Comparing negative health indicators in male and female veterans with the Canadian general population

Introduction

Sex-based information on differences between Canadian veterans and the general population is important to understand veterans’ unique health needs and identify areas requiring further research. This study compared various health indicators in male and female veterans with their Canadian counterparts.

Methods

Health indicators for recent-era Regular Force veterans (released between 1998 and 2015) were obtained from the 2016 Life After Service Survey and compared with the general population in the 2015–16 Canadian Community Health Survey using a cross-sectional approach. Age-adjusted rates and 95% CIs were calculated for males and females separately.

Results

Compared with Canadians, veterans (both sexes) reported higher prevalence of fair or poor health and mental health, needing help with one or more activity of daily living, lifetime suicidal ideation and being diagnosed with mood and anxiety disorders, post-traumatic stress disorder, migraines, back problems, chronic pain, arthritis, ever having cancer, hearing problems, chronic pain and gastrointestinal problems. A higher prevalence of cardiovascular disease (all types) and high blood pressure was observed in male veterans compared with their Canadian counterparts. Within veterans only, males reported a higher prevalence of diagnosed hearing problems and cardiovascular disease compared with females; conversely females reported a higher prevalence of diagnosed migraines, mood, anxiety and gastrointestinal disorders, and needing help with activities of daily living. These sex differences are similar to the Canadian general population. Some similarities in reporting prevalence between male and female veterans (eg, fair or poor mental health, lifetime suicidal ideation, arthritis, asthma, lifetime cancer incidence, chronic pain and diabetes) were not observed in other Canadians.

Conclusion

Male and female veterans differed from comparable Canadians, and from each other, in various areas of health. Further research is needed to explore these findings, and veteran-based policies and services should consider sex differences.

Signal processing methods for reducing artifacts in microelectrode brain recordings caused by functional electrical stimulation

OBJECTIVE

Functional electrical stimulation (FES) is a promising technology for restoring movement to paralyzed limbs. Intracortical brain-computer interfaces (iBCIs) have enabled intuitive control over virtual and robotic movements, and more recently over upper extremity FES neuroprostheses. However, electrical stimulation of muscles creates artifacts in intracortical microelectrode recordings that could degrade iBCI performance. Here, we investigate methods for reducing the cortically recorded artifacts that result from peripheral electrical stimulation.

APPROACH

One participant in the BrainGate2 pilot clinical trial had two intracortical microelectrode arrays placed in the motor cortex, and thirty-six stimulating intramuscular electrodes placed in the muscles of the contralateral limb. We characterized intracortically recorded electrical artifacts during both intramuscular and surface stimulation. We compared the performance of three artifact reduction methods: blanking, common average reference (CAR) and linear regression reference (LRR), which creates channel-specific reference signals, composed of weighted sums of other channels.

MAIN RESULTS

Electrical artifacts resulting from surface stimulation were 175  ×  larger than baseline neural recordings (which were 110 µV peak-to-peak), while intramuscular stimulation artifacts were only 4  ×  larger. The artifact waveforms were highly consistent across electrodes within each array. Application of LRR reduced artifact magnitudes to less than 10 µV and largely preserved the original neural feature values used for decoding. Unmitigated stimulation artifacts decreased iBCI decoding performance, but performance was almost completely recovered using LRR, which outperformed CAR and blanking and extracted useful neural information during stimulation artifact periods.

SIGNIFICANCE

The LRR method was effective at reducing electrical artifacts resulting from both intramuscular and surface FES, and almost completely restored iBCI decoding performance (>90% recovery for surface stimulation and full recovery for intramuscular stimulation). The results demonstrate that FES-induced artifacts can be easily mitigated in FES  +  iBCI systems by using LRR for artifact reduction, and suggest that the LRR method may also be useful in other noise reduction applications.

Closed-loop cortical control of virtual reach and posture using Cartesian and joint velocity commands

OBJECTIVE

Brain-computer interfaces (BCIs) are a promising technology for the restoration of function to people with paralysis, especially for controlling coordinated reaching. Typical BCI studies decode Cartesian endpoint velocities as commands, but human arm movements might be better controlled in a joint-based coordinate frame, which may match underlying movement encoding in the motor cortex. A better understanding of BCI controlled reaching by people with paralysis may lead to performance improvements in brain-controlled assistive devices.

APPROACH

Two intracortical BCI participants in the BrainGate2 pilot clinical trial performed a visual 3D endpoint virtual reality reaching task using two decoders: Cartesian and joint velocity. Task performance metrics (i.e. success rate and path efficiency) and single feature and population tuning were compared across the two decoder conditions. The participants also demonstrated the first BCI control of a fourth dimension of reaching, the arm's swivel angle, in a 4D posture matching task.

MAIN RESULTS

Both users achieved significantly higher success rates using Cartesian velocity control, and joint controlled trajectories were more variable and significantly more curved. Neural tuning analyses showed that most single feature activity was best described by a Cartesian kinematic encoding model, and population analyses revealed only slight differences in aggregate activity between the decoder conditions. Simulations of a BCI user reproduced trajectory features seen during closed-loop joint control when assuming only Cartesian-tuned features passed through a joint decoder. With minimal training, both participants controlled the virtual arm's swivel angle to complete a 4D posture matching task, and achieved significantly higher success using a Cartesian  +  swivel velocity decoder compared to a joint velocity decoder.

SIGNIFICANCE

These results suggest that Cartesian velocity command interfaces may provide better BCI control of arm movements than other kinematic variables, even in 4D posture tasks with swivel angle targets.

Clinical Characteristics and Outcomes of Late Relapse in Stage I Testicular Seminoma

AIMS

To identify the characteristics and outcomes associated with late relapse in stage I seminoma.

MATERIALS AND METHODS

A retrospective review was carried out of all patients with stage I seminoma managed at our institution between 1981 and 2011. Data were obtained from a prospectively maintained database. Late relapse was defined as tumour recurrence > 2 years after orchiectomy.

RESULTS

Overall, 1060 stage I seminoma patients were managed with active surveillance (n=766) or adjuvant radiotherapy (n=294). At a median follow-up of 10.6 years (range 1.2-30), 142 patients relapsed at a median (range) of 14 (3-129) months; 128 on active surveillance and 14 after adjuvant radiotherapy. The late relapse rate for the active surveillance and adjuvant radiotherapy groups was 4% and 1%, respectively. There was no specific clinicopathological factor associated with late relapse. Isolated para-aortic node(s) was the most common relapse site in active surveillance patients either in late (88%) or early relapse (82%). Among the active surveillance group, no patients with late relapse subsequently developed a second relapse after either salvage radiotherapy (n=25) or chemotherapy (n=6), whereas in early relapse patients a second relapse was reported in seven (10%) of 72 patients treated with salvage radiotherapy and one (4%) of 23 patients who received chemotherapy; all second relapses were subsequently salvaged with chemotherapy. No patient in the adjuvant radiotherapy group developed a second relapse after salvage chemotherapy (n=10) or inguinal radiotherapy/surgery (n=4). Of seven deaths, only one was related to seminoma. Among active surveillance patients, the 10 year overall survival for late and early relapse groups were 100% and 96% (P = 0.2), whereas the 10 year cancer-specific survival rates were 100% and 99% (P = 0.3), respectively.

CONCLUSIONS

In stage I seminoma, the extent and pattern of late relapse is similar to that for early relapse. For active surveillance patients, selective use of salvage radiotherapy/chemotherapy for relapse results in excellent outcomes regardless of the timing of relapse, whereas salvage radiotherapy for late relapse seems to be associated with a minimal risk of second relapse.

Developmental guidelines for good chairside teaching – a consensus report from two conferences

Developmental Guidelines for Chairside Teaching are a direct outcome of 10 years of research, originally prompted by feedback from undergraduate dental students who not only thought that the teaching they received was uneven and variable in quality, but also felt strongly that they learned more with educationally trained teachers than those with little or no teacher training. Workshops embracing the views of teaching colleagues from many other Dental Schools produced a consensus view that developmental guidelines for teachers would provide a valuable resource. A conference to consider all aspects on chairside teaching and learning was convened with delegates invited from all UK Dental Schools. This was subsequently followed by a second conference to develop specific guidelines for chairside teaching and learning. The Nominal Group Technique was used in the first chairside teaching conference, and Structured Small Expert Groups were used in the second. The overall consensus from these workshops and conferences were as follows: (i) developmental guidelines for chairside teaching can act as a useful resource for teachers to improve and maintain their standard of chairside teaching, (ii) developmental guidelines can be divided into themes of organisational issues and learner and teacher qualities, and (iii) Guidelines should be 'developmental' because they encourage chairside teachers to focus on the next immediate goal to maintain and improve quality and standards. These developmental guidelines could provide a universal toolkit for improved chairside teaching which would result in a better student learning experience. Set out in this way these guidelines have currency across academic and practical skills levels, different educational systems, philosophies and country boundaries.

A comparison of two forms of teaching instruction: video vs. live lecture for education in clinical periodontology

INTRODUCTION

This crossover controlled study aimed to compare the knowledge and skill attained by third-year dental students in three clinical exercises in the discipline of periodontology through video and live lecture instruction.

METHODS

Students (n = 35) segregated into two group either viewed a video or attended a live lecture repeated over three clinical teaching sessions. Pre-test and post-test written assessments were completed and comparisons between video and live lecture done (analysis of variance, P < 0.05). Students were assessed on clinic by a simple checklist. A questionnaire was administered after all three sessions to determine preferences and opinions on video and live lecture.

RESULTS

For the combined three sessions, both video (n = 48) and live lecture (n = 47) groups attained similar mean pre-test scores. The mean post-test score was statistically significantly greater (P = 0.049) for the live lecture (74.9%, SD 14.9) compared to the video group (68.6%, SD 16.3). All students attained clinical proficiency via the simple checklist. In adding to their clinical skill, more students favoured video (97%) vs. live lecture (78.8%). Most students (97%) favoured a future combination of video and lecture.

DISCUSSION

While students were deemed clinically competent via a simple checklist, the live lecture group performed better than the video group via the in-depth post-test assessment. Students had a preference for video and would like it integrated in the lecture rather than act as a substitute for the lecture.

CONCLUSION

The use of video alone in clinical periodontology training may have limitations unless supplemented by appropriate learning activities.

Modelling and fabrication of GaAs photonic-crystal cavities for cavity quantum electrodynamics

In this paper, we present recent progress in the growth, modelling, fabrication and characterization of gallium arsenide (GaAs) two-dimensional (2D) photonic-crystal slab cavities with embedded indium arsenide (InAs) quantum dots (QDs) that are designed for cavity quantum electrodynamics (cQED) experiments. Photonic-crystal modelling and device fabrication are discussed, followed by a detailed discussion of different failure modes that lead to photon loss. It is found that, along with errors introduced during fabrication, other significant factors such as the presence of a bottom substrate and cavity axis orientation with respect to the crystal axis, can influence the cavity quality factor (Q). A useful diagnostic tool in the form of contour finite-difference time domain (FDTD) is employed to analyse device performance.

One dimensional resonant Fibonacci quasicrystals: noncanonical linear and canonical nonlinear effects

A detailed experimental and theoretical study of the linear and nonlinear optical properties of different Fibonacci-spaced multiple-quantum-well structures is presented. Systematic numerical studies are performed for different average spacing and geometrical arrangement of the quantum wells. Measurements of the linear and nonlinear (carrier density dependent) reflectivity are shown to be in good agreement with the computational results. As the pump pulse energy increases, the excitation-induced dephasing broadens the exciton resonances resulting in a disappearance of sharp features and reduction in peak reflectivity.

Stakeholder perceptions of chairside teaching and learning in one UK dental school

As a hands-on clinical educational programme, undergraduate dentistry is an anomaly in higher education. This study aimed to evaluate the perceptions of chairside teaching of dental team stakeholders, including dental nurses, dental students and dental tutors at a single UK dental school. From this sample the penetration of current learning and teaching innovations within higher education into the specialist field of clinical dentistry could be evaluated. This article is the first of a series of four which investigates the perceptions of stakeholders of chairside teaching at a single dental school. The second evaluates chairside teaching on a UK wide scale. The third provides educational tools to encourage collaboration and sharing good chairside teaching practice. A further accompanying article reviews some of the educational methodology and innovations in teaching and learning that may be applied to dentistry.

Attempts to grow optically coupled Fibonacci-spaced InGaAs/GaAs quantum wells result in surface gratings

An instability in the growth of nonperiodic InGaAs/GaAs multiple quantum well samples, ordinarily of high-quality when grown with equal periods of order of half the wavelength of light in the material, leads to a dramatic microscopic, self-organized surface grating. This effect was discovered while growing quantum wells with two unequal barrier lengths arranged in a Fibonacci sequence to form an optical quasicrystal. A laser beam incident normal to the surface of the sample is diffracted into a propeller-shaped pattern. The sample surface has a distinctly cloudy appearance when viewed along one crystal axis but is mirror-like when the sample is rotated 90 degrees. The instability results in a five-fold increase in the absorption linewidth of the heavy-hole exciton transition. Atomic force microscopy, transmission electron microscopy, and scanning electron microscopy were used to study the samples.

Excitonic polaritons in Fibonacci quasicrystals

The fabrication and characterization of light-emitting one-dimensional photonic quasicrystals based on excitonic resonances is reported. The structures consist of high-quality GaAs/AlGaAs quantum wells grown by molecular-beam epitaxy with wavelength-scale spacings satisfying a Fibonacci sequence. The polaritonic (resonant light-matter coupling) effects and light emission originate from the quantum well excitonic resonances. Measured reflectivity spectra as a function of detuning between emission and Bragg wavelength are in good agreement with excitonic polariton theory. Photoluminescence experiments show that active photonic quasicrystals, unlike photonic crystals, can be good light emitters: While their long-range order results in a stopband similar to that of photonic crystals, the lack of periodicity results in strong emission.

Detection of novel variant TMPRSS2 /ERG fusion transcripts suggests independent genomic alterations may underlie origin of multi-centric prostate cancer

10029

Background: Most of the early successes in identifying chromosomal translocations in neoplasias came from the study of hematological malignancies and sarcomas, with limited evidence that consistent genomic rearrangements were present in epithelial malignancies. Recently it was reported that ∼75% of prostate cancers carry a genomic rearrangement leading to fusion of the TMPRSS2 locus to either the ERG or ETV1 genes (both ETS transcription factors). In the fusion gene, the androgen-sensitive promoter elements of TMPRSS2 are thought to mediate over-expression of these ETS transcription factors. Over-activity of the ETS family of transcription factors has been suggested to be involved in the transition from pre-neoplasia to carcinoma as they regulate genes involved in processes such as adhesion, motility, invasion and angiogenesis. Methods: Using both RT-PCR and FISH with published primers and BACs respectively we analyzed 15 samples of prostatic carcinoma from radical prostatectomies and sequenced a subset of the TMPRSS2/ERG fusions. Results: We have found ERG-TMPRSS2 fusion transcripts in 6 samples and no ETV1-TMPRSS2 fusions. Of the 6 fusion tumours, 5 were Gleason 7 and 1 was Gleason 9. Tumour stages ranged from T2a-T3b. One sample with multi-centric carcinoma exhibited 2 distinct in-frame rearrangements generating novel TMPRSS2 /ERG fusion transcripts. Variant I TMPRSS2/ERG transcript was 430 bp and it led to fusion of exons 1 and 2 of the TMPRSS2 gene with exons 5 and 6 of the ERG gene. Variant II TMPRSS2/ERG fusion transcript was slightly smaller at 350 bp and it led to fusion of exon 1 of the TMPRSS2 gene to exons 5 and 6 of the ERG gene. These novel transcripts appear to be smaller than the published fusion proteins but preliminary analysis suggests that all known regulatory and functional protein domains are maintained. Conclusions: The demonstration of two new TMPRSS2/ERG variant fusion transcripts in prostate cancer deserves further study to evaluate their functional impact and prognostic and pathological importance. Moreover the presence of two distinct transcripts within a single multi-centric tumor provides genomic evidence that independent clonal neoplasms can arise synchronously in prostate cancer.

No significant financial relationships to disclose.

Entanglement between a photon and a quantum well

The lack of translational invariance perpendicular to the plane of a single quantum well causes equal probability for spontaneous emission to the left or right. Combining one emission path from the left and one from the right into a common detector leads to interference fringes for fundamentally indistinguishable paths corresponding to geometries where the same in-plane momentum is transferred to the quantum well. For all other paths, no interference is observed because of the entanglement between the photon and extended Bloch states of the many-body system. In multiple-quantum-well structures the interference can be controlled via the spacing between the wells.

A unique renal lesion in common variable immunodeficiency

This article reports the case of a 33-year-old woman with common variable immunodeficiency (CVI) who developed renal failure 17 years after diagnosis and initiation of treatment with monthly IVIG. A renal biopsy revealed mesangial and paramesangial immune complex deposition and interstitial granulomatous infiltration. Renal function improved with oral corticosteroids, but did not return to normal. Decreasing the dose of IVIG had no effect on renal function. Immune dysfunction can be associated with both granulomatous disease and immune complex glomerulonephritis, or the latter may be related to chronic infection or immunoglobulin use. This is the first report of concomitant glomerular-tubulointerstitial lesions in this immunodeficiency syndrome. Renal function should be closely followed in patients with CVI.

Development of a radiofrequency based thermal therapy technique in an in vivo porcine model for the treatment of small renal masses

PURPOSE

Incidentally detected small renal tumors appear to grow slowly and be localized to the kidney. Minimally invasive therapies are being investigated as alternatives to standard surgical techniques. Radiofrequency ablation has been reported for the treatment of small renal cell carcinomas. We developed a radiofrequency technique and established its efficacy and safety in a large animal model.

METHODS AND METHODS

A total of 22 lesions were created in normal kidneys of 7 pigs. Radiofrequency energy was administered during open exposure of the kidneys or percutaneously under ultrasound guidance. Lesion development was monitored with gray-scale and power Doppler ultrasound. To avoid heating surrounding tissues new hydro-dissection and gas-dissection techniques were developed. Lesion sizes and characteristics were assessed by ultrasound and pathological examination.

RESULTS

No complications were observed due to probe insertion and removal. Perirenal structures were thermally damaged before the development and application of the dissection techniques. Lesion size was accurately predicted by gray-scale ultrasound on day 7. Loss of perfusion in the ablated volume was confirmed by power Doppler ultrasound. Lesions were wedge-shaped, presumably due to the effects of heating on segmental blood flow distribution. Pathological examination revealed changes consistent with thermal injury and ischemic type infarction.

CONCLUSIONS

Radiofrequency thermal therapy is an effective and efficient method for ablating normal renal tissue in the pig. It may be applied percutaneously under ultrasound guidance with minimal complications provided that vital adjacent structures are protected from thermal damage. Further studies are required in humans before adopting this technique as definitive treatment for small renal cell carcinoma.

V89L polymorphism of type-2, 5-alpha reductase enzyme gene predicts prostate cancer presence and progression

OBJECTIVES

The valine (V) to leucine (L) polymorphism of the SRD5A2 gene is associated with 5-alpha reductase-2 activity; patients with the V allele have high activity and patients with the L allele have low activity. We examined whether this polymorphism predicts the presence of prostate cancer in 320 men without cancer who underwent biopsy and cancer progression in 318 men who underwent radical prostatectomy.

METHODS

The effect of the SRD5A2 gene in predicting the presence of prostate cancer was examined using logistic regression analysis, controlling for established risk factors. The effect of the SRD5A2 gene in predicting prostate cancer progression was examined using a nested, matched, case-control design. Most of the participants were white.

RESULTS

Of the 320 men, 158 (49.4%) were found on biopsy to have prostate cancer. The overall distribution of the V/V, V/L, and L/L genotypes was 47.5%, 42.5%, and 10.0%, respectively. The adjusted odds ratio for having prostate cancer for patients with at least one V allele was 2.53 compared with patients with the L/L genotype (P = 0.03). Of the 318 patients with cancer, 80 had biochemically detected recurrence and 238 had no evidence of recurrence. The odds ratio for progression for patients with at least one V allele was 3.32 (95% confidence interval 1.67 to 6.62, P = 0.0006) compared with patients with the L/L genotype.

CONCLUSIONS

Men who have the V allele of the SRD5A2 gene have a twofold increase in the risk of prostate cancer development and an additional twofold increase in the risk of progression compared with men with the L/L genotype.

Significance of the CAG repeat polymorphism of the androgen receptor gene in prostate cancer progression

PURPOSE

The CAG repeat polymorphism of the androgen receptor gene has been associated with an increased prostate cancer risk, and the repeat length correlated with cancer stage and grade at presentation. Men with an allele length of </= 18 CAG repeats have a 2-fold increase in risk for high-stage or high-grade prostate cancer, compared with patients with a longer CAG repeat. We examined the significance of the CAG repeat polymorphism of the androgen receptor gene for predicting prostate cancer progression among 318 patients treated by radical prostatectomy for clinically localized prostate cancer between 1987 and 1994.

MATERIALS AND METHODS

Leukocyte DNA was collected and genotyping of the CAG repeat polymorphism was performed using a PCR-based direct sequencing method. Risk ratios were calculated for developing biochemical recurrence for patients associated with an allele length of </= 18 CAG repeats, compared with patients with an allele length of >18 CAG repeats, controlling for grade, stage and serum PSA level at diagnosis using Cox proportional hazard modeling.

RESULTS

Overall, the CAG repeat allele was not predictive of recurrence; tumor grade, stage and PSA level at diagnosis were the only predictors of recurrence in a multivariate analysis. However, for patients at low risk for recurrence (Gleason score 2 to 6, stage pT2, and PSA </= 10 ng./ml.), the relative risk of recurrence associated with an allele of </= 18 CAG repeats was 8.07 (95% C.I., 2.02 to 32.2, p = 0.004), compared with patients with an allele length of >18 CAG repeats. In contrast, for patients at high risk of recurrence (Gleason score >/= 7, stage pT3/4, or PSA >10 ng./ml.), the relative risk associated with the </= 18 CAG repeat allele was 0.72 (95% C.I., 0.33 to 1.57, p = 0.41), compared with patients with the >18 CAG repeat allele.

CONCLUSIONS

The length of the CAG repeat polymorphism of the androgen receptor gene may be important for prostate cancer recurrence among patients who are otherwise at low risk for recurrence after radical prostatectomy. These findings have potential implications for patient selection for adjuvant treatment, and for the development of novel treatments.

Standard off-cord lung oblique fields do not include the entire mediastinum: a computed tomography simulator study

The routinely recommended target volume for off-cord lung oblique fields in the treatment of postoperative bronchogenic carcinoma includes the entire mediastinum, as defined by coverage of the contralateral mainstem bronchus and subcarinal space. However, this may be difficult to accomplish with the field angles of 20 degrees to 40 degrees, recommended in the recently completed Intergroup Trial (Radiation Therapy Oncology Group 91-05). This project was undertaken to define the oblique angle necessary to encompass the entire mediastinum as determined by computerized tomography simulator verification. Axial computerized tomography simulation images of 25 patients with non-small-cell lung cancer were used in this study. Ten patients had prior lobectomy or pneumonectomy as part of their management. The contralateral mainstem bronchus, subcarinal space (SS), and the spinal cord were each contoured as separate volumes. The length of the contralateral mainstem bronchus was defined as extending from the carina to the bifurcation of the lobar bronchi. The subcarinal space was defined as a triangular space (in a coronal plane) with the carina at the apex, the mainstem bronchi superiorly, and a horizontal line 5 cm below the carina as the base of the triangle. The minimal angle to encompass the contralateral mainstem bronchus and subcarinal space, and to exclude the spinal cord was determined for each patient. The contoured volumes did not have additional margin added. The position of the carina was scored as "midline" if located in the midsagittal plane, or "off-midline" if deviated to either side from midline. Midline deviation was determined at the level of the carina to evaluate possible anatomical distortion relating to the tumor or prior surgery, and its effect on the minimal angle was assessed. The median minimal angle measured was 45 degrees (range: 28-65 degrees) for the entire group, and in 64% of those evaluated, this oblique angle was significantly greater than the 40 degrees recommended in Radiation Therapy Oncology Group guidelines (p = 0.017). In patients without midline deviation (n = 17), the median minimal angle was 45 degrees (range: 28-60 degrees), and in patients with midline deviation (n = 8), it was determined to be 44 degrees (range: 27-65 degrees), with no statistical difference noted between the two groups (p = NS). Although midline deviation was present in 4 of 10 patients previously resected, the above relationship remained unchanged. Based on computerized tomography simulation verification, off-cord oblique field angles of 20 degrees to 40 degrees do not adequately cover the entire mediastinum in most patients. To adequately encompass the entire mediastinum as defined in the Intergroup Trial (Radiation Therapy Oncology Group 91-05) with off-cord oblique fields, treatment angles greater than 40 degrees are necessary. Whether the potential increase in lung volume exposed to radiation from these larger angles results in a poorer therapeutic ratio requires further investigation.

A comparative analysis of sextant and an extended 11-core multisite directed biopsy strategy

PURPOSE

The 3 tumor locations unsampled by conventional sextant biopsies that have been identified on composite 3-dimensional reconstruction of 180 radical prostatectomy specimens are the anterior transition zone, midline peripheral zone and inferior portions of the anterior horn in the peripheral zone. We evaluated an 11-core multisite directed biopsy scheme incorporating these alternate areas and conventional sextant biopsies in 362 patients from 2 institutions.

MATERIALS AND METHODS

Patients without a prior diagnosis of cancer underwent ultrasound guided 11-core biopsies which included conventional sextant and 3 alternate sites. All specimens were separated for specific location identification. Biopsy was performed in 183 patients at MD Anderson Cancer Center (group 1) and in 179 at Toronto General Hospital (group 2). All group 2 and 54% of group 1 patients (98 of 183) had a prior biopsy negative for cancer.

RESULTS

Median prostate specific antigen was higher in group 2 than in group 1 patients (11.5 versus 9.5 ng./ml., p = 0.016). Overall a 33% increase (36 of 110 patients) in cancer detection was observed when biopsy technique included the alternate areas (p = 0.0021). The anterior horn was the most frequently positive biopsy site followed by the transition zone and midline sites. The 11-core technique had significantly better cancer detection rates when digital rectal examination and transrectal ultrasound were normal, and in men with serum prostate specific antigen between 4.1 and 10 ng./ml.

CONCLUSIONS

Biopsies of the alternate sites suggested by our simulation studies are feasible and reproducible. This new strategy significantly enhanced (p = 0.0075) prostate cancer detection compared to conventional sextant biopsies in men undergoing a repeat procedure.

Radiation exposure to children during coil occlusion of the patent ductus arteriosus

The risks of excessive exposure to ionizing radiation are well described and measures are routinely taken to limit such exposure to both patient and personnel in the catheterization laboratory. Coll occlusion of the patent ductus arteriosus (PDA) as well as other more complex pediatric interventions has raised concern regarding radiation exposure, particularly as minimally invasive surgical techniques are being developed which lack such exposure risk. In eight consecutive patients, aged 0.7-7 years (median, 2.3 years), coil occlusion of a PDA was performed and surface entrance radiation dose determined by thermoluminescent dosimetry (TD). Total cumulative doses (PA + lateral dose) were also calculated for each patient. Entrance and cumulative dose was likewise measured in 12 patients undergoing standard diagnostic catheterization (DC) and in 5 consecutive patients undergoing pulmonary balloon valvuloplasty (PBV). The groups were comparable in age, weight, and body surface area (BSA). Total cumulative dose in the PDA patients was 97 +/- 25 mGy (mean +/- SE). There was no significant difference between the three groups in entrance dose absorbed at each location or in total cumulative dose. The mean total fluoroscopy time in the PDA occlusion group was significantly less than that of the PBV group (10.1 +/- 1.81 min vs. 19.3 +/- 2.29 min, P < 0.05) but was comparable to the DC group (13.2 +/- 1.5 min, P = NS). When the subjects were analyzed collectively, no correlation between fluoroscopy time and measured entrance dose was observed. The strongest correlates of total cumulative dose were patient weight (r = 0.67, P < 0.001) and BSA (r = 0.62, P = 0.001). Patients undergoing coil occlusion of a PDA are not exposed to increased radiation entrance dose compared to those undergoing standard DC and PBV. Furthermore, surface entrance radiation dose as determined by TD varies according to patient size for a given fluoroscopy time.

P300 scalp amplitude distribution as an index of deception in a simulated cognitive deficit model

Truth-telling (Truth) and simulated malingering (Malinger) groups were tested in a matching-to-sample procedure in which each sample three-digit number was followed by a series of nine test numbers, only one of which matched the sample. P300 was recorded during test-number presentation. Group analyses revealed differences between the P300s of the groups in unscaled amplitude, but not latency, in response to match and mismatch stimuli. P300 amplitudes at Fz, Cz, and Pz were scaled to remove possible confounding effects of amplitude in tests of the interactions of site with other variables. Significant interactions of both stimulus-type (match vs. mismatch) and group (Truth vs. Malinger) with site were obtained. Within the Malinger group, a significant interaction was obtained (scaled data) between site and response type (honest vs. dishonest). These interactions suggest that deceptive and honest responding are associated with different neurogenerator sets or different sets of P300-overlapping components. In within-individual analyses, 100% of the Truth participants and 87% of the Malinger participants were found to have larger P300 responses at Pz to match stimuli than to mismatch stimuli on the basis of intra-individual bootstrap tests. This represents an improvement in comparison with our related, previous report on a matching-to-sample test using only one test stimulus per sample.

A comparison of bitemark injuries between fatal wolf and domestic dog attacks

Bitemark patterns in adult human victims following a fatal wolf pack attack and a domestic dog pack attack are compared. Both victims exhibited a concentration of wounds to the extremities, left and right torso, but not to the groin or internal organs. The neck and face of the domestic dog attack victim were primary sites of attack while the feral wolf pack victim was spared damage to the neck, but had facial tissue destroyed postmortem. Most punctures were found on the ventral aspect of the domestic victim and dorsal aspect of the feral victim. It is speculated that most wounds were attributable to dominant animals of both packs and in both victims and this suggests a co-ordination of activity between. Differences in bitemark patterns may well have been caused in part by differences in genetics, training, breeding, socialization and impetus of attack between wolves and dogs. Distinct differences in bitemark patterns were found in these two human victims of a wolf and domestic dog attacks.

P300 correlates of simulated malingered amnesia in a matching-to-sample task: topographic analyses of deception versus truthtelling responses

Two experiments using a P300-enhanced Forced Choice Procedure (P3FCP) investigated simulated amnesia in a matching-to-sample task. In Experiment 1, successful manipulation of subjects towards different behavioral hit rates (75-80% vs. 85-90%) did not adversely affect the diagnostic sensitivity of match-mismatch Pz-P300 amplitude analyses, allowing detection of 69% of simulators. P300 amplitudes of simulators (Malinger group) were as large as those of truth-tellers (truth group, a control), indicating no dual task-related (Malingering) reduction across different behavioral hit rates. Experiment 2 found no main effect of oddball type, match vs. mismatch, on P300 (P3) amplitude with a mismatch-rare variant of the P3FCP. This study also revealed larger Pz-P3s in the Malingering (vs. Truth-telling) condition. Subsequent topographic analyses suggested different Truth and Malinger scaled P3 amplitude topographies in both these sets of P3FCP data and in those from a previous autobiographical memory paradigm. Further analysis yielded preliminary evidence for a common deception-related P3 amplitude topography across different paradigms/conditions.

The Internet: an essential tool for college health networking

With the advent of the Internet, college health professionals have available to them a new setting in which to network. The Internet provides opportunities for immediate communication with a large and diverse community of colleagues. Through both the Student Health Service (SHS) Discussion Group and numerous health-related databases, the Internet serves as a powerful research tool for program development and improvement. Answers to queries about practice options, solutions for local problems, and support of innovative policies can be received almost instantaneously from college health professionals from across the United States and Canada. In this article, the authors summarize the history and current use of the SHS Discussion Group, provide a brief overview of Internet basics, and identify more advanced uses of the Internet by college health professionals.

The effect of co-administration of zolpidem with fluoxetine: pharmacokinetics and pharmacodynamics

Since early treatment of depression with Selective Serotonin Reuptake Inhibitor (SSRI) can be associated with insomnia, daytime antidepressive therapy with SSRI is often combined with nighttime administration of a hypnotic. This study attempted to evaluate the pharmacokinetic and pharmacodynamic interactions between zolpidem 10 mg, a short-acting hypnotic, and fluoxetine 20 mg, an SSRI. Twenty-seven healthy male volunteers (mean age 23.5 years, range 20 - 29) received zolpidem and fluoxetine in the following open design: zolpidem on night 1, a morning dose of fluoxetine daily from day 2 through day 18 and zolpidem on night 18. Using HPLC, plasma levels of zolpidem, fluoxetine, and norfluoxetine were determined throughout night 1 for zolpidem, night 18 for zolpidem, fluoxetine, and norfluoxetine on days 16 and 17 for fluoxetine and norfluoxetine. Morning psychomotor tests were performed on days 1, 2, 18, and 19. Statistical analysis of data consisted of repeated measures of ANOVA. There was no significant difference in AUC, C(max), and T1/2 of zolpidem plasma concentrations between night 1 (zolpidem) and night 18 (zolpidem and fluoxetine). There was a significantly higher zolpidem plasma level at 0.5 hours after dosing together with a significantly shorter T(max) on night 18 compared to night 1. There was no significant difference in C(min) of plasma fluoxetine and norfluoxetine levels between day 16 and 17 of fluoxetine dosing, and there was no difference in T(max) between day 17 (fluoxetine) and day 18 (fluoxetine and zolpidem). There was a 3 - 4% increase in AUC and C(max) of fluoxetine and norfluoxetine plasma concentrations in the presence of zolpidem. There was no difference in the next morning performance tests after nighttime treatment of zolpidem alone after 17 consecutive days of fluoxetine treatment, or after zolpidem in the presence of steady-state plasma concentrations of fluoxetine. Both zolpidem and fluoxetine were well tolerated alone or in combination. It is concluded that the onset of action of zolpidem may possibly be shortened in the presence of fluoxetine, but no other significant pharmacokinetic or pharmacodynamic interactions occurred between zolpidem and fluoxetine.

Potential underdosing with the use of electron beam therapy in patients with cervical adenopathy and advanced head and neck cancer

To define the adequacy of electron beam therapy in the treatment of N1-N3 head and neck cancer, 24 patients with primary head and neck cancers and N1-N3 cervical adenopathy received primary radiation therapy with or without chemotherapy for definitive control of their disease. All patients underwent computerized tomography (CT) to assist in the design of treatment to the posterior neck with electron beams after photon therapy to the level of spinal cord tolerance. Treatment with electrons to the posterior neck in patients with N1 disease was adequate in 92% (11/12) of patients. However, in patients with N2 and N3 disease, electron beam treatment failed, because of spinal cord tolerance problems, to cover the disease adequately in 92% (11/12). It is concluded that CT should be employed routinely in patients with N1-N3 neck disease to determine the proper electron energy prescription. For some patients, electron beam may not be appropriate, making it necessary to use individual planning to treat adequately the neck disease and avoid the spinal cord.

Detecting simulated amnesia with event-related brain potentials

Two experiments were done in which groups of normal college undergraduate subjects were instructed to simulate autobiographical amnesia related to head injury. The subjects were tested for autobiographical knowledge with pencil-and-paper recall and recognition tasks, and on another day, with recognition tasks in which event-related potentials were recorded in response to the same autobiographical items, this time presented on a display screen. In the first study, three Event-Related Potential (ERP) block types were utilized: 1) a block in which the subject's birthdate was an oddball with p = 0.11 and other dates (not relevant to the subject) had p = 0.89, 2) a block in which phone numbers were used as stimuli, and 3) a block in which (mothers' maiden) names were used as stimuli. Only birthdate blocks were used in the second study. A P300 ERP was seen in response to rare, personally relevant items. In both studies, the main effect of stimulus type (personally relevant versus not personally relevant) on P300 amplitude was significant (p < 0.0001) and there was no main effect of block type in the first study. Under a sophisticated malingering instruction set, about 15% of the items were correctly recalled and about 50% were correctly recognized by simulators in pencil-and-paper tests. Under a naive malingering instruction set, most simulating subjects failed to recall and recognize autobiographical items. In the first study, an arbitrarily but a priori derived discrimination criterion based on a subject's average P300 amplitude afforded 92% correct discrimination of simulating individual subjects for birthdates and phone numbers. The value was 77% for mothers' maiden names. The same criterion applied to the single birthdate block in the second study yielded 93% correct discrimination. The results suggest the P300 may be useful in detection of malingered amnesia.

An urban outbreak of visceral leishmaniasis in Natal, Brazil

The epidemiological pattern of visceral leishmaniasis in north-eastern Brazil is changing. The disease was typically seen in rural, endemic areas, but is now occurring as an epidemic in the city of Natal where 316 cases have been reported since 1989; 49% were in children less than 5 years of age. The principle clinical and laboratory findings were weight loss, fever, hepato-splenomegaly, anaemia, leucopenia and hypergammaglobulinaemia. Elevated transaminases and hyperbilirubinaemia were also observed. The diagnosis was confirmed in 87% of cases by identifying amastigotes in aspirates from bone marrow or spleen. Five isolates were identified as Leishmania (L.) chagasi by isoenzyme analysis. The mortality rate was 9%; all deaths occurred during the first week in hospital. One person had concurrent human immunodeficiency virus infection. Among 210 household contacts and neighbours of patients from the endemic area examined for evidence of L. (L.) chagasi infection, 6 additional cases of visceral leishmaniasis were diagnosed. Thirty-eight percent of house-mates and neighbours gave a positive Montenegro skin test reaction, indicating prior subclinical infection.

Potential underdosing with the use of electron-beam therapy in patients with cervical adenopathy and advanced head and neck cancer

To define the adequacy of electron-beam therapy in the treatment of N1-N3 head and neck cancer, 24 patients with primary head and neck cancers and N1-N3 cervical adenopathy received primary radiation therapy with or without chemotherapy for definitive control of their disease. All patients underwent computerized tomography (CT) to assist in the design of treatment to the posterior neck with electron beams after photon therapy to the level of spinal cord tolerance. Treatment with electrons to the posterior neck in patients with N1 disease was adequate in 92% (11/12) of patients. However, in patients with N2/N3 disease, electron beam failed, because of spinal-cord tolerance problems, to adequately cover disease in 92% (11/12). It is concluded that CT should be routinely employed in patients with N1-N3 neck disease to determine the proper electron-energy prescription. For some patients, electron beam may not be appropriate, making it necessary to use individual planning to treat adequately the neck disease and avoid the spinal cord.

Purification and characterization of Epstein-Barr virus gp340/220 produced by a bovine papillomavirus virus expression vector system

Our initial results with a bovine papilloma virus (BPV) vector expression system indicated that we could produce significant amounts of Epstein-Barr virus (EBV) gp340/220 in the supernatant of a mouse fibroblast cell line. We have now extended these findings to show that the truncated version of gp340/220, where the membrane anchor sequence is deleted, is produced even after extended passage of the cells, at a level of approximately 1 mg/4 x 10(8) cells. A simple purification protocol using Sephacryl S300HR and gelatin agarose gives a product which is greater than 90% pure. This product is recognized by anti-gp340 monoclonal antibodies from five different epitope groups and induces antibody that recognizes the authentic gp340/220 and neutralizes EBV in vitro. The purified gp340/220 can be used in ELISA and stimulates the proliferation of T-cell clones specific for gp340/220. These characteristics, together with the fact that BPV-transformed lines have been utilized for the production of pharmaceuticals for use in humans, suggest that this gp340/220 is suitable as a source of antigen for vaccination to prevent EBV infection and related diseases.

Inflammatory mediator release on conjunctival provocation of allergic subjects with allergen

To evaluate the role of inflammatory mediators in the pathogenesis of the ocular allergic response, 23 subjects with positive histories of allergies to either cat dander or ragweed pollen and positive skin tests to the appropriate allergen extract were recruited and were subjected to conjunctival provocation. The tear duct of the left eye of each subject was blocked with a collagen plug while the right eye was left unplugged. In all cases, the eye was initially provoked with saline and subsequently with the appropriate allergen extract. Nonallergic subjects, or allergic subjects provoked with nonrelevant allergen, were used as control subjects. After each provocation, symptoms were recorded, and tears were collected with preweighed strips of filter paper (Schirmer strip). Each strip was placed into a tared tube containing fluid appropriate for the optimal preservation of the mediator to be measured. It was therefore possible to calculate the weight of tears collected and to express mediator levels per milliliter of tears. All allergic subjects demonstrated a positive symptomatic response to allergen challenge, whereas the control subjects remained asymptomatic. Blockage of the tear duct did not significantly alter the response. For allergic subjects, the levels of histamine, kinins, prostaglandin D2, albumin, and TAME-esterase activity were all significantly (p less than 0.005 in each case) greater after allergen challenge than after saline challenge. Furthermore, levels of each of these mediators after allergen challenge (expressed as increases above levels after saline provocation) were significantly greater for allergic subjects than for control subjects (p less than 0.005 in each case). Thus, the clinical response to conjunctival provocation with allergen is associated with increases in the levels of inflammatory mediators in tears.