False aneurysm of the superior lateral geniculate artery following Total Knee Replacement.

Arterial complications following Total Knee Replacement are uncommon. We present a case of false aneurysm of the superior lateral geniculate artery presenting in the immediate postoperative period with continued bleeding from the surgical wound. This is the first case of false aneurysm of this vessel described following Total Knee Replacement.

Solution structure of the calponin CH domain and fitting to the 3D-helical reconstruction of F-actin:calponin.

Calponin is involved in the regulation of contractility and organization of the actin cytoskeleton in smooth muscle cells. It is the archetypal member of the calponin homology (CH) domain family of actin binding proteins that includes cytoskeletal linkers such as alpha-actinin, spectrin, and dystrophin, and regulatory proteins including VAV, IQGAP, and calponin. We have determined the first structure of a CH domain from a single CH domain-containing protein, that of calponin, and have fitted the NMR-derived coordinates to the 3D-helical reconstruction of the F-actin:calponin complex using cryo-electron microscopy.

Cardiac and skeletal myopathies: can genotype explain phenotype?

The inherited muscle diseases, skeletal muscle nemaline myopathy and cardiac muscle hypertrophic myopathy (HCM) have been recognised for decades. Recently it has become apparent that mutations in almost any protein component of the sarcomere could cause myopathy. Thus changes in many sarcomeric protein genes can produce a common phenotype.

Evaluation of the specificity of five oligoprobes for identification of cyathostomin species from horses.

Here, we report evaluation of five oligoprobes designed from intergenic spacer (IGS) region sequences for identification of cyathostomin species. Oligoprobes were designed for identification of Cylicocyclus ashworthi, Cylicocyclus nassatus, Cylicostephanus longibursatus, Cylicostephanus goldi and a fifth probe designed to identify all members of this tribe. PCR amplification of IGS DNA from 16 cyathostomin species allowed sequence comparison and identification of four putative species-specific probes.

Two-stage revision with pseudocapsular resection for recurrent dislocation of total hip prostheses.

Recurrent dislocation of the prosthesis is a problem with total hip arthroplasty. In the rare cases in which no identifiable cause can be found for the recurrent dislocation, we believe that the answer lies in addressing the large, sterile, fluid-filled cavity bounded by pseudocapsule, which we have noticed to form around the neck of the femoral implant in these cases. We report a 2-stage surgical technique that we have used successfully in 3 cases of recurrent dislocation without an identifiable cause, with an average follow-up of 3 years.

Actin and the smooth muscle regulatory proteins: a structural perspective.

The structural details of the smooth muscle acto-myosin interaction and its functional implications have been much discussed in recent years, however other, smooth muscle specific, actin-binding proteins have received much less attention. With increasing technical advances in structural biology a great deal of structural information is now coming to light, information that can provide useful insight into the mechanism of action for many important nonmotor actin-binding proteins. The purpose of the review is to instill the current knowledge on the structure, and interaction sites on F-actin, of the major, non-motor actin-binding proteins from smooth muscle, proposed to have a role in regulation.

Continuous neonatal blood gas monitoring using a multiparameter intra-arterial sensor.

Aims: To compare arterial blood gas (ABG) readings obtained with a multiparameter intra-arterial sensor with those from an ABG analyser.

Methods: An MPIAS with the ability to measure continuously pH, PaCO2, and PaO2 was introduced via an umbilical arterial catheter in 27 neonates requiring intensive care. They underwent 3260 hours of MPIAS monitoring, during which 753 ABG readings were performed.

Structural interactions between actin, tropomyosin, caldesmon and calcium binding protein and the regulation of smooth muscle thin filaments.

The basic structure and functional properties of smooth muscle thin filaments were established about 10 years ago. Since then we and others have been working on the details of how tropomyosin, caldesmon and the Ca(2+)-binding protein regulate actin interaction with myosin. Our work has tended to emphasize the similarities between caldesmon and troponin function whilst others have been more concerned with the differences.

The effect of sodium tetradecyl sulfate on mobility and antigen detectability of microtubule proteins in sodium dodecyl sulfate-polyacrylamide gel electrophoresis.

Several factors been reported to influence the mobility of polypeptide in sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) including the brand of SDS. Using microtubule proteins from axonemes of Lytechinus pictus and Spisula solidissima sperm and meiotic spindles of Spisula solidissima we demonstrate that the change in mobility was caused by sodium tetradecyl sulfate (STS), a major contaminant of many commercial SDS brands. We also examined the use of sodium tetradecyl sulfate and different SDS brands as a tool in extracting more information from immunoblot studies.

3-D image reconstruction of reconstituted smooth muscle thin filaments containing calponin: visualization of interactions between F-actin and calponin.

Calponin is a putative thin filament regulatory protein of smooth muscle that inhibits actomyosin ATPase in vitro. We have used electron microscopy and three-dimensional reconstruction to elucidate the structural organization of calponin on actin and actin-tropomyosin filaments. Calponin density was clearly delineated in the reconstructions and found to occur peripherally along the long-pitch actin-helix.

Three-dimensional image reconstruction of reconstituted smooth muscle thin filaments: effects of caldesmon.

Caldesmon inhibits actomyosin ATPase and filament sliding in vitro, and therefore may play a role in modulating smooth and non-muscle motile activities. A bacterially expressed caldesmon fragment, 606C, which consists of the C-terminal 150 amino acids of the intact molecule, possesses the same inhibitory properties as full-length caldesmon and was used in our structural studies to examine caldesmon function. Three-dimensional image reconstruction was carried out from electron micrographs of negatively stained, reconstituted thin filaments consisting of actin and smooth muscle tropomyosin both with and without added 606C.

Immunogold localisation of the intermediate chain within the protein complex of cytoplasmic dynein.

It was our goal to determine the location of the intermediate chain within the complex of cytoplasmic dynein by immunoelectron microscopy. To do so we generated two monoclonal antibodies (m74-1 and m74-2) specific for the intermediate chain. Both antibodies recognised the intermediate chain by sodium dodecyl sulphate-polyacrylamide gel electrophoresis immunoblot and ELISA assays of native and denatured proteins.

Acrylic bone-cement. Influence of mixer design and unmixed powder.

The effects of hand mixing with two different mechanical mixing systems (fixed versus rotating central axis) on unmixed powder content, macroporosity, density, and bending strength of acrylic bone-cement are compared. The effects of voids and unmixed powder on cement bending strength are also evaluated. In acrylic cement, both unmixed powder monomer and voids 1 mm and larger can be easily visualized and analyzed on radiographs of 3-mm-thick samples.

The perceived relationship between back symptoms and preceding injury.

A questionnaire was used to gather information regarding the prevalence of minor back symptoms related to performing everyday tasks, including sitting, lifting, etc. in a population of hospital employees. We studied 175 subjects, of whom 111 had not suffered a back injury.

The structure of the contractile apparatus in ultrarapidly frozen smooth muscle: freeze-fracture, deep-etch, and freeze-substitution studies.

The structure of the smooth muscle contractile apparatus was studied using ultrarapid freezing followed by freeze substitution or by longitudinal freeze-fracture, deep-etch, and platinum-carbon replication. Freeze substitution minimises the detrimental effects of chemical fixation and freeze fracture eliminates them entirely whilst revealing the ultrastructure in three dimensions. Unidirectionally shadowed freeze-fracture replicas of ultrarapidly frozen, relaxed, intact smooth muscle showed a well-preserved actin filament structure the 5.

The perceived relationship between neck symptoms and precedent injury.

A questionnaire survey of 328 hospital employees was used to establish the general prevalence of neck symptoms related to everyday activities in a representative population of working society. The response rate was 92 per cent. Of the study population of 302, 54 had suffered neck injury, and of this group, 43 (80 per cent) had some neck discomfort during or after performing normal everyday tasks.

Filamin and gelsolin influence Ca(2+)-sensitivity of smooth muscle thin filaments.

Sheep aorta thin filaments were prepared by ultracentrifugation of an ATP-containing extract in the presence of different concentrations of ethanediol. Thin filaments prepared without ethanediol contained small quantities of tropomyosin (0.027 Tm:actin) and caldesmon (0.

Activity and socket wear in the Charnley low-friction arthroplasty.

A clinical study was undertaken to assess the influence of patient-related factors on wear of the socket in Charnley low-friction arthroplasty. One hundred nine arthroplasties in 79 patients were reviewed at an average of 10.3 years.

Expression of a human homeobox-containing gene is regulated by 1,25(OH)2D3 in bone cells.

The murine msh-like homeobox-containing gene Msx-2 (Hox-8) has a multiphasic pattern of embryonic expression which includes the developing skull bones and teeth. In order to determine whether this gene might be expressed in adult mineralizing tissues, an adult human bone cell (osteoblastic) cDNA library was screened with a murine Msx-2 probe. One of the positive clones obtained was sequenced in full and shown to be highly homologous to the murine Msx-2 gene.

Flanged acetabular components in cemented Charnley hip arthroplasty. Ten-year follow-up of 350 patients.

A flanged socket was introduced by Sir John Charnley for use in his low-friction hip arthroplasty in 1976. Experimental evidence has suggested that the flange offers an advantage in terms of cement pressurisation at the time of implantation. We have reviewed 302 primary Charnley arthroplasties followed for 9 to 11 years to determine the effect of the flanged socket on the radiological appearance.

How common are polycystic ovaries in normal women and what is their significance for the fertility of the population?

Objective: We wished to determine the prevalence of polycystic ovaries (PCO) and relate morphological appearance to fertility.

Design: We sent postal invitations to a random sample of women born in the years 1952-1969 from a list of a single Group Practice to attend for reproductive history questionnaire, examination, ultrasound scan of the ovaries and hormone measurements within 5 days of the onset of menstruation.

Subjects: Of 1065 women potentially available for study, 571 (54%) replied of whom 353 (62%) agreed to participate.

X-ray solution scattering studies on vinblastine-induced polymers of microtubule protein: structural characterisation and effects of temperature.

We report here on X-ray solution scattering and electron microscopy studies of microtubule protein in the presence of the antimitotic drug, vinblastine. In buffer conditions used for microtubule assembly, vinblastine caused the formation of coil-like structures. The coils appeared to be made up of two protofilaments.

Treatment of fracture of the shaft of the femur in total hip arthroplasty by a combination of a Küntscher nail and a modified cemented Charnley stem.

Eight cases of fracture of the femoral shaft in total hip arthroplasty were treated by a combination of a Küntscher nail and a modified Charnley stem with cement. Radiological union was achieved in all patients at an average of 8 months.