Effect of maternal and infant covariates on sibship correlation in birth weight

Birth weight on 12,644 singleton infants from 6,196 sibships born in Maryland between 1980 and 1984 were used to estimate the effects of nine maternal and infant covariates on the sibship correlation in birth weight. Assuming a homogeneous correlation across all families, the estimated intraclass correlation was 0.4664 (+/- 0.0099). This high sibship correlation makes it possible to predict, with reasonable accuracy, the birth weight of a child given information on previous sibs, as well as covariates on the mother and/or infant pertinent to a given pregnancy. The reduction in variance associated with incorporating information on the nine covariates used here was approximately equal to that obtained by conditioning on a single previous sib. Testing for heterogeneity in correlation among different groups of families showed that a crude measure of parity (first live birth vs. other), time between births, mother's marital status, and maternal age at the birth of the last child significantly influenced the sibship correlation in birth weight.     

Morphology of corticotectal cells in the primary visual cortex of hooded rats

In primary visual cortex of hooded rats, pyramidal cells in layer V may be classified as long, medium, or short, on the basis of the layer in which the apical dendrite terminates. The present study determines which of these types of pyramidal cells project to the superior colliculus. Two different strategies were used to label corticotectal cells with horseradish peroxidase (HRP). In the first set of experiments, a large number of corticotectal cells were labeled by retrograde transport following injection of HRP into the superior colliculus. In the second set of experiments, single unit recording was used to identify corticotectal cells physiologically by antidromic activation from the superior colliculus. These cells were then impaled and labeled by intracellular iontophoresis of HRP. The results from both techniques suggest that only long pyramidal cells send an axon to the superior colliculus. These cells are distinguished by an apical dendrite that extends into layer I. We conclude that in hooded rats corticotectal cells in primary visual cortex are the long pyramids in layer V.     

FEASIBILITY OF CONDUCTING CARDIOVASCULAR OUTCOME RESEARCH IN AUSTRALIAN GENERAL PRACTICE: RESULTS FROM THE ANBP2 PILOT STUDY

1. The present study aimed to determine the feasibility of conducting a 5 year cardiovascular outcome trial of the treatment of 6000 elderly hypertensive patients in Australian general practices. 2. General practitioners (GPs) were invited to participate by mail and personal follow-up. Patient records were reviewed to identify subjects for a blood pressure (BP) screening programme. Blood pressure was measured on three occasions and eligible subjects were included if the average BP was 160 mmHg systolic or 90 mmHg diastolic if systolic BP was 140 mmHg. 3. Seven hundred and forty-one GPs were approached and 89 were enrolled in the study (12% of mail invites and 75% of those receiving a personal contact). In 16 practices where screening was completed, 82 000 records were reviewed to identify 4% patients eligible for screening. Twenty-two per cent of eligible subjects attended screening. Of 1938 subjects screened, 180 (9%) had BP 5=160/90 mmHg. Forty-seven percent of subjects (n = 916) were receiving antihypertensive therapy and 184 (20%) were withdrawn from therapy. One hundred and sixteen (63%) of these subjects had BP return to study entry levels within 6 weeks. Fifty-seven newly diagnosed and 81 previously treated subjects were randomized (7% of the screened population). 4. Based on the high participation rate of GPs, the response rate of patients to attend a BP screening programme and the 7% randomization to screening ratio for entry into the study, the ANBP2 pilot study has demonstrated that it is feasible to recruit subjects from Australian general practices to a cardiovascular outcome trial.     

Chondrons from articular cartilage. III. Morphologic changes in the cellular microenvironment of chondrons isolated from osteoarthritic cartilage

Chondrons were isolated from human and canine osteoarthritic cartilage using low-speed homogenization techniques. Changes in chondron morphology were evaluated using differential interference-contrast microscopy, phase-contrast microscopy, and histochemical and ultrastructural methods. Chondrocyte viability was assessed using fluorescein diacetate staining, and chondron metabolism was investigated using autoradiography. The results suggest that initial changes in the collagen and proteoglycan distribution within the chondron are followed by chondrocyte proliferation to form clusters. These techniques offer the potential to study cell matrix interactions in degenerative osteoarthritis.     

Is the message getting through? Nutritional knowledge of pregnant women in Edinburgh and London

This paper reports the results of a survey in which pregnant women in London and Edinburgh were asked about their knowledge and understanding of the recent recommendations of expert committees (James, 1983; DHSS, 1984). In general, Londoners had a better understanding, although in both regions manual groups were less knowledgeable, with the Edinburgh manual group the least well informed.     

Localisation of a pulmonary autoantigen in cryptogenic fibrosing alveolitis.

BACKGROUND--Cryptogenic fibrosing alveolitis (CFA) is believed to have an immunological pathogenesis with a persisting inflammatory reaction to an as yet unidentified pulmonary antigen(s). A high frequency of IgG autoantibodies has previously been found in the plasma of patients with CFA to an extractable 70-90 kDa lung antigen by Western blotting. Preliminary immunohistochemical studies with patient IgG had indicated that the target protein(s) might be associated with alveolar epithelial lining cells which have previously been suggested as the site of immunological attack in CFA. METHODS--In order to confirm this finding immunohistochemical analysis and Western blotting were performed on a human type II alveolar cell line (A549) using CFA patient plasma. In order to study further the distribution of the antigen, antibodies were raised in a rabbit to the partially purified 70-90 kDa CFA lung protein. RESULTS--The results showed that the human CFA autoantibody recognised a 70-90 kDa protein with a cytoplasmic distribution present in the A549 cells, confirming previous observations. The immune rabbit IgG recognised a protein of similar molecular weight by Western blotting of protein derived from lung biopsy samples of patients with CFA and A549 cells. In addition it immunoprecipitated protein(s) of this molecular weight from lung biopsy protein extracts from patients with CFA. The precipitated protein(s) were found to cross-react with the autoantibody found in the plasma of patients with CFA. Immunohistochemical analysis with immunised rabbit antibody revealed positive staining of type I and II alveolar epithelial lining cells in CFA. A similar pattern of epithelial staining was also observed with the rabbit IgG on biopsy specimens of lung from patients with sarcoidosis and control lung tissue, although this was more focal and less intense. No positive staining was seen on sections from a number of non-pulmonary tissues (colon, liver, kidney, tonsil, lymph node, skin, cervix). Cytoplasmic staining of the A549 cell line was also detected. CONCLUSIONS--The 70-90 kDa protein recognised by autoantibodies in patients with CFA is associated with pulmonary epithelial lining cells. The immune rabbit IgG produced appears to recognise antigen by Western blotting and immunohistochemical staining of lung tissue in a similar pattern to the patient autoantibodies. Immunohistochemical data obtained with this antibody suggest that the putative autoantigen against which patients with CFA mount a humoral immune response may be endogenous and specific to the lung.