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1.
Ann Oncol ; 30(8): 1298-1303, 2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-31192355

RESUMO

BACKGROUND: This trial evaluated whether preoperative short-course radiotherapy and consolidation chemotherapy (CCT) were superior to chemoradiation in rectal cancers with clinical (c)T4 or fixed cT3. Previously, we reported early results showing no differences in the radical surgery rate (primary end point). In the short-course/CCT group, we observed lower acute toxicity of preoperative treatment and better overall survival (OS). We updated results to determine whether the benefit in OS was sustained and to evaluate late complications. PATIENTS AND METHODS: Patients with cT4 or fixed cT3 rectal cancer were randomized either to preoperative 5 × 5 Gy and three cycles of FOLFOX4 or to chemoradiation (50.4 Gy with bolus 5-Fu, leucovorin and oxaliplatin). RESULTS: Patients (N = 515) were eligible for analysis, 261 in the short-course/CCT group and 254 in the chemoradiation group. The median follow-up was 7.0 years. The difference in OS was insignificant [hazard ratio (HR) 0.90; 95% confidence interval (CI) 0.70-1.15; P = 0.38). However, the difference in early OS favouring short-course/CCT previously reported was observed again, being 9% at 3 years (95% CI 0.5% to 17%). This difference disappeared later; at 8 years OS was 49% in both groups. There was no difference in disease-free survival (HR 0.95; 95% CI 0.75-1.19; P = 0.65) at 8 years 43% versus 41% in the short-course/CCT group versus the chemoradiation group, respectively. The corresponding values for cumulative incidences of local failure and distant metastases did not differ and were HR = 1.08, 95% CI 0.70-1.23, P = 0.60, 35% versus 32% and HR = 1.10, 95% CI 0.68-1.23, P = 0.54, 36% versus 34%, respectively. The rate of late complications was similar (P = 0.66), grade 3+ being 11% versus 9% in the short-course/CCT group versus the chemoradiation group, respectively. CONCLUSION: The superiority of preoperative short-course/CCT over chemoradiation was not demonstrated. CLINICAL TRIAL NUMBER: The trial is registered as ClinicalTrials.gov number NCT00833131.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Fracionamento da Dose de Radiação , Terapia Neoadjuvante/métodos , Recidiva Local de Neoplasia/epidemiologia , Neoplasias Retais/terapia , Adolescente , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Quimiorradioterapia/efeitos adversos , Quimiorradioterapia/métodos , Quimioterapia de Consolidação/efeitos adversos , Quimioterapia de Consolidação/métodos , Intervalo Livre de Doença , Feminino , Fluoruracila/administração & dosagem , Fluoruracila/efeitos adversos , Seguimentos , Humanos , Incidência , Leucovorina/administração & dosagem , Leucovorina/efeitos adversos , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante/efeitos adversos , Recidiva Local de Neoplasia/prevenção & controle , Compostos Organoplatínicos/administração & dosagem , Compostos Organoplatínicos/efeitos adversos , Polônia/epidemiologia , Protectomia , Neoplasias Retais/mortalidade , Neoplasias Retais/patologia , Reto/efeitos dos fármacos , Reto/patologia , Reto/efeitos da radiação , Reto/cirurgia , Fatores de Tempo , Adulto Jovem
2.
Kidney Blood Press Res ; 40(3): 323-34, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26067851

RESUMO

UNLABELLED: Background/Aims . High salt (HS) intake may elevate blood pressure (BP), also in animals without genetic salt sensitivity. The development of salt-dependent hypertension could be mediated by endogenous vasoactive agents; here we examined the role of vasodilator epoxyeicosatrienoic acids (EETs) and vasoconstrictor 20-hydroxyeicosatetraenoic acid (20-HETE). METHODS: In conscious Wistar rats on HS diet systolic BP (SBP) was examined after chronic elevation of EETs using 4-[4-(3-adamantan-1-yl-ureido)-cyclohexyloxy]-benzoic acid (c-AUCB), a blocker of soluble epoxide hydrolase, or after inhibition of 20-HETE with 1-aminobenzotriazole (ABT). Thereafter, in acute experiments the responses of renal artery blood flow (Transonic probe) and renal regional perfusion (laser-Doppler) to intrarenal acetylcholine (ACh) or norepinephrine were determined. RESULTS: HS diet increased urinary 20-HETE excretion. The SBP increase was not reduced by c-AUCB but prevented by ABT until day 5 of HS exposure. Renal vasomotor responses to ACh or norepinephrine were similar on standard and HS diet. ABT but not c-AUCB abolished the responses to ACh. Conclusions . 20-HETE seems to mediate the early-phase HS diet-induced BP increase while EETs are not engaged in the process. Since HS exposure did not alter renal vasodilator responses to Ach, endothelial dysfunction is not a critical factor in the mechanism of salt-induced blood pressure elevation.


Assuntos
Pressão Sanguínea/efeitos dos fármacos , Ácidos Hidroxieicosatetraenoicos/metabolismo , Circulação Renal/efeitos dos fármacos , Sódio na Dieta/efeitos adversos , Acetilcolina/metabolismo , Animais , Pressão Arterial , Epóxido Hidrolases/sangue , Ácidos Hidroxieicosatetraenoicos/antagonistas & inibidores , Masculino , Óxido Nítrico/fisiologia , Norepinefrina/metabolismo , Concentração Osmolar , Ratos , Ratos Wistar , Triazóis/farmacologia
3.
Phys Rev Lett ; 113(6): 067003, 2014 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-25148345

RESUMO

Proximity-induced superconductivity in a 3D topological insulator represents a new avenue for observing zero-energy Majorana fermions inside vortex cores. Relatively small gaps and low transition temperatures of conventional s-wave superconductors put hard constraints on these experiments. Significantly larger gaps and higher transition temperatures in cuprate superconductors might be an attractive alternative to considerably relax these constraints, but it is not clear whether the proximity effect would be effective in heterostructures involving cuprates and topological insulators. Here, we present angle-resolved photoemission studies of thin Bi(2)Se(3) films grown in situ on optimally doped Bi(2)Sr(2)CaCu(2)O(8+δ) substrates that show the absence of proximity-induced gaps on the surfaces of Bi(2)Se(3) films as thin as a 1.5 quintuple layer. These results suggest that the superconducting proximity effect between a cuprate superconductor and a topological insulator is strongly suppressed, likely due to a very short coherence length along the c axis, incompatible crystal and pairing symmetries at the interface, small size of the topological surface state's Fermi surface, and adverse effects of a strong spin-orbit coupling in the topological material.

4.
Biol Sport ; 31(1): 9-14, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24917684

RESUMO

The aim of this study was to examine the chronic effects of single and repeated jumps training on vertical landing force (VGRF) and jump height in untrained men. The VGRF and jump height were compared after a six-week plyometric training programme containing single and repeated jumps, together with two additional parameters: landing time (LT) and range of the knee flexion during landing (KF). Thirty-six untrained physical education students with a plyometric training background were randomly assigned to a single jump group (SJG, n =12), repeated jumps group (RJG, n =12), and control group (CON, n =12). The SJG performed only single jumps, the RJG executed repeated (consecutive) jumps, whereas the CON did not perform any exercises at all. A countermovement jump (CMJ), repeated countermovement jumps (RCMJ), and a drop jump (DJ) were tested before and after the training. Only the RJG showed a significantly reduced VGRF (p < 0.05) in all tests. Both plyometric groups significantly improved (p < 0.05) their jump height in all tests. The LT was significantly greater in the RJG, compared to the SJG, in all tests. The KF was also significantly (p < 0.05) greater in the RJG than in the SJG for CMJ and RCMJ. The results suggest that repeated jumps are beneficial for simultaneous landing force reduction and jumping performance enhancement.

5.
J Physiol Pharmacol ; 75(1)2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38583435

RESUMO

Endothelins and renal dopamine contribute to control of renal function and arterial pressure in health and various forms of experimental hypertension, the action is mediated by tonic activity of specific receptors. We determined the action mediated by endothelin type B and by dopamine D3 receptors (ETB-R, D3-R) in anaesthetized spontaneously hypertensive (SHR) and in deoxycorticosterone acetate (DOCA)-salt hypertensive rats. In rats of both hypertension models infused during 60 min into the interstitium of in situ kidney were either ETB-R antagonist, BQ788 (0.67 mg kg-1 BW h-1) or D3-R antagonist, GR103691 (0.2 mg kg-1 BW h-1). Arterial pressure (MAP), renal artery blood flow (RBF, transonic probe) and renal medullary blood flow (MBF, laser-Doppler) were measured along with sodium, water and total solute excretion (UNaV, V, UosmV). Experiments with ETB-R blockade confirmed their tonic vasodilator action in the whole kidney (RBF) and medulla (MBF) in both hypertension models. In SHR only, the first evidence was provided that ETB-R specifically increases transtubular backflux of non-electrolyte solutes. In DOCA-salt rats ETB-R blockade caused an early decrease in water and salt transport whereas an increase was often reported from many previous studies. The most striking effect of D3-R blockade in SHR was a selective increase in MBF, which strongly suggested tonic vasoconstrictor action of these receptors in the renal medulla; this speaks against prevailing opinion that D3 receptors are virtually inactive in SHR. In our model variant of DOCA-salt rats of D3-R blockade clearly caused a rapid major increase in MAP in parallel with depression of renal haemodynamics.


Assuntos
Acetato de Desoxicorticosterona , Hipertensão , Ratos , Animais , Receptores de Dopamina D3 , Acetato de Desoxicorticosterona/farmacologia , Antagonistas dos Receptores de Endotelina/farmacologia , Ratos Endogâmicos SHR , Hipertensão/induzido quimicamente , Endotelinas/farmacologia , Água , Acetatos/farmacologia , Pressão Sanguínea , Endotelina-1
6.
Physiol Res ; 73(1): 9-25, 2024 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-38466001

RESUMO

No information is available about sex-related differences in unloading-induced cardiac atrophy. We aimed to compare the course of unloading-induced cardiac atrophy in intact (without gonadectomy) male and female rats, and in animals after gonadectomy, to obtain insight into the influence of sex hormones on this process. Heterotopic heart transplantation (HT((x)) was used as a model for heart unloading. Cardiac atrophy was assessed as the weight ratio of heterotopically transplanted heart weight (HW) to the native HW on days 7 and 14 after HTx in intact male and female rats. In separate experimental groups, gonadectomy was performed in male and female recipient animals 28 days before HT(x) and the course of cardiac atrophy was again evaluated on days 7 and 14 after HT(x). In intact male rats, HT(x) resulted in significantly greater decreases in whole HW when compared to intact female rats. The dynamics of the left ventricle (LV) and right ventricle (RV) atrophy after HT(x) was quite similar to that of whole hearts. Gonadectomy did not have any significant effect on the decreases in whole HW, LV, and RV weights, with similar results in male and female rats. Our results show that the development of unloading-induced cardiac atrophy is substantially reduced in female rats when compared to male rats. Since gonadectomy did not alter the course of cardiac atrophy after HTx, similarly in both male and female rats, we conclude that sex-linked differences in the development of unloading-induced cardiac atrophy are not caused by the activity of sex hormones.


Assuntos
Transplante de Coração , Coração , Feminino , Masculino , Animais , Ratos , Transplante de Coração/efeitos adversos , Transplante de Coração/métodos , Ventrículos do Coração/patologia , Atrofia/patologia , Hormônios Esteroides Gonadais , Miocárdio/patologia
7.
Appl Environ Microbiol ; 79(2): 734-7, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23144142

RESUMO

In a comparison to the widely used Cronobacter rpoB PCR assay, a highly specific multiplexed PCR assay based on cgcA, a diguanylate cyclase gene, that identified all of the targeted six species among 305 Cronobacter isolates was designed. This assay will be a valuable tool for identifying suspected Cronobacter isolates from food-borne investigations.


Assuntos
Técnicas Bacteriológicas/métodos , Cronobacter/classificação , Cronobacter/genética , Proteínas de Escherichia coli/genética , Reação em Cadeia da Polimerase Multiplex/métodos , Fósforo-Oxigênio Liases/genética , Cronobacter/enzimologia , Cronobacter/isolamento & purificação , Microbiologia de Alimentos , Doenças Transmitidas por Alimentos/diagnóstico , Doenças Transmitidas por Alimentos/microbiologia , Sensibilidade e Especificidade
8.
Front Immunol ; 14: 1110292, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36999035

RESUMO

Human leukocyte antigen (HLA) molecular mismatch is a powerful biomarker of rejection. Few studies have explored its use in assessing rejection risk in heart transplant recipients. We tested the hypothesis that a combination of HLA Epitope Mismatch Algorithm (HLA-EMMA) and Predicted Indirectly Recognizable HLA Epitopes (PIRCHE-II) algorithms can improve risk stratification of pediatric heart transplant recipients. Class I and II HLA genotyping were performed by next-generation sequencing on 274 recipient/donor pairs enrolled in the Clinical Trials in Organ Transplantation in Children (CTOTC). Using high-resolution genotypes, we performed HLA molecular mismatch analysis with HLA-EMMA and PIRCHE-II, and correlated these findings with clinical outcomes. Patients without pre-formed donor specific antibody (DSA) (n=100) were used for correlations with post-transplant DSA and antibody mediated rejection (ABMR). Risk cut-offs were determined for DSA and ABMR using both algorithms. HLA-EMMA cut-offs alone predict the risk of DSA and ABMR; however, if used in combination with PIRCHE-II, the population could be further stratified into low-, intermediate-, and high-risk groups. The combination of HLA-EMMA and PIRCHE-II enables more granular immunological risk stratification. Intermediate-risk cases, like low-risk cases, are at a lower risk of DSA and ABMR. This new way of risk evaluation may facilitate individualized immunosuppression and surveillance.


Assuntos
Antígenos HLA , Transplante de Coração , Humanos , Criança , Teste de Histocompatibilidade , Antígenos HLA/genética , Doadores de Tecidos , Anticorpos , Epitopos , Antígenos de Histocompatibilidade Classe II , Transplante de Coração/efeitos adversos , Medição de Risco
9.
Eur J Vasc Endovasc Surg ; 43(5): 588-93, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22436266

RESUMO

OBJECTIVE: Folic acid (FA) administration can reduce plasma total homocysteine (tHcy); however, it fails to decrease cardiovascular events and progression of peripheral artery disease (PAD). Nɛ-homocysteinyl-lysine isopeptide (Nɛ-Hcy-Lys) is formed during catabolism of homocysteinylated proteins. We sought to investigate factors that determine the presence of Nɛ-Hcy-Lys in PAD patients with hyperhomocysteinemia receiving FA. PATIENTS AND METHODS: We studied 131 consecutive PAD patients with tHcy > 15 µmol l(-1) taking FA 0.4 mg d(-1) for 12 months. Serum Nɛ-Hcy-Lys was determined by high-performance liquid chromatography (HPLC). We also measured interleukin-6 (IL-6), plasminogen activator inhibitor-1 (PAI-1), asymmetric dimethylarginine (ADMA) and 8-iso-prostaglandin F(2α) (8-iso-PGF(2α)). RESULTS: FA administration resulted in a 70.5% decrease in tHcy (p < 0.0001). However, serum Nɛ-Hcy-Lys was detectable in 28 (21.4%) patients on FA who were more frequently current smokers and survivors of ischaemic stroke (p < 0.001). They had higher tHcy by 46.0%, PAI-1 by 51.7%, 8-iso-PGF(2α) by 59.1% and ADMA by 26.4% (all, p < 0.0001). The presence of Nɛ-Hcy-Lys was associated with lower ankle-brachial index (ABI) values (p < 0.001) and higher prevalence of cardiovascular events (p < 0.001) following therapy. CONCLUSION: The presence of Nɛ-Hcy-Lys in one-fifth of hyperhomocysteinemic individuals with PAD despite FA treatment is associated with progression of PAD and with increased ADMA formation, oxidative stress and hypofibrinolysis.


Assuntos
Homocisteína/metabolismo , Hiper-Homocisteinemia/metabolismo , Peptídeos/metabolismo , Doença Arterial Periférica/fisiopatologia , Proteínas/metabolismo , Complexo Vitamínico B/administração & dosagem , Idoso , Progressão da Doença , Feminino , Ácido Fólico/administração & dosagem , Homocisteína/sangue , Humanos , Hiper-Homocisteinemia/sangue , Hiper-Homocisteinemia/tratamento farmacológico , Masculino , Metabolismo , Pessoa de Meia-Idade , Estresse Oxidativo , Peptídeos/sangue , Doença Arterial Periférica/sangue , Doença Arterial Periférica/metabolismo
10.
J Nanosci Nanotechnol ; 12(11): 8721-4, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23421273

RESUMO

Granular GaAs:(Mn, Ga)As films were prepared by annealing at 500 degrees C under ambient and enhanced hydrostatic pressure (1.1 GPa), of Ga(1-x)Mn(x)As/GaAs layers (x = 0.025, 0.03, 0.04, 0.05 and 0.063) grown by molecular beam epitaxy method at 230 degrees C. Layers were fully strained in respect to the substrate before and after treatment. Strain change, from compressive to tensile, related to creation of MnAs inclusions of zinc blende structure, was detected after sample annealing. Mn concentration remained unchanged after annealing under ambient and enhanced hydrostatic pressure. Distinct influence of hydrostatic pressure applied during annealing on strain as well as on interface roughness has been found.


Assuntos
Ligas/química , Gálio/química , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Módulo de Elasticidade , Dureza , Substâncias Macromoleculares/química , Teste de Materiais , Conformação Molecular , Tamanho da Partícula , Estresse Mecânico , Propriedades de Superfície
11.
J Nanosci Nanotechnol ; 12(6): 4868-73, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22905543

RESUMO

We explore the magnetic anisotropy of GaMnAs ferromagnetic semiconductor by Planar Hall Effect (PHE) measurements. Using low magnitude of applied magnetic field (i.e., when the magnitude H is smaller than both cubic Hc and uniaxial Hu anisotropy field), we have observed various shapes of applied magnetic field direction dependence of Planar Hall Resistance (PHR). In particular, in two regions of temperature. At T < Tc/2, the "square-shape" signal and at T > Tc/2 the "zigzag-shape" signal of PHR. They reflect different magnetic anisotropy and provide information about magnetization reversal process in GaMnAs ferromagnetic semiconductor. The theoretical model calculation of PHR based on the free energy density reproduces well the experimental data. We report also the temperature dependence of anisotropy constants and magnetization orientations. The transition of easy axis from biaxial to uniaxiale axes has been observed and confirmed by SQUID measurements.


Assuntos
Nanopartículas Metálicas/química , Modelos Químicos , Semicondutores , Anisotropia , Simulação por Computador , Magnetismo , Teste de Materiais , Temperatura
12.
J Sports Med Phys Fitness ; 52(3): 319-27, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22648471

RESUMO

AIM: The purpose of this study was to examine how focusing attention during nine weeks of plyometric training influence jumping performance. It was hypothesized that participants utilizing an external focus of attention during practice would produce greater improvements in jumping behavior compared to participants practicing in the internal and control conditions. METHODS: Thirty-six untrained but physically active male college students were randomly assigned to 1 of 3 plyometric groups with a different focus of attention: external (EXF; N.=12), internal (INF; N.=12), and control (CON; N.=12). All participants subsequently participated in the same an 9-week periodized training program. Standing long jump (SLJ), countermovement jump (CMJ) and drop jump (DJ) were tested pre- and posttraining intervention. RESULTS: The EXF group exhibited greater improvement (P<0.05) in jumping distance for SLJ and height for CMJ than both the INF and CON groups, while the enhancement in jumping height for DJ was not superior (P<0.05) in the EXF group in comparison with the INF and CON groups. However, the CON group showed a greater increase (P<0.05) in jumping height for DJ than the INF group. The EXF group increased the range of knee flexion (KF), whereas both the INF and CON groups decreased the KF during the CMJ. Additionally, only the CON group reduced KF during the execution of the DJ. The EXF group (P<0.05) increased contact time, whereas both the INF and CON groups decreased (P<0.05) contact time in DJ. The EXF group had significantly (P<0.05) greater vertical ground reaction force in CMJ and DJ when compared with the INF and CON groups. CONCLUSION: These results suggest that the external focus of attention during plyometric training may provide a greater stimulus to jump performance in slow stretch shortening cycle (SSC) tasks by producing greater force than adopting the internal and no specific focus.


Assuntos
Desempenho Atlético/fisiologia , Atenção , Educação Física e Treinamento/métodos , Exercício Pliométrico , Análise de Variância , Humanos , Masculino , Destreza Motora/fisiologia , Movimento/fisiologia , Adulto Jovem
13.
Fish Physiol Biochem ; 38(6): 1645-1653, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22660840

RESUMO

The analysis of the tench growth hormone gene structure revealed a comparable organization of coding and non-coding regions than other from cyprinid species. Based on the performed mRNA and amino acid sequence alignments, gh tench is related to Asian than to European representatives of Cyprinidae family. Second aim of the work was to characterize and predict protein structure of the tench growth hormone. Tinca tinca GH share many common features with human GH molecule. The Tench GH protein binds to the growth hormone receptor (GHR) using two regions I and II that are situated at opposite sites of molecule. Binding site I is placed in the central part of T. tinca GH and H 189 amino acid in the middle region of the IV helix is crucial for GH-GHR interactions.


Assuntos
Cyprinidae/metabolismo , Hormônio do Crescimento/metabolismo , Animais , Sequência de Bases , DNA/genética , Regulação da Expressão Gênica/fisiologia , Hormônio do Crescimento/genética , Modelos Moleculares , Dados de Sequência Molecular , Conformação Proteica
14.
Appl Environ Microbiol ; 77(12): 4017-26, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21531829

RESUMO

Cronobacter (formerly Enterobacter sakazakii) is a recently defined genus consisting of six species, C. sakazakii, C. malonaticus, C. dublinensis, C. muytjensii, C. turicensis, and Cronobacter genomospecies 1. In this study, MboII restriction fragment length polymorphism (RFLP) patterns of O-antigen gene clusters, located between galF and gnd, were used to identify serotypes in Cronobacter spp. Seven O-antigen RFLP clusters were generated, including three C. sakazakii clusters, previously identified as serotypes O1, O2, and O3. The O-antigen regions of six strains with unique RFLP patterns, including two C. sakazakii strains, two C. malonaticus strains, one C. turicensis strain, and one C. muytjensii strain, revealed three O-antigen gene clusters shared among Cronobacter species. PCR assays were developed, targeting the wzx O-antigen polymerase gene, and used to screen 231 Cronobacter strains to determine the frequency of these newly identified serotypes.


Assuntos
Técnicas Bacteriológicas/métodos , Enterobacteriaceae/classificação , Enterobacteriaceae/genética , Família Multigênica , Antígenos O/genética , Reação em Cadeia da Polimerase/métodos , Análise por Conglomerados , Primers do DNA/genética , DNA Bacteriano/química , DNA Bacteriano/genética , Enterobacteriaceae/isolamento & purificação , Infecções por Enterobacteriaceae/microbiologia , Microbiologia Ambiental , Microbiologia de Alimentos , Dados de Sequência Molecular , Polimorfismo de Fragmento de Restrição , Análise de Sequência de DNA
15.
Appl Environ Microbiol ; 77(10): 3255-67, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21421789

RESUMO

Cronobacter spp. are emerging neonatal pathogens that cause meningitis, sepsis, and necrotizing enterocolitis. The genus Chronobacter consists of six species: C. sakazakii, C. malonaticus, C. muytjensii, C. turicensis, C. dublinensis, and Cronobacter genomospecies group 1. Whole-genome sequencing of C. sakazakii BAA-894 and C. turicensis z3032 revealed that they harbor similarly sized plasmids identified as pESA3 (131 kb) and pCTU1 (138 kb), respectively. In silico analysis showed that both plasmids encode a single RepFIB-like origin of replication gene, repA, as well as two iron acquisition systems (eitCBAD and iucABCD/iutA). In a chrome azurol S agar diffusion assay, it was demonstrated that siderophore activity was associated with the presence of pESA3 or pCTU1. Additionally, pESA3 contains a cpa (Cronobacter plasminogen activator) gene and a 17-kb type 6 secretion system (T6SS) locus, while pCTU1 contains a 27-kb region encoding a filamentous hemagglutinin gene (fhaB), its specifc transporter gene (fhaC), and associated putative adhesins (FHA locus), suggesting that these are virulence plasmids. In a repA-targeted PCR assay, 97% of 229 Cronobacter species isolates were found to possess a homologous RepFIB plasmid. All repA PCR-positive strains were also positive for the eitCBAD and iucABCD/iutA iron acquisition systems. However, the presence of cpa, T6SS, and FHA loci depended on species, demonstrating a strong correlation with the presence of virulence traits, plasmid type, and species. These results support the hypothesis that these plasmids have evolved from a single archetypical plasmid backbone through the cointegration, or deletion, of specific virulence traits in each species.


Assuntos
Enterobacteriaceae/genética , Plasmídeos , Fatores de Virulência/genética , Análise por Conglomerados , Meios de Cultura/química , DNA Helicases/genética , DNA Bacteriano/química , DNA Bacteriano/genética , Enterobacteriaceae/metabolismo , Ferro/metabolismo , Proteínas de Membrana Transportadoras/genética , Dados de Sequência Molecular , Filogenia , Análise de Sequência de DNA , Sideróforos/genética , Sideróforos/metabolismo , Transativadores/genética , Fatores de Virulência/metabolismo
16.
Food Chem Toxicol ; 152: 112197, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33864840

RESUMO

Declines across global fishery stocks forced aquaculture feed manufacturers to search for new and sustainable components. Therefore, the aim of study was assessing nutritional value and sensory properties of meat of common carp (Cyprinus carpio L.) fed for 116 days with two blends. The control feed contained 5% of fishmeal and vegetable oils (rapeseed and soybean) as sole fat sources. While in the experimental diet half of the fishmeal was replaced with a blend of microalgae (Spirulina sp., Chlorella sp.), macroalgae (Laminaria digitata) and vegetable oil was replaced with salmon oil. Proximate composition, energy value, fatty acid profile of meat, nutritional characteristics of fat and protein as well as culinary properties of fillets were assessed. Fillets of carp fed experimental diet had a higher level of protein, lower level of fat and energy value. Intramuscular fat of fish fed with the experimental diet had a better parameters of quality. Protein in the meat of fish from both groups was characterized by a high quality comparing to the protein standard. Our study showed that meat of carp fed with experimental feed enriched with sustainable and natural feed ingredients can be a sensorily attractive source of nutritious ingredients in the human diet.


Assuntos
Ração Animal , Carpas/metabolismo , Produtos Pesqueiros/análise , Valor Nutritivo , Animais , Óleos de Peixe/metabolismo , Proteínas de Peixes/análise , Humanos , Microalgas/metabolismo , Odorantes/análise , Salmão , Alga Marinha/metabolismo , Paladar , Triglicerídeos/análise
17.
J Fish Dis ; 33(3): 267-72, 2010 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-20102462

RESUMO

Hybrids of koi, Cyprinus carpio x crucian carp, Carassius carassius and koi x goldfish, Carassius auratus, proved to be susceptible to koi herpesvirus (KHV, syn. CyHV-3) and developed KHV disease (KHVD). While hybrids of koi x goldfish were partly resistant to mortality following infection by immersion, most koi x crucian carp hybrids died after bath infection. KHV DNA was detected in dead fish but also in all surviving animals by different polymerase chain reactions (PCRs). According to these results, hybrid crossbreeding does not seem to prevent severe losses associated with KHV in terms of inducing KHVD. The present study showed severe losses after a waterborne KHV infection of between 35% and 100% in koi x goldfish and koi x crucian carp hybrids as well as in SPF carp.


Assuntos
Cruzamento , Carpas/imunologia , Suscetibilidade a Doenças/veterinária , Doenças dos Peixes/imunologia , Infecções por Herpesviridae/veterinária , Animais , Carpas/virologia , Doenças dos Peixes/mortalidade , Doenças dos Peixes/patologia , Doenças dos Peixes/virologia , Herpesviridae/fisiologia , Infecções por Herpesviridae/imunologia , Infecções por Herpesviridae/mortalidade , Infecções por Herpesviridae/patologia , Análise de Sobrevida
18.
Nano Lett ; 9(7): 2654-60, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19505134

RESUMO

The electronic structure of epitaxial monolayer, bilayer, and trilayer graphene on Ru(0001) was determined by selected-area angle-resolved photoelectron spectroscopy (micro-ARPES). Micro-ARPES band maps provide evidence for a strong electronic coupling between monolayer graphene and the adjacent metal, which causes the complete disruption of the graphene pi-bands near the Fermi energy. However, the perturbation by the metal decreases rapidly with the addition of further graphene sheets, and already an epitaxial graphene bilayer on Ru recovers the characteristic Dirac cones of isolated monolayer graphene. A graphene trilayer on Ru behaves like free-standing bilayer graphene. Density-functional theory based calculations show that this decoupling is due to the efficient passivation of metal d-states by the interfacial graphene layer.


Assuntos
Grafite/química , Teoria Quântica , Rutênio/química , Eletrônica , Grafite/classificação , Modelos Químicos , Propriedades de Superfície
19.
Food Chem Toxicol ; 140: 111300, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32224215

RESUMO

Demand for omega-3 long chain polyunsaturated fatty acids has become global challenge for aquaculture and different components have been used to increase nutritional value of fillets. The aim of this study was to evaluate influences of feeds on zootechnical parameters, biochemical plasma parameters, expression of lipid-dependent genes, hepatocyte histomorphologies, and fatty acid profiles in common carp fillets. We compared a control diet (CTRL), mimicking a commercial feed formulation for common carp, with three diets containing blends of vegetable oils and a DHA-rich alga (Schizochytrium sp.) included at 3.125% (CB1) or 1.563% (CB2), and 2.1% salmon oil (CB3). The study revealed no differences in final body weight of fish fed CB1-3 diets in comparison with significantly lower CTRL. Concentrations of all biochemical parameters in plasma increased gradually in fish fed CB1-3 diets when compared to CTRL diet, with exception of triacylglycerol levels. Expression of hepatic fas, elovl-5a and pparα genes increased significantly in fish fed CB1 and CB2. Additionally, eicosapentaenoic (EPA) and docosahexaenoic acid (DHA) accumulation in muscle tissue was directly proportional to the amounts supplied in the diets. Our study revealed that carp fillet profiles can be manipulated for DHA and EPA-contents using enriched diets, depending on the source of fat.


Assuntos
Ração Animal/análise , Carpas/sangue , Gorduras na Dieta/administração & dosagem , Expressão Gênica , Fígado/patologia , Animais , Carpas/genética , Ácidos Graxos/análise , Lipídeos/sangue
20.
Food Chem Toxicol ; 139: 111261, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32198031

RESUMO

The effect of carp feeding with n-3 PUFA-enriched feed (Schizochytrium sp. meal or salmon oil) on nutritional quality indicators (proximal composition, fatty acid profile of fat) and culinary quality (color parameters, texture, sensory properties) was evaluated. Highly significant effects of carp nutrition on chemical composition and fat characteristics, L* and a* color parameters, muscle fiber size, endomysium thickness, moisture and taste of fillets were determined. Fillets obtained from carps fed with the experimental feed contained less protein and more crude fat and had larger muscle fibers, but scored more highly in the sensory evaluation of moisture and fishy taste. In the fat of carp fed the enriched feed, a greater share of total PUFA, n-3 PUFA, total EPA and DHA, n-3/n-6 ratio, and a smaller share of total MUFA were observed compared with control fish. However, no effect of nutrition on the texture of carp fillets, assessed either instrumentally or using sensory methods, was found. The use of Schizochytrium sp. meal as a source of EPA and DHA gave much better results than salmon oil, as it allowed a higher content of these valuable fatty acids to be achieved, without compromising quality.


Assuntos
Carpas/metabolismo , Ácidos Graxos Ômega-3/análise , Alimentos Marinhos/análise , Ração Animal/análise , Animais , Cor , Ácidos Docosa-Hexaenoicos/administração & dosagem , Ácidos Docosa-Hexaenoicos/análise , Ácido Eicosapentaenoico/administração & dosagem , Ácido Eicosapentaenoico/análise , Ácidos Graxos Ômega-3/administração & dosagem , Óleos de Peixe/administração & dosagem , Óleos de Peixe/análise , Humanos , Fibras Musculares Esqueléticas/metabolismo , Valor Nutritivo , Odorantes/análise , Melhoria de Qualidade , Paladar
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