Higher insoluble fiber intake is associated with a lower risk of prostate cancer: results from the PLCO cohort.

Studies regarding the relationship between fiber intake and prostate cancer (PCa) have conflicting results. Therefore, this study examined the relationship between fiber intake and the risk of PCa by using data from Prostate, Lung, Colorectal, and Ovarian (PLCO) Cancer Screening Trial. A total of 54,336 participants in the United States, consisting of 6,414 patients with PCa, were included in this study. Multivariate Cox regression models were applied to estimate adjusted hazard ratios (aHRs) and corresponding 95% confidence intervals (CIs). Compared with individuals in the lowest quartile, individuals in the highest quartile of insoluble fiber intake had a significantly lower risk of PCa (aHR, 0.87; 95% CI, 0.78-0.98). By contrast, no significant associations were detected between total fiber intake (aHR, 0.90; 95% CI, 0.80-1.01) or soluble fiber intake (aHR, 0.90; 95% CI, 0.80-1.02). Subgroup analyses showed that insoluble fiber was related to a decreased risk of PCa in subjects with the following characteristics: age > 65 years, nonsmoking or former smokers, education level ≤ high school, non-Hispanic white ethnicity, or without a family history of PCa. In addition, significant combined effects of insoluble fiber intake, age and family history of PCa on the risk of PCa were observed, but no combined effects of smoking status and insoluble fiber intake were observed. In addition, total fiber, insoluble fiber, and soluble fiber intake had no influence on the mortality of PCa patients. These results show that all 3 measures of fiber suggest a protective association, but insoluble fiber may have a stronger association with the risk of PCa. Future studies are warranted to further investigate these relationships.

Expression of matrix metalloproteinases and their tissue inhibitors in the serum and cerebrospinal fluid of patients with HIV-1 infection and syphilis or neurosyphilis.

The potential mechanisms for altered matrix metalloproteinase (MMP) or tissue inhibitors of matrix metalloproteinase (TIMP) function in patients with syphilis and HIV-1 co-infection (HIV-S) was unclear. To determine the expression of MMP-2, 9 and TIMP-1, 2, 4 in the serum and cerebrospinal fluid (CSF) of HIV-S patients, a total of 20 HIV-S patients and 8 controls were enrolled in a HIV-1 clinical cohort for diagnosis of neurosyphilis in Taiwan. Serum and CSF concentrations of MMP-2, 9, and TIMP-1, 2, 4 were determined by ELISA. Gelatin zymography was used to detect the expression of MMP-2 and MMP-9 in the CSF. Neurosyphilis was defined as a CSF white blood cell count ≥ 20 cells/µL or a reactive CSF Venereal Disease Research Laboratory (VDRL). All the patients with HIV-S were males. Most (85%) had sex with men (MSM) and serum rapid plasma reagin (RPR) titers of ≥ 1:32. The median age was 35 years (IQR 30-43). The median CD4 T cell counts at the time of the diagnosis of syphilis were 270 cells/µL (IQR 96-484). Ten patients (50%) had neurosyphilis based on a reactive CSF VDRL test (n=8) or increased CSF white cell counts ≥ 20/µL (n=2). The concentrations of CSF MMP-9, TIMP-1, and TIMP-2 were significantly higher in patients with HIV-S than the controls (P<0.05). The CSF TIMP-4 concentrations were significantly lower in those with HIV-S (452 pg/ml) than controls (3101 pg/ml), P<0001. There were no significant differences in serum concentrations between the groups. The only finding that distinguished HIV-1 patients with from those without neurosyphilis is a significant higher expression of CSF MMP-9. In conclusion, the MMP/TIMP system was found to be dysregulated in patients with HIV-S regardless of whether they met the laboratory definition of neurosyphilis. The CSF level of MMP-9 was the only measure that distinguished those with or without neurosyphilis.