Reflex venomotor responses to lower body negative pressure following endurance training

The effect of endurance training on reflex venomotor control during an orthostatic challenge was investigated in 11 sedentary male volunteers. An exercise (E) group (n = 6) underwent 12 weeks of endurance exercise training, whereas a control (C) group (n = 5) remained sedentary. Training significantly increased VO2max values in E (pre-training: 37.0 +/- 2.5 ml.kg-1.min-1; post training: 44.6 +/- 2.5 ml.kg-1.min-1), while C showed no significant change. During exposures to two levels of lower body negative pressure (-10 and -40 mm Hg), both C and E groups showed similar graded decreases in forearm venous volume (FVV). The magnitude of the FVV decreases did not differ between groups or when comparing pre-training and post-training values. We conclude that the reflex venoconstrictor response to LBNP was not affected by endurance training.     

Management of submucous uterine fibroid with buserelin, gemeprost and hysteroscopic resection

A 19-year-old virgin presented with severe menorrhagia and a haemoglobin level of 76 g/L as a problem of management. A 5 cm diameter submucous fibroid was identified at hysteroscopy and biopsied but was unable to be removed. The luteinising hormone releasing hormone agonist, buserelin, was used in an attempt to produce symptomatic relief. One week after commencing buserelin therapy, severe menorrhagia occurred and the patient was admitted to hospital with a haemoglobin concentration of 24 g/L. Buserelin treatment was continued and no further menstruation occurred over the following year. As the patient was now well, hysteroscopic submucous fibroid resection was contemplated. Due to cervical rigidity in this teenager, a 1 mg gemeprost pessary was inserted into the posterior vaginal fornix three hours before surgery. This allowed an operative hysteroscope to be inserted into the uterus and a fibroid resection to be performed. Menstrual blood loss has been normal for six months after hysteroscopy. A combined medical and surgical approach may avoid hysterectomy in such problem patients.     

Isolation and characterization of an acquired antithrombin antibody

A 68-year-old man, following mitral valve replacement, presented with a low-grade chronic consumptive coagulopathy. Laboratory analysis showed mild fibrinolysis, minimal effect of coumadin therapy, and a prolonged thrombin time (greater than 150 seconds using bovine IIa). When purified human IIa was used the thrombin time normalized to within 17 seconds of controls, suggesting a possible inhibitor of bovine IIa. An anti-IIa antibody was isolated by protein A-Sepharose (Sigma, St Louis, MO) chromatography followed by affinity chromatography using a bovine IIa-Sepharose column. The effects of this purified anti-IIa antibody on both bovine and human IIa procoagulant and anticoagulant functions were studied. The isolated immunoglobulin G (IgG) was observed to inhibit bovine IIa in all assays tested. This IgG was also able to slightly prolong fibrinogen clotting by human IIa. Using an enzyme-linked immunosorbent assay it was observed that the IgG bound to bovine IIa, bovine II, human IIa, but not to human II. Further, binding was detectable at approximately 50-fold lower concentrations to bovine IIa (1 nmol/L IgG concentration) than to human IIa (50 nmol/L IgG concentration). The effect of the antibody on the reaction between IIa and AT III/heparin was investigated. Human IIa was found to be protected from AT III/heparin neutralization in the presence of this antibody. These results suggest that this patient developed an antibody that strongly binds to and inhibits the bovine IIa in all assays tested. However, the antibody only significantly affects human IIa neutralization by AT III/heparin, and has little effect on the human IIa procoagulant activity. These data suggest that the decreased effect of AT III/heparin on this patient's IIa may have been a contributing factor in his coagulopathy. The exact cause of this antibody development is unclear, but the role of bovine topical thrombin used during cardiac valve replacement surgery is suspect.     

Increased risk of squamous cell carcinoma in junctional epidermolysis bullosa

Non-Herlitz junctional epidermolysis bullosa (JEB) is an autosomal recessive genodermatosis characterized by skin fragility and blistering. It is usually caused by mutations in the genes encoding the basement membrane proteins laminin 5 or type XVII collagen. Clinically, impaired wound healing and chronic erosions cause major morbidity in affected patients. Previously it was thought that these individuals, unlike patients with dystrophic EB, did not have an increased risk of developing skin cancer. However, we describe three patients with non-Herlitz JEB (aged 42, 56 and 75 years) who developed cutaneous squamous cell carcinomas (SCCs). The tumours were well-differentiated in two cases, but one patient had multiple primary SCCs that were either well- or moderately differentiated. Most cases of SCC in non-Herlitz JEB described have occurred in those with laminin 5 defects and on the lower limbs. These clinicopathological observations have important implications for the management of patients with this mechanobullous disorder as well as providing further insight into the biology of skin cancer associated with chronic inflammation and scarring.     

MR demonstration of mesencephalic lesions in osmotic demyelination syndrome (central pontine myelinolysis)

Summary A case of CPM/ODS with mesencephalic involvement is presented. The lesions were nonenhancing on CT and were homogeneous and well-defined on MR with prolonged T1- and T2-relaxation times. MR is recommended for imaging the pontomesencephalic demyelinating lesions associated with this disease.