All parts of the jimsonweed plant are poisonous to horses and humans; toxicity is caused by tropane alkaloids. Symptoms of poisoning in horses include a weak, rapid pulse, dilated pupils, dry mouth, incoordination, diarrhea, convulsions, coma, and sometimes death.
Meningioma Causes. The causes of meningioma are not yet fully understood. In fact, several research studies suggest that many meningiomas develop spontaneously, or without a known cause. Sometimes, these tumors can disappear spontaneously as well. Meningiomas, like other solid tumors, develop when healthy cells undergo genetic mutations that cause them to replicate uncontrollably.
Meningiomas may cause seizures, headaches, and focal neurological defects, such as arm or leg weakness, or vision loss. Patients often have subtle symptoms for a long period before the meningioma is diagnosed. Sometimes memory loss, carelessness, and unsteadiness are the only symptoms.he only known predisposing factors associated with meningiomas are exposure to radiation, and certain genetic disorders (e.g. neurofibromatosis). Some have reported an association between meningiomas and the site of a previous injury (e.g. head trauma).