1/18. Toxicity of irinotecan (CPT-11) and hepato-renal dysfunction.Various clinical and laboratory parameters have been investigated for their ability to predict toxicity arising from the use of the anticancer drug, irinotecan (CPT-11). In particular, patients deficient in the conjugation of SN-38, a metabolite of CPT-11, are known to be at greater risk. We describe one case of a patient with metastatic colorectal cancer treated with a single dose of CPT-11 at 125 mg/m(2). Although this patient lacked any known predictive factors for toxicity, he experienced severe side-effects several days later. We hypothesized that the toxicity in this patient was due to compromised SN-38 conjugation. plasma samples were analyzed by reversed-phase high-performance liquid chromatography assay for CPT-11 and its metabolites at 96, 144, 168, 192 and 288 h post-administration. We observed that the concentrations of both the parent drug and its metabolites were markedly raised (11- to 60-fold expected). Additionally the estimated terminal half-lives were 1.5-7 times those expected (29.5, 101, 39.6 and 41.8 h for CPT-11, APC, SN-38G and SN-38, respectively). We conclude that the toxicity in this patient was not caused by deficient SN-38 conjugation, but by decreased drug excretion through both hepatic and renal routes.- - - - - - - - - - ranking = 1keywords = chromatography (Clic here for more details about this article) |
2/18. Alpha-fetoprotein-producing male breast cancer accompanied with hepatocellular carcinoma: assessment by lectin-affinity profile.An autopsy case associated with both male breast cancer and hepatocellular carcinoma in which serum alpha-fetoprotein (AFP) was extremely elevated is described. The source of AFP production was investigated. In lectin-affinity chromatography of the patient's serum, concanavalin a (ConA) binding pattern was not consistent with that of hepatocellular carcinoma, and lens culinaris agglutinin A (LCA) affinity indicated a similar pattern to hepatocellular carcinoma. The immunohistochemistry staining for AFP revealed positive reactivity in breast cancer cells, but was negative in hepatocellular carcinoma cells. To the best of our knowledge, there have been no reports of breast cancer exhibiting immunohistochemically positive AFP in breast cancer cells. In the present case, ConA binding test was useful for identification of the source of AFP production. Furthermore, corresponding aggravation of breast cancer to the elevation of AFP suggested the possibility that AFP might enhance breast cancer growth.- - - - - - - - - - ranking = 1keywords = chromatography (Clic here for more details about this article) |
3/18. An unusual metastatic motilin-secreting neuroendocrine tumour with a 20-year survival. Pathological, biochemical and motility features.motilin-secreting neuroendocrine tumours have been rarely described. Immunohistochemical, biochemical and motility investigations were performed in a 62-year-old man with liver and bone metastases of a motilin-secreting neuroendocrine tumour originating from a rectal polyp removed 14 years previously. Symptoms related to liver metastases were reduced by a right hepatectomy whereas plasma motilin levels were decreased. The patient also underwent two operations for spinal cord decompression and survived 6 more years under medical treatment, mainly octreotide. immunohistochemistry revealed predominant expression of motilin-containing cells, with rare cells expressing somatostatin and pancreatic polypeptide, and staining for only one panendocrine marker, neurone-specific enolase. A liver tumour extract contained 17.9 microg motilin per gram of tissue, which permitted to isolate and characterize human motilin, which was identical to porcine motilin. plasma column gel chromatography revealed a main peak corresponding apparently to porcine motilin. The patient had no symptoms of disturbed motility. gastric emptying and gastroduodenojejunal motility were found within normal limits. The absence of alterations of gut motility was perhaps related to sustained autonomous motilin production. The long evolution of this type of tumour suggests that plasma motilin determination should be added to the investigations for neuroendocrine tumours.- - - - - - - - - - ranking = 1keywords = chromatography (Clic here for more details about this article) |
4/18. adrenal cortex, tumor, and peripheral production of deoxycorticosterone.A method is reported for the measurement of the urine excretion rates of tetrahydro-11-deoxycorticosterone (3 alpha,5 beta-THDOC), an important metabolite of 11-deoxycorticosterone (DOC). Quantification using gas chromatography/mass spectrometry (GC/MS) was achieved by comparing the ion fragment response for the molecular ion (m/z 507) of the analyte (as methyloxime trimethylsilyl ether derivative) to that of a fixed amount of an isomer of THDOC added to urine as internal standard. To improve the specificity of measuring THDOC in clinical samples, an additional Sephadex LH-20 chromatography step was introduced to separate 11-deoxycortisol and some progesterone metabolites. In the luteal phase of the menstrual cycle, THDOC excretion was higher than in the follicular phase; it was also higher than in women taking oral contraceptives. The correlation of THDOC with progesterone production, independent of a constant cortisol output, supports an ovarian or peripheral conversion of progesterone to DOC. The assay proved useful (1) in monitoring for the recurrence of a mineralocorticoid-secreting tumor and (2) when adrenal production of DOC was not fully suppressed in congenital adrenal hyperplasia due to 11 beta-hydroxylase deficiency. Under the latter circumstances, the renin-angiotensin system seemed to be an important regulator of DOC production.- - - - - - - - - - ranking = 2keywords = chromatography (Clic here for more details about this article) |
5/18. pharmacokinetics of imatinib mesylate in end stage renal disease. A case study.AIM: To evaluate the pharmacokinetics of imatinib mesylate (Glivec) and its main metabolite (CGP74588) in a patient with end stage renal disease on hemodialysis and compare it with published data from subjects with normal renal function. patients AND methods: Serial blood samples were collected over a 2-weeks period in a patient who was receiving daily 400 mg oral imatinib mesylate for the treatment of a gastrointestinal stromal tumor metastatic to the liver while on hemodialysis. plasma levels of imatinib and CGP74588 were determined by a liquid chromatography-tandem mass spectrometry assay. RESULTS: The pharmacokinetic values for imatinib and CGP74588, respectively, were: maximum concentration (3,340 and 781 ng/ml), time to maximum concentration (2 h), half-life (18.2 and 34.0 h), area under the curve (53.9 and 14.8 microg.h/ml), and trough concentration (1,540 and 508 ng/ml) for at least 24 h. All obtained values fell within the range of values of imatinib and its metabolite obtained in patients with normal renal function. dialysis courses were not found to intervene with plasma kinetics of the study drug. CONCLUSIONS: Our results indicate that the pharmacokinetics of imatinib and its metabolite CGP74588 do not change in patients with end stage renal disease on hemodialysis. Thus, the standard dose of imatinib can be safely administered to patients on hemodialysis, and probably with renal failure, at any stage.- - - - - - - - - - ranking = 1keywords = chromatography (Clic here for more details about this article) |
6/18. Partial characterization of an abnormal lactate dehydrogenase isoenzyme, LDH-1ex, in serum from a patient with hepatocellular carcinoma.serum from a patient with hepatocellular carcinoma contained an abnormal isoenzyme of lactate dehydrogenase (LDH; EC 1.1.1.27), LDH-1ex, that on electrophoresis on 10-g/L agarose gel migrated anodally to the LDH-1 band. This isoenzyme was partly purified by ultrafiltration and preparative electrophoresis. Gel chromatography and sodium dodecyl sulfate/polyacrylamide gel electrophoresis studies of the resulting LDH-1ex preparation suggested that this isoenzyme is probably a tetramer made up of four single polypeptide chains (monomers), each having a molecular mass of about 32,000 Da. LDH-1ex was heat stable and reacted more readily with 2-hydroxybutyrate than did the slower migrating LDH-4 and LDH-5 isoenzymes. LDH-1ex showed no activity when lactate was omitted from the substrate solution or replaced by ethanol.- - - - - - - - - - ranking = 1keywords = chromatography (Clic here for more details about this article) |
7/18. Ectopic production of parathyroid hormone by small cell lung cancer in a patient with hypercalcemia.Severe hypercalcemia (serum calcium, 4.37-4.84 nmol/L) was found in a 70-yr-old man who had a small cell carcinoma of the lung with multiple metastases. The plasma immunoreactive PTH concentration was markedly elevated, as measured in three different PTH assays [N-terminal PTH, 4,650 ng/L (normal, 230-630); midregion PTH, 13,850 ng/L (normal, 180-560); C-terminal PTH, 9,900 ng/L (normal, less than 1,300)], but at autopsy the parathyroid glands were histologically normal. The PTH concentration of a liver metastasis was 503.5 ng/g wet wt (normal liver, less than 4.2-5.9), and the PTH in the tumor extract eluted at nearly the same position as synthetic human PTH-(1-84) on gel filtration chromatography. Northern blot analysis revealed PTH mRNA in the tumor as a single band of 0.9 kilobase. These results indicate that the ectopic PTH production by the lung cancer was the cause of hypercalcemia in this patient.- - - - - - - - - - ranking = 1keywords = chromatography (Clic here for more details about this article) |
8/18. High plasma pancreastatinlike immunoreactivity in a patient with malignant insulinoma.High levels of pancreastatinlike immunoreactivity were detected in the plasma (2.9 pmol/ml, greater than 200-fold the normal level), pancreas (2.9 nmol/g wet wt, greater than 450-fold the normal level), and liver (1.6 nmol/g wet wt) of a patient with pancreatic insulinoma with metastasis to the liver by a sensitive and specific radioimmunoassay for human pancreastatin. Antiserum was produced against the C-terminal fragment of human pancreastatin-(24-52), which was synthesized according to the sequence of human chromogranin a corresponding to that of pancreastatin. With the antiserum, intense immunocytochemical staining was detected in the tumors. Sephadex G-50 gel filtration showed that the tumors and plasma contained two molecular forms of pancreastatinlike immunoreactivity--a molecular form coeluted with synthetic human pancreastatin-52 and a larger molecular form (Mr approximately 12,000-15,000). The smaller form eluted in the same position as synthetic human pancreastatin-52 on reverse-phase high-performance liquid chromatography.- - - - - - - - - - ranking = 1keywords = chromatography (Clic here for more details about this article) |
9/18. Malignant somatostatinoma presenting with diabetic ketoacidosis.High circulating levels of somatostatin (SRIF) were detected in a patient with a metastatic tumour after development of diabetic ketoacidosis (DKA). fasting insulin and c-peptide levels were markedly suppressed, but plasma glucagon was not suppressed below normal. Progressive cachexia ensued; at autopsy a poorly differentiated non-small cell neuroendocrine carcinoma metastatic to liver was found. Small gallstones were noted. Electron microscopy of tumour tissue showed neurosecretory granules and tonofilament bundles. Immunohistochemical staining of tumour cells was diffusely positive for carcinoembryonic antigen, bombesin-like immunoreactivity, and calcitonin with focal immunoreactivity for SRIF, serotonin, neuron-specific enolase, chromogranin, and epithelial membrane antigen. Column chromatography of plasma and tumour extract revealed five or more peaks of material with SRIF-like immunoreactivity (SRIF-LI): predominantly SRIF-28 and intermediates in tumour extract, and SRIF-14 and an intermediate between SRIF-28 and SRIF-14 in plasma, DKA in this case of somatostatinoma syndrome may reflect differential effects of tumour production of larger molecular weight SRIF forms on insulin and glucagon secretion.- - - - - - - - - - ranking = 1keywords = chromatography (Clic here for more details about this article) |
10/18. Secretory response and immunochemical heterogeneity of glucagon in plasma and tumor extracts of a patient with glucagonoma.The secretory response and immunoreactive heterogeneity of glucagon was investigated in a patient with glucagonoma syndrome. After glucose administration, abnormal insulin release accompanied by glucose intolerance were observed, whereas the high glucagon circulating levels were only partially blocked after glucose or somatostatin infusion. Chromatographic fractionation of plasma samples, before and after arginine administration showed that most of the immunoreactivity eluted as true glucagon. Furthermore, when aliquots of the tumor extracts were fractionated by column chromatography or by polyacrylamide gel electrophoresis, most of the immunoreactivity eluted in the 3,500 molecular weight peak. In contrast with previous reports, our results indicate that neoplasia A cells can also manufacture and release into the bloodstream great amounts of genuine glucagon rather than larger glucagon immunoreactive forms. In spite of such findings, in this patient neither diabetes nor hyperglycemia were present.- - - - - - - - - - ranking = 1keywords = chromatography (Clic here for more details about this article) |
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