Lessons from an animal model that faithfully resembles human membranous nephropathy (MN) have informed our understanding of the pathogenesis of this organ-specific autoimmune disease and common cause ...of nephrotic syndrome. After it was established that the subepithelial immune deposits that characterize experimental MN form in situ when circulating antibodies bind to an intrinsic podocyte antigen, it was merely a matter of time before the human antigen was identified. The M-type phospholipase A2 receptor 1 (PLA2 R) represents the major target antigen in primary MN, and thrombospondin type 1 domain-containing 7A (THSD7A) was more recently identified as a minor antigen. Serologic tests for anti-PLA2 R and kidney biopsy specimen staining for PLA2 R show >90% specificity and 70% to 80% sensitivity for the diagnosis of primary MN in most populations. The assays distinguish most cases of primary MN from MN associated with other systemic diseases, and sequential anti-PLA2 R titers are useful to monitor treatment response. A positive pretransplantation test result for anti-PLA2 R is also helpful for predicting the risk for posttransplantation recurrence. Identification of target epitopes within PLA2 R and the genetic association of primary MN with class II major histocompatibility and PLA2R1 variants are 2 additional examples of our evolving understanding of this disease.
The pikromycin biosynthetic gene cluster contains the pikAV gene encoding a type II thioesterase (TEII). TEII is not responsible for polyketide termination and cyclization, and its
biosynthetic role ...has been unclear. During polyketide biosynthesis, extender units such as methylmalonyl acyl carrier protein
(ACP) may prematurely decarboxylate to generate the corresponding acyl-ACP, which cannot be used as a substrate in the condensing
reaction by the corresponding ketosynthase domain, rendering the polyketide synthase module inactive. It has been proposed
that TEII may serve as an âeditingâ enzyme and reactivate these modules by removing acyl moieties attached to ACP domains.
Using a purified recombinant TEII we have tested this hypothesis by using in vitro enzyme assays and a range of acyl-ACP, malonyl-ACP, and methylmalonyl-ACP substrates derived from either PikAIII or the loading
didomain of DEBS1 (6-deoxyerythronolide B synthase; AT L -ACP L ). The pikromycin TEII exhibited high K
m values (>100 μ m ) with all substrates and no apparent ACP specificity, catalyzing cleavage of methylmalonyl-ACP from both AT L -ACP L ( k
cat / K
m 3.3 ± 1.1 m
â1 s â1 ) and PikAIII ( k
cat / K
m 2.9 ± 0.9 m
â1 s â1 ). The TEII exhibited some acyl-group specificity, catalyzing hydrolysis of propionyl ( k
cat / K
m 15.8 ± 1.8 m
â1 s â1 ) and butyryl ( k
cat / K
m 17.5 ± 2.1 m
â1 s â1 ) derivatives of AT L -ACP L faster than acetyl ( k
cat / K
m 4.9 ± 0.7 m
â1 s â1 ), malonyl ( k
cat / K
m 3.9 ± 0.5 m
â1 s â1 ), or methylmalonyl derivatives. PikAIV containing a TEI domain catalyzed cleavage of propionyl derivative of AT L -ACP L at a dramatically lower rate than TEII. These results provide the first unequivocal in vitro evidence that TEII can hydrolyze acyl-ACP thioesters and a model for the action of TEII in which the enzyme remains primarily
dissociated from the polyketide synthase, preferentially removing aberrant acyl-ACP species with long half-lives. The lack
of rigorous substrate specificity for TEII may explain the surprising observation that high level expression of the protein
in Streptomyces venezuelae leads to significant (>50%) titer decreases.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
A cellular model system of differentiated human myotubes GASTER, M.; KRISTENSEN, S. R.; BECK-NIELSEN, H. ...
APMIS : acta pathologica, microbiologica et immunologica Scandinavica,
November 2001, Volume:
109, Issue:
11
Journal Article
Peer reviewed
The aim of this study was to select an effective and stable protocol for the differentiation of human satellite cells (Sc) and to identify the optimal time period for the experimental use of ...differentiated human Sc‐cultures. In order to identify the differentiation conditions which give a good survival of myotubes and a high grade of differentiation, Sc‐cultures were induced to differentiate in media supplemented with either 2% fetal calf serum (FCS) 2% horse serum (HS) or 10% HS. Based on higher CK‐activities in cultures differentiating in FCS‐supplemented media compared to horse sera, fetal calf serum was chosen to induce differentiation. The ATP, DNA and protein content increased during the first 4 days after induction of differentiation and was followed by a period with minor changes. The maximal differences of ATP, DNA and protein between days 4–10 were evaluated and the differences in the three components were found to be less than 20% of the average value with a certainity of more than 0.9. Day 8‐myotubes were investigated morphologically and were found immunoreactive for fast myosin, and expressed areas with clear cross striation. We recommend the use of differentiated Sc‐cultures in the period from day 4 to 8 after induction of differentiation as only minor differentation‐related changes will take place in the cells during this period of time.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Summary Background Data from early-stage studies suggested that interleukin (IL)-4 and IL-13 are requisite drivers of atopic dermatitis, evidenced by marked improvement after treatment with ...dupilumab, a fully-human monoclonal antibody that blocks both pathways. We aimed to assess the efficacy and safety of several dose regimens of dupilumab in adults with moderate-to-severe atopic dermatitis inadequately controlled by topical treatments. Methods In this randomised, placebo-controlled, double-blind study, we enrolled patients aged 18 years or older who had an Eczema Area and Severity Index (EASI) score of 12 or higher at screening (≥16 at baseline) and inadequate response to topical treatments from 91 study centres, including hospitals, clinics, and academic institutions, in Canada, Czech Republic, Germany, Hungary, Japan, Poland, and the USA. Patients were randomly assigned (1:1:1:1:1:1), stratified by severity (moderate or severe, as assessed by Investigator's Global Assessment) and region (Japan vs rest of world) to receive subcutaneous dupilumab: 300 mg once a week, 300 mg every 2 weeks, 200 mg every 2 weeks, 300 mg every 4 weeks, 100 mg every 4 weeks, or placebo once a week for 16 weeks. We used a central randomisation scheme, provided by an interactive voice response system. Drug kits were coded, providing masking to treatment assignment, and allocation was concealed. Patients on treatment every 2 weeks and every 4 weeks received volume-matched placebo every week when dupilumab was not given to ensure double blinding. The primary outcome was efficacy of dupilumab dose regimens based on EASI score least-squares mean percentage change (SE) from baseline to week 16. Analyses included all randomly assigned patients who received one or more doses of study drug. This trial is registered with ClinicalTrials.gov , number NCT01859988. Findings Between May 15, 2013, and Jan 27, 2014, 452 patients were assessed for eligibility, and 380 patients were randomly assigned. 379 patients received one or more doses of study drug (300 mg once a week n=63, 300 mg every 2 weeks n=64, 200 mg every 2 weeks n=61, 300 mg every 4 weeks n=65, 100 mg every 4 weeks n=65; placebo n=61). EASI score improvements favoured all dupilumab regimens versus placebo (p<0·0001): 300 mg once a week (−74% SE 5·16), 300 mg every 2 weeks (−68% 5·12), 200 mg every 2 weeks (−65% 5·19), 300 mg every 4 weeks (−64% 4·94), 100 mg every 4 weeks (−45% 4·99); placebo (−18% 5·20). 258 (81%) of 318 patients given dupilumab and 49 (80%) of 61 patients given placebo reported treatment-emergent adverse events; nasopharyngitis was the most frequent (28% and 26%, respectively). Interpretation Dupilumab improved clinical responses in adults with moderate-to-severe atopic dermatitis in a dose-dependent manner, without significant safety concerns. Our findings show that IL-4 and IL-13 are key drivers of atopic dermatitis. Funding Sanofi and Regeneron Pharmaceuticals.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Background and purpose: Predictive assays of the response of tumor and normal tissues in individual patients offer the possibility of individualized prognosis and treatment decisions. For this ...purpose a variety of assays are currently being explored. The impact of tumor volume on radiotherapy outcome has long been recognized and in this paper its predictive potential is investigated.
Methods: Re-evaluation of clinical data from the literature.
Results: Tumor volume significantly influences radiotherapy outcome and in many sites it is likely a superior prognostic indicator to tumor stage, which reflects tumor size only partially and is mainly correlated to operability. Tumors even of identical stage may vary by factors of more than 100 in volume and neglect of this heterogeneity clearly reduces the power of a study considerably. The precision requirements for the measurement of tumor volume are small; ±50% is sufficient for reasonable results.
Conclusion: The data evaluated here suggest that tumor volume is the most precise and most relevant predictor of radiotherapy outcome. Its determination is achievable with sufficient accuracy in most radiotherapy departments. Individual tumor volume should always be reported in clinical studies and considered in data analyses.
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IJS, IMTLJ, KILJ, KISLJ, NUK, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
We report on a new measurement of the parity-violating asymmetry in quasielastic electron scattering from the deuteron at backward angles at Q2=0.038 (GeV/c)2. This quantity provides a determination ...of the neutral weak axial vector form factor of the nucleon, which can potentially receive large electroweak corrections. The measured asymmetry A=-3.51+/-0.57 (stat)+/-0.58 (syst) ppm is consistent with theoretical predictions. We also report on updated results of the previous experiment at Q2=0.091 (GeV/c)2, which are also consistent with theoretical predictions.
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CMK, CTK, FMFMET, IJS, NUK, PNG, UM
The violation of mirror symmetry in the weak force provides a powerful tool to study the internal structure of the proton. Experimental results have been obtained that address the role of strange ...quarks in generating nuclear magnetism. The measurement reported here provides an unambiguous constraint on strange quark contributions to the proton's magnetic moment through the electron-proton weak interaction. We also report evidence for the existence of a parity-violating electromagnetic effect known as the anapole moment of the proton. The proton's anapole moment is not yet well understood theoretically, but it could have important implications for precision weak interaction studies in atomic systems such as cesium.
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BFBNIB, NMLJ, NUK, PNG, SAZU, UL, UM, UPUK
Background. People who consume a diet high in vegetables and fruits have a lower risk of cancer of the large bowel. Antioxidant vitamins, which are present in vegetables and fruits, have been ...associated with a diminished risk of cancers at various anatomical sites. We conducted a randomized, controlled clinical trial to test the efficacy of beta carotene and vitamins C and E in preventing colorectal adenoma, a precursor of invasive cancer. Methods. We randomly assigned 864 patients, using a two-by-two factorial design, to four treatment groups, which received placebo, beta carotene (25 mg daily), vitamin C (1 g daily) and vitamin E (400 mg daily), or beta carotene plus vitamins C and E. In order to identity new adenomas, we performed complete colonoscopic examinations in the patients one year and four years after they entered the study. The primary end points for analyses were new adenomas identified after the first of these two follow-up examinations. Results. Patients adhered well to the prescribed regimen, and 751 completed the four-year clinical trial. There was no evidence that either beta carotene or vitamins C and E reduced the incidence of adenomas; the relative risk for beta carotene was 1.01 (95 percent confidence interval, 0.85 to 1.20); for vitamins C and E, it was 1.08 (95 percent confidence interval, 0.91 to 1.29). Neither treatment appeared to be effective in any subgroup of patients or in the prevention of any subtype of polyp defined by size or location. Conclusions. The lack of efficacy of these vitamins argues against the use of supplemental beta carotene and vitamins C and E to prevent colorectal cancer. Although our data do not prove definitively that these antioxidants have no anticancer effect, other dietary factors may make more important contributions to the reduction in the risk of cancer associated with a diet high in vegetables and fruits.
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