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Biomedical subjects

L Hartmann

Publications and source records attributed to L Hartmann.

At least 109 records · Page 6Linked to original sources
PubMed1980

Effects of in vitro and in vivo exposure to insulin upon glucose carbon accumulation in rat aorta: different patterns of response for intima-media and adventitia.

We have studied the effect of insulin upon the accumulation of glucose carbon into the intima-media and the adventitia of rat aorta following in vitro exposure by adding insulin to the incubation medium, and in vivo exposure by producing relative hyperinsulinemia during life and subsequently incubating excised tissue in a medium containing no insulin. Hyperinsulinemia in vivo was either (1) endogenous--following 1.5-2 hr of refeeding after a 48-hr fast--or (2) exogenous--following an i.v. injection of insulin. For adventitia, a significant stimulation was found after both in vitro (+ 53%, p < 0.001) and in vivo exposure to insulin (+ 96%, p < 0.01 with endogenous insulin; + 75%, p < 0.05 with a dosage of 2 U/kg of exogenous insulin). For intima-media, the stimulation was weak and insignificant after in vitro exposure (+ 11%, p > 0.30), but became important and significant after in vivo exposure to insulin (+ 100%, p < 0.001 with endogenous insulin; + 50%, p < 0.05 with a dosage of 0.5 U/kg and + 49%, p < 0.05 with a dosage of 2 U/kg of exogenous insulin). For the in vivo exposure experiments, we found a significant linear correlation (r = 0.611, p < 0.005) between plasma insulin concentrations and glucose carbon accumulations into intima-medias of control and refed rats. These results establish the insulin sensitivity of the adventitia and show a sensitivity of intima-media only to in vivo insulin exposure. These different behaviors of intima-media in vivo and in vitro may have a hemodynamic basis.

Animals↗
PubMed1980

[Preliminary study of the synthesis, plasma circulation and urinary elimination of melatonin in man and the rat].

A structural immunochemical study has shown that fixation of melatonin on bovine serum albumin by formaldehyde occurs via reaction of both an indole NH group and the side chain, allowing extremely specific antibody production. Isotopic in vitro investigations and radioimmunological estimation of this hormone in man and in the rat shows that it is transported by plasmatic albumin in a 1/10(6) ratio and is eliminated in the urine as native material, 6-hydroxy melatonin and as an as yet unidentified metabolite.

Animals↗
PubMed1979

Double antibody specificity of lymphoid cells isolated from normal human intestinal mucosa.

Lymphoid cells were isolated from normal human mucosal specimens. A certain fraction of these cells exhibited double antibody specificities at the levels of both light kappa and lambda chains and heavy mu and gamma chains. The variable frequency with which these cells were detected appears to be a characteristic of this population. They represent a very low proportion of the total number of cells isolated.

Antibody Specificity↗
PubMed1979

Determination of blood urea by gas-liquid chromatography. A comparison with two other methods.

An original method for the quantitative determination of plasmatic urea by gas-liquid chromatography (GLC) is described. It is based upon the transformation of urea into urethane by alcoholic deamination in a warm and strictly anhydrous medium. Compared with the two other usual methods (enzymatic and colorimetric), the GLC technique is extremely reliable and specific, and can easily be adapted to biological fluids.

Chromatography, Gas↗
PubMed1978

[The molecular expression of C1 esterase inhibitor in hereditary angioneurotic oedema. Study of 32 families (author's transl)].

Seventy seven patients from 32 families suffereing from angioneurotic oedema were studied and a single theory of the disorder is suggested. The functional abnormality of alpha2 neuraminoglycoprotein (NGP) or of C1 esterase inhibitor is related involvement of the structure gene (s) controlling its synthesis. Particular immunochemical characteristics of the inhibitor seen in severals families and remaining constant through a number of generations would indicate the existence of a phenomenon of functional haploidism in these heterozygous patients. Treatment of the condition with androgens suggests the existence of two varieties of alpha2 NGP molecules which are differentiated on the basis of their complete or incomplete glycoconjugation in the hepatocyte.

Androgens↗
PubMed1978

[Study of amino monosaccharides by thermoionic detection in gas-liquid chromatography. Application to a pyroglobulin IgM (author's transl)].

The monosaccharides of proteic samples liberated by methanolysis and submitted to trimethylsilylation by the trimethylsilylimidazole (TSIM) are determined by gas-liquid chromatography. The neutral sugars are detected in simple flame ionization (FID) and the amino sugars identified separatively by the use of a thermoionic detector (TID) which responds selectively to nitrogenous and phosphorated compounds. The method described has been tested on standard mixtures of monosaccharides and on a well known glycoprotein : the uromucoid. Then it has been applied to a pyroglobulin IgM (mu2, chi2).

Amino Sugars↗
PubMed1978

Salivary immunoglobulins in progressive systemic sclerosis.

A study of salivary immunoglobulins revealed the presence of IgM in 11 out of 17 patients suffering from progressive systemic sclerosis. The presence of IgM was frequently accompanied by an increase in IgA and less often by IgG. Immunofluorescence examination of labial biopsies showed comparable modifications in the immunocyte populations; the presence of IgM cells, sometimes in large numbers, and an increase in IgA and IgG cells. All patients with a nodular lymphoplasmocyte infiltration of the minor salivary gland of the lip have salivary IgM. The presence of IgM in the saliva is a diagnostic criteria of Sjögren's syndrome. The absence of a correlation between immunoglobulin concentrations in the saliva and the serum and correlation between the salivary IgM concentration and the number of IgM immunocytes, demonstrate that the presence of IgM is related to the glandular synthesis of this enzyme.

Adult↗
PubMed1978

The gene(s) controlling the synthesis of C1 esterase inhibitor is not linked to the genes of the HLA system and is not on the 6th chromosome.

Certain genes of the complement system are carried by the 6th chromosome and are sometimes linked to particular genes of the HLA system. This study shows that in 15 patients suffering from hereditary angioneurotic oedema the gene(s) controlling the synthesis of C1 esterase inhibitor is not linked to the genes HLA-A or B and is not on the 6th chromosome.

Angioedema↗
PubMed1978

Human lymphoid cells of the intestinal mucosa showing specificity for both immunoglobulin light and heavy chains.

The presence of single human lymphoid cells expressing on the one hand both kappa and lambda light chain and on the other hand either both mu and alpha or both mu and gamma heavy chains, was observed in the intestinal mucosa. The variability of the frequency of such cells, both from one subject to another, or in the same sample, is a characteristic of this population.

Humans↗
PubMed1977

[Abdominal manifestations in hereditary acute angioneurotic oedema. Value of study of the complement system (author's transl)].

Four individuals of the same family suffered from a functional deficiency in C1 esterase inhibitor. In three of them, the manifestations of hereditary angioneurotic oedema were abdominal, paroxystic and pseudo-surgical. They were related to the development of visceral or mucosal oedema. The measurement of total complement (and of its fractions) during the acute episode, as well as dynamic complement studies between attacks, represent a simple method for indicating the probable diagnosis. Only estimation of the functional activity of C1 esterase inhibitor provides definite evidence. Familiarity with the clinical and biological characteristics of these acute abdominal episodes makes it possible to avoid repeated, unnecessary operations in these patients. They should be treated medically, under surgical surveillance, since a patient with angioneurotic oedema may have nevertheless a specific lesion, in addition. In addition, the episode may spread at any time, resulting in oedema of the glottis requiring tracheotomy or immediate intubation.

Abdomen, Acute↗
PubMed1977

[Lymphoid cells of the intestinal mucosa with double kappa and lambda specificity in normal man].

The presence of lymphoid cells possessing both kappa and lambda specificities has been observed in the intestinal mucosa of normal subjects. The variability in the number of such cells in different sections of the same sample and in different subjects seems to be a characteristic of this cell population and may reflect the high activity of the immune system in the small intestine.

Fluorescent Antibody Technique↗
PubMed1977

Diagnostic and therapeutic problems associated with hereditary deficiency of the C1 esterase inhibitor.

Six patients in a family with a history of hereditary angioedema reported swelling of the extremities and recurrent abdominal pain occurring spontaneously or after trauma. Attacks of oedema involving the airways, the greatest danger with this disorder, were present only in one case. This autosomal dominant disease is due to deficient activity of the inhibitor of the first component of complement. Low levels of C4, and absence of C1 esterase inhibitor confirm the diagnosis. Two asymptomatic cases with the appropriate biochemical abnormality are reported in this study. For short term prophylaxis of attacks (before surgery expecially), fresh frozen plasma is used, or better still, C1 esterase inhibitor. For long term prophylaxis of attacks antifibrinolytic and hormonal drugs are used: in two cases, the authors obtained good results with methyltestosterone after failure of tranexamic acid.

Adult↗
PubMed1977

An investigation of the complement system in patients with periodic disease (results from 29 cases).

The complement system was investigated in 29 patients suffering from authentic periodic disease. A statistically significant increase in C4, also in total complement and C3 could be demonstrated. It is possible that the increase in C4 was due to the macrophages which are always present in the infiltrates of periodic disease. This biological observation is of clear practical importance for the diagnosis of the condition both before and after colchicine therapy.

Complement C1 Inactivator Proteins↗
PubMed1977

Immunochemical study on serum proteins in systemic sclerosis.

Forty one patients with systemic sclerosis were studied after separation into three groups according to Barnett's classification. A multi-dimensional statistical analysis eight serum proteins revealed a difference between control patients and patients with type I and type II scleroderma. Type I scleroderma was characterised by a rise in alpha 2 macroglobulin and in the C4 fraction of complement, whilst in type II scleroderma all the proteins studied were raised, with the exception of CO complement, which was normal, and transferrin which was markedly decreased.

Blood Proteins↗