Introduction
Frailty is a multicausal syndrome characterized by a decrease in strength, resistance and physiological function, which makes the individual vulnerable and dependent, and increases ...his/her mortality. This syndrome is more prevalent among older individuals, and chronic kidney disease patients, particularly those on dialysis. Dialysis dose is currently standardized for hemodialysis (HD) patients regardless of their age and functional status. However, it has been postulated that the dialysis dose required in older patients, especially frail ones, should be lower, since it could increase their degree of frailty. Then, the purpose of this study was to evaluate if there would be a correlation between the dose of Kt/V and the degree of frailty in a population of adult patients on HD.
Materials and methods
A cross-sectional study with 82 patients on HD in Barranquilla (Colombia) and Lobos (Argentina) was conducted. Socio-demographic and laboratory data, as well as dialysis doses (Kt/V) were recorded and scales of fragility, physical activity, gait and grip strength were applied. Then these data were correlated by a Spearman’s correlation and a logistic regression.
Results
CFS, social isolation, physical activity,
gait speed,
and
prehensile strength tests
were outside the reference ranges in the studied group. No significant correlation was found between dialysis dose and all the above mentioned functional tests. However, a significant and inverse correlation between physical activity and CFS was documented (score − 1.41 (CI − 2.1 to − 0.7).
Conclusion
No significant correlation was documented between Kt/V value and different parameters of the frailty status, but this status correlated significantly and inversely with physical activity in this group. Frailty status in hemodialysis patients was significantly higher in older individuals, although young individuals were not exempt from it.
El filtrado glomerular (FG) es considerado el mejor índice para evaluar la función renal (FR) en la práctica clínica. Durante décadas, se ha utilizado la relación simultanea de concentraciones ...séricas y urinarias de biomarcadores endógenos para su medición; más recientemente, el uso de ecuaciones que estiman el FG a partir exclusivamente de los niveles séricos de algunos biomarcadores. Estas ecuaciones han ganado popularidad tanto en la práctica médica habitual como en estudios epidemiológicos, en distintas poblaciones. Sin embargo, no todas han sido validadas en los diversos escenarios clínicos probables o en poblaciones de edades y etnias diferentes.
Las entidades científicas que suscriben este documento: Sociedad Argentina de Nefrología, Asociación Bioquímica Argentina, Fundación Bioquímica Argentina y Confederación Unificada Bioquímica de la República Argentina, integradas por nefrólogos y bioquímicos, se propusieron realizar un documento de consenso actualizado sobre la utilización del FG, como herramienta de detección de la enfermedad renal crónica (ERC) en Argentina. Para su elaboración se analizó en detalle la bibliografía existente, considerando aspectos de nuestra realidad sanitaria, con lo que se establecieron sugerencias para su uso práctico. El siguiente es un resumen ejecutivo del documento completo generado, dirigido a evaluar la FR en las distintas condiciones clínicas analizadas.
Homocysteine is an emerging new risk factor for cardiovascular disease. It is a thiol compound derived from methionine and involved in two main metabolic pathways: the cycle of activated methyl ...groups, requiring folate and vitamin B12 as cofactors, and the transsulfuration pathway to cystathionine and cysteine requiring vitamin B6 as cofactor. The homocysteine metabolism represents an interesting model of gene-environment interaction. Elevations in homocysteine may be caused by genetic defects in enzymes involved in its metabolism or by deficiencies in cofactor levels. A common polymorphism in the gene coding for the 5, 10-methylene tetrahydrofolate reductase (MTHFR) (C677T, Ala → Val) is associated with a decreased activity of the enzyme due to thermolability. In case of homozygosity for the Val allele, a relative deficiency in the remethylation process of homocysteine into methionine leads to a mild-to-moderate hyperhomocysteinemia, a condition recognized as an independent risk factor for atherosclerosis. The genetic influence of the MTHFR polymorphism on homocysteine levels is attenuated in females in premenopausal age and is not significant in subjects who exhibit serum levels of folate and/or vitamin B12 above the 50th percentile of distribution in the general population. The prevalence of the Val/Val genotype varies among different ethnic groups. It is very low in African populations, whereas in Europe and North America it ranges between 5% and 15%. In Italy an even higher prevalence has been reported in some regions. The question whether the MTHFR polymorphism might be per se an independent contributor to cardiovascular risk is debated. The interaction between this or other genetic factors and environmental/nutritional conditions (i.e. intake of vitamins such as folate) is a key determinant for homocysteine concentrations in healthy conditions as well as in some disease (i.e. in renal disorders). Another example of gene/environment interaction in the field of atherosclerosis is given by the apolipoprotein E polymorphism and its influence in response to diet. The presence of a high prevalence of risk-related allelic variants of such candidate genes within a certain population could serve to locally reinforce the recommendations concerning nutrient intake.
Wall shear stress contributes to the endothelial production of vasoactive mediators, like nitric oxide (NO). Brachial artery vasodilation that follows increased blood flow is regulated by NO release. ...Aim of the present study was to investigate whether resting wall shear stress of the brachial artery is related to flow-mediated vasodilation (FMD) induced by forearm ischemia. Wall shear stress was calculated according to the following formula: Wall shear stress
=
Blood viscosity
×
Blood velocity/Internal diameter. FMD was calculated as percentage change of brachial artery diameter following forearm ischemia. Twenty-seven healthy male subjects were investigated. Peak wall shear stress and FMD were 37.3
±
12.8 dynes/cm
2 and 110.7
±
5.6%, respectively (mean
±
S.D.). In simple regression analyses, age was inversely associated with wall shear stress (
r
=
48,
P
<
0.01) and, marginally, with FMD (
r
=
0.33,
P
=
0.08). Wall shear stress and FMD were directly related (
r
=
0.60,
P
<
0.001). In multiple regression analysis, including wall shear stress, age, blood pressure, lipids, glucose and Body Mass Index as independent variables, wall shear stress was the only variable independently associated with FMD (standardized
β coefficient
=
0.690,
P
⩽
0.005). To avoid the influence of brachial artery size on FMD, the regression analysis was restricted to subjects with similar diameter (
n
=
12). In these subjects wall shear stress continued to be significantly associated with FMD (
r
=
0.69,
P
=
0.01). Our results demonstrate a strong association between resting wall shear stress and FMD in the brachial artery in healthy men in vivo. This association is independent of age and vessel diameter.
Large calderas are among the Earth's major volcanic features. They are associated with large magma reservoirs and elevated geothermal gradients. Caldera-forming eruptions result from the withdrawal ...and collapse of the magma chambers and produce large-volume pyroclastic deposits and later-stage deformation related to post-caldera resurgence and volcanism. Unrest episodes are not always followed by an eruption; however, every eruption is preceded by unrest.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
A common variant in the promoter of the human stromelysin gene, causing reduced enzyme expression, has been associated with the progression of coronary atherosclerosis. On the other hand, increased ...stromelysin activity may promote plaque rupture. The present study was undertaken to investigate the relationship between the genetic variation in the human stromelysin gene promoter and common carotid geometry. Forty-two healthy male subjects without major coronary heart disease risk factors were investigated. The polymorphism in the stromelysin gene promoter was studied through polymerase chain reaction amplification with the use of mutagenic primers. Age, blood pressure, lipids, glucose, viscosity, and body mass index were similar in homozygotes for the 5A allele (5A/5A), heterozygotes (5A/6A), and homozygotes for the 6A allele (6A/6A). Serum matrix metalloproteinase-3 levels did not differ significantly among genotypes. Common carotid diameters and intima-media thickness, measured by noninvasive ultrasonography, were significantly larger in 6A/6A subjects (for respective 6A/6A, 5A/6A, and 5A/5A subjects, diameter at the R wave was 0.63±0.09, 0.55±0.06, and 0.53±0.04 cm mean±SD, P <0.005 by ANOVA; intima-media thickness was 765±116, 670±116, and 630±92 μm mean±SD, P <0.05 by ANOVA). Wall shear stress, calculated as blood velocity×blood viscosity/internal diameter, was significantly lower in 6A/6A subjects (for respective 6A/6A, 5A/6A, and 5A/5A subjects, mean wall shear stress was 10.4±2.9, 13.5±3.5, and 12.6±1.9 dyne/cm mean±SD, P <0.05 by ANOVA).The results demonstrate that the gene polymorphism in the promoter region of stromelysin is associated with structural and functional characteristics of the common carotid artery in healthy male subjects without major risk factors for atherosclerosis. Individuals with the 6A/6A genotype (associated with lower enzyme activity) show a triad of events, namely, increased wall thickness, enlarged arterial lumen, and local reduction of wall shear stress, which might predispose them to atherosclerotic plaque localization.
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