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1.
AIDS Behav ; 25(3): 689-698, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32910354

RESUMO

Driving ability can be diminished amongst people with HIV with associated neurocognitive impairment (NCI). We explore the relationship between HIV status, NCI and driving ability in professional truck drivers. Forty male professional drivers (20 HIV-positive; mean age = 39.20 ± 7.05) completed a neuropsychological test battery, two driving simulator tasks that assessed driving ability, and a driving history and habits questionnaire. A higher proportion of HIV-positive drivers exhibited impaired overall cognitive performance (p ≤ 0.001). Overall, drivers with NCI (defined as z ≤ 1.00) were more likely than those without NCI to crash (p = 0.002). There were no significant between-group (HIV-positive versus HIV-negative) differences with regard to self-reported on-road driving events. Professional drivers with NCI, as measured on a driving simulator, are at increased risk of making driving errors under high-risk conditions compared to their neurocognitively normal counterparts. These data should inform driver health management with regard to annual medical screening and surveillance.


RESUMEN: La capacidad de conducción puede verse disminuida entre las personas con VIH con deterioro neurocognitivo asociado (neurocognitive impairment, NCI). Exploramos la relación entre la situación frente al VIH, el NCI y la capacidad de conducción en conductores profesionales de camiones. Cuarenta conductores profesionales masculinos (20 seropositivos, edad media = 39.20 ± 7.05) completaron una batería de pruebas neuropsicológicas, dos tareas de simulador de conducción que evaluaron la capacidad de conducción y un cuestionario de hábitos y antecedentes de conducción. Una mayor proporción de conductores VIH positivos exhibió un desempeño cognitivo general deficiente (p ≤ 0.001). En general, los conductores con NCI (definido como z ≤ 1.00) tenían más probabilidades de chocar que aquellos sin NCI (p = 0.002). No hubo diferencias significativas entre los grupos (VIH positivo frente a VIH negativo) con respecto a los eventos autoinformados de conducción en carretera. Los conductores profesionales con NCI, según lo medido en un simulador de conducción, tienen un mayor riesgo de cometer errores de conducción en condiciones de alto riesgo en comparación con sus homólogos neurocognitivamente normales. Estos datos deberían informar a la gestión de la salud del conductor en lo que respecta a la vigilancia y los exámenes médicos anuales.


Assuntos
Condução de Veículo/estatística & dados numéricos , Infecções por HIV/complicações , Saúde Ocupacional , Acidentes de Trânsito , Adulto , Condução de Veículo/psicologia , Feminino , Infecções por HIV/epidemiologia , Humanos , Masculino , Destreza Motora , Veículos Automotores , Testes Neuropsicológicos , Inquéritos e Questionários
2.
Eur J Neurol ; 25(5): 790-794, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29437287

RESUMO

BACKGROUND AND PURPOSE: The aim was to determine the genetic background of unknown muscular dystrophy in five French families. METHODS: Twelve patients with limb girdle muscular dystrophy or distal myopathy were clinically evaluated. Gene mutations were identified using targeted exon sequencing and mutated DNAJB6 was tested in vitro. RESULTS: Five patients presented with distal lower limb weakness whilst others had proximal presentation with a variable rate of progression starting at the mean age of 38.5 years. Two novel mutations (c.284A>T, p.Asn95Ile, two families; and c.293_295delATG, p.Asp98del, one family) as well as the previously reported c.279C>G (p.Phe93Leu, two families) mutation in DNAJB6 were identified. All showed a reduced capacity to prevent protein aggregation. CONCLUSIONS: The mutational and phenotypical spectrum of DNAJB6-caused muscle disease is larger than previously reported, including also dysphagia. The originally reported c.279C>G (p.Phe93Leu) mutation is now identified in four different populations and appears to be a mutational hotspot. Our report confirms that some DNAJB6 mutations cause distal-onset myopathy and hence DNAJB6 defects should be considered broadly in dominant muscular dystrophy families.


Assuntos
Miopatias Distais/genética , Proteínas de Choque Térmico HSP40/genética , Chaperonas Moleculares/genética , Distrofia Muscular do Cíngulo dos Membros/genética , Mutação , Proteínas do Tecido Nervoso/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Progressão da Doença , Feminino , França , Humanos , Masculino , Pessoa de Meia-Idade , Debilidade Muscular/genética , Linhagem , Fenótipo
3.
Morphologie ; 102(337): 69-77, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29530649

RESUMO

Most osteolytic tumors are in fact mixed and contain an osteoblastic component associated with the predominant osteolytic areas. This metaplastic woven bone is always evidenced by histological analysis even in the absence of radiological expression. Metaplastic bone formation reflects the activation of new osteoblasts coming from the stimulation of the dormant lining cells. Twelve patients with secondary metastases of the iliac crest evidenced by hot spots on a 99Tc-MBP san were diagnosed by histomorphometry on bone biopsies. Fourier Transformed InfraRed analysis and Imaging (FTIRI) was used on 4µm thick sections of undecalcified bone. The mineralization degree, carbonate substitution, crystallinity and the cross-links ratio of collagen (1660/1690cm-1 bands) were determined. The matrix characteristics were analyzed and imaged in the pre-existing residual bone and in the metaplastic woven bone in the vicinity of the tumor cells. FTIRI provided images of the phosphate, amide and combination of peak ratio after having selected the peaks of interest. In addition, the matrix properties can be measured and compared between the old and newly-formed bones. Woven bone appeared poorly calcified with a low phosphate/amide ratio (P=0.03) crystallinity (P<0.0001) and carbonate substitution (P=0.003). Collagen was less mature as evidenced by lower cross-links (P=0.01). Woven bone associated with bone metastasis appears poorly mineralized and rapidly elaborated by osteoblasts. The collagenous phase of the bone matrix has a low level of reticulation. FTIRI is a powerful tool to measure and visualize the various components of the bone matrix in human diseases.


Assuntos
Densidade Óssea , Neoplasias Ósseas/diagnóstico por imagem , Ílio/diagnóstico por imagem , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Biópsia , Matriz Óssea/diagnóstico por imagem , Matriz Óssea/patologia , Neoplasias Ósseas/patologia , Neoplasias Ósseas/secundário , Estudos de Viabilidade , Feminino , Humanos , Ílio/patologia , Masculino , Osteogênese , Estudos Retrospectivos , Medronato de Tecnécio Tc 99m/administração & dosagem
4.
Clin Genet ; 91(6): 868-880, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28229453

RESUMO

The group of chondrodysplasia with multiple dislocations includes several entities, characterized by short stature, dislocation of large joints, hand and/or vertebral anomalies. Other features, such as epiphyseal or metaphyseal changes, cleft palate, intellectual disability are also often part of the phenotype. In addition, several conditions with overlapping features are related to this group and broaden the spectrum. The majority of these disorders have been linked to pathogenic variants in genes encoding proteins implicated in the synthesis or sulfation of proteoglycans (PG). In a series of 30 patients with multiple dislocations, we have performed exome sequencing and subsequent targeted analysis of 15 genes, implicated in chondrodysplasia with multiple dislocations, and related conditions. We have identified causative pathogenic variants in 60% of patients (18/30); when a clinical diagnosis was suspected, this was molecularly confirmed in 53% of cases. Forty percent of patients remain without molecular etiology. Pathogenic variants in genes implicated in PG synthesis are of major importance in chondrodysplasia with multiple dislocations and related conditions. The combination of hand features, growth failure severity, radiological aspects of long bones and of vertebrae allowed discrimination among the different conditions. We propose key diagnostic clues to the clinician.


Assuntos
Deficiência Intelectual/genética , Anormalidades Musculoesqueléticas/genética , Osteocondrodisplasias/genética , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Estudos de Associação Genética , Humanos , Lactente , Recém-Nascido , Deficiência Intelectual/diagnóstico , Deficiência Intelectual/diagnóstico por imagem , Deficiência Intelectual/fisiopatologia , Masculino , Anormalidades Musculoesqueléticas/diagnóstico , Anormalidades Musculoesqueléticas/diagnóstico por imagem , Anormalidades Musculoesqueléticas/fisiopatologia , Osteocondrodisplasias/diagnóstico , Osteocondrodisplasias/diagnóstico por imagem , Osteocondrodisplasias/fisiopatologia , Radiografia , Sequenciamento do Exoma
5.
J Evol Biol ; 30(12): 2132-2145, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28902471

RESUMO

Patterns of phenotypic and genic frequencies across hybrid zones provide insight into the origin and evolution of reproductive isolation. The Reunion grey white-eye, Zosterops borbonicus, exhibits parapatrically distributed plumage colour forms across the lowlands of the small volcanic island of Reunion (Mascarene archipelago). These forms meet and hybridize in regions that are natural barriers to dispersal (rivers, lava fields). Here, we investigated the relationship among patterns of differentiation at neutral genetic (microsatellite) markers, phenotypic traits (morphology and plumage colour) and niche characteristics across three independent hybrid zones. Patterns of phenotypic divergence revealed that these hybrid zones are among the narrowest ever documented in birds. However, the levels of phenotypic divergence stand in stark contrast to the lack of clear population neutral genetic structure between forms. The position of the hybrid zones coincides with different natural physical barriers, yet is not associated with steep changes in vegetation and related climatic variables, and major habitat transitions are shifted from these locations by at least 18 km. This suggests that the hybrid zones are stabilized over natural dispersal barriers, independently of environmental boundaries, and are not associated with niche divergence. A striking feature of these hybrid zones is the very low levels of genetic differentiation in neutral markers between forms, suggesting that phenotypic divergence has a narrow genetic basis and may reflect recent divergence at a few linked genes under strong selection, with a possible role for assortative mating in keeping these forms apart.


Assuntos
Passeriformes/genética , Animais , Frequência do Gene , Hibridização Genética , Ilhas , Repetições de Microssatélites , Passeriformes/anatomia & histologia , Fenótipo , Isolamento Reprodutivo
6.
Scand J Med Sci Sports ; 27(9): 964-974, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27185578

RESUMO

To effectively prevent sport traumatic brain injury (TBI), means of protection need to be designed and tested in relation to the reality of head impact. This study quantifies head impacts during a typical snowboarding accident to evaluate helmet standards. A snowboarder numerical model was proposed, validated against experimental data, and used to quantify the influence of accident conditions (speed, snow stiffness, morphology, and position) on head impacts (locations, velocities, and accelerations) and injury risk during snowboarding backward falls. Three hundred twenty-four scenarios were simulated: 70% presented a high risk of mild TBI (head peak acceleration >80 g) and 15% presented a high risk of severe TBI (head injury criterion >1000). Snow stiffness, speed, and snowboarder morphology were the main factors influencing head impact metrics. Mean normal head impact speed (28 ± 6 km/h) was higher than equivalent impact speed used in American standard helmet test (ASTM F2040), and mean tangential impact speed, not included in standard tests, was 13.8 (±7 km/h). In 97% of simulated impacts, the peak head acceleration was below 300 g, which is the pass/fail criteria used in standard tests. Results suggest that initial speed, impacted surface, and pass/fail criteria used in helmet standard performance tests do not fully reflect magnitude and variability of snowboarding backward-fall impacts.


Assuntos
Traumatismos Craniocerebrais/prevenção & controle , Dispositivos de Proteção da Cabeça , Esqui/lesões , Aceleração , Acidentes por Quedas , Acidentes , Fenômenos Biomecânicos , Concussão Encefálica/prevenção & controle , Simulação por Computador , Cabeça , Humanos , Manequins
7.
Morphologie ; 100(331): 250-255, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26948676

RESUMO

Fibrodysplasia ossificans progressiva is a very rare heritable disease characterized by a progressive heterotopic endochondal ossification, occurring in the first decade of life, and leading thereafter to a severe ankylosis of the spine, limbs and jaw, with a progressive and severe functional disability. To date the cause of the disease remains unknown and no medical treatment has been proved efficient. It has recently been shown that a recurrent mutation in activation domain of the activin-receptor IA (ACVR1), a BMP receptor, could lead to an abnormal signalling pathway of BMP-4 and contribute to the occurrence of the devastating lesions characteristic of the disease.


Assuntos
Receptores de Ativinas Tipo I/genética , Proteína Morfogenética Óssea 4/metabolismo , Articulações/fisiopatologia , Miosite Ossificante/metabolismo , Ossificação Heterotópica/diagnóstico por imagem , Doenças Raras/metabolismo , Adulto , Anti-Inflamatórios não Esteroides/uso terapêutico , Conservadores da Densidade Óssea/uso terapêutico , Ácido Etidrônico/uso terapêutico , Fraturas Ósseas/etiologia , Regulação da Expressão Gênica , Humanos , Articulações/diagnóstico por imagem , Imageamento por Ressonância Magnética , Masculino , Miosite Ossificante/complicações , Miosite Ossificante/tratamento farmacológico , Miosite Ossificante/genética , Ossificação Heterotópica/tratamento farmacológico , Ossificação Heterotópica/etiologia , Mutação Puntual , Radiografia , Doenças Raras/complicações , Doenças Raras/genética , Transdução de Sinais , Crânio/diagnóstico por imagem , Ultrassonografia
8.
Hernia ; 28(2): 485-494, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38177404

RESUMO

PURPOSE: The width of the Linea alba, which is often gauged by inter-rectus distance, is a key risk factor for incisional hernia and recurrence. Previous studies provided limited descriptions with no consideration for width, location variability, or curvature. We aimed to offer a comprehensive 3D anatomical analysis of the Linea alba, emphasizing its variations across diverse demographics. METHODS: Using open source software, 2D sagittal plane and 3D reconstructions were performed on 117 patients' CT scans. Linea alba length, curvature assessed by the sagitta (the longest perpendicular segment between xipho-pubic line and the Linea alba), and continuous width along the height were measured. RESULTS: The Linea alba had a rhombus shape, with a maximum width at the umbilicus of 4.4 ± 1.9 cm and a larger width above the umbilicus than below. Its length was 37.5 ± 3.6 cm, which increased with body mass index (BMI) (p < 0.001), and was shorter in women (p < 0.001). The sagitta was 2.6 ± 2.2 cm, three times higher in the obese group (p < 0.001), majorated with age (p = 0.009), but was independent of gender (p = 0.212). Linea alba width increased with both age and BMI (p < 0.001-p = 0.002), being notably wider in women halfway between the umbilicus and pubis (p = 0.007). CONCLUSION: This study provides an exhaustive 3D description of Linea alba's anatomical variability, presenting new considerations for curvature. This method provides a patient-specific anatomy description of the Linea alba. Further studies are needed to determine whether 3D reconstruction correlates with pathologies, such as hernias and diastasis recti.


Assuntos
Parede Abdominal , Hérnia Incisional , Humanos , Feminino , Herniorrafia , Parede Abdominal/diagnóstico por imagem , Parede Abdominal/cirurgia , Índice de Massa Corporal , Hérnia Incisional/cirurgia , Obesidade
9.
Morphologie ; 96(313): 40-3, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23022200

RESUMO

A 93 year-old woman with Paget's disease of bone had been treated with etidronate without interruption during 20 years. The daily dose was usual (5mg/kg/day) but this prescription had never been stopped by her physicians. Two fractures had already occurred in pagetic (right tibia) and non pagetic bones (right fibula) within the last 2 years, and she presented rib fractures, another right tibia fracture and right femur fracture during hospitalization time. X-rays films showed major osteolysis of left ulna and right tibia. Blood samples and technetium bone scan brought no evidence for sarcoma or lytic evolution of the disease. A transiliac bone biopsy on non pagetic bone site confirmed the diagnosis of osteomalacia (increased osteoid parameters), with secondary hyperparathyroidism (hook resorption). In Paget's disease of bone, continuous treatment by etidronate may induce generalized osteomalacia, and increase the risk of fracture in both pagetic and non-pagetic bones. Whereas physicians and pharmaceutical industry try to improve the observance of those drugs, this striking observation also points out that a prescription always needs to be updated.


Assuntos
Conservadores da Densidade Óssea/efeitos adversos , Ácido Etidrônico/efeitos adversos , Fraturas Espontâneas/etiologia , Osteíte Deformante/tratamento farmacológico , Osteomalacia/induzido quimicamente , Idoso de 80 Anos ou mais , Fosfatase Alcalina/sangue , Biópsia , Conservadores da Densidade Óssea/administração & dosagem , Conservadores da Densidade Óssea/farmacologia , Conservadores da Densidade Óssea/uso terapêutico , Calcificação Fisiológica/efeitos dos fármacos , Carbonato de Cálcio/uso terapêutico , Colecalciferol/uso terapêutico , Ácido Etidrônico/administração & dosagem , Ácido Etidrônico/farmacologia , Ácido Etidrônico/uso terapêutico , Feminino , Fraturas do Fêmur/etiologia , Fíbula , Humanos , Hiperparatireoidismo Secundário/sangue , Hiperparatireoidismo Secundário/induzido quimicamente , Doença Iatrogênica , Osteíte Deformante/complicações , Osteólise/sangue , Osteólise/induzido quimicamente , Osteólise/diagnóstico por imagem , Osteomalacia/sangue , Osteomalacia/tratamento farmacológico , Hormônio Paratireóideo/sangue , Cintilografia , Fraturas das Costelas/etiologia , Fraturas da Tíbia/etiologia , Ulna/patologia , Vitamina D/análogos & derivados , Vitamina D/sangue
10.
Micron ; 155: 103229, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35149252

RESUMO

In recent years, the coevolution of microorganisms with current antibiotics has increased the mechanisms of bacterial resistance, generating a major health problem worldwide. Bordetella pertussis is a bacterium that causes whooping cough and is capable of adopting different states of virulence, i.e. virulent or avirulent states. In this study, we explored the nanomechanical properties of both virulent and avirulent B. pertussis as exposed to various antibiotics. The nanomechanical studies highlighted that only virulent B. pertussis cells undergo a decrease in their cell elastic modulus and height upon antimicrobial exposure, whereas their avirulent counterparts remain unaffected. This study also permitted to highlight different mechanical properties of individual cells as compared to those growing in close contact with other individuals. In addition, we analyzed the presence on the bacterial cell wall of Filamentous hemagglutinin adhesin (FHA), the major attachment factor produced by virulent Bordetella spp., under different virulence conditions by Force Spectroscopy.


Assuntos
Bordetella pertussis , Coqueluche , Antibacterianos/farmacologia , Humanos , Microscopia de Força Atômica , Fatores de Virulência de Bordetella , Coqueluche/microbiologia
11.
Science ; 245(4918): 638-9, 1989 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-17837619

RESUMO

An important parasitic threat to honey bees, the mite Varroa jacobsoni, is attracted to its major prey, drone larvae, by methyl and ethyl esters of straight-chain fatty acids, in particular methyl palmitate. These esters were extracted from drone larvae with n-hexane and were identified by gas chromatography-mass spectrometry. Their behavioral effect was evaluated with the use of a four-arm airflow olfactometer.

12.
J Biomech ; 42(3): 261-5, 2009 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-19135201

RESUMO

Computational models are developed in injury biomechanics to assess lesions in biological tissues based on mechanical measurements. The linear mechanics of fracture theory (LMFT) is a common approach to establish injuries based on thresholds (such as force or strain thresholds) which are straightforward to implement and computationally efficient. However, LMFT does not apply to non-linear heterogeneous materials and does not have the ability to predict failure onset. This paper proposes the cohesive zone model theory (CZMT) as an alternative. CZMT focuses on the development of behaviour laws for crack initiation and propagation at an interface that apply within a fibrous material or at the interface between materials. With the view of evaluating CZMT for biological tissues, the model developed by Raous et al. [1999. A consistent model coupling adhesion, friction and unilateral contact. Comput. Methods Appl. Mech. Eng., 177, 383-399] was applied to the ligament-to-bone interface in the human knee joint. This model accounts for adhesion, friction and damage at the interface and provides a smooth transition from total adhesion to complete failure through the intensity of adhesion variable. A 2D finite element model was developed to mimic previous experiments, and the model parameters were determined using a dichotomy method. The model showed good results by its ability to predict damage. The extension to a 3D geometry, with an inverse problem approach, is, however, required to better estimate the model parameters values. Although it is computationally costly, CZMT supplements the improvements achieved in microimaging techniques to support the development of micro/macro approaches in biomechanical modelling.


Assuntos
Osso e Ossos/fisiologia , Articulação do Joelho/fisiologia , Ligamentos/fisiologia , Fenômenos Biomecânicos/fisiologia , Análise de Elementos Finitos , Humanos , Modelos Biológicos , Entorses e Distensões/metabolismo , Estresse Mecânico
13.
Clin Biomech (Bristol, Avon) ; 65: 34-40, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30954683

RESUMO

BACKGROUND: Data from biomechanical tissue sample studies of the human digestive tract are highly variable. The aim of this study was to investigate 4 factors which could modify the mechanical response of human colonic specimens placed under dynamic solicitation until tissue rupture: gender, age, shelf-life and conservation method. METHODS: We performed uniaxial dynamic tests of human colonic specimens. Specimens were taken according to three different protocols: refrigerated cadavers without embalming, embalmed cadavers and fresh colonic tissue. A total of 143 specimens were subjected to tensile tests, at a speed of 1 m s-1. FINDINGS: Young's modulus of the different conservation protocols are as follows: embalmed, 3.08 ±â€¯1.99; fresh, 2.97 ±â€¯2.59; and refrigerated 3.17 ±â€¯2.05. The type of conservation does not modify the stiffness of the tissue (p = 0.26) but does modify the stress necessary for rupture (p < 0.001) and the strain required to obtain lesions of the outer layer and the inner layer (p < 0.001 and p < 0.05, respectively). Gender is also a factor responsible for a change in the mechanical response of the colon. The age of the subjects and the shelf-life of the bodies did not represent factors influencing the mechanical behavior of the colon (p > 0.05). INTERPRETATION: The mechanical response of the colon tissue showed a biphasic injury process depending on gender and method of preservation. The age and shelf-life of anatomical subjects do not alter the mechanical response of the colon.


Assuntos
Colo , Módulo de Elasticidade , Embalsamamento , Preservação Biológica/métodos , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Fenômenos Biomecânicos , Cadáver , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ruptura , Fatores Sexuais , Estresse Mecânico , Resistência à Tração , Adulto Jovem
14.
J Biomech ; 91: 102-108, 2019 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-31133391

RESUMO

The aim of this study was to examine the mechanical behavior of the colon using tensile tests under different loading speeds. Specimens were taken from different locations of the colonic frame from refrigerated cadavers. The specimens were submitted to uniaxial tensile tests after preconditioning using a dynamic load (1 m/s), intermediate load (10 cm/s), and quasi-static load (1 cm/s). A total of 336 specimens taken from 28 colons were tested. The stress-strain analysis for longitudinal specimens indicated a Young's modulus of 3.17 ±â€¯2.05 MPa under dynamic loading (1 m/s), 1.74 ±â€¯1.15 MPa under intermediate loading (10 cm/s), and 1.76 ±â€¯1.21 MPa under quasi-static loading (1 cm/s) with p < 0.001. For the circumferential specimen, the stress-strain curves indicated a Young's modulus of 3.15 ±â€¯1.73 MPa under dynamic loading (1 m/s), 2.14 ±â€¯1.3 MPa under intermediate loading (10 cm/s), and 0.63 ±â€¯1.25 MPa under quasi-static loading (1 cm/s) with p < 0.001. The curves reveal two types of behaviors of the colon: fast break behavior at high speed traction (1 m/s) and a lower break behavior for lower speeds (10 cm/s and 1 cm/s). The circumferential orientation required greater levels of stress and strain to obtain lesions than the longitudinal orientation. The presence of taeniae coli changed the mechanical response during low-speed loading. Colonic mechanical behavior varies with loading speeds with two different types of mechanical behavior: more fragile behavior under dynamic load and more elastic behavior for quasi-static load.


Assuntos
Colo/fisiologia , Fenômenos Biomecânicos , Cadáver , Módulo de Elasticidade , Humanos , Estresse Mecânico , Suporte de Carga
15.
Mol Vis ; 14: 1912-28, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18958307

RESUMO

PURPOSE: Choroidal melanoma is the most common primary malignant ocular tumor in human adults. Relevant mouse models of human uveal melanoma still remain to be developed. We have studied the transgenic mouse strain, Tyrp-1-TAg, to try to gain insight into possible molecular mechanisms common to pigmented ocular neoplasms occurring spontaneously in the eyes of these mice and human choroidal melanoma. The role of two members of the ETS (E26 avian leukemia oncogene) family of transcription factors, ETS-1 and ETS-2, has been investigated in many cancers but has not yet been studied in ocular tumors. METHODS: This is the first study describing the production and distribution of ETS-1 and ETS-2 mRNAs and proteins using in situ hybridization and immunohistochemistry in murine ocular tissue sections of normal control eyes and tumoral eyes from mice of the same age. Using semi-quantitative reverse-transcription polymerase chain reaction (RT-PCR) and western blots experiments, we compared changes in ETS-1 and ETS-2 expression, their protein levels, and the regulation of some of their target gene expressions at different stages of the ocular tumoral progression in the transgenic mouse model, Tyrp-1-TAg, with those in normal eyes from control mice of the same age. RESULTS: In normal control adult mouse eyes, ETS-1 was mostly present in the nuclei of all neuroretinal layers whereas ETS-2 was mostly localized in the cytosol of the cell bodies of these layers with a smaller amount present in the nuclei. Both were found in the retinal pigmentary epithelium (RPE). ETS-1 and ETS-2 mRNA and protein levels were much higher in the ocular tissues of Tyrp-1-TAg mice than in control ocular tissues from wild-type mice. This upregulation was correlated with tumor progression. We also demonstrated upregulation of ETS-1 and ETS-2 target expressions in Tyrp-1-TAg mice when comparing with the same target expressions in control mice. CONCLUSIONS: Our findings suggest that ETS-1 and ETS-2 are upregulated in ocular tumors derived from the retinal epithelium and may be involved in one or several signaling pathways that activate the expression of a set of genes involved in ocular tumor progression such as those encoding ICAM-1 (intercellular adhesion molecule-1), PAI-1 (Plasminogen activator inhibitor-1), MCP-1 (monocyte chemoattractant protein-1) and p16 (Cyclin dependent kinase inhibitor 2A).


Assuntos
Neoplasias Oculares/genética , Regulação Neoplásica da Expressão Gênica , Pigmentação/genética , Proteína Proto-Oncogênica c-ets-1/genética , Proteína Proto-Oncogênica c-ets-2/genética , Regulação para Cima/genética , Animais , Quimiocina CCL2/genética , Quimiocina CCL2/metabolismo , Inibidor p16 de Quinase Dependente de Ciclina/genética , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Modelos Animais de Doenças , Olho/metabolismo , Olho/patologia , Neoplasias Oculares/metabolismo , Neoplasias Oculares/patologia , Humanos , Molécula 1 de Adesão Intercelular/genética , Molécula 1 de Adesão Intercelular/metabolismo , Camundongos , Camundongos Transgênicos , Inibidor 1 de Ativador de Plasminogênio/genética , Inibidor 1 de Ativador de Plasminogênio/metabolismo , Transporte Proteico , Proteína Proto-Oncogênica c-ets-1/metabolismo , Proteína Proto-Oncogênica c-ets-2/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
16.
Ann Biol Clin (Paris) ; 66(2): 157-64, 2008.
Artigo em Francês | MEDLINE | ID: mdl-18390426

RESUMO

OBJECTIVES: to evaluate specificity and sensibility of the rheumatoid factors (RF), the anti-cyclic citrullinated peptide antibodies (CCP) and the anti-keratin antibodies (AKA) according to the rheumatoid arthritis (RA) diagnosis; pathology other than RA with at least one of these marker positive; the significance of the flocculent fluorescence of the antibodies AKA by indirect immunofluorescence (IIF). METHOD: two hundred forty height patients were studied: 121 RA, 89 inflammatory rheumatisms, 23 non inflammatory rheumatisms, and 15 non rheumatic affections. The RF was investigated by nephelometry, the anti-CCP by immunofluorometry and the AKA by IIF on rat oesophagus. RESULTS: specificity and sensibility were respectively in a retrospective manner: 68% and 83% for the RF, 95% and 76% for the anti- CCP, 83% and 40% for the AKA during RA with evolution of less than one year. The rates of agreements were: RF versus CCP: 81%, RF versus AKA: 57%, CCP versus AKA: 73%. Twelve patients with pathologies different from RA have positive anti-CCP or AKA. Thirty three of the patients with anti-CCP level superior to 130 U/mL have flocculent AKA versus only 5% when the anti-CCP are lower than 130 U/mL. CONCLUSION: the RF and the anti-CCP are complementary in RA. Autoimmune and neoplasic pathologies are sometimes responsible for the positivity of the anti-CCP and the AKA. The flocculent aspect of AKA in IIF may be associated with raised concentrations of anti-CCP.


Assuntos
Artrite Reumatoide/diagnóstico , Artrite Reumatoide/imunologia , Autoanticorpos/sangue , Queratinas/imunologia , Peptídeos Cíclicos/imunologia , Fator Reumatoide/sangue , Biomarcadores , Interpretação Estatística de Dados , Ensaio de Imunoadsorção Enzimática , Testes de Floculação , Técnica Indireta de Fluorescência para Anticorpo , Seguimentos , Humanos , Estudos Multicêntricos como Assunto , Nefelometria e Turbidimetria , Estudos Retrospectivos , Sensibilidade e Especificidade , Fatores de Tempo
17.
Mol Vis ; 13: 1412-27, 2007 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-17768378

RESUMO

PURPOSE: Musashi-1 (Msi1) is an RNA-binding protein produced in various types of stem cells including neural stem/progenitor cells and astroglial progenitor cells in the vertebrate central nervous system. Other RNA-binding proteins such as Pumilio-1, Pumilio-2, Staufen-1, and Staufen-2 have been characterized as potential markers of several types of stem or progenitor cells. We investigated the involvement of Msi1 in mouse eye development and adult mouse eye functions by analyzing the profile of Msi1 production in all ocular structures during development and adulthood. METHODS: We studied Msi1 production by in situ hybridization and immunohistochemistry of ocular tissue sections and by semi-quantitative RT-PCR and western blot analysis from the embryonic stage of 12.5 days post coitum (E12.5 dpc) when the first retinal ganglion cells (RGCs) begin to appear to the adult stage when all retinal cell types are present. RESULTS: Msi1 mRNA was present at all studied stages of eye development. Msi1 protein was detected in the primitive neuroblastic layer (NbL), the ganglion cell layer (GCL), and in all major differentiated neurons of postnatal developing and adult retinae. During postnatal developing stages, faint diffuse Msi1 protein staining is converted to a more specific distribution once mouse retina is fully differentiated. The most striking result of our study concerns the large amounts of Msi1 protein and mRNA in several unexpected sites of adult mouse eyes including the corneal epithelium and endothelium, stromal keratocytes, progenitor cells of the limbus, equatorial lens stem cells, differentiated lens epithelial cells, and differentiating lens fibers. Msi1 was also found in the pigmented and nonpigmented cells of the ciliary processes, the melanocytes of the ciliary body, the retinal pigment epithelium, differentiated retinal neurons, and most probably in the retinal glial cells such as Müller glial cells, astrocytes, and the oligodendocytes surrounding the axons of the optic nerve. Msi1 expression was detected in the outer plexiform layer, the inner plexiform layer, and the nerve fiber layer of fully differentiated adult retina. CONCLUSIONS: We provide here the first demonstration that the RNA-binding protein, Msi1, is produced in mouse eyes from embryonic stages until adulthood. The relationship between the presence of Msi1 in developing ocular compartments and the possible stem/progenitor cell characteristics of these compartments remains unclear. Finally, the expression of Msi1 in several different cell types in the adult eye is extremely intriguing and should lead to further attempts to unravel the role of Msi1 in cellular and subcellular RNA metabolism and in the control of translational processes in adult eye cells particularly in adult neuronal dendrites, axons, and synapses.


Assuntos
Olho/embriologia , Olho/metabolismo , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Animais , Animais Recém-Nascidos , Especificidade de Anticorpos , Olho/citologia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Cristalino/citologia , Cristalino/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Retina/metabolismo
18.
Mol Biol Cell ; 8(1): 145-56, 1997 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9017602

RESUMO

The distribution of the ribosomal genes (rDNA) and the upstream binding factor (UBF), correlatively with their RNA transcripts, was investigated in G1, S-phase, and G2. rDNA was distributed in nucleoli, with alternate sites of clustered and dispersed genes. UBF was found associated with some but not all clustered genes and proportionally more with dispersed genes. It was distributed in several foci that were more numerous and heterogeneous in size during G2 than G1. We suggest that UBF associated with rDNA during S-phase because its nucleolar amount increased during that time and remained stable in G2. 5,6-Dichloro-1-beta-D-ribofuranosylbenzimidazole treatment indicated a similar amount of UBF per transcription unit, and consequently heterogeneous size of the UBF foci can represent a variable number of transcription units per foci. Direct visualization of the transcripts demonstrated that only part of UBF is associated with active transcription and that rDNA distribution varied with transcription. We propose that in the same rDNA locus three types of configuration coexist that are correlated with gene activity: 1) clustered genes without UBF; 2) clustered genes with UBF, of which some are associated with transcription; and 3) dispersed genes with UBF and transcription. These results support the hypothesis that rDNA transcription involved several steps of regulation acting successively and locally in the same locus to promote the repressed clustered genes to become actively transcribed dispersed genes.


Assuntos
DNA Ribossômico/química , DNA Ribossômico/metabolismo , Proteínas de Ligação a DNA/metabolismo , Proteínas Pol1 do Complexo de Iniciação de Transcrição , RNA Ribossômico/genética , Fatores de Transcrição/metabolismo , Transcrição Gênica , Animais , Nucléolo Celular/fisiologia , Células Cultivadas , DNA Ribossômico/genética , Proteínas de Ligação a DNA/genética , Interfase , Rim/citologia , Modelos Moleculares , Conformação de Ácido Nucleico , RNA Polimerase I/metabolismo , Precursores de RNA/genética , Precursores de RNA/metabolismo , Fatores de Transcrição/genética
19.
J Thromb Haemost ; 15(10): 2065-2075, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28771917

RESUMO

Essentials No humanized monoclonal antibody was available to study heparin-induced thrombocytopenia (HIT). We developed the first anti-platelet factor 4 (PF4)/heparin antibody with a human Fc fragment. This antibody (5B9) fully mimics the effects of human HIT antibodies. 5B9 binds two regions within PF4 that may be critical for the pathogenicity of HIT antibodies. SUMMARY: Background The diagnosis of heparin-induced thrombocytopenia (HIT) is based on clinical and biological criteria, but a standard is lacking for laboratory assays. Moreover, no humanized HIT antibody is available for pathophysiological studies. Objective To characterise 5B9, a chimeric monoclonal antibody, which fully mimics the effects of human HIT antibodies. Methods/Results 5B9, a chimeric anti-platelet factor 4/heparin complexes IgG1 antibody, was obtained after immunizing specific transgenic mice. 5B9 induced heparin FcγRIIA-dependent platelet aggregation and tissue factor mRNA synthesis in monocytes. It also induced significant thrombocytopenia and thrombin generation in mice expressing human PF4 and FcγRIIA receptors. The binding of 5B9 to PF4/H complexes was inhibited by 15 of 25 HIT plasma samples and only three of 25 samples containing non-pathogenic anti-PF4/H antibodies. KKO, a murine IgG2b HIT antibody, also inhibited the binding of 5B9 to PF4/H, suggesting that epitopes recognized by both antibodies are close. A docking analysis based on VH and VL sequences of 5B9 showed that binding of 5B9 Fab to PF4 involved 12 and 12 residues in B and D monomers, respectively, including seven previously identified as critical to the formation of a PF4/KKO complex. Two regions (Asp-7 to Thr-15 and Ala-32 to Thr-38) therefore appeared important for the binding of 5B9 and KKO on PF4 modified by heparin. Conclusions 5B9 is the first anti-PF4/H monoclonal antibody with a human Fc fragment, which induces similar cellular activation as HIT antibodies. Moreover, 5B9 binds epitopes within PF4 that are likely to be critical for the pathogenicity of HIT antibodies.


Assuntos
Anticorpos Monoclonais Humanizados/imunologia , Heparina/imunologia , Fragmentos Fc das Imunoglobulinas/imunologia , Imunoglobulina G/imunologia , Fator Plaquetário 4/imunologia , Trombocitopenia/imunologia , Animais , Anticorpos Monoclonais Humanizados/biossíntese , Especificidade de Anticorpos , Sítios de Ligação , Plaquetas/imunologia , Plaquetas/metabolismo , Degranulação Celular , Modelos Animais de Doenças , Heparina/administração & dosagem , Heparina/efeitos adversos , Humanos , Hibridomas , Imunização , Epitopos Imunodominantes , Fragmentos Fc das Imunoglobulinas/biossíntese , Camundongos Endogâmicos BALB C , Camundongos Transgênicos , Simulação de Acoplamento Molecular , Neutrófilos/imunologia , Neutrófilos/metabolismo , Agregação Plaquetária , Fator Plaquetário 4/administração & dosagem , Fator Plaquetário 4/genética , Ligação Proteica , Receptores de IgG/genética , Receptores de IgG/imunologia , Trombocitopenia/sangue , Trombocitopenia/induzido quimicamente , Fatores de Tempo
20.
Ann Biol Clin (Paris) ; 64(2): 162-5, 2006.
Artigo em Francês | MEDLINE | ID: mdl-16556527

RESUMO

Anti-cyclic citrullinated antibodies occurrence is a recent serological marker for rheumatoid arthritis. The aim of our study was to evaluate the measurement of these antibodies by a new fluorescent-enzyme immunoassay, called EliA CCP, fully automated onto UniCAP 100. This evaluation reveals correct and shows a within run imprecision of 4.6 to 10.5 % and a between-assay imprecision of 9,5 %. The comparison with an Elisa method (Euroimmun) shows a good correlation of anti-CCP concentrations without any major discrepancy.


Assuntos
Artrite Reumatoide/sangue , Artrite Reumatoide/diagnóstico , Autoanticorpos/sangue , Peptídeos Cíclicos/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Fluorometria , Humanos , Imunoensaio/métodos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes
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