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1.
The European Journal of Health Economics - The aims of this study were to assess whether there is a conceptual overlap between the questionnaires HIT-6 and EQ-5D and to develop a mapping algorithm...  相似文献   
2.

Objective

Medical devices (MDs) encompass a broad and heterogeneous range of technologies. While practices vary considerably across countries, MDs often find application in patient care with little or no evaluation of their effectiveness and safety following market approval. A recently proposed taxonomy of MDs considered devices from the viewpoint of Health Technology Assessment (HTA). The aim of the work presented here was to test its plausibility and applicability by considering real-world HTA practices.

Methods

HTA reports on MDs from European institutions were collected in a systematic manner and the evaluated devices and/or related procedures were matched to a position on the taxonomy. Following this, representatives from 16 European HTA institutions were asked about the usefulness of the taxonomy in semi-structured interviews.

Results

1237 HTA reports (2004–2015) from 33 European institutions were included in the sample. The majority of reports was on technologies from the taxonomic positions initially estimated as having high relevance. Most of the experts interviewed stated that they found the taxonomy useful, particularly regarding its potential to aid in selecting technologies for assessment and to highlight potential methodological particularities per taxonomic position.

Conclusions

Overall, the distribution of identified reports on the matrix confirmed that the initial estimation of the relevance and necessity of HTA provided in the taxonomic model is plausible. In addition, interviews with representatives of European HTA institutions showed that the taxonomy could be useful.  相似文献   
3.
Abstract

Wharton’s Jelly (WJ) tissue is a promising biomaterial, for tissue engineering applications. However, its preservation over a long period in order to be readily available needs further optimization. A possible solution could be the vitrification and storage of WJ tissue at low temperatures. The aim of this study is to evaluate the effect of low temperature in the WJ tissue, which was stored at ?196?°C, either with the vitrification or conventional cryopreservation methods. WJ tissues were isolated from human umbilical cords, cryopreserved with the above methods and remained for 1?year at ?196?°C. Histological analysis of tissue’s extracellular matrix (ECM), isolation, and characterization of mesenchymal stromal cells (MSCs) were performed. Histological analysis revealed the presence of ECM components such as collagen, sulfated glycosaminoglycans (sGAGs), and the presence of cell nuclei only in vitrified samples. Furthermore, MSCs were isolated and expanded successfully from vitrified WJ tissues, whereas a few viable cells were obtained from conventionally cryopreserved tissues that were not further expanded. In conclusion, this study indicated the proper preservation of vitrified WJ tissues after 1?year of storage, which eventually could be used in tissue engineering and regenerative medicine approaches.  相似文献   
4.
How to cite this article: Papathanakos G, Andrianopoulos I, Papathanasiou A, Lepida D, Koulouras V. Adapting in the COVID-19 Era. Indian J Crit Care Med 2020;24(12):1286–1287.  相似文献   
5.
6.
ObjectivesElucidating critical aortic diameters at which natural complications (rupture, dissection, and death) occur is of paramount importance to guide timely surgical intervention. Natural history knowledge for descending thoracic and thoracoabdominal aortic aneurysms is sparse. Our small early studies recommended repairing descending thoracic and thoracoabdominal aortic aneurysms before a critical diameter of 7.0 cm. We focus exclusively on a large number of descending thoracic and thoracoabdominal aortic aneurysms followed over time, enabling a more detailed analysis with greater granularity across aortic sizes.MethodsAortic diameters and long-term complications of 907 patients with descending thoracic and thoracoabdominal aortic aneurysms were reviewed. Growth rates (instrumental variables approach), yearly complication rates, 5-year event-free survival (Kaplan–Meier), and risk of complications as a function of aortic height index (aortic diameter [centimeters]/height [meters]) (competing-risks regression) were calculated.ResultsEstimated mean growth rate of descending thoracic and thoracoabdominal aortic aneurysms was 0.19 cm/year, increasing with increasing aortic size. Median size at acute type B dissection was 4.1 cm. Some 80% of dissections occurred below 5 cm, whereas 93% of ruptures occurred above 5 cm. Descending thoracic and thoracoabdominal aortic aneurysm diameter 6 cm or greater was associated with a 19% yearly rate of rupture, dissection, or death. Five-year complication-free survival progressively decreased with increasing aortic height index. Hazard of complications showed a 6-fold increase at an aortic height index of 4.2 or greater compared with an aortic height index of 3.0 to 3.5 (P < .05). The probability of fatal complications (aortic rupture or death) increased sharply at 2 hinge points: 6.0 and 6.5 cm.ConclusionsAcute type B dissections occur frequently at small aortic sizes; thus, prophylactic size-based surgery may not afford a means for dissection protection. However, fatal complications increase dramatically at 6.0 cm, suggesting that preemptive intervention before that criterion can save lives.  相似文献   
7.
Previous studies have shown that in vitro exposure to single compounds released from composite resins may induce cell death. In the present study the effects of eluates from commercially available composite resins used for direct or indirect restorations were evaluated on the cell cycle progression and type of cell death of cultured WEHI 13 var fibroblasts. Cells exposed to eluates of the materials were assessed for cytotoxicity by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay for cell death, for cell cycle profiles by flow cytometry, for caspase-3 biochemically and by immunocytochemistry, and for morphological changes by fluorescence microscopy with acridine orange. The direct composite resin eluates induced extensive apoptosis, followed by secondary necrosis. This was accompanied by cell enlargement, micromultinucleation, chromatin disintegration, cell cycle arrest at different phases, and caspase-3 activation. The composites for indirect restorations were much less cytotoxic at all biological end-points investigated. The findings suggest that composite resins used for direct and indirect dental restorations differ in their cytotoxic potential and their ability to affect basic cellular functions. This underlines the impact of improved polymerization with respect to their biologic behavior.  相似文献   
8.

Introduction

Olfactory neuroblastomas are rare malignant tumors that usually occur in the upper nasal cavity. The purpose of this paper is to present a case of a large olfactory neuroblastoma filling the entire nasal cavity, treated with an Altemir technique modification.

Methods

A 39-year-old woman presented with a large tumor of the nasal cavity. After the laboratory examinations, the tumor was classified as a Kadish stage A olfactory neuroblastoma. The selected treatment was the surgical excision after an Altemir technique modification combined with midfacial degloving and additional radiotherapy.

Results

Histopathology revealed a Hyams grade III olfactory neuroblastoma completely removed. Although the patient refused the additional radiotherapy, 18 months postoperatively, there were no signs of recurrence, and the patient shows big improvement on her sense of smell.

Conclusions

Large olfactory neuroblastomas filling the entire nasal cavity extending back to the postnasal space can be completely removed using a transfacial approach as the Altemir technique modification is.  相似文献   
9.
BACKGROUND: Although herpes viruses have been implicated in the pathogenesis of chronic and aggressive periodontitis, few data in the literature refer to quantification of these viruses in periodontal sites, especially in relation to serological findings. OBJECTIVE: The aim of the present study was to compare Epstein--Barr virus (EBV) DNA load in subgingival specimens from chronic periodontitis patients and in periodontally healthy subjects, in relation to serologic testing of IgM and IgG antibodies to EBV. METHODS: A total of 22 chronic periodontitis patients and 13 controls participated in the present study. Seventy-nine subgingival specimens (one pooled, one from a deep and one from a shallow site), sampled with paper points, were analysed with real-time polymerase chain reaction for EBV. Subjects were also examined for anti-EBV IgG and IgM levels in serum, using an enzyme-linked immunosorbent assay. RESULTS: One subject was seronegative for EBV. Three subjects (one patient and two controls) displayed anti-EBV IgM. Their data were excluded from further analysis. All three displayed EBV in their subgingival samples. Nine out of the remaining 20 chronic periodontitis patients and 10 out of 11 controls did not display EBV subgingivally. A statistically significant difference in viral load was observed between pooled and shallow-pocket samples from periodontitis patients but not between samples from deep and shallow pockets (Kruskall--Wallis anova, Dunn's multiple comparisons test). CONCLUSIONS: Data from the present study do not strongly support the pathogenetic significance of EBV in chronic periodontitis lesions. The data do, however, suggest that parallel serological assessments provide a useful insight into the association of viruses with periodontal disease.  相似文献   
10.
Positron emission tomography (PET) targeting the 18 kDa translocator protein (TSPO) is used to quantify neuroinflammation. Translocator protein is expressed throughout the brain, and therefore a classical reference region approach cannot be used to estimate binding potential (BPND). Here, we used blockade of the TSPO radioligand [11C]PBR28 with the TSPO ligand XBD173, to determine the non-displaceable volume of distribution (VND), and hence estimate the BPND. A total of 26 healthy volunteers, 16 high-affinity binders (HABs) and 10 mixed affinity binders (MABs) underwent a [11C]PBR28 PET scan with arterial sampling. Six of the HABs received oral XBD173 (10 to 90 mg), 2 hours before a repeat scan. In XBD173-dosed subjects, VND was estimated via the occupancy plot. Values of BPND for all subjects were calculated using this VND estimate. Total volume of distribution (VT) of MABs (2.94±0.31) was lower than VT of HABs (4.33±0.29) (P<0.005). There was dose-dependent occupancy of TSPO by XBD173 (ED50=0.34±0.13 mg/kg). The occupancy plot provided a VND estimate of 1.98 (1.69, 2.26). Based on these VND estimates, BPND for HABs is approximately twice that of MABs, consistent with predictions from in vitro data. Our estimates of [11C]PBR28 VND and hence BPND in the healthy human brain are consistent with in vitro predictions. XBD173 blockade provides a practical means of estimating VND for TSPO targeting radioligands.  相似文献   
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