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1.
J Intern Med ; 290(3): 621-631, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33533521

RESUMO

BACKGROUND: The general medical impacts of coronavirus (COVID-19) are increasingly appreciated. However, its impact on neurocognitive, psychiatric health and quality of life (QoL) in survivors after the acute phase is poorly understood. We aimed to evaluate neurocognitive function, psychiatric symptoms and QoL in COVID-19 survivors shortly after hospital discharge. METHODS: This was a cross-sectional analysis of a prospective study of hospitalized COVID-19 survivors followed up for 2 months after discharge. A battery of standardized instruments evaluating neurocognitive function, psychiatric morbidity and QoL (mental and physical components) was administered by telephone. RESULTS: Of the 229 screened patients, 179 were included in the final analysis. Amongst survivors, the prevalence of moderately impaired immediate verbal memory and learning was 38%, delayed verbal memory (11.8%), verbal fluency (34.6%) and working memory (executive function) (6.1%), respectively. Moreover, 58.7% of patients had neurocognitive impairment in at least one function. Rates of positive screening for anxiety, depression and post-traumatic stress disorder were 29.6%, 26.8% and 25.1%, respectively. In addition, 39.1% of the patients had psychiatric morbidity. Low QoL for physical and mental components was detected in 44.1% and 39.1% of patients respectively. Delirium and psychiatric morbidity were associated with neurocognitive impairment, and female gender was related with psychiatric morbidity. CONCLUSION: Hospitalized COVID-19 survivors showed a considerable prevalence of neurocognitive impairment, psychiatric morbidity and poor QoL in the short term. It is uncertain if these impacts persist over the long term.


Assuntos
COVID-19/psicologia , Transtornos Cognitivos/etiologia , Transtornos da Memória/etiologia , Qualidade de Vida , Sobreviventes/psicologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Ansiedade/etiologia , Estudos Transversais , Depressão/etiologia , Feminino , Humanos , Masculino , Memória de Curto Prazo , Pessoa de Meia-Idade , Estudos Prospectivos , SARS-CoV-2 , Fatores Sexuais , Transtornos de Estresse Pós-Traumáticos/etiologia , Adulto Jovem
2.
Opt Lett ; 45(17): 4710-4713, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32870838

RESUMO

We address the resonant response and bistability of the exciton-polariton corner states in a higher-order nonlinear topological insulator realized with a kagome arrangement of microcavity pillars. Such states are resonantly excited and exist due to the balance between pump and losses, on one hand, and between nonlinearity and dispersion in inhomogeneous potential landscape, on the other hand, for pump energy around eigen-energies of corresponding linear localized modes. Localization of the nonlinear corner states in a higher-order topological insulator can be efficiently controlled by tuning pump energy. We link the mechanism of corner state formation with symmetry of the truncated kagome array. Corner states coexist with densely packed edge states but are well isolated from them in energy. Nonlinear corner states persist even in the presence of perturbations in a corner microcavity pillar.

3.
Ecotoxicol Environ Saf ; 162: 673-682, 2018 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-30025591

RESUMO

Petroleum can pollute pristine shorelines as a consequence of accidental spills or chronic leaks. In this study, the fate of petroleum hydrocarbons in soft pristine sediment of Caleta Valdés (Argentina) subject to ex situ simulated oil pollution was assessed. Sedimentary columns were exposed to medium and high concentrations of Escalante Crude Oil (ECO) and incubated in the laboratory during 30 days. Levels of aliphatic hydrocarbons at different depths of the sedimentary column were determined by gas chromatography. Oil penetration was limited to the first three centimetres in both treatments, and under this depth, hydrocarbons were clearly biogenic (terrestrial plants) as in the whole sedimentary column of the control assay. Bioturbation by macrobenthic infauna was strongly impacted by oil pollution which resulted in reduced sediment oxygenation and low burial of petroleum hydrocarbons. This may partly explain the limited hydrocarbon biodegradation observed, as indicated by the relatively high values of the ratios nC17/pristane, nC18/phytane, and total resolved aliphatic hydrocarbons/unresolved complex mixture. Correspondingly, at the end of the experiment the most probable number of hydrocarbon-degrading bacteria reached ~ 103 MPN g-1 dry weight. These values were lower than those found in chronically polluted coastal sediments, reflecting a low activity level of the oil-degrading community. The results highlight the low attenuation capacities of Caleta Valdés pristine sediments to recover its original characteristics in a short time period if an oil spill occurs. In this work, we present a novel and integrative tool to evaluate the fate of petroleum hydrocarbons and their potential damage on pristine sediments.


Assuntos
Bioensaio , Sedimentos Geológicos/química , Hidrocarbonetos/química , Petróleo/análise , Terpenos/química , Argentina , Bactérias/metabolismo , Biodegradação Ambiental , Cromatografia Gasosa , Poluição por Petróleo , Microbiologia do Solo , Poluentes do Solo/análise
4.
J Anim Breed Genet ; 133(2): 155-64, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26364918

RESUMO

This study presents the first insights into the genetic diversity and structure of the American donkey metapopulation. The primary objectives were to detect the main structural features underlying variability among American donkey populations, identify boundaries between differentiated gene pools, and draw the main colonization pathways since the introduction of donkeys into America in the 15th century. A panel of 14 microsatellite markers was applied for genotyping 350 American donkeys from 13 countries. The genetic structure of this metapopulation was analysed using descriptive statistics and Bayesian model-based methods. These populations were then compared to a database containing information on 476 individuals from 11 European breeds to identify the most likely ancestral donor populations. Results showed the presence of two distinct genetic pools, with confluence of the two in Colombia. The southern pool showed a unique genetic signature subsequent to an older founder event, but lacked any significant influence of modern gene flow from Europe. The northern pool, conversely, may have retained more ancestral polymorphisms and/or have experienced modern gene flow from Spanish breeds. The Andalusian and, to a lesser extent, the Catalan breeds have left a more pronounced footprint in some of the American donkey populations analysed.


Assuntos
Equidae/genética , América , Animais , Teorema de Bayes , Equidae/classificação , Variação Genética , Genética Populacional
5.
Anim Genet ; 46(4): 452-6, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26153924

RESUMO

In the course of human migrations, domestic animals often have been translocated to islands with the aim of assuring food availability. These founder events are expected to leave a genetic footprint that may be recognised nowadays. Herewith, we have examined the mitochondrial diversity of goat populations living in the Canarian and Balearic archipelagos. Median-joining network analysis produced very distinct network topologies for these two populations. Indeed, a majority of Canarian goats shared a single ancestral haplotype that segregated in all sampled islands, suggesting a single founder effect followed by a stepping-stone pattern of diffusion. This haplotype also was present in samples collected from archaeological assemblies at Gran Canaria and Lanzarote, making evident its widespread distribution in ancient times. In stark contrast, goats from Majorca and Ibiza did not share any mitochondrial haplotypes, indicating the occurrence of two independent founder events. Furthermore, in Majorcan goats, we detected the segregation of the mitochondrial G haplogroup that has only been identified in goats from Egypt, Iran and Turkey. This finding suggests the translocation of Asian and/or African goats to Majorca, possibly as a consequence of the Phoenician and Carthaginian colonisations of this island.


Assuntos
DNA Mitocondrial/genética , Efeito Fundador , Genética Populacional , Cabras/genética , Animais , Animais Domésticos/genética , Pool Gênico , Deriva Genética , Haplótipos , Ilhas , Dados de Sequência Molecular , Análise de Sequência de DNA , Espanha
6.
Opt Express ; 22(19): 23686-93, 2014 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-25321835

RESUMO

We present a numerical strategy to design fiber based dual pulse light sources exhibiting two predefined spectral peaks in the anomalous group velocity dispersion regime. The frequency conversion is based on the soliton fission and soliton self-frequency shift occurring during supercontinuum generation. The optimization process is carried out by a genetic algorithm that provides the optimum input pulse parameters: wavelength, temporal width and peak power. This algorithm is implemented in a Grid platform in order to take advantage of distributed computing. These results are useful for optical coherence tomography applications where bell-shaped pulses located in the second near-infrared window are needed.


Assuntos
Algoritmos , Simulação por Computador , Tecnologia de Fibra Óptica/instrumentação , Luz , Fótons , Espalhamento de Radiação , Desenho Assistido por Computador , Eletrodos , Desenho de Equipamento
7.
Opt Express ; 22(3): 2451-8, 2014 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-24663536

RESUMO

We propose, by means of numerical simulations, a simple method to design a non-uniform standard single mode fiber to generate spectral broadening in the form of "ad-hoc" chosen peaks from dispersive waves. The controlled multi-peak generation is possible by an on/off switch of Cherenkov radiation, achieved by tailoring the fiber dispersion when decreasing the cladding diameter by segments. The interplay between the fiber dispersion and the soliton self-frequency shift results in discrete peaks of efficiently emitted Cherenkov radiation from low order solitons, despite the small amount of energy contained in a pulse. These spectra are useful for applications that demand low power bell-shaped pulses at specific carrier wavelengths.

8.
Br J Anaesth ; 112(5): 929-35, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24496783

RESUMO

BACKGROUND: Postoperative continuous positive airway pressure (CPAP) can improve lung function. The aim of our study was to assess the efficacy of prophylactic CPAP on the Pa(O2)/FI(O2) ratio measured the day after surgery in patients undergoing lung resection surgery (LRS). METHODS: The study population comprised 110 patients undergoing LRS. On arrival in the postanaesthesia care unit (PACU), patients were randomized to receive CPAP at 5-7 cm H2O during the first 6 h after surgery (CPAP group) or supplemental oxygen through a Venturi mask (Venturi group). The Pa(O2)/FI(O2) ratio was measured on arrival in the PACU, 7 h after admission, and the day after surgery. The Pa(O2)/FI(O2) ratio is the primary endpoint of our study. We also analysed the chest radiograph and assessed the postoperative course. We then analysed the impact of ventilatory management in the PACU depending on the respiratory risk of the patient. RESULTS: Baseline characteristics were similar in both groups. Patients who received CPAP had significantly higher Pa(O2)/FI(O2) at 24 h after surgery compared with patients managed conventionally (Venturi group) (48.6±14 vs 42.3±12, P=0.031), but there were no differences at 7 h. On subgroup analysis, we found that the benefits of CPAP were greater in higher risk patients. The incidence of postoperative pulmonary complications and stay in the PACU and hospital were similar in both groups. CONCLUSIONS: In patients undergoing LRS, prophylactic CPAP during the first 6 h after surgery with a pressure of 5-7 cm H2O improved the Pa(O2)/FI(O2) ratio at 24 h. This effect was more evident in patients with increased risk of postoperative pulmonary complications.


Assuntos
Pressão Positiva Contínua nas Vias Aéreas/métodos , Pulmão/fisiopatologia , Pulmão/cirurgia , Máscaras , Oxigênio/administração & dosagem , Cuidados Pós-Operatórios/métodos , Troca Gasosa Pulmonar/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Desenho de Equipamento , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Adulto Jovem
9.
J Dairy Sci ; 97(11): 7293-7, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25200789

RESUMO

Inferring the breed of origin of dairy products can be achieved through molecular analysis of genetic markers with a population-specific pattern of segregation. The goal of the current work was to generate such markers in goats by resequencing several pigmentation genes [melanocortin 1 receptor (MC1R), v-kit Hardy-Zuckerman 4 feline sarcoma viral oncogene homolog (KIT), tyrosinase (TYR), and tyrosinase-related protein 2 (TYRP2)]. This experiment revealed 10 single nucleotide polymorphisms (SNP), including 5 missense mutations and 1 nonsense mutation. These markers were genotyped in 560 goats from 18 breeds originally from Italy, the Iberian Peninsula, the Canary Islands, and North Africa. Although the majority of SNP segregated at moderate frequencies in all populations (including 2 additional markers that were used as a source of information), we identified a c.764G>A SNP in MC1R that displayed highly divergent allelic frequencies in the Palmera breed compared with the Majorera and Tinerfeña breeds from the Canary Islands. Thus, we optimized a pyrosequencing-based technique that allowed us to estimate, very accurately, the allele frequencies of this marker in complex DNA mixtures from different individuals. Once validated, we applied this method to generating breed-specific DNA profiles that made it possible to detect fraudulent cheeses in which Palmero cheese was manufactured with milk from Majorera goats. One limitation of this approach, however, is that it cannot be used to detect illegal manufacturing where Palmero dairy products are produced by mixing milk from Palmera and Majorera goats, because the c.764G>A SNP segregates in both breeds.


Assuntos
Laticínios/análise , Marcadores Genéticos , Cabras/genética , Receptor Tipo 1 de Melanocortina/metabolismo , Animais , DNA/genética , Frequência do Gene , Genótipo , Mutação de Sentido Incorreto , Polimorfismo de Nucleotídeo Único , Receptor Tipo 1 de Melanocortina/genética , Sensibilidade e Especificidade , Análise de Sequência de DNA
10.
Mar Pollut Bull ; 200: 116087, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38335631

RESUMO

Organotin compounds are persistent pollutants and are considered chemicals of high environmental concern. In the present study, the distribution and degradation of tributyltin were evaluated in field sediments and through an ex situ experiment. For this, sediment samples from two locations were analysed: Luis Piedrabuena Harbour, with higher maritime traffic, and Cerro Avanzado, which receives less impact from anthropogenic activities. The results indicated that pollution levels at Luis Piedrabuena Harbour have decreased compared with studies performed 9 years ago for the same area. On the contrary, traces of organotin compounds have been found for the first time at Cerro Avanzado. Moreover, the butyltin degradation index indicated that organotin compounds undergo an advanced degradation process in the collected samples at both sites. Ex situ experiments revealed a limited capacity of sediments to retain tributyltin, and suggested an active role of bioturbation activity in the degradation of these compounds. In addition, visualisation using chemometric techniques (principal components analysis) allowed a simpler analysis of two sediment characteristics: the degree of contamination and the degradation levels of organotin compounds.


Assuntos
Compostos Orgânicos de Estanho , Compostos de Trialquitina , Poluentes Químicos da Água , Compostos Orgânicos de Estanho/análise , Sedimentos Geológicos/química , Argentina , Poluentes Químicos da Água/análise , Monitoramento Ambiental/métodos , Compostos de Trialquitina/análise
11.
Opt Express ; 21(7): 9132-43, 2013 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-23572002

RESUMO

A numerical investigation of low-order soliton evolution in a proposed seven-cell hollow-core photonic bandgap fiber is reported. In the numerical simulation, we analyze the pulse quality evolution in soliton pulse compression and soliton self-frequency shift in three fiber structures with different cross-section sizes. In the simulation, we consider unchirped soliton pulses (of 400 fs) at the wavelength of 1060 nm. Our numerical results show that the seven-cell hollow-core photonic crystal fiber, with a cross-section size reduction of 2%, promotes the pulse quality on the soliton pulse compression and soliton self-frequency shift. For an input soliton pulse of order 3 (which corresponds to an energy of 1.69 µJ), the pulse gets compressed with a factor of up to 5.5 and a quality factor of 0.73, in a distance of 12 cm. It also experiences a soliton-self frequency shift of up to 28 nm, in a propagation length of 6 m, with a pulse shape quality of ≈ 0.80.


Assuntos
Tecnologia de Fibra Óptica/instrumentação , Refratometria/instrumentação , Ressonância de Plasmônio de Superfície/instrumentação , Desenho de Equipamento , Análise de Falha de Equipamento , Fótons
12.
Nat Genet ; 36(10): 1084-9, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15361874

RESUMO

In T-cell acute lymphoblastic leukemia (T-ALL), transcription factors are known to be deregulated by chromosomal translocations, but mutations in protein tyrosine kinases have only rarely been identified. Here we describe the extrachromosomal (episomal) amplification of ABL1 in 5 of 90 (5.6%) individuals with T-ALL, an aberration that is not detectable by conventional cytogenetics. Molecular analyses delineated the amplicon as a 500-kb region from chromosome band 9q34, containing the oncogenes ABL1 and NUP214 (refs. 5,6). We identified a previously undescribed mechanism for activation of tyrosine kinases in cancer: the formation of episomes resulting in a fusion between NUP214 and ABL1. We detected the NUP214-ABL1 transcript in five individuals with the ABL1 amplification, in 5 of 85 (5.8%) additional individuals with T-ALL and in 3 of 22 T-ALL cell lines. The constitutively phosphorylated tyrosine kinase NUP214-ABL1 is sensitive to the tyrosine kinase inhibitor imatinib. The recurrent cryptic NUP214-ABL1 rearrangement is associated with increased HOX expression and deletion of CDKN2A, consistent with a multistep pathogenesis of T-ALL. NUP214-ABL1 expression defines a new subgroup of individuals with T-ALL who could benefit from treatment with imatinib.


Assuntos
Genes abl , Leucemia-Linfoma de Células T do Adulto/genética , Complexo de Proteínas Formadoras de Poros Nucleares/genética , Plasmídeos/genética , Sequência de Aminoácidos , Fusão Gênica Artificial , Sequência de Bases , Benzamidas , Linhagem Celular Tumoral , Cromossomos Humanos Par 9/genética , DNA de Neoplasias/genética , Inibidores Enzimáticos/uso terapêutico , Amplificação de Genes , Humanos , Mesilato de Imatinib , Hibridização in Situ Fluorescente , Leucemia-Linfoma de Células T do Adulto/tratamento farmacológico , Leucemia-Linfoma de Células T do Adulto/enzimologia , Dados de Sequência Molecular , Piperazinas/uso terapêutico , Proteínas Tirosina Quinases/antagonistas & inibidores , Proteínas Tirosina Quinases/genética , Pirimidinas/uso terapêutico
13.
Radiologia ; 55(6): 514-22, 2013.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-22425358

RESUMO

OBJECTIVE: To present our experience in treating vascular malformations in the oral cavity solely by injecting ethanol into the lesions. MATERIAL AND METHODS: We treated 26 patients (12 men and 14 women) with oral malformations. The diagnosis was based on clinical findings (n=26), magnetic resonance imaging studies (n=19), angiography findings (n=5), and direct puncture venography (n=2). To achieve sclerosis, we administered absolute ethanol through direct puncture. All interventions were performed under deep sedation. RESULTS: The vascular malformations treated ranged from 7mm to 60mm (median: 24.5mm) in maximum diameter and had been present in the oral cavity for 0.2 to 54 years (mean: 13.6 years). The median age of the patients was 44.5 years (range: 12-87 years). The reason for treatment of the malformation was: an increase in size (n=8), local bleeding (n=11), risk of bleeding during dental extraction (n=5), pain (n=1), and esthetic purposes (n=3). Lesions were located in the mucosa of the cheek (n=12), in the facial gingiva (n=5), in the labial mucosa (n=6), in the tongue (n=3), in the pterygomandibular region (n=1), and in the palate (n=1). The median dose of ethanol was 3.2mL. Twenty lesions disappeared after a single injection session, five after two sessions, two after three sessions, and one after five sessions. In 20 cases all signs of the lesions disappeared, in 6 a bluish macule persisted, and in 2 a mass effect persisted. The symptoms improved in all patients. Only transient complications of sclerotherapy were observed: local inflammation, perioral paresthesia in two patients, and necrosis of the mucosa of the cheek in one. CONCLUSIONS: Alcohol sclerotherapy is an efficacious procedure for treating vascular malformations in the oral cavity.


Assuntos
Etanol/administração & dosagem , Boca/irrigação sanguínea , Escleroterapia/métodos , Malformações Vasculares/terapia , Adolescente , Adulto , Idoso , Criança , Feminino , Humanos , Injeções Intralesionais , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
14.
Rev Esp Cir Ortop Traumatol ; 67(3): 193-201, 2023.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-36462726

RESUMO

INTRODUCTION: Proximal humerus fractures are the third most frequent type of fracture in elderly patients. Nowadays, surgical treatment is indicated one third of the time, being the reverse shoulder prosthesis an option especially in complex comminuted patterns. In this study we analyzed the effects of a lateralized reverse prosthesis in tuberosity union and its relationship with the functional results. MATERIAL AND METHODS: Retrospective case study of patients with proximal humerus fractures treated with a lateralized design reverse shoulder prosthesis with one-year minimum follow-up. Tuberosity nonunion was defined as a radiological concept: absence of tuberosity, distance>1cm from the tuberosity fragment to the humeral shaft or tuberosity above the humeral tray. Subgroup analysis was performed, group 1 (n=16) tuberosity union vs. group 2 (n=19) tuberosity nonunion. Groups were compared with the following functional scores: Constant, American Shoulder and Elbow Surgeons and Subjective Shoulder Value. RESULTS: A total of 35 patients were included in this study with a median age of 72.65 years. Postoperative radiographic analysis at one year after surgery revealed a tuberosity nonunion rate of 54%. Subgroup analysis revealed no statistically significant differences in terms of range of motion or functional scores. However, there were differences regarding the Patte sign (p=0.03) which was positive in a larger proportion of patients in the group with tuberosity nonunion. CONCLUSION: Even though there was a large percentage of tuberosity nonunion with the use of a lateralized prosthesis design, patients obtained good results in a similar manner to those found in the union group in terms of range of motion, scores, and patient satisfaction.

15.
Rev Esp Cir Ortop Traumatol ; 67(3): T193-T201, 2023.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-36863524

RESUMO

INTRODUCTION: Proximal humerus fractures are the third most frequent type of fracture in elderly patients. Nowadays, surgical treatment is indicated one third of the time, being the reverse shoulder prosthesis an option especially in complex comminuted patterns. In this study we analyzed the effects of a lateralized reverse prosthesis in tuberosity union and its relationship with the functional results. MATERIAL AND METHODS: Retrospective case study of patients with proximal humerus fractures treated with a lateralized design reverse shoulder prosthesis with one-year minimum follow-up. Tuberosity nonunion was defined as a radiological concept: absence of tuberosity, distance >1cm from the tuberosity fragment to the humeral shaft or tuberosity above the humeral tray. Subgroup analysis was performed, group 1 (n=16) tuberosity union vs. group 2 (n=19) tuberosity nonunion. Groups were compared with the following functional scores: Constant, American Shoulder and Elbow Surgeons and Subjective Shoulder Value. RESULTS: A total of 35 patients were included in this study with a median age of 72.65 years. Postoperative radiographic analysis at one year after surgery revealed a tuberosity nonunion rate of 54%. Subgroup analysis revealed no statistically significant differences in terms of range of motion or functional scores. However, there were differences regarding the Patte sign (p=0.03) which was positive in a larger proportion of patients in the group with tuberosity nonunion. CONCLUSION: Even though there was a large percentage of tuberosity nonunion with the use of a lateralized prosthesis design, patients obtained good results in a similar manner to those found in the union group in terms of range of motion, scores, and patient satisfaction.

16.
Mar Pollut Bull ; 194(Pt B): 115388, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37595454

RESUMO

The influence of the phytoplankton community in the light absorption budget was quantified in coastal waters of the North region of the San Jorge Gulf (Argentinian Patagonia). The phytoplanktonic composition and their absorption spectra were determined. Nanoflagellates and diatoms were the dominant groups. The toxigenic dinoflagellate Dinophysis acuminata was recorded in all the sampling sites. The optical characterization of the particulate material showed that 60 % of the absorption at 443 nm and 88 % of absorption at 675 nm was due to phytoplankton. The contributions of phytoplankton to total absorption at 443 nm wavelengths reached 50 %. The absorption by chromophoric dissolved organic matter (CDOM) and non-algal particles (NAP) was predominant in turbulent waters (>60 %). This study shows the influence of submesoscale physical-biological interactions in the light absorption budget. The field absorption spectra of active optical components are of interest in the assessment and development of regional ocean color satellite algorithms.


Assuntos
Diatomáceas , Dinoflagellida , Fitoplâncton , Algoritmos , Matéria Orgânica Dissolvida
17.
Opt Lett ; 37(20): 4221-3, 2012 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-23073417

RESUMO

We demonstrate that soliplasmons (soliton-plasmon bound states) appear naturally as eigenmodes of nonlinear Maxwell's equations for a metal/Kerr interface. Conservative stability analysis is performed by means of finite element numerical modeling of the time-independent nonlinear Maxwell equations. Dynamical features are in agreement with the presented nonlinear oscillator model.

18.
Biochem Genet ; 49(7-8): 523-32, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21373989

RESUMO

Agouti signaling protein (ASIP) is one of the key players in the modulation of hair pigmentation in mammals. Binding to the melanocortin 1 receptor, ASIP induces the synthesis of phaeomelanin, associated with reddish brown, red, tan, and yellow coats. We have sequenced 2.8 kb of the goat ASIP gene in 48 individuals and identified two missense (Cys126Gly and Val128Gly) and two intronic polymorphisms. In silico analysis revealed that the Cys126Gly substitution may cause a structural change by disrupting a highly conserved disulfide bond. We studied its segregation in 12 Spanish and Italian goat breeds (N = 360) with different pigmentation patterns and found striking differences in the frequency of the putative loss-of-function Gly(126) allele (Italian 0.43, Spanish Peninsular 0.08), but we did not observe a clear association with coat color. This suggests that the frequency of this putative loss-of-function allele has evolved under the influence of demographic rather than selection factors in goats from these two geographical areas.


Assuntos
Proteína Agouti Sinalizadora/genética , Cabras/genética , Cor de Cabelo/genética , Polimorfismo Genético , Substituição de Aminoácidos , Animais , Frequência do Gene , Itália , Espanha
19.
J Appl Physiol (1985) ; 107(1): 34-8, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19390002

RESUMO

We sought to determine the effects of longitudinal loading (artificial gravity) on skeletal muscle protein kinetics in 15 healthy young males after 21 days of 6 degrees head-down tilt bed rest [experimental treatment (Exp) group: n = 8, 31 +/- 1 yr; control (Con) group; n = 7, 28 +/- 1 yr, means +/- SE]. On days 1 and 21 of bed rest, postabsorptive venous blood samples and muscle biopsies (vastus lateralis and soleus) were obtained during a 1-h pulse bolus infusion protocol (0 min, l-[ring-(13)C(6)]phenylalanine, 35 mumol/kg; 30 min, l-[ring-(15)N]phenylalanine, 35 mumol/kg). Outcome measures included mixed muscle fractional synthesis (FSR) and breakdown rates (FBR). The Exp group experienced 1 h of longitudinal loading (2.5G at the feet) via a short-radius centrifuge during each day of bed rest. Mixed muscle FSR in the Con group was reduced by 48.5% (day 1, 0.081 +/- 0.000%/h vs. day 21, 0.042 +/- 0.000%/h; P = 0.001) in vastus lateralis after 21 days of bed rest, whereas the Exp group maintained their rate of protein synthesis. A similar but nonsignificant change in FSR was noted for the soleus muscle (Exp, -7%; Con, -22%). No changes in muscle protein breakdown were observed. In conclusion, 1 h of daily exposure to artificial gravity maintained the rate of protein synthesis of the vastus lateralis and may represent an effective adjunct countermeasure to combat the loss of muscle mass and functional during extended spaceflight.


Assuntos
Gravidade Alterada , Proteínas Musculares/biossíntese , Músculo Esquelético/metabolismo , Atrofia Muscular/prevenção & controle , Transtornos Musculares Atróficos/prevenção & controle , Contramedidas de Ausência de Peso , Adulto , Repouso em Cama/efeitos adversos , Decúbito Inclinado com Rebaixamento da Cabeça/efeitos adversos , Humanos , Masculino , Atrofia Muscular/etiologia , Atrofia Muscular/metabolismo , Transtornos Musculares Atróficos/etiologia , Transtornos Musculares Atróficos/metabolismo , Suporte de Carga/fisiologia , Ausência de Peso/efeitos adversos
20.
Kidney Int ; 73(9): 1054-61, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18288103

RESUMO

Increased demand for amino acids to sustain acute-phase protein synthesis could be the stimulus for the increased muscle protein catabolism during hemodialysis (HD). This could be attenuated by intradialytic amino-acid infusion. To test this, we measured the fractional synthesis rates of albumin, fibrinogen, and muscle protein in eight patients with end-stage renal disease at baseline before dialysis and during HD without or with amino-acid infusion. The percentage change in the fractional synthesis rates of albumin, fibrinogen, and muscle protein from baseline was significantly higher during HD with amino-acid infusion than without amino-acid infusion. Leg muscle proteolysis was significantly increased during unsupplemented HD compared with baseline, but this was not decreased by amino-acid infusion. Arteriovenous balance studies across the leg showed a net efflux of interleukin-6 (IL-6) from the muscle into the vein during HD. The fractional synthesis rate of albumin, fibrinogen, and muscle protein correlated with each other and with the IL-6 efflux from the leg. Leg muscle protein catabolism was positively related to IL-6 release from the leg and not associated with amino-acid availability. Our results show that intradialytic cytokine activation and not amino-acid depletion is the major protein catabolic signal during HD.


Assuntos
Albuminas/biossíntese , Fibrinogênio/biossíntese , Interleucina-6/fisiologia , Falência Renal Crônica/metabolismo , Falência Renal Crônica/terapia , Rim/metabolismo , Proteínas Musculares/biossíntese , Diálise Renal , Adulto , Aminoácidos/farmacologia , Citocinas/fisiologia , Feminino , Humanos , Masculino
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