Their experiments on mice showed the virus impaired the ability of a specific part of the immune system, called regulatory T cells, to calm inflammation.

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But it wasn't known whether the trigger was mechanical ventilation or early inflammation due to gestational age, the authors of the latest study said.

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He went on the disabled list for three weeks because of a sprained ankle and didn't pitch after Aug. 17 because of lower back inflammation.

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Santana didn't pitch after Aug. 17 because of lower back inflammation.

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The T cells, Lieberburg says, seem to be the culprits behind the brain inflammation.

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"If a shoe doesn't support the arch, the fascia will be stretched, and that can cause inflammation, " says Robbins.

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In the end, these results can't be good for Merck, even though, as de Lemos points out, the inflammation idea is still just a hypothesis.

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