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1.
Mol Cell Biochem ; 478(11): 2517-2526, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36867341

RESUMEN

The severe acute respiratory coronavirus 2 (SARS-CoV-2) infection demonstrates a highly variable and unpredictable course. Several reports have claimed a smoker's paradox in coronavirus disease 2019 (COVID-19), in line with previous suggestions that smoking is associated with better survival after acute myocardial infarction and appears protective in preeclampsia. Several plausible physiological explanations exist accounting for the paradoxical observation of smoking engendering protection against SARS-CoV-2 infection. In this review, we delineate novel mechanisms whereby smoking habits and smokers' genetic polymorphism status affecting various nitric oxide (NO) pathways (endothelial NO synthase, cytochrome P450 (CYP450), erythropoietin receptor (EPOR); ß-common receptor (ßcR)), along with tobacco smoke modulation of microRNA-155 and aryl-hydrocarbon receptor (AHR) effects, may be important determinators of SARS-CoV-2 infection and COVID-19 course. While transient NO bioavailability increase and beneficial immunoregulatory modulations through the above-mentioned pathways using exogenous, endogenous, genetic and/or therapeutic modalities may have direct and specific, viricidal SARS-CoV-2 effects, employing tobacco smoke inhalation to achieve protection equals self-harm. Tobacco smoking remains the leading cause of death, illness, and impoverishment.

2.
Br J Cancer ; 117(11): 1592-1599, 2017 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-28972963

RESUMEN

BACKGROUND: ARQ 087 is an orally administered pan-FGFR inhibitor with multi-kinase activity. This Phase 1 study evaluated safety, pharmacokinetics, and pharmacodynamics of ARQ 087 and defined the recommended Phase 2 dose (RP2D). METHODS: Patients with advanced solid tumours received ARQ 087 administered initially at 25 mg every other day and dose-escalated from 25 to 425 mg daily (QD) continuous dosing. FGF19, 21, 23, and serum phosphate were assessed as potential biomarkers of target engagement. RESULTS: 80 patients were enrolled, 61 in dose-escalation/food-effect cohorts and 19 with pre-defined tumour types in the expansion cohort. The most common ARQ 087-related adverse events were fatigue (49%), nausea (46%), aspartate aminotransferase (AST) increase (30%), and diarrhoea (23%). Four patients (5%) experienced grade 1 treatment-related hyperphosphataemia. Dose-limiting toxicity was reversible grade 3 AST increase. The RP2D was 300 mg QD. Pharmacokinetics were linear and dose-proportional from 25 to 325 mg QD, and were unaffected by food. Statistically significant changes (P-value<0.05) suggest phosphate and FGF19 levels as markers of target engagement. In 18 evaluable patients with FGFR genetic alterations, 3 confirmed partial responses (two intrahepatic cholangiocarcinomas (iCCA) with FGFR2 fusions and one urothelial cancer with FGFR2 and FGF19 amplification) and two durable stable disease at ⩾16 weeks with tumour reduction (FGFR2 fusion-positive iCCA and adrenocortical carcinoma with FGFR1 amplification) were observed. CONCLUSIONS: ARQ 087 had manageable toxicity at the RP2D of 300 mg QD, showed pharmacodynamics effects, and achieved objective responses, notably in patients with FGFR2 genetic alterations.


Asunto(s)
Compuestos de Anilina/uso terapéutico , Neoplasias/tratamiento farmacológico , Inhibidores de Proteínas Quinasas/uso terapéutico , Quinazolinas/uso terapéutico , Receptores de Factores de Crecimiento de Fibroblastos/antagonistas & inhibidores , Administración Oral , Adulto , Anciano , Compuestos de Anilina/efectos adversos , Compuestos de Anilina/farmacocinética , Femenino , Humanos , Masculino , Persona de Mediana Edad , Quinazolinas/efectos adversos , Quinazolinas/farmacocinética , Receptores de Factores de Crecimiento de Fibroblastos/genética
3.
Ann Oncol ; 27(3): 526-32, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26646757

RESUMEN

BACKGROUND: Fibroblast growth factors (FGFs) play important roles in multiple cancers by supporting tumor growth and angiogenesis. FP-1039 (GSK3052230) is a FGF ligand trap consisting of the extracellular domain of FGF receptor 1 (FGFR1) fused with the Fc region of IgG1. FP-1039 binds and neutralizes multiple FGFs that normally bind FGFR1. The primary objective of this phase I study was to evaluate the safety and tolerability of FP-1039. PATIENTS AND METHODS: Eligible patients with metastatic or locally advanced solid tumors for which standard treatments were ineffective were treated with weekly doses of FP-1039 for 4 weeks, followed by 2 weeks observation. RESULTS: Thirty-nine subjects received a mean of 6 infusions of FP-1039 at doses ranging from 0.5 to 16 mg/kg weekly, with no maximally tolerated dose identified. Grade 3 or greater treatment emergent adverse events were uncommon. Four dose-limiting toxicities were reported at doses of 0.75 mg/kg (urticaria), 1 mg/kg (intestinal perforation and neutropenia), and 16 mg/kg (muscular weakness). Drug exposure was dose proportional, and the terminal elimination half-life was 2.6-3.9 days following a single dose. Target engagement as measured by low free plasma FGF2 levels was achieved. FGF pathway dysregulation was uncommon. No objective responses were observed. CONCLUSION: In nonselected cancer patients with advanced disease, treatment with FP-1039 was well tolerated and toxicities associated with small molecule drugs that inhibit FGFR tyrosine kinases, including hyperphosphatemia, were not observed. Further studies of FP-1039 in patients selected for FGF pathway dysregulation, who are most likely to benefit, are now underway.


Asunto(s)
Antineoplásicos/uso terapéutico , Factores de Crecimiento de Fibroblastos/antagonistas & inhibidores , Inmunoglobulina G/uso terapéutico , Neoplasias/tratamiento farmacológico , Proteínas de Fusión Oncogénica/uso terapéutico , Receptor Tipo 1 de Factor de Crecimiento de Fibroblastos/uso terapéutico , Adulto , Anciano , Antineoplásicos/efectos adversos , Antineoplásicos/farmacocinética , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Femenino , Factores de Crecimiento de Fibroblastos/metabolismo , Humanos , Inmunoglobulina G/efectos adversos , Masculino , Dosis Máxima Tolerada , Persona de Mediana Edad , Proteínas de Fusión Oncogénica/efectos adversos , Proteínas de Fusión Oncogénica/farmacocinética , Receptor Tipo 1 de Factor de Crecimiento de Fibroblastos/metabolismo , Proteínas Recombinantes de Fusión
4.
Ann Oncol ; 27(10): 1928-40, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27672108

RESUMEN

BACKGROUND: To evaluate the safety, tolerability, pharmacokinetics, and maximum tolerated dose (MTD) of copanlisib, a phosphatidylinositol 3-kinase inhibitor, in patients with advanced solid tumors or non-Hodgkin's lymphoma (NHL). PATIENTS AND METHODS: Phase I dose-escalation study including patients with advanced solid tumors or NHL, and a cohort of patients with type 2 diabetes mellitus. Patients received three weekly intravenous infusions of copanlisib per 28-day cycle over the dose range 0.1-1.2 mg/kg. Plasma copanlisib levels were analyzed for pharmacokinetics. Biomarker analysis included PIK3CA, KRAS, BRAF, and PTEN mutational status and PTEN immunohistochemistry. Whole-body [(18)F]-fluorodeoxyglucose positron emission tomography ((18)FDG-PET) was carried out at baseline and following the first dose to assess early pharmacodynamic effects. Plasma glucose and insulin levels were evaluated serially. RESULTS: Fifty-seven patients received treatment. The MTD was 0.8 mg/kg copanlisib. The most frequent treatment-related adverse events were nausea and transient hyperglycemia. Copanlisib exposure was dose-proportional with no accumulation; peak exposure positively correlated with transient hyperglycemia post-infusion. Sixteen of 20 patients treated at the MTD had reduced (18)FDG-PET uptake; 7 (33%) had a reduction >25%. One patient achieved a complete response (CR; endometrial carcinoma exhibiting both PIK3CA and PTEN mutations and complete PTEN loss) and two had a partial response (PR; both metastatic breast cancer). Among the nine NHL patients, all six with follicular lymphoma (FL) responded (one CR and five PRs) and one patient with diffuse large B-cell lymphoma had a PR by investigator assessment; two patients with FL who achieved CR (per post hoc independent radiologic review) were on treatment >3 years. CONCLUSION: Copanlisib, dosed intermittently on days 1, 8, and 15 of a 28-day cycle, was well tolerated and the MTD was determined to be 0.8 mg/kg. Copanlisib exhibited dose-proportional pharmacokinetics and promising anti-tumor activity, particularly in patients with NHL. CLINICALTRIALSGOV: NCT00962611; https://clinicaltrials.gov/ct2/show/NCT00962611.


Asunto(s)
Fosfatidilinositol 3-Quinasa Clase I/antagonistas & inhibidores , Inhibidores Enzimáticos/administración & dosificación , Linfoma no Hodgkin/tratamiento farmacológico , Neoplasias/tratamiento farmacológico , Pirimidinas/administración & dosificación , Quinazolinas/administración & dosificación , Administración Intravenosa , Adulto , Anciano , Fosfatidilinositol 3-Quinasa Clase I/genética , Relación Dosis-Respuesta a Droga , Inhibidores Enzimáticos/efectos adversos , Inhibidores Enzimáticos/farmacocinética , Femenino , Humanos , Linfoma no Hodgkin/enzimología , Linfoma no Hodgkin/patología , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Neoplasias/enzimología , Neoplasias/patología , Pirimidinas/efectos adversos , Pirimidinas/farmacocinética , Quinazolinas/efectos adversos , Quinazolinas/farmacocinética
5.
Lasers Med Sci ; 31(3): 459-69, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26796709

RESUMEN

This study aimed to compare the effectiveness of the combined low-level laser therapy (LLLT) and passive stretching with combined placebo LLLT laser and the same passive stretching exercises in patients suffering from Αnkylosing spondylitis. Forty-eight patients suffering from Αnkylosing spondylitis participated in the study and were randomized into two groups. Group A (n = 24) was treated with a λ = 820 Ga-Al-As laser CW, with power intensity = 60 mW/cm(2), energy per point in each session = 4.5 J, total energy per session = 27.0 J, in contact with specific points technique, plus passive stretching exercises. Group B (n = 24), received placebo laser plus the same passive stretching exercises. Both groups received 12 sessions of laser or placebo within 8 weeks; two sessions per week (weeks 1-4) and one session per week (weeks 5-8). Pain and function scales were completed before the treatment, at the end of the fourth and eighth week of treatment, and 8 weeks after the end of treatment (follow-up). Group A revealed a significant improvement after 8 weeks of treatment in all pain and function scales. At 8-week follow-up, the improvement remained only for the pain, while for all other function outcomes the differences were not statistically significant. The results suggested that after an 8-week treatment and after a follow-up, the combination of LLLT and passive stretching exercises decreased pain more effectively than placebo LLLT along with the same passive stretching exercises in patients with Αnkylosing spondylitis. Future studies are needed to establish the relative and absolute effectiveness of the above protocol.


Asunto(s)
Artralgia/radioterapia , Terapia por Luz de Baja Intensidad , Espondilitis Anquilosante/radioterapia , Adulto , Terapia Combinada , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Ejercicios de Estiramiento Muscular , Resultado del Tratamiento
6.
Ann Oncol ; 26(1): 58-64, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25344362

RESUMEN

BACKGROUND: This phase Ib trial investigated the safety, tolerability, and recommended phase II dose and schedule of the MEK inhibitor trametinib in combination with the mammalian target of rapamycin (mTOR) inhibitor everolimus. Secondary objectives included pharmacokinetic (PK) characterization and evaluation of clinical activity. PATIENTS AND METHODS: A total of 67 patients with advanced solid tumors were enrolled in this open-label, single-arm, dose-escalation study. Dose escalation followed a 3 + 3 design. Patients were assigned to one of 10 different cohorts, involving either daily dosing with both agents or daily dosing with trametinib and intermittent everolimus dosing. This included an expansion cohort comprising patients with pancreatic tumors. PKs samples were collected predose, as well as 1, 2, 4, and 6 h post-dose on day 15 of the first treatment cycle. RESULTS: Concurrent treatment with trametinib and everolimus resulted in frequent treatment-related adverse events, including mucosal inflammation (40%), stomatitis (25%), fatigue (54%), and diarrhea (42%). PK assessment did not suggest drug-drug interactions between these two agents. Of the 67 enrolled patients, 5 (7%) achieved partial response (PR) to treatment and 21 (31%) displayed stable disease (SD). Among the 21 patients with pancreatic cancer, PR was observed in 1 patient (5%) and SD in 6 patients (29%). CONCLUSIONS: This study was unable to identify a recommended phase II dose and schedule of trametinib in combination with everolimus that provided an acceptable tolerability and adequate drug exposure.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias/tratamiento farmacológico , Inhibidores de Proteínas Quinasas/uso terapéutico , Piridonas/uso terapéutico , Pirimidinonas/uso terapéutico , Sirolimus/análogos & derivados , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/farmacocinética , Esquema de Medicación , Everolimus , Femenino , Humanos , MAP Quinasa Quinasa 1/antagonistas & inhibidores , MAP Quinasa Quinasa 2/antagonistas & inhibidores , Masculino , Persona de Mediana Edad , Inhibidores de Proteínas Quinasas/efectos adversos , Inhibidores de Proteínas Quinasas/farmacocinética , Piridonas/efectos adversos , Piridonas/farmacocinética , Pirimidinonas/efectos adversos , Pirimidinonas/farmacocinética , Sirolimus/efectos adversos , Sirolimus/farmacocinética , Sirolimus/uso terapéutico , Serina-Treonina Quinasas TOR/antagonistas & inhibidores , Resultado del Tratamiento , Adulto Joven
7.
Br J Cancer ; 111(2): 272-80, 2014 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-24901237

RESUMEN

BACKGROUND: Ficlatuzumab, a humanised hepatocyte growth factor (HGF) IgG1κ inhibitory monoclonal antibody, was evaluated for recommended phase II dose (RP2D), safety, pharmacokinetics (PKs), antidrug antibody (ADA), pharmacodynamics (PDs) and antitumour activity as monotherapy or combined with erlotinib. METHODS: Patients with solid tumours received ficlatuzumab 2, 5, 10 or 20 mg kg(-1) intravenously every 2 weeks (q2w). Additional patients were treated at the RP2D erlotinib. RESULTS: Forty-one patients enrolled at doses ⩽20 mg kg(-1). Common adverse events (AEs) included peripheral oedema, fatigue and nausea. Three patients experienced grade ⩾3 treatment-related hyperkalaemia/hypokalaemia, diarrhoea or fatigue. Best overall response (44%) was stable disease (SD); median duration was 5.5 months (0.4-18.7 months). One patient has been on therapy with SD for >4 years. Pharmacokinetics of ficlatuzumab showed low clearance (0.17-0.26 ml h(-1) kg(-1)), a half-life of 6.8-9.4 days and dose-proportional exposure. Ficlatuzumab/erlotinib had no impact on the PK of either agent. No ADAs were detected. Ficlatuzumab increased serum HGF levels. CONCLUSIONS: Recommended phase II dose is 20 mg kg(-1) q2w for ficlatuzumab monotherapy or with erlotinib. Preliminary antitumour activity and manageable AEs were observed. Pharmacokinetics were dose-proportional and consistent with other IgG therapeutics. Ficlatuzumab was not immunogenic, and serum HGF was a potential PD marker.


Asunto(s)
Anticuerpos Monoclonales/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Mieloma Múltiple/tratamiento farmacológico , Neoplasias/tratamiento farmacológico , Adulto , Anciano , Anciano de 80 o más Años , Anticuerpos Monoclonales/administración & dosificación , Anticuerpos Monoclonales/efectos adversos , Anticuerpos Monoclonales/farmacocinética , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/farmacocinética , Estudios de Cohortes , Clorhidrato de Erlotinib , Femenino , Humanos , Masculino , Persona de Mediana Edad , Mieloma Múltiple/metabolismo , Mieloma Múltiple/patología , Neoplasias/metabolismo , Neoplasias/patología , Inhibidores de Proteínas Quinasas/administración & dosificación , Inhibidores de Proteínas Quinasas/farmacocinética , Quinazolinas/administración & dosificación , Quinazolinas/efectos adversos , Quinazolinas/farmacocinética
8.
Hum Cell ; 37(3): 582-592, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38472734

RESUMEN

AXL is the gene that encodes the Anexelekto (AXL) receptor tyrosine kinase that demonstrates significant roles in various cellular processes, including cell growth, survival, and migration. Anexelekto is a Greek word meaning excessive and uncontrolled, semantically implying the crucial involvement of AXL in cancer and immune biology, and in promoting cancer metastasis. AXL overexpression appears to drive epithelial to mesenchymal transition, tumor angiogenesis, decreased antitumor immune response, and resistance to therapeutic agents. Recently, AXL has been reported to play important roles in several viral infections, including SARS-CoV-2. We have previously outlined the importance of microRNAs (miRNAs, miRs) and especially miR-155 in SARS-CoV-2 pathophysiology through regulation of the Renin-Angiotensin Aldosterone System (RAAS) and influence on several aspects of host innate immunity. MiRNAs are negative regulators of gene expression, decreasing the stability of target RNAs or limiting their translation and, enthrallingly, miR-155 is also involved in AXL homeostasis-both endogenously and pharmaceutically using repurposed drugs (e.g., metformin)-highlighting thrifty evolutionary host innate immunity mechanisms that successfully can thwart viral entry and replication. Cancer, infections, and immune system disturbances will increasingly involve miRNA diagnostics and therapeutics in the future.


Asunto(s)
COVID-19 , MicroARNs , Neoplasias , Humanos , SARS-CoV-2/metabolismo , Tirosina Quinasa del Receptor Axl , Proteínas Proto-Oncogénicas/genética , Transición Epitelial-Mesenquimal/genética , COVID-19/genética , MicroARNs/genética
9.
Perfusion ; 28(2): 160-6, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23257679

RESUMEN

BACKGROUND: Given that micelles of lipids are colloids, the hypothesis was generated that the rapid administration of large volumes of soybean oil micelles would be an effective perfusion fluid. We also hypothesized that oxygen loading would be enhanced due to the greater solubility of oxygen in lipids compared to water. METHODS: A 100% lethal mouse model of blood loss was used to compare the ability of soybean oil micelles to that of Ringer's lactate, blood and other fluids, with respect to raising and maintaining the blood pressure for one hour. Oxygen on- and off-loading of various concentrations of soybean oil micelles was determined using mass spectroscopy. Nitric oxide uptake by micelles was also determined in a similar fashion. RESULTS: A 20% soybean oil emulsion was superior to Ringer's lactate in raising and maintaining blood pressure. A 20% soybean oil emulsion with 5% albumin added was superior to shed blood as well as solutions comprised of 5% albumin added to either normal saline or Ringer's lactate. There was a linear relationship between oxygen content and micelle concentration between 10% and 30%. Off-loading of oxygen from the micelles was nearly as fast as off-loading from water. Nitric oxide also loaded preferentially onto soybean oil micelles. CONCLUSIONS: (1) Soybean oil emulsions were superior to other fluids in restoring and maintaining the blood pressure; (2) oxygen-carrying ability of soybean oil micelles exceeds that of water and follows Henry's law between 10% and 30% w/v oil content; (3) nitric oxide was carried by the micelles; (4) animals receiving soybean oil micelles did not exhibit fat embolization; (5) colloids comprised of soybean oil-containing micelles may be used to replace blood loss and may be used to deliver oxygen and other potentially therapeutic gases such as nitric oxide to tissues.


Asunto(s)
Emulsiones Grasas Intravenosas , Micelas , Oxígeno/sangre , Choque Hemorrágico/sangre , Choque Hemorrágico/tratamiento farmacológico , Aceite de Soja , Animales , Presión Sanguínea/efectos de los fármacos , Modelos Animales de Enfermedad , Emulsiones Grasas Intravenosas/química , Emulsiones Grasas Intravenosas/farmacocinética , Emulsiones Grasas Intravenosas/farmacología , Ratones , Óxido Nítrico/sangre , Choque Hemorrágico/fisiopatología , Aceite de Soja/química , Aceite de Soja/farmacocinética , Aceite de Soja/farmacología
10.
Hum Cell ; 36(3): 908-922, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36847920

RESUMEN

Severe acute respiratory coronavirus 2 (SARS-CoV-2) infection in the young and healthy usually results in an asymptomatic or mild viral syndrome, possibly through an erythropoietin (EPO)-dependent, protective evolutionary landscape. In the old and in the presence of co-morbidities, however, a potentially lethal coronavirus disease 2019 (COVID-19) cytokine storm, through unrestrained renin-angiotensin aldosterone system (RAAS) hyperactivity, has been described. Multifunctional microRNA-155 (miR-155) elevation in malaria, dengue virus (DENV), the thalassemias, and SARS-CoV-1/2, plays critical antiviral and cardiovascular roles through its targeted translational repression of over 140 genes. In the present review, we propose a plausible miR-155-dependent mechanism whereby the translational repression of AGRT1, Arginase-2 and Ets-1, reshapes RAAS towards Angiotensin II (Ang II) type 2 (AT2R)-mediated balanced, tolerable, and SARS-CoV-2-protective cardiovascular phenotypes. In addition, it enhances EPO secretion and endothelial nitric oxide synthase activation and substrate availability, and negates proinflammatory Ang II effects. Disrupted miR-155 repression of AT1R + 1166C-allele, significantly associated with adverse cardiovascular and COVID-19 outcomes, manifests its decisive role in RAAS modulation. BACH1 and SOCS1 repression creates an anti-inflammatory and cytoprotective milieu, robustly inducing antiviral interferons. MiR-155 dysregulation in the elderly, and in comorbidities, allows unimpeded RAAS hyperactivity to progress towards a particularly aggressive COVID-19 course. Elevated miR-155 in thalassemia plausibly engenders a favorable cardiovascular profile and protection against malaria, DENV, and SARS-CoV-2. MiR-155 modulating pharmaceutical approaches could offer novel therapeutic options in COVID-19.


Asunto(s)
COVID-19 , MicroARNs , Humanos , SARS-CoV-2 , COVID-19/genética , Peptidil-Dipeptidasa A , Angiotensina II , Antivirales , MicroARNs/genética
11.
J Chem Phys ; 137(17): 174501, 2012 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-23145733

RESUMEN

Molecular dynamics simulations are obtained and analyzed to study pairing of 1-hexyl-3-methylimidazolium and tetrafluoroborate ions in n-pentanol, in particular by evaluating the potential-of-mean-force between counter ions. The present molecular model and simulation accurately predicts the dissociation constant K(d) in comparison to experiment, and thus the behavior and magnitudes for the ion-pair potential-of-mean-force at molecular distances, even though the dielectric constant of the simulated solvent differs from the experimental value by about 30%. A naive dielectric model does not capture molecule structural effects such as multiple conformations and binding geometries of the Hmim(+) and BF(4)(-) ion-pairs. Mobilities identify multiple time-scale effects in the autocorrelation of the random forces on the ions, and specifically a slow, exponential time-decay of those long-ranged forces associated here with dielectric friction effects.

12.
Br J Cancer ; 105(7): 938-44, 2011 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-21878940

RESUMEN

BACKGROUND: To evaluate the anticancer activity of erlotinib in patients with previously treated, advanced non-small cell lung cancer (NSCLC) whose dose is increased to that associated with a maximal level of tolerable skin toxicity (i.e., target rash (TR)); to characterise the pharmacokinetics (PK) and pharmacodynamics (PD) of higher doses of erlotinib. METHODS: Patients initially received erlotinib 150 mg per day. The dose was successively increased in each patient to that associated with a TR. Anticancer activity was evaluated. Plasma, skin, and hair were sampled for PK and PD studies. RESULTS: Erlotinib dose escalation to 200-475 mg per day was feasible in 38 (90%) of 42 patients. Twenty-four (57%) patients developed a TR, but 19 (79%) did so at 150 mg per day. Five (12%) patients, all of whom developed a TR, had a partial response. Median progression-free survival (PFS) was 2.3 months (95% CI: 1.61, 4.14); median PFS was 3.5 months and 1.9 months, respectively, for patients who did and did not experience a TR (hazard ratio, 0.51; P=0.051). Neither rash severity nor response correlated with erlotinib exposure. CONCLUSION: Intrapatient dose escalation of erlotinib does not appreciably increase the propensity to experience a maximal level of tolerable skin toxicity, or appear to increase the anticancer activity of erlotinib in NSCLC.


Asunto(s)
Adenocarcinoma/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Células Escamosas/tratamiento farmacológico , Exantema/inducido químicamente , Neoplasias Pulmonares/tratamiento farmacológico , Inhibidores de Proteínas Quinasas/uso terapéutico , Quinazolinas/uso terapéutico , Adenocarcinoma/patología , Adulto , Anciano , Carcinoma de Pulmón de Células no Pequeñas/patología , Carcinoma de Células Escamosas/patología , Clorhidrato de Erlotinib , Femenino , Humanos , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad , Pronóstico , Inhibidores de Proteínas Quinasas/farmacocinética , Quinazolinas/farmacocinética , Distribución Tisular
13.
J Chem Phys ; 134(5): 054502, 2011 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-21303133

RESUMEN

An elementary statistical observation identifies generalizations of the Fuoss approximation for the probability distribution function that describes ion clustering in electrolyte solutions. The simplest generalization, equivalent to a Poisson distribution model for inner-shell occupancy, exploits measurable interionic correlation functions, and is correct at the closest pair distances whether primitive electrolyte solutions models or molecularly detailed models are considered, and for low electrolyte concentrations in all cases. With detailed models, these generalizations include nonionic interactions and solvation effects. These generalizations are relevant for computational analysis of bimolecular reactive processes in solution. Comparisons with direct numerical simulation results show that the simplest generalization is accurate for a slightly supersaturated solution of tetraethylammonium tetrafluoroborate in propylene carbonate ([tea][BF(4)]/PC), and also for a primitive model associated with the [tea][BF(4)]/PC results. For [tea][BF(4)]/PC, the atomically detailed results identify solvent-separated nearest-neighbor ion-pairs. This generalization is examined also for the ionic liquid 1-butyl-3-methylimidazolium tetrafluoroborate ([bmim][BF(4)]) where the simplest implementation is less accurate. In this more challenging situation an augmented maximum entropy procedure is satisfactory, and explains the more varied near-neighbor distributions observed in that case.

17.
Rev Sci Instrum ; 90(8): 083505, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31472640

RESUMEN

Whistler and Alfvén waves are known to scatter mirror-trapped electrons and protons into the loss cone of the earth's dipole magnetic field. An array of satellites with properly phased antennas can be used to artificially reduce the flux of energetic particles from regions where their flux has been naturally or artificially pumped. In any space based system, the power required to drive antennas is at a premium. We present here experimental evidence that the efficiency of an antenna can be greatly enhanced with the use of ferrite cores with high relative magnetic permeability µ. Ferrite-based antennas were constructed to launch Alfvén waves in a magnetized plasma. The wave magnetic field of shear Alfvén waves launched with a ferrite core was by the magnetization factor µ larger than that of a similar antenna without a ferrite. Combining multiple ferrite antennas allowed control of the injected perpendicular wavelength. This novel technique can be used to efficiently launch low frequency waves with amplitude above the threshold required for nonlinear triggering.

18.
Open Cardiovasc Med J ; 11: 28-32, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28567131

RESUMEN

OBJECTIVES: To evaluate the usefulness of the SYNTAX score (SS) in predicting 1-year clinical outcomes in a population of patients with chronic coronary artery disease (CAD) undergoing percutaneous coronary intervention (PCI) or coronary artery bypass grafting (CABG). BACKGROUND: Despite the proven prognostic value of the SS in patients with multivessel and/or left main (LM) CAD, its usefulness in other patient subsets remains uncertain. METHODS: This was a prospective single centre cohort study conducted from September 2012 to November 2014 at the Nicosia General Hospital, Cyprus. Patients (n=140; 94% men and 6% women) with chronic CAD undergoing revascularization with either PCI or CABG were evaluated. RESULTS: At 1-year, angina occurred in 20 patients (14.3%), myocardial infarction (MI) in 3 patients (2.1%), repeat revascularization procedures in 9 patients (6.4%) and death in 12 patients (8.6%). The SS independently predicted angina (p=0.024) but was not predictive of MI (p=0.964), death (p=0.292) or repeat revascularization (p=0.069). CONCLUSION: In this patient population, the SS predicted angina in the year following revascularization but was not predictive of MI, death or repeat revascularization.

19.
Diabetes ; 45(12): 1761-5, 1996 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8922363

RESUMEN

The process of beta-cell destruction in IDDM is mediated, in part, by CD8+ T-cells. Structural characterization of HLA-I-bound self-peptides presented by the human beta-cell line HP-62 was performed to identify possible tissue-specific autoantigens in the context of CD8+ T-cell/HLA-I interactions. The sequences of the beta-cell line HLA-I-bound peptides were compared with sequence databases. Six of the obtained sequences showed homology to known precursor proteins, three of which--GLUT2 receptor, phosphatidylinositol-glycan-specific phospholipase D, and 5-hydroxytryptamine-1F receptor--have a limited, tissue-specific expression. These HLA-bound self-peptides may be part of a pool of autoantigens recognized by beta-cell reactive cytotoxic T-cells.


Asunto(s)
Autoantígenos/inmunología , Antígenos de Histocompatibilidad Clase I/metabolismo , Islotes Pancreáticos/inmunología , Péptidos/inmunología , Secuencia de Aminoácidos , Linfocitos T CD8-positivos/inmunología , Línea Celular , Transportador de Glucosa de Tipo 2 , Humanos , Proteínas de Transporte de Monosacáridos/química , Proteínas de Transporte de Monosacáridos/inmunología , Fragmentos de Péptidos/química , Fragmentos de Péptidos/inmunología , Péptidos/química , Fosfolipasa D/química , Fosfolipasa D/inmunología , Precursores de Proteínas/inmunología , Receptores de Serotonina/química , Receptores de Serotonina/inmunología
20.
Bone Marrow Transplant ; 36(6): 491-7, 2005 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16044139

RESUMEN

In an effort to improve the outcome of poor-risk lymphoma patients, we evaluated a novel regimen of tandem high-dose chemotherapy (THDC) with autologous stem cell transplantation. A total of 41 patients (median age 40 years, range 15-68 years) with poor-risk non-Hodgkin's lymphoma and Hodgkin's disease were enrolled. THDC consisted of melphalan (180 mg/m2) and escalating dose mitoxantrone (30-50 mg/m2) (MMt) for the first conditioning regimen, and thiotepa (500 mg/m2), carboplatin (800 mg/m2), and escalating dose etoposide phosphate (400-850 mg/m2), (ETCb) as the second regimen. In all, 31 patients (76%) completed both transplants, with a median time between transplants of 55 days (range 26-120). The maximum tolerated dose was determined as 40 mg/m2 for mitoxantrone and 550 mg/m2 for etoposide phosphate. The overall toxic death rate was 12%. Following high-dose chemotherapy, 10 of 24 evaluable patients (42%) were in CR. The two-year overall survival and event-free survival is 67% (95% CI, 52-81%) and 45%, (95% CI, 29-61%) for the 41 patients enrolled; and 69% (95% CI, 525-586%) and 48% (95% CI, 30-67%) for the 31 patients completing both transplants. This THDC regimen is feasible but with notable toxicity in heavily pretreated patients; its role in the current treatment of high-risk lymphoma remains to be determined.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Trasplante de Células Madre Hematopoyéticas/métodos , Linfoma/terapia , Adolescente , Adulto , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/toxicidad , Femenino , Trasplante de Células Madre Hematopoyéticas/mortalidad , Humanos , Linfoma/complicaciones , Linfoma/mortalidad , Masculino , Dosis Máxima Tolerada , Melfalán/administración & dosificación , Persona de Mediana Edad , Mitoxantrona/administración & dosificación , Proyectos Piloto , Riesgo , Análisis de Supervivencia , Acondicionamiento Pretrasplante/métodos , Trasplante Autólogo
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