PubMed Health⌕ Search

Biomedical subjects

H Miranda

Publications and source records attributed to H Miranda.

At least 19 recordsLinked to original sources

A prospective study on knee pain and its risk factors.

OBJECTIVES: To evaluate the effects of work-related and individual factors as well as physical activity and sports on the incidence and persistence of knee pain among a working population. DESIGN: Employees of a large Finnish forestry company replied to a questionnaire (a modified version of the Nordic Questionnaire) on musculoskeletal pain and its possible risk factors at the baseline of this study. A cohort of 2122 workers free of knee pain and another cohort of 333 workers with severe knee pain were followed up for one year. The effects of the risk factors on the incidence and persistence of knee pain were studied using multivariable logistic regression models. RESULTS: A total of 214 (10%) workers developed knee pain during the follow-up. Significant predictors of incident knee pain in the multivariable model were higher age, overweight, smoking, and previous knee injuries. Also, working with the trunk forward flexed in kneeling or standing position and physically strenuous work were non-significant predictors of incident knee pain. Of those 333 workers with severe knee pain at baseline, 220 (66%) still reported severe knee pain after one year. Higher age and job dissatisfaction increased the risk of persistent symptoms. General physical exercise and different sports activities did not predict the incidence or persistence of knee pain. CONCLUSIONS: In this large prospective study, the risk factors for self-reported knee pain seemed to be highly similar to the risk factors for knee osteoarthritis (OA) reported in other papers. Age, previous knee injuries, overweight, and knee-straining work were those risk factors, which contributed to the incidence of knee pain. Psychosocial elements of work were more involved in the persistence of the symptoms in the knee.

Adult↗

Physical exercise and musculoskeletal pain among forest industry workers.

The study investigated the relations between physical exercise and musculoskeletal pain among forest industry workers. We studied a population of 3312 Finnish forest industry workers, who replied to a questionnaire survey in 1994 (response rate 77%). The outcome variables in this cross-sectional study were the number of days with pain in the low back, neck, shoulder and knee during the preceding 12 months. Multivariable logistic regression models were used in statistical analyses. Active walkers had more sciatic pain, active volleyball players had more shoulder pain and those who practiced trekking actively had more knee pain than those who practiced these activities less. The risk of shoulder pain was more than three times higher for those who played volleyball actively compared to those who played less. In addition, age, mental stress and work-related physical loading were strongly associated with musculoskeletal pain. When studying the relations between physical exercise and musculoskeletal pain in a working population, it is important to not only detect the general physical activity but also to specify the different modes of exercise. In addition, the other factors which are strongly related to pain (such as mental stress and work-related physical loading) should be taken into account.

Adult↗

A prospective study of work related factors and physical exercise as predictors of shoulder pain.

OBJECTIVES: To evaluate the effects of work related and individual factors as well as physical activity and sports on the incidence and persistence of shoulder pain among forestry workers. METHODS: Workers in a large Finnish forestry company replied to a questionnaire (a modified version of the Nordic questionnaire) on musculoskeletal pain and its possible risk factors for 4 consecutive years 1992-5. This 1 year follow up study covers the time 1994-5. Year 1994 was chosen as baseline because in that year the questionnaire contained for the first time more detailed questions about different sports. The response rate in 1995 was 90%. The effects of the predictors on 1 year incidence and persistence of shoulder pain were studied with multivariate logistic regression modelling. RESULTS: At baseline, 2094 subjects had been free of shoulder pain during the preceding 12 months. After 1 year, 14% (n=285) reported having mild or severe shoulder pain. Higher age, obesity, and mental stress as well as physically strenuous work and working with trunk forward flexed or with a hand above shoulder level increased the risk of incident shoulder pain. Of the different sports activities, dancing increased the risk of incident pain whereas jogging decreased the risk significantly. Of those 419 workers who had severe shoulder pain at baseline, 55% (n=230) still had severe pain 1 year later. Higher age, overload at work, and working with a hand above shoulder level increased the risk of persistent severe shoulder pain whereas cross country skiing and general sports activity decreased the risk. CONCLUSION: Our results support the current view that shoulder pain is the result of many factors, including occupational and individual factors. In this longitudinal study, physical work with a heavy load, awkward work postures, mental stress, and obesity were the risk factors at which preventive measures could be aimed. As a new finding, physical exercise had more protective than impairing effects on the shoulders.

Adult↗

A survey on hepatitis A in Portuguese children and adolescents.

In the early 1980s, Portugal could be classified as a highly endemic area for hepatitis A. However, marked economic and sanitary improvements took place during the following years. In this study we evaluated the temporal trends in the prevalence of hepatitis A in children and adolescents, to identify risk factors for the infection. The study sample included students aged 6 to 19 years (n=999), attending public and private schools. All randomly selected participants gave information on social, demographic, clinical and behavioural variables, but only 667 (67.4%) agreed to provide a blood sample for the determination of total and immunoglobulin M (IgM) anti-hepatitis A virus (HAV) antibodies. The prevalence of anti-HAV-positive subjects was 27.9%, with a linear age-related increase (r=0.87, P=0.011) from 20.9% at 6-7 years to 37.8% at 18-19 years. The crowding index and the level of maternal education were the only independent predictors of hepatitis A infection. This study showed a clear decrease in hepatitis A prevalence in our population. However, it remains a common infection in Portugal, easily acquired early in life and associated with indicators of poverty.

Adolescent↗

[Sensory characterization of lupin pudding using surface response methodology].

Full fat sweet lupin flour (Lupinus albus c.v. Multolupa) with 39.6% protein and 13.0% lipid content, and carrageenan were used to incorporate them to commercial pudding formula with the specific purpose to prepare an optimized pudding for diabetic people. Using response surface methodology, several experimental pudding trails were prepared and sensorially assessed to optimize the variables that may influence the overall sensory quality of pudding meals. Different concentrations of lupin flour and carrageenan were tested simultaneously at three levels each parameter, requiring nine combinations to be analyzed for a panel of eleven trained judges. Appearance, aroma, taste, color, texture were tested to determine total sensory quality using a composite scoring test. It was concluded that appropriate concentration of lupin flour range from 7% to 11%, and carrageenan from 0.4% to 0.5% to be added to the pudding formulation. This result was confirmed by hedonic test of acceptability.

Diet, Diabetic↗

Chronic ethanol administration induces tolerance to morphine and to beta-endorphin responses in the rat vas deferens.

The possibility was investigated that ethanol, chronically administered, might produce changes in the opioid receptors located on the sympathetic nerves of the rat vas deferens. Administration of ethanol, 3-9 g/kg per day for six days, resulted in tolerance to the hypnotic effects induced by ethanol (4 g/kg i.p.) and pentobarbital (35 mg/kg i.p.). Ethanol administration also resulted in tolerance to the effects of morphine and beta-endorphin on the muscular twitch evoked in the rat vas deferens by neuronal stimulation. In contrast, chronic ethanol did not significantly change the effects on vas deferens contractions induced by exogenous bioamines such as noradrenaline and dopamine and by acetylcholine. These results suggest that ethanol and opioids have certain biochemical mechanisms in common which might express themselves at the level of prejunctional components involved in the modulation of neurotransmitter action in the rat vas deferens.

Animals↗

Cholinergic transmission in vas deferens.

Prazosin, haloperidol, propranolol or timolol had no effect on the electrically evoked muscular twitch. Atropine was able to antagonize competitively acetylcholine (pA2 = 9.29 +/- 0.30). The muscular twitch of the Octodon degus vas deferens was only partially abolished by atropine (53.2 +/- 0.72). The present results can be interpreted assuming that the Octodon degus vas deferens has one component muscarinic in its innervation.

Acetylcholine↗

Biogenic amines and beta-endorphin responses in the rat vas deferens.

1. Recent studies have demonstrated that activation of opioid peptide receptor by beta-endorphin results in a change of bioamines in peripheral tissues. 2. The present results could be interpreted assuming that the action of beta-endorphin, on the smooth muscle of the isolated rat vas deferens, is independent of catecholaminergic, cholinergic and tryptaminergic neurotransmission. 3. There is evidence that it is through a specific opioid 'epsilon-receptor' which have been shown a high degree of affinity for beta-endorphin.

Animals↗

Excitability ot beta-endorphin, morphine and catecholamines of the vas deferens of the rat at different stages of development.

The effect of beta-endorphin and morphine on neuromuscular twitching of the vas deferens was examined in rats of 10-120 days of age. The maximal tension developed by the smooth muscle was markedly dependent on the age of the rat and on the kind of stimulus applied. The potency of beta-endorphin to inhibit the electrically induced twitching or of catecholamines to induce muscle contraction was not significantly altered by development of the animal. The excitatory action of morphine showed significant variations in activity reaching maximal sensitivity at about two months of age. Age or the onset of puberty do not significantly modify the sensitivity of the vas deferens to beta-endorphin, the peptide may play the role of modulating adrenergic transmission.

Aging↗

Interactions between morphine and the opioid-like peptides in the rat vas deferens.

1 Morphine, methadone, levorphanol, pethidine, etonitazene and related morphine-like alkaloids produced an increase in the electrically-evoked muscular contraction of the rat vas deferens. In contrast, the enkephalins and beta-endorphin caused inhibition of the twitching. 2 The concentration of beta-endorphin required to inhibit by 50% the muscular twitch was about 50 to 100 times less than that of the enkephalins. 3 Pretreatment of the vasa with morphine antagonized the inhibition of the neuromuscular transmission caused by either beta-endorphin or enkephalin. 4 Conversely, pretreatment with beta-endorphin sensitized the vasa to the increase in twitch tension caused by morphine. 5 Morphine did not alter the sensitivity to exogenously administered noradrenaline, dopamine or potassium.

Animals↗

Non-competitive-non-equilibrium alpha-adrenoceptor blocking properties of N-benzyl iodoacetamide, betsamide.

N-Benzyl iodoacetamide, betsamide, at 10 mg kg-1 i.v. blocked the hypertensive and contractile responses of the nictitating membrane of the cat to adrenaline. The blockade had a lag period before full development. Pretreatment of cats with betsamide for 7 or 18 h showed a non-equilibrium type of alpha-adrenoceptor blockade. The responses of the nictitating membrane to adrenaline were markedly depressed and did not recover after high doses of adrenaline. In the same cats, adrenaline caused a profound hypotension. The effect of betsamide lasted for at least 72 h. In the rat isolated vas deferens, 3 X 10(-5) M betsamide non-competitively blocked the contractile responses to noradrenaline; the adrenoceptor blockade was less effective when betsamide was applied with noradrenaline. The blockade lasted for more than 24 h, and was not reversible after extensive washing. Betsamide antagonized the contractile effects of carbachol and 5-hydroxytryptamine on the rat vas deferens, but not the beta-responses of the guinea-pig trachea to adrenaline and isoproenaline. Results are discussed in relation to a probable mechanism of action.

Adrenergic alpha-Antagonists↗

Effects of oxypertine on the isolated vas deferens of the rat.

1 The isolated vas deferens of the rat was used to examine the peripheral action of oxypertine, a psychotropic-anxiolytic drug. 2 Oxypertine (4.4 X 10(-10) M to 2.6 X 10(-5) M) antagonized competitively the effects of noradrenaline (pA2 = 7.2), 5-hydroxytryptamine (pA2 = 8.6) and dopamine (pA2 = 9.8). 3 Oxypertine (8.8 X 10(-9) M to 2.6 X 10(-5) M) antagonized the effects of low concentrations of acetylcholine and enhanced the contractions elicited by high concentrations of acetylcholine. 4 The contractions evoked by transmural stimulation of the vas deferens were reduced by oxypertine. 5 Oxypertine failed to antagonize the responses to potassium chloride. 6 These findings are compared with the effects of other antidepressant drugs.

Acetylcholine↗