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1.
Int J Mol Sci ; 25(9)2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38732231

RESUMEN

Regenerative medicine is an interdisciplinary field aiming at restoring pathologically damaged tissues and whole organs by cell transplantation in combination with proper supporting scaffolds. Gelatine-based ones are very attractive due to their biocompatibility, rapid biodegradability, and lack of immunogenicity. Gelatine-based composite hydrogels, containing strengthening agents to improve their modest mechanical properties, have been demonstrated to act as extracellular matrices (ECMs), thus playing a critical role in "organ manufacturing". Inspired by the lysyl oxidase (LO)-mediated process of crosslinking, which occurs in nature to reinforce collagen, we have recently developed a versatile protocol to crosslink gelatine B (Gel B) in the presence or absence of LO, using properly synthesized polystyrene- and polyacrylic-based copolymers containing the amine or aldehyde groups needed for crosslinking reactions. Here, following the developed protocol with slight modifications, we have successfully crosslinked Gel B in different conditions, obtaining eight out of nine compounds in high yield (57-99%). The determined crosslinking degree percentage (CP%) evidenced a high CP% for compounds obtained in presence of LO and using the styrenic amine-containing (CP5/DMAA) and acrylic aldehyde-containing (CPMA/DMAA) copolymers as crosslinking agents. ATR-FTIR analyses confirmed the chemical structure of all compounds, while optical microscopy demonstrated cavernous, crater-like, and labyrinth-like morphologies and cavities with a size in the range 15-261 µm. An apparent density in the range 0.10-0.45 g/cm3 confirmed the aerogel-like structure of most samples. Although the best biodegradation profile was observed for the sample obtained using 10% CP5/DMAA (M3), high swelling and absorption properties, high porosity, and good biodegradation profiles were also observed for samples obtained using the 5-10% CP5/DMAA (M4, 5, 6) and 20% CPMA/DMAA (M9) copolymers. Collectively, in this work of synthesis and physicochemical characterization, new aerogel-like composites have been developed and, based on their characteristics, which fit well within the requirements for TE, five candidates (M3, M4, M5, M6, and M9) suitable for future biological experiments on cell adhesion, infiltration and proliferation, to confirm their effective functioning, have been identified.


Asunto(s)
Materiales Biocompatibles , Gelatina , Hidrogeles , Medicina Regenerativa , Andamios del Tejido , Gelatina/química , Andamios del Tejido/química , Medicina Regenerativa/métodos , Materiales Biocompatibles/química , Hidrogeles/química , Hidrogeles/síntesis química , Humanos , Ingeniería de Tejidos/métodos , Reactivos de Enlaces Cruzados/química
2.
New Phytol ; 237(5): 1495-1504, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36511294

RESUMEN

Nonvascular photoautotrophs (NVP), including bryophytes, lichens, terrestrial algae, and cyanobacteria, are increasingly recognized as being essential to ecosystem functioning in many regions of the world. Current research suggests that climate change may pose a substantial threat to NVP, but the extent to which this will affect the associated ecosystem functions and services is highly uncertain. Here, we propose a research agenda to address this urgent question, focusing on physiological and ecological processes that link NVP to ecosystem functions while also taking into account the substantial taxonomic diversity across multiple ecosystem types. Accordingly, we developed a new categorization scheme, based on microclimatic gradients, which simplifies the high physiological and morphological diversity of NVP and world-wide distribution with respect to several broad habitat types. We found that habitat-specific ecosystem functions of NVP will likely be substantially affected by climate change, and more quantitative process understanding is required on: (1) potential for acclimation; (2) response to elevated CO2 ; (3) role of the microbiome; and (4) feedback to (micro)climate. We suggest an integrative approach of innovative, multimethod laboratory and field experiments and ecophysiological modelling, for which sustained scientific collaboration on NVP research will be essential.


Asunto(s)
Briófitas , Líquenes , Ecosistema , Cambio Climático , Plantas , Briófitas/fisiología , Líquenes/fisiología
3.
Bioscience ; 73(6): 441-452, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37397836

RESUMEN

Stormwater is a vital resource and dynamic driver of terrestrial ecosystem processes. However, processes controlling interactions during and shortly after storms are often poorly seen and poorly sensed when direct observations are substituted with technological ones. We discuss how human observations complement technological ones and the benefits of scientists spending more time in the storm. Human observation can reveal ephemeral storm-related phenomena such as biogeochemical hot moments, organismal responses, and sedimentary processes that can then be explored in greater resolution using sensors and virtual experiments. Storm-related phenomena trigger lasting, oversized impacts on hydrologic and biogeochemical processes, organismal traits or functions, and ecosystem services at all scales. We provide examples of phenomena in forests, across disciplines and scales, that have been overlooked in past research to inspire mindful, holistic observation of ecosystems during storms. We conclude that technological observations alone are insufficient to trace the process complexity and unpredictability of fleeting biogeochemical or ecological events without the shower thoughts produced by scientists' human sensory and cognitive systems during storms.

4.
Wilderness Environ Med ; 31(3): 266-272, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32682706

RESUMEN

INTRODUCTION: The potential efficacy of selected plant extracts to counteract the dermal toxicity of jellyfish envenomation was investigated using an in vitro cell culture model. METHODS: We studied plant extracts from Carica papaya, Ananas comosus, and Bouvardia ternifolia, known for their antivenom properties, in pairwise combinations with tissue homogenates of the jellyfish Pelagia noctiluca, Phyllorhiza punctata, and Cassiopea andromeda, to evaluate modulations of jellyfish cytotoxic effects. L929 mouse fibroblasts were incubated with pairwise jellyfish/plant extract combinations and examined by MTT assay (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide). RESULTS: C papaya and A comosus significantly lowered the cytotoxicity of P noctiluca and P punctata but induced a slight worsening of C andromeda cytotoxicity. Conversely, B ternifolia was protective against P punctata, ineffective against P noctiluca, and worsened C andromeda cytotoxicity. CONCLUSIONS: Data showed species-specific and contrasting effects of plant extracts, suggesting that those containing protease activities, namely A comosus and C papaya, are more effective in lowering the cytotoxicity of jellyfish venom containing toxic peptidic factors such as phospholipase A. However, all examined plants require further investigation in vivo to evaluate their ability to counteract jellyfish injury to the skin.


Asunto(s)
Antivenenos/farmacología , Venenos de Cnidarios/efectos adversos , Extractos Vegetales/farmacología , Escifozoos/efectos de los fármacos , Ananas/química , Animales , Antivenenos/química , Carica/química , Ratones , Extractos Vegetales/química , Rubiaceae/química , Sales de Tetrazolio , Tiazoles
5.
Oncologist ; 24(3): 385-393, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30606884

RESUMEN

BACKGROUND: Type 2 diabetes mellitus (T2DM) is associated with increased risk of colon cancer (CC), whereas metformin use seems to be protective. However, the impact of metformin use on the risk of death or disease recurrence after radical surgery for CC remains uncertain. MATERIALS AND METHODS: This is a substudy conducted in patients with high-risk stage II or stage III CC randomized in the TOSCA trial, which compared 3 versus 6 months of fluoropyrimidine-oxaliplatin adjuvant chemotherapy. Objective of the study was to investigate the impact of metformin exposure during adjuvant chemotherapy on overall survival (OS) and relapse-free survival (RFS). We also evaluated the impact of T2DM or metformin dosage on clinical outcomes. RESULTS: Out of 3,759 patients enrolled in the TOSCA trial, 133 patients with diabetes (9.2%) and 1,319 without diabetes (90.8%) were recruited in this study. After excluding 13 patients with diabetes without information on metformin exposure, 76 patients with T2DM (63.3%) were defined as metformin users and 44 (36.7%) as metformin nonusers. After a median follow-up of 60.4 months, 26 (21.7%) patients relapsed and 16 (13.3%) died. Metformin use was neither associated with OS (adjusted hazard ratio [HR], 1.51; 95% confidence interval [CI], 0.48-4.77; p = .4781) nor with RFS (HR, 1.56; 95% CI, 0.69-3.54; p = .2881). Similarly, we found no association between T2DM or metformin dosage and OS or RFS. CONCLUSIONS: Metformin use and T2DM did not impact on OS or RFS in patients with resected CC treated with adjuvant fluoropyrimidine-oxaliplatin chemotherapy. Larger studies and longer follow-up are required to clarify the potential efficacy of metformin in improving the prognosis of patients with CC. IMPLICATIONS FOR PRACTICE: The role of the antidiabetic drug metformin in colon cancer prevention and treatment is highly debated. While low-dose metformin reduced the incidence of colorectal adenomas in two prospective studies, its effect in patients with already established colon cancer remains unclear. In this study, the potential impact of metformin on the survival of resected colon cancer patients who received adjuvant chemotherapy was investigated in the context of the TOSCA study. We did not find any association between metformin use or dosages and patient survival. Prospective studies are required to draw definitive conclusions about metformin impact on colon cancer recurrence and survival.


Asunto(s)
Antineoplásicos/uso terapéutico , Quimioterapia Adyuvante/métodos , Neoplasias del Colon/tratamiento farmacológico , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Fluorouracilo/análogos & derivados , Fluorouracilo/uso terapéutico , Hipoglucemiantes/uso terapéutico , Metformina/uso terapéutico , Oxaliplatino/uso terapéutico , Anciano , Antineoplásicos/farmacología , Neoplasias del Colon/patología , Diabetes Mellitus Tipo 2/patología , Femenino , Fluorouracilo/farmacología , Humanos , Hipoglucemiantes/farmacología , Masculino , Metformina/farmacología , Persona de Mediana Edad , Oxaliplatino/farmacología , Factores de Riesgo
6.
Stat Med ; 37(1): 137-156, 2018 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-29023942

RESUMEN

In many situations, a researcher is interested in the analysis of the scores of a set of observation units on a set of variables. However, in medicine, it is very frequent that the information is replicated at different occasions. The occasions can be time-varying or refer to different conditions. In such cases, the data can be stored in a 3-way array or tensor. The Candecomp/Parafac and Tucker3 methods represent the most common methods for analyzing 3-way tensors. In this work, a review of these methods is provided, and then this class of methods is applied to a 3-way data set concerning hospital care data for a hospital in Rome (Italy) during 15 years distinguished in 3 groups of consecutive years (1892-1896, 1940-1944, 1968-1972). The analysis reveals some peculiar aspects about the use of health services and its evolution along the time.


Asunto(s)
Bioestadística/métodos , Servicios de Salud/estadística & datos numéricos , Registros de Hospitales/estadística & datos numéricos , Interpretación Estadística de Datos , Bases de Datos Factuales/estadística & datos numéricos , Humanos , Modelos Estadísticos , Análisis de Componente Principal/métodos , Ciudad de Roma , Programas Informáticos
7.
J Plant Res ; 131(4): 633-640, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29500748

RESUMEN

Pollination ecology and breeding system of Lilium pomponium L. were studied, and their effect on the reproductive outcome was assessed. This species has high conservation interest in Europe, because it is included in Annex V of the EU Habitat Directive and it is one out of the five Lilium species listed in IUCN Global Red List. To achieve our aim, the pollen vectors as well as the effect of bagging, emasculation and artificial pollination on reproductive output were studied. The most frequent visitor was the Lepidopteran Gonepteryx rhamnii. In general, reproductive outputs were close to zero for all the self-pollination treatments; however, geitonogamy and facilitated selfing seem slightly more efficient than autogamy, as also confirmed by self-compatibility and autofertility indices. Altogether, our results suggest a self-incompatible outcrossing breeding system, with a poor capacity for selfing. Nevertheless, climate change and anthropic threats might promote a shift toward self-fertilization, even maladaptive, favouring the few individuals able to produce selfed seeds.


Asunto(s)
Lilium/fisiología , Animales , Mariposas Diurnas , Ecología , Especies en Peligro de Extinción , Francia , Insectos , Italia , Polinización/fisiología , Reproducción/fisiología , Autoincompatibilidad en las Plantas con Flores/fisiología
8.
Environ Res ; 154: 291-295, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-28126689

RESUMEN

Tree bark has proved to be a useful bioindicator for trace elements in the atmosphere, however it reflects an exposure occurring during an unidentified period of time, so it provides spatial information about the distribution of contaminants in a certain area, but it cannot be used to detect temporal changes or trends, which is an important achievement in environmental studies. In order to obtain information about a known period of time, the bark collected from the annual segments of tree branches can be used, allowing analyses going back 10-15 years with annual resolution. In the present study, the concentrations of As, Cd, Co, Cu, Fe, Mn, Ni, Pb, V and Zn were measured by atomic emission spectrometry in a series of samples covering the period from 2001 to 2013 in an urban environment. Downward time trends were significant for Cd, Pb and Zn. The only trace element showing an upward time trend was V. The concentrations of the remaining six trace elements were constant over time, showing that their presence in bark is not simply proportional to the duration of exposure. This approach, which is simple, reliable and widely applicable at a low cost, allows the "a posteriori" reconstruction of atmospheric trace element deposition when or where no monitoring programme is in progress and no other natural archives are available.


Asunto(s)
Contaminantes Atmosféricos/análisis , Atmósfera/química , Monitoreo del Ambiente/métodos , Metales Pesados/análisis , Corteza de la Planta/química , Quercus/química , Oligoelementos/análisis , Atmósfera/análisis , Ciudades , Italia , Estudios Retrospectivos
9.
Gastric Cancer ; 16(3): 411-9, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23065042

RESUMEN

BACKGROUND: Elderly patients are generally underrepresented in the study populations of combination chemotherapy trials. This study evaluates the efficacy and safety of a modified FOLFOX regimen in elderly patients with metastatic gastric cancer and presenting associated disease(s). METHODS: A total of 43 patients aged ≥70 years received oxaliplatin 85 mg/m(2) together with 6S-leucovorin 200 mg/m(2) on day 1, followed by a 46-h infusion of 5-fluorouracil 2,400 mg/m(2), every 2 weeks. Assessment of response was performed every four cycles according to RECIST criteria. RESULTS: Median patient age was 74 years (range, 70-83 years). Overall response rate was 34.9% [95% confidence interval (CI), 20.6-49.1, with 3 complete responses and 12 partial responses. Grade 3 neutropenia occurred in 4 patients (9.3%), fatigue in 3 patients (7.0%), and vomiting in 2 patients (4.6%). Grade 2 and 3 peripheral neuropathy was observed in 5 patients (11.6%) and 1 patient (2.3%), respectively. No treatment-related death was observed. Median progression-free and overall survival were 6.8 and 10.5 months, respectively. CONCLUSIONS: This modified FOLFOX regimen is an active and well-tolerated treatment for elderly patients with metastatic gastric cancer and also represents a good therapeutic option in patients with associated disease(s).


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias Gástricas/tratamiento farmacológico , Factores de Edad , Anciano , Anciano de 80 o más Años , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Supervivencia sin Enfermedad , Femenino , Fluorouracilo/efectos adversos , Fluorouracilo/uso terapéutico , Humanos , Leucovorina/efectos adversos , Leucovorina/uso terapéutico , Masculino , Metástasis de la Neoplasia , Compuestos Organoplatinos/efectos adversos , Compuestos Organoplatinos/uso terapéutico , Neoplasias Gástricas/patología , Tasa de Supervivencia , Resultado del Tratamiento
10.
J Gambl Stud ; 29(4): 765-74, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22926579

RESUMEN

The aim of this study was to adapt to the Italian context a very commonly used international instrument to detect problem gambling, the canadian problem gambling index (CPGI), and assess its psychometric properties. Cross-cultural adaptation of CPGI was performed in several steps and the questionnaire was administered as a survey among Italian general population (n = 5,292). Cronbach's alpha reliability coefficient was 0.87 and can be considered to be highly reliable. Construct validity was assessed first by means of a principal component analysis and then by means of confirmatory factor analysis, showing that only one factor, problem gambling, was extracted from the CPGI questionnaire (an eigenvalues of 4,684 with percentage of variance 52 %). As far as convergent validity is concerned, CPGI was compared with Lie/Bet questionnaire, a two-item screening tool for detecting problem gamblers, and with both depression and stress scales. A short form DSM-IV CIDI questionnaire was used for depression and VRS scale, a rating scale, was used for rapid stress evaluation. A strong convergent validity with these instruments was found and these findings are consistent with past research on problem gambling, where another way to confirm the validity is to determine the extent to which it correlates with other qualities or measures known to be directly related to problem gambling. In sum, despite the lack of a direct comparison with a classic gold-standard such as DSM-IV, the Italian version of CPGI exhibits good psychometric properties and can be used among the Italian general population to identify at-risk problem gamblers.


Asunto(s)
Conducta Adictiva/diagnóstico , Juego de Azar/psicología , Encuestas y Cuestionarios , Adulto , Femenino , Humanos , Italia , Masculino , Psicometría , Reproducibilidad de los Resultados
11.
Environ Monit Assess ; 185(2): 1567-76, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22628101

RESUMEN

The variability of biological data is a main constraint affecting the quality and reliability of lichen biomonitoring surveys for estimation of the effects of atmospheric pollution. Although most epiphytic lichen bioindication surveys focus on between-site differences at the landscape level, associated with the large scale effects of atmospheric pollution, current protocols are based on multilevel sampling, thus adding further sources of variation and affecting the error budget. We test the hypothesis that assemblages of lichen communities vary at each spatial scale examined, in order to determine what scales should be included in future monitoring studies. We compared four sites in Italy, along gradients of atmospheric pollution and climate, to test the partitioning of the variance components of lichen diversity across spatial scales (from trunks to landscapes). Despite environmental heterogeneity, we observed comparable spatial variance. However, residuals often overcame between-plot variability, leading to biased estimation of atmospheric pollution effects.


Asunto(s)
Contaminantes Atmosféricos/análisis , Contaminación del Aire/estadística & datos numéricos , Biodiversidad , Monitoreo del Ambiente/métodos , Líquenes/química , Contaminantes Atmosféricos/toxicidad , Clima , Italia , Líquenes/clasificación , Análisis Espacial
12.
Plants (Basel) ; 12(9)2023 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-37176967

RESUMEN

This study compares the knowledge of medicinal plants of Bissau-Guinean migrants now established in Italy with the ethnopharmacology still present in their country of origin. We also investigated how traditional ethnobotanical knowledge is changing following the phenomenon of migration from Africa to Europe. The ethnobotanical data were collected during 2017-2018, by interviewing 49 informants belonging to 8 ethnic groups, living in 8 provinces of northern Italy. The final inventory of botanical taxa included 81 species belonging to 34 families, with Fabaceae and Malvaceae the most represented, followed by Euphorbiaceae, Apocynaceae, Combretaceae, and Solanaceae. Plant remedies were used to treat 21 ailment categories, such as fever, internal infections, intestinal and respiratory problems, and pains. The traditional ethnobotanical knowledge of Bissau-Guinean migrants in Italy was associated with gender, with women showing the highest knowledge. In addition, a negative relationship was observed between the maintenance of this knowledge and the number of years migrants have spent in Italy. Overall, a loss of knowledge was observed in the less numerous ethnic groups. However, traditional preparations based on plants from the country of origin are in general well preserved to maintain a good state of health. Our work could help in transferring to the next generation the cultural heritage of Bissau-Guinean people permanently moved to European Countries.

13.
J Fungi (Basel) ; 9(11)2023 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-37998870

RESUMEN

In the 1990s, a sampling network for the biomonitoring of forests using epiphytic lichen diversity was established in the eastern Iberian Peninsula. This area registered air pollution impacts by winds from the Andorra thermal power plant, as well as from photo-oxidants and nitrogen depositions from local and long-distance transport. In 1997, an assessment of the state of lichen communities was carried out by calculating the Index of Atmospheric Purity. In addition, visible symptoms of morphological injury were recorded in nine macrolichens pre-selected by the speed of symptom evolution and their wide distribution in the territory. The thermal power plant has been closed and inactive since 2020. During 2022, almost 25 years later, seven stations of this previously established biomonitoring were revaluated. To compare the results obtained in 1997 and 2022, the same methodology was used, and data from air quality stations were included. We tested if, by integrating innovative methodologies (NIRS) into biomonitoring tools, it is possible to render an integrated response. The results displayed a general decrease in biodiversity in several of the sampling plots and a generalised increase in damage symptoms in the target lichen species studied in 1997, which seem to be the consequence of a multifactorial response.

14.
Gastric Cancer ; 15(4): 419-26, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22237659

RESUMEN

BACKGROUND: The combination of docetaxel, cisplatin, and 5-fluorouracil (5-FU) has demonstrated a survival advantage over cisplatin and 5-FU, but with substantial hematological toxicity. We aimed to evaluate the efficacy and toxicity of a sequential regimen with cisplatin, leucovorin, and 5-FU (PLF) followed by docetaxel in metastatic gastric cancer patients. METHODS: Treatment consisted of 4 cycles of biweekly PLF (cisplatin 50 mg/m(2) as a 30-min infusion on day 1, leucovorin 200 mg/m(2) in a 2-h infusion, and 5-FU 2,800 mg/m(2) in a 48-h continuous infusion starting on day 1) followed, in cases of response or stable disease, by 3 cycles of docetaxel (75 mg/m(2), every 3 weeks). RESULTS: Thirty-four patients were enrolled, with an average age of 64 years (range 34-69). The main cumulative grade 3-4 toxicities were: neutropenia (38.2%), febrile neutropenia (11.8%), and fatigue (14.7%). After the planned 7 cycles of treatment, the overall response rate was 38.2% (95% confidence interval [CI] 21.9-54.6), with 3 complete and 10 partial responses. Median progression-free survival and overall survival were 4.8 and 10.6 months, respectively. CONCLUSIONS: For patients with metastatic gastric cancer, the sequential administration of cisplatin, leucovorin, 5-FU, and docetaxel may be an effective palliative option and offers a far more favorable toxicity profile than the simultaneous use of docetaxel, cisplatin, and 5-FU.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias Gástricas/tratamiento farmacológico , Neoplasias Gástricas/mortalidad , Adulto , Anciano , Cisplatino/administración & dosificación , Supervivencia sin Enfermedad , Docetaxel , Esquema de Medicación , Femenino , Fluorouracilo/administración & dosificación , Humanos , Leucovorina/administración & dosificación , Masculino , Persona de Mediana Edad , Neoplasias Gástricas/patología , Análisis de Supervivencia , Taxoides/administración & dosificación , Resultado del Tratamiento
16.
Sci Total Environ ; 825: 153943, 2022 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-35189219

RESUMEN

Climate change is already causing considerable reductions in biodiversity in all terrestrial ecosystems. These consequences are expected to be exacerbated in biomes that are particularly exposed to change, such as those in the Mediterranean, and in certain groups of more sensitive organisms, such as epiphytic lichens. These poikylohydric organisms find suitable light and water conditions on trunks under the tree canopy. Despite their small size, epiphytic communities contribute significantly to the functionality of forest ecosystems. In this work, we surveyed epiphytic lichen communities in a Mediterranean area (Sardinia, Italy) and hypothesized that 1) the effect of microclimate on lichens at tree scale is mediated by the functional traits of these organisms and that 2) micro-refuge trees with certain morphological characteristics can mitigate the negative effects of future climate change. Results confirm the first hypothesis, while the second is only partially supported, suggesting that the capability of specific trees to host specific conditions may not be sufficient to maintain the diversity and ecosystem functionality of lichen communities in the Mediterranean.


Asunto(s)
Líquenes , Biodiversidad , Cambio Climático , Ecosistema , Bosques , Árboles
17.
Plants (Basel) ; 11(3)2022 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-35161276

RESUMEN

Microclimatic conditions are important in determining lichen distribution at small scale, and may determine whether the species persist when the surrounding environmental conditions have drastically changed. This is the case with forest management, since a sudden variation of microclimatic conditions (increase of solar radiation, temperature, wind and a reduction of humidity) may occur after logging. In this study, the combined effect of forest logging and microclimatic conditions on the growth probabilities and growth rates of the model species Lobaria pulmonaria was assessed in mixed oak stands. To this purpose, 800 fragments of L. pulmonaria (<1 cm) were transplanted in logged and unlogged stands for two years. Young and adult fragments were positioned on Turkey oak boles according to distance from the ground (100 and 50 cm) and aspect (north and south). The results, evaluated by generalized linear mixed models on a yearly basis, highlighted differences in growth-particularly on isolated trees in the logged stand. South-exposed samples in the logged stand showed a low probability of growth, while samples transplanted north in the unlogged stand showed higher growth probabilities. However, the highest annual growth coefficients corresponded to south-exposed samples 50 cm from the ground in the unlogged stand. In general, higher growth rates were observed in young thallus fragments when compared with adult ones. Beyond confirming the importance of microclimate for lichen ecology, these results could be implemented in conservation actions to preserve L. pulmonaria populations in logged forests.

18.
Environ Pollut ; 315: 120330, 2022 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-36274289

RESUMEN

To create more resilient cities, it is important that we understand the effects of the global change drivers in cities. Biodiversity-based ecological indicators (EIs) can be used for this, as biodiversity is the basis of ecosystem structure, composition, and function. In previous studies, lichens have been used as EIs to monitor the effects of global change drivers in an urban context, but only in single-city studies. Thus, we currently do not understand how lichens are affected by drivers that work on a broader scale. Therefore, our aim was to quantify the variance in lichen biodiversity-based metrics (taxonomic and trait-based) that can be explained by environmental drivers working on a broad spatial scale, in an urban context where local drivers are superimposed. To this end, we performed an unprecedented effort to sample epiphytic lichens in 219 green spaces across a continental gradient from Portugal to Estonia. Twenty-six broad-scale drivers were retrieved, including air pollution and bio-climatic variables, and their dimensionality reduced by means of a principal component analysis (PCA). Thirty-eight lichen metrics were then modelled against the scores of the first two axes of each PCA, and their variance partitioned into pollution and climate components. For the first time, we determined that 15% of the metric variance was explained by broad-scale drivers, with broad-scale air pollution showing more importance than climate across the majority of metrics. Taxonomic metrics were better explained by air pollution, as expected, while climate did not surpass air pollution in any of the trait-based metric groups. Consequently, 85% of the metric variance was shown to occur at the local scale. This suggests that further work is necessary to decipher the effects of climate change. Furthermore, although drivers working within cities are prevailing, both spatial scales must be considered simultaneously if we are to use lichens as EIs in cities at continental to global scales.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Líquenes , Líquenes/fisiología , Ecosistema , Monitoreo del Ambiente , Contaminación del Aire/análisis , Biodiversidad , Contaminantes Atmosféricos/análisis
19.
Histopathology ; 58(5): 669-78, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21447133

RESUMEN

AIMS: HtrA1 is a member of the HtrA (high-temperature requirement factor A) family of serine proteases. HtrA1 plays a protective role in various malignancies due to its tumour suppressive properties. The aim of this study was to determine HtrA1 expression as a predictor of chemoresponse in patients with advanced gastric cancer. METHODS AND RESULTS: HtrA1 expression was determined by immunohistochemistry on specimens of primary gastric cancer from 80 patients treated consecutively with cisplatin-based combination chemotherapy. Response to chemotherapy was assessed according to Response Evaluation Criteria in Solid Tumours (RECIST) criteria. Our population consisted of males/females [51/29; median age 64 years (range 32-82)]. A complete or partial response was observed in 71.4% [95% confidence interval (CI) 54.7-88.2], 66.7% (95% CI 47.8-85.5) and 28.6% (95 CI 11.8-45.3) of tumours showing high, medium and low HtrA1 expression, respectively. A statistically significant association between HtrA1 expression and the clinical response was observed (P = 0.002). The median overall survival for patients with high/medium expression was 17 months compared to 9.5 months for patients with low HtrA1 expression (P = 0.037). CONCLUSIONS: Identification of HtrA1 in gastric cancer prior to chemotherapy indicates that levels of HtrA1 could be used to predict response to platinum-based combination therapies. Further assessment of HtrA1 expression is highly warranted in large, prospective studies.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Cisplatino/administración & dosificación , Serina Endopeptidasas/metabolismo , Neoplasias Gástricas/tratamiento farmacológico , Adulto , Anciano , Anciano de 80 o más Años , Cisplatino/uso terapéutico , Femenino , Serina Peptidasa A1 que Requiere Temperaturas Altas , Humanos , Masculino , Persona de Mediana Edad , Neoplasias Gástricas/enzimología , Neoplasias Gástricas/mortalidad , Análisis de Supervivencia
20.
Br J Math Stat Psychol ; 74(3): 541-566, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-33629738

RESUMEN

Principal covariate regression (PCOVR) is a method for regressing a set of criterion variables with respect to a set of predictor variables when the latter are many in number and/or collinear. This is done by extracting a limited number of components that simultaneously synthesize the predictor variables and predict the criterion ones. So far, no procedure has been offered for estimating statistical uncertainties of the obtained PCOVR parameter estimates. The present paper shows how this goal can be achieved, conditionally on the model specification, by means of the bootstrap approach. Four strategies for estimating bootstrap confidence intervals are derived and their statistical behaviour in terms of coverage is assessed by means of a simulation experiment. Such strategies are distinguished by the use of the varimax and quartimin procedures and by the use of Procrustes rotations of bootstrap solutions towards the sample solution. In general, the four strategies showed appropriate statistical behaviour, with coverage tending to the desired level for increasing sample sizes. The main exception involved strategies based on the quartimin procedure in cases characterized by complex underlying structures of the components. The appropriateness of the statistical behaviour was higher when the proper number of components were extracted.


Asunto(s)
Proyectos de Investigación , Simulación por Computador , Intervalos de Confianza , Tamaño de la Muestra
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