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1.
Appl Environ Microbiol ; 87(23): e0106021, 2021 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-34550767

RESUMO

Campylobacter from contaminated poultry meat is a major source of human gastroenteritis worldwide. To date, attempts to control this zoonotic infection with on-farm biosecurity measures have been inconsistent in outcome. A cornerstone of these efforts has been the detection of chicken infection with microbiological culture, where Campylobacter is generally not detectable until birds are at least 21 days old. Using parallel sequence-based bacterial 16S profiling analysis and targeted sequencing of the porA gene, Campylobacter was identified at very low levels in all commercial flocks at less than 8 days old that were tested from the United Kingdom, Switzerland, and France. These young chicks exhibited a much greater diversity of porA types than older birds testing positive for Campylobacter by culture or quantitative PCR (qPCR). This suggests that as the bacteria multiply sufficiently to be detected by culture methods, one or two variants, as indicated by porA type, dominate the infection. The findings that (i) most young chicks carry some Campylobacter and (ii) not all flocks become Campylobacter positive by culture suggest that efforts to control infection, and therefore avoid contamination of poultry meat, should concentrate on how to limit Campylobacter to low levels by the prevention of the overgrowth of single strains. IMPORTANCE Our results demonstrate the presence of Campylobacter DNA among fecal samples from a range of commercially reared meat chicks that are less than 8 days of age, consistent across 3 European countries. The recently developed, sensitive detection method indicates that infection occurs on commercial farms much earlier and more widely than previously thought, which opens up new opportunities to control Campylobacter contamination at the start of the food chain and reduce the unacceptably high levels of human disease.


Assuntos
Infecções por Campylobacter/veterinária , Campylobacter , Galinhas , Animais , Campylobacter/genética , Campylobacter/isolamento & purificação , Galinhas/microbiologia , DNA Bacteriano/genética , França , RNA Ribossômico 16S/genética , Suíça , Reino Unido
2.
J Cell Biol ; 150(1): 165-76, 2000 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-10893265

RESUMO

Neurofilaments are transported through axons by slow axonal transport. Abnormal accumulations of neurofilaments are seen in several neurodegenerative diseases, and this suggests that neurofilament transport is defective. Excitotoxic mechanisms involving glutamate are believed to be part of the pathogenic process in some neurodegenerative diseases, but there is currently little evidence to link glutamate with neurofilament transport. We have used a novel technique involving transfection of the green fluorescent protein-tagged neurofilament middle chain to measure neurofilament transport in cultured neurons. Treatment of the cells with glutamate induces a slowing of neurofilament transport. Phosphorylation of the side-arm domains of neurofilaments has been associated with a slowing of neurofilament transport, and we show that glutamate causes increased phosphorylation of these domains in cell bodies. We also show that glutamate activates members of the mitogen-activated protein kinase family, and that these kinases will phosphorylate neurofilament side-arm domains. These results provide a molecular framework to link glutamate excitotoxicity with neurofilament accumulation seen in some neurodegenerative diseases.


Assuntos
Transporte Axonal/fisiologia , Ácido Glutâmico/metabolismo , Proteínas de Neurofilamentos/metabolismo , Neurônios/enzimologia , Transporte Axonal/efeitos dos fármacos , Transporte Biológico Ativo/efeitos dos fármacos , Células Cultivadas , Ácido Glutâmico/farmacologia , Proteínas de Fluorescência Verde , Humanos , Proteínas Luminescentes/genética , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Neuritos/metabolismo , Proteínas de Neurofilamentos/genética , Neurônios/citologia , Fosforilação/efeitos dos fármacos , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Transfecção
3.
Br J Radiol ; 57(675): 241-5, 1984 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-6697085

RESUMO

Radiation treatment fields have been established in 40 patients with carcinoma of the urinary bladder using a technique based on B-scan measurements of tumour dimensions and position. Three-dimensional data were obtained using omnidirectional calipers and the in-built measuring system of the scanner gantry, and by measurement from the recorded images. All measurements of the tumour dimensions and co-ordinates of the tumour centre were related to a fixed patient reference point. The ultrasound measurements were superimposed on to the AP and lateral planning radiographs after multiplication by the appropriate magnification factor. Ultrasound tomograms provided accurate data for radiotherapy planning and offer a convenient method for monitoring the response to treatment on follow-up.


Assuntos
Ultrassonografia , Neoplasias da Bexiga Urinária/diagnóstico , Humanos , Radiografia , Bexiga Urinária/diagnóstico por imagem , Neoplasias da Bexiga Urinária/diagnóstico por imagem , Neoplasias da Bexiga Urinária/radioterapia
4.
Curr Alzheimer Res ; 6(3): 269-78, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19519308

RESUMO

Collapsin response mediator protein-2 (CRMP2) was recently identified as a physiological substrate for GSK3 and Cdk5, two protein kinases suggested to exhibit greater activity in Alzheimer's disease (AD). Indeed, phosphorylation of CRMP2, at the residues targeted by GSK3 and Cdk5, is relatively high in cortex isolated from human AD brain, as well as in the brains of animal models of AD, while phospho-CRMP2 is found in neurofibrillary tangles. In mouse models of AD, increased phosphorylation occurs prior to pathology. Although CRMP2 has no known enzymatic activity, a great deal of information is appearing on its importance in neuronal development and polarity, as well as in axon growth and guidance. In this mini-review, we examine what is known about CRMP2 function, how that is controlled by phosphorylation, what alterations in molecular mechanisms could lead to the abnormally high CRMP2 phosphorylation in AD, and whether this is likely to be specific to AD or occur in other forms of neurodegeneration. This will include discussion of the evidence for increased GSK3 or Cdk5 activity, for decreased phosphatase activity, or the upregulation of other CRMP2 protein kinases in AD. Importantly, we will compare the processes that may contribute to increased CRMP2 phosphorylation with those known to increase tau hyperphosphorylation in AD, and whether these are likely to be part of disease development or a useful early marker for AD.


Assuntos
Doença de Alzheimer/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Doença de Alzheimer/diagnóstico , Animais , Quinase 5 Dependente de Ciclina/metabolismo , Progressão da Doença , Regulação da Expressão Gênica/fisiologia , Quinase 3 da Glicogênio Sintase/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/genética , Proteínas do Tecido Nervoso/genética , Fosforilação/fisiologia
5.
Radiography ; 53(610): 161-3, 1987.
Artigo em Inglês | MEDLINE | ID: mdl-3671699

RESUMO

In this paper the author aims to instigate discussion on the manner in which we, as a profession, currently approach and perform quality assurance. To what use we put the results and the way in which quality assurance should progress in the future. It is based mainly on his experience as radiographic service manager of an eight-roomed x-ray department with responsibility for the radiographic services for one of the centres of the DHSS breast cancer early detection project.


Assuntos
Garantia da Qualidade dos Cuidados de Saúde/tendências , Radiografia/normas , Inglaterra , Falha de Equipamento , Humanos , Controle de Qualidade , Radiografia/instrumentação
6.
Appl Environ Microbiol ; 47(6): 1250-4, 1984 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16346562

RESUMO

A simple gas-liquid chromatographic procedure for analyzing ethanol, acetic acid, acetoin, and racemic and meso-2,3-butylene glycol in broth media is described. Overnight broth cultures were filtered or centrifuged, and the filtrate or supernatant was treated with formic acid to aid separation of volatile fatty acids. Samples were then directly analyzed by gas-liquid chromatography on a 20% Tween 80-Chromosorb W-AW column and propionic acid as an internal standard. A complete analysis took ca. 8 min. The method can be used to distinguish homofermentative from heterofermentative lactic acid bacteria based on the level of ethanol produced and citrate-utilizing from non-citrate-utilizing lactic acid bacteria based on the levels of acetic acid produced. The method also has potential in distinguishing other bacterial fermentations. Of the 13 species of lactic acid bacteria tested, Streptococcus lactis subsp. diacetylactis was the major producer of 2,3-butylene glycol (total range, 0.3 to 3.5 mM), and, except for strain DRC1, both the racemic and meso isomers were produced in approximately equal amounts.

7.
Cell Mol Life Sci ; 59(2): 323-30, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11924605

RESUMO

Neurofilaments are among the most abundant organelles in neurones. They are synthesised in cell bodies and then transported into and through axons by a process termed 'slow axonal transport' at a rate that is distinct from that driven by conventional fast motors. Several recent studies have now demonstrated that this slow rate of transport is actually the consequence of conventional fast rates of movement that are interrupted by extended pausing. At any one time, most neurofilaments are thus stationary. Accumulations of neurofilaments are a pathological feature of several human neurodegenerative diseases suggesting that neurofilament transport is disrupted in disease states. Here, we review recent advances in our understanding of neurofilament transport in both normal and disease states. Increasing evidence suggests that phosphorylation of neurofilaments is a mechanism for regulating their transport properties, possibly by promoting their detachment from the motor(s). In some neurodegenerative diseases, signal transduction mechanisms involving neurofilament kinases and phosphatases may be perturbed leading to disruption of transport.


Assuntos
Transporte Axonal , Filamentos Intermediários/metabolismo , Doenças Neurodegenerativas/metabolismo , Humanos , Neurônios/metabolismo , Neurônios/ultraestrutura , Fosforilação
8.
Toxicol Ind Health ; 7(4): 277-94, 1991 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-1776158

RESUMO

An extended follow-up from 1977-84 was achieved in a cohort of 11,567 nickel workers engaged in mining, milling and smelting originally studied from 1950-76. Exposure data were incorporated into the analysis. One nasal cancer occurred. The lung cancer Standardized Mortality Ratio beyond 15 years from first exposure was significantly high overall (128) and in miners (153). However, detailed analyses by era of first mining and duration of mining, as well as cumulative exposure to different nickel species, did not appear consistent with an occupational etiology since significant trends were not observed. At the levels of exposure incurred, large increases in lung and nasal cancer, observed in nickel refineries elsewhere, did not occur.


Assuntos
Níquel/efeitos adversos , Doenças Profissionais/mortalidade , Monitoramento Ambiental , Seguimentos , Humanos , Masculino , Metalurgia , Mineração , Doenças Profissionais/induzido quimicamente
9.
Carcinogenesis ; 8(2): 305-13, 1987 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-3802416

RESUMO

Ten nickel oxides and nickel-copper oxides, which all contained NiO (bunsenite) as the predominant crystalline phase, were assayed as follows: in vitro dissolution tests in water and body fluids; in vitro phagocytosis tests in Chinese hamster ovary and C3H-10T1/2 cells; morphological transformation and cytotoxicity tests in cultured Syrian hamster embryo (SHE) cells; erythropoiesis stimulation assay by intrarenal administration to Fischer-344 rats; and scoring the renal histopathologic responses in rats killed 3 months post-injection. The test compounds differed substantially in their biological effects when tested in the various experimental systems. Based upon highly significant concordance of ranked results in the assays (P less than 0.001), six colligative biological attributes of the compounds were identified: (i) dissolution half-times in rat serum and renal cytosol; (ii) phagocytosis by C3H-10T1/2 cells; (iii) morphological transformation of SHE cells; (iv) erythropoiesis stimulation in rats; (v) induction of tubular hyperplasia in rat kidneys; and (vi) induction of arteriosclerosis in rat kidneys. Strong rank correlation (P less than 0.01) between results of the cell transformation and erythropoiesis stimulation assays is especially notable, since the compounds were tested by blind protocols in independent laboratories. The presence of high surface area and demonstrable Ni(III) were two physicochemical characteristics that were associated with the greatest biological effects of nickel oxides.


Assuntos
Níquel , Animais , Sobrevivência Celular/efeitos dos fármacos , Transformação Celular Neoplásica/efeitos dos fármacos , Células Cultivadas , Fenômenos Químicos , Físico-Química , Cricetinae , Eritropoese/efeitos dos fármacos , Nefropatias/induzido quimicamente , Nefropatias/patologia , Camundongos , Níquel/toxicidade , Fagocitose , Ratos , Solubilidade , Relação Estrutura-Atividade
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