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2.
Infect Dis Now ; 54(3): 104888, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38494118

RESUMO

OBJECTIVES: Immunocompromised B-cell-depleted patients are at risk of developing protracted COVID-19, a clinical syndrome characterized by prolonged viral shedding and respiratory symptoms that can lead to hypoxemic pneumonia. Our aim is to describe this unusual condition and its treatment. PATIENTS AND METHODS: This monocentric retrospective study reports six cases of severe organizing pneumonia that developed during the clinical course of protracted COVID-19. RESULTS: All patients developed organizing pneumonia (OP) in the setting of protracted COVID. Clinical improvement was obtained after several treatment lines including specific antiviral agents and occurred simultaneously with control of the viral load. CONCLUSION: As it was the most frequent presentation of protracted COVID-19 in our survey, we believe that this specific form of organizing pneumonia warrants increased awareness. Furthermore, specific antiviral therapy seems to control this condition.


Assuntos
COVID-19 , Pneumonia em Organização , Pneumonia , Humanos , COVID-19/complicações , Estudos Retrospectivos
3.
J Med Genet ; 45(2): 93-9, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17893117

RESUMO

BACKGROUND: Immunodeficiency, centromeric instability and facial dysmorphism (ICF syndrome) is a rare autosomal recessive disease characterised by facial dysmorphism, immunoglobulin deficiency and branching of chromosomes 1, 9 and 16 after PHA stimulation of lymphocytes. Hypomethylation of DNA of a small fraction of the genome is an unusual feature of ICF patients which is explained by mutations in the DNA methyltransferase gene DNMT3B in some, but not all, ICF patients. OBJECTIVE: To obtain a comprehensive description of the clinical features of this syndrome as well as genotype-phenotype correlations in ICF patients. METHODS: Data on ICF patients were obtained by literature search and additional information by means of questionnaires to corresponding authors. RESULTS AND CONCLUSIONS: 45 patients all with proven centromeric instability were included in this study. Facial dysmorphism was found to be a common characteristic (n = 41/42), especially epicanthic folds, hypertelorism, flat nasal bridge and low set ears. Hypo- or agammaglobulinaemia was demonstrated in nearly all patients (n = 39/44). Opportunistic infections were seen in several patients, pointing to a T cell dysfunction. Haematological malignancy was documented in two patients. Life expectancy of ICF patients is poor, especially those with severe infections in infancy or chronic gastrointestinal problems and failure to thrive. Early diagnosis of ICF is important since early introduction of immunoglobulin supplementation can improve the course of the disease. Allogeneic stem cell transplantation should be considered as a therapeutic option in patients with severe infections or failure to thrive. Only 19 of 34 patients showed mutations in DNMT3B, suggesting genetic heterogeneity. No genotype-phenotype correlation was found between patients with and without DNMT3B mutations.


Assuntos
Instabilidade Cromossômica , Anormalidades Craniofaciais/genética , Síndromes de Imunodeficiência/genética , Adolescente , Adulto , Centrômero/genética , Criança , Pré-Escolar , Anormalidades Craniofaciais/patologia , DNA (Citosina-5-)-Metiltransferases/genética , Feminino , Genótipo , Humanos , Lactente , Masculino , Mutação , Fenótipo , Síndrome , DNA Metiltransferase 3B
4.
Neuromuscul Disord ; 16(11): 766-9, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17005397

RESUMO

Facioscapulohumeral muscular dystrophy (FSHD) is associated with a contraction of the D4Z4 allele on chromosome 4qter. There is also marked DNA hypomethylation of the D4Z4 allele. The DNA hypomethylation may have a central role in the pathogenesis of FSHD. Supplemental folic acid can boost DNA methylation. We evaluated the effect of oral folic acid and methionine supplementation on the methylation level of 4qter D4Z4 alleles in peripheral-blood lymphocytes of nine patients affected with FSHD and six healthy controls. Methylation levels did not change, while recommended serum-folate concentrations were reached.


Assuntos
Alelos , Metilação de DNA/efeitos dos fármacos , Ácido Fólico/farmacologia , Metionina/farmacologia , Distrofia Muscular Facioescapuloumeral/genética , Adolescente , Adulto , Estudos de Casos e Controles , DNA/genética , Suplementos Nutricionais , Feminino , Ácido Fólico/administração & dosagem , Ácido Fólico/sangue , Humanos , Masculino , Metionina/administração & dosagem , Pessoa de Meia-Idade , Músculo Esquelético/metabolismo , Distrofia Muscular Facioescapuloumeral/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Projetos Piloto
6.
FEBS Lett ; 282(1): 53-5, 1991 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-2026265

RESUMO

Flavonoids activate nod gene expression in Rhizobium resulting in the synthesis of Nod signals which trigger organogenesis in the host plant. This paper shows that nod-inducers also stimulate the production of the phytohormone IAA (indole-3-acetic acid).


Assuntos
Flavanonas , Flavonoides/metabolismo , Hesperidina , Ácidos Indolacéticos/metabolismo , Rhizobium/metabolismo , Cromatografia Líquida de Alta Pressão , Regulação Bacteriana da Expressão Gênica , Isoflavonas/metabolismo , Cinética , Luteolina , Rhizobium/genética
7.
Acta Clin Belg ; 69(3): 208-9, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24820920

RESUMO

Reversible lesions of the splenium of the corpus callosum constitute a clinicoradiological syndrome that has been associated to various medical conditions. We report the case of a 47-year-old man who presented with encephalopathy associated to auto-immune thyroid disease in which a reversible splenial lesion was isolated. Although encephalopathy associated to auto-immune thyroid disease is characterized by variable radiological findings, it has only been once associated with a reversible splenial lesion.


Assuntos
Encefalopatias/diagnóstico , Encefalopatias/etiologia , Corpo Caloso , Doença de Hashimoto/diagnóstico , Doença de Hashimoto/etiologia , Encefalopatias/terapia , Encefalite , Doença de Hashimoto/terapia , Humanos , Masculino , Pessoa de Meia-Idade
8.
Waste Manag ; 33(11): 2416-24, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23810322

RESUMO

Due to ongoing developments in the EU waste policy, Waste-to-Energy (WtE) plants are to be optimized beyond current acceptance levels. In this paper, a non-exhaustive overview of advanced technical improvements is presented and illustrated with facts and figures from state-of-the-art combustion plants for municipal solid waste (MSW). Some of the data included originate from regular WtE plant operation - before and after optimisation - as well as from defined plant-scale research. Aspects of energy efficiency and (re-)use of chemicals, resources and materials are discussed and support, in light of best available techniques (BAT), the idea that WtE plant performance still can be improved significantly, without direct need for expensive techniques, tools or re-design. In first instance, diagnostic skills and a thorough understanding of processes and operations allow for reclaiming the silent optimisation potential.


Assuntos
Fontes Geradoras de Energia , Incineração , Compostos de Cálcio/química , Compostos de Nitrogênio/química , Óxidos/química
9.
Neurology ; 75(17): 1548-54, 2010 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-20975055

RESUMO

OBJECTIVE: In some 5% of patients with facioscapulohumeral muscular dystrophy (FSHD), no D4Z4 repeat contraction on chromosome 4q35 is observed. Such patients, termed patients with FSHD2, show loss of DNA methylation and heterochromatin markers at the D4Z4 repeat that are similar to patients with D4Z4 contractions (FSHD1). This commonality suggests that a change in D4Z4 chromatin structure unifies FSHD1 and FSHD2. The aim of our study was to critically evaluate the clinical features in patients with FSHD2 in order to establish whether these patients are phenotypically identical to FSHD1 and to establish the effects of the (epi-) genotype on the phenotype. METHODS: This cross-sectional study studied 33 patients with FSHD2 from 27 families, the largest cohort described to date. All patients were clinically assessed using a standardized clinical evaluation form. Genotype analysis was performed by pulsed field gel electrophoresis and PCR; D4Z4 methylation was studied by methylation-sensitive Southern blot analysis. RESULTS: FSHD2 is identical to FSHD1 in its clinical presentation. Notable differences include a higher incidence (67%) of sporadic cases and the absence of gender differences in disease severity in FSHD2. Overall, average disease severity in FSHD2 was similar to that reported in FSHD1 and was not influenced by D4Z4 repeat size. In FSHD2, a small effect of the degree of hypomethylation on disease severity was observed. CONCLUSIONS: Clinically, patients with FSHD2 are indistinguishable from patients with FSHD1. The present data suggest that FSHD1 and FSHD2 are the result of the same pathophysiologic process.


Assuntos
Distrofia Muscular Facioescapuloumeral/genética , Distrofia Muscular Facioescapuloumeral/fisiopatologia , Proteínas Nucleares/genética , Adolescente , Adulto , Criança , Pré-Escolar , Cromossomos Humanos Par 4 , Estudos de Coortes , Estudos Transversais , Metilação de DNA/genética , Expansão das Repetições de DNA/genética , Saúde da Família , Feminino , Genótipo , Humanos , Lactente , Recém-Nascido , Masculino , Proteínas dos Microfilamentos , Pessoa de Meia-Idade , Fenótipo , Polimorfismo Genético/genética , Proteínas de Ligação a RNA , Adulto Jovem
11.
Cardiovasc J Afr ; 19(3): 141-4, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18568173

RESUMO

AIM: Ischaemia-modified albumin (IMA), as measured by the albumin-cobalt binding (ACB) test, has been cleared by the US Food and Drug administration as a biomarker to exclude the presence of myocardial ischaemia in patients. Although there are a number of published studies detailing the clinical utility of IMA, data on the biological variation of IMA are still lacking. In this study we determined the analytical and biological variance components of ischaemia modified albumin, and compared the distribution of IMA values in our patient population to those provided by the kit manufacturer. METHODS: IMA was determined once a week for five consecutive weeks on a cohort of healthy subjects using a colorimetric method, the A CB test on a Roche modular analyser. RESULTS: The analytical coefficient of variation (CV(A)) was 5%, and the within-subject (CV(I)) and between-subject (CV(G)) biological variations were 3 and 7%, respectively. Analysis of the repeated measures with gender and race (black and Caucasian) as between-subject factors, and weeks (1-5) as the within-subject factor showed that gender had no significant effect on circulating IMA concentrations (p = 0.3146), whereas race did have a significant effect (p = 0.0062). A significant (p = 0.0185) interaction was observed between gender and race. CONCLUSION: The ACB test could bring a new dimension to the care and management of patients with acute coronary syndrome. Further studies for normal population distributions by gender and ethnicity, and an optimum cut-off value appear to be required.


Assuntos
Cobalto , Isquemia Miocárdica/diagnóstico , Kit de Reagentes para Diagnóstico/normas , Albumina Sérica/metabolismo , Adulto , Negro ou Afro-Americano , Biomarcadores/sangue , Estudos de Coortes , Colorimetria/normas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Isquemia Miocárdica/sangue , Isquemia Miocárdica/etnologia , Valor Preditivo dos Testes , Ligação Proteica , Valores de Referência , Reprodutibilidade dos Testes , Fatores Sexuais , População Branca
12.
Neurology ; 69(10): 1018-26, 2007 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-17785671

RESUMO

BACKGROUND: Patients with facioscapulohumeral muscular dystrophy (FSHD) show a contraction of the D4Z4 repeat array in the subtelomere of chromosome 4q. This D4Z4 contraction is associated with significant allele-specific hypomethylation of the repeat. Hypomethylation of D4Z4 is also observed in patients with phenotypic FSHD without contraction of D4Z4 and in patients with the immunodeficiency, centromeric instability, and facial anomalies (ICF) syndrome, an unrelated disease that does not present with muscular dystrophy and is in part caused by DNMT3B mutations. METHODS: In order to identify the gene defect and to find the pathogenetic epigenetic pathway in phenotypic FSHD, we have aimed to identify the differences and commonalities in phenotypic FSHD and ICF by 1) investigation of DNA methylation of non-D4Z4 repeat arrays, 2) analysis of mitogen-stimulated lymphocytes to detect pericentromeric abnormalities involving chromosomes 1, 9, and 16, 3) determination of IgA, IgG, and IgM levels, and 4) mutational analysis of candidate genes to identify a second disease locus involved in the pathogenesis of phenotypic FSHD. RESULTS: Our results do not show epigenetic or phenotypic commonalities between phenotypic FSHD and ICF other than the earlier observed D4Z4 hypomethylation. We could not identify any mutations in the candidate genes tested for. CONCLUSION: Our data suggest that in phenotypic FSHD hypomethylation is restricted to D4Z4 and that phenotypic FSHD and ICF do not share a defect in the same molecular pathway.


Assuntos
Cromossomos Humanos Par 4/genética , Metilação de DNA , Distrofia Muscular Facioescapuloumeral/genética , Fenótipo , Sequências de Repetição em Tandem/genética , Adulto , Idoso , Alelos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Distrofia Muscular Facioescapuloumeral/metabolismo , Mutação , Linhagem
13.
Am J Med Genet A ; 143A(17): 2052-7, 2007 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-17702009

RESUMO

We report on two sibs with ICF syndrome (immunodeficiency, centromeric heterochromatin instability, and facial anomalies) diagnosed in the elder brother based on the typical chromosomal abnormalities present in 56% of metaphases from cultured lymphocytes. In a previous cytogenetic analysis this diagnosis had been missed due to low manifestation of the ICF chromosomal phenotype. Hypomethylation of classical satellites 2 and 3, and of alpha-satellite DNA was shown in the lymphocytes of the younger sister. At 7 years of age the boy presented with hemiplegia due to tumerous invasion of the right brachial plexus. Histopathology revealed classical Hodgkin lymphoma, a neoplasia which might have been facilitated by the underlying genetic defect.


Assuntos
Instabilidade Cromossômica/genética , Ossos Faciais/anormalidades , Variação Genética , Doença de Hodgkin/genética , Síndromes de Imunodeficiência/genética , Fenótipo , Centrômero/genética , Criança , Pré-Escolar , Feminino , Heterocromatina/genética , Doença de Hodgkin/diagnóstico , Humanos , Síndromes de Imunodeficiência/diagnóstico , Masculino
14.
Planta ; 104(3): 272-4, 1972 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24481741

RESUMO

Far-red light was demonstrated to accelerate senescence in mature, green tissue of intact thalli of Marchantia polymorpha. The red/far-red reversibility of this phenomenon proves the involvement of phytochrome. As a daily exposure to 5 min red light is sufficient to prevent aging of the tissue, photosynthesis does not play a specific role in this response.

15.
Plant Physiol ; 47(4): 457-64, 1971 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16657643

RESUMO

Eight-day-old dark-grown bean leaves were greened by prolonged irradiation with far red light. Growth, chlorophyll content, oxygen-evolving capacity, photophosphorylation capacity, chloroplast structure (by electron microscopy), and in vivo forms of chlorophyll (by low temperature absorption and derivative spectroscopy on intact leaves) were followed during the greening process. Chlorophyll a accumulated slowly but continuously during the 7 days of the experiment (each day consisted of 12 hours of far red light and 12 hours of darkness). Chlorophyll b was not detected until the 5th day. The capacity for oxygen evolution and photophosphorylation began at about the 2nd day. Electron microscopy showed little formation of grana during the 7 days but rather unfused stacks of primary thylakoids. The thylakoids would fuse to give grana if the leaves were placed subsequently in white light. The low temperature spectroscopy of intact leaves showed that the chlorophyll a was differentiated into three forms with absorption maxima near 670, 677, and 683 nanometers at -196 C during the first few hours and that these forms accumulated throughout the greening process. Small amounts of two longer wavelength forms with maxima near 690 and 698 nanometers appeared at about the same time as photosynthetic activity.

16.
Plant Physiol ; 48(4): 407-12, 1971 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16657809

RESUMO

Mature green tissue of Marchantia polymorpha L. bleaches markedly when placed in continuous darkness for 4 days but remains green when given daily 1-hour photoperiods of white light. The tissue, however, is induced to bleach when each daily 1-hour photoperiod is terminated with a brief irradiation with far red light. The bleaching does not occur when each irradiation with far red light is followed by a brief irradiation with red light. The bleaching is taken as an index of senescence since the loss of chlorophyll in the bleached tissue is accompanied by a breakdown of cell organelles and cytoplasm. Phytochrome is clearly implicated in the control of senescence by light. It was also found that 5 minutes of red light given once a day was as effective as the 1-hour photoperiods with white light in preventing the bleaching and that bleaching was induced when each daily 5-minute irradiation with red light was followed by a 10-minute irradiation with far red light.

17.
Plant Physiol ; 84(3): 707-10, 1987 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16665507

RESUMO

Water uptake of seeds of Phaseolus vulgaris L. cv Limburg was monitored in a controlled atmosphere every day at solar noon for a period of 2 years. The imbibition rate, determined as the mean of five replicas, was related to the lunar cycle, maximal water uptake occurring between the new phases of the cycle. The monthly mean value of imbibition rate, calculated from the daily measurements, displayed a circannual rhythm reaching maximal values in August-September and minimal values in February-March. These monthly values were positively correlated with the mean of the maximal temperatures recorded daily outside.

18.
Plant Physiol ; 86(3): 836-40, 1988 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16665997

RESUMO

Aechmea victoriana var discolor L. B. Foster and Aechmea dactylina Bal. are commercially propagated in vitro through lateral shoot growth. A modified Murashige and Skoog medium is used which contains both BA and IAA. These growth substances were shown in the present study to synergistically stimulate the production of ethylene by the cultured plants. The stimulation of ethylene production is correlated with the outgrowth of the lateral buds. The rise in ethylene production was concluded to induce lateral shoot growth, because: (a) outgrowth of the shoots was blocked by preventing an increase in ethylene production, (b) 1-aminocyclopropane-1-carboxylic acid (ACC), the natural precursor of ethylene biosynthesis, substituted for IAA in the promotion of ethylene production and lateral bud outgrowth. Although ACC could substitute for IAA, it could not substitute for BA; therefore, cytokinins are concluded to be essential for lateral bud outgrowth in vitro in Aechmea. These results suggest that cytokinins and ethylene both play roles in natural lateral bud initiation and that the cytokinin function involves two stages of the process.

19.
Plant Physiol ; 93(1): 333-8, 1990 May.
Artigo em Inglês | MEDLINE | ID: mdl-16667456

RESUMO

Two brief red (R) irradiations, separated by 24 hours, given to Kalanchoë blossfeldiana Poelln. cv Feuerblüte seeds, made secondarily dormant by a prolonged dark incubation period on water and transferred to GA(3), induce very low germination. Some effect of these irradiations is preserved, however, during a long dark interval in fully imbibed seeds and greatly increases the germination induced by another brief R exposure. This long-lasting light effect is, at 20 degrees C, only lost after a dark interval of about 1 month. It can also be induced by two brief far-red (FR) exposures. Its preservation is temperature-dependent, low temperatures being favorable. Light-induced changes in the ATP-content were demonstrated during preservation and expression of the long-lasting light effect, indicating a long-lasting metabolic change. In seeds with primary dormancy sown on GA(3), an analogous long-lasting light effect is induced by one or two brief R or FR irradiations, even when they are given before germination can take place. The presence of GA(3), which was shown to induce a very low fluence germination response in Kalanchoë seeds, is required for the occurrence of the long-lasting light effect. The data suggest long-term preservation of some effect(s) of Pfr rather than persistent presence of Pfr itself.

20.
Plant Physiol ; 94(4): 1616-24, 1990 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16667895

RESUMO

The effect of plant water deficit on ethylene production by intact plants was tested in three species, beans (Phaseolus vulgaris L.), cotton (Gossypium hirsutum L.) and miniature rose (Rosa hybrida L., cv Bluesette). Compressed air was passed through glass, plant-containing cuvettes, ethylene collected on chilled columns, and subsequently assayed by gas chromatography. The usual result was that low water potential did not promote ethylene production. When plants were subjected to cessation of irrigation, ethylene production decreased on a per plant or dry weight basis of calculation. No significant promotion of ethylene production above control levels was detected when water deficit-treated bean or cotton plants were rewatered. The one exception to this was for cotton subjected to a range of water deficits, plants subjected to deficits of -1.4 to -1.6 MPa exhibited a transient increase of ethylene production of 40 to 50% above control levels at 24 or 48 hours. Ethylene was collected from intact leaves while plants developed a water deficit stress of -2.9 megapascals after rewatering, and no significant promotion of ethylene production was detected. The shoots of fruited, flowering cotton plants produced less ethylene when subjected to cessation of irrigation. In contrast, the ability of bench drying of detached leaves to increase ethylene production several-fold was verified for both beans and cotton. The data indicate that detached leaves react differently to rapid drying than intact plants react to drying of the soil with regard to ethylene production. This result suggests the need for additional attention to ethylene as a complicating factor in experiments employing excised plant parts and the need to verify the relevance of shock stresses in model systems.

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