instruction:
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).
question:
Abstract: Fibroblasts from two affected members of a large pedigree in which osteogenesis imperfecta (OI) type IV is genetically linked to the pro alpha 2(I) gene of type I collagen synthesize two populations of pro alpha 2(I) chains. One population is normal; the second population appears to have a deletion of about 10 amino acid residues from the middle of the triple helical domain. The mutation in pro alpha 2(I) causes increased posttranslational modification in the amino-terminal half of some pro alpha 1(I) chains, lowers the melting temperature of type I collagen molecules that incorporate a mutant pro alpha 2(I) chain, and prevents or delays the secretion of those molecules from fibroblasts in cell culture. On the basis of this study and linkage studies in additional families, it appears that the OI type IV phenotype is often the result of heterozygosity for mutations in pro alpha 2(I) that alter the triple helical structure of type I collagen.
Which is the apt title for the abstract? option1: Osteogenesis imperfecta type IV. Biochemical confirmation of genetic linkage to the pro alpha 2(I) gene of type I collagen. option2: Case records of the Massachusetts General Hospital. Weekly clinicopathological exercises. Case 48-1986. A 20-year-old Cambodian immigrant with systemic lupus erythematosus and respiratory distress.
answer:
Osteogenesis imperfecta type IV. Biochemical confirmation of genetic linkage to the pro alpha 2(I) gene of type I collagen.

question:
Abstract: Human decompression sickness is presumed to result from excess inert gas in the body when ambient pressure is reduced. Although the most common symptom is pain in the skeletal joints, no direct study of nitrogen exchange in this region has been undertaken. For this study, nitrogen tagged with radioactive 13N was prepared in a linear accelerator. Nine human subjects rebreathed this gas from a closed circuit for 30 min, then completed a 40- to 100-min washout period breathing room air. The isotope 13N was monitored continuously in the subject's knee during the entire period using positron detectors. After correction for isotope decay (half-life = 9.96 min), the concentration in most knees continued to rise for at least 30 min into the washout period. Various causes of this unexpected result are discussed, the most likely of which is an extensive redistribution of gas within avascular knee tissues.
Which is the apt title for the abstract? option1: Nitrogen gas exchange in the human knee. option2: Patient and house officer attitudes on physician attire and etiquette.
answer:
Nitrogen gas exchange in the human knee.

question:
Abstract: Histopathologic studies of dermal dog bites revealed changes identical with those observed in distant gunshot skin entrance wounds and in a presternal skin stab wound made by a screwdriver. The similarity of the epithelial and collagen changes produced by these three totally different traumatizing, perforating agencies indicate that it is the bullet's penetrating and crushing power, and not its caloric content, that is responsible for the characteristic dermal collagen changes noted in these common injuries.
Which is the apt title for the abstract? option1: Bullet or bite--a contribution to the morphogenesis of gunshot dermal injury. option2: Functional recovery after decompressive operation for thoracic and lumbar spine fractures.
answer:
Bullet or bite--a contribution to the morphogenesis of gunshot dermal injury.