Given a question and a context passage, generate the answer having the word or phrase from the context passage. Here, the answer should be a shortest continous span from the passage.

[Q]: Context: Chronic lymphocytic leukemia (CLL) cells depend on microenvironmental factors for proliferation and survival. In particular, the B-cell receptor (BCR) and nuclear factor- B (NF-B) pathways are activated in the lymph node (LN) microenvironment. Thus, model systems mimicking tumor-host interactions are important tools to study CLL biology and pathogenesis. We investigated whether the recently established NOD/scid/c(null) (NSG) mouse xenograft model can recapitulate the effects of the human microenvironment. We assessed, therefore, tumor characteristics previously defined in LN-resident CLL cells, including proliferation, and activation of the BCR and NF-B pathways. We found that the murine spleen (SP) microenvironment supported CLL cell proliferation and activation to a similar degree than the human LN, including induction of BCR and NF-B signaling in the xenografted cells. Next, we used this model to study ibrutinib, a Bruton's tyrosine kinase inhibitor in clinical development. Ibrutinib inhibited BCR and NF-B signaling induced by the microenvironment, decreased proliferation, induced apoptosis and reduced the tumor burden in vivo. Thus, our data demonstrate that the SP of xenografted NSG mice can, in part, recapitulate the role of the human LN for CLL cells. In addition, we show that ibrutinib effectively disrupts tumor-host interactions essential for CLL cell proliferation and survival in vivo. 
 Question: What is the name of Bruton's tyrosine kinase inhibitor that can be used for treatment of chronic lymphocytic leukemia?
[A]: ibrutinib


[Q]: Context: To investigate whether gender is an independent factor associated with disease expression in early rheumatoid arthritis (RA) patients. 438 patients with early RA (disease duration less than one year) were studied. They all were patients with early RA who presented at the Rheumatology Clinic of the University Hospital of Ioannina during the period 1991-2000. All patients fulfilled the American College of Rheumatology criteria for RA. The demographic, clinical, laboratory, radiological and therapeutic characteristics of the disease at diagnosis, and at the last follow-up were analyzed according to gender. We studied 312 women and 126 men with early RA. The female to male ratio was 2.5:1 and the mean age at diagnosis was 49.4 +/- 14.9 years for women and 55.3 +/-15.6 years for men (P < 0.0003). Women had a longer duration of follow-up (P < 0.0003). There were no differences between genders in the general symptoms or the simmetricity of joint involvement at at disease onset. However at disease onset women had a higher erythrocyte sedimentation rate (ESR) (> 30 mm/1st hour), although there were no significant differences between the two groups concerninig the rest of the clinical, laboratory and radiological findings. At the last follow-up women still had a higher ESR (>30 min/1st hour), but no significant differences were found between the two groups concerning the rest of the parameters investigated independently of the follow-up duration. Finally, women and men showed the same degree of radiological changes and functional ability and were treated similarly except for the more frequent use of hydroxychloroquine in women. It seems that gender does not signficantly influence the expression of RA. 
 Question: Is Rheumatoid Arthritis more common in men or women?
[A]: women


[Q]: Context: Infectious Mononucleosis (IM), a benign lymphoproliferative disease, is the best known clinical syndrome caused by Epstein-Barr Virus (EBV). It usually resolves over a period of weeks or months without sequelae but may occasionally be complicated by a wide variety of neurologic, hematologic, hepatic, respiratory, and psychological complications. In this report we describe a patient with acute hepatitis following EBV-IM in a previously healthy woman. A 26-year-old woman who presented with fever, generalized weakness, nausea, sore throat, yellowing of skin, and a generalized skin rash was admitted to our clinic. Tonsillar enlargement, pharyngeal erythema, palatal petechiae, lymphadenopathy, and jaundice were noted. Significant atypical lymphocytes ( > 10%) were seen on the peripheral blood smear. Liver function tests such as ALT: 303 U/L, AST: 172 U/L, ALP: 193 U/L and total bilirubin: 7.3 mg/dl were elevated. Serological tests for EBV infection were consistent with acute infection (EBV virus capsid antigen was reactive with IgM and IgG antibodies). The Monospot test was also positive. On the seventh day, liver function tests and bilirubin had risen to peak level and platelets were decreased. The patient was managed supportively and her critical condition improved and was finally stabilized. Although the prognosis for IM is very favorable, a variety of acute complications may occur. 
 Question: Which virus can be diagnosed with the monospot test?
[A]:
epstein-barr virus