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In lakes, phytoplankton sequester atmospheric carbon dioxide (CO 2 ) and store it in the form of biomass organic carbon (OC); however, only a small fraction of the OC remains buried, while the remaining part is recycled to the atmosphere as CO 2 and methane (CH 4 ). This has the potential effect of adding CO 2 -equivalents (CO 2 -eq) to the atmosphere and producing a warming effect due to the higher radiative forcing of CH 4 relative to CO 2 . Here we show a 3.1-fold increase in CO 2 -eq emissions over a 100-year horizon, with the effect increasing with global warming intensity. Climate warming has stimulated phytoplankton growth in many lakes worldwide, which, in turn, can feed back CO 2 -eq and create a positive feedback loop between them. In lakes where phytoplankton is negatively impacted by climate warming, the CO 2 -eq feedback capacity may diminish gradually with the ongoing climate warming., Competing Interests: Competing interests: The authors declare no competing interests., (© 2024. The Author(s).)

High refractive index dielectric nanoantennas strongly modify the decay rate via the Purcell effect through the design of radiative channels. Due to their dielectric nature, the field is mainly confined inside the nanostructure and in the gap, which is hard to probe with scanning probe techniques. Here we use single-molecule fluorescence lifetime imaging microscopy (smFLIM) to map the decay rate enhancement in dielectric GaP nanoantenna dimers with a median localization precision of 14 nm. We measure, in the gap of the nanoantenna, decay rates that are almost 30 times larger than on a glass substrate. By comparing experimental results with numerical simulations we show that this large enhancement is essentially radiative, contrary to the case of plasmonic nanoantennas, and therefore has great potential for applications such as quantum optics and biosensing., (© 2024. The Author(s).)

Andrographolide, a bioactive compound found in Andrographis paniculata , has gained significant attention for its potential therapeutic properties. Despite its promising benefits, the understanding of its side effects and underlying mechanisms remains limited. Here, we investigated the impact of andrographolide in Saccharomyces cerevisiae and observed that andrographolide induced cytotoxicity, particularly when oxidative phosphorylation was active. Furthermore, andrographolide affected various cellular processes, including vacuole fragmentation, endoplasmic reticulum stress, lipid droplet accumulation, reactive oxygen species levels, and compromised cell integrity. Moreover, we unexpectedly observed that andrographolide induced the precipitation of biomolecules secreted from yeast cells, adding an additional source of stress. Overall, this study provides insights into the cellular effects and potential mechanisms of andrographolide in yeast, shedding light on its side effects and underlying cytotoxicity pathways.

Introduction: Both rituximab (RTX) and cyclophosphamide (CYC) are effectively used in combination with steroids as remission induction therapy for patients with antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV). Several studies have shown that the effect on achieving (clinical) remission, frequency and severity of relapses is equivalent for both therapies, but there is accumulating data that the long-term safety profile of RTX might outperform CYC. Combination of RTX with low-dose CYC (LD-CYC) has been investigated in only a few uncontrolled cohort studies, in which clinical remission and a favourable immunological state with low relapse rates was quickly achieved. In this randomised controlled trial, we aim to investigate whether the combination treatment (RTX+LD CYC) is superior in comparison to standard care with RTX only., Methods and Analysis: This study is an open-label, multicentre, 1:1 randomised, prospective study for patients with AAV with generalised disease, defined as involvement of major organs, that is, kidneys, lungs, heart and nervous system. In total, 100 patients will be randomised 1:1 to receive either remission induction therapy with standard of care (RTX) or combination treatment (RTX+LD CYC) in addition to steroids and both arms are followed by maintenance with RTX retreatments (tailored to B-cell and ANCA status). Our primary outcome is the number of retreatments needed to maintain clinical remission over 2 years. Secondary outcomes are relevant clinical endpoints, safety, quality of life and immunological responses., Ethics and Dissemination: This study has received approval of the Medical Ethics Committee of the Leiden University Medical Center (P18.216, NL67515.058.18, date: 7 March 2019). The results of this trial (positive and negative) will be submitted for publication in relevant peer-reviewed publications and the key findings presented at national and international conferences., Trial Registration Number: NCT03942887., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2022. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

The intensity of marine heatwaves is increasing due to climate change. Heatwaves may affect macroinvertebrates' bioturbating behavior in intertidal areas, thereby altering the deposition-erosion balance at tidal flats. Moreover, small-scale topographic features on tidal flats can create tidal pools during the low tide, thus changing the heat capacity of tidal flats. These pools could then potentially operate as refuge environments during marine heatwaves. We studied behavior responses to heat waves using the well-known bioturbating cockle Cerastoderma edule as a model species. Different temperature regimes (i.e., fluctuating between 20 and 40 °C) and micro-topographies (i.e., presence vs. absence of tidal water pools) were mimicked in a mesocosm experiment with regular tidal regimes. Our results demonstrate that behavioral responses to heat stress strongly depend on the site-specific morphological features. Cockles covered by shallow water pools moved up when exposed to thermal stress, while burrowing deeper into the sediment in the absence of water pools. But in both cases, their migratory behavior increased under heat stress compared to regular ambient treatments. Moreover, long-term cumulative heat stress increased cockles' respiration rates and decreased their health conditions, causing mass mortality after four weeks of gradually increasing heat exposure. Overall, the present findings provide the first insights into how bioturbating behavior on tidal flats may change in response to global warming., Competing Interests: Declaration of competing interest The authors have no conflicts of interest to disclose and have all approved this submission., (Copyright © 2022 The Authors. Published by Elsevier B.V. All rights reserved.)

Driven by winds, the distribution of algae is often noticeably patchy at kilometer scales in shallow lakes. The decomposition of the settled algal biomass may affect nitrogen (N) biogeochemical cycles and thereby N loss in sediments. In this study, we investigated sediment denitrification N-loss patterns along algal migration pathway in Taihu Lake, a shallow and eutrophic lake in China, and found that wind-induced algal migration in the overlying water manipulated the temporal and spatial patterns of denitrification N-loss in sediments. A N loss hotspot in sediments was created in the algae concentrated zone, where N loss was, however, temporarily inhibited during algal bloom seasons and generally exhibited a negative relationship with algal biomass. In the zone where algae have left, sediment N loss rate was relatively low and positively correlated with algal biomass. The decay of algal biomass generated organic carbon and created anoxia, favoring denitrification, while excessive algal biomass could deplete oxygen and inhibit nitrification, causing nitrate limitation for denitrification. Piecewise linear regression analysis indicated that algal biomass of Chl-a > 73.0 μg/L in the overlying water could inhibit denitrification N-loss in sediments. This study adds to our understanding of N biogeochemical cycles in shallow eutrophic lakes., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Lake eutrophication is a pervasive problem globally, particularly serious in agricultural and densely populated areas. Whenever nutrients nitrogen and phosphorus do not limit phytoplankton growth directly, high growth rates will rapidly lead to biomass increases causing self-shading and light-limitation, and eventually CO 2 depletion. The paradigm of phytoplankton limitation by nutrients and light is so pervasively established, that the lack of nutrient limitation is ordinarily interpreted as sufficient evidence for the condition of light limitation, without considering the possibility of limitation by inorganic carbon. Here, we firstly evaluated how frequently CO 2 undersaturation occurs in a set of eutrophic lakes in the Pampa plains. Our results confirm that conditions of CO 2 undersaturation develop much more frequently (yearly 34%, summer 44%) in these agriculturally impacted lakes than in deep, temperate lakes in forested watersheds. Secondly, we used Generalized Additive Models to fit trends in CO 2 concentration considering three drivers: total incident irradiance, chlorophyll a concentration, and lake depth; in eight multi-year datasets from eutrophic lakes from Europe, North and South America, Asia and New Zealand. CO 2 depletion was more often observed at high irradiance levels, and shallow water. CO 2 depletion also occurred at high chlorophyll concentration. Finally, we identified occurrences of light- and carbon-limitation at the whole-lake scale. The different responses of chlorophyll a and CO 2 allowed us to develop criteria for detecting conditions of CO 2 limitation. For the first time, we provided whole-lake evidence of carbon limitation of phytoplankton biomass. CO 2 increases and eutrophication represent two major and converging environmental problems that have additive and contrasting effects, promoting phytoplankton, and also leading to carbon depletion. Their interactions deserve further exploration and imaginative approaches to deal with their effects., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Inland waters are considered hotspots of greenhouse gas (GHG) emissions and have been extensively researched. Static chamber (STAT) and thin boundary layer (BLE) are two commonly used methods for analyzing diffusive GHG emissions from inland waters. However, the STAT method is often disturbed by GHG bubbles; meanwhile, many kinds of headspace gas are used in the BLE method, but the differences between their diffusive GHG emission analysis results are not understood. In this study, the chamber in the STAT method was modified to combat the disturbances from GHG bubbles, and the typically used gases for the BLE method, namely, pure nitrogen, air, and filtered air, were comparatively studied. Results demonstrated that the modified chamber could effectively prevent the invasion of GHG bubbles; it increased the success rate from 67 to 90% in the field test, with no obvious impacts on the results of the GHG emission analyses. The use of air and filtered air in the BLE method yielded the lower values of GHG emissions relative to pure nitrogen, and this finding was potentially attributed to the inhibition effects of the residual GHGs and high humidity in air and filtered air on the extraction of diffusive GHGs from the surface water. This study improved the commonly used methods for diffusive GHG emission analysis, and the current findings are beneficial to the study of GHG emissions from inland waters.

In eutrophic lakes, the decay of settled algal biomass generates organic carbon and consumes oxygen, favoring sediment nitrogen loss via denitrification. However, persistent winds can cause algae to accumulate into dense mats, with uncertain impacts on sediment nitrogen removal. In this study, we investigated the effects of algal accumulation on sediment nitrogen removal in a shallow and eutrophic Chinese lake, Taihu. We found that experimental treatments of increased algal accumulation were associated with decreased sediment nitrogen losses, indicating the potential for a break in coupled nitrification-denitrification. Likewise, field measurements indicated similar decreases in sediment nitrogen losses when algal accumulation occurred. It is possibly caused by the decay of excess algal biomass, which likely depleted dissolved oxygen, and could have inhibited nitrification and thereby denitrification in sediments. We estimate that if such algal accumulations occurred over 20% or 10% of lake area in Taihu, sediment nitrogen removal rates decreased from 835.6 to 167.2 and 77.2 μmol N m -2 h -1 , respectively, during algal accumulation period. While nitrogen removal may recover later, the apparent nitrogen removal decrease may create a window for algal proliferation and intensification. This study advances our knowledge on the impacts of algal blooms on nitrogen removal in shallow eutrophic lakes.

Introduction: Despite the availability of several guidelines on the diagnosis and treatment of antineutrophil cytoplasmic antibody-associated vasculitis (AAV), clinical routine practice will only improve when an implementation strategy is in place to support clinical decision making and adequate implementation of guidelines. We describe here an initiative to establish national and multidisciplinary consensus on broad aspects of the diagnosis and treatment of AAV relevant to daily clinical practice in the Netherlands., Methods: A multidisciplinary working group of physicians in the Netherlands with expertise on AAV addressed the broad spectrum of diagnosis, terminology, and immunosuppressive and non-immunosuppressive treatment, including an algorithm for AAV patients. Based on recommendations from (inter)national guidelines, national consensus was established using a Delphi-based method during a conference in conjunction with a nationally distributed online consensus survey. Cut-off for consensus was 70% (dis)agreement., Results: Ninety-eight professionals were involved in the Delphi procedure to assess consensus on 50 statements regarding diagnosis, treatment, and organisation of care for AAV patients. Consensus was achieved for 37/50 statements (74%) in different domains of diagnosis and treatment of AAV including consensus on the treatment algorithm for AAV., Conclusion: We present a national, multidisciplinary consensus on a diagnostic strategy and treatment algorithm for AAV patients as part of the implementation of (inter)national guideline-derived recommendations in the Netherlands. Future studies will focus on evaluating local implementation of treatment protocols for AAV, and assessments of current and future clinical practice variation in the care for AAV patients in the Netherlands.

Background: Patients with end-stage renal disease who are undergoing dialysis are reported to be at high risk of sudden cardiac death (SCD), and to date, no therapy has been shown to be effective in reducing this risk. The feasibility and value of prophylactic implantable cardioverter-defibrillator (ICD) implantation to prevent SCD is uncertain., Methods: We conducted the ICD2 trial (Implantable Cardioverter-Defibrillator in Dialysis Patients), a prospective, randomized, controlled study investigating the value and safety of ICD implantation to prevent SCD in 200 patients on dialysis with a left ventricular ejection fraction ≥35%, after adequate screening and optimization of other treatments. The primary end point was SCD. Secondary end points were all-cause mortality and ICD-related complications., Results: The trial was stopped as per the recommendation of the data and safety monitoring board for futility reasons after inclusion of 188 patients, 97 in the ICD group and 91 in the control group. The median duration of follow-up was 6.8 years (interquartile range, 3.8-8.8 years). SCD occurred in 19 of 188 cases (10.1%), 11 of 97 in the ICD group and 8 of 91 in the control group. The cumulative SCD incidence at 5 years was 9.7% (95% CI, 3.3%-16.2%) in the ICD group and 7.9% (95% CI, 1.7-14.0%) in the control group, resulting in a hazard ratio of 1.32 (95% CI, 0.53-3.29; P=0.55). Overall, 99 of 188 patients died (52.7%), 52 in the ICD group and 47 in the control group. Five-year survival probability was 50.6% (95% CI, 39.8%-61.5%) in the ICD group and 54.5% (95% CI, 43.0-66.0%) in the control group, resulting in a hazard ratio of 1.02 (95% CI, 0.69-1.52; P=0.92). Among 80 patients who received an ICD, 25 adverse events related to ICD implantation occurred., Conclusions: In a well-screened and well-treated population undergoing dialysis, prophylactic ICD therapy did not reduce the rate of SCD or all-cause mortality, which remained high., Clinical Trial Registration: URL: http://www.controlled-trials.com . Unique identifier: ISRCTN20479861.

Background: Although the efficacy of iron sucrose (IS) and ferric carboxymaltose (FCM) in treating anemia in hemodialysis (HD) patients has been studied individually, a comparison of these two intravenous iron formulations has not yet been performed in HD patients., Methods: We performed a retrospective audit on records of 221 stable HD patients from different HD centers in the Netherlands, who were switched from IS to FCM on a 1:1 ratio. To assess the effect of the switch on iron status parameters, data from 3 time points before and 3 time points after the switch were analyzed using linear mixed effects models. Subanalyses were done in 2 subgroups of patients anemic or iron deficient at baseline., Results: Hemoglobin increased in all groups (anemic [1.4 g/dL, P < 0.001] iron deficient [0.6 g/dL, P < 0.001]), while the weekly iron dose was significantly lower when patients received FCM compared to IS (48 vs 55 mg/week, P = 0.04). Furthermore, serum ferritin and transferrin saturation increased in all groups (anemic [64 μg/L, 5.0%, P < 0.001] iron deficient [76 μg/L, 3.6%, P < 0.001]). Finally, the darbepoetin α dose decreased significantly in all groups (anemic [- 16 μg/wk., P = 0.01] iron deficient [- 11 μg/wk., P < 0.001])., Conclusions: In this real-life study in HD patients, a switch from IS to FCM resulted in an improvement of iron status parameters despite a lower weekly dose of FCM. Furthermore, the ESA dose was reduced during FCM, while hemoglobin levels increased.

Turbulent mixing is enhanced in shallow lakes. As a result, exchanges across the air-water and sediment-water interfaces are increased, causing these systems to be large sources of greenhouse gases. This study investigated the effects of turbulence on carbon dioxide (CO 2 ) and methane (CH 4 ) emissions in shallow lakes using simulated mesocosm experiments. Results demonstrated that turbulence increased CO 2 emissions, while simultaneously decreasing CH 4 emissions by altering microbial processes. Under turbulent conditions, a greater fraction of organic carbon was recycled as CO 2 instead of CH 4 , potentially reducing the net global warming effect because of the lower global warming potential of CO 2 relative to CH 4 . The CH 4 /CO 2 flux ratio was approximately 0.006 under turbulent conditions, but reached 0.078 in the control. The real-time quantitative PCR analysis indicated that methanogen abundance decreased and methanotroph abundance increased under turbulent conditions, inhibiting CH 4 production and favoring the oxidation of CH 4 to CO 2 . These findings suggest that turbulence may play an important role in the global carbon cycle by limiting CH 4 emissions, thereby reducing the net global warming effect of shallow lakes., (Copyright © 2018. Published by Elsevier B.V.)

Light-emitting silicon nanoparticles (Si-NPs) are interesting for lighting applications due to their nontoxicity, chemical robustness, and photostability; however, they are not practically considered due to their low emission efficiencies. While large Si-NPs emitting in the red to infrared spectral region show ensemble emission quantum efficiencies up to 60%, the emission efficiencies of smaller Si-NPs, emitting in the visible spectral range, are far lower, typically below 10-20%. In this work, we test this efficiency limit by measuring for the first time the internal quantum efficiency (IQE), i.e., the higher bound of the emission quantum efficiency, considering only the emissive NPs within the ensemble, of Si-NPs emitting in the visible spectral range between 350 and 650 nm. On the basis of photoluminescence decay measurements in a Drexhage geometry, we show that Si-NPs with organic passivation (C:Si-NPs) can have high direct-bandgap-like radiative rates, which enable a high IQE over ∼50%. In this way, we demonstrate that Si-NPs can in principle be considered a competitive candidate as a phosphor in lighting applications and medical imaging also in the visible spectral range. Moreover, our findings show that the reason for the much lower ensemble emission efficiency is due to the fact that the ensemble consists of a low fraction of emissive NPs, most likely due to a low PL "blinking" duty cycle., Competing Interests: The authors declare no competing financial interest.

Background/aims: In hemodialysis (HD) patients, the bromcresol green (BCG) assay overestimates, whereas the bromcresol purple (BCP) assay underestimates albumin concentration. Since corrected calcium concentrations depend on albumin, the albumin assay may have implications for the management of bone mineral disorders., Methods: A subset of patients from CONTRAST, a cohort of prevalent HD patients, was analyzed. Bone mineral parameters and prescription of medication were compared between patients in whom albumin was assessed by BCP versus BCG., Results: Albumin was assessed by BCP in 331 patients (9 of 25 centers) and by BCG in 175 patients (16 of 25 centers). Albumin was the lowest in the BCP group (34.5 ± 4.2 vs. 40.3 ± 3.1 g/L; p < 0.0005). Measured calcium levels and the prescription of calcium-based phosphate binders were similar in both groups. Corrected calcium levels, however, were markedly higher in the BCP group (2.45 ± 0.18 vs. 2.33 ± 0.18 mmol/L; p < 0.0005)., Conclusion: These findings suggest that calcium levels are not corrected for albumin in clinical practice when considering the prescription of calcium-free or calcium-based phosphate-binders in dialysis patients., (© 2018 The Author(s) Published by S. Karger AG, Basel.)

Carbon dots (CDs) are carbon-based fluorescent nanoparticles that can exhibit excitation-dependent photoluminescence (PL) "tunable" throughout the entire visible range, interesting for optoelectronic and imaging applications. The mechanism underlying this tunable emission remains largely debated, most prominently being ascribed to dot-to-dot variations that ultimately lead to excitation-dependent ensemble properties. Here, single-dot spectroscopy is used to elucidate the origin of the excitation-dependent PL of CDs. It is demonstrated that already single CDs exhibit excitation-dependent PL spectra, similar to those of the CD ensemble. The single dots, produced by a facile one-step synthesis from chloroform and diethylamine, exhibit emission spectra with several characteristic peaks differing in emission peak position and spectral width and shape, indicating the presence of distinct emission sites on the CDs. Based on previous work, these emission sites are related to the sp 2 subregions in the carbon core, as well as the functional groups on the surface. These results confirm that it is possible to integrate and engineer different types of electronic transitions at the nanoscale on a single CD, making these CDs even more versatile than organic dyes or inorganic quantum dots and opening up new routes toward light-emission engineering., (© 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Background: Renal involvement in antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) requires prompt and aggressive immunosuppressive therapy. The aim of this study was to evaluate screening practice for renal involvement in AAV and its potential effect on renal outcomes., Methods: Between 2005 and 2015, ANCA-positive AAV patients in a teaching hospital in the Netherlands were retrospectively included. Complete screening for renal involvement was defined as: assessment of erythrocyturia, proteinuria and serum creatinine within two weeks of the diagnosis of AAV. Characteristics at presentation and at 12 months were compared between patients with and without complete screening., Results: A total of 109 AAV patients (63% male) were identified with a mean age of 62 ±; 14 years. Complete screening for renal involvement was performed in 90 of the 109 patients (83%). Patients with incomplete screening had a lower serum creatinine (86 ±; 53 vs. 190 ±; 185 μmol/l, p < 0.001) and were more often diagnosed outside the renal department (100% vs. 78%, p = 0.02). Three patients with incomplete screening had a rise in serum creatinine of ≥ 30% at 12 months. Incomplete screening was not associated with the development of end-stage renal disease. Urine analysis of patients with renal biopsy-proven AAV (n = 31) showed erythrocyturia in 58% after one sample and in 94% after three samples., Conclusion: Screening for renal involvement in AAV was suboptimal, primarily in patients who presented outside the renal department. A higher sensitivity for erythrocyturia is achieved if urine analysis is repeated. Incomplete screening may lead to renal impairment if renal involvement is not treated appropriately.

Currently no validated diagnostic system for antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is available. Therefore, diagnosing AAV is often challenging. We aimed to identify factors that lead to a clinical diagnosis AAV in ANCA positive patients in a teaching hospital in The Netherlands.In this study, all patients that tested positive for ANCA proteinase 3 (PR3) and/or myeloperoxidase (MPO) between 2005 and 2015 were analysed. Patients with a clinical diagnosis of AAV were compared with patients without a clinical diagnosis of AAV. Clinical symptoms and laboratory variables at presentation, including the ANCA titre, were collected for both patients with and without AAV. Clinical and laboratory variables related with AAV were investigated, using multivariable logistic regression.Two hundred thirty seven consecutive patients with a positive ANCA were included, of whom 119 were clinically diagnosed with AAV. Of the 118 ANCA positive patients without AAV, 87 patients had an alternative diagnosis, including inflammatory bowel disease (n = 24), other rheumatic diseases (n = 23), infection (n = 11), malignancy (n = 4), and other diagnoses (n = 25). In a multivariable regression model, a high ANCA titre (odds ratio [OR] 14.16, 95% confidence interval [CI] 6.93-28.94) and a high number of affected organ systems (OR 7.67, 95% CI 3.69-15.94) were associated with AAV.MPO and PR3 ANCA can be positive in a variety of diseases that mimic AAV. A higher ANCA titre and multiple affected organ systems may help to discriminate between AAV and other systemic illnesses in anti-PR3 and anti-MPO positive patients. A diagnostic scoring system incorporating these factors should be considered., Competing Interests: The authors have no conflicts of interest to disclose.

Beneficial mutations fuel adaptation by altering phenotypes that enhance the fit of organisms to their environment. However, the phenotypic effects of mutations often depend on ecological context, making the distribution of effects across multiple environments essential to understanding the true nature of beneficial mutations. Studies that address both the genetic basis and ecological consequences of adaptive mutations remain rare. Here, we characterize the direct and pleiotropic fitness effects of a collection of 21 first-step beneficial mutants derived from naïve and adapted genotypes used in a long-term experimental evolution of Escherichia coli. Whole-genome sequencing was able to identify the majority of beneficial mutations. In contrast to previous studies, we find diverse fitness effects of mutations selected in a simple environment and few cases of genetic parallelism. The pleiotropic effects of these mutations were predominantly positive but some mutants were highly antagonistic in alternative environments. Further, the fitness effects of mutations derived from the adapted genotypes were dramatically reduced in nearly all environments. These findings suggest that many beneficial variants are accessible from a single point on the fitness landscape, and the fixation of alternative beneficial mutations may have dramatic consequences for niche breadth reduction via metabolic erosion., (© 2016 The Author(s). Evolution © 2016 The Society for the Study of Evolution.)

Calcific uraemic arteriolopathy (CUA) is a rare disease and continues to be a clinical challenge. The typical course of CUA is characterized by painful skin discolouration and induration evolving to necrotic ulcerations. Medial calcification of cutaneous arterioles and extensive extracellular matrix remodelling are the hallmarks of CUA. The epidemiology and risk factors associated with this disease are still not fully understood. Moreover, CUA treatment strategies vary significantly among centres and expert recommendations are heterogeneous. Registries may provide important insights and information to increase our knowledge about epidemiology and clinical aspects of CUA and may help to optimize its therapeutic management. In 2006, we established an internet-based registry in Germany (www.calciphylaxie.de) to allow online notification of patients with established or suspected CUA. The registry includes a comprehensive database with questions covering >70 parameters and items regarding patient-related and laboratory data, clinical background and presentation as well as therapeutic strategies. The next phase will be to allow international patient registration via www.calciphylaxis.net as part of the multinational EuCalNet (European Calciphylaxis Network) initiative, which is supported by the ERA-EDTA scientific working group 'CKD-MBD'. Based on the valuable experience with the previous German CUA registry, EuCalNet will be a useful tool to collect data on the rare disease CUA and may become a basis for prospective controlled trials in the near future.

Background: Dialysis patients suffer from a high burden of cardiovascular disease (CVD). Partly this is due to progressive deterioration of calcium-phosphate homeostasis. Previous studies suggested that besides FGF-23, low levels of Klotho, a protein linked to aging, might constitute a key factor in this detrimental relationship. The purpose of the present study was to determine the relationship between serum Klotho (sKlotho) and the presence of CVD in dialysis patients., Methods: Plasma levels of sKlotho were measured in a cohort of dialysis patients and related to left ventricular (LV) dysfunction (defined as a LV ejection fraction<45%) and LV mass using echocardiography. Coronary artery disease (CAD) and calcification score were assessed using computed tomography angiography. Abdominal aortic calcification score (AACscore) was measured by abdominal X-ray., Results: We included 127 dialysis patients, 67±7 years old, 76% male, 67% on hemodialysis, median sKlotho 460 pg/mL (25th-75th percentile 350-620 pg/mL). Patients with a low sKlotho (<460 pg/mL) showed significantly more CAD (81% versus 61%; p=0.02) and LV dysfunction (19% versus 3%; p<0.01). However, after adjusting for confounders, sKlotho was not independently associated with the presence of CVD or the AACscore., Conclusions: In the present cohort of dialysis patients, sKlotho was not independently associated with CVD. However, patients with a low sKlotho level (<460 pg/mL) did show CAD and LV dysfunction more frequently. Therefore, while sKlotho might be a marker for CVD in dialysis patients, the current data does not support a direct cardioprotective effect of sKlotho.

Background: Several investigators have reported discrepancies between the bromocresol-purple (BCP), bromocresol-green (BCG) and immunonephelometric (INP) assays in dialysis patients. This study compared the abovementioned assays and investigated whether hemodialysis itself or carbamylation of albumin is the cause for this discrepancy., Methods: Samples obtained from hemodialysis patients were analyzed by BCP, BCG and INP. Furthermore, albumin was carbamylated in vitro using isocyanate. Isocyanate converts lysine to homocitrulline., Results: No differences were observed between samples of the pre- and post-hemodialysis groups for BCP. In the control group, BCG averaged 6 g/L higher than INP. BCP did not statistically deviate from INP. In the dialysis group BCG averaged 5 g/L higher when compared to INP, whereas BCP averaged 2 g/L lower. BCP was affected by carbamylation of albumin. BCG and INP measurements were affected to a much lesser extent. Homocitrulline content of hydrolysates was increased in both the carbamylated albumin as well as in the dialysis population., Conclusion: In a hemodialysis population albumin concentrations are not consistently estimated by both BCG and BCP methods. Relative to INP measurements BCG overestimates the albumin concentration (4-10 g/L), whereas BCP leads to an underestimation (0-4 g/L). Carbamylation of albumin is the main attributor to the discrepancy found with BCP., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Introduction: The Early Warning Score (EWS) is used for early detection of deteriorating vital parameters and has been correlated with adverse outcomes. Unfortunately, neither its value on general wards nor the optimal cut-off value have been investigated. We aimed to find the optimal cut-off value for EWS on general wards, and investigated the possibility to raise this value from EWS ≥ 3 without compromising sensitivity too much., Methods: From May 2010 until May 2011, EWS was calculated from vital parameters in all patients in medical and surgical wards in the Medical Centre Alkmaar. Cut-off value was defined as EWS ≥ 3, unless otherwise specified. Six responses were defined and categorised as interventions (infusion prescription, medication changes, ICU consultation) and other actions (no action, change EWS cut-off value, oxygen supplementation), and it was registered whenever the threshold was exceeded., Results: 71,911 EWS values were obtained, 31,728 (44%) on medical wards and 40,183 (56%) on surgical wards. On medical wards, the cut-off value was exceeded 3734 times, and response was registered in 29% of the cases with 141 (12%) interventions. On surgical wards, the cut-off value was exceeded 3279 times, and response was registered in 19% of the cases with 633 (36%) interventions. Sensitivity and specificity for EWS ≥ 3 could not be calculated. For a calculated cut-off at EWS ≥ 4, sensitivity decreased to 74%., Conclusion: Raising the EWS threshold to 4 on general wards in the hospital would lead to an unacceptable decrease in sensitivity. Therefore, we recommend that the pre-defined cut-off should remain 3, with the possibility to personalise the threshold.

Background: Secondary hyperparathyroidism develops frequently with chronic kidney disease (CKD) and is associated with poor outcome. The new CKD-MBD guideline, Kidney Disease: Improving Global Outcomes (KDIGO), recommends a target range for PTH which is based on the locally used, upper reference range limit (URL). We examined the impact of the KDIGO guideline on the classification of dialysis patients in two different hospitals using 4 different intact-PTH assays., Methods: Blood samples from 76 consecutive hemodialysis CKD patients were measured for PTH concentration. Classification of the patients was performed according to the previous KDOQI and the KDIGO guideline using the manufacturers' and laboratory determined URLs. Classification of patients based on 3 different PTH methods (Siemens ADVIA Centaur, Siemens Immulite 2000, and Beckman Coulter Unicel DxI) was compared with the classification found in another hospital using the Roche Modular E170 PTH assay., Results: Depending on the PTH assay used, between 9 (12%) to 14 (18%) of the patients were classified differently in the two hospitals if the KDOQI guideline was followed. Application of the KDIGO-PTH target range resulted in a similar or decreased number of differently classified patients if the PTH concentration was measured using the Advia Centaur and Immulite assays. With the Beckman Coulter PTH assay, however, the number of differently KDIGO-classified patients increased if the manufacturers' URL (9.3 pmol/L) was used to calculate the PTH-target range. Application of the laboratory determined URL (7.0 pmol/L) improved concordance in classification, although the number of differently classified patients was still higher than with the other PTH assays. The best concordance in classification for the Beckman Coulter assay was found at a PTH value of 6.0 pmol/L. Regarding the Roche and Siemens assays, no significant difference was found in the classification using the URL either determined by the laboratory or the manufacturers., Conclusions: Compared with the KDOQI guideline, the new KDIGO guideline may increase the number of discrepancies in the classification of CKD patients if the Access Beckman Coulter PTH assay is used in conjunction with the calculated target range based on the manufacturers' URL. The best concordance in the classification for the Beckman Coulter assay was found at a PTH value below the manufacturers' and laboratory determined URL.

Objective: To identify factors influencing intention to consume an indigenous nutritious grain, fonio (Digitaria exilis), among women in Mali., Design: A cross-sectional questionnaire survey based on the Theory of Planned Behavior and the Health Belief Model., Setting and Participants: One hundred and eight women (31.5 ± 10.5 years), randomly selected by a 3-stage cluster sampling, Bamako, Mali., Main Outcome Measures: Model constructs scores, intention to consume fonio, and fonio consumption., Analysis: Correlation and multiple regression, Wilcoxon signed rank and Mann-Whitney tests for score comparison., Results: Attitudes toward behavior (β = .32, P < .05) was the best predictor of intention to consume fonio, which was significantly correlated with fonio consumption (rho = .78, P < .001). Health value (β = .23, P < .05) was a significant predictor of health behavior identity, which was significantly correlated with attitudes toward behavior (rho = .67, P < 0.001) and perceived barriers (rho = .33, P < .001). The latter formed a significant interaction term between intention and behavior (β = -.72, P < .05)., Conclusions and Implications: Fonio consumption could be increased in Bamako through stimulation of positive attitudes, changing men's beliefs, influencing family and neighbors' opinions, and improving the processing and the skills of women who prepare fonio., (Copyright © 2011 Society for Nutrition Education. Published by Elsevier Inc. All rights reserved.)

Mortality in dialysis patients is extremely high, with an annual death rate of approximately 23%. Sudden cardiac death (SCD) is the single largest cause of death in dialysis patients accounting for approximately 60% of all cardiac deaths and 25% of all-cause mortality. Interventions aiming at reducing cardiovascular mortality, especially SCD, in dialysis patients are therefore extremely important and clinically highly relevant. The purpose of this review is to give an outline of the epidemiology of SCD in dialysis patients and to provide a comprehensive overview of several interventional strategies (medical therapies, changing dialysis modality, and revascularization). Furthermore, it will discuss the current knowledge regarding the value of preventive implantable cardioverter defibrillator implantation and address future implications of the interventional strategies mentioned.

Objective: Sudden cardiac (arrhythmic) death (SCD) is the single largest cause of death in dialysis patients. Prophylactic Implantable Cardioverter Defibrillator (ICD) therapy reduces SCD and reduces all-cause mortality in several groups of patients at high risk for arrhythmic death. Whether this also applies to dialysis patients is unknown., Research Design and Methods: The Implantable Cardioverter Defibrillator in Dialysis patients (ICD2) trial is a prospective randomised controlled study. It has been designed to evaluate the efficacy and safety of prophylactic ICD therapy in reducing sudden cardiac death rates in dialysis patients aged 55-80 years. A total of 200 patients will be included. The primary endpoint of the study is sudden cardiac (arrhythmic) death. The mean follow-up time will be 4 years., Trial Registration: 'The Netherlands Trial Register'--ISRCTN20479861, Conclusion: The ICD2 trial--a pilot study--will be the first study to evaluate the possible benefit of ICD therapy for the primary prevention of sudden cardiac death in dialysis patients.

Statins can protect endothelial activation independent from their lipid-lowering effects. To gain more insight in mechanisms via which HMG-CoA inhibition may attenuate endothelial activation, we assessed the effects of mevastatin on eNOS expression of non- and modified-LDL treated endothelial cells and on basal and hydrogen peroxide-induced lipid peroxidation. Oxidized-LDL (Ox-LDL), but not glycated or acylated LDL decreased eNOS expression in human endothelial cells. The extent to which Ox-LDL decreases eNOS expression depends on the extent of modification of Ox-LDL. Mevastatin increased eNOS-expression, both in the presence and absence of Ox-LDL. In addition, mevastatin decreased the H(2)O(2)-induced (100 microM) lipid peroxidation in endothelial cells. This study shows that mevastatin has protective effects on endothelial cells by inducing eNOS and by inhibiting lipid peroxidation.

We describe the characterization of a new hemoglobin (Hb) variant found in a 77-year-old Dutch woman, suspected of hypoxia-mediated erythrocytosis. The typical blood parameters (Hb 17.3 g/dL; PCV 0.525 L/L; RBC 5.82 x 10(12)/L) could not be explained by any of the pathological or physiological conditions causing erythrocytosis. The patient was preventively phlebotomized because of intermittent claudication and erythrocytosis. At the hematological and biochemical levels, no anemia or hemolysis were present and no abnormal Hb fractions were detectable on alkaline electrophoresis or high performance liquid chromatography (HPLC). Molecular analysis revealed intact alpha-globin genes and a heterozygosity for a GTT-->GCT transition at codon 23 of the beta-globin gene, causing a Val-->Ala amino acid substitution. The P50 measured in full blood indicated that this mutant has an elevated oxygen affinity. This is the fourth single nucleotide substitution at codon 23 of the beta gene and the second associated with erythrocytosis. Because the family was not available for investigation no information was obtained as to whether the mutation represents a de novo event or was inherited, and might be a more common cause of erythrocytosis in Dutch patients. Considering the relatively high frequency of beta-thalassemia (thal) in the large allochthonous population in The Netherlands, combinations of Hb Zoeterwoude and beta-thal traits may lead to hemizygosity, with severe hypoxia and erythrocytosis from a few months after birth.

A 44-year-old female was found comatose after attempting suicide. Toxicological screening showed phenobarbital intoxication. The patient was treated symptomatically. After ten days her serum level of phenobarbital still had not decreased and she was not clinically recovered. The patient was transferred to another hospital for hemoperfusion to decrease the level of phenobarbital. After hemoperfusion the level of phenobarbital dropped significantly and the patient recovered neurologically. Phenobarbital has a long elimination half-life and for this reason it is advisable to use means to accelerate clearance until the clinical condition of the patient shows improvement. Multiple-dose activated charcoal effects the elimination of phenobarbital. If elimination needs to be speeded up, then hemoperfusion can be considered. If this technique is unavailable, hemodialysis is a good alternative.

Objective: In a combination of in vivo and in vitro studies, we investigated mechanisms via which alpha-tocopherol, a lipid soluble form of vitamin E, can directly affect endothelial activation as induced by H(2)O(2) and TNFalpha., Methods: We measured effects of alpha-tocopherol on H(2)O(2)-induced lipid peroxidation as determined with a fluorescent C-11 BODIPY(581/591) probe and on adhesion molecule expression in cultured endothelial cells. In 20 healthy volunteers treated with increasing doses of alpha-tocopherol up to 800 IU/ml for 12 weeks, plasma levels of soluble cell adhesion molecules (sCAMs) and C-reactive protein were measured., Results: We showed that alpha-tocopherol protects cultured endothelial cells against H(2)O(2)-induced lipid peroxidation, while TNFalpha did not induce lipid peroxidation. Moreover, alpha-tocopherol attenuated H(2)O(2)-, but not TNFalpha-induced increases in adhesion molecule expression. In healthy persons, alpha-tocopherol decreased plasma levels of sE-selectin from 65+/-6 to 60+/-6 ng/ml (P=0.002), sVCAM from 893+/-31 to 853+/-23 ng/ml (P=0.022), and sICAM from 483+/-21 to 463+/-16 ng/ml (P=0.048). C-Reactive protein, as a sensitive marker of low grade inflammation, was not significantly affected., Conclusion: alpha-Tocopherol specifically inhibits lipid peroxidation-induced endothelial activation in vitro. The observed vitamin E-induced decrease in sCAMs in control subjects suggests that lipid peroxidation can take place in healthy individuals. Although vitamin E supplementation may be especially effective in specific groups of patients exposed to increased oxidative stress, our study suggests that vitamin E supplementation can be of benefit in healthy individuals as well.

Nitric oxide (NO) may play an important role in the pathogenesis of diabetic microangiopathy. However, arteriolar changes in NO activity and sensitivity to NO may be dependent on both the type of arteriole and the duration of diabetes. Therefore, we assessed, in the in situ spinotrapezius muscle preparation of streptozotocin-diabetic rats and of controls, inside diameters of A2-A4 arterioles and the reactivity to topically applied acetylcholine and nitroprusside, before and after N(G)-nitro-L-arginine (L-NNA) at 2, 4, 6 and 12 weeks of diabetes. In A2 arterioles, basal diameters and the contribution of NO to basal diameter were not affected during the course of streptozotocin-induced diabetes. However, the maximal response to acetylcholine in these arterioles was attenuated after 2 until 4 weeks, and from 4 weeks on a sustained decrease in reactivity to sodium nitroprusside was observed. In A3 arterioles, both the basal diameter and the contribution of NO to basal diameter were decreased after 2 weeks and increased after 6 weeks, while the response to sodium nitroprusside was unaffected. In A4 arterioles, a significant increase in basal diameter was observed after 6 weeks only. Thus, this study shows that streptozotocin-induced diabetes causes microvascular changes in NO activity and sensitivity that depend on the type of arteriole. For each order of arteriole, these changes show a specific pattern during the course of diabetes.

Nitric oxide (NO) is involved in the regulation of SMC proliferation during intimal hyperplasia as has been shown by the inhibitory effect on intimal hyperplasia of adenovirus-mediated ceNOS overexpression in injured arteries in pig. Good assays to quantify the NO-producing enzymes, i.e., NO synthases (NOS), are essential to analyze the mechanism of action of NO in this process. We have developed novel flow cytometric assays for the simultaneous detection of NOS-3 protein, using NOS-3 specific antibodies, and NO production using 4,5-diaminofluorescein-diacetate (DAF-2/DA). The presence of NOS-3 protein and NO production is demonstrated on human A549 and HepG2 cells infected with a NOS-3 adenovirus (Ad.NOS-3). A comparative study showed that the flow cytometric assays are equally sensitive as Western blot analysis, the citrulline assay, or the Sievers assay. On human endothelial and SMC, NOS-3 protein and NO production were simultaneously detected with the assays, both under basal conditions and after Ad.NOS-3transduction. Simultaneous analysis of NOS-3 protein and NO production, made possible by the here-described novel flow cytometric assays, is of significant value to those investigating NOS-3 and NO., (Copyright 2001 Academic Press.)

Changes in NO activity may play an important role in the early increase in microvascular flow that has been implicated in the pathogenesis of diabetic microangiopathy. We assessed, in the in situ spinotrapezius muscle preparation of 6 weeks' streptozotocin-diabetic rats (n = 6) and of age-matched controls (n = 8), basal inside diameters of A2-A4 arterioles and the reactivity to topically applied acetylcholine and nitroprusside, before and after N(G)-nitro-L-arginine. In diabetic rats, cholinergic vasodilatation in A2-A4 arterioles was intact. Basal diameter in A3 and A4 arterioles was significantly higher in streptozotocin-diabetic rats. The increased basal diameter in A3 arterioles was partially due to an increased contribution of NO to basal diameter. The response to nitroprusside was impaired in streptozotocin-diabetic rats in A2, but not in A3 and A4 arterioles. Thus, this study shows that NO activity and sensitivity are altered after 6 weeks of streptozotocin-induced diabetes. These streptozotocin-induced changes are anatomically specific and, for arterioles, depend on their position within the vascular tree.

Isolated dystonia of trunk and neck muscles without involvement elsewhere has been termed segmental axial dystonia--a rare disorder. We report a 31-year-old man who developed marked dystonia of paraspinal muscles and progressive scoliosis 6 months after a closed head injury. Computed tomography (CT) disclosed three small areas of encephalomalacia, one involving the head of the caudate nucleus. Treatment with trihexyphenidyl resulted in significant improvement of the dystonia and scoliosis.

Cervical spondylotic myelopathy appears to result from a combination of factors. The two major components are 1) compressive forces resulting from narrowing of the spinal canal, and 2) dynamic forces owing to mobility of the cervical spine. There is substantial evidence to suggest that the repetitive trauma to the spinal cord that is sustained with movement in a spondylotic canal may be a major cause of progressive myelopathy. Utilization of extensive anterior procedures that remove the diseased ventral features as well as eliminate the dynamic forces owing to the accompanying fusion have grown in popularity. Cervical laminectomy enlarges the spinal canal, but does not reduce the dynamic forces affecting the spinal cord, and may actually increase cervical mobility, leading to a perpetuation of the myelopathy. The authors propose the combination of posterior decompression and Luque rectangle bone fusion to deal with both the compressive and the dynamic factors that lead to cervical spondylotic myelopathy. Ten patients who had advanced myelopathy underwent the combined procedures. Nine of the 10 experienced significant neurological improvement, and the 10th has had no progression. The combination of posterior decompression and Luque rectangle bone fusion may offer a simple, safe, and effective alternative treatment for cervical spondylotic myelopathy.