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1.
Sci Total Environ ; 616-617: 1101-1123, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29132720

RESUMO

The rapid increase of the world population constantly demands more food production from agricultural soils. This causes conflicts, since at the same time strong interest arises on novel bio-based products from agriculture, and new perspectives for rural landscapes with their valuable ecosystem services. Agriculture is in transition to fulfill these demands. In many countries, conventional farming, influenced by post-war food requirements, has largely been transformed into integrated and sustainable farming. However, since it is estimated that agricultural production systems will have to produce food for a global population that might amount to 9.1 billion by 2050 and over 10 billion by the end of the century, we will require an even smarter use of the available land, including fallow and derelict sites. One of the biggest challenges is to reverse non-sustainable management and land degradation. Innovative technologies and principles have to be applied to characterize marginal lands, explore options for remediation and re-establish productivity. With view to the heterogeneity of agricultural lands, it is more than logical to apply specific crop management and production practices according to soil conditions. Cross-fertilizing with conservation agriculture, such a novel approach will provide (1) increased resource use efficiency by producing more with less (ensuring food security), (2) improved product quality, (3) ameliorated nutritional status in food and feed products, (4) increased sustainability, (5) product traceability and (6) minimized negative environmental impacts notably on biodiversity and ecological functions. A sustainable strategy for future agriculture should concentrate on production of food and fodder, before utilizing bulk fractions for emerging bio-based products and convert residual stage products to compost, biochar and bioenergy. The present position paper discusses recent developments to indicate how to unlock the potentials of marginal land.

2.
Plant Biol (Stuttg) ; 18(3): 376-81, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26577608

RESUMO

Trans-generational adaptation is important to respond rapidly to environmental challenges and increase overall plant fitness. Besides well-known mechanisms such as epigenetic modifications, vertically transmitted endophytic bacteria might contribute to this process. The cultivable and total endophytic communities of several generations of Arabidopsis thaliana seeds harvested from plants exposed to cadmium (Cd) or not exposed were investigated. The diversity and richness of the seed endophytic community decreased with an increasing number of generations. Aeromicrobium and Pseudonocardia were identified as indicator species in seeds from Cd-exposed plants, while Rhizobium was abundantly present in both seed types. Remarkably, Rhizobium was the only genus that was consistently detected in seeds of all generations, which suggests that the phenotypic characteristics were more important as selection criteria for which bacteria are transferred to the next plant generation than the actual genera. Production of IAA was an important trait for endophytes from both seed types, while ACC deaminase activity and Cd tolerance were mainly associated with seed endophytes from Cd-exposed plants. Understanding how different factors influence the seed endophytic community can help us to improve seed quality and plant growth through different biotechnological applications.


Assuntos
Arabidopsis/microbiologia , Bactérias/isolamento & purificação , Cádmio/farmacologia , Endófitos/isolamento & purificação , Actinobacteria/classificação , Actinobacteria/isolamento & purificação , Actinobacteria/metabolismo , Arabidopsis/efeitos dos fármacos , Bactérias/classificação , Bactérias/metabolismo , Proteínas de Bactérias/metabolismo , Biodiversidade , Carbono-Carbono Liases/metabolismo , Endófitos/classificação , Endófitos/metabolismo , Fenótipo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/microbiologia , Rhizobium/classificação , Rhizobium/isolamento & purificação , Rhizobium/metabolismo , Sementes/efeitos dos fármacos , Sementes/microbiologia , Análise de Sequência de DNA
3.
Syst Appl Microbiol ; 39(1): 58-66, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26656884

RESUMO

Endophytic bacteria often have beneficial effects on their host plants that can be exploited for bioremediation applications but, according to the literature, only 0.001-1% of all endophytic microbes should be cultivable. This study compared the cultivated endophytic communities of the roots and shoots of Cucurbita pepo with the total endophytic communities as determined by cultivation-dependent techniques and 454 pyrosequencing. The ten most abundant taxa of the total communities aligned well with the cultivated taxa; however, the abundance of these taxa in the two communities differed greatly. Enterobacter showed very low presence in the total communities, whereas they were dominantly present in the cultivated communities. Although Rhizobium dominated in total root and shoot communities, it was poorly cultivable and even then only in growth media containing plant extract. Since endophytes likely contribute to plant-growth promotion, cultivated bacterial strains were tested for their plant-growth promoting capabilities, and the results were correlated with their abundance in the total community. Bacillus and Pseudomonas showed promising results when considering cultivability, abundance in the total community and plant-growth promoting capability. This study demonstrated that, although a limited number of bacterial genera were cultivable, current cultivation-dependent techniques may be sufficient for further isolation and inoculation experiments that aim to improve phytoremediation efficiency.


Assuntos
Bacillus/crescimento & desenvolvimento , Cucurbita/microbiologia , Endófitos/crescimento & desenvolvimento , Enterobacter/crescimento & desenvolvimento , Raízes de Plantas/microbiologia , Brotos de Planta/microbiologia , Pseudomonas/crescimento & desenvolvimento , Rhizobium/crescimento & desenvolvimento , Bacillus/genética , Bacillus/isolamento & purificação , Biodiversidade , DNA Bacteriano/genética , Endófitos/genética , Endófitos/isolamento & purificação , Enterobacter/genética , Enterobacter/isolamento & purificação , Tipagem Molecular , Pseudomonas/genética , Pseudomonas/isolamento & purificação , RNA Ribossômico 16S , Rhizobium/genética , Rhizobium/isolamento & purificação
4.
Plant Biol (Stuttg) ; 16(5): 988-96, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24400887

RESUMO

In order to stimulate selection for plant-associated bacteria with the potential to improve Cd phytoextraction, yellow lupine plants were grown on a metal-contaminated field soil. It was hypothesised that growing these plants on this contaminated soil, which is a source of bacteria possessing different traits to cope with Cd, could enhance colonisation of lupine with potential plant-associated bacteria that could then be inoculated in Cd-exposed plants to reduce Cd phytotoxicity and enhance Cd uptake. All cultivable bacteria from rhizosphere, root and stem were isolated and genotypically and phenotypically characterised. Many of the rhizobacteria and root endophytes produce siderophores, organic acids, indole-3-acetic acid (IAA) and aminocyclopropane-1-carboxylate (ACC) deaminase, as well as being resistant to Cd and Zn. Most of the stem endophytes could produce organic acids (73.8%) and IAA (74.3%), however, only a minor fraction (up to 0.7%) were Cd or Zn resistant or could produce siderophores or ACC deaminase. A siderophore- and ACC deaminase-producing, highly Cd-resistant Rhizobium sp. from the rhizosphere, a siderophore-, organic acid-, IAA- and ACC deaminase-producing highly Cd-resistant Pseudomonas sp. colonising the roots, a highly Cd- and Zn-resistant organic acid and IAA-producing Clavibacter sp. present in the stem, and a consortium composed of these three strains were inoculated into non-exposed and Cd-exposed yellow lupine plants. Although all selected strains possessed promising in vitro characteristics to improve Cd phytoextraction, inoculation of none of the strains (i) reduced Cd phytotoxicity nor (ii) strongly affected plant Cd uptake. This work highlights that in vitro characterisation of bacteria is not sufficient to predict the in vivo behaviour of bacteria in interaction with their host plants.


Assuntos
Cádmio/metabolismo , Lupinus/microbiologia , Poluentes do Solo/metabolismo , Actinomycetales/metabolismo , Actinomycetales/fisiologia , Biodegradação Ambiental , Lupinus/metabolismo , Pseudomonas/metabolismo , Pseudomonas/fisiologia , Rhizobium/metabolismo , Rhizobium/fisiologia , Rizosfera , Solo/química , Simbiose
5.
Neuropediatrics ; 36(4): 260-4, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16138251

RESUMO

Acute motor and sensory axonal neuropathy (AMSAN) is a recently described subtype of Guillain-Barré syndrome characterized by acute onset of distal weakness, loss of deep tendon reflexes and sensory symptoms. Electrophysiological studies show mildly reduced nerve conduction velocities combined with a marked reduction of muscle action and sensory nerve action potentials. Here, we report a 15-year-old boy who suffered from severe burning and knife-like pain that increased over a period of three months and resulted in a disrupted sleep pattern and suicidal intentions as well as marked loss of weight. In addition, he developed muscle weakness in his hands and feet. Neurophysiological and histopathological studies revealed AMSAN. Marked improvement of his condition was achieved by treatment with intravenous immunoglobulins, high-dose methylprednisolone, and a combination of gabapentin, antidepressants, and an oral morphine.


Assuntos
Síndrome de Guillain-Barré/complicações , Debilidade Muscular/etiologia , Dor/etiologia , Adolescente , Axônios/fisiologia , Antígenos CD8/metabolismo , Eletrofisiologia , Síndrome de Guillain-Barré/patologia , Receptor Celular 1 do Vírus da Hepatite A , Humanos , Imuno-Histoquímica/métodos , Masculino , Glicoproteínas de Membrana/metabolismo , Microscopia Eletrônica de Transmissão/métodos , Fibras Nervosas Mielinizadas/metabolismo , Fibras Nervosas Mielinizadas/patologia , Fibras Nervosas Mielinizadas/ultraestrutura , Condução Nervosa/fisiologia , Exame Neurológico , Receptores Virais/metabolismo , Nervo Sural/patologia , Nervo Sural/ultraestrutura
6.
Eur Respir J ; 17(2): 225-32, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11334124

RESUMO

Asthma can be effectively treated by the use of bronchodilator therapies administered by inhalation. The objective of this study was to describe the dose-response relationship of combined doses of fenoterol hydrobromide (F) and ipratropium bromide (I) (F/I) delivered via Respimat, a soft mist inhaler, and to establish the Respimat dose which is as efficacious and as safe as the standard marketed dose of F/I (100/40 microg) which is delivered via a conventional metered dose inhaler (MDI). In a double-blind (within device) cross-over study with a balanced incomplete block design, 62 patients with stable bronchial asthma (mean forced expiratory volume in one second (FEV1) 63% predicted) were randomized at five study centres to receive five out of eight possible treatments: placebo, F/I 12.5/5, 25/10, 50/20, 100/40 or 200/80 microg delivered via Respimat; F/I 50/20 or 100/40 microg delivered via MDI. Pulmonary function results were based on the per-protocol dataset, comprising 47 patients. All F/I doses produced greater increases in FEV1 than placebo. A log-linear dose-response was obtained for the average increase in FEV1 up to 6 h (AUC0-6 h) and peak FEV1 across the dose range administered by Respimat. Statistically, therapeutic equivalence was not demonstrated between any F/I dose administered by Respimat compared with the MDI. However 12.5/5 and 25/10 microg F/I administered via Respimat were closest (slightly superior) to the F/I dose of 100/40 microg delivered via MDI. Pharmacokinetic data from 34 patients indicated a two-fold greater systemic availability of both drugs following inhalation by Respimat compared to MDI. In general, the active treatments were well tolerated and safe with regard to vital signs, electrocardiography, laboratory parameters and adverse events. In conclusion, combined administration of fenoterol hydrobromide and ipratropium bromide via Respimat, is as effective and as safe as higher doses given via a metered dose inhaler.


Assuntos
Asma/tratamento farmacológico , Broncodilatadores/administração & dosagem , Fenoterol/administração & dosagem , Ipratrópio/administração & dosagem , Nebulizadores e Vaporizadores , Administração por Inalação , Adulto , Asma/fisiopatologia , Broncodilatadores/farmacocinética , Estudos Cross-Over , Relação Dose-Resposta a Droga , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Fenoterol/farmacocinética , Volume Expiratório Forçado , Humanos , Ipratrópio/farmacocinética , Masculino , Capacidade Vital
7.
Respiration ; 67(3): 306-14, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10867600

RESUMO

BACKGROUND: Respimat, a possible alternative to the conventional metered dose inhaler (MDI), is a novel, reusable, propellant-free, multidose soft mist inhaler. Respimat slowly releases a metered dose of active substance as a soft mist with a high proportion of the dose in the fine particle fraction, leading to improved lung deposition following inhalation when compared with the conventional MDI. OBJECTIVES AND METHODS: The equipotent bronchodilating efficacy and safety of a combination of fenoterol hydrobromide and ipratropium bromide (F/I) in cumulative doses delivered by either Respimat or pressurised MDI was assessed in a randomised, controlled, double-blind (within device) 4-way crossover study. Forty-three patients with stable asthma (mean FEV(1) 62% predicted) responsive to F/I inhaled cumulatively 16 puffs on each of 4 test days (1 + 1 + 2 + 4 + 8 puffs at 50-min intervals) via Respimat delivering 50/20, 25/20 or 25/10 microg F/I per puff or via MDI delivering 50/20 microg F/I per puff. RESULTS: Cumulative doses of 400/160 and 400/320 microg F/I via Respimat produced bronchodilation (evaluated by average increase in FEV(1) 45-245 min after first inhalation) equivalent to that achieved with a cumulative 800/320 microg F/I via MDI (mean increase in FEV(1) above baseline 0.76, 0.73 and 0.71 litres, respectively). The tolerability of the F/I combination via Respimat was also comparable to that of twice the dose delivered via MDI. CONCLUSION: Therefore, a fenoterol hydrobromide/ipratropium bromide combination delivered by Respimat is as safe and effective as the MDI at half the cumulative dose, on acute administration to patients with asthma.


Assuntos
Asma/tratamento farmacológico , Broncodilatadores/administração & dosagem , Fenoterol/administração & dosagem , Ipratrópio/administração & dosagem , Nebulizadores e Vaporizadores , Administração por Inalação , Adolescente , Adulto , Idoso , Análise de Variância , Asma/diagnóstico , Estudos Cross-Over , Relação Dose-Resposta a Droga , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Testes de Função Respiratória , Índice de Gravidade de Doença , Resultado do Tratamento
11.
Infection ; 21(1): 71-4, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8449588

RESUMO

In order to establish guidelines for the dosage of teicoplanin, a new glycopeptide antibiotic, in patients with end stage renal failure, 40 cases of suspected or proven gram-positive infections were treated with teicoplanin. Three different dosage regimens were used and peak/trough serum levels measured. Thirty-one patients were cured and six patients died. Teicoplanin was well tolerated. For severe cases of septicemia with staphylococci in patients undergoing hemodialysis a teicoplanin therapy consisting of 800 mg on day 1 followed by administrations of 400 mg on days 2, 3, 5, 12, and 19 is recommended. Minor infections are treated initially with 800 mg followed by administration of 400 mg at weekly intervals.


Assuntos
Infecções por Bactérias Gram-Positivas/metabolismo , Diálise Renal , Teicoplanina/farmacocinética , Adulto , Idoso , Idoso de 80 Anos ou mais , Bacteriemia/tratamento farmacológico , Bacteriemia/microbiologia , Esquema de Medicação , Infecções por Bactérias Gram-Positivas/tratamento farmacológico , Humanos , Falência Renal Crônica/complicações , Falência Renal Crônica/metabolismo , Pessoa de Meia-Idade , Teicoplanina/administração & dosagem , Teicoplanina/uso terapêutico
12.
J Biolumin Chemilumin ; 1(2): 47-51, 1986 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-3505413

RESUMO

The amount of adenosine triphosphate (ATP) in human lymphocytes was determined using a technique based on light emission from a bioluminescent reaction with luciferin-luciferase. The amount of ATP changed when cells were incubated in the presence of specific HLA antisera and complement. For determination of intracellular ATP a modified method was applied, which was based on reduction of extracellular ATP by the addition of ATPase. The results of titration of an anti-human lymphocyte serum using the bioluminescence assay were in agreement with the results of fluorescence vitality staining. Bioluminescent HLA-determination in 57 cell samples each tested with 5 different antisera also gave good agreement (95.8%) with the conventional method. From these experimental data the calculated ATP content per lymphocyte was 0.135 +/- 0.058 pg ATP.


Assuntos
Trifosfato de Adenosina/análise , Antígenos HLA/análise , Teste de Histocompatibilidade/métodos , Linfócitos/imunologia , Luciferina de Vaga-Lumes , Humanos , Luciferases , Medições Luminescentes , Linfócitos/análise
13.
Psychiatr Prax ; 13(1): 24-31, 1986 Jan.
Artigo em Alemão | MEDLINE | ID: mdl-3961027

RESUMO

In Limburg, Netherlands, a project is going on aiming to implement lower class-linked skill-therapies into the regional mental health services. This article elucidates: the poor relationship that exists between contemporary psychotherapy and the lower class clients; various efforts that have been attempted to solve this problem; the basic elements of Goldstein's 'structured learning therapy'; activities and results of the Dutch 'Goldsteinproject'.


Assuntos
Terapia Comportamental/métodos , Transtornos Mentais/terapia , Carência Psicossocial , Assertividade , Humanos , Comportamento Imitativo , Relações Interpessoais , Países Baixos , Desempenho de Papéis , Ajustamento Social , Meio Social
14.
Eur J Clin Microbiol ; 4(6): 556-61, 1985 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-3937733

RESUMO

The antimicrobial susceptibility of Mycobacterium tuberculosis H37Rv and 17 clinical isolates of the same species was determined using a bioluminescence assay to measure adenosine triphosphate (ATP) produced by bacteria in the broth dilution test performed in Dubos-Tween-albumin broth. The results were compared with those obtained with the standard dilution proportional method performed on Löwenstein-Jensen medium. The drugs tested were streptomycin, rifampin, ethambutol and isoniazid. There was high correlation between bacterial count and ATP concentration in a liquid culture of Mycobacterium tuberculosis H37Rv (r = 0.993); when several cultures of the same strain were assayed after different incubation periods the correlation was somewhat lower (r = 0.846). Addition of tuberculostatic drugs in inhibitory concentrations resulted in a reduction in the ATP concentration as compared to control assays without drugs. Results of susceptibility tests performed by the two methods agreed in 66 out of 68 assays. Differences in the inhibitory concentrations determined by the two methods were due to differences in the methods. Whereas the standard method requires 3 to 4 weeks of incubation, results of the bioluminescence assay were available after five days of incubation. Automation of the assay for routine use is possible.


Assuntos
Trifosfato de Adenosina/análise , Antituberculosos/farmacologia , Mycobacterium tuberculosis/efeitos dos fármacos , Resistência Microbiana a Medicamentos , Etambutol/farmacologia , Imunofluorescência , Isoniazida/farmacologia , Medições Luminescentes , Testes de Sensibilidade Microbiana , Rifampina/farmacologia , Estreptomicina/farmacologia
15.
Zentralbl Bakteriol Mikrobiol Hyg A ; 258(4): 464-71, 1984 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-6398568

RESUMO

A bioluminescence assay for the rapid detection of bacteria in blood culture bottles was developed and the results compared with the findings of microscopic examination. For this purpose 50 culture bottles supplemented with blood were inoculated with bacteria. After 4, 6 and 7 h of incubation at 37 degrees C samples were removed and examined microscopically and with bioluminescence technique measuring bacterial ATP in whole blood. Colony counts were performed at each interval. The limit of detection in bioluminescence assays was reached at a bacterial density of 1 X 10(5) CFU/ml (p less than 0.001) using Escherichia coli ATCC 25923 and Staphylococcus aureus ATCC 25922. At the ame time 19 out of 20 microscopic examinations were positive. The results indicate that the bioluminescence technique has an equal sensitivity in detecting bacterial growth in blood culture bottles as the microscopic examination using stained smears. The bioluminescence technique has the potential of automation.


Assuntos
Bactérias/isolamento & purificação , Técnicas Bacteriológicas , Sepse/diagnóstico , Escherichia coli/isolamento & purificação , Humanos , Medições Luminescentes , Staphylococcus aureus/isolamento & purificação
19.
Artigo em Inglês | MEDLINE | ID: mdl-6372329

RESUMO

Results of a comparative study for the detection of significant bacteriuria (greater than 10(5)/ml) under routine conditions in 300 urine samples were reported. The urine specimens were obtained from patients of different clinical departments of our university hospital. Only midstream urines were investigated. The results from ATP determination with bioluminescence, quantitative determination of colony forming units and a semiquantitative method with standard loop were compared. The obtained data with different methods show a good correlation. Only four cases (1.3 per cent) were classified false negative and 10 urines (3.3 per cent) false positive with the bioluminescence method. In contrast to the conventional methods the results from bioluminescence assay can be obtained within 30 min.


Assuntos
Técnicas Bacteriológicas , Bacteriúria/diagnóstico , Ágar , Luciferina de Vaga-Lumes , Humanos , Luciferases , Medições Luminescentes
20.
Med Microbiol Immunol ; 172(2): 117-22, 1983.
Artigo em Inglês | MEDLINE | ID: mdl-6350833

RESUMO

Bacterial adenosine triphosphate (ATP) was determined in blood culture bottles using bioluminescence. Seventy bottles were inoculated with blood and bacteria. Immediately after inoculation and every 2 h thereafter for the next 10 h, bacterial ATP was measured as well as the number of colony-forming units (CFU) per millilitre of blood culture bottle. The curves for the concentration of CFUs and for the amount of bacterial ATP present are quite similar and indicate that the method described promises good results in the early detection of bacteria in blood culture bottles. ATP values greater than 0.1 ng/ml blood culture bottle indicate bacterial growth. This limit of detection is reached at a concentration of 4-6 X 10(4) CFU/ml of the Escherichia coli ATCC 11229 strain tested.


Assuntos
Trifosfato de Adenosina/sangue , Infecções por Escherichia coli/diagnóstico , Sepse/diagnóstico , Bioensaio , Escherichia coli/crescimento & desenvolvimento , Escherichia coli/metabolismo , Luciferina de Vaga-Lumes/metabolismo , Humanos , Luciferases/metabolismo , Medições Luminescentes
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