A phase II study of ABT-510 for the treatment of metastatic melanoma

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Background: ABT-510 is a synthetic peptide analog of thrombospondin-1 demonstrating inhibition of VEGF/bFGF mediated human endothelial cell migration, proliferation, tube formation, cornea-neovascularization as well as inhibition of tumor growth in vivo (B16F10 melanoma). Having been found to be safe in phase I testing, ABT-510 has entered phase II trials. Presented are the results of a phase II study using ABT-510 for the treatment of stage IV melanoma. Methods: A two stage phase II clinical trial was conducted to assess the anti-tumor activity, safety profile and pharmacodynamics of ABT510 in patients with stage IV melanoma. Patients self-administered 100mg of ABT-510 subcutaneously twice/day. Therapy was continued in the absence of excessive toxicity or tumor progression. Primary endpoint was 18 week progression free survival rate. Enrolled were patients at least 18 years of age with measurable (RECIST) metastatic melanoma, ECOG performance status of 0–2 and normal pre-registration blood tests. Exclusion criteria included: cancer therapy less than 4 weeks prior to registration; failure to recover from prior therapy; brain metastases; significant recent bleeding; uncontrolled hypertension; and ongoing anti-coagulation. Pregnant or nursing women were not eligible. Results: Twenty-one patients (67% male) were enrolled with a median age of 55 years. Most patients had M1c disease (80%) and 62% had prior chemotherapy for stage IV melanoma. None of the patients were ineligible/canceled participation. After the first stage of the trial was complete, only 3 of the first 20 patients enrolled were progression-free at 18 weeks. Having not met the minimal clinical efficacy requirement (at least 7 of the first 20 patients progression-free at 18 weeks) the trial was closed to further accrual. Correlative laboratory studies suggested decreases in some of the measured parameters of angiogenesis (VEGFC, circulating endothelial cells) with no impact on immune homeostasis. Conclusions: Single agent ABT-510 therapy administered at 100mg twice/day to patients with previously treated metastatic melanoma did not demonstrate significant clinical efficacy. However, changes in measured parameters of angiogenesis suggest possible clinical efficacy with higher dosing or in combination with cytotoxic therapy.

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Validation of liquid chromatographic method for analysis of lidocaine hydrochloride, dexamethasone acetate, calcium dobesilate, buthylhydroxyanisol and degradation product hydroquinone in suppositories and ointment

In this paper, there was developed a sensitive, precise and accurate reversed-phase liquid chromatographic (RP-HPLC) method and validated for simultaneous determination of lidocaine hydrochloride, dexamethasone acetate (DA) and calcium dobesilate (CD) in suppositories and ointment. Also there was achieved a parallel analysis of buthylhydroxyanisol, as a preservative, and hydroquinone, as a degradation product of calcium dobesilate, present in these dosage forms. The relative standard deviation (RSD) values for all five compounds indicated a good precision and accuracy of the RP-HPLC method. Method is selective, sensitive and reproducible with good recovery values and can be applied in simultaneous determination of all mentioned compounds.

Acute Fatty Liver of Pregnancy - An Underlying Condition for Herpes Simplex Type 2 Fulminant Hepatitis Necessitating Liver Transplantation

The infrequent occurrence of herpes simplex virus (HSV) hepatitis in healthy women in comparison with the high prevalence of HSV infections suggests that, in addition to deranged immunity, an underlying condition in the liver might be necessary to develop HSV hepatitis. We report the case of a 28-year-old pregnant woman in the 28 (th) week of gestation. Following HSV type 2 infection of the uterine cervix, acute liver failure developed, necessitating urgent liver transplantation. In addition to fulminant HSV type 2 hepatitis, the explanted liver also showed the histological features of acute fatty liver of pregnancy. The presented case suggests a possible pathogenetic role of acute fatty liver of pregnancy in the development of fulminant HSV hepatitis following recurrent infection with HSV in healthy pregnant women. We believe that early histopathological diagnosis, followed by specific antiviral treatment and liver transplantation in selected patients may improve the clinical outcome of otherwise almost uniformly fatal HSV hepatitis.

Development and validation of RP–HPLC method for cetrimonium bromide and lidocaine determination

The simple and rapid RP-HPLC method, for the simultaneous determination of lidocaine and cetrimonium bromide in the presence of pellet color corrigent, was developed. Separations were performed on a Beckman Ultrasphere ODS 4.6 mm x 15 cm, 5 microm particle column at 40 degrees C. The mobile phase consisted of water phase and acetonitrile (72:28 V/V), pH value of the mobile phase was adjusted to 2.0 with 85% ortophosphoric acid. Bisacodil was used as an internal standard. The flow rate was 1 ml/min and UV detection was performed at 208 nm. The proposed RP-HPLC method was validated and all the parameters for the validation of the method are given. According to the obtained results, the developed method was found to be suitable and accurate for the determination of these drugs in commercial formulations.

Strenuous exercise and action of antioxidant enzymes

BACKGROUND

During the course of evolution, the antioxidant system has developed in order to prevent cell damage and to maintain equilibrium between production of free radicals and their neutralization. Because of increased oxygen consumption and energy utilization during physical work, oxidative stress may be expected. A review of current literature revealed no consistent data regarding activity of antioxidant enzymes during strenuous exercise.

OBJECTIVES

The aim of this paper was to identify the activity of antioxidant enzymes in erythrocytes during strenuous short-term exercise.

METHODS

The activity of superoxide dismutase (SOD), glutathione peroxidase (GPX), and glutathione reductase (GR) were investigated. Also, glucose-6-phosphate dehydrogenase (G-6-PDH) activity was studied in order to assess the level of recovery of reduced glutathione (GSH) by maintaining NADPH. Peripheral blood was drawn before (1) and immediately after (2) the test completed. Modified Astrand's protocol on a bicycle ergometer was used to achieve strenuous exercise in volunteers.

RESULTS

The results obtained were: SOD1--897.95 +/- 99.85 U/g Hb and SOD2--828.38 +/- 75.12 U/g Hb; GPX1--30.19 +/- 4.03 U/g Hb and GPX2--26.00 +/- 4.85 U/g Hb; GR1--58.29 +/- 8.23 U/L and GR2--62.67 +/- 7.29 U/L; G-6-PDH1--14.97 +/- 3.79 IU/g Hb and G-6-PDH2--16.5 +/- 2.74 IU/g Hb. The difference was statistically highly significant: p < 0.001 for SOD, GPX, and GR activities, and p = 0.018 for G-6-PDH activity.

CONCLUSION

The results reflect the presence of oxidative stress in erythrocytes after strenuous exercise. Further investigations should clarify the role of other antioxidant-relevant compounds during exercise such vitamins, trace elements, and metals and enable estimation of the level of damage caused by generation of free radicals (e.g., malonyl dialdehyde, 8-hydroxydeoxyguanosine etc.). All this information together will undoubtedly give us clear insight into free radical generation during strenuous workloads.

[Diagnostic validity of radionuclide phlebography in the detection of clinically occult deep venous thrombosis in patients with thromboembolism]

Diagnostic reliability of radionuclide phlebography (RNP) compared to contrast phlebography in the detection of deep veins' thrombosis (DVT) in patients with confirmed thromboembolism of the lungs (TEL) was evaluated. RNP. These findings were compared to contrast phlebography (CP), performed in the group of 25 patients in whom TEL was confirmed clinically, radiologically, scintigraphically and biochemically, but without clinical signs and symptoms of DVT. In 15 patients where RNP revealed unilateral DVT, CP finding was confirmed in all: in 6 (40%) on the left, and in 9 (60%) on the right side. In 10 patients with bilateral signs of DVT observed by scintigraphy, DVT finding was confirmed in 7 (70%), while in 3 (30%) patients, scintigraphic signs of DVT were falsely positive. In the segments of deep venous system, specificity of RNP in the detection of DVT in the lower leg was 60%, sensitivity was 100%, accuracy was 64% with 62% falsely positive findings. In the upper legs specificity was 79%, sensitivity was 100%, and accuracy was 86% with 24% falsely positive findings, while in the pelvis specificity was 87%, sensitivity was 100%, accuracy was 83% with 14% falsely positive findings.

In vitro effects of mycophenolic acid on the nucleotide pool and on the expression of adhesion molecules of human umbilical vein endothelial cells

The immunosuppressive drug mycophenolate mofetil (MMF) and its active metabolite mycophenolic acid (MPA) selectively inhibit inosine 5'-monophosphate dehydrogenase (IMPDH), and therefore interfere with cellular guanine nucleotide biosynthesis. IMPDH is additionally involved in the synthesis of membrane glycoproteins, some of which are adhesion receptors known to play an active part in the regulation of cell-cell contacts, which are crucial in the process of recruitment and transendothelial infiltration of activated leucocytes in the transplanted organ. As a consequence, MPA leads to a reduction of cellular infiltrates in the course of transplant rejection. In the present study, the effects of MPA on human umbilical vein endothelial cells (HUVEC) are investigated at both molecular and cellular levels. In our experiments, HUVECs are treated with tumor necrosis factor-alpha (TNF-alpha; 10 ng/ml) in order to mimic activation occurring at a rejection crisis. The dose-dependent influence of concomitant incubation with MPA (5-20 micromol/l; 48 h, 37 degrees C, 5% CO2) on their intracellular nucleotide profile is observed by determining the concentrations of purine and pyrimidine nucleotides, using a HPLC method based on solvent generated ion-exchange. The possibility of synergistic effects is investigated by incubating endothelial cells with mixtures of three different immunosuppressants (mycophenolic acid; cyclosporin A, 100 ng/ml; prednisolone, 1 micromol/l)--a combination commonly used after transplantation--varying the amount of MPA (5-20 micromol/l). Stimulation with TNFalpha does not significantly modulate the intracellular levels of nucleotides quantitated. In the presence of MPA concentrations of at least 5 micromol/l, GTP levels (68+/-12%) are significantly decreased compared to controls (100%). At a concentration of 20 micromol/l MPA, the GTP amount is reduced to 58+/-7%. In contrast to these observations, the levels of UDP and UTP are increasing significantly under coincubation with MPA concentrations greater than 5 micromol/l. At 20 micromol/l MPA, UDP and UTP are increased to 147+/-19% and 114+/-11%, respectively. All other nucleotides (CTP, ADP, ATP) reveal no significant alterations in their intracellular concentrations under the conditions applied. Incubation of TNFalpha-treated HUVEC monolayers, with a mixture of three immunosuppressive drugs varying the amount of MPA, show no significant differences compared with the data observed after incubation with MPA alone. In addition, the influence of MPA (10 micromol/l) on a cellular level is observed by measuring the cell surface expression of adhesion molecules on cytokine-stimulated HUVECs, using TNFalpha (10 ng/ml), interferon-gamma (100 ng/ml), interleukin-1beta (10 ng/ml) and interleukin-8 (20 ng/ml). Expression of the intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), endothelial leucocyte adhesion molecule-1 (ELAM-1) and platelet endothelial cell adhesion molecule-1 (PECAM-1) was assessed by flow cytometry. Activation of endothelial cell monolayers with TNFalpha significantly increases the mean fluorescence intensity of VCAM-1 (361+/-14%) and ICAM-1 (429+/-47%) surface expression, compared to controls, and additionally induces E-selectin expression (2919+/-134%). The same tendencies, but in a lesser degree, are observed under stimulation of cells with either IFNgamma or IL-1beta. Incubation with a combination of TNFalpha and MPA leads to a significant reduction in VCAM-1 (329+/-13%) and E-selectin (2613+/-167%) expression, compared to the values obtained for HUVEC incubated with the cytokine alone. Treatment of the cells with IL-1beta/MPA also reduces the expression of VCAM-1 to a level significantly lower than the level observed after stimulation with IL-1beta. Incubation with MPA alone reveals no significant modulation in the expression of all surface molecules tested compared to the values of unstimulated HUVECs. The experiments show that the immunosuppressive action of MPA not only inhibits lymphocyte proliferation but also decreases the expression of adhesion molecules on endothelial cells, which are the first target of the cellular rejection process.

[Stress-rest myocardial tomoscintigraphy with 99mTc-tetrofosmin in the diagnosis of ischemic disease]

The aim of this study was to evaluate the accuracy of 1-day stress-rest technetium-99m tetrofosmin myocardial tomography in the identification of patients with coronary artery disease (CAD), and in the detection of the individual occluded coronary vessels. A total of 42 patients with suspected CAD were studied. Significant coronary narrowing (> or = 50% luminal stenosis) was detected by angiography in 22 patients. All patients received two i.v. injections of 99mTc tetrofosmin, one at peak exercises (370 MBq) and the other (740 MBq) at rest 3 h after exercise (images 15-30 min after injections for both studies). At visual analysis, all patients with CAD (> or = 50% luminal stenosis) (n-22) had an abnormal 99mTc tetrofosmin tomogram. Nine out of 20 patients without significant coronary narrowing (but with tortuosis, atheromathosis, with microvascular diseases) showed abnormal findings. Overall sensitivity, specificity and diagnostic accuracy in the identification of CAD was 100%, 55%, and 79%, respectively. Sensitivity, specificity and diagnostic accuracy in the identification of individuals with occluded coronary vessels were 100%, 76% and 85%, respectively. The results of this study demonstrate that 1-day exercise-rest 99mTc tetrofosmin single-photon emission tomographic imaging (SPET) is a suitable and accurate technique to identify patients with CAD and for detection of individual occluded coronary vessels.

The importance of antioxidant enzyme and total antioxidant status of patients with acute myocardial infarction on thrombolytic therapy

It is believed that intensive production of free radicals occurs immediately after reperfusion, and that it explains a series of adverse effects of reperfusion. The aim of the study was to establish the importance of the antioxidative enzymes superoxide dismutase (SOD), glutathione peroxidase (GPX) and the total antioxidant status (TAS) in patients with acute myocardial infarction according to success or failure of reperfusion. Enzyme activities in erythrocyte hemolysate and concentration of TAS in plasma were determined by Randox kits in 50 patients with acute myocardial infarction. No significant differences in TAS between the mean values against either clinical status or the 10 time intervals were recorded. The SOD and GPX values were significantly influenced by the presence or absence of reperfusion (p<0.05). Monitoring of SOD and GPX at ten time points: before administration of streptokinase, 1, 3, 6, 12, 18, 24 hours, 2, 3 and 5 days after administration of streptokinase revealed the lowest SOD levels up to one hour before administration of streptokinase, supporting the fact that the maximum production of free radicals is achieved at that time. GPX values differed for 24 hours according to whether reperfusion was achieved or not. The obtained results suggest that free radical production is increased after reperfusion, and monitoring of antioxidant enzymes may help to evaluate the success of thrombolytic therapy.

Second-derivative spectrophotometric assay of pseudoephedrine, ibuprofen and loratadine in pharmaceuticals

In this paper the second-derivative spectrophotometric method for the simultaneous determination of pseudoephedrine (CAS 90-82-4) in the combinations with ibuprofen (CAS 15687-27-1) and loratadine (CAS 79794-75-5) is described. Optimal conditions for the quantitative analysis of coated tablets (Test I) and tablets (Test II) were settled. The second-derivative order of the spectra in ethanol with the wavelength modulation was used. For the quantitative assay for all of the investigated substances in the laboratory mixture or in respective pharmaceutical dosage forms the "zero-crossing" technique was applied. The authors propose this second-derivative spectrophotometry for a rapid, simple, precise and accurate determination of the mentioned tests or a corresponding multicomponent mixture.

Neuroendocrine responses following graded traumatic brain injury in male adults

In an effort to characterize thyroid, gonadal and adrenal function following neurotrauma, the present study determined serum concentrations of thyroid-stimulating hormone (TSH), total triiodothyronine (T3), thyroxine (T4), testosterone and cortisol over a 7 day period in 31 patients with traumatic brain injury. The study group consisted of eight patients with mild closed head injury (Glasgow Coma Scale--GCS 13-15), 10 patients with extensive penetrating head injury (GCS 4-6) and 13 patients with blast injuries but without direct head trauma. The latter group was included in the study because the development of indirect brain trauma has previously been implicated in blast injuries. Patients with multiple injuries were not included. Following mild injury (GCS 13-15), TSH was increased up until day 3 after injury. T3 levels were elevated on days 1, 5 and 7 after injury while T4 remained unchanged throughout. While testosterone was decreased over only the first 2 days post-trauma, cortisol was increased over these first 2 days after injury. In contrast, following severe penetrating injury (GCS 4-6), there were significant declines in TSH, T3 and testosterone over the 7 day observation period post-trauma. Serum cortisol also declined in these patients between 1-3 days after injury, before increasing again on days 5 and 7 after injury. Following indirect neurotrauma, TSH was slightly decreased immediately after trauma but increased to above normal levels on days 5 and 7 post-trauma. Similarly, T3 initially declined after injury, but then increased to above normal levels between 5 and 7 days after injury. T4 and testosterone remained unchanged over the entire post-traumatic period. Serum cortisol was significantly increased after indirect neurotrauma but only up to day 2 post-trauma. In summary, patients with both direct and indirect traumatic brain injury demonstrated endocrine alterations after trauma, the dynamics of which may be a reflection of the severity of brain damage.

Reactivation of hepatitis B but not hepatitis C in patients with malignant lymphoma and immunosuppressive therapy. A prospective study in 305 patients

BACKGROUNDS/AIMS

The aim of this prospective study was to determine the prevalence of hepatitis B (HBV) and hepatitis C viral (HCV) infection as well as to study the morbidity and mortality of viral reactivations in patients treated with corticosteroid containing chemotherapy.

METHODOLOGY

From January 1991 to April 1996, 305 patients admitted for treatment of Hodgkin's disease and non-Hodgkin's lymphoma were tested for HBV, and 181 patients for HCV infection. They were followed-up regularly on a monthly basis with liver biochemistry and viral serology.

RESULTS

The prevalence of HBs antigen and hepatitis C antibody was found to be 3.2% and 16% respectively. There were 9 reactivations of HBV among 8 HBs antigen positive patients (78%), one among 35 HBs antigen negative patients (2.8%) and none in HCV positive patients. In 83% of cases, reactivation was connected to chemotherapy and corticosteroids. The overall death rate of HBV reactivation was 37%; in severe hepatitis it was 60%. All fatal reactivations were in anti-HBe positive patients.

CONCLUSIONS

The low prevalence of HCV failed to demonstrate an association between hepatitis C viral infection and lymphoma in Slovenia. Reactivation of HBV infection in HBsAg positive malignant lymphoma patients is a common and often fatal complication of treatment.

Treatment options in Western hepatocellular carcinoma: a prospective study of 224 patients

BACKGROUND/AIMS

Though hepatocellular carcinoma (HCC) is one of the most frequent malignant tumors in the world, the optimal therapeutic strategy is still poorly defined. This is mainly due to geographic differences in HCC which may affect the validity of treatment regimens in differents areas of the world. The aim of the present study was to analyze the natural course of the disease as well as to assess the efficacy of different therapeutical schemes in HCC observed in Ljubljana (Slovenia) and Trieste (Italy), two cities in Western Europe situated close to each other.

METHODS

During the period from January 1988 to December 1993, 224 consecutive patients (132 in Trieste and 92 in Ljubljana) with HCC were enrolled in the study. Patients were treated with the following 3 schemes: surgery 39 (17.4%), transcatheter chemoembolization (TACE) 116 (51.8%), and no treatment 69 (30.8%). The tumor was classified by Okuda staging and the liver disease by Child-Pugh score. Patients were followed up for 12-60 months, with an average of 40 months. The response rate to TACE and recurrence following surgery were evaluated. Comparative analysis of survival between different treatment groups was performed.

RESULTS

The natural course of the disease, and other characteristics of the HCC, showed a typical Western type of tumor. Liver disease was scored as Child A in 58%, Child B in 30% and Child C in 12%, and the tumor was staged as Okuda I in 52%, Okuda II in 37% and Okuda III in 11%, respectively. Treatment with TACE was followed by an objective response in 27%, with a median survival of 31 months. Surgery was followed by a recurrence rate of 77% within 19.5 months and median survival of 49 months. The overall median survival of nontreated patients was 8 months. Survival in each group of patients differed significantly between all three consecutive stages of Okuda (p<0.001). In contrast, the differences in survival were significant only between Child A and B (p<0.02). The differences between Child B and C were not significant.

CONCLUSIONS

This study emphasizes the importance of staging in the choice of treatment modality and diffusion of HCC in affecting an overall response to treatment and survival. Surgery is highly effective in monofocal HCC of Okuda I and II without cirrhosis. TACE is effective in Okuda I and II and Child A cirrhosis only. The treatment of HCC in Child B cirrhosis needs further studies. In Child C and/or Okuda stage III of HCC, any treatment except pure symptomatic relief is detrimental and should not be used.

Markers of oxidative stress after renal transplantation

An increased degree of oxidative stress (OS) in chronic renal failure (CRF) and a possible role of free radicals in CRF have already been described. However, data on OS after renal transplantation are scarce. The aim of the present study was to estimate the degree of OS in renal transplant patients. The study included four groups: 1) 15 haemodialysis patients (HD group), 2) 11 renal transplant patients with stable function (SF group), 3) 12 renal transplant patients with chronic biopsy-proven rejection (CR group), and 4) 10 healthy controls (C group). Markers of OS (malondialdehyde and thiol group levels) and antioxidant activity (glutathione peroxidase and Cu,Zn-superoxide dismutase) were determined in plasma and in red blood cells of all examined individuals. After successful renal transplantation a significant improvement, but not normalization, of antioxidant enzyme activities accompanied by significantly reduced lipid peroxidation were found. In the CR group the degree of OS was increased, and our results suggest that OS may be a relevant pathophysiological factor for CR development.

Goodness of Dot Patterns and Completion Variability: Effects of Equidistance and Collinearity of Dots

Visual patterns that are initially poorly specified can be perceptually completed into different Gestalten (eg dot patterns can impose the perception of different figures). In the present study the following hypothesis is evaluated. If the goodness of initial patterns is high enough (high Prägnanz), then the completion of initial patterns will result in a single Gestalt (high stability of percept). On the other hand, if the goodness is low (low Prägnanz), the completion will result in several Gestalten (perceptual multistability). In experiment 1 subjects estimated the goodness of four sets of initial 8-dot patterns. The distance between the dots was systematically varied. In experiment 2 the variability of completion of the same initial stimuli was examined. Subjects were asked to choose from a given set of figures the one that was most strongly suggested by the exposed initial dot pattern. The entropy, as a measure of the completion variability, was derived from the proportions of the choices of figures. The correlation between goodness estimates (Prägnanz level) and entropy (completion multistability) was significant: the higher the goodness, the lower the multistability of initial pattern completion. The arrangement of dots was an important stimulus constraint of the dependent variables. Increasing the number of equidistant extents between dots increased multistability and decreased goodness. Collinearity of dots induced a decrease of multistability and an increase of goodness.

Spontaneous regression of hepatocellular carcinoma

Spontaneous regression of a histologically proven hepatocellular carcinoma was observed in a 62-yr-old male Slovenian patient with HBsAg-positive liver cirrhosis and a remarkable family history of hepatocellular carcinoma. After 3 months of persistent high fever, the patient's condition improved, and liver resection was performed. Histological examination of resected liver specimen revealed necrosis with pseudocapsular lining and no malignant cells. The patient is alive, without evidence of recurrence, 8 yr after the diagnosis was established.

A new assay for intracellular measurement of inosine monophosphate dehydrogenase activity: a guide for better selection of patients for enzyme-targeted chemotherapy

We developed a new cytochemical assay for identification of cells containing inosine monophosphate dehydrogenase (IMPDH) and measurement of tumor cell sensitivity to the escalating dose/schedule of the IMPDH pattern-targeting drugs. The assay is based on cytochemical principles for development of DH activity markers inside morphologically classified cells, image analysis for measuring the amount of this marker, and computer assistance for data management. The assay was optimized on a human leukemia cell line (K562-NS) and reference values for enzyme activity were established. Assay specificity was determined with different substrates and enzyme inhibitors. Sensitivity depends on the measuring instrument (image analyzing system), and the precision of the biological model used for assessment of reference values was high. IMPDH-positive malignant cells were found in all specimens obtained from acute leukemia and solid tumor patients (13/13 and 29/29) and in four human tumor cell lines (K562, K562-NS, HL60, and HL60-M). Cells of the K562-NS line were exposed to tiazofurin and ribavirin in conventional assays for assessment of drug-induced acute and subacute toxicity/sensitivity. A reduction of IMPDH activity was recorded at drug concentrations below the range at which cell damage appeared.