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Commensality, the act of eating together, when organized around facilitated discussion is an evidence-based intervention that can promote engagement and reduce physician burnout. The purpose of this pilot study is to evaluate the feasibility, acceptance, and impact of a commensality intervention for physicians. The Commensality Intervention was based on a Mayo Clinic model that consisted of 6, 2-hour dinner meetings at local restaurants over 6 months with facilitated discussion. Seven physicians participated, with controls matched by specialty and career stage. All completed the Maslach Burnout Inventory and Areas of Worklife Survey (MBI/AWS) at baseline, 6 months, and 12 months. Results were analyzed using Mann-Whitney tests for comparison of intervention group members to controls. At baseline, 4 of 7 in the intervention group and 3 of 7 controls met criteria for burnout. At 6 months, MBI improved in all dimensions: emotional exhaustion (EE) 24.3 to 17.2; depersonalization (DP) 7.1 to 5.1; personal accomplishment (PA) 40.0 to 43.3. Improvement in EE was significantly greater for intervention group members vs. controls ( P =.015). Similarly, every AWS dimension (except reward) improved in the intervention group, with significant improvements in Workload ( P =.012), Control ( P =.027), and Community ( P =.039). At 12 months, improvements in EE (21.6), DP (5.3) and PA (42.7) persisted but were attenuated, with none of the MBI/AWS changes from baseline statistically significant. Findings suggest significant improvements in physician burnout following the intervention, with attenuation at 12-months. Results will be used to support the broader implementation of commensality within the group practice., Competing Interests: None of the authors identify any conflict of interest., (©Copyright 2024 by University Health Partners of Hawai‘i (UHP Hawai‘i).)

Background: High-quality workplace-based assessments are essential for competency-based surgical education. We explored education leaders' perceptions regarding faculty competence in assessment., Methods: Surgical education leaders were surveyed regarding which areas faculty needed improvement, and knowledge of assessment tools. Respondents were queried on specific skills regarding (a)importance in resident/medical student education (b)competence of faculty in assessment and feedback., Results: Surveys (n = 636) were emailed, 103 responded most faculty needed improvement in: verbal (86%) and written (83%) feedback, assessing operative skill (49%) and preparation for procedures (50%). Cholecystectomy, trauma laparotomy, inguinal herniorrhaphy were "very-extremely important" in resident education (99%), but 21-24% thought faculty "moderately to not-at-all" competent in assessment. This gap was larger for non-technical skills. Regarding assessment tools, 56% used OSATS, 49% Zwisch; most were unfamiliar with all non-technical tools., Summary: These data demonstrate a significant perceived gap in competence of faculty in assessment and feedback, and unfamiliarity with assessment tools. This can inform faculty development to support competency-based surgical education., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Stressors during surgical residency training are common and can contribute to impaired technical performance, medical errors, health problems, physician burnout, and career turnover. This survey of general surgery recent graduates and chief residents examined threats to resident health and well-being. An electronic survey composed of multiple-choice, checkbox, dropdown, and open-ended questions was developed to determine the most stressful general surgery residency year, sources of the stress, and potential interventions to manage resident well-being. The survey was sent to five program directors across the United States to be forwarded to chief residents and recent graduates less than five years from graduation. Twenty-three residents and recent graduates responded to the survey. Seventy percent reported they "never" got enough sleep, and 39% reported they did not have a healthy lifestyle. Financial concerns were the most frequently cited source of stress. During post-graduate-years (PGY) 1 and 2, residents were most likely to fear hurting a patient or being "in over their head." In PGY-3, residents were most likely to consider leaving the residency program. The current findings suggest that each year of general surgery residency is linked with certain stressors, and no year is particularly stressful relative to the other years. There can be more research and efforts to focus on additional PGY-specific training and supervision, as well as added general measures to promote resident health and financial stability throughout all years. Regarding stress mitigation, residents may benefit from faculty, peer, and community interaction rather than from formal professional counseling., (©Copyright 2020 by University Health Partners of Hawai‘i (UHP Hawai‘i).)

Spinal cord injury remains one of the most devastating forms of traumatic injury. The purpose of this study was to characterize the clinical characteristics of spinal cord injury patients and the geographic location where the injury occurred in the state of Hawai'i. Spinal cord injury cases from 2009-2017 were identified using the State Trauma Registry, which included demographics, mechanism of injury, and outcomes. In 1170 spinal cord injury cases, the second most frequent etiology was an ocean-wave related incident. Over half of wave related spinal cord injury occurred on ten beaches on four islands. Compared to other mechanisms, patients with wave related spinal cord injury were significantly less likely to be Hawai'i residents (15%), screen positive for alcohol (4%), or have an injury in the lower thoracic or lumbar region (4%). These patients were also less likely to die (1%) and more likely to be discharged to home (66%). Wave related incidents are a major cause of spinal cord injury in Hawai'i, disproportionately affecting visitors. Education focused toward middle-aged male visitors at beaches with moderate to severe shorebreak may reduce the incidence of injury., Competing Interests: None of the authors identify any conflict of interest. The views expressed are those of the authors and do not necessarily represent the official views of the Queen's Medical Center or the Hawai‘i State Department of Health., (©Copyright 2019 by University Health Partners of Hawai‘i (UHP Hawai‘i).)

Fibroadenomas are common benign tumors of the female breast. In the appropriate clinical setting, they are often managed expectantly without excision. Rarely, cancer may arise within a fibroadenoma, and this diagnosis mandates prompt treatment for malignancy. We present the case of a 70-year-old Samoan woman with ductal carcinoma in situ (DCIS) arising within a fibroadenoma. Health care practitioners should be aware of the possibility, particularly in older women, of finding carcinoma within a fibroadenoma, which informs the rationale for prompt surgical evaluation and follow up of all breast masses., Competing Interests: None of the authors identify a conflict of interest.

Background: We hypothesized that medical experts would concur the American College of Surgeons/Association for Surgical Education Medical Student Simulation-based Surgical Skills Curriculum ("ACS/ASE Curriculum") could be used to teach and assess Entrustable Professional Activities (EPAs)., Methods: A "crosswalk" was created between ACS/ASE Curriculum modules and eight EPAs. Medical education experts participated in a Delphi process regarding feasibility of using the modules for teaching and assessing EPAs., Results: Twenty-eight educators from six clinical fields participated. There was consensus that five of the EPAs could be taught and assessed by the ACS/ASE Curriculum. A median of nine hours per month outside the surgical clerkship was recommended for skills training., Conclusions: The ACS/ASE Curriculum lays the framework for implementing select EPAs into medical student education. Experts recommended increased time for skills training with incorporation of the modules into the first three years of medical education, with assessments planned in the third to fourth years., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Background: Development of Level III trauma centers in a regionalized system facilitates early stabilization and prompt transfer to a higher level center. The resources to care for patients at Level III centers could also reduce the burden of interfacility transfers. We hypothesized that the development and designation of Level III centers in an inclusive trauma system resulted in lower rates of transfer, with no increase in morbidity or mortality among the non-transferred patients., Methods: State trauma registry data from January 2009 through September 2015 were examined from five rural hospitals that transfer patients to our highest (Level II) trauma center and resource hospital. These five rural hospitals began receiving state support in 2010 to develop their trauma programs and were subsequently verified and designated Level III centers (three in 2011, two in 2013). Multivariate logistic regression was used to examine the adjusted odds of patient transfers and adverse outcomes, while controlling for age, gender, penetrating mechanism, presence of a traumatic brain injury, arrival by ambulance, and category of Injury Severity Score. The study period was divided into "Before" Level III center designation (2009-2010) and "After" (2011-2015)., Results: 7,481 patient records were reviewed. There was a decrease in the proportion of patients who were transferred After (1,281/5,737) compared to Before (516/1,744) periods (22% vs. 30%, respectively). After controlling for the various covariates, the odds of patient transfer were reduced by 32% (p < 0.0001) during the After period. Among non-transferred patients, there were no significant increases in adjusted odds of mortality, or hospitalizations of seven days or more, Before versus After., Conclusions: Development of rural Level III trauma centers in a regionalized system can significantly reduce the need for transfer to a remote, higher level trauma center. This may benefit the patient, family, and trauma system, with no adverse effect upon patient outcome., Level of Evidence: Epidemiological, level III.

Background: Half of the US states have legalized medical cannabis (marijuana), some allow recreational use. The economic and public health effects of these policies are still being evaluated. We hypothesized that cannabis legalization was associated with an increase in the proportion of motor vehicle crash fatalities involving cannabis-positive drivers, and that cannabis use is associated with high-risk behavior and poor insurance status., Methods: Hawaii legalized cannabis in 2000. Fatality Analysis Reporting System data were analyzed before (1993-2000) and after (2001-2015) legalization. The presence of cannabis (THC), methamphetamine, and alcohol in fatally injured drivers was compared. Data from the state's highest level trauma center were reviewed for THC status from 1997 to 2013. State Trauma Registry data from 2011 to 2015 were reviewed to evaluate association between cannabis, helmet/seatbelt use, and payor mix., Results: THC positivity among driver fatalities increased since legalization, with a threefold increase from 1993-2000 to 2001-2015. Methamphetamine, which has remained illegal, and alcohol positivity were not significantly different before versus after 2000. THC-positive fatalities were younger, and more likely, single-vehicle accidents, nighttime crashes, and speeding. They were less likely to have used a seatbelt or helmet. THC positivity among all injured patients tested at our highest level trauma center increased from 11% before to 20% after legalization. From 2011 to 2015, THC-positive patients were significantly less likely to wear a seatbelt or helmet (33% vs 56%). They were twice as likely to have Medicaid insurance (28% vs 14%)., Conclusion: Since the legalization of cannabis, THC positivity among MVC fatalities has tripled statewide, and THC positivity among patients presenting to the highest level trauma center has doubled. THC-positive patients are less likely to use protective devices and more likely to rely on publically funded medical insurance. These findings have implications nationally and underscore the need for further research and policy development to address the public health effects and the costs of cannabis-related trauma., Level of Evidence: Prognostic, level III.

Background: Training in ultrasound is variable among residents and practicing traumatologists. Focused Assessment with Sonography in Trauma (FAST) may be underused in non-urbanized areas, possibly due to lack of training., Methods: State trauma registry data from January 2014-June 2016 were reviewed for FAST results. Trauma practitioners were surveyed querying training, confidence, and obstacles to performing FAST., Results: 12,855 records revealed highest FAST use at the urban Level II center (39%, p < 0.0001). Despite similar injury patterns, non-urban/Level III centers' frequency of FAST was only 1-28%. 39 practitioners were surveyed, those with training (54%) were more likely to use FAST (p < 0.05). 61% of practitioners outside the Level II center cited lack of confidence in their ability to perform FAST as the primary reason for omitting the exam., Conclusions: FAST is relatively underused in non-urbanized areas of the state. Lack of confidence in ability to perform FAST was cited as the primary barrier., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Background: There are currently no courses that focus specifically on surgical education research. A needs assessment of surgical educators is required to best design these courses., Methods: A cross-sectional survey-based study on all faculty members of the Association for Surgical Education was done to determine their education research needs., Results: The overall response rate was 15% and the majority of the 78 respondents were physicians (63%) in their mid- to late career stage (65%). Participants thought research topics should be taught at an advanced level in a workshop format. Senior educators were less interested than junior educators in learning to create conceptual frameworks (p = 0.038) and presenting their research at national meetings (p = 0.014)., Conclusions: Surgical educators desire more training in education research techniques that are taught in a workshop format at a national surgical education meeting. These workshops may lay the groundwork for a nationally recognized certificate in surgical education research., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Helmet use reduces injury severity, disability, hospital length of stay, and hospital charges in motorcycle riders. The public absorbs billions of dollars annually in hospital charges for unhelmeted, uninsured motorcycle riders. We sought to quantify, on a statewide level, the healthcare burden of unhelmeted motorcycle and moped riders. We examined 1,965 emergency medical service (EMS) reports from motorcycle and moped crashes in Hawai'i between 2007-2009. EMS records were linked to hospital medical records to assess associations between vehicle type, helmet use, medical charges, diagnoses, and final disposition. Unhelmeted riders of either type of vehicle suffered more head injuries, especially skull fractures (adjusted odds ratio (OR) of 4.48, P < .001, compared to helmeted riders). Motorcyclists without helmets were nearly three times more likely to die (adjusted OR 2.85, P = .001). Average medical charges were almost 50% higher for unhelmeted motorcycle and moped riders, with a significant ( P = .006) difference between helmeted ($27,176) and unhelmeted ($40,217) motorcycle riders. Unhelmeted riders were twice as likely to self-pay (19.3%, versus 9.8% of helmeted riders), and more likely to have Medicaid or a similar income-qualifying insurance plan (13.5% versus 5.0%, respectively). Protective associations with helmet use are stronger among motorcyclists than moped riders, suggesting the protective effect is augmented in higher speed crashes. The public financial burden is higher from unhelmeted riders who sustain more severe injuries and are less likely to be insured.

Background: Briefing of the trauma team before patient arrival is unstructured in many centers. We surveyed trauma teams regarding agreement on patient care priorities and evaluated the impact of a structured, physician-led briefing on concordance during simulated resuscitations., Methods: Trauma nurses at our Level II center were surveyed, and they participated in four resuscitation scenarios, randomized to "briefed" or "nonbriefed." For nonbriefed scenarios, nurses independently reviewed triage sheets with written information. Briefed scenarios had a structured 4-minute physician-led briefing reviewing triage sheets identical to nonbriefed scenarios. Teams included three to four nurses (subjects) and two to four confederates (physicians, respiratory therapists). Each team served as their own control group. Confederates were blinded to nurses' briefed or nonbriefed status. Immediately before, and at the midpoint of each scenario, nurses estimated patients' morbidity and mortality and ranked the top 3 of 16 designated immediate care priorities. Briefed and nonbriefed groups' responses were compared for (1) agreement using intraclass correlation coefficient, (2) concordance with physicians' responses using the Fisher exact test, (3) teamwork via T-NOTECHS ratings by nurses and physicians using t-test, and (4) time to complete clinical tasks using t test., Results: Thirty-eight nurses participated. Ninety-seven percent "agreed/strongly agreed" briefing is important, but only 46% agreed briefing was done well. Comparing briefed versus nonbriefed scenarios, nurses' estimation of morbidity and mortality in the briefed scenarios showed significantly greater agreement with each other and with physicians' answers (p < 0.01). Rank lists also better agreed with each other (intraclass correlation coefficient, 0.64 vs 0.59) and with physicians' answers in the briefed scenarios. T-NOTECHS Leadership ratings were significantly higher in the briefed scenarios (3.70 vs 3.39; p < 0.01). Time to completion of key clinical tasks was significantly faster for one of the briefed scenarios., Conclusions: Discordant perceptions of patient care goals was frequently observed. Structured physician-led briefing seemed to improve interprofessional team concordance, leadership, and task completion in simulated trauma resuscitations.

The oomycete Phytophthora infestans causes late blight of potato, which can completely destroy the crop. Therefore, for the past 160 years, late blight has been the most important potato disease worldwide. The identification of cultivars with high and durable field resistance to P. infestans is an objective of most potato breeding programs. This type of resistance is polygenic and therefore quantitative. Its evaluation requires multi-year and location trials. Furthermore, quantitative resistance to late blight correlates with late plant maturity, a negative agricultural trait. Knowledge of the molecular genetic basis of quantitative resistance to late blight not compromised by late maturity is very limited. It is however essential for developing diagnostic DNA markers that facilitate the efficient combination of superior resistance alleles in improved cultivars. We used association genetics in a population of 184 tetraploid potato cultivars in order to identify single nucleotide polymorphisms (SNPs) that are associated with maturity corrected resistance (MCR) to late blight. The population was genotyped for almost 9000 SNPs from three different sources. The first source was candidate genes specifically selected for their function in the jasmonate pathway. The second source was novel candidate genes selected based on comparative transcript profiling (RNA-Seq) of groups of genotypes with contrasting levels of quantitative resistance to P. infestans. The third source was the first generation 8.3k SolCAP SNP genotyping array available in potato for genome wide association studies (GWAS). Twenty seven SNPs from all three sources showed robust association with MCR. Some of those were located in genes that are strong candidates for directly controlling quantitative resistance, based on functional annotation. Most important were: a lipoxygenase (jasmonate pathway), a 3-hydroxy-3-methylglutaryl coenzyme A reductase (mevalonate pathway), a P450 protein (terpene biosynthesis), a transcription factor and a homolog of a major gene for resistance to P. infestans from the wild potato species Solanum venturii. The candidate gene approach and GWAS complemented each other as they identified different genes. The results of this study provide new insight in the molecular genetic basis of quantitative resistance in potato and a toolbox of diagnostic SNP markers for breeding applications.

Background: Trauma care requires coordinating an interprofessional team, with formative feedback on teamwork skills. We hypothesized nurses and surgeons have different perceptions regarding roles during resuscitation; that nurses' teamwork self-assessment differs from experts', and that video debriefing might improve accuracy of self-assessment., Methods: Trauma nurses and surgeons were surveyed regarding resuscitation responsibilities. Subsequently, nurses joined interprofessional teams in simulated trauma resuscitations. After each resuscitation, nurses and teamwork experts independently scored teamwork (T-NOTECHS). After video debriefing, nurses repeated T-NOTECHS self-assessment., Results: Nurses and surgeons assumed significantly more responsibility by their own profession for 71% of resuscitation tasks. Nurses' overall T-NOTECHS ratings were slightly higher than experts'. This was evident in all T-NOTECHS subdomains except "leadership," but despite statistical significance the difference was small and clinically irrelevant. Video debriefing did not improve the accuracy of self-assessment., Conclusions: Nurses and physicians demonstrated discordant perceptions of responsibilities. Nurses' self-assessment of teamwork was statistically, but not clinically significantly, higher than experts' in all domains except physician leadership., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Background: The objective of this study was to analyze the potential of prostate magnetic resonance imaging (MRI) and MRI/transrectal ultrasound-fusion biopsies to detect and to characterize significant prostate cancer (sPC) in the anterior fibromuscular stroma (AFMS) and in the transition zone (TZ) of the prostate and to assess the accuracy of multiparametric MRI (mpMRI) and biparametric MRI (bpMRI) (T2w and diffusion-weighted imaging (DWI))., Methods: Seven hundred and fifty-five consecutive patients underwent prebiopsy 3 T mpMRI and transperineal biopsy between October 2012 and September 2014. MRI images were analyzed using PIRADS (Prostate Imaging-Reporting and Data System). All patients had systematic biopsies (SBs, median n=24) as reference test and targeted biopsies (TBs) with rigid software registration in case of MRI-suspicious lesions. Detection rates of SBs and TBs were assessed for all PC and sPC patients defined by Gleason score (GS)⩾3+4 and GS⩾4+3. For PC, which were not concordantly detected by TBs and SBs, prostatectomy specimens were assessed. We further compared bpMRI with mpMRI., Results: One hundred and ninety-one patients harbored 194 lesions in AFMS and TZ on mpMRI. Patient-based analysis detected no difference in the detection of all PC for SBs vs TBs in the overall cohort, but in the repeat-biopsy population TBs performed significantly better compared with SBs (P=0.004 for GS⩾3+4 and P=0.022 for GS⩾4+3, respectively). Nine GS⩾4+3 sPCs were overlooked by SBs, whereas TBs missed two sPC in men undergoing primary biopsy. The combination of SBs and TBs provided optimal local staging. Non-inferiority analysis showed no relevant difference of bpMRI to mpMRI in sPC detection., Conclusions: MRI-targeted biopsies detected significantly more anteriorly located sPC compared with SBs in the repeat-biopsy setting. The more cost-efficient bpMRI was statistically not inferior to mpMRI in sPC detection in TZ/AFMS.

Drug and alcohol use is a pervasive problem in the general population and in those requiring anesthesia for an operation. History and screening can help delineate those who may be acutely intoxicated or chronic drug and alcohol users. Both acute intoxication and chronic abuse of these substances present challenges for anesthetic management during and after an operation. The clinician should be aware of problems that may be encountered during any part of anesthesia or postoperative care., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Purpose: Multiparametric magnetic resonance imaging and magnetic resonance imaging targeted biopsy may improve the detection of clinically significant prostate cancer. However, standardized prospective evaluation is limited., Materials and Methods: A total of 294 consecutive men with suspicion of prostate cancer (186 primary, 108 repeat biopsies) enrolled in 2013 underwent 3T multiparametric magnetic resonance imaging (T2-weighted, diffusion weighted, dynamic contrast enhanced) without endorectal coil and systematic transperineal cores (median 24) independently of magnetic resonance imaging suspicion and magnetic resonance imaging targeted cores with software registration (median 4). The highest Gleason score from each biopsy method was compared. McNemar's tests were used to evaluate detection rates. Predictors of Gleason score 7 or greater disease were assessed using logistic regression., Results: Overall 150 cancers and 86 Gleason score 7 or greater cancers were diagnosed. Systematic, transperineal biopsy missed 18 Gleason score 7 or greater tumors (20.9%) while targeted biopsy did not detect 11 (12.8%). Targeted biopsy of PI-RADS 2-5 alone overlooked 43.8% of Gleason score 6 tumors. McNemar's tests for detection of Gleason score 7 or greater cancers in both modalities were not statistically significant but showed a trend of superiority for targeted primary biopsies (p=0.08). Sampling efficiency was in favor of magnetic resonance imaging targeted prostate biopsy with 46.0% of targeted biopsy vs 7.5% of systematic, transperineal biopsy cores detecting Gleason score 7 or greater cancers. To diagnose 1 Gleason score 7 or greater cancer, 3.4 targeted and 7.4 systematic biopsies were needed. Limiting biopsy to men with PI-RADS 3-5 would have missed 17 Gleason score 7 or greater tumors (19.8%), demonstrating limited magnetic resonance imaging sensitivity. PI-RADS scores, digital rectal examination findings and prostate specific antigen greater than 20 ng/ml were predictors of Gleason score 7 or greater disease., Conclusions: Compared to systematic, transperineal biopsy as a reference test, magnetic resonance imaging targeted biopsy alone detected as many Gleason score 7 or greater tumors while simultaneously mitigating the detection of lower grade disease. The gold standard for cancer detection in primary biopsy is a combination of systematic and targeted cores., (Copyright © 2015 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.)

Background: Reports regarding helmets in motorcycle crashes have been limited by the lack of data across the spectrum of injury outcomes, generally excluding low-severity injuries that do not require further medical treatment. We hypothesized that the protective effect of helmets may be underestimated in studies that focused only on patients who arrive at a trauma center and that it may differ depending on whether the crash involved a motorcycle or moped., Methods: The emergency medical service reports of 2,553 crash patients treated from 2007 to 2009 were linked to police crash reports, hospital billing data, death certificates, and the Fatal Analysis Reporting System for a more complete description of the crashes throughout the state., Results: The number of unhelmeted riders (n = 1,674) was nearly double those who were helmeted (n = 879). Multivariate logistic regression models estimated 45% greater odds of a hospital admission (vs. no hospital treatment or a discharge from the emergency department setting) among unhelmeted riders, compared with helmeted riders. Unhelmeted riders also had an adjusted odds of a fatal injury that was more than double that of helmeted riders (odds ratio, 2.71; 95% confidence interval, 1.68-4.46). Stratified analyses showed that these protective associations between helmet use and medical disposition were apparent only among motorcyclists., Conclusion: The magnitude of the protective associations between helmets and medical outcomes was generally greater than that reported by other studies. Motorcyclists seem to benefit from helmet use more than moped riders. This data could be used to promote helmet use through education and public policy., Level of Evidence: Prognostic/epidemiologic study, level III.

Objective: To show the benefit of trocar-sharpened needles for image-guided prostate biopsy compared with standard bevelled needles in patients., Materials and Methods: Twenty-four men underwent magnetic resonance imaging-targeted fusion-guided transperineal saturation prostate biopsy, each with half standard bevelled and half trocar-sharpened needles. All taken biopsies were scored (1=worse to 5=best) by one urologist for the following criteria. (1) Accuracy of matching between planned and performed biopsy. (2) Histologic quality of the sample. (3) Elegance, which is the easiness to take the biopsy in proper time, planned position, and best histologic quality. Afterward, the histologic sample quality was evaluated by a blinded pathologist. To show a possible training effect, blinded untrained junior residents performed biopsies in four men (103 cores)., Results: Overall, 600 single biopsies were analyzed. The trocar-sharpened needles demonstrated a significantly (p<0.05) better scoring for accuracy and elegance rated by the urologist. The histologic quality scored by the pathologist was superior. Moreover, significantly lower target errors with trocar-sharpened needles were achieved by untrained residents, but not by the experienced user., Conclusion: Using trocar-sharpened needles helps urologists to perform targeted prostate biopsy more elegantly and accurately. In addition, the histopathologic sample quality was superior, which may directly improve diagnostic certainty. There is an undeniable training effect in image-guided biopsy and unexperienced users can significantly reduce target errors with trocar-sharpened needles.

Non-technical skills (teamwork) assessment is used to improve competence during training for interprofessional trauma teams. We hypothesized non-technical skills assessment is less reliable for large size teams, and evaluated team size effects during teamwork training. Small-teams (n = 5; 5-7 members) and Large-teams (n = 6; 8-9 members) participated in three simulation-based trauma team training scenarios. Following each scenario, teamwork was scored by participating trauma attending physicians (TA), non-participating critical care trauma nurses (CRN), and two expert teamwork debriefers (E), using the Trauma Nontechnical Skills Assessment tool (T-NOTECHS). Large-team scores by TA and CRN were higher than E scores (P < .003); small-team scores did not differ by rater. Small-team inter-observer agreement was substantial (ICC = 0.60); large-team agreement was low (ICC = 0.29). E and TA scores showed no concordance, whereas E and CRN scores showed poor concordance for large teams (ICC = 0.41, r = 0.53, P = .02). By contrast, correlation between E and TA (ICC = 0.52, r = 0.80, P < .001) as well as E and CRN (ICC = 0.57, and r = 0.65, P < .01) for small teams was high. Team size should be considered in team-training design, and when using teamwork rating instruments such as T-NOTECHS for assessment of simulated or actual trauma teams. Modified rating scales and enhanced training for raters of large groups versus small groups may be warranted.

Background: A modified nontechnical skills (NOTECHS) scale for trauma (T-NOTECHS) was developed to teach and assess teamwork skills of multidisciplinary trauma resuscitation teams. In this study, T-NOTECHS was evaluated for reliability and correlation with clinical performance., Methods: Interrater reliability (intraclass correlation coefficient) and correlation with the speed and completeness of resuscitation tasks were assessed during simulation-based teamwork training and during actual trauma resuscitations., Results: For T-NOTECHS ratings done in real time, intraclass correlation coefficients were .44 for simulated and .48 for actual resuscitations. Reliability was higher (intraclass correlation coefficient = .71) for video review of resuscitations. Better T-NOTECHS scores were correlated with better performance during simulations, evidenced by a greater number of completed resuscitation tasks (r = .50, P < .01) and faster time to completion (r = -.38, P < .05) In actual resuscitations, T-NOTECHS ratings improved after teamwork training (P < .001). Higher T-NOTECHS scores were correlated with better clinical performance, evidenced by faster resuscitation (r = -.13, P < .05) and fewer unreported resuscitation tasks (r = -.16, P < .05)., Conclusions: Improvement in T-NOTECHS scores after teamwork training, and correlation with clinical parameters in simulated and actual trauma resuscitations, suggest its clinical relevance. Further evaluation, aiming to improve reliability, may be warranted., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Objective: Evaluate the impact of a team training curriculum for residents and multidisciplinary trauma team members on team communication, coordination and clinical efficacy of trauma resuscitation., Design: Prospective, cohort intervention comparing pre- vs. post-training performance. The intervention was a human patient simulator (HPS)-based, in situ team training curriculum, comprising a one-hour web based didactic followed by HPS training in the emergency department (ED). Teams were trained in multidisciplinary groups of 5-8 persons. Each HPS session included three fifteen minute scenarios with immediate video-enabled debriefing. Structured debriefing and teamwork assessment was performed with a modified NOTECHS scale for trauma (T-NOTECHS). Teams were assessed for performance changes during HPS-based training, as well as in actual trauma resuscitations., Setting: The Queen's Trauma Center (Level II); the primary teaching hospital for the University of Hawaii Surgical Residency., Participants: 137 multidisciplinary trauma team members, including residents (n = 24), ED and trauma attending physicians, nurses, respiratory therapists, and ED technicians., Results: During HPS-based training sessions, significant improvements in teamwork ratings, and in clinical task speed and completion rates were noted between the first and the last scenario.244 real-life blunt trauma resuscitations were observed for six months before and after training. There was a significant improvement in mean teamwork scores from the pre-to post-training resuscitations. Moreover, there were significant improvements in the objective parameters of speed and completeness of resuscitation. This was manifest by a 76% increase in the frequency of near-perfect task completion (≤ 1 unreported task), and a reduction in the mean overall ED resuscitation time by 16%., Conclusions: A relatively brief (four-hour) HPS-based curriculum can improve the teamwork and clinical performance of multidisciplinary trauma teams that include surgical residents. This improvement was evidenced both in simulated and actual trauma settings, and across teams of varying composition. HPS-based trauma teamwork training appears to be an educational method that can impact patient care., (Copyright © 2011 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.)

Measurement of blood volume (BV) may guide fluid and red blood cell management in critically ill patients when capillary leak from shock and fluid resuscitation makes assessment of intravascular volume difficult. This is a prospective randomized trial of critically ill surgical patients with septic shock, severe sepsis, severe respiratory failure, and/or cardiovascular collapse. The control group received fluid management based on pulmonary artery catheter parameters and red blood cell transfusions based on hematocrit values. The BV group received fluid and red blood cell transfusions based on BV analyses in addition to pulmonary artery catheter parameters. Blood volume was measured using the radioisotope tracer technique with iodine 131-labeled albumin. This allowed direct measurement of plasma volume and calculation of the red blood cell volume. The control group was blinded to the BV results. There were statistically significantly more times when the control group (compared with the BV group) demonstrated hypervolemia (48% vs. 37%) and red blood cell deficiency (33% vs. 16%). There was a delay in red blood cell transfusions administered to the control group by 1.5 +/- 2 days at which time the abnormality became clinically evident. Blood volume analyses provided additional information to the clinicians resulting in a change in treatment in 44% of the time to patients randomized to the BV group. The mortality rates were significantly different between the two groups (8% for the BV group and 24% in the control group; P = 0.03). Blood volume measurements allowed the physicians to promptly treat physiologic disturbances in both red blood cell volume and plasma volume, resulting in improved survival.

Background: Traumatic injuries to the retrohepatic vena cava are typically fatal. Emergent access to this area is difficult and patients typically exsanguinate before the injury can be identified and fixed., Objective: To report the use of an atriocaval shunt in the repair of an injury to the retrohepatic vena cava from a gunshot wound., Case Report: A 24-year-old man was shot in his right chest suffering a penetrating injury to the liver and inferior vena cava. Surgical repair was performed with the aid of an atriocaval shunt fashioned from a chest tube. He survived and recovered without incident., Conclusion: Atriocaval shunting maybe a life-saving option for uncontrolled hemorrhage from injuries to the retrohepatic vena cava.

In Drosophila miranda the small multigene family of the larval cuticle protein (Lcp1-4) genes resides on the evolving neo-X and neo-Y sex chromosome pair while in the sibling species Drosophila pseudoobscura and Drosophila persimilis the gene cluster is inherited autosomally. The neo-Y chromosomal Lcp1, Lcp2 and Lcp4 genes are, as previously shown by us, not expressed and only Lcp3 is expressed at a strongly reduced level. As a first step in understanding the evolutionary mechanism(s) transforming an autosome into a dosage compensated X we analysed the expression behaviour and promoter structure of the Lcp1-4 genes on the neo-X. The normalized relative expression levels reveal that all four neo-X chromosomal Lcp genes in D. miranda males, including Lcp3, are already dosage compensated.

Background: Education in obtaining informed consent, combined with technical training using a stepwise approach, may improve resident knowledge of, confidence in, and frequency of obtaining consent for bedside procedures., Methods: Surgical trainees were randomized to receive a lecture on obtaining informed consent. Knowledge of, confidence in, and frequency of obtaining consent were assessed. Subsequent first-year residents received combined technical and consent training using a stepwise approach. Residents listed key steps for procedures before and after training, were observed for consent and technical competency on patients, and were assessed on frequency of obtaining consent by follow-up chart review., Results: Knowledge and confidence improved after lecture instruction, but consent rate (21%) did not. Stepwise training increased resident awareness of obtaining informed consent as a key step (19% to 77%) and increased frequency of obtaining consent (89% for proctored procedures and 79% in follow-up)., Conclusions: Education alone improves knowledge but not practice of obtaining consent. Teaching the consent process concomitantly with technical training may increase awareness and performance of obtaining informed consent for bedside procedures.

Background: We developed a personal digital assistant (PDA)-based program to assess compliance with our medical student work hours policy, and to correlate work hours with sleep and performance., Methods: Medical students on surgery clerkship logged real-time work and sleep hours for 1 week. Estimated work hours, clinical evaluations, and score on the National Board of Medical Examiners (NBME) surgery examination were recorded., Results: Thirty-seven students logged work hours, which correlated poorly with estimated work hours and sleep hours. The majority of students overestimated work hours by a mean of 19.5 hours. Twenty-four students transgressed written policy. Increased in-hospital study hours correlated with improved clinical ratings but poorer NBME examination scores. Increased operating room hours correlated with higher NBME examination scores., Conclusions: Medical students inaccurately estimate work hours; a PDA-based log facilitates hours monitoring. Unenforced work hour policies are frequently transgressed. Work activity patterns, but not total work hours, correlated with outcomes on standardized written tests and clinical ratings.

Suppression of recombination is the prerequisite for stable genetically determined sex systems. A consequence of suppression of recombination is the strong bias in the distribution of transposable elements (TEs), mostly retrotransposons. Our results and those from others indicate that the major force driving the degeneration of Y chromosomes are retrotransposons in remodelling former euchromatic chromosome structures into heterochromatic ones. We put forward the following hypotheses. (1) A massive accumulation of retrotransposons occurs early in non-recombining regions. (2) Heterochromatic nucleation centres are formed as a genomic defence mechanism against invasive parasitic elements. The newly established nucleation centres become epigenetically inherited. (3) Spreading of heterochromatin from the nucleation centres into flanking regions induces, in an adaptive process, transcriptional gene silencing of neighbourhood genes that could either be still intact or in an already eroded condition. (4) Constitutive silenced genes are not under the same genetic selection pressure as active genes. They are more exposed to the decay process. (5) Gene dosage balance is re-established by the parallel evolution of dosage compensation mechanisms.

Background: Surgeons infrequently provide smoking cessation counseling for patients, in part because they lack training to do so. We investigated the efficacy of 2 methods of teaching smoking cessation counseling to surgical residents., Methods: Residents' knowledge and attitude toward smoking cessation counseling were assessed by written test. Counseling skills were assessed with standardized patients. Residents were randomized for smoking cessation education: a "Role-play" group received a 1-hour lecture plus an hour of role-playing. An evidence-based medicine (EBM) group attended a 1- hour EBM journal club on related articles. Changes in residents' knowledge, attitude, and skills were assessed after education., Results: Sixteen residents completed the study. After either form of education, residents demonstrated significant improvements in knowledge, attitude, and skills in smoking cessation counseling. There was no significant difference in improvement between the EBM and Role-play groups., Conclusions: A brief educational intervention can significantly improve residents' knowledge, attitude, and counseling skills for smoking cessation.

Many eukaryotic taxa inherit a heteromorphic sex chromosome pair. It is a generally accepted hypothesis that the sex chromosome pair is derived from a pair of homologous autosomes that has developed after the occurrence of a sex differentiator in an evolutionary process into two structurally and functionally different partners. In most of the analyzed systems the occurrence of the dominant sex differentiator is paralleled by the suppression of recombination within and close by that region. The recombinational isolation can spread in an evolutionary selection process from neighboring regions finally over the whole chromosome. Suppression of recombination strongly biases the distribution of retrotransposons in the genome. Our results and that from others indicate that the major force driving the evolution of Y chromosomes are retrotransposons, remodeling euchromatic chromosome structures into heterochromatic ones. In our model, intact or already eroded retrotransposons become trapped due to their inherent transposition mechanisms in non-recombining regions. The massive accumulation of retrotransposons interferes strongly with the activity of genes. We hypothesize that Y chromosome degeneration is a stepwise evolutionary process: (1) Massive accumulation of retrotransposons occurs in the non-recombining regions. (2) Heterochromatic nucleation centers are formed as a consequence of genomic defense against invasive parasitic elements; the established nucleation centers become epigenetically inherited. (3) Spreading of heterochromatin from the nucleation centers into flanking regions induces in an adaptive process gene silencing of neighbored genes that could either be still intact or in an already eroded condition, e.g., showing point mutations, deletions, insertions; the retroelements should be subjects to the same forces of deterioration as the genes themselves. (4) Constitutive silenced genes are not committed to the same genetic selection pressure as active genes and therefore more exposed to the decay process. (5) Gene dosage balance is reestablished by the parallel evolution of dosage compensation mechanisms. The evolving secondary sex chromosomes, neo-X and neo-Y, of Drosophila miranda are revealed to be a unique and potent model system to catch the evolutionary Y deterioration process in progress.

Purpose: To evaluate the prognostic relevance of the volume of nodal metastatic disease in colorectal cancer patients., Patients and Methods: One hundred node-positive patients with T2 or T3 carcinoma of the colon or rectum after routine histologic examination of the regional nodes were studied. The metastatic tumor was measured with an ocular micrometer, and the tumor volume was determined., Results: The mean lymph node metastatic tumor volume was 5.1 +/- 4.99 mm(3) (range, 0.05 to 83,434 mm(3)). There was only a weak positive correlation with number of nodes involved with metastatic disease and tumor volume in nodes (r =.45). Median follow-up was 39 months (range, 1 to 87 months). The number of nodes was highly predictive of outcome. Individuals with one to three positive nodes had a substantially better survival than individuals with four or more positive nodes (P <.001). The volume of nodal metastatic disease correlated with outcome (P =.019). Patients dying as a result of disease had substantially greater mean metastatic nodal volume than those who were alive (3,705 v 1,783 mm(3); P =.036). However, the total metastatic nodal volume did not, independent of positive nodes or number of positive nodes, predict outcome. Individuals with micrometastatic nodal volume did not have improved survival when compared with individuals with macrometastatic nodal volume (P =.79)., Conclusion: The number of nodes involved with metastatic tumor, rather the volume of metastatic involvement of the regional lymph nodes, predicts outcome. These results suggest that micrometastatic disease may have a similar prognosis as macrometastatic disease when the same number of lymph nodes are involved with metastatic tumor.

A 28-year-old woman with an infiltrating ductal carcinoma in the upper outer quadrant of the left breast diagnosed by excisional biopsy underwent lumpectomy, intraoperative lymphatic mapping, and sentinel node dissection. This was followed by an immediate completion axillary node dissection using a hand-held gamma probe and isosulfan blue to map the lymphatics. Preoperative breast lymphoscintigraphy showed drainage into the axilla and an apparent area of radiocolloid accumulation in the inferior hemisphere of the left breast. Because our protocol called only for removal of axillary sentinel nodes, the inferior hemisphere radiocolloid accumulation was not removed. The patient did not complete local regional therapy with breast irradiation and developed a mass in the inferior hemisphere of the left breast, which on biopsy was shown to be metastatic breast cancer in an intramammary lymph node. This case illustrates the potential value of breast lymphoscintograms to identify unusual sites of lymphatic drainage that may prove to be clinically relevant.

It is generally assumed that the sex chromosomes developed from a pair of homologs. Over evolution, the proto-Y chromosome, with a very short differential segment, matured in its final stage into a heterochromatic and, for the most part, genetically eroded Y chromosome. The constraints on the evolution of the proto-Y chromosome have been speculated upon since the sex chromosomes were discovered. Several models have been suggested. Drosophila miranda has proved to be a unique and potent model system to study Y-chromosome evolution. We use selected test genes distributed along the neo-Y chromosome as entry gates to analyze the molecular mechanisms involved in the process of Y-chromosome evolution. Here, we report our findings on the Krüppel gene (Kr), which is located distally on the neo-sex chromosome pair., (Copyright 2001 S. Karger AG, Basel)

Background: The feasibility of intraoperative lymphatic mapping and sentinel lymphadenectomy (SLND) in settings other than high-volume specialized clinics has been questioned. We sought to determine the feasibility of SLND in a university-affiliated private teaching hospital., Methods: A multidisciplinary sentinel node program was established to include surgeons, nuclear medicine physicians, and pathologists. Within this program, 79 patients with cutaneous melanoma underwent attempted SLND after cutaneous lymphoscintigraphy (CL), between January 1994 and December 1998. All sentinel nodes were examined by hematoxylin-eosin staining and determined whether negative for evidence metastatic disease by both S-100 and HMB 45 immunohistochemical staining., Results: CL was successful in 77 (97%) of 79 patients. A total of 88 lymphatic basins were found to be at risk for metastatic disease by CL. SLND was not successful in the two patients who did not have a successful CL. Sentinel nodes were identified in all but three patients with the remaining 88 lymphatic basins (technical success, 97%). There was one false negative in this group of patients (approximately 1%)., Conclusions: SLND is a highly accurate way of staging the regional node basin. Our technical success rates and false-negative rates indicate the feasibility of this approach in settings other than high-volume specialty clinics.

Y chromosome evolution is characterized by the expansion of genetic inertness along the Y chromosome and changes in the chromosome structure, especially the tendency of becoming heterochromatic. It is generally assumed that the sex chromosome pair has developed from a pair of homologues. In an evolutionary process the proto-Y-chromosome, with a very short differential segment, develops in its final stage into a completely heterochromatic and to a great extends genetically eroded Y chromosome. The constraints evolving the Y chromosome have been the objects of speculation since the discovery of sex chromosomes. Several models have been suggested. We use the exceptional situation of the neo-Y in Drosophila miranda to analyze the molecular process in progress involved in Y chromosome evolution. We suggest that the first steps in the switch from a euchromatic proto-Y-chromosome into a completely heterochromatic Y chromosome are driven by the accumulation of transposable elements, especially retrotransposons inserted along the evolving nonrecombining part of the Y chromosome. In this evolutionary process trapping and accumulation of retrotransposons on the proto-Y-chromosome should lead to conformational changes that are responsible for successive silencing of euchromatic genes, both intact or already mutated ones and eventually transform functionally euchromatic domains into genetically inert heterochromatin. Accumulation of further mutations, deletions, and duplications followed by the evolution and expansion of tandem repetitive sequence motifs of high copy number (satellite sequences) together with a few vital genes for male fertility will then represent the final state of the degenerated Y chromosome.

On the basis of chromosomal homology, the Amylase gene cluster in Drosophila miranda must be located on the secondary sex chromosome pair, neo-X (X2) and neo-Y, but is autosomally inherited in all other Drosophila species. Genetic evidence indicates no active amylase on the neo-Y chromosome and the X2-chromosomal locus already shows dosage compensation. Several lines of evidence strongly suggest that the Amy gene cluster has been lost already from the evolving neo-Y chromosome. This finding shows that a relatively new neo-Y chromosome can start to lose genes and hence gradually lose homology with the neo-X. The X2-chromosomal Amy1 is intact and Amy2 contains a complete coding sequence, but has a deletion in the 3'-flanking region. Amy3 is structurally eroded and hampered by missing regulatory motifs. Functional analysis of the X2-chromosomal Amy1 and Amy2 regions from D. miranda in transgenic D. melanogaster flies reveals ectopic AMY1 expression. AMY1 shows the same electrophoretic mobility as the single amylase band in D. miranda, while ectopic AMY2 expression is characterized by a different mobility. Therefore, only the Amy1 gene of the resident Amy cluster remains functional and hence Amy1 is the dosage compensated gene.

Y chromosome degeneration is characterized by structural changes in the chromosome architecture and expansion of genetic inertness along the Y chromosome. It is generally assumed that the heteromorphic sex chromosome pair has developed from a pair of homologues. Several models have been suggested. We use the unique situation of the secondary sex chromosome pair, neo-Y and neo-X (X2), in Drosophila miranda to analyze molecular mechanisms involved in the evolutionary processes of Y chromosome degeneration. Due to the fusion of one of the autosomes to the Y chromosome (about 2 Mya), a neo-Y chromosome and a neo-X chromosome, designated X2, were formed. Thus, formerly autosomal genes are inherited now on a pair of sex chromosomes in D. miranda. Analyzing DNA sequences from the X2 and neo-Y region, we observed a massive accumulation of DNA insertions on the neo-Y chromosome. From the analysis of several insertion elements, we present compelling evidence that the first step in Y chromosome degeneration is driven by the accumulation of transposable elements, especially retrotransposons. An enrichment of these elements along an evolving Y chromosome could account for the switch from a euchromatic into a heterochromatic chromatin structure.

We have cloned a novel transposable element from the neo-Y chromosome of Drosophila miranda. The size of the element, designated as TRAM, is 3.452 bp, including on both sides long terminal direct repeats (LTRs) of 372 bp, respectively. The element is flanked by a 5-bp target site duplication, ATATG. The putative primer binding site (PBS) for minus-strand priming is complementary to 18 nucleotides of the 3'-end of tRNA(Trp). Data base screens for DNA sequence identities were negative, apart from the sequence motif of the PBS. The deduced amino acid sequence from the large ORF does not reveal identities described for other transposons. In situ hybridizations with TRAM subclones show a biased distribution in the genome, with a massive accumulation of TRAM in the neo-Y chromosome, while the former homologue, the X2 chromosome is devoid of TRAM sites. The enriched occurrence of the TRAM element at the evolving neo-Y chromosome of D.miranda adds compelling evidence in favor of the view that Y chromosome degeneration is driven by the accumulation of transposable elements.

The larval cuticle protein genes (Lcps) represent a multigene family located at the right arm of the metacentric autosome 2 (2R) in Drosophila melanogaster. Due to a chromosome fusion the Lcp locus of Drosophila miranda is situated on a pair of secondary sex chromosomes, the X2 and neo-Y chromosome. Comparing the DNA sequences from D. miranda and D. melanogaster organization and the gene arrangement of Lcp1-Lcp4 are similar, although the intergene distances vary considerably. The greatest difference between Lcp1 and Lcp2 is due to the occurrence of a pseudogene in D. melanogaster which is not present in D. miranda. Thus the cluster of the four Lcp genes existed already before the separation of the melanogaster and obscura group. Intraspecific homogenizations of different cluster units must have occurred repeatedly between the Lcp1/Lcp2 and Lcp3/Lcp4 sequence types. The most obvious example is exon 2 of the Lcp3 gene in D. miranda, which has been substituted by the corresponding section of the Lcp4 gene rather recently. The homogenization must have occurred before the translocation which generated the neo-Y chromosome. Lcp3 of D. melanogaster has therefore no orthologous partner in D. miranda. Rearrangements in the promoter regions of the D. miranda Lcp genes have generated new, potentially functional CAAT-box motifs. Since three of the Lcp alleles on the neo-Y are not expressed and Lcp3 is expressed only at a reduced level, it is suggestive to speculate that the rearrangements might be involved as cis-regulatory elements in the up-regulation of the X2-chromosomal Lcp alleles, in Drosophila an essential process for dosage compensation. The Lcp genes on the neo-Y chromosome have accumulated more base substitutions than the corresponding alleles on the X2.

The larval cuticle proteins (LCPs) are encoded by a multigene family, Lcp1-4, located at the right arm of the metacentric autosome 2 (2R) in Drosophila melanogaster. Due to a chromosome fusion the Lcp locus of Drosophila miranda is situated on a pair of secondary sex chromosomes, the X2 and neo-Y chromosomes. Comparing the deduced amino acid sequences of the autosomal D. melanogaster loci with the sex-chromosomal loci of D. miranda, we were able to trace the evolution of the Lcp loci with respect to their different chromosomal inheritance. The length of the signal peptide is conserved in all four LCPs, while the size of the mature LCPs varies. Conserved protein motifs became obvious from the alignment, indicating regions of structural and functional importance. Analyzing intra- and interspecific sequence similarities of the Lcp gene families allowed us to reconstruct the phylogeny of the gene cluster. Alignment with cuticle amino acid sequences originating from divergent insect species reveals motifs already present in the primordial insect LCPs. These motifs indicate different levels of constraint acting during the evolution of the LCPs.

In polytene chromosome squashes from the fruit fly Drosophila melanogaster, the single, dosage-compensated X chromosome in males can be distinguished from the autosomes by the presence of an isoform of histone H4 acetylated at lysine 16, H4.Ac16. We have used H4.Ac16 as a marker to examine the evolving relationship between dosage compensation and sex chromosome composition in species of Drosophila with one (D. melanogaster), two (D. pseudoobscura) or three (D. miranda) identifiable X chromosome arms. In each case, we find that H4.Ac16 is distributed as discrete, closely spaced bands along the entire length of each X chromosome, the only exception being the X2 chromosome of D. miranda in which a terminal region constituting about 10% of the chromosome by length is not labelled with anti-H4.Ac16 antibodies. We conclude that, with this exception, dosage compensation extends along the X chromosomes of all three species. As D. pseudoobscura and D. miranda diverged only about 2 Mya, the spread of dosage-compensated loci along X2 has been rapid, suggesting that regional changes rather than piecemeal, gene-by-gene, changes may have been involved.

Changes in patterns of gene induction by myeloid lineage cells following multiple exposures to endotoxin (lipopolysaccharide; LPS) is a feature of LPS tolerance. To further understand the mechanism of this phenomenon we describe studies using stably transfected Chinese hamster ovary cell lines that express human CD14 (CHO-hCD14). Using NF-kappa B activation as a measure of LPS-induced cell activation we show that a single treatment with LPS renders CHO-hCD14 cells tolerant to subsequent challenge with LPS, but not with other stimuli such as tumor necrosis factor. Tolerance may result from the induction of gene(s) that control LPS-induced signaling pathways and here we suggest that such genes may be found in the group of immediate, early response genes characterized by the protein phosphatase 3CH134. The CHO-hCD14 cell lines provide a novel model system to further explore the mechanism of endotoxin tolerance.

The deposition of titanium in regional lymph nodes was studied after insertion of endosseous, plasma-spray-coated titanium screw implants in a total of 19 beagle dogs. Five additional animals with no implants served as the control group. After killing the animals 9 months postoperatively, the regional lymph nodes were carefully excised, and samples were prepared for histologic examination. Other samples were used to identify foreign particles by energy-dispersive x-ray analysis and for measurement of the titanium concentration in the tissue by flameless atomic absorption spectroscopy. Very fine foreign-body particles could be seen in the histologic sections, and they were identified as titanium by energy-dispersive x-ray analysis. The atomic absorption analysis for titanium revealed a significantly higher concentration in the group with implants. The presence of very fine, poorly attached particles on the plasma-sprayed titanium surface suggests that these particles may be mechanically dislodged from the surface on insertion of the implants. This suggests that the fine particles may be transported by phagocytes to the regional lymph nodes, where they could be found without any signs of inflammation or foreign-body reaction.

Endotoxic shock is associated with a coagulopathy, organ failure, and death. Tissue factor (TF) expression by monocytes exposed to bacterial endotoxin (lipopolysaccharide [LPS]) may mediate the coagulopathy and contribute to the high mortality of this disease. We examined the role of the LPS-binding protein (LBP)/CD14 receptor pathway in the LPS induction of TF expression in human monocytic THP-1 cells and peripheral blood monocytes. In THP-1 cells, the threshold concentration of LPS required to induce TF activity in serum-free medium was reduced 20-fold by purified LBP, which also enhanced TF mRNA synthesis. Similarly, monocytes cultured in the presence of serum were induced to express TF antigen at LPS concentrations 100 times lower than monocytes cultured in serum-free medium. An anti-LBP monoclonal antibody indicated that this effect was dependent on the presence of LBP in serum. LPS/LBP induction of TF activity and TF antigen expression in these monocytic cells were also inhibited by an anti-CD14 monoclonal antibody, indicating a requirement for the CD14 receptor. Thus, we suggest that low levels of LPS (5 to 100 pg/mL) present during sepsis induce TF expression in monocytes via the LBP/CD14-dependent pathway.

Exposure of rabbit peritoneal exudate macrophages (PEM) or whole blood to picomolar concentrations of LPS induces adaptation or hyporesponsiveness to LPS. Because of the importance of plasma LPS-binding protein (LBP) and the macrophage cell membrane protein CD14 in recognition of LPS, we examined the effect of LBP on LPS-induced adaptation in PEM. PEM exposed to LPS in the presence of LBP for 8 h were markedly less responsive to subsequent stimulation by LPS than monocytes/macrophages (M phi) adapted in the absence of LBP. LPS-induced expression of TNF was sharply reduced in LBP-LPS-adapted PEM, but in contrast these cells remained fully responsive to Staphylococcus aureus peptidoglycan. We considered that specific hyporesponsiveness in LPS-adapted M phi or in blood monocytes could be due to decreased expression of CD14 or diminished binding of LBP-LPS complexes to CD14. However, flow cytometry analysis revealed only minimal reduction of CD14 expression or CD14-dependent binding of a fluorescent LPS derivative when normo- and hyporesponsive cells were compared. These results show that complexes of LPS and LBP are more effective than LPS alone in inducing adaptation to LPS, and LPS-induced hyporesponsiveness probably results from changes in cellular elements distinct from CD14 that are involved in either LPS recognition or LPS-specific signal transduction.

We have investigated the mechanistic aspects of inactivation of the major larval cuticle protein genes (Lcp1-4) in Drosophila miranda during Y chromosome evolution. The Lcp genes are located on the X2 and neo-Y chromosomes in D. miranda but are autosomally inherited in all other Drosophila species investigated so far. In the neo-Y chromosome all four Lcp loci are embedded within a dense cluster of transposable elements. The X2 Lcp1-4 loci are expressed, while the Y chromosomal Lcp3 locus shows only reduced activity and the Lcp1, Lcp2, and Lcp4 are completely inactive. Our results suggest that Lcp1 and Lcp3 loci on the degenerating Y chromosome of D. miranda are silenced by neighboring transposable elements. These observations support our assumption that the first step in Y chromosome degeneration is the successive silencing of Y chromosomal loci caused by trapping and accumulation of transposons.

Evolutionary changes during the process of sex chromosome differentiation in Drosophila miranda are associated with massive DNA rearrangements. Comparing the DNA structure of the larval cuticle protein (Lcp) region from the X2 and neo-Y chromosome pair, we observed insertions, deletions and a large duplication at the neo-Y chromosomal locus. The duplication encompasses a complete copy of the neo-Y allele of Lcp2, and the ISY3 and the ISY4 insertion sequences. The latter was identified as a retrotransposon, termed TRIM. ISY3 shows DNA sequence similarity to P element homologs identified in the Drosophila obscura species group. We were interested in mechanistic aspects generating the duplication. We cannot exclude unequivocally that unequal sister-chromatid exchange could give rise to the observed duplication; however, recombination is a rare event in Drosophila males. Location and sequence of the retrotransposon TRIM served as molecular markers allowing us to reconstruct two intrachromosomal transposition events that could lead to the observed duplication.

In Drosophila miranda, the larval cuticle protein (Lcp) genes are located on the X2 and Y chromosomes, while in other Drosophila species the Lcp genes are inherited on the autosomes. We chose the D. miranda species as a model system to analyze the molecular bases of Y chromosome degeneration, a phenomenon observed in many species. DNA sequence analysis of the Y chromosomal Lcp gene locus reveals dense clustering of trapped retrotransposons. Once inserted at the Y chromosomal location they cannot easily be eliminated by unequal crossing-over, as recombination is a rare event in Drosophila males. In addition, we have uncovered an example of a completely inactive allele on the degenerating Y chromosome. The existence of such inactive Y-specific alleles was originally predicted in H. J. Muller's model for Y chromosome degeneration. We demonstrate that the Y chromosomal Lcp4 allele is no longer transcribed. From the divergence in DNA sequence organization of former homologous chromosome regions we conclude that changes in chromosome structure and destruction of genetic activity in degenerating Y chromosomes are based on one major mechanism, which operates by means of transposable elements.