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1.
Med Mycol ; 62(3)2024 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-38444173

RESUMEN

Limited data on the clinical management of drug-drug interactions between triazoles and Cystic Fibrosis transmembrane conductance regulator (CFTR) modulators are available. We retrospectively evaluated azole target attainment and dose adaptations in patients from two Dutch CF centres concomitantly receiving triazoles and CFTR modulators. In total, 21 patients with 59 triazole trough concentrations were evaluated. Subtherapeutic concentrations were frequently observed, especially for itraconazole and voriconazole. Of the investigated antifungal agents, posaconazole appears the most preferable option. Our results emphasize the importance of adequate management of this interaction and underpin the added value of therapeutic drug monitoring of triazoles in this population.


Fungal infections are serious complications in Cystic Fibrosis (CF) patients. We evaluated patients concomitantly receiving triazoles and CF transmembrane conductance regulator modulators: subtherapeutic triazole exposure was frequently observed. Posaconazole appears the preferable antifungal agent.


Asunto(s)
Regulador de Conductancia de Transmembrana de Fibrosis Quística , Fibrosis Quística , Humanos , Regulador de Conductancia de Transmembrana de Fibrosis Quística/genética , Antifúngicos/farmacología , Antifúngicos/uso terapéutico , Fibrosis Quística/tratamiento farmacológico , Fibrosis Quística/veterinaria , Estudios Retrospectivos , Triazoles/farmacología , Triazoles/uso terapéutico , Mutación
2.
J Cyst Fibros ; 23(3): 549-553, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38290918

RESUMEN

BACKGROUND: The use of elexacaftor/tezacaftor/ivacaftor (ETI) in people with cystic fibrosis (pwCF) after solid organ transplantation is controversial because of potential drug-drug interactions (DDI) with tacrolimus. We aimed to improve insight into the safety and clinical benefits of co-administration of ETI and tacrolimus in liver or kidney transplanted adult pwCF. METHODS: In 5 pwCF, tacrolimus concentrations were monitored during 2 weeks before and 4 weeks after starting ETI treatment. Trough levels, area under the curve (AUC) and clinical effect of ETI were investigated. During the study (6 weeks in total) adverse events were monitored. RESULTS: The DDI between tacrolimus and ETI resulted in an increased exposure of tacrolimus in all subjects, the dose adjusted AUC0-24h was 1.79 (median) times higher at the end of the study. Five dose adjustments were performed in 4 subjects in order to attain tacrolimus target range. No adverse events were reported and all subjects showed clinical improvement during ETI treatment. CONCLUSION: The clinical value of ETI treatment in kidney and liver transplanted pwCF is clear. The use of ETI may increase tacrolimus levels moderately. Therefore, we recommend close monitoring of tacrolimus trough levels in patients who start ETI.


Asunto(s)
Aminofenoles , Benzodioxoles , Fibrosis Quística , Interacciones Farmacológicas , Inmunosupresores , Indoles , Trasplante de Riñón , Trasplante de Hígado , Quinolonas , Tacrolimus , Humanos , Fibrosis Quística/cirugía , Fibrosis Quística/tratamiento farmacológico , Tacrolimus/administración & dosificación , Tacrolimus/farmacocinética , Tacrolimus/efectos adversos , Masculino , Femenino , Adulto , Benzodioxoles/efectos adversos , Benzodioxoles/administración & dosificación , Benzodioxoles/uso terapéutico , Quinolonas/administración & dosificación , Quinolonas/efectos adversos , Quinolonas/farmacocinética , Trasplante de Hígado/métodos , Inmunosupresores/administración & dosificación , Inmunosupresores/efectos adversos , Inmunosupresores/farmacocinética , Trasplante de Riñón/efectos adversos , Aminofenoles/administración & dosificación , Aminofenoles/efectos adversos , Aminofenoles/farmacocinética , Aminofenoles/uso terapéutico , Indoles/administración & dosificación , Indoles/efectos adversos , Indoles/farmacocinética , Pirazoles/farmacocinética , Pirazoles/administración & dosificación , Pirazoles/efectos adversos , Combinación de Medicamentos , Piridinas/administración & dosificación , Piridinas/farmacocinética , Piridinas/efectos adversos , Pirroles/administración & dosificación , Pirroles/farmacocinética , Pirroles/efectos adversos , Quinolinas/administración & dosificación , Quinolinas/efectos adversos , Quinolinas/farmacocinética , Adulto Joven , Monitoreo de Drogas/métodos , Pirrolidinas
3.
J Cyst Fibros ; 22(3): 564-569, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36496343

RESUMEN

BACKGROUND: Cystic fibrosis transmembrane conductance regulator (CFTR) modulator therapies target the underlying cause of cystic fibrosis (CF), and show robust treatment effects at group level. The individual effect however, is variable which might be (partially) related to differences in drug exposure. The profound influence of fat containing food compared to fasting on drug exposure gives need to investigate if the exocrine pancreatic function changes the degree and rate of absorption of ivacaftor and thereby may contribute to differences in drug exposure. METHODS: Pharmacokinetic parameters of ivacaftor were measured in 10 pancreatic sufficient (PS) and 10 pancreatic insufficient (PI) patients with CF on current treatment with tezacaftor/ivacaftor and compared between both groups. In PI patients pharmacokinetic parameters were investigated with and without the use pancreatic enzymes and compared in each individual. RESULTS: We demonstrated that the pharmacokinetic parameters of ivacaftor did not differ significantly between PS and PI people with CF (pwCF). Pancreatic enzymes did not significantly change the absorption or exposure to ivacaftor in PI pwCF using tezacaftor/ivacaftor. CONCLUSION: The exocrine pancreatic function of pwCF does not significantly influence the absorption and exposure of ivacaftor. The use of pancreatic enzymes in PI pwCF does not change the absorption and exposure of ivacaftor. Therefore, the dosing advice as mentioned in the SmPC for ivacaftor can be maintained independent of the exocrine pancreatic function.


Asunto(s)
Fibrosis Quística , Humanos , Fibrosis Quística/complicaciones , Fibrosis Quística/tratamiento farmacológico , Regulador de Conductancia de Transmembrana de Fibrosis Quística , Aminofenoles/uso terapéutico , Mutación
5.
J Med Ethics ; 2021 Mar 09.
Artículo en Inglés | MEDLINE | ID: mdl-33687917

RESUMEN

The COVID-19 pandemic put a large burden on many healthcare systems, causing fears about resource scarcity and triage. Several COVID-19 guidelines included age as an explicit factor and practices of both triage and 'anticipatory triage' likely limited access to hospital care for elderly patients, especially those in care homes. To ensure the legitimacy of triage guidelines, which affect the public, it is important to engage the public's moral intuitions. Our study aimed to explore general public views in the UK on the role of age, and related factors like frailty and quality of life, in triage during the COVID-19 pandemic. We held online deliberative workshops with members of the general public (n=22). Participants were guided through a deliberative process to maximise eliciting informed and considered preferences. Participants generally accepted the need for triage but strongly rejected 'fair innings' and 'life projects' principles as justifications for age-based allocation. They were also wary of the 'maximise life-years' principle, preferring to maximise the number of lives rather than life years saved. Although they did not arrive at a unified recommendation of one principle, a concern for three core principles and values eventually emerged: equality, efficiency and vulnerability. While these remain difficult to fully respect at once, they captured a considered, multifaceted consensus: utilitarian considerations of efficiency should be tempered with a concern for equality and vulnerability. This 'triad' of ethical principles may be a useful structure to guide ethical deliberation as societies negotiate the conflicting ethical demands of triage.

6.
Biochem Pharmacol ; 180: 114141, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32652143

RESUMEN

Over 200 million people worldwide are exposed to the human carcinogen, arsenic, in contaminated drinking water. In laboratory animals, arsenic and the essential trace element, selenium, can undergo mutual detoxification through the formation of the seleno-bis(S-glutathionyl) arsinium ion [(GS)2AsSe]-, which undergoes biliary and fecal elimination. [(GS)2AsSe]-, formed in animal red blood cells (RBCs), sequesters arsenic and selenium, and slows the distribution of both compounds to peripheral tissues susceptible to toxic effects. In human RBCs, the influence of arsenic on selenium accumulation, and vice versa, is largely unknown. The study aims were to characterize arsenite (AsIII) and selenite (SeIV) uptake by human RBCs, to determine if SeIV and AsIII increase the respective accumulation of the other in human RBCs, and ultimately to determine if this occurs through the formation and sequestration of [(GS)2AsSe]-. 75SeIV accumulation was temperature and Cl--dependent, inhibited by 4,4'-diisothiocyanatodihydrostilbene-2,2'-disulfonic acid (H2DIDS) (IC50 1 ± 0.2 µM), and approached saturation at 30 µM, suggesting uptake is mediated by the erythrocyte anion-exchanger 1 (AE1 or Band 3, gene SLC4A1). HEK293 cells overexpressing AE1 showed concentration-dependent 75SeIV uptake. 73AsIII uptake by human RBCs was temperature-dependent, partly reduced by aquaglyceroporin 3 inhibitors, and not saturated. AsIII increased 75SeIV accumulation (in the presence of albumin) and SeIV increased 73AsIII accumulation in human RBCs. Near-edge X-ray absorption spectroscopy revealed the formation of [(GS)2AsSe]- in human RBCs exposed to both AsIII and SeIV. The sequestration of [(GS)2AsSe]- in human RBCs potentially slows arsenic distribution to susceptible tissues and could reduce arsenic-induced disease.


Asunto(s)
Arsenitos/sangre , Eritrocitos/metabolismo , Glutatión/sangre , Ácido Selenioso/sangre , Arsenitos/farmacología , Transporte Biológico/efectos de los fármacos , Transporte Biológico/fisiología , Relación Dosis-Respuesta a Droga , Eritrocitos/efectos de los fármacos , Células HEK293 , Humanos , Ácido Selenioso/farmacología , Espectroscopía de Absorción de Rayos X/métodos
7.
Acad Pediatr ; 20(2): 225-233, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31541703

RESUMEN

OBJECTIVE: Among US-born children of Latina US (USB) and Latina foreign-born mothers (FBM), to determine whether 1) household and child characteristics differ; 2) child health outcomes differ; 3) these differences diminish for children of FBM with longer duration of residence in the United States; and 4) these differences can be explained by food insecurity (FI) or by Supplemental Nutrition Assistance Program (SNAP) participation. METHODS: Cross-sectional survey of 2145 Latina mothers of publicly insured US-born children 0 to 48 months old in a Boston emergency department (ED) 2004 to 2013. Predictors were FBM versus USBM and duration of residence in the United States. Outcomes were mothers' report of child health, history of hospitalization, developmental risk, and hospital admission on the day of ED visit. Multivariable logistic regression adjusted for potential confounders and effect modification. RESULTS: FBM versus USBM households had more household (31% vs 26%) and child (19% vs 11%) FI and lower SNAP participation (44% vs 67%). Children of FBM versus USBM were more likely to be reported in fair/poor versus good/excellent health (adjusted odds ratios 1.9, 95% confidence interval [1.4, 2.6]), with highest odds for children of FBM with shortest duration of residence, and to be admitted to the hospital on the day of the ED visit (adjusted odds ratios 1.7, 95% confidence interval [1.3, 2.2]). SNAP and FI did not fully explain these outcomes. CONCLUSION: When providing care and creating public policies, clinicians and policymakers should consider higher rates of food insecurity, lower SNAP participation, and risk for poor health outcomes in Latinx children of FBM.


Asunto(s)
Salud Infantil , Emigrantes e Inmigrantes/estadística & datos numéricos , Asistencia Alimentaria/estadística & datos numéricos , Inseguridad Alimentaria , Hispánicos o Latinos/estadística & datos numéricos , Madres/estadística & datos numéricos , Adulto , Boston/epidemiología , Estudios de Casos y Controles , Preescolar , Discapacidades del Desarrollo/epidemiología , República Dominicana/etnología , El Salvador/etnología , Servicio de Urgencia en Hospital , Femenino , Hospitalización/estadística & datos numéricos , Humanos , Lactante , Recién Nacido , América Latina/etnología , Modelos Logísticos , Masculino , Puerto Rico/etnología , Factores Socioeconómicos , Factores de Tiempo , Estados Unidos/epidemiología , Adulto Joven
8.
J Inorg Biochem ; 199: 110781, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31357067

RESUMEN

Recently, 3-dimensional supramolecular coordination complexes of the metallacage type have been shown to hold promise as drug delivery systems for different cytotoxic agents, including the anticancer drug cisplatin. However, so far only limited information is available on their uptake and sub-cellular localisation in cancer cells. With the aim of understanding the fate of metallacages in cells by fluorescence microscopy, three fluorescent Pd2L4 metallacages were designed and synthesised by self-assembly of two types of bispyridyl ligands (L), exo-functionalised with boron dipyrromethene (BODIPY) moieties, with Pd(II) ions. The cages show high quantum yields and are moderately stable in the presence of physiologically relevant concentration of glutathione. Furthermore, the cages are able to encapsulate the anticancer drug cisplatin, as demonstrated by NMR spectroscopy. Preliminary cytotoxicity studies in a small panel of human cancer cells showed that the metallacages are scarcely toxic in vitro. The marked fluorescence due to BODIPY allowed us to visualise the cages' uptake and sub-cellular localisation inside melanoma cells using fluorescence microscopy, highlighting uptake via active transport mechanisms and accumulation in cytoplasmic vesicles.


Asunto(s)
Antineoplásicos/química , Compuestos de Boro/química , Complejos de Coordinación/química , Complejos de Coordinación/farmacología , Antineoplásicos/farmacología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Cisplatino/química , Cisplatino/farmacología , Glutatión/metabolismo , Humanos , Espectroscopía de Resonancia Magnética , Microscopía Confocal , Microscopía Fluorescente , Paladio/química , Porfobilinógeno/análogos & derivados , Porfobilinógeno/química
9.
Chemistry ; 25(46): 10895-10906, 2019 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-31127668

RESUMEN

The first example of an octadentate gadolinium unit based on DO3A (hydration number q=1) with a dithiocarbamate tether has been designed and attached to the surface of gold nanoparticles (around 4.4 nm in diameter). In addition to the superior robustness of this attachment, the restricted rotation of the Gd complex on the nanoparticle surface leads to a dramatic increase in relaxivity (r1 ) from 4.0 mm-1 s-1 in unbound form to 34.3 mm-1 s-1 (at 10 MHz, 37 °C) and 22±2 mm-1 s-1 (at 63.87 MHz, 25 °C) when immobilised on the surface. The one-pot synthetic route provides a straightforward and versatile way of preparing a range of multifunctional gold nanoparticles. The incorporation of additional surface units for biocompatibility (PEG and thioglucose units) and targeting (folic acid) leads to little detrimental effect on the high relaxivity observed for these non-toxic multifunctional materials. In addition to the passive targeting attributed to gold nanoparticles, the inclusion of a unit capable of targeting the folate receptors overexpressed by cancer cells, such as HeLa cells, illustrates the potential of these assemblies.

10.
Mol Pharm ; 16(7): 3199-3207, 2019 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-31125239

RESUMEN

Polymer masked-unmasked protein therapy (PUMPT) uses conjugation of a biodegradable polymer, such as dextrin, hyaluronic acid, or poly(l-glutamic acid), to mask a protein or peptide's activity; subsequent locally triggered degradation of the polymer at the target site regenerates bioactivity in a controllable fashion. Although the concept of PUMPT is well established, the relationship between protein unmasking and reinstatement of bioactivity is unclear. Here, we used dextrin-colistin conjugates to study the relationship between the molecular structure (degree of unmasking) and biological activity. Size exclusion chromatography was employed to collect fractions of differentially degraded conjugates and ultraperformance liquid chromatography-mass spectrometry (UPLC-MS) employed to characterize the corresponding structures. Antimicrobial activity was studied using a minimum inhibitory concentration (MIC) assay and confocal laser scanning microscopy of LIVE/DEAD-stained biofilms with COMSTAT analysis. In vitro toxicity of the degraded conjugate was assessed using an 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay. UPLC-MS revealed that the fully "unmasked" dextrin-colistin conjugate composed of colistin bound to at least one linker, whereas larger species were composed of colistin with varying lengths of glucose units attached. Increasing the degree of dextrin modification by succinoylation typically led to a greater number of linkers bound to colistin. Greater antimicrobial and antibiofilm activity were observed for the fully "unmasked" conjugate compared to the partially degraded species (MIC = 0.25 and 2-8 µg/mL, respectively), whereas dextrin conjugation reduced colistin's in vitro toxicity toward kidney cells, even after complete unmasking. This study highlights the importance of defining the structure-antimicrobial activity relationship for novel antibiotic derivatives and demonstrates the suitability of LC-MS to aid the design of biodegradable polymer-antibiotic conjugates.


Asunto(s)
Amilasas/metabolismo , Colistina/química , Colistina/metabolismo , Dextrinas/química , Dextrinas/metabolismo , Composición de Medicamentos/métodos , Sistemas de Liberación de Medicamentos/métodos , Antibacterianos/química , Antibacterianos/metabolismo , Biopelículas/efectos de los fármacos , Línea Celular , Supervivencia Celular/efectos de los fármacos , Cromatografía en Gel , Escherichia coli/efectos de los fármacos , Humanos , Túbulos Renales Proximales/citología , Espectrometría de Masas , Pruebas de Sensibilidad Microbiana , Microscopía Confocal , Estructura Molecular
11.
Chemistry ; 25(32): 7628-7634, 2019 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-30990916

RESUMEN

With the aim of exploiting the use of organometallic species for the efficient modification of proteins through C-atom transfer, the gold-mediated cysteine arylation through a reductive elimination process occurring from the reaction of cyclometalated AuIII C^N complexes with a zinc finger peptide (Cys2 His2 type) is here reported. Among the four selected AuIII cyclometalated compounds, the [Au(CCO N)Cl2 ] complex featuring the 2-benzoylpyridine (CCO N) scaffold was identified as the most prone to reductive elimination and Cys arylation in buffered aqueous solution (pH 7.4) at 37 °C by high-resolution LC electrospray ionization mass spectrometry. DFT and quantum mechanics/molecular mechanics (QM/MM) studies permitted to propose a mechanism for the title reaction that is in line with the experimental results. Overall, the results provide new insights into the reactivity of cytotoxic organogold compounds with biologically important zinc finger domains and identify initial structure-activity relationships to enable AuIII -catalyzed reductive elimination in aqueous media.


Asunto(s)
Complejos de Coordinación/química , Cisteína/química , Oro/química , Dedos de Zinc , Modelos Moleculares , Dominios Proteicos , Teoría Cuántica , Termodinámica
12.
ACS Med Chem Lett ; 10(4): 564-570, 2019 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-30996797

RESUMEN

The nickel-dependent enzyme urease is a virulence factor for a large number of critical human pathogens, making this enzyme a potential target of therapeutics for the treatment of resistant bacterial infections. In the search for novel urease inhibitors, five selected coordination and organometallic Au(III) compounds containing N∧N or C∧N and C∧N∧N ligands were tested for their inhibitory effects against Canavalia ensiformis (jack bean) urease. The results showed potent inhibition effects with IC50 values in the nanomolar range. The 2.14 Å resolution crystal structure of Sporosarcina pasteurii urease inhibited by the most effective Au(III) compound [Au(PbImMe)Cl2]PF6 (PbImMe = 1-methyl-2-(pyridin-2-yl)-benzimidazole) reveals the presence of two Au ions bound to the conserved triad αCys322/αHis323/αMet367. The binding of the Au ions to these residues blocks the movement of a flap, located at the edge of the active site channel and essential for enzyme catalysis, completely obliterating the catalytic activity of urease. Overall, the obtained results constitute the basis for the design of new gold complexes as selective urease inhibitors with future antibacterial applications.

14.
Front Chem ; 7: 68, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30834242

RESUMEN

Within the framework of designing new self-assembled metallosupramolecular architectures for drug delivery, seven [Pd2L4]4+ metallacages (L = 2,6-bis(pyridine-3-ylethynyl)pyridine) featuring different groups in exo-position, selected to enhance the cage solubility in aqueous environment, were synthesized. Thus, carboxylic acids, sugars, and PEG groups were tethered to the bispyridyl ligands directly or via disulfide bond formation, as well as via click chemistry. The ligands and respective cages were characterized by different methods, including NMR spectroscopy and high-resolution electrospray mass spectrometry (HR-ESI-MS). While the two ligands featuring carboxylic acid-functionalized groups showed improved solubility in water, the other ligands were soluble only in organic solvents. Unfortunately, all the respective self-assembled cages were also insoluble in water. Afterwards, the encapsulation properties of the anticancer drug cisplatin in selected [Pd2L4]X4 cages (X = NO 3 - , BF 4 - ) were studied by 1H, 1H DOSY, and 195Pt NMR spectroscopy. The effect of the counter ions as well as of the polarity of the solvent in the drug encapsulation process were also investigated, and provided useful information on the host-guest properties of these experimental drug delivery systems. Our results provide further experimental support for previous studies that suggest the desolvation of guests from surrounding solvent molecules and the resulting solvent rearrangement may actually be the primary driving force for determining guest binding affinities in metallacages, in the absence of specific functional group interactions.

15.
Inorg Chem ; 58(3): 2140-2148, 2019 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-30645101

RESUMEN

Following our recent reports on the inhibition of the water and glycerol channel aquaglyceroporin-3 (AQP3) by the coordination complex [AuIII(1,10-phenanthroline)Cl2] (Auphen), a series of six new Au(III) complexes featuring substituted 1,10-phenanthroline ligands (1-6) have been synthesized and characterized. The speciation of the compounds studied in buffered solution by UV-visible spectrophotometry showed that most of the complexes remain stable for several hours. Quantum mechanics (QM) studies of the hydrolysis processes of the compounds suggest that they are thermodynamically less prone to exchange the chlorido ligands with H2O or OH- in comparison to Au(III) bipyridyl complexes. Preliminary data on the antiproliferative activity against A549 human lung cancer cells indicate that the compounds are able to inhibit cell proliferation in vitro. Stopped-flow spectroscopy showed that these complexes potently inhibit glycerol permeation in human red blood cells (hRBC) through AQP3 blockage. The QM investigation of the ligand exchange with methanethiol, used as a model of Cys40 of AQP3, was carried out for some derivatives and showed that the affinity of the compounds' binding for thiols is higher in comparison to the Aubipy complex ([AuIII(bipy)Cl2]PF6, bipy = 2,2'-bipyridine). In addition, both noncovalent and coordinative binding of complex 3 ( [AuIII(5-chloro-1,10-phenanthroline)Cl2]PF6) to the protein channel has been investigated in comparison to the benchmark Auphen and Aubipy using a computational workflow, including QM, molecular dynamics (MD), and quantum mechanics/molecular mechanics (QM/MM) approaches. Finally, atoms in molecules (AIM) and natural bond orbital (NBO) analyses corroborate the MD predictions, providing quantification of the noncoordinative interactions between the compounds and AQP3. AQP3 inhibition is the result of protein conformational changes, upon coordinative gold binding, which induce pore closure. The importance of noncoordinative adducts in modulating the AQP3 inhibition properties of the investigated Au(III) compounds has been elucidated, and these interactions should be further considered in the future design of isoform-selective AQP inhibitors.

16.
Bioconjug Chem ; 29(11): 3856-3865, 2018 11 21.
Artículo en Inglés | MEDLINE | ID: mdl-30380298

RESUMEN

Cisplatin occupies a crucial role in the treatment of various malignant tumors. However, its efficacy and applicability are heavily restricted by severe systemic toxicities and drug resistance. Our study exploits the active targeting of supramolecular metallacages to enhance the activity of cisplatin in cancer cells while reducing its toxicity. Thus, Pd2L4 cages (L = ligand) have been conjugated to four integrin ligands with different binding affinity and selectivity. Cage formation and encapsulation of cisplatin was proven by NMR spectroscopy. Upon encapsulation, cisplatin showed increased cytotoxicity in vitro, in melanoma A375 cells overexpressing αvß3 integrins. Moreover, ex vivo studies in tissue slices indicated reduced toxicity toward healthy liver and kidney tissues for cage-encapsulated cisplatin. Analysis of metal content by ICP-MS demonstrated that the encapsulated drug is less accumulated in these organs compared to the "free" cisplatin.


Asunto(s)
Antineoplásicos/administración & dosificación , Cisplatino/administración & dosificación , Portadores de Fármacos/metabolismo , Integrina alfaVbeta3/metabolismo , Melanoma/tratamiento farmacológico , Estructuras Metalorgánicas/metabolismo , Paladio/metabolismo , Animales , Antineoplásicos/farmacología , Línea Celular Tumoral , Cisplatino/farmacología , Portadores de Fármacos/química , Sistemas de Liberación de Medicamentos , Humanos , Ligandos , Masculino , Melanoma/metabolismo , Estructuras Metalorgánicas/química , Paladio/química , Ratas Wistar
17.
J Clin Virol ; 108: 50-52, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30240941

RESUMEN

BACKGROUND: Plasma HIV-1 RNA (viral load, VL) is measured routinely in HIV-infected persons with FDA-approved commercially available assays such as the Cobas-TaqMan HIV-1 Assay v2.0. This assay provides quantification of viremia ≥20 copies/mL. More sensitive methods, able to quantify low-level persistent viremia below the detection limit of commercially available assays, are needed to assess the impact of current HIV cure strategies on viremia. OBJECTIVES: The novel integrase HIV-1 RNA single-copy assay (iSCA) was evaluated for measurement of low-level persistent viremia in clinical trial samples (n = 151) from subjects participating in Gilead HIV clinical research. STUDY DESIGN: Paired plasma samples from HIV-1-infected patients treated with combination ART were assessed using both HIV-1 Cobas-TaqMan and iSCA; results from the two assays were compared. RESULTS: Paired Cobas-TaqMan/iSCA data were obtained for 151 HIV-infected adults. Most samples (117/151, 77%) had non-quantifiable Cobas-TaqMan result, either <20 copies/mL ("<20") or "Target Not Detected" (TND). All 117 non-quantified samples were quantified with iSCA and showed higher HIV-1 RNA levels in samples with <20 than TND Cobas-TaqMan results (p < 0.0001). CONCLUSIONS: In this large sample collection from virologically suppressed HIV-infected adults, use of iSCA led to quantification of low-level viremia below the limit of detection of the Cobas-TaqMan assay in all 117 previously non-quantifiable plasma samples. These data confirm the value of the iSCA as a helpful addition to the classical HIV VL assays and its potential for use in HIV cure studies to assess whether experimental interventions alter viremia.


Asunto(s)
Infecciones por VIH/diagnóstico , Integrasa de VIH/genética , ARN Viral/sangre , Carga Viral/métodos , Adulto , VIH-1/enzimología , VIH-1/genética , Humanos , Límite de Detección , Masculino , Plasma , Juego de Reactivos para Diagnóstico , Sensibilidad y Especificidad , Viremia/diagnóstico
18.
Chem Commun (Camb) ; 54(6): 611-614, 2018 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-29292454

RESUMEN

The binding of Au(iii) complexes to the zinc finger domain of the anticancer drug target PARP-1 was studied using a hyphenated mass spectrometry approach combined with quantum mechanics/molecular mechanics (QM/MM) studies. Competition experiments were carried out, whereby each Au complex was exposed to two types of zinc fingers. Notably, the cyclometallated Au-C^N complex was identified as the most selective candidate to disrupt the PARP-1 zinc finger domain, forming distinct adducts compared to the coordination compound Auphen.

19.
J Am Chem Soc ; 139(3): 1177-1190, 2017 01 25.
Artículo en Inglés | MEDLINE | ID: mdl-28075565

RESUMEN

NaNO3 is used in oxidative Pd-catalyzed processes as a complementary co-catalyst to common oxidants, e.g., CuII salts, in C-H bond activation and Wacker oxidation processes. NaNO3 and NaNO2 (with air or O2) assist the sp3-C-H bond acetoxylation of substrates bearing an N-directing group. It has been proposed previously that a redox couple is operative. The role played by NOx anions is examined in this investigation. Evidence for an NOx anion interaction at PdII is presented. Palladacyclic complexes containing NOx anions are competent catalysts for acetoxylation of 8-methylquinoline, with and without exogenous NaNO3. The oxidation of 8-methylquinoline to the corresponding carboxylic acid has also been noted at PdII. 18O-Labeling studies indicate that oxygen derived from nitrate appears in the acetoxylation product, the transfer of which can only occur by interaction of 18O at Pd with a coordinating-acetate ligand. Nitrated organic intermediates are formed under catalytic conditions, which are converted to acetoxylation products, a process that occurs with (50 °C) and without Pd (110 °C). A catalytically competent palladacyclic dimer intermediate has been identified. Head-space analysis measurements show that NO and NO2 gases are formed within minutes on heating catalytic mixtures to 110 °C from room temperature. Measurements by in situ infrared spectroscopy show that N2O is formed in sp3-C-H acetoxylation reactions at 80 °C. Studies confirm that cyclopalladated NO2 complexes are rapidly oxidized to the corresponding NO3 adducts on exposure to NO2(g). The investigation shows that NOx anions act as participating ligands at PdII in aerobic sp3-C-H bond acetoxylation processes and are involved in redox processes.

20.
Inorg Chem ; 55(24): 12982-12996, 2016 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-27989205

RESUMEN

The disulfide ligand (SC6H4CO2H-4)2 acts as a simple but versatile linker for a range of group 8 transition metals through reaction of the oxygen donors. This leads to a range of homobimetallic ruthenium and osmium alkenyl compounds, [{M(CH═CHR)(CO)(PPh3)2(O2CC6H4S-4)}2] (M = Ru, Os; R = C6H4Me-4). Additional metal-based functionality can be added through the use of precursors incorporating rhenium bipyridine units (R = (bpy)ReCl(CO)3). The more robust diphosphine ligands in [{Ru(dppm)2(O2CC6H4S-4)}2]2+ (dppm = diphenylphosphinomethane) allow reduction of the disulfide bond with sodium borohydride to yield the thiol complex [Ru(O2CC6H4SH-4)(dppm)2]+. This complex reacts with [AuCl(PPh3)] to afford the bimetallic compound [Ru(dppm)2(O2CC6H4S-4)Au(PPh3)]+. However, an improved route to the same and related heterobimetallic compounds is provided by the reaction of cis-[RuCl2(dppm)2] with [Au(SC6H4CO2H-4)(L)] (L = PPh3, PCy3, PMe3, IDip) in the presence of base and NH4PF6 (IDip = 1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene). The heterotrimetallic compound [Au(SC6H4CO2Ru(dppm)2)2]+ is accessible through the reaction of the homoleptic gold(I) dithiolate [Au(SC6H4CO2H-4)2]PPN (PPN = bis(triphenylphosphine)iminium) with cis-[RuCl2(dppm)2]. Without departure from the same methodology, greater complexity can be incorporated into the system to provide the penta- and heptametallic assemblies [(dppf){AuSC6H4CO2Ru(dppm)2}2]2+ and [(dppf){AuSC6H4CO2Os(CH═CH-bpyReCl(CO)3)(CO)(PPh3)2}2]. The same stepwise approach provides the dinuclear organometallic complexes [(L)Au(SC6H4CO2-4)M(CH═CHC6H4Me-4)(CO)(PPh3)2] (M = Ru, Os; L = PPh3, IDip). Complexes containing three metals from different groups of the periodic table [(L)Au(SC6H4CO2-4)M{CH═CH-bpyReCl(CO)3}(CO)(PPh3)2] (M = Ru, Os) can also be prepared, with one ruthenium example (L = PPh3) being structurally characterized. In order to illustrate the versatility of this approach, the synthesis and characterization (IR and NMR spectroscopy, TEM, EDS, and TGA) of the functionalized gold and palladium nanoparticles Au@[SC6H4CO2Ru(dppm)2]+ and Pd@[SC6H4CO2Ru(dppm)2]+ is reported.

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