bluuebunny/crossref_metadata_2025 huggingface dataset:
A kinetic study of UO2 dissolution and H2O2 stability in the presence of groundwater ions
Authors: Amme Marcus , Svedkauskaite J. , Bors W. , Murray M. , Merino J.
Published: November 2007

Current reactors spent nuclear UO2 fuel, that will probably enter geologic formations for disposal, is assumed to get into contact with groundwater of a repository earliest after several thousands of years. After this time, its alpha activity will be still high enough to induce a process of water radiolysis that leads to production of oxidants and, probably, to the oxidative dissolution of the material, that could start a mobilisation of radiotoxic nuclides. The main oxidant produced during this process would be hydrogen peroxide (H2O2), which is thermodynamically unstable and can decompose during reactions with certain groundwater ions. Information on the stability of H2O2 is therefore important for assessing the behaviour of the material in the repository.

We investigated the stability of H2O2 and the correlated dissolution of U from UO2 as a function of the concentration of H2O2 and of the groundwater ions carbonate, sulphate, and silicate. Decomposition of H2O2 was measured in the presence and absence of UO2(cr). We monitored the concentrations of H2O2, Udiss, groundwater ions, O2diss, and the pH in aqueous solution under Ar atmosphere. The lowest stabilities (in average) for H2O2 were found in carbonate solutions. When comparing the effect of carbonate systems containing UO2(cr) to carbonate solutions without a solid phase, we found that in some of the homogeneous tests H2O2 was consumed faster. This effect was not observed with the other groundwater ions. Also, U dissolution rates were significantly lower in the carbonate experiments than in those with sulphate or silicate. The results suggest that a radical-controlled mechanism (similar to the Halpern–Smith-mechanism of dissolved U(IV) oxidation) takes place at the UO2 surface during dissolution. The hypothesis is supported by ESR measurements on hydroxyl radical scavenging by the carbonate ion.
Kinetics and electrochemical studies of uranium in acetate and formate media by cyclic voltammetry
Authors: Khan A. S. A. , Ahmed Riaz , Mirza M. L.
Published: November 2007

The cyclic voltammetric behavior of uranyl ion was investigated at hanging mercury drop electrode in perchlorate supporting electrolyte. The standard heterogeneous electron transfer rate constant “ks” for the reduction of uranyl ion in perchlorate medium was (2.74±0.03)×10−3cm s−1while in acetate and formate medium the value ofkswas (2.83±0.02)×10−3and (2.66±0.02)×10−3cm s−1, respectively. The effect of temperature on the values ofkswas investigated and thermodynamic constants ΔH*, ΔS* and ΔG298* were evaluated. The values of ΔH*, ΔS*; and ΔG298* were 8.06±0.03 kJ mol−1, −23.42±0.05 J mol−1K−1and 15.02±0.07 kJ mol−1in simple perchlorate medium and 3.67±0.02 kJ mol−1, −38.04±0.05 J mol−1K−1, and 15.01±0.03 kJ mol−1in acetate medium and 0.79±0.02 kJ mol−1, −48.24±0.04 J mol−1K−1and 15.17±0.02 kJ mol−1in formate medium, respectively. The thermodynamic data showed that the process of reduction of uranyl ion at hanging mercury drop electrode was endothermic and non-spontaneous. The stability constants of uranyl acetate and uranyl formate were calculated from an analysis of the shift in peak potential data. The logβ1and logβ2values for 1:1 and 1:2 uranyl acetate complexes were 2.67±0.04 and 4.71±0.01, respectively. The values of logβ1and logβ2of uranyl formate complex were 1.61±0.02 and 2.57±0.01, respectively, which are reported for the first time.
The removal of polonium-210 and lead-210 from copper process streams by molybdenum-doped sodium tungstate
Authors: Secomb Rodney J. , Griffith Christopher S. , Brown Susan A. , Luca Vittorio
Published: November 2007

A molybdenum-doped sodium tungstate phase (Mo-HTB) and a porous, granular polyacrylonitrile composite variant (PAN-Mo-HTB) have been shown to effectively remove polonium-210 and lead-210 from concentrated sulphuric acid solutions (1–8 M) and a copper electrowinning electrolyte. Both forms of the exchanger were characterised by high polonium-210 and lead-210 distribution coefficients and very good selectivity for polonium-210 and lead-210 over divalent copper and iron.
Programmierbares Brückennormal zur Kalibrierung von Temperaturmessbrücken (Programmable Bridge Standard for Calibration of Thermometry Bridges)
Authors: Ramm Günther , Moser Harald , Vollmert Reinhold
Published: November 2007

Vorgestellt wird die Kalibrierung von AC-Temperaturmessbrücken mittels induktiver Brückennormale. Nach einer Beschreibung des Prinzips der Messbrücken und des Aufbaus von Brückennormalen wird der Kalibriervorgang erläutert, die Modellgleichung zur Berechnung der Messabweichung der Brücke hergeleitet und die zugehörige Messunsicherheit berechnet. Die vom Normal sowie von der Brücke verursachten Unsicherheitsbeiträge werden diskutiert. Abschließend wird die Kalibrierprozedur für das Brückennormal kurz erläutert und ein neues, programmierbares induktives Brückennormal präsentiert, mit dem Temperaturmessbrücken mit sehr kleinen Unsicherheiten automatisch kalibriert werden können.
Deflektometrische Rekonstruktion teilspiegelnder Freiformflächen (Deflectometric Reconstruction of Partially Specular Free-Form Surfaces)
Authors: Balzer Jonathan , Werling Stefan , Beyerer Jürgen
Published: November 2007

Bei der deflektometrischen Vermessung spiegelnder Bauteile erhält man ohne Zusatzwissen eine Mannigfaltigkeit von Lösungskandidaten. Im Fall, dass das untersuchte Objekt zusätzlich diffuse Reflexionsanteile besitzt, kann durch Einbeziehung der Reflektanzeigenschaften Eindeutigkeit erzwungen werden. Die Betrachtung charaketristischer Kurven in der Bildebene lässt die Bestimmung eines Oberflächenpunkts zu, von dem aus die gesuchte Fläche durch Integration erhalten werden kann. Die Praktikabilität des Ansatzes wird anhand experimenteller Ergebnisse gezeigt.
Neue Parameter zur Analyse der Störungen eines Coriolis-Massemessers (New Parameters for Analysis of Distortions of a Coriolis Mass Flow Meter)
Authors: Goeke Johannes , Stock Marc , Steffensen Erk
Published: November 2007

Alle Durchflussmesssysteme versagen bei der Messung von Zweiphasengemischen mit Gasen und Flüssigkeiten. Auch der Coriolis-Massemesser zeigt bereits bei kleinen Gasvolumina größer ein Prozent Abweichungen, die zu Ungenauigkeiten bei der Angabe des Massestroms und der Dichte führen.

In dieser Arbeit stellen wir die Ergebnisse einer spektralen Analyse der Schwingungen eines gestörten Coriolis-Massemessers vor. Ebenso zeigen wir Ergebnisse der Erregerströme und der Sensorspannungen für unterschiedliche Gasvolumina, Blasengrößen und Zusammensetzungen. Ebenso haben wir versucht, den Einfluss der Oberflächenspannung zu erfassen.

Zur Identifikation von Störungen durch die Gasphase werden Kennzahlen vorgeschlagen, die zur Korrektur der Störung beitragen können. Sie lassen sich darüber hinaus in ein Konzept einer vorbeugenden Wartung integrieren.
On a New Phase Transition in the Cu/Au(111)/H2SO4 System
Authors: Täubert C. E. , Petri M. , Kolb Dieter M.
Published: November 2007

A new pair of current spikes has been found in the cyclic voltammogram of Au(111) in an acidic copper sulphate solution, indicative of a phase transition in the Cu adlayer. The spike potential is well inside the bulk deposition region and hence, the new feature can be observed only at low Cu++ concentration, when bulk deposition is slow. The charge under the spike correlates linearly with extent of the (√3 × √3)R30° structure, up to 40μCcm-2 for the fully developed superstructure. The spike potential shifts with the sulphate concentration and hence, this feature is assigned to the desorption of sulphate from the well-known honey comb structure of the Cu upd layer.
Impact of fetal growth restriction on body composition and hormonal status at birth in infants of small and appropriate weight for gestational age
Authors: Verkauskiene R , Beltrand J , Claris O , Chevenne D , Deghmoun S , Dorgeret S , Alison M , Gaucherand P , Sibony O , Lévy-Marchal C
Published: November 2007

Background

Fetal growth restriction (FGR) has been related to several health risks, which have been generally identified in small-for-gestational age (SGA) individuals.

Objective

To evaluate the impact of FGR on body composition and hormonal status in infants born either small- or appropriate-for-gestational age (AGA).

Methods

Fetal growth was assessed by ultrasound every 4 weeks from mid-gestation to birth in 248 high-risk pregnancies for SGA. Fetal growth velocity was calculated as change in the estimated fetal weight percentiles and FGR defined as its reduction by more than 20 percentiles from 22 gestational weeks to birth. Impact of FGR on body composition, cord insulin, IGF-I, IGF binding protein-3 (IGFBP-3), and cortisol concentrations was assessed in SGA and AGA newborns.

Results

Growth-retarded AGA infants showed significantly reduced birth weight, ponderal index, percentage of fat mass, and bone mineral density when compared with AGA newborns with stable intrauterine growth. Cord IGF-I and IGFBP-3 concentrations were significantly decreased in growth-retarded infants in both SGA and AGA groups. Cord insulin concentration was significantly lower and cord cortisol significantly higher in AGA infants with FGR versus AGA newborns with stable intrauterine growth.

After adjustment for gestational age and gender, birth weight was directly related to fetal growth velocity and cord IGF-I concentration. The variation in infant's adiposity was best explained by fetal growth velocity and cord insulin concentration.

Conclusions

FGR affects body composition and hormonal parameters in newborns with birth weight within the normal range, suggesting these individuals could be at similar metabolic risks as SGA.
Central laboratory reassessment of IGF-I, IGF-binding protein-3, and GH serum concentrations measured at local treatment centers in growth-impaired children: implications for the agreement between outpatient screening and the results of somatotropic axis functional testing
Authors: Hauffa Berthold P , Lehmann Nils , Bettendorf Markus , Mehls Otto , Dörr Helmuth-Günther , Stahnke Nikolaus , Steinkamp Heinz , Said Elfriede , Ranke Michael B , _ _
Published: November 2007

Background

Childhood GH deficiency, suspected in the presence of decreased height velocity and short stature, is usually characterized by low IGF-I and IGF-binding protein-3 (IGFBP-3) serum concentrations and is conventionally confirmed by diminished GH peak responses to pharmacological stimuli.

Objective

We evaluated the agreement between different IGF-I (IGFBP-3) assays in predicting GH deficiency and tested whether variability between growth factor screening and pharmacological testing could be diminished by reassessment of growth factor and GH peak concentrations in a single laboratory.

Design

Using the Tuebingen IGF-I (IGFBP-3) RIA, 317 (321) sera from children evaluated for growth disorders in 19 centers were reanalyzed. In 103 children with insulin hypoglycemia and arginine tests, we evaluated how the association between the outcome of growth factor screening and functional testing would change if different assays were employed.

Results

Locally measured IGF-I correlated better than IGFBP-3 with the results of the central laboratory (Tuebingen) assay (slope of the regression curve 1.05; 95% confidence interval (95% CI) 1.01–1.1 versus 1.18; 95% CI 1.09–1.3). Agreement between local and central laboratory assays in predicting GH deficiency was better for IGF-I than for IGFBP-3 assays (κ=0.59 versus κ=0.47). The poor agreement between growth factor screening and GH pharmacological testing was not improved when hormone concentrations were remeasured in the central laboratory (κ local=−0.0031, central=0.12).

Conclusions

In children with impaired growth, growth factor screening reflects different aspects of GH insufficiency than does functional testing. Agreement between these approaches is poor and could not be improved by reduction of assay-related variability.
Impact of the primary aetiology upon the clinical outcome of adults with childhood-onset GH deficiency
Authors: Hoybye Charlotte , Jönsson Peter , Monson John P , Kołtowska-Häggström Maria , Hána Václav , Geffner Mitchell , Abs Roger
Published: November 2007

Objective

The impact of the aetiology of childhood-onset GH deficiency (CO-GHD) on the clinical presentation during adulthood and the response to GH replacement has been poorly defined. Our study aims to characterize CO-GHD in adults due to different aetiologies and evaluate the effect of 2 years of GH replacement therapy.

Design and methods

Data from 353 adults with CO-GHD from Pfizer International Metabolic Database KIMS were retrospectively grouped according to GHD aetiology: non-organic disorder (n=147), organic pituitary disease (n=159), and brain tumour (n=47). Extent of pituitary dysfunction, IGF-I concentration, lipid concentrations and quality-of-life (QoL) were assessed at baseline and after 2 years of GH replacement.

Results

GHD was diagnosed at a later age in the organic pituitary group than in the other groups, resulting in a shorter duration of GH treatment during childhood. However, the final height was greater in the organic pituitary group. Panhypopituitarism was most common in the non-organic disorder and in the organic pituitary groups, while isolated GHD was more prominent in the brain tumour group. Serum IGF-I levels were the lowest in the non-organic group. QoL was the poorest in the brain tumour group. Lipid profile and QoL improved significantly during GH replacement.

Conclusion

The adverse consequences of CO-GHD in adulthood vary between aetiologies, but improve similarly with GH treatment. It is, therefore, important to consider retesting all patients with CO-GHD in early adulthood and, if persistent severe GHD is confirmed, recommence GH replacement.
Optimalization and cost management of lanreotide-Autogel therapy in acromegaly
Authors: Abrams Pascale , Alexopoulou Orsalia , Abs Roger , Maiter Dominique , Verhelst Johan
Published: November 2007

Background

Lanreotide-Autogel is a depot formulation of the somatostatin analog lanreotide used in the treatment of acromegaly. We investigated whether prolonging or shortening the interval between injections would offer any benefit.

Subjects and methods

The interval was prolonged from once every 4 weeks to once every 6 weeks when patients (n=9) had normal IGF-I and GH concentrations. When patients (n=12) had still elevated IGF-I or GH on the maximal dose of 120 mg every 4 weeks, the interval was shortened to once every 3 weeks. Serum IGF-I and GH were measured after 12 and 24 weeks to allow for dose adaptation. Symptoms and tumor volume were evaluated at baseline and after 36 weeks.

Results

In seven of the nine subjects with normal IGF-I and GH, the interval could be extended to 6 weeks without loosing efficacy on IGF-I (195 vs 213 μg/l; not significant, NS) and GH concentrations (1.4 vs 1.3 μg/l; NS). The weekly dose could significantly be reduced (from 23.3 to 17.8 mg; P=0.002). In only 1 of the 12 not-controlled patients, reducing the interval to once every 3 weeks induced normalization of IGF-I and GH.

Conclusion

In subjects whose acromegaly is well controlled using lanreotide-Autogel, prolonging the time interval between injections can often be increased 4 to 6 weeks without loss of efficacy, thereby improving the subject's comfort and reducing the cost of treatment. On the other hand, in subjects whose acromegaly is not controlled on a dose of 120 mg every 4 weeks, reducing the interval to every 3 weeks is rarely beneficial.
Beneficial effect of dose escalation of Octreotide-LAR as first-line therapy in patients with acromegaly
Authors: Colao Annamaria , Pivonello Rosario , Auriemma Renata S , Galdiero Mariano , Savastano Silvia , Lombardi Gaetano
Published: November 2007

Objective

To evaluate the efficacy of dose escalation of Octreotide-long-acting repeatable (LAR) up to 40 mg/month we studied 56 newly diagnosed patients with acromegaly (24 women, 32 men; age 20–82 years).

Design

Analytical, observational, open and prospective.

Methods

Three months after LAR treatment beginning with a dose of 20 mg /q28d (every 28 days), 24 patients maintained the same dose (Group A), while 32 required a dose of 30 mg/q28d (Group B). The dose was further increased to 40 mg/q28d in 17 out of the 32 patients of Group B for another 12 months (Group C).

Results

After 24 months, serum GH and IGF-I levels decreased by 93.1±8.6% (95% confidence limit (CL) 90.8–95.4%) and 62.7±13.4% (95% CL 59.1–66.3%) respectively. Control of GH and IGF-I levels was achieved in 45 patients (80.3%). Tumor shrinkage after 12 months was 49.8±23%; the relative tumor shrinkage during the second 12 months of treatment was 35.3±13.1% and overall tumor volume was 68.1±16.5% (95% CL 63.7–72.5%). Glucose tolerance impaired in eight patients (14.3%): four in Group A and four in Group C (16.7% vs 36.4%,P=0.39).

The final dose was predicted by the patient's age at diagnosis (t=−2.2;P=0.032) and baseline tumor volume (t=2.1;P=0.043).

Conclusion

An increase of the LAR dose up to 40 mg/q28d in patients resistant to 30 mg/q28d is followed by greater suppression of GH and IGF-I levels and tumor shrinkage without further significant impairment of glucose tolerance when compared with lower doses. These results suggest that a new dosage schedule of 40 mg every 28 days is applied in patients with acromegaly mostly of young age and with bigger tumors who are likely to be poorly responsive to standard doses of Octreotide-LAR.
Polymorphisms in the interleukin-6 receptor gene are associated with bone mineral density and body mass index in Spanish postmenopausal women
Authors: Bustamante M , Nogués X , Mellibovsky L , Agueda L , Jurado S , Cáceres E , Blanch J , Carreras R , Díez-Pérez A , Grinberg D , Balcells S
Published: November 2007

Objective

Osteoporosis and obesity are complex diseases with a strong genetic component. Bone mineral density (BMD) and body mass index (BMI) linkage studies identified a locus at 1q21-23, where the interleukin-6 receptor (IL6R) gene is located. The IL6R and the gp130 receptors are the mediators of IL6 action. Serum levels of IL6 and sIL6R (the soluble form of IL6R) are higher in several diseases such as osteoporosis or obesity. Variants atIL6Rhave been associated with BMI and obesity. However,IL6Ris an as-yet-unexplored osteoporosis candidate gene.

Design

In the present study we analysed two polymorphisms in theIL6Rpromoter, −1435 C/T (rs3887104) and −208 G/A (rs4845617), and the Asp358Ala polymorphism (rs8192284), in relation to both BMD and BMI in a cohort of 559 postmenopausal Spanish women.

Results

The promoter polymorphisms, −1435 C/T and −208 G/A were associated with femoral neck (FN) BMD (P=0.011 andP=0.025 respectively). The C-A and T-G promoter haplotypes were also associated with FN BMD. Additionally, the Asp358Ala variant was associated with lumbar spine BMD (P=0.038). Finally, the −208 G/A polymorphism and the C-G and C-A haplotypes were associated with BMI and obesity, where GG was the risk genotype (P=0.033 for BMI;P=0.010 for obesity).

Conclusion

These data suggest that variants in theIL6Rgene are not only involved in the determination of BMI but also relevant for the determination of BMD. TheIL6Rgene may belong to the growing list of genes known to be involved in both phenotypes.
Evaluation of insulin resistance in a cohort of HIV-infected youth
Authors: Rosso Raffaella , Parodi Arianna , d'Annunzio Giuseppe , Ginocchio Francesca , Nicolini Laura , Torrisi Chiara , Pia Sormani Maria , Lorini Renata , Viscoli Claudio , Vignolo Marina
Published: November 2007

Objective

Metabolic abnormalities, including impairment of glucose homeostasis, have been well characterized in HIV-infected patients. In contrast to adults, insulin resistance and diabetes mellitus appear to be relatively uncommon finding in youth.

Design

We assessed insulin resistance, and associated risk factors, in a population of vertically HIV-infected children and young adults, when compared with a control population of healthy children.

Methods

At the time of enrolment, weeks of pregnancy, birth weight, sex, age, weight, height, body mass index (BMI), pubertal stages, CDC classification, blood pressure, clinical lipodystrophy, hepatitis B or C co-infection, antiretroviral therapy, CD4 T lymphocyte counts, and HIV-RNA levels were recorded. Fasting plasma glucose and insulin levels and homeostatic model assessment-insulin resistance (HOMA-IR) were determined. These parameters were compared between HIV patients and healthy controls with multivariate analyses.

Results

Fasting insulin levels (OR=1.21,P<0.001) and glycemia (OR=0.89,P<0.001) were significantly different between HIV-infected patients and controls. Antiretroviral therapy duration (r=0.281,P<0.05), triglyceride levels (r=0.286,P<0.05), age (r=0.299,P<0.05), and BMI SDS (r=0.485,P<0.001) were significant predictor variables of insulin resistance, expressed as HOMA-IR. Moreover, clinical lipodystrophy seems to be strongly correlated to glycemia (P<0.05), triglyceride levels (P<0.05), serum insulin levels (P<0.001), HOMA-IR (P<0.05), and also with therapy duration (P<0.05).

Conclusions

Both HIV infection and antiretroviral therapy demonstrate differential effects on glucose metabolism in HIV-infected children. Targeted prevention of insulin resistance and diabetes mellitus in HIV-infected children and young adults is needed in order to avoid the associated long-term complications that would otherwise occur, given the improvement in life expectancy of HIV-infected individuals.
Does Providing Human Milk for Her Very Low-birthweight Infant Help the Mother?
Authors: Furman Lydia
Published: November 2007

Benefits accrued to the mother of a very low-birthweight (VLBW) infant who is providing human milk for her infant are likely to include many of the positive health effects that mothers of term infants enjoy, such as a reduced risk of breast and ovarian cancer. Whether breastfeeding decreases the risk of postpartum depression, improves maternal mood, or reduces stress and anxiety has not yet been documented. The diversity of experiences that can be described as “breastfeeding” a VLBW infant, including milk expression with a pump, skin-to-skin care with nuzzling, and feeding directly at the breast, adds complexity to research in this area. There is no evidence that providing human milk or encouraging a mother to provide human milk is harmful in any way. Clinicians can and should support breastfeeding and human milk provision among mothers of VLBW infants.
Interpreting and Managing Blood Lead Levels of Less Than 10 μg/dL in Children and Reducing Childhood Exposure to Lead: Recommendations of the Centers for Disease Control and Prevention Advisory Committee on Childhood Lead Poisoning Prevention
Authors: Binns Helen J. , Campbell Carla , Brown Mary Jean ,   for the Advisory Committee on Childhood Lead Poisoning Prevention
Published: November 2007

Lead is a common environmental contaminant. Lead exposure is a preventable risk that exists in all areas of the United States. In children, lead is associated with impaired cognitive, motor, behavioral, and physical abilities. In 1991, the Centers for Disease Control and Prevention defined the blood lead level that should prompt public health actions as 10 μg/dL. Concurrently, the Centers for Disease Control and Prevention also recognized that a blood lead level of 10 μg/dL did not define a threshold for the harmful effects of lead. Research conducted since 1991 has strengthened the evidence that children's physical and mental development can be affected at blood lead levels of <10 μg/dL. In this report we provide information to help clinicians understand blood lead levels < 10 μg/dL, identify gaps in knowledge concerning lead levels in this range, and outline strategies to reduce childhood exposures to lead. We also summarize scientific data relevant to counseling, blood lead screening, and lead-exposure risk assessment. To aid in the interpretation of blood lead levels, clinicians should understand the laboratory error range for blood lead values and, if possible, select a laboratory that achieves routine performance within ±2 μg/dL. Clinicians should obtain an environmental history on all children they examine, provide families with lead-prevention counseling, and follow blood lead screening recommendations established for their areas. As circumstances permit, clinicians should consider referral to developmental programs for children at high risk for exposure to lead and more frequent rescreening of children with blood lead levels approaching 10 μg/dL. In addition, clinicians should direct parents to agencies and sources of information that will help them establish a lead-safe environment for their children. For these preventive strategies to succeed, partnerships between health care providers, families, and local public health and housing programs should be strengthened.
Guidelines for Adolescent Depression in Primary Care (GLAD-PC): II. Treatment and Ongoing Management
Authors: Cheung Amy H. , Zuckerbrot Rachel A. , Jensen Peter S. , Ghalib Kareem , Laraque Danielle , Stein Ruth E.K. ,   and the GLAD-PC Steering Group
Published: November 2007

OBJECTIVES. To develop clinical practice guidelines to assist primary care clinicians in the management of adolescent depression. This second part of the guidelines addresses treatment and ongoing management of adolescent depression in the primary care setting.

METHODS. Using a combination of evidence- and consensus-based methodologies, guidelines were developed in 5 phases as informed by (1) current scientific evidence (published and unpublished), (2) a series of focus groups, (3) a formal survey, (4) an expert consensus workshop, and (5) revision and iteration among members of the steering committee.

RESULTS. These guidelines are targeted for youth aged 10 to 21 years and offer recommendations for the management of adolescent depression in primary care, including (1) active monitoring of mildly depressed youth, (2) details for the specific application of evidence-based medication and psychotherapeutic approaches in cases of moderate-to-severe depression, (3) careful monitoring of adverse effects, (4) consultation and coordination of care with mental health specialists, (5) ongoing tracking of outcomes, and (6) specific steps to be taken in instances of partial or no improvement after an initial treatment has begun. The strength of each recommendation and its evidence base are summarized.

CONCLUSIONS. These guidelines cannot replace clinical judgment, and they should not be the sole source of guidance for adolescent depression management. Nonetheless, the guidelines may assist primary care clinicians in the management of depressed adolescents in an era of great clinical need and a shortage of mental health specialists. Additional research concerning the management of youth with depression in primary care is needed, including the usability, feasibility, and sustainability of guidelines and determination of the extent to which the guidelines actually improve outcomes of youth with depression.
Altered Resting Cerebral Blood Flow in Adolescents With in Utero Cocaine Exposure Revealed by Perfusion Functional MRI
Authors: Rao Hengyi , Wang Jiongjiong , Giannetta Joan , Korczykowski Marc , Shera David , Avants Brian B. , Gee James , Detre John A. , Hurt Hallam
Published: November 2007

OBJECTIVES. Animal studies have clearly demonstrated the effects of in utero cocaine exposure on neural ontogeny, especially in dopamine-rich areas of cerebral cortex; however, less is known about how in utero cocaine exposure affects longitudinal neurocognitive development of the human brain. We used continuous arterial spin-labeling perfusion functional MRI to measure the effect of in utero cocaine exposure on resting brain function by comparing resting cerebral blood flow of cocaine-exposed adolescents with non–cocaine-exposed control subjects.

PATIENTS AND METHODS. Twenty-four cocaine-exposed adolescents and 25 matched non–cocaine-exposed control subjects underwent structural and perfusion functional MRI during resting states. Direct subtraction, voxel-wise general linear modeling, and region-of-interest analyses were performed on the cerebral blood flow images to compare the resting cerebral blood flow between the 2 groups.

RESULTS. Compared with control subjects, cocaine-exposed adolescents showed significantly reduced global cerebral blood flow. The decrease of cerebral blood flow in cocaine-exposed adolescents was observed mainly in posterior and inferior brain regions, including the occipital cortex and thalamus. After adjusting for global cerebral blood flow, however, a significant increase in relative cerebral blood flow in cocaine-exposed adolescents was found in anterior and superior brain regions, including the prefrontal, cingulate, insular, amygdala, and superior parietal cortex. Furthermore, the functional modulations by in utero cocaine exposure on all of these regions except amygdala cannot be accounted for by the variation in brain anatomy.

CONCLUSIONS. In utero cocaine exposure may reduce global cerebral blood flow, and this reduction may persist into adolescence. The relative increase of cerebral blood flow in anterior and superior brain regions in cocaine-exposed adolescent participants suggests that compensatory mechanisms for reduced global cerebral blood flow may develop during neural ontogeny. Arterial spin-labeling perfusion MRI may be a valuable tool for investigating the long-term effects of in utero drug exposure.
Impact of Size at Birth on the Microvasculature: The Avon Longitudinal Study of Parents and Children
Authors: Tapp Robyn J. , Williams Cathy , Witt Nicholas , Chaturvedi Nish , Evans Richard , Thom Simon A. McG , Hughes Alun D. , Ness Andrew
Published: November 2007

BACKGROUND. The impact of early life factors on the microvasculature is relatively unknown.

OBJECTIVES. We hypothesized that small birth size may be associated with structural variations in the retinal vasculature in children.

METHODS. The Avon Longitudinal Study of Parents and Children followed a cohort of children born in 1991–1992 from birth. The current study included the first 263 children who were systematically screened in the year-12 follow-up. Complete data were available for 166 children with a gestation of ≥37 weeks. Retinal circulatory measures were evaluated, including retinal microvascular tortuosity and bifurcation optimality deviance, an indicator of abnormal endothelial function.

RESULTS. Optimality deviance and retinal tortuosity were higher among those with lower birth weight. Linear regression modeling was used to assess the association of retinal microvascular measures with birth weight. The standardized β coefficient between optimality deviance and birth weight was −.182 adjusted for gender and age in weeks; additional adjustment for systolic blood pressure and heart rate had little impact on the β coefficient. A similar association was observed for retinal tortuosity.

CONCLUSION. The findings of this study suggest that early life factors may have an important impact on retinal vascular structure, possibly through an adverse effect on endothelial function.
Burden of Acute Sore Throat and Group A Streptococcal Pharyngitis in School-aged Children and Their Families in Australia
Authors: Danchin Margaret H. , Rogers Susan , Kelpie Loraine , Selvaraj Gowri , Curtis Nigel , Carlin John B. , Nolan Terence M. , Carapetis Jonathan R.
Published: November 2007

OBJECTIVE. The objective of this study was to determine the incidence, transmission, carriage, and risk factors for group A streptococcal pharyngitis in school-aged children and their families.

METHODS. A 16-month, prospective, family-based cohort study was undertaken from August 2001 through December 2002 in Melbourne, Australia. A total of 202 families (853 people) with at least 1 child aged 3 to 12 years were randomly selected from 3 primary care practices across suburban Melbourne to collect surveillance data for acute group A streptococcal pharyngitis, including serology for index and secondary cases and intermittent carriage data. Cohort retention was 97% for 16 months.

RESULTS. The incidence of acute sore throat, group A streptococcal swab–positive pharyngitis, and serologically confirmed group A streptococcal pharyngitis was 33, 13, and 8 per 100 child-years, respectively, for school-aged children (5–12 years) and 60, 20, and 15 per 100 family-years, respectively. Sore throat was less common in adults than children, but adults with sore throat were as likely as children to have group A streptococcal culture–positive or serologically proven pharyngitis. In families who had a primary case, 43% had at least 1 secondary case, and in family members who were at risk, 13% contracted a secondary case. The spring, summer, and winter carriage rates for children were 13%, 8%, and 16%, respectively, and for adults the rate was 2% across all seasons.

CONCLUSIONS. Group A streptococcal pharyngitis is still common, and the peak incidence occurs in school-aged children. However, the incidence in adults is higher than expected, and the number of secondary cases in families may be an important factor when considering the potential benefits of treatment.
Atypical Tetanus in a Completely Immunized 14-Year-Old Boy
Authors: König Kai , Ringe Hannelore , Dorner Brigitte G. , Diers Alexander , Uhlenberg Birgit , Müller Dominik , Varnholt Verena , Gaedicke Gerhard
Published: November 2007

We report the uncommon clinical course of tetanus in a completely immunized 14-year-old boy. His initial symptoms, which included a flaccid paralysis, supported a diagnosis of botulism. Preliminary mouse-test results with combined botulinum antitoxins A, B, and E, obtained from tetanus-immunized horses, backed this diagnosis. The change in his clinical course from paralysis to rigor and the negative, more specific, botulinum mouse test with isolated botulinum antitoxins A, B, and E, obtained from nonvaccinated rabbits, disproved the diagnosis of botulism. Tetanus was suspected despite complete vaccination. The final results of a positive mouse test performed with isolated tetanus antitoxin confirmed the diagnosis. Adequate treatment was begun, and the boy recovered completely.
Is Childhood Vaccination Associated With Asthma? A Meta-analysis of Observational Studies
Authors: Balicer Ran D. , Grotto Itamar , Mimouni Marc , Mimouni Daniel
Published: November 2007

BACKGROUND. The possible link between immunization and atopic diseases has been under intense debate in the last decade.

OBJECTIVE. The aim of this study was to systematically review the available evidence on the association of whole-cell pertussis and BCG vaccination with the risk of asthma in childhood and adolescence.

METHODS. The major medical electronic databases (Medline, National Library of Medicine Gateway, and Cochrane Library) were searched, and reference lists of the relevant publications were reviewed for relevant birth-cohort studies and randomized, controlled trials from 1966 to March 2006. Only studies that directly compared vaccinated and unvaccinated children, validated vaccination status by medical charts, and used preset criteria to define asthma were included. Data were abstracted by using a standardized protocol and computerized report form. Results were analyzed by applying a fixed-effect or random-effect model, according to the heterogeneity of the studies. Sensitivity analyses by scoring criteria were performed.

RESULTS. Seven studies of pertussis vaccination (with a total of 186663 patients) and 5 studies of BCG vaccination (with a total of 41479 patients) met our inclusion criteria. No statistically significant association was detected between either whole-cell pertussis or BCG vaccination and incidence rates of asthma during childhood and adolescence. This lack of a significant association proved to be robust on sensitivity analyses for BCG but not for pertussis vaccine.

CONCLUSIONS. Currently available data, based on observational studies, do not support an association, provocative or protective, between receipt of the BCG or whole-cell pertussis vaccine and risk of asthma in childhood and adolescence.
Health Status and Health-Related Quality of Life Preference-Based Outcomes of Children Who Are Aged 7 to 9 Years and Have Bilateral Permanent Childhood Hearing Impairment
Authors: Petrou Stavros , McCann Donna , Law Catherine M. , Watkin Peter M. , Worsfold Sarah , Kennedy Colin R.
Published: November 2007

OBJECTIVE. The objective of this study was to describe the health status and health-related quality of life preference-based outcomes of children with diagnosed bilateral permanent childhood hearing impairment and a comparison group of English-speaking children with normal hearing.

METHODS. We studied 120 children who were aged 7 to 9 years and had bilateral permanent childhood hearing impairment of moderate or greater severity, identified from a cohort of 156733 children who were born in 8 districts of southern England, and 63 English-speaking children with normal hearing and the same place of birth and age at assessment. Principal caregivers were interviewed by using the Health Utilities Index Mark III questionnaire for proxy-assessed usual health status assessment. Levels of function within each of the 8 attributes of the Health Utilities Index Mark III (cognition, vision, hearing, speech, ambulation, dexterity, emotion, and pain) were recorded.

RESULTS. Bilateral permanent childhood hearing impairment is associated with significantly increased proportions of suboptimal levels of function and significantly lower single-attribute utility scores in 6 of the 8 attributes of the Health Utilities Index Mark III: vision, hearing, speech, ambulation, dexterity, and cognition. Compared with the children with normal hearing, the mean multiattribute utility score for the children with hearing impairment was significantly lower for both the whole group and the moderate, severe, and profound severity subgroups. The differences in the distributions of the multiattribute utility scores between the children with hearing impairment as a group and the children with normal hearing and between each of the severity subgroups and the children with normal hearing all were statistically significant.

CONCLUSIONS. This study provides rigorous evidence of an association between bilateral permanent childhood hearing impairment and diminished health status and health-related quality of life preference-based outcomes during midchildhood.
Newborn Screening for Pompe Disease: Synthesis of the Evidence and Development of Screening Recommendations
Authors: Kemper Alex R. , Hwu Wuh-Liang , Lloyd-Puryear Michele , Kishnani Priya S.
Published: November 2007

BACKGROUND. Pompe disease is a lysosomal storage disorder that leads to the accumulation of glycogen and subsequently to muscle weakness, organ damage, and death. Pompe disease is detectable through newborn screening, and treatment has become available recently.

OBJECTIVE. Our goal was to review systematically all available evidence regarding screening for infantile Pompe disease to help policy makers determine whether Pompe disease should be added to their state's newborn screening battery.

METHODS. We searched online databases, including Medline, clinicaltrials.gov, and the Computer Retrieval of Information on Scientific Projects database, as well as Web sites maintained by federal organizations (eg, the Food and Drug Administration) and other nonprofit or private organizations (eg, the March of Dimes and Genzyme Corp), by using the terms “glycogen storage disease type II,” “Pompe disease,” and “Pompe's disease.” We also obtained preliminary findings from a screening program in Taiwan. Data were critically appraised and extracted by 2 investigators, one who is an expert in systematic review methods and the other who is an expert in Pompe disease.

RESULTS. The prevalence of Pompe disease has been estimated to be ∼1 case per 40000. Small studies suggest that enzyme therapy is highly efficacious in infantile Pompe disease and that earlier intervention leads to improved outcomes. Screening cannot distinguish between infantile and late-onset Pompe disease. The current screening program in Taiwan has a high false-positive rate; however, the threshold was purposely set low to ensure that no case would be missed.

CONCLUSIONS. Pilot studies of screening are needed to identify the most efficacious strategy for screening and determine how to manage cases of late-onset Pompe disease before screening for Pompe disease is adopted widely by newborn screening programs.
Impact of Singular Excessive Computer Game and Television Exposure on Sleep Patterns and Memory Performance of School-aged Children
Authors: Dworak Markus , Schierl Thomas , Bruns Thomas , Strüder Heiko Klaus
Published: November 2007

OBJECTIVE. Television and computer game consumption are a powerful influence in the lives of most children. Previous evidence has supported the notion that media exposure could impair a variety of behavioral characteristics. Excessive television viewing and computer game playing have been associated with many psychiatric symptoms, especially emotional and behavioral symptoms, somatic complaints, attention problems such as hyperactivity, and family interaction problems. Nevertheless, there is insufficient knowledge about the relationship between singular excessive media consumption on sleep patterns and linked implications on children. The aim of this study was to investigate the effects of singular excessive television and computer game consumption on sleep patterns and memory performance of children.

METHODS. Eleven school-aged children were recruited for this polysomnographic study. Children were exposed to voluntary excessive television and computer game consumption. In the subsequent night, polysomnographic measurements were conducted to measure sleep-architecture and sleep-continuity parameters. In addition, a visual and verbal memory test was conducted before media stimulation and after the subsequent sleeping period to determine visuospatial and verbal memory performance.

RESULTS. Only computer game playing resulted in significant reduced amounts of slow-wave sleep as well as significant declines in verbal memory performance. Prolonged sleep-onset latency and more stage 2 sleep were also detected after previous computer game consumption. No effects on rapid eye movement sleep were observed. Television viewing reduced sleep efficiency significantly but did not affect sleep patterns.

CONCLUSIONS. The results suggest that television and computer game exposure affect children's sleep and deteriorate verbal cognitive performance, which supports the hypothesis of the negative influence of media consumption on children's sleep, learning, and memory.
Association Between Iron-Deficiency Anemia and Stroke in Young Children
Authors: Maguire Jonathon L. , deVeber Gabrielle , Parkin Patricia C.
Published: November 2007

OBJECTIVE. Iron-deficiency anemia occurs with a peak prevalence of 4% to 8% in children between 1 and 3 years of age. Case reports have suggested an association between iron-deficiency anemia in healthy children and ischemic stroke. Our objective was to investigate whether iron-deficiency anemia is associated with stroke in young children.

METHODS. A case-control study was conducted of case patients who were selected from the stroke registry at the Hospital for Sick Children (Toronto, Ontario, Canada) and control subjects selected from a database of healthy children who were prospectively enrolled in an outpatient setting. Children were aged 12 to 38 months and were previously healthy with no identifiable risk factors for stroke. Age, gender, mean corpuscular volume, platelet count, and hemoglobin and ferritin levels were collected. Iron-deficiency anemia was defined as a hemoglobin level of <110 g/L, mean corpuscular volume <73 fL, and serum ferritin level <12 μg/L. Stroke was defined according to clinical and radiologic criteria.

RESULTS. Case (n = 15) and control (n = 143) subjects were similar with respect to median age and percentage of boys. Case patients had a lower median hemoglobin level and mean corpuscular volume and a higher median platelet count. Iron-deficiency anemia was significantly more common among case patients (8 [53%] of 15) than control subjects (13 [9%] of 143).

CONCLUSIONS. Previously healthy children with stroke were 10 times more likely to have iron-deficiency anemia than healthy children without stroke. Furthermore, children with iron-deficiency anemia accounted for more than half of all stroke cases in children without an underlying medical illness, which suggests that iron-deficiency anemia is a significant risk factor for stroke in otherwise healthy young children. Primary prevention and early identification of iron-deficiency anemia must remain a priority.
Neonatal Renal Vein Thrombosis: Review of the English-Language Literature Between 1992 and 2006
Authors: Lau Keith K. , Stoffman Jayson M. , Williams Suzane , McCusker Patricia , Brandao Leonardo , Patel Sanjay , Chan Anthony K.C. ,   for the Canadian Pediatric Thrombosis and Hemostasis Network
Published: November 2007

Renal vein thrombosis is a complication that occurs in neonates with various underlying risk factors. It carries a grave prognosis for affected kidneys. Anticoagulant and fibrinolytic therapies have been promoted in the past with anecdotal success in some circumstances. However, prospective controlled trials are still lacking, and to date there have been no evidence-based guidelines available for the treatment of neonates with renal vein thrombosis. We retrospectively reviewed all the available medical literature pertaining to renal vein thrombosis published in English during the past 15 years. A total of 271 patients from 13 case series were identified by using the terms “renal vein thrombosis” and “neonates” via PubMed and Cochrane Library searches. Data then were extracted from each of the studies for analysis. During the past 15 years, a male predominance (67.2%) in neonatal renal vein thrombosis has been reported. More than 70% of patients had unilateral renal vein thrombosis, which was more prevalent on the left side (63.6%). The thrombus involved the inferior vena cava and was associated with adrenal hemorrhage in 43.7% and 14.8% of neonates, respectively. Forty percent of the patients were treated conservatively with supportive care alone. Among those patients who received anticoagulation therapy, unfractionated heparin and low molecular weight heparin were used alone in 21.6% and 20.7% of the patients, respectively. Fibrinolytic treatment alone was used in 11.2% of the patients. Only a minority of patients were treated with antithrombin (1.7%), warfarin alone, (0.9%) or underwent surgical intervention (0.3%). The majority (70.6%) of the involved kidneys became atrophic. A total of 9 neonates died with non–renal vein thrombosis–related conditions during the study period. Evidence-based recommendations on treatment cannot be made at the present time. Cooperative prospective studies that involve multiple centers are needed to elucidate the optimal treatment for neonatal renal vein thrombosis.