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The quasar 3C279 was the target of an extensive multiwavelength monitoring campaign from January through April 2006, including an optical-IR-radio monitoring campaign by the Whole Earth Blazar Telescope (WEBT) collaboration. In this paper we focus on the results of the WEBT campaign. The source exhibited substantial variability of optical flux and spectral shape, with a characteristic time scale of a few days. The variability patterns throughout the optical BVRI bands were very closely correlated with each other. In intriguing contrast to other (in particular, BL Lac type) blazars, we find a lag of shorter- behind longer-wavelength variability throughout the RVB ranges, with a time delay increasing with increasing frequency. Spectral hardening during flares appears delayed with respect to a rising optical flux. This, in combination with the very steep IR-optical continuum spectral index of ~ 1.5 - 2.0, may indicate a highly oblique magnetic field configuration near the base of the jet. An alternative explanation through a slow (time scale of several days) acceleration mechanism would require an unusually low magnetic field of < 0.2 G, about an order of magnitude lower than inferred from previous analyses of simultaneous SEDs of 3C279 and other FSRQs with similar properties., Accepted for publication in ApJ

s / Biol Blood Marrow Transplant 19 (2013) S279eS312 S307 Medical Sciences, Tehran, Iran; 3 Immunology, Asthma, and Allergy Research Institute, Tehran University of Medical Sciences, Tehran, Iran; 4 Department of Pediatric Pathology, Mofid Children's Hospital, Shahid Beheshti University of Medical Sciences, Tehran, Iran Backkground: Hemophagocytic lymphohistiocytosis (HLH) is a life-threatening condition characterized by prolonged fever, hepatosplenomegaly, cytopenia, and hemophagocytosis. Primary HLH is considered fatal unless treated by hematopoietic stem cell transplantation (HSCT). Method: Herein we report six Iranian patients as a case series with primary HLH and their outcome from a single tertiary-care center Between 2000-2012. Results: Griscelli syndrome type 2 (GS2) was diagnosed in 3 patients based on clinical, laboratory, and microscopic features of partial albinism and finding of RAB27Amutations in 2 patients tested. Two patients were on the HLH-2004 continuation therapy and waiting for HSCT, but no matched donor yet: The first case is in 2nd remission after 1.5 years; he had history of relapse in maintenance phase of HLH-2004 protocol which more immunosuppressive treatment was advised. The second case is in remission after 1 year. Two other patients died, while waiting for a suitable donor: case 3 had history of recurrent HLH and died after 6 months; and the case 4 had history of progression to T-cell ALL after 2 years and dead due to relapse of ALL, sepsis and DIC despite chemotherapy after 3 years. Two patients underwent HSCT; patient 5 had a HLA-identical sibling donor and patient 6 had a cord blood-, unrelated, one antigen mismatched donor. Both patients were treated according to the HLH-2004 treatment protocol and none had active disease at the time of HSCT. Patient 5 who were diagnosed with GS2 responded well and remained in remission through 24 months of follow-up, while another case died because of graft-versushost disease and infection on day 136 after HSCT. Conclusion: HSCT seems to be the only curative treatment for primary HLH which drastically improve survival of the patients. Making a definite diagnosis confirmed by gene mutation studies is helpful to provide genetic counseling and prenatal diagnosis and, more important, dictate the need for HSCT later in the patient's course.