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1.
J Environ Manage ; 356: 120526, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38492423

RESUMEN

The equilibrium of the marine ecosystem is currently threatened by several constraints, among which climate change and anthropogenic activities stand out. Indeed, these factors favour the growth of macroalgae, which sometimes end up stranded on the beaches at the end of their life cycle, forming what is known as beach wrack. Despite its undeniable important ecological role on beaches, as it is an important source of organic matter (OM), and provides food and habitat for several invertebrates, reptiles, small mammals, and shorebirds, the overaccumulation of beach wrack is often associated with the release of greenhouse gases, negatively impacting tourist activities, and generating economic expenses for its removal. Although currently beach wrack is mainly treated as a waste, it can be used for numerous potential applications in distinct areas. This review aimed at providing a solid point of view regarding the process of wrack formation, its spatiotemporal location, as well as its importance and risks. It also contains the current advances of the research regarding sustainable alternatives to valorise this organic biomass, that range from bioenergy production to the incorporation of wrack in agricultural soils, considering a circular economy concept. Although there are some concerns regarding wrack utilisation, from its variable availability to a possible soil contamination with salts and other contaminants, this review comprises the overall beneficial effects of the incorporation of this residue particularly in the organic agricultural model, strengthening the conversion of this wasted biomass into a valuable resource.


Asunto(s)
Ecosistema , Algas Marinas , Animales , Agricultura , Biomasa , Suelo/química , Mamíferos
2.
Neurol Sci ; 44(2): 703-708, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36335281

RESUMEN

OBJECTIVE: Wernicke encephalopathy (WE) is a neuropsychiatric syndrome caused by thiamine deficiency. Despite its low sensitivity, brain magnetic resonance imaging (MRI) is the most useful diagnostic technique. Our aim was to investigate whether the timing of the imaging study, and thiamine replacement can influence brain MRI findings in these patients. METHODS: Retrospective observational study of hospitalized patients between January/2008 and December/2020 with a clinical diagnosis of WE. Data from clinical presentation, diagnostic features, therapeutic approach, and outcomes were collected. RESULTS: We identified 41 patients (55 ± 13.3 years) with WE. Brain MRI was performed in 36 patients, and one third had T2/FLAIR hyperintensities suggestive of WE. We found an association between a history of poor diet and periventricular hyperintensities (p = 0.023), especially on the ventral surface of the thalamus and the periaqueductal region. It was found that the odds of having a typical imaging of WE decreased by 5.3% for each additional unit (100 mg) of thiamine administered (p = 0.046) (95% CI [0.89, 0.99]). On the other hand, the number of days from clinical presentation was not found to be a viable predictor (p = 0.254) (95% CI [0.88, 1.03]) Recovery was positively correlated with the total dose of thiamine received until discharge (p = 0.020). CONCLUSIONS: MRI hyperintensities seem to be dependent on the timing of thiamine correction and, particularly, on the thiamine dosage prescribed at admission. Nevertheless, thiamine replacement should not be delayed, as its timely prescription is associated with a better prognosis at discharge.


Asunto(s)
Síndrome de Korsakoff , Deficiencia de Tiamina , Encefalopatía de Wernicke , Humanos , Encefalopatía de Wernicke/diagnóstico por imagen , Centros de Atención Terciaria , Deficiencia de Tiamina/complicaciones , Deficiencia de Tiamina/diagnóstico por imagen , Tiamina/uso terapéutico , Imagen por Resonancia Magnética
3.
Sensors (Basel) ; 23(17)2023 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-37688089

RESUMEN

Enhancing recovery is a fundamental component of high-performance sports training since it enables practitioners to potentiate physical performance and minimise the risk of injuries. Using a new sports legging embedded with an intelligent system for electrostimulation, localised heating and compression (completely embodied into the textile structures), we aimed to analyse acute recovery following a fatigue protocol. Surface electromyography- and torque-related variables were recorded on eight recreational athletes. A fatigue protocol conducted in an isokinetic dynamometer allowed us to examine isometric torque and consequent post-exercise acute recovery after using the sports legging. Regarding peak torque, no differences were found between post-fatigue and post-recovery assessments in any variable; however, pre-fatigue registered a 16% greater peak torque when compared with post-fatigue for localised heating and compression recovery methods. Our data are supported by recent meta-analyses indicating that individual recovery methods, such as localised heating, electrostimulation and compression, are not effective to recover from a fatiguing exercise. In fact, none of the recovery methods available through the sports legging tested was effective in acutely recovering the torque values produced isometrically.


Asunto(s)
Atletas , Rendimiento Atlético , Humanos , Ejercicio Físico , Terapia por Ejercicio , Fatiga
4.
J Perinat Med ; 50(2): 185-191, 2022 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-34727592

RESUMEN

OBJECTIVES: Maternal and fetal complications can occur in pregnant kidney transplant recipients. Since these are high-risk pregnancies, they require a multidisciplinary follow-up to prematurely detect adverse events. Identifying factors that would affect fetal, maternal and graft outcomes is essential to further stratify the risk of pregnant kidney transplant recipients. METHODS: All pregnancies in kidney transplant recipients followed in a single center for 30 years were included. Data included previous transplant information and blood and urine tests performed before pregnancy. Impact of graft function on fetal, maternal and graft outcomes was evaluated. RESULTS: There were 41 pregnancies among 34 patients. Mean gestational age of 35 ± 3 weeks. Caesarean section was performed in 69.4% of patients. Five pregnancies were unsuccessful (12.2%). Four patients suffered an acute graft dysfunction (9.8%) and 12 (29.3%) had a serious maternal hypertensive disorder (preeclampsia, eclampsia or HELLP syndrome). Graft function before pregnancy showed significant correlation with adverse outcomes. CONCLUSIONS: A proteinuria >669 mg/g, serum creatinine >1.75 mg/dL and glomerular filtration rate <36.2 mL/min/1.73 m2 before pregnancy were correlated to graft dysfunction during pregnancy. Similar values of proteinuria were also associated with a risk of maternal hypertensive disorders and pregnancy failure. Therefore, in patients with proteinuria and graft dysfunction, follow-up should be stricter to quickly detect complications.


Asunto(s)
Trasplante de Riñón , Preeclampsia , Complicaciones del Embarazo , Cesárea/efectos adversos , Creatinina , Femenino , Humanos , Lactante , Riñón , Trasplante de Riñón/efectos adversos , Embarazo , Complicaciones del Embarazo/diagnóstico , Complicaciones del Embarazo/epidemiología , Complicaciones del Embarazo/etiología , Resultado del Embarazo/epidemiología
5.
Ergonomics ; 65(9): 1194-1201, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34930095

RESUMEN

The aim of this study was to investigate if increased load carriage, in male military personnel, can affect the lower limbs kinematics. Twelve male military volunteers from the Portuguese Army were recruited and evaluated in an unloaded and loaded gait condition. Linear kinematics and lower limbs joint angle at heel strike, midstance and toe off were calculated. The stance, swing and double support times were found to be different between load conditions (p < 0.05). There was an interaction between load and limb (p < 0.05) for joint angles, during midstance, with limbs performing different movements in the frontal plane during loaded gait. Load increase had a different effect on the right knee, with a reduction in the abduction (valgus). This study may be beneficial in offering suggestion to improve the performance of gait with load and in an attempt to help prevent possible injuries. Practitioner summary: Increased load can affect lower limbs of male soldiers at the pelvic, hip and knee angles on the frontal plane, which can alter the joint force distribution. While these alterations may indicate protective mechanics, load management procedures should be implemented along with gait monitoring to avoid negative effects in performance.


Asunto(s)
Personal Militar , Fenómenos Biomecánicos , Marcha , Humanos , Articulación de la Rodilla , Extremidad Inferior , Masculino , Soporte de Peso
6.
7.
Nature ; 517(7532): 77-80, 2015 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-25317564

RESUMEN

The mechanisms that underlie the origin of major prokaryotic groups are poorly understood. In principle, the origin of both species and higher taxa among prokaryotes should entail similar mechanisms--ecological interactions with the environment paired with natural genetic variation involving lineage-specific gene innovations and lineage-specific gene acquisitions. To investigate the origin of higher taxa in archaea, we have determined gene distributions and gene phylogenies for the 267,568 protein-coding genes of 134 sequenced archaeal genomes in the context of their homologues from 1,847 reference bacterial genomes. Archaeal-specific gene families define 13 traditionally recognized archaeal higher taxa in our sample. Here we report that the origins of these 13 groups unexpectedly correspond to 2,264 group-specific gene acquisitions from bacteria. Interdomain gene transfer is highly asymmetric, transfers from bacteria to archaea are more than fivefold more frequent than vice versa. Gene transfers identified at major evolutionary transitions among prokaryotes specifically implicate gene acquisitions for metabolic functions from bacteria as key innovations in the origin of higher archaeal taxa.


Asunto(s)
Archaea/clasificación , Archaea/genética , Bacterias/genética , Evolución Molecular , Transferencia de Gen Horizontal/genética , Genes Arqueales/genética , Genes Bacterianos/genética , Archaea/metabolismo , Proteínas Arqueales/genética , Bacterias/metabolismo , Genoma Arqueal/genética , Filogenia
8.
Nature ; 524(7566): 427-32, 2015 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-26287458

RESUMEN

Chloroplasts arose from cyanobacteria, mitochondria arose from proteobacteria. Both organelles have conserved their prokaryotic biochemistry, but their genomes are reduced, and most organelle proteins are encoded in the nucleus. Endosymbiotic theory posits that bacterial genes in eukaryotic genomes entered the eukaryotic lineage via organelle ancestors. It predicts episodic influx of prokaryotic genes into the eukaryotic lineage, with acquisition corresponding to endosymbiotic events. Eukaryotic genome sequences, however, increasingly implicate lateral gene transfer, both from prokaryotes to eukaryotes and among eukaryotes, as a source of gene content variation in eukaryotic genomes, which predicts continuous, lineage-specific acquisition of prokaryotic genes in divergent eukaryotic groups. Here we discriminate between these two alternatives by clustering and phylogenetic analysis of eukaryotic gene families having prokaryotic homologues. Our results indicate (1) that gene transfer from bacteria to eukaryotes is episodic, as revealed by gene distributions, and coincides with major evolutionary transitions at the origin of chloroplasts and mitochondria; (2) that gene inheritance in eukaryotes is vertical, as revealed by extensive topological comparison, sparse gene distributions stemming from differential loss; and (3) that continuous, lineage-specific lateral gene transfer, although it sometimes occurs, does not contribute to long-term gene content evolution in eukaryotic genomes.


Asunto(s)
Eucariontes/genética , Evolución Molecular , Modelos Genéticos , Orgánulos/genética , Simbiosis/genética , Archaea/genética , Bacterias/genética , Análisis por Conglomerados , Eucariontes/clasificación , Células Eucariotas/metabolismo , Transferencia de Gen Horizontal/genética , Genoma/genética , Mitocondrias/genética , Filogenia , Plastidios/genética , Células Procariotas/metabolismo , Proteoma/genética , Factores de Tiempo
9.
Sensors (Basel) ; 21(2)2021 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-33430452

RESUMEN

Human postural control is a fundamental ability for static and dynamic tasks, especially in hiper- and hipo-functional populations, such as the elderly. The Equimetrix is a clinical device developed to assess both the base of support (BoS) and the center of mass (CoM) dynamics, thus allowing their use as new evaluation and training tools. This study aims to perform a criteria based validation of Equimetrix by comparing the BoS and CoM data with gold-standard equipment. A motion capture system, force platform, and pressure mat were used to calculate the CoM, center of pressure (CoP) and BoS during bipedal, unipedal, feet together and full tandem stances. Results demonstrate an excellent reliability of Equimetrix in terms of spatial accuracy of the CoM, although over-estimating the CoM height. Differences were found when comparing Mean velocity Path with the CoM, but not with the CoP, indicating a lower reliability in time-based parameters. The Equimetrix presents a tendency to overestimate the BoS, with mixed reliability values, which may be related to the different size of sensing elements between the Equimetrix and the pressure sensing mat. These are encouraging results that should be further explored during dynamic tasks.


Asunto(s)
Pie , Equilibrio Postural , Anciano , Fenómenos Biomecánicos , Humanos , Movimiento (Física) , Reproducibilidad de los Resultados
10.
Sensors (Basel) ; 21(23)2021 Dec 03.
Artículo en Inglés | MEDLINE | ID: mdl-34884093

RESUMEN

The purpose of this study was to investigate if the use of an ankle foot orthosis in passive mode (without actuation) could modify minimum foot clearance, and if there are any compensatory mechanisms to enable these changes during treadmill gait at a constant speed. Eight participants walked on an instrumented treadmill without and with an ankle foot orthosis on the dominant limb at speeds of 0.8, 1.2, and 1.6 km/h. For each gait cycle, the minimum foot clearance and some gait linear kinematic parameters were calculated by an inertial motion capture system. Additionally, maximum hip and knee flexion and maximum ankle plantar flexion were calculated. There were no significant differences in the minimum foot clearance between gait conditions and lower limbs. However, differences were found in the swing, stance and step times between gait conditions, as well as between limbs during gait with orthosis (p < 0.05). An increase in hip flexion during gait with orthosis was observed for all speeds, and different ankle ranges of motion were observed according to speed (p < 0.05). Thus, the use of an ankle foot orthosis in passive mode does not significantly hinder minimum foot clearance, but can change gait linear and angular parameters in non-pathological individuals.


Asunto(s)
Tobillo , Ortesis del Pié , Articulación del Tobillo , Fenómenos Biomecánicos , Pie , Marcha , Humanos , Rango del Movimiento Articular , Caminata
11.
J Aging Phys Act ; 29(3): 382-390, 2021 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-33049699

RESUMEN

Regular sport practice could prevent age-related changes in tendinous tissues. The purpose of the study was to investigate the effect of regular badminton practice on patellar and Achilles tendon mechanical properties in senior competitive badminton players (>35 years old) and to compare the results with physically active people matched by age. One hundred ninety-two badminton players and 193 physically active people were divided by age into four groups, between 35 and 44 (U45), between 45 and 54 (U55), between 55 and 64 (U65), and over 65 (O65) years old. A LogiqS8 transducer in elastography mode and a MyotonPRO myotonometer were used to assess patellar and Achilles mechanical properties. Achilles tendon stiffness was higher in the control group than the badminton players for the U45, U55, and O65 age groups (p < .01). Also, the elastography index was higher in the control group than the badminton players for the U45, U55, U65, and O65 age groups (p < .05). In conclusion, regular badminton practice could prevent the decline in mechanical properties of the patellar and Achilles tendons.


Asunto(s)
Tendón Calcáneo , Deportes de Raqueta , Tendón Calcáneo/diagnóstico por imagen , Humanos
12.
Medicina (Kaunas) ; 57(4)2021 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-33923478

RESUMEN

Background and Objectives: Ovarian surgical ablation (OSA) in estrogen receptor-positive (ER+) breast cancer is usually performed to halt ovarian function in premenopausal patients. Since alternative pharmacological therapy exists and few studies have investigated why surgery is still performed, we aimed to analyze the reasons for the use of OSA despite the remaining controversy. Materials and Methods: Premenopausal ER+ breast cancer patients treated at a tertiary center (2005-2011) were selected, and patients with germline mutations were excluded. Results: Seventy-nine patients met the inclusion criteria. Globally, the main reasons for OSA included: continued menstruation despite hormone therapy with or without ovarian medical ablation (OMA) (34.2%), patient informed choice (31.6%), disease progression (16.5%), gynecological disease requiring surgery (13.9%), and tamoxifen intolerance/contraindication (3.8%). In women aged ≥45 years, patient choice was significantly more frequently the reason for OSA (47.4% versus 17.1% (p = 0.004)). For those aged <45 years, salvation attempts were significantly more frequent as compared to older women (26.8% versus 5.3% (p = 0.01)). In 77.8% of women undergoing OSA with menstrual cycle maintenance, surgery was performed 1-5 years after diagnosis, while surgery was performed earlier (0-3 months after diagnosis) in patients undergoing OSA as an informed choice (56.0%), as a salvation attempt (53.8%), or due to gynecological disease (63.6%). The leading reason for OSA in women previously undergoing OMA was continued menstruation (60.0%). Conclusions: This study suggests a possible failure of pharmacological ovarian suppression and reinforces the need for shared decision-making with patients when discussing treatment strategies, although validation by further studies is warranted due to our limited sample size.


Asunto(s)
Neoplasias de la Mama , Anciano , Neoplasias de la Mama/cirugía , Femenino , Humanos , Persona de Mediana Edad , Premenopausia , Tamoxifeno
13.
Graefes Arch Clin Exp Ophthalmol ; 258(8): 1771-1777, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32367284

RESUMEN

BACKGROUND: Migraine symptoms are frequently referred by glaucoma patients. Although most studies analyze headache in the acute setting of angle closure, many patients with chronic occludable angles also complain of headaches. The aim of this study was to determine the impact of laser peripheral iridotomy (LPI) on the magnitude and frequency of headache symptoms in patients with occludable angles. METHODS: Prospective cohort study. Patients with indication for prophylactic LPI due to occludable iridocorneal angle were included. Headache symptoms were assessed before and at least 4 weeks after LPI using the Headache Impact Test-6 (HIT-6) questionnaire. A HIT-6 score of ≥ 50 points was labeled as a clinically significant headache. RESULTS: Thirty-one subjects were included. Prophylactic LPI was performed in 60 eyes, as 2 patients were pseudophakic in the fellow eye. Baseline HIT-6 score was 59.9 ± 11.8, with over three quarters of these patients scoring higher than 50 points (n = 24). A statistically significant reduction in HIT-6 score was found after LPI treatment (45.4 ± 7.7, p < 0.01). Sub-analysis within the clinically symptomatic subjects disclosed a significant improvement after treatment in this group (baseline, 65.3 ± 6.2 vs post-LPI 46.2 ± 8.3, p < 0.01), with a high baseline HIT-6 score being predictive of a symptomatic improvement after LPI (χ2(8) = 15.3, p = 0.001). This is mimicked from the patient's perspective, as the two subjective questions after LPI, concerning pain intensity and frequency, report that 79.2% had a statistically significant improvement of the headaches. CONCLUSIONS: Within our sample, the majority of patients with occludable angles had clinically relevant headaches. LPI provided symptomatic relief in the majority of those patients with high HIT-6 scores. Further studies are needed to explore the relationships between headache and angle anatomy.


Asunto(s)
Glaucoma de Ángulo Cerrado/cirugía , Cefalea/etiología , Presión Intraocular/fisiología , Iridectomía/métodos , Terapia por Láser/métodos , Láseres de Estado Sólido/uso terapéutico , Tomografía de Coherencia Óptica/métodos , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Glaucoma de Ángulo Cerrado/complicaciones , Glaucoma de Ángulo Cerrado/fisiopatología , Gonioscopía , Cefalea/diagnóstico , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos
14.
BMC Bioinformatics ; 20(1): 187, 2019 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-30991966

RESUMEN

BACKGROUND: Biological pathways represent chains of molecular interactions in biological systems that jointly form complex dynamic networks. The network structure changes from the significance of biological experiments and layout algorithms often sacrifice low-level details to maintain high-level information, which complicates the entire image to large biochemical systems such as human metabolic pathways. RESULTS: Our work is inspired by concepts from urban planning since we create a visual hierarchy of biological pathways, which is analogous to city blocks and grid-like road networks in an urban area. We automatize the manual drawing process of biologists by first partitioning the map domain into multiple sub-blocks, and then building the corresponding pathways by routing edges schematically, to maintain the global and local context simultaneously. Our system incorporates constrained floor-planning and network-flow algorithms to optimize the layout of sub-blocks and to distribute the edge density along the map domain. We have developed the approach in close collaboration with domain experts and present their feedback on the pathway diagrams based on selected use cases. CONCLUSIONS: We present a new approach for computing biological pathway maps that untangles visual clutter by decomposing large networks into semantic sub-networks and bundling long edges to create space for presenting relationships systematically.


Asunto(s)
Biología Computacional/métodos , Redes y Vías Metabólicas , Modelos Biológicos , Algoritmos , Humanos , Mapas como Asunto
15.
Mol Microbiol ; 109(3): 385-400, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29989674

RESUMEN

Haem is an essential cofactor in central metabolic pathways in the vast majority of living systems. Prokaryotes acquire haem via haem biosynthesis pathways, and some also utilize haem uptake systems, yet it remains unclear how they balance haem requirements with the paradox that free haem is toxic. Here, using the model pathogen Staphylococcus aureus, we report that IsdG, one of two haem oxygenase enzymes in the haem uptake system, inhibits the formation of haem via the internal haem biosynthesis route. More specifically, we show that IsdG decreases the activity of ferrochelatase and that the two proteins interact both in vitro and in vivo. Further, a bioinformatics analysis reveals that a significant number of haem biosynthesis pathway containing organisms possess an IsdG-homologue and that those with both biosynthesis and uptake systems have at least two haem oxygenases. We conclude that IsdG-like proteins control intracellular haem levels by coupling the two pathways. IsdG is thus a target for the treatment of S. aureusinfections.


Asunto(s)
Hemo/biosíntesis , Oxigenasas/metabolismo , Infecciones Estafilocócicas/microbiología , Staphylococcus aureus/enzimología , Animales , Línea Celular , Ferroquelatasa/genética , Ferroquelatasa/metabolismo , Genes Bacterianos/genética , Humanos , Hierro/metabolismo , Macrófagos/microbiología , Ratones , Oxigenasas/genética , ARN Bacteriano/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Staphylococcus aureus/genética
16.
Plant Cell ; 27(7): 1827-33, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25818624

RESUMEN

A pivotal step in the transformation of an endosymbiotic cyanobacterium to a plastid some 1.5 billion years ago was the evolution of a protein import apparatus, the TOC/TIC machinery, in the common ancestor of Archaeplastida. Recently, a putative new TIC member was identified in Arabidopsis thaliana: TIC214. This finding is remarkable for a number of reasons: (1) TIC214 is encoded by ycf1, so it would be the first plastid-encoded protein of this apparatus; (2) ycf1 is unique to the green lineage (Chloroplastida) but entirely lacking in glaucophytes (Glaucophyta) and the red lineage (Rhodophyta) of the Archaeplastida; (3) ycf1 has been shown to be one of the few indispensable plastid genes (aside from the ribosomal machinery), yet it is missing in the grasses; and (4) 30 years of previous TOC/TIC research missed it. These observations prompted us to survey the evolution of ycf1. We found that ycf1 is not only lacking in grasses and some parasitic plants, but also for instance in cranberry (Ericaceae). The encoded YCF proteins are highly variable, both in sequence length and in the predicted number of N-terminal transmembrane domains. The evolution of the TOC/TIC machinery in the green lineage experienced specific modifications, but our analysis does not support YCF1 to be a general green TIC. It remains to be explained how the apparent complete loss of YCF1 can be tolerated by some embryophytes and whether what is observed for YCF1 function in a member of the Brassicaceae is also true for, e.g., algal and noncanonical YCF1 homologs.


Asunto(s)
Proteínas de Plantas/metabolismo , Plantas/metabolismo , Evolución Molecular , Variación Genética , Filogenia , Plastidios/genética
17.
Bioessays ; 38(9): 850-6, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27339178

RESUMEN

Metagenomics bears upon all aspects of microbiology, including our understanding of mitochondrial and eukaryote origin. Recently, ribosomal protein phylogenies show the eukaryote host lineage - the archaeal lineage that acquired the mitochondrion - to branch within the archaea. Metagenomic studies are now uncovering new archaeal lineages that branch more closely to the host than any cultivated archaea do. But how do they grow? Carbon and energy metabolism as pieced together from metagenome assemblies of these new archaeal lineages, such as the Deep Sea Archaeal Group (including Lokiarchaeota) and Bathyarchaeota, do not match the physiology of any cultivated microbes. Understanding how these new lineages live in their environment is important, and might hold clues about how mitochondria arose and how the eukaryotic lineage got started. Here we look at these exciting new metagenomic studies, what they say about archaeal physiology in modern environments, how they impact views on host-mitochondrion physiological interactions at eukaryote origin.


Asunto(s)
Archaea/genética , Metabolismo Energético , Eucariontes/genética , Metagenómica , Mitocondrias , Filogenia , Eucariontes/metabolismo
18.
Biochim Biophys Acta ; 1857(8): 1027-1038, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27150504

RESUMEN

Life arose in a world without oxygen and the first organisms were anaerobes. Here we investigate the gene repertoire of the prokaryote common ancestor, estimating which genes it contained and to which lineages of modern prokaryotes it was most similar in terms of gene content. Using a phylogenetic approach we found that among trees for all 8779 protein families shared between 134 archaea and 1847 bacterial genomes, only 1045 have sequences from at least two bacterial and two archaeal groups and retain the ancestral archaeal-bacterial split. Among those, the genes shared by anaerobes were identified as candidate genes for the prokaryote common ancestor, which lived in anaerobic environments. We find that these anaerobic prokaryote common ancestor genes are today most frequently distributed among methanogens and clostridia, strict anaerobes that live from low free energy changes near the thermodynamic limit of life. The anaerobic families encompass genes for bifunctional acetyl-CoA-synthase/CO-dehydrogenase, heterodisulfide reductase subunits C and A, ferredoxins, and several subunits of the Mrp-antiporter/hydrogenase family, in addition to numerous S-adenosyl methionine (SAM) dependent methyltransferases. The data indicate a major role for methyl groups in the metabolism of the prokaryote common ancestor. The data furthermore indicate that the prokaryote ancestor possessed a rotor stator ATP synthase, but lacked cytochromes and quinones as well as identifiable redox-dependent ion pumping complexes. The prokaryote ancestor did possess, however, an Mrp-type H(+)/Na(+) antiporter complex, capable of transducing geochemical pH gradients into biologically more stable Na(+)-gradients. The findings implicate a hydrothermal, autotrophic, and methyl-dependent origin of life. This article is part of a Special Issue entitled 'EBEC 2016: 19th European Bioenergetics Conference, Riva del Garda, Italy, July 2-6, 2016', edited by Prof. Paolo Bernardi.


Asunto(s)
Archaea/metabolismo , Proteínas Arqueales/metabolismo , Proteínas Bacterianas/metabolismo , Clostridiales/metabolismo , Methanobacteriaceae/metabolismo , Origen de la Vida , Anaerobiosis , Archaea/genética , Proteínas Arqueales/genética , Proteínas Bacterianas/genética , Evolución Biológica , Clostridiales/genética , Coenzima A Ligasas/genética , Coenzima A Ligasas/metabolismo , Ferredoxinas/genética , Ferredoxinas/metabolismo , Hidrogenasas/genética , Hidrogenasas/metabolismo , Redes y Vías Metabólicas , Methanobacteriaceae/genética , Metiltransferasas/genética , Metiltransferasas/metabolismo , Anotación de Secuencia Molecular , Filogenia , Biosíntesis de Proteínas , Ribosomas/química , Ribosomas/metabolismo
19.
Somatosens Mot Res ; 34(3): 185-188, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-29025294

RESUMEN

Most stroke lesions occur in the middle cerebral artery territory, presenting a high probability of damage of pathways with predominant ipsilesional disposition, mainly related to postural control. Despite the high probability of bilateral postural control dysfunction based on neuroanatomical fundaments, both research and clinical rehabilitation involving stroke subjects have been focused on contralesional side (also named affected side) impairments, while ipsilesional side (also named non-affected side) impairments have been attributed to an adaptive strategy. This paper aims to present a critical understanding about the state-of-the-art that sustains the hypothesis that stroke subjects with middle cerebral artery territory lesion at the subcortical level show an atypical behaviour in the ipsilateral side associated with the lesion itself and the possible implications.


Asunto(s)
Lateralidad Funcional/fisiología , Infarto de la Arteria Cerebral Media/fisiopatología , Infarto de la Arteria Cerebral Media/rehabilitación , Equilibrio Postural/fisiología , Humanos
20.
Muscle Nerve ; 54(3): 413-21, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-26851892

RESUMEN

INTRODUCTION: In this study we estimated the prevalence, incidence, and mortality of myasthenia gravis (MG) in northern Portugal and characterized the clinical features of the patients identified. METHODS: We used 2 data sources: clinical records from the hospitals and pyridostigmine prescription registers. RESULTS: On December 31, 2013, we estimated a point prevalence of 111.7 patients per million population. The highest prevalence was observed in the group >65 years of age, especially in men (288.1 per million). During 2013, we estimated an incidence rate of 6.3 per million per year. Among women, the incidence rate was highest in the 15-49-year age group; in men, incidence increased with age up to 22.1 per million in those >65 years old. The MG-related mortality rate was 0.5 per million. CONCLUSIONS: These figures are in keeping with similar studies and emphasize the importance of diagnosis and management of MG in elderly populations. Muscle Nerve 54: 413-421, 2016.


Asunto(s)
Miastenia Gravis/epidemiología , Adolescente , Adulto , Distribución por Edad , Anciano , Anticuerpos/sangre , Niño , Preescolar , Bases de Datos Factuales , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Miastenia Gravis/sangre , Examen Neurológico , Portugal/epidemiología , Prevalencia , Proteínas Tirosina Quinasas Receptoras/inmunología , Receptores Colinérgicos/inmunología , Estudios Retrospectivos , Adulto Joven
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