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Biomedical subjects

S L Barron

Publications and source records attributed to S L Barron.

At least 19 recordsLinked to original sources
PubMed1994

UVB levels.

Explore the source record for details and available documents.

Astronomy↗
PubMed1991

Use of monoclonal antibodies to enumerate spirochetes and identify Treponema denticola in dental plaque of children, adolescents and young adults.

Identification of spirochetes in dental plaque is difficult. Not all spirochetes can be cultured and microscopic analysis based on darkfield or phase optics cannot determine the genus and species of individual bacterial cells. The purpose of this study was to use monoclonal antibodies in an immunoenzyme technique to stain spirochetes in dental plaque. Separate mAb were used to estimate total spirochetes and relative numbers of 2 distinct types of Treponema denticola. Plaque samples were collected from 40 subjects grouped by age. Results showed that older subjects are more likely to have spirochetes, to have more spirochetes and to have more diverse populations or spirochetes than younger subjects. Our studies suggest that T. denticola may be the first treponeme to colonize the primary dentition, that T. denticola appears to comprise a major proportion of all spirochetes at all ages and that two distinct serotypes of T. denticola are found to coexist in plaque from most children.

Adolescent↗
PubMed1991

Anti-Kell in pregnancy.

A review of data on haemolytic disease of the newborn (HDN) collected in Newcastle upon Tyne over 25 years revealed 194 pregnancies in which anti-Kell was the only antibody detected. Sixteen affected babies were born. None was hydropic, three had very severe disease but all survived. There were also three stillbirths, none of which had post-mortem appearances of HDN. The highest recorded anti-Kell titres in individual patients ranged from 1/1 to 1/2048 and bore no relation to the severity of the disease. Of the eight pregnancies in which amniotic fluid examination predicted a high risk of stillbirth, half resulted in unaffected babies. We suggest that haemolytic disease caused by anti-Kell is less severe than suggested by some workers. The use of guidelines developed from the study of Rhesus disease to determine the need for intervention in women with anti-Kell may be inappropriate.

Amniotic Fluid↗
PubMed1986

Sexual activity in girls under 16 years of age.

Data on pregnancy, abortion, sexually transmitted disease and cervical dysplasia in girls under the age of 16 years were collected from British and American publications. Over half the pregnancies in girls under 16 ended in induced abortion, and those that continued had increased maternal and perinatal mortality, partly due to failure to attend for care. A prospective study in young teenagers found a high rate of fetal loss in pregnancies that followed abortions. Apart from an increased risk of cervical injury, abortion in girls under 20 carried the same risk of complications as for the American population as a whole. The risk of developing carcinoma of the cervix was doubled in women who began sexual activity before the age of 17 and a large survey found that 1.9% of the girls aged between 15 and 19 years had abnormal cervical cytology. Discouraging sexual activity before the age of consent seems to have a medical as well as a moral basis.

Abortion, Legal↗
PubMed1985

Some aspects of late abortion for congenital abnormality.

Present methods of prenatal diagnosis are not applicable until at least 16 weeks of gestation. Most abortions for suspected congenital abnormality are therefore usually done in the second trimester of pregnancy. Abortions at over 20 weeks of gestation account for about 0.8% of all abortions for residents of England and Wales, but the operations are unpleasant and carry a significant morbidity. Screening the population for neural tube defects has led to a marked reduction in the recorded incidence of infants born with the condition. A survey in the Northern Region of England, with official statistics from Scotland, shows that in spite of the contribution made by selective abortion, there appears to be a genuine reduction in the population incidence of neural tube defect in Scotland. The diagnosis of chromosomal abnormalities, and to a lesser extent of neural tube defects, depends on amniocentesis and there is evidence of more delay in initiating amniocentesis for neural tube defect than for chromosomal tests, probably because of administrative delay associated with the use of serum alphafetoprotein screening. The possible impact of proposals to change the law concerning the limit of viability of the fetus on the practice of late abortion for congenital abnormality is examined. Abortion for congenital abnormality should be permitted after 22 weeks' gestation.

Abortion, Induced↗
PubMed1977

Home and hospital confinement in Newcastle upon Tyne, 1960 to 1969.

During the decade 1960 to 1969, perinatal mortality rates in Newcastle upon Tyne fell in parallel with national trends, in association with a marked reduction of domiciliary midwifery. Analysis of the records of women booked for confinement at home or in specialist hospitals showed that the reduction of mortality occurred with unexpected uniformity in both categories, in low risk as well as high risk patients, and in all causes of mortality except congenital malformations. It could not be attributed to improvements in maternal characteristics nor to increased size of babies at birth. The most probably explanation seems to be a combination of many improvements in the quality of care, with increased awareness of risks, better selection of high-risk groups, and improved supervision and management throughout. There is no indication that single factor in obstetric management, such as more intervention during labour, had a dominant effect.

Birth Weight↗
PubMed1976

Massive chronic feto-maternal bleeding associated with placental chorioangiomas.

After pregnancy complicated by polyhydramnios and the antenatal discovery of a very large placenta a newborn infant suffered from anemia, thrombocytopenia and hypoproteinemic edema, and was successfully treated by exchange transfusion. The placenta contained two chorioangiomas and there was diffuse placental hypertrophy with edema and patchy chorioangiomatosis. There was evidence of major chronic feto-maternal bleeding which could be the explanation for most of the hematological and biochemical problems which occurred. The child was developing normally at subsequent follow-up aged 15 weeks.

Anemia↗