The effects of selective cytokine inhibitory drugs (CC-10004 and CC-1088) on VEGF and IL-6 expression and apoptosis in myeloma and endothelial cell co-cultures

Myeloma cells and human umbilical vein endothelial cells (HUVECs) were co-cultured to model in vitro the interactions between myeloma and endothelium, and treated with thalidomide and two selective cytokine inhibitory drugs (SelCIDs, phosphodiesterase-4 inhibitors). Flow cytometry and enzyme-linked immunosorbent assay were used to assess production of two key cytokines--vascular endothelial growth factor (VEGF) and interleukin-6 (IL-6)--and apoptosis in co-cultured HUVECs and myeloma cells. VEGF was produced by both myeloma cells and HUVECs, while IL-6 was almost exclusively produced by endothelial cells. In co-culture, there was significant up-regulation of VEGF and IL-6 production compared with the sum of separate myeloma and endothelial cell cultures. SelCIDs markedly inhibited production of both cytokines in co-cultures, with CC-10004 being more potent than CC-1088. In addition, SelCIDs induced myeloma cell apoptosis. Apoptosis in co-cultured myeloma cells was significantly lower than in those cultured separately, suggesting that co-culture partially protected myeloma cells from drug-induced apoptosis. This protective effect was probably due to IL-6 produced by endothelial cells in co-culture as addition of anti-IL-6 neutralizing antibody, but not anti-VEGF antibody, abrogated it. In conclusion, SelCIDs can exert their anti-myeloma activity through two mechanisms, i.e. inhibition of VEGF and IL-6 production by interacting myeloma and endothelium and induction of myeloma cell apoptosis.     

A randomized placebo-controlled trial of combined early intravenous captopril and recombinant tissue-type plasminogen activator therapy in acute myocardial infarction.

The adjunctive use of intravenous captopril with tissue plasminogen activator early during acute myocardial infarction offers theoretic advantages of diminishing left ventricular volume, preventing ventricular dilation and improving patient survival. To test the safety and efficacy of combined early administration of intravenous captopril and recombinant tissue-type plasminogen activator (rt-PA), 38 patients treated with rt-PA 3 +/- 0.3 h (mean +/- SE) after the onset of myocardial infarction were randomized to intravenous followed by oral captopril or placebo therapy. They underwent cardiac catheterization with measurement of hemodynamic variables and left ventricular function and determination of serum renin, angiotensin and aldosterone levels on days 1 and 7. Oral administration of the selected agent was continued for 3 months along with other antianginal medications, including nonangiotensin-converting enzyme inhibitor vasodilators. Repeat measurements of left ventricular function were obtained before hospital discharge and at 3 months. There were no significant differences in baseline clinical characteristics between groups. One patient in the captopril-treated group became hypotensive during intravenous therapy, requiring discontinuation of treatment. Compared with the placebo-treated group, the captopril-treated group had significant reductions at day 7 in left ventricular end-diastolic pressure (22.5 +/- 1.5 versus 16.3 +/- 1.6 mm Hg, p less than 0.01) and mean systemic arterial pressure (93.6 +/- 3.3 versus 86.2 +/- 2.7 mm Hg, p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)     

Effects of sodium valproate and diazepam on beta-endorphin, beta-lipotropin and cortisol secretion induced by hypoglycemic stress in humans

Evidence that gamma-aminobutyric acid (GABA) and benzodiazepine receptors play a role in the inhibition of ACTH-cortisol secretion in humans has until now been drawn only from data indicating that sodium valproate, a GABA mimetic, and diazepam, a benzodiazepine, decrease hypothalamus-pituitary-adrenal (HPA) axis secretion in patients affected by pathological hypersecretion of the axis. Therefore, the present study investigated the effects, in the same healthy subjects, of sodium valproate or diazepam, on both basal and stress-stimulated concentrations of beta-endorphin (beta-EP), beta-lipotropin (beta-LPH) and cortisol. A single maximal dose of sodium valproate (400 mg) or diazepam (10 mg) did not significantly modify basal concentrations of beta-EP, beta-LPH and cortisol. On the other hand, in the same subjects, pretreatment with sodium valproate (20 mg X 3) or diazepam (10 mg X 2) blocked the increases in these hormones produced by hypoglycemic stress in all patients tested (p less than 0.01 vs. placebo at 45, 60 and 90 min after insulin injection), without affecting the decrease in blood glucose levels. The present data show that sodium valproate and diazepam inhibit stress-induced beta-EP, beta-LPH and cortisol secretion in humans, suggesting that endogenous GABA and benzodiazepine receptors participate in physiological mechanisms regulating the activity of the HPA axis.     

Epstein-Barr virus (EBV)-associated lymphoproliferations in severe combined immunodeficient mice transplanted with Hodgkin's disease lymph nodes: implications of EBV-positive bystander B lymphocytes rather than EBV-infected Reed-Sternberg cells

To establish an in vivo model for the study of Hodgkin's disease and Reed-Sternberg (RS) cells, 25 lymph node tissue samples involved by Hodgkin's disease were grafted into severe combined immunodeficiency (SCID) mice. Ten Epstein-Barr virus (EBV)-associated tumors were obtained in SCID mice. EBV-positive tumors growing in SCID mice were correlated with the presence of EBV-positive nonneoplastic B cells in patient tumors (90% v 26.6%; P<.01) and was independent of the EBV status of RS cells. Our results suggested that EBV-positive tumors growing in SCID mice originated from normal EBV-positive small lymphocytes (bystander B lymphocytes). We also compared the characteristics of these tumors with those obtained after transplantation of 15 non-Hodgkin's lymphoma and four reactive lymph nodes. The latent period to observe a growing tumor in SCID mice was similar between the two groups (12.86 +/- 5.59 weeks for Hodgkin's disease v 13.6 +/- 5.36 weeks for non-Hodgkin's lymphoma and reactive lymph nodes). The relatively high number of EBV-positive small lymphocytes detected in Hodgkin's disease and T-cell lymphoma compared with B-cell lymphoma may account for the greater percentage of EBV- positive tumors obtained in SCID mice. Our results show that SCID mice do not provide the growth conditions that are required for in vivo growth of RS cells. We noted in some SCID tumors, the presence of binucleated and/or multinucleated giant cells resembling RS cells. However, the presence of such cells was not restricted to mice grafted with lymph nodes involved by Hodgkin's disease. We postulate that in previous reports, cells resembling RS cells were just binucleated EBV- positive lymphoma blastoid cells rather than actual RS cells.     

Increased platelet aggregability associated with platelet GPIIIa PlA2 polymorphism: the Framingham Offspring Study

The platelet glycoprotein IIb/IIIa (GP IIb/IIIa) plays a pivotal role in platelet aggregation. Recent data suggest that the PlA2 polymorphism of GPIIIa may be associated with an increased risk for cardiovascular disease. However, it is unknown if there is any association between this polymorphism and platelet reactivity. We determined GP IIIa genotype and platelet reactivity phenotype data in 1422 subjects from the Framingham Offspring Study. Genotyping was performed using PCR-based restriction fragment length polymorphism analysis. Platelet aggregability was evaluated by the Born method. The threshold concentrations of epinephrine and ADP were determined. Allele frequencies of PlA1 and PlA2 were 0.84 and 0.16, respectively. The presence of 1 or 2 PlA2 alleles was associated with increased platelet aggregability as indicated by incrementally lower threshold concentrations for epinephrine and ADP. For epinephrine, the mean concentrations were 0.9 micromol/L (0.9 to 1.0) for homozygous PlA1, 0.7 mmol/L (0.7 to 0.9) for the heterozygous PlA1/PlA2, and 0.6 micromol/L (0.4 to 1.0) for homozygous PlA2 individuals, P=0.009. The increase in aggregability induced by epinephrine remained highly significant (P=0.007) after adjustment for covariates. For ADP-induced aggregation, the respective mean concentrations were 3.1 micromol/L (3.0 to 3.2), 3.0 micromol/L (2.9 to 3.2), and 2.8 micromol/L (2.4 to 3.3); P=0.19 after adjustment for covariates. Our findings indicate that molecular variants of the gene encoding GP IIIa play a role in platelet reactivity in vitro. Our observations are compatible with and provide an explanation for the reported association of the PlA2 allotype with increased risk for cardiovascular disease.     

Serum levels of sex hormone-binding globulin (SHBG) are not associated with lower levels of non-SHBG-bound testosterone in male newborns and healthy adult men

OBJECTIVE: It is generally accepted that SHBG decreases the bioavailability and activity of testosterone (T). In in vitro experiments increased levels of SHBG will be associated with decreased levels of non-SHBG bound testosterone (non-SHBG-T). However, in vivo SHBG can alter both production and clearance rates and thus plasma levels of T. DESIGN AND PATIENTS: In order to study the effect of SHBG on the levels of non-SHBG-T in vivo in the presence of an active hypothalamo-pituitary-gonadal (HPG) axis we conducted a cross sectional study in 400 healthy adult men with an age range of 40-80 years and in 106 newborn boys. MEASUREMENTS: In both groups, regression coefficients (beta) and partial correlation coefficients (r) were calculated for the relationship between SHBG and T or non-SHBG-T. Adult men were divided into age groups per decade (40-50 years, 51-60 years, 61-70 years and 71-80 years) to study possible differences in the impact of SHBG on the level of non-SHBG-T throughout ageing. RESULTS: Higher levels of SHBG were associated with higher levels of total testosterone in neonates (beta = 0.02 +/- 0.004, r = 0.44, P < 0.001) but not with non-SHBG-T (beta = -0.001 +/- 0.001, r = 0.05, P = 0.52). In adult men there was a significant age related increase in levels of SHBG and an age-related decrease of both total and non-SHBG-T. Higher SHBG was strongly associated with higher total testosterone in all age groups (beta = 0.26, 0.26, 0.26 and 0.23 for 40-50 years, 51-60 years, 61-70 years and 71-80 years, respectively, P < 0.001 for all age groups). Higher SHBG was not or only slightly associated with higher non-SHBG-T beta = 0.02 (P = 0.32), beta = 0.04 (P = 0.03), beta = 0.04 (P = 0.02) and beta = 0.02 (P = 0.16) for 40-50 years, 51-60 years, 61-70 years and 71-80 years, respectively. CONCLUSIONS: In contrast to general belief, SHBG levels barely influence levels of non-SHBG-bound testosterone both in male newborns and healthy adult men: the influence, if any, is positive. Consequently the age related increase of SHBG does not account for the age related decline in non-SHBG-T in healthy adult men.     

TMC114/ritonavir substitution for protease inhibitor(s) in a non-suppressive antiretroviral regimen: a 14-day proof-of-principle trial

OBJECTIVE: To evaluate antiviral activity, tolerability, and safety of the protease inhibitor (PI) TMC114 boosted with low-dose ritonavir (RTV). DESIGN: A randomized, open-label, controlled, phase IIA clinical trial in 15 sites in Europe with 50 HIV-1-infected patients who had taken multiple PIs. METHODS: At entry, PIs in non-suppressive regimens were replaced with TMC114/RTV (300/100 or 600/100 mg twice daily, or 900/100 mg once daily) or left unchanged for 14 days. The time-averaged difference (DAVG) in HIV-1 RNA from baseline, change in HIV-1 RNA from baseline, proportions achieving plasma HIV-1 RNA < 400 copies/ml and > or = 0.5 and > or = 1.0 log10 copies/ml reductions in HIV-1 RNA, and safety were assessed. RESULTS: DAVG responses in all TMC114/RTV groups (range, -0.56 to -0.81 log10 copies/ml) were significantly greater (P < 0.001) than in the controls (-0.03 log10 copies/ml). Median change at day 14 was -1.38 and +0.02 log10 copies/ml for all TMC114/RTV groups and the control group, respectively. A reduction of > or = 0.5 and > or = 1.0 log10 copies/ml was attained by 97% and 76% of patients, respectively, in all TMC114/RTV groups and by 25% and 17%, respectively, in the control group. HIV-1 RNA < 400 copies/ml at any time during treatment was achieved by 40% in the TMC114/RTV groups and 8% in the control group. Most common reported adverse events were gastrointestinal and central nervous system disorders (mild to moderate severity). No dose relationship was observed. Biochemical, haematological and electrocardiographic parameters showed no significant changes. CONCLUSIONS: TMC114/RTV demonstrated a potent antiretroviral effect over 14 days in multiple-PI-experienced patients and was generally well tolerated.     

Circadian variation and triggers of onset of acute cardiovascular disease

Information obtained during the past decade suggests the need to reexamine the possibility that the onset of myocardial infarction and sudden cardiac death is frequently triggered by daily activities. The importance of physical or mental stress in triggering onset of coronary thrombosis is supported by the findings that 1) the frequencies of onset of myocardial infarction, sudden cardiac death, and stroke show marked circadian variations with parallel increases in the period from 6:00 AM to noon, 2) transient myocardial ischemia shows a similar morning increase, and episodes are often preceded by mental or physical triggers, 3) a ruptured atherosclerotic plaque, often nonobstructive by itself, lies at the base of most coronary thrombi, 4) a number of physiologic processes that could lead to plaque rupture, a hypercoagulable state or coronary vasoconstriction, are accentuated in the morning, and 5) aspirin and beta-adrenergic blocking agents, which block certain of these processes, have been shown to prevent disease onset. The hypothesis is presented that occlusive coronary thrombosis occurs when 1) an atherosclerotic plaque becomes vulnerable to rupture, 2) mental or physical stress causes the plaque to rupture, and 3) increases in coagulability or vasoconstriction, triggered by daily activities, contribute to complete occlusion of the coronary artery lumen. Recognition of the circadian variation--and the possibility of frequent triggering--of onset of acute disease suggests the need for pharmacologic protection of patients during vulnerable periods, and provides clues to mechanism, the investigations of which may lead to improved methods of prevention.     

Functional hyposplenism in alcoholic liver disease: a toxic effect of alcohol?

Functional hyposplenism, seen in some patients with alcoholic liver disease, may contribute to the increased susceptibility to infections. As hyposplenism does not complicate non-alcohol related chronic liver disease, it is probably secondary to a toxic effect of alcohol. Over a two year period the case notes of 82 patients with alcoholic liver disease, whose splenic function had been assessed by the counting of pitted erythrocytes using differential interference microscopy, were reviewed to monitor mortality and the effects of hyposplenism. Thirteen patients (seven with hyposplenism) had serial measurements of pitted erythrocyte count made to assess the effect of abstinence from alcohol on splenic function. Thirty one of the 82 alcoholic patients had pitted erythrocyte counts greater than 2%. Eighteen of 82 (16%) patients died over the two years and 11 of these had been unable to stop drinking. Only one patient died of sepsis. Five patients (6%) had pitted erythrocyte counts comparable with those in splenectomised patients. In 12 of 13 patients who had abstained from alcohol for two months, the pitted erythrocyte count fell from a median of 3 to 1.3% (mean: 8.1 to 2.6%. p = 0.01). The pitted red cell count in two patients increased. One had abstained, the other had continued to drink heavily. Short term mortality in alcoholics is high, particularly if they continue to drink heavily. Only a few of these deaths are secondary to infection. Splenic function, as assessed by these methods, improves in most patients with abstinence, suggesting that the functional hyposplenism may be a result of a direct toxic effect of alcohol on the spleen.