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BACKGROUND: Low procedural complication rates, barriers to access, and patient preference have encouraged the development of percutaneous coronary intervention (PCI) programs at centers that are often closer to home but without on-site cardiac surgical capability. OBJECTIVES: We compared clinical and economic outcomes associated with performing low-risk elective PCI at a community hospital without on-site cardiac surgery with those obtained at a more remote tertiary care center with on-site cardiac surgery. DESIGN AND MEASURES: We matched 257 patients undergoing low-risk, elective PCI at a community hospital (Immanuel St. Joseph's Hospital [ISJ] between January 27, 2000, and July 31, 2002) to 514 PCI patients treated at a tertiary care hospital (Saint Marys Hospital [SMH] between January 27, 2000, and April 30, 2002) based on clinical and lesion criteria. Clinical outcomes (in-hospital procedural success and target vessel failure during long-term follow up) and economic outcomes (direct medical costs, billed charges, and hospital length of stay [LOS]) were compared between groups. The Mayo Clinic PCI Registry (containing clinical, angiographic, and follow-up data) and administrative data were used in matching and outcomes assessment. RESULTS: Procedural success was achieved more often among ISJ-treated patients (99% vs. 95%; P = 0.02); however, no difference in target vessel failure rates was observed during a median follow-up time of 3.1 years (estimated 1-year event rate: 15.2% vs. 14.8%; P = 0.46). ISJ-treated patients incurred, on average, $3024 more in estimated total costs ($13,771 vs. $10,746; P < 0.001) and $6084 more in billed charges (P < 0.001), but incurred similar LOS post procedure (1.53 days). CONCLUSIONS: Similar clinical outcomes were achieved at a community hospital without on-site cardiac surgery but at significantly increased direct medical cost. Patients, providers, hospitals, payers, and policymakers should consider whether the benefits associated with locally provided specialized cardiovascular services warrant this additional cost. [ABSTRACT FROM AUTHOR]

Background: Older adults surviving critical illness often experience new or worsening functional impairments. Modifiable positive psychological constructs such as resilience may mitigate post-intensive care morbidity., Research Question: Is pre-ICU resilience associated with: (1) post-ICU survival; (2) the drop in functional independence during the ICU stay; or (3) the trend in predicted independence before vs after the ICU stay?, Study Design and Methods: This retrospective cohort study was performed by using Medicare-linked Health and Retirement Study surveys from 2006 to 2018. Older adults aged ≥ 65 years admitted to an ICU were included. Resilience was calculated prior to ICU admission. The resilience measure was defined from the Simplified Resilience Score, which was previously adapted and validated for the Health and Retirement Study. Resilience was scored by using the Leave-Behind survey normalized to a scale from 0 (lowest resilience) to 12 (highest resilience). Outcomes were survival and probability of functional independence. Survival was modeled by using Gompertz models and independence using joint survival models adjusting for sociodemographic and clinical variables. Average marginal effects were estimated to determine independence probabilities., Results: Across 3,409 patients aged ≥ 65 years old admitted to ICUs, preexisting frailty (30.5%) and cognitive impairment (24.3%) were common. Most patients were previously independent (82.7%). Mechanical ventilation occurred in 14.8% and sepsis in 43.2%. Those in the highest resilience group (vs lowest resilience) had a lower risk of post-ICU mortality (adjusted hazard ratio, 0.81; 95% CI, 0.70-0.94). Higher resilience was associated with greater likelihood of post-ICU functional independence (estimated probability of functional independence 5 years after ICU discharge in highest-to-lowest resilience groups (adjusted hazard ratio [95% CI]): 0.53 (0.33-0.74), 0.47 (0.26-0.68), 0.49 (0.28-0.70), and 0.36 (0.17-0.55); P < .01. Resilience was not associated with a difference in the drop in independence during the ICU stay or a difference in the pre-ICU vs post-ICU trend in predicted independence ., Interpretation: ICU survivors with higher resilience had increased rates of survival and functional independence, although the slope of functional decline before vs after the ICU stay did not differ according to resilience group., Competing Interests: Financial/Nonfinancial Disclosures None declared., (Published by Elsevier Inc.)

Background: Social constructs like race can affect how patients are perceived and impact care. This study investigated whether mentions of race in notes for critically ill patients differed according to patients' race., Methods: This retrospective cohort study included intensive care unit notes for adults (≥18 years old) admitted to any of 6 intensive care units at University of California, San Francisco, from 2012 through 2020. Notes were linked to National Provider Identifier records to obtain note writer characteristics. Logistic regression analysis with robust SEs clustered on note writers was adjusted for patient-, note- and clinician-level characteristics. Any race or ethnicity mention was the outcome of interest., Results: Among 5573 patients with 292 457 notes by 9742 unique note writers, 3225 patients (57.9%) self-reported their race as White, 997 (17.9%) as Asian, 860 (15.4%) as Latinx, and 491 (8.8%) as Black. Note writers documented race/ethnicity for 20.8% of Black, 10.9% of Latinx, 9.1% of White, and 4.4% of Asian patients. Black patients were more likely than White patients to have race mentioned in notes (adjusted odds ratio, 2.05 [95% CI, 1.49-2.82])., Conclusions: Black patients were more than twice as likely as White patients to have race mentioned in notes. Note language containing information on social constructs has consequences for clinicians and patients reading notes and for algorithms trained on clinical notes., (©2024 American Association of Critical-Care Nurses.)

Background: A metaphor conceptualizes one, typically abstract, experience in terms of another, more concrete, experience with the goal of making it easier to understand. Although combat metaphors have been well described in some health contexts, they have not been well characterized in the setting of critical illness., Research Question: How do clinicians use combat metaphors when describing critically ill patients and families in the electronic health record?, Study Design and Methods: We included notes written about patients aged 18 years or older admitted to ICUs within a large hospital system from 2012 through 2020. We developed a lexicon of combat words and isolated note segments that contained any combat mentions. Combat mentions were defined systematically as a metaphor or not across two coders. Among combat metaphors, we used a grounded theory approach to construct a conceptual framework around their use., Results: Across 6,404 combat-related mentions, 5,970 were defined as metaphors (Cohen κ, 0.84). The most common metaphors were "bout" (26.2% of isolated segments), "combat" (18.5%), "confront" (17.8%), and "struggle" (17.5%). We present a conceptual framework highlighting how combat metaphors can present as identity ("mom is a fighter") and process constructs ("struggling to breathe"). Identity constructs usually were framed around: (1) hope, (2) internal strength, (3) contextualization of current illness based on prior experiences, or (4) a combination thereof. Process constructs were used to describe: (1) "fighting for" (eg, working toward) a goal, (2) "fighting against" an unwanted force, or (3) experiencing internal turmoil., Interpretation: We provide a novel conceptual framework around the use of combat metaphors in the ICU. Further studies are needed to understand intentionality behind their use and how they impact clinician behaviors and patient and caregiver emotional responses., Competing Interests: Financial/Nonfinancial Disclosures None declared., (Published by Elsevier Inc.)

Background: Heart failure affects thousands of patients annually, often resulting in hospitalization, emergency room visits, and decreased quality of life. The scientific evidence indicates that disease management programs using a multidisciplinary approach improve outcomes for heart failure patients., Aim: The overarching aim of this evidence implementation project was to establish a disease management program for heart failure patients. Specifically, the project sought to promote compliance with best practices for the early identification of heart failure exacerbation symptoms to prevent emergency room visits and hospitalizations, thereby reducing morbidity and mortality., Methods: This project was guided by the JBI Evidence Implementation Framework, which is grounded in an audit, feedback, and re-audit strategy. A baseline audit was conducted, revealing the need for a heart failure disease management program. A policy was developed to implement a disease management program and virtual relationships were established to create a multidisciplinary team. A follow-up audit was conducted to determine whether the implemented interventions closed the gap in practice identified by the baseline audit., Results: The baseline audit revealed 0% compliance with best practices for the management of patients with heart failure, while the follow-up audit revealed 93.3% compliance., Conclusions: This project enhanced best practices by implementing a protocol in a rural health clinic to ensure that all heart failure patients were enrolled in a disease management program. Recommendations include using the electronic health record to quickly identify heart failure patients and their status in a disease management program. Chart audits should be performed every 6 months to ensure the program's sustainability and to determine heart failure patients' enrollment status., Spanish Abstract: http://links.lww.com/IJEBH/A270., Competing Interests: The authors declare no conflicts of interest., (Copyright © 2024 JBI. Unauthorized reproduction of this article is prohibited.)

Objectives: To examine trends in the prevalence of multiorgan dysfunction (MODS), utilization of multi-organ support (MOS), and mortality among patients undergoing cardiac surgery with MODS who received MOS in the United States., Design: Retrospective cohort study., Setting: 183 hospitals in the Premier Healthcare Database., Participants: Adults ≥18 years old undergoing high-risk elective or non-elective cardiac surgery., Interventions: none., Measurements and Main Results: The exposure was time (consecutive calendar quarters) January 2008 and June 2018. We analyzed hospital data using day-stamped hospital billing codes and diagnosis and procedure codes to assess MODS prevalence, MOS utilization, and mortality. Among 129,102 elective and 136,190 non-elective high-risk cardiac surgical cases across 183 hospitals, 10,001 (7.7%) and 21,556 (15.8%) of patients developed MODS, respectively. Among patients who experienced MODS, 2,181 (22%) of elective and 5,425 (25%) of non-elective cardiac surgical cases utilized MOS. From 2008-2018, MODS increased in both high-risk elective and non-elective cardiac surgical cases. Similarly, MOS increased in both high-risk elective and non-elective cardiac surgical cases. As a component of MOS, mechanical circulatory support (MCS) increased over time. Over the study period, risk-adjusted mortality, in patients who developed MODS receiving MOS, increased in high-risk non-elective cardiac surgery and decreased in high-risk elective cardiac surgery, despite increasing MODS prevalence and MOS utilization (p<0.001)., Conclusions: Among patients undergoing high-risk cardiac surgery in the United States, MODS prevalence and MOS utilization (including MCS) increased over time. Risk-adjusted mortality trends differed in elective and non-elective cardiac surgery. Further research is necessary to optimize outcomes among patients undergoing high-risk cardiac surgery., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: JC reports consulting fees from Teleflex, but there are no other conflicts of interest to report., (Published by Elsevier Inc.)

Background: Language in nonmedical data sets is known to transmit human-like biases when used in natural language processing (NLP) algorithms that can reinforce disparities. It is unclear if NLP algorithms of medical notes could lead to similar transmissions of biases., Research Question: Can we identify implicit bias in clinical notes, and are biases stable across time and geography?, Study Design and Methods: To determine whether different racial and ethnic descriptors are similar contextually to stigmatizing language in ICU notes and whether these relationships are stable across time and geography, we identified notes on critically ill adults admitted to the University of California, San Francisco (UCSF), from 2012 through 2022 and to Beth Israel Deaconess Hospital (BIDMC) from 2001 through 2012. Because word meaning is derived largely from context, we trained unsupervised word-embedding algorithms to measure the similarity (cosine similarity) quantitatively of the context between a racial or ethnic descriptor (eg, African-American) and a stigmatizing target word (eg, nonco-operative) or group of words (violence, passivity, noncompliance, nonadherence)., Results: In UCSF notes, Black descriptors were less likely to be similar contextually to violent words compared with White descriptors. Contrastingly, in BIDMC notes, Black descriptors were more likely to be similar contextually to violent words compared with White descriptors. The UCSF data set also showed that Black descriptors were more similar contextually to passivity and noncompliance words compared with Latinx descriptors., Interpretation: Implicit bias is identifiable in ICU notes. Racial and ethnic group descriptors carry different contextual relationships to stigmatizing words, depending on when and where notes were written. Because NLP models seem able to transmit implicit bias from training data, use of NLP algorithms in clinical prediction could reinforce disparities. Active debiasing strategies may be necessary to achieve algorithmic fairness when using language models in clinical research., Competing Interests: Financial/Nonfinancial Disclosures None declared., (Published by Elsevier Inc.)

The need to integrate palliative care (PC) training into surgical education has been increasingly recognized. Our aim is to describe a set of PC educational strategies, with a range of requisite resources, time, and prior expertise, to provide options that surgical educators can tailor for different programs. Each of these strategies has been successfully employed individually or in some combination at our institutions, and components can be generalized to other training programs. Asynchronous and individually paced PC training can be provided using existing resources published by the American College of Surgeons and upcoming SCORE curriculum modules. A multiyear PC curriculum, with didactic components of increasing complexity for more advanced residents, can be applied based on available time in the didactic schedule and local expertise. Simulation-based training in PC skills can be developed to provide objective competency-based training. Finally, a dedicated rotation on a surgical palliative care service can provide the most immersive experience with steps toward clinical entrustment of PC skills for trainees., (Copyright © 2023 The Author(s). Published by Elsevier Inc. All rights reserved.)

Objectives: To develop proof-of-concept algorithms using alternative approaches to capture provider sentiment in ICU notes., Design: Retrospective observational cohort study., Setting: The Multiparameter Intelligent Monitoring of Intensive Care III (MIMIC-III) and the University of California, San Francisco (UCSF) deidentified notes databases., Patients: Adult (≥18 yr old) patients admitted to the ICU., Measurements and Main Results: We developed two sentiment models: 1) a keywords-based approach using a consensus-based clinical sentiment lexicon comprised of 72 positive and 103 negative phrases, including negations and 2) a Decoding-enhanced Bidirectional Encoder Representations from Transformers with disentangled attention-v3-based deep learning model (keywords-independent) trained on clinical sentiment labels. We applied the models to 198,944 notes across 52,997 ICU admissions in the MIMIC-III database. Analyses were replicated on an external sample of patients admitted to a UCSF ICU from 2018 to 2019. We also labeled sentiment in 1,493 note fragments and compared the predictive accuracy of our tools to three popular sentiment classifiers. Clinical sentiment terms were found in 99% of patient visits across 88% of notes. Our two sentiment tools were substantially more predictive (Spearman correlations of 0.62-0.84, p values < 0.00001) of labeled sentiment compared with general language algorithms (0.28-0.46)., Conclusion: Our exploratory healthcare-specific sentiment models can more accurately detect positivity and negativity in clinical notes compared with general sentiment tools not designed for clinical usage., (Copyright © 2023 The Authors. Published by Wolters Kluwer Health, Inc. on behalf of the Society of Critical Care Medicine.)

Background: Older adults are increasingly admitted to the ICU, and those with disabilities, dementia, frailty, and multimorbidity are vulnerable to adverse outcomes. Little is known about how pre-existing geriatric conditions have changed over time., Research Question: How have changes in disability, dementia, frailty, and multimorbidity in older adults admitted to the ICU changed from 1998 through 2015?, Study Design and Methods: Medicare-linked Health and Retirement Survey (HRS) data identifying patients 65 years of age and older admitted to an ICU between 1998 and 2015. ICU admission was the unit of analysis. Year of ICU admission was the exposure. Disability, dementia, frailty, and multimorbidity were identified based on responses to HRS surveys before ICU admission. Disability represented the need for assistance with ≥ 1 activity of daily living. Dementia used cognitive and functional measures. Frailty included deficits in ≥ 2 domains (physical, nutritive, cognitive, or sensory function). Multimorbidity represented ≥ 3 self-reported chronic diseases. Time trends in geriatric conditions were modeled as a function of year of ICU admission and were adjusted for age, sex, race or ethnicity, and proxy interview status., Results: Across 6,084 ICU patients, age at admission increased from 77.6 years (95% CI, 76.7-78.4 years) in 1998 to 78.7 years (95% CI, 77.5-79.8 years) in 2015 (P < .001 for trend). The adjusted proportion of ICU admissions with pre-existing disability rose from 15.5% (95% CI, 12.1%-18.8%) in 1998 to 24.0% (95% CI, 18.5%-29.6%) in 2015 (P = .001). Rates of dementia did not change significantly (P = .21). Frailty increased from 36.6% (95% CI, 30.9%-42.3%) in 1998 to 45.0% (95% CI, 39.7%-50.2%) in 2015 (P = .04); multimorbidity rose from 54.4% (95% CI, 49.2%-59.7%) in 1998 to 71.8% (95% CI, 66.3%-77.2%) in 2015 (P < .001)., Interpretation: Rates of pre-existing disability, frailty, and multimorbidity in older adults admitted to ICUs increased over time. Geriatric principles need to be deeply integrated into the ICU setting., (Published by Elsevier Inc.)

Context: Palliative care (PC) benefits critically ill patients but remains underutilized. Important to developing interventions to overcome barriers to PC in the ICU and address PC needs of ICU patients is to understand how, when, and for which patients PC is provided in the ICU., Objectives: Compare characteristics of specialty PC consultations in the ICU to those on medical-surgical wards., Methods: Retrospective analysis of national Palliative Care Quality Network data for hospitalized patients receiving specialty PC consultation January 1, 2013 to December 31, 2019 in ICU or medical-surgical setting. 98 inpatient PC teams in 16 states contributed data. Measures and outcomes included patient characteristics, consultation features, process metrics and patient outcomes. Mixed effects multivariable logistic regression was used to compare ICU and medical-surgical units., Results: Of 102,597 patients 63,082 were in medical-surgical units and 39,515 ICU. ICU patients were younger and more likely to have non-cancer diagnoses (all P < 0.001). While fewer ICU patients were able to report symptoms, most patients in both groups reported improved symptoms. ICU patients were more likely to have consultation requests for GOC, comfort care, and withdrawal of interventions and less likely for pain and/or symptoms (OR-all P < 0.001). ICU patients were less often discharged alive., Conclusion: ICU patients receiving PC consultation are more likely to have non-cancer diagnoses and less likely able to communicate. Although symptom management and GOC are standard parts of ICU care, specialty PC in the ICU is often engaged for these issues and results in improved symptoms, suggesting routine interventions and consultation targeting these needs could improve care., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)

Global climate change continues to impact fish habitat quality and biodiversity, especially in regard to the dynamics of invasive non-native species. Using individual aquaria and an open channel flume, this study evaluated the effects of water temperature, flow velocity and turbulence interactions on swimming performance of two lentic, invasive non-native fish in the UK, pumpkinseed ( Lepomis gibbosus ) and topmouth gudgeon ( Pseudorasbora parva ). Burst and sustained swimming tests were conducted at 15, 20 and 25°C. Acoustic Doppler velocimetry was used to measure the flume hydrodynamic flow characteristics. Both L. gibbosus and P. parva occupied the near-bed regions of the flume, conserving energy and seeking refuge in the low mean velocities flow areas despite the relatively elevated turbulent fluctuations, a behaviour which depended on temperature. Burst swimming performance and sustained swimming increased by up to 53% as temperature increased from 15 to 20°C and 71% between 15 and 25°C. Furthermore, fish test area occupancy was dependent on thermal conditions, as well as on time-averaged velocities and turbulent fluctuations. This study suggests that invasive species can benefit from the raised temperatures predicted under climate change forecasts by improving swimming performance in flowing water potentially facilitating their further dispersal and subsequent establishment in lotic environments., (© 2021 The Authors.)

Eclampsia, clinically defined as unexplained seizure in a woman with preeclampsia, is a life threatening complication unique to the pregnant state. However, a subpopulation of women with seemingly uncomplicated pregnancies experience de novo seizure without preeclamptic signs or symptoms, suggesting pregnancy alone may predispose the brain to seizure. Here, we hypothesized that normal pregnancy lowers seizure threshold and investigated mechanisms by which pregnancy may affect seizure susceptibility, including neuroinflammation and plasticity of gamma-aminobutyric acid type A receptor (GABAAR) subunit expression. Seizure threshold was determined by quantifying the amount of pentylenetetrazole (PTZ) required to elicit electrical seizure in Sprague Dawley rats that were either nonpregnant (Nonpreg, n = 7) or pregnant (Preg; d20, n = 6). Seizure-induced vasogenic edema was also measured. Further, activation of microglia, a measure of neuroinflammation (n = 6-8/group), and GABAAR δ- and γ2-subunit protein expression in the cerebral cortex and hippocampus (n = 6/group) was determined. Seizure threshold was lower in Preg compared to Nonpreg rats (36.7±9.6 vs. 65.0±14.5 mg/kg PTZ; p<0.01) that was associated with greater vasogenic edema formation (78.55±0.11 vs. 78.04±0.19% water; p<0.05). The % of active microglia was similar between groups; however, pregnancy was associated with downregulation of cortical GABAAR-δ and hippocampal GABAAR-γ2 expression. Overall, pregnancy appears to be a state of increased seizure susceptibility that is not due to neuroinflammation, but rather is associated with reduced expression of GABAAR subunits and greater edema. Understanding neurophysiological changes occurring in normal pregnancy could allow for better prevention and management of de novo seizure, including pathologic states such as eclampsia.

Eclampsia, defined as unexplained seizure in a woman with preeclampsia, is a life-threatening complication of pregnancy with unclear etiology. Magnesium sulfate (MgSO4) is the leading eclamptic seizure prophylactic, yet its mechanism of action remains unclear. Here, we hypothesized severe preeclampsia is a state of increased seizure susceptibility due to blood-brain barrier (BBB) disruption and neuroinflammation that lowers seizure threshold. Further, MgSO4 decreases seizure susceptibility by protecting the BBB and preventing neuroinflammation. To model severe preeclampsia, placental ischemia (reduced uteroplacental perfusion pressure; RUPP) was combined with a high cholesterol diet (HC) to cause maternal endothelial dysfunction. RUPP+HC rats developed symptoms associated with severe preeclampsia, including hypertension, oxidative stress, endothelial dysfunction and fetal and placental growth restriction. Seizure threshold was determined by quantifying the amount of pentylenetetrazole (PTZ; mg/kg) required to elicit seizure in RUPP + HC ± MgSO4 and compared to normal pregnant controls (n = 6/group; gestational day 20). RUPP+HC rats were more sensitive to PTZ with seizure threshold being ∼ 65% lower vs. control (12.4 ± 1.7 vs. 36.7 ± 3.9 mg/kg PTZ; p<0.05) that was reversed by MgSO4 (45.7 ± 8.7 mg/kg PTZ; p<0.05 vs. RUPP+HC). BBB permeability to sodium fluorescein, measured in-vivo (n = 5-7/group), was increased in RUPP+HC vs. control rats, with more tracer passing into the brain (15.9 ± 1.0 vs. 12.2 ± 0.3 counts/gram ×1000; p<0.05) and was unaffected by MgSO4 (15.6 ± 1.0 counts/gram ×1000; p<0.05 vs. controls). In addition, RUPP+HC rats were in a state of neuroinflammation, indicated by 35 ± 2% of microglia being active compared to 9 ± 2% in normal pregnancy (p<0.01; n = 3-8/group). MgSO4 treatment reversed neuroinflammation, reducing microglial activation to 6 ± 2% (p<0.01 vs. RUPP+HC). Overall, RUPP+HC rats were in a state of augmented seizure susceptibility potentially due to increased BBB permeability and neuroinflammation. MgSO4 treatment reversed this, increasing seizure threshold and decreasing neuroinflammation, without affecting BBB permeability. Thus, reducing neuroinflammation may be one mechanism by which MgSO4 prevents eclampsia during severe preeclampsia.

Hemorrhage during parturition can lower blood pressure beyond the lower limit of cerebral blood flow (CBF) autoregulation that can cause ischemic brain injury. However, the impact of pregnancy on the lower limit of CBF autoregulation is unknown. We measured myogenic vasodilation, a major contributor of CBF autoregulation, in isolated posterior cerebral arteries (PCAs) from nonpregnant and late-pregnant rats (n = 10/group) while the effect of pregnancy on the lower limit of CBF autoregulation was studied in the posterior cerebral cortex during controlled hemorrhage (n = 8). Pregnancy enhanced myogenic vasodilation in PCA and shifted the lower limit of CBF autoregulation to lower pressures. Inhibition of nitric oxide synthase (NOS) prevented the enhanced myogenic vasodilation during pregnancy but did not affect the lower limit of CBF autoregulation. The shift in the autoregulatory curve to lower pressures during pregnancy is likely protective of ischemic injury during hemorrhage and appears to be independent of NOS.

Decreased peroxisome proliferator-activated receptor gamma (PPARγ) activity is thought to have a major role in preeclampsia through abnormal placental development. However, the role of PPARγ in adaptation of the uteroplacental vasculature that may lead to placental hypoperfusion and fetal growth restriction during pregnancy is not known. Here, pregnant Sprague-Dawley rats (n = 11/group) were treated during the second half of pregnancy with the PPARγ inhibitor GW9662 (10 mg/kg/day in food) or vehicle. Pregnancy outcome and PPARγ mRNA, vasodilation and structural remodeling were determined in maternal uterine and mesenteric arteries. PPARγ was expressed in uterine vascular tissue of both non-pregnant and pregnant rats with ~2-fold greater expression in radial vs. main uterine arteries. PPARγ mRNA levels were significantly higher in uterine compared to mesenteric arteries. GW9662 treatment during pregnancy did not affect maternal physiology (body weight, glucose, blood pressure), mesenteric artery vasodilation or structural remodeling of uterine and mesenteric vessels. Inhibition of PPARγ for the last 10 days of gestation caused decreased fetal weights on both day 20 and 21 of gestation that was associated with impaired vasodilation of radial uterine arteries in response to acetylcholine and sodium nitroprusside. These results define an essential role of PPARγ in the control of uteroplacental vasodilatory function during pregnancy, an important determinant of blood flow to the placenta and fetus. Strategies that target PPARγ activation in the uterine circulation could have important therapeutic potential in treatment of pregnancies complicated by hypertension, diabetes or preeclampsia.

Preeclampsia is a hypertensive disorder of pregnancy that affects many organs including the brain. Neurological complications occur during preeclampsia, the most serious of which is seizure known as eclampsia. Although preeclampsia can precede the eclamptic seizure, it often occurs during normal pregnancy, suggesting that processes associated with normal pregnancy can promote neuronal excitability. Here we investigated whether circulating inflammatory mediators that are elevated late in gestation when seizure also occurs are hyperexcitable to neuronal tissue. Evoked field potentials were measured in hippocampal slices in which control horse serum that slices are normally grown in, was replaced with serum from nonpregnant or late-pregnant Wistar rats for 48 h. We found that serum from pregnant, but not nonpregnant rats, caused hyperexcitability to hippocampal neurons and seizure activity that was abrogated by inhibition of tumor necrosis factor alpha (TNFα) signaling. Additionally, application of TNFα mimicked this increased excitability. Pregnant serum also caused morphological changes in microglia characteristic of activation, and increased TNFα mRNA expression that was not seen with exposure to nonpregnant serum. However, TNFα protein was not found to be elevated in pregnant serum itself, suggesting that other circulating factors during pregnancy caused activation of hippocampal slice cells to produce a TNFα-mediated increase in neuronal excitability. Lastly, although pregnant serum caused neuroinflammation and hyperexcitability of hippocampal slices, it did not increase blood-brain barrier permeability, nor were pregnant rats from which the serum was taken undergoing seizure. Thus, the BBB has an important role in protecting the brain from circulating neuroinflammatory mediators that are hyperexcitable to the brain during pregnancy. These studies provide novel insight into the underlying cause of eclampsia without elevated blood pressure and the protective role of the BBB that prevents exposure of the brain to hyperexcitable factors., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Circulating factors in preeclamptic women are thought to cause endothelial dysfunction and thereby contribute to the progression of this hypertensive condition. Despite the involvement of neurological complications in preeclampsia, there is a paucity of data regarding the effect of circulating factors on cerebrovascular function. Using a rat model of pregnancy, we investigated blood-brain barrier permeability, myogenic activity, and the influence of endothelial vasodilator mechanisms in cerebral vessels exposed intraluminally to plasma from normal pregnant or preeclamptic women. In addition, the role of vascular endothelial growth factor signaling in mediating changes in permeability in response to plasma was investigated. A 3-hour exposure to 20% normal pregnant or preeclamptic plasma increased blood-brain barrier permeability by ≈6.5- and 18.0-fold, respectively, compared with no plasma exposure (P<0.01). Inhibition of vascular endothelial growth factor receptor kinase activity prevented the increase in permeability in response to preeclamptic plasma but had no effect on changes in permeability of vessels exposed to normal pregnant plasma. Circulating factors in preeclamptic plasma did not affect myogenic activity or the influence of endothelium on vascular tone. These findings demonstrate that acute exposure to preeclamptic plasma has little effect on reactivity of cerebral arteries but significantly increases blood-brain barrier permeability. Prevention of increased permeability by inhibition of vascular endothelial growth factor signaling suggests that activation of this pathway may be responsible for increased blood-brain barrier permeability after exposure to preeclamptic plasma.

Peroxisome proliferator-activated receptor-γ (PPARγ), a ligand-activated transcription factor, has protective roles in the cerebral circulation and is highly activated during pregnancy. Thus, we hypothesized that PPARγ is involved in the adaptation of cerebral vasculature to pregnancy. Non-pregnant (NP) and late-pregnant (LP) rats were treated with a specific PPARγ inhibitor GW9662 (10 ]mg/kg/day, in food) or vehicle for 10 days and vascular function and structural remodeling were determined in isolated and pressurized posterior cerebral arteries (PCA). Expression of PPARγ and angiotensin type 1 receptor (AT1R) in cerebral (pial) vessels was determined by real-time RT-PCR. PPARγ inhibition decreased blood pressure and increased blood glucose in NP rats, but not in LP rats. PPARγ inhibition reduced dilation to acetylcholine and sodium nitroprusside in PCA from NP (p < 0.05 vs. LP-GW), but not LP rats. PPARγ inhibition tended to increase basal tone and myogenic activity in PCA from NP rats, but not LP rats. Structurally, PPARγ inhibition increased wall thickness in PCA from both NP and LP rats (p < 0.05), but increased distensibility only in PCA from NP rats. Pregnancy decreased expression of PPARγ and AT1R (p < 0.05) in cerebral arteries that was not affected by GW9662 treatment. These results suggest that PPARγ inhibition had significant effects on the function and structure of PCA in the NP state, but appeared to have less influence during pregnancy. Down-regulation of PPARγ and AT1R in cerebral arteries may be responsible for the lack of effect of PPARγ in cerebral vasculature and may be part of the vascular adaptation to pregnancy.

Peroxisome proliferator-activated receptor-gamma (PPAR-gamma) agonists have been shown to protect the cerebral vasculature, including the blood-brain barrier. In the present study, we investigated the effect of the PPAR-gamma agonist rosiglitazone on changes in venous permeability during chronic hypertension induced by nitric oxide synthase inhibition. Female Sprague-Dawley rats were either treated with N(G)-nitro-L-arginine methyl ester (L-NAME; 0.5 g/l in drinking water) for 5 wk (HTN; n = 8), L-NAME for 5 wk plus the PPAR-gamma agonist rosiglitazone (20 mg/kg in food) for the last 3 wk (HTN + Rosi; n = 5), L-NAME for 5 wk plus the superoxide dismutase mimetic Tempol (1 mmol/l in drinking water) for the last 3 wk (HTN + Tempol; n = 8), or were untreated controls (n = 9). Fluid filtration (J(v)/S) and hydraulic conductivity (L(p)) of cerebral veins were compared in vitro between groups after a step increase in pressure from 10 to 25 mmHg to mimic the change in hydrostatic pressure during acute hypertension. Hypertension increased J(v)/S by 2.2-fold and L(p) by 3.2-fold. Rosiglitazone treatment after 2 wk of hypertension completely reversed the increased J(v)/S and L(p) that occurred during hypertension, whereas Tempol had no effect. These results demonstrate that rosiglitazone was effective at reversing changes in venous permeability that occurred during chronic hypertension, an effect that does not appear to be related to its antioxidant properties. Our findings suggest that PPAR-gamma may be a key regulator of blood-brain barrier permeability and a potential therapeutic target during hypertension.

As part of a larger microbial source tracking (MST) study, several laboratories used library-based, phenotypic subtyping techniques to analyse fecal samples from known sources (human, sewage, cattle, dogs and gulls) and blinded water samples that were contaminated with the fecal sources. The methods used included antibiotic resistance analysis (ARA) of fecal streptococci, enterococci, fecal coliforms and E. coli; multiple antibiotic resistance (MAR) and Kirby-Bauer antibiotic susceptibility testing of E. coli; and carbon source utilization for fecal streptococci and E. coli. Libraries comprising phenotypic patterns of indicator bacteria isolated from known fecal sources were used to predict the sources of isolates from water samples that had been seeded with fecal material from the same sources as those used to create the libraries. The accuracy of fecal source identification in the water samples was assessed both with and without a cut-off termed the minimum detectable percentage (MDP). The libraries (approximately 300 isolates) were not large enough to avoid the artefact of source-independent grouping, but some important conclusions could still be drawn. Use of a MDP decreased the percentage of false-positive source identifications, and had little effect on the high percentage of true-positives in the most accurate libraries. In general, the methods were more prone to false-positive than to false-negative errors. The most accurate method, with a true-positive rate of 100% and a false-positive rate of 39% when analysed with a MDP, was ARA of fecal streptococci. The internal accuracy of the libraries did not correlate with the accuracy of source prediction in water samples, showing that one should not rely solely on parameters such as the average rate of correct classification of a library to indicate its predictive capabilities.

Penicillium citrinum cultures have been germinated on an H2O-based medium, resuspended on a D2O-based medium and treated with [l,2-(13)C2] acetate. The resulting citrinin (1) has been analysed by(2)H and(13)C nuclear magnetic resonance spectroscopy and information about the metabolism of hydrogen in citrinin biosynthesis has been deduced.