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131.
PurposeThe purpose of this study was for an international panel of experts to establish consensus indications for distal rectus femoris surgery in children with cerebral palsy (CP) using a modified Delphi method.MethodsThe panel used a five-level Likert scale to record agreement or disagreement with 33 statements regarding distal rectus femoris surgery. The panel responded to statements regarding general characteristics, clinical indications, computerized gait data, intraoperative techniques and outcome measures. Consensus was defined as at least 80% of responses being in the highest or lowest two of the five Likert ratings, and general agreement as 60% to 79% falling into the highest or lowest two ratings. There was no agreement if neither threshold was reached.ResultsConsensus or general agreement was reached for 17 of 33 statements (52%). There was general consensus that distal rectus femoris surgery is better for stiff knee gait than is proximal rectus femoris release. There was no consensus about whether the results of distal rectus femoris release were comparable to those following distal rectus femoris transfer. Gross Motor Function Classification System (GMFCS) level was an important factor for the panel, with the best outcomes expected in children functioning at GMFCS levels I and II. The panel also reached consensus that they do distal rectus femoris surgery less frequently than earlier in their careers, in large part reflecting the narrowing of indications for this surgery over the last decade.ConclusionThis study can help paediatric orthopaedic surgeons optimize decision-making for, and outcomes of, distal rectus femoris surgery in children with CP.Level of evidenceV  相似文献   
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The tumor immune microenvironment of oral tongue squamous cell carcinoma may be accountable for differences in clinical behavior, particularly between different age groups. We performed RNA expression profiling and evaluated tumor infiltrating lymphocytes (TILs) and their T-cell subsets in order to assess the functional status of oral tongue squamous cell carcinoma tumor microenvironment and detect potentially clinically useful associations. Archival surgical pathology material from sixteen oral tongue squamous cell carcinoma patients was microscopically evaluated for TIL densities. RNA was extracted from macrodissected whole tumor sections and normal controls and RNA expression profiling was performed by the NanoString PanCancer IO 360 Gene Expression Panel. Immunostains for CD4, CD8 and FOXP3 were evaluated manually and by digital image analysis. Oral tongue squamous cell carcinomas had increased TIL densities, numerically dominated by CD4 + T cells, followed by CD8 + and FOXP3 + T cells. RNA expression profiling of tumors versus normal controls showed tumor signature upregulation in inhibitory immune signaling (CTLA4, TIGIT and PD-L2), followed by inhibitory tumor mechanisms (IDO1, TGF-β, B7-H3 and PD-L1). Patients older than 44 years showed a tumor microenvironment with increased Tregs and CTLA4 expression. Immunohistochemically assessed CD8% correlated well with molecular signatures related to CD8 + cytotoxic T-cell functions. FOXP3% correlated significantly with CTLA4 upregulation. CTLA4 molecular signature could be predicted by FOXP3% assessed by immunohistochemistry (R2 = 0.619, p = 0.026). Oral tongue squamous cell carcinoma hosts a complex inhibitory immune microenvironment, partially reflected in immunohistochemically quantified CD8 + and FOXP3 + T-cell subsets. Immunohistochemistry can be a useful screening tool for detecting tumors with upregulated expression of the targetable molecule CTLA4.Electronic supplementary materialThe online version of this article (10.1007/s12105-020-01229-w) contains supplementary material, which is available to authorized users.  相似文献   
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European Journal of Epidemiology - Most studies of severe/fatal COVID-19 risk have used routine/hospitalisation data without detailed pre-morbid characterisation. Using the community-based UK...  相似文献   
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The quality of articular cartilage engineered using a cell-polymer construct depends, in part, on the chemical composition of the biomaterial and whether that biomaterial can support the chondrocytic phenotype. Acknowledging the supportive influence of tissue-specific matrix molecules on the chondrocytic phenotype, we have combined chondroitin sulfate-A (CSA) and chitosan, a glycosaminoglycan (GAG) analog, to develop a novel biomaterial to support chondrogenesis. Chitosan is a polycationic repeating monosaccharide of beta-1,4-linked glucosamine monomers with randomly located N-acetyl glucosamine units. Chitosan may be combined with the polyanionic CSA such that ionic crosslinking results in hydrogel formation. Bovine primary articular chondrocytes, when seeded onto a thin layer of CSA-chitosan, form discrete, focal adhesions to the material and maintain many characteristics of the differentiated chondrocytic phenotype, including round morphology, limited mitosis, collagen type II, and proteoglycan production. Our findings suggest CSA-chitosan may be well suited as a carrier material for the transplant of autologous chondrocytes or as a scaffold for the tissue engineering of cartilage-like tissue.  相似文献   
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The pharmacokinetics of recombinant human relaxin (rhRlx) after intravenous (iv) bolus administration and the absorption of rhRlx after intracervical or intravaginal administration were determined in nonpregnant women. The study was conducted in two parts. In part I, 25 women received 0.01 mg/kg rhRlx iv. After a minimum 7-day washout period, these women were dosed intracervically (n = 10) or intravaginally (n = 15) with 0.75 or 1.5 mg rhRlx, respectively, in 3% methylcellulose gel. Part II was a double-blind, randomized, three-way crossover study in 26 women. At 1-month intervals, each woman received one of three intravaginal treatments consisting of 0 (placebo), 1, or 6 mg rhRlx in 3% methylcellulose gel. The serum concentrations of relaxin following iv administration were described as the sum of three exponentials. The mean (±SD) initial, intermediate, and terminal half-lives were 0.09 ± 0.04, 0.72 ± 0.11, and 4.6 ± 1.2 hr, respectively. Most of the area under the curve was associated with the intermediate half-life. The weight-normalized clearance was 170 ± 50 mL/hr/kg. The observed peak concentration was 98 ± 29 ng/mL, and the weight-normalized initial volume of distribution was 78 ± 40 mL/kg, which is approximately equivalent to the serum volume. If central compartment elimination was assumed, the volume of distribution at steady state (V ss/W) was 280 ± 100 mL/kg, which is approximately equivalent to extracellular fluid volume. V ss/W could be as large as 1300 ± 400 mL/kg without this assumption. After intravaginal administration of the placebo gel, endogenous relaxin concentrations were evident (i.e., 20 pg/mL) in 9 of the 26 women (maximum concentrations, 23–234 pg/mL). A similar proportion of women (approximately 35–40%) exhibited measurable serum concentrations of relaxin following intravaginal rhRlx treatment; this proportion increased to 90% following intracervical rhRlx treatment. For both routes of administration, the maximum serum concentrations of relaxin were usually within the range of values observed for endogenous relaxin, suggesting that the absorption of rhRlx was minimal.  相似文献   
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