Atividade física e as lipoproteinas plasmáticas / Physical activity and plasmatic lipoproteins

Os níveis séricos das lipoproteinas plasmáticas têm sido, já há alguns anos, o foco das pesquisas que preocupam-se em estabelecer os fatores de risco para patologias ateroescleróticas. Com esse propósito, verificou-se que a atividade física é capaz de promover alterações metabólicas que causam um aumento da concentraçäo de lipoproteínas de alta densidade (HDL) e de suas subfraçöes. Além disso, ocorre diminuiçäo de lipoproteínas de baixa densidade (LDL) e lipoproteínas de muito baixa densidade (VLDL). Essas alteraçöes estäo profundamente relacionadas com a diminuiçäo dos acidentes vasculares por diminuiçäo dos níveis de coleterol e triglicerídeos. Os autores procuraram mostrar as alteraçöes ocorridas com as lipoproteínas plasmáticas em decorrência de mudanças na atividade das enzimas lipase lipoprotéica (LPL), lecitina: colesterol acil transferase (LCAT), lipase triglicerídeo hepática (HTGLA) e proteína transferidora de ésteres de colesterila (CETP)

Risk factors for cortical, nuclear, posterior subcapsular and mixed cataract: a case-control study.

A case-control study was conducted to evaluate risk factors for cortical, nuclear, posterior subcapsular and mixed cataract. The 385 cases and 215 controls (age range 40-75 yrs) included in the study underwent a complete ophthalmological examination and laboratory blood tests, and were interviewed about behavioral variables, environmental exposure and their medical history. Lens opacity was classified using the 'Lens Opacity Classification System II' (LOCS II). On multivariate analysis, the risk factors for cortical cataract were the presence of diabetes for more than five years (OR = 3.7) and increased serum K+ and Na+ levels. A history of surgery under general anesthesia and the use of sedative drugs were associated with reduced risk (OR = 0.4). Posterior subcapsular cataract was associated with the use of steroids (OR = 18.2) and diabetes (OR = 8.1), and nuclear cataract with calcitonin (OR = 5.7) and milk intake (OR = 0.25). Mixed cataract was associated with a history of surgery under general anesthesia (OR = 0.5). Some of these results are consistent with the findings of similar studies performed in different geographical areas, others are not. The results suggest a possible role of electrolyte imbalance in the development of senile cataract.

Relationship between morphometric optic disc parameters, sex and axial length.

Optic disc correlations were evaluated in normal eyes by means of computer-aided morphometry. Two hundred and thirty-five subjects (144 women and 91 men) entered the study. One eye per patient was randomly chosen for statistical analysis. Disc area (P < 0.05) and axial length (P < 0.0001) were statistically different between sexes. There was a correlation between axial length and both disc area (r for females = 0.55, P < 0.00001; r for males = 0.35, P < 0.0007) and refraction (r for females = 0.40, P < 0.00001; r for males = 0.50, P < 0.00001). The main findings of this investigation were that disc area is greater in male than in female eyes (thus clinically confirming the Ishi's and Quigley's previous observations of autopsy eyes) on the basis of axial length difference between the two sexes, and that disc size correlated with axial length. Disagreements in disc measurements reported in previous studies may be caused by differences in the male/female ratios of their samples.

Trends in cataract surgery in Milan (Italy) from 1956 to 1987. Relationship to age and visual acuity.

In order to test whether the mean age at cataract surgery has changed over the course of the last 30 years, a hospital series of 5443 patients undergoing cataract extraction between 1956 and 1987 is reviewed. All cases attended the same University Eye Clinic of Milan and most were resident in the same geographical area. Cases with macular or optic nerve diseases were excluded. Results show that mean age at cataract surgery progressively increased from 67.5 to 71.5 years (slope = +0.096 years of age per year, p = 0.0001) as did visual acuity at surgery (patients with visual acuity levels greater than or equal to 1/10 at time of cataract surgery rose from 3.2% to 47.9%). These results can be interpreted in terms of a change in age composition of the Italian population, improved access to health services for the elderly, and an improvement in surgical and rehabilitation techniques.