Über Hefegärung

Ohne Zusammenfassung     

Subunit Vaccines Consisting of Antigens from Dormant and Replicating Bacteria Show Promising Therapeutic Effect against Mycobacterium Bovis BCG Latent Infection

To screen effective antigens as therapeutic subunit vaccines against Mycobacterium latent infection, we did bioinformatics analysis and literature review to identify effective antigens and evaluated the immunogenicity of five antigens highly expressed in dormant bacteria, which included Rv2031c (HspX), Rv2626c (Hrp1), Rv2007c (FdxA), Rv1738 and Rv3130c. Then, several fusion proteins such as Rv2007c‐Rv2626c (F6), Rv2031c‐Rv1738‐Rv1733c (H83), ESAT6‐Rv1738‐Rv2626c (LT40), ESAT6‐Ag85B‐MPT64_<190‐198>‐Mtb8.4 (EAMM), and EAMM‐Rv2626c (LT70) were constructed and their therapeutic effects were evaluated in pulmonary Mycobacterium bovis Bacilli Calmette–Guérin (BCG) – latently infected rabbit or mouse models. The results showed that EAMM and F6 plus H83 had therapeutic effect against BCG latent infection in the rabbit model, respectively, and that the combination of EAMM with F6 plus H83 significantly reduced the bacterial load. In addition, the fusion proteins LT40 and LT70 consisting of multistage antigens showed promising therapeutic effects in the mouse model. We conclude that subunit vaccines consisting of both latency and replicating‐associated antigens show promising therapeutic effects in BCG latent infection animal models.     

Full-thickness human skin explants for testing the toxicity of topically applied chemicals

This report describes a model organ-culture system for testing the toxicity of chemical substances that are topically applied to human skin. In this system, the viable keratinocytes in the full-thickness skin explants are protected by the same keratinized layer as skin remaining on the donor, and toxicity can be assessed microscopically and/or biochemically. The human skin specimens were discards from a variety of surgical procedures. They were cut into full-thickness 1.0-cm2 explants, and briefly exposed to the military vesicant sulfur mustard (SM), which was used as a model toxicant. The explants were then organ cultured in small Petri dishes for 24 h at 36 degrees C. In the 0.03-1.0% dosage range, a straight-line dose-response relationship occurred between the concentration of SM applied and the number of paranuclear vacuoles seen histologically in the epidermis. Within the same SM dosage range, there was also a proportional decrease in 14C-leucine incorporation by the explants. Thus, the number of paranuclear vacuoles reflected decreases in protein synthesis by the injured epidermal cells. The epidermis of full-thickness untreated (control) human skin explants usually remained viable for 7 d when stored at 4 degrees C in culture medium. During storage, a relatively small number of paranuclear vacuoles developed within the epidermis, but the explants were still quite satisfactory for testing SM toxicity. Incubation (for 4 or 24 h at 36 degrees C) of such control skin explants reduced (often by 50%) the small number of paranuclear vacuoles produced during 4-7 d of storage. This reduction was probably caused by autolysis of many of the vacuolated cells. Two types of paranuclear vacuoles could be identified by both light and electron microscopy: a storage type and a toxicant type. The storage type seemed to be caused by autolysis of cell components. The toxicant type seemed to be caused by an invagination of the plasma membrane. Only toxicant-type vacuoles increased appreciably in number when skin explants were exposed to mustard, and to other toxicants.     

Frequent loss of 17p, but no p53 mutations or protein overexpression in benign and malignant pheochromocytomas.

Genetic changes in the tumorigenesis of sporadic pheochromocytomas are poorly understood, and there are no good markers to discriminate benign from malignant pheochromocytomas. p53 is a tumor suppressor gene and aberrations in this gene are frequently found in many tumor types. The role of p53 in pheochromocytoma tumorigenesis is unclear, with some studies suggesting that p53 mutations can be used to discriminate benign from malignant pheochromocytomas while other studies do not find such an association. Because most of these investigations were hampered by small series of tumors and the use of varying methods, we have performed a comprehensive analysis of p53 aberrations in a large series of pheochromocytomas. Comparative genomic hybridization analysis of 31 benign and 20 malignant tumors showed loss of the p53 locus at chromosome 17p13.1 in 23/51 (45%) cases, and most of these results were confirmed by fluorescence in situ hybridization. Forty-three tumors, including the malignant tumors and the tumors with loss of the p53 locus, were analyzed for p53 mutations in exons 5-8, but none were found. Furthermore, p53 immunohistochemistry on 35 cases revealed strong nuclear p53 expression in only two pheochromocytoma metastases, all other tumors being negative. We conclude that, although there is frequent loss of the p53 locus on 17p, the p53 gene does not appear to play a major role in pheochromocytoma tumorigenesis.     

Use of epidemiology in medical specialties: an examination by citation analysis

Epidemiologic methods have been applied unevenly among medical specialties. Identifying current uses and areas of potential research helps clarify and define the field. Using citation analysis of published data, the patterns of references to and by the American Journal of Epidemiology were examined for 1974-1982; 17,574 citations to and 15,872 citations by that Journal were classified according to the subject category of the referencing or referenced journal. Internal medicine and public health/epidemiology journals accounted for the largest proportion of all citations, followed by journals of immunology, cancer, microbiology, pediatrics, cardiovascular system, virology, tropical medicine, statistics, and obstetrics/gynecology. Few citations to or by the Journal were found in the allergy, anesthesiology, dermatology, geriatrics, hematology, nephrology, orthopedics, otorhinolaryngology, radiology, rheumatology, and urology journals. Examination of citations between clinical and epidemiologic literature suggests that adequate interchange between clinicians and epidemiologists is occurring. Citation analysis results for the American Journal of Epidemiology were significantly correlated (p less than 0.05) with those from a MEDLINE search on epidemiologic methods used in research in 22 clinical specialties. Despite inherent limitations, citation analysis appears to be a useful tool for examining interactions and trends in epidemiology and for identifying fields which may be ripe for new epidemiologic studies.     

Growing the field of health impact assessment in the United States: an agenda for research and practice

Health impact assessment (HIA) methods are used to evaluate the impact on health of policies and projects in community design, transportation planning, and other areas outside traditional public health concerns. At an October 2004 workshop, domestic and international experts explored issues associated with advancing the use of HIA methods by local health departments, planning commissions, and other decisionmakers in the United States.Workshop participants recommended conducting pilot tests of existing HIA tools, developing a database of health impacts of common projects and policies, developing resources for HIA use, building workforce capacity to conduct HIAs, and evaluating HIAs. HIA methods can influence decisionmakers to adjust policies and projects to maximize benefits and minimize harm to the public's health.     

Purification and Properties of the Cathepsin D Type Proteinase from Beef and Rabbit Lung and Its Identification in Macrophages

The acid-acting proteinase, cathepsin D (EC 3.4.4.23), was purified from extracts of homogenized rabbit lung and beef lung by autolysis at acid pH, acetone and ammonium sulfate fractionation, column chromatography, and isoelectric focusing. Four isoenzymes were obtained from each source. With acid hemoglobin as the substrate, the proteinase from rabbit lung had a pH optimum of 3.0 and that from beef lung had a pH optimum of 3.6. Their activity was not affected by thiol reagents or by Fe(2+), Mn(2+), or Mg(2+). One isoenzyme from rabbit lung was used to immunize a goat, and one from beef lung was used to immunize a rabbit. In immunoelectrophoresis, each resulting antiserum formed a single precipitin line with its homologous enzyme. They cross-reacted with the other three isoenzymes from the same species, but not with any isoenzyme from the other species. At high concentrations, each antiserum completely inhibited the proteolytic activity of its homologous enzyme. The antiserum against rabbit lung cathepsin D also inhibited the proteolytic activity of rabbit peritoneal and pulmonary macrophages. In limited quantities, this antiserum has now been made commercially available and is being used with labeled antibody techniques to identify under a microscope the presence of cathepsin D in macrophages and to study its role in the pathogenesis of tuberculosis.