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1.
Nat Neurosci ; 2022 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-35606419

RESUMO

A key aim in epidemiological neuroscience is identification of markers to assess brain health and monitor therapeutic interventions. Quantitative susceptibility mapping (QSM) is an emerging magnetic resonance imaging technique that measures tissue magnetic susceptibility and has been shown to detect pathological changes in tissue iron, myelin and calcification. We present an open resource of QSM-based imaging measures of multiple brain structures in 35,273 individuals from the UK Biobank prospective epidemiological study. We identify statistically significant associations of 251 phenotypes with magnetic susceptibility that include body iron, disease, diet and alcohol consumption. Genome-wide associations relate magnetic susceptibility to 76 replicating clusters of genetic variants with biological functions involving iron, calcium, myelin and extracellular matrix. These patterns of associations include relationships that are unique to QSM, in particular being complementary to T2* signal decay time measures. These new imaging phenotypes are being integrated into the core UK Biobank measures provided to researchers worldwide, creating the potential to discover new, non-invasive markers of brain health.

2.
PLoS One ; 17(4): e0267019, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35427383

RESUMO

Spaghetti meat (SM), woody breast (WB), and white striping (WS) are myopathies that affect the pectoral muscle of fast-growing broiler chickens. The prevalence and possible risk factors of these myopathies have been reported in other countries, but not yet in Canada. Thus, the objective of this study was to assess the prevalence and risk factors associated with these myopathies in a representative population of Canadian broilers. From May 2019 to March 2020, 250 random breast fillets from each of 37 flocks (total, 9,250) were obtained from two processing plants and assessed for the presence and severity of myopathies. Demographic data (e.g., sex and average live weight), environmental conditions during the grow-out period (e.g., temperature), and husbandry parameters (e.g., vaccination) were collected for each flock. Associations between these factors and the myopathies were tested using logistic regression analyses. The prevalence of SM, severe WB, and mild or moderate WS was 36.3% (95% CI: 35.3-37.3), 11.8% (95% CI: 11.2-12.5), and 96.0% (95% CI: 95.6-96.4), respectively. Most (85.1%) of the fillets showed multiple myopathies. Regression analyses showed that the odds of SM increased with live weight (OR = 1.30, 95% CI 1.01-1.69) and higher environmental temperature during the grow-out period (OR = 1.75, 95% CI 1.31-2.34). The odds of WB increased with live weight (OR = 1.23, 95% CI 1.03-1.47) and when flocks were not vaccinated against coccidia (OR = 1.86, 95% CI 1.51-2.29). This study documents for the first time a high prevalence of myopathies in Ontario broilers, and suggests that these lesions may have a significant economic impact on the Canadian poultry industry. Our results indicate that environmental conditions and husbandry are associated with the development of breast myopathies, in agreement with the current literature. Future studies are needed to determine how risk factors can promote the occurrence of these conditions, in order to implement possible mitigating strategies.


Assuntos
Doenças Musculares , Doenças das Aves Domésticas , Animais , Galinhas/fisiologia , Carne/análise , Doenças Musculares/epidemiologia , Doenças Musculares/etiologia , Doenças Musculares/veterinária , Ontário , Músculos Peitorais/patologia , Doenças das Aves Domésticas/patologia , Prevalência , Fatores de Risco
3.
Front Psychiatry ; 13: 762719, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35432035

RESUMO

Most women in the perinatal period face sleep issues, which can affect their mental health. Only a few studies have focused on sleep trajectories and depressive symptoms of women during the perinatal period in China. This study aims to explore the development trajectory of sleep quality by classifying pregnant women according to the changes in their sleep quality during pregnancy and postpartum and investigate the correlation between different sleep quality trajectory groups and depressive symptoms. The Pittsburgh Sleep Quality Index (PSQI) was used to assess the sleep quality, and the Edinburgh Postnatal Depression Scale (EPDS) was used to assess the symptoms of depression. Participants (n = 412) completed the assessment of sleep quality, depressive symptoms, and some sociodemographic and obstetric data at 36 weeks of gestation, 1 week after delivery, and 6 weeks after delivery. The group-based trajectory model (GBTM) was used to complete the trajectory classification, and logistic regression was used to analyze the predictive factors of postpartum depressive symptoms. Four different sleep quality trajectories were determined: "stable-good," "worsening," "improving," and "stable-poor" groups. The results demonstrate that poor sleep trajectories, social support and parenting experience during the perinatal period are related to postpartum depression. Screening for prenatal sleep problems is crucial for identifying the onset of perinatal depressive symptoms.

4.
Neuropsychiatr Dis Treat ; 18: 761-771, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35414744

RESUMO

Introduction: The COVID-19 is a highly contagious disease belonging to the family of coronaviruses which can affect a great deal of people shortly. As a devastating event in the world, many people suffer the PTSD from this severe disease. The aim of study is to explore the prevalence and severity of post-traumatic stress disorder (PTSD) symptoms, and discuss the possible factors among the general public in China after the COVID-19 epidemic outbreak. Methods: This is a cross-sectional study. We used the self-designed demographic questionnaire and the Posttraumatic Stress Checklist-Civilian Version (PCL-C) of Chinese version as our screening tools to investigate 4872 subjects living in the communities in China from Nov. 8th, 2020 to Dec. 8th, 2020. Results: Finally, we received 3705 effective respondents. The response rates of the questionnaire can reach 76.97 percentage. Peculiarly, the prevalence of PTSD mild and severe symptoms after the COVID-19 epidemic outbreak was 53.2%. Mild PTSD symptoms accounted for 24.9%, and severe PTSD symptoms (scores above 38) accounted for 28.3%. PCL-C mean scores were 41.4±14.7. The females accounted for 67.7% of the total samples. Participants' mean age was 30.5±11.2 years old. The PCL-C gross scores of females were all higher than males in four subject groups. Meantime, gender and age made differences not only in total PCL-C points but also in the four aspects of PCL-C (P<0.001). The middle-aged group (ages from 45 to 60) got the lowest scores among the four groups. Conclusion: COVID-19 brought tremendous psychological pressure on the public in many ways, including people's work, social contact, study, and daily life. Results of our research discover that symptoms of the PTSD are severe, including the re-experiencing, avoidance/numbing, flashbacks, and hyper-arousal. Actions should be taken at society level to prevent and protect individuals from PTSD suffering. Special attention should be paid to females and young people. Further studies should be conducted to explore the dynamic and other risk and protection factors to prevent PTSD.

5.
iScience ; 25(4): 104111, 2022 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-35402887

RESUMO

We report a combined experimental and theoretical study on intriguing magnetic properties of quasiferroelectric orthochromates. Large single crystals of the family of RECrO3 (RE = Y, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu) compounds were successfully grown. Neutron Laue study indicates a good quality of the obtained single crystals. Applied magnetic field and temperature dependent magnetization measurements reveal their intrinsic magnetic properties, especially the antiferromagnetic (AFM) transition temperatures. Density functional theory studies of the electronic structures were carried out using the Perdew-Burke-Ernzerhof functional plus Hubbard U method. Crystallographic information and magnetism were theoretically optimized systematically. When RE3+ cations vary from Y3+ and Eu3+ to Lu3+ ions, the calculated t-e orbital hybridization degree and Néel temperature behave similarly to the experimentally determined AFM transition temperature with variation in cationic radius. We found that the t-e hybridization is anisotropic, causing a magnetic anisotropy of Cr3+ sublattices. This was evaluated with the nearest-neighbor J 1-J 2 model. Our research provides a picture of the electronic structures during the t-e hybridization process while changing RE ions and sheds light on the nature of the weak ferromagnetism coexisting with predominated antiferromagnetism. The available large RECrO3 single crystals build a platform for further studies of orthochromates.

6.
Elife ; 112022 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-35297760

RESUMO

Post-mortem magnetic resonance imaging (MRI) provides the opportunity to acquire high-resolution datasets to investigate neuroanatomy and validate the origins of image contrast through microscopy comparisons. We introduce the Digital Brain Bank (open.win.ox.ac.uk/DigitalBrainBank), a data release platform providing open access to curated, multimodal post-mortem neuroimaging datasets. Datasets span three themes-Digital Neuroanatomist: datasets for detailed neuroanatomical investigations; Digital Brain Zoo: datasets for comparative neuroanatomy; and Digital Pathologist: datasets for neuropathology investigations. The first Digital Brain Bank data release includes 21 distinctive whole-brain diffusion MRI datasets for structural connectivity investigations, alongside microscopy and complementary MRI modalities. This includes one of the highest-resolution whole-brain human diffusion MRI datasets ever acquired, whole-brain diffusion MRI in fourteen nonhuman primate species, and one of the largest post-mortem whole-brain cohort imaging studies in neurodegeneration. The Digital Brain Bank is the culmination of our lab's investment into post-mortem MRI methodology and MRI-microscopy analysis techniques. This manuscript provides a detailed overview of our work with post-mortem imaging to date, including the development of diffusion MRI methods to image large post-mortem samples, including whole, human brains. Taken together, the Digital Brain Bank provides cross-scale, cross-species datasets facilitating the incorporation of post-mortem data into neuroimaging studies.


Assuntos
Acesso à Informação , Encéfalo , Animais , Autopsia , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Humanos , Imageamento por Ressonância Magnética , Neuroimagem
7.
Poult Sci ; 101(4): 101747, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35245806

RESUMO

Spaghetti meat (SM), woody breast (WB), and white striping (WS) are myopathies affecting breast muscle of broiler chickens, and are characterized by a loss of myofibers and an increase in fibrous tissue. The conditions develop in intensive broiler chicken production systems, and cause poor meat process-ability and negative customer perception leading to monetary losses. The objectives of the present study were to describe the physical and histological characteristics of breast myopathies from commercial broiler chicken flocks in Ontario, Canada, and to assess the associations between the severity of myopathies with the physical and histological characteristics of the affected breast muscle fillets. Chicken breast fillets (n = 179) were collected over 3 visits from a processing plant and scored macroscopically to assess the severity of myopathies, following an established scoring scheme. For each fillet, the surface area, length, width, thickness, weight, and hardness (compression force) were measured. A subset of 60 fillets was evaluated microscopically. Multinomial logistic regression models were built to evaluate associations between physical parameters and macroscopic scores. The odds of SM co-occurring with severe WB (SM1WB2) were significantly associated with increased fillet thickness (OR = 1.59, 95% CI 1.31-1.94) and weight (OR = 1.06, 95% CI 1.03-1.09). Histologically, myopathies had overlapping lesions consisting of polyphasic myodegeneration, perivascular inflammatory cuffing and accumulation of fibrous tissue and fat. The pairwise correlation between macroscopic and microscopic scores was moderate (rho 0.45, P < 0.001). This is the first study to characterize breast myopathies in Canadian broiler flocks. Results show that the morphologic and microscopic changes of fillets from this cohort are similar to data from other countries, and provide database to benchmark these parameters in future studies. Our standardized categorization can be applied to broiler breast fillets in other regions of the world.


Assuntos
Doenças Musculares , Doenças das Aves Domésticas , Animais , Galinhas , Humanos , Carne/análise , Doenças Musculares/epidemiologia , Doenças Musculares/etiologia , Doenças Musculares/veterinária , Ontário/epidemiologia , Músculos Peitorais/fisiologia , Doenças das Aves Domésticas/patologia
8.
Nature ; 604(7907): 697-707, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35255491

RESUMO

There is strong evidence of brain-related abnormalities in COVID-191-13. However, it remains unknown whether the impact of SARS-CoV-2 infection can be detected in milder cases, and whether this can reveal possible mechanisms contributing to brain pathology. Here we investigated brain changes in 785 participants of UK Biobank (aged 51-81 years) who were imaged twice using magnetic resonance imaging, including 401 cases who tested positive for infection with SARS-CoV-2 between their two scans-with 141 days on average separating their diagnosis and the second scan-as well as 384 controls. The availability of pre-infection imaging data reduces the likelihood of pre-existing risk factors being misinterpreted as disease effects. We identified significant longitudinal effects when comparing the two groups, including (1) a greater reduction in grey matter thickness and tissue contrast in the orbitofrontal cortex and parahippocampal gyrus; (2) greater changes in markers of tissue damage in regions that are functionally connected to the primary olfactory cortex; and (3) a greater reduction in global brain size in the SARS-CoV-2 cases. The participants who were infected with SARS-CoV-2 also showed on average a greater cognitive decline between the two time points. Importantly, these imaging and cognitive longitudinal effects were still observed after excluding the 15 patients who had been hospitalised. These mainly limbic brain imaging results may be the in vivo hallmarks of a degenerative spread of the disease through olfactory pathways, of neuroinflammatory events, or of the loss of sensory input due to anosmia. Whether this deleterious effect can be partially reversed, or whether these effects will persist in the long term, remains to be investigated with additional follow-up.


Assuntos
Encéfalo , COVID-19 , Idoso , Idoso de 80 Anos ou mais , Bancos de Espécimes Biológicos , Encéfalo/diagnóstico por imagem , Encéfalo/virologia , COVID-19/patologia , Humanos , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , SARS-CoV-2 , Olfato , Reino Unido/epidemiologia
9.
Artigo em Inglês | MEDLINE | ID: mdl-35254999

RESUMO

Susceptibility weighted imaging (SWI) is a routine magnetic resonance imaging (MRI) sequence that combines the magnitude and high-pass filtered phase images to qualitatively enhance the image contrasts related to tissue susceptibility. Tremendous amounts of the high-pass filtered phase data with low signal to noise ratio and incomplete background field removal have thus been collected under default clinical settings. Since SWI cannot quantitatively estimate the susceptibility, it is thus non-trivial to derive quantitative susceptibility mapping (QSM) directly from these redundant phase data, which effectively promotes the mining of the SWI data collected previously and even provides potentials for synchronous imaging of both SWI and QSM based on single SWI scanning in future. To this end, a novel deep learning based SWI-to-QSM-Net (S2Q-Net) is proposed for QSM reconstruction from SWI high-pass filtered phase data. S2Q-Net firstly estimates the edge maps of QSM to integrate edge prior into features, which benefits the network to reconstruct QSM with realistic and clear tissue boundaries. Furthermore, a novel Second-order Cross Dense Block is proposed in S2Q-Net, which can capture rich inter-region interactions to provide rich non-local phase information related to local tissue susceptibility. Experimental results on both simulated and in-vivo datasets demonstrate its superiority over all the compared QSM reconstruction methods, including conventional methods and the state-of-the-art DL-based algorithms. Our results suggest the potentials of S2Q-Net to reconstruct promising QSM from the high-pass filtered phase obtained in clinical SWI sequences.

10.
Materials (Basel) ; 15(6)2022 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-35329505

RESUMO

To obtain a deeper understand of the energy transfer mechanism between Ce3+ and Tb3+ ions in the aluminum garnet hosts, (Ce, Tb, Gd)3Ga2Al3O12 (GGAG:Ce, Tb) single crystals grown by the optical floating zone (OFZ) method were investigated systematically in a wide range of Tb3+ doping concentration (1-66 at.%). Among those, crystal with 7 at.% Tb reached a single garnet phase while the crystals with other Tb3+ concentrations are mixed phases of garnet and perovskite. Obvious Ce and Ga loss can be observed by an energy dispersive X-ray spectroscope (EDS) technology. The absorption bands belonging to both Ce3+ and Tb3+ ions can be observed in all crystals. Photoluminescence (PL) spectra show the presence of an efficient energy transfer from the Tb3+ to Ce3+ and the gradually quenching effect with increasing of Tb3+ concentration. GGAG: 1% Ce3+, 7% Tb3+ crystal was found to possess the highest PL intensity under excitation of 450 nm. The maximum light yield (LY) reaches 18,941 pho/MeV. The improved luminescent and scintillation characteristics indicate that the cation engineering of Tb3+ can optimize the photoconversion performance of GGAG:Ce.

11.
Hum Brain Mapp ; 43(2): 760-772, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-34676625

RESUMO

Structural magnetic resonance imaging (sMRI) can capture the spatial patterns of brain atrophy in Alzheimer's disease (AD) and incipient dementia. Recently, many sMRI-based deep learning methods have been developed for AD diagnosis. Some of these methods utilize neural networks to extract high-level representations on the basis of handcrafted features, while others attempt to learn useful features from brain regions proposed by a separate module. However, these methods require considerable manual engineering. Their stepwise training procedures would introduce cascading errors. Here, we propose the parallel attention-augmented bilinear network, a novel deep learning framework for AD diagnosis. Based on a 3D convolutional neural network, the framework directly learns both global and local features from sMRI scans without any prior knowledge. The framework is lightweight and suitable for end-to-end training. We evaluate the framework on two public datasets (ADNI-1 and ADNI-2) containing 1,340 subjects. On both the AD classification and mild cognitive impairment conversion prediction tasks, our framework achieves competitive results. Furthermore, we generate heat maps that highlight discriminative areas for visual interpretation. Experiments demonstrate the effectiveness of the proposed framework when medical priors are unavailable or the computing resources are limited. The proposed framework is general for 3D medical image analysis with both efficiency and interpretability.


Assuntos
Doença de Alzheimer/diagnóstico por imagem , Córtex Cerebral/diagnóstico por imagem , Disfunção Cognitiva/diagnóstico por imagem , Aprendizado Profundo , Progressão da Doença , Imageamento por Ressonância Magnética/métodos , Neuroimagem/métodos , Idoso , Humanos , Prognóstico
12.
medRxiv ; 2022 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-34189535

RESUMO

There is strong evidence for brain-related abnormalities in COVID-19 1-13 . It remains unknown however whether the impact of SARS-CoV-2 infection can be detected in milder cases, and whether this can reveal possible mechanisms contributing to brain pathology. Here, we investigated brain changes in 785 UK Biobank participants (aged 51-81) imaged twice, including 401 cases who tested positive for infection with SARS-CoV-2 between their two scans, with 141 days on average separating their diagnosis and second scan, and 384 controls. The availability of pre-infection imaging data reduces the likelihood of pre-existing risk factors being misinterpreted as disease effects. We identified significant longitudinal effects when comparing the two groups, including: (i) greater reduction in grey matter thickness and tissue-contrast in the orbitofrontal cortex and parahippocampal gyrus, (ii) greater changes in markers of tissue damage in regions functionally-connected to the primary olfactory cortex, and (iii) greater reduction in global brain size. The infected participants also showed on average larger cognitive decline between the two timepoints. Importantly, these imaging and cognitive longitudinal effects were still seen after excluding the 15 cases who had been hospitalised. These mainly limbic brain imaging results may be the in vivo hallmarks of a degenerative spread of the disease via olfactory pathways, of neuroinflammatory events, or of the loss of sensory input due to anosmia. Whether this deleterious impact can be partially reversed, or whether these effects will persist in the long term, remains to be investigated with additional follow up.

13.
Front Nutr ; 9: 799053, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35369066

RESUMO

Metabolites of probiotics that are beneficial to human health have been isolated from the intestinal tract and natural dairy products. However, many studies on probiotics and prebiotics are limited to the observation of human cohorts and animal phenotypes. The molecular mechanisms by which metabolites of probiotics regulate health are still need further exploration. In this work, we isolated a strain of Lactobacillus Paracasei from human milk samples. We numbered it as Lactobacillus Paracasei BD5115. The mouse model of high-fat diet confirmed that the metabolites of this strain also promotes intestinal epithelial cells (IECs) proliferation. Single-cell sequencing showed that a bZIP transcription factor MAFF was specifically expressed in some IECs. We found that MAFF interacted with MBP1 to regulate the expression of MYC. Analysis of the active components in BD5115 metabolites confirmed that 2-hydroxy-3-methylbutyric acid promotes the expression of the MYC gene. This promotes the proliferation of IECs. Our findings indicate that 2-hydroxy-3-methylbutyric acid regulate MYC gene expression mediated by MAFF/MBP1 interaction. This study not only screened a strain with promoted IECs proliferation, but also discovered a new signal pathway that regulates MYC gene expression.

14.
PLoS Negl Trop Dis ; 15(12): e0010025, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34919557

RESUMO

Pneumocystis pneumonia (PCP) and pulmonary toxoplasmosis (PT) are caused by Pneumocystis jirovecii and Toxoplasma gondii. The clinical symptoms and imaging of PCP and PT are indistinguishable. A duplex qPCR was developed to differentiate between these two pathogens. In testing 92 clinical samples to validate the performance of this method for P. jirovecii detection, it identified 31 positive samples for P. jirovecii infection, consistent with clinical diagnosis. Among the remainder of the 61 clinical samples with suspected PCP, yet showing as negative by the conventional PCR diagnosis approach, 6 of them proved positive using our new assay. Our new approach also produced similar results in identification of T. gondii infections, giving a result of 2 positive and 20 negative in clinical samples. An investigation was undertaken on the prevalence of P. jirovecii and T. gondii infections using 113 samples from lung infection patients. 9% (10/113) were shown to be positive with infections of P. jirovecii, 2% with T. gondii (2/113) and 5% (6/113) were co-infected with both pathogens. Although this duplex qPCR can detect individual P. jirovecii and T. gondii infection, and co-infection of both pathogens, further large-scale investigations are needed to validate its performance, especially in T. gondii detection. Our assay provides a rapid and accurate tool for PCP and PT diagnosis in immunocompromised population and clinical surveillance of these infections in patients with no immune defects.


Assuntos
Pneumopatias/microbiologia , Pneumopatias/parasitologia , Pneumocystis carinii/isolamento & purificação , Pneumonia por Pneumocystis/microbiologia , Reação em Cadeia da Polimerase/métodos , Toxoplasma/isolamento & purificação , Toxoplasmose/parasitologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Feminino , Humanos , Hospedeiro Imunocomprometido , Lactente , Pulmão/microbiologia , Pulmão/parasitologia , Pneumopatias/diagnóstico , Masculino , Pessoa de Meia-Idade , Pneumocystis carinii/genética , Pneumonia por Pneumocystis/diagnóstico , Toxoplasma/genética , Toxoplasmose/diagnóstico , Adulto Jovem
15.
Front Neurol ; 12: 753284, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34777224

RESUMO

SARS-CoV-2 infection has been shown to damage multiple organs, including the brain. Multiorgan MRI can provide further insight on the repercussions of COVID-19 on organ health but requires a balance between richness and quality of data acquisition and total scan duration. We adapted the UK Biobank brain MRI protocol to produce high-quality images while being suitable as part of a post-COVID-19 multiorgan MRI exam. The analysis pipeline, also adapted from UK Biobank, includes new imaging-derived phenotypes (IDPs) designed to assess the possible effects of COVID-19. A first application of the protocol and pipeline was performed in 51 COVID-19 patients post-hospital discharge and 25 controls participating in the Oxford C-MORE study. The protocol acquires high resolution T1, T2-FLAIR, diffusion weighted images, susceptibility weighted images, and arterial spin labelling data in 17 min. The automated imaging pipeline derives 1,575 IDPs, assessing brain anatomy (including olfactory bulb volume and intensity) and tissue perfusion, hyperintensities, diffusivity, and susceptibility. In the C-MORE data, IDPs related to atrophy, small vessel disease and olfactory bulbs were consistent with clinical radiology reports. Our exploratory analysis tentatively revealed some group differences between recovered COVID-19 patients and controls, across severity groups, but not across anosmia groups. Follow-up imaging in the C-MORE study is currently ongoing, and this protocol is now being used in other large-scale studies. The protocol, pipeline code and data are openly available and will further contribute to the understanding of the medium to long-term effects of COVID-19.

16.
Neuroimage ; 244: 118586, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34563678

RESUMO

Mild cognitive impairment (MCI) conversion prediction, i.e., identifying MCI patients of high risks converting to Alzheimer's disease (AD), is essential for preventing or slowing the progression of AD. Although previous studies have shown that the fusion of multi-modal data can effectively improve the prediction accuracy, their applications are largely restricted by the limited availability or high cost of multi-modal data. Building an effective prediction model using only magnetic resonance imaging (MRI) remains a challenging research topic. In this work, we propose a multi-modal multi-instance distillation scheme, which aims to distill the knowledge learned from multi-modal data to an MRI-based network for MCI conversion prediction. In contrast to existing distillation algorithms, the proposed multi-instance probabilities demonstrate a superior capability of representing the complicated atrophy distributions, and can guide the MRI-based network to better explore the input MRI. To our best knowledge, this is the first study that attempts to improve an MRI-based prediction model by leveraging extra supervision distilled from multi-modal information. Experiments demonstrate the advantage of our framework, suggesting its potentials in the data-limited clinical settings.


Assuntos
Doença de Alzheimer/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Atrofia , Encéfalo/patologia , Disfunção Cognitiva/diagnóstico por imagem , Feminino , Humanos , Conhecimento , Aprendizagem , Masculino , Pessoa de Meia-Idade , Probabilidade
17.
Artigo em Inglês | MEDLINE | ID: mdl-34582347

RESUMO

Motion blur in dynamic scenes is an important yet challenging research topic. Recently, deep learning methods have achieved impressive performance for dynamic scene deblurring. However, the motion information contained in a blurry image has yet to be fully explored and accurately formulated because: (i) the ground truth of dynamic motion is difficult to obtain; (ii) the temporal ordering is destroyed during the exposure; and (iii) the motion estimation from a blurry image is highly ill-posed. By revisiting the principle of camera exposure, motion blur can be described by the relative motions of sharp content with respect to each exposed position. In this paper, we define exposure trajectories, which represent the motion information contained in a blurry image and explain the causes of motion blur. A novel motion offset estimation framework is proposed to model pixel-wise displacements of the latent sharp image at multiple timepoints. Under mild constraints, our method can recover dense, (non-)linear exposure trajectories, which significantly reduce temporal disorder and ill-posed problems. Finally, experiments demonstrate that the recovered exposure trajectories not only capture accurate and interpretable motion information from a blurry image, but also benefit motion-aware image deblurring and warping-based video extraction tasks. Codes are available on https://github.com/yjzhang96/Motion-ETR.

18.
Vaccines (Basel) ; 9(7)2021 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-34358207

RESUMO

The potential of Eimeria parasites as live vaccine vectors has been reported with successful genetic manipulation on several species like E. tenella, E. mitis and E. necatrix. Among seven Eimeria species infecting chickens, E. acervulina is a highly prevalent, moderately pathogenic species. Thus, it is valuable for the study of transfection and for use as a potential as vaccine vector. In this study, a plasmid containing expression cassette with enhanced yellow fluorescent protein (EYFP), red fluorescent protein (RFP) and 12 copies of extracellular domain of H9N2 avian influenza virus M2 (M2e) protein was used for the transfection. Nucleofected sporozoites were inoculated into birds through wing vein. Recombinant E. acervulina oocysts with 0.1% EYFP+ and RFP+ populations were collected from the feces of the inoculated birds. The fluorescent rate of transgenic parasites reached over 95% after nine successive propagations with a pyrimethamine selection in vivo and fluorescent-activated cell sorting (FACS) of progeny oocysts. The expression of M2e in the transgenic parasites (EaM2e) was confirmed by Western blot and its cytoplasm localization in sporozoites was displayed by an indirect immunofluorescent assay (IFA). Meanwhile, we found that the fecundity of EaM2e was equivalent to that of wild type E. acervulina (EaWT). Taken together, the stable transfection of E. acervulina was successfully established. Future studies will focus on whether transgenic E. acervulina can serve as a live vaccine vector.

19.
Zhongguo Zhong Yao Za Zhi ; 46(8): 2061-2066, 2021 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-33982520

RESUMO

In the pharmacopoeia, many process parameters for the purification process of Scutellariae Radix are unclear. In this study, deterministic screening design combined with design space method was used to optimize the purification process of Scutellariae Radix extract. Nine method parameters such as mass fraction of solution(X_1), first acid precipitation pH(X_2) and first holding time(X_3) in the purification process were firstly studied by definitive screening design. The yield of baicalin was defined as the evaluation index. A stepwise regression method was used then to build quantitative models between evaluation index and method parameters and the three most critical impact parameters were determined. Probability-based design space was calculated and successfully verified with the experimental error simulation method. Finally, the second standing temperature, the first standing temperature and the pH value of the second acid precipitation were determined as the three most critical method parameters. The recommended operating space was as follows: the second standing temperature 5-7 ℃, the first standing temperature 13-15 ℃, and the pH of the second acid precipitation 1.5-1.7. Within this operating space, the baicalin yield in the purification process was over 80%, and the probability of reaching the standard was over 0.96. In this study, we optimized the effect of various parameters for the purification process of the Scutellariae Radix extract in the pharmacopoeia on the yield of baicalin and provided a reference for industrial production of the exact of Scutellariae Radix.


Assuntos
Medicamentos de Ervas Chinesas , Scutellaria baicalensis , Flavonoides , Extratos Vegetais
20.
J Chromatogr A ; 1646: 462066, 2021 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-33845265

RESUMO

Maslinic acid and corosolic acid with high purity were successfully separated from Eriobotrya japonica (Thunb.) leaves by two-step countercurrent chromatographic separation. Two biphasic solvent systems composed of petroleum ether-ethyl acetate-ethanol-water (6:4:5:5, v/v) and petroleum ether-ethyl acetate-ethanol-0.10 mol/L of hydroxypropyl-ß-cyclodextrin with pH 7.0 (8:2:3.5:6.5, v/v) were selected according to the partition performance of the main structural isomeric pentacyclic triterpenes. The influences of pH value and concentration of hydroxypropyl-ß-cyclodextrin in separation of two isomers were investigated. In first step countercurrent chromatographic separation, a mixture of two target structural isomers (14.12 mg of sample I) was separated from 40.00 mg of a partially purified sample. In second step countercurrent chromatographic separation, maslinic acid and corosolic acid were completely isolated from 12.00 mg of sample I with hydroxypropyl-ß-cyclodextrin as aqueous phase additive. The recoveries of the two isomers were over 90%, yielding 5.18 mg of maslinic acid and 5.47 mg of corosolic acid, respectively.


Assuntos
2-Hidroxipropil-beta-Ciclodextrina/química , Distribuição Contracorrente/métodos , Eriobotrya/química , Triterpenos Pentacíclicos/isolamento & purificação , Folhas de Planta/química , Cromatografia Líquida de Alta Pressão/métodos , Triterpenos Pentacíclicos/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Estereoisomerismo
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