Carrier screening for cystic fibrosis

A number of different models of CF carrier screening have now been tested in pilot trials. Apart from opportunistic and cascade testing (which are strictly speaking not true forms of screening), the major programmes have been directed either to young adults in primary care or to pregnant women in antenatal clinics. Only in the latter form of screening has sufficient data been collected to allow conclusions to be reached on the optimum mode of delivery. It seems very probable that when CF carrier screening passes into routine service, it will be the antenatal couple model that is used.     

Neonatal lung function following mid-trimester amniocentesis

Three hundred and fifty-four women who underwent midtrimester genetic amniocentesis were matched for age, parity, indication, and smoking history, with an equivalent number of women who had declined the procedure, for the purpose of comparing the neonatal respiratory status of their offspring. There was no evidence that the infants exposed to genetic amniocentesis were compromised.     

Prenatal diagnosis of gastrointestinal obstruction: A correlation between prenatal ultrasonic findings and postnatal operative findings

The impact of prenatal sonographic diagnosis of oesophageal and gastrointestinal obstructions has been analysed over a 10-year period. Three groups of patients were evaluated. The first group consisted of 46 newborns with abnormal prenatal sonogratns, 41 of which were confirmed to have intestinal obstruction postnatally. The second group consisted of 17 neonates with normal prenatal sonograms who had intestinal obstruction postnatally. The third group included 56 newborns who did not undergo a prenatal sonogram but who had intestinal obstruction confirmed at surgery. Polyhydramnios without the appearance of a stomach on ultrasound was diagnostic of pure oesophageal atresia. Polyhydramnios with intestinal dilation was diagnostic of intestinal obstruction. Although surgery was performed earlier in the infants diagnosed prenatally with ultrasound, mortality was no less than in the group that did not undergo a prenatal sonogram, probably because of the high incidence of associated anomalies.     

Serum alpha-fetoprotein and neural tube defects in the first trimester of pregnancy

As part of the Medical Research Council randomized trial of vitamin supplementation in the prevention of neural tube defects (NTDs), maternal serum alpha-fetoprotein (AFP) was available for 19 NTD pregnancies. Each of these was matched with four unaffected controls, by maternal age, participating centre, and duration of sample storage. The samples came from women whose gestational age ranged from 6 to 14 completed weeks. The median AFP level in the affected pregnancies was 1·2 multiples of the median value in unaffected pregnancies of the same gestational age (95 per cent confidence interval (CI) 0·83–1·59). This confirmed the view that serum AFP measurement is of no practical value in the detection of NTDs in the first trimester of pregnancy. The study also showed that folic acid supplementation, used as a method of preventing NTDs, had no effect on the concentrations of maternal serum AFP up to 14 weeks of pregnancy.     

Manganese-oxidizing fungi and bacteria

The Science of Nature -     

Environmental principles applicable to supply chains design and operation

In this paper we deal with the problem of identifying environmental principles for the design and operation of supply chains. The operations that are included in supply chains are briefly described along with the approaches that are applied in order to improve their environmental performance. A background of environmental principles for achieving eco-efficiency and building of environmentally friendly organizational systems is presented and emphasis is put on the application of such principles “from cradle to grave”. Then, environmental principles applicable to particular objects of logistics networks planning are identified and commented upon. In addition, selective case studies from the literature, which show the applicability of the formulated principles and their relevance to practice, are discussed. The paper concludes with some remarks regarding the benefits for companies and societies, in general, that occur as a result of the application of the formulated principles.