Testing of a (Spiritual) Self-Assessment Tool ((S)SAT) in a Community Hospital Setting

The (Spiritual) Self-Assessment Tool Study was designed to test the novel engagement tool's effectiveness. Providing the (Spiritual) Self-Assessment Tool Study to newly admitted medical patients led to few instances where the tool was completed. Nevertheless, the (Spiritual) Self-Assessment Tool Study patient questionnaire generated significant secondary findings: a third of responding patients consider their hospital care incomplete without their care team having access to (Spiritual) Self-Assessment Tool data. Nursing staff also desire this data, but are unable to access it without the (Spiritual) Self-Assessment Tool or an equivalent source.

Building Novel Research Capacity in a Regional Medical Campus Emergency Medicine Program: 1.0 Origins and Partnerships

The Emergency Medicine Researchers of Niagara (EMRoN) program is an evolving research incubator with the Niagara Regional Campus (NRC) of McMaster University’s Michael G DeGroote School of Medicine and Niagara Health (NH) that is becoming a productive research organization aligned with the strategic priorities of its partner organizations (NRC and NH). EMRoN is committed to advancing local community health care standards and sharing best practices with provincial and national peers.  In its first two years of operation EMRoN has achieved success in new structures, processes and outcomes that position it well to be a fulsome research organization for years to come.

Clinical leadership in reducing risk: Managing patient airways

Niagara Health, a multi-site hospital organization, has developed a multimodal, comprehensive strategy to manage patients with a Difficult Airway (DA) in a non-operative setting. The Difficult Airway Pathway (DAP) is an evidence-based strategy aimed to train staff to reduce critical events. The DAP initiative aligns with the LEADS framework for change management and includes an annual review of reported critical incidents and an Enterprise Risk Management (ERM) Assessment Summary, with the goal to "create a regional systematic approach to support personnel, equipment and education." The guiding vision is: "Right people, Right equipment, Right timing: No failed airway." Preliminary evaluation suggests the strategy reduces morbidity and mortality of difficulty airway incidents outside the operating room.

Precision large field scanning system for high numerical aperture lenses and application to femtosecond micromachining of ophthalmic materials

A precision, large stroke (nearly 1 cm) scanning system was designed, built, and calibrated for micromachining of ophthalmic materials including hydrogels and cornea (excised and in vivo). This system comprises a flexure stage with an attached objective on stacked vertical and horizontal translation stages. This paper outlines the design process leading to our most current version including the specifications that were used in the design and the drawbacks of other methods that were previously used. Initial measurements of the current version are also given. The current flexure was measured to have a 27 Hz natural frequency with no load.

Cooperative stimulation of vascular endothelial growth factor expression by hypoxia and reactive oxygen species: the effect of targeting vascular endothelial growth factor and oxidative stress in an orthotopic xenograft model of bladder carcinoma

Elevated thymidine phosphorylase has been shown to correlate with increased angiogenesis and poor prognosis in many cancers including transitional cell carcinoma of the bladder. In vitro studies have demonstrated that thymidine phosphorylase activity causes cellular oxidative stress and increases secretion of vascular endothelial growth factor. In this study, we show that thymidine phosphorylase activity also augments levels of the hypoxia-inducible factor-1α during in vitro hypoxia, and that thymidine phosphorylase activity and hypoxia act in concert to increase vascular endothelial growth factor (VEGF) secretion. We also demonstrate that thymidine phosphorylase overexpression confers tumorigenicity on an orthotopically implanted transitional cell carcinoma cell line. Administration of the antioxidant N-acetylcysteine together with a blocking anti-VEGF antibody abrogates the increase in tumorigenicity. Our results support the increased efficacy of combination approaches to antiangiogenic therapy.

Assessing the accuracy of a computerized decision support system for digoxin dosing in primary care: an observational study

BACKGROUND

This study was carried out as part of a European Union funded project (PharmDIS-e+), to develop and evaluate software aimed at assisting physicians with drug dosing. A drug that causes particular problems with drug dosing in primary care is digoxin because of its narrow therapeutic range and low therapeutic index.

OBJECTIVES

To determine (i) accuracy of the PharmDIS-e+ software for predicting serum digoxin levels in patients who are taking this drug regularly; (ii) whether there are statistically significant differences between predicted digoxin levels and those measured by a laboratory and (iii) whether there are differences between doses prescribed by general practitioners and those suggested by the program.

METHODS

We needed 45 patients to have 95% Power to reject the null hypothesis that the mean serum digoxin concentration was within 10% of the mean predicted digoxin concentration. Patients were recruited from two general practices and had been taking digoxin for at least 4 months. Exclusion criteria were dementia, low adherence to digoxin and use of other medications known to interact to a clinically important extent with digoxin.

RESULTS

Forty-five patients were recruited. There was a correlation of 0.65 between measured and predicted digoxin concentrations (P < 0.001). The mean difference was 0.12 microg/L (SD 0.26; 95% CI 0.04, 0.19, P = 0.005). Forty-seven per cent of the patients were prescribed the same dose as recommended by the software, 44% were prescribed a higher dose and 9% a lower dose than recommended.

CONCLUSION

PharmDIS-e+ software was able to predict serum digoxin levels with acceptable accuracy in most patients.

Differential and cell-specific expression of calcitonin receptor-like receptor and receptor activity modifying proteins in the human uterus

The calcitonin receptor-like receptor (CRLR) can function as a receptor for either calcitonin gene-related peptide (CGRP) or adrenomedullin (AM), depending upon co-expression with members of a novel family of receptor activity-modifying proteins (RAMP). RAMP1 presents the CRLR at the cell surface as a CGRP/AM receptor. RAMP2- and RAMP3-transported CRLR receptors act as AM-specific receptors. However, it is still unknown if this signalling system operates in vivo. Of particular interest is the uterus, where both peptides and their binding sites are known to be present and where both mitogenic and vasodilatory responses to AM and CGRP have been demonstrated. In this study, we examined whether CRLR and RAMP are co-expressed in the same populations of cells in human uterine tissue. Analysis by in-situ hybridization and immunocytochemistry revealed a heterogeneous and cell type-specific distribution of components of this AM/CGRP signalling system. Adrenomedullin mRNA was expressed and evenly distributed across all cell types. CRLR mRNA was predominantly found in blood vessels. RAMP1 expression was specific to myometrial myocytes and vascular smooth muscle cells in uterine arteries. RAMP2 and RAMP3 mRNA were not detectable by in-situ hybridization. The pattern of differential and cell-specific expression of CRLR and RAMP suggests the involvement of CRLR/RAMP1 in the processes of vasodilation, smooth muscle relaxation and angiogenesis in response to AM and CGRP in the human uterus, but also indicates that other receptors may be implicated.

A mechanism regulating proteolysis of specific proteins during renal tubular cell growth

Growth factors suppress the degradation of cellular proteins in lysosomes in renal epithelial cells. Whether this process also involves specific classes of proteins that influence growth processes is unknown. We investigated chaperone-mediated autophagy, a lysosomal import pathway that depends on the 73-kDa heat shock cognate protein and allows the degradation of proteins containing a specific lysosomal import consensus sequence (KFERQ motif). Epidermal growth factor (EGF) or ammonia, but not transforming growth factor beta1, suppresses total protein breakdown in cultured NRK-52E renal epithelial cells. EGF or ammonia prolonged the half-life of glyceraldehyde-3-phosphate dehydrogenase, a classic substrate for chaperone-mediated autophagy, by more than 90%, whereas transforming growth factor beta1 did not. EGF caused a similar increase in the half-life of the KFERQ-containing paired box-related transcription factor, Pax2. The increase in half-life was accompanied by an increased accumulation of proteins with a KFERQ motif including glyceraldehyde-3-phosphate dehydrogenase and Pax2. Ammonia also increased the level of the Pax2 protein. Lysosomal import of KFERQ proteins depends on the abundance of the 96-kDa lysosomal glycoprotein protein (lgp96), and we found that EGF caused a significant decrease in lgp96 in cellular homogenates and associated with lysosomes. We conclude that EGF in cultured renal cells regulates the breakdown of proteins targeted for destruction by chaperone-mediated autophagy. Because suppression of this pathway results in an increase in Pax2, these results suggest a novel mechanism for the regulation of cell growth.

Thymidine phosphorylase induces carcinoma cell oxidative stress and promotes secretion of angiogenic factors

Thymidine phosphorylase (TP) (E.C. 2.4.2.4), also known as platelet-derived endothelial cell growth factor, is a potent angiogenic factor. The expression of TP correlates with poor prognosis in a range of tumor types. 2-Deoxy-D-ribose-1-phosphate, a product of thymidine catabolism by TP, is a strongly reducing sugar that generates oxygen radical species during the early stages of protein glycation. We show that thymidine induces oxidative stress in TP-overexpressing carcinoma cells, promoting secretion of the stress-induced angiogenic factors vascular endothelial growth factor and interleukin-8, and inducing matrix metalloproteinase-1. Our findings outline a putative mechanism for TP-induced angiogenesis and identify novel targets for intervention.

Thyroid hormone resistance and increased metabolic rate in the RXR-gamma-deficient mouse

Vitamin A and retinoids affect pituitary-thyroid function through suppression of serum thyroid-stimulating hormone (TSH) levels and TSH-beta subunit gene expression. We have previously shown that retinoid X receptor-selective (RXR-selective) ligands can suppress serum TSH levels in vivo and TSH-beta promoter activity in vitro. The RXR-gamma isotype has limited tissue distribution that includes the thyrotrope cells of the anterior pituitary gland. In this study, we have performed a detailed analysis of the pituitary-thyroid function of mice lacking the gene for the RXR-gamma isotype. These mice had significantly higher serum T4 levels and TSH levels than did wild-type (WT) controls. Treatment of RXR-gamma-deficient and WT mice with T3 suppressed serum TSH and T4 levels in both groups, but RXR-gamma-deficient mice were relatively resistant to exogenous T3. RXR-gamma-deficient mice had significantly higher metabolic rates than did WT controls, suggesting that these animals have a pattern of central resistance to thyroid hormone. RXR-gamma, which is also expressed in skeletal muscle and the hypothalamus, may have a direct effect on muscle metabolism, regulation of food intake, or thyrotropin-releasing hormone levels in the hypothalamus. In conclusion, the RXR-gamma isotype appears to contribute to the regulation of serum TSH and T4 levels and to affect peripheral metabolism through regulation of the hypothalamic-pituitary-thyroid axis or through direct effects on skeletal muscle.

Reverse transcription polymerase chain reaction analysis of pituitary hormone, Pit-1 and steroidogenic factor-1 messenger RNA expression in pituitary tumors

Pit-1 is a transcription factor that appears early in embryonic pituitary gland formation and is necessary for the development of somatotropes, lactotropes and thyrotropes. Steroidogenic factor-1 (SF-1) is another early appearing transcription factor that is involved in the development of gonadotropes. In this study we have compared RT-PCR analysis of hormone mRNA with traditional IHC for classification of 27 pituitary tumors and have evaluated the correlation of Pit-1 and SF-1 mRNA with hormone mRNA. RT-PCR detected concordant hormone mRNA in 100% of GH IHC positive, 100% of PRL IHC positive, 33% of TSH IHC positive, and 93% of gonadotropin IHC positive tumors. IHC, however, was concordant in only 71% of GH mRNA positive, 78% of PRL mRNA positive, 17% of TSH beta mRNA positive, and 76% of FSH beta mRNA positive tumors. Pit-1 mRNA was positive in 87% of tumors in which mRNA for GH, PRL or TSH beta was detected and in only 17% of GH, PRL and TSH beta mRNA negative tumors. SF-1 mRNA was positive in 94% of tumors in which mRNA for FSH beta was present and in no FSH beta mRNA negative tumors. We conclude that RT-PCR analysis of hormone mRNA may be more sensitive than traditional hormone IHC for classification of pituitary tumors. Furthermore, tumor Pit-1 mRNA positively correlates with GH, PRL and TSH beta mRNA while tumor SF-1 mRNA correlates well with FSH beta mRNA. Combined analysis of hormone and transcription factor mRNA in pituitary tumor tissue may therefore be a more meaningful approach to pituitary tumor characterization.

Thymidine phosphorylase, 2-deoxy-D-ribose and angiogenesis

Angiogenesis is the term used to describe the formation of new blood vessels from the existing vasculature. In order to attract new vessels, a tissue must release an endothelial-cell chemoattractant. 2-Deoxy-D-ribose is produced in vivo by the catalytic action of thymidine phosphorylase (TP) on thymidine and has recently been identified as an endothelial-cell chemoattractant and angiogenesis-inducing factor. TP, previously known only for its role in nucleotide salvage, is now known to be angiogenic. TP expression is elevated in many solid tumours and in chronically inflamed tissues, both known areas of active angiogenesis. There is evidence that TP is also involved in physiological angiogenesis such as endometrial angiogenesis during the menstrual cycle. The majority of known endothelial-cell chemoattractants are polypeptides that bind to endothelial-cell-surface receptors. In contrast, 2-deoxy-D-ribose appears to lack a cell-surface receptor. Glucose is another sugar that acts as an endothelial-cell chemoattractant. The migratory activity of glucose is blocked by ouabain. It is possible that 2-deoxy-D-ribose and glucose stimulate endothelial-cell migration via a similar mechanistic pathway.

Serum ferritin. Screening test for colorectal cancer?

PURPOSE

There is increasing evidence that screening for colorectal cancer may save lives, and consequently, both professional and public interest in screening for colorectal cancer is increasing. As yet, however, there is no perfect screening test. Insidious blood loss is a common feature of colorectal cancer and may lead to a fall in serum ferritin before the patient becomes anemic. Measurement of serum ferritin, which is widely available and easily and inexpensively performed, has, therefore, been postulated as a potential screening test for colorectal cancer.

METHOD

This study used samples of serum collected from 148 patients recruited to a screening study for colorectal cancer. All patients were thoroughly investigated by double-contrast barium enema and/or colonoscopy. Patients were selected randomly from each of three clinical diagnostic groups: 50 patients with proven colorectal cancer, 49 patients without colon disease, and patients with adenomas of the colon. Serum ferritin was assayed by immunoradiometry. The expected adult reference ranged is 25 to 350 milligrams, and results were reported without patient identification.

RESULTS

There were no significant differences in serum ferritin levels among any of the three groups.

CONCLUSION

Serum ferritin is unlikely to be of value as a screening test for colorectal cancer.

The thyrotrope-restricted isoform of the retinoid-X receptor-gamma1 mediates 9-cis-retinoic acid suppression of thyrotropin-beta promoter activity

TSHbeta is a subunit of TSH that is uniquely expressed and regulated in the thyrotrope cells of the anterior pituitary gland. Thyroid hormone receptors (TR) are known to mediate T3 suppression of TSHbeta gene expression at the level of promoter activity. The role of other nuclear receptors in regulation of this gene is less clearly defined. Retinoid X receptors (RXR) are a family of nuclear transcription factors that function both as 9-cis-retinoic acid (RA) ligand-dependent receptors and heterodimeric partners with TR and other nuclear receptors. Recently, the RXR isoform, RXRgamma, has been identified in the anterior pituitary gland and found to be restricted to thyrotrope cells within the pitutiary. In this report, we have further characterized the distribution of RXRgamma1, the thyrotrope-restricted isoform of RXRgamma, in murine tissues and different cell types. We have found that RXRgamma1 mRNA and protein are expressed in the TtT-97 thyrotropic tumor, but not the thyrotrope-variant alphaTSH cells or somatotrope-derived GH3 cells. Furthermore, we have studied the effects of RXRgamma1 on TSHbeta promoter activity and hormone regulation in these pituitary-derived cell types. Both T3 and 9-cis-RA independently suppressed promoter activity in the TtT-97 thyrotropes. Interestingly, the combination of ligands suppressed promoter activity more than either alone, indicating that these hormones may act cooperatively to regulate TSHbeta gene expression in thyrotropes. The RXRgamma1 isoform was necessary for the 9-cis-RA-mediated suppression of TSHbeta promoter activity in alphaTSH and GH3 cells, both of which lack this isoform. RXRbeta, a more widely distributed isoform, did not mediate these effects. Finally, we showed that the murine TSHbeta promoter region between -200 and -149 mediated a majority of the 9-cis-RA suppression of promoter activity in thyrotropes. This region is distinct from the T3-mediated response region near the transcription start site. These data suggest that retinoids can mediate TSHbeta gene regulation in thyrotropes and the thyrotrope-restricted isoform, RXRgamma1, is required for this effect.

Interferon-gamma and urine neopterin in attacks of the hyperimmunoglobulinaemia D and periodic fever syndrome

The hyperimmunoglobulinaemia D and periodic fever (hyper-IgD) syndrome is typified by recurrent unpredictable febrile attacks with abdominal pain, joint involvement (arthralgias/arthritis), headache, skin lesions and a polyclonal elevation of serum IgD (> 100 U mL-1). Interferon-gamma (IFN-gamma) is a major proinflammatory cytokine which could play a role in the pathogenesis of the attacks. There is a need for parameters (if possible non-invasive) to monitor disease activity. A potential candidate is neopterin which is released by monocytes/macrophages when stimulated with IFN-gamma, excreted unchanged in urine, and appears to be an early and sensitive marker for activation of the immune system. We measured rectal body temperature, serum IFN-gamma, and urine neopterin in 10 hyper-IgD patients both during and between attacks. The body temperature rose to a mean of 38.9 degrees C on the first day of the attack and normalized within 5 days. Serum IFN-gamma during the first day of the attack was 2.98 IU mL-1 and was significantly lower during remissions. The urine neopterin excretion was 268 +/- 170 mumol mol-1 creatinine between attacks and was significantly increased to 638 +/- 275 mumol mol-1 creatinine on the first day of symptoms. Maximal urine neopterin values were reached on the fourth day of the attack (1051 +/- 387 mumol mol-1 creatinine) and excretion gradually declined and attained values below 400 mumol mol-1 creatinine after 9 days. There was a good correlation between serum IFN-gamma and urine neopterin.(ABSTRACT TRUNCATED AT 250 WORDS)

Normocalcemic effect of gallium nitrate in a hypercalcemic rat model

An established rat hypercalcemia model was used to study the effects of gallium nitrate on elevated serum calcium levels. Gallium nitrate was administered by i.v. or i.p. injection at daily doses of 0.07-0.45 mmol/kg for 5 days to the hypercalcemic rats beginning 1 day following surgery. A dose-correlated normocalcemic response was observed. Gallium nitrate administered late after the induction of the hypercalcemic state was also effective in reducing serum calcium levels. The p.o. administration, however, even at doses as high as 0.45 mmol/kg, did not reduce serum calcium to normal levels. The values of area under the concentration versus time curve (0-24 h) of gallium in normal rats were comparable after i.v. [49.2 (micrograms/ml)h] or i.p. [57.0 (micrograms/ml)h] injections. In contrast, the p.o. route achieved only 15% bioavailability, which may explain the ineffectiveness of p.o. administered gallium nitrate at that dose level. This study suggests that daily i.v. bolus injections of gallium nitrate for managing hypercalcemia may be potentially as effective as the current regimen of continuous i.v. infusion.

Determination of peplomycin in mouse tissues and biofluids by radioimmunoassay

Peplomycin, an antitumour antibiotic analogue of bleomycin, was measured in mouse tissues using a rapid radioimmunoassay. Antiserum, obtained by immunizing rabbits with peplomycin-bovine serum albumin conjugate, showed no significant cross-reactivity with the closely related peplomycin analogues bleomycin and liblomycin, nor with a number of other structurally unrelated antitumour drugs. The assay is sensitive and can detect peplomycin levels as low as 2 ng ml-1. The relative intra- and inter-assay standard deviation is < or = 5%, indicating good assay reproducibility. Peplomycin levels in mouse tissues were easily determined without extraction. Fifteen minutes after administration of a single intraperitoneal dose of peplomycin at 8.5 mg kg-1 (1/10 of LD50), high drug levels were found in plasma (46 micrograms ml-1), kidneys (38 micrograms g-1), urine and bladder (32 micrograms ml-1), followed by gastrointestinal tract (13 micrograms g-1), lung (8 micrograms g-1), spleen (3.7 micrograms g-1), heart (3.6 micrograms g-1), gall bladder (2.7 micrograms g-1), liver (2 micrograms g-1), and brain (0.6 microgram g-1). The total amount of drug in all these organs accounted for more than 80% of the dose administered. We conclude that the radioimmunoassay is sensitive and reproducible and is an ideal tool for measuring peplomycin in tissues and biofluids for pharmacological studies.

Effect of acute mild hypoglycaemia on counterregulatory responses to moderate hypoglycaemia induced immediately afterwards in healthy men

1. This study was designed to determine whether a 1 h period of mild hypoglycaemia (3.3 or 3.7 mmol/l) affected the response to an episode of moderate hypoglycaemia (2.5 mmol/l) immediately afterwards. 2. Eleven non-obese healthy men (age 26 +/- 1 years, mean +/- SEM) underwent three separate 3 h hyper-insulinaemic glucose clamps in single-blind, random order. On all three occasions, blood glucose was 4.5 mmol/l for the first hour, and on a control visit was maintained at this level for the second hour. In the other two visits, blood glucose was lowered to 3.7 or 3.3 mmol/l during the second hour. In the third hour, blood glucose was lowered to 2.5 mmol/l on all three visits. 3. In the second hour, adrenaline rose significantly (P < 0.05, analysis of variance) with a blood glucose of 3.3 and 3.7 mmol/l, as did cortisol and heart rate at 3.3 mmol/l, but glucagon, prolactin, sweating rate, symptom score and blood pressure were the same during the second hour on all three visits. 4. In the final hour at 2.5 mmol/l, there were no differences in adrenaline, noradrenaline, glucagon, prolactin, cortisol, symptom score, heart rate, blood pressure or sweating rate. 5. Thus, the overall magnitude of hormonal responses to moderate hypoglycaemia (2.5 mmol/l) are not modified by exposure to mild hypoglycaemia (3.3 or 3.7 mmol/l) for 1 h immediately beforehand.

Urine neopterin as a parameter of disease activity in patients with systemic lupus erythematosus: comparisons with serum sIL-2R and antibodies to dsDNA, erythrocyte sedimentation rate, and plasma C3, C4, and C3 degradation products

OBJECTIVES--To investigate urine neopterin as a parameter of disease activity in an unselected group of patients with systemic lupus erythematosus (SLE) and to study the relation between urine neopterin and certain patterns of organ disease and differing drug regimens in the treatment of SLE. METHODS--Neopterin was determined by high performance liquid chromatography in 115 early morning urine samples from 68 patients with SLE. Serum soluble interleukin 2 receptor (sIL-2R) and antibodies to double stranded DNA (dsDNA) were determined by enzyme linked immunosorbent assay (ELISA), and the erythrocyte sedimentation rate (ESR), plasma C3, C4, and C3 degradation products (C3dg) were measured in corresponding blood samples. Disease activity was scored using the British Isles Lupus Assessment Group (BILAG) index. RESULTS--Urine neopterin was significantly increased in patients with active and inactive SLE compared with the control group and was significantly higher in patients with active than in those with inactive SLE. Urine neopterin did not distinguish between subsets of patients with SLE with particular patterns of organ disease, as defined by the BILAG index, nor was its level primarily influenced by differing drug regimens. Levels of serum sIL-2R, antibodies to dsDNA, the ESR, and plasma C3, C4, and C3dg were also significantly different between the patients with active and inactive SLE. Unlike urine neopterin there was considerable overlap in the values of these parameters between the two activity groups. Highly significant correlations found between urine neopterin and serum sIL-2R, ESR, and plasma C3, C4, and C3dg suggest the close association of neopterin with clinical activity in SLE. Multivariate logistic regression analysis showed that urine neopterin > 300 mumol/mol creatinine was a highly significant predictor of disease activity with an odds ratio of 3.51. CONCLUSIONS--Determination of urine neopterin, a non-invasive, relatively simple and inexpensive measurement, appears to be the best parameter for assessing and monitoring disease activity and treatment in patients with SLE.

Clinical pharmacology of 11-acetyl-8-carbamoyloxymethyl-4-formyl-14-oxa-1,11-diazatetracyclo (7.4.1.0(2,7).0(10,12) tetradeca-2,4,6-trien-6,9-diyl diacetate (FK 973)

FK 973, a novel substituted dihydrobenzoxazine structurally similar to mitomycin C, is a derivative of the product isolated from Streptomyces sandaensis. In vitro and in rodents, it is a potent antitumor agent. During Phase I clinical trials, we evaluated the pharmacologic properties of FK 973 in eight adenocarcinoma patients after a 30-min i.v. infusion of doses ranging from 7 to 45mg/m2. An established enzyme immunoassay that measures the stable deacetylated active metabolite FR66980 showed that the plasma drug levels declined biphasically with a terminal half life (t1/2 beta) of 4.7 +/- 1.6hr (mean +/- S.D.) The total clearance rate was 438 +/- 113ml/(min/m2). Both the maximum plasma drug concentrations (Cmax) and the area under the concentration-versus-time curve (AUC) were dose related. In addition to nausea and vomiting, alopecia, and myelosuppression, three patients experienced a delayed vascular-leak syndrome. The 3 patients had received doses among the highest studied, and the toxicity appeared to be dose related and cumulative. The evidence suggests that higher doses generated higher Cmax and AUC values, which may be correlated with toxic effects.

Depletion of patients' plasma tryptophan using tryptophan side-chain oxidase columns

The use of the enzyme tryptophan side-chain oxidase, isolated from Pseudomonas XA, was explored in 3 patients with refractory acute lymphocytic leukemia. Patients were given either a low-tryptophan diet or tryptophan-free hyperalimentation, prior to and during therapy. Their plasma, separated by pheresis, was continuously passed through a tryptophan depletion column containing the immobilized tryptophan side-chain oxidase. Up to 4 plasma volumes were passed through the column daily, 5 days per week for 2-3 weeks, and plasma tryptophan levels, both free and total, were measured by high-performance liquid chromatography. Pre- and postcolumn plasma samples were collected throughout the pheresis procedure. All postcolumn plasma samples had unmeasurable tryptophan levels throughout the treatment period, whereas precolumn samples were always measurable. Generally, tryptophan levels of plasma isolated from peripheral blood decreased after therapy, but rebounded by the next day. The enzyme depletion column reduces circulating plasma tryptophan levels, and its use is well tolerated by patients. However, further development of this method will require study of the effects of diet and of the duration, interval, and frequency of use of this column on therapeutic efficacy. Problems include difficulties with extended diet compliance and apparently intensive mobilization of tryptophan from body stores, which may preclude the clinical application of this enzyme depletion column.

Clinical pharmacology of combined oral uracil and ftorafur

Phase I clinical trials of the combination of oral uracil with ftorafur (Ft) were conducted in patients with solid tumors over either a 5-day (345 mg/m2/day) or a 28-day (160 mg/m2/day) period. The uracil dose, which was four times the Ft dose (molar basis), was previously shown to be optimal at inhibiting the degradation of 5-fluorouracil (5-FU). Pharmacology was performed on the first dose of the first day of therapy. Ft was measured by HPLC, whereas uracil and 5-FU were measured using GC/MS. Plasma levels were highest for Ft, followed by uracil and 5-FU at all time points. Peak and trough levels after selected subsequent doses were also measured; these varied in the individual from day to day. Maximum plasma levels (Cpmax) for Ft, uracil, and 5-FU except in one patient were achieved at 0.6-2.1 hr, 0.6-4.1 hr, and 0.7-2.0 hr, respectively. Generally, lower doses yielded more rapid decay of 5-FU and uracil levels than did higher doses. No correlation was observed between myelotoxicities (granulocytopenia and leukopenia) and the Cpmax and AUC0-6hr of Ft (p > 0.2). However, after the highest uracil and Ft dose (approximately 300 mg/m2/Ft study dose), the Cpmax and AUC0-6hr values of 5-FU revealed significant differences (p < 0.05) in three patients each with and without myelotoxicity. These associations were similarly observed with uracil. Our findings thus indicate that measuring plasma uracil and more importantly, the 5-FU levels, may predict hematological toxicity and enable subsequent dose adjustments.

Safe, stable, whole blood samples for quality assessment of glucose measurement by non-laboratory staff

A whole blood control material has been used to assess the analytical performance of non-laboratory staff who use glucose meters in clinical areas. It is prepared from sterile horse blood which is readily available from a commercial source. There are no known infection or disease transmission risks to users. When the material is stabilized by the addition of sodium fluoride less than 3% loss of glucose over 48 h is observed from an initial value of 10 mmol/L. However, we prefer to stipulate that the glucose is measured on the day of receipt. The material has been used successfully with Reflolux IIM meters and B-M sticks (Boehringer Mannheim, UK) for over a year in our hospital.

Klüver-Bucy syndrome and psychiatric illness

A 52-year-old woman, whose initial psychiatric presentation at the age of 15 was with a disorder resembling schizophrenia, developed symptoms of Klüver-Bucy syndrome, and is now thought to suffer from an organic psychotic disorder. Klüver-Bucy syndrome must be distinguished from symptoms of schizophrenia or affective disorder; its presence suggests an organic process.

A comparison of the effects of tetraplatin and cisplatin on renal function and gentamicin pharmacology in rats

Tetraplatin (tetrachloro[d,l-trans]1,2-diaminocyclohexane platinum IV (TTP)) is a new platinum analogue active against L1210 murine leukemia that is resistant to cisplatin (diamminedichloroplatinum II (DDP)). Since nephrotoxicity is a significant problem with DDP therapy, we compared the effects of equitherapeutic doses of TTP and DDP on renal structure and function in rats. We also studied the effects of the 2 platinum compounds on the distribution and excretion of gentamicin (GENT), an antibiotic that is excreted solely by the kidneys. Rats treated intravenously with 2.85 mg/kg of DDP on days 1, 5 and 9 had significantly different plasma urea nitrogen (BUN) levels and creatinine clearance rates on day 16 than those given the same doses of TTP. The renal function of TTP-treated rats did not differ from that of controls or rats given only GENT. Twenty-four hours after a single GENT dose (given on day 15), DDP-treated rats had higher GENT concentrations in the plasma, liver and spleen than rats given GENT alone. TTP-treated rats had higher GENT levels only in the spleen. DDP-treated rats retained a higher percentage of the injected platinum in the renal cortex than those treated with TTP. Light microscopic examination of renal tissue showed necrotic cells and dilated tubules in the proximal tubules of DDP-treated rats while the kidneys of TTP-treated rats were largely indistinguishable from those of controls. Thus, our results indicate that the distribution of platinum in the kidneys differs between rats treated with TTP and those treated with DDP. This may partly explain the considerably lower nephrotoxicity of TTP.

Metabolism and disposition of (R)-4-[3-(2-hydroxy-2-phenyl)ethylamino-3-methylbutyl]benzamide Hcl (LY 195448) in rodents

The disposition and metabolism of (R)-4-[3-(2-hydroxy-2-phenyl)ethylamino-3-methylbutyl]benzamide HCl, or LY 195448 (LY), were studied in rodents 1 hr following a single iv injection of 14C-LY at 30 mg/m2 (10 mg/kg mice and 5 mg/kg rats), In all tissues and carcases, recovery of 14C was nearly complete. The majority of radioactivity was recovered from intestine (40%) whereas liver and urine accounted for 10% each, kidney for 3-5%, and plasma for 1-3% of total administered radioactivity. Analyzing by HPLC and TLC, para-hydroxy-LY (para-OH-LY) in addition to unchanged drug, was found in all tissues. Meta-OH-LY was detected only in urine, intestine and kidney. These metabolites were found to be conjugated with either glucuronide or sulfate moieties. Peaks coeluting with authentic para-OH-meta-methoxy-LY and di-OH-LY were also observed.

Clinical pharmacology of polyethylene glycol-L-asparaginase

Polyethylene glycol (PEG)-L-asparaginase, at doses ranging from 500 to 8000 units/m2, was infused iv over 60 min in 31 patients of whom 27 were evaluable pharmacokinetically. The plasma disappearance of PEG-L-asparaginase is described by a monophasic curve with a mean half-life of 357 +/- 243 hr which is much longer than that of the unconjugated enzyme (half-life of approximately 20 hr). The rate of total clearance (128 +/- 74 ml/m2 X day) is much slower than that of L-asparaginase (2196 +/- 1098 ml/m2 X day). The volume of distribution is 2093 +/- 643 ml/m2, which is similar to that of L-asparaginase, indicating that PEG-L-asparaginase is mainly localized in the plasma. No enzyme could be measured in urine samples taken from nine patients for a period of up to 4 days. Additionally, no enzyme was measurable in one patient's pleural fluid obtained at the end of infusion and 6 days after infusion of a 1000-unit/m2 dose; the corresponding concentrations in plasma were 0.64 and 0.62 units/ml, respectively. In general, the plasma enzyme concentrations at the end of the 1-hr infusion and at 14 days after drug administration were proportional to the dose given. However, in two patients, a sudden disappearance of enzyme levels occurred which preceded anaphylactic reactions during subsequent treatment. A third patient developed severe bronchospasm 30 min after the first dose, but his enzyme levels were within the normal range.

Peplomycin and bleomycin effects on human colon cancer cells

The lethal effects of peplomycin and bleomycin on cultured human colon cancer cells (LoVo) were compared by using the technique of inhibition of colony formation. The survival of LoVo cells after treatment for 1 h with either peplomycin or bleomycin was characterized by a biphasic exponential curve. When the exposure time was extended to 24 h, both drugs produced much greater cytotoxic effects, with survival decreased to less than 0.10% for bleomycin and less than 0.02% for peplomycin. Both peplomycin and bleomycin, in a dose-dependent manner, inhibited the incorporation of thymidine into cells. On an equal-weight basis, the cytotoxicity of peplomycin (24-h exposure) was similar to that of bleomycin. Both agent also inhibited the incorporation of leucine and uridine after 24 h of drug exposure, but to a lesser extent than inhibition of thymidine incorporation. However, after 1 h of exposure, such inhibitory effects were minimal. These results demonstrate that prolonged peplomycin or bleomycin exposure produces greater cell-kill than shorter drug exposure. Schedules with continuous drug administration should be explored clinically.

Radioimmunoassay for etoposide and teniposide

A radioimmunoassay for VP-16 or VM-26 was developed by using tritiated ligand and antisera produced from rabbits immunized with succinyl-VP-16 bovine serum albumin conjugates. Separate determinations of VP-16 and its hydroxy acid, a metabolite which cross-reacted with the VP-16 antisera, could be accomplished by extracting samples with chloroform in which the metabolite was insoluble. The assay was reproducible and sensitive. Extracted standard curves were linear from 0.025 to 5 micrograms for VP-16 and 0.1 to 10 micrograms for the hydroxy acid per 0.5 ml assay mixture. Fifty percent inhibition of binding was achieved at 0.066 and 0.55 microgram for VP-16 or VM-26 and the metabolite, respectively. Preliminary disposition studies in mice and dog, and human urinary excretion support the application of the assay in pharmacologic studies.

Clonidine is a better test for growth hormone deficiency than insulin hypoglycaemia

The oral clonidine test was compared with the standard intravenous insulin hypoglycaemia test in 41 children and adolescents with short stature. In those without growth hormone deficiency clonidine provoked a significantly higher mean plasma growth hormone response and gave fewer false subnormal responses (apparent growth hormone deficiency) than insulin. Children with psychosocial deprivation had poorer responses to both tests. In view of these findings and the absence of unacceptable side effects with clonidine it is concluded that the oral administration of this alpha-adrenergic stimulant is a safe and reliable alternative test of growth hormone release.

Clinical pharmacology of bruceantin by radioimmunoassay

During the phase I clinical trial of a new antitumor agent, bruceantin, the pharmacology was studied in 18 cancer patients. The drug was infused intravenously (IV) for 3 h at doses ranging from 1 to 3.6 mg/m2 per day for 5 days. The plasma drug disappearance curves were biphasic, with a fast initial half-life of less than 15 min. The second half-life (t1/2 beta) varied from 0.7 to 38 h among different patients and was not dose-related. The difference between the t1/2 beta on day 1 and that on day 5 was not significant. In patients with normal liver function, the mean plasma concentration at the end of infusion was 22 ng/ml, and the value of the area under the concentration X time curve (AUC) was 111 (ng/ml)h. In contrast, in patients with abnormal liver function the corresponding values were 115 ng/ml and 830 (ng/ml)h, respectively. In addition, these patients had a slower elimination half-life of 10.9 h and a decreased total clearance of 157 ml/min/m2, as compared with 2.6 h and 671 ml/min/m2, respectively, for the normal group. All these differences were statistically significant. Patients with abnormal liver function developed more severe toxicity, including fever, severe nausea, vomiting, and hypotension. Two patients with severe hepatic dysfunction received a reduced dose and developed no toxicity. These results demonstrated the importance of the effects of liver dysfunction on drug disposition and showed that the dosage should be reduced in patients with hepatic dysfunction.

Does calcitonin cause hypocalcaemia after thyroidectomy?

Plasma calcitonin, parathyroid hormone, total thyroid hormones and calcium were measured in 6 patients before, during and after thyroidectomy for hyperthyroidism. In 4 patients, plasma calcium fell postoperatively by 0.23--0.46 mmol/l, but there was no change in calcitonin or parathyroid hormone levels. In one patient, in whom there was a postoperative fall in plasma calcium of 0.55 mmol/l, thyroid hormones rose to a peak at 1 h and calcitonin to a peak at 12 h after resection. However, the rise in calcitonin occurred 8 h after the initial decrease in plasma calcium. In this patient, parathyroid hormone levels showed a slight rise only. It is concluded that, while thyroid hormones and calcitonin may leak from the damaged thyroid remnant after surgery, it is unlikely that calcitonin is important in the production of postoperative hypocalcaemia. However, impaired parathyroid hormone secretion may be a contributing factor.

What is the significance of raised plasma TSH levels after thyroid surgery?

Thyroid function was assessed prospectively for five years in 73 patients treated surgically for Graves's disease. No patient developed hypothyroidism after the sixth postoperative month, despite the presence of raised plasma TSH levels in 70 per cent of euthyroid patients at the end of the first year. Indeed, in those with evidence of temporary hypothyroidism (low T4, raised TSh at 3 months but normalisation of T4 at 6 months) plasma TSH continued to fall for up to three years. The majority (6) of patients developing recurrent hyperthyroidism did so within the first year, but in one of three patients who relapsed subsequently, plasma TSH had been elevated at one year. Plasma TSH cannot be used to predict thyroid status following surgery for Graves' disease. Although regular review remains necessary, it should not include measurement of TSH unless this is needed to confirm the validity of a low thyroxine level after the third postoperative month and before starting permanent replacement therapy.

Prolactin response to metoclopramide in hyperthyroidism

The response of PRL to the oral administration of the dopamine receptor-blocking agent metoclopramide and the effect of metoclopramide on the TRH-induced release of PRL and TSH were measured in eight patients with hyperthyroidism and in eight age- and sex-matched euthyroid controls. As expected from the known direct inhibitory influence of thyroid hormones on pituitary TSH secretion, there was no TSH rise in response to metoclopramide in either group. PRL levels, on the other hand, rose significantly after the administration of metoclopramide in both the hyperthyroid and euthyroid subjects (P less than 0.0005 at 60 and 120 min). However, the increase in PRL at 120 min was significantly less in the hyperthyroid subjects than in the euthyroid controls (P less than 0.0025). Furthermore, the administration of metoclopramide failed to reestablish normal responsiveness of either PRL or TSH to TRH in the hyperthyroid subjects. We have previously suggested that thyroid hormones inhibit PRL secretion by stimulating the hypothalamic secretion of dopamine. These results suggest, however, that elevated levels of thyroid hormones also inhibit PRL release directly at the anterior pituitary level.

Effect of ECT on the neuroendocrine response to apomorphine in severely depressed patients

Animal studies have suggested that the mechanism of the antidepressant action of ECT may be to increase monoaminergic post-synaptic receptor sensitivity. We have tested this hypothesis in 12 drug-free patients suffering from severe depression, 11 of whom had depressive delusions. The responses of growth hormone, prolactin and cortisol to 0.75 mg subcutaneous apomorphine were examined before and after a successful course of ECT. There were no significant differences between hormonal measurements on the two occasions, with the exception that basal plasma cortisol concentrations were significantly lower following ECT and recovery from depressive illness. These results do not support the hypothesis that ECT increases dopaminergic post-synaptic receptor sensitivity.

Postoperative glucose tolerance during extradural analgesia

Thirteen patients undergoing lower abdominal gynaecological surgery were allocated to general anaesthesia (halothane and nitrous oxide) or general anaesthesia plus extradural analgesia (T8-S5). I.v. glucose tolerance tests were performed on the day before surgery and 8 h after skin incision. All patients having extradural analgesia (T8) were pain-free following surgery. Extradural analgesia blocked the hyperglycaemic response to surgery but not the late postoperative cortisol response, although values were significantly less than in the group receiving general anaesthesia alone. Impairment of glucose tolerance and of insulin response to the glucose load in the period after operation were not influenced by extradural analgesia and this may have resulted from insufficient inhibition of the stress-induced release of catecholamines or cortisol, or both, or from blockade of stimulatory efferent sympathetic pathways to pancreatic islets.

The effect of bromocriptine on insulin secretion and glucose tolerance in patients with acromegaly

The oral administration of bromocriptine 5 mg 6-hourly to twelve patients with acromegaly for a mean period of 12 (range 3-27) months significantly reduced whole blood glucose, plasma insulin and plasma growth hormone (GH) concentrations during a 50 g oral glucose tolerance test (OGTT). After this period of treatment, bromocriptine was withdrawn for 48 h resulting in a significant rise in whole blood glucose, plasma insulin and plasma GH concentrations during a repeat OGTT. It is concluded that bromocriptine therapy improves glucose tolerance in acromegaly by suppressing GH secretion and consequently GH-mediated antagonism of insulin.

Searching for the infertile man with hyperprolactinemia

The purpose of this study was to determine whether routine prolactin measurement was of use when investigating men with infertility. Prolactin levels were slightly higher in men with primary infertility, compared with men with secondary infertility and a fertile control group. Although this slight increase was statistically significant, most readings were within the laboratory normal range in all groups, and we did not find any clinically significant cases of hyperprolactinemia. We conclude that routine prolactin estimation is not justified unless there are other indications, e.g., impotence, dialysis, or a history of previous pituitary disease.

A radioimmunoassay for 5-methyltetrahydrohomofolate

A radioimmunoassay for 5-methyltetrahydrohomofolate has been developed by using antibody induced in rabbits by 5-methyltetrahydrohomofolate-bovine serum albumin conjugates. The labeled drug was prepared by condensing it with [3H]histamine or [125I]histamine. The assay employing either isotope was simple and reproducible and had identical sensitivities. The specificity of the antibody was characterized by comparing the effectiveness of various related compounds in displacing labeled 5-methyltetrahydrohomofolate from the binding site of the antisera. At concentrations up to 1000 microgram/ml, homofolate acid, tetrahydrohomofolic acid, folic acid and methotrexate showed no competition for the binding. 5-methyltetrahydrofolic acid and 5-formyltetrahydrofolic acid cross-reacted with the antisera; the concentrations producing 50% binding inhibition were 2.8 and 24 microgram, respectively, as compared to 0.01 microgram for 5-methyltetrahydrohomofolate. The assay can be used for measuring the drug in plasma and tissues. This study supports its usability for clinical pharmacologic studies.

Pharmacokinetics of cefoperazone in patients with neoplastic disease

The pharmacokinetics of cefoperazone, a new semisynthetic cephalosporin, were studied in 34 patients with neoplastic disease. This compound was administered in a variety of doses and schedules without observable toxicity in any patient. The mean peak serum concentration after a 15-min intravenous infusion of 2 g was 264 microgram/ml after the first dose; the serum half-life was 2.1 h. There was no significant change in half-life or serum concentrations after 4 or 7 days of therapy. The mean peak serum concentration after infusion of 1 g over 15 min was 133 microgram/ml, with a mean of 10.7 microgram/ml at 6 h. The serum half-life was 2 h. The mean peak serum concentration after infusion of 1 g over 0.5 h was 101 microgram/ml. When 8 g was subsequently administered daily by a continuous infusion schedule, levels were maintained at 80 microgram/ml. When the dose was increased to 16 g daily, serum concentrations were maintained at an average of 153 microgram/ml. Only 37% of cefoperazone was recovered in the urine in a 12-h period after the initial dose, suggesting the importance of other mechanisms of excretion; however, serum concentrations in one patient with renal insufficiency were significantly higher than serum concentrations in patients with normal renal function.

Sensitive radioimmunoassay for vancomycin

A radioimmunoassay for vancomycin has been developed which uses rabbit antiserum induced by vancomycin-bovine serum albumin conjugates and vancomycin labeled with 3H or 125I. Using either isotope, the method is simple and reproducible and has a sensitivity of 4 or 0.04 ng/ml, depending on the tracer used. This is 200- to 20,000-fold improvement in sensitivity compared with the most sensitive bioassay. Drug levels in serum or urine samples from patients receiving vancomycin can be determined by this assay procedure without processing. The data obtained with 3H and 125I labels were in good agreement. Patients' plasma vancomycin concentrations determined by radioimmunoassay correlated well with those determined by bioassay when the drug was administered intravenously. However, after oral administration the drug could be detected only by radioimmunoassay. The antiserum was evaluated for cross-reactivity with a wide variety of antibiotics and cancer chemotherapeutic agents, and no significant interference was found.

Influence of thyroid status on dopaminergic inhibition of thyrotropin and prolactin secretion: evidence for an additional feedback mechanism in the control of thyroid hormone secretion

Serum TSH and PRL concentrations were measured after the randomized oral administration of either metoclopramide, L-dopa, or placebo on 3 consecutive days to five patients with overt primary hypothyroidism (low serum total T4 and raised serum TSH) and to five patients with subclinical hypothyroidism (normal serum total T4 and raised serum TSH). In both groups there was a rise in serum TSH and PRL concentrations after metoclopramide and a fall after L-dopa when compared with the effect of the placebo. However, the rise in serum TSH and PRL concentrations was significantly greater in patients with subclinical hypothyroidism compared to that in patients with overt hypothyroidism. It was not possible to show any significant difference in the degree of fall of these pituitary hormones after L-dopa administration in the two groups. These results suggest that in addition to the established negative feedback of thyroid hormones at the level of anterior pituitary thyrotropes, there is a previously unrecognized effect of thyroid hormones at the hypothalamus, resulting in increased dopaminergic inhibition of TSH release. Stimulation of hypothalamic dopamine by thyroid hormones also inhibits PRL secretion.

Prevalence of subclinical thyroid failure in insulin-dependent diabetes

A study was made of the distribution of primary thyroid failure, indicated by a raised serum TSH concentration, in 605 (294 males and 311 females) insulin-dependent (type I) diabetics, aged 21-84 yr, not previously suspected of having thyroid disease. The prevalence of a raised serum TSH concentration in females of all ages (17%) was significantly greater (P less than 0.0005) than that in males (6.1%) and increased with increasing age at onset of diabetes (P less than 0.05) and age at time of study (P less than 0.001) in females but not in males. There was no significant difference in the duration of diabetes when comparing patients with normal and raised serum TSH concentrations. The prevalence of a raised TSH concentration in late-onset insulin-dependent diabetics was no greater in patients requiring insulin within 3 months of diagnosis of diabetes than in those exhibiting secondary sulfonylurea failure, who required insulin more than 3 months after diagnosis. In type I diabetes, the prevalence of subclinical primary thyroid failure is considerably greater than has previously been suspected, with female late-onset insulin-dependent diabetics being at the greatest risk.