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J Melhuish

Publications and source records attributed to J Melhuish.

9 recordsLinked to original sources

Measurement of forces associated with compression therapy.

Compression therapy is the principal treatment for leg ulcers associated with venous disease. The efficacy of compression therapy can be variable, which may in part be owing to the degree of compression applied. However, if the mechanism of action of this treatment could be better understood, it might be possible to improve its efficacy. It is not clear whether assessment of the degree of compression should be made under static or dynamic conditions, or both. A review of methods used previously suggests the need for a new method of assessment allowing continuous monitoring, even during movement. A system for continuous static and dynamic measurements of compression is described. Using an air chamber and manometer to test the system, agreement within +/- 3 mmHg is observed. The system is applied to investigate changes in forces, expressed as pressure, under bandages and compression stockings. Application of five bandage systems by experienced nurses to a volunteer shows a marked variation in applied pressure. During short periods of walking, rapid changes in pressure under compression stockings are observed, including some transients of less than 0.25 s. The method is simple to apply and may help to understand further the mechanism of action of compression therapy.

Bandages↗

Movement-related variation in forces under compression stockings.

OBJECTIVES: Compression therapy is widely used in the treatment of venous leg ulcers, but the efficacy of this treatment is variable. Assessment of variation in compression forces associated with movement may help to elucidate the mechanism of action of compression therapy. The aim of this study was to develop and apply a system to investigate forces under compression stockings during movement. METHOD: Three sensors were placed on the medial aspect of the left leg on six healthy volunteers to monitor forces under class 2 (Continental European classification) compression stockings. Data were recorded during dorsiflexion and plantar flexion of the left foot and also during short periods of walking. RESULTS: Changes in pressure were observed, associated with dorsiflexion and plantar flexion of the foot. These changes were dependent on sensor position. Changes in pressure during walking were also position-dependent and of variable duration. CONCLUSIONS: The system enables forces associated with compression therapy to be examined during movement and may thus be of value in further understanding its mechanism of action. Foot movement can be associated with clear changes in pressure under compression stockings and rapid changes in pressure may occur during walking.

Adult↗

Suppression of phase separation in solutions of bovine gamma IV-crystallin by polar modification of the sulfur-containing amino acids.

The calf lens protein gamma IV-crystallin, a strong determinant of the net phase-separation temperature of the lens, was chemically modified with N-bromoacetylethanolamine phosphate. The phase-separation temperatures of solutions of the modified protein were measured and found to be dramatically reduced with respect to those of the native protein. At neutral pH the reagent alkylates only the cysteine and methionine residues and introduces a doubly charged phosphate anion at a maximum distance of 10-12 A from the sulfur atoms. At a protein concentration of 38 g/liter, and with 30% of the cysteines and 40% of the methionines alkylated, the phase-separation temperature is lowered from approximately 25 +/- 2 degrees C to approximately 12 +/- 2 degrees C. The ascending limbs of the coexistence curves for the native and modified proteins were determined at two different degrees of modification. The coexistence curve of the protein with 35% of the cysteines and 40% of the methionines modified shows that as protein concentration approaches the critical concentration of 289 g/liter, there is a much larger suppression of the critical temperature, from approximately 38 +/- 2 degrees C in the native protein to approximately 16 +/- 2 degrees C. Incubation of intact calf lenses in vitro with the reagent results in the suppression of the phase-separation temperature by 3-9 degrees C. These results are consistent with the view that the observed suppression in the critical temperature is due to an increase in the hydrophilicity of the protein in the vicinity of the sulfur-containing residues.

Animals↗

A randomized trial of dietary intervention with essential fatty acids in patients with categorized cysts.

Two hundred women with breast cysts proven by aspiration were entered into a randomized double-blind trial of Efamol (evening primrose oil) at a dose of 6 capsules daily or equivalent placebo dose for a year. Cysts were categorized by initial electrolyte composition, and follow-up continued for 1 year posttherapy. Recurrent cyst formation in the first year was slightly (but not significantly) lower in the Efamol group compared with the placebo-treated group. The Efamol treatment was well tolerated as the dropout rate was only 7% and equal in both the active and placebo groups. The initial electrolyte composition did not predict for cyst recurrence.

Adult↗

Viscoelastic properties and collagen content of the long saphenous vein in normal and varicose veins.

Veins taken from patients undergoing surgery for varicose veins were compared with those obtained from patients undergoing other surgical procedures ('normals'). Varicose veins had a lower breaking strength and breaking energy than normal veins. Elastic stiffness was less in normals (tan theta = 41 (24] than in varicose veins (tan theta = 55 (18); P less than 0.01). There was no difference in viscoelastic behaviour between samples taken above, at, or below the valve leaflet insertion. In normals, perivalvular vein wall exhibited a 50 per cent lower breaking strength and elastic stiffness than vein from other sites. Collagen content was significantly higher in normal vein specimens in all sites examined (mean collagen content = 70 (21) micrograms/mg, versus 51 (20) micrograms/mg for varicose veins; P less than 0.001). We conclude that significant structural changes are seen in varicose veins. In normal veins, the perivalvular vein wall has distinct viscoelastic features when compared with vein wall from other sites. This difference was not found in veins which became varicose.

Collagen↗

Does local therapy affect survival rates in breast cancer?

BACKGROUND: The goal of this study was to challenge the hypothesis that local recurrence of breast cancer does not affect survival rates, by determining whether survival rates differ for conservative and radical surgical policies. METHODS: This study used prospective long-term follow-up monitoring of two contemporaneous groups of patients, within a single unit, who were treated identically except for the one variable of local treatment policy, i.e., conservative or radical. A total of 451 patients with operable breast cancer were chosen from 567 consecutive patients with breast cancer who were treated between 1970 and 1979 in the University Department of Surgery. The rate of survival 132 months after treatment was used as an outcome measure. RESULTS: Two hundred forty-one patients were treated using a conservative approach and 210 were treated using a radical approach. At 132 months, the survival rate (58% vs. 42%) and median survival time (> 132 vs. 100 months) were significantly improved for the radically treated group (P < .01). The treatment groups were comparable in terms of age, menopausal status, tumor size, histologic grading, and Nottingham Prognostic Index values. The advantage of the radical policy persisted when examined in relation to each of these prognostic factors. CONCLUSIONS: Use of radical local treatment yielded a highly significant survival benefit (comparable to that obtained with adjuvant therapy), compared with a conservative approach. This was related to a reduced locoregional recurrence rate and provides evidence that local therapy influences long-term outcomes for patients with breast cancer. High-quality locoregional control should be emphasized, as is systemic therapy, in management policies. Assessment of surgical techniques, particularly in relation to locoregional recurrence rates, should be included in all studies in which surgery is a component of therapy.

Axilla↗

Know how. A guide to medical photography.

A medical photograph can transfer more information to a health professional than subjective descriptions, which are open to misinterpretation. For the best photographic results, a medical photographer should be used. However, in small hospitals, or in the community, this is not always practicable, therefore nurses should have some knowledge of the most appropriate equipment to use, and know the techniques to employ to attain consistent results. Consistency is one of the most important aspects of medical photography as it allows for comparisons between photographic images over time.

Humans↗