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We demonstrate that PdAu single-atom alloy model catalysts offer a heterogeneous route to selective Würtz-type C-C coupling. Specifically, when methyl iodide is exposed to an otherwise unreactive Au(111) surface, single Pd atoms in the surface layer promote C-I dissociation and C-C coupling, leading to the selective formation of ethane.

Previously, we demonstrated that inhibition of proteasomal chymotrypsin-like (CT-like) activity in human prostate cancer (PCa) PC-3 cultures and PC-3 xenografts results in accumulation of ubiquitinated proteins, followed by induction of cell death. Studies have shown that plasma CT-like proteasomal activity may be a powerful biomarker for risk stratification in hematologic malignancies. We hypothesized that circulating proteasomes could also be used to stratify risk for patients with PCa. A total of 109 patients with suspected PCa underwent prostatic biopsies were enrolled. Subjects were divided into non-cancer, low-risk PCa, and high-risk PCa groups. Three different proteasomal activity markers (CT-like, caspase-like, and trypsin-like) were measured and compared among the three groups. The proteasomal target proteins, Ub-prs, Hsp70, Bax, and P27 in plasma and prostate tissues were also evaluated. Multivariate analysis was used to assess whether CT-like activity was a predictor of PCa progression. Only proteasomal CT-like activity in the high-risk group was statistically higher than in the non-cancer group (P < 0.05). The expression of Ub-prs, Hsp70, Bax, and P27 protein was decreased in both plasma and PCa tissue of high-risk patients. CT-like activity was found to be an independent predictor of high-risk PCa. Subjects with CT-like activity ≥55 had a 2.15-fold higher risk of having high-risk PCa as compared to those with a CT-like activity of <55 (P = 0.021). We found CT-like activity to be an independent predictor of high-risk PCa, and as such, it may be a good candidate as a biomarker for high-risk PCa detection and stratification.

Chinese men should have a higher prostate-specific antigen (PSA) "gray zone" than the traditional value of 2.5-10.0 ng ml-1 since the incidence of prostate cancer (PCa) in Chinese men is relative low. We hypothesized that PSA density (PSAD) could improve the rate of PCa detection in Chinese men with a PSA higher than the traditional PSA "gray zone." A total of 461 men with a PSA between 2.5 and 20.0 ng ml-1 , who had undergone prostatic biopsy at two Chinese centers were included in the analysis. The men were then further divided into groups with a PSA between 2.5-10.0 ng ml-1 and 10.1-20.0 ng ml-1 . Receiver operating characteristic (ROC) curve was used to evaluate the efficacy of PSA and PSAD for the diagnosis of PCa. In men with a PSA of 2.5-10.0 ng ml-1 or 10.1-20.0 ng ml-1 , the areas under the ROC curve were higher for PSAD than for PSA. This was consistent across both centers and the cohort overall. When the entire cohort was considered, the optimal PSAD cut-off for predicting PCa in men with a PSA of 2.5-10.0 ng ml-1 was 0.15 ng ml-1 ml-1 , with a sensitivity of 64.4% and specificity of 64.6%. The optimal cut-off for PSAD in men with a PSA of 10.1-20.0 ng ml-1 was 0.33 ng ml-1 ml-1 , with a sensitivity of 60.3% and specificity of 82.7%. PSAD can improve the effectiveness for PCa detection in Chinese men with a PSA of 2.5-10.0 ng ml-1 (traditional Western PSA "gray zone") and 10.1-20.0 ng ml-1 (Chinese PSA "gray zone").

The prostate-specific antigen (PSA) "gray zone" in Chinese men is likely higher than the traditional value (2.5-10.0 ng/ml) since the incidence of prostate cancer in Chinese men is relative low. The utility of percent free PSA in predicting prostate cancer is based on Western populations and may introduce sizable bias when applied to a Chinese cohort. We assessed the efficacy of percent free PSA in predicting prostate cancer in Chinese men with a PSA of 2.5-10.0 and 10.1-20.0 ng/ml. A total of 558 men with a PSA of 2.5-20.0 ng/ml who had undergone prostatic biopsy to detect prostate cancer from two Chinese centers were included. The rates of prostate cancer in different percent free PSA ranges were evaluated. Receiver operating characteristic curve (ROC) was used to evaluate and compare the efficiency of PSA and percent free PSA in the diagnosis of prostate cancer. The areas under ROC (AUCs) for percent free PSA for predicting prostate cancer were not higher than those for PSA, although prostate cancer detection rates increased with decreased percent free PSA in men with a PSA of 2.5-10.0, 10.1-20.0, and 2.5-20.0 ng/ml. Similarly, for men aged <70 and ≥ 70 years and with prostate volume <40 and ≥ 40 ml, AUCs showed percent free PSA was not better than PSA in predicting prostate cancer. By analyzing multicenter data, we first found that percent free PSA does not improve detection of prostate cancer in Chinese men with a PSA of 2.5-10.0 or 10.1-20.0 ng/ml.

Prostate volume (PV) has been shown to be associated with prostate cancer (PCa) detection rates in men with a prostate-specific antigen (PSA) in the 'grey zone' (2.0-10.0 ng ml(-1)). However, the PSA 'grey zone' in Asian men should be higher because the incidence of PCa in Asian men is relatively low. Therefore, we evaluated the association between PV and PCa detection rates in men with PSAs measuring 10-50 ng ml(-1). Men who underwent a 13-core prostatic biopsy with PV documentation participated in the study. A multivariate stepwise regression was used to evaluate whether the PV at time of prostate biopsy could predict the risk of PCa. The rates of PCa among men in different PSA ranges, stratified by PV medians (<60 and ≥60 ml), were calculated. There were 261 men included in the final analysis. PV was the strongest predictor of PCa risk (odds ratio, 0.02; P<0.001) compared to other variables. The PCa rates in men with PVs measuring <60 and ≥60 ml in the 10-19.9 ng ml(-1) PSA group were 40.6% and 15.1%, respectively, while the rates for men with PSAs measuring 20-50 ng ml(-1) were 65.1% and 26.8%. PV is an independent predictor of PCa in men with PSA measuring 10-50 ng ml(-1). In clinical practice, particularly for those countries with lower incidences of PCa, PV should be considered when counselling patients with PSAs measuring 10-50 ng ml(-1) regarding their PCa risks.

Nomograms for predicting the risk of prostate cancer developed using other populations may introduce sizable bias when applied to a Chinese cohort. In the present study, we sought to develop a nomogram for predicting the probability of a positive initial prostate biopsy in a Chinese population. A total of 535 Chinese men who underwent a prostatic biopsy for the detection of prostate cancer in the past decade with complete biopsy data were included. Stepwise logistic regression was used to determine the independent predictors of a positive initial biopsy. Age, prostate-specific antigen (PSA), prostate volume (PV), digital rectal examination (DRE) status, % free PSA and transrectal ultrasound (TRUS) findings were included in the analysis. A nomogram model was developed that was based on these independent predictors to calculate the probability of a positive initial prostate biopsy. A receiver-operating characteristic curve was used to assess the accuracy of using the nomogram and PSA levels alone for predicting positive prostate biopsy. The rate for positive initial prostate biopsy was 41.7% (223/535). The independent variables used to predict a positive initial prostate biopsy were age, PSA, PV and DRE status. The areas under the receiver-operating characteristic curve for a positive initial prostate biopsy for PSA alone and the nomogram were 79.7% and 84.8%, respectively. Our results indicate that the risk of a positive initial prostate biopsy can be predicted to a satisfactory level in a Chinese population using our nomogram. The nomogram can be used to identify and counsel patients who should consider a prostate biopsy, ultimately enhancing accuracy in diagnosing prostate cancer.