There are two phenotypically distinct subpopulations of mast cells in rodents: connective tissue-type mast cells (CTMC) and mucosal mast cells (MMC). These populations differ in their location, cell size, staining characteristics, ultrastructure, mediator content and T-cell dependency. Several investigators recently reported a further subclass of mast cells which arise when normal mouse haematopoietic cells are cultured with interleukin-3 (IL-3); IL-3 is an activity similar or identical to mast-cell growth factor, histamine-producing factor, or P-cell stimulating factor. These cultured mast cells are in many ways similar to MMC; they stain with Alcian blue but not safranin, contain chondroitin sulphate E proteoglycan rather than heparin proteoglycan and have relatively low histamine content, as do MMC. Although proliferation of MMC is known to be T-cell dependent in vivo and thought to be IL-3-dependent in vitro, the factors on which CTMC proliferation depends remain elusive. Here we show that mature CTMC purified from mouse peritoneal cells can proliferate in vitro in methylcellulose culture and maintain the appearance and function of CTMC. We also present evidence that mature CTMC cannot proliferate in the presence of pure IL-3 alone.

Animals↗

PubMedDate not supplied

Phenotype i associated with congenital cataract in Japanese.

A Japanese family with two siblings of phenotype i is presented. Both had a past history of surgical treatment for congenital cataract. In Japan, 18 individuals of phenotype i, including our case, have been found in ten unrelated families. Seventeen of them had congenital cataract. Cataract was not found in any of the 45 phenotype I members in these families. It is briefly discussed why these two linked and quite rare genes were found in combination only in Japanese persons.

Cataract↗

PubMedDate not supplied

Vasovagal reactions in blood donors.

The donor records of a hospital blood bank, analyzed from a statistical standpoint demonstrated a low incidence of vasovagal reactions: 119 in 10,547 donations (1.13%). Donors of younger age and of lower diastolic blood pressure were more prone to reaction. There was no significant sex difference. Higher reaction rates were also associated with first-time donation, the time of year (spring), and a particular phlebotomist. The low reaction rate and the clearly demonstrated psychologic factors in the present study were attributed to a reflection of the small amount (200 ml) of blood withdrawn. The importance of the phlebotomist-donor relationship was stressed.

Adult↗

PubMedDate not supplied

Factors influencing yield of plateletpheresis by discontinuous centrifugation.

Plateletphereses performed by the Haemonetics Model 30 Blood Processor under a fixed condition were retrospectively analyzed. The mean platelet yield was 5.97 X l0 (ll) (+/- l.46 X l0 (ll). Prepheresis platelet count was significantly correlated to platelet yield (p less than 0.001), but hematocrit was not (p greater than 0.1). Blood-drawing time showed a significant correlation (p less than 0.01) and may suggest than an infusion rate of 60 ml/minute is a technique of choice. A large number of platelets (% platelet recovery = 73.0 +/- l4.l%) was discarded in order to remove erythrocytes and leukocytes from the initial product. The recovery was negatively correlated to the percentage removal of leukocytes (p less than 0.01), which means that a platelet product of good quality not containing leukocytes can be prepared at the sacrifice of a large quantity of platelets. It is desirable to devise a simple and practical technique to obtain pure platelets without loss.

Bloodletting↗