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H M Sommers

Publications and source records attributed to H M Sommers.

8 recordsLinked to original sources
PubMed1979

Fortimicin A: collaborative in vitro susceptibility. Comparison with amikacin and gentamicin against 11,840 clinical bacterial isolates.

The susceptibility of 11,840 clinical bacterial isolates to fortimicin A was determined by agar dilution or broth microdilution methods and compared with their susceptibility to amikacin and gentamicin. In general, the in vitro activity of fortimicin A was essentially the same as that of amikacin. Significant exceptions were the increased effectiveness of fortimicin A against Serratia marcescens and the greater activity of amikacin against Pseudomonas and other nonfermentative gram-negative bacilli. On a weight-for-weight basis, gentamicin showed greater activity than the other two antimicrobial drugs against most species; S. Marcescens was the major exception. However, at concentrations equivalent to achievable nontoxic serum levels, the proportion of isolates inhibited by the three drugs was quite comparable. There were several strains with unusually high resistance to one or more of the tested antibiotics. These usually occurred in one of the six participating institutions and could be traced to specific enzyme-producing or permeability mutants endemic to that particular institution.

Amikacin↗
PubMed1978

Antibody activity in sera of patients with humidifier disease: studies of the water supply as a source of antigens.

In 5 patients with respiratory symptoms consistent with humidifier or air conditioner disease, a hypersensitivity pneumonitis, no identifiable organism was cultured from the humidifier water (HW). The water source to the humidifier or air conditioner was investigated for possible antigens which might explain the occurrence of the disease. Three subjects who lived in the same city supplied by Lake Michigan had increased IgG antibody activity against the city water supply when compared with another patient from a different city and a control subject. Both of the latter lived in cities with water supplied from Lake Michigan. Two of the 5 patients showed definite inhibition by concentrated tap water (TW) of IgG antibody against HW. The source of antigens in water was not determined but must be considered in cases of this type of hypersensitivity pneumonitis. A sixth case consistent with humidifier disease had Cephalosporium cultured from her HW. On gel diffusion there was a band of identity with her serum against Cephalosporium extract and her own HW, and by radioimmunoassay (RIA) there was over 50% inhibition of her IgG antibody activity against HW by Cephalosporium. No antibody against her city TW was demonstrated.

Acremonium↗
PubMed1977

Mitogen-induced lymphocyte and cutaneous reactions in dogs.

The lymphocyte response of dogs to mitogens was determined using separated lymphocyte and whole blood lymphocyte proliferation techniques. Reactivity to optimal doses of the following mitogens was demonstrated in decreasing order of intensity: phytohemagglutinin, Pokeweed mitogen, conconavalin A and sodium periodate. The canine cutaneous reactivity to these mitogens was also determined. Grossly, erythema and induration with all mitogens was maximal at 24 h. Microscopically, lesions using all mitogens consisted of edema, hyperemia and diffuse dermal infiltration with polymorphonuclear leukocytes and mononuclear cells. These mitogen-induced lesions may represent a specific lymphocyte-mediated inflammatory response, although a nonspecific reaction cannot be excluded.

Animals↗
PubMed1977

Immediate-type hypersensitivity to keyhole limpet haemocyanin in the dog.

A model of immediate-type hypersensitivity (ITH) in the dog using keyhole limpet haemocyanin (KLH) as the antigen was studied. Long-lasting ITH was induced in fifteen of sixteen dogs by the i.v. (Kepron & Tse, 1975), intradermal (Rockey, Schwartzmann & Halliwell, 1971), inhalation (Patterson & Kelley, 1974) and i.d. plus inhalation (Rockey et al., 1971) routes. This ITH was demonstrated by direct skin reactivity, acute respiratory reactions and peripheral blood leucocyte and respiratory cell histamine release. The reaginic antibodies considered to mediate these reactions were larger than canine IgG, heat labile, 2-mercaptoethanol sensitive, and are probably canine IgE. In addition to cutaneous and respiratory reactions, these reagins were shown to mediate systemic reactions. In the course of these studies, an unexpected finding was the occurrence of ITH to KLH in three dogs which had had no prior experimental exposure to KLH. This ITH was of sufficient intensity to be associated with acute airway reactions to the inhaled antigen.

Animals↗
PubMed1976

Results of the College of American Pathologists mycobacterial surveys, 1973.

Results of the College of American Pathologists Surveys showed a significant improvement of participant performances between 1972 and 1973. Participants in the Special Mycobacterial Survey did much better in speciating mycobacteria than did those in the Comprehensive Microbiology Survey. It is likely that many of the participants in the Comprehensive Microbiology Survey were unaware of their option to select the extent to which they offer service and were evaluated.

Bacteriological Techniques↗
PubMed1975

Laboratory services for mycobacterial diseases.

The philosophy of the recently proposed "Levels of Laboratory Service" program, which will be so vital to the conduct of a successful outpatient tuberculosis treatment and control program, is presented. The hallmark of this program is the decentralization of the diagnostic/monitoring services as they involve laboratory participation. In the long run this could mean more efficient operation, more reliable reporting, and probably less work for the participating laboratories. The greater emphasis on smear examination (Level I) as a monitoring tool will mean fewer cultures, thereby lessening the load for those laboratories that once went through countless clinically requested exercises of repetitively proving by culture the existence of M. tuberculosis in a given patient. Doubtless, the bulk of the work will be conducted in Level II laboratories; but here, too, identification of the most easily defined pathogen, M. tuberculosis, will minimize the over-all workload for these investigators while decreasing their concern about mycobacteria other than tubercle bacilli. Expertise gained in frequent repetitions of a limited number of tests (niacin, nitrate reduction, and pH 7/68 degrees C catalase) will ensure reliable speciation of the clinically most important Mycobacterium. The work of Level III laboratories should eventually be reduced primarily to organisms other than M. tuberculosis, thereby ensuring that a number of highly competent reference institutions will not only attain proficiency in taxonomic aspects of mycobacteria, but will also reflect the regional picture of the changing patterns in mycobacterial pathogens of man. Participation of laboratories in proficiency testing programs will encourage top-level performance in all areas. Additionally, such testing programs will serve a teaching role; a laboratory need not feel "locked in" at a given service level, but may increase its proficiency and move up a step in terms of the service it provides. In contrast, no laboratory need feel compelled to increase its activities; if daily workloads limit the extent of their involvement with mycobacteria, these laboratories can be confident that other institutions are providing needed services. The success of the entire "Levels of Laboratory Service" program depends on the recognition by individual laboratories of their own workload limitation, the directed motivation of personnel, and the maintenance of a free and open pipeline of communication to laboratories at the next higher level of service.

Bacteriological Techniques↗