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Biomedical subjects

G Lang

Publications and source records attributed to G Lang.

At least 37 records · Page 2Linked to original sources

[In Process Citation]

Since 1996 thoracic surgery has been invoiced according to fixed reimbursement rates (Sonderentgelte, SE). The legislator argues that fixed reimbursement rates cover operation costs and justify a 20% reduction in reimbursement for nursing. In order to examine this assumption we performed a cost analysis of thoracic surgery. Taking into account the staff, equipment, and operating theatre supplies, we analyzed 30 cases of five different types of operation prospectivly: wedge resections with more than three wedges (AR: n = 8), lobectomies (LE: n = 8), pneumonectomies (PE: n = 5), thoracoscopic wedge resections (VR: n = 6) and resections of mediastinal tumors (MR: n = 3). Then we calculated the overall costs for each operation. The costs for a LE amounted to DM 9,927, which is DM 4,904 more than the corresponding fixed reimbursement rate. The costs were DM 11,562 for a PE, DM 12,477 for a VR and DM 7,532 for a MR. Thus the costs were DM 5,539, DM 2,435 or DM 1,907 higher than the corresponding fixed reimbursement rates. The fixed reimbursement rate for an AR was DM 866 higher than the actual cost of DM 6,922. Only for a small number of cases do the fixed reimbursement rates cover the actual costs of thoracic surgery. Thus operation costs still need to be at least partly covered by the reimbursement for nursing.

Journal Article↗

Cloning and functional expression of the D-beta-hydroxybutyrate dehydrogenase gene of Rhodobacter sp. DSMZ 12077.

Nucleotide sequence and biochemical analysis of D-beta-hydroxybutyrate dehydrogenase (EC 1.1.1.30), isolated from Rhodobacter sp., indicate functional oligomers composed of subunits of 257 amino acids with a calculated M(r) of 26,800 and a pI of 5.90. Compared to mammalian short-chain alcohol dehydrogenases, the bacterial enzyme lacks a C-terminal lipid anchor domain and was found to be highly active upon expression in Escherichia coli even without lipid supplement. The recombinant enzyme could be highly enriched using a single chromatography step and was shown to be stable over a broad range of pH and temperature.

Animals↗

[Clinical presentation and coronary angiographic results in unstable angina pectoris].

The syndrome "unstable angina" (UA) covers a broad spectrum of patients. In this study we tried to determine the relationship between the severity of UA and angiographic findings. We evaluated 1000 consecutive patients undergoing coronary angiography. Those with the clinical diagnosis "UA" were included in the study. In a retrospective analysis of their records we categorized them, using the Braunwald-classification for determination of the severity of the disease. 352 patients were include, 209 men and 143 women, the mean age was 65 years. 47% met Braunwald-Class I, 26% Class II and 27% Class III. Coronary single-vessel disease was present in 29%, two-vessel disease in 20%, three-vessel disease in 25%, normal coronaries in 13% and coronary atherosclerosis without critical narrowing in 13%. Left ventricular function was preserved in 72%, mild systolic dysfunction was found in 10%, moderate in 13% and severe in 5%. There was no overall correlation between clinical presentation (Braunwald-Classes) and angiographic findings. Women showed a similar distribution of Braunwald-Classes, but significantly more coronary arteries without critical obstruction. In patients with reduced systolic function the percentage of multi-vessel disease was significantly higher, the percentage without relevant coronary artery narrowing was significantly lower. 1) The lack of overall correlation between clinical presentation and angiographic findings supports the importance of coronary angiography in the evaluation of patients with UA. 2) The assessment of women with chest pain is more difficult than of men with regard to coronary heart disease. 3) UA in patients with impaired left ventricular function is a predictor of severe coronary artery disease.

Aged↗

Structure-function relationships of mitochondrial monoamine oxidase A and B: chimaeric enzymes and site-directed mutagenesis studies.

To gain insight into the structure of monoamine oxidases (MAO) A and B, we investigated the properties of various chimaeric enzymes, engineered by moving progressively the junction between the NH2- and the COOH-termini of each MAO form. Whereas exchange of the ADP-binding sequence did not modify the catalytic properties of either MAO isoforms, chimaeras with increasing length of the NH2-terminus of MAO-A (up to position 256) showed a marked decrease in affinity towards substrates and inhibitors. Two sequences, spanning position 62 to 103 and 146 to 220, appeared of particular importance in putatively constituting the binding site of MAO-B. Conversely, the catalytic properties and specificity of MAO-A were insensitive to substitution of both the NH2-(up to position 112) and COOH-termini (from residue 395), but further modification of the central sequence of MAO-A was not compatible with activity. None of the engineered chimaeras showed a shift in substrate and inhibitor specificity. Investigation on MAO-B by site-directed mutagenesis revealed that His382 and Thr158 may represent residues relevant for MAO-B catalytic mechanism.

Amino Acid Substitution↗

Effects of pravastatin on cholesterol metabolism of cholesterol-fed heterozygous WHHL rabbits.

1. We administered the 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitor pravastatin at a daily dose of 1 mg kg(-1) body weight to cholesterol-fed (0.03%) heterozygous Watanabe heritable hyperlipidaemic rabbits, an animal model for heterozygous familial hypercholesterolaemia. 2. After 12 months of cholesterol treatment, immunohistochemistry with the monoclonal antibody 9D9 was used to detect hepatic low density lipoprotein (LDL) receptors, which were quantified by densitometry. In addition we determined LDL receptor mRNA by competitive reverse transcriptase polymerase chain reaction. The cholesterol precursor lathosterol and the plant sterol campesterol were analysed by gas-liquid chromatography. 3. The drug reduced total plasma cholesterol levels by 51% (P=0.04), when compared to the control group. Unexpectedly, hepatic LDL receptor density and mRNA showed no significant differences between the groups. Total plasma levels of lathosterol and campesterol also revealed no significant differences between the groups, if expressed relative to plasma cholesterol. 4. The findings suggest that mechanisms other than induced hepatic LDL receptors are responsible for the cholesterol-lowering effect of pravastatin in this animal model. We propose a reduced cholesterol absorption efficiency compatible with similar campesterol levels between both groups observed in our study.

Animals↗

Comparison of virtual and fiberoptic bronchoscopy.

Preoperative diagnostic procedures in the treatment of non-small-cell lung carcinoma (NSCLC) include fiberbronchoscopy (FBS) and CT scanning of the thorax and abdomen. The introduction of double-detector helical computed tomography has led to improved image resolution which allows three-dimensional reconstruction of the bronchial tree. A special computer simulation provides a virtual endoscopic view into the inner surface of the bronchial system. In order to determine whether the so-called virtual bronchoscopy (VBS) accurately reflects the anatomic situation of the bronchial tree, neoplastic lesion, and postoperative control of sleeve resections, we performed a virtual bronchoscopy in 24 patients with NSCLC and in 6 patients following sleeve resections and compared the results with the findings of fiberoptic bronchoscopy. An anatomic computer simulation of the bronchial tree was created in 100% of the investigated patients. Central tumor stenosis or occlusion was visualized by VBS as well as by FBS. In peripheral tumorous lesions VBS revealed the correct diagnosis in only 75%. VBS, however, enables viewing beyond the stenosis. FBS remains the gold standard in the endoscopic diagnostic procedures, showing not only airway patency but also mucosal changes in the vicinity of the tumorous lesion. VBS, however, gives further information about the poststenotic area in occlusive main bronchus stenosis. Furthermore, adequate control investigation of airway patency in patients following sleeve resections or stent implantation can be performed by VBS.

Bronchoscopy↗

Neuromagnetic recordings of the human peripheral nerve with planar SQUID gradiometers.

Magnetic fields produced by a travelling volley in the human ulnar nerve have been successfully measured in a lightly shielded environment. Recordings of the tangential component of the magnetic field were made using a planar second-order gradiometer integrated with a first-order gradiometric superconducting quantum interference device (SQUID). Devices were fabricated in our clean-room facility at the University of Strathclyde and measurements taken in an eddy-current shielded room at the Wellcome Biomagnetism Unit. We use no additional shielding and no electronic differencing or field-nulling techniques. Evoked magnetic fields of 60 fT peak-to-peak were obtained after 1536 averages but they could be seen easily as early as 512 averages. Measurements were made over four points above the ulnar nerve on the upper arm and from these the conduction velocity was calculated as 60 m s(-1).

Equipment Design↗

Comparison of remifentanil in combination with isoflurane or propofol for short-stay surgical procedures.

There are few data in the literature that describe the use of remifentanil when administered as a component of an inhalation or total i.v. anaesthetic (TIVA) technique. We studied 251 male and female patients, aged 18-75 years, ASA I-II, undergoing inguinal hernia repair, arthroscopic knee surgery or varicose vein surgery of at least 30 min duration without premedication. Patients were randomized to receive a remifentanil loading dose of 1.0 microgram kg-1 followed by a continuous infusion of 0.5 microgram kg-1 min-1 in combination with isoflurane (end-tidal concentration 0.6%), (Group I, n = 115) or propofol (initial infusion rate 9 mg kg-1 h-1 reduced to 6 mg kg-1 h-1 after 10 min), (Group P, n = 118). The remifentanil infusion rate was reduced by 50%, 5 min after tracheal intubation. Intraoperative stresses were treated with a remifentanil bolus (1 microgram kg-1) followed by an increase in the remifentanil infusion rate. At the insertion of the last suture, the remifentanil infusion and concomitant anaesthetic were switched off simultaneously. Times to spontaneous respiration, adequate respiration and tracheal extubation were significantly shorter in group I compared with group P (6.4 min vs 7.6 min, P < 0.01; 7.6 min vs 9.3, P < 0.003; 7.8 min vs 9.5 min, P < 0.015). Overall mean systolic blood pressures during surgery were greater in group P compared with group I (P < 0.05) but the absolute differences were clinically insignificant (4-5 mm Hg).

Adolescent↗

Comparison of real-time virtual and fiberoptic bronchoscopy in patients with bronchial carcinoma: opportunities and limitations.

OBJECTIVE: Both helical CT and fiberoptic bronchoscopy are used in the staging of pulmonary tumors for therapeutic decision making. The improved resolution offered by helical CT has led to the clinical use of three-dimensional reconstruction techniques such as virtual bronchoscopy. We tested this new simulated endoscopic view of inner organ surfaces and compared it with corresponding fiberoptic examinations of the tracheobronchial system. SUBJECTS AND METHODS: Twenty patients with malignancies of the lung and mediastinum were examined with both virtual bronchoscopy and fiberoptic bronchoscopy. Both examinations were reviewed by radiologists and surgeons familiar with fiberoptic bronchoscopy. Virtual bronchoscopy was calculated and reconstructed from the cross-sectional images on a separate workstation. Stenoses and tumor infiltration were classified from the fiberoptic examination. These results were compared with the virtual bronchoscopy findings. RESULTS: Virtual bronchoscopy of diagnostic quality was achieved in 19 of 20 patients. High-grade stenoses were revealed equally well with virtual and fiberoptic techniques. Virtual bronchoscopy offered the advantage of being able to visualize areas beyond even high-grade stenoses. However, on virtual bronchoscopy discrete infiltration or extraluminal impression was not visible in five patients. In another patient, strong heart pulsation produced motion artifacts that prevented evaluation of the reconstruction. CONCLUSION: Virtual bronchoscopy represents a new noninvasive method for evaluating helical CT findings. In comparison with fiberoptic bronchoscopy, virtual bronchoscopy offers the advantage of being able to visualize areas beyond even high-grade stenoses. In addition to the limited view of fiberoptic bronchoscopy, extraluminal causes of lumen compressions can be analyzed in the cross-sectional images and evaluated together with the virtual representation. However, it was not possible to detect small infiltrations with virtual bronchoscopy. This new representation of helical CT data might be helpful for postoperative follow-up examinations, such as after stent implantation, and can be carried out without additional risk to the patient. Radiologists do need special fiberoptic bronchoscopy knowledge and experience with three-dimensional-reconstructions to differentiate between real stenoses and artificial stenoses that might be caused by pulsation artifacts.

Artifacts↗

Ultrasound guided compression therapy in 134 patients with iatrogenic pseudo-aneurysms: advantage of routine duplex ultrasound control of the puncture site following transfemoral catheterization.

BACKGROUND: The following study was designed to evaluate the effectiveness and safety of ultrasound guided compression therapy (UGCT) of iatrogenic postcatheterization pseudo-aneurysms (PA) on the one hand and to justify the usefulness of the routine colour duplex control of the puncture site following transfemoral catheterization, on the other hand. MATERIAL AND METHODS: During the study period 142 patients with (PA) following transfemoral catheterization were identified by means of colour duplex examination Eighty of these 142 patients were identified during a routine colour duplex control of the puncture site the day after PTA/angiography because of peripheral arterial occlusive disease (PAOD) [group A]; the remaining 62 patients with symptomatic groins were referred from other departments [group B]. RESULTS: In 8 patients of group B UGCT was considered to be contra-indicated, they were primarily treated by surgical repair of the PA. A total of 134 patients (group A 80 patients, group B 54 patients) underwent an UGCT. In total the success rate of UGCT was in group A 100% and in group B 78%. 12/54 patients (all group B) with failure of UGCT underwent a secondary surgical repair of the PA. Within group B there was a negative correlation between delay of diagnosis/UGCT and success (p < 0.04), whereas the size of the sheath did not influence the outcome of the UGCT (p = 0.3). CONCLUSION: Our study confirms the effectiveness and safety of UGCT. Routine colour duplex control of the puncture site the day following the removal of the sheath after percutaneous catheterization and UGCT of PAs without delay can increase the success rate of UGCT and minimize the need for surgical repair of PAs.

Adult↗

[Atypical aortic coarctations in type I neurofibromatosis].

From 1971 through 1996, 16 patients were operated on for atypical aortic coarctation. Three of them (two women, 18 and 27 years old, one boy, 13 years old) had typical signs of neurofibromatosis type I (NF1). All had renovascular hypertension due to suprarenal and/or interrenal aortic stenosis. Two had additional bilateral renal artery stenoses, one with a poststenotic aneurysm. In all patients a thoraco-abdominal aorto-aortic bypass was implanted. The renal artery stenoses were bridged by two aorto-renal, a prothesio-renal, and a spleno-renal bypass. Only one kidney had to be explanted 13 years after revascularization for a recurring hilar aneurysm after ex-situ reconstruction was found to be impossible. At their last follow-up examination (at 16, 14, and 9 years) all patients were normotensive without medication and had normal serum-creatinine measurements. Angiography or spiral-CT done in all patients showed normal function of all bypasses. In literature we found another 27 patients with neurofibromatosis operated on for atypical aortic coarctation. In these young and otherwise healthy patients, even complex reconstructions can be performed with a low rate of complications and excellent long-term results. Surgical therapy of all relevant stenoses (at best in a single procedure) is necessary for complete relief of renovascular hypertension. Consequent follow-up is advised for the detection of possible late complications, especially after exclusion of aneurysms.

Adolescent↗

Isolation and expression of a cDNA clone encoding human kynureninase.

Kynureninase (L-kynurenine hydrolase), a pyridoxal-5'-phosphate-(pyridoxal-P)-dependent enzyme, catalyses the cleavage of L-kynurenine and L-3-hydroxykynurenine into anthranilic and 3-hydroxyanthranilic acids, respectively. In this report, we describe the isolation of a cDNA clone encoding human kynureninase. Degenerate oligonucleotides designed from the amino acid sequences of peptides from rat liver kynureninase, were used as primers for reverse-transcription PCR of rat kidney RNA. The resulting rat cDNA product was then used to screen a human hepatoma cell line (Hep G2) cDNA library. Analysis of a positive cDNA clone showed the presence of an insert of 1651 nucleotides containing an open reading frame coding for a protein of 456 amino acids (theoretical molecular mass = 52357 Da). The predicted amino acid sequence of human kynureninase displayed high similarity to that reported for the rat enzyme and to a Saccharomyces cerevisiae gene product putatively ascribed to kynureninase. Profile analysis of kynureninase primary structure indicated the presence of a pyridoxal-P-binding site consensus sequence assigned to class-V aminotransferases, with Lys276 being the residue binding the cofactor. RNA blot analysis of human tissues, including brain, showed the presence of an approximately 2.0-kb mRNA species in all tissues tested. A second mRNA species (approximately 2.6 kb) was also detected in some tissues. After transfection of HEK-293 cells with the cDNA coding for kynureninase, the K(m) values of L-kynurenine and DL-3-hydroxykynurenine for the recombinant enzyme were 671 +/- 37 microM and 13.2 +/- 2.0 microM, respectively.

Amino Acid Sequence↗

Investigation on the structure of the active site of monoamine oxidase-B by affinity labeling with the selective inhibitor lazabemide and by site-directed mutagenesis.

The structural features of the active site of human monoamine oxidase B (MAO-B) were investigated by affinity labeling and site-directed mutagenesis. The pseudosubstrate inhibitor N-[2-aminoethyl]-5-chloro-2-pyridine carboxamide HCl (lazabemide) can be irreversibly linked to MAO-B by reduction of the enzyme-inhibitor complex with NaBH(3)CN. Analysis of the flavin spectrum of [(3)H]lazabemide-labeled human MAO-B indicated that insertion of the inhibitor did not occur into the isoalloxazine ring of FAD. After trypsin digestion and HPLC peptide mapping of the radiolabeled enzyme, two labeled peptides were observed. Sequence analysis showed that both peptides started at Val371 of human MAO-B. These results indicate that [(3)H]lazabemide is incorporated into the MAO-B peptide stretch containing the FAD-modified Cys397. The function of putative active-site residues contained in this region was investigated by site-directed mutagenesis and expression of the mutant proteins in HEK-293 cells. Substitution of His382 of MAO-B with an Arg greatly reduced the enzymic activity, suggesting that this residue may represent a nucleophile relevant for the MAO-B catalytic mechanism. Whereas it has been shown that mutation of Cys389 with a Ser residue does not markedly affect the activity of the enzyme [Wu, H.-F., Chen, K. and Shih, J.C. (1993) Mol. Pharmacol. 43, 888-893] the mutant carrying an Ala at this position was virtually inactive. Conversely, substitution of Lys386 (to Met) and Ser394 (to Ala) did not markedly modify the kinetic properties of the enzyme. We also report that mutation of MAO-B Thr158 (to Ala) resulted in a dramatic loss of enzymic activity.

Affinity Labels↗

Epithelioid sarcoma of the spine: a case report.

STUDY DESIGN: This case report illustrates a patient presenting with sciatica and diagnosed with epithelioid sarcoma involving the spine. OBJECTIVES: The treatment of this patient involved multiple mass resections and decompressions of the spinal canal. Radio- and chemotherapy were applied once a clear diagnosis was obtained. SUMMARY OF BACKGROUND DATA: Epithelioid sarcoma is a rare tumor mainly arising in the extremities. Confusion with a benign inflammatory process are possible. Treatment after histologic diagnosis involves wide resection. To our knowledge, this report represents the first case of epithelioid sarcoma involving the spine. METHODS: After initial discectomy, recurrent scarring and mass formation required multiple decompression procedures and fusion. The initial pathology revealed inflammatory reaction on fibrosis. In a later procedure, the histologic diagnosis of epithelioid sarcoma was made. Radiotherapy and chemotherapy were begun immediately. RESULTS: Despite aggressive resections, radiotherapy, and chemotherapy, the patient died 3 months after the last surgical procedure. CONCLUSION: Spinal epithelioid sarcoma can be mistaken for a benign inflammatory process. After a histologic diagnosis, aggressive wide resection is necessary. Multiple recurrences are documented with this tumor in other sites. Prognosis in trunk involvement is less favorable than involvement of the extremities. The role of adjuvant radio- and chemotherapy is unclear for spinal involvement.

Adult↗

Characterisation and optimisation of an immunoprobe for triazines.

The characterisation and optimisation of an optical immunoassay with label free detection based on Reflectometric Interference Spectroscopy (RIfS) is presented. The immunoprobe is operated in a sequential scheme, where Fab-fragments react with analyte molecules in a first step. In a second step the optical transducer is used to quantify the amount of unoccupied Fab- fragments in the reaction mixture binding to the hapten-modified transducer surface. For optimisation of the test, the Fab-fragment concentration was varied between 2x10(-8) mol/l and 2.5x 10(-9) mol/l. Down to a concentration of 5x10(-9) mol/l a reduction in the limit of detection has been observed. At the lowest concentration investigated no further improvement has been found due to a reduced binding of the analyte and a strong decrease of antibody binding at the transducer surface. This finding could be explained by the thermodynamics of the antigen-antibody reaction and the performance of the optical transducer used. The limit of detection obtained is discussed with respect to thermodynamics, transducer characteristics and immunoprobe test format.

Journal Article↗

Sensory thresholds and neurophysiological correlates of human perceptual learning.

The repeated presentation of visual targets yields significant improvements of psychophysical thresholds, and in the present paper corresponding alterations in neurophysiological activity of the human brain are reported. A group of 23 healthy adults was investigated in a psychophysical experiment in which hyperacuity thresholds were determined repeatedly for up to about 25 min with vertically and horizontally oriented targets. Evoked brain activity was recorded during the same experimental session from 30 electrodes over the occipital brain areas. For each subject mean potentials were computed offline for two conditions corresponding to "before learning' (i.e. the first half of the experiment) and "after learning' (i.e. the second half of the experiment), and visual evoked brain activity was compared between these conditions. In the psychophysical experiments vernier thresholds decreased significantly with time, and this improvement in performance could be confirmed in a control session after an interval of 9 weeks. All changes in discrimination performance were specifically bound to stimulus orientation. Learning effects were also observed in electrical brain activity, which displayed significantly smaller component latencies and larger amplitudes as a function of training time. In addition, learning affected the topography of the evoked potential fields suggesting that cortical neurons are activated in a different way before and after perceptual learning.

Adolescent↗

Use of a retroviral vector with an internal opsin promoter to direct gene expression to retinal photoreceptor cells.

PURPOSE: Viral-mediated gene transfer to retina, as well as to other tissues, is evolving rapidly. We have evaluated the potential of a retroviral vector with an internal opsin promoter fragment to direct gene expression to retinal photoreceptor cells. METHODS: Two recombinant retroviral vectors were prepared; in each Vector, a 1.4 kb fragment of the mouse opsin promoter was placed downstream from the neoR gene in the Moloney murine leukemia virus-based vector G1Na. The opsin promoter fragment was linked either to the cDNA for mouse rod photoreceptor phosphodiesterase (PDE) beta-subunit or to the bacterial lacZ reporter gene. These vectors were tested for their ability to direct gene expression after transduction of 3T3 and Y79 cells, or of dissociated retinal cell cultures or retinal explants from neonatal mice. RESULTS: As expected, PDE beta-subunit and beta-galactosidase mRNAs were expressed only at low levels in 3T3 fibroblasts and Y79 retinoblastoma cells. Northern blot analysis indicated that expression was derived from the viral long terminal repeat (LTR) promoter. Infection of primary retinal cell cultures or explants from neonatal mice with BAG retrovirus, in which beta-galactosidase is driven by the viral LTR, resulted in expression in many cell types, while the opsin-lacZ vector mediated the expression of the lacZ reporter gene specifically in photoreceptor cells. CONCLUSIONS: The internal opsin promoter fragment appears capable of selectively directing gene expression to photoreceptor cells after retroviral-mediated gene transfer. These findings serve as a basis for future studies using the opsin promoter-beta PDE retroviral vector to rescue photoreceptor cells in the rd mutant mouse, in which the beta-PDE gene is mutated resulting in degeneration of photoreceptor cells during the early postnatal period.

3T3 Cells↗

[Serum concentrations of the MCA tumor marker during pregnancy].

MCA (Mucin like carcinoma associated antigen) is used as a marker for the follow-up control of breast cancer patients, and high levels of MCA have been observed during the course of pregnancy. The aim of our study was to determine the value of MCA as a tumor marker in the follow-up of young breast cancer patients with subsequent pregnancy. We determined the MCA concentration in the sera of 201 pregnant women in the course of gravidity in order to find the degree and time of increase MCA shows during normal pregnancy. 121 serum samples of healthy, non-pregnant women were analysed for MCA in comparison. Up to the 19th week of gestation, the concentration of MCA did not show any differences in comparison to non-pregnant healthy women (n = 121, median: 7 U/ml: 25% percentile: 7 U/ml: 75% percentile: 10 U/ml (control collective). Median: 6 U/ml: 25% percentile: 5 U/ml: 75% percentile: 10 U/ml (gestational week 5-19)). After the 23rd week of gestation, the MCA concentration was elevated. After the 35th week of gestation, all women had MCA levels which were significantly higher than in healthy, non-pregnant women. Median: 100 U/ml: 25% percentile: 71 U/ml: 75% percentile: 147 U/ml (gestational week 36-42). Therefore the tumor marker MCA can be used in the followup of breast cancer only until the 19th week of gestation. After the 23rd gestational week very high MCA concentrations are observed in some cases and can not be distinguished from MCA augmentation due to advanced breast cancer.

Antigens, Neoplasm↗