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The blood-brain barrier (BBB) is an extensive capillary network that protects the brain from environmental and metabolic toxins while limiting drug delivery to the central nervous system (CNS). The ATP-binding cassette transporter breast cancer resistance protein (Bcrp) reduces drug delivery across the BBB by actively transporting its clinical substrates back into peripheral circulation before their entry into the CNS compartment. 17ß-Estradiol (E2)-elicited changes in Bcrp transport activity and expression have been documented previously. We report a novel signaling mechanism by which E2 decreases Bcrp transport activity in mouse brain capillaries via rapid nongenomic signaling through estrogen receptor α. We extended this finding to investigate the effects of different endocrine-disrupting compounds (EDCs) and selective estrogen receptor modulators (SERMs) on Bcrp transport function. We also demonstrate sex-dependent expression of Bcrp and E2-sensitive Bcrp transport activity at the BBB ex vivo. This work establishes an explanted tissue-based model by which to interrogate EDCs and SERMs as modulators of nongenomic estrogenic signaling with implications for sex and hormonal regulation of therapeutic delivery into the CNS.
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Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 2 , Barrera Hematoencefálica , Estradiol , Receptor alfa de Estrógeno , Transducción de Señal , Animales , Barrera Hematoencefálica/metabolismo , Barrera Hematoencefálica/efectos de los fármacos , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 2/metabolismo , Receptor alfa de Estrógeno/metabolismo , Ratones , Femenino , Transducción de Señal/efectos de los fármacos , Estradiol/farmacología , Masculino , Transporte Biológico/efectos de los fármacos , Ratones Endogámicos C57BLRESUMEN
Pioneering statistician and father of information geometry.
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Several mouse models have been developed to study polycystic ovarian syndrome (PCOS), a leading cause of infertility in women. Treatment of mice with DHT for 90 days causes ovarian and metabolic phenotypes similar to women with PCOS. We used this 90-day DHT treatment paradigm to investigate the variable incidence and heterogeneity in 2 inbred mouse strains, NOD/ShiLtJ and 129S1/SvlmJ. NOD mice naturally develop type 1 diabetes, and recent meta-analysis found increased androgen excess and PCOS in women with type 1 diabetes. The 129S1 mice are commonly used in genetic manipulations. Both NOD and 129S1 DHT-treated mice had early vaginal opening, increased anogenital distance, and altered estrus cycles compared with control animals. Additionally, both NOD and 129S1 mice had reduced numbers of corpora lutea after DHT exposure, whereas NOD mice had decreased numbers of preantral follicles and 129S1 mice had reduced numbers of small antral follicles. NOD mice had increased body weight, decreased white adipocyte size, and improved glucose sensitivity in response to DHT, whereas 129S1 mice had increased body weight and white adipocyte size. NOD mice had increased expression of Adiponectin, Cidea, Srebp1a, and Srebp1b and 129S1 mice had decreased Pparg in the white adipose tissues, whereas both NOD and 129S1 mice had increased expression of Glut4 and Prdm16, suggesting DHT may differentially affect glucose transport, thermogenesis, and lipid storage in white adipose tissue. DHT causes different ovarian and metabolic responses in NOD and 129S1 mice, suggesting that strain differences may allow further elucidation of genetic contributions to PCOS.
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Diabetes Mellitus Tipo 1 , Síndrome del Ovario Poliquístico , Humanos , Femenino , Ratones , Animales , Síndrome del Ovario Poliquístico/metabolismo , Diabetes Mellitus Tipo 1/complicaciones , Ratones Endogámicos NOD , Modelos Animales de Enfermedad , Peso Corporal/fisiología , DihidrotestosteronaRESUMEN
Background: It has been postulated that musicianship can lead to enhanced brain and cognitive reserve, but the neural mechanisms of this effect have been poorly understood. Lifelong professional musicianship in conjunction with novel brain imaging techniques offers a unique opportunity to examine brain network differences between musicians and matched controls. Objective: In this study we aim to investigate how resting-state functional networks (FNs) manifest in lifelong active musicians. We will evaluate the FNs of lifelong musicians and matched healthy controls using resting-state functional magnetic resonance imaging. Methods: We derive FNs using the data-driven independent component analysis approach and analyze the functional network connectivity (FNC) between the default mode (DMN), sensory-motor (SMN), visual (VSN), and auditory (AUN) networks. We examine whether the linear regressions between FNC and age are different between the musicians and the control group. Results: The age trajectory of average FNC across all six pairs of FNs shows significant differences between musicians and controls. Musicians show an increase in average FNC with age while controls show a decrease (P = 0.013). When we evaluated each pair of FN, we note that in musicians FNC values increased with age in DMN-AUN, DMN-VSN, and SMN-VSN and in controls FNC values decreased with age in DMN-AUN, DMN-SMN, AUN-SMN, and SMN-VSN. Conclusion: This result provides early evidence that lifelong musicianship may contribute to enhanced brain and cognitive reserve. Results of this study are preliminary and need to be replicated with a larger number of participants.
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Objective: To describe optical coherence tomography (SD-OCT) features, age, gender, and systemic variables that may be used in machine/deep learning studies to identify high-risk patient subpopulations with high risk of progression to geographic atrophy (GA) and visual acuity (VA) loss in the short term. Design: prospective, longitudinal study. Subjects: We analyzed imaging data from patients with iAMD (N= 316) enrolled in Age-Related Eye Disease Study 2 (AREDS2) Ancillary SD-OCT with adequate SD-OCT imaging for repeated measures. Methods: Qualitative and quantitative multimodal variables from the database were derived at each yearly visit over 5 years. Based on statistical analyses developed in the field of cardiology, an algorithm was developed and used to select person-years without GA on colour fundus photography or SD-OCT at baseline. The analysis employed machine learning approaches to generate classification trees. Eyes were stratified as low, average, above average and high risk in 1 or 2 years, based on OCT and demographic features by the risk of GA development or decreased VA by 5+ and 10+ letters. Main outcome measures: new onset of SD-OCT-determined GA and VA loss. Results: We identified multiple retinal and subretinal SD-OCT and demographic features from the baseline visit, each of which independently conveyed low to high risk of new-onset GA or VA loss on each of the follow-up visits at 1 or 2 years. Conclusion: We propose a risk-stratified classification of iAMD based on the combination of OCT-derived retinal features, age, gender and systemic variables for progression to OCT-determined GA and/or VA loss. After external validation, the composite early endpoints may be used as exclusion or inclusion criteria for future clinical studies of iAMD focused on prevention of GA progression or VA loss.
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A conceptual model is presented of two MW-scale low enthalpy mine water geothermal heat pump schemes that are being developed in Tyneside, UK. The Abbotsford Road scheme (54.955° N 1.556° W) is operating (as of May 2021) at 20-30 L/s, abstracting groundwater (and heat) from an unmined Coal Measures Upper Aquifer System (UAS) and reinjecting to the deeper High Main Aquifer System (HMAS), associated with the High Main (E) coal workings and the overlying High Main Post sandstone. A similar scheme, 700 m away at Nest Road (54.959° N 1.564° W), abstracts at 40 L/s from the HMAS, recovers heat from the mine water and reinjects the thermally spent water to deeper workings associated with the Hutton (L), Harvey-Beaumont (N) (and possibly other) coal seams, termed the Deep Mined Aquifer System (DMAS). The three aquifer systems are vertically discontinuous and possess different hydraulic (storage, transmissivity and continuity) properties that would have been near-impossible to predict in advance of drilling. At the sites, 10 boreholes were drilled to obtain five usable production/reinjection boreholes. Development of mine water geothermal energy schemes thus carries a significant project risk, and also a potential ongoing maintenance burden related to iron hydroxide scaling. These do not preclude mine water geothermal as a useful low carbon heating and cooling technology, but the involvement of skilled hydrogeologists, hydrochemists, mining and groundwater engineers is a pre-requisite.
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Energía Geotérmica , Agua Subterránea , Minería , Reino Unido , AguaRESUMEN
BH3 mimetics are increasingly used as anti-cancer therapeutics either alone or in conjunction with other chemotherapies. However, mounting evidence has also demonstrated that BH3 mimetics modulate varied amounts of apoptotic signaling in healthy immune populations. In order to maximize their clinical potential, it will be essential to understand how BH3 mimetics affect discrete immune populations and to determine how BH3 mimetic pressure causes immune system adaptation. Here we focus on the BCL-2 specific inhibitor venetoclax (ABT-199) and its effects following short-term and long-term BCL-2 blockade on T cell subsets. Seven day "short-term" ex vivo and in vivo BCL-2 inhibition led to divergent cell death sensitivity patterns in CD8+ T cells, CD4+ T cells, and Tregs resulting in shifting of global T cell populations towards a more memory T cell state with increased expression of BCL-2, BCL-XL, and MCL-1. However, twenty-eight day "long-term" BCL-2 blockade following T cell-depleted bone marrow transplantation did not lead to changes in the global T cell landscape. Despite the lack of changes in T cell proportions, animals treated with venetoclax developed CD8+ and CD4+ T cells with high levels of BCL-2 and were more resistant to apoptotic stimuli following expansion post-transplant. Further, we demonstrate through RNA profiling that T cells adapt while under BCL-2 blockade post-transplant and develop a more activated genotype. Taken together, these data emphasize the importance of evaluating how BH3 mimetics affect the immune system in different treatment modalities and disease contexts and suggest that venetoclax should be further explored as an immunomodulatory compound.
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Antineoplásicos/uso terapéutico , Compuestos Bicíclicos Heterocíclicos con Puentes/uso terapéutico , Muerte Celular/efectos de los fármacos , Células T de Memoria/efectos de los fármacos , Sulfonamidas/uso terapéutico , Animales , Antineoplásicos/farmacología , Apoptosis , Compuestos Bicíclicos Heterocíclicos con Puentes/farmacología , Línea Celular Tumoral , Humanos , Ratones , Sulfonamidas/farmacologíaRESUMEN
There is a significant body of research that has identified specific, high-end cognitive demand activities and lifestyles that may play a role in building cognitive brain reserve, including volume changes in gray matter and white matter, increased structural connectivity, and enhanced categorical perception. While normal aging produces trends of decreasing white matter (WM) integrity, research on cognitive brain reserve suggests that complex sensory-motor activities across the life span may slow down or reverse these trends. Previous research has focused on structural and functional changes to the human brain caused by training and experience in both linguistic (especially bilingualism) and musical domains. The current research uses diffusion tensor imaging to examine the integrity of subcortical white matter fiber tracts in lifelong musicians. Our analysis, using Tortoise and ICBM-81, reveals higher fractional anisotropy, an indicator of greater WM integrity, in aging musicians in bilateral superior longitudinal fasciculi and bilateral uncinate fasciculi. Statistical methods used include Fisher's method and linear regression analysis. Another unique aspect of this study is the accompanying behavioral performance data for each participant. This is one of the first studies to look specifically at musicianship across the life span and its impact on bilateral WM integrity in aging.
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Boron has become the principle proxy for the release of seawater-derived fluids into arc volcanics, linked to cross-arc variations in boron content and isotopic ratio. Because all ocean floor serpentinites so far analysed are strongly enriched in boron, it is generally assumed that if the uppermost slab mantle is hydrated, it will also be enriched in boron. Here we present the first measurements of boron and boron isotopes in fast-spread oceanic gabbros in the Pacific, showing strong take-up of seawater-derived boron during alteration. We show that in one-pass hydration of the upper mantle, as proposed for bend fault serpentinisation, boron will not reach the hydrated slab mantle. Only prolonged hydrothermal circulation, for example in a long-lived transform fault, can add significant boron to the slab mantle. We conclude that hydrated mantle in subducting slabs will only rarely contribute to boron enrichment in arc volcanics, or to deep mantle recycling.
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We have sequenced metagenome of the microbial community of a deep subsurface thermal aquifer in the Tomsk Region of the Western Siberia, Russia. Our goal was the recovery of near-complete genomes of the community members to enable accurate reconstruction of metabolism and ecological roles of the microbial majority, including previously unstudied lineages. The water, obtained via a 2.6 km deep borehole 1-R, was anoxic, with a slightly alkaline pH, and a temperature around 45°C. Microbial community, as revealed by 16S rRNA gene profiling over 2 years, mostly consisted of sulfate-reducing Firmicutes and Deltaproteobacteria, and uncultured lineages of the phyla Chlorofexi, Ignavibacteriae and Aminicenantes (OP8). 25 composite genomes with more than 90% completeness were recovered from metagenome and used for metabolic reconstruction. Members of uncultured lineages of Chlorofexi and Ignavibacteriae are likely involved in degradation of carbohydrates by fermentation, and are also capable of aerobic and anaerobic respiration. The Chlorofexi bacterium has the Wood-Ljungdahl pathway of CO2 fixation. The recently identified candidate phylum Riflebacteria accounted for 5%-10% of microbial community. Metabolic reconstruction of a member of Riflebacteria predicted that it is an anaerobe capable to grow on carbohydrates by fermentation or dissimilatory Fe(III) reduction.
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Bacterias/metabolismo , Metabolismo de los Hidratos de Carbono/genética , Agua Subterránea/microbiología , Microbiota/genética , Bacterias/clasificación , Bacterias/genética , Bacterias/aislamiento & purificación , Fermentación , Genoma Bacteriano/genética , Agua Subterránea/química , Metagenómica , Filogenia , ARN Ribosómico 16S/genética , Sulfatos/metabolismoRESUMEN
The role of fungi in metal cycling in acidic environments has been little explored to date. In this study, two acid-tolerant and metal-resistant Penicillium isolates, strains ShG4B and ShG4C, were isolated from a mine site in the Transbaikal area of Siberia (Russia). Waters at the mine site were characterized by extremely high metal concentrations: up to 18 g l-1 Fe and > 2 g l-1 each of Cu, Zn, Al, and As. Both isolates were identified as Penicillium spp. by phylogenetic analyses and they grew well in Czapek medium acidified to pH 2.5. Resistance to Cu, Cd, Ni, Co, and arsenate was in the range of 1-10 g l-1. Further experiments with Penicillium strain ShG4C demonstrated that growth in Cu-containing media was accompanied by the precipitation of Cu-oxalate (moolooite) and the formation of extracellular vesicles enriched in Cu on the mycelia. Vesicles were greatly reduced in size in Cd-containing media and were not formed in the presence of Ni or Co. Cd-oxalate was detected as a crystalline solid phase in Cd-exposed mycelia. Hydrated Ni-sulfate (retgersite) and Co-sulfate (bieberite) were detected in mycelia grown in the presence of Ni and Co, respectively. The results demonstrated that acid-tolerant and metal-resistant Penicillium constitute a component in extremophilic microbiomes, contributing to organic matter breakdown and formation of secondary solid phases at pH ranges found in acid rock drainage.
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Arsénico/metabolismo , Metales Pesados/metabolismo , Penicillium/metabolismo , Contaminantes Químicos del Agua/metabolismo , Proteínas Fúngicas/análisis , Penicillium/clasificación , Penicillium/genética , Filogenia , SiberiaRESUMEN
The blood-brain barrier is a microvascular network that (1) provides neuroprotection from metabolic and environmental toxins and (2) limits the delivery of therapeutics to the central nervous system (CNS). The ATP-binding cassette transporter P-glycoprotein contributes to the latter by actively pumping clinical substrates back into circulation before they can reach the brain parenchyma. Targeting P-glycoprotein has proven effective in increasing the delivery of therapeutics to their cerebral targets. We provide a novel mechanism to achieve this end in functioning, intact rat brain capillaries, whereby the bioactive phospholipid lysophosphatidic acid (LPA) and tricyclic antidepressant (TCA) amitriptyline reduce basal P-glycoprotein transport activity through a distinct lysophosphatidic acid 1 receptor-mediated signaling cascade that requires G-protein coupling, Src kinase, and ERK 1/2. Furthermore, we demonstrate the ability of LPA and TCA amitriptyline to decrease induced P-glycoprotein transport activity in a human SOD1 transgenic rat model of amyotrophic lateral sclerosis. This work may translate to new clinical strategies for increasing the cerebral penetration of therapeutics in patients suffering from CNS diseases marked by exacerbated pharmacoresistance.
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Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/metabolismo , Amitriptilina/farmacología , Permeabilidad Capilar/efectos de los fármacos , Lisofosfolípidos/farmacología , Receptores del Ácido Lisofosfatídico/metabolismo , Esclerosis Amiotrófica Lateral , Animales , Antidepresivos Tricíclicos/farmacología , Barrera Hematoencefálica/efectos de los fármacos , Barrera Hematoencefálica/metabolismo , Permeabilidad Capilar/fisiología , Humanos , Masculino , Microvasos/efectos de los fármacos , Microvasos/metabolismo , Ratas , Ratas Sprague-Dawley , Ratas Transgénicas , Transducción de Señal/efectos de los fármacos , Transducción de Señal/fisiologíaRESUMEN
Generic hydrochemical modelling of a grantoid-groundwater system, using the Russian software "HydroGeo", has been carried out with an emphasis on simulating the accumulation of uranium in the aqueous phase. The baseline model run simulates shallow granitoid aquifers (U content 5 ppm) under conditions broadly representative of southern Norway and southwestern Siberia: i.e. temperature 10 °C, equilibrated with a soil gas partial CO2 pressure (PCO2, open system) of 10-2.5 atm. and a mildly oxidising redox environment (Eh = +50 mV). Modelling indicates that aqueous uranium accumulates in parallel with total dissolved solids (or groundwater mineralisation M - regarded as an indicator of degree of hydrochemical evolution), accumulating most rapidly when M = 550-1000 mg L-1. Accumulation slows at the onset of saturation and precipitation of secondary uranium minerals at M = c. 1000 mg L-1 (which, under baseline modelling conditions, also corresponds approximately to calcite saturation and transition to Na-HCO3 hydrofacies). The secondary minerals are typically "black" uranium oxides of mixed oxidation state (e.g. U3O7 and U4O9). For rock U content of 5-50 ppm, it is possible to generate a wide variety of aqueous uranium concentrations, up to a maximum of just over 1 mg L-1, but with typical concentrations of up to 10 µg L-1 for modest degrees of hydrochemical maturity (as indicated by M). These observations correspond extremely well with real groundwater analyses from the Altai-Sayan region of Russia and Norwegian crystalline bedrock aquifers. The timing (with respect to M) and degree of aqueous uranium accumulation are also sensitive to Eh (greater mobilisation at higher Eh), uranium content of rocks (aqueous concentration increases as rock content increases) and PCO2 (low PCO2 favours higher pH, rapid accumulation of aqueous U and earlier saturation with respect to uranium minerals).
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Agua Subterránea/química , Modelos Químicos , Uranio/análisis , Contaminantes Radiactivos del Agua/análisis , Precipitación Química , Oxidación-ReducciónRESUMEN
Almost all the known isolates of acidophilic or acid-tolerant sulphate-reducing bacteria (SRB) belong to the spore-forming genus Desulfosporosinus in the Firmicutes. The objective of this study was to isolate acidophilic/acid-tolerant members of the genus Desulfovibrio belonging to deltaproteobacterial SRB. The sample material originated from microbial mat biomass submerged in mine water and was enriched for sulphate reducers by cultivation in anaerobic medium with lactate as an electron donor. A stirred tank bioreactor with the same medium composition was inoculated with the sulphidogenic enrichment. The bioreactor was operated with a temporal pH gradient, changing daily, from an initial pH of 7.3 to a final pH of 3.7. Among the bacteria in the bioreactor culture, Desulfovibrio was the only SRB group retrieved from the bioreactor consortium as observed by 16S rRNA-targeted denaturing gradient gel electrophoresis. Moderately acidophilic/acid-tolerant isolates belonged to Desulfovibrio aerotolerans-Desulfovibrio carbinophilus-Desulfovibrio magneticus and Desulfovibrio idahonensis-Desulfovibrio mexicanus clades within the genus Desulfovibrio. A moderately acidophilic strain, Desulfovibrio sp. VK (pH optimum 5.7) and acid-tolerant Desulfovibrio sp. ED (pH optimum 6.6) dominated in the bioreactor consortium at different time points and were isolated in pure culture.
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Adaptación Biológica , Reactores Biológicos , Desulfovibrio/aislamiento & purificación , Desulfovibrio/metabolismo , Microbiología Ambiental , Concentración de Iones de Hidrógeno , ARN Ribosómico 16S/genética , Desulfovibrio/clasificación , Desulfovibrio/genética , Minería , Filogenia , Análisis de Secuencia de ADN , Microbiología del AguaRESUMEN
P-glycoprotein (P-gp), Breast cancer resistance protein (BCRP) and Multidrug resistance-associated protein 2 (MRP2) residing at the blood-brain barrier (BBB) and the blood-spinal cord barrier (BSCB) are major obstacles for drug delivery to the Central Nervous System (CNS). Disease-induced changes of these xenobiotic transporters at the CNS barriers have been previously documented. Changes in the functional expression of these transporters at the CNS barriers would limit the clinical efficacy of therapeutic agents targeting the CNS. In this study, we characterized the changes in expression and efflux activity of P-gp, BCRP and MRP2 at the BBB and BSCB of an amyotrophic lateral sclerosis (ALS) SOD1-G93A transgenic rat model across the three stages of disease progression: pre-onset, onset and symptomatic. Up-regulation of P-gp and BCRP at the BBB and BSCB during disease progression of ALS would reduce drug entry to the CNS, while any decreases in transport activity would increase drug entry. In SOD rats at the ALS symptomatic stage, we observed increases in both P-gp transport activity and expression compared to age-matched wildtypes. BCRP and MRP2 levels were unchanged in these animals. Immunohistochemical analysis in brain and spinal cord capillaries of SOD rats from all three ALS stages and age-matched wildtypes showed no differences in nuclear localization of a known P-gp regulator, nuclear factor kappa-light-chain-enhancer of activated B cells (NFκB). It suggests that NFκB may have a limited role during P-gp induction observed in our study and additional signaling pathways could be responsible for this response. Our observations imply that novel pharmacological approaches for treating ALS require selecting drugs that are not P-gp substrates in order to improve therapeutic efficacy in the CNS during ALS progression.
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Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/metabolismo , Esclerosis Amiotrófica Lateral/metabolismo , Barrera Hematoencefálica/metabolismo , Sistema Nervioso Central/metabolismo , Esclerosis Amiotrófica Lateral/tratamiento farmacológico , Animales , Transporte Biológico/fisiología , Modelos Animales de Enfermedad , Proteínas de Transporte de Membrana/metabolismo , Ratas , Regulación hacia ArribaRESUMEN
Microbial sulfate reduction in acid mine drainage is still considered to be confined to anoxic conditions, although several reports have shown that sulfate-reducing bacteria occur under microaerophilic or aerobic conditions. We have measured sulfate reduction rates of up to 60 nmol S cm(-3) day(-1) in oxidized layers of gold mine tailings in Kuzbass (SW Siberia). A novel, acidophilic, copper-tolerant Desulfosporosinus sp. I2 was isolated from the same sample and its genome was sequenced. The genomic analysis and physiological data indicate the involvement of transporters and additional mechanisms to tolerate metals, such as sequestration by polyphosphates. Desulfosporinus sp. I2 encodes systems for a metabolically versatile life style. The genome possessed a complete Embden-Meyerhof pathway for glycolysis and gluconeogenesis. Complete oxidation of organic substrates could be enabled by the complete TCA cycle. Genomic analysis found all major components of the electron transfer chain necessary for energy generation via oxidative phosphorylation. Autotrophic CO2 fixation could be performed through the Wood-Ljungdahl pathway. Multiple oxygen detoxification systems were identified in the genome. Taking into account the metabolic activity and genomic analysis, the traits of the novel isolate broaden our understanding of active sulfate reduction and associated metabolism beyond strictly anaerobic niches.
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Minería , Peptococcaceae/genética , Adaptación Fisiológica , Cobre/metabolismo , Genómica , Oro , Oxidación-Reducción , Peptococcaceae/fisiología , Filogenia , Siberia , Sulfatos/metabolismoRESUMEN
This research project aimed to examine the perceived value sign-off mentors (SOMs) in midwifery have for their role. Using a phenomenological approach, the results were drawn from in-depth interviews. The project included a literature review, methodology, results and discussion. The results indicate that mentors enjoy their role and they see themselves as essentials to the delivery of pre-registration midwifery programmes and for the supervision and assessment of student midwives. Mentors are not sure if student midwives value their sign-off mentor, or whether senior management is aware of the sign-off role and its value. This project also confirms previous findings from other studies, particularly the problem of finding time to complete student assessment paper work, support students in clinical practice and whether there are enough SOMs within clinical practice. The study does not conclude that the issues raised are distinctive to midwifery, potentially all of the points raised translate to the various forms of nursing practice.