Biomedical subjects
M Adam
Publications and source records attributed to M Adam.
Uptake of gold by collagen in gold therapy.
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Delayed hypersensitivity and antibody response in rheumatoid arthritis.
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Reaction of gold with collagen in vivo.
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Quantitative changes in insoluble collagen during ontogeny in rodents (collagen type I and type III).
It has been proved in three rodent species that in the insoluble collagen fraction which accumulates in skin collagen with age of the two categories of collagen present (collagen type I and collagen type III), their proportion alters in favour of collagen type I with the advancing age. Since it has also been shown that collagen type I is less resistant towards proteolytic cleavage than is collagen type III its accumulation can be explained either by rapidly advancing cross-linking of this collagen type or more likely by different proteosynthesis. The second alternative is preferred since a step-wise polymerization of collagen type III was also observed. No information revealing to what extent the lysine derived cross-links can combine both collagen types is at present available. On the basis of this information the rapid decrease in insoluble collagen in very early ontogeny (rats below 8 weeks of age) is explained.
Electron microscopic investigation of the effects of diabetes mellitus on the Achilles tendon.
Fine structural changes in the Achilles tendons of patients with long-term diabetes mellitus were investigated. All patients had clinical and electrophysiological evidence of diabetic neuropathy and had ulceration and/or Charcot neuroarthropathy. Several differences between tendons of diabetic (n = 12) and nondiabetic (n = 5) individuals were observed by electron microscopy. In diabetics, these differences included increased packing density of collagen fibrils, decreases in fibrillar diameter, and abnormal fibril morphology. In one diabetic patient, individual collagen fibrils were tightly apposed so that many areas of tendon appeared as a single mass of closely adhering fibrillae. In addition, foci in which collagen fibrils appeared twisted, curved, overlapping and otherwise highly disorganized were common in specimens from most patients (11 of 12). These morphologic abnormalities in the Achilles tendons of diabetics appear to reflect a poorly known process of structural reorganization that may be the result of nonenzymatic glycation expressed over many years. Such structural changes could contribute to the tightening of the Achilles tendor a phenomenon consistent with clinical observations of extreme shortening of the Achilles tendon-gastrocnemius-soleus complex common in advanced diabetic neuropaths. In patients with diabetic neuropathy, tendon shortening causes severe equinus that may precipitate serious ulceration, stress fractures, and Charcot collapse of the foot. However, in nondiabetics, the fine structure of the Achilles tendon appears normal, consistent with the finding that the ultrastructural changes result from diabetes rather than neuropathy.
The evaluation of hemorrhage in cardiac patients who have undergone extracorporeal circulation.
The present study defines excessive bleeding in patients who undergo cardiopulmonary bypass, and evaluates the use of coagulation testing to predict those patients that bleed excessively. Evaluation of 774 consecutive patients undergoing aortocoronary bypass surgery was carried out. Cardiopulmonary bypass consisted of a bloodless prime and a Harvey bubble oxygenator. In the postoperative period, excessive hemorrhage was defined as that exceeding 600 ml chest tube drainage in the first eight hours. One hundred and sixty-three patients (21%) were noted to be in this category. Excessive bleeding postoperatively was best predicted by a PTT greater than 45 seconds, a PT greater than 19 seconds, a fibrinogen level less than 225 mg/dl and a TFT equal to or less than 1:32. These laboratory findings occur singly or in combination. The assessment of platelet, numbers or function and fibrin(ogen) split products were of no prognostic value. Using these criteria, the re-exploration rate for excessive hemorrhage and/or tamponade was 0.6 per cent (5 out of 774 patients). No preoperative laboratory test of hemostatic function was useful in predicting coagulopathies resulting from cardiopulmonary bypass.
Standardization of immunoassays for antiphospholipid antibodies with beta 2GPI and role of other phospholipid cofactors.
Presence of beta 2 Glycoprotein I (beta 2GPI), in addition to phospholipids, is an absolute requirement for binding APA. This binding is frequently observed with beta 2GPI coated alone, however many APA react only with beta 2GPI complexed to phospholipids, but not with phospholipids alone. We demonstrate that a subgroup of rabbit polyclonal antibodies to human beta 2GPI binds to this protein only when it is coated on a solid surface, but not if it is in solution. In addition, beta 2GPI present in goat serum is strongly fixed by the coated phospholipids and the complexes formed bind as well APA as the rabbit antibodies to beta 2GPI. The diluent used for testing APA, has a strong incidence on APA's reactivity as it can be a source of beta 2GPI. Antibody binding to beta 2GPI, Prothrombin, Protein S, and Annexin V, coated in the presence or in the absence of phospholipids, was tested in 55 patients with the antiphospholipid syndrome. The strongest binding of antibodies was observed in 39 plasma to a mixture of phospholipids and purified human beta 2GPI, however 17 samples also presented a significant reactivity to beta 2GPI alone. Nine plasmas contained antibodies to Prothrombin, 4 to Protein S, 3 to Annexin V, and 1 to Protein C. We conclude that most of the APA are directed to a complex of beta 2GPI and phospholipids although in some patients antibodies to beta 2GPI alone or to other phospholipid binding proteins are present.
Limitations of detection of bone-marrow micrometastasis in prostate carcinoma patients by CK18/PSA immunocytochemistry and PSA RT-PCR.
BACKGROUND: The aim of this study was to prove the reliability of cytokeratin 18/prostate specific antigen (CK18/PSA) immunocytochemistry to detect tumor cells in the bone marrow of patients with prostate cancer (CaP) compared with a control group without CaP. PATIENTS AND METHODS: In bone marrow aspirates of 34 patients with CaP and 11 control patients without CaP, CK18/PSA immunocytochemistry was performed and compared with PSA RT-PCR in bone marrow and blood. RESULTS: 12% of tumors showed a positive staining with PSA and and 17% with CK 18 immunocytochemistry. There was no correlation with the stage or grade of the CaP. False positive results occurred in 2 out of 6 males without CaP and in 2 out of 5 women. 35% of the samples were found to have PSA-mRNA signals in RT-PCR which were neither associated with the histological stage or grade nor the PSA staining in immunocytochemistry. CONCLUSION: False positive staining results were obtained in control patients. Detection of PSA-mRNA was not associated with immunocytochemistry. Neither immunocytochemical nor PCR results were associated with the histological stage of the CaP. Thus, detection of micrometastasis using immunocytochemical methods has to be interpreted with caution and cannot be recommended as a clinical staging procedure.
Rapid determination of total trans fat content--an attenuated total reflection infrared spectroscopy international collaborative study.
Interest in trans fat labeling has prompted efforts to develop new, more efficient methods for rapidly and accurately determining trans fat content of foods. A novel and rapid (5 min) attenuated total reflection-Fourier transform infrared (ATR-FTIR) spectroscopic procedure was recently developed and applied to food products. This procedure was voted official method AOCS Cd 14d-99 by the American Oil Chemists' Society in 1999 after testing in a 12 laboratory international collaborative study. The results of the study are described in this paper. Analytical ATR-FTIR results exhibited high accuracy in the range 5-40% trans; results tended to have <2% high bias relative to the gravimetrically determined values. The precision of this internal reflection method was found to be superior to the precision of transmission infrared official methods. It is recommended that the applicability of the ATR-FTIR method be limited to trans levels of >5% (as percent of total fat).
The role of cartilage minor collagens in inducing arthritis.
Arthritogenic properties of native types IX, XI, and II collagen were investigated in female Wistar rats. Immunization with native type-XI or -II collagen led to the arthritic reaction in 60% of investigated rats. After boosting, a distinct increase in anticollagen antibodies was observed followed by temperature rise (swelling and redness of affected joints). At the end of the experiment (after 7 weeks) subchondral bone destruction was detectable upon x-ray examination. Histological observation of the affected knee and ankle joints showed progressive destruction of the articular cartilage and subchondral bone accompanied by proliferative synovitis with extensive formation of fibrous tissue found in joints of rats immunized with native type-XI collagen. Immune response to collagen types (determined by ELISA) reached its peak between the 14th and the 21st day. From the acute stage to the chronic stage a decrease of serum anticollagen antibodies was observed to remain constant. Rats immunized with native type IX and denatured type XI collagen did not develop arthritis.
Contribution to the mode of action of univalent gold.
Au+ binds to the collagen structure and, therefore, the authors studied the kinetics of the interaction between sodium gold thiosulphate (SGTS) and C1q complement subcomponent, the structure of is partially collagenous. The kinetics was evaluated densitometrically and compared with that of collagen and SGTS. On the basis of those results, the effect of SGTS upon collagen type-II-induced arthritis (CIA) was investigated in Wistar rats. SGTS (20 mg per kg of body weight weekly) was administered i.m. starting i) with the first immunization dose, ii) with the second immunization dose, and iii) after the onset of arthritis. Regardless of the timing of drug administration the manifestation of arthritis was decreased, but the decrease was more expressed in the first two groups. It was concluded that SGTS administration is capable of inhibiting CIA, provided that the drug is applied sufficiently early. Since formation of antibodies to type-II collagen remained unaffected, it is feasible that the mode of action of gold complexes is based mainly on blocking the activation of complement system.
[Test of Materna o milk supplemented with iron in the feeding of premature infants].
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[Optimization of nutrition for premature infants using essential fatty acids].
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Determination of collagen degradation products in human urine in osteoarthrosis.
A new method for profiling human urine has been developed. Peptides of molecular weight greater than 10,000 were separated by high-performance liquid chromatography with fluorescence monitoring (excitation 297 nm, emission filter 389 nm) adjusted for detection of collagen cross-linking compound pyridinoline. The collagen origin of some peptides was confirmed by determination of hydroxyproline in their hydrolysates. Peak heights were substantially higher in patients with osteoarthrosis than at healthy controls. After replacement of the diseased joint by total endoprosthesis the chromatograms changed and were similar to those of healthy controls.
[Mosaic trisomy 18 associated with Jeune syndrome].
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[Immunological aspects of chronic hepatitis in children].
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Serum complement values in healthy and poststreptococcal glomerulonephritis children determined immunochemically and immunohaemolytically.
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