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1.
R Soc Open Sci ; 4(3): 170117, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28405407

RESUMO

How do invasive pests affect interactions between members of pre-existing agrosystems? The invasive pest Drosophila suzukii is suspected to be involved in the aetiology of sour rot, a grapevine disease that otherwise develops following Drosophila melanogaster infestation of wounded berries. We combined field observations with laboratory assays to disentangle the relative roles of both Drosophila in disease development. We observed the emergence of numerous D. suzukii, but no D. melanogaster flies, from bunches that started showing mild sour rot symptoms days after field collection. However, bunches that already showed severe rot symptoms in the field mostly contained D. melanogaster. In the laboratory, oviposition by D. suzukii triggered sour rot development. An independent assay showed the disease increased grape attractiveness to ovipositing D. melanogaster females. Our results suggest that in invaded vineyards, D. suzukii facilitates D. melanogaster infestation and, consequently, favours sour rot outbreaks. Rather than competing with close species, the invader subsequently permits their reproduction in otherwise non-accessible resources and may cause more frequent, or more extensive, disease outbreaks.

2.
Mol Ecol ; 24(24): 6107-19, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26562076

RESUMO

Unravelling variation among taxonomic orders regarding the rate of evolution in microsatellites is crucial for evolutionary biology and population genetics research. The mean mutation rate of microsatellites tends to be lower in arthropods than in vertebrates, but data are scarce and mostly concern accumulation of mutations in model species. Based on parent-offspring segregations and a hierarchical Bayesian model, the mean rate of mutation in the orthopteran insect Schistocerca gregaria was estimated at 2.1e(-4) per generation per untranscribed dinucleotide locus. This is close to vertebrate estimates and one order of magnitude higher than estimates from species of other arthropod orders, such as Drosophila melanogaster and Daphnia pulex. We also found evidence of a directional bias towards expansions even for long alleles and exceptionally large ranges of allele sizes. Finally, at transcribed microsatellites, the mean rate of mutation was half the rate found at untranscribed loci and the mutational model deviated from that usually considered, with most mutations involving multistep changes that avoid disrupting the reading frame. Our direct estimates of mutation rate were discussed in the light of peculiar biological and genomic features of S. gregaria, including specificities in mismatch repair and the dependence of its activity to allele length. Shedding new light on the mutational dynamics of grasshopper microsatellites is of critical importance for a number of research fields. As an illustration, we showed how our findings improve microsatellite application in population genetics, by obtaining a more precise estimation of S. gregaria effective population size from a published data set based on the same microsatellites.


Assuntos
Evolução Molecular , Mutação em Linhagem Germinativa , Gafanhotos/genética , Repetições de Microssatélites , Taxa de Mutação , Alelos , Animais , Teorema de Bayes , Feminino , Genética Populacional , Genótipo , Masculino , Densidade Demográfica , Análise de Sequência de DNA
3.
Orthop Traumatol Surg Res ; 100(6 Suppl): S339-47, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25217030

RESUMO

A prospective multi-centre nationwide study of patients with congenital dislocation of the hip (CDH) diagnosed after 3 months of age was conducted with support from the French Society for Paediatric Orthopaedics (Société Française d'Orthopédie Pédiatrique [SoFOP]), French Organisation for Outpatient Paediatrics (Association Française de Pédiatrie Ambulatoire [AFPA]), and French-Speaking Society for Paediatric and Pre-Natal Imaging (Société Francophone d'Imagerie Pédiatrique et Prénatale [SFIPP]). The results showed inadequacies in clinical screening for CDH that were patent when assessed quantitatively and probably also present qualitatively. These findings indicate a need for a communication and educational campaign aimed at highlighting good clinical practice guidelines in the field of CDH screening. The usefulness of routine ultrasound screening has not been established. The findings from this study have been used by the authors and French National Health Authority (Haute Autorité de Santé [HAS]) to develop recommendations about CDH screening. There is an urgent need for a prospective randomised multi-centre nationwide study, which should involve primary-care physicians.


Assuntos
Diagnóstico por Imagem/métodos , Luxação Congênita de Quadril/diagnóstico , Programas de Rastreamento/métodos , Criança , Pré-Escolar , Feminino , França/epidemiologia , Luxação Congênita de Quadril/epidemiologia , Articulação do Quadril/diagnóstico por imagem , Humanos , Lactente , Masculino , Estudos Prospectivos , Radiografia , Inquéritos e Questionários , Ultrassonografia
4.
Orthop Traumatol Surg Res ; 99(7): 881-5, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24070693

RESUMO

Hereditary sensory and autonomic neuropathy type IV (HSAN-IV) is a very rare autosomal recessive disorder characterized by recurrent episodes of unexplained fever, extensive anhidrosis, total insensitivity to pain, hypotonia, and mental retardation. The most frequent complications of this disease are corneal scarring, multiple fractures, joint deformities, osteomyelitis, and disabling self-mutilations. We reported the case of a 12-year-old boy. The goal was to discuss our decision-making and compare this case with cases described in the literature.


Assuntos
Neuropatias Hereditárias Sensoriais e Autônomas/complicações , Osteomielite/etiologia , Tíbia , Fraturas da Tíbia/etiologia , Criança , Humanos , Masculino , Osteomielite/diagnóstico por imagem , Radiografia , Fraturas da Tíbia/diagnóstico por imagem
5.
Orthop Traumatol Surg Res ; 99(4): 433-9, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23623317

RESUMO

BACKGROUND: Many surgical procedures for hallux valgus correction have been reported, including percutaneous techniques. In children, the risk of recurrent hallux valgus after any type of surgical correction seems to deserve attention. To our knowledge, no studies have investigated the outcomes of percutaneous hallux valgus surgery in children. Here, we report a study on this topic. MATERIALS AND METHODS: We retrospectively reviewed 33 percutaneous surgical procedures to correct idiopathic hallux valgus in 18 children younger than 16 years of age. Radiographs obtained pre-operatively and at last follow-up were used to determine the hallux valgus angle (HVA), intermetatarsal angle (IMA), and distal metatarsal articular angle (DMAA). Clinical outcomes were assessed using the American Orthopaedic Foot and Ankle Society (AOFAS) score and a satisfaction score. RESULTS: Mean follow-up was 30 months. At surgery, mean age was 12.5 years and the growth plates were open in 20/33 (61%) cases. Mean HVA correction was 8.6° (from 28.06° to 19.45°, P<0.01) and mean DMAA correction was 7° (from 15.97° to 8.97°, P<0.01). At last follow-up, 20 (61%) feet had HVA values greater than 16°, but in half these cases the patients reported being satisfied with the procedure, leaving 30% of feet with symptomatic under-correction. Mean post-operative AOFAS score was 80.7. Patients were satisfied or very satisfied for 24/33 (73%) feet. DISCUSSION: We found a high-rate of radiographic under-correction. Studies of factors associated with recurrent hallux valgus would be expected to result in technical improvements and therefore in better outcomes. CONCLUSION: Our evaluation of short-term outcomes after percutaneous hallux valgus surgery without internal fixation showed both a high-rate of under-correction and a high-rate of patient satisfaction. Medium-term studies are needed to determine whether these results are sustained over time. The available data suggest a number of technical improvements. At present, we plan to continue to offer this procedure to children and their families. LEVEL OF EVIDENCE: Level IV, retrospective study.


Assuntos
Hallux Valgus/cirurgia , Articulação Metatarsofalângica/cirurgia , Osteotomia/métodos , Satisfação do Paciente , Adolescente , Criança , Feminino , Seguimentos , Hallux Valgus/diagnóstico por imagem , Hallux Valgus/fisiopatologia , Humanos , Articulação Metatarsofalângica/diagnóstico por imagem , Articulação Metatarsofalângica/fisiopatologia , Radiografia , Amplitude de Movimento Articular , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento
6.
Arch Pediatr ; 20(1): 30-2, 2013 Jan.
Artigo em Francês | MEDLINE | ID: mdl-23266168

RESUMO

Thoracic outlet syndrome (TOS) is a rare pediatric syndrome and few cases have been reported in the literature. The authors report the case of a 10-year-old boy with generalized arm pain and neck stiffness. The angiocomputed tomography revealed the presence of a TOS caused by an additional cervical rib and stenosis of the sub-clavian artery. The resection of this rib relieved the patient of his pain during a full year following surgery. This case reminds us that children can also be affected by TOS. When a cervical rib causes TOS, a resection is often necessary.


Assuntos
Síndrome da Costela Cervical/diagnóstico por imagem , Costela Cervical/anormalidades , Angiografia , Braço , Síndrome da Costela Cervical/etiologia , Síndrome da Costela Cervical/cirurgia , Criança , Humanos , Masculino , Pescoço , Dor/etiologia , Parestesia/etiologia , Doenças Raras , Tomografia Computadorizada por Raios X , Resultado do Tratamento
7.
Eur Radiol ; 23(3): 836-44, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23080071

RESUMO

OBJECTIVES: To propose an easy and reproducible sonographic screening test able to avoid late presentation of developmental dysplasia of the hip (DDH). METHODS: The pubo-femoral distance (PFD) cut-off point was determined on 980 infants who underwent ultrasonography of the hips in comparison with the final diagnosis, based on clinical, ultrasound data and follow-up. PFD reproducibility was tested on 52 hips by both an experienced and an inexperienced radiologist. After teaching this screening method to general radiologists, its impact was evaluated by analysing the rate of late diagnosis in an entire administrative area. RESULTS: An abnormal PFD threshold above 6 mm gave a sensitivity of 97.4 % for the diagnosis of DDH (271 hips) and a specificity of 84 %. Sensitivity increased to 100 % when taking into consideration children of 1 month or older. The PFD measurement stayed reproducible even in inexperienced hands (k = 0.795). For 3 years, following the extension of screening to all female infants, there was no late diagnosis of DDH in girls in amongst a catchment area of 1 million inhabitants. CONCLUSIONS: PFD measurement with a threshold for abnormality of 6 mm at the age of 1 month, without asymmetry above 1.5 mm, could eradicate DDH late diagnosis.


Assuntos
Algoritmos , Pontos de Referência Anatômicos/diagnóstico por imagem , Diagnóstico Tardio/prevenção & controle , Fêmur/diagnóstico por imagem , Luxação Congênita de Quadril/diagnóstico por imagem , Interpretação de Imagem Assistida por Computador/métodos , Osso Púbico/diagnóstico por imagem , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Programas de Rastreamento/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Ultrassonografia
8.
Orthop Traumatol Surg Res ; 98(4 Suppl): S73-6, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22591785

RESUMO

The Ponseti method applied to treating idiopathic club foot consists in placing successive corrective casts, possibly an Achilles tendon tenotomy, then derotation braces, a method that has proven its efficacy. This study compared 221 cases of club foot treated with this method between 2002 and 2007 divided into two groups, based on whether or not Achilles tendon tenotomy was performed. Assessment was both clinical and sonographic. We observed clear improvement of the results in the group that underwent Achilles tendon tenotomy and a significant difference in the rate of secondary surgery. The sonographic evaluation also showed improvement of the morphological results. We now systematically propose Achilles tendon tenotomy however severe club foot may be.


Assuntos
Pé Torto Equinovaro/terapia , Tendão do Calcâneo/diagnóstico por imagem , Tendão do Calcâneo/cirurgia , Moldes Cirúrgicos , Pé Torto Equinovaro/diagnóstico por imagem , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Manipulação Ortopédica/métodos , Estudos Retrospectivos , Tenotomia/métodos , Resultado do Tratamento , Ultrassonografia
9.
Orthop Traumatol Surg Res ; 97(8): 874-6, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22112462

RESUMO

Among the congenital anomalies involving the lateral compartment of the knee, the combination of both a discoid meniscus and agenesis of the anterior cruciate ligament (ACL) is extremely rare and probably underestimated due to the presence of a meniscofemoral ligament often mistaken for an intact ACL. The therapeutic management of such abnormalities is not univocal and highly depends on their clinical impact. We report on the observations of an 8-year-old boy presenting with a cystic formation on a lateral discoid meniscus associated with agenesis of the ACL and the presence of an anterior lateral meniscofemoral ligament.


Assuntos
Artroscopia/métodos , Doenças do Desenvolvimento Ósseo/diagnóstico , Doenças das Cartilagens/diagnóstico , Artropatias/diagnóstico , Articulação do Joelho/anormalidades , Meniscos Tibiais/anormalidades , Doenças do Desenvolvimento Ósseo/congênito , Doenças das Cartilagens/congênito , Criança , Diagnóstico Diferencial , Seguimentos , Humanos , Artropatias/congênito , Imageamento por Ressonância Magnética , Masculino
10.
Orthop Traumatol Surg Res ; 97(6): 629-33, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21924969

RESUMO

INTRODUCTION: Irreducible developmental dysplasia of the hip (DDH) in newborns is a rare entity. The different obstacles preventing reduction have been described in the literature. HYPOTHESIS: A clinical form of DDH with hypertrophy of the cartilage of the acetabular roof (acetabular bulge) can be reliably identified on ultrasound and should probably be defined as a separate entity. MATERIALS AND METHODS: For the first time, the authors report their experience, a review of the literature and the radiographic description (ultrasound, arthrography MRI) of irreducible neonatal DDH due to hypertrophy of the cartilage of the acetabular roof (acetabular bulge) in 12 infants (15 hips). RESULTS: Neonatal sonography seems to be sufficient to identify this specific clinical entity without any additional work-up. This sonographic sign could help determine the therapeutic strategy earlier in this severe and complex form of DDH.


Assuntos
Luxação Congênita de Quadril/diagnóstico por imagem , Luxação Congênita de Quadril/etiologia , Acetábulo , Cartilagem/patologia , Feminino , Humanos , Hipertrofia/complicações , Hipertrofia/diagnóstico por imagem , Lactente , Recém-Nascido , Masculino , Estudos Retrospectivos , Ultrassonografia
11.
J Radiol ; 92(6): 481-93, 2011 Jun.
Artigo em Francês | MEDLINE | ID: mdl-21704244

RESUMO

At one month, the acetabular depth from a standard lateral coronal section is 4.6 ± 1.0mm. The correlation between experienced and junior radiologists is high (kappa 0.795). A treshhold of 6mm with a Δ (difference between right and left) less than 1.5mm provides a sensitivity of 100% for the detection of DDH at one month. Universal US screening at one month of all high-risk infants in 2009 resulted in a reduction of delayed diagnosis of DDH (zero girls, two boys) in Ille-et-Vilaine due to continuous medical education of general radiologists.


Assuntos
Luxação Congênita de Quadril/diagnóstico por imagem , Árvores de Decisões , Feminino , Humanos , Recém-Nascido , Masculino , Triagem Neonatal/métodos , Ultrassonografia
12.
Bull Entomol Res ; 100(1): 9-17, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19413914

RESUMO

Parental environments could play an important role in controlling insect outbreaks, provided they influence changes in physiological, developmental or behavioural life-history traits related to fluctuations in population density. However, the potential implication of parental influence in density-related changes in life-history traits remains unclear in many insects that exhibit fluctuating population dynamics, particularly locusts. In this study, we report a laboratory experiment, which enabled us to characterize the life-history trait modifications induced by parental crowding of female individuals from a frequently outbreaking population of Locusta migratoria (Linnaeus) (Orthoptera: Acrididae). We found that a rearing history of crowding led to reduced female oviposition times and increased offspring size but did not affect the developmental time, survival, fecundity, and the sex-ratio and the number of offspring. Because all studied females were raised in a common environment (isolation conditions), these observed reproductive differences are due to trans-generational effects induced by density. We discuss the ecological and evolutionary implications of the observed density-dependent parental effects on the life-history of L. migratoria.


Assuntos
Comportamento Animal/fisiologia , Aglomeração , Locusta migratoria/fisiologia , Oviposição/fisiologia , Animais , Tamanho Corporal/fisiologia , Feminino , Fertilidade/fisiologia , Razão de Masculinidade
13.
Mol Ecol ; 17(16): 3640-53, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18643881

RESUMO

An understanding of the role of factors intrinsic to a species' life history in structuring contemporary genetic variation is a fundamental, but understudied, aspect of evolutionary biology. Here, we assessed the influence of the propensity to outbreak in shaping worldwide genetic variation in Locusta migratoria, a cosmopolitan pest well known for its expression of density-dependent phase polyphenism. We scored 14 microsatellites in nine subspecies from 25 populations distributed over most of the species' range in regions that vary in the historical frequency and extent of their outbreaks. We rejected the hypothesis that L. migratoria consists of two genetically distinct clusters adapted to habitats either rarely (nonoutbreaking) or cyclically (outbreaking) favourable to increases in population density. We also invalidated the current subspecific taxonomic classification based on morphometrics. Bayesian inferences indicated evidence of a homogenizing effect of outbreaks on L. migratoria population structure. Geographical and ecological barriers to gene flow in conjunction with historical events can also explain the observed patterns. By systematically assessing the effects of null alleles using computer simulations, we also provide a template for the analysis of microsatellite data sets characterized by a high prevalence of null alleles.


Assuntos
Genes de Insetos , Genética Populacional , Locusta migratoria/genética , Alelos , Animais , Evolução Molecular , Fluxo Gênico , Variação Genética , Genótipo , Geografia , Repetições de Microssatélites , Modelos Genéticos , Dinâmica Populacional
14.
Mol Ecol ; 16(15): 3069-83, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17651188

RESUMO

Drosophila subobscura is a Palearctic species that was first observed in South and North America in the early 1980s, and that rapidly invaded broad latitudinal ranges on both continents. To trace the source and history of this invasion, we obtained genotypic data on nine microsatellite loci from two South American, two North American and five European populations of D. subobscura. We analysed these data with traditional statistics as well as with an approximate Bayesian computation (ABC) framework. ABC methods yielded the strongest support for the scenario involving a serial introduction with founder events from Europe into South America, and then from South America into North America. Stable effective population size of the source population was very large (around one million individuals), and the propagule size was notably smaller for the introduction into South America (i.e. high bottleneck severity index with only a few effective founders) but considerably larger for the subsequent introduction into North America (i.e. low bottleneck severity index with around 100-150 effective founders). Finally, the Mediterranean region of Europe (and most likely Barcelona from the localities so far analysed) is proposed as the source of the New World flies, based on mean individual assignment statistics.


Assuntos
Drosophila/genética , Repetições de Microssatélites , Migração Animal , Animais , Teorema de Bayes , Evolução Biológica , Drosophila/classificação , Drosophila/fisiologia , Europa (Continente) , Variação Genética , Genótipo , Filogenia
15.
Rev Chir Orthop Reparatrice Appar Mot ; 90(7): 666-9, 2004 Nov.
Artigo em Francês | MEDLINE | ID: mdl-15625518

RESUMO

A thirteen-year-old child underwent surgery for posttraumatic nonunion of the clavicle. This complication, which is uncommon in adults and exceptional in children, occurred after three fractures of the left clavicle. The diagnosis can be retained after ruling out congenital nonunion of the clavicle. Surgery can be proposed if functional impairment persists for at least one year. For children, the preferred technique is osteosynthesis with centromedullary pinning and bone graft. While surveillance may not be necessary for a unique fracture of the clavicle, prolonged surveillance appears to be necessary in patients who sustain repeated fractures of the clavicle.


Assuntos
Clavícula/lesões , Fraturas não Consolidadas , Pré-Escolar , Clavícula/cirurgia , Feminino , Fraturas não Consolidadas/cirurgia , Humanos
16.
Rev Chir Orthop Reparatrice Appar Mot ; 87(8): 830-4, 2001 Dec.
Artigo em Francês | MEDLINE | ID: mdl-11845088

RESUMO

Compression of the cervical spinal cord developed six months after the first signs of a stiff and painful spine in an 11-year-old girl. The clinical course, the association with other skeletal localization, particularly the sacroiliac joint and the roof of the acetabulum and the pathology findings of nonspecific inflammation led to the diagnosis of chronic recurrent multifocal osteomyelitis that can be included in a SAPHO syndrome (synovitis-acne-pustulosis- hyperostosis-osteitis). We report the specific findings in our case and review the literature to define the nosology framework of this rather uncommon condition. To our knowledge, this is the first report of spinal cord injury in a child related to SAPHO syndrome.


Assuntos
Síndrome de Hiperostose Adquirida/complicações , Cervicalgia/etiologia , Osteomielite/etiologia , Compressão da Medula Espinal/etiologia , Dor nas Costas/etiologia , Vértebras Cervicais/diagnóstico por imagem , Criança , Doença Crônica , Feminino , Seguimentos , Humanos , Imageamento por Ressonância Magnética , Cervicalgia/diagnóstico por imagem , Radiografia , Recidiva , Compressão da Medula Espinal/diagnóstico , Compressão da Medula Espinal/diagnóstico por imagem , Fusão Vertebral , Fatores de Tempo
17.
Eur Respir J ; 15(2): 326-31, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10706500

RESUMO

The aim of this study was to examine risk factors for and causes of mortality in patients with obstructive sleep apnoea syndrome (OSAS) treated by nasal continuous positive airway pressure (CPAP). Univariate and multivariate analyses of the data on patients registered in the Association Nationale pour le Traitement A Domicile de l'Insuffisance Respiratoire chronique (ANTADIR) Observatory between January 1, 1985 and December 31, 1993 and followed to January 1, 1996. Survival ratios were compared to those of the French population. A case control study compared patients who died with patients of the same age and sex, in the same Regional Association, who were equipped with CPAP at the same time. Five-thousand-six-hundred-and-sixty-nine patients had CPAP treatment. Two-hundred-and-seventy-six had died. One-hundred-and-twenty-four deaths were examined and compared to 123 control subjects. Overall mortality was the same as the general French population. Independent risk factors for death were age, oxygen tension in arterial blood (Pa,O2) and forced expiratory volume in one second (FEV1) (per cent predicted). In the case-control study independent risk factors for death in the past history were cardiac arrhythmia with an odds ratio (OR) of 2.8 (95% confidence interval (CI) 1.1-7.2), respiratory disorders (OR 2.8; CI 1.6-4.9) ischaemic events (OR 2.2; CI 1.2-4.2), neurological and psychiatric disorders (OR 2.4; CI 1.1-5.4). A significant excess of cardiovascular deaths and an excess of deaths from accidents and poisonings was found. In conclusion, patients die on therapy predominantly from cardiovascular causes but many have a past history of cardiovascular conditions. Compliance with treatment may be important for survival. Continuous positive airway pressure is an effective therapy for obstructive sleep apnoea syndrome but older patients with reduced spirometry and hypoxaemia may need more attention paid to these aspects of their condition.


Assuntos
Respiração com Pressão Positiva/métodos , Síndromes da Apneia do Sono/mortalidade , Síndromes da Apneia do Sono/terapia , Doenças Cardiovasculares/epidemiologia , Estudos de Casos e Controles , Causas de Morte , Feminino , Serviços de Assistência Domiciliar , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Multicêntricos como Assunto , Modelos de Riscos Proporcionais , Sistema de Registros , Fatores de Risco , Análise de Sobrevida
18.
Heredity (Edinb) ; 82 (Pt 5): 473-8, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10383666

RESUMO

Sex allocation data in eusocial Hymenoptera (ants, bees and wasps) provide an excellent opportunity to assess the effectiveness of kin selection, because queens and workers differ in their relatedness to females and males. The first studies on sex allocation in eusocial Hymenoptera compared population sex investment ratios across species. Female-biased investment in monogyne (= with single-queen colonies) populations of ants suggested that workers manipulate sex allocation according to their higher relatedness to females than males (relatedness asymmetry). However, several factors may confound these comparisons across species. First, variation in relatedness asymmetry is typically associated with major changes in breeding system and life history that may also affect sex allocation. Secondly, the relative cost of females and males is difficult to estimate across sexually dimorphic taxa, such as ants. Thirdly, each species in the comparison may not represent an independent data point, because of phylogenetic relationships among species. Recently, stronger evidence that workers control sex allocation has been provided by intraspecific studies of sex ratio variation across colonies. In several species of eusocial Hymenoptera, colonies with high relatedness asymmetry produced mostly females, in contrast to colonies with low relatedness asymmetry which produced mostly males. Additional signs of worker control were found by investigating proximate mechanisms of sex ratio manipulation in ants and wasps. However, worker control is not always effective, and further manipulative experiments will be needed to disentangle the multiple evolutionary factors and processes affecting sex allocation in eusocial Hymenoptera.

19.
Arch Pediatr ; 5(7): 754-7, 1998 Jul.
Artigo em Francês | MEDLINE | ID: mdl-9759275

RESUMO

UNLABELLED: Varicella is a common viral infection which is generally benign in infancy and has a good outcome. It may sometimes be complicated by severe group A streptococcal superinfection. CASE REPORT: Three days after the beginning of varicella, a previously healthy 2-year-old girl presented with left leg pain, lameness and edema of all four limbs. Toxic shock syndrome occurred, due to beta-hemolytic group A Streptococcus grown from blood culture. Computerized tomography (CT) scan showed a mild effusion involving both hips. Cefotaxim was administered, but the week after magnetic resonance imaging (MRI) showed a necrotizing fasciitis and a lesion of the left leg leading to a patchy femoral diaphysis consistent with osteomyelitis. Joint aspirate culture did not grow. The left leg was immobilized in plaster for 6 weeks and the child was given cefotaxim and fosfomycin parenterally during 30 days, then followed by 45 days of oral amoxicillin. She recovered without sequelae. CONCLUSION: Group A Streptococcus infection is a dangerous complication of varicella. It must be considered in case of any joint pain occurring during or just after this disease. The choice of the best treatment needs full collaboration between surgeons, radiologists and pediatricians.


Assuntos
Varicela/complicações , Choque Séptico/complicações , Infecções Estreptocócicas/complicações , Streptococcus pyogenes , Cefotaxima/uso terapêutico , Pré-Escolar , Quimioterapia Combinada/uso terapêutico , Feminino , Fosfomicina/uso terapêutico , Humanos , Choque Séptico/tratamento farmacológico , Infecções Estreptocócicas/tratamento farmacológico
20.
Rev Chir Orthop Reparatrice Appar Mot ; 84(7): 617-22, 1998 Nov.
Artigo em Francês | MEDLINE | ID: mdl-9881407

RESUMO

PURPOSE: The purpose of this study was double. We evaluated long term results in 30 patients who had in situ pinning fixation. We tried to assess the advantage of pinning versus screw fixation. MATERIAL AND METHODS: We reviewed retrospectively 30 cases treated for SCFE by in situ pinning fixation. Between august 1985 and may 1995, 33 hips were treated (3 bilateral cases). The age averaged 10 years and 3 months. Twenty-one cases were chronic (64 per cent), 8 cases were acute forms (21 per cent) and 4 acute cases revealed progressive cases (14 per cent). There were 19 boys and 11 girls. The osteosynthesis was made with 3 pins (except in 4 cases with only 2 pins). RESULTS: The follow-up ranged from 20 to 50 months (average 35 months). The upper femoral growth plate was closed at an average of 16 months after surgery (6 months to 21 months). Three prophylactic controlateral fixations were performed before our protocola was established. No pin penetration was noted. No chondrolysis or avascular necrosis was noted. Complications were: 2 superficial hematomas with spontaneous resorption, 1 lateral pin migration without consequence on fixation, 1 break-pin in soft tissue without clinical consequence. The main complication was, in one case, a secondary slipping of the epiphysis after premature pin removal. Hip function was normal except in 2 cases with loss of motion in internal rotation. DISCUSSION: Stiffness of the screw is the most important advantage. A single screw seems to be enough. Removal of the screw is difficult, sometimes impossible. CONCLUSION: Percutaneous in situ pinning in SCFE is recommended. It is an easy surgical technique with an absence of complication such as chondrolysis or avascular necrosis in our experience. It is also the easiest method for hardware removal.


Assuntos
Pinos Ortopédicos , Parafusos Ósseos , Epifise Deslocada/cirurgia , Cabeça do Fêmur , Doença Aguda , Adolescente , Criança , Doença Crônica , Progressão da Doença , Epifise Deslocada/diagnóstico por imagem , Epifise Deslocada/fisiopatologia , Feminino , Humanos , Masculino , Radiografia , Amplitude de Movimento Articular , Recidiva , Estudos Retrospectivos , Resultado do Tratamento
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