Measurement of bacterial and fungal contributions to respiration of selected agricultural and forest soils

A technique using selective inhibitors was used to estimate the relative contributions of bacterial and fungal populations to the respiration of six soils and one litter sample. The ratios of bacterial to fungal respiration in the four agricultural soils, given in percentage of the total microbial activity, ranged from 10/90 to 35/65, with the average ratio being about 30/70. In the forest soils, the ratios were 20/80 and 30/70, and in a beech litter sample, the ratio was 40/60. The fungi clearly dominated in all samples. The ratios were not found to be pH related. The difficulties which had previously limited the use of selective inhibitors for in situ soil ecological investigations, such as insufficient inhibitor specificity, inhibitor inactivation or degradation, and errors of measurement caused by elimination of competitor populations, were either resolved or methodologically avoided in the experiments. Inhibitor selectivity was demonstrated using both mixed and pure cultures of microorganisms from each soil. Through the use of experiments with short incubation periods (6-8 h), problems with population shifts and inhibitor degradation were eliminated.

Ornithosis in Somerset. Experience in the South Somerset clinical area 1964-71

During an 8-year period, seventy patients were found, by complement fixation testing, to have had ornithosis. A clinical analysis was made of forty-seven who fulfilled strict diagnostic criteria; thirty-three had been referred to a chest clinic, fourteen had been hospitalized. A non-specific, febrile, myalgic illness with respiratory symptoms was the usual clinical syndrome; cough was a prominent, often dramatic, symptom. Pulmonary crepitations, variable radiographic changes, and a normal white blood cell count were found to be useful diagnostic features. Ornithosis sometimes masqueraded as major chest disease, and could be debilitating. Careful retrospective interrogation revealed significant bird contacts in the majority of patients. Treatment with a tetracycline was of possible clinical benefit.

Method for Simultaneous Measurement of Radioactive and Inactive CO 2 Evolved from Soil Samples During Incubation with Labeled Substrates

An apparatus is described which allows the simultaneous, continuous, and highly sensitive analysis of inactive and radioactive CO 2 evolved from 14 C-supplemented soils or other materials. The apparatus consists of a control unit, a commercially available conductometric CO 2 analyzer, and fraction collector. A number of model experiments were conducted to demonstrate the potentials of the apparatus. These included analysis of the time course of priming action, when 14 C-glucose was added to soil, separation of CO 2 respiration peaks caused by simultaneous degradation of radioactive and inactive soil supplements, and study of the effects of a fungicide, Benomyl, on degradation of 14 C-labeled glucose. In the last experiment, partial degradation of the fungicide could also be followed.

Effects of various soil fungi and insecticides on the capacity of Mucor alternans to degrade DDT

Pure cultures of the fungus Mucor alternans, isolated from DDT-contaminated soils, were able to degrade DDT to water-soluble metabolites. After the addition of fungal spores to DDT-contaminated soils, however, the insecticide-degrading capacity of the fungus was no longer evident. Since under field conditions many species of fungi are simultaneously exposed to mixed residues of pesticidal chemicals, the effects of various species of soil fungi and of various insecticides on DDT degradation by M. alternans were investigated. Experiments were conducted to study the effect of nine fungal species, their stale cell-free media, and various insecticides and related compounds on the capacity of M. alternans to degrade 14C-DDT to water-soluble metabolites. It was found that several pure fungal cultures or some cell-free media, in which mycelia had grown, could also degrade the insecticide. In most cases, however, addition of one of the various fungi to 14C-DDT-treated M. alternans cultures resulted in a total depression of the appearance of water-soluble metabolites in the media. This was due to an accumulation of the metabolites in the mycelium of the other fungus or in an inhibition of metabolite formation. Addition of stale media from various fungi to 14C-DDT-treated M. alternans cultures had various effects on fungal growth and on the capacity of the fungus to degrade the insecticide. Among the insecticides and related compounds tested only lindane, parathion, and Dyfonate caused a reduction in DDT degradation by M. alternans, without severely reducing its vegetative growth.

Effect of nutritional factors on DDT-degradation by Mucor alternans

The effects of nutritional factors on the capacity of Mucor alternans to degrade 14C-DDT in shake cultures were investigated. Fungal spores did not grow in media that contained DDT as the sole carbon source, but they remained viable over a 2-month period and developed into a mycelium, once glucose had been added. The degradation of DDT by the fungus was not related to the mycelial mass. The quantity of water-soluble metabolites produced from DDT was, to some extent, dependent on the insecticide concentration, but largely on the carbon and nitrogen sources in the culture media. Largest quantities of the metabolites were formed with glucose and ammonium nitrate. The concentration of glucose affected this metabolism quantitatively. With the exception of ribose, growth on other sugars resulted in a decrease in the production of DDT-metabolites, which was most noticeable when maltose was used. No qualitative differences in the metabolites were observed. When ammonium nitrate was replaced with other nitrogen sources, the production of water-soluble metabolites was substantially reduced (35 to 75%) and qualitative differences in the appearance of metabolites were also observed.

Paralysis in herpes zoster

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Aldrin and dieldrin: loss under sterile conditions

After their application to sterile nutrient agar, both aldrin and dieldrin disappeared rather rapidly from the agar in glass-covered petri dishes. In most instances this disappearance was considerably retarded from agar inoculated with either fungi or bacteria. In the presence of microorganisms, aldrin was also epoxidized into dieldrin. Half of the applied aldrin volatilized from the agar during the first day of incubation; dieldrin volatilized more slowly and at a constant rate.

Analysis of three stimulation-seeking scales

3 measures of stimulation seeking were administered to 128 pre-freshman students and 97 general psychology students. Normative data were provided and compared with previous data. Significantly higher means and correlations among scales were obtained for the general psychology students than for the pre-freshman students. It is possible that the Sensation-seeking Scale (SSS) tends to measure more variable characteristics than SVS or CSI. However, it is equally possible that these differences may be due to lack of reliability of the SSS or the insensitivity of the other two to change. Which of the possibilities may be or is the case is not evident from these data.

Toxic epidermal necrolysis: the scalded skin syndrome

Toxic epidermal necrolysis is a condition that may occur in all age groups and resembles skin scalding. It presents as a generalized, markedly tender erythema and rapidly progresses to bullous desquamation of the superficial epidermal layers and systemic toxicity.The condition was first described in 1956. A review of the recent literature suggests that the incidence of the syndrome is increasing or it is being recognized more frequently. Its etiology has not been established, but it may represent unusual hypersensitivity to drug, bacterial, viral or immunization factors. The mortality rate in reported cases is approximately 30% and young children and debilitated adults are at greatest risk.Recently, two children with this condition were successfully treated at the Montreal Children's Hospital, using protective isolation, intensive nursing care, intravenous antibiotics and hydrocortisone hemisuccinate. Early use of corticosteroids may inhibit the progression of epidermal necrolysis and improve the prognosis.