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Hamlet’s first encounter with the Ghost serves principally, in narrative terms at least, to deliver the news, both to the play’s protagonist and its audience, that Claudius is a treasonous,...

Background Free Open-Access Medical education (FOAM) use among residents continues to rise. However, it often lacks quality assurance processes and residents receive little guidance on quality assessment. The Academic Life in Emergency Medicine Approved Instructional Resources tool (AAT) was created for FOAM appraisal by and for expert educators and has demonstrated validity in this context. It has yet to be evaluated in other populations. Objectives We assessed the AAT's usability in a diverse population of practicing emergency medicine (EM) physicians, residents, and medical students; solicited feedback; and developed a revised tool. Methods As part of the Medical Education Translational Resources: Impact and Quality (METRIQ) study, we recruited medical students, EM residents, and EM attendings to evaluate five FOAM posts with the AAT and provide quantitative and qualitative feedback via an online survey. Two independent analysts performed a qualitative thematic analysis with discrepancies resolved through discussion and negotiated consensus. This analysis informed development of an initial revised AAT, which was then further refined after pilot testing among the author group. The final tool was reassessed for reliability. Results Of 330 recruited international participants, 309 completed all ratings. The Best Evidence in Emergency Medicine (BEEM) score was the component most frequently reported as difficult to use. Several themes emerged from the qualitative analysis: for ease of use-understandable, logically structured, concise, and aligned with educational value. Limitations include deviation from questionnaire best practices, validity concerns, and challenges assessing evidence-based medicine. Themes supporting its use include evaluative utility and usability. The author group pilot tested the initial revised AAT, revealing a total score average measure intraclass correlation coefficient (ICC) of moderate reliability (ICC = 0.68, 95% confidence interval [CI] = 0 to 0.962). The final AAT's average measure ICC was 0.88 (95% CI = 0.77 to 0.95). Conclusions We developed the final revised AAT from usability feedback. The new score has significantly increased usability, but will need to be reassessed for reliability in a broad population.

Autonomous vehicles cooperate to perform many life-saving and cost-saving applications such as advanced collision warning, tailgating and traffic routing. As the use of autonomous vehicles increases, the transportation infrastructure as a whole becomes highly susceptible to cyber attacks due to the number of components that communicate with each other over wireless networks and the Internet.

Blockchains are used to perform state agreement in a distributed system. However, there is no way to validate off-chain actions, such as physical actions, in the current architecture. This paper proposes a new blockchain architecture which features locally physically-verified transactions. From this new architecture, this paper presents a protocol for securing vehicular ad-hoc networks (VANETs) without the need to constantly communicate with roadside units (RSUs) or other infrastructure components. However, issues such as privacy in VANETs and Blockchains are left to future work. This paper shows the results from simulations of the current system in order to note its weaknesses. In particular, this paper can be used as a benchmark to show that ideas such as Proof-of-Work and full blockchain validation cannot work in a purely peer-to-peer VANET.

Study objective Online educational resources such as blogs are increasingly used for education by emergency medicine clinicians. The Social Media Index was developed to quantify their relative impact. The Medical Education Translational Resources: Indicators of Quality (METRIQ) study was conducted in part to determine the association between the Social Media Index score and quality as measured by gestalt and previously derived quality instruments. Methods Ten blogs were randomly selected from a list of emergency medicine and critical care Web sites. The 2 most recent clinically oriented blog posts published on these blogs were evaluated with gestalt, the Academic Life in Emergency Medicine Approved Instructional Resources (ALiEM AIR) score, and the METRIQ-8 score. Volunteer raters (including medical students, emergency medicine residents, and emergency medicine attending physicians) were identified with a multimodal recruitment methodology. The Social Media Index was calculated in February 2016, November 2016, April 2017, and December 2017. Pearson's correlations were calculated between the Social Media Index and the average rater gestalt, ALiEM AIR score, and METRIQ-8 score. Results A total of 309 of 330 raters completed all ratings (93.6%). The Social Media Index correlated moderately to strongly with the mean rater gestalt ratings (range 0.69 to 0.76) and moderately with the mean rater ALiEM AIR score (range 0.55 to 0.61) and METRIQ-8 score (range 0.53 to 0.57) during the month of the blog post's selection and for 2 years after. Conclusion The Social Media Index's correlation with multiple quality evaluation instruments over time supports the hypothesis that it is associated with overall Web site quality. It can play a role in guiding individuals to high-quality resources that can be reviewed with critical appraisal techniques.

We evaluated hospitalized patients with a history of methicillin-resistant Staphylococcus aureus (MRSA) for persistent colonization and need for contact precautions. Up to 3 daily cultures of nares, skin, and any present wounds were compared with a single nasal polymerase chain reaction (PCR) assay. Most patients (76.2%) were no longer colonized with MRSA. A single PCR assay was sufficient to exclude persistent colonization and environmental contamination and remove the contact precautions.

To describe the incidence of difficult and failed intubations in obstetric patients during a 6 year period monitored by a quality assurance program together with American Society of Anesthesiologists Physical Status (ASA PS) scores, and obesity (body mass index30 kg/mFollowing Institutional Review Board approval, data about obstetric patients who experienced unanticipated difficult or failed intubations from 2010 to 2015 was obtained from the quality assurance database of a large, community-based anesthesiology group practice. The database employs standardized definitions for difficult intubation (3 laryngoscopic attempts by experienced providers) and failed intubation (inability to intubate leading to surgical airway or waking up the patient). ASA PS scores and comorbidities were also identified for obstetric general anesthetics using an internally developed quality assurance program, Quantum Clinical Navigation System.There were 2802 obstetric general anesthetics in the database of which 1085 (38.7%) were deemed as emergencies. There were no cases of failed intubation and seven cases of unanticipated difficult intubations (1:400 cases, 0.25% of all obstetric general anesthetics, 95% confidence interval 0.1-0.5%), six of which occurred during emergency surgery. There was an increase in obesity (p = .003) and ASA PS (p = .02) over the period of the study. The incidence of difficult intubation was not found to be significantly changed (p = .68).Despite an increase in ASA PS score and obesity, there was no increase in the incidence of difficult intubation in obstetric patients. Limitations of the study include its retrospective design, and the small number of difficult intubation cases identified.

In this paper, we propose a version of RSA encryption that uses the Chinese Remainder Theorem (CRT) for the purpose of concealing multiple plain-texts in one cipher-text. This scheme allows the sender to possibly send different information to multiple receivers, and each receiver is only able to decrypt the message intended for them. We prove the algorithm mathematically. Furthermore, we prove our algorithm secure against the chosen plain-text (CPA) attack. We also compare textbook RSA against our algorithm and show the security and size advantages. The new algorithm can also take advantage of current methods that speed up the decryption process of RSA. This scheme will become a basis for further one to many public key cryptosystems.

Study objective Open educational resources such as blogs are increasingly used for medical education. Gestalt is generally the evaluation method used for these resources; however, little information has been published on it. We aim to evaluate the reliability of gestalt in the assessment of emergency medicine blogs. Methods We identified 60 English-language emergency medicine Web sites that posted clinically oriented blogs between January 1, 2016, and February 24, 2016. Ten Web sites were selected with a random-number generator. Medical students, emergency medicine residents, and emergency medicine attending physicians evaluated the 2 most recent clinical blog posts from each site for quality, using a 7-point Likert scale. The mean gestalt scores of each blog post were compared between groups with Pearson's correlations. Single and average measure intraclass correlation coefficients were calculated within groups. A generalizability study evaluated variance within gestalt and a decision study calculated the number of raters required to reliably (>0.8) estimate quality. Results One hundred twenty-one medical students, 88 residents, and 100 attending physicians (93.6% of enrolled participants) evaluated all 20 blog posts. Single-measure intraclass correlation coefficients within groups were fair to poor (0.36 to 0.40). Average-measure intraclass correlation coefficients were more reliable (0.811 to 0.840). Mean gestalt ratings by attending physicians correlated strongly with those by medical students (r=0.92) and residents (r=0.99). The generalizability coefficient was 0.91 for the complete data set. The decision study found that 42 gestalt ratings were required to reliably evaluate quality (>0.8). Conclusion The mean gestalt quality ratings of blog posts between medical students, residents, and attending physicians correlate strongly, but individual ratings are unreliable. With sufficient raters, mean gestalt ratings provide a community standard for assessment.

What does the visual culture of early modern England, and the ways in which that culture articulated specific notions of corporeality, tell us about the actor’s body on Shakespeare’s stage? This article locates one answer to that question in the popular emblem books and the somewhat more rarefied cosmographical treatises of the day. Digging in these sources reveals an understanding of the body that is grounded first and foremost in corporeality – the body, before it was anything else, was matter. As such, I argue that the actor’s body on the early modern stage served as an instance of irrefutable and irreducible materiality, ‘lending’ its materiality to the abstractions and absences that Shakespeare’s theatre so readily ‘bodied forth.’However, as a wealth of scholarship on the body has suggested over the past few decades, things are not this simple. The body appears in these arenas as a very specific kind of matter, and matter itself is shown to have a complex relationship to ‘form’, or the immaterial realities of life. I argue here that the nature of the body-as-matter, and indeed of matter itself, is fruitfully understood in terms of two related early modern concepts: prima materia, and man as microcosm. These ideas were most in circulation in the distinct but kindred fields of alchemy and cosmography, and their visual manifestations offer a perspective on the theatrical body that does not reduce the body to simplematter, but still acknowledges its profound materiality, and the effect that the body-as-matter has on stage-work as a whole.

The incidence of metastatic lymph node involvement in prostate cancer has decreased with the advent of prostate specific antigen testing. Various algorithms have been designed to assess the probability of lymphatic involvement, resulting in the omission of lymph node dissection in many cases. However, recent reports suggest an underestimation of lymph node involvement. Meticulous lymph node dissection may provide a survival benefit by addressing micrometastatic disease. We analyzed the current literature on extended pelvic lymphadenectomy in prostate cancer.The pelvic lymphadenectomy literature was reviewed using a MEDLINE search, focusing on the prevalence of positive nodes, staging vs extended lymphadenectomy and therapeutic benefits.Staging pelvic lymphadenectomy provides valuable prognostic data and it may be therapeutic. Extended lymph node dissection increases the detection of positive nodes. The number of positive or negative nodes resected may increase survival. The observed survival benefits may be due to the elimination of micrometastatic disease.The role, indications and extent of lymphadenectomy remain controversial. Extended lymph node dissection should be performed in all patients at high risk to increase staging accuracy and provide a potential survival benefit. Detailed, meticulous dissection of the internal iliac lymph tissue is required. The benefit of extended lymph node dissection in patients at low risk remains to be determined.

In areas with dense landownership patterns, management of white-tailed deer (Odocoileus virginianus) depends upon collective decision making of landowners and hunters. To resolve conflicts associated with this commons dilemma, wildlife management associations (WMAs) have become a popular mechanism for coordinating wildlife management decisions in private land states, especially in Texas, USA. Social capital, represented by metrics such as trust, reciprocity, and community involvement, has been identified as an important determinant of the success of collaborative institutional arrangements. To determine the influence of social capital on the effectiveness of WMAs, we address 2 research questions: 1) do WMAs exhibit elements of social capital, and 2) what landowner characteristics affect elements of social capital within WMAs? We used a mail survey questionnaire to determine the effect of various factors on the activities and management practices in 4 WMAs in 2 regions in Texas: the Lower Post Oak Savannah (LPOS) and the Central Post Oak Savannah (CPOS). The LPOS landowners were members of larger associations, had generally acquired their land more recently, held more frequent meetings, and tended to have longer association membership than CPOS landowners, yet they exhibited lower social capital. The CPOS landowners owned significantly larger properties, and were predominantly absentee wealthy males that considered relaxation and hunting more important land uses than property ownership for a place to live. The smaller group size of the CPOS associations may be the most important factor in building and maintaining social capital. Intra-association trust, a primary measure of social capital, was positively influenced by the longevity of property ownership, the number of association meetings, the percentage of males in the association, and other factors. Conversely, negative influences on trust included absentee ownership and the proportion of woodland habitat present in each WMA. We suggest that deer are a common-pool resource whose populations are dependent upon collective action by stakeholders. Social capital building within landowner associations could facilitate the sustainable harvest of quality deer and possibly lead to cooperative management of other common-pool natural resources.

As nearly all of Texas’ rural lands are privately owned, landowner associations for the management of white-tailed deer and ground-water have become increasingly popular. Deer are a common-pool resource with transboundary characteristics, requiring landowner cooperation for effective management. Ground-water reserves are economically important to landowners, but are governed by the “rule of capture” whereby property rights are not defined. One ground-water association and four wildlife management associations (WMAs) were surveyed to characterize their member demographics, land use priorities, attitudes, and social capital. Members of the ground-water cooperative were part of a much larger, more heterogeneous, and more recently formed group than members of WMAs. They also placed greater importance on utilitarian aspects of their properties, as opposed to land stewardship for conservation as practiced by members of WMAs. If ground-water association members could be more locally organized with more frequent meetings, social capital and information sharing may be enhanced and lead to land stewardship practices for improved hydrologic functions and sustained ground-water supply. This, coupled with pumping rules assigned by the local ground-water district, could yield an effective strategy that is ecologically and hydrologicaly sound, and that allows rural provision of water supply to urban consumers.

Objective: To present the case of recurrent rhabdomyolysis in an active female Background: A healthy 21 year old female developed severe fatigue and peripheral edema in the upper extremities after an extreme exercise workout session. 4 ½ months later she participated in a similar exercise session with a personal trainer and experienced the same symptoms. Differential Diagnosis: In the initial case, upon physical examination and review of blood work a diagnosis of rhabdomyolysis was made. After the second exercise session athlete was diagnosed with recurrent rhabdomyolysis and was advised to seek treatment at the local emergency room. Treatment: In the initial case the athlete was told by medical personnel to increase fluid intake and rest. In the second case athlete was treated at the emergency room with IV fluids. Uniqueness: The athlete was female, and most cases of rhabdomyolysis occur in males. Athlete was treated for rhabdomyolysis and recurrent rhabdomyolysis, however these diagnosis were made 4 ½ months apart. Also, both cases appear to be the result of the same type of exercise session. Conclusion: There does not appear to be a definitive protocol for an accurate diagnosis of rhabdomyolysis. Guidelines for return to activity should be evaluated on a case by case basis, and a conservative increase in intensity of exercise is warranted to prevent a case of recurrent rhabdomyolysis.

Opportunities for wildlife undergraduates to engage in land conservation planning can bridge the gap between formal academic training and professional wildlife experiences. Land conservation plans are an important component in managing wildlife habitat. In 1995 state legislation offered Texas landowners the opportunity to remain under agricultural valuation (Texas House Bill 1358, Proposition 11, 1-d-1) by designating wildlife management activities as qualifying agricultural practices. To obtain a wildlife management tax valuation, a landowner must have an active, written wildlife management plan. Texas Parks and Wildlife Department (TPWD) biologists often provide technical guidance to landowners in this process. Allowing wildlife undergraduates to have an active role in this process offers a unique opportunity for them to gain practical “hands-on” experiences while improving their writing skills. Students enrolled in Wildlife Habitat Management and Conservation (WFSC 406) work in groups (3–4 students) to develop a management plan for 3 local landowners. In addition to writing an actual management plan, students gain experience in land surveying, vegetation sampling, GIS/GPS technology, and public speaking. Landowners receive 3 peer-reviewed management plans they can select from to implement on their property. Students assist TPWD biologists and Texas Cooperative Extension staff in providing technical guidance to local landowners. Wildlife education can be enhanced by integrating land conservation planning in the classroom via partnerships with natural resource agencies and landowners.

There are many published works on rotordynamics which detail the types of analyses that are carried out: critical speeds, stability assessment, and forced response. The purpose of this paper is to present a more complete analysis of an existing, academic rotor/bearing model, taken from a textbook, more like it would be carried out in an industrial setting. The advantage is that all parameters of the rotor model are well known so that there are minimal uncertainties. However, some published papers on rotordynamics, as discussed in this work, present an incomplete analysis. For example, they may report the calculated critical speeds but leave out the critical speed plot and mode shapes in favor of the Campbell diagram. They may model a Bernoulli Euler beam model of the shaft and neglect the additional terms in the Timoshenko beam model. These papers may show some unbalance response plots for one disk in the model but not report on the amplification factor. This paper gives a much more complete rotordynamics analysis of this common rotor/bearing model than other works. The full undamped rotor analysis is presented, including critical speeds, critical speed map, and undamped mode shapes. The stability analysis presents the full set of eigenvalues including both forward and backward modes as well as the complex mode shapes. The differences between the Bernoulli Euler beam model and the full Timoshenko beam model are shown for this rotor. Full unbalance response plots, in the horizontal and vertical directions, are presented as well as the response along the semi-major axis. The unbalance response plots have calculated amplitudes, phase angles and amplification factors. In addition to the standard rotordynamic analyses, a synchronously reduced modal truncation method is presented. This method is better suited to automation, when compared to most truncation methods that require significant intervention by the analyst. The maximum error was on the order of 0.01%. It is hoped that future publications will present the more complete analysis shown for this rotor/bearing system.Copyright © 2013 by ASME

A low concentration Building Integrated PhotoVoltaic (BIPV) window utilizing PV cells in conjunction with 3M Brand Prestige Window Film is presented. The goal was to provide a proof of concept showing how photovoltaics and the film can be integrated into windows to allow for both energy production and daylighting. Unlike most other BIPV windows, the PV cell angle is adjustable. The system was shown to be comparable to a typical window in terms of daylighting. Long-term energy production testing is needed for a conclusive analysis, but simulated results showed an increase in power compared to a vertical BIPV system.

To evaluate the safety of tubeless percutaneous nephrolithotomy in patients undergoing supracostal percutaneous renal access.Between October 1999 and October 2010, 302 patients underwent percutaneous nephrolithotomy via a supracostal access tract. Two hundred forty-eight (82.1%) patients had a nephrostomy tube placed at the end of the case and 54 (17.9%) did not. The medical records of both cohorts were compared regarding patient demographics (age, sex, body mass index, preoperative creatinine level), operative characteristics (estimated blood loss, length of stay, treatment efficacy), and complication rates (overall, thoracic, hemorrhage necessitating transfusion).Patient demographics did not differ between the tubeless and nephrostomy tube groups. Estimated blood loss was significantly less in the tubeless patients (67 mL vs 123 mL; P=0.019). The tubeless group had a shorter mean length of stay than the nephrostomy tube group (2.5 vs 3.4 days, P0.01). Treatment success was comparable between the two groups (tubeless 81.5% vs nephrostomy tube 77.8%; P=0.553). Overall complication (P=0.765) and blood transfusion (P=0.064) rates were equivalent. Chest complications were higher in the tubeless group (22.2%) compared with the nephrostomy tube patients (10.9%) (P=0.024). Nevertheless, chest complications necessitating intervention were not different (P=0.152).Tubeless supracostal percutaneous nephrolithotomy was associated with less intraoperative blood loss and a shorter hospital stay. Although the tubeless group experienced more chest complications overall, the need for intervention was no different among the two cohorts. Tubeless supracostal percutaneous nephrolithotomy appears safe.

The main goal of this study is to perform simulations of droplet dynamics using Truchas, a LANL-developed computational fluid dynamics (CFD) software, and compare them to a computational study of Hysing et al.[IJNMF, 2009, 60:1259]. Understanding droplet dynamics is of fundamental importance in liquid-liquid extraction, a process used in the nuclear fuel cycle to separate various components. Simulations of a single droplet rising by buoyancy are conducted in two-dimensions. Multiple parametric studies are carried out to ensure the problem set-up is optimized. An Interface Smoothing Length (ISL) study and mesh resolution study are performed to verify convergence of the calculations. ISL is a parameter for the interface curvature calculation. Further, wall effects are investigated and checked against existing correlations. The ISL study found that the optimal ISL value is 2.5{Delta}x, with {Delta}x being the mesh cell spacing. The mesh resolution study found that the optimal mesh resolution is d/h=40, for d=drop diameter and h={Delta}x. In order for wall effects on terminal velocity to be insignificant, a conservative wall width of 9d or a nonconservative wall width of 7d can be used. The percentage difference between Hysing et al.[IJNMF, 2009, 60:1259] and Truchas for the velocity profiles vary from 7.9% tomore » 9.9%. The computed droplet velocity and interface profiles are found in agreement with the study. The CFD calculations are performed on multiple cores, using LANL's Institutional High Performance Computing.« less

To reduce the vibration levels in a complex structure, the designer often needs to know how the vibrations in one part of a structure are transmitted to other parts at each interface of the connected components. A lumped-mass method and component mode synthesis is used to evaluate the power flow for vibrations in low-frequency range. The model mass and stiffness matrices are portioned into substructures separated by the interfaces whose power flow should be evaluated. The vibration modes of the substructure are divided into constrained and fixed interface modes corresponding to the interface and interior degree of freedoms, respectively. The effective interface mass criterion is used to rank the most dynamic important modes at each interface. The most important modes are preserved in a reduced model for computing the power flow. A numerical example of a linear system is used to illustrate the application of the new technique.Copyright © 2010 by ASME

Objectives To report 8 cases using the Yang-Monti channel with ileum for adult continent cutaneous urinary diversion. Methods From 2004 to 2006, 108 patients underwent urinary diversion, 8 of whom had a continent cutaneous reservoir using the Yang-Monti principle. Channels were created by transversely retubularizing 2 to 3 cm of ileum. Indications, technique, complications, and outcomes, such as continence and ease of channel catheterization, are reported. Results Five patients underwent a right colon reservoir urinary reconstruction after extirpative surgery. Orthotopic neobladders were not performed, owing to anatomic or oncologic concerns. Two additional patients underwent an augmentation, with 1 undergoing an Indiana pouch revision. All urinary reservoirs but 1 were connected to the umbilicus. Two strictures occurred, which were treated with in-office dilation. Incontinence was identified in 2 patients and successfully treated with dextran microspheres injections. All patients were continent at final follow-up. Seven patients continue to perform intermittent catheterization, and 1 patient is managed with an indwelling catheter, owing to comorbidities. Conclusions The Yang-Monti channel using ileum is an alternative as a neo-appendicoumbilicostomy in construction of continent cutaneous urinary diversion. The channel is surgically versatile and can be used in the creation of a right colon pouch when the appendix is unavailable.

An algorithm was developed for performing bilateral nephrectomies for specific indications before or at renal transplantation in patients with autosomal dominant polycystic kidney disease. Outcomes for the living donor arm of the algorithm are reported.Patients with autosomal dominant polycystic kidney disease and end stage renal disease were evaluated for transplantation. Patients with recurrent pyelonephritis, hemorrhage, pain, early satiety or kidneys that extended into the true pelvis underwent bilateral nephrectomies. Bilateral nephrectomies with concurrent renal transplantation were performed if a living renal donor was identified. If no living donor was identified, pre-transplantation bilateral nephrectomies were done and the patients were listed for cadaveric donor renal transplantation. The living renal donor arm of the algorithm was evaluated by comparing certain parameters for 15 and 17 patients with autosomal dominant polycystic kidney disease who underwent pre-transplantation and concurrent bilateral nephrectomies, respectively, including patient and graft survival, delayed graft function, graft function, length of stay for each surgery, transfusions and complications.No deaths, graft failures or delayed graft function occurred. In the delayed renal transplant group median time from nephrectomy to living donor transplantation was 124 days. Serum creatinine at discharge home and 1 year after transplantation for the pre-transplantation nephrectomy cohort was 2.0 and 1.3 mg/dl, respectively. Seven of the 17 patients with concurrent nephrectomy underwent transplantation before starting renal replacement therapy. A longer mean total hospital stay in the pre-transplantation nephrectomy cohort was the only statistically significance outcome variable.Selective bilateral nephrectomies at living donor renal transplantation results in decreased total length of stay without compromising patient or graft outcomes and it allows preemptive renal transplantation. Concurrent nephrectomy is safe and it further validates the algorithm for selective, concurrent bilateral nephrectomies for patients with autosomal dominant polycystic kidney disease who undergo living donor renal transplantation.

This case study examines the introduction of an ePortfolio requirement as a means of assessing student learning and program effectiveness. The Communication and Performance Studies major at Buena Vista University in Storm Lake, Iowa, began piloting the use of an assessment ePortfolio in the spring of 2003 and has since fully implemented it as a program requirement. Although the potential of ePortfolios is still being realized, research suggests the benefit of involving students in program assessment. Case studies are helpful to further define and articulate the emerging literature on assessment ePortfolios. Using qualitative research methods, strengths and weaknesses of this ePortfolio implementation are identified, and areas of improvement are discussed.

Targeting of cyclooxygenase-2 (COX-2) for cancer chemoprevention is well supported for several tumor types, most notably colon cancer. In contrast, the data for its role in prostate cancer carcinogenesis are correlative only. Thus, we compared the COX-2 expression, activity, and effects of inhibition in prostate cancer cells on COX-2-dependent colon cancer cells. COX-2 levels in benign and malignant human prostate tissue were determined by immunohistochemistry. Compared to colon cancer cells, prostate cancer cells expressed lower levels of COX-2, produced less PGE 2 , and were resistant to selective COX-2 inhibition. Examination of benign prostatic epithelium from prostatectomy samples demonstrated rare foci of COX-2. Whereas, human prostate cancer sections were uniformly negative for COX-2. In conclusion, these studies indicate the lack of a putative role for COX-2 in prostate cancer development. Direct evidence for the involvement of COX-2 in prostate cancer carcinogenesis is desperately needed.

A 66-year-old man with androgen-independent prostate cancer was treated with abarelix, a gonadotropin-releasing hormone antagonist, for 20 weeks in an experimental protocol. He did not respond to therapy, but his serum prostate-specific antigen level dropped from 15.8 ng/mL to a confirmed 0.8 ng/mL after abarelix was stopped. His prostate-specific antigen level did not return to greater than 15.8 ng/mL for 14 months. This is the first report of a withdrawal response after therapy with a gonadotropin-releasing hormone antagonist, a new class of agents for prostate cancer. Additional observations are needed to determine whether this is an isolated case or a harbinger of a more common phenomenon.