Social Media and Internet‐Based Data in Global Systems for Public Health Surveillance: A Systematic Review

Context: The exchange of health information on the Internet has been heralded as an opportunity to improve public health surveillance. In a field that has traditionally relied on an established system of mandatory and voluntary reporting of known infectious diseases by doctors and laboratories to governmental agencies, innovations in social media and so-called user-generated information could lead to faster recognition of cases of infectious disease. More direct access to such data could enable surveillance epidemiologists to detect potential public health threats such as rare, new diseases or early-level warnings for epidemics. But how useful are data from social media and the Internet, and what is the potential to enhance surveillance? The challenges of using these emerging surveillance systems for infectious disease epidemiology, including the specific resources needed, technical requirements, and acceptability to public health practitioners and policymakers, have wide-reaching implications for public health surveillance in the 21st century.Methods: This article divides public health surveillance into indicator-based surveillance and event-based surveillance and provides an overview of each. We did an exhaustive review of published articles indexed in the databases PubMed, Scopus, and Scirus between 1990 and 2011 covering contemporary event-based systems for infectious disease surveillance.Findings: Our literature review uncovered no event-based surveillance systems currently used in national surveillance programs. While much has been done to develop event-based surveillance, the existing systems have limitations. Accordingly, there is a need for further development of automated technologies that monitor health-related information on the Internet, especially to handle large amounts of data and to prevent information overload. The dissemination to health authorities of new information about health events is not always efficient and could be improved. No comprehensive evaluations show whether event-based surveillance systems have been integrated into actual epidemiological work during real-time health events.Conclusions: The acceptability of data from the Internet and social media as a regular part of public health surveillance programs varies and is related to a circular challenge: the willingness to integrate is rooted in a lack of effectiveness studies, yet such effectiveness can be proved only through a structured evaluation of integrated systems. Issues related to changing technical and social paradigms in both individual perceptions of and interactions with personal health data, as well as social media and other data from the Internet, must be further addressed before such information can be integrated into official surveillance systems.     

Left Ventricular Diastolic Dysfunction in Atrial Fibrillation: Predictors and Relation with Symptom Severity

Left Ventricular Diastolic Dysfunction in Atrial Fibrillation Background: Left ventricular diastolic dysfunction (LVDD) is common in the general population, but its prevalence in atrial fibrillation (AF), predictors for LVDD in AF and the association between LVDD and AF‐related symptom severity has not been well studied. Methods: In 124 consecutive patients (mean age 61 ± 11years, 60% male) with paroxysmal (n = 70) or persistent AF (n = 54) referred for AF catheter ablation, LVDD was evaluated according to current guidelines using transthoracic echocardiography. AF‐related symptom severity was quantified using the European Heart Rhythm Association score. Results: LVDD was present in 46 patients (37%). In uni‐ and multivariable regression analysis, age (OR 1.068 per year, 95% CI 1.023–1.115, P = 0.003) and persistent AF (OR 2.427 vs. paroxysmal AF, 95% CI 1.112–5.3, P = 0.026) were associated with LVDD. LVDD was found in 11% with mild AF symptoms (n = 27) as opposed to 44% in patients with moderate–severe AF symptoms (n = 97, P = 0.002). Thus, the OR for moderate–severe AF symptoms was 6.368 (1.797–22.568, P = 0.004) in the presence of LVDD. Conclusions: LVDD (1) occurs frequently in AF, (2) is associated with advancing age and AF progression and (3) is correlated with symptom severity in AF. (J Cardiovasc Electrophysiol, Vol. 23 pp. 1073‐1077, October 2012)     

E-SELECTIN EXPRESSION IN EXPERIMENTAL MODELS OF INFLAMMATION IN MICE

E-selectin (CD62E, formerly termed ELAM-1) is a cytokine-inducible adhesion molecule which mediates the binding of neutrophils, monocytes, and skin homing T-cells. The murine homologue of E-selectin has been cloned. A monoclonal antibody (21KC10) was used here to study immunohistochemically the expression and regulation of murine E-selectin in vitro and in vivo . As described for the human system, there was no staining of normal endothelium in skin and other tissues. LPS and tumour necrosis factor-alpha (TNF-α ), but not interleukin-4 (IL-4) or interferon-gamma (IFN- γ), induced a transient expression of E-selectin, both when injected in vivo and when added to endothelial cell lines in vitro. To analyse temporal expression of E-selectin under pathophysiological conditions in vivo, we chose two murine models of inflammation: allergic (ACD) and irritant contact dermatitis (ICD). Expression of E-selectin was found to be induced on vascular endothelium of post-capillary venules in both ACD and ICD. In ICD, maximal staining of endothelial cells occurred earlier than in ACD. Expression of E-selectin during ICD and ACD was then compared between strains of mice which differ with regard to the intensity of their inflammatory reaction. BALB/c mice, which in contrast to C57BI/6 mice show a denser infiltrate and prolonged influx of granulocytes and monocytes, revealed a more pronounced and more prolonged expression of E-selectin than C57BI/6 mice. This held true for both ACD and ICD, and in each case, peak expression of E-selectin was associated with the highest density of the leukocytic infiltrate. This study thus reveals regulatory mechanisms involved in the expression of murine E-selectin in vivo and in vitro . It also demonstrates a correlation between endothelial expression of E-selectin and the genetically determined intensity of the inflammatory response.     

Growth in Infancy and Childhood in Girls with Turner's Syndrome

ABSTRACT. We describe spontaneous longitudinal growth in girls with Turner's syndrome (TS), using the infancy-childhood-puberty (ICP) growth model. Lenght/height during the first 12 years of life was studied in 58 Swedish girls with TS. Their mean length at birth was 47.8 cm (SDS –1.4) and mean height at 12.0 years of age 127.3 cm (SDS –3.0). A clear age-dependent subnormality was observed in the change in length-height SDS (ΔSDS). Mean ΔSDS values at ages 0.0 to 0.5 and 3.0 to 6.0 years were normal. In contrast, the mean ΔSDS at ages 0.5 to 3.0 and 6.0 to 12.0 years were subnormal. The onset of the childhood growth component (normally located between 0.5 and 1.0 year of age) was, on the average, delayed by 0.28 year. This accounts for the subnormality of ΔSDS at 0.5 to 3.0 years of age. About 50% of the variation in height at 12.0 years of age, as determined by a multiple linear regression analysis, was significantly explained by length at 0.5 year of age, age at the onset of the childhood component, and ΔSDS at 6.0 to 12.0 years of age.     

Improved Growth Response to GH Treatment in Irradiated Children

ABSTRACT. The growth response to two years of GH treatment was studied in fifteen children after radiotherapy for a cranial tumor. The growth response was compared to that of short children (– 2 SD) and that of children with idiopathic growth hormone deficiency (GHD) of similar ages. All children were treated with hGH 0.1 IU/kg/day s.c; which is a higher dose and frequency than previously reported for irradiated children. On this protocol the growth rate increased 5.0 ± 0.5 cm/y (mean ± SEM) the first year and 3.8 ± 0.7 cm/y the second year compared to the growth rate the year before GH-treatment. Although the net gain in growth was higher than previously reported, the first year growth response was significantly reduced ( p < 0.05) compared to that of GHD-children (7.6 ± 0.5 cm/y) but exceeded ( p < 0.05) that of short children (3.4 ± 0.3 cm/y). The median spontaneous 24 h-GH secretion was 209 mU/I in the short children, 52 mU/I in the irradiated children and 16 mU/1 in the idiopathic GHD children. Thus the growth increment varied inversely to the spontaneous GH secretion observed in the three groups.     

Growth Hormone Treatment in Short Children -Short-Term and Long-Term Effects on Growth

Short children with normal GH responses to arginine-insulin provocation testing and various amounts of spontaneously secreted GH over 24 hours participated in an ongoing study with GH, 0.1 IU/kg/day. A total of 40 prepubertal children have been treated for 1 year. Their mean height velocity increased from 4.6 to 7.5 cm/year. The children with the slowest pretreatment height velocity showed the best increment. An inverse relationship was found between the endogenous GH secretion and the increment in growth; 80% of the children had an endogenous GH secretion of less than 300 milliunits/litre/24 hours, estimated as area under the curve above the calculated baseline. They all showed an increment in height above 2 cm. The remaining 20% all had an endogenous GH secretion of more than 300 milliunits/litre/24 hours, estimated as area under the curve above the calculated baseline, Twenty-four of the children were prepubertal for the following 4 years, and their GH therapy continued. Their Deight velocity changed from 4.2 cm/year before therapy to 8.1,6.7,6.0 and 4.9 cm/year for the 1st, 2nd, 3rd and 4th years on treatment. Many of them have passed their expected final height, but have still not stopped growing. Those children who were in early puberty when GH treatment started went into a rapid growth spurt and have now stopped growing. They have all reached but not improved their expected final height. In 15 of the children GH treatment was stopped after 1-3 years. Their mean height velocity for the first post-treatment year was 5.1 cm/year; thus, for the group as a whole no'catch down'was observed. Of the 15 children, only 4 decreased in height velocity despite increasing age. Further studies on the long-term results of GH treatment in larger groups of short children are needed to verify the findings in this study.     

A Longitudinal Study on Growth and Spontaneous Growth Hormone (GH) Secretion in Children with Irradiated Brain Tumors

ABSTRACT. Longitudinal growth was studied in 27 children after radiotherapy for a brain tumor. Growth deviation (1 SD) was found in 56% of the children after 2 years and was most profound in prepubertal children aged between 3 and 8 years at the time of irradiation. In this group growth velocity was markedly reduced and no catch up was seen. In all children studied growth hormone (GH) secretion, measured as the spontaneous secretion over 24 hours, was found to be severely disturbed. Our conclusion is that all children with a growth deviation 1 SD after radiotherapy (40 Gy) to the hypothalamo–hypophyseal region should be considered GH deficient. In such children GH treatment can be initiated without further testing.     

Accuracy at radiography and probing for the diagnosis of proximal caries

In 63 teenagers the proximal surfaces of premolars to be extracted for orthodontic reasons and the adjacent surfaces of neighboring teeth, 598 surfaces in all, were examined radiographically and by probing. Direct inspection after extraction revealed that 51% of the surfaces had incipient carious lesions and 5% lesions with cavities. Of the surfaces with cavities 82.1% were correctly diagnosed radiographically if any radiolucency, regardless of its extent, was used as a diagnostic criterion. However, this yielded a false positive rate of 19.6%. If only radioluccncies extending at least into the inner third of the enamel were called positive the true positive rate was 36.7% and the associated false positive rate 1.6%. At a 5% cavity frequency the predictive positive values were 17% and 53%, respectively. Probing yielded a true positive rate of about 29% and a false positive rate of 1.1% with a predictive positive value of 50-57%. All radiolucencies extending into the dentin were associated with cavities. When the most liberal radiographic criterion was used 37.5% of all carious lesions, whether associated with a cavity or not, were detected and 3.8% of sound surfaces were falsely called carious. The corresponding predictive positive value at the actual rate of incipient lesions and lesions with cavities was 92.6%.