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Thermus sp. strain Rt41A produces an extracellular thermostable alkaline proteinase. The enzyme has a high isoelectric point (10.25-10.5) which can be exploited in purification by using cation-exchange chromatography. The proteinase was purified to homogeneity and has a molecular mass of 32.5 kDa by SDS/PAGE. It is a glycoprotein, containing 0.7% carbohydrate as glucose equivalents, and has four half-cystine residues present as two disulphide bonds. Maximum proteolytic activity was observed at pH 8.0 against azocasein and greater than 75% of this activity was retained in the pH range 7.0-10.0. Substrate inhibition was observed with casein and azocasein. The enzyme was stable in the pH range 5.0-10.0 and maximum activity, in a 10-min assay, was observed at 90 degrees C with 5 mM CaCl2 present. No loss of activity was observed after 24 h at 70 degrees C and the half-lives at 80 degrees C and 90 degrees C were 13.5 h and 20 min, respectively. Removal of Ca2+ reduced the temperature for maximum proteolytic activity against azocasein to 60 degrees C and the half-life at 70 degrees C was 2.85 min. The enzyme was stable at low and high ionic strength and in the presence of denaturing reagents and organic solvents. Rt41A proteinase cleaved a number of synthetic amino acid p-nitrophenol esters, the kinetic data indicating that small aliphatic or aromatic amino acids were the preferred residue at the P1 position. The kinetic data for the hydrolysis of a number of peptide p-nitroanilide substrates are also reported. Primary cleavage of the oxidized insulin B chain occurred at sites where the P1' amino acid was aromatic. Minor cleavage sites (24 h incubation) were for amino acids with aliphatic side chains at the P1' position. The esterase and insulin cleavage data indicate the specificity is similar for both the P1 and P1' sites.

The potential of proteolytic enzymes from extremely thermophilic eubacteria to clear ultrafiltration membranes fouled during the processing of whey was investigated. The enzymes were initially tested for their ability to hydrolyse freeze-dried preparations of material removed from fouled ultrafiltration membranes. Under the conditions used, the serine proteinases from Thermus strains were more efficient than the metalloproteinase from Bacillus strain EA.1, and were subsequently investigated for their ability to clear fouled membrane discs using purpose-built laboratory scale equipment. The proteinase from Thermus strain Rt4.1A proved most effective and gave a linear increase of water flux with time when used to treat fouled membranes at 70°C. The rate of clearing and final flux levels obtained using enzyme alone were lower than those obtained using alkaline-EDTA. The performance of the enzyme was, however, synergistically enhanced using the anionic detergent sodium dodecyl sulphate in combination with the enzyme.

Experimental data show that the effect of temperature on enzymes cannot be adequately explained in terms of a two-state model based on increases in activity and denaturation. The Equilibrium Model provides a quantitative explanation of enzyme thermal behaviour under reaction conditions by introducing an inactive (but not denatured) intermediate in rapid equilibrium with the active form. The temperature midpoint (Teq) of the rapid equilibration between the two forms is related to the growth temperature of the organism, and the enthalpy of the equilibrium (ΔHeq) to its ability to function over various temperature ranges. In the present study, we show that the difference between the active and inactive forms is at the enzyme active site. The results reveal an apparently universal mechanism, independent of enzyme reaction or structure, based at or near the active site, by which enzymes lose activity as temperature rises, as opposed to denaturation which is global. Results show that activity losses below Teq may lead to significant errors in the determination of ΔG*cat made on the basis of the two-state (‘Classical’) model, and the measured kcat will then not be a true indication of an enzyme's catalytic power. Overall, the results provide a molecular rationale for observations that the active site tends to be more flexible than the enzyme as a whole, and that activity losses precede denaturation, and provide a general explanation in molecular terms for the effect of temperature on enzyme activity.

Making Myelin The myelin sheath insulates neurons and facilitates rapid axonal conduction, and its disruption is characteristic of some neurological disorders, such as multiple sclerosis. Axonal signals stimulate Schwann cells to form myelin in peripheral nerves, but the mechanism is not completely known. By characterizing a mutation identified in zebrafish, Monk et al. (p. 1402 ; see the Perspective by Meijer ) show that Gpr126, a member of the G protein–coupled receptor superfamily, is essential for myelin formation. It appears that Gpr126 acts as a receptor for axonal signals to elevate cAMP levels in Schwann cells and trigger myelination.

Ablation of the cellular prion protein PrP(C) leads to a chronic demyelinating polyneuropathy affecting Schwann cells. Neuron-restricted expression of PrP(C) prevents the disease, suggesting that PrP(C) acts in trans through an unidentified Schwann cell receptor. Here we show that the cAMP concentration in sciatic nerves from PrP(C)-deficient mice is reduced, suggesting that PrP(C) acts via a G protein-coupled receptor (GPCR). The amino-terminal flexible tail (residues 23-120) of PrP(C) triggered a concentration-dependent increase in cAMP in primary Schwann cells, in the Schwann cell line SW10, and in HEK293T cells overexpressing the GPCR Adgrg6 (also known as Gpr126). By contrast, naive HEK293T cells and HEK293T cells expressing several other GPCRs did not react to the flexible tail, and ablation of Gpr126 from SW10 cells abolished the flexible tail-induced cAMP response. The flexible tail contains a polycationic cluster (KKRPKPG) similar to the GPRGKPG motif of the Gpr126 agonist type-IV collagen. A KKRPKPG-containing PrPC-derived peptide (FT(23-50)) sufficed to induce a Gpr126-dependent cAMP response in cells and mice, and improved myelination in hypomorphic gpr126 mutant zebrafish (Danio rerio). Substitution of the cationic residues with alanines abolished the biological activity of both FT(23-50) and the equivalent type-IV collagen peptide. We conclude that PrP(C) promotes myelin homeostasis through flexible tail-mediated Gpr126 agonism. As well as clarifying the physiological role of PrP(C), these observations are relevant to the pathogenesis of demyelinating polyneuropathies--common debilitating diseases for which there are limited therapeutic options.

Purpose. The extent of didactic and laboratory instruction related to compounded sterile preparations (CSPs) provided by U.S. schools of pharmacy was studied. Methods. A nine-item survey was developed and mailed to the deans of 82 U.S. schools of pharmacy in 2005. The survey instrument was designed to gather basic demographic information about the school of pharmacy, identify availability and characteristics of instruction offered on the compounding of sterile preparations, identify which of 20 topics were covered in either a didactic or laboratory setting, determine how students’ skills in sterile preparation were assessed, and identify the compounding environment at the school of pharmacy. Data were analyzed using descriptive statistics. Results. A total of 53 surveys were returned, yielding a response rate of 65%. All schools included some instruction on CSPs; however, only 70% required students to compound on their own (rather than in groups or not at all), and only 21% offered a standalone course on this topic. Most schools (88%) taught students about U.S. Pharmacopeia chapter 797 standards for sterile compounding. Only 13% of schools felt that their students had adequate training in compounding sterile preparations before graduation; however, most (88.7%) believed that students could only become fully competent in these skills over time in actual practice. Conclusion. A survey sent to deans of pharmacy schools revealed that instruction provided to pharmacy students in preparing CSPs varied widely. Only about a sixth of respondents believed that their students were adequately trained in compounding sterile preparations before graduation.

Expression of the human epidermal growth factor receptor (EGFR) in murine Schwann cells results in loss of axon–Schwann cell interactions and collagen deposition, modeling peripheral nerve response to injury and tumorigenesis. Mast cells infiltrate nerves in all three situations. We show that mast cells are present in normal mouse peripheral nerve beginning at 4 weeks of age, and that the number of mast-cells in EGFR+ nerves increases abruptly at 5–6 weeks of age as axons and Schwann cells dissociate. The increase in mast cell number is preceded and accompanied by elevated levels of mRNAs encoding the mast-cell chemoattractants Rantes, SCF and VEGF. Genetic ablation of mast cells and bone marrow reconstitution in W41 × EGFR+ mice indicate a role for mast cells in loss of axon−Schwann cell interactions and collagen deposition. Pharmacological stabilization of mast cells by disodium cromoglycate administration to EGFR+ mice also diminished loss of axon−Schwann cell interaction. Together these three lines of evidence support the hypothesis that mast cells can contribute to alterations in peripheral nerves.

To describe the extent of psychiatric pharmacy instruction in US pharmacy curricula, including course and faculty characteristics and mental health topics taught in clinical therapeutics-based courses.An 11-item survey instrument (54% response) was developed and mailed to 91 colleges and schools of pharmacy.Over 75% of colleges and schools employed a psychiatric pharmacist; however, less than 50% of faculty teaching psychiatric pharmacy content were psychiatric pharmacy specialists as defined in the study. All colleges and schools included psychiatric topics as part of a therapeutics-based course with an average of 9.5% of course content devoted to these topics. About 25% of colleges and schools offered elective didactic courses in psychiatric pharmacy. Only 2 schools required a psychiatric pharmacy advanced pharmacy practice experience (APPE), but about 92% offered elective APPEs. The mean number of hours spent on lecture- and case-based instruction across all colleges and schools was highest for depression and lowest for personality disorders.There is a need for colleges and schools of pharmacy to better identify and standardize the minimal acceptable level of didactic instruction in psychiatric pharmacy as well as the minimal level of specialty qualifications for faculty members who teach this subject.

CD4+CD25+Foxp3+ regulatory T cells (Tregs) contribute to the maintenance of peripheral tolerance by inhibiting the expansion and function of conventional T cells. Treg development and homeostasis are regulated by the Ag receptor, costimulatory receptors such as CD28 and CTLA-4, and cytokines such as IL-2, IL-10, and TGF-β. Here we show that the proportions of Tregs in the spleen and lymph nodes of mice with inactive p110δ PI3K (p110δD910A/D910A) are reduced despite enhanced Treg selection in the thymus. p110δD910A/D910A CD4+CD25+Foxp3+ Tregs showed attenuated suppressor function in vitro and failed to secrete IL-10. In adoptive transfer experiments, p110δD910A/D910A T cells failed to protect against experimental colitis. The identification of p110δ as an intracellular signaling protein that regulates the activity of CD4+CD25+Foxp3+ Tregs may facilitate the further elucidation of the molecular mechanisms responsible for Treg-mediated suppression.

Benign peripheral nerve tumors called neurofibromas are a major source of morbidity for patients with neurofibromatosis type 1. Some neurofibroma Schwann cells aberrantly express the epidermal growth factor receptor (EGFR). In a mouse model in which the CNPase promoter drives expression of human EGFR in Schwann cells, nerves develop hypertrophy, mast cell accumulation, collagen deposition, disruption of axon-glial interactions, characteristics of neurofibroma and are hypoalgesic. Administration of the EGFR antagonist cetuximab (IMC-C225) for 2 weeks beginning at birth in CNPase-hEGFR mice normalized all pathologies at 3 months of age as evaluated by hotplate testing or histology and by electron microscopy. Mast cell chemoattractants brain-derived neurotrophic factor, monocyte chemoattractant protein-1, and transforming growth factor-β1, which may account for mast cell accumulation and fibrosis, were reduced by cetuximab. Later treatment was much less effective. A birth to 2-week pulse of cetuximab blocked hEGFR phosphorylation and Schwann cell proliferation in perinatal mutant nerve, so CNPase-hEGFR Schwann cell numbers correlate with the cetuximab effect. A >250-fold enlarged population of EGFR + /p75 + cells was detected in newborn Nf1 +/− mouse nerves. These results suggest the existence of an EGFR + cell enriched in the perinatal period capable of driving complex changes characteristic of neurofibroma formation.

In this paper we describe construction of a luciferase-based vector, pPL2 lux , and use of this vector to study gene expression in Listeria monocytogenes . pPL2 lux is a derivative of the listerial integration vector pPL2 and harbors a synthetic luxABCDE operon encoding a fatty acid reductase complex (LuxCDE) involved in synthesis of the fatty aldehyde substrate for the bioluminescence reaction catalyzed by the LuxAB luciferase. We constructed pPL2 lux derivatives in which the secA and hlyA promoters were translationally fused to luxABCDE and integrated as a single copy into the chromosome of L. monocytogenes EGD-e. Growth experiments revealed that hlyA was expressed predominantly in the stationary phase in LB medium buffered at pH 7.4, whereas secA expression could be detected in the exponential growth phase. Moreover, the correlation between luciferase activity and transcription levels, as determined by reverse transcriptase PCR, was confirmed using conditions known to lead to repression and activation of hemolysin expression (addition of cellobiose and activated charcoal, respectively). Furthermore, hemolysin expression could be monitored in real time during invasion of an intact monolayer of C2Bbe1 (Caco-2-derived) cells. Finally, hemolysin expression could be detected in the livers, spleens, and kidneys of mice 3 days postinfection. These experiments clearly established the effectiveness of pPL2 lux as a quantitative reporter system for real-time, noninvasive evaluation of gene expression in L. monocytogenes .

Objective To investigate the hypothesis that loss of suppression mediated by peripheral CD4+,CD25+ regulatory T cells is a hallmark of systemic lupus erythematosus (SLE). Methods Mice of the MRL/Mp strain were studied as a polygenic model of SLE. Following immunomagnetic selection, peripheral lymphoid CD25+ and CD25− CD4+ T cells were cultured independently or together in the presence of anti-CD3/CD28 monoclonal antibody–coated beads. Proliferation was assessed by measuring the incorporation of tritiated thymidine. Results While MRL/Mp CD4+,CD25+ regulatory T cells showed only subtle abnormalities of regulatory function in vitro, syngeneic CD4+,CD25− T cells showed significantly reduced sensitivity to suppression, as determined by crossover experiments in which MRL/Mp CD4+,CD25− T cells were cultured with H-2–matched CBA/Ca CD4+,CD25+ regulatory T cells in the presence of a polyclonal stimulus. Conclusion Our findings highlight a novel defect of peripheral tolerance in SLE. Identification of this defect could open new opportunities for therapeutic intervention.

It has been generally accepted that enzyme activity requires a minimal hydration of about 0.2 g H2O g(-1) protein. This fits well with evidence that hydration above this level is associated with the onset of intramolecular motions. The influence of enzyme hydration on the hydrolysis of substrate by Candida rugosa Lipase B and pig liver esterase was investigated. Each enzyme was studied as a powder at various hydration levels, using vapour phase ethyl butyrate as substrate. This procedure allows the separation of those effects that are due to hydration from those arising from diffusional constraints. We found hydrolytic activity in both enzymes at all hydration levels above zero (between 0.054-0.47 and 0.029-0.60 g H2O g(-1) protein, respectively) that were investigated. The lowest hydration level investigated

Benign neurofibromas and malignant peripheral nerve sheath tumors are serious complications of neurofibromatosis type 1. The epidermal growth factor receptor is not expressed by normal Schwann cells, yet is overexpressed in subpopulations of Nf1 mutant Schwann cells. We evaluated the role of EGFR in Schwann cell tumorigenesis. Expression of EGFR in transgenic mouse Schwann cells elicited features of neurofibromas: Schwann cell hyperplasia, excess collagen, mast cell accumulation, and progressive dissociation of non-myelin-forming Schwann cells from axons. Mating EGFR transgenic mice to Nf1 hemizygotes did not enhance this phenotype. Genetic reduction of EGFR in Nf1+/−;p53+/− mice that develop sarcomas significantly improved survival. Thus, gain- and loss-of-function experiments support the relevance of EGFR to peripheral nerve tumor formation.

Adhesion G protein-coupled receptors (aGPCRs) comprise the second largest yet least studied class of the GPCR superfamily. aGPCRs are involved in many developmental processes, immune and synaptic functions, but the mode of their signal transduction is unclear. Here, we show that a short peptide sequence (termed the Stachel sequence) within the ectodomain of two aGPCRs, GPR126 and GPR133, functions as a tethered agonist. Upon structural changes within the receptor ectodomain, this intramolecular agonist is exposed to the 7-transmembrane helix domain, which triggers G-protein activation. Our studies show high specificity of a given Stachel sequence for its receptor. Finally, the function of Gpr126 is abrogated in zebrafish with a mutated Stachel sequence, and signaling is restored in hypomorphic gpr126 zebrafish mutants upon exogenous Stachel peptide application. These findings illuminate a previously unknown mode of aGPCR activation, and can initiate the development of specific ligands for this currently untargeted GPCR family.

Treatment for prostatic adenocarcinoma is reliant on the initial androgen dependence of this tumor type. The goal of therapy is to eliminate androgen receptor activity, either through direct inhibition of the receptor or through inhibition of androgen synthesis. Although this course of therapy is initially effective, androgen-refractory tumors ultimately arise and lead to patient morbidity. Factors contributing to the transition from a state of androgen dependence to the androgen-refractory state are poorly understood, but clinical evidence in androgen-refractory tumors suggests that the androgen receptor is inappropriately activated in these cells. Thus, the mechanisms that contribute to inappropriate (androgen-independent) activation of the androgen receptor (AR) is an area of intensive research. Here we demonstrate that bisphenol A (BPA), a polycarbonate plastic monomer and established xenoestrogen, initiates androgen-independent proliferation in human prostatic adenocarcinoma (LNCaP) cells. The mitogenic capacity of BPA occurred in the nanomolar range, indicating that little BPA is required to stimulate proliferation. We show that BPA stimulated nuclear translocation of the tumor-derived receptor (AR-T877A), albeit with delayed kinetics compared with dihydrotestosterone. This translocation event was followed by specific DNA binding at androgen response elements, as shown by electrophoretic mobility shift assays. Moreover, the ability of BPA to stimulate AR-T877A activity was demonstrated by reporter assays and by analysis of an endogenous AR target gene, prostate-specific antigen. Thus, BPA is able to activate AR-T877A in the absence of androgens. Lastly, full mitogenic function of BPA is dependent on activation of the tumor-derived AR-T877A. These data implicate BPA as an inappropriate mitogen for prostatic adenocarcinoma cells and provide the impetus to study the consequence of BPA exposure on prostate cancer.

Aims: To determine the effect of chlorine on mixed bacterial biofilms on stainless steel (SS) and conveyor belt surfaces. Methods and Results: Biofilms were exposed to pH-adjusted (6AE5) and non-pH-adjusted solutions of chlorine (200, 400 and 600 ppm) for either 2, 10 or 20 min and survivors enumerated. There were significant differences in cell death relating to chlorine concentration and exposure time for the cells attached to the SS, with solutions adjusted to pH 6AE5 being more effective at reducing numbers. In contrast, on conveyor belt surfaces cell numbers decreased by less than two logs after 20 min regardless of treatment. Conclusions: Chlorine effectiveness is dependent on its concentration, solution pH, exposure time, the nature of the surface and the microbial species present. Significance and Impact of Study: In the interests of food safety it is important that sanitizer users are aware of the conditions that effect their performance.

Objectives To evaluate financial terms and legal wording in insurance contracts and negotiate their terms with companies to improve an independent pharmacy's financial position and to determine the time required to negotiate a contract and translate that time into a salary cost. Setting An independent pharmacy in a small town in Alabama with a population of approximately 6,000. Practice Description The prescription department accounts for two-thirds of the pharmacy's sales and dispenses approximately 70,000 prescriptions each year. Insurance companies paid for over 59% of these prescriptions in 2000. The pharmacy is open 7 days a week with one full-time pharmacist and a second pharmacist who works 2 days a month. Practice Innovation A contract negotiation form was developed that addressed factors that might affect a pharmacy's decision to accept or reject a contract; the form included an area for recording the time involved in negotiating each contract. Interventions Insurance companies selected by the pharmacy owner were faxed copies of an Insurer Demographics Collection Form. Upon collection of all data and finalization of proposed changes, a copy of the contract with the proposed changes marked, along with a letter explaining and justifying the changes, was sent to the insurance company. If no response was received from the company, the contact person was called and negotiations proceeded over the telephone. Main Outcome Measures Primary end points were the percentage of companies that would negotiate and the average increase in reimbursement achieved. Secondary end points included the time involved in negotiations and the translation of that time into a salary cost. Results None of the nine participating companies accepted any of the changes proposed. The time to negotiate each contract ranged from 28 minutes to 74 minutes, taking an average of 48.4 minutes. Depending on the division of work between the pharmacist and the technician, the salary cost for the negotiations ranged from $14.68 to $18.73 per contract. Conclusion This study provides a realistic description of attempts at contract negotiation between one pharmacy and nine third party payers. The difficulty of achieving successful results and the necessity of carefully considering the time and cost of contract negotiations underscore how important it is for independent pharmacists to concentrate their efforts on contracts and terms they have an opportunity to change.

The reasons for time clock use in health-care institutions, the categories of workers required to use a time clock and other timekeeping methods, and the incidence of time-clock-related conflicts were studied. A questionnaire was mailed to a random sample of 565 hospitals in October 1989. Usable responses were received from 340 (60.0%) of the institutions. Reasons given for time clock use included payroll tabulation, overtime calculation, and ensuring fair payment. Thirty-four institutions (10.0%) required all employees to clock in, and 179 (52.6%) required some employees to do so. A written time card completed by the employee was the method used most frequently if a time clock was not used. Clinical pharmacists were required to clock in at 51 institutions (15.0%), staff pharmacists at 62 (18.2%), and pharmacy technicians at 144 (42.9%). Clinical nurse specialists and registered nurses clocked in at 88 (25.9%) and 169 (49.7%) hospitals, respectively, and licensed practical nurses and nurse's aides each clocked in at 176 hospitals (51.8%). Less than 6% of the hospitals required salaried pharmacists or nurses to use a time clock. Of the respondents, 152 (44.7%) reported that they were not aware of any conflicts or that no conflicts had been experienced. Inconvenience and inaccurate clocking were the most common sources of conflict cited. Most hospitals use time clocks for nonsalaried employees for bookkeeping purposes; dissatisfaction with this method of tracking hours worked does not appear to be widespread.

Medicare legislation stimulated the development of home care services but also resulted in fragmentation of service components. In the 1980s, prospective pricing and diagnosis-related groups, and resulting pressures to reduce inpatient length of stay, prompted additional growth of the industry. Even so, in 1995 home care represented only 3% of total national expenditures on health care. The annual growth rate of the home infusion industry dropped from 64% in 1982-86 to 24% in 1986-93. While revenue per patient for home infusion is expected to decrease under managed care, an increasing number of patients will support continued market growth. The home infusion market is highly competitive, with only a few large national providers and many small local providers. In 1996, 29% of acute care hospitals provided or were developing a home care program. Community pharmacists' options in the home infusion area include independent services, partnerships, joint ventures, contracts with hospitals, and franchises. The home infusion market is being integrated into alternative sites, such as ambulatory infusion centers (AICs), as providers attempt to diversify to maintain managed care contracts. AICs provide infusion therapy and nursing to noninstitutionalized, nonhome-bound patients. Untapped sources for future growth of the infusion market include long-term-care facilities. More consistent studies of the home care market are needed. Despite slowed growth in recent years, home care has a strong market in the United States.

JET was extensively modified in the 1992/93 shutdown. The new pumped divertor and many new systems were brought into operation early in 1994. Operations have progressed to 4MA plasma current and, with substantial additional heating, H-mode confinement results confirm the expected scaling. The high power handling capability of the pumped divertor with sweeping is estimated at 20MW for 20s. H-mode plasmas have large Type I ELMs. With lower hybrid heating alone, 2MA full current drive has been achieved with good efficiency, with ICRF power, effective heating and direct electron heating have been demonstrated.

The JET tokamak has been fitted with a new glow discharge cleaning system. Four electrodes of a novel design, offer the following advantages over their predecessors: they do not need water cooling and they do not take up significant port space. Results are presented for the initial use of these electrodes including current density distribution and impurity removal rate.

To the Editor. An ideal examination system determines approaches to both teaching (what and how teachers teach) and learning (what students learn).1,2 Apart from student assessment, examinations help teachers modify their teaching methodologies or adopt new ones to impart the desired academic outcomes. A fair and uniform examination process is important, but many attempts to standardize the process remained fruitless until the late 1990s when the Pakistani government began reforming the examination process. Stringent measures were imposed, and some success was achieved to bring uniformity and eradicate malpractices in the examination system, especially at secondary and higher secondary levels.3,4 Thus far, there is no report of such attempts at reforming the examination system at the graduate and postgraduate levels. The same problems were encountered while reviewing the pharmacy examination system in Pakistani institutes. At present, a number of pharmacy institutes in both public and private sectors are practicing 2 types of examination systems – semester and annual. The mode of assessment is different in these 2 systems and is causing uneven academic outcomes. Surprisingly, different institutes practicing the same system are not uniform in terms of grading, which can deprive capable students of obtaining jobs since in government and the private sector, candidates are short-listed based on their grades in pharmacy school. Hence, there is a real need to standardize the examination system in all pharmacy institutes of Pakistan. In comparing semester and annual grading systems, the former is found to be easier, less time-consuming, and more economical; however, the sole internal assessment is making the fairness of this system hazy due to a higher probability of malpractices by examiners themselves, or because of the influence of students, parents, politicians, and institutional heads. Inconsistency is most problematic in the private sector where teachers often try to remain in good favor with their students by showing leniency in evaluation, and in good stead with the administration of the institutes by showing good results. In the annual evaluation system, assessment is conducted externally for the theoretical examination and internally for the practical examination. While this system seems fair, in fact it raises serious concerns including the methods used to appoint the external examiners, the non-standardized grading system used, and the cost and inefficiency of the system. Students often are concerned and inquisitive about the grading criterion used (eg, why they received a grade of 50% to 60% on a question they attempted to answer completely) and delays in receiving their grades. These are sensitive areas requiring the focus of academicians and authorities controlling the examination process. The methods of administering and grading practical examinations are also ambiguous and un-standardized. The process is conducted by 1 external and 4 internal examiners in a strange way because there are no standardized examination equations. This is worth noting in the case of viva, a part of the practical examination, in which more consideration is given to theory and not just practical aspects. This part of the examination is one of the most un-standardized parts in terms of the types of questions given, the number of questions per student, the grading scheme per question, and the number of examiners and their approach to grading. The practical examination is also given at different times, which adds another variable. Unlike theoretical examinations, the record of viva assessment is not maintained professionally so students are not able to check their paper if they are not satisfied with the evaluation. If students are not satisfied with the evaluation they may check their paper. Students often fear viva assessments, complaining of less time to review the syllabus and the evaluation process. After the examination, they remain uncertain until grades are posted. In one of the universities where only students with the highest grades are admitted, the failure rate is more than 60%, and those who pass have marks in the range of only 50%-60%. The newspaper The Daily Dawn has reported that students fear examinations, and upon failing, some have committed suicide.5 It is a serious concern because students are blaming the higher failure rate on 2 things: the monetary benefits that the examiners receive for conducting supplementary examinations, and the university's desire to keep students submissive. There is no official/unofficial body to analyze and correct these problems with examinations, which is an important matter to academia not only for improving teaching and learning but also to produce professionally and psychologically sound pharmacists to serve humanity.

A comprehensive bibliography on home intravenous therapy is presented for use in developing a home health care pharmacy practice. Over 500 references representing 26 topics relevant to home care are included. Advantages of the bibliography over current on-line computer programs are discussed as are the limitations of this type of resource.

To compare the effectiveness of two routinely used methods of preoxygenation in protecting against hypoxia in the elderly, the arterial O2 saturation was measured using an oximeter. Twenty-four elderly patients (greater than or equal to 65 yr) presenting for elective orthopedic surgery were randomly allocated to receive either 3-min or four-maximal-breaths of 100% O2 via a Bain circuit. After preoxygenation, anesthesia was induced, tracheal intubation performed with patients kept apneic, and the endotracheal tube left open to air. The arterial O2 saturation was measured before preoxygenation and continually recorded during desaturation. Although attaining similar arterial O2 saturation values after preoxygenation, patients in the four-maximal-breath group had significantly shorter times (P less than 0.0001) to all levels of desaturation. We suggest that preoxygenation with 3-min breathing of 100% O2 offers more protection against hypoxia due to prolonged apnea after induction of anesthesia in the elderly than does four maximal breaths of 100% O2.

The reasons for time clock use in health-care institutions, the categories of workers required to use a time clock and other timekeeping methods, and the incidence of time-clock-related conflicts were studied. A questionnaire was mailed to a random sample of 565 hospitals in October 1989. Usable responses were received from 340 (60.0%) of the institutions. Reasons given for time clock use included payroll tabulation, overtime calculation, and ensuring fair payment. Thirty-four institutions (10.0%) required all employees to clock in, and 179 (52.6%) required some employees to do so. A written time card completed by the employee was the method used most frequently if a time clock was not used. Clinical pharmacists were required to clock in at 51 institutions (15.0%), staff pharmacists at 62 (18.2%), and pharmacy technicians at 144 (42.9%). Clinical nurse specialists and registered nurses clocked in at 88 (25.9%) and 169 (49.7%) hospitals, respectively, and licensed practical nurses and nurse's aides each clocked in at 176 hospitals (51.8%). Less than 6% of the hospitals required salaried pharmacists or nurses to use a time clock. Of the respondents, 152 (44.7%) reported that they were not aware of any conflicts or that no conflicts had been experienced. Inconvenience and inaccurate clocking were the most common sources of conflict cited. Most hospitals use time clocks for nonsalaried employees for bookkeeping purposes; dissatisfaction with this method of tracking hours worked does not appear to be widespread.

Objectives. The purpose of this paper is to describe the use of personal digital assistants (PDAs) in a pharmacy school during the first year in which the tool was provided to all students and faculty members. Methods. A survey was developed and administered to students in each year of the curriculum and to full-time faculty members. Data were evaluated using descriptive statistics. Results. After providing PDAs, we observed that use of the devices was high by students (95.2%) and faculty members (93.3%). For approximately one third of the survey responders, use of pharmacy-related applications accounted for over 50% of usage time, although use varied according to individual courses. Conclusions. A high percentage of faculty members and students used the PDA provided to them by the school. Although PDA use across the curriculum has varied, the tool was viewed as having a positive impact on student learning.

Summary The reactions of two fulvic acid samples with Cu2+ and Cd2+ have been studied by potentiometric titration (pH and ion selective electrode). The metal-uptake curves for samples initially rendered ‘metal-free’ by a precipitation-solvent extraction technique resemble those for citric and malic acids at soil pH (4–6.5). The presence of aliphatic and aromatic components was established by 13C nmr spectroscopy; the presence of phenolic components was inferred from pH titrations. It is shown that a polycarboxylate component (simulated by citrate) would mask reactions of phenolic components with metals in weakly acidic and neutral media. The mode of coordination between fulvic acid and metals will vary with pH and with the metal: fulvic acid ratio.

SummaryMicrobial thermograms have been used to investigate the growth ofStreptococcus thermophilusandLactobacillus bulgaricusin single and mixed culture in milk medium. Growth has been observed with different ratios of the strains in the inoculum and, at one ratio, the effect of the amount of inoculum. The effect of serial sub-culture both with and without pH control has been observed, and stimulation ofStr. thermophilusby cell-free fitrates ofL. bulgaricushas been examined. The development of the technique is discussed in terms of the application of microbial thermograms in selecting cultures for incorporation into mixtures and evaluating their performance.

A fibre optic nephelometer was evaluated for use in measuring yeast cell numbers during the aerobic growth of yeast in grape juice. The response of the nephelometer to yeast cells in suspension decreased with increasing sugar concentration, and the decrease was dependent on the yeast population. Yeast cell number could be corrected from the observed nephelometer response with a calibration factor dependent on sugar concentration. Yeast populations as determined from the nephelometer response were compared to those determined by haemocytometer and optical density.

A method is presented for the pre-column derivatization of agmatine, arginine, citrulline and ornithine with o-phthalaldehyde-2-mercaptoethanol, and subsequent separation of the derivatives by reversed-phase liquid chromatography. Flourescent response is linear from 10 to 150 pmol of injected analyte and detection limits range from 28 to 100 fmol. Response factors relative to the internal standard, homocysteic acid, were 1.16 (agmatine and arginine), 1.03 (citrulline) and 0.34 (ornithine). The applicability of the method to the measurement of arginase, arginine deiminase, arginine decarboxylase and other enzyme in bacterial extracts was examined.