Given a passage with a context and an answer, construct a question on the basis of the information present in the passage. Construct the question in such a way that (i) it is unambiguous, (ii) it is answerable from the passage, (iii) its answer is unique (iv) it answer uses text phrases from the passage. Avoid creating questions that (i) can't be answered correctly without actually understanding the passage and (ii) uses the same words or phrases given in the passage.

[Q]: Context: Smoking cessation rapidly reduces cardiovascular risk. The pathophysiological mechanisms involved are still being debated. We measured structural and functional arterial wall properties of the femoral and carotid arteries after smoking cessation to investigate their possible role in cardiovascular risk reduction.', 'Out of 127 smokers, 33 proved to stop smoking for two years. They were compared with 50 nonsmokers and 55 persistent smokers in a prospective study. Cross-sectional compliance and distensibility coefficients as well as intima-media thickness of both carotid arteries and of the right common femoral artery were measured ultrasonographically at baseline and 3, 6, 12 and 24 months after smoking cessation. The nonsmoking and persistent smokers group were measured twice at an interval of 24 months.', 'Persistent smoking and two years of smoking cessation did not affect cross-sectional compliance and distensibility coefficients. Although at baseline intimal-medial layers were thicker in smokers, the change over time in intima-media thickness did not differ significantly between all three groups.
Answer: Two years of smoking cessation was not accompanied by a slower progression or a regression in intima-media thickness nor by an improved cross-sectional compliance or distensiblity coefficient. Nevertheless, smoking cessation should be recommended as it reduces cardiovascular risk rapidly after smoking cessation.
[A]: Does two years of smoking cessation reduce arterial wall thickness and stiffness?


[Q]: Context: Immunohistochemistry (IHC) is a well-established, widely accepted method in both clinical and experimental parts of medical science. It allows receiving valuable information about any process in any tissue, and especially in bone. Each year the amount of data, received by IHC, grows in geometric progression. But the lack of standardization, especially on the post-analytical stage (interpreting and reporting of results), makes the comparison of the results of different studies impossible.', 'Comprehensive PubMED literature search with a combination of search words "immunohistochemistry" and "scoring system" was performed and 773 articles describing IHC results were identified. After further manual analysis 120 articles were selected for detailed evaluation of used approaches.', 'Six major approaches to the interpretation and presentation of IHC analysis results were identified, analyzed and described.
Answer: The overview of the existing approaches in evaluation and interpretation of IHC data, which are provided in the article, can be used in bone tissue research and for either better understanding of existing scoring systems or developing a new one. Standard multiparametric, semiquantitative IHC scoring systems should simplify and clarify the process of interpretation and reporting of received data.
[A]: Does different approaches for interpretation and reporting of immunohistochemistry analysis result in the bone tissue - a review?


[Q]: Context: Complement protein C4d has been used as a marker of antibody mediated rejection in kidney allografts. C4d has been shown to be deposited also in chronic kidney allograft rejection, and frequently in acute liver allograft rejection. In chronic liver allograft rejection there is limited data of C4d positivity.', '7 liver allografts explanted at retransplantation due to chronic rejection were examined for expression of C4d. Immunoperoxidase technique on frozen sections was used. The "zero" biopsies of the same livers at the first transplantation served as controls.', 'Expression of C4d was significantly increased in portal and central veins as well as in the portal stroma of the grafts with chronic rejection when compared to the expression at implantation of the graft.
Answer: The complement system and anti-donor antibodies may contribute to the process of chronic allograft rejection in the liver.
[A]:
Is vascular deposition of complement C4d increased in liver allografts with chronic rejection?