Changes in muscle blood flow distribution during hyperthermia

Blood flow is a critical parameter for obtaining satisfactory temperature distributions during clinical hyperthermia. This study examines the changes in blood flow distribution in normal porcine skeletal muscle before, during and after a period of regional microwave hyperthermia. The baseline blood flow distribution during general anaesthesia and after the insertion of the thermal probes was established independently in order to isolate the changes due to hyperthermia. General anaesthesia alone and thermocouple insertion during anesthesia had no significant effect on the muscle blood flow distribution. Regional microwave heating generated a non-uniform blood flow distribution which was a function of the tissue temperature distribution. Blood flow was greater in those tissues samples in which higher temperatures were recorded and less in those sampled further from the applicators peak SAR (Specific Absorption Rate). The increase in blood flow appears to be primarily a local phenomenon. Although muscle blood flow may be considered to be uniform prior to heating, this does not hold during hyperthermia treatment. Therefore, the non-uniform nature of the blood distribution during heating should be incorporated into any practical bioheat transfer model.     

Late onset peripheral seronegative spondyloarthropathy: report of two additional cases

Two more cases of late onset peripheral seronegative spondyloarthropathy (SpA) are reported. Like the patients reported by Dubost and Sauvezie, they had extensive pitting edema of the lower limbs, constitutional symptoms, elevated erythrocyte sedimentation rate and minimal involvement of the axial skeleton with marked signs of diffuse idiopathic skeletal hyperstosis.     

Evolution of peptides that modulate the spectral qualities of bound, small-molecule fluorophores

BACKGROUND: Fluorophore dyes are used extensively in biomedical research to sensitively assay cellular constituents and physiology. We have created, as proof of principle, fluorophore dye binding peptides that could have applications in fluorescent dye-based approaches in vitro and in vivo. RESULTS: A panel of Texas red, Rhodamine red, Oregon green 514 and fluorescein binding peptides, termed here 'fluorettes', was selected via biopanning of a combinatorial library of 12-mer peptides fused to a minor coat pIII protein of the filamentous bacteriophage M13. The 'best' fluorette sequences from each of the groups were subjected to further mutagenesis, followed by a second biopanning to select a new generation of improved fluorettes. Phage were selected that had higher avidity for each fluorophore except Rhodamine red. Of these, peptides were characterized that could specifically and with high affinity bind at least one dye, Texas red, in solution. In addition, the binding of certain peptides to Texas red shifted the peak excitation and/or the emission spectra of the bound dye. CONCLUSIONS: Peptides in the context of phage display could readily be selected that could bind to small-molecule fluorophores. The affinities of selected mutant fluorettes could be increased by mutation and further selection. Only a subset of the free peptides could bind free dyes in solution, suggesting that phage context contributed to the selection and ability of certain peptidic regions to independently bind the dyes. Future screens might lead to the creation of other dye-binding peptides with novel characteristics or Texas red derivatives with cross-linking substituents might be designed to increase the utility of the system.     

Aortic corset syndrome

The majority of proximal anastomotic complications of aortofemoral bypass grafts are related to the formation of pseudoaneurysms or true proximal aneurysmal dilation of the residual infrarenal aorta. The late development of occlusive disease at the proximal anastomosis is an extremely rare event. We report two patients in whom symptomatic stenoses developed involving the proximal anastomoses of aortofemoral bypass grafts originally placed for aortoiliac occlusive disease. Surgical exploration demonstrated the presence of a constricting prosthetic corset wrapped around the proximal suture line of each graft. Exuberant neointimal hyperplasia was responsible for both stenoses.     

Challenges in the human genome project

The purpose and scope of the human genome project are discussed. Basic biological concepts underlying the project are reviewed. The two processes-logic and experimentation-used to understand DNA sequences are compared, and the process of obtaining the sequence is described. Two problem areas in this collaboration between biologists and computer scientists are examined. They arise from differences in training that can make communication difficult, and nomenclature problems     

The "pedrada" ("coup-de-fouet") syndrome. A possibility to be considered in acute leg pain

The authors report the case of a woman admitted to hospital for minor trauma of the left hip and who presented major ST segment elevation on the second day suggesting an acute anterior wall myocardial infarction at the same time as a cerebrovascular accident. Complementary investigations and follow-up excluded the diagnosis of myocardial infarction with normalisation of the ECG on the 5th day. ECG changes during cerebrovascular accidents may be very variable ranging from extrasystoles to ST elevation mimicking myocardial infarction. They carry a poor prognosis with an increased risk of sudden death necessitating continuous ECG monitoring until the ECG reverts to normal. The cardiac involvement is not ischaemic but due to disease of the insular cortex of the brain which induces myocytolysis (centered around the intra-cardiac nerve endings) due to the sudden liberation of catecholamines. These lesions may be treated by propranolol or phentolamine.     

Cement versus cementless fixation in total knee arthroplasty

A prospectively studied group of 55 uncemented Press Fit Condylar total knee arthroplasties was compared retrospectively with a matched group of 51 cemented Press Fit Condylar total knee arthroplasties at a mean of 10 years after operation. For the cemented group, the pain and function scores improved from 32 and 45 preoperatively to 95 and 77, respectively. For the uncemented group the scores improved from 33 and 50 preoperatively to 93 and 60, respectively. There were 10 revisions in the uncemented group for femoral or tibial aseptic loosening or osteolysis compared with two revisions in the cemented group. Exclusive of problems related to patellar metal backing, survival to revision for aseptic failure or radiographic loosening was 72% in the uncemented group and 94% in the cemented group at 10 years. A significantly higher revision rate was found in the uncemented compared with cemented total knee arthroplasty of the Press Fit Condylar design.