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1.
New Phytol ; 242(3): 1000-1017, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38433329

RESUMEN

Drought affects the complex interactions between Norway spruce, the bark beetle Ips typographus and associated microorganisms. We investigated the interplay of tree water status, defense and carbohydrate reserves with the incidence of bark beetle attack and infection of associated fungi in mature spruce trees. We installed roofs to induce a 2-yr moderate drought in a managed spruce stand to examine a maximum of 10 roof and 10 control trees for resin flow (RF), predawn twig water potentials, terpene, phenolic and carbohydrate bark concentrations, and bark beetle borings in field bioassays before and after inoculation with Endoconidiophora polonica and Grosmannia penicillata. Drought-stressed trees showed more attacks and significantly longer fungal lesions than controls, but maintained terpene resin defenses at predrought levels. Reduced RF and lower mono- and diterpene, but not phenolic concentrations were linked with increased host selection. Bark beetle attack and fungi stimulated chemical defenses, yet G. penicillata reduced phenolic and carbohydrate contents. Chemical defenses did not decrease under mild, prolonged drought in our simulated small-scale biotic infestations. However, during natural mass attacks, reductions in carbon fixation under drought, in combination with fungal consumption of carbohydrates, may deplete tree defenses and facilitate colonization by I. typographus.


Asunto(s)
Escarabajos , Picea , Gorgojos , Animales , Sequías , Picea/microbiología , Corteza de la Planta/química , Enfermedades de las Plantas/microbiología , Terpenos , Fenoles , Noruega , Agua/análisis , Carbohidratos/análisis
2.
Arch Gynecol Obstet ; 310(5): 2647-2655, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-38705889

RESUMEN

PURPOSE: Endometriosis and infertility are associated with impaired partnership and sexuality of the patients, but also of their male partners. Also, endometriosis is one of the most common causes of infertility, resulting in a large overlap of both pathologies. The aim of this study was to determine the association of different predictors of partnership and sexual satisfaction and dyadic effects in couples with endometriosis and infertility. METHODS: A cross-sectional study was conducted with n = 62 women with endometriosis and n = 46 partners, including a total of n = 44 couples, some of whom were affected by infertility. The questionnaire included items on partnership, sexuality, depression, social support, and desire for a child. Multiple linear regression and the actor-partner-interdependence-model were used for analysis. RESULTS: Significant dyadic effects only occurred in couples with both endometriosis and infertility. Depression showed a significant negative actor effect in men for partnership satisfaction and a negative actor and partner effect in women for sexuality satisfaction (p < .05). For women, social support showed a significant positive actor effect for partnership satisfaction (p < .05), age showed a significant actor and partner effect for sexuality satisfaction (p < .05). CONCLUSION: The results show a significant association of endometriosis and infertility with partnership and sexuality satisfaction. Infertility could be a decisive factor. However, the large overlapping of both endometriosis und infertility in many couples support the importance of further studies to differentiate between the both effects. TRIAL REGISTRATION: German Clinical Trials Register DRKS00014362 on the 29.03.2018.


Asunto(s)
Endometriosis , Satisfacción Personal , Apoyo Social , Humanos , Endometriosis/psicología , Endometriosis/complicaciones , Femenino , Masculino , Estudios Transversales , Adulto , Encuestas y Cuestionarios , Infertilidad Femenina/psicología , Infertilidad Femenina/etiología , Depresión/psicología , Depresión/etiología , Parejas Sexuales/psicología , Relaciones Interpersonales , Infertilidad/psicología
3.
Arch Gynecol Obstet ; 308(3): 1007-1014, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37347283

RESUMEN

PURPOSE: For many couples, bearing children is a common life goal; however it cannot always be fulfilled. Undergoing infertility treatment does not always guarantee pregnancies and live births. Couples experience miscarriages and even discontinue infertility treatment. Significant medical predictors for the outcome of infertility treatment have yet to be fully identified. METHODS: To further our understanding, a cross-sectional 5-year follow-up survey was undertaken, in which 95 women and 82 men that have been treated at the Women's Hospital of Heidelberg University participated. Binary logistic regressions, parametric and non-parametric methods were used for our sample to determine the relevance of biological (infertility diagnoses, maternal and paternal age) and lifestyle factors (smoking, drinking, over- and underweight) on the outcome of infertility treatment (clinical pregnancy, live birth, miscarriage, dropout rate). In addition, chi-square tests were used to examine differences in the outcome depending on the number of risk factors being present. RESULTS: In the binary logistic regression models for clinical pregnancies, live births and drop outs were statistically significant only for the maternal age, whereas the maternal and paternal BMI, smoking, infertility diagnoses and infections showed no significant predicting effect on any of the outcome variables. A correlation between the number of risk factors and the outcome of infertility treatment could not be excluded. CONCLUSION: The results confirm that maternal age has an effect on infertility treatment, whereas the relevance of other possible medical predictors remains unclear. Further large-scale studies should be considered to increase our knowledge on their predictive power.


Asunto(s)
Aborto Espontáneo , Infertilidad , Embarazo , Masculino , Niño , Humanos , Femenino , Estudios Transversales , Estudios de Seguimiento , Infertilidad/terapia , Edad Materna , Nacimiento Vivo/epidemiología , Aborto Espontáneo/epidemiología , Técnicas Reproductivas Asistidas , Resultado del Tratamiento
4.
Health Qual Life Outcomes ; 20(1): 86, 2022 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-35643578

RESUMEN

BACKGROUND: Endometriosis is often associated with severe dysmenorrhea, pelvic pain and dyspareunia and has a high impact on daily life as well as sexuality. Quality of partnership positively influences the course of various diseases and ability to cope with emotional and physical distress. However, studies focusing on the male partners of endometriosis patients are rare, and even less is known about the reciprocal relationship in these couples. Therefore, this study aims to explore the interrelations in couples with endometriosis in matters of psychological distress, sexual and partnership satisfaction and social support. METHODS: The cross-sectional study was conducted in two university-affiliated fertility centres in Germany and Austria with n = 104 female/male couples affected by endometriosis. Participants completed a questionnaire regarding endometriosis, partnership, sexuality, stress, anxiety, depression and social support. Both women and men were asked about the impact of women's endometriosis-related pain (IEP) on their everyday life (e.g. leisure time). Data were analysed using the Actor-Partner-Interdependence Model. RESULTS: Significant partner effects were evident: High depression, anxiety and stress scores in women were associated with a higher IEP in men (all p ≤ 0.01), reciprocally high stress and depression scores in men were correlated with a higher IEP in women (all p ≤ 0.05). Less sexual satisfaction in women was associated with a higher IEP in men (p = 0.040). There was a significant reciprocal association between the perceived lack of understanding from the social environment and a higher IEP, for both women (p = 0.022) and men (p = 0.027). CONCLUSIONS: The male partner should be taken into account when counselling or treating women with endometriosis. Our study shows a high interdependence and reciprocal influence from both partners-positively and negatively-concerning psychological distress and sexual satisfaction. Furthermore, there ought to be more awareness for the psychosocial impact of endometriosis, especially in regard to social support and understanding. Talking about and improving sexual satisfaction as well as enhancing stress reducing techniques may hold great benefits for dealing with endometriosis. Registration number The study is registered with the German Clinical Trials Register (DRKS), number DRKS00014362.


Asunto(s)
Endometriosis , Estudios Transversales , Endometriosis/complicaciones , Femenino , Humanos , Masculino , Satisfacción Personal , Calidad de Vida/psicología , Conducta Sexual/psicología
5.
Physiol Plant ; 173(4): 2181-2190, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34549436

RESUMEN

Plant stress experiments are commonly performed with plants grown in containers to better control environmental conditions. Nevertheless, the container can constrain plant growth and development, and this confounding effect is generally ignored, particularly in studies on woody species. Here, we evaluate the effect of the container volume in drought experiments using grapevine as a model plant. Grapevines grown in small (7 L, S) or large (20 L, L) containers were subjected to drought stress and rewatering treatments. We monitored plant stomatal conductance (gs ), midday stem water potential (Ψs ), and photosynthetic rate (AN ) throughout the experiment. The effect of the container volume on the stem and petiole xylem anatomy, as well as on the total leaf area (LA), was assessed before drought imposition. The results showed that LA did not differ between plants in L or S containers, but S vines exhibited a higher theoretical hydraulic conductance at the petiole level. Under drought L and S similarly reduced gs and AN , but plants in S containers reached lower Ψs than those in L. Nevertheless, upon rewatering droughted plants in S containers exhibited a faster stomata re-opening than those in L, probably as a consequence of the differences in the stress degree experienced and the biochemical adjustment at the leaf level. Therefore, a suitable experimental design should consider the container volume used in relation to the desired traits to be studied for unbiased results.


Asunto(s)
Deshidratación , Sequías , Hojas de la Planta , Estomas de Plantas , Agua , Xilema
6.
Trees (Berl West) ; 35(5): 1467-1484, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34720435

RESUMEN

KEY MESSAGE: Hybrid saplings were more reactive to soil water deficit than Japanese and European larch. European larch had hydraulically safer wood and anisohydric behavior, Japanese and hybrid larch showed isohydric strategy. ABSTRACT: Deciduous larch species could be an alternative to evergreen conifers in reforestation, but little is known about drought sensitivity of their saplings. The effect of an experimental drought on hydraulics and quantitative wood anatomy was tested on saplings of European larch (EL, Larix decidua), Japanese larch (JL, Larix kaempferi) and their hybrid (HL). Across species, biomass, transpiration rate and relative water content were higher in controls than in drought stressed trees, but transpiration efficiency was lower. JL had the highest transpiration efficiency under drought, and EL the lowest, coinciding with slower growth of EL. Wood of EL formed before drought was hydraulically safer as shown by higher wall/lumen ratio and lower pit cavity area. EL neither had a significant increase in transpiration efficiency nor a reduction in transpiration rate under drought, suggesting that the stomata remained open under soil water deficit. HL saplings were the most reactive to water shortage, indicated by intra-annual density fluctuations and a decrease in relative water content of the sapwood. Significant reduction in transpiration by HL suggested a higher stomatal sensitivity, while the same leaf surface area was maintained and radial growth was still similar to its best parent, the JL. The latter showed a significantly lower leaf surface area under drought than controls. EL, with its hydraulically safer wood, followed an anisohydric behavior, while JL and HL revealed an isohydric strategy. Altogether, our results suggest species dependent acclimations to drought stress, whereby HL followed the strategy of JL rather than that of EL. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s00468-021-02129-4.

7.
Molecules ; 26(14)2021 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-34299657

RESUMEN

Papyri belong to the oldest writing grounds in history. Their conservation is of the highest importance in preserving our cultural heritage, which is best achieved based on an extensive knowledge of the materials' constituents to choose a tailored conservation approach. Thermogravimetric Analysis (TGA) has been widely employed to quantify cellulose and lignin in papyrus sheets, yielding reported lignin contents of 25% to 40%. In this work, the TGA method conventionally used for papyrus samples was repeated and compared to other lignin determination approaches (Klason-lignin and acetyl bromide-soluble lignin). TGA can lead to a large overestimation of the lignin content of commercial papyrus sheets (~27%) compared to the other methods (~5%). A similar overestimation of the lignin content was found for the pith and rind of the native papyrus plant. We concluded that the TGA method should, therefore, not be used for lignin quantification.


Asunto(s)
Lignina/análisis , Extractos Vegetales
8.
Eur J Haematol ; 105(6): 722-730, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32658347

RESUMEN

OBJECTIVES: Major complications affecting the central nervous system (CNS) present a challenge after allogeneic stem cell transplantation (allo-SCT). METHODS: Incidence, risk factors, and outcome were retrospectively analyzed in 888 patients in a monocentric study. RESULTS: Cumulative incidence (CI) of major CNS complications at 1 year was 14.8% (95%CI 12.3%-17.2%). Median follow-up is 11 months. CNS complications were documented in 132 patients: in 36 cases, classified metabolic; 26, drug-related neurotoxicity (14 attributed to cyclosporine A, 4 to antilymphocyte globulin); 11, cerebrovascular (ischemic n = 8, bleeding n = 3); 9, infections; 9, psychiatric; and 9, malignant. The cause of CNS symptoms remained unclear for 37 patients (28%). Multivariate analysis demonstrated an association of CNS complication with patient age (P < .001). The estimated OS of patients with any CNS complication was significantly lower than in patients without neurological complications (P < .001), and the CI of non-relapse mortality (NRM) was higher for patients with CNS complication (P < .001). A significant negative impact on survival can only be demonstrated for metabolic CNS complications and CNS infections (NRM, P < .0001 and P = .0003, respectively), and relapse (P < .0001). CONCLUSION: CNS complications after allo-SCT are frequent events with a major contribution to morbidity and mortality. In particular, the situations of unclear neurological complications need to be clarified by intensive research.


Asunto(s)
Enfermedades del Sistema Nervioso Central/epidemiología , Enfermedades del Sistema Nervioso Central/etiología , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Adulto , Enfermedades del Sistema Nervioso Central/diagnóstico , Susceptibilidad a Enfermedades , Femenino , Trasplante de Células Madre Hematopoyéticas/métodos , Trasplante de Células Madre Hematopoyéticas/estadística & datos numéricos , Humanos , Incidencia , Masculino , Morbilidad , Mortalidad , Pronóstico , Recurrencia , Estudios Retrospectivos , Factores de Riesgo , Trasplante Homólogo
9.
Ann Bot ; 125(5): 701-720, 2020 04 25.
Artículo en Inglés | MEDLINE | ID: mdl-31420666

RESUMEN

BACKGROUND: In trees, secondary metabolites (SMs) are essential for determining the effectiveness of defence systems against fungi and why defences are sometimes breached. Using the CODIT model (Compartmentalization of Damage/Dysfunction in Trees), we explain defence processes at the cellular level. CODIT is a highly compartmented defence system that relies on the signalling, synthesis and transport of defence compounds through a three-dimensional lattice of parenchyma against the spread of decay fungi in xylem. SCOPE: The model conceptualizes 'walls' that are pre-formed, formed during and formed after wounding events. For sapwood, SMs range in molecular size, which directly affects performance and the response times in which they can be produced. When triggered, high-molecular weight SMs such as suberin and lignin are synthesized slowly (phytoalexins), but can also be in place at the time of wounding (phytoanticipins). In contrast, low-molecular weight phenolic compounds such as flavonoids can be manufactured de novo (phytoalexins) rapidly in response to fungal colonization. De novo production of SMs can be regulated in response to fungal pathogenicity levels. The protective nature of heartwood is partly based on the level of accumulated antimicrobial SMs (phytoanticipins) during the transitionary stage into a normally dead substance. Effectiveness against fungal colonization in heartwood is largely determined by the genetics of the host. CONCLUSION: Here we review recent advances in our understanding of the role of SMs in trees in the context of CODIT, with emphasis on the relationship between defence, carbohydrate availability and the hydraulic system.We also raise the limitations of the CODIT model and suggest its modification, encompassing other defence theory concepts. We envisage the development of a new defence system that is modular based and incorporates all components (and organs) of the tree from micro- to macro-scales.


Asunto(s)
Árboles , Xilema , Hongos , Lignina
10.
Physiol Plant ; 165(4): 843-854, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29923608

RESUMEN

More frequently occurring, drought waves call for a deeper understanding of tree hydraulics and fast and easily applicable methods to measure drought stress. The aim of this study was to establish empirical relationships between the percent loss of hydraulic conductivity (PLC) and the relative water loss (RWL) in woody stem axes with different P50 , i.e. the water potential (Ψ) that causes 50% conductivity loss. Branches and saplings of temperate conifer (Picea abies, Larix decidua) and angiosperm species (Acer campestre, Fagus sylvatica, Populus x canescens, Populus tremula, Sorbus torminalis) and trunk wood of mature P. abies trees were analyzed. P50 was calculated from hydraulic measurements following bench top dehydration or air injection. RWL and PLC were fitted by linear, quadratic or cubic equations. Species- or age-specific RWLs at P50 varied between 10 and 25% and P88 , the Ψ that causes 88% conductivity loss, between 18 and 44%. P50 was predicted from the relationship between Ψ and the RWL. The predictive quality for P50 across species was almost 1:1 (r2 = 0.99). The approach presented allows thus reliable and fast prediction of PLC from RWL. Branches and saplings with high hydraulic vulnerability tended to have lower RWLs at P50 and at P88 . The results are discussed with regard to the different water storage capacities in sapwood and survival strategies under drought stress. Potential applications are screening trees for drought sensitivity and a fast interpretation of diurnal, seasonal or drought induced changes in xylem water content upon their impact on conductivity loss.


Asunto(s)
Árboles/metabolismo , Árboles/fisiología , Agua/metabolismo , Sequías , Magnoliopsida/metabolismo , Magnoliopsida/fisiología , Tallos de la Planta/metabolismo , Tallos de la Planta/fisiología , Tracheophyta/metabolismo , Tracheophyta/fisiología
11.
New Phytol ; 213(1): 170-180, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-27533709

RESUMEN

Wood structure differs widely among tree species and species with faster growth, higher mortality and larger maximum size have been reported to have fewer but larger vessels and higher hydraulic conductivity (Kh). However, previous studies compiled data from various sources, often failed to control tree size and rarely controlled variation in other traits. We measured wood density, tree size and vessel traits for 325 species from a wet forest in Panama, and compared wood and leaf traits to demographic traits using species-level data and phylogenetically independent contrasts. Wood traits showed strong phylogenetic signal whereas pairwise relationships between traits were mostly phylogenetically independent. Trees with larger vessels had a lower fraction of the cross-sectional area occupied by vessel lumina, suggesting that the hydraulic efficiency of large vessels permits trees to dedicate a larger proportion of the wood to functions other than water transport. Vessel traits were more strongly correlated with the size of individual trees than with maximal size of a species. When individual tree size was included in models, Kh scaled positively with maximal size and was the best predictor for both diameter and biomass growth rates, but was unrelated to mortality.


Asunto(s)
Carácter Cuantitativo Heredable , Bosque Lluvioso , Árboles/crecimiento & desarrollo , Madera/fisiología , Panamá , Filogenia , Análisis de Componente Principal , Análisis de Regresión , Especificidad de la Especie , Árboles/anatomía & histología
13.
Health Qual Life Outcomes ; 14: 27, 2016 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-26911144

RESUMEN

BACKGROUND: Only a few studies have reported cross-cultural comparisons regarding psychosocial consequences of infertility. Differences between societies with different cultural backgrounds were revealed and seemed to be based on the importance of pronatalism. Our aim was to measure cross-cultural differences in fertility specific quality of life of infertile couples in Germany, Hungary and Jordan who attend a fertility center in a cross-sectional study. METHODS: A cross-sectional study was conducted in one fertility clinic in Germany, in five fertility clinics in Hungary and in one fertility clinic in Jordan. Overall 750 couples (252 couples in Jordan, 246 couples in Germany and 252 couples in Hungary) attending the first medical infertility consultation were asked to fill out our questionnaire set. Fertility specific quality of life (FertiQoL) and sociodemographic differences were measured between couples from three countries. RESULTS: Jordanian couples had the shortest relationship (5.8 ± 4.3 yrs.), though they reported the longest duration of child wish (4.2 ± 3.6 yrs.) and fertility treatments (3.0 ± 3.3 yrs.). The proportion of high education was considerably higher in Jordanian women and men (60 % and 66 %, respectively) compared to the other two samples. First, marked cross-country differences were obtained on Emotional, Mind/Body and Relational subscales of the FertiQoL, indicating that Jordanian couples reported poorer fertility-related quality of life than Germans and Hungarians (p < 0.001). After controlling for the sociodemographic and medical variables, a significant difference only in the Emotional domain was observed (p < 0.001). CONCLUSIONS: The study revealed only a few cultural based differences in fertility specific quality of life between the couples of the three countries. Thus, infertility counselors should pay attention to psychosocial problems rooted in individual sociocultural aspects of the infertile couple regardless of cultural stereotypes. Further studies should identify sociocultural factors within different subgroups of infertile patients instead of focusing different societies as a whole because intra-cultural psychosocial differences in experiencing infertility seem to be more important for the individual patient than intercultural differences.


Asunto(s)
Fertilidad , Infertilidad/epidemiología , Calidad de Vida/psicología , Adulto , Comparación Transcultural , Estudios Transversales , Emociones , Femenino , Alemania , Humanos , Hungría , Jordania , Masculino , Matrimonio/estadística & datos numéricos , Encuestas y Cuestionarios
14.
New Phytol ; 208(2): 625-32, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26010417

RESUMEN

Acoustic emission (AE) analysis allows nondestructive monitoring of embolism formation in plant xylem, but signal interpretation and agreement of acoustically measured hydraulic vulnerability with reference hydraulic techniques remain under debate. We compared the hydraulic vulnerability of 16 species and three crop tree cultivars using hydraulic flow measurements and acoustic emission monitoring, proposing the use of time-dependent AE rates as a novel parameter for AE analysis. There was a linear correlation between the water potential (Ψ) at 50% loss of hydraulic conductivity (P50 ) and the Ψ at maximum AE activity (Pmaxrate ), where species with lower P50 also had lower Pmaxrate (P < 0.001, R(2)  = 0.76). Using AE rates instead of cumulative counts for AE analysis allows more efficient estimation of P50 , while excluding problematic AE at late stages of dehydration.


Asunto(s)
Acústica , Xilema/fisiología , Factores de Tiempo , Agua
15.
New Phytol ; 205(3): 1128-1141, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25417785

RESUMEN

Drought is considered to enhance susceptibility of Norway spruce (Picea abies) to infestations by the Eurasian spruce bark beetle (Ips typographus, Coleoptera: Curculionidae), although empirical evidence is scarce. We studied the impact of experimentally induced drought on tree water status and constitutive resin flow, and how physiological stress affects host acceptance and resistance. We established rain-out shelters to induce both severe (two full-cover plots) and moderate (two semi-cover plots) drought stress. In total, 18 sample trees, which were divided equally between the above treatment plots and two control plots, were investigated. Infestation was controlled experimentally using a novel 'attack box' method. Treatments influenced the ratios of successful and defended attacks, but predisposition of trees to infestation appeared to be mainly driven by variations in stress status of the individual trees over time. With increasingly negative twig water potentials and decreasing resin exudation, the defence capability of the spruce trees decreased. We provide empirical evidence that water-limiting conditions impair Norway spruce resistance to bark beetle attack. Yet, at the same time our data point to reduced host acceptance by I. typographus with more extreme drought stress, indicated by strongly negative pre-dawn twig water potentials.


Asunto(s)
Escarabajos/fisiología , Picea/parasitología , Corteza de la Planta/parasitología , Enfermedades de las Plantas/parasitología , Agua/metabolismo , Animales , Austria , Clima , Susceptibilidad a Enfermedades , Sequías , Modelos Lineales , Suelo , Estrés Fisiológico , Árboles/parasitología , Agua/análisis , Tiempo (Meteorología)
16.
Plant Physiol ; 164(4): 1731-40, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24521876

RESUMEN

Xylem embolism is a limiting factor for woody species worldwide. Conifers at the alpine timberline are exposed to drought and freeze-thaw stress during winter, which induce potentially lethal embolism. Previous studies indicated that timberline trees survive by xylem refilling. In this study on Picea abies, refilling was monitored during winter and spring seasons and analyzed in the laboratory and in situ experiments, based on hydraulic, anatomical, and histochemical methods. Refilling started in late winter, when the soil was frozen and soil water not available for the trees. Xylem embolism caused up to 86.2% ± 3.1% loss of conductivity and was correlated with the ratio of closed pits. Refilling of xylem as well as recovery in shoot conductance started in February and corresponded with starch accumulation in secondary phloem and in the mesophyll of needles, where we also observed increasing aquaporin densities in the phloem and endodermis. This indicates that active, cellular processes play a role for refilling even under winter conditions. As demonstrated by our experiments, water for refilling was thereby taken up via the branches, likely by foliar water uptake. Our results suggest that refilling is based on water shifts to embolized tracheids via intact xylem, phloem, and parenchyma, whereby aquaporins reduce resistances along the symplastic pathway and aspirated pits facilitate isolation of refilling tracheids. Refilling must be taken into account as a key process in plant hydraulics and in estimating future effects of climate change on forests and alpine tree ecosystems.


Asunto(s)
Picea/fisiología , Estaciones del Año , Agua/metabolismo , Xilema/fisiología , Transporte Biológico , Picea/citología , Brotes de la Planta/fisiología , Tallos de la Planta/fisiología , Xilema/citología
17.
Front Plant Sci ; 15: 1414448, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38988629

RESUMEN

Introduction: Drought-induced embolism formation in conifers is associated with several tracheid and pit traits, which vary in parallel from stem apex to base. We tested whether this axial anatomical variability is associated with a progressive variation in embolism vulnerability along the stem from apex to base. Methods: We assessed the tracheid hydraulic diameter (Dh), mean pit membrane area (PMA) and the xylem pressure at 50% loss of conductivity (P50) on longitudinal stem segments extracted at different distances from the stem apex (DFA) in a Picea abies and an Abies alba tree. Results: In both trees, Dh and PMA scaled with DFA 0.2. P50 varied for more than 3 MPa from the treetop to the stem base, according to a scaling of -P50 with DFA-0.2 . The largest Dh, PMA and P50 variation occurred for DFA<1.5 m. PMA and Dh scaled more than isometrically (exponent b=1.2). Pit traits vary proportionally with tracheid lumen diameter. Discussion and conclusions: Apex-to-base trends in tracheid and pit traits, along with variations in P50, suggest a strong structure-function relationship that is influenced by DFA. Although the effect of DFA on P50 has not been extensively explored previously, we propose that analyzing the relationship between P50 and DFA could be crucial for a comprehensive assessment of embolism vulnerability at the individual level.

18.
J Clin Med ; 13(20)2024 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-39458146

RESUMEN

Background: Hereditary transthyretin-related amyloidosis is a clinically heterogeneous autosomal dominant disease caused by pathogenic variants in the TTR gene (hATTR amyloidosis). Objective: The current study describes the demographic, clinical, and genetic characteristics of patients with suspected hATTR amyloidosis. Methods: This study is part of the "Hereditary transthyretin-related amyloidosis and longitudinal monitoring of TTR-positive patients" (TRAMmoniTTR) study. This study included 3167 participants, along with their clinical details. Principal component (PC) analysis was used to analyze their clinical symptomatology. Next-generation sequencing of the TTR gene was performed and genotype-phenotype relationships were investigated. We compared the demographic and clinical characteristics using the principal components (PCs) and also compared participants with and without the TTR pathogenic variants. Results: We identified five main clinical phenotypes out of 22 single symptoms that explained 49% of the variation. The first two PCs referred to polyneuropathy and cardiomyopathy. We found significant differences between gender and PC-polyneuropathy and PC-cardiomyopathy, with male over-representation in the higher quantiles of PC-polyneuropathy and male under-representation in the lowest quantiles of PC-cardiomyopathy. We identified 92 participants with hATTR (3%), exhibiting 17 unique heterozygous TTR variants. The p.Val50Met variant was the most frequent. Furthermore, 503 participants (20%) were identified with ATTR and no relevant TTR variants (ATTRwt). We detected significant differences between the ATTRwt and hATTR groups, with male gender predominance in only the ATTRwt group and a positive family history of polyneuropathy and/or cardiomyopathy among the hATTR participants. Conclusions: The current clinical and genetic characterization of this cohort serves as a foundation for further longitudinal monitoring and assessment.

19.
Geburtshilfe Frauenheilkd ; 83(7): 843-849, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37404978

RESUMEN

Introduction For some patients, undergoing medical treatment for infertility is a cause of major emotional stress which the couple needs to deal with together; it can be said that infertility is a shared stressor. From the literature it is known that a subjectively perceived sense of self-efficacy supports the patient's ability to cope adaptively with an illness. As the basis for this study, we assumed that high levels of self-efficacy are associated with low psychological risk scores (e.g., for anxiety or depressiveness), both in the patient themselves and in their partner. Accordingly, in infertility patients, targeted support to promote helpful self-efficacy expectations could represent a new counselling strategy that could enable psychologically vulnerable patients to better cope with the treatment procedure and treatment failures of medically assisted reproduction, making these patients less at risk with regard to psychosocial factors. Methods 721 women and men attending five fertility centers in Germany (Heidelberg, Berlin), Austria (Innsbruck), and Switzerland (St. Gallen, Basel) completed the SCREENIVF-R questionnaire to identify psychological risk factors for amplified emotional problems, as well as the ISE scale to measure self-efficacy. Using paired t-tests and the actor-partner interdependence model, we analyzed the data of 320 couples. Results Considering the study participants as couples, women had a higher risk score than men for four out of five risk factors (depressiveness, anxiety, lack of acceptance, helplessness). In all of the risk areas, it was possible to identify a protective effect from self-efficacy on the patient's own risk factors (actor effect). There was a negative correlation between the men's self-efficacy level and the women's feelings of depressiveness and helplessness (partner effect, man → woman). The women's self-efficacy levels had a positive correlation with acceptance and access to social support in the men (partner effect, woman → man). Conclusion Because infertility is generally something that a couple has to deal with together, future studies should focus on couples as the unit of analysis instead of just analyzing the men and women separately. In addition, couples therapy should be the gold standard in psychotherapy for infertility patients.

20.
Diagnostics (Basel) ; 13(17)2023 08 30.
Artículo en Inglés | MEDLINE | ID: mdl-37685353

RESUMEN

Gaucher disease (GD) is a rare autosomal recessive disorder arising from bi-allelic variants in the GBA1 gene, encoding glucocerebrosidase. Deficiency of this enzyme leads to progressive accumulation of the sphingolipid glucosylsphingosine (lyso-Gb1). The international, multicenter, observational "Lyso-Gb1 as a Long-term Prognostic Biomarker in Gaucher Disease"-LYSO-PROOF study succeeded in enrolling a cohort of 160 treatment-naïve GD patients from diverse geographic regions and evaluated the potential of lyso-Gb1 as a specific biomarker for GD. Using genotypes based on established classifications for clinical presentation, patients were stratified into type 1 GD (n = 114) and further subdivided into mild (n = 66) and severe type 1 GD (n = 48). Due to having previously unreported genotypes, 46 patients could not be classified. Though lyso-Gb1 values at enrollment were widely distributed, they displayed a moderate and statistically highly significant correlation with disease severity measured by the GD-DS3 scoring system in all GD patients (r = 0.602, p < 0.0001). These findings support the utility of lyso-Gb1 as a sensitive biomarker for GD and indicate that it could help to predict the clinical course of patients with undescribed genotypes to improve personalized care in the future.

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