Pharmacokinetics and antipsychotic effect of remoxipride in chronic schizophrenic patients

Single dose pharmacokinetics and the antipsychotic effect of 4 weeks treatment with three fixed dose levels of remoxipride (a selective D(2) receptor antagonist) were studied in chronic, stable schizophrenic inpatients. After a placebo washout of 1 month, 15 patients entered the study. Of these, 11 patients received a single 50 mg oral dose of remoxipride for pharmacokinetic evaluations. All 15 patients were randomly assigned to treatment with oral remoxipride either 25 mg t.i.d., 50 mg t.i.d. or 100 mg t.i.d. for 4 weeks. Blood samples for remoxipride and prolactin assays were taken at 0, 0.33, 0.5, 0.66, 1.0, 1.5, 2, 3, 4, 8, 12, 24, 28, 32 and 48 h after drug intake. The pharmacokinetic characteristics were similar to those previously found in normal healthy volunteers: the mean peak plasma concentration of remoxipride after 50 mg was 3.3 μmol/l, the mean time to reach this was 2.1 h; the mean area under the plasma concentration/time curve was 27.8 μmol/1.h.1( -1) and the mean elimination half-life of remoxipride was 5.5 h. A significant increase in prolactin levels was detected 2 h after administration of remoxipride but they had reverted to normal 8 h after drug intake in all but one patient. Antipsychotic effects were estimated using the brief psychiatric rating scale (BPRS) and the Krawiecka rating scale (KRS) at admission, baseline (end of the 4 week placebo washout period) and after 7, 14 and 28 days treatment. Following an increase in mean psychosis ratings for both positive and negative symptoms during the placebo washout period, these decreased during active treatment and at the end of the study were similar to the scores on admission. Thus the possible efficacy of remoxipride in chronic patients with negative symptoms should be further explored in placebo controlled studies. Remoxipride was well tolerated. Sleep disorders occurred in three patients, extrapyramidal symptoms were not aggravated and no clinically significant effects were observed on the cardiovascular system, in clinical chemistry or haematology.     

Active-specific immunotherapy for melanoma

Twenty-five patients with metastatic melanoma were treated with a therapeutic vaccine ("theraccine") consisting of allogeneic melanoma lysates and a novel adjuvant, DETOX (Ribi ImmunoChem Research, Inc, Hamilton, MT). Each patient received 200 antigenic units (20 x 10(6) tumor cell equivalents) subcutaneously on weeks 1, 2, 3, 4, and 6. Clinical responses included one complete remission, three partial remissions, and a long-term (17-month) stability. Two other patients had mixed responses, with partial remissions of numerous subcutaneous nodules. Sites of responsive disease included primarily the skin, but ileal, breast, and a liver metastasis also responded. Removal of residual lesions in patients with partial remissions, whose other lesions had disappeared during treatment, led to long disease-free survivals. The median duration of remission was 17 months, with four of the five responders alive for at least 24 months after treatment. An increase in precursors of cytolytic T cells (CTLs) correlated with clinical outcome, when complete, partial, and mixed responses and long-term stability were considered. The CTLs recognized melanoma-associated antigens on many cell lines, but not other types of tumor or normal lymphocytes. Skin-test reactivity to melanoma antigens and serum antibodies against the melanoma cells was unrelated to clinical response. Toxicity was minimal, restricted largely to minor soreness at the site of injection. Only five patients, four of whom were treated with repeated courses, developed severe granulomas. These results confirm that active-specific immunization with allogeneic lysates of melanoma administered with the adjuvant DETOX can induce immunity to melanoma, and can induce regressions of disease in a proportion of patients with metastatic disease with little toxicity.     

趋化因子SDF-1β在大肠杆菌中的表达及其纯化

目的　重组人SDF 1 β在大肠杆菌中表达并获得纯化的有生物学活性的SDF 1 β蛋白。 方法　以pET32a( + ) SDF 1为人SDF 1 β克隆基因的表达载体 ,以大肠杆菌AD494(DE3)pLysS为表达菌 ,在IPTG诱导下表达出一个由 2 30个氨基酸残基组成的硫氧还蛋白 (thioredoxin) SDF 1 β的融合蛋白 ( 2 6× 1 0 3)。经细菌裂解、金属离子螯合亲和层析、肠激酶消化以游离SDF 1 β、阳离子交换层析和逆向高效液相层析等步骤纯化目的蛋白。以蛋白印迹、纯化产物的N端氨基酸测序及配体结合试验、微生理监测术鉴定纯化产物的生化性质及生物学活性。结果　在经诱导的发酵菌中融合蛋白占总菌体蛋白的 1 0 %～ 1 5 %。从 1L发酵菌液中可获得高纯度目的蛋白约 40 0 μg。蛋白印迹实验及N端氨基酸测序皆证实纯化终产物为SDF 1 β(由 71个氨基酸残基组成 ,7.8× 1 0 3)。配体结合试验及Cytosensor表明 ,该产物能与CXCR4结合 [Kd =( 1 2 .2 0± 2 .99)nmol L]并引起CXCR4表达细胞的信号传导。结论　采用本方法可获得高表达的 ,高纯度的具有与天然SDF 1 β相似活性的重组人SDF 1 β。     

Sildenafil: from the bench to the bedside

Erectile dysfunction affects a large segment of the male population, and in most cases impaired relaxation of the smooth muscle cells in the corpus cavernosum and the penile arteries is a factor. Sildenafil, a relatively specific vasodilator of the penile circulation, has revolutionized the treatment of impotence. This article describes the biochemistry of erection, outlines the problems that can lead to erectile dysfunction and explains how sildenafil acts to relieve these problems at the cellular and molecular level. Other aspects of therapy, such as potential side effects and absolute and relative contraindications, are also discussed.     

Reconnecting with relational values in highly conflicted separating couples: A narrative therapy-informed relational interviewing teamwork-based supervision approach

This article outlines a new supervision practice of narrative therapy-informed reflecting team-based relational interviewing for a high-conflict stuck case of a separated middle-aged couple. The article demonstrates the supervision method consisting in five parts. First, the supervisor interviews the couples' relationship while the team watches from behind the one-way mirror. Second, the team responds to the interview while the couple and the supervisor witness their conversation. The couple is then invited to respond back to the team. Furthermore, there is a meta-conversation about the supervision in collaboration with the couple. The intervention ends with therapeutic letter writing to the relationship. The couple showed a meaningful shift in their positioning towards a more relational awareness and found valuable ways for continuing their therapy. The theoretical elements of the approach underpinning practice to tackle high conflict are considered through the illustration of the case.     

Inhibition of neutrophil and monocyte recruitment by endogenous and exogenous lipocortin 1

1. The role played by endogenous lipocortin 1 in the anti-migratory action exerted by dexamethasone (Dex) on monocyte recruitment in an in vivo model of acute inflammation was investigated by use of several neutralizing polyclonal antibodies raised against lipocortin 1 or a lipocortin 1-derived N-terminus peptide (peptide Ac2-26). The efficacy of peptide Ac2-26 in inhibiting monocyte and polymorphonuclear leucocyte (PMN) recruitment was also tested.
2. Intraperitoneal (i.p.) injection of zymosan A (1 mg) produced a time-dependent cell accumulation into mouse peritoneal cavities which followed a typical profile of acute inflammation: PMN influx was maximal at 4 h post-zymosan (between 15 and 20×10⁶ cells per mouse), and this was followed by an accumulation of monocytes which peaked at the 24 h time-point (between 10 and 15×10⁶ cells per mouse).
3. Dex administration to mice reduced zymosan-induced 4 h PMN infiltration and 24 h monocyte accumulation with similar efficacy: approximately 50% of inhibition of recruitment of both cell types was achieved at the dose of 30 μg per mouse (∼1 mg kg⁻¹, subcutaneously (s.c.)). Maximal inhibitions of 64% and 67% on PMN and monocyte recruitment, respectively, were measured after a dose of 100 μg per mouse (∼3 mg kg⁻¹, s.c.).
4. Dex (30 μg s.c.) inhibited monocyte (53%) and PMN (69%) accumulation in response to zymosan application in mice which had been treated with a non-immune sheep serum (50 μl s.c.). In contrast, the steroid was no longer active in reducing cell accumulation in mice which had been passively immunized against full length human recombinant lipocortin 1 (serum LCS3), or against lipocortin 1 N-terminus peptide.
5. Treatment of mice with vinblastine (1 mg kg⁻¹, intravenously (i.v.)) produced a remarkable leucopenia as assessed 24 h after administration. This was accompanied by a 60% reduction in 4 h-PMN influx, and by a 27% reduction in 24 h-monocyte accumulation, measured after zymosan administration. The inhibitory effect of Dex on monocyte recruitment was not significantly modified in vinblastine-treated mice, with 36% and 57% of inhibition calculated at the dose of 30 μg Dex, and 70% and 60% of inhibition at 100 μg Dex, in vehicle- and vinblastine-treated mice, respectively.
6. Treatment of mice with peptide Ac2-26 dose-dependently attenuated PMN influx at 4 h post-zymosan with a significant effect at 100 μg per mouse (45% of inhibition, n=9, P<0.05) and a maximal effect of 61% inhibition at the highest dose tested of 200 μg s.c. (n=14, P<0.05). No effect of peptide Ac2-26 (200 μg s.c.) was seen on zymosan-induced 24 h monocyte recruitment. In contrast, administration of 200 μg peptide Ac2-26 every 6 h was effective in reducing the number of monocytes harvested from the inflamed peritoneal cavities at 24 h post-zymosan: 9.40±0.58×10⁶ monocytes per mouse (n=13) and 5.74±0.34 monocytes per mouse (n=14) in vehicle- and peptide Ac2-26-treated mice, respectively (P<0.05).
7. Finally, peptide Ac2-26 produced a concentration-dependent inhibition of the rate of phagocytosis of mouse resident peritoneal macrophages as measured by flow cytometry, with a maximal reduction of 34% at the highest concentration tested of 100 μg ml⁻¹ (n=8 experiments performed in duplicate; P<0.05).
8. In conclusion, this study suggests that in vivo monocyte recruitment during acute inflammation is, at least in part, under the negative modulatory control of endogenous lipocortin 1 (as seen after administration of Dex by using the specific antisera) and exogenous lipocortin 1 mimetics (as observed with peptide Ac2-26). In addition to the neutrophil, we can now propose that the monocyte also can be a target for the in vivo anti-inflammatory action of lipocortin 1.

     

Evidence for a dilator function of 8-iso prostaglandin F2α in rat pulmonary artery

1. 8-Iso prostaglandin F_2α (8-iso PGF_2α) is one of a series of prostanoids formed independently of the cyclo-oxygenase pathway. It has been shown to be upregulated in many conditions of oxidant stress where its formation is induced by free radical-catalysed actions on arachidonic acid. As 8-iso PGF_2α is formed in vivo in diseases in which oxidant stress is high such as septic shock, we have assessed the relative potency and efficacy of this compound in pulmonary arteries from control and lipopolysaccharide (LPS)-treated rats.
2. Several studies have characterized the contractile actions of 8-iso PGF_2α on various smooth muscle preparations, but its potential dilator actions have not been addressed. Thus these studies examined both the contractile and dilator actions of 8-iso PGF_2α in rat pulmonary artery rings. The thromboxane mimetic U46619, PGE₂ sodium nitroprusside (SNP) and acetyl choline (ACh) were used for comparison. Each prostanoid had to be dissolved in ethanol to a maximum concentration of 1×10⁻² M. At high concentrations, ethanol directly contracted pulmonary vessels. We were therefore limited by the actions of the vehicle such that we were unable to add prostanoids at concentrations higher than 1×10⁻⁴ M. In some cases this meant that maximum responses were not achieved and in these cases the E_max and pD₂ values are apparent estimates.
3. The following rank order of potency was obtained from contractile studies; U46619>8-iso PGF_2α>PGE₂, each prostanoid producing concentration-dependent contractions (10⁻¹⁰3×10⁻⁴ M, 10⁻⁹10⁻⁴ M, 10⁻⁸10⁻⁴ M, respectively). As has been shown previously for other smooth muscle preparations, the thromboxane receptor (TP) antagonist ICI 192605, (1×10⁻⁶, 1×10⁻⁵ and 1×10⁻⁴ M), inhibited the contractions of 8-iso PGF_2α in a concentration-dependent fashion.
4. The nitric oxide synthase inhibitor, N^G-nitro-L-arginine methyl ester (L-NAME; 1×10⁻⁴ M), enhanced the contractile function of both 8-iso PGF_2α and PGE₂, but had no effect on that caused by U46619. Similarly, L-NAME inhibited the dilator function of all agents tested except the exogenous nitric oxide (NO) donor SNP, indicating that PGE₂ and 8-iso PGF_2α like ACh, act through the release of NO. The specificity of the effects of L-NAME were confirmed in studies with the inactive enantiomer D-NAME (1×10⁻⁴ M), which did not affect the contractile or the dilator actions of 8-iso PGF_2α. Furthermore, ICI 192605 enhanced the dilator actions of 8-iso PGF_2α, suggesting that the dilator component of 8-iso PGF_2α was achieved via activation of a non-TP receptor.
5. Isoprostanes may modulate vascular tone by a direct action on TP receptors to cause contraction and via a distinct receptor leading to the release of NO to cause dilatation.

     

The chemopreventive properties of soy isoflavonoids in animal models of breast cancer

Genistein (5,7,4-trihydroxyisoflavone), one of two major isoflavonoids in soy, has anti-proliferative effects on mitogen-stimulated cell growth of human breast cancer cells in culture and is a candidate for use in the prevention of breast cancer. Soy protein preparations containing isoflavonoid conjugates have chemopreventive activity in carcinogen-induced rat models of breast cancer. Recent experiments in these models with purified genistein have revealed that the timing of the exposure of rats to this isoflavonoid is critical. Rats treated neonatally or prepuberally with genistein have a longer latency before the appearance of 7,12-dimethylbenz[a]anthracene-induced mammary tumors and a marked reduction in tumor number. The mechanism of genistein's preventive action is in part dependent on its estrogenic activity, which causes a more rapid differentiation of the cells of the mammary gland, analogous to the effects of an early pregnancy. Rats administered genistein after 35 days of age have smaller alterations in breast cancer risk, with a maximum reduction in mammary tumor number of 27%. In ovariectomized nude mice, dietary genistein increases cell proliferation of human breast cancer MCF-7 cell xenografts compared with a control diet. This estrogen-like effect of genistein is not observed in non-ovariectomized rats. Future studies on the anticancer potential of soy isoflavonoids should examine their interaction with other phytochemical components of soybeans and exploit newly developed animal models of breast cancer in which specific genes have been activated or inactivated.