Panel. Revisioning Miscegenation and Trauma in Faulkner and the African American South

Miscegenation and Progression: The First Americans of Jean Toomer and William Faulkner / Andrew Leiter, Lycoming CollegeNatasha Trethewey\u27s Joe Christmas and the Reconstruction of Mississippi Nativity / Ted Atkinson, Mississippi State UniversityContemporary Black Writing and Southern Social Belonging Beyond the Faulknerian Shadow of Loss / Lisa Hinrichsen, University of Arkansa

Neurogenin 3-expressing progenitor cells in the gastrointestinal tract differentiate into both endocrine and non-endocrine cell types

AbstractMice deficient for the transcription factor neurogenin 3 (ngn3) fail to develop endocrine cells in the intestine and pancreas and show partial endocrine differentiation in the stomach. We expressed Cre recombinase under control of a ngn3 BAC to achieve high fidelity cell lineage tracing in vivo to determine whether endocrine cells in these organs differentiate from NGN3+ precursor cells. Our results indicate that all small intestinal enteroendocrine cells arise from ngn3-expressing cells and confirm that NGN3+ cells give rise to all pancreatic endocrine cells as noted previously. By examining mice at a developmental stage when all of the cell types in the stomach have differentiated, we have delineated region-associated differences in endocrine differentiation. A much smaller fraction of endocrine cells populating the acid-producing region of the stomach is derived from NGN3+ precursor in contrast to the antral–pyloric region. Unexpectedly, ngn3 is expressed in cells that adopt non-endocrine cell fates including significant fractions of goblet and Paneth cells in the intestine and a small number of duct and acinar cells in the pancreas. Rarely, ngn3 was expressed in pluripotent cells in intestinal crypts with resultant labeling of an entire crypt–villus unit. Thus, ngn3 expression occurs in mixed populations of immature cells that are not irreversibly committed to endocrine differentiation

Intestinal Neurod1 expression impairs paneth cell differentiation and promotes enteroendocrine lineage specification

Transcription factor Neurod1 is required for enteroendocrine progenitor differentiation and maturation. Several earlier studies indicated that ectopic expression of Neurod1 converted non- neuronal cells into neurons. However, the functional consequence of ectopic Neurod1 expression has not been examined in the GI tract, and it is not known whether Neurod1 can similarly switch cell fates in the intestine. We generated a mouse line that would enable us to conditionally express Neurod1 in intestinal epithelial cells at different stages of differentiation. Forced expression of Neurod1 throughout intestinal epithelium increased the number of EECs as well as the expression of EE specific transcription factors and hormones. Furthermore, we observed a substantial reduction of Paneth cell marker expression, although the expressions of enterocyte-, tuft- and goblet-cell specific markers are largely not affected. Our earlier study indicated that Neurog3+ progenitor cells give rise to not only EECs but also Goblet and Paneth cells. Here we show that the conditional expression of Neurod1 restricts Neurog3+ progenitors to adopt Paneth cell fate, and promotes more pronounced EE cell differentiation, while such effects are not seen in more differentiated Neurod1+ cells. Together, our data suggest that forced expression of Neurod1 programs intestinal epithelial cells more towards an EE cell fate at the expense of the Paneth cell lineage and the effect ceases as cells mature to EE cells

Are post-treatment low-density lipoprotein subclass pattern analyses potentially misleading?

<p>Abstract</p> <p>Background</p> <p>Some patients administered cholesterol-lowering therapies may experience an increase in the proportion of small LDL particles, which may be misinterpreted as a worsening of atherosclerotic coronary heart disease risk. This study assessed the lipid effects of adding ezetimibe to atorvastatin or doubling the atorvastatin dose on low-density lipoprotein cholesterol (LDL-C) levels (and the cholesterol content of LDL subclasses), LDL particle number (approximated by apolipoprotein B), and LDL particle size. This was a multicenter, double-blind, randomized, parallel-group study of hypercholesterolemic, high atherosclerotic coronary heart disease risk patients. After stabilization of atorvastatin 40 mg, 579 patients with LDL-C >70 mg/dL were randomized to 6 weeks of ezetimibe + atorvastatin 40 mg or atorvastatin 80 mg. Efficacy parameters included changes from baseline in LDL-C, apolipoprotein B, non-high-density lipoprotein cholesterol (non-HDL-C), and lipoprotein subclasses (Vertical Auto Profile II) and pattern for the overall population, as well as patient subgroups with baseline triglyceride levels <150 mg/dL or ≥150 mg/dL.</p> <p>Results</p> <p>Both treatments significantly reduced LDL-C (and the cholesterol content of most LDL subfractions [LDL_1-4]) apolipoprotein B, non-HDL-C levels, but did not reduce the proportion of smaller, more dense LDL particles; in fact, the proportion of Pattern B was numerically increased. Results were generally similar in patients with triglyceride levels <150 or ≥150 mg/dL.</p> <p>Conclusions</p> <p>When assessing the effects of escalating cholesterol-lowering therapy, effects upon Pattern B alone to assess coronary heart disease risk may be misleading when interpreted without considerations of other lipid effects, such as reductions in LDL-C, atherogenic lipoprotein particle concentration, and non-HDL-C levels.</p> <p>Trial Registration</p> <p>(Registered at clinicaltrials.gov: Clinical trial # NCT00276484)</p

Nietzsche’s meta-axiology: against the skeptical readings

In this paper, I treat the question of the meta-axiological standing of Nietzsche's own values, in the service of which he criticizes morality. Does Nietzsche, I ask, regard his perfectionistic valorization of human excellence and cultural flourishing over other ideals to have genuine evaluative standing, in the sense of being correct, or at least adequate to a matter-of-fact? My goal in this paper is modest, but important: it is not to attribute to Nietzsche some sophisticated meta-axiological view, because I am doubtful that he has one. It is, however, to show that Nietzsche's texts do not necessitate the sceptical meta-axiological positions that have been attributed to him in the recent secondary literature. And it is thereby to suggest that we need not give up on the idea that Nietzsche takes the values he champions to have genuine evaluative standing – not because he has some sophisticated realist theory to this effect, but in a more philosophically unreflective way

Adenosine triphosphate is co-secreted with glucagon-like peptide-1 to modulate intestinal enterocytes and afferent neurons.

Enteroendocrine cells are specialised sensory cells located in the intestinal epithelium and generate signals in response to food ingestion. Whilst traditionally considered hormone-producing cells, there is evidence that they also initiate activity in the afferent vagus nerve and thereby signal directly to the brainstem. We investigate whether enteroendocrine L-cells, well known for their production of the incretin hormone glucagon-like peptide-1 (GLP-1), also release other neuro-transmitters/modulators. We demonstrate regulated ATP release by ATP measurements in cell supernatants and by using sniffer patches that generate electrical currents upon ATP exposure. Employing purinergic receptor antagonists, we demonstrate that evoked ATP release from L-cells triggers electrical responses in neighbouring enterocytes through P2Y2 and nodose ganglion neurones in co-cultures through P2X2/3-receptors. We conclude that L-cells co-secrete ATP together with GLP-1 and PYY, and that ATP acts as an additional signal triggering vagal activation and potentially synergising with the actions of locally elevated peptide hormone concentrations.Wellcome Trust joint investigator award (106262/Z/14/Z and 106263/Z/14/Z); MRC programme within the Metabolic Diseases Unit (MRC_MC_UU_12012/3); MRC Metabolic Diseases Unit [MRC_MC_UU_12012/5] ; Wellcome Trust Strategic Award [100574/Z/12/Z

A population of gut epithelial enterochromaffin cells is mechanosensitive and requires Piezo2 to convert force into serotonin release

Enterochromaffin (EC) cells constitute the largest population of intestinal epithelial enteroendocrine (EE) cells. EC cells are proposed to be specialized mechanosensory cells that release serotonin in response to epithelial forces, and thereby regulate intestinal fluid secretion. However, it is unknown whether EE and EC cells are directly mechanosensitive, and if so, what the molecular mechanism of their mechanosensitivity is. Consequently, the role of EE and EC cells in gastrointestinal mechanobiology is unclear. Piezo2 mechanosensitive ion channels are important for some specialized epithelial mechanosensors, and they are expressed in mouse and human EC cells. Here, we use EC and EE cell lineage tracing in multiple mouse models to show that Piezo2 is expressed in a subset of murine EE and EC cells, and it is distributed near serotonin vesicles by superresolution microscopy. Mechanical stimulation of a subset of isolated EE cells leads to a rapid inward ionic current, which is diminished by Piezo2 knockdown and channel inhibitors. In these mechanosensitive EE cells force leads to Piezo2-dependent intracellular Ca(2+) increase in isolated cells as well as in EE cells within intestinal organoids, and Piezo2-dependent mechanosensitive serotonin release in EC cells. Conditional knockout of intestinal epithelial Piezo2 results in a significant decrease in mechanically stimulated epithelial secretion. This study shows that a subset of primary EE and EC cells is mechanosensitive, uncovers Piezo2 as their primary mechanotransducer, defines the molecular mechanism of their mechanotransduction and mechanosensitive serotonin release, and establishes the role of epithelial Piezo2 mechanosensitive ion channels in regulation of intestinal physiology

Modeling the Influence of Vitamin D Deficiency on Cigarette Smoke-Induced Emphysema

Chronic obstructive pulmonary disease (COPD) is a major cause of morbidity and mortality worldwide. While the primary risk factor for COPD is cigarette smoke exposure, vitamin D deficiency has been epidemiologically implicated as a factor in the progressive development of COPD-associated emphysema. Because of difficulties inherent to studies involving multiple risk factors in the progression of COPD in humans, we developed a murine model in which to study the separate and combined effects of vitamin D deficiency and cigarette smoke exposure. During a 16-week period, mice were exposed to one of four conditions, control diet breathing room air (CD-NS), control diet with cigarette smoke exposure (CD-CSE), vitamin D deficient diet breathing room air (VDD-NS) or vitamin D deficient diet with cigarette smoke exposure (VDD-CSE). At the end of the exposure period, the lungs were examined by a pathologist and separately by morphometric analysis. In parallel experiments, mice were anesthetized for pulmonary function testing followed by sacrifice and analysis. Emphysema (determined by an increase in alveolar mean linear intercept length) was more severe in the VDD-CSE mice compared to control animals and animals exposed to VDD or CSE alone. The VDD-CSE and the CD-CSE mice had increased total lung capacity and increased static lung compliance. There was also a significant increase in the matrix metalloproteinase-9: tissue inhibitor of metalloproteinases-1 (TIMP-1) ratio in VDD-CSE mice compared with all controls. Alpha-1 antitrypsin (A1AT) expression was reduced in VDD-CSE mice as well. In summary, vitamin D deficiency, when combined with cigarette smoke exposure, seemed to accelerate the appearance of emphysemas, perhaps by virtue of an increased protease-antiprotease ratio in the combined VDD-CSE animals. These results support the value of our mouse model in the study of COPD

Acute Management and Outcomes of Patients with Diabetes Mellitus Presenting to Canadian Emergency Departments with Hypoglycemia

Objectifs: Cette vérification rétrospective des dossiers a permis d\u27examiner les données démographiques, les examens, la prise en charge et les résultats des patients adultes souffrant de diabète sucré qui se sont présentés aux services des urgences (SU) au Canada. Méthodes: Tous les sites ont mené une recherche dans leurs dossiers médicaux électroniques à l\u27aide des codes de la Classification internationale des maladies, dixième révision, pour relever les visites aux SU entre 2008 et 2010 qui étaient liées à l\u27hypoglycémie. Les caractéristiques des patients, les données démographiques, la prise en charge aux SU, les ressources des SU et les résultats sont rapportés. Résultats: Un total de 1039 patients de plus de 17 ans ont été inclus dans l\u27étude; 347 (33,4 %) ont été classifiés comme étant des cas de diabète de type 1 et 692 (66,6 %) ont été classifiés comme étant des cas de diabète de type 2. Les patients souffrant du diabète de type 2 étaient beaucoup plus âgés (73 ans vs 49 ans; p\u3c0,0001) et avaient plus d\u27affections chroniques inscrites à leur dossier (tous p\u3c0,001). La plupart des sujets arrivaient par ambulance, et 39 % des cas montraient des scores de triage qui révélaient des tableaux cliniques graves. Les traitements contre l\u27hypoglycémie étaient fréquents (75,7 %) durant le transport préhospitalier; 38,5 % recevaient du glucose et 40,1 % recevaient du glucagon par voie intraveineuse. Les traitements administrés dans les SU contre l\u27hypoglycémie comprenaient le glucose par voie orale (76,8 %), le glucose par voie intraveineuse (29,6 %) et en perfusion continue (27,7 %). Les examens diagnostiques (81,9 %) comprenaient fréquemment les électrocardiogrammes (51,9 %), la radiographie thoracique (37,5 %) et la tomodensitométrie crânienne (14,5 %). La plupart des patients (73,5 %) recevaient leur congé. Cependant, plus de sujets souffrant du diabète de type 2 nécessitaient une admission (30,3 vs 8,8 %). Les instructions de congé étaient étayées chez seulement 55,5 % des patients, et l\u27orientation vers des services de diabète se rencontrait chez moins de 20 % des cas. Une variation considérable dans la prise en charge de l\u27hypoglycémie existait entre les SU. Conclusions: Les patients souffrant de diabète qui se présentaient à un SU en raison d\u27une hypoglycémie consomment considérablement de ressources en soins de santé, puis une variation est observée dans la pratique. Les SU devraient élaborer des protocoles de prise en charge de l\u27hypoglycémie en portant une attention à la planification du congé pour réduire la récurrence