Metabolite monitoring

A 29-year-old man presented with acute pancreatitis after a period of heavy cannabis smoking. Other causes of the disease were ruled out. The pancreatitis resolved itself after the cannabis was stopped and this was confirmed by urinary cannabinoid metabolite monitoring in the community. There were no previous reports of acute pancreatitis associated with cannabis use in the general population. Drugs of all types are related to the etiology of pancreatitis in approximately 1.4-2% of cases k Pancreatic toxicity. The dried leaf, smoked by a 19-year-old woman, was active. The subject was hospitalized with pancrea-titis . 

Altogether, no consensus recommendations on therapeutic ranges for 6-MP and 6-TG metabolite monitoring in treatment of childhood ALL are currently available. Moreover, 6-TGN levels may be biased in individuals who have received repeated RBC transfusions due to high variability in TPMT activity of transfused donor RBC. 

Gearry RB, Barclay ML. Azathioprine and 6-mercap-topurine pharmacogenetics and metabolite monitoring in inflammatory bowel disease. J Gastroenterol Hepatol. 2005 20 1149-1157. 

HPLC has played an important role for years in the drug discovery process in pharmaceutical laboratories. HPLC has proven a valuable asset in purifications of drug from de novo synthesis, from biological matrices, and from combinational synthesis. HPLC assay has moved from the discovery laboratory on through manufacturing, production, and metabolite monitoring. 

Urinary Metabolite Monitoring 28 Salivary Monitoring 29 VALIDATION OF PASSIVE DOSIMETRY 30 Atrazine 30 Chlorpyrifos 31... 

DISULFIRAM PROTON PUMP INHIBITORS -OMEPRAZOLE Possible T adverse effects of disulfiram Accumulation of metabolites Monitor closely for T side-effects, although patients have received combinations without reported problems... 

IFOSFAMIDE 1. ANTIBIOTICS -clarithromycin, erythromycin 2. ANTIFUNGALS -fluconazole, itraconazole, ketoconazole voriconazole 3. ANTIVIRALS-efavirenz, ritonavir 4. GRAPEFRUIT JUICE 5. H2 RECEPTOR BLOCKERS - cimetidine 1 plasma concentrations of 4-hydroxyifbsfamide, the active metabolite of ifosfamide, and risk of inadequate therapeutic response Due to inhibition of the isoenzymatic conversion to active metabolites Monitor the efficacy of ifosfamide clinically and t dose accordingly... 

NELFINAVIR RITONAVIR AND LOPINAVIR Possibly 1 efficacy of lopinavir and ritonavir, and t efficacy of nelfinavir i bioavailability of lopinavir and ritonavir, but t minimum plasma levels of nelfinavir and its active metabolites Monitor closely. May need to T doses of lopinavir and ritonavir... 

The severe fiver dysfunction also seemed to be more common in slow metabofizers, and it was proposed that this due to a deficiency in detoxication of a metabolite. Monitoring patients with fiver function tests is one way to avoid this adverse effect. There may be other factors as well as the acetylator phenot5rpe that are important, such as other drugs being taken at the same time. Excessive and sustained alcohol intake may also be a factor, as this is quite commonly associated with the occurrence of tuberculosis. Apart from weakening the fiver it will also increase the amount of the enzyme that produces the toxic metabolite of isoniazid. 

As depicted in Figure 1.16, (electrochemical) biosensors are either placed in laboratory animals for fundamental (patho-) physiological and neurochemical in vivo measurements or implanted in the human body for health check purposes and metabolite monitoring. In the field of in vivo medical research, enzyme-based... 

Quantitation of metabolites is challenging in the absence of radiolabel or authentic standards. The most commonly used methods for metabolite monitoring are detection by ultraviolet (UV) absorbance and by mass spectrometry. When UV absorbance is being used for detection, the peak response will be approximately proportional to the amount of metabolite if the chromophore is not altered, such as hydroxylation of an aliphatic side group. However, if the molecule is cleaved, altering conjugated systems, relative UV peak responses may not accurately represent the relative amounts of parent compound and each metabolite. Mass spectrometry is even less reliable than UV absorbance in the absence of authentic standards, as ionization efficiency for each detected molecule will differ. In practice, a combination of UV and mass spectrometry is most appropriate. However, unlike the substrate depletion approach, the possibility would still exist of missing metabolites if the detection method does not pick up the metabolite of interest. 

This type of scan has a distinct analytical potential because the loss of a common neutral fragment can be taken as an indication of a particular class of compounds. Therefore, it has been applied in the search for specific compounds derived from a certain precursor compound (drug/metabolite monitoring). 

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