Vitamin B12 deficiency causes a wide range of hematological, gastrointestinal, psychiatric and neurological disorders. Hematological presentation of cobalamin deficiency ranges from the incidental increase of mean corpuscular volume and neutrophil hypersegmentation to symptoms due to severe anemia, such as angor, dyspnea on exertion, fatigue or symptoms related to congestive heart failure, such as ankle edema, orthopnea and nocturia. Neuropsychiatric symptoms may precede hematologic signs and are represented by myelopathy, neuropathy, dementia and, less often, optic nerve atrophy. The spinal cord manifestation, subacute combined degeneration (SCD), is characterized by symmetric dysesthesia, disturbance of position sense and spastic paraparesis or tetraparesis. The most consistent MRI finding is a symmetrical abnormally increased T2 signal intensity confined to posterior or posterior and lateral columns in the cervical and thoracic spinal cord. Isolated peripheral neuropathy is less frequent, but likely overlooked. Vitamin B12 deficiency has been correlated negatively with cognitive functioning in healthy elderly subjects. Symptoms include slow mentation, memory impairment, attention deficits and dementia. Optic neuropathy occurs occasionally in adult patient. It is characterized by symmetric, painless and progressive visual loss. Parenteral replacement therapy should be started soon after the vitamin deficiency has been established.

The attraction of T lymphocytes into the pulmonary parenchyma represents an essential step in mechanisms ultimately leading to lung allograft rejection. In this study we evaluated whether IP-10 (CXCL10), a chemokine that is induced by interferon-gamma and stimulates the directional migration of activated T cells, plays a role in regulating the trafficking of effector T cells during lung allograft rejection episodes. Immunohistochemical examination showed that areas characterized by acute cellular rejection (grades 1 to 4) and active obliterative bronchiolitis (chronic rejection, Ca) were infiltrated by T cells expressing CXCR3, i.e., the specific receptor for CXCL10. In parallel, T cells accumulating in the bronchoalveolar lavage of lung transplant recipients with rejection episodes were CXCR3+ and exhibited a strong in vitro migratory capability in response to CXCL10. In lung biopsies, CXCL10 was abundantly expressed by graft-infiltrating macrophages and occasionally by epithelial cells. Alveolar macrophages expressed and secreted definite levels of CXCL10 capable of inducing chemotaxis of the CXCR3+ T-cell line 300-19; the secretory capability of alveolar macrophages was up-regulated by preincubation with interferon-gamma. Interestingly, striking levels of CXCR3 ligands could be demonstrated in the fluid component of the bronchoalveolar lavage in individuals with rejection episodes. These data indicate the role of the CXCR3/CXCL10 interactions in the recruitment of lymphocytes at sites of lung rejection and provide a rationale for the use of agents that block the CXCR3/CXCL10 axis in the treatment of lung allograft rejection.

Key Points• UDS demonstrated that BCR-ABL KD mutations detectable with conventional methods may just be the tip of the iceberg.• The information provided by conventional Sanger sequencing may not always be sufficient to predict responsiveness to a given TKI.In chronic myeloid leukemia and Philadelphia chromosome-positive acute lymphoblastic leukemia, tyrosine kinase inhibitor (TKI) therapy may select for drug-resistant BCR-ABL mutants. We used an ultra-deep sequencing (UDS) approach to resolve qualitatively and quantitatively the complexity of mutated populations surviving TKIs and to investigate their clonal structure and evolution over time in relation to therapeutic intervention. To this purpose, we performed a longitudinal analysis of 106 samples from 33 patients who had received sequential treatment with multiple TKIs and had experienced sequential relapses accompanied by selection of 1 or more TKI-resistant mutations. We found that conventional Sanger sequencing had misclassified or underestimated BCR-ABL mutation status in 55% of the samples, where mutations with 1% to 15% abundance were detected. A complex clonal texture was uncovered by clonal analysis of samples harboring multiple mutations and up to 13 different mutated populations were identified. The landscape of these mutated populations was found to be highly dynamic. The high degree of complexity uncovered by UDS indicates that conventional Sanger sequencing might be an inadequate tool to assess BCR-ABL kinase domain mutation status, which currently represents an important component of the therapeutic decision algorithms. Further evaluation of the clinical usefulness of UDS-based approaches is warranted. (Blood. 2013;122(9):1634-1648

IntroductionChemokines represent a group of molecules that regulate cell migration and can be distinguished in inflammatory and homeostatic chemokines. These latter are involved in the homeostasis of the immune system. [1][2][3][4][5][6][7][8] Cells are exposed to a complex pattern of chemoattractant signals that, through a gradient of chemokine concentrations, drive the migration of lymphocytes to target tissues or lymphoid organs. Different chemokine receptors are able to bind the same chemokine and, in turn, different chemokines are able to bind the same receptor, indicating that redundancy is a definite feature of the chemokine network. Chemokine-receptor interactions are of crucial importance for homeostatic functions within the immune system, particularly for establishing the complex architecture of the secondary lymphoid organs. 3,4,9 The role of chemokines for B-cell lymphopoiesis has been primarily demonstrated for CXCL12 (stromal-derived factor 1␣ ) and its receptor CXCR4. 10 CXCL12 can induce chemotaxis of B-cell progenitors, indicating that the CXCL12/ CXCR4 system may be important in directing the migration of B-cell progenitors to the appropriate bone marrow microenvironment. [11][12][13] In addition, it is highly expressed on B lymphocytes and it is likely to play a key role in the architecture of spleen and lymph nodes. To date, most information in terms of chemokines and their receptors has been provided on normal human B cells and in the mouse; little data are available on the role of these molecules on malignant B lymphocytes. [14][15][16][17] In particular, it has been demonstrated that malignant B cells express CXCR3 in different neoplastic conditions and mediate migration following the binding of the chemokines CXCL10 (inflammatory protein 10 [IP-10]) and CXCL9 (Mig). 14,16 Furthermore, CXCR4, a receptor constitutively expressed on normal B lymphocytes, has been detected on malignant B lymphocytes from patients with chronic lymphocytic leukemia (CLL). 15 In this study, we investigated the expression and functional role of a large spectrum of chemokine receptors, including CCR1 to CCR6 and CXCR1 to CXCR5, in several B-cell non-Hodgkin lymphomas (NHLs). We demonstrated that these receptors recognize different B-cell malignancies and mediate chemotaxis following binding to their own ligands. Patients, materials, and methods Patient samplesForty-three patients with different B-cell malignancies were studied at the time of diagnosis. 18 This study was approved by the Università of Padova institutional review board. Informed consent was provided according to the Declaration of Helsinki. Thirteen patients (10 men and 3 women, ages 46-78 years) with the diagnosis of B-CLL were graded according to the Rai staging system 19 Preparation of cell suspensionsPeripheral blood mononuclear cells (PBMCs) from patients with NHL were obtained from freshly heparinized blood samples by centrifugation on Ficoll/Hypaque (F/H) gradient. 20 Normal B lymphocytes were obtained from 5 tonsils after mechanic disruption...

Rationale: Acquisition of a procalcific phenotype by resident or circulating cells is important for calcification of atherosclerotic plaques, which is common in diabetes.Objective: We aim to identify and characterize circulating calcifying cells, and to delineate a pathophysiological role for these cells in type 2 diabetes. Methods and Results: