Fracture risk after three bariatric surgery procedures in Swedish obese subjects: up to 26 years follow-up of a controlled intervention study

BACKGROUND

Previous studies have reported an increased fracture risk after bariatric surgery.

OBJECTIVE

To investigate the association between different bariatric surgery procedures and fracture risk.

METHODS

Incidence rates and hazard ratios for fracture events were analysed in the Swedish Obese Subjects study; an ongoing, nonrandomized, prospective, controlled intervention study. Hazard ratios were adjusted for risk factors for osteoporosis and year of inclusion. Information on fracture events were captured from the Swedish National Patient Register. The current analysis includes 2007 patients treated with bariatric surgery (13.3% gastric bypass, 18.7% gastric banding, and 68.0% vertical banded gastroplasty) and 2040 control patients with obesity matched on group level based on 18 variables. Median follow-up was between 15.1 and 17.9 years for the different treatment groups.

RESULTS

During follow-up, the highest incidence rate for first-time fracture was observed in the gastric bypass group (22.9 per 1000 person-years). The corresponding incidence rates were 10.4, 10.7 and 9.3 per 1000 person-years for the vertical banded gastroplasty, gastric banding and control groups, respectively. The risk of fracture was increased in the gastric bypass group compared with the control group (adjusted hazard ratio [adjHR] 2.58; 95% confidence interval [CI] 2.02-3.31; P < 0.001), the gastric banding group (adjHR 1.99; 95%CI 1.41-2.82; P < 0.001), and the vertical banded gastroplasty group (adjHR 2.15; 95% CI 1.66-2.79; P < 0.001).

CONCLUSIONS

The risk of fracture is increased after gastric bypass surgery. Our findings highlight the need for long-term follow-up of bone health for patients undergoing this treatment.

Oxidant status, iron homeostasis, and carotenoid levels of COPD patients with advanced disease and LTOT

Background: The pathogenesis of chronic obstructive pulmonary disease (COPD) is associated with oxidative stress. Both iron (Fe) and oxygen are involved in the chemical reactions that lead to increased formation of reactive oxygen species. Oxidative reactions are prevented by antioxidants such as carotenoids.

Objective: To study the differences in Fe status, carotenoid levels, healthy eating habits, and markers of inflammation and oxidative damage on proteins in subjects with severe COPD ± long-term oxygen therapy (LTOT) and lung-healthy control subjects.

Methods: Sixty-six Caucasians with advanced COPD (28 with LTOT) and 47 control subjects were included. Questionnaires about general health, lifestyle, and dietary habits were answered. Lung function tests and blood sampling were performed.

Results: COPD subjects (±LTOT) did not demonstrate increased oxidative damage, assessed by protein carbonylation (PC), while levels of soluble transferrin receptors (sTfRs) were slightly elevated. Soluble TfRs, which is inversely related to Fe status, was negatively associated with PC. Levels of carotenoids, total and β-cryptoxanthin, α- and β-carotenes, were significantly lower in COPD subjects, and their diet contained significantly less fruits and vegetables. Lutein correlated inversely with IL-6, lycopene correlated inversely with SAT, while β-carotene was positively associated with a Mediterranean-like diet.

Conclusions: Fe could favor oxidative stress in COPD patients, suggesting a cautious use of Fe prescription to these patients. COPD subjects ate a less healthy diet than control subjects did and would, therefore, benefit by dietary counseling. COPD patients with hypoxemia are probably in particular need of a lycopene-enriched diet.

A cross-scale trophic cascade from large predatory fish to algae in coastal ecosystems

Trophic cascades occur in many ecosystems, but the factors regulating them are still elusive. We suggest that an overlooked factor is that trophic interactions (TIs) are often scale-dependent and possibly interact across spatial scales. To explore the role of spatial scale for trophic cascades, and particularly the occurrence of cross-scale interactions (CSIs), we collected and analysed food-web data from 139 stations across 32 bays in the Baltic Sea. We found evidence of a four-level trophic cascade linking TIs across two spatial scales: at bay scale, piscivores (perch and pike) controlled mesopredators (three-spined stickleback), which in turn negatively affected epifaunal grazers. At station scale (within bays), grazers on average suppressed epiphytic algae, and indirectly benefitted habitat-forming vegetation. Moreover, the direction and strength of the grazer-algae relationship at station scale depended on the piscivore biomass at bay scale, indicating a cross-scale interaction effect, potentially caused by a shift in grazer assemblage composition. In summary, the trophic cascade from piscivores to algae appears to involve TIs that occur at, but also interact across, different spatial scales. Considering scale-dependence in general, and CSIs in particular, could therefore enhance our understanding of trophic cascades.

The incidence of albuminuria after bariatric surgery and usual care in Swedish Obese Subjects (SOS): a prospective controlled intervention trial

BACKGROUND

Obesity is associated with increased risk of chronic kidney disease and albuminuria is a predictor of renal impairment. Bariatric surgery reduces body weight in obese subjects, but it is not known whether surgery can prevent development of albuminuria. This study aims to determine the long-term effect of bariatric surgery on the incidence of albuminuria.

SUBJECTS

The Swedish Obese Subjects study is a non-randomized, prospective, controlled study conducted at 25 public surgical departments and 480 primary health care centers in Sweden. Between 1 September 1987 and 31 January 2001, 2010 participants who underwent bariatric surgery and 2037 controls were recruited. Inclusion criteria were age 37-60 years and BMI ⩾ 34 in men and BMI ⩾ 38 in women. In this analysis, we included 1498 patients in the surgery group and 1610 controls without albuminuria at baseline. Patients in the bariatric surgery group underwent banding (18%), vertical banded gastroplasty (69%) or gastric bypass (13%); controls received usual obesity care. Date of analysis was 1 January 2011. Median follow-up was 10 years, and the rates of follow-up were 87%, 74 and 52% at 2, 10 and 15 years, respectively. The main outcome of this report is incidence of albuminuria (defined as urinary albumin excretion >30 mg per 24 h) over up to 15 years.

RESULTS

During the follow-up, albuminuria developed in 246 participants in the control group and in 126 in the bariatric surgery group, corresponding to incidence rates of 20.4 and 9.4 per 1000 person years, respectively (adjusted hazard ratio, 0.37; 95% confidence interval, 0.30-0.47; P < 0.001). The expected number of surgeries needed to prevent the development of albuminuria in one patient at 10 years was nine.

CONCLUSIONS

Bariatric surgery is associated with reduced incidence of albuminuria compared with usual obesity care.

Macrophage gene expression in adipose tissue is associated with insulin sensitivity and serum lipid levels independent of obesity

OBJECTIVE

Obesity is linked to both increased metabolic disturbances and increased adipose tissue macrophage infiltration. However, whether macrophage infiltration directly influences human metabolism is unclear. The aim of this study was to investigate if there are obesity-independent links between adipose tissue macrophages and metabolic disturbances.

DESIGN AND METHODS

Expression of macrophage markers in adipose tissue was analyzed by DNA microarrays in the SOS Sib Pair study and in patients with type 2 diabetes and a BMI-matched healthy control group.

RESULTS

The expression of macrophage markers in adipose tissue was increased in obesity and associated with several metabolic and anthropometric measurements. After adjustment for BMI, the expression remained associated with insulin sensitivity, serum levels of insulin, C-peptide, high density lipoprotein cholesterol (HDL-cholesterol) and triglycerides. In addition, the expression of most macrophage markers was significantly increased in patients with type 2 diabetes compared to the control group.

CONCLUSION

Our study shows that infiltration of macrophages in human adipose tissue, estimated by the expression of macrophage markers, is increased in subjects with obesity and diabetes and associated with insulin sensitivity and serum lipid levels independent of BMI. This indicates that adipose tissue macrophages may contribute to the development of insulin resistance and dyslipidemia.

Effects of 11β-hydroxysteroid dehydrogenase-1 inhibition on hepatic glycogenolysis and gluconeogenesis

The aim of this study was to determine the effect of prolonged 11β-hydroxysteroid dehydrogenase-1 (11β-HSD1) inhibition on basal and hormone-stimulated glucose metabolism in fasted conscious dogs. For 7 days prior to study, either an 11β-HSD1 inhibitor (HSD1-I; n = 6) or placebo (PBO; n = 6) was administered. After the basal period, a 4-h metabolic challenge followed, where glucagon (3×-basal), epinephrine (5×-basal), and insulin (2×-basal) concentrations were increased. Hepatic glucose fluxes did not differ between groups during the basal period. In response to the metabolic challenge, hepatic glucose production was stimulated in PBO, resulting in hyperglycemia such that exogenous glucose was required in HSD-I (P < 0.05) to match the glycemia between groups. Net hepatic glucose output and endogenous glucose production were decreased by 11β-HSD1 inhibition (P < 0.05) due to a reduction in net hepatic glycogenolysis (P < 0.05), with no effect on gluconeogenic flux compared with PBO. In addition, glucose utilization (P < 0.05) and the suppression of lipolysis were increased (P < 0.05) in HSD-I compared with PBO. These data suggest that inhibition of 11β-HSD1 may be of therapeutic value in the treatment of diseases characterized by insulin resistance and excessive hepatic glucose production.

Solid-organ transplantation in older adults: current status and future research

An increasing number of patients older than 65 years are referred for and have access to organ transplantation, and an increasing number of older adults are donating organs. Although short-term outcomes are similar in older versus younger transplant recipients, older donor or recipient age is associated with inferior long-term outcomes. However, age is often a proxy for other factors that might predict poor outcomes more strongly and better identify patients at risk for adverse events. Approaches to transplantation in older adults vary across programs, but despite recent gains in access and the increased use of marginal organs, older patients remain less likely than other groups to receive a transplant, and those who do are highly selected. Moreover, few studies have addressed geriatric issues in transplant patient selection or management, or the implications on health span and disability when patients age to late life with a transplanted organ. This paper summarizes a recent trans-disciplinary workshop held by ASP, in collaboration with NHLBI, NIA, NIAID, NIDDK and AGS, to address issues related to kidney, liver, lung, or heart transplantation in older adults and to propose a research agenda in these areas.

Association between genetic variants in adhesion molecules and outcomes after hematopoietic cell transplants

Allogeneic hematopoietic cell transplant (HCT) is associated with a high morbidity and mortality. Adhesion molecules play an important role in endothelial activation and initiation of inflammatory response. We hypothesized that single nucleotide polymorphisms (SNPs) in the endothelial molecules may contribute to heterogeneity in HCT outcomes. We evaluated the association of 4 SNPs in ICAM1 (rs5498), PECAM1 (rs668 and rs1131012) and SELL (rs2229569) genes with acute and chronic graft-versus-host disease (GvHD) and those experiencing transplant-related mortality (TRM) within 1 year among 425 allogeneic HCT recipient-donor pairs. Using a Fine and Gray proportional hazards model to evaluate the association between genetic variants and clinical outcomes, after adjustment for recipient age, race, diagnosis, disease status, gender mismatch, cytomegalovirus serostatus, gender, donor type, conditioning regimen and year of transplant, only rs5498 in the ICAM1 gene among both recipients and donors was associated with a decreased risk of TRM (P ≤ 0.02). None of the SNPs were associated with acute or chronic GvHD risk. These findings suggest that genetic variants in the vascular adhesion molecules may be used to identify patients at high risk for TRM.

Medical Oncology Breast Cancer Quality Indicators: Adherence by the Florida Initiative for Quality Cancer Care (FIQCC) Consortium

Background: The Florida Initiative for Quality Cancer Care (FIQCC) is comprised of 11 practice sites across the state that participate in a comprehensive review of quality of care specific to cancer patients across many disease sites. Quality indicators were scripted based on accepted QOPI, NCCN, ACOS, and site-specific PI panel consensus indicators for breast cancer (BRCA) patients. An evaluation was performed to assess adherence to the performance indicators across sites within the FIQCC.Methods: Comprehensive chart reviews were conducted for all patients with BRCA first seen in 2006 by a medical oncologist at one of the 11 FIQCC sites (3 academic/8 community). Quality measures included: 1) documentation of menopausal status; 2) documentation of receptor status in the chart and evidence that it guided treatment recommendations accordingly; 3) documentation that consent for chemotherapy was obtained; 4) documentation of the planned chemotherapy regimen; and 5) documentation that chemotherapy started within 8 weeks of surgery. A pilot measure included: 6) documentation of fertility preservation being addressed in pre-menopausal women. Pearson's Chi-square test was used to test variability on the quality measurements across practice sites.Results: Charts of 622 patients (99% female), median age of 60 years (range 22-95) were reviewed. Menopausal status was documented in 49% (307/622). Documentation of the receptor status (ER/PR/ Her2Neu) was excellent, 99% (532/537). For those with ER/PR positive, non-metastatic disease measuring at least 1cm, 98% (432/441) were considered for an aromatase inhibitor or tamoxifen within one year of diagnosis. For patients with Stage II-III BRCA with over-expression of Her2Neu (H2N), consideration or administration of trastuzumab was documented in 82% (95/116). With respect to chemotherapy, there was documentation of consent in 75% (247/330), planned chemotherapy regimen in 75% (226/302), and initiation of chemotherapy with 8 weeks of surgery in 84% (233/279). Fertility preservation was only addressed in 11% (10/88) of patients who were documented as pre-menopausal. A statistically significant difference (p&lt; 0.05) across the sites was found for all quality indicators above, except two: documentation of consideration or administration of trastuzumab and discussions of fertility preservation.Discussion: The FIQCC allows for the identification of the need for quality improvements in multiple aspects of breast cancer care. Findings based on 2006 cases identified need for improvements in documentation and consenting for chemotherapy, reporting of menopausal status, consideration and administration of trastuzumab, and consideration of fertility counseling. These findings are now being used at the participating institutions to guide quality improvement efforts.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 1078.

Comparison of two mycophenolate mofetil dosing regimens after hematopoietic cell transplantation

Mycophenolic acid (MPA) is the active component of mycophenolate mofetil (MMF). Low MPA exposure is associated with a higher incidence of acute GVHD and possibly worse engraftment. Therapeutic plasma targets have been proposed in hematopoietic cell transplantation (HCT), however, are difficult to achieve in adult patients with MMF doses of 2 g/day. Mycophenolate pharmacokinetics was prospectively studied in adults undergoing nonmyeloablative HCT who received MMF 3 g/day with CYA. The first 15 individuals received 1.5 g every 12 h and the second 15 received 1 g every 8 h. Sampling was performed in each patient with i.v. and oral administration. There were no differences in total or unbound MPA 24-h cumulative area under the curves (AUCs), concentrations at steady state (Css) or troughs between the two dosing regimens (all P>0.01). The previously proposed total MPA Css target of 3 microg/ml and trough >or=1 micro/ml were achieved in only 13-27% and 20-53% of patients, respectively, on 3 g/day. However, the 3 g/day regimens readily achieved satisfactory unbound 24-h cumulative AUC targets of 0.600 microg(*)h/ml in 87-100% of subjects. There appears to be no significant difference in daily MPA exposure when MMF of 3 g/day is divided into two or three equal doses.

Stimulation of cholecystokinin-A receptors with GI181771X does not cause weight loss in overweight or obese patients

Cholecystokinin (CCK) decreases meal size through activation of CCK-A receptors on vagal afferents. We tested the hypothesis that the selective CCK-A agonist GI181771X induces weight loss in obese patients. Patients with body mass index > or = 30 or > or = 27 kg/m2 with concomitant risk factors were randomized to 24-week, double-blind treatment with different GI181771X doses or matching placebo together with a hypocaloric diet. The primary efficacy end point was the absolute change in body weight. To monitor pancreatic and gallbladder effects, patients underwent abdominal ultrasound and magnetic resonance imaging before and after treatment. We randomized 701 patients to double-blind treatment. GI181771X did not reduce body weight and had no effect on waist circumference or other cardiometabolic risk markers. Gastrointestinal side effects were more common with GI181771X than with placebo treatment, whereas hepatobiliary or pancreatic abnormalities did not occur. CCK-A by itself does not have a central role in long-term energy balance.

Factors affecting the pharmacokinetics of tacrolimus (FK506) in hematopoietic cell transplant (HCT) patients

Tacrolimus is an immunosuppressant commonly used in the prevention of graft-versus-host disease (GVHD) following allogeneic HCT. Unfortunately, the use of tacrolimus is associated with variable immunosuppression and toxicity. The purpose of this study was to describe tacrolimus population pharmacokinetic parameters, to identify relationships between clinical covariates and pharmacokinetic estimates, and to develop a model to predict tacrolimus clearance in HCT patients. Steady-state whole blood tacrolimus concentrations (n = 1625) obtained during intravenous and oral therapy were analyzed in 122 patients. Population clearance (CL) was 5.22 l/h and bioavailability (F) was 0.28. The influence of clinical covariates on population estimates of CL and F of tacrolimus were tested with nonlinear mixed effects models (NONMEM). CL was significantly reduced by elevations in total bilirubin 2.0-9.9 mg/dl (CL * 0.797), bilirubin > or = 10 mg/dl (CL * 0.581), serum creatinine > or = 2 mg/dl (CL * 0.587), grade III/IV graft-versus-host disease (CL * 0.814) and veno-occlusive disease (CL 0.814). No covariates were predictive of oral F. The interindividual variabilities in CL and F were 33% and 44%, respectively. Residual variability was 27.5% and 16.8% at tacrolimus concentrations of 10 microg/l and 20 microg/l, respectively. These models may be used to predict tacrolimus clearance and doses in adult patients following HCT.

Synthesis and characterization of non-steroidal ligands for the glucocorticoid receptor: selective quinoline derivatives with prednisolone-equivalent functional activity

A novel class of functional ligands for the human glucocorticoid receptor is described. Substituents in the C-10 position of the tetracyclic core are essential for glucocorticoid receptor (GR) selectivity versus other steroid receptors. The C-5 position is derivatized with meta-substituted aromatic groups, resulting in analogues with a high affinity for GR (K(i) = 2.4-9.3 nM) and functional activity comparable to prednisolone in reporter gene assays of glucocorticoid-mediated gene transcription. The biological activity of these novel quinolines was also prednisolone-equivalent in whole cell assays of glucocorticoid function, and compound 13 was similar to prednisolone (po ED(50) = 2.8 mpk for 13 vs ED(50) = 1.2 mpk for prednisolone) in a rodent model of asthma (sephadex-induced eosinophil influx).

Mutations in the preproghrelin/ghrelin gene associated with obesity in humans

Ghrelin and preproghrelin sequences were determined in 96 unrelated female subjects with severe obesity (mean body mass index (BMI) 42.3 +/- 3.4 kg/m(2)) and in 96 non-obese female controls (mean BMI 23.0 +/- 1.4 (kg/m2) of the Swedish Obese Subjects cohort. A mutation at amino acid position 51 (Arg51Gln) of the preproghrelin sequence that corresponds to the last amino acid in mature ghrelin product was identified in six (all heterozygotes) obese subjects (6.3%) but not among controls (p < 0.05). The self-reported weight at 20, 30, and 40 years of age tended to be 7.5, 4.7 and 6.4 kg lower, respectively, among obese Gln allele carriers versus obese non-carriers. In addition, a mutation at codon 72 of the preproghrelin gene (Leu72Met) was detected in 15 obese (12 hetero- and 3 homozygotes) and 12 control (all heterozygotes) subjects. This mutation outside the coding region of the mature ghrelin product tended to be associated with lower age of self-reported onset of obesity (15.6 +/- 7.9 vs. 20.5 +/- 10.5 years; p = 0.09). In addition to these two mutations in coding regions, a G274A base change in a non-coding region between exons one and two was found only in two obese individuals. The Arg51Gln amino acid substitution may alter the cleavage site of endoproteases and the length of the mature ghrelin product. The functional significance of the Leu72Met mutation and a G274A base change remains to be determined. In conclusion, the data provide evidence that a low frequency sequence variation in the ghrelin gene could play a role in the etiology of obesity.

Oral busulfan pharmacokinetics and engraftment in children with Hurler syndrome and other inherited metabolic storage diseases undergoing hematopoietic cell transplantation

Allogeneic hematopoietic cell transplantation (HCT) is the only treatment for selected inherited metabolic storage diseases (IMSD); a significant shortcoming is failure to achieve donor-derived engraftment. This study was undertaken to determine whether busulfan pharmacokinetics (BU PK) are altered in children with IMSD and whether BU concentrations are important in achieving engraftment. BU samples were obtained from 39 IMSD children, including 20 children with Hurler syndrome, undergoing HCT. Patients received oral BU (40 mg/m(2)/dose x 8 doses), cyclophosphamide (60 mg/kg/day x 2 doses) and TBI (750 cGy in one fraction) as a preparative regimen. Median (range) oral clearance corrected for bioavailability (Cl/F in ml/min/kg), area under the curve (AUC in ng min/ml) and BU plasma concentration (Cp in ng/ml) with the fourth dose were 5.2 (2.1-11.4), 318 294 (112 893-640 995) and 950 (314-1780), respectively. Children < 3 years of age had lower AUC and Cp but higher Cl/F (P < or = 0.03). BU Cp (P = 0.06) or marrow cell dose (P = 0.32) was not different in Hurler syndrome compared to other IMSD. A median BU Cp of 959 and 831 ng/ml was achieved in children with full and failed early engraftment, respectively. There was no difference in early and late engraftment between children with Hurler and other IMSD. In conclusion, we found no significant association between engraftment, marrow cell dose and BU exposure when combined with CY and TBI in children with IMSD.

Sharing the mantle of primary female care: physicians, nurse practitioners, and physician assistants

OBJECTIVE

To examine the role that nurse practitioners (NPs) and physician assistants (PAs) play in women's health care as part of a larger study assessing the use of NPs and PAs as primary care practitioners.

METHODS

We conducted qualitative key informant interviews with providers and administrators at nine managed care organizations and multispecialty clinics.

RESULTS

Respondents indicated that although there were a number of reasons these institutions began to hire NPs and PAs, the shortage of women health care providers was an important contributing factor. Many women patients prefer to see same-sex providers, but there are not enough female physicians to meet this demand. NPs and PAs were more interested in preventive care than physicians were. For these reasons, NPs and PAs came to play a central role in the delivery of women's primary care within these institutions.

CONCLUSION

Although the number of female physicians is increasing, there is no indication that the importance of NPs and PAs is waning. Rather, they have become valued members of the health care team. Women physicians will most likely be expected to provide primary care in teams with NPs and PAs.

Tacrolimus: a new agent for the prevention of graft-versus-host disease in hematopoietic stem cell transplantation

Tacrolimus (FK506) is a macrolide lactone with potent immunosuppressive activity 100 times that of cyclosporine by weight. The molecular mechanism of action is mediated via an inhibition of the phosphorylase activity of calcineurin by drug-immunophilin complex, resulting in the inhibition of IL-2 gene expression. There are emerging studies now showing significant efficacy of tacrolimus in GVHD prevention in both related and unrelated donor transplantation. Three multicenter randomized studies comparing tacrolimus to cyclosporine have been completed, one each in related and unrelated donor transplantation; the remaining study involved both related and unrelated donor transplantation. All three studies showed a significantly lower incidence of grade II-IV acute GVHD in patients who received tacrolimus. One study in sibling donor transplantation showed that patients with advanced disease who received tacrolimus had a poorer survival than patients who received cyclosporine, but the survival was similar in patients with non-advanced disease. The remaining two studies, one in unrelated donors and the other combining both related and unrelated donors did not show any survival difference between the tacrolimus and cyclosporine groups. In addition, this review also highlights some of the critical questions regarding the role of this agent in allogeneic stem cell transplantation: (1) the contribution of methotrexate in combination with tacrolimus; (2) the starting i.v. dose of tacrolimus; (3) the suggested whole blood level of tacrolimus and its effect on nephrotoxicity; and (4) whether tacrolimus should be used in patients with advanced malignancy. Future studies using tacrolimus in combination with other immunosuppressants, and its use in patients with advanced malignancy will be warranted.

Tacrolimus and methotrexate for the prophylaxis of acute graft-versus-host disease in allogeneic bone marrow transplantation in patients with hematologic malignancies

We conducted a study to evaluate the efficacy of the combination of tacrolimus and short-course methotrexate for the prevention of acute GVHD in patients with hematologic malignancies. Patients received preparative regimens specific for their disease category. Twenty-six out of 28 received HLA-identical sibling transplants and the two remaining patients received one-antigen mismatched transplants from a family member. With a median follow-up of 14 months, the Kaplan-Meier estimate of event-free survival was 50 +/- 9%. The probability of grade II-IV GVHD was 15 +/- 7%. Four patients developed GVHD: two had grade II and one each developed grade III and IV GVHD. Administration of methotrexate was associated with severe mucositis and there was no correlation between the distribution of the GVHD grade and the cumulative dose of methotrexate given. Thirteen patients have died; nine from transplant-related complications and four from relapse. The major toxicity of tacrolimus was renal. Nine out of 28 patients (32%) developed renal dysfunction attributed to tacrolimus. The combination of tacrolimus and methotrexate is an effective regimen for GVHD prophylaxis but associated with significant renal and mucosal toxicity. Further studies of tacrolimus as a single agent or in combination with either steroids or with a lower dose of methotrexate or with other antiproliferative drugs to modify the adverse events may improve the therapeutic index of this useful and promising agent.

Predictive ability of creatinine clearance estimate models in pediatric bone marrow transplant patients

The predictive performance of estimating creatinine clearance (CrCl) with pediatric clearance models was evaluated. Thirty-two pediatric patients with stable renal function between the ages of 1 and 14 years about to undergo bone marrow transplantation (BMT) who had 12-24 h urine collections for measurement of CrCl were studied. The measured CrCl was compared to CrCls calculated from seven models used to estimate CrCl in the pediatric population. The models used were Traub and Johnson, Schwartz et al, Counahan et al, modified Counahan et al, Ghazali and Barratt, Shull et al and Dechaux et al. Coefficients of determination (r2) between measured and estimated CrCls from models 1 to 7 were 0.47, 0.47, 0.47, 0.49, 0.47, 0.52, 0.47. The mean absolute percent errors for the models were 23.2-45.2%. In the majority of children, models overestimated CrCl. The tested models did not accurately predict CrCl and did not provide a reliable alternative to measured CrCl.

A double-blind trial of haloperidol, chlorpromazine, and lorazepam in the treatment of delirium in hospitalized AIDS patients

OBJECTIVE

The purpose of this study was to examine the efficacy and side effects of haloperidol, chlorpromazine, and lorazepam for the treatment of the symptoms of delirium in adult AIDS patients in a randomized, double-blind, comparison trial.

METHOD

Nondelirious, medically hospitalized AIDS patients (N = 244) consented to participate in the study and were monitored prospectively for the development of delirium. Patients entered the treatment phase of the study if they met DSM-III-R criteria for delirium and scored 13 or greater on the Delirium Rating Scale. Thirty patients were randomly assigned to treatment with haloperidol (N = 11), chlorpromazine (N = 13), or lorazepam (N = 6). Efficacy and side effects associated with the treatment were measured with repeated assessments using the Delirium Rating Scale, the Mini-Mental State, and the Extrapyramidal Symptom Rating Scale.

RESULTS

Treatment with either haloperidol or chlorpromazine in relatively low doses resulted in significant improvement in the symptoms of delirium as measured by the Delirium Rating Scale. No improvement in the symptoms of delirium was found in the lorazepam group. Cognitive function, as measured by the Mini-Mental State, improved significantly from baseline to day 2 for patients receiving chlorpromazine. Treatment with haloperidol or chlorpromazine was associated with an extremely low prevalence of extrapyramidal side effects. All patients receiving lorazepam, however, developed treatment-limiting adverse effects. Although only a small number of patients had been treated with lorazepam, the authors became sufficiently concerned with the adverse effects to terminate that arm of the protocol early.

CONCLUSIONS

Symptoms of delirium in medically hospitalized AIDS patients may be treated efficaciously with few side effects by using low-dose neuroleptics (haloperidol or chlorpromazine). Lorazepam alone appears to be ineffective and associated with treatment-limiting adverse effects.

Stability of isradipine in an extemporaneously compounded oral liquid

The stability of isradipine in an extemporaneously compounded oral liquid was studied. A suspension was prepared from the powder of commercially available 5-mg isradipine capsules and sufficient Simple Syrup, NF, to make a final volume of 50 mL. A control suspension was prepared from analytical-grade isradipine powder and Simple Syrup, NF. The final concentration of isradipine in both suspensions was 1 mg/mL. Three identical volumes of each suspension were stored in 2-oz amber glass prescription bottles, which were stored at 4 degrees C. Immediately after preparation and at 7, 16, 22, 28, and 35 days, samples were visually inspected and assayed in duplicate by high-performance liquid chromatography; the pH of the samples was also determined. At least 95% of the initial isradipine concentration remained throughout the study period in all samples of both suspensions. Color, odor, and pH did not change appreciably. Isradipine 1 mg/mL in an oral liquid compounded from Simple Syrup, NF, and powder from capsules was stable for at least 35 days in amber glass bottles at 4 degrees C.

Anti-inflammatory properties of the protein kinase C inhibitor, 3-[1-[3-(dimethylamino)propyl]-1H-indol-3-yl]-4-(1H-indol-3-yl)-1H- pyrrole-2,5-dione monohydrochloride (GF109203X) in the PMA-mouse ear edema model

Protein kinase C (PKC) mediates a number of intracellular signal transduction pathways implicated in the pathogenesis of inflammation, including phospholipase A2-dependent arachidonic acid release and eicosanoid production. Recent studies demonstrate that the PKC inhibitor GF109203X significantly reduces a number of inflammatory processes resulting from PKC activation by the topical application of phorbol myristate acetate (PMA) to mouse ears. In this model, GF109203X significantly reduced edema at doses similar to the PKC inhibitor staurosporine, and more effectively than indomethacin, zileuton, or sodium meclofenamate. Histological and biochemical analysis of biopsies from control and drug-treated ears revealed a marked reduction in edema, infiltrating neutrophils, and levels of the neutrophil-specific marker, myeloperoxidase, in GF109203X-treated mice. Prostaglandin E2 levels were also reduced in ears treated with GF109203X. These data suggest that GF109203X is an effective antiinflammatory agent as evaluated in the PMA model of edema, and implicates PKC as a potential target in the development of novel anti-inflammatory agents.

A novel semi-automated paramagnetic microparticle based enzyme immunoassay for hepatitis C virus: its application to serologic testing

A new rapid serologic enzyme immunoassay for antibodies to hepatitis C virus (HCV) is described. The assay combines synthetic peptide and recombinant antigens representing putative structural and non structural HCV gene products with paramagnetic microparticle assay (MP assay) technology. Assay readout is based upon an enzymatically generated fluorescent product which is quantified with a novel semi-automated washer/reader instrument system. Assay sensitivity and specificity was determined to be greater than the first generation HCV C-100 EIA using a non-A, non-B hepatitis disease panel, an HCV performance panel, an HCV seroconversion panel, dilutions of HCV reactive sera, and random volunteer blood donor specimens.

Stability of fluconazole and amino acids in parenteral nutrient solutions

The stability of fluconazole and amino acids in parenteral nutrient (PN) solutions was studied. Amino acids at three concentrations (1.0%, 2.5%, and 5.0%) with 25% dextrose injection were combined with a high (1.75 mg/mL) or a low (0.5 mg/mL) concentration of fluconazole to form six combinations of PN solution and fluconazole. The solutions were visually inspected for precipitate, color change, or gas formation and tested for pH. By using high-performance liquid chromatography, the solutions were assayed for fluconazole concentration at zero, one, and two hours after preparation. The PN solution containing fluconazole 1.75 mg/mL and 5.0% amino acids was assayed for 14 amino acids at the same time points. There was no visual evidence of incompatibility in any of the fluconazole and PN solutions, and the pH of the solutions did not vary appreciably throughout the study period. The mean percentage of initial fluconazole concentration remaining at one and two hours was greater than 97% for all of the solutions studied. The mean percentage of initial amino acid concentration remaining at one and two hours was greater than 93% for each of the 14 amino acids assayed. When fluconazole 0.5 mg/mL or 1.75 mg/mL is mixed with PN solution containing 1.0%, 2.5%, or 5.0% amino acids and 25% dextrose injection, both fluconazole and amino acids are stable for up to two hours.

Secondary structures of rat lipolytic enzymes: circular dichroism studies and relation to hydrophobic moments

To explore the secondary structures of lingual and pancreatic lipases, circular dichroism measurements were performed. Maximum average ellipticities were used to calculate the percentage of alpha-helices, beta-sheets, and random coils. Lingual lipase had an ellipticity of -20235 +/- 140 deg cm2/dmol (mean +/- SE) at 220 nm suggesting 60% alpha-helix, 20% beta-sheet and 20% random coil structure, but the mean ellipticity for pancreatic lipase was -14093 +/- 82 deg cm2/dmol (mean +/- SE) at 210 nm suggesting a 34.8% alpha-helical, 25% beta-sheet and 40% random coil secondary structure. An alpha-helical stretch of residues with a large hydrophobic moment ("globular" alpha-helix by hydrophobic moment plot) from amino acids 382 through 389 at the COOH-terminal end of lingual lipase was noted. This sequence, absent in pancreatic lipase, may account for the avid binding of lingual lipase to fat emulsion particles.

Advantages and disadvantages of various upper and lower rate responses

The advantages and disadvantages of several types of upper and lower rate responses are presented. The optimal response is dependent upon the programmable parameters and the relationship to natural cardiac cycles. The ideal physiologic pacemaker will provide several different choices for rate response. In addition, it will provide the physician with the means to verify the physiologic effects of the particular response.

Ultrasound of renal sinus: new observations

Technical factors and diagnostic criteria that permit discrimination among diseases of the renal sinus are described. Because the size of the collecting system changes with the state of hydration, a standard approach permits optimal comparison of examinations performed on different occasions. A fluid challenge is indicated if relative or partial obstruction is suspected. Ureteric compression permits optimal delineation of the collecting system but is indicated only in selected situations. Both tumor and blood clot within the renal sinus appear as echogenic masses without a significant acoustic shadow. Serial ultrasound studies demonstrate the resolution of the blood clot. Both in vivo and in vitro studies of renal stones demonstrate that the acoustic shadow of nephrolithiasis is best seen with low gain and with the stone within the focal zone of the transducer.

Lack of an acoustic shadow on scans of gallstones: a possible artifact

The high attenuation of gallstones results in the formation of an acoustic shadow on the ultrasound scan. Such shadows are best seen when the stone lies within the focal zone of the transducer and is large in comparison to the beam width or wavelength employed. Inadequecies in the dynamic range of available TV display units necessitate the use of compression-amplification signal processing which may preclude perception of such a shadow and seriously interfere with diagnostic accuracy.