Measurement of mitogen stimulation of lymphocytes with a glucose consumption test.

The increase of glycolysis in mitogen-stimulated lymphocytes was used to quantify lymphoblast transformation. Results correlated well with those by common methods, i.e. morphological evaluation and [3H]thymidine incorporation. The advantage of the glucose consumption test is that it registers the entire event of lymphocyte proliferation whereas other methods evaluate only viable transformed cells at the end of culture.

Purine nucleoside phosphorylase, a possible histochemical marker for T-cells in man.

A procedure is described for the histochemical detection of purine nucleoside phosphorylase (PNP) activity in circulating lymphocytes of man. The number of PNP-positive cells, as evaluated on smears of Ficoll--Hypaque purified cells, correlated well with the number of E-rosette-forming cells of the same blood samples of healthy and diseased people with normal or abnormal numbers of E-rosettes. In healthy people, the number of PNP-positive cells was within the range of 70-80% of the total lymphocyte population, whilst the corresponding E-rosette-forming cells were scored between 60-75%. Patients with unusually low or high E-rosettes had equally low or high numbers of PNP-reactive cells. More substantial evidence for the presence of PNP activity in T-cells and not in B cells was gathered from experiments in which PNP activity and surface membrane immunoglobulins (SMIg) were simultaneously demonstrated on the same preparation. These results showed, on the one hand, that the bulk of lymphocytes that are reactive for PNP do not reveal SMIg and, on the other hand, that most Ig-bearing cells were unreactive for PNP.

The effects of short-term treatment with levamisole on cytokines in volunteers and cancer-patients.

In search for clues to the potential immunomodulating mechanism of action of levamisole which might be used as monitoring parameters, we have determined a variety of cytokines in the peripheral blood of volunteers and carcinoma patients before and after a single or a 3-day-treatment with 150 mg/day. In cancer patients no changes could be detected 4 days after a 3-day-treatment course in the levels of TNF-alpha, IL-1beta, IL-2 or IL-6. In a placebo-controlled volunteer study the same treatment did not affect the levels of beta2-microglobulin, IL-1beta, IL-1alpha, IL-2 or IL-6. However, 24hr after the last treatment the concentration of neopterin was slightly but significantly increased and the concentration of soluble IL-2 receptors decreased. A single treatment failed to produce such an effect. It is suggested that the measurement of neopterin and soluble IL-2 receptors may provide useful information in future trials.

Unchanged levels of interleukins, neopterin, interferon-gamma and tumor necrosis factor-alpha in cerebrospinal fluid of patients with dementia of the Alzheimer type.

Several histopathological studies suggest that amyloidogenesis in dementia of the Alzheimer type is accompanied by activated glia and glia-derived cytokines, leading to chronic, self-propagating, cytokine-mediated molecular and cellular reactions. As studies regarding inflammatory changes in cerebrospinal fluid of patients with dementia of the Alzheimer type has been inconclusive, we set up a prospective study to assess cerebrospinal fluid levels of interleukin-1beta, interleukin-6, interleukin-10, interleukin-12, soluble interleukin-2 receptor, interferon-gamma, tumor necrosis factor-alpha and neopterin in 20 patients with dementia of the Alzheimer type and 20 age- and sex-matched controls. Comparing both groups, no significant differences in concentrations and specific activities could be revealed. An additional 22 patients were included to enlarge the study population. No statistically significant differences were shown comparing patients (n=42) with the control group (n=20). We conclude that the immune-mediated inflammatory changes found in histopathological studies are not reflected in cerebrospinal fluid of patients with dementia of the Alzheimer type. Probably, cytokine production appears very localized in the central nervous system, not allowing representative detection in cerebrospinal fluid. Further studies assessing cytokine levels in various regions of central nervous system of patients with dementia of the Alzheimer type will be of interest to confirm this hypothesis.

Oxatomide in the treatment of various allergic diseases.

The use of oral oxatomide (30 to 360 mg per day) for the treatment of allergic conditions of the bronchi, skin and gastro-intestinal tract was investigated in a total of 70 subjects. Therapeutic results were evaluated at intervals ranging between 1 and 16 months. Symptomatic improvements were scored globally, forced expiratory volume in 1 second was measured in asthmatic patients, and the lesions of atopic dermatitis were rated according to a modified Clendening scale. The results suggest that oxatomide was particularly effective in the treatment of allergic rhinitis and skin allergies. Allergic asthma responded fairly well in patients with a short history of disease and gastro-intestinal conditions reacted moderately, with haemorrhagic rectitis responding better than gastritis. These findings warrant further controlled trials of oxatomide in such conditions.

Levamisole in the treatment of cancer: anything new? (Review).

Recently, levamisole combined with 5-FU was shown definitively to increase the survival of patients after surgery for colon cancer (9, 10). In the light of these findings the experimental and clinical findings with levamisole in the field of oncology are reviewed. The conclusion is reached that levamisole has proven activity, although its mechanism of action remains elusive. The progress that has been made in our understanding of immunology in general, the remarkable advance in experimental and diagnostic tools and the recent emergence of new indications of levamisole's interaction with immunosuppressive factors and interleukins all together warrant sufficient optimism to engage in a renewed clinical and experimental research effort. The outcome may be rewarding not only in terms of optimised treatment of patients with levamisole but also a more rational search for more potent successors may become feasible.

Enumeration of T-lymphocytes and T-lymphocyte subsets in rheumatoid arthritis using monoclonal antibodies.

The number of T-lymphocytes and T-lymphocyte subsets was measured in peripheral blood of 51 patients with rheumatoid arthritis. T-lymphocytes were counted by E-rosette tests and by the immunogold staining method with OKT3.PAN monoclonal antibody. Helper and suppressor T-lymphocytes were determined by the immunogold staining method with OKT4.IND and OKT8.SUP monoclonal antibody. The relative and absolute numbers of T-lymphocytes and helper T-lymphocytes in peripheral blood of patients with RA did not differ significantly from those in the blood of healthy subjects. However, the relative and absolute numbers of suppressor T-cells were significantly lower in patients with RA than in healthy subjects. The decrease of suppressor T-cells in the blood of patients with RA dit not correlate with the activity of the disease nor the presence of the rheumatoid factor.

The effect of a combined administration of ridogrel and ketanserin in patients with intermittent claudication.

After a 1-month placebo run-in phase, 27 patients with proven peripheral arterial obstructive disease participated in a double blind placebo controlled study and were divided in 3 groups, receiving either placebo, ridogrel 300 mg b.i.d. (a combined thromboxane synthase and receptor blocking agent) or a combination of ridogrel 300 mg b.i.d. and ketanserin 20 mg t.i.d. (a 5-HT2 serotonergic receptor antagonist) for a period of 1 month. In both active treatment groups, serum levels of thromboxane B2 decreased significantly to 3% of baseline. The levels of 6-keto-prostaglandin F1 alpha and prostaglandin F2 alpha increased two- to three-fold and levels of prostaglandin E2 6 times. Platelet aggregation induced by collagen and by U 46619, a thromboxane A2 mimetic, were significantly inhibited by both treatment regimen. Template bleeding times were significantly prolonged but plasma fibrinogen levels and the activated partial thromboplastin time were not affected with the active treatments. No such changes were seen with placebo. An inhibition of the serotonin-induced platelet aggregation was only seen in the ketanserin-treated group. In a 3-month open follow-up period during combined treatment with ridogrel and ketanserin in 22 patients, the effects on platelet function and prostanoids were maintained. The total duration of the walking distance on a treadmill improved significantly from 323 +/- 53 seconds to 399 +/- 48 seconds and the onset of claudication pain improved significantly from 121 +/- 29 seconds to 212 +/- 44 seconds, whereas the maximal drop of the post-exercise ankle/arm pressure gradient markedly and significantly improved from a control value of 0.38 +/- 0.05 to 0.51 +/- 0.05. These findings suggest that a combination of ridogrel and ketanserin may be of therapeutic value in the treatment of intermittent claudication.

Comparative cardiac haemodynamics of bisoprolol, celiprolol, carvedilol and nebivolol in normal volunteers.

Nebivolol is a novel selective beta 1-adrenergic antagonist with an unusual haemodynamic profile. It improves left ventricular function in normals and in patients with a damaged left ventricle. We compared the cardiac effects of a 14-day treatment period with 10 mg o.d. of bisoprolol, 400 mg o.d. of celiprolol, 25 mg o.d. of carvedilol and 5 mg o.d. of nebivolol in a placebo-controlled crossover study in 7 volunteers with a mean age of 39 (range 30-53) years. Cardiac haemodynamics were assessed serially by means of systolic time intervals. The ratio of the preejection period to the left ventricular ejection time (PEP/LVET) was used as a indirect measure of left ventricular performance. The results show that the PEP/LVET is a very sensitive and reproducible index of left ventricular function. During treatment with placebo and bisoprolol no changes occurred; during treatment with celiprolol and carvedilol a significant but transient decrease of PEP/LVET occurred, and only during treatment with nebivolol a long-lasting and significant decrease of PEP/LVET occurred. With bisoprolol an increase of PEP and QS2c (total electromechanical systole) was observed, indicative of a negative inotropic effect. In conclusion, nebivolol, in contrast with both classical and vasodilating beta-blocking agents, substantially improves left ventricular function, possibly due to an improvement of diastolic function and left ventricular compliance, which may be of therapeutical value in the treatment of congestive heart failure.

The antihypertensive and cardiac hemodynamic effects of nebivolol.

Acute, subacute, and chronic treatment with nebivolol, a novel beta 1-selective adrenergic antagonist, significantly lowered systolic and diastolic blood pressure and heart rate in patients with essential hypertension. No orthostatism and bradycardia were reported. A comparison between a normal control group and 23 hypertensive patients revealed that the ratio between the preejection period (PEP) and the left ventricular ejection time (LVET) of the systolic time intervals (STI) was significantly increased in the hypertensive patients, owing to a prolongation of the PEPc (PEP corrected for heart rate). Treatment with nebivolol 5 mg once a day significantly improved the PEP/LVET, in acute conditions from 0.42 +/- 0.023 to 0.39 +/- 0.018, after one month of treatment from 0.40 +/- 0.013 to 0.36 +/- 0.013 and after one year of treatment from 0.41 +/- 0.012 to 0.36 +/- 0.010, owing to a significant shortening of the PEPc. There was no correlation between changes of blood pressure and changes of STI. Diastolic dysfunction is an early finding in hypertension and may well be reflected in the prolongation of the PEPc. The improvement of left ventricular performance, as measured with STI, suggests that treatment with nebivolol may favorably influence the underlying diastolic dysfunction and be of therapeutic value for hypertensive patients with left ventricular damage.

Subacute hemodynamic effects of nebivolol in man at rest and during exercise.

In a subacute experiment 7 apparently healthy volunteers received a daily oral dose of 5 mg nebivolol for seven days, followed by a seven-day washout period with placebo. From the first day during treatment with nebivolol, peak exercise heart rate and systolic blood pressure, as measured during a standardized submaximal treadmill exercise, significantly decreased by 15% and 19% respectively. A prolonged treatment for one week did not further increase the response of exercise heart rate and systolic blood pressure to nebivolol. However, the ratio of preejection period (PEPc) to left ventricular ejection time (LVETc), an indirect and valuable measure of left ventricular performance, progressively and significantly decreased during the seven-day treatment period with nebivolol from a mean value of 0.37 +/- 0.012 to 0.31 +/- 0.009. The improvement of systolic time intervals resulted from a shortening of the PEPc and a lengthening of the LVETc. At rest, heart rate did not change significantly with nebivolol, whereas both systolic and diastolic blood pressure gradually and significantly lowered. The postexercise LVETc significantly shortened during treatment with nebivolol, and this shortening was more pronounced after seven days of treatment. After discontinuation of treatment with nebivolol, all these effects persisted for more than thirty hours after the last intake and gradually returned to pretreatment values thereafter. From these data it appears that nebivolol effectively reduces blood pressure at rest and during exercise in healthy volunteers, beneficially influencing preload and afterload, as measured by systolic time intervals.(ABSTRACT TRUNCATED AT 250 WORDS)

Hemodynamic effects of nebivolol in men: comparison of radionuclide angiocardiography with systolic time intervals.

In a subacute experiment the authors studied the effects of a fourteen -day treatment with nebivolol, 5 mg once a day, in 10 healthy male volunteers with a mean age of thirty-one, twenty-five to thirty-nine years, by comparing the results of the resting ratio of the preejection period (PEP) to the left ventricular ejection time (LVET), as measured by systolic time intervals (STI), with the results obtained by equilibrium radionuclide angiocardiography (ERNA), using technetium 99m-labeled autologous red blood cells as a marker. A submaximal treadmill exercise test performed before and during treatment demonstrated that nebivolol significantly (p less than 0.01) reduced peak exercise heart rate and systolic blood pressure from a mean value of 158 +/- 5.4 bpm to 131 +/- 4.3 bpm and from 171 +/- 4.9 mmHg to 144 +/- 4.5 mmHg respectively. The data from the STI and ERNA were calculated and analyzed independently by two observers. A highly significant (r = 0.8182, p = 0.0038) correlation was found between the changes of stroke volume (SV) and PEPc/LVETc during treatment with nebivolol. Furthermore end-diastolic volume significantly(p = 0.03) increased from a mean value of 177 +/- 10.1 ml to 198 +/- 6 ml and stroke volume significantly (p = 0.01) increased from 120 +/- 6.8 ml to 136 +/- 6.3 ml. Systemic vascular resistance tended to decrease from a mean value of 11.4 +/- 1.28 units to 10.6 +/- 1.10 units. No changes could be observed either in ejection fraction or in cardiac output.(ABSTRACT TRUNCATED AT 250 WORDS)

Comparison of the subacute hemodynamic effects of atenolol, propranolol, pindolol, and nebivolol.

In an observer-blind four-way crossover study, 7 healthy volunteers received in random sequence, one month apart, atenolol 100 mg od, propranolol (slow release) 160 mg od, pindolol 5 mg tid, and nebivolol 5 mg od for a period of seven days, followed by a single-blind placebo washout period of seven days. The decrease of peak exercise heart rate and systolic blood pressure was significant (p = 0.02) and comparable for the four drugs studied and varied between 15% and 23% for heart rate and between 15% and 20% for systolic blood pressure. Although no statistically significant difference was observed among the four drug regimens, the decrease of peak exercise heart rate was less pronounced with nebivolol than with the three reference beta-blocking agents. The ratio of the preejection period (PEPc) to the left ventricular ejection time (LVETc), an indirect measure of left ventricular performance, tended to increase with atenolol and propranolol and remained unchanged with pindolol. PEPc/LVETc progressively and significantly improved with nebivolol from a control value of 0.37 +/- 0.012 to 0.31 +/- 0.009 (p = 0.03) after seven days of treatment, owing to a decrease in PEPc and an increase in LVETc, suggestive of a combined effect both on preload and afterload. Postexercise LVETc, an index of the intrinsic positive inotropy of exercise, was significantly suppressed by atenolol, propranolol, and pindolol, but not during treating with nebivolol. These data suggest that nebivolol is a beta 1-selective adrenergic antagonist with an unusual hemodynamic profile, probably improving left ventricular compliance.

The antihypertensive effects of a pure and selective serotonin-receptor blocking agent (R 41 468) in elderly patients.

In a first experiment, an acute intravenous administration of 10 mg R 41 468, a pure serotonin-receptor blocking agent with high selectivity for blood vessels and thrombocytes and devoid of central effects, dramatically reduced systolic and diastolic blood pressure in 23 elderly hypertensive patients. Heart rate and cardiac output remained virtually unchanged. In a second double-blind placebo-controlled cross-over study a highly significant decrease of systolic and diastolic blood pressure was obtained in 14 elderly hypertensive patients during an 8-day oral treatment with 40 mg t.i.d. of R 41 468. No serious side-effects were observed. An oral maintenance therapy with R 41 468 for 3 weeks showed a further reduction of blood pressure, resulting in a normalization of blood pressure, taking into account the advanced age of the patients. R 41 468 most probably acts by decreasing the venous capacitance bed constriction. Essential hypertension might be causally related to an impairment of venous function, in which serotonin might be an important pressor factor.

Domperidone in the treatment of dyspepsia: a double-blind placebo-controlled study.

Domperidone, at a dosage of 20 mg t.d.s before meals, in a double-blind, crossover, placebo-controlled trial reduced the level of the symptoms of dyspepsia by 76% compared to a 16% reduction with placebo. This difference was statistically significant (p less than 0.001). Thirteen of the fourteen patients in the study preferred domperidone to placebo. Four patients in the active treatment period and one in the placebo complained of mild side-effects.

Effects of levamisole treatment in cancer patients.

Twenty-six controlled prognostic evaluations of the adjuvant use of levamisole in cancer are reviewed. The results favor intermittent administration of levamisole in a dosage that is adapted to the patient's weight or body surface. Early treatment is indicated, but synchronous treatment with cytotoxic therapies is to be avoided. The best results have been achieved in advanced but still potentially curable patients. Major toxicity occurs very seldom and measures are suggested to further characterize the few patients who are at risk of developing allergic agranulocytosis, a potentially life-threatening side effect.