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.
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Question: Context: Progress in the management of patients with medically intractable epilepsy is impeded because we do not fully understand why pharmacoresistance happens and how it can be predicted. The presence of multiple seizures prior to medical treatment has been suggested as a potential predictor of poor outcome. In the present study, we used an animal model of temporal lobe epilepsy to investigate whether pharmacoresistant rats differ in seizure frequency from pharmacoresponsive animals.', 'Epilepsy with spontaneous recurrent seizures (SRS) was induced by status epilepticus. Frequency of SRS was determined by video/EEG (electroencephalography) monitoring in a total of 33 epileptic rats before onset of treatment with phenobarbital (PB).', 'Thirteen (39%) rats did not respond to treatment with PB. Before treatment with PB, average seizure frequency in PB nonresponders was significantly higher than seizure frequency in responders, which, however, was due to six nonresponders that exhibited > 3 seizures per day. Such high seizure frequency was not observed in responders, demonstrating that high seizure frequency predicts pharmacoresistance in this model, but does not occur in all nonresponders.\Question: Is high seizure frequency prior to antiepileptic treatment a predictor of pharmacoresistant epilepsy in a rat model of temporal lobe epilepsy?

Answer: The data from this study are in line with clinical experience that the frequency of seizures in the early phase of epilepsy is a dominant risk factor that predicts refractoriness. However, resistance to treatment also occurred in rats that did not differ in seizure frequency from responders, indicating that disease severity alone is not sufficient to explain antiepileptic drug (AED) resistance. These data provide further evidence that epilepsy models are useful in the search for predictors and mechanisms of pharmacoresistance.


Question: 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?

Answer: 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.


Question: Context: Tibial bones are shorter and less resistant to shear forces after treatment with doxorubicin, methotrexate, or cisplatin. We investigated the pattern of failure after shear loading of the proximal tibial growth plate in rats treated with these chemotherapeutic agents.', 'Male Wistar rats from the age of 4 weeks were given doxorubicin intravenously at 15 mg/m2 body surface area (BSA), methotrexate 60 mg/m2 BSA, or cisplatin 7.5 mg/m2 BSA. There was one nontreated control group fed ad libitum an d a diet control group for each drug-treated group. At the age of 13 weeks the tibial bones were dissected. The proximal growth plate was shear loaded to failure in the posteroanterior direction. The pattern of failure through the growth plate was examined.', 'In rats fed ad libitum the failure pattern ran mainly through the transitional zone between proliferating and hypertrophic chondrocytes, but the pattern of failure showed considerable variability. The pattern in rats treated with methotrexate or cisplatin and that in their diet controls were comparable. In rats treated with doxorubicin the fracture ran mainly through the trabecular zone.\Question: Does chemotherapy affect the pattern of failure after shear loading of the proximal tibial growth plate?

Answer:
Doxorubicin affects the pattern of failure after shear loading of the proximal tibial growth plate, but methotrexate and cisplatin do not. Special attention should be paid to epiphyseal injuries in children treated with doxorubicin.