w e have shown previously (Couvreur et a1 1977) that polyacrylamide nanocapsules are a new type of lysosomotropic carrier, but unfortunately they are unlikely to be digested by lysosomal enzymes. This article describes the preparation and the morphology of polyalkylcyanoacrylate nanocapsules since polyaanoacrylate may be biodegradable, as suggested by its us in surgery (Collins et al 1969;Heisterkamp et al 1969) and by its chemical properties (Cameron et al 1965; Leonard et a1 1966 a, b; Pani et al 1968).We also present results of the sorption of small molecules on these nanocapsules.f Correspondence. b. 1. Morphological appearance of polymethyl-VUoacrylate nanocapsules by scanning electron -0scopy.Polymethyl and polyethylcyanoacrylate nanocapsules were prepared by polymerization. To Tween 20 (0.25 g), HCI 0.1 M (5.0 ml) in distilled water (50.0 ml) was added 0.6 ml of either of the monomers (methyl-or-ethylcyanoacrylate). After mechanically stirring for 30 min the mixture was passed through a fritted glass filter (pore size 9-15 pm) and then distilled water added t o 200 ml. After preparation, nanocapsules form milky suspensions displaying a Tyndall effect. The particles pass through a Millipore filter with 0.45 pm pores. This method is rapid and easy and avoids the destructive y-irradiation used in the preparation of polyacrylamide nanocapsules (Couvreur et al 1977).Scanning electron microscopy shows spherical particles with a diameter of about 200nm (Fig. 1). Variation of the Tween 20 concentrations did not affect the morphological appearance and size. Particles obtained without surfactant seem to be more agglomerated and larger than those with surfactant.Suspension of nanocapsules prepared with Tween 20 (0.1%) were spray frozen (Bachmann & SchmittFumian 1973) and examined by the electron microscope after freeze fracture. The use of fixatives and cryoprotectants are avoided by this method, while surfactants do not appreciably interfere. Fig. 2 shows that the inner structure appears to be highly porous, de-FIG. 2. The appearance of the internal structure of polymethylcyanoacrylate nanocapsules by the electron microscopy after spray freezing and cryofracture (see (Bachmann et al 1973) for details).

IntroductionBirthweight is used as an indicator of intrauterine growth, and determinants of birthweight are widely studied. Less is known about determinants of deviating patterns of growth in utero. We aimed to study the effects of maternal characteristics on both birthweight and fetal growth in third trimester and introduce placental weight as a possible determinant of both birthweight and fetal growth in third trimester.MethodsThe STORK study is a prospective cohort study including 1031 healthy pregnant women of Scandinavian heritage with singleton pregnancies. Maternal determinants (age, parity, body mass index (BMI), gestational weight gain and fasting plasma glucose) of birthweight and fetal growth estimated by biometric ultrasound measures were explored by linear regression models. Two models were fitted, one with only maternal characteristics and one which included placental weight.ResultsPlacental weight was a significant determinant of birthweight. Parity, BMI, weight gain and fasting glucose remained significant when adjusted for placental weight. Introducing placental weight as a covariate reduced the effect estimate of the other variables in the model by 62% for BMI, 40% for weight gain, 33% for glucose and 22% for parity. Determinants of fetal growth were parity, BMI and weight gain, but not fasting glucose. Placental weight was significant as an independent variable. Parity, BMI and weight gain remained significant when adjusted for placental weight. Introducing placental weight reduced the effect of BMI on fetal growth by 23%, weight gain by 14% and parity by 17%.ConclusionIn conclusion, we find that placental weight is an important determinant of both birthweight and fetal growth. Our findings indicate that placental weight markedly modifies the effect of maternal determinants of both birthweight and fetal growth. The differential effect of third trimester glucose on birthweight and growth parameters illustrates that birthweight and fetal growth are not identical entities.

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In the nonpregnant population, there is extensive evidence of a systemic low-grade inflammatory status in relation to excess adipose tissue. Less is known about the relation during pregnancy. Objective: Our main objective was therefore to explore the effect of pregnancy on adiposity-related systemic inflammation. Results: Maternal adiposity was associated with significantly higher circulatory levels of several inflammatory markers (CRP, MCP-1, IL-6, and IL-1Ra). However, this proinflammatory upregulation was not evident toward the end of pregnancy, as levels of CRP, MCP-1, and IL-6 were not any longer significantly different between the BMI categories. Conclusions: Although normal pregnancy exhibits proinflammatory features, this does not seem to have additive or synergistic effects on the inflammation associated with adiposity. On the contrary, we found that the BMI-dependent increase in proinflammatory markers was not evident at the end of pregnancy.

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