In search of better shape in mastopexy and reduction mammoplasty

"Bottoming out" of parenchyma after several months is a problem extant in previous techniques of mastopexy and reduction mammaplasty. The authors have addressed this problem by creation of a mobile, chest wall-based flap of breast tissue that is passed under and held in place by a loop of pectoral muscle. Experience with this technique spans a period of 7 years and includes 390 patients, indicating the permanence of this correction.     

In search of a function for centrins

Spindle pole bodies, basal bodies and centrosomes are morphologically quite different structures that nevertheless perform similar microtubule-organizing functions in diverse cell types. The recent discoveries that both centrins and gamma-tubulin are common components of these structures suggest a molecular basis for their common functions. The role of centrins is just beginning to be investigated. These filament-associated proteins bind Ca2+. The filaments contract at least in certain circumstances by an ATP-independent mechanism. However, yeast centrin is clearly involved in the duplication of the spindle pole body. A common molecular mechanism may underlie these two apparently different functions.     

In search of morphogenes

May we talk about morphogenes as it is actually done about oncogenes? The author reviews some recent experimental discoveries which launch embryology on a new way: rethinking mitosis, studying cell movement and adhesion, neuronal migration, the role of gap-junctions, cell-death programmation. Embryology and genetics are today converging on identic aims, particularly in the fields of the homeotic genes and of transgenic animals.     

Effect of calcium channel blocker (diltiazem) on platelet aggregation

Platelet aggregation with collagen, ADP and sodium arachidonate was significantly inhibited by 0.48 and 0.24 mg/ml of diltiazem but no significant effect occurred with 0.024 mg/ml of diltiazem. It is suggested that the antiplatelet property of diltiazem may be utilized in clinical setting and diltiazem may be tried synergistically with other antiplatelet drugs.     

BN52021, a platelet activating factor antagonist, is a selective blocker of glycine-gated chloride channel

We have found that the platelet activating factor antagonist (BN52021) is an effective blocker of the glycine (Gly) receptor-mediated responses in the hippocampal pyramidal neurons of rat. Using the whole-cell voltage clamp and concentration clamp recording techniques, we investigated the mechanism underlying the inhibitory action of this terpenoid on the glycine-induced chloride current. BN52021 selectively and reversibly inhibits glycine current in a non-competitive and voltage-dependent fashion. The antagonistic effect of this substance is more pronounced at positive membrane potentials. At holding potential −70 mV and in the presence of 200 μM glycine IC₅₀ value for the blocking action of BN52021 was 270±10 nM. Repetitive applications of BN52021 reveal the use-dependence of its blocking action. When co-applied with strychnine (STR), a competitive glycine receptor antagonist, BN52021 does not alter the IC₅₀ value for strychnine. The inhibitory effect of BN52021 on gamma-aminobutyric acid (GABA) current is at least 25 times less potent than the effect on glycine current. This substance fails to affect AMPA and NMDA responses. It may be concluded that BN52021 inhibits glycine-gated Cl⁻ channels by interacting with the pore region and does not compete for the strychnine-binding centre.