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Background: Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is the most common familial cerebral small vessel disease, caused by NOTCH3 gene mutations. The aim of our study was to identify clinical and neuroradiological features which would be useful in identifying which patients presenting with lacunar stroke and TIA are likely to have CADASIL., Methods: Patients with lacunar stroke or TIA were included in the present study. For each patient, demographic and clinical data were collected. MRI images were centrally analysed for the presence of lacunar infarcts, microbleeds, temporal lobe involvement, global atrophy and white matter hyperintensities., Results: 128 patients (mean age 56.3 ± 12.4 years) were included. A NOTCH3 mutation was found in 12.5% of them. A family history of stroke, the presence of dementia and external capsule lesions on MRI were the only features significantly associated with the diagnosis of CADASIL. Although thalamic, temporal pole gliosis and severe white matter hyperintensities were less specific for CADASIL diagnosis, the combination of a number of these factors together with familial history for stroke result in a higher positive predictive value and specificity., Conclusions: A careful familial history collection and neuroradiological assessment can identify patients in whom NOTCH3 genetic testing has a higher yield.

Aims: The bioactivities of Santolina corsica Jord. & Fourr. n-hexane (EHS) and methanol (EMS) extracts were evaluated in relation to their chemical profile., Main Methods: EHS and EMS were analysed by gas chromatography-mass spectrometry () and high performance liquid chromatography-diode array detection (HPLC-DAD), respectively. Antioxidant activity was determined by β-carotene bleaching, Ferric Reducing Activity Power (FRAP), 2,2-diphenyl-1-picrylhydrazyl (DPPH), and 2,2'-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid (ABTS) tests. Nitric oxide (NO) production was assessed in LPS-stimulated RAW 264.7 cells. Anti-proliferative activity was evaluated by MTT assay on A549, HeLa, PC3, MCF-7, MDA-MB-231 cancer cells, and non-tumorigenic MCF10 A cells. Cell motility, migration and invasion were assessed by wound-healing scratch, migration and invasion assays, respectively. DNA fragmentation was tested by TUNEL assay. Cells morphology was studied by phase-contrast microscopy. Procaspase-8, -9, poly (ADP-ribose) polymerase and COX-2 expression levels were evaluated by immunoblotting analysis., Key Findings: Kaempferol-3-O-glucoside (5878.67 mg/100 g of extract), chlorogenic acid (746.11 mg/100 g), and rosmarinic acid (550.16 mg/100 g) were the dominant EMS constituents. EHS showed myrcene (18.86%) as the main compound, followed by palmitic acid methyl and ethyl esters (9.35 and 9.16%, respectively), β-phellandrene (8.48%), and ar-curcumene (5.63%). Both extracts showed promising anti-proliferative activity on all tested cancer cells, without inducing cytotoxicity in non-tumorigenic cells MCF-10 A. Moreover, extracts inhibited motility, migration, and invasion of MDA-MB-231 cells, inducing apoptosis. EHS decreased NO production, showing anti-inflammatory activity., Significance: S. corsica extracts might be potentially useful in cancer treatment, since reduce invasive and migratory potential of MDA-MB-231 cells triggering apoptosis., (Copyright © 2018 Elsevier Masson SAS. All rights reserved.)

As variations in the chromosome number are recognized to be of evolutionary interest but are also widely debated in the literature, we aimed to quantitatively test for possible relationships among the chromosome number, plant traits, and environmental factors. In particular, the chromosome number and drivers of its variation were examined in 801 Italian endemic vascular plants, for a total of 1364 accessions. We estimated phylogenetic inertia and adaptation in chromosome number - based on an Ornstein-Uhlenbeck process - and related chromosome numbers with other plant traits and environmental variables. Phylogenetic effects in chromosome number varied among the examined clades but were generally high. Chromosome numbers were poorly related to large scale climatic conditions, while a stronger relationship with categorical variables was found. Specifically, open, disturbed, drought-prone habitats selected for low chromosome numbers, while perennial herbs, living in shaded, stable environments were associated with high chromosome numbers. Altogether, our findings support an evolutionary role of chromosome number variation, and we argue that environmental stability favours higher recombination rates in comparison to unstable environments. In addition, by comparing the results of models testing for the evolvability of 2n and of x, we provide insight into the presumptive ecological significance of polyploidy.

Background: Spontaneous intracerebral haemorrhage (ICH) is a relatively common fatal disease, with an overall global incidence estimated at 24.6 per 100,000 person- years. Given the high degree of morbidity and mortality associated with ICH, therapies that may have neuroprotective effects are of increasing interest to clinicians. In this last context, cell therapies offer the promise of improving the disease course which cannot be addressed adequately by existing treatments., Objective: The aim of this review is to evaluate the protective effects and molecular mechanisms of mesenchymal stem cells (MSCs) on haemorrhagic brain following ICH. We also discuss possible emerging therapeutic approaches worth of further research., Methods and Results: The available literature on the therapeutic potential of MSCs in ICH animal models clearly demonstrated that MSCs enhance the functional recovery and reduce the volume of the infarct size exerting anti-inflammatory and angiogenic properties. However, the quality of the original articles investigating the efficacy of stem cell therapies in ICH animal models is still poor and the lack of ICH clinical trial does not permit to reach any relevant conclusions., Conclusion: Further studies have to be implemented in order to achieve standardized methods of MSCs isolation, characterization and administration to improve ICH treatments with MSCs or MSC-derived products., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.)

Background: Several methodologies including neuroimaging and sleep evaluation are being developed to complement the clinical bedside examinations in patients with disorder of consciousness (DOC). Recently, we demonstrated a possible association between Period3 (Per3) variable number tandem repeat (VNTR) polymorphism and functional impairment of DOC patients, speculating a possible role of this gene in sleep regulation., Aim: To assess whether the degree of structural and metabolic damage of the main brain areas involved in the sleep generation and homeostasis may influence the different outcome of DOC patients carrying the Per3 5/5 genotype in comparison to Per3 4/4 ones., Methods: For the present study, we reviewed 44 DOC patients from the Coma Research Centre of the Fondazione IRCCS Istituto Neurologico "C. Besta" of Milan. All patients underwent to polysomnographic sleep evaluation, cerebral structural magnetic resonance imaging (MRI) and 18 F-fluoro-2-deoxyglucose positron emission tomography (FDG-PET) analysis., Results: Our DOC patients presented a moderate anatomical (median score 2) and metabolic damage (median value 2.36 SUVmean) of the sleep areas at both MRI and FDG-PET evaluation. Total sleep time seemed to be higher in 5/5 genotype DOC patients (median value Per3 5/5 , 221min, range 126-323min; median value Per3 4/4 , 167min, range 36-477min; and median value Per3 4/5 , 187min, range 29-422min). However, the MRI scores and FDG-PET values of whole brain, overall sleep areas, hypothalamus, midbrain and thalamus did not differ by genotype distribution., Conclusion: Although limited by the small sample size, our data might support the idea that Per3 genetic predisposition in DOC patients could affect impairment and residual cognitive functions through sleep homeostasis independently from structural and/or metabolic integrity of sleep areas., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Opinion Statement: CADASIL is a life-threatening and disabling disease. Despite the progress achieved so far, no therapies able to limit the disease progression have been found and only empiric treatments can be employed to relieve the main disease symptoms. Further in vivo studies as well as data aggregation and multi-centre controlled clinical trials are needed to confirm the emerging findings in order to identify evidence-based therapies for CADASIL.

The complex architecture of adult brain derives from tightly regulated migration and differentiation of precursor cells generated during embryonic neurogenesis. Changes at transcriptional level of genes that regulate migration and differentiation may lead to neurodevelopmental disorders. Androgen receptor (AR) is a transcription factor that is already expressed during early embryonic days. However, AR role in the regulation of gene expression at early embryonic stage is yet to be determinate. Long non-coding RNA (lncRNA) Sox2 overlapping transcript (Sox2OT) plays a crucial role in gene expression control during development but its transcriptional regulation is still to be clearly defined. Here, using Bicalutamide in order to pharmacologically inactivated AR, we investigated whether AR participates in the regulation of the transcription of the lncRNASox2OTat early embryonic stage. We identified a new DNA binding region upstream of Sox2 locus containing three androgen response elements (ARE), and found that AR binds such a sequence in embryonic neural stem cells and in mouse embryonic brain. Our data suggest that through this binding, AR can promote the RNA polymerase II dependent transcription of Sox2OT. Our findings also suggest that AR participates in embryonic neurogenesis through transcriptional control of the long non-coding RNA Sox2OT.

Moyamoya disease is a rare steno-occlusive cerebrovascular disorder often resulting in hemorrhagic and ischemic strokes. Although sharing the same ischemic stimulus with atherosclerotic cerebrovascular disease, Moyamoya disease is characterized by a highly instable cerebrovascular system which is prone to rupture due to pathological neovascularization. To understand the molecular mechanisms underlying this instability, angiopoietin-2 gene expression was analyzed in middle cerebral artery lesions obtained from Moyamoya disease and atherosclerotic cerebrovascular disease patients. Angiopoietin-2 was significantly up-regulated in Moyamoya vessels, while serum concentrations of soluble angiopoietins were not changed. For further evaluations, cerebral endothelial cells incubated with serum from these patients in vitro were applied. In contrast to atherosclerotic cerebrovascular disease serum, Moyamoya disease serum induced an angiopoietin-2 overexpression and secretion, accompanied by loss of endothelial integrity. These effects were absent or inverse in endothelial cells of non-brain origin suggesting brain endothelium specificity. The destabilizing effects on brain endothelial cells to Moyamoya disease serum were partially suppressed by the inhibition of angiopoietin-2. Our findings define brain endothelial cells as the potential source of vessel-destabilizing factors inducing the high plasticity state and disintegration in Moyamoya disease in an autocrine manner. We also provide new insights into Moyamoya disease pathophysiology that may be helpful for preventive treatment strategies in future.

Ethnopharmacological Relevance: Wild foods constitute an essential component of people's diets around the world, but despite their widespread use and their cultural importance, wild edible plants (WEPs) lack recognition as significant contributors to the human diet in developed countries., Materials and Methods: We stimulate national and international bodies dealing with food and agriculture, to increase their attention and investments on WEPs, leveraging the results of scientific investigation, enhancing the link between in situ conservation strategies and sustainable use of plant genetic diversity., Results and Conclusions: WEPs should be reconsidered throughout their value chain, capturing their important socio-cultural, health, and economic benefits to indigenous and local communities and family farmers who are engaged in their production and wild-harvesting., (Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.)

Opinion Statement: Fabry disease is an X-linked, lysosomal storage disorder caused by a mutation in the GLA gene leading to a deficiency in alpha-galactosidase A enzyme (α-Gal A) activity, which in turn results in accumulation of globotriaosylceramide in the vascular endothelium and smooth muscle cells of different organs, including kidney and heart, finally leading to impairment or failure of organ function. The central and peripheral nervous systems are also affected leading to neurological manifestations such as cerebrovascular diseases, small fiber neuropathy (SFN), and dysautonomic disorders that may be the presenting clinical features in a proportion of patients. This review offers a complete update of all neurological aspects of Fabry disease and therapeutic options. The rarity of disease, as well as the incomplete knowledge regarding natural history, pathogenic mechanisms, and the uncertain efficacy of available therapies, make imperative the acquisition of standardized data on natural disease course. These data are fundamental for the development of new treatments better able to access the central nervous system, to bypass the neutralizing antibodies and to improve the heart and kidney function.

Background Sleep evaluation is increasingly being used as prognostic tool in patients with disorders of consciousness, but, surprisingly, the role of Period3 (Per3) gene polymorphism has never been evaluated. Objective The aim of this study was to investigate the contribution of Per3 genotype on sleep quantity and consciousness recovery level in patients with disorders of consciousness (DOC). Methods In this observational study, we evaluated 71 patients with DOC classified as vegetative state/unresponsive wakefulness syndrome or minimally conscious state. Demographic and clinical data were collected and a standardised diagnostic workup, including a polysomnographic record, was applied. After informed consent provided by proxy, genomic DNA was obtained and Per3 polymorphism was analysed by polymerase chain reaction to identify 5/5, 4/5, or 4/4 genotype. Results Per3(5/5) genotype was found in 12.7% of our DOC patients. The median total Coma Recovery Scale-revised score in Per3(5/5) carriers was significantly higher than 4/4 genotype (10, range 5-16 vs 7, range 4-11; post hoc P = .036). Moreover, total sleep time seemed to be higher in 5/5 genotype (5/5, 221 minutes, range 88-515 minutes; 4/4, 151.5 minutes, range 36-477 minutes; and 4/5, 188 minutes, range 44-422 minutes). Conclusion For the first time we have shown a possible association between Per3 polymorphism and consciousness recovery level in DOC patients. Even though the exact molecular mechanism has not been defined, we speculate that its effect is mediated by higher total sleep time and slow wave sleep, which would improve the preservation of main cerebral connections., (© The Author(s) 2015.)

Divry van Bogaert Syndrome (DBS) is a familial juvenile-onset disorder characterized by livedo racemosa, white matter disease, dementia, epilepsy and angiographic finding of "cerebral angiomatosis". A similar syndrome including livedo racemosa and cerebrovascular disease, often associated with anticardiolipin antibodies, has been described as Sneddon Syndrome (SS) highlighting the question whether these two conditions have to be considered different entities or indeed different features of a unique syndrome. Herein, we report the clinical, neuroradiological, histopathological findings and follow up of three cases diagnosed as Divry-van Bogaert Syndrome, including an updated review of literature of both DBS and SS cases. Our findings support the assumption that DBS and SS are different disease entities. DBS is characterized by the typical angiographic feature of angiomatosis, a hereditary trait and a juvenile onset of cognitive impairment and leukoaraiosis, whereas SS has less severe manifestations of cerebrovascular disease associated with livedo racemosa but without the characteristic cerebral angiography. The report of our cases and the literature review underline the necessity of a detailed work-up and the collection of larger series to better clarify the DBS and SS phenotype and course., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Background: Moyamoya disease (MMD) is a slowly progressing steno-occlusive cerebrovascular disease. The typical moyamoya vessels, which originate from an initial stenosis of the internal carotid, highlight that increased and/or abnormal angiogenic, vasculogenic and arteriogenic processes are involved in the disease pathophysiology., Objective: Herein, we summarize the current knowledge on the most important signaling pathways involved in MMD vessel formation, particularly focusing on the expression of growth factors and function of endothelial progenitor cells (EPCs)., Methods and Results: Higher plasma concentrations of vascular endothelial growth factor, matrix metalloproteinase, hepatocyte growth factor, and interleukin-1β were reported in MMD. A specific higher level of basic fibroblast growth factor was also found in the cerebrospinal fluid of these patients. Finally, the number and the functionality of EPCs were found to be increased. In spite of the available data, the approaches and findings reported so far do not give an evident correlation between the expression levels of the aforementioned growth factors and MMD severity. Furthermore, the controversial results provided by studies on EPCs, do not permit to understand the true involvement of these cells in MMD pathophysiology., Conclusion: Further studies should thus be implemented to extend our knowledge on processes regulating both the arterial stenosis and the excessive formation of collateral vessels. Moreover, we suggest advances of integrated approaches and functional assays to correlate biological and clinical data, arguing for the development of new therapeutic applications for MMD.

Background: The pathogenesis of moyamoya disease (MMD) is still unknown. The detection of inflammatory molecules such as cytokines, chemokines and growth factors in MMD patients' biological fluids supports the hypothesis that an abnormal angiogenesis is implicated in MMD pathogenesis. However, it is unclear whether these anomalies are the consequences of the disease or rather causal factors as well as these mechanisms remain insufficient to explain the pathophysiology of MMD. The presence of a family history in about 9-15% of Asian patients, the highly variable incidence rate between different ethnic and sex groups and the age of onset support the role of genetic factors in MMD pathogenesis. However, although some genetic loci have been associated with MMD, few of them have been replicated in independent series. Recently, RNF213 gene was shown to be strongly associated with MMD occurrence with a founder effect in East Asian patients. However, the mechanisms leading from RNF213 mutations to MMD clinical features are still unknown., Summary: The research on pathogenic mechanism of MMD is in its infancy. MMD is probably a complex and heterogeneous disorder, including different phenotypes and genotypes, in which more than a single factor is implicated., Key Message: Since the diagnosis of MMD is rapidly increasing worldwide, the development of more efficient stratifying risk systems, including both clinical but also biological drivers became imperative to improve our ability of predict prognosis and to develop mechanism-tailored interventions., (© 2016 S. Karger AG, Basel.)

Spinal and bulbar muscular atrophy (SBMA) or Kennedy's disease is an X-linked CAG/polyglutamine expansion motoneuron disease, in which an elongated polyglutamine tract (polyQ) in the N-terminal androgen receptor (ARpolyQ) confers toxicity to this protein. Typical markers of SBMA disease are ARpolyQ intranuclear inclusions. These are generated after the ARpolyQ binds to its endogenous ligands, which promotes AR release from chaperones, activation and nuclear translocation, but also cell toxicity. The SBMA mouse models developed so far, and used in preclinical studies, all contain an expanded CAG repeat significantly longer than that of SBMA patients. Here, we propose the use of SBMA patients adipose-derived mesenchymal stem cells (MSCs) as a new human in vitro model to study ARpolyQ toxicity. These cells have the advantage to express only ARpolyQ, and not the wild type AR allele. Therefore, we isolated and characterized adipose-derived MSCs from three SBMA patients (ADSC from Kennedy's patients, ADSCK) and three control volunteers (ADSCs). We found that both ADSCs and ADSCKs express mesenchymal antigens, even if only ADSCs can differentiate into the three typical cell lineages (adipocytes, chondrocytes and osteocytes), whereas ADSCKs, from SBMA patients, showed a lower growth potential and differentiated only into adipocyte. Moreover, analysing AR expression on our mesenchymal cultures we found lower levels in all ADSCKs than ADSCs, possibly related to negative pressures exerted by toxic ARpolyQ in ADSCKs. In addition, with proteasome inhibition the ARpolyQ levels increased specifically in ADSCKs, inducing the formation of HSP70 and ubiquitin positive nuclear ARpolyQ inclusions. Considering all of this evidence, SBMA patients adipose-derived MSCs cultures should be considered an innovative in vitro human model to understand the molecular mechanisms of ARpolyQ toxicity and to test novel therapeutic approaches in SBMA.

Quantitative parameters have been used to characterize chromosome number (CN) variation. This gave us the idea to collect available data in various organisms and compare them, in order to verify if variation patterns differ between animal and plant groups and to quantify these patterns with an Index of CN Heterogeneity (ICNH), useful as a parameter to compare related taxonomical/geographical groups of organisms. To the best of our knowledge, this is the first attempt to compare CN variation in animal and plant groups with large datasets. The quantitative analysis allowed detecting significant differences among most groups of animals and plants. The most striking difference, however, is the close relationship between mean CN and SD restricted to plants, in which higher CN are also associated with a larger variation degree, possibly due to the well known genomic plasticity in this group and a propensity for polyploidization higher than in animals. The ICNH defined here can be easily calculated for both animal and plant groups based on commonly available data. It summarizes data accumulated in over a century of research and includes so-called anomalies like fB and fOCN, sometimes overlooked by researchers due to lack of a proper way of comparison., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Introduction: Silk fibroin (SF) scaffolds have been shown to be a suitable substrate for tissue engineering and to improve tissue regeneration when cellularized with mesenchymal stromal cells (MSCs). We here demonstrate, for the first time, that electrospun nanofibrous SF patches cellularized with human adipose-derived MSCs (Ad-MSCs-SF), or decellularized (D-Ad-MSCs-SF), are effective in the treatment of skin wounds, improving skin regeneration in db/db diabetic mice., Methods: The conformational and structural analyses of SF and D-Ad-MSCs-SF patches were performed by scanning electron microscopy, confocal microscopy, Fourier transform infrared spectroscopy and differential scanning calorimetry. Wounds were performed by a 5 mm punch biopsy tool on the mouse's back. Ad-MSCs-SF and D-Ad-MSCs-SF patches were transplanted and the efficacy of treatments was assessed by measuring the wound closure area, by histological examination and by gene expression profile. We further investigated the in vitro angiogenic properties of Ad-MSCs-SF and D-Ad-MSCs-SF patches by affecting migration of human umbilical vein endothelial cells (HUVECs), keratinocytes (KCs) and dermal fibroblasts (DFs), through the aortic ring assay and, finally, by evaluating the release of angiogenic factors., Results: We found that Ad-MSCs adhere and grow on SF, maintaining their phenotypic mesenchymal profile and differentiation capacity. Conformational and structural analyses on SF and D-Ad-MSCs-SF samples, showed that sterilization, decellularization, freezing and storing did not affect the SF structure. When grafted in wounds of diabetic mice, both Ad-MSCs-SF and D-Ad-MSCs-SF significantly improved tissue regeneration, reducing the wound area respectively by 40% and 35%, within three days, completing the process in around 10 days compared to 15-17 days of controls. RT2 gene profile analysis of the wounds treated with Ad-MSCs-SF and D-Ad-MSCs-SF showed an increment of genes involved in angiogenesis and matrix remodeling. Finally, Ad-MSCs-SF and D-Ad-MSCs-SF co-cultured with HUVECs, DFs and KCs, preferentially enhanced the HUVECs' migration and the release of angiogenic factors stimulating microvessel outgrowth in the aortic ring assay., Conclusions: Our results highlight for the first time that D-Ad-MSCs-SF patches are almost as effective as Ad-MSCs-SF patches in the treatment of diabetic wounds, acting through a complex mechanism that involves stimulation of angiogenesis. Our data suggest a potential use of D-Ad-MSCs-SF patches in chronic diabetic ulcers in humans.

5q14.3 deletions including the MEF2C gene have been identified to date using genomic arrays in patients with severe developmental delay or intellectual disability, stereotypic behavior, epilepsy, cerebral malformations and a facial gestalt not really distinctive though characterized by broad and/or high, bulging forehead, upslanting palpebral fissures, flat nasal root and bridge, small, upturned nose, hypotonic small mouth resulting in cupid bow/tented upper lip. MEF2C mutations have been also identified in patients with overlapping phenotype so that it is considered the gene responsible for the 5q14.3 deletion syndrome. To date, one single duplication including MEF2C has been reported in a patient with intellectual disability but its clinical significance remains uncertain also because of the large size of the imbalance. Here we present two further patients with 5q14.3 duplications including MEF2C. Their phenotype indeed suggest the pathogenic effect of the MEF2C duplication although other duplicated genes also brain expressed might contribute to the clinical features. In none of them a clear-cut syndrome can be identified. A comparison between MEF2C deleted/mutated and duplicated patients is also presented., (Copyright © 2013 Elsevier Masson SAS. All rights reserved.)

Autoinflammatory diseases are rare illnesses characterized by apparently unprovoked inflammation without high-titer auto-antibodies or antigen-specific T cells. They may cause neurological manifestations, such as meningitis and hearing loss, but they are also characterized by non-neurological manifestations. In this work we studied a 30-year-old man who had a chronic disease characterized by meningitis, progressive hearing loss, persistently raised inflammatory markers and diffuse leukoencephalopathy on brain MRI. He also suffered from chronic recurrent osteomyelitis of the mandible. The hypothesis of an autoinflammatory disease prompted us to test for the presence of mutations in interleukin-1-pathway genes and to investigate the function of this pathway in the mononuclear cells obtained from the patient. Search for mutations in genes associated with interleukin-1-pathway demonstrated a novel NLRP3 (CIAS1) mutation (p.I288M) and a previously described MEFV mutation (p.R761H), but their combination was found to be non-pathogenic. On the other hand, we uncovered a selective interleukin-6 hypersecretion within the central nervous system as the likely pathogenic mechanism. This is also supported by the response to the anti-interleukin-6-receptor monoclonal antibody tocilizumab, but not to the recombinant interleukin-1-receptor antagonist anakinra. Exome sequencing failed to identify mutations in other genes known to be involved in autoinflammatory diseases. We propose that the disease described in this patient might be a prototype of a novel category of autoinflammatory diseases characterized by prominent neurological involvement.

WE COMPARED CHROMOSOME NUMBER (CN) VARIATION AMONG VASCULAR FLORAS OF THREE DIFFERENT COUNTRIES WITH INCREASING LATITUDE IN THE BOREAL HEMISPHERE: Italy, Slovakia, Poland. Aim of the study was to verify whether the patterns of CN variation parallel the differences in latitudinal ranges. The three datasets comprised 3426 (Italy), 3493 (Slovakia) and 1870 (Poland) distinct cytotypes. Standard statistics (ANOVA, Kruskal-Wallis tests) evidenced significant differences among the three countries, mean CN increasing together with latitude. On the contrary, an inverse relation (r = -1) was evidenced among the frequency of odd CNs and latitude. Our results show that the hypothesis of a polyploid increase proportional with distance from the Equator seems to be confirmed, when territories from the same hemisphere are compared.

The Italian endemic vascular flora is composed of 1,286 specific and subspecific taxa. From the critical analysis of "Chrobase.it", 711 of them (about 55%) have been studied from a karyological point of view. These taxa belong to 52 out of 56 families and 204 out of 284 genera. These data suggest that endemic species are more studied than the flora as a whole. Mean chromosome number for Italian endemics is 2n = 30.68 ± 20.27 (median: 2n = 26, mode: 2n = 18). These values are very close to those known for the whole flora. Similar variation ranges, among endemics and species with wider distribution, are likely to reflect similar evolutionary trends. Known chromosome numbers in Italian endemics range from 2n = 8 to 2n = 182. About 9% of taxa show more than one cytotype and the frequency of Bs in the Italian endemic vascular flora is 3.3%. These values are slightly smaller compared with the whole Italian flora. Finally, for the basic chromosome numbers x = 7, 8, 9, the proportion of diploids (2n = 2x) to even polyploids (2n = 4x, 6x, 8x and 10x) can be described by the exponential function f(p) = e((5.539 - 0.637p)) (R(2) = 0.984).

Background and Aims: We compared chromosome number (CN) variation in the nearly antipodean Italian and New Zealand floras to verify (i) whether patterns of variation reflect their similar latitudinal ranges or their different biogeographic/taxonomic contexts, (ii) if any differences are equally distributed across major taxa/lineages and (iii) if the frequency, number and taxonomic distribution of B-chromosomes differ between the two countries., Methodology: We compared two datasets comprising 3426 (Italy) and 2525 (New Zealand) distinct cytotypes. We also compared a subset based on taxonomic orders and superimposed them onto a phylogeny of vascular plants. We used standard statistics, histograms, and either analysis of variance or Kruskal-Wallis tests to analyse the data., Principal Results: Mean CN of the vascular New Zealand flora is about twice that of Italy. For most orders, mean CN values for New Zealand are higher than those of the Italian flora and the differences are statistically significant. Further differences in CN variation among the orders and main clades that we studied, irrespective of geographical distinctions, are revealed. No correlation was found between chromosome and B-chromosome number., Conclusions: Mean CN of the whole New Zealand dataset is about twice that of the Italian flora. This suggests that extensive polyploidization played a major role in the evolution of the New Zealand vascular flora that is characterized by a rate of high endemism. Our results show that the hypothesis of a polyploid increase proportional to distance from the Equator cannot be applied to territories with the same latitudinal ranges but placed in different hemispheres. We suggest that bioclimatic gradients, rather than or in addition to latitudinal gradients, might account for a polyploidy increase. Our data also suggest that any adaptive role of B-chromosomes at geographic scale may be sought in their frequency rather than in their number.