Claudins and Regulation of the Paracellular Transport System

Epithelia create barriers and regulate solute and water transport through transcellular and paracellular pathways. The paracellular pathways of different tissues vary remarkably in size selectivity, ionic charge selectivity and transepithelial electrical resistance (TER). The claudin family of transmembrane proteins is responsible for conferring these variable properties. In order to better understand the contribution of paracellular transport and claudins to the function of an epithelium, the properties conferred by cell-specific expression and localization of individual claudins need to be better understood. Here, we explore the properties of claudin- 14 and the localization pattern of claudins in the liver. Expression of human claudin- 14 significantly increases TER and decreases permeability to sodium. Quantitative PCR revealed hepatic expression of 9 of 16 claudins tested at levels varying as much as 700-fold. Immunofluorescent localization revealed localization of claudins- 1, -2 and -3 to hepatocytes, claudin-5 to endothelial cells, and claudins-3, -7 and -8 to cholangiocytes

Mo(3)Sb(7-x)Te(x) for Thermoelectric Power Generation

Compounds having compositions of Mo(3)Sb(7-x)Te(x) (where x = 1.5 or 1.6) have been investigated as candidate thermoelectric materials. These compounds are members of a class of semiconductors that includes previously known thermoelectric materials. All of these compounds have complex crystalline and electronic structures. Through selection of chemical compositions and processing conditions, it may be possible to alter the structures to enhance or optimize thermoelectric properties

The α2-adrenergic receptor agonist, clonidine, reduces alcohol drinking in alcohol-preferring (P) rats

Evidence suggests that noradrenergic signaling may play a role in mediating alcohol-drinking behavior in both rodents and humans. We have investigated this possibility by administering clonidine to alcohol-drinking rats selectively bred for alcohol preference (P line). Clonidine is an α2-adrenergic receptor agonist which, at low doses, inhibits noradrenergic signaling by decreasing norepinephrine release from presynaptic noradrenergic neurons. Adult male P rats were given 24-h access to food and water and scheduled access to a 15% (v/v) alcohol solution for 2 h daily. Rats received intraperitoneal (IP) injections with clonidine (0, 10, 20, 40, or 80 µg/kg body weight [BW], 10–11 rats/treatment group) once/day at 30 min prior to onset of the daily 2-h alcohol access period for 2 consecutive days. Clonidine, in doses of 40 or 80 µg/kg BW, significantly reduced alcohol intake on both days of treatment (p < 0.001). Two weeks later, rats were treated with clonidine for 5 consecutive days and clonidine, in doses of 40 or 80 µg/kg BW, reduced alcohol intake on all 5 treatment days (p < 0.001). Clonidine did not alter water consumption during the daily 2-h free-choice between alcohol and water. In a separate group of male P rats, clonidine (40 µg/kg BW) suppressed intake of a saccharin solution (0.04 g/L). These results are consistent with and complement our previous findings that the α1-adrenergic receptor antagonist, prazosin, decreases voluntary alcohol drinking in alcohol-preferring rats, but suggests that effects of clonidine may not be specific for alcohol. The results suggest that although activation of the noradrenergic system plays an important role in mediating voluntary alcohol drinking, care is needed in selecting which drugs to use to suppress central noradrenergic signaling in order to maximize the selectivity of the drugs for treating alcohol-use disorders

Regional and age differences in specialised palliative care for patients with pancreatic cancer

BACKGROUND: Despite national recommendations, disparities in specialised palliative care (SPC) admittance have been reported. The aims of this study were to characterize SPC admittance in patients with pancreatic cancer in relation to region of residence and age. METHOD: The data sources were two nationwide databases: Danish Pancreatic Cancer Database and Danish Palliative Care Database. The study population included patients (18+ years old) diagnosed with pancreatic cancer from 2011 to 2018. We investigated admittance to SPC, and time from diagnosis to referral to SPC and first contact with SPC to death by region of residence and age. RESULTS: In the study period (N = 5851) admittance to SPC increased from 44 to 63%. The time from diagnosis to referral to SPC increased in the study period and overall, the median time was 67 days: three times higher in Southern (92 days) than in North Denmark Region. The median number of days from diagnosis to referral to SPC was lower in patients ≥70 years (59 days) vs patients < 70 years (78 days), with regional differences between the age groups. Region of residence and age were associated with admittance to SPC; highest for patients in North Denmark Region vs Capital Region (OR = 2.03 (95%CI 1.67–2.48)) and for younger patients (< 60 years vs 80+ years) (OR = 2.54 (95%CI 2.05–3.15)). The median survival from admittance to SPC was 35 days: lowest in Southern (30 days) and highest in North Denmark Region (41 days). The median number of days from admittance to SPC to death was higher in patients < 70 years (40 days) vs ≥ 70 years (31 days), with a difference between age groups in the regions of 1–14 days. CONCLUSIONS: From 2011 to 2018 more patients with pancreatic cancer than previously were admitted to SPC, with marked differences between regions of residence and age groups. The persistently short period of time the patients are in SPC raises concern that early integrated palliative care is not fully integrated into the Danish healthcare system for patients with pancreatic cancer, with the risk that the referral comes so late that the patients do not receive the full benefit of the SPC

Cold and Slow Molecular Beam

Employing a two-stage cryogenic buffer gas cell, we produce a cold, hydrodynamically extracted beam of calcium monohydride molecules with a near effusive velocity distribution. Beam dynamics, thermalization and slowing are studied using laser spectroscopy. The key to this hybrid, effusive-like beam source is a "slowing cell" placed immediately after a hydrodynamic, cryogenic source [Patterson et al., J. Chem. Phys., 2007, 126, 154307]. The resulting CaH beams are created in two regimes. One modestly boosted beam has a forward velocity of vf = 65 m/s, a narrow velocity spread, and a flux of 10^9 molecules per pulse. The other has the slowest forward velocity of vf = 40 m/s, a longitudinal temperature of 3.6 K, and a flux of 5x10^8 molecules per pulse

Cigarette Smoke-induced Ca 2+ Release Leads to Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) Dysfunction

Chronic obstructive pulmonary disease affects 64 million people and is currently the fourth leading cause of death worldwide. Chronic obstructive pulmonary disease includes both emphysema and chronic bronchitis, and in the case of chronic bronchitis represents an inflammatory response of the airways that is associated with mucus hypersecretion and obstruction of small airways. Recently, it has emerged that exposure to cigarette smoke (CS) leads to an inhibition of the cystic fibrosis transmembrane conductance regulator (CFTR) Cl− channel, causing airway surface liquid dehydration, which may play a role in the development of chronic bronchitis. CS rapidly clears CFTR from the plasma membrane and causes it to be deposited into aggresome-like compartments. However, little is known about the mechanism(s) responsible for the internalization of CFTR following CS exposure. Our studies revealed that CS triggered a rise in cytoplasmic Ca2+ that may have emanated from lysosomes. Furthermore, chelation of cytoplasmic Ca2+, but not inhibition of protein kinases/phosphatases, prevented CS-induced CFTR internalization. The macrolide antibiotic bafilomycin A1 inhibited CS-induced Ca2+ release and prevented CFTR clearance from the plasma membrane, further linking cytoplasmic Ca2+ and CFTR internalization. We hypothesize that CS-induced Ca2+ release prevents normal sorting/degradation of CFTR and causes internalized CFTR to reroute to aggresomes. Our data provide mechanistic insight into the potentially deleterious effects of CS on airway epithelia and outline a hitherto unrecognized signaling event triggered by CS that may affect the long term transition of the lung into a hyper-inflammatory/dehydrated environment

Indecomposable Representations in Z_n Symmetric b,c Ghost Systems via Deformations of the Virasoro Field

The Virasoro field associated to b,c ghost systems with arbitrary integer spin lambda on an n-sheeted branched covering of the Riemann sphere is deformed. This leads to reducible but indecomposable representations, if the new Virasoro field acts on the space of states, enlarged by taking the tensor product over the different sheets of the surface. For lambda=1, proven LCFT structures are made explicit through this deformation. In the other cases, the existence of Jordan cells is ruled out in favour of a novel kind of indecomposable representations.Comment: 28 pages, 1 figure, uses empheq.sty, mhtools.sty, mhsetup.st