The influence on the pituitary-ovarian function,cervical mucus and vaginal cytology of a new progestational compound

A new progestational preparation, 17α-ethinyl-18-methyl-11-methylene-4-estren-17β-ol (Org 2969) was subjected to clinical and laboratory assessment. Five women, all with a previously regular bleeding pattern, received 60 μg daily for 21 days. The treatment entailed an appreciable change in pituitary-ovarian function. Thus, judging by daily determinations of FSH, LH, progesterone and oestrogen plasma concentrations, no volunteer ovulated. The characteristic mid-cycle FSH and LH peaks failed to appear, and progesterone was almost totally suppressed. Oestrogen showed, as during the control period, a mid-cycle peak, but it fell later, and 3 out of 5 volunteers had increased plasma levels. Changes in cervical mucus and vaginal cytology were observed. The quantity, appearance, and spinnbarkeit of the cervical mucus were approximately as in the luteal phase of the control period. No sperm penetration was observed $\text{in vitro}$. The karyopyknotic index did not reflect the increasing oestrogen values.     

Incorporation of [14C] nicotine into growing melanin

Foetal eye melanin in pigmented mice showed much greater accumulation of injected [N-methyl-¹⁴C] nicotine-d-bitartrate than maternal eye melanin (ratio ca. 5:1). Nicotine seems to be accepted as a precursor in the formation of new melanin, due possibly to a structural resemblance to the main precursor of melanin, indole-5,6-quinone.     

Increased absorption of polyethylene glycol 600 deposited in the colon in active ulcerative colitis.

A defect in the barrier function of the intestinal mucosa has been proposed as important in both the pathogenesis and systemic manifestations of inflammatory bowel disease. After colonoscopy, polymers of polyethylene glycol (PEG) with molecular weights of 414-810 (mean 600), were instilled in the descending colon of patients with ulcerative colitis (n = 17) and in controls without intestinal inflammation (n = 8). The patients with active ulcerative colitis (n = 6) had a significantly increased uptake of PEGs in the molecular weight range 458-810, measured as urinary excretion over the first 6 hours after instillation. The median values for their excretion were 2.85-3.80% of PEGs instilled compared with 0.32-0.94% for patients in remission (n = 11) (p < 0.05-0.01) and 0.17-0.60% for the controls (p < 0.05-0.01). The differences in absorption of PEG 414 did not reach the present level of statistical significance. There was a positive correlation between PEG absorption and the endoscopic and histological grading of inflammatory activity in the sigmoid colon (p < 0.01-0.001). These findings support a correlation between the presence of active inflammation and PEG absorption. There was little evidence to support the presence of a primary defect in the colonic barrier in patients with ulcerative colitis.     

Dynamic coil selection for real-time imaging in interventional MRI.

MR-guided intravascular interventions require image update rates of up to 10 images per second, which can be achieved using parallel imaging. However, parallel imaging requires many coil elements, which increases reconstruction times and thus compromises real-time image reconstruction. In this study a dynamic coil selection (DCS) algorithm is presented that selects a subset of receive coils to reduce image reconstruction times. The center-of-sensitivity coordinates and the relative signal intensities are determined for each coil in a prescan. During the intervention m coils are selected for reconstruction using a coil ranking based on the distance to the current slice or catheter position. In a phantom experiment for m = 6, an optimal signal-to-background ratio (SBR) was achieved and foldover artifacts were avoided. In three animal experiments involving catheter manipulation in the aorta and the right heart chamber, the anatomy was successfully visualized at frame rates of about 5 Hz using active catheter tracking.     

Toxicity of polymethylmethacrylate thermodegradation products

Polymethylmethacrylate was thermally degraded in air at 300° C and the volatile decomposition products studied with gas chromatography-mass spectrometry. The main product was monomeric methacrylate, although many other compounds existed among the products. Electron spin resonance spectroscopy revealed the presence of free radicals. Wistar rats were exposed to the fumes of the plastic (300° C) and their lungs and brain studied for biochemical effects. In the lung, the activity of 7-ethoxycoumarin O-deethylase decreased and an initial inhibition of glutathione peroxidase and superoxide dismutase was observed. The contents of reduced nonprotein sulfhydryl groups were decreased in the lung and brain. The exposures enhanced the activities of acetylcholine esterase, creatine kinase and NADPH-diaphorase in the brain. Scanning electron microscopy of the exposed lungs showed disorganization of ciliated cells, and the epithelial serous cells (Clara cells) were damaged.     

How does interferon exert its cell growth inhibitory effect?

Abstract: The interferons (IFNs) have become accepted therapy in a range of haematological and non-haematological malignancies. The mechanism behind IFN's antitumour action is, however, unclear. Interferons (IFNs) are capable of modulating a variety of cellular responses. One prominent effect of IFNs is their cell growth inhibitory activity, which has also been suggested to be of major importance in their antitumour action. In the present review we will discuss the cellular events leading to a decreased number of cells following IFN treatment, the molecular mechanisms underlying these phenomena, and the importance of these effects in a clinical perspective.