Advertising Exposure From Online and Offline Sources and Youth Tobacco Use: Findings From the Adolescents, Place, and Behavior Study.

INTRODUCTION: Tobacco use among adolescents is an ongoing public health concern. Youth tobacco use has been associated with advertising, from both online sources and retail environments. AIMS AND METHODS: This study examined associations between exposure to tobacco advertisements from tobacco retail outlets (TROs), internet, and social media sources and ever tobacco use among adolescents. Data were obtained from youth, aged 11-17 years (N = 401) from Richmond, VA. Bayesian index and group index models were fitted to estimate indices of exposure to (1) social media use, (2) tobacco ads on social media, and (3) TRO store visits and their association with ever tobacco use. The most important components of the exposure indices were also determined based on the index component weights from the Bayesian index models. RESULTS: In Bayesian index models of single exposures, each exposure index was significantly associated with tobacco use. In the best-fitting model, social media tobacco ads (odds ratio [OR] = 2.2; 95% credible interval [CI]: 1.2, 4.5) and TRO store visits (OR = 1.6; 95% CI: 1.1, 2.3) were significantly associated with ever tobacco use, as was older age (OR = 1.4; 95% CI: 1.2, 1.8). Index component weights revealed Snapchat ad frequency as the most important platform in the social media index and convenience stores as the most important type of store in the TRO index. CONCLUSIONS: Exposure to pro-tobacco advertisements on social media and visits to TROs are associated with adolescent ever tobacco use. Results provide support for policies that would restrict the promotion of tobacco products at TROs and on social media. Tobacco regulations and interventions targeting convenience stores and Snapchat may be warranted to reduce youth tobacco use. IMPLICATIONS: Current evidence provide support for policies that would restrict the promotion of tobacco products at TROs and on social media. Findings suggest that regulations and interventions that specifically target advertisements in convenience stores and on Snapchat may be currently warranted to reduce youth tobacco use.

Dental Infections and Risk for Brain Abscess: A Literature Review.

Dental work is commonly accepted as a low-risk procedure but has been associated with serious brain abscesses. Bacteria from the oral cavity can spread to the brain and cause life-threatening infections. In this literature review, the focus was placed on the relevant causative bacteria, surgical procedures, and correlated medical conditions revolving around brain abscesses following dental work. This paper is written from a neurological surgery perspective, using information collected from several case studies, case reviews, and other related published manuscripts. Several risk factors have been identified to predispose oral cavity bacterial infection to cause brain abscess: dental work done in the upper molars; right-to-left shunts in the heart; and poor dental hygiene. If the bacterium of the abscess is correctly identified, there is a greater effectiveness of treatment, but prolonging antibiotic and/or surgical treatment increases morbidity.

An examination of social and environmental determinants of secondhand smoke exposure among non-smoking adolescents.

INTRODUCTION: Adolescents are at increased risk of secondhand smoke exposure (SHS) due to the limited control that they have over social and physical environments. Yet, knowledge regarding determinants of SHS among non-smoking adolescents is limited. This study identifies social and environmental factors associated with SHS among non-smoking adolescents. METHODS: To be included, parents and adolescents (aged 11-17 years) of the Adolescents, Place, and Behavior Study had to have completed surveys between March 2019 and May 2020. Adolescents had to have not reported smoking within the past 30 days and provided a saliva sample assayed for cotinine (≤3 ng/mL). A series of stepwise linear regression models were fit to the data to identify social and environmental determinants of SHS, using log-transformed salivary cotinine. RESULTS: Of the 105 adolescent and parent dyads included, 90.3% were African American, 26.9% of parents reported smoking, 33.3% resided in multi-unit housing, and 67.7% lived in homes where smoking was not permitted. Significant associations were found between parent tobacco use (ß=2.56, SE=0.98, p=0.0082) and residing in multi-unit housing (ß=1.72, SE=0.86, p=0.0460) with increased log-transformed cotinine levels among non-smoking adolescents. Adolescent age, gender, and race/ ethnicity, parental education, peer tobacco use, the number of adults and children in the home, average number of days of self-reported SHS within public spaces outside of the home, and home smoking policies were not significantly associated with cotinine. CONCLUSIONS: Results emphasize the importance of reducing secondhand smoke exposure by reducing parental smoking and altering exposures within social and home environments. Parental tobacco use and residential setting should be considered when developing interventions to reduce secondhand smoke exposure among non-smoking adolescents.

Neurovascular Interactions in the Neurologically Compromised Neonatal Brain.

Neurological brain injuries such as hypoxic ischaemic encephalopathy (HIE) and associated conditions such as seizures have been associated with poor developmental outcome in neonates. Our limited knowledge of the neurological and cerebrovascular processes underlying seizures limits their diagnosis and timely treatment. Diffuse optical tomography (DOT) provides haemodynamic information in the form of changes in concentration of de/oxygenated haemoglobin, which can improve our understanding of seizures and the relationship between neural and vascular processes. Using simultaneous EEG-DOT, we observed distinct haemodynamic changes which are temporally correlated with electrographic seizures. Here, we present DOT-EEG data from two neonates clinically diagnosed as HIE. Our results highlight the wealth of mutually-informative data that can be obtained using DOT-EEG techniques to understand neurovascular coupling in HIE neonates.

Nutritional strategy for adolescents undergoing bariatric surgery: report of a working group of the Nutrition Committee of NASPGHAN/NACHRI.

Surgical options for the treatment of adolescent obesity have been gaining popularity. Adolescent patients present a particular challenge to clinicians, secondary to age-related issues, revolving around both mental and physical growth. These age-related issues require a unique approach to nutritional intervention for adolescents undergoing bariatric surgery as opposed to standardized approaches for adults. Despite the increasing numbers of adolescents undergoing obesity surgery, evidence-based nutritional guidelines have yet to be published. The goal of this document is to provide the clinician with recommendations on how to assess, educate, nourish, and monitor the adolescent who has undergone obesity surgery. A multidisciplinary panel composed of 3 pediatric gastroenterologists, 1 psychologist, and 3 registered dietitians from the Nutrition Committee for the North American Society of Pediatric Gastroenterology, Hepatology, and Nutrition and National Association of Children's Hospitals and Related Institutions, with experience in nutrition and adolescent weight loss surgery, reviewed the medical literature for evidence-based practice for nutritional strategies for patients undergoing bariatric surgery. In addition to this group, an adolescent medicine physician was consulted for matters related to reproductive health. The present article presents a consensus of recommendations based on a review of the literature. In areas for which there was a lack of evidence to support the recommendations, best-practice guidelines were used. The present article provides the clinician with an overview of the nutritional concerns for adolescent patients undergoing obesity surgery. These guidelines address the preoperative educational pathway, the postoperative diet progression, recognition of disordered eating, guidelines for female reproductive issues, and assistance for the adolescent in a school/college environment.

Transient haemodynamic events in neurologically compromised infants: a simultaneous EEG and diffuse optical imaging study.

We describe a series of novel simultaneous EEG and diffuse optical imaging studies of newborn infants. These experiments provide evidence of large, transient haemodynamic events which occur repeatedly and consistently within and across several infants with neurological damage, all of whom were diagnosed with seizures. A simple but independent process of rejecting artifacts and identifying events within diffuse optical imaging data is described, and this process is applied to data from 4 neurologically damaged neonates and from 19 healthy, age-matched controls. This method results in the consistent identification of events in three out of four of the neurologically damaged infant group which are dominated by a slow (>30s) and significant increase in oxyhaemoglobin concentration, followed by a rapid and significant decrease before a slow return to baseline. No comparable events are found in any of our control data sets. The importance and physiological implications of our findings are discussed, as is the suitability of a combined EEG and diffuse optical imaging approach to the study and monitoring of neonatal brain injury.

Accurate measurement of extracellular fluid volume from the slope/intercept technique after bolus injection of a filtration marker.

Extracellular fluid volume (ECV) is studied infrequently. The zero-time distribution volume (Vd) generated in the slope-intercept technique for measuring the glomerular filtration rate (GFR) substantially overestimates ECV. The aim was to validate a new technique for measuring ECV from the slope-intercept approach. GFR and ECV were measured using Cr-51-EDTA and iohexol injected into opposite arms in 51 patients undergoing routine measurement of GFR and on 48 occasions in 20 healthy volunteers. Blood samples were obtained bilaterally 20, 40, 60, 120, 180 and 240 min post-injection and assayed for indicator injected contralaterally. Reference ECV (ECV6) was calculated from all six samples as the product of indicator transit time and multi-sample GFR. GFR/ECV was calculated as the rate constant of the exponential fitted to the last three samples (GFR/ECV3). Slope-intercept GFR was calculated from the last three samples using the slope-intercept technique (GFR3). ECV (ECV3) was calculated by dividing GFR3 by GFR/ECV3, having corrected both for their one-compartment assumptions. ECV6(EDTA) correlated closely with ECV3(EDTA) (ECV3(EDTA) = 1.01.ECV6(EDTA)-0.5 L; r = 0.97; n = 99), but less closely with Vd (Vd = 1.17.ECV6(EDTA) + 0.7 L; r = 0.86). ECV6(iohexol) correlated slightly better with ECV6 (EDTA) (ECV6(EDTA) = 0.81.ECV6(iohexol) + 3.3 L; r = 0.86) than with ECV3(EDTA) (ECV3(EDTA) = 0.83.ECV6(iohexol) + 2.9 L; r = 0.84) and had slightly narrower 95% limits of agreement (-3.82 and 2.82 L versus -3.90 to 3.43 L). In conclusion, ECV can be measured from three samples almost as accurately as ECV from multiple samples.

Comparison of GFR measurements assessed from single versus multiple samples.

BACKGROUND: Many previous studies have evaluated single-sample glomerular filtration rate (GFR) against multisample GFR, of which the single sample was a member, but none have compared single and multisample GFRs against an independent reference method. We therefore performed this comparison by using simultaneous independent multisample GFR measured with a different indicator. SETTING & PARTICIPANTS: University hospital: patients and healthy volunteers (95 studies in 60 patients and 20 healthy participants). Healthy volunteers were studied fasting and after food; 10 of them had a repeated fasting study. STUDY DESIGN: Diagnostic test study. INDEX TEST: Single-sample GFR. REFERENCE TEST: Multisample GFR with a different indicator. MEASUREMENTS: GFR was measured by using chromium-51 ((51)Cr)-EDTA and iohexol, injected into opposite arms and scaled to 1.73 m(2). Blood samples, obtained bilaterally 20, 40, 60, 120, 180, and 240 minutes after injection, were assayed for indicator injected contralaterally. Single-sample GFR (Jacobsson method) was calculated from indicator concentrations at 3 and 4 hours. Single-sample GFR from 1 indicator was compared with multisample GFR from the other and vice versa, as well as from the same indicator. Differences were expressed as limits of agreement between paired measurements in Bland-Altman plots. Precision was expressed as the SD of the mean difference between paired measurements. RESULTS: Limits of agreement between multisample GFRs measured by using (51)Cr-EDTA and iohexol (-12 to 20 mL/min) were similar to the corresponding limits for single-sample GFR at 3 (-16 to 17 mL/min) and 4 hours (-11 to 17 mL/min). The precision of single-sample GFR at 4 hours by using (51)Cr-EDTA for predicting iohexol multisample GFR (6.9 mL/min) was better than that of multisample GFR with (51)Cr-EDTA (7.9 mL/min). When analysis was limited to patients with GFR less than 60 mL/min, single-sample GFR was slightly inferior to multisample GFR. In healthy participants, single-sample GFR with (51)Cr-EDTA at 3 and 4 hours showed repeatability (SD of change, 9.4 and 9.3 mL/min) similar to multisample GFR with (51)Cr-EDTA (10.7 mL/min). Single-sample GFR at 4 hours by using (51)Cr-EDTA detected a food-induced increase in GFR (4.4 +/- 5.9 mL/min; P < 0.001) with more confidence than multisample GFR by using (51)Cr-EDTA (4.6 +/- 7.5 mL/min; P < 0.01). LIMITATIONS: No separate gold standard (eg, inulin) to facilitate interpretation of observed differences between 2 markers. CONCLUSIONS: Single-sample GFR is as reliable as multisample GFR for measuring GFR, especially when GFR is greater than 60 mL/min.

Evaluation of the Modification of Diet in Renal Disease equation (eGFR) against simultaneous, dual-marker multi-sample measurements of glomerular filtration rate.

BACKGROUND: Estimation of glomerular filtration rate (GFR) using plasma creatinine remains controversial, especially when GFR approaches normal values. The aim was to re-examine estimated GFR (eGFR) using dual-reference GFR measurements. METHODS: eGFR (simplified modified Modification of Diet in Renal Disease equation) was compared with GFR measured with iohexol for predicting GFR measured with (51)Cr-ethylenediaminetetraacetic acid (EDTA). Dual six-sample GFR (20-240 min postinjection) was measured in 60 patients and 20 normal volunteers with (51)Cr-EDTA (GFR(EDTA)) and iohexol (GFR(iohexol)) injected into separate arms and sampled contralaterally. This was repeated in the normal volunteers under fasting conditions (twice in nine). Percentage bias, imprecision (SD of bias) and disagreement (sign-less difference) between eGFR and GFR(EDTA) were compared with those between GFR(iohexol) and GFR(EDTA). RESULTS: Changes between fasting and postprandial eGFR correlated significantly with corresponding changes in GFR(iohexol) and GFR(EDTA). eGFR predicted GFR(EDTA) less precisely (SD 19.9%) than GFR(iohexol) (10.5%; P < 0.01). Although eGFR showed a poorer correlation with GFR(EDTA) when GFR(EDTA) > 80 mL/min/1.73 m(2) compared with <80 mL/min/1.73 m(2), there was no significant difference with respect to imprecision or disagreement of >20 or 30%. However, eGFR was closer than GFR(iohexol) to GFR(EDTA) in a higher fraction of studies when GFR(EDTA) > 80 mL/min/1.73 m(2) (28/60) than when it was <80 mL/min/1.73 m(2) (9/37; P < 0.05). CONCLUSION: eGFR is inferior to GFR(iohexol) for predicting GFR(EDTA). The disagreement between GFR(iohexol) and GFR(EDTA) illustrates the extent to which uncertainty in GFR(EDTA) contributes to the performance of eGFR. eGFR performs no better at lower, compared with higher levels of GFR.

Using the slope-only technique and estimated glomerular filtration rate for checking the reliability of slope-intercept measurement of glomerular filtration rate.

AIM: To develop a strategy for checking the reliability of slope intercept measurement of glomerular filtration rate (GFR). METHODS: Six blood samples, obtained bilaterally 20-240 min after the injection of Cr-ethylenediaminetetraacetic acid (EDTA) and iohexol into opposite arms, were assayed for indicator injected contralaterally. GFR6iohexol, the reference value, was measured for all six samples and GFR3EDTA (slope-intercept) for the last three samples (per 1.73 m). GFR was measured from the half-time [GFR/extracellular fluid volume (ECV)3EDTA], for the single samples at 2-4 h (Christensen-Groth; GFR1) and for creatinine [estimated GFR (eGFR)]. RESULTS: In six of the 97 studies, the correlation coefficient (r) of the fit to the last three sample points was less than 0.99. In the remaining 91 studies, GFR3EDTA disagreed with GFR/ECVEDTA by more than 15% in 19 studies (group A) and by less than 15% in 72 studies (group B). GFR3EDTA disagreed with GFR6iohexol by 12.6% in group A but only by 6.3% in group B (P<0.001). No such discrimination was displayed by eGFR. Although GFR3EDTA was within 15%of GFR6iohexol in 14 group A studies, eGFR was within 15% of GFR3EDTA in only eight studies and disagreed by more than 15% in six studies. Conversely, in the five of the 19 studies in which GFR3EDTA disagreed with GFR6iohexol by more than 15%, the agreement between eGFR and GFR3EDTA was less than 15% in two studies and more than 15% in three studies. GFR3EDTA was within 15% of GFR/ECV3EDTA in all six studies in which r was less than 0.99, and GFR3EDTA disagreed with GFR6iohexol by less than 15%. Confidence in GFR3EDTA was not improved by GFR1 or eGFR. CONCLUSION: Slope intercept GFR is reliable if within 15% of GFR/ECV3. Estimated GFR was ineffective as a second checkpoint. GFR1 did not help when the fit was poor.

Suitability of a simplified technique based on iohexol for decentralized measurement of glomerular filtration rate.

OBJECTIVE: The aim of the study was to assess a simplified method for measuring glomerular filtration rate (GFR) using iohexol that could form the basis of a decentralized service for measuring GFR by sample transportation. MATERIAL AND METHODS: Non-fasting GFR was measured with Cr-51-EDTA and iohexol injected simultaneously into opposite arms (n = 110). Cubital venous blood samples, obtained bilaterally 20, 40, 60, 120, 180 and 240 min after injection, were assayed for marker injected contralaterally, Cr-51-EDTA by well-counting and iohexol by X-ray fluorescence. Following biexponential analysis of the clearance curves, GFR was measured from all six samples and also from the last three samples and scaled to body surface area (BSA). GFR scaled to extracellular fluid volume (GFR/ECV) was calculated from six samples as the mean transit time of marker through its distribution volume and from three samples as the clearance half-time. RESULTS: Cr-51-EDTA correlated closely with iohexol for measuring GFR/BSA (r = 0.97 for three samples, 0.94 for six). The two markers agreed more closely with each other in the measurement of GFR/BSA compared with GFR/ECV. GFR/BSA values showed better agreement with corresponding GFR/ECV values when they were measured with Cr-51-EDTA compared with iohexol. Six samples offered no significant advantage compared with three. CONCLUSIONS: Iohexol is less accurate than Cr-51-EDTA and scaling to BSA is more robust than scaling to ECV. Nevertheless, iohexol has potential to measure GFR by sample transportation, without having to measure injected dose. This would allow accurate measurement of GFR in a primary care setting.

Reliability of the MDRD method for estimating glomerular filtration rate in relation to gender, body mass index and extracellular fluid volume.

BACKGROUND: The accuracy of estimating glomerular filtration rate from plasma creatinine (eGFR) has been questioned but it is unclear how much covert error in several reference methods that have been used has contributed to this perceived inaccuracy. The aim of the study was to evaluate eGFR in comparison with a second 'gold standard' to test the performance of the primary gold standard and to examine the influence of patient demographics (age, body mass index (BMI), extracellular fluid volume (ECV) and gender). DESIGN: Non-fasting multisample GFR and ECV were measured in 80 subjects simultaneously and independently with Cr-51-EDTA (GFR(EDTA)) and iohexol (GFR(iohexol)). Percentage bias and imprecision in the prediction of, and disagreement with, GFR(EDTA) were compared between eGFR and GFR(iohexol). Another simplified method for measuring GFR, the slope-only method ((SO)GFR), was also evaluated against multisample GFR (measured with the opposing indicator). Accuracies were assessed in all subjects and across age, BMI and ECV boundaries of 65 y, 29 kg m(-2) and 14 L. RESULTS: eGFR was less precise than GFR(iohexol) (imprecisions of 22.3% and 12.9%; P < 0.01). The precision of (SO)GFR was intermediate between eGFR and GFR(iohexol). Both GFR(iohexol) and eGFR were less precise in the elderly, the obese and men, but minimally influenced by ECV. (SO)GFR was minimally influenced by subject demographics. CONCLUSION: Although eGFR does not predict GFR (based on a primary gold standard) as accurately as a second gold standard, a significant component of its poor performance is the result of inaccuracy in the primary gold standard. (SO)GFR measured with Cr-51-EDTA is superior to eGFR.