Biocompatibility of electrospun human albumin: a pilot study

Albumin is rarely used for electrospinning because it does not form fibres in its native globular form. This paper presents a novel method for electrospinning human albumin from a solution containing pharmaceutical grade protein and 25% polyethylene oxide (PEO) used as the fibre-forming agent. After spontaneous cross-linking at body temperature, with no further chemicals added, the fibres become insoluble and the excess PEO can be washed out. Albumin deposited along the fibres retains its native characteristics, such as its non-adhesiveness to cells and its susceptibility for degradation by macrophages. To demonstrate this we evaluated the mechanical properties, biocompatibility and biodegradability of this novel product. After subcutaneous implantation in mice, albumin mats were completely resorbable within six days and elicited only a limited local inflammatory response. In vitro, the mats suppressed cell attachment and migration. As this product is inexpensive, produced from human pharmaceutical grade albumin without chemical modifications, retains its native protein properties and fulfils the specific requirements for anti-adhesive dressings, its clinical use can be expedited. We believe that it could specifically be used when treating paediatric patients with epidermolysis bullosa, in whom non-healing wounds occur after minor hand injuries which lead to rapid adhesions and devastating contractures.

Use of the Accordion Severity Grading System for negative outcomes of carpal tunnel syndrome

A universal classification of the negative outcomes of carpal tunnel release surgery does not, as yet, exist. In order to avoid the use of arbitrary factors we have applied the Accordion Severity Grading System, which uses rigorously defined qualitative terms to classify complications. It also provides a uniform manner for grading the severity of complications, enabling outcome comparisons between centres. We analysed the negative outcomes of 500 device-assisted carpal tunnel releases performed over a 2-year period in the author's department. In order to establish a standardised list of complications we used the terms employed within the guidelines of the American Academy of Orthopaedic Surgeons. Most of these terms were subsequently defined using the data variables and definitions taken from the American College of Surgeons National Surgical Quality Improvement Program or the Medical Subject Headings of the National Library of Medicine. We also adopted the quantitative severity weighting, as proposed by the Accordion system, in order to determine the postoperative morbidity index for our assisted carpal tunnel releases. The most common complications were pain and reversible damage to peripheral nerves. Other common negative events, other than complications, included hand weakness, which we classified as a sequela of the procedure, and incomplete retinaculum release, which we classified as failure to cure. The overall postoperative morbidity index for complications was 0.014. Although the Accordion system was developed for more complex procedures, it may also be adopted for carpal tunnel release surgery where it provides an objective and universal method for the classification of complications.

p63 expression during normal cutaneous wound healing in humans

p63, a recently identified member of the p53 family, was shown to play a role in morphogenesis and, probably, in tumors of keratinocyte origin. Because p63 seems to be a marker of keratinocytes with a high proliferative potential, the expression of this protein was studied along with another marker of cell proliferation, Ki67, during normal epidermal regeneration in humans. Serial biopsies of human skin healing by a secondary intention were taken at various time intervals (between days 2 and 21 after the injury) and were studied immunohistochemically with the use of a 4A4 monoclonal antibody against the DeltaNp63 variant and MM1 monoclonal antibody against the Ki67 antigen. In the normal and injured skin, the expression of the DeltaNp63 protein was restricted to the epidermal keratinocytes and hair follicle keratinocytes. In the first days of the healing process, there was a dramatic down-regulation of both DeltaNp63 and Ki67 expression in the area of the epidermal tongue invading under the crust. Five days after the injury, induction of DeltaNp63 in the basal keratinocytes could be detected, followed by a gradual increase of its expression in subsequent days. Several days after complete wound closure, DeltaNp63 was still strongly expressed not only in the basal keratinocytes but also in the entire spinous layer, whereas the Ki67 expression was restricted to single cells in the basal layer. The results indicate that DeltaNp63 could be involved in the control of physiologic processes, such as cell proliferation and migration, related to epidermal repair during healing of normal skin in humans.

[Myocutaneous flaps: some remarks on genesis of the method]

A history, actual development and clinical applications of a new plastic operation with myocutareous flaps are discussed.

The origins of the concept of muscle flaps

Contrary to contemporary opinion, the principles of muscle flap preparation and the use of muscle flaps for, among other conditions, chronic osteomyelitis were described in Europe in the 19th century. This article introduces significant works from the turn of the century which would have greatly contributed to today's knowledge had they not fallen into obscurity.

[Pseudoaneurysm after anastomosis of a prosthesis with the femoral artery]

One of the complications of femoral artery synthetic prostheses are anastomotic aneurysms. In 1985-1993, 38 patients were treated for anastomotic aneurysms. Diagnosis was based on clinical and ultrasound examinations. A retrospective analysis has shown an occurrence of fever in 12 patients, and superficial pus oozing in 10 patients. Bacteriological cultures of intra-operatively collected specimens were positive in 25 patients. An infection with staphylococci was predominating. Repeated reconstructive surgery was performed within 6 months to 5 years after the primary one, mean 1.6 years. Aneurysm with the segment of prosthesis was excised and replaced by a fragment of new prosthesis (26 patients) or the vessel after excision of aneurysm was sutured with additional sutures on the whole anastomosis circumference (6 patients). On 7 patients bypass grafting was performed with ligation of vessels supplying anastomotic aneurysm. In all patients flow drainage was used. Positive result of re-operation was achieved in 21 (68.4%) patients. Limb was amputated in 10 cases (26.3%), and 2 patients (5.3%) died. An analysis of the treated patients showed an important role of the anastomotic infection in the anastomotic aneurysms formation. The treatment should include prolonged antibiotic therapy prior to the operation. In case of reoperation possible infection should always be considered.