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1.
Cerebellum ; 22(2): 249-260, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35286708

RESUMO

The cerebellum is ontogenetically one of the first structures to develop in the central nervous system; nevertheless, it has been only recently reconsidered for its significant neurobiological, functional, and clinical relevance in humans. Thus, it has been a relatively under-studied compared to the cerebrum. Currently, non-invasive imaging modalities can barely reach the necessary resolution to unfold its entire, convoluted surface, while only histological analyses can reveal local information at the micrometer scale. Herein, we used the BigBrain dataset to generate area and point-wise thickness measurements for all layers of the cerebellar cortex and for each lobule in particular. We found that the overall surface area of the cerebellar granular layer (including Purkinje cells) was 1,732 cm2 and the molecular layer was 1,945 cm2. The average thickness of the granular layer is 0.88 mm (± 0.83) and that of the molecular layer is 0.32 mm (± 0.08). The cerebellum (both granular and molecular layers) is thicker at the depth of the sulci and thinner at the crowns of the gyri. Globally, the granular layer is thicker in the lateral-posterior-inferior region than the medial-superior regions. The characterization of individual layers in the cerebellum achieved herein represents a stepping-stone for investigations interrelating structural and functional connectivity with cerebellar architectonics using neuroimaging, which is a matter of considerable relevance in basic and clinical neuroscience. Furthermore, these data provide templates for the construction of cerebellar topographic maps and the precise localization of structural and functional alterations in diseases affecting the cerebellum.


Assuntos
Córtex Cerebelar , Cerebelo , Humanos , Córtex Cerebelar/patologia , Cerebelo/fisiologia , Células de Purkinje
2.
J Biomed Inform ; 143: 104393, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37209975

RESUMO

OBJECTIVE: Acute kidney injury (AKI), a common condition on the intensive-care unit (ICU), is characterized by an abrupt decrease in kidney function within a few hours or days, leading to kidney failure or damage. Although AKI is associated with poor outcomes, current guidelines overlook the heterogeneity among patients with this condition. Identification of AKI subphenotypes could enable targeted interventions and a deeper understanding of the injury's pathophysiology. While previous approaches based on unsupervised representation learning have been used to identify AKI subphenotypes, these methods cannot assess time series or disease severity. METHODS: In this study, we developed a data- and outcome-driven deep-learning (DL) approach to identify and analyze AKI subphenotypes with prognostic and therapeutic implications. Specifically, we developed a supervised long short-term memory (LSTM) autoencoder (AE) with the aim of extracting representation from time-series EHR data that were intricately correlated with mortality. Then, subphenotypes were identified via application of K-means. RESULTS: In two publicly available datasets, three distinct clusters were identified, characterized by mortality rates of 11.3%, 17.3%, and 96.2% in one dataset and 4.6%, 12.1%, and 54.6% in the other. Further analysis demonstrated that AKI subphenotypes identified by our proposed approach were statistically significant on several clinical characteristics and outcomes. CONCLUSION: In this study, our proposed approach could successfully cluster the AKI population in ICU settings into 3 distinct subphenotypes. Thus, such approach could potentially improve outcomes of AKI patients in the ICU, with better risk assessment and potentially better personalized treatment.


Assuntos
Injúria Renal Aguda , Aprendizado Profundo , Humanos , Prognóstico , Unidades de Terapia Intensiva , Medição de Risco , Injúria Renal Aguda/diagnóstico , Injúria Renal Aguda/epidemiologia , Estudos Retrospectivos
3.
Sensors (Basel) ; 23(3)2023 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-36772473

RESUMO

The expression abundance of transcripts in nondiseased breast tissue varies among individuals. The association study of genotypes and imaging phenotypes may help us to understand this individual variation. Since existing reports mainly focus on tumors or lesion areas, the heterogeneity of pathological image features and their correlations with RNA expression profiles for nondiseased tissue are not clear. The aim of this study is to discover the association between the nucleus features and the transcriptome-wide RNAs. We analyzed both microscopic histology images and RNA-sequencing data of 456 breast tissues from the Genotype-Tissue Expression (GTEx) project and constructed an automatic computational framework. We classified all samples into four clusters based on their nucleus morphological features and discovered feature-specific gene sets. The biological pathway analysis was performed on each gene set. The proposed framework evaluates the morphological characteristics of the cell nucleus quantitatively and identifies the associated genes. We found image features that capture population variation in breast tissue associated with RNA expressions, suggesting that the variation in expression pattern affects population variation in the morphological traits of breast tissue. This study provides a comprehensive transcriptome-wide view of imaging-feature-specific RNA expression for healthy breast tissue. Such a framework could also be used for understanding the connection between RNA expression and morphology in other tissues and organs. Pathway analysis indicated that the gene sets we identified were involved in specific biological processes, such as immune processes.


Assuntos
Neoplasias da Mama , Transcriptoma , Humanos , Feminino , Transcriptoma/genética , RNA/genética , Análise de Sequência de RNA , Genótipo , Fenótipo , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/genética
4.
J Dairy Sci ; 105(6): 4903-4914, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35346470

RESUMO

Goat milk whey protein concentrates were manufactured by microfiltration (MF) and ultrafiltration (UF). When MF retentate blended with cream, which could be used as a starting material in yogurt making. The objective of this study was to prepare goat milk whey protein concentrates by membrane separation technology and to investigate the effects of polymerized goat milk whey protein (PGWP) on the physicochemical properties and microstructure of recombined goat milk yogurt. A 3-stage MF study was conducted to separate whey protein from casein in skim milk with 0.1-µm ceramic membrane. The MF permeate was ultrafiltered using a 10 kDa cut-off membrane to 10-fold, followed by 3 step diafiltration. The ultrafiltration-diafiltration-treated whey was electrodialyzed to remove 85% of salt, and to obtain goat milk whey protein concentrates with 80.99% protein content (wt/wt, dry basis). Recombined goat milk yogurt was prepared by mixing cream and MF retentate, and PGWP was used as main thickening agent. Compared with the recombined goat milk yogurt without PGWP, the yogurt with 0.50% PGWP had desirable viscosity and low level of syneresis. There was no significant difference in chemical composition and pH between the recombined goat milk yogurt with PGWP and control (without PGWP). Viscosity of all the yogurt samples decreased during the study. There was a slight but not significant decrease in pH during storage. Bifidobacterium and Lactobacillus acidophilus in yogurt samples remained above 106 cfu/g during 8-wk storage. Scanning electron microscopy of the recombined goat milk yogurt with PGWP displayed a compact protein network. Results indicated that PGWP prepared directly from raw milk may be a novel protein-based thickening agent for authentic goat milk yogurt making.


Assuntos
Leite , Iogurte , Animais , Cabras , Leite/química , Proteínas do Leite/análise , Soro do Leite/química , Proteínas do Soro do Leite/química , Iogurte/microbiologia
5.
Angew Chem Int Ed Engl ; 60(35): 19079-19084, 2021 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-34187100

RESUMO

Controlling the chemo- and regioselectivity of transition-metal-catalyzed C-C activation remains a great challenge. The transformations of benzocyclobutenones (BCBs) usually involve the cleavage of C1-C2 bond. In this work, an unprecedented highly selective cleavage of C1-C8 bond with the insertion of alkynes is achieved by using blocking strategy via Ni catalysis, providing an efficient method for synthesis of 1,8-disubstituted naphthalenes. Notably, the blocking group could be readily removed after the transformation.

7.
J Neurosci ; 37(18): 4661-4678, 2017 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-28373391

RESUMO

The continuous addition of new dentate granule cells (DGCs), which is regulated exquisitely by brain activity, renders the hippocampus plastic. However, how neural circuits encode experiences to affect the addition of adult-born neurons remains unknown. Here, we used endoscopic Ca2+ imaging to track the real-time activity of individual DGCs in freely behaving mice. For the first time, we found that active DGCs responded to a novel experience by increasing their Ca2+ event frequency preferentially. This elevated activity, which we found to be associated with object exploration, returned to baseline by 1 h in the same environment, but could be dishabituated via introduction to a novel environment. To transition seamlessly between environments, we next established a freely controllable virtual reality system for unrestrained mice. We again observed increased firing of active neurons in a virtual enriched environment. Interestingly, multiple novel virtual experiences increased the number of newborn neurons accumulatively compared with a single experience. Finally, optogenetic silencing of existing DGCs during novel environmental exploration perturbed experience-induced neuronal addition. Our study shows that the adult brain conveys novel, enriched experiences to increase the addition of adult-born hippocampal neurons by increasing the firing of active DGCs.SIGNIFICANCE STATEMENT Adult brains are constantly reshaping themselves from synapses to circuits as we encounter novel experiences from moment to moment. Importantly, this reshaping includes the addition of newborn hippocampal neurons. However, it remains largely unknown how our circuits encode experience-induced brain activity to govern the addition of new hippocampal neurons. By coupling in vivo Ca2+ imaging of dentate granule neurons with a novel, unrestrained virtual reality system for rodents, we discovered that a new experience increased firing of active dentate granule neurons rapidly and robustly. Exploration in multiple novel virtual environments, compared with a single environment, promoted dentate activation and enhanced the addition of new hippocampal neurons accumulatively. Finally, silencing this activation optogenetically during novel experiences perturbed experience-induced neuronal addition.


Assuntos
Potenciais de Ação/fisiologia , Giro Denteado/fisiologia , Hipocampo/fisiologia , Memória/fisiologia , Neurogênese/fisiologia , Neurônios/fisiologia , Animais , Sinalização do Cálcio/fisiologia , Giro Denteado/citologia , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Rede Nervosa/fisiologia , Plasticidade Neuronal/fisiologia , Neurônios/citologia , Aprendizagem Baseada em Problemas
8.
Epidemiology ; 29(5): 675-683, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29847497

RESUMO

BACKGROUND: Norovirus is a leading cause of outbreaks of acute infectious gastroenteritis worldwide, yet its transmissibility within households and associated risk factors remain unknown in developing countries. METHODS: Household, demographic, and clinical data were collected from a semi-urban area in south China where an outbreak occurred in the winter of 2014. Using a Bayesian modeling framework, we assessed the transmissibility and potential risk modifiers in both urban and rural households. RESULTS: In urban apartment buildings, the secondary attack rates were 84% (95% credible interval [CI] = 60%, 96%) among households of size two and 29% (95% CI = 9.6%, 53%) in larger households. In the rural village, secondary attack rate estimates were lower than the urban setting, 13% (0.51%, 54%) for households of size two and 7.3% (0.38%, 27%) for larger households. Males were 31% (95% CI = 3%, 50%) less susceptible to the disease than female. Water disinfection with chlorine was estimated to reduce environmental risk of infection by 60% (95% CI = 26%, 82%), and case isolation was estimated to reduce person-to-person transmission by 65% (95% CI = 15%, 93%). Nausea and vomiting were not associated with household transmission. CONCLUSIONS: Norovirus is highly contagious within households, in particular in small households in urban communities. Our results suggest that water disinfection and case isolation are associated with reduction of outbreaks in resource-limited communities.


Assuntos
Infecções por Caliciviridae/transmissão , Surtos de Doenças/estatística & dados numéricos , Norovirus , População Rural/estatística & dados numéricos , População Urbana/estatística & dados numéricos , Adulto , Fatores Etários , Teorema de Bayes , Infecções por Caliciviridae/epidemiologia , China/epidemiologia , Características da Família , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Fatores Sexuais , Adulto Jovem
9.
Int J Syst Evol Microbiol ; 65(Pt 3): 827-832, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25525123

RESUMO

A Gram-reaction-negative, flexirubin-type-pigmented, rod-shaped, aerobic, non-motile bacterium, designated strain Z12(T), was isolated from a subsurface sediment sample. In a phylogenetic tree based on 16S rRNA gene sequences, strain Z12(T) formed a distinct clade with the members of the genus Dyadobacter (<96.7 % sequence similarity). The G+C content of genomic DNA was 45.4 %. The major fatty acids of strain Z12(T) were iso-C15 : 0, C16 : 1ω6c and/or C16 : 1ω7c (summed feature 3) and anteiso-C17 : 1 B and/or iso-C17 : 1 I (summed feature 4). The major respiratory quinone was MK-7 and the major polar lipid was phosphatidylethanolamine. On the basis of phenotypic, phylogenetic and genotypic features, strain Z12(T) is considered to represent a novel species, for which the name Dyadobacter sediminis sp. nov., is proposed. The type strain is Z12(T) ( = JCM 30073(T) = CGMCC 1.12895(T)).


Assuntos
Cytophagaceae/classificação , Sedimentos Geológicos/microbiologia , Filogenia , Microbiologia do Solo , Técnicas de Tipagem Bacteriana , Composição de Bases , China , Cytophagaceae/genética , Cytophagaceae/isolamento & purificação , DNA Bacteriano/genética , Ácidos Graxos/química , Dados de Sequência Molecular , Fosfatidiletanolaminas/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
10.
Antioxidants (Basel) ; 13(5)2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38790672

RESUMO

Soy isoflavones (SIF) are bioactive compounds with low bioavailability due to their poor water solubility. In this study, we utilized polymerized goat milk whey protein (PGWP) as a carrier to encapsulate SIF with encapsulation efficiency of 89%, particle size of 135.53 nm, and zeta potential of -35.16 mV. The PGWP-SIF nanoparticles were evaluated for their stability and in vitro digestion properties, and their ability to transport SIF was assessed using a Caco-2 cell monolayer model. The nanoparticles were resistant to aggregation when subjected to pH changes (pH 2.0 to 8.0), sodium chloride addition (0-200 mM), temperature fluctuations (4 °C, 25 °C, and 37 °C), and long-term storage (4 °C, 25 °C, and 37 °C for 30 days), which was mainly attributed to the repulsion generated by steric hindrance effects. During gastric digestion, only 5.93% of encapsulated SIF was released, highlighting the nanoparticles' resistance to enzymatic digestion in the stomach. However, a significant increase in SIF release to 56.61% was observed during intestinal digestion, indicating the efficient transport of SIF into the small intestine for absorption. Cytotoxicity assessments via the MTT assay showed no adverse effects on Caco-2 cell lines after encapsulation. The PGWP-stabilized SIF nanoparticles improved the apparent permeability coefficient (Papp) of Caco-2 cells for SIF by 11.8-fold. The results indicated that using PGWP to encapsulate SIF was an effective approach for delivering SIF, while enhancing its bioavailability and transcellular transport.

11.
Int J Med Inform ; 191: 105553, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39068892

RESUMO

BACKGROUND: Acute kidney injury (AKI) is associated with increased mortality in critically ill patients. Due to differences in the etiology and pathophysiological mechanism, the current AKI criteria put it an embarrassment to evaluate clinical therapy and prognosis. OBJECTIVE: We aimed to identify subphenotypes based on routinely collected clinical data to expose the unique pathophysiologic patterns. METHODS: A retrospective study was conducted based on the Medical Information Mart for Intensive Care IV (MIMIC-IV) and the eICU Collaborative Research Database (eICU-CRD), and a deep clustering approach was conducted to derive subphenotypes. We conducted further analysis to uncover the underlying clinical patterns and interpret the subphenotype derivation. RESULTS: We studied 14,189 and 19,382 patients with AKI within 48 h of ICU admission in the two datasets, respectively. Through our approach, we identified seven distinct AKI subphenotypes with mortality heterogeneity in each cohort. These subphenotypes displayed significant variations in demographics, comorbidities, levels of laboratory measurements, and survival patterns. Notably, the subphenotypes could not be effectively characterized using the Kidney Disease: Improving Global Outcomes (KDIGO) criteria alone. Therefore, we uncovered the unique underlying characteristics of each subphenotype through model-based interpretation. To assess the usability of the subphenotypes, we conducted an evaluation, which yielded a micro-Area Under the Receiver Operating Characteristic (AUROC) of 0.81 in the single-center cohort and 0.83 in the multi-center cohort within 48-hour of admission. CONCLUSION: We derived highly characteristic, interpretable, and usable AKI subphenotypes that exhibited superior prognostic values.


Assuntos
Injúria Renal Aguda , Fenótipo , Humanos , Masculino , Feminino , Estudos Retrospectivos , Pessoa de Meia-Idade , Idoso , Análise por Conglomerados , Prognóstico , Unidades de Terapia Intensiva , Estado Terminal , Aprendizado Profundo
12.
Talanta ; 272: 125765, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38346358

RESUMO

The addition of reagents into preformed droplets is a crucial yet intricate task in droplet-based applications where sequential reactions is required. Pico-injection offers high throughput and robustness in accomplishing this task, but the existing pico-injection techniques work in an indiscriminate manner, making it difficult to target particular groups of droplets. Here we report image-activated pico-injection (imgPico) for label-free, on-demand reagent supplementation into droplets. The imgPico detects the droplets of interest by real-time image analysis and makes decisions for the downstream pico-injection operation. We studied the performance of different algorithms for the image analysis and optimized the experimental settings of the imgPico. In the validation experiment, the imgPico successfully injected fluorescent dyes into droplets encapsulating one, two, and three cells, respectively, as expected. We further demonstrated the utility of imgPico by targeting droplets encapsulating single cells in droplet-based single-cell RNA sequencing (scRNA-seq) using exceedingly high cell density, and the results showed that the imgPico effectively reduced the presence of doublets in the scRNA-seq data. With the merits of being label-free and versatile, the imgPico represents a technical advance with potential applications in single-cell analysis.


Assuntos
Algoritmos , Análise de Célula Única , Análise de Célula Única/métodos , Contagem de Células
13.
Elife ; 122024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38770735

RESUMO

Osteoarthritis (OA) is a degenerative disease with a high prevalence in the elderly population, but our understanding of its mechanisms remains incomplete. Analysis of serum exosomal small RNA sequencing data from clinical patients and gene expression data from OA patient serum and cartilage obtained from the GEO database revealed a common dysregulated miRNA, miR-199b-5p. In vitro cell experiments demonstrated that miR-199b-5p inhibits chondrocyte vitality and promotes extracellular matrix degradation. Conversely, inhibition of miR-199b-5p under inflammatory conditions exhibited protective effects against damage. Local viral injection of miR-199b-5p into mice induced a decrease in pain threshold and OA-like changes. In an OA model, inhibition of miR-199b-5p alleviated the pathological progression of OA. Furthermore, bioinformatics analysis and experimental validation identified Gcnt2 and Fzd6 as potential target genes of MiR-199b-5p. Thus, these results indicated that MiR-199b-5p/Gcnt2 and Fzd6 axis might be a novel therapeutic target for the treatment of OA.


Assuntos
Receptores Frizzled , MicroRNAs , Osteoartrite , MicroRNAs/genética , MicroRNAs/metabolismo , Osteoartrite/genética , Osteoartrite/patologia , Osteoartrite/metabolismo , Animais , Receptores Frizzled/genética , Receptores Frizzled/metabolismo , Camundongos , Humanos , Masculino , Camundongos Endogâmicos C57BL , Condrócitos/metabolismo , Modelos Animais de Doenças , Regulação da Expressão Gênica
14.
Foods ; 12(19)2023 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-37835278

RESUMO

Goat milk whey protein products are a hard-to-source commodity. Whey protein concentrate was directly prepared from fresh goat milk. The effects of the heating temperature (69-78 °C), time (15-30 min), and pH (7.5-7.9) on the physicochemical and functional properties of the goat milk whey protein were investigated. The results showed that the particle size of the samples significantly increased (p < 0.05) after heat treatment. The zeta potential of polymerized goat milk whey protein (PGWP) was lower than that of native goat milk whey protein. The content of the free sulfhydryl groups of PGWP decreased with increasing heating temperature and time, while an increase in surface hydrophobicity and apparent viscosity of PGWP were observed after heat treatment. Fourier Transform Infrared Spectroscopy analysis indicated that heat treatment and pH had considerable impacts on the secondary structure of goat milk whey protein. Transmission electron microscope images revealed that heat induced the formation of a large and uniform protein network. Additionally, the changes in the physicochemical and structural properties contributed to the improvement of the emulsifying and foaming properties of goat milk whey protein after heat treatment. The results may provide a theoretical basis for the applications of polymerized goat milk whey protein in related products.

15.
Guang Pu Xue Yu Guang Pu Fen Xi ; 32(3): 703-7, 2012 Mar.
Artigo em Zh | MEDLINE | ID: mdl-22582637

RESUMO

Melamine was used in foodstuff and feed industry as a feed additive occasionally. In the present work, melamine geometry structure was optimized by density functional theory (DFT) method. Raman and infrared spectra were calculated based on MP2/6-31G sets and DFT/DGTIVP sets, and then two theoretical Raman spectra were carefully compared with other experimental spectra. Good agreements were obtained between the theoretical and experimental results. Melamine structure parameters were given also in the paper including bond lengths and bond angles. Vibrational modes were assigned to all bands in the 550-4 000 cm(-1) range. This work will benefit the measurement research of the content of melamine in foods.

16.
Front Psychol ; 13: 980453, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36312169

RESUMO

Exploring the relationship between characteristics of the source of knowledge and knowledge transfer performance seems to be crucial in order to make up for the lack of research on the political skills of knowledge sources in the process of knowledge transfer. For this reason, this study conducts a paired-sample questionnaire survey to achieve the research purpose. One direct supervisor was paired with 1∼4 subordinates; 274 other-reported questionnaires were sent out to supervisors and 1,096 self-reported questionnaires to subordinates. A total of 214 valid supervisor questionnaires and 630 valid subordinate questionnaires were collected. The finding demonstrates that knowledge sources with political skills can reduce knowledge barriers to knowledge transfer as well as affect knowledge transfer performance. This research presents a valid model that comprises the antecedents (characteristics of the knowledge source), mediators (knowledge barriers), moderators (political skill), and consequences of knowledge transfer performance of firms. Moreover, this study provides several meaningful directions for future research.

17.
JMIR Hum Factors ; 9(4): e40933, 2022 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-36548027

RESUMO

BACKGROUND: Workplace mental health is under-studied in China, making it difficult to design effective interventions. To encourage the engagement with interventions, it is crucial to understand employees' motivation toward seeking help through technologies. OBJECTIVE: This study aimed to understanding how Chinese employees view digital mental health support technology and how mental health support technology could be designed to boost the motivation of Chinese employees to use it. METHODS: A mixed methods approach was used. In total, 458 Chinese employees (248/458, 54% female) in 5 industries (manufacturing, software, medical, government, and education) responded to a survey, and 14 employees and 5 managers were interviewed. RESULTS: Government data and employee responses showed that mental health support in China is limited. In the workplace, Chinese employees experience a lower sense of autonomy satisfaction compared with competence and relatedness. Although managers and employees try to empathize with those who have mental health issues, discrimination and the stigma of mental illness are rife in Chinese workplaces. Digital technologies are perceived as a potential medium for mental health interventions; however, privacy is a major concern. CONCLUSIONS: The results of this study demonstrated the potential of self-help digital mental health support for Chinese employees. Interdisciplinary cooperation between design engineers and mental health researchers can contribute toward understanding the issues that engage or disengage users with digital mental health interventions.

18.
Vis Comput Ind Biomed Art ; 5(1): 20, 2022 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-35918564

RESUMO

Pancreatoscopy plays a significant role in the diagnosis and treatment of pancreatic diseases. However, the risk of pancreatoscopy is remarkably greater than that of other endoscopic procedures, such as gastroscopy and bronchoscopy, owing to its severe invasiveness. In comparison, virtual pancreatoscopy (VP) has shown notable advantages. However, because of the low resolution of current computed tomography (CT) technology and the small diameter of the pancreatic duct, VP has limited clinical use. In this study, an optimal path algorithm and super-resolution technique are investigated for the development of an open-source software platform for VP based on 3D Slicer. The proposed segmentation of the pancreatic duct from the abdominal CT images reached an average Dice coefficient of 0.85 with a standard deviation of 0.04. Owing to the excellent segmentation performance, a fly-through visualization of both the inside and outside of the duct was successfully reconstructed, thereby demonstrating the feasibility of VP. In addition, a quantitative analysis of the wall thickness and topology of the duct provides more insight into pancreatic diseases than a fly-through visualization. The entire VP system developed in this study is available at https://github.com/gaoyi/VirtualEndoscopy.git .

19.
Ying Yong Sheng Tai Xue Bao ; 33(5): 1215-1222, 2022 May.
Artigo em Zh | MEDLINE | ID: mdl-35730079

RESUMO

We analyzed the spatial distribution pattern and correlation of the top four dominant tree species in a 2 hm2 karst secondary forest plot of Tianlong Mountain in central Guizhou, using pairwise correlation function g(r) combined with a completely random model (CSR). The results showed that the diameter structure of trees followed an inverted J-shape, and that more trees belonged to diameter class Ⅴ (≥10 cm) driven by the dominant trees of Lithocarpus confinis and Platycarya longipes. L. confinis presented an inverted J-shaped distribution, and the population could renew very well and was in the primary growth stage. The abundance of P. longipes and Itea yunnanensis increased gradually with increasing diameter class. The density of grown and large trees was far more than the young and small individuals, which indicated poor population regeneration, and the population was in the middle and late growth stages. The top dominant tree species, except L. confinis, showed clustering distribution at large scale, which was decreased gradually with scale and trended to distribute randomly. The pattern was particularly prominent in the diameter class for young trees. Different diameter classes of different tree species presented diffe-rent spatial distribution patterns which influenced by many factors. In terms of interspecific associations, the four dominant tree species showed negative or no associations. The higher importance value of tree species, the lower the degree of association with other dominant species. The two negative correlation tree species had the lowest degree of correlation at small scale. With the increase of spatial scale, the degree of negative correlation decreased gradually, and tended to be no correlation.


Assuntos
Florestas , Árvores , China , Humanos
20.
Trop Med Infect Dis ; 7(9)2022 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-36136620

RESUMO

Background: With the progress of urbanization, the mobility of people has gradually increased, which has led to the further spread of dengue fever. This study evaluated the transmissibility of dengue fever within districts and between different districts in Zhanjiang City to provide corresponding advice for cross-regional prevention and control. Methods: A mathematical model of transmission dynamics was developed to explore the transmissibility of the disease and to compare that between different regions. Results: A total of 467 DF cases (6.38 per 100,000 people) were reported in Zhanjiang City in 2018. In the model, without any intervention, the number of simulated cases in this epidemic reached about 950. The dengue fever transmissions between districts varied within and between regions. When the spread of dengue fever from Chikan Districts to other districts was cut off, the number of cases in other districts dropped significantly or even to zero. When the density of mosquitoes in Xiashan District was controlled, the dengue fever epidemic in Xiashan District was found to be significantly alleviated. Conclusions: When there is a dengue outbreak, timely measures can effectively control it from developing into an epidemic. Different prevention and control measures in different districts could efficiently reduce the risk of disease transmission.

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