Conjugation of a Ru(II) Arene Complex to Neomycin or to Guanidinoneomycin Leads to Compounds with Differential Cytotoxicities and Accumulation between Cancer and Normal Cells

A straightforward methodology for the synthesis of conjugates between a cytotoxic organometallic ruthenium(II) complex and amino- and guanidinoglycosides, as potential RNA-targeted anticancer compounds, is described. Under microwave irradiation, the imidazole ligand incorporated on the aminoglycoside moiety (neamine or neomycin) was found to replace one triphenylphosphine ligand from the ruthenium precursor [(η6-p-cym)RuCl(PPh3)2]+, allowing the assembly of the target conjugates. The guanidinylated analogue was easily prepared from the neomycin-ruthenium conjugate by reaction with N,N′-di-Boc-N″-triflylguanidine, a powerful guanidinylating reagent that was compatible with the integrity of the metal complex. All conjugates were purified by semipreparative high-performance liquid chromatography (HPLC) and characterized by electrospray ionization (ESI) and matrix-assisted laser desorption-ionization time-of-flight (MALDI-TOF) mass spectrometry (MS) and NMR spectroscopy. The cytotoxicity of the compounds was tested in MCF-7 (breast) and DU-145 (prostate) human cancer cells, as well as in the normal HEK293 (Human Embryonic Kidney) cell line, revealing a dependence on the nature of the glycoside moiety and the type of cell (cancer or healthy). Indeed, the neomycin-ruthenium conjugate (2) displayed moderate antiproliferative activity in both cancer cell lines (IC50 ≈ 80 μM), whereas the neamine conjugate (4) was inactive (IC50 ≈ 200 μM). However, the guanidinylated analogue of the neomycin-ruthenium conjugate (3) required much lower concentrations than the parent conjugate for equal effect (IC50 = 7.17 μM in DU-145 and IC50 = 11.33 μM in MCF-7). Although the same ranking in antiproliferative activity was found in the nontumorigenic cell line (3 2 > 4), IC50 values indicate that aminoglycoside-containing conjugates are about 2-fold more cytotoxic in normal cells (e.g., IC50 = 49.4 μM for 2) than in cancer cells, whereas an opposite tendency was found with the guanidinylated conjugate, since its cytotoxicity in the normal cell line (IC50 = 12.75 μM for 3) was similar or even lower than that found in MCF-7 and DU-145 cancer cell lines, respectively. Cell uptake studies performed by ICP-MS with conjugates 2 and 3 revealed that guanidinylation of the neomycin moiety had a positive effect on accumulation (about 3-fold higher in DU-145 and 4-fold higher in HEK293), which correlates well with the higher antiproliferative activity of 3. Interestingly, despite the slightly higher accumulation in the normal cell than in the cancer cell line (about 1.4-fold), guanidinoneomycin-ruthenium conjugate (3) was more cytotoxic to cancer cells (about 1.8-fold), whereas the opposite tendency applied for neomycin-ruthenium conjugate (2). Such differences in cytotoxic activity and cellular accumulation between cancer and normal cells open the way to the creation of more selective, less toxic anticancer metallodrugs by conjugating cytotoxic metal-based complexes such as ruthenium(II) arene derivatives to guanidinoglycosides

Stimuli of Sensory-Motor Nerves Terminate Arterial Contractile Effects of Endothelin-1 by CGRP and Dissociation of ET-1/ETA-Receptor Complexes

Endothelin-1 (ET-1), a long-acting paracrine mediator, is implicated in cardiovascular diseases but clinical trials with ET-receptor antagonists were not successful in some areas. We tested whether the quasi-irreversible receptor-binding of ET-1 (i) limits reversing effects of the antagonists and (ii) can be selectively dissociated by an endogenous counterbalancing mechanism.-receptor complexes.-receptors by ET-1 (i) occur at an antagonist-insensitive site of the receptor and (ii) are selectively terminated by endogenously released CGRP. Hence, natural stimuli of sensory-motor nerves that stimulate release of endogenous CGRP can be considered for therapy of diseases involving ET-1

Clonal chromosomal mosaicism and loss of chromosome Y in elderly men increase vulnerability for SARS-CoV-2

The pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2, COVID-19) had an estimated overall case fatality ratio of 1.38% (pre-vaccination), being 53% higher in males and increasing exponentially with age. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, we found 133 cases (1.42%) with detectable clonal mosaicism for chromosome alterations (mCA) and 226 males (5.08%) with acquired loss of chromosome Y (LOY). Individuals with clonal mosaic events (mCA and/or LOY) showed a 54% increase in the risk of COVID-19 lethality. LOY is associated with transcriptomic biomarkers of immune dysfunction, pro-coagulation activity and cardiovascular risk. Interferon-induced genes involved in the initial immune response to SARS-CoV-2 are also down-regulated in LOY. Thus, mCA and LOY underlie at least part of the sex-biased severity and mortality of COVID-19 in aging patients. Given its potential therapeutic and prognostic relevance, evaluation of clonal mosaicism should be implemented as biomarker of COVID-19 severity in elderly people. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, individuals with clonal mosaic events (clonal mosaicism for chromosome alterations and/or loss of chromosome Y) showed an increased risk of COVID-19 lethality

Radiation dose reduction in CT-guided sacroiliac joint injections to levels of pulsed fluoroscopy: a comparative study with technical considerations

Juraj Artner, Balkan Cakir, Heiko Reichel, Friederike LattigDepartment of Orthopaedic Surgery, University of Ulm, RKU, GermanyBackground: The sacroiliac (SI) joint is frequently the primary source of low back pain. Over the past decades, a number of different SI injection techniques have been used in its diagnosis and therapy. Despite the concerns regarding exposure to radiation, image-guided injection techniques are the preferred method to achieve safe and precise intra-articular needle placement. The following study presents a comparison of radiation doses, calculated for fluoroscopy and CT-guided SI joint injections in standard and low-dose protocol and presents the technical possibility of CT-guidance with maximum radiation dose reduction to levels of fluoroscopic-guidance for a precise intra-articular injection technique.Objective: To evaluate the possibility of dose reduction in CT-guided sacroiliac joint injections to pulsed-fluoroscopy-guidance levels and to compare the doses of pulsed-fluoroscopy-, CT-guidance, and low-dose CT-guidance for intra-articular SI joint injections.Study design: Comparative study with technical considerations.Methods: A total of 30 CT-guided intra-articular SI joint injections were performed in January 2012 in a developed low-dose mode and the radiation doses were calculated. They were compared to 30 pulsed-fluoroscopy-guided SI joint injections, which were performed in the month before, and to five injections, performed in standard CT-guided biopsy mode for spinal interventions. The statistical significance was calculated with the SPSS software using the Mann–Whitney U-Test. Technical details and anatomical considerations were provided.Results: A significant dose reduction of average 94.01% was achieved using the low-dose protocol for CT-guided SI joint injections. The radiation dose could be approximated to pulsed-fluoroscopy-guidance levels.Conclusion: Radiation dose of CT-guided SI joint injections can be decreased to levels of pulsed fluoroscopy with a precise intra-articular needle placement using the low-dose protocol. The technique is simple to perform, fast, and reproducible.Keywords: sacroiliac joint pain, computed tomography, guided injections, low-dose protocol, sacroiliac joint injection, low back pain, radiation dos

Does the diagnosis influence the outcome in multimodal outpatient pain management program for low back pain and sciatica? a comparative study

Juraj Artner, Stephan Kurz, Balkan Cakir, Heiko Reichel, Friederike LattigDepartment of Orthopaedic Surgery, University of Ulm, GermanyAbstract: The literature describes multimodal pain-management programs as successful therapy options in the conservative treatment of chronic low back pain. Yet, the intensity and inclusion criteria of such programs remain debatable. In many studies, the pain originating from spinal structures is described as nonspecific low back pain – a diffuse diagnosis without serious implications. The purpose of this study is to compare the short-term outcomes between patients suffering from sciatica due to a discus intervertebralis herniation and those suffering from low back pain caused by facet joint disease after 3 weeks of treatment in an intense multimodal outpatient program in the Department of Orthopaedic Surgery at the university hospital.Keywords: chronic low back pain, sciatica, interdisciplinary management, discus herniation, spondylarthriti

Prevalence of sleep deprivation in patients with chronic neck and back pain: a retrospective evaluation of 1016 patients

Juraj Artner.1 Balkan Cakir,1 Jane-Anna Spiekermann,2 Stephan Kurz,1 Frank Leucht,1 Heiko Reichel,1 Friederike Lattig11Department of Orthopedic Surgery, 2Department of Psychosomatic Medicine and Psychotherapy, University of Ulm, Ulm, GermanyBackground: Chronic low back pain (CLBP) and chronic neck pain (CNP) have become a serious medical and socioeconomic problem in recent decades. Patients suffering from chronic pain seem to have a higher prevalence of sleep disorders.Purpose: To calculate the prevalence of sleep deprivation in patients with CLBP and CNP and to evaluate the factors that may contribute to sleep impairment.Methods: This study was a retrospective evaluation of 1016 patients with CNP and CLBP who consulted an orthopedic department at a university hospital. Factors assessed were gender, age, diagnosis, grade of sleep deprivation, pain intensity, chronification grade, and migrational background. Pearson's chi-squared test was performed to calculate the relationship between these factors and the grade of sleep deprivation. Regression analysis was performed to explore the correlation between the grade of sleep deprivation and age, pain intensity, and chronification grade.Results: A high prevalence of sleep deprivation (42.22%) was calculated in patients with CNP and CLBP, even when analgesics had been taken. About 19.88% of the patients reported serious sleep impairments (ie, <4 hours of sleep per night). The grade of sleep deprivation did not correlate with the gender or age distribution. A significant relationship was found between the grade of sleep deprivation and pain intensity, failed back surgery syndrome, and patients with a migrational background. There was a moderate relationship with intervertebral disc disease and no relationship with spinal stenosis.Conclusion: Sleep disturbance should be assessed when treating patients with CNP or CLBP, especially in patients with higher pain intensity, failed back surgery syndrome, and a migrational background. Further research is needed to explore the complex relationship of sleep disturbance and chronic pain.Keywords: sleep disturbance, impairment, chronic low back pain, failed back surgery, disc disease, spinal stenosis, spondylolisthesis, migrational background, prevalenc

Estudios citogenéticos y moleculares en una población sorda institucionalizada con síndrome de waardenburg en colombia

El Síndrome de Waardenburg (WS) es un desorden autosómico dominante caracterizado por sordera neurosensorial y anormalidades pigmentarias en la piel y faneras. Es clínica y genéticamente heterogéneo y ha sido dividido en 4 subtipos. Según la presencia o ausencia de distopia cantorum (desplazamiento lateral del canto interno de los ojos), se subdividen en WS 1 (gen PAX 3) y WS 2 (gen MITF), respectivamente