Survey of caffeine levels in retail beverages in Portugal.

The caffeine content of 85 retail beverage samples purchased from local supermarkets between 1995 and 2004 was determined. The potential intake of caffeine through the consumption of these beverages (but excluding coffee) was estimated for students of the University of Coimbra, Portugal. The caffeine content of the beverages ranged from 47.5 to 282.5 mg l(-1) for teas, from 20.1 to 47.2 mg l(-1) for tea extracts samples, and from 80.7 to 168.7 mg l(-1) for cola soft drinks. Caffeine was not completely absent from caffeine-free colas, and energy drinks had a far greater caffeine content than regular drinks, ranging from 21 to 2175 mg l(-1). Soft drinks were consumed by 72% of the individuals, although 14% of the survey participants did not drink any of the different types of the beverages studied. Contrary to expectations for this age group, no consumptions of energy drinks was reported. Daily caffeine intake was estimated to range from 4.7 to 200 mg day(-1), but with only 5% reporting a daily intake around 200 mg caffeine. Cola-type beverages were an important dietary source of caffeine for the population studied. Statistical differences in the caffeine intake between the male and female populations were found, with p = 0.014, being higher for the male population. Of the beverages studied, cola-type drinks showed statistical differences for the male population, p = 0.03, and tea showed statistical differences for female population p = 0.013, respectively.     

Can the ventilatory equivalent for carbon dioxide predict the severity of functional impairment in patients with cardiac insufficiency?

OBJECTIVE: To evaluate whether the changes in the ventilatory equivalent for carbon dioxide (VE/VCO2), during the early stages of cardiopulmonary exercise testing, can predict maximal oxygen consumption (VO2max) in patients with chronic heart failure. METHODS: We studied 38 patients (30 males, mean age 56 +/- 11 years) with chronic heart failure. All patients performed maximal symptom limited, treadmill exercise test with breath-by-breath respiratory gas analysis. They were divided in two groups according to their maximal oxygen consumption (group I-VO2max above 14 ml/kg/min and group II-VO2max below 14 ml/kg/min). In both groups, we analysed VE/VCO2 at rest, at the anaerobic threshold (AT) and at peak exercise, and the percentage of VE/VCO2 reduction from rest to AT. RESULTS: Eleven patients had a VO2max below 14 ml/kg/min (group II). At rest VE/VCO2 = 53 +/- 13 in group II versus 47 +/- 10 in group I (p = 0.048), at the AT VE/VCO2 = 46 +/- 12 in group II versus 36 +/- 7 in group I (p = 0.001) and at peak exercise VE/VCO2 = 46.2 +/- 13 in group II versus 36.2 +/- 6 in group I (p = 0.0002). There was a 24% reduction in the VE/VCO2, from rest to AT in group I, compared to a 16% reduction in group II (p = 0.004). A reduction in the VE/VCO2 from rest to AT less than 16% predicted a VO2max below 14 ml/kg/min with a sensitivity of 60% and a specificity of 93%. CONCLUSIONS: Patients with severe functional impairment have higher values of VE/VCO2 in all exercise stages. A reduction of VE/VCO2 from rest to anaerobic threshold of less than 16% is a high specific predictor of a VO2max below 14 ml/kg/min.     

Comparative affective reactivity of different types of communication disturbances in schizophrenia.

Twenty-nine schizophrenic outpatients provided speech samples on affectively positive and negative topics. These samples were assessed for several different types of communication failures by using the Communication Disturbances Index. Frequencies of overinclusive references, ambiguous word meanings, and ambiguous referents increased in the affectively negative condition; frequencies of missing referents and instances of syntactic unclarity did not change across affective conditions. Degree of overall affective reactivity of speech was associated with severity of the core positive schizophrenic syndrome. These findings support the idea that different types of schizophrenic communication disturbances are associated with different underlying pathophysiological processes, that some are more reactive to affect than others, and that affective reactivity of these symptoms is associated with the positive schizophrenic process. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The effects of a health promotion-health protection intervention on behavior change: the WellWorks Study

OBJECTIVES: This study assessed the effects of a 2-year integrated health promotion-health protection work-site intervention on changes in dietary habits and cigarette smoking. METHODS: A randomized, controlled intervention study used the work site as the unit of intervention and analysis; it included 24 predominantly manufacturing work sites in Massachusetts (250-2500 workers per site). Behaviors were assessed in self-administered surveys (n = 2386; completion rates = 61% at baseline, 62% at final). Three key intervention elements targeted health behavior change: (1) joint worker-management participation in program planning and implementation, (2) consultation with management on work-site environmental changes, and (3) health education programs. RESULTS: Significant differences between intervention and control work sites included reductions in the percentage of calories consumed as fat (2.3% vs 1.5% kcal) and increases in servings of fruit and vegetables (10% vs 4% increase). The intervention had a significant effect on fiber consumption among skilled and unskilled laborers. No significant effects were observed for smoking cessation. CONCLUSIONS: Although the size of the effects of this intervention are modest, on a populationwide basis effects of this size could have a large impact on cancer-related and coronary heart disease end points.     

Renovascular arterial hypertension. From physiopathology to therapy

Understanding the pathophysiology, diagnosis, and management of renovascular hypertension (RVH) is of paramount importance due to the severity of hypertension (HT) and renal insufficiency (RI). Moreover, adequate treatment by surgery and/or endovascular intervention can improve HT and revert RI. The comprehension of the pathophysiology of RVH had its origin on the experiments of Goldblatt which led to the recognition of the renin dependent, volume dependent, and mixed types. A continuum seems to exist, from an acute phase, supported by the endocrine renin angiotensin aldosterone system, evolving towards a chronic phase sustained by the local renin angiotensin system. The involved vasoconstrictor and mitogenic mechanisms may contribute to the arterial remodeling. The most common forms of pathology, i.e. atherosclerosis, fibromuscular dysplasia (FD), and Takayasu's arteritis, and their natural history, are described. The prevalence of RVH, ranging from 0.2% to more than 25%, depending on the clinical situation, is evidenced. Clinical symptoms and signs and the most important diagnostic tests are pointed out: functional tests (captopril test, postcaptopril renography, scintigraphy, and renin determinations) and anatomical tests (intravenous digital angiography and intrarterial angiography). New imaging techniques are also referred. A diagnostic work-up based on the index of clinical suspicion is described. The therapeutic goal is the resolution of the two main problems of RVH: hypertension and ischemic nephropathy. Revascularization is becoming mandatory either by percutaneous transluminal angioplasty mostly for FD and atheromatous non-ostial stenoses, or by surgery, which is preferred for patients with ostial or peripheral stenoses, aneuryms, occlusions and concomitant aortic disease. A better knowledge of RVH allows, not only diagnosis and treatment of one of the most frequent types of secondary hypertension, but also the control of the resulting ischemic nephropathy.     

Possible role of an adrenal parasite reservoir in the pathogenesis of chronic Trypanosoma cruzi myocarditis

A non-parametric estimator of the AIDS survival time (after developing AIDS) is computed for the AIDS data set from the US Air Force (USAF). Survival times are unobservable. They are censored by the screening mechanism. The Armstrong Laboratory's Epidemiologic Research Division maintains data on over 954 active duty US Air Force (USAF) individuals who tested positive for human immunodeficiency virus (HIV) antibodies. Many have been clinically evaluated seven times since 1986. The HIV-positive individual is classified in seven stages of the disease complex as time progresses. Exact times of transition from one stage to the next are unknown. It is known that transition occurred between two consecutive evaluations. The aim of this study is to analyse distributions of the times that individuals spend in each stage of the HIV disease complex. We will discuss methods used to obtain non-parametric estimators of the distribution of times that individuals spend in stage 6. Finally, it is hoped to model the median time spent in each stage of the disease. This, along with incidence and separation data, will allow the prediction of the impact of HIV disease on USAF individuals and medical care systems.     

Length distribution of aluminum etch tunnels

A model was derived for the length distribution of aluminum etch tunnels, based on an assumed constant death rate per unit length. Both active and dead tunnels were accounted. The model gives reasonable fits to measured tunnel length distribution data with two adjustable parameters, the death rate per unit length and the number of active tunnels. The death rate parameter has a value of about 2% of tunnels dying per m of growth length for the set of experimental data. The numbers of active and dead tunnels appear to be consistent with other tunnel measurements.     

Patterns of DNA synthesis and mitotic activity during the intermoult of Daphnia

Among insects, the epidermal cell cycle pattern is related to the type of ontogenetic development. In taxa undergoing complete metamorphosis, cells are commonly maintained in the G2 stage of interphase between bouts of cell division. In crustaceans, as in insects exhibiting incomplete metamorphosis, it is believed that cells ordinarily remain in G1 for much of the intermoult, with DNA replication occurring late in the moult cycle followed closely by cell division. The present study reveals a differing pattern of epidermal cell division in two distantly related members of the cladoceran crustacean genus Daphnia. Cell cycle kinetics were examined in the last juvenile instar of each species using DNA content determinations and estimates of mitotic frequency. These analyses confirm that each epidermal cell possessed the diploid DNA amount, completed a single cell cycle, and remained in G1 for the majority of the instar. However, DNA replication occurred shortly after moulting and was followed by intense mitotic activity so that cell proliferation was restricted to a short period soon after ecdysis. Cell densities during the instar increased by approximately 60 and 100% for D. pulex and D. magna, respectively.     

Brief, high-frequency stimulation of the corticomedial amygdala induces a delayed and prolonged increase of aggressiveness in male Syrian golden hamsters.

Brief 200-Hz stimulation of the corticomedial amygdala (CMA) increases the aggressiveness of male Syrian golden hamsters for about 30 min; the effect peaks 10–15 min after stimulation. This effect is sensitive to stimulation amplitude and frequency. Stimulation at the parameters that reduce attack latency increases flank marking but does not affect copulation latency or general activity. Immunocytochemical analysis suggests that stimulation effects may be coupled to c-fos expression and that unilateral stimulation has bilateral effects. CMA stimulation effects appear to mimic part of the time course of behaviorally induced attack priming. The temporal persistence of aggression may result from long-term potentiation-like changes within CMA-related neural circuitry. (PsycINFO Database Record (c) 2010 APA, all rights reserved)