TASK DEFINITION: In this task, you are given a passage which has a question and the context. You have to generate an answer to the question based on the information present in the context.
PROBLEM: Context: Environmental conditions (eg, latitude) play a critical role in the susceptibility and severity of many autoimmune disorders, including multiple sclerosis (MS). Here, we investigated the mechanisms underlying the beneficial effects of immune regulatory processes induced in the skin by moderate ultraviolet B (UVB) radiation on central nervous system (CNS) autoimmunity.', 'Effects of UVB light were analyzed in a murine model of CNS autoimmunity (experimental autoimmune encephalomyelitis). Additionally, patients with relapsing-remitting MS were treated with narrowband UVB phototherapy. Immunomodulatory effects were examined in skin biopsies, serum samples, and immune cells of the peripheral blood.', 'Regulatory T cells (Tregs), which are induced locally in the skin-draining lymph nodes in response to UVB exposure, connect the cutaneous immune response to CNS immunity by migration to the sites of inflammation (blood, spleen, CNS). Here, they attenuate the inflammatory response and ameliorate disease symptoms. Treg-inducing tolerogenic dendritic cells (DCs) were further necessary for induction of this systemic immune regulation by UVB radiation, because ablation of Langerhans cells abolished the UVB-induced phenotype. MS patients treated with UVB phototherapy showed an increase in induced Tregs and tolerogenic DCs accompanied by the downregulation of the T-cell effector cytokine interleukin 21. The treatment further induced elevated serum levels of vitamin D.\Question: Does ultraviolet B light attenuate the systemic immune response in central nervous system autoimmunity?

SOLUTION: Local UVB radiation of the skin influences systemic immune reactions and attenuates systemic autoimmunity via the induction of skin-derived tolerogenic DCs and Tregs. Our data could have implications for the understanding or therapeutic modulation of environmental factors that influence immune tolerance.

PROBLEM: Context: Matrix metalloprotease-2 (MMP-2) and matrix metalloprotease-9 (MMP-9) play a key role in tissue remodelling after processes such as joint destruction in rheumatoid arthritis. Their expression may reflect the disease activity and they could therefore represent a useful marker to assess the efficacy of therapy. In this study MMP-2 and MMP-9 serum were evaluated in patients with chronic arthritis during therapy with the anti-TNFalpha mAb, infliximab.', 'Fifty patients with chronic arthritis, 26 with rheumatoid arthritis and 24 with undifferentiated chronic arthritis, were recruited and treated with infliximab (3 mg/kg). Serum concentrations of MMP-2 and MMP-9 were serially measured by gelatine zymography at baseline and after two and fourteen weeks of infliximab therapy. DAS-28 and ACR response criteria were applied to assess disease activity and clinical improvement. Twenty-four healthy donors were included in the study as controls.', 'Although therapy with infliximab induced a statistically significant reduction of the DAS-28 score and improvement of the ACR clinical response, MMP-2 and MMP-9 serum concentrations were not modulated during therapy with infliximab.\Question: Does infliximab therapy modify MMP-2 and MMP-9 serum concentrations in chronic arthritis?

SOLUTION: Our study provides further evidence that blocking TNFalpha by infliximab is a powerful tool in the management of chronic arthritis. Nevertheless, infliximab does not seem to be able to modify the serum expression of MMP-2 and MMP-9, probably because modification of these enzymes is restricted to the site of joint inflammation and serum detection can not truly mirror the local situation. Additional soluble factors correlating with joint damage should be investigated as possible markers for monitoring anti-TNFalpha therapy.

PROBLEM: Context: To investigate the prognostic value of weight loss before diagnosis in patients with advanced stage non-small cell lung cancer (NSCLC) treated with first-line chemotherapy.', 'A total of 81 NSCLC patients with stages IIIB/IV were included in this retrospective cross-sectional study. Study variables were weight loss in the last 3 months before diagnosis, patient demographic, clinical and laboratory characteristics and histological features of the tumor before administering first-line chemotherapy. Then, the patients were stratified into 4 groups based on their weight loss before being diagnosed with NSCLC.', 'The patients were predominantly male (68%), with a smoking history (62%), 5 to 10 kg weight loss in the last 3 months (31%), and had metastatic disease (64%) and adenocarcinoma (40%) at the time of diagnosis. On the other hand, most of the patients with 5 to 10 kg weight loss in the last 3 months before diagnosis had squamous cell carcinoma (44%), stage IV disease (56%), and the first disease progression was in the brain (64%). Pre-diagnosis weight loss had a negative impact on progression-free survival (PFS), independent from weight loss during first-line chemotherapy, but no such effect was noticed on overall survival (OS).\Question: Is weight loss at the time of diagnosis associated with prognosis in patients with advanced-stage non-small cell lung cancer?

SOLUTION:
Pre-diagnosis weight loss was found to have a negative impact on PFS in patients with NSCLC treated by first-line chemotherapy. Similar studies in larger patient series are warranted.