287 research outputs found
Contrasting cellular uptake pathways for chlorido and iodido iminopyridine ruthenium arene anticancer complexes
The pathways involved in cellular uptake and accumulation of iminopyridine complexes of general formula [Ru(η6-p-cymene)(N,N-dimethyl-N′-[(E)-pyridine-2-ylmethylidene]benzene-1,4-diamine)X]PF6 bearing two different halido ligands X = Cl or I, have been explored. The ratio of passive/active cellular accumulation of Ru in A2780 human ovarian cancer cells is compared and contrasted with cisplatin. Also, saturation of cellular uptake, time-dependence of cellular influx/efflux equilibria, together with endocytotic pathways such as caveolae and facilitated diffusion are investigated and discussed. Temperature dependence studies of Ru accumulation in the A2780 cells show that in contrast to cisplatin (CDDP) and chlorido complex 1, which are taken up largely through active transport, the iodido complex 2 enters cells via passive transport. The cellular efflux of Ru is slow (ca. 25% retained after 72 h) and is partially inhibited by verapamil, implicating the P-gp protein in the efflux mechanism. Ouabain inhibition experiments suggest that the cellular uptake of these ruthenium complexes relies at least in part on facilitated diffusion, and in particular is dependent on the membrane potential. In addition the finding that depletion of cellular ATP with antimycin A had little effect on cellular Ru accumulation from iodido complex 2 is consistent with passive diffusion. In contrast, ATP depletion caused a major increase in cellular accumulation of ruthenium from chlorido complex 1
Proteasome inhibition for treatment of leishmaniasis, Chagas disease and sleeping sickness
Chagas disease, leishmaniasis and sleeping sickness affect 20 million people worldwide and lead to more than 50,000 deaths annually. The diseases are caused by infection with the kinetoplastid parasites Trypanosoma cruzi, Leishmania spp. and Trypanosoma brucei spp., respectively. These parasites have similar biology and genomic sequence, suggesting that all three diseases could be cured with drugs that modulate the activity of a conserved parasite target. However, no such molecular targets or broad spectrum drugs have been identified to date. Here we describe a selective inhibitor of the kinetoplastid proteasome (GNF6702) with unprecedented in vivo efficacy, which cleared parasites from mice in all three models of infection. GNF6702 inhibits the kinetoplastid proteasome through a non-competitive mechanism, does not inhibit the mammalian proteasome or growth of mammalian cells, and is well-tolerated in mice. Our data provide genetic and chemical validation of the parasite proteasome as a promising therapeutic target for treatment of kinetoplastid infections, and underscore the possibility of developing a single class of drugs for these neglected diseases
Characterization of the binding sites of the anticancer ruthenium(III) complexes KP1019 and KP1339 on human serum albumin via competition studies
Indazolium trans-[tetrachloridobis(1H-indazole)ruthenate(III)] (KP1019) and its Na+ analogue (KP1339) are two of the most prominent non-platinum antitumor metal complexes currently undergoing clinical trials. After intravenous administration, they are known to bind to human serum albumin (HSA) in a noncovalent manner. To elucidate their HSA binding sites, displacement reactions with the established site markers warfarin and dansylglycine as well as bilirubin were monitored by spectrofluorimetry, ultrafiltration-UV-vis spectrophotometry, and/or capillary zone electrophoresis. Conditional stability constants for the binding of KP1019 and KP1339 to sites I and II of HSA were determined, indicating that both Ru(III) compounds bind to both sites with moderately strong affinity (log K (1)' = 5.3-5.8). No preference for either binding site was found, and similar results were obtained for both metal complexes, demonstrating low influence of the counter ion on the binding event
The association between misperceptions around weight status and quality of life in adults in Australia
Objective: Limited evidence supports a possible association between a person’s perception of their weight status and their quality of life (QoL). This study evaluates whether misperception around weight status is associated with QoL and the impact of gender on this association. Methods: A cross-sectional survey of Australian adults (n=1,905 analysed) collected selfreported height and weight (used to estimate BMI), gender and QoL (described using the AQoL-8D). Participants reported whether they perceived their weight status to be ‘underweight’, ‘healthy weight’, ‘overweight’ or ‘obese’. Misperception around weight status was categorised based on perceived weight status and self-reported BMI. Ordinary least squares regression was used to test associations between self-reported overall, physical and psychosocial QoL, misperception of weight status, and gender, across different BMI categories, after controlling for income, education, relationship status and health conditions. Results: Compared to accurate perception, underestimation of weight status was associated with higher overall QoL for obese males and females and for overweight males. Overestimation of weight status was associated with higher overall QoL for underweight females and lower overall QoL for healthy weight males and females. The same pattern was seen for psychosocial QoL. Physical QoL was less sensitive to misperception than psychosocial QoL. Conclusions: Self-reported misperception around weight status is associated with overall, psychosocial and to a lesser extent physical QoL in Australian adults, although its role depends on BMI category and gender. Generally misperception in the direction of “healthy weight” is associated with higher QoL and overestimation of weight status by those who are of healthy weight is associated with lower QoL. Findings should be confirmed in datasets that contain measured as opposed to self-report height and weight
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
Electrocautery smoke exposure and efficacy of smoke evacuation systems in minimally invasive and open surgery: a prospective randomized study.
Worldwide, health care professionals working in operating rooms (ORs) are exposed to electrocautery smoke on a daily basis. Aims of this study were to determine composition and concentrations of electrocautery smoke in the OR using mass spectrometry. Prospective observational study at a tertiary care academic center, involving 122 surgical procedures of which 84 were 1:1 computer randomized to smoke evacuation system (SES) versus no SES use. Irritating, toxic, carcinogenic and mutagenic VOCs were observed in OR air, with some exceeding permissible exposure limits (OSHA/NIOSH). Mean total concentration of harmful compounds was 272.69 ppb (± 189 ppb) with a maximum total concentration of harmful substances of 8991 ppb (at surgeon level, no SES). Maximum total VOC concentrations were 1.6 ± 1.2 ppm (minimally-invasive surgery) and 2.1 ± 1.5 ppm (open surgery), and total maximum VOC concentrations were 1.8 ± 1.3 ppm at the OR table 'at surgeon level' and 1.4 ± 1.0 ppm 'in OR room air' away from the operating table. Neither difference was statistically significant. In open surgery, SES significantly reduced maximum concentrations of specific VOCs at surgeon level, including aromatics and aldehydes. Our data indicate relevant exposure of health care professionals to volatile organic compounds in the OR. Surgical technique and distance to cautery devices did not significantly reduce exposure. SES reduced exposure to specific harmful VOC's during open surgery.Trial Registration Number: NCT03924206 (clinicaltrials.gov)
Measuring Health Related Quality of Life for Dengue Patients in Iquitos, Peru
Previous studies measuring the health-related quality of life (HRQoL) of individuals with dengue focused on treatment seeking populations. However, the vast majority of global dengue cases are unlikely to be detected by health systems. Representative measurements of HRQoL should therefore include patients with disease not likely to trigger treatment-seeking behavior. This study based in Iquitos, Peru used the Quality of Wellbeing Scale-Self Administered, a survey that enquires about not only physical health, but also psychological health, self-care, mobility, and usual social activities, and rates HRQoL between 0 (death) and 1 (optimum function), to evaluate the impact of dengue on HRQoL. In order to enroll treatment and non treatment-seeking participants, three modalities of participant recruitment were used. In addition to clinic and community-based febrile surveillance, a contact-cluster methodology was also employed to identify infected individuals less likely to seek treatment. We measured changes in HRQoL and identified common areas of health impairment in 73 virologically confirmed dengue cases at 3 time points during the participant\u27s illness; the early-acute (days 0-6 post symptom onset), late-acute (days 7-20), and convalescent illness phases (days 21 +). Participants reported HRQoL related impairments at significantly higher frequency during the early-acute versus convalescent illness phase (Fisher\u27s exact: P\u3c0.01). There was substantial heterogeneity in scores during each illness phase with median scores in the early-acute, late-acute and convalescent phases of 0.56 (IQR: 0.41-0.64), 0.70 (IQR: 0.57-0.94), and 1 (IQR: 0.80-1.00), respectively. In all illness phases participants recruited in clinics had on average the lowest HRQoL scores where as those recruited in the contact clusters had the highest. Only 1 individual who was recruited in the contact-clusters had no reduction in HRQoL score during their illness. These data illustrate that dengue should be considered as a disease that may have significant implications for not only physical health but also psychological health and social functioning. The impact of dengue on the HRQoL of non-treatment-seeking individuals, although lower than the impact among treatment-seeking individuals, is not necessarily trivial
A Cost Analysis of a Physical Activity Intervention for Older Adults
We examined the costs of a physical activity (PA) and an educational comparison intervention. 424 older adults at risk for mobility disability were randomly assigned to either condition. The PA program consisted of center-based exercise sessions 3x weekly for 8 weeks, 2x weekly for weeks 9 to 24 and weekly behavioral counseling for 10 weeks. Optional sessions were offered during maintenance weeks (25-52). The comparison intervention consisted of weekly education meetings for 24 weeks, and then monthly for 6 months. Cost analyses were conducted from the payer\u27s perspective, with a 1-year time horizon. Intervention costs were estimated by tracking personnel activities and materials used for each intervention and multiplying by national unit cost averages. The average cost/participant was 175 for the PA and the comparison interventions, respectively. A preliminary cost/effectiveness analysis gauged the cost/disability avoided to be $28,206. Costs for this PA program for older adults are comparable to those of other PA interventions. The results are preliminary and a longer study is required to fully assess the costs and health benefits of these interventions
Reference intervals for the urinary steroid metabolome: The impact of sex, age, day and night time on human adult steroidogenesis.
Urinary steroid metabolomics by GC-MS is an established method in both clinical and research settings to describe steroidogenic disorders. However, population-based reference intervals for adults do not exist.
We measured daytime and night time urinary excretion of 40 steroid metabolites by GC-MS in 1128 adult participants of European ancestry, aged 18 to 90 years, within a large population-based, multicentric, cross-sectional study. Age and sex-related patterns in adjacent daytime and night time urine collections over 24 hours were modelled for each steroid metabolite by multivariable linear mixed regression. We compared our results with those obtained through a systematic literature review on reference intervals of urinary steroid excretion.
Flexible models were created for all urinary steroid metabolites thereby estimating sex- and age-related changes of the urinary steroid metabolome. Most urinary steroid metabolites showed an age-dependence with the exception of 6β-OH-cortisol, 18-OH-cortisol, and β-cortol. Reference intervals for all metabolites excreted during 24 hours were derived from the 2.5th and 97.5th percentile of modelled reference curves. The excretion rate per period of metabolites predominantly derived from the adrenals was mainly higher during the day than at night and the correlation between day and night time metabolite excretion was highly positive for most androgens and moderately positive for glucocorticoids.
This study gives unprecedented new insights into sex- and age-specificity of the human adult steroid metabolome and provides further information on the day/night variation of urinary steroid hormone excretion. The population-based reference ranges for 40 GC-MS-measured metabolites will facilitate the interpretation of steroid profiles in clinical practice
Risk of malnutrition and health-related quality of life in community-living elderly men and women: The Tromsø study
Purpose To explore the association between risk of malnutrition as well as current body mass index (BMI) and health-related quality of life (HRQoL) in elderly men and women from the general population. Methods In a cross-sectional population survey including 1,632 men and 1,654 women aged 65 to 87 years from the municipality of Tromsø, Norway, we assessed HRQoL by using the EuroQol (EQ-5D) instrument in three risk groups of malnutrition and in different categories of BMI. The Malnutrition Universal Screening Tool (‘MUST’) was used to evaluate the risk of malnutrition. Results We found a significant reduction in HRQoL with an increasing risk of malnutrition, and this was more pronounced in men than in women. The relationship between BMI and HRQoL was dome shaped, with the highest score values in the BMI category being 25–27.5 kg/m2. Conclusions HRQoL was significantly reduced in elderly men and women at risk of malnutrition. The highest HRQoL was seen in moderately overweight individuals
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