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1.
Sensors (Basel) ; 22(7)2022 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-35408188

RESUMO

Despite the great progress in 3D pose estimation from videos, there is still a lack of effective means to extract spatio-temporal features of different granularity from complex dynamic skeleton sequences. To tackle this problem, we propose a novel, skeleton-based spatio-temporal U-Net(STUNet) scheme to deal with spatio-temporal features in multiple scales for 3D human pose estimation in video. The proposed STUNet architecture consists of a cascade structure of semantic graph convolution layers and structural temporal dilated convolution layers, progressively extracting and fusing the spatio-temporal semantic features from fine-grained to coarse-grained. This U-shaped network achieves scale compression and feature squeezing by downscaling and upscaling, while abstracting multi-resolution spatio-temporal dependencies through skip connections. Experiments demonstrate that our model effectively captures comprehensive spatio-temporal features in multiple scales and achieves substantial improvements over mainstream methods on real-world datasets.


Assuntos
Compressão de Dados , Redes Neurais de Computação , Humanos , Pressão , Semântica , Esqueleto
2.
Chem Commun (Camb) ; 58(35): 5363-5366, 2022 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-35411363

RESUMO

A catalytic asymmetric construction of the bispiro[pyrazolone-dihydropyrrole-oxindole] skeleton catalyzed by chiral DMAP-derived catalyst was successfully achieved by employing recently explored pyrazolone-derived MBH carbonate in high yields with excellent stereoselectivities. The proposed transition state indicated that the intermolecular hydrogen bonds and π-π interactive forces played an essential role in stereoselective chemical transformation.


Assuntos
Pirazolonas , Carbonatos , Catálise , Reação de Cicloadição , Estrutura Molecular , Oxindóis , Pirróis , Esqueleto , Estereoisomerismo
3.
Proc Natl Acad Sci U S A ; 119(15): e2106743119, 2022 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-35389750

RESUMO

SignificanceSubsistence shifts from hunting and gathering to agriculture over the last 12,000 y have impacted human culture, biology, and health. Although past human health cannot be assessed directly, adult stature variation and skeletal indicators of nonspecific stress can serve as proxies for health during growth and development. By integrating paleogenomic genotype and osteological stature data on a per-individual basis for 167 prehistoric Europeans, we observe relatively shorter than expected statures among early farmers after correcting for individual genetic contributions to stature. Poorer nutrition and/or increased disease burdens for early agriculturalists may partly underscore this result. Our integrated osteological-genetic model has exciting potential for studies of past human health and expansion into various other contexts.


Assuntos
Agricultura , Estatura , Fazendeiros , Saúde , Esqueleto , Adulto , Agricultura/história , Estatura/genética , Criança , DNA Antigo , Europa (Continente) , Fazendeiros/história , Variação Genética , Genômica , Saúde/história , História Antiga , Humanos , Paleopatologia , Esqueleto/anatomia & histologia
4.
Proc Natl Acad Sci U S A ; 119(16): e2120177119, 2022 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-35412906

RESUMO

SignificanceBiominerals are extraordinarily intricate and possess superior mechanical properties compared with their synthetic counterparts. In this study, we show that the presence of high-Mg calcite nanoparticles within a low-Mg calcite matrix is a widespread phenomenon among marine organisms whose skeletons are composed of high-Mg calcite. It seems most likely that formation of such a complex structure is possible because of the phase separation that occurs as a result of spinodal decomposition of an amorphous Mg-calcium carbonate precursor and is followed by crystallization. We demonstrate that the basis of such phase separation stems from chemical composition rather than from biological similarities. The presence of high-Mg calcite nanoparticles increases the skeletons' toughness and hardness.


Assuntos
Biomineralização , Carbonato de Cálcio , Magnésio , Nanopartículas , Esqueleto , Animais , Carbonato de Cálcio/química , Cristalização , Magnésio/química , Nanopartículas/química , Esqueleto/química
5.
J Org Chem ; 87(9): 6426-6431, 2022 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-35439001

RESUMO

An intramolecular formal [3+2] cycloaddition of activated aziridines and epoxides with electron-deficient alkene has been developed for the general and efficient construction of bridged aza- and oxa-[n.2.1] (n = 3 or 4) skeletons. This strategy can be efficiently promoted by lithium iodide. To demonstrate its potential, the intramolecular formal [3+2] cycloaddition was used to access the important intermediate of homoepiboxidine.


Assuntos
Alcenos , Aziridinas , Catálise , Reação de Cicloadição , Elétrons , Compostos de Epóxi , Esqueleto
6.
Org Lett ; 24(14): 2684-2688, 2022 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-35389665

RESUMO

Chevalinulins A (1) and B (2), two indole diketopiperazine alkaloids containing an unprecedented spiro[bicyclo[2.2.2]octane-diketopiperazine] skeleton, together with a known analogue neoechinulin B (3), were isolated from the deep-sea cold-seep-derived fungus Aspergillus chevalieri CS-122. Their structures were determined by spectroscopic analysis, single-crystal X-ray diffraction, specific rotation (SR), and NMR calculations. Compounds 1 and 2 exhibited significant in vivo proangiogenic activity in transgenic zebrafish.


Assuntos
Alcaloides , Dicetopiperazinas , Alcaloides/química , Animais , Aspergillus , Dicetopiperazinas/química , Fungos , Alcaloides Indólicos/química , Estrutura Molecular , Octanos , Esqueleto , Peixe-Zebra
8.
An Acad Bras Cienc ; 94(suppl 1): e20191467, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35384969

RESUMO

Ice-free areas of Antarctica represent an important study region that helps us understand how human activity affects plant communities and soil properties. The goal of this study was to determine the changes in plant composition and soil properties around a whale bone skeleton (WB) near Ferraz Station, King George Island, Antarctica from 1972 to 2020 (48 years). The WB was assembled in 1972 by Jacques-Yves Cousteau and his team. It is located in a large moss field and visited by many tourists. We studied the plant composition and development based on historical and recent photographs and phytosociological studies from 1986 to 2020. The soil was sampled in February 2009 to determine general properties. The results showed that human activity surrounding the WB directly affected the plant community composition and soil properties. The Syntrichia cushions were positively affected by the calcium deposits from bone dissolution. The principal component analysis revealed that mineralization of the bones increased soil nutrient assembly. A strong phosphatization process was observed in the WB area, similar to that in ornithogenic soils. The WB on the marine terrace enhanced soil fertility and changed the plant community.


Assuntos
Poluentes do Solo , Solo , Animais , Regiões Antárticas , Esqueleto , Microbiologia do Solo , Poluentes do Solo/análise , Baleias
9.
Tech Vasc Interv Radiol ; 25(1): 100804, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35248322

RESUMO

This article aims to disclose a consensus on the rationale, approaches, and the outcomes of bone ablations in the peripheral skeleton. Despite less numerous prospective studies about peripheral metastasis, interventional radiology has a role in this setting. Scrupulous attention for selection criteria, ablation technique, procedural steps, and clinical and imaging follow-up are required to provide optimal multidisciplinary care for oncologic patients.


Assuntos
Técnicas de Ablação , Ablação por Cateter , Técnicas de Ablação/efeitos adversos , Humanos , Seleção de Pacientes , Estudos Prospectivos , Radiologia Intervencionista , Esqueleto
10.
Fitoterapia ; 158: 105173, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35288210

RESUMO

A pair of enantiomers with a rearranged dimeric phenylethanol skeleton, namely (±)-disyringol A (1a and 1b), were isolated from the stem barks of Syringa pinnatifolia. The structures were established using IR, UV, MS, and NMR data, and their absolute configurations were resolved by experimental and calculated ECD data analysis. Their biosynthetic pathway was speculated on the basis of a phenylethanoid precursor and was proved by a total synthesis. Compounds 1a and 1b showed the inhibition against NO production in LPS-induced RAW264.7 cells with their IC50 values of 27.28 and 24.64 µM, respectively, however no protective effect was observed against the hypoxia-induced injuries to H9c2 cells.


Assuntos
Syringa , Animais , Camundongos , Estrutura Molecular , Células RAW 264.7 , Esqueleto , Estereoisomerismo , Syringa/química
11.
Acc Chem Res ; 55(6): 916-929, 2022 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-35239333

RESUMO

Macrocyclic compounds are fundamental tools in supramolecular chemistry and have been widely used in molecular recognition, biomedicine, and materials science. The construction of new macrocycles with distinctive structures and properties would unleash new opportunities for supramolecular chemistry. Traditionally popular macrocycles, e.g., cyclodextrins, calixarenes, cucurbiturils, and pillararenes, possess specific cavities that are usually less than 10 Å in diameter; they are normally suitable for accommodating small- or medium-sized guests but cannot engulf giant molecules or structures. Furthermore, the skeletons of traditional macrocycles are impoverished and incapable of being changed; functional substituents can be introduced only on their portals.Thus, it is very challenging to construct macrocycles with customizable cavity sizes and/or diverse backbones. We have developed a versatile and modular strategy for synthesizing macrocycles, namely, biphen[n]arenes (n = 3-8), based on the structure- or function-oriented replacement of reaction modules, functional modules, and linking modules. First, two reaction modules and one functional module are connected by Suzuki-Miyaura coupling to obtain a monomer having two reaction sites. Then Friedel-Crafts alkylation between the monomer and an aldehyde (linking module) serves to afford diversely functionalized macrocycles. Moreover, large macrocycles can be achieved by using long and rigid oligo(para-phenylene) monomers. Because of the modular synthesis and plentiful molecular supplies, the biphen[n]arenes showed interesting recognition properties for both small molecules and large polypeptides. Customizable functional backbones and binding sites endowed this new family of macrocycles with peculiar self-assembly properties and potential applications in gas chromatography, pollutant capture, and physisorptive separation. Biphen[n]arenes would be a promising family of workhorses in supramolecular chemistry.In this Account, we summarize our recent work on the chemistry of biphen[n]arenes. We introduce their design and modular synthesis, including systematic exploration for reaction modules, customizable cavity sizes, skeleton functionalization, pre- and postmodification, and molecular cages. Thereafter, we discuss their host-guest properties, involving the binding for small guests by cationic/anionic/neutral biphen[n]arenes, as well as the complexation of polypeptides by large quaterphen[n]arenes. In addition, we outline the self-assembly and potential applications of this new family of macrocycles. Finally, we forecast their further development. The chemistry of biphen[n]arenes is still in its infancy. Continued exploration will not only further expand the supramolecular toolbox but also open new avenues for the use of biphen[n]arenes in the fields of biology, pharmaceutical science, and materials science.


Assuntos
Calixarenos , Ciclodextrinas , Calixarenos/química , Cátions , Ciclodextrinas/química , Peptídeos , Esqueleto
12.
Sensors (Basel) ; 22(6)2022 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-35336262

RESUMO

Human action recognition has been applied in many fields, such as video surveillance and human computer interaction, where it helps to improve performance. Numerous reviews of the literature have been done, but rarely have these reviews concentrated on skeleton-graph-based approaches. Connecting the skeleton joints as in the physical appearance can naturally generate a graph. This paper provides an up-to-date review for readers on skeleton graph-neural-network-based human action recognition. After analyzing previous related studies, a new taxonomy for skeleton-GNN-based methods is proposed according to their designs, and their merits and demerits are analyzed. In addition, the datasets and codes are discussed. Finally, future research directions are suggested.


Assuntos
Algoritmos , Reconhecimento Automatizado de Padrão , Atividades Humanas , Humanos , Redes Neurais de Computação , Reconhecimento Automatizado de Padrão/métodos , Esqueleto
13.
Chin J Nat Med ; 20(2): 148-154, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35279242

RESUMO

Four new sesquiterpene quinone meroterpenoids, dysideanones F-G (1-2) and dysiherbols D-E (3-4), were isolated from the marine sponge Dysidea avara collected from the South China Sea. The new structures were elucidated by extensive analysis of spectroscopic data including HR-MS and 1D and 2D NMR spectra, and their absolute configurations were assigned by single-crystal X-ray diffraction and ECD calculations. Anti-inflammatory evaluation showed that dysiherbols D-E (3-4) exhibited moderate inhibitory activity on TNF-α-induced NF-κB activation in human HEK-293T cells with IC50 values of 10.2 and 8.6 µmol·L-1, respectively.


Assuntos
Dysidea , Poríferos , Sesquiterpenos , Animais , Dysidea/química , Quinonas/química , Quinonas/farmacologia , Sesquiterpenos/química , Sesquiterpenos/farmacologia , Esqueleto
14.
Front Immunol ; 13: 850338, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35281045

RESUMO

Stony corals are among the most important calcifiers in the marine ecosystem as they form the coral reefs. Coral reefs have huge ecological importance as they constitute the most diverse marine ecosystem, providing a home to roughly a quarter of all marine species. In recent years, many studies have shed light on the mechanisms underlying the biomineralization processes in corals, as characterizing the calicoblast cell layer and genes involved in the formation of the calcium carbonate skeleton. In addition, considerable advancements have been made in the research field of coral immunity as characterizing genes involved in the immune response to pathogens and stressors, and the revealing of specialized immune cells, including their gene expression profile and phagocytosis capabilities. Yet, these two fields of corals research have never been integrated. Here, we discuss how the coral skeleton plays a role as the first line of defense. We integrate the knowledge from both fields and highlight genes and proteins that are related to biomineralization and might be involved in the innate immune response and help the coral deal with pathogens that penetrate its skeleton. In many organisms, the immune system has been tied to calcification. In humans, immune factors enhance ectopic calcification which causes severe diseases. Further investigation of coral immune genes which are involved in skeleton defense as well as in biomineralization might shed light on our understanding of the correlation and the interaction of both processes as well as reveal novel comprehension of how immune factors enhance calcification.


Assuntos
Antozoários , Calcinose , Animais , Antozoários/genética , Antozoários/metabolismo , Biomineralização , Ecossistema , Sistema Imunitário , Esqueleto
15.
Sci Rep ; 12(1): 4111, 2022 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-35260760

RESUMO

There has been significant progress in skeleton-based action recognition. Human skeleton can be naturally structured into graph, so graph convolution networks have become the most popular method in this task. Most of these state-of-the-art methods optimized the structure of human skeleton graph to obtain better performance. Based on these advanced algorithms, a simple but strong network is proposed with three major contributions. Firstly, inspired by some adaptive graph convolution networks and non-local blocks, some kinds of self-attention modules are designed to exploit spatial and temporal dependencies and dynamically optimize the graph structure. Secondly, a light but efficient architecture of network is designed for skeleton-based action recognition. Moreover, a trick is proposed to enrich the skeleton data with bones connection information and make obvious improvement to the performance. The method achieves 90.5% accuracy on cross-subjects setting (NTU60), with 0.89M parameters and 0.32 GMACs of computation cost. This work is expected to inspire new ideas for the field.


Assuntos
Redes Neurais de Computação , Esqueleto , Algoritmos , Humanos , Reconhecimento Psicológico
16.
Bioorg Med Chem Lett ; 64: 128654, 2022 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-35259487

RESUMO

In this study, a novel batch of indazole containing 1,2,3-triazole agents were designed and synthesized. The antiproliferative activity of target compounds in four human cancer cells, PC-3 (human prostate cancer cell), MCF-7 (human breast cancer cell), HepG-2 (human hepatoma cell) and MGC-803 (human gastric cancer cell), was evaluated by thiazole blue (MTT). In the antiproliferative activity screening, we were surprised to find that most compounds have specific cytotoxicity to PC-3 cancer cells. In particular, 9a has an IC50 value of 4.42 ± 0.06 µmol/L against PC-3 cell. Cloning experiments showed that 9a could inhibit the formation of PC-3 cancer cell clone in a dose-dependent manner. Through cell cycle arrest experiment, we found that compound 9a can block the cell cycle in G2/M phase and inhibit cell proliferation. Finally, by evaluating the safety of compound 9a, we noticed that it showed fairly good safety both in vivo and in vitro. Overall, based on the biological activity evaluation and safety, analogue 9a can be viewed as a potential lead compound for further development of novel anti-prostate cancer drug.


Assuntos
Antineoplásicos , Neoplasias da Próstata , Antineoplásicos/farmacologia , Apoptose , Linhagem Celular Tumoral , Proliferação de Células , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Indazóis/farmacologia , Masculino , Estrutura Molecular , Neoplasias da Próstata/tratamento farmacológico , Esqueleto , Relação Estrutura-Atividade , Triazóis/farmacologia
17.
Sci Total Environ ; 827: 154252, 2022 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-35247403

RESUMO

On the basis of the carbonaceous skeleton assisted thermal hydrolysis that we proposed to achieve efficient sludge dewatering, this work further explored phosphorus (P) transformation in the process. The results showed that during independent thermal hydrolysis in the temperature range of 120-240 °C, organic-P was first decomposed into soluble-P and particulate-P in liquid, and then combined with Ca, Fe, and Al to form more apatite-P (AP) and less non-apatite inorganic-P (NAIP). When the skeleton assisted the sludge thermal hydrolysis, the turning point of the hydrolysis temperature would reduce from 180 °C to 150 °C, at which the liquid-P began to decrease and the organic-P generally decomposed. Moreover, the increment in the content of AP halved while that of NAIP doubled compared to that in the process without the carbonaceous skeleton. These effects come from the exogenous components introduced by adding the skeleton, which were different from the sludge. Compared with the P-rich compound and metal elements that tend to bond with phosphate introduced by the skeleton, hemicellulose as a main organic component played a leading role in the different P transformations of AP and NAIP. The hemicellulose slightly increased the acidity of sludge products, thereby inhibiting AP production and promoting the production of recyclable NAIP. Overall, the carbonaceous skeleton assisted thermal hydrolysis was beneficial for P recovery with a very low filtrate loss rate.


Assuntos
Fósforo , Esgotos , Apatitas/química , Hidrólise , Fosfatos/química , Fósforo/química , Esgotos/química , Esqueleto
18.
Int J Mol Sci ; 23(6)2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-35328584

RESUMO

Byproducts obtained from fish processing account for up to 70% of their live weight and represent a large amount of unused raw materials rich in proteins, fats, minerals, and vitamins. Recently, the management of the use of predominantly cold-water fish byproducts has become a priority for many processing companies. This paper describes the biotechnological processing of byproducts of warm-water Cyprinus carpio skeletons into gelatins. A Taguchi experimental design with two process factors (HCl concentration during demineralization of the starting material and the amount of enzyme during enzyme conditioning of the collagen) examined at three levels (0.5, 1.0 and 2.0 wt%; 0.0, 0.1 and 0.2 wt% respectively) was used to optimize the processing of fish tissue into gelatin. Depending on the preparation conditions, four gelatin fractions were prepared by multi-stage extraction from the starting material with a total yield of 18.7-55.7%. Extensive characterization of the gel-forming and surface properties of the prepared gelatins was performed. Gelatins belong to the group of zero-low-medium Bloom value (0-170 Bloom) and low-medium viscosity (1.1-4.9 mPa·s) gelatins and are suitable for some food, pharmaceutical, and cosmetic applications. During processing, the pigment can be isolated; the remaining solid product can then be used in agriculture, and H3PO4Ca can be precipitated from the liquid byproduct after demineralization. The carp byproduct processing technology is environmentally friendly and meets the requirements of zero-waste technology.


Assuntos
Carpas , Gelatina , Animais , Colágeno , Esqueleto , Água
19.
Eur J Radiol ; 149: 110223, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35240412

RESUMO

OBJECTIVES: Objective evaluation of the extent of skeletal marrow involvement in multiple myeloma remains a clinical gap for CT. We aimed to develop a quantitative segmentation pipeline for dual energy CT and to assess whether quantified whole skeleton calcium-subtracted attenuation values correlate with biopsy-derived bone marrow infiltration in multiple myeloma. METHODS: Consecutive prospective patients with suspected/established myeloma underwent dual source CT from the skull vertex to proximal tibia. Whole skeleton segmentation was performed for 120 kVp-equivalent images as follows: following Hounsfield unit (HU) thresholding, a Chan-Vese morphological operation was implemented to generate a whole skeleton segmentation mask. This mask was then applied to corresponding whole skeleton material decomposition calcium-subtracted maps, generating whole skeleton HU values. Associations with biopsy-derived bone marrow plasma cell infiltration percentage were assessed with Spearman's rank correlation; significance was at 5%. RESULTS: 21 patients (12 females; median (IQR) 67 (61, 73) years) were included; 16 patients had osteolytic bone lesions; 15 patients underwent bone marrow biopsy. Segmentation and quantification were feasible in all patients. Median (IQR) of the average skeletal calcium-subtracted attenuation was -59.9 HU (-66.3, -51.8HU). There was a positive correlation with bone marrow plasma cell infiltration percentage (Spearman's rho: + 0.79, p < 0.001). CONCLUSION: Whole skeleton calcium-subtracted attenuation is associated with the degree of bone marrow infiltration by plasma cells, providing an objective measure of marrow involvement with the potential to allow earlier detection of disease.


Assuntos
Medula Óssea , Mieloma Múltiplo , Medula Óssea/diagnóstico por imagem , Medula Óssea/patologia , Cálcio , Feminino , Humanos , Mieloma Múltiplo/diagnóstico por imagem , Mieloma Múltiplo/patologia , Estudos Prospectivos , Esqueleto/patologia , Tomografia Computadorizada por Raios X/métodos
20.
Sensors (Basel) ; 22(3)2022 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-35161605

RESUMO

In this paper, a new algorithm for extracting the laser fringe center is proposed. Based on a deep learning skeleton extraction network, the laser stripe center can be extracted quickly and accurately. Skeleton extraction is the process of reducing the shape image to its approximate central axis representation while maintaining the image's topological and geometric shape. Skeleton extraction is an important step in topological and geometric shape analysis. According to the characteristics of the wheelset laser curve dataset, a new skeleton extraction network, a hierarchical skeleton network (LuoNet), is proposed. The proposed architecture has three levels of the encoder-decoder network, and YE Module interconnection is designed between each level of the encoder and decoder network. In the wheelset laser curve dataset, the F1_score can reach 0.714. Compared with the traditional laser curve center extraction algorithm, the proposed LuoNet algorithm has the advantages of short running time, high accuracy, and stable extraction results.


Assuntos
Aprendizado Profundo , Algoritmos , Processamento de Imagem Assistida por Computador , Lasers , Esqueleto
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