Novel NK1R-Targeted 68Ga-/177Lu-Radioconjugates with Potential Application against Glioblastoma Multiforme: Preliminary Exploration of Structure-Activity Relationships.

Locoregionally administered, NK1 receptor (NK1R) targeted radionuclide therapy is a promising strategy for the treatment of glioblastoma multiforme. So far, the radiopharmaceuticals used in this approach have been based on the endogenous agonist of NK1R, Substance P or on its close analogues. Herein, we used a well-known, small molecular NK1R antagonist, L732,138, as the basis for the radiopharmaceutical vector. First, 14 analogues of this compound were evaluated to check whether extending the parent structure with linkers of different lengths would not deteriorate the NK1R binding. The tested analogues had affinity similar to or better than the parent compound, and none of the linkers had a negative impact on the binding. Next, five DOTA conjugates were synthesized and used for labelling with 68Ga and 177Lu. The obtained radioconjugates turned out to be fairly lipophilic but showed rather limited stability in human plasma. Evaluation of the receptor affinity of the (radio)conjugates showed that neither the chelator nor the metal negatively impacts the NK1R binding. The 177Lu-radioconjugates exhibited the binding characteristics towards NK1R similar or better than that of the 177Lu-labelled derivative of Substance P, which is in current clinical use. The experimental results presented herein, along with their structural rationalization provided by modelling, give insight for the further molecular design of small molecular NK1R-targeting vectors.

Bifunctional Opioid/Melanocortin Peptidomimetics for Use in Neuropathic Pain: Variation in the Type and Length of the Linker Connecting the Two Pharmacophores.

Based on the mechanism of neuropathic pain induction, a new type of bifunctional hybrid peptidomimetics was obtained for potential use in this type of pain. Hybrids consist of two types of pharmacophores that are connected by different types of linkers. The first pharmacophore is an opioid agonist, and the second pharmacophore is an antagonist of the pronociceptive system, i.e., an antagonist of the melanocortin-4 receptor. The results of tests in acute and neuropathic pain models of the obtained compounds have shown that the type of linker used to connect pharmacophores had an effect on antinociceptive activity. Peptidomimetics containing longer flexible linkers were very effective at low doses in the neuropathic pain model. To elucidate the effect of linker lengths, two hybrids showing very high activity and two hybrids with lower activity were further tested for affinity for opioid (mu, delta) and melanocortin-4 receptors. Their complexes with the target receptors were also studied by molecular modelling. Our results do not show a simple relationship between linker length and affinity for particular receptor types but suggest that activity in neuropathic pain is related to a proper balance of receptor affinity rather than maximum binding to any or all of the target receptors.

The solid state VCD of a novel N-acylhydrazone trifluoroacetate.

A novel N-acylhydrazone with pharmaceutical importance was subject of structural and IR/VCD investigations in the solid state. In the crystal structure, dimers of anion-cation pairs are stabilized by H-bonding and ionic interactions. Some less common interaction types, like C=N···C-NH3+ (σ-hole) interactions, hydrazone-aromatic interactions and dispersive contacts of the CF3 groups are also present in the crystal. Satisfactory reproduction of the solid state IR and VCD spectra required that quantum-chemical calculations be done on a tetramer (four cation-anion pairs) cut out from the crystal structure, exhibiting key intermolecular interactions. Ten DFT functionals were assessed as to the agreement between the calculated and experimental spectra. Various approaches to scaling of the calculated frequencies were applied. The best results were yielded with individual (optimized) frequency scaling factors (FSFs) and band half-widths at half maximum-(HWHM) for four separate spectral subregions. The best matching between the experimental and theoretical spectra (according to SimIR, SimVCD and SimVDF indices) was found for the B3PW91 functional, however, a few other functionals follow closely in the ranking. Based on the quantum chemical calculations, spectral assignments have been made.

In Vivo, In Vitro and In Silico Studies of the Hybrid Compound AA3266, an Opioid Agonist/NK1R Antagonist with Selective Cytotoxicity.

AA3266 is a hybrid compound consisting of opioid receptor agonist and neurokinin-1 receptor (NK1R) antagonist pharmacophores. It was designed with the desire to have an analgesic molecule with improved properties and auxiliary anticancer activity. Previously, the compound was found to exhibit high affinity for µ- and δ-opioid receptors, while moderate binding to NK1R. In the presented contribution, we report on a deeper investigation of this hybrid. In vivo, we have established that AA3266 has potent antinociceptive activity in acute pain model, comparable to that of morphine. Desirably, with prolonged administration, our hybrid induces less tolerance than morphine does. AA3266, contrary to morphine, does not cause development of constipation, which is one of the main undesirable effects of opioid use. In vitro, we have confirmed relatively strong cytotoxic activity on a few selected cancer cell lines, similar to or greater than that of a reference NK1R antagonist, aprepitant. Importantly, our compound affects normal cells to smaller extent what makes our compound more selective against cancer cells. In silico methods, including molecular docking, molecular dynamics simulations and fragment molecular orbital calculations, have been used to investigate the interactions of AA3266 with MOR and NK1R. Insights from these will guide structural optimization of opioid/antitachykinin hybrid compounds.

Biochemical and morphological changes in mouse liver induced by mistletoe toxins.

Natural compounds are often characterized by high biological activity and sometimes toxicity. This also applies to compounds contained in the herb mistletoe. The objective of this study was to investigate short-term effects (up to 48 h) of mistletoe toxins on mouse hepatocytes. Standardized mistletoe extract Iscador P was given to female mice as a single injection (0.1 mg/kg b.w., 1 mg/kg b.w., or 2 mg/kg b.w). Activities of lysosomal hydrolases: acid phosphatase, cathepsins D and L, N-acetyl-ß-D-hexosaminidase, ß-D-glucuronidase, ß-D-glucosidase and cytosolic proteases: arginine and leucine aminopeptidases were analyzed in the liver fractions 24 and 48 h after the injection. The morphology of hepatocytes was examined by light and transmission electron microscopy. Iscador P caused a decrease in the activity of all lysosomal hydrolases (except cathepsins) in the lysosomal pellet, and an increase in the activity of both aminopeptidases and ß-D-glucuronidase in the cytosol. However, despite membranotropic properties of the viscotoxins, we did not find a significant labilising effect on the lysosomal membranes. Only ß-D-glucuronidase activity was relocated to the supernatant of lysosomal fraction. Microscopic examinations revealed that hepatocyte mitochondria were enlarged and increased in number, whereas the surface of the rough endoplasmic reticulum was decreased significantly.

UNUSUALLY STABLE ADDUCT BETWEEN METHANOLYZED AMOXICILLIN OR AMPICILLIN AND THEIR DIKETOPIPERAZINE DERIVATIVES.

Amoxicillin and ampicillin were subjected to methanolysis. As expected, the methanolysis products were observed by HPLC-ESI-MS. Besides these products, diketopiperazine derivatives were also detected. Additionally, unusually stable adduct formed between the products of methanolysis and diketopiperazine derivatives was also identified. Analogical adducts were detected when ethanolysis was performed instead of methanolysis. HPLC-ESI-MS analysis of the separated adducts confirmed that the adducts were composed of methanolysis products and diketopiperazine derivatives.

[Attitude of pregnant women towards labour--study of forms of preparation and preferences]. / Postawy ciezarnych wobec porodu--analiza form przygotowania i preferencji.

OBJECTIVE: The aim of this study was to assess the knowledge of alternative delivery techniques among pregnant women and their preferences concerning the course of labour. MATERIAL AND METHODS: 275 woman hospitalizated in obstetric wards in Puck and Ist Clinic in Warsaw were questionnaired in the period of July 2003 - February 2004. The mean age of women was 26 +/- 4.9. 55.7% of them were nulliparous, 44.3% multiparous. T-Student test was used for statistical analysis. RESULTS: The majority of questionnaired women knew alternative positions during delivery and possible analgetic techniques. 25.1% of women attended labour school. 81.2% wanted to give birth in the hospital, 10% at home and 8.8% in the delivery room. 51.1% preferred waterbirth and 22.5% obstetric chair--most of them came from the big cities, were better educated and attended labour school. Almost half of all women are in favour of epidural anaesthesia of delivery. Caesarean section on request was supported by 13.8%. For 67.4% the presence of intimates during labour was important. CONCLUSIONS: Labour school has a significant influence on women's knowledge and their preferences. Waterbirth and other modern delivery techniques are very popular among better educated women from big cities, while those with lower education from small cities and villages prefer "classic" labour. Therefore promotion of modern delivery methods and active participation in labour should be concentrated on these groups of women. Nowadays obstetric departments should ensure not only safety of giving birth but also complete personal comfort for pregnant women.

[Comparison of indications for cesarean section in 1985-86 and 2000-01. Analysis of changes]. / Porównanie wskazan do cicia cesarskiego w latach 1985-86 1 2000-01. Analiza zachodzacych zmian.

UNLABELLED: The aim of this research was a retrospective analysis of indications for caesarean section during last fifteen years and assessing recent trends. MATERIALS AND METHOD: 1106 pregnancies and deliveries by caesarean section at the Ist Clinic of Obstetrics and Gynaecology, Medical University of Warsaw in 1985-86 (547--I group) and 2000-01 (559--II group) were enrolled in the study. It was performed in order to estimate and evaluate such factors as age of women, mean duration of pregnancy, indications for caesarean section, complications, and general newborn condition. RESULTS: In 1985-86 and 2000-01 fetal distress was the most frequent indication for delivery via caesarean section (14.35% and 18.57% respectively, p=ns). It was followed by cephalopelvic disproportion (13.99%) and malposition (13.99%) in I group and by pregnant women diseases (14.07%) and malposition (12.45%) in II group. Analysing pathology of the placenta, we established that index of placenta praevia decreased from 2.49% to 0.57% (p < 0.01) and index of abruption of placenta from 2.25% to 0.81% (p = 0.05). Ratio of cases of cephalopelvic disproportion decreased statistically from 13.99% in the I group to 8.76% in the II group (p = 0.006). Index of prolonged labor in the I stage increased from 8.3% to 12.34% (p = 0.027). CONCLUSIONS: (1) Caesarean section is the surgical method of delivery for women with high risk pregnancy and complicated labor to protect mother and the foetus from the anticipated complications of delivery through natural passages. (2) The overall rate of caesarean section has risen because of widening of the indications. (3) Fetal distress has been the most frequent indication for caesarean section in last fifteen years. (4) Index of indications for cesarean section other than obstetric--ophthalmic, cardiological, neurological and orthopaedic, increased as a result of better health care of pregnant women. (5) Decision to perform caesarean section should be taken in consideration of present clinical situation and future consequences of abdominal delivery.