Large NN Phases of Chiral QCD_2

A matrix model is constructed which describes a chiral version of the large $N$ $U(N)$ gauge theory on a two-dimensional sphere of area $A$. This theory has three separate phases. The large area phase describes the associated chiral string theory. An exact expression for the free energy in the large area phase is used to derive a remarkably simple formula for the number of topologically inequivalent covering maps of a sphere with fixed branch points and degree $n$.Comment: 24 pgs., with 4 (postscript) figures included. MIT-CTP-230

Reduced selenium concentrations and glutathione peroxidase activity in preeclamptic pregnancies

Preeclampsia is a pregnancy-specific condition affecting 2-7% of women and a leading cause of perinatal and maternal morbidity and mortality. Preeclampsia may also predispose the fetus to increased risks of adult cardiovascular disease. Selenium, acting through the selenoprotein glutathione peroxidases, has critical roles in regulating antioxidant status. Recent reports implicate poor maternal selenium status as a nutritional factor predisposing the mother to preeclampsia but the fetus and placenta have not been studied in tandem. Measurement of selenium concentrations, expression and activity levels of glutathione peroxidase and markers of oxidative stress were performed on maternal and umbilical venous blood samples or the placenta from 27 normal pregnant, 25 preeclamptic and 22 healthy age-matched non-pregnant women. The results of this study revealed highly significant reductions in serum selenium concentrations and plasma glutathione peroxidase activity in pregnancy per se compared to non-pregnant controls. Moreover, these levels were further decreased in the preeclamptic mothers and babies compared to normal pregnancies. Umbilical venous selenium was particularly low (42.1±11.8 and 29.0 ± 9.9 mug/L; mean ±s.d.; P<0.05). Both mother and baby had significantly increased levels of markers for oxidative stress in the preeclamptic group. The placental glutathione peroxidase activity and immunohistochemical staining were also reduced in the preeclampsia placentae. Oxidative stress associated with preeclampsia may be a consequence of reduced antioxidant defence pathways specifically involving glutathione peroxidases, perhaps linked to reduced selenium availability. Reduced glutathione peroxidases could be associated with increased generation of toxic lipid peroxides contributing to the endothelial dysfunction and hypertension of preeclampsia

Nonmelanoma skin cancer in inflammatory bowel disease: A review

At least 1 million new cases of non-melanoma skin cancer (NMSC) are diagnosed in the United States each year, and the incidence is increasing. A higher incidence of non-melanoma skin cancer (NMSC) in organ transplant recipients on immunosuppression has been documented for some time, and recent studies indicate that patients with inflammatory bowel disease (IBD), particularly those treated with immunosuppressive medications, might also be at higher risk for this condition. In this review, we summarize recent data evaluating the associations between immunomodulators, anti-tumor necrosis factor-α (anti-TNF) biologic agents and NMSC in patients with IBD and other autoimmune conditions such as rheumatoid arthritis (RA). We also offer recommendations for prevention of NMSC in these populations

Risk of Melanoma and Nonmelanoma Skin Cancer Among Patients With Inflammatory Bowel Disease

Patients with inflammatory bowel disease (IBD) are at risk for certain malignancies. We aimed to determine the risk of melanoma and nonmelanoma skin cancer (NMSC) in patients with IBD and how medications affect these risks

Increased Risk for Non-Melanoma Skin Cancer in Patients With Inflammatory Bowel Disease

Patients with inflammatory bowel disease (IBD) might be at increased risk for certain malignancies. We evaluated the risk of non-melanoma skin cancer (NMSC) in patients with IBD and determined how immunosuppressive and biologic medications affect this risk

The effects of frequent nocturnal home hemodialysis: the Frequent Hemodialysis Network Nocturnal Trial

Prior small studies have shown multiple benefits of frequent nocturnal hemodialysis compared to conventional three times per week treatments. To study this further, we randomized 87 patients to three times per week conventional hemodialysis or to nocturnal hemodialysis six times per week, all with single-use high-flux dialyzers. The 45 patients in the frequent nocturnal arm had a 1.82-fold higher mean weekly stdKt/Vurea, a 1.74-fold higher average number of treatments per week, and a 2.45-fold higher average weekly treatment time than the 42 patients in the conventional arm. We did not find a significant effect of nocturnal hemodialysis for either of the two coprimary outcomes (death or left ventricular mass (measured by MRI) with a hazard ratio of 0.68, or of death or RAND Physical Health Composite with a hazard ratio of 0.91). Possible explanations for the left ventricular mass result include limited sample size and patient characteristics. Secondary outcomes included cognitive performance, self-reported depression, laboratory markers of nutrition, mineral metabolism and anemia, blood pressure and rates of hospitalization, and vascular access interventions. Patients in the nocturnal arm had improved control of hyperphosphatemia and hypertension, but no significant benefit among the other main secondary outcomes. There was a trend for increased vascular access events in the nocturnal arm. Thus, we were unable to demonstrate a definitive benefit of more frequent nocturnal hemodialysis for either coprimary outcome

Lambda and Antilambda polarization from deep inelastic muon scattering

We report results of the first measurements of Lambda and Antilambda polarization produced in deep inelastic polarized muon scattering on the nucleon. The results are consistent with an expected trend towards positive polarization with increasing x_F. The polarizations of Lambda and Antilambda appear to have opposite signs. A large negative polarization for Lambda at low positive x_F is observed and is not explained by existing models.A possible interpretation is presented.Comment: 9 pages, 2 figure

Shadowing in Inelastic Scattering of Muons on Carbon, Calcium and Lead at Low XBj

Nuclear shadowing is observed in the per-nucleon cross-sections of positive muons on carbon, calcium and lead as compared to deuterium. The data were taken by Fermilab experiment E665 using inelastically scattered muons of mean incident momentum 470 GeV/c. Cross-section ratios are presented in the kinematic region 0.0001 < XBj <0.56 and 0.1 < Q**2 < 80 GeVc. The data are consistent with no significant nu or Q**2 dependence at fixed XBj. As XBj decreases, the size of the shadowing effect, as well as its A dependence, are found to approach the corresponding measurements in photoproduction.Comment: 22 pages, incl. 6 figures, to be published in Z. Phys.

Collage Vol. II

JUDY COCHRAN: Editorial, 4-5 ROBERTA CHAPMEN: Photo, 6 ANITRA CHUGHTAI (Translations): Haikus, 7 CHARLES O\u27KEEFE: Photo, 8 MARK VANDERLINDE-ABERNATHY, ALYSSA LANDRY (Translator): Memories of a Spider (Les souvenirs d\u27une araignee), 9 MARK VANDERLINE-ABERNATHY, AMY NORSKOG (Translator): Tomato Fields (Champ de tomates), 10 SARAH BISHOP, HEFEDH ZANINA (Translator): Dear John (Cher John), 11 RYAN BUTZ (Translator): Basho\u27s Haiku, Issa\u27s Haiku, 12-13 JENNIFER HUMBERT, FADOUA EL BOUAMRAOUI (Translator): Pressed Lips (Levres Serrees), 15 ADELE REEVES (Translator): Contemporary song by Mr. Children, 16-17 BRODY PAGEL, GRACE DUGAR (Translator): The Lizard King (Le Roi Lezard), 18 JIMMY PIPKIN (Translator): In Love with You, 19 MOLLY ROSCOE: Saturday Night at Rusty\u27s (Samedi Soir a Rusty\u27s), 20 CHARLES O\u27KEEFE: Photo, 21 MATT MESSMER (Translator): Waseda University School Song, 22-23 TIMOTHY COOPER: Wenn du grosh bist… (When you\u27re Tall…), 24 DAVID HARMAN: Der Dunkle Stern (The Dark Star), 25 ANN TOWNSEND, JUDY COCHRAN (Translator): From a Window (D\u27une Fenetre), 26-27 SARA CAHILL: El sauce lloron (The Weeping Willow), 28-32 CHARLES O\u27KEEFE: Photo, 30 JENNIFER HUMBERT, MATT BISHOP: Past, Present (passe, present), 33 CAROL GENEYA KAPLAN, FADOUA EL BOUAMRAOUI (Translator): Une Autre Femme (Another Woman), 34-35 CHARLES O\u27KEEFE: Photo, 36 ANN TOWNSEND, JUDY COCHRAN (Translator): The Mowers (Les Faucheurs), 37 PRISCILLA PATON: Photo, 38 GONZALO TUESTA: La Grande Dame De Paris (The Great Lady of Paris), 39 SARAH PILLERDORF (Translator): Japanese Cartoons by Tezuka Osamu, 41-45 DANIELLE GERKEN: Schuhe der Heimat (Boots of Home), 47 CURTIS PLOWGIAN: Le peste de la langue francaise, 48-52 PRISCILLA PATON: Photo, 50 ZANE HOUSEHOLDER: Vive la Republique! (Film), 54 JENNIFER ZIMMER: EL tenis y las frustraciones (Tennis and Frustrations), La tumba de Ben (Ben\u27s Grave), 56-57 AUTUMN LOTZE: Times Square in the rain, 58-59 CHARLES O\u27KEEFE: Photo, 60 STEPHEN M. JULKA: Colors of the Earth, 61 THOMAS BRESSOUD: Java, 62 ERIC NELSON: World, 63 SARAH CLAPP (Translator): At a long day\u27s end (Natsume Soseki), A friend has come and is now leaving, Eating persimmons (Masaoka Shiki), 64 CHARLES O\u27KEEFE: Photo, 65 JOHN BURZYNSKI, MEGAN FETTER (Translator): Home is where the heart is, 66 RICHARD BANAHAN: Photo, 67 KIM FREEMAN: Baltimore, 68 JACOB RIDRIGUEZ-NOBLE: Home (Heimat), 69 SUZANNE KENNEDY: Oft verberge ich mich (Oft I hide myself), 70 RICHARD BANAHAN: Photo, 7

Dissociating Markers of Senescence and Protective Ability in Memory T Cells

No unique transcription factor or biomarker has been identified to reliably distinguish effector from memory T cells. Instead a set of surface markers including IL-7Rα and KLRG1 is commonly used to predict the potential of CD8 effector T cells to differentiate into memory cells. Similarly, these surface markers together with the tumor necrosis factor family member CD27 are frequently used to predict a memory T cell's ability to mount a recall response. Expression of these markers changes every time a memory cell is stimulated and repeated stimulation can lead to T cell senescence and loss of memory T cell responsiveness. This is a concern for prime–boost vaccine strategies which repeatedly stimulate T cells with the aim of increasing memory T cell frequency. The molecular cues that cause senescence are still unknown, but cell division history is likely to play a major role. We sought to dissect the roles of inflammation and cell division history in developing T cell senescence and their impact on the expression pattern of commonly used markers of senescence. We developed a system that allows priming of CD8 T cells with minimal inflammation and without acquisition of maximal effector function, such as granzyme expression, but a cell division history similar to priming with systemic inflammation. Memory cells derived from minimal effector T cells are fully functional upon rechallenge, have full access to non-lymphoid tissue and appear to be less senescent by phenotype upon rechallenge. However, we report here that these currently used biomarkers to measure senescence do not predict proliferative potential or protective ability, but merely reflect initial priming conditions