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1.
Proc Natl Acad Sci U S A ; 121(13): e2312988121, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38498714

RESUMO

One of the fundamental steps toward understanding a complex system is identifying variation at the scale of the system's components that is most relevant to behavior on a macroscopic scale. Mutual information provides a natural means of linking variation across scales of a system due to its independence of functional relationship between observables. However, characterizing the manner in which information is distributed across a set of observables is computationally challenging and generally infeasible beyond a handful of measurements. Here, we propose a practical and general methodology that uses machine learning to decompose the information contained in a set of measurements by jointly optimizing a lossy compression of each measurement. Guided by the distributed information bottleneck as a learning objective, the information decomposition identifies the variation in the measurements of the system state most relevant to specified macroscale behavior. We focus our analysis on two paradigmatic complex systems: a Boolean circuit and an amorphous material undergoing plastic deformation. In both examples, the large amount of entropy of the system state is decomposed, bit by bit, in terms of what is most related to macroscale behavior. The identification of meaningful variation in data, with the full generality brought by information theory, is made practical for studying the connection between micro- and macroscale structure in complex systems.

2.
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
3.
Phys Rev Lett ; 132(19): 197201, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38804957

RESUMO

Deterministic chaos permits a precise notion of a "perfect measurement" as one that, when obtained repeatedly, captures all of the information created by the system's evolution with minimal redundancy. Finding an optimal measurement is challenging and has generally required intimate knowledge of the dynamics in the few cases where it has been done. We establish an equivalence between a perfect measurement and a variant of the information bottleneck. As a consequence, we can employ machine learning to optimize measurement processes that efficiently extract information from trajectory data. We obtain approximately optimal measurements for multiple chaotic maps and lay the necessary groundwork for efficient information extraction from general time series.

4.
Neuroradiology ; 66(1): 1-30, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37828278

RESUMO

Tarlov cysts were thought to be anatomic variants of uncertain etiology and clinical significance when initially described over 80 years ago. They are often detected in routine lumbosacral imaging and generally not reported in a differential diagnosis. There is increasing evidence that at least some Tarlov cysts are symptomatic and can have a significant adverse impact on patients' health and well-being. Women are disproportionately affected with this condition, often presenting with long-standing pain and neurological dysfunctions. Significant gender bias has been a concern in the management of these patients. Unfortunately, there is no consensus on patient selection or management approaches for symptomatic Tarlov cysts. This review article updates information on the prevalence, diagnosis, clinical significance, and treatments of these cysts. Based on these findings and experience with over 1000 patient referrals, a treatment decision algorithm for symptomatic Tarlov cysts was constructed to provide guidance for appropriate management of patients with these complex cysts.


Assuntos
Doenças da Coluna Vertebral , Cistos de Tarlov , Humanos , Masculino , Feminino , Cistos de Tarlov/diagnóstico por imagem , Cistos de Tarlov/terapia , Imageamento por Ressonância Magnética , Sexismo , Doenças da Coluna Vertebral/diagnóstico por imagem , Doenças da Coluna Vertebral/terapia , Sacro
5.
Can Assoc Radiol J ; : 8465371241256908, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38859655

RESUMO

Purpose: Fractal analysis is a mathematical tool which allows the evaluation of complex microstructural features within materials that cannot be expressed in traditional geometric terms. The purpose of this study is to quantify the differences in polymethylmethacrylate intravertebral cement spatial distribution patterns following vertebroplasty using fractal analysis through the examination of osteoporotic and malignant compression fractures. Methods: Frontal and lateral post-vertebroplasty radiographs were evaluated from 29 patients with osteoporotic and malignant compression fractures who underwent vertebroplasty. The individually treated vertebra were divided into osteoporotic (n = 35) and malignant groups (n = 41). Images underwent segmentation, thresholding, and binarization prior to fractal analysis. Fractal dimension and lacunarity values were derived from the region of interest in treated vertebrae using the "box-counting" and "gliding-box" techniques respectively using ImageJ. The mean values of both parameters were compared between the 2 groups. Results: The mean fractal dimension was significantly higher in the malignant vertebral compression fracture group (1.53 ± 0.08) compared to the osteoporotic group (1.34 ± 0.17; P < .001). Similarly, mean lacunarity values were significantly higher in the malignant fracture group (0.50 ± 0.09) compared to the osteoporotic group (0.37 ± 0.10; P < .001). Conclusions: Fractal dimension and lacunarity values of cement spatial distribution patterns obtained from the post-vertebroplasty radiographs can differentiate between benign osteoporotic and malignant vertebral compression fractures. This novel technique may be useful for evaluating cement spatial distribution patterns in spine augmentation procedures, although further research is warranted in this area.

6.
Lab Invest ; 103(9): 100198, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37321542

RESUMO

Formalin, a common laboratory fixative, is a type 1 carcinogen; a biohazard with risks, environmental, disposal, and legal costs; and a chemical modifier of protein epitopes in tissues. A less-toxic tissue preservation method is therefore badly needed. We have developed a novel tissue preservation medium, Amber, composed of low-potassium dextran glucose, 10% honey, and 1% coconut oil. This study investigates Amber as compared with formalin with respect to the following aspects: (1) histologic preservation, (2) epitope integrity with immunohistochemistry (IHC) and immunofluorescence (IF), and (3) integrity of tissue RNA. Rat and human lung, liver, kidney, and heart tissues were collected and stored for 24 hours at 4 °C in Amber or formalin. The tissues were evaluated with hematoxylin and eosin; IHC: thyroid transcription factor, muscle-specific actin, hepatocyte-specific antigen, and common acute lymphoblastic leukemia antigen; and IF: VE-cadherin, vimentin, and muscle-specific actin. RNA quality upon extraction was also assessed. Amber demonstrated superior and/or noninferior performance in rat and human tissue evaluation with respect to standard techniques of histology, IHC, IF, and extracted RNA quality. Amber maintains high-quality morphology without compromising the ability to perform IHC and nucleic acid extraction. As such, Amber could be a safer and superior substitute to formalin for clinical tissue preservation for contemporary pathological examination.


Assuntos
Actinas , Formaldeído , Ratos , Humanos , Animais , Âmbar , Fixadores , Preservação de Tecido/métodos , RNA , Antígenos , Fixação de Tecidos/métodos
7.
Am J Hum Genet ; 106(1): 26-40, 2020 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-31870554

RESUMO

The 22q11.2 deletion syndrome (22q11.2DS) results from non-allelic homologous recombination between low-copy repeats termed LCR22. About 60%-70% of individuals with the typical 3 megabase (Mb) deletion from LCR22A-D have congenital heart disease, mostly of the conotruncal type (CTD), whereas others have normal cardiac anatomy. In this study, we tested whether variants in the hemizygous LCR22A-D region are associated with risk for CTDs on the basis of the sequence of the 22q11.2 region from 1,053 22q11.2DS individuals. We found a significant association (FDR p < 0.05) of the CTD subset with 62 common variants in a single linkage disequilibrium (LD) block in a 350 kb interval harboring CRKL. A total of 45 of the 62 variants were associated with increased risk for CTDs (odds ratio [OR) ranges: 1.64-4.75). Associations of four variants were replicated in a meta-analysis of three genome-wide association studies of CTDs in affected individuals without 22q11.2DS. One of the replicated variants, rs178252, is located in an open chromatin region and resides in the double-elite enhancer, GH22J020947, that is predicted to regulate CRKL (CRK-like proto-oncogene, cytoplasmic adaptor) expression. Approximately 23% of patients with nested LCR22C-D deletions have CTDs, and inactivation of Crkl in mice causes CTDs, thus implicating this gene as a modifier. Rs178252 and rs6004160 are expression quantitative trait loci (eQTLs) of CRKL. Furthermore, set-based tests identified an enhancer that is predicted to target CRKL and is significantly associated with CTD risk (GH22J020946, sequence kernal association test (SKAT) p = 7.21 × 10-5) in the 22q11.2DS cohort. These findings suggest that variance in CTD penetrance in the 22q11.2DS population can be explained in part by variants affecting CRKL expression.


Assuntos
Deleção Cromossômica , Cromossomos Humanos Par 22/genética , Cardiopatias Congênitas/genética , Polimorfismo de Nucleotídeo Único , Estudos de Casos e Controles , Estudos de Coortes , Feminino , Estudo de Associação Genômica Ampla , Cardiopatias Congênitas/patologia , Humanos , Desequilíbrio de Ligação , Masculino , Fenótipo , Proto-Oncogene Mas , Duplicações Segmentares Genômicas
8.
J Vasc Interv Radiol ; 34(4): 563-567, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36539152

RESUMO

PURPOSE: To evaluate the prevalence of surface lead-dust contamination on radiation protection apparel (RPAs) in the radiology department and compare findings with those from other studies of RPA lead-dust contamination. MATERIALS AND METHODS: A survey of RPAs was conducted between June and December 2021 in radiology departments at a tertiary-care university hospital. A convenience sample of RPAs located on wall-mounted racks outside the angiography suite and emergency department was surveyed. Surface lead dust on RPAs was detected using a rapid qualitative test. RESULTS: A total of 69 RPAs included full-length frontal lead aprons (n = 11), full-length frontal lead aprons (n = 25) with thyroid collars (n = 25), and thyroid collars alone (n = 8). Garments consisted mainly of a lead/antimony composite core with a 0.5-mm lead equivalency. One RPA failed radiologic quality inspection, and 8 garments were in poor or worn condition. The overall prevalence of surface lead-dust contamination on RPAs was 60.9% (95% CI, 49.1%-71.5%) and was significantly (P = .0035) higher on thyroid collars (78.8% [95% CI, 62.2%-89.3%]) than on lead aprons (44.4% [95% CI, 29.5%-60.4%]). CONCLUSIONS: A high prevalence of surface lead-dust contamination was detected on RPAs using a rapid qualitative test. There is currently no established safe level of lead, and these findings suggest RPAs be monitored frequently not only for physical defects limiting radiation protection but also for lead-dust contamination.


Assuntos
Proteção Radiológica , Serviço Hospitalar de Radiologia , Humanos , Doses de Radiação , Poeira , Roupa de Proteção
9.
Biol Lett ; 19(10): 20230142, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37875159

RESUMO

Body-size relationships between predators and prey exhibit remarkable diversity. However, the assumption that predators typically consume proportionally smaller prey often underlies size-dependent predation in ecosystem models. In reality, some animals can consume larger prey or exhibit limited changes in prey size as they grow larger themselves. These distinct predator-prey size relationships challenge the conventional assumptions of traditional size-based models. Cephalopods, with their diverse feeding behaviours and life histories, offer an excellent case study to investigate the impact of greater biological realism in predator-prey size relationships on energy flow within a size-structured ecosystem model. By categorizing cephalopods into high and low-activity groups, in line with empirically derived, distinct predator-prey size relationships, we found that incorporating greater biological realism in size-based feeding reduced ecosystem biomass and production, while simultaneously increasing biomass stability and turnover. Our results have broad implications for ecosystem modelling, since distinct predator-prey size relationships extend beyond cephalopods, encompassing a wide array of major taxonomic groups from filter-feeding fishes to baleen whales. Incorporating a diversity of size-based feeding in food web models can enhance their ecological and predictive accuracy when studying ecosystem dynamics.


Assuntos
Ecossistema , Cadeia Alimentar , Animais , Biomassa , Tamanho Corporal , Comportamento Alimentar , Comportamento Predatório , Modelos Biológicos
10.
Int J Mol Sci ; 24(7)2023 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-37047063

RESUMO

Cancer is an escalating global issue, with 19.3 million new cases and 9.9 million deaths in 2020. Therefore, effective approaches to prevent cancer are urgently required. Diet plays a significant role in determining cancer risk. Nutrients and food bioactives influence specific signaling pathways in the body. Recently, there have been significant advances in cancer prevention research through nutrigenomics or with the effects of dietary components on the genome. Google Scholar, PubMed, and Scopus databases were used to search for peer-reviewed articles between 2017 and 2023. Criteria used were vitamins, minerals, tumors, cancer, genes, inflammation, signaling pathways, and nutrigenomics. Among the total of 1857 articles available, the highest relevant 90 articles that specifically discussed signaling pathways and genes on cancer cell lines and human cancer patients were selected and reviewed. Food sources are rich in antioxidant micronutrients, which are effective in activating or regulating signaling pathways involved in pathogenesis and cancer therapy by activating enzymes such as mitogen-activated protein kinase (MAPK), protein kinase C (PKC), and phosphatidylinositol 3-kinase (PI3K). The micronutrients are involved in the regulation of ß-catenin (WNT/ß-catenin) including mutations in Kras and epidermal growth factor receptor (EGFR) alongside inhibition of the NF-kB pathway. The most common mechanism of cancer prevention by these micronutrients is their antioxidative, anti-inflammation, and anti-apoptosis effects. This review discusses how nutrigenomics is essential and beneficial for developing cancer prevention and treatment approaches.


Assuntos
Neoplasias , Vitaminas , Humanos , Vitaminas/farmacologia , Vitaminas/uso terapêutico , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Micronutrientes/farmacologia , Micronutrientes/uso terapêutico , beta Catenina/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Transdução de Sinais , Vitamina A , Vitamina K , Neoplasias/tratamento farmacológico , Neoplasias/genética , Neoplasias/prevenção & controle
11.
Soft Matter ; 18(10): 2039-2045, 2022 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-35194630

RESUMO

Disordered-Network Mechanical Materials (DNMM), comprised of random arrangements of bonds and nodes, have emerged as mechanical metamaterials with the potential for achieving fine control over their mechanical properties. Recent computational studies have demonstrated this control whereby an extremely high degree of mechanical tunability can be achieved in disordered networks via a selective bond removal process called pruning. In this study, we experimentally demonstrate how pruning of a disordered network alters its macroscopic dynamic mechanical response and its capacity to mitigate impact. Impact studies with velocities ranging from 0.1 m s-1 to 1.5 m s-1 were performed, using a mechanical impactor and a drop tower, on 3D printed pruned and unpruned networks comprised of materials spanning a range of stiffness. High-speed videography was used to quantify the changes in Poisson's ratio for each of the network samples. Our results demonstrate that pruning is an efficient way to reduce the transmitted force and impulse from impact in the medium strain rate regime (101 s-1 to 102 s-1). This approach provides an interesting alternative route for designing materials with tailored impact mitigating properties compared to random material removal based on open cell foams.

12.
Ecol Appl ; : e2772, 2022 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-36316814

RESUMO

Elucidating processes and mechanisms involved in rapid local adaptation to varied environments is a poorly understood but crucial component in management of invasive species. Recent studies have proposed that genetic and epigenetic variation could both contribute to ecological adaptation, yet it remains unclear on the interplay between these two components underpinning rapid adaptation in wild animal populations. To assess their respective contributions to local adaptation, we explored epigenomic and genomic responses to environmental heterogeneity in eight recently colonized ascidian (Ciona intestinalis) populations at a relatively fine geographical scale. Based on MethylRADseq data, we detected strong patterns of local environment-driven DNA methylation divergence among populations, significant epigenetic isolation by environment (IBE), and a large number of local environment-associated epigenetic loci. Meanwhile, multiple genetic analyses based on single nucleotide polymorphisms (SNPs) showed genomic footprints of divergent selection. In addition, for five genetically similar populations, we detected significant methylation divergence and local environment-driven methylation patterns, indicating the strong effects of local environments on epigenetic variation. From a functional perspective, a majority of functional genes, Gene Ontology (GO) terms, and biological pathways were largely specific to one of these two types of variation, suggesting partial independence between epigenetic and genetic adaptation. The methylation quantitative trait loci (mQTL) analysis showed that the genetic variation explained only 18.67% of methylation variation, further confirming the autonomous relationship between these two types of variation. Altogether, we highlight the complementary interplay of genetic and epigenetic variation involved in local adaptation, which may jointly promote populations' rapid adaptive capacity and successful invasions in different environments. The findings here provide valuable insights into interactions between invaders and local environments to allow invasive species to rapidly spread, thus contributing to better prediction of invasion success and development of management strategies.

13.
Radiology ; 301(3): 502-514, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34665028

RESUMO

Normal physiologic function of organs requires a circulation of interstitial fluid to deliver nutrients and clear cellular waste products. Lymphatic vessels serve as collectors of this fluid in most organs; however, these vessels are absent in the central nervous system. How the central nervous system maintains tight control of extracellular conditions has been a fundamental question in neuroscience until recent discovery of the glial-lymphatic, or glymphatic, system was made this past decade. Networks of paravascular channels surrounding pial and parenchymal arteries and veins were found that extend into the walls of capillaries to allow fluid transport and exchange between the interstitial and cerebrospinal fluid spaces. The currently understood anatomy and physiology of the glymphatic system is reviewed, with the paravascular space presented as an intrinsic component of healthy pial and parenchymal cerebral blood vessels. Glymphatic system behavior in animal models of health and disease, and its enhanced function during sleep, are discussed. The evolving understanding of glymphatic system characteristics is then used to provide a current interpretation of its physiology that can be helpful for radiologists when interpreting neuroimaging investigations.


Assuntos
Líquido Extracelular/fisiologia , Sistema Glinfático/anatomia & histologia , Sistema Glinfático/fisiologia , Neuroimagem/métodos , Humanos
14.
Radiology ; 301(3): 516-532, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34698564

RESUMO

The glymphatic system is a recently discovered network unique to the central nervous system that allows for dynamic exchange of interstitial fluid (ISF) and cerebrospinal fluid (CSF). As detailed in part I, ISF and CSF transport along paravascular channels of the penetrating arteries and possibly veins allow essential clearance of neurotoxic solutes from the interstitium to the CSF efflux pathways. Imaging tests to investigate this neurophysiologic function, although challenging, are being developed and are reviewed herein. These include direct visualization of CSF transport using postcontrast imaging techniques following intravenous or intrathecal administration of contrast material and indirect glymphatic assessment with detection of enlarged perivascular spaces. Application of MRI techniques, including intravoxel incoherent motion, diffusion tensor imaging, and chemical exchange saturation transfer, is also discussed, as are methods for imaging dural lymphatic channels involved with CSF efflux. Subsequently, glymphatic function is considered in the context of proteinopathies associated with neurodegenerative diseases and traumatic brain injury, cytotoxic edema following acute ischemic stroke, and chronic hydrocephalus after subarachnoid hemorrhage. These examples highlight the substantial role of the glymphatic system in neurophysiology and the development of certain neuropathologic abnormalities, stressing the importance of its consideration when interpreting neuroimaging investigations. © RSNA, 2021.


Assuntos
Líquido Extracelular/diagnóstico por imagem , Líquido Extracelular/fisiologia , Sistema Glinfático/diagnóstico por imagem , Sistema Glinfático/fisiologia , Imageamento por Ressonância Magnética/métodos , Neuroimagem/métodos , Animais , Humanos , Camundongos
15.
Mol Psychiatry ; 25(11): 2818-2831, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-31358905

RESUMO

22q11.2 deletion syndrome (22q11DS)-a neurodevelopmental condition caused by a hemizygous deletion on chromosome 22-is associated with an elevated risk of psychosis and other developmental brain disorders. Prior single-site diffusion magnetic resonance imaging (dMRI) studies have reported altered white matter (WM) microstructure in 22q11DS, but small samples and variable methods have led to contradictory results. Here we present the largest study ever conducted of dMRI-derived measures of WM microstructure in 22q11DS (334 22q11.2 deletion carriers and 260 healthy age- and sex-matched controls; age range 6-52 years). Using harmonization protocols developed by the ENIGMA-DTI working group, we identified widespread reductions in mean, axial and radial diffusivities in 22q11DS, most pronounced in regions with major cortico-cortical and cortico-thalamic fibers: the corona radiata, corpus callosum, superior longitudinal fasciculus, posterior thalamic radiations, and sagittal stratum (Cohen's d's ranging from -0.9 to -1.3). Only the posterior limb of the internal capsule (IC), comprised primarily of corticofugal fibers, showed higher axial diffusivity in 22q11DS. 22q11DS patients showed higher mean fractional anisotropy (FA) in callosal and projection fibers (IC and corona radiata) relative to controls, but lower FA than controls in regions with predominantly association fibers. Psychotic illness in 22q11DS was associated with more substantial diffusivity reductions in multiple regions. Overall, these findings indicate large effects of the 22q11.2 deletion on WM microstructure, especially in major cortico-cortical connections. Taken together with findings from animal models, this pattern of abnormalities may reflect disrupted neurogenesis of projection neurons in outer cortical layers.


Assuntos
Síndrome de DiGeorge/diagnóstico por imagem , Síndrome de DiGeorge/patologia , Imagem de Difusão por Ressonância Magnética , Substância Branca/diagnóstico por imagem , Substância Branca/patologia , Adolescente , Adulto , Anisotropia , Criança , Síndrome de DiGeorge/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
16.
Mol Psychiatry ; 25(8): 1822-1834, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-29895892

RESUMO

The 22q11.2 deletion (22q11DS) is a common chromosomal microdeletion and a potent risk factor for psychotic illness. Prior studies reported widespread cortical changes in 22q11DS, but were generally underpowered to characterize neuroanatomic abnormalities associated with psychosis in 22q11DS, and/or neuroanatomic effects of variability in deletion size. To address these issues, we developed the ENIGMA (Enhancing Neuro Imaging Genetics Through Meta-Analysis) 22q11.2 Working Group, representing the largest analysis of brain structural alterations in 22q11DS to date. The imaging data were collected from 10 centers worldwide, including 474 subjects with 22q11DS (age = 18.2 ± 8.6; 46.9% female) and 315 typically developing, matched controls (age = 18.0 ± 9.2; 45.9% female). Compared to controls, 22q11DS individuals showed thicker cortical gray matter overall (left/right hemispheres: Cohen's d = 0.61/0.65), but focal thickness reduction in temporal and cingulate cortex. Cortical surface area (SA), however, showed pervasive reductions in 22q11DS (left/right hemispheres: d = -1.01/-1.02). 22q11DS cases vs. controls were classified with 93.8% accuracy based on these neuroanatomic patterns. Comparison of 22q11DS-psychosis to idiopathic schizophrenia (ENIGMA-Schizophrenia Working Group) revealed significant convergence of affected brain regions, particularly in fronto-temporal cortex. Finally, cortical SA was significantly greater in 22q11DS cases with smaller 1.5 Mb deletions, relative to those with typical 3 Mb deletions. We found a robust neuroanatomic signature of 22q11DS, and the first evidence that deletion size impacts brain structure. Psychotic illness in this highly penetrant deletion was associated with similar neuroanatomic abnormalities to idiopathic schizophrenia. These consistent cross-site findings highlight the homogeneity of this single genetic etiology, and support the suitability of 22q11DS as a biological model of schizophrenia.


Assuntos
Córtex Cerebral/patologia , Deleção Cromossômica , Síndrome de DiGeorge/genética , Síndrome de DiGeorge/patologia , Adolescente , Adulto , Feminino , Substância Cinzenta/patologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Transtornos Psicóticos/genética , Adulto Jovem
17.
Phys Rev Lett ; 124(16): 168002, 2020 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-32383904

RESUMO

We demonstrate experimentally that a granular packing of glass spheres is capable of storing memory of multiple strain states in the dynamic process of stress relaxation. Modeling the system as a noninteracting population of relaxing elements, we find that the functional form of the predicted relaxation requires a quantitative correction which grows in severity with each additional memory and is suggestive of interactions between elements. Our findings have implications for the broad class of soft matter systems that display memory and anomalous relaxation.

18.
Am J Med Genet A ; 182(3): 484-492, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31840928

RESUMO

The new 2017 diagnostic criteria for hypermobile Ehlers-Danlos Syndrome (hEDS) provide a framework for diagnosing hEDS but are more stringent than the previous Villefranche criteria. Our clinical experience at the GoodHope EDS clinic was that the 2017 criteria left many highly symptomatic patients without a diagnosis of hEDS. We conducted a retrospective cohort study to confirm our clinic experience and assess the accuracy of the 2017 diagnostic criteria for hEDS in patients who had a previous hEDS diagnosis based on the Villefranche criteria. Our study found that 15% (n = 20 of 131) of patients with a prior diagnosis of hEDS met the 2017 diagnostic criteria, and many of the traits used to distinguish hEDS were not significantly more frequent in patients who met 2017 criteria versus those who did not. In both groups objective systemic manifestations were found less frequently than subjective systemic manifestations. Beighton score (BS) as assessed by primary care practitioner was found to be higher than assessment by EDS practitioner in 81% (n = 74 of 91) of cases. Generalized joint hypermobility was confirmed in only 46% (n = 51 of 111) of patients who had a previous diagnosis of hEDS. Higher BS did not correlate with increased number of systemic manifestations in our cohort. Common comorbidities of hEDS were found with similar frequency in those who met 2017 criteria and those who did not. Based on our cohort, the 2017 hEDS diagnostic criteria require refinement to improve its diagnostic accuracy.


Assuntos
Síndrome de Ehlers-Danlos/diagnóstico , Síndrome de Ehlers-Danlos/genética , Instabilidade Articular/diagnóstico , Instabilidade Articular/genética , Adolescente , Adulto , Estudos de Coortes , Síndrome de Ehlers-Danlos/epidemiologia , Síndrome de Ehlers-Danlos/fisiopatologia , Feminino , Humanos , Instabilidade Articular/epidemiologia , Instabilidade Articular/fisiopatologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
19.
J Anim Ecol ; 89(11): 2692-2703, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32895913

RESUMO

Individual body size strongly influences the trophic role of marine organisms and the structure and function of marine ecosystems. Quantifying trophic position-individual body size relationships (trophic allometries) underpins the development of size-structured ecosystem models to predict abundance and the transfer of energy through ecosystems. Trophic allometries are well studied for fishes but remain relatively unexplored for cephalopods. Cephalopods are important components of coastal, oceanic and deep-sea ecosystems, and they play a key role in the transfer of biomass from low trophic positions to higher predators. It is therefore important to resolve cephalopod trophic allometries to accurately represent them within size-structured ecosystem models. We assessed the trophic positions of cephalopods in an oceanic pelagic (0-500 m) community (sampled by trawling in a cold-core eddy in the western Tasman Sea), comprising 22 species from 12 families, using bulk tissue stable isotope analysis and amino acid compound-specific stable isotope analysis. We assessed whether ontogenetic trophic position shifts were evident at the species-level and tested for the best predictor of community-level trophic allometry among body size, taxonomy and functional grouping (informed by fin and mantle morphology). Individuals in this cephalopod community spanned two trophic positions and fell into three functional groups on an activity level gradient: low, medium and high. The relationship between trophic position and ontogeny varied among species, with the most marked differences evident between species from different functional groups. Activity-level-based functional group and individual body size are best explained by cephalopod trophic positions (marginal R2  = 0.43). Our results suggest that the morphological traits used to infer activity level, such as fin-to-mantle length ratio, fin musculature and mantle musculature are strong predictors of cephalopod trophic allometries. Contrary to established theory, not all cephalopods are voracious predators. Low activity level cephalopods have a distinct feeding mode, with low trophic positions and little-to-no ontogenetic increases. Given the important role of cephalopods in marine ecosystems, distinct feeding modes could have important consequences for energy pathways and ecosystem structure and function. These findings will facilitate trait-based and other model estimates of cephalopod abundance in the changing global ocean.


Assuntos
Cefalópodes , Ecossistema , Animais , Organismos Aquáticos , Cadeia Alimentar , Estado Nutricional , Oceanos e Mares
20.
J Vasc Interv Radiol ; 30(5): 752-760, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30922796

RESUMO

PURPOSE: To evaluate the safety and efficacy of oxygen-ozone treatment delivered via a novel, handheld ozone-generating device for improving pain and function in herniated disc patients. MATERIALS AND METHODS: A total of 39 patients with contained herniated lumbar discs received oxygen-ozone treatment at 1 of 3 centers. Treatment consisted of injection of 2% ozone (10 mL): 3 mL delivered into the nucleus pulposus and 7 mL delivered into the adjacent paravertebral tissues. The first 8 patients received only ozone injections, whereas subsequent patients also received periganglionic methylprednisolone (40 mg) and 0.5% bupivacaine (1 mL) injections. Patients were evaluated at baseline and at 1 month, 6 months, and 12 months after treatment using the Oswestry Disability Index (ODI) and the Visual Analogue Scale (VAS) for leg pain and for back pain. Analgesic medication use was also assessed at each timepoint. RESULTS: Overall, 91% (32/35) of the per-protocol patients (those who completed follow-up and did not have significant protocol deviations) showed detectable improvement in ODI at 1-month follow-up; this increased to 93% (26/28) of patients at 12-months follow-up. At 1 month after treatment, 60% (21/35) of patients showed significant improvement in ODI scores (P = .01); 54% (19/35) showed significant improvement in VAS scores for leg pain (P = .05); and 49% (17/35) showed significant improvement in VAS scores for back pain (P = .12). At 6 months after treatment, 67% (22/33) of patients showed significant improvement in ODI scores (P = .02); 64% (21/33) showed significant improvement in VAS scores for leg pain (P = .01); and 52% (17/33) showed significant improvement in VAS scores for back pain (P = .12). At 12 months after treatment, 68% (19/28) of patients showed significant improvement in ODI scores (P < .01); 64% (18/28) showed significant improvement in VAS scores for leg pain (P < .01); and 61% (17/28) showed significant improvement in VAS scores for back pain (P = .09). Leg pain typically subsided more quickly than back pain. Use of analgesic medications also significantly decreased at all follow-up timepoints compared to baseline (P < .01). There were no adverse events or device-related issues. CONCLUSIONS: At 1, 6, and 12 months after treatment, patients experienced significant improvements in pain and function as well as significantly decreased use of analgesic medication. Taken together with the absence of adverse events at 1-year follow-up, these data suggest that oxygen-ozone treatment is a safe and effective therapy for contained herniated discs.


Assuntos
Analgésicos/administração & dosagem , Dor nas Costas/tratamento farmacológico , Deslocamento do Disco Intervertebral/tratamento farmacológico , Disco Intervertebral/efeitos dos fármacos , Vértebras Lombares/efeitos dos fármacos , Ozônio/administração & dosagem , Manejo da Dor/métodos , Adulto , Analgésicos/efeitos adversos , Dor nas Costas/diagnóstico , Dor nas Costas/fisiopatologia , Canadá , Avaliação da Deficiência , Feminino , Humanos , Injeções Intralesionais , Disco Intervertebral/diagnóstico por imagem , Disco Intervertebral/fisiopatologia , Deslocamento do Disco Intervertebral/diagnóstico , Deslocamento do Disco Intervertebral/fisiopatologia , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/fisiopatologia , Masculino , Pessoa de Meia-Idade , Ozônio/efeitos adversos , Manejo da Dor/efeitos adversos , Medição da Dor , Projetos Piloto , Recuperação de Função Fisiológica , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
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