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Notes: We present an experimental study of velocity statistics for a partial layer of inelastic colliding beads driven by a vertically oscillating boundary. Over a wide range of parameters (accelerations 3–8 times the gravitational acceleration), the probability distribution P(v) deviates measurably from a Gaussian for the two horizontal velocity components. It can be described by P(v)∼exp(−|v/vc|1.5), in agreement with a recent theory. The characteristic velocity vc is proportional to the peak velocity of the boundary. The granular temperature, defined as the mean square particle velocity, varies with particle density and exhibits a maximum at intermediate densities. On the other hand, for free cooling in the absence of excitation, we find an exponential velocity distribution. Finally, we examine the sharing of energy between particles of different mass. The more massive particles are found to have greater kinetic energy. © 1999 American Institute of Physics.

Notes: Transforming growth factor-β2 promotes healing in a variety of animal models and exhibits clinical effects thought to be mediated by connective tissue formation. Two clinical trials were conducted to evaluate the safety and effect of transforming growth factor-β2 purified from bovine bone and delivered topically to venous stasis ulcers three times per week for up to 6 weeks by means of a lyophilized collagen vehicle. The first was an open-label trial comparing transforming growth factor-β2 purified from bovine bone (0.5 µg/cm2) with a placebo consisting of lyophilized collagen vehicle-without active drug. After no safety issues arose in that trial, a prospectively randomized, closed-label, observer-blinded, three-armed trial was conducted to compare bovine transforming growth factor-β2 (2.5 µg/cm2) with the collagen matrix placebo vehicle and with a standard dressing. Standardized elastic compression was applied to all test extremities. The rate of reduction of ulcer area as measured by planimetry was the primary measure of effect. No serious safety-related events occurred in either trial. Clinical evaluation suggested that improvement in the quality and quantity of granulation tissue appeared to precede epithelialization of ulcers treated with bovine transforming growth factor-β2. In both studies, treatment with bovine transforming growth factor-β2 appeared to have a positive effect on the rate of ulcer closure, whereas ulcers in the control groups continued to exhibit impaired healing. In the open-label study, the mean rate of closure of ulcers treated with bovine transforming growth factor-β2 was significantly greater than that of ulcers treated with placebo. There was likewise enhanced reduction in ulcer area in the ulcers treated with bovine transforming growth factor-β2 in the second trial. However, because of a higher variability in patient response and a greater placebo effect, the difference was not significant. The placebo was not worse than the standard care arm, thereby showing that the vehicle is not injurious to healing. The combined results of the two trials suggest that, at doses of 0.5 to 2.5 µg/cm2, bovine transforming growth factor-β2 is safe as a topically applied agent in a collagen matrix vehicle and can have a positive effect on closure of venous stasis ulcers. Large multicenter trials appear to be indicated to evaluate fully the potential utility of transforming growth factor-β2 in accelerating closure of chronic dermal ulcers.

Notes: Objective To investigate a HLA-G deletion polymorphism in pre-eclamptic pedigrees and the general population.Design A population association study of HLA-G genotypes from pre-eclamptic/eclamptic patients and control groups.Setting Analyses undertaken in the School of Biological Sciences, Macquarie University. Patients were from Royal Women's Hospital, Melbourne, and controls were from Westmead Hospital and Macquarie University, Sydney.Subjects One hundred and ninety-six individuals, consisting of 29 pre-eclamptic/eclamptic (PE/E) patients, 13 individuals born of a PE/E pregnancy, 46 blood relatives of PE/E patients, 21 husbands of PE/E patients, 25 women normotensive in first pregnancy, 15 husbands of women normotensive in first pregnancy and 47 staff and students of Macquarie University.Results Genotypic and gene frequencies were not significantly different in the seven groups examined.Conclusion There is no detectable relationship between susceptibility to pre-eclampsia or being born of a pre-eclamptic pregnancy and HLA-G genotype.

Notes: Summary. From a study of 2000 consecutive labours the outcome of the 684 primigravid patients admitted in spontaneous labour has been examined according to their cervimetric progress during the first stage of labour. A partogram and labour stencil were used to identify dysfunctional labour which was treated with a standard protocol of augmentation by oxytocin. This policy achieved labours with a mean‘observed first stage’ of 6.3 h and a caesarean section rate of 8.7%. There was one stillbirth due to multiple congenital abnormalities and no increase in perinatal morbidity. Our data show that the type of first stage cervimetric pattern is helpful in predicting the outcome of labour. A normal cervimetric pattern resulted in a vaginal delivery rate of 98.4%; primary dysfunctional labour, which could be improved by oxytocin, had a 93.8% incidence of vaginal delivery, but if there was no improvement in the rate of cervical dilatation when this was administered the vaginal delivery rate was only 22.7%. A prolonged latent phase was associated with a caesarean section rate of 16.7% and the incidence of neonatal intubation was nearly as high as that found in uncorrected primary dysfunctional labour. The neonatal asphyxia in secondary arrest was minimal with an overall caesarean section rate of 28.4%; there was no increased incidence of neonatal morbidity with this cervimetric type.

Notes: In order to distinguish between a maternal, fetal or maternal and fetal genetic predisposition towards severe pre-eclampsia, the first pregnancies of 158 mothers and 160 mothers-in-law of pre-eclamptic women and of matched controls were analysed. Fourteen per cent of mothers of pre-eclamptics were found to have had severe pre-eclampsia, confirming previous suggestions that the condition‘runs in families', in contrast to only a 3% incidence amongst mothers of controls. The incidence in mothers-in-law of both pre-eclamptics and controls was 4%, in full agreement with a maternal genotype hypothesis and suggesting that the fetal genotype plays, at most, only a minor role in the aetiology of severe pre-eclampsia. The data are in agreement with the hypothesis that a single recessive gene acting in the mother could be responsible for severe pre-eclampsia, but multifactorial inheritance is not ruled out. Mild pre-eclampsia showed no such familial tendency, indicating that the mild and severe forms of pre-eclampsia may represent separate pathological entities.

Notes: Abstract: Peptide aldehyde inhibitors of the chymotrypsin-like activity of the proteasome (CLIP) such as N-acetyl-Leu-Leu-Nle-H (or ALLN) have been shown previously to inhibit the secretion of β-amyloid peptide (Aβ) from cells. To evaluate more fully the role of the proteasome in this process, we have tested the effects on Aβ formation of a much wider range of peptide-based inhibitors of CLIP than published previously. The inhibitors tested included several peptide boronates, some of which proved to be the most potent peptide-based inhibitors of β-amyloid production reported so far. We found that the ability of the peptide aldehyde and boronate inhibitors to suppress Aβ formation from cells correlated extremely well with their potency as CLIP inhibitors. Thus, we conclude that the proteasome may be involved either directly or indirectly in Aβ formation.

Notes: Summary. A prospective controlled study of 2000 patients to determine the incidence of postmaturity and the effect of a policy of non-induction of labour in prolonged pregnancy is reported.‘Certain postmaturity’ was identified in 4% of the patients and was associated with an increased incidence of babies with Apgar scores of 〈5 at 1 min; induction of labour at 42 weeks gestation did not affect the neonatal outcome compared with that in patients allowed to go into spontaneous labour. Induction of labour in patients designated as‘certain postmature’ and‘uncertain postmature’ reduced the number of vaginal deliveries and increased the caesarean section rate from 9.6 to 26.7 and from 2.2 to 31.2% respectively. The failure to improve the perinatal outcome does not support or justify induction of labour for uncomplicated postmaturity.

Notes: The incidence of fetal breathing movements (FBM), fetal trunk movements (FTM), and total fetal activity (TFA) was assessed in 25 pregnancies complicated by maternal diabetes mellitus; 20 mothers had been juvenile insulin dependent diabetics, 4 were diagnosed during pregnancy (one of whom required insulin) and there was one other who was changed from chlorpropamide to insulin during the first trimester of pregnancy. Thirty-minute records were made postprandial between 32 and 38 weeks making a total of 161 recordings. There were 15 well-controlled insulin-dependent diabetic women with uncomplicated pregnancies; and in this group the mean percentage incidence of FBM was 60±25 (SD) per cent, FTM 16±10 (SD) per cent and TFA 73±22 (SD) per cent. The mean breathing rate per minute was 53±12 and the mean number of movements per 30-minute period 29±18. The incidences of FBM and TFA were significantly higher than those found in postprandial recordings in normal pregnancies. There was only one recording out of 115 where the incidence of TFA fell below 10 per cent. The mean percentage incidences of FBM, FTM and TFA were similar in the four uncomplicated pregnancies in which diabetes was diagnosed during pregnancy. The mean percentage incidence of TFA was significantly lower in the six pregnancies with obstetric complications, and levels of TFA below 10 per cent correlated well with abnormal cardiotocograph traces or fetal distress in labour.

Notes: Summary. From a study of 2000 consecutive labours, the outcome of 847 multigravid patients admitted in spontaneous labour was examined. Labour was classified according to the cervimetric pattern, and response to oxytocin given according to a strict protocol with the use of a nomogram and partogram. The mean ‘observed first stage’ was 3·4 h, and the caesarean section rate 1·4%. Normal labour occurred in 88·5%, with a vaginal delivery rate of 99·5% in this group. Stimulation was indicated in 98 patients (11·6%), augmentation improving the rate of progress in 86 (87·8%) of these, with vaginal delivery occurring in all but one. Successful accelerated labour was not associated with any increase in neonatal morbidity as judged by Apgar scores, intubation or transfer to the special care baby unit. Twelve patients did not have improvement following augmentation and seven were delivered by caesarean section, including one following a potentially preventable uterine rupture. The greatest neonatal morbidity was in the group with primary dysfunctional labour that did not improve with augmentation. It may be that this was related to the mode of delivery rather than augmentation, as there was no significant difference in neonatal condition between normal and abnormal labour if vaginal delivery occurred.