Clinical evaluation of nitric oxide responses to anti-VEGF therapy with bevacizumab

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Background: Anti-vascular endothelial growth factor (anti-VEGF) therapy has been linked to hypertension (HTN) and arterial thrombo-embolic events that may involve changes in nitric oxide (NO) bioavailability. Methods: 25 patients (pts) with advanced cancer, normal renal function and blood pressure (BP), no increased risks for anti-VEGF toxicities, and not on medications known to confound biomarker studies (including anti-hypertensives) were treated with bevacizumab (BV) 15mg/kg d1, then 10mg/kg q2 week. Prior to biomarker assessment, all patients were placed on a calorie-, nitrate-, and salt-restricted diet for 72 hr. All measures were taken pre-treatment (preRx) and on day 28 of treatment (onRx). Dependant variables included; a) Brachial artery reactivity (BAR) following hyperemic flow stimulus (endothelium-dependent) and sub-lingual nitroglycerine (NTG; endothelium-independent); b) exhaled and plasma/urine total NO2/NO3 using chemiluminescence (Sievers 280NOA) with either KI or VCl3 in HCl as the reductants; c) blood pressure. Additionally, we measured multiple regulators of vascular tone and injury. Comparisons were analyzed using Spearman signed rank tests. Results: Of 25 pts (16 F, 9 M) treated, 21 patients were fully evaluable. Significant changes or strong trends were observed upon comparing preRx vs. onRx for BP (SBP +12.4, DBP +5.6, MAP +7.9 mm Hg), and flow-mediated BAR (-2.0%) with no changes in hyperemic flow/shear stimulus or smooth muscle function (BAR NTG), indicating a decrease in brachial artery endothelial responsiveness. Exhaled NO decreased (-0.8% d1vs d28 and -0.6% pre/post infusion day1). Measurement and data analysis of urinary/plasma NO2/NO3, as well as angiogenic markers, are almost complete and will be reported. Conclusions: After one month of treatment, BV increased BP and decreased endothelium- dependent BAR and exhaled NO, suggesting potentially broad, mechanism-based effects on NO bioavailability in patients.

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A phase I, open-label study of the safety and pharmacokinetics (PK) of pazopanib (P) and lapatinib (L) administered concurrently

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Background: P is a potent tyrosine kinase inhibitor of VEGF-R1, -R2, and R3, PDGF-α/β, and c-Kit. L is a potent inhibitor of ErbB1 and ErbB2 tyrosine kinases. Several lines of evidence support combined inhibition of VEGFR and Erb in the treatment of malignancies. Methods: Patients (pts) with solid tumors received P and L daily. Safety, limited PK, biomarkers, and clinical activity were evaluated. Dose escalation occurred in cohorts of 3–6 pts based on DLT. Results: Thirty-three pts received L/P doses of 750/250 (n=4), 750/500 (n=6), 1000/250 (n=3), 1000/400 (n=2), 1000/500 (n=4), 1250/250 (n=6), 1250/400 (n=5) and 1500/200 (n=3) mg once daily (qd). Preliminary mean plasma P concentrations 24 h after administration (C24) on Day 22 were ∼19 μg/mL and 23 μg/mL after administration of 250 mg and 500 mg, respectively. These values are similar to mean C24 values observed after administration of 800 mg P alone (23.1 μg/mL). Plasma L concentrations at 750 - 1500 mg qd were similar to those observed after monotherapy. The most frequent AE’s were diarrhea (Grade (G)1 n=10, G2 n=2, G3 n=3), fatigue (G1: n=7, G2 n=5, G4 n=1), nausea (G1 n=9, G2 n=2), anorexia (G1 n=8, G2 n=3), vomiting (G1 n=9), hair depigmentation (n=7), rash (G1 n=6, G2 n=1) and abdominal cramps (G1 n=3, G2 n=2, G3 n=1). Prolonged disease stabilization of > 16 wks (median 21.5 wks) occurred in 10 pts (RCC n=3, CRC n=3, GIST n=1, mesothelioma n=1, adenocarcinoma GE junction n=1, aggressive fibromatosis n=1). 3 pts (renal cancer n=2, and giant cell tumor of the bone n=1) demonstrated tumor shrinkage of < 30% (i.e. SD by RECIST). Conclusions: Concurrent administration of pazopanib and lapatinib was generally well tolerated. Coadministration of lapatinib may alter the PK of pazopanib.

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Upper urinary tract metastases from adenocarcinoma of the colon

An unusual presentation of colorectal metastasis to the upper urinary tract is reported. The metastasis manifested as a filling defect seen during antegrade pyelography. Cytologic evaluation of aspirated material demonstrated metastatic colonic adenocarcinoma. A dilated collecting system may be caused by intraluminal material including tumor and blood clots. Whenever fixed filling defects are encountered, urine cytology should be sent even in the absence of renal parenchymal involvement by tumor. The cytological evaluation may allow for prompt diagnosis and treatment.

Exploring distributive justice in health care

The allocation of resources to providers and the way in which the resources are then prioritised to specific service areas and patients remain the critical ethical decisions which determine the type of health system a community receives. Health care providers will never be given enough resources to satisfy all the demands placed upon them by a community that is becoming increasingly informed and demanding. This paper discusses the matter of justice as it relates to the distribution of health resources. It translates the theoretical constructs of distribution into a practical situation that arose at The Geelong Hospital. It is important to emphasise that the aim of giving the example is not necessarily to provide the right answer but rather to assist in determining what ought to be the questions.

The effects of collagen hydrolysat on symptoms of chronic fibromyalgia and temporomandibular joint pain

Twenty (20) people who had medically diagnosed fibromyalgia for two to 15+ years participated in and completed a 90-day evaluation to determine effects of collagen hydrolysat on symptoms of chronic fibromyalgia, with twelve reporting temporomandibular joint pain. Collagen hydrolysat is a food supplement that is available without prescription, with no known side effects. Participants were evaluated initially and then at 30-, 60-, and 90-day periods. Final results were obtained and comparisons made. The average pain complaint levels decreased significantly in an overall group average, and dramatically with some individuals. It was concluded that patients with fibromyalgia and concurrent temporomandibular joint problems may gain symptomatic improvement in their chronic symptoms by taking collagen hydrolysat.

Improving credibility of instructions in the balanced placebo design: a misattribution manipulation

Research using the balanced placebo design seeks to differentiate the physiological and psychological effects of drinking alcohol. Questions regarding the validity of the design center about experimenter instructions, particularly in the antiplacebo cell at higher blood alcohol content (BAC) levels. This study tested the plausibility of two misattribution strategies designed to reduce the conflict between experimenter instructions and internal cues of drunkenness. Forty-two participants (BAC = .055) were told that they received no alcohol, with internal cues of drunkenness said to be produced by a (sham) second drug, a (placebo) tachistoscopic display, or no misattribution given. The placebo drug group reported less alcohol intoxication without reporting less physical impairment than the control or tachistoscopic groups. Doubt of instructions was expressed more frequently in the control group than in the placebo drug group. Mean time to first reported doubt of experimenter instructions was longer for the placebo drug group. A manipulation check designed to account for demand effects indicated that instituting the pharmacologic misattribution increased the success of the manipulation over the control group. Providing a credible attribution for internal symptoms of drunkenness makes experimenter's instructions more credible, improving the validity of the antiplacebo cell of the balanced placebo design.

Increased complications in noninsulin-dependent diabetic patients treated with insulin versus oral hypoglycemic agents: a population study

A cross-sectional population study was performed in a cohort of 890 non-insulin-dependent diabetes mellitus (NIDDM) patients residing in the greater Denver metropolitan region. Its purpose was to evaluate the relationship between insulin and oral hypoglycemic agents (OHAs) with regard to metabolic control and diabetic complications. The mean glycosylated hemoglobin for patients treated with insulin was 12.0 +/- 0.15% versus 11.4 +/- 0.14% (p < .03) for OHA. The difference in fasting blood sugar for the insulin-treated group (195.0 +/- 3.5 mg/dl) versus the OHA-treated group (194.0 +/- 2.9 mg/dl) was not statistically significant. Categorical increases in urinary albumin excretion were associated positively within insulin versus OHA therapy (p < .0001). Patients treated with insulin therapy had a higher frequency of peripheral vascular disease (insulin therapy, 14%; OHA therapy, 10%; p < .05); neuropathy (insulin therapy, 55%; OHA therapy, 37%; p < .0001); and retinopathy (insulin therapy, 71%; OHA therapy, 45%; p < .0001). The frequency of cardiovascular disease was equivalent in the two groups (17% versus 13%). In protocols correcting for diabetes duration, glycosylated hemoglobin, and gender in a multivariate model, the use of insulin still was related significantly to increases in urinary albumin excretion (p < .01), retinopathy (p < .0001), and neuropathy (p < .0008). In a subgroup of individuals with diabetes duration > 10 years (n = 211 for insulin treatment, n = 118 for OHA treatment), the frequency of neuropathy still was significantly higher in the insulin group (63% vs 49%; p < .016) as was retinopathy (85% vs 58%; p < .0001). Overt albuminuria also was more significant in the insulin-treated patients (p < .04). In summary, the NIDDM patients treated with insulin had more nephropathy, retinopathy, and neuropathy than did NIDDM patients treated with OHA, independent of duration of diabetes, fasting blood glucose, glycosylated hemoglobin, age, and blood pressure level. These results in NIDDM patients may be due to contributions from worse blood glucose control at an earlier stage in the patients' diabetes and/or the mitogenic, atherogenic, thrombogenic, and vascular permeability effects of insulin.

Exercise and exhaustion effects on glycogen synthesis pathways

Female Sprague-Dawley rats were infused with [1-13C]glucose to measure the effect of endurance training and the effect of various metabolic conditions on pathways of hepatic glycogen synthesis. Four metabolic states [sedentary (S), trained (T), sedentary exhausted (SE), and trained exhausted (TE)] were studied. T and TE rats were trained on a motor-driven treadmill (30 m/min, 15% grade, 1.0 h/day, 5 days/wk) for 8-10 wk. After a 24-h fast, SE and TE rats were run to exhaustion (sedentary average = 78 min, trained average = 155 min) at a training pace and immediately infused with labeled glucose for 2 h. S and T rats were infused after a 24-h fast. After infusion, tissues were removed and glycogen was isolated and hydrolyzed to glucose. The glucose was measured for distribution of 13C by using nuclear magnetic resonance. Glycogen was synthesized predominantly by the indirect pathway for all metabolic states, indicating that infused glucose was first metabolized primarily in the peripheral tissue. The direct-pathway utilization was greater in rested S than in rested T animals (30 vs. 14%); however, for exhausted animals, the trained use of the direct pathway was greater (22 vs. 9%). Both TE and rested T animals utilize the indirect pathway a comparable amount. Sedentary animals, on the other hand, dramatically decreased utilization of the direct pathway, with exhaustive exercise changing from 30 to 9%. The results indicate that endurance training modifies glucose utilization during glycogen synthesis after fasting and exhaustive exercise.

Urinary albumin excretion as a predictor of diabetic retinopathy, neuropathy, and cardiovascular disease in NIDDM

OBJECTIVE

The relationship between urinary albumin excretion (UAE) and diabetic complications in NIDDM has not been studied in a large American population. The demonstrated relationship between increased UAE and the development of retinopathy, nephropathy, and neuropathy in IDDM makes this an important issue to also be studied in NIDDM patients.

RESEARCH DESIGN AND METHODS

A large population study of 947 NIDDM patients living predominantly in a metropolitan area was undertaken. Three categories of UAE, namely, normal albuminuria (< 20 micrograms/min), microalbuminuria (20-200 micrograms/min), and overt albuminuria (> 200 micrograms/min) were compared with 1) retinopathy as assessed by stereoscopic fundus photographs; 2) cardiovascular disease as assessed by a history of cardiac disease or stroke; ischemic changes on exercise treadmill testing; Q wave myocardial infarction; Estes, Sokolow, or Cornell criteria for left ventricular hypertrophy; positive Rose questionnaire for angina; and an abnormal Doppler exam for peripheral vascular disease; and 3) neuropathy as assessed by neurological symptom and disability scores, autonomic function testing, and quantitative sensory exams involving thermal and vibratory sensation. Selected patient characteristics were then evaluated to determine their effects on the presence of diabetic complications using univariate analyses. Multiple logistic regression analyses were then performed to determine the independent effect of UAE on these diabetic complications.

RESULTS

chi 2 analyses revealed that UAE was significantly associated with the presence of retinopathy (P < 0.001), neuropathy (P < 0.001), and cardiovascular disease (P < 0.001). In the multiple logistic regression analyses, UAE had strong independent associations with retinopathy, neuropathy, and cardiovascular disease.

CONCLUSIONS

Thus, increasing UAE in this large NIDDM population in the U.S. was associated with an increased prevalence of diabetic retinopathy, neuropathy, and cardiovascular disease. This suggests that UAE may be more than an indicator of renal disease in NIDDM patients and, in fact, may reflect a state of generalized vascular damage occurring throughout the body. Prospective studies in NIDDM patients are needed to determine the predictive effect of UAE and the effect of decreasing UAE on future diabetic micro- and macrovascular complications.

Baseline characteristics of participants in the Appropriate Blood Pressure Control in Diabetes trial

The ABCD (Appropriate Blood Pressure Control in Diabetes) trial is a large, prospective, randomized clinical trial designed to compare the effects of intensive with moderate blood pressure control on the prevention and progression of diabetic nephropathy, retinopathy, cardiovascular disease, and neuropathy in non-insulin-dependent diabetes (NIDDM). The secondary objective is to determine equivalency of the effects of a calcium channel blocker (nisoldipine) and of an angiotensin-converting enzyme inhibitor (enalapril) as a first-line antihypertensive agent in the prevention and/or progression of these diabetic vascular complications. The study consists of two study populations: a hypertensive one (diastolic blood pressure of > or = 90.0 mm Hg at the time of randomization) and a normotensive one (diastolic blood pressure of 80.0-89.0 mm Hg at the time of randomization). A total of 950 men and women aged 40-74 years were randomized and are being followed for 5 years at a single center. There were 470 randomized participants in the hypertensive population and 480 randomized participants in the normotensive population. This report summarizes the demographic, biochemical, and clinical characteristics of the randomized patients at the time of entry into the trial and evaluates the balance between the treatment groups within each population.

Effect of risk factors on exercise capacity in NIDDM

Exercise capacity has been used as a noninvasive parameter for predicting cardiovascular events. It is known that diabetic patients have an impaired exercise capacity when compared with nondiabetic age-matched control subjects, but the risk factors associated with this impairment have not been thoroughly analyzed. A total of 453 male and female NIDDM patients who underwent graded exercise testing with expired gas analysis were studied to determine the possible influences of demographic and cardiac risk factors on exercise capacity. Univariate and multiple linear regression analyses were performed on baseline patient characteristics with respect to peak oxygen consumption (VO2). In the regression analyses, African-American race was strongly associated with a decrease in peak VO2; the difference in means between African-Americans and other subjects for men was -2.50 ml.kg-1.min-1 (-4.28, -0.07, 95% CI) (P < 0.006) and for women was -2.96 ml.kg-1.min-1 (-4.45, -1.47) (P < 0.0002). Univariate analyses revealed that African-American subjects had increased prevalence, longer duration, and higher systolic and diastolic hypertension than the non-Hispanic and Hispanic whites. Other independent predictors of peak VO2 (reported as change in peak VO2 in milliliters per kilogram per minute) were BMI (men: -0.39 kg/m2 [-0.52, -0.29], P < 0.0001; women: -0.39 kg/m2 [-0.48, -0.31], P < 0.0001), age (men: -0.16/year [-0.23, -0.09], P < 0.0001; women: -0.17/year [-0.24, -0.11], P < 0.0001), baseline resting systolic blood pressure (men: -0.03/mmHg [-0.06, -0.01], P < 0.05; women: -0.03/mmHg (-0.06, -0.01)f1p4< 0.05), and pack-years smoking (men: -0.04/pack-years [-0.04, -0.01], P < 0.01; women: -0.04/pack-years [-0.07, -0.01], P < 0.0001). Thus, in this large NIDDM study, weight loss, smoking cessation, and aggressive blood pressure control, particularly in African-Americans with NIDDM, would appear to be important in improving exercise capacity and potentially improving the increased cardiovascular mortality associated with an impaired exercise capacity.

Clinical factors associated with urinary albumin excretion in type II diabetes

Clinical factors associated with urinary albumin excretion (UAE) in type II diabetes are less well known than in type I diabetes. To examine the factors associated with UAE in type II diabetes, 933 Appropriate Blood Pressure Control in Diabetes Trial patients were classified according to UAE status: normoalbuminuria (< 20 micrograms/min), microalbuminuria (20 to 200 micrograms/min), and macroalbuminuria (> 200 micrograms/min). The class of UAE was then correlated with various clinical factors. Using univariate analyses, Hispanic ethnicity, African-American race, male gender, poor glycemic control, insulin use, long duration of diabetes, dyslipidemia, diastolic and systolic hypertension, smoking, and obesity were significantly correlated with microalbuminuria and macroalbuminuria. Using multivariate logistic regression analyses controlling for diabetes duration, glycosylated hemoglobin, gender, and race, the most significant predictors of microalbuminuria and macroalbuminuria were systolic hypertension, body mass index, high-density lipoprotein cholesterol, insulin use, and smoking pack-years. Of these factors, several are potentially reversible with aggressive intervention.

Determination of the glycogen synthesis pathway by 13C nuclear magnetic resonance analysis

The level of hepatic glycogen synthesized directly from glucose was measured in rats with [1-13C]glucose. The nuclear magnetic resonance (NMR) spectrum of glucose was used to measure the distribution of the 13C label from C1 to the other carbons. Female Sprague-Dawley rats were surgically implanted with catheters in the left carotid artery and the right jugular vein, followed by a 3-day recovery period and a 24-hour fast to deplete liver glycogen. A 2-hour infusion of the fasted animal with [1-13C]glucose was immediately followed by the removal of blood and liver tissue. The liver was divided into the right, left, caudate, and medial lobes, and then freeze-clamped in liquid nitrogen and stored at -80 degrees C. The 13C NMR glucose spectra were obtained from glycogen that was isolated from each liver lobe and hydrolyzed to glucose with amyloglucosidase. Spectra were obtained at 50.3 MHz in a narrow-bore Gemini 200-MHz NMR spectrometer (Varian, Palo Alto, CA). The distribution of 13C onto glucose carbons was measured from these spectra, and the percent direct pathway was calculated to be 29% +/- 2.5%. Metabolic variation for the synthesis of glycogen within the liver was determined by measuring the direct pathway contribution in each of the four liver lobes. Percent direct pathway values were similar (P > .05) in right (35% +/- 4.9%), left (26% +/- 5.1%), medial (25% +/- 4.9%), and caudate (27% +/- 5.6%) lobes. For some of the animals, the direct pathway was determined by infusion with [6-13C]glucose.(ABSTRACT TRUNCATED AT 250 WORDS)

The ABCD (Appropriate Blood Pressure Control in Diabetes) trial. Rationale and design of a trial of hypertension control (moderate or intensive) in type II diabetes

OBJECTIVE

The primary objective of the ABCD (Appropriate Blood Pressure Control in Diabetes) Trial is to determine the efficacy of intensive versus moderate antihypertensive control on the outcome of type II diabetic end-organ complications in normotensive and hypertensive populations. The secondary objective is to determine whether any differential effect on end-organ complications exists between an angiotensin converting enzyme inhibitor (enalapril) and a calcium channel blocker (nisoldipine).

DESIGN

The ABCD Trial is a prospective, controlled, randomized, double-blind trial, with a planned follow-up of 5 years.

SETTING

All patients are seen at the Colorado Prevention Center, site of the ABCD Trial, for follow-up visits.

PATIENTS

Patients are type II diabetic males and females between the ages of 40 and 74 years with entry diastolic blood pressures > or = 80 mmHg. Patients were recruited from University of Colorado-affiliated hospitals, several health maintenance organizations, and mailing lists from the Colorado affiliate of the American Diabetes Association.

INTERVENTIONS

Patients were randomized to intensive antihypertensive drug therapy or moderate antihypertensive drug therapy. Patients were also randomized to nisoldipine or enalapril, with open-label medications added if further blood pressure control was necessary.

MAIN OUTCOME MEASURES

The primary outcome measure is glomerular filtration rate as assessed by 24-hour creatinine clearance. Secondary outcome measures are microalbumin urinary excretion, left ventricular hypertrophy, retinopathy, and neuropathy. Cardiovascular morbidity and mortality will also be evaluated.

CONCLUSION

Given the data showing the impact of hypertension on diabetic complications, the ABCD Trial was designed to determine if intensive antihypertensive therapy will be more efficacious than moderate antihypertensive therapy on the outcome of these complications. Results from the ABCD Trial are expected to lend interpretable and clinically relevant findings with regards to the treatment of hypertension in type II diabetes.

Discovering work excitement among navy nurses

An interest in what makes work exciting among Navy Nurse Corps officers led to the use of Simms' work excitement data collection protocol in Navy Medical Centers. Significant levels of work excitement were found among Navy nurses when compared to civilian nurses in non-military settings. Overall, results indicated that Navy nurses are excited about the variety, the leadership/management experiences, and the opportunities for teaching and learning--elements that are the very essence of Navy nursing practice.