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Notes: Objectives To determine whether the change in erythrocyte potassium content in normal human pregnancy is accompanied by a similar change in erythrocyte chloride content. To assess erythrocyte hydration and potassium and chloride content in pregnancies complicated by proteinuric pregnancy induced hypertension.Design A serial study during and after normal pregnancy. A comparative study during and after pregnancies complicated by proteinuric pregnancy induced hypertension (PIH). Erythrocyte hydration, total osmoles, potassium and chloride and plasma osmolality were determined.Setting University teaching hospital, UK.Subjects Twenty-eight women studied at 14, 28 and 36 weeks of normal pregnancy and ten women with PIH studied during the third trimester of pregnancy. All women were reinvestigated 20 weeks after delivery.Results The fall of erythrocyte potassium early in normal pregnancy (277.4 vs 265.2 mmol/kg; P〈0.02) and its rise between 28 and 36 weeks (272.3 vs 288.0 mmol/kg; P〈0.005) were accompanied by similar changes in erythrocyte chloride content (151.9 vs 131.1 mmol/kg; P〈0.001 and 129.4 vs 141.3 mmol/kg; P〈0.001, respectively). Plasma osmolality in PIH was raised above that normal in pregnancy (287.2 vs 283.0 mosm/kg; P〈0.005). In PIH, compared to normal pregnancy, erythrocyte hydration (2.00 vs 1.89 l/kg dry weight cells), total osmoles (573.0 vs 534.2 mosm/kg), potassium (303.0 vs 288.0 mmol/kg) and chloride (154.9 vs 141.3 mmol/kg) were greater.Conclusions These findings further support the hypothesis that changes in plasma osmolality in pregnancy are secondary to alterations in cell osmoles and serve to limit changes in cell hydration. Erythrocyte composition and plasma osmolality are altered in PIH.

Notes: Abstract: Metabolism of [U-13C5]glutamine was studied in primary cultures of cerebral cortical astrocytes in the presence or absence of extracellular glutamate. Perchloric acid extracts of the cells as well as redissolved lyophilized media were subjected to nuclear magnetic resonance and mass spectrometry to identify 13C-labeled metabolites. Label from glutamine was found in glutamate and to a lesser extent in lactate and alanine. In the presence of unlabeled glutamate, label was also observed in aspartate. It could be clearly demonstrated that some [U-13C5]glutamine is metabolized through the tricarboxylic acid cycle, although to a much smaller extent than previously shown for [U-13C5]glutamate. Lactate formation from tricarboxylic acid cycle intermediates has previously been demonstrated. It has, however, not been demonstrated that pyruvate, formed from glutamate or glutamine, may reenter the tricarboxylic acid cycle after conversion to acetyl-CoA. The present work demonstrates that this pathway is active, because [4,5-13C2]glutamate was observed in astrocytes incubated with [U-13C5]glutamine in the additional presence of unlabeled glutamate. Furthermore, using mass spectrometry, mono-labeled alanine, glutamate, and glutamine were detected. This isotopomer could be derived via the action of pyruvate carboxylase using 13CO2 produced within the mitochondria or from labeled intermediates that had stayed in the tricarboxylic acid cycle for more than one turn.

Notes: Suspensions (20%) of microfine and ACS grade zinc oxide, or 20% titanium oxide in water, castor oil or polyethylene glycol were applied topically to rabbit skin over 4 h (1 day) or 2 h daily (3 days). Skin sites were analysed for metal uptake. Percutaneous absorption of the oxides was probably low, most remaining on the skin surface. Uptake patterns were influenced by the vehicles used. Appreciably more microfine zinc oxide was taken up by the skin in subacute studies. Local changes in trace metal concentration were construed as evidence of percutaneous absorption of zinc and titanium oxides. Further studies are indicated to validate the significance of these preliminary observations. On a applique superficiellement a de la peau de lapin des suspensions a 20% d'oxyde de zinc de qualite microfine ou ACS, ou a 20% d'oxyde de titane dans l'eau, l'huile de castor ou le polyethylene glycol, durant 4 heures (1 jour) ou 2 heures par jour (3 jours). On a analyse l'absorption de metal par la peau. L'absorption transcutanee des oxydes est probablement faible, la majeure partie restant en surface. Le deroulement de l'absorption est influence par le vecteur utilise. On constate que notablement plus d'oxyde de zinc microfin est absorbe par la peau dans les etudes subaigues. Les modifications locales dans la concentration des traces de metal ont ete interpretees comme des preuves d'absorption transcutanee d'oxydes de zinc et de titane. Des etudes ulterieures sont necessaires pour valider la signification de ces observations preliminaires.

Notes: The effects of aqueous solutions of 2-hydroxyalkanoic acids and analogous materials on the extensibility of an in vitro model for human stratum corneum have been investigated. The increase in extensibility of stratum corneum caused by treatment with 2-hydroxy acid solutions reaches a peak at C8 in the case of the saturated molecules. Introducing unsaturation into the hydrocarbon chain shifts the point of maximum efficacy to a longer chain length. Further modifications to the molecular backbone, such as the replacement of a methylene group by heteroatoms, can improve significantly the relative plasticization obtained from aqueous treatment. Alteration of the acidic head group markedly influences the elasticity increase. The free acid is the most efficacious species. An increase in the pKa of HCA by the addition of polyol increases the extensibility improvement. Movement of the hydroxyl group from C-2 is not advantageous, but replacement with a 2-thio derivative is beneficial in terms of increased plasticization. The best systems for improving extensibility have a strong affinity for protein.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméNous avons analysé les effets de solutions aqueuses d'acides 2-hydroxyalkanoïques et de matériaux similaires sur l'extensibilité in vitro d'un échantillon de stratum corneum humain. L'augmentation de l'extensibilité du stratum corneum générée par le traitement aux solutions des acides 2-hydroxy atteint un pic à C8 dans le cas de molécules saturées. L'introduction d'une insaturation au niveau de la chaîne d'hydrocarbone amène le point d'efficacité maximum à une chaîne plus longue. Des modifications apportées aux molécules principales, telles que le remplacement du groupe méthylène par des hétéroatomes peuvent améliorer de façon significative la plasticité relative obtenue par un traitement aqueux. L'altération du groupe acide de tête influence de façon notable l'augmentation de l'élasticité. L'acide libre est la plus efficace. Une augmentation du pKa de l'acide 2-hydroxy caprylique par addition de polyol accroît l'amélioration de l'extensibilité. Le deplacement du groupe hydroxy de C-2 n'est pas efficace mais le remplacement par des dérivés 2-thio améliore la plasticité. Les systémes qui améliorent au maximum l'extensibilité ont une affinité importante avec les protéines.

Notes: Serial measurements of serum progesterone, oestradiol, human chorionic gonadotrophin (hCG) and human placental lactogen (hPL) have been determined in 33 women experiencing early pregnancy failure and compared with the values of the same hormones in 72 healthy women having uncomplicated pregnancies. Steroid production by the corpus luteum seemed similar in both groups up to 6 weeks gestation but thereafter placental steroidogenesis was not evident in those women in whom spontaneous pregnancy losses occurred. Placental production of the two protein hormones, hCG and hPL, did take place, and whereas the circulating levels were not as high as in normal pregnancies, levels did usually increase before clinical evidence of miscarriage occurred. hCG was not a sensitive discriminator of subsequent failure. In these women there were no significant hormone differences between those with evidence of a fetus and those without.

Notes: Summary. In a double blind trial, 60 nulliparae with a modified Bishop score of 〈inlineGraphic alt="leqslant R: less-than-or-eq, slant" extraInfo="nonStandardEntity" href="urn:x-wiley:14700328:BJO827:les" location="les.gif"/〉5 requiring induction of labour, received either 8 mg of salbutamol or an identical placebo orally, 30 min before vaginal administration of 2 mg prostaglandin E2 gel. Women in the salbutamol group experienced less uterine activity over the subsequent 12 h compared with those given placebo, and fewer (35%) commenced labour compared with the placebo group (62%). However, the change in cervical score was significantly less in the salbutamol group (mean 3.0, SD 3.1) than that in the placebo group (mean 5.8, SD 3.2), and the prostaglandin treatment to delivery time in the salbutamol group (mean 26.1 h, SD 6.49) was significantly longer than that in the placebo group (mean 19.3 h, SD 7.95). The first stage of labour lasted 〉10h in 11 women in the salbutamol group compared with five in the placebo group. Side effects attributable to salbutamol occurred in 10% 〉 of the treated women but in none of their fetuses and fetal outcome was satisfactory and similar in both groups. Our findings show that salbutamol can suppress prostaglandin-induced uterine activity during cervical ripening, which could be an advantage in induction of labour where a planned delivery is preferred. However, the poorer outcome of labour in salbutamol-treated women mitigates against this approach.

Notes: Forty patients have been studied over 96 menstrual cycles during which a blood sample was obtained within five days of the next menstrual period. Two features emerged: circulating concentrations of progesterone and oestradiol could be elevated on the day bleeding began and conversely the levels of these hormones could be low for some days without menstruation occurring. These data suggest there may not be any direct relation between circulating ovarian hormone levels and the onset of menstrual bleeding.

Notes: The fetal heart rate was monitored during 30 deliveries by Caesarean section. General anaesthesia, but not epidural analgesia, caused a loss of beat-to-beat variation, but appeared to have no other adverse effects on fetal heart rate. The loss of beat-to-beat variation occurred after intravenous thiopentone and was most marked when atropine was used as premedication.

Notes: Summary. Serial measurements of serum progesterone, oestradiol, prolactin, human chorionic gonadotrophin (hCG) and human placental lactogen (hPL) have been determined in 32 healthy women at regular intervals throughout pregnancy. The data confirm previous reports that levels of these hormones vary widely between individuals at each stage of gestation, but further analyses have shown two other features: first there is a clear tendency for individuals to retain their rank in the spectrum of hormone values throughout pregnancy; second when the concentrations of the individual hormones (except hCG) are transformed to logarithmic values, the trends within individuals approximate well to straight lines during the second and third trimester of pregnancy. These findings provide a relatively simple method for describing the rates of change in the concentrations of these hormones and for examining possible relations between them. They also suggest that the quality of the maternal endocrine milieu may be determined at an early stage of gestation.