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41.
Haringman JJ Vinkenoog M Gerlag DM Smeets TJ Zwinderman AH Tak PP 《Arthritis research & therapy》2005,7(4):R862-R867
Analysis of biomarkers in synovial tissue is increasingly used in the evaluation of new targeted therapies for patients with
rheumatoid arthritis (RA). This study determined the intrarater and inter-rater reliability of digital image analysis (DIA)
of synovial biopsies from RA patients participating in clinical trials. Arthroscopic synovial biopsies were obtained before
and after treatment from 19 RA patients participating in a randomized controlled trial with prednisolone. Immunohistochemistry
was used to detect CD3+ T cells, CD38+ plasma cells and CD68+ macrophages. The mean change in positive cells per square millimetre for each marker was determined by different operators
and at different times using DIA. Nonparametric tests were used to determine differences between observers and assessments,
and to determine changes after treatment. The intraclass correlations (ICCs) were calculated to determine the intrarater and
inter-rater reliability. Intrarater ICCs showed good reliability for measuring changes in T lymphocytes (R = 0.87), plasma
cells (R = 0.62) and macrophages (R = 0.73). Analysis by Bland–Altman plots showed no systemic differences between measurements.
The smallest detectable changes were calculated and their discriminatory power revealed good response in the prednisolone
group compared with the placebo group. Similarly, inter-rater ICCs also revealed good reliability for measuring T lymphocytes
(R = 0.68), plasma cells (R = 0.69) and macrophages (R = 0.72). All measurements identified the same cell types as changing
significantly in the treated patients compared with the placebo group. The measurement of change in total positive cell numbers
in synovial tissue can be determined reproducibly for various cell types by DIA in RA clinical trials. 相似文献
42.
43.
The interfollicular dermis of adult human skin is partitioned into histologically and physiologically distinct papillary and reticular zones. Each of these zones contains a unique population of fibroblasts that differ in respect to their proliferation kinetics, rates at which they contract type I collagen gels, and in their relative production of decorin and versican. Here, site-matched papillary and reticular dermal fibroblasts couples were compared to determine whether each population interacted with keratinocytes in an equivalent or different manner. Papillary and reticular fibroblasts grown in monolayer culture differed significantly from each other in their release of keratinocyte growth factor (KGF) and granulocyte-macrophage colony stimulating factor (GM-CSF) into culture medium. Some matched fibroblast couples also differed in their constitutive release of interleukin-6 (IL-6). Papillary fibroblasts produced a higher ratio of GM-CSF to KGF than did corresponding reticular fibroblasts. Interactions between site-matched papillary and reticular couples were also assayed in a three-dimensional culture system where fibroblasts and keratinocytes were randomly mixed, incorporated into type I collagen gels, and allowed to sort. Keratinocytes formed distinctive cellular masses in which the keratinocytes were organized such that the exterior most layer of cells exhibited characteristics of basal keratinocytes and the interior most cells exhibited characteristics of terminally differentiated keratinocytes. In the presence of papillary dermal fibroblasts, keratinocyte masses were highly symmetrical and cells expressed all levels of differentiation markers. In contrast, keratinocyte masses that formed in the presence of reticular fibroblasts tended to have irregular shapes, and terminal differentiation was suppressed. Furthermore, basement membrane formation was retarded in the presence of reticular cells. These studies indicate that site-matched papillary and reticular dermal fibroblasts qualitatively differ in their support of epidermal cells, with papillary cells interacting more effectively than corresponding reticular cells. 相似文献
44.
Ganendren R Carter E Sorrell T Widmer F Wright L 《Microbes and infection / Institut Pasteur》2006,8(4):1006-1015
Secreted phospholipase B (PLB1), which contains three enzyme activities in the one protein, is necessary for the initiation of pulmonary infection by Cryptococcus neoformans and for dissemination from the lung via the lymphatics and blood. Adhesion to lung epithelium is the first step in this process, therefore we investigated the role of PLB1 in adhesion to a human lung epithelial cell line, A549, using C. neoformans var. grubii wild-type strain H99, a PLB1 deletion mutant (deltaplb1), and a reconstituted strain (deltaplb1rec). Adhesion of H99 and deltaplb1rec was approximately 69% greater than deltaplb1 at 4 h. Adhesion of deltaplb1 significantly increased after killing by chemicals or heat, and Fourier-transformed analysis by FTIR spectroscopy indicated this was due to changes in capsular and/or cell wall polysaccharides and proteins. Inhibition by specific PLB1 antibodies, or inhibitors of phospholipase B (PLB), but not lysophospholipase (LPL) or lysophospholipase transacylase (LPTA) activities decreased the adhesion of H99 and deltaplb1rec by 33-58%. Growth under conditions of osmotic stress and high glucose concentration increased both PLB secretion and subsequent cryptococcal adhesion. Dose-dependent increases (to 67%) in adhesion of live deltaplb1 were observed in the presence of 0.1-2 mM palmitic acid. We conclude that PLB1 plays a role in the binding of C. neoformans to host lung epithelial cells, possibly due to production of fatty acids from plasma membranes and/or surfactant by PLB activity. 相似文献
45.
Ryanne JM Lemmens Annick AA Timmermans Yvonne JM Janssen-Potten Rob JEM Smeets Henk AM Seelen 《BMC neurology》2012,12(1):1-17
Background
Loss of arm-hand performance due to a hemiparesis as a result of stroke or cerebral palsy (CP), leads to large problems in daily life of these patients. Assessment of arm-hand performance is important in both clinical practice and research. To gain more insight in e.g. effectiveness of common therapies for different patient populations with similar clinical characteristics, consensus regarding the choice and use of outcome measures is paramount. To guide this choice, an overview of available instruments is necessary. The aim of this systematic review is to identify, evaluate and categorize instruments, reported to be valid and reliable, assessing arm-hand performance at the ICF activity level in patients with stroke or cerebral palsy.Methods
A systematic literature search was performed to identify articles containing instruments assessing arm-hand skilled performance in patients with stroke or cerebral palsy. Instruments were identified and divided into the categories capacity, perceived performance and actual performance. A second search was performed to obtain information on their content and psychometrics.Results
Regarding capacity, perceived performance and actual performance, 18, 9 and 3 instruments were included respectively. Only 3 of all included instruments were used and tested in both patient populations. The content of the instruments differed widely regarding the ICF levels measured, assessment of the amount of use versus the quality of use, the inclusion of unimanual and/or bimanual tasks and the inclusion of basic and/or extended tasks.Conclusions
Although many instruments assess capacity and perceived performance, a dearth exists of instruments assessing actual performance. In addition, instruments appropriate for more than one patient population are sparse. For actual performance, new instruments have to be developed, with specific focus on the usability in different patient populations and the assessment of quality of use as well as amount of use. Also, consensus about the choice and use of instruments within and across populations is needed. 相似文献46.
Reinout Raijmakers Joyce JBC van Beers Mahmoud El-Azzouny Natasja FC Visser Borut Bo?i? Ger JM Pruijn Albert JR Heck 《Arthritis research & therapy》2012,14(3):R114-10
Introduction
Rheumatoid arthritis (RA) is an autoimmune disease characterized by inflammation of the joints and the presence of autoantibodies directed against proteins containing the non-standard arginine-derived amino acid citrulline. The protein fibrinogen, which has an essential role in blood clotting, is one of the most prominent citrullinated autoantigens in RA, particularly because it can be found in the inflamed tissue of affected joints. Here, we set out to analyze the presence of citrullinated endogenous peptides in the synovial fluid of RA and arthritic control patients.Methods
Endogenous peptides were isolated from the synovial fluid of RA patients and controls by filtration and solid phase extraction. The peptides were identified and quantified using high-resolution liquid chromatography-mass spectrometry.Results
Our data reveal that the synovial fluid of RA patients contains soluble endogenous peptides, derived from fibrinogen, containing significant amounts of citrulline residues and, in some cases, also phosphorylated serine. Several citrullinated peptides are found to be more abundantly present in the synovial fluid of RA patients compared to patients suffering from other inflammatory diseases affecting the joints.Conclusions
The increased presence of citrullinated peptides in RA patients points toward a possible specific role of these peptides in the immune response at the basis of the recognition of citrullinated peptides and proteins by RA patient autoantibodies. 相似文献47.
S Chen AJ de Craen Y Raz E Derhovanessian AC Vossen WG Rudi G Pawelec AB Maier 《Immunity & ageing : I & A》2012,9(1):18-7
ABSTRACT: BACKGROUND: Cytomegalovirus (CMV) infection has been reported to contribute to the pathogenesis of type 1 diabetes and post-transplantation diabetes. However, CMV infection has not been evaluated as a possible risk factor for type 2 diabetes. Our aim was to investigate potential associations between CMV seropositivity, CMV IgG antibody level and glucose regulation in the oldest old. RESULTS: CMV seropositive subjects were more likely to have type 2 diabetes (17.2% vs 7.9%, p = 0.016), had a higher level of HbA1c (p = 0.014) and higher non-fasting glucose (p = 0.024) in the oldest olds. These associations remained significant after adjustment for possible confounders. CMV IgG antibody level was not significantly associated with glucose regulation (all p > 0.05). CONCLUSIONS: In the oldest old, CMV seropositivity is significantly associated with various indicators of glucose regulation. This finding suggests that CMV infection might be a risk factor for the development of type 2 diabetes in the elderly. 相似文献
48.
Study design
A prospective treatment study with a new brace was conducted Objective. To evaluate radiological and subjective clinical results after one year conservative brace treatment with pressure onto lordosis at the thoracolumbar joint in children with scoliosis and kyphosis.Summary of background data
Conservative brace treatment of adolescent scoliosis is not proven to be effective in terms of lasting correction. Conservative treatment in kyphotic deformities may lead to satisfactory correction. None of the brace or casting techniques is based on sagittal forces only applied at the thoracolumbar spine (TLI= thoracolumbar lordotic intervention). Previously we showed in patients with scoliosis after forced lordosis at the thoracolumbar spine a radiological instantaneous reduction in both coronal curves of double major scoliosis.Methods
A consecutive series of 91 children with adolescent scoliosis and kyphosis were treated with a modified symmetric 30 degrees Boston brace to ensure only forced lordosis at the thoracolumbar spine. Scoliosis was defined with a Cobb angle of at least one of the curves [greater than or equal to] 25 degrees and kyphosis with or without a curve <25 degrees in the coronal plane. Standing radiographs were made i) at start, ii) in brace at beginning and iii) after one year treatment without brace.Results
Before treatment start ??in brace?? radiographs showed a strong reduction of the Cobb angles in different curves in kyphosis and scoliosis groups (sagittal n = 5 all p < 0.001, pelvic obliquity p < 0.001). After one year of brace treatment in scoliosis and kyphosis group the measurements on radiographs made without brace revealed an improvement in 3 Cobb angles each.Conclusion
Conservative treatment using thoracolumbar lordotic intervention in scoliotic and kyphotic deformities in adolescence demonstrates a marked improvement after one year also in clinical and postural criteria. An effect not obtained with current brace techniques. 相似文献49.
Steven W Kembel Evan Jones Jeff Kline Dale Northcutt Jason Stenson Ann M Womack Brendan JM Bohannan G Z Brown Jessica L Green 《The ISME journal》2012,6(8):1469-1479
Buildings are complex ecosystems that house trillions of microorganisms interacting with each other, with humans and with their environment. Understanding the ecological and evolutionary processes that determine the diversity and composition of the built environment microbiome—the community of microorganisms that live indoors—is important for understanding the relationship between building design, biodiversity and human health. In this study, we used high-throughput sequencing of the bacterial 16S rRNA gene to quantify relationships between building attributes and airborne bacterial communities at a health-care facility. We quantified airborne bacterial community structure and environmental conditions in patient rooms exposed to mechanical or window ventilation and in outdoor air. The phylogenetic diversity of airborne bacterial communities was lower indoors than outdoors, and mechanically ventilated rooms contained less diverse microbial communities than did window-ventilated rooms. Bacterial communities in indoor environments contained many taxa that are absent or rare outdoors, including taxa closely related to potential human pathogens. Building attributes, specifically the source of ventilation air, airflow rates, relative humidity and temperature, were correlated with the diversity and composition of indoor bacterial communities. The relative abundance of bacteria closely related to human pathogens was higher indoors than outdoors, and higher in rooms with lower airflow rates and lower relative humidity. The observed relationship between building design and airborne bacterial diversity suggests that we can manage indoor environments, altering through building design and operation the community of microbial species that potentially colonize the human microbiome during our time indoors. 相似文献
50.
Shi H Strader AD Sorrell JE Chambers JB Woods SC Seeley RJ 《American journal of physiology. Endocrinology and metabolism》2008,294(3):E630-E639
Leptin regulates energy balance and glucose homeostasis, at least in part, via activation of receptors in the arcuate nucleus of the hypothalamus located in proopiomelanocortin (POMC) neurons. Females have greater sensitivity to central leptin than males, suggested by a greater anorectic effect of central leptin administration in females. We hypothesized that the regulation of energy balance and peripheral glucose homeostasis of female rodents would be affected to a greater extent than in males if the action of leptin in POMC neurons were disturbed. Male and female mice lacking leptin receptors only in POMC neurons gained significantly more body weight and accumulated more body fat. However, female mice gained disproportionately more visceral adiposity than males, and this appeared to be largely the result of differences in energy expenditure. When maintained on a high-fat diet (HFD), both male and female mutants had higher levels of insulin following exogenous glucose challenges. Chow- and HFD-fed males but not females had abnormal glucose disappearance curves following insulin administrations. Collectively, these data indicate that the action of leptin in POMC neurons is sexually different to influence the regulation of energy balance, fat distribution, and glucose homeostasis. 相似文献