The mammalian Y chromosome: a new perspective

If pityriasis lichenoides et varioliformis acuta (PLAVA) exists in the vagina or cervical os of the uterus, it may cause premature labor and premature rupture of the membranes.     

Management of otitis media in a high risk population

BACKGROUND: Rural and remote Aboriginal and Torres Strait Islander children have extremely high rates of otitis media and hearing loss. Despite considerable evidence, clinical practice continues to vary. This may be partly related to the failure of recent guidelines to be explicit about which factors should influence decision making. OBJECTIVE: To provide rural and remote GPs caring for young Aboriginal and Torres Strait Islander children with an evidence based guide to the principles that determine the clinical management of otitis media and hearing loss. DISCUSSION: While population health strategies are extremely important, the GP also needs to be able to advise families of affected children of the benefits and risks of the medical, surgical and audiological interventions available. The key to this process is the ability to distinguish between suppurative and non-suppurative disease, and a familiarity with the natural history and the likely hearing loss associated with different disease states in high risk populations.     

A new model for risk stratification and delivery of cardiovascular rehabilitation services in the long-term clinical management of patients with coronary artery disease

A case of multiple dorsal dislocations of the metacarpophalangeal joints is presented with a review of literature. Prompt recognition of the dislocation type is essential, followed by trial of closed reduction under proper anesthesia; open reduction is sometimes required. A short period of immobilization is needed, followed by intensive rehabilitation.     

Mature T cell reactivity altered by peptide agonist that induces positive selection

Recent studies have investigated how defined peptides influence T cell development. Using a T cell receptor-transgenic beta2-microglobulin-deficient model, we have examined T cell maturation in fetal thymic organ cultures in the presence of various peptides containing single-alanine substitutions of the strong peptide agonist, p33. Cocultivation with the peptide A4Y, which contains an altered T cell contact residue, resulted in efficient positive selection. Several in vitro assays demonstrated that A4Y was a moderate agonist relative to p33. Although A4Y promoted positive selection over a wide concentration range, high doses of this peptide could not induce clonal deletion. Thymocytes maturing in the presence of A4Y were no longer able to respond to A4Y, but could proliferate against p33. These studies demonstrate that (a) peptides that induce efficient positive selection at high concentrations are not exclusively antagonists; (b) some agonists do not promote clonal deletion; (c) positive selection requires a unique T cell receptor-peptide-major histocompatibility complex interaction; and (d) interactions with selecting peptides during T cell ontogeny may define the functional reactivity of mature T cells.     

Vincristine disturbs spontaneous firing of the afferent nerve fibre in ampullary electroreceptor organs

Ampullary electroreceptor organs of the catfish were apically exposed to 0.3 mM vincristine in order to investigate the part played by the microtubular system in stimulus transduction. The main effects were repetitive firing of the afferent fibre, a reduction of the mean spontaneous activity and a reduction of the spike amplitude two to four days after exposure to vincristine. The mean sensitivity was less susceptible to vincristine than the spontaneous activity. Since the shape of the frequency curves remained unchanged and similar effects as described above were also observed after denervation, we conclude that vincristine most likely does not affect electroreceptor cell functioning, but causes degeneration of the afferent fibre.