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1.
Mol Phylogenet Evol ; 195: 108046, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38447924

RESUMO

The global decline of freshwater mussels and their crucial ecological services highlight the need to understand their phylogeny, phylogeography and patterns of genetic diversity to guide conservation efforts. Such knowledge is urgently needed for Unio crassus, a highly imperilled species originally widespread throughout Europe and southwest Asia. Recent studies have resurrected several species from synonymy based on mitochondrial data, revealing U. crassus to be a complex of cryptic species. To address long-standing taxonomic uncertainties hindering effective conservation, we integrate morphometric, phylogenetic, and phylogeographic analyses to examine species diversity within the U. crassus complex across its entire range. Phylogenetic analyses were performed using cytochrome c oxidase subunit I (815 specimens from 182 populations) and, for selected specimens, whole mitogenome sequences and Anchored Hybrid Enrichment (AHE) data on âˆ¼ 600 nuclear loci. Mito-nuclear discordance was detected, consistent with mitochondrial DNA gene flow between some species during the Pliocene and Pleistocene. Fossil-calibrated phylogenies based on AHE data support a Mediterranean origin for the U. crassus complex in the Early Miocene. The results of our integrative approach support 12 species in the group: the previously recognised Unio bruguierianus, Unio carneus, Unio crassus, Unio damascensis, Unio ionicus, Unio sesirmensis, and Unio tumidiformis, and the reinstatement of five nominal taxa: Unio desectusstat. rev., Unio gontieriistat. rev., Unio mardinensisstat. rev., Unio nanusstat. rev., and Unio vicariusstat. rev. Morphometric analyses of shell contours reveal important morphospace overlaps among these species, highlighting cryptic, but geographically structured, diversity. The distribution, taxonomy, phylogeography, and conservation of each species are succinctly described.


Assuntos
Unio , Animais , Filogenia , Filogeografia , Unio/genética , Europa (Continente) , DNA Mitocondrial/genética , Variação Genética
5.
RSC Adv ; 8(26): 14713-14721, 2018 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-35540740

RESUMO

Polyamide 6/modified silica composite materials have been prepared by a coupled polymerization procedure. For this purpose, the three-component-system we presented in a previous publication, consisting of ε-aminocaproic acid (ε-ACA), ε-caprolactam (ε-CL), and 1,1',1'',1'''-silanetetrayltetrakis-(azepan-2-one) (Si(ε-CL)4), has been combined with other silicon monomers with one or two methyl groups (MeSi(ε-CL)3 and Me2Si(ε-CL)2). The simultaneous polymerization of ε-CL and silicon monomers leads to the in situ formation of silica/polysiloxane particles and the surrounding polyamide 6 matrix in one step. Moreover, 3-aminopropyltriethoxysilane has been added to the three-component-system to achieve covalent bonding between organic and inorganic phases and to inhibit agglomeration of the silica particles. Chemical structures and morphologies of the composites have been investigated by solid-state NMR and FTIR spectroscopy as well as electron microscopy and SEC measurements. Structural effects on thermal properties have been studied by DSC and TGA measurements.

6.
RSC Adv ; 8(55): 31673-31681, 2018 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-35548201

RESUMO

Organic-inorganic hybrid materials with urethane functionalities were obtained by simultaneous twin polymerization of twin prepolymers in combination with the ideal twin monomer 2,2'-spirobi[4H-1,3,2-benzodioxasiline]. The twin prepolymers consist of a urethane-based prepolymer with reactive terminal groups which can react during the twin polymerization process. Nanostructured hybrid materials with integrated dialkylsiloxane crosslinked urethane structures, phenolic resin and SiO2 are obtained in a one pot process. The effects of the polymerization temperature as well as those of various catalysts and reagent ratios on the polymerization behavior were investigated. The molecular structures of the obtained materials were determined by 13C- and 29Si-{1H}-CP-MAS NMR spectroscopies. HAADF-STEM-measurements were performed to prove the distribution of silicon in the hybrid material.

9.
Euro Surveill ; 19(39)2014 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-25306981

RESUMO

On 15 August 2012, an increase in the number of Salmonella Thompson cases was noticed by the Salmonella surveillance in the Netherlands. A case­control study was performed, followed by a food investigation. In total 1,149 cases were laboratory-confirmed between August and December 2012 of which four elderly (76­91 years) were reported to have died due to the infection. The cause of the outbreak was smoked salmon processed at a single site. The smoked salmon had been continuously contaminated in the processing lines through reusable dishes, which turned out to be porous and had become loaded with bacteria. This is the largest outbreak of salmonellosis ever recorded in the Netherlands. The temporary closure of the processing site and recall of the smoked salmon stopped the outbreak. An estimated four to six million Dutch residents were possibly exposed to the contaminated smoked salmon and an estimated 23,000 persons would have had acute gastroenteritis with S. Thompson during this outbreak. This outbreak showed that close collaboration between diagnostic laboratories, regional public health services, the national institute for public health and the food safety authorities is essential in outbreak investigations.


Assuntos
Surtos de Doenças , Produtos Pesqueiros/microbiologia , Salmão/microbiologia , Intoxicação Alimentar por Salmonella/mortalidade , Infecções por Salmonella/mortalidade , Salmonella enterica/isolamento & purificação , Idoso , Idoso de 80 Anos ou mais , Animais , Estudos de Casos e Controles , Diarreia/epidemiologia , Produtos Pesqueiros/análise , Manipulação de Alimentos/métodos , Gastroenterite/epidemiologia , Humanos , Masculino , Países Baixos/epidemiologia , Vigilância da População , Intoxicação Alimentar por Salmonella/diagnóstico , Intoxicação Alimentar por Salmonella/microbiologia , Infecções por Salmonella/diagnóstico , Infecções por Salmonella/microbiologia , Salmonella enterica/classificação , Inquéritos e Questionários
11.
Haemophilia ; 17(6): 872-4, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21342368

RESUMO

Haemorrhagic manifestations in patients with haemophilia A and B are considered quite similar for comparable level of factor deficiency. We investigated the bleeding frequency and factor usage between HA and HB patients with comparable disease severities. We collected data on frequency of bleeds and factor concentrate utilization over 3 years, from January 2001 to December 2003. Information was gathered from home infusion logs recorded by patients or their parents, and treatment records from the Hemophilia Clinic or the Hospital Emergency Department. Data were available on 58 patients with severe HA (FVIII < 0.01 U mL(-1)), 10 with moderate HA (FVIII < 0.05 U mL(-1)), 15 with severe HB, and five with moderate HB who required treatment for episodic bleeds, postoperative haemostasis and for primary or secondary prophylaxis. The HA patients bled more frequently than HB patients (14.4 vs. 8.63 bleeds/patient/year), but used similar amounts of concentrate per year. HA patients underwent surgical procedures 3.2 times more frequently than HB patients to correct musculoskeletal complications. A total of 21,363,409 IU of recombinant FVIII was used by patients with HA (104,722 IU/patient/year) and 6,430, 960 IU of recombinant factor IX, by patients with HB (107,182 IU/patient/year). The difference in factor concentrate usage is not statistically significant (P > 0.05). The decrease in bleed frequency in haemophilia B indicates that the conclusions from randomized trials of prophylaxis in HA may not be accurately applied to HB.


Assuntos
Coagulantes/administração & dosagem , Fator IX/administração & dosagem , Fator VIII/administração & dosagem , Hemofilia A/complicações , Hemofilia A/tratamento farmacológico , Hemofilia B/complicações , Hemofilia B/tratamento farmacológico , Hemorragia/epidemiologia , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Humanos , Lactente , Pessoa de Meia-Idade , Proteínas Recombinantes/administração & dosagem , Estudos Retrospectivos , Adulto Jovem
13.
Klin Padiatr ; 222(3): 134-9, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20514615

RESUMO

BACKGROUND: Neonatal aortic thrombosis is a rare occurrence, but can be fatal. Treatment of this condition is hampered by the lack of large studies involving this pediatric population. Reporting of this condition is also not standardized. METHODS: The purpose of this review is to collate available literature on the incidence, risk factors, presentation, treatment and outcome of neonatal aortic thrombosis as well as suggest a treatment model. RESULTS: A Medline search of PubMed, OVID and Cochrane databases was undertaken using the key words "neonatal", "infant", "aorta", "aortic", "thrombosis", "thrombus" and "clot". Limits were set for articles that were English language only and published between 1980 and September 2009. Following review of all articles using predetermined search words and criteria, 38 were found with sufficient data for our purpose. The reported total number of neonatal patients with aortic thrombosis was 148 and 78% of the aortic thromboses in this review were related to arterial umbilical catheterization. CONCLUSIONS: We have suggested a classification system to standardize reporting of neonatal aortic thrombosis, as well as a treatment decision tree, and a clinical guide for the treatment of thrombosis in children. As always, clinicians should balance the risks and benefits of their decision to treat with the level of local expertise. This guide may specifically serve the neonatal population with line-related aortic thrombosis.


Assuntos
Doenças da Aorta/etiologia , Doenças do Prematuro/etiologia , Trombose/etiologia , Anticoagulantes/uso terapêutico , Doenças da Aorta/diagnóstico , Doenças da Aorta/epidemiologia , Doenças da Aorta/terapia , Aortografia , Cateteres de Demora/efeitos adversos , Estudos Transversais , Humanos , Recém-Nascido , Doenças do Prematuro/diagnóstico , Doenças do Prematuro/epidemiologia , Doenças do Prematuro/terapia , Sistema de Registros , Fatores de Risco , Terapia Trombolítica , Trombose/diagnóstico , Trombose/epidemiologia , Trombose/terapia , Resultado do Tratamento , Ultrassonografia , Artérias Umbilicais
14.
Protein Pept Lett ; 17(6): 723-31, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20015023

RESUMO

tate-of-the-art biochemistry methods in combination with an automated phenotyping method demonstrate the high potential of transgenic tobacco plants in producing properly-folded therapeutic proteins for the treatment of protein-misfolding diseases (e.g., Alzheimer's disease). This molecular farming approach led to highest protein production of hydroponically-grown tobacco compared to other growth substrates generally used in plant cultivation.


Assuntos
Doença de Alzheimer/prevenção & controle , Nicotiana/metabolismo , Proteínas de Plantas/metabolismo , Proteínas de Plantas/uso terapêutico , Biomassa , Biotecnologia/métodos , Hidroponia/métodos , Nitratos/metabolismo , Nitrogênio/metabolismo , Preparações Farmacêuticas/metabolismo , Fosfatos/metabolismo , Brotos de Planta/genética , Brotos de Planta/crescimento & desenvolvimento , Brotos de Planta/metabolismo , Plantas Geneticamente Modificadas , Compostos de Amônio Quaternário/metabolismo , Tecnologia Farmacêutica/métodos , Fatores de Tempo , Nicotiana/genética , Nicotiana/crescimento & desenvolvimento
15.
Hum Factors ; 38(2): 288-99, 1996 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8768490

RESUMO

Skilled performers in complex environments rely heavily on heuristic strategies to cope with the time pressure and complexity of dynamic tasks. We suggest that the use of task simplification strategies based largely on perception and pattern recognition is fundamental to the novice-expert shift in dynamic decision making. We therefore suggest that interface training interventions should support the development of highly effective and robust heuristic strategies, rather than the development of more abstract, cognitively intensive strategies. A pair of empirical studies are presented that investigated the benefits of training interventions aimed at supporting perceptual and pattern-recognitional activities in dynamic environments. Results suggest that the acquisition of skilled performance in dynamic environments can be accelerated by supporting perceptual activities in the service of dynamic decision making. Implications of these results for training, aiding, and interface design are discussed.


Assuntos
Sinais (Psicologia) , Tomada de Decisões , Capacitação em Serviço/métodos , Reconhecimento Automatizado de Padrão , Desempenho Psicomotor , Adulto , Análise de Variância , Feminino , Humanos , Masculino , Tempo de Reação
16.
17.
Artigo em Inglês | MEDLINE | ID: mdl-9962967
19.
Biochim Biophys Acta ; 1174(2): 153-61, 1993 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-8357832

RESUMO

The elongation factor G (EF-G) GTPase activity is induced by either 70S ribosomes or 50S ribosomal subunits. The GTPase activity induced by 50S ribosomal subunits is predominant at low concentrations of monovalent cations and decreases with increasing concentrations of K+ or NH4+. Double-logarithmic plots of the data reveal straight lines with different slopes for low and high concentrations of monovalent cations, respectively, intersecting at the same concentration of monovalent cations where maximal EF-G GTPase activity is measured in the presence of both ribosomal subunits. Substantially the same curves are obtained when 50S ribosomal subunits are substituted by 50S CsCl-core particles partially reconstituted by addition of purified 50S split proteins L7/L12. Intact 30S ribosomal subunits, but not 30S CsCl-core particles are able to associate with 50S ribosomal subunits and to modulate ribosome-dependent EF-G GTPase activity. Therefore, our data clearly show that the biphasic courses of the NH4+ and K+ curves of EF-G GTPase activity induced by 50S ribosomal subunits are not due to contaminations with 30S ribosomal subunits but result from different conformations of EF-G/50S ribosomal-subunit complexes at low and high concentrations of monovalent cations, respectively. CD spectra of 50S ribosomal subunits measured under different salt conditions have shown that the conformation of the 50S ribosomal subunits is strongly dependent on the concentration of monovalent cations. The conformation of 30S ribosomal subunits is, however, considerably stronger influenced by the Mg2+ than by the concentration of monovalent cations. The salt effects on the conformation of the 30S ribosomal subunits correspond to the salt effects on the association of ribosomal subunits and the modulation of EF-G GTPase activity by 30S ribosomal subunits. Since, in the presence of both ribosomal subunits, EF-G GTPase activity is maximal at the same concentration of monovalent cations where obviously a spontaneous conformation change of 50S ribosomal subunits takes place, we postulate that EF-G GTPase primarily acts on the ribosomes by changing the conformation of 50S ribosomal subunits. The resulting model is based on the assumption that EF-G GTPase activity is considerably more strongly induced by the 'substrate conformation' ('state I') than by the 'product conformation' of the 50S ribosomal subunits ('state II'). A spontaneous transformation of 'state II' to 'state I' is expected to occur in the absence of mRNA, aminoacyl-tRNA and EF-T especially under salt conditions favouring state I.


Assuntos
Fatores de Elongação Ligados a GTP Fosfo-Hidrolases/metabolismo , Fatores de Alongamento de Peptídeos/metabolismo , RNA Ribossômico/química , Ribossomos/metabolismo , Cátions , Dicroísmo Circular , Escherichia coli/metabolismo , Guanosina Trifosfato/metabolismo , Conformação de Ácido Nucleico , Fator G para Elongação de Peptídeos
20.
Pharmacotherapy ; 13(3): 177-88, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8321732

RESUMO

Oligonucleotide pharmacotherapy, although in a very preliminary stage, promises to provide new, highly specific tools for the treatment of human diseases, such as viral illnesses and cancer. The agents have several proposed mechanisms of action, including inhibition of translation, splicing, and transcription. In addition, the bioefficacy of oligonucleotides may be enhanced by phosphorothioates, methylphosphonates, and alpha-oligonucleotides. The agents are delivered by the ex vivo or topical route, and new methods of administration are under study. It is predicted that within the decade these agents will be used routinely to treat several serious illnesses.


Assuntos
Oligonucleotídeos , Sistemas de Liberação de Medicamentos , Desenho de Fármacos , Humanos , Neoplasias/tratamento farmacológico , Oligonucleotídeos/química , Oligonucleotídeos/genética , Oligonucleotídeos/uso terapêutico , Oligonucleotídeos Antissenso/farmacologia , Oligonucleotídeos Antissenso/uso terapêutico , Biossíntese de Proteínas/genética , Splicing de RNA/genética , Transcrição Gênica/genética , Viroses/tratamento farmacológico
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