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Biomedical subjects

D W Cox

Publications and source records attributed to D W Cox.

At least 199 records · Page 11Linked to original sources

Rheumatoid arthritis and alpha-1-antitrypsin.

The genetic types of alpha1-antitrypsin (Pi types) were studied in 55 adults with classical or definite rheumatoid arthritis and 56 children with juvenile rheumatoid arthritis. A comparison was made with control groups of 211 healthy adults and 512 schoolchildren. Pi types MZ and SZ were significantly more prevalent in adults with rheumatoid arthritis than in the control adults. There was no difference between the patients with juvenile rheumatoid arthritis and the control children. Reduced concentrations of alpha1-antitrypsin, as associated with heterozygotes for the Z allele, may be a contributory factor to the development of rheumatoid arthritis or to the tissue destruction of rheumatoid arthritis.

Adolescent↗

Liver disease associated with alpha1-antitrypsin deficiency in childhood.

Liver disease in children with alpha1-antitrypsin deficiency and protease inhibitor type ZZ does not necessarily carry a bad prognosis. Fourteen of our 18 patients presented with the neonatal hepatitis syndrome and four had hepatomegaly without jaundice. Although four patients have died of cirrhosis and its complications, and three have severe liver disease, most of the 11 others, of whom four are over 13 years of age, have relatively little clinical, biochemical, or histologic evidence of liver disease. Persistent elevation of SGOT during the third year of life and renal or pulmonary problems were associated with a poor prognosis. Liver biopsy early in the course of the disease was not helpful prognostically but was useful in assessment of the severity of liver disease and demonstration of alpha1AT storage, alpha1AT deficiency was found in 29% of our patients who presented with the neonatal hepatitis syndrome. One of seven apparently healthy Pi type ZZ sibs of our patients had significant liver disease which had not been suspected previously.

Adolescent↗

The genetics of and associated clinical findings in humero-radial synostosis.

This paper compares the manifestations of sporadic, dominantly inherited and recessively inherited humero-radial synostosis with the aim of determining ways of separating these forms on clinical grounds. The genetic forms are characterized by bilateral involvement and by lack of the distal ulnar malformations and the absence of digits that are common in the sporadic cases. The majority of patients with the dominantly inherited form have a characteristic pattern of anomalies, including brachymesophalangy, and the recessive cases have a high frequency of malformations in addition to those of the limbs. Consanguinity is frequent in the families of recessive cases. Four additional patients are presented; two of them illustrate many of the features of the phocomelic syndrome reported by Herrmann et al. (1969). A possible teratogenic cause of these cases is discussed.

Abnormalities, Multiple↗

Protease inhibitors in patients with chronic obstructive pulmonary disease: the alpha-antitrypsin heterozygote controversy.

A group of 163 patients with chronic obstructive pulmonary disease, from the pulmonary service of a large urban hospital, were evaluated for their protease inhibitor (Pi) type by starch gel and crossed immunoelectrophoresis, for serum concentrations of alpha1-antitrypsin and alpha1-antichymotrypsin, and for pulmonary function. Of the patients with emphysema, 17.8% were of Pi type Z; 50% of these were less than 45 years of age, compared to 13% of those of Pi type M. Of all patients with chronic obstructive pulmonary disease, 4.9% were of Pi type Z; 4.9% of patients were of Pi type MZ (heterozygotes) compared with 1.9% of the control population. There was an increased incidence of chronic obstructive pulmonary disease in persons of Pi type MZ, but no increase in persons of Pi type MS. Concentrations of both alpha1-antitrypsin and alpha1-antichymotrypsin were increased and were correlated. No patient had a deficiency of alpha1-antichymotrypsin.

Adult↗

Perturbations of the human menstrual cycle by oxymetholone.

The luteolytic activity of oxymetholone, and anabolic steroid, has been evaluated in 10 women. Administration early in the follicular phase of the cycle inhibited ovulation and prolonged the duration of the cycles in 2 of 3 subjects, but treatment beginning on Day 10 (3 subjects) did not prevent ovulation, although subsequent plasma progesterone concentrations were reduced. Treatment after ovulation (4 subjects) suppressed progesterone levels by 50 to 80 per cent and shortened cycle length by 6 to 8 days. Side effects were weight gain and bromosulfophthalein retention. The most likely mechanisms producing these perturbations are the inhibition of luteinizing hormone release early in the cycle and, later, inhibition of progesterone biosynthesis.

Administration, Oral↗

The effect of neuraminidase on genetic variants of alpha anitrypsin.

Sera of Pi types M, F, S, Z, IM, FM, MS, and MZ were incubated with neuraminidase and the reaction products followed by electrophoresis. The alpha1 antitrypsin components showed a series of changes in mobility as sialic residues were removed. Removal of sialic acid was confirmed by chemical assay. Results of studies with two different electrophoretic systems suggested that the Z type alpha1 antitrypsin has less sialic acid than the M, F, and S types. There was no evidence that other genetic variants have a reduced sialic acid content. The two major bands of alpha1 antitrypsin seen in certain electrophoretic systems may reflect a difference of one sialic acid residue. It is proposed that the Z protein lacks a carbohydrate chain with two terminal sialic acid residues. This carbohydrate deficiency results in lack of secretion of type Z alpha1 antitrypsin from the endoplasmic reticulum, perhaps because of binding to sites specific for the incomplete glycoprotein or because of aggregation of the Z asialo protein. A carbohydrate chain could be prevented from attaching to the Z type either because of a conformational change or because of the replacement of a carbohydrate-binding asparagine residue in the Z protein.

Alleles↗

[Alpha-1 antitrypsin deficiency: correlation between biochemical tests and phenotypes in one family].

Phenotypes (Pi) for serum alpha-1 antitrypsin (AAT) were determined in a family of 19 members spanning three generations and presenting a deficiency in this protein. The standard Fagerhol crossed immunoelectrophoresis procedure was used for this purpose. The individual phenotypes consisted of seven MM, three ZZ, five MZ, one SZ and three MS. AAT levels were obtained by radial immunodiffusion, trypsininhibitory capacity measurements and from cellulose acetate electrophoresis. Good correlation was found between the phenotype and the three biochemical methods for demonstrating the normal phenotype MM and the severe deficiency state ZZ. Some discrepancies were observed for the heterozygotes. It is concluded that these various assays are inaccurate for the interpretation of intermediate AAT concentrations. Since Pi typing is not suitable for use on a routine basis, it is suggested that this analysis should be performed by a specialized laboratory if intermediate deficiency is suspected.

Adolescent↗