Given an abstract of a paper, generate a title for this paper such that conveys the key focus of the paper.

Abstract: During liquid preservation under blood bank conditions, red cell membranes inexorably undergo damage that decreases erythrocyte survival after transfusion. Accordingly, we have surveyed membrane skeletal protein interactions during storage. We uncovered a decrease in the in vitro formation of spectrin-actin complex in the absence (50%) or presence (60%) of protein 4.1. Actual formation of the spectrin-actin-protein 4.1 complex fell in a linear fashion during the storage period. This fall in spectrin-actin interaction tightly correlated with the decline in total red cell phospholipid (R = 0.9932) measured simultaneously. This decrement of spectrin-actin association could be restored to greater than 70% of normal values by preincubation of stored spectrin with 50 mM dithiothreitol. This storage injury to spectrin-actin interaction might weaken the membrane skeleton and lead to decreased red cell survival. In vitro reversibility of the damage by reducing agents suggests a possible new direction for prolonging the shelf life of stored blood.
Molecular defect in the membrane skeleton of blood bank-stored red cells. Abnormal spectrin-protein 4.1-actin complex formation.

Abstract: Seventy-five patients, 80-90 years old, each having approximately three associated diseases, underwent a total of 104 gastrointestinal endoscopies. Of these, 73 were upper (29 emergencies) and 31 lower endoscopies (21 were rigid sigmoidoscopies). There were two very mild short-lived complications; vomiting and bleeding. We found 16 gastric ulcers, 16 duodenal or pyloric ulcers, and 11 cases of esophagitis. Bleeding duodenal (8) or gastric (4) ulcers and polyps or malignant tumors (7) were seen less often. In 34 of 68 lesions the endoscopic and x-ray findings were the same. In the other 34 there were 10 endoscopic failures to identify colonic diverticula, hiatus hernia, and gastroesophageal reflux that were seen radiologically. In 24 patients, diagnoses were not made radiologically, but were recognized at endoscopy. The safety and accuracy of endoscopy in the old and sick does not differ from that in younger patients.
Gastrointestinal endoscopy in octagenarians.

Abstract: Differences in aortic impedance between normotensives and hypertensives are not well characterized. We examined impedance in 8 normotensive and 11 hypertensive (mean 96.7 vs. 122.2 mmHg) age-matched, Chinese patients undergoing cardiac catheterization at rest, during nitroprusside, and handgrip exercise before and after beta blockade (propranolol). Hypertensives had higher resistance (2,295 vs. 1713 dyn-s/cm5), characteristic impedance (145.7 vs. 93.9 dyn-s/cm5), total external power (1,579 vs. 1174 mW), peripheral reflections (ratio of backward to forward wave components of 0.54 vs. 0.44), and first zero crossing of impedance phase angle (4.15 vs. 2.97 Hz). These abnormalities were eliminated with vasodilatation. Differences between groups were not further exacerbated when pressure was increased during handgrip exercise. Beta blockade further increased resistance and reflections. Thus, hemodynamic abnormalities of essential hypertension (increased resistance, reflections, and pulse wave velocity, and decreased compliance) are compatible with an increased vasomotor tone that is further unmasked during generalized beta blockade.

Arterial hemodynamics in human hypertension.

