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The Swedish national parliamentary election of 2018 took place amidst considerable concern over the role of misinformation. This paper examines the role of digital media during the election against the background of the Swedish media system. It focuses on the role of bots and how they supported the Sweden Democrats, whose agenda was also promoted by anti-immigrant alternative news websites. This article reports on a study of Twitter that used computational techniques to distinguish bots from genuine accounts across hashtags related to the election and Swedish politics (such as #valet2018). I examine which parties are supported and criticised by bots and by genuine accounts, and discuss the content of the tweets. In this article, I place bots in the context of broader debates about the role of digital media in politics and argue that misinformation and alternative news websites will demand continued future vigilance.

Objective: Findings concerning the effects of hormone therapy (HT) on cognition and dementia are mixed, with some trials suggesting increased harm at older ages. Personality, like cognition, changes with dementia, but no clinical trials to date have examined the effects of HT on personality traits. This study aimed to determine the effects of HT on personality traits in older men and women., Method: Secondary data analysis was performed from randomized, double-blind, placebo-controlled cross-over studies of menopausal HT in women and testosterone therapy (TT) in men. Participants were community-dwelling cognitively normal adults (mean age = 75.2 years), including 29 men and 22 women. Three months of hormone intervention (for women, 0.625 mg/day conjugated equine estrogen with or without 2.5 mg/day medroxyprogesterone acetate; for men, 200 mg intramuscular testosterone enanthate every 2 weeks) were crossed over with 3 months of identical placebo with a 3-month washout between intervention phases. The main outcome measure was neuroticism and conscientiousness personality domains and facets assessed with the Revised NEO Personality Inventory (NEO-PI-R) after the active and placebo intervention phases., Results: In linear mixed-effect models, HT in women decreased conscientiousness ( p  < 0.01) and the conscientiousness facet of achievement striving ( p  < 0.01), and increased vulnerability, a facet of neuroticism ( p  < 0.05). Testosterone in men decreased conscientiousness ( p  < 0.05) and the conscientiousness facet of dutifulness ( p  < 0.05), and increased vulnerability ( p  < 0.05)., Conclusion: In a preliminary study of healthy older adults, HT and TT formulations produced adverse changes in vulnerability and conscientiousness facets that parallel personality changes in dementia.

Objective: This study aimed to examine sex differences in factors associated with mood and anxiety in midlife men and women during the COVID-19 pandemic., Methods: During a remote visit, 312 adults aged 40-60 years (167 female; 23.6% perimenopausal) from the Human Connectome Project in Aging completed PROMIS measures of depression, anxiety and anger/irritability; perceived stress; and questions about social support, financial stress and menopause stage. Multivariate linear regression models assessed sex differences in mental health and the association of social support, financial stress and menopause stage with mental health., Results: Anxiety was higher in women than in men ( b  = 2.39, p  = 0.02). For women only, decreased social support was associated with increased anxiety ( b  = -2.26, p  = 0.002), anger/irritability ( b  = -1.89, p  = 0.02) and stress ( b  = -1.67, p  = 0.002). For women only, not having close family was associated with increased depressive symptoms ( b  = -6.60, p  = 0.01) and stress ( b  = -7.03, p  < 0.001). For both sexes, having children was associated with lower depressive symptoms ( b  = -3.08, p  = 0.002), anxiety ( b  = -1.93, p  = 0.07), anger/irritability ( b  = -2.73, p  = 0.02) and stress ( b  = -1.44, p  = 0.07). Menopause stage was unrelated to mental health., Conclusion: Social support, but not financial stress, influenced mental health during the COVID-19 pandemic at midlife, particularly for women.

Objective: Determine associations of endogenous estrogens with memory systems in the postmenopausal brain and evaluate clinical significance., Study Design: In the MsBrain cohort (n=199, mean age 59.3+3.9 years, 83.9% white), we examined the cross-sectional association of serum estradiol and estrone, measured using liquid chromatography-tandem mass spectrometry (LC-MS/MS), during a functional magnetic resonance imaging (fMRI) task of word encoding and recognition. To characterize the clinical significance of those associations, we examined the magnitude of activation in relation to a neuropsychological measures of memory and affect., Results: Endogenous estradiol was positively associated with activation in temporal and frontal cortices during encoding and negatively associated with one prefrontal region during recognition (p<.05). Activation in the left inferior frontal gyrus was associated with memory performance (β(SE)= 0.004(0.002), p<.05), and anxiety (β(SE)= -0.100(0.050), p<.05). The left middle frontal gyrus was associated with memory performance (β(SE)= 0.006(0.002), p<.01), depression, and anxiety. The left superior temporal gyrus (STG) was associated with depression (β(SE)= -0.083(0.036), p<.05) and anxiety (β(SE)= -0.134(0.058), p<.05). Estrone was positively associated with activation in a range of brain areas including bilateral STG and right superior frontal gyrus during encoding (p<.05). Activation of the left insula an precental gyrus were associated with symptoms of depression and anxiety. None related to memory., Conclusion: The function of brain areas critical to memory performance varies with estrogen levels in the postmenopause, even though those levels are low. Higher levels of estradiol may facilitate memory performance through enhanced function of temporal and frontal cortices during encoding of verbal material., (© The Author(s) 2024. Published by Oxford University Press on behalf of the Endocrine Society. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com. See the journal About page for additional terms.)

Background: Women carrying the APOE4 allele are at greater risk of developing Alzheimer's disease (AD) from ages 65-75 years compared to men. To better understand the elevated risk conferred by APOE4 carrier status among midlife women, we investigated the separate and interactive associations of endogenous estrogens, plasma AD biomarkers, and APOE4 carrier status on regional brain volumes in a sample of late midlife postmenopausal women., Methods: Participants were enrolled in MsBrain, a cohort study of postmenopausal women ( n  = 171, mean age = 59.4 years, mean MoCA score = 26.9; race = 83.2% white, APOE4 carriers = 40). Serum estrone (E1) and estradiol (E2) levels were assessed using liquid chromatography-tandem mass spectrometry. APOE genotype was determined using TaqMan SNP genotyping assays. Plasma AD biomarkers were measured using single molecule array technology. Cortical volume was measured and segmented by FreeSurfer software using individual T1w MPRAGE images. Multiple linear regression models were conducted to determine whether separate and interactive associations between endogenous estrogen levels, plasma AD biomarkers (Aβ42/Aβ40, Aβ42/p-tau181), and APOE4 carrier status predict regional brain volume (21 regions per hemisphere, selected a priori ); and, whether significant interactive associations between estrogens and AD biomarkers on brain volume differed by APOE4 carrier status., Results: There was no main effect of APOE4 carrier status on regional brain volumes, endogenous estrogen levels, or plasma AD biomarkers. Estrogens did not associate with regional brain volumes, except for positive associations with left caudal middle frontal gyrus and fusiform volumes. The interactive association of estrogens and APOE4 carrier status on brain volume was not significant for any region. The interactive association of estrogens and plasma AD biomarkers predicted brain volume of several regions. Higher E1 and E2 were more strongly associated with greater regional brain volumes among women with a poorer AD biomarker profile (lower Aβ42/40, lower Aβ42/p-tau181 ratios). In APOE4 -stratified analyses, these interactions were driven by non- APOE4 carriers., Conclusion: We demonstrate that the brain volumes of postmenopausal women with poorer AD biomarker profiles benefit most from higher endogenous estrogen levels. These findings are driven by non- APOE4 carriers, suggesting that APOE4 carriers may be insensitive to the favorable effects of estrogens on brain volume in the postmenopause., Competing Interests: RT reported receiving personal fees from Astellas Pharma, Bayer, Hello Therapeutics, Happify Health, and Vira Health outside the submitted work. HA reported receiving personal fees from Eisai outside the submitted work. PM reported receiving personal fees from Astellas Pharma, Bayer, Estrigenix, Alloy, and MidiHealth outside the submitted work. The remaining 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 © 2024 Wugalter, Schroeder, Thurston, Wu, Aizenstein, Cohen, Kamboh, Karikari, Derby and Maki.)

Given a large clinical database of longitudinal patient information including many covariates, it is computationally prohibitive to consider all types of interdependence between patient variables of interest. This challenge motivates the use of mutual information (MI), a statistical summary of data interdependence with appealing properties that make it a suitable alternative or addition to correlation for identifying relationships in data. MI: (i) captures all types of dependence, both linear and nonlinear, (ii) is zero only when random variables are independent, (iii) serves as a measure of relationship strength (similar to but more general than R2), and (iv) is interpreted the same way for numerical and categorical data. Unfortunately, MI typically receives little to no attention in introductory statistics courses and is more difficult than correlation to estimate from data. In this article, we motivate the use of MI in the analyses of epidemiologic data, while providing a general introduction to estimation and interpretation. We illustrate its utility through a retrospective study relating intraoperative heart rate (HR) and mean arterial pressure (MAP). We: (i) show postoperative mortality is associated with decreased MI between HR and MAP and (ii) improve existing postoperative mortality risk assessment by including MI and additional hemodynamic statistics., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Young et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Objective: This article will describe the current COVID-19 crisis and the evolving mental health concerns associated with it, discuss how mental health practice has changed, and ways in which psychiatric mental health nurse practitioners (PMHNPs) can adapt and prepare for the future., Method: A search of current literature on the COVID-19 crisis, and topics relevant to the mental health components associated with the pandemic are reviewed. Telemental health (TMH) and PMHNP practice are discussed as they relate to the unfolding picture of the viral pandemic., Results: The COVID-19 crisis is having far-reaching implications for mental health treatment and in particular for PMHNPs in practice settings. There have been widespread consequences of the containment measures used for the protection and mitigation of the disease. One such result has been the inability of patients to have face-to-face contact with their providers. The role of TMH has become increasingly important as an adaptation in professional practice., Conclusion: Technology has rapidly transformed traditional practice due to the COVID-19 crisis and there is strong evidence that it is well accepted by patients and providers. It is incumbent on PMHNPs to embrace TMH and become educated on best practices and TMH services.

Migraine is a common chronic neurological disease that disproportionately affects women. Migraine has significant negative effects on physical, emotional, and social aspects of health, and can be costly for patients, employers, and society as a whole. Growing evidence supports the roles of sex and gender in migraine risk, pathophysiology, presentation, diagnosis, treatment, and management. However, sex and gender differences in migraine have received limited attention, which can impede advancements in migraine detection, treatment, care, and education. The Society for Women's Health Research convened an interdisciplinary expert panel of researchers, clinicians, and advocates for a roundtable meeting to review the current research on sex and gender differences in migraine. This review summarizes discussions from the roundtable and prioritizes areas of need that warrant further attention in migraine research, care, and education. Examining sex and gender differences in migraine and addressing knowledge gaps will decrease the health and economic burden of migraine for both women and men.

Motivation: Although there is a rich literature on methods for assessing the impact of functional predictors, the focus has been on approaches for dimension reduction that do not suit certain applications. Examples of standard approaches include functional linear models, functional principal components regression and cluster-based approaches, such as latent trajectory analysis. This article is motivated by applications in which the dynamics in a predictor, across times when the value is relatively extreme, are particularly informative about the response. For example, physicians are interested in relating the dynamics of blood pressure changes during surgery to post-surgery adverse outcomes, and it is thought that the dynamics are more important when blood pressure is significantly elevated or lowered., Results: We propose a novel class of extrema-weighted feature (XWF) extraction models. Key components in defining XWFs include the marginal density of the predictor, a function up-weighting values at extreme quantiles of this marginal, and functionals characterizing local dynamics. Algorithms are proposed for fitting of XWF-based regression and classification models, and are compared with current methods for functional predictors in simulations and a blood pressure during surgery application. XWFs find features of intraoperative blood pressure trajectories that are predictive of postoperative mortality. By their nature, most of these features cannot be found by previous methods., Availability and Implementation: The R package 'xwf' is available at the CRAN repository: https://cran.r-project.org/package=xwf., Supplementary Information: Supplementary data are available at Bioinformatics online.

Assertive Community Treatment (ACT) is a model of care that provides comprehensive community-based psychiatric care for persons with serious mental illness. This model has been widely documented and has shown to be an evidence-based model of care for reducing hospitalizations for this targeted population. Critical ingredients of the ACT model are the holistic nature of their services, a team based approach to treatment and nurses who assist with illness management, medication monitoring, and provider collaboration. Although the model remains strong there are clear differences between urban and rural teams. This article describes present day practice in two disparate ACT programs in urban and rural Maine. It offers a new perspective on the evolving and innovative program of services that treat those with serious mental illness along with a review of literature pertinent to the ACT model and future recommendations for nursing practice. The success and longevity of these two ACT programs are testament to the quality of care and commitment of staff that work with seriously mentally ill consumers. Integrative care models such as these community-based treatment teams and nursing driven interventions are prime elements of this successful model.

Objective: Hemoglobin A 1c (A1C) is used in assessment of patients for elective surgeries because hyperglycemia increases risk of adverse events. However, the interplay of A1C, glucose, and surgical outcomes remains unclarified, with often only two of these three factors considered simultaneously. We assessed the association of preoperative A1C with perioperative glucose control and their relationship with 30-day mortality., Research Design and Methods: Retrospective analysis on 431,480 surgeries within the Duke University Health System determined the association of preoperative A1C with perioperative glucose (averaged over the first 3 postoperative days) and 30-day mortality among 6,684 noncardiac and 6,393 cardiac surgeries with A1C and glucose measurements. A generalized additive model was used, enabling nonlinear relationships., Results: A1C and glucose were strongly associated. Glucose and mortality were positively associated for noncardiac cases: 1.0% mortality at mean glucose of 100 mg/dL and 1.6% at mean glucose of 200 mg/dL. For cardiac procedures, there was a striking U-shaped relationship between glucose and mortality, ranging from 4.5% at 100 mg/dL to a nadir of 1.5% at 140 mg/dL and rising again to 6.9% at 200 mg/dL. A1C and 30-day mortality were not associated when controlling for glucose in noncardiac or cardiac procedures., Conclusions: Although A1C is positively associated with perioperative glucose, it is not associated with increased 30-day mortality after controlling for glucose. Perioperative glucose predicts 30-day mortality, linearly in noncardiac and nonlinearly in cardiac procedures. This confirms that perioperative glucose control is related to surgical outcomes but that A1C, reflecting antecedent glycemia, is a less useful predictor., (© 2018 by the American Diabetes Association.)

Background: When tracheal intubation is difficult or unachievable before surgery or during an emergent resuscitation, this is a critical safety event. Consensus algorithms and airway devices have been introduced in hopes of reducing such occurrences. However, evidence of improved safety in clinical practice related to their introduction is lacking. Therefore, we selected a large perioperative database spanning 2002 to 2015 to look for changes in annual rates of difficult and failed tracheal intubation., Methods: Difficult (more than three attempts) and failed (unsuccessful, requiring awakening or surgical tracheostomy) intubation rates in patients 18 yr and older were compared between the early and late periods (pre- vs. post-January 2009) and by annual rate join-point analysis. Primary findings from a large, urban hospital were compared with combined observations from 15 smaller facilities., Results: Analysis of 421,581 procedures identified fourfold reductions in both event rates between the early and late periods (difficult: 6.6 of 1,000 vs. 1.6 of 1,000, P < 0.0001; failed: 0.2 of 1,000 vs. 0.06 of 1,000, P < 0.0001), with join-point analysis identifying two significant change points (2006, P = 0.02; 2010, P = 0.03) including a pre-2006 stable period, a steep drop between 2006 and 2010, and gradual decline after 2010. Data from 15 affiliated practices (442,428 procedures) demonstrated similar reductions., Conclusions: In this retrospective assessment spanning 14 yr (2002 to 2015), difficult and failed intubation rates by skilled providers declined significantly at both an urban hospital and a network of smaller affiliated practices. Further investigations are required to validate these findings in other data sets and more clearly identify factors associated with their occurrence as clues to future airway management advancements., Visual Abstract: An online visual overview is available for this article at http://links.lww.com/ALN/B635.

Background: Patient handovers (handoffs) following surgery have often been characterized by poor teamwork, unclear procedures, unstructured processes, and distractions. A study was conducted to apply a human-centered approach to the redesign of operating room (OR)-to-ICU patient handovers in a broad surgical ICU (SICU) population. This approach entailed (1) the study of existing practices, (2) the redesign of the handover on the basis of the input of hand over participants and evidence in the medical literature, and (3) the study of the effects of this change on processes and communication., Methods: The Durham [North Carolina] Veterans Affairs Medical Center SICU is an 11-bed mixed surgical specialty unit. To understand the existing process for receiving postoperative patients in the SICU, ethnographic methods-a series of observations, surveys, interviews, and focus groups-were used. The handover process was redesigned to better address providers' work flow, information needs, and expectations, as well as concerns identified in the literature., Results: Technical and communication flaws were uncovered, and the handover was redesigned to address them. For the 49 preintervention and 49 postintervention handovers, the information transfer score and number of interruptions were not significantly different. However, staff workload and team behaviors scores improved significantly, while the hand over duration was not prolonged by the new process. Handover participants were also significantly more satisfied with the new handover method., Conclusions: An HCD approach led to improvements in the patient handover process from the OR to the ICU in a mixed adult surgical population. Although the specific handover process would unlikely be optimal in another clinical setting if replicated exactly, the HCD foundation behind the redesign process is widely applicable.

The frequency of neuropsychiatric disorders is greater than that of cancer, cardiovascular disease, and diabetes combined, and is growing at a faster rate than any other ailments in the United States or Europe. Despite a considerable need for the development of treatments for central nervous system disorders, pharmaceutical companies continue to reduce investment in this area of research. Of particular concern is the treatment of diseases and disorders that affect cognitive function, which are often given a lower priority for research investment than life threatening conditions or those with overt physical symptoms. Several reasons exist for this reduced investment, including a poor understanding of the mechanisms underlying impaired cognitive function, costly and long periods of development for these medications, disproportionately lower success rates, and a stigma associated with the medical treatment of mental illness. This paper will discuss these issues, review some of the successes resulting from research investment and discuss opportunities that should encourage increased research investment in cognitive disorders and their treatment.

Postoperative patient handovers are fraught with technical and communication errors and may negatively impact patient safety. We systematically reviewed the literature on handover of care from the operating room to postanesthesia or intensive care units and summarized process and communication recommendations based on these findings. From >500 papers, we identified 31 dealing with postoperative handovers. Twenty-four included recommendations for structuring the handover process or information transfer. Several recommendations were broadly supported, including (1) standardize processes (e.g., through the use of checklists and protocols); (2) complete urgent clinical tasks before the information transfer; (3) allow only patient-specific discussions during verbal handovers; (4) require that all relevant team members be present; and (5) provide training in team skills and communication. Only 4 of the studies developed an intervention and formally assessed its impact on different process measures. All 4 interventions improved metrics of effectiveness, efficiency, and perceived teamwork. Most of the papers were cross-sectional studies that identified barriers to safe, effective postoperative handovers including the incomplete transfer of information and other communication issues, inconsistent or incomplete teams, absent or inefficient execution of clinical tasks, and poor standardization. An association between poor-quality handovers and adverse events was also demonstrated. More innovative research is needed to define optimal patient handovers and to determine the effect of handover quality on patient outcomes.

Objective: To determine whether academic surgeons are satisfied with their salaries, and if they are willing to forego some compensation to support departmental academic endeavors., Background: Increasing financial constraints have led many academic surgery departments to rely on increasingly on clinical revenue generation for the cross-subsidization of research and teach missions., Methods: Members of 3 academic surgical societies (n = 3059) were surveyed on practice characteristics and attitudes about financial compensation. Univariate and multivariate logistic regression analyses were performed to identify determinants of salary satisfaction and willingness to forego compensation to support academic missions., Results: One thousand thirty-eight (33.9%) surgeons responded to our survey, 947 of whom maintain an academic practice. Of these academic surgeons, 49.7% expressed satisfaction with their compensation. Length of career, administrative responsibility for compensation and membership in the American Surgical Association or the Society of University Surgeons were predictive of salary satisfaction on univariate analysis. Frequent emergency call duty, increased clinical activity, and greater perceived difference between academic and private practice compensation were predictive of salary dissatisfaction. On multivariate analysis, increased clinical activity was inversely associated with both salary satisfaction (adjusted odds ratio [AOR], 0.77; [95% CI: 0.64, 0.94]; P = 0.009) and amount of compensation willingly killed for an academic practice (AOR, 0.71; [0.61, 0.83]; P < 0.0005)., Conclusions: Increasing reliance on clinical revenue to subsidize nonclinical academic missions is disaffecting many academic surgeons. Redefined mission priorities, enhanced nonfinancial rewards, utilization of nonclinical revenue sources (eg, philanthropy, grants), increased efficiency of business practices and/or redesign of fund flows may be necessary to sustain recruitment and retention of young academic surgeons.

Objective: To determine the incidence of potentially fraudulent (or "ghost") publications in applications to a general surgery residency program., Methods: Electronic Residency Application Services applications submitted in 2005 to the general surgery residency program were reviewed in an IRB-approved study. No identifiers were collected. Publications were checked against Medline, PubMed, ISI Web of Science, and Google. Nonverifiable publications were then submitted to the medical librarian for verification. Ghost publications were defined as journals, books, or meetings that cannot be verified; verified journals without the listed publication; or verified publications without an applicant author. Data analyses were performed using univariate and multivariate regression analysis for nonparametric data. A p value < 0.05 was considered significant., Results: Four hundred ninety-three applications were received. Thirty-one percent (150 of 493) of applicants listed a total of 596 publications, including 30 abstracts, 359 journal articles, and 207 chapters. Thirty-three percent (196 of 596) of the publications could not be verified: 7 abstracts, 177 journal articles, and 12 chapters. The distribution of ghost publications was skewed toward the journals subgroup (p < 0.001). Positive predictors of ghost publications were age and foreign medical school. The sole negative predictor was enrollment in a top-10 US research medical school., Conclusion: A disturbingly substantial fraction of publications listed on Electronic Residency Application Services applications cannot be verified. This might indicate a need for greater mentorship and oversight for medical school applicants. It is unknown whether this behavior predicts lack of integrity in other professional settings.

Objective: To determine if use of Model for End-Stage Liver Disease (MELD) scores to elective resections accurately predicts short-term morbidity or mortality., Summary Background Data: MELD scores have been validated in the setting of end-stage liver disease for patients awaiting transplantation or undergoing transvenous intrahepatic portosystemic shunt procedures. Its use in predicting outcomes after elective hepatic resection has not been evaluated., Methods: Records of 587 patients who underwent elective hepatic resection and were included in the National Surgical Quality Improvement Program Database were reviewed. MELD score, CTP score, Charlson Index of Comorbidity, American Society of Anesthesiology classification, and age were evaluated for their ability to predict short-term morbidity and mortality. Morbidity was defined as the development of one or more of the following complications: pulmonary edema or embolism, myocardial infarction, stroke, renal failure or insufficiency, pneumonia, deep venous thrombosis, bleeding, deep wound infection, reoperation, or hyperbilirubinemia. The analysis was repeated with patients divided according to their procedure and their primary diagnosis. Parametric or nonparametric analyses were performed as appropriate. Also, a new index was developed by dividing the patients into a development and a validation cohort, to predict morbidity and mortality in patients undergoing elective hepatic resection. ROC curves were also constructed for each of the primary indices., Results: CTP and ASA scores were superior in predicting outcome. Also, patients undergoing resection of primary malignancies had a higher rate of mortality but no difference in morbidity., Conclusion: MELD scores should not be used to predict outcomes in the setting of elective hepatic resection.

Transesophageal echocardiography is a crucial tool in intraoperative evaluation of newly implanted/repaired heart valves because suspected valvular malfunction needs to be identified and sometimes surgically corrected. Although color Doppler is often adequate in evaluating the expected regurgitant jets, as well as excluding pathologic paravalvular leaks, spectral Doppler techniques are the most commonly used methods for estimating transvalvular gradients in the operating room. However, these methods are subject to a variety of confounding factors, including subvalvular gradients and pressure recovery. Other methods of valve area estimation should also be used when evaluating a prostethic aortic valve, including the continuity equation and the left ventricular outflow tract/aortic valve velocity ratio.

Objective: To assess clinical safety of a low central venous pressure (CVP) fluid management strategy in patients undergoing liver transplantation., Design: Retrospective record review comparing 2 transplant centers, one using the low CVP method and the other using the normal CVP method., Setting: University-based, academic, tertiary care centers., Participants: Patients undergoing orthotopic cadaveric liver transplantation., Interventions: Each center practiced according to its own standard of care. Center 1 maintained an intraoperative CVP <5 mmHg using fluid restriction, nitroglycerin, forced diuresis, and morphine. If pressors were required to maintain systolic arterial pressure >90 mmHg, phenylephrine or norepinephrine was used. At center 2, CVP was kept 7 to 10 mmHg and mean arterial pressure >75 mmHg with minimal use of vasoactive drugs., Measurements and Main Results: Data collected included United Network for Organ Sharing status, surgical technique, intraoperative transfusion rate, preoperative and peak postoperative creatinine, time spent in intensive care unit and hospital, incidence of death, and postoperative need for hemodialysis. Principal findings include an increased rate of transfusion in the normal CVP group but increased rates of postoperative renal failure (elevated creatinine and more frequent need for dialysis) and 30-day mortality in the low CVP group., Conclusions: Despite success in lowering blood transfusion requirements in liver resection patients, a low CVP should be avoided in patients undergoing liver transplantation.

Background: Academic divisions of general surgery are facing ever-increasing financial pressures. Cost-cutting is a common approach to maintaining profitability, but strategies to increase revenue should not be ignored. One specific avenue for enhanced revenue generation in general surgery is that of coding for evaluation and management (E&M). Although this is the financial life-blood for many of the consultative services in departments of medicine, E&M coding is an often neglected and misunderstood component of surgical care., Study Design: The financial records for the Division of General Surgery were reviewed for the period of January 2001 to June 2003. Specifically, charges and receipts for inpatient procedures and hospital visits (CPT codes 99231, 99232, and 99233) were determined. The analysis was limited to surgeons with a primary clinical focus based at the University hospital rather than the neighboring community or Veteran's Affairs hospitals. In addition, ICD-9 and All Patient Refined Diagnosis Related Groups (APR-DRG) data were analyzed to determine the surgeon-specific number of inpatients and inpatient-days with more than one ICD-9 code or secondary ICD-9 codes, or both, or an APR-DRG severity of illness score of 2, 3, or 4. These categories were defined to determine the number of inpatient-days for which E&M coding could be billed for management of secondary medical diagnoses., Results: Analysis demonstrates that actual E&M charges were 40% to 47% of predicted minimums for E&M charges for the period under study. In theory, this result translates into an annual gain in receipts of 400,000 dollars to 600,000 dollars., Conclusions: We conclude that the ICD-9 and APR-DRG models may serve as benchmarks to determine the limits for E&M revenue stream, and E&M coding may represent an underutilized source of revenue among academic departments of surgery.

Background: New and innovative approaches must be used to rationally allocate scarce resources such as operating room time while simultaneously optimizing the associated financial return. In this article we use the technique of linear programming to optimize allocation of OR time among a group of surgeons based on professional fee generation., Study Design: For the period of December 1, 2000, to July 31, 2002, the following individualized data were obtained for the Division of General Surgery at Duke University Medical Center: allocated OR time (hours), case mix as determined by CPT codes, total OR time used, and normalized professional charges and receipts. Inpatient, outpatient, and emergency cases were included. The Solver linear programming routine in Microsoft Excel (Microsoft Corp.) was used to determine the optimal mix of surgical OR time allocation to maximize professional receipts., Results: Our model of optimized OR allocation would maximize weekly professional revenues at 237,523 US dollars, a potential increase of 15% over the historical value of 207,700 US dollars or an annualized increase of approximately 1.5 million US dollars., Conclusions: Our results suggest that mathematical modeling techniques used in operations research, management science, or decision science may rationally optimize OR allocation to maximize revenue or to minimize costs. These techniques may optimize allocation of scarce resources in the context of the goals specific to individual academic departments of surgery.

Advances in transplantation biology have greatly improved patient outcomes following transplant surgery. However, generalized immunosuppression remains the Achilles heel of modern transplantation surgery with its associated infectious and neoplastic morbidities. Tolerance remains the ultimate goal for the entire field. Although recent advances in transplant immunology suggest that tolerance may be achievable in the near future, the complex and redundant nature of the human immune system may not allow us to circumvent such a basic function as the recognition of nonself. In this paper, advances in transplant immunology are reviewed and their potential relevance to achieving the "Holy Grail" of transplantation are discussed.

Liver transplantation has become the procedure of choice for a wide variety of patients with end-stage liver disease. Perioperative morbidity and mortality have decreased dramatically over the past two decades, and superior graft and patient survival rates are now routine. Despite these advances, however, there remain several potentially lethal possibilities that may complicate the immediate postoperative period. Failure of the graft to regain any useful metabolic activity is known as primary nonfunction, and almost uniformly requires retransplantation for any hope of survival. Lesser degrees of immediate dysfunction require experienced clinical judgment as to the probability of sustaining long-term patient viability. Another potentially catastrophic development is thrombosis of the grafted hepatic artery. This is sometimes successfully managed by surgical reconstruction. It may develop immediately, or present insidiously much later. Thrombosis of the portal vein, while not usually fatal, can significantly complicate the immediate course, carrying with it a significant risk of sepsis. Close monitoring of patients in the period following liver transplantation is crucial, as prompt diagnosis and early intervention directly affects the patient's chances of survival.

The production of nitric oxide (NO) in response to endotoxin (LPS)-stimulation is associated with a myriad of NO-dependent regulatory functions. The study of NO-dependent genetic programs in the setting of endotoxin stimulation can be aided by determination of genes whose transcription is upregulated in the presence of NO and LPS. Using subtractive suppression hybridization analysis, we demonstrate that ANA-1 murine macrophages produce the CC class chemokines, monocyte chemoattractant protein-1 (JE/MCP-1) and macrophage inflammatory protein-related protein-1 (C10/MRP-1), in response to LPS-mediated nitric oxide (NO) production. MCP-1 and MRP-1 gene transcription and protein synthesis are upregulated in the setting of LPS-induced NO synthesis. NO alone is necessary but insufficient for induction of chemokine protein expression; an additional LPS-dependent signaling pathway is also required. This study suggests a novel mechanism by which NO induces chemokine expression and regulates the host inflammatory response to endotoxin.

The nature and chlorine reactivity of organic constituents in reclaimed water (tertiary-treated municipal wastewater) before, during, and after recharge into groundwater at the Montebello Forebay in Los Angeles County, CA, was the focus of this study. Dissolved organic matter (DOM) in reclaimed water from this site is primarily a mixture of aromatic sulfonates from anionic surfactant degradation, N-acetyl amino sugars and proteins from bacterial activity, and natural fulvic acid, whereas DOM from native groundwaters in the aquifer to which reclaimed water was recharged consists of natural fulvic acids. The hydrophilic neutral N-acetyl amino sugars that constitute 40% of the DOM in reclaimed water are removed during the first 3 m of vertical infiltration in the recharge basin. Groundwater age dating with 3H and 3He isotopes, and determinations of organic and inorganic C isotopes, enabled clear differentiation of recent recharged water from older native groundwater. Phenol structures in natural fulvic acids in DOM isolated from groundwater produced significant trihalomethanes (THM) and total organic halogen (TOX) yields upon chlorination, and these structures also were responsible for the enhanced SUVA and specific fluorescence characteristics relative to DOM in reclaimed water. Aromatic sulfonates and fulvic acids in reclaimed water DOM produced minimal THM and TOX yields.

In a system of endotoxin (LPS)-mediated NO production in ANA-1 murine macrophages, suppression subtractive hybridization was used to identify genes up-regulated by NO. Osteopontin (OPN), a secreted acidic phosphoprotein that binds to a cell surface RGD integrin-binding motif, was found to be differentially expressed in the presence of NO. OPN has been demonstrated to inhibit NO production in a variety of cell types. Northern blot and nuclear run-on analyses demonstrated that OPN mRNA levels and gene transcription were significantly increased in the presence of LPS-induced NO synthesis. Transient transfection of an OPN promoter-luciferase reporter plasmid construct showed that promoter activity is increased in the presence of LPS and NO. Immunoblot analysis showed that OPN protein is secreted into the extracellular fluid. Similar results were noted with an alternative cell system, RAW 264.7 macrophages, and alternative inducers of NO synthesis, IFN-gamma and IL-1beta. In the presence of GRGDSP, a hexapeptide that blocks binding of RGD-containing proteins to cell surface integrins, NO production is significantly increased in the presence of LPS stimulation. These data suggest a unique trans-regulatory mechanism in which LPS-induced NO synthesis feedback regulates itself through up-regulation of OPN promoter activity and gene transcription.

Portal hypertension is associated with a wide range of pulmonary pathophysiologies, ranging from portopulmonary hypertension to hepatopulmonary syndrome. Although the clinical and pathological features of pulmonary dysfunction in this setting have been extensively characterized, the underlying biology is not well understood. Specifically, the role of mediators that regulate mesenteric vascular hemodynamics in portal hypertension, such as nitric oxide and endothelin, have not been studied in the lung. Using a rat model of prehepatic portal hypertension with preserved hepatic function, we examined pulmonary elaboration of endothelial nitric oxide synthase (NOS), inducible NOS, heme oxygenase- 1 (HO-1), heme oxygenase-2 (HO-2), endothelin-1 mRNA, and protein. In comparison to sham controls, portal hypertensive animals exhibited significantly increased pulmonary iNOS and HO-1 mRNA and protein. Cyclic GMP was significantly increased in portal hypertensive lung tissue, suggesting activation of guanylyl cyclase by the endproducts of iNOS and/or HO-1 activity. Using immunohistochemical analysis, iNOS expression was localized to the vascular endothelium, while HO-1 localized to bronchiolar epithelium and macrophages. These results suggest that production of nitric oxide and carbon monoxide may contribute to the pulmonary pathology associated with portal hypertension.

NO can regulate specific cellular functions by altering transcriptional programs and protein reactivity. With respect to global cellular processes, NO has also been demonstrated to inhibit total protein synthesis and cell proliferation. The underlying mechanisms are unknown. In a system of ANA-1 murine macrophages, iNOS expression and NO production were induced by exposure to endotoxin (LPS). In selected instances, cells were exposed to an exogenous NO donor, S-nitroso-N-acetylpenicillamine or a substrate inhibitor of NO synthesis. Cellular exposure to NO, from both endogenous and exogenous sources, was associated with a significant time-dependent decrease in total protein synthesis and cell proliferation. Gene transcription was unaltered. In parallel with decreased protein synthesis, cells exhibited a distinctive cleavage pattern of 28S and 18S rRNA that were the result of two distinct cuts in both 28S and 18S rRNA. Total levels of intact 28S rRNA, 18S rRNA, and the composite 60S ribosome were significantly decreased in the setting of cell exposure to NO. Finally, 60S ribosome-associated peptidyl transferase activity, a key enzyme for peptide chain elongation, was also significantly decreased. Our data suggest that NO-mediated cleavage of 28S and 18S rRNA results in decreased 60S ribosome associated peptidyl transferase activity and inhibition of total protein synthesis.

Background: Portopulmonary hypertension is a known complication in the liver transplant candidate. Intravenous epoprostenol has been demonstrated to decrease pulmonary artery pressures and possibly remodel right ventricle geometry., Methods: In this report, we document the efficacy of inhaled aerosolized epoprostenol in a patient with portopulmonary hypertension. The effect was of rapid onset and offset., Results: After 10 min of delivery, mean pulmonary artery pressure decreased 26%; cardiac output increased by 22%; pulmonary vascular resistance decreased by 42%; and the transpulmonary gradient decreased by 29%. There were no untoward side effects., Conclusion: The inhaled route of delivery of epoprostenol is potential alternative for the acute therapy of portpulmonary hypertension.

Inhaled prostacyclin (PGI(2)) can be used as an effective pulmonary vasodilator intraoperatively to treat pulmonary hypertension and impending right ventricular failure.

Background & Aims: Exposure to oxidative stress, as in states of shock, ischemia-reperfusion injury, or sepsis, commonly initiates a complex cellular cascade of interlocking redox modulatory systems that detoxify electrophiles. In interleukin 1beta (IL-1beta)-treated rat hepatocytes, we have previously demonstrated that inducible nitric oxide synthase (iNOS) protein expression, steady-state iNOS messenger RNA (mRNA) levels, and NO synthesis are increased by oxidative stress induced by superoxide. The effect of hepatocellular redox state upon iNOS gene transcription has not been previously studied., Methods: Using rat hepatocytes in primary culture, iNOS gene transcription was induced by IL-1beta. Oxidative stress was mediated by 1,2,3-benzenetriol (BZT), an autocatalytic source of superoxide. Nuclear run-on assays and transient transfection assays using the rat hepatocyte iNOS full-length promoter and deletion constructs were designed to isolate a cis-acting regulatory element. Specificity was confirmed by site-directed mutagenesis. Gel shift analysis determined the presence of a corresponding trans-acting regulatory factor., Results: In IL-1beta-treated cells, BZT increased iNOS gene transcription without altering mRNA half-life. An antioxidant-responsive element (ARE) was found in the iNOS promoter at base pair -1347, which conferred redox sensitivity. Gel shift analysis identified a corresponding nuclear protein capable of binding to ARE in IL-1beta- and BZT-treated rat hepatocytes., Conclusions: An ARE in the rat hepatocyte iNOS promoter confers redox sensitivity and augments IL-1beta-mediated iNOS gene and protein expression in the setting of superoxide treatment.

On the basis of previous work demonstrating nitric oxide (NO)-mediated inhibition of nuclear factor-kappaB (NF-kappaB) DNA binding, we hypothesized that NO downregulates NF-kappaB-dependent interleukin-1beta (IL-1beta) production in an ANA-1 macrophage model of lipopolysaccharide (LPS) stimulation. In the presence of LPS (100 ng/ml), levels of IL-1beta protein and mRNA were significantly upregulated with NO synthase inhibition. Using nuclear run-on analysis and transient transfection studies, IL-1beta gene transcription and IL-1beta promoter activity were also found to be increased with inhibition of NO production. Parallel transfection studies using an NF-kappaB long terminal repeat-reporter plasmid exhibited similar findings, suggesting an NO-mediated effect on NF-kappaB activity. Gel shift studies showed that LPS-associated NF-kappaB DNA binding was increased, both in the setting of NO synthase inhibition and in a reducing environment. Repletion of NO by addition of an S-nitrosothiol restored IL-1beta protein synthesis, mRNA levels, gene transcription, promoter activity, and NF-kappaB DNA binding to levels noted in the presence of LPS alone. Our studies indicate that NO may regulate LPS-associated inflammation by downregulating IL-1beta gene transcription through S-nitrosation of NF-kappaB.

Background: The purpose of this study was to define the redox sensitive cis-acting transcriptional mechanisms that regulate inducible nitric oxide synthase (iNOS) promoter function in the hepatocyte., Methods: Clonal deletion constructs of the rat hepatocyte iNOS promoter (Genbank X95629; 1845 base pair)-reporter plasmid were transiently transfected into HepG2 cells treated with IL-1 beta and IL-1 beta + hydrogen peroxide., Results: A segment of the promoter upstream from nucleotide -1126 was associated with redox-sensitive augmentation of promoter activity. Site-directed mutagenesis of 2 antioxidant response elements (AREs) was combined with transfection analysis to demonstrate that mutation of the ARE at nt-1347 ablated oxidant stress-mediated activation of the iNOS promoter., Conclusions: This ARE conveys the redox-sensitive response of the rat iNOS promoter. Hepatocyte iNOS expression is a novel and, as yet, poorly described antioxidant mechanism that is cytokine and redox sensitive and that plays a pleuripotent regulatory role in hepatocellular function in the face of sepsis and shock.

The management of the liver transplant (OLT) candidate with portopulmonary hypertension (PPHTN) has dramatically changed in the past 3 years. Careful preoperative evaluation with functional characterization of right ventricular function plays a critical role. The pulmonary vascular response to epoprostenol infusion serves as a deciding factor for OLT candidacy. Careful perioperative attention to avoid right ventricular failure from acutely elevated pulmonary artery pressures or sudden increases in right ventricular preload is a key physiologic tenet of management. With increased surgical expertise, anesthetic sophistication, and availability of epoprostenol, PPHTN is no longer considered an absolute contraindication for OLT.

Nitric oxide (NO) regulates cellular function, in part, by S-nitrosylating active site thiol groups of proteins. Ex vivo S-nitrosylation of NF-kappa B p50 significantly decreases its capacity for DNA binding. To determine the cellular relevance of this observation, we utilized the ANA-l murine macrophage model of endotoxin (LPS)-mediated NO synthesis. In selected instances, the NO synthase inhibitor, L-arginine methyl ester (L-NAME; 100 microM), or the NO donor, S-nitroso-N-acetylcysteine (SNAC; 100 microM), was added. In contrast to that of LPS cells, nuclear extracts from LPS + L-NAME cells demonstrated increased NF-kappa B DNA binding on gel shift analysis. Addition of SNAC to LPS + L-NAME cells restored binding to a level equivalent to that of LPS cells. Spectrophotometric analysis of NF-kappa B p50 immunoprecipitates demonstrated S-NO bonds exclusively in LPS cells; these p50 protein isolates retained the same DNA binding characteristics as that of the nuclear extracts. Transfection assays utilizing NF-kappa B-dependent promoter-reporter constructs demonstrated increased activity in LPS + L-NAME cells compared with LPS cells; nuclear run-on assays confirmed increased transcription of the corresponding genes. These results suggest that LPS-mediated NO synthesis is associated with S-nitrosylation of NF-kappa B p50 and inhibition of NF-kappa B-dependent DNA binding, promoter activity, and gene transcription. We conclude that NO can regulate gene transcription by S-nitrosylation of NF-kappa B.

Background: Nitric oxide (NO) regulates a variety of cellular functions. One mechanism by which NO may exert its influence is through formation of S-nitrosothiols at critical thiol residues in protein-active sites, including those of nuclear protein transcription factors., Methods: NF-kappa B p50 and AP-1 c-jun were S-nitrosylated in the presence of acidic NaNO2. Wild-type protein and protein subjected to nitrosylating conditions in the absence of NaNO2 served as controls. Confirmatory evidence for S-nitrosothiol bond formation was obtained by ultraviolet-visible spectrophotometry with the absorption maximum for S-NO bonds at approximately 320 to 360 nm. With consensus oligonucleotide probes, gel-shift analysis was used to examine DNA binding characteristics., Results: In the case of NF-kappa B p50, S-nitrosylation resulted in significantly decreased DNA binding. In contrast, S-nitrosylation did not alter c-jun DNA binding. The S-nitrosylating conditions themselves did not alter p50 or c-jun DNA binding. Quantitative analysis was performed according to the Scatchard plot technique to generate the respective dissociation constants. S-nitrosylated p50 was associated with a fourfold greater dissociation constant than that of the wild-type p50., Conclusions: S-nitrosylation of transcription factors may be one mechanism by which NO may selectively regulate gene transcription.

The multiple interlocking regulatory mechanisms that underlie induction of hepatocyte inducible nitric oxide synthase (iNOS) expression are largely unknown. Although previous work has indicated the requirement for multiple proinflammatory cytokines to induce hepatocyte NO production, investigators have recently shown that interleukin-1beta (IL-1beta) alone can initiate iNOS expression. In contrast, interferon gamma (IFN-gamma) serves as the sole initiating factor in other cell systems. On the basis of the known ability of IL-1beta to induce transcription and translation of the IFN family of genes, we hypothesized that IL-1beta-mediated hepatocyte expression of iNOS is dependent on endogenous IFN-gamma synthesis. In a system of rat hepatocytes in primary culture, IL-1beta induced production of both NO and IFN-gamma. Using in situ hybridization and immunoblot analysis, IFN-gamma messenger RNA (mRNA) and protein were detected in hepatocytes exposed to IL-1beta. Inhibition of NO synthesis using the competitive substrate inhibitor N-monomethyl-L-arginine (100 micromol/L) did not alter the extent of IL-1beta-mediated IFN-gamma synthesis. In contrast, anti-IFN-gamma antibody or inhibition of IFN-gamma mRNA translation by addition of antisense IFN-gamma oligodeoxynucleotide probes resulted in undetectable levels of NO metabolites and iNOS protein. Repletion of IFN-gamma to the system restored NO production to levels noted in the presence of IL-1beta alone. Transient transfection analysis using a rat hepatocyte iNOS promoter-reporter gene plasmid construct showed that IL-1beta-induced promoter activation was abolished in the presence of anti-IFN-gamma or antisense IFN-gamma. Again, addition of IFN-gamma to the system restored activity of the iNOS promoter. Parallel experiments examining IL-1beta-mediated endogenous hepatocyte IL-1beta and TNF-alpha synthesis indicated no role for these cytokines in the induction of iNOS expression by IL-1beta. It is concluded that IL-1beta-mediated hepatocyte synthesis of NO is dependent on the simultaneous endogenous synthesis of IFN-gamma.

The possible testicular toxicity of Andrographis paniculata, Nees (Acanthaceae) standardized dried extract was evaluated in male Sprague Dawley rats for 60 days. No testicular toxicity was found with the treatment of 20, 200 and 1000 mg/kg during 60 days as evaluated by reproductive organ weight, testicular histology, ultrastructural analysis of Leydig cells and testosterone levels after 60 days of treatment. It is concluded that Andrographis paniculata dried extract did not produce subchronic testicular toxicity effect in male rats.

Nitric oxide (NO) regulates a wide variety of cellular functions, in part, by formation of S-NO bonds at critical active site thiol groups within proteins, including transcription factors. Previous studies have qualitatively demonstrated that S-nitrosothiol formation can alter transcription factor binding to the DNA recognition site. To more precisely define the effect of S-nitrosylation on transcription factor binding, the equilibrium binding constant was derived for S-nitrosylated NF-kappa B p50 (S-NO-p50) in a cell free system utilizing gel shift assays. Binding of NF-kappa B p50 subjected to the nitrosylation conditions in the absence of NaNO2 (C-p50-2) was not different from that of wild type NF-kappa B (C-p50-1). The extent of S-NO-p50 binding to its DNA target sequence was significantly decreased in comparison to that noted with C-p50-1 and C-p50-2. The binding constant was derived for each of the NF-kappa B variants: C-p50-1 = 1.01 x 10(10) M(-1); C-p50-2 = 0.92 x 10(10) M(-1); and S-NO-p50 = 0.28 x 10(10) M(-1). These data indicate that S-nitrosylation of p50 decreases its affinity for the target DNA sequence by four-fold.

Endotoxin-mediated macrophage synthesis of nitric oxide (NO) is associated with immune effector function, intercellular communication, leukocyte adhesion, vascular integrity, and neurotransmission. However, little is known of the cellular receptor and signal transduction pathway by which endotoxin induces NO production. With the use of a model of ANA-1 murine macrophages, we stimulated NO production by incubation with increasing concentrations of endotoxin and 5% fetal calf serum. In selected instances, the anti-CD14 antibody, ED9, was added. Endotoxin-mediated NO synthesis was dependent on CD14 function and the presence of an additional serum factor. Endotoxin treatment increased plasma membrane GTPase activity and 35S-labeled guanosine 5'-O-(3-thiotriphosphate) ([35S]GTP gamma S) binding. Conversely, coincubation of cells with endotoxin and the heterotrimeric G protein inhibitors, suramin and guanosine 5'-O-(2-thiodiphosphate) trilithium salt, was associated with decreased NO synthesis, plasma membrane GTPase activity, and [35S]GTP gamma S binding. Blockade of CD14 or G protein function was associated with ablation of endotoxin-mediated inducible NO synthase (iNOS) protein expression, iNOS mRNA levels, and iNOS gene transcription, as determined by immunoblot, reverse transcriptase-polymerase chain reaction, and nuclear run-on analyses, respectively. These results indicate that endotoxin-mediated NO synthesis is a CD14-heterotrimeric G protein-dependent process.

Background: Nitric oxide (NO) is a ubiquitous multifunctional free radical produced during sepsis, shock, reperfusion injury, and allograft rejection. Many studies are presently evaluating the functional roles of NO production in these settings. However, the signal transduction mechanisms underlying initiation of NO production are largely unknown. This study defines the cell surface receptor proteins that mediate endotoxin-induced NO synthesis in ANA-1 murine macrophages., Methods: Endotoxin (LPS, 10 micrograms/ml) was added to ANA-1 macrophages to induce NO synthesis. In selected instances guanosine 5'-O-(2-thiodiphosphate)-trilithium salt (GOTP), pertussis toxin, cholera toxin, or suramin were added as inhibitors of specific subclasses of heterotrimeric G proteins. Calphostin was added as a protein kinase C inhibitor, and ET-OCH3 was added as a phospholipase C-beta inhibitor. NO release was quantified by measurement of the NO metabolite, nitrite. Membrane guanosine triphosphatase (GTPase) activity was also analyzed. Steady-state levels of inducible nitric oxide synthase (iNOS) mRNA were determined by using reverse transcription-polymerase chain reaction analysis., Results: Inhibition of G protein function by suramin or GOTP significantly decreased synthesis of NO and expression of iNOS mRNA. Pertussis and cholera toxin did not alter NO synthesis, suggesting that the Gi and Gs classes are not involved. Inhibition of protein kinase C or upstream phospholipase C-beta activity decreased NO synthesis, implicating the Gq class of heterotrimeric G proteins., Conclusions: In ANA-1 macrophages, endotoxin-mediated NO synthesis is dependent on heterotrimeric Gq protein-phospholipase C-beta-protein kinase C signal transduction.