Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 210
Filtrar
Más filtros

Intervalo de año de publicación
1.
Breast Cancer Res Treat ; 194(2): 403-412, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35610400

RESUMEN

PURPOSE: PALB2 variants have been scarcely described in Argentinian and Latin-American reports. In this study, we describe molecular and clinical characteristics of PALB2 mutations found in multi-gene panels (MP) from breast-ovarian cancer (BOC) families in different institutions from Argentina. METHODS: We retrospectively identified PALB2 pathogenic (PV) and likely pathogenic (LPV) variants from a cohort of 1905 MP results, provided by one local lab (Heritas) and SITHER (Hereditary Tumor Information System) public database. All patients met hereditary BOC clinical criteria for testing, according to current guidelines. RESULTS: The frequency of PALB2 mutations is 2.78% (53/1905). Forty-eight (90.5%) are PV and five (9.5%) are LPV. Most of the 18 different mutations (89%) are nonsense and frameshift types and 2 variants are novel. One high-rate recurrent PV (Y551*) is present in 43% (23/53) of the unrelated index cases. From the 53 affected carriers, 94% have BC diagnosis with 14% of bilateral cases. BC phenotype is mainly invasive ductal (78%) with 62% of hormone-receptor positive and 22% of triple negative tumors. Self-reported ethnic background of the cohort is West European (66%) and native Latin-American (20%) which is representative of Buenos Aires and other big urban areas of the country. CONCLUSION: This is the first report describing molecular and clinical characteristics of PALB2 carriers in Argentina. Frequency of PALB2 PV in Argentinian HBOC families is higher than in other reported populations. Y551* is a recurrent mutation that seems to be responsible for almost 50% of PALB2 cases.


Asunto(s)
Neoplasias de la Mama , Neoplasias Ováricas , Argentina/epidemiología , Neoplasias de la Mama/epidemiología , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Proteína del Grupo de Complementación N de la Anemia de Fanconi/genética , Femenino , Predisposición Genética a la Enfermedad , Mutación de Línea Germinal , Humanos , Neoplasias Ováricas/epidemiología , Neoplasias Ováricas/genética , Estudios Retrospectivos
2.
Sensors (Basel) ; 23(1)2022 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-36616647

RESUMEN

The roles of emergency responders are challenging and often physically demanding, so it is essential that their duties are performed safely and effectively. In this article, we address real-time bio-signal sensor monitoring for responders in disaster scenarios. In particular, we propose the integration of a set of health monitoring sensors suitable for detecting stress, anxiety and physical fatigue in an Internet of Cooperative Agents architecture for search and rescue (SAR) missions (SAR-IoCA), which allows remote control and communication between human and robotic agents and the mission control center. With this purpose, we performed proof-of-concept experiments with a bio-signal sensor suite worn by firefighters in two high-fidelity SAR exercises. Moreover, we conducted a survey, distributed to end-users through the Fire Brigade consortium of the Provincial Council of Málaga, in order to analyze the firefighters' opinion about biological signals monitoring while on duty. As a result of this methodology, we propose a wearable sensor suite design with the aim of providing some easy-to-wear integrated-sensor garments, which are suitable for emergency worker activity. The article offers discussion of user acceptance, performance results and learned lessons.


Asunto(s)
Bomberos , Robótica , Humanos , Robótica/métodos , Trabajo de Rescate , Comunicación
3.
Proc Natl Acad Sci U S A ; 115(21): 5612-5617, 2018 05 22.
Artículo en Inglés | MEDLINE | ID: mdl-29724856

RESUMEN

Light cues from neighboring vegetation rapidly initiate plant shade-avoidance responses. Despite our detailed knowledge of the early steps of this response, the molecular events under prolonged shade are largely unclear. Here we show that persistent neighbor cues reinforce growth responses in addition to promoting auxin-responsive gene expression in Arabidopsis and soybean. However, while the elevation of auxin levels is well established as an early event, in Arabidopsis, the response to prolonged shade occurs when auxin levels have declined to the prestimulation values. Remarkably, the sustained low activity of phytochrome B under prolonged shade led to (i) decreased levels of PHYTOCHROME INTERACTING FACTOR 4 (PIF4) in the cotyledons (the organs that supply auxin) along with increased levels in the vascular tissues of the stem, (ii) elevated expression of the PIF4 targets INDOLE-3-ACETIC ACID 19 (IAA19) and IAA29, which in turn reduced the expression of the growth-repressive IAA17 regulator, (iii) reduced abundance of AUXIN RESPONSE FACTOR 6, (iv) reduced expression of MIR393 and increased abundance of its targets, the auxin receptors, and (v) elevated auxin signaling as indicated by molecular markers. Mathematical and genetic analyses support the physiological role of this system-level rearrangement. We propose that prolonged shade rewires the connectivity between light and auxin signaling to sustain shade avoidance without enhanced auxin levels.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Ácidos Indolacéticos/farmacología , Luz , Fitocromo/metabolismo , Fenómenos Fisiológicos de las Plantas , Arabidopsis/efectos de los fármacos , Arabidopsis/crecimiento & desarrollo , Proteínas de Arabidopsis/genética , Fitocromo/genética , Reguladores del Crecimiento de las Plantas/farmacología , Transducción de Señal
4.
World J Microbiol Biotechnol ; 37(10): 166, 2021 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-34463818

RESUMEN

Central-Andean Ecosystems (between 2000 and 6000 m above sea level (masl) are typical arid-to-semiarid environments suffering from the highest total solar and ultraviolet-B radiation on the planet but displaying numerous salt flats and shallow lakes. Andean microbial ecosystems isolated from these environments are of exceptional biodiversity enduring multiple severe conditions. Furthermore, the polyextremophilic nature of the microbes in such ecosystems indicates the potential for biotechnological applications. Within this context, the study undertaken used genome mining, physiological and microscopical characterization to reveal the multiresistant profile of Nesterenkonia sp. Act20, an actinobacterium isolated from the soil surrounding Lake Socompa, Salta, Argentina (3570 masl). Ultravioet-B, desiccation, and copper assays revealed the strain's exceptional resistance to all these conditions. Act20's genome presented coding sequences involving resistance to antibiotics, low temperatures, ultraviolet radiation, arsenic, nutrient-limiting conditions, osmotic stress, low atmospheric-oxygen pressure, heavy-metal stress, and toxic fluoride and chlorite. Act20 can also synthesize proteins and natural products such as an insecticide, bacterial cellulose, ectoine, bacterial hemoglobin, and even antibiotics like colicin V and aurachin C. We also found numerous enzymes for animal- and vegetal-biomass degradation and applications in other industrial processes. The resilience of Act20 and its biotechnologic potential were thoroughly demonstrated in this work.


Asunto(s)
Actinobacteria/genética , Actinobacteria/aislamiento & purificación , Suelo/química , Actinobacteria/química , Actinobacteria/clasificación , Argentina , Biotecnología , Ecosistema , Genoma Bacteriano , Genómica , Presión Osmótica , Microbiología del Suelo
5.
Plant J ; 99(1): 7-22, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-30924988

RESUMEN

Shade-intolerant plants respond to the decrease in the red (R) to far-red (FR) light ratio (R:FR) occurring under shade by elongating stems and petioles and by re-positioning leaves, in a race to outcompete neighbors for the sunlight resource. In some annual species, the shade avoidance syndrome (SAS) is accompanied by the early induction of flowering. Anticipated flowering is viewed as a strategy to set seeds before the resources become severely limiting. Little is known about the molecular mechanisms of SAS in perennial forage crops like alfalfa (Medicago sativa). To study SAS in alfalfa, we exposed alfalfa plants to simulated shade by supplementing with FR light. Low R:FR light produced a classical SAS, with increased internode and petiole lengths, but unexpectedly also with delayed flowering. To understand the molecular mechanisms involved in uncoupling SAS from early flowering, we used a transcriptomic approach. The SAS is likely to be mediated by increased expression of msPIF3 and msHB2 in low R:FR light. Constitutive expression of these genes in Arabidopsis led to SAS, including early flowering, strongly suggesting that their roles are conserved. Delayed flowering was likely to be mediated by the downregulation of msSPL3, which promotes flowering in both Arabidopsis and alfalfa. Shade-delayed flowering in alfalfa may be important to extend the vegetative phase under suboptimal light conditions, and thus assure the accumulation of reserves necessary to resume growth after the next season.


Asunto(s)
Flores/fisiología , Luz , Arabidopsis/metabolismo , Arabidopsis/fisiología , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Flores/metabolismo , Regulación de la Expresión Génica de las Plantas , Medicago sativa/metabolismo , Medicago sativa/fisiología
6.
Plant Biotechnol J ; 18(4): 944-954, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31536663

RESUMEN

Alfalfa (Medicago sativa L.) is one of the most important forage crops worldwide. As a perennial, alfalfa is cut several times each year. Farmers face a dilemma: if cut earlier, forage nutritive value is much higher but regrowth is affected and the longevity of the stand is severely compromised. On the other hand, if alfalfa is cut later at full flower, stands persist longer and more biomass may be harvested, but the nutritive value diminishes. Alfalfa is a strict long-day plant. We reasoned that by manipulating the response to photoperiod, we could delay flowering to improve forage quality and widen each harvesting window, facilitating management. With this aim, we functionally characterized the FLOWERING LOCUS T family of genes, represented by five members: MsFTa1, MsFTa2, MsFTb1, MsFTb2 and MsFTc. The expression of MsFTa1 correlated with photoperiodic flowering and its down-regulation led to severe delayed flowering. Altogether, with late flowering, low expression of MsFTa1 led to changes in plant architecture resulting in increased leaf to stem biomass ratios and forage digestibility. By manipulating photoperiodic flowering, we were able to improve the quality of alfalfa forage and management, which may allow farmers to cut alfalfa of high nutritive value without compromising stand persistence.


Asunto(s)
Regulación de la Expresión Génica de las Plantas , Medicago sativa/genética , Valor Nutritivo , Proteínas de Plantas/genética , Biomasa , Regulación hacia Abajo , Flores/fisiología , Medicago sativa/química , Fotoperiodo
7.
Am J Phys Anthropol ; 173(4): 709-720, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32808278

RESUMEN

OBJECTIVES: The aim of this work is to explore the maternal genetic diversity of hunter-gatherers of the southern Tierra del Fuego, specifically the north coast of Beagle Channel, the Península Mitre, and Isla de los Estados through ancient mitochondrial DNA analysis. MATERIALS AND METHODS: The hypervariable regions 1 and 2 of the mitochondrial genome of five individuals from the north coast of Beagle Channel, six individuals from Península Mitre, and one individual from Isla de los Estados were analyzed. Through diversity statistics, Analysis of Molecular Variance (AMOVA), and Median Joining networks analyses, maternal relationships in the region were evaluated and phylogenetic similarities between ancient and contemporary populations of Tierra del Fuego were determined. RESULTS: The mitochondrial DNA lineages from the ancient individuals analyzed reveals the presence of subclades C1b and D1g. Pattern of decreasing genetic diversity toward the South is observed. The AMOVAs performed found no statistically significant differences between individuals of the north coast of Beagle Channel and Península Mitre-Isla de los Estados, and modern Yámana populations. Median joining network of haplotypes of clades C1 and D1g, show the same results. DISCUSSION: Ethnohistoric and ethnographic records of Península Mitre show that this region was occupied during the 19th century by Haush or Manekenk populations, although their biological, cultural, and subsistence characterization is unclear. We explore their maternal lineages and encounter low levels of genetic diversity and the absence of population differentiation with modern Yámana groups. We suggest that Península Mitre-Isla de los Estado was part of the same hunting and gathering populations as those of the Beagle Channel.


Asunto(s)
ADN Mitocondrial , Indígenas Sudamericanos , Adulto , Argentina , ADN Mitocondrial/clasificación , ADN Mitocondrial/genética , Femenino , Variación Genética/genética , Genética de Población , Haplotipos/genética , Historia Antigua , Humanos , Indígenas Sudamericanos/clasificación , Indígenas Sudamericanos/genética , Indígenas Sudamericanos/historia , Masculino , Persona de Mediana Edad , Adulto Joven
8.
Ann Hepatol ; 18(3): 480-487, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31023615

RESUMEN

INTRODUCTION AND AIM: A pro-oncogenic intestinal microbiome was observed in murine models; however, no specific microbiome in patients with hepatocellular carcinoma (HCC) has been reported. We aimed to compare the gut microbiome found in cirrhotic patients with or without HCC. MATERIALS AND METHODS: From 407 patients with Child Pugh A/B cirrhosis prospectively followed, 25 with HCC (cases) were matched with 25 without HCC (wo-HCC) in a 1:1 ratio according to age, gender, etiology, Child Pugh and severity of portal hypertension. In addition, results were also compared with 25 healthy subjects. Fecal stool samples were sequenced for the V3-V4 region of the microbial 16S rRNA (Illumina MiSeq Platform). Plasma cytokines were quantified including interleukin-6 (IL-6) and tumor necrosis factor α (TNF-α). RESULTS: We found a differential abundance in family members of Firmicutes with a 3-fold increase of Erysipelotrichaceae and a 5-fold decrease in family Leuconostocaceae in HCC when compared to wo-HCC controls. Genus Fusobacterium was found to be 5-fold decreased in HCC vs wo-HCC. The ratio bacteriodes/prevotella was increased in HCC. Three operational taxonomic units (OTUs), genus Odoribacter and Butyricimonas were more abundant in HCC, whereas a decreased abundance in Lachnospiraceae family genus Dorea was observed in HCC patients. A Random Forest model trained with differential abundant taxa correctly classified HCC individuals. This pattern was associated with an inflammatory milieu with a putative increased activation of NOD-like receptor pathways. CONCLUSION: We found a pattern of microbiome linked to inflammation that could be potentially useful as HCC biomarker after follow-up validation studies.


Asunto(s)
Carcinoma Hepatocelular/microbiología , Citocinas/metabolismo , Microbioma Gastrointestinal , Inflamación/microbiología , Cirrosis Hepática/microbiología , Neoplasias Hepáticas/microbiología , Carcinoma Hepatocelular/complicaciones , Carcinoma Hepatocelular/diagnóstico , Estudios de Casos y Controles , Heces/microbiología , Femenino , Estudios de Seguimiento , Humanos , Inflamación/diagnóstico , Inflamación/metabolismo , Cirrosis Hepática/complicaciones , Cirrosis Hepática/diagnóstico , Neoplasias Hepáticas/complicaciones , Neoplasias Hepáticas/diagnóstico , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Tomografía Computarizada por Rayos X
10.
BMC Genomics ; 18(1): 445, 2017 06 06.
Artículo en Inglés | MEDLINE | ID: mdl-28587624

RESUMEN

BACKGROUND: Several archaeal species from the order Sulfolobales are interesting from the biotechnological point of view due to their biomining capacities. Within this group, the genus Acidianus contains four biomining species (from ten known Acidianus species), but none of these have their genome sequenced. To get insights into the genetic potential and metabolic pathways involved in the biomining activity of this group, we sequenced the genome of Acidianus copahuensis ALE1 strain, a novel thermoacidophilic crenarchaeon (optimum growth: 75 °C, pH 3) isolated from the volcanic geothermal area of Copahue at Neuquén province in Argentina. Previous experimental characterization of A. copahuensis revealed a high biomining potential, exhibited as high oxidation activity of sulfur and sulfur compounds, ferrous iron and sulfide minerals (e.g.: pyrite). This strain is also autotrophic and tolerant to heavy metals, thus, it can grow under adverse conditions for most forms of life with a low nutrient demand, conditions that are commonly found in mining environments. RESULTS: In this work we analyzed the genome of Acidianus copahuensis and describe the genetic pathways involved in biomining processes. We identified the enzymes that are most likely involved in growth on sulfur and ferrous iron oxidation as well as those involved in autotrophic carbon fixation. We also found that A. copahuensis genome gathers different features that are only present in particular lineages or species from the order Sulfolobales, some of which are involved in biomining. We found that although most of its genes (81%) were found in at least one other Sulfolobales species, it is not specifically closer to any particular species (60-70% of proteins shared with each of them). Although almost one fifth of A. copahuensis proteins are not found in any other Sulfolobales species, most of them corresponded to hypothetical proteins from uncharacterized metabolisms. CONCLUSION: In this work we identified the genes responsible for the biomining metabolisms that we have previously observed experimentally. We provide a landscape of the metabolic potentials of this strain in the context of Sulfolobales and propose various pathways and cellular processes not yet fully understood that can use A. copahuensis as an experimental model to further understand the fascinating biology of thermoacidophilic biomining archaea.


Asunto(s)
Acidianus/genética , Acidianus/metabolismo , Genómica , Minería , Acidianus/efectos de los fármacos , Ciclo del Carbono/genética , Hierro/metabolismo , Metales/farmacología , Oxidorreductasas/metabolismo , Azufre/metabolismo , Temperatura
12.
Biochem J ; 466(1): 163-76, 2015 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-25437352

RESUMEN

Glucocorticoids play an important role in the treatment of inflammation and immune disorders, despite side effects, which include metabolic derangements such as central adiposity. These studies examine the role of protein phosphatase 5 (Ppp5) in glucocorticoid receptor (GR) complexes which mediate response to glucocorticoids. Mice homozygous for inactivated Ppp5 (Ppp5D274A/D274A) exhibit decreased adipose tissue surrounding the gonads and kidneys compared with wild-type mice. Adipocyte size is smaller, more preadipocytes/stromal cell are present in their gonadal fat tissue and differentiation of preadipocytes to adipocytes is retarded. Glucocorticoid levels are raised and the GR is hyperphosphorylated in adipose tissue of Ppp5D274A/D274A mice at Ser212 and Ser220 (orthologous to human Ser203 and Ser211) in the absence of glucocorticoids. Preadipocyte cultures from Ppp5D274A/D274A mice show decreased down regulation of Delta-like protein-1/preadipocyte factor-1, hyperphosphorylation of extra-cellular signal regulated kinase 2 (ERK2) and increased concentration of (sex determining region Y)-box 9 (SOX9), changes in a pathway essential for preadipocyte differentiation, which leads to decreased concentrations of the transcription factors CEBPß and CEBPα necessary for the later stages of adipogenesis. The data indicate that Ppp5 plays a crucial role in modifying GR-mediated initiation of adipose tissue differentiation, suggesting that inhibition of Ppp5 may potentially be beneficial to prevent obesity during glucocorticoid treatment.


Asunto(s)
Adipocitos/metabolismo , Adipogénesis/genética , Tejido Adiposo/metabolismo , Proteínas Nucleares/genética , Fosfoproteínas Fosfatasas/genética , Receptores de Glucocorticoides/genética , Adipocitos/citología , Adipocitos/efectos de los fármacos , Tejido Adiposo/citología , Tejido Adiposo/efectos de los fármacos , Animales , Proteína beta Potenciadora de Unión a CCAAT/genética , Proteína beta Potenciadora de Unión a CCAAT/metabolismo , Proteínas Potenciadoras de Unión a CCAAT/genética , Proteínas Potenciadoras de Unión a CCAAT/metabolismo , Diferenciación Celular , Dexametasona/farmacología , Femenino , Regulación de la Expresión Génica , Gónadas/citología , Gónadas/efectos de los fármacos , Gónadas/metabolismo , Proteínas HSP90 de Choque Térmico/genética , Proteínas HSP90 de Choque Térmico/metabolismo , Péptidos y Proteínas de Señalización Intracelular/genética , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Riñón/citología , Riñón/efectos de los fármacos , Riñón/metabolismo , Masculino , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Ratones , Ratones Noqueados , Proteína Quinasa 1 Activada por Mitógenos/genética , Proteína Quinasa 1 Activada por Mitógenos/metabolismo , Proteínas Nucleares/deficiencia , PPAR gamma/genética , PPAR gamma/metabolismo , Fosfoproteínas Fosfatasas/deficiencia , Fosforilación , Receptores de Glucocorticoides/metabolismo , Factor de Transcripción SOX9/genética , Factor de Transcripción SOX9/metabolismo , Transducción de Señal
13.
Mediators Inflamm ; 2013: 953841, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24453432

RESUMEN

Excessive energy management leads to low-grade, chronic inflammation, which is a significant factor predicting noncommunicable diseases. In turn, inflammation, oxidation, and metabolism are associated with the course of these diseases; mitochondrial dysfunction seems to be at the crossroads of mutual relationships. The migration of immune cells during inflammation is governed by the interaction between chemokines and chemokine receptors. Chemokines, especially C-C-chemokine ligand 2 (CCL2), have a variety of additional functions that are involved in the maintenance of normal metabolism. It is our hypothesis that a ubiquitous and continuous secretion of CCL2 may represent an animal model of low-grade chronic inflammation that, in the presence of an energy surplus, could help to ascertain the afore-mentioned relationships and/or to search for specific therapeutic approaches. Here, we present preliminary data on a mouse model created by using targeted gene knock-in technology to integrate an additional copy of the CCl2 gene in the Gt(ROSA)26Sor locus of the mouse genome via homologous recombination in embryonic stem cells. Short-term dietary manipulations were assessed and the findings include metabolic disturbances, premature death, and the manipulation of macrophage plasticity and autophagy. These results raise a number of mechanistic questions for future study.


Asunto(s)
Quimiocina CCL2/fisiología , Ingestión de Energía , Inflamación/etiología , Adipocitos/patología , Animales , Autofagia , Peso Corporal , Quimiocina CCL2/genética , Citocinas/genética , Dieta Alta en Grasa , Glucosa/metabolismo , Metabolismo de los Lípidos , Macrófagos/inmunología , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Serina-Treonina Quinasas TOR/fisiología
14.
Br J Cancer ; 106(8): 1406-14, 2012 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-22491422

RESUMEN

BACKGROUND: In addition to the mutational status of KRAS, the epidermal growth factor receptor (EGFR) ligands amphiregulin (AREG) and epiregulin (EREG) might function as bona fide biomarkers of cetuximab (Ctx) sensitivity for most EGFR-driven carcinomas. METHODS: Lentivirus-delivered small hairpin RNAs were employed to specifically reduce AREG or EREG gene expression in wild-type KRAS A431 squamous cell carcinoma cells. Colony-forming assays were used to monitor the impact of AREG and EREG knockdown on Ctx efficacy. Amphiregulin and EREG protein expression levels were assessed by quantitative ELISA in parental A431 cells and in pooled populations of A431 cells adapted to grow in the presence of Ctx. A phosphoproteomic platform was used to measure the relative level of phosphorylation of 42 distinct receptor tyrosine kinases before and after the acquisition of resistance to Ctx. RESULTS: Stable gene silencing of either ligand was found to notably reduce the expression of the other ligand. Parental A431 cells with normal expression levels of AREG/EREG exhibited significantly increased growth inhibition in response to Ctx, compared with derivatives that are engineered to produce minimal AREG/EREG. The parental A431 cells acutely treated with Ctx exhibited reduced basal expression levels of AREG/EREG. Pooled populations of Ctx-resistant A431 cells expressed significantly lower levels of AREG/EREG and were insensitive to the downregulatory effects of Ctx. Phosphoproteomic screen identified a remarkable hyperactivation of FGFR3 in Ctx-resistant A431 cells, which gained sensitivity to the cytotoxic and apoptotic effects of the FGFR3 TK inhibitor PD173074. The A431 parental cells acutely treated with Ctx rapidly activated FGFR3 and their concomitant exposure to Ctx and PD173074 resulted in synergistic apoptosis. CONCLUSION: Cross-suppression of AREG/EREG expression may explain the tight co-expression of AREG and EREG, as well as their tendency to be more highly expressed than other EGFR ligands to determine Ctx efficacy. The positive selection for Ctx-resistant tumour cells exhibiting AREG/EREG cross-suppression may have an important role in the emergence of Ctx resistance. As de-repression of FGFR3 activity rapidly replaces the loss of EGFR-ligand signalling in terms of cell proliferation and survival, combinations of Ctx and FGFR3-targeted drugs may be a valuable strategy to enhance the efficacy of single Ctx while preventing or delaying acquired resistance to Ctx.


Asunto(s)
Anticuerpos Monoclonales/farmacología , Resistencia a Antineoplásicos/efectos de los fármacos , Factor de Crecimiento Epidérmico/antagonistas & inhibidores , Receptores ErbB/metabolismo , Glicoproteínas/antagonistas & inhibidores , Receptor Tipo 3 de Factor de Crecimiento de Fibroblastos/metabolismo , Transducción de Señal/efectos de los fármacos , Neoplasias Cutáneas/patología , Anfirregulina , Anticuerpos Monoclonales Humanizados , Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Cetuximab , Familia de Proteínas EGF , Factor de Crecimiento Epidérmico/biosíntesis , Factor de Crecimiento Epidérmico/genética , Epirregulina , Técnicas de Silenciamiento del Gen , Glicoproteínas/biosíntesis , Glicoproteínas/genética , Humanos , Péptidos y Proteínas de Señalización Intercelular/biosíntesis , Péptidos y Proteínas de Señalización Intercelular/genética , Ligandos , Pirimidinas/farmacología , Neoplasias Cutáneas/tratamiento farmacológico , Relación Estructura-Actividad , Células Tumorales Cultivadas
15.
Invest New Drugs ; 30(2): 846-52, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21161326

RESUMEN

Molecular mechanisms other than activating KRAS mutations should underlie the occurrence of weaker versus stronger responses to cetuximab (CTX) in EGFR-dependent carcinomas with either an intact KRAS signaling or in which KRAS mutations do not predict CTX efficacy. We hypothesized that KRAS wild-type (WT) tumor cell-line models chronically adapted to grow in the presence of CTX could be interrogated to establish if the positive predictive value of the mRNAs coding for the EGFR ligands amphiregulin (AR) and epiregulin (EPI) could be significantly altered during and/or after treatment with CTX. Gene expression analyses using real-time (kinetic) RT-PCR were performed to monitor the transcriptional evolution of EGFR ligands EGF, TGFα, AR, BTC, EPI, NRG and HB-EGF in experimental modes induced to exhibit acquired resistance to the mono-HER1 inhibitor CTX, the mono-HER2 inhibitor trastuzumab (Tzb) or the dual HER1/HER2 inhibitor lapatinib (LPT). Gene expression signatures for EGFR ligands distinctively related to the occurrence of unresponsiveness to CTX, Tzb or LPT, with minimal overlap between them. CTX's molecular functioning largely depended on the overproduction of the mRNAs coding for the EGFR ligands AR and EPI. Thus, a dramatic down-regulation of AR/EPI mRNA expression occurred upon loss of CTX efficacy in EGFR-positive tumor cells with an intact regulation of RAS signaling. Unlike KRAS mutations, which are informative of unresponsiveness to CTX solely in mCRC, our hypothesis-generating data suggest that expression status of AR and EPI mRNAs might be evaluated as dynamic predictors of response in KRAS WT patients receiving any CTX-based therapy.


Asunto(s)
Anticuerpos Monoclonales/farmacología , Antineoplásicos/farmacología , Biomarcadores de Tumor/metabolismo , Carcinoma de Células Escamosas/genética , Factor de Crecimiento Epidérmico/genética , Glicoproteínas/genética , Péptidos y Proteínas de Señalización Intercelular/genética , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Proto-Oncogénicas/genética , ARN Mensajero/metabolismo , Neoplasias de la Vulva/genética , Proteínas ras/genética , Anfirregulina , Anticuerpos Monoclonales Humanizados , Carcinoma de Células Escamosas/enzimología , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patología , Línea Celular Tumoral , Cetuximab , Resistencia a Antineoplásicos/genética , Familia de Proteínas EGF , Epirregulina , Receptores ErbB/antagonistas & inhibidores , Receptores ErbB/genética , Receptores ErbB/metabolismo , Femenino , Perfilación de la Expresión Génica/métodos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Ligandos , Proteínas Proto-Oncogénicas p21(ras) , Reacción en Cadena en Tiempo Real de la Polimerasa , Receptor ErbB-2/antagonistas & inhibidores , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismo , Factores de Tiempo , Regulación hacia Arriba , Neoplasias de la Vulva/enzimología , Neoplasias de la Vulva/metabolismo , Neoplasias de la Vulva/patología
16.
Mol Biol Rep ; 39(6): 6655-60, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22302390

RESUMEN

Mitochondrial disorders are a frequent cause of neurological disability affecting children and adults. Traditionally, molecular diagnosis of mitochondrial diseases was mostly accomplished by the use of Sanger sequencing and PCR-RFLP. However, there are particular drawbacks associated with the use of these methods. Recent multidisciplinary advances have led to new sequencing methods that may overcome these limitations. Our goal was to explore the use of a next generation sequencing platform in the molecular diagnosis of mitochondrial diseases reporting our findings in adult patients that present with a clinical-pathological diagnosis of a mitochondrial encephalomyopathy. Complete genomic sequences of mitochondrial DNA were obtained by 454 massive pyrosequencing from blood samples. The analysis of these sequences allowed us to identify two diagnostic pathogenic mutations and 74 homoplasmic polymorphisms, useful for obtaining high-resolution mitochondrial haplogroups. In summary, molecular diagnosis of mitochondrial disorders could be efficiently done from readily accessible samples, such as blood, with the use of a new sequencing platform.


Asunto(s)
Secuenciación de Nucleótidos de Alto Rendimiento , Enfermedades Mitocondriales/diagnóstico , Adulto , ADN Mitocondrial/genética , Resultado Fatal , Femenino , Marcadores Genéticos , Humanos , Masculino , Enfermedades Mitocondriales/genética , Técnicas de Diagnóstico Molecular , Sensibilidad y Especificidad , Análisis de Secuencia de ADN
17.
Drug Resist Updat ; 14(4-5): 212-23, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21600837

RESUMEN

Ideal oncology drugs would be curative after a short treatment course if they could eliminate epithelium-originated carcinomas at their non-invasive, pre-malignant stages. Such ideal molecules, which are expected to molecularly abrogate all the instrumental mechanisms acquired by migrating cancer stem cells (CSCs) to by-pass tumour suppressor barriers, might already exist. We here illustrate how system biology strategies for repositioning existing FDA-approved drugs may accelerate our therapeutic capacity to eliminate CSC traits in pre-invasive intraepithelial neoplasias. First, we describe a signalling network signature that overrides bioenergetics stress- and oncogene-induced senescence (OIS) phenomena in CSCs residing at pre-invasive lesions. Second, we functionally map the anti-malarial chloroquine and the anti-diabetic metformin ("old drugs") to their recently recognized CSC targets ("new uses") within the network. By discussing the preclinical efficacy of chloroquine and metformin to inhibiting the genesis and self-renewal of CSCs we finally underscore the expected translational impact of the "old drugs-new uses" repurposing strategy to open a new CSC-targeted chemoprevention era.


Asunto(s)
Antineoplásicos/farmacología , Neoplasias de la Mama/tratamiento farmacológico , Carcinoma Intraductal no Infiltrante/tratamiento farmacológico , Cloroquina/farmacología , Reposicionamiento de Medicamentos , Metformina/farmacología , Células Madre Neoplásicas/fisiología , Envejecimiento/patología , Envejecimiento/fisiología , Animales , Antimaláricos/farmacología , Antimaláricos/uso terapéutico , Antineoplásicos/uso terapéutico , Autofagia/genética , Autofagia/fisiología , Neoplasias de la Mama/fisiopatología , Neoplasias de la Mama/prevención & control , Carcinoma Intraductal no Infiltrante/prevención & control , Cloroquina/uso terapéutico , Evaluación Preclínica de Medicamentos , Transición Epitelial-Mesenquimal/efectos de los fármacos , Transición Epitelial-Mesenquimal/genética , Transición Epitelial-Mesenquimal/fisiología , Femenino , Humanos , Hipoglucemiantes/farmacología , Metformina/uso terapéutico , Terapia Molecular Dirigida , Neoplasias/patología , Neoplasias/prevención & control , Células Madre Neoplásicas/patología , Fenotipo , Transducción de Señal , Proteínas de la Superfamilia TGF-beta/agonistas
18.
Cogn Process ; 13 Suppl 1: S351-4, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22806676

RESUMEN

Monocular approaches to simultaneous localization and mapping (SLAM) have recently addressed with success the challenging problem of the fast computation of dense reconstructions from a single, moving camera. Thus, if these approaches initially relied on the detection of a reduced set of interest points to estimate the camera position and the map, they are currently able to reconstruct dense maps from a handheld camera while the camera coordinates are simultaneously computed. However, these maps of 3-dimensional points usually remain meaningless, that is, with no memorable items and without providing a way of encoding spatial relationships between objects and paths. In humans and mobile robotics, landmarks play a key role in the internalization of a spatial representation of an environment. They are memorable cues that can serve to define a region of the space or the location of other objects. In a topological representation of the space, landmarks can be identified and located according to its structural, perceptive or semantic significance and distinctiveness. But on the other hand, landmarks may be difficult to be located in a metric representation of the space. Restricted to the domain of visual landmarks, this work describes an approach where the map resulting from a point-based, monocular SLAM is annotated with the semantic information provided by a set of distinguished landmarks. Both features are obtained from the image. Hence, they can be linked by associating to each landmark all those point-based features that are superimposed to the landmark in a given image (key-frame). Visual landmarks will be obtained by means of an object-based, bottom-up attention mechanism, which will extract from the image a set of proto-objects. These proto-objects could not be always associated with natural objects, but they will typically constitute significant parts of these scene objects and can be appropriately annotated with semantic information. Moreover, they will be affine covariant regions, that is, they will be invariant to affine transformation, being detected under different viewing conditions (view-point angle, rotation, scale, etc.). Monocular SLAM will be solved using the accurate parallel tracking and mapping (PTAM) framework by Klein and Murray in Proceedings of IEEE/ACM international symposium on mixed and augmented reality, 2007.


Asunto(s)
Reconocimiento Visual de Modelos/fisiología , Fotograbar/métodos , Reconocimiento en Psicología/fisiología , Detección de Señal Psicológica , Algoritmos , Humanos , Imagenología Tridimensional , Estimulación Luminosa , Grabación en Video
19.
Radiologia ; 54(1): 45-58, 2012.
Artículo en Español | MEDLINE | ID: mdl-22001553

RESUMEN

The outcome of treatment for rectal cancer in recent years has been improved by diverse advances in the field of surgery and in neoadjuvant oncologic therapies. Heald's introduction of the concept of the mesorectum as an anatomical unit (total mesorectal excision) in 1982 and the generalization of preoperative radiochemotherapy have improved the prognosis in a significant number of patients. Owing to these advances, it has become necessary for imaging studies to define a series of prognostic factors for tumors, both before and after neoadjuvant treatment, to make it possible to tailor treatment for individual patients with rectal tumors. On the other hand, the advent of functional and molecular imaging techniques has provided a way to study a series of distinctive tumor characteristics in vivo, including the angiogenesis, metabolism, or cellularity of rectal tumors, and these techniques are making a growing contribution to the prognosis, staging, treatment planning, and evaluation of the response to therapy in patients with rectal cancer.


Asunto(s)
Imagen por Resonancia Magnética , Neoplasias del Recto/patología , Humanos , Neovascularización Patológica , Pronóstico , Neoplasias del Recto/irrigación sanguínea
20.
Front Med (Lausanne) ; 9: 1056374, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36579150

RESUMEN

Background: COVID-19 may present different degrees of severity. Viral infections in patients with rheumatic inflammatory diseases (R-IMID) trend to present more severe disease. However, data comparing the severity of the disease between R-IMID and the general population are scarce. Objectives: To compare predisposing factors, clinical, serological features, and severity of COVID-19 infection in patients with and without R-IMID. Methods: Case-control study in a single University Hospital. We included all consecutive patients with a diagnosis of an R-IMID and COVID-19 infection up to March 31st, 2021. This cohort was compared to patients without R-IMID and not receiving immunosuppressive therapy, matched for sex and age (±5 years). Confirmed infection was defined if a patient had a positive nasopharyngeal swab for SARS-CoV-2. Severity was divided into mild, moderate, severe and critical according to the United States National Institute of Health (NIH) guidelines. Results: We included 274 R-IMID patients (185 women/89 men), mean age 59.1 ± 18 years. More frequent R-IMID were: Rheumatoid arthritis (28.8%), Psoriatic Arthritis (20.1%), axial Spondyloarthritis (12.4%), Polymyalgia Rheumatica (8%) and Systemic Lupus Erythematosus (8%). Hypertension and dyslipidemia were more frequent in patients with R-IMID. Although most of the cases were mild, critical cases and deaths were more frequent in R-IMID. When adjusted by comorbidities, no statistical differences were observed. Conclusion: R-IMID have a very similar clinical presentation when compared to the general population. There is a trend to an increased severity of the disease in patients with R-IMID.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA