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1.
Oecologia ; 201(2): 421-434, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36738314

RESUMO

Species distribution models are the most widely used tool to predict species distributions for species conservation and assessment of climate change impact. However, they usually do not consider intraspecific ecological variation exhibited by many species. Overlooking the potential differentiation among groups of populations may lead to misplacing any conservation actions. This issue may be particularly relevant in species in which few populations with potential local adaptation occur, as in species with disjunct populations. Here, we used ecological niche modeling to analyze how the projections of current and future climatically suitable areas of 12 plant species can be affected using the whole taxa occurrences compared to occurrences from geographically disjunct populations. Niche analyses suggest that usually the disjunct group of populations selects the climatic conditions as similar as possible to the other according to climate availability. Integrating intraspecific variability only slightly increases models' ability to predict species occurrences. However, it results in different predictions of the magnitude of range change. In some species, integrating or not integrating intraspecific variability may lead to opposite trend in projected range change. Our results suggest that integrating intraspecific variability does not strongly improve overall models' accuracy, but it can result in considerably different conclusions about future range change. Consequently, accounting for intraspecific differentiation may enable the detection of potential local adaptations to new climate and so to design targeted conservation strategies.


Assuntos
Mudança Climática , Ecossistema , Adaptação Fisiológica , Aclimatação , Plantas
2.
Ann Bot ; 129(6): 697-708, 2022 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-35325927

RESUMO

BACKGROUND AND AIMS: Self-fertilization is often associated with ecological traits corresponding to the ruderal strategy, and selfers are expected to be less competitive than outcrossers, either because of a colonization/competition trade-off or because of the deleterious genetic effects of selfing. Range expansion could reduce further competitive ability while polyploidy could mitigate the effects of selfing. If pollinators are not limited, individual fitness is thus expected to be higher in outcrossers than in selfers and, within selfers, in polyploids than in diploids. Although often proposed in the botanical literature and also suggested by meta-analyses, these predictions have not been directly tested yet. METHODS: In order to compare fitness and the competitive ability of four Capsella species with a different mating system and ploidy level, we combined two complementary experiments. First, we carried out an experiment outdoors in north-west Greece, i.e. within the range of the obligate outcrossing species, C. grandiflora, where several life history traits were measured under two different disturbance treatments, weeded plots vs. unweeded plots. To better control competition and to remove potential effects of local adaptation of the outcrosser, we also performed a similar competition experiment but under growth chamber conditions. KEY RESULTS: In the outdoor experiment, disturbance of the environment did not affect the phenotype in any of the four species. For most traits, the obligate outcrossing species performed better than all selfing species. In contrast, polyploids did not survive or reproduce better than diploids. Under controlled conditions, as in the field experiment, the outcrosser had a higher fitness than selfing species and was less affected by competition. Finally, contrary to the outdoor experiment where the two behaved identically, polyploid selfers were less affected by competition than diploid selfes. CONCLUSIONS: In the Capsella genus, selfing induces lower fitness than outcrossing and can also reduce competitive ability. The effect of polyploidy is, however, unclear. These results highlight the possible roles of ecological context in the evolution of selfing species.


Assuntos
Capsella , Capsella/genética , Ploidias , Poliploidia , Reprodução/genética , Autofertilização
3.
PLoS Genet ; 15(2): e1007949, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30768594

RESUMO

Allopolyploidy is generally perceived as a major source of evolutionary novelties and as an instantaneous way to create isolation barriers. However, we do not have a clear understanding of how two subgenomes evolve and interact once they have fused in an allopolyploid species nor how isolated they are from their relatives. Here, we address these questions by analyzing genomic and transcriptomic data of allotetraploid Capsella bursa-pastoris in three differentiated populations, Asia, Europe, and the Middle East. We phased the two subgenomes, one descended from the outcrossing and highly diverse Capsella grandiflora (CbpCg) and the other one from the selfing and genetically depauperate Capsella orientalis (CbpCo). For each subgenome, we assessed its relationship with the diploid relatives, temporal changes of effective population size (Ne), signatures of positive and negative selection, and gene expression patterns. In all three regions, Ne of the two subgenomes decreased gradually over time and the CbpCo subgenome accumulated more deleterious changes than CbpCg. There were signs of widespread admixture between C. bursa-pastoris and its diploid relatives. The two subgenomes were impacted differentially depending on geographic region suggesting either strong interploidy gene flow or multiple origins of C. bursa-pastoris. Selective sweeps were more common on the CbpCg subgenome in Europe and the Middle East, and on the CbpCo subgenome in Asia. In contrast, differences in expression were limited with the CbpCg subgenome slightly more expressed than CbpCo in Europe and the Middle-East. In summary, after more than 100,000 generations of co-existence, the two subgenomes of C. bursa-pastoris still retained a strong signature of parental legacy but their evolutionary trajectory strongly varied across geographic regions.


Assuntos
Capsella/genética , Evolução Molecular , Genoma de Planta , Tetraploidia , Ásia , Capsella/classificação , DNA de Plantas/genética , Diploide , Europa (Continente) , Genética Populacional , Hibridização Genética , Oriente Médio , Modelos Genéticos , Mutação , Filogenia , Filogeografia , Poliploidia , Especificidade da Espécie
4.
Oecologia ; 195(1): 93-103, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33269409

RESUMO

Geographical limits of species' distributions are assumed to be coincident with ecological margins, although this assumption might not always be true. Indeed, harsh environments such as Alpine and Mediterranean ecosystems may favour high phenotypic variability among populations, especially those in peripheral sites. Floral traits are often found to be less variable and less affected by environmental heterogeneity than vegetative traits because variation in the former may have negative effects on fitness. For this reason, it is important to quantify variation in floral traits and plant fecundity in study range limits. The objective of the study is to examine phenotypic variation and differences in reproduction in endemic Lilium pomponium in the Maritime and Ligurian Alps in relation to environmental variation across its distribution range. In this species, marginal climatic populations occur both in the peripheral and central geographical locations of the distribution range; hence, geographical and ecological gradients are not concordant. Floral trait variation is related to local environmental conditions with an array of interactions among resource availability, potential pollen limitation and population size that are differentially related to floral traits. Contrary to the general expectation, all central and peripheral populations had similar, moderate seed production with each group limited by different factors acting on different stages of the life-history strategy. Our results are in line with the idea that general expectations are confirmed only when its assumptions are met and that the differences in pollination environment along an environmental gradient may not be the main determinant of the distribution limit.


Assuntos
Lilium , Variação Biológica da População , Ecossistema , Plantas , Polinização
5.
J Plant Res ; 131(4): 633-640, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29500748

RESUMO

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.


Assuntos
Lilium/fisiologia , Animais , Borboletas , Ecologia , Espécies em Perigo de Extinção , França , Insetos , Itália , Polinização/fisiologia , Reprodução/fisiologia , Autoincompatibilidade em Angiospermas/fisiologia
6.
J Plant Res ; 129(3): 477-85, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26886434

RESUMO

Climate change is known to have a profound influence on plant reproduction, mainly because it affects plant/pollinator interactions, sometimes driving plants to extinction. Starting from the Neogene, the European climate was subjected to severe alterations. Nevertheless, several genera, including Berardia, survived these climatic changes. Despite the numerous studies performed about the relationship between climate change and plant reproductive biology, equivalent studies on ancient species are lacking, even though they may furnish crucial information on the strategies that allowed them to survive drastic climatic fluctuations. We investigated floral and reproductive features in Berardia subacaulis (Asteraceae), describing pollen vectors, capitulum and florets phenology, evaluating reproductive efficiency and defining the reproductive mode of the plant with bagging experiments and test of apomixis. B. subacaulis grows in habitats with low pollination services; it is self-compatible, but many typical features favouring cross-pollination are still present: florets are characterized by incomplete protandry, capitulum protogyny and high pollen-ovule ratio. The plant is not apomictic and self-fertilization is allowed within each capitulum. Similarly to other European Alpine endemics supposed to belong to the Mediterranean ancient tropical flora, the reproductive mode observed in the monospecific genus Berardia assured reproduction also under a pollinator decline. Differently from the other endemics, it took advantage of its spontaneous self-pollination and compatibility and its generalist pollination service, common both among high altitude plants and in the Asteraceae.


Assuntos
Asteraceae/fisiologia , Mudança Climática , Ecossistema , Animais , Frutas/crescimento & desenvolvimento , Insetos , Pólen/fisiologia , Reprodução
7.
J Plant Res ; 127(1): 141-50, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-23963860

RESUMO

Reduction of pollen flow can affect plant abundance and population viability and cause selection on plant mating system and floral traits. Little is known on the effect of this phenomenon in species naturally restricted to small and isolated habitats, that may have developed strategies to cope with long-term isolation and small population size. We investigated the pollination ecology of the endemic distylous winter-flowering P. allionii to verify the possible limitation of female fitness due to reduced pollinator visits. We recorded a higher production of pollen grains in long-styled morph, and a higher seed set in short-styled morph. The high intra-morph variability of sexual organ position may explain the hybridization phenomena allowing and easier intra-morph pollination. The fruit set is constant, although its winter-flowering period might decrease pollen transfer. Nevertheless, the lower competition for pollinators with neighbouring plants and the long-lasting anthesis may offset its reproductive success. Even if our results show no evidence of imminent threats, changes in plant-pollinator interactions might increase inbreeding, resulting in an increased extinction risk.


Assuntos
Abelhas/fisiologia , Dípteros/fisiologia , Primula/fisiologia , Animais , Abelhas/anatomia & histologia , Dípteros/anatomia & histologia , Ecossistema , Flores/anatomia & histologia , Flores/fisiologia , Fenótipo , Pólen/anatomia & histologia , Pólen/fisiologia , Polinização , Primula/anatomia & histologia , Reprodução , Estações do Ano , Sementes/anatomia & histologia , Sementes/fisiologia , Fatores de Tempo
8.
Ecancermedicalscience ; 18: 1697, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38774562

RESUMO

Introduction: Adjuvant treatment with aromatase inhibitors (AI) in oestrogen receptor-positive and/or progesterone receptor-positive breast cancer (BC) has been shown to increase overall survival. However, arthralgias and myalgias are common adverse effects in patients treated with AI. Objective: To evaluate the frequency and characteristics of arthralgias and myalgias in patients with early BC-treated adjuvantly with AI in the Mastology Unit of the Oncology Service of the Hospital de Clínicas and the Departmental Hospital of Soriano. Materials and methods: A prospective, cross-sectional and descriptive study was performed. A questionnaire was administered to patients to assess the presence and characteristics of arthralgias and myalgias associated with AI. Statistical analysis: 'Age' was described with measures of central tendency and dispersion. Qualitative variables were presented in absolute and relative frequencies. Logistic models were used to evaluate the association between patient characteristics, tumour characteristics, treatment characteristics and the presence of pain. Results were presented by odds ratio and p-value, using R software (version 4.1.2) with a significance threshold of 5%. Results: 83 patients were included, with a median age of 69 years. 75.9% presented arthralgias and/or myalgias related to treatment, with an average intensity of 5-7. 80.9% received non-steroidal anti-inflammatory drugs (NSAIDs), achieving satisfactory analgesia. The presence of arthralgias and myalgias was significantly associated with age and time since the last menstrual period (LMP), being more frequent in patients older than 50 years and those with more than 5 years since the LMP. Conclusion: Approximately 70% of the patients presented arthralgias or myalgias. These findings suggest a possible role of oestrogen withdrawal in its mechanism of development. Multidisciplinary and translational research is crucial to evaluate the ethology and therapeutic options for patients with AI-related arthralgia.

9.
J Cancer Res Ther ; 20(3): 832-839, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-39023591

RESUMO

INTRODUCTION: Breast cancer (BC) and its treatment can impair patient quality of life (QoL), and those undergoing more aggressive treatments may be more severely impacted. Objective: Assess the level of perception of the QoL of patients treated for BC at the Hospital de Clínicas and the Departmental Hospital of Soriano. MATERIALS AND METHODS: A questionnaire for cancer patients (EORTC, QLQ-C30) and one specific for BC (EORTC QLQ-BR23) were used. RESULTS: A total of 158 patients who had completed chemotherapy treatment at least one year prior to the evaluation were enrolled. The average age was 61 years old. QLQC QUESTIONNAIRE: The global QoL score (GQOL) was high: 70.9. Patients undergoing breast-conservation surgery (BCS) had better scores in physical and emotional functioning (p < 0.005) and presented less frequently with: pain, constipation, and financial difficulties (p < 0.005). Those undergoing sentinel lymph node biopsy (SLNB) had higher scores for GQOL and for physical, role, and social functioning scales (p < 0.001) and had less fatigue, pain, insomnia, and financial difficulties (p < 0.005). QUESTIONNAIRE QLQBR: Sexual functioning and sexual enjoyment scales were relatively low. Patients undergoing BCS had better scores on the functional scales: body image and future outlook; and fewer breast symptoms (p < 0.005). Those undergoing SLNB also had better scores on the functional scales for body image and future outlook future and presented less frequently with symptoms (p < 0.005). CONCLUSION: Uruguayan BC patients experience high values on the GQOL scale; those undergoing BCS and SLNB had better scores on most functional and problem/symptom scales. Patients undergoing BCS had better scores in physical and emotional functioning and presented less frequently with pain, constipation, and financial difficulties. With respect to the type of axillary surgery received, patients who underwent SLNB had higher scores on the GQOL scale and on the physical, role, and social functional scales. The implementation of intervention strategies aimed at improving the quality of life, and the physical and emotional care of patients is recommended.


Assuntos
Neoplasias da Mama , Qualidade de Vida , Humanos , Feminino , Neoplasias da Mama/cirurgia , Neoplasias da Mama/terapia , Neoplasias da Mama/psicologia , Neoplasias da Mama/patologia , Pessoa de Meia-Idade , Inquéritos e Questionários , Idoso , Uruguai/epidemiologia , Radioterapia Adjuvante/métodos , Radioterapia Adjuvante/estatística & dados numéricos , Adulto , Quimioterapia Adjuvante/métodos , Biópsia de Linfonodo Sentinela , Mastectomia , Mastectomia Segmentar/psicologia , Terapia Combinada
10.
Comp Cytogenet ; 18: 175-182, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39360033

RESUMO

Within a practical course of cytotaxonomy organized in Pisa (Italy) on February 2024 by the Group for Floristics, Systematics and Evolution of the Italian Botanical Society, we tested whether using image analysis softwares possible biases are still introduced by different observers. We conclude that observer bias selectively applies in possibly overestimating the length of short arms in a karyotype. As a consequence, the parameters most sensitive to these possible errors are CVCI and CVCL, and to a less degree MCA and THL. To achieve more stable results among observers, a still lacking standardized measurement protocol could be helpful.

11.
PeerJ ; 9: e11039, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33854841

RESUMO

BACKGROUND: Quantifying variation of genetic traits over the geographical range of species is crucial for understanding the factors driving their range dynamics. The center-periphery hypothesis postulates, and many studies support, the idea that genetic diversity decreases and genetic differentiation increases toward the geographical periphery due to population isolation. The effects of environmental marginality on genetic variation has however received much less attention. METHODS: We tested the concordance between geographical and environmental gradients and the genetic predictions of center-periphery hypothesis for endemic Lilium pomponium in the southern Alps. RESULTS: We found little evidence for concordance between genetic variation and both geographical and environmental gradients. Although the prediction of increased differentiation at range limits is met, genetic diversity does not decrease towards the geographical periphery. Increased differentiation among peripheral populations, that are not ecologically marginal, may be explained by a decrease in habitat availability that reduces population connectivity. In contrast, a decrease of genetic diversity along environmental but not geographical gradients may be due to the presence of low quality habitats in the different parts of the range of a species that reduce effective population size or increase environmental constraints. As a result, environmental factors may affect population dynamics irrespective of distance from the geographical center of the range. In such situations of discordance between geographical and environmental gradients, the predictions of decreasing genetic diversity and increasing differentiation toward the geographical periphery may not be respected.

12.
Rev. méd. Urug ; 39(3): e203, sept. 2023.
Artigo em Espanhol | LILACS, BNUY | ID: biblio-1508731

RESUMO

Introducción: la crisis sanitaria por COVID-19 impactó en la atención de diversas patologías, entre ellas, el cáncer. Con el fin de disminuir el riesgo de contraer SARS-CoV-2 se redujo el número de consultas, lo que determinó un aumento en la tasa de morbilidad y mortalidad para otras patologías, lo que se ha denominado la "segunda pandemia". Objetivo: describir la actividad asistencial de la Unidad de Mastología (UM) en el período marzo 2020 - marzo 2022 y compararla con la del período marzo 2019 - marzo 2021. Objetivo: describir la actividad asistencial de la Unidad de Mastología (UM) en el período marzo 2020 - marzo 2022 y compararla con la del período marzo 2019 - marzo 2021. Material y método: estudio observacional retrospectivo que incluyó a pacientes asistidas por cáncer de mama (CM) en el período marzo 2019 - marzo 2022. Resultados: durante el año previo a la pandemia se asistieron 30 nuevas pacientes. En cuanto al tiempo entre el diagnóstico anatomopatológico y el primer tratamiento, en 73,3% fue ≤ 2 meses, 16,6% > 2 meses y ≤ 4 meses y en 10% fue > 4 meses. Durante la pandemia se asistieron 50 pacientes nuevas, lo que se traduce en un descenso de 16,6%. En cuanto al tiempo entre el diagnóstico anatomopatológico y el primer tratamiento: en 41% fue ≤ 2 meses, 33% > 2 meses y ≤ 4 meses y en 25% fue > 4 meses. Conclusiones: si bien se logró mantener la actividad asistencial y dar continuidad a la mayoría de los tratamientos, durante la pandemia COVID-19 se redujo el número de pacientes derivadas al servicio en aproximadamente 16,6% y se produjo un aumento en el tiempo transcurrido entre el diagnóstico y el primer tratamiento.


Introduction: the COVID-19 health crisis had a significant impact on the management of various pathologies, including cancer. To reduce the risk of contracting SARS-CoV-2, the number of consultations was reduced, leading to increased morbidity and mortality rates for other pathologies, which has been referred to as the "second pandemic." Objective: The aim of this study is to describe the clinical activity of the Breast Unit (BU) during the period March 2020-2022 and compare it with the activity during the period March 2019-2021. Objective: the aim of this study is to describe the clinical activity of the Breast Unit (BU) during the period March 2020-2022 and compare it with the activity during the period March 2019-2021. Method: retrospective observational study including patients attending the BU during the period March 2019-2022. Results: in the year before the pandemic, 30 new patients were assisted. Regarding the time between anatomopathological diagnosis and the initiation of the first treatment: in 73.3% of cases, it was ≤ 2 months, 16.6% > 2 months and ≤ 4 months, and in 10%, it was > 4 months. During the pandemic, 50 new patients were assisted, representing a decrease of approximately 16.6% in the number of new patients attended. Regarding the time between anatomopathological diagnosis and the initiation of the first treatment: in 41% of cases, it was ≤ 2 months, 33% > 2 months and ≤ 4 months, and in 25%, it was > 4 months. Conclusion: although the BU managed to maintain its clinical activity and continuity of most treatments during the COVID pandemic, there was a reduction in the number of patients referred to the service by approximately 16.6% and an increase in the time elapsed between diagnosis and the initiation of the first treatment.


Introdução: a crise sanitária causada pela COVID-19 impactou o atendimento de diversas patologias, inclusive o câncer. Para diminuir o risco de contrair SARS-CoV-2, reduziu-se o número de consultas, o que determinou um aumento da taxa de morbimortalidade por outras patologias, o que tem sido chamado de "segunda pandemia". Objetivo: descrever a atividade assistencial da Unidade de Mastologia (UM) no período março de 2020 - março de 2022 e compará-la com a do período março de 2019 - março de 2020. Material e método: estudo observacional retrospectivo que incluiu pacientes atendidos pelo CM no período março de 2019 - março de 2022. Resultados: no ano anterior à pandemia foram atendidos 30 novos pacientes. Em relação ao tempo entre o diagnóstico patológico e o primeiro tratamento: em 73,3% foi ≤2 meses, 16,6% >2 meses e ≤4 meses e em 10% foi >4 meses. Durante a pandemia, foram atendidos 50 novos pacientes, o que se traduz em uma queda de 16,6%no número de novos pacientes atendidos. Quanto ao tempo entre o diagnóstico patológico e o primeiro tratamento: em 41% foi ≤2 meses, 33% >2 meses e ≤4 meses e em 25% foi >4 meses. Conclusão: embora tenha conseguido manter a atividade assistencial e dar continuidade à maioria dos tratamentos, durante a pandemia de COVID-19 o número de pacientes encaminhados para o Serviço diminuiu cerca de 16,6% e houve um aumento do tempo decorrido entre o diagnóstico e o primeiro tratamento.


Assuntos
Neoplasias da Mama , Atenção à Saúde , Avaliação do Impacto na Saúde , COVID-19
13.
PLoS One ; 12(2): e0171866, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28192471

RESUMO

Berardia subacaulis Vill. is a monospecific genus that is endemic to the South-western Alps, where it grows on alpine screes, which are extreme habitats characterized by soil disturbance and limiting growth conditions. Root colonization by arbuscular mycorrhizal fungi (AMF) is presumably of great importance in these environments, because of its positive effect on plant nutrition and stress tolerance, as well as on structuring the soil. However, there is currently a lack of information on this topic. In this paper, we tested which soil characteristics and biotic factors could contribute to determining the abundance and community composition of AMF in the roots of B. subacaulis, which had previously been found to be mycorrhizal. For such a reason, the influence of soil properties and environmental factors on AMF abundance and community composition in the roots of B. subacaulis, sampled on three different scree slopes, were analysed through microscopic and molecular analysis. The results have shown that the AMF community of Berardia roots was dominated by Glomeraceae, and included a core of AMF taxa, common to all three scree slopes. The vegetation coverage and dark septate endophytes were not related to the AMF colonization percentage and plant community did not influence the root AMF composition. The abundance of AMF in the roots was related to some chemical (available extractable calcium and potassium) and physical (cation exchange capacity, electrical conductivity and field capacity) properties of the soil, thus suggesting an effect of AMF on improving the soil quality. The non-metric multidimensional scaling (NMDS) ordination of the AMF community composition showed that the diversity of AMF in the various sites was influenced not only by the soil quality, but also by the slope. Therefore, the slope-induced physical disturbance of alpine screes may contribute to the selection of disturbance-tolerant AMF taxa, which in turn may lead to different plant-fungus assemblages.


Assuntos
Asteraceae/microbiologia , Ecossistema , Micorrizas/fisiologia , Solo/química , Altitude , Endófitos/fisiologia , França , Variação Genética , Geografia , Itália , Micorrizas/classificação , Micorrizas/genética , Filogenia , Raízes de Plantas/microbiologia , Densidade Demográfica , Dinâmica Populacional , Microbiologia do Solo
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