Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 593
Filtrar
Mais filtros

Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
Persoonia ; 49: 136-170, 2022 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-38234382

RESUMO

Nolanea is a well-known and long-established subgenus of the genus Entoloma traditionally defined mainly by the mycenoid basidiocarps of the included species. Until now, revisions of this subgenus including molecular data exist only on a regional scale. In this study, the phylogeny of species of Nolanea is analysed based on multi-gene DNA sequences including data of specimens from all continents. New primers are designed for the mitochondrial small subunit and RPB2. The performance of the DNA loci in reconstructing the phylogeny in subg. Nolanea is evaluated. An ancestral state reconstruction is used to infer the character state evolution as well as the importance and reliability of morphological characters used to define subclades below subgeneric rank. Based on the results, seven sections are recognised in Nolanea: the sections Holoconiota, Infularia, Mammosa, Nolanea, Papillata, Staurospora, and the newly described sect. Elegantissima. A large phylogeny based on the fungal barcode rDNA ITS with numerous type sequences is used to evaluate current species concepts. Several names are revealed to be synonyms of older names. Four species new to science are described, namely E. altaicum, E. argillaceum, E. cornicolor, and E. incognitum. Lectotypes, epitypes or neotypes are designated for E. cetratum, E. clandestinum, E. conferendum, E. cuspidiferum, E. hebes, E. minutum, E. nitens, and E. rhodocylix. The re-evaluation of the limits of subg. Nolanea leads to an altered concept excluding species with distinct, lageniform cheilocystidia. The section Ameides is placed in subg. Leptonia. For several species formerly accommodated in Nolanea, but excluded now, viz., E. lepiotoides, E. rhombisporum, E. subelegans, and E. velenovskyi the taxonomic position remains unclear, because of the yet unresolved phylogeny of the whole genus Entoloma. Citation: Reschke K, Morozova OV, Dima B, et al. 2022. Phylogeny, taxonomy, and character evolution in Entoloma subgenus Nolanea. Persoonia 49: 136-170. https://doi.org/10.3767/persoonia.2022.49.04.

2.
Persoonia ; 47: 1-44, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37693797

RESUMO

The Lactifluus clarkeae complex is a commonly observed, generally brightly coloured, group of mushrooms that are usually associated with Nothofagus or Myrtaceous hosts in Australia and New Zealand. For this study collections labelled as 'Lactarius clarkeae', 'Russula flocktoniae' and 'Lactarius subclarkeae' were examined morphologically and molecularly. Analyses of molecular data showed a high cryptic diversity, with sequences scattered across 11 clades in three subgenera within Lactifluus, and a single collection in Russula. We select epitypes to anchor the currently accepted concepts of Lf. clarkeae s.str. and Lf. flocktoniae s.str. The name Lf. subclarkeae could not be applied to any of the collections examined, as none had a lamprotrichoderm pileipellis. Lactifluus clarkeae var. aurantioruber is raised to species level, and six new species are described, three in subg. Lactifluus: Lf. jetiae, Lf. pagodicystidiatus, and Lf. rugulostipitatus, and three in subg. Gymnocarpi: Lf. albens, Lf. psammophilus, and Lf. pseudoflocktoniae. A new collection of Lf. russulisporus provides a significant range extension for the species. Untangling this complex will enable better identification of species and increase understanding of diversity and specific habitat associations of macrofungi. Citation: Lebel T, Douch J, Tegart L, et al. 2021. Untangling the Lactifluus clarkeae - Lf. flocktoniae (Russulaceae) species complex in Australasia. Persoonia 47: 1-44. https://doi.org/10.3767/persoonia.2021.47.01.

3.
Persoonia ; 47: 1-44, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38352975

RESUMO

The Lactifluus clarkeae complex is a commonly observed, generally brightly coloured, group of mushrooms that are usually associated with Nothofagus or Myrtaceous hosts in Australia and New Zealand. For this study collections labelled as 'Lactarius clarkeae', 'Russula flocktoniae' and 'Lactarius subclarkeae' were examined morphologically and molecularly. Analyses of molecular data showed a high cryptic diversity, with sequences scattered across 11 clades in three subgenera within Lactifluus, and a single collection in Russula. We select epitypes to anchor the currently accepted concepts of Lf. clarkeae s.str. and Lf. flocktoniae s.str. The name Lf. subclarkeae could not be applied to any of the collections examined, as none had a lamprotrichoderm pileipellis. Lactifluus clarkeae var. aurantioruber is raised to species level, and six new species are described, three in subg. Lactifluus: Lf. jetiae, Lf. pagodicystidiatus, and Lf. rugulostipitatus, and three in subg. Gymnocarpi: Lf. albens, Lf. psammophilus, and Lf. pseudoflocktoniae. A new collection of Lf. russulisporus provides a significant range extension for the species. Untangling this complex will enable better identification of species and increase understanding of diversity and specific habitat associations of macrofungi. Citation: Lebel T, Douch J, Tegart L, et al. 2021. Untangling the Lactifluus clarkeae - Lf. flocktoniae (Russulaceae) species complex in Australasia. Persoonia 47: 1-44. https://doi.org/10.3767/persoonia.2021.47.01.

4.
Mol Genet Metab ; 130(1): 77-86, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32178982

RESUMO

In recent years the oxysterol species cholestane-3ß, 5α, 6ß-triol (C-triol) has found application as a diagnostic biomarker for Niemann-Pick disease type C. Other studies have described increased C-triol in patients with Niemann-Pick disease type A/B and milder increases in lysosomal acid lipase deficiency (LALD), whereas they note normal C-triol levels in Smith-Lemli-Opitz syndrome (SLOS) and familial hypercholesterolaemia (FH) patients. Herein, we review data collected in our laboratory during method evaluation along with 5 years of routine analysis and present findings which differ from those reported by other groups with respect to LALD, SLOS and FH in particular, whilst providing further evidence regarding the clinical sensitivity and specificity of this biomarker, which are difficult to accurately assess. All of our Wolman disease (severe LALD) patients have demonstrated gross elevations of C-triol at diagnosis, with reduction to normal levels after induction of enzyme replacement therapy. In diagnostic specimens from SLOS patients we observed very low or undetectable C-triol levels whereas in post-therapeutic SLOS patients demonstrated normalised levels; we also describe a homozygous FH patient in which C-triol is significantly elevated. Upon investigation, we found that C-triol was formed artefactually from cholesterol during our sample preparation, i.e. this is a false positive of analytical origin; at present it is unclear whether similar effects occur during sample preparation in other laboratories. Our data demonstrates clinical sensitivity of 100% during routine application to diagnostic specimens; this is in keeping with other estimates, yet in a small proportion of patients diagnosed prior to C-triol measurement, either by Filipin staining of fibroblasts or molecular genetics, we have observed normal C-triol concentrations. Clinical specificity of C-triol alone is 93.4% and 95.3% when performed in conjunction with lysosomal enzymology. These performance statistics are very similar to those achieved with Filipin staining of cultured fibroblasts in the 5 years preceding introduction of C-triol to routine use in our laboratory. It is increasingly apparent to us that although this analyte is a very useful addition to the diagnostic tools available for NPC, with considerable advantages over more invasive and time-consuming methods, the interpretation of results is complex and should be undertaken only in light of clinical details and results of other analyses including enzymology for lysosomal acid lipase and acid sphingomyelinase.


Assuntos
Colestanóis/sangue , Doença de Niemann-Pick Tipo C/diagnóstico , Doença de Wolman/diagnóstico , Adolescente , Adulto , Idoso , Biomarcadores/sangue , Criança , Pré-Escolar , Colestanóis/química , Colesterol/sangue , Cromatografia Líquida , Terapia de Reposição de Enzimas , Fibroblastos/metabolismo , Homozigoto , Humanos , Hiperlipoproteinemia Tipo II/sangue , Lactente , Recém-Nascido , Limite de Detecção , Pessoa de Meia-Idade , Doença de Niemann-Pick Tipo C/sangue , Oxisteróis/sangue , Sensibilidade e Especificidade , Espectrometria de Massas em Tandem , Doença de Wolman/sangue , Doença de Wolman
5.
Persoonia ; 42: 261-290, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31551621

RESUMO

A section-based taxonomy of Cortinarius, covering large parts of the temperate North and South Hemispheres, is presented. Thirty-seven previously described sections are reviewed, while another forty-two sections are proposed as new or as new combinations. Twenty additional clades are recovered but not formally described. Furthermore, six new or combined species names are introduced, and one species is neotypified. The structure is supported by morphological characters and molecular evidence, based on two (nrITS and nrLSU) and four (nrITS, nrLSU, rpb1 and rpb2) loci datasets and analysed by Maximum Likelihood methods (PhyML, RAxML). Altogether 789 Cortinarius samples were included in the study.

6.
Colorectal Dis ; 18(7): 650-3, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27135192

RESUMO

Worldwide, the guaiac faecal occult blood test (gFOBT) is being replaced with the more accurate faecal immunochemical test (FIT) for colorectal cancer (CRC) screening. From January 2016, the National Screening Committee in the UK has recommended a change from the gFOBT to the FIT following a successful Bowel Cancer Screening Programme pilot study with over 40 000 participants. Although the test has shown improved uptake and the ability to detect significantly more colorectal cancers and advanced adenomas, the higher uptake and test positivity will challenge the capacity of colonoscopy services. One of the main advantages of the FIT is that it provides a quantitative haemoglobin concentration which has been shown to relate to the risk of CRC. Risk scoring systems which combine the FIT concentration with risk factor assessment have been shown to improve the sensitivity of the test. This individualized approach to screening could enable those at greatest risk to be referred for colonoscopy, optimizing resource use and ultimately patient outcomes.


Assuntos
Neoplasias Colorretais/diagnóstico , Detecção Precoce de Câncer/tendências , Fezes/química , Previsões , Programas de Rastreamento/tendências , Detecção Precoce de Câncer/métodos , Guaiaco , Humanos , Programas de Rastreamento/métodos , Sangue Oculto , Valor Preditivo dos Testes
7.
Int J Colorectal Dis ; 27(11): 1485-91, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22842663

RESUMO

BACKGROUND AND AIMS: Aerobic exercise capacity appears impaired in children with inflammatory bowel disease (IBD). Whether this holds true in adults with IBD is not known. Using cardiopulmonary exercise testing (CPET), we assessed anaerobic threshold (AT) in such patients comparing data with reference values and other elective surgical patients. We also sought to confirm whether the presence of a fistula further reduced AT. METHODS: CPET was performed between November 2007 and December 2010 on patients awaiting abdominopelvic surgery. Gender-specific normal reference values were used for comparison. Unadjusted comparison between two groups was made using Mann-Whitney U test and by unpaired t test. Data were adjusted by analysis of covariance, using age and sex as covariates. Differences between patients' observed values and reference values were tested using paired t tests. RESULTS: Four hundred and fourteen patients (234 male) were studied (mean ± SD age, 56.6 ± 16.4 years; weight, 74.2 ± 15.6 kg). Adjusted AT values in Crohn's disease (CD) were lower than colorectal cancer (11.4 ± 3.4 vs 13.2 ± 3.5 ml.kg(-1).min(-1), p = 0.03) and for all other colorectal disease groups combined (12.6 ± 3.5 ml.kg(-1).min(-1), p = 0.03). AT of Ulcerative colitis (UC) and CD patients together were reduced compared to population reference values (p < 0.05). CONCLUSION: After adjusting for age and sex, CD patients had a reduced AT compared to patients with colorectal cancer and other colorectal disease groups combined. The pathogenesis of this low AT remains to be defined and warrants further investigation.


Assuntos
Teste de Esforço , Tolerância ao Exercício/fisiologia , Doenças Inflamatórias Intestinais/fisiopatologia , Doenças Inflamatórias Intestinais/cirurgia , Cuidados Pré-Operatórios , Adulto , Limiar Anaeróbio/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
8.
Nutr Metab Cardiovasc Dis ; 22(12): 1024-30, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21917432

RESUMO

BACKGROUND AND AIMS: A recent genome-wide association study identified rs2943641C > T, 500 kb from the insulin receptor substrate-1 gene (IRS1), as a type-2 diabetes (T2D) susceptibility locus. We aimed to replicate this association by meta-analysis and examine whether common variants within IRS1, present on the HumanCVD BeadChip, were associated with T2D risk. METHODS AND RESULTS: We genotyped rs2943641 in 2389 prevalent or incident T2D patients and 6494 controls from two prospective and three case studies based in UK and in the European Atherosclerosis Research Study-II (EARSII; n = 714). Thirty-three IRS1 variants had been genotyped in the prospective Whitehall-II study (n = 4752) using the HumanCVD BeadChip. In a fixed-effects meta-analysis of the UK study cohorts rs2943641T allele was associated with 6% lower risk of T2D (p = 0.18), with T-allele carriers having an odds ratio (OR) of 0.89 (95% confidence interval [CI]: 0.80-1.00, p = 0.056) compared to CC subjects. The T-allele was also associated with lower fasting insulin and homeostasis model assessment index of insulin resistance in Whitehall-II and with lower post-load insulin after an oral glucose tolerance test in EARSII (all p < 0.05). None of the IRS1 variants on the chip showed linkage disequilibrium with rs2943641. In silico analysis with follow-up genotyping (total n = 9313) identified that the rare allele of the IRS1 promoter variant rs6725556A > G showed association with reduced T2D risk (OR per G-allele: 0.82, 95%CI: 0.69-0.96, p = 0.015). CONCLUSIONS: We confirm the association of rs2943641T with T2D protection. There is a possible independent effect on risk of a putative IRS1 promoter variant.


Assuntos
Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Estudo de Associação Genômica Ampla/métodos , Proteínas Substratos do Receptor de Insulina/genética , Polimorfismo de Nucleotídeo Único , Alelos , Estudos de Casos e Controles , Simulação por Computador , Europa (Continente) , Predisposição Genética para Doença , Genótipo , Teste de Tolerância a Glucose , Homeostase , Humanos , Proteínas Substratos do Receptor de Insulina/metabolismo , Resistência à Insulina/genética , Desequilíbrio de Ligação , Modelos Logísticos , Análise Multivariada , Razão de Chances , Prevalência , Regiões Promotoras Genéticas , Fatores de Risco , População Branca/genética
9.
Nutr Metab Cardiovasc Dis ; 22(5): 417-25, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-21185702

RESUMO

Glutathione peroxidase-1 (GPx-1) is an endogenous anti-oxidant enzyme. The T allele of the GPx-1 rs1050450 (C > T) gene variant is associated with reduced enzyme activity. Our aim was to examine the association between this gene variant and peripheral neuropathy in two cross-sectional samples of subjects with diabetes: (i) 773 Caucasian subjects were genotyped from the UCL Diabetes and Cardiovascular disease Study (UDACS) and (ii) 382 Caucasian subjects from the Ealing Diabetes Study (EDS). Peripheral neuropathy status (and oxidised-LDL [Ox-LDL:LDL] and plasma Total Ant-ioxidant Status [TAOS] in UDACS), were analysed in relation to genotype. We observed that: (i) In UDACS, the odds ratio (OR) for peripheral neuropathy in the T allele carriers compared to the CC genotype was 1.61 [1.10-2.28], p = 0.01. This remained significant after adjustment for other risk factors. Ox-LDL:LDL ratio was significantly elevated in T allele carriers (CC vs. CT/TT: 16.3 ± 2.4 v 18.0 ± 2.9 U/mmol LDL, p = 0.02). (ii) In EDS, the OR for peripheral neuropathy in the T allele carriers compared to the CC genotype was 1.95 [1.11-3.42], p = 0.02. This remained significant after adjustment for other risk factors. In conclusion, we observed a significant association between the T allele and peripheral neuropathy and LDL oxidation. This is the first paper to examine the rs1050450 variant in two samples of Caucasian subjects with diabetes. Prospective analysis of the gene variant is required in diabetic and healthy cohorts with measured plasma markers of oxidative stress to investigate the described association further.


Assuntos
Neuropatias Diabéticas/genética , Glutationa Peroxidase/genética , Polimorfismo de Nucleotídeo Único , Idoso , Alelos , Antioxidantes/análise , Biomarcadores/sangue , Estudos de Casos e Controles , Estudos Transversais , Neuropatias Diabéticas/sangue , Neuropatias Diabéticas/etnologia , Neuropatias Diabéticas/metabolismo , Feminino , Frequência do Gene , Estudos de Associação Genética , Glutationa Peroxidase/metabolismo , Humanos , Lipoproteínas LDL/sangue , Londres , Masculino , Pessoa de Meia-Idade , Estresse Oxidativo , População Branca , Glutationa Peroxidase GPX1
10.
Eur J Appl Physiol ; 112(11): 3775-85, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22382668

RESUMO

Aerobic exercise increases 24-h fat oxidation following initiation of a high-fat diet. The objective of this study is to examine the time course of increased fat oxidation under exercise and sedentary conditions. Eighteen healthy subjects completed a randomized crossover design (sedentary and exercise visits) staying for five consecutive days in a metabolic chamber each visit. On day 1, 30% of energy intake was from fat; days 2-5 had 50% of energy as fat. During exercise, subjects rode on a stationary cycle at 45% of VO2max for 1 h in the mornings and evenings. Respiratory gases and urinary nitrogen were collected to calculate macronutrient oxidation and non-protein respiratory exchange ratio (NPRER). This data, collected continuously (24-h periods), were subsequently divided into three time segments: (1) exercise + recovery (1000-1200 hours, 2100-2200 hours), (2) sleep (2300-0645 hours), and (3) wake (all remaining hours). NPRER on exercise versus sedentary visits was lower for the sleep segment (0.77 ± 0.01 01 vs. 0.81 ± 0.01, p < 0.001), higher for the exercise + recovery segment (0.88 ± 0.01 vs. 0.86 ± 0.01, p < 0.001), and was not different for the wake segment. Fat oxidation was significantly higher for exercise versus sedentary treatments during sleep (41 ± 2 vs. 31 ± 2 g), wake (62 ± 3 vs. 51 ± 3 g), and exercise + recovery segments (33 ± 3 vs.16 ± 1 g), but so was fat intake by design (171 ± 8 vs. 128 ± 7 g/d). Although exercise showed greater fat oxidation during all segments, dietary fat intake was also higher. Therefore, based on NPRER, the time of day during which the exercise treatment increased the ratio of fat to carbohydrate oxidation was during sleep.


Assuntos
Ritmo Circadiano/fisiologia , Dieta Hiperlipídica , Ingestão de Energia/fisiologia , Exercício Físico/fisiologia , Tecido Adiposo , Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Oxirredução , Consumo de Oxigênio
11.
Diabetologia ; 54(7): 1710-9, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21455730

RESUMO

AIMS/HYPOTHESIS: We quantified the effect of ADRA2A (encoding α-2 adrenergic receptor) variants on metabolic traits and type 2 diabetes risk, as reported in four studies. METHODS: Genotype data for ADRA2A single nucleotide polymorphisms (SNPs) rs553668 and rs10885122 were analysed in >17,000 individuals (1,307 type 2 diabetes cases) with regard to metabolic traits and type 2 diabetes risk. Two studies (n = 9,437), genotyped using the Human Cardiovascular Disease BeadChip, provided 12 additional ADRA2A SNPs. RESULTS: Rs553668 was associated with per allele effects on fasting glucose (0.03 mmol/l, p = 0.016) and type 2 diabetes risk (OR 1.17, 95% CI 1.04-1.31; p = 0.01). No significant association was observed with rs10885122. Of the 12 SNPs, several showed associations with metabolic traits. Overall, after variable selection, rs553668 was associated with type 2 diabetes risk (OR 1.38, 95% CI 1.09-1.73; p = 0.007). rs553668 (per allele difference 0.036 mmol/l, 95% CI 0.008-0.065) and rs17186196 (per allele difference 0.066 mmol/l, 95% CI 0.017-0.115) were independently associated with fasting glucose, and rs17186196 with fasting insulin and HOMA of insulin resistance (4.3%, 95% CI 0.6-8.1 and 4.9%, 95% CI 1.0-9.0, respectively, per allele). Per-allele effects of rs491589 on systolic and diastolic blood pressure were 1.19 mmHg (95% CI 0.43-1.95) and 0.61 mmHg (95% CI 0.11-1.10), respectively, and those of rs36022820 on BMI 0.58 kg/m(2) (95% CI 0.15-1.02). CONCLUSIONS/INTERPRETATION: Multiple ADRA2A SNPs are associated with metabolic traits, blood pressure and type 2 diabetes risk. The α-2 adrenergic receptor should be revisited as a therapeutic target for reduction of the adverse consequences of metabolic trait disorders and type 2 diabetes.


Assuntos
Glicemia/metabolismo , Pressão Sanguínea/fisiologia , Índice de Massa Corporal , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/genética , Jejum/sangue , Receptores Adrenérgicos alfa 2/genética , Idoso , Feminino , Predisposição Genética para Doença/genética , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único/genética , Estudos Prospectivos
12.
Curr Opin Cell Biol ; 2(2): 285-95, 1990 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2114126

RESUMO

The study of oncogenes offers insights into many steps in signal transduction. Rapid progress is possible because of the combination of biochemistry and genetics--unique in vertebrate cell biology--the availability of specific clones and antibodies, sequence information, dominant mutants, and biochemical assays of function. The wealth of detail on oncogenes and proto-oncogenes continues to increase dramatically. Hopefully, in the next year or two some of the gaps will be filled in and all the steps along at least one pathway from the cell membrane to the nucleus will be understood.


Assuntos
Transformação Celular Neoplásica/genética , Oncogenes/fisiologia , Animais , Núcleo Celular/metabolismo , Proteínas de Ligação ao GTP/fisiologia , Proteínas Ativadoras de GTPase , Humanos , Meiose/fisiologia , Proteínas de Neoplasias/fisiologia , Proteína Oncogênica p21(ras)/fisiologia , Proteínas Tirosina Quinases/fisiologia , Proteínas/fisiologia , Transdução de Sinais/fisiologia , Proteínas Ativadoras de ras GTPase
13.
Curr Opin Cell Biol ; 7(6): 798-805, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8608010

RESUMO

Evolutionarily conserved from yeast to man, mitogen-activated protein kinase (MAPK) pathways respond to a variety of disparate signals which induce differentiation, proliferation, or changes in intracellular enzyme regulation. Recent advances have identified two new mammalian MAPK relatives, JNK1 and p38, and the pathways which are responsible for their activation.


Assuntos
Proteínas Quinases Dependentes de Cálcio-Calmodulina/metabolismo , Proteínas de Choque Térmico/metabolismo , Mitógenos/farmacologia , Monoéster Fosfórico Hidrolases/metabolismo , Leveduras/metabolismo , Animais , Proteínas Quinases Dependentes de Cálcio-Calmodulina/efeitos dos fármacos , Proteínas de Choque Térmico/efeitos dos fármacos , Mamíferos , Leveduras/citologia , Leveduras/efeitos dos fármacos
14.
Curr Opin Cell Biol ; 12(1): 97-103, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10679358

RESUMO

The most important discovery in the field is that the Arp2/3 complex nucleates assembly of actin filaments with free barbed ends. Arp2/3 also binds the sides of actin filaments to create a branched network. Arp2/3's nucleation activity is stimulated by WASP family proteins, some of which mediate signaling from small G-proteins. Listeria movement caused by actin polymerization can be reconstituted in vitro using purified proteins: Arp2/3 complex, capping protein, actin depolymerizing factor/cofilin, and actin. actin depolymerizing factor/cofilin increases the rate at which actin subunits leave pointed ends, and capping protein caps barbed ends.


Assuntos
Citoesqueleto de Actina/metabolismo , Actinas/metabolismo , Proteínas do Citoesqueleto , Citoesqueleto de Actina/química , Fatores de Despolimerização de Actina , Proteína 2 Relacionada a Actina , Proteína 3 Relacionada a Actina , Animais , Proteína de Capeamento de Actina CapZ , Proteínas de Transporte/metabolismo , Movimento Celular , Gelsolina/metabolismo , Humanos , Proteínas dos Microfilamentos/metabolismo , Proteínas Motores Moleculares/metabolismo , Proteínas Musculares/metabolismo , Tropomodulina
15.
Nutr Metab Cardiovasc Dis ; 21(7): 476-84, 2011 07.
Artigo em Inglês | MEDLINE | ID: mdl-20227263

RESUMO

BACKGROUND AND AIMS: IL-18 expression is up-regulated in atherosclerotic plaques, and higher levels are seen in obese and Type 2 Diabetic individuals. More recently, a possible role for IL-18 in glucose and energy homeostasis has been suggested. METHODS AND RESULTS: We investigated variation within the IL18 gene and its association with measures of obesity and the metabolic syndrome. Five IL18 tagging single nucleotide polymorphisms (rs1946519, rs2043055, rs549908, rs360729, rs3882891) were selected and genotyped in the Gene-Diet Attica Investigation on childhood obesity (GENDAI) (age range 10-14 yrs); in young European men in the second European Atherosclerosis Research offspring Study (EARSII), an offspring study (age range 18-28 yrs) and in a group of healthy women from the Greek Obese Women study (GrOW) (age range 18-74 yrs). Six common haplotypes were observed. In GrOW, Hap6 (Frequency-2.6%) was associated with higher insulin levels (p<0.0001), estimates of HOMA(-Insulin Resistance) (p<0.0001) and HOMA(-ß-cell) (p<0.0001) compared to the common haplotype Hap1 (Frequency-33.2%). In EARSII, rs2043055 was associated with peak and area under the curve triglycerides (p=0.001 and p=0.002, respectively) after an oral fat tolerance test in 'cases' but not 'controls'. None of the haplotypes were associated with measures of body fatness in any of the studies. CONCLUSION: Association of IL18 variation with insulin levels and estimates of insulin resistance were only observed in our adult study, suggesting that the effects of IL-18 are only associated with increasing age. Taken together with the association of IL18 variants with post-prandial measures, this provides support for IL-18 as a metabolic factor.


Assuntos
Resistência à Insulina/genética , Insulina/sangue , Interleucina-18/genética , Síndrome Metabólica/genética , Obesidade/genética , Polimorfismo de Nucleotídeo Único , Adolescente , Adulto , Idoso , Criança , Europa (Continente) , Feminino , Frequência do Gene , Estudos de Associação Genética , Predisposição Genética para Doença , Grécia , Humanos , Masculino , Síndrome Metabólica/sangue , Pessoa de Meia-Idade , Obesidade/sangue , Período Pós-Prandial , Triglicerídeos/sangue , Adulto Jovem
16.
Vet Pathol ; 48(5): 948-63, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21078883

RESUMO

Tissues from sequential-kill time course studies of bovine spongiform encephalopathy (BSE) were examined to define PrP immunohistochemical labeling forms and map disease-specific labeling over the disease course after oral exposure to the BSE agent at two dose levels. Study was confined to brainstem, spinal cord, and certain peripheral nervous system ganglia-tissues implicated in pathogenesis and diagnosis or disease control strategies. Disease-specific labeling in the brainstem in 39 of 220 test animals showed the forms and patterns observed in natural disease and invariably preceded spongiform changes. A precise temporal pattern of increase in labeling was not apparent, but labeling was generally most widespread in clinical cases, and it always involved neuroanatomic locations in the medulla oblongata. In two cases, sparse labeling was confined to one or more neuroanatomic nuclei of the medulla oblongata. When involved, the spinal cord was affected at all levels, providing no indication of temporal spread within the cord axis or relative to the brainstem. Where minimal PrP labeling occurred in the thoracic spinal cord, it was consistent with initial involvement of general visceral efferent neurons. Labeling of ganglia involved only sensory ganglia and only when PrP was present in the brainstem and spinal cord. These experimental transmissions mimicked the neuropathologic findings in BSE-C field cases, independent of dose of agent or stage of disease. The model supports current diagnostic sampling approaches and control measures for the removal and destruction of nervous system tissues in slaughtered cattle.


Assuntos
Tronco Encefálico/patologia , Encefalopatia Espongiforme Bovina/patologia , Proteínas PrPSc/análise , Medula Espinal/patologia , Zoonoses/etiologia , Animais , Bovinos , Progressão da Doença , Encefalopatia Espongiforme Bovina/diagnóstico , Imuno-Histoquímica/métodos , Imuno-Histoquímica/veterinária , Estudos Retrospectivos
17.
Appetite ; 56(1): 171-8, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21035513

RESUMO

To compare the effects of both dietary fatty acid composition and exercise vs. sedentary conditions on circulating levels of hunger and satiety hormones. Eight healthy males were randomized in a 2 × 2 crossover design. The four treatments were 3 days of HF diets (50% of energy) containing high saturated fat (22% of energy) with exercise (SE) or sedentary (SS) conditions, and high monounsaturated fat (30% of energy) with exercise (UE) or sedentary (US) conditions. Cycling exercise was completed at 45% of VO(2)max for 2h daily. On the third HF day, 20 blood samples were drawn over a 24h period for each hormone (leptin, insulin, ghrelin, and peptide YY (PYY)). A visual analog scale (VAS) was completed hourly between 0800 and 2200. Average 24h leptin and insulin levels were lower while 24h PYY was higher during exercise vs. sedentary conditions. FA composition did not differentially affect 24h hormone values. VAS scores for hunger and fullness did not differ between any treatment but did correlate with ghrelin, leptin, and insulin. High saturated or unsaturated fat diets did not differ with respect to markers of hunger or satiety. Exercise decreased 24h leptin and insulin while increasing PYY regardless of FA composition.


Assuntos
Gorduras na Dieta/administração & dosagem , Exercício Físico/fisiologia , Ácidos Graxos/farmacologia , Fome/efeitos dos fármacos , Hormônios Peptídicos/sangue , Saciação/efeitos dos fármacos , Comportamento Sedentário , Adolescente , Adulto , Ciclismo/fisiologia , Biomarcadores/sangue , Humanos , Insulina/sangue , Leptina/sangue , Masculino , Peptídeo YY/sangue , Método Simples-Cego , Adulto Jovem
18.
Fungal Syst Evol ; 8: 9-25, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35005569

RESUMO

Three Australian species with sequestrate basidiome forms are recorded for the first time in the genus Lactifluus based on nuclear ITS-LSU and morphological data. These species represent three rare independent evolutionary events resulting in sequestrate basidiomes arising from agaricoid species in three different sections in two subgenera. All three species have highly reduced basidiome forms, and no species with intermediate forms have been found. Lactifluus dendriticus is unique in the genus in having highly branched, dendritic terminal elements in the pileipellis. We provide full descriptions of two species: Zelleromyces dendriticus (= Lactifluus dendriticus comb. nov.) in Lactifluus subg. Lactifluus sect. Gerardii, and Lactifluus geoprofluens sp. nov. in Lf. subg. Lactifluus sect. Lactifluus. A reduced description is provided for the third, Lactifluus sp. prov. KV181 in Lf. subg. Pseudogymnocarpi sect. Pseudogymnocarpi, as it is currently known from a single sequence.

19.
Oper Res Health Care ; 30: 100311, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36466119

RESUMO

During the first wave of the COVID-19 pandemic it emerged that the nature and magnitude of demand for mental health services was changing. Considerable increases were expected to follow initial lulls as treatment was sought for new and existing conditions following relaxation of 'lockdown' measures. For this to be managed by the various services that constitute a mental health system, it would be necessary to complement such projections with assessments of capacity, in order to understand the propagation of demand and the value of any consequent mitigations. This paper provides an account of exploratory modelling undertaken within a major UK healthcare system during the first wave of the pandemic, when actionable insights were in short supply and decisions were made under much uncertainty. In understanding the impact on post-lockdown operational performance, the objective was to evaluate the efficacy of two considered interventions against a baseline 'do nothing' scenario. In doing so, a versatile and purpose-built discrete time simulation model was developed, calibrated and used by a multi-disciplinary project working group. The solution, representing a multi-node, multi-server queueing network with reneging, is implemented in open-source software and is freely and publicly available.

20.
Sci Total Environ ; 768: 144987, 2021 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-33736349

RESUMO

Human occupation of and alteration of the world's coast has transformed large stretches of it into Coupled Human-Natural Systems (CHANS) in which humans both influence and are influenced by coastal evolution. In such systems, human activity is as critical on natural resilience as processes and sediment supply derived from the natural setting. Pre- and post-storm observations of these interactions on the intensively developed Atlantic coast of the Gulf of Cádiz, (Spain and Portugal) are examined to determine natural and engineering resilience. Three case studies are used in three CHANS, showing that human interventions interact in complex ways with the natural system influencing post-storm recovery. In natural coasts, storm impact is assessed in terms of geomorphological response; on developed coasts, it is quantified as damage to infrastructure or loss of amenity. Preparedness, availability of resources, choice of response and the speed at which human agencies respond affect resilience for post-storm beach behaviour. Results show in some sites natural resilience adjusting by post-storm sediment transfers and an equilibrium morphology that may differ from pre-storm morphology; engineering resilience ensured that CHANS regained their pre-storm human infrastructure and amenity. Their management requires a fundamentally different approach to that of natural coastlines. The current immature stage of understanding of CHANS (especially the human preparedness and response components) is illustrated by the case studies presented where short-term political decisions and reactions to storms play a strong role in post-storm response. The nature and extent of many developed coasts as CHANS is slowly becoming more widely acknowledged, but to increase natural resilience and decrease vulnerability in CHANS better planning is required so that future storms are anticipated and when they happen, pre-planned human response actions are activated. Storms are an integral and inevitable element in the behaviour of coastal CHANS, not a disaster or emergency.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA