They're a more purposeful, laid back dog, in most cases, than Pitbulls tend to be. There are exceptions, examples of both lazier Pitbulls and the rare American Bulldog with an inordinate amount of energy, but even then, it's not nervous energy, and such exceptions in no way disprove the rule.
Anterior blepharitis is commonly caused by bacteria (staphyloccus blepharits) or dandruff of the scalp and eyebrows (seborrheic blepharitis). It may also occur due to a combination of factors, or less commonly may be the result of allergies or an infestation of lice on the eyelashes.
In many cases it is caused either by bacteria or by the skin condition known as seborrhea, which is similar to dandruff. Other times it is caused by severe allergies or plugged oil glands and rosacea. Although it is not as common, blepharitis can sometimes be caused by an infestation of the eyelashes by mites or lice.