Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P17174 (aspartate aminotransferase)
 14,872 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Age fractionation of erythrocytes is useful for further studies of the pharmacokinetics of methotrexate (MTX) in red blood cells. We separated erythrocytes from five blood donors and four patients at different time points after MTX infusions, using discontinuous Percoll gradients consisting of four solutions with a difference of 3% in density among them. The procedure yielded five distinct fractions of erythrocytes of increasing mean cell age as judged by declining reticulocyte enrichment and erythrocyte aspartate aminotransferase activity among the five fractions. MTX concentrations of the erythrocytes were measured at different times in connection with five 24-h MTX infusions (0.7-4 g/m2) on 14 occasions. Two days after completion of MTX infusion, no MTX was detected in the youngest erythrocyte population in two patients. Seven days after the infusion, the highest MTX concentrations were found in the youngest red blood cells. Ten to fourteen days following the MTX treatment, considerably lower MTX concentrations were found in the young red blood cells, and the MTX-containing erythrocytes seemed to have moved down the gradient. Just before the next MTX infusion (after 28 days) no MTX could be detected in the young erythrocytes. The MTX concentrations at that time were highest in the oldest erythrocyte fractions. This study shows more directly that MTX is incorporated in the red cell precursors of the bone marrow. The pharmacokinetics demonstrated correspond to a maturation time of the erythroblasts of about 7 days.
Cancer Chemother Pharmacol 1986
PMID:Methotrexate pharmacokinetics in age-fractionated erythrocytes. 346 79

The morphological characteristics and the production of biochemical markers were determined for 8 human tumor cell lines grown in artificial capillary culture. Comparisons were made with nude mouse xenografts and conventional monolayer or suspension cultures. Capillary histologies reproduced the features of neoplastic differentiation and glandular formation exhibited by the original human tumors and xenografts. The concentrations of specific biochemical markers, such as carcinoembryonic antigen, aspartate aminotransferase, and immunoglobulin, were higher in the pericellular culture medium in capillary culture. The capillary environment influenced the expression of biochemical heterogeneity by the DLD-1 colon carcinoma cell line and its derivative clones. Spontaneous differentiation of K562 leukemia cells was increased in the capillary system. These results indicate that the artificial capillary is a useful and relevant system for the study of cultured human tumor cells.
J Natl Cancer Inst 1987 Jul
PMID:Artificial capillary culture studies of human tumor cell growth, differentiation, and marker production. 347 51

The value of scalp cooling in the prevention of alopecia was investigated in 32 patients with advanced breast cancer who were given a mean of four courses of 40-80 mg/m2 of epirubicin. None of the 15 patients free from liver metastases who received scalp cooling required a wig, whereas four of eight similar patients who did not receive scalp cooling did require a wig. Abnormalities of aspartate transaminase and alkaline phosphatase pretreatment were predictive for reduced efficacy of scalp cooling, but not a contraindication to its use.
Cancer Treat Rep 1987 Oct
PMID:Effectiveness of scalp cooling in reducing alopecia caused by epirubicin treatment of advanced breast cancer. 347 18

The occurrence of liver metastases was evaluated by ultrasonic scanning and correlated with prognostic factors, pattern of metastases, clinical examination, biochemical liver function tests from serum, and liver biopsy specimens in 394 consecutive evaluable patients with first recurrence of breast cancer. Fifty-nine patients (15%) had a positive scan, and liver metastases were the only sign of recurrent disease in 11 of these patients. The presence of liver metastases was not associated with age, menopausal status, size of the primary tumor, regional lymph node status, or the length of the recurrence-free interval; but patients with liver metastases were significantly closer to the menopause than those without (P = 0.02). The diagnostic value of clinical examinations was comparable to that of serum bilirubin and serum aspartate aminotransferase (ASAT) analyses, but was significantly better than alkaline phosphatase (AP) and lactate dehydrogenase (LDH) analyses. Analysis of serum AP was not a valuable diagnostic tool in the diagnosis of liver metastases, since it was elevated in 58% of the patients with bone metastases, and since metastases in this site were found in one third of the patients without liver metastases. If all four tests were negative, liver metastases were excluded in 99% of the patients, and if more than two of the four tests were positive, liver metastases were found in 95%. Valid (greater than 80%) diagnosis of liver metastases by serum LDH or serum ASAT alone, required an elevation of three or five times the upper normal limits, respectively. Thirty-nine patients with positive ultrasonography results underwent biopsy. The ultrasonographic diagnosis could not be confirmed histologically in three patients (8%). If ultrasonic scanning had not been performed routinely, only one of 213 patients (0.5%) with soft tissue metastases would have been offered local therapy rather than systemic treatment. These data suggest that ultrasonic scanning of the liver should not be a routine diagnostic tool in examination of patients with first recurrence of breast cancer. However, whenever indicated by clinical signs or elevated blood tests, scanning should be performed to confirm the presence of liver metastases, particularly in patients entering therapeutical trials, since liver metastases demonstrated by ultrasound examinations may serve as a measurable parameter.
Cancer 1987 Apr 15
PMID:Incidence and methodologic aspects of the occurrence of liver metastases in recurrent breast cancer. 354 42

A study of C3H mice implanted with mammary tumours has shown that the levels of serum total protein, alanine transaminase and alkaline phosphatase are all lower than those found in normal mice, while aspartate transaminase is higher. Serum urea values were similar to normal levels, but creatinine was lower in males and higher in females. In the male mice, urine protein and urine N-acetyl-beta-D-glucosaminidase (NAG) activity were lower than in normal mice. Comparisons were made with age and sex matched controls which was found to be important for alkaline phosphatase, as this was shown to decrease with increasing age of the mice over the period from 10-30 weeks of age. The analyte values found in this study provide useful base-line data for assessing biochemical toxicity of cancer chemotherapy agents. It has been shown that some of these values can vary with age, or can be different if tumour-bearing mice are used instead of normal mice.
Br J Cancer 1985 Oct
PMID:The effect of C3H mouse mammary tumour on the levels of serum and urine analytes in vivo. 406 36

Involution of the thymus was observed in rats bearing AH 130 (solid-type) tumors. The thymus weight decreased with tumor growth. Daily injection of a pharmacological dose of hydrocortisone into normal rats resulted in involution of the thymus and marked increase in alanine aminotransferase activity. This treatment also caused slight increase in the activity of tyrosine aminotransferase but not of aspartate aminotransferase in these animals. Involution of the thymus in tumor-bearing rats, however, was not accompanied by appreciable increases in the activities of these aminotransferases, even at an advanced stage of tumor growth when the plasma corticosterone level was very high and significant increase in the activities of all these enzymes was observed in the liver. Further, additional injections of hydrocortisone into rats with tumors weighing more than 5% of the body weight did not cause any appreciable change in alanine aminotransferase activity in the thymus, although in rats with smaller tumors it slightly increased the enzyme activity in the thymus. Furthermore, in normal rats, increase in alanine aminotransferase activity in the thymus with involution of the glands was observed with a dose of corticosterone close to the physiological range attained in rats with tumors in an advanced stage.
Cancer Res 1980 Mar
PMID:Aminotransferase activities and involution of the thymus in rats bearing AH 130 tumors. 611 Apr 78

Immunochemical techniques with enzymes as the antigen have grown in frequency during the last few years. These techniques have allowed evaluation of enzymes in the presence of endogenous inhibitors. Among those enzymes measured by immunochemical techniques and which have found diagnostic application, mention will be made of alkaline phosphatase (with particular reference to the intestinal, placental, and Regan isoenzymes), lactate dehydrogenase (in which renewed interest has developed due to techniques for specifically measuring the LD-1 isoenzyme), aspartate aminotransferase (of which the cytosolic and mitochondrial forms can now be independently measured by immunochemical techniques), acid phosphatase (for which a specific immunochemical assay for the prostatic enzyme has been widely introduced in diagnostic laboratories), and creatine kinase (for which a variety of immunochemical techniques to measure the M- and B-subunits are now part of standard laboratory assays). Other enzymes which will be discussed in this review include phosphohexose isomerase, amylase, ribonuclease, and lysozyme (muramidase). Finally, the use of enzymes, particularly asparaginase, in the chemotherapy of cancer will be outlined.
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PMID:Immunoassay of enzymes--an overview. 634 26

The activities of aspartate aminotransferase and alanine aminotransferase in erythrocytes with and without the addition of pyridoxal phosphate were determined in healthy controls and in Indian women with cancer of the uterine cervix. The percent stimulation of the erythrocyte transferases as a result of the addition of pyridoxal phosphate was negligible in the case of normal subjects (less than 5% stimulation). In the patients with cervical cancer, a 23-35% stimulation was observed, indicating a deficiency of vitamin B6. It is not yet known whether the deficiency is the cause of the disease or due to the tumor.
Nutr Cancer 1984
PMID:Vitamin B6 status in patients with cancer of the uterine cervix. 654 76

Acute necrosis of R3230AC mammary tumor or thyroid carcinoma subcutaneously implanted in F344 rats was achieved by injection of a strongly hypertonic hexose and serotonin solution at 37 degrees C into and around the tumors. Changes in gross metabolism, hematology, and blood chemistry were then followed over a 9-day period, and they were most marked during or at the end of the first 24 hours. Food intake of the rats was sharply reduced, whereas drinking and diuresis were increased. Marked hemodilution and increased serum concentrations of aspartate aminotransferase, potassium, and uric acid were observed, as well as stable serum concentrations of sodium and chloride. Glucose overload, as opposed to fructose overload, led to secondary hypoglycemia. From day 2 food consumption returned to normal and increased thereafter. Water intake and urine output remained high. After an initial loss, body weight caught up with that of control rats. Hematocrit recovered partially, whereas blood chemistry progressively returned to about normal values.
J Natl Cancer Inst 1983 May
PMID:Systemic tolerance of osmotically induced oncolysis in rats. 657 33

Clone A human colon adenocarcinoma cells were grown in three-dimensional artificial capillary culture (ACC) to determine responses of capillaries treated 3 weeks after tumor cell inoculation with a specific, easily quantifiable cytotoxic agent, ionizing radiation. The high-density growth of tumor cells in ACC can be considered to be an in vitro analogue of a solid tumor. Changes in extracapillary space (ECS) fluid concentrations of lactate dehydrogenase (LDH) and aspartate aminotransferase (GOT) and the utilization of glucose in circulating medium were monitored after a supralethal radiation dose (90 Gy) of X-rays. Immediately after irradiation, increased levels of LDH and GOT were found that reached maximum levels about four to five times those found in nonirradiated control capillaries at 10-13 days post irradiation and then declined. Patterns of enzyme production appeared to correlate with the numbers of nonviable tumor cells collected from the ECS of the artificial capillaries. In contrast, glucose utilization showed little correlation with either enzyme concentration or dead cell production. It was determined that, while capillaries grown and treated in this manner appear to respond in a dose-dependent manner to ionizing radiation (as indicated by changes in LDH and GOT levels), these particular end points are relatively insensitive and are not suitable for studies in which therapeutic levels of X-radiation might be given. In other studies, tumor cells were removed from unirradiated capillaries by trypsinization and used to obtain complete survival curves after graded doses of X-radiation. The dose-response curves obtained indicate that clone A colon tumor cells grown in ACC show a marked decrease in their ability to accumulate sublethal radiation injury as compared to responses of these cells growing exponentially in asynchronous monolayer cultures, to synchronized mid-G1 tumor cells, or to tumor cells in stationary growth phase. These data suggest that ACC is a potentially useful model to study the effects of cytotoxic agents on human tumor cells.
J Natl Cancer Inst 1984 Jun
PMID:X-ray responses of human colon tumor cells grown in artificial capillary culture. 658 47


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