Paracrine regulation of VEGF receptors -1 and -2 on human endothelial cells: influence of primary granulosa cells

VEGF ist einer der Hauptfaktoren der physiologischen und pathophysiologischen Angiogenese. VEGF bindet an die Rezeptoren VEGFR-1 (Flt-1), die lösliche Variante sVEGFR-1 (sFlt-1) und VEGFR-2 (KDR), welche nahezu ausschließlich auf Endothelzellen exprimiert werden. Die Verfügbarkeit von VEGF kann unter anderem durch Expression des sVEGFR-1 moduliert werden. Das weibliche Reproduktionssystem ist eines der wenigen Systeme im adulten Organismus, in dem eine physiologische Angiogenese stattfindet. In der vorliegenden Arbeit wurden Endothelzellen mit Granulosazellen aus dem Corpus luteum (Gelbkörper) unter verschiedenen Kokultivierungsbedingungen analysiert. Es wurde die Regulation der VEGF-Rezeptoren auf RNA- sowie auf Proteinebene untersucht. Die Granulosazellen inhibieren die Expression des löslichen VEGFR-1s durch Sekretion eines löslichen Faktors und modulieren so möglicherweise die Verfügbarkeit des VEGFs.VEGF is a keyplayer in physiological and pathophysiological angiogenesis. VEGF and its receptors VEGFR-1 (Flt-1) and VEGFR-2 (KDR) are a tightly regulated system. Also the naturally occurring soluble form of VEGFR-1 (sVEGFR-1 or sFlt-1) - consisting of only 6 Ig-like domains - can modulate the bioavailability of VEGF by sequestering the ligand. The female reproductive tract is one of the few organs with active angiogenesis in the adult. Especially the corpus luteum and its rapid vascularization is necessary to ensure fertility. In this work a coculture system with endothelial and granulosa cells was established to study the VEGF receptor expression on endothelial cells. Granulosa cells reduce the expression of the soluble VEGFR-1 by secretion of an unknown factor.This may regulate the bioavailability of VEGF in a cell culture system

Prevalence of breastfeeding in brazil according to socioeconomic and demographics conditions

OBJETIVO: quantificar a frequência do Aleitamento Materno (AM) no Brasil, macro-regiões e áreas urbanas e rurais, segundo variáveis socioeconômicas e demográficas. METODO: amostra de 2958 crianças, de zero a um ano de idade, representativas da população brasileira. Os dados são da Pesquisa de Orçamentos Familiares-POF, 2002-2003. Utilizaram-se para análise, com tabelas de contingência, os testes qui-quadrado e de tendência para verificar as relações entre as variáveis com significância de 5%. RESULTADOS: no grupo de crianças com até 180 dias de idade, a frequência da amamentação foi de 58%. Nas regiões, foram 63%, 59%, 51%, 61% e 56%, respectivamente para Norte, Nordeste, Sudeste, Sul e Centro-oeste. Na área rural foi de 60% e na urbana 58%. Mães com maior renda e maior escolaridade apresentaram 60% e 65%, respectivamente. No grupo com mais de 180 dias a frequência no Brasil foi de 35%. Nas regiões foram: 44%, 34%, 37%, 34%, 28%, respectivamente para Norte, Nordeste, Sudeste, Sul e Centro-oeste. Na área rural foi de 39% e na urbana de 34%. Mães com menor renda e menor escolaridade apresentaram 38% e 40%, respectivamente. CONCLUSÃO: as maiores prevalências foram verificadas nas regiões Norte e Nordeste do País. Os padrões de AM diferiram quanto à faixa etária. No grupo de crianças com até 180 dias, mães com maior renda e escolaridade apresentaram maior frequência da amamentação. Por outro lado, no grupo com mais de 180 dias, a prevalência foi maior entre mães de menor renda e escolaridade.OBJECTIVE: this study aimed to quantify the prevalence of breastfeeding in Brazil, macroregions, urban and rural areas, according to socioeconomic and demographic conditions. METHODS: the sample consisted of 2,958 Brazilian children from 0 to 1 year old. Data are from the Search Family Budgets, 2002-2003. Contingency tables, the chi-square test and trend test were used in order to verify the relationship between variables, significance was set at 5% and prevalence curves of breastfeeeding were made. RESULTS: the medians of brestfeeding (BF) duration were 8 months for the North region, 9 months for Northeast, Southeast, and South and 10 months for Midwest. In the group 0 to 6 months, the frequency of BF in Brazil was 58%. We found 63%, 59%, 51%, 61% and 56%, respectively, for North, Northeast, Southeast, South and the Midwest. In the rural area we found 60% and 58% in urban area. Mothers with higher incomes and more education had 60% and 65%, respectively. In the group 7 to 12 months the prevalence in Brazil was 35%. We found: 44%, 34%, 37%, 34%, 28%, respectively, for North, Northeast, Southeast, South and the Midwest. In the rural area we reported 39% and 34% for urban area. Mothers with lower incomes and less education had 38% and 40% of BF frequency, respectively. CONCLUSION: the greatest prevalence was found in North and Northeast region and the greatest median of BF was found in Midwest region. The BF patterns differed in two age groups. In the group 0-6 months, mothers with higher income and more education had higher frequency of BF. However, in the group of children from 7 to 12 months, the prevalence of BF was higher among mothers with lower income and less education

Findings on the October Effect

Very Low Frequency (VLF) radio signals provide a unique possibility of continuously monitoring the lower ionosphere and their dynamics since these signals are reflected at the ionospheric D region between 60-90 km. Recent investigations have shown a very sharp decrease in signal amplitude at the beginning of October which deviates from the actual symmetric course of solar zenith angle variation over the year. The effect is developed differently depending on latitude, longitude and frequency, as we will present. In investigation for the cause of this phenomenon, first comparisons suggest a close correlation with the sudden reversal from easterly to westerly zonal flow, the asymmetric peak in semidiurnal solar tide S2, and the progression of the lower mesospheric temperature. Independent of the solar zenith angle mostly in high latitudes, a strong warming of the lower mesosphere during fall can be observed, confirming dominating atmospheric inner dynamics. Further studies are ongoing

The VLF network GIFDS for a ground-based monitoring of solar disturbances

It has been observed that solar flares reflect in the amplitude and phase of radio measurements. As these bursts of X-ray radiation may be harmful, the German Aerospace Center (DLR) operates the Global Ionospheric Flare Detection System (GIFDS) to continuously monitor from the ground the current state of the ionosphere's D region, which is the linking layer affected from the outside in the relevant solar spectral range and in turn taking effect on steadily available VLF signals. A major issue in flare recognition based on the radio signal changes is the non-constant progression of the quiet level over the day. That's why a flare may yield different pictures depending on the time it hits the ionosphere. Taking care of the diurnal variation is crucial for setting up a system capable of raising alerts. In addition, investigating seasonal changes is important also for understanding Earth-originating anomalies like the "October effect", a sharp decrease in signal strength during fall in mid-latitude regions (subject to the project "Analysis of the MEsosphere and Lower Ionosphere fall Effect", AMELIE). Proper flare detection and size estimation rely on identifying the normal amplitude level. As the measurements could suffer also from small-scale oscillations, the instruments were improved and harmonized to suppress noise, resulting in the compact GIFDS receiver

The Impact of Sudden Stratospheric Warmings and Elevated Stratopause Events on the VLF signal in high latitudes

Sudden Stratospheric Warmings (SSW) and Elevated Stratopause (ES) events are atmospheric wave driven winter phenomena, which lead to significant changes in wind, temperatures and vertical mass transport, especially in stratospheric and mesospheric altitudes. Likely, SSW and ES induced changes also cause modifications in the sensitive D-region ionization (~60-90 km). This bottom side of the Ionosphere behaves together with the Earth-surface as a reflection boundary for the Very Low Frequency Transmission, used for long distance communication. Here we want to study the impact of SSW/ES events on the VLF signal in high latitudes. For the identification of SSW/ES induced perturbations of the VLF signal, the typical seasonal variation and outlier caused by noise, technical adjustments or solar events need to be removed. A quiet time curve, representing the seasonal VLF signal variation under undisturbed conditions, was developed with a polynomial fit of the composite. In preparation for the composite, the VLF data needed to be leveled due to artificial amplitude steps with technical origin in the timeseries. The leveling was done with help of the Pruned Exact Linear Time method. Additionally, outlier have been removed using the Median Absolute Deviation, a method from robust statistics. With help of the developed quiet time curve, VLF signal perturbations could be identified, caused by the SSW and ES events. Here we want to describe and discuss those VLF signal perturbations for multiple links in high latitudes, considering the different pathways between Transmitter and Receiver as the ES events vary strongly with longitude

Prevalência de hipertensão arterial em militares jovens e fatores associados

OBJECTIVE: To estimate the prevalence of arterial hypertension among young military personnel and associated factors. METHODS: Cross-sectional study carried out with a sample of 380 male military personnel aged 19 to 35 years of a Brazilian Air Force unit in the city of São Paulo, Southeastern Brazil, in 2000 and 2001. The cut-off points for hypertension were: >; 140mmHg for systolic pressure and >; 90mmHg for diastolic pressure. The studied variables included risk and protective factors for hypertension, such as behavioral and nutritional characteristics. For association analysis, generalized linear model multiple regression was used, with binomial family and logarithmic link, and prevalence ratios were obtained with 90% confidence interval and hierarchical selection of variables. RESULTS: Prevalence of hypertension was 22% (90% CI: 21;29). In the final multiple regression model, it was found that the prevalence of hypertension was 68% higher among ex-smokers when compared to non-smokers (90% CI: 1.13; 2.50). Among subjects with overweight (body mass index - BMI of 25 to 29kg/m2) and obesity (BMI>; 29kg/m2) the prevalences were, respectively, 75% (90% CI: 1.23;2.50) and 178% (90% CI: 1.82;4.25) higher than among subjects with normal weight. Among those that practiced physical activity regularly, compared to those who did not practice it, the prevalence was 52% lower (90% CI: 0.30;0.90). CONCLUSIONS: Being an ex-smoker and overweight or obese were risk situations for hypertension, while the regular practice of physical activity was a protective factor in young military personnel.OBJETIVO: Estimar la prevalencia de hipertensión arterial entre militares jóvenes y factores asociados. MÉTODOS: Estudio transversal realizado con muestra de 380 militares del sexo masculino de 19 y 35 años de edad en una unidad de la Fuerza Aérea Brasilera en la cuidad de São Paulo, Sudeste de Brasil, entre 2000 y 2001. Los puntos de corte para hipertensión fueron: >; 140mmHg para presión sistólica y >; 90mmHg para presión diastólica. Las variables estudiadas incluyeron factores de riesgo y de protección para hipertensión, como características de comportamiento y nutricionales. Para análisis de las asociaciones, se utilizó regresión linear generalizada múltiple, con familia binomial y ligación logarítmica, obteniéndose tasas de prevalencia con intervalo de 90% de confianza y selección jerarquizada de las variables. RESULTADOS: La prevalencia de hipertensión arterial fue de 22% (IC 90%: 21;29). En el modelo final de la regresión múltiple se verificó prevalencia de hipertensión 68% mayor entre los exfumadores con relación a los no fumadores (IC 90%: 1,13;2,50). Entre los individuos con sobrepeso (índice de masa corporal - IMC de 25 a 29 Kg/m2) y con obesidad (IMC>;29kg/m2) las prevalencias fueron, respectivamente, 75% (IC 90%: 1,23;2,50) y 178% (IC 90%: 1,82;4,25) mayores que entre los eutróficos. Entre los que practicaban actividad física regular, comparado a los que no practicaban, la prevalencia fue 52% menor (IC 90%: 0,30;0,90). CONCLUSIONES: Ser exfumador y tener sobrepeso u obesidad fueron situaciones de riesgo para hipertensión, mientras que la práctica regular de actividad física fue factor de protección en militares jóvenes.OBJETIVO: Estimar a prevalência de hipertensão arterial entre militares jovens e fatores associados. MÉTODOS: Estudo transversal realizado com amostra de 380 militares do sexo masculino de 19 e 35 anos de idade em uma unidade da Força Aérea Brasileira em São Paulo, SP, entre 2000 e 2001. Os pontos de corte para hipertensão foram: >;140mmHg para pressão sistólica e >; 90mmHg para pressão diastólica. As variáveis estudadas incluíram fatores de risco e de proteção para hipertensão, como características comportamentais e nutricionais. Para análise das associações, utilizou-se regressão linear generalizada múltipla, com família binomial e ligação logarítmica, obtendo-se razões de prevalências com intervalo de 90% de confiança e seleção hierarquizada das variáveis. RESULTADOS: A prevalência de hipertensão arterial foi de 22% (IC 90%: 21;29). No modelo final da regressão múltipla verificou-se prevalência de hipertensão 68% maior entre os ex-fumantes em relação aos não fumantes (IC 90%: 1,13;2,50). Entre os indivíduos com sobrepeso (índice de massa corporal - IMC de 25 a 29kg/m2) e com obesidade (IMC>;29kg/m2) as prevalências foram, respectivamente, 75% (IC 90%: 1,23;2,50) e 178% (IC 90%: 1,82;4,25) maiores do que entre os eutróficos. Entre os que praticavam atividade física regular, comparado aos que não praticavam, a prevalência foi 52% menor (IC 90%: 0,30;0,90). CONCLUSÕES: Ser ex-fumante e ter sobrepeso ou obesidade foram situações de risco para hipertensão, enquanto que a prática regular de atividade física foi fator de proteção em militares jovens

A new plasmapause model based on IMAGE RPI and Van-Allen-Probe data via automatic detection

The plasmapause, i.e. the outer boundary of the plasmasphere, is characterised by a sharp electron density gradient. The Neustrelitz ESOC PlasmaPause Model (NEPPM) is a newly developed model of the plasmapause location Lpp. The actual plasmapause positions are derived from the electron density measurements recorded onboard the IMAGE satellite between 2000 and 2005 and the Van Allen probes between 2012 and 2018. An automatic algorithm is developed for detecting plasmapause location along electron density versus altitude profile. The NEPPM model functions are fitted to the Lpp measurements in a least squares sense and model parameters are determined. In our NEPPM approach an ellipse is assumed to describe the principal plasmapause shape in the geomagnetic equatorial plane. This is aligned with the bulge that follows the level of solar activity. Embedded into a 3D approach, the NEPPM allows non-dipole B vectors, providing 3D positions on the plasmapause torus for given latitude, longitude, epoch and Dst. The underlying fitting procedures recreate the varying Lpp as a function of the Dst index and magnetic local time, which gives a better conformity than the GCPM (Global Core Plasma Model). We thank ESOC (ESA/ESOC/OPS-GN) for their support in developing the model

A Crossover Trial Using High‐Fidelity Cardiovascular Phenotyping

Background Sympathetic and parasympathetic influences on heart rate (HR), which are governed by baroreflex mechanisms, are integrated at the cardiac sinus node through hyperpolarization‐activated cyclic nucleotide–gated channels (HCN4). We hypothesized that HCN4 blockade with ivabradine selectively attenuates HR and baroreflex HR regulation, leaving baroreflex control of muscle sympathetic nerve activity intact. Methods and Results We treated 21 healthy men with 2×7.5 mg ivabradine or placebo in a randomized crossover fashion. We recorded electrocardiogram, blood pressure, and muscle sympathetic nerve activity at rest and during pharmacological baroreflex testing. Ivabradine reduced normalized HR from 65.9±8.1 to 58.4±6.2 beats per minute (P<0.001) with unaffected blood pressure and muscle sympathetic nerve activity. On ivabradine, cardiac and sympathetic baroreflex gains and blood pressure responses to vasoactive drugs were unchanged. Ivabradine aggravated bradycardia during baroreflex loading. Conclusions HCN4 blockade with ivabradine reduced HR, leaving physiological regulation of HR and muscle sympathetic nerve activity as well as baroreflex blood pressure buffering intact. Ivabradine could aggravate bradycardia during parasympathetic activation