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RABBIA, FRANCO, BERNARD SILKE, ANDREA CONTERNO, TIZIANA GROSSO, BARBARA DE VITO, IVANA RABBONE, LIVIO CHIANDUSSI, AND FRANCO VEGLIO. Assessment of cardiac autonomic modulation during adolescent obesity. Obes Res. 2003; 11:541-548. Objective: To investigate the cardiovascular autonomic function in pediatric obesity of different duration by using standard time domain, spectral heart rate variability (HRV), and nonlinear methods. Research Methods and Procedures: Fifty obese children (13.9 Ϯ 1.7 years) were compared with 12 lean subjects (12.9 Ϯ 1.6 years). Obese children were classified as recent obese (ROB) (Ͻ4 years), intermediate obese (IOB) (4 to 7 years), and long-term obese (OB) (Ͼ7 years). In all participants, we performed blood pressure (BP) measurements, laboratory tests, and 24-hour electrocardiogram/ambulatory BP monitoring. The spectral power was quantified in total power, very low-frequency (LF) power, high-frequency (HF) power, and LF to HF ratio. Total, long-term, and short-term time domain HRV were calculated. Poincaré plot and quadrant methods were used as nonlinear techniques. Results: All obese groups had higher casual and ambulatory BP and higher glucose, homeostasis model assessment, and triglyceride levels. All parameters reflecting parasympathetic tone (HF band, root mean square successive difference, proportion of successive normal-to-normal intervals, and scatterplot width) were significantly and persistently reduced in all obese groups in comparison with lean controls. LF normalized units, LF/HF, and cardiac acceleration (reflecting sympathetic activation) were significantly increased in the ROB group. In IOB and OB groups, LF, but not nonlinear, measures were similar to lean controls, suggesting biphasic behavior of sympathetic tone, whereas nonlinear analysis showed a decreasing trend with the duration of obesity. Long-term HRV measures were significantly reduced in ROB and IOB. Discussion: Autonomic nervous system changes in adolescent obesity seem to be related to its duration. Nonlinear methods of scatterplot and quadrant analysis permit assessment of autonomic balance, despite measuring different aspects of HRV.

Objective Accurate diagnostic testing to identify SARS–CoV-2 infection is critical. Although highly specific, SARS–CoV-2 reverse transcription polymerase chain reaction (RT-PCR), has shown, in clinical practice, to be affected by a non-insignificant proportion of false negative results. The study sought to explore whether the integration of lung ultrasound (LUS) with clinical evaluation is associated with increased sensitivity for the diagnosis of COVID-19 pneumonia, and therefore may facilitate the identification of false negative SARS-CoV-2 RT-PCR results. Methods This prospective cohort study enrolled consecutive adult patients with symptoms potentially related to SARS-CoV-2 infection admitted to the emergency department (ED) of an Italian academic hospital. Immediately after the initial assessment, a LUS evaluation was performed and the likelihood SARS-CoV-2 infection, based on both clinical and LUS findings (“integrated” assessment), was recorded. RT-PCR SARS-CoV-2 detection was subsequently performed. Results We enrolled 228 patients; 107 patients (46.9%) had SARS-CoV-2 infection. Sensitivity and negative predictive value of the clinical-LUS integrated assessment were higher than first RT-PCR [94.4% (95% CI 88.2-97.9), vs. 80.4% (95% CI 71.6-87.4); 95% (95% CI 89.5-98.2), vs. 85.2% (95% CI 78.3-90.6)]. Among the 142 patients who initially had negative RT-PCR, 21 resulted positive at a subsequent molecular test performed within 72 hours. All these false negative cases were correctly identified by the integrated assessment. Conclusion This study suggests that, in patients presenting to the ED with symptoms commonly associated with SARS-CoV-2 infection, the integration of LUS with clinical evaluation has high sensitivity and specificity for COVID-19 pneumonia and it may help to identify false negative results occurring with RT-PCR.

The aim of this study was to evaluate the distribution of resting heart rate and its biological and environmental determinants in adolescents. The study was crosssectional and the population consisted of 2230 children and adolescents, age range 12-18 years, enrolled randomly from state schools in Turin, Italy. In all participants the following parameters were evaluated: heart rate, blood pressure (BP), weight, height, degree of sexual development, physical activity, parental socio-cultural level. Heart rate and BP were measured after 5, 10 and 15 min in a sitting position. Furthermore, to obtain regression equations to define heart rate as a function of the other variables available, a multiple regression analysis was performed. In both sexes BP, but not heart rate, declined significantly from the first to the last

Abstract-We investigated the expression of ␣ 1 -adrenergic receptor subtypes in intact human peripheral blood lymphocytes using reverse transcription-polymerase chain reaction (RT-PCR) and radioligand binding assay techniques combined with antibodies against the three subtypes of ␣ 1 -adrenergic receptors (␣ 1A , ␣ 1B , and ␣ 1D 3 H]prazosin binding to a different extent. This indicates that human peripheral blood lymphocytes express the three ␣ 1 -adrenergic receptor subtypes. Of the three different ␣ 1 -adrenergic receptor subtypes, the ␣ 1B is the most represented and the ␣ 1D , the least. Future studies should clarify the functional relevance of ␣ 1 -adrenergic receptors expressed by peripheral blood lymphocytes. The identification of these sites may represent a step for evaluating whether they represent a marker of ␣ 1 -adrenergic receptors in cardiovascular disorders or for assessing responses to drug treatment on these receptors. (Hypertension. 1999;33:708-712.) Key Words: lymphocytes Ⅲ receptors, adrenergic, alpha Ⅲ receptor subtypes Ⅲ receptor antibodies I n the past few years, ␣-and ␤-adrenergic receptors have been demonstrated in peripheral blood lymphocytes with the use of radioligand binding assay techniques. The majority of information is available on ␤-adrenergic receptors, which were investigated primarily in essential hypertension, impaired left ventricular function, and acute stress. 1-5 Data on the expression of ␣-adrenergic receptors in peripheral blood lymphocytes are less extensive, with the ␣ 2 -receptor subtype being the most extensively investigated. 6,7 Some studies on the ␣ 1 -adrenergic receptor have not found its expression in human peripheral blood lymphocytes 8,9 and some studies have. 10 ␣ 1 -Adrenergic receptors mediate some cardiovascular sympathetic responses, such as arteriolar smooth muscle constriction 11 and cardiac contractility, 12 and are involved in a variety of cardiovascular disorders, including hypertension, heart failure, and cardiac hypertrophy. 13 ␣ 1 -Adrenergic receptors represent a class of heterogeneous receptors. 14 Cloning studies have identified three distinct ␣ 1 -adrenergic receptor subtypes, named ␣ 1a -, ␣ 1b -, and ␣ 1d -adrenergic receptors. 14 -17 At present, ␣ 1 -adrenergic receptor subtypes are defined as ␣ 1A (␣ 1a ), ␣ 1B (␣ 1b ), and ␣ 1D (␣ 1d ), with uppercase and lowercase subscripts being used to designate native or recombinant receptor, respectively. 14,18 In view of the difficulty of investigating ␣ 1 -adrenergic receptors in vivo or in vitro using human samples of cardiovascular system, circulating blood cells may represent a model for the study of the cardiovascular ␣ 1 -adrenergic receptor system.In this article we have characterized ␣ 1 -adrenergic receptor subtypes expressed by human peripheral blood lymphocytes by reverse transcription-polymerase chain reaction (RT-PCR) to detect mRNA expression and by radioligand binding assay techniques combined with antibodies against different subtypes of ␣ 1 -adrenergic receptors. Methods Subjec...