Prediction of Response to Systemic Corticosteroids in Active UC by Microbial Composition-A Prospective Multicenter Study

BACKGROUND

Corticosteroids are used for induction of remission in patients with moderately to severely active ulcerative colitis. However, up to one-third of patients fail to this therapy. We investigated if fecal microbial composition or its metabolic capacity are associated with response to systemic corticosteroids.

METHODS

In this prospective, multicenter study, patients with active ulcerative colitis (Lichtiger score ≥4) receiving systemic corticosteroids were eligible. Data were assessed and fecal samples collected before and after 4 weeks of treatment. Patients were divided into responders (decrease of Lichtiger Score ≥50%) and nonresponders. The fecal microbiome was assessed by the 16S rRNA gene marker and analyzed with QIIME 2. Microbial metabolic pathways were predicted using parsimonious flux balance analysis.

RESULTS

Among 93 included patients, 69 (74%) patients responded to corticosteroids after 4 weeks. At baseline, responders could not be distinguished from nonresponders by microbial diversity and composition, except for a subgroup of biologic-naïve patients. Within 4 weeks of treatment, responders experienced changes in beta diversity with enrichment of ascribed beneficial taxa, including Blautia, Anaerostipes, and Bifidobacterium, as well as an increase in predicted butyrate synthesis. Nonresponders had only minor longitudinal taxonomic changes with a significant increase of Streptococcus salivarius and a microbial composition shifting away from responders.

CONCLUSION

Baseline microbial diversity and composition seem to be of limited use to predict response to systemic corticosteroids in active ulcerative colitis. Response is longitudinally associated with restoration of microbial composition and its metabolic capacity.

Factors Associated with Response to Systemic Corticosteroids in Active Ulcerative Colitis: Results from a Prospective, Multicenter Trial

BACKGROUND

Among patients with ulcerative colitis, 30-50% receive corticosteroids within the first five years after diagnosis. We aimed to reconsider their effectiveness in the context of the biologic era.

METHODS

In this prospective, multicenter study, patients with active ulcerative colitis (Lichtiger score ≥ 4) were eligible if initiating systemic corticosteroids. The primary endpoint was clinical response (decrease in the Lichtiger score of ≥50%) at week 4. Secondary endpoints included combined response defined as clinical response and any reduction in elevated biomarkers (CRP and/or calprotectin). Steroid dependence was assessed after three months.

RESULTS

A total of 103 patients were included. Clinical response was achieved by 73% of patients, and combined response by 68%. A total of 15% of patients were steroid-dependent. Activity of colitis did not influence short-term response to treatment but increased the risk for steroid dependence. Biologic-naïve patients responded better than biologic-experienced patients. Past smoking history (OR 5.38 [1.71, 20.1], p = 0.003), hemoglobin levels (OR 0.76 [0.57, 0.99] for higher levels, p = 0.045), and biologic experience (OR 3.30 [1.08, 10.6], p = 0.036) were independently associated with nonresponse.

CONCLUSION

Disease activity was not associated with short-term response to systemic corticosteroids but was associated with steroid dependence in patients with active ulcerative colitis. Exposure to biologics negatively affects response rates.

Hematopoietic Stem Cell Transplantation in Refractory Crohn's Disease: Should It Be Considered?

Hematopoietic stem cell transplantation (HSCT) is widely used in benign and malignant hematological diseases. During the last decade, HSCT, mainly autologous, also gained increasing attention in the treatment of refractory autoimmune diseases. Crohn's disease (CD) is an inflammatory bowel disease leading to transmural inflammation potentially affecting all parts of the luminal gastrointestinal tract. Despite improving therapeutic options, including various biologics, some patients are refractory to all lines of available conservative therapy, leading to increased morbidity and reduced quality of life. Apart from surgery, HSCT might be a reasonable treatment alternative for refractory CD patients. This review aims to describe the current role of HSCT in CD and discusses the procedure, the correct patient selection, the clinical efficacy from initial remission to following relapse rates, and complications of this treatment.

Treatment persistence of ustekinumab and vedolizumab in IBD patients is independent of prior immunogenicity to anti-TNFs: a retrospective study

BACKGROUND AND AIMS

Immunological treatment failure of anti-TNF therapy negatively influences treatment persistence of a second anti-TNF in IBD patients. So far it is unknown if this effect is also observed for other monoclonal antibodies. We assessed the influence of immunogenicity to anti-TNFs on treatment persistence of subsequent ustekinumab and vedolizumab therapy.

METHODS

IBD patients with and without immunogenicity to anti-TNFs (undetectable trough levels and antibody titers ≥20 ng/mL) and subsequent ustekinumab (UST) and/or vedolizumab (VDZ) therapy were included in this retrospective, single-center study. The Kaplan-Meier method with the log-rank test and Cox proportional hazards were used as statistical methods.

RESULTS

One hundred patients (Crohn's disease: 62, Ulcerative colitis: 31, IBD unclassified: 7) with 127 treatment lines (62 with UST, 65 with VDZ) were included in the analysis. Immunogenicity to previous anti-TNFs did not influence treatment persistence of subsequent ustekinumab and vedolizumab therapy (UST: Log rank: p = .95, Immunogenicity: HR for treatment discontinuation: 0.97 [95% CI 0.31-3.04]; VDZ: p = .65, HR: 0.85 [0.41-1.75]; total cohort [UST and VDZ]: p = .62, HR: 0.86 [0.47-1.57]). Azathioprine co-treatment did not lengthen treatment persistence (UST: Log rank: p = .77, azathioprine: HR: 1.20 [0.34-4.27]; VDZ: p = .92, HR: 0.58 [0.17-1.99]; total cohort: p = .79, HR: 1.10 [0.55-2.20]). In this anti-TNF experienced cohort, patients with ustekinumab remained longer on treatment than patients receiving vedolizumab (Log rank: p = .005, UST: HR: 0.43 [0.23-0.79]).

CONCLUSIONS

Immunogenicity to anti-TNFs does not influence treatment persistence of subsequent ustekinumab and vedolizumab therapy.

Mixed lymphocytic and collagenous inflammation of the entire gastrointestinal tract under therapy with serotonin and norepinephrine reuptake inhibitors

Drug-induced injury to the gastrointestinal tract has gained growing significance in recent years, and the list of causative medications keeps expanding. Herein, we present the case of a 45-year-old female with major depressive disorder treated with two serotonin and norepinephrine reuptake inhibitors (venlafaxine and duloxetine). She developed nausea and weight loss. Endoscopic evaluation of the upper and lower gastrointestinal tract rendered grossly normal mucosa in all segments. Histological examination, however, revealed lymphocytic esophagitis, collagenous gastritis, celiac disease-like intraepithelial lymphocytosis of the duodenum, and incomplete collagenous colitis. Gastrointestinal side effects of psychoactive drugs are largely underrecognized. This is the first report of a mixed lymphocytic and collagenous pattern of injury affecting esophagus, stomach, duodenum, and colon triggered by combined treatment with venlafaxine and duloxetine. In patients with unclear symptoms, obtaining biopsies from mucosa that is normal upon endoscopic inspection may render decisive clues for clinical management.

Risks in Management of Enteral Nutrition in Intensive Care Units: A Literature Review and Narrative Synthesis

Critically ill patients in the intensive care unit (ICU) have a high risk of developing malnutrition, and this is associated with poorer clinical outcomes. In clinical practice, nutrition, including enteral nutrition (EN), is often not prioritized. Resulting from this, risks and safety issues for patients and healthcare professionals can emerge. The aim of this literature review, inspired by the Rapid Review Guidebook by Dobbins, 2017, was to identify risks and safety issues for patient safety in the management of EN in critically ill patients in the ICU. Three databases were used to identify studies between 2009 and 2020. We assessed 3495 studies for eligibility and included 62 in our narrative synthesis. Several risks and problems were identified: No use of clinical assessment or screening nutrition assessment, inadequate tube management, missing energy target, missing a nutritionist, bad hygiene and handling, wrong time management and speed, nutritional interruptions, wrong body position, gastrointestinal complication and infections, missing or not using guidelines, understaffing, and lack of education. Raising awareness of these risks is a central aspect in patient safety in ICU. Clinical experts can use a checklist with 12 identified top risks and the recommendations drawn up to carry out their own risk analysis in clinical practice.

T-replete haploidentical allogeneic transplantation using post-transplantation cyclophosphamide in advanced AML and myelodysplastic syndromes

Unmanipulated haploidentical transplantation (Haplo-SCT) using post-transplantation cyclophosphamide (PT-Cy) represents an alternative for patients with high-risk diseases lacking HLA-identical donor. Although it provides low incidences of GVHD, the efficacy of Haplo-SCT is still questioned, especially for patients with myeloid malignancies. Thus, we analyzed 60 consecutive patients with refractory (n=30) or high-risk CR (n=30) AML or myelodysplastic syndromes (MDSs) who underwent PT-Cy Haplo-SCT. The median age was 57 years (22-73 years), hematopoietic cell transplantation comorbidity index was ⩾3 in 38 patients (63%) and Haplo-SCT was the second allogeneic transplantation for 10 patients (17%). Although most of patients received PBSC as graft source (n=48, 80%), we found low incidences of grade 3-4 acute (2%) and severe chronic GVHD (4%). Among patients with high-risk CR diseases, 1-year non-relapse mortality, cumulative incidence of relapse, progression-free and overall survivals were 20%, 32%, 47% and 62%, respectively. In patients with refractory disease, corresponding results were 34%, 35%, 32% and 37%, respectively. We conclude that PT-Cy Haplo-SCT could provide promising anti-leukemic effect even in the setting of very advanced diseases. Thus, it represents a viable alternative for high-risk AML/MDS patients without HLA-identical donor.

Impact of flexible body surface coil and patient table on PET quantification and image quality in integrated PET/MR

AIM

The surface coils of the Biograph mMR integrated PET/MR system were optimised for PET, but are otherwise unaccounted for. The patient table is still more massive than those of PET/CT devices. The goal was to assess those hardware effects on quantification, count statistics, image quality and scan time both with phantoms and in patients and to investigate their clinical relevance.

PATIENTS, MATERIAL, METHODS

PET phantom data were acquired with and without the patient table. Image noise was expressed as relative standard deviation and compared to a state-of-the-art PET/CT scanner. Protocols of the phantom/patient study regarding the surface coils were similar. Thoraces/abdomens of 11 patients were scanned with and without a coil (1 BP, 4 min). Mean uptake and standard deviation in a cubical VOI were derived and expressed as SUV.

RESULTS

The patient table reduced the number of true coincidences (trues) by 19% (PET/MR) and by 11% (PET/CT). The scan duration for the mMR had to be increased by approximately 30% to achieve a noise level comparable to that of the PET/CT. Decreased SUVs with coil observed in the phantom were confirmed by the patient study. By removing the coil, the mean liver SUV increased by (6 ± 2)%. With (+3 ± 14)%, the average change was similar in lesions, but exceeded 20% in almost one fifth of them. The number of trues grew by (6 ± 1)% for the patients and by 7% for the phantom.

CONCLUSION

Due to the additional attenuation caused by MR hardware, PET scan durations would have to be increased compared to current PET/CTs to provide similar image noise levels. The effect of the coils is mostly in the order of statistical fluctuations. In tumour lesions, it is more pronounced and shows a larger variability. Therefore, coils should be included in the attenuation correction to ensure accurate quantification and thus comparability across PET/MR and PET/CT scanners and within patient populations.

Effect of graft source on mismatched unrelated donor hemopoietic stem cell transplantation after reduced intensity conditioning

This retrospective report compared the results of graft source on outcome after allogeneic stem cell transplantation (allo-SCT) in patients with hematologic malignancies receiving a reduced intensity conditioning (RIC) regimen. A total of 152 patients received either a RIC allo-SCT using a 9/10 mismatched unrelated donor (MisMUD, n=42) or a double unrelated umbilical cord blood (dUCB, n=110) graft. With a median follow-up of 30.3 months, the cumulative incidence of non-relapse mortality was 26% in the dUCB group versus 24% in the MisMUD group (P=0.95). Grade 3-4 acute graft-versus-host disease (GVHD) incidence was 19.7% in the dUCB group versus 21.4% in the MisMUD group (P=0.83). The cumulative incidence of extensive chronic GVHD at 2 years was 6.4% in the dUCB group versus 21.4% in the MisMUD group (P=0.02). The Kaplan-Meier estimate of overall survival at 2 years was comparable between both groups (52.3% (95% confidence interval (CI), 42.1-61.5%) in the dUCB group versus 47.9% (95% CI, 31.6-62.4%) in the MisMUD group, P=0.55). Progression-free survival at 2 years was 43.3% (95% CI, 33.7-52.5%) in the dUCB group versus 38.3% (95% CI, 23.2-53.3%) in the MisMUD group (P=0.55). These data suggest that dUCB is a valid alternative graft source with significantly less chronic GVHD compared with MisMUD in the setting of RIC allo-SCT.

TLI in refractory chronic GVHD

Refractory chronic GVHD (cGVHD) remains a major cause of morbidity after transplantation. Many drugs are used but there is no consensus on the standard of care. We investigated the efficacy of TLI in corticosteroid-refractory cGVHD. We analyzed retrospectively 31 patients receiving one or more TLI session for refractory cGVHD from 2000 to 2007. The main objective was to evaluate the response rate after TLI. Decreased corticosteroid doses and/or discontinued immunosuppressive agents were considered to be surrogate markers of response. All but one patient presented with severe cGVHD at the time of TLI. The median number of previous immunosuppressive treatment lines was 3 (range: 2-4). Fourteen patients (45%) achieved an objective response after TLI and 8 (25%) were cGVHD free at long-term follow-up. In all, 5 (29%) of the 17 nonresponsive patients did not show the features of progressive cGVHD and could decrease the amount of immunosuppressive drugs taken. Response after TLI significantly improved 5-year GVHD-related mortality (14% vs 42%, P=0.038) but not OS (58%vs 64% P=0.27). Regarding the promising response rate in this heavily pretreated population, we reasoned that TLI could be an alternative treatment for corticosteroid-refractory cGVHD.

Spinal interaction between the highly selective μ agonist DAMGO and several δ opioid receptor ligands in naive and morphine-tolerant mice

Since the discovery of opioid receptor dimers their possible roles in opioid actions were intensively investigated. Here we suggest a mechanism that may involve the μ-δ opioid heterodimers. The exact role of δ opioid receptors in antinociception and in the development of opioid tolerance is still unclear. While receptor up-regulation can be observed during the development of opioid tolerance no μ receptor down-regulation could be detected within five days. In our present work we investigated how the selective δ opioid receptor agonists and antagonists influence the antinociceptive effect of the selective μ receptor agonist DAMGO in naïve and morphine-tolerant mice. We treated male NMRI mice with 200 μmol/kg subcutaneous (s.c.) morphine twice daily for three days. On the fourth day we measured the antinociceptive effect of DAMGO alone and combined with delta ligands: DPDPE, deltorphin II (agonists), TIPP and TICPψ (antagonists), respectively, administered intrathecally (i.t.) in mouse tail-flick test. In naive control mice none of the δ ligands caused significant changes in the antinociceptive action of DAMGO. The treatment with s.c. morphine resulted in approximately four-fold tolerance to i.t. DAMGO, i.e. the ED₅₀ value of DAMGO was four times as high as in naive mice. 500 and 1000 pmol/mouse of the δ₁ selective agonist DPDPE enhanced the tolerance to DAMGO while 1000 pmol/mouse of the δ₂ selective agonist deltorphin II did not influence the degree of tolerance. However, both δ antagonists TIPP and TICPψ potentiated the antinociceptive effect of i.t. DAMGO, thus they restored the potency of DAMGO to the control level. The inhibitory action of DPDPE against the antinociceptive effect of DAMGO could be antagonized by TIPP and TICPψ. We hypothesize that during the development of morphine tolerance the formation of μδ heterodimers may contribute to the spinal opioid tolerance. δ ligands may affect the dimer formation differently. Those, like DPDPE may facilitate the dimer formation hence inhibit the antinociceptive effect of DAMGO by causing virtual μ receptor down-regulation. Ligands that do not affect the dimer formation do not influence antinociception either but ligands with the presumed capability of disconnecting the dimers may decrease the spinal tolerance to DAMGO.

Tandem autologous-allo-SCT is feasible in patients with high-risk relapsed non-Hodgkin's lymphoma

Allo-SCT is used to exploit GVL effect in high-risk relapsed non-Hodgkin's lymphoma (NHL). Here, we retrospectively analyzed 34 high-risk NHL patients who underwent auto-SCT followed closely by reduced-intensity allo-SCT ('tandem auto-allo') from January 2002 to November 2010. The search for an allogeneic donor was started at the beginning of salvage regimen. Median patients' age was 47 (27-68) years; histotypes were: diffuse large B-cell n=5, follicular n=14, transformed follicular n=4, mantle-cell n=5, plasmocytoid lymphoma n=1, anaplastic large T-cell n=2, peripheral T-cell n=3. Donors were HLA-identical siblings (n=29) or 10/10-matched unrelated individuals (n=5). Median interval between auto-SCT and allo-SCT was 77 days (36-197). At a median follow-up of 46 (8-108) months since allo-SCT, 5-year OS is 77% (61-93) and PFS is 68% (51-85). Disease relapse or progression occurred in six patients, 100-day TRM was 0%, 2-year TRM incidence was 6%. In conclusion, tandem transplantation is feasible in high-risk NHL patients having a HLA-identical donor. This approach could represent a suitable therapeutic option for those patients with high-risk NHL potentially benefitting from further therapy after auto-SCT. Donor searches should be started promptly whenever such an approach is chosen.

Relative contributions of peripheral versus supraspinal or spinal opioid receptors to the antinociception of systemic opioids

The contribution of supraspinal, spinal or peripheral mu-opioid receptors (MORs) to the overall antinociception of systemic centrally penetrating versus peripherally restricted opioids has not been thoroughly investigated. Therefore, we examined paw pressure thresholds in Wistar rats with complete Freund's adjuvant hindpaw inflammation following different doses of intraplantar (i.pl.) as well as intravenous (i.v.) fentanyl (6.25-50 μg/kg), morphine (1-7.5 mg/kg) or loperamide (1-7.5 mg/kg). Antagonism of the i.v. mu-opioid agonists by intracerebroventricular (i.c.v.), intrathecal (i.t.) or i.pl. naloxone-methiodide (NLXM) revealed the relative contributions of supraspinal, spinal and peripheral MOR to the overall antinociceptive effects. In parallel, the MOR density at these three levels of pain transmission was assessed by radioligand binding. Antinociceptive effects of i.v. fentanyl and morphine, but not of the peripherally restricted loperamide were two- to threefold greater and longer lasting compared with their i.pl. administration. I.c.v. but not i.pl. NLXM significantly antagonized fentanyl's and morphine's antinociception by 70-80%, whereas i.t. NLXM reduced it by 20-30%. In contrast, antinociception of i.v. loperamide was abolished by i.pl. but not by i.c.v. or i.t. NLXM. In parallel, a respective 32- and sixfold higher MOR density in supraspinal and spinal versus peripheral sensory neurons was detected. In conclusion, in comparison with supraspinal and spinal opioid receptors, peripheral opioid receptors do not significantly contribute to the antinociception of systemic fentanyl and morphine during inflammatory pain. Antinociception of their i.v. administration was superior over both i.v and i.pl. loperamide, acting exclusively via peripheral MOR. These findings may guide the future development of novel peripherally restricted opioids.

[Psychotic and non-psychotic denial of pregnancy]

We report about two patients with denial of pregnancy. While the first patient was free of psychopathological symptoms besides denial of pregnancy until rupture of the membranes, and was able to accomodate the new born, the second patient with psychotic denial of pregnancy could not accomodate the child because of the schizophrenia, so that an adoption was necessary. On the basis of the two cases aetiological, epidemiological, clinical und prognostic implications of psychotic and non-psychotic denial of pregnancy are discussed.

The chemical and pharmacological importance of morphine analogues

The object of this review is to summarize the efforts which resulted in the discovery of therapeutically useful morphine-like drugs. The search for new analgesics can be divided into three stages: (a) search for analgesics with high efficacy and reduced unwanted side-effects; (b) understanding of structure-activity relationships; (c) studies on the mechanism of pain perception and its alleviation by investigation of the pharmacology of opioids. An immense body of literature has been produced on the syntheses of thousands of new compounds which resulted in the development of detailed structure-activity relationships. The physical and psychologic dependence of opioid analgesics also facilitated investigators to solve the problem of the separation of strong analgesia from addiction liability. In the past decades more mixed agonist-antagonist analgesics, pure antagonists devoid of agonist action and potent opioids like the 6,14-ethenomorphinan derivatives were developed. Naloxone, Naltrexone, Buprenorphine and Pentazocine are the outstanding representatives which are introduced into clinical therapy.

Purine Ionotropic (P2X) Receptors

Purinergic signaling is involved in the proper functioning of virtually all organs of the body. Although in some cases purines have a major influence on physiological functions (e.g. thrombocyte aggregation), more often they are just background modulators contributing to fine tuning of biological events. However, under pathological conditions, when a huge amount of adenosine 5'-triphosphate (ATP) can reach the extracellular space, their significance is increasing. ATP and its various degradation products activate membrane receptors divided into two main classes: the metabotropic P2Y and the ionotropic P2X family. This latter group, the purine ionotropic receptor, is the object of this review. After providing a description about the distribution and functional properties of P2X receptors in the body, their pharmacology will be summarized. In the second part of this review, the role of purines in those organ systems and body functions will be highlighted, where the (patho)physiological role of P2X receptors has been suggested or is even well established. Besides the regulation of organ systems, for instance in the cardiovascular, respiratory, genitourinary or gastrointestinal system, some special issues will also be discussed, such as the role of P2X receptors in pain, tumors, central nervous system (CNS) injury and embryonic development. Several examples will indicate that purine ionotropic receptors might serve as attractive targets for pharmacological interventions in various diseases, and that selective ligands for these receptors will probably constitute important future therapeutic tools in humans.

High-dose weekly liposomal amphotericin B antifungal prophylaxis following reduced-intensity conditioning allogeneic stem cell transplantation

The use of high-dose corticosteroids for graft-versus-host disease (GVHD) treatment represents a major risk factor for long-term invasive fungal infections. The aim of this study was to investigate the safety and tolerance of weekly prophylactic administration of once-weekly high-dose (7.5 mg/kg) of liposomal amphotericin B (L-AmB) therapy in 21 adult patients receiving high-dose prednisone (2 mg/kg/day) for acute GVHD therapy after reduced intensity conditioning (RIC) allogeneic stem cell transplantation (allo-SCT). Patients received a median of 4 (range, 1-8) infusions of L-AmB. Seven patients (33%; 95% confidence intervals (CI), 13-53%) discontinued taking the study drug owing to study drug-related adverse events, including elevated serum creatinine (>1.5 times from baseline values; n=5), hypotension and pain (n=1), and violent chest pain and arrhythmia (n=1). The overall frequency of infusion-related reactions was 29% (n=6; 95% CI, 10-48%), but these reactions were always transient and relieved by stopping the infusion. This safety data provide support for an efficacy study of this prophylaxis strategy, because this may help further improving the outcome of RIC or nonmyeloablative allo-SCT.

Outcome and long-term follow-up of alloreactive donor lymphocyte infusions given for relapse after myeloablative allogeneic hematopoietic stem cell transplantations (HSCT)

In order to study efficacy, toxicity and the long-term results of donor lymphocyte infusions (DLI), we retrospectively analyzed DLI given for relapse after conventional allogeneic hematopoietic stem cell transplantation (HSCT) in 30 patients with a median delay of 107.5 months after transplant and 58 months after DLI. After DLI, 15 patients established full donor chimerism, three patients developed grade III and one grade IV acute GVHD. A total of 15 patients achieved a disease response. Among the 14 patients with chronic myeloid leukemia (CML), 11 are alive at the last follow-up: five are in complete molecular response (CMR) and two in complete cytogenetic response (CCR) with no other intervention after DLI, three in CMR after imatinib mesylate given after DLI and one in complete hematological response after imatinib mesylate and reduced-intensity conditioning allogeneic SCT performed after DLI. At the time of the last follow-up, 19 (63%) patients died and 11 (37%) remain alive. The 3-year probability of survival for the entire population, CML patients and non-CML patients, was 60, 93, 62% after transplantation, and 48, 80 and 48% after DLI, respectively. A multivariate analysis demonstrated a significantly worse survival rate after transplantation for female recipients, advanced disease and acute leukemia before transplantation.

Effects of structural modifications of N-CPM-normorphine derivatives on agonist and antagonist activities in isolated organs

The agonistic and antagonistic properties of N-cyclopropylmethyl (N-CPM) morphine derivatives were observed in mouse vas deferens (MVD), longitudinal muscle of guinea pig ileum (GPI) and rabbit vas deferens (LVD). In MVD the K(e) values of the titled compounds (N-CPM-morphine, N-CPM-isomorphine, N-CPM-dihydromorphine, N-CPM-dihydroisomorpPhine, N-CPM-dihydromorphone and naltrexone) were measured for mu-, kappa- and delta-receptors using normorphine, ethylketocyclazocine (EKC) and D-Pen2-D-Pen5-enkephaline (DPDPE) as selective agonists on the receptors, respectively. For mu-receptors of MVD the tested compounds showed similar affinity. For kappa-receptors the non-iso-6-OH derivatives possessed much less affinity than the iso-derivatives. Similar difference could be observed for delta-receptors. The agonistic activities of these compounds in MVD were observed to be between 0-20% of the inhibition of muscle contractions. In GPI the compounds except naltrexone possessed strong agonistic activities effectively antagonized by nor-binaltorphimine (nor-BNI) (K(e) of nor-BNI was 0.23 nM) suggesting that they were strong kappa-receptor agonists. We investigated these agents in LVD too, which contains kappa-receptors, but they did not produce any agonist potencies. It raises the possibility that the kappa-receptor subtypes of LVD and MVD are different from the kappa-receptor subtype of GPI or the vasa deferentia contain much fewer kappa-receptors than GPI and the intrinsic activities of these compounds are too small to reach the 50% inhibition of the contractions.

Behavioural changes in rats treated with a neurotoxic dose regimen of dextrorotatory amphetamine derivatives

Repeated administration of amphetamine derivatives is reported to induce neurotoxicity in rat brain. Methamphetamine (MA) impairs the function of both the dopaminergic and serotonergic systems, 3,4-methylenedioxymethamphetamine (MDMA, Ecstasy) affects primarily the latter system. The neurochemical deficits induced by these amphetamines have been described in detail, but relatively few data have been reported regarding the behavioural consequences of the neurotoxic treatment. The aim of the present study was to investigate short- and long-term behavioural consequences of treatment with neurotoxic doses of (+)MA or (+)MDMA. Spontaneous locomotor activity in novel surroundings and cognitive function (avoidance behaviour) were evaluated. Rats were treated with four s.c. injections of 10 mg/kg (+)MA or (+)MDMA with a 2-hour interval between each injection. Behavioural tests were then carried out 3 days, 1, 2 and 4 weeks after these treatments. A reduction of spontaneous locomotor activity in novel surroundings was detected 3 days after the treatment with the study drugs, but not after 1, 2 and 4 weeks. No change in passive and active avoidance learning was observed. The lack of marked behavioural changes after a neurotoxic dose regimen indicates that some compensatory mechanisms may develop and counterbalance the neurochemical changes induced by these amphetamine compounds.

Reactions of morphine derivatives with phenyliodo(III)diacetate (PIDA): synthesis of new morphine analogues

The reactions of morphine and its derivatives with phenyliodo(III)diacetate (PIDA) have been studied. This methodology has not been introduced to morphine alkaloids, despite the fact that such a strategy would ensure dearomatization of the electrophilic aromatic ring of morphine derivatives leading to nucleophilic ortho-quinoidal structures with potential pharmacological interest. The products, formed in regio- and diastereoselective or diastereospecific reactions, carry mixed-acetal or 1,3-dioxolane moieties. At low concentrations 6a has mu-opioid agonist character but in higher concentrations showed a non receptorial antagonist effect on isolated mouse vas deferens.