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1.
Sci Total Environ ; 838(Pt 2): 155968, 2022 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-35584753

RESUMEN

High-altitude wetlands of the Central Andes, locally known as bofedales, provide important ecosystem services, particularly carbon storage, forage provisioning, and water regulation. Local communities have artificially expanded bofedales by irrigating surrounding grasslands to maximise areas for alpaca grazing. Despite their importance, biophysical processes of both natural and artificial bofedales are still poorly studied, which hinders the development of adequate management and conservation strategies. We analyse and compare the vegetation composition, hydrological variables, groundwater chemistry, and soil characteristics of a natural and an artificial bofedal of at least 10 years old in southern Peru, to understand their interrelations and the consequences for ecosystem service provisioning. We do not find statistically significant differences in the soil, water, and vegetation characteristics. Soil organic carbon (SOC) content, which we use as a proxy for carbon storage, is negatively correlated to dissolved oxygen, pH, and soil water temperature. In addition, Non-Metric Multidimensional Scaling analysis shows a positive relation between plant community composition, SOC content, and water electric conductivity. Our results suggest a three-way interaction between hydrological, soil, and vegetation characteristics in the natural bofedal, which also holds for the artificial bofedal. Vegetation cover of two of the most highly nutritious species for alpaca, Lachemilla diplophylla and Lilaeopsis macloviana with 19-22% of crude protein, are weakly or not correlated to environmental variables, suggesting grazing might be obscuring these potential relationships. Given the high economic importance of alpaca breeding for local communities, expanding bofedales artificially appears an effective strategy to enhance their ecosystem services with minimal impact on the ecohydrological properties of bofedales.


Asunto(s)
Ecosistema , Humedales , Carbono/metabolismo , Fitomejoramiento , Suelo/química , Agua
2.
Environ Sci Pollut Res Int ; 28(16): 20624-20636, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33405140

RESUMEN

Glycine max (L.) Merr. (soybean) crop plants have been found to have high lead (Pb) levels in aerial organs; however, knowledge about the processes involved in the incorporation, and subsequent translocation and accumulation of the metal in the plants is scarce. Considering the toxicity of this heavy metal, the aim of the present study was to evaluate Pb uptake and translocation, and their toxic effects on soybean seedlings via experiments of ionic competition with Ca2+ (2.5 mM, Ca:Pb 1:1) and alteration of the transpiration flow [0.25 mM Pb(NO3)2]. The following variables were analyzed: biomass, leaf area (morphological parameters), photosynthetic efficiency, biochemical response (considered physiological stress markers: antioxidant power, chlorophylls, carotenoids, starch, proteins, sugars, and malondialdehyde), and Pb content. Results showed that soybean seedlings can accumulate high Pb concentration in its organs; however, in general, no morpho-physiological Pb stress symptoms were observed, except for lipid peroxidation and antioxidant power. The treatment with Ca ions was not effective in reducing Pb entry into root over time when both Ca and Pb where present in the grow solution. Alteration of the transpiration rate in soybean showed that the air flow increased the consumption of solutions, regardless of the treatments. However, Pb accumulation was lower in seedlings exposed to air flow, indicating a selective exclusion of the metal in the solution. In both experiments, soybean seedlings showed to be tolerant to high Pb concentrations.


Asunto(s)
Glycine max , Plantones , Clorofila , Plomo , Hojas de la Planta , Raíces de Plantas
3.
J Mol Endocrinol ; 66(1): 23-34, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33151902

RESUMEN

White adipose tissue (WAT) browning is a potent mechanism to dissipate energy as heat and, thus, its activation constitutes a promise therapeutic approach to obesity. We previously reported the melanocortin α-melanocyte stimulating hormone (α-MSH) ability to increase the number of beige cells in subcutaneous inguinal WAT (ingWAT) in high fat diet (HFD)-fed mice. The current study examined the browning effect of intraperitoneally administered α-MSH on diverse fat depots from mice fed with HFD or standard rodent diet (SD). For this, mRNA expression of browning hallmark genes was quantified concomitantly with histological examination of the adipose tissue samples (epidydimal (eWAT), mesenteric (mWAT), retroperitoneal (rpWAT) or ingWAT). As well, α-MSH impact on body weight, serum profile, WAT mass and lipolytic rates were evaluated. In the visceral depots mWAT, eWAT and rpWAT from HFD-fed mice, α-MSH was not able to induce a browning mechanism. Surprisingly, in SD-fed mice, α-MSH decreased the expression of several beige-specific genes in rpWAT and promoted an increase of the size of lipid droplets. No browning effect was observed in ingWAT from SD-fed mice. We also verified that HFD ingestion per se stimulated the browning mechanisms in rpWAT, but not in mWAT and eWAT. In conclusion, the fat depots from diverse anatomical locations respond differently to α-MSH treatment when exposed to different diets.


Asunto(s)
Tejido Adiposo Pardo/metabolismo , Tejido Adiposo Blanco/metabolismo , Adiposidad/genética , alfa-MSH/genética , Animales , Peso Corporal , Dieta Alta en Grasa , Regulación de la Expresión Génica , Melanocortinas/genética , Melanocortinas/metabolismo , Ratones , Obesidad/etiología , Obesidad/metabolismo , Especificidad de Órganos , alfa-MSH/metabolismo
4.
Chemosphere ; 269: 128732, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33143889

RESUMEN

Phytoremediation, especially phytoextraction, is a good alternative for remediation of soils contaminated with heavy metals. This method requires selection of species for their tolerance, high accumulation levels in harvestable parts, and high biomass production. Bidens pilosa L. has been reported as tolerant to and potentially hyperaccumulator of several heavy metals, including Pb, but with variable results in terms of effectiveness. The aim of this study was to analyse the intra- and interpopulation variability of B. pilosa in response to Pb in individuals from two populations: one historically exposed to Pb and another with no history of exposure. Bidens pilosa L. presented tolerance to Pb pollution in soil, evidenced in a higher survival rate, a better antioxidant response, and an efficient reduction in cell membrane damage mainly due to history of exposure. The period of exposure (30 years) was not long enough to obtain a B. pilosa population that provides seeds for phytoextraction projects, since the average value of total extraction was relatively low. Collecting seeds from a historically exposed population will provide some suitable individuals with Pb accumulation and translocation capabilities, but not a sufficient amount to conduct a large phytoremediation project. The individual accumulator profile of B. pilosa is not related to the physiological behaviour or to the Pb entry into the vascular bundle in root, but to the incorporation of other heavy metals that are micronutrients.


Asunto(s)
Bidens , Metales Pesados , Contaminantes del Suelo , Biodegradación Ambiental , Humanos , Plomo , Suelo , Contaminantes del Suelo/análisis
5.
Int J Obes (Lond) ; 43(5): 1058-1069, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30018312

RESUMEN

BACKGROUND/OBJECTIVES: The browning of white adipose tissue (WAT) has been in the spotlight during the last years, becoming an attractive approach to combat obesity. Melanocortin neuropeptides, such as α-melanocyte-stimulating hormone (α-MSH), are well-known regulators of appetite at the central nervous system, but its role in adipocyte metabolism is poorly elucidated. This study sought to verify if α-MSH can induce transdifferentiation of white to brown/beige adipocytes and to determine whether it can ameliorate the obesity phenotype. METHODS: The browning effect of α-MSH was determined in isolated adipocytes using the 3T3-L1 cell line and in inguinal subcutaneous adipose tissue (ingWAT) of diet-induced obese (DIO) mice by quantifying the expression of browning hallmark genes, oxygen consumption, and mitochondrial biogenesis. α-MSH protection from diet-induced obesity was evaluated by analyzing mice body weight, fat mass, and lipid and glucose serum profiles. RESULTS: Here, we report that α-MSH activates a thermogenic gene program and increases the mitochondrial respiratory rate in 3T3-L1 adipocytes and ingWAT of DIO mice. Without affecting food intake, peripheral administration of α-MSH decreases body weight and ingWAT mass, promoting a significant rise in the number of smaller adipocytes, whereas it lowered the larger ones. Additionally, there was an increase in the mass of brown adipose tissue. Browning activation occurs concomitantly with improvement on serum lipid profile, insulin resistance, and glucose homeostasis. CONCLUSIONS: This study highlights the anti-obesity properties of melanocortins by promoting ingWAT browning and provides new perspectives for future designing of more effective therapeutic strategies.


Asunto(s)
Adipocitos/metabolismo , Tejido Adiposo Beige/efectos de los fármacos , Tejido Adiposo Pardo/efectos de los fármacos , Tejido Adiposo Blanco/efectos de los fármacos , Melanocortinas/farmacología , Obesidad/prevención & control , Termogénesis/efectos de los fármacos , Células 3T3-L1 , Adipocitos/efectos de los fármacos , Tejido Adiposo Beige/metabolismo , Tejido Adiposo Pardo/metabolismo , Tejido Adiposo Blanco/metabolismo , Animales , Células Cultivadas , Dieta Alta en Grasa , Ratones , Ratones Endogámicos C57BL , Obesidad/metabolismo , Termogénesis/fisiología
6.
Br J Haematol ; 182(4): 534-541, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29978453

RESUMEN

The Grupo Español de Linfomas y Trasplantes de Médula Ósea International Prognostic Index (GELTAMO-IPI) stratifies four risk groups in diffuse large B cell lymphoma (DLBCL) patients treated with immunochaemotherapy: low (LR), low-intermediate (LIR), high-intermediate (HIR), and high (HR). The present study explores the effect of GELTAMO-IPI in the DLBCL subtypes defined by the immunohistochaemistry-based Hans algorithm, Germinal Centre B (GCB) and non-GCB. A multivariate Cox regression model including GELTAMO-IPI risk groups, cell of origin (COO) subtypes and their product was developed to evaluate interaction between the two variables. The COO subtype was available in 839 patients (380 GCB; 459 non-GCB) and both the GELTAMO-IPI and the COO subtype in 780 (353 GCB; 427 non-GCB). There were no differences in 5-year overall survival (OS) between the two subtypes. The Cox model revealed interaction between the GELTAMO-IPI risk groups and the COO subtypes (P = 0·005), indicating that GELTAMO-IPI has a different effect in the two subtypes. Three risk groups were stratified in both COO subtypes: in the GCB subtype, LR, LIR and the combined HIR+HR had 5-year OS of 100%, 75% and 52%, respectively. In the non-GCB subtype, LR, the combined LIR+HIR and HR had a 5-year OS of, 97%, 82% and 35% respectively. GELTAMO-IPI identifies a genuine poor outcome group of patients in the DLBCL non-GCB subtype.


Asunto(s)
Algoritmos , Centro Germinal , Linfoma de Células B Grandes Difuso , Adulto , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Supervivencia sin Enfermedad , Femenino , Centro Germinal/metabolismo , Centro Germinal/patología , Humanos , Inmunoterapia , Linfoma de Células B Grandes Difuso/metabolismo , Linfoma de Células B Grandes Difuso/mortalidad , Linfoma de Células B Grandes Difuso/patología , Linfoma de Células B Grandes Difuso/terapia , Masculino , Persona de Mediana Edad , Pronóstico , Medición de Riesgo , Factores de Riesgo , Tasa de Supervivencia
7.
Br J Haematol ; 176(6): 918-928, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-28106247

RESUMEN

The study included 1848 diffuse large B-cell lymphoma (DLBCL)patients treated with chemotherapy/rituximab. The aims were to validate the National Comprehensive Cancer Network International Prognostic Index (NCCN-IPI) and explore the effect of adding high Beta-2 microglobulin (ß2M), primary extranodal presentation and intense treatment to the NCCN-IPI variables in order to develop an improved index. Comparing survival curves, NCCN-IPI discriminated better than IPI, separating four risk groups with 5-year overall survival rates of 93%, 83%, 67% and 49%, but failing to identify a true high-risk population. For the second aim the series was split into training and validation cohorts: in the former the multivariate model identified age, lactate dehydrogenase, Eastern Cooperative Oncology Group performance status, Stage III-IV, and ß2M as independently significant, whereas the NCCN-IPI-selected extranodal sites, primary extranodal presentation and intense treatments were not. These results were confirmed in the validation cohort. The Grupo Español de Linfomas/Trasplante de Médula ósea (GELTAMO)-IPI developed here, with 7 points, significantly separated four risk groups (0, 1-3, 4 or ≥5 points) with 11%, 58%, 17% and 14% of patients, and 5-year overall survival rates of 93%, 79%, 66% and 39%, respectively. In the comparison GELTAMO IPI discriminated better than the NCCN-IPI. In conclusion, GELTAMO-IPI is more accurate than the NCCN-IPI and has statistical and practical advantages in that the better discrimination identifies an authentic high-risk group and is not influenced by primary extranodal presentation or treatments of different intensity.


Asunto(s)
Linfoma de Células B Grandes Difuso/sangre , Linfoma de Células B Grandes Difuso/mortalidad , Microglobulina beta-2/sangre , Adulto , Anciano , Anciano de 80 o más Años , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Biomarcadores , Femenino , Estudios de Seguimiento , Humanos , Estimación de Kaplan-Meier , Linfoma de Células B Grandes Difuso/diagnóstico , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Pronóstico , Inducción de Remisión , Reproducibilidad de los Resultados , Resultado del Tratamiento
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