Increase in urinary thromboxane excretion during pregnancy and labor

Urinary TXB₂ excretion was measured during pregnancy and labor using high pressure liquid chromatography and radioimmunoassay. From the first trimester onwards TXB₂ levels in urine of pregnant women (n=60) were significantly (p <0.001) higher than in non-pregnant women (n=12) and they increased, albeit not significantly, with advancing gestation. Labor was associated with a two-fold increase in urinary TXB₂ excretion. Levels in established labor were significantly higher than at any other time in pregnancy (p <0.001), but the levels in incipient labor showed considerable overlap with these in late pregnancy. Thus urinary TXB₂, while not necessarily originating from the pregnant uterus, appears to reflect the uterine activity of labor and may be the expression of a general stimulation of prostanoid production during parturition.     

The combined action of p-aminosalicylic acid and streptomycin with isonicotinic acid hydrazide in vitro

Summary A method is described of investigating and representing graphically the simultaneous action of two antibacterial agents. The results are reported of the investigation with the H₃₇R_v strain and the PAS and INH resistant forms obtained from this strain on mixtures of PAS and INH, and the results of the investigation with the H₃₇R_v strain and the streptomycin and INH resistant forms obtained on mixtures of streptomycin and INH. It appears that there is a definite synergism in mixtures containing about 99% PAS and 1% INH. Additivity, to slight antagonism, is found in mixtures consisting of streoptomycin and INH. This research was supported in part by Riker Laboratories Inc., Los Angelos, California.     

The physiology and ecology of a novel, obligate mycophagous flagellate

Abstract To determine if conidia of the nematophagous fungus Drechmeria coniospora are subject to predation by soil protozoa, several sandy soils were enriched with 10⁹ conidia of this fungus per g dry soil. After incubation of the samples at 20°C for three weeks, a flagellate was detected as the most dominant mycophagous protozoan. Conidia of several fungi, with minimum diameters between 2 and 16 μm, supported growth of this flagellate, irrespective of pigmentation. Bacteria however could not be used for growth, although bacteria and also latex beads of the same size were ingested. This is, to our knowledge, the first report of an obligate mycophagous soil-borne flagellate. The flagellate was able to grow at the expense of the conidia of D. coniospora in liquid culture, with a specific growth rate of about 0.1 h⁻¹; the optimum temperature was 20–24°C. Approximately 10 D. coniospora conidia were required for one flagellate division. In sterilized soil, enriched with 10⁸ D. coniospora conidia per g dry soil, the specific growth rate was 0.014 h⁻¹, when the soil was at 50 or 65% of its water-holding capacity (WHC). In drier soil, i.e. 25% WHC, no growth took place. During growth of the flagellate in soil, the number of D. coniospora was reduced by about 20%, which was in the same order of magnitude as expected on the basis of the requirement of 10 D. coniospora conidia for one flagellate division. Since many conidia remained in the soil after growth of the flagellate, we concluded that although the flagellate is an interesting organism, it does not play a very important role in the survival of D. coniospora conidia in the soil.