RESUMO
Twenty-one patients with an average age of 65 years had displaced femoral neck fractures treated by a sliding compression screw and two Knowles pins. All patients had either Garden III or Garden IV fractures. One patient healed with a malunion and five developed symptomatic avascular necrosis; all of these patients required reconstructive surgery. There were no nonunions. The sliding compression screw with two Knowles pins gave a 100% rate of union, which was superior to most fixation methods. The incidence of avascular necrosis was 24%, the expected range for displaced femoral neck fractures.
Assuntos
Pinos Ortopédicos , Parafusos Ósseos , Fraturas do Colo Femoral/cirurgia , Idoso , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Osteonecrose/etiologia , Complicações Pós-OperatóriasRESUMO
The trabecular bone mineral content (BMC) of the spine was measured by computed tomography in 185 women aged 47-84 years with vertebral fracture (n = 74), hip fracture (n = 83), and both vertebral and hip fracture (n = 28). Eighty-seven percent of vertebral-fracture patients, 38% of hip-fracture patients, and 82% of vertebral- and hip-fracture patients had spinal BMC values below the fifth percentile for healthy premenopausal women and values 64%, 9%, and 68% below the fifth percentile for age-matched control subjects. No significant loss of spinal trabecular bone was seen in patients with hip fracture. If it is assumed that the rate of trabecular bone loss is the same in the spine and femoral neck, then hip fracture (unlike osteoporotic vertebral fracture) is not associated with disproportionate loss of trabecular bone. Hip fracture occurs secondary to weakening of bone and increased incidence of falls. Bone weakening may be due to disproportionate loss of trabecular or cortical bone, proportionate loss of both, or other as yet undetermined qualitative changes in bone.
Assuntos
Fraturas do Quadril/metabolismo , Minerais/análise , Coluna Vertebral/análise , Tomografia Computadorizada por Raios X , Absorciometria de Fóton , Idoso , Feminino , Fraturas Ósseas/metabolismo , Fraturas do Quadril/complicações , Fraturas do Quadril/diagnóstico por imagem , Humanos , Vértebras Lombares/lesões , Pessoa de Meia-Idade , Osteoporose/complicações , Osteoporose/metabolismo , Estudos Prospectivos , Coluna Vertebral/diagnóstico por imagem , Vértebras Torácicas/lesões , Tomografia Computadorizada por Raios X/métodosRESUMO
Denaturation of Bacillus thuringiensis CryIIIA delta-endotoxin--an insecticidal protein, active against Coleoptera larvae--in concentrated guanidine hydrochloride solutions was pursued by fluorescence and circular dichroism spectroscopy and limited proteolysis. It was found that the protein consists of two fragments that differ by their stability to denaturation by guanidine hydrochloride at pH 3. The less stable fragment corresponds to the N-terminal alpha-helical domain limited by Leu-279; the more stable one starts with Ile-280, contains about 330 amino acid residues, and corresponds to the molecule C-terminal moiety that consist of its two beta-structural domains forming a superdomain.