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Biomedical subjects

J D Mathews

Publications and source records attributed to J D Mathews.

At least 91 records · Page 5Linked to original sources

Diabetic surveys in Papua New Guinea - results and implications.

Glucose intolerance was found in 22% of the residents of Koki in Port Moresby, 5% of residents in the coastal village of Kalo and in 3% of 120 young civil servants. The respective prevalences of frank diabetes mellitus were 15.6%, 1% and 0%. Cholesterol and triglyceride levels were similar and low in all groups, despite both obesity and glucose intolerance in the urban-Koki residents who also had a significantly higher blood pressure. There is a need to identify those areas of Papua New Guinea where, in a similar fashion to other countries in the South Pacific, diabetes mellitus is increasing. Simple measures of dietary restriction and increased exercise may be effective in preventing diabetes from becoming a major health problem particularly in identified high prevalence areas.

Adolescent↗

Interaction of HLA and Gm in autoimmune chronic active hepatitis.

An immunogenetic study of autoimmune chronic active hepatitis (CAH) showed the relative risk (RR) for this disease was 11.6 for patients who were HLA-B8, 11.7 for patients who were DR3 and 2.3 for patients who were Gma+x+. Moreover, the Gm haplotype Gma+x+ was present in 18 of 40 (45%) patients with HLA-B8, but in none of 10 patients negative for HLA-B8, whereas in 180 healthy controls Gma+x+ was evenly distributed among those positive (24%) and negative (18%) for HLA-B8. The RR was lowest in patients lacking HLA-B8 but positive for Gma+x+. Relative to this low-risk group, the risk was increased 39 times in subjects with both HLA-B8 and Gma+x+, 15 times in subjects with HLA-B8 who were not Gma+x+ and twice in subjects who were neither HLA-B8 nor Gma+x+. Statistical analysis indicated that the three-factor effect (disease risk affected by non-additive effects of HLA-B8 and Gma+x+) was significant (P less than 0.01), as were the main effects of HLA-B8 (P less than 0.001) and Gma+x+ (P less than 0.02). Thus in the presence of HLA-B8, genes linked to Gma+x+, an immunoglobulin CH allotype, may contribute to the development of autoimmune chronic active hepatitis; in the absence of HLA-B8 these same genes appear to be inactive. This may indicate interactions between MHC gene products and VH gene products in the presentation and recognition of autoantigen(s) in autoimmune hepatitis.

Autoimmune Diseases↗

Interactive effect of Gm allotypes and HLA-B locus antigens on the human antibody response to a bacterial antigen.

Two hundred healthy adults were immunized with 1 microgram of the bacterial antigen monomeric flagellin from Salmonella adelaide, and grouped as responders and non-responders on the basis of a rise in titre of antibody 2 weeks after immunization. Immunoglobulin allotypes G1m(a), G1m(z) and G3m(g) were more frequent among responders who made immunoglobulin (Ig)G antibody (P less than 0.02), and HLA-B12 was more frequent among responders who made IgM antibody (P less than 0.05). The mean log titre of IgG antibody was higher in females (P less than 0.001), in subjects with T1m(a), G1m(z) and G3m(g) allotypes (P less than 0.05), and in Gm heterozygotes (P less than 0.01). The mean log titre of the IgG antibody response in subjects with particular Gm phenotypes was also dependent on the HLA-B locus phenotypes HLA-B7, B8 and B12 (P less than 0.005); for example, among those with the phenotype Gm(a-x-b) subjects with HLA-B7 were low responders and those with HLA-B8 were high responders. These findings are consistent with the hypothesis that there are immune response genes within the major histocompatibility complex (MHC) which interact with Gm-linked genes in determining levels of serum antibodies of different isotypes and specificities.

Adolescent↗

The immune response to vasectomy and its relation to the HLA system.

We examined 188 men who had undergone vasectomy up to 6 years previously and, for comparative purposes, 100 men who were about to undergo the operation. Blood specimens were available from a total of 283 men. Sperm antibody assays using immunofluorescence, microagglutination, and microimmobilization confirmed that the prevalance of several types of antibody is higher after vasectomy. Immobilizing and agglutinating antibodies appeared to be the most important. Trends in antibody prevalence according to the time after the operation were analyzed. Screening against lymphocytes and lymphoid lines showed that the anti-sperm activity of era was not related to anti-HLA or anti-Ia activity. Associations were examined between different types of sperm antibody, and between these antibodies and autoantibodies to other antigens. When antibody prevalence was studied in relation to HLA types, the HLA antigen A28 was found to be strongly associated with production of head agglutinating antibody (and immobilizing and immunofluorescent equatorial antibodies) after vasectomy. This is one of the first clear-cut examples of antibody production associated with the HLA system.

Acrosome↗

Association of HLA antigens with glucose intolerance following renal transplantation.

Records of 109 renal transplant patients were reviewed to test the hypothesis that post transplant glucose intolerance would be associated with "diabetic", HLA antigens (HLA--B8, B18, Bw15 and Bw16). Of 42 patients with significant glucose intolerance, 23 had one or more of these antigens (RR=2.65, P=0.01). These findings suggest that stress or drug treatment associated with renal transplantation can induce glucose intolerance in patients with a "diabetic" gene associated with the HLA--B locus.

Cadaver↗

HLA patterns in pernicious anaemia.

The pattern of HLA antigens was studied in 127 patients with Addisonian pernicious anaemia. The pattern in the whole group of patients differed significantly from that in 586 controls. But different subgroups of the patients had different HLA antigens. Among 27 patients with anaemia associated with endocrine disease there was an increased frequency of HLA-B8, B18, and BW15. The remaining 100 patients, who did not have endocrine disease, showed increased frequencies of HLA-B7 and B12. The positive association with HLA-B12 among this subgroup was confined to 62 patients with severly impaired vitamin B12 absorption, including 13 patients with vitamin B12 neuromyelopathy, who had the highest frequencies of HLA-B7 and B12. The significant heterogeneity in HLA patterns in different clinical subgroups of these patients indicates genetic heterogeneity in pernicious anaemia and explains previous discrepancies in the associations between HLA antigens and pernicious anaemia.

Anemia, Pernicious↗

Carcinoembryonic antigen in renal allograft recipients and immunosuppressed renal patients.

Carcinoembryonic antigen (CEA) was estimated in plasma from 70 patients with a renal transplant, 105 patients with glomerulonephritis who had received immunosuppressive therapy, and 124 healthy controls. There were raised levels in 30% of those with a renal transplant, 10% of those with glomerulonephritis and 2% of controls, and levels were higher in current smokers. CEA levels did not correlate with pre-transplant dialysis time nor with serum creatinine levels, but tended to fall with increasing time after transplantation, especially in non-smokers. CEA levels did not correlate with prednisolone dosage nor with number of rejection episodes, after allowing for time after transplantation and smoking habit. Nine of 70 patients with a renal transplant and three of 105 with glomerulonephritis had cancer, of skin in seven, cervix uteri in four, and colon in one. CEA was raised in all four transplant recipients with a visceral cancer (cervix three and colon one), but in none of the five with cutaneous cancer. Raised CEA levels occurring late after a renal allograft should prompt a careful search for visceral cancer.

Adolescent↗

Cancers of the lung and nasal sinuses in nickel workers: a reassessment of the period of risk.

Nine hundred and sixty-seven men who were employed in a nickel refinery in South Wales on at least two occasions five or more years apart before 1945 have been followed up, and the mortality rates from different causes related to the date of their first employment. Previous reports suggested that the occupational risks of lung and nasal sinus cancer had been eliminated by 1925. It is now shown that the risk persisted until 1930, which accords better with the temporal changes in the process.

Dust↗

HLA and the sudden infant death syndrome.

HLA phenotypes of 66 parents of 33 infants succumbing to the sudden infant death syndrome (SIDS) were determined using a standard microlymphocytotoxicity method. Heterogeneity testing over all locus antigens revealed a significant difference between the parents and a control group consisting of blood donors and healthy unrelated volunteers. This heterogeneity was still evident when maternal and paternal groups were considered separately with the controls and when compared with each other. Individual A locus antigens displaying frequency deviation from control values included A9 (decreased in husbands), A10 (increased in wives and total parent group), and A28 (increased in wives). The increase in frequency of A10 became highly significant when only parents of children with evidence of laryngitis at post mortem were used for comparison with control values. No difference in B locus antigens between any of the groups was observed. The results obtained are compatible with the view that SIDS is the result of a hypersensitivity reaction to one or more allergens and that genes coding for these specific responses are linked to the HLA complex. Differences observed between the maternal and paternal groups may be explained on the basis of maternal antibody, passively acquired by the infant, which serves a protective role in the respiratory tract, prior to the development of immunocompetence. The production of these antibodies is also dependent on genes linked to the maternal HLA complex.

Female↗

Weak autoantibody reactions to antigens other than sperm after vasectomy.

Autoantibody activity against various antigens was measured by indirect immunofluorescence in 97 men about to undergo vasectomy and 170 men who had undergone the operation up to six years earlier. There was a significantly higher prevalence of weakly positive autoantibody reactions among those who had undergone vasectomy. There was, however, no evidence that vasectomy could induce stronger autoantibody reactions such as those associated with autoimmune disease.

Adult↗

Hormonal assessment before and after vasectomy.

Animal experiments have suggested that vasectomy may disturb the endocrine function of the testis. To explore this possibility in man blood was obtained from 277 men who had undergone vasectomy up to six years earlier or who were about to undergo the operation. Mean plasma testosterone concentrations seemed to be slightly higher in those who had undergone vasectomy than in the preoperative group, although this difference was not statistically significant. There was no significant difference between these two groups in the concentrations of luteinising hormone, follicle-stimulating hormone, prolactin, or oestradiol.

Adult↗