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1.
Ecol Evol ; 14(7): e70012, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39026946

RESUMO

In flying animals, wing morphology is typically assumed to influence flight behaviours. Whether seasonal polymorphism in butterfly morphology is linked to adaptive flight behaviour remains unresolved. Here, we compare the flight behaviours and wing morphologies of the spring and summer forms of two closely related butterfly species, Pieris napi and P. rapae. We first quantify three-dimensional flight behaviour by reconstructing individual flight trajectories using stereoscopic high-speed videography in an experimental outdoor cage. We then measure wing size and shape, which are characteristics assumed to influence flight behaviours in butterflies. We show that seasonal, but not interspecific, differences in flight behaviour might be associated with divergent forewing shapes. During spring, Pieris individuals are small and have elongated forewings, and generally fly at low speed and acceleration, while having a high flight curvature. On the contrary, summer individuals are larger and exhibit rounded forewings. They fly at high speed and acceleration, while having high turning acceleration and advance ratio. Our study provides one of the first quantitative pieces of evidence of different flight behaviours between seasonal forms of two Pieris butterfly species. We discuss the possibility that this co-divergence in flight behaviour and morphology is an adaptation to distinct seasonal environments. Properly identifying the mechanisms underpinning such divergence, nonetheless, requires further investigations to disentangle the interacting effects of microhabitats, predator community, parasitoid pressure and behavioural differences between sexes.

2.
Sci Rep ; 13(1): 16902, 2023 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-37803037

RESUMO

Patients with spinal cord injury (SCI) suffer from major bowel dysfunction, whose exact pathophysiology, particularly the involvement of the enteric nervous system or epithelial dysfunction is poorly understood. Herein, we aimed to characterize the mucosal biopsies of the right and left colon in SCI patients vs controls (CT): (1) remodeling of key enteric neurotransmitters, (2) remodeling of enteroendocrine cells, and (3) mucosal inflammation compared to those in controls. In SCI, mucosal ACh concentration was lower in the right colon as compared to CT, but no change was observed in the left colon, and AChE expression was lower in both the right and left colons than in CT. While the VIP concentration was similar in the right and left colons, VIP mRNA expression was increased in the right colon and decreased in the left colon, in SCI patients as compared to CT. Interestingly, 5-HT concentration was reduced in the left colon but not in the right colon in SCI patients. Moreover, in SCI patients, as compared to CT, SERT mRNA expression was selectively increased in the left colon while TPH1 mRNA expression was increased in the right and left colons. Although mucosal TNFα and IL-1ß mRNA expression did not significantly differ between SCI and CT groups, we identified a significant positive correlation between TNFα and IL-1ß mRNA expression and left colon transit time in the SCI group. In conclusion, region-specific changes occur in the enteric neurotransmitter, serotonergic, and inflammatory pathways in the colon of SCI patients. The significant correlations between these pathways and clinical parameters in the left colon further set a scientific basis for designing therapeutic targets to improve colonic motor dysfunction in patients.Biobank information: Spinal cord injury patients: PHRC ConstiCAPE-clinical trial NCT02566746. Controls: Anosain-clinical trial NCT03054415 and biobank of the "Institut des Maladies de l'Appareil Digestif (IMAD)" registered under number DC-2008-402.


Assuntos
Sistema Nervoso Entérico , Traumatismos da Medula Espinal , Humanos , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo , Colo/patologia , Sistema Nervoso Entérico/metabolismo , Células Enteroendócrinas , Neurotransmissores/metabolismo , RNA Mensageiro/metabolismo , Medula Espinal
3.
J Exp Biol ; 225(15)2022 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-35851402

RESUMO

Habitat specialization can influence the evolution of animal movement in promoting divergent locomotor abilities adapted to contrasting environmental conditions, differences in vegetation clutter or predatory communities. While the effect of habitat on the evolution of locomotion and particularly escape performance has been well investigated in terrestrial animals, it remains understudied in flying animals. Here, we investigated whether specialization of Morpho butterfly species into different vertical strata of the Amazonian forest affects the performance of upward escape flight manoeuvres. Using stereoscopic high-speed videography, we compared the climbing flight kinematics of seven Morpho species living either in the forest canopy or in the understory. We show that butterflies from canopy species display strikingly higher climbing speed and steeper ascent angle compared with understory species. Although climbing speed increased with wing speed and angle of attack, the higher climb angle observed in canopy species was best explained by their higher body pitch angle, resulting in more upward-directed aerodynamic thrust forces. Climb angle also scales positively with weight-normalized wing area, and this weight-normalized wing area was higher in canopy species. This shows that a combined divergence in flight behaviour and morphology contributes to the evolution of increased climbing flight abilities in canopy species.


Assuntos
Borboletas , Voo Animal , Adaptação Fisiológica , Animais , Fenômenos Biomecânicos , Ecossistema , Asas de Animais/anatomia & histologia
4.
Nat Commun ; 12(1): 7248, 2021 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-34903755

RESUMO

The coexistence of closely-related species in sympatry is puzzling because ecological niche proximity imposes strong competition and reproductive interference. A striking example is the widespread wing pattern convergence of several blue-banded Morpho butterfly species with overlapping ranges of distribution. Here we perform a series of field experiments using flying Morpho dummies placed in a natural habitat. We show that similarity in wing colour pattern indeed leads to interspecific territoriality and courtship among sympatric species. In spite of such behavioural interference, demographic inference from genomic data shows that sympatric closely-related Morpho species are genetically isolated. Mark-recapture experiments in the two most closely-related species unravel a strong temporal segregation in patrolling activity of males. Such divergence in phenology reduces the costs of reproductive interference while simultaneously preserving the benefits of convergence in non-reproductive traits in response to common ecological pressures. Henceforth, the evolution of multiple traits may favour species diversification in sympatry by partitioning niche in different dimensions.


Assuntos
Borboletas/genética , Especiação Genética , Simpatria , Animais , Mimetismo Biológico , Borboletas/classificação , Corte , Ecossistema , Masculino , Isolamento Reprodutivo , Análise Espaço-Temporal , Territorialidade , Asas de Animais
5.
Science ; 374(6571): 1158-1162, 2021 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-34822295

RESUMO

The diversity of flying animals suggests that countless combinations of flight morphologies and behaviors have evolved with specific lifestyles, thereby exploiting diverse aerodynamic mechanisms. How morphology, flight behavior, and aerodynamic properties together diversify with contrasting ecology remains to be elucidated. We studied the adaptive codivergence in wing shape, flight behavior, and aerodynamic efficiency among Morpho butterflies living in different forest strata by combining high-speed videography in the field with morphometric analyses and aerodynamic modeling. By comparing canopy and understory species, we show that adaptation to an open canopy environment resulted in increased glide efficiency. Moreover, this enhanced glide efficiency was achieved by different canopy species through distinct combinations of flight behavior, wing shape, and aerodynamic mechanisms, highlighting the multiple pathways of adaptive evolution.


Assuntos
Evolução Biológica , Borboletas/anatomia & histologia , Borboletas/fisiologia , Voo Animal , Florestas , Asas de Animais/anatomia & histologia , Asas de Animais/fisiologia , Adaptação Fisiológica , Animais , Borboletas/genética , Masculino , Filogenia , Seleção Genética
6.
Sci Rep ; 11(1): 18042, 2021 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-34508141

RESUMO

Owing to their role in activating enzymes essential for bacterial viability and pathogenicity, phosphopantetheinyl transferases represent novel and attractive drug targets. In this work, we examined the inhibitory effect of the aminido-urea 8918 compound against the phosphopantetheinyl transferases PptAb from Mycobacterium abscessus and PcpS from Pseudomonas aeruginosa, two pathogenic bacteria associated with cystic fibrosis and bronchiectasis, respectively. Compound 8918 exhibits inhibitory activity against PptAb but displays no activity against PcpS in vitro, while no antimicrobial activity against Mycobacterium abscessus or Pseudomonas aeruginosa could be detected. X-ray crystallographic analysis of 8918 bound to PptAb-CoA alone and in complex with an acyl carrier protein domain in addition to the crystal structure of PcpS in complex with CoA revealed the structural basis for the inhibition mechanism of PptAb by 8918 and its ineffectiveness against PcpS. Finally, in crystallo screening of potent inhibitors from the National Cancer Institute library identified a hydroxypyrimidinethione derivative that binds PptAb. Both compounds could serve as scaffolds for the future development of phosphopantetheinyl transferases inhibitors.


Assuntos
Proteínas de Bactérias/química , Inibidores Enzimáticos/química , Pirimidinonas/química , Transferases (Outros Grupos de Fosfato Substituídos)/química , Ureia/química , Proteínas de Bactérias/antagonistas & inibidores , Sítios de Ligação , Inibidores Enzimáticos/farmacologia , Conformação Molecular , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Mycobacterium abscessus/enzimologia , Ligação Proteica , Pseudomonas aeruginosa/enzimologia , Proteínas Recombinantes , Relação Estrutura-Atividade , Especificidade por Substrato , Transferases (Outros Grupos de Fosfato Substituídos)/antagonistas & inibidores , Ureia/análogos & derivados , Ureia/farmacologia
7.
Trauma Violence Abuse ; 22(2): 318-338, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-31122160

RESUMO

Children placed in residential treatment centers (RTCs) typically present challenging behavior including aggression. In this context, restraint and seclusion (R&S) are seen as "last resort" strategies for educators to manage youth aggression. The use of R&S is controversial, as they can lead to psychological and physical consequences for both the client and the care provider and have yet to be empirically validated as therapeutic. The objectives of this systematic review are to identify the factors related to R&S use in RTCs for youth and to review the interventions aiming to reduce the use of R&S. The identification of these factors is the first step to gaining a better understanding of the decision-making process leading to the use of R&S and ultimately to reducing the use of these strategies to a minimum. Thus, the present systematic review was conducted by searching PubMed, CINAHL, ERIC, and PsycNET for articles published between 2002 and 2017. Key words used were synonyms of R&S, youth, and RTCs. Thirty-one studies met the inclusion criteria: must report on factors affecting the use of R&S in RTCs, must be conducted in RTCs for youth under the age of 21, and must report on original and empirical data. Factors related to the characteristics of the client, the care provider, and the environment, as well as to the implementation of programs for the reduction of R&S, were found to influence the use of R&S in RTCs. A conceptual model is presented. The implementation of programs to reduce R&S use is discussed.


Assuntos
Isolamento de Pacientes , Tratamento Domiciliar , Restrição Física , Adolescente , Agressão , Criança , Humanos , Isolamento de Pacientes/estatística & dados numéricos , Restrição Física/estatística & dados numéricos , Fatores de Risco
8.
J Exp Biol ; 222(Pt 16)2019 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-31371404

RESUMO

Flying insects frequently experience wing damage during their life. Such irreversible alterations of wing shape affect flight performance and ultimately fitness. Insects have been shown to compensate for wing damage through various behavioural adjustments, but the importance of damage location over the wings has scarcely been studied. Using natural variation in wing damage, we tested how the loss of different wing parts affects flight performance. We quantified flight performance in two species of large butterflies, Morpho helenor and Morpho achilles, caught in the wild and displaying large variation in the extent and location of wing damage. We artificially generated more severe wing damage in our sample to contrast natural versus higher magnitude wing loss. Wing shape alteration across our sample was quantified using geometric morphometrics to test the effect of different damage distributions on flight performance. Our results show that impaired flight performance clearly depends on damage location over the wings, pointing to a relative importance of different wing parts for flight. A deteriorated forewing leading edge most critically affected flight performance, specifically decreasing flight speed and the proportion of gliding flight. In contrast, the most frequent natural damage, deteriorated wing margin, had no detectable effect on flight behaviour. Damage located on the hindwings - although having a limited effect on flight - was associated with reduced flight height, suggesting that the forewings and hindwings play different roles in butterfly flight. By contrasting harmless and deleterious consequences of various types of wing damage, our study highlights different selective regimes acting on morphological variations of butterfly wings.


Assuntos
Evolução Biológica , Borboletas/anatomia & histologia , Asas de Animais/anatomia & histologia , Animais , Feminino , Voo Animal , Masculino
9.
Biol Rev Camb Philos Soc ; 94(4): 1261-1281, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30793489

RESUMO

Butterflies display extreme variation in wing shape associated with tremendous ecological diversity. Disentangling the role of neutral versus adaptive processes in wing shape diversification remains a challenge for evolutionary biologists. Ascertaining how natural selection influences wing shape evolution requires both functional studies linking morphology to flight performance, and ecological investigations linking performance in the wild with fitness. However, direct links between morphological variation and fitness have rarely been established. The functional morphology of butterfly flight has been investigated but selective forces acting on flight behaviour and associated wing shape have received less attention. Here, we attempt to estimate the ecological relevance of morpho-functional links established through biomechanical studies in order to understand the evolution of butterfly wing morphology. We survey the evidence for natural and sexual selection driving wing shape evolution in butterflies, and discuss how our functional knowledge may allow identification of the selective forces involved, at both the macro- and micro-evolutionary scales. Our review shows that although correlations between wing shape variation and ecological factors have been established at the macro-evolutionary level, the underlying selective pressures often remain unclear. We identify the need to investigate flight behaviour in relevant ecological contexts to detect variation in fitness-related traits. Identifying the selective regime then should guide experimental studies towards the relevant estimates of flight performance. Habitat, predators and sex-specific behaviours are likely to be major selective forces acting on wing shape evolution in butterflies. Some striking cases of morphological divergence driven by contrasting ecology involve both wing and body morphology, indicating that their interactions should be included in future studies investigating co-evolution between morphology and flight behaviour.


Assuntos
Adaptação Fisiológica/genética , Borboletas/anatomia & histologia , Borboletas/genética , Voo Animal/fisiologia , Asas de Animais/anatomia & histologia , Animais , Evolução Biológica
10.
Violence Vict ; 33(3): 547-562, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-30567864

RESUMO

The objective of this study was to assess whether the psychological distress of young men and women involved in intimate partner violence (IPV) is predicted by their reported role in the pattern of violence. Dyadic structural equation modeling (SEM) analyses were performed on a sample of 205 young couples, controlling for income, cohabitation, children, and the length of the relationship. Findings revealed that the most common reported pattern of IPV was mutual in nature. Reported bidirectional violence within the couple was related to distress for both sexes. The couple's income and the length of their relationship were negatively associated with psychological distress, namely for young women. Findings point to the importance of considering therapy in a couple-context.


Assuntos
Violência por Parceiro Íntimo/psicologia , Estresse Psicológico , Feminino , Humanos , Masculino , Psicometria , Adulto Jovem
11.
Child Abuse Negl ; 81: 308-321, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29778040

RESUMO

Child protection workers (CPWs) are frequently exposed to client violence, both psychological and physical, in their line of work whether they operate in the community or in residential settings. Despite this known vulnerability, research on the subject has lagged. The current study sought to analyze CPWs' experiences with client violence, their interpretation of it, its perceived consequences and their coping strategies. Specifically, 30 CPWs working both in the community and in residential settings, took part in an in-depth, semi-structured interview. A thematic analysis revealed that CPWs view client violence as a recurring and pervasive problem in their line of work. Residential workers described a greater frequency of violence, especially physical violence. CPWs however perceived violence differently, with some viewing this problem as 'part-of-the-job' while others described client violence as a 'call-for-help' on behalf of clients. Perceived consequences varied in severity and breath. CPWs reported consequences at the psychological (e.g. fear, hypervilence, sadness, nightmares), organizational (e.g. loss of motivation, turnover intention, sick leaves) and clinical levels (e.g. emotional detachment from clients, avoiding clients). CPWs also described numerous coping strategies, some effective while others appeared short-sighted. This study concludes with recommendations with regards to client violence in child protection work.


Assuntos
Adaptação Psicológica , Serviços de Proteção Infantil , Exposição Ocupacional , Assistentes Sociais/psicologia , Violência , Adulto , Criança , Medo , Feminino , Humanos , Entrevistas como Assunto , Masculino , Pesquisa Qualitativa , Percepção Social , Violência/psicologia
12.
Prenat Diagn ; 36(6): 523-9, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27018091

RESUMO

OBJECTIVE: Sex chromosome aneuploidies are frequently detected fortuitously in a prenatal diagnosis. Most cases of 47, XXX and 47, XYY syndromes are diagnosed in this context, and parents are thus faced with an unexpected situation. The objective of the present study was to characterize a French cohort of prenatally diagnosed cases of 47, XXX and 47, XYY and to evaluate the termination of pregnancy (TOP) rate before and after France's implementation of multidisciplinary centres for prenatal diagnosis in 1997. METHODS: This retrospective study identified respectively 291 and 175 cases of prenatally diagnosed 47, XXX and 47, XYY between 1976 and 2012. For each case, the indication, maternal age, karyotype and outcome were recorded. RESULTS: Most diagnoses of the two conditions were fortuitous. The occurrence of 47, XXX was associated with advanced maternal age. The overall TOP rate was higher for 47, XXX (22.9%) than for 47, XYY (14.6%), although this difference was not statistically significant. However, the TOP rates fell significantly after 1997 (from 41.1% to 11.8% for 47, XXX and from 25.8% to 6.7% for 47, XYY). CONCLUSION: The TOP rates after prenatal diagnoses of 47, XXX and 47, XYY fell significantly after 1997, following France's implementation of multidisciplinary centres for prenatal diagnosis. © 2016 John Wiley & Sons, Ltd.


Assuntos
Aborto Induzido/estatística & dados numéricos , Aborto Espontâneo/epidemiologia , Resultado da Gravidez/epidemiologia , Transtornos do Cromossomo Sexual no Desenvolvimento Sexual/epidemiologia , Transtornos dos Cromossomos Sexuais/epidemiologia , Cariótipo XYY/epidemiologia , Aborto Induzido/tendências , Adulto , Amniocentese , Amostra da Vilosidade Coriônica , Cromossomos Humanos X , Estudos de Coortes , Feminino , Morte Fetal , França/epidemiologia , Humanos , Idade Materna , Gravidez , Diagnóstico Pré-Natal , Estudos Retrospectivos , Aberrações dos Cromossomos Sexuais , Transtornos dos Cromossomos Sexuais/diagnóstico , Transtornos dos Cromossomos Sexuais/diagnóstico por imagem , Transtornos do Cromossomo Sexual no Desenvolvimento Sexual/diagnóstico , Transtornos do Cromossomo Sexual no Desenvolvimento Sexual/diagnóstico por imagem , Trissomia/diagnóstico , Cariótipo XYY/diagnóstico , Cariótipo XYY/diagnóstico por imagem
13.
Prenat Diagn ; 34(12): 1133-8, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24961405

RESUMO

OBJECTIVES: The objectives of this study were to report pregnancy outcomes after prenatal diagnosis of Turner syndrome (TS) and to compare and assess termination of pregnancy rates during two periods. The intervals selected were before and after 1997 when multidisciplinary centers for prenatal diagnosis (MCPDs) were established in France. METHODS: A database of 975 cases of TS diagnosed between 1980 and 2012 was created from 21 French cytogenetics laboratories. For each case, the karyotype indication, maternal age, year of prenatal testing, sampling procedure, karyotype, associated ultrasound findings, and outcomes were recorded. RESULTS: Karyotypes were mainly performed because of abnormal sonographic findings (84%). Before 1997, there were no changes in the rate of termination (90%) of affected fetuses. After 1997, the rate fell to 80%. This decrease was mainly observed in cases of mosaicism, incidental diagnosis, and in later gestations. US abnormalities were more likely to be associated with a full 45,X karyotype. CONCLUSION: There was an evolution in the way genetic counseling was performed following prenatal diagnosis of Turner syndrome that coincided with the opening of MCPDs in France. This resulted in a decrease in the rate of termination of affected fetuses.


Assuntos
Aborto Induzido/estatística & dados numéricos , Síndrome de Turner/diagnóstico por imagem , Adulto , Feminino , França/epidemiologia , Aconselhamento Genético/organização & administração , Humanos , Cariotipagem/estatística & dados numéricos , Medição da Translucência Nucal , Gravidez , Resultado da Gravidez , Estudos Retrospectivos
15.
Biochim Biophys Acta ; 1818(7): 1682-90, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22406554

RESUMO

Active Na+ absorption by alveolar ENaC is the main driving force of liquid clearance at birth and lung edema resorption in adulthood. We have demonstrated previously that long-term modulation of KvLQT1 and KATP K+ channel activities exerts sustained control in Na+ transport through the regulation of ENaC expression in primary alveolar type II (ATII) cells. The goal of the present study was: 1) to investigate the role of the alpha-ENaC promoter, transfected in the A549 alveolar cell line, in the regulation of ENaC expression by K+ channels, and 2) to determine the physiological impact of K+ channels and ENaC modulation on fluid clearance in ATII cells. KvLQT1 and KATP channels were first identified in A549 cells by PCR and Western blotting. We showed, for the first time, that KvLQT1 activation by R-L3 (applied for 24 h) increased alpha-ENaC expression, similarly to KATP activation by pinacidil. Conversely, pharmacological KvLQT1 and KATP inhibition or silencing with siRNAs down-regulated alpha-ENaC expression. Furthermore, K+ channel blockers significantly decreased alpha-ENaC promoter activity. Our results indicated that this decrease in promoter activity could be mediated, at least in part, by the repressor activity of ERK1/2. Conversely, KvLQT1 and KATP activation dose-dependently enhanced alpha-ENaC promoter activity. Finally, we noted a physiological impact of changes in K+ channel functions on ERK activity, alpha-, beta-, gamma-ENaC subunit expression and fluid absorption through polarized ATII cells. In summary, our results disclose that K+ channels regulate alpha-ENaC expression by controlling its promoter activity and thus affect the alveolar function of fluid clearance.


Assuntos
Células Epiteliais/metabolismo , Canais Epiteliais de Sódio/genética , Canais KATP/genética , Canal de Potássio KCNQ1/genética , Regiões Promotoras Genéticas/genética , Benzodiazepinas/farmacologia , Transporte Biológico/efeitos dos fármacos , Western Blotting , Linhagem Celular Tumoral , Células Epiteliais/patologia , Canais Epiteliais de Sódio/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glibureto/farmacologia , Humanos , Canais KATP/metabolismo , Canal de Potássio KCNQ1/metabolismo , Moduladores de Transporte de Membrana/farmacologia , Pinacidil/farmacologia , Bloqueadores dos Canais de Potássio/farmacologia , Alvéolos Pulmonares/metabolismo , Alvéolos Pulmonares/patologia , Compostos de Amônio Quaternário/farmacologia , Interferência de RNA , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sódio/metabolismo
16.
Surg Radiol Anat ; 19(1): 23-30, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9060113

RESUMO

The deformations and stresses acting on the acetabular rim have not been very precisely documented. The authors present a study based on an experimental simulation of hip loading with anatomic correlations. 122 dissections were performed in order to define the anatomic aspect of the roof (and especially of Byers's "area 17") and the intermediate area between the anterior and posterior acetabular cornua. Ten fresh cadavers were tested on the lines of previous studies on monopodal or bipodal loading. An extensometric study was performed with special attention to the transverse acetabular ligament, supra-acetabular area and obturator foramen. The area 17 of Byers is a transitional zone and the mobility of the posterior cornu is 3 times that of the anterior cornu. Resection of the acetabular ligament modifies the displacement of the posterior cornu under loading but has no influence on deformation of the oburator foramen. The biomechanical behavior of the acetabular roof in the standing position is influenced by the conditions of monopodal or bipodal loading and by femoral rotation, but a tendency to extrusion was constantly noted.


Assuntos
Acetábulo/anatomia & histologia , Acetábulo/fisiologia , Fenômenos Biomecânicos , Feminino , Humanos , Ligamentos/anatomia & histologia , Masculino , Pessoa de Meia-Idade , Suporte de Carga/fisiologia
17.
Eur Spine J ; 6(4): 222-32, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9294745

RESUMO

Corrective surgery for kyphotic deformities of the spine in ankylosing spondylitis is a major surgery for rare indications. The authors report 31 lumbar osteotomies. The goal is to correct the deformity through a posterior limited approach and to minimise the neurological risks. The modifications developed by the authors for monosegmental closing wedge osteotomies are explained. The posterior resection is rhomboid shaped with a bilateral lamina removal. An osteotomy is performed in a forwards direction on the lateral aspects of the vertebral body without bone resection. This osteoclasty allows progressive vertebral body compression. Pediclectomy is associated if the corresponding foramen at the osteotomy level becomes too narrow in the process of redressing the spine. The resection level is adjusted so that superior and inferior posterior arches come into contact with a good compression. The authors point out the risk of lateral translation. Before the osteotomy, the two adjacent vertebrae are implanted with 5-mm cylindrical pedicular screws, so that posterior fixation can be carried out at any time. Posterior monobloc fixation allows for very great compression of the osteoclasty. The authors compare the results of their experiences in opening and closing osteotomy. They progressively changed their technique for closing osteotomies, because of published vascular complications and mechanical risks (instability and pseudarthrosis in opening osteotomies). Closing osteotomy also minimises the risk of stenosis with radicular compression or traction if an important correction is performed. The level of the osteotomy varied in this series, which had a correction rate of up to 75 degrees. The choice of level depends on secondary effects on pelvic position and projection of the centre of gravity. The preferred procedure remains a monosegmental correction because it is faster and easier, with minimum bleeding. Short monobloc posterior fixation is sufficient to maintain reduction and to obtain stability from posterior compression.


Assuntos
Cifose/etiologia , Cifose/cirurgia , Vértebras Lombares/cirurgia , Osteotomia , Espondilite Anquilosante/complicações , Adulto , Feminino , Humanos , Complicações Intraoperatórias , Cifose/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Dispositivos de Fixação Ortopédica , Complicações Pós-Operatórias , Radiografia , Resultado do Tratamento
18.
Artigo em Francês | MEDLINE | ID: mdl-9097854

RESUMO

PURPOSE OF THE STUDY: The goal of this study was to precise indications and surgical techniques for stabilisation with or without decompression of the upper cervical spine instability in rheumatoid arthritis. MATERIAL AND METHODS: 28 patients presenting upper cervical spine disease have been reviewed (mean age 57 years). These patients had been suffering from severe diffuse arthritis during an average of 14.5 years. The anterior atlanto-axial dislocation was most frequent (25 times), 1 posterior dislocation and 2 vertical dislocations. Odontoid lysis was noted 19 times. A subluxation of the lower cervical spine was present in 12 patients. SURGICAL TECHNIQUE: C1-C2 arthrodesis was performed 12 times (9 times with a loop wire and 3 isthmo-pedicular screws C2-C1), occipito-cervical arthrodesis with plates 16 times. Operative traction was necessary 5 times. The associated surgical gestures included 3 times a laminectomy, 2 times an enlargement of the occipital foramen, 1 section of the Arnold nerve. In 2 patients was associated a fixation of the lower cervical spine. RESULTS: With an average of 27 months follow-up, functional results (classified according to Ranawat's criteria) were satisfactory in 14 patients, improved in 7 patients, unchanged in 4 and bad in 3. The reduction of the anterior displacement in 25 patients was complete 11 times, partial 17 times and null 3 times. The reduction of the vertical displacement was complete once, partial 3 times. Arthrodesis fusion was obtained in 19 cases, 5 times it was a fibrous union and 4 pseudarthrosis occurred, all with C1-C2 loop wire. The rate of complications was high: 2 infections on bone site grafting requiring reoperation, 2 infections with secondary septicemia after lack of reduction. DISCUSSION AND CONCLUSION: Occipito-cervical arthrodesis is necessary as soon as the patient presents neurological signs. When there is an anterior dislocation associated with vertical dislocation, if there is posterior dislocation in case of osteoporosis of the posterior C1-C2 arc, or destabilisation of the lower cervical spine. C1-C2 arthrodesis is suggested when there is no important neurological signs, when displacement is limited to a pure anterior dislocation and in young patient with good bone quality.


Assuntos
Artrite Reumatoide/cirurgia , Vértebras Cervicais , Luxações Articulares/cirurgia , Instabilidade Articular/cirurgia , Fusão Vertebral/métodos , Adulto , Idoso , Artrite Reumatoide/complicações , Articulação Atlantoaxial , Vértebras Cervicais/diagnóstico por imagem , Vértebras Cervicais/cirurgia , Feminino , Humanos , Luxações Articulares/etiologia , Instabilidade Articular/etiologia , Masculino , Pessoa de Meia-Idade , Exame Neurológico , Medição da Dor , Prognóstico , Radiografia , Estudos Retrospectivos
19.
Chirurgie ; 121(8): 597-600, 1996.
Artigo em Francês | MEDLINE | ID: mdl-9091274

RESUMO

Post-operative spine displacement occurs by excessive or aggravated vertebral sliding. Sex and age, anatomics factors (pre-operative displacement, intersomatic discs quality, hyperlordosis) and operative factors (extensive laminectomy, artherectomy) are predisposing factors. The risk of post-operative vertebral displacement is calculated by a fine pre and per-operative analysis of these pre-disposing factors: Tolerance to post-operative spinal displacement cannot be foreseen and surgical recovery may be difficult whenever.


Assuntos
Deslocamento do Disco Intervertebral/etiologia , Complicações Pós-Operatórias , Fusão Vertebral , Estenose Espinal/cirurgia , Feminino , Humanos , Deslocamento do Disco Intervertebral/cirurgia , Masculino , Fatores de Risco , Fatores de Tempo
20.
Chirurgie ; 121(8): 609-15, 1996.
Artigo em Francês | MEDLINE | ID: mdl-9091276

RESUMO

From 1981 to 1994, 16 patients with 18 thoracic disk hernias due to degenerative disease (n = 13), trauma (n = 4) or Scheuermann's disease (n = 1) received surgical treatment. Most were situated from T6 to T12. There were 10 medial hernias and 8 lateral hernias. Symptom duration was a mean 23 months at surgery including spinal pain (n = 13) and spinal syndrome (n = 9). Posterolateral access was used in 13 cases and the anterior route in 2, both requiring a graft. After a follow-up of 5 years 1 month, functional and subjective results were excellent or good in 83% of the cases, acceptable in 6% and poor in 11%. Two failures with the posterolateral route corresponded to one patient with initial trauma-induced paraplegia and another with neurological aggravation after the first laminectomy. In our experience, the posteriolateral route is preferred to allow good visual control even in cases involving several levels. Secondary laminectomy may be performed without risking displacement. The presence of the Adamkiewicz artery on the same side and at the same level dictates use of the anterior route which may soon be replaced by video-assisted thoracoscopy to avoid resection of the rib.


Assuntos
Deslocamento do Disco Intervertebral/cirurgia , Vértebras Torácicas , Humanos , Deslocamento do Disco Intervertebral/diagnóstico , Métodos , Estudos Retrospectivos , Fatores de Tempo
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