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1.
Osteoarthritis Cartilage ; 24(11): 1890-1897, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27374877

RESUMO

OBJECTIVE: In patients with traumatic knee distorsion and hemarthrosis, to investigate the panorama of structural injury, as visualized on magnetic resonance imaging (MRI). DESIGN: Cohort study of 1145 consecutive patients with traumatic knee distorsion who underwent MRI within median 8 days after injury. We present structural injury as visualized on MRI in relation to age, sex and activity at injury. Population based gender specific annual incidences of common structural injuries were calculated. RESULTS: The majority of injuries (72%) occurred during sports. Overall, anterior cruciate ligament (ACL) rupture was the most common structural injury (52%), followed by meniscal tear (41%) and lateral patella dislocation (LPD, 17%). Only 12% of ACL tears were isolated with meniscal tear being the most common associated injury (55%). The annual incidence of ACL injury was 77 (70-85, 95% CI) per 100,000 inhabitants with significant differences between men (91, 80-103) and women (63, 53-73). In those aged 16 years and younger, LPD was the most frequent structural injury, both in boys (39%) and girls (43%). In this age group, the annual incidence of LPD was 88 (68-113) and higher in boys (113, 81-154) than in girls (62, 39-95). CONCLUSIONS: ACL injury occurs in one out of two knees with traumatic hemarthrosis but only 12% are without concomitant structural injury. The overall rate of traumatic knee hemarthrosis and ACL injury is higher in men. In those aged 10-19 years, ACL rupture is more common among girls than boys whereas in those 16 years and younger, LPD is more common among boys than girls.


Assuntos
Hemartrose , Estudos de Coortes , Feminino , Humanos , Traumatismos do Joelho , Articulação do Joelho , Imageamento por Ressonância Magnética , Masculino
2.
J Hosp Infect ; 139: 134-140, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37419188

RESUMO

BACKGROUND: Previous studies on hospital-acquired influenza (HAI) have not systematically evaluated the possible impact of different influenza subtypes. HAI has historically been associated with high mortality, but clinical consequences may be less severe in a modern hospital setting. AIMS: To identify and quantify HAI for each season, investigate possible associations with varying influenza subtypes, and to determine HAI-associated mortality. METHODS: All influenza-PCR-positive adult patients (>18 years old) hospitalized in Skåne County during 2013-2019, were prospectively included in the study. Positive influenza samples were subtyped. Medical records of patients with suspected HAI were examined to confirm a nosocomial origin and to determine 30-day mortality. RESULTS: Of 4110 hospitalized patients with a positive influenza PCR, 430 (10.5%) were HAI. Influenza A(H3N2) infections were more often HAI (15.1%) than influenza A(H1N1)pdm09, and influenza B (6.3% and 6.8% respectively, P<0.001). The majority of HAI caused by H3N2 were clustered (73.3 %) and were the cause of all 20 hospital outbreaks consisting of ≥4 affected patients. In contrast, the majority of HAI caused by influenza A(H1N1)pdm09 and influenza B were solitary cases (60% and 63.2%, respectively, P<0.001). Mortality associated with HAI was 9.3% and similar between subtypes. CONCLUSIONS: HAI caused by influenza A(H3N2) was associated with an increased risk of hospital dissemination. Our study is relevant for future seasonal influenza infection control preparedness and shows that subtyping of influenza may help to define relevant infection control measures. Mortality in HAI remains substantial in a modern hospital setting.


Assuntos
Vírus da Influenza A Subtipo H1N1 , Vacinas contra Influenza , Influenza Humana , Adulto , Humanos , Adolescente , Influenza Humana/epidemiologia , Vírus da Influenza A Subtipo H3N2 , Estações do Ano , Hospitais
3.
J Proteomics ; 218: 103688, 2020 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-32061841

RESUMO

Fusarium species are cereal pathogens that cause the Fusarium Head Blight (FHB) disease. FHB can reduce yield, cause mycotoxin accumulation in the grain and reduce germination efficiency of the harvested seeds. Understanding the biochemical interactions between the host plants and the pathogen is crucial for controlling the disease and for the development of cultivars with improved tolerance to FHB. Here, we studied morphological and proteomic differences between the susceptible oat variety Belinda and the more resistant variety Argamak using variety-specific transcriptome assemblies as references. Measurements of deoxynivalenol toxin levels confirmed the partial resistance in Argamak and the susceptibility in Belinda. To jointly investigate the proteomics- and sequence data, we developed an RShiny-based interface for interactive exploration of the dataset using univariate and multivariate statistics. When applying this interface to the dataset, quantitative protein differences between Belinda and Argamak were detected, and eighteen peptides were found uniquely in Argamak during infection, among them several lipoxygenases. Such proteins can be developed as markers for Fusarium resistance breeding. In conclusion, this study provides the first proteogenomic insight on molecular Fusarium-oat interactions at both morphological and molecular levels and the data are openly available through an interactive interface for further inspection. SIGNIFICANCE: Fusarium head blight causes widespread damage to crops, and chronic and acute toxicity to human and livestock due to the accumulation of toxins during infection. In the present study, two oat varieties with differing resistance were challenged with Fusarium to understand the disease better, and studied both at morphological and molecular levels, identifying proteins which could play a role in the defense mechanism. Furthermore, a proteogenomics approach allows joint profiling of expression and sequence level differences to identify potentially functionally differing mutations. Here such analysis is made openly available through an interactive interface which allows other scientists to draw further findings from the data. This study may both serve as a basis for understanding oat disease response and developing breeding markers for Fusarium resistant oat and future proteogenomic studies using the interactive approach described.


Assuntos
Fusarium , Proteogenômica , Avena , Humanos , Melhoramento Vegetal , Doenças das Plantas/genética , Proteômica , Triticum
4.
Sci Total Environ ; 695: 133808, 2019 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-31426002

RESUMO

In this study, emission spectra of three different commonly used xenon irradiation sources were analyzed and compared for the first time to ascertain the most suitable setup to simulate natural solar radiation. In order to demonstrate setup differences, absolute photon fluxes of irradiation sources were received by actinometry. Verification was done by measuring quantum yields of the model compounds Penconazole, Terbutryn, and Mecoprop in every setup. Differences regarding kinetic aspects and the formation of transformation products (TPs) was evaluated by analyzing direct phototransformation and additionally photolysis in presence of Nitrate as a photosensitizer in one irradiation setup (optical bench). Results showed that a precise setup characterization is needed to estimate whether irradiation sources are suitable to simulate terrestrial sunlight. This was found to be especially important for weakly sunlight-absorbing substances. In comparison with direct photolysis, indirect photolysis led to an enhancement of degradation rate constants for all substances and in case of Mecoprop to different types of TPs that were formed during irradiation. This study underlined that there are big knowledge gaps regarding irradiation sources setups and conditions. It is therefore absolutely necessary to consider those factors while simulating substance degradation and the TP formation under environmental conditions.

5.
Sci Total Environ ; 697: 134048, 2019 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-32380599

RESUMO

The treatment with ultraviolet (UV) light is a well-known technique for water disinfection. Photodegradation by UV light is in discussion as measure for advanced water treatment that could provide a potential removal option for micropollutants. Micropollutants such as ingredients from personal care products are also present in grey water. Grey water gets increasingly attention as a source for water reuse. For that purpose it has to be treated. UV-treatment is an option. However, the knowledge on the fate of micropollutants within such a treatment is little. Therefore, we investigated the fate of the UV filters ethylhexyl methoxycinnamate (EHMC), and octocrylene (OCR) as for both UV filters the presence in grey water was reported. OCR as a single compound was investigated with regard to its degradation kinetics and possible photo-transformation products (photo-TPs). These results were compared with those of EHMC previously reported in literature. The mixture of the two UV filters was also investigated to reveal if mixture effects occur regarding the elimination of the UV filters and the formation of TPs. A medium pressure mercury vapor lamp (200-400 nm) was employed for photolysis. This study shows that OCR itself was eliminated below the limit of detection after 256 min and that photo-TPs were formed. The photolysis of the mixture demonstrated alterations of the degradation rates and patterns. Additional TPs were formed by the reaction of the UV filters or TPs with each other. The study shows that more attention should be paid to mixture-effects and mixture-TPs that may cause further follow-up effects.

6.
Infect Dis (Lond) ; 50(9): 678-686, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29620426

RESUMO

BACKGROUND/AIM: Treatment of latently infected individuals at increased risk of reactivation is a cornerstone in tuberculosis control. Although asylum seekers without residence permit in Sweden are offered screening for both active tuberculosis and latent tuberculosis infection (LTBI), treatment for LTBI is often not initiated due to anticipated low rates of treatment completion. We aimed to compare completion rates for LTBI treatment between asylum seekers and other patients, and between asylum seekers with and without residence permit. METHODS: Data were collected retrospectively from tuberculosis clinic registers and medical records. For comparison of treatment completion rates, relative risks (RR) and confidence intervals (CI) were calculated. Predictors of completion were assessed by logistic regression multivariate analysis. RESULTS: Treatment completion was achieved in 506/606 subjects (83%). RR of non-completion for asylum seekers (n = 297) compared to other subjects (n = 309) was 1.13 (95% CI: 0.79-1.61; p = .51), and 0.91 (95% CI: 0.53-1.56; p = .72) for asylum seekers without residence permit (n = 217) compared to asylum seekers with residence permit (n = 80). Completion rates increased from 53% in 2008 to 92% in 2015-2016. The following factors were associated with completion: scheduled interpreter-assisted appointments throughout the course of therapy, shorter treatment duration (6 vs. 9 months), and being treated in connection with immunosuppressive therapy. CONCLUSION: Treatment completion rates were similar between asylum seekers and other subjects, supporting initiation of latent tuberculosis treatment in immigrants with recent arrival to low-endemic countries.


Assuntos
Emigrantes e Imigrantes/estatística & dados numéricos , Tuberculose Latente/tratamento farmacológico , Refugiados/estatística & dados numéricos , Adolescente , Adulto , Antituberculosos/uso terapêutico , Criança , Pré-Escolar , Feminino , Hospitais Universitários , Humanos , Lactente , Recém-Nascido , Tuberculose Latente/diagnóstico , Masculino , Programas de Rastreamento/estatística & dados numéricos , Análise Multivariada , Estudos Retrospectivos , Suécia , Adulto Jovem
7.
J Clin Invest ; 87(6): 2191-6, 1991 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-1904073

RESUMO

Myasthenia gravis (MG) is strongly associated with antibodies to acetylcholine receptor (AChR), whereas the extent of T cell involvement is not settled. The number of cells secreting interferon-gamma (IFN-gamma) in response to AChR during 48 h culture of blood mononuclear cells (PBL) may reflect AChR-reactive T cells. Using an immunospot assay, we detected such cells in 23 of 30 patients with MG at a mean number of 1 per 33.333 PBL. AChR-reactive T cells were also found in patients with other neurological diseases (OND) and in healthy subjects but at lower frequencies and numbers. The T cell response to purified protein derivative and to PHA, and also to two major myelin proteins (basic protein and proteolipid protein) did not differ between MG and the two control groups, underlining the specificity of an augmented T cell reactivity to AChR in MG. Evaluation of the B cell response by enumerating anti-AChR IgG antibody secreting cells revealed such cells in 27 of 28 patients with MG at a mean value of 1 per 14,085 PBL. Cells secreting anti-AChR antibodies of the IgA and IgM isotypes were also detected in MG, but less frequently, at lower numbers, and only in conjunction with IgG antibody secreting cells. Anti-AChR antibody secreting cells were also found among patient with OND and in healthy controls, but at lower frequencies and numbers. These data confirm that AChR is a major target for autoimmune response in MG.


Assuntos
Linfócitos B/imunologia , Miastenia Gravis/imunologia , Receptores de Antígenos de Linfócitos B/imunologia , Receptores de Antígenos de Linfócitos T/imunologia , Receptores Nicotínicos/imunologia , Linfócitos T/imunologia , Feminino , Humanos , Isotipos de Imunoglobulinas , Interferon gama/metabolismo , Contagem de Leucócitos , Masculino , Doenças do Sistema Nervoso/imunologia , Timectomia
8.
Nat Biotechnol ; 18(7): 784-8, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10888850

RESUMO

In most tree-breeding programs worldwide, increasing the trees' growth rates and stem volumes and shortening their rotation times are important aims. Such trees would yield more biomass per unit area. Here we show that overexpressing a key regulatory gene in the biosynthesis of the plant hormone gibberellin (GA) in hybrid aspen (Populus tremula x P. tremuloides) improves growth rate and biomass. In addition, these transgenic trees have more numerous and longer xylem fibers than unmodified wild-type (wt) plants. Long fibers are desirable in the production of strong paper, but it has not as yet proved possible to influence this trait by traditional breeding techniques. We also show that GA has an antagonistic effect on root initiation, as the transgenic lines showed poorer rooting than the control plants when potted in soil. However, the negative effect on rooting efficiencies in the initial establishment of young plantlets in the growth chamber did not significantly affect root growth at later stages.


Assuntos
Giberelinas/biossíntese , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Árvores/genética , Northern Blotting , Cromatografia Gasosa-Espectrometria de Massas , Vetores Genéticos , Oxigenases de Função Mista/biossíntese , Modelos Químicos , Fatores de Tempo , Transformação Genética , Árvores/crescimento & desenvolvimento , Árvores/fisiologia
9.
Cancer Res ; 42(9): 3851-7, 1982 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-6286114

RESUMO

Peritoneal macrophages from BD IX rats collected 24 hr after an i.p. injection of ADriamycin (10 mg/kg) were cytotoxic to syngeneic cancer cells in culture. In contrast, incubation in vitro in Adriamycin solutions did not evoke tumoricidal activity in peritoneal macrophages, whatever the incubation time (from 1 to 24 hr) and the Adriamycin concentration (from 1 ng to 100 micrograms/ml). Macrophages incubated with Adriamycin in vitro accumulated the drug in their nuclei, whereas macrophages from animals receiving Adriamycin in vivo accumulated it is cytoplasmic vacuoles. Early observation of peritoneal cells after in vivo exposure to Adriamycin shows that Adriamycin is concentrated in mast cell granules which are released and then phagocytosed by peritoneal macrophages. Mast cells exposed to Adriamycin in vitro can induce macrophages to become cytotoxic. These facts explain the difference between macrophages exposed to Adriamycin in vivo and in vitro. Adriamycin fluorescence appears in nuclei of cancer cells incubated with in vivo-labeled macrophages, suggesting that macrophages can directly transfer the drug into cancer cells and therefore play a role in the Adriamycin antitumor effect.


Assuntos
Neoplasias do Colo/patologia , Doxorrubicina/farmacologia , Macrófagos/fisiologia , Mastócitos/metabolismo , Animais , Líquido Ascítico/citologia , Núcleo Celular/metabolismo , Sobrevivência Celular , Células Cultivadas , Grânulos Citoplasmáticos/metabolismo , Doxorrubicina/metabolismo , Corpos de Inclusão/metabolismo , Linfócitos/metabolismo , Macrófagos/efeitos dos fármacos , Ratos
10.
Sci Total Environ ; 572: 1092-1100, 2016 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-27531468

RESUMO

To prevent water shortages in the future and to reduce domestic water consumption, decentralized grey water (GW) reuse has become increasingly important. This water has, however, to be free of pollutants. Conventional treatment of GW does not fully eliminate micropollutants such as the UV filter substance ethylhexyl methoxycinnamate (EHMC). EHMC, which is commonly used in sunscreens and personal care products, is an endocrine disruptor and shows potential to bioaccumulation, which is also reflected in its low water solubility. Photolysis has been proposed as an alternative treatment method for other micropollutants, but it is not clear yet whether it can also be used to eliminate EHMC. One goal of this study was to better understand the basic pathways involved in this process. It aimed to identify photo-transformation products (photo-TPs) by using, in the test conditions, an initial concentration of EHMC higher than those expected in the environment. Acetonitrile (ACN) was added in low concentrations to the aqueous solution to overcome the low aquatic solubility of EHMC. The influence of this co-solvent on the degradation kinetics was studied. The photolysis experiments were carried out using a medium pressure mercury lamp, which emits UV light in the range of 200-400nm. The quantum yield of the photolysis of EHMC was 0.0042 and 0.0023mol·Einstein-1 (for 0.2 and 0.5% ACN (v/v), respectively), and the relative and absolute UV photon fluxes were determined. HPLC was used to monitor the elimination kinetics of EHMC, which followed first-order kinetics. The results of LC-MSn analyses revealed that beside others, several oxidized and hydroxylized EHMC isomers were formed as photo-TPs in aqueous solution. Using a set of in silico quantitative structure-activity relationship (QSAR) models, this study also offered new insights concerning the environmental fate and toxicity of the TPs of EHMC.


Assuntos
Cinamatos/toxicidade , Conservação dos Recursos Hídricos , Disruptores Endócrinos/toxicidade , Fotólise , Protetores Solares/toxicidade , Poluentes Químicos da Água/toxicidade , Cinamatos/química , Disruptores Endócrinos/química , Relação Quantitativa Estrutura-Atividade , Protetores Solares/química , Testes de Toxicidade/métodos , Raios Ultravioleta , Eliminação de Resíduos Líquidos , Poluentes Químicos da Água/química
11.
Biochim Biophys Acta ; 1447(2-3): 185-98, 1999 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-10542315

RESUMO

Sixteen ultraviolet-B radiation-regulated pea genes were identified. Functionally, the corresponding proteins were divided into four groups. (i) Chloroplast-localized proteins. Genes for these proteins were down-regulated, underlining the deleterious effects of UV-B on this organelle. A novel down-regulated photosystem I light-harvesting chlorophyll a/b-binding protein gene (PsLhcA4), was cloned and sequenced. (ii) Protein turnover enzymes. Levels of mature mRNAs for the PU1 and PsUBC4 genes, encoding proteins of the ubiquitin protein degradation pathway, were up- and down-regulated, respectively, implying alteration of plant cell protein content by changes in both gene expression and protein degradation. (iii) Proteins involved in intracellular signalling. Expression of genes for small GTPases, rab and rho homologues, were altered. (iv) Phenylpropanoid or flavonoid biosynthesis. Expression of three genes encoding enzymes in these pathways were up-regulated and one of them, the novel PsC450R1, was cloned and sequenced. Moreover, unexpected high molecular mass psbA RNA adducts were found to appear after UV-B exposure. In addition, a large increase in corresponding high molecular mass adducts were also found for PsLhcA4, and PsUBC4 mRNA and 23S rRNA. These RNA species do not contain protein and probably appear due to cross-linking of two or more RNA molecules, or are the result of UV-B-induced failure of transcription termination.


Assuntos
Regulação da Expressão Gênica de Plantas/efeitos da radiação , Pisum sativum/genética , Proteínas de Plantas/genética , RNA de Plantas/genética , Sequência de Aminoácidos , Regulação para Baixo , Dados de Sequência Molecular , RNA de Plantas/química , Alinhamento de Sequência , Raios Ultravioleta
12.
Plant Physiol ; 101(1): 313-320, 1993 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12231687

RESUMO

Transgenic plants overproducing indole-3-acetic acid (IAA) from expression of the Agrobacterium tumefaciens T-DNA IAA biosynthesis genes were used to study the conjugation of IAA. At the 11-node stage, free IAA, as well as ester- and amide-conjugated IAA, was analyzed in wild-type tobacco SR1 and in transgenic plants denoted 35S-iaaM/iaaH (line C) and 35S-iaaM x 35S-iaaH (line X). The transgenic plants contained increased levels of both free and conjugated IAA, and the main increase in IAA conjugates occurred in amide conjugates. Two amide conjugates were identified by fritfast atom bombardment liquid chromatography-mass spectrometry as indole-3-acetylaspartic acid (IAAsp) and indole-3-acetylglutamic acid (IAGlu), and one ester conjugate was identified as indole-3-acetylglucose. IAAsp and IAGlu were also identified as endogenous substances in wild-type plants. In wild-type plants, the percent of total IAA in the free form was significantly higher in young leaves (73 [plus or minus] 7%, SD) than in old leaves (36 [plus or minus] 8%), whereas there was no difference between young (73 [plus or minus] 8%) and old internodes (70 [plus or minus] 9%). In IAA-overproducing transformants, both free and conjugated IAA levels were increased, but the percent free IAA was maintained constant (57 [plus or minus] 10%) for both leaves and internodes, independent of the total IAA level or tissue age. These results suggest that synthesis or transport of IAA conjugates is regulated in the vegetative wild-type plant, and that different organs possess a unique balance between free and conjugated IAA. The IAA-overproducing plant, however, acquires a lower proportion of free IAA in the stem and younger leaves, presumably determined by a higher conjugation in those tissues compared with wild type.

13.
Plant Physiol ; 102(2): 363-371, 1993 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12231827

RESUMO

Transgenic tobacco (Nicotiana tabacum L. cv Wisconsin 38) plants expressing the Agrobacterium rhizogenes rolC gene under the control of the cauliflower mosaic virus 35S RNA promoter were constructed. These plants displayed several morphological alterations reminiscent of changes in indole-3-acetic acid (IAA), cytokinin, and gibberellin (GA) content. However, investigations showed that neither the IAA pool size nor its rate of turnover were altered significantly in the rolC plants. The biggest difference between rolC and wild-type plants was in the concentrations of the cytokinin, isopentenyladenosine (iPA) and the gibberellin GA19. Radio-immunoassay and liquid chromatography-mass spectrometry measurements revealed a drastic reduction in rolC plants of iPA as well as in several other cytokinins tested, suggesting a possible reduction in the synthesis rate of cytokinins. Furthermore, gas chromatography-mass spectrometry quantifications of GA19 showed a 5- to 6-fold increase in rolC plants compared with wild-type plants, indicating a reduced activity of the GA19 oxidase, a proposed regulatory step in the gibberellin biosynthesis. Thus, we conclude that RolC activity in transgenic plants leads to major alterations in the metabolism of cytokinins and gibberellins.

14.
Plant Physiol ; 112(2): 493-502, 1996 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12226405

RESUMO

We have altered the growth and development of a deciduous forest tree by transforming hybrid aspen (Populus tremula x Populus tremuloides) with the Agrobacterium rhizogenes rolC gene expressed under the strong cauliflower mosaic virus 35S promoter. We demonstrate that the genetically manipulated perennial plants, after a period of dormancy, maintain the induced phenotypical changes during the second growing period. Furthermore, mass-spectrometrical quantifications of the free and conjugated forms of indole-3-acetic acid and cytokinins and several gibberellins on one transgenic line correlate the induced developmental alterations such as stem fasciation to changes in plant hormone metabolism. We also show that the presence of the RolC protein increases the levels of the free cytokinins, but not by a process involving hydrolysis of the inactive cytokinin conjugates.

15.
Plant Physiol ; 109(4): 1179-1189, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12228661

RESUMO

A key regulator of cambial growth is the plant hormone indoleacetic acid (IAA). Here we report on altered wood characteristics and growth patterns in transgenic hybrid aspen (Populus tremula L. x Populus tremuloides Michx.) expressing Agrobacterium tumefaciens T-DNA IAA-biosynthetic iaaM and iaaH genes. Eighteen lines simultaneously expressing both genes were regenerated. Of these, four lines, verified to be transgenic by northern blot analysis, were selected and raised under controlled growth conditions. All four lines were affected in their growth patterns, including alterations in height and stem diameter growth, internode elongation, leaf enlargement, and degree of apical dominance. Two transgenic lines, showing the most distinct phenotypic deviation from the wild type, were characterized in more detail for free and conjugated IAA levels and for wood characteristics. Both lines showed an altered IAA balance, particularly in mature leaves and roots where IAA levels were elevated. They also exhibited changes in wood anatomy, most notably a reduction in vessel size, an increase in vessel density, and changes in ray development. Thus, the recent development of techniques for gene transfer to forest trees enabled us to investigate the influence of an altered IAA balance on xylem development in an intact experimental system. In addition, the results demonstrate the possibility of manipulating wood properties in a forest tree through controlled changes of IAA concentration and distribution.

16.
Sci Total Environ ; 532: 733-43, 2015 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-26119387

RESUMO

Diffuse entry of pesticide residues from agriculture into rivers is spatially unevenly distributed. Therefore, the identification of critical source areas (CSAs) may support water quality management in agricultural catchments. In contrast to former studies, we followed the hypothesis that not only hydrological and topographical characteristics but also physico-chemical properties of pesticide residues have a major influence on their loss to rivers and on corresponding formation of CSAs. We designed a virtual experiment, i.e. a numerical experiment as close as possible to environmental conditions, in a headwater catchment where pronounced spatial differences in hydrological transport processes were identified in the past. 144 scenarios with different combinations of adsorption coefficients (KOC = 10-1000 ml/g) and transformation half-lives (DT50 = 3-60 days) for pesticide parent compounds (PCs) and their transformation products (TPs) were simulated using the catchment-scale spatially distributed reactive transport model ZIN-AgriTra. Export fractions of substances in the virtual experiment ranged from 0.001-15% for pesticides and 0.001-1.8% for TPs. The results of the scenario investigations suggest that more of the calculated export mass variability could be attributed to KOC than to DT50 for both PCs and TPs. CSAs for TPs were spatially more equally distributed in the catchment than for PC export which was likely an effect of changing physico-chemical properties during transformation. The ranking of highest export fields was different between PCs and TPs for most of the investigated scenarios but six fields appeared among the top ten export fields in 95% of the scenarios, which shows the influence of site characteristics such as tile drains or soil properties in the catchment. Thus, the highest export fields were determined by a combination of site characteristics and substance characteristics. Therefore, despite the challenge of widely differing physico-chemical characteristics of pesticides on the market, these characteristics are an important consideration when delineating pesticide residue CSAs.


Assuntos
Monitoramento Ambiental , Modelos Químicos , Praguicidas/análise , Movimentos da Água , Poluentes Químicos da Água/análise
17.
Gene ; 81(2): 335-47, 1989 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-2680771

RESUMO

Luciferase (Lux)-encoding sequences are very useful as reporter genes. However, a drawback when applying Vibrio harveyi Lux as a reporter enzyme in eukaryotic cells, is that it is a heterodimeric enzyme, thus requiring simultaneous synthesis of both Lux subunits to be active. To overcome this disadvantage, luxA and luxB genes encoding the A and B subunits of this light-emitting heterodimeric Lux, were fused and expressed in Escherichia coli. Comparative analysis of four fused monomeric Lux enzymes by in vivo enzyme assay, immunoblotting and partial enzyme purification, showed that the fused Lux were active both as AB or as BA monomers, albeit at different levels (up to 80% activity for AB and up to 2% for BA, as compared with the wild type binary A + B construct). One of the LuxAB fusion proteins was stably expressed in calli of Nicotiana tabacum, and displayed very high Lux activity, thus demonstrating its potential as a reporter enzyme in eukaryotic systems.


Assuntos
Genes Bacterianos/genética , Engenharia Genética/métodos , Luciferases/genética , Vibrio/genética , Sequência de Bases , Cromatografia Líquida de Alta Pressão , Clonagem Molecular , Escherichia coli/genética , Dados de Sequência Molecular , Plantas Tóxicas , Plasmídeos/genética , Mapeamento por Restrição , Nicotiana/genética
18.
J Neuroimmunol ; 25(1): 1-6, 1989 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-2685038

RESUMO

Intrathecal B cell function in healthy subjects has been poorly elucidated. Although there are measurable quantities of immunoglobulins (Ig) in the cerebrospinal fluid (CSF) of 'normal' individuals, it is not clear whether this reflects transudation from serum or is due to some production within the central nervous system. We have therefore isolated cells from CSF to assess the frequency of Ig-secreting cells, utilizing a nitrocellulose immunospot assay for enumeration of the IgG-, IgA- and IgM-producing cells per 10(4) mononuclear cells (MNC) isolated from CSF and blood. Contrary to previous belief, the CSF obtained from 22 of 23 'normal' subjects (95%) with muscular tension headache but no evidence of organic neurological disease contained 2-50 (mean 20) IgG-secreting cells per 10(4) MNC. The corresponding peripheral blood specimens contained 0-6 (mean 3) IgG-secreting cells per 10(4) MNC. The proportion of IgG-secreting cells among MNC is thus about 7-fold higher in CSF than in blood of healthy individuals. IgA- and IgM-producing cells were also found in normal CSF, but less frequently than cells secreting IgG and at proportions similar to those in peripheral blood. We suggest that there is continuous production of Ig of different isotypes in CSF, even in subjects without any signs of neurological disease.


Assuntos
Líquido Cefalorraquidiano/citologia , Cefaleia/etiologia , Imunoglobulinas/metabolismo , Contração Muscular , Adulto , Idoso , Células Sanguíneas/metabolismo , Feminino , Cefaleia/metabolismo , Cefaleia/patologia , Humanos , Imunoglobulina A/metabolismo , Imunoglobulina G/metabolismo , Isotipos de Imunoglobulinas/metabolismo , Imunoglobulina M/metabolismo , Técnicas Imunológicas , Masculino , Pessoa de Meia-Idade
19.
J Neuroimmunol ; 28(3): 237-48, 1990 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-1695639

RESUMO

Antibodies to myelin components, such as myelin basic protein (MBP), may play a role in pathogenesis of multiple sclerosis (MS) but results from determinations of anti-MBP antibodies are inconsistent. Enumeration of cells secreting antibodies represents a new approach to evaluate a specific antibody response regarding extent and localization, and reduces effects of e.g. antibody binding to target. Anti-MBP IgG antibody secreting cells were present in MS patients' cerebrospinal fluid (CSF) at a mean value of 1 per 833 cells, and they amounted to a mean value of about 2454 in the whole CSF compartment. Similar numbers were encountered in patients with other inflammatory neurological diseases (OIND). During follow-up, anti-MBP IgG antibody secreting cells persisted regarding frequency and numbers in MS, but decreased in OIND. Such cells were rarely detected in patients with tension headache. No correlations to clinical exacerbation of MS, disability or duration were discernable. In blood from MS and OIND patients, anti-MBP IgG antibody secreting cells were detected infrequently and at low numbers. The anti-MBP antibody response is strongly restricted to the IgG isotype. The anti-MBP IgG antibody response which is persistent and compartmentalized to the diseased organ, may be important for the development of MS.


Assuntos
Imunoglobulina G/líquido cefalorraquidiano , Esclerose Múltipla/imunologia , Proteína Básica da Mielina/imunologia , Adulto , Idoso , Células Produtoras de Anticorpos/imunologia , Feminino , Cefaleia/imunologia , Humanos , Masculino , Meningite/imunologia , Pessoa de Meia-Idade , Esclerose Múltipla/líquido cefalorraquidiano
20.
Proc Biol Sci ; 267(1451): 1457-61, 2000 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-10983831

RESUMO

According to theory, a small diurnal bird living in a predictable environment should have the highest feeding effort as late as possible in the day in order to minimize the time it carries large and costly reserves. The feeding effort should also decline with increasing food availability. We tested both these ideas with the lesser spotted woodpecker (Dendrocopos minor). For most of the year, this bird feeds on wood-living insects in dead tree branches. This food supply is likely to be highly predictable on a daily scale. Our results corroborated the theory. We found that the proportion of time spent actively feeding was lower in the mornings (before noon) than in the afternoons. We also found that woodpeckers spent less time feeding the higher their food availability However, for a given food availability they spent more time feeding in the afternoons. This supports the idea that feeding is less and other activities are more valuable in the mornings given a predictable food resource. This is the first demonstration of daily routines in small birds concordant with a predictable environment. In spring, males but not females reduced their feeding time. This difference between the sexes may be related to their sex-specific reproductive effort.


Assuntos
Aves/fisiologia , Animais , Comportamento Alimentar , Feminino , Masculino
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