The ion transporter Na⁺-K⁺-ATPase enables pathological B cell survival in the kidney microenvironment of lupus nephritis

The kidney is a comparatively hostile microenvironment characterized by highsodium concentrations; however, lymphocytes infiltrate and survive therein in autoimmune diseases such as lupus. The effects of sodium-lymphocyte interactions on tissue injury in autoimmune diseases and the mechanisms used by infiltrating lymphocytes to survive the highsodium environment of the kidney are not known. Here, we show that kidneyinfiltrating B cells in lupus adapt to elevated sodium concentrations and that expression of sodium potassium adenosine triphosphatase (Na+-K+-ATPase) correlates with the ability of infiltrating cells to survive. Pharmacological inhibition of Na+-K+-ATPase and genetic knockout of Na+-K+-ATPase γ subunit resulted in reduced B cell infiltration into kidneys and amelioration of proteinuria. B cells in human lupus nephritis biopsies also had high expression of Na+-K+-ATPase. Our study reveals that kidney-infiltrating B cells in lupus initiate a tissue adaption program in response to sodium stress and identifies Na+-K+-ATPase as an organ-specific therapeutic target

Evidence of non-extractable florfenicol residues: The development and validation of a confirmatory method for total florfenicol content in kidney by UPLC-MS/MS

Publication history: Accepted - 27 March 2016; Published online - 20 May 2016.The parent compound florfenicol (FF) is a broad-spectrum antibacterial compound licensed in the UK for use in cattle, pigs and the aquaculture industry. The analysis of porcine tissues in this study demonstrates that significant amounts of solvent non-extractable FF-related residues are present in incurred tissues (kidney and muscle) from treated animals. The results indicate that methods based on solvent extraction alone may carry a significant risk of reporting false-negative results. The use of a strong acid hydrolysis step prior to solvent extraction of tissue samples is necessary for an accurate estimate of the total tissue FF content. A robust and sensitive method for the determination of total FF residue content in kidney samples by ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) has been developed and validated. This method covers the synthetic amphenicol drug FF and its metabolites, measured as the marker residue florfenicol amine (FFA) as per Commission Regulation (EU) No. 37/2010. Non-extractable and intermediate metabolites are converted to the hydrolysis product FFA, and then partitioned into ethyl acetate. Extracts are solvent exchanged prior to a dispersive solid-phase extraction step, then analysed using an alkaline reverse-phase gradient separation by UPLC-MS/MS. The method was validated around the maximum residue levels (MRLs) set out in Regulation (EU) No. 37/2010 for bovine kidney in accordance with Commission Decision No. 2002/657/EC. The following method performance characteristics were assessed during a single laboratory validation study: selectivity, specificity, sensitivity, linearity, matrix effects, accuracy and precision (decision limit (CCα) and detection capability (CCβ) were determined)

Phosphatidylinositol 3-kinase (PI3K) pathway activation in bladder cancer

The phosphatidylinositol 3-kinase (PI3K) pathway is a critical signal transduction pathway that regulates multiple cellular functions. Aberrant activation of this pathway has been identified in a wide range of cancers. Several pathway components including AKT, PI3K and mTOR represent potential therapeutic targets and many small molecule inhibitors are in development or early clinical trials. The complex regulation of the pathway, together with the multiple mechanisms by which it can be activated, make this a highly challenging pathway to target. For successful inhibition, detailed molecular information on individual tumours will be required and it is already clear that different tumour types show distinct combinations of alterations. Recent results have identified alterations in pathway components PIK3CA, PTEN, AKT1 and TSC1 in bladder cancer, some of which are significantly related to tumour phenotype and clinical behaviour. Co-existence of alterations to several PI3K pathway genes in some bladder tumours indicates that these proteins may have functions that are not related solely to the known canonical pathway

New and resurrected Hawaiian species of pilo (Coprosma, Rubiaceae) from the island of Maui

Two species of Coprosma (Rubiaceae) J.R.Forst. & G.Forst. are described from the island of Maui of the Hawaiian Archipelago. A newly described taxon, Coprosma cordicarpa J.Cantley, Sporck-Koehler, & M.Chau,sp. nov. is locally common in medium to high elevation dry forests and shrublands of leeward East Maui. The second taxon is resurrected from the synonymy of C. foliosa A.Gray as C. stephanocarpa Hillebr. and occurs in mesic to wet rainforests of both East and West Maui. Both taxa are segregated from C. foliosa, with which they share similar morphological characters. A conspicuous and persistent calyx of the fruit and various floral characters most easily differentiate both taxa from other Hawaiian taxa. The newly describedCoprosma cordicarpa is further distinguished from C. stephanocarpa by a central constriction of the fruit with a depressed apex, which gives it a characteristic heart shape. Furthermore, the taxa are largely separated phenologically, ecologically, and geographically. Descriptions, conservation status, and specimens examined for the new species are included

Fine needle aspiration of salivary gland carcinomas with high‐grade transformation: A multi‐institutional study of 22 cases and review of the literature

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/167453/1/cncy22388_am.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/167453/2/cncy22388.pd

The intrinsic substrate specificity of the human tyrosine kinome.

Acknowledgements: We thank M. J. Begley, F. M. White, G. Getz, S. R. Hubbard, N. Shah and M. L. Hemming for discussions; and Y. Ma, M. R. Lundquist, K. Liberatore, T. M. Levy, S. A. Beausoleil, J. Wong, S. Petovic, M. Tran and the staff at Signalchem Biotech for technical assistance. T.M.Y.-B. thanks D. Yaron-Barir, S. Yaron, N. Yaron, J. R. Haddad and S. Haddad for their support. J.L.J. thanks M. Bak-Johnson, C. Ahn, S. Bak, J. W. Erickson and R. A. Cerione for their support. This research was supported by Leukemia & Lymphoma Society Award (to J.L.J. and L.C.C.); the Claudia Adams Barr Program for Cancer Research Award (to J.L.J.); National Institute of Health grants P01 CA120964 (to L.C.C.), R35-CA197588 (to L.C.C.), P01-CA117969 (to L.C.C.), R35-ES028374 (to M.B.Y.), R01-CA226898 (to M.B.Y.), R01-GM135331 (to B.E.T.) and R01-GM104047 (to B.E.T. and M.B.Y.); the joint Cancer Research UK and Brain Tumour Charity funded Brain Tumour Award C42454/A28596 (to M.B.Y.); the Charles and Marjorie Holloway Foundation (to M.B.Y.); the MIT Center for Precision Cancer Medicine (to M.B.Y.); the Jane Coffin Childs Memorial Fund (to J.M.O.); the Howard Hughes Medical Institute Hanna H. Gray Fellow award (to J.M.O.); and Cancer Research UK grants C9685/A26398 (to P.C.) and C9545/A29580 (to P.C.).Phosphorylation of proteins on tyrosine (Tyr) residues evolved in metazoan organisms as a mechanism of coordinating tissue growth1. Multicellular eukaryotes typically have more than 50 distinct protein Tyr kinases that catalyse the phosphorylation of thousands of Tyr residues throughout the proteome1-3. How a given Tyr kinase can phosphorylate a specific subset of proteins at unique Tyr sites is only partially understood4-7. Here we used combinatorial peptide arrays to profile the substrate sequence specificity of all human Tyr kinases. Globally, the Tyr kinases demonstrate considerable diversity in optimal patterns of residues surrounding the site of phosphorylation, revealing the functional organization of the human Tyr kinome by substrate motif preference. Using this information, Tyr kinases that are most compatible with phosphorylating any Tyr site can be identified. Analysis of mass spectrometry phosphoproteomic datasets using this compendium of kinase specificities accurately identifies specific Tyr kinases that are dysregulated in cells after stimulation with growth factors, treatment with anti-cancer drugs or expression of oncogenic variants. Furthermore, the topology of known Tyr signalling networks naturally emerged from a comparison of the sequence specificities of the Tyr kinases and the SH2 phosphotyrosine (pTyr)-binding domains. Finally we show that the intrinsic substrate specificity of Tyr kinases has remained fundamentally unchanged from worms to humans, suggesting that the fidelity between Tyr kinases and their protein substrate sequences has been maintained across hundreds of millions of years of evolution