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1.
Int J Mol Sci ; 25(11)2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38892246

RESUMEN

This ABIGENE pharmacokinetic (PK) study sought mainly to characterize the unchanged drug PK during long-term abiraterone acetate (AA) administration in advanced prostate cancer patients (81 patients). It was observed that individual AA concentrations remained constant over treatment time, with no noticeable changes during repeated long-term drug administration for up to 120 days. There was no correlation between AA concentrations and survival outcomes. However, a significant association between higher AA concentrations and better clinical benefit was observed (p = 0.041). The safety data did not correlate with the AA PK data. A significant positive correlation (r = 0.40, p < 0.001) was observed between mean AA concentration and patient age: the older the patient, the higher the AA concentration. Patient age was found to impact steady-state AA concentration: the older the patient, the higher the mean AA concentration. Altogether, these data may help to guide future research and clinical trials in order to maximize the benefits of AA metastatic castration-resistant prostate cancer patients.


Asunto(s)
Acetato de Abiraterona , Neoplasias de la Próstata Resistentes a la Castración , Humanos , Masculino , Acetato de Abiraterona/farmacocinética , Acetato de Abiraterona/uso terapéutico , Acetato de Abiraterona/administración & dosificación , Neoplasias de la Próstata Resistentes a la Castración/tratamiento farmacológico , Neoplasias de la Próstata Resistentes a la Castración/patología , Anciano , Persona de Mediana Edad , Anciano de 80 o más Años , Estudios de Seguimiento , Metástasis de la Neoplasia , Antineoplásicos/farmacocinética , Antineoplásicos/uso terapéutico , Antineoplásicos/administración & dosificación
2.
Mol Oncol ; 18(7): 1719-1738, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38214418

RESUMEN

Metformin and IACS-010759 are two distinct antimetabolic agents. Metformin, an established antidiabetic drug, mildly inhibits mitochondrial complex I, while IACS-010759 is a new potent mitochondrial complex I inhibitor. Mitochondria is pivotal in the energy metabolism of cells by providing adenosine triphosphate through oxidative phosphorylation (OXPHOS). Hence, mitochondrial metabolism and OXPHOS become a vulnerability when targeted in cancer cells. Both drugs have promising antitumoral effects in diverse cancers, supported by preclinical in vitro and in vivo studies. We present evidence of their direct impact on cancer cells and their immunomodulatory effects. In clinical studies, while observational epidemiologic studies on metformin were encouraging, actual trial results were not as expected. However, IACS-01075 exhibited major adverse effects, thereby causing a metabolic shift to glycolysis and elevated lactic acid concentrations. Therefore, the future outlook for these two drugs depends on preventive clinical trials for metformin and investigations into the plausible toxic effects on normal cells for IACS-01075.


Asunto(s)
Complejo I de Transporte de Electrón , Metformina , Neoplasias , Metformina/uso terapéutico , Metformina/farmacología , Humanos , Neoplasias/tratamiento farmacológico , Neoplasias/metabolismo , Neoplasias/inmunología , Complejo I de Transporte de Electrón/metabolismo , Complejo I de Transporte de Electrón/antagonistas & inhibidores , Animales , Antineoplásicos/uso terapéutico , Antineoplásicos/farmacología , Fosforilación Oxidativa/efectos de los fármacos
3.
Rev Esp Cardiol (Engl Ed) ; 77(2): 150-157, 2024 Feb.
Artículo en Inglés, Español | MEDLINE | ID: mdl-37879431

RESUMEN

INTRODUCTION AND OBJECTIVES: The optimal antithrombotic strategy following left atrial appendage closure (LAAC) is poorly defined in patients with nonvalvular atrial fibrillation. We assessed the safety and effectiveness of a single antiplatelet treatment (SAPT) strategy after LAAC in a population at high risk of ischemic and bleeding events. METHODS: This single-center, observational, prospective study included a consecutive cohort of patients who underwent LAAC using the LAmbre device (Lifetech Scientific, China) and who were discharged with SAPT. The primary outcome was a composite of stroke, systemic embolism, and device-related thrombosis during follow-up. Secondary endpoints were cardiovascular mortality and major bleeding events (BARC ≥3a). Clinical follow-up was performed at 1, 6, and 12 months and subsequently on an annual basis. Transesophageal echocardiography was performed at 1 and 12 months of follow-up. RESULTS: The study comprised 74 patients. The median age was 77 [72-83] years and 43% were women. The cohort exhibited a high prevalence of comorbidities and cardiovascular risk factors. The median CHA2DS2-VASc and HAS-BLED scores were 4 [3-6] and 4 [4-5], respectively. The median length of follow-up was 2.5 years (188 patients-year). During follow-up, device-related thrombosis occurred in 3 patients (4%). Ischemic stroke occurred in 1 patient (1.3%, rate 0.5%/y), representing a 90.9% relative risk reduction compared with the risk predicted by CHA2DS2-VASc. Major bleeding events occurred in 12 patients (16%, 6.4%/y), with a relative risk reduction of 26.4% of that predicted by HAS-BLED. Cardiovascular-related mortality was observed in 2 patients (2.7%). CONCLUSIONS: SAPT appears to be a safe and effective treatment following LAAC in patients at high ischemic and hemorrhagic risk. Further studies are needed to confirm our findings.


Asunto(s)
Fibrilación Atrial , Cierre del Apéndice Auricular Izquierdo , Inhibidores de Agregación Plaquetaria , Anciano , Femenino , Humanos , Masculino , Apéndice Atrial/diagnóstico por imagen , Apéndice Atrial/cirugía , Fibrilación Atrial/tratamiento farmacológico , Fibrilación Atrial/cirugía , Hemorragia/inducido químicamente , Hemorragia/epidemiología , Inhibidores de Agregación Plaquetaria/efectos adversos , Inhibidores de Agregación Plaquetaria/uso terapéutico , Estudios Prospectivos , Accidente Cerebrovascular/epidemiología , Trombosis/epidemiología , Resultado del Tratamiento , Anciano de 80 o más Años
4.
J Clin Med ; 11(24)2022 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-36556059

RESUMEN

The potential benefits of Lactobacillus gasseri LA806 in IBS were previously identified in a comprehensive preclinical research program. The purpose of this multicenter study was to explore in real-life conditions changes in IBS symptoms and quality of life in patients receiving a 4-week supplementation with L. gasseri LA806. Altogether 119 patients meeting Rome IV criteria for IBS were included, of whom 118 received the supplement. The majority of patients (71.8% (95% CI 63.6−79.9%)) manifested a ≥30% decrease in abdominal pain at 4 weeks, the mean abdominal pain score diminishing by 54.2% (from 5.3 ± 2.2 to 2.2 ± 2.4, p < 0.0001). A statistically significant decrease in abdominal pain was seen as early as the first week. A decrease of ≥30% in both abdominal pain score and global IBS symptom score was attained in 61.5% of patients (95% CI 51.7−71.2%). The mean IBS-SSS score fell by 152 ± 112 points (p = 0.001), with symptoms being attenuated in 85% of patients (CGI-I). Supplementation led to a 10-fold decrease in the number of patients reporting severe IBS symptoms. The concomitant intake of antidiarrheals, antispasmodics and analgesics decreased and quality of life scores significantly improved. These preliminary results warrant confirmation by a randomized, placebo-controlled study that this study will allow a better design.

5.
J Vis Exp ; (179)2022 01 29.
Artículo en Inglés | MEDLINE | ID: mdl-35156659

RESUMEN

Wood-boring invertebrates rapidly destroy marine timbers and wooden coastal infrastructure, causing billions of dollars of damage around the globe every year. As treatments of wood with broad spectrum biocides, such as creosote and chromated copper arsenate (CCA), are now restricted in marine use by legislation, naturally durable timber species and novel preservation methods of wood are required. These methods undergo testing in order to meet regulatory standards, such as the European standard for testing wood preservatives against marine borers, EN 275. Initial investigation of durable timbers species or wood preservative treatments can be achieved quickly and inexpensively through laboratory testing, which offers many advantages over marine field trials that are typically costly, long-term endeavours. Many species of Limnoria (gribble) are marine wood-boring crustaceans. Limnoria are ideal for use in laboratory testing of biodegradation of wood by marine wood-borers, due to the practicality of rearing them in aquaria and the ease of measuring their feeding rates on wood. Herein, we outline a standardizable laboratory test for assessing wood biodegradation using gribble.


Asunto(s)
Desinfectantes , Madera , Animales , Cobre/análisis , Desinfectantes/análisis , Invertebrados , Madera/química
6.
Clin Genitourin Cancer ; 19(6): 501-509, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34629300

RESUMEN

BACKGROUND: Docetaxel (DOCE) is a standard of care in metastatic castration-resistant prostate cancer (mCRPC). Several retrospective studies suggested a decrease in Prostate Cancer incidence and mortality with metformin (MET). MET has also demonstrated anti-tumor activity in Prostate Cancer preclinical models, with increased apoptosis when added to DOCE. We aimed at exploring the role of MET in combination with DOCE in mCRPC. PATIENTS AND METHODS: Non-diabetic mCRPC patients were randomly assigned to receive DOCE 75 mg/m2 every 21 days + prednisone (5 mg. BID) with either MET 850 mg BID (D+M) or placebo (D+P) up to 10 cycles. Prostate-Specific Antigen (PSA) response ≥50% from baseline was the primary end point. Secondary end points included objective response rate (ORR), progression-free survival (PFS), overall survival (OS), toxicity and quality of life (QoL). RESULTS: Out of 99 patients were randomized (D+M = 50; D+P = 49) in 10 French centers. The median follow-up was 86 (IQR 73-88) months. The PSA-response rate reached 66% in the D+M arm, but was not different from that observed in the D+P arm (63%, P = 0,94). In the D+M and D+P arms, the ORR was 28% and 24%, the median PFS was 7.8 and 6.0 months and the median OS was 27 and 20 months (ns), respectively. Diarrhea grade I to II was more frequent in the MET arm (66% vs. 43%). No impairment of QoL was observed. CONCLUSION: MET addition failed to improve the standard DOCE regimen in mCRPC. Further research targeting tumor cell metabolism should be performed.


Asunto(s)
Metformina , Neoplasias de la Próstata Resistentes a la Castración , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Supervivencia sin Enfermedad , Docetaxel/uso terapéutico , Humanos , Masculino , Metformina/uso terapéutico , Prednisona/uso terapéutico , Estudios Prospectivos , Antígeno Prostático Específico , Neoplasias de la Próstata Resistentes a la Castración/tratamiento farmacológico , Calidad de Vida , Estudios Retrospectivos , Resultado del Tratamiento
7.
J Clin Med ; 10(7)2021 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-33915971

RESUMEN

The LAmbreTM device is a novel system designed for left atrial appendage closure (LAAC). First registries showed a high rate of device implantation success. However, few mid-term results are available. We present our 1- and 12-month follow-up results for this device. This prospective, single-center registry included consecutive patients with nonvalvular atrial fibrillation who underwent LAAC with the LAmbreTM device. Transesophageal echocardiography (TEE) was performed at 1-month follow-up. In total, 55 patients were included. The population was elderly (75 ± 9.4 years), with a high proportion of comorbidities. The mean CHA2DS2-VASc and HAS-BLED scores were 4.6 ± 1.6 and 3.9 ± 1.0, respectively. Previous history of a major bleeding event was present in 37 patients (67.3%). Procedural success was achieved in 54 patients (98.2%). Device success was achieved in 100% of patients in whom device implantation was attempted (54 patients). Major in-hospital device-related complications included mortality of one patient (1.8%) and pericardial tamponade in two patients (3.6%); the incidence of stroke was 0%. No thrombus or significant leaks (≥5 mm) were observed on 1-month TEE. At 12 months, adverse events were overall death (1.8%), transient ischemic attack/ischemic stroke (1.8%), and major bleeding events (Bleeding Academic Research Consortium (BARC) 3a and 3c; 11%). In this high-risk population, the LAmbreTM device seems to be a safe and effective option for LAAC with a remarkable mid-term performance.

8.
J Clin Endocrinol Metab ; 106(1): e45-e60, 2021 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-33000146

RESUMEN

CONTEXT: In primary aldosteronism (PA), aldosterone secretion is relatively independent of the renin-angiotensin system, but can be regulated by several other stimuli. OBJECTIVE: To evaluate aldosterone response to several stimuli in a series of patients with PA secondary either to bilateral adrenal hyperplasia (BAH) or unilateral aldosterone-producing adenoma (APA). DESIGN AND SETTING: Prospective cohort study conducted in a university teaching hospital research center. PATIENTS: Forty-three patients with confirmed PA and subtyped by adrenal vein sampling (n = 39) were studied, including 11 with BAH, 28 with APA, and 4 with undefined etiology. We also studied 4 other patients with aldosterone and cortisol cosecretion. INTERVENTIONS: We systematically explored aberrant regulation of aldosterone using an in vivo protocol that included the following stimulation tests performed over 3 days under dexamethasone suppression: upright posture, mixed meal, adrenocorticotropin (ACTH) 1-24, gonadotropin-releasing hormone (GnRH), vasopressin, and serotonin R4 agonist. MAIN OUTCOME MEASURES: Positive response was defined as >50% renin or ACTH-independent increase in plasma aldosterone/cortisol concentration following the various stimulation tests. RESULTS: Renin-independent aldosterone secretion increased in response to several aberrant stimuli (upright posture, GnRH) in up to 83% of patients with APA or BAH in whom ACTH 1-24 and HT4R agonists also produced aldosterone oversecretion in all patients. The mean significant aberrant responses per patient was similar in BAH (4.6) and in APA (4.0). CONCLUSIONS: Aldosterone secretion in PA is relatively autonomous from the renin-angiotensin system, but is highly regulated by several other stimuli, which contributes to the large variability of aldosterone levels in PA patients.


Asunto(s)
Aldosterona/metabolismo , Hiperaldosteronismo/epidemiología , Hiperaldosteronismo/metabolismo , Neoplasias de la Corteza Suprarrenal/epidemiología , Neoplasias de la Corteza Suprarrenal/metabolismo , Glándulas Suprarrenales/metabolismo , Glándulas Suprarrenales/patología , Adenoma Corticosuprarrenal/epidemiología , Adenoma Corticosuprarrenal/metabolismo , Adulto , Anciano , Aldosterona/sangre , Técnicas de Diagnóstico Endocrino , Femenino , Hormona Liberadora de Gonadotropina , Humanos , Hidrocortisona/sangre , Hiperaldosteronismo/sangre , Hiperaldosteronismo/diagnóstico , Hiperplasia/metabolismo , Hiperplasia/patología , Masculino , Redes y Vías Metabólicas/fisiología , Persona de Mediana Edad , Estimulación Física/métodos , Prevalencia , Estudios Prospectivos , Quebec/epidemiología , Renina/sangre
10.
Molecules ; 24(7)2019 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-30934832

RESUMEN

The use of adequate thermal energy storage (TES) systems is an opportunity to increase energy efficiency in the building sector, and so decrease both commercial and residential energy consumptions. Nano-enhanced phase change materials (NEPCM) have attracted attention to address one of the crucial barriers (i.e. low thermal conductivity) to the adoption of phase change materials (PCM) in this sector. In the present study two PCM based on fatty acids, capric and palmitic acid, were nano-enhanced with low contents (1.0 wt.%, 1.5 wt.% and 3.0 wt.%) of copper (II) oxide (CuO) nanoparticles. Copper (II) oxide (CuO) was synthesized via coprecipitation method obtaining 60⁻120 nm diameter sized nanoparticles. Thermal stability and high thermal conductivity were observed for the nano-enhanced phase change materials (NEPCM) obtained. Experimental results revealed remarkable increments in NEPCM thermal conductivity, for instance palmitic acid thermal conductivity was increased up to 60% with the addition of 3 wt.% CuO nanoparticles. Moreover, CuO nanoparticles sedimentation velocity decreases when increasing its content.


Asunto(s)
Materiales de Construcción/análisis , Nanopartículas/análisis , Fenómenos Químicos , Nanopartículas/química , Nanopartículas/ultraestructura , Análisis Espectral , Conductividad Térmica , Termogravimetría
11.
Oncologist ; 22(11): 1339-1346, 2017 11.
Artículo en Inglés | MEDLINE | ID: mdl-28935772

RESUMEN

On November 19, 2015, a marketing authorization valid through the European Union was issued for carfilzomib in combination with lenalidomide and dexamethasone for the treatment of adult patients with multiple myeloma (MM) who have received at least one prior therapy.In a phase III trial in patients with relapsed MM, median progression-free survival (PFS) for patients treated with carfilzomib in combination with lenalidomide and dexamethasone (CRd) was 26.3 months versus 17.6 months for those receiving lenalidomide and dexamethasone alone (hazard ratio = 0.69; 95% confidence interval, 0.57-0.83; one-sided log-rank p value < .0001). The most frequently observed toxicity (grade ≥3, treatment arm vs. control arm) in the phase III trial included neutropenia (29.6% vs. 26.5%), anemia (17.9% vs. 17.7%), thrombocytopenia (16.8% vs. 12.3%), pneumonia (12.5% vs. 10.5%), fatigue (7.7% vs. 6.4%), hypertension (4.6% vs. 2.1%), diarrhea (3.8% vs. 4.1%), and respiratory tract infection (4.1% vs. 2.1%).The objective of this article is to summarize the scientific review of the application leading to regulatory approval in the European Union. The scientific review concluded that the gain in PFS of 8.7 months observed with the combination of CRd was considered clinically meaningful and was supported by a clear trend in overall survival benefit, although the data were not mature. The delay in disease progression appeared superior to available alternatives in the setting of relapsed MM at the time of the marketing authorization of carfilzomib. Therefore, given the overall accepted safety profile, which was considered manageable in the current context, the benefit risk for CRd was considered positive. IMPLICATIONS FOR PRACTICE: Carfilzomib (Kyprolis) was approved in the European Union in combination with lenalidomide and dexamethasone for the treatment of adult patients with multiple myeloma who have received at least one prior therapy. The addition of carfilzomib to lenalidomide and dexamethasone resulted in a clinically meaningful and statistically significant improvement of progression-free survival compared with lenalidomide and dexamethasone, which was supported by a clear trend in overall survival benefit, although the data were not mature. At the time of the marketing authorization of carfilzomib, the delay in disease progression appeared superior to available alternatives in the setting of relapsed multiple myeloma. In terms of safety, the overall accepted safety profile was considered manageable.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Mieloma Múltiple/tratamiento farmacológico , Recurrencia Local de Neoplasia/tratamiento farmacológico , Oligopéptidos/administración & dosificación , Adulto , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Dexametasona/administración & dosificación , Dexametasona/efectos adversos , Progresión de la Enfermedad , Supervivencia sin Enfermedad , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/clasificación , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/patología , Europa (Continente)/epidemiología , Femenino , Humanos , Lenalidomida , Masculino , Persona de Mediana Edad , Mieloma Múltiple/epidemiología , Mieloma Múltiple/patología , Recurrencia Local de Neoplasia/patología , Oligopéptidos/efectos adversos , Talidomida/administración & dosificación , Talidomida/efectos adversos , Talidomida/análogos & derivados
13.
Chemistry ; 13(6): 1842-50, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17115464

RESUMEN

The initial steps of an enantioselective Diels-Alder reaction catalyzed by a CuII-bissulfoximine complex were followed by EXAFS (EXAFS=extended X-ray absorption fine structure), EPR (EPR=electron paramagnetic resonance) spectroscopy (CW-EPR, FID-detected EPR, pulse ENDOR, HYSCORE; CW=continuous wave; ENDOR=electron nuclear double resonance; HYSCORE=hyperfine sublevel correlation; FID=free induction decay), and UV-visible spectroscopy. The complexes formed between the parent CuX2 (X=Cl-, Br-, TfO-, SbF6-) salts, the chiral bissulfoximine ligand (S,S)-1, and N-(1-oxoprop-2-en-1-yl)oxazolidin-2-one (2) as the substrate in CH2Cl2 were investigated in frozen and fluid solution. In all cases, penta- or hexacoordinated CuII centers were established. The complexes with counterions indicating high stereoselectivity (TfO- and SbF6-) reveal one unique species in which substrate 2 binds to pseudoequatorial positions (via O atoms), shifting the counterions to axial locations. On the other hand, those lacking stereoselectivity (X=Cl- and Br-) form two species in which the parent halogen anions remain at equatorial positions preventing the formation of geometries compatible with those found for X=TfO- and SbF6-.

14.
Bioorg Med Chem ; 14(23): 8109-25, 2006 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-16893650

RESUMEN

HIV-1 infection of the brain and PAF neurotoxicity are implicated in AIDS dementia complex. We previously reported that a trisubstituted piperazine derivative is able to diminish both HIV-1 replication in monocyte-derived macrophages and PAF-induced platelet aggregation. We report in this work new compounds obtained by modifying its piperazine substituents. The structure-activity relationship study shows that a better dual activity or even pure antiretroviral compounds can be obtained in this series.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida/complicaciones , Fármacos Anti-VIH/síntesis química , Antirretrovirales/síntesis química , Demencia/prevención & control , Piperazinas/farmacología , Factor de Activación Plaquetaria/antagonistas & inhibidores , Fármacos Anti-VIH/farmacología , Antirretrovirales/farmacología , Demencia/etiología , Relación Dosis-Respuesta a Droga , VIH-1 , Humanos , Piperazinas/síntesis química , Relación Estructura-Actividad
15.
Eur Biophys J ; 35(6): 495-501, 2006 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16572269

RESUMEN

We have performed a very extensive investigation of chromatin folding in different buffers over a wide range of ionic conditions similar to those found in eukaryotic cells. Our results show that in the presence of physiological concentrations of monovalent cations and/or low concentrations of divalent cations, small chicken erythrocyte chromatin fragments and chromatin from HeLa cells observed by transmission electron microscopy (TEM) show a compact folding, forming circular bodies of approximately 35 nm in diameter that were found previously in our laboratory in studies performed under very limited conditions. Since TEM images are obtained with dehydrated samples, we have performed atomic force microscopy (AFM) experiments to analyze chromatin structure in the presence of solutions containing different cation concentrations. The highly compact circular structures (in which individual nucleosomes are not visible as separated units) produced by small chromatin fragments in interphase ionic conditions observed by AFM are equivalent to the structures observed by TEM with chromatin samples prepared under the same ionic conditions. We have also carried out experiments of sedimentation and trypsin digestion of chromatin fragments; the results obtained confirm our AFM observations. Our results suggest that the compaction of bulk interphase chromatin in solution at room temperature is considerably higher than that generally considered in current literature. The dense chromatin folding observed in this study is consistent with the requirement of compact chromatin structures as starting elements for the building of metaphase chromosomes, but poses a difficult physical problem for gene expression during interphase.


Asunto(s)
Cationes/química , Ensamble y Desensamble de Cromatina/fisiología , Cromatina/química , Animales , Fenómenos Biofísicos , Biofisica , Pollos , Cromatina/ultraestructura , Eritrocitos , Células HeLa , Humanos , Microscopía de Fuerza Atómica , Microscopía Electrónica de Transmisión , Tripsina , Agua
16.
J Clin Endocrinol Metab ; 91(2): 361-4, 2006 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16278263

RESUMEN

CONTEXT: Calcitonin is a well-established tumor marker for medullary thyroid carcinoma (MTC). Because surgery is the only effective treatment for patients with MTC, the postoperative level of serum calcitonin will dictate whether residual disease was left behind and whether reintervention is necessary. RESULTS: We describe here the case of a 41-yr-old man with metastatic MTC. Despite extensive disease in the neck as well as metastatic lesions in the liver, his serum calcitonin, measured with a commercial one-step immunoradiometric assay, was only minimally elevated (244 ng/liter). After serial dilutions, a nonlinear relationship became evident, suggesting the presence of a "hook effect." Treatment of the serum with heterophilic blocking reagent revealed no change. Calcitonin was then measured with a different immunoradiometric assay and revealed a much higher level. Similar discrepancies were found in different samples from various patients when analyzed with different calcitonin immunoassays. CONCLUSION: To our knowledge, this is the first reported case of a phenomenon such as the hook effect in a calcitonin immunoradiometric assay in patients with MTC. Being aware of this phenomenon is important, because a low calcitonin result could give false reassurance to both the patient and the clinician and could dramatically change the prognosis of the patient.


Asunto(s)
Biomarcadores de Tumor/sangre , Calcitonina/sangre , Carcinoma Medular/sangre , Neoplasias de la Tiroides/sangre , Adulto , Carcinoma Medular/patología , Carcinoma Medular/secundario , Humanos , Ensayo Inmunorradiométrico/métodos , Neoplasias Hepáticas/sangre , Neoplasias Hepáticas/secundario , Neoplasias de la Tiroides/patología
17.
Int Immunol ; 17(8): 1047-57, 2005 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-15976033

RESUMEN

IFN-tau is a non-cytotoxic type I IFN responsible for maternal recognition of the foetus in ruminants. IFN-tau has been found to inhibit HIV replication more strongly than human IFN-alpha, particularly in human monocyte-derived macrophages, without associated toxicity. Ovine IFN-tau uses the same anti-viral cellular pathways as human IFN-alpha in human macrophages, principally inhibiting the early steps of the biological cycle of HIV, preventing the integration of HIV DNA into the host-cell genome. In this study, we investigated the immunomodulatory properties of IFN-tau in human macrophages. We found that IFN-tau increased the production of IL-10 and IL-6, but not of IL-1beta or tumour necrosis factor alpha, in unstimulated, LPS-stimulated and HIV-1/Ba-L-infected macrophages. We also found that treatment with IL-6 inhibited HIV replication. Moreover, the neutralization of IL-6 activity in the cell culture supernatants of IFN-tau-treated macrophages led to a decrease in the anti-retroviral effects of IFN-tau, suggesting that IL-6 was involved in the anti-viral activity induced by IFN-tau. By focusing on the very early steps of the biological cycle of HIV, we showed that IL-6 co-operated with IFN-tau to decrease intracellular HIV RNA levels 2 h after infection.


Asunto(s)
VIH-1/efectos de los fármacos , VIH-1/inmunología , Interferón Tipo I/farmacología , Interleucina-6/biosíntesis , Proteínas Gestacionales/farmacología , Animales , VIH-1/fisiología , Humanos , Factores Inmunológicos/farmacología , Técnicas In Vitro , Interleucina-1/biosíntesis , Interleucina-10/biosíntesis , Interleucina-10/farmacología , Interleucina-6/farmacología , Macrófagos/efectos de los fármacos , Macrófagos/inmunología , Macrófagos/virología , Proteínas Recombinantes/farmacología , Ovinos , Factor de Necrosis Tumoral alfa/biosíntesis , Replicación Viral/efectos de los fármacos
18.
J Med Chem ; 47(25): 6410-9, 2004 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-15566310

RESUMEN

The HIV-1 central nervous system infection leads to the onset of neurological impairments called AIDS dementia complex (ADC). PAF plays an important role in this pathology, as it is an HIV-1-induced neurotoxin produced by infected or activated macrophages and microglia, in the brain. We previously reported that PAF-antagonists bearing a trisubstituted piperazine presented in vitro anti-HIV-1 activity in human macrophages. To improve the pharmacological activities of our lead compound, 1a, we modified its carbamate function and evaluated both its antiretroviral and anti-PAF activities. One carbamate derivative (10c) demonstrated a similar antiviral activity but a higher anti-PAF potency, whereas 4a, with an ureide function, presents an increased antiviral activity and can be considered as a pure antiretroviral drug, as it does not present PAF-antagonism. Moreover, we measured the ability of 1a to cross the blood-brain barrier, using the in situ mouse brain perfusion method and its plasmatic concentrations after iv and po administration. The transport parameter measured (K(in)) proves that 1a is able to cross this biological barrier, but a pharmacokinetic study reveals its weak bioavailability in rats.


Asunto(s)
Fármacos Anti-VIH/síntesis química , VIH-1/efectos de los fármacos , Piperazinas/síntesis química , Factor de Activación Plaquetaria/antagonistas & inhibidores , Animales , Fármacos Anti-VIH/química , Fármacos Anti-VIH/farmacología , Disponibilidad Biológica , Barrera Hematoencefálica/metabolismo , Carbamatos/síntesis química , Carbamatos/química , Carbamatos/farmacología , Células Cultivadas , Humanos , Técnicas In Vitro , Macrófagos/efectos de los fármacos , Macrófagos/virología , Masculino , Ratones , Permeabilidad , Piperazinas/química , Piperazinas/farmacología , Agregación Plaquetaria/efectos de los fármacos , Conejos , Ratas , Ratas Sprague-Dawley , Relación Estructura-Actividad , Replicación Viral/efectos de los fármacos
19.
J Virol ; 77(23): 12914-20, 2003 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-14610214

RESUMEN

Tau interferon (IFN-tau) is a noncytotoxic type I IFN responsible for maternal recognition of the fetus in ruminants. IFN-tau inhibits human immunodeficiency virus (HIV) replication more strongly than human IFN-alpha, particularly in human monocyte-derived macrophages. In this study performed in human macrophages, IFN-tau efficiently inhibited the early steps of the biological cycle of HIV, decreasing intracellular HIV RNA and inhibiting the initiation of the reverse transcription of viral RNA into proviral DNA. Two mechanisms induced by IFN-tau treatment in macrophages may account for this inhibition: (i) the synthesis of the cellular antiviral factors such as 2',5'-oligoadenylate synthetase/RNase L and MxA protein and (ii) an increased production of MIP-1alpha, MIP-1beta, and RANTES, which are natural ligands of CCR5, the principal coreceptor of HIV on macrophages. Our results suggest that IFN-tau induces the same antiviral pathways in macrophages as other type I IFNs but without associated toxicity.


Asunto(s)
Quimiocinas CC/fisiología , VIH/efectos de los fármacos , Interferón Tipo I/farmacología , Proteínas Gestacionales/farmacología , Replicación Viral/efectos de los fármacos , VIH/genética , VIH/fisiología , Humanos , Macrófagos/metabolismo , Macrófagos/virología , ARN Viral/sangre , Transcripción Genética
20.
J Am Chem Soc ; 125(20): 6222-7, 2003 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-12785854

RESUMEN

The structure of Cu(II) complex 3 formed within the course of a stereoselective Diels-Alder reaction was investigated by EXAFS, CW-EPR at X- and W-band, HYSCORE, pulsed ENDOR, and UV-vis spectroscopy. The experimental techniques indicate that the chiral bis(sulfoximine) ligand (S,S)-1 and the dienophile form a tetragonally distorted complex in CH(2)Cl(2). The ligand binds to the Cu(II) center via the imine nitrogens, whereas the dienophile interacts via the carbonyl oxygen atoms. The additional sites of the first coordination sphere are occupied by counterions and, presumably, solvent molecules. At the axial position, a triflate anion binds via an oxygen atom.

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