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1.
Int J Sports Med ; 38(1): 71-75, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27737484

RESUMO

A new concussion interchange rule (CIR) was introduced in 2014 for the National Rugby League and National Youth Competition (NYC). The CIR allows a player suspected of having sustained a concussion to be removed from play and assessed without an interchange being tallied against the player's team. Participants included all NYC players who used the CIR during the 2014 season. 2 raters completed video analysis of 131 (of a total of 156 reported) uses of the CIR, describing injury characteristics, situational factors, and concussion signs. The incidence rate was 44.9 (95% CI: 38.5-52.3) uses of the CIR per 1 000 NYC player match hours, or approximately one CIR use every 1.3 games. Apparent loss of consciousness/unresponsiveness was observed in 13% of cases, clutching the head in 65%, unsteadiness of gait in 60%, and a vacant stare in 23%. Most incidences occurred from a hit-up (82%). There appeared to be some instances of video evidence of injury but the athlete was cleared to return to play in the same game. Video review appears to be a useful adjunct for identifying players suffering possible concussion. Further research is required on the usefulness of video review for identifying signs of concussive injury.


Assuntos
Traumatismos em Atletas/diagnóstico , Concussão Encefálica/diagnóstico , Futebol Americano/lesões , Gravação em Vídeo , Humanos , Volta ao Esporte
2.
Rev Med Suisse ; 8(356): 1854-8, 2012 Oct 03.
Artigo em Francês | MEDLINE | ID: mdl-23133886

RESUMO

Severe dysphagia resulting in repeated aspirations and pneumonia are difficult to treat with swallowing therapy and surgical treatment is often required. Our study retrospectively reviews our experience with 19 such cases operated by laryngeal suspension and laryngotracheal separation. Restoration of oral nutrition was possible in 45% of laryngeal suspension cases and in 75% of laryngotracheal separation operations. These surgical techniques prevent severe aspirations while conserving phonation, contrarily to total laryngectomy. Tracheocutaneous fistulas were frequent, especially after radiation, implying that the surgical technique should be modified in the future.


Assuntos
Aspiração Respiratória/cirurgia , Idoso , Transtornos de Deglutição/epidemiologia , Transtornos de Deglutição/reabilitação , Transtornos de Deglutição/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Terapia Nutricional/métodos , Procedimentos Cirúrgicos Otorrinolaringológicos/efeitos adversos , Procedimentos Cirúrgicos Otorrinolaringológicos/métodos , Procedimentos Cirúrgicos Otorrinolaringológicos/reabilitação , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/prevenção & controle , Aspiração Respiratória/epidemiologia , Aspiração Respiratória/reabilitação , Estudos Retrospectivos , Índice de Gravidade de Doença
3.
Eur Radiol ; 20(11): 2628-36, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20862477

RESUMO

OBJECTIVES: The aim of this longitudinal study is to describe the different intralabyrinthine lesions yielding high signal intensity on T1-weighted (T1W) images after intravenous gadolinium and then to analyze the follow-up of these patients. METHODS: Thirty-seven patients were included and followed clinically and radiologically. A precise analysis of MR labyrinthine signals allowed exact depiction of the different lesions. Special interest is focused on the intralabyrinthine fluid signal on 3D high-resolution T2W images. RESULTS: The enhanced T1W labyrinthine hyperintensities correspond to two different categories: intralabyrinthine enhancement (15 intralabyrinthine schwannomas, 13 labyrinthitis, 1 inflammatory granuloma) and spontaneous T1W hyperintensities (8 intralabyrinthine hemorrhages). Hemorrhagic lesions show a substantial decrease of the intralabyrinthine fluid signal on the 3D HRT2 that evolves to ossification. In labyrinthitis, the importance of the initial labyrinthine fluid signal decrease on the 3D HRT2 is well correlated with the hearing prognosis. CONCLUSION: A meticulous analysis of inner ear lesions allows various intralabyrinthine lesions, in particular schwannomas, to be differentiated from labyrinthitis. T1W imaging without gadolinium is essential for the correct diagnosis of rapidly evolving hearing loss. In labyrinthitis and intralabyrinthine hemorrhage, 3D HRT2 brings an interesting prognostic factor for the chance of hearing recovery.


Assuntos
Meios de Contraste , Neoplasias da Orelha/diagnóstico , Gadolínio , Doenças do Labirinto/diagnóstico , Labirintite/diagnóstico , Imageamento por Ressonância Magnética , Neurilemoma/diagnóstico , Adolescente , Adulto , Idoso , Diagnóstico Diferencial , Orelha Interna/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Adulto Jovem
4.
Nature ; 432(7016): 479-82, 2004 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-15565147

RESUMO

Our Solar System was formed from a cloud of gas and dust. Most of the dust mass is contained in amorphous silicates, yet crystalline silicates are abundant throughout the Solar System, reflecting the thermal and chemical alteration of solids during planet formation. (Even primitive bodies such as comets contain crystalline silicates.) Little is known about the evolution of the dust that forms Earth-like planets. Here we report spatially resolved detections and compositional analyses of these building blocks in the innermost two astronomical units of three proto-planetary disks. We find the dust in these regions to be highly crystallized, more so than any other dust observed in young stars until now. In addition, the outer region of one star has equal amounts of pyroxene and olivine, whereas the inner regions are dominated by olivine. The spectral shape of the inner-disk spectra shows surprising similarity with Solar System comets. Radial-mixing models naturally explain this resemblance as well as the gradient in chemical composition. Our observations imply that silicates crystallize before any terrestrial planets are formed, consistent with the composition of meteorites in the Solar System.

5.
Nature ; 429(6987): 47-9, 2004 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-15129274

RESUMO

Active galactic nuclei (AGNs) display many energetic phenomena--broad emission lines, X-rays, relativistic jets, radio lobes--originating from matter falling onto a supermassive black hole. It is widely accepted that orientation effects play a major role in explaining the observational appearance of AGNs. Seen from certain directions, circum-nuclear dust clouds would block our view of the central powerhouse. Indirect evidence suggests that the dust clouds form a parsec-sized torus-shaped distribution. This explanation, however, remains unproved, as even the largest telescopes have not been able to resolve the dust structures. Here we report interferometric mid-infrared observations that spatially resolve these structures in the galaxy NGC 1068. The observations reveal warm (320 K) dust in a structure 2.1 parsec thick and 3.4 parsec in diameter, surrounding a smaller hot structure. As such a configuration of dust clouds would collapse in a time much shorter than the active phase of the AGN, this observation requires a continual input of kinetic energy to the cloud system from a source coexistent with the AGN.

6.
Science ; 153(3740): 1119-20, 1966 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-5331371

RESUMO

Polysomes can be extracted from Escherichia coli by freezing and thawing in the presence of lysozyme, followed by treatment with sodium deoxycholate. The method is simple and convenient; the yields consistently high.


Assuntos
Escherichia coli , Ribossomos , Ácidos e Sais Biliares , Congelamento , Muramidase , Ultracentrifugação
7.
Science ; 276(5321): 2039-42, 1997 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-9197266

RESUMO

Individual plastids of vascular plants have generally been considered to be discrete autonomous entities that do not directly communicate with each other. However, in transgenic plants in which the plastid stroma was labeled with green fluorescent protein (GFP), thin tubular projections emanated from individual plastids and sometimes connected to other plastids. Flow of GFP between interconnected plastids could be observed when a single plastid or an interconnecting plastid tubule was photobleached and the loss of green fluorescence by both plastids was seen. These tubules allow the exchange of molecules within an interplastid communication system, which may facilitate the coordination of plastid activities.


Assuntos
Cloroplastos/metabolismo , Cloroplastos/ultraestrutura , Proteínas Luminescentes/metabolismo , Folhas de Planta/ultraestrutura , Sequência de Aminoácidos , Sequência de Bases , Citoplasma/metabolismo , Proteínas de Fluorescência Verde , Microscopia/métodos , Microscopia de Fluorescência , Dados de Sequência Molecular , Plantas Geneticamente Modificadas , Plantas Tóxicas , Proteínas Recombinantes de Fusão/metabolismo , Nicotiana
8.
J Neuroradiol ; 36(4): 240-3, 2009 Oct.
Artigo em Francês | MEDLINE | ID: mdl-19394696

RESUMO

We report two cases of superior semicircular canal dehiscence related to a dehiscence of the superior petrous sinus that creates a localized notch of the most superior part of the superior semicircular canal. This vascular dehiscence was suspected at CT and was confirmed by MR imaging with identification of the superior petrous sinus in touch with the intralabyrinthine fluid at this level. This not well-known etiology of the superior semicircular canal dehiscence syndrome has to be searched and described by radiologists, allowing an optimal surgical approach.


Assuntos
Cavidades Cranianas/patologia , Osso Petroso/patologia , Canais Semicirculares/patologia , Adulto , Humanos , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Síndrome , Tomografia Computadorizada por Raios X
9.
J Neuroradiol ; 36(2): 74-81, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-18835643

RESUMO

INTRODUCTION: We illustrate here the most common MRI artifacts found on routine 3T clinical neuroradiology that can simulate pathology and interfere with diagnosis. MATERIALS AND METHODS: Our group has worked with a 3-T Magnetom Trio (Siemens, Erlangen, Germany) system for two years, with 50% of our time devoted to clinical work and 50% dedicated to research; 65% of the clinical time is dedicated to neuroradiology (2705 patients) and the remaining time to whole-body MRI. We have detected these artifacts during our case readings and have selected the most representative of each type to illustrate here. RESULTS: We have observed magnetic susceptibility artifacts (29%), pulsation artifacts (57%), homogeneity artifacts (3%), motion artifacts (6%), truncation artifacts (3%) and, finally, artifacts due to poor or inadequate technique in the examined region. CONCLUSION: High-field imaging offers the benefit of a higher signal-to-noise ratio, thus making possible the options of a higher imaging matrix, thinner slices, the use of spectroscopy and diffusion tensor imaging in the routine clinical neuroradiology with a reduction in time spent. It is vital to be able to recognize these artifacts in everyday practice as they can mimic pathological appearances, thus causing diagnostic errors that could lead to unnecessary treatment. Indeed, most of these artifacts could be avoided with an adequate technique.


Assuntos
Artefatos , Encéfalo/patologia , Imageamento por Ressonância Magnética/métodos , Canal Medular/patologia , Medula Espinal/patologia , Humanos , Processamento de Imagem Assistida por Computador
10.
Vet Microbiol ; 132(1-2): 149-57, 2008 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-18514438

RESUMO

To obtain microbiological data from rabbits at slaughter, 500 fecal samples and 500 carcasses samples were examined. All samples tested negative for Listeria and Salmonella. Campylobacter were detected in two fecal samples. Of the 500 fecal samples, 45.8% tested positive for eae (intimin), 1.2% for stx (Shiga toxin), and 1.8% for both eae and stx. By colony hybridization, 56 eae positive Escherichia coli strains were isolated. Among them, 27 strains (48.2%) were of the serotypes O178:H7 and O153:H7, whereas 15 strains (26.8%) belonged to a serogroup that has not yet been described (O(CB10681):H7). All strains possessed intimin beta1 and the translocated intimin receptor (tir) capable of being tyrosine phosphorylated. None of the strains harbored the genes for Shiga toxins, EAST1 (astA), bundlin (bfpA), or the EAF plasmid. Slaughter rabbits therefore constitute a reservoir for certain atypical enteropathogenic Escherichia coli. On rabbit carcasses, average total bacterial counts accounted for 3.3 log CFU cm(-2). Enterobacteriaceae and coagulase positive staphylococci (CPS) were detected on 118 (23.6%) and 153 (30.6%) carcasses, respectively. Enterobacteriaceae and CPS counts of positive samples were mainly <1.5 log CFU cm(-2). Among 153 selected CPS isolates, 98.7% were identified as Staphylococcus aureus. None of the 151 isolated strains harbored the gene for methicillin resistance (mecA). Genes for staphylococcal enterotoxins (SE) were detected in 102 strains. The combinations of seg and sei (53 strains) and sed, seg, sei, and sej (27 strains) dominated.


Assuntos
Bactérias/isolamento & purificação , Microbiologia de Alimentos , Coelhos/microbiologia , Matadouros , Animais , Bactérias/classificação , Fezes/microbiologia
11.
Folia Phoniatr Logop ; 60(3): 151-6, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18340110

RESUMO

OBJECTIVE: It has been the aim of the present study to introduce a novel automatic technique for the objective and quantitative assessment of speech intelligibility to the evaluation of postoperative outcome. PATIENTS AND METHODS: Forty-six patients with oral carcinomas, mean age 59.8 +/- 10.1 years, and an age-matched control group of 40 subjects without oral diseases. Recordings of a standard text read by the patients and the control group were analyzed by an automatic speech recognition system. RESULTS: For the patients, automatic speech recognition yielded word recognition rates between 8 and 82% (mean 49 +/- 19%), for the control group between 60 and 91% (76 +/- 7%). Automatic evaluation closely correlated with the experts' perceptual evaluation of intelligibility (r = -0.93; p < 0.01). The multi-rater kappa of the experts alone (0.55) differed only slightly from the multi-rater kappa of the experts and the speech recognition system (0.58). CONCLUSION: For adults with speech disorders, automatic speech recognition may serve as a valuable tool to assess global speech outcome after treatment of oral squamous cell carcinoma objectively and quantitatively for clinical and research purposes.


Assuntos
Automatismo , Carcinoma de Células Escamosas/complicações , Neoplasias Bucais/complicações , Distúrbios da Fala/etiologia , Inteligibilidade da Fala , Percepção da Fala , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Distúrbios da Fala/diagnóstico , Distúrbios da Fala/epidemiologia
12.
Arch Pediatr ; 15(11): 1717-23, 2008 Nov.
Artigo em Francês | MEDLINE | ID: mdl-18926672

RESUMO

Skiing and snowboarding are leading to a risk of injuries in children. Beginners and experienced have higher risk of injuries, however, the first have less severe injuries than the latest. Risk factors of injury are: ability and experience, binding adjustment, slope characteristics, speed, collisions with objects or jumping and risky behavior of the young skiers and snowboarders. Lower limb injuries are most common in skier, especially knee sprains, conversely snowboarders present more upper limb injuries, especially wrist fractures. The frequency of head injuries does not decrease while helmet use increases but severity decreases. Despite prevention and wearing protections, the frequency of trauma does not decrease significantly, which could be in relation with higher speed and increased risky behavior. Main prevention factors are safety knowledge and safety behavior, correct binding adjustment, and use of protections.


Assuntos
Esqui/lesões , Traumatismos em Atletas/epidemiologia , Traumatismos em Atletas/fisiopatologia , Traumatismos em Atletas/prevenção & controle , Criança , Humanos
13.
Rev Chir Orthop Reparatrice Appar Mot ; 94(3): 217-27, 2008 May.
Artigo em Francês | MEDLINE | ID: mdl-18456056

RESUMO

Congenital hip dislocation has been regularly reviewed, in the wake of important progress made over the last thirty years, and more precisely in the field of clinical and ultrasonographic screening, as well as in early treatment. The search of a consensus on the best screening methods (who? how?) should start from one initial point: a thorough knowledge of anatomical, clinical, pathological and therapeutic definitions and concepts underlying this far-reaching question. This is the purpose of the present review of current ideas (from a historical perspective). The two authors, members of French Society for Paediatric Orthopaedics (SOFOP), have extensively researched this subject and contributed to the implementation of national "good practice".


Assuntos
Luxação Congênita de Quadril/diagnóstico , Luxação Congênita de Quadril/terapia , Humanos , Lactente , Recém-Nascido , Programas de Rastreamento , Terminologia como Assunto
14.
Rev Chir Orthop Reparatrice Appar Mot ; 94(5): 449-55, 2008 Sep.
Artigo em Francês | MEDLINE | ID: mdl-18774019

RESUMO

PURPOSE OF THE STUDY: We present the cases of six adolescents (four high-level gymnastics specialists) with osteochondritis dissecans of the capitulum who were treated with an en bloc osteochondral autograft. There are few series of this rare condition reported in the literature. MATERIAL AND METHODS: All six patients presented pain over the lateral aspect of the elbow and limited extension; pronosupination was unaffected. Physical examination and plain X-rays enabled the diagnosis of osteochondritis dissecans. Postoperative X-rays confirmed good integration of the bone graft. These patients underwent lateral arthrotomy for curettage and avivement followed by an en bloc grafting. The graft was harvested from the homolateral knee via minimal arthrotomy, from a non-weight-bearing zone of the lateral condyle. RESULTS: At three months, complete pain-free range of motion was achieved in four of six patients. Graft integration was confirmed in all six patients on the three months plain X-rays, arthro-CT, or MRI. The four gymnastic specialists resumed their high-level sports activities at one year (at six months for one of them). DISCUSSION: Various surgical methods have been proposed. Series reported in the literature, like ours, have been small, with short follow-up. We have observed good results with an en bloc graft, encouraging us to continue with this surgical strategy.


Assuntos
Transplante Ósseo , Cartilagem Articular/transplante , Articulação do Cotovelo , Úmero , Osteocondrite Dissecante/cirurgia , Adolescente , Articulação do Cotovelo/fisiologia , Feminino , Seguimentos , Ginástica , Humanos , Úmero/cirurgia , Masculino , Osteocondrite Dissecante/diagnóstico por imagem , Osteocondrite Dissecante/reabilitação , Exame Físico , Radiografia , Amplitude de Movimento Articular , Fatores de Tempo , Transplante Autólogo , Resultado do Tratamento
15.
Rev Chir Orthop Reparatrice Appar Mot ; 94(5): 510-4, 2008 Sep.
Artigo em Francês | MEDLINE | ID: mdl-18774027

RESUMO

Several methods are available for progressive limb lengthening, including centromedullary nailing, external fixation, or a combination. Each technique has its own advantages and drawbacks. In trauma victims, use of centromedullary nailing is associated with potentially fatal fat embolism. This fatal outcome might also occur during limb lengthening, particularly in bilateral procedures. To our knowledge, fat embolism has not been reported with the use of centromedullary nail for limb lengthening. This was a multicentric study of three cases of fat embolism, including one fatal outcome. In all, 36 centromedullary lengthening nails were inserted in the three centers before these acute episodes. The first two cases occurred during single-phase bilateral procedures, the third during unilateral lengthening. Fat embolism could result from several factors, as reported in the literature. While the bilateral nature of the procedure has been incriminated, the observation of an embolism during a unilateral procedure suggests other factors may be involved. Considerable increase in endomedullary pressure during reaming and insertion of the nail has been demonstrated. At the same time, there is the question as to whether the reduction of the diminution of medullary pressure by corticotomy would be an efficient way of reducing the risk of fat embolism. Based on the analysis of our three cases, we suggest that the best way to avoid fat embolism might be to drill several holes within the area of the osteotomy before reaming, in order to reduce endomedullary pressure. This can be achieved via a short skin incision, sparing the periosteum before low energy osteotomy. Since applying this protocol, the three centers have implanted 17 lengthening nails, without a single case of fat embolism.


Assuntos
Alongamento Ósseo/efeitos adversos , Alongamento Ósseo/métodos , Pinos Ortopédicos , Embolia Gordurosa/etiologia , Fêmur/cirurgia , Desigualdade de Membros Inferiores/cirurgia , Adolescente , Pinos Ortopédicos/efeitos adversos , Protocolos Clínicos , Embolia Gordurosa/mortalidade , Feminino , Humanos , Masculino , Osteotomia , Edema Pulmonar/diagnóstico por imagem , Edema Pulmonar/etiologia , Radiografia Torácica , Tomografia Computadorizada por Raios X , Adulto Jovem
16.
Rev Chir Orthop Reparatrice Appar Mot ; 93(7): 674-81, 2007 Nov.
Artigo em Francês | MEDLINE | ID: mdl-18065878

RESUMO

PURPOSE OF THE STUDY: Spasticity can be the cause of pain in cerebral palsy (CP) children who may suffer increased postoperative pain after orthopedic surgery. Moreover, symptoms can be worsened by abnormal movements, cast immobilization or anxiety. Spasticity must therefore be treated after surgery in CP children. A randomized study has demonstrated that when these children undergo surgical tenotomy, preoperative injections of botulinum toxin have a beneficial effect in terms of pain relief. The aim of this study was to assess the benefit regarding pain and comfort provided by preoperative use of botulinum toxin in total-body CP children undergoing bone surgery. MATERIAL AND METHODS: Two successive groups of nine total-body CP children were compared in a retrospective study. All patients underwent an orthopedic surgery involving a bone or a multilevel procedure. The second group was treated before surgery with multisite injections of botulinum toxin. The main outcome criteria studied were: efficiency and adverse effects of botulinum toxin, duration of hospital stay and pain, length of level III analgesic treatment (morphine), sleep quality, and skin lesions under cast immobilization. The two groups were similar for mean age (8.7+/-2.04 versus 10.9+/-4.37 years) and mean body weight (20+/-5.6 versus 26+/-7.7 kg). Mean botulinum toxin (Botox/kg) in the second group was 11.6 U (range 9.7-14.8). Average time from preoperative botulinum toxin injections to surgery was 27 days (range 23-31). RESULTS: There was no significant difference between the two groups, except for the botulinum toxin treatment. The Aschworth scale confirmed the clinical efficiency of the preoperative injections, with no adverse effects. After the surgical procedure, all patients but two had cast immobilization (orthopedic traction, in botulinum group). The mean duration was six weeks in both groups. There was no significant difference in duration of the hospital stay: 7.33+/-1.5 versus 7.88+/-1.7 days and duration of level III analgesic treatment (4.33+/-1.9 versus 4.16+/-2.5 days). The duration of pain symptoms decreased significantly from 6.87+/-2.9 to 2.22+/-1.7 days and sleep quality improved from 7/9 to 1/9 patients with disturbed sleep. Four under-cast skin lesions were noted in the first group but none in the bolulinum group. DISCUSSION: We cannot confirm that botulinum toxin before bone surgery induces lesser consumption of analgesic drugs. Our results do however support the hypothesis that treatment of spasticity using preoperative injections of botulinum toxin decreases the duration of postoperative pain and improves the children's comfort. Moreover, postoperative under-cast skin lesions can be prevented. This work suggests that improved patient comfort and pain relief could be achieved by using multisite botulinum toxin injections before orthopedic surgery in spastic total-body CP children.


Assuntos
Toxinas Botulínicas Tipo A/uso terapêutico , Paralisia Cerebral/cirurgia , Fêmur/cirurgia , Fármacos Neuromusculares/uso terapêutico , Procedimentos Ortopédicos , Dor Pós-Operatória/prevenção & controle , Pré-Medicação , Adolescente , Toxinas Botulínicas Tipo A/administração & dosagem , Moldes Cirúrgicos , Criança , Feminino , Humanos , Tempo de Internação , Masculino , Morfina/uso terapêutico , Espasticidade Muscular/prevenção & controle , Entorpecentes/uso terapêutico , Fármacos Neuromusculares/efeitos adversos , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Retrospectivos , Dermatopatias/etiologia , Sono/efeitos dos fármacos , Fatores de Tempo , Tração , Resultado do Tratamento
17.
Rev Chir Orthop Reparatrice Appar Mot ; 93(7): 690-700, 2007 Nov.
Artigo em Francês | MEDLINE | ID: mdl-18065880

RESUMO

PURPOSE OF THE STUDY: Appropriate treatment of patellar dislocation in children and adolescents remains a subject of debate. Ligamentous transfer or "soft rod" is a technique for realigning the extensor mechanism that can be adapted to children. We analyzed results obtained in our patients. MATERIAL AND METHODS: Between 1979 and 2000, 35 children (50 knees) underwent realignment which was combined in all cases with lateral retinacular release and medial reefing using the Insall procedure. Complementary procedures were needed in certain cases (quadriceps lengthening, femoral sulcus plasty, quadriceps release). Mean age at surgery was 11 years, range 5-15 years. All patients were reviewed at skeletal maturity with a mean follow-up of 7.5 years. The last review included a functional assessment using the IKDC form and standard x-rays (anteroposterior and lateral standing view and tangential view at 30 degrees flexion). A computed tomography scan and/or magnetic resonance imaging series were done preoperatively and at last follow-up. DISCUSSION: We distinguished two groups of patients, those with major (permanent or habitual) dislocation of the patella and those with recurrent dislocation. Functional outcome was good in 76% and 86% of knees respectively. There were eight cases of recurrent dislocation: five knees underwent revision surgery with good outcome. The femoral sulcus angle was improved in both groups, but especially in the congenital dislocation group. There was on case of reversed tibial slope (-2 degrees) ant to slopes at 0 degrees. Functional outcome was equivalent to results from earlier series (Grammont, Bensahel, Langeskiold), but comparison was hampered due to the heterogeneous nature of the different series. Femoral sulcus remodeling can enable good patellar stability if the surgery is performed early enough (before age 10 years). In teenagers with major instability, femoral sulcus plasty must be associated with the realignment procedure. We noted a small amplitude reduction of the tibial slope in eleven knees. The procedure appears to have an "epiphysiodesis effect" but with no functional consequence. CONCLUSION: Ligamentous transfer combined with different procedures is a method of choice for stabilizing the extensor system, enabling a normal femoral sulcus angle if the child is operated early. Remodeling of the tibial tuberosity could be related to a transient vascular disorder.


Assuntos
Luxação Patelar/cirurgia , Ligamento Patelar/cirurgia , Adolescente , Criança , Pré-Escolar , Feminino , Fêmur/cirurgia , Seguimentos , Humanos , Imageamento por Ressonância Magnética , Masculino , Luxação Patelar/congênito , Periósteo/cirurgia , Músculo Quadríceps/cirurgia , Amplitude de Movimento Articular/fisiologia , Recidiva , Reoperação , Estudos Retrospectivos , Rotação , Tomografia Computadorizada por Raios X , Resultado do Tratamento
18.
Science ; 356(6334): 194-197, 2017 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-28408604

RESUMO

DNA transcription is functionally coupled to messenger RNA (mRNA) translation in bacteria, but how this is achieved remains unclear. Here we show that RNA polymerase (RNAP) and the ribosome of Escherichia coli can form a defined transcribing and translating "expressome" complex. The cryo-electron microscopic structure of the expressome reveals continuous protection of ~30 nucleotides of mRNA extending from the RNAP active center to the ribosome decoding center. The RNAP-ribosome interface includes the RNAP subunit α carboxyl-terminal domain, which is required for RNAP-ribosome interaction in vitro and for pronounced cell growth defects upon translation inhibition in vivo, consistent with its function in transcription-translation coupling. The expressome structure can only form during transcription elongation and explains how translation can prevent transcriptional pausing, backtracking, and termination.


Assuntos
RNA Polimerases Dirigidas por DNA/química , Escherichia coli/genética , Biossíntese de Proteínas , RNA Mensageiro/química , Ribossomos/química , Transcrição Gênica , Microscopia Crioeletrônica , Domínios Proteicos , RNA Bacteriano/química
19.
Acta Physiol (Oxf) ; 219(1): 176-187, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27497091

RESUMO

It has been suggested that the transient receptor potential cation (TRP) channel subfamily V (vanilloid) type 4 (TRPV4) and intermediate conductance calcium-activated potassium (KCa3.1) channels contribute to endothelium-dependent vasodilation. Here, we summarize very recent evidence for a synergistic interplay of TRPV4 and KCa3.1 channels in lung disease. Among the endothelial Ca2+ -permeable TRPs, TRPV4 is best characterized and produces arterial dilation by stimulating Ca2+ -dependent nitric oxide synthesis and endothelium-dependent hyperpolarization. Besides these roles, some TRP channels control endothelial/epithelial barrier functions and vascular integrity, while KCa3.1 channels provide the driving force required for Cl- and water transport in some cells and most secretory epithelia. The three conditions, increased pulmonary venous pressure caused by left heart disease, high inflation pressure and chemically induced lung injury, may lead to activation of TRPV4 channels followed by Ca2+ influx leading to activation of KCa3.1 channels in endothelial cells ultimately leading to acute lung injury. We find that a deficiency in KCa3.1 channels protects against TRPV4-induced pulmonary arterial relaxation, fluid extravasation, haemorrhage, pulmonary circulatory collapse and cardiac arrest in vivo. These data identify KCa3.1 channels as crucial molecular components in downstream TRPV4 signal transduction and as a potential target for the prevention of undesired fluid extravasation, vasodilatation and pulmonary circulatory collapse.


Assuntos
Pulmão/metabolismo , Canais de Potássio Cálcio-Ativados/metabolismo , Circulação Pulmonar/fisiologia , Edema Pulmonar/metabolismo , Canais de Potencial de Receptor Transitório/metabolismo , Animais , Cálcio/metabolismo , Endotélio Vascular/metabolismo , Humanos
20.
Circ Res ; 87(6): 496-503, 2000 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-10988242

RESUMO

Ca(2+)-activated K(+) (K(Ca)) channels have been suggested to play a role in the control of endothelial functions such as regulation of vascular tone and cell proliferation. We established a method for single-cell reverse transcriptase-polymerase chain reaction analysis in combination with the patch-clamp technique to characterize K(Ca) channel expression and function in single endothelial cells (ECs) within the endothelial monolayer of intact human mesenteric arteries (MAs) and in disease states. We tested whether endothelial K(Ca) channel expression and function are altered in MAs obtained from patients with colonic adenocarcinoma (CA) compared with those in MAs from non-cancer patients with inactive diverticulitis. Expression of the intermediate-conductance K(Ca) channel (hIK1) was detected in non-cancer and CA patients. In whole-cell patch-clamp measurements, only ECs expressing hIK1 exhibited corresponding K(Ca) currents, whereas respective K(Ca) currents were missing in hIK1-negative ECs. This heterogeneity of hIK1 expression patterns is indicative of a specialized subset of ECs within the endothelial monolayer. In CA patients, compared with non-cancer patients, a 2.5-fold increase in hIK1-expressing ECs per MA was observed (P:<0.05). However, K(Ca) current densities in hIK1-expressing ECs of both groups were similar. In addition to hIK1, expression of the large-conductance K(Ca) channel (hSlo) was detected in single ECs from CA patients. The increased K(Ca) channel expression in CA patients resulted in a 2. 7-fold increase of bradykinin-induced endothelial hyperpolarization compared with controls (P:<0.05). This increased expression and function of K(Ca) channels might indicate an altered functional state of the endothelium in cancer patients and could play a role in tumor angiogenesis.


Assuntos
Cálcio/fisiologia , Endotélio Vascular/metabolismo , Artérias Mesentéricas/metabolismo , Canais de Potássio Cálcio-Ativados , Canais de Potássio/metabolismo , Adenocarcinoma/irrigação sanguínea , Neoplasias do Colo/irrigação sanguínea , Endotélio Vascular/patologia , Humanos , Técnicas In Vitro , Canais de Potássio Ativados por Cálcio de Condutância Alta , Artérias Mesentéricas/patologia , Técnicas de Patch-Clamp , Canais de Potássio/fisiologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa
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