Investigations into the survival of Mycoplasma gallisepticum, Mycoplasma synoviae and Mycoplasma iowae on materials found in the poultry house environment

Following preliminary experiments to determine suitable methods for studying mycoplasma survival, suspensions of Mycoplasma gallisepticum (four strains), Mycoplasma synoviae (two strains) or Mycoplasma iowae (two strains) were seeded onto replicate samples of cotton, rubber, straw, shavings, timber, food, feathers and human hair. The organisms were also seeded onto human skin, ear and nasal mucosa. All samples were cultured for viability after 4, 8, 12 and 24 h, and then daily up to 6 days. The identity of recovered mycoplasmas was confirmed by indirect immunofluorescence. All three Mycoplasma species survived for the longest time on feathers with M. gallisepticum surviving between 2 and 4 days and M. synoviae 2 to 3 days. The type strain of M. iowae remained viable for 5 days on feathers, while the field strain was still viable at the end of the 6-day experiment. This strain also survived for at least 6 days on human hair and several other materials. M. gallisepticum survived on human hair up to 3 days and one recent field isolate also survived in the nose for 24 h. Survival times of the organisms were generally less on other materials although M. gallisepticum could be isolated from straw, cotton and rubber samples after 2 days.     

Pitfalls in the interpretation of leukocyte counts of newborn infants.

Some pitfalls in the interpretation of neonatal leukocyte counts are identified. The well-known variability in neonatal leukocyte counts was investigated by simultaneously sampling arterial, venous and capillary blood, and during periods of rest and mild and violent exercise. Venous blood leukocyte counts were 82% +/- 3.5 (mean +/- SE, P = less than .001) of counts in simultaneously drawn capillary blood from heel punctures; arterial blood counts were 77% +/- 5.3 (P less than .001) of capillary blood values. Following violent crying, capillary blood leukocyte counts increased to 146% +/- 6.1 (P less than .001) of baseline values, and a shift to the left occurred. Milder exercise induced an increase to 113% +/- 5.2 (P less than .05), without a leftward shift. Thus, counts from different vascular sources cannot be considered equivalent. Also, counts from vigorously crying babies may show leukocytosis and a leftward shift, and erroneously suggest bacterial infection. It is recommended that serial counts be obtained from a consistent vascular source in resting babies.     

DNA-aneuploidy in 46,XX hydatidiform moles

The DNA content of single villous cell nuclei in 14 normal pregnancies and 21 androgenetic moles with a 46,XX karyotype was measured by flow cytometry. Six molar specimens showed a low mean DNA content close to that of normal villi, whereas, 15 specimens were characterized by a high mean DNA content due to a large fraction of nuclei in the triploid to tetraploid region. The latter group presumably corresponds to the previously described "type II" moles in which the DNA pattern resembled the pattern seen in invasive moles and choriocarcinoma.     

The adaptation of the plaque reduction assay for measuring specific cytotoxic cells in limiting dilution cultures

The use of the original haemolytic plaque reduction technique to measure cytotoxic T lymphocytes (CTL) has been developed further as a rapid screening assay, particularly suitable for limiting dilution analyses. Using hybridoma cells as targets, the cytotoxicity has been measured by the loss of haemolytic plaque formation and by the reduction of the amount of haemolytic monoclonal antibody secreted from viable target cells into the assay supernatants. The assessment of large numbers of cytotoxic samples has been greatly facilitated by quantitating the amount of haemoglobin released in the assay with an automated microELISA multiscanner and by scoring visually using a modification of the spot test. Using these new techniques, relatively high frequency estimates of cytotoxic cell precursors in an allogeneic response (1 in 462 spleen cells) and an anti-fluorescein response (1 in 3970 spleen cells) were obtained.     

Taxonomy of 37-collar spined Echinostoma (Trematoda: Echinostomatidae) in studies on the population regulation in experimental rodent hosts

With reference to a recent taxonomic revision the species of the echinostomes used in key studies on the population regulation in infections with 37-collar-spined Echinostoma species in experimental rodent hosts were reconsidered. This was considered essential to prevent taxonomic problems blocking further fruitful progress within this field of experimental parasitology.     

Age-related changes of exercise-induced plasma catecholamines and neuropeptide Y responses in normal human subjects.

Age-related plasma noradrenaline and neuropeptide Y were evaluated in seven young (mean +/- SD, 28 +/- 3 years) and seven elderly (64 +/- 8 years) normal subjects during rest and different work loads on a cycle ergometer. In the supine and the sitting position plasma noradrenaline and neuropeptide Y were almost identical in the two groups. Plasma neuropeptide Y did not increase during exercise at 100 W for 15 min. At this load plasma noradrenaline levels were higher in the older subjects (mean +/- SEM, 0.97 +/- 0.12 vs. 0.60 +/- 0.09 ng ml-1). There was a significant correlation between plasma noradrenaline and the relative work load at 100 W (r = 0.794, P = 0.0007). At 75% of maximal work load plasma noradrenaline and neuropeptide Y were higher in the young group (1.84 +/- 0.16 vs. 1.26 +/- 0.13 ng ml-1 (noradrenaline) and 38 +/- 4 vs. 22 +/- 5 pmol l-1 (neuropeptide Y)). In the elderly group plasma neuropeptide Y did not increase during exercise and showed a tendency to fall below basal level 5 min post-exercise. It is concluded, that plasma noradrenaline does not increase more in older subjects during exercise when correcting for the generally lower physical fitness in this group compared to younger subjects, and that plasma neuropeptide Y does not increase during exercise in older subjects, suggesting an age-reduced capacity in this system.     

Bioavailability of oestradiol and oestriol administered orally to oophorectomized women

A bioavailability study was performed on ten oophorectomized women in a randomized cross-over design. The absorption of tablets containing 2 mg of micronized oestradiol and 1 mg of micronized oestriol (Estrofem®) was compared to the absorption of the same micronized hormones administered in an aqueous suspension. Serum concentration values of oestradiol, oestriol and oestrone were measured by radioimmunoassay. The data obtained were analyzed both by univariate and multivariate analyses, and neither the serum concentrations at the various sample times, the maximum concentrations, the times for the maximum concentrations, nor the areas under the serum concentration curves disclosed any significant differences between the tablet and suspension administrations at the 5% level. The serum concentration values achieved by giving 2 mg of oestradiol and 1 mg of oestriol were of the same magnitude or higher than those of the normal menstrual cycle.