Early increase in blood pressure and diastolic left ventricular malfunction in patients with glomerulonephritis

Early increase in blood pressure and diastolic left ventricular malfunction in patients with glomerulonephritis. In patients with diabetic nephropathy blood pressure increases progressively before the conventional threshold of normal blood pressure (140/90mm Hg) is transgressed. In patients with glomerulonephritis, no information on this point is available. To clarify this issue we sequentially examined 20 untreated patients with biopsy-proven primary chronic glomerulonephritis (GN) who had casual blood pressure below 140/90mm Hg and normal GFR by inulin clearance. Patients were compared with normotensive healthy controls who were matched for BMI, gender and age. We measured ambulatory 24-hour blood pressure (SpaceLab system), echocardiography (ASE criteria, Acuson 128 XP 10), CIn and CPAH, urinary Na excretion, PRA and insulin concentration. In patients with GN, the median 24 hour (P < 0.0005), daytime (P < 0.001) and nocturnal sleeping time (P < 0.0001) MAP values were significantly higher than in matched controls (daytime, mean 97mm Hg, 85 to 106 GN vs. 89 controls range 82 to 102; nocturnal sleeping time, mean 80.3mm Hg, 71 to 89.5 GN vs. 73 controls, range 63 to 84). Echocardiographic examination showed significantly greater posterior wall thickness (P < 0.01) and ventricular septal thickness (P < 0.003). In addition the early diastolic to late diastolic (E/A) ratio of mitral valve peak inflow velocity was significantly (P < 0.0008) lower in patients. The data point to left ventricular wall thickening accompanied by LV diastolic malfunction. The study documents elevated ambulatory blood pressure in patients with primary chronic glomerulonephritis despite normal body weight and normal GFR. This is associated with evidence of target organ damage in the heart. The findings suggest that in patients with glomerulonephritis blood pressure increases initially within the normotensive range. This observation in conjunction with evidence of early target organ changes provides an argument for early antihypertensive intervention, but controlled trials to test efficacy and safety of this proposal are necessary

On the fermionic T-duality of the AdS_4 \times CP^3 sigma-model

In this note we consider a fermionic T-duality of the coset realization of the type IIA sigma-model on AdS_4 \times CP^3 with respect to the three flat directions in AdS_4, six of the fermionic coordinates and three of the CP^3 directions. We show that the Buscher procedure fails as it leads to a singular transformation and discuss the result and its implications.Comment: LaTeX2e, 9 pages, no figures, JHEP style; v2: minor clarifications; v3: typos fixed, matches the published versio

Despite high levels of expression in thymic epithelial cells, miR-181a1 and miR-181b1 are not required for thymic development.

MicroRNAs (miRNAs) have been shown to be key modulators of post-transcriptional gene silencing in many cellular processes. In previous studies designed to understand the role of miRNAs in thymic development, we globally deleted miRNA exclusively in thymic epithelial cells (TECs), which are critical in thymic selection. This resulted in the loss of stromal cells that instruct T cell lineage commitment and affect thymocyte positive selection, required for mature T cell development. Since murine miR-181 is expressed in the thymus and miR-181 deficiency disrupts thymocyte development, we first quantified and thereby demonstrated that miR181a1 and miR181b1 are expressed in purified TECs. By generating mice with TEC targeted loss of miR-181a1 and miR-181b1 expression, we observed that neither TEC cellularity nor thymocyte number nor differentiation was adversely affected. Thus, disrupted thymopoiesis in miR-181 deficient mice was not due to miR-181 loss of expression in TECs. Importantly, in mice with restricted TEC deficiency of miR-181a1 and miR-181b1, there were similar numbers of mature T cells in the periphery in regards to frequencies, differentiation, and function as compared to controls. Moreover miR-181a1 and miR-181b1 were not required for maintenance of thymus integrity over time, as thymic involution was not accelerated in gene-targeted mice. Taken together our data indicate that miR-181a1 and miR-181b1 are dispensable for TEC differentiation, their control of thymocyte development and mature T cell export to and homeostasis within the periphery

Despite high levels of expression in thymic epithelial cells, miR-181a1 and miR-181b1 are not required for thymic development.

MicroRNAs (miRNAs) have been shown to be key modulators of post-transcriptional gene silencing in many cellular processes. In previous studies designed to understand the role of miRNAs in thymic development, we globally deleted miRNA exclusively in thymic epithelial cells (TECs), which are critical in thymic selection. This resulted in the loss of stromal cells that instruct T cell lineage commitment and affect thymocyte positive selection, required for mature T cell development. Since murine miR-181 is expressed in the thymus and miR-181 deficiency disrupts thymocyte development, we first quantified and thereby demonstrated that miR181a1 and miR181b1 are expressed in purified TECs. By generating mice with TEC targeted loss of miR-181a1 and miR-181b1 expression, we observed that neither TEC cellularity nor thymocyte number nor differentiation was adversely affected. Thus, disrupted thymopoiesis in miR-181 deficient mice was not due to miR-181 loss of expression in TECs. Importantly, in mice with restricted TEC deficiency of miR-181a1 and miR-181b1, there were similar numbers of mature T cells in the periphery in regards to frequencies, differentiation, and function as compared to controls. Moreover miR-181a1 and miR-181b1 were not required for maintenance of thymus integrity over time, as thymic involution was not accelerated in gene-targeted mice. Taken together our data indicate that miR-181a1 and miR-181b1 are dispensable for TEC differentiation, their control of thymocyte development and mature T cell export to and homeostasis within the periphery

Strings on Semisymmetric Superspaces

Several string backgrounds which arise in the AdS/CFT correspondence are described by integrable sigma-models. Their target space is always a Z(4) supercoset (a semi-symmetric superspace). Here we list all semi-symmetric cosets which have zero beta function and central charge c<=26 at one loop in perturbation theory.Comment: 25 pages, 1 figur

Evidence for the classical integrability of the complete AdS(4) x CP(3) superstring

We construct a zero-curvature Lax connection in a sub-sector of the superstring theory on AdS(4) x CP(3) which is not described by the OSp(6|4)/U(3) x SO(1,3) supercoset sigma-model. In this sub-sector worldsheet fermions associated to eight broken supersymmetries of the type IIA background are physical fields. As such, the prescription for the construction of the Lax connection based on the Z_4-automorphism of the isometry superalgebra OSp(6|4) does not do the job. So, to construct the Lax connection we have used an alternative method which nevertheless relies on the isometry of the target superspace and kappa-symmetry of the Green-Schwarz superstring.Comment: 1+26 pages; v2: minor typos corrected, acknowledgements adde

Light-like polygonal Wilson loops in 3d Chern-Simons and ABJM theory

We study light-like polygonal Wilson loops in three-dimensional Chern-Simons and ABJM theory to two-loop order. For both theories we demonstrate that the one-loop contribution to these correlators cancels. For pure Chern-Simons, we find that specific UV divergences arise from diagrams involving two cusps, implying the loss of finiteness and topological invariance at two-loop order. Studying those UV divergences we derive anomalous conformal Ward identities for n-cusped Wilson loops which restrict the finite part of the latter to conformally invariant functions. We also compute the four-cusp Wilson loop in ABJM theory to two-loop order and find that the result is remarkably similar to that of the corresponding Wilson loop in N=4 SYM. Finally, we speculate about the existence of a Wilson loop/scattering amplitude relation in ABJM theory.Comment: 37 pages, many figures; v2: references added, minor changes; v3: references added, sign error fixed and note adde

Integrability of Green-Schwarz Sigma Models with Boundaries

We construct integrability preserving boundary conditions for Green-Schwarz sigma-models on semi-symmetric spaces. The boundary conditions are expressed as gluing conditions of the flat-connection, using an involutive metric preserving automorphism. We show that the boundary conditions preserve half of the space-time supersymmetry and an infinite set of conserved charges. We find integrable D-brane configurations for AdS_5 x S^5 and AdS_4 x CP^3 backgrounds.Comment: 24 pages. v2 references added. v3 typos fixed, sec. 3 improved, references added, published versio

All one-loop amplitudes in N=6 superconformal Chern-Simons theory

We exploit a recently found connection between special triple-cut diagrams and tree-level recursive diagrams to derive a general formula capturing the multi-particle factorisation of arbitrary one-loop amplitudes in the ABJM theory. This formula contains certain anomalous contributions which are reminiscent of the so-called non-factorising contributions appearing in the factorisation of one-loop amplitudes in four-dimensional gauge theory. In the second part of the paper we derive a recursion relation for the supercoefficients of one-loop amplitudes in ABJM theory. By applying this recursion relation, any one-loop supercoefficient can be reduced to special triple-cut diagrams involving at least one four-point tree amplitude. In turn, this implies that any one-loop supercoefficient can be derived from tree-level recursive diagrams.Comment: 22 pages, 7 figure

Integrability, spin-chains and the AdS3/CFT2 correspondence

Building on arXiv:0912.1723, in this paper we investigate the AdS3/CFT2 correspondence using integrability techniques. We present an all-loop Bethe Ansatz (BA) for strings on AdS_3 x S^3 x S^3 x S^1, with symmetry D(2,1;alpha)^2, valid for all values of alpha. This construction relies on a novel, alpha-dependent generalisation of the Zhukovsky map. We investigate the weakly-coupled limit of this BA and of the all-loop BA for strings on AdS_3 x S^3 x T^4. We construct integrable short-range spin-chains and Hamiltonians that correspond to these weakly-coupled BAs. The spin-chains are alternating and homogenous, respectively. The alternating spin-chain can be regarded as giving some of the first hints about the unknown CFT2 dual to string theory on AdS_3 x S^3 x S^3 x S^1. We show that, in the alpha to 1 limit, the integrable structure of the D(2,1;alpha) model is non-singular and keeps track of not just massive but also massless modes. This provides a way of incorporating massless modes into the integrability machinery of the AdS3/CFT2 correspondence.Comment: LaTeX, 38 pages. v2: Corrected misprints in section 6.