How many well-baby visits are necessary in the first 2 years of life?

Since we could find no scientific basis for the 10 well-baby visits recommended in the first 2 years of life in Ontario, we carried out a randomized trial in 570 healthy, low-risk newborns to determine the efficacy and safety of decreasing the number of scheduled well-baby visits from 10 to 5. Among the 466 babies still in the trial at the end of the study period those in the 10-visit group had had a mean of 7.63 scheduled and 0.26 unscheduled well-baby visits and those in the 5-visit group a mean of 4.77 scheduled and 1.42 unscheduled well-baby visits. Reducing the recommended number of visits did not result in an increased incidence of illness or an increased prevalence of undetected abnormality, and the physical development of the babies in the two groups was almost identical. The mean scores of the two groups in assessments of mental development, maternal-child relations, maternal anxiety and parental satisfaction with health care were close. The results suggest that the recommended number of well-baby visits for healthy, low-risk newborns can be reduced to five for children of multiparas and six for children of primiparas. Any additional well-baby visits should be scheduled according to the needs and experience of the parents.     

Saccharide distribution in human trophoblast demonstrated using fluorescein-labelled lectins

Synopsis The reactions of six Fluorescein-conjugated lectins with human trophoblast and foetal limb are described. The trophoblasi had marked membrane fluorescence affer treatment with wheatgerm andLotus tetragonolobus lectins. Concanavalin A reacted strongly with the trophoblastic cytoplasm but did not react with the nuclei. Most of the lectins had only weak reactions with foetal tissue, apart from the cartilage matrix which fluoresced strongly after treatment with several of the lectins. In addition, concanavalin A reacted with amylase-labile material, probably glycogen, in the skin epidermis and chondrocyte cytoplasm.Various substances were tested in order to determine the nature of the wheatgerm lectin receptor of trophoblast. Several secretory and binding proteins were found not to be responsible, and the identity of the receptor remains unknown.     

Solution properties of polygalacturonic acid

1. The specimen of polygalacturonic acid used in these studies was shown to contain very little neutral sugar, methyl ester groups or ash, and only residues of galacturonic acid. Its electrophoretic homogeneity was examined in pyridine–acetic acid buffer at pH6·5 and in borate buffer at pH9·2. The distribution of effective particle weights was shown to be fairly narrow. 2. The pH-titration curve of the polymer gave a pK value of 3·7. 3. The interaction of the polymer with Ruthenium Red was studied and titration curves were obtained for the spectral shifts associated with the formation of a complex. 4. Optical-rotatory-dispersion studies showed that the Drude constant, λ_c, was dependent on pH. 5. Polygalacturonic acid was shown to display non-Newtonian properties in solution and to have an anomalously high relative specific viscosity at low concentrations. 6. Studies were made of the pH-dependence of the sedimentation coefficient of the polymer. 7. These results are discussed in terms of the structure of the molecule and their relevance to the properties of pectic substances.