Cellular response to oxidative stress at sulfhydryl group receptor sites on the erythrocyte membrane

Ellman's reagent was used to induce an oxidative stimulus on the exofacial membrane sulfhydryl groups of the human erythrocyte. Thiol-disulfide exchange occurring extracellularly was monitored using resonance Raman spectroscopy, and intracellular changes were observed by 1H spin echo nuclear magnetic resonance spectroscopy of the intact cell. The stimulus caused oxidation and depletion of the glutathione pool, which was followed at higher concentrations of Ellman's reagent by a depletion of intracellular ergothioneine levels. Larger changes are induced intracellularly than would be expected from the stoichiometry of the reaction at the exofacial surface. A mechanism is proposed which links exofacial sulfhydryl receptor sites via the transport proteins to spectrin and glutathione. The consequences for the cellular redox balance of an extracellular stimulus of this type are discussed.

A decade of experience with a clinical pharmacokinetics service

The development, operation, and functions of the pharmacokinetics service at Memorial Medical Center of Long Beach (MMCLB) are described, and the data used to determine the quality and cost-effectiveness of the service are presented. Current functions of the pharmacokinetics service at MMCLB include making brief written comments about the interpretations of serum drug concentrations (SDCs) and oral recommendations to physicians on dosage adjustment; provision of written consultations with dosage recommendations; provision of drug information, education, and research; and development of drug dosing guidelines for the pharmacy and medical staff. During the 10-year existence of this service, costs have been justified on the basis of not only revenue generated by the service (in the form of "drug concentration scheduling" and "drug concentration evaluation" fees charged to patients) but also by cost savings resulting from the prevention of inappropriate, misleading, and potentially dangerous SDCs. An audit conducted in 1986 showed that the policy of having pharmacists schedule the sampling times for SDCs saves about $500,000 annually. Quality assurance has been documented by auditing compliance with and therapeutic effectiveness of dosing guidelines and by working with laboratory personnel to identify and prevent spurious SDC results and assay errors. The methods used by the pharmacokinetics service at MMCLB to document the benefits of the service have been vital in proving both its cost-effectiveness and its positive effect on patient care.

Do only the healthy intend to participate in worksite health promotion?

Few companies or organizations involved in health promotion have addressed the major question of whether they are reaching the employees with the greatest health needs or those who could benefit most from these efforts. The popular view that only individuals who are already physically fit and healthy participate in worksite wellness programs was critically examined. Data from 523 survey respondents at the University of Oregon were analyzed to determine whether employees differed on health-related characteristics and their interest in attending a worksite health promotion program. Comparisons between program participant "intenders" and "nonintenders" revealed that both groups had similar lifestyle habits, preventive health practices, and health status profiles. Significant differences were more related to age and perceptions about their physical and emotional health status. Implications for health risk reduction program planning in the work setting are discussed.

Doxorubicin-induced altered glycolytic patterns in the leukemic cell studied by proton spin echo NMR

1H spin echo NMR of the leukemic cell line J-lll is reported. Phosphorylcholine, phosphorylcreatine, lactate and mobile triglyceride are identified as constituents of the cytosolic pool in the intact and viable cells. The concentration of cells in the NMR tube is high (approx. 10(9) in 0.4 ml) and as a result the available oxygen is restricted, making the NMR experiment a plausible in vitro tumour model in which kinetics in the living cell can be probed in a non-invasive manner. Treatment with pharmacological concentrations of the drug doxorubicin produced immediate enhanced anaerobic glycolysis and eventual cell death.

The use of 1H spin echo NMR and HPLC to confirm doxorubicin induced depletion of glutathione in the intact HeLa cell

The effects of doxorubicin on the cellular biochemistry of the HeLa cell using 1H spin echo nuclear magnetic resonance spectroscopy (NMR) of the intact and viable cell in conjunction with dual wavelength HPLC of cell lysates is reported. Directly dose-related changes were observed in lactate and reduced glutathione concentration. Doxorubicin induces a time-dependent depletion of the cytosolic pool of glutathione and a change in the glycolytic pattern of the cell. The glutathione depletion could be partially reversed by controlled pre-treatment of the cells with N-acetylcysteine and cysteine, the protection being linked to the intracellular concentration of the thiol.

Evidence that the catalytic differences of two structurally homologous forms of cytochrome P-450 relate to their heme environment

Cytochromes P-450 PB3a and PB3b, which appear to be equivalent to forms b and e described by Ryan et al. [Ryan, D.E., Thomas, P.E., & Levin, W. (1982) Arch. Biochem. Biophys. 216, 272-288], have been shown to share 97% sequence homology [Suwa, Y., Mizukami, Y., Sogawa, K., & Fujii-Kuriyama, Y. (1985) J. Biol. Chem. 260, 7980-7984] yet exhibit an intriguing difference in enzymatic activity. Studies to establish the basis for this difference, including a development of the technique of surface-enhanced resonance Raman spectroscopy (SERRS), are reported. Studies on substrate binding, metabolism, and redox properties, as well as SERRS, indicate a significant difference in the heme environment of these two proteins. No significant difference in the interaction of the two proteins with P-450 reductase could be established. However, this interaction appeared sensitive to changes in ionic strength, suggesting ionic interactions are important in the functional coupling of these electron-transport components. A marked variation in the ratio of PB3a to PB3b activity in the metabolism of different substrates, which included a series of structurally similar resorufin analogues, provided further evidence that reductase coupling was not a critical factor. Therefore, the few amino acid differences observed between these proteins indicate sites that may be important in influencing the heme environment of these cytochrome P-450's.

Excellence in the management of clinical pharmacy services

Differences in the management of clinical versus nonclinical pharmaceutical services, unique aspects of managing clinical services, and management challenges for the 1990s are described. In nonclinical practice, pharmacists are located in the central pharmacy and have limited contact with physicians and nurses; managers focus on drug procurement, distribution, and accountability. A clinical program takes pharmacists to the patient's bedside and into more inter-professional contact; the management of a clinical pharmacy service is measured by the benefits received by patients, physicians, and nurses and by the job satisfaction of the pharmacists. Management of a clinical program requires (1) recognition of the potential for drugs to cause harm and commitment to pharmacists' responsibility for ensuring appropriate clinical outcomes, (2) analysis of the hospital and how clinical services can best be provided there, (3) obtaining resources to establish or gain access to a drug information service, (4) developing resources and support for a pharmacokinetics service, (5) for a pharmacokinetics service, (5) designing efficient distribution systems supported by automated applications and an adequate technician staff, (6) developing a pharmacist staff that will gain physicians' and nurses' support for clinical programs, (7) developing an organized approach to keeping staff members up to date on new drugs and technology and assisting them in sharing this knowledge with physicians and nurses, (8) demanding and ensuring the quality of the clinical performance of each pharmacist, (9) documenting and evaluating the cost-effectiveness of services provided, and (10) recruiting and retaining good pharmacists and technicians.(ABSTRACT TRUNCATED AT 250 WORDS)

Spin-echo 1H NMR detected response of ergothioneine to oxidative stress in the intact human erythrocyte

Human erythrocytes were subjected to oxidative stress using arsenicals. The study is a model for thiol-related redox processes observed in the etiology of diseases such as rheumatoid arthritis. Spin-echo NMR spectroscopy of the living cell was used to monitor the cellular biochemistry. Oxidation of glutathione and the first demonstrated response of ergothioneine to a chemical stimulus in a cell were observed. The reversible nature of the ergothioneine response is interpreted as an environmental rather than a chemical change.

A comparison of the free radical scavenging activity of leukotrienes and prostaglandins

The relative reactivity of leukotrienes and prostaglandins to free radicals and the superoxide ion generated by the photo oxidation of dianisidine have been assessed in vitro. Leukotrienes are effective general radical scavengers rather than superoxide scavengers, with the order of effectiveness LTD4 greater than LTC4 greater than LTB4. Prostaglandins are relatively unreactive. It is suggested that this susceptibility to free radical attack may be one reason for the formation of chemotactic agents from leukotrienes rather than prostaglandins and this may be one part of the mode of action of these compounds in chronic inflammation.

Determination of alpha-tocopherolquinone (vitamin E quinone) in human serum, platelets, and red cell membrane samples

A high-performance liquid chromatographic method for the determination of alpha-tocopherolquinone in a few selected biological samples is reported. Samples of human serum, blood platelets, or red cell membranes were saponified and extracted with hexane. A measured aliquot of the extract was evaporated under a stream of nitrogen, and the residue was reconstituted with mobile phase (methanol:water, 98:2) and used directly for liquid chromatography. alpha-Tocopherolquinone was separated on Zorbax C-18 columns (25 cm X 4.6 mm, 5-microns particles) and detected by its absorption at 265 nm. The addition of high levels of base during saponification as well as exposure to fluorescent light results in loss of the quinone. Concentrations of alpha-tocopherolquinone in normal human serum are exceedingly small constituting only 0.02-0.05% of the alpha-tocopherol concentration. The technique is particularly useful in the quantitation of the oxidation of alpha-tocopherol in biological samples under in vitro conditions. For example, incubation of human platelets with diamide or arachidonate resulted in oxidation of alpha-tocopherol and the alpha-tocopherolquinone produced accounted for 11.8 and 30.6%, respectively of the alpha-tocopherol lost.

Surface enhanced resonance Raman scattering as a probe of the spin state of structurally related cytochromes P-450 from rat liver

Surface enhanced resonance Raman scattering (SERRS) was observed from structurally related drug-induced rat liver cytochromes P-450 adsorbed on a silver colloid. Careful control of pH and the sequence of addition of components to the so1 is required to prevent protein denaturation at the surface due to conversion to P-450's biologically inactive form P-420 or haem loss. A low-spin P-450 (PB3a), a mixed low- and high-spin P-450 (PB3b) and a predominantly high-spin P-450 (MC1a) were investigated. Spectra recorded in the 1300-1700 cm-1 frequency region, containing the oxidation state marker v4 at 1375 cm-1 (Fe3+) and spin state markers v10 (1625 cm-1, high-spin; 1633 cm-1, low-spin) and v19 (1575 cm-1, high-spin; 1585 cm-1, low-spin) were used to differentiate between the spin states of the various forms of cytochrome P-450. As well as the established spin state marker bands, the intensity of a band at 1400 cm-1 appeared to depend on the high-spin content. Thus, with this method SERRS from silver colloids can be used to determine spin states of related cytochromes P-450 in dilute solution (10(-8)M) and may be of value in studies of protein-substrate interactions.

Alteration of thiol and superoxide dismutase status in rheumatoid arthritis treated with sulphasalazine

Intracellular thiols (LSH), superoxide dismutase (SOD) and plasma thiols (PSH) are thought to have an important role in the protection of tissues from damage by oxygen-derived free radicals. The change in the levels of activity of these substances in patients with active rheumatoid arthritis treated with sulphasalazine for 6 months was assessed in 22 patients. Over this time there was a marked improvement in disease activity. This was accompanied by an early increase in red cell LSH and decrease in SOD, although by 6 months these changes had completely reversed. In addition the negative correlation between these indices at week 0 had disappeared by week 6. Over the 6 months there was a steady rise in PSH. The change in PSH is slow and is thus more likely to reflect a change in the disease process rather than an active role for the thiol, but the early changes in intracellular parameters may be of importance in the action of this drug. These changes are similar to changes found with other second-line drugs. It is also of interest that a drug which does not itself possess a thiol group is capable of altering the thiol status of cells.

A 1H spin echo NMR study of the HeLa tumour cell

Phosphorylcholine, phosphorylcreatine, lactate, glutathione, glycine and leucine were identified in living HeLa cells in the first study of this cell type by 1H spin echo NMR spectroscopy. The technique has the advantage that it is non-invasive, providing detailed structural information on individual species present in the cell matrix. It has been used in this case to study the rate of energy consumption following the activation of the glycolytic pathway with glucose.

Early and late changes in sulphydryl group and copper protein concentrations and activities during drug treatment with aurothiomalate and auranofin

Superoxide dismutase activity (SOD), plasma and lysate thiol concentrations (PSH and LSH), and caeruloplasmin oxidase activity (CP) reflect the underlying reduction-oxidation imbalance associated with rheumatoid arthritis (RA), and are believed to be involved in the protection of the cell against free radical activity. The early and late changes in these parameters have been observed and compared with standard clinical and biochemical assessments of disease activity in 90 patients with active RA, randomly assigned to receive either sodium aurothiomalate, auranofin, or auranofin placebo. An index based on clinical criteria was used to identify patients as responders or non-responders after 24 weeks of therapy. In the first six weeks of treatment a change in SOD activity and LSH concentration in a direction away from controls was followed by a return towards control levels in responders only. This suggests that in RA evidence of clinical improvement induced by gold drugs is preceded by an initial biochemical response in an inflammatory direction. The extracellular parameters PSH and CP did not show the same early response, but PSH levels in responders showed a slower change towards normal values, though at no time were values obtained that might suggest a complete remission. Thus the intracellular parameters appear to reflect an early effect of the drugs on cells which may possibly be of use in predicting the outcome of therapy, whereas the extracellular parameters provide confirmatory evidence for an eventual improvement.

Changes in glutathione in intact erythrocytes during incubation with penicillamine as detected by 1H spin-echo NMR spectroscopy

1H spin-echo NMR spectroscopy was used to study changes in glutathione status in intact erythrocytes. The concentration of glutathione in suspensions of erythrocytes in 2H2O saline is significantly different in cells from patients with rheumatoid arthritis than in controls from normal healthy volunteers. It is observed that the methods of separation and suspension affect lactate metabolism in red cells. Incubation of erythrocytes with solutions of the therapeutic agent D-penicillamine in 2H2O saline produced a change in glutathione resonances which is indicative of an increase in diglutathione concentration. Signals from the methyl groups of penicillamine decreased at a commensurate rate. Incubation of normal cells with plasma from patients with rheumatoid arthritis who had the same blood group as the normal volunteer indicated a much larger fall in glutathione signal with plasma from a patient treated with penicillamine than from a patient on non-steroidal anti-inflammatories.

Ethical, economic, and professional issues in home health care

Important ethical, economic, and professional issues in home health care (HHC) are identified and discussed. Patient services issues in HHC involve the ethics of providing high-technology feeding therapies to terminally ill patients and the controversies surrounding drug products, such as the appropriate amount of drug to be dispensed, the appropriate individual to compound home-care drug products, acceptable types of product packaging, and the impact of a switch in venders on the drug products supplied to patients. Economic issues include reasonable profit for HHC services, methods used to charge for products and services, payments to physicians for patient referrals, and pharmacies owned and operated by the HHC industry. Pharmacy relations issues center on the influence of nonpharmacists on pharmacy-based HHC services and the effect of HHC services on intraprofessional relations. How pharmacists resolve the many ethical, economic, and professional issues in HHC will determine the quality of services provided to patients, the nature of the working relationships between pharmacists and other health professionals, and the direction that pharmacy HHC services will take in the future.

Implications of the new technology for pharmacy education and practice

Educators and practitioners in the health professions are faced with two questions as they attempt to adapt to changes brought by new technology. What is the nature of the technology? and What are the implications for education and practice? The present paper directs these questions to pharmacy in a three-part discussion: the implications of the technology; the relevant technology presented as brief, descriptive vignettes; and comments on the apparent problems which are created by technological change. The implications are presented first, as a set of general guidelines, second, the implications for the knowledge and skill components of education and practice, and third, as attitudes required by pharmacists and pharmacy students. The paper concludes with a list of still unanswered questions relative to the future.

Implications of new technology for pharmacy education and practice

Specific knowledge and skills needed by pharmacists in an era of advancing health-care technology are presented, and the most important modern technologic developments in health care are described briefly. Implementation of new technology in health care will be affected by cost considerations and by social trends such as shifting population demographics, an increase in diseases of lifestyle, consumerism, and self-care. Technologic advances in the following areas are described: computerized information networks, bioelectronics, biotechnology, computer graphics, diagnostic imaging, and drug development in space and in the oceans. Diseases are noted for which diagnosis and treatment using new technology is promising. The roles of interferon and monoclonal antibodies are described, and trends in development of new drugs and drug delivery systems are traced. A new philosophical basis for pharmacy education that is consistent with the needs of a technologically oriented society is needed. Practitioners will look to their professional societies for assistance in identifying and implementing the new technology.

Electroconvulsive therapy: a Canadian perspective

Recent ECT practices in Canada are reviewed from a historical perspective with respect to specific criticisms. Utilization is decreasing; utilization rates vary widely between Provinces and between regions; disproportionate numbers of females have been receiving ECT; a substantial group of patients diagnosed as neurotic and schizophrenic continue to receive ECT; criteria and guidelines for its use are not consistently applied. Expected rates of ECT used are estimated, based on theory and practice as well as on published data on the epidemiology of affective disorders. Data on actual Canadian usage are reviewed and compared with an estimated minimum ratio of 30-45+ cases per year of non bi-polar depression per 100,000 population requiring ECT. Results show that there may be a substantial number of patients in some Provinces for whom ECT is the best available treatment and who are not receiving it. There is some ethical concern associated with possible under-use of ECT as the best therapy available for certain patient groups. Clinical cases and patterns of care should be reviewed at the hospital level to determine how best to effect improvements in the use of this treatment.

Effect of an automated bedside dispensing machine on medication errors

The effect of an automated bedside dispensing machine on medication errors was studied on a 32-bed surgical unit of an 848-bed hospital. The experimental system (McLaughlin Dispensing System) included at each patient's bedside a locked medication cabinet that was electronically programmed to allow the nurse access to doses due at a particular time. The control system was a decentralized unit dose system. A crossover study design with random assignment of subjects and treatments was used. In the 14-day study period, nurses were observed by a pharmacist for 28 five-hour periods as they administered medications on the day and evening shifts. The mean error rates were significantly different--10.6% for the experimental system and 15.9% for the control system. Wrong time errors were the most common type. No significant differences were found between day and evening shifts or workloads of individual nurses. There was no treatment order effect. The error rate was significantly lower for the automated dispensing system than for the system using unit doses dispensed from a satellite pharmacy. Automated dispensing systems may be useful in reducing errors in administration time and dose omissions.