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Impairment Secondary (impairment + secondary)

Distribution by Scientific Domains
Medical Sciences100%

Selected Abstracts

Collagen Metabolism Is Markedly Altered in the Hypertrophic Cartilage of Growth Plates from Rats with Growth Impairment Secondary to Chronic Renal Failure

JOURNAL OF BONE AND MINERAL RESEARCH, Issue 3 2001
Jesús Álvarez
Abstract Skeletal growth depends on growth plate cartilage activity, in which matrix synthesis by chondrocytes is one of the major processes contributing to the final length of a bone. On this basis, the present work was undertaken to ascertain if growth impairment secondary to chronic renal insufficiency is associated with disturbances of the extracellular matrix (ECM) of the growth plate. By combining stereological and in situ hybridization techniques, we examined the expression patterns of types II and X collagens and collagenase-3 in tibial growth plates of rats made uremic by subtotal nephrectomy (NX) in comparison with those of sham-operated rats fed ad libitum (SAL) and sham-operated rats pair-fed with NX (SPF). NX rats were severely uremic, as shown by markedly elevated serum concentrations of urea nitrogen, and growth retarded, as shown by significantly decreased longitudinal bone growth rates. NX rats showed disturbances in the normal pattern of chondrocyte differentiation and in the rates and degree of substitution of hypertrophic cartilage with bone, which resulted in accumulation of cartilage at the hypertrophic zone. These changes were associated with an overall decrease in the expression of types II and X collagens, which was especially marked in the abnormally extended zone of the hypertrophic cartilage. Unlike collagen, the expression of collagenase-3 was not disturbed severely. Electron microscopic analysis proved that changes in gene expression were coupled to alterations in the mineralization as well as in the collagen fibril architecture at the hypertrophic cartilage. Because the composition and structure of the ECM have a critical role in regulating the behavior of the growth plate chondrocytes, results obtained are consistent with the hypothesis that alteration of collagen metabolism in these cells could be a key process underlying growth retardation in uremia. [source]

Frontal-lobe mediated behavioral dysfunction in amyotrophic lateral sclerosis

EUROPEAN JOURNAL OF NEUROLOGY, Issue 1 2010
M. Witgert
Background:, Cognitive impairment secondary to frontal lobe atrophy exists in 40,60% of Amyotrophic Lateral Sclerosis (ALS) cases. We aimed to determine the prevalence of frontal-lobe mediated behavioral impairment in (ALS) and to ascertain its relationship to cognitive impairment. Methods:, Two-hundred and twenty five patients diagnosed with sporadic ALS were evaluated for behavioral dysfunction using the Frontal Systems Behavior Scale (FrSBe), a validated measure used to examine frontal-lobe mediated behaviors, specifically apathy, executive dysfunction and disinhibition; a total behavior score is also provided. Additionally, a subset of patients also underwent a comprehensive neuropsychological evaluation. Results:, Changes in the total FrSBe scores were observed in 24.4% of the patients and 39.6% of the patients had impairment in at least one behavioral domain with symptoms of Apathy being the most common (31.1%). Cognitively impaired ALS patients had worse total (P = 0.05) and apathy scores (P < 0.01); however, behavioral dysfunction was also present in 16% of the cognitively intact patients. Half of the behaviorally intact patients exhibited cognitive impairment. Significant correlations were observed for performance on certain neuropsychological tests (Animal fluency, Block Design, Logical Memory I and Verbal Series Attention Test) and severity of behavioral dysfunction on certain FrSBe sub scores. Conclusions:, Frontal-lobe mediated behavioral dysfunction appears to be common in ALS. Cognitively impaired ALS patients had greater behavioral dysfunction. Recognition of behavioral and cognitive dysfunction may assist health-care providers and care-givers recognize changes in decision-making capacity and treatment compliance of patients with ALS. [source]

The neuropsychology of ecstasy (MDMA) use: a quantitative review

HUMAN PSYCHOPHARMACOLOGY: CLINICAL AND EXPERIMENTAL, Issue 7 2007
Konstantine K. Zakzanis
Abstract A growing number of empirical studies have found varying neuropsychological impairments associated with use of 3,4-methylenedioxymethamphetamine (MDMA) use. We set out to determine to what extent neuropsychological abilities are impaired in MDMA users. To do so, meta-analytical methods were used to determine the magnitude of neuropsychological impairment in MDMA users across pre-specified cognitive domains. We found that cognitive impairment secondary to recreational drug use may result in what might be described as small-to-medium effects across all cognitive domains with learning and memory being most impaired. We also found that total lifetime ingestion of MDMA appears to be negatively associated with performance on tasks ranging from attention and concentration to learning and memory. Implications and limitations of these findings are discussed. Copyright © 2007 John Wiley & Sons, Ltd. [source]

Collagen Metabolism Is Markedly Altered in the Hypertrophic Cartilage of Growth Plates from Rats with Growth Impairment Secondary to Chronic Renal Failure

JOURNAL OF BONE AND MINERAL RESEARCH, Issue 3 2001
Jesús Álvarez
Abstract Skeletal growth depends on growth plate cartilage activity, in which matrix synthesis by chondrocytes is one of the major processes contributing to the final length of a bone. On this basis, the present work was undertaken to ascertain if growth impairment secondary to chronic renal insufficiency is associated with disturbances of the extracellular matrix (ECM) of the growth plate. By combining stereological and in situ hybridization techniques, we examined the expression patterns of types II and X collagens and collagenase-3 in tibial growth plates of rats made uremic by subtotal nephrectomy (NX) in comparison with those of sham-operated rats fed ad libitum (SAL) and sham-operated rats pair-fed with NX (SPF). NX rats were severely uremic, as shown by markedly elevated serum concentrations of urea nitrogen, and growth retarded, as shown by significantly decreased longitudinal bone growth rates. NX rats showed disturbances in the normal pattern of chondrocyte differentiation and in the rates and degree of substitution of hypertrophic cartilage with bone, which resulted in accumulation of cartilage at the hypertrophic zone. These changes were associated with an overall decrease in the expression of types II and X collagens, which was especially marked in the abnormally extended zone of the hypertrophic cartilage. Unlike collagen, the expression of collagenase-3 was not disturbed severely. Electron microscopic analysis proved that changes in gene expression were coupled to alterations in the mineralization as well as in the collagen fibril architecture at the hypertrophic cartilage. Because the composition and structure of the ECM have a critical role in regulating the behavior of the growth plate chondrocytes, results obtained are consistent with the hypothesis that alteration of collagen metabolism in these cells could be a key process underlying growth retardation in uremia. [source]