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1.
Opt Express ; 28(10): 14374-14385, 2020 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-32403478

RESUMO

An onboard LIght Detection And Ranging (LIDAR) sensor designed to track wake vortex created by aircraft in formation flight is presented. It uses short pulses (75 ns) to obtain a spatial resolution of ∼22.5 m required to resolve small-scale structures of vortices and a blind zone of 17.5 m to locate vortices next to the wing tip. Monte Carlo simulations show that vortex centers could be located within ±0.5 m. Flight tests were performed with two aircraft in formation flight configuration. The LIDAR, installed in the following aircraft, was able to measure, in real time (every 6 s), the air flow velocities induced by the vortices created by the leading aircraft. The software was used to determine the vortex centers. These measurements were coupled to global positioning system (GPS) measurements of the two aircraft positions to determine the falling velocity of the vortices and infer their circulations.

2.
Sci Total Environ ; 616-617: 397-407, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29127793

RESUMO

Plants and insects depend on climatic factors (temperature, solar radiation, precipitations, relative humidity and CO2) for their development. Current knowledge suggests that climate change can alter plants and insects development and affect their interactions. Shifts in tritrophic relations are of particular concern for Integrated Pest Management (IPM), because responses at the highest trophic level (natural enemies) are highly sensitive to warmer temperature. It is expected that natural enemies could benefit from better conditions for their development in northern latitudes and IPM could be facilitated by a longer period of overlap. This may not be the case in southern latitudes, where climate could become too warm. Adapting IPM to future climatic conditions requires therefore understanding of changes that occur at the various levels and their linkages. The aim of this review is to assess the current state of knowledge and highlights the gaps in the existing literature concerning how climate change can affect tritrophic relations. Because of the economic importance of wine production, the interactions between grapevine, Vitis vinifera (1st), Lobesia botrana (2nd) and Trichogramma spp., (3rd), an egg parasitoid of Lobesia botrana, are considered as a case study for addressing specific issues. In addition, we discuss models that could be applied in order quantify alterations in the synchrony or asynchrony patterns but also the shifts in the timing and spatial distribution of hosts, pests and their natural enemies.


Assuntos
Mudança Climática , Controle de Pragas , Animais , Dióxido de Carbono/análise , Herbivoria , Umidade , Himenópteros/fisiologia , Insetos , Lepidópteros/parasitologia , Temperatura , Vitis
3.
Horm Metab Res ; 46(11): 810-3, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24627097

RESUMO

We sought to investigate the impact of dialysis on glucose profiles of diabetic patients using continuous glucose monitoring (CGM). The study included 33 hemodialyzed patients with diabetes (14 females and 19 males; mean age: 66±8 years; patients with type 2 diabetes: 30; mean duration of dialysis: 3.8±2.6 years) who were under insulin treatment. After a run-in period, CGM was performed for 48 h, including a dialysis session. Three CGM sessions were proposed for each patient over a 3-month period. CGM results were analyzed during and after dialysis at 6 different time points. Moreover, data were analyzed in 7 different day periods according to meals. Of the 99 CGM available, 21 were excluded because of technical issues or patient refusal. The CGM results indicated that mean glucose values (7.5±2.5 mmol/l vs. 9.4±1.9 mmol/l; p<0.001) and variability indices (p<0.001) were lower, whereas the frequency of hypoglycemia (4.4±9.6% vs. 2.1±7.9%; p<0.001) was higher during hemodialysis sessions. Significant differences were observed in glucose values only before and 2 h after breakfast (p<0.001). Compared with other day periods, glucose values were lower during the second half of the night and higher before and after dinner (p<0.001). In summary, CGM allows the identification of a particular glucose profile in hemodialyzed diabetic patients. CGM seems feasible and clinically useful for the analysis of glucose profiles in this group of patients.


Assuntos
Automonitorização da Glicemia/métodos , Glicemia/metabolismo , Diabetes Mellitus Tipo 2/sangue , Diálise Renal , Idoso , Feminino , Humanos , Masculino
5.
Rev Med Interne ; 30(7): 628-9, 2009 Jul.
Artigo em Francês | MEDLINE | ID: mdl-18930567

RESUMO

The association of sarcoidosis and auto-immune thyroid disease has been reported. We report a 29-year-old woman, treated for hypothyroidism caused by thyrotropin-receptor blocking antibodies, who developed a sarcoidosis (Löfgren's syndrome). Auto-immune thyroid diseases and sarcoidosis could share common pathogenic mechanisms.


Assuntos
Autoanticorpos/sangue , Hipotireoidismo/imunologia , Receptores da Tireotropina/imunologia , Sarcoidose/diagnóstico , Sarcoidose/imunologia , Adulto , Feminino , Humanos
6.
Ann Chir ; 131(3): 203-10, 2006 Mar.
Artigo em Francês | MEDLINE | ID: mdl-16434021

RESUMO

BACKGROUND: Due to the relatively small number of patients involved, there is currently no consensus on what operation should be performed in patients with tertiary hyperparathyroidism after renal transplantation. METHOD: Retrospective analysis of the 70 patients with tertiary hyperparathyroidism who all underwent subtotal parathyroidectomy with transcervical thymectomy in the same institution between 1978 and 2003. RESULTS: The delay between transplantation and parathyroidectomy was 4,1+/-4,3 years. Follow up was available for all patients. Mean follow-up was 5,6+/-5 years. Glomerular filtration rate (GFR) was 53+/-21 ml/min at parathyroidectomy and 42+/-29 ml/min at follow-up [<30 ml/min in 26 patients (37%), 30 - 60 ml/min in 25 patients (36%) et>60 ml/min in 19 patients (27%)]. One patient was successfully reoperated for persistent tertiary hyperparathyroidism during follow-up. No patient was hypercalcemic at follow-up. Four patients with a GFR<30 ml/min had a PTH level>fourfold normal values (6%) without signs or symptoms of hyperparathyroidism. One patient was hypocalcemic (1,5%) and two patients were normocalcemic with undetectable or infranormal PTH level (3%) under oral vitamin D and calcium medication. CONCLUSION: This approach permits not only to cure the majority of patients with tertiary hyperparathyroidism but also to avoid recurrence when the renal function declines. When medical management has failed, we recommend systematic subtotal parathyroidectomy with thymectomy for patients with tertiary hyperparathyroidism and this should usually be performed during the second year after transplantation.


Assuntos
Hiperparatireoidismo/cirurgia , Transplante de Rim/efeitos adversos , Paratireoidectomia/métodos , Timectomia/métodos , Adulto , Feminino , Humanos , Hiperparatireoidismo/etiologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento
8.
Scand J Rheumatol ; 34(5): 399-403, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16234190

RESUMO

Adult Still's disease (ASD) is a rare systemic disorder characterized by fever, arthralgia, cutaneous rash, and lymphadenopathy, with high polymorphonuclear leucocytosis and low glycosylated ferritinaemia. Kidney involvement has been reported rarely. We present a patient with ASD who developed haemolytic uraemic syndrome (HUS). The 42-year-old patient was admitted for unexplained fever related to ASD according to Yamaguchi's classification criteria. As Still's disease was resistant to prednisone, high-dose intravenous immunoglobulins (IV Ig) were administered. During the follow-up the patient developed acute renal failure and non-immune haemolytic anaemia with high levels of antiphospholipid antibodies (IgG anticardiolipin antibodies and anti-beta2 glycoprotein 1 antibodies). Renal biopsy disclosed thrombotic microangiopathy (TMA) with arteriolar and glomerular involvement. Treatment with steroids and intravenous IV Ig was reinitiated but renal function worsened towards end-stage renal failure. In this case, we suggest that antiphospholipid antibodies could have promoted arteriolar and glomerular TMA. HUS may be the cause of acute renal failure in Still's disease.


Assuntos
Injúria Renal Aguda/etiologia , Síndrome Hemolítico-Urêmica/etiologia , Doença de Still de Início Tardio/complicações , Trombose/etiologia , Injúria Renal Aguda/imunologia , Adulto , Anticorpos Antifosfolipídeos/imunologia , Síndrome Hemolítico-Urêmica/imunologia , Humanos , Imunoglobulinas Intravenosas , Masculino , Microcirculação , Circulação Renal , Esteroides/uso terapêutico , Doença de Still de Início Tardio/tratamento farmacológico , Doença de Still de Início Tardio/imunologia , Trombose/imunologia
9.
Rev Med Interne ; 26(4): 288-93, 2005 Apr.
Artigo em Francês | MEDLINE | ID: mdl-15820564

RESUMO

PURPOSE: To describe the clinical and radiographic features of patients with primary localized amyloidosis of the urinary tract. METHODS: We report a case of localized amyloidosis of the ureters and bladder. The medical records of four other cases from the French Register of localized amyloidosis were reviewed. RESULTS: The mean age of three men and two women was 53 years. All patients presented with gross hematuria, four patients presented with renal colic, only one patient had irritative lower urinary tract symptoms. Ureter and bladder were involved in three patients, both ureters in two patients and the bladder only, in one patient. Clinical and radiographic presentations mimicked a neoplasia excluded by histologic analysis. Immunohistochemical study was performed in only two cases and revealed lambda light chain amyloidosis. The median follow-up was eight years. Various treatments were performed, and recurrences occurred in two cases. None of the five patients developed monoclonal gammapathy or systemic amyloidosis. CONCLUSION: Primary localized amyloidosis of the urinary tract is a rare disorder and can easily be confused with a neoplasm. The physiopathology is unknown, the prognosis is usually good. There is no specific treatment, and repeated work-up for systemic amyloidosis is unnecessary as local recurrences appear to be the main complication.


Assuntos
Amiloidose/diagnóstico , Doenças Ureterais/diagnóstico , Doenças da Bexiga Urinária/diagnóstico , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
10.
Clin Nephrol ; 59(4): 297-300, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12708571

RESUMO

The authors report about a patient who presented with acute respiratory failure, bilateral alveolar infiltrates, without signs of fluid overload, and acute renal failure. Percutaneous renal biopsy revealed acute interstitial nephritis with medulla hemorrhages. Serologic tests for Puumala virus infection were positive. Hemorrhagic fever with renal syndrome should be considered when patients present with pulmonary-renal syndrome.


Assuntos
Febre Hemorrágica com Síndrome Renal/complicações , Nefropatias/etiologia , Pneumopatias/etiologia , Virus Puumala/patogenicidade , Adulto , França , Febre Hemorrágica com Síndrome Renal/diagnóstico por imagem , Febre Hemorrágica com Síndrome Renal/virologia , Humanos , Nefropatias/diagnóstico por imagem , Nefropatias/virologia , Pneumopatias/diagnóstico por imagem , Pneumopatias/virologia , Masculino , Virus Puumala/isolamento & purificação , Radiografia , Síndrome
11.
Nephrologie ; 22(6): 301-5, 2001.
Artigo em Francês | MEDLINE | ID: mdl-11715607

RESUMO

Puumala hantavirus is the most common hantavirus infection in Western Europe. The causative agent, Puumala virus, is a member of the Hantavirus genus in the Bunyaviridae family. The natural hosts of hantaviruses are chronically, but asymptomatic infected rodents, which transmit the virus to human in their excretions. Puumala virus is carried by the bank vole, clethrionomys glareolus. Hemorrhagic fever with renal syndrome (HFRS) caused by Puumala virus in France or Belgium is very similar to the previously described Nephropathia epidemica in Scandinavia. In most severe cases, the disease is clinically characterized by high fever of abrupt onset, headache, loin or abdominal pains, nausea and vomiting, and occasionally acute and transient myopia. Renal involvement results in transient proteinuria and hematuria and acute renal failure. Except for interstitial hemorrhage in the outer medulla, the renal histopathologic findings are unspecific and include prominent changes in the interstitium with interstitial oedema and inflammatory infiltrates. Thrombocytopenia, mild elevation of liver enzymes, and leukocytosis are typical laboratory findings. Spontaneous complete recovery is the rule. Laboratory diagnosis is primarily based on serology such as indirect immunofluorescence or capture enzyme--linked immunosorbent assays which detect IgM antibodies and an increased level of IgG antibodies against Puumala virus. Viral antigen may be demonstrated in the cytoplasm of renal tubular epithelial cells.


Assuntos
Febre Hemorrágica com Síndrome Renal/virologia , Virus Puumala/patogenicidade , Injúria Renal Aguda/etiologia , Animais , Anticorpos Antivirais/sangue , Ásia/epidemiologia , Bélgica/epidemiologia , Progressão da Doença , Vetores de Doenças , França/epidemiologia , Orthohantavírus/classificação , Orthohantavírus/isolamento & purificação , Orthohantavírus/patogenicidade , Febre Hemorrágica com Síndrome Renal/complicações , Febre Hemorrágica com Síndrome Renal/diagnóstico , Febre Hemorrágica com Síndrome Renal/epidemiologia , Febre Hemorrágica com Síndrome Renal/imunologia , Febre Hemorrágica com Síndrome Renal/transmissão , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Túbulos Renais/virologia , Pneumonia Viral/etiologia , Virus Puumala/imunologia , Virus Puumala/isolamento & purificação , Roedores/virologia , Países Escandinavos e Nórdicos/epidemiologia , Estudos Soroepidemiológicos , Zoonoses
13.
Accid Anal Prev ; 33(2): 267-76, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11204898

RESUMO

The concept of prototypical accident scenario has been used since the late 1980s in French road safety research. A prototypical scenario can be defined as a prototype of the accident process corresponding to a series of accidents which are similar in terms of the chain of facts and causal relationships found throughout the various accident stages. This concept provides a means of combining and generalising the knowledge obtained from accident case studies, based on in-depth investigation methods or on detailed analyses of police reports. Applications of this concept are developed in both the field of traffic accident research and safety studies (diagnoses) in preparation for engineering measures or local safety policies. This paper presents the prototypical scenario concept, its theoretical background, and the way it is used for safety research and studies.


Assuntos
Acidentes de Trânsito/prevenção & controle , Modelos Teóricos , Acidentes de Trânsito/classificação , Coleta de Dados/métodos , França , Humanos , Pesquisa
14.
J Struct Biol ; 131(2): 156-8, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11042086

RESUMO

Crystals of a complex formed between the alpha/beta-tubulin heterodimer and SCG10, a neuron-specific growth-associated protein, have been obtained by the hanging drop method. They belong to the space group P2(1)2(1)2(1), with unit cell parameters a = 56 A, b = 353 A, c = 466 A and four molecular complexes in the asymmetric unit. A complete X-ray diffraction data set to 6.1 A resolution has been collected using synchrotron radiation. This represents a challenging opportunity to study at a molecular level the structure-function relationships between a microtubule-destabilizing protein, SCG10, and tubulin.


Assuntos
Fatores de Crescimento Neural/química , Fatores de Crescimento Neural/metabolismo , Tubulina (Proteína)/química , Tubulina (Proteína)/metabolismo , Animais , Encéfalo/metabolismo , Bovinos , Cristalização , Dimerização , Substâncias Macromoleculares , Proteínas do Tecido Nervoso/química , Proteínas do Tecido Nervoso/metabolismo , Ligação Proteica , Estrutura Quaternária de Proteína , Difração de Raios X
15.
Acta Crystallogr D Biol Crystallogr ; 56(Pt 8): 1067-9, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10944356

RESUMO

The haemagglutinin HA is a trimer of identical subunits and is the more abundant viral surface glycoprotein of the influenza virus. It is the target of antibodies that neutralize viral infectivity. Antibodies that bind to HA with 3:1 and 1:1 stoichiometries have been identified. Here, an antibody whose Fab binds to HA with an unprecedented 2:1 Fab:HA stoichiometry is characterized. The complex has been crystallized and synchrotron data to 3.5 A resolution have been collected. Molecular replacement confirms the stoichiometry of the complex.


Assuntos
Anticorpos Antivirais/química , Complexo Antígeno-Anticorpo/química , Glicoproteínas de Hemaglutininação de Vírus da Influenza/química , Fragmentos Fab das Imunoglobulinas/química , Cristalização , Cristalografia por Raios X , Humanos , Testes de Neutralização
16.
Proteins ; 40(4): 572-8, 2000 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-10899782

RESUMO

The structure of a complex between the hemagglutinin of influenza virus and the Fab of a neutralizing antibody was determined by X-ray crystallography at 2.8 A resolution. This antibody and another which has only 56% sequence identity bind to the same epitope with very similar affinities and in the same orientation. One third of the interactions is conserved in the two complexes; a significant proportion of the interactions that differ are established by residues of the H3 complementarity-determining regions (CDR) which adopt distinct conformations in the two antibodies. This demonstrates that there is a definite flexibility in the selection of antibodies that bind to a given epitope, despite the high affinity of their complexes. This flexibility allows the humoral immune response to be redundant, a feature that may be useful in achieving longer lasting protection against evolving viral pathogens.


Assuntos
Anticorpos/química , Epitopos , Glicoproteínas de Hemaglutininação de Vírus da Influenza/química , Sequência de Aminoácidos , Complexo Antígeno-Anticorpo/química , Cristalografia por Raios X , Fragmentos Fab das Imunoglobulinas/química , Modelos Moleculares , Dados de Sequência Molecular
17.
Nat Struct Biol ; 6(6): 530-4, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10360354

RESUMO

The structure of a complex of influenza hemagglutinin (HA) with a neutralizing antibody shows that the antibody binds to HA at a distance from the virus receptor binding site. Comparison of the properties of this antibody and its Fab with those of an antibody that recognizes an epitope overlapping the receptor binding site leads to two main conclusions. First, inhibition of receptor binding is an important component of neutralization. Second, the efficiency of neutralization by the antibodies ranks in the same order as their avidities for HA, and their large size makes these antibodies highly efficient at neutralization, regardless of the location of their epitope in relation to the virus receptor binding site. These observations provide rationales for the range of antibody specificities that are detected in immune sera and for the distribution of sequence changes on the membrane-distal surface of influenza HAs that occur during 'antigenic drift.'


Assuntos
Anticorpos Antivirais/imunologia , Especificidade de Anticorpos , Glicoproteínas de Hemaglutininação de Vírus da Influenza/química , Orthomyxoviridae/imunologia , Receptores Virais/metabolismo , Animais , Anticorpos Antivirais/química , Afinidade de Anticorpos , Sítios de Ligação , Linhagem Celular , Cristalização , Cristalografia por Raios X , Cães , Epitopos/imunologia , Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia , Glicoproteínas de Hemaglutininação de Vírus da Influenza/metabolismo , Fragmentos Fab das Imunoglobulinas/química , Fragmentos Fab das Imunoglobulinas/imunologia , Imunoglobulina G/química , Imunoglobulina G/imunologia , Modelos Moleculares , Dados de Sequência Molecular , Peso Molecular , Testes de Neutralização , Orthomyxoviridae/crescimento & desenvolvimento , Orthomyxoviridae/metabolismo , Orthomyxoviridae/patogenicidade , Conformação Proteica
18.
Gastroenterol Clin Biol ; 22(8-9): 724-6, 1998.
Artigo em Francês | MEDLINE | ID: mdl-9823562

RESUMO

We report three new cases of chronic interstitial nephritis occurring in two patients with Crohn's disease and one patient with ulcerative colitis treated with mesalazine. In the three cases asymptomatic renal disease was revealed by an increase in serum creatinine which was normal before treatment. Renal biopsy showed features of severe chronic interstitial nephritis. Mesalazine withdrawal and administration of steroids in two cases led to partial improvement of renal function. Mechanism of renal toxicity of mesalazine is unknown. These observations stress the need for monitoring renal function in patients with inflammatory bowel disease treated with mesalazine.


Assuntos
Anti-Inflamatórios não Esteroides/efeitos adversos , Mesalamina/efeitos adversos , Nefrite Intersticial/induzido quimicamente , Adulto , Feminino , Humanos , Masculino
19.
Nat Struct Biol ; 5(2): 119-23, 1998 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9461077

RESUMO

The structure of the hemagglutinin (HA) of a mutant influenza virus that escapes neutralization by a monoclonal antibody shows that the mutation causes changes in HA structure which avoid an energetically less favorable conformation. However, the structure of the mutant HA.Fab complex indicates that the antibody binds selectively to mutant HA in a wild type-like distorted conformation. The association of an antibody with a less favored HA conformation represents an alternative to previously described mechanisms of escape from neutralization by antibodies.


Assuntos
Anticorpos Monoclonais/química , Anticorpos Antivirais/química , Glicoproteínas de Hemaglutininação de Vírus da Influenza/química , Orthomyxoviridae/química , Anticorpos Monoclonais/imunologia , Anticorpos Antivirais/imunologia , Afinidade de Anticorpos , Complexo Antígeno-Anticorpo/química , Complexo Antígeno-Anticorpo/isolamento & purificação , Cristalografia por Raios X , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia , Fragmentos Fab das Imunoglobulinas , Modelos Moleculares , Dados de Sequência Molecular , Mutação , Testes de Neutralização , Orthomyxoviridae/imunologia , Conformação Proteica
20.
Nephrologie ; 18(5): 187-91, 1997.
Artigo em Francês | MEDLINE | ID: mdl-9424596

RESUMO

Intravesical Bacillus Calmette-Guerin has proved to be the most effective treatment of superficial bladder carcinoma. This therapy may induce a renal failure of variable severity, sometimes associated with multiple organ failure. Renal prognosis of this complication is not well defined. We report on a 68 year-old male patient who developed granulomatous hepatitis and acute tubulo-interstitial nephritis with mononuclear infiltrates containing numerous epithelioid cells, following the third course of intravesical BCG. Eleven cases of renal impairment due to intravesical BCG have been previously described, as part of a systemic disease in seven patients. The potential pathophysiological mechanisms of this rare complication are precised.


Assuntos
Injúria Renal Aguda/etiologia , Vacina BCG/efeitos adversos , Nefrite Intersticial/etiologia , Neoplasias da Bexiga Urinária/terapia , Idoso , Vacina BCG/uso terapêutico , Granuloma/etiologia , Granuloma/patologia , Hepatite/etiologia , Humanos , Rim/patologia , Masculino , Nefrite Intersticial/patologia
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