Method of sampling chorionic villi in first trimester of pregnancy under guidance of real time ultrasound.

Samples of chorionic villi were obtained in the first trimester by aspiration using a cannula passed transcervically under the guidance of real time ultrasound. In initial studies in 47 anaesthetised patients immediately before therapeutic abortion a method was developed giving a success rate of 89%. In 10 patients successful sampling was performed as an outpatient procedure without anaesthesia. In all, seven diagnostic procedures were undertaken and four of the five unaffected pregnancies continued. The technique of chorionic villous sampling using real time ultrasound is simple to learn and yields material for biochemical analysis and chromosomal study without the need for tissue culture. The exact obstetric risk, however, remains to be defined.     

Collagen receptors mediate early events in the attachment of epithelial (MDCK) cells

Summary Madin-Darby canine kidney (MDCK) cells kept in suspension culture for 12–15 hr displayed high-affinity binding sites for¹²⁵I-lathyritic (soluble) collagen (120,000/cell,K _D =30nm) and preferred collagens types I and IV over laminin or fibronectin as substrates during the first hour of attachment. On the other hand, after 4 hr, attachment to all four substrates was equally efficient. Upon challenge with a collagen substrate, the high-affinity sites were rapidly recruited on it (T1/2=6 min). Their occupancy by soluble collagen triggered the exocytosis of a second large population of low-affinity collagen binding sites that included laminin and seems to be involved in a second cell-attachment mechanism. These results are compatible with a twostep model of MDCK cell attachment to the substrate: first, via high-affinity collagen binding sites, and second, via laminin of cellular origin.     

Routine smoking cessation intervention in health care systems.

Everyone agrees that insurance for long-term care is inadequate in the United States. Disagreement exists, however, on whether such insurance should be provided through the private or public sector. Private insurance generally uses the experience-rating principle that persons with higher risk of illness are charged higher premiums. For private insurance for long-term care, this principle creates a dilemma. Most policies will be purchased by the elderly; yet, because the elderly have a high risk of needing long-term care, only about 20% of them can afford the cost of premiums. A public-private partnership by which the government partially subsidizes private long-term-care insurance is unlikely to resolve this dilemma. Only a social insurance program for long-term care can provide universal, affordable, and equitable coverage.     

Avian hepatic T3 generation by 5'-monodeiodination: characterization of two enzymatic pathways and the effects of goitrogens

The enzymatic nature of 5'-monodeiodination (5'-D) in avian liver homogenates was demonstrated by abolishment of activity by iopanoic acid (IOP). T3 production from T4 was dependent on enzyme and substrate concentrations, incubation time, incubation temperature, and pH. Two pathways of 5'-D activity were present in avian liver and exhibited characteristics similar to those described in mammalian tissues. Type II activity was identified as propylthiouracil (PTU)-insensitive activity. Type I (PTU-sensitive) was determined by difference between Total and Type II. Km values were 1.58 microM T4 for Total activity and 0.90 nM T4 for Type II, corresponding to the characteristics of the mammalian pathways. The effects of goitrogens on avian hepatic 5'-D were equivalent to those reported for the mammalian enzyme.     

Parathyrin and calcitonin stimulate cyclic AMP accumulation in cultured murine brain cells.

Despite the key role Ca2+ plays in the nervous system, biochemical actions on neural tissue of the Ca2+-regulating peptide hormones parathyrin and calcitonin were unknown. Until a few years ago only neurons, but not glial cells, were considered as targets for peptide hormones. Our recent observation that peptide hormones do indeed act on glial cells is extended by the present report that these cells respond to the calcaemic peptide hormones parathyrin and calcitonin. In cultured murine brain cells mainly consisting of glioblasts, parathyrin stimulates the accumulation of cyclic AMP. The half-maximal effect is elicited at 30 nM parathyrin. With rat brain cells the effects are three times those observed with mouse brain cells. Calcitonin, which is less potent than parathyrin, elevates the concentration of cyclic AMP only in rat brain cells. If properly occupied, the inhibitory receptors present on the cells lower the increase in the level of cyclic AMP evoked by parathyrin and, to some extent, that elicited by calcitonin. The results suggest that: (i) these or closely related hormones might exert regulatory functions in brain; and (ii) glial cells must be considered in discussions of the targets of the calcaemic and other peptide hormones.     

Flavonoids of Sullivantia: Taxonomic implications at the generic level within the saxifraginae

Sullivantia species were found to produce quercetin 3-O-glycosides, several of which contain glucuronic acid, as well as pedalitin (6-hydroxy-7-O-methyl luteolin), pedalitin 6-O-glycosides, and small amounts of luteolin. Sullivantia has a unique combination of compounds that distinguishes it from other genera in the Saxifraginae for which flavonoid data are available. The nature of the flavonoid compounds is in accordance with a general trend within the Saxifragaceae of reduction and replacement of flavonols by flavones.