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1.
BMC Public Health ; 16: 407, 2016 05 16.
Artículo en Inglés | MEDLINE | ID: mdl-27183821

RESUMEN

BACKGROUND: Excessive summer heat is a serious environmental health problem in Skopje, the capital and largest city of the former Yugoslav Republic of Macedonia. This paper attempts to forecast the impact of heat on mortality in Skopje in two future periods under climate change and compare it with a historical baseline period. METHODS: After ascertaining the relationship between daily mean ambient air temperature and daily mortality in Skopje, we modelled the evolution of ambient temperatures in the city under a Representative Concentration Pathway scenario (RCP8.5) and the evolution of the city population in two future time periods: 2026-2045 and 2081-2100, and in a past time period (1986-2005) to serve as baseline for comparison. We then calculated the projected average annual mortality attributable to heat in the absence of adaptation or acclimatization during those time windows, and evaluated the contribution of each source of uncertainty on the final impact. RESULTS: Our estimates suggest that, compared to the baseline period (1986-2005), heat-related mortality in Skopje would more than double in 2026-2045, and more than quadruple in 2081-2100. When considering the impact in 2081-2100, sampling variability around the heat-mortality relationship and climate model explained 40.3 and 46.6 % of total variability. CONCLUSION: These results highlight the importance of a long-term perspective in the public health prevention of heat exposure, particularly in the context of a changing climate.


Asunto(s)
Cambio Climático/estadística & datos numéricos , Calor/efectos adversos , Modelos Teóricos , Mortalidad/tendencias , Salud Ambiental , Europa (Continente) , Humanos , Salud Pública , República de Macedonia del Norte/epidemiología , Estaciones del Año , Incertidumbre
2.
Neuroimage ; 59(1): 193-201, 2012 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-21807103

RESUMEN

Glioblastoma (GBM) is the most common and lethal primary malignant brain tumor in humans. Because the phosphatidylinositol-3-kinase (PI3K) signaling pathway is activated in more than 88% of GBM, new drugs which target this pathway, such as the mTOR inhibitor Everolimus, are currently in clinical trials. Early tumor response to molecularly targeted treatments remains challenging to assess non-invasively, because it is often associated with tumor stasis or slower tumor growth. Innovative neuroimaging methods are therefore critically needed to provide metabolic or functional information that is indicative of targeted therapeutic action at early time points during the course of treatment. In this study, we demonstrated for the first time that hyperpolarized (HP) 13C magnetic resonance spectroscopic imaging (MRSI) can be used on a clinical MR system to monitor early metabolic response of orthotopic GBM tumors to Everolimus treatment through measurement of the HP lactate-to-pyruvate ratios. The study was performed on a highly invasive non-enhancing orthotopic GBM tumor model in rats (GS-2 tumors), which replicates many fundamental features of human GBM tumors. Seven days after initiation of treatment there was a significant drop in the HP lactate-to-pyruvate ratio from the tumor tissue in treated animals relative to day 0 (67%±27% decrease). In the control group, no significant changes in the HP lactate-to-pyruvate ratios were observed. Importantly, at the 7 day time point, conventional MR imaging (MRI) was unable to detect a significant difference in tumor size between control and treated groups. Inhibition of tumor growth by conventional MRI was observed from day 15 of treatment. This implies that the decrease in the HP lactate-to-pyruvate ratio could be detected before any treatment-induced inhibition of tumor growth. Using immunohistochemical staining to further examine tumor response to treatment, we found that the decrease in the HP lactate-to-pyruvate ratio was associated with a drop in expression of lactate dehydrogenase, the enzyme that catalyzes pyruvate to lactate conversion. Also evident was decreased staining for carbonic anhydrase IX (CA-IX), an indicator of hypoxia-inducible factor 1α (HIF-1α) activity, which, in turn, regulates expression of lactate dehydrogenase. To our knowledge, this study is the first report of the use of HP 13C MRSI at a clinical field strength to monitor GBM response to molecularly targeted treatments. It highlights the potential of HP lactate-to-pyruvate ratio as an early biomarker of response, thereby supporting further investigation of this non-invasive imaging approach for eventual clinical application.


Asunto(s)
Antineoplásicos/uso terapéutico , Neoplasias Encefálicas/tratamiento farmacológico , Glioblastoma/tratamiento farmacológico , Espectroscopía de Resonancia Magnética/métodos , Neuroimagen/métodos , Sirolimus/análogos & derivados , Animales , Radioisótopos de Carbono/uso terapéutico , Modelos Animales de Enfermedad , Everolimus , Humanos , Masculino , Ratas , Ratas Desnudas , Sirolimus/uso terapéutico , Ensayos Antitumor por Modelo de Xenoinjerto
3.
Analyst ; 136(12): 2578-85, 2011 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-21394377

RESUMEN

Measurement of glutathione (GSH) and glutathione disulfide (GSSG) is a crucial tool to assess cellular redox state. Herein we report a direct approach to determine intracellular GSH based on a rapid chromatographic separation coupled with acidic potassium permanganate chemiluminescence detection, which was extended to GSSG by incorporating thiol blocking and disulfide bond reduction. Importantly, this simple procedure avoids derivatisation of GSH (thus minimising auto-oxidation) and overcomes problems encountered when deriving the concentration of GSSG from 'total GSH'. The linear range and limit of detection for both analytes were 7.5 × 10(-7) to 1 × 10(-5) M, and 5 × 10(-7) M, respectively. GSH and GSSG were determined in cultured muscle cells treated for 24 h with glucose oxidase (0, 15, 30, 100, 250 and 500 mU mL(-1)), which exposed them to a continuous source of reactive oxygen species (ROS). Both analyte concentrations were greater in myotubes treated with 100 or 250 mU mL(-1) glucose oxidase (compared to untreated controls), but were significantly lower in myotubes treated with 500 mU mL(-1) (p < 0.05), which was rationalised by considering measurements of H(2)O(2) and cell viability. However, the GSH/GSSG ratio in myotubes treated with 100, 250 and 500 mU mL(-1) glucose oxidase exhibited a dose-dependent decrease that reflected the increase in intracellular ROS.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Disulfuro de Glutatión/análisis , Glutatión/análisis , Mediciones Luminiscentes/métodos , Permanganato de Potasio/química , Animales , Línea Celular , Análisis de Inyección de Flujo , Glucosa Oxidasa/metabolismo , Peróxido de Hidrógeno/análisis , Ratones , Mioblastos/metabolismo , Estrés Oxidativo , Especies Reactivas de Oxígeno/química , Especies Reactivas de Oxígeno/metabolismo
4.
Cell Metab ; 24(5): 649-650, 2016 11 08.
Artículo en Inglés | MEDLINE | ID: mdl-27829133

RESUMEN

Both cancer cells and activated T and NK immune cells display enhanced nutrient uptake and metabolism characteristic of the Warburg phenotype. In this issue of Cell Metabolism, Brand et al. (2016) demonstrate that cancer cell LDHA-derived lactic acid selectively disables T and NK cell activation and tumor immune surveillance.


Asunto(s)
Células Asesinas Naturales/inmunología , Ácido Láctico , Humanos , Activación de Linfocitos/inmunología , Neoplasias/inmunología
5.
Oncotarget ; 7(50): 83462-83475, 2016 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-27825143

RESUMEN

Tristetraprolin (TTP) is an RNA-binding protein that post-transcriptionally suppresses gene expression by delivering mRNA cargo to processing bodies (P-bodies) where the mRNA is degraded. TTP functions as a tumor suppressor in a mouse model of B cell lymphoma, and in some human malignancies low TTP expression correlates with reduced survival. Here we report important prognostic and functional roles for TTP in human prostate cancer. First, gene expression analysis of prostate tumors revealed low TTP expression correlates with patients having high-risk Gleason scores and increased biochemical recurrence. Second, in prostate cancer cells with low levels of endogenous TTP, inducible TTP expression inhibits their growth and proliferation, as well as their clonogenic growth. Third, TTP functions as a tumor suppressor in prostate cancer, as forced TTP expression markedly impairs the tumorigenic potential of prostate cancer cells in a mouse xenograft model. Finally, pathway analysis of gene expression data suggested metabolism is altered by TTP expression in prostate tumor cells, and metabolic analyses revealed that such processes are impaired by TTP, including mitochondrial respiration. Collectively, these findings suggest that TTP is an important prognostic indicator for prostate cancer, and augmenting TTP function would effectively disable the metabolism and proliferation of aggressive prostate tumors.


Asunto(s)
Proliferación Celular , Metabolismo Energético , Neoplasias de la Próstata/metabolismo , Tristetraprolina/metabolismo , Proteínas Supresoras de Tumor/metabolismo , Animales , Antibióticos Antineoplásicos/farmacología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia sin Enfermedad , Relación Dosis-Respuesta a Droga , Doxorrubicina/farmacología , Metabolismo Energético/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica , Redes Reguladoras de Genes , Humanos , Calicreínas/sangre , Masculino , Ratones Desnudos , Clasificación del Tumor , Antígeno Prostático Específico/sangre , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/patología , Transducción de Señal , Factores de Tiempo , Tristetraprolina/genética , Proteínas Supresoras de Tumor/genética , Ensayos Antitumor por Modelo de Xenoinjerto
6.
Neoplasia ; 5(6): 489-94, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-14965442

RESUMEN

ING-1(heMAb), a human-engineered monoclonal antibody (MAb) that specifically targets the epithelial cell adhesion molecule (Ep-CAM), kills adenocarcinoma cells in vitro and inhibits tumor growth in vivo. In the current study, we evaluated the efficacy of ING-1(heMAb) in a murine model of cancer metastases. Mice received intravenous dosing of 1 mg/kg ING-1(heMAb), twice a week, starting on day 2 or day 5. A negative control group received 1 mg/kg human immunoglobulin G with the same dose frequency starting on day 2. A positive control group received weekly 100 mg/kg 5-flurouracil/leucovorin starting on day 2. ING-1(heMAb)/day 2 treatment significantly reduced both the number of visible tumor nodules in body cavities (P <.01) and the number of metastases on lung surfaces (P <.005). The treatment also resulted in a 91% reduction of micrometastases in lung tissues (P <.0001). Delaying ING-1(heMAb) treatment until day 5 caused 54% reduction in micrometastases (P <.005). Our results indicate that a number of parameters, including treatment starting day, dose level, and dose frequency, are critical in achieving the optimal efficacy of ING-1(heMAb). We conclude that ING-1(heMAb) effectively reduced tumor metastases in a murine cancer model. Immunotherapy with ING-1(heMAb) may be beneficial in treating human metastatic diseases.


Asunto(s)
Adenocarcinoma/tratamiento farmacológico , Anticuerpos Monoclonales/uso terapéutico , Antígenos de Neoplasias , Neoplasias Pulmonares/tratamiento farmacológico , Metástasis de la Neoplasia/tratamiento farmacológico , Adenocarcinoma/secundario , Animales , Antineoplásicos/uso terapéutico , Moléculas de Adhesión Celular/inmunología , Molécula de Adhesión Celular Epitelial , Fluorouracilo/uso terapéutico , Células HT29 , Humanos , Leucovorina/uso terapéutico , Neoplasias Pulmonares/secundario , Ratones , Trasplante de Neoplasias , Factores de Tiempo
7.
Neoplasia ; 5(2): 146-54, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-12659687

RESUMEN

ING-1(heMAb), a Human Engineered monoclonal antibody to epithelial cell adhesion molecule (Ep-CAM), was evaluated for its in vitro and in vivo activity. The dissociation constant of ING-1(heMAb) for binding to Ep-CAM on HT-29 human colon tumor cells was 2 to 5 nM, similar to chimeric ING-1. In antibody-dependent cellular cytotoxicity and complement-dependent cytotoxicity assays, ING-1(heMAb) caused a concentration-dependent lysis of BT-20 breast, MCF-7 breast, HT-29 colon, and CACO-2 colon tumor cells, with maximum cytolysis at approximately 1 microg/ml. After an intravenous injection in rats, plasma ING-1(heMAb) levels declined with an alpha half-life of 8 to 11 hours, and a beta half-life of 20 days, typical of an IgG in a species without the target for ING-1. In nude mice with human HT-29 colon tumors, plasma ING-1(heMAb) levels declined more rapidly than in non-tumor-bearing mice, suggesting an enhanced clearance via the tumor-associated human Ep-CAM. In nude mice, intravenous treatments with ING-1(heMAb) twice a week for 3 weeks significantly suppressed the growth of human HT-29 colon and PC-3 prostate tumors in a dose-dependent manner, with 1.0 mg/kg providing the greatest benefit. These results indicate that Human Engineered ING-1(heMAb) is a high-affinity antibody with potent in vitro activity that targets and suppresses the growth of human tumors in vivo.


Asunto(s)
Anticuerpos Monoclonales/química , Antígenos de Neoplasias/química , Moléculas de Adhesión Celular/química , Animales , Antígenos de Neoplasias/inmunología , Adhesión Celular , Moléculas de Adhesión Celular/inmunología , Línea Celular Tumoral , Relación Dosis-Respuesta a Droga , Ensayo de Inmunoadsorción Enzimática , Molécula de Adhesión Celular Epitelial , Humanos , Inmunoglobulina G/química , Cinética , Masculino , Ratones , Ratones Desnudos , Trasplante de Neoplasias , Unión Proteica , Ratas , Factores de Tiempo
8.
Cancer Res ; 74(3): 908-20, 2014 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-24285728

RESUMEN

Myc oncoproteins induce genes driving aerobic glycolysis, including lactate dehydrogenase-A that generates lactate. Here, we report that Myc controls transcription of the lactate transporter SLC16A1/MCT1 and that elevated MCT1 levels are manifest in premalignant and neoplastic Eµ-Myc transgenic B cells and in human malignancies with MYC or MYCN involvement. Notably, disrupting MCT1 function leads to an accumulation of intracellular lactate that rapidly disables tumor cell growth and glycolysis, provoking marked alterations in glycolytic intermediates, reductions in glucose transport, and in levels of ATP, NADPH, and ultimately, glutathione (GSH). Reductions in GSH then lead to increases in hydrogen peroxide, mitochondrial damage, and ultimately, cell death. Finally, forcing glycolysis by metformin treatment augments this response and the efficacy of MCT1 inhibitors, suggesting an attractive combination therapy for MYC/MCT1-expressing malignancies.


Asunto(s)
Glutatión/biosíntesis , Ácido Láctico/metabolismo , Transportadores de Ácidos Monocarboxílicos/genética , Proteínas Proto-Oncogénicas c-myc/metabolismo , Simportadores/genética , Animales , Muerte Celular/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular , Transformación Celular Neoplásica/genética , Análisis por Conglomerados , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Glucólisis/efectos de los fármacos , Glucólisis/genética , Homeostasis/efectos de los fármacos , Humanos , Peróxido de Hidrógeno/farmacología , Metformina/farmacología , Ratones , Transportadores de Ácidos Monocarboxílicos/antagonistas & inhibidores , Transportadores de Ácidos Monocarboxílicos/metabolismo , Oxidación-Reducción , Fosforilación Oxidativa/efectos de los fármacos , Unión Proteica , Proteínas Proto-Oncogénicas c-myc/genética , Simportadores/antagonistas & inhibidores , Simportadores/metabolismo , Transcripción Genética
9.
ACS Med Chem Lett ; 4(12): 1244-1248, 2013 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-24639892

RESUMEN

A synthesis of C11-desmethoxy soraphen A1α is described that proceeds in just 14 steps from readily available starting materials. This natural product analog was identified as a target of interest in a program aimed at identifying novel natural product-inspired inhibitors of acetyl-CoA carboxylase (ACC) as potential anticancer therapeutics. While describing the most efficient synthesis of a soraphen A1α analog (total syntheses of the natural product have been reported that proceed in 25 to ≥40 linear steps), we also present data supporting the conclusion that C11-heteroatom functionality is a beneficial but unnecessary structural characteristic of soraphen A1α analogs for inhibiting ACC.

10.
PLoS One ; 7(1): e29761, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22238651

RESUMEN

Invadopodia are membrane protrusions that facilitate matrix degradation and cellular invasion. Although lipids have been implicated in several aspects of invadopodia formation, the contributions of de novo fatty acid synthesis and lipogenesis have not been defined. Inhibition of acetyl-CoA carboxylase 1 (ACC1), the committed step of fatty acid synthesis, reduced invadopodia formation in Src-transformed 3T3 (3T3-Src) cells, and also decreased the ability to degrade gelatin. Inhibition of fatty acid synthesis through AMP-activated kinase (AMPK) activation and ACC phosphorylation also decreased invadopodia incidence. The addition of exogenous 16∶0 and 18∶1 fatty acid, products of de novo fatty acid synthesis, restored invadopodia and gelatin degradation to cells with decreased ACC1 activity. Pharmacological inhibition of ACC also altered the phospholipid profile of 3T3-Src cells, with the majority of changes occurring in the phosphatidylcholine (PC) species. Exogenous supplementation with the most abundant PC species, 34∶1 PC, restored invadopodia incidence, the ability to degrade gelatin and the ability to invade through matrigel to cells deficient in ACC1 activity. On the other hand, 30∶0 PC did not restore invadopodia and 36∶2 PC only restored invadopodia incidence and gelatin degradation, but not cellular invasion through matrigel. Pharmacological inhibition of ACC also reduced the ability of MDA-MB-231 breast, Snb19 glioblastoma, and PC-3 prostate cancer cells to invade through matrigel. Invasion of PC-3 cells through matrigel was also restored by 34∶1 PC supplementation. Collectively, the data elucidate the novel metabolic regulation of invadopodia and the invasive process by de novo fatty acid synthesis and lipogenesis.


Asunto(s)
Acetil-CoA Carboxilasa/fisiología , Movimiento Celular/fisiología , Extensiones de la Superficie Celular/metabolismo , Lipogénesis/fisiología , Neoplasias/patología , Células 3T3 , Acetil-CoA Carboxilasa/antagonistas & inhibidores , Acetil-CoA Carboxilasa/genética , Acetil-CoA Carboxilasa/metabolismo , Animales , Adhesión Celular/efectos de los fármacos , Adhesión Celular/genética , Movimiento Celular/efectos de los fármacos , Movimiento Celular/genética , Extensiones de la Superficie Celular/efectos de los fármacos , Extensiones de la Superficie Celular/genética , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Genes src/fisiología , Humanos , Lipogénesis/efectos de los fármacos , Lipogénesis/genética , Masculino , Ratones , Invasividad Neoplásica , Neoplasias/genética , Neoplasias/metabolismo , ARN Interferente Pequeño/farmacología , Células Tumorales Cultivadas
11.
J Strength Cond Res ; 17(4): 652-8, 2003 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-14636096

RESUMEN

This study examined the effects of delayed-onset muscle soreness (DOMS) on selected physiological responses to submaximal exercise. Seven male and four female subjects (Ss) aged 21-37 years completed two submaximal running sessions at an individualized pace corresponding to a blood lactate concentration (bLa) of approximately 2.5 mmol x L(-1). Following the first session (T1), Ss performed a series of lower extremity resistance exercises designed to induce DOMS. Subjects were then retested (T2) 24-30 hours later, during which time all Ss experienced DOMS. Oxygen uptake, heart rate (HR), respiratory exchange ratio, rating of perceived exertion (RPE), and bLa were measured every 6 minutes. Significant trial effects (p < 0.05) were observed for HR and RPE. HR was significantly higher during T1 at minutes 6 and 12 (p < 0.05), and RPE values were significantly higher at T2 during all recording periods (p < 0.05). Results from this study suggest that DOMS does not affect submaximal oxygen uptake. However, DOMS does appear to affect one's perception of effort.


Asunto(s)
Músculo Esquelético/fisiopatología , Dolor/fisiopatología , Carrera/fisiología , Adulto , Análisis de Varianza , Femenino , Humanos , Masculino , Consumo de Oxígeno , Esfuerzo Físico/fisiología , Factores de Tiempo
12.
J Hand Ther ; 16(4): 305-10, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-14605647

RESUMEN

The purpose of this study was to develop a tape measure method to assess the size of the hand and wrist. This tape measure method was designed to be readily performed, easily administered, reliable, and valid compared with water volumetry. The study sample included 50 normal consenting volunteers. Two examiners measured each hand of each subject three times, alternating hands between measurements. In the second phase of the study, the same two examiners measured both hands of the subjects using the traditional water volumetry method. The intraclass correlation coefficients for intra- and interater reliability obtained were 0.99. Pearson product-moment correlation values between the figure-of-eight tape measure and the water volumetry method for the two examiners were 0.94 and 0.95, respectively. The figure-of-eight method demonstrated excellent reliability and concurrent validity compared with the water volumetry method. These results support the application of the figure-of-eight method as a reliable and valid evaluation tool for the assessment of hand and wrist size.


Asunto(s)
Antropometría/métodos , Mano/anatomía & histología , Adulto , Antropometría/instrumentación , Interpretación Estadística de Datos , Edema/diagnóstico , Femenino , Humanos , Masculino , Reproducibilidad de los Resultados , Agua
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