102 research outputs found
Ecological Interactions of the Sexually Deceptive Orchid Orchis Galilaea
Plant species dependent on highly specific interactions with pollinators are vulnerable to environmental change. Conservation strategies therefore require a detailed understanding of pollination ecology. This two-year study examined the interactions between the sexually deceptive
orchid, Orchis galilaea, and its pollinator Lasioglossum marginatum. Relationships were investigated across three different habitats known to support O. galilaea (garrigue, oak woodland, and mixed oak/pine woodland) in Lebanon. Visitation rates to flowers were extremely low and restricted to male bees. The reproductive success of O. galilaea under ambient conditions was 29.3% (±2.4), compared to 89.0% (±2.1) in plants receiving cross-pollination by hand. No difference in reproductive success was found between habitat types, but values of reproductive success were positively correlated to the abundance of male bees. Pollination limitation can have negative impacts on the population growth of orchids, and this study provides clear evidence for more holistic approaches to habitat conservation to support specific interactions
Clinical characteristics of Polish patients with ANCA-associated vasculitides-retrospective analysis of POLVAS registry
Objective Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitides (AAV) are rare small to medium-size
vessel systemic diseases. As their clinical picture, organ involvement, and factors influencing outcome may differ
between countries and geographical areas, we decided to describe a large cohort of Polish AAV patients coming from
several referral centers-members of the Scientific Consortium of the Polish Vasculitis Registry (POLVAS).
Methods We conducted a systematic multicenter retrospective study of adult patients diagnosed with AAV between
Jan 1990 and Dec 2016 to analyze their clinical picture, organ involvement, and factors influencing outcome. Patients
were enrolled to the study by nine centers (14 clinical wards) from seven Voivodeships populated by 22.3 mln inhabitants (58.2% of the Polish population).
Results Participating centers included 625 AAV patients into the registry. Their distribution was as follows: 417 patients
(66.7%) with GPA, 106 (17.0%) with MPA, and 102 (16.3%) with EGPA. Male-to-female ratios were almost 1:1 for
GPA (210/207) and MPA (54/52), but EGPA was twice more frequent among women (34/68). Clinical manifestations
and organ involvement were analyzed by clinical phenotype. Their clinical manifestations seem very similar to other
European countries, but interestingly, men with GPA appeared to follow a more severe course than the women. Fifty five
patients died. In GPA, two variables were significantly associated with death: permanent renal replacement therapy
(PRRT) and respiratory involvement (univariate analysis). In multivariate analysis, PRRT (OR = 5.3; 95% confidence interval (CI) = 2.3–12.2), respiratory involvement (OR = 3.2; 95% CI = 1.06–9.7), and, in addition, age > 65 (OR = 2.6;
95% CI = 1.05–6.6) were independently associated with death. In MPA, also three variables were observed to be
independent predictors of death: PRRT (OR = 5.7; 95% CI = 1.3–25.5), skin involvement (OR = 4.4; 95% CI = 1.02–
19.6), and age > 65 (OR = 6.3; 95% CI = 1.18–33.7).
Conclusions In this first multicenter retrospective study of the Polish AAV patients, we have shown that their demographic
characteristics, disease manifestations, and predictors of fatal outcome follow the same pattern as those from other European
countries, with men possibly suffering from more severe course of the disease
Minority cytotypes in European populations of the Gymnadenia conopsea complex (Orchidaceae) greatly increase intraspecific and intrapopulation diversity
Background and Aims Patterns of ploidy variation among and within populations can provide valuable insights into the evolutionary mechanisms shaping the dynamics of plant systems showing ploidy diversity. Whereas data on majority ploidies are, by definition, often sufficiently extensive, much less is known about the incidence and evolutionary role of minority cytotypes. Methods Ploidy and proportions of endoreplicated genome were determined using DAPI (4',6-diamidino-2-phenylindole) flow cytometry in 6150 Gymnadenia plants (fragrant orchids) collected from 141 populations in 17 European countries. All widely recognized European species, and several taxa of less certain taxonomic status were sampled within Gymnadenia conopsea sensu lato. Key Results Most Gymnadenia populations were taxonomically and/or ploidy heterogeneous. Two majority (2x and 4x) and three minority (3x, 5x and 6x) cytotypes were identified. Evolution largely proceeded at the diploid level, whereas tetraploids were much more geographically and taxonomically restricted. Although minority ploidies constituted <2 % of the individuals sampled, they were found in 35 % of populations across the entire area investigated. The amount of nuclear DNA, together with the level of progressively partial endoreplication, separated all Gymnadenia species currently widely recognized in Europe. Conclusions Despite their low frequency, minority cytotypes substantially increase intraspecific and intrapopulation ploidy diversity estimates for fragrant orchids. The cytogenetic structure of Gymnadenia populations is remarkably dynamic and shaped by multiple evolutionary mechanisms, including both the ongoing production of unreduced gametes and heteroploid hybridization. Overall, it is likely that the level of ploidy heterogeneity experienced by most plant species/populations is currently underestimated; intensive sampling is necessary to obtain a holistic pictur
Factors associated with quality of life in systemic sclerosis: a cross-sectional study
© 2019, The Author(s). Introduction: Systemic sclerosis (SSc) is a connective tissue disease characterized by progressive fibrosis of the skin and internal organs, leading to their failure and disturbances in the morphology and function of blood vessels. The disease affects people in different ways, and identifying how the difficulties and limitations are related to quality of life may contribute to designing helpful interventions. The aim of this study was to identify factors associated with quality of life in people with SSc. Methods: This was a cross-sectional study conducted in 11 rheumatic centres in Poland. Patients diagnosed with SSc were included. Quality of life was measured using the SSc Quality of Life Questionnaire (SScQoL). The following candidate factors were entered in preliminary multivariable analysis: age, place of residence, marital status, occupational status, disease type, disease duration, pain, fatigue, intestinal problems, breathing problems, Raynaud’s symptoms, finger ulcerations, disease severity, functional disability, anxiety and depression. Factors that achieved statistical significance at the 10% level were then entered into a final multivariable model. Factors achieving statistical significance at the 5% level in the final model were considered to be associated with quality of life in SSc. Results: In total, 231 participants were included. Mean age (SD) was 55.82 (12.55) years, disease duration 8.39 (8.18) years and 198 (85.7%) were women. Factors associated with quality of life in SSc were functional disability (β = 2.854, p < 0.001) and anxiety (β = 0.404, p < 0.001). This model with two factors (functional disability and anxiety) explained 56.7% of the variance in patients with diffuse SSc and 73.2% in those with localized SSc. Conclusions: Functional disability and anxiety are significantly associated with quality of life in SSc. Interventions aimed at improving either of these factors may contribute towards improving the quality of life of people with SSc
Recovery of dialysis patients with COVID-19 : health outcomes 3 months after diagnosis in ERACODA
Background. Coronavirus disease 2019 (COVID-19)-related short-term mortality is high in dialysis patients, but longer-term outcomes are largely unknown. We therefore assessed patient recovery in a large cohort of dialysis patients 3 months after their COVID-19 diagnosis. Methods. We analyzed data on dialysis patients diagnosed with COVID-19 from 1 February 2020 to 31 March 2021 from the European Renal Association COVID-19 Database (ERACODA). The outcomes studied were patient survival, residence and functional and mental health status (estimated by their treating physician) 3 months after COVID-19 diagnosis. Complete follow-up data were available for 854 surviving patients. Patient characteristics associated with recovery were analyzed using logistic regression. Results. In 2449 hemodialysis patients (mean ± SD age 67.5 ± 14.4 years, 62% male), survival probabilities at 3 months after COVID-19 diagnosis were 90% for nonhospitalized patients (n = 1087), 73% for patients admitted to the hospital but not to an intensive care unit (ICU) (n = 1165) and 40% for those admitted to an ICU (n = 197). Patient survival hardly decreased between 28 days and 3 months after COVID-19 diagnosis. At 3 months, 87% functioned at their pre-existent functional and 94% at their pre-existent mental level. Only few of the surviving patients were still admitted to the hospital (0.8-6.3%) or a nursing home (∼5%). A higher age and frailty score at presentation and ICU admission were associated with worse functional outcome. Conclusions. Mortality between 28 days and 3 months after COVID-19 diagnosis was low and the majority of patients who survived COVID-19 recovered to their pre-existent functional and mental health level at 3 months after diagnosis
Demographic responses of boreal-montane orchid Malaxis monophyllos (L.) Sw. populations to contrasting environmental conditions
In an age of changes in species’ geographical ranges, compounded by climatic and
anthropogenic impacts, it become important to know which processes and factors
influence plant populations and their persistence in the long term.
Here we investigated dynamic and fitness components in twelve populations of
Malaxis monophyllos (L.) Sw., situated in different geographical (regions) and ecological
(type of habitat) units. Although M. monophyllos is a rare species, characterized
by highly fragmented, boreal-montane distribution range, in last few decades
it successfully colonized secondary habitats in Polish uplands. Our results indicate
that M. monophyllos is represented mainly by small populations, which annual spatial
and temporal changes might be very high, what affects the ephemeral character
of these populations, regardless of the region and type of habitat. This dynamic
structure, in turn, is caused by intensive exchange of individuals in populations, as
well as by their short above-ground life span. Despite the large range of variation
in size and reproductive traits, we can distinguish some regional patterns, which
indicate boreal region as the most optimal for M. monophyllos growth and persistence
in the long term, and with montane and upland/anthropogenic populations,
due to lower reproductive parameters, as the most threatened. Although it should
be considered that anthropogenic populations, despite their lower reproductive
parameters and instability in the long term, present an intermediate, geographical
and ecological character, therefore they may be valuable in shaping, both M.
monophyllos’ future range, as well as its potential for response on ongoing and
future changes. In general, reproduction is the main factor differentiating of M.
monophyllos populations in regions, and we can suspect that it may become the
cause of the future differentiation and isolation of these populations, occurring
with progressive range fragmentation
ВОЗМОЖНОСТИ РЕПРОДУКТИВНЫХ СИСТЕМ У ТРЕХ ВИДОВ РОДА EPIPACTIS
Возможности репродукции Epipactis helleborine, E. palustris и E. atrorubens были изучены в ходе пятилетних исследований с использованием экспериментов по искусственному опылению, наблюдения за поведением опылителей и анализа морфологии цветков от фазы их полного раскрытия до увядания. Установлено, что все изученные виды способны образовывать плоды в результате самоопыления, однако в природе спонтанное самоопыление происходит только у E. palustris, что обусловлено структурой цветка, а также продолжительной жизнеспособностью пыльцы и восприимчивостью рыльца вплоть до стадии завядания цветка. Однако у данного вида ведущим способом самоопыления является перенос пыльцы при помощи насекомых даже в пределах одного цветка. E. helleborine, E. palustris и E. atrorubens являются факультативно-автогамными видами, способными также к перекрестному опылению, что подтверждается высоким естественным плодообразованием
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