The use of antibiotics in the first year of life has been linked to asthma and other allergic diseases. The use of antibacterial cleaning products has also been associated with higher incidence of asthma, as has birth by Caesarean section rather than vaginal birth. Stress
Chronic stress can aggravate allergic conditions. This has been attributed to a T helper 2 (TH2)-predominant response driven by suppression of interleukin 12 by both the autonomic nervous system and the hypothalamic–pituitary–adrenal axis. Stress management in highly susceptible individuals may improve symptoms. Other environmental factors
Allergic diseases are more common in industrialized countries than in countries that are more traditional or agricultural, and there is a higher rate of allergic disease in urban populations versus rural populations, although these differences are becoming less defined. Historically, the trees planted in urban areas were predominantly male to prevent litter from seeds and fruits, but the high ratio of male trees causes high pollen counts, a phenomenon that horticulturist Tom Ogren has called "botanical sexism".Alterations in exposure to microorganisms is another plausible explanation, at present, for the increase in atopic allergy. Endotoxin exposure reduces release of inflammatory cytokines such as TNF-α, IFNγ, interleukin-10, and interleukin-12 from white blood cells (leukocytes) that circulate in the blood.
He linked ochronosis with the accumulation of alkaptans in 1902, and his views on the subject, including its mode of heritance, were summarized in a 1908 Croonian Lecture at the Royal College of Physicians. The genetics of it was also studied by William Bateson in the 1902.The defect was narrowed down to homogentisic acid oxidase deficiency in a study published in 1958. The genetic basis was elucidated in 1996, when HGD mutations were demonstrated.A 1977 study showed that an ochronotic Egyptian mummy had probably suffered from alkaptonuria. Research directions
Research collaborations by several national centres have been established to find a more definitive treatment for alkaptonuria. This has included studies on the use of nitisinone and investigations into antioxidants to inhibit ochronosis. The ideal treatment would replace HGD enzyme function without accumulating other substances. See also
List of cutaneous conditions
List of radiographic findings associated with cutaneous conditions

References


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