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Biomedical subjects

J Metz

Publications and source records attributed to J Metz.

At least 181 records · Page 10Linked to original sources
PubMed1980

Normal cellular and humoral immunologic parameters in the baboon (Papio ursinus) compared to human standards.

Normal adult Chacma baboons were investigated with reference to their basic immunological parameters, including serum immunoglobulin concentrations, proportions of T- and B-lymphocytes in the peripheral blood, and lymphocyte response to activators. As rabbit antihuman antisera to immunoglobulins were used for the serum immunoglobulin determinations, cross-reactivity between human and baboon immunoglobulins was evaluated, and it was found that human and baboon IgG and IgM were both completely cross-reactive, while IgA was partially cross-reactive. The serum immunoglobulin concentrations, proportions of T- and B-lymphocytes, and response to activators were found to be similar to those of man. These findings indicate that the Chacma baboon would be a useful and relevant model for the study of cellular and humoral immunology.

Animals↗
PubMed1980

[Cutaneous histiocytosis X].

Histiocytosis X comprises three clinical entities whose common substrate is a localized or systemic proliferation of atypical histiocytes. On the basis of the age of manifestation, acuity of the clinical course and organ involvement Abt-Letterer-Siwe's disease, Hand-Schüller-Christian's disease and eosinophilic granuloma can be differentiated from each other, although transitional varieties of these syndromes are possible. Not infrequently oligosymptomatic forms are misinterpreted, especially when the skin is the only involved organ. In the following case report cutaneous histiocytosis X will be discussed in terms of its clinical expression. Electron-microscopy has proved to be the best methods to make the diagnosis of such atypical cases.

Aged↗
PubMed1979

Characterization of endogenous folate and incorporation of labelled folates into the brain of the South African fruit bat.

Folate in the brain of the South African fruit bat consists of 10-formyltetrahydropteroyglutamic acid and the tri-, tetra- and penta- forms of 5-methyltetrahydropteroylglutamic acid. Following parenteral injection, only 5-[3H]-methyltetrahydropteroylglutamic acid was taken up by the brain, but none of a dose of 14C-labelled tetrahydropteroylglutamic acid was detectable. Only trace smounts of the 5-methyltetrahydropteroylglutamic acid were converted into the formyl compounds and a small amount of methyltetrahydropteroyltriglutamic acid appeared after 96 h. There was no significant difference in vitamin B-12-deficient animals.

Animals↗
PubMed1979

[Naevus spongiosus albus mucosae. Review and personal observations].

White sponge nevus of the mucosa is a rare, mostly verifiable hereditary ectodermal dysplasia of the mucous membranes. Because associated symptoms of the skin are missing, it is classified as a distinctive disease among the congenital leukokeratoses. In the most cases the symptomless mucosal lesions are detected by dentological examination though they are present at birth or appear in the first years of life. On the basis of three own observations clinical appearance, histopathology, electronmicroscopy and differential diagnosis are discussed.

Child↗
PubMed1979

Reformation of gap and tight junctions in regenerating liver after cholestasis.

Morphometric analysis of the alterations in interhepatocyte junctions induced by bile duct ligation revealed that after 48 h, during which time the serum bilirubin increased 6 to 8 fold, the membrane area occupied by gap junctions on the apico-lateral and medio-lateral sides decreased from 3.6% in controls to 0.02% in the ligated group. The strands of the zonulae occludentes were reduced in number and showed increased discontinuities. Within 45 min of recanalization of the common bile duct, clusters of particles appeared within and adjacent to the tight junctional areas or in the lateral hepatocyte membrane. Subsequently, the particle aggregations localized in the apico-lateral membrane areas increased in number and size becoming finally indistinguishable from those of controls within 96 h after the onset of recanalization. The zonulae occludentes also rearranged and reestablished their original structure during this period. The serum bilirubin fell to normal within 24 h of recanalization. It is concluded that metabolic and ultrastructural restitution associated with the recanalization of the ligated bile duct have no strict temporal correlation to one another. These studies provide further evidence that alterations in gap and tight junctions induced by pathological processes, e.g. during bile duct ligation, are completely reversible when regeneration occurs.

Animals↗
PubMed1979

A comparison of methods for the rapid quantitation of unsaturated transcobalamin II and the R-binding proteins.

Methods for the rapid quantitation on unsaturated transcobalamin II (TC II) and R-binders in serum following separation of these binders using a) adsorption by uncoated charcoal, b) adsorption by Quso G32, c) precipitation with ammonium sulphate, and d) acidification of serum, have been compared with the standard gel filtration technique. In serum from healthy subjects and patients with elevated R-binders, the serum acidification and Quso methods yielded results in closest agreement with those obtained by gel filtration. When TC II was markedly elevated, the recommended concentration of Quso failed to remove all TC II from serum. Both the serum acidification and Quso methods are suitable for routine use, providing that with the latter method the concentration of Quso is increased when elevated levels of TC II are anticipated, as, eg, in severe jaundice. All the rapid methods tested yielded clinically significant results in patients with myeloproliferative disorders.

Acids↗
PubMed1979

Intercellular junctions in the full term human placenta. I. Syncytiotrophoblastic layer.

Inter- and intrasyncytiotrophoblastic junctions within the human full term placenta were electronmicroscopically investigated using thin sections and freeze-fracturing. Narrow clefts were occasionally situated between surface areas where adjacent chorionic villi exhibited close contact. Within these clefts, extensive zonulae and maculae occludentes and numerous maculae adherentes were found. The zonulae occludentes showed a continuous and irregular course on the membrane surface, and the maculae occludentes were irregularly distributed over extended membrane areas. Besides these areas, maculae occludentes and maculae adherentes were observed on infoldings and invaginations of the synctiotrophoblastic surface membrane. Investigations of the inner surface of the syncytiotrophoblastic layer, that is, the layer facing the villous stroma, also revealed invaginations joined by maculae adherentes. The functional significance of the inter- and intrasyncytiotrophoblastic junctions is discussed with respect to the differentiation of the trophoblast.

Female↗
PubMed1979

Extrapyramidal side effects and increased serum prolactin following fluoxetine, a new antidepressant.

Fluoxetine (Lilly 110140) is a potent, specific serotonin (5-HT) uptake blocker which is being tested in man for antidepressant activity. One of 9 depressed patients receiving this drug developed a dystonic reaction, parkinsonian rigidity, and increased serum prolactin levels, all signs of decreased dopaminergic activity. Homovanillic acid levels also decreased in the cerebrospinal fluid of this subject. We postulate that fluoxetine, via the increase in 5-HT activity resulting from 5-HT uptake blockade, inhibited both the nigro-striatal and tubero-infundibular dopaminergic neurons. These results provide additional evidence for a linkage between serotonergic and dopaminergic neurons in man.

Adult↗
PubMed1979

Transplacental transport in the rabbit of vitamin B12 bound to human transcobalamin I, II and III.

Transcobalamins I, II and III (TCI, TCII, TCIII) were purified from human serum, saturated with 57Co-vitamin B12 (57Co-B12), and injected into pregnant rabbits. Whole body retention of the 57Co-B12 averaged 91% and was similar for each of the three vitamin B12 binders. A maximum of 62% of the injected 57Co-B12 was found in fetal tissues when the vitamin was injected bound to TCII, but only 6--7% when bound to TCI or TCIII. Thus TCII is responsible for the delivery of vitamin B12 to the fetus.

Animals↗
PubMed1979

Role of serum folate binders in the delivery of folate to tissues and to the fetus.

Specific folate binding protein (FBP) and non-specific binding protein have been prepared from pooled serum from patients in late pregnancy. The two classes of folate binder were labelled with 75Se-selenofolate and injected into non-pregnant and pregnant rabbits. Selenofolate bound to specific FBP was delivered predominantly to the liver, in both pregnant and non-pregnant animals. Fetal tissue took up selenofolate from non-specific FBP only. Specific FBP thus functions to deliver folate to stores and represents a storage pool of folate. The non-specific FBP are responsible for the delivery of folate to the fetus, and probably also to sites of utilization.

Animals↗
PubMed1979

Horseradish peroxidase as a tracer for capillary permeability studies.

The permeability of capillaries was investigated utilizing an in vivo injection of horseradish peroxidase (HRP) and an in situ perfusion of a balanced salt solution containing HRP and lanthanum chloride. In the continuous capillaries of heart and muscle, HRP diffuses mainly through intercellular junctions, while in testicular capillaries, the transport is via micropinocytotic vesicles. The diffusion and micropinocytotic transport of HRP was demonstrated in both directions, i.e. from the capillary lumen to the interstitium and vice versa. Lanthanum can be used as a bidirectional inhibitor of micropinocytosis. The transport of HRP is then almost completely hindered in testicular capillaries. In heart muscle, the effect on HRP transport is not significant, due to second transport pathway, i.e. intercellular cleft passage.

Animals↗
PubMed1979

[Generalized herpes simplex].

This report is about a 58-year-old female patient with generalized herpes simplex virus exanthema. The virus was detected not only in the skin eruptions but also in rinsing liquid from the throat. Its typical feature revealed it to be herpes simplex virus Type I. On the basis of similar cases which have been described in literature, we point out that it is necessary to carry out virological and serological tests in cases of uncertain vesico-pustular or erythema exsudativum multiforme like exanthemas. These exanthemas must be separated from the postherpetic erythema exsudativum multiforme because of the identified virus.

Exanthema↗
PubMed1979

Binding of methylfolate and pteroylglutamic acid by the specific serum folate binder.

The binding sites for methylfolate of the FABP in serum are fully saturated in the physiological state. When the FABP of serum from pregnant subjects is stripped of its endogenous folate, it is capable of binding an average of 549 +/- 12 pg/ml (range 464 to 723) of 14C-methylfolate, compared with 736 +/- 57 pg/ml (range 491 to 1610) of 3H-PGA. When 3H-PGA is added to untreated serum, an average of 258 +/- 6 pg/ml (range 218 to 325) is bound by FABP; this binding represents sites available to PGA but not to methylfolate, as well as sites from which methylfolate is displaced by 3H-PGA. This displacement averages 71 +/- 10 pg/ml (range 9 to 142), the amount which the standard technique for measurement of the UFBC for 3H-PGA overestimates the true UFBC for PGA.

Binding Sites↗
PubMed1978

Normal values for haemoglobin concentration and red cell indices in preschool children on the Highveld.

Data on haemoglobin concentration, red cell count, packed cell volume, mean cell volume, mean cell haemoglobin and mean cell haemoglobin concentration for 'normal' children aged 1-4 years living on the Highveld (altitude 1400-1800 m) are presented in yearly age groups. The children were defined as normal on the basis of having growth attainment and iron, folate and vitamin B12 nutrition within accepted normal limits. The results obtained differ from the standard reference values published for children resident at sea level. It is suggested that the mean (+/- 2 SD) ranges presented be used as normal ranges in the population studied.

Aging↗