The effects of literacy and education on the quantitative and qualitative aspects of semantic verbal fluency.

Semantic verbal fluency tasks are commonly used in neuropsychological assessment. Investigations of the influence of level of literacy have not yielded consistent results in the literature. This prompted us to investigate the ecological relevance of task specifics, in particular, the choice of semantic criteria used. Two groups of literate and illiterate subjects were compared on two verbal fluency tasks using different semantic criteria. The performance on a food criterion (supermarket fluency task), considered more ecologically relevant for the two literacy groups, and an animal criterion (animal fluency task) were compared. The data were analysed using both quantitative and qualitative measures. The quantitative analysis indicated that the two literacy groups performed equally well on the supermarket fluency task. In contrast, results differed significantly during the animal fluency task. The qualitative analyses indicated differences between groups related to the strategies used, especially with respect to the animal fluency task. The overall results suggest that there is not a substantial difference between literate and illiterate subjects related to the fundamental workings of semantic memory. However, there is indication that the content of semantic memory reflects differences in shared cultural background--in other words, formal education--, as indicated by the significant interaction between level of literacy and semantic criterion.     

Molecular heterogeneity of somatostatin analogue BIM-23014C receptors in human breast carcinoma cells using the chemical cross-linking assay.

Distinct proteins complexed with somatostatin and the somatostatin analogue BIM-23014C were revealed in human breast cancer cells using the cross-linking assay. One BIM-23014C-specific complex (Mr 57,000) was observed in MCF-7 (monolayer, nodule, and tumor) and T47D. Growth inhibition of MCF-7 tumor xenografts by BIM-23014C was dose related in the 6-day subrenal capsule assay. Three complexes (Mr 27,000, 42,000, and 57,000) were detected in MDA-MB-231, and no complex was visible in HBL-100. No correlation was found between receptors for BIM-23014C and epidermal growth factor in these lines. Twenty-seven of 30 human breast tumors (90%) had at least one BIM-23014C receptor. Sixteen had three complexes (Mr 27,000, 42,000, and 57,000). Six had the two complexes (Mr 27,000 and 57,000), two had Mr 42,000 and 57,000 complexes, two had just the Mr 27,000 complex, and one had just the Mr 42,000 complex. The presence of the three BIM-23014C receptors was positively correlated (P less than 0.05) to the low amount of sex steroid receptors (less than 20 fmol/mg) [seven of eight (estrogen receptor negative, progesterone receptor negative) versus four of 14 (estrogen receptor positive, progesterone receptor positive)]. Another positive correlation was established between the absence of progesterone receptors and the presence of these three complexes [12 of 16 (progesterone receptor negative) versus four of 14 (progesterone receptor positive)]. This high percentage of BIM-23014C receptor-positive biopsies and its inhibitory activity would support its clinical potential for the treatment of breast cancer.     

P-glycoprotein,multidrug resistance and tumor progression

P-glycoprotein (Pgp) is a plasma membrane protein that was first characterised in multidrug resistant cell lines. The occurrence of Pgp in clinical tumors has been widely studied. Recent investigations have begun to focus on the relationship between Pgp detection in tumors and treatment outcome. In several types of tumors, detection of Pgp correlates with poor response to chemotherapy and shorter survival. P-glycoprotein overexpression often occurs upon relapse from chemotherapy but may also occur at the time of diagnosis. Studies of experimental rat liver carcinogenesis have shown that Pgp expression increases in late stages of carcinogenesis, suggesting that Pgp may be involved in tumor progression. While some of the Pgp isoforms are known to transport hydrophobic chemotherapeutic drugs out of tumor cells, the biologic effects of Pgp overexpression in tumor cells are not fully understood, because the spectrum of substrates for Pgp-mediated transport has not been determined. In the rat liver carcinoma model, strong expression of Pgp is associated with a highly vascular stroma, suggesting that Pgp in tumor cells may affect the connective tissue stroma. The regulation of Pgp appears to be complex, and little is known about how it is up-regulated during carcinogenesis. Further studies of the role of Pgp in malignancy may contribute to our understanding of molecular mechanisms which underlie tumor progression.     

Evaluation of renal transplant dysfunction by duplex Doppler sonography: a prospective study and review of the literature

A disconcertingly wide variation exists in the literature as to the accuracy of duplex Doppler sonography in the detection of acute renal transplant rejection. Sensitivities range from 9% to 76%. In an attempt to explain the disparity of results, we undertook a double-blind prospective study of the accuracy of duplex Doppler ultrasound in the detection of acute rejection in renal transplants. We scanned 49 consecutive patients with a total of 65 biopsies; 46 biopsies in 33 consecutive patients were included in our study. In our population, the prevalence of acute rejection was 61% (28/46). Using a resistive index (RI) cutoff of greater than 0.90 based on the main renal artery flow pattern, the sensitivity of our test was 43%, with a 67% specificity. The positive predictive value was 67%. Our results are contrasted and compared with the published data from other groups in a critical survey of the literature. We conclude that duplex Doppler sonography alone is inadequate to evaluate acute rejection in renal transplants.     

A patient with hyperkalemia and metabolic acidosis

Uptake of potassium by extrarenal tissues, primarily muscle and liver, represents a major defense mechanism in the maintenance of normokalemia following an acute elevation in the serum potassium concentration. Insulin, epinephrine, and aldosterone all play major roles in maintaining the normal distribution of potassium between the intracellular and extracellular environment. In addition to hormonal regulation, changes in blood pH and tonicity also exert a strong influence on extrarenal potassium metabolism. Last, the serum potassium concentration per se directly influences its own cellular uptake and this transport mechanism appears to be inhibited by uremia.     

Home-based Health Risk Appraisal and screening program

In an effort to improve Health Risk Appraisals and to induce individuals to change their lifestyles, comprehensive evaluations and counseling sessions were carried out for 476 participants of an experimental preventive care program (1984). Nurse practitioners interviewed participants in their homes and collected information about their lifestyle, medical history, and family history. In addition, physical examinations were performed and blood samples were obtained for laboratory analysis. This information was used to formulate health risk profiles for all participants who were then counseled on how to decrease identified health risks. Interventions included education about health risks and specific programs which were administered to help modify high-risk behaviors. At one year follow-up, significant risk reductions were reported in many areas of increased risk.Victor W. Acquista, M.D., is a Fellow in General Internal Medicine, Rhode Island Hospital. Tom J. Wachtel, M.D., is Director, Medical Primary Care Unit, Rhode Island Hospital, and Assistant Professor of Community Health, Brown University. Celia I. Gomes, M.P.H., is Health Education Coordinator, Blue Cross/Blue Shield of Rhode Island. Michael Salzillo, M.S., is Team Leader, Statistical Analysis Department, Blue Cross/Blue Shield of Rhode Island. Melanie Stockman, R.N., is Director of Ambulatory Nursing, Rhode Island Hospital.     

Biotransformation of caffeine, paraxanthine, theobromine and theophylline by cDNA-expressed human CYP1A2 and CYP2E1.

Six human cytochrome P450s expressed in HepG2 cells using vaccinia virus cDNA-directed expression, were used to study the biotransformation of caffeine and its metabolites. CYP1A2 alone was responsible for caffeine 3-demethylation and paraxanthine 7-demethylation; in addition, 1A2 catalysed virtually all reactions related to caffeine and its metabolites. The metabolic profile of caffeine biotransformation by CYP1A2 averaged 81.5% for paraxanthine, 10.8% for theobromine and 5.4% for theophylline formation. It remained quite uniform when caffeine concentrations were varied. The most striking finding was that CYP2E1 (the ethanol-inducible form) had major influences upon caffeine metabolism: in particular, it catalysed the formation of theophylline and theobromine from caffeine. Thus, the in vivo metabolite profiling of caffeine may reveal CYP2E1 activities in addition to the previously documented activities of CYP1A2, polymorphic N-acetyltransferase and xanthine oxidase.