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Biomedical subjects

F G Lehmann

Publications and source records attributed to F G Lehmann.

At least 19 recordsLinked to original sources

Fecal intestinal alkaline phosphatase: a parameter for toxic damage of the small intestinal mucosa.

An immunoprecipitation procedure is presented for the measurement of rat intestinal alkaline phosphatase (I-AP) in feces. Controls exhibit a logarithmic normal distribution of fecal I-AP. Single administration of an agent toxic for small intestinal mucosa like bleomycin or triparanol induces an increase of fecal I-AP on the 1st day and a marked reduction of I-AP activity on the following 3 days. After the 5th day, abnormal high fecal I-AP activities were observed during regeneration. In parallel, morphometry and measurements of I-AP activity in the homogenate of small intestinal mucosa were performed. Rat fecal I-AP excretion proved to be a simple, non-invasive, sensitive marker for toxic damage of the small intestinal mucosa.

Alkaline Phosphatase↗

Human fetal bone alkaline phosphatase: preliminary immunologic studies.

A partially purified human fetal bone alkaline phosphatase preparation (B-APf) exhibits a class of antigenic determinants not found on any adult bone or liver isoenzymes as well as a set of determinants which it shares with adult bone and liver. The evidence for this is the quantitative immunotitration data which demonstrate the expected precipitation of L-AP, B-APa, B-APf and K-AP by the anti-B-APf reagent at equivalence. However, at high antibody excess, I-AP and P-AP are also precipitated. Conversely, by employing an immunosorbent column of Sepharose-purified L-AP, one can remove the component carrying the antigenic determinants shared with L-AP, B-APa and K-AP. Remaining in solution are antibodies which recognize determinant(s) shared by B-APf, P-AP and I-AP.

Adult↗

Peptide hormones in liver cirrhosis and hepatocellular carcinoma.

Immunoreactive serum levels of human chorionic gonadotrophin (HCG), its alpha- and beta- subunits (alpha-HCG and beta-HCG), calcitonin (CT), parathyroid hormone (PTH), prolactin (PRL), adrenocorticotropic hormone (ACTH), and growth hormone (GH) were increased in 8 to 68% of 44 patients with hepatocellular carcinoma. With the exception of two patients, ACTH and PRL levels were only moderately increased, while alpha-HCG, GH, ACTH and PRL levels were not significantly different from the levels found in cirrhosis suggesting that metabolic effects due to impaired liver function may be responsible for their increase in liver cirrhosis and primary liver cell carcinoma. In contrast, HCG, beta-HCG, CT and PTH were associated with a higher incidence of elevated immunoreactive hormone levels than the other peptide hormones; higher concentrations were noted in tumor patients than with liver cirrhosis alone. Therefore, we suggest that metabolic effects due to cirrhosis may influence the serum levels and be more important than ectopic secretion by hepatocellular carcinoma.

Adrenocorticotropic Hormone↗

Human alkaline phosphatases. Evidence of three isoenzymes (placental, intestinal and liver-bone-kidney-type) by lectin-binding affinity and immunological specificity.

The structural relationship between human alkaline phosphatase isoenzymes from placenta, intestine, liver, bone and kidney was investigated by lectin-binding affinity chromatography. In addition, antibody-binding sites of the enzymes were studied using monospecific antisera against each of the isoenzymes. Evidence is offered for the existence of three classes of alkaline phosphatases: the placental isoenzyme, the intestinal isoenzyme and the liver-bone-kidney-type-isoenzyme: 1. A high affinity to bind to concanavalin A and lentil lectin characterizes the placental isoenzyme in contrast to the other isoenzymes. The intestinal isoenzyme remains totally unbound. The liver-bone-kidney-isoenzyme demonstrates a microheterogeneity with bound and unbound parts. A small unbound fraction can be detected in the placental isoenzyme, also when lentil lectin is used. 2. The placental isoenzyme and the isoenzymes purified from liver, bone and kidney are bound by wheat germ lectin-Sepharose, but not the intestinal isoenzyme. All isoenzymes are eluted as a homogeneous peak. 3. Using Helix pomatia lectin-Sepharose, all isoenzymes are unreactive except a minor fraction of kidney alkaline phosphatase. 4. Antibodies to the placental isoenzyme show a partial cross-reaction with the intestinal isoenzyme, but can be obtained monospecific after absorption. 5. Antibodies to the intestinal isoenzyme show a partial cross-reaction to the placental isoenzyme, respectively, but are monospecific again after absorption. 6. Antibodies to liver, bone or kidney isoenzymes show a complete cross-reaction, but are unreactive with the placental and intestinal isoenzyme; after absorption with a heterologous isoenzyme of this group, no further reaction can be demonstrated with any of the three isoenzymes. Thus, lectin-binding affinity identifies the same isoenzyme classes by their carbohydrate parts, as antibodies presumably do by the protein parts of the isoenzymes. Furthermore, lectin-binding affinity demonstrates a microheterogeneity of the placental isoenzyme with lentil lectin-Sepharose and of the liver-bone-kidney-type-isoenzyme with different lectins.

Alkaline Phosphatase↗

Differentiation of human alkaline phosphatases by lectin binding affinity.

Purified human alkaline phosphatases were separated by lectin binding affinity to Wheat germ lectin-Sepharose, Concanavalin A-Sepharose and Lentil lectin-Sepharose into three isoenzymes: the placental, the intestinal and the liver-bone-kidney-type isoenzyme. Therefore, the carbohydrate chains of purified human alkaline phosphatases demonstrate the same isoenzyme classes than studies on structural, catalytical or immunological properties. The liver-bone-kidney-type isoenzyme shows a not yet described microheterogeneity on Concanavalin A and Lentil lectin. Thus, lectin binding affinity is a useful tool for the purification and separation of human alkaline phosphatase.

Alkaline Phosphatase↗

Intestinal alkaline phosphatase: an immunoprecipitation method for the determination in feces.

An immunoprecipitation method for the determination of human intestinal alkaline phosphatase (I-AP) in feces is described using anti-human I-AP IgG. Antibodies to human I-AP are monospecific after absorption with human placental alkaline phosphatase and show no cross-reactions with human liver alkaline phosphatase or alkaline phosphatase from E. coli. Normal controls demonstrate a logarithmic normal distribution of I-AP activity in feces. The standard deviation of the intra- as well as of the inter-assay variation is 11.7%. This method represents a simple quantitative non-invasive in vivo assay for brush border damage under experimental and/or clinical conditions.

Alkaline Phosphatase↗

Damage of rat small intestine induced by ethanol. Effect of ethanol on fecal excretion of intestinal alkaline phosphatase.

Single administration of ethanol or alcoholic beverages (5g ethanol/kg body weight) induces a decrease of the 24h excretion of fecal intestinal alkaline phosphatase (I-AP) activity of 28% (P less than 0.05) in comparison to controls (0.9% saline). Administration of higher amounts of 20% (v/v) ethanol (8g/kg body weight on 3 consecutive days) yields a decrease of fecal I-AP excretion up to 82% (P less than 0.005) in comparison to controls (saturated glucose solution). The interpretation of these results as a toxic effect of ethanol to small intestinal mucosa was supported by measurement of enzymatic activity in the small intestinal mucosa and by morphometric data.

Alkaline Phosphatase↗

Preparation of monospecific antisera for immunoassay of human placental (Regan) and intestinal alkaline phosphatase.

The preparation of monospecific antisera for immunoassays of human placental (P-AP, Regan) and intestinal (I-AP) isoenzymes necessitates complete absorption of the antisera with heterologous antigen. Large scale preparation of pure human I-AP for absorption of anti-P-AP sera is not practical since a large amount of fresh intestine is required. Calf I-AP cross-reacts with human I-AP, but evidence is presented that this antigen is not suitable for absorption of anti-human-P-AP sera. In contrast, human I-AP can be extracted from faeces of patients under polychemotherapeutic treatment and used for the complete absorption of anti-human-P-AP sera. Monospecific anti-human-I-AP sera, suitable for immunofluorescence studies, can be obtained by a two-step affinity chromatography procedure: (1) human I-AP is removed from an extract of small intestine by antibodies to cross-reacting calf-I-AP, and (2) this small intestinal mucosal extract, free of human I-AP, can be used for the absorption of anti-human-I-AP sera. Finally, we present evidence that antibodies to calf-I-AP precipitate human-I-AP and can be used in immunoassays for I-AP in man.

Absorption↗

[A method for the determination of liver alkaline phosphatase in feces and their activity in intra- and extrahepatic cholestasis (author's transl)].

Using precipitating antibodies to human liver alkaline phosphatase (L-AP), a quantitative method is evaluated for the determination of L-AP-activity in feces. Normal controls (n = 42) exhibit a logarithmic normal distribution. Patients with intrahepatic cholestasis (n = 36) demonstrate an increase, patients with extrahepatic cholestasis (n = 23) a decrease of the fecal L-AP-activity. Variations of fecal L-AP-activities due to a varying water content of the stools could be excluded by simultaneous determination of intestinal AP-activity. Prae- and postoperative determinations in 12 patients with extrahepatic cholestasis yielded an increase of L-AP-activity after reconstructive surgery. In intrahepatic cholestasis, high fecal L-AP-activities are found together with relative low total AP-activities in the serum whereas in extrahepatic cholestasis low fecal L-AP-activities are associated with relative high total AP-activities in the serum.

Alkaline Phosphatase↗

[Activity of small intestine alkaline phosphatase in the feces in chronic intestinal diseases].

In comparison to normal controls (n = 71) the activity of intestinal alkaline phosphatase in feces is reduced in chronic bowel disease using an immunoprecipitation method: patients with Crohns disease (n = 40) or inactive ulcerative colitis (n = 29) demonstrate small changes of fecal intestinal alkaline phosphate activity in comparison to normal controls. Intestinal alkaline phosphatase is reduced in patients with active ulcerative colitis (n = 11) to 50%, in patients with uraemic enteropathy (n = 18) to 30% and in patients with coeliac disease (n = 14) to 20% of the activity observed in normal controls. During cytostatic treatment of malignant tumors, fecal intestinal alkaline phosphatase activity increases as a sign of toxic damage of the intestinal mucosa.

Alkaline Phosphatase↗

Fecal intestinal alkaline phosphatase in coeliac disease.

The intestinal alkaline phosphatase (I-AP) in feces was investigated in 16 patients with adult coeliac disease and 2 patients with gluten-sensitive enteropathy in dermatitis herpetiformis using an immunoprecipitation method. The mean concentration of I-AP activity in feces was reduced by 76% in patients with coeliac disease in comparison to normal controls (11.5 : 47.5 U/g). Patients with total villous atrophy (mean = 5.3 U/g) demonstrated a lower activity than patients with partial villous atrophy (mean = 14.3 U/g). Follow-up studies showed stable fecal I-AP-activities in symptom-free patients, whereas patients with relapses were characterized by fluctuating activities. The administration of a single oral dose of 31 g gluten is followed by a fecal I-AP-excretion pattern similar to toxic damage of the small bowel mucosa.

Alkaline Phosphatase↗

Carcinoembryonic antigen and ferritin in patients with lung cancer before and during therapy.

Carcinoembryonic antigen (CEA) levels were determined in 114 patients with confirmed lung cancer at the time of diagnosis using the CEA Ire-Sorin radioimmunoassay. Elevated CEA values were found in 47%. Most of the patients with high CEA levels had clinically detectable metastases. Ferritin was detectable by the Laurell-electrophoresis in the serum of 58 out of 81 (72%) of the patients with confirmed lung cancer at the time of diagnosis. Ferritin levels were significantly higher in patients with metastases. Serial measurements of CEA and ferritin during radio- and chemotherapy showed that the assay may be useful to evaluate the effects of therapy. Because of some false negative results both CEA and ferritin determinations should be used only in context with other clinical and laboratory findings.

Carcinoembryonic Antigen↗

[Carcinoembryonic antigen (CEA) in patients with lung cancer: correlation with tumour extent and response to treatment (author's transl)].

Carcinoembryonic antigen (CEA) was determined at the time of diagnosis in 90 patients with lung cancer. CEA levels were elevated in 47 (52%). High CEA levels were often associated with the presence of metastases. Serial CEA determinations in 40 patients, before and after radiotherapy and chemotherapy, revealed that patients who responded to treatment had a decreased CEA level, whereas those with progressive tumour growth had increased ones. CEA assay may, therefore, be useful in detecting metastases and in helping to assess the effect of treatment in patients with lung cancer.

Adult↗

Carcinoembryonic antigen, alpha 1-fetoprotein, ferritin, and alpha 2-pregnancy associated glycoprotein in the serum of lung cancer patients and its demonstration in lung tumor tissues.

Levels of carcinoembryonic antigen (CEA), alpha-fetoprotein (AFP), ferritin and alpha 2-pregency associated glycoprotein (alpha-2-PAG) were determined in patients with confirmed lung cancer at the time of diagnosis and in serial determinations during and after radio- or chemotherapy. Whereas AFP levels were not elevated in patients with lung cancer, increased levels of CEA, ferritin and alpha-2-PAG were found in more than 50% of the patients. The results suggest that determination of CEA, ferritin and alpha-2-PAG in the serum of patients with lung cancer may be useful to detect metastases or recurrences and to monitor the results of treatment. Furthermore, in this study CEA and ferritin could be demonstrated in extracts of lung tumor tissues by specific antisera.

Carcinoembryonic Antigen↗