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1.
Ann Intern Med ; 177(6): 729-737, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38710093

RESUMEN

BACKGROUND: Giant cell arteritis (GCA) is the most prevalent systemic vasculitis in people older than 50 years. Any delay in diagnosis impairs patients' quality of life and can lead to permanent damage, particularly vision loss. OBJECTIVE: To evaluate a diagnostic strategy for GCA using color Doppler ultrasound of the temporal artery as a first-line diagnostic test, temporal artery biopsy (TAB) as a secondary test, and physician expertise as the reference method. DESIGN: Prospective multicenter study with a 2-year follow-up. (ClinicalTrials.gov: NCT02703922). SETTING: Patients were referred by their general practitioner or ophthalmologist to a physician with extensive experience in GCA diagnosis and management in one of the participating centers: 4 general and 2 university hospitals. PATIENTS: 165 patients with high clinical suspicion of GCA, aged 79 years (IQR, 73 to 85 years). INTERVENTION: The diagnostic procedure was ultrasound, performed less than 7 days after initiation of corticosteroid therapy. Only ultrasound-negative patients underwent TAB. MEASUREMENTS: Bilateral temporal halo signs seen on ultrasound were considered positive. Ultrasound and TAB results were compared with physician-diagnosed GCA based on clinical findings and other imaging. RESULTS: Diagnosis of GCA was confirmed in 44%, 17%, and 21% of patients by ultrasound, TAB, and clinical expertise and/or other imaging tests, respectively. Their diagnosis remained unchanged at 1 month, and 2 years for those with available follow-up data. An alternative diagnosis was made in 18% of patients. The proportion of ultrasound-positive patients among patients with a clinical GCA diagnosis was 54% (95% CI, 45% to 62%). LIMITATION: Small sample size, no blinding of ultrasound and TAB results, lack of an objective gold-standard comparator, and single diagnostic strategy. CONCLUSION: By using ultrasound of the temporal arteries as a first-line diagnostic tool in patients with high clinical suspicion of GCA, further diagnostic tests for patients with positive ultrasound were avoided. PRIMARY FUNDING SOURCE: Tender "Recherche CH-CHU Poitou-Charentes 2014."


Asunto(s)
Arteritis de Células Gigantes , Arterias Temporales , Ultrasonografía Doppler en Color , Humanos , Arteritis de Células Gigantes/diagnóstico por imagen , Arterias Temporales/diagnóstico por imagen , Arterias Temporales/patología , Estudios Prospectivos , Anciano , Femenino , Masculino , Anciano de 80 o más Años , Biopsia
2.
J Am Soc Nephrol ; 2024 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-38995699

RESUMEN

BACKGROUND: Endothelin receptor antagonists (ERAs) reduce albuminuria but are limited by fluid retention risk, particularly in patients with chronic kidney disease (CKD). Combining ERAs with sodium-glucose cotransporter 2 (SGLT2) inhibitors, which have diuretic effects, offers a promising strategy to mitigate fluid retention. In this post-hoc analysis of the ZENITH-CKD trial, we assessed fluid dynamics in patients with CKD treated with the ERA zibotentan alone, and in combination with the SGLT2 inhibitor dapagliflozin. METHODS: In ZENITH-CKD, 508 patients with CKD (estimated glomerular filtration rate ≥ 20 mL/min/1.73m2 and a urinary albumin-to-creatinine ratio of 150-5000 mg/g) were randomized to treatment with placebo, dapagliflozin 10 mg plus placebo, zibotentan (0.25, 1.5 or 5 mg) plus dapagliflozin 10 mg and zibotentan 5 mg plus placebo. We evaluated correlations between changes in fluid retention markers and bioimpedance-measured extracellular fluid (ECF) in response to zibotentan treatment. We used Cox proportional hazards regression to assess the association between zibotentan/dapagliflozin treatment, baseline characteristics, and fluid retention, and the relationship between zibotentan plasma exposure and fluid retention. RESULTS: After 3 weeks of treatment with zibotentan 0.25, 1.5 or 5 mg plus dapagliflozin 10 mg, changes in body weight (ß=0.36 [95%CI 0.26,0.45]) per kg, B-type natriuretic peptide (ß=0.38 [95%CI 0.22, 0.54]) per doubling, and hemoglobin (ß=-0.29 [95%CI -0.48, -0.10]) per g/dL were independently associated with changes in ECF. Higher doses of zibotentan were associated with significantly higher risk of fluid retention compared to dapagliflozin alone (zibotentan 5 mg HR 8.50 (95%CI 3.40, 21.30). The hazard ratio attenuated when zibotentan was combined with dapagliflozin (HR zibotentan/dapagliflozin 5/10 mg 3.09 [95%CI 1.08, 8.80], zibotentan/dapagliflozin 1.5/10 mg 2.70 [95%CI 1.44, 5.07] and zibotentan/dapagliflozin 0.25/10 mg HR 1.21 [95%CI 0.50, 2.91]). The risk of fluid retention was higher with higher zibotentan exposure and lower eGFR. CONCLUSIONS: High doses of zibotentan were associated with a higher risk of fluid retention, which was attenuated with lower doses and the addition of dapagliflozin.

3.
Lancet ; 402(10416): 2004-2017, 2023 11 25.
Artículo en Inglés | MEDLINE | ID: mdl-37931629

RESUMEN

BACKGROUND: In patients with chronic kidney disease, SGLT2 inhibitors and endothelin A receptor antagonists (ERAs) can reduce albuminuria and glomerular filtration rate (GFR) decline. We assessed the albuminuria-lowering efficacy and safety of the ERA zibotentan combined with the SGLT2 inhibitor dapagliflozin. METHODS: ZENITH-CKD was a multicentre, randomised, double-blind, active-controlled clinical trial, done in 170 clinical practice sites in 18 countries. Adults (≥18 to ≤90 years) with an estimated GFR (eGFR) of 20 mL/min per 1·73 m2 or greater and a urinary albumin-to-creatinine ratio (UACR) of 150-5000 mg/g were randomly assigned (2:1:2) to 12 weeks of daily treatment with zibotentan 1·5 mg plus dapagliflozin 10 mg, zibotentan 0·25 mg plus dapagliflozin 10 mg, or dapagliflozin 10 mg plus placebo, as adjunct to angiotensin-converting enzyme inhibitors or angiotensin receptor blockers if tolerated. The primary endpoint was a change from baseline in log-transformed UACR (zibotentan 1·5 mg plus dapagliflozin vs dapagliflozin plus placebo) at week 12. Fluid retention was an event of special interest, defined as an increase in bodyweight of at least 3% (at least 2·5% must have been from total body water) from baseline or an increase of at least 100% in B-type natriuretic peptide (BNP) and either a BNP concentration greater than 200 pg/mL if without atrial fibrillation or BNP greater than 400 pg/mL if with atrial fibrillation. This trial is registered with ClinicalTrials.gov, NCT04724837, and is completed. FINDINGS: Between April 28, 2021, and Jan 17, 2023, we assessed 1492 participants for eligibility. For the main analysis, we randomly assigned 449 (30%) participants, 447 (99%) of whom (mean age 62·8 years [SD 12·1], 138 [31%] female, 309 [69%] male, 305 [68%] White, mean eGFR 46·7 mL/min per 1·73 m2 [SD 22·4], and median UACR 565·5 mg/g [IQR 243·0-1212·6]) received treatment with zibotentan 1·5 mg plus dapagliflozin (n=179 [40%]), zibotentan 0·25 mg plus dapagliflozin (n=91 [20%]), or dapagliflozin plus placebo (n=177 [40%]). Zibotentan 1·5 mg plus dapagliflozin and zibotentan 0·25 mg plus dapagliflozin reduced UACR versus dapagliflozin plus placebo throughout the treatment period of the study. At week 12, the difference in UACR versus dapagliflozin plus placebo was -33·7% (90% CI -42·5 to -23·5; p<0·0001) for zibotentan 1·5 mg plus dapagliflozin and -27·0% (90% CI -38·4 to -13·6; p=0·0022) for zibotentan 0·25 mg plus dapagliflozin. Fluid-retention events were observed in 33 (18%) of 179 participants in the zibotentan 1·5 mg plus dapagliflozin group, eight (9%) of 91 in the zibotentan 0·25 mg plus dapagliflozin group, and 14 (8%) of 177 in the dapagliflozin plus placebo group. INTERPRETATION: Zibotentan combined with dapagliflozin reduced albuminuria with an acceptable tolerability and safety profile and is an option to reduce chronic kidney disease progression in patients already receiving currently recommended therapy. FUNDING: AstraZeneca.


Asunto(s)
Fibrilación Atrial , Diabetes Mellitus Tipo 2 , Insuficiencia Renal Crónica , Inhibidores del Cotransportador de Sodio-Glucosa 2 , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Albuminuria , Fibrilación Atrial/tratamiento farmacológico , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Método Doble Ciego , Tasa de Filtración Glomerular , Insuficiencia Renal Crónica/complicaciones , Insuficiencia Renal Crónica/tratamiento farmacológico , Inhibidores del Cotransportador de Sodio-Glucosa 2/uso terapéutico , Anciano , Anciano de 80 o más Años
4.
Nephrol Dial Transplant ; 39(3): 414-425, 2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-37632201

RESUMEN

BACKGROUND: Sodium-glucose co-transporter 2 inhibitors (SGLT2is) are part of the standard of care for patients with chronic kidney disease (CKD), both with and without type 2 diabetes. Endothelin A (ETA) receptor antagonists have also been shown to slow progression of CKD. Differing mechanisms of action of SGLT2 and ETA receptor antagonists may enhance efficacy. We outline a study to evaluate the effect of combination zibotentan/dapagliflozin versus dapagliflozin alone on albuminuria and estimated glomerular filtration rate (eGFR). METHODS: We are conducting a double-blind, active-controlled, Phase 2b study to evaluate the efficacy and safety of ETA receptor antagonist zibotentan and SGLT2i dapagliflozin in a planned 415 adults with CKD (Zibotentan and Dapagliflozin for the Treatment of CKD; ZENITH-CKD). Participants are being randomized (1:2:2) to zibotentan 0.25 mg/dapagliflozin 10 mg once daily (QD), zibotentan 1.5 mg/dapagliflozin 10 mg QD and dapagliflozin 10 mg QD alone, for 12 weeks followed by a 2-week off-treatment wash-out period. The primary endpoint is the change in log-transformed urinary albumin-to-creatinine ratio (UACR) from baseline to Week 12. Other outcomes include change in blood pressure from baseline to Week 12 and change in eGFR the study. The incidence of adverse events will be monitored. Study protocol-defined events of special interest include changes in fluid-related measures (weight gain or B-type natriuretic peptide). RESULTS: A total of 447 patients were randomized and received treatment in placebo/dapagliflozin (n = 177), zibotentan 0.25 mg/dapagliflozin (n = 91) and zibotentan 1.5 mg/dapagliflozin (n =  179). The mean age was 62.8 years, 30.9% were female and 68.2% were white. At baseline, the mean eGFR of the enrolled population was 46.7 mL/min/1.73 m2 and the geometric mean UACR was 538.3 mg/g. CONCLUSION: This study evaluates the UACR-lowering efficacy and safety of zibotentan with dapagliflozin as a potential new treatment for CKD. The study will provide information about an effective and safe zibotentan dose to be further investigated in a Phase 3 clinical outcome trial. CLINICAL TRIAL REGISTRATION NUMBER: NCT04724837.


Asunto(s)
Compuestos de Bencidrilo , Diabetes Mellitus Tipo 2 , Glucósidos , Pirrolidinas , Insuficiencia Renal Crónica , Inhibidores del Cotransportador de Sodio-Glucosa 2 , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Método Doble Ciego , Insuficiencia Renal Crónica/complicaciones , Insuficiencia Renal Crónica/tratamiento farmacológico , Insuficiencia Renal Crónica/inducido químicamente , Inhibidores del Cotransportador de Sodio-Glucosa 2/efectos adversos
5.
BMC Gastroenterol ; 23(1): 451, 2023 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-38124112

RESUMEN

BACKGROUND: Short-term efficacy and safety of brazikumab (MEDI2070), a human monoclonal antibody and anti-p19 subunit inhibitor of interleukin-23, was demonstrated in a phase 2a trial in patients with moderate-to-severe active Crohn's disease (CD). We report brazikumab long-term safety and tolerability from the open-label period of this phase 2a study. METHODS: Patients who completed the 12-week, double-blind induction period were eligible for inclusion in an open-label period where all patients received subcutaneous brazikumab (210 mg) every 4 weeks for 100 weeks. Patients had moderate-to-severe active CD and had failed or were intolerant to ≥ 1 anti-tumour necrosis factor alpha (TNFα) agent. Safety assessments included treatment-emergent adverse events (TEAEs); further assessments were pharmacokinetics and immunogenicity. RESULTS: Of the 104 patients who entered the open-label period, 57 (54.8%) continued to the end of the open-label period and 47 (45.2%) discontinued brazikumab. The most common reasons for discontinuation were lack of response (14.4%), patient decision (12.5%), and TEAEs (11.5%). In total, 44 (84.6%) in the group switching from placebo to brazikumab (placebo/brazikumab) and 43 (82.7%) in the group continuing brazikumab (brazikumab/brazikumab) experienced 1 or more TEAEs. Most TEAEs were mild-to-moderate in severity. Common TEAEs included nasopharyngitis and headache. Numbers of treatment-emergent serious adverse events (TESAEs) were similar between groups. Infections occurred in 40.4% of patients in the placebo/brazikumab group and 50% in the brazikumab/brazikumab group. There were 5 TESAEs of infection, none of which were opportunistic. No major adverse cardiac events, malignancies, or deaths were reported. CONCLUSIONS: Brazikumab was well tolerated with an acceptable safety profile over a 100-week period in patients with moderate-to-severe active CD who failed or were intolerant to 1 or more anti-TNFα agents. TRIAL REGISTRATION: NCT01714726; registered October 26, 2012.


Asunto(s)
Enfermedad de Crohn , Humanos , Enfermedad de Crohn/tratamiento farmacológico , Enfermedad de Crohn/inducido químicamente , Anticuerpos Monoclonales/efectos adversos , Interleucina-23 , Cefalea , Método Doble Ciego , Resultado del Tratamiento
6.
Int J Mol Sci ; 24(4)2023 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-36835001

RESUMEN

Radiation resistance and radiation-related side effects warrant research into alternative strategies in the application of this modality to cancer treatment. Designed in silico to improve the pharmacokinetics and anti-cancer properties of 2-methoxyestradiol, 2-ethyl-3-O-sulfamoyl-estra-1,3,5(10)16-tetraene (ESE-16) disrupts microtubule dynamics and induces apoptosis. Here, we investigated whether pre-exposure of breast cancer cells to low-dose ESE-16 would affect radiation-induced deoxyribonucleic acid (DNA) damage and the consequent repair pathways. MCF-7, MDA-MB-231, and BT-20 cells were exposed to sub-lethal doses of ESE-16 for 24 h before 8 Gy radiation. Flow cytometric quantification of Annexin V, clonogenic studies, micronuclei quantification, assessment of histone H2AX phosphorylation and Ku70 expression were performed to assess cell viability, DNA damage, and repair pathways, in both directly irradiated cells and cells treated with conditioned medium. A small increase in apoptosis was observed as an early consequence, with significant repercussions on long-term cell survival. Overall, a greater degree of DNA damage was detected. Moreover, initiation of the DNA-damage repair response was delayed, with a subsequent sustained elevation. Radiation-induced bystander effects induced similar pathways and were initiated via intercellular signaling. These results justify further investigation of ESE-16 as a radiation-sensitizing agent since pre-exposure appears to augment the response of tumor cells to radiation.


Asunto(s)
Neoplasias de la Mama , Daño del ADN , Reparación del ADN , Estrenos , Femenino , Humanos , 2-Metoxiestradiol/análogos & derivados , 2-Metoxiestradiol/farmacología , Apoptosis , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/radioterapia , Línea Celular Tumoral , Daño del ADN/efectos de los fármacos , Daño del ADN/efectos de la radiación , Reparación del ADN/efectos de los fármacos , Reparación del ADN/efectos de la radiación , Estrenos/farmacología , Estrenos/uso terapéutico , Sulfonamidas/farmacología , Sulfonamidas/uso terapéutico
7.
Molecules ; 27(12)2022 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-35744942

RESUMEN

A tetrahydroisoquinoline (THIQ) core is able to mimic the A and B rings of 2-methoxyestradiol (2ME2), an endogenous estrogen metabolite that demonstrates promising anticancer properties primarily by disrupting microtubule dynamic instability parameters, but has very poor pharmaceutical properties that can be improved by sulfamoylation. The non-steroidal THIQ-based microtubule disruptor 2-(3-bromo-4,5-dimethoxybenzyl)-7-methoxy-6-sulfamoyloxy-1,2,3,4-tetrahydroisoquinoline (STX3451), with enhanced pharmacokinetic and pharmacodynamic profiles, was explored for the first time in radiation biology. We investigated whether 24 h pre-treatment with STX3451 could pre-sensitize MCF-7 and MDA-MB-231 breast cancer cells to radiation. This regimen showed a clear increase in cytotoxicity compared to the individual modalities, results that were contiguous in spectrophotometric analysis, flow cytometric quantification of apoptosis induction, clonogenic studies and microscopy techniques. Drug pre-treatment increased radiation-induced DNA damage, with statistically more double-strand (ds) DNA breaks demonstrated. The latter could be due to the induction of a radiation-sensitive metaphase block or the increased levels of reactive oxygen species, both evident after compound exposure. STX3451 pre-exposure may also delay DNA repair mechanisms, as the DNA damage response element ataxia telangiectasia mutated (ATM) was depressed. These in vitro findings may translate into in vivo models, with the ultimate aim of reducing both radiation and drug doses for maximal clinical effect with minimal adverse effects.


Asunto(s)
Neoplasias de la Mama , Tetrahidroisoquinolinas , 2-Metoxiestradiol/farmacología , Apoptosis , Neoplasias de la Mama/metabolismo , Línea Celular Tumoral , Femenino , Humanos , Células MCF-7 , Microtúbulos/metabolismo , Ácidos Sulfónicos , Tetrahidroisoquinolinas/farmacología
8.
Molecules ; 26(3)2021 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-33572896

RESUMEN

The search for novel anti-cancer compounds which can circumvent chemotherapeutic drug resistance and limit systemic toxicity remains a priority. 2-Ethyl-3-O-sulphamoyl-estra-1,3,5(10)15-tetraene-3-ol-17one (ESE-15-one) and 2-ethyl-3-O-sulphamoyl-estra-1,3,5(10)16-tetraene (ESE-16) are sulphamoylated 2-methoxyestradiol (2-ME) analogues designed by our research team. Although their cytotoxicity has been demonstrated in vitro, the temporal and mechanistic responses of the initiated intracellular events are yet to be determined. In order to do so, assays investigating the compounds' effects on microtubules, cell cycle progression, signalling cascades, autophagy and apoptosis were conducted using HeLa cervical- and MDA-MB-231 metastatic breast cancer cells. Both compounds reversibly disrupted microtubule dynamics as an early event by binding to the microtubule colchicine site, which blocked progression through the cell cycle at the G1/S- and G2/M transitions. This was supported by increased pRB and p27Kip1 phosphorylation. Induction of apoptosis with time-dependent signalling involving the p-JNK, Erk1/2 and Akt/mTOR pathways and loss of mitochondrial membrane potential was demonstrated. Inhibition of autophagy attenuated the apoptotic response. In conclusion, the 2-ME analogues induced a time-dependent cross-talk between cell cycle checkpoints, apoptotic signalling and autophagic processes, with an increased reactive oxygen species formation and perturbated microtubule functioning appearing to connect the processes. Subtle differences in the responses were observed between the two compounds and the different cell lines.


Asunto(s)
Apoptosis/efectos de los fármacos , Autofagia/efectos de los fármacos , Neoplasias de la Mama/tratamiento farmacológico , Estrona/farmacología , Neoplasias del Cuello Uterino/tratamiento farmacológico , Antineoplásicos/farmacología , Apoptosis/genética , Autofagia/genética , Neoplasias de la Mama/patología , Muerte Celular/efectos de los fármacos , Muerte Celular/genética , Línea Celular Tumoral , Estrenos/farmacología , Estrona/análogos & derivados , Estrona/química , Femenino , Células HeLa , Humanos , Microtúbulos/química , Metástasis de la Neoplasia , Transducción de Señal/efectos de los fármacos , Sulfonamidas/farmacología , Neoplasias del Cuello Uterino/patología
9.
Adv Exp Med Biol ; 1083: 89-102, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29139089

RESUMEN

The recurrence and/or lack of response of certain tumors to radio- and chemotherapy has been attributed to a small subpopulation of cells termed cancer stem cells (CSCs). CSCs have been identified in many tumors (including solid and hematological tumors). CSCs are characterized by their capacity for self-renewal, their ability to introduce heterogeneity within a tumor mass and its metastases, genomic instability, and their insensitivity to both radiation and chemotherapy. The latter highlights the clinical importance of studying this subpopulation since their resistance to traditional treatments may lead to metastatic disease and/or tumor relapse. Head and neck squamous cell carcinomas (HNSCCs) are the sixth most common malignancy worldwide with the highest incidence occurring in East Asia and eastern and southern Africa. Several cellular subpopulations believed to have CSC properties have been isolated from HNSCCs, but at present, identification and characterization of CSCs remains an experimental challenge with no established or standardized protocols in place to confirm their identity. In this review we discuss current approaches to the study of CSCs with a focus on HNSCCs, particularly in the context of what this might mean from a therapeutic perspective.


Asunto(s)
Neoplasias de Cabeza y Cuello/patología , Células Madre Neoplásicas/citología , Carcinoma de Células Escamosas de Cabeza y Cuello/patología , Neoplasias de Cabeza y Cuello/diagnóstico , Humanos , Metástasis de la Neoplasia , Recurrencia Local de Neoplasia , Carcinoma de Células Escamosas de Cabeza y Cuello/diagnóstico
10.
Int J Mol Sci ; 19(10)2018 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-30249026

RESUMEN

Following exposure of cells to gamma-radiation, a cascade of intracellular consequences may be observed in a semitemporal manner. This includes deoxyribonucleic acid (DNA) damage and reactive oxygen species (ROS) accumulation initially, with consequent signaling for DNA repair and facilitative regulation of the cell cycle. Failure to rectify the damage or ROS levels leads to induction of senescence or apoptosis. 2-Ethyl-3-O-sulfamoyl-estra-1,3,5(10),15-tetraen-17-ol (ESE-15-ol), a 2-methoxyestradiole analog designed in silico for superior pharmacokinetics, was investigated for its potential to enhance apoptotic signaling and decrease the long-term survival of cells exposed to radiation. Sequential early intracellular effects within radiation-treated MCF-7 breast- and A549 lung cancer cells pre-exposed to low-dose ESE-15-ol were investigated using various flow cytometric protocols, spectrophotometry, and microscopy. Long-term cellular survival and proliferation was examined using clonogenic studies, which demonstrated a significant decrease in the presensitized cells. Combination-treated cells exhibited increased superoxide formation, and decreased Bcl-2 expression and -phosphorylation. Induction of apoptosis and elevation of the sub-G1 phase was evident in the pre-exposed MCF-7 cells, although only minimally in the A549 cells at 48-h. These results indicate that low-dose ESE-15-ol may increase tumor response to radiation. Future studies will investigate the effect of ESE-15-ol pre-exposure on radiation-induced DNA damage and repair mechanisms.


Asunto(s)
Apoptosis/efectos de los fármacos , Neoplasias de la Mama/patología , Estradiol/análogos & derivados , Rayos gamma , Neoplasias Pulmonares/patología , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Fármacos Sensibilizantes a Radiaciones/farmacología , Sulfonamidas/farmacología , Apoptosis/efectos de la radiación , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/radioterapia , Ciclo Celular , Daño del ADN , Reparación del ADN , Estradiol/farmacología , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/radioterapia , Fosforilación , Proteínas Proto-Oncogénicas c-bcl-2/genética , Especies Reactivas de Oxígeno/metabolismo , Células Tumorales Cultivadas
11.
Int J Mol Sci ; 19(4)2018 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-29641431

RESUMEN

Deoxyribonucleic acid (DNA) is the self-replicating hereditary material that provides a blueprint which, in collaboration with environmental influences, produces a structural and functional phenotype. As DNA coordinates and directs differentiation, growth, survival, and reproduction, it is responsible for life and the continuation of our species. Genome integrity requires the maintenance of DNA stability for the correct preservation of genetic information. This is facilitated by accurate DNA replication and precise DNA repair. DNA damage may arise from a wide range of both endogenous and exogenous sources but may be repaired through highly specific mechanisms. The most common mechanisms include mismatch, base excision, nucleotide excision, and double-strand DNA (dsDNA) break repair. Concurrent with regulation of the cell cycle, these mechanisms are precisely executed to ensure full restoration of damaged DNA. Failure or inaccuracy in DNA repair contributes to genome instability and loss of genetic information which may lead to mutations resulting in disease or loss of life. A detailed understanding of the mechanisms of DNA damage and its repair provides insight into disease pathogeneses and may facilitate diagnosis and the development of targeted therapies.


Asunto(s)
Daño del ADN , Reparación del ADN , Enfermedades Genéticas Congénitas/genética , Inestabilidad Genómica , Animales , Ciclo Celular/genética , Enfermedades Genéticas Congénitas/terapia , Humanos
12.
Chembiochem ; 18(3): 300-315, 2017 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-27885767

RESUMEN

There is increasing interest in measuring pH in biological samples by using nitroxides with pH-dependent electron paramagnetic resonance (EPR) spectra. Aiming to improve the spectral sensitivity (ΔaX ) of these probes (i.e., the difference between the EPR hyperfine splitting (hfs) in their protonated and unprotonated forms), we characterized a series of novel linear α-carboxy, α'-diethoxyphosphoryl nitroxides constructed on an amino acid core and featuring an (α or α')-C-H bond. In buffer, the three main hfs (aN , aH , and aP ) of their EPR spectra vary reversibly with pH and, from aP or aH titration curves, a two- to fourfold increase in sensitivity was achieved compared to reference imidazoline or imidazolidine nitroxides. The crystallized carboxylate 10 b (pKa ≈3.6), which demonstrated low cytotoxicity and good resistance to bioreduction, was applied to probe stomach acidity in rats. The results pave the way to a novel generation of highly sensitive EPR pH markers.


Asunto(s)
Aminoácidos/química , Espectroscopía de Resonancia por Spin del Electrón , Óxidos de Nitrógeno/química , Organofosfonatos/química , Células A549 , Animales , Supervivencia Celular/efectos de los fármacos , Cristalografía por Rayos X , Ácido Gástrico/química , Mucosa Gástrica/metabolismo , Humanos , Concentración de Iones de Hidrógeno , Espectroscopía de Resonancia Magnética , Masculino , Simulación de Dinámica Molecular , Óxidos de Nitrógeno/toxicidad , Organofosfonatos/síntesis química , Fosforilación , Ratas , Ratas Sprague-Dawley
13.
Environ Sci Technol ; 51(9): 5172-5181, 2017 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-28345896

RESUMEN

Polyethylene (PE), one of the most prominent synthetic polymers used worldwide, is very poorly biodegradable in the natural environment. Consequently, PE represents by itself more than half of all plastic wastes. PE biodegradation is achieved through the combination of abiotic and biotic processes. Several microorganisms have been shown to grow on the surface of PE materials, among which are the species of the Rhodococcus genus, suggesting a potent ability of these microorganisms to use, at least partly, PE as a potent carbon source. However, most of them, if not all, fail to induce a clear-cut degradation of PE samples, showing that bottlenecks to reach optimal biodegradation clearly exist. To identify the pathways involved in PE consumption, we used in the present study a combination of RNA-sequencing and lipidomic strategies. We show that short-term exposure to various forms of PE, displaying different molecular weight distributions and oxidation levels, lead to an increase in the expression of 158 genes in a Rhodococcus representative, R. ruber. Interestingly, one of the most up-regulated pathways is related to alkane degradation and ß-oxidation of fatty acids. This approach also allowed us to identify metabolic limiting steps, which could be fruitfully targeted for optimized PE consumption by R. ruber.


Asunto(s)
Polietileno/metabolismo , Rhodococcus/metabolismo , Secuencia de Bases , Biodegradación Ambiental , Oxidación-Reducción
14.
Environ Sci Technol ; 51(4): 1988-1997, 2017 02 21.
Artículo en Inglés | MEDLINE | ID: mdl-28112955

RESUMEN

With the ever-increasing volume of polymer wastes and their associated detrimental impacts on the environment, the plastic life cycle has drawn increasing attention. Here, eight commercial polymers selected from biodegradable to environmentally persistent materials, all formulated under a credit card format, were incubated in an outdoor compost to evaluate their fate over time and to profile the microbial communities colonizing their surfaces. After 450 days in compost, the samples were all colonized by multispecies biofilms, these latest displaying different amounts of adhered microbial biomass and significantly distinct bacterial and fungal community compositions depending on the substrate. Interestingly, colonization experiments on the eight polymers revealed a large core of shared microbial taxa, predominantly composed of microorganisms previously reported from environments contaminated with petroleum hydrocarbons or plastics debris. These observations suggest that biofilms may contribute to the alteration process of all the polymers studied. Actually, four substrates, independently of their assignment to a polymer group, displayed a significant deterioration, which might be attributed to biologically mediated mechanisms. Relevantly, the deterioration appears strongly associated with the formation of a high-cell density biofilm onto the polymer surfaces. The analysis of various surface properties revealed that roughness and hydrophilicity are likely prominent parameters for driving the biological interactions with the polymers.


Asunto(s)
Biopelículas , Polímeros/química , Plásticos , Suelo , Propiedades de Superficie
15.
Cochrane Database Syst Rev ; (1): CD007037, 2016 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-26820557

RESUMEN

BACKGROUND: Beta-blockers are an essential part of standard therapy in adult congestive heart failure and therefore, are expected to be beneficial in children. However, congestive heart failure in children differs from that in adults in terms of characteristics, aetiology, and drug clearance. Therefore, paediatric needs must be specifically investigated. This is an update of a Cochrane review previously published in 2009. OBJECTIVES: To assess the effect of beta-adrenoceptor-blockers (beta-blockers) in children with congestive heart failure. SEARCH METHODS: We searched the Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library, MEDLINE, EMBASE, and LILACS up to November 2015. Bibliographies of identified studies were checked. No language restrictions were applied. SELECTION CRITERIA: Randomised, controlled, clinical trials investigating the effect of beta-blocker therapy on paediatric congestive heart failure. DATA COLLECTION AND ANALYSIS: Two review authors independently extracted and assessed data from the included trials. MAIN RESULTS: We identified four new studies for the review update; the review now includes seven studies with 420 participants. Four small studies with 20 to 30 children each, and two larger studies of 80 children each, showed an improvement of congestive heart failure with beta-blocker therapy. A larger study with 161 participants showed no evidence of benefit over placebo in a composite measure of heart failure outcomes. The included studies showed no significant difference in mortality or heart transplantation rates between the beta-blocker and control groups. No significant adverse events were reported with beta-blockers, apart from one episode of complete heart block. A meta-analysis of left ventricular ejection fraction (LVEF) and fractional shortening (LVFS) data showed a very small improvement with beta-blockers.However, there were vast differences in the age, age range, and health of the participants (aetiology and severity of heart failure; heterogeneity of diagnoses and co-morbidities); there was a range of treatments across studies (choice of beta-blocker, dosing, duration of treatment); and a lack of standardised methods and outcome measures. Therefore, the primary outcomes could not be pooled in meta-analyses. AUTHORS' CONCLUSIONS: There is not enough evidence to support or discourage the use of beta-blockers in children with congestive heart failure, or to propose a paediatric dosing scheme. However, the sparse data available suggested that children with congestive heart failure might benefit from beta-blocker treatment. Further investigations in clearly defined populations with standardised methodology are required to establish guidelines for therapy. Pharmacokinetic investigations of beta-blockers in children are also required to provide effective dosing in future trials.


Asunto(s)
Antagonistas Adrenérgicos beta/uso terapéutico , Insuficiencia Cardíaca/tratamiento farmacológico , Adolescente , Carbazoles/uso terapéutico , Carvedilol , Niño , Preescolar , Humanos , Lactante , Recién Nacido , Metoprolol/uso terapéutico , Propanolaminas/uso terapéutico , Propranolol/uso terapéutico , Ensayos Clínicos Controlados Aleatorios como Asunto
16.
Biofouling ; 32(3): 287-99, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26905178

RESUMEN

Electromagnetic field (EMF) treatment has proven to be effective against mineral scaling in water systems. Therefore, it should be assessed for the treatment of other deposits such as biofilms. In this study, a commercial device producing low-frequency EMF (1-10 kHz) was applied to a reactor fed with natural water for 45 days. The treatment promoted the concentration of microorganisms in suspension and limited the amount of sessile microorganisms in the biofilm, as determined by the measurement of total DNA, qPCR and microscopy. The structure of the bacterial community was assessed by t-RFLP and pyrosequencing analysis. The results showed that EMF treatment affected both planktonic and sessile community composition. EMFs were responsible for a shift in classes of Proteobacteria during development of the biofilm. It may be speculated that the EMF treatment affected particle solubility and/or microorganism hydration. This study indicated that EMFs modulated biofilm formation in natural water.


Asunto(s)
Biopelículas , Campos Electromagnéticos , Plancton , Proteobacteria , Thoracica , Animales , Biopelículas/crecimiento & desarrollo , Biopelículas/efectos de la radiación , Biota/fisiología , Biota/efectos de la radiación , Plancton/fisiología , Plancton/efectos de la radiación , Proteobacteria/fisiología , Proteobacteria/efectos de la radiación , Thoracica/fisiología , Thoracica/efectos de la radiación
17.
Clin Pharmacol Ther ; 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38961664

RESUMEN

Getting the dose right is a key challenge in drug development; model-informed drug development (MIDD) provides powerful tools to shape dose strategies and inform decision making. In this tutorial, the case study of the ZENITH trials showcases how a set of clinical pharmacology and MIDD approaches informed an impactful dose strategy. The endothelin A receptor antagonist zibotentan, combined with the sodium-glucose co-transporter-2 inhibitor dapagliflozin, has yielded a robust and significant albuminuria reduction in the Phase IIb trial ZENITH-CKD and is being investigated for reduction of kidney function decline in a high-risk chronic kidney disease population in the Phase III trial ZENITH High Proteinuria. Endothelin antagonist treatment has, until now, been limited by the class effect fluid retention. ZENITH-CKD investigated a wide range of zibotentan doses based on pharmacokinetics in renal impairment, competitor-data exposure-response modeling, and clinical trial simulations. Recruitment delays reduced interim analysis data availability; here, supportive dose-response modeling recovered decision-making confidence. At trial completion, the low-dose arm enabled Phase III dose selection between Phase IIb doses. Dose-response modeling of efficacy and Kaplan-Meier analyses of tolerability identified a kidney-function-based low-dose strategy of 0.25 or 0.75 mg zibotentan (with 10 mg dapagliflozin) to balance benefit/risk in ZENITH High Proteinuria. The applied clinical pharmacology and MIDD principles enabled successful Phase IIb dose finding, rationalized and built confidence in the innovative Phase III dosing strategy and identified a potential therapeutic window for zibotentan/dapagliflozin, providing the opportunity for a significant improvement in the treatment of chronic kidney disease with high proteinuria.

18.
Clin Transl Sci ; 17(1): e13703, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-38098144

RESUMEN

The generation of tissue from stem cells is an alluring concept as it holds a number of potential applications in clinical therapeutics and regenerative medicine. Mesenchymal stromal/stem cells (MSCs) can be isolated from a number of different somatic sources, and have the capacity to differentiate into adipogenic, osteogenic, chondrogenic, and myogenic lineages. Although the first three have been extensively investigated, there remains a paucity of literature on the latter. This review looks at the various strategies available in vitro to enhance harvested MSC commitment and differentiation into the myogenic pathway. These include chemical inducers, myogenic-enhancing cell culture substrates, and mechanical and dynamic culturing conditions. Drawing on information from embryonic and postnatal myogenesis from somites, satellite, and myogenic progenitor cells, the mechanisms behind the chemical and mechanical induction strategies can be studied, and the sequential gene and signaling cascades can be used to monitor the progression of myogenic differentiation in the laboratory. Increased understanding of the stimuli and signaling mechanisms in the initial stages of MSC myogenic commitment will provide tools with which we can enhance their differentiation efficacy and advance the process to clinical translation.


Asunto(s)
Células Madre Mesenquimatosas , Humanos , Células Cultivadas , Diferenciación Celular , Técnicas de Cultivo de Célula , Desarrollo de Músculos
19.
Int J Antimicrob Agents ; 63(6): 107166, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38570017

RESUMEN

The demand for antibiofilm molecules has increased over several years due to their potential to fight biofilm-associated infections, such as those including the interkingdom Staphylococcus aureus-Candida albicans occurring in clinical settings worldwide. Recently, we identified a pentacyclic triterpenoid compound, betulinic acid, from invasive macrophytes, with interesting antibiofilm properties. The aim of the present study was to provide insights into the mechanism of action of betulinic acid against the clinically relevant bi-species S. aureus-C. albicans biofilms. Microscopy examinations, flow cytometry and crystal violet assays confirmed that betulinic acid was effective at damaging mature S. aureus-C. albicans biofilms or inhibiting their formation, reducing biofilm biomass by 70% on average and without microbicidal activity. The results suggested an action of betulinic acid on cell membranes, inducing changes in properties such as composition, hydrophobicity and fluidity as observed in C. albicans, which may hinder the early adhesion step, biofilm growth and the physical interactions of both microbial species. Further results of real-time polymerase chain reaction argued in favour of a reduction in S. aureus-C. albicans physical interaction due to betulinic acid by the modulation of biofilm-related gene expression, as observed in early stages of biofilm formation. This study revealed the potential of betulinic acid as a candidate agent for the prevention and treatment of S. aureus-C. albicans biofilm-related infections.


Asunto(s)
Ácido Betulínico , Biopelículas , Candida albicans , Triterpenos Pentacíclicos , Staphylococcus aureus , Triterpenos , Biopelículas/efectos de los fármacos , Triterpenos Pentacíclicos/farmacología , Candida albicans/efectos de los fármacos , Staphylococcus aureus/efectos de los fármacos , Triterpenos/farmacología , Triterpenos/química , Humanos , Citometría de Flujo , Pruebas de Sensibilidad Microbiana , Membrana Celular/efectos de los fármacos , Reacción en Cadena en Tiempo Real de la Polimerasa , Microscopía
20.
Clin Pharmacol Ther ; 116(2): 372-379, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38686600

RESUMEN

The endothelin A receptor antagonist zibotentan, combined with the sodium-glucose co-transporter-2 inhibitor dapagliflozin, is being investigated for the treatment of chronic kidney disease with high proteinuria. To allow women of childbearing potential access to this treatment, highly effective contraception is required and drug interactions compromising contraception reliability must be avoided. This study investigated the risk of pharmacokinetic (PK) interaction between zibotentan and the contraceptives ethinyl estradiol and levonorgestrel. A single-sequence, within-participant comparison study was conducted in 24 healthy women of non-childbearing potential, comparing the PK of ethinyl estradiol/levonorgestrel alone and with zibotentan. Single oral doses of 0.06 mg ethinyl estradiol/0.3 mg levonorgestrel were administered on Days 1 and 15; zibotentan 10 mg was dosed orally, once-daily through Days 6-19. PK profiles were determined and ethinyl estradiol/levonorgestrel PK was compared between Day 1 and 15 based on geometric least-squares mean ratios of PK parameters, including maximum observed concentration (Cmax) and area under the plasma concentration-time curve from zero to infinity (AUCinf). Co-administration with zibotentan did not affect ethinyl estradiol PK (geometric mean ratio [90% confidence interval] Cmax 1.05 [0.99-1.11], AUCinf 1.00 [0.96-1.05]), while a weak interaction (increased exposure) was observed for levonorgestrel (Cmax 1.12 [1.02-1.23], AUCinf 1.30 [1.21-1.39]), which was regarded as without clinical relevance. Plasma exposure of ethinyl estradiol/levonorgestrel was not reduced by multiple-dose zibotentan. In conclusion, contraception containing ethinyl estradiol/levonorgestrel is regarded possible under zibotentan-containing treatments. This expands choices for women of childbearing potential, supporting diversity in the ZENITH High Proteinuria trial.


Asunto(s)
Anticonceptivos Orales Combinados , Interacciones Farmacológicas , Etinilestradiol , Levonorgestrel , Humanos , Femenino , Etinilestradiol/farmacocinética , Etinilestradiol/administración & dosificación , Etinilestradiol/efectos adversos , Levonorgestrel/farmacocinética , Levonorgestrel/administración & dosificación , Levonorgestrel/efectos adversos , Adulto , Adulto Joven , Anticonceptivos Orales Combinados/farmacocinética , Anticonceptivos Orales Combinados/administración & dosificación , Combinación de Medicamentos , Antagonistas de los Receptores de la Endotelina A/farmacocinética , Antagonistas de los Receptores de la Endotelina A/administración & dosificación , Área Bajo la Curva
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