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1.
Environ Int ; 179: 108131, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37586275

RESUMEN

COVID-19 pandemic had a significant impact on global public health. The spread of the disease was related to the high transmissibility of SARS-CoV-2 virus but incidence and mortality rate suggested a possible relationship with environmental factors. Air pollution has been hypothesized to play a role in the transmission of the virus and the resulting severity of the disease. Here we report a plausible in vitro toxicological mode of action by which fine particulate matter (PM2.5) could promote a higher infection rate of SARS-CoV-2 and severity of COVID-19 disease. PM2.5 promotes a 1.5 fold over-expression of the angiotensin 2 converting enzyme (ACE2) which is exploited by viral particles to enter human lung alveolar cells (1.5 fold increase in RAB5 protein) and increases their inflammatory state (IL-8 and NF-kB protein expression). Our results provide a basis for further exploring the possible synergy between biological threats and air pollutants and ask for a deeper understanding of how air quality could influence new pandemics in the future.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , COVID-19 , Humanos , Material Particulado/toxicidad , Material Particulado/análisis , SARS-CoV-2 , Pandemias , Contaminantes Atmosféricos/toxicidad , Contaminantes Atmosféricos/análisis , Contaminación del Aire/análisis
2.
ESMO Open ; 7(6): 100611, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36463731

RESUMEN

BACKGROUND: In ∼3%-5% of patients with metastatic disease, tumor origin remains unknown despite modern imaging techniques and extensive pathology work-up. With long diagnostic delays and limited and ineffective therapy options, the clinical outcome of patients with cancer of unknown primary (CUP) remains poor. Large-scale genome sequencing studies have revealed that tumor types can be predicted based on distinct patterns of somatic variants and other genomic characteristics. Moreover, actionable genomic events are present in almost half of CUP patients. This study investigated the clinical value of whole genome sequencing (WGS) in terms of primary tumor identification and detection of actionable events, in the routine diagnostic work-up of CUP patients. PATIENTS AND METHODS: A WGS-based tumor type 'cancer of unknown primary prediction algorithm' (CUPPA) was developed based on previously described principles and validated on a large pan-cancer WGS database of metastatic cancer patients (>4000 samples) and 254 independent patients, respectively. We assessed the clinical value of this prediction algorithm as part of routine WGS-based diagnostic work-up for 72 CUP patients. RESULTS: CUPPA correctly predicted the primary tumor type in 78% of samples in the independent validation cohort (194/254 patients). High-confidence predictions (>95% precision) were obtained for 162/254 patients (64%). When integrated in the diagnostic work-up of CUP patients, CUPPA could identify a primary tumor type for 49/72 patients (68%). Most common diagnoses included non-small-cell lung (n = 7), gastroesophageal (n = 4), pancreatic (n = 4), and colorectal cancer (n = 3). Actionable events with matched therapy options in clinical trials were identified in 47% of patients. CONCLUSIONS: Genome-based tumor type prediction can predict cancer diagnoses with high accuracy when integrated in the routine diagnostic work-up of patients with metastatic cancer. With identification of the primary tumor type in the majority of patients and detection of actionable events, WGS is a valuable diagnostic tool for patients with CUP.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Neoplasias Primarias Desconocidas , Humanos , Neoplasias Primarias Desconocidas/diagnóstico , Neoplasias Primarias Desconocidas/genética , Neoplasias Primarias Desconocidas/tratamiento farmacológico , Genómica , Secuenciación Completa del Genoma
3.
Acta Chir Orthop Traumatol Cech ; 89(2): 104-107, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35621399

RESUMEN

PURPOSE OF THE STUDY To evaluate a possible association between hip fracture and statin use. MATERIAL AND METHODS In this case-control study we compared the use of statins between two groups of 210 patients: the first group (case group) included patients hospitalized for hip fractures while the second group (control group) included patients who did not suffer femur bone injuries. The two groups were matched for age, sex, year of hospitalization and possible confounding factors. Inside the group of cases, we also evaluated the differences in terms of fracture type, presence of previous fragility fracture and mortality between statin users and non-users. RESULTS The use of statins was most common among patients without previous fractures (OR=0.54; 95% CI=0.33-0.89; p=0.0138), especially in older patients (OR=0.40; 95% CI=0.22-0.76). We did not find any significant difference in statin intake between men and women in the control group. In the case group, those who did not use statins were more likely to undergo a medial hip fracture (28.5% vs 16.1%). Patients from case group also presented a greater mortality (27.9% vs 19.35%) and an higher percentage of previous hip fractures (20.11% vs 9.7%). However, they didn't presented a significant higher rate of fragility fractures in other sites. DISCUSSION AND CONCLUSIONS Our study suggests a reduced hip fracture risk, especially in cases aged 80 or more, a different fracture pattern (lower percentage of medial fractures) and a reduced mortality at 9 months in patients treated with HMG-CoA reductase inhibitors, confirming the previous evidences reported in literature. Key words: statin, hip fractures, fracture risk, osteoporosis.


Asunto(s)
Fracturas de Cadera , Inhibidores de Hidroximetilglutaril-CoA Reductasas , Osteoporosis , Anciano , Huesos , Estudios de Casos y Controles , Femenino , Fracturas de Cadera/epidemiología , Fracturas de Cadera/prevención & control , Humanos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/efectos adversos , Masculino
4.
Injury ; 52(8): 2459-2462, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33731290

RESUMEN

INTRODUCTION: Periprosthetic femoral fractures (PFF) actually represent a serious public health problem. They are reported to occur in 0,1-4.5% of all patients undergoing total hip replacement (THR). PFF are commonly distinguished using the Vancouver classification. This study principal aim is to evaluate results obtained using the Intrauma Iron Lady® Conical Coupling locking plate for the treatment of Vancouver type B1 periprosthetic femoral fractures. MATERIALS AND METHODS: We enrolled 32 patients affected by Vancouver B1 PFF and treated with the same device. Metal cerclages were additionally used in 12 (38%) patients. A clinical and radiographical post-operative follow-up was then planned at 1, 3 and 6 months after surgery; than the follow-up was annually fixed. RESULTS: Mean age at the moment of trauma was 76,7 years. All involved femoral stem were uncemented and the they were all radiographically and intraoperativelly judged to be stable. Mean post-operative follow-up period was 5,8 years. 29 patients (91%) presented healed fracture at 6 months follow-up. 9% patients developed a superficial surgical site infection. DISCUSSION AND CONCLUSIONS: Literature highlights that Vancouver B1 PFF should be treated with open reduction and internal fixation (ORIF) using polyaxial locking plates. However, no single technique has gained universal acceptance to be superior that the other. The current reported healing rate ranges from 40 to 100%. Using the Intrauma Iron Lady® Conical Coupling locking plate, we obtained a healing rate of 91%; this data is consistent with recent literature. Moreover, the role of cerclages in addition to femoral plating is actually controversial because they potentially damage the soft callus vascularization. Our results showed no difference in term of healing rate between patients with and without cerclages, according with some of most recent articles. A prospective study with a higher number of patients should be carried out in order to better evaluate the role of cerclages on healing rate but also the complications frequency after PFF surgical treatment.


Asunto(s)
Artroplastia de Reemplazo de Cadera , Placas Óseas , Fracturas del Fémur , Fracturas Periprotésicas , Fracturas del Fémur/diagnóstico por imagen , Fracturas del Fémur/cirugía , Fijación Interna de Fracturas , Curación de Fractura , Humanos , Fracturas Periprotésicas/diagnóstico por imagen , Fracturas Periprotésicas/cirugía , Estudios Prospectivos , Reoperación , Estudios Retrospectivos
5.
Anal Chim Acta ; 1142: 201-210, 2021 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-33280698

RESUMEN

There is an increasing interest in determining the concentration of furanic compounds naturally formed in food aqueous matrices, by in situ, fast and low-cost methods. A sensor presenting such characteristics is here proposed, and characterized. It is based on a molecularly imprinted polymer (MIP) as a receptor with electrochemical transduction on a screen printed cell (SPC). The molecularly imprinted polymer has been developed for a particular furanic derivative, 2-furaldehyde (2-FAL). The detection bases on the reduction of 2-FAL selectively adsorbed on the polymer layer in contact with the working electrode. The polymer layer is simply formed by in situ polymerization, directly over the SPC and it was characterized by IR, SEM and electrochemical methods. Even if based on an easy and fast preparation procedure, the layer sufficiently adheres to the cell surface giving a reusable sensor. Square wave voltammetry (SWV) was applied as the signal acquisition method. The sensor performance in aqueous solution (NaCl 0.1 M) was tested, obtaining that the dose-response curve is fitted by the Langmuir adsorption isotherm. The sensitivity, and so the limit of detection, were noticeably improved by a chemometric approach based on the Design of experiment method. (optimized conditions: Estep = 0.03 V, Epulse = 0.066 V, f = 31 s-1). In water solution at pH around neutrality the dynamic range was from about 50 µM to 20 mM. Similar results were obtained for a white wine containing 12% ethanol, which has been considered as a typical example of beverage possibly containing furhaldehydes. The higher limit of quantification can be modulated by the amount of MIP deposited, while the lower detection limit by the conditions of the electrochemical measurement.


Asunto(s)
Impresión Molecular , Bebidas , Técnicas Electroquímicas , Electrodos , Furaldehído , Límite de Detección , Polímeros Impresos Molecularmente
8.
Clin Pharmacol Drug Dev ; 9(8): 929-937, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-31970932

RESUMEN

Microdose studies are exploratory trials to determine early drug pharmacokinetics in humans. In this trial we examined whether the pharmacokinetics of gemcitabine at a therapeutic dose could be predicted from the pharmacokinetics of a microdose. In this prospective, open-label microdosing study, a gemcitabine microdose (100 µg) was given intravenously to participants on day 1, followed by a therapeutic dose (1250 mg/m2 ) on day 2. Gemcitabine and its metabolite 2',2'-difluorodeoxyuracil (dFdU) were quantified in plasma and intracellularly by using liquid chromatography-mass spectrometry). Noncompartmental pharmacokinetic analysis was performed. Ten patients participated in this study. The mean area under the plasma concentration-time curve (AUC0-8 ) of gemcitabine after microdosing was 0.00074 h·mg/L and after therapeutic dosing was 16 h·mg/L. The mean AUC0-8 of dFdU following the microdose and therapeutic dose were 0.022 h·mg/L and 169 h·mg/L, respectively. Exposure to gemcitabine after the therapeutic dose was within 2-fold of the exposure following a microdose, when linearly extrapolated to 1250 mg/m2 . However, the shape of the concentration-time curve was different, as reflected by poor scalability in volume of distribution (939 L versus 222 L). Furthermore, intracellularly phosphorylated gemcitabine and phosphorylated dFdU levels could not be predicted from the microdose. The AUC0-8 of gemcitabine at therapeutic dose was accurately predicted by the pharmacokinetics of a microdose, when linearly extrapolated to 1250 mg/m2 . Volume of distribution, elimination rate constant, and intracellular pharmacokinetics of the therapeutic dose could not be predicted from the microdose, which demonstrates limitations of the microdose approach in this case.


Asunto(s)
Antimetabolitos Antineoplásicos/farmacocinética , Cromatografía Liquida/métodos , Desoxicitidina/análogos & derivados , Relación Dosis-Respuesta a Droga , Espectrometría de Masas/instrumentación , Administración Intravenosa , Anciano , Antimetabolitos Antineoplásicos/administración & dosificación , Antimetabolitos Antineoplásicos/sangre , Antimetabolitos Antineoplásicos/uso terapéutico , Área Bajo la Curva , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Desoxicitidina/administración & dosificación , Desoxicitidina/sangre , Desoxicitidina/farmacocinética , Desoxicitidina/uso terapéutico , Femenino , Humanos , Masculino , Mesotelioma/tratamiento farmacológico , Persona de Mediana Edad , Proyectos Piloto , Valor Predictivo de las Pruebas , Estudios Prospectivos , Timoma/tratamiento farmacológico , Gemcitabina
9.
J Biol Regul Homeost Agents ; 31(4 suppl 1): 121-127, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29186948

RESUMEN

Bone cement implantation syndrome (BCIS) is a rare form of intraoperative pulmonary embolism (EP) that occurs during cementation. It can be explained by two main theories: the monomer mediated model and the mechanic model. Our goal is to evaluate thromboelastographic changes in patients undergoing surgery for femoral neck fractures. We recruited 32 patients with a femoral neck fracture. The average age was 81.91 years (range 62-95). The patients were divided in two different groups: cemented hip arthroplasty (CC, 13 patients) and other surgical non-cemented techniques (SC, non-cemented hip arthroplasty, osteosynthesis). The coagulation was evaluated by TEG in the early pre-operatory (time A) and post-operatory (time B), both on native blood and on blood added with Heparinase. We used the t-test to compare the differences between the two groups. The coagulation index CI was modified on hypercoagulability by surgery in both groups, but without statistical significance between the two groups (p>0.05). R parameter decreases between time A and time B in the same way in both groups (p>0.05). Parameter MA had no major variations between time A and B, without statistical significance (p>0.05). From our study it is evident that although the surgery would result in a change in the layout of the TEG toward hypercoagulability, this is similar both in cemented and non-cemented surgical interventions for femoral neck fractures in elderly patients. An altered coagulation does not appear to be the cause or a factor in determining the BCIS.

10.
J Biol Regul Homeost Agents ; 31(4 suppl 1)2017.
Artículo en Inglés | MEDLINE | ID: mdl-29186945

RESUMEN

Gamma-glutamyltransferase (GGT) has been recently identified as a bone-resorbing factor. The aim of this study was to investigate the association between plasma GGT fractions levels and bone quality. Plasma GGT fractions were analysed by gel-filtration chromatography. Bone quality was established quantitatively by two micro-CT derived microarchitectural parameters: the BV/TV (mineralised bone volume/total volume), and the SMI (structure model index) that describes the rod-like (low resistant) or plate-like (high-resistant) shape of bone trabeculae. We enrolled 93 patients hospitalised for elective total hip replacement (group Arthrosis, n=46) or for proximal femoral fracture (group Fracture, n=47). Patients within the first quartile of BV/TV (Q1, osteoporotic patients, n=6) showed higher levels of b-GGT fraction [median (min-max): 3.37 (1.42­6.81)] compared to patients with normal bone density (fourth quartile Q4, n=10; 1.40 (0.83­4.36); p=0.0393]. Also, according to SMI, b-GGT value was higher in the subgroup with bone fragility [Q1, n=8: 1.36 (0.43­4.36); Q4, n=8: 5.10 (1.4 ­7.60); p=0.0117]. In conclusion, patients characterised by fragile bone structure showed specifically higher levels of plasma b-GGT activity thus suggesting fractional GGT analysis as a possible biomarker in the diagnosis of osteoporosis.

11.
Nutr Metab Cardiovasc Dis ; 26(1): 60-6, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26643211

RESUMEN

BACKGROUND AND AIMS: Childhood obesity promotes adverse changes in cardiovascular structure and function. This study evaluated whether these changes are related to intra-abdominal adiposity and associated cardiometabolic risk or to body-size induced hemodynamic overload. METHODS AND RESULTS: 55 obese children/adolescents and 35 healthy-weight controls underwent carotid, cardiac and abdominal ultrasound to assess carotid artery intima-media thickness (IMT), diameter, distension and stiffness, left ventricular (LV) dimension, mass and function and extent of intra-abdominal adiposity. As compared to controls with healthy BMI, obese children had higher systolic blood pressure (BP), stroke volume and lower total peripheral resistance (P < 0.001-0.0001), higher plasma triglycerides, glycated hemoglobin, insulin and HOMA-IR index (P = 0.01-<0.0001), higher carotid IMT, diameter and distension (P < 0.005-0.0005), higher LV diameter, wall thickness and mass (P < 0.001-0.0001), and impaired LV diastolic function assessed by myocardial longitudinal performance (P < 0.005). In entire population, independent determinants of carotid diameter, LV diameter, wall thickness and mass were fat-free mass (or stroke volume, respectively) and BP. Carotid distension was determined by carotid diameter and BP, and carotid IMT by carotid diameter, BP, HDL-cholesterol and glycated hemoglobin. LV diastolic performance was inversely related to preperitoneal fat thickness and plasma insulin levels. CONCLUSIONS: Obese youths present signs of impaired lipid and glucose metabolism, hyperdynamic circulation and cardiovascular changes. Increase in LV dimensions and mass and in carotid diameter and distension seems to reflect adaptation to body-size induced increase in hemodynamic load, changes in LV diastolic performance a negative impact of intra-abdominal adiposity and associated metabolic risk, and increase in IMT both adaptive remodeling and metabolic risk.


Asunto(s)
Adiposidad , Enfermedades Cardiovasculares/etiología , Hemodinámica , Grasa Intraabdominal/fisiopatología , Obesidad Infantil/complicaciones , Adolescente , Factores de Edad , Biomarcadores/sangre , Glucemia/análisis , Enfermedades Cardiovasculares/diagnóstico , Enfermedades Cardiovasculares/fisiopatología , Enfermedades de las Arterias Carótidas/diagnóstico , Enfermedades de las Arterias Carótidas/etiología , Enfermedades de las Arterias Carótidas/fisiopatología , Grosor Intima-Media Carotídeo , Estudios de Casos y Controles , Niño , Femenino , Humanos , Hipertrofia Ventricular Izquierda/diagnóstico , Hipertrofia Ventricular Izquierda/etiología , Hipertrofia Ventricular Izquierda/fisiopatología , Lípidos/sangre , Masculino , Obesidad Infantil/sangre , Obesidad Infantil/diagnóstico , Obesidad Infantil/fisiopatología , Medición de Riesgo , Factores de Riesgo , Disfunción Ventricular Izquierda/diagnóstico , Disfunción Ventricular Izquierda/etiología , Disfunción Ventricular Izquierda/fisiopatología , Función Ventricular Izquierda , Remodelación Ventricular
12.
Cell Death Differ ; 22(12): 2020-33, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26045047

RESUMEN

NF-κB-inducing kinase (NIK) is well-known for its role in promoting p100/NF-κB2 processing into p52, a process defined as the alternative, or non-canonical, NF-κB pathway. Here we reveal an unexpected new role of NIK in TNFR1-mediated RIP1-dependent apoptosis, a consequence of TNFR1 activation observed in c-IAP1/2-depleted conditions. We show that NIK stabilization, obtained by activation of the non-death TNFRs Fn14 or LTßR, is required for TNFα-mediated apoptosis. These apoptotic stimuli trigger the depletion of c-IAP1/2, the phosphorylation of RIP1 and the RIP1 kinase-dependent assembly of the RIP1/FADD/caspase-8 complex. In the absence of NIK, the phosphorylation of RIP1 and the formation of RIP1/FADD/caspase-8 complex are compromised while c-IAP1/2 depletion is unaffected. In vitro kinase assays revealed that recombinant RIP1 is a bona fide substrate of NIK. In vivo, we demonstrated the requirement of NIK pro-death function, but not the processing of its substrate p100 into p52, in a mouse model of TNFR1/LTßR-induced thymus involution. In addition, we also highlight a role for NIK in hepatocyte apoptosis in a mouse model of virus-induced TNFR1/RIP1-dependent liver damage. We conclude that NIK not only contributes to lymphoid organogenesis, inflammation and cell survival but also to TNFR1/RIP1-dependent cell death independently of the alternative NF-κB pathway.


Asunto(s)
Proteínas Activadoras de GTPasa/metabolismo , FN-kappa B/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Receptores Tipo I de Factores de Necrosis Tumoral/metabolismo , Animales , Apoptosis/efectos de los fármacos , Caspasa 8/química , Caspasa 8/metabolismo , Línea Celular , Proteína de Dominio de Muerte Asociada a Fas/química , Proteína de Dominio de Muerte Asociada a Fas/metabolismo , Proteínas Activadoras de GTPasa/química , Células HEK293 , Humanos , Proteínas Inhibidoras de la Apoptosis/genética , Proteínas Inhibidoras de la Apoptosis/metabolismo , Hígado/efectos de los fármacos , Hígado/metabolismo , Hígado/patología , Receptor beta de Linfotoxina/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Fosforilación , Proteínas Serina-Treonina Quinasas/deficiencia , Proteínas Serina-Treonina Quinasas/genética , Transducción de Señal/efectos de los fármacos , Timo/metabolismo , Timo/patología , Factor de Necrosis Tumoral alfa/farmacología , Quinasa de Factor Nuclear kappa B
13.
Musculoskelet Surg ; 99(2): 105-11, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25845671

RESUMEN

PURPOSES: It is widely known that in Orthopaedics, as in each specialty, the academic influence of an article is also determined by the number of times the article is cited. The aim of this study was to identify the 50 most frequently cited Italian orthopaedics journal articles and to analyse the characteristics that might have made them more citable. METHODS: Science Citation Index Expanded was searched for the 50 most frequently cited Italian orthopaedics journal articles between 1988 and 2013 in the subject category "Orthopaedics". RESULTS: The 50 most frequently cited articles were all published in English and were published in 12 of the 67 journals in the subject category "Orthopaedics" in the Institute for Scientific Information Web Science (Thomson Reuters, New York, New York, USA). One half of the articles were published before 2000 and the other half later. The number of citations ranged from 423 of the first article (mean citation/years 21.15) to 83 of the fiftieth (mean citation/years 16.60). The articles were all categorized under orthopaedic field, but each of them spanned from orthopaedics to a specific sub-specialty. The majority was clinical articles (n = 39), and the most common fields were sport orthopaedic surgery (including arthroscopy and cartilage) (n = 19) and biomechanics (n = 12). CONCLUSIONS: This list of 50 most frequently cited Italian articles is, to our knowledge, significantly important for the general orthopaedic scientific community, particularly for the Italian orthopaedic community. Researchers and doctors may use this work to make their future publications more influential and citable.


Asunto(s)
Bibliometría , Ortopedia/estadística & datos numéricos , Humanos , Italia , Lenguaje
14.
Rev Sci Instrum ; 86(2): 023903, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25725859

RESUMEN

Mössbauer spectroscopy is an essential tool to investigate the structure of Fe supported catalysts and their changes, when they are used in the Fischer-Tropsch synthesis. A cell, that allows keeping the samples in the same atmosphere of the reduction treatment, was designed in order to characterize the Fe species without changing the working atmosphere avoiding the oxidation. It allows to measure at low temperatures in a helium closed-cycle refrigerator. Besides, this cell is useful to perform Mössbauer measurements on the used catalysts, preserving the oxidation of its species, using an inert atmosphere. In this work, we describe the details of this new cell and, as an example of its utility, we present the results obtained with a system of 12 nm iron oxide nanoparticles supported on a mesoporous silica matrix.

15.
Leukemia ; 29(5): 1163-76, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25394713

RESUMEN

Deregulated expression of glycolytic enzymes contributes not only to the increased energy demands of transformed cells but also has non-glycolytic roles in tumors. However, the contribution of these non-glycolytic functions in tumor progression remains poorly defined. Here, we show that elevated expression of glyceraldehyde-3-phosphate dehydrogenase (GAPDH), but not of other glycolytic enzymes tested, increased aggressiveness and vascularization of non-Hodgkin's lymphoma. Elevated GAPDH expression was found to promote nuclear factor-κB (NF-κB) activation via binding to tumor necrosis factor receptor-associated factor-2 (TRAF2), enhancing the transcription and the activity of hypoxia-inducing factor-1α (HIF-1α). Consistent with this, inactive mutants of GAPDH failed to bind TRAF2, enhance HIF-1 activity or promote lymphomagenesis. Furthermore, elevated expression of gapdh mRNA in biopsies from diffuse large B-cell non-Hodgkin's lymphoma patients correlated with high levels of hif-1α, vegf-a, nfkbia mRNA and CD31 staining. Collectively, these data indicate that deregulated GAPDH expression promotes NF-κB-dependent induction of HIF-1α and has a key role in lymphoma vascularization and aggressiveness.


Asunto(s)
Regulación Enzimológica de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Gliceraldehído 3-Fosfato Deshidrogenasa (NADP+)/metabolismo , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Linfoma no Hodgkin/metabolismo , Subunidad p50 de NF-kappa B/metabolismo , Animales , Biopsia , Línea Celular Tumoral , Inhibidores Enzimáticos/química , Células HeLa , Humanos , Linfoma/metabolismo , Ratones , Ratones Transgénicos , Fenotipo , Proteínas Proto-Oncogénicas c-myc/metabolismo , Factor 2 Asociado a Receptor de TNF/metabolismo , Factor A de Crecimiento Endotelial Vascular/metabolismo
17.
Cell Death Dis ; 5: e1406, 2014 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-25188516

RESUMEN

Rapidly proliferating cells, such as cancer cells, have adopted aerobic glycolysis rather than oxidative phosphorylation to supply their energy demand; this phenomenon is known as 'the Warburg effect'. It is now widely accepted that during apoptosis the loss of energy production, orchestrated by caspases, contributes to the dismantling of the dying cell. However, how this loss of energy production occurs is still only partially known. In the present work, we established that during apoptosis the level of cellular ATP decreased in a caspase-dependent manner. We demonstrated that this decrease in ATP content was independent of any caspase modification of glucose uptake, ATP consumption or reactive oxygen species production but was dependent on a caspase-dependent inhibition of glycolysis. We found that the activity of the two glycolysis-limiting enzymes, phosphofructokinase and pyruvate kinase, were affected by caspases, whereas the activity of phosphoglycerate kinase was not, suggesting specificity of the effect. Finally, using a metabolomic analysis, we observed that caspases led to a decrease in several key metabolites, including phosphoserine, which is a major regulator of pyruvate kinase muscle isozyme activity. Thus, we have established that during apoptosis, caspases can shut down the main energy production pathway in cancer cells, leading to the impairment in the activity of the two enzymes controlling limiting steps of glycolysis.


Asunto(s)
Caspasas/metabolismo , Glucosa/metabolismo , Adenosina Trifosfato/metabolismo , Clorometilcetonas de Aminoácidos/farmacología , Apoptosis/efectos de los fármacos , Inhibidores de Caspasas/farmacología , Caspasas/química , Desoxiglucosa/farmacología , Glucólisis/efectos de los fármacos , Células HeLa , Humanos , Fosfofructoquinasa-1/metabolismo , Piruvato Quinasa/metabolismo , Quinolinas/farmacología , Especies Reactivas de Oxígeno/metabolismo , Rutamicina/farmacología , Estaurosporina/farmacología
18.
Cell Death Differ ; 20(8): 1043-54, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23645209

RESUMEN

Increased glucose catabolism and resistance to cell death are hallmarks of cancers, but the link between them remains elusive. Remarkably, under conditions where caspases are inhibited, the process of cell death is delayed but rarely blocked, leading to the occurrence of caspase-independent cell death (CICD). Escape from CICD is particularly relevant in the context of cancer as apoptosis inhibition only is often not sufficient to allow oncogenic transformation. While most glycolytic enzymes are overexpressed in tumors, glyceraldehyde-3-phosphate dehydrogenase (GAPDH) is of particular interest as it can allow cells to recover from CICD. Here, we show that GAPDH, but no other glycolytic enzymes tested, when overexpressed could bind to active Akt and limit its dephosphorylation. Active Akt prevents FoxO nuclear localization, which precludes Bcl-6 expression and leads to Bcl-xL overexpression. The GAPDH-dependent Bcl-xL overexpression is able to protect a subset of mitochondria from permeabilization that are required for cellular survival from CICD. Thus, our work suggests that GAPDH overexpression could induce Bcl-xL overexpression and protect cells from CICD-induced chemotherapy through preservation of intact mitochondria that may facilitate tumor survival and chemotherapeutic resistance.


Asunto(s)
Apoptosis/fisiología , Caspasas/fisiología , Gliceraldehído 3-Fosfato Deshidrogenasa (NADP+)/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Regulación hacia Arriba/fisiología , Proteína bcl-X/metabolismo , Muerte Celular/fisiología , Línea Celular Tumoral , Supervivencia Celular/fisiología , Células HEK293 , Células HeLa , Humanos , Mitocondrias/fisiología , Fosfoglicerato Quinasa/fisiología , Fosfopiruvato Hidratasa/fisiología , Unión Proteica/fisiología
19.
Nanotechnology ; 24(17): 175601, 2013 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-23548801

RESUMEN

A new approach to thermal decomposition of organic iron precursors is reported, which results in a simpler and more economical method to produce well crystallized γ-Fe2O3 nanoparticles (NPs) with average sizes within the 3-17 nm range. The NPs were characterized by TEM, SAED, XRD, DLS-QELS, Mössbauer spectroscopy at different temperatures, FT-IR and magnetic measurements. The obtained γ-Fe2O3 NPs are coated with oleic acid and, in a lower quantity, with oleylamine (about 1.5 nm in thickness). It was shown that changing operative variables allows us to tune the average particle diameters and obtain a very narrow or monodisperse distribution of sizes. The γ-Fe2O3 NPs behave superparamagnetically at room temperature and their magnetization saturation is reduced by about 34% in comparison with bulk maghemite. The results indicate that the distance between two neighbour NPs, generated by the coating, of about 3 nm is insufficient to inhibit interparticle magnetic interactions when the average diameter is 8.8 nm. The good quality of the NPs, obtained through the present low-cost and easy-handling process, open a new perspective for future technological applications.


Asunto(s)
Nanopartículas de Magnetita/química , Nanotecnología/métodos , Nanopartículas de Magnetita/ultraestructura , Nanotecnología/economía , Tamaño de la Partícula , Espectroscopía Infrarroja por Transformada de Fourier , Espectroscopía de Mossbauer , Temperatura
20.
J Phys Chem B ; 117(13): 3613-23, 2013 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-23343421

RESUMEN

An aqueous self-assembled micellar system (sodium dodecyl sulfate, SDS, decorated with various adhesive sites, cryptand Kryptofix 222 and crown ether 18-Crown-6 molecules) has been investigated by dynamic light scattering (DLS) and small angle x-ray scattering (SAXS) to have insights into the micellar structure, the micellar interactions, and the aggregation properties of the system. DLS demonstrates the existence of populations of aggregates in the submicrometer/micrometer range, while the Guinier analysis of the SAXS curves helps in detailing objects smaller than 30 nm. The aggregates of micelles are here named cluster phases of micelles (CPMs). Considering that SDS micelles in water do not aggregate at low concentration, it is shown that macrocyclic ligands induce the SDS micelle aggregation as a function of the concentration (i.e., investigated ligand/SDS molar ratios are 5.0, 1.5, 1.0, and 0.5) and hydrophobicity of the adhesive sites. The sizes and the percentages of the micelles and the CPMs have been monitored to test the stability and reversibility of the system. DLS results clearly show that the aggregation processes of the decorated micelles are reproducible at time intervals of the order of 1 month, while the stability may not be entirely maintained after a year. As an issue of particular relevance, the higher the ligand/surfactant molar ratio, the larger are the CPMs induced. The K222 ligand results in being more effective in promoting the micellar aggregation than 18C6 as a consequence of the different hydrophobicity.


Asunto(s)
Compuestos Bicíclicos Heterocíclicos con Puentes/química , Éteres Corona/química , Compuestos Macrocíclicos/química , Dodecil Sulfato de Sodio/química , Ligandos , Micelas , Soluciones
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