Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0034067 (emphysema)
 11,506 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We have examined the effect of the myeloperoxidase-hydrogen peroxide-halide system and of activated human neutrophils on the ability of serum alpha 1-protease inhibitor (alpha 1-PI) to bind and inhibit porcine pancreatic elastase. Exposure to the isolated myeloperoxidase system resulted in nearly complete inactivation of alpha 1-PI. Inactivation was rapid (10 to 20 s); required active myeloperoxidase, micromolar concentrations of H2O2 (or glucose oxidase as a peroxide generator), and a halide cofactor (Cl- or I-); and was blocked by azide, cyanide, and catalase. Intact neutrophils similarly inactivated alpha 1-PI over the course of 5 to 10 min. Inactivation required the neutrophils, a halide (Cl-), and a phorbol ester to activate secretory and metabolic activity. It was inhibited by azide, cyanide, and catalase, but not by superoxide dismutase. Neutrophils with absent myeloperoxidase or impaired oxidative metabolism (chronic granulomatous disease) failed to inactivate alpha 1-PI, and these defects were specifically corrected by the addition of myeloperoxidase or H2O2, respectively. Thus, stimulated neutrophils secrete myeloperoxidase and H2O2 which combine with a halide to inactivate alpha 1-PI. We suggest that leukocyte-derived oxidants, especially the myeloperoxidase system, may contribute to proteolytic tissue injury, for example in elastase-induced pulmonary emphysema, by oxidative inactivation of protective antiproteases.
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PMID:Myeloperoxidase-catalyzed inactivation of alpha 1-protease inhibitor by human neutrophils. 616 45

Electrosurgical techniques including laser surgery have expanded greatly in recent years. Pyrolysis of tissue produces smoke. Recently the smoke is being analyzed using Gas Chromatography-Mass Spectrometry. The nature of smoke depends on the rise of temperature of tissue during electro-surgery. The smoke produced at high temperatures contains low concentration of Group-I carcinogens (IARC) such as Benzene, Hydrogen cyanide, Formaldehyde 1,3-Butadiene and Acrylonitrile. Bioaerosol produced at low temperature as in harmonic scissors may contain live multidrug resistant Mycobacterium tuberculosis, viral DNA of HBV, HCV, HIV and HPV. It also contains live malignant cells and dead cellular materials. These produce an unquantified infection risk. The obnoxious smoke causes ocular and upper respiratory tract irritation, creates visual problems for surgeons. Surgical masks are not capable of filtering the produced bioaerosol. Removal of smoke from the site of operation by local exhaust ventilation is not complete. When produced in a closed cavity as in laparoscopic surgery the patient also suffers from carboxyhaemoglobinaemia and methaemoglobinaemia. Methemoglobinaemia is not detected by standard pulse-oximetry. Laser smoke produces congestive interstitial pneumonia, bronchiolitis and emphysema in rats. Chromosomal aberration and sister chromatid exchange have been found in lymphocyte culture of operating room personnel. Occupational safety and health authorities like Occupational Safety and Health Administration (OSHA), National Institute for Occupational safety and Health (NIOSH), American National Standard Institute (ANSI) and Association of Operating room nurses (AORN) are trying to find effective ways for removal of smoke from site of operation and also the real risk to operating room personnel. Answer lies in minimizing the use of electrocautery whenever possible and completes removal of harmful smoke.
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PMID:Electrosurgical smoke: a real concern. 2180 21