Autopercepción y uso de suplementos nutricionales en usuarios de gimnasios / Self-Perception and Use of Nutritional Supplements in Gym Users

La insatisfacción con la imagen corporal puede desencadenar preocupación excesiva por la estética conduciendo a una utilización indiscriminada de suplementos nutricionales. Por ello, el objetivo de este estudio fue investigar la relación entre percepción y conformidad de imagen corporal al uso de suplementos nutricionales en usuarios regulares de gimnasios de la región del Biobío, Chile. La investigación corresponde a un estudio analítico transversal realizado en el segundo semestre del año 2018, en el que participaron 262 personas mayores de 18 años. Se observó una asociación estadísticamente significativa entre el uso de suplementos nutricionales y la percepción de la imagen corporal (OR 0,58, IC95%0,34–0,98; p=0,045), y entre el uso de suplementos nutricionales y la conformidad con la imagen corporal (OR 0,43, IC95%0,25–0,75; p=0,003). En conclusión, a mayor disconformidad con la imagen corporal o la presencia de una percepción alterada de ésta, mayor es la probabilidad de consumir suplementos nutricionales. (AU)

Dissatisfaction with body image can trigger excessive concern for aesthetics aspects leading to indiscriminate use of nutritional supplements. Therefore, the objective of this study was to investigate the relationship between the perception and conformity of body image with the use of nutritional supplements in regular users of gyms in the Biobío region, Chile. The research corresponds to a cross-sectional analytical study conducted in the second half of the year 2018, in 262 participants over 18 years old. A statistically significant association between the use of nutritional supplements and the perception of body image (OR 0.58, 95% CI 0.34–0.98; p = 0.045), and between the use of nutritional supplements and conformity with body image (OR 0.43, 95% CI 0.25-0.75; p = 0.003) were observed. In conclusion, to greater disagreement with body image or the presence of an altered perception of it, more likely to consume nutritional supplements. (AU)

Photochemically induced cystic lesion in the rat spinal cord. I. Behavioral and morphological analysis.

The present study describes the production of a spinal cord lesion which is initiated by vascular occlusion resulting from the interaction between the photosensitizing dye erythrosin B and an argon laser beam. The lesion has characteristics similar to those of the central cavity thought to lead to the production of post-traumatic syringomyelia (PTS) in humans. The present study examines the behavioral and morphological characteristics of this injury over a 28-day period. Histological analysis revealed a cavity extending from the dorsal horns to lamina VIII, with some lateral and ventral pathways being spared. The cavity volume reached a maximum 7 days after lesion induction. Behavioral changes were assessed using six different tests of motor and reflex function (motor function, climbing, waterbath, inclined plane, withdrawal to pain, and withdrawal to extension). Lesioned animals exhibited flaccid paralysis for 3-5 days, which resolved afterward. The photochemically induced cavity should provide a reproducible model for examining the effects of cystic spinal cord injury on locomotor and reflex function.

Rat beta-nerve growth factor sequence and site of synthesis in the adult hippocampus.

A rat beta-nerve growth factor (NGF) genomic sequence encoding the entire 3' exon of preproNGF was cloned, and its nucleotide sequence was determined. Rat NGF shows very high homology with other known NGFs in both the prepropeptide and the 3' untranslated regions. The presumptive signal sequence, the cysteine residues important for tertiary structure, possible glycosylation sites, and dibasic amino acids required for proteolytic cleavage to mature NGF are conserved across species. Comparison of the hydrophobicity plots and amino acid sequences revealed an evolutionary divergent domain on the external surface of NGF, which may account for the poor immunologic crossreactivities of the various NGFs. In situ hybridization with a rat-specific oligodeoxynucleotide indicated high levels of NGF mRNA synthesis in both hippocampal granule and pyramidal cell layers. These results are consistent with one role for NGF in the CNS as a neuronally released, retrogradely transported neurotrophic factor for basal forebrain cholinergic neurons.

Simultaneous determination of local cerebral glucose utilization and blood flow by carbon-14 double-label autoradiography: method of procedure and validation studies in the rat.

Validation studies were undertaken to establish a computer-assisted double-label autoradiographic strategy employing [14C]2-deoxyglucose ([14C]2DG) and [14C]iodoantipyrine ([14C]IAP) to measure local CMRglu (LCMRglu) and CBF (LCBF). An organic solvent was used to extract the majority of IAP between first and second film exposures. In contrast to previously published data, all solvents tested produced partial losses of 2DG from tissue, and all allowed 2-6% of IAP to persist even after 5-day washes. Technical-grade chloroform permitted equal retention of unmetabolized and metabolized 2DG. A linear model was established, which was insensitive to the changes in tissue self-absorption that were shown to occur with chloroform extraction. Propagated error in computing tissue [14C]2DG and [14C]IAP was reduced by maximizing IAP extraction (by longer solvent wash times) and by administering 2.5 times as much IAP as 2DG. Fractional 2DG retention was measured in single-label 2DG sections placed on the films, and fractional IAP retention was evaluated by an optimization procedure. With this strategy, double-label values for LCMRglu and LCBF in anesthetized rats agreed with values obtained in matched single-label series to within 5%. The coefficients of variation for the double- and single-label LCMRglu data were virtually identical, whereas the coefficient of variation for double-label LCBF was 1.8 times that of single-label LCBF. The double-label strategy permitted pixel-by-pixel measurement and video display of the LCMRglu/LCBF ratio; the mean value among structures was 0.472 mumol/ml. With proper attention to methodological detail, this double-label strategy shows great promise for routine laboratory application.

Evaluation of transected spinal cord regeneration in the rat.

Rat spinal cords were subjected to a 200 g/cm force acceleration injury at T10. Ten days later, the cords were totally transected at T10 and the rats separated into two groups: group C (controls) had the spinal cord realigned end-to-end; group X had 3 mm trimmed from proximal and distal cord stumps and a semifluid collagen matrix (CM) bioimplant was inserted in the gap. The CM polymerized to a firm gel at body temperature within 2 h. All rats were maintained 90 days posttransection (dpt). At 90 dpt, they were examined for local spinal cord blood flows, somatosensory evoked potentials, and a neurological evaluation. After killing, the cords were processed for electron and light microscopy and monoamine histofluorescence. The results indicated that CM can support the growth of central neurites, fibroblasts, and an adequate anastomotic network of blood vessels. Control scar tissue does not promote the presence of nerve fibers and blood vessels to the extent observed in the CM. Somatosensory evoked potential early waveforms were present in CM-bioimplanted rats but not in controls. No rat regained walking ability at 90 dpt but muscle tone and strength appeared better in CM-implanted than in control rats. We conclude that a CM bridge can provide a well vascularized, relatively nonhostile environment for central neurites and catecholaminergic axons extending from the proximal spinal cord tissue across the CM bridge and into the distal stump.

Local blood flow, oxygen tension, and oxygen consumption in the rat spinal cord. Part 1: Oxygen metabolism and neuronal function.

A reliable and reproducible microelectrode technique provided consistent simultaneous measurements of local spinal cord blood flow (local SCBF), tissue oxygen tension (TO2), and tissue oxygen consumption (TO2C) in the rat. Local SCBF was measured by the hydrogen clearance technique, local TO2 was measured polarographically, and local TO2C was calculated from the declining slope of local TO2 following temporary arrest of local SCBF. Mean local TO2 values varied only slightly between gray and white matter, while local TO2C and SCBF maintained a 3 to 1 ratio between gray and white matter areas. Measurements were also made of these parameters in specific white matter tracts and laminae of Rexed. Local white matter SCBF was relatively homogeneous throughout the ventral, lateral, and dorsal funiculi. Gray matter blood flow was more variable with topography. The highest local SCBF was recorded in areas rich in internuncial neurons. The somatic motor regions had values slightly higher than recorded in sensory regions.

Local blood flow, oxygen tension, and oxygen consumption in the rat spinal cord. Part 2: Relation to segmental level.

Using a reliable and reproducible microelectrode technique, consistent simultaneous measurements of local spinal cord blood flow (SCBF), tissue oxygen tension, and tissue oxygen consumption were made at cervical, thoracic, and lumbar levels in the rat spinal cord. These observations showed that the metabolic state is maintained constant along the cord, despite significant variations in vasculature. The physiological and anatomical aspects of these findings are discussed.

Simultaneous measurement of local blood flow and tissue oxygen in rat spinal cord.

Measurement of local blood flow by hydrogen clearance is a useful technique and is compatible with simultaneous measurement of oxygen tension over long periods. However, existing methods present serious limitations of spatial resolution due to high diffusion rates and other factors. Improved methods permit local measurements in both gray and white matter of the rat spinal cord that correlate well with data from autoradiographic techniques, and indeed distinguish between individual gray matter laminae. Applications of similar methods should be useful in other systems where high spatial resolution is required.

Steady state drug or fluid delivery to injured or transected spinal cord of rats.

Fluids or drugs were delivered to injured or transected spinal cords of rats at a controlled rate and concentration. The technique used a catheter system molded to the shape of the spinal cord and attached to an osmotic minipump reservoir that was subcutaneously by the rats.