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71.

Background

Google Glass is a promising premarket device that includes an optical head-mounted display. Several proof of concept reports exist, but there is little scientific evidence regarding its use in a medical setting.

Objective

The objective of this study was to empirically determine the feasibility of deploying Glass in a forensics setting.

Methods

Glass was used in combination with a self-developed app that allowed for hands-free operation during autopsy and postmortem examinations of 4 decedents performed by 2 physicians. A digital single-lens reflex (DSLR) camera was used for image comparison. In addition, 6 forensic examiners (3 male, 3 female; age range 23-48 years, age mean 32.8 years, SD 9.6; mean work experience 6.2 years, SD 8.5) were asked to evaluate 159 images for image quality on a 5-point Likert scale, specifically color discrimination, brightness, sharpness, and their satisfaction with the acquired region of interest. Statistical evaluations were performed to determine how Glass compares with conventionally acquired digital images.

Results

All images received good (median 4) and very good ratings (median 5) for all 4 categories. Autopsy images taken by Glass (n=32) received significantly lower ratings than those acquired by DSLR camera (n=17) (region of interest: z=–5.154, P<.001; sharpness: z=–7.898, P<.001; color: z=–4.407, P<.001, brightness: z=–3.187, P=.001). For 110 images of postmortem examinations (Glass: n=54, DSLR camera: n=56), ratings for region of interest (z=–8.390, P<.001) and brightness (z=–540, P=.007) were significantly lower. For interrater reliability, intraclass correlation (ICC) values were good for autopsy (ICC=.723, 95% CI .667-.771, P<.001) and postmortem examination (ICC=.758, 95% CI .727-.787, P<.001). Postmortem examinations performed using Glass took 42.6 seconds longer than those done with the DSLR camera (z=–2.100, P=.04 using Wilcoxon signed rank test). The battery charge of Glass quickly decreased; an average 5.5% (SD 1.85) of its battery capacity was spent per postmortem examination (0.81% per minute or 0.79% per picture).

Conclusions

Glass was efficient for acquiring images for documentation in forensic medicine, but the image quality was inferior compared to a DSLR camera. Images taken with Glass received significantly lower ratings for all 4 categories in an autopsy setting and for region of interest and brightness in postmortem examination. The effort necessary for achieving the objectives was higher when using the device compared to the DSLR camera thus extending the postmortem examination duration. Its relative high power consumption and low battery capacity is also a disadvantage. At the current stage of development, Glass may be an adequate tool for education. For deployment in clinical care, issues such as hygiene, data protection, and privacy need to be addressed and are currently limiting chances for professional use.  相似文献   
72.
In the field of paediatric health care, measures based on consequences of health conditions have been recently developed to screen for children with special health care needs. These tools have been primarily used in survey research. The aim of this cross-sectional clinical study is to test the performance of a screener for identifying children with special health care needs (CSHCN) in a population of children with chronic conditions diagnosed and treated in different European paediatric hospitals. In the current study, the screener was employed in a sample of children with different chronic conditions (asthma, arthritis, dermatitis, epilepsy, cystic fibrosis, diabetes and cerebral palsy) across seven European countries; 456 parents of children, aged 4-7, 8-12, and 13-16 years, responded to the screener items. The study included a range of clinical measures to assess the severity of the conditions as well measures on functional health status. The prevalence of children identified positively with the CSHCN screener was 80%, which was higher than in survey estimates in the United States. Considerable variation in the screener classification was found between chronic conditions with cystic fibrosis and epilepsy showing higher rates, and skin conditions lower rates. There was no significant relationship between the screener classification and functional limitation. Findings of this study support in general the validity of the children with special health care needs screener, which shows, however, a differential validity across specific conditions. Several clinical and theoretical explanations for the lack of identifying some children with chronic conditions and the considerable variation between the conditions are discussed.Abbreviations CSHCN questionnaire for identifying children with special health care needs - FSII-(R) functional status II-(R) short form - QUICCC-R questionnaire for identifying children with special health care needs revised Funded by the European Commission, the DISABKIDS project is a cross-national effort to develop standardised instruments of health-related quality of life and needs in children and adolescents with chronic conditions. DISABKIDS international co-ordinator in chief: Monika Bullinger, Department of Medical Psychology, University Hospital of Hamburg, Martinistrasse 52, 20246 Hamburg, contract number: QLG-CT-2000-00716. Study centre: Silke Schmidt, Corinna Petersen; collaborating investigators: Hendrik Koopmann, Rolanda Baars, Department of Paediatrics, Leiden University Medical Centre, Netherlands; Peter Hoare, Hospital for Sick Children, University of Edinburgh, United Kingdom; Mick Power, Clare Atherton, Department of Psychiatry, University of Edinburgh, United Kingdom, Marie Claude Simeoni, Department of Public Health, University Hospital of Marseilles, France; John Tsanakas, Elpis Hatziagorou, Paraskevi Karagianni, University Paediatric Clinic, Athanasios Vidalis, Department of Psychiatry, Hippocratio Hospital, Thessaloniki, Greece, John Eric Chaplin, Department of Paediatrics, University Hospital Lund, Sweden; Michael Quittan, Rima Nourafza, Othmar Schuhfried, Department of Physical Medicine and Rehabilitation, University of Vienna, Austria; Ute Thyen, Esther Müller-Godeffroy, Department of Paediatrics, Medical University of Lübeck, Germany.  相似文献   
73.
Time‐of‐flight (TOF) MR angiography allows for noninvasive vessel imaging. To overcome the limited volumetric coverage of standard TOF techniques, the aim of this study was to investigate the combination of TOF and continuously moving table (CMT) acquisitions for peripheral vein imaging based on image subtraction. Two acquisition strategies are presented: a simple two‐step method based on 2‐fold CMT acquisition and an advanced one‐step method requiring only one continuous scan. Image quality of both CMT TOF techniques was evaluated by semiquantitative image grading and by signal‐to‐noise ratio and contrast‐to‐noise ratio analysis for veins of the upper and lower leg in 10 healthy volunteers. Results were compared to a standard stationary two‐dimensional (2D) TOF multistation acquisition. Image grading revealed good image quality for both CMT TOF methods, thereby confirming the feasibility of axial 2D CMT TOF to assess the veins of the lower extremities during a single scan. Quantitative evaluation showed no significant difference in signal‐to‐noise ratio and contrast‐to‐noise ratio compared to the stationary experiment. Additional measurements in three patients with postthrombotic changes and varicosities demonstrated the clinical applicability of the presented methods. CMT TOF provides promising results and permits the detection of various pathologic changes of the venous system. Magn Reson Med 63:1219–1229, 2010. © 2010 Wiley‐Liss, Inc.  相似文献   
74.
Endothelial selectins are crucial for the recruitment of leukocytes into sites of inflammation. On T cells, ligands for selectins become induced upon differentiation into the effector/memory stage. Initial in vitro studies suggested a correlation between the Th1 phenotype and ligand expression, but whether this also holds true in vivo remained uncertain. We here analyzed selectin ligands on CD4+ T cells producing IFN-gamma, IL-4 or IL-10, prototypic cytokines of the Th1, Th2 and Tr1 subset, respectively. We analyzed mice infected with influenza virus, the bacterium Listeria, and the parasites Toxoplasma (all Th1 models) or Nippostrongylus (Th2 model). A link between the Th1 phenotype and ligand expression was not found in vivo. Surprisingly, the potentially regulatory IL-10-producing T cells displayed the highest frequency of ligand-positive cells in general. Within the inflamed tissues, the frequencies of P-selectin-binding cells increased in the dominant subset, either Th1 or Th2. Up-regulation was also found for E-selectin ligands during influenza, but not Nippostrongylus infection. In conclusion, conditions driving T cell polarization into either Th1 or Th2 in vivo do not affect the expression of selectin ligands, but acquisition of P-selectin binding and hence migration into inflamed tissues is boosted by an inflammatory milieu.  相似文献   
75.
Abusive head trauma is a serious form of child abuse that can lead to severe neuropsychological sequelae or death in infants. In questionable cases, without a confession from the caregivers and ambiguous clinical information, evidence for the diagnosis of abusive head trauma is often based on typical patterns that have been observed in neuro-imaging. This study shows the progressive evolution of multifocal chronic subdural haematomas, including re-bleedings, in a case of abusive head trauma in an infant boy who was documented with repeated magnetic resonance imaging. The chronic subdural haematomas occurred during closely monitored in-patient rehabilitative care, and repeated maltreatment did not appear to be likely. Due to excessive growth, neurosurgical intervention with endoscopic craniotomy, evacuation of the subdural haematomas and temporal external cerebrospinal fluid drainage was performed with a favourable recovery. This study discusses the current pathophysiological knowledge concerning the development and clinical course of chronic subdural haematomas and draws relevant conclusions for the clinical practice and psychosocial management of caring for victims of abusive head trauma.  相似文献   
76.
N-Glycolylated (NeuGc) gangliosides are tumor-specific antigens and as such represent attractive targets for cancer immunotherapy. The chimeric antibody chP3 selectively recognizes a broad variety of NeuGc gangliosides, showing no cross-reactivity to the highly similar N-acetylated (NeuAc) gangliosides that are common cellular antigens in humans. Here, we report the crystal structure of the chP3 Fab and its computer-docking model with the trisaccharide NeuGcα3Galβ4Glcβ, which represents the carbohydrate moiety of the tumor-antigen NeuGc-GM3. The interaction involves only the heavy chain of the chP3 antibody. The modelled complex is consistent with all available experimental data and shows good surface complementarity. The negatively charged sialic acid residue NeuGc is buried in a pocket flanked by two arginine residues, VH Arg31 and VH Arg100A. We have further investigated the interaction of chP3 with its anti-idiotypic antibody, 1E10 (also known as Racotumomab), currently in clinical trials as a cancer vaccine. While many of the chP3 residues predicted to interact with the NeuGc ganglioside also feature prominently in the modelled complex of chP3 and 1E10, we do not observe structural mimicry. Rather, we suspect that the anti-idiotype 1E10 may serve as an imprint of the structural characteristics of the chP3 idiotype and, consequently, give rise to antibodies with P3-like properties upon immunization.  相似文献   
77.
The hepatocyte growth factor (HGF) has been crucially implicated in the development of proliferative retinal diseases; however, it is unclear whether retinal glial cells express or respond to HGF. Therefore, we examined the expression of HGF and of the receptor for HGF, c-Met, by immunohistochemical costaining with glial fibrillary acidic protein (GFAP) in epiretinal membranes of patients with proliferative vitreoretinopathy (PVR) and proliferative diabetic retinopathy (PDR), respectively. Furthermore, it was determined whether cells of the human retinal glial cell line, MIO-M1, secrete HGF protein, and whether HGF stimulates proliferation and chemotaxis, and secretion of the vascular endothelial growth factor (VEGF). Neuroretinas of patients with PVR express elevated mRNA level for HGF in comparison to control retinas. In epiretinal membranes of patients with PVR or PDR, immunoreactivity for HGF and for c-Met, respectively, partially colocalized with immunoreactivity for GFAP. Fetal bovine serum and basic fibroblast growth factor, but not heparin-binding epidermal or platelet-derived growth factors, evoked HGF secretion by cultured retinal glial cells. HGF displayed only a marginal effect on cell proliferation while it stimulated chemotaxis. HGF promoted the secretion of VEGF, via activation of the phosphatidylinositol-3 kinase. It is concluded that glial cells in epiretinal membranes express both HGF protein and c-Met receptors. The results suggest an autocrine/paracrine role of HGF in glial cell responses during proliferative vitreoretinal disorders as well as in retinal neovascularization, by stimulating of VEGF release.  相似文献   
78.
Biallelic loss‐of‐function mutations in SPG11 cause a wide spectrum of recessively inherited, neurodegenerative disorders including hereditary spastic paraplegia (HSP), amyotrophic lateral sclerosis, and Charcot‐Marie‐Tooth disease. By comprehensive screening of three large cohorts of HSP index patients, we identified 83 alleles with “small” mutations and 13 alleles that carry large genomic rearrangements. Including relevant data from previous studies, we estimate that copy number variants (CNVs) account for ~19% of pathogenic SPG11 alleles. The breakpoints for all novel and some previously reported CNVs were determined by long‐range PCR and sequencing. This revealed several Alu‐associated recombination hotspots. We also found evidence for additional mutational mechanisms, including for a two‐step event in which an Alu retrotransposition preceded the actual rearrangement. Apparently independent samples with identical breakpoints were analyzed by microsatellite PCRs. The resulting haplotypes suggested the existence of two rearrangement founder alleles. Our findings widen the spectra of mutations and mutational mechanisms in SPG11, underscore the pivotal role played by Alus, and are of high diagnostic relevance for a wide spectrum of clinical phenotypes including the most frequent form of recessive HSP.  相似文献   
79.
80.
Pyrazinamide (PZA) is a key antituberculosis drug, yet no rapid susceptibility test is commercially available. PZA drug susceptibility testing (DST) was performed directly on sputum samples from 327 patients and compared with the indirect method by using the Bactec MGIT 960 system in the context of patient screening for participation in a drug trial. Compared to standard indirect PZA DST, direct DST was successful in only 59% of cases, but results obtained were highly accurate and available faster. Agreement between the direct and indirect methods varied from 90 to 100% in each laboratory. The median times for obtaining PZA results from the time when the specimen was collected ranged from 11 to 16 days for the direct test and 18 to 95 days for the indirect test across laboratories. The direct method is accurate and reproducible across laboratories. It can be expected to accelerate results in >50% of cases, but it cannot replace indirect DST for PZA. Phenotypic methods remain the gold standard for DST in drug trials. If future studies can optimize the method to decrease the number of uninterpretable results, direct MGIT DST could be the new phenotypic DST standard for clinical trials, providing more rapid detection of resistance to new drugs in experimental regimens.  相似文献   
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