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Although plant-soil feedback (PSF) is being recognized as an important driver of plant recruitment, our understanding of its role in species coexistence in natural communities remains limited by the scarcity of experimental studies on multispecies assemblages. Here, we experimentally estimated PSFs affecting seedling recruitment in 10 co-occurring Mediterranean woody species. We estimated weak but significant species-specific feedback. Pairwise PSFs impose similarly strong fitness differences and stabilizing-destabilizing forces, most often impeding species coexistence. Moreover, a model of community dynamics driven exclusively by PSFs suggests that few species would coexist stably, the largest assemblage with no more than six species. Thus, PSFs alone do not suffice to explain coexistence in the studied community. A topological analysis of all subcommunities in the interaction network shows that full intransitivity (with all species involved in an intransitive loop) would be rare but it would lead to species coexistence through either stable or cyclic dynamics.

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AIMS: To evaluate the knowledge, attitudes, and practical skills of students submitted to a 6-week intensive training in epilepsy compared to students without any training but mandatory neurology classes. METHODS: It is a case-control study. After completing a 6-week intensive Academic, Clinical, and Research Program in epilepsy, TUMSs answered a validated Knowledge Attitudes and Practices (KAP) questionnaire. The control group, composed of undergraduate students who shared the same age, academic year, and compulsory hours for learning about epilepsy as TUMSs, was also assessed through the KAP instrument. Answers from both groups were submitted to Fisher exact and the χ2 test to observe differences among groups. Descriptive statistics were also performed. RESULTS: TUMSs displayed better results in theoretical knowledge such as the definition and causes of epilepsy, and the application of paraclinical studies essential for diagnosing epilepsy. From their perspective, people with epilepsy encounter restricted opportunities for preserving their social life and employment and they are more prone to workplace accidents. They are convinced that facing epilepsy presents a notable risk due to the difficulties linked with diagnosis, considering epilepsy a challenging disease for general practitioners to identify and follow up. Likewise, they exhibited improvement in treatment adjustment and treatment monitoring of patients with epilepsy, mainly in pregnancy cases. Finally, they had greater knowledge about what to do when they witness a person experiencing a seizure. CONCLUSION: Our study showed that a 6-week intensive education program in epilepsy increased the knowledge and practical skills and changed the attitude toward patients with epilepsy of undergraduate students.

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Mendelian Susceptibility to Mycobacterial Disease describes a spectrum of inherited defects, of which complete deficiency of the interleukin-12 receptor ß subunit 1 (IL-12Rß1) is the most common cause. This condition results in a predisposition to severe disease caused by mycobacteria. We report a case of disseminated multidrug-resistant tuberculosis with extensive central nervous system affection with SARS-CoV-2 co-infection, in a 4-year-old child with IL-12Rß1 complete deficiency.

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Plant recruitment interactions (i.e., what recruits under what) shape the composition, diversity, and structure of plant communities. Despite the huge body of knowledge on the mechanisms underlying recruitment interactions among species, we still know little about the structure of the recruitment networks emerging in ecological communities. Modeling and analyzing the community-level structure of plant recruitment interactions as a complex network can provide relevant information on ecological and evolutionary processes acting both at the species and ecosystem levels. We report a data set containing 143 plant recruitment networks in 23 countries across five continents, including temperate and tropical ecosystems. Each network identifies the species under which another species recruits. All networks report the number of recruits (i.e., individuals) per species. The data set includes >850,000 recruiting individuals involved in 118,411 paired interactions among 3318 vascular plant species across the globe. The cover of canopy species and open ground is also provided. Three sampling protocols were used: (1) The Recruitment Network (RN) protocol (106 networks) focuses on interactions among established plants ("canopy species") and plants in their early stages of recruitment ("recruit species"). A series of plots was delimited within a locality, and all the individuals recruiting and their canopy species were identified; (2) The paired Canopy-Open (pCO) protocol (26 networks) consists in locating a potential canopy plant and identifying recruiting individuals under the canopy and in a nearby open space of the same area; (3) The Georeferenced plot (GP) protocol (11 networks) consists in using information from georeferenced individual plants in large plots to infer canopy-recruit interactions. Some networks incorporate data for both herbs and woody species, whereas others focus exclusively on woody species. The location of each study site, geographical coordinates, country, locality, responsible author, sampling dates, sampling method, and life habits of both canopy and recruit species are provided. This database will allow researchers to test ecological, biogeographical, and evolutionary hypotheses related to plant recruitment interactions. There are no copyright restrictions on the data set; please cite this data paper when using these data in publications.

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The origins of agriculture were key events in human history, during which people came to depend for their food on small numbers of animal and plant species. However, the biological traits determining which species were domesticated for food provision, and which were not, are unclear. Here, we investigate the phylogenetic distribution of livestock and crops, and compare their phenotypic traits with those of wild species. Our results indicate that phylogenetic clustering is modest for crop species but more intense for livestock. Domesticated species explore a reduced portion of the phenotypic space occupied by their wild counterparts and have particular traits in common. For example, herbaceous crops are globally characterized by traits including high leaf nitrogen concentration and tall canopies, which make them fast-growing species and proficient competitors. Livestock species are relatively large mammals with low basal metabolic rates, which indicate moderate to slow life histories. Our study therefore reveals ecological differences in domestication potential between plants and mammals. Domesticated plants belong to clades with traits that are advantageous in intensively managed high-resource habitats, whereas domesticated mammals are from clades adapted to moderately productive environments. Combining comparative phylogenetic methods with ecologically relevant traits has proven useful to unravel the causes and consequences of domestication.

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BACKGROUND: Extranodal natural killer/T-cell lymphoma, nasal type (ENKTL) is an aggressive lymphoma with a very low incidence in western populations. OBJECTIVE: To review the clinicopathological features and outcome of a multicentre series of ENKTL in Spain. MATERIALS & METHODS: A multicentre retrospective study was performed based on cases of ENKTL, collected from 1995 to 2004, from 12 dermatology departments included in the Spanish Lymphoma Study Group. The clinical, histopathological, and evolutive features of all these cases were reviewed. RESULTS: Eighteen patients (three male, 15 female) with median age of 67 years were included in the study. The onset of lesions occurred in the nasal region in 11 patients and on the skin outside this region in the remaining cases. The observed lesions were clinically heterogeneous, corresponding to papules, plaques, and nodules, with or without ulceration. All patients except four received different polychemotherapy regimens, either alone (n = 11) or in combination with radiotherapy (n = 4). After a variable follow-up period (1-36 months), only two patients remained alive. One patient was recently diagnosed (four months ago) with ENKTL in the nasal region and the other presented with skin-limited disease. The median overall survival was 9.5 months. CONCLUSIONS: The results of this retrospective survey confirm that ENKTL is a rare subtype of lymphoma in the Spanish population. All patients showed an aggressive clinical course and poor prognosis, regardless of the initial clinical presentation. Prospective data on larger series of patients treated homogenously are needed to establish the best treatment modality.

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PREMISE OF THE STUDY: Microsatellite primers were developed to characterize and evaluate patterns of genetic diversity and structure in the endangered Mediterranean shrub Ziziphus lotus (Rhamnaceae). METHODS AND RESULTS: Twenty microsatellite primers were developed for Z. lotus, of which 14 were polymorphic. We evaluated microsatellite polymorphism in 97 specimens from 18 Spanish and seven Moroccan populations. Between two and eight alleles were found per locus, and the average number of alleles was 5.54. Observed heterozygosity and expected heterozygosity ranged from 0.08 to 0.90 and from 0.08 to 0.82, respectively. Nine of these primers also amplified microsatellite loci in Z. jujuba. CONCLUSIONS: The microsatellite markers described here will be useful in studies on genetic variation, population genetic structure, and gene flow in the fragmented habitat of this species. These markers are a valuable resource for designing appropriate conservation measures for the species in the Mediterranean range.

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The idea of pollination syndromes has been largely discussed but no formal quantitative evaluation has yet been conducted across angiosperms. We present the first systematic review of pollination syndromes that quantitatively tests whether the most effective pollinators for a species can be inferred from suites of floral traits for 417 plant species. Our results support the syndrome concept, indicating that convergent floral evolution is driven by adaptation to the most effective pollinator group. The predictability of pollination syndromes is greater in pollinator-dependent species and in plants from tropical regions. Many plant species also have secondary pollinators that generally correspond to the ancestral pollinators documented in evolutionary studies. We discuss the utility and limitations of pollination syndromes and the role of secondary pollinators to understand floral ecology and evolution.

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A central issue in ecology is the understanding of the establishment of biotic interactions. We studied the factors that affect the assembly of the commensalistic interactions between vascular epiphytes and their host plants. We used an analytical approach that considers all individuals and species of epiphytic bromeliads and woody hosts and non-hosts at study plots. We built models of interaction probabilities among species to assess if host traits and abundance and spatial overlap of species predict the quantitative epiphyte-host network. Species abundance, species spatial overlap and host size largely predicted pairwise interactions and several network metrics. Wood density and bark texture of hosts also contributed to explain network structure. Epiphytes were more common on large hosts, on abundant woody species, with denser wood and/or rougher bark. The network had a low level of specialization, although several interactions were more frequent than expected by the models. We did not detect a phylogenetic signal on the network structure. The effect of host size on the establishment of epiphytes indicates that mature forests are necessary to preserve diverse bromeliad communities.

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Glandular trichomes play a defensive role against herbivores in the leaves of many plant species. However, their functional role in inflorescences has not been studied, even though theory suggests that tissues with a higher fitness value, such as inflorescences, should be better defended. Using manipulative experiments, we analysed the defensive role of glandular trichomes against herbivorous insects in the inflorescence of Iberian columbines (genus Aquilegia), and its inter-population and inter-taxa variation in relation to herbivore abundance and potential selective pressure. The experiments were conducted in eight populations belonging to four subspecies of two columbines (Aquilegia vulgaris and Aquilegia pyrenaica). For each population, we estimated the density of glandular trichomes in the inflorescences, the abundance of insects stuck in the inflorescences, the abundance of small herbivorous insects, the incidence of damage on flowers and fruits, and the fruit set. The density of glandular trichomes on the inflorescence of A. vulgaris and A. pyrenaica was higher in regions of higher herbivore abundance. We also found that when the plants lose the protection of glandular trichomes, small insects have better access to flowers and fruits, causing more damage and reducing plant fitness. This study concludes that glandular trichomes are part of an adaptive response against phytophagous insect herbivory. The observed variation in herbivore pressure between taxa, likely caused by habitat differentiation, might have played a role in trait differentiation through divergent selection. This result adds evidence to the differentiation of the Iberian columbines through habitat specialization.

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Folliculitis decalvans is an embarrassing and challenging disease with no established treatment guidelines. In this paper, we described four patients with this disease treated successfully with Tacrolimus ointment. All of them showed significant control of the condition, stopping inflammatory lesions and progression of the disease, although weak transitory outbreaks of inflammatory lesions were observed in some cases. Alopecia and tufted hairs remained unchanged. The discontinuation of the therapy produced rapid relapses in all cases. Close monitoring of these patients is recommended due to the potential risk of malignant transformation of the disease.

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• The ecological and adaptive significance of plant polyploidization is not well understood and no clear pattern of association between polyploid frequency and environment has emerged. Climatic factors are expected to predict cytotype distribution. However, the relationship among climate, cytotype distribution and variation of abiotic stress tolerance traits has rarely been examined. • Here, we use flow cytometry and root-tip squashes to examine the cytotype distribution in the temperate annual grass Brachypodium distachyon in 57 natural populations distributed across an aridity gradient in the Iberian Peninsula. We further investigate the link between environmental aridity, ploidy, and variation of drought tolerance and drought avoidance (flowering time) traits. • Distribution of diploids (2n = 10) and allotetraploids (2n = 30) in this species is geographically structured throughout its range in the Iberian Peninsula, and is associated with aridity gradients. Importantly, after controlling for geographic and altitudinal effects, the link between aridity and polyploidization occurrence persisted. Water-use efficiency varied between ploidy levels, with tetraploids being more efficient in the use of water than diploids under water-restricted growing conditions. • Our results indicate that aridity is an important predictor of polyploid occurrence in B. distachyon, suggesting a possible adaptive origin of the cytotype segregation.

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Leukemia cutis is defined as a skin infiltration by leukemic cells. The diagnosis of myeloid leukemia cutis (MLC) can represent a challenge, especially in those cases without symptoms of systemic disease. The clinical appearance, histopathological analysis and immunohistochemical profile can be indistinguishable from those observed in cases of hystiocitoid Sweet syndrome (HSS). We present a case of MLC in which the cutaneous affectation was the first sign of the systemic leukemia. In this setting, the myeloperoxidase stain was the clue to rule out the possibility of HSS. We discuss the role and the utility of the myeloperoxidase stain in the differentiation of these two entities.

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Measuring heritable genetic variation is important for understanding patterns of trait evolution in wild populations, and yet studies of quantitative genetic parameters estimated directly in the field are limited by logistic constraints, such as the difficulties of inferring relatedness among individuals in the wild. Marker-based approaches have received attention because they can potentially be applied directly to wild populations. For long-lived, self-compatible plant species where pedigrees are inadequate, the regression-based method proposed by Ritland has the appeal of estimating heritabilities from marker-based estimates of relatedness. The method has been difficult to implement in some plant populations, however, because it requires significant variance in relatedness across the population. Here, we show that the method can be readily applied to compare the ability of different traits to respond to selection, within populations. For several taxa of the perennial herb genus Aquilegia, we estimated heritabilities of floral and vegetative traits and, combined with estimates of natural selection, compared the ability to respond to selection of both types of traits under current conditions. The intra-population comparisons showed that vegetative traits have a higher potential for evolution, because although they are as heritable as floral traits, selection on them is stronger. These patterns of potential evolution are consistent with macroevolutionary trends in the European lineage of the genus.

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Multiple cutaneous and uterine leiomyomatosis (MCUL; OMIM 150800) is an autosomal dominantly inherited disease characterized by leiomyomas of the skin and uterine leiomyomas. Recently, association of MCUL with different forms of renal cancer has been described. This syndrome is referred to as hereditary leiomyomatosis and renal cell cancer (OMIM 605839). Both disorders result from heterozygous germline mutations in the fumarate hydratase (FH) gene that may function as a tumor suppressor. Interestingly, cutaneous leiomyomas do not only manifest in a diffuse and symmetric fashion. Rather frequently, a segmental or band-like manifestation pattern can be observed, usually following the lines of Blaschko. Here, we sought to elucidate the molecular basis of diffuse and segmental cutaneous leiomyomatosis in six unrelated Dutch and Spanish patients and their families. We identified six novel FH mutations, including one missense and one nonsense mutation, two deletions and two splice-site mutations. The segmental phenotype that was observed in various patients with FH mutations most likely reflects a type 2 segmental manifestation of cutaneous leiomyomatosis as previously also described for other autosomal dominantly inherited skin diseases. The results presented here extend the current data on the molecular basis of familial cutaneous leiomyomatosis and comprise, to the best of our knowledge, the first genetic study in Dutch and Spanish patients with this disorder. In addition, we review the clinical and molecular aspects of the disease.

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