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).

Abstract: The presence of antibodies to muramyl dipeptide (MDP), an adjuvant structure of streptococcal peptidoglycan, was investigated in patients with acute rheumatic fever (ARF). The detection of these antibodies was done by an enzyme-linked immunosorbent assay with a synthetic multivalent MDP conjugate as an antigen. Sera from 33 of 54 children with ARF had detectable levels of antibodies to MDP at the time of diagnosis. Such antibodies could only be detected in sera from two of 52 healthy children and one of 21 children with acute poststreptococcal glomerulonephritis. The specificity of the antibodies to MDP was demonstrated by inhibition, with free MDP, of binding of the sera to the MDP conjugate. The possible use of these antibodies in the diagnosis of ARF and in screening for safe synthetic muramyl peptides in immunization of humans is discussed.
Which is the apt title for the abstract? option1: Detection of antibodies to muramyl dipeptide, the adjuvant moiety of streptococcal cell wall, in patients with rheumatic fever. option2: Relationship between abnormalities of coagulation and fibrinolysis and postoperative intracranial hemorrhage in head injury.
Detection of antibodies to muramyl dipeptide, the adjuvant moiety of streptococcal cell wall, in patients with rheumatic fever.

Abstract: To summarize the results: Bilirubin removal by hemoperfusion was successfully performed for the first time on a premature infant. The hemoperfusion caused no adverse effects on the clinical state of the infant. The bilirubin removed in 90 min--13 mg--indicates the existence of a large extravascular pool. Hemoperfusion is suggested for bilirubin removal from newborn babies, reducing the need for blood exchange with bank blood.
Which is the apt title for the abstract? option1: Bilirubin removal from a jaundiced premature infant by resin hemoperfusion. option2: The potential role of common dermatologic practice technics in transmitting disease [letter]
Bilirubin removal from a jaundiced premature infant by resin hemoperfusion.

Abstract: Cyclic AMP stimulates HCO3 secretion and Cl self-exchange in rabbit cortical collecting tubule. We found that varying peritubular [Cl] changed the Cl self-exchange rate with saturation kinetics (Km, 3-4 mM). HCO3 secretion also showed saturation kinetics as a function of mean luminal [Cl] (Km, 4-11 mM). Both Cl self-exchange and Cl-HCO3 exchange thus appear to be carrier-mediated. Addition/removal of basolateral HCO3 qualitatively changed Cl and HCO3 transport as expected for Cl-HCO3 exchange, but quantitatively changed Cl absorption more than HCO3 secretion. The diffusive Cl permeability and the transepithelial conductance in the presence of HCO3/CO2 and cAMP were higher than in their absence suggesting that HCO3/CO2 and cAMP together increase a conductive Cl pathway parallel to a 1:1 Cl-HCO3 exchanger. Thus, cAMP not only stimulates the overall process of anion exchange (probably by increasing an electroneutral exchanger and/or a series Cl conductance), but also stimulates a Cl conductance parallel to the exchange process.
Which is the apt title for the abstract? option1: Cyclic adenosine monophosphate-stimulated anion transport in rabbit cortical collecting duct. Kinetics, stoichiometry, and conductive pathways. option2: A prospective study of dehydroepiandrosterone sulfate, mortality, and cardiovascular disease.
Cyclic adenosine monophosphate-stimulated anion transport in rabbit cortical collecting duct. Kinetics, stoichiometry, and conductive pathways.