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981.
982.

Background

Scoliosis is a three dimensional deformity, and brace correction should be 3D too. There is a lack of knowledge of the effect of braces, particularly in the sagittal and transverse plane. The aim of this study is to analyse the Sforzesco Brace correction, through all the parameters provided by Eos 3D imaging system.

Method

Design: This is a cross sectional study from a prospective database started in March 2003.Participants: 16 AIS girls (mean age 14.01) in Sforzesco brace treatment, with EOS x-rays, at start, in brace after 1 month and out of brace after the first 4 months of treatment. Outcome measures: All the parameters and the Torsio-Index obtained from 3D Eos System, in and out of brace, in the three planes. Statistical analysis: the variability of the parameters and the mean differences were analyzed and compared using paired T test. ANOVA was used for multiple comparisons. Critical P value was set at 0.05.

Results

In the comparison of in-brace vs start of treatment, the mean Cobb angle changed significantly from 36.44 +/? 4 to 28.99?+??3.9° (p?=?0.01). Significant changes in all the sagittal parameters were found (p?=?0.02). In the axial plane, the Torsio Index changed significantly in-brace for thoracolumbar and lumbar curves (P?<?0.05). The analysis of the single vertebral tilt demonstrated that the effect of the brace is mostly concentrated at specific segments: T4-T5, T10-T12, L1 and L5 in the axial plane and T3-T6 and T10-L1 in the frontal plane.

Conclusion

The Sforzesco brace mostly modifies the middle of the spine and preserves the sagittal balance. The single vertebral orientation in each plane should be considered together with the typically used values to assess brace effect.
  相似文献   
983.
984.

Introduction

Bio-repositories are invaluable resources to implement translational cancer research and clinical programs. They represent one of the most powerful tools for biomolecular studies of clinically annotated cohorts, but high quality samples are required to generate reliable molecular readouts and functional studies. The objective of our study was to define the impact of cancer tissue ischemia time on RNA and DNA quality, and for the generation of Patient-Derived Xenografts (PDXs).

Methods

One-hundred thirty-five lung cancer specimens were selected among our Institutional BioBank samples. Associations between different warm (surgical) and cold (ex-vivo) ischemia time ranges and RNA quality or PDXs engraftment rates were assessed. RNA quality was determined by RNA integrity number (RINs) values. Fresh viable tissue fragments were implanted subcutaneously in NSG mice and serially transplanted.

Results

RNAs with a RIN>7 were detected in 51% of the sample (70/135), with values of RIN significantly lower (OR 0.08, P = 0.01) in samples preserved for more than 3 hours before cryopreservation. Higher quality DNA samples had a concomitant high RIN. Sixty-three primary tumors (41 adenocarcinoma) were implanted with an overall engraftment rate of 33%. Both prolonged warm (>2 hours) and ex-vivo ischemia time (>10 hours) were associated to a lower engraftment rate (OR 0.09 P = 0.01 and OR 0.04 P = 0.008, respectively).

Conclusion

RNA quality and PDXs engraftment rate were adversely affected by prolonged ischemia times. Proper tissue collection and processing reduce failure rate. Overall, NSCLC BioBanking represents an innovative modality, which can be successfully executed in routine clinical settings, when stringent Standard Operating Procedures are adopted.  相似文献   
985.
Erythrocytes obtained from human patients with circulatory shock of different aetiology consistently showed a strong increase in lipid peroxidation-derived aldehydes in comparison with red cells of normal adults. The highly toxic compound 4-hydroxynonenal has been recovered exclusively in the erythrocytes of the patients.  相似文献   
986.
987.
988.
989.
Follicular 19 S thyroglobulin (molecular weight 660,000) from rat, human, and bovine thyroid tissues contains approximately 10-12 mol of phosphate/mol of protein. These phosphate residues can be radiolabeled when rat thyroid hemilobes, FRTL-5 rat thyroid cells, or bovine thyroid slices are incubated in vitro with [32P]phosphate. Thus labeled, the [32P]phosphate residues comigrate with unlabeled 19 S follicular thyroglobulin on sucrose gradients and gel filtration columns; are specifically immunoprecipitated by an antibody preparation to rat or bovine thyroglobulin as appropriate; and co-migrate with authentic 19 S thyroglobulin when subjected to analytic or preparative gel electrophoresis. Tunicamycin prevents approximately 50% of the phosphate from being incorporated into FRTL-5 cell thyroglobulin. Approximately one-half of the phosphate in FRTL-5 cell or bovine thyroglobulin can also be released by enzymatic deglycosylation and can be located in Pronase-digested peptides which contain mannose, are endo-beta-N-acetylglucosaminidase H but not neuraminidase-sensitive, and release a dually labeled oligosaccharide containing mannose and phosphate after endo-beta-N-acetylglucosaminidase H digestion. The remainder of the phosphate is in alkali-sensitive phosphoserine residues (3-4/mol of protein) and phosphotyrosine residues (approximately 2/mol of protein). This is evidenced by electrophoresis of acid hydrolysates of 32P-labeled thyroglobulin and by reactivity with antibodies directed against phosphotyrosine residues. The phosphoserine and phosphotyrosine residues do not appear to be randomly located through the thyroglobulin molecule since approximately 75-85% of the phosphotyrosine and phosphoserine residues were recovered in a approximately 15-kDa tryptic peptide or a approximately 24-kDa cyanogen bromide peptide, each almost devoid of carbohydrate. 31P nuclear magnetic resonance studies of bovine thyroglobulin confirm the presence and heterogeneity of the phosphate residues on thyroglobulin preparations.  相似文献   
990.
A novel glucosyltransferase which catalyzed the transfer of glucose from UDP-glucose to positions 2′ and 5′ of partially methylated flavonols was isolated from the shoots of Chrysosplenium americanum Schwein ex Hooker. It was purified 225-fold by ammonium sulfate precipitation and successive chromatography on Sephadex G-100, hydroxyapatite, and polybuffer ion exchanger. This glucosyltransferase appeared to be a single polypeptide with an apparent molecular weight of 42,000 daltons, pH optimum of 7.5 to 8.0, and an isoelectric point of 5.1. It had low but similar Km values for the 2′ and 5′ positions of flavonol substrates and the cosubstrate UDP-glucose and was inhibited by both reaction products, the glucosides formed, and UDP.

Glucosyltransferase activity was independent of divalent cations, was not inhibited by EDTA, but showed requirement for SH groups. The differential effect on enzyme activity of metal ions, especially cupric ion, and various SH group reagents seemed to indicate the involvement of two active sites in the glucosylation reaction; the site specific for 2′ activity being more susceptible than that of the 5′ activity. The substrate specificity expressed by this glucosyltransferase and the requirement of at least two para-oriented B-ring substituents (at 2′ and 5′) for activity support this view.

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