Search PubMed⌕ Search

Biomedical subjects

M J Anderson

Publications and source records attributed to M J Anderson.

At least 163 records · Page 9Linked to original sources
PubMed1981

Outcome of asymptomatic infection with rubella virus during pregnancy.

We have tried to detect prenatal infection in 34 infants whose mothers were re-infected with rubella virus during pregnancy and in six infants whose mothers had primary subclinical rubella during pregnancy. Two methods of assessment were used: first, serum obtained soon after birth was tested for IgM antibody; secondly, serum obtained after the age of 8 months was tested for specific IgG. The 34 women with re-infections had increases in IgG antibody titre but no IgM response. No evidence of prenatal infection was found in 33 of their 34 infants. One infant was found to have IgG antibody at the age of 11 months. This infant was IgM-negative at birth and had a rubelliform rash at the age of 5 1/2 months; it therefore probably contracted post- rather than pre-natal infection. Fetal infection from maternal re-infection during pregnancy is probably rare. The six women with primary subclinical rubella produced both IgG and IgM classes of antibody. Three of their six infants showed serological evidence of intrauterine infection. One, infected when its mother was 8 weeks pregnant, had clinical evidence of congenital rubella. Primary subclinical rubella during pregnancy therefore carries a significant risk of fetal infection. Because of the difference in outcome, great care should be taken to distinguish between primary infection and re-infection when investigating symptomless increases in antibody titre after contact with rubella during pregnancy.

Antibodies, Viral↗
PubMed1981

Forced walking prepartum for dairy cows of different ages.

Fifty-three 2-yr-old Holstein heifers and 63 cows from 3 to 7 yr old were exercised 5 days/wk for 8 wk before calving. Three treatments were: 1) control (no forced exercise); 2) walk 1.6 km/day; and 3) walk 8.0 km/day. Exercise was at 4.0 km/h in a circular lane with a motor-driven gate. Daily feed intake and weekly body weights were recorded during the prepartum period and 50 days postpartum. Daily milk production and semimonthly milk composition were recorded for the complete lactation. Exercise did not affect feed intake during the prepartum period. Weight gain was reduced during the dry period, more for older than for young cows, and particularly less gain for the longer distance. There was no benefit to production or feed efficiency from exercise for any age of cows. Production of protein and solids not fat was higher for combined ages of cows on the shorter than the longer distance. Protein percentage in milk for the lactation was higher for exercised than for control cows; solids-not-fat percentage in milk was higher for exercise for shorter than for longer distance; and fat percentage in milk was not affected by exercise. Number of services per conception and number of days open were less for exercised cows.

Age Factors↗
PubMed1981

Long-term results following coronary bypass operation. Importance of preoperative actors and complete revascularization.

The initial 102 patients who underwent aorta-coronary bypass grafting between 1969 and 1971 were followed for a mean of 96 months (minimum follow-up 7 years). Preoperative variables predictive of survival at 5 years were stability of angina, previous heart failure, and left ventricular function. Stability of angina, previous heart failure, previous myocardial infarction, and smoking were important predictors of symptomatic status at 5 years. At operation, 62 patients had anatomic or technically complete revascularization, whereas 40 had incomplete revascularization. There was a significantly improved survival rate in those patients who were completely revascularized. The 5 year survival rate was 84% for completely revascularized patients compared to 96% for incompletely revascularized patient (p less than 0.02). This improvement in survival was continued to 9 years. There was also a significant improvement in asymptomatic status of the completely revascularized patients compared to the incompletely revascularized patients. At 2 years, 75% of the completely revascularized subjects were asymptomatic compared to 45% of the incompletely revascularized patients. However, this difference disappeared after 5 years. Thus complete myocardial revascularization is superior to incomplete revascularization in terms of survival and asymptomatic state. Preoperative variables may be useful in predicting postoperative results.

Actuarial Analysis↗
PubMed1981

Is it important to preserve the chordae tendinae and papillary muscles during mitral valve replacement?

To evaluate the importance of preserving chordae tendinae and papillary muscles to left ventricular function after mitral valve replacement, 12 dogs had Carpentier-Edwards or Björk-Shiley mitral valves inserted. Cardiopulmonary bypass, systemic hypothermia at 25 degrees C and cold cardioplegia were used. The period of anoxic arrest was 30 minutes. In six dogs, mitral valve replacement was performed after complete excision of the mitral valve. In the other six dogs the anterior leaflet was partially excised but all chordae tendinae and papillary muscles were left intact. Hemodynamic measurements, including left ventricular function following volume loading, were made preoperatively and postoperatively. Left ventricular angiograms were obtained postoperatively in all dogs. Preoperatively there was no significant difference in the left ventricular function curves in the two groups, but postoperatively the curves showed significant differences. In the group with preserved chordae tendinae, left ventricular function improved with volume loading to a left ventricular end-diastolic pressure of 20 mm Hg while in the group with divided chordae tendinae, function improved more slowly and ceased to improve after loading to an end-diastolic pressure of 15 mm Hg. The mean left ventricular ejection fraction following mitral valve replacement with preserved papillary muscles was 0.62 +/- 0.01 and with divided papillary muscles was 0.45 +/- 0.05 (P less than 0.05). The authors conclude that it is important to preserve chordae tendinae and papillary muscles when carrying out mitral valve replacement.

Animals↗
PubMed1980

Effect of catabolite repression on chemotaxis in Salmonella typhimurium.

The chemotaxis of Salmonella typhimurium LT2-ST1, grown with different sole carbon sources toward ribose, allose, serine, aspartate, and glucose, was examined. Maximum chemotaxis toward serine, aspartate, and glucose were unchanged with either glucose or citrate as the carbon source. The height of the peak in the ribose response curve was 25% of a standard serine response when the bacteria were grown on citrate. However, when the bacteria were grown on glucose, the ribose response was 1% of the serine standard, and when on glycerol, 5%. Chemotaxis toward allose, a competitive inhibitor of ribose chemotaxis, was similarly affected. The amount of ribose binding protein, the receptor for ribose chemotaxis, was determined in bacteria grown on citrate, glucose, or glycerol. The amount of ribose-binding protein released from cells grown on glucose or glycerol was appreciably less than the amount released from cells grown on citrate. These data suggest that the observed effect on ribose chemotaxis is due to catabolite repression of ribose-binding protein and another component of the chemotactic system.

Carbohydrate Metabolism↗
PubMed1980

Regeneration of spinal electrocyte fibers in Sternarchus albifrons: development of axon-Schwann cell relationships and nodes of Ranvier.

The electrocyte fibers in the gymnotid Sternarchus albifrons are highly differentiated myelinated axons which exhibit several types of nodes of Ranvier and characteristically short internode lengths. In the present study, regeneration of the electrocyte fibers following removal of the tail was examined by electron microscopy. By 36 days following extirpation, the regenerating electrocyte axons exhibit Type I nodes of Ranvier, with a normal morphology, and Type II nodes of Ranvier with a large nonmyelinated gap and a polypoid elaboration of the axon surface. Moreover, in the regenerating axons the internode length: diameter ratios are quite small. Thus, relatively normal axons-Schwann cell relations and a relatively normal differentiation of the axon surface are achieved during regeneration of the Sternarchus electrocyte fibers.

Animals↗
PubMed1980

Fetal infection resulting from maternal rubella after the first trimester of pregnancy.

We have tried to measure the incidence of prenatal infection in 304 infants whose mothers had had rubella at various times after the first 12 weeks of pregnancy. Two methods of assessment were used: first, serum obtained soon after birth was tested for specific IgM antibody; secondly, serum obtained after the age of eight months was tested for specific IgG. When maternal rubella occurred 12-16 weeks after the last menstrual period specific IgM antibody was detected in 28 out of 50 infants (56%). The proportion fell progressively to 12% after maternal rubella at 24-28 weeks, rose to 19% after rubella at 28-36 weeks and then to 58% when the illness occurred during the last month of pregnancy. In all, IgM antibody was detected in 77 out of 260 infants (29%). The fetus can thus be infected at any time during the second and third trimesters of pregnancy, but the risk varies at different stages.The figures for the prevalence of IgG antibody were greater throughout, because some infants had IgG who had previously lacked specific IgM. After maternal rubella at 12-16 weeks IgG antibody persisted in 22 out of 31 infants (71%). The proportion fell to 28% after rubella at 24-28 weeks and then increased progressively to 94% after rubella during the last month. In all, IgG antibody persisted in 94 out of 190 infants (49%). The true rate of fetal infection probably lies between the rates estimated from the presence of IgM antibody and the subsequent prevalence of IgG.Infants whose mothers had rubella at any time during pregnancy should be examined regularly for possible evidence of damage.

Antibodies, Viral↗
PubMed1980

The role of host responses in the recovery of mice from Sendai virus infection.

The antiviral responses in mice to intranasal inoculation with Sendai virus are described. To investigate the relative importance of the humoral, cell-mediated and interferon responses, the pathogenesis of this infection was studied in animals which were immunocompetent, T cell-deprived or immunosuppressed with cyclophosphamide. Treatment with cyclophosphamide converted the mild, self-limiting infection observed in immunocompetent mice into a severe and frequently lethal pneumonic disease. This was associated with an enhanced interferon response but no detectable antibody or cell-mediated immune response. T cell-deprived mice suffer an infection of intermediate severity associated with an increased interferon response, a normal humoral immune response and no cell-mediated immune response. The implications of these results in relation to the role of the antiviral responses in recovery from Sendai virus infection are discussed.

Animals↗
PubMed1980

Interaction of Escherichia coli K88 antigen with porcine intestinal brush border membranes.

The fimbria-associated Escherichia coli antigen, K88, was purified to homogeneity as determined by polyacrylamide gel electrophoresis and immunodiffusion. This polymeric antigen consists of noncovalently linked subunits, containing little or no carbohydrate, and has a monomeric molecular weight of 23,000. When a binding assay employing differential filtration was used, K88 formed complexes with isolated porcine intestinal brush border membranes. The formation of complexes was inhibited by glycoproteins with terminal N-acetylglucosamine and N-acetylgalactosamine residues and to a lesser extent by free N-acetylhexosamines. These amino sugars may play a role in the interaction of this pathogenic strain of E. coli with the intestinal epithelia of pigs.

Animals↗
PubMed1979

Falciparum malaria and pregnancy.

During pregnancy an increase occurs in the prevalence and density of Plasmodium falciparum malaria. The increase relative to non-pregnant women remains fairly constant with age though there is an over-all decrease in prevalence and density in both groups with age. The increase is at a height relatively early in pregnancy and declines after mid-term. At the height of the malaria season in The Gambia less antimalarial antibody appears in cord bloods than in the early dry season when transmission is lower. Infants show an increase in malaria prevalence and density in the early dry season as compared to the mid-wet season while the remainder of the population shows a decrease.

Adult↗
PubMed1979

Comparison of immunofluorescence and radioimmunoassay for detecting IgM antibody in infants with the congenital rubella syndrome.

Immunofluorescence (IF) and radioimmunoassay (RIA) have been compared as methods for detecting IgM antibody in 124 infants with confirmed or suspected congenital rubella. IF was used to test sucrose density gradient fractions and RIA to test fractions and whole serum. When fractions were tested IF and RIA were equally specific and distinguished clearly between IgM and IgG, but RIA was the more sensitive method. The RIA titre in whole serum was always greater than in the peak IgM fraction and there was no evidence that testing the serum, rather than the fraction, could result in failure to detect IgM. With some sera RIA gave low titres which became negative after absorption with IgG-coated latex beads. The mechanism of this 'false positive' effect, which may have been due to IgM with anti-IgG activity, was not investigated, but if it can be removed by absorption it need not reduce the specificity of the test. During the first 6 months of life IgM antibody was detected by RIA in 30 out of 32 unfractionated sera and by IF in fractions from 28 of these. After the age of 6 months IgM was found progressively less frequently and the greater sensitivity of RIA became a more obvious advantage: 17 out of 60 specimens were positive by RIA and 11 of these were negative by IF. RIA testing of whole serum appears to be an economical, specific and sensitive method for detecting IgM antibody in congenital rubella, of particular value when the titre of antibody is low.

Age Factors↗
PubMed1979

Competency: the what, why, and how of it.

Competency is a frequently used term in the physical therapy profession, but many physical therapists are unclear about its definition and its meaning in professional activity. This article describes the operational definition of competency as used in the practice of physical therapy by members of the Association; describes the development of the manual, Competencies in Physical Therapy: An Analysis of Practice; offers direction in possible uses of the manual; and suggests future uses for the manual in Association activity.

Clinical Competence↗
PubMed1979

The nature of the effector cells of cell-mediated immune responses to Sendai and Kunz virus infections in mice.

The development of virus-specific cell-mediated immune (CMI) responses to Sendai and Kunz virus infections of the respiratory tract of mice is described. In addition a heterotypic cell-mediated immune response develops during each of the virus infections. Cell depletion studies indicate that the effector cells of the virus-specific CMI responses are theta antigen bearing T lymphocytes. Similar studies of the heterotypic responses suggest that 2 cell types are involved, T lymphocytes and NK cells.

Animals↗