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The mevalonate pathway produces essential lipid metabolites such as cholesterol. Although this pathway is negatively regulated by metabolic intermediates, little is known of the metabolites that positively regulate its activity. We found that the amino acid glutamine is required to activate the mevalonate pathway. Glutamine starvation inhibited cholesterol synthesis and blocked transcription of the mevalonate pathway-even in the presence of glutamine derivatives such as ammonia and α-ketoglutarate. We pinpointed this glutamine-dependent effect to a loss in the ER-to-Golgi trafficking of SCAP that licenses the activation of SREBP2, the major transcriptional regulator of cholesterol synthesis. Both enforced Golgi-to-ER retro-translocation and the expression of a nuclear SREBP2 rescued mevalonate pathway activity during glutamine starvation. In a cell model of impaired mitochondrial respiration in which glutamine uptake is enhanced, SREBP2 activation and cellular cholesterol were increased. Thus, the mevalonate pathway senses and is activated by glutamine at a previously uncharacterized step, and the modulation of glutamine synthesis may be a strategy to regulate cholesterol levels in pathophysiological conditions., (© 2024. The Author(s).)

Waste liquid mercury generated as a by-product of the Merrill-Crowe process in gold mining and recovered from mercury-containing waste must be stabilized for secure storage or disposal. This study developed a procedure for mercury stabilization. A ball mill with a 0.5 m 3 capacity and a rotational speed of 43 rpm was used to stabilize the residual mercury with sulfur. The treatments were conducted for 30, 60, and 90 min at mercury: sulfur molar ratios of 1.0, 0.8, and 0.67. The ball loading ratio was 7.0 with residual mercury, and the temperature was below 40 °C. The treatment efficiency was evaluated by measuring the concentrations of mercury and other metals using the Toxicity Characteristic Leaching Procedure (TCLP), examining the stabilized residual mercury by X-ray diffraction, and conducting bioassays on Daphnia magna and Lactuca sativa . Principal component analysis (PCA) was performed on the aforementioned variables. The 90-min treatment, with a mercury-to-sulfur molar ratio of 0.67, stabilized mercury mainly as cinnabar compared with the other treatments and presented leachate mercury values below the detection limit <0.003. The leachate from the treatments also showed values of 21.28-38.44 toxic units, classified as very toxic, and generated toxicity, particularly for D. magna , because of the presence of other metals such as Al, Ba, B, Ca, Cu, Cr, Fe, Mn, Ni, and Zn. The variability of the residues in the PCA analysis was explained by the treatment effect and the presence of other metals in the residual mercury. The stabilized residual mercury obtained was classified as non-hazardous and could be stored or disposed of as ordinary waste in a security landfill., Competing Interests: The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Pablo Neyra Avellaneda reports financial support was provided by National Innovation Program for Competitiveness and Productivity for Business Development Category 1, Innovate Peru of the Ministry of Production. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors.)

Extracellular chemical cues constitute much of the language of life among marine organisms, from microbes to mammals. Changes in this chemical pool serve as invisible signals of overall ecosystem health and disruption to this finely tuned equilibrium. In coral reefs, the scope and magnitude of the chemicals involved in maintaining reef equilibria are largely unknown. Processes involving small, polar molecules, which form the majority components of labile dissolved organic carbon, are often poorly captured using traditional techniques. We employed chemical derivatization with mass spectrometry-based targeted exometabolomics to quantify polar dissolved phase metabolites on five coral reefs in the U.S. Virgin Islands. We quantified 45 polar exometabolites, demonstrated their spatial variability, and contextualized these findings in terms of geographic and benthic cover differences. By comparing our results to previously published coral reef exometabolomes, we show the novel quantification of 23 metabolites, including central carbon metabolism compounds (e.g., glutamate) and novel metabolites such as homoserine betaine. We highlight the immense potential of chemical derivatization-based exometabolomics for quantifying labile chemical cues on coral reefs and measuring molecular level responses to environmental stressors. Overall, improving our understanding of the composition and dynamics of reef exometabolites is vital for effective ecosystem monitoring and management strategies.

Background: Predicting the need for invasive mechanical ventilation (IMV) is important for the allocation of human and technological resources, improvement of surveillance, and use of effective therapeutic measures. This study aimed (i) to assess whether the ABC 2 -SPH score is able to predict the receipt of IMV in COVID-19 patients; (ii) to compare its performance with other existing scores; (iii) to perform score recalibration, and to assess whether recalibration improved prediction., Methods: Retrospective observational cohort, which included adult laboratory-confirmed COVID-19 patients admitted in 32 hospitals, from 14 Brazilian cities. This study was conducted in two stages: (i) for the assessment of the ABC 2 -SPH score and comparison with other available scores, patients hospitalized from July 31, 2020, to March 31, 2022, were included; (ii) for ABC 2 -SPH score recalibration and also comparison with other existing scores, patients admitted from January 1, 2021, to March 31, 2022, were enrolled. For both steps, the area under the receiving operator characteristic score (AUROC) was calculated for all scores, while a calibration plot was assessed only for the ABC 2 -SPH score. Comparisons between ABC 2 -SPH and the other scores followed the Delong Test recommendations. Logistic recalibration methods were used to improve results and adapt to the studied sample., Results: Overall, 9,350 patients were included in the study, the median age was 58.5 (IQR 47.0-69.0) years old, and 45.4% were women. Of those, 33.5% were admitted to the ICU, 25.2% received IMV, and 17.8% died. The ABC 2 -SPH score showed a significantly greater discriminatory capacity, than the CURB-65, STSS, and SUM scores, with potentialized results when we consider only patients younger than 80 years old (AUROC 0.714 [95% CI 0.698-0.731]). Thus, after the ABC 2 -SPH score recalibration, we observed improvements in calibration (slope = 1.135, intercept = 0.242) and overall performance (Brier score = 0.127)., Conclusion: The ABC 2 -SPHr risk score demonstrated a good performance to predict the need for mechanical ventilation in COVID-19 hospitalized patients under 80 years of age., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Cimini, Delfino-Pereira, Pires, Ramos, Gomes, Jorge, Fagundes, Garcia, Pessoa, de Carvalho, Ponce, Rios, Anschau, Vigil, Bartolazzi, Grizende, Vietta, Goedert, Nascimento, Vianna, Vasconcelos, Alvarenga, Chatkin, Machado Rugolo, Ruschel, Zandoná, Menezes, Castro, Souza, Carneiro, Bicalho, Cunha, Sacioto, Lutkmeier, Oliveira, Andrade, Menezes, Ribeiro and Marcolino.)

Steroids are important membrane components and signaling metabolites and thus are required for cellular homeostasis. All mammalian cells retain the ability to uptake and synthesize steroids. Dysregulation of steroid levels leads to profound effects on cellular function and organismal health. Hence it comes as no surprise that steroid synthesis is tightly regulated. It is well established that the main site for steroid synthesis and regulation is the endoplasmic reticulum. However, mitochondria are essential for: (1) cholesterol production (the precursor of all steroids) by exporting citrate and; (2) the products of steroidogenesis (such as mineralocorticoids and glucocorticoids). In this review, we describe the midfield player role of mitochondria in steroid synthesis and bring the idea of mitochondria actively participating in steroid synthesis regulation. A better understanding of the mitochondrial regulatory roles in steroid synthesis would open new avenues to targeted approaches aiming to control steroid levels., Competing Interests: Declaration of Competing Interest The authors declare no conflict of interest., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Ion mobility (IM) spectrometry provides semiorthogonal data to mass spectrometry (MS), showing promise for identifying unknown metabolites in complex non-targeted metabolomics data sets. While current literature has showcased IM-MS for identifying unknowns under near ideal circumstances, less work has been conducted to evaluate the performance of this approach in metabolomics studies involving highly complex samples with difficult matrices. Here, we present a workflow incorporating de novo molecular formula annotation and MS/MS structure elucidation using SIRIUS 4 with experimental IM collision cross-section (CCS) measurements and machine learning CCS predictions to identify differential unknown metabolites in mutant strains of Caenorhabditis elegans . For many of those ion features, this workflow enabled the successful filtering of candidate structures generated by in silico MS/MS predictions, though in some cases, annotations were challenged by significant hurdles in instrumentation performance and data analysis. While for 37% of differential features we were able to successfully collect both MS/MS and CCS data, fewer than half of these features benefited from a reduction in the number of possible candidate structures using CCS filtering due to poor matching of the machine learning training sets, limited accuracy of experimental and predicted CCS values, and lack of candidate structures resulting from the MS/MS data. When using a CCS error cutoff of ±3%, on average, 28% of candidate structures could be successfully filtered. Herein, we identify and describe the bottlenecks and limitations associated with the identification of unknowns in non-targeted metabolomics using IM-MS to focus and provide insights into areas requiring further improvement.

Untargeted metabolomics studies are unbiased but identifying the same feature across studies is complicated by environmental variation, batch effects, and instrument variability. Ideally, several studies that assay the same set of metabolic features would be used to select recurring features to pursue for identification. Here, we developed an anchored experimental design. This generalizable approach enabled us to integrate three genetic studies consisting of 14 test strains of Caenorhabditis elegans prior to the compound identification process . An anchor strain, PD1074, was included in every sample collection, resulting in a large set of biological replicates of a genetically identical strain that anchored each study. This enables us to estimate treatment effects within each batch and apply straightforward meta-analytic approaches to combine treatment effects across batches without the need for estimation of batch effects and complex normalization strategies. We collected 104 test samples for three genetic studies across six batches to produce five analytical datasets from two complementary technologies commonly used in untargeted metabolomics. Here, we use the model system C. elegans to demonstrate that an augmented design combined with experimental blocks and other metabolomic QC approaches can be used to anchor studies and enable comparisons of stable spectral features across time without the need for compound identification. This approach is generalizable to systems where the same genotype can be assayed in multiple environments and provides biologically relevant features for downstream compound identification efforts. All methods are included in the newest release of the publicly available SECIMTools based on the open-source Galaxy platform., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Shaver, Garcia, Gouveia, Morse, Liu, Asef, Borges, Leach, Andersen, Amster, Fernández, Edison and McIntyre.)

Background: Acute kidney injury (AKI) is frequently associated with COVID-19, and the need for kidney replacement therapy (KRT) is considered an indicator of disease severity. This study aimed to develop a prognostic score for predicting the need for KRT in hospitalised COVID-19 patients, and to assess the incidence of AKI and KRT requirement., Methods: This study is part of a multicentre cohort, the Brazilian COVID-19 Registry. A total of 5212 adult COVID-19 patients were included between March/2020 and September/2020. Variable selection was performed using generalised additive models (GAM), and least absolute shrinkage and selection operator (LASSO) regression was used for score derivation. Accuracy was assessed using the area under the receiver operating characteristic curve (AUC-ROC)., Results: The median age of the model-derivation cohort was 59 (IQR 47-70) years, 54.5% were men, 34.3% required ICU admission, 20.9% evolved with AKI, 9.3% required KRT, and 15.1% died during hospitalisation. The temporal validation cohort had similar age, sex, ICU admission, AKI, required KRT distribution and in-hospital mortality. The geographic validation cohort had similar age and sex; however, this cohort had higher rates of ICU admission, AKI, need for KRT and in-hospital mortality. Four predictors of the need for KRT were identified using GAM: need for mechanical ventilation, male sex, higher creatinine at hospital presentation and diabetes. The MMCD score had excellent discrimination in derivation (AUROC 0.929, 95% CI 0.918-0.939) and validation (temporal AUROC 0.927, 95% CI 0.911-0.941; geographic AUROC 0.819, 95% CI 0.792-0.845) cohorts and good overall performance (Brier score: 0.057, 0.056 and 0.122, respectively). The score is implemented in a freely available online risk calculator ( https://www.mmcdscore.com/ )., Conclusions: The use of the MMCD score to predict the need for KRT may assist healthcare workers in identifying hospitalised COVID-19 patients who may require more intensive monitoring, and can be useful for resource allocation., (© 2022. The Author(s).)

The use of quality control samples in metabolomics ensures data quality, reproducibility, and comparability between studies, analytical platforms, and laboratories. Long-term, stable, and sustainable reference materials (RMs) are a critical component of the quality assurance/quality control (QA/QC) system; however, the limited selection of currently available matrix-matched RMs reduces their applicability for widespread use. To produce an RM in any context, for any matrix that is robust to changes over the course of time, we developed iterative batch averaging method (IBAT). To illustrate this method, we generated 11 independently grown Escherichia coli batches and made an RM over the course of 10 IBAT iterations. We measured the variance of these materials by nuclear magnetic resonance (NMR) and showed that IBAT produces a stable and sustainable RM over time. This E. coli RM was then used as a food source to produce a Caenorhabditis elegans RM for a metabolomics experiment. The metabolite extraction of this material, alongside 41 independently grown individual C. elegans samples of the same genotype, allowed us to estimate the proportion of sample variation in preanalytical steps. From the NMR data, we found that 40% of the metabolite variance is due to the metabolite extraction process and analysis and 60% is due to sample-to-sample variance. The availability of RMs in untargeted metabolomics is one of the predominant needs of the metabolomics community that reach beyond quality control practices. IBAT addresses this need by facilitating the production of biologically relevant RMs and increasing their widespread use.

Cellulitis is a common clinical diagnosis in the outpatient and inpatient setting; studies have demonstrated a surprisingly high misdiagnosis rate: nearly one-third of cases are other conditions (ie, pseudocellulitis). This high rate of misdiagnosis is thought to contribute to nearly $515 million in avoidable health care spending in the United States each year; leading to the delayed or missed diagnosis of pseudocellulitis and to delays in appropriate treatment. There is a broad differential diagnosis for pseudocellulitis, which includes inflammatory and noninflammatory conditions of the skin. Accurate diagnosis of the specific condition causing pseudocellulitis is crucial to management, which varies greatly., Competing Interests: Disclosure The authors have nothing to disclose., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Offspring born to obese and diabetic mothers are prone to metabolic diseases, a phenotype that has been linked to mitochondrial dysfunction and endoplasmic reticulum (ER) stress in oocytes. In addition, metabolic diseases impact the architecture and function of mitochondria-ER contact sites (MERCs), changes which associate with mitofusin 2 (MFN2) repression in muscle, liver and hypothalamic neurons. MFN2 is a potent modulator of mitochondrial metabolism and insulin signaling, with a key role in mitochondrial dynamics and tethering with the ER. Here, we investigated whether offspring born to mice with MFN2-deficient oocytes are prone to obesity and diabetes. Deletion of Mfn2 in oocytes resulted in a profound transcriptomic change, with evidence of impaired mitochondrial and ER function. Moreover, offspring born to females with oocyte-specific deletion of Mfn2 presented increased weight gain and glucose intolerance. This abnormal phenotype was linked to decreased insulinemia and defective insulin signaling, but not mitochondrial and ER defects in offspring liver and skeletal muscle. In conclusion, this study suggests a link between disrupted mitochondrial/ER function in oocytes and increased risk of metabolic diseases in the progeny. Future studies should determine whether MERC architecture and function are altered in oocytes from obese females, which might contribute toward transgenerational transmission of metabolic diseases., (© The Author(s) 2020. Published by Oxford University Press on behalf of European Society of Human Reproduction and Embryology. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

The brachial plexus is an intricate anatomic structure with an important function: providing innervation to the upper extremity, shoulder, and upper chest. Owing to its complex form and longitudinal course, the brachial plexus can be challenging to conceptualize in three dimensions, which complicates evaluations in standard orthogonal imaging planes. The components of the brachial plexus can be determined by using key anatomic landmarks. Applying this anatomic knowledge, a radiologist should then be able to identify pathologic appearances of the brachial plexus by using imaging modalities such as MRI, CT, and US. Brachial plexopathies can be divided into two broad categories that are based on disease origin: traumatic and nontraumatic. In the traumatic plexopathy group, there are distinct imaging findings and management methods for pre- versus postganglionic injuries. For nontraumatic plexopathies, having access to an accurate patient history is often crucial. Knowledge of the timing of radiation therapy is critical to diagnosing post-radiation therapy brachial plexopathy. In acute brachial neuritis, antecedent stressors occur within a specific time frame. Primary and secondary tumors of the brachial plexus are not uncommon, with the most common primary tumors being peripheral nerve sheath tumors. Direct extension and metastasis from primary malignancies such as breast and lung cancer can occur. Although diagnosing a brachial plexus anomaly is potentially perplexing, it can be straightforward if it is based on foundational knowledge of anatomy, imaging findings, and pathologic features. © RSNA, 2020.

Mitochondrial function, largely regulated by the dynamics of this organelle, is inextricably linked to the oocyte health. In comparison with most somatic cells, mitochondria in oocytes are smaller and rounder in appearance, suggesting limited fusion. The functional implications of this distinct morphology, and how changes in the mitochondrial shape translate to mitochondrial function in oogenesis is little understood. We, therefore, asked whether the pro-fusion proteins mitofusins 1 (MFN1) and 2 (MFN2) are required for the oocyte development. Here we show that oocyte-specific deletion of Mfn1, but not Mfn2, prevents the oocyte growth and ovulation due to a block in folliculogenesis. We pinpoint the loss of oocyte growth and ovulation to impaired PI3K-Akt signaling and disrupted oocyte-somatic cell communication. In support, the double loss of Mfn1 and Mfn2 partially rescues the impaired PI3K-Akt signaling and defects in oocyte development secondary to the single loss of Mfn1. Together, this work demonstrates that the mitochondrial function influences the cellular signaling during the oocyte development, and highlights the importance of distinct, nonredundant roles of MFN1 and MFN2 in oogenesis., (© 2020 Federation of American Societies for Experimental Biology.)

Purpose: To determine whether higher rates of medical errors were associated with positive screenings for depression or burnout among resident physicians., Method: The authors conducted a prospective cohort study from 2011 to 2013 in seven pediatric academic medical centers in the United States and Canada. Resident physicians were screened for burnout and depression using the Maslach Burnout Inventory-Human Services Survey (MBI-HSS) and Harvard Department of Psychiatry/National Depression Screening Day Scale (HANDS). A two-step surveillance methodology, involving a research nurse and two physician reviewers, was used to measure and categorize errors. Bivariate and mixed-effects regression models were used to evaluate the relationship between burnout, depression, and rates of harmful, nonharmful, and total errors., Results: A total of 388/537 (72%) resident physicians completed the MBI-HSS and HANDS surveys. Seventy-six (20%) and 178 (46%) resident physicians screened positive for depression and burnout, respectively. Screening positive for depression was associated with a 3.0-fold higher rate of harmful errors (incidence rate ratio = 2.99 [95% CI 1.40-6.36], P = .005). However, there was no statistically significant association between depression and total or nonharmful errors or between burnout and harmful, nonharmful, or total errors., Conclusions: Resident physicians with a positive depression screen were three times more likely than those who screened negative to make harmful errors. This association suggests resident physician mental health could be an important component of patient safety. If further research confirms resident physician depression increases the risk of harmful errors, it will become imperative to determine what interventions might mitigate this risk.

Oocyte mitochondria are increased in number, smaller, and rounder in appearance than mitochondria in somatic cells. Moreover, mitochondrial numbers and activity are narrowly tied with oocyte quality because of the key role of mitochondria to oocyte maturation. During oocyte maturation, mitochondria display great mobility and cluster at specific sites to meet the high energy demand. Conversely, oocyte mitochondria are not required during early oogenesis as coupling with granulosa cells is sufficient to support gamete's needs. In part, this might be explained by the importance of protecting mitochondria from oxidative damage that result in mutations in mitochondrial DNA (mtDNA). Considering mitochondria are transmitted exclusively by the mother, oocytes with mtDNA mutations may lead to diseases in offspring. Thus, to counterbalance mutation expansion, the oocyte has developed specific mechanisms to filter out deleterious mtDNA molecules. Herein, we discuss the role of mitochondria on oocyte developmental potential and recent evidence supporting a purifying filter against deleterious mtDNA mutations in oocytes.

Background: Depression and burnout are highly prevalent among residents, but little is known about modifiable personality variables, such as resilience and stress from uncertainty, that may predispose to these conditions. Residents are routinely faced with uncertainty when making medical decisions., Objective: To determine how stress from uncertainty is related to resilience among pediatric residents and whether these attributes are associated with depression and burnout., Methods: We surveyed 86 residents in pediatric residency programs from 4 urban freestanding children's hospitals in North America in 2015. Stress from uncertainty was measured with the use of the Physicians' Reaction to Uncertainty Scale, resilience with the use of the 14-item Resilience Scale, depression with the use of the Harvard National Depression Screening Scale; and burnout with the use of single-item measures of emotional exhaustion and depersonalization from the Maslach Burnout Inventory., Results: Fifty out of 86 residents responded to the survey (58.1%). Higher levels of stress from uncertainty correlated with lower resilience (r = -0.60; P < .001). Five residents (10%) met depression criteria and 15 residents (31%) met burnout criteria. Depressed residents had higher mean levels of stress due to uncertainty (51.6 ± 9.1 vs 38.7 ± 6.7; P < .001) and lower mean levels of resilience (56.6 ± 10.7 vs 85.4 ± 8.0; P < .001) compared with residents who were not depressed. Burned out residents also had higher mean levels of stress due to uncertainty (44.0 ± 8.5 vs 38.3 ± 7.1; P = .02) and lower mean levels of resilience (76.7 ± 14.8 vs 85.0 ± 9.77; P = .02) compared with residents who were not burned out., Conclusions: We found high levels of stress from uncertainty, and low levels of resilience were strongly correlated with depression and burnout. Efforts to enhance tolerance of uncertainty and resilience among residents may provide opportunities to mitigate resident depression and burnout., (Copyright © 2018 Academic Pediatric Association. Published by Elsevier Inc. All rights reserved.)

Mitochondria play a fundamental role during development of the female germline. They are fragmented, round, and small. Despite these characteristics suggesting that they are inactive, there is accumulating evidence that mitochondrial dysfunctions are a major cause of infertility and generation of aneuploidies in humans. In addition, mitochondria and their own genomes (mitochondrial DNA-mtDNA) may become damaged with time, which might be one reason why aging leads to infertility. As a result, mitochondria have been proposed as an important target for evaluating oocyte and embryo quality, and developing treatments for female infertility. On the other hand, mutations in mtDNA may cause mitochondrial dysfunctions, leading to severe diseases that affect 1 in 4,300 people. Moreover, very low levels of mutated mtDNA seem to be present in every person worldwide. These may increase with time and associate with late-onset degenerative diseases such as Parkinson disease, Alzheimer disease, and common cancers. Mutations in mtDNA are transmitted down the maternal lineage, following a poorly understood pattern of inheritance. Recent findings have indicated existence in the female germline of a purifying filter against deleterious mtDNA variants. Although the underlying mechanism of this filter is largely unknown, it has been suggested to rely on autophagic degradation of dysfunctional mitochondria or selective replication/transmission of non-deleterious variants. Thus, understanding the mechanisms regulating mitochondrial inheritance is important both to improve diagnosis and develop therapeutic tools for preventing transmission of mtDNA-encoded diseases., (© 2018 International Federation for Cell Biology.)

Importance: Medical errors and adverse events (AEs) are common among hospitalized children. While clinician reports are the foundation of operational hospital safety surveillance and a key component of multifaceted research surveillance, patient and family reports are not routinely gathered. We hypothesized that a novel family-reporting mechanism would improve incident detection., Objective: To compare error and AE rates (1) gathered systematically with vs without family reporting, (2) reported by families vs clinicians, and (3) reported by families vs hospital incident reports., Design, Setting, and Participants: We conducted a prospective cohort study including the parents/caregivers of 989 hospitalized patients 17 years and younger (total 3902 patient-days) and their clinicians from December 2014 to July 2015 in 4 US pediatric centers. Clinician abstractors identified potential errors and AEs by reviewing medical records, hospital incident reports, and clinician reports as well as weekly and discharge Family Safety Interviews (FSIs). Two physicians reviewed and independently categorized all incidents, rating severity and preventability (agreement, 68%-90%; κ, 0.50-0.68). Discordant categorizations were reconciled. Rates were generated using Poisson regression estimated via generalized estimating equations to account for repeated measures on the same patient., Main Outcomes and Measures: Error and AE rates., Results: Overall, 746 parents/caregivers consented for the study. Of these, 717 completed FSIs. Their median (interquartile range) age was 32.5 (26-40) years; 380 (53.0%) were nonwhite, 566 (78.9%) were female, 603 (84.1%) were English speaking, and 380 (53.0%) had attended college. Of 717 parents/caregivers completing FSIs, 185 (25.8%) reported a total of 255 incidents, which were classified as 132 safety concerns (51.8%), 102 nonsafety-related quality concerns (40.0%), and 21 other concerns (8.2%). These included 22 preventable AEs (8.6%), 17 nonharmful medical errors (6.7%), and 11 nonpreventable AEs (4.3%) on the study unit. In total, 179 errors and 113 AEs were identified from all sources. Family reports included 8 otherwise unidentified AEs, including 7 preventable AEs. Error rates with family reporting (45.9 per 1000 patient-days) were 1.2-fold (95% CI, 1.1-1.2) higher than rates without family reporting (39.7 per 1000 patient-days). Adverse event rates with family reporting (28.7 per 1000 patient-days) were 1.1-fold (95% CI, 1.0-1.2; P = .006) higher than rates without (26.1 per 1000 patient-days). Families and clinicians reported similar rates of errors (10.0 vs 12.8 per 1000 patient-days; relative rate, 0.8; 95% CI, .5-1.2) and AEs (8.5 vs 6.2 per 1000 patient-days; relative rate, 1.4; 95% CI, 0.8-2.2). Family-reported error rates were 5.0-fold (95% CI, 1.9-13.0) higher and AE rates 2.9-fold (95% CI, 1.2-6.7) higher than hospital incident report rates., Conclusions and Relevance: Families provide unique information about hospital safety and should be included in hospital safety surveillance in order to facilitate better design and assessment of interventions to improve safety.

The use of telepathology for clinical applications in Canada has steadily become more attractive over the last 10 years, driven largely by its potential to provide rapid pathology consulting services throughout the country regardless of the location of a particular institution. Based on this trend, the president of the Canadian Association of Pathologists asked a working group consisting of pathologists, technologists, and healthcare administrators from across Canada to oversee the development of guidelines to provide Canadian pathologists with basic information on how to implement and use this technology. The guidelines were systematically developed, based on available medical literature and the clinical experience of early adopters of telepathology in Canada. While there are many different modalities and applications of telepathology, this document focuses specifically on whole-slide imaging as applied to intraoperative pathology consultation (frozen section), primary diagnosis, expert or second opinions and quality assurance activities. Applications such as hematopathology, microbiology, tumour boards, education, research and technical and/or standard-related issues are not covered.

Purpose: To determine whether dynamic contrast material-enhanced (DCE) computed tomography (CT) can help identify hepatic tumor perfusion response to vascular remodeling induced by antiangiogenesis treatment in a rabbit model., Materials and Methods: The study was approved by the Animal Use Subcommittee of the University Council on Animal Care. DCE CT hepatic perfusion measurements were performed in the livers of 20 rabbits implanted with VX2 carcinoma. Vascular remodeling was induced with thalidomide dissolved in dimethyl sulfoxide and sterile water, starting at a tumor diameter of 0.7 cm±0.1 and continuing until metastatic lung nodules were observed. The control group (n=8) was given an equivalent volume of the vehicle. The therapy group was subdivided into animals that survived for more than 24 days without lung metastasis (responder group, n=5) or those that survived for less than 24 days (nonresponder group, n=7). Data were analyzed with the Kruskal-Wallis or Friedman rank test and reported as medians and interquartile ranges., Results: DCE CT depicted differential perfusion change within the therapy group after treatment. By day 4, hepatic blood volume (HBV) in the responder group decreased by 29.2% (-32.5% to -11.8%) relative to that before treatment and was significantly different from that in the nonresponder (P=.048) and control (P=.011) groups, where HBV remained stable. By day 8, hepatic artery blood flow decreased by 50.0% (-59.08% to -21.05%) relative to that before treatment in the responder group and was significantly different from that in the nonresponder and control groups (P=.030 for both), which remained stable at -3.5% (-8.5% to 28.7%, P=.50) and -10.0% (-33.8% to 10.4%, P=.48), respectively., Conclusion: DCE CT can help differentiate responders from nonresponders by their early differential perfusion response to antiangiogenesis therapy., (© RSNA, 2012.)

The purpose of this study was to determine if the quality of stored stallion semen doses could be enhanced by the scaled-up version of Single Layer Centrifugation using Androcoll-E-Large. Three semen doses from each of fifteen stallions were transported overnight to the Swedish University of Agricultural Sciences (SLU) for processing 24 h after semen collection. Sperm quality in the resulting SLC-selected samples was significantly improved compared to the uncentrifuged samples: mean progressive motility was increased by 8% on the day of processing (P < 0.001) and by 13% after 24 h cold storage (P < 0.001), normal morphology was increased by 4% (P < 0.01), whereas mean %DFI was decreased by 2% (P < 0.001). When these SLC-selected samples were compared retrospectively to fresh samples processed by SLC with Androcoll-E Small, sperm quality was found to be similar, although it was not maintained for as long in the sperm samples stored before SLC. These results suggest an additional option for improving sperm quality in stallion semen doses for artificial insemination., (Copyright © 2011 Elsevier Inc. All rights reserved.)

Background. Whether or not the familial form of papillary thyroid carcinoma is more aggressive than the sporadic form of the disease remains controversial. Methods. To explore this question and whether or not increased aggressiveness is more apparent in families with multiple affected members, we performed a chi square by trend analysis on our patients clinical and pathologic data comparing: first degree families with three or more affected members versus first degree families with two affected members versus sporadic cases of papillary thyroid carcinoma. Results. No statistically significant trends were seen for any presenting surgical pathology parameter, age at presentation, length of follow-up or gender distribution. The familial groups exhibited significant trends for higher rates of reoperation (P = 0.05) and/or requiring additional radioactive iodine therapy (P = 0.03), distant metastases (P = 0.003) and deaths (P = 0.01). These aggressive features were most apparent in certain families with three or more affected members. Conclusions. Using the chi square by trend analysis, a significant trend was seen for the familial form of papillary thyroid cancer to possess more aggressive features than the sporadic disease. Prompt recognition of the familial nature of the disease may provide earlier diagnosis and treatment in similarly affected family members.

Purpose: To evaluate in situ the anticariogenic effect of fluoride and MDPB containing adhesive systems at the restoration interface, by microhardness tests., Methods: 120 fragments containing preparations for resin composite restorations performed at the cemento-enamel junction were randomly distributed among the adhesive systems to be tested. The adhesive systems were applied in accordance with the manufacturers' instructions: Optibond FL, Adper Single Bond 2, Prime & Bond 2.1, Optibond Solo Plus, Adper Prompt, Clearfil Protect Bond and restored with the nanoparticulate resin composite Z350. Twenty volunteers used a palatal appliance containing fragments restored with each adhesive system for 21 days, and applied 20% sucrose on them eight times a day to simulate a high cariogenic challenge. Microhardness tests were performed at different depths (20 microm, 40 microm and 60 microm from the occlusal margin of the restoration) and at different distances (100 microm, 200 microm and 300 microm from the adhesive interface)., Results: ANOVA showed that for enamel, there was significant difference between the adhesive systems (P=0.0106); the interaction adhesive system*distance was a significant (P=0.0006), and the one-step self-etching adhesive system containing fluoride (Adper Prompt) presented a higher anticariogenic effect. However, for dentin, the adhesive system used did not interfere in decreasing the severity of caries formation.

Background: In 1996, the American Academy of Pediatrics (AAP) published a practice parameter recommending that lumbar puncture (LP) be strongly considered in infants younger than 12 months presenting with a first febrile seizure., Objective: We sought: (1) to determine if the recommendations of the AAP are being followed by pediatric emergency medicine-trained physicians at our institution; (2) to describe the rate of meningitis among patients with febrile seizure who underwent LP; and (3) to determine if there were differences in performance of LP if children were younger or pretreated with antibiotics., Methods: A retrospective chart review of patients aged 6 to 12 months presenting with first simple febrile seizure to the emergency department (ED) at Miami Children's Hospital was conducted between January 2001 and November 2005., Results: A total of 242 ED records with a discharge diagnosis including the term "febrile seizure," "seizure," or "meningitis" were identified. Of those, 56 met inclusion criteria for first simple febrile seizure. Lumbar puncture was performed in 28 patients (50%) that met inclusion criteria. Younger patients were no more likely to have LP performed than older patients (P = 0.15). Ten children (17.8%) received antibiotics before the ED visit; of these, 4 (40%) underwent LP in the ED. Children who presented with first simple febrile seizure to our institution who were pretreated with antibiotics were no more likely to have LP performed than those who were not receiving antibiotics (P = 0.48). All cerebrospinal fluid cultures were sterile., Conclusion: The AAP recommendations regarding LP in patients 6 to 12 months of age with first simple febrile seizure are not being strictly adhered to. The AAP recommendations regarding simple febrile seizures were conceived in a different epidemiologic era of disease pathology with data not representative of current prevalence and etiologic issues and need to be revisited.

Purpose: To assess the shear bond strength of resin composite to human enamel and dentin after using a whitening dentifrice containing carbamide peroxide for 21 days., Methods: Thirty enamel and 30 dentin slabs were embedded, flattened and randomly divided into three groups (n=10) that received different treatments: carbamide peroxide containing dentifrice (Rembrandt Plus), fluoride containing dentifrice (Close Up with fluoride), and immersion in artificial saliva as the control group. Applications were made for a 15-minute period daily, immersing the slabs in a suspension with distilled water and dentifrice in the ratio of 3:1 (weight) for 21 days. For the rest of the time, the slabs were kept in an artificial saliva solution. After the last application, an adhesive system (Single Bond) was used to bond resin-based composite cylinders (Z100) to the enamel and dentin surfaces for the shear bond strength tests. These tests were carried out in a universal testing machine at a speed of 0.5 mm/minute., Results: ANOVA and the Tukey test for enamel and Kruskal-Wallis and the Dunn Method for dentin, showed significant differences between slabs treated with Rembrandt Plus (REM) and the artificial saliva control group, with higher values for REM (P < 0.05). There were no differences in mean bond strengths of enamel and dentin treated with Close Up with fluoride (CLO) and REM, nor were any differences shown between CLO and the artificial saliva control group. A whitening dentifrice containing carbamide peroxide increased the bond strength of restorative systems.

Purpose: The aim of this study was to assess the shear bond strength of an adhesive restorative system on sound and demineralized dentin after the use of a papain-based agent., Methods: Forty human dentin slabs were randomly distributed into 4 groups: (1) sound dentin slabs that received an application of papain-based gel (N=10); (2) sound dentin slabs that did not receive a papain-based gel application (N=10); (3) demineralized slabs that received an application of the agent (N=10); and (4) demineralized slabs that did not receive an application of the agent (N=10). After manual excavation and use of the chemomechanical agent, the slabs were restored with a total etch adhesive system and microhybrid resin composite. The test specimens were individually stored in a damp environment for 7 days, and the shear bond strength test was performed using a universal test machine at a speed of 0.5 mm/min. The fragments were observed under a stereoscopic microscope to assess the fracture mode., Results: Fracture mode assessment showed adhesive and cohesive type fractures in resin for all the groups. The analysis of variance and the Tukey test showed that there were no differences in the shear bond strength means among the groups (P>.05)., Conclusions: The use of a papain-based gel to remove dental caries did not interfere in the bond strength of restorative materials to dentin.

Chinese star anise (Illicium verum Hook f.) is a well-known spice used in many cultures. Many populations use it as a treatment for infant colic. Japanese star anise (Illicium anisatum L), however, has been documented to have both neurologic and gastrointestinal toxicities. Recently, concern has been raised regarding the adulteration of Chinese star anise with Japanese star anise. We report 7 cases of adverse neurologic reactions in infants seen with the home administration of star anise tea. In addition, we have found evidence that Chinese star anise has been contaminated with Japanese star anise. More strict federal regulation of the import of star anise into the United States is warranted. Star anise tea should no longer be administered to infants because of its potential danger in this population.

The present study was undertaken to determine whether human decay accelerating factor (hDAF) transgene would prevent hyperacute rejection (HAR) while perfused with human blood or extracorporeally in baboons. Four hDAF pig kidneys and three non-hDAF pig kidneys were perfused ex vivo with fresh human blood for 6 h. Additionally four hDAF pig kidneys and four non-hDAF pig kidneys were extracorporeally perfused in baboons and pigs, respectively, for 3 h. In ex vivo perfusion, the color of hDAF pig kidneys remained pink at the end of 6-h perfusion and they had normal histology, while non-hDAF kidneys developed HAR. HDAF pig kidneys had superior function over non-transgenic pig kidneys. Urine output was 17.31 +/- 3.70 ml/h for hDAF pig kidneys, and only 5.81 +/- 0.26 ml/h for non-hDAF kidneys (P < 0.05). Creatinine clearance was 1.16 +/- 1.24 ml/min for hDAF kidneys and 0.22 +/- 0.15 ml/min for non-hDAF kidneys (P < 0.05). Other functional data including potassium, urine specific density, and osmolality were normal in the hDAF kidneys, while in non-hDAF kidneys, serum potassium was elevated to over 9 mmol/l by the end of perfusion (P < 0.01). Non-hDAF kidneys also lost more sodium through urine than hDAF kidneys (173.67 +/- 14.05 mmol/l vs. 109 +/- 31 mmol/l, P < 0.05). In the extracorporeal perfusion, all the baboons tolerated the procedure well with normal hemodynamic and hemotologic profiles. These baboons were well until killed 42 to 56 days after perfusion, although their antiporcine antibodies were greatly elevated. We conclude that hDAF transgene protects against HAR, allowing the pig kidney to function normally while perfused with human blood, and that extracorporeal perfusion using hDAF pig kidneys is a safe procedure in baboons.

Objective: In 1998, we implemented a clinical imaging protocol in which children with suspected appendicitis underwent ultrasonography (US) followed by computed tomography (CT). We sought to determine the impact of the US-CT protocol on changes in perforation and negative appendectomy rates., Methods: Children with unequivocal presentations for appendicitis went to the operating room without entering the imaging protocol. Using a modified time series design, we analyzed a prospective and retrospective cohort of consecutive patients who were admitted from the emergency department for suspected appendicitis. The perforation and negative appendectomy rates were computed for the periods before and after implementation of the imaging protocol and adjustment for time trends was made., Results: A total of 1338 children were identified. Eight hundred ten (60.5%) children had equivocal clinical findings. A total of 920 patients were admitted for suspected appendicitis before the protocol was implemented; 526 (57.2%) of the 920 children had appendicitis, and 186 (35.4%) of them had perforation. A total of 91 (14.7%) of 617 had negative appendectomies. After the protocol was implemented, 418 patients were admitted for suspected appendicitis; 328 (78.5%) had appendicitis with 51 (15.5%) perforated. There were 14 (4.1%) of 342 cases of negative appendectomies. After implementation of the imaging protocol, the perforation rate decreased from 35.4% to 15.5%, and the negative appendectomy rate decreased from 14.7% to 4.1%. After secular time trends were adjusted for, the imaging protocol continued to have a strong association with a reduction in perforation rate and negative appendectomy rate., Conclusion: The implementation of an imaging protocol using US and CT resulted in a marked decrease in the perforation and negative appendectomy rates in children with suspected appendicitis.

The aim of this study was to determine if human decay-accelerating factor (hDAF) protects against hyperacute rejection in an ex vivo liver perfusion system using human blood. Pig livers were perfused ex vivo via the portal vein for an average of 5-6 h using a membrane oxygenator. Three groups were studied. Group I: Wild-type pig livers were alloperfused with fresh pig blood (n = 5). Group II: Wild-type pig livers were xenoperfused with fresh human blood (n = 5). Group III: hDAF transgenic pig livers were xenoperfused with fresh human blood (n = 5). The graft ischemic time, ratio of perfusate volume to liver weight, flow rate, and perfusate hematocrit were similar in each group. The hDAF livers perfused with human blood (Group III) had a lower ALT level, less protein and albumin losses, lower bilirubin levels in the perfusate, less weight gain, and greater bile production than the wild-type livers perfused with human blood. Histology showed classic features of hyperacute rejection in Group II, including massive hemorrhage, severe vasculitits, fibrin and C5b-9 deposition, and endothelial damage within 1 h of perfusion, whereas liver histology studies in Groups I and III were near normal. IgG and IgM deposits were seen in the xenoperfused livers. Electron microscopy (EM) and immuno-EM showed loss of endothelial cells, trapping of white blood cells and platelets, and diffuse fibrin deposits in Group II only. hDAF pig livers perfused with human blood showed superior function and histology when compared with wild-type pig livers. These data suggest that (1) hyperacute rejection may contribute to the inconsistent results using wild-type pig livers for extracorporeal liver support and (2) genetically modified pigs that express hDAF may provide a better donor source than wild-type pigs for extracorporeal liver support.

Amiodarone is an iodinated benzofuran derivative class III antiarrhythmic that is highly effective in suppressing ventricular and supraventricular arrhythmias. It is also associated with an imposing side effect profile, which often limits its use. Numerous adverse effects have been documented including skin discolouration, photosensitivity, hepatitis, thyroid dysfunction, corneal deposits, pulmonary fibrosis, bone marrow suppression and drug interactions. These side effects are thought to be correlated with the total cumulative dose of amiodarone, but idiopathic reactions have been reported. The majority of adverse reactions resolve with discontinuation of the drug; however, rapid progression may occur, which may be fatal. The present report documents a patient who had a combination of serious amiodarone toxicities that, once recognized, were treated and eventually resulted in a good outcome.

The present study was undertaken to establish a rat-to-mouse vascularized small bowel xenotransplantation model to study acute vascular and hyperacute xenograft rejection, and xenogenic cell migration. Lewis rat small bowel grafts were transplanted heterotopically to group 1, Balb/c mice, and group 2, Balb/c mice pre-sensitized with a donor spleen cell injection. The grafts were examined by serial pathology and flow cytometry. In group 1, acute vascular rejection was present by the 5th post-operative day (POD). Immunohistology showed a strong endothelial deposition of IgG, IgM and C3, associated with a minimal lymphocytic infiltrate. There was a vigorous cell migration from the recipient to the graft, in which recipient origin cells comprised 80.1+/-6.9% of the graft mesenteric lymph node by POD 3. However, there was almost no cell migration from the graft to the recipient. The intestinal xenografts in the group 2 showed massive hemorrhage, fibrin deposition, vascular congestion and thrombosis 60 min after transplantation. IgG and C3 were present on the endothelium as early as 1 min after reperfusion. The vigorous humorally-mediated vascular damage and rapid elimination of donor cells seen with intestinal xenograft rejection are distinct from the usual picture of allograft rejection. Hyperacute rejection can be induced by recipient pre-sensitization with donor spleen cells. The potential advantages of studying xenotransplantation in this model include: (1) the wide range of immunologic reagents available for mice; (2) the opportunity to study the progression of vascular damage easily by performing serial biopsies in the same animal; and (3) the opportunity to study, in vivo, two-way cellular response by examining cell trafficking in the mesenteric lymph nodes.

Background: Clinical intestinal transplantation has been plagued by frequent and severe graft rejection. It has been proposed that the major histocompatibility complex (MHC) antigens might play a critical role in this process owing to their extensive expression on enterocytes and mucosa-associated immune cells., Methods: The present study examined the role of MHC antigens in intestinal graft rejection using MHC class I-deficient and MHC class II-deficient donors., Results: Grafts with normal MHC expression were rejected by 9 days, whereas survival was prolonged to 14 days in the MHC class II-deficient grafts (P=NS) and to 20 days in the MHC I-deficient grafts (P<0.002). In all groups, early rejection was characterized by (1) increased crypt cell apoptosis, as detected by the terminal deoxynucleotidyltransferase-mediated dUTP-biotin nick end labeling (TUNEL) technique of in situ labeling; and (2) the increased expression of perforin and a CD8 phenotype in the graft-infiltrating cells., Conclusions: These data suggest that MHC antigens, CD8-positive T cells, and perforin-expressing cells contribute to intestinal graft rejection. Apoptosis of the progenitor epithelial crypt cells during early intestinal rejection may impair the gut's ability to regenerate and repair mucosal damage.

Post-transplantation lymphoproliferative disorder (PTLD) and acute rejection are two serious complications of orthotopic liver transplantation that can have a similar histologic appearance. We undertook the present study to assess the best way to distinguish these two entities. We studied histologic features, immunophenotyping, and Epstein-Barr virus (EBV) status, as assessed by immunohistochemical stain and in situ hybridization (ISH), in three groups: Group I, 8 cases of PTLD post-orthotopic liver transplantation with liver involvement; Group II, 15 cases diagnosed with acute liver rejection (control group); and Group III, a subset of 6 biopsy specimens from 4 patients of Group I whose graft rejection was diagnosed within the 2 months preceding the diagnosis of PTLD. The mean proportion of plasma to plasmacytoid cells in most cases from Group I was more than 40%, whereas from Group II it was less than 25% (P = .0001). There was a higher number of B lymphocytes than T lymphocytes in Group I. The numbers of mitotic figures and immunoblasts were significantly different in the two groups (P < .0001 and P = .0005, respectively), being higher in the patients with PTLD. EBV immunostain was most specific for the diagnosis of PTLD (75% positive in Group I, negative in Group II). ISH for EBV-encoded RNA was positive in 87% of cases in Group I and only 6.6% of cases in Group II (P = .0005). In Group III, four of the six liver biopsy specimens had a low plasma cell count and were negative for EBV studies. The other two biopsy specimens in this group had 70 to 80% plasma cell infiltrate, in addition to positive EBV immunostain and ISH in one, for which tissue was available for study. We conclude that viral studies and assessment of the number of plasma cells and B lymphocytes can help to distinguish between acute rejection and early PTLD.

Background: The urinary bladder is an uncommon site for primary oat cell carcinoma, with as few as 30 histologically diagnosed cases described in the literature. The first reported cytologic diagnosis was made in 1991., Case: A 76-year-old female presented with gross hematuria. Voided urine cytology showed small, dark cells with little visible cytoplasm and coarse chromatin. Subsequent histopathologic, immunopathologic and electron microscopic studies confirmed the diagnosis of primary oat cell carcinoma., Conclusion: The diagnosis of oat cell carcinoma is well recognized in respiratory cytology. The same cells found in a urinary specimen may suggest a primary oat cell tumor in conjunction with negative clinical and radiologic investigations for a primary tumor elsewhere.

Purpose: The antitumor effect of intravesical mycobacterium cell wall (MCW) therapy on orthotopic and heterotopic bladder tumors in the mouse was assessed with magnetic resonance imaging (MRI)., Materials and Methods: The live bacillus Calmette Guerin (BCG) organism was replaced with a cell wall extract derived from the outer capsule of Mycobacterium phlei. This alternative form of intravesical therapy was used with the aim of reducing the toxicity associated with the live mycobacterium organism without compromising efficacy. Response to multiple doses of intravesical MCW and BCG was assessed in mice with established MBT-2 tumors after transurethral tumor implantation., Results: Serial MRI of BCG-treated mice revealed significant tumor regression. The MR images correlated well with the corresponding histology of the whole mount bladder sections. Treatment with MCW also resulted in significant inhibition of tumor growth compared with control untreated animals (p < 0.05) although the antitumor effect was less pronounced than that of live BCG. Treatment was well tolerated in the MCW group with no apparent ill effects. Flow cytometric (FCM) analysis of bladder washings with phenotype-specific monoclonal antibodies revealed predominantly a CD3+ T cell infiltrate in the control and BCG-treated as well as the MCW-treated mice. The CD4+ (helper/inducer) subset of T cells predominated over the CD8+ (suppressor/cytotoxic) subset in both the BCG- and MCW-treated animals, and the CD4+/CD8+ ratio in both of the treated groups differed significantly from that of the control untreated groups., Conclusion: Intravesical MCW appears to invoke a similar inflammatory response in the mouse bladder mucosa as the live BCG organism and retains an antitumor action. It deserves further evaluation as a potential antitumor agent against bladder cancer. A Phase II clinical trial is now underway.

Purpose: To correlate the stereotaxic core needle biopsy results with those of surgical biopsy in patients with atypical lobular or ductal hyperplasia (atypical hyperplasia) diagnosed at stereotaxic core needle biopsy (SCNB)., Methods: We retrospectively reviewed the mammograms and pathology reports of 358 consecutive SCNBs performed in 323 patients. The results of SCNBs of 22 lesions reported as atypical hyperplasia were correlated with histologic findings at surgical biopsy., Results: A histologic diagnosis of atypical hyperplasia at SCNB was found to be a poor predictor of the final surgical results. In the 19 patients with 22 lesions, surgical biopsy and SCNB results were in disagreement in 16, partial agreement in two, and complete agreement in only four lesions. Furthermore, five cases of atypical hyperplasia were shown to have invasive carcinoma on open biopsy, and five had ductal carcinoma in situ in the surgical biopsy, none of which was present on SCNB., Conclusion: Given the frequent occurrence of malignancy in patients diagnosed with atypical hyperplasia by SCNB, it is recommended that all such patients undergo excisional biopsy.

Rejection continues to be the single largest impediment to successful organ transplantation. Antilymphocyte globulin, which contains antibodies that react with the leukocyte common antigen known as CD45, has proved to be one of the most effective agents for preventing rejection. We have shown earlier that a monoclonal antibody directed against the RB isoform of CD45 substantially inhibits the alloreactivity of human CD4+ lymphocytes in vitro. Here we investigate whether CD45RB could be an appropriate target for preventing renal allograft rejection in mice. Mice treated with two injections of a monoclonal antibody (MB23G2) raised against CD45RB protein all survived and had normal renal function. Furthermore, this antibody reversed acute rejection when therapy was delayed until day 4, and the mice survived for their natural lifespan. The immunosuppression achieved may find application in the prevention and treatment of transplant rejection in man.

To investigate whether cortisol secretory patterns are associated with a response to cyproheptadine treatment in Cushing's disease, we studied two patients with a hyperpulsatile pattern and one patient with a hypopulsatile pattern before and during chronic cyproheptadine therapy (24 mg daily). In the two patients with a hyperpulsatile cortisol secretory pattern, pituitary magnetic resonance imaging with gadolinium did not reveal a pituitary adenoma, whereas in the patient with a hypopulsatile cortisol secretory pattern, a microadenoma was identified. Plasma cortisol levels were measured every 30 min for 24 h. In the two patients with a hyperpulsatile cortisol secretory pattern, chronic treatment with cyproheptadine resulted in sustained clinical and biochemical improvement and normalization of the median of absolute and relative increments in cortisol spikes. In the patient with a hypopulsatile cortisol secretory pattern, only a reduction of cortisol spikes was noticed during treatment. These results suggest that patients with Cushing's disease who are characterized by a hyperpulsatile cortisol secretory pattern and in whom no pituitary lesion can be identified by magnetic resonance imaging, cyproheptadine treatment may be useful.

Rapid and severe rejection remains a major obstacle to successful clinical intestinal transplantation (IT). The aggressive nature of rejection in IT has been attributed to the increased massive immune stimulus provided by large numbers of resident lymphocytes, antigen presentation capacity of enterocytes, and graft damage mediated by luminal microflora. Early small bowel expression of proinflammatory cytokines, MHC class II, and adhesion molecules may also promote IT rejection, but the lack of a mouse model has hampered extensive studies of gene expression in IT. Using a recently developed surgical model, we examined the temporal pattern of gene expression in CB6F1 (H-2b/d) vascularized, heterotopic intestinal allografts transplanted into BALB/c (H-2d) mice. Although histological evidence of rejection was not present until day 7 in allografts, Northern blot analysis demonstrated increases in TNF alpha gene transcripts as early as day 3, followed by the expression of IL-1 beta, intercellular adhesion molecule-1, and MHC class II by day 5. Using reverse-transcriptase polymerase chain reaction, IFN-gamma was detected in allografts by day 3 and persisted to day 10. In contrast, IL-2, IL-4, IL-5, and IL-6 mRNA transcripts peaked by day 5 and then decreased, suggesting that both Th1 and Th2 subsets are involved in the rejection of unmodified small bowel allografts. The early and progressive expression of TNF alpha and IL-1 beta as well as IFN-gamma, intercellular adhesion molecule-1, and MHC class II in IT rejection may contribute to the difficulty in controlling IT rejection with present immunosuppression.

Colon transplantation has been proposed as a method to improve the function of an intestinal allograft. The present study examined the risk of colon rejection and the effect of FK506 on colon rejection in BN-->LEW rats with orthotopic bowel transplants. The first 4 groups included rats with untreated allografts (group 1), rats with isografts treated with 0.6 mg/kg FK506 (group 2), rats with allografts treated with 0.6 mg/kg FK506 (group 3), and rats with allografts treated with 0.4 mg/kg FK506 (group 4). In each of these groups (10-12 rats), half of the animals received a small bowel graft only (SB), while the other half received a small bowel, ascending colon, and cecum graft (SBC). The animals were followed daily until they died or were killed at 4 weeks. In group 5, an additional 18 untreated rats with SBC allografts were randomly killed on the third, fifth, seventh, and tenth postoperative days to study the sequential histopathologic and immunopathologic changes of colon rejection. There was no difference in survival, body weight, nutritional parameters, or bacterial contamination after SB and SBC transplantation. Intestinal transit was slower after SBC than SB transplantation (P < 0.05). Sequential histopathologic studies revealed that (1) the severity and time course of colon rejection was similar to small intestine rejection, and (2) the features of colon rejection were similar to ulcerative colitis. There was no evidence of graft-versus-host disease after SBC transplantation. In summary, adding a segment of large bowel to a small bowel allograft does not increase the risk of rejection or surgical complications. The transplanted colon slows intestinal transit. Treatment with FK506 effectively prevents colon rejection. These data suggest that adding a colon graft may improve the outcome of clinical small bowel transplantation.