December 6th, 2011 by Medgadget in Research
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Obesity is the most significant chronic healthcare crisis facing the United States, as well as other countries. Already 1 out of every 3 adults, and 1 out of every 6 children or adolescents, in the U.S. is obese! Leptin is a hormone that has received considerable attention since its discovery in 1994 for its role in regulating metabolism (like a thermostat, or adipostat) and implications for obesity. High leptin levels are associated with feeling satiated and an active metabolism. Though many overweight people have high levels of circulating leptin, it’s been found that their hypothalamic neurons do not receive the signal – a phenomenon known as “leptin resistance.” An animal model that mirrors this is db/db mice, which lack leptin receptors on the surface of they hypothalamic neurons and are therefore morbidly obese (see image).
Reporting in Science this past week, researchers at Harvard Medical School transplanted neurons with the leptin receptor into the hypothalami of db/db mice and as a result were able to partially restore leptin sensitivity and ameliorate their obesity. Two to three months after transplanting 15,000 (a relatively small number) fluorescently-tagged, leptin sensitive neurons into the db/db mice hypothalami, they observed statistically significant drops in blood sugar levels, leptin concentration, and fat mass. In terms of the mechanism and implications, the team concludes: Read more »
October 15th, 2011 by American Journal of Neuroradiology in Research
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Cerebral vasculitis is a known cause of ischemic and hemorrhagic strokes and has been described as one of the rare but important causes of corpus callosum infarction. Biopsy-proved giant cell arteritis causing callosal infarction is an exceedingly rare finding because a tissue specimen is usually not obtained and conclusions are drawn on the basis of clinical and radiologic findings alone. We present a case of callosal infarction, which evolved and eventually affected large portions of both cerebral hemispheres.
A 63-year-old woman presented to our hospital with left-sided numbness and neglect, cognitive changes, and apraxia. One month earlier, she was found to have a C-reactive protein level of 8.0 mg/dL (normal <0.5 mg/dL) and 75% stenosis in both femoral arteries. These results prompted Read more »
*This blog post was originally published at AJNR Blog*
October 11th, 2011 by Berci in Opinion
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This is one of the best pictures I’ve ever seen. I’m almost totally a left brain… What about you?
Left brain: I am the left brain. I am a scientist. A mathematician. I love the familiar. I categorize. I am accurate. Linear. Analytical. Strategic. I am practical. Always in control. A master of words and language. Realistic. I calculate equations and play with numbers. I am order. I am logic. I know exactly who I am.
Right brain: I am the right brain. I am creativity. A free spirit. I am passion. Yearning. Sensuality. I am the sound of roaring laughter. I am taste. The feeling of sand beneath bare feat. I am movement. Vivid colors. I am the urge to paint on an empty canvas. I am boundless imagination. Art. Poetry. I sense. I feel. I am everything I wanted to be.
*This blog post was originally published at ScienceRoll*
September 27th, 2011 by Edwin Leap, M.D. in Health Policy, Opinion
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I recently saw a teenage boy with headaches. His father, wringing his hands, said that the headaches had been present for two years; but that the child had never been evaluated for them. No imaging, no neurologist. No insurance, of course.
A family friend, another child, had been diagnosed with a brain tumor. The family of my patient was terrified. Where to turn? They were, reasonably, concerned about cost.
Contrast that with the woman I saw on state assistance. Read more »
*This blog post was originally published at edwinleap.com*
August 20th, 2011 by American Journal of Neuroradiology in Research
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Bilateral symmetric claustrum lesions shown on MR imaging are rarely reported, especially transient and reversible lesions associated with seizures, such as herpes simplex encephalitis,1 unidentified encephalopathy,2 and acute encephalitis with refractory repetitive partial seizures.3 To our knowledge, there are no reports of symmetric bilateral claustrum lesions with mumps encephalitis.
A 21-year-old man had been experiencing cold like symptoms with headache and fever for a week when he vomited and had a tonic-clonic seizure and was subsequently taken to a nearby emergency hospital (day 1). He had been noticing spasms on the left side of his face for 2 days. On his last visit to the hospital, he reported disorientation accompanied by fever; however, a brain MR imaging and CSF analysis showed no abnormalities. Because he was instatus epilepticus on hospitalization, midazolam was administered by intravenous infusion at 3.0 mg/h. Around this time, the patient started to experience visual hallucinations and reported seeing Read more »
*This blog post was originally published at AJNR Blog*
