Understanding Physician's Perspectives on AI in Health Care: Protocol for a Sequential Multiple Assignment Randomized Vignette Study

BACKGROUND

As the availability and performance of artificial intelligence (AI)-based clinical decision support (CDS) systems improve, physicians and other care providers poised to be on the front lines will be increasingly tasked with using these tools in patient care and incorporating their outputs into clinical decision-making processes. Vignette studies provide a means to explore emerging hypotheses regarding how context-specific factors, such as clinical risk, the amount of information provided about the AI, and the AI result, may impact physician acceptance and use of AI-based CDS tools. To best anticipate how such factors influence the decision-making of frontline physicians in clinical scenarios involving AI decision-support tools, hypothesis-driven research is needed that enables scenario testing before the implementation and deployment of these tools.

OBJECTIVE

This study's objectives are to (1) design an original, web-based vignette-based survey that features hypothetical scenarios based on emerging or real-world applications of AI-based CDS systems that will vary systematically by features related to clinical risk, the amount of information provided about the AI, and the AI result; and (2) test and determine causal effects of specific factors on the judgments and perceptions salient to physicians' clinical decision-making.

METHODS

US-based physicians with specialties in family or internal medicine will be recruited through email and mail (target n=420). Through a web-based survey, participants will be randomized to a 3-part "sequential multiple assignment randomization trial (SMART) vignette" detailing a hypothetical clinical scenario involving an AI decision support tool. The SMART vignette design is similar to the SMART design but adapted to a survey design. Each respondent will be randomly assigned to 1 of the possible vignette variations of the factors we are testing at each stage, which include the level of clinical risk, the amount of information provided about the AI, and the certainty of the AI output. Respondents will be given questions regarding their hypothetical decision-making in response to the hypothetical scenarios.

RESULTS

The study is currently in progress and data collection is anticipated to be completed in 2024.

CONCLUSIONS

The web-based vignette study will provide information on how contextual factors such as clinical risk, the amount of information provided about an AI tool, and the AI result influence physicians' reactions to hypothetical scenarios that are based on emerging applications of AI in frontline health care settings. Our newly proposed "SMART vignette" design offers several benefits not afforded by the extensively used traditional vignette design, due to the 2 aforementioned features. These advantages are (1) increased validity of analyses targeted at understanding the impact of a factor on the decision outcome, given previous outcomes and other contextual factors; and (2) balanced sample sizes across groups. This study will generate a better understanding of physician decision-making within this context.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/54787.

Academic machine learning researchers' ethical perspectives on algorithm development for health care: a qualitative study

OBJECTIVES

We set out to describe academic machine learning (ML) researchers' ethical considerations regarding the development of ML tools intended for use in clinical care.

MATERIALS AND METHODS

We conducted in-depth, semistructured interviews with a sample of ML researchers in medicine (N = 10) as part of a larger study investigating stakeholders' ethical considerations in the translation of ML tools in medicine. We used a qualitative descriptive design, applying conventional qualitative content analysis in order to allow participant perspectives to emerge directly from the data.

RESULTS

Every participant viewed their algorithm development work as holding ethical significance. While participants shared positive attitudes toward continued ML innovation, they described concerns related to data sampling and labeling (eg, limitations to mitigating bias; ensuring the validity and integrity of data), and algorithm training and testing (eg, selecting quantitative targets; assessing reproducibility). Participants perceived a need to increase interdisciplinary training across stakeholders and to envision more coordinated and embedded approaches to addressing ethics issues.

DISCUSSION AND CONCLUSION

Participants described key areas where increased support for ethics may be needed; technical challenges affecting clinical acceptability; and standards related to scientific integrity, beneficence, and justice that may be higher in medicine compared to other industries engaged in ML innovation. Our results help shed light on the perspectives of ML researchers in medicine regarding the range of ethical issues they encounter or anticipate in their work, including areas where more attention may be needed to support the successful development and integration of medical ML tools.

Self-reported influences on willingness to receive COVID-19 vaccines among physically ill, mentally ill, and healthy individuals

OBJECTIVE

Individuals with mental and physical disorders have been disproportionately affected by adverse health outcomes due to the COVID-19 pandemic, and yet vaccine hesitancy persists despite clear evidence of health benefits. Therefore, our study explored factors influencing willingness to receive a COVID-19 vaccine.

METHODS

Individuals with mental illness (n = 332), physical illness (n = 331), and no health issues (n = 328) were recruited via Amazon Mechanical Turk. Participants rated willingness to obtain a fully approved COVID-19 vaccine or a vaccine approved only for experimental/emergency use and influences in six domains upon their views. We examined differences by health status.

RESULTS

Participants across groups were moderately willing to receive a COVID-19 vaccine. Perceived risk was negatively associated with willingness. Participants differentiated between vaccine risk by approval stage and were less willing to receive an experimental vaccine. Individuals with mental illness rated risk of both vaccines similarly to healthy individuals. Individuals with physical illness expressed less willingness to receive an experimental vaccine. Domain influences differently affected willingness by health status as well as by vaccine approval status.

CONCLUSIONS

Our findings are reassuring regarding the ability of people with mental disorders to appreciate risk in medical decision-making and the ability of people of varied health backgrounds to distinguish between the benefits and risks of clinical care and research, refuting the prevailing notions of psychiatric exceptionalism and therapeutic misconception. Our findings shine a light on potential paths forward to support vaccine acceptance.

Maternal Perceptions of Safeguards for Research Involving Children

The vitality of clinical research and the health of the public relies on continued efforts to engage children in clinical research in a fully protected and ethically robust manner. Parents serve as proxy decision-makers assessing the risks and benefits of any given study in order to do what is in the best interest of their child. This study investigated maternal perceptions of research safeguards and mothers' willingness to enroll their children in clinical research studies. We hypothesized that mothers' perceptions of the protectiveness of safeguard procedures utilized in clinical research would be associated with mothers' willingness to enroll their children in research studies with such safeguards. Through a survey conducted via Amazon Mechanical Turk, mothers were asked to rate the perceived protectiveness of four safeguard procedures (confidential data coding, data and safety monitoring boards (DSMBs), institutional review boards (IRBs), and informed consent) and the degree to which they were willing to have their child participate in research studies in the presence of each of the four safeguard procedures. Respondents generally perceived safeguard procedures to be protective. Mothers' trust in researchers' honesty positively impacted perceptions of the protectiveness of research safeguard procedures and willingness to enroll children in research. Mothers of only healthy children perceived research safeguards to be more protective than mothers with at least one child with at least one health issue. This study provides insight into whether maternal perceptions of the protectiveness of different safeguard procedures are associated with mothers' willingness to enroll their children in research.

Influence of Dispositional Optimism on Ethically Salient Research Perspectives: A Pilot Study

Research participants should be drawn as fairly as possible from the potential volunteer population. Underlying personality traits are underexplored as factors influencing research decision-making. Dispositional optimism, known to affect coping, physical health, and psychological well-being, has been minimally studied with respect to research-related attitudes. We conducted an exploratory, online survey with 151 individuals (with self-reported mental illness [n = 50], physical illness [n = 51], or neither [n = 50]) recruited via MTurk. We evaluated associations between dispositional optimism (assessed with the Life Orientation Test-Revised) and general research attitudes, perceived protectiveness of five research safeguards, and willingness to participate in research using safeguards. Strongly optimistic respondents expressed more positive research attitudes and perceived four safeguards as more positively influencing willingness to participate. Optimism was positively associated with expressed willingness to participate in clinical research. Our findings add to a limited literature on the influence of individual traits on ethically salient research perspectives.

Eating disorders early app use mediates treatment effect on clinical improvement

OBJECTIVE

Eating disorders (EDs) contribute considerably to the global burden of disease. However, most affected individuals do not receive treatment. Mobile apps present an enormous opportunity to increase access to mental healthcare services. This study examined whether the degree of usage of a self-help app for EDs mediated the app's effects on the clinical response by individuals with EDs.

METHOD

App usage measures included the total number of cognitive-behavioral meal logs, total number of days spent using the app, and the last day the app was used during the study period. Mediation analysis was performed using the MacArthur framework.

RESULTS

All usage variables met the analytic requirements for testing mediation (group means (sd) for app and standard app, respectively: logs = 74 (108) vs. 51.4 (88.1), days spent = 14.3 (17.5) vs. 10.6 (15.0), p-values from Wilcox rank sum tests p < .01). Regression coefficients indicated mediation effects. The mediation effects demonstrated support that increased engagement (as measured by logs and time spent on the app) was related to an increased likelihood of achieving a significant clinical change by the end of the trial.

DISCUSSION

Greater and longer engagement in an ED app mediates its efficacy in terms of ED remission.

Factors Influencing Perceived Helpfulness and Participation in Innovative Research: A Pilot Study of Individuals with and without Mood Symptoms

Little is known about how individuals with and without mood disorders perceive the inherent risks and helpfulness of participating in innovative psychiatric research, or about the factors that influence their willingness to participate. We conducted an online survey with 80 individuals (self-reported mood disorder [n = 25], self-reported good health [n = 55]) recruited via MTurk. We assessed respondents' perceptions of risk and helpfulness in study vignettes associated with two innovative research projects (intravenous ketamine therapy and wearable devices), as well as their willingness to participate in these projects. Respondents with and without mood disorders perceived risk similarly across projects. Respondents with no mood disorders viewed both projects as more helpful to society than to research volunteers, while respondents with mood disorders viewed the projects as equally helpful to volunteers and society. Individuals with mood disorders perceived ketamine research, and the two projects on average, as more helpful to research volunteers than did individuals without mood disorders. Our findings add to a limited empirical literature on the perspectives of volunteers in innovative psychiatric research.

Perceived protectiveness of research safeguards and influences on willingness to participate in research: A novel MTurk pilot study

Little is known about how individuals with mood disorders view the protectiveness of research safeguards, and whether their views affect their willingness to participate in psychiatric research. We conducted an online survey with 80 individuals (self-reported mood disorder [n = 25], self-reported good health [n = 55]) recruited via MTurk. We assessed respondents' perceptions of the protectiveness of five common research safeguards, as well as their willingness to participate in research that incorporates each safeguard. Perceived protectiveness was strongly related to willingness to participate in research for four of the safeguards. Our findings add to a limited literature on the motivations and perspectives of key stakeholders in psychiatric research.

Artificial Intelligence and Suicide Prevention: A Systematic Review of Machine Learning Investigations

Suicide is a leading cause of death that defies prediction and challenges prevention efforts worldwide. Artificial intelligence (AI) and machine learning (ML) have emerged as a means of investigating large datasets to enhance risk detection. A systematic review of ML investigations evaluating suicidal behaviors was conducted using PubMed/MEDLINE, PsychInfo, Web-of-Science, and EMBASE, employing search strings and MeSH terms relevant to suicide and AI. Databases were supplemented by hand-search techniques and Google Scholar. Inclusion criteria: (1) journal article, available in English, (2) original investigation, (3) employment of AI/ML, (4) evaluation of a suicide risk outcome. N = 594 records were identified based on abstract search, and 25 hand-searched reports. N = 461 reports remained after duplicates were removed, n = 316 were excluded after abstract screening. Of n = 149 full-text articles assessed for eligibility, n = 87 were included for quantitative synthesis, grouped according to suicide behavior outcome. Reports varied widely in methodology and outcomes. Results suggest high levels of risk classification accuracy (>90%) and Area Under the Curve (AUC) in the prediction of suicidal behaviors. We report key findings and central limitations in the use of AI/ML frameworks to guide additional research, which hold the potential to impact suicide on broad scale.

Attitudes of Mothers Regarding Willingness to Enroll Their Children in Research

This study assessed mothers' perspectives regarding research involvement by their children, factors that might affect perceptions of research risks, and attitudes regarding willingness to enroll children in research. Participants completed a survey on Amazon Mechanical Turk. Mothers were less inclined to enroll children in research involving procedures posing higher risk (regression coefficient = -0.51). Mothers without mental health issues with children without health issues were more sensitive to risk than mothers without mental health issues with children with health issues (estimated difference = 0.49). Mothers with mental health issues were more willing than mothers without mental health issues to enroll children in research (regression coefficient = -0.90). Among mothers with mental health issues, having a child with a health issue was associated with increased willingness to enroll in research, compared with having children without health issues (estimated difference = 0.65).

Negative association of perceived risk and willingness to participate in innovative psychiatric research protocols

Psychiatric researchers grapple with concerns that individuals with mental illness may be less likely to appreciate risks of research participation, particularly compared to people not suffering from mental illness. Therefore, empirical studies that directly compare the perspectives of such individuals are needed. In addition, it is important to evaluate perspectives regarding varied types of research protocols, particularly as innovative psychiatric research protocols emerge. In this pilot study, respondents with a mood disorder (n = 25) as well as respondents without a mood disorder (n = 55) were recruited using Amazon's Mechanical Turk (MTurk) platform. These respondents were surveyed regarding four psychiatric research projects (i.e., experimental medication [pill form]; non-invasive magnetic brain stimulation; experimental medication [intravenous infusion]; and implantation of a device in the brain). Regardless of health status, respondents rated the four research protocols as somewhat to highly risky. The brain-device implant protocol was seen as the most risky, while the magnetic brain stimulation project was viewed as "somewhat risky". Respondents, on average and regardless of health status, rated their willingness at or below "somewhat willing." Respondents were least willing to participate in the brain-device implant protocol, whereas they were "somewhat willing" to participate in the magnetic brain stimulation protocol. Trust in medical research was negatively associated with perceived risk of research protocols. Perceived risk was negatively associated with willingness to participate, even when adjusting for potential confounders, suggesting that attunement to risk crosses diagnostic, gender, and ethnic categories, and is more salient to research decision-making than trust in medical research and dispositional optimism. The findings of this study may offer reassurance about the underlying decision-making processes of individuals considering participation in innovative neuroscience studies.

Comparing a Tailored Self-Help Mobile App With a Standard Self-Monitoring App for the Treatment of Eating Disorder Symptoms: Randomized Controlled Trial

BACKGROUND

Eating disorders severely impact psychological, physical, and social functioning, and yet, the majority of individuals with eating disorders do not receive treatment. Mobile health apps have the potential to decrease access barriers to care and reach individuals who have been underserved by traditional treatment modalities.

OBJECTIVE

The objective of this study was to evaluate the effectiveness of a tailored, fully automated self-help version of Recovery Record, an app developed for eating disorders management. We examined differences in eating disorder symptom change in app users that were randomized to receive either a standard, cognitive behavioral therapy-based version of the app or a tailored version that included algorithmically determined clinical content aligned with baseline and evolving user eating disorder symptom profiles.

METHODS

Participants were people with eating disorder symptoms who did not have access to traditional treatment options and were recruited via the open-access Recovery Record app to participate in this randomized controlled trial. We examined both continuous and categorical clinical improvement outcomes (measured with the self-report Eating Disorder Examination Questionnaire [EDE-Q]) in both intervention groups.

RESULTS

Between December 2016 and August 2018, 3294 Recovery Record app users were recruited into the study, out of which 959 were considered engaged, completed follow-up assessments, and were included in the analyses. Both study groups achieved significant overall outcome improvement, with 61.6% (180/292) of the tailored group and 55.4% (158/285) of the standard group achieving a clinically meaningful change in the EDE-Q, on average. There were no statistically significant differences between randomized groups for continuous outcomes, but a pattern of improvement being greater in the tailored group was evident. The rate of remission on the EDE-Q at 8 weeks was significantly greater in the group receiving the tailored version (d=0.22; P≤.001).

CONCLUSIONS

This is the first report to compare the relative efficacy of two versions of a mobile app for eating disorders. The data suggest that underserved individuals with eating disorder symptoms may benefit clinically from a self-help app and that personalizing app content to specific clinical presentations may be more effective in promoting symptomatic remission on the EDE-Q than content that offers a generic approach.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02503098; https://clinicaltrials.gov/ct2/show/NCT02503098.

Safeguarding Participants in Psychiatric Genetic Research: Perspectives of Key Stakeholder Groups

Public trust in research depends on implementation of research protections. Genetic and psychiatric research may elicit "exceptionalism," the belief that these types of research deserve special protections. Genetic information has been viewed as different from other health information. Psychiatric research has been scrutinized based on concerns about the impact of psychiatric illness on individuals' abilities to make decisions. This study compared four stakeholder groups' attitudes toward research safeguards. Psychiatric genetic researchers and institutional review board chairs received structured surveys. Individuals with mental illness and family members participated in semistructured interviews. Paired sample t-tests were used to compare mean ratings of importance of safeguard procedures for genetic versus nongenetic research on physical versus mental illnesses. All groups provided higher ratings for the importance of safeguards for genetic research and for mental illness. Individuals with mental illness and family members rated the importance of safeguards more highly than researchers and chairs did. Results of generalized linear models showed significant effects of gender and ethnicity.

Twelve-day medium pumping into tubular cell-laden scaffold using a lab-made PDMS connector

In the current study, a method is proposed to supply culture medium into a two-layered cell-laden tubular scaffold in order to enhance cell proliferation, confluence, and viability. The two-layered cell-laden tubular scaffold was made of calcium-alginate mixed with fibroblast cells (NIH/3T3) using a lab-made double- coaxial laminar-flow generator. Afterwards, the tubular scaffold was connected to a syringe pump system using a polydimethylsiloxane (PDMS) micro-connector for long-term cell culture. Three medium pumping conditions were applied and compared: a heart-beat-mimicking pumping (20 µL/s, 1 s period, and 50 % pulse width), a continuous pumping (20 µL/s) and a non-pumping. Non-leaky connections between the tubular scaffolds and the micro-connector outlet were sustained for 13.5 ± 0.83 d in heartbeat-mimicking pumping and 11.8 ± 0.33 d in continuous pumping condition, due to the elasticity of the tubular scaffolds. Importantly, the two pumping conditions resulted in more cell proliferation, confluence, and viability than the non-pumping condition. Furthermore, analysis of newly-produced type-I collagen matrix indicated that the cells under the two pumping conditions formed a tissue-like structure. The proposed technique could further be applied to vascular co-culturing for vascular engineered tissue.

Attitudes Regarding Enrollment in a Genetic Research Project: An Informed Consent Simulation Study Comparing Views of People With Depression, Diabetes, and Neither Condition

In this study, participants with a self-reported history of depression, diabetes, or no illness underwent a simulated informed consent process for a hypothetical genetic study related to depression or diabetes. Participants completed a survey assessing their perceived understanding of the research process, perceptions of its risks and benefits, their satisfaction with the informed consent process, and their readiness to make a hypothetical enrollment decision. All participants indicated strong readiness to make an enrollment decision regarding the research characterized in the simulation. Participants reported understanding the consent process relatively well and being generally satisfied with it. Greater concerns were expressed regarding psychosocial risks than biological risks for genetic studies on mental disorders. Our study documented positive attitudes toward volunteering for research that involved the collection of genetic data.

Perspectives of psychiatric investigators and IRB chairs regarding benefits of psychiatric genetics research

There is hope that psychiatric genetics inquiry will provide important insights into the origins and treatment of mental illness given the burden of these conditions. We sought to examine perspectives of psychiatric genetic investigators regarding the potential benefits of genetic research in general and the potential benefits of genetic research for the diagnosis and treatment of mental illnesses specifically. We compared investigator attitudes with those of chairs of Institutional Review Boards (IRBs) entrusted with evaluating the benefits and risks of human research studies. Two groups directly engaged with the conduct and oversight of psychiatric genetic research were examined (psychiatric investigators, n = 203; IRB Chairs, n = 183). Participants rated 15 survey items regarding current and future benefits of general genetic research, possible benefits of psychiatric genetic research, and the importance to society of genetic vs. non-genetic research examining causes and treatments of illnesses. Investigators and IRB Chairs strongly endorsed the future benefits of general genetic research for society and for the health of individuals; compared to IRB Chairs, investigators were more positive about these benefits. Even after adjusting for demographic variables, psychiatric genetic investigators were significantly more optimistic about genetic research compared with IRB Chairs. Both groups were moderately optimistic about the possible benefits of genetic research related to mental illness. Greater optimism was seen regarding new or personalized medications for mental illnesses, as well as genetic predictive testing of mental illnesses. Greater precision and circumspection about the potential benefits of psychiatric genetic research are needed.

Views of the importance of psychiatric genetic research by potential volunteers from stakeholder groups

Few studies have explored potential volunteers' attitudes toward genetic research. To address this gap in the literature, we developed an empirical project to document views held by individuals who may wish to enroll in genetic studies involving mental disorders. People living with mental illness, family members of people with mental illness, and community comparison volunteers were queried regarding their views on the importance of genetic research generally, in comparison with medical research, and in relation to 12 health conditions categorized in four types. T-tests and univariate and multivariate analysis of variance were used as appropriate. Participants expressed support for the importance of genetic research (mean = 9.43, scale = 1-10) and endorsed genetic research more highly compared with non-genetic medical research (mean = 9.43 vs. 8.69, P value = <0.001). The most highly endorsed genetic research was for cognitive disorders, followed by mental illness disorders, physical illness disorders, and addiction disorders (means = 8.88, 8.26, 8.16 and 7.55, respectively, P value = <0.001). Overall, this study provides evidence of strong endorsement of genetic research over non-genetic research by potential volunteers.

The Utility and Acceptability of a Self-Help Smartphone Application for Eating Disorder Behaviors

OBJECTIVE

Smartphone applications (apps) for eating disorders are a promising approach to assist individuals who do not receive traditional treatment. This study examines usage characteristics, perceptions regarding the acceptability of a new self-help intervention developed for users with eating disorders, and associations between attitudes and use patterns.

METHODS

189 individuals pilot-tested a personalized app-based program, and 133 completed the required components of the pilot-test over an 8-day period. Of these, 64 individuals (49%) completed an exit survey pertaining to acceptability.

RESULTS

Seventy percent of those who pilot-tested the app-based program completed the required components, i.e. a baseline review and then a 1-week assessment. Body mass index was associated with the total number of recorded meal logs. Study participants rated the app as highly suitable and acceptable, providing evidence of the feasibility and appropriateness of the program.

CONCLUSION

The app-based program demonstrated feasibility of deploying the app across user groups and high acceptability.

Does informed consent given by healthy individuals when enrolling in clinical research feel less voluntary than for ill individuals?

Clinical research is predicated ethically on the authentic voluntarism of individuals who choose to enroll in human studies. Existing literature has focused on aspects of informed consent for clinical research other than voluntarism. The objective of this study was to compare the perspectives of clinical research participants who are in good health and who are ill regarding voluntarism-related aspects of informed consent and to assess situational influences that enable voluntarism in the process of obtaining clinical research consent. A 23-item written survey, the Informed Consent Questionnaire (ICQ), was administered in a "piggyback" semi-structured interview study of ill and healthy volunteers enrolled in IRB-approved clinical research studies. A total of 150 (60 mentally ill, 43 physically ill, and 47 healthy) clinical research participants participated. Respondents expressed positive views of their experiences with the informed consent processes for their respective clinical research protocols and respondents strongly endorsed items related to voluntarism irrespective of their illness type (range of means = [3.9, 4.8]). Ill participants more highly endorsed items relating to informed consent conditions (mentally ill vs healthy: 0.54 on a 5-point scale, P value = 0.01) (physically ill vs. healthy: 0.47 on a 5-point scale, P value = 0.01). The favorable views of clinical research participants regarding their experience of giving informed consent to enroll in a study were not surprising. Contrary to our a priori hypothesis, healthy individuals did not feel as positively as their ill counterparts.

C3d-binding Donor-specific HLA Antibody Is Associated With a High Risk of Antibody-mediated Rejection and Graft Loss in Stable Kidney Transplant Recipients: A Single-center Cohort Study

BACKGROUND

One risk factor for antibody-mediated rejection (ABMR) and poor outcome after kidney transplantation is donor-specific anti‒human leukocyte antigen (anti-HLA) antibodies (DSAs). In this study we sought to determine whether the presence of DSAs that bind complement component C3d could better predict ABMR and graft loss in stable kidney transplant recipients (KTRs).

METHODS

We included 220 stable KTRs in this study and screened them for DSAs from July 2013 to July 2016.

RESULTS

Of the 220 KTRs, DSAs were detected in 24 (10.9%). The incidence of ABMR was 3.6% (8 of 220) overall, and C3d-DSA‒positive KTRs had a significantly higher incidence than SA-DSA‒positive KTRs (63.3% vs 38.9%, P = .03). Most C3d-binding DSAs were anti-HLA class II antibodies (11 of 13, 84.6%). Class II C3d-binding DSA was also significantly associated with graft failure on multivariate analysis, as were ABMR, chronic ABMR, and high serum creatinine. Class II C3d-binding DSA was also significantly associated with lower graft survival after ABMR.

CONCLUSION

C3d-binding DSA, especially class II, was significantly associated with the risk of ABMR and graft loss in stable KTRs. We suggest that monitoring of stable KTRs for C3d-binding DSA, followed by biopsy, could aid in early recognition of ABMR and prevention of graft loss.

Subgrouping the users of a specialized app for eating disorders

Although mobile technologies for eating disorders (EDs) are burgeoning, there is limited data about the clinical characteristics of individuals using specialized smartphone applications (apps) without accompanying traditional forms of treatment. This study evaluated whether the users of an ED app cluster in clinically meaningful groups. Participants were 1,280 app users (91.3% female; mean age 27) who reported not being in a weekly treatment for their ED. A hierarchical cluster analysis distinguished five groups of participants, all approximating DSM-5 ED categories. One cluster comprised of non-female, ethnically diverse users with Bulimia Nervosa features. Findings suggest that app users resemble known patient classifications.

Receptiveness to participation in genetic research: A pilot study comparing views of people with depression, diabetes, or no illness

BACKGROUND

Genetic research in human health relies on the participation of individuals with or at-risk for different types of diseases, including health conditions that may be stigmatized, such as mental illnesses. This preliminary study examines the differences in attitudes toward participation in genetic research among individuals with a psychiatric disorder, individuals with a physical disorder, and individuals with no known illness.

METHODS

Seventy-nine individuals with a history of diabetes or depression, or no known illness, underwent a simulated consent process for a hypothetical genetic research study. They were then surveyed about their willingness to participate in the hypothetical study and their attitudes about future and family participation in genetic research.

RESULTS

Participants with and without a history of depression ranked participating in genetic and medical research as very important and indicated that they were likely to participate in the hypothetical genetics study. Expressed willingness to participate was generally stable and consistent with future willingness. Individuals less strongly endorsed willingness to ask family members to participate in genetic research.

CONCLUSION

Individuals with and without a history of mental illness viewed genetic and medical research favorably and expressed willingness to participate in real-time and in the future. Informed consent processes ideally include an exploration of influences upon volunteers' enrollment decisions. Additional empirical study of influences upon genetic research participation is important to ensure that volunteers' rights are respected and that conditions that greatly affect the health of the public are not neglected scientifically.

Is a short arm cast appropriate for stable distal radius fractures in patients older than 55 years? A randomized prospective multicentre study

We conducted a prospective randomized, multicentre study to compare short arm and long arm plaster casts for the treatment of stable distal radius fracture in patients older than 55 years. We randomly assigned patients over the age of 55 years who had stable distal radius fracture to either a short arm or long arm plaster cast at the first review 1 week after their injury. Radiographic and clinical follow-up was conducted at 1, 3, 5, 12 and 24 weeks following their injury. Also, degree of disability caused by each cast immobilization was evaluated at the patient's visit to remove the cast. There were no significant differences in radiological parameters between the groups except for volar tilt. Despite these differences in volar tilt, neither functional status as measured by the Disabilities of the Arm, Shoulder and Hand, nor visual analogue scale was significantly different between the groups. However, the mean score of disability caused by plaster cast immobilization and the incidence rate of shoulder pain were significantly higher in patients who had a long plaster cast. Our findings suggest that a short arm cast is as effective as a long arm cast for stable distal radius fractures in the elderly. Furthermore, it is more comfortable and introduces less restriction on daily activities.

LEVEL OF EVIDENCE

II.

Healthy individuals' perspectives on clinical research protocols and influences on enrollment decisions

BACKGROUND

Understanding the perspectives of healthy individuals is important ethically and for the advancement of science. We assessed perceptions of risk associated with research procedures, comparing views of healthy individuals with and without experience in clinical research, and the respondents' reported willingness to volunteer.

METHODS

Semistructured interviews and written surveys were conducted. Study participants were healthy individuals, half of whom were currently enrolled in clinical research and half of whom had no prior experience in clinical research. Participants were queried regarding seven "minimal risk" or "greater than minimal risk" protocol vignettes with procedures of three types: routine diagnostic tests, more burdensome (i.e., more effort or potential harm) diagnostic tests, and pharmacologic interventions. Views of influences on enrollment decisions were also assessed.

RESULTS

Most healthy individuals indicated that protocols with more burdensome or pharmacologic interventions were very risky (59%, 58%), as opposed to routine diagnostic test procedures (32%). Respondents' willingness to enroll in protocols varied by type of protocol (p value < .001) and was inversely correlated with risk assessments (regression coefficients from GEE = -0.4; -0.5; -0.7). The odds of healthy individuals with research experience expressing strong willingness to enroll in the depicted protocols were twice the odds of healthy individuals without research experience expressing the same level of willingness (OR = 2.0 95% CI: [1.1, 3.9]). Respondents did not assign risk categories as institutional review boards (IRBs) would, as indicated by low agreement (26%) between respondent and expert opinion on minimal risk protocols.

CONCLUSIONS

Perceptions of procedure risk appear to influence healthy individuals' willingness to enroll in protocols. Participants with experience in clinical research were far more likely to express willingness to enroll, a finding with important scientific and ethical implications. The lack of alignment between healthy individuals' views of protocol risk and IRB categorization warrants further study.

Perceptions of the Professional Development Value of Honorary Fellowship Award Experiences

OBJECTIVE

Professional societies engage in activities with the aim of nurturing highly talented early career members of their field. Little is known about the value of honorary fellowship awards given annually by professional societies. Following up on the only known prior study of this topic, authors queried fellowship awardees in one psychiatric society to better understand the perceived value of honorary fellowships and other outcomes, such as subsequent involvement in professional societies.

METHODS

The authors queried former participants in the Laughlin and Psychiatry Resident-In-Training Examination® (PRITE®) Programs regarding their fellowship experiences and their subsequent involvement in The American College of Psychiatrists and other psychiatry membership organizations. The authors obtained frequency data and analyzed responses using t-tests and chi-squared tests. Associations between the outcomes and demographic characteristics such as age, gender, and fellowship type was tested.

RESULTS

Responses were gathered from 143 individuals who had participated in the Laughlin Fellowship and 22 in the PRITE Fellowship. Respondents felt that that the fellowship experience had been helpful professionally. Laughlin fellows were older and more likely to have assumed a leadership role in professional organizations (60 % vs 36 %, p = 0.04). Laughlin fellows also more strongly endorsed professional recognition as a benefit at the time of receiving their award. Survey respondents reported increased participation in professional organizations and assumed leadership roles in The College and other professional organizations subsequent to the fellowship experience.

CONCLUSIONS

On the whole, fellows were generally positive about their experiences. Many respondents became involved with The College subsequent to their fellowship, but a larger proportion became involved with other organizations, including in leadership roles. Professional societies with early career programs such as the Laughlin Fellowship and the PRITE Fellowship appear to identify and support future leaders as intended, but these leaders may engage more with other professional societies.

Are individuals living with mental illness and their preferred alternative decision-makers attuned and aligned in their attitudes regarding treatment decisions?

BACKGROUND

Mental disorders account for considerable suffering and societal burden. Prospective alternative decision-makers may be engaged in helping make treatment decisions for those who live with serious mental disorders. Little is known about the ways in which alternative decision makers arrive at treatment recommendations and whether the perspectives of alternative decision makers and ill individuals are aligned.

METHODS

The authors queried community-dwelling individuals diagnosed with schizophrenia, anxiety, or mood disorders and their preferred alternative decision-makers on issues regarding treatment decisions and underlying ethically-salient perspectives using a written survey instrument. Complete data were obtained on 26 pairs (n = 52, total). Outcomes included perspectives on clinical decision-making and underlying values that may shape their life choices. Two-sided paired t-tests and graphical representations were used.

RESULTS

We found that preferred alternative decision-makers overall accurately predicted the views of ill individuals with respect to the role of the individual and of family in treatment decision making. Preferred alternative decision-makers slightly overestimated autonomy-related perspectives. The personal views of ill individuals and preferred alternative decision-makers were aligned with respect to different physical and mental disorders, except in relation to alcohol and substance use where alternative decision-makers placed greater emphasis on autonomy. Alignment was also discovered on underlying life values, except the role of spirituality which was greater among alternative decision-makers.

CONCLUSION

Preferred alternative decision-makers are an ethical safeguard to ensure the wellbeing and rights of seriously ill individuals. In this pilot study, preferred alternative decision makers were aligned with their ill family members concerning treatment-related decisions and underlying life values. Future research should continue to explore and clarify the views of ill individuals and alternative decision makers to determine the quality of this safeguard used in clinical settings.

Accelerated failure time model under general biased sampling scheme

Right-censored time-to-event data are sometimes observed from a (sub)cohort of patients whose survival times can be subject to outcome-dependent sampling schemes. In this paper, we propose a unified estimation method for semiparametric accelerated failure time models under general biased estimating schemes. The proposed estimator of the regression covariates is developed upon a bias-offsetting weighting scheme and is proved to be consistent and asymptotically normally distributed. Large sample properties for the estimator are also derived. Using rank-based monotone estimating functions for the regression parameters, we find that the estimating equations can be easily solved via convex optimization. The methods are confirmed through simulations and illustrated by application to real datasets on various sampling schemes including length-bias sampling, the case-cohort design and its variants.

Self-Assembled Silica Nanostructures: Simultaneous Discrimination of Handedness, Pitch and Diameter of Helical Silica Nanotubes

The left- and right-handed helical silica nanostructures were obtained with the aid of organic templates, the formation of the nanostructures might follow a co-operation self-assembly mechanism. The chirality of the organogel self-assemblies was successfully transcribed in to the silica. The helical pitch and pore size of the silica nanotubes sensitively depended on the optical purity of the neutral gelator in the reaction mixtures.

Attunement and alignment of people with schizophrenia and their preferred alternative decision-makers: An exploratory pilot study comparing treatment and research decisions

BACKGROUND

Schizophrenia is a serious mental disorder that may affect the decisional capacity, and as a consequence, preferred alternative decision-makers may be engaged to help with clinical care and research-related choices. Ideally, alternative decision-makers will seek to make decisions that fit with the views and preferences of the ill individual. Few data exist, however, comparing the views of alternative decision-makers to those of individuals with schizophrenia.

METHODS

We conducted a written survey with individuals with schizophrenia living in a community setting, and a parallel survey with the person whom the ill individual identified as being a preferred alternative decision-maker. Complete data were obtained on 20 pairs (n = 40, total). Domains queried included (a) burden, happiness, and safety of the ill individual and of his or her family in treatment and research decisions and (b) importance of ethical principles in every day life. Two-sided paired t-tests and graphical summaries were used to compare responses.

RESULTS

Individuals with schizophrenia and their linked preferred alternative decision-makers were attuned on four of six aspects of treatment decision-making and on all six aspects of research decision-making that we queried.

CONCLUSION

The preferred alternative decision-makers overall demonstrated attunement to the views of the ill individuals in this small study. Ill individuals and their preferred alternative decision-makers were aligned in their views of ethically-salient aspects of every day life. These novel findings suggest that alternative decision-makers identified by ill individuals may be able to guide choices based on an accurate understanding of the ill individuals' views and values.

Demonstrating Patterns in the Views Of Stakeholders Regarding Ethically-Salient Issues in Clinical Research: A Novel Use of Graphical Models in Empirical Ethics Inquiry

BACKGROUND

Empirical ethics inquiry works from the notion that stakeholder perspectives are necessary for gauging the ethical acceptability of human studies and assuring that research aligns with societal expectations. Although common, studies involving different populations often entail comparisons of trends that problematize the interpretation of results. Using graphical model selection - a technique aimed at transcending limitations of conventional methods - this report presents data on the ethics of clinical research with two objectives: (1) to display the patterns of views held by ill and healthy individuals in clinical research as a test of the study's original hypothesis and (2) to introduce graphical model selection as a key analytic tool for ethics research.

METHODS

In this IRB-approved, NIH-funded project, data were collected from 60 mentally ill and 43 physically ill clinical research protocol volunteers, 47 healthy protocol-consented participants, and 29 healthy individuals without research protocol experience. Respondents were queried on the ethical acceptability of research involving people with mental and physical illness (i.e., cancer, HIV, depression, schizophrenia, and post-traumatic stress disorder) and non-illness related sources of vulnerability (e.g., age, class, gender, ethnicity). Using a statistical algorithm, we selected graphical models to display interrelationships among responses to questions.

RESULTS

Both mentally and physically ill protocol volunteers revealed a high degree of connectivity among ethically-salient perspectives. Healthy participants, irrespective of research protocol experience, revealed patterns of views that were not highly connected.

CONCLUSION

Between ill and healthy protocol participants, the pattern of views is vastly different. Experience with illness was tied to dense connectivity, whereas healthy individuals expressed views with sparse connections. In offering a nuanced perspective on the interrelation of ethically relevant responses, graphical model selection has the potential to bring new insights to the field of ethics.

Informal health care practices of residents: "curbside" consultation and self-diagnosis and treatment

OBJECTIVE

The authors explore the experiences of residents with respect to informal care related to personal health, including "curbside consultation," self-diagnosis, and self-prescription-self-care practices that run counter to ethical guidelines in medicine.

METHODS

Residents at one medical school completed a written survey regarding their personal health care practices, including their experiences in seeking or providing informal consultation, self-diagnosis, and self-prescribing. The authors obtained frequency data and analyzed responses via cross-tabulation. They used logistic regression models to assess the association of reported informal care practices and potential confounders, such as age, gender, and training program.

RESULTS

One hundred and fifty-five residents volunteered (71 % response rate). Most respondents had sought health care formally (70 %), and more had sought informal care in the previous 12 months (80 %). Of those who had pursued informal care, 90 % endorsed having requested a physical exam, a laboratory test, or a medication prescription from an attending, resident, or medical student. Respondents (28 %) commonly endorsed prescribing medication for themselves. Most respondents (90 %) reported being approached for informal care at least once in the previous year, including 84 % who were approached for prescriptions and 22 % who were approached by attending physicians. Main reasons endorsed for informal care seeking related to busy schedules and to cost and confidentiality advantages. Psychiatry residents reported using both formal and informal channels for personal health care, and 31 % acknowledged prescribing medications for themselves.

CONCLUSIONS

Informal care was a common practice among the residents in this study. Residents reported time constraints as the greatest influence on informal care seeking, rather than reasons found in previous studies related to cost and quality of care, protection of confidentiality, or prevention of embarrassment. The effects of informal care practices involving resident physicians warrant additional study.

Giving voice to study volunteers: comparing views of mentally ill, physically ill, and healthy protocol participants on ethical aspects of clinical research

MOTIVATION

Ethical controversy surrounds clinical research involving seriously ill participants. While many stakeholders have opinions, the extent to which protocol volunteers themselves see human research as ethically acceptable has not been documented. To address this gap of knowledge, authors sought to assess views of healthy and ill clinical research volunteers regarding the ethical acceptability of human studies involving individuals who are ill or are potentially vulnerable.

METHODS

Surveys and semi-structured interviews were used to query clinical research protocol participants and a comparison group of healthy individuals. A total of 179 respondents participated in this study: 150 in protocols (60 mentally ill, 43 physically ill, and 47 healthy clinical research protocol participants) and 29 healthy individuals not enrolled in protocols. Main outcome measures included responses regarding ethical acceptability of clinical research when it presents significant burdens and risks, involves people with serious mental and physical illness, or enrolls people with other potential vulnerabilities in the research situation.

RESULTS

Respondents expressed decreasing levels of acceptance of participation in research that posed burdens of increasing severity. Participation in protocols with possibly life-threatening consequences was perceived as least acceptable (mean = 1.82, sd = 1.29). Research on serious illnesses, including HIV, cancer, schizophrenia, depression, and post-traumatic stress disorder, was seen as ethically acceptable across respondent groups (range of means = [4.0, 4.7]). Mentally ill volunteers expressed levels of ethical acceptability for physical illness research and mental illness research as acceptable and similar, while physically ill volunteers expressed greater ethical acceptability for physical illness research than for mental illness research. Mentally ill, physically ill, and healthy participants expressed neutral to favorable perspectives regarding the ethical acceptability of clinical research participation by potentially vulnerable subpopulations (difference in acceptability perceived by mentally ill - healthy = -0.04, CI [-0.46, 0.39]; physically ill - healthy = -0.13, CI [-0.62, -.36]).

CONCLUSIONS

Clinical research volunteers and healthy clinical research-"naïve" individuals view studies involving ill people as ethically acceptable, and their responses reflect concern regarding research that poses considerable burdens and risks and research involving vulnerable subpopulations. Physically ill research volunteers may be more willing to see burdensome and risky research as acceptable. Mentally ill research volunteers and healthy individuals expressed similar perspectives in this study, helping to dispel a misconception that those with mental illness should be presumed to hold disparate views.

Do investigators understand ethically-important perspectives of clinical research participants?: a 'piggy-back' study of attunement and alignment in serious illness research

OBJECTIVE

The authors sought to compare investigators' predictions of clinical research participants' attitudes regarding ethically-important considerations in serious illness research with attitudes expressed by participants ("attunement"), to compare the personal attitudes of investigators and clinical research participants ("alignment"), and to explore the association between views expressed and covariates.

METHOD

The authors queried clinical research participants with either physical or mental illness (n=100) and faculty investigators conducting the clinical research protocols in which these participants were enrolled (n=77). Outcomes included attitudes regarding importance of medical research, attributes of seriously ill people in the research situation, and influences on enrollment decisions by seriously ill people. Generalized estimating equations and linear regression models were used.

RESULTS

Investigators underestimated the importance of research about physical illness, mental illness, and healthy people to participants (βPI=0.59, 95% CI [0.36, 0.83]; βMI=0.60, 95% CI [0.27, 0.92]; βH=0.93, 95% CI [0.57, 1.29]). Investigators incorrectly predicted that participants would assess seriously ill people as more vulnerable in the research situation than participants did (β=-0.68, 95% CI [-1.11, -0.25]). Investigators and participants were aligned on the importance of illness research. Participants expressed greater agreement than investigators regarding the influences of ill individuals indicative of will and cognition in their enrollment decisions (β=0.69, 95% CI [0.25, 1.13]).

CONCLUSIONS

Investigators are attuned to and aligned with research participants in many, but not all, respects. Investigators may bring a protective bias in their predictions of the vulnerabilities of ill volunteers.

A Unified Approach to Semiparametric Transformation Models under General Biased Sampling Schemes

We propose a unified estimation method for semiparametric linear transformation models under general biased sampling schemes. The new estimator is obtained from a set of counting process-based unbiased estimating equations, developed through introducing a general weighting scheme that offsets the sampling bias. The usual asymptotic properties, including consistency and asymptotic normality, are established under suitable regularity conditions. A closed-form formula is derived for the limiting variance and the plug-in estimator is shown to be consistent. We demonstrate the unified approach through the special cases of left truncation, length-bias, the case-cohort design and variants thereof. Simulation studies and applications to real data sets are presented.

An ultra-low power (ULP) bandage-type ECG sensor for efficient cardiac disease management

This paper proposed an ultra-low power bandage-type ECG sensor (the size: 76 × 34 × 3 (mm(3)) and the power consumption: 1 mW) which allows for a continuous and real-time monitoring of a user's ECG signals over 24h during daily activities. For its compact size and lower power consumption, we designed the analog front-end, the SRP (Samsung Reconfigurable Processor) based DSP of 30 uW/MHz, and the ULP wireless RF of 1 nJ/bit. Also, to tackle motion artifacts(MA), a MA monitoring technique based on the HCP (Half-cell Potential) is proposed which resulted in the high correlation between the MA and the HCP, the correlation coefficient of 0.75 ± 0.18. To assess its feasibility and validity as a wearable health monitor, we performed the comparison of two ECG signals recorded form it and a conventional Holter device. As a result, the performance of the former is a little lower as compared with the latter, although showing no statistical significant difference (the quality of the signal: 94.3% vs 99.4%; the accuracy of arrhythmia detection: 93.7% vs 98.7%). With those results, it has been confirmed that it can be used as a wearable health monitor due to its comfortability, its long operation lifetime and the good quality of the measured ECG signal.

A note on Using regression models to analyze randomized trials: asymptotically valid hypothesis tests despite incorrectly specified models

In the context of randomized trials, Rosenblum and van der Laan (2009, Biometrics 63, 937-945) considered the null hypothesis of no treatment effect on the mean outcome within strata of baseline variables. They showed that hypothesis tests based on linear regression models and generalized linear regression models are guaranteed to have asymptotically correct Type I error regardless of the actual data generating distribution, assuming the treatment assignment is independent of covariates. We consider another important outcome in randomized trials, the time from randomization until failure, and the null hypothesis of no treatment effect on the survivor function conditional on a set of baseline variables. By a direct application of arguments in Rosenblum and van der Laan (2009), we show that hypothesis tests based on multiplicative hazards models with an exponential link, i.e., proportional hazards models, and multiplicative hazards models with linear link functions where the baseline hazard is parameterized, are asymptotically valid under model misspecification provided that the censoring distribution is independent of the treatment assignment given the covariates. In the case of the Cox model and linear link model with unspecified baseline hazard function, the arguments in Rosenblum and van der Laan (2009) cannot be applied to show the robustness of a misspecified model. Instead, we adopt an approach used in previous literature (Struthers and Kalbfleisch, 1986, Biometrika 73, 363-369) to show that hypothesis tests based on these models, including models with interaction terms, have correct type I error.

Validation of reported predialysis nephrology care of older patients initiating dialysis

The Centers for Medicare and Medicaid Services (CMS) Medical Evidence Report (form CMS-2728) queries providers about the timing of the patient's first nephrologist consultation before initiation of dialysis. The monitoring of disease-specific goals in the Healthy People 2020 initiative will use information from this question, but the accuracy of the reported information is unknown. We defined a cohort of 80,509 patients aged ≥67 years who initiated dialysis between July 2005 and December 2008 with ≥2 years of uninterrupted Medicare coverage as their primary payer. The primary referent, determined from claims data, was the first observed outpatient nephrologist consultation; secondary analyses used the earliest nephrology consultation, whether inpatient or outpatient. We used linear regression models to assess the associations among the magnitude of discrepant reporting and patient characteristics and we tested for any temporal trends. When using the earliest recorded outpatient nephrology encounter, agreement between the two sources of ascertainment was 48.2%, and the κ statistic was 0.29 when we categorized the timing of the visit into four periods (never, <6, 6-12, and >12 months). When we dichotomized the timing of first predialysis nephrology care at >12 or ≤12 months, accuracy was 70% (κ=0.36), but it differed by patient characteristics and declined over time. In conclusion, we found substantial disagreement between information from the CMS Medical Evidence Report and Medicare physician claims on the timing of first predialysis nephrologist care. More-specific instructions may improve reporting and increase the utility of form CMS-2728 for research and public health surveillance.

The effects of femoral graft placement on in vivo knee kinematics after anterior cruciate ligament reconstruction

Achieving anatomical graft placement remains a concern in Anterior Cruciate Ligament (ACL) reconstruction. The purpose of this study was to quantify the effect of femoral graft placement on the ability of ACL reconstruction to restore normal knee kinematics under in vivo loading conditions. Two different groups of patients were studied: one in which the femoral tunnel was placed near the anterior and proximal border of the ACL (anteroproximal group, n=12) and another where the femoral tunnel was placed near the center of the ACL (anatomic group, n=10) MR imaging and biplanar fluoroscopy were used to measure in vivo kinematics in these patients during a quasi-static lunge. Patients with anteroproximal graft placement had up to 3.4mm more anterior tibial translation, 1.1mm more medial tibial translation and 3.7° more internal tibial rotation compared to the contralateral side. Patients with anatomic graft placement had motion that more closely replicated that of the intact knee, with anterior tibial translation within 0.8mm, medial tibial translation within 0.5mm, and internal tibial rotation within 1°. Grafts placed anteroproximally on the femur likely provide insufficient restraint to these motions due to a more vertical orientation. Anatomical femoral placement of the graft is more likely to reproduce normal ACL orientation, resulting in a more stable knee. Therefore, achieving anatomical graft placement on the femur is crucial to restoring normal knee function and may decrease the rates of joint degeneration after ACL reconstruction.

An equatorial pacific ocean source of atmospheric mercury

Pronounced increases in total gaseous mercury (TGM) in the near surface marine atmosphere were found in the equatorial region (4 degrees N to 10 degrees S) of the Pacific Ocean at 160 degrees W. The atmospheric enhancement of TGM corresponded closely to sea-surface manifestations of equatorial upwelling as reflected in measured changes of temperature and nutrient concentrations as well as to variations of reactive mercury in surface seawater. The elevated atmospheric TGM levels most probably result from oceanic mercury evasion associated with upwelling and increased biological production that occurs in the equatorial Pacific Ocean.This evidence of sea-to-air mercury transfer supports model predictions of an oceanic source of atmospheric mercury and suggests that marine-derived mercury emissions should occur in other biologically productive regimes.

Comparison of particle size spectrum determination from images made using manual and automated image analysis

A digital processing method is described for determining the size spectra of sub-micron particles in natural water from transmission electron microscopy images of particles collected by ultracentrifugation, and is compared with traditional manual counting and size measurement methods. The processing method is based on the use of the MatLab Image Processing toolbox. The manual method was found to underestimate the population of particles smaller than 40 nm equivalent radius, primarily because of a "fatigue factor" in counting the very large numbers of particles in this size range. By contrast, the manual method produced higher particle counts of particles >50 nm radius, primarily because manual counters tend to group together particles as aggregates that digital processing indicates are not contiguous. The digitally-produced size spectrum for a river water sample was found to closely follow a power-series law down to the smallest particle size.

Endoscopic submucosal resection with double ligation technique for treatment of small rectal carcinoid tumors

BACKGROUND AND STUDY AIMS

It is difficult to achieve complete endoscopic resection of rectal carcinoid tumors without any procedure-related complications. In this study, we evaluated the efficacy and safety of endoscopic submucosal resection with double ligation (ESMR-DL) for the treatment of small rectal carcinoid tumors.

PATIENTS AND METHODS

Eleven rectal carcinoid tumors (in 11 patients) were resected by ESMR-DL between November 2001 and April 2004, using a conventional single-channel endoscope with an attached band-ligator device. The lesion was aspirated into the ligator device and an elastic band was placed around the base; a detachable snare was then used to ligate the stalk below the elastic band; and snare resection was performed above the elastic band. The resected specimens were examined with respect to size, histological atypia, depth of invasion, and the histological appearance of the resection margins.

RESULTS

All the lesions were excised completely without any complications. There was no tumor invasion beyond the submucosal layer and there was no evidence of atypia in any of the specimens. Tumor diameter varied from 2.0 mm to 10.0 mm (average 6.2 mm). None of the 11 specimens showed histopathological evidence of tumor involvement at the resection margins. There were no immediate or late complications (bleeding or perforation) after ESMR-DL. There was no local recurrence and there were no distant metastases in any patients during the mean follow-up period of 18 months.

CONCLUSION

Endoscopic submucosal resection with double ligation is a useful and safe method for the treatment of small rectal carcinoid tumors.

Effect of the Tube Diameter Distribution on the High-Temperature Structural Modification of Bundled Single-Walled Carbon Nanotubes

We present results of a systematic high-resolution transmission electron microscopy study of the thermal evolution of bundled single-walled carbon nanotubes (SWNTs) subjected to approximately 4-h high-temperature heat treatment (HTT) in a vacuum at successively higher temperatures up to 2200 degrees C. We have examined purified SWNT material derived from the HiPCO and ARC processes. These samples were found to thermally evolve along very different pathways that we propose depend on three factors: (1) initial diameter distribution, (2) concomitant tightness of the packing of the tubes in a bundle, and (3) the bundle size. Graphitic nanoribbons (GNR) were found to be the dominant high-temperature filament in ARC material after HTT = 2000 degrees C; they were not observed in any heat-treated HiPCO material. The first two major steps in the thermal evolution of HiPCO and ARC material agree with the literature, i.e., coalescence followed by the formation of multiwall carbon nanotubes (MWNTs). However, ARC material evolves to bundled MWNTs, while HiPCO evolves to isolated MWNTs. In ARC material, we find that the MWNTs collapse into multishell GNRs. The thermal evolution of these carbon systems is discussed in terms of the diameter distribution, nanotube coalescence pathways, C-C bond rearrangement, diffusion of carbon and subsequent island formation, as well as the nanotube collapse driven by van der Waals forces.

Thermal conversion of bundled carbon nanotubes into graphitic ribbons

High temperature heat treatment (HTT) of bundled single-walled carbon nanotubes (SWNTs) in vacuum ( approximately 10(-5) Torr) has been found to lead to the formation of two types of graphitic nanoribbons (GNRs), as observed by high-resolution transmission electron microscopy. Purified SWNT bundles were first found to follow two evolutionary steps, as reported previously, that is, tube coalescence (HTT approximately 1400 degrees C) and then massive bond rearrangement (HTT approximately 1600 degrees C), leading to the formation of bundled multiwall nanotubes (MWNTs) with 3-12 shells. At HTT > 1800 degrees C, we find that these MWNTs collapse into multishell GNRs. The first type of GNR we observed is driven by the collapse of diameter-doubled single-wall nanotubes, and their production is terminated at HTT approximately 1600 degrees C when the MWNTs also start to form. We propose that the collapse is driven by van der Waals forces between adjacent tubes in the same bundle. For HTT > 2000 degrees C, the heat-treated material is found to be almost completely in the multishell GNR form.

Developing products for personalized medicine: NIH Research Tools Policy applications

For innovators at academic or industrial institutions to develop personalized medicine products at the accelerated pace required, rapid access to state-of-the-art research tools and reagents are needed. Unreasonable restrictions or delays in the use of such tools may undermine the development of these customized diagnostics and therapeutic products designed to provide significant treatment benefits to patients who frequently do not benefit from traditional therapeutic approaches. In its funding agreements and its own internal research programs, the National Institutes of Health is implementing policies to facilitate the exchanges of these research tools and related resources.

Distribution and licensing of drug discovery tools--NIH perspectives

Now, more than ever, drug discovery conducted at industrial or academic facilities requires rapid access to state-of-the-art research tools. Unreasonable restrictions or delays in the distribution or use of such tools can stifle new discoveries, thus limiting the development of future biomedical products. In grants and its own research programs the National Institutes of Health (NIH) is implementing its new policy to facilitate the exchanges of these tools for research discoveries and product development.