Studying the cellular basis of small bowel enteropathy using high-parameter flow cytometry in mouse models of primary antibody deficiency.

Background: Primary immunodeficiencies are heritable defects in immune system function. Antibody deficiency is the most common form of primary immunodeficiency in humans, can be caused by abnormalities in both the development and activation of B cells, and may result from B-cell-intrinsic defects or defective responses by other cells relevant to humoral immunity. Inflammatory gastrointestinal complications are commonly observed in antibody-deficient patients, but the underlying immune mechanisms driving this are largely undefined. Methods: In this study, several mouse strains reflecting a spectrum of primary antibody deficiency (IgA-/-, Aicda-/-, CD19-/- and JH -/-) were used to generate a functional small-bowel-specific cellular atlas using a novel high-parameter flow cytometry approach that allows for the enumeration of 59 unique cell subsets. Using this cellular atlas, we generated a direct and quantifiable estimate of immune dysregulation. This estimate was then used to identify specific immune factors most predictive of the severity of inflammatory disease of the small bowel (small bowel enteropathy). Results: Results from our experiments indicate that the severity of primary antibody deficiency positively correlates with the degree of immune dysregulation that can be expected to develop in an individual. In the SI of mice, immune dysregulation is primarily explained by defective homeostatic responses in T cell and invariant natural killer-like T (iNKT) cell subsets. These defects are strongly correlated with abnormalities in the balance between protein (MHCII-mediated) versus lipid (CD1d-mediated) antigen presentation by intestinal epithelial cells (IECs) and intestinal stem cells (ISCs), respectively. Conclusions: Multivariate statistical approaches can be used to obtain quantifiable estimates of immune dysregulation based on high-parameter flow cytometry readouts of immune function. Using one such estimate, we reveal a previously unrecognized tradeoff between iNKT cell activation and type 1 immunity that underlies disease in the small bowel. The balance between protein/lipid antigen presentation by ISCs may play a crucial role in regulating this balance and thereby suppressing inflammatory disease in the small bowel.

Studying the cellular basis of small bowel enteropathy using high-parameter flow cytometry in mouse models of primary antibody deficiency.

Background: Primary immunodeficiencies are heritable defects in immune system function. Antibody deficiency is the most common form of primary immunodeficiency in humans, can be caused by abnormalities in both the development and activation of B cells, and may result from B-cell-intrinsic defects or defective responses by other cells relevant to humoral immunity. Inflammatory gastrointestinal complications are commonly observed in antibody-deficient patients, but the underlying immune mechanisms driving this are largely undefined. Methods: In this study, several mouse strains reflecting a spectrum of primary antibody deficiency (IgA -/- , Aicda -/- , CD19 -/- and J H -/- ) were used to generate a functional small-bowel-specific cellular atlas using a novel high-parameter flow cytometry approach that allows for the enumeration of 59 unique cell subsets. Using this cellular atlas, we generated a direct and quantifiable estimate of immune dysregulation. This estimate was then used to identify specific immune factors most predictive of the severity of inflammatory disease of the small bowel (small bowel enteropathy). Results: Results from our experiments indicate that the severity of primary antibody deficiency positively correlates with the degree of immune dysregulation that can be expected to develop in an individual. In the SI of mice, immune dysregulation is primarily explained by defective homeostatic responses in T cell and invariant natural killer-like T (iNKT) cell subsets. These defects are strongly correlated with abnormalities in the balance between protein (MHCII-mediated) versus lipid (CD1d-mediated) antigen presentation by intestinal epithelial cells (IECs) and intestinal stem cells (ISCs), respectively. Conclusions: Multivariate statistical approaches can be used to obtain quantifiable estimates of immune dysregulation based on high-parameter flow cytometry readouts of immune function. Using one such estimate, we reveal a previously unrecognized tradeoff between iNKT cell activation and type 1 immunity that underlies disease in the small bowel. The balance between protein/lipid antigen presentation by ISCs may play a crucial role in regulating this balance and thereby suppressing inflammatory disease in the small bowel.

REMAP Periop: a randomised, embedded, multifactorial adaptive platform trial protocol for perioperative medicine to determine the optimal enhanced recovery pathway components in complex abdominal surgery patients within a US healthcare system.

INTRODUCTION: Implementation of enhanced recovery pathways (ERPs) has resulted in improved patient-centred outcomes and decreased costs. However, there is a lack of high-level evidence for many ERP elements. We have designed a randomised, embedded, multifactorial, adaptive platform perioperative medicine (REMAP Periop) trial to evaluate the effectiveness of several perioperative therapies for patients undergoing complex abdominal surgery as part of an ERP. This trial will begin with two domains: postoperative nausea/vomiting (PONV) prophylaxis and regional/neuraxial analgesia. Patients enrolled in the trial will be randomised to arms within both domains, with the possibility of adding additional domains in the future. METHODS AND ANALYSIS: In the PONV domain, patients are randomised to optimal versus supraoptimal prophylactic regimens. In the regional/neuraxial domain, patients are randomised to one of five different single-injection techniques/combination of techniques. The primary study endpoint is hospital-free days at 30 days, with additional domain-specific secondary endpoints of PONV incidence and postoperative opioid consumption. The efficacy of an intervention arm within a given domain will be evaluated at regular interim analyses using Bayesian statistical analysis. At the beginning of the trial, participants will have an equal probability of being allocated to any given intervention within a domain (ie, simple 1:1 randomisation), with response adaptive randomisation guiding changes to allocation ratios after interim analyses when applicable based on prespecified statistical triggers. Triggers met at interim analysis may also result in intervention dropping. ETHICS AND DISSEMINATION: The core protocol and domain-specific appendices were approved by the University of Pittsburgh Institutional Review Board. A waiver of informed consent was obtained for this trial. Trial results will be announced to the public and healthcare providers once prespecified statistical triggers of interest are reached as described in the core protocol, and the most favourable interventions will then be implemented as a standardised institutional protocol. TRIAL REGISTRATION NUMBER: NCT04606264.

The Year in Cardiothoracic Transplant Anesthesia: Selected Highlights From 2021 Part II: Cardiac Transplantation.

This article spotlights the research highlights of this year that specifically pertain to the specialty of anesthesia for heart transplantation. This includes the research on recent developments in the selection and optimization of donors and recipients, including the use of donation after cardiorespiratory death and extended criteria donors, the use of mechanical circulatory support and nonmechanical circulatory support as bridges to transplantation, the effect of COVID-19 on heart transplantation candidates and recipients, and new advances in the perioperative management of these patients, including the use of echocardiography and postoperative outcomes, focusing on renal and cerebral outcomes.

B-cell-specific MhcII regulates microbiota composition in a primarily IgA-independent manner.

Background: The expression of major histocompatibility complex class II (MhcII) molecules on B cells is required for the development of germinal centers (GCs) in lymphoid follicles; the primary sites for the generation of T-cell-dependent (TD) antibody responses. Peyer's patches (PPs) are secondary lymphoid tissues (SLOs) in the small intestine (SI) that give rise to high-affinity, TD antibodies (mainly immunoglobulin A (IgA)) generated against the microbiota. While several studies have demonstrated that MhcII antigen presentation by other immune cells coordinate TD IgA responses and regulate microbiota composition, whether or not B-cell-specific MhcII influences gut microbial ecology is unknown. Methods: Here, we developed a novel Rag1 -/- adoptive co-transfer model to answer this question. In this model, Rag1 -/- mice were reconstituted with naïve CD4+ T cells and either MhcII-sufficient or MhcII-deficient naïve B cells. Subsequent to this, resulting shifts in microbiota composition was characterized via 16S rRNA gene sequencing of SI-resident and fecal bacterial communities. Results: Results from our experiments indicate that SLO development and reconstitution of an anti-commensal TD IgA response can be induced in Rag1 -/- mice receiving T cells and MhcII-sufficient B cells, but not in mice receiving T cells and MhcII-deficient B cells. Results from our 16S experiments confirmed that adaptive immunity is a relevant host factor shaping microbial ecology in the gut, and that its impact was most pronounced on SI-resident bacterial communities. Conclusion: Our data also clearly establishes that MhcII-mediated cognate interactions between B cells and T cells regulates this effect by maintaining species richness in the gut, which is a phenotype commonly associated with good health. Finally, contrary to expectations, our experimental results indicate that IgA was not responsible for driving any of the effects on the microbiota ascribed to the loss of B cell-specific MhcII. Collectively, results from our experiments support that MhcII-mediated antigen presentation by B cells regulates microbiota composition and promotes species richness through an IgA-independent mechanism.

Basic Transesophageal Echocardiography Education for Senior Anesthesiology Residents-Institutional Experience.

OBJECTIVE: The use of basic transesophageal echocardiography (TEE) in critically ill and older surgical patients can change patient management and improve outcomes after noncardiac surgery. The authors hypothesized that educating the future generation on basic TEE skills by an intense two-month rotation will help them achieve basic TEE certification by the National Board of Echocardiography (NBE) and facilitate good use of their skills for patient care during their practice. DESIGN: This is a descriptive report of graduating anesthesiology residents who completed two months basic TEE rotation at the authors' residency program between 2013 and 2019. The authors report the clinical training goals, NBE testamur and certification status, and a survey report on the use of basic TEE skills in their practice SETTINGS: University medical center. PARTICIPANTS: Residents who completed two months basic TEE rotation during their Clinical Anesthesia (CA)-3 year. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Of a total of 115 residents, 67 (58%) elected basic TEE rotation. The NBE basic TEE certification and testamur status were achieved by 12 (21%) and 14 (24%) eligible residents, respectively. Residents (n = 43) personally performed 73 ± 21 (mean ± standard deviation) and reviewed 72 ± 28 (mean ± standard deviation basic TEE studies before graduation. The survey indicated that 63.4% of residents trained in basic TEE did not use their skills in their practice. CONCLUSIONS: Two months' basic TEE rotation was able to fulfill its educational goals (testamur status and clinical training) but fell short on achieving NBE certification rate and its ultimate impact on practice and patient care.

Perianesthesia Care of the Oncologic Patient Undergoing Cytoreductive Surgery with Hyperthermic Intraperitoneal Chemotherapy: A Retrospective Study.

PURPOSE: This study was to understand the perianesthesia care for patients undergoing cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS  + HIPEC). METHOD: This is a retrospective study. DESIGN: The perioperative electronic medical records of 189 CRS  + HIPEC surgical cases at a hospital of Western Pennsylvania from 2012 to 2018 were analyzed to study the characteristics of perianesthesia care for CRS  + HIPEC surgery. FINDINGS: The patients' median age was 57 (range 21-83) years, and 60% were men. The mean anesthesia time was 10.47 ± 2.54 hours. Most tumors were appendix or colorectal in origin, and the mean peritoneal cancer index score was 16.19 ± 8.76. The mean estimated blood loss was 623 ± 582 mL. The mean total intravenous crystalloid administered was 8,377 ± 4,100 mL. Fifty-two patients received packed red blood cells during surgery. Postoperatively, 100% of the patients were transferred to the intensive care unit. A majority (52%) of patients were extubated in the operating room. Median lengths of hospital and intensive care unit stays were 13 and 2 days, respectively. A majority (73%) of patients had 1 or more postoperative complications and 29% of patients experienced major postoperative complications (Clavien-Dindo grade III or higher) during the hospital stay. Prolonged hospitalization was owing to gastrointestinal dysfunctions and respiratory failure related to atelectasis and pleural effusion. CONCLUSIONS: CRS  + HIPEC is a major surgery with numerous challenges to the perianesthesia care team regarding hemodynamic adjustment, pain control, and postoperative complications, which demand training and future studies from the perianesthesia care team.

Emotional intelligence and the relationship to resident performance: a multi-institutional study.

STUDY OBJECTIVE: To test the hypothesis that emotional intelligence, as measured by a BarOn Emotional Quotient Inventory (EQ-i), the 125-item version personal inventory (EQ-i:125), correlates with resident performance. DESIGN: Survey (personal inventory) instrument. SETTING: Five U.S. academic anesthesiology residency programs. PARTICIPANTS: Postgraduate year (PGY) 2, 3, and 4 residents enrolled in university-based anesthesiology residency programs. MEASUREMENTS: Residents confidentially completed the BarOn EQ-i:125 personal inventory. The deidentified resident evaluations were sent to the principal investigator of a separate data collection study for data analysis. Data collected from the inventory were correlated with daily evaluations of the residents by residency program faculty. Results of the individual BarOn EQ-i:125 and daily faculty evaluations of the residents were compiled and analyzed. MAIN RESULTS: Univariate correlation analysis and multivariate canonical analysis showed that some aspects of the BarOn EQ-i:125 were significantly correlated with, and likely to be predictors of, resident performance. CONCLUSIONS: Emotional intelligence, as measured by the BarOn EQ-i personal inventory, has considerable promise as an independent indicator of performance as an anesthesiology resident.

Peripheral intravenous catheter infiltration: anesthesia providers do not adhere to their own ideas of best practice.

STUDY OBJECTIVE: To survey anesthesia providers for their opinion on "best practice" in perioperative peripheral intravenous catheter (PIV) management, and to determine if they follow those opinions. DESIGN: Survey instrument. SETTING: Academic medical center. SUBJECTS: 266 United States (U.S.) anesthesia provider respondents (attending anesthesiologists, anesthesiology residents, anesthesia assistants, certified registered nurse-anesthetists and student registered nurse-anesthetists). MEASUREMENTS: Between May 2009 and October 2010 a national survey was distributed to individuals who provide intraoperative anesthesia care to patients. Results were gathered via the SurveyMonkey database. MAIN RESULTS: 266 anesthesia providers from across the U.S. took part in the survey. The majority (70%) had less than 5 years' experience. Nearly 90% of respondents cared for a patient with an intravenous catheter infiltration at some point during their training; 7% of these patients required medical intervention. Intravenous assessment and documentation practices showed great variability. Management and documentation of PIVs was more aggressive and vigilant when respondents were asked about "best practice" than about actual management. CONCLUSION: There is no commonly accepted standard for management and documentation of PIVs in the operating room. From our survey, what providers think is "best practice" in the management and documentation of PIVs is not what is being done.

Modulatory effects of melatonin on behavior, hemolymph metabolites, and neurotransmitter release in crayfish.

Melatonin affects a variety of circadian processes such as behavior and neurotransmitter release in vertebrates. Crayfish melatonin production occurs in the eyestalks, and the cycle of production may change seasonally. To date, however, melatonin's roles and mechanisms of action in crustacean physiology are unclear. We injected melatonin or saline into crayfish in scotophase and monitored activity and hemolymph glucose/lactate over 24 h in early spring. Crayfish were significantly more active in photophase versus the expected scotophase, and had concurrent glucose/lactate peaks. Melatonin reversed the activity pattern, causing a scotophase activity peak, but not the glucose/lactate patterns. This study was repeated in late summer, during which control activity and glucose/lactate levels were elevated in scotophase. Melatonin decreased the amplitude of scotophase activity and glucose/lactate, eliminating activity and glucose cycles. We also injected melatonin or saline at various times of day in early summer and monitored locomotor activity for 1 h. Controls had high activity at 1200 (mid-photophase) and 2100 h (early scotophase), and melatonin increased activity at 1200 h but decreased it at 2100 h. Melatonin also increased activity at 1500 h but not 1800 h (late photophase). Next, we examined the influence of melatonin on crayfish neurophysiology. Melatonin (10 microM) enhanced synaptic transmission at the neuromuscular junction (NMJ). The presynaptic action resulted in more vesicles being released during evoked stimulation. Our study indicates that melatonin may have a phylogenetically conserved role in the transduction of circadian information in invertebrates as in vertebrates. Behavioral and physiological effects may be mediated by modulation of central pathways, enhanced at the peripheral level via neuromodulation of the NMJ.

Long-term in vitro maintenance of neuromuscular junction activity of Drosophila larvae.

The larval Drosophila neuromuscular junction (NMJ) has proven to be an excellent system to test fundamental aspects of synaptic transmission, such as relationships among ion channel function, subtypes of glutamate receptors, and the functions of synaptic proteins in the presynaptic compartment. Recent advances in understanding bi-directional communication between nerves and muscles of Drosophila are helping uncover developmental as well as maintenance cues that could be applicable to all chemical synapses. The development of HL3 medium makes it possible to record synaptic responses at NMJs for prolonged periods of time. We demonstrate that media commonly used to culture CNS neurons and imaginal disks of Drosophila such as Schneider's and M3 completely block glutamatergic synaptic transmission at the NMJ. The depressed postsynaptic excitatory junction potentials (EJPs) partially recover from exposure to such media shortly after switching to the HL3 medium. Preliminary results from NMJs of filleted 3rd instar larvae for 4 days in vitro bathed in a modified HL3 medium show great promise. The resting membrane potential and the EJP amplitudes after 4 days in vitro are normal. These results demonstrate the possibility for chronic studies of developmental regulation in culture, which in some cases are impractical in the whole animal.