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.

[Q]: Context: Poor decision-making is a hallmark of addiction, whether to substances or activities. Performance on a widely used test of decision-making, the Iowa Gambling Task (IGT), can discriminate controls from persons with ventral medial frontal lesions, substance-dependence, and pathological gambling. Positron emission tomography (PET) studies indicate that substance-dependent individuals show altered prefrontal activity on the task. Here we adapted the IGT to an fMRI setting to test the hypothesis that defects in ventral medial and prefrontal processing are associated with impaired decisions that involve risk but may differ depending on whether substance dependence is comorbid with gambling problems.', '18 controls, 14 substance-dependent individuals (SD), and 16 SD with gambling problems (SDPG) underwent fMRI while performing a modified version of the IGT.', 'Group differences were observed in ventral medial frontal, right frontopolar, and superior frontal cortex during decision-making. Controls showed the greatest activity, followed by SDPG, followed by SD.\Question: Is prefrontal cortex activity reduced in gambling and nongambling substance users during decision-making?
[A]: Our results support a hypothesis that defects in ventral medial frontal processing lead to impaired decisions that involve risk. Reductions in right prefrontal activity during decision-making appear to be modulated by the presence of gambling problems and may reflect impaired working memory, stimulus reward valuation, or cue reactivity in substance-dependent individuals.


[Q]: Context: The aim of this study was to evaluate the characteristics of low-energy femoral insufficiency fractures in elderly patients.', 'The study retrospectively evaluated the clinical course of 4 patients with low-energy femoral shaft and subtrochanteric fractures admitted to our department between 2009 and 2011. Three patients had prior long-term alendronate therapy and one had prior glucocorticoid therapy.', 'There were 5 femoral shaft fractures, 2 incomplete shaft fractures, 2 subtrochanteric and 1 intertrochanteric fractures. All femoral shaft fractures had characteristic fracture patterns with thickened lateral cortices at the proximal fragment. Six femurs had excessive medial femoral bowing, which complicated intramedullary nailing. Additional fractures were seen on both femurs of one patient who had been primarily treated with short implants. A bifocal femoral fracture was seen in one femur. Union was achieved in all patients. Two patients were able to walk independently, one with a cane and one with double crutches.\Question: Does femoral insufficiency fractures in the elderly - excessive medial femoral bowing complicate intramedullary nailing?
[A]: We suggest the addition of another radiographic pattern of 'excessive medial femoral bowing' in low-energy femoral shaft fractures in elderly patients. This bowing complicates intramedullary nailing. Moreover, these insufficiency fractures should be fixed with long cephalomedullary nails.


[Q]: Context: The current paradigm suggests that matrix metalloproteinase 9 (MMP-9) expressed by stromal cells is a therapeutic target in human colorectal tumors which presumably regulates metastatic disease progression. Conversely, whereas cancer cells within those tumors may induce stromal cells to produce MMP-9 and may be targets for MMP-9 activity, they are not the source of MMP-9 underlying metastasis.', 'MMP-9 expression in matched colorectal tumors and normal adjacent mucosa from patients and human colon cancer cell lines was examined by real-time reverse transcription-PCR, laser capture microdissection, immunoelectron microscopy, and immunoblot analysis. The role of colon cancer cell MMP-9 in processes underlying metastasis was explored in vitro by examining degradation of extracellular matrix components by gelatin zymography and formation of locomotory organelles by cell spreading analysis and in vivo by quantifying hematogenous tumor cell seeding of mouse lungs.', 'Primary colorectal tumors overexpress MMP-9 compared with matched normal adjacent mucosa. In contrast to the current paradigm, MMP-9 is expressed equally by cancer and stromal cells within human colon tumors. Cancer cell MMP-9 regulates metastatic behavior in vitro, including degradation of extracellular matrix components and formation of locomotory organelles. Moreover, this MMP-9 critically regulates hematogenous seeding of mouse lungs by human colon cancer cells in vivo.\Question: Is tumor epithelial cell matrix metalloproteinase 9 a target for antimetastatic therapy in colorectal cancer?
[A]:
These observations reveal that MMP-9 produced by human colon cancer, rather than stromal, cells is central to processes underlying metastasis. They underscore the previously unrecognized potential of specifically targeting tumor cell MMP-9 in interventional strategies to reduce mortality from metastatic colorectal cancer.