bluuebunny/crossref_metadata_2025_split huggingface dataset:
Low birth weight and longitudinal trends of cardiovascular risk factor variables from childhood to adolescence: the bogalusa heart study
Authors: Frontini Maria G , Srinivasan Sathanur R , Xu Jihua , Berenson Gerald S 
Published: November 2004

Abstract
Background
Several studies have linked low birth weight to adverse levels of cardiovascular risk factors and related diseases. However, information is sparse at a community level in the U.S. general population regarding the effects of low birth weight on the longitudinal trends in cardiovascular risk factor variables measured concurrently from childhood to adolescence.

Methods
Longitudinal analysis was performed retrospectively on data collected from the Bogalusa Heart Study cohort (n = 1141; 57% white, 43% black) followed from childhood to adolescence by repeated surveys between 1973 and 1996. Subjects were categorized into low birth weight (below the race-specific 10th percentile; n = 123) and control (between race-specific 50–75th percentile; n = 296) groups.

Results
Low birth weight group vs control group had lower mean HDL cholesterol (p = 0.05) and higher LDL cholesterol (p = 0.05) during childhood (ages 4–11 years); higher glucose (p = 0.02) during adolescence. Yearly rates of change from childhood to adolescence in systolic blood pressure (p = 0.02), LDL cholesterol (p = 0.05), and glucose (p = 0.07) were faster, and body mass index (p = 0.03) slower among the low birth weight group. In a multivariate analysis, low birth weight was related independently and adversely to longitudinal trends in systolic blood pressure (p = 0.004), triglycerides (p = 0.03), and glucose (p = 0.07), regardless of race or gender. These adverse associations became amplified with age.

Conclusions
Low birth weight is characterized by adverse developmental trends in metabolic and hemodynamic variables during childhood and adolescence; and thus, it may be an early risk factor in this regard.
Dual practice in the health sector: review of the evidence
Authors: Ferrinho Paulo , Van Lerberghe Wim , Fronteira Inês , Hipólito Fátima , Biscaia André 
Published: November 2004

AbstractThis paper reports on income generation practices among civil servants in the health sector, with a particular emphasis on dual practice. It first approaches the subject of public–private overlap. Thereafter it focuses on coping strategies in general and then on dual practice in particular.To compensate for unrealistically low salaries, health workers rely on individual coping strategies. Many clinicians combine salaried, public-sector clinical work with a fee-for-service private clientele. This dual practice is often a means by which health workers try to meet their survival needs, reflecting the inability of health ministries to ensure adequate salaries and working conditions.Dual practice may be considered present in most countries, if not all. Nevertheless, there is surprisingly little hard evidence about the extent to which health workers resort to dual practice, about the balance of economic and other motives for doing so, or about the consequences for the proper use of the scarce public resources dedicated to health.In this paper dual practice is approached from six different perspectives: (1) conceptual, regarding what is meant by dual practice; (2) descriptive, trying to develop a typology of dual practices; (3) quantitative, trying to determine its prevalence; (4) impact on personal income, the health care system and health status; (5) qualitative, looking at the reasons why practitioners so frequently remain in public practice while also working in the private sector and at contextual, personal life, institutional and professional factors that make it easier or more difficult to have dual practices; and (6) possible interventions to deal with dual practice.
The impact of antidepressant treatment on population health: synthesis of data from two national data sources in Canada
Authors: Patten Scott B 
Published: November 2004

Abstract
Background
In randomized, controlled trials, antidepressant medications have been shown to reduce the duration of major depressive episodes and to reduce the frequency of relapse during long-term treatment. The epidemiological impact of antidepressant use on episode duration and relapse frequency, however, has not been described.

Methods
Data from two Canadian general health surveys were used in this analysis: the National Population Health Survey (NPHS) and the Canadian Community Health Survey (CCHS). The NPHS is a longitudinal study that collected data between 1994 and 2000. These longitudinal data allowed an approximation of episode incidence to be calculated. The cross-sectional CCHS allowed estimation of episode duration. The surveys used the same sampling frame and both incorporated a Short Form version of the Composite International Diagnostic Interview.

Results
Episodes occurring in antidepressant users lasted longer than those in non-users. The apparent incidence of major depressive episodes among those taking antidepressants was higher than that among respondents not taking antidepressants. Changes in duration and incidence over the data collection interval were not observed.

Conclusions
The most probable explanation for these results is confounding by indication and/or severity: members of the general population who are taking antidepressants probably have more highly recurrent and more severe mood disorders. In part, this may have been due to the use of a brief predictive diagnostic interview, which may be prone to detection of sub-clinical cases. Whereas antidepressant use increased considerably over the data-collection period, differences in episode incidence and duration over time were not observed. This suggests that the impact of antidepressant medications on population health may have been less than expected.
Statistical design considerations for pilot studies transitioning therapies from the bench to the bedside
Authors: Carter Rickey E , Woolson Robert F 
Published: November 2004

AbstractPilot studies are often used to transition therapies developed using animal models to a clinical setting. Frequently, the focus of such trials is on estimating the safety in terms of the occurrence of certain adverse events. With relatively small sample sizes, the probability of observing even relatively common events is low; however, inference on the true underlying event rate is still necessary even when no events of interest are observed. The exact upper limit to the event rate is derived and illustrated graphically. In addition, the simple algebraic expression for the confidence bound is seen to be useful in the context of planning studies.
Acetylation of insulin receptor substrate-1 is permissive for tyrosine phosphorylation
Authors: Kaiser Christina , James Stephen R 
Published: November 2004

Abstract

Background

Insulin receptor substrate (IRS) proteins are key moderators of insulin action. Their specific regulation determines downstream protein-protein interactions and confers specificity on growth factor signalling. Regulatory mechanisms that have been identified include phosphorylation of IRS proteins on tyrosine and serine residues and ubiquitination of lysine residues. This study investigated other potential molecular mechanisms of IRS-1 regulation.

Results

Using the sos recruitment yeast two-hybrid system we found that IRS-1 and histone deacetylase 2 (HDAC2) interact in the cytoplasmic compartment of yeast cells. The interaction mapped to the C-terminus of IRS-1 and was confirmed through co-immunoprecipitation in vitro of recombinant IRS-1 and HDAC2. HDAC2 bound to IRS-1 in mammalian cells treated with phorbol ester or after prolonged treatment with insulin/IGF-1 and also in the livers of ob/ob mice but not PTP1B knockout mice. Thus, the association occurs under conditions of compromised insulin signalling. We found that IRS-1 is an acetylated protein, of which the acetylation is increased by treatment of cells with Trichostatin A (TSA), an inhibitor of HDAC activity. TSA-induced increases in acetylation of IRS-1 were concomitant with increases in tyrosine phosphorylation in response to insulin. These effects were confirmed using RNA interference against HDAC2, indicating that HDAC2 specifically prevents phosphorylation of IRS-1 by the insulin receptor.

Conclusions

Our results show that IRS-1 is an acetylated protein, a post-translational modification that has not been previously described. Acetylation of IRS-1 is permissive for tyrosine phosphorylation and facilitates insulin-stimulated signal transduction. Specific inhibition of HDAC2 may increase insulin sensitivity in otherwise insulin resistant conditions.
Conflict and HIV: A framework for risk assessment to prevent HIV in conflict-affected settings in Africa
Authors: Mock Nancy B , Duale Sambe , Brown Lisanne F , Mathys Ellen , O'Maonaigh Heather C , Abul-Husn Nina KL , Elliott Sterling 
Published: November 2004

AbstractIn sub-Saharan Africa, HIV/AIDS and violent conflict interact to shape population health and development in dramatic ways. HIV/AIDS can create conditions conducive to conflict. Conflict can affect the epidemiology of HIV/AIDS. Conflict is generally understood to accelerate HIV transmission, but this view is simplistic and disregards complex interrelationships between factors that can inhibit and accelerate the spread of HIV in conflict and post conflict settings, respectively. This paper provides a framework for understanding these factors and discusses their implications for policy formulation and program planning in conflict-affected settings.
Systemic chemotherapy induces microsatellite instability in the peripheral blood mononuclear cells of breast cancer patients
Authors: Fonseca Fernando LA , Sant Ana Aleksandra VL , Bendit Israel , Arias Vitor , Costa Luciano J , Pinhal Aparecida A , del Giglio Auro 
Published: November 2004

Abstract
Introduction
Systemic chemotherapy is an important part of treatment for breast cancer. We conducted the present study to evaluate whether systemic chemotherapy could produce microsatellite instability (MSI) in the peripheral blood mononuclear cell fraction of breast cancer patients.

Methods
We studied 119 sequential blood samples from 30 previously untreated breast cancer patients before, during and after chemotherapy. For comparison, we also evaluated 20 women who had no relevant medical history (control group).

Results
In 27 out of 30 patients we observed MSI in at least one sample, and six patients had loss of heterozygosity. We found a significant correlation between the number of MSI events per sample and chemotherapy with alkylating agents (P < 0.0001). We also observed an inverse correlation between the percentage of cells positive for hMSH2 and the number of MSI events per sample (P = 0.00019) and use of alkylating agents (P = 0.019).

Conclusion
We conclude that systemic chemotherapy may induce MSI and loss of heterozygosity in peripheral blood mononuclear cells from breast cancer patients receiving alkylating agents, possibly mediated by a chemotherapy-induced decrease in the expression of hMSH2. These effects may be related to the generation of secondary leukaemia in some patients, and may also intensify the genetic instability of tumours and increase resistance to treatment.
Seasonal, interannual and short‐term variability of planetary waves in Met Office stratospheric assimilated fields
Authors: Fedulina I. N. , Pogoreltsev A. I. , Vaughan G. 
Published: November 2004

AbstractMet Office stratospheric assimilated data have been used to study the variability of travelling planetary waves in the upper stratosphere during the last decade (1992–2001). To distinguish the various travelling and quasi‐standing waves, a new space‐time filtering method has been developed. The results of this analysis show that longer‐period planetary waves (10<T<20 days) have significant amplitudes mainly during winter in both hemispheres. Westward‐propagating waves are dominant in the northern hemisphere, but in the southern hemisphere eastward‐ and westward‐propagating waves have comparable amplitudes and sometimes eastward‐propagating waves are dominant. It is suggested that the main forcing of longer‐period travelling waves is an internal variability of the quasi‐stationary planetary waves in the tropo/stratosphere, and that the substantial activity of eastward‐propagating waves in the southern hemisphere is associated with seasonal changes of the general circulation of the middle atmosphere. In the shorter‐period part of the wavelet spectra (T<10 days), westward‐propagating waves are dominant and the observed maxima in amplitude spectra can be identified with the first symmetric normal atmospheric modes, the so‐called 5‐ and 4‐day waves. These waves, present in the stratosphere during most of the year, increase in amplitude during seasonal transitions. Analysis of the behaviour of wavelet amplitudes at different pressure levels shows that these normal‐mode waves propagate upward from the lower atmosphere and their amplitudes increase with altitude. There exists also a substantial long‐period modulation of the 5‐day wave amplitude with quasi‐period of about 30 days. Copyright © 2004 Royal Meteorological Society
Aircraft observations of cloud droplet number concentration: Implications for climate studies
Authors: Gultepe I. , Isaac G. A. 
Published: November 2004

AbstractDroplet number concentration (Nd) is a major parameter affecting cloud physical processes and cloud optical characteristics. In most climate models, Nd is usually assumed to be constant or a function of the droplet and aerosol number concentration (Na). Three types of cloud systems over Canada, namely Arctic clouds, maritime boundary‐layer clouds, and winter storms, were studied to obtain values of Nd as a function of temperature (T). The probability density function of Nd was also calculated to show the variability of this parameter. The results show that Nd reaches a maximum at about 10 °C (200 cm−3) and then decreases gradually to a minimum (∼1–3 cm−3) at about −35°C. A comparison of relationships between Nd and Na indicates that estimates of Nd from Na can have an uncertainty of about 30–50 cm−3, resulting in up to a 42% uncertainty in cloud short‐wave radiative forcing. This study concludes that the typical fixed values of Nd, which are ∼100 cm−3 and ∼200 cm−3 for maritime and continental clouds, respectively, and the present relationships of Nd to Na, could result in a large uncertainty in the heat and moisture budgets of the earth's atmosphere. It is suggested that the use of relationships between Nd and T can improve climate simulations. © Crown copyright, 2004. Royal Meteorological Society
Impact of the GEM model simplified physics on extratropical singular vectors
Authors: Zadra Ayrton , Buehner Mark , Laroche Stéphane , Mahfouf Jean‐françois 
Published: November 2004

AbstractA simplified physics package, containing parametrizations of vertical diffusion, subgrid‐scale orographic drag, stratiform precipitation and convective precipitation, was built for the four‐dimensional variational data assimilation system that is being developed for the Canadian Global Environmental Multiscale model. To validate this package and measure its impact on the behaviour of unstable disturbances, a series of singular vector experiments was conducted. In a control experiment with vertical diffusion only, a set of 45 extratropical singular vectors was generated for a northern hemisphere winter case, using the total energy norm and an optimization time interval of 48 hours. Subsequently, the remaining components of the simplified physics were activated one by one and their influence was measured by changes in the energy partition, energy growth and spatial distribution of singular vectors. Cross‐propagation tests were also made, where singular vectors from one experiment were evolved with the tangent‐linear model of another. Results show that the orographic drag reduces the growth of singular vectors while the moist physics enhance the growth and shifts the energy of singular vectors toward smaller scales. Integrations of the nonlinear model with full physics indicate that, for amplitudes typical of analysis increments, the evolution of extratropical singular vectors is well described by the linearized model although growth rates are reduced by nonlinearities. © Crown copyright, 2004. Royal Meteorological Society
Bora‐driven potential vorticity banners over the Adriatic
Authors: Grubišíc Vanda 
Published: November 2004

AbstractA case study is presented of the secondary potential vorticity (PV) banners over the northern Adriatic that occurred in an early stage of a bora on 7 November 1999 during the Mesoscale Alpine Programme (MAP) Special Observation Period. The dynamics and structure of the lee‐side and cross‐mountain flow past the Dinaric Alps were investigated using data collected in a dual‐aircraft (NCAR Electra and NOAA P‐3)MAP Intensive Observing Period 15 mission over the Adriatic and high‐resolution numerical simulations. The observational study employs flight‐level, dropsonde, and Scanning Aerosol Backscatter Lidar data. The observed flow structure is compared with simulations results of the COAMPS model run at a horizontal resolution of 3 km.The Dinaric Alps, the north‐west/south‐east oriented coastal mountain range of Croatia, has an irregular ridge line with a number of peaks in the range of 1.5–2 km with several prominent mountain passes. The identified jet and wake structure within the east‐north‐easterly bora over the Adriatic was found to be well correlated with the upwind distribution of mountain passes and peaks. The wake flow structure was found also to be in excellent agreement with the climatological profile of the bora strength along the Croatian coast. The attendant secondary PV banners separating individual jets and wakes, diagnosed by computing PV from the flight‐level data, were found to have a characteristic horizontal scale of 10–25 km, and a maximum amplitude of up to ∼6 pvu within the boundary layer. Over the open sea, the thickness of the boundary layer, within which the east‐north‐easterly bora also achieved its maximum strength, was approximately 1 km.Detailed comparison with the numerical model results shows that, at the horizontal resolution of 3 km, the COAMPS model reproduces well the overall flow structure. The COAMPS‐simulated PV field was found to be in good agreement with the PV derived from observations. The differences in substructure between simulated and experimentally derived PV profiles derive from minor differences between modelled and observed velocity and potential temperature profiles, which are subsequently accentuated by computing differentiated quantities such as vorticity and potential temperature gradients. The high predictability and steadiness of the PV banners, and a good correlation with the geometry of the upwind topography, support the orographic generation mechanism of PV with dissipation in hydraulic jumps and gravity‐wave breaking regions as the likely main source of PV. Copyright © 2004 Royal Meteorological Society
Empirical evaluation of an extended similarity theory for the stably stratified atmospheric surface layer
Authors: Sodemann Harald , Foken Thomas 
Published: November 2004

AbstractThe theory of the atmospheric stable boundary layer (SBL) has recently been extended by a distinction between nocturnal and long‐lived SBLs. The latter SBL type, which includes influences from the free atmosphere on fluxes in the surface layer, requires a modification of the traditional Monin–Obukhov similarity theory. In the present study, the applicability of this extended theory for long‐lived SBLs is evaluated and the required coefficients are estimated using data from Antarctica.Changes in wind and temperature gradients due to different weather conditions are shown to exert a strong influence on the estimation of the new coefficients CuN and CθN. Using the wind gradient as classification criterion, the momentum flux coefficient CuN is estimated to range between 0.51±0.03 and 2.26±0.08. Using the temperature gradient as classification criterion, the heat flux coefficient CθN is estimated to range between 0.022±0.002 and 0.040±0.001.At present, the proposed new scaling theory is still in a preliminary stage. Possible future improvements should take into account factors influencing the wind and temperature gradients, such as weather conditions. An artificial background correlation strongly imprints upon the parameter estimation, suggesting that both the methodology for estimating the new coefficients CuN and CθN and the choice of the nondimensional variables for this extended scaling theory may require some revision. Copyright © 2004 Royal Meteorological Society
Interannual variability of stratospheric trace gases: The role of extratropical wave driving
Authors: Ma J. , Waugh D. W. , Douglass A. R. , Kawa S. R. , Newman P. A. , Pawson S. , Stolarski R. , Lin S. J. 
Published: November 2004

AbstractThe interannual variability of methane and ozone from a 35‐year middle atmosphere climate model simulation with no interannual variations in external forcing or chemistry is examined. The internal dynamics in the model produces large tracer interannual variability, particularly in polar regions. During winter and spring the interannual standard deviation in the polar lower‐middle stratosphere is about 30% of the climatological mean for methane and 15% for ozone. Global‐scale, coherent interannual variations in temperature, residual circulation, and tracers are correlated with variability in the extratropical wave forcing. Statistically significant positive correlations between wave driving and polar tracer tendencies, including column ozone, occur from autumn to spring in both hemispheres. These positive correlations imply that interannual variations in polar tracers are dominated by variations in the horizontal eddy transport and not by variations in residual mean descent rates. Copyright © 2004 Royal Meteorological Society
Angiogenic response induced by acellular aortic matrix in vivo
Authors: Conconi Maria Teresa , Nico Beatrice , Mangieri Domenica , Tommasini Mara , di Liddo Rosa , Parnigotto Pier Paolo , Nussdorfer Gastone G. , Ribatti Domenico 
Published: November 2004

AbstractIn this study, we investigated the angiogenic response induced by acellular aortic matrices implanted in vivo onto the chick embryo chorioallantoic membrane (CAM), a useful model for such investigation. Results showed that acellular matrices were able to induce a strong angiogenic response comparable to that of fibroblast growth factor 2 (FGF‐2), a well‐known angiogenic cytokine. The angiogenic response was further increased when exogenous FGF‐2 or transforming growth factor beta 1 (TGF‐β1) were added to the matrices and inhibited by the addition of an anti‐FGF‐2 or anti‐TGF‐β1 antibodies. The response may be considered dependent on a direct angiogenic effect exerted by the matrices and in part also by the presence of FGF‐2 and TGF‐β1 in the acellular matrices. © 2004 Wiley‐Liss, Inc.