Assessment of GFR by four methods in adults in Ashanti, Ghana: the need for an eGFR equation for lean African populations

Background. Equations for estimating glomerular filtration rate (GFR) have not been validated in Sub-Saharan African populations, and data on GFR are few. Methods. GFR by creatinine clearance (Ccr) using 24-hour urine collections and estimated GFR (eGFR) using the four-variable Modification of Diet in Renal Disease (MDRD-4)[creatinine calibrated to isotope dilution mass spectrometry (IDMS) standard], Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) and Cockcroft–Gault equations were obtained in Ghanaians aged 40–75. The population comprised 1013 inhabitants in 12 villages; 944 provided a serum creatinine and two 24-hour urines. The mean weight was 54.4 kg; mean body mass index was 21.1 kg/m2. Results. Mean GFR by Ccr was 84.1 ml/min/1.73m2; 86.8% of participants had a GFR of 60 ml/min/1.73m2. Mean MDRD-4 eGFR was 102.3 ml/min/1.73m2 (difference vs. Ccr, 18.2: 95% CI: 16.8–19.5); when the factor for black race was omitted, the value (mean 84.6 ml/min/1.73m2) was close to Ccr. Mean CKD-EPI eGFR was 103.1 ml/min/1.73m2, and 89.4 ml/min/1.73m2 when the factor for race was omitted. The Cockcroft–Gault equation underestimated GFR compared with Ccr by 9.4 ml/min/1.73m2 (CI: 8.3–10.6); particularly in older age groups. GFR by Ccr, and eGFR by MDRD-4, CKD-EPI and Cockcroft–Gault showed falls with age: MDRD-4 5.5, Ccr 7.7, CKD-EPI 8.8 and Cockcroft–Gault 11.0 ml/min/1.73m2/10 years. The percentage of individuals identified with CKD stages 3–5 depended on the method used: MDRD-4 1.6% (7.2 % without factor for black race; CKD-EPI 1.7% (4.7% without factor for black race), Ccr 13.2% and Cockcroft–Gault 21.0%. Conclusions. Mean eGFR by both MDRD-4 and CKD-EPI was considerably higher than GFR by Ccr and Cockcroft–Gault, a difference that may be attributable to leanness. MDRD-4 appeared to underestimate the fall in GFR with age compared with the three other measurements; the fall with CKD-EPI without the adjustment for race was the closest to that of Ccr. An equation tailored specifically to the needs of the lean populations of Africa is urgently needed. For the present, the CKD-EPI equation without the adjustment for black race appears to be the most useful

Juvenile salmonid distribution, growth, condition, origin, and environmental and species associations in the Northern California Current

Information is summarized on juvenile salmonid distribution, size, condition, growth, stock origin, and species and environmental associations from June and August 2000 GLOBEC cruises with particular emphasis on differences related to the regions north and south of Cape Blanco off Southern Oregon. Juvenile salmon were more abundant during the August cruise as compared to the June cruise and were mainly distributed northward from Cape Blanco. There were distinct differences in distribution patterns between salmon species: chinook salmon were found close inshore in cooler water all along the coast and coho salmon were rarely found south of Cape Blanco. Distance offshore and temperature were the dominant explanatory variables related to coho and chinook salmon distribution. The nekton assemblages differed significantly between cruises. The June cruise was dominated by juvenile rockfishes, rex sole, and sablefish, which were almost completely absent in August. The forage fish community during June comprised Pacific herring and whitebait smelt north of Cape Blanco and surf smelt south of Cape Blanco. The fish community in August was dominated by Pacific sardines and highly migratory pelagic species. Estimated growth rates of juvenile coho salmon were higher in the GLOBEC study area than in areas farther north. An unusually high percentage of coho salmon in the study area were precocious males. Significant differences in growth and condition of juvenile coho salmon indicated different oceanographic environments north and south of Cape Blanco. The condition index was higher in juvenile coho salmon to the north but no significant differences were found for yearling chinook salmon. Genetic mixed stock analysis indicated that during June, most of the Chinook salmon in our sample originated from rivers along the central coast of Oregon. In August, chinook salmon sampled south of Cape Blanco were largely from southern Oregon and northern California; whereas most chinook salmon north of Cape Blanco were from the Central Valley in California

Gel transitions in colloidal suspensions

The idealized mode coupling theory (MCT) is applied to colloidal systems interacting via short-range attractive interactions of Yukawa form. At low temperatures MCT predicts a slowing down of the local dynamics and ergodicity breaking transitions. The nonergodicity transitions share many features with the colloidal gel transition, and are proposed to be the source of gelation in colloidal systems. Previous calculations of the phase diagram are complemented with additional data for shorter ranges of the attractive interaction, showing that the path of the nonergodicity transition line is then unimpeded by the gas-liquid critical curve at low temperatures. Particular attention is given to the critical nonergodicity parameters, motivated by recent experimental measurements. An asymptotic model is developed, valid for dilute systems of spheres interacting via strong short-range attractions, and is shown to capture all aspects of the low temperature MCT nonergodicity transitions.Comment: 12 pages, LaTeX, 5 eps figures, uses ioplppt.sty, to appear in J. Phys.: Condens. Matte

Clinical Management of Hyperkalemia

© 2020 Mayo Foundation for Medical Education and Research Hyperkalemia is an electrolyte abnormality with potentially life-threatening consequences. Despite various guidelines, no universally accepted consensus exists on best practices for hyperkalemia monitoring, with variations in precise potassium (K+) concentration thresholds or for the management of acute or chronic hyperkalemia. Based on the available evidence, this review identifies several critical issues and unmet needs with regard to the management of hyperkalemia. Real-world studies are needed for a better understanding of the prevalence of hyperkalemia outside the clinical trial setting. There is a need to improve effective management of hyperkalemia, including classification and K+ monitoring, when to reinitiate previously discontinued renin-angiotensin-aldosterone system inhibitor (RAASi) therapy, and when to use oral K+-binding agents. Monitoring serum K+ should be individualized; however, increased frequency of monitoring should be considered for patients with chronic kidney disease, diabetes, heart failure, or a history of hyperkalemia and for those receiving RAASi therapy. Recent clinical studies suggest that the newer K+ binders (patiromer sorbitex calcium and sodium zirconium cyclosilicate) may facilitate optimization of RAASi therapy. Enhancing the knowledge of primary care physicians and internists with respect to the safety profiles of these newer K+ binders may increase confidence in managing patients with hyperkalemia. Lastly, the availability of newer K+-binding agents requires further study to establish whether stringent dietary K+ restrictions are needed in patients receiving K+-binder therapy. Individualized monitoring of serum K+ among patients with an increased risk of hyperkalemia and the use of newer K+-binding agents may allow for optimization of RAASi therapy and more effective management of hyperkalemia

The Tea Bag Index—UK: using citizen/community science to investigate organic matter decomposition rates in domestic gardens

Gardening has the potential to influence several ecosystem services, including soil carbon dynamics, and shape progression towards the UN Sustainable Development Goals, (e.g., SDG 13). There are very few citizen/community science projects that have been set up to test an explicit hypothesis. However, citizen/community science allows collection of countrywide observations on ecosystem services in domestic gardens to inform us on the effects of gardening on SDGs. The geographical spread of samples that can be collected by citizen/community science would not be possible with a team of professional science researchers alone. Members of the general public across the UK submitted soil samples and buried standardised litter bags (tea bags) as part of the Tea Bag Index—UK citizen/community science project. Participants returned 511 samples from across the UK from areas in their garden where soil organic amendments were and were not applied. The project examined the effects of application of soil amendments on decomposition rates and stabilisation of litter, and in turn, effects on soil carbon and nitrogen concentrations. This was in response to a call for contributions to a global map of decomposition in the Teatime4Science campaign. Results suggested that application of amendments significantly increased decomposition rate and soil carbon, nitrogen, and carbon: nitrogen ratios within each garden. So much so that amendment application had more influence than geographic location. Furthermore, there were no significant interactions between location and amendment application. We therefore conclude that management in gardens has similar effects on soil carbon and decomposition, regardless of the location of the garden in question. Stabilisation factor was influenced more prominently by location than amendment application. Gardening management decisions can influence a number of SDGs and a citizen/community science project can aid in both the monitoring of SDGs, and involvement of the public in delivery of SDG

Hydraulic resistance to overland flow on surfaces with partially submerged vegetation

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/96239/1/wrcr13661.pd

Red Cells Genetically Deficient in Carbonic Anhydrase II Have Elevated Levels of a Carbonic Anhydrase Indistinguishable from Muscle CA III a

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/71425/1/j.1749-6632.1984.tb12351.x.pd

Abundance and local - scale processes contribute to multi-phyla gradients in global marine diversity

Among themost enduring ecological challenges is an integrated theory explaining the latitudinal biodiversity gradient, including discrepancies observed at different spatial scales. Analysis of Reef Life Survey data for 4127 marine species at 2406 coral and rocky sites worldwide confirms that the total ecoregion richness peaks in low latitudes, near +15°N and −15°S. However, although richness at survey sites ismaximal near the equator for vertebrates, it peaks at high latitudes for large mobile invertebrates. Site richness for different groups is dependent on abundance, which is in turn correlated with temperature for fishes and nutrients for macroinvertebrates. We suggest that temperature-mediated fish predation and herbivory have on strained mobile macroinvertebrate diversity at the site scale across the tropics. Conversely, at the ecoregion scale, richness responds positively to coral reef area, highlighting potentially huge global biodiversity losses with coral decline. Improved conservation outcomes require management frameworks, informed by hierarchical monitoring, that cover differing site- and regional-scale processes across diverse taxa, including attention to invertebrate species, which appear disproportionately threatened by warming seas

Cholinesterase inhibitor to prevent falls in Parkinson's disease (CHIEF-PD) trial:a phase 3 randomised, double-blind placebo-controlled trial of rivastigmine to prevent falls in Parkinson's disease

Abstract Background Falls are a common complication of Parkinson’s disease. There is a need for new therapeutic options to target this debilitating aspect of the disease. Cholinergic deficit has been shown to contribute to both gait and cognitive dysfunction seen in the condition. Potential benefits of using cholinesterase inhibitors were shown during a single centre phase 2 trial. The aim of this trial is to evaluate the effectiveness of a cholinesterase inhibitor on fall rate in people with idiopathic Parkinson’s disease. Methods This is a multi-centre, double-blind, randomised placebo-controlled trial in 600 people with idiopathic Parkinson’s disease (Hoehn and Yahr stages 1 to 4) with a history of a fall in the past year. Participants will be randomised to two groups, receiving either transdermal rivastigmine or identical placebo for 12 months. The primary outcome is the fall rate over 12 months follow-up. Secondary outcome measures, collected at baseline and 12 months either face-to-face or via remote video/telephone assessments, include gait and balance measures, neuropsychiatric indices, Parkinson’s motor and non-motor symptoms, quality of life and cost-effectiveness. Discussion This trial will establish whether cholinesterase inhibitor therapy is effective in preventing falls in Parkinson’s disease. If cost-effective, it will alter current management guidelines by offering a new therapeutic option in this high-risk population. Trial registration REC reference: 19/SW/0043. EudraCT: 2018–003219-23. ISCRTN: 41639809 (registered 16/04/2019). ClinicalTrials.gov Identifier: NCT04226248 Protocol at time of publication Version 7.0, 20th January 2021

ParkDB: a Parkinson's disease gene expression database

Parkinson's disease (PD) is a common, adult-onset, neuro-degenerative disorder characterized by the degeneration of cardinal motor signs mainly due to the loss of dopaminergic neurons in the substantia nigra. To date, researchers still have limited understanding of the key molecular events that provoke neurodegeneration in this disease. Here, we present ParkDB, the first queryable database dedicated to gene expression in PD. ParkDB contains a complete set of re-analyzed, curated and annotated microarray datasets. This resource enables scientists to identify and compare expression signatures involved in PD and dopaminergic neuron differentiation under different biological conditions and across species. Database URL: http://www2.cancer.ucl.ac.uk/Parkinson_Db2