Finite element approximation of the transport of reactive solutes in porous media .2. Error estimates for equilibrium adsorption processes

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Relationship of Homocysteine level and Comorbidities in VA Patients: A Retrospective Chart Review

Introduction: Elevated serum homocysteine is known to be associated with endothelial dysfunction, which is seen in multiple chronic diseases which include, but is not limited to Alzheimer’s, Dementia, and cardiovascular disease. This necessitated our investigation into serum homocysteine levels in VA patients and their associated comorbid disorders. Our study aimed to investigate comorbidities associated with elevated homocysteine levels, defined by being greater than 15 micromole/liter. Methods: Informatics at the VA was used to obtain a list of 654 patients with homocysteine drawn during the period of the study (7/21/2009 through 12/31/2013) at the John D. Dingell VAMC. Subjects were adults over 18 years of age. Patient gender, BMI, vitals, vitamin supplementation, and associated comorbidities were retrospectively analyzed and documented in an Excel file. The data from the excel file were statistically analyzed using SPSS 25. For each comorbidity and patient characteristic, homocysteine levels were compared using Independent Samples Mann-Whitney U test. Results: After completing statistical analysis of comorbidities commonly found in our Veteran population, those with statistically significant elevated levels (P-value \u3c0.05) of homocysteine were found to be Hypertension (P-value 0.001), Chronic Kidney Disease (P-value \u3c0.001), Dementia (P-value 0.004), Alzheimer’s (P-value 0.018), Peripheral Vascular Disease (P-value 0.046), and male gender (P-value 0.037). Of note, psoriasis was not statistically significant (P-value 0.855). Conclusion: Elevated homocysteine levels are known to be pro-inflammatory, which likely plays a role in their elevation in hypertension, chronic kidney disease, dementia, Alzheimer’s, and Peripheral Vascular Disease, necessitating a need to reduce homocysteine levels to improve patient outcomes

Dryland tree data for the Southwest region of Madagascar: alpha-level data can support policy decisions for conserving and restoring ecosystems of arid and semiarid regions

We present an eco-geographical dataset of the 355 tree species (1 56 genera, 55 families) found in the driest coastal portion of the spiny forest-thickets of southwestern Madagascar. This coastal strip harbors one of the richest and most endangered dryland tree floras in the world, both in terms of overall species diversity and of endemism. After describing the biophysical and socio-economic setting of this semiarid coastal region, we discuss this region’s diverse and rich tree flora in the context of the recent expansion of the protected area network in Madagascar and the growing engagement and commitment to ecological restoration. Our database, DTsMada (short for Desert Trees of Madagascar), is part of a larger ‘work-in-progress’, namely an eco-geographical database on desert and dryland trees of the world. DTsMada draws heavily on the Catalogue of the Vascular Plants of Madagascar (MadCat) project, in which floristic, ecological and endemism parameters are compiled, together with available conservation status assessments based on IUCN Red List criteria. Both are projects within the plant systematics database, Tropicos®, developed at Missouri Botanical Garden and maintained on the Garden’s website. To highlight the need for greater study of the interactions between biological, bioclimatic, and anthropogenic determinants of current and potentially changing biogeographical patterns and community dynamics in the tree strata of vegetation in the study area, we consider four contrasting groups of native trees: Adansonia spp. (Malvaceae), Pachypodium spp. (Apocynaceae), Baudouinia spp. (Fabaceae), and all 1 1 species in the 4 genera of Didiereaceae in Madagascar. We discuss DTsMada as a prototype dataset of alpha level information vital for effective conservation, landscape planning, sustainable use and management, and ecological restoration of degraded arid and semiarid ecosystems, in Madagascar and elsewhere. RÉSUMÉNous présentons un ensemble de données éco-géographiques sur les 355 espèces d’arbres (1 56 genres, 55 familles) présentes dans les fourrés et forêts épineux de la frange côtière aride et semiaride du Sud-ouest de Madagascar. Cette région possède un des assemblages d’arbres de climat sec les plus riches (en termes de diversité spécifique et d’endémisme), et les plus menacés au monde. Après une description du cadre biophysique et de la situation socio-économique de cette région, nous présentons cette flore régionale dans le contexte de la récente expansion du réseau de des aires protégées de Madagascar et de l’engagement croissant dans le domaine de la restauration écologique. Notre base de données DTsMada (raccourci de «d Desert Trees - Madagascar d », en anglais) s’inscrit dans le cadre d’une base de données éco-géographique plus large que nous développons, regroupant les espèces d’arbres des régions arides et semiarides du monde entier, avec un accent particulier mis sur leur utilisation dans la conservation, gestion et restauration écologique. Nombre des informations présentées dans DTsMada proviennent du projet MadCat (Catalogue des plantes vasculaires de Madagascar) qui regroupe des données floristiques et écologiques, et les statuts d’endémisme et de conservation des espèces végétales, basés sur les critères de l’UICN. Ces deux projets font partie de la base de données taxonomique Tropicos®, du Jardin Botanique du Missouri. Pour souligner le besoin de disposer de plus d’études pour comprendre d : les interactions entre les facteurs biologiques, bioclimatiques et anthropiques qui affectent la biogéographie et les dynamiques des communautés dans les strates arborées de la végétation dans la région étudiée, qu’il s’agisse de la situation actuelle ou celle d’un futur qui sera éventuellement modifié, nous considérons quatre groupes bien différents d’espèces d’arbres indigènesd : Adansonia spp. (Malvaceae), Pachypodium spp. (Apocynaceae), Baudouinia spp. (Fabaceae) et les 1 1 espèces dans les 4 genres de la famille des Didiereaceae du Sud-ouest de Madagascar. Nous traitons DTsMada comme prototype d’une base de données de niveau alpha, vitales pour la conservation, la planification, le développement durable, la gestion et la restauration écologique des écosystèmes arides et semiarides de Madagascar et d’ailleurs

A Single-Site Mutant and Revertants Arising in Vivo Define Early Steps in the Pathogenesis of Venezuelan Equine Encephalitis Virus

The early stages of Venezuelan equine encephalitis virus (VEE) pathogenesis in the mouse model have been examined using a genetic approach. Disease progression of a molecularly cloned single-site mutant was compared with that of the parental virus to determine the step in the VEE pathogenetic sequence at which the mutant was blocked. Assuming that such a block constitutes a genetic screen, isolates from different tissues thought to be distal to the block in the VEE pathogenetic sequence were analyzed to determine the pathogenetic step at which revertants of the mutant were selected. Directed mutation and analysis of reversion in vivo provide two powerful genetic tools for the dissection of the wild-type VEE pathogenetic sequence. Virus from the parental virulent clone, V3000, first replicated in the draining lymph node after subcutaneous inoculation in the left rear footpad. Movement of a cloned avirulent mutant, V3010 (E2 76 Glu to Lys), to the draining lymph node was impaired, replication in the node was delayed, and spread beyond the draining lymph node was sporadic. Serum, contralateral lymph node, spleen, and brain isolates from V3010 inoculated animals were invariably revertant with respect to sequence at E2 76 and/or virulence in mice. Revertants isolated from serum and contralateral lymph node retained the V3010 E2 Lys 76 mutation but also contained a second-site mutation, Glu to Lys at E2 116. Modification of the V3010 clone by addition of the second-site mutation at E2 116 produced a virus that bypassed the V3010 block at the draining lymph node but that did not possess full wild-type capacity for replication in the central nervous system or for induction of mortality. A control construct containing only the E2 116 reverting mutation on the V3000 background was identical to V3000 in terms of early pathogenetic steps and virulence. Therefore, analysis of mutant replication and reversion in vivo suggested (1) that the earliest steps in VEE pathogenesis are transit to the draining lymph node and replication at that site, (2) that the mutation in V3010 impairs transit to the draining lymph node and blocks dissemination to other tissues, and (3) that reversion can overcome the block without restoring full virulence

Regulation of the expression of the Cl-/anion exchanger pendrin in mouse kidney by acid-base status

Regulation of the expression of the Cl-/anion exchanger pendrin in mouse kidney by acid-base status.BackgroundPendrin belongs to a superfamily of Cl-/anion exchangers and is expressed in the inner ear, the thyroid gland, and the kidney. In humans, mutations in pendrin cause Pendred syndrome characterized by sensorineural deafness and goiter. Recently pendrin has been localized to the apical side of non-type A intercalated cells of the cortical collecting duct, and reduced bicarbonate secretion was demonstrated in a pendrin knockout mouse model. To investigate a possible role of pendrin in modulating acid-base transport in the cortical collecting duct, we examined the regulation of expression of pendrin by acid-base status in mouse kidney.MethodsMice were treated orally either with an acid or bicarbonate load (0.28 mol/L NH4Cl or NaHCO3) or received a K+-deficient diet for one week. Immunohistochemistry and Western blotting was performed.ResultsAcid-loading caused a reduction in pendrin protein expression levels within one day and decreased expression to 23% of control levels after one week. Concomitantly, pendrin protein was shifted from the apical membrane to the cytosol, and the relative abundance of pendrin positive cells declined. Similarly, in chronic K+-depletion, known to elicit a metabolic alkalosis, pendrin protein levels decreased and pendrin expression was shifted to an intracellular pool with the relative number of pendrin positive cells reduced. In contrast, following oral bicarbonate loading pendrin was found exclusively in the apical membrane and the relative number of pendrin positive cells increased.ConclusionsThese results are in agreement with a potential role of pendrin in bicarbonate secretion and regulation of acid-base transport in the cortical collecting duct

Anthropogenic ecosystem disturbance and the recovery debt

Ecosystem recovery from anthropogenic disturbances, either without human intervention or assisted by ecological restoration, is increasingly occurring worldwide. As ecosystems progress through recovery, it is important to estimate any resulting deficit in biodiversity and functions. Here we use data from 3,035 sampling plots worldwide, to quantify the interim reduction of biodiversity and functions occurring during the recovery process (that is, the 'recovery debt'). Compared with reference levels, recovering ecosystems run annual deficits of 46-51% for organism abundance, 27-33% for species diversity, 32-42% for carbon cycling and 31-41% for nitrogen cycling. Our results are consistent across biomes but not across degrading factors. Our results suggest that recovering and restored ecosystems have less abundance, diversity and cycling of carbon and nitrogen than 'undisturbed' ecosystems, and that even if complete recovery is reached, an interim recovery debt will accumulate. Under such circumstances, increasing the quantity of less-functional ecosystems through ecological restoration and offsetting are inadequate alternatives to ecosystem protection

Sodium/Hydrogen Exchanger Gene Defect in Slow-Wave Epilepsy Mutant Mice

AbstractThe “housekeeping” sodium/hydrogen exchanger, NHE1, mediates the electroneutral 1:1 exchange of Na+ and H+ across the plasma membrane. NHE1 is ubiquitous and is studied extensively for regulation of pH i, cell volume, and response to growth factors. We describe a spontaneous mouse mutant, s low-w ave e pilepsy, (swe), with a neurological syndrome including ataxia and a unique epilepsy phenotype consisting of 3/sec absence and tonic-clonic seizures. swe was fine-mapped on Chromosome 4 and identified as a null allele of Nhe1. Mutants show selective neuronal death in the cerebellum and brainstem but otherwise are healthy. This first example of a disease-causing mutation in an Nhe gene provides a new tool for studying the delicate balance of neuroexcitability and cell survival within the CNS