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1.
Hum Brain Mapp ; 45(1): e26553, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38224541

RESUMO

22q11.2 deletion syndrome (22q11DS) is the most frequently occurring microdeletion in humans. It is associated with a significant impact on brain structure, including prominent reductions in gray matter volume (GMV), and neuropsychiatric manifestations, including cognitive impairment and psychosis. It is unclear whether GMV alterations in 22q11DS occur according to distinct structural patterns. Then, 783 participants (470 with 22q11DS: 51% females, mean age [SD] 18.2 [9.2]; and 313 typically developing [TD] controls: 46% females, mean age 18.0 [8.6]) from 13 datasets were included in the present study. We segmented structural T1-weighted brain MRI scans and extracted GMV images, which were then utilized in a novel source-based morphometry (SBM) pipeline (SS-Detect) to generate structural brain patterns (SBPs) that capture co-varying GMV. We investigated the impact of the 22q11.2 deletion, deletion size, intelligence quotient, and psychosis on the SBPs. Seventeen GMV-SBPs were derived, which provided spatial patterns of GMV covariance associated with a quantitative metric (i.e., loading score) for analysis. Patterns of topographically widespread differences in GMV covariance, including the cerebellum, discriminated individuals with 22q11DS from healthy controls. The spatial extents of the SBPs that revealed disparities between individuals with 22q11DS and controls were consistent with the findings of the univariate voxel-based morphometry analysis. Larger deletion size was associated with significantly lower GMV in frontal and occipital SBPs; however, history of psychosis did not show a strong relationship with these covariance patterns. 22q11DS is associated with distinct structural abnormalities captured by topographical GMV covariance patterns that include the cerebellum. Findings indicate that structural anomalies in 22q11DS manifest in a nonrandom manner and in distinct covarying anatomical patterns, rather than a diffuse global process. These SBP abnormalities converge with previously reported cortical surface area abnormalities, suggesting disturbances of early neurodevelopment as the most likely underlying mechanism.


Assuntos
Síndrome de DiGeorge , Transtornos Psicóticos , Feminino , Humanos , Adolescente , Masculino , Síndrome de DiGeorge/diagnóstico por imagem , Imageamento por Ressonância Magnética , Encéfalo/diagnóstico por imagem , Transtornos Psicóticos/complicações , Substância Cinzenta/diagnóstico por imagem
2.
Radiology ; 309(1): e230096, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37906015

RESUMO

Background Clinically acquired brain MRI scans represent a valuable but underused resource for investigating neurodevelopment due to their technical heterogeneity and lack of appropriate controls. These barriers have curtailed retrospective studies of clinical brain MRI scans compared with more costly prospectively acquired research-quality brain MRI scans. Purpose To provide a benchmark for neuroanatomic variability in clinically acquired brain MRI scans with limited imaging pathology (SLIPs) and to evaluate if growth charts from curated clinical MRI scans differed from research-quality MRI scans or were influenced by clinical indication for the scan. Materials and Methods In this secondary analysis of preexisting data, clinical brain MRI SLIPs from an urban pediatric health care system (individuals aged ≤22 years) were scanned across nine 3.0-T MRI scanners. The curation process included manual review of signed radiology reports and automated and manual quality review of images without gross pathology. Global and regional volumetric imaging phenotypes were measured using two image segmentation pipelines, and clinical brain growth charts were quantitatively compared with charts derived from a large set of research controls in the same age range by means of Pearson correlation and age at peak volume. Results The curated clinical data set included 532 patients (277 male; median age, 10 years [IQR, 5-14 years]; age range, 28 days after birth to 22 years) scanned between 2005 and 2020. Clinical brain growth charts were highly correlated with growth charts derived from research data sets (22 studies, 8346 individuals [4947 male]; age range, 152 days after birth to 22 years) in terms of normative developmental trajectories predicted by the models (median r = 0.979). Conclusion The clinical indication of the scans did not significantly bias the output of clinical brain charts. Brain growth charts derived from clinical controls with limited imaging pathology were highly correlated with brain charts from research controls, suggesting the potential of curated clinical MRI scans to supplement research data sets. © RSNA, 2023 Supplemental material is available for this article. See also the editorial by Ertl-Wagner and Pai in this issue.


Assuntos
Encéfalo , Gráficos de Crescimento , Humanos , Masculino , Criança , Recém-Nascido , Estudos Retrospectivos , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Imageamento por Ressonância Magnética/métodos , Cabeça
3.
Arch Dermatol Res ; 315(9): 2617-2622, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37432466

RESUMO

The Harmonising Outcome Measures for Eczema (HOME) initiative established a core outcome set (COS) for atopic eczema (AE) clinical trials in 2019. This set encompasses four core outcome domains and corresponding measurement instruments: clinical signs (EASI), patient-reported symptoms (POEM and NRS 11 point for worst itch over the last 24 h), quality of life (DLQI/CDLQI/IDQoLI), and long-term control (Recap or ADCT). Following its roadmap, the HOME initiative is now focused on supporting implementation of the COS. To identify barriers and facilitators to implementation of the COS, and to guide the effort to promote COS uptake, a virtual consensus meeting was held over 2 days (September 25-26, 2021) attended by 55 participants (26 healthcare professionals, 16 methodologists, 5 patients, 4 industry representatives, and 4 students). Implementation themes were identified by a pre-meeting survey distributed to HOME members, presentations, and whole-group discussion. Participants were divided into five multi-professional small groups which ranked their top 3 most important themes, followed by whole-group discussion and anonymous consensus voting (consensus criteria: < 30% disagreement). Three most important implementation themes were identified and agreed upon: (1) awareness and stakeholder engagement, (2) universal applicability of the COS, and (3) ensuring minimum administrative burden. Working groups to address these issues are now a priority for the HOME initiative. The results from this meeting will inform the development of a HOME Implementation Roadmap in an effort to support other COS groups planning for effective implementation of their core sets.


Assuntos
Dermatite Atópica , Eczema , Humanos , Dermatite Atópica/terapia , Dermatite Atópica/diagnóstico , Avaliação de Resultados em Cuidados de Saúde , Qualidade de Vida , Projetos de Pesquisa , Índice de Gravidade de Doença , Resultado do Tratamento , Ensaios Clínicos como Assunto
5.
Phys Rev Lett ; 130(23): 232301, 2023 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-37354417

RESUMO

For the first time, the (d,^{2}He) reaction was successfully used in inverse kinematics to extract the Gamow-Teller transition strength in the ß^{+} direction from an unstable nucleus. The new technique was made possible by the use of an active-target time-projection chamber and a magnetic spectrometer, and opens a path to addressing a range of scientific challenges, including in astrophysics and neutrino physics. In this Letter, the nucleus studied was ^{14}O, and the Gamow-Teller transition strength to ^{14}N was extracted up to an excitation energy of 22 MeV. The data were compared to shell-model and state-of-the-art coupled-cluster calculations. Shell-model calculations reproduce the measured Gamow-Teller strength distribution up to about 15 MeV reasonably well, after the application of a phenomenological quenching factor. In a significant step forward to better understand this quenching, the coupled-cluster calculation reproduces the full strength distribution well without such quenching, owing to the large model space, the inclusion of strong correlations, and the coupling of the weak interaction to two nucleons through two-body currents.


Assuntos
Núcleo Celular , Física , Fenômenos Biomecânicos
6.
JAR Life ; 12: 25-34, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37351539

RESUMO

Background: Observational studies and some randomized controlled trials have suggested that nutritional supplementation could be a possible intervention pathway to prevent cognitive decline and Alzheimer's disease (AD). As measuring amyloid-ß and tau pathophysiology by positron emission tomography (PET) or cerebrospinal fluid (CSF) analyses may be perceived as complex, plasma versions of such biomarkers have emerged as more accessible alternatives with comparable capacity of predicting cognitive impairment. Objectives: This study aimed to evaluate the effect of a 1-year intervention with a nutritional blend on plasma p-tau181 and glial fibrillary acidic protein (GFAP) levels in community-dwelling older adults. Effects were further assessed in exploratory analyses within sub-cohorts stratified according to p-tau status (with the third tertile considered as high: ≥15.1 pg/ mL) and to apolipoprotein E (APOE) ε4 allele status. Methods: A total of 289 participants ≥70 years (56.4% female, mean age 78.1 years, SD=4.7) of the randomized, double-blind, multicenter, placebo-controlled Nolan trial had their plasma p-tau181 assessed, and daily took either a nutritional blend (composed of thiamin, riboflavin, niacin, pantothenic acid, pyridoxine, biotin, folic acid, cobalamin, vitamin E, vitamin C, vitamin D, choline, selenium, citrulline, eicosapentaenoic acid - EPA, and docosahexaenoic acid - DHA) or placebo for 1 year. Results: After 1-year, both groups presented a significant increase in plasma p-tau181 and GFAP values, with no effect of the intervention (p-tau181 between-group difference: 0.27pg/mL, 95%CI: -0.95, 1.48; p=0.665; GFAP between-group difference: -3.28 pg/mL, 95%CI: -17.25, 10.69; p=0.644). P-tau-and APOE ε4-stratified analyses provided similar findings. Conclusions: In community-dwelling older adults, we observed an increase in plasma p-tau181 and GFAP levels that was not different between the supplementation groups after one year.

7.
J Dairy Sci ; 106(7): 5115-5126, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37164866

RESUMO

This study aimed to determine the effect of 2 simple breeding strategies combining artificial insemination (AI) after detection of estrus (AIED) and timed AI (TAI) on first-service fertility in lactating Holstein cows. Weekly, lactating Holstein cows (n = l,049) between 40 and 46 d in milk (DIM) were randomly assigned to initiate 1 of 2 breeding strategies for first service: Presynch-14 and PG+G. Presynch-14 is a presynchronization strategy with 2 PGF2α treatments 14 d apart with the last PGF2α 14 d before the initiation of the Ovsynch protocol. Cows treated with PG+G receive a simpler presynchronization program that uses PGF2α and GnRH simultaneously 7 d before Ovsynch. In both treatments, cows detected in standing estrus by tail chalk at any time ≥55 DIM were inseminated, and treatment was discontinued (n = 525). Cows completing treatment received TAI from 78 to 84 DIM (n = 526). In a subgroup of cows that received TAI, blood was collected (n = 163) to assess circulating concentrations of progesterone, and ultrasonographic evaluations of ovaries were performed on the day of first GnRH of Ovsynch (n = 162) and PGF2α of Ovsynch (n = 122). The proportion of cows that received TAI was greater for PG+G compared with Presynch-14 (63.5 vs. 31.9%), which increased DIM at first service for cows treated with PG+G compared with Presynch-14 (75.5 ± 0.4 vs. 68.7 ± 0.4). For cows receiving TAI, the ovulatory response to first GnRH of Ovsynch (73.8 vs. 48.8%) and the proportion of cows with functional corpora lutea (92.6 vs. 73.1%) were greater for PG+G than Presynch-14. Cows treated with PG+G had greater overall pregnancy per AI (P/AI) 42 ± 7 d after AI (40.2 vs. 33.6%) and calving per AI (32.1 vs. 25.2%) than Presynch-14. For cows receiving AIED, treatment did not affect P/AI 42 ± 7 d after AI. However, for cows receiving TAI, PG+G increased P/AI compared with Presynch-14 (44.6 vs. 35.2%). Overall, cows receiving TAI had greater P/AI 42 ± 7 d after AI (42.5 vs. 31.5%) and calving per AI (34.1 vs. 23.7%) and decreased pregnancy loss (16.8 vs. 25.2%) than cows receiving AIED. In summary, PG+G increased the proportion of cows receiving TAI and the DIM at first service, P/AI, and calving per AI compared with Presynch-14 when both TAI programs were combined with AIED.


Assuntos
Hormônio Liberador de Gonadotropina , Lactação , Gravidez , Feminino , Bovinos , Animais , Sincronização do Estro/métodos , Dinoprosta/farmacologia , Estro , Progesterona , Inseminação Artificial/veterinária , Inseminação Artificial/métodos
8.
Artigo em Inglês | MEDLINE | ID: mdl-36695075

RESUMO

BACKGROUND: Research suggests that Alopecia areata (AA) and Major Depressive Disorder (MDD) show substantial comorbidity. To date, no study has investigated the hypothesis that this is attributable to shared genetic aetiology. OBJECTIVES: To investigate AA-MDD comorbidity on the epidemiological and molecular genetic levels. METHODS: First, epidemiological analyses were performed using data from a cohort of adult German health insurance beneficiaries (n = 1.855 million) to determine the population-based prevalence of AA-MDD comorbidity. Second, analyses were performed to determine the prevalence of MDD in a clinical AA case-control sample with data on psychiatric phenotypes, stratifying for demographic factors to identify possible contributing factors to AA-MDD comorbidity. Third, the genetic overlap between AA and MDD was investigated using a polygenic risk score (PRS) approach and linkage disequilibrium score (LDSC) regression. For PRS, summary statistics from a large MDD GWAS meta-analysis (PGC-MD2) were used as the training sample, while a Central European AA cohort, including the above-mentioned AA patients, and an independent replication US-AA cohort were used as target samples. LDSC was performed using summary statistics of PGC-MD2 and the largest AA meta-analysis to date. RESULTS: High levels of AA-MDD comorbidity were reported in the population-based (MDD in 24% of AA patients), and clinical samples (MDD in 44% of AA patients). MDD-PRS explained a modest proportion of variance in AA case-control status (R2  = 1%). This signal was limited to the major histocompatibility complex (MHC) region on chromosome 6. LDSC regression (excluding MHC) revealed no significant genetic correlation between AA and MDD. CONCLUSIONS: As in previous research, AA patients showed an increased prevalence of MDD. The present analyses suggest that genetic overlap may be confined to the MHC region, which is implicated in immune function. More detailed investigation is required to refine understanding of how the MHC is involved in the development of AA and MDD comorbidity.

9.
Artigo em Inglês | MEDLINE | ID: mdl-34848384

RESUMO

BACKGROUND: The presence of a 22q11.2 microdeletion (22q11.2 deletion syndrome [22q11DS]) ranks among the greatest known genetic risk factors for the development of psychotic disorders. There is emerging evidence that the cerebellum is important in the pathophysiology of psychosis. However, there is currently limited information on cerebellar neuroanatomy in 22q11DS specifically. METHODS: High-resolution 3T magnetic resonance imaging was acquired in 79 individuals with 22q11DS and 70 typically developing control subjects (N = 149). Lobar and lobule-level cerebellar volumes were estimated using validated automated segmentation algorithms, and subsequently group differences were compared. Hierarchical clustering, principal component analysis, and graph theoretical models were used to explore intercerebellar relationships. Cerebrocerebellar structural connectivity with cortical thickness was examined via linear regression models. RESULTS: Individuals with 22q11DS had, on average, 17.3% smaller total cerebellar volumes relative to typically developing subjects (p < .0001). The lobules of the superior posterior cerebellum (e.g., VII and VIII) were particularly affected in 22q11DS. However, all cerebellar lobules were significantly smaller, even after adjusting for total brain volumes (all cerebellar lobules p < .0002). The superior posterior lobule was disproportionately associated with cortical thickness in the frontal lobes and cingulate cortex, brain regions known be affected in 22q11DS. Exploratory analyses suggested that the superior posterior lobule, particularly Crus I, may be associated with psychotic symptoms in 22q11DS. CONCLUSIONS: The cerebellum is a critical but understudied component of the 22q11DS neuroendophenotype.


Assuntos
Síndrome de DiGeorge , Transtornos Psicóticos , Humanos , Síndrome de DiGeorge/complicações , Mapeamento Encefálico/métodos , Transtornos Psicóticos/complicações , Encéfalo/patologia , Cerebelo/diagnóstico por imagem , Cerebelo/patologia
10.
AJNR Am J Neuroradiol ; 44(1): 105-110, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36521966

RESUMO

Sarcoidosis is a multisystem granulomatous disease, with intramedullary spinal cord involvement seen in <1% of cases. This case series illustrates the clinical presentations and imaging findings of 5 patients with intramedullary spinal neurosarcoidosis occurring at sites of spondylotic spinal canal stenosis, which can be indistinguishable from spondylotic myelopathy with cord enhancement. Both entities are most common in middle-aged men and present with weeks to months of motor and sensory symptoms. On imaging, both can have focal spinal cord enhancement and longitudinally extensive signal abnormality centered at or just below the level of spinal canal stenosis. On the basis of our experience, we suggest that in patients with cord enhancement centered at or just below a site of spinal canal stenosis, consideration should be given to chest imaging and lymph node biopsy when applicable, to assess for the possibility of underlying sarcoidosis before surgical decompression.


Assuntos
Sarcoidose , Compressão da Medula Espinal , Doenças da Medula Espinal , Estenose Espinal , Espondilose , Masculino , Pessoa de Meia-Idade , Humanos , Constrição Patológica/patologia , Vértebras Cervicais/cirurgia , Doenças da Medula Espinal/diagnóstico por imagem , Doenças da Medula Espinal/patologia , Medula Espinal/diagnóstico por imagem , Medula Espinal/patologia , Estenose Espinal/diagnóstico por imagem , Estenose Espinal/patologia , Espondilose/diagnóstico por imagem , Sarcoidose/diagnóstico por imagem , Sarcoidose/patologia , Imageamento por Ressonância Magnética
11.
Behav Genet ; 53(1): 1-24, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36357558

RESUMO

Twin studies yield valuable insights into the sources of variation, covariation and causation in human traits. The ABCD Study® (abcdstudy.org) was designed to take advantage of four universities known for their twin research, neuroimaging, population-based sampling, and expertise in genetic epidemiology so that representative twin studies could be performed. In this paper we use the twin data to: (i) provide initial estimates of heritability for the wide range of phenotypes assessed in the ABCD Study using a consistent direct variance estimation approach, assuring that both data and methodology are sound; and (ii) provide an online resource for researchers that can serve as a reference point for future behavior genetic studies of this publicly available dataset. Data were analyzed from 772 pairs of twins aged 9-10 years at study inception, with zygosity determined using genotypic data, recruited and assessed at four twin hub sites. The online tool provides twin correlations and both standardized and unstandardized estimates of additive genetic, and environmental variation for 14,500 continuously distributed phenotypic features, including: structural and functional neuroimaging, neurocognition, personality, psychopathology, substance use propensity, physical, and environmental trait variables. The estimates were obtained using an unconstrained variance approach, so they can be incorporated directly into meta-analyses without upwardly biasing aggregate estimates. The results indicated broad consistency with prior literature where available and provided novel estimates for phenotypes without prior twin studies or those assessed at different ages. Effects of site, self-identified race/ethnicity, age and sex were statistically controlled. Results from genetic modeling of all 53,172 continuous variables, including 38,672 functional MRI variables, will be accessible via the user-friendly open-access web interface we have established, and will be updated as new data are released from the ABCD Study. This paper provides an overview of the initial results from the twin study embedded within the ABCD Study, an introduction to the primary research domains in the ABCD study and twin methodology, and an evaluation of the initial findings with a focus on data quality and suitability for future behavior genetic studies using the ABCD dataset. The broad introductory material is provided in recognition of the multidisciplinary appeal of the ABCD Study. While this paper focuses on univariate analyses, we emphasize the opportunities for multivariate, developmental and causal analyses, as well as those evaluating heterogeneity by key moderators such as sex, demographic factors and genetic background.


Assuntos
Doenças em Gêmeos , Gêmeos , Humanos , Gêmeos/genética , Fenótipo , Doenças em Gêmeos/genética , Neuroimagem , Imageamento por Ressonância Magnética , Gêmeos Dizigóticos/genética , Gêmeos Monozigóticos/genética
12.
Braz. j. biol ; 83: e245386, 2023. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1278528

RESUMO

Abstract Herbivory is an interaction with great impact on plant communities since relationships between herbivores and plants are fundamental to the distribution and abundance of species over time and space. The aim of this study was to monitor the rate of leaf expansion in the tree fern Cyathea phalerata and evaluate the damage caused by herbivores to leaves of different ages and whether such damage is related to temperature and precipitation. The study was performed in a subtropical Atlantic Forest fragment located in the municipality of Caraá, in the northeast hillside of Rio Grande do Sul state, in southern Brazil. We monitored 24 mature individuals of C. phalerata with croziers in a population of approximately 50 plants. Leaf expansion rate, percentage of damaged leaves and leaf blade consumption rate by herbivory were calculated. Monthly means for temperature and accumulated rainfall were calculated from daily data. Croziers of C. phalerata were found to expand rapidly during the first and second months after emergence (3.98 cm day-1; 2.91 cm day-1, respectively). Damage caused by herbivory was observed in all of the monitored leaves, but none of the plants experienced complete defoliation. The highest percentage (57%) of damaged leaves was recorded at 60 days of monitoring, and also the highest monthly consumption rate of the blade (6.04%) occurred with young, newly-expanded leaves, while this rate remained between 1.50 and 2.21% for mature leaves. Rates of monthly leaf consumption and damaged leaves showed positive and strong relationship with each other and with temperature. The rapid leaf expansion observed for C. phalerata can be considered a phenological strategy to reduce damage to young leaves by shortening the developmental period and accelerating the increase of defenses in mature leaves.


Resumo A herbivoria é uma interação de grande impacto sobre as comunidades de plantas, uma vez que as relações entre herbívoros e plantas são fundamentais para a distribuição e abundância das espécies ao longo do tempo e do espaço. O objetivo deste estudo foi monitorar a taxa de expansão foliar da samambaia arborescente Cyathea phalerata e avaliar o dano causado por herbívoros a folhas de diferentes idades, assim como verificar se este dano está relacionado à temperatura e à precipitação. O estudo foi realizado em um fragmento de Floresta Atlântica subtropical localizado no município de Caraá, na encosta nordeste do estado do Rio Grande do Sul, no sul do Brasil. Nós monitoramos 24 indivíduos maduros de C. phalerata com báculos em uma população de aproximadamente 50 plantas. A taxa de expansão foliar, a porcentagem de folhas danificadas e a taxa de consumo da lâmina foliar por herbivoria foram calculados. Médias mensais de temperatura e precipitação acumulada foram calculadas a partir de dados diários. Báculos de C. phalerata expandiram rapidamente durante o primeiro e o segundo mês após emergência (3,98 cm dia-1; 2,91 cm dia-1, respectivamente). O dano causado por herbivoria foi observado em todas as folhas monitoradas, mas nenhuma das plantas sofreu desfolhação completa. A maior porcentagem (57%) de folhas danificadas foi registrada aos 60 dias de monitoramento, e também a maior taxa de consumo mensal (6,04%) ocorreu em folhas jovens, recém expandidas, enquanto esta taxa permaneceu entre 1,50 e 2,21% em folhas maduras. As taxas mensais de consumo da lâmina foliar e de folhas danificadas mostraram relação positiva e forte entre si e com a temperatura. A rápida expansão foliar observada em C. phalerata pode ser considerada uma estratégia fenológica para reduzir o dano a folhas jovens, abreviando o período de desenvolvimento e acelerando o aumento das defesas em folhas maduras.


Assuntos
Humanos , Gleiquênias , Herbivoria , Brasil , Florestas , Folhas de Planta
13.
Braz. j. biol ; 83: 1-8, 2023. graf, tab
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1468812

RESUMO

Herbivory is an interaction with great impact on plant communities since relationships between herbivores and plants are fundamental to the distribution and abundance of species over time and space. The aim of this study was to monitor the rate of leaf expansion in the tree fern Cyathea phalerata and evaluate the damage caused by herbivores to leaves of different ages and whether such damage is related to temperature and precipitation. The study was performed in a subtropical Atlantic Forest fragment located in the municipality of Caraá, in the northeast hillside of Rio Grande do Sul state, in southern Brazil. We monitored 24 mature individuals of C. phalerata with croziers in a population of approximately 50 plants. Leaf expansion rate, percentage of damaged leaves and leaf blade consumption rate by herbivory were calculated. Monthly means for temperature and accumulated rainfall were calculated from daily data. Croziers of C. phalerata were found to expand rapidly during the first and second months after emergence (3.98 cm day-¹; 2.91 cm day-¹, respectively). Damage caused by herbivory was observed in all of the monitored leaves, but none of the plants experienced complete defoliation. The highest percentage (57%) of damaged leaves was recorded at 60 days of monitoring, and also the highest monthly consumption rate of the blade (6.04%) occurred with young, newly-expanded leaves, while this rate remained between 1.50 and 2.21% for mature leaves. Rates of monthly leaf consumption and damaged leaves showed positive and strong relationship with each other and with temperature. The rapid leaf expansion observed for C. phalerata can be considered a phenological strategy to reduce damage to young leaves by shortening the developmental period and accelerating the increase of defenses in mature leaves.


A herbivoria é uma interação de grande impacto sobre as comunidades de plantas, uma vez que as relações entre herbívoros e plantas são fundamentais para a distribuição e abundância das espécies ao longo do tempo e do espaço. O objetivo deste estudo foi monitorar a taxa de expansão foliar da samambaia arborescente Cyathea phalerata e avaliar o dano causado por herbívoros a folhas de diferentes idades, assim como verificar se este dano está relacionado à temperatura e à precipitação. O estudo foi realizado em um fragmento de Floresta Atlântica subtropical localizado no município de Caraá, na encosta nordeste do estado do Rio Grande do Sul, no sul do Brasil. Nós monitoramos 24 indivíduos maduros de C. phalerata com báculos em uma população de aproximadamente 50 plantas. A taxa de expansão foliar, a porcentagem de folhas danificadas e a taxa de consumo da lâmina foliar por herbivoria foram calculados. Médias mensais de temperatura e precipitação acumulada foram calculadas a partir de dados diários. Báculos de C. phalerata expandiram rapidamente durante o primeiro e o segundo mês após emergência (3,98 cm dia-¹; 2,91 cm dia-¹, respectivamente). O dano causado por herbivoria foi observado em todas as folhas monitoradas, mas nenhuma das plantas sofreu desfolhação completa. A maior porcentagem (57%) de folhas danificadas foi registrada aos 60 dias de monitoramento, e também a maior taxa de consumo mensal (6,04%) ocorreu em folhas jovens, recém expandidas, enquanto esta taxa permaneceu entre 1,50 e 2,21% em folhas maduras. As taxas mensais de consumo da lâmina foliar e de folhas danificadas mostraram relação positiva e forte entre si e com a temperatura. A rápida expansão foliar observada em C. phalerata pode ser considerada uma estratégia fenológica para reduzir o dano a folhas jovens, abreviando o período de desenvolvimento e acelerando o aumento das defesas em folhas maduras.


Assuntos
Gleiquênias/crescimento & desenvolvimento , Herbivoria
14.
Braz. j. biol ; 832023.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469028

RESUMO

Abstract Herbivory is an interaction with great impact on plant communities since relationships between herbivores and plants are fundamental to the distribution and abundance of species over time and space. The aim of this study was to monitor the rate of leaf expansion in the tree fern Cyathea phalerata and evaluate the damage caused by herbivores to leaves of different ages and whether such damage is related to temperature and precipitation. The study was performed in a subtropical Atlantic Forest fragment located in the municipality of Caraá, in the northeast hillside of Rio Grande do Sul state, in southern Brazil. We monitored 24 mature individuals of C. phalerata with croziers in a population of approximately 50 plants. Leaf expansion rate, percentage of damaged leaves and leaf blade consumption rate by herbivory were calculated. Monthly means for temperature and accumulated rainfall were calculated from daily data. Croziers of C. phalerata were found to expand rapidly during the first and second months after emergence (3.98 cm day-1; 2.91 cm day-1, respectively). Damage caused by herbivory was observed in all of the monitored leaves, but none of the plants experienced complete defoliation. The highest percentage (57%) of damaged leaves was recorded at 60 days of monitoring, and also the highest monthly consumption rate of the blade (6.04%) occurred with young, newly-expanded leaves, while this rate remained between 1.50 and 2.21% for mature leaves. Rates of monthly leaf consumption and damaged leaves showed positive and strong relationship with each other and with temperature. The rapid leaf expansion observed for C. phalerata can be considered a phenological strategy to reduce damage to young leaves by shortening the developmental period and accelerating the increase of defenses in mature leaves.


Resumo A herbivoria é uma interação de grande impacto sobre as comunidades de plantas, uma vez que as relações entre herbívoros e plantas são fundamentais para a distribuição e abundância das espécies ao longo do tempo e do espaço. O objetivo deste estudo foi monitorar a taxa de expansão foliar da samambaia arborescente Cyathea phalerata e avaliar o dano causado por herbívoros a folhas de diferentes idades, assim como verificar se este dano está relacionado à temperatura e à precipitação. O estudo foi realizado em um fragmento de Floresta Atlântica subtropical localizado no município de Caraá, na encosta nordeste do estado do Rio Grande do Sul, no sul do Brasil. Nós monitoramos 24 indivíduos maduros de C. phalerata com báculos em uma população de aproximadamente 50 plantas. A taxa de expansão foliar, a porcentagem de folhas danificadas e a taxa de consumo da lâmina foliar por herbivoria foram calculados. Médias mensais de temperatura e precipitação acumulada foram calculadas a partir de dados diários. Báculos de C. phalerata expandiram rapidamente durante o primeiro e o segundo mês após emergência (3,98 cm dia-1; 2,91 cm dia-1, respectivamente). O dano causado por herbivoria foi observado em todas as folhas monitoradas, mas nenhuma das plantas sofreu desfolhação completa. A maior porcentagem (57%) de folhas danificadas foi registrada aos 60 dias de monitoramento, e também a maior taxa de consumo mensal (6,04%) ocorreu em folhas jovens, recém expandidas, enquanto esta taxa permaneceu entre 1,50 e 2,21% em folhas maduras. As taxas mensais de consumo da lâmina foliar e de folhas danificadas mostraram relação positiva e forte entre si e com a temperatura. A rápida expansão foliar observada em C. phalerata pode ser considerada uma estratégia fenológica para reduzir o dano a folhas jovens, abreviando o período de desenvolvimento e acelerando o aumento das defesas em folhas maduras.

15.
Front Bioinform ; 2: 865443, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36304320

RESUMO

Segmentation of mouse brain magnetic resonance images (MRI) based on anatomical and/or functional features is an important step towards morphogenetic brain structure characterization of murine models in neurobiological studies. State-of-the-art image segmentation methods register image volumes to standard presegmented templates or well-characterized highly detailed image atlases. Performance of these methods depends critically on the quality of skull-stripping, which is the digital removal of tissue signal exterior to the brain. This is, however, tedious to do manually and challenging to automate. Registration-based segmentation, in addition, performs poorly on small structures, low resolution images, weak signals, or faint boundaries, intrinsic to in vivo MRI scans. To address these issues, we developed an automated end-to-end pipeline called DeepBrainIPP (deep learning-based brain image processing pipeline) for 1) isolating brain volumes by stripping skull and tissue from T2w MRI images using an improved deep learning-based skull-stripping and data augmentation strategy, which enables segmentation of large brain regions by atlas or template registration, and 2) address segmentation of small brain structures, such as the paraflocculus, a small lobule of the cerebellum, for which DeepBrainIPP performs direct segmentation with a dedicated model, producing results superior to the skull-stripping/atlas-registration paradigm. We demonstrate our approach on data from both in vivo and ex vivo samples, using an in-house dataset of 172 images, expanded to 4,040 samples through data augmentation. Our skull stripping model produced an average Dice score of 0.96 and residual volume of 2.18%. This facilitated automatic registration of the skull-stripped brain to an atlas yielding an average cross-correlation of 0.98. For small brain structures, direct segmentation yielded an average Dice score of 0.89 and 5.32% residual volume error, well below the tolerance threshold for phenotype detection. Full pipeline execution is provided to non-expert users via a Web-based interface, which exposes analysis parameters, and is powered by a service that manages job submission, monitors job status and provides job history. Usability, reliability, and user experience of DeepBrainIPP was measured using the Customer Satisfaction Score (CSAT) and a modified PYTHEIA Scale, with a rating of excellent. DeepBrainIPP code, documentation and network weights are freely available to the research community.

16.
Rev Med Liege ; 77(10): 586-592, 2022 Oct.
Artigo em Francês | MEDLINE | ID: mdl-36226395

RESUMO

The evaluation of anti-HLA immunization in organ transplantation has evolved dramatically since the first lymphocytotoxic crossmatch between donor and recipient was described. The same is true for HLA typing, which can now be performed by high-resolution sequencing. Nevertheless, the transplantation of a totally compatible organ remains an exception and the appearance of anti-HLA antibodies during the transplantation is inevitable, which conditions the long-term survival of the graft. New computer tools are currently being developed to evaluate and quantify the degree of incompatibility between donor and recipient, with a view to predicting the risk of rejection and adapting immunosuppressive therapy in a targeted manner for each patient.


L'évaluation de l'immunisation anti-HLA dans la transplantation d'organe a évolué de façon spectaculaire depuis la description des premiers crossmatchs par lymphocytotoxicité entre donneur et receveur. Il en est de même pour le typage HLA, qui peut maintenant être réalisé par séquençage en haute résolution. Néanmoins, la greffe d'organe totalement compatible reste une exception et l'apparition d'anticorps anti-HLA dans le décours de la greffe est inévitable, ce qui conditionne la survie du greffon à long terme. De nouveaux outils informatiques sont actuellement développés pour évaluer et quantifier le degré d'incompatibilité entre donneur et receveur, dans la perspective de prédire le risque de rejet et adapter la thérapie immunosuppressive de façon ciblée pour chaque patient.


Assuntos
Antígenos HLA , Transplante de Órgãos , Rejeição de Enxerto/prevenção & controle , Sobrevivência de Enxerto , Antígenos HLA/genética , Histocompatibilidade , Humanos
17.
JAMA Psychiatry ; 79(7): 699-709, 2022 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-35544191

RESUMO

Importance: Psychiatric and cognitive phenotypes have been associated with a range of specific, rare copy number variants (CNVs). Moreover, IQ is strongly associated with CNV risk scores that model the predicted risk of CNVs across the genome. But the utility of CNV risk scores for psychiatric phenotypes has been sparsely examined. Objective: To determine how CNV risk scores, common genetic variation indexed by polygenic scores (PGSs), and environmental factors combine to associate with cognition and psychopathology in a community sample. Design, Setting, and Participants: The Philadelphia Neurodevelopmental Cohort is a community-based study examining genetics, psychopathology, neurocognition, and neuroimaging. Participants were recruited through the Children's Hospital of Philadelphia pediatric network. Participants with stable health and fluency in English underwent genotypic and phenotypic characterization from November 5, 2009, through December 30, 2011. Data were analyzed from January 1 through July 30, 2021. Exposures: The study examined (1) CNV risk scores derived from models of burden, predicted intolerance, and gene dosage sensitivity; (2) PGSs from genomewide association studies related to developmental outcomes; and (3) environmental factors, including trauma exposure and neighborhood socioeconomic status. Main Outcomes and Measures: The study examined (1) neurocognition, with the Penn Computerized Neurocognitive Battery; (2) psychopathology, with structured interviews based on the Schedule for Affective Disorders and Schizophrenia for School-Age Children; and (3) brain volume, with magnetic resonance imaging. Results: Participants included 9498 youths aged 8 to 21 years; 4906 (51.7%) were female, and the mean (SD) age was 14.2 (3.7) years. After quality control, 18 185 total CNVs greater than 50 kilobases (10 517 deletions and 7668 duplications) were identified in 7101 unrelated participants genotyped on Illumina arrays. In these participants, elevated CNV risk scores were associated with lower overall accuracy on cognitive tests (standardized ß = 0.12; 95% CI, 0.10-0.14; P = 7.41 × 10-26); lower accuracy across a range of cognitive subdomains; increased overall psychopathology; increased psychosis-spectrum symptoms; and higher deviation from a normative developmental model of brain volume. Statistical models of developmental outcomes were significantly improved when CNV risk scores were combined with PGSs and environmental factors. Conclusions and Relevance: In this study, elevated CNV risk scores were associated with lower cognitive ability, higher psychopathology including psychosis-spectrum symptoms, and greater deviations from normative magnetic resonance imaging models of brain development. Together, these results represent a step toward synthesizing rare genetic, common genetic, and environmental factors to understand clinically relevant outcomes in youth.


Assuntos
Variações do Número de Cópias de DNA , Transtornos Psicóticos , Adolescente , Encéfalo/diagnóstico por imagem , Criança , Cognição , Variações do Número de Cópias de DNA/genética , Feminino , Humanos , Masculino , Transtornos Psicóticos/genética , Transtornos Psicóticos/psicologia , Fatores de Risco
18.
Herzschrittmacherther Elektrophysiol ; 33(2): 247-254, 2022 Jun.
Artigo em Alemão | MEDLINE | ID: mdl-35604450

RESUMO

Programming of implantable cardiac devices, especially dual-chamber pacemakers, can be challenging in daily clinical practice. Precise knowledge of programmable parameters is important; furthermore, one should also be familiar with the specific algorithms of each manufacturer. During programming, the patient's individual requirements should be taken into account, but out-of-the-box programming should be avoided. Another important goal of programming should be to stimulate as much as needed but as little as possible to provide the patient good exercise capacity while not being aware of the pacing. Manufacturers' algorithms can help reach these aims but need to be understood and-in case of inappropriate behavior-to be deactivated.


Assuntos
Estimulação Cardíaca Artificial/normas , Eletrodos Implantados/normas , Marca-Passo Artificial , Software/normas , Algoritmos , Estimulação Cardíaca Artificial/métodos , Estimulação Cardíaca Artificial/tendências , Eletrodos Implantados/tendências , Humanos , Marca-Passo Artificial/normas , Software/tendências
19.
J Eur Acad Dermatol Venereol ; 36(4): 547-556, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34779040

RESUMO

BACKGROUND: Hand eczema is a common inflammatory skin disorder in both adolescence and adulthood. OBJECTIVES: We sought to assess the lifetime prevalence of hand eczema and associated exogenous and endogenous risk factors among adolescents in Germany. METHODS: This was a cross-sectional study embedded into a prospective population-based birth cohort in four regions of Germany, which recruited healthy neonates born between November 1997 and January 1999. We included 1736 participants who had completed the 15-year follow-up from birth cohort and 84.6% (1468/1736) had clearly reported whether they have ever had hand eczema. All the data were based on questionnaires and blood tests (immunoglobulin E). Multivariable logistic regression analysis was used to examine endogenous and exogenous factors in relation to the lifetime prevalence of hand eczema among adolescents. RESULTS: One thousand four hundred and sixty-eight adolescents (715 girls, 48.7%) were included in the final analysis. The lifetime prevalence of hand eczema among adolescents at the age of 15 was 10.4% (95% confidence interval [CI]: 8.9%-12.1%), with a significantly higher lifetime prevalence among girls than boys (12.7% vs. 8.2%, P = 0.005). Multivariable logistic regression analysis indicated statistically significant associations between the lifetime prevalence of hand eczema and having ever been diagnosed with atopic dermatitis (aOR = 1.8, 95% CI: 1.1-2.8) or having ever had dry skin (aOR = 1.9, 95% CI: 1.1-3.1), respectively. No statistically significant independent associations were found between asthma, hay fever, allergy-related clinical symptoms, immunoglobulin E positivity and other exogenous factors in relation to hand eczema. CONCLUSION: Our study fills a research gap on the epidemiological burden of hand eczema among adolescents. One out of ten ever suffered from hand eczema until age 15 years indicating that hand eczema constitutes a significant burden in paediatric populations. The role of atopic dermatitis in hand eczema reinforces previous findings. Exogenous risk factors warrant further investigation.


Assuntos
Eczema , Adolescente , Adulto , Criança , Estudos de Coortes , Estudos Transversais , Eczema/epidemiologia , Eczema/etiologia , Feminino , Seguimentos , Alemanha/epidemiologia , Humanos , Recém-Nascido , Masculino , Prevalência , Estudos Prospectivos , Fatores de Risco
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