Implementation of a national colorectal cancer screening program

There is no direct evidence that colonoscopy screening reduces mortality from colorectal cancer. However, results from studies using fecal occult blood testing and sigmoidoscopy, along with the fact that colonoscopy is performed after positive primary screening tests, support this assumption. Colonoscopy every 10 years is the preferred strategy in terms of clinical outcomes and cost effectiveness. The purpose of this article is to present the methodology used for the implementation of an opportunistic colonoscopy colorectal cancer screening program in Poland. We also review recent literature on challenges related to colonoscopy screening including recruitment, acceptance, and quality of the procedure.     

Combining areal DXA bone mineral density and vertebrae postero-anterior width improves the prediction of vertebral strength

Objective

Areal bone mineral density (aBMD) measured by dual-energy X-ray absorptiometry (DXA) is an important determinant of bone strength (BS), despite the fact that the correlation between aBMD and BS is relatively weak. Parameters that describe BS more accurately are desired. The aim of this study was to determine whether the geometrical corrections applied to aBMD would improve its ability for BS prediction. We considered new parameters, estimated from a single DXA measurement, as well as BMAD (bone mineral apparent density) reported in the literature.

Materials and methods

In vitro studies were performed with the L3 vertebrae from 20 cadavers, which were studied with DXA and quantitative computed tomography (QCT). A mechanical strength assessment was carried out. Two new parameters were introduced: $ vBM{D}_{min}=\frac{ aBMD}{W_{PA}^{min}} $ and $ vBM{D}_{av}=\frac{ aBMD}{W_{PA}^{av}} $ (W _PA ^min —minimal vertebral body width in postero-anterior (PA) view, W _PA ^av — average PA vertebral body width). Volumetric BMD measured by QCT (vBMD), aBMD, BMAD, vBMD_min, and vBMD_av were correlated to ultimate load and ultimate stress (P_max) to find the best predictor of vertebrae BS.

Results

The coefficients of correlation between P_max and vBMD_min, vBMD_av, as well as BMAD, were r?=?0.626 (p?=?0.005), r?=?0.610 (p?=?0.006) and r?=?0.567 (p?=?0.012), respectively. Coefficients for vBMD and aBMD are r?=?0.648 (p?=?0.003) and r?=?0.511 (p?=?0.03), respectively.

Conclusions

Our results showed that aBMD normalized by vertebrae dimensions describes vertebrae BS better than aBMD alone. The considered indices vBMD_av, vBMD_min, and BMAD can be measured in routine PA DXA and considerably improve BS variability prediction. vBMD_min is superior compared to vBMD_av and BMAD.     

Protective effect of intermittent clamping of the portal triad in the rat liver on liver ischemia-reperfusion injury

Background

Intermittent clamping (IC) of the portal triad is an effective method of protecting the liver from ischemia-reperfusion injury (IR). In clinical practice, this method is employed during a resection, but its mechanism is still not clear.

Objectives

To evaluate the effect of IC on rat liver and determine its mechanisms.

Materials and Methods

Wistar rats were submitted to 60-min IC (cycles of 12-min clamping followed by 4-min reperfusion), and the samples were collected after 1, 6, and 72 hrs of reperfusion. We determined the serum activity of alanine aminotransferase (ALT), and measured the concentration of TNF-α, malondialdehyde (MDA) and myeloperoxidase (MPO) in liver homogenates. The apoptosis of hepatocytes was evaluated immunohistochemically.

Results

When compared to the IR rats, the activity of ALT decreased in the IC group in all periods of observation (the highest decrease of ~48% after 1 hr of reperfusion). When compared to the IR group, a statistically significant decrease (p < 0.05) in the TNF-α concentration (~33%) in the IC rats occurred only after 1 hr of reperfusion, and it was accompanied by a decrease in the MPO concentration after 1 and 6 hrs of reperfusion. IC reduces the effects of reactive oxygen species (ROS) activity, which has been confirmed by a statistically significant decrease in MDA concentration by 25%-35% in all studied periods. The limitation of hepatocytes apoptosis due to IC occurs in the early (~26%; p < 0.05) and late (~45%; p < 0.01) phases of reperfusion.

Conclusions

The use of IC in early phase of reperfusion brings about a decrease in TNF-α release, which can be related to liver injury due to neutrophil infiltration and apoptotic cell reduction. It seems that the reduction of lipid peroxidation may also limit the liver injury.     

Distant 10 years results of laparoscopic operative treatment in patients with varicocele

Varicocele has been regarded a curable cause of infertility for dozens of years. The impact of varicocele treatment in terms of increase in pregnancy rates is a debated issue. We evaluate data from a 10-year cohort of results from laparoscopic operative treatment of varicocele patients according to pregnancy rate, complication rate, and satisfaction with varicocele repair. Ninety seven patients were treated by means of laparoscopy between 1993 and 1996. Ten years after operation questionnaires were sent to all patients. Answers were obtained from 49/97 pts. (50,5%). Details connected with marital status, pregnancy rate, addictions and scrotal pain discomfort were collected. Statistical analysis was performed using chi-square independence test and Spearman’s rank correlation coefficient. After 10 years, 75.5% who answered the questionnaire were fully satisfied with the results of treatment, 12.3% pts of patients were partially satisfied; 63.3% of patients fathered 1 to 3 children. Married patients and those who fathered children were found to be the most satisfied with the operation. We also found the statistically significant negative dependency between smoking addiction and number of children. There were no major complications intra- or postoperatively. No harmful consequences of testicular artery ligation were found. In conclusion, long-time 10 years follow-up enables better estimation of the results of laparoscopic treatment in patients with varicocele. Pregnancy rate may depend not only on varicocele repair but on smoking addiction as well. There is still no evidence of harmful consequences due to testicular artery ligation after varicocele repair     

Direct use of the comet assay to study cell cycle distribution and its application to study cell cycle-dependent DNA damage formation

The comet assay or single cell gel electrophoresis has proven to be a versatile and sensitive method of measuring the induction and repair of DNA damage in individual cells. However, one of the drawbacks of the assay is the bias caused by changes in the ability of cells to repair DNA damage in different cell cycle phases. Whereas the bias seems less important when G0 peripheral blood lymphocytes are studied, it might cause problems when proliferating cells are investigated. In this paper, we validate the assumption that the total comet fluorescence intensity corresponds to the position of the cell in the cell cycle and can be used to assign single cells to specific cell cycle phases. To validate the approach, we used a very homogenous blood mononuclear CD34(+) cell population in G0 phase (unstimulated) or stimulated to enter the cell cycle. An analysis of the cell cycle distribution revealed that the 15 comet intensity classes and the 100 comets usually analyzed in a typical comet experiment are sufficient to obtain a reliable cell cycle distribution comparable with the results obtained by the flow cytometry for the same cell population. The effect of the cell cycle position on the results obtained by the comet assay for proliferating and non-proliferating cell populations irradiated with 3 Gy of X-radiation is also discussed.