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Biomedical subjects

J J Marx

Publications and source records attributed to J J Marx.

At least 163 records · Page 9Linked to original sources

Characterization of synthetic medium antigens of Micropolyspora faeni and Thermoactinomyces candidus.

A synthetic (Syn) medium was developed for growth of Micropolyspora faeni and Thermoactinomyces candidus, and optimum conditions for culture filtrate antigen production were found to be 3 days for T. candidus and 9 to 12 days for M. faeni. Appearance of proteolytic activity in the culture fluid supernatant coincided with a decrease in precipitating antigen content, protein content, and number of proteins on polyacrylamide gel electrophoresis (PAGE), probably as a result of proteolysis. The results suggest that protein content, number protein bands on PAGE, and proteolytic activity are predictive of precipitating antigen content. Antigens prepared in Syn medium were compared to those produced by the double-dialysis procedure and found to contain adequate amounts of antigenic material of sufficient quality to warrant clinical studies of their usefulness in the diagnosis of hypersensitivity pneumonitis.

Animals↗

Precipitating antibodies to farmer's lung antigens in a Wisconsin farming population.

The prevalence of farmer's lung disease and antibodies to farmer's lung antigens were studied in a probability sample of over 1,400 farmers in north central Wisconsin. The prevalence rate of farmer's lung disease was 4.2 per 1,000 farmers. The most prevalent antibody type was directed against Micropolyspora faeni, with 6% of the study population precipitin-positive. Prevalence of antibodies to M. faeni was associated with dairy farming, larger farms, and larger dairy herds. An additive effect of hay acreage and size of dairy herd was observed. An independent relationship was also observed for cigarette smoking, with antibodies to M. faeni more prevalent among nonsmokers.

Adolescent↗

Angiotensin-converting enzyme in farmer's lung.

Serum levels of angiotensin-converting enzyme were measured in a group of patients with farmer's lung and a group of precipitin-positive subjects with no history of farmer's lung. The levels did not differ significantly from control subjects matched for age and smoking history. The mean serum level of angiotensin-converting enzyme in a group of acutely ill patients with farmer's lung was significantly reduced. An acute challenge of three patients with Micropolyspora faeni did not produce an increase in serum levels of angiotensin-converting enzyme. These studies suggest that an increased serum level of angiotensin-converting enzyme can be a diagnostic aid in making a differential diagnosis between sarcoidosis and farmer's lung.

Antigens, Bacterial↗

HLA-B8 in sarcoidosis.

One hundred and seventy-four unrelated white patients with biopsied and clinically diagnosed sarcoidosis and a reference population of 97 were tested for HLA antigens. Selected comparisons showed a statistically significant association of HLA-B8 with the sarcoidosis group (28.9%) when compared to the reference group (15.5%).

Chromosome Mapping↗

Mucosal uptake, mucosal transfer and retention of iron: reproducibility of their measurement by whole-body counting and differences between Fe(II) and Fe(III).

Iron absorption was measured with a double isotope technique which enabled investigation of initial mucosal uptake, mucosal transfer and retention of iron. Radioactivity was measured with a whole-body scanner. Absorption of 1 mg Fe2+ was studied twice in 22 healthy subjects, with an interval of almost two years. No significant difference was observed in the mean values of mucosal uptake, mucosal transfer and retention of iron. In some subjects, however, values differed considerably, despite identical experimental conditions, detailed instruction and no detectable changes in the individual iron status. In another 10 subjects absorption of 1 mg Fe3+ was compared with 1 mg Fe2+. Mucosal uptake and retention of Fe2+ were twice as high as of Fe3+ while mucosal transfer did not differ significantly. It appears that investigations of groups of subjects, receiving either the same or a different iron test dose, give reliable and reproducible results. Individual and longitudinally studied values in a single subject, however, have to be interpreted with caution.

Aged↗

Immunology of clinically inactive sarcoidosis: serum factors.

Sera from 84 white patients with inactive sarcoidosis were analyzed for immunoglobulins, complement, autoantibodies, alpha 1-antitrypsin and lysozyme. The levels of serum factors were compared with levels in serum from a reference population which was matched for age, sex, ethnic background and geographic location. IgG, IgA, IgD, and C3 levels were similar for both groups, as were frequencies of rheumatoid factor, antinuclear antibody and anti-DNA antibody. Lysozyme levels were significantly lower in the inactive sarcoidosis group but the acute phase reactants alpha 1-antitrypsin, IgM as well as complement consumption were increased. The data suggest that the underlying etiological events of sarcoidosis continue, albeit at a subclinical level.

Adult↗

The effect of lithium carbonate on lymphocyte, granulocyte, and platelet function.

Lithium affects an increase in granulocyte counts in humans and has been promoted in the treatment of granulocytopenia and as adjuvant cancer chemotherapy to reduce the incidence of bacterial infections. In this study, eight healthy volunteers were studied by means of a panel of quantitative and cellular function tests before and after a seven-day course of lithium carbonate. Granulocyte, lymphocyte, and platelet function was assessed by the test panel. This panel included T cell and B cell enumeration, lymphocyte transformation to a number of mitogens and antigens, phagocytic and bactericidal activities of peripheral leukocytes, nitroblue tetrazolium (NBT) reduction, chemotaxis, chemiliminescence, platelet aggregation studies, and Ivy bleeding time. The was a significant reduction in bactericidal capacity (p less than 0.005) and a significant reduction in lymphocyte response to PPD (p less than 0.01). Although lithium increase the granulocyte count, the reduction in bactericidal capacity of granulocytes may reduce the beneficial effect of the granulocytosis. Prospective clinical studies are indicated to assess the clinical efficacy of the drug.

Blood Platelets↗

Inhibition of platelet aggregation with histamine.

A sensitive in vitro technique was used to demonstrate the inhibitory effects of histamine or human blood platelets. Platelet aggregation by epinephrine was completely inhibited at 10(-3) M concentrations of histamine. Persistent elevations of cyclic AMP levels were shown to occur in the platelets when histamine was added and corresponded to the inhibitory effects on platelet aggregation. In contradistinction to the analogous inhibitory effects by histamine on other cellular elements of the hematopoietic system, this inhibitory effect on platelets could not be blocked by equimolar concentrations of either of the classes of histamine antagonists presently available. It is suggested that there may be other additional histamine receptors on the surface of membranes of platelets or that histamine mediated its inhibitory effect on platelets through a mechanism other than surface receptors.

Blood Platelets↗

Antibody-independent complement consumption by Micropolyspora faeni.

Micropolyspora faeni is an etiologic agent of hypersensitivity pneumonitis, a disease with an ill-defined mechanism of pathogenesis. Many reports have suggested an immunologic mechanism. A number of laboratories have demonstrated a nonantibody-mediated activation of the complement cascade. This study was undertaken to define the pathway of the complement consumption induced by M. faeni. We utilized an extract of M. faeni grown on synthetic media rather than the more common double dialysis extracts. Complement consumption by this extract was easily demonstrable in the absence of detectable antibody, but was inhibited by EDTA and MgEGTA. With the exception f C1, all of the early components of the classical pathway were markedly reduced following incubation of normal human serum with this extract. C1 was poorly consumed. In addition, factor B conversion to B was not inhibited by 10 mM MgEGTA suggests that the alternative pathway may also be affected. The generation of M. faeni-dependent chemotactic factor(s) from serum demonstrates that the complement cascade is being activated rather than inhibited.

Antibodies↗

Serologically detectable HLA-A, B, and C loci antigens in farmer's lung disease.

The frequency of serologically detectable (SD) HLA-A, B, and C loci antigens in subjects with farmer's lung disease (N = 100) was compared with that of age- and sex-matched normal normal farmers with no precipitating antibodies to extracts of thermophilic actinomycetes. A subset of the farming population with antibodies to the thermophilic actinomycetes and no evidence of clinical disease (N = 55) was also agae- and sex-matched to the farmer's lung disease population. No significant associations between any of the SD HLA antigens tested and farmer's lung disease were found in the study. The data demonstrated that there was no association between SD HLA antigens and farmer's lung disease in random populations.

Actinomycetales↗

Simultaneous measurement of 59Fe and 51Cr in iron absorption studies using a whole-body scanner with mobile shielding.

A whole-body scanner is described with a mobile shadow shield which affords a considerable reduction in space. The scanner has two NaI(T1) scintillation crystals of 4 x 6", placed at opposite sites of the subject. Background radiation, efficiency and geometric qualities made the scanner very useful for clinical whole-body counting. The equipment was used in iron absorption studies using a double isotope technique with 59Fe and 51Cr. After ingestion of an oral test dose total body kinetics of 59Fe and 51Cr was followed up to 60 days in 4 volunteers. Between days 3 and 10 the 51Cr, which was used as an non-absorbable indicator, had left the body completely. The 59Fe reached a constant value not before day 10, indicating that iron retention cannot be measured before that time. From repeated measurement of 59Fe and 51Cr directly after ingestion until the first defaecation it could be deduced that the coefficient of variation for 59Fe was less than 1.5% with a scanning time of 600 sec, and for 51Cr less than 5%. Extreme variations in geometry, such as measurement of the activity in a beaker and of the same amount after ingestion in the body, yielded practically the same value for 59Fe. The double isotope technique made it possible to measure not only iron retention but also mucosal uptake and mucosal transfer of iron. It is pointed out that measurement of the last two parameters of iron absorption is not possible in patients with serious obstipation or with very low mucosal uptake values.

Adult↗

Mucosal uptake, mucosal transfer and retention of iron, measured by whole-body counting.

A method is described which enables simple and accurate measurement of the separate steps of iron absorption. A double isotope technique was used with 59Fe as a tracer and 51Cr (as CrCl3) as an inert, not absorbable indicator. With a whole-body counter it was possible not only to measure initial mucosal uptake and retention but also to calculate mucosal transfer of iron. Thus faeces collection for determination of mucosal uptake of iron was no longer necessary. Absorption of a physiological dose of inorganic iron was studied in 25 normal subjects (15 males and 10 females), in 21 patients with uncomplicated iron deficiency and in 8 patients with idiopathic haemosiderosis. A significant difference was demonstrated between normals and patients with iron deficiency and in idiopathic haemosiderosis with respect to the various steps of iron absorption. The method provides a simple tool for the study of the regulation of iron absorption at the luminal and intracellular site of the intestinal mucosal cell.

Adolescent↗

Characterization of precipitin response to Micropolyspora faeni in farmer's lung disease by quantitative immunoelectrophoresis.

Sera from 12 patients with farmer's lung disease (FLD) drawn during an acute episode and displaying precipitins to Micropolyspora faeni were analyzed by crossed immunoelectrophoresis with an intermediate gel combined with a rabbit reference precipitate system. Forty-six precipitin arcs were identified in the reference system, and FLD sera reacted with 36 of these antigens. The FLD sera displayed significantly more precipitates and higher precipitin scores when compared with sera from 16 precipitin-positive subjectw who did not have FLD. However, there was overlap between the 2 groups, and neither measurement distinguished the 2 persons who became ill after challenge from one person who did not. Three disease specific antigens were identified that may have special relevance for pathogenesis of disease. Ten exposure-relevant antigens were also identified. We propose that these antigens be important components of a standardized M. faeni antigen preparation.

Chronic Disease↗