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The potential impact of large numbers of Global Navigation Satellite System radio occultation (GNSS-RO) observations on numerical weather prediction is investigated using a global observing system simulation experiment (OSSE). The hybrid four-dimensional ensemble variational Gridpoint Statistical Interpolation (GSI) data assimilation system and Global Earth Observing System (GEOS) model are used to ingest up to 100 000 GNSS-RO soundings per day in addition to the current suite of conventional and radiance data. Analysis quality, forecast skill, and forecast sensitivity to observation impact are examined with differing quantities of additional GNSS-RO profiles. It is found that saturation of information from additional RO soundings has not been reached with 100 000 soundings per day. There are some indications of suboptimal performance of the GSI in handling GNSS-RO observations particularly in the middle- and lower-tropospheric extratropics. [ABSTRACT FROM AUTHOR]

Adjoint models are often used to estimate the impact of different observations on short-term forecast skill. A common difficulty with the evaluation of short-term forecast quality is the choice of verification fields. The use of self-analysis fields for verification is typical but incestuous, and it introduces uncertainty resulting from biases and errors in the analysis field. In this study, an observing system simulation experiment (OSSE) is used to explore the uncertainty in adjoint model estimations of observation impact. The availability of the true state for verification in the OSSE framework in the form of the nature run allows calculation of the observation impact without the uncertainties present in self-analysis verification. These impact estimates are compared with estimates calculated using self-analysis verification. The Global Earth Observing System, version 5 (GEOS-5), forecast model with the Gridpoint Statistical Interpolation system is used with the National Aeronautics and Space Administration Global Modeling and Assimilation Office (NASA/GMAO) OSSE capability. The adjoint model includes moist processes, with total wet energy selected as the norm for evaluation of observation impacts. The results show that there are measurable but small errors in the adjoint model estimation of observation impact as a result of self-analysis verification. In general, observations of temperature and winds tend to have overestimated impacts with self-analysis verification while observations of humidity and moisture-affected observations tend to have underestimated impacts. The small magnitude of the differences in impact estimates supports the robustness of the adjoint method of estimating observation impacts. [ABSTRACT FROM AUTHOR]

Driven by the data requirements envisioned for the fifth generation (5G) of wireless services, the mobile community is focusing on breaking the spectrum gridlock that characterizes cellular technology. In this context, researchers and industries have identified millimeter-wave (mmWave) communications as a key enabler for providing unprecedented radio access capacity. Nevertheless, due to the specific differences between this technology and microwave systems, there are multiple research challenges spanning from the hardware to the overall system architecture. The goal of this column is to provide an overview of these challenges and discuss the most promising solutions to make 5G mmWave communications a reality. [ABSTRACT FROM PUBLISHER]

General circulation models can now be run at very high spatial resolutions to capture finescale features, but saving the full-spatial-resolution output at every model time step is usually not practical because of storage limitations. To reduce storage requirements, the model output may be produced at reduced temporal and/or spatial resolutions. When this reduced-resolution output is then used in situations where spatiotemporal interpolation is required, such as the generation of synthetic observations for observing system simulation experiments, interpolation errors can significantly affect the quality and usefulness of the reduced-resolution model output. Although it is common in practice to record model output at the highest possible spatial resolution with relatively infrequent temporal output, this may not be the best option to minimize interpolation errors. In this study, two examples using a high-resolution global run of the Goddard Earth Observing System Model, version 5 (GEOS-5), are presented to illustrate cases in which the optimal output dataset configurations for interpolation have high temporal frequency but reduced spatial resolutions. Interpolation errors of tropospheric temperature, specific humidity, and wind fields are investigated. The relationship between spatial and temporal output resolutions and interpolation errors is also characterized for the example model. [ABSTRACT FROM AUTHOR]

The hippocampus has a key role in a number of neurodegenerative diseases, such as Alzheimer's Disease. Here we present a novel method for the automated segmentation of the hippocampus from structural magnetic resonance images (MRI), based on a combination of multiple classifiers. The method is validated on a cohort of 50 T1 MRI scans, comprehending healthy control, mild cognitive impairment, and Alzheimer's Disease subjects. The preliminary release of the EADC-ADNI Harmonized Protocol training labels is used as gold standard. The fully automated pipeline consists of a registration using an affine transformation, the extraction of a local bounding box, and the classification of each voxel in two classes (background and hippocampus). The classification is performed slice-by-slice along each of the three orthogonal directions of the 3D-MRI using a Random Forest (RF) classifier, followed by a fusion of the three full segmentations. Dice coefficients obtained by multiple RF (0.87 ± 0.03) are larger than those obtained by a single monolithic RF applied to the entire bounding box, and are comparable to state-of-the-art. A test on an external cohort of 50 T1 MRI scans shows that the presented method is robust and reliable. Additionally, a comparison of local changes in the morphology of the hippocampi between the three subject groups is performed. Our work showed that a multiple classification approach can be implemented for the segmentation for the measurement of volume and shape changes of the hippocampus with diagnostic purposes. [ABSTRACT FROM AUTHOR]

Most rawinsondes are launched once or twice daily, at 0000 and/or 1200 UTC; only a small number of the total rawinsonde observations are taken at 0600 and 1800 UTC ('off hour' cycle times). In this study, the variations of forecast and analysis quality between cycle times and the potential improvement of skill due to supplemental rawinsonde measurements at 0600 and 1800 UTC are tested in the framework of an observing system simulation experiment (OSSE). The National Aeronautics and Space Administration Global Modeling and Assimilation Office (NASA GMAO) Goddard Earth Observing System Model, version 5 (GEOS-5), is used with the GMAO OSSE setup for an experiment emulating the months of July and August with the 2011 observational network. The OSSE is run with and without supplemental rawinsonde observations at 0600 and 1800 UTC, and the differences in analysis error and forecast skill are quantified. The addition of supplemental rawinsonde observations results in significant improvement of analysis quality in the Northern Hemisphere for both the 0000/1200 and 0600/1800 UTC cycle times, with greater improvement for the off-hour times. Reduction of root-mean-square errors on the order of 1% -3% for wind and temperature is found at the 24- and 48-h forecast times. There is a slight improvement in Northern Hemisphere anomaly correlations at the 120-h forecast time. [ABSTRACT FROM AUTHOR]

The inclusion of linearized moist physics can increase the accuracy of 4D-Var data assimilation and adjoint-based sensitivity analysis. Moist processes such as convection can exhibit nonlinear behaviour. As a result, representation of these processes in a linear way requires much care; a straightforward linearization may yield a poor approximation to the behaviour of perturbations of interest and could contain numerical instability. Here, an extensive numerical study of the Jacobian of the relaxed Arakawa-Schubert ( RAS) convection scheme is shown. A Jacobian based on perturbations at individual model levels can be used to understand the physical behaviour of the RAS scheme, predict how sensitive that behaviour is to the prognostic variables and determine the stability of a linearization of the scheme. The linearity of the scheme is also considered by making structured perturbations, constructed from the principle components of the model variables. Based on the behaviour of the Jacobian operator and the results when using structured perturbations, a suitable method for linearizing the RAS scheme is determined. For deep, strong convection, the structures of the RAS Jacobian are reasonably simple, the rate at which finite-amplitude estimates of the structures change with respect to input perturbations is small and the eigenmodes of the Jacobian are not prohibitively unstable. For deep convection, an exact linearization is therefore suitable. For shallow convection, the RAS scheme can be more sensitive to the input prognostic variables due to the faster time-scales and proximity to switches. Linearization of the RAS therefore requires some simplifications to smooth the behaviour for shallow convection. It is noted that the physical understanding of the scheme gained from examining the Jacobian provides a useful tool to the developers of nonlinear physical parametrizations. [ABSTRACT FROM AUTHOR]

A global Observing System Simulation Experiment (OSSE) framework has been developed at the National Aeronautics and Space Administration Global Modeling and Assimilation Office (NASA/GMAO). The OSSE uses a 13-month integration of the European Centre for Medium-Range Weather Forecasts (ECMWF) operational model as the Nature Run, and the Goddard Earth Observing System version-5 (GEOS-5) forecast model with Gridpoint Statistical Interpolation (GSI) data assimilation as the forecast model. Synthetic observations have been developed with correlated observation errors to replicate the observing network from 2005-2006. The performance of the GMAO OSSE in terms of forecast skill and observation impacts is evaluated against real observational data for the same period. Metrics of anomaly correlation of 500 hPa geopotential and root-mean-square error of temperature and wind fields for 120 h forecasts are calculated for once-daily forecasts from July 2005, and an adjoint is used to measure observation impacts of different data types. The forecast skill of the OSSE is found to be slightly higher than for real data, with smaller observation impacts overall, possibly due to insufficient model error in the OSSE. While there is similar relative ranking of observation impact for most data types in the OSSE compared with real data, for individual satellite channels the agreement is not as good. Some caveats and difficulties of using the OSSE system are discussed along with recommendations of how to avoid potential pitfalls when performing OSSEs. [ABSTRACT FROM AUTHOR]

Background: Human papillomavirus (HPV) is the most common sexually transmitted infection in the United States and disproportionately affects adolescents and young adults. Although a safe and efficacious vaccine is available, many college students are unimmunized against HPV. Most students presenting to college health centers are within the age range for catch-up immunization, giving nurse practitioners (NPs) in this setting an opportunity to increase vaccination rates. More information is needed about college students' HPV knowledge, attitudes, and vaccination uptake so that NPs can make effective vaccine recommendations to this population., Purpose: To examine (a) Knowledge and attitudes about HPV and its vaccine; (b) HPV immunization practices; and (c) factors associated with HPV knowledge, attitudes, and vaccination among college students in a US university., Methods: This cross-sectional quantitative study collected data from participants in a state university student health center. Data collected included knowledge, attitudes, and practices about HPV and its vaccine from 627 students., Results: Participants had a moderately low HPV knowledge but positive attitudes toward HPV and its vaccine. Participants with a higher level of HPV knowledge were US born, health-related majors, married or divorced, and had positive attitudes. Higher HPV knowledge, vaccine uptake, and a family history of cervical cancer were associated with positive attitudes. Predictors for vaccine uptake include being a health-related major and positive vaccine attitudes., Implications for Practice: The results of this study help NPs, registered nurses, and other health care providers make effective HPV vaccine recommendations to college students. Students with positive HPV attitudes can serve as peer educators to increase HPV vaccination awareness in this population., Competing Interests: Competing interests: The authors report no conflicts of interest., (Copyright © 2020 American Association of Nurse Practitioners.)

Aim and Objectives: The aim of this article was to explore the implications of the new Euratom dose limit for occupational radiation protection in the context of medical occupational radiation exposures. The European Directive 2013/59/Euratom takes into account the new recommendations on reduction in the dose limit for the lens of the eye for planned occupational exposures released in 2012 by the International Commission on Radiological Protection (ICRP 118)., Materials and Methods: Different dose-monitoring procedures and devices were considered. Occupational eye lens doses reported by previous studies were analyzed, mainly considering workers involved in interventional procedures with X-rays. The current status of eye lens radiation protection and the main methods for dose reduction were investigated., Results: The analysis showed that the workers, potentially exceeding the new limit, are clinical staff performing interventional procedures with a relatively high X-ray dose. Regarding radiological protection issues, the considered literature reports that the proper use of personal protective equipment may reduce the eye lens absorbed dose., Conclusion: The evaluation of the occupational eye lens dose is essential to establish which method of personal dose monitoring should be preferred. Furthermore, education and training about the right use of personal protective equipment are important for medical staff working with ionizing radiation.

Aims and Objectives: The aim of this study was to properly define the information regarding patient exposure to Ionizing Radiations in the radiological report, according to the European Directive 2013/59/EURATOM (EU 2013/59 art.58(b)). For this purpose, we evaluated the results from other Member States EU 2013/59 transpositions and from Guidelines recommendation published by International Organizations involved in diagnostic radiology. A practical way for implementing art.58 is also traced., Materials and Methods: Dosimetric quantities, such as exposure, absorbed dose and effective dose which may be included in radiological report, were first analyzed; then, in order to define international state of art of Member States EU 2013/59 transposition, a Web research using French, English, Spanish and German key words was performed., Results: EU 2013/59 transposition for 5 Member States was reported. Especially regarding art.58, a European project reports that few European countries (11 of 28) have identified the dose metrics to be used in radiological report. Scientific organizations supporting clinical radiologists and medical physicists have published Guidelines reporting parameters useful to quantify the radiation output and to assess patient dose., Conclusions: Our research revealed that there is not a shared interpretation of patient exposure information to be included in radiological report. Nevertheless, according to scientific community, authors believe that the exposure is the most appropriate information that could be included in radiological report. Alternatively, but with more expensiveness, a risk index based on effective dose could be used. Moreover, the systematic exposure information recorded could be useful for dose estimates of population from medical exposure.

Identifying accurate biomarkers of cognitive decline is essential for advancing early diagnosis and prevention therapies in Alzheimer's disease. The Alzheimer's disease DREAM Challenge was designed as a computational crowdsourced project to benchmark the current state-of-the-art in predicting cognitive outcomes in Alzheimer's disease based on high dimensional, publicly available genetic and structural imaging data. This meta-analysis failed to identify a meaningful predictor developed from either data modality, suggesting that alternate approaches should be considered for prediction of cognitive performance., (Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.)

In this paper, we present an accurate and realistic simulation for body area networks (BAN) and body-to-body networks (BBN) using deterministic and semi-deterministic approaches. First, in the semi-deterministic approach, a real-time measurement campaign is performed, which is further characterized through statistical analysis. It is able to generate link-correlated and time-varying realistic traces (i.e., with consistent mobility patterns) for on-body and body-to-body shadowing and fading, including body orientations and rotations, by means of stochastic channel models. The full deterministic approach is particularly targeted to enhance IEEE 802.15.6 proposed channel models by introducing space and time variations (i.e., dynamic distances) through biomechanical modeling. In addition, it helps to accurately model the radio link by identifying the link types and corresponding path loss factors for line of sight (LOS) and non-line of sight (NLOS). This approach is particularly important for links that vary over time due to mobility. It is also important to add that the communication and protocol stack, including the physical (PHY), medium access control (MAC) and networking models, is developed for BAN and BBN, and the IEEE 802.15.6 compliance standard is provided as a benchmark for future research works of the community. Finally, the two approaches are compared in terms of the successful packet delivery ratio, packet delay and energy efficiency. The results show that the semi-deterministic approach is the best option; however, for the diversity of the mobility patterns and scenarios applicable, biomechanical modeling and the deterministic approach are better choices.

In this study we present a novel fully automated Hippocampal Unified Multi-Atlas-Networks (HUMAN) algorithm for the segmentation of the hippocampus in structural magnetic resonance imaging. In multi-atlas approaches atlas selection is of crucial importance for the accuracy of the segmentation. Here we present an optimized method based on the definition of a small peri-hippocampal region to target the atlas learning with linear and non-linear embedded manifolds. All atlases were co-registered to a data driven template resulting in a computationally efficient method that requires only one test registration. The optimal atlases identified were used to train dedicated artificial neural networks whose labels were then propagated and fused to obtain the final segmentation. To quantify data heterogeneity and protocol inherent effects, HUMAN was tested on two independent data sets provided by the Alzheimer's Disease Neuroimaging Initiative and the Open Access Series of Imaging Studies. HUMAN is accurate and achieves state-of-the-art performance (Dice[Formula: see text] and Dice[Formula: see text]). It is also a robust method that remains stable when applied to the whole hippocampus or to sub-regions (patches). HUMAN also compares favorably with a basic multi-atlas approach and a benchmark segmentation tool such as FreeSurfer.

Neurodegenerative diseases are frequently associated with structural changes in the brain. Magnetic resonance imaging (MRI) scans can show these variations and therefore can be used as a supportive feature for a number of neurodegenerative diseases. The hippocampus has been known to be a biomarker for Alzheimer disease and other neurological and psychiatric diseases. However, it requires accurate, robust, and reproducible delineation of hippocampal structures. Fully automatic methods are usually the voxel based approach; for each voxel a number of local features were calculated. In this paper, we compared four different techniques for feature selection from a set of 315 features extracted for each voxel: (i) filter method based on the Kolmogorov-Smirnov test; two wrapper methods, respectively, (ii) sequential forward selection and (iii) sequential backward elimination; and (iv) embedded method based on the Random Forest Classifier on a set of 10 T1-weighted brain MRIs and tested on an independent set of 25 subjects. The resulting segmentations were compared with manual reference labelling. By using only 23 feature for each voxel (sequential backward elimination) we obtained comparable state-of-the-art performances with respect to the standard tool FreeSurfer.

The human body is an extremely challenging environment for the operation of wireless communications systems, not least because of the complex antenna-body electromagnetic interaction effects which can occur. This is further compounded by the impact of movement and the propagation characteristics of the local environment which all have an effect upon body centric communications channels. As the successful design of body area networks (BANs) and other types of body centric system is inextricably linked to a thorough understanding of these factors, the aim of this paper is to conduct a survey of the current state of the art in relation to propagation and channel models primarily for BANs but also considering other types of body centric communications. We initially discuss some of the standardization efforts performed by the Institute of Electrical and Electronics Engineers 802.15.6 task group before focusing on the two most popular types of technologies currently being considered for BANs, namely narrowband and Ultrawideband (UWB) communications. For narrowband communications the applicability of a generic path loss model is contended, before presenting some of the scenario specific models which have proven successful. The impacts of human body shadowing and small-scale fading are also presented alongside some of the most recent research into the Doppler and time dependencies of BANs. For UWB BAN communications, we again consider the path loss as well as empirical tap delay line models developed from a number of extensive channel measurement campaigns conducted by research institutions around the world. Ongoing efforts within collaborative projects such as Committee on Science and Technology Action IC1004 are also described. Finally, recent years have also seen significant developments in other areas of body centric communications such as off-body and body-to-body communications. We highlight some of the newest relevant research in these areas as well as discussing some of the advanced topics which are currently being addressed in the field of body centric communications.

Background: Oral and poster presentations at congresses are essential to spread scientific knowledge among the medical community. Many scientific societies have analyzed the quality of papers presented at their meetings but no information on abstracts' evaluation has been presented in Public Health field., Design and Methods: This study aims to examine the quality of abstracts presented at annual meetings of Italian Public Health Society (SItI) in the period 2005-2010 through a validated checklist grid, evaluating eight dimensions: Inherency, Structure, Originality, Objectives, Study design, Sources, Results, Conclusions. Each item was scored from 0 to 3 points (max score: 24) and we used the average score in our study (15) as threshold of good quality. A multivariate analysis was performed in order to investigate predictors of score of abstracts presented., Results: A total of 4,399 abstracts (1,172 oral communications, 3,227 posters) was examined. Around 60% were submitted by Universities and around 40% were from Central Italy. The highest quality was found in the fields of Vaccines (average score 18.9), Infectious Diseases (18) and in abstracts submitted by Universities (16.4). Predictors of lower quality identified were geographical area and affiliation (p= 0.002). Abstracts containing well-written Results, Conclusions and Objectives (3 points) were more likely to be of high quality(OR=55.6, OR=41.9, and OR=157.4; p>0.001) CONCLUSIONS: This is the first European study evaluating the quality of abstracts in the public health field. A reliable evaluation tool is fundamental to offer a transparent methodology of assessment and to improve the quality of research.

A wireless 64-channel ElectroCorticoGram (ECoG) recording implant named WIMAGINE(®) has been designed for clinical applications. This active implantable medical device is able to record ECoG on 64 electrodes with selectable gain and sampling frequency, with less than 0.7 µVRMS input referred noise in the [0.5 Hz - 300 Hz] band. It is powered remotely through an inductive link at 13.56 MHz, communicates wirelessly on the MICS band at 402-405 MHz with a custom designed base station connected to a PC and complies with the regulations applicable to class III AIMD. The design of the housing and the antenna have been optimized to ease the surgery and to take into account all the requirements of a clinical trial in particular patient safety and comfort. The main features of this WIMAGINE(®) implantable device and its architecture will be presented, as well as its performances and in vivo validations.

A wireless, low power, 64-channel data acquisition system named WIMAGINE has been designed for ElectroCorticoGram (ECoG) recording. This system is based on a custom integrated circuit (ASIC) for amplification and digitization on 64 channels. It allows the RF transmission (in the MICS band) of 32 ECoG recording channels (among 64 channels available) sampled at 1 kHz per channel with a 12-bit resolution. The device is powered wirelessly through an inductive link at 13.56 MHz able to provide 100mW (30mA at 3.3V). This integration is a first step towards an implantable device for brain activity monitoring and Brain-Computer Interface (BCI) applications. The main features of the WIMAGINE platform and its architecture will be presented, as well as its performances and in vivo studies.

Objectives: We sought to characterize the acoustical behavior of the experimental ultrasound contrast agent BR14 by determining the acoustic pressure threshold above which nonlinear oscillation becomes significant and investigating microbubble destruction mechanisms., Materials and Methods: We used a custom-designed in vitro setup to conduct broadband attenuation measurements at 3.5 MHz varying acoustic pressure (range, 50-190 kPa). We also performed granulometric analyses on contrast agent solutions to accurately measure microbubble size distribution and to evaluate insonification effects., Results: Attenuation did not depend on acoustic pressure less than 100 kPa, indicating this pressure as the threshold for the appearance of microbubble nonlinear behavior. At the lowest excitation amplitude, attenuation increased during insonification, while, at higher excitation levels, the attenuation decreased over time, indicating microbubble destruction. The destruction rate changed with pressure amplitude suggesting different destruction mechanisms, as it was confirmed by granulometric analysis., Conclusions: Microbubbles showed a linear behavior until 100 kPa, whereas beyond this value significant nonlinearities occurred. Observed destruction phenomena seem to be mainly due to gas diffusion and bubble fragmentation mechanisms.

Background: Patients with atherosclerotic renovascular disease (ARVD) are almost invariably treated by revascularization. However, the long-term outcomes of this approach on survival and progression to renal failure have not been investigated and have not been compared with that of a purely medical treatment. The aim of this observational study was to investigate factors affecting long-term (over 5 years) outcome, survival and renal function of patients with ARVD treated invasively or medically., Methods: ARVD was demonstrated angiographically in 195 patients who were consecutively enrolled into a follow-up study. Patient age was 65.6+/-11.2 years, serum creatinine was 1.74+/-1.22 mg/dl and renal artery lumen narrowing was 73.5+/-17.5%. A revascularization was performed in 136 patients, whereas 54 subjects having comparable characteristics were maintained on a medical treatment throughout the study; five patients were lost during follow-up., Results: The main follow-up was 54.4+/-40.4 months. The assessment of cardiovascular survival and renal survival at the end of follow-up revealed 46 cardiovascular deaths, 20 patients with end-stage renal disease (ESRD) and 41 patients with an increase in serum creatinine of over one-third. The multivariate analysis showed that renal revascularization did not affect mortality or renal survival compared with medical treatment. Revascularization produced slightly lower increases in serum creatinine and a better control of blood pressure. A longer survival was associated with the use of angiotensin-converting enzyme inhibitors (ACEIs) (P = 0.002) in both revascularized and medically treated patients. The only significant predictor of ESRD was an abnormal baseline serum creatinine., Conclusions: On long-term follow-up, ARVD was associated with a poor prognosis due to a high cardiovascular mortality and a high rate of ESRD. In our non-randomized study, revascularization was not a major advantage over medical treatment in terms of mortality or renal survival. The use of ACEIs was associated with improved survival.

Background: Atherosclerosis is a major problem in end-stage renal disease (ESRD) patients treated by hemodialysis and the prevalence of carotid artery disease is much higher in this group than in the general population. Repeated exposure to cytokine-inducing material, derived from dialysate, may induce a chronic inflammatory state, that could contribute to the atherosclerotic process. Endotoxin is mainly cleared from plasma by the sCD14, the soluble form of the endotoxin receptor CD14. The levels of sCD14 are associated with a polymorphism, -159 C/T, of the CD14 gene., Methods and Results: We determined the genotype for the -159 C/T polymorphism in 158 haemodialysis patients and 168 healthy controls. In patients we investigated the association between the CD14 polymorphism and carotid artery disease. With a prospective follow-up study we assessed whether the CD14 polymorphism shows any relationship with cardiovascular mortality. The polymorphic frequency was comparable between patients and controls. In patients, we found a significant difference in the prevalence of carotid artery disease between groups divided by genotype: CC 87.0%, CT 71.7%, TT 48.9% (p = 0.0093). In dialysis patients with hypertension the CC polymorphism was associated with an increased cardiovascular mortality., Conclusions: These results demonstrate an association between the -159 C/T polymorphism of the CD14 gene and carotid artery disease in dialysis patients. We hypothesize that the low plasma clearance of endotoxin associated with the CC genotype facilitates the atherogenic action of endotoxin-derived cytokines in haemodialysis patients.

Background: The aim of the present study was to evaluate the systemic inflammatory response to CPB in paediatric patients undergoing surgical correction of congenital heart diseases., Experimental Design: comparative investigation., Setting: paediatric cardiology hospital, Intervention: ICAM-1, IL-8, and IL-6 production were analysed before and during CPB, and after surgery in 9 paediatric patients, submitted to cardiocirculatory arrest (Group A); and in 11 without cardiocirculatory arrest (Group B)., Measures: ICAM-1, IL-8, and IL-6 production were analysed from arterial samples before and during CPB, and after surgery., Results: In group A vs group B a significant increase of IL-8 was detected during (297+/-250 vs 11+/-19 pg x ml(-1), p<0.001) and after (100+/-230 vs n.d. pg x ml(-1)) surgery and was correlated with the duration of operation (r=0.759; p=0.0001) and clamping time (r=0.738; p<0.05). After surgery in group A, IL-6 levels (35+/-43 pg x ml) were higher than those in group B (2+/-5 pg x ml), and a good correlation was observed between IL-6 and duration of aortic clamping (r=0.714; p=0.048), cardiac arrest, (r=0.714; p=0.048), and length of surgery (r=0.867; p=0.04)., Conclusions: In children who underwent CPB with cardiocirculatory arrest cytokine production seems related to duration of operation and amplified by ischemia-reperfusion phenomena.

Aim: Renovascular hypertension (RVH) is associated with a high prevalence of target organ damage and a high mortality. We have undertaken this follow-up study to assess the role played by comorbid conditions, and pharmacological treatment on survival, and on renal function in 64 patients with diffuse atherosclerotic vascular and renovascular disease (RVD)., Patients and Methods: The patients were followed for an average period of 37.3+/-20.4 months., Results: At the end of the follow-up we found a cumulative survival at 5 years of 60%+/-10. Cerebrovascular and cardiovascular disease were responsible for 92% of deaths. A decrease in creatinine clearance >10 ml/min at 5 years was found in 65% of patients, 3 of whom ended in dialysis. Multivariate analysis of predictors of survival showed that treatment with angiotensin converting enzyme inhibitors (ACEi) was significantly associated with a favourable outcome (p = 0.019). Conversely, proteinuria had a negative effect. Renal survival was best predicted by the level of renal function at entry (p = 0.02), and was not influenced by pharmacological treatment., Conclusion: We conclude that ACEi exerts a beneficial effect on survival without affecting renal function in patients with RVD due to unilateral renal stenosis.

We examined the effects of hypoxic/ischemic stress on cerebral arteriolar responses to oxytocin in anesthetized piglets. Pial arteriolar diameters were measured using a cranial window and intravital microscopy. First, we evaluated arteriolar responses to topical application of oxytocin during normoxic conditions. We then determined whether 5-10 min of arterial hypoxia, ischemia, or asphyxia alters oxytocin-induced responses. Arterial hypoxia was produced by inhalation of 7.5% O2-92.5% N2 for 10 min. Ischemia was achieved by increasing intracranial pressure for 10 min. Asphyxia was achieved by turning off the ventilator for 5 min. During normoxic conditions, oxytocin dilated pial arterioles by 9 +/- 1% at 10(-8) and by 16 +/- 1% at 10(-6) mol/l (n = 47, p < 0.05). Arteriolar responses to oxytocin did not change with repeated applications (n = 10). Following hypoxia, dilator effect of oxytocin was not changed at 10(-8) (8 +/- 2%) but it was reduced at 10(-6) mol/l (7 +/- 2%; p < 0.05, n = 8). After asphyxia or ischemia, oxytocin did not dilate arterioles at 10(-8) mol/l, whereas 10(-6) mol/l resulted in a mild vasoconstriction (-4 +/- 3 to -6 +/- 4%, n = 6 and 8). Topically applied superoxide dismutase did not preserve arteriolar responses to oxytocin after asphyxia although the arterioles did not constrict to 10(-6) mol/l oxytocin (n = 5). Dilatation of cerebral arterioles in response to oxytocin was reversed to constriction by N(omega)-nitro-L-arginine methyl ester (L-NAME) (15 mg/kg, i.v.; n = 5) and by endothelial impairment by intra-arterial infusion of phorbol ester (10[-5] mol/l; n = 5). We conclude that the absence of pial arteriolar dilation to oxytocin after ischemia and asphyxia indicates endothelial dysfunction which may be involved in the pathology of perinatal brain injury.

The interaction between ATP-sensitive K+ channels (KATP) and nitric oxide (NO) was studied in pial arterioles of piglets. We examined the effects of N omega-nitro-L-arginine methyl ester (L-NAME), a general inhibitor of nitric oxide synthase (NOS), and 7-nitroindazole (7-NI), a selective inhibitor of neuronal NOS, on aprikalim-induced cerebral vasodilation. Topically applied, aprikalim, a selective activator of KATP, dilated arterioles by 11 +/- 7% at 10(-8) M and 17 +/- 6% at 10(-6) M. After L-NAME treatment (15 mg/kg, i.v.), the response was reduced (4 +/- 4% and 12 +/- 7%, respectively; n = 8, p < 0.05). Administration of 7-NI (50 mg/kg, i.p.) did not change pial arteriolar responsiveness to aprikalim. However, both L-NAME and 7-NI reduced the vasodilator responses to 10(-4) M N-methyl-D-aspartate (NMDA) (by 73% and by 36%, respectively). Furthermore, 7-NI treatment abolished the glutamate-induced dilatation of pial arterioles. Administration of L-NAME reduced the NOS activity in the cerebral cortex by 88%, whereas the reduction after the 7-NI treatment was 44%. Pre-treatment and coadministration of 10(-5) M glibenclaminde, a specific inhibitor of KATP or L-NAME administration, did not change the dilatory response to sodium nitroprusside. We conclude that NO may be involved in aprikalim-induced dilation of pial arterioles.

We examined the effects of total global ischemia on cerebral arteriolar responses to N-methyl-D-aspartate (NMDA) in anesthetized newborn pigs. Arteriolar responses to 10(-4) M NMDA were determined before and after 10 to 20 min of ischemia caused by increasing intracranial pressure. Before ischemia, NMDA dilated arterioles by 30 +/- 5% (baseline = 88 +/- 2 microns; n = 6). However, after 10 min of ischemia, arteriolar dilation was reduced to 10 +/- 3% at 1 h (P < 0.05). At 2 and 4 h, NMDA-induced dilation was not different from preischemia values. Twenty minutes of ischemia had similar effects. Coadministration of 100 U/ml of superoxide dismutase did not restore arteriolar dilation to NMDA at 1 h after ischemia. Sodium nitroprusside dilated by 14 +/- 3 and 40 +/- 5% at 10(-6) and 10(-5) M before ischemia, respectively, and arteriolar responsiveness was not changed by ischemia (n = 6). Cortical nitric oxide synthase (NOS) activity, measured by the in vitro conversion of L-[14C]arginine to L-[14C]citrulline, was unaffected by ischemia (n = 12). We conclude that decreases in cerebral arteriolar responsiveness to NMDA are not due to impairment of NOS activity, enhanced degradation or chelation of nitric oxide (NO), or reduced vascular smooth muscle responsiveness to NO.

Study Objectives: The aim of the study was to identify risk factors for early onset pneumonia (EOP) in trauma patients, in order to seek possible intervention strategies., Study Population: Participants included 124 consecutive trauma patients admitted to a general intensive care unit (ICU) of a university hospital from December 1990 to February 1992 inclusive., Data Collection: The following data were prospectively collected for each patient: demographics, severity of trauma according to the abbreviated injury scale (AIS), severity of coma according to the Glasgow coma scale (GCS), presence of pneumothorax, pulmonary contusion, rib fractures, hemothorax, and mechanical ventilation. All patients were monitored daily during the ICU stay for the onset of pneumonia, sepsis syndrome, septic shock, and adult respiratory distress syndrome (ARDS). Criteria for the diagnosis of pneumonia were: core temperature of greater than 38.3 degrees C, a WBC count of 10,000 cells/mm3, purulent tracheobronchial secretions, a worsening of pulmonary gas exchange, and persistent pulmonary infiltrates. All patients with suspected pneumonia underwent quantitative bronchoalveolar lavage (BAL) as well as blood cultures; BAL cultures were considered positive when they showed bacterial growth greater than 1 x 10(5) colony-forming unit (cfu)/ml, or less than 10(5), but with the same microorganism isolated in blood cultures. Pneumonia occurring within the first 96 h after trauma was considered EOP., Data Analysis: A stepwise logistic regression analysis was carried out in order to identify factors independently associated with an increased risk of EOP and late onset pneumonia (LOP)., Results: Overall mortality was 43.5 percent: mortality increased by age and AIS score. Forty one patients (33.1 percent) developed pneumonia: 26 (63.4 percent) were EOP and 15 (36.6 percent) were LOP. In the univariate analysis, an age greater than 40 years, the presence of pulmonary contusion, AIS of more than 4 for thorax and of more than 9 for abdomen, and the absence of mechanical ventilation (MV) during the first 4 days of hospitalization or MV lasting less than 24 h were significantly associated with an increased risk of acquiring EOP. Logistic regression analysis showed that the strongest risk factor for EOP was a combined severe abdominal and thoracic trauma, which increased the risk of EOP by 11 times; an age of more than 40 years and MV of less than 24 h during the first 4 days of hospitalization were also independent risk factors for EOP. Factors associated with LOP were an AIS score of more than 4 for abdomen and a length of MV of more than 5 days., Conclusion: In a trauma population, a combined severe abdominal and thoracic trauma represents a major risk factor for EOP. Mechanical ventilation administered during the first days after trauma seems to reduce the risk of EOP. As reported in previous studies, mechanical ventilatory support lasting more than 5 days is associated with an increased risk of LOP.

Auranofin [S-triethylphosphine gold-2,3,4,6 tetra-O-acetyl-l-thio-beta-D-glucopyranoside) SK&F 39162) has been administered at 0.1-0.25 mg/kg/day as the sole remission-inducing drug to 46 children affected with juvenile chronic arthritis (JCA). There were 22 males and 24 females; 12 children were affected with pauciarticular onset JCA, 26 with polyarticular onset JCA and 8 with systemic onset JCA. Three sets of efficacy criteria were evaluated quarterly: eight clinical, (Ritchie Index, number of affected, swollen and limited joints, number of joint with increased temperature, morning stiffness, Steinbrocker functional class, physician's disease evaluation), three hematochemical and one therapeutical. In most patients a panel of immunological parameters was routinely performed inclusive of peripheral blood lymphocyte subsets, serum immunoglobulins and C3c-C4 complement components. Patients who showed a definite improvement of at least two out of the three orders of efficacy criteria were classified as responders to auranofin. Out of the 35 patients evaluable after at least six months of treatment there were 24 (68%) responders. Nonresponders had a basal higher level of serum IgA and a basal lower level of serum C4. Both responders and nonresponders presented a reduction of the T4/T8 ratio during auranofin treatment, while only in responders did the basal high levels of IgG and C3c show a definite decrease.