The development and implementation of a revised municipal bylaw to control environmental tobacco smoke.

A bylaw to regulate the contamination of the environment by tobacco smoke was introduced in the Capital Regional District, Victoria, British Columbia as of January 1st, 1991. This smoking control bylaw rigorously limits smoking in all public premises and restricts size, ventilation and location of designated smoking areas. As of January 1st, 1992 all workplaces in this area have become completely smoke-free. This paper describes the process of developing and implementing a municipal smoking control bylaw. Publicity is essential to raise awareness of the issue and to provide information. Engendering of political and public support and the adoption of an appropriate time line for introduction of the bylaw are also important components of the process. Legislation to control tobacco use has been shown to be an effective component of a comprehensive tobacco reduction strategy. Public health officials are urged to consider the implementation of similar policies to combat the health risks posed by environmental tobacco smoke.

Gel-filtered human platelets. Ultrastructure, function, and role of proteins in inhibition of aggregation by aspirin.

Gel filtration of human platelet-rich plasma (PRP) on columns of Sepharose 2B removed at least 99.85% of the plasma proteins from platelets when a column 10 cm in height was used and a plasma volume 11 to 14% of the gel-bed volume was applied. ADP and ATP levels in gel-filtered platelets (GFP) were not significantly different from those in PRP. By transmission electron microscopy, GFP were indistinguishable from PRP. Gel filtration appears to be a highly satisfactory technique of separating platelets from plasma without modifying structure, function, or contents significantly. The roles of several crude protein fractions in platelet aggregation and aspirin's inhibition of aggregation were examined. Fraction I (mostly fibrinogen) enhanced collagen-induced aggregation of gel-filtered platelets; Fraction V (mostly albumin) was inhibitory. Fraction II (mostly gamma-globulin) or gelatin had no significant effect. Aspirin added to gel-filtered platelets inhibited aggregation by 80%. The addition of mixtures of plasma proteins containing albumin increased albumin's inhibitory effect. Incubation of gel-filtered platelets with aspirin labeled in the carboxyl position resulted in no uptake of the label. In contrast, incubation with acetyl-labeled aspirin was followed by uptake of more than 2 X 10(6) acetyl groups per platelet in 1 minute. Incubation for 30 minutes resulted in a five- to sixfold further increase in uptake of the label. Aspirin can acetylate platelets and inhibit aggregation directly. Plasma proteins, in particular albumin or a contaminant of the albumin fraction tested, enhance the inhibitory effect of aspirin on platelet aggregation.

Ultrastructure of platelets in Bernard-Soulier syndrome.

The platelets of a patient with the Bernard-Soulier syndrome were studied by electron microscopy. The main abnormalities were the presence of giant and often round platelets, hypertrophic and frequently widely dilated open canalicular system, disorganized microtubules, and platelets with sparse or absent granulation. Although well defined, these ultrastructural morphologic aberrations are not considered diagnostic or pathognomonic of the syndrome.