Highway paving in the southwestern Amazon alters long-term trends and drivers of regional vegetation dynamics.

Infrastructure development, specifically road paving, contributes socio-economic benefits to society worldwide. However, detrimental environmental effects of road paving have been documented, most notably increased deforestation. Beyond deforestation, we hypothesize that road paving introduces "unseen" regional scale effects on forests, due to changes to vegetation dynamics. To test this hypothesis, we focus on the tri-national frontier in the southwestern Amazon that has been subject to construction of the Inter-Oceanic Highway (IOH) between 1987 and 2010. We use a long-term remotely sensed vegetation index as a proxy for vegetation dynamics and combine these with field-based socio-ecological data and biophysical data from global datasets. We find 4 areas of shared vegetation dynamics associated with increasing extent of road paving. Applying Dynamic Factor Analysis, an exploratory dimension-reduction time series analysis technique, we identify common trends and covariates in each area. Common trends, indicating underlying unexplained effects, become relatively less important as paving increases, and covariates increase in importance. The common trends are dominated by lower frequency signals possibly embodying long-term climate variability. Human-related covariates become more important in explaining vegetation dynamics as road paving extent increases, particularly family density and travel time to market. Natural covariates such as minimum temperature and soil moisture become less important. The change in vegetation dynamics identified in this study indicates a possible change in ecosystem services along the disturbance gradient. While this study does not include all potential factors controlling dynamics and disturbance of vegetation in the region, it offers important insights for management and mitigation of effects of road paving projects. Infrastructure planning initiatives should make provisions for more detailed vegetation monitoring after road completion, with a broader focus than just deforestation. The study highlights the need to mitigate population-driven pressures on vegetation like family density and access to new markets.

Influence of age and gender on complexity measures for short term heart rate variability analysis in healthy subjects.

Short-term heart rate variability (HRV) analyses (less than 30 min) are suitable for ambulatory care and patient monitoring and can provide an almost immediate test result. Short-term 5 min HRV indices from nonlinear dynamics were determined from 782 females and 1124 males from the KORA S4 database. We applied various fractal and complexity measures with focus on entropies and investigated the influence of age in terms of five age decades (25-34, 35-44, 45-54, 55-64 and 65-74 years) and gender on these HRV indices. The analyses revealed significant modifications of the indices especially by age but partly also by gender especially in the younger groups. These results should be considered in future studies applying nonlinear dynamics, especially if major age and gender differences between the investigated groups are expected.

Short-term heart rate variability--age dependence in healthy subjects.

Heart rate variability (HRV) analysis is an established method to characterize the autonomic regulation and is based mostly on 24h Holter recordings. The importance of short-term HRV (less than 30 min) for various applications is growing consistently. Major reasons for this are the suitability for ambulatory care and patient monitoring and the ability to provide an almost immediate test result. So far, there have been only a few studies that provided statistically relevant reference values for short-term HRV. In our study, 5 min short-term HRV indices were determined from 1906 healthy subjects. From these records, linear and nonlinear indices were extracted. To determine general age-related influences, HRV indices were compared from subjects aged 25-49 years with subjects aged 50-74 years. In a second approach, we examined the development of HRV indices by age in terms of age decades (25-34, 35-44, 45-54, 55-64 and 65-74 years). Our results showed significant variations of HRV indices by age in almost all domains. While marked dynamics in terms of parameter change (variability reduction) were observed in the first age decades, in particular the last two age decades showed certain constancy with respect to the HRV indices examined.

[Multimorbidity and successful aging: the population-based KORA-Age study]. / Multimorbidität und erfolgreiches Altern: Ein Blick auf die Bevölkerung im Rahmen der KORA-Age-Studie.

BACKGROUND: The objective of the KORA-Age research consortium is to assess the determinants and consequences of multimorbidity in the elderly and to look into reasons for successful aging in the general public. PATIENTS AND METHODS: In the KORA-Age cohort study 9,197 persons were included who where born in the year 1943 or before and participants of previous KORA cohort studies conducted between 1984 and 2001 (KORA: Cooperative Health Research in the Region of Augsburg). The randomized intervention study KORINNA (Coronary infarct follow-up treatment in the elderly) tested a nurse-based case management program with 338 patients with myocardial infarct and included an evaluation in health economics. RESULTS: A total of 2,734 deaths were registered, 4,565 participants submitted a postal health status questionnaire and 4,127 participants were interviewed by telephone (response 76.2% and 68.9% respectively). A gender and age-stratified random sample of the cohort consisting of 1,079 persons took part in a physical examination (response 53.8%). CONCLUSION: The KORA-Age consortium was able to collect data in a large population-based sample and is contributing to the understanding of multimorbidity and successful aging.

Agenesia dental. Revisión bibliográfica y reporte de dos casos clínicos / Dental agenesis. Review of the literature and report of two cases

La agenesia dental constituye la anomalía más común del desarrollo craneofacial. El propósito de este reporte es presentar una breve revisión de literatura acerca de esta condición clínica, la cual incluye: terminología, etiología, prevalencia, síndromes y anomalías dentales asociadas; complementado con la presentación de dos casos clínicos completos. En Colombia no hay estudios suficientes que permitan concluir las causas genéticas de esta patología, por lo que se requieren mayores investigaciones al respecto.

Selective contribution of diabetes and other cardiovascular risk factors to cardiac autonomic dysfunction in the general population.

Both cardiac autonomic dysfunction adn cardiovascular risk factors are related to and excess risk of mortality. We sought to determine whether the major cardiovascular risk factors are associated with diminished heart rate variability (HRV), prolonged QTc interval, or increased QT dispersion (QTD). Male (n = 1030) and female (n = 957) subjects, aged 55-74 years, who participated in the population-based MONICA Augsburg survey 1989/90 were assessed for the presence of cardiovascular risk factors such as diabetes, hypertension, obesity, dyslipidemia, smoking, and low physical activity. Lowest quartiles for time domain indexes of HRV (SD of R-R intervals [SDNN], max-min difference), QTc > 440 ms, and QTD > 60 ms determined from 12-lead resting ECG were used as cutpoints. In men, after adjustment for age and alcohol consumption, significant independent determinants for the lowest quartiles of SDNN were diabetes, obesity, and smoking. Independent contributors to prolonged QTc were hypertension, obesity, smoking, and low physical activity, whereas for increased QTD it was only hypertension. In women, diabetes was the only contributor to low SDNN, and hypertension was the only determinant of prolonged QTc. In conclusion, diabetes is the primary determinant of reduced HRV in the general population, while hypertension is the primary contributor to prolonged QTc in both sexes. However, obesity and smoking contribute to autonomic dysfunction in men but not women. Thus, a selectivity and sex-related differences exist among the various cardiovascular risk factors as to their influence on autonomic dysfunction.

Inverse covariation of spectral density and correlation dimension in cyclic EEG dynamics of the human brain.

The responsiveness or excitability of the central nervous system (CNS) to external or internal stimuli is systematically altered corresponding to transient changes of the EEG background activity, mainly in the alpha range. We hypothesise that a transient alpha power increase is due to an underlying increase in synchronisation or coupling strength between various neuronal elements or cortical networks. Consequently, the 'network' of the CNS may be more ordered and, hence, less complex in the case of high spectral density, and vice versa. The goals of the present paper are (1) to prove the inverse covariation between spectral density and correlation dimension for a set of human EEG data, (2) to falsify the null hypothesis that the observed relationship is a random one, and (3) to propose a neuronal approach which may explain the observed correlations. A sliding computation of the spectral density and correlation dimension [Grassberger P, Procaccia I (1983) Physica D 9:189-208] of mid-occipital EEG recordings derived from eight awake subjects with eyes closed was performed. The similarity between the two time courses was quantified by similarity measures and descriptive correlation coefficients. The temporal pattern of dimensional complexity showed an inverse relationship with simultaneously computed spectral power changes most pronounced in the alpha range. The group means of similarity measures and correlation coefficients were compared with the corresponding means of a sample set established by 20 Gaussian random signals. Statistically significant differences were obtained at the 0.1% level, rejecting the null hypothesis that the observed relationship is a random one. The results support the idea that the dynamics of the EEG signals investigated reflect a chaotic deterministic process with state transitions from 'high-dimensional' to 'low-dimensional' non-linear dynamics, and vice versa. Adequate neuronal models and approaches to interpret the disclosed transients and the inverse covariation between spectral density and dimensional complexity are proposed, giving additional insight into the integrative functioning of the CNS with respect to the strategy of information processing.

Activation of the Autonomic Nervous System and Blood Coagulation in Association with an Air Pollution Episode.

Air pollution has been associated with increases in hospital admissions for cardiovascular diseases. This article aims to identify subgroups of individuals who exhibit early biological responses consistent with the health effects of ambient air pollution. Resting heart rates have been recorded in a cohort of 2681 men and women aged 25-64 yr who participated in the MONICA Augsburg survey during the winter 1984/1985 and in a reexamination during the winter 1987/1988. Increases in heart rate of 1.8 beats per minute (bpm) (95% confidence interval: 0.7 to 2.8 bpm) were observed during the air pollution episode compared to nonepisode days, adjusted for potential cardiovascular risk factors and meteorological parameters. Among persons whose plasma viscosity was above the 90th percentile, heart rates increased 5.1 bpm (95% confidence interval: 2.1 to 8.2 bpm) during the air pollution episode. Persons with normal values of plasma viscosity only had an increase of 1.4 bpm (95% confidence interval: 0.3 to 2.5 bpm) during the air pollution episode. Subjects with increased plasma viscosity showed a more pronounced acceleration in heart rate at rest, pointing toward a modification of the autonomic control of the heart during an air pollution episode.

Increases in heart rate during an air pollution episode.

This paper assesses whether air pollution increases resting heart rates in 2,681 men and women aged 25-64 years who participated in the MONICA (monitoring of trends and determinants in cardiovascular disease) Augsburg cohort. Increases in heart rate were observed during the air pollution episode in January 1985 compared with non-episode days adjusted for cardiovascular risk factors and meteorologic parameters. Consistently, heart rates were also elevated at high concentrations of sulfur dioxide, total suspended particulates, or carbon monoxide. Acceleration in heart rates indicates an altered autonomic control of the heart in association with air pollution, which may contribute to the observed health effects in association with air pollution.

Cardiovascular risk factors, ECG abnormalities and quality of life in subjects with atrial fibrillation.

In Central European regions epidemiologic findings for atrial fibrillation (AF) in a randomly selected population are not available. Therefore, information obtained by a standardized examination procedure including resting 12 lead ECG of 4003 participants (2014 men, 1989 women), aged 25 to 64 years, of the MONICA-Augsburg Survey 1984/85 were analysed. Reexamination of 3753 subjects took place three years later (Follow-up Study 1987/88). Persons with AF in the baseline survey (n = 13) were compared with an age-and sex-matched control group (n = 156) without AF, chosen from the same population sample, with regard to cardiovascular risk factors, associated disease and disturbances in the subjects' general well-being. In 1984/85 thirteen cases with AF (6 males, 7 females) were observed, giving an age-standardized prevalence of AF in males of 0.22% and in females of 0.34%. The age of men with AF ranged between 50 and 63 years and of women between 61 and 64 years. No significant differences were observed in persons with AF compared to the control group in risk factor levels and alcohol consumption; however, significant differences could be seen concerning disturbances in quality of life like self-reported health status (p < 0.001), sleep disturbances (p < 0.05), antihypertensive medication (p < 0.001). AF cases were found to have further ECG abnormalities significantly more often (left anterior hemiblock: p < 0.05; ventricular premature beats: p < 0.05). In all subjects with AF in the initial examination 1984/85 AF was found three years later (chronic AF). Overall 13 new cases (7 men, 6 women) were identified in the 1987/88 follow-up. The prevalence of AF in a South German population is comparable with AF prevalences reported from studies in other populations (e.g.) Framingham 1950, Reykjavik 1967/70). Associated ECG abnormalities were found more frequently in subjects with AF. Cases with AF have considerable disturbances in their general well-being.

Association between a deletion polymorphism of the angiotensin-converting-enzyme gene and left ventricular hypertrophy.

BACKGROUND: Epidemiologic studies have shown that left ventricular hypertrophy is often found in the absence of an elevated cardiac workload. To investigate whether such hypertrophy is determined in part by genetic factors, we studied the association between this condition, as assessed by electrocardiographic criteria, and a deletion (D)-insertion (I) polymorphism of the angiotensin-converting-enzyme (ACE) gene. METHODS: A population-based random sample of 711 women and 717 men 45 to 59 years of age was studied cross-sectionally in Augsburg, Germany. Electrocardiographic indexes, including the Sokolow-Lyon index, Minnesota Code 3.1, and the Rautaharju equations, were used to detect left ventricular hypertrophy. The status of the ACE gene with respect to the deletion-insertion allele was determined by the polymerase chain reaction in all subjects with left ventricular hypertrophy and an identical number of control subjects without the condition who were matched for age, sex, and blood-pressure status. RESULTS: We identified 141 women and 149 men with evidence of left ventricular hypertrophy. Among these subjects, an excess were homozygous for the D allele of the ACE gene (odds ratio, 1.76; 95 percent confidence interval, 1.22 to 2.53; P = 0.003). The association of the DD genotype with left ventricular hypertrophy was stronger in men (odds ratio, 2.63; 95 percent confidence interval, 1.50 to 4.64; P < 0.001) than in women and was most prominent when blood-pressure measurements were normal (odds ratio, 4.05; 95 percent confidence interval, 1.76 to 9.28; P = 0.001). This association was evident for each of the scores recorded in the electrocardiographic testing for left ventricular hypertrophy. CONCLUSIONS: The findings suggest that left ventricular hypertrophy is partially determined by genetic disposition. They identify the DD genotype of ACE as a potential genetic marker associated with an elevated risk of left ventricular hypertrophy in middle-aged men.

Treatment of hypertension. Patterns of drug utilization in a metropolitan population.

In the Munich Blood Pressure Study (MBS), a cross-sectional study (MBS I) with follow-up (MBS II) of a random sample of 3,198 citizens aged 30-69 (response rate, 69.3%), treatment and control of hypertension were examined. Of the actual hypertensives 59% (221) in MBS II (373) were on drug treatment and about two-thirds (150) of those being treated had controlled blood pressure (BP). Women's BP was better controlled than men's. Of the 221 treated hypertensives 85% (188) received types of drugs or drug combinations which were in accordance with the recommendations of the German Hypertension League. However, this did not apply to the prescribed dosages of the various drugs. Of the treated hypertensives 52% were either on a diuretic, on a beta-blocker, or on a combination of both drugs. Rauwolfia alkaloids combined with a diuretic were given to 27%. In 79% of the participants who had received a beta-blocker either alone or in combination with other antihypertensive agents and who still had high BP values, the prescribed beta-blocker dosage was below the recommended daily dose. Fatigue was the most frequently reported symptom, possibly attributable to antihypertensive drug treatment. Electrocardiographic signs of left ventricular hypertrophy were found less frequently in controlled hypertensives, in comparison to treated but uncontrolled hypertensives or untreated hypertensives.