of urobilinogen. 6 women in the Rigevidon group and 4 in the Ovidon group discontinued the regular use of the drug, for different reasons. Rigevidon was found to be a reliable contraceptive. It caused significantly less unwanted effects than could have been expected on the basis of its composition. Due to its low hormone content (0.15 mg d-norgestrel and 0.03 mg ethinyloestradiol), it is important to inform acceptors of the proper use of tablets. In evaluating the unwanted effects, the hormonal constitution of the woman must always be considered. The unwanted effects may be controlled relatively easily. The physical performance of 1 sportswoman was increased due to the decrease of pathological vaginal discharge. In 2 women there was good tolerance of Rigevidon despite varicosity. Nausea and breast discomfort occurred in a number of women during Ovidon treatment but were not observed with Rigevidon. Weight gain was not observed in any of the cases.^ieng


Assuntos
Anticoncepcionais Orais Combinados/farmacologia , Anticoncepcionais Orais/farmacologia , Etinilestradiol/farmacologia , Norgestrel/farmacologia , Etinilestradiol/administração & dosagem , Feminino , Humanos , Norgestrel/administração & dosagem , Projetos Piloto , Gravidez
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