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1.
Microsc Res Tech ; 86(11): 1529-1541, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37382312

RESUMO

During orthodontic tooth movement (OTM), osteocytes, the most mechanosensitive cells in alveolar bone, suffer the heavy orthodontic force and initiate alveolar bone resorption on the compression side. However, the inherent mechanisms of compressive force-induced osteocyte death are not fully understood. In this study, we established an OTM model on Sprague-Dawley rats by inserting coil springs to investigate osteocyte damage on the compression side of alveolar bone. We then applied compressive force on the MLO-Y4 osteocyte-like cell line in vitro to explore whether the reactive oxygen species (ROS)-mediated endoplasmic reticulum stress (ERS) pathway is involved in compressive force-induced osteocyte death. We found that the orthodontic force caused apparent alveolar bone loss, osteocyte death, and elevated serum sclerostin and receptor activator of NF-κB ligand (RANKL) levels in rats. In vitro, compressive force inhibited cell viability but increased the LDH leakage and loss of mitochondrial membrane potential in MLO-Y4 cells. Simultaneously, it activated protein kinase RNA-like endoplasmic reticulum kinase (PERK), eukaryotic translation initiation factor 2 (eIF2α), and their downstream pro-apoptotic ERS signaling proteins and caused significant osteocyte apoptosis, which can be blocked by ERS inhibitor salubrinal. Moreover, the compressive force elevated intracellular ROS levels, while the ROS scavenger N-acetyl-L-cysteine (NAC) alleviated ERS and apoptosis in loaded osteocytes. These results suggest that the orthodontic compressive force induced osteocyte apoptosis via the ROS-mediated ERS pathway. This study first proposes the ERS pathway as a new potential pathway for regulating the rate of OTM based on osteocyte death. RESEARCH HIGHLIGHTS: The orthodontic force increases osteocyte death in rat alveolar bone. The compressive force causes osteocyte apoptosis by the endoplasmic reticulum stress (ERS) pathway in vitro. The ROS scavenger NAC blocked compressive force-induced ERS and osteocyte apoptosis.


Assuntos
Perda do Osso Alveolar , Osteócitos , Ratos , Animais , Espécies Reativas de Oxigênio/metabolismo , Ratos Sprague-Dawley , Transdução de Sinais , Perda do Osso Alveolar/metabolismo , Estresse do Retículo Endoplasmático , Apoptose
2.
Sheng Wu Gong Cheng Xue Bao ; 38(3): 976-989, 2022 Mar 25.
Artigo em Chinês | MEDLINE | ID: mdl-35355468

RESUMO

Human body can obtain energy from either carbohydrate or fat digestion. Although glucose metabolism derived from carbohydrate-based diets has long been utilized for energy supply, it has been recently discovered that shifting from glucose to fatty acid metabolism may become a novel way for improving human health especially when carbohydrate is deprived. In recent years, intermittent fasting and ketogenic diets have received a lot of attention in respect to favoring fatty acid metabolism. In all cases, fatty acid metabolism produces D-ß-hydroxybutyrate (D3HB), which is a natural ketone body, as well as, a monomer of microbial poly-D-ß-hydroxybutyrate (PHB). D3HB can be utilized by different cells of the body as an alternative energy fuel or an intracellular signaling molecule with multiple downstream signaling pathways. Usually, the serum level of D3HB is increased during ketogenic diets, however, requires a very long period of adaptation (over 3-months) and exhibits unwanted adverse effects. Hence, exogenous ketone supplements using D3HB have become a more effective approach to induce and maintain nutritional ketosis for subsequent functional effects. This review describes how D3HB is produced and metabolized within the body, the functional roles played by D3HB, and a detailed summary of the different applications of exogenous ketones that have been explored to date in both nutritional and therapeutical context.


Assuntos
Corpos Cetônicos , Cetonas , Ácido 3-Hidroxibutírico , Suplementos Nutricionais , Glucose/metabolismo , Humanos , Corpos Cetônicos/metabolismo
3.
PeerJ Comput Sci ; 7: e802, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34909466

RESUMO

Massive plant hyperspectral images (HSIs) result in huge storage space and put a heavy burden for the traditional data acquisition and compression technology. For plant leaf HSIs, useful plant information is located in multiple arbitrary-shape regions of interest (MAROIs), while the background usually does not contain useful information, which wastes a lot of storage resources. In this paper, a novel hyperspectral compressive sensing framework for plant leaves with MAROIs (HCSMAROI) is proposed to alleviate these problems. HCSMAROI only compresses and reconstructs MAROIs by discarding the background to achieve good reconstructed performance. But for different plant leaf HSIs, HCSMAROI has the potential to be applied in other HSIs. Firstly, spatial spectral decorrelation criterion (SSDC) is used to obtain the optimal band of plant leaf HSIs; Secondly, different leaf regions and background are distinguished by the mask image of the optimal band; Finally, in order to improve the compression efficiency, after discarding the background region the compressed sensing technology based on blocking and expansion is used to compress and reconstruct the MAROIs of plant leaves one by one. Experimental results of soybean leaves and tea leaves show that HCSMAROI can achieve 3.08 and 5.05 dB higher PSNR than those of blocking compressive sensing (BCS) at the sampling rate of 5%, respectively. The reconstructed spectra of HCSMAROI are especially closer to the original ones than that of BCS. Therefore, HCSMAROI can achieve significantly higher reconstructed performance than that of BCS. Moreover, HCSMAROI can provide a flexible way to compress and reconstruct different MAROIs with different sampling rates, while achieving good reconstruction performance in the spatial and spectral domains.

4.
Appl Microbiol Biotechnol ; 105(16-17): 6229-6243, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34415393

RESUMO

D-ß-hydroxybutyrate (D-3HB), a monomer of microbial polyhydroxybutyrate (PHB), is also a natural ketone body produced during carbohydrate deprivation to provide energy to the body cells, heart, and brain. In recent years, increasing evidence demonstrates that D-3HB can induce pleiotropic effects on the human body which are highly beneficial for improving physical and metabolic health. Conventional ketogenic diet (KD) or exogenous ketone salts (KS) and esters (KE) have been used to increase serum D-3HB level. However, strict adaptation to the KD was often associated with poor patient compliance, while the ingestion of KS caused gastrointestinal distresses due to excessive consumption of minerals. As for ingestion of KE, subsequent degradation is required before releasing D-3HB for absorption, making these methods somewhat inferior. This review provides novel insights into a biologically synthesized D-3HB (D-3-hydroxybutyric acid) which can induce a faster increase in plasma D-3HB compared to the use of KD, KS, or KE. It also emphasizes on the most recent applications of D-3HB in different fields, including its use in improving exercise performance and in treating metabolic or age-related diseases. Ketones may become a fourth micro-nutrient that is necessary to the human body along with carbohydrates, proteins, and fats. Indeed, D-3HB being a small molecule with multiple signaling pathways within the body exhibits paramount importance in mitigating metabolic and age-related diseases. Nevertheless, specific dose-response relationships and safety margins of using D-3HB remain to be elucidated with more research. KEY POINTS: • D-3HB induces pleiotropic effects on physical and metabolic health. • Exogenous ketone supplements are more effective than ketogenic diet. • d-3HB as a ketone supplement has long-term healthy impact.


Assuntos
Dieta Cetogênica , Corpos Cetônicos , Ácido 3-Hidroxibutírico , Suplementos Nutricionais , Humanos , Cetonas , Proibitinas
5.
PeerJ ; 9: e11642, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34395064

RESUMO

A new hyperspectral images (HSIs) denoising method via Interpolated Block-Matching and 3D filtering and Guided Filtering (IBM3DGF) denoising method is proposed. First, inter-spectral correlation analysis is used to obtain inter-spectral correlation coefficients and divide the HSIs into several adjacent groups. Second, high-resolution HSIs are produced by using adjacent three images to interpolate. Third, Block-Matching and 3D filtering (BM3D) is conducted to reduce the noise level of each group; Fourth, the guided image filtering is utilized to denoise HSI of each group. Finally, the inverse interpolation is applied to retrieve HSI. Experimental results of synthetic and real HSIs showed that, comparing with other state-of-the-art denoising methods, the proposed IBM3DGF method shows superior performance according to spatial and spectral domain noise assessment. Therefore, the proposed method has a potential to effectively remove the spatial/spectral noise for HSIs.

6.
ISA Trans ; 92: 315-324, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30827710

RESUMO

This paper proposed a new MNF-BM4D denoising algorithm based on guided filtering to improve the denoising performance of the state-of-the-art Block-Matching and 4D filtering(BM4D) algorithm for hyperspectral images in the spatial and spectral domain. BM4D is firstly used to denoise hyperspectral images. Then Minimum Noise Fraction(MNF) algorithm is introduced to distinguish between the main component and the noisy component. Finally, the guided image filtering technology is utilized to further improve the denoising performance. A number of experiments on both simulated and real data are conducted to validate the effective denoising performance of the proposed method. Therefore, the proposed algorithm can be considered as a promising technique for hyperspectral imagery denoising.

7.
J Cell Mol Med ; 23(3): 2219-2229, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30648805

RESUMO

Tumour lymphangiogenesis plays an important role in promoting the growth and lymphatic metastasis of tumours. The process is associated with cell proliferation, migration and tube-like structure formation in lymphatic endothelial cells (LEC), but no antilymphangiogenic agent is currently used in clinical practice. Fucoxanthin is a material found in brown algae that holds promise in the context of drug development. Fucoxanthin is a carotenoid with variety of pharmacological functions, including antitumour and anti-inflammatory effects. The ability of fucoxanthin to inhibit lymphangiogenesis remains unclear. The results of experiments performed as part of this study show that fucoxanthin, extracted from Undaria pinnatifida (Wakame), inhibits proliferation, migration and formation of tube-like structures in human LEC (HLEC). In this study, fucoxanthin also suppressed the malignant phenotype in human breast cancer MDA-MB-231 cells and decreased tumour-induced lymphangiogenesis when used in combination with a conditional medium culture system. Fucoxanthin significantly decreased levels of vascular endothelial growth factor (VEGF)-C, VEGF receptor-3, nuclear factor kappa B, phospho-Akt and phospho-PI3K in HLEC. Fucoxanthin also decreased micro-lymphatic vascular density (micro-LVD) in a MDA-MB-231 nude mouse model of breast cancer. These findings suggest that fucoxanthin inhibits tumour-induced lymphangiogenesis in vitro and in vivo, highlighting its potential use as an antilymphangiogenic agent for antitumour metastatic comprehensive therapy in patients with breast cancer.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Proliferação de Células/efeitos dos fármacos , Linfangiogênese/efeitos dos fármacos , Xantofilas/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto , Animais , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Feminino , Humanos , Vasos Linfáticos/efeitos dos fármacos , Vasos Linfáticos/metabolismo , Vasos Linfáticos/patologia , Camundongos Endogâmicos BALB C , Camundongos Nus , Phaeophyceae/química , Fator C de Crescimento do Endotélio Vascular/genética , Fator C de Crescimento do Endotélio Vascular/metabolismo , Receptor 3 de Fatores de Crescimento do Endotélio Vascular/genética , Receptor 3 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Xantofilas/química
8.
Sensors (Basel) ; 18(10)2018 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-30274352

RESUMO

In order to improve the performance of storage and transmission of massive hyperspectral data, a prediction-based spatial-spectral adaptive hyperspectral compressive sensing (PSSAHCS) algorithm is proposed. Firstly, the spatial block size of hyperspectral images is adaptively obtained according to the spatial self-correlation coefficient. Secondly, a k-means clustering algorithm is used to group the hyperspectral images. Thirdly, we use a local means and local standard deviations (LMLSD) algorithm to find the optimal image in the group as the key band, and the non-key bands in the group can be smoothed by linear prediction. Fourthly, the random Gaussian measurement matrix is used as the sampling matrix, and the discrete cosine transform (DCT) matrix serves as the sparse basis. Finally, the stagewise orthogonal matching pursuit (StOMP) is used to reconstruct the hyperspectral images. The experimental results show that the proposed PSSAHCS algorithm can achieve better evaluation results-the subjective evaluation, the peak signal-to-noise ratio, and the spatial autocorrelation coefficient in the spatial domain, and spectral curve comparison and correlation between spectra-reconstructed performance in the spectral domain-than those of single spectral compression sensing (SSCS), block hyperspectral compressive sensing (BHCS), and adaptive grouping distributed compressive sensing (AGDCS). PSSAHCS can not only compress and reconstruct hyperspectral images effectively, but also has strong denoise performance.

9.
Zhongguo Ying Yong Sheng Li Xue Za Zhi ; 34(4): 299-303 317, 2018 Apr 08.
Artigo em Chinês | MEDLINE | ID: mdl-30788935

RESUMO

OBJECTIVE: To explore the effect of ambient particle matter 2.5 (PM2.5) collected in the urban center of Hangzhou on the lung injury of rats and on the activating of endoplasmic reticulum pathway. METHODS: PM2.5 samples were collected on quartz fiber filters using a PM2.5 high-volume air sampler in the urban area of Hangzhou. The collected PM2.5 particles were extracted in ultrapure water and concentrated by vacuum freeze-drying. Twenty-four male Sprague-Dawly (SD) rats were randomly divided into 3 groups:saline control group, low dose PM2.5 exposure group (5 mg/kg BW) and high dose PM2.5 exposure groups (25 mg/kg BW). Each group received intratracheal instillation of PM2.5, once a week for 4 weeks. Twenty-four hours after the last exposure, the rats were narcotized and sacrificed, left lung was isolated and fixed with 4% paraformaldehyde for histopathological detection. The bronchoalveolar lavage fluid (BALF) was collected from the right lung. The total antioxidant capacity (T-AOC) level, the activities of superoxide dismutase (SOD) and lactic dehydrogenase (LDH) in BALF were detected by chemical colorimetry. The level of tumor necrosis factor-alpha (TNF-α), interleukin-1 beta (IL-1ß) and interleukin-6 (IL-6) cytokines in BALF was measured by enzyme linked immunosorbent assay (ELISA). And the protein expressions of glucose-regulated protein 78 (GRP78), phosphorylated protein kinase receptor-like endoplasmic reticulum kinase (p-PERK), phosphorylated eukaryotic translation initiation factor (p-eIF2α), transcription factors C/EBP homologue protein (CHOP), inositol-requiring enzyme 1α (IRE1α) and X-box binding protein 1 (XBP1) in lung tissue were determined by Western blotting. RESULTS: Compared with control group, rats in both low dose (5 mg/kg) and high dose (25 mg/kg) PM2.5-treated groups showed obviously dose-dependent pulmonary toxicity including thickening of alveolar walls, narrowing of alveolar space, interstitial hyperplasia and inflammatory cell infiltration. Compared with control group, T-AOC level and the SOD activity in BALF in both PM2.5-treated groups were decreased dose-dependently (P<0.05), whereas the LDH activity in BALF were increased in a dose-dependent manner (P<0.05). Exposure to PM2.5 resulted in a increasing of the release of proinflammatory cytokines including TNF-α, IL-1ß and IL-6 in rat lung in a dose-dependent manner (P<0.05). The levels of GRP78, p-PERK, p-eIF2α, CHOP, IRE1α and spliced XBP1 (XBP1-S) were significantly up-regulated, whereas the level of unspliced XBP1 (XBP1-U) was down-regulated in the rat lung tissue of high-dose PM2.5 treated group. CONCLUSIONS: The PM2.5 in the urban area of Hangzhou can significantly cause lung inflammatory injury in rats. Both oxidative stress and activation of ER stress pathways may be related to such PM2.5 inhalation-induced lung inflammatory injury.


Assuntos
Lesão Pulmonar , Material Particulado , Animais , Líquido da Lavagem Broncoalveolar , Interleucina-6 , Pulmão , Masculino , Ratos
10.
Sensors (Basel) ; 17(6)2017 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-28590433

RESUMO

With the development of hyperspectral technology, to establish an effective spectral data compressive reconstruction method that can improve data storage, transmission, and maintaining spectral information is critical for quantitative remote sensing research and application in vegetation. The spectral adaptive grouping distributed compressive sensing (AGDCS) algorithm is proposed, which enables a distributed compressed sensing reconstruction of plant hyperspectral data. The spectral characteristics of hyperspectral data are analyzed and the joint sparse model is constructed. The spectral bands are adaptively grouped and the hyperspectral data are compressed and reconstructed on the basis of grouping. The experimental results showed that, compared with orthogonal matching pursuit (OMP) and gradient projection for sparse reconstruction (GPSR), AGDCS can significantly improve the visual effect of image reconstruction in the spatial domain. The peak signal-to-noise ratio (PSNR) at a low sampling rate (the sampling rate is lower than 0.2) increases by 13.72 dB than OMP and 1.66 dB than GPSR. In the spectral domain, the average normalized root mean square error, the mean absolute percentage error, and the mean absolute error of AGDCS is 35.38%, 31.83%, and 33.33% lower than GPSR, respectively. Additionally, AGDCS can achieve relatively high reconstructed efficiency.


Assuntos
Compressão de Dados , Algoritmos , Fenômenos Físicos , Plantas , Razão Sinal-Ruído
11.
Biotechnol Bioeng ; 105(1): 59-68, 2010 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-19725041

RESUMO

Sessile filter-feeding marine sponges (Porifera) have been reported to possess high efficiency in removing bacteria pollution from natural or aquaculture seawater. However, no investigation has been carried out thus far in a true mariculture farm water system. Therefore this study sought to investigate the ability of the marine sponge Hymeniacidon perlevis to bioremediate the bacteria pollution in the intensive aquaculture water system of turbot Scophthalmus maximus. Sponge specimens were hung in fish culture effluent at different temperature to investigate the optimal temperature condition for bacteria removal by H. perlevis. Turbots S. maximus were co-cultured with sponge H. perlevis in 1.5 m(3) of water system at 15-18 degrees C for 6 weeks to control the growth of bacteria. It was found that H. perlevis was able to remove pathogenic bacteria efficiently at 10-20 degrees C, with a maximal removal of 71.4-78.8% of fecal coliform, 73.9-98.7% of pathogenic vibrio, and 75.0-83.7% of total culturable bacteria from fish-culture effluent at 15 degrees C; H. perlevis continuously showed good bioremediation of bacteria pollution in the S. maximus culture water system, achieving removal of 60.0-90.2% of fecal coliform, 37.6-81.6% of pathogenic vibrio, and 45.1-83.9% of total culturable bacteria. The results demonstrate that H. perlevis is an effective bioremediator of bacteria pollution in the turbot S. maximus culture farm water system.


Assuntos
Biodegradação Ambiental , Linguados/microbiologia , Poríferos/microbiologia , Poluição da Água , Animais , Pesqueiros , Água do Mar , Temperatura
12.
Mar Biotechnol (NY) ; 11(5): 640-9, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19221840

RESUMO

To resolve "the supply problem" in sponge-derived drug development and other biotechnological applications, current research is exploring the possibility of obtaining an alternative sustainable supply of sponge biomass through intensive aquaculture of sponges utilizing artificial seed rearing. This study aimed to investigate the technology of early juvenile sponge cultivation under controlled conditions. The effects of food, temperature, water flow, and light on the growth and survival of early juveniles of the marine sponge Hymeniacidon perlevis were examined. The concentrations of four types of food elements [microalgae (Isochrysis galbana), photosynthetic bacteria (Rhodopseudomonas), Fe(3+) (FeCl(3)), and Si (Na(2)SiO(3))] were investigated for early H. perlevis juvenile growth. Interestingly, temperature changes have striking effects on juvenile growth. Juvenile sponges grow faster when they are shifted to higher temperatures (18 degrees C to 23 degrees C) than when they are shifted to lower temperatures (18 degrees C to 4 degrees C to 23 degrees C) or kept at a constant temperature (18 degrees C). Periodic water flow and light cycles favor early juvenile sponge growth. Light was found to be a key factor in the color loss of early H. perlevis juveniles. Overall, size (area) increased as much as 29 times for H. perlevis juveniles under the tested controlled conditions.


Assuntos
Poríferos/fisiologia , Animais , Comportamento Animal , Dieta , Larva , Iluminação , Poríferos/crescimento & desenvolvimento , Análise de Sobrevida , Temperatura , Fatores de Tempo , Movimentos da Água
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