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251.
Population‐based assessment of cancer‐specific mortality after local tumour ablation or observation for kidney cancer: a competing risks analysis
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252.
253.
Matthias Augustin Katharina Herberger Knut Kroeger Karl C. Muenter Lisa Goepel Reinhard Rychlik 《International wound journal》2016,13(1):82-87
Although chronic wounds have a high socio‐economic impact, data on comparative effectiveness of treatments are rare. UrgoStart® is a hydroactive dressing containing a nano‐oligosaccharide factor (NOSF). This study aimed at evaluating the cost‐effectiveness of this NOSF‐containing wound dressing in vascular leg ulcers compared with a similar neutral foam dressing (UrgoCell® Contact) without NOSF. Cost‐effectiveness analysis from the perspective of the German statutory health care system was performed using a decision tree model for a period of 8 weeks. Cost and outcome data were derived from the clinical study ‘Challenge’ suggesting a response rate (≥40% wound size reduction) of UrgoStart® of 65·6% versus 39·4% for the comparator. In the treatment model, effect‐adjusted costs of €849·86 were generated after 8 weeks for treatment with UrgoStart® versus €1335·51 for the comparator resulting in an effect‐adjusted cost advantage of €485·64 for UrgoStart®. In linear sensitivity analyses, the outcomes were stable for varying assumptions on prices and response rates. In an 8‐week period of treatment for vascular leg ulcers, UrgoStart® shows superior cost‐effectiveness when compared with the similar neutral foam dressing without any active component (NOSF). As demonstrated within a randomised, double‐blind clinical trial, UrgoStart® is also more effective in wound area reduction than the neutral foam dressing. Wound healing was not addressed in this clinical trial. Follow‐up data of 12 months to allow for reulceration assessment were not generated. 相似文献
254.
Dusan Hirjak Robert C. Wolf Katharina M. Kubera Bram Stieltjes Philipp A. Thomann 《Brain structure & function》2016,221(3):1209-1221
Minor motor and sensory deficits or neurological soft signs (NSS) are frequently found in patients with schizophrenia at any stage of their illness. Although previous studies have reported that NSS are associated with altered structure and function within fronto-parietal areas, it remains unclear whether the neuroanatomical basis of NSS may be confounded by underlying pathological processes, and by antipsychotic treatment. Morphological brain correlates of NSS in healthy subjects have seldom been investigated. This study evaluated the relationship between NSS levels and abnormalities of subcortical and cortical structures in healthy individuals. High-resolution MRI data at 3 Tesla were obtained from 68 healthy individuals. Automated segmentation of caudate nucleus, putamen, globus pallidus, thalamus, and brainstem was performed using both FSL-FIRST and Freesurfer. The surface-based analysis via Freesurfer enabled calculation of cortical thickness, area and folding (local gyrification index). NSS were examined on the Heidelberg Scale and related to both subcortical and cortical measurements. Using two fully automated brain segmentations methods, we found no significant association between NSS levels and morphological changes in subcortical structures. Higher NSS scores were associated with morphological changes of cortical thickness, area and folding in multiple areas comprising superior frontal, middle temporal, insular and postcentral regions. Our findings demonstrate the benefit of surface-based approaches when investigating brain correlates of NSS. The data lend further support to the hypothesis that NSS in healthy individuals involve multiple cortical rather than subcortical brain regions. 相似文献
255.
Neudorfer J Schmidt B Huster KM Anderl F Schiemann M Holzapfel G Schmidt T Germeroth L Wagner H Peschel C Busch DH Bernhard H 《Journal of immunological methods》2007,320(1-2):119-131
The development of MHC/peptide multimers has facilitated the visualization and purification of antigen-specific T cells. However, the persistence of multimers leads to prolonged T cell receptor signaling and subsequently to altered T-cell function. We have recently developed a new type of MHC/peptide multimers, which can be dissociated from the T cell. Herein, we have generated and tested for the first time reversible HLA/peptide multimers, termed Streptamers, for the isolation of human T cells. The Streptamer technique demonstrates the specificity and sensitivity of conventional HLA/peptide tetramers with regards to the sorting of human T lymphocytes. This is shown for T cells directed against immunogenic peptides derived from viral and tumor-associated antigens. We show that antigen-specific cytotoxic T cells remain functionally active following Streptamer dissociation, whereas lytic function and proliferation of the T cells is impaired in the presence of conventional tetramers. These novel HLA/peptide Streptamer reagents allow the isolation of antigen-specific T cells with preserved function and, therefore, facilitate the development of adoptive T cell transfer regimens for the treatment of patients with cancer or infectious diseases. 相似文献
256.
Kuhla B Boeck K Schmidt A Ogunlade V Arendt T Münch G Lüth HJ 《Neurobiology of aging》2007,28(1):29-41
The reaction of lysine and arginine residues of proteins with 1,2-dicarbonyl compounds result in the formation of advanced glycation end products (AGEs). Accumulation of AGEs is a characteristic feature of the aging brain and contributes to the development of neurodegenerative diseases such as Alzheimer's disease (AD). Therefore, it is of particular interest to study the cellular defense mechanisms against AGE formation and particularly the detoxification of their precursors. AGE precursor compounds such as methylglyoxal and glyoxal were cellulary detoxified by the glyoxalase system, consisting of glyoxalases I and II. Glyoxalase I levels are diminished in old aged brains but elevated in AD brains. However, it is still unknown how glyoxalase I level of AD brains changes in a disease and in an age-dependent manner. Therefore, we investigated the AD stage- and the age-dependent levels of glyoxalase I in the Brodmann area 22 of AD brains (n=25) and healthy controls (n=10). Our results obtained from RT-PCR reveal reducing glyoxalase I RNA levels with advancing stage of AD and with increasing age. Western Blot analysis indicates that in comparison to healthy controls, glyoxalase I protein amounts are 1.5-fold increased in early AD subjects and continuously decrease in middle and late stages of AD. The glyoxalase I protein amounts of AD patients also decrease with age. Results obtained from glyoxalase I activity measurement show 1.05-1.2-fold diminished levels in AD brains compared to healthy controls and no significant decrease neither with the stage of AD nor with age. The immunohistochemical investigations demonstrate an elevated number of glyoxalase I stained neurons in brains of early and middle but not in late AD subjects compared to age-matched healthy controls. In addition, the stage-dependent immunohistochemical investigation demonstrates that with reduced glyoxalase I staining AGE deposits prevail, specifically in late stage of AD. In conclusion, the decrease of glyoxalase I expression with increasing AD stage might be one reason for methylglyoxal-induced neuronal impairment, apoptosis, and AGE formation in plaques and tangles. 相似文献
257.
Determining human immunodeficiency virus coreceptor use in a clinical setting: degree of correlation between two phenotypic assays and a bioinformatic model
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Skrabal K Low AJ Dong W Sing T Cheung PK Mammano F Harrigan PR 《Journal of clinical microbiology》2007,45(2):279-284
Two recombinant phenotypic assays for human immunodeficiency virus (HIV) coreceptor usage and an HIV envelope genotypic predictor were employed on a set of clinically derived HIV type 1 (HIV-1) samples in order to evaluate the concordance between measures. Previously genotyped HIV-1 samples derived from antiretroviral-na?ve individuals were tested for coreceptor usage using two independent phenotyping methods. Phenotypes were determined by validated recombinant assays that incorporate either an approximately 2,500-bp ("Trofile" assay) or an approximately 900-bp (TRT assay) fragment of the HIV envelope gp120. Population-based HIV envelope V3 loop sequences ( approximately 105 bp) were derived by automated sequence analysis. Genotypic coreceptor predictions were performed using a support vector machine model trained on a separate genotype-Trofile phenotype data set. HIV coreceptor usage was obtained from both phenotypic assays for 74 samples, with an overall 85.1% concordance. There was no evidence of a difference in sensitivity between the two phenotypic assays. A bioinformatic algorithm based on a support vector machine using HIV V3 genotype data was able to achieve 86.5% and 79.7% concordance with the Trofile and TRT assays, respectively, approaching the degree of agreement between the two phenotype assays. In most cases, the phenotype assays and the bioinformatic approach gave similar results. However, in cases where there were differences in the tropism results, it was not clear which of the assays was "correct." X4 (CXCR4-using) minority species in clinically derived samples likely complicate the interpretation of both phenotypic and genotypic assessments of HIV tropism. 相似文献
258.
Lécuyer H Audibert J Bobigny A Eckert C Jannière-Nartey C Buu-Hoï A Mainardi JL Podglajen I 《Journal of clinical microbiology》2007,45(10):3474-3475
We report a case of non-ventilator-associated nosocomial pneumonia and septicemia due to Dolosigranulum pigrum, a rare gram-positive opportunistic pathogen. The organism was isolated from bronchoalveolar lavage fluid and blood of a debilitated patient. D. pigrum was identified after 16S rRNA gene sequencing. 相似文献
259.
A sertoli cell-specific knockout of connexin43 prevents initiation of spermatogenesis 总被引:1,自引:0,他引:1
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Brehm R Zeiler M Rüttinger C Herde K Kibschull M Winterhager E Willecke K Guillou F Lécureuil C Steger K Konrad L Biermann K Failing K Bergmann M 《The American journal of pathology》2007,171(1):19-31
The predominant testicular gap junctional protein connexin43 (cx43) is located between neighboring Sertoli cells (SCs) and between SCs and germ cells. It is assumed to be involved in testicular development, cell differentiation, initiation, and maintenance of spermatogenesis with alterations of its expression being correlated with various testicular disorders. Because total disruption of the cx43 gene leads to perinatal death, we generated a conditional cx43 knockout (KO) mouse using the Cre/loxP recombination system, which lacks the cx43 gene solely in SCs (SCCx43KO), to evaluate the SC-specific functions of cx43 on spermatogenesis in vivo. Adult SCCx43KO(-/-) mice showed normal testis descent and development of the urogenital tract, but testis size and weight were drastically lower compared with heterozygous and wild-type littermates. Histological analysis and quantitation of mRNA expression of germ cell-specific marker genes revealed a significant reduction in the number of spermatogonia but increased SC numbers/tubule with only a few tubules left showing normal spermatogenesis. Thus, SC-specific deletion of cx43 mostly resulted in an arrest of spermatogenesis at the level of spermatogonia or SC-only syndrome and in intratubular SC clusters. Our data demonstrate for the first time that cx43 expression in SCs is an absolute requirement for normal testicular development and spermatogenesis. 相似文献
260.
Biermann K Göke F Nettersheim D Eckert D Zhou H Kahl P Gashaw I Schorle H Büttner R 《The Journal of pathology》2007,213(3):311-318
Testicular germ cell tumours (TGCTs) are the most frequent cancer type in young men; 5% of these patients develop a second TGCT in the contralateral testis. The pathogenesis of TGCT is closely linked to primordial germ cells (PGCs) or gonocytes. The receptor tyrosine kinase (c-KIT) is necessary for migration and survival of PGCs and is expressed in intratubular neoplastic germ cells (IGCNUs) and seminomas. We studied the frequency of c-KIT exon 11 and 17 mutations in 155 unilateral (108 seminomas and 47 non-seminomas) and 22 bilateral (18 seminomas, two embryonal carcinomas, two IGCNU) cases. While no mutations were detected in exon 11, the mutation frequency in exon 17 was significantly higher in bilateral (14/22, 63.6%) compared to unilateral TGCT (10/155, 6.4%) (p < 0.001). Different activating mutations (Y823D, D816V, D816H and N822K) were detected in bilateral TGCT. Y823D mutation was identical in both testes in three cases and quantitative pyrosequencing showed that up to 76% of the cells analysed in tumour samples carried this mutation. One bilateral synchronous seminoma revealed a S821F mutation in one testis and a Y823D mutation contralaterally. To study the role of c-KIT in TGCT progression, we compared its expression in 41 seminomas and adjacent IGCNUs. Immunohistochemical analysis revealed that c-KIT expression was significantly reduced in seminomas compared to IGCNUs (p < 0.006) and that there were no significant changes in c-KIT mRNA copy numbers in progressed compared to low-stage seminomas. In summary, our study shows that patients with c-KIT mutations are more prone to develop a bilateral TGCT and suggests that in a portion of bilateral TGCTs, c-KIT mutations occur early during embryonal development, prior to the arrival of PGCs at the genital ridge. Furthermore, our findings show that c-KIT down-regulation occurs during the progression of IGCNU to seminoma. 相似文献