Caffeine is a major ingredient of daily beverages including coffee, tea, coca-cola, et al, as well as one of most widely used drugs in the world. Caffeine is the stimulant of central nervous system and has positive effect on cardiovascular system. Moreover, it is able to promote secretion of gastric acid and alleviate migraine. It also play the wide-ranging roles in the other systems of the body. So, making a thorough investigation on caffeine not only has clinical significances, but also give a beneficial guide to the health and life. This review aims at highlighting the pharmacological effects of caffeine and exploring the relationship between the body and caffeine.

Objective: To study the relationship between the whole blood zinc concentration and prostate carcinoma and to explore the diagnostic value of the whole blood zinc concentration combined with blood serum prostate specific antigen (PSA) for prostate cancer. Methods: A total of 95 patients with prostate carcinoma and 91 patients with benign prostate hyperplasia were selected between July 2005 and October 2008 in Zhongda Hospital of Southeast University and The Affiliated Drum Tower Hospital of Nanjing University Medical School. The whole blood zinc concentration was analyzed by atomic absorption spectometry. The serum PSA was analyzed by radioimmunoassay. Results: The volumes of the whole blood zinc concentration were 4.73±1.51 μg/mL in the prostate carcinoma group and 6.82±1.63 μg/mL in the benign prostate hyperplasia group, with a significant difference between the two groups (P＜0.001). The serum PSA general distribution was significantly different between the two groups (P＜0.01). There was no significant difference in the serum PSA of 4.0 to 10.0 ng/mL between the two groups (P=0.14). Compared with that in the benign prostate hyperplasia group, the area under ROC curve for the whole blood zinc concentration in the prostate carcinoma group was 0.82. The diagnostic accuracy was optimal with 5.24μg/mL set as the cut-off value of the whole blood zinc concentration and the Youden's index was 0.46 when it was combined with serum PSA 4.0 ng/mL (connection in series). The specificity was 75%, up to 2.34 times of serum PSA applied alone. Meanwhile, the Youden's index was 0.51, achieving 2.22 times. It was not helpful for the diagnosis of prostate carcinoma that the two diagnostic tools were in parallel by which the Youden's index was only 0.14. Conclusion: Detection of the whole blood zinc concentration is beneficial for differentiation of prostate carcinoma from benign prostate hyperplasia. Combined with serum PSA (connection in series), it can significantly impove diagnostic efficiency when PSA was 4.0～10.0ng/mL. Detection of the whole blood zinc concentration can provide valuable information for the diagnosis of prostate cancer and worths clincal application.