TASK DEFINITION: Given an abstract, indicate which of the provided candidate titles (Option1 and Option2) best describes it (respond with the text of the title, not option1/2).
PROBLEM: Abstract: Since its first isolation, bovine beta-lactoglobulin (BLG) has been an enigma: although it is abundant in the whey fraction of milk, its function is still not clear. The results of the many physicochemical studies on the protein need a structural interpretation. We report here the structure of the orthorhombic crystal form of cow BLG at pH 7.6, at a resolution of 2.8 A. It has an unusual protein fold, composed of two slabs of antiparallel beta-sheet, which shows a remarkable similarity to plasma retinol-binding protein. A possible binding site for retinol in BLG has been identified by model-building. This suggests a role for BLG in vitamin A transport and we have discovered specific receptors for the BLG-retinol complex in the intestine of neonate calves.
Which is the apt title for the abstract? option1: The structure of beta-lactoglobulin and its similarity to plasma retinol-binding protein. option2: Tumor detection with phase-contrast imaging: an evaluation of clinical potential.

SOLUTION: The structure of beta-lactoglobulin and its similarity to plasma retinol-binding protein.

PROBLEM: Abstract: The effects of cimetidine on the healing and recurrence of duodenal ulcers and gastric ulcers were compared. The extent of the acid secreting areas was examined by the endoscopic Congo red methylene blue test. Using the extent of acid secreting areas gastric ulcers were classified into ulcers with and without extensive acid secreting areas. Duodenal ulcers were all associated with extensive acid secreting areas. The gastric acid outputs in the basal state and after maximal stimulation with gastrin were highest in duodenal ulcers, and lowest in gastric ulcers without extensive acid secreting areas. Cimetidine treatment significantly promoted the healing of duodenal ulcers and gastric ulcers with extensive acid secreting areas when compared with placebo, but not of the gastric ulcers without extensive acid secreting areas. Cimetidine also significantly diminished the recurrence of duodenal ulcers, but not gastric ulcers with and without extensive acid secreting areas. These findings indicate that in Japan cimetidine promotes the healing of duodenal and gastric ulcers associated with high gastric acid production and prevents recurrence of duodenal ulcers, but has little or no influence on the healing and recurrence of gastric ulcers associated with low acid secretion.
Which is the apt title for the abstract? option1: Effects of cimetidine on the healing and recurrence of duodenal ulcers and gastric ulcers. option2: Blocking the filter vents of cigarettes [letter]

SOLUTION: Effects of cimetidine on the healing and recurrence of duodenal ulcers and gastric ulcers.

PROBLEM: Abstract: Mixed sequence DNA can exist in two right-handed and one left-handed double helical conformations--A, B and Z. Under conditions of high water activity the B conformation prevails. If the water activity is reduced on addition of salt or organic solvents, transformation occurs to A-DNA or, in DNAs with alternating purine-pyrimidine sequences, to the left-handed Z-DNA. In crystal structure analyses of oligonucleotides, the free oxygen atoms of adjacent phosphate groups along the polynucleotide chain in B-DNA are found at least 6.6 A apart and individually hydrated whereas they are as close as 5.3 A in A-DNA and 4.4 A in Z-DNA, and bridged by water molecules. We suggest that this more economical hydration in A- and Z-DNA compared with B-DNA is the underlying cause of B----A and B----Z transitions.
Which is the apt title for the abstract? option1: DNA conformation is determined by economics in the hydration of phosphate groups. option2: Albumin labeled with Gd-DTPA as an intravascular, blood pool-enhancing agent for MR imaging: biodistribution and imaging studies.

SOLUTION:
DNA conformation is determined by economics in the hydration of phosphate groups.