Qualitative study of perceptions of factors contributing to success or failure among participants in a US weight loss trial of financial incentives and environmental change strategies

BACKGROUND

The use of financial incentives and environmental change strategies to encourage health behaviour change is increasingly prevalent. However, the experiences of participants in incentive interventions are not well characterised. Examination of participant perceptions of financial incentives and environmental strategies can offer insights about how these interventions are facilitating or failing to encourage behaviour change.

OBJECTIVE

This study aimed to learn how participants in a randomised trial that tested financial incentives and environmental interventions to support weight loss perceived factors contributing to their success or failure in the trial.

DESIGN

Qualitative study with one-time interviews of trial participants with high and low success in losing weight, supplemented by study records of incentive payments and weight loss.

PARTICIPANTS

24 trial participants (12 with substantial weight loss and 12 with no weight loss) stratified equally across the 4 trial arms (incentives, environmental strategies, combined and usual care) were interviewed.

ANALYTICAL APPROACH

Transcribed interviews were coded and interpreted using an iterative process. Explanation development was completed using an abductive approach.

RESULTS

Responses of trial participants who were very successful in losing weight differed in several ways from those who were not. Successful participants described more robust prior attempts at dietary and exercise modification, more active engagement with self-limitations, more substantial social support and a greater ability to routinise dietary and exercise changes than did participants who did not lose weight. Successful participants often stated that weight loss was its own reward, even without receiving incentives. Neither group could articulate the details of the incentive intervention or consistently differentiate incentives from study payments.

CONCLUSIONS

A number of factors distinguished successful from unsuccessful participants in this intervention. Participants who were successful tended to attribute their success to intrinsic motivation and prior experience. Making incentives more salient may make them more effective for participants with greater extrinsic motivation.

TRIAL REGISTRATION NUMBER

NCT02878343.

"The Equipoise Ruler:" A National Survey on Surgeon Judgment about the Value of Surgery

OBJECTIVE

The objective of this study was to understand professional norms regarding the value of surgery.

SUMMARY BACKGROUND DATA

Agreed-upon professional norms may improve surgical decision making by contextualizing the nature of surgical treatment for patients. However, the extent to which these norms exist among surgeons practicing in the US is not known.

METHODS

We administered a survey with 30 exemplar cases asking surgeons to use their best judgement to place each case on a scale ranging from "Definitely would do this surgery" to "Definitely would not do this surgery." We then asked surgeons to repeat their assessments after providing responses from the first survey. We interviewed respondents to characterize their rationale.

RESULTS

We received 580 responses, a response rate of 28.5%. For 19 of 30 cases there was consensus (≥60% agreement) about the value of surgery (range 63% - 99%). There was little within-case variation when the mode was for surgery and more variation when the mode was against surgery or equipoise. Exposure to peer response increased the number of cases with consensus. Women were more likely to endorse a non-operative approach when treatment had high mortality. Specialists were less likely to operate for salvage procedures. Surgeons noted their clinical practice was to withhold judgment and let patients decide despite their assessment.

CONCLUSIONS

Professional judgment about the value of surgery exists along a continuum. While there is less variation in judgment for cases that are highly beneficial, consensus can be improved by exposure to the assessments of peers.

Opportunities to improve opioid use disorder care for hospitalised patients with endocarditis

BACKGROUND

Driven by increased injection opioid use, rates of hospitalisation for infective endocarditis, an infection associated with injection drug use, are increasing. In the USA, 1 in 10 hospitalised patients for opioid use disorder-associated infective endocarditis (OUD-IE) die in the hospital and 1 in 20 have a patient-directed discharge. Emerging models of care reveal opportunities for healthcare systems to meet the complex care needs of these patients. We characterised promising practices of staff who care for these patients and identified areas for improvement.

METHODS

We conducted a qualitative study with 1-hour semistructured virtual interviews between October 2021 and March 2022. Participants included 26 healthcare staff who care for patients with OUD-IE at the Hospital of the University of Pennsylvania. We used thematic analysis of interviews guided by an abductive approach. Interviews were digitally recorded and transcribed and analysed using NVivo software.

RESULTS

Interviews were characterised by three major themes: (1) care rooted in interdisciplinary collaboration; (2) managing OUD and its sequelae in a setting not designed to treat OUD; and (3) clinician needs and barriers to change.

CONCLUSIONS

These findings highlight the facilitators of high-quality treatment for patients with OUD-IE, as well as the key areas for improvement. Findings add context to the complexity that both the healthcare staff and patients navigate during and following hospitalisation for OUD-IE. Needed changes include training staff to talk with patients about preparing for a return to drug use following hospitalisation, and changing discharge facilities' practices that hinder access for patients with OUD-IE.

Innovations in Surgical Communication 3-Promote Deliberation, Not Technical Education

This Viewpoint is the third of a 4-part series discussing ways to improve communication between surgeons and patients.

IS THERE A DIFFERENCE BETWEEN TERMINAL LUCIDITY AND PARADOXICAL LUCIDITY?

Recent arguments in aging and dementia research suggest that “terminal lucidity”—defined as unexpected communication or connectedness occurring shortly before death—is distinct from “paradoxical lucidity”—defined as an episode of communication or connectedness in a person who is assumed to have lost these capacities due to progressive neurodegeneration. We disagree with this distinction and argue that terminal lucidity is a special subtype of paradoxical lucidity. We suggest that specifying the relationship between terminal and paradoxical lucidity is important for investigating the underlying mechanism of lucidity in dementia.

Deciding with Others: Interdependent Decision-Making

Over the course of human life, health care decision-making is often interdependent. In this article, we use "interdependence" to refer to patients' engagement of nonclinicians-for example, family members or trusted friends-to reach health care decisions. Interdependence, we suggest, is common for patients in all stages of life, from early childhood to late adulthood. This view contrasts with the common bioethical assumption that medical decisions are either wholly independent or dependent and that independence or dependence is tightly coupled with a person's decision-making capacity. In this article, we array various approaches to decision-making along a continuum of interdependence. An appreciation of this continuum can empower patients and elucidate ethical challenges that arise when people transition between different kinds of interdependence across the life span.

What is paradoxical lucidity? The answer begins with its definition

Paradoxical lucidity in dementia is a clinically significant but understudied phenomenon. A provisional definition was proposed by the 2018 National Institute on Aging expert workshop and published in Alzheimer's and Dementia. However, several conceptual features of this definition remain vague, creating barriers to robust clinical research. Here, we critically analyze the provisional definition and present a refined definition that can be applied in clinical research. The refined definition is based on an analytic process our research group recently undertook to operationalize paradoxical lucidity for our own study protocol. Our goal is to facilitate debate and potentially harmonize interpretations of paradoxical lucidity among research groups.

Preliminary results from the COVID caregiving project

Background

Method

Results

Conclusion

Evaluating the Quality of Research Ethics Review and Oversight: A Systematic Analysis of Quality Assessment Instruments

BACKGROUND

Research ethics review committees (RERCs) and Human Research Protection Programs (HRPPs) are responsible for protecting the rights and welfare of research participants while avoiding unnecessary inhibition of valuable research. Evaluating RERC/HRPP quality is vital to determining whether they are achieving these goals effectively and efficiently, as well as what adjustments might be necessary. Various tools, standards, and accreditation mechanisms have been developed in the United States and internationally to measure and promote RERC/HRPP quality.

METHODS

We systematically reviewed 10 quality assessment instruments, examining their overall approaches, factors considered relevant to quality, how they compare to each other, and what they leave out. For each tool, we counted the number of times each of 34 topics (divided into structure, process, and outcome categories) was mentioned. We generated lists of which topics are most and least mentioned for each tool, which are most prevalent across tools, and which are left unmentioned. We also conducted content analysis for the 10 most common topics.

RESULTS

We found wide variability between instruments, common emphasis on process and structure with little attention to participant outcomes, and failure to identify clear priorities for assessment. The most frequently mentioned topics are Review Type, IRB Member Expertise, Training and Educational Resources, Protocol Maintenance, Record Keeping, and Mission, Approach, and Culture. Participant Outcomes is unmentioned in 8 tools; the remaining 2 tools include assessments based on adverse events, failures of informed consent, and consideration of participant experiences.

CONCLUSIONS

Our analysis confirms that RERC/HRPP quality assessment instruments largely rely on surrogate measures of participant protection. To prioritize between these measures and preserve limited resources for evaluating the most important criteria, we recommend that instruments focus on elements relevant to participant outcomes, robust board deliberation, and procedures most likely to address participant risks. Validation of these approaches remains an essential next step.

Moving beyond the theoretical: Medical students' desire for practical, role-specific ethics training

BACKGROUND

It has been widely reported that medical trainees experience situations with profound ethical implications during their clinical rotations. To address this, most U.S. medical schools include ethics curricula in their undergraduate programs. However, the contents of these curricula vary substantially. Our pilot study aimed to discover, from the students' perspective, how ethics pedagogy prepares medical students for clerkship and what gaps might remain.

METHODS

This qualitative study organized focus groups of third- and fourth-year medical students. Participants recounted ethical concerns encountered during clerkship rotations and reflected on how their medical school ethics curriculum informed their responses to these scenarios. Transcripts of the focus-group sessions were analyzed using a grounded theory approach to identify common themes that characterized the students' experiences.

RESULTS

While students' accounts demonstrated a solid grasp of ethical theory and attunement to ethical concerns presented in the clinic, they also consistently evinced an inability to act on these issues given clerks' particular position in a complex learning hierarchy. Students felt they received too little training in the role-specific application of medical ethics as clinical trainees. We found a desire among trainees for enhanced practical ethics training in preparation for the clerkship phase of medical education.

CONCLUSION

We recommend several strategies that can begin to address these findings. The use of roleplaying with standardized patients can enable students to practice engagement with ethical issues. Conventional ethics courses can focus more on action-based pedagogy and instruction in conflict management techniques. Finally, clear structures for reporting and seeking advice and support for addressing ethical issues can lessen students' apprehension about acting on ethical concerns.

Tidal changes on CT and progression of ARDS

Background

Uncertain prediction of outcome in acute respiratory distress syndrome (ARDS) impedes individual patient management and clinical trial design.

Objectives

To develop a radiological metric of injurious inflation derived from matched inspiratory and expiratory CT scans, calibrate it in a model of experimental lung injury, and test it in patients with ARDS.

Methods

73 anaesthetised rats (acid aspiration model) were ventilated (protective or non-protective) for up to 4 hours to generate a spectrum of lung injury. CT was performed (inspiratory and expiratory) at baseline each hour, paired inspiratory and expiratory images were superimposed and voxels tracked in sequential scans. In nine patients with ARDS, paired inspiratory and expiratory CT scans from the first intensive care unit week were analysed.

Results

In experimental studies, regions of lung with unstable inflation (ie, partial or reversible airspace filling reflecting local strain) were the areas in which subsequent progression of injury was greatest in terms of progressive infiltrates (R=0.77) and impaired compliance (R=0.67, p<0.01). In patients with ARDS, a threshold fraction of tissue with unstable inflation was apparent: >28% in all patients who died and ≤28% in all who survived, whereas segregation of survivors versus non-survivors was not possible based on oxygenation or lung mechanics.

Conclusions

A single set of superimposed inspiratory–expiratory CT scans may predict progression of lung injury and outcome in ARDS; if these preliminary results are validated, this could facilitate clinical trial recruitment and individualised care.

The use of hyperpolarized carbon-13 magnetic resonance for molecular imaging

Until recently, molecular imaging using magnetic resonance (MR) has been limited by the modality's low sensitivity, especially with non-proton nuclei. The advent of hyperpolarized (HP) MR overcomes this limitation by substantially enhancing the signal of certain biologically important probes through a process known as external nuclear polarization, enabling real-time assessment of tissue function and metabolism. The metabolic information obtained by HP MR imaging holds significant promise in the clinic, where it could play a critical role in disease diagnosis and therapeutic monitoring. This review will provide a comprehensive overview of the developments made in the field of hyperpolarized MR, including advancements in polarization techniques and delivery, probe development, pulse sequence optimization, characterization of healthy and diseased tissues, and the steps made towards clinical translation.

Abstract P6-09-10: All-cause survival estimates compared to observed survival in older women with breast cancer in CALGB 49907 and 369901 (Alliance A151503)

Background: Older adults represent 50% or more of all newly diagnosed cancer patients annually; these patients have multiple morbidities, complicating treatment decision-making.. Discussions about the risks and benefits of cancer treatments might be improved by having data on estimated all-cause survival. ePrognosis (http://eprognosis.ucsf.edu/carey2.php) is an online tool validated in older adults without cancer. We compared survival estimates using ePrognosis to observed survival in a population of women with early stage breast cancer who volunteered for cooperative group studies.

Methods: Participants in CALGB 49907 (n=194) and 369901 (n=809) who were age 70+ were included (total n=1003). Both studies had comparable eligibility: primary, newly diagnosed, invasive, non-metastatic breast cancer. In 49907, eligibly also included PS 0-2; in 369901 there were no PS restrictions, but women who failed a screening cognitive exam were excluded. The Carey 2-year Index from ePrognosis was used to estimate all-cause 2-year survival, based on age, sex, and daily function. Function (needing help from another person to bath and shop for groceries, difficulty walking several blocks and pushing or pulling a heavy object) was derived from the EORTC QLC-30. The Carey index from ePrognosis generates scores from 1-10, with higher scores indicating higher probability of death. Kaplan-Meier methods were used to obtain point estimates and confidence intervals for the observed 2-yr survival. A two sided z-test was used to test the hypothesis that the observed survival rate is equivalent to the predicted survival rate.

Results: At two years from study entry, 921 women were alive; 56 had died, and 26 were lost to follow-up/withdrawn. The population was, on average, 76 years old (SD 4.8), primarily white (89.3%), and the majority had hormone receptor positive tumors (79.4%). In our population, the Carey 2-years index predicated survival was not significantly different than observed rates in the 0-2 points and underestimated the survival rates for patients who had 3-6 points and 7-10 points.

ePrognosis Prediction49907 & 369901 PatientsPointsPredicted Probability of SurvivalNNumber of DeathsObserved Probability of Overall Survival at 2 years (%, 95% CI)p-value0-295%5332595% (93-97%)0.7433-688%4272394% (92-96%)&lt;0.0017-1064%43881% (65-90%)0.017

Conclusions: In this population of older women with breast cancer, using a few readily available data items, ePrognosis provided accurate survival estimates for women with a low probability of death (0-2 points) and underestimated all-cause survival in women with an increased probability of death (3-10 points). Further studies are needed to assess the validity of this tool in samples of cancer patients with higher risks of 2-year mortality. Extended follow-up to validate the tools in predicting 5- and 10-year all-cause and non-cancer mortality risk will further contribute to decision making in older patients.

Citation Format: Kimmick G, Pitcher B, Mandelblatt J, Clapp J, Ballman K, Barginear M, Freedman R, Artz A, Klepin H, Lafky J, Hopkins J, Winer E, Hudis C, Muss H, Cohen H, Jatoi A, Hurria A. All-cause survival estimates compared to observed survival in older women with breast cancer in CALGB 49907 and 369901 (Alliance A151503). [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P6-09-10.

Mild loss of lung aeration augments stretch in healthy lung regions

Inspiratory stretch by mechanical ventilation worsens lung injury. However, it is not clear whether and how the ventilator damages lungs in the absence of preexisting injury. We hypothesized that subtle loss of lung aeration during general anesthesia regionally augments ventilation and distension of ventilated air spaces. In eight supine anesthetized and intubated rats, hyperpolarized gas MRI was performed after a recruitment maneuver following 1 h of volume-controlled ventilation with zero positive end-expiratory pressure (ZEEP), FiO2 0.5, and tidal volume 10 ml/kg, and after a second recruitment maneuver. Regional fractional ventilation (FV), apparent diffusion coefficient (ADC) of (3)He (a measurement of ventilated peripheral air space dimensions), and gas volume were measured in lung quadrants of ventral and dorsal regions of the lungs. In six additional rats, computed tomography (CT) images were obtained at each time point. Ventilation with ZEEP decreased total lung gas volume and increased both FV and ADC in all studied regions. Increases in FV were more evident in the dorsal slices. In each lung quadrant, higher ADC was predicted by lower gas volume and by increased mean values (and heterogeneity) of FV distribution. CT scans documented 10% loss of whole-lung aeration and increased density in the dorsal lung, but no macroscopic atelectasis. Loss of pulmonary gas at ZEEP increased fractional ventilation and inspiratory dimensions of ventilated peripheral air spaces. Such regional changes could help explain a propensity for mechanical ventilation to contribute to lung injury in previously uninjured lungs.

Ascorbic acid prolongs the viability and stability of isolated perfused lungs: A mechanistic study using 31P and hyperpolarized 13C nuclear magnetic resonance

Ex vivo lung perfusion (EVLP) has recently shown promise as a means of more accurately gauging the health of lung grafts and improving graft performance post-transplant. However, reperfusion of ischemic lung promotes the depletion of high-energy compounds and a progressive loss of normal mitochondrial function, and it remains unclear how and to what extent the EVLP approach contributes to this metabolic decline. Although ascorbate has been used to mitigate the effects of ischemia-reperfusion injury, the nature of its effects during EVLP are also not clear. To address these uncertainties, this study monitored the energy status of lungs during EVLP and after the administration of ascorbate using (31)P and hyperpolarized (13)C NMR (nuclear magnetic resonance). Our experiments demonstrated that the oxidative phosphorylation capacity and pyruvate dehydrogenase flux of lungs decline during ex vivo perfusion. The addition of ascorbate to the perfusate prolonged lung viability by 80% and increased the hyperpolarized (13)C bicarbonate signal by a factor of 2.7. The effect of ascorbate is apparently due not to its antioxidant quality but rather to its ability to energize cellular respiration given that it increased the lung's energy charge significantly, whereas other antioxidants (glutathione and α-lipoic acid) did not alter energy metabolism. During ascorbate administration, inhibition of mitochondrial complex I with rotenone depressed energy charge and shifted the metabolic state of the lung toward glycolysis; reenergizing the electron transport chain with TMPD (N,N,N',N'-tetramethyl-p-phenylenediamine) recovered metabolic activity. This indicates that ascorbate slows the decline of the ex vivo perfused lung's mitochondrial activity through an independent interaction with the electron transport chain complexes.

Multibreath alveolar oxygen tension imaging

PURPOSE

This study tested the ability of a multibreath hyperpolarized HP (3) He MRI protocol to increase the accuracy of regional alveolar oxygen tension (PA O2 ) measurements by lessening the influence of gas-flow artifacts. Conventional single-breath PA O2 measurement has been susceptible to error induced by intervoxel gas flow, particularly when used to study subjects with moderate-to-severe chronic obstructive pulmonary disease (COPD).

METHODS

Both single-breath and multibreath PA O2 imaging schemes were implemented in seven human subjects (one healthy, three asymptomatic smokers, and three COPD). The number and location of voxels with nonphysiologic PA O2 values generated by intervoxel gas flow were compared between the two protocols.

RESULTS

The multibreath scheme resulted in a significantly lower total percentage of nonphysiologic PA O2 values (6.0%) than the single-breath scheme (13.7%) (P = 0.006). PA O2 maps showed several patterns of gas-flow artifacts that were present in the single-breath protocol but mitigated by the multibreath approach. Multibreath imaging also allowed for the analysis of slow-filling areas that presented no signal after a single breath.

CONCLUSION

A multibreath approach enhances the accuracy and completeness of noninvasive PA O2 measurement by significantly lessening the proportion of nonphysiologic values generated by intervoxel gas flow. Magn Reson Med 76:1092-1101, 2016. © 2015 Wiley Periodicals, Inc.

Low-temperature dynamic nuclear polarization of gases in Frozen mixtures

PURPOSE

To present a new cryogenic technique for preparing gaseous compounds in solid mixtures for polarization using dynamic nuclear polarization (DNP).

METHODS

(129) Xe and (15) N2 O samples were prepared using the presented method. Samples were hyperpolarized at 1.42K at 5 Tesla. (129) Xe was polarized at 1.65K and 1.42K to compare enhancement. Polarization levels for both samples and T1 relaxation times for the (129) Xe sample were measured. Sample pulverization for the (129) Xe and controlled annealing for both samples were introduced as additional steps in sample preparation.

RESULTS

Enhancement increased by 15% due to a temperature drop from 1.65K to 1.42K for the (129) Xe sample. A polarization level of 20 ± 3% for the (129) Xe sample was achieved, a two-fold increase from 10 ± 1% after pulverization of the sample at 1.42K. T1 of the (129) Xe sample was increased by more than three-fold by means of annealing. In the case of (15) N2 O, annealing led to a ∼two-fold increase in the signal level after DNP.

CONCLUSION

The presented technique for producing and manipulating solid gas/glassing agent/radical mixtures for DNP led to high polarization levels in (129) Xe and (15) N2 O samples. These methods show potential for polarizing other gases using DNP technology. Magn Reson Med 76:1007-1014, 2016. © 2015 Wiley Periodicals, Inc.

Hyperpolarized gas diffusion MRI for the study of atelectasis and acute respiratory distress syndrome

Considerable uncertainty remains about the best ventilator strategies for the mitigation of atelectasis and associated airspace stretch in patients with acute respiratory distress syndrome (ARDS). In addition to several immediate physiological effects, atelectasis increases the risk of ventilator-associated lung injury, which has been shown to significantly worsen ARDS outcomes. A number of lung imaging techniques have made substantial headway in clarifying the mechanisms of atelectasis. This paper reviews the contributions of computed tomography, positron emission tomography, and conventional MRI to understanding this phenomenon. In doing so, it also reveals several important shortcomings inherent to each of these approaches. Once these shortcomings have been made apparent, we describe how hyperpolarized (HP) gas MRI--a technique that is uniquely able to assess responses to mechanical ventilation and lung injury in peripheral airspaces--is poised to fill several of these knowledge gaps. The HP-MRI-derived apparent diffusion coefficient (ADC) quantifies the restriction of (3) He diffusion by peripheral airspaces, thereby obtaining pulmonary structural information at an extremely small scale. Lastly, this paper reports the results of a series of experiments that measured ADC in mechanically ventilated rats in order to investigate (i) the effect of atelectasis on ventilated airspaces, (ii) the relationship between positive end-expiratory pressure (PEEP), hysteresis, and the dimensions of peripheral airspaces, and (iii) the ability of PEEP and surfactant to reduce airspace dimensions after lung injury. An increase in ADC was found to be a marker of atelectasis-induced overdistension. With recruitment, higher airway pressures were shown to reduce stretch rather than worsen it. Moving forward, HP MRI has significant potential to shed further light on the atelectatic processes that occur during mechanical ventilation.

Semiautomatic segmentation of longitudinal computed tomography images in a rat model of lung injury by surfactant depletion

Quantitative analysis of computed tomography (CT) is essential to the study of acute lung injury. However, quantitative CT is made difficult by poor lung aeration, which complicates the critical step of image segmentation. To overcome this obstacle, this study sought to develop and validate a semiautomated, multilandmark, registration-based scheme for lung segmentation that is effective in conditions of poor aeration. Expiratory and inspiratory CT images were obtained in rats (n = 8) with surfactant depletion of incremental severity to mimic worsening aeration. Trained operators manually delineated the images to provide a comparative landmark. Semiautomatic segmentation originated from a single, previously segmented reference image obtained at healthy baseline. Deformable registration of the target images (after surfactant depletion) was performed using the symmetric diffeomorphic transformation model with B-spline regularization. Registration used multiple landmarks (i.e., rib cage, spine, and lung parenchyma) to minimize the effect of poor aeration. Then target images were automatically segmented by applying the calculated transformation function to the reference image contour. Semiautomatically and manually segmented contours proved to be highly similar in all aeration conditions, including those characterized by more severe surfactant depletion and expiration. The Dice similarity coefficient was over 0.9 in most conditions, confirming high agreement, irrespective of poor aeration. Furthermore, CT density-based measurements of gas volume, tissue mass, and lung aeration distribution were minimally affected by the method of segmentation. Moving forward, multilandmark registration has the potential to streamline quantitative CT analysis by enabling semiautomatic image segmentation of lungs with a broad range of injury severity.

Carbon deposition and phase transformations in red mud on exposure to methane

A characterization study detailing the phase transformations and microstructural nature of the carbon deposited during methane decomposition over red mud has been undertaken. In situ XRD was carried out to study the phase transformation sequences of red mud during the reaction. Scanning electron microscopy, high resolution transmission electron microscopy, thermogravimetric analysis, BET surface area determination and CHN analysis were carried out to investigate the properties of the post-reaction samples. Exposure to methane with increasing temperature caused a stepwise reduction of iron oxides in red mud and promoted methane cracking leading to carbon deposition. The presence of carbon nanostructures was confirmed by HRTEM observations. The carbon formed was graphitic in nature and the spent red mud, rich in Fe and Fe(3)C formed as a result of the reduction of the iron oxide, was magnetic in nature. The surface area of the material was enhanced upon reaction. In addition, reactivity comparisons between goethite and red mud were carried out to study the formation of carbon oxides during reaction.

Effect of drugs on progesterone metabolism in the female rat

Various drugs brought about a reduction of serum progesterone level irrespective of whether or not a potent inducer (phenobarbital, 4-methyl-coumarin) or a hepatotoxin (carbon tetrachloride, alpha-naphthylisothiocyanate, coumarin) has been administered. The decrease by hepatotoxins was highly significant during the estrus phase of the cycle. These treatments affected the hepatic level of progesterone and altered the uptake of [4-14C]progesterone in vivo. The serum level of progesterone was significantly decreased by phenobarbital and carbon tetrachloride; however, the incorporation into the liver was enhanced by phenobarbital and reduced by carbon tetrachloride. This opposing hepatic action showed selectivity; phenobarbital increased the oxidative pathway of progesterone metabolism (formation of 6 beta-, 16 alpha-, 20 alpha-hydroxyprogesterone) but the reductive pathway remained unaltered (formation of pregnanediol, pregnanolone). Conversely, carbon tetrachloride diminished oxidation and raised reduction of progesterone. These results have been confirmed by measurements of progesterone metabolism in vitro using isolated microsomes. Phenobarbital brought about an induction of progesterone 16 alpha-, 6 beta- and 20 alpha-hydroxylase, did not affect progesterone delta 4-5 alpha-dehydrogenase, whereas carbon tetrachloride inhibited hydroxylase and raised dehydrogenase activities. The action of these test compounds on serum and liver levels of progesterone and on the variation of progesterone metabolism seemed to be related to changes manifest in the function of the hepatic endoplasmic reticulum. Similar changes might be associated with the development of mild hepatic lesions induced by various steroids.

Inappropriate antidiuretic hormone secretion. Occurrence in a patient with Rocky Mountain spotted fever

A 51-year-old man with serologically confirmed Rocky Mountain spotted fever was believed to have inappropriate antidiuretic hormone (ADH) secretion. He was observed for four days in the hospital until the correct diagnosis was made. During this period, he progressively became more hyponatremic, despite a low BUN level and the administration of large amounts of sodium and water. At the time, his serum sodium concentration was 117 mEq/liter, and his urine was hypertonic to that of serum. Thereafter, his serum sodium level rose with fluid restriction. Rickettsia-induced CNS damage may have lead to the inappropriate ADH release that was observed in this patient.

Membranoproliferative glomerulonephritis. Progression from the pure form to the crescentic form with recurrence after transplantation

Described are the clinical course and renal morphologic findings in a patient with membranoproliferative glomerulonephritis. intially, the patient had a pure form of membranoproliferative glomerulonephritis but after a 3 year course, it became crescentic. After a renal allograft was performed, membranoproliferative glomerulonephritis recurred within 1 month in a pure form and subsequently developed into the crescentic form. This change occurred in the host kidney as well as in the allograft immediately after immunosuppressive and steroid therapy was discontinued.