911 resultados para games in partition function form
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Abstract Background: Studies suggest that statins have pleiotropic effects, such as reduction in blood pressure, and improvement in endothelial function and vascular stiffness. Objective: To analyze if prior statin use influences the effect of renin-angiotensin-aldosterone system inhibitors on blood pressure, endothelial function, and vascular stiffness. Methods: Patients with diabetes and hypertension with office systolic blood pressure ≥ 130 mmHg and/or diastolic blood pressure ≥ 80 mmHg had their antihypertensive medications replaced by amlodipine during 6 weeks. They were then randomized to either benazepril or losartan for 12 additional weeks while continuing on amlodipine. Blood pressure (assessed with ambulatory blood pressure monitoring), endothelial function (brachial artery flow-mediated dilation), and vascular stiffness (pulse wave velocity) were evaluated before and after the combined treatment. In this study, a post hoc analysis was performed to compare patients who were or were not on statins (SU and NSU groups, respectively). Results: The SU group presented a greater reduction in the 24-hour systolic blood pressure (from 134 to 122 mmHg, p = 0.007), and in the brachial artery flow-mediated dilation (from 6.5 to 10.9%, p = 0.003) when compared with the NSU group (from 137 to 128 mmHg, p = 0.362, and from 7.5 to 8.3%, p = 0.820). There was no statistically significant difference in pulse wave velocity (SU group: from 9.95 to 9.90 m/s, p = 0.650; NSU group: from 10.65 to 11.05 m/s, p = 0.586). Conclusion: Combined use of statins, amlodipine, and renin-angiotensin-aldosterone system inhibitors improves the antihypertensive response and endothelial function in patients with hypertension and diabetes.
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Sulfur (S) is an essential macronutrient for all living organisms. Plants require large amounts of sulfate for growth and development, and this serves as a major entry point of sulfate into the food web. Plants acquire S in its ionic form from the soil; they have evolved tightly controlled mechanisms for the regulation of sulfate uptake in response to its external and internal availability. In the model plant Arabidopsis thaliana, the first key step in sulfate uptake is presumed to be carried out exclusively by only two high-affinity sulfate transporters: SULTR1;1 and SULTR1;2. A better understanding of the mode of regulation for these two transporters is crucial because they constitute the first determinative step in balancing sulfate in respect to its supply and demand. Here, we review the recent progress achieved in our comprehension of (i) mechanisms that regulate these two high-affinity sulfate transporters at the transcriptional and post-transcriptional levels, and (ii) their structure-function relationship. Such progress is important to enable biotechnological and agronomic strategies aimed at enhancing sulfate uptake and improving crop yield in S-deficient soils.
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The alpha1b-adrenergic receptor (AR) is a member of the large superfamily of seven transmembrane domain (TMD) G protein-coupled receptors (GPCR). Combining site-directed mutagenesis of the alpha1b-AR with computational simulations of receptor dynamics, we have explored the conformational changes underlying the process of receptor activation, i.e. the transition between the inactive and active states. Our findings suggest that the structural constraint stabilizing the alpha1b-AR in the inactive form is a network of H-bonding interactions amongst conserved residues forming a polar pocket and R143 of the DRY sequence at the end of TMDIII. We have recently reported that point mutations of D142, of the DRY sequence and of A293 in the distal portion of the third intracellular loop resulted in ligand-independent (constitutive) activation of the alpha1b-AR. These constitutively activating mutations could induce perturbations resulting in the shift of R143 out of the polar pocket. The main role of R143 may be to mediate receptor activation by triggering the exposure of several basic amino acids of the intracellular loops towards the G protein. Our investigation has been extended also to the biochemical events involved in the desensitization process of alpha1b-AR. Our results indicate that immediately following agonist-induced activation, the alpha1b-AR can undergo rapid agonist-induced phosphorylation and desensitization. Different members of the G protein coupled receptor kinase family can play a role in agonist-induced regulation of the alpha1b-AR. In addition, constitutively active alpha1b-AR mutants display different phosphorylation and internalization features. The future goal is to further elucidate the molecular mechanism underlying the complex equilibrium between activation and inactivation of the alpha1b-AR and its regulation by pharmacological substances. These findings can help to elucidate the mechanism of action of various agents displaying properties of agonists or inverse agonists at the adrenergic system.
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Merozoite surface protein-1 (MSP-1, also referred to as P195, PMMSA or MSA 1) is one of the most studied of all malaria proteins. The proteins. The protein is found in all malaria species investigated and structural studies on the gene indicate that parts of the molecule are well-conserved. Studies on Plasmodium falciparum have shown that the protein is in a processed form on the merozoite surface, a result of proteolytic cleavage of the large percursor molecule. Recent studies have identified some of these cleavage sites. During invasion of the new red cell most of the MSP1 molecule is shed from the parasite surface except for a small C-terminal fragment which can be detected in ring stages. Analysis of the structure of this fragment suggests that it contains two growth factor-like domains that may have a functional role.
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Background: The RCP is a 14 French collapsable percutaneous cardiovascular support device positioned in the descending part of the thoracic aorta via the femoral artery. A 10 patient first in man study demonstrated device safety and significant improvement in renal function among high risk PCI patients. We now report haemodynamic and renal efficacy in patients with ADHF.Methods: Prospective non randomised study seeking to recruit 20 patients with ADHF with a need for inotropic or mechanical circulatory support with: i) EF < 30% ii)Cardiac index(CI) < 2.2 L / min / m2 Outcome measures included: 1) Cardiac index (CI) 2) Pulmonary Capillary Wedge Pressure (PCWP) 3) Urine output / serum creatinine 4) Vascular / device complications 5) 30 day mortalityResults: INTERIM ANALYSIS (n=12) The mean age of the study group was 64 years, with a mean baseline creatinine of 193 umol/L, eGFR 38 ml/min. The intended RCP treatment period was 24 hours. During RCP treatment there was a significant mean reduction of PCWP at 4 hours of 17% (25 to 21 mmHg p=0.04). Mean CI increased at 12 hours by 11%, though not reaching significance (1.78 to 1.96 L/min/m2 p=0.08). RCP insertion prompted substantial diuresis. Urine output tripled over the first 12 hours compared to baseline (55 ml/hr vs 213 ml/hr p=0.03). This was associated with significantly improved renal function, a 28% reduction in serum creatinine at 12 hours (193 to 151 umol/L p=0.003), and a increase in eGFR from 38 ml/min to 50 ml/min (p=0.0007). 2 patients previously refused cardiac transplantation were reassessed and successfully transplanted within 9 months of RCP treatment on the basis of demonstrable renal reversibility. There were no vascular or device complications. There were 2 deaths at 30 days, one from multi-organ failure and sepsis, and one from intractable heart failure - neither were device related.Conclusion: RCP support in ADHF patients was associated with improved haemodynamics, and an improvement in renal function. The Reitan Catheter Pump may have a role in providing percutaneous cardiovascular and renal support in the acutely decompensated cardiac patient, and may have a role in suggesting renal reversibility in potential cardiac transplant patients. Further data will be reported at recruitment completion.
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Physical activity is beneficial for healthy ageing. It may also help maintain good cognitive function in older age. Aerobic activity improves cardiovascular fitness, but it is not known whether this sort of fitness is necessary for improved cognitive function.��Eleven studies of aerobic physical activity programmes for healthy people over the age of 55 years have been included in this review. Eight of these 11 studies reported that aerobic exercise interventions resulted in increased fitness of the trained group and an improvement in at least one aspect of cognitive function. The largest effects were on cognitive speed, auditory and visual attention. However, the cognitive functions which improved were not the same in each study and the majority of comparisons yielded no significant results.��The data are insufficient to show that the improvements in cognitive function which can be attributed to physical exercise are due to improvements in cardiovascular fitness.
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In vascular plants, the best-known feature of a differentiated endodermal cell is the "Casparian Strip" (CS). This structure refers to a highly localized cell wall impregnation in the transversal and anticlinal walls of the cell, which surrounds the cell like a belt/ring and is tightly coordinated with respect to neighboring cells. Analogous to tight junctions in animal epithelia, CS in plants act as a diffusion barrier that controls the movement of water and ions from soil into the stele. Since its first description by Robert Caspary in 1865 there have been many attempts to identify the chemical nature of the cell wall deposition in CS. Suberin, lignin, or both have been claimed to be the important components of CS in a series of different species. However, the exact chemical composition of CS has remained enigmatic. This controversy was due to the confusion and lack of knowledge regarding the precise measurement of three developmental stages of the endodermis. The CS represent only the primary stage of endodermal differentiation, which is followed by the deposition of suberin lamellae all around the cellular surface of endodermal cells (secondary developmental stage). Therefore, chemical analysis of whole roots, or even of isolated endodermal tissues, will always find both of the polymers present. It was crucial to clarify this point because this will guide our efforts to understand which cell wall biosynthetic component becomes localized in order to form the CS. The main aim of my work was to find out the major components of (early) CS, as well as their spatial and temporal development, physiological roles and relationship to barrier formation. Employing the knowledge and tools that have been accumulated over the last few years in the model plant Arabidopsis thaliana, various histological and chemical assays were used in this study. A particular feature of my work was to completely degrade, or inhibit formation of lignin and suberin biopolymers by biochemical, classical genetic and molecular approaches and to investigate its effect on CS formation and the establishment of a functional diffusion barrier. Strikingly, interference with monolignol biosynthesis abrogates CS formation and delays the formation of function diffusion barrier. In contrast, transgenic plants devoid of any detectable suberin still develop a functional CS. The combination of all these assays clearly demonstrates that the early CS polymer is made from monolignol (lignin monomers) and is composed of lignin. By contrast, suberin is formed much later as a secondary wall during development of endodermis. These early CS are functionally sufficient to block extracellular diffusion and suberin does not play important role in the establishment of early endodermal diffusion barrier. Moreover, suberin biosynthetic machinery is not present at the time of CS formation. Our study finally concludes the long-standing debate about the chemical nature of CS and opens the door to a new approach in lignin research, specifically for the identification of the components of the CS biosynthetic pathway that mediates the localized deposition of cell walls. I also made some efforts to understand the patterning and differentiation of endodermal passage cells in young roots. In the literature, passage cells are defined as a non- suberized xylem pole associated endodermal cells. Since these cells only contain the CS but not the suberin lamellae, it has been assumed that these cells may offer a continued low-resistance pathway for water and minerals into the stele. Thus far, no genes have been found to be expressed specifically in passage cells. In order to understand the patterning, differentiation, and physiological role of passage it would be crucial to identify some genes that are exclusively expressed in these cells. In order to identify such genes, I first generated fluorescent marker lines of stele-expressed transporters that have been reported to be expressed in the passage cells. My aim was to first highlight the passage cells in a non-specific way. In order to find passage cell specific genes I then adapted a two-component system based on previously published methods for gene expression profiling of individual cell types. This approach will allow us to target only the passage cells and then to study gene expression specifically in this cell type. Taken together, this preparatory work will provide an entry point to understand the formation and role of endodermal passage cells. - Chez les plantes vasculaires, la caractéristique la plus commune des cellules différentiées de l'endoderme est la présence de cadres de Caspary. Cette structure correspond à une imprégnation localisée des parties transversales et anticlinales de la paroi cellulaire. Cela donne naissance, autour de la cellule, à un anneau/cadre qui est coordonné par rapport aux cellules voisines. De manière analogue aux jonctions serrées des épithéliums chez les animaux, les cadres de Caspary agissent chez les plantes comme barrière de diffusion, contrôlant le mouvement de l'eau et des ions à travers la racine entre le sol et la stèle. Depuis leur première description par Robert Caspary en 1865, beaucoup de tentatives ont eu pour but de définir la nature chimique de ces cadres de Caspary. Après l'étude de différentes espèces végétales, à la fois la subérine, la lignine ou les deux ont été revendiquées comme étant des composants importants de ces cadres. Malgré tout, leur nature chimique exacte est restée longtemps énigmatique. Cette controverse provient de la confusion et du manque de connaissance concernant la détermination précise des trois stades de développement de l'endoderme. Les cadres de Caspary représentent uniquement le stade primaire de différentiation de l'endoderme. Celui-ci est suivi par le second stade de différentiation, la déposition de lamelles de subérine tout autour de la cellule endodermal. De ce fait, l'analyse chimique de racines entières ou de cellules d'endoderme isolées ne permet pas de séparer les stades de différentiation primaire et secondaire et aboutit donc à la présence des deux polymères. Il est également crucial de clarifier ce point dans le but de connaître quelle machinerie cellulaire localisée à la paroi cellulaire permet l'élaboration des cadres de Caspary. En utilisant les connaissances et les outils accumulés récemment grâce à la plante modèle Arabidopsis thaliana, divers techniques histologiques et chimiques ont été utilisées dans cette étude. Un point particulier de mon travail a été de dégrader ou d'inhiber complètement la formation de lignine ou de subérine en utilisant des approches de génétique classique ou moléculaire. Le but étant d'observer l'effet de l'absence d'un de ces deux polymères sur la formation des cadres de Caspary et l'établissement d'une barrière de diffusion fonctionnelle. De manière frappante, le fait d'interférer avec la voie de biosynthèse de monolignol (monomères de lignine) abolit la formation des cadres de Caspary et retarde l'élaboration d'une barrière de diffusion fonctionnelle. Par contre, des plantes transgéniques dépourvues d'une quantité détectable de subérine sont quant à elles toujours capables de développer des cadres de Caspary fonctionnels. Mises en commun, ces expériences démontrent que le polymère formant les cadres de Caspary dans la partie jeune de la racine est fait de monolignol, et que de ce fait il s'agit de lignine. La subérine, quant à elle, est formée bien plus tard durant le développement de l'endoderme, de plus il s'agit d'une modification de la paroi secondaire. Ces cadres de Caspary précoces faits de lignine suffisent donc à bloquer la diffusion extracellulaire, contrairement à la subérine. De plus, la machinerie de biosynthèse de la subérine n'est pas encore présente au moment de la formation des cadres de Caspary. Notre étude permet donc de mettre un terme au long débat concernant la nature chimique des cadres de Caspary. De plus, elle ouvre la porte à de nouvelles approches dans la recherche sur la lignine, plus particulièrement pour identifier des composants permettant la déposition localisée de ce polymère dans la paroi cellulaire. J'ai aussi fais des efforts pour mettre en évidence la formation ainsi que le rôle des cellules de passage dans les jeunes racines. Dans la littérature, les cellules de passage sont définies comme de la cellule endodermal faisant face aux pôles xylèmes et dont la paroi n'est pas subérisée. Du fait que ces cellules contiennent uniquement des cadres de Caspary et pas de lamelle de subérine, il a été supposé qu'elles ne devraient offrir que peu de résistance au passage de l'eau et des nutriments entre le sol et la stèle. Le rôle de ces cellules de passage est toujours loin d'être clair, de plus aucun gène s'exprimant spécifiquement dans ces cellules n'a été découvert à ce jour. De manière à identifier de tels gènes, j'ai tout d'abord généré des marqueurs fluorescents pour des transporteurs exprimés dans la stèle mais dont l'expression avait également été signalée dans l'endoderme, uniquement dans les cellules de passage. J'ai ensuite développé un système à deux composants basé sur des méthodes déjà publiées, visant principalement à étudier le profil d'expression génique dans un type cellulaire donné. En recoupant les gènes exprimés spécifiquement dans l'endoderme à ceux exprimés dans la stèle et les cellules de passage, il nous sera possible d'identifier le transriptome spécifique de ces cellules. Pris dans leur ensemble, ces résultats devraient donner un bon point d'entrée dans la définition et la compréhension des cellules de passage.
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Often dismissed as "not serious," the notion of play has nevertheless been at the center of classical theories of religion and ritual (Huizinga, Caillois, Turner, Staal, etc.). What can be retained of these theories for the contemporary study of religions? Can a study of "play" or "game" bring new perspectives for the study of religions? The book deals with the history of games and their relation to religions, the links between divination and games, the relations between sport and ritual, the pedagogical functions of games in religious education, and the interaction between games, media and religions. Richly illustrated, the book contributes to the study of religions, to ritual, game and media studies, and addresses an academic as well as a general public.
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BACKGROUND: Decreasing exposure to airborne particulates was previously associated with reduced age-related decline in lung function. However, whether the benefit from improved air quality depends on genetic background is not known. Recent evidence points to the involvement of the genes p53 and p21 and of the cell cycle control gene cyclin D1 (CCND1) in the response of bronchial cells to air pollution. OBJECTIVE: We determined in 4,326 participants of the Swiss Cohort Study on Air Pollution and Lung and Heart Diseases in Adults (SAPALDIA) whether four single-nucleotide polymorphisms in three genes [CCND1 (rs9344 [P242P], rs667515), p53 (rs1042522 [R72P]), and p21 (rs1801270 [S31R])] modified the previously observed attenuation of the decline in the forced expiratory flow between 25% and 75% of the forced vital capacity (FEF(25-75)) associated with improved air quality. METHODS: Subjects of the prospective population-based SAPALDIA cohort were assessed in 1991 and 2002 by spirometry, questionnaires, and biological sample collection for genotyping. We assigned spatially resolved concentrations of particulate matter with aerodynamic diameter < or = 10 microm (PM(10)) to each participant's residential history 12 months before the baseline and follow-up assessments. RESULTS: The effect of diminishing PM(10) exposure on FEF(25-75) decline appeared to be modified by p53 R72P, CCND1 P242P, and CCND1 rs667515. For example, a 10-microg/m(3) decline in average PM(10) exposure over an 11-year period attenuated the average annual decline in FEF(25-75) by 21.33 mL/year (95% confidence interval, 10.57-32.08) among participants homozygous for the CCND1 (P242P) GG genotype, by 13.72 mL/year (5.38-22.06) among GA genotypes, and by 6.00 mL/year (-4.54 to 16.54) among AA genotypes. CONCLUSIONS: Our results suggest that cell cycle control genes may modify the degree to which improved air quality may benefit respiratory function in adults.
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A pseudogene, designated as "ps(5.8S+ITS-2)", paralogous to the 5.8S gene and internal transcribed spacer (ITS)-2 of the nuclear ribosomal DNA (rDNA), has been recently found in many triatomine species distributed throughout North America, Central America and northern South America. Among characteristics used as criteria for pseudogene verification, secondary structures and free energy are highlighted, showing a lower fit between minimum free energy, partition function and centroid structures, although in given cases the fit only appeared to be slightly lower. The unique characteristics of "ps(5.8S+ITS-2)" as a processed or retrotransposed pseudogenic unit of the ghost type are reviewed, with emphasis on its potential functionality compared to the functionality of genes and spacers of the normal rDNA operon. Besides the technical problem of the risk for erroneous sequence results, the usefulness of "ps(5.8S+ITS-2)" for specimen classification, phylogenetic analyses and systematic/taxonomic studies should be highlighted, based on consistence and retention index values, which in pseudogenic sequence trees were higher than in functional sequence trees. Additionally, intraindividual, interpopulational and interspecific differences in pseudogene amount and the fact that it is a pseudogene in the nuclear rDNA suggests a potential relationships with fitness, behaviour and adaptability of triatomine vectors and consequently its potential utility in Chagas disease epidemiology and control.
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Through their capacity to sense danger signals and to generate active interleukin-1β (IL-1β), inflammasomes occupy a central role in the inflammatory response. In contrast to IL-1β, little is known about how IL-1α is regulated. We found that all inflammasome activators also induced the secretion of IL-1α, leading to the cosecretion of both IL-1 cytokines. Depending on the type of inflammasome activator, release of IL-1α was inflammasome dependent or independent. Calcium influx induced by the opening of cation channels was sufficient for the inflammasome-independent IL-1α secretion. In both cases, IL-1α was released primarily in a processed form, resulting from intracellular cleavage by calpain-like proteases. Inflammasome-caspase-1-dependent release of IL-1α and IL-1β was independent of caspase-1 catalytic activity, defining a mode of action for caspase-1. Because inflammasomes contribute to the pathology of numerous chronic inflammatory diseases such as gout and diabetes, IL-1α antagonists may be beneficial in the treatment of these disorders.
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Bordetella pertussis is the bacterial agent of whooping cough in humans. Under iron-limiting conditions, it produces the siderophore alcaligin. Released to the extracellular environment, alcaligin chelates iron, which is then taken up as a ferric alcaligin complex via the FauA outer membrane transporter. FauA belongs to a family of TonB-dependent outer membrane transporters that function using energy derived from the proton motive force. Using an in-house protocol for membrane-protein expression, purification and crystallization, FauA was crystallized in its apo form together with three other TonB-dependent transporters from different organisms. Here, the protocol used to study FauA is described and its three-dimensional structure determined at 2.3 A resolution is discussed.
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INTRODUCTION: The influence of specific health problems on health-related quality of life (HRQoL) in childhood cancer survivors is unknown. We compared HRQoL between survivors of childhood cancer and their siblings, determined factors associated with HRQoL, and investigated the influence of chronic health problems on HRQoL. METHODS: Within the Swiss Childhood Cancer Survivor Study, we sent a questionnaire to all survivors (≥16 years) registered in the Swiss Childhood Cancer Registry, who survived >5 years and were diagnosed 1976-2005 aged <16 years. Siblings received similar questionnaires. We assessed HRQoL using Short Form-36 (SF-36). Health problems from a standard questionnaire were classified into overweight, vision impairment, hearing, memory, digestive, musculoskeletal or neurological, and thyroid problems. RESULTS: The sample included 1,593 survivors and 695 siblings. Survivors scored significantly lower than siblings in physical function, role limitation, general health, and the Physical Component Summary (PCS). Lower score in PCS was associated with a diagnosis of central nervous system tumor, retinoblastoma or bone tumor, having had surgery, cranio-spinal irradiation, or bone marrow transplantation. Lower score in Mental Component Summary was associated with older age. All health problems decreased HRQoL in all scales. Most affected were survivors reporting memory problems and musculoskeletal or neurological problems. Health problems had the biggest impact on physical functioning, general health, and energy and vitality. CONCLUSIONS: In this study, we showed the negative impact of specific chronic health problems on survivors' HRQoL. IMPLICATIONS FOR CANCER SURVIVORS: Therapeutic preventive measures, risk-targeted follow-up, and interventions might help decrease health problems and, consequently, improve survivors' quality of life.
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Because an individual's investment into the immune system may modify its dispersal rate, immune function may evolve rapidly in an invader. We collected cane toads (Rhinella marina) from sites spanning their 75-year invasion history in Australia, bred them, and raised their progeny in standard conditions. Evolved shifts in immune function should manifest as differences in immune responses among the progeny of parents collected in different locations. Parental location did not affect the offspring's cell-mediated immune response or stress response, but blood from the offspring of invasion-front toads had more neutrophils, and was more effective at phagocytosis and killing bacteria. These latter measures of immune function are negatively correlated with rate of dispersal in free-ranging toads. Our results suggest that the invasion of tropical Australia by cane toads has resulted in rapid genetically based compensatory shifts in the aspects of immune responses that are most compromised by the rigours of long-distance dispersal.
PLEKHG5 deficiency leads to an intermediate form of autosomal-recessive Charcot-Marie-Tooth disease.
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Charcot-Marie-Tooth disease (CMT) comprises a clinically and genetically heterogeneous group of peripheral neuropathies characterized by progressive distal muscle weakness and atrophy, foot deformities and distal sensory loss. Following the analysis of two consanguineous families affected by a medium to late-onset recessive form of intermediate CMT, we identified overlapping regions of homozygosity on chromosome 1p36 with a combined maximum LOD score of 5.4. Molecular investigation of the genes from this region allowed identification of two homozygous mutations in PLEKHG5 that produce premature stop codons and are predicted to result in functional null alleles. Analysis of Plekhg5 in the mouse revealed that this gene is expressed in neurons and glial cells of the peripheral nervous system, and that knockout mice display reduced nerve conduction velocities that are comparable with those of affected individuals from both families. Interestingly, a homozygous PLEKHG5 missense mutation was previously reported in a recessive form of severe childhood onset lower motor neuron disease (LMND) leading to loss of the ability to walk and need for respiratory assistance. Together, these observations indicate that different mutations in PLEKHG5 lead to clinically diverse outcomes (intermediate CMT or LMND) affecting the function of neurons and glial cells.