Mayo Clinic studies

Not to be overlooked is vitamin C, as previously described, and the work of Cameron and Pauling (1993), and of Hoffer (2000). Separate chapters are contained in both Moss (1992) and Pelton and Overholser (1994). The controvCTsy over the Mayo Clinic studies is reviewed objectively, and it is stressed that vitamin C works only if the immune system has not been damaged by chemotherapy. Moreover, there is said to be a rebound effect with vitamin C, whereby a sudden stoppage severely depletes the blood serum levels. The patient should be taken off slowly. 

Tsalic M, Bar-Sela G, Beny A et al. Severe toxicity related to the 5-fluorouracil/leucovorin combination (the Mayo Clinic regimen) a prospective study in colorectal cancer patients. Am J Clin Oncol. 2003 Feb 26 103-106. 

Taylor and colleagues [98] at the Mayo Clinic published a method for the simultaneous analysis of urinary cortisol and cortisone. They used 2H4 cortisol as an internal standard and took a 0.5-ml urine sample. An API 2000 with Turboion-spray source was used in the positive-ion mode. Chromatography was conducted on a standard-bore C18 column with Q8 precolumn filter. MRM was conducted in the positive-ion mode monitoring m/z 363—>121 for cortisol, 367—>121 for 2TL, cortisol, and 361— -121 for cortisone. Cortisol and cortisone were separated and both were eluted within 2 min. Inter- and intra-assay variation for both compounds was < 9% for amounts above 2 pig/dl. The values obtained agree well with those of other studies, such as ours (Table 5.3.2) [62]. They found a range for cortisol for adult males of 4.2-60 pg/24 h and for adult females 3.0-43 pg/24 h. In summary, the 3-min run time of their method has allowed the Mayo group to completely transfer their cortisol and cortisone workload from RIA and HPLC to MS/MS. 

Sternby, B., O Brien, J. F., Zinsmeister, A. R., and DiMagno, E. P., What is the biochemical test to diagnose acute pancreatitis A prospective clinical study. Mayo Clin. Proc. 71, 1138-1144... 

Butt HR, Allen EVj Bollman JL, A preparation from spoiled sweet clover (3,3 )-methylene-bis-(4 hydroxycoumarin) which prolongs coagulation and prothrombin time of the blood preliminary report of experimenta and clinical studies, Proc Staff Meet Mayo Clin 1941 16 388-395. 

In a study from the Mayo Clinic (M4), a group of male patients undergoing diagnostic coronary angiography for chest pain or suspected coronary artery disease had plasma cholesterol and triglyceride, HDL cholesterol, and apoA-I concentrations measured. Whereas HDL cholesterol discriminated to some extent between those with and those without important coronary artery disease (and total cholesterol and triglyceride did not discriminate at all), apoA-I levels provided an almost perfect prediction of obstructive coronary artery disease. Some caveats on the interpretation of apoA-I levels in this and other studies have been noted by Blackburn (B34). 

Two Phase III clinical studies of orally administered capecitabine in over 1,200 patients with untreated metastatic colorectal cancer demonstrated at least equal efficacy and improved tolerability versus the Mayo Clinic regimen of intravenous 5-fluorouracil/leucovorin administration. The overall response rate for patients taking capecitabine orally was 21%, versus 14% for the intravenous 5-FU/leucovorin regimen. A median 53-month follow-up revealed a three-year disease-free survival rate of 66% for capecitabine versus 63% for 5-FU/leucovorin patients. International Phase II trials also demonstrated therapeutic benefits of capecitabine monotherapy for women with metastatic breast cancer that was either resistant to both paclitaxel and anthracycline therapy. Orally administered at the twice-daily 1,250 mg/m2 regimen (cycles of two weeks of therapy followed by a week of rest), the tumor response rate was in the range of 20-25%. In addition, combination of capecitabine with a taxane yielded a unique survival benefit compared to the previous standard of taxane monotherapy for anthracycline-resistant breast cancer.13,14... 

In a clinical report from the Mayo Clinic by Rosenbaum (1979), depression was found to be closely linked to TD. Rosenbaum stated, Almost all patients in our series had depressive symptoms accompanying the onset of tardive dyskinesia, and he cited other studies confirming his observation. 

A study of 261 patients who received warfarin for 221 patient-years reported major haemorrhage in 5.3% after 1 year and 10.6% after 2 years. Gitter M J et al 1995 Mayo Clinic Proceedings 70 725-733. 

Hench P S et al 1949 The effect of a hormone of the adrenal cortex (17-hydroxy-ll-dehydrocorticosterone Compound E) and of pituitary adrenocorticotrophic hormone on rheumatoid arthritis. Proceedings of the Staff Meetings of the Mayo Clinic 24 181,277 (acute rheumatism). The classic studies of the first clinical use of an adrenocortical steroid in inflammatory disease. See also page 298 for an account by E C Kendall of the biochemical and pharmaceutical background to the clinical studies. Kendall writes of his collaboration with Hench, he can now say "17-hydroxy-ll-dehydrocorticosterone" and in turn I can say "the arthritis of lupus erythematosus". In sophisticated circles, however, I prefer to say, "the arthritis of L.E. ". 

The hypothesis that intravenous fluid that contains sodium bicarbonate might decrease the incidence of CIN compared with NaCl was recently tested in some randomized trials [113-116]. The hypothesis for a potential benefit of bicarbonate is based on the concept that alkalinizing tubular fluid reduces the generation of injurious hydroxyl radicals. Within a retrospective Cohort Study of 7977 Patients at Mayo Clinic N-ace-tylcysteine alone and in combination with sodium bicarbonate was not associated with any significant difference in the incidence of contrast nephropathy. The use of intravenous sodium bicarbonate was associated with increased incidence of contrast nephropathy [117]. As with any retrospective study confounding by indication is always exists since patients at preceived high risk often receive the treatment that is suspected of being superior even when unproven. 

To summarize this section, PT programs are far from ideal monitors of laboratory performance. In a study of PT survey problems at the Mayo Clinic, more than one half of the errors on surveys were directly related to deficiencies in the surveys (such as invalid specimens and inappropriate evaluation criteria), and only 28% could be linked to specific analytical problems. A novel PT program piloted by the New York State Department of Health involves obtaining aliquots of patient specimens that are routinely processed by the laboratory at the time of its annual inspection. These specimens are reanalyzed in the state s laboratories using reference methods, and the results are compared with those obtained during inspection. This prevents problems such as the presence of unnatural specimens and the clerical errors of foreign forms. Other specimen stability problems and methodological interferences probably continue to exist. 

Methods that involve studying the disposition of some exogenously administered agent (e.g. indocyanine green, antipyrine, galactose or dextromethorphan) have now been superceded by functional (often multicomponent) tests. Mono-ethylglycinexylidide formation has not found wide acceptance. More complicated Cox proportional hazards models may exist for other liver diseases, but are only used specifically for them (e.g. the Mayo Clinic Survival Model for primary biliary cirrhosis see the US FDA Guidance). 

The Fen-Phen combination regimen started in 1992 after the publication of an article that showed dramatic weight loss when both drugs were taken together. In 1995, the FDA was asked to approve a new diet drug, dexfenfluramine or Redux. Developed by Interneuron Pharmaceuticals Inc., a Massachusetts company, Redux is a purified form of fenfluramine. However, prior reports had linked fenfluramine use with primary pulmonary hypertension (PPH), a rare but potentially fatal cardiopulmonary disease. The FDA finally approved fenfluramine and Redux went on the market in April 1996. In July 1997, the Mayo Clinic released results from a study that found 24 cases of heart... 

M17. Maytum, W. J., Goldstein, N. P., McGuckin, W. F., and Owen, C. A., Jr., Copper metabolism in Wilson s disease, Laennec s cirrhosis and hemachromatosis Studies with radiocopper (Cu ). Proc. Staff Meetings Mayo Clinic 36, 641-660 (1961). 

NSAID induced nephrotic syndrome is suspected of being immunologically mediated and idiosyncratic. It has a distinct presentation when compared to that ascribed to acute interstitial nephritis. The nephrotic syndrome is not associated with hemodynamically stressed patients. Recently Radford etal. [%] published a retrospective study of NSAIDs induced membranous nephropathy using the Mayo Clinic biopsy registry. They reported that >10% of biopsy proven membranous glomerulonephritis [stage I/II] was attributable to NSAIDs. They summarized the clinical features of... 

In June 2000, the Mayo Clinic Proceedings published a major study and an editorial reminding us of and reiterating the pivotal role of the autopsy in scientific medicine. The authors, a group of Belgian physicians, compared the... 

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