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1.
J Clin Med ; 12(15)2023 Jul 29.
Article in English | MEDLINE | ID: mdl-37568403

ABSTRACT

Molecular study has become an invaluable tool in the field of RASopathies. Treatment with recombinant human growth hormone is approved in Noonan syndrome but not in the other RASopathies. The aim of this study was to learn about the molecular base of a large cohort of patients with RASopathies, with particular emphasis on patients with pathogenic variants in genes other than PTPN11, and its potential impact on rGH treatment indication. We reviewed the clinical diagnosis and molecular findings in 451 patients with a genetically confirmed RASopathy. HRAS alterations were detected in only 2 out of 19 patients referred with a Costello syndrome suspicion, whereas pathogenic variants in RAF1 and SHOC2 were detected in 3 and 2, respectively. In 22 patients referred with a generic suspicion of RASopathy, including cardiofaciocutaneous syndrome, pathogenic alterations in classic Noonan syndrome genes (PTPN11, SOS1, RAF1, LZTR1, and RIT1) were found in 7 patients and pathogenic variants in genes associated with other RASopathies (HRAS, SHOC2, and PPPCB1) in 4. The correct nosological classification of patients with RASopathies is critical to decide whether they are candidates for treatment with rhGH. Our data illustrate the complexity of differential diagnosis in RASopathies, as well as the importance of genetic testing to guide the diagnostic orientation in these patients.

2.
Sci Total Environ ; 892: 164552, 2023 Sep 20.
Article in English | MEDLINE | ID: mdl-37279808

ABSTRACT

Land use change and nutrient pollution are two pervasive stressors that can modify carbon cycling, as they influence the inputs and the transformation of detritus. Understanding their impact on stream food webs and on diversity is particularly pressing, as streams are largely fuelled by detrital material received from the adjacent riparian environment. Here we assess how a switch from native deciduous forest to Eucalyptus plantations and nutrient enrichment alter the size distribution of stream detritivore communities and decomposition rates of detritus. As expected, more detritus resulted in higher size-independent, or overall, abundance (i.e. higher intercept of size spectra). This change in overall abundance was mainly driven by a change of the relative contribution of large taxa (Amphipoda and Trichoptera), which changed from an average relative abundance of 55.5 to 77.2 % between the sites compared for resource quantity differences in our study. In contrast, detritus quality modified the relative abundance of large vs small individuals (i.e. size spectra slopes), with shallow slopes of size spectra (proportionately more large individuals) associated with sites with nutrient-richer waters and steeper slopes (proportionately fewer large individuals) associated with sites draining Eucalyptus plantations. Decomposition rates of alder leaves due to macroinvertebrates increased from 0.0003 to 0.0142 when relative contribution of large organisms increased (modelled slopes of size spectra: -1.00 and - 0.33, respectively), highlighting the importance of large sized individuals for ecosystem functioning. Our study reveals that land use change and nutrient pollution can greatly impair the transfer of energy through the detrital or 'brown' food web by means of intra- and inter-specific responses to quality and quantity of the detritus. These responses enable linking land use change and nutrient pollution to ecosystem productivity and carbon cycling.


Subject(s)
Ecosystem , Eucalyptus , Humans , Food Chain , Forests , Rivers/chemistry , Carbon
3.
Microb Ecol ; 85(3): 839-852, 2023 Apr.
Article in English | MEDLINE | ID: mdl-35654854

ABSTRACT

Ongoing global warming is expected to alter temperature-dependent processes. Nevertheless, how co-occurring local drivers will influence temperature sensitivity of plant litter decomposition in lotic ecosystems remains uncertain. Here, we examined the temperature sensitivity of microbial-mediated decomposition, microbial respiration, fungal biomass and leaf nutrients of two plant species varying in litter quality. We also assessed whether the type of microbial community and stream water characteristics influence such responses to temperature. We incubated alder (Alnus glutinosa) and eucalypt (Eucalyptus globulus) litter discs in three streams differing in autumn-winter water temperature (range 4.6-8.9 °C). Simultaneously, in laboratory microcosms, litter discs microbially conditioned in these streams were incubated at 5, 10 and 15 °C with water from the conditioning stream and with a water control from an additional stream. Both in the field and in the laboratory, higher temperatures enhanced litter decomposition rates, except for eucalypt in the field. Leaf quality modified the response of decomposition to temperature in the field, with eucalypt leaf litter showing a lower increase, whereas it did not in the laboratory. The origin of microbial community only affected the decomposition rates in the laboratory, but it did not modify the response to temperature. Water quality only defined the phosphorus content of the leaf litter or the fungal biomass, but it did not modify the response to temperature. Our results suggest that the acceleration in decomposition by global warming will be shaped by local factors, mainly by leaf litter quality, in headwater streams.


Subject(s)
Alnus , Ecosystem , Temperature , Biomass , Plant Leaves/microbiology , Alnus/microbiology , Fresh Water
4.
J Clin Endocrinol Metab ; 107(10): 2912-2924, 2022 09 28.
Article in English | MEDLINE | ID: mdl-35902207

ABSTRACT

CONTEXT: Pappalysins (PAPP-A, PAPP-A2) modulate body growth by increasing insulin-like growth factor I (IGF-I) bioavailability through cleavage of insulin-like growth factor binding proteins (IGFBPs) and are inhibited by stanniocalcins (STC1, STC2). Normative data on these novel factors, as well as on free IGF-I and uncleaved fractions of IGFBPs, are not well established. OBJECTIVE: This work aimed to determine serum concentrations of PAPP-A, PAPP-A2, STC1, and STC2 in relationship with other growth hormone (GH)-IGF axis parameters during development. METHODS: Full-term newborns (150; gestational age: 39.30 ±â€…1.10 weeks), 40 preterm newborns (30.87 ±â€…3.35 weeks), and 1071 healthy individuals (aged 1-30 years) were included in the study and divided according to their Tanner stages (males and females): I:163 males, 154 females; II:100 males, 75 females; III:83 males, 96 females; IV: 77 males, 86 females; and V:109 males,128 females. RESULTS: Serum concentrations of PAPP-A, PAPP-A2, STC1, STC2, IGFBP-2, total IGFBP-4, and total IGFBP-5 were elevated at birth and declined throughout childhood. In postnatal life, PAPP-A2 concentrations decreased progressively in concomitance with the free/total IGF-I ratio; however, stanniocalcin concentrations remained stable. PAPP-A2 concentrations positively correlated with the free/total IGF-I ratio (r = +0.28; P < .001) and negatively with the intact/total IGFBP-3 ratio (r = -0.23; P < .001). PAPP-A concentrations inversely correlated with intact/total IGFBP-4 ratio (r = -0.21; P < .001), with PAPP-A concentrations being lower in females at all ages. Association studies indicate the importance of stanniocalcins and pappalysins in the control of this axis in an age-specific manner. CONCLUSION: This study provides reference values of pappalysins and stanniocalcins, which modulate IGF-I activity by changing the concentrations of cleaved and uncleaved IGFBPs.


Subject(s)
Insulin-Like Growth Factor Binding Protein 4 , Insulin-Like Growth Factor I , Child , Female , Glycoproteins , Growth Hormone/metabolism , Humans , Infant , Infant, Newborn , Insulin-Like Growth Factor Binding Protein 2 , Insulin-Like Growth Factor Binding Protein 3 , Insulin-Like Growth Factor Binding Protein 4/metabolism , Insulin-Like Growth Factor Binding Protein 5 , Insulin-Like Growth Factor Binding Proteins , Insulin-Like Growth Factor I/metabolism , Male , Pregnancy-Associated Plasma Protein-A/metabolism
5.
Dermatol Ther ; 35(5): e15371, 2022 05.
Article in English | MEDLINE | ID: mdl-35141996

ABSTRACT

Goltz syndrome is an X-linked dominant, multisystem birth defect due to PORCN mutation. The skin findings follow Blaschko's lines and often show epidermal atrophy and herniation of subcutaneous fatty tissue. Regarding treatment, light sources can offer a good therapeutic option for some manifestations of this rare disease and improve the aesthetic appearance of the skin lesions. We report two new cases of Goltz syndrome in which the cutaneous findings remarkably improved with pulsed dye laser and carbon dioxide laser.


Subject(s)
Focal Dermal Hypoplasia , Laser Therapy , Acyltransferases/genetics , Focal Dermal Hypoplasia/diagnosis , Focal Dermal Hypoplasia/genetics , Focal Dermal Hypoplasia/pathology , Humans , Membrane Proteins/genetics , Mutation
7.
Cells ; 10(12)2021 12 18.
Article in English | MEDLINE | ID: mdl-34944082

ABSTRACT

The growth hormone (GH)/insulin-like growth factor (IGF) axis plays fundamental roles during development, maturation, and aging. Members of this axis, composed of various ligands, receptors, and binding proteins, are regulated in a tissue- and time-specific manner that requires precise control that is not completely understood. Some of the most recent advances in understanding the implications of this axis in human growth are derived from the identifications of new mutations in the gene encoding the pregnancy-associated plasma protein PAPP-A2 protease that liberates IGFs from their carrier proteins in a selective manner to allow binding to the IGF receptor 1. The identification of three nonrelated families with mutations in the PAPP-A2 gene has shed light on how this protease affects human physiology. This review summarizes our understanding of the implications of PAPP-A2 in growth physiology, obtained from studies in genetically modified animal models and the PAPP-A2 deficient patients known to date.


Subject(s)
Disease , Physiological Phenomena , Pregnancy-Associated Plasma Protein-A/metabolism , Animals , Disease Models, Animal , Growth Hormone/metabolism , Humans , Insulin-Like Growth Factor I/metabolism , Mutation/genetics , Pregnancy-Associated Plasma Protein-A/genetics
8.
Growth Horm IGF Res ; 60-61: 101419, 2021.
Article in English | MEDLINE | ID: mdl-34358737

ABSTRACT

PAPP-A2 deficiency is a novel syndrome characterized by short stature due to low IGF bioactivity, skeletal abnormalities and decreased bone mineral density (BMD). Treatment with recombinant human IGF-1 (rhIGF-1) for 1 year demonstrated to increase growth velocity and BMD, without reported adverse effects, but data regarding the long-term efficacy and safety of rhIGF-1 administration in this entity has not yet been reported. Two Spanish siblings with short stature due to a homozygous loss-of-function mutation in the PAPP-A2 gene (p.D643fs25*) were treated with rhIGF-1 twice daily for six years. Growth velocity continued to increase and both patients achieved their target height. Free IGF-1 concentrations increased notably after rhIGF-1 administration, with serum IGFBP-3, IGFBP-5 and ALS levels also being higher during treatment. BMD was progressively normalized and an increase in lean mass was also noted during treatment. No episodes of hypoglycemia or any other adverse effects were documented. An increase in the growth of kidney and spleen length was observed in one of the patients.


Subject(s)
Body Height , Growth Disorders/drug therapy , Human Growth Hormone/administration & dosage , Insulin-Like Growth Factor Binding Protein 3/metabolism , Insulin-Like Growth Factor I/metabolism , Pregnancy-Associated Plasma Protein-A/deficiency , Recombinant Proteins/administration & dosage , Child , Female , Follow-Up Studies , Growth Disorders/genetics , Growth Disorders/metabolism , Growth Disorders/pathology , Humans , Male , Pregnancy-Associated Plasma Protein-A/genetics , Prognosis
9.
Sci Rep ; 10(1): 19682, 2020 11 12.
Article in English | MEDLINE | ID: mdl-33184346

ABSTRACT

Plant litter decomposition is a key ecosystem process that can be altered by global changes such as biodiversity loss. These effects can be particularly important in detritus-based ecosystems, such as headwater streams, which are mainly fuelled by allochthonous plant litter inputs. However, experiments examining effects of plant diversity on litter decomposition in streams have not reached consensus about which measures of biodiversity are more relevant. We explored the influence of two of these measures, plant species richness (SR; monocultures vs. 3-species mixtures) and phylogenetic distance (PD; species belonging to the same family vs. different families), on leaf litter decomposition and associated processes and variables (nutrient dynamics, fungal biomass and detritivore growth), in a stream microcosm experiment using litter from 9 tree species belonging to 3 families. We found a negative effect of SR on decomposition (which contradicted the results of previous experiments) but a positive effect on fungal biomass. While PD did not affect decomposition, both SR and PD altered nutrient dynamics: there was greater litter and detritivore N loss in low-PD mixtures, and greater litter P loss and detritivore P gain in monocultures. This suggested that the number of species in mixtures and the similarity of their traits both modulated nutrient availability and utilization by detritivores. Moreover, the greater fungal biomass with higher SR could imply positive effects on detritivores in the longer term. Our results provide new insights of the functional repercussions of biodiversity loss by going beyond the often-explored relationship between SR and decomposition, and reveal an influence of plant species phylogenetic relatedness on nutrient cycling that merits further investigation.


Subject(s)
Biodegradation, Environmental , Biodiversity , Plant Physiological Phenomena , Plants/genetics , Ecosystem , Plants/classification , Rivers , Trees/physiology
11.
J Dtsch Dermatol Ges ; 17(9): 923-931, 2019 Sep.
Article in English | MEDLINE | ID: mdl-31487109

ABSTRACT

BACKGROUND AND OBJECTIVES: In recent years, the hypothesis that increasing the empowerment of patients can help to improve health outcomes and rationalize the use of health services has become relevant, especially for chronic diseases. Developing validated measurement tools is necessary to achieve this goal. In the field of dermatology, there are few studies related to empowerment of the patient. The aim of the present research is to develop and validate a self-administered questionnaire for adult patients diagnosed with atopic dermatitis (AD) in order to measure their level of empowerment. METHODS: After a literature review and the establishment of consulting groups of patients and dermatologists, a large battery of 35 items was generated, based on the dimensions included in previous empowerment descriptions. A multidisciplinary group selected the 20 most suitable items to include in the questionnaire. A cross-sectional study was carried out with the items included in the questionnaire as well as demographic and clinical characteristics. To reduce the number of items and measure the construct validity, an exploratory factorial analysis (EFA) of the primary components and varimax rotation were used. Cronbach's α was used to measure the reliability of the individual scales and the global questionnaire. RESULTS: 242 valid questionnaires were included. After completion of the EFA, the final Dermatitis Atópica EMPoderamiento (DATEMP) questionnaire was composed of 17 items that converged on four factors. The four scales had adequate reliability: "Knowledge" (Cronbach's alpha = 0.808), "Abilities" (Cronbach's alpha = 0.744), "Intention to change" (Cronbach's alpha = 0.798) and "Coping skills" (Cronbach's alpha = 0.772). The overall Cronbach's α of the questionnaire was 0.764. CONCLUSIONS: The DATEMP questionnaire is the first specific empowerment measurement instrument developed for patients with AD that has demonstrated adequate levels of reliability and construct validity. It is a self-administered questionnaire that is simple and quick to answer.


Subject(s)
Dermatitis, Atopic/psychology , Empowerment , Surveys and Questionnaires/standards , Adaptation, Psychological , Adolescent , Adult , Aged , Cross-Sectional Studies , Female , Health Knowledge, Attitudes, Practice , Humans , Male , Middle Aged , Pilot Projects , Sample Size , Young Adult
12.
Ecology ; 100(12): e02847, 2019 12.
Article in English | MEDLINE | ID: mdl-31351003

ABSTRACT

Biodiversity loss is occurring globally at unprecedented rates, altering the functioning of the Earth's ecosystems. Multiple processes are often key components of ecosystem functioning, but it is unclear how biodiversity loss affects ecosystem multifunctionality (i.e., the ability of ecosystems to maintain multiple processes simultaneously). This is particularly true for some ecosystem types such as streams, which have been understudied, despite their key role in global biogeochemical cycles and their serious impairment by the widespread loss of riparian vegetation as a result of global change. Using a microcosm experiment, we tested whether losing riparian plant diversity affected stream multifunctionality, taking into account nine key processes related to litter decomposition, animal biomass production, and nutrient cycling, and simulating plant species loss from four to one in the presence or absence of litter-feeding detritivores. Multifunctionality increased with plant diversity in the presence of detritivores and decreased in their absence, evidencing a key role of detritivores in biodiversity-ecosystem-functioning (BEF) relationships. Moreover, by exploring effects of plant diversity on each process individually we were able to reveal potential mechanisms underlying BEF relationships; for example, effects of plant diversity on nutrient cycling occurred at least partly via indirect nutrient transfer, and were possibly accompanied by changes in microbial stoichiometry. Such mechanisms were unnoticeable when examining multifunctionality metrics, suggesting that individual processes provide crucial information to understand how stream ecosystem functioning is impaired by biodiversity loss.


Subject(s)
Ecosystem , Rivers , Animals , Biodiversity , Plant Leaves , Plants
13.
J Sports Sci Med ; 18(2): 344-350, 2019 06.
Article in English | MEDLINE | ID: mdl-31191105

ABSTRACT

This study aimed to assess the effects of flywheel resistance exercise training on postural stability and mobility in older adults and to investigate whether changes in power are related to improvements in balance. Thirty-six participants were randomly allocated to either a flywheel resistance exercise training group (ETG; n = 18) who underwent 6-weeks of training (2 to 3 days per week) or a control group (CON; n = 18). The average power and Mean Propulsive Velocity (MPV) were computed. Timed up-and-go test (TUG) and postural balance (anterior-posterior (AP) and medial-lateral (ML) center of pressure (COP) excursions) in different tasks were also assessed. Within-group analyses showed a significantly better performance in mobility (TUG, p < 0.01) and COPAP with open eyes (p < 0.05) for ETG. Between-groups analyses showed significant improvements in TUG (-0.68 [-1.25 to -0.98]) and in COPAP (-2.90 [-4.82 to -0.99]) in ETG compared with CON. Mean power also increased in ETG and the changes were related to those observed in stability (COP; r = -0.378, p < 0.05). In conclusion flywheel resistance exercise training improved balance and mobility in older adults as well as muscle power.


Subject(s)
Postural Balance , Resistance Training/methods , Aged , Exercise Test , Female , Humans , Male , Middle Aged , Resistance Training/instrumentation
14.
Sci Total Environ ; 661: 306-315, 2019 Apr 15.
Article in English | MEDLINE | ID: mdl-30677678

ABSTRACT

Global patterns of biodiversity have emerged for soil microorganisms, plants and animals, and the extraordinary significance of microbial functions in ecosystems is also well established. Virtually unknown, however, are large-scale patterns of microbial diversity in freshwaters, although these aquatic ecosystems are hotspots of biodiversity and biogeochemical processes. Here we report on the first large-scale study of biodiversity of leaf-litter fungi in streams along a latitudinal gradient unravelled by Illumina sequencing. The study is based on fungal communities colonizing standardized plant litter in 19 globally distributed stream locations between 69°N and 44°S. Fungal richness suggests a hump-shaped distribution along the latitudinal gradient. Strikingly, community composition of fungi was more clearly related to thermal preferences than to biogeography. Our results suggest that identifying differences in key environmental drivers, such as temperature, among taxa and ecosystem types is critical to unravel the global patterns of aquatic fungal diversity.


Subject(s)
Fungi , Microbiota , Rivers/microbiology , Plant Leaves/microbiology , Spatial Analysis
15.
J Anim Ecol ; 87(5): 1465-1474, 2018 09.
Article in English | MEDLINE | ID: mdl-29928758

ABSTRACT

Understanding how biodiversity loss influences plant litter decomposition-that is, the biologically mediated conversion of coarse to fine particulate organic matter-is crucial to predict changes in the functioning of many stream ecosystems, where detrital food webs are dominant. Rates of litter decomposition are influenced by detritivore diversity, but the mechanisms behind this relationship are uncertain. As differences in detritivore body size are a major determinant of interspecific interactions, they should be key for predicting effects of detritivore diversity on decomposition. To explore this question, we manipulated detritivore diversity and body size simultaneously in a microcosm experiment using two small (Leuctra geniculata and Lepidostoma hirtum) and two large detritivore species (Sericostoma pyrenaicum and Echinogammarus berilloni) in all possible 1-, 2- and 4-species combinations, and litter discs of Alnus glutinosa. We expected that larger species would facilitate smaller species through the production of smaller litter fragments, resulting in faster decomposition and greater growth of smaller species in polycultures containing species of different body size. To examine this hypothesis, we used a set of "diversity-interaction" models that explored how decomposition was affected by different interspecific interactions and the role of body size, and quantified the magnitude of such effect through ratios of decomposition rates and detritivore growth between polycultures and monocultures. We found a clear positive effect of detritivore diversity on decomposition, which was mainly explained by facilitation and niche partitioning. Facilitation of small animals by larger ones was evidenced by a 12% increase in decomposition rates in polycultures compared to monocultures and the higher growth (20%) of small species, which partly fed on fine particulate organic matter produced by larger animals. When the large species were together in polycultures, decomposition was enhanced by 19%, but there were no changes in growth; niche partitioning was a plausible mechanism behind the increase in decomposition rates, as both species fed on different parts of litter discs, only one species being able to eat less palatable parts. Our study demonstrates that interspecific differences in body size should be taken into account in diversity-decomposition studies. Future studies should also consider differences in species' vulnerability to extinction depending on body size and how this might affect ecosystem functioning in different scenarios of detritivore diversity and more complex food webs.


Subject(s)
Ecosystem , Plant Leaves , Animals , Biodiversity , Food Chain , Rivers
16.
J Pediatr Endocrinol Metab ; 31(7): 743-750, 2018 Jul 26.
Article in English | MEDLINE | ID: mdl-29953411

ABSTRACT

Background The approach to the clinical management of Graves' disease (GD) is debatable. This study aimed to identify predictors of remission in pediatric GD. Methods A longitudinal study of 36 children and adolescents with GD followed from 1997 to 2017 at a single tertiary hospital was performed. Clinical and biochemical parameters, including comorbidities, treatment with anti-thyroid drugs (ATD) or definitive therapy (radioiodine [RIT] and thyroidectomy), and remission as the main outcome were collected. We performed a multivariable logistic regression analysis to identify likely predictors of remission. Results Among patients, most were female, in late puberty, with exuberant symptoms at onset. Eleven also suffered from Down syndrome (DS). Thirty-four patients (94%) started on methimazole from disease onset, and 25 (69%) received it as the only therapy, with a mean duration of 2.7±1.8 years. Six changed to RIT and three underwent thyroidectomy; no DS patient received definitive therapy. Remission was higher in DS patients (45% vs. 25%, p=0.24), but afterwards (3.9±2.5 vs. 2.3±1.4 years, p<0.05); there was no significance in relapsing (20% vs. 15%). Females were less likely to reach remission (p<0.05); serum free thyroxine at onset was higher (p<0.05) in patients who required definitive therapy. Thyroid-stimulating immunoglobulin (TSI) values normalized in exclusively ATD therapy, especially from 2 years on (p<0.05). Conclusions Males were more likely to achieve remission. TSI values may normalize in GD, notably from the second year of treatment. DS children may benefit with conservative management in GD.


Subject(s)
Antithyroid Agents/therapeutic use , Down Syndrome/complications , Hyperthyroidism/drug therapy , Case-Control Studies , Child , Disease Management , Female , Follow-Up Studies , Humans , Hyperthyroidism/etiology , Longitudinal Studies , Male , Prognosis , Remission Induction , Retrospective Studies
17.
Rev. esp. patol ; 51(2): 128-133, abr.-jun. 2018. ilus
Article in Spanish | IBECS | ID: ibc-171789

ABSTRACT

Paciente varón de 30 años que consultó por una lesión en el 5.° dedo del pie derecho con afectación cutánea del pulpejo y de todo el borde externo. Macroscópicamente se trataba de una lesión violácea con superficie queratósica de 1cm. En la radiografía simple se objetivó un aumento de partes blandas, de posible origen vascular. La resonancia mostró una lesión que erosionaba la cortical de la falange distal, de señal muy hiperintensa compatible con malformación vascular de bajo flujo. Se realizó extirpación de la lesión mediante amputación de la falange distal y a nivel histológico se observó una lesión formada por vasos de tipo venoso y tipo linfático que eran D2-40 positivos. En las malformaciones vasculares la participación cutánea, aunque sea mínima, puede esconder una importante afectación profunda. Cuando asientan sobre planos óseos hay que descartar la erosión de la cortical del hueso subyacente (AU)


A 30 year old male presented with a cutaneous lesion on the distal area of the 5th toe with involvement of the outer edges. Macroscopically, it was a 1cm violaceous and keratotic lesion. Radiography showed an increase in soft tissue, possibly due to a vascular lesion. MRI showed a hyper-intense signal with erosion of the distal phalanx compatible with a low-flow vascular malformation. The distal phalanx was amputated. Histopathology revealed a lesion formed by venous and D2-40 positive lymphatic vessels. This case highlights the fact that even minimal skin involvement in vascular malformations may conceal an important deeper lesion, such as erosion of the cortical bone (AU)


Subject(s)
Humans , Male , Adult , Vascular Malformations/pathology , Toes/abnormalities , Lymphatic Vessels/abnormalities , Vascular Malformations/surgery , Antibodies, Monoclonal/analysis , Bone and Bones/pathology
18.
PLoS One ; 13(5): e0198243, 2018.
Article in English | MEDLINE | ID: mdl-29813129

ABSTRACT

Biodiversity loss in riparian forests has the potential to alter rates of leaf litter decomposition in stream ecosystems. However, studies have reported the full range of positive, negative and no effects of plant diversity loss on decomposition, and there is currently no explanation for such inconsistent results. Furthermore, it is uncertain whether plant diversity loss affects other ecological processes related to decomposition, such as fine particulate organic matter production or detritivore growth, which precludes a thorough understanding of how detrital stream food webs are impacted by plant diversity loss. We used a microcosm experiment to examine the effects of plant diversity loss on litter decomposition, fine particulate organic matter production, and growth of a dominant leaf-shredding detritivore, using litter mixtures varying in species composition. We hypothesized that plant diversity loss would decrease the rates of all studied processes, but such effects would depend on the leaf traits present in litter mixtures (both their average values and their variability). Our findings partly supported our hypotheses, showing that plant diversity loss had a consistently negative effect on litter decomposition and fine particulate organic matter production (but not on detritivore growth) across litter mixtures, which was mediated by detritivores. Importantly, the magnitude of the diversity effect and the relative importance of different mechanisms underlying this effect (i.e., complementarity vs. selection) varied depending on the species composition of litter mixtures, mainly because of differences in litter nutritional quality and trait variability. Complementarity was prevalent but varied in size, with positive selection effects also occurring in some mixtures. Our results support the notion that loss of riparian plant species is detrimental to key stream ecosystem processes that drive detrital food webs, but that the magnitude of such effects largely depends on the the order of species loss.


Subject(s)
Biodiversity , Organic Chemicals/chemistry , Organic Chemicals/metabolism , Plant Leaves/metabolism , Rivers/chemistry
19.
Rev Esp Patol ; 51(2): 128-133, 2018.
Article in Spanish | MEDLINE | ID: mdl-29602374

ABSTRACT

A 30 year old male presented with a cutaneous lesion on the distal area of the 5th toe with involvement of the outer edges. Macroscopically, it was a 1cm violaceous and keratotic lesion. Radiography showed an increase in soft tissue, possibly due to a vascular lesion. MRI showed a hyper-intense signal with erosion of the distal phalanx compatible with a low-flow vascular malformation. The distal phalanx was amputated. Histopathology revealed a lesion formed by venous and D2-40 positive lymphatic vessels. This case highlights the fact that even minimal skin involvement in vascular malformations may conceal an important deeper lesion, such as erosion of the cortical bone.


Subject(s)
Abnormalities, Multiple , Bone Diseases/etiology , Lymphatic Vessels/abnormalities , Vascular Malformations/complications , Adult , Humans , Male , Toes
20.
Microb Ecol ; 76(2): 328-339, 2018 Aug.
Article in English | MEDLINE | ID: mdl-29417187

ABSTRACT

Aquatic hyphomycetes represent a large component of the microbial assemblage that decomposes submerged leaf-litter in fluvial ecosystems. The structure and activity of these fungal decomposers depend on environmental factors. Fungal communities may adapt to local habitat conditions; however, little is known about how fungal communities respond to abrupt changes in factors such as nutrient availability and temperature. To respond to this question, we carried out a cross-transplantation experiment, which assessed the decomposer activity and structure of this microbial community on decaying leaves transplanted from a cold and oligotrophic stream (S1) to a warmer and nitrogen-richer one (S2) and vice versa. Results were compared to those from untransplanted leaves decomposing either at S1 or at S2. In terms of days, untransplanted leaves were decomposed at a similar rate in both streams; the change to warmer and nitrogen-richer waters (S1 ➔ S2) significantly enhanced the decomposition process while the reciprocal transplantation (S2 ➔ S1) did not alter decomposition rate. However, when standardizing the temperature effects by using degree-days, microbial decomposers under colder conditions were more efficient in terms of accumulated heat, independent of the initial or final incubation site. Regarding community structure, taxa richness and diversity of aquatic hyphomycetes appear to be favoured under warmer and richer conditions, increasing after transplantation to S2 but with little effect on the predominant taxa. However, the reciprocal transplantation (S2 ➔ S1) yielded a clear decline of the dominant taxa at S2 (Lunulospora curvula) in favour of the local dominant ones. Thus, effects of environmental changes on activity and community structure can be highly variable and not always clearly linked or reciprocal. Therefore, results from simplified experimental designs (e.g. artificial assemblages under laboratory conditions) must be taken with caution. Additional field studies and manipulative experimentation dealing with natural communities are required when trying to extend individual results to complex scenarios such as those projected by global change.


Subject(s)
Mitosporic Fungi/physiology , Nutrients , Rivers/microbiology , Temperature , Atlantic Ocean , Biodiversity , Canada , Ecosystem , Environmental Microbiology , Microbiota , Mitosporic Fungi/classification , Mycobiome , Nitrogen , Plant Leaves/microbiology , Rivers/chemistry
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