Cimetidine-resistant Zollinger-Ellison syndrome: successful management with ranitidine.

In a patient with the Zollinger-Ellison syndrome who had undergone vagotomy, pyloroplasty and, later, gastrojejunostomy, epigastric pain and stomal ulceration recurred despite the use of high doses (2700 mg/d) of cimetidine. Ranitidine, a new histamine H2-receptor antagonist, reversed all symptoms and healed the stomal ulcer without side effects, thus obviating the need for further surgery. Ranitidine may prove to be the drug of choice in the medical management of patients with the Zollinger-Ellison syndrome.     

Familial DiGeorge syndrome and associated partial monosomy of chromosome 22

Summary Partial monosomy of 22q due to an unbalanced 4;22 translocation was seen in a 2-month-old male with Type I truncus arterious, dysmorphic features, and T-cell abnormalities. The family history revealed a previous sib with Type I truncus arteriosus, thymic aplasia, and parathyroid hypoplasia noted on postmortem examination, consistent with DiGeorge syndrome. Evaluation of the asymptomatic mother of these two patients revealed partial T-cell deficiency and the same unbalanced translocation with deletion of proximal 22qll. These findings provide further evidence that some cases of complete or partial DiGeorge syndrome are associated with monosomy of the proximal long arm of chromosome 22, and they may explain many, if not all, familial cases of the syndrome.Supported in part by National Foundation-March of Dimes Grant No. 2-161/C-331. Funds from the Texas Department of Health through PL94-278 National Genetic Diseases Act, from the Robert J. Kleberg, Jr. Center for Human Genetics, and USPHS Grant No. RR-05425.     

Identification of the milk fat globule membrane proteins. II. Isolation of major proteins from electrophoretic gels and comparison of their amino acid compositions

The fat globule membranes of milk are derived from the apical plasma membrane of the mammary secretory cells. The nature of the membrane proteins, as isolated from cows' milk, has been studied by the use of discontinuous and continuous SDS-gel electrophoresis. Six methods of preparation of milk fat globule membrane suggested by various authors were tested; gel electrophoresis showed that five major bands were present, independent of the method of preparation. The apparent molecular masses of these proteins as determined on SDS-gels (15% T) were 167, 142, 64, 49 and 46 kDa, respectively. The 167 kDa band stained only with periodic acid-Schiff reagent, while the 142 kDa band stained only with Coomassie blue; the last three bands stained with both. Delipidated membranes were extracted stepwise with water, 0.02 M NaCl and 0.6 M NaCl. The 64 kDa band appears to be nearly insoluble, while the bands of 142, 49 and 46 kDa are fractionated by this procedure. The resolution of all of these proteins by electrophoresis was superior to that achieved by molecular sieve chromatography, and so electrophoretic extraction was used to isolate the major proteins. Dansyl chloride derived proteins were used as markers. Amino acid compositions of the recovered proteins were obtained and are compared.     

Alloantiserum-mediated supperssion of Ir gene controlled antigen-induced lymphocyte activation: effect on uridine and leucine incorporation.

Antisera to guinea pig histocompatibility antigens specifically suppress Ir gene-controlled antigen-stimulated, DNA-synthetic responses in vitro. To define further the mechanisms of alloantiserum-mediated suppression and to utilize this suppression as a probe of the cellular events occurring during lymphocyte activation, we have examined the effects of alloantisera on 14C-leucine and 3H-uridine incorporation, earlier events after antigen stimulation. The RNA and protein synthetic responses of peritoneal exudate lymphocytes from immunized guinea pigs to DNP-GL (controlled by a strain 2-linked Ir gene) are 40 to 50% of maximum by 24 hr in culture and at or near maximum by 48 hr. DNA synthesis was only 2% of maximum at 24 hr and maximum at 72 hr. Comparisons of the degree of stimulation of the incorporation of all three precursors reveals an excellent correlation between leucine and uridine but poor correlation between leucine and thymidine. Despite the observed differences in time course of incorporation and magnitude of response, the susceptibility to suppression by alloantisera of all three responses was virtually identical. Anti-2 sera, added at the initiation of culture, completely suppress all three responses. If addition was delayed 8 hr, 50 to 60% suppression was still demonstrated, whereas only minimal suppression was evidenced if addition was delayed 18 hr. These results suggest that by 8 to 10 hr of incubation with antigen, the responding cells have undergone the necessary biochemical and structural changes to eventuate in an immune response; and, furthermore, that alloantisera do not suppress by blocking antigen access to, or release from, its lymphocyte membrane receptor, but rather by a dynamic alteration of the lymphocyte membrane surface which interferes with the stimulus being generated by the antigen-receptor complex.