Search

The ability to distinguish endometrial serous carcinoma (SC) from high-grade endometrioid adenocarcinoma is of great importance given their differences in prognosis and management. In practice, this distinction typically relies upon the use of a focused immunohistochemical panel including p53, p16, and mismatch repair proteins. The expression of p16 is characteristically strong and diffuse in SCs, and weak and/or patchy in many high-grade endometrioid adenocarcinomas. Here, we report a subset of SCs that are entirely negative for p16 immunostaining, a pattern we refer to as "p16 null." This pattern was identified in 2 of 63 cases of SC diagnosed at our institution-1 with histologically classic features and 1 with ambiguous high-grade histologic features. These tumors otherwise showed a SC signature by immunohistochemical and demonstrated an SC pattern of genetic mutations. No mutation in the gene for p16, cyclin-dependent kinase inhibitor 2A (CDKN2A), was identified in either case. However, molecular correlates for the absent p16 expression were present, including homozygous deletion of CDKN2A in one case and hemizygous deletion of CDKN2A with promotor hypermethylation of the remaining allele in the other case. To our knowledge, this constitutes the first report conclusively demonstrating the existence of a small subset of SCs that are completely negative by p16 immunohistochemistry, and the molecular lesions responsible for this pattern. In the context of an otherwise clinically and histologically classic example of SC, we endorse this "null" p16 staining pattern as an alternative aberrant staining pattern that should not deter one from committing to this diagnosis.

Rhythmic breathing is generated by neural circuits located in the brainstem. At its core is the preBötzinger Complex (preBötC), a region of the medulla, necessary for the generation of rhythmic breathing in mammals. The preBötC is comprised of various neuronal populations expressing neurokinin-1 receptors, the cognate G-protein-coupled receptor of the neuropeptide substance P (encoded by the tachykinin precursor 1 orTac1). Neurokinin-1 receptors are highly expressed in the preBötC and destruction or deletion of neurokinin-1 receptor-expressing preBötC neurons severely impairs rhythmic breathing. Application of substance P to the preBötC stimulates breathing in rodents, however substance P is often associated with nociception and locomotion in various brain regions, suggesting thatTac1neurons found in the preBötC may have diverse functional roles. Here, we aim to characterize the role ofTac1-expressing preBötC neurons in the generation of rhythmic breathingin vivo, as well as motor behaviors. Using a cre-lox recombination approach, we injected adeno-associated virus containing the excitatory channelrhodopsin-2 ChETA in the preBötC region ofTac1-cre mice. Using a combination of histological, optogenetics, respiratory, and behavioral assays, we defined the identity and the role ofTac1preBötC neurons. These neurons are glutamatergic and their stimulation promotes rhythmic breathing in both anesthetized and freely moving/awake animals, but also triggers locomotion and overcomes respiratory depression by opioid drugs. Overall, our study identifies a new population of excitatory preBötC with major role in rhythmic breathing and behaviors.

One of the major goals for translational sleep science and medicine is to identify viable and tractable pharmacological targets for obstructive sleep apnea and other respiratory disorders of sleep or sedation. In the present preclinical study in rats, we performed a randomized, within-subject, repeated-measures design over six intervention study days in chronically instrumented male and female rats with systemic peripheral administration of vehicle controls, the thyrotropin-releasing hormone analog taltirelin at two doses, all with and without coadministered trazodone. Trazodone was included due to clinical interest in the context of sleep apnea pharmacotherapy as it can suppress arousal without compromising pharyngeal muscle activity. These preclinical findings newly identify taltirelin as a stable upper airway-preferring respiratory stimulant with arousal properties. These traits have potential favorable relevance to some respiratory disorders but not others, as identified and discussed.

In this study the effects of high temperature and moisture on the impact damage resistance and mechanical strength of Nextel 610/alumina silicate ceramic matrix composites were experimentally evaluated. Composite laminates were exposed to either a 1050°C isothermal furnace-based environment for 30 consecutive days at 6 h a day, or 95% relative humidity environment for 13 consecutive days at 67°C. Low velocity impact, tensile and short beam strength tests were performed on both ambient and environmentally conditioned laminates and damage was characterized using a combination of non-destructive and destructive techniques. High temperature and humidity environmental exposure adversely affected the impact resistance of the composite laminates. For all the environments, planar internal damage area was greater than the back side dent area, which in turn was greater than the impactor side dent area. Evidence of environmental embrittlement through a stiffer tensile response was noted for the high temperature exposed laminates while the short beam strength tests showed greater propensity for interlaminar shear failure in the moisture exposed laminates. Destructive evaluations exposed larger, more pronounced delaminations in the environmentally conditioned laminates in comparison to the ambient ones. External damage metrics of the impactor side dent depth and area directly influenced the post-impact tensile strength of the laminates while no such trend between internal damage area and residual strength could be ascertained.

BACKGROUND: Polycystic kidney disease (PKD) accounts for approximately 15% of kidney transplants, but long-term outcomes in patients with PKD who have received a kidney transplant are not well understood. METHODS: In primary recipients of kidney transplants at our center (1994–2014), we compared outcomes of underlying PKD (N=619) with other native diseases (non-PKD, N=4312). Potential factors influencing outcomes in PKD were evaluated using Cox proportional-hazards regression and a rigorous multivariable model. RESULTS: Patients with PKD were older and were less likely to be sensitized or to experience delayed graft function (DGF). Over a median follow-up of 5.6 years, 1256 of all recipients experienced death-censored graft failure (DCGF; 115 patients with PKD) and 1617 died (154 patients with PKD). After adjustment for demographic, dialysis, comorbid disease, surgical, and immunologic variables, patients with PKD had a lower risk of DCGF (adjusted hazard ratio [aHR], 0.73; 95% CI, 0.57 to 0.93; P=0.01) and death (aHR, 0.62; 95% CI, 0.51 to 0.75; P

This case study is useful for leadership for change or leadership theory in education and other disciplines. It describes the process of including multiple stakeholders in a major revision of a large educator preparation program after state legislation mandates. Student discussions can focus on change goals and patterns of planned change, leading mandated change efforts, and resistance to change. Students can focus on a leader’s role in several ways: as the higher-education leader (Dean), as the field partner leader (K–12 schools), and as the faculty committee leader. The case can be used to examine laws affecting school policy, and/or school leadership and its influence on organizational culture. Students discuss the perspective of multiple roles and how the Dean can resolve the situation successfully.

Children of Migrant and Seasonal Farmworkers (MSFWs) in the United States face educational challenges from language barriers and disjointed schooling due to migration and other factors. This quasi-...

This chapter describes a collaborative action research project in which one post-secondary instructor used the experiences in her undergraduate teacher education course to learn how to best support students and peers in a health crisis and social justice uncertainty climate. The authors used empathy and care theories and universal design for learning (UDL) to plan, implement, and reflect on ways to empathize and show care for students in a course that was online due to COVID-19. Using the action research processes, the authors found five themes related to using UDL practices and showing empathy and caring. They conclude with recommendations for other instructors interested in supporting their students in online classes and in times of crisis.

Alterations in thalamic GABAergic signaling are implicated in mediating the rise in 12-30 Hz electroencephalogram (EEG) activity that signals anesthetic-induced loss-of-consciousness with GABAA receptor-targeting general anesthetics. A number of modeling studies have identified that anesthetic-induced alterations in thalamocortico-corticothalamic signaling in the same network that generates sleep spindles would be sufficient to elicit this key EEG signature of anesthetic hypnosis with general anesthetic agents. Accordingly, we hypothesize that targeted stimulation of this thalamic GABAergic circuitry into a sleep-spindle mode of activity would promote the general anesthetic effects of etomidate. We recorded EEG activity and loss-of-righting reflex in transgenic mice expressing channel rhodopsin-2 on GABAergic neurons (ChR2-VGAT, n = 8) and control, wild-type mice (C57BL/6J, n = 8). On two consecutive days mice were randomly assigned to receive spindle-rhythm stimulation via an optical probe targeting the left reticular thalamic nucleus or no stimulation. After an initial 30-minute recording, mice were administered etomidate (12 mg/kg, intraperitoneal) and recorded for 90 min with or without optical stimulation. Etomidate elicited an increase in 12-30 Hz EEG power in wild-type and ChR2-VGAT mice for 20 min following administration (p

Obstructive sleep apnea (OSA) occurs exclusively during sleep due to reduced tongue motor activity. Withdrawal of excitatory inputs to the hypoglossal motor nucleus (HMN) from wake to sleep contributes to this reduced activity. Several awake–active neurotransmitters with inputs to the HMN (e.g. serotonin [5-HT]) inhibit K+ leak mediated by TASK-1/3 channels on hypoglossal motoneurons, leading to increased neuronal activity in vitro. We hypothesize that TASK channel inhibition at the HMN will increase tongue muscle activity in vivo and modulate responses to 5-HT. We first microperfused the HMN of anesthetized rats with TASK channel inhibitors: doxapram (75 μM, n = 9), A1899 (25 μM, n = 9), ML365 (25 μM, n = 9), acidified artificial cerebrospinal fluid (ACSF, pH = 6.25, n = 9); and a TASK channel activator terbinafine (50 μM, n = 9); all with and without co-applied 5-HT (10 mM). 5-HT alone at the HMN increased tongue motor activity (202.8% ± 45.9%, p < 0.001). However, neither the TASK channel inhibitors, nor activator, at the HMN changed baseline tongue activity (p > 0.716) or responses to 5-HT (p > 0.127). Tonic tongue motor responses to 5-HT at the HMN were also not different (p > 0.05) between ChAT-Cre:TASKf/f mice (n = 8) lacking TASK-1/3 channels on cholinergic neurons versus controls (n = 10). In freely behaving rats (n = 9), microperfusion of A1899 into the HMN increased within-breath phasic tongue motor activity in wakefulness only (p = 0.005) but not sleep, with no effects on tonic activity across all sleep–wake states. Together, the findings suggest robust maintenance of tongue motor activity despite various strategies for TASK channel manipulation targeting the HMN in vivo, and thus currently do not support this target and direction for potential OSA pharmacotherapy.

Thyrotropin-releasing hormone (TRH) is produced by the hypothalamus but most brain TRH is located elsewhere where it acts as a neuromodulator. TRH-positive neurons project to the hypoglossal motoneuron pool where TRH receptor RNA shows a high degree of differential expression compared with the rest of the brain. Strategies to modulate hypoglossal motor activity are of physiological and clinical interest given the potential for pharmacotherapy for obstructive sleep apnea (OSA), a common and serious respiratory disorder. Here, we identified the effects on tongue motor activity of TRH and a specific analog (taltirelin) applied locally to the hypoglossal motoneuron pool and systemically in vivo. Studies were performed under isoflurane anesthesia and across sleep–wake states in rats. In anesthetized rats, microperfusion of TRH (n = 8) or taltirelin (n = 9) into the hypoglossal motoneuron pool caused dose-dependent increases in tonic and phasic tongue motor activity (both p < 0.001). However, the motor responses to TRH were biphasic, being significantly larger “early” in the response versus at the end of the intervention (p ≤ 0.022). In contrast, responses to taltirelin were similar “early” versus “late” (p ≥ 0.107); i.e. once elicited, the motor responses to taltirelin were sustained and maintained. In freely behaving conscious rats (n = 10), microperfusion of 10 μM taltirelin into the hypoglossal motoneuron pool increased tonic and phasic tongue motor activity in non-rapid-eye-movement (REM) sleep (p ≤ 0.038). Intraperitoneal injection of taltirelin (1 mg/kg, n = 16 rats) also increased tonic tongue motor activity across sleep–wake states (p = 0.010). These findings inform the studies in humans to identify the potential beneficial effects of taltirelin for breathing during sleep and OSA.

Persistent and stable respiratory activity across behavioral states is key to homeostasis. Extrasynaptic δ-subunit containing GABAA receptors (δGABAARs) mediate tonic inhibition and regulate network activity. However, the influence of δGABAARs on respiratory rhythm and motor outputs is unknown. We manipulated extra-synaptic GABAA receptor function in the preBötzinger Complex (preBötC), a site central to the generation of inspiratory motor activity in mammals. Activation of preBötC δGABAARs in anesthetized rats and wild-type mice decreased breathing rate. In δGABAAR knockout (Gabrd−/−) mice, however, δGABAARs activation had no effect on breathing rate. We then found that during active wakefulness associated with behaviors and movements, diaphragm activation was higher in the Gabrd−/− compared to wild-type mice, but not in other states. These findings identify that δGABAARs modulate the respiratory network, which is critical to understand how δGABAARs change breathing in pathological conditions affecting extra-synaptic GABAA receptor function such as exposure to anesthetics and neurosteroids.

This article outlines the fundamental brain mechanisms that control sleep-wake patterns and reviews how pathologic changes in these control mechanisms contribute to common sleep disorders.Discrete but interconnected clusters of cells located within the brainstem and hypothalamus comprise the circuits that generate wakefulness, non-rapid eye movement (non-REM) sleep, and REM sleep. These clusters of cells use specific neurotransmitters, or collections of neurotransmitters, to inhibit or excite their respective sleep- and wake-promoting target sites. These excitatory and inhibitory connections modulate not only the presence of wakefulness or sleep, but also the levels of arousal within those states, including the depth of sleep, degree of vigilance, and motor activity. Dysfunction or degeneration of wake- and sleep-promoting circuits is associated with narcolepsy, REM sleep behavior disorder, and age-related sleep disturbances.Research has made significant headway in identifying the brain circuits that control wakefulness, non-REM, and REM sleep and has led to a deeper understanding of common sleep disorders and disturbances.

The energetics controlling delamination versus echelon crack advance in a tape composite laminate subjected to anti-plane shear loading are studied. The finite element method is used to model both single and multiple echelon cracks that intersect the planar delamination front. Energy release rates are determined along the echelon crack peripheries and along the planar delamination front. Various echelon crack shapes are evaluated in order to represent progressive stages of growth. It is shown that the echelon cracks advance due to primarily mode I conditions, whereas a mode III criterion is appropriate for predicting advance of the planar delamination. It is further shown that mode I advance of the echelon crack and mode III advance of the delamination are competing yet coupled processes, and that the sequence of events predicted by this approach agrees with what has been observed experimentally.

Motoneurons are the final output pathway for the brain’s influence on behavior. Here we identify properties of hypoglossal motor output to the tongue musculature. Tongue motor control is critical to the pathogenesis of obstructive sleep apnea, a common and serious sleep-related breathing disorder. Studies were performed on mice expressing a light sensitive cation channel exclusively on cholinergic neurons (ChAT-ChR2(H134R)-EYFP). Discrete photostimulations under isoflurane-induced anesthesia from an optical probe positioned above the medullary surface and hypoglossal motor nucleus elicited discrete increases in tongue motor output, with the magnitude of responses dependent on stimulation power (P in-vivo and identifies REM sleep specific suppression of net motor excitability and responsivity.

BACKGROUND: Chromosome instability (CIN) generates genetic and karyotypic diversity and is common in hematological malignancies. Low to moderate levels of CIN are well tolerated and can promote cancer proliferation; however, high levels of CIN are lethal. Thus, CIN may serve both as a prognostic factor to predict clinical outcome and as a predictive biomarker. METHODS: A retrospective study was performed to evaluate CIN in acute myeloid leukemia (AML). Chromosome mis-segregation frequency was correlated with clinical outcome in bone marrow core biopsy specimens from 17 AML cases. Additionally, we induced chromosome segregation errors in AML cell lines with AZ3146, an inhibitor of the Mps1 mitotic checkpoint kinase to quantify the phenotypic effects of high CIN. RESULTS: We observed a broad distribution of chromosome mis-segregation frequency in AML bone marrow core specimens. High CIN correlated with complex karyotype AML, as expected, although there was no clear survival effect. In addition to CIN, experimentally inducing chromosome segregation errors by Mps1 inhibition in AML cell lines causes DNA damage, micronuclei formation and upregulation of interferon stimulated genes (ISGs). CONCLUSIONS: High levels of CIN appear to be immunostimulatory, suggesting an opportunity to combine mitotic checkpoint inhibitors with immunotherapy in treatment of AML.

Opioid drugs are the mainstay of pain management but present the side-effect of respiratory depression that can be lethal with overdose. In addition to their respiratory effect, opioids also induce a profound sedative state and produce electrocortical features characteristic of a state of reduced brain arousal, similar to anaesthesia or sleep. In such states, respiratory activity depends more on the integrity of the brainstem respiratory network than it does during wakefulness. Accordingly, we propose that sedation by fentanyl induces specific electrocortical changes consistent with reduced brain arousal, and that the magnitude of respiratory depression is associated with distinct electrocortical changes. To these aims, we determined the effects of systemic injections of fentanyl (dosage 100 µg ·kg) versus control on electrocortical and respiratory activities of freely-behaving rats. We found that fentanyl induced electrocortical changes that differed from those observed in sleep or wakefulness. Fentanyl increased δ (1–3 Hz) frequency power (P 0.001), but reduced α (7.5–13.5 Hz) and β2 (20–30 Hz) powers (P = 0.012 and P 0.001, respectively), when compared to wakefulness. Interestingly, respiratory rate depression by fentanyl was significantly correlated with increased θ power (R = 0.61, P 0.001), therefore showing a clear association between electrocortical activity and the magnitude of respiratory rate depression. Overall, we provide new evidence linking specific electrocortical changes to the severity of respiratory depression by opioids, which highlights the importance of considering the cortical and subcortical effects of opioids in addition to their impacts on breathing when evaluating opioid-induced respiratory depression.

Appropriate levels of muscle tone are needed to support waking behaviors such as sitting or standing. However, it is unclear how the brain functions to couple muscle tone with waking behaviors. Cataplexy is a unique experiment of nature in which muscle paralysis involuntarily intrudes into otherwise normal periods of wakefulness. Cataplexy therefore provides the opportunity to identify the circuit mechanisms that couple muscle tone and waking behaviors. Here, we tested the long-standing hypothesis that muscle paralysis during cataplexy is caused by recruitment of the brainstem circuit that induces muscle paralysis during REM sleep. Using behavioral, electrophysiological, and chemogenetic strategies, we found that muscle tone and arousal state can be decoupled by manipulation of the REM sleep circuit (the sublaterodorsal tegmental nucleus [SLD]). First, we show that silencing SLD neurons prevents motor suppression during REM sleep. Second, we show that activating these same neurons promotes cataplexy in narcoleptic (orexin-/-) mice, whereas silencing these neurons prevents cataplexy. Most importantly, we show that SLD neurons can decouple motor activity and arousal state in healthy mice. We show that SLD activation triggers cataplexy-like attacks in wild-type mice that are behaviorally and electrophysiologically indistinguishable from cataplexy in orexin-/- mice. We conclude that the SLD functions to engage arousal-motor synchrony during both wakefulness and REM sleep, and we propose that pathological recruitment of SLD neurons could underlie cataplexy in narcolepsy.

The detection of acquired copy-number abnormalities (CNAs) and copy-neutral loss of heterozygosity (CN-LOH) in neoplastic disorders by chromosomal microarray analysis (CMA) has significantly increased over the past few years with respect to both the number of laboratories utilizing this technology and the broader number of tumor types being assayed. This highlights the importance of standardizing the interpretation and reporting of acquired variants among laboratories. To address this need, a clinical laboratory-focused workgroup was established to draft recommendations for the interpretation and reporting of acquired CNAs and CN-LOH in neoplastic disorders. This project is a collaboration between the American College of Medical Genetics and Genomics (ACMG) and the Cancer Genomics Consortium (CGC). The recommendations put forth by the workgroup are based on literature review, empirical data, and expert consensus of the workgroup members. A four-tier evidence-based categorization system for acquired CNAs and CN-LOH was developed, which is based on the level of available evidence regarding their diagnostic, prognostic, and therapeutic relevance: tier 1, variants with strong clinical significance; tier 2, variants with some clinical significance; tier 3, clonal variants with no documented neoplastic disease association; and tier 4, benign or likely benign variants. These recommendations also provide a list of standardized definitions of terms used in the reporting of CMA findings, as well as a framework for the clinical reporting of acquired CNAs and CN-LOH, and recommendations for how to deal with suspected clinically significant germline variants.

Background Alterations in thalamic γ-aminobutyric acid–mediated signaling are thought to underlie the increased frontal α-β frequency electrocortical activity that signals anesthetic-induced loss of consciousness with γ-aminobutyric acid receptor type A (GABAAR)–targeting general anesthetics. The general anesthetic etomidate elicits phasic extrasynaptic GABAAR activation (“spillover” inhibition) at thalamocortical neurons in vitro. We hypothesize that this action of etomidate at the thalamus is sufficient to trigger an increase in frontal α-β frequency electrocortical activity and that this effect of etomidate is fully recapitulated by enhanced thalamic spillover inhibition in vivo. Methods We recorded electrocortical activity and sleep–wake behavior in freely behaving wild-type (n = 33) and extrasynaptic δ-subunit–containing GABAAR knockout mice (n = 9) during bilateral microperfusion of the thalamus with etomidate and/or other pharmacologic agents that influence GABAAR or T-type Ca2+ channel activity. Results Microperfusion of etomidate into the thalamus elicited an increase in α-β frequency electrocortical activity that occurred only during non–rapid-eye-movement (REM) sleep (11.0 ± 11.8% and 16.0 ± 14.2% greater 8 to 12- and 12 to 30-Hz power, respectively; mean ± SD; both P < 0.031) and was not affected by blockade of thalamic T-type Ca2+ channels. Etomidate at the thalamus also increased spindle-like oscillations during non-REM sleep (4.5 ± 2.4 spindle per minute with etomidate vs. 3.2 ± 1.7 at baseline; P = 0.002). These effects of etomidate were fully recapitulated by enhanced thalamic extrasynaptic GABAAR-mediated spillover inhibition. Conclusions These findings identify how a prototypic GABAAR-targeting general anesthetic agent can elicit the characteristic brain wave pattern associated with anesthetic hypnosis when acting at the thalamus by promoting spillover inhibition and the necessity of a preexisting non-REM mode of activity in the thalamus to generate this effect.

As the number of international students studying at American universities continues to grow (Institute of International Education, 2014), campuses are increasingly becoming social spaces where the local, national, and international meet. Even though students’ identities may still be developing in college (Arnett, 2000) and their environment may influence their identity development (Erikson, 1968), little research has focused on the effects of this unique context on students’ identity formation. This study investigated the change in international and American student roommates’ ethnic and national identities over the course of one semester at three Midwestern universities. The qualitative results from semi-structured interviews with four undergraduate students suggest that these students were still grappling with their identities in different ways as they acted as discoverers, ambassadors, and negotiators and support a contextual approach to studying identity development in college students.

Background Drugs acting on μ-opioid receptors (MORs) are widely used as analgesics but present side effects including life-threatening respiratory depression. MORs are G-protein–coupled receptors inhibiting neuronal activity through calcium channels, adenylyl cyclase, and/or G-protein–gated inwardly rectifying potassium (GIRK) channels. The pathways underlying MOR-dependent inhibition of rhythmic breathing are unknown. Methods By using a combination of genetic, pharmacological, and physiological tools in rodents in vivo, the authors aimed to identify the role of GIRK channels in MOR-mediated inhibition of respiratory circuits. Results GIRK channels were expressed in the ventrolateral medulla, a neuronal population regulating rhythmic breathing, and GIRK channel activation with flupirtine reduced respiratory rate in rats (percentage of baseline rate in mean ± SD: 79.4 ± 7.4%, n = 7), wild-type mice (82.6 ± 3.8%, n = 3), but not in mice lacking the GIRK2 subunit, an integral subunit of neuronal GIRK channels (GIRK2−/−, 101.0 ± 1.9%, n = 3). Application of the MOR agonist [d-Ala2, N-MePhe4, Gly-ol]-enkephalin (DAMGO) to the ventrolateral medulla depressed respiratory rate, an effect partially reversed by the GIRK channel blocker Tertiapin-Q (baseline: 42.1 ± 7.4 breath/min, DAMGO: 26.1 ± 13.4 breath/min, Tertiapin-Q + DAMGO: 33.9 ± 9.8 breath/min, n = 4). Importantly, DAMGO applied to the ventrolateral medulla failed to reduce rhythmic breathing in GIRK2−/− mice (percentage of baseline rate: 103.2 ± 12.1%, n = 4), whereas it considerably reduced rate in wild-type mice (62.5 ± 17.7% of baseline, n = 4). Respiratory rate depression by systemic injection of the opioid analgesic fentanyl was markedly reduced in GIRK2−/− (percentage of baseline: 12.8 ± 15.8%, n = 5) compared with wild-type mice (72.9 ± 27.3%). Conclusions Overall, these results identify that GIRK channels contribute to respiratory inhibition by MOR, an essential step toward understanding respiratory depression by opioids.

Esophageal and gastric adenocarcinomas are frequently diagnosed at an advanced stage and have a dismal prognosis. Even in patients with potentially curative cancer, nearly 50% will develop recurrent disease despite aggressive treatments. A number of biomarkers currently guide treatment decisions for patients with esophageal and gastric adenocarcinoma and include human epidermal growth factor receptor 2 (HER2) amplification, mismatch repair deficiency/microsatellite instability (dMMR/MSI-H) and program death-ligand 1 (PD-L1) expression. This review will focus on the function, testing and FDA-approved targeted therapies for HER2, dMMR/MSI-H and PD-L1. In addition, a number of novel targets in esophageal and gastric cancer are being studied in clinical trials. Neurotrophic-tropomyosin receptor kinase (NTRK), claudin-18 (CLDN18)/Rho GTPase activating protein 26 (ARHGAP26) gene fusion, fibroblast growth factor receptor (FGFR), lymphocyte-activation gene 3 (LAG3) and T cell immunoglobulin and mucin-domain containing-3 (TIM3) will be briefly reviewed. Despite several biomarkers used in the selection of treatment therapies, treatment outcomes remain poor. Future research efforts will focus on the identification of new biomarkers, moving existing biomarkers into earlier lines of therapy, and evaluating new combinations of existing biomarkers and therapies.

BackgroundCritically ill patients with severe inflammation often exhibit heightened sensitivity to general anesthetics; however, the underlying mechanisms remain poorly understood. Inflammation increases the number of γ-aminobutyric acid type A (GABAA) receptors expressed on the surface of neurons, which supports the hypothesis that inflammation increases up-regulation of GABAA receptor activity by anesthetics, thereby enhancing the behavioral sensitivity to these drugs.MethodsTo mimic inflammation in vitro, cultured hippocampal and cortical neurons were pretreated with interleukin (IL)-1β. Whole cell patch clamp methods were used to record currents evoked by γ-aminobutyric acid (GABA) (0.5 μM) in the absence and presence of etomidate or isoflurane. To mimic inflammation in vivo, mice were treated with lipopolysaccharide, and several anesthetic-related behavioral endpoints were examined.ResultsIL-1β increased the amplitude of current evoked by GABA in combination with clinically relevant concentrations of either etomidate (3 μM) or isoflurane (250 μM) (n = 5 to 17, P < 0.05). Concentration–response plots for etomidate and isoflurane showed that IL-1β increased the maximal current 3.3-fold (n = 5 to 9) and 1.5-fold (n = 8 to 11), respectively (P < 0.05 for both), whereas the half-maximal effective concentrations were unchanged. Lipopolysaccharide enhanced the hypnotic properties of both etomidate and isoflurane. The immobilizing properties of etomidate, but not isoflurane, were also increased by lipopolysaccharide. Both lipopolysaccharide and etomidate impaired contextual fear memory.ConclusionsThese results provide proof-of-concept evidence that inflammation increases the sensitivity of neurons to general anesthetics. This increase in anesthetic up-regulation of GABAA receptor activity in vitro correlates with enhanced sensitivity for GABAA receptor–dependent behavioral endpoints in vivo.

The influence of specimen twisting during global anti-plane shear loading in composite split beam specimens is studied. Tests were conducted on specimens with different thicknesses and delamination lengths to produce different amounts of specimen twisting prior to fracture. It is shown that specimen twisting causes mode I stresses to develop, thereby producing mixed mode I–III conditions along the delamination front. This causes near-tip transverse cracks to initiate, prior to delamination advance, at an orientation related to the mode mix. Unlike in homogeneous materials, transverse crack extension is accompanied by planar delamination advance, and transverse crack rotation during extension is restricted by the laminate’s fibers. The overall fracture surface evolution is therefore strongly controlled by specimen geometry. The influence of these findings on the apparent delamination toughness as obtained from composite split beam and other types of mode III tests is discussed.

The three-dimensional evolution of a delamination and multiple coupled transverse cracks is studied in laminated tape composites using different mode III tests and specimens. All combinations produce 45° transverse cracks that initiate at the delamination front prior to delamination advance. For unidirectional laminates, the transverse crack length is governed by thickness, whereas for multidirectional laminates the transverse crack length is controlled by the ply angle and stacking sequence. These and other details of laminate architecture are shown to dictate the crack surface evolution, and provide distinguishing characteristics between the different laminates tested as well as in comparison to homogenous materials.

Basal forebrain cholinergic neurons are the main source of cortical acetylcholine, and their activation by histamine elicits cortical arousal. TWIK-like acid-sensitive K+(TASK) channels modulate neuronal excitability and are expressed on basal forebrain cholinergic neurons, but the role of TASK channels in the histamine-basal forebrain cholinergic arousal circuit is unknown. We first expressed TASK channel subunits and histamine Type 1 receptors in HEK cells. Application of histaminein vitroinhibited the acid-sensitive K+current, indicating a functionally coupled signaling mechanism. We then studied the role of TASK channels in modulating electrocortical activityin vivousing freely behaving wild-type (n= 12) and ChAT-Cre:TASKf/fmice (n= 12), the latter lacking TASK-1/3 channels on cholinergic neurons. TASK channel deletion on cholinergic neurons significantly altered endogenous electroencephalogram oscillations in multiple frequency bands. We then identified the effect of TASK channel deletion during microperfusion of histamine into the basal forebrain. In non-rapid eye movement sleep, TASK channel deletion on cholinergic neurons significantly attenuated the histamine-induced increase in 30–50 Hz activity, consistent with TASK channels contributing to histamine action on basal forebrain cholinergic neurons. In contrast, during active wakefulness, histamine significantly increased 30–50 Hz activity in ChAT-Cre:TASKf/fmice but not wild-type mice, showing that the histamine response depended upon the prevailing cortical arousal state. In summary, we identify TASK channel modulation in response to histamine receptor activationin vitro, as well as a role of TASK channels on cholinergic neurons in modulating endogenous oscillations in the electroencephalogram and the electrocortical response to histamine at the basal forebrainin vivo.SIGNIFICANCE STATEMENTAttentive states and cognitive function are associated with the generation of γ EEG activity. Basal forebrain cholinergic neurons are important modulators of cortical arousal and γ activity, and in this study we investigated the mechanism by which these neurons are activated by the wake-active neurotransmitter histamine. We found that histamine inhibited a class of K+leak channels called TASK channels and that deletion of TASK channels selectively on cholinergic neurons modulated baseline EEG activity as well as histamine-induced changes in γ activity. By identifying a discrete brain circuit where TASK channels can influence γ activity, these results represent new knowledge that enhances our understanding of how subcortical arousal systems may contribute to the generation of attentive states.

In this paper, an optimisation method is presented that turns the structural modes of an automotive-type panel into weak acoustic radiators. The advantage of the proposed method is that the optimum design does not depend upon a specific excitation mechanism. Hence, the optimised panel can be used in the early stages of vehicle product design when specific knowledge about the excitation forces is not available. In the proposed method the boundary conditions of the panel are specified such that the panel can be considered in isolation from the rest of the structure. The optimisation of the structural modes of the panel is then achieved by placing a number of constraint masses and stiffeners of optimum size and weight at optimum locations on the plate. Firstly, a theoretical model of a simply-supported plate is developed that takes into account the constraints at arbitrary positions and orientations. Then a genetic algorithm is used to minimise the sound power radiated by different modes on the plate by finding the optimum design for the constraints. Secondly, the use of added masses and stiffeners is then applied to a floor panel of a simplified model of a vehicle body structure in order to reduce the radiated sound. Predicted and experimental results of the radiated sound power from a reference flat panel and from various optimised panel designs are presented to illustrate the effectiveness of the optimised designs in reducing radiated sound from the structure. A combination of masses and stiffeners is shown to be an effective way of constructing weakly radiating structural modes on the panel.

Egg activation is the process by which a mature oocyte becomes capable of supporting embryo development. In vertebrates and echinoderms, activation is induced by fertilization. Molecules introduced into the egg by the sperm trigger progressive release of intracellular calcium stores in the oocyte. Calcium wave(s) spread through the oocyte and induce completion of meiosis, new macromolecular synthesis, and modification of the vitelline envelope to prevent polyspermy. However, arthropod eggs activate without fertilization: in the insects examined, eggs activate as they move through the female's reproductive tract. Here, we show that a calcium wave is, nevertheless, characteristic of egg activation in Drosophila. This calcium rise requires influx of calcium from the external environment and is induced as the egg is ovulated. Pressure on the oocyte (or swelling by the oocyte) can induce a calcium rise through the action of mechanosensitive ion channels. Visualization of calcium fluxes in activating eggs in oviducts shows a wave of increased calcium initiating at one or both oocyte poles and spreading across the oocyte. In vitro, waves also spread inward from oocyte pole(s). Wave propagation requires the IP3 system. Thus, although a fertilizing sperm is not necessary for egg activation in Drosophila, the characteristic of increased cytosolic calcium levels spreading through the egg is conserved. Because many downstream signaling effectors are conserved in Drosophila, this system offers the unique perspective of egg activation events due solely to maternal components.

Persistent and stable respiratory activity across behavioral states is key to homeostasis. Extrasynaptic δ-subunit containing GABAA receptors (δGABAARs) mediate tonic inhibition and regulate network activity. However, the influence of δGABAARs on respiratory rhythm and motor outputs is unknown. We manipulated extra-synaptic GABAA receptor function in the preBötzinger Complex (preBötC), a site central to the generation of inspiratory motor activity in mammals. Activation of preBötC δGABAARs in anesthetized rats and wild-type mice decreased breathing rate. In δGABAAR knockout (Gabrd −/−) mice, however, δGABAARs activation had no effect on breathing rate. We then found that during active wakefulness associated with behaviors and movements, diaphragm activation was higher in the Gabrd −/− compared to wild-type mice, but not in other states. These findings identify that δGABAARs modulate the respiratory network, which is critical to understand how δGABAARs change breathing in pathological conditions affecting extra-synaptic GABAA receptor function such as exposure to anesthetics and neurosteroids.

Reduced tongue muscle tone precipitates obstructive sleep apnea (OSA), and activation of the tongue musculature can lessen OSA. The hypoglossal motor nucleus (HMN) innervates the tongue muscles but there is no pharmacological agent currently able to selectively manipulate a channel (e.g., Kir2.4) that is highly restricted in its expression to cranial motor pools such as the HMN. To model the effect of manipulating such a restricted target, we introduced a “designer” receptor into the HMN and selectively modulated it with a “designer” drug. We used cre-dependent viral vectors (AAV8-hSyn-DIO-hM3Dq-mCherry) to transduce hypoglossal motoneurons of ChAT-Cre+ mice with hM3Dq (activating) receptors. We measured sleep and breathing in three conditions: (i) sham, (ii) after systemic administration of clozapine-N-oxide (CNO; 1 mg/kg) or (iii) vehicle. CNO activates hM3Dq receptors but is otherwise biologically inert. Systemic administration of CNO caused significant and sustained increases in tongue muscle activity in non-REM (261 ± 33% for 10 hrs) and REM sleep (217 ± 21% for 8 hrs), both P

Initial theories of rapid eye movement (REM) sleep generation posited that induction of the state required activation of the pontine subceruleus (SubC) by cholinergic inputs. Although the capacity of cholinergic neurotransmission to contribute to REM sleep generation has been established, the role of cholinergic inputs in the generation of REM sleep is ultimately undetermined as the critical test of this hypothesis (local blockade of SubC acetylcholine receptors) has not been rigorously performed. We used bilateral microdialysis in freely behaving rats (n= 32), instrumented for electroencephalographic and electromyographic recording, to locally manipulate neurotransmission in the SubC with select drugs. As predicted, combined microperfusion of D-AP5 (glutamate receptor antagonist) and muscimol (GABAAreceptor agonist) in the SubC virtually eliminated REM sleep. However, REM sleep was not reduced by scopolamine microperfusion in this same region, at a concentration capable of blocking the effects of cholinergic receptor stimulation. This result suggests that transmission of REM sleep drive to the SubC is acetylcholine-independent. Although SubC cholinergic inputs are not majorly involved in REM sleep generation, they may perform a minor function in the reinforcement of transitions into REM sleep, as evidenced by increases in non-REM-to-REM sleep transition duration and failure rate during cholinergic receptor blockade. Cholinergic receptor antagonism also attenuated the normal increase in hippocampal θ oscillations that characterize REM sleep. Using computational modeling, we show that ourin vivoresults are consistent with a mutually excitatory interaction between the SubC and cholinergic neurons where, importantly, cholinergic neuron activation is gated by SubC activity.

Extrasynaptic δ-subunits containing GABAAreceptors (δGABAARs) are sensitive targets for several commonly used hypnotic agents and mediate tonic neuronal inhibition. δGABAARs are highly expressed within the thalamus and their activation promotes a switch from tonic to burst firingin vitro. Here we test two hypothesesin vivo. (1) Activation of thalamic δGABAARs will elicit electrocortical signatures consistent with widespread thalamocortical burst firing such as increased delta oscillations (1–4 Hz) and reciprocal changes in spindle-like oscillations (7–14 Hz). (2) These signatures will be recapitulated by the general anesthetic etomidate, if the electrocortical effects of etomidate at the thalamus are mediated by δGABAARs. Microperfusion of the δGABAAR-preferring agonist 4,5,6,7-tetrahydroisoxazolo[5,4-c]pyridin-3-ol (THIP; 10 and 50 μm) into the ventrobasal complex produced significant effects on electrocortical activity in wild-type mice, but not in mice lacking δGABAARs (Gabrd−/−), i.e., the effects with THIP were dependent on δGABAARs. THIP (1) increased 1–4 Hz power in wakefulness and nonrapid-eye movement (NREM) sleep; (2) reduced spindle-like oscillations in NREM sleep; and (3) increased the speed of stable transitions into NREM sleep, indicating effects on state-space dynamics. In contrast, microperfusion of etomidate (10 and 30 μm) into the ventrobasal complex produced effects on electrocortical activity that were independent of δGABAARs, i.e., effects occurred in wild-type andGabrd−/−mice. Etomidate (1) decreased 1–4 Hz power, increased 8–12 Hz, and/or 12–30 Hz power in all sleep–wake states; (2) increased spindle-like oscillations; and (3) increased REM sleep expression. These results indicate that thalamic δGABAARs promote electrocortical signatures of deep NREM sleep, but do not mediate the effects of etomidate at the thalamusin vivo.

BackgroundThe risk of death is elevated in patients taking opioids for chronic non-cancer pain. Respiratory depression is the main cause of death due to opioids and sleep apnoea is an important associated risk factor.MethodsIn chronic pain clinics, we assessed the STOP-Bang questionnaire (a screening tool for sleep apnoea; Snoring, Tiredness, Observed apnoea, high blood Pressure, Body mass index, age, neck circumference and male gender), Epworth Sleepiness Scale, thyromental distance, Mallampati classification, daytime oxyhaemoglobin saturation (SpO2) and calculated daily morphine milligram equivalent (MME) approximations for each participant, and performed an inlaboratory polysomnogram. The primary objective was to determine the predictive factors for sleep apnoea in patients on chronic opioid therapy using multivariable logistic regression models.ResultsOf 332 consented participants, 204 underwent polysomnography, and 120 (58.8%) had sleep apnoea (AHI ≥5) (72% obstructive, 20% central and 8% indeterminate sleep apnoea), with a high prevalence of moderate (23.3%) and severe (30.8%) sleep apnoea. The STOP-Bang questionnaire and SpO2 are predictive factors for sleep apnoea (AHI ≥15) in patients on opioids for chronic pain. For each one-unit increase in the STOP-Bang score, the odds of moderate-to-severe sleep apnoea (AHI ≥15) increased by 70%, and for each 1% SpO2 decrease the odds increased by 33%. For each 10 mg MME increase, the odds of Central Apnoea Index ≥5 increased by 3%, and for each 1% SpO2 decrease the odds increased by 45%.ConclusionIn patients on opioids for chronic pain, the STOP-Bang questionnaire and daytime SpO2 are predictive factors for sleep apnoea, and MME and daytime SpO2 are predictive factors for Central Apnoea Index ≥5.Trial registration numberNCT02513836