Prediction of prostate cancer risk: the role of prostate volume and digital rectal examination in the ERSPC risk calculators

Background

The European Randomized Study of Screening for Prostate Cancer (ERSPC) risk calculators (RCs) are validated tools for prostate cancer (PCa) risk assessment and include prostate volume (PV) data from transrectal ultrasound (TRUS).

Objective

Develop and validate an RC based on digital rectal examination (DRE) that circumvents the need for TRUS but still includes information on PV.

Design, setting, and participants

For development of the DRE-based RC, we studied the original ERSPC Rotterdam RC population including 3624 men (885 PCa cases) and 2896 men (547 PCa cases) detected at first and repeat screening 4 yr later, respectively. A validation cohort consisted of 322 men, screened in 2010-2011 as participants in ERSPC Rotterdam.

Measurements

Data on TRUS-assessed PV in the development cohorts were re-coded into three categories (25, 40, and 60 cm³) to assess the loss of information by categorization of volume information. New RCs including PSA, DRE, and PV categories (DRE-based RC) were developed for men with and without a previous negative biopsy to predict overall and clinically significant PCa (high-grade [HG] PCa) defined as T stage >T2b and/or Gleason score ≥7. Predictive accuracy was quantified by the area under the receiver operating curve. We compared performance with the Prostate Cancer Prevention Trial (PCPT) RC in the validation study.

Results and limitations

Areas under the curve (AUC) of prostate-specific antigen (PSA) alone, PSA and DRE, the DRE-based RC, and the original ERSPC RC to predict PCa at initial biopsy were 0.69, 0.73, 0.77, and 0.79, respectively. The corresponding AUCs for predicting HG PCa were higher (0.74, 0.82, 0.85, and 0.86). Similar results were seen in men previously biopsied and in the validation cohort. The DRE-based RC outperformed the PCPT RC (AUC 0.69 vs 0.59; p = 0.0001) and a model based on PSA and DRE only (AUC 0.69 vs 0.63; p = 0.0075) in the relatively small validation cohort. Further validation is required.

Conclusions

An RC should contain volume estimates based either on TRUS or DRE. Replacing TRUS measurements by DRE estimates may enhance implementation in the daily practice of urologists and general practitioners.     

Importance of Manually Entering Blood Glucose Readings When Wireless-Compatible Meters Are Not Being Used with an Insulin Pump

Background:

The objective was to determine if there were differences in blood glucose monitoring (BGM) data downloaded from insulin pumps of patients who use meters that wirelessly transmit data to their insulin pumps (i.e., wireless group) and those who do not (i.e., nonwireless group).

Methods:

Blood glucose monitoring data were downloaded from the meters and insulin pumps of 47 children and adolescents with type 1 diabetes mellitus. Independent and paired t tests compared BGM data downloaded from meters and BGM data downloaded from insulin pumps.

Results:

There were significant differences in BGM data downloaded from the insulin pumps of patients using wireless meters compared to those using nonwireless meters. Wireless patients appeared to engage in more BGM, had more low and in-range BG readings and fewer very high BG readingss than nonwireless patients. However, a comparison of BGM data downloaded from meters and insulin pumps of nonwireless patients indicated that their insulin pump data significantly underestimated the number of BGM readings conducted, as well as the number of low and in-range readings, while overestimating the number of very high BGM readings.

Conclusions:

Because patients who use nonwireless-compatible meters do not manually enter their low and in-range BGM readings into the insulin pump, BGM data downloaded only from pumps may provide an incomplete representation of BGM frequency or results. It is recommended that patients use meters that directly communicate with pumps or perform bolus calculations. Patients should be educated about the importance of manually entering all BGM readings if they do not use a wireless-compatible meter with their insulin pump.     

静脉留置针新封管手法研究

[目的]为了提高静脉留置针的再通率，降低血栓性静脉炎的发生率。[方法]将入选的174例病人随机分成两组。实验组87例，对照组87例，实验组按照新方法进行封管，即一边旋转缓慢推注，一边拔出输液针封管，而对照组采用传统手法，即一边推针头一边推肝素液。[结果]实验组再通成功率为97．70％，对照组为88，50％。[结论]通过改进封管手法，可以提高再通率，同时降低血栓性静脉炎的发生率。     

Susceptibility changes following bolus injections

The general mechanism of bulk magnetic susceptibility (BMS) induced MRI contrast following a bolus injection is elaborated. Combining radiolabeled tracer data for the first pass of a bolus injection through the human brain with the application of Wiedemann's law allows us to calculate the lower limit for the time course of the vascular BMS following the injection of any contrast agent. Superparamagnetic Iron oxide particles produce a much larger effect than any mononuclear Ln(III) che-late. We also calculate the BMS changes occurring after a dilution bolus injection (of isosmolal physiological saline) subsequent to a prior slow infusion of an intravascular contrast agent. This technique bears some resemblance to the increasingly important approach that exploits changes in only the level of blood oxygenation. The calculation indicates that contrast changes after the dilution bolus injection are smaller than those following Ln(III) agent injections but larger than those due to changes in blood oxygenation and suggests a way to possibly enhance the latter. We present an In vivo study demonstrating the dilution bolus injection technique in the mouse brain, and that features its rapid repeatability. Extrapolation of these results to the human, however, indicates that the saline volumes required for venous injections, except possibly for cardiac studies, would be prohibitively large. Smaller, catheter-delivered arterial bolus injections are feasible. We also suggest a method for using an agent bolus injection to measure the parenchymal BMS, and thus the iron content, of pathologically iron-loaded tissue.     

凯时不同给药方法治疗糖尿病并发症的效果比较

[目的]比较凯时治疗糖尿病血管和神经病变时两种不同给药方法效果。[方法]A组:凯时10μg+生理盐水100mL静脉输注,持续10d;B组:凯时10μg+生理盐水20mL+弥可保500μg直接静脉推注,持续10d。[结果]A组病人静脉穿刺点随着血管走向皮肤有红、肿、痛;而B组病人皮肤局部反应明显少于A组。[结论]B组给药方法值得在临床上推广。     

Loss of acute nicotine tolerance and severity of cigarette withdrawal

A new version of the Rapid Visual Information Processing (RVIP) task has been developed in this laboratory to examine the effects of each puff from a cigarette upon continuous performance. Two cigarettes were tested and compared with a not-smoking and a sham-smoking control. The results show improvements resulting from just two puffs both in terms of correct detections and reaction times. Both measures of performance were maintained at a higher level during and after smoking, compared with not-smoking and sham-smoking.     

Fourier analysis of biological signals with a programmable calculator

A Fourier analysis program written for the Texas Instruments TI-59 programmable calculator is presented. The program determines the Fourier coefficients of any time varying periodic signal.     

Computer programs to obtain HPLC parameters of β-lactam antibiotics

Listings of BASIC and TI-59 programs are included to obtain the HPLC retention factors for β-lactam antibiotics at given antibiotic pK's, pH, and capacity factor values, which are useful in considering the different chromatographic behaviour of antibiotics as the pH varies     

Modulation of esophageal peristalsis by alterations of body position

Previous studies have demonstrated that nonviscous liquids traverse the esophagus more rapidly with the subject in the upright rather than the supine position. Conversely, similar studies have shown that viscous liquids traverse the esophagus at similar rates for both upright and supine positions. Our purpose was to define the motor correlates of these differing responses. Six normal volunteers were studied with an infused catheter system incorpoating a Dent sleeve for monitoring lower esophageal sphincter pressure. The subjects were given a series of swallows of a water and a viscous (52 centipoise) bolus in both the supine and upright positions. In the upright position, the water bolus caused an increased velocity of propagation in the proximal esophageal segment that was associated with a shortening of lower esophageal sphincter relaxation time and reductions in amplitude and duration of contraction. No significant changes in the peristaltic wave were noted with the viscous bolus during alterations of body position. We conclude that the more rapid transit of a nonviscous water bolus through the esophagus in the upright position is reflected in specific alterations of esophageal peristaltic parameters. The possible mechanisms for these differing responses are discussed.     

A computational technique for prediction of the number of microscopically visible phagosomes from data on uptake of radiolabeled outer segment material.

A program for a programmable calculator is described which can predict the number of microscopically visible phagosomes at various times given data on the rate of uptake of radiolabeled outer segment material at these times. The phagosomes are assumed to be digested such that the number of visible phagosomes decays exponentially. The half-life of this decay can be varied in the calculations, and the results can be compared with actual phagosome counts.