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F Lejeune

Publications and source records attributed to F Lejeune.

At least 55 records · Page 3Linked to original sources
PubMed1998

Pharmacokinetics of temozolomide in association with fotemustine in malignant melanoma and malignant glioma patients: comparison of oral, intravenous, and hepatic intra-arterial administration.

PURPOSE: Depletion of the DNA repair enzyme O6-alkylguanine-DNA alkyltransferase (AT) has been shown to increase tumor sensitivity to chloroethylnitrosoureas. Temozolomide (TMZ), an analogue of dacarbazine, can deplete AT, suggesting that it may be used to sensitize tumors to chloroethylnitrosoureas. However, the influence of nitrosoureas on the pharmacokinetics of TMZ is unknown, and a pilot study was performed to assess the pharmacokinetics of TMZ given via, various routes to 29 patients (27 malignant melanomas, 2 gliomas) with or without sequential administration of i.v. fotemustine. METHODS: On day 1, TMZ was given intravenously (i.v.), orally (p.o.), or by intra-hepatic arterial infusion (h.i.a.) at four ascending dose levels (150 to 350 mg/m2 per day). On day 2 the same dose of TMZ was given by the same route (or by another route in six patients for determination of its bioavailability), followed 4 h later by fotemustine infusion at 100 mg/m2. Plasma and urinary levels of TMZ were determined on days 1 and 2 by high-performance liquid chromatography after solid-phase extraction. RESULTS: The pharmacokinetics of i.v. TMZ appeared linear, with the area under the curve (AUC) increasing in proportion to the dose expressed in milligrams per square meter (r = 0.86 and 0.91 for days 1 and 2, respectively). The clearance after i.v. administration was 220 +/- 48 and 241 +/- 39 ml/min on days 1 and 2, respectively. The apparent clearance after p.o. and h.i.a. administration was 290 +/- 86 and 344 +/- 77 ml/min, respectively. The volume of distribution of TMZ after i.v., p.o., and h.i.a. administration was 0.4, 0.6, and 0.6 l/kg on day 1 and 0.5, 0.5, and 0.6 l/kg on day 2, respectively. The absolute bioavailability of TMZ was 0.96 +/- 0.1, regardless of the sequence of the i.v.-p.o. or p.o.-i.v. administration, confirming that TMZ is not subject to a marked first-pass effect. A comparison of TMZ pharmacokinetics after i.v. and h.i.a. treatment at the same infusion rate revealed little evidence of hepatic extraction of TMZ. However, the systemic exposure to TMZ (AUC) appeared to decrease at a lower infusion rate. TMZ excreted unchanged in the urine accounted for 5.9 +/- 3.4% of the dose, with low within-patient and high interpatient variability. TMZ crosses the blood-brain barrier and the concentration detected in CSF amounted to 9%, 28%, and 29% of the corresponding plasma levels (three patients). The equilibrium between plasma and ascitic fluid was reached after 2 h (assessed in one patient). CONCLUSION: The sequential administration of fotemustine at 4 h after TMZ treatment had no clinically relevant influence on the pharmacokinetics of TMZ. The potential clinical effect of TMZ given by h.i.a. or by locoregional administration has yet to be established, as has the impact of the infusion duration on patients' tolerance and response rate.

Administration, Oral↗
PubMed1998

Ten-year results of a strategy combining three cycles of ABVD and high-dose extended irradiation for treating Hodgkin's disease at advanced stages.

BACKGROUND: The treatment of Hodgkin's disease (HD) at advanced stages relies mainly upon multi-agent chemotherapies (CT), while the role of radiation therapy has not been definitely identified. The aim of this report is to analyze the 10-year results of a prospective study including 133 patients with HD clinical stages (CS) IIIA to IVB treated by three monthly courses of ABVD (adriamycin, bleomycin, vinblastin, and dacarbazine) followed by high-dose subtotal or total lymphoid irradiation [(S)TLI]. PATIENTS AND METHODS: From 1 October 1981 to 30 September 1988, 133 adult patients with HD CS IIIA (45), IIIB (33), IVA (seven) and IVB (48) were entered in the non-randomized multicentric prospective trial POF81/34. The number of involved nodal areas (NINA), and the number of visceral sites (NVIS) involved were registered in all patients; patients with bulky mediastinal tumor (BuMT) (mediastinal mass ratio > or = 0.45) were also identified. All patients received three monthly cycles of ABVD. Patients in complete remission (CR) or partial remission (PR) after completion of CT received a (S)TLI including the spleen (involved sites 40 Gy, non-involved 30 Gy); initially involved lung(s) and liver received 18 and 20 Gy, respectively; and patients not in CR or PR after CT or RT received salvage treatments. Univariate and multivariate analyses were performed to identify the factors contributing significantly to the prognosis; initial characteristics, as well as status after the three cycles of CT, were entered in the model. RESULTS: Of the 133 patients, 74 (55.6%) entered in CR after CT and 116 (87.2%) after completion of radiation therapy. Ten-year freedom from progression (FFP), freedom from tumor mortality (FFTM) and survival rates were 70.4%, 78.9% and 70.6%, respectively. According to univariate analysis the NVIS (< or = one vs. > or = two) was the only initial factor simultaneously influencing 10-year FFP (73.9% vs. 38.2%) FFTM (82.5 vs. 34.1%) and survival (73.5% vs. 17.3%) rates; on the other hand, the NINA (< or = four vs. > or = five) influenced FFP (81.4% vs. 60.7%) and FFTM rates (87.3% vs. 71.4%) while symptoms (A vs. B) influenced FFP (80.7% vs. 63.3%) and survival (82.8% vs, 61.2%) rates. Finally, age (< 40 vs. > or = 40) influenced survival rate only (79.2% vs. 50%). According to multivariate analysis, NVIS and NINA had an independent impact on FFP and FFTM, while survival was modified by the NVIS and age. The post-CT status (CR vs. no CR) had a major impact on FFP (85.3% vs. 64.9%) FFTM (92.1% vs. 63.3%) as well as on survival (78.6% vs. 54.7%) rates in both univariate and multivariate analyses. Complications of therapy were mainly due to RT: 11 patients acquired second malignancies, six developed lung fibrosis or severe pulmonary infections, three developed intestinal obstructions and six developed angina pectoris or carotid stenosis. CONCLUSIONS: Tumor burden (identified by the number of involved nodal areas and the number of visceral sites) and the response to initial CT were the two independent factors influencing the outcome of this group of 133 patients with HD, CSIII and IV treated by three cycles of ABVD followed by high-dose [(S)TLI].

Adult↗
PubMed1998

[Treatment of polycythemia. II.--Comparison of hydroxyurea with pipobroman in 294 patients less than 65 years of age].

AIMS: To compare by a prospective study in low risk polycythemia vera (PV) patients alone two drugs: hydroxyurea and pipobroman. Toxicity, efficiency, and leukemogenic potential were studied. PATIENTS: 294 patients with a documented PV, aged less than 65 years, have been included since 1980 in a prospective study comparing hydroxyurea and pipobroman. Blood cell counts were performed every two months and a clinical evaluation by a specialist was obtained every four or six months. RESULTS: Hematologic toxicity of both drugs was higher than expected, requiring strict surveillance. These drugs were tolerated in some (gastric pain and diarrhea on pipobroman, buccal aphtosis and chronic leg ulcers on hydroxyurea), leading to a change of arm in 10% of the cases. Hydroxyurea did not control the megakaryocitic hyperplasia in 40% of the cases, which probably explains a high rate of progression to myelofibrosis with myeloid metaplasia in this arm. Both drugs were leukemogenic with an actuarial risk of about 15% at the 15th year, not significantly lower than that observed in the 32P treated patients. A significant risk of cutaneous malignancy was observed in the hydroxyurea arm. The mean expectancy of life cannot yet be accurately evaluated, but seems significantly lower than that of the reference population. CONCLUSION: The treatment of PV by hydroxyurea or pipobroman has to account for these results less optimistic than those traditionally well-known to hematologists and internists.

Adult↗
PubMed1998

S 16924 ((R)-2-[1-[2-(2,3-dihydro-benzo[1,4] dioxin-5-Yloxy)-ethyl]-pyrrolidin-3yl]-1-(4-fluoro-phenyl)-ethanone), a novel, potential antipsychotic with marked serotonin (5-HT)1A agonist properties: I. Receptorial and neurochemical profile in comparison with clozapine and haloperidol.

S 16924 showed a pattern of interaction at multiple (>20) native, rodent and cloned, human (h) monoaminergic receptors similar to that of clozapine and different to that of haloperidol. Notably, like clozapine, the affinity of S 16924 for hD2 and hD3 receptors was modest, and it showed 5-fold higher affinity for hD4 receptors. At each of these sites, using a [35S]GTPgammaS binding procedure, S 16924, clozapine and haloperidol behaved as antagonists. In distinction to haloperidol, S 16924 shared the marked affinity of clozapine for h5-HT2A and h5-HT2C receptors. However, an important difference to clozapine (and haloperidol) was the high affinity of S 16924 for h5-HT1A receptors. At these sites, using a [35S]GTPgammaS binding model, both S 16924 and clozapine behaved as partial agonists, whereas haloperidol was inactive. In vivo, the agonist properties of S 16924 at 5-HT1A autoreceptors were revealed by its ability to potently inhibit the firing of raphe-localized serotoninergic neurones, an action reversed by the selective 5-HT1A receptor antagonist, WAY 100,635. In contrast, clozapine and haloperidol only weakly inhibited raphe firing, and their actions were resistant to WAY 100,635. Similarly, S 16924 more potently inhibited striatal turnover of 5-HT than either clozapine or haloperidol. Reflecting its modest affinity for D2 (and D3) autoreceptors, S 16924 only weakly blocked the inhibitory influence of the dopaminergic agonist, apomorphine, upon the firing rate of ventrotegmental area-localized dopaminergic neurones. Further, S 16924 only weakly increased striatal, mesolimbic and mesocortical turnover of dopamine (DA). Clozapine was, similarly, weakly active in these models, whereas haloperidol, in line with its higher affinity at D2 (and D3) receptors, was potently active. In the frontal cortex (FCX) of freely moving rats, S 16924 dose-dependently reduced dialysate levels of 5-HT, whereas those of DA and NAD were dose-dependently increased in the same samples. In contrast, although S 16924 also suppressed 5-HT levels in the striatum and nucleus accumbens, DA levels therein were unaffected. Clozapine mimicked this selective increase in DA levels in the FCX as compared to striatum and accumbens. In contrast, haloperidol modestly increased DA levels in the FCX, striatum and accumbens to the same extent. In distinction to S 16924, clozapine and haloperidol exerted little influence upon 5-HT levels. Finally, the influence of S 16924 upon FCX levels of 5-HT, DA (and NAD) was attenuated by WAY 100,635. In conclusion, S 16924 possesses a profile of interaction at multiple monoaminergic receptors comparable to that of clozapine and distinct to that of haloperidol. In addition, S 16924 is a potent, partial agonist at 5-HT1A receptors. Correspondingly, acute administration of S 16924 decreases cerebral serotoninergic transmission and selectively reinforces frontocortical as compared to subcortical dopaminergic transmission. In line with these actions, S 16924 shows a distinctive profile of activity in functional (behavioral) models of potential antipsychotic activity (companion paper).

Animals↗
PubMed1998

S 18126 ([2-[4-(2,3-dihydrobenzo[1,4]dioxin-6-yl)piperazin-1-yl methyl]indan-2-yl]), a potent, selective and competitive antagonist at dopamine D4 receptors: an in vitro and in vivo comparison with L 745,870 (3-(4-[4-chlorophenyl]piperazin-1-yl)methyl-1H-pyrrolo[2, 3b]pyridine) and raclopride.

The novel benzoindane S 18126 possessed > 100-fold higher affinity at cloned, human (h) D4 (Ki = 2.4 nM) vs. hD2 (738 nM), hD3 (2840 nM), hD1 (> 3000 nM) and hD5 (> 3000 nM) receptors and about 50 other sites, except sigma1 receptors (1.6 nM). L 745,870 similarly showed selectivity for hD4 (2.5 nM) vs. hD2 (905 nM) and hD3 (> 3000 nM) receptors. In contrast, raclopride displayed low affinity at hD4 (> 3000 nM) vs. hD2 (1.1 nM) and hD3 receptors (1.4 nM). Stimulation of [35S]-GTPgammaS binding at hD4 receptors by dopamine (DA) was blocked by S 18126 and L 745,870 with Kb values of 2.2 and 1.0 nM, respectively, whereas raclopride (> 1000 nM) was inactive. In contrast, raclopride inhibited stimulation of [35S]-GTPgammaS binding at hD2 sites by DA with a Kb of 1.4 nM, whereas S 18126 (> 1000 nM) and L 745,870 (> 1000 nM) were inactive. As concerns presynaptic dopaminergic receptors, raclopride (0.01-0.05 mg/kg s.c. ) markedly enhanced DA synthesis in mesocortical, mesolimbic and nigrostriatal dopaminergic pathways. In contrast, even high doses (2. 5-40.0 mg/kg s.c.) of S 18126 and L 745,870 were only weakly active. Similarly, raclopride (0.016 mg/kg i.v.) abolished inhibition of the firing rate of ventrotegmental dopaminergic neurons by apomorphine, whereas even high doses (0.5 mg/kg i.v.) of S 18126 and L 745,870 were only weakly active. As regards postsynaptic dopaminergic receptors, raclopride potently (0.01-0.3 mg/kg s.c.) reduced rotation elicited by quinpirole in rats with unilateral lesions of the substantia nigra, antagonized induction of hypothermia by PD 128, 907, blocked amphetamine-induced hyperlocomotion and was effective in six further models of potential antipsychotic activity. In contrast, S 18126 and L 745,870 were only weakly active in these models (5.0-> 40.0 mg/kg s.c.). In six models of extrapyramidal and motor symptoms, such as induction of catalepsy, raclopride was likewise potently active (0.01-2.0 mg/kg s.c.) whereas S 18126 and L 745,870 were only weakly active (10.0-80.0 mg/kg s.c.). In freely moving rats, raclopride (0.16 mg/kg s.c.) increased levels of DA by + 55% in dialysates of the frontal cortex. However, it also increased levels of DA in the accumbens and striatum by 70% and 75%, respectively. In contrast to raclopride, at a dose of 0.16 mg/kg s.c. , neither S 18126 nor L 745,870 modified frontal cortex levels of DA. However, at a high dose (40.0 mg/kg s.c.), S 18126 increased dialysate levels of DA (+ 85%) and noradrenaline (+ 100%), but not serotonin (+ 10%), in frontal cortex without affecting DA levels in accumbens (+ 10%) and striatum (+ 10%). In conclusion, S 18126 and L 745,870 behave as potent and selective antagonists of cloned, hD4 vs. other dopaminergic receptor types in vitro. However, their in vivo effects at high doses probably reflect residual antagonist actions at D2 (or D3) receptors. Selective blockade of D4 receptors was thus associated neither with a modification of dopaminergic transmission nor with antipsychotic (antiproductive) or extrapyramidal properties. The functional effects of selective D4 receptor blockade remain to be established.

Animals↗
PubMed1998

A comparative in vitro and in vivo pharmacological characterization of the novel dopamine D3 receptor antagonists (+)-S 14297, nafadotride, GR 103,691 and U 99194.

The benzofurane (+)-S 14297, the benzamide nafadotride, the aminoindane U 99194 and the arylpiperazine GR 103,691 have been proposed as "selective" antagonists at dopamine D3 vs. D2 receptors. Herein, we compared their in vitro affinities and in vivo actions to those of the aminotetralin D3 antagonists (+)-AJ 76 and (+)-UH 232. Affinities at recombinant, human (h)D3 and/or hD2 sites were determined by employing the mixed D2/D3 antagonist [125I]-iodosulpride and the preferential D3 ligands [3H]-(+)-PD 128, 907 and [3H]-(+)-S 14297. [3H]-(+)-PD 128,907, [3H]-(+)-S 14297 and [125I]-iodosulpride yielded an essentially identical pattern of displacement at D3 sites, which suggests that they recognize the same population of receptors. The rank order of potency (Ki values in nM vs. [3H]-(+)-PD 128,907) was GR 103,691 (0.4) approximately nafadotride (0.5) > haloperidol (2) approximately (+)-UH 232 (3) approximately (+)-S 14297 (5) > (+)-AJ 76 (26) > U 99194 (160). The rank order of preference (Ki ratio, D2:D3) for D3 receptors (labeled by [3H]-PD 128,907) vs. D2 sites (labeled by [125I]-iodosulpride) was (+)-S 14297 (61) approximately GR 103,691 (60) > U 99194 (14) > nafadotride (9) approximately (+)-UH 232 (8) approximately (+)-AJ 76 (6) > haloperidol (0.2). (+)-S 14297 and GR 103,691 also showed greater than 100-fold selectivity at dopamine hD3 vs. hD4 and hD1 sites. However, GR 103,691 showed marked affinity for serotonin1A receptors (5.8 nM) and alpha-1 adrenoceptors (12.6 nM). In vivo, all antagonists except GR 103,691 prevented the induction of hypothermia by (+)-PD 128,907 (0.63 mg/kg s.c.) and a further preferential D3 agonist, (+)-7-OH-DPAT (0.16 mg/kg s.c.). On the other hand, haloperidol, (+)-AJ 76, (+)-UH 232 and nafadotride all induced catalepsy in rats, whereas (+)-S 14297, U 99194 and GR 103,691 were inactive. Haloperidol, (+)-AJ 76, (+)-UH 232, nafadotride and (weakly) U 99194 also enhanced prolactin secretion and striatal dopamine synthesis, whereas (+)-S 14297 and GR 103,691 were inactive. However, despite its high affinity at 5-HT1A receptors and alpha-1 adrenoceptors, both of which are present on raphe-localized serotonergic neurons, GR 103,691 (0.5 mg/kg i.v.) failed to influence their basal firing rate or the inhibition of their electrical activity by the 5-HT1A agonist (+/-)-8-OH-DPAT (0.005 mg/kg i.v.), a result that casts doubt on its activity in vivo. In conclusion, both (+)-S 14297 and GR 103,691 are markedly selective ligands that permit the characterization of actions at hD3 vs. hD2 receptors in vitro, but (+)-S 14297 appears to be of greater utility for the evaluation of their functional significance in vivo. Nevertheless, to develop a better understanding of the respective roles of dopamine D3 and D2 receptors, we need additional, chemically diverse antagonists of improved potency and selectivity.

2-Naphthylamine↗
PubMed1998

[Alternative medicine: viewpoints of a sociologist and an oncologist].

There is an increasing interest for Alternative Medicine among the lay-man and some physicians. However, no critical nor constructive discussion is happening between them and Scientific Medicine. The scientific evaluation of Alternative Medicine is hampered by the difficulty to transfer the various medical paradigms, and some practitioners are not MDs. Despite this impediment, an evaluation must take place, with adapted criteria, without going to much away from scientific standards. Health officers from several industrial countries are working on that topic. It will be of prime importance to aim at a consensus, and it should be regularly revisited.

Attitude of Health Personnel↗
PubMed1997

Systemic release of soluble TNF receptors after high-dose TNF in isolated limb perfusion.

Isolated limb perfusion (ILP) with high dose tumour necrosis factor (TNF), interferon gamma and melphalan (TIM) is an efficient treatment for patients with regionally advanced melanoma and sarcoma. In 44 patients, we determined the kinetics of soluble TNF receptors (sTNF-RI and RII) plasma concentrations, and correlated them with systemic TNF and interleukin 6 (IL-6) levels and shock. Seven patients treated conventionally by ILP without cytokine served as controls. Elevated levels of both sTNF-Rs were observed within 30 min after beginning of the TIM-ILP. A first peak of sTNF-Rs levels was observed 3 h after ILP and was followed by a rapid decrease reaching a nadir at 12-14 h post ILP. This first peak was followed by a second, long-lasting elevation of both sTNF-Rs levels persisting for 4 to 5 days after TIM-ILP. Patients treated by ILP without TNF/interferon gamma (IFN-gamma) had no detectable increase in either sTNF-Rs or in circulating TNF, demonstrating that the release of TNF-Rs was dependent upon the administration of TNF/IFN-gamma. High plasma levels of TNF and IL-6 were observed in patients that had more than 5% leakage during the TIM-ILP, but no significant correlation between TNF levels and the peak values of both sTNF-Rs was observed. The levels of TNF and IL-6 were, however, significantly related to each other. TNF systemic levels, but not sTNF-Rs concentrations, correlated significantly with the severity of the shock observed after TIM-ILP. Patients in which sTNF-RII concentration was in excess over circulating TNF, had no shock or grade I shock only, suggesting that sTNF-RII may play a protective, although limited, role in inhibiting activity of circulating TNF.

Chemotherapy, Cancer, Regional Perfusion↗
PubMed1997

Melanoma risk and residence in sunny areas. EORTC Melanoma Co-operative Group. European Organization for Research and Treatment of Cancer.

Melanoma risk among subjects from Germany, France and Belgium who had lived for 1 year or more in sunny climates was examined in a one-to-one unmatched case-control study conducted among white subjects 20 years old or more. A total of 412 consecutive patients with melanoma diagnosed from 1 January 1991 onwards, were derived from hospital registers; 445 controls were randomly chosen in the same municipality as the cases. After adjustment for host characteristics, melanoma risk associated with residence in a sunny area was 2.7 (95% CI: 1.4-5.2), increasing to 4.7 (95% CI: 1.4-13.5) if subjects sought a suntan when residing in sunny climates, and to 4.3 (95% CI: 1.7-11.1) if subjects arrived before the age of 10 years in the sunny area. Residence in sunny areas and recreational sun exposure seemed to combine their effects on melanoma risk. Increase in melanoma risk conveyed by deliberate sun exposure during adulthood was highest among subjects who had lived in sunny areas as a child or adolescent and lowest among subjects who had never resided in sunny areas. Our results support conclusions from migrant studies that indicated that childhood is a critical period of either vulnerability to solar radiation or more frequent exposures to melanoma risk factors. They also suggest that moderate sun exposure of an adult who was heavily sun exposed in childhood is associated with a higher melanoma risk than that of high sun exposure of an adult who was sun protected in childhood.

Adult↗
PubMed1997

Treatment of ocular melanoma metastatic to the liver by hepatic arterial chemotherapy.

PURPOSE: Ocular melanoma is characterized by a high rate of liver metastases and is associated with a median survival time less than 5 months. There is no standard treatment available. Treatment strategies have, without success, relied on the experience with metastatic cutaneous melanoma. The only effective treatment is chemoembolization using cisplatin and polyvinyl sponge, which has never become accepted on a large scale. The objective of the study was to establish prospectively the efficacy and toxicity of hepatic intraarterial fotemustine, a third-generation nitrosourea, in patients with liver metastases from ocular melanoma. PATIENTS AND METHODS: Thirty-one patients were subjected to laparotomy to place a totally implantable catheter into the hepatic artery and received fotemustine 100 mg/m2 as a 4-hour infusion, first once a week for four times and then, after a 5-week rest period, every 3 weeks until progression or toxicity. Cox regression models were used to assess the prognostic role of patient survival characteristics. RESULTS: Objective responses were observed in 12 of 30 assessable patients (40%; 95% confidence interval, 22% to 59%). The median duration of response was 11 months and the median overall survival time, 14 months. Lactate dehydrogenase (LDH) appeared to be the strongest prognostic factor for survival. Toxicity was minimal and treatment could be administered on an outpatient basis. CONCLUSION: The results of hepatic arterial chemotherapy with fotemustine produced a high response rate and survival similar to chemoembolization therapy. It involves no major toxicity and preserves the quality of life. To assess further its effectiveness, a randomized study to compare hepatic intraarterial versus intravenous chemotherapy is being planned.

Adult↗
PubMed1997

Interactions of (+)- and (-)-8- and 7-hydroxy-2-(di-n-propylamino)tetralin at human (h)D3, hD2 and h serotonin1A receptors and their modulation of the activity of serotoninergic and dopaminergic neurones in rats.

The aminotetralins, 8-hydroxy-2-(di-n-propylamino)tetralin (8-OH-DPAT) and 7-OH-DPAT behave as preferential agonists at serotonin (5-HT)1A and dopamine D3 and D2 receptors, respectively. In our study, we evaluated the influence of their (+)- and (-) isomers on the electrical activity of serotoninergic neurones of the dorsal raphe nucleus (DRN), which bear 5-HT1A autoreceptors, and of dopaminergic neurones of the ventral tegmental area (VTA), which possess inhibitory D3 and D2 receptors. These actions were compared to their in vitro interactions with cloned, human (h)5-HT1A, hD3 and hD2 receptors. In binding studies, racemic 8-OH-DPAT showed 100-fold selectivity for h5-HT1A vs. hD2 and hD3 receptors and there was little difference between its (+)- and (-)-isomers either in terms of their potency at 5-HT1A receptors or of their selectivity at 5-HT1A vs hD2/hD3 sites. Nevertheless, the (+)-isomer was markedly more efficacious than its (-)-counterpart in stimulating the binding of guanosine 5'-O-(3-[35S]thiotriphosphate) ([35S]-GTPgammaS) at h5-HT1A receptors, a measure of coupling to G-proteins; 90 vs. 57% maximal stimulation respectively, relative to 5-HT = 100%. Also the (+)-isomer was ca. 3-fold more potent than the (-)-isomer in inhibiting the firing rate of DRN neurones. These actions were abolished by the 5-HT1A antagonist, (-)-tertatolol, but unaffected by the hD2/hD3 antagonist, haloperidol. Whereas (+)-8-OH-DPAT stimulated VTA neurone firing with a bell-shaped dose response curve, the (-)-isomer only inhibited VTA firing. The (+)-isomer-induced stimulation was blocked by (-)-tertatolol but not haloperidol, whereas the (-)-isomer-induced inhibition was abolished by haloperidol and unaffected by (-)-tertatolol. In contrast to 8-OH-DPAT, the (+)- and (-)isomers of 7-OH-DPAT showed marked stereoselectivity inasmuch as the latter bound with 20-fold less potency than the former at hD3 and, at higher concentrations, hD2 receptors. Correspondingly, (+)-7-OH-DPAT was 20-fold more potent than (-)-7-OH-DPAT in reducing VTA firing. Concerning 5-HT1A receptors, the (+)-isomer showed 20-fold lower affinity than at hD3 receptors and, accordingly, it inhibited DRN firing at 20-fold higher doses than for inhibition of VTA firing. (-)-7-OH-DPAT showed even less (5-fold) selectivity for hD3 vs. 5-HT1A sites and for inhibition of VTA vs. DRN firing. The inhibition of VTA and DRN neurone firing by (+)-7-OH-DPAT was abolished by haloperidol and (-)-tertatolol, respectively. Finally, in line with this inhibition of DRN firing, both (+)- and (-)-7-OH-DPAT showed substantial efficacy ([35S]-GTPgammaS binding, 76 and 53%, respectively) at h5-HT1A receptors. In conclusion, for these substituted aminotetralins, stereospecificity is a more marked feature of interactions at hD3 (and hD2) than at h5-HT1A receptors and is more pronounced for 7- as compared to 8-OH-DPAT. Neither (+)- nor (-)-7-OH-DPAT show substantial selectivity for hD3 vs. 5-HT1A receptors and their inhibition of the firing of VTA as compared to DRN neurones is mediated by hD3/hD2 and 5-HT1A receptors, respectively. Finally, VTA neurones are stimulated by (+)-8-OH-DPAT via 5-HT1A receptors and inhibited by (-)-8-OH-DPAT via hD3 and/or hD2 receptors.

8-Hydroxy-2-(di-n-propylamino)tetralin↗
PubMed1997

Recombinant interleukin-2-based treatments for advanced melanoma: the experience of the European Organization for Research and Treatment of Cancer Melanoma Cooperative Group.

PURPOSE: This article reviews the currently available data on phase II and III trials regarding the efficacy of recombinant interleukin-2 (rIL-2)-based regimens in the treatment of stage IV melanoma, and discusses the rationale and outcome of past and currently ongoing rIL-2-based chemo-immunotherapy phase III trials conducted by the European Organization for Research and Treatment of Cancer Melanoma Cooperative Group. PATIENTS AND METHODS: In the first EORTC-MCG phase III trial, stage IV melanoma patients were stratified on the basis of serum lactate dehydrogenase levels and tumor burden and randomized to receive rIL-2 (decrescendo regimen) plus interferon-alpha (IFN-alpha) plus or minus cisplatin. In the second trial, which is still ongoing, patients are being randomized to receive dacarbazine plus cisplatin plus IFN-alpha plus or minus rIL-2. These studies are designed to address the relative impact of cisplatin and rIL-2, respectively, on response and survival. RESULTS: The addition of cisplatin to immunotherapy (rIL-2 plus IFN-alpha) doubled the response rate from 18% to 35%, but had no impact on survival. The second trial is still ongoing, and no data is available yet on the contribution of rIL-2 to response and survival. CONCLUSIONS: Review of the literature and the outcome of our first trial indicate that the addition of single-agent cisplatin or polychemotherapy regimens to immunotherapy with rIL-2 and/or IFN-alpha can dramatically improve response rates. However, what impact, if any, these regimens have on overall survival is not known at this time. We could not demonstrate a survival benefit in the cisplatin-containing arm in spite of the increased response rate. Chemotherapy may yield only short-term responses, whereas immunotherapy appears to yield durable complete responses in a subset of patients. Further randomized phase III studies are needed to identify the essential components in combination regimens and to determine whether the toxicity associated with these regimens is outweighed by potential cure or a significant survival benefit.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1997

[Covering of a thoraco-lumbar defect by omentoplasty].

With a case of thoraco-lumbar defect, the authors discuss about different procedures to cover it. In this place, the better procedure is certainly the latissimus dorsi flap, in all combinations. The indication for omentoplasty at this spinal site should not be performed by first intention but by exclusion of other procedures, as in the case considered by the authors. It was a 37-year-old man, paraplegic from the age of 16, with a deep chronic spinal wound, secondary to sepsis of a posterior segmental fixations. A staphylococcus aureus infection which developed as a surgical complication was initially treated with antibiotics and surgical cleaning procedures without removing instrumentation. However, the infection remained active and the material was finally removed. Spinal immobilisation was strengthened by external fixation. The area was cleared of all suspect material, including bone graft, leaving a wide back-wound open to the spine. Spontaneous healing was first attempted, but the size and the chronicity of the wound led us to use pedicled greater omentum to close the defect. The omentum was pedicled on the right gastroepiploic vessels and transferred to the back wound through the posterior abdominal wall muscles, next to the right kidney. This procedure allows rapid healing. In association with suitable antibiotics, it has prevented any recurrent infection after 18 months of follow-up. It was no feasible to cover the wound with a latissimus dorsi flap, considering the importance of this muscle in the movements of a paraplegic and considering the initial impossibility of removing the external fixation.

Adult↗
PubMed1997

Melanoma-reactive human cytotoxic T lymphocytes derived from skin biopsies of delayed-type hypersensitivity reactions induced by injection of an autologous melanoma cell line.

The expression by melanomas of multiple antigens that are recognized by specific MHC class I-restricted CTLs has been clearly demonstrated. The goal of many immunotherapy protocols being developed is, therefore, the induction and/or augmentation of CTLs specific for such antigens. One approach has been to immunize using irradiated autologous melanoma cells. Responses to this type of immunization and others are often subsequently measured by delayed-type hypersensitivity (DTH) reactions. The aim of this work was to characterize whether specific CTL responses occur at such DTH sites. Cutaneous DTH reactions were observed following injection of irradiated autologous melanoma cells expressing known tumor antigens. We isolated lymphocytes from biopsies of DTH reaction sites and could measure melanoma-specific CTL activity after 2-3 weeks of culture. The T-cell receptor-Vbeta repertoire of the cultured lymphocytes, assessed by flow cytometry, was highly skewed in both the CD4(+) and CD8(+) T-cell subsets. The repertoires were different among cultures derived from independent biopsies of simultaneous or subsequent DTH reaction sites and very different to that of fresh peripheral blood lymphocytes (PBLs) or PBLs cultured under the same conditions. No particular T-cell expansions dominated several DTH reaction sites, nor could they be detected in PBLs. It appears that T-cell responses to this type of immunization may be limited to the local microenvironment. Establishing the value of DTH reactions in determining levels of systemic antitumor immunity requires further investigation; however, such reactions may indicate a patient's competence to mount an antitumor immune response and enable the isolation of tumor-specific CTLs for use in tumor antigen identification.

Aged↗
PubMed1996

Protein tyrosine kinases in activation signal of human basophils through the immunoglobulin E receptor type l.

Human basophils activated through high-affinity immunoglobulin E (IgE) receptors (Fc epsilon RI) are involved in the late phase of the allergic reaction. To investigate the possible involvement of protein-tyrosine kinases in this activation we used human acute basophilic leukemia (ABL) cells in culture as well as a pure population of normal basophils in vitro-derived from human bone marrow precursor cells (HBMB). ABL cells were 50-80% basophils at various stages of maturation as assessed by staining, morphology, ultrastructure, and flow cytometry analysis, and only basophils in ABL cells expressed Fc epsilon RI. Aggregation of Fc epsilon RI by IgE and anti-IgE, IgE and antigen, or anti-Fc epsilon RI monoclonal antibodies on ABL cells or on HBMB, led to increased tyrosine phosphorylation of 120-, 100-, 80-, 72-, 50- to 65-, and 38-kDa substrates. Tyrosine phosphorylations in ABL cells were in basophils because 1) they were detected after a 5-s stimulation, 2) they were observed under conditions where mediator release is minimal, i.e., in the absence of extracellular calcium, 3) hapten addition during antigen stimulation resulted in almost total disappearance of tyrosine phosphorylations within 30 s. There was correlation between histamine release and tyrosine phosphorylation in anti-IgE dose-responses and in dose-responses of the tyrosine kinase inhibitor genistein. The tyrosine kinase p72syk was detected in the cells. Stimulation of ABL cells for 1 min resulted in extracellular calcium-independent tyrosine phosphorylation and activation of p72syk. Therefore, tyrosine kinases are involved in the early steps of human Fc epsilon RI signaling in basophils. Tyrosine kinases and their substrates could represent new potential therapeutic targets to prevent the development of the allergic reaction.

Aged↗
PubMed1996

Dopamine D3 (auto) receptors inhibit dopamine release in the frontal cortex of freely moving rats in vivo.

In freely moving rats, the novel, selective dopamine (DA) D3 receptor agonist PD 128,907 dose-dependently [effective dose (ED25) = 0.07 mg/kg, s.c.] reduced dialysate levels of DA in the frontal cortex, a structure innervated by the ventral tegmental area (VTA). This action of PD 128,907 (0.16 mg/kg, s.c.) was abolished by a selective DA D3 receptor antagonist S 14297 (1.25 mg/kg, s.c.), which alone did not modify levels of DA. In contrast to S 14297, its inactive distomer, S 17777, did not modify the actions of PD 128,907. In addition, PD 128,907 dose-dependently and potently inhibited the firing rate of VTA-localized neurons in anesthetized rats (ED50 = 0.001 mg/kg, i.v.). S 14297, but not S 17777, completely reversed the actions of PD 128,907 (0.005 mg/kg, i.v.) with a 50% inhibitory dose of 0.03 mg/kg, i.v. and did not itself significantly modify the firing rate. In conclusion, these data provide the first direct evidence that DA D3 (auto) receptors modulate (inhibit) the release of DA in the frontal cortex.

2-Naphthylamine↗
PubMed1996

Erythroblastic and/or megakaryoblastic leukemia in Down syndrome: treatment with low-dose arabinosyl cytosine.

PURPOSE: We report here the clinical response to low-dose arabinosyl cytosine (Ara-C) in seven children with Down syndrome (DS) and acute leukemia in which blast cells express markers of erythroid and/or megakaryoblastic lineages. Following an initial course of treatment with Ara-C, complete remission was obtained in all seven patients. Maintenance therapy with Ara-C was continued during complete remission. Four patients subsequently relapsed; the three others are disease-free. Based on these data, we suggest that when conventional therapy is contraindicated by associated malformations, low-dose Ara-C can be used for treating DS patients with erythroblastic or megakaryoblastic leukemia. The aim of this study was to assess the efficacy of low-dose Ara-C in treating megakaryoblastic and/or erythroblastic leukemia associated with DS. PATIENTS AND METHODS: Seven patients with DS presented with leukemia in which blast cells displayed early markers of the erythroblastic and/or megakaryoblastic lineage. Low-dose subcutaneous Ara-C (10 mg/m2 two times per day) was given for 21 days as induction therapy, followed by a 5-10-day course each month for 2 years as a maintenance treatment. RESULTS: Low-dose Ara-C treatment resulted in complete remission in all seven patients and in long-term disease-free survival in three patients. CONCLUSION: In cases in which conventional chemotherapy is contraindicated, low-dose Ara-C should be considered as a therapeutic alternative for treatment of DS-associated erythroblastic or megakaryocytic leukemia.

Antimetabolites, Antineoplastic↗