A solid phase extraction-liquid chromatographic-tandem mass spectrometry method for determination of concentrations of GDC-0941, a small molecule class I phosphatidylinositide 3-kinase inhibitor, to support clinical development

A solid phase extraction (SPE) liquid chromatographic-tandem mass spectrometry (LC-MS/MS) method for the determination of GDC-0941 concentrations in human plasma has been developed and validated to support clinical development. An Oasis MCX 10mg 96-well SPE plate was used to extract plasma samples (50 μL) and the resulting extracts were analyzed using reverse-phase chromatography and mass spectrometer coupled with a turbo-ionspray interface. The method was validated over the calibration curve range 0.500-500 ng/mL with linear regression and 1/x(2) weighting. Within-run relative standard deviation (%RSD) ranged from 1.5 to 11.5%, while the between-run %RSD varied from 0.0 to 4.4%. The accuracy ranged from 96.0% to 110.0% of nominal for within-run and 98.0% to 108.0% of nominal for between-run at all concentrations including the LLOQ quality control at 0.500 ng/mL. Extraction recovery of GDC-0941 was between 79.0% and 86.2%. Stability of GDC-0941 was established in human plasma for 602 days at -70 °C and 598 days at -20°C, respectively, and established in reconstituted sample extracts for 167 h when stored at room temperature. Internal standard normalized matrix factor was 1.1, demonstrating that the use of the stable-labeled internal standard GDC-0941-d(8) effectively compensated observed matrix effect and resulting in no adverse impact on the quality of the data produced. This assay was used for the determination of GDC-0941 human plasma concentrations over a sufficient time period to determine pharmacokinetic parameters at relevant clinical doses.

MR image-guided investigation of regional signal transducers and activators of transcription-1 activation in a rat model of focal cerebral ischemia

BACKGROUND AND PURPOSE

STAT-1 is a member of a family of proteins called signal transducers and activators of transcription (STATs), and recent studies have shown its involvement in the induction of apoptosis. There is limited information on the role of STAT-1 following stroke. In this study we use MRI measurements of cerebral perfusion and bioenergetic status to target measurements of regional STAT-1 activity.

METHODS

Rats were subjected to 60 or 90 min of middle cerebral artery occlusion with and without reperfusion. MRI maps of the apparent diffusion coefficient of water and cerebral blood flow were acquired throughout the study. After the ischemia or reperfusion period, the brain was excised and samples were analyzed by Western blots using anti-phospho-STAT1 and anti-Fas antibodies. Regions were selected for analysis according to their MRI characteristics.

RESULTS

Transcriptional factor STAT-1 was enhanced in the lesion core and, to a lesser extent, in the lesion periphery, following ischemia and reperfusion. This level of activity was greater than for ischemia alone. Western blots demonstrated STAT-1 phosphorylation on tyrosine 701 and not serine 727 after ischemia and 3 h of reperfusion. Enhanced expression of the apoptotic death receptor Fas was confirmed after ischemia followed by reperfusion.

CONCLUSIONS

This study demonstrates that focal ischemia of the rat brain can induce STAT-1 activation, particularly following a period of reperfusion. The activation occurs not only in the lesion core, but also in the lesion periphery, as identified using MRI. STAT-1 may play an important role in the induction of cell death following stroke.

Financial managers' costing expertise is needed in clinical trials

In addition to providing comparable and verifiable evidence regarding outcomes, clinical trials could also serve as sources of accurate and replicable financial information. Trial reports that identify expenses associated with effective diagnostic and therapeutic interventions enable cost controls. Standardized cost calculations could help clinicians and administrators identify more efficient health care technologies. Unfortunately, relatively few published trials include economic analyses and when they do, data are incomplete. Based on analyses of 97 clinical trial reports, this article proposes a standard costing format. Health care financial managers have the costing expertise necessary to implement and interpret standardized cost calculations for clinical trials. With the active involvement of financial managers, a standard costing format for clinical trials can be achieved.

Role of hepatic non-parenchymal cells in the response of rat hepatocytes to the peroxisome proliferator nafenopin in vitro

Induction of liver cancer by peroxisome proliferators such as nafenopin is frequently associated with increased liver growth, increased DNA synthesis and suppression of apoptosis. The cytokine, tumour necrosis factor alpha (TNF alpha), and non-parenchymal liver cells have been implicated in mediating the hepatic response to peroxisome proliferators. Here, we have investigated the dependency of the hepatocyte response to peroxisome proliferators on non-parenchymal cells, a major source of hepatic cytokines. Addition of non-parenchymal cells, or conditioned medium from non-parenchymal cell cultures, increased DNA synthesis (220% and 270% of control, respectively) and suppressed transforming growth factor beta(1)-induced hepatocyte apoptosis (32% and 54% of control, respectively). Removal of non-parenchymal cells from normal hepatocyte cultures prevented both the nafenopin- and TNF alpha-induced increase in DNA synthesis and suppression of hepatocyte apoptosis; this response was restored by returning non-parenchymal cells to the purified hepatocytes. TNF alpha was detected in the medium of non-parenchymal cell (3-15 pg/ml) and normal hepatocyte cultures (25-100 pg/ml) by bioassay using L929 cells. However, the contribution of TNF alpha released from non-parenchymal cells was small compared with that released spontaneously by hepatocytes. Nafenopin significantly increased the release of TNF alpha from non-parenchymal cells to 56 +/- 18 pg/ml, but had little effect on TNF alpha release by hepatocytes. However, the concentration of exogenous TNF alpha required to elicit a response in hepatocytes was 100 pg/ml and above. These data provide evidence that hepatic non-parenchymal cells are permissive for the growth response of hepatocytes in vitro to peroxisome proliferators and this may be mediated, at least in part by TNF alpha. However, the levels of TNF alpha released spontaneously or in response to peroxisome proliferators are insufficient per se to induce a growth response.

Effect of vasovasostomy on contralateral testicular damage associated with unilateral vasectomy in mature and immature Lewis rats

OBJECTIVE

We sought to determine if laser-assisted vasovasostomy could reverse the contralateral histologic testicular changes associated with unilateral vasectomy.

DESIGN

A prospective, randomized, blinded, controlled study.

SETTING

Animal microsurgical laboratory, St. John's Mercy Medical Center, St. Louis, Missouri.

PATIENT(S)

Twenty mature and 20 immature male Lewis rats.

INTERVENTION(S)

Ten mature and 10 immature male Lewis rats underwent unilateral vasectomy. At 5 months, testicular biopsy and laser-assisted vasovasostomies were performed followed 2 months later by evaluation of vas patency and repeat testicular biopsy. Control animals consisted of 10 rats in each group, 5 that underwent sham operations and 5 that had halothane anesthesia alone.

RESULT(S)

In the immature and mature groups unilateral vasectomy resulted in marked contralateral testicular damage in 30% (3 of 10) and 50% (5 of 10), respectively. Vas patency determined 2 months after vasovasostomy was 80% (8 of 10) in the mature group and 89% (8 of 9) in the immature group. No animal that had contralateral testicular changes after vasectomy and a patent vas after vasovasostomy showed improvement in testicular histology.

CONCLUSION(S)

It appears that contralateral testicular damage associated with unilateral vasectomy is not improved 2 months after successful vasovasostomy in mature or immature Lewis rats.

Role for tumor necrosis factor alpha receptor 1 and interleukin-1 receptor in the suppression of mouse hepatocyte apoptosis by the peroxisome proliferator nafenopin

Peroxisome proliferators (PPs) cause rodent liver enlargement and tumors. In vitro, PPs induce rat and mouse hepatocyte DNA synthesis and suppress apoptosis, a response mimicked by exogenous tumor necrosis factor alpha (TNFalpha). Here, we determine the role of TNF receptor 1 (TNFR1), TNF receptor 2 (TNFR2), and nuclear factor kappa beta (NFkappaB) in the response of mouse hepatocytes to the PP, nafenopin. Nafenopin (50 micromol/L) induced DNA synthesis as measured by bromodeoxyuridine (BrdU) incorporation, suppressed cell death as measured by Hoechst 33258 staining, induced peroxisomal beta-oxidation as measured by cyanide insensitive palmitoyl CoA oxidation (PCO) and caused activation of nuclear factor kappa beta (NFkappaB) as determined by electrophoretic mobility gel shift assay (EMSA). The induction of DNA synthesis and the suppression of apoptosis in response to nafenopin was abrogated completely by blocking antibodies to TNFR1 but not to TNFR2. In contrast, the induction of peroxisomal beta-oxidation by nafenopin was not blocked by the anti-TNFR1 antibody. Next, we evaluated the response of hepatocytes to interleukin-1 (IL-1), another proinflammatory cytokine. IL-1alpha (2.5 ng/mL) and, to a lesser extent, IL-1beta (5 ng/mL), shared the ability of TNFalpha to induce DNA synthesis and suppress apoptosis. In addition, anti-IL-1 receptor, type 1/p80 (IL-1R) antibodies were able to abrogate the response to nafenopin. IL-1alpha was still able to perturb hepatocyte growth in the presence of the anti-TNFR1 antibody suggesting that IL-1alpha acts independently rather than by elaborating TNFalpha. In summary, these data provide additional evidence for a role for hepatic cytokines in the perturbation of hepatocyte growth by PPs such as nafenopin.

Laparoscopic v laparoscopy-assisted donor nephrectomy in the porcine model

PURPOSE

Laparoscopic donor nephrectomy is an established procedure in the porcine model. We sought to compare intraoperative variables between live laparoscopic (LAP) and laparoscopy-assisted (LAP-A) donor nephrectomy.

MATERIALS AND METHODS

Eight domestic pigs underwent either traditional laparoscopic donor nephrectomy (N = 4) or laparoscopy-assisted donor nephrectomy (N = 4) using the Pneumosleeve followed by conventional heterotopic autotransplantation.

RESULTS

No significant differences were noted between the groups with regard to vessel length, ureteral length, or postoperative urine output. The operating room time was 108+/-12 minutes in the LAP group v 75.8+/-10.3 minutes in the LAP-A group (P = 0.0065). Although the difference was not statistically significant, warm ischemic time, tended to be lower in the LAP-A than the LAP group: 70+/-3.0 seconds v 135+/-57 seconds, respectively (P = 0.059). Graft survival was identical in the two groups.

CONCLUSION

Laparoscopy-assisted (via Pneumosleeve) live donor nephrectomy shortens the operative time without affecting graft survival in the domestic swine model.

Role of chronic catheterization in the development of bladder cancer in patients with spinal cord injury

OBJECTIVES

Patients with spinal cord injury (SCI) and chronic indwelling catheters are known to be at increased risk of bladder malignancy. "Decatheterization" by clean intermittent catheterization, external condom catheterization, or spontaneous voiding is thought to reduce the risk by decreasing the chronic mucosal irritation and rate of infection. We examined two Department of Veterans Affairs (DVA) data bases to test this theory.

METHODS

A population-based retrospective analysis of invasive treatments for carcinoma of the bladder in all DVA hospitals was conducted using computerized inpatient files from fiscal years 1988 to 1992.

RESULTS

One hundred thirty patients with bladder malignancy were identified from a pool of 33,565 patients with SCI (0.39%). All 130 patients underwent either radical cystectomy (n = 63, 48%) or transurethral resection of bladder tumor (n = 67, 52%). The 30-day perioperative mortality and overall 5-year survival rates were 2 (1.5%) and 49 (38%) of 130, respectively. Of the 130 patients analyzed, 42 (32%) had adequate data available regarding tumor pathologic findings and method of bladder management for analysis. The average age at diagnosis was 57.3 years. The histologic finding was transitional cell carcinoma in 23 (55%), squamous cell carcinoma in 14 (33%), and adenocarcinoma in 4 (10%) of 42. Bladder management was an indwelling urethral catheter in 18 (43%), suprapubic catheter in 8 (19%), clean intermittent catheterization in 8 (19%), and condom catheter in 6 (14%) of 42 patients. Squamous cell carcinoma was more common in patients with indwelling urethral catheters and suprapubic tubes (11 of 26, 42%) than in those using clean intermittent catheterization, condom catheterization, or spontaneous voiding (3 of 16, 19%).

CONCLUSIONS

Bladder cancer was diagnosed in approximately 0.39% of this large SCI population during a 5-year period. Most cancers (55%) were transitional cell carcinomas. Squamous cell carcinoma was more common in patients with SCI and indwelling catheters than those without chronic catheterization. These data continue to suggest that avoidance of indwelling catheters, when feasible, is the preferred method of bladder management in patients with SCI.

Managing capital and administrative (indirect) costs to achieve strategic objectives: the dialysis clinic versus the outpatient clinic

During the race for costing accuracy in health care, managers should acknowledge the equal importance of interdepartmental relations. Although newer costing systems can produce more accurate numbers, greater costing accuracy may not always strengthen the organization. This article demonstrates that subsidizing some capital and administrative (indirect) costs for select hospital departments may help to achieve strategic management objectives.

Interpreting cost analyses of clinical interventions

OBJECTIVE

In the present era of cost containment, physicians need reliable data about specific interventions. The objectives of this study were to assist practitioners in interpretation of economic analyses and estimation of their own costs of implementing recommended interventions.

DATA SOURCES

MEDLINE search from 1966 through 1995 using the text words cost or expense and medical subject heading (MeSH) terms costs and cost analysis, cost control, cost of illness, cost savings, or cost-benefit analysis.

STUDY SELECTION

The 4 eligibility criteria were clinical trial with random assignment; health care quality improvement intervention tested; effects measured on the process or outcome of care; and cost calculation mentioned in the report.

DATA EXTRACTION

After independent abstraction and after consensus development, financial data were entered into a costing protocol to determine which costs related to the intervention were provided.

DATA SYNTHESIS

Of 181 articles, 97 (53.6%) included actual numbers on the costs of the intervention. Of 97 articles analyzed, the most frequently reported cost figures were in the category of operating expenses (direct cost, 61.9%; labor, 42.3%; and supplies, 32.0%). General overhead was not presented in 91 (93.8%) of the 97 studies. Only 14 (14.4%) of the 97 studies mentioned start-up costs. The text word $ in the abstract and the most useful MeSH index term of cost-benefit analysis appeared with nearly equal frequency in the articles that included actual cost data (37.1 % vs 35.1%). Two thirds of articles indexed with the MeSH term cost control did not include cost figures.

CONCLUSIONS

Statements regarding cost without substantiating data are made habitually in reports of clinical trials. In clinical trial reports presenting data on expenditures, start-up costs and general overhead are frequently disregarded. Practitioners can detect missing information by placing cost data in a standardized protocol. The costing protocol of this study can help bridge care delivery and economic analyses.

Development of a malignant peripheral nerve sheath tumor following treatment for testicular seminoma

A novel case is reported in which an S2 nerve root malignant peripheral nerve sheath tumor was diagnosed approximately 8 years after treatment for Stage I testicular seminoma. This patient underwent right orchiectomy and subsequent irradiation therapy to the periaortic region, including the sacrum. Postoperative radiation therapy likely played a role in the development of this second malignancy.

Contrasting RCC, RVU, and ABC for managed care decisions. A case study compares three widely used costing methods and finds one superior

To obtain cost data needed to improve managed care decisions and negotiate profitable capitation contracts, most healthcare provider organizations use one of three costing methods: the ratio-of-costs-to-charges method, the relative value unit method, or the activity-based costing method. Although the ratio-of-costs to charges is used by a majority of provider organizations, a case study that applied these three methods in a renal dialysis clinic found that the activity-based costing method provided the most accurate cost data. By using this costing method, healthcare financial managers can obtain the data needed to make optimal decisions regarding resource allocation and cost containment, thus assuring the longterm financial viability of their organizations.

Profitable capitation requires accurate costing

In the name of costing accuracy, nurses are asked to track inventory use on per treatment basis when more significant costs, such as general overhead and nursing salaries, are usually allocated to patients or treatments on an average cost basis. Accurate treatment costing and financial viability require analysis of all resources actually consumed in treatment delivery, including nursing services and inventory. More precise costing information enables more profitable decisions as is demonstrated by comparing the ratio-of-cost-to-treatment method (aggregate costing) with alternative activity-based costing methods (ABC). Nurses must participate in this costing process to assure that capitation bids are based upon accurate costs rather than simple averages.

New disability rights require organizational change and leadership

On July 26, 1990, President George Bush signed the Americans with Disabilities Act (ADA). This legislation has been referred to as the "emancipation proclamation for the disabled" because of its great importance to persons with disabilities in our society. The ADA will not be implemented in a substantive way, however, without truly transformative leadership. Because of their traditional role in this area, health care professionals are in a unique position to provide that leadership and to help effect the necessary organizational changes. Passage of the ADA is only the beginning; the true test of its success will be in its implementation.

Financial effect of clinical decisions: case study of a dialysis center

The purpose of this study was to specify the financial effect of clinical decisions in a dialysis center. A consecutive sample of 14,343 outpatient hemodialysis treatments (OHD), 16,111 continuous ambulatory peritoneal dialysis (CAPD), and 4,513 chronic cycler-assisted peritoneal dialysis (CCPD) days of treatment was analyzed. An activity-based cost calculation method was applied to the analysis of alternative treatments (service bundles). The weekly cost of OHD was higher ($338 versus $241/$242), and the contribution margin (reimbursement minus total cost) of CAPD/CCPD was much greater ($.48 versus $148/$147 per patient week). Clinical decision-making had an influence on less than 6.8% of OHD and 45.4%/46.6% of CAPD/CCPD related expenses. In comparison to activity-based cost calculation, conventional methods overestimated the overhead expense of CAPD by 3-48%. This study documented that most cost control opportunities reside in the usual process of care and less can be influenced by a direct interference with the patient-physician contacts. Paying for 1 week of renal replacement (capitation) could simplify the process of reimbursement and cost tracking.

The Columbia Registry of Information and Utilization Management Trials

OBJECTIVE

T systematically locate, register, and abstract information used in comparing effects of various information services (computerized and noncomputerized) and utilization management interventions on the process and outcome of patient care.

DESIGN

Manual and electronic database searches located reports that met three main criteria: 1) randomized controlled trial; 2) information or utilization management intervention in the study group with no similar intervention in the control group; and 3) effect of the intervention on the process and/or outcome of patient care had been measured. Published reports were registered in the Columbia Registry.

RESULTS

Nearly 600 reports were collected from 24 countries and 189 different publications. Frequently tested interventions included patients or physician education, telephone follow-up, patient or physician reminders, and home care services. Frequently reported effect variables included hospitalization rate, length of stay, immunization rate, and mortality rate. Standardized formal tools were developed for the separation and abstraction of practical information and methodologic details from the collected trial reports.

CONCLUSIONS

The registry provides a new source of information for meta-analyses, traditional reviews, and executive summaries of quality improvement of health services. The streamlined knowledge engineering process of quality evaluation and abstraction of critical information can generate helpful information for practitioners and researchers simultaneously.

Effect of testosterone replacement on the alteration of steroid metabolism in the hypothalamic-preoptic area of male hamsters treated with melatonin

Adult male hamsters were maintained under 14 hours of light per day and randomly assigned to groups that received daily afternoon melatonin (25 micrograms) or vehicle injections. Animals from both groups were killed following 4, 8, and 12 weeks of treatment. By 12 weeks, the melatonin-treated hamsters had significant reductions in the weights of the testes and seminal vesicles, serum testosterone levels, and activities did not differ between groups. In a second experiment, hamsters were hypothalamic-preoptic area (HPOA) aromatase activities. Hypothalamic-preoptic area 5 alpha-reductase activities did not differ between groups. In a second experiment, hamsters were again treated with melatonin or vehicle for 12 weeks prior to being killed. After 10 weeks of treatment, groups of melatonin-treated animals received subcutaneous silastic capsules (5, 10, or 20 mm) filled with testosterone. Animals in two other groups were given blank implants or no implants at all. Two weeks later, at autopsy, reproductive organ weights, serum testosterone levels, and HPOA aromatase activities were significantly suppressed by melatonin administration. 5 alpha-Reductase activity in the HPOA was not affected. Hamsters that had been given the 10- and 20-mm testosterone implants exhibited normal seminal vesicle weights and HPOA aromatase activities. These results suggest that melatonin-induced reduction of HPOA aromatase activity is mediated by decreased circulating levels of testosterone.

Suicide potential: evaluation by nonpsychiatrists

Since most people who commit suicide visit a physician in the week to year preceding the act, the physician is in a unique position to intervene before it is too late. If the patient has already made an attempt or gesture, the physician must evaluate the risk of suicide by inquiring into the patient's situation and state of mind and the circumstances of the act. The most common types of psychopathology in those who make a suicide attempt or gesture are depression and borderline personality. To detect suicidal patients who have not yet made an attempt or gesture, the physician must be alert to subtle cues, particularly somatic complaints.

Emergency psychiatric home visiting: report of four years experience

An Emergency Psychiatric Home Visiting Team made 624 visits to 443 patients in a 4 year period. In situations where patients were frequently psychotic, violent, or threatening violence, the team was sucessful at facilitating emergency care and defusing crisis situations. The team was equivocally successful at preventing hospitalization. Facilitation of hospitalization often became a more important function than prevention. Few visits were for suicidal behavior. No team member was ever harmed in the course of a visit. The team also served as a major psychiatric care provider and social support to a group of chronic patients and families who utilized the service multiple times.

A framework for the emergency evaluation of the suicidal patient

With increasing frequency, emergency room personnel face the anxiety of assessing suicide potential. The authors have developed and present here a mnemonic (SAD CHILDREN) which should facilitate the evaluation of potential in attempted or threatened suicide patients.

Emotional problems of the severely burned patient

In this article we have tried to present an overview of some of the common emotional responses and problems seen in severely burned patients. We have suggested that first consideration be given to learning what sort of person the patient is and becoming familiar with what the burned patient experiences. General preventive measures were suggested that included establishment of clear communication between patient and staff so that the patient has the best understanding possible of the nature of the injury and the treatment, allowing the patients as much control as possible in the treatment process, and providing adequate analgesic medication. We have described what may be observed when patients become anxious, fearful, angry, depressed, regressed, and psychotic, and have attempted to facilitate an understanding of what is occurring in patients showing these responses. Some common reactions of medical and nursing staff to the various emotional reactions were mentioned. In the final section we attempted to deal briefly with the responses of children and measures that can be taken with them. Most of the therapeutic measures suggested can be carried out by nonpsychiatric personnel if they are able to be empathetic and in touch with their own reactions to patients and to utilized common sense.

Reversal of bedrest-induced orthostatic intolerance by lower body negative pressure and saline

Six healthy male volunteers underwent two 1-week periods of bedrest, each preceded and followed by 2-week control and recovery periods. The daily metabolic diet contained 150 mEq of sodium. Following one 7-d bedrest period, each man was subjected to LBNP at a level of --30 mm Hg for 4 h while consuming 1000 ml of beef bouillon containing 154 mEq of sodium. After the other bedrest period, each man simply consumed the bouillon without LBNP treatment during 4 h of continued bedrest. Measurements of plasma volume and orthostatic tolerance were made before and after each treatment period. After combined LBNP and saline therapy, plasma volume and response to LBNP testing, as measured by heart rate and systolic BP, showed a return to pre-bedrest levels. Saline consumption alone had a lesser effect. With continuation of bedrest in three subjects, the beneficial effects of these measures appeared to be largely gone after 18 h.

Arsenic Tolerance in a Population of the Grass Andropogon scoparius Michx

Samples of Andropogon scoparius Michx. collected on an arsenic mine exhibited a wide range of tolerance to arsenic in solution, whereas plants of the same species growing in uncontaminated soil showed no tolerance. Arsenic tolerance must be an evolved character under genetic control. Furthermore, the degree of tolerance is related to the amount of arsenic in which the plant was growing.