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1.
Colloids Surf B Biointerfaces ; 245: 114262, 2024 Sep 18.
Article in English | MEDLINE | ID: mdl-39303383

ABSTRACT

Hydrogel-based tissue clearing technologies have shown significant promise for deep-tissue imaging and subcellular-level optical 3D reconstruction of whole organs. This study proposes a novel approach utilizing a deep eutectic solvent (DES) formulated with glucose and m-xylylene-diamine (MXDA) to create a highly efficient tissue-clearing hydrogel system named the passive hydrogel clearing system (PHCS). PHCS achieved efficient tissue clearing through a single-step tissue gelation process. The resulting hydrogel-tissue complex exhibited thermoreversible properties, transitioning into a sol state upon heating and vice versa upon cooling. Notably, PHCS enabled media embedding, facilitating immunofluorescence histopathology. Additionally, the system demonstrated compatibility with various fluorescent probes, particularly lipophilic dyes. Our study successfully employed PHCS for the reconstruction of vascular structures within the intestine, enabling the generation of a 3D pathology model. These findings suggest that PHCS is a promising novel method for fabricating hydrogels for tissue clearing and holds great potential for application as a mounting medium for morphological imaging.

2.
Macromol Rapid Commun ; : e2400515, 2024 Aug 09.
Article in English | MEDLINE | ID: mdl-39122478

ABSTRACT

The utilization of (cationic) reversible addition-fragmentation chain transfer (RAFT) polymerization in photoinduced three-dimensional (3D) printing has emerged as a robust technique for fabricating a variety of stimuli-responsive materials. However, methods for precisely adjusting the mechanical properties of these materials remain limited, thereby constraining their broader applicability. In this study, a facile way is introduced to modulate the mechanical properties of 3D printed objects by mixing two chain transfer agents (CTAs) within a radical-promoted cationic RAFT (RPC-RAFT) polymerization-based 3D printing process. Through systematic investigations employing tensile testing and dynamic mechanical analysis (DMA), the influence of CTA concentration and molar ratio between two CTAs on the mechanical behavior of the printed objects are explored. These findings demonstrate that higher concentrations of CTAs or a greater molar ratio of the more active CTA within the mixed CTAs result in decreased Young's modulus and glass transition temperatures of the printed objects. Moreover, the tensile failure strain increased with the increasing CTA content, i.e., the samples became more ductile. This methodology broadens the toolbox available for tailoring the mechanical properties of 3D printed materials.

3.
Mater Today Bio ; 26: 101090, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38800564

ABSTRACT

Hyperpigmentation (HP) is an unfavorable skin disease that typically caused by injury, inflammation, or photoaging and leads to numerous physical and psychological issues in patients. Recently, development and application of natural whitening substances, particularly compound curcumin (CUR), is one of the most prevalent treatments for HP. However, it is still a formidable challenge to improve the percutaneous delivery of CUR due to its inadequate solubility in water and excellent barrier function of skin. To overcome the limitations of conventional delivery and increase the percutaneous absorption of CUR, the efficient delivery of CUR is urgently required. Herein, we developed a new malic acid-sorbitol deep eutectic solvent (MS/DES) gel microneedle loaded with CUR as a transdermal delivery system for HP treatment. The MS/DES gel produces three-dimensional (3D) network structure by self-assembly of hydrogen bond interactions, which conferred the CUR-MS/DES-GMN with sufficient mechanical properties to successfully penetrate skin tissue while also helping to enhance the drug's release rate. The CUR-MS/DES-GMN exhibit high biocompatibility and mechanical property in vivo of mice. The zebrafish experiments also show that CUR-MS/DES gel has significant effect of anti-pigmentation. Therefore, the designed CUR-MS/DES-GMN system provides a novel strategy for HP treatment based on self-assembly of naturally molecules.

4.
J Immunol ; 212(3): 397-409, 2024 Feb 01.
Article in English | MEDLINE | ID: mdl-38088801

ABSTRACT

SHP-1 (Src homology region 2 domain-containing phosphatase 1) is a well-known negative regulator of T cells, whereas its close homolog SHP-2 is the long-recognized main signaling mediator of the PD-1 inhibitory pathway. However, recent studies have challenged the requirement of SHP-2 in PD-1 signaling, and follow-up studies further questioned the alternative idea that SHP-1 may replace SHP-2 in its absence. In this study, we systematically investigate the role of SHP-1 alone or jointly with SHP-2 in CD8+ T cells in a series of gene knockout mice. We show that although SHP-1 negatively regulates CD8+ T cell effector function during acute lymphocytic choriomeningitis virus (LCMV) infection, it is dispensable for CD8+ T cell exhaustion during chronic LCMV infection. Moreover, in contrast to the mortality of PD-1 knockout mice upon chronic LCMV infection, mice double deficient for SHP-1 and SHP-2 in CD8+ T cells survived without immunopathology. Importantly, CD8+ T cells lacking both phosphatases still differentiate into exhausted cells and respond to PD-1 blockade. Finally, we found that SHP-1 and SHP-2 suppressed effector CD8+ T cell expansion at the early and late stages, respectively, during chronic LCMV infection.


Subject(s)
Lymphocytic Choriomeningitis , Lymphocytic choriomeningitis virus , Animals , Mice , CD8-Positive T-Lymphocytes/metabolism , Mice, Inbred C57BL , Mice, Knockout , Programmed Cell Death 1 Receptor/metabolism , T-Cell Exhaustion
5.
Exp Gerontol ; 185: 112347, 2024 01.
Article in English | MEDLINE | ID: mdl-38097054

ABSTRACT

Type 2 diabetes (T2D) is a common chronic disease, characterized by persistent hyperglycemia and insulin resistance. This disorder is associated with decreased bone quality and an elevated risk of bone fractures. However, evidence on the relationship between systemic metabolic change and the development of type 2 diabetic osteoporosis (T2DOP) remains elusive. Herein, we investigate the changes of bone metabolites with bone loss in db/db mice (an animal model of T2DOP exhibited bone loss with age progression), and explore the potential metabolic mechanism underlying type 2 diabetes and osteoporosis. C57BKS male mice were distributed in four groups, consisting six mice in each group: 8w m/m, 24w m/m, 8w db/db and 24w db/db. Bone morphometric and biomechanical parameters of db/db mice were analyzed by micro-CT and materials tester, it was found that 24w db/db mice showed severe bone loss and decreased bone tissue hardness compared with misty/misty littermates. The tibia of misty/misty mice (8 weeks, 24 weeks) and db/db mice (8 weeks, 24 weeks) were screened for differential metabolites by UPLC-Orbitrap MS. Ninety-eight metabolites were identified (35 and 63 metabolites are associated with early staged and late staged, respectively), consisting of amino acids, fatty acyls, and nucleotides. Notably, fatty acyls (such as 18-HEPE, 16(17)-EpDPE, arachidonic acid) and glycerophospholipids (such as phosphocholines (PC) (O-10:1(9E)/0:0), PC (O-16:1(9E)/0:0) [U] and phosphatidylethanolamines (PE) (P-16:0/0:0)) were significantly increased, and metabolites of amino acid pathway (such as l-glutamine, proline, phenylalanine) showed a downregulation trend. Dysregulation of lipid and glutathione pathways is the major contributor to progression of T2DOP in C57BKS mice.


Subject(s)
Diabetes Mellitus, Type 2 , Hyperglycemia , Insulin Resistance , Osteoporosis , Male , Mice , Animals , Diabetes Mellitus, Type 2/complications , Diabetes Mellitus, Type 2/metabolism , Metabolome , Osteoporosis/etiology , Amino Acids
6.
Sci Rep ; 13(1): 15901, 2023 Sep 23.
Article in English | MEDLINE | ID: mdl-37741848

ABSTRACT

Recent studies have shown great performance of Transformer-based models in long-term time series forecasting due to their ability in capturing long-term dependencies. However, Transformers have their limitations when training on small datasets because of their lack in necessary inductive bias for time series forecasting, and do not show significant benefits in short-time step forecasting as well as that in long-time step as the continuity of sequence is not focused on. In this paper, efficient designs in Transformers are reviewed and a design of decomposing residual convolution neural networks or DRCNN is proposed. The DRCNN method allows to utilize the continuity between data by decomposing data into residual and trend terms which are processed by a designed convolution block or DR-Block. DR-Block has its strength in extracting features by following the structural design of Transformers. In addition, by imitating the multi-head in Transformers, a Multi-head Sequence method is proposed such that the network is enabled to receive longer inputs and more accurate forecasts are obtained. The state-of-the-art performance of the presented model are demonstrated on several datasets.

7.
J Med Virol ; 95(8): e28997, 2023 08.
Article in English | MEDLINE | ID: mdl-37537950

ABSTRACT

During March 2022 to January 2023, two Omicron waves hit Shanghai and caused a massive number of reinfections. To better understand the incidence and clinical characteristics of SARS-CoV-2 reinfection in Shanghai, China, we conducted a multicenter cohort study. COVID-19 patients first infected with BA.2 (March 1, 2022-May 23, 2022) who were quarantined in Huashan Hospital, Renji Hospital, and Shanghai Jing'an Central Hospital were followed up for reinfection from June 1, 2022 to January 31, 2023. Of 897 primary infections, 148 (16.5%) experienced reinfection. Incidence rate of reinfection was 0.66 cases per 1000 person-days. Female gender (adjusted odds ratio [aOR]= 2.19, 95% confidence interval [CI]: 1.29-3.83) was a risk factor for reinfection. The four most common symptoms of reinfections during the circulation of BA.5 sublineages were cough (62.59%), sore throat (54.42%), fatigue (48.98%), and fever (42.57%). Having received a booster vaccination was not associated with reduced severity of reinfection in comparison with not having received booster vaccination. After matched 1:1 by age and sex, we found that reinfections with BA.5 sublineages had significantly lower occurrence and severity of fever, fatigue, sore throat, and cough, as compared to primary infections with BA.5 sublineages. SARS-CoV-2 Omicron reinfections were less severe than Omicron primary infections during the circulation of the same subvariant. Protection offered by both vaccination and previous infection was poor against SARS-CoV-2 reinfection.


Subject(s)
COVID-19 , Pharyngitis , Female , Humans , China/epidemiology , Cohort Studies , Cough , COVID-19/epidemiology , Fatigue , Fever , Incidence , Pain , Reinfection/epidemiology , SARS-CoV-2 , Male
8.
Int J Geriatr Psychiatry ; 38(6): e5944, 2023 06.
Article in English | MEDLINE | ID: mdl-37260087

ABSTRACT

OBJECTIVES: Cognitive frailty combines physical frailty and cognitive impairment in the absence of dementia. The prompt detection of cognitive frailty and early implementation of preventive interventions may reduce the incidence of dementia. However, intervention studies of exergaming in older adults with cognitive frailty are scant. Therefore, we aim to investigate the effectiveness of exergaming on cognitive functions and loneliness among older adults with cognitive frailty. DESIGN: Quasi-experimental design. METHODS: Participants were recruited from four community settings. The experimental group participated in two 40-min group exergaming sessions weekly for eight weeks; the control group received usual care. The outcome measures were the Montreal Cognitive Assessment (MoCA) and the Chinese Version of the Loneliness Scale. Analyses of covariance were conducted to analyze whether exergaming influenced participants' cognitive functions and loneliness. In addition, the effect size of the posttest of the experimental group relative to its baseline value was calculated to determine the effectiveness of the intervention. RESULT: 69 older adults with cognitive frailty were included, and 35 and 34 were assigned to the experimental and control groups, respectively. The exergaming effectively improved the cognitive function of older adults with cognitive frailty. CONCLUSIONS: Exergaming interventions can effectively improve the cognitive functions of older adults with cognitive frailty but do not positively affect loneliness. We provide evidence to healthcare workers to apply exergaming interventions for older adults with cognitive frailty to improve cognitive function.


Subject(s)
Dementia , Frailty , Humans , Aged , Loneliness/psychology , Exergaming , Cognition
9.
Molecules ; 28(8)2023 Apr 20.
Article in English | MEDLINE | ID: mdl-37110834

ABSTRACT

Increasing the yield and purity of B-phycoerythrin (B-PE) can improve the economic state of microalgae industrial processing. One method of cost reduction involves the recovery of remaining B-PE from wastewater. In this study, we developed a chitosan (CS)-based flocculation technique for the efficient recovery of B-PE from a low concentration of phycobilin in wastewater. We investigated the effects of the molecular weight of chitosan, B-PE/CS mass ratio, and solution pH on the flocculation efficiency of CS and the effects of phosphate buffer concentration and pH on the recovery rate of B-PE. The maximum flocculation efficiency of CS, recovery rate, and purity index of B-PE were 97.19% ± 0.59%, 72.07% ± 1.37%, and 3.20 ± 0.025 (drug grade), respectively. The structural stability and activity of B-PE were maintained during the recovery process. Economic evaluation revealed that our CS-based flocculation method is more economical than the ammonium sulfate precipitation method is. Furthermore, the bridging effect and electrostatic interaction play important roles in B-PE/CS complex flocculation process. Hence, our study provides an efficient and economical method to recover high-purity B-PE from a low concentration of phycobilin in wastewater, which promoted the application of B-PE as a natural pigment protein in food and chemical applications.

10.
Cell Mol Immunol ; 20(5): 512-524, 2023 05.
Article in English | MEDLINE | ID: mdl-36977779

ABSTRACT

CD8+ T cells play a central role in antiviral immune responses. Upon infection, naive CD8+ T cells differentiate into effector cells to eliminate virus-infected cells, and some of these effector cells further differentiate into memory cells to provide long-term protection after infection is resolved. Although extensively investigated, the underlying mechanisms of CD8+ T-cell differentiation remain incompletely understood. Themis is a T-cell-specific protein that plays critical roles in T-cell development. Recent studies using Themis T-cell conditional knockout mice also demonstrated that Themis is required to promote mature CD8+ T-cell homeostasis, cytokine responsiveness, and antibacterial responses. In this study, we used LCMV Armstrong infection as a probe to explore the role of Themis in viral infection. We found that preexisting CD8+ T-cell homeostasis defects and cytokine hyporesponsiveness do not impair viral clearance in Themis T-cell conditional knockout mice. Further analyses showed that in the primary immune response, Themis deficiency promoted the differentiation of CD8+ effector cells and increased their TNF and IFNγ production. Moreover, Themis deficiency impaired memory precursor cell (MPEC) differentiation but promoted short-lived effector cell (SLEC) differentiation. Themis deficiency also enhanced effector cytokine production in memory CD8+ T cells while impairing central memory CD8+ T-cell formation. Mechanistically, we found that Themis mediates PD-1 expression and its signaling in effector CD8+ T cells, which explains the elevated cytokine production in these cells when Themis is disrupted.


Subject(s)
CD8-Positive T-Lymphocytes , Lymphocytic Choriomeningitis , Mice , Animals , Lymphocytic choriomeningitis virus , Cell Differentiation , Cytokines/metabolism , Mice, Knockout , Mice, Inbred C57BL , Immunologic Memory , Intercellular Signaling Peptides and Proteins/metabolism
11.
Cell Death Discov ; 9(1): 67, 2023 Feb 17.
Article in English | MEDLINE | ID: mdl-36797242

ABSTRACT

Interleukin-35 (IL-35)-producing B cells (IL-35+B cells) play an important role in diseases, and the expansion of IL-35+ immune cells have been observed in inflammatory bowel disease (IBD). However, how IL-35+B cells function and the manner in which they perform their roles remain unclear. In this study, human samples and animal models were used to confirm the expansion of IL-35+B cells during IBD. In addition, by using il12a-/- and ebi3-/- mice, we demonstrated that the regulatory role of B cells in IBD depends on IL-35. Mechanically, IL-35+B cells can promote its own expansion through endocrine actions and depend on the transcription factor signal transducer and activator of transcription 3. Interestingly, we found that the diversity of intestinal microbes and expression of microbial metabolites decreased during IBD. IL-35+B cells promote the high expression of indoleacetic acid (IAA), and exogenous metabolite supplementation with IAA can further promote the expansion of IL-35+B cells and rescues the disease. This study provides a new concept for the regulatory model of B cells and a new approach for the treatment of IBD.

12.
Phys Med Biol ; 67(20)2022 10 07.
Article in English | MEDLINE | ID: mdl-36126658

ABSTRACT

Objective. To develop a simultaneous positron emission tomography-Optical (OPET) breast imaging dual-head PET subsystem, called DH-Mammo PET, for accurate, early diagnosis and efficacy assessment of breast cancer with high resolution and sensitivity.Approach. We developed a breast-dedicated PET based on LYSO crystal, silicon photomultiplier array and multi-voltage threshold sampling technique. It consists of two detector heads, each with a detection area of 216 mm × 145.5 mm. The distance between the detector heads is fixed at 120 mm. In order to extract coincidences and correct data, GPU-based software coincidence processing, random, scatter, normalization, gap-filling and attenuation corrections were applied in turn. The images were reconstructed using maximum likelihood expectation maximization with depth of interaction (DOI) modeling. The performance of DH-Mammo PET was evaluated referring to NEMA NU 4-2008, NU 2-2007 and Chinese industry recommended standard YY/T 1835-2022. Besides, several clinical patient images of DH-Mammo PET were compared with those of a whole-body PET/CT.Main results. The energy resolution was 14.5%, and time resolution was < 1.31 ns. Indicated by the22Na point source imaging, its spatial resolution was 2.60 mm (5.40 mm), 1.00 mm (1.04 mm), and 0.96 mm (0.93 mm) in theX,YandZdirections, respectively, using the system response matrix with (without) DOI modeling. Indicated by the Derenzo phantom imaging, the spatial resolution was ∼3.0 mm, <1.2 mm, and <1.2 mm in theX,YandZdirections. The system sensitivity was 6.87%, 4.89% and 3.37% with an energy window of 100-800, 250-750 and 350-650 keV, respectively. The scatter fraction was 26.43%, and the peak NECR was 162.6 kcps at 24.1 MBq for the modified rat-like phantom. As for the recovery coefficients, they ranged from 0.15 to 1.04 for rods between 1 and 5 mm obtained with a NEMA image quality phantom. The spill-over ratio for the air-filled and water-filled chamber was 0.05 and 0.11, respectively. DH-Mammo PET can provide more image details in clinical experiments and fulfil a fast scan with 60-120 s acquisition time.Significance. Good spatial resolution and high sensitivity of DH-Mammo PET would enable fast and accurate PET imaging of the breast. Besides, combining the DH-Mammo PET with the diffuse optical tomography would make full use of tumor metabolic imaging and tissue endogenous optical imaging, which would improve the accuracy of early clinical diagnosis of small lesions of breast cancers.


Subject(s)
Positron Emission Tomography Computed Tomography , Tomography, Optical , Animals , Electrons , Mammography , Phantoms, Imaging , Positron-Emission Tomography/methods , Rats , Water
13.
Nutr Cancer ; 74(10): 3747-3760, 2022.
Article in English | MEDLINE | ID: mdl-35838029

ABSTRACT

Although lung cancer treatment strategies have improved in recent years, the 5-year overall survival of non-small cell lung cancer (NSCLC) remains less than 15%. Chemotherapy is considered the most promising option in the comprehensive treatment of NSCLC. Fucoxanthin (FX) is a natural product derived from brown algae and has extensive applications in medicine. Previous studies reported that FX effectively inhibits the growth of NSCLC cells in vitro and in vivo. However, the mechanism underlying the anti-NSCLC effect of FX remains unknown. In this study, NSCLC cell lines and a xenograft nude mouse model were used to examine the anti-NSCLC activities of FX in vitro and in vivo. Network pharmacology analysis and inhibitors or activators of the PI3K/Akt signaling pathway were used to explore the anti-NSCLC mechanisms of FX. The results indicated that FX could inhibit proliferation, migration, and invasion, arrest cell cycle at the G0/G1 phase, and induce apoptosis of NSCLC cells in vitro. Additionally, FX suppressed tumor growth in vivo. The PI3K/Akt signaling pathway was found to be involved in the anti-NSCLC activity of FX. In conclusion, FX inhibits malignant biological behaviors of NSCLC by suppressing the phosphorylation of both PI3K and AKT, and subsequently inactivating PI3K/AKT signaling pathway.


Subject(s)
Carcinoma, Non-Small-Cell Lung , Lung Neoplasms , Animals , Carcinoma, Non-Small-Cell Lung/pathology , Cell Line, Tumor , Cell Proliferation , Humans , Lung Neoplasms/pathology , Mice , Phosphatidylinositol 3-Kinases/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Signal Transduction , Xanthophylls
14.
Exp Gerontol ; 166: 111897, 2022 09.
Article in English | MEDLINE | ID: mdl-35850279

ABSTRACT

Ultraviolet radiation (UVB) can result in photodamage to the skin and can seriously threaten health, particularly in the elderly. Oxidative stress and the inflammatory response have been shown to play a significant role in the process. In a previous study, we isolated, purified and identified a polysaccharide from the extract of Dendrobium huoshanense (DHPW1). In this study we evaluated the effect of DHPW1 on ameliorating the UVB photodamage of human immortalized keratinocytes (HaCaT). Cell proliferation and cell scratch assays were used to evaluate the viability of the HaCaT treated with DHPW1, and a fluorescent probe and Western blot analysis were used to examine the production of reactive oxygen species (ROS) and the expression of proinflammatory factors IL-1ß, IL-6, and NF-κB(p65). The results show that, compared with the control group (UVB irradiation only), DHPW1 significantly improved the viability of UVB-irradiated HaCaT and enhanced the migration rate of the cell scratch after 24 h. The scratch-healing rate reached 90 % after 36 h. DHPW1 also significantly inhibited UVB-induced oxidative stress and expression of proinflammatory factors . Compared with the control group, the production of ROS decreased by 49.11 %, and the relative protein expression of IL-6 and NF-κB(p65) decreased by up to 13.30 % and 31.02 %, respectively. It is concluded that DHPW1 can significantly improve viability and wound closure rate of UVB-irradiated HaCaT. In addition, it can reduce the expression of IL-1 and IL-6 by inhibiting the transcription of NF-κB(p65), thereby reducing inflammation and oxidative stress in UVB-irradiated HaCaT.


Subject(s)
NF-kappa B , Ultraviolet Rays , Aged , Cell Line , Humans , Interleukin-6/metabolism , Keratinocytes , NF-kappa B/metabolism , Reactive Oxygen Species/metabolism , Ultraviolet Rays/adverse effects
15.
BMC Complement Med Ther ; 22(1): 174, 2022 Jun 25.
Article in English | MEDLINE | ID: mdl-35752787

ABSTRACT

BACKGROUND: Polysaccharides from wampee have been reported to process various biological activities, while the relationship between structure and bioactivities has been barely addressed. Pectin, an abundant water-soluble polysaccharide in wampee, showed significant antioxidant activity, which was associated with the anti-melanogenic activity. Therefore, this study investigated the physicochemical characteristics and the anti-melanogenesis effect of pectin extracted from wampee fruit in A375 cells. METHODS: The physicochemical characterization of pectin from wampee fruit was investigated by gel chromatography (GCP), FT-IR spectroscopy, and NMR spectroscopy methods. The anti-melanogenesis effects and mechanism were evaluated by mushroom tyrosine enzyme and human melanin cell model in vitro. RESULTS: The results showed that a molecular weight of 5.271 × 105 Da wampee fruit pectin (WFP) were mainly composed of mannose (Man), ribose (Rib), rhamnose (Rha), glucuronic acid (Glc A), glucose (Glc), galacturonic acid (Gal A), galactose (Gal), and arabinose (Ara), which linked with →4)-ß-D-Galp-(1 → units. The current study revealed that WFP could significantly suppress mushroom TRY activity in vitro. Furtherly, WFP significantly reduced intracellular and extracellular melanin formation in A375 melanoma cells depending on the presence of alpha-melanocyte stimulating hormone (α-MSH). TRY activity was only inhibited in α-MSH treated A375 cells. Western blot analysis demonstrated that WFP reverse α-MSH induced melanogenesis in A375 melanoma cells, including in down-regulated TRY, TYRP-1, TYRP-2, MITF and CREB expressions. CONCLUSION: These results indicated that WFP could inhibit α-MSH induced melanogenesis in A375 melanoma cells via α-MSH/TRY pathway. In conclusion, these data provided a new perspective to annotate WFP anti-melanogenesis activity mechanism.


Subject(s)
Melanoma , alpha-MSH , Cell Line, Tumor , Fruit , Humans , Melanins , Microphthalmia-Associated Transcription Factor/metabolism , Monophenol Monooxygenase/metabolism , Pectins/pharmacology , Spectroscopy, Fourier Transform Infrared , alpha-MSH/metabolism , alpha-MSH/pharmacology
16.
Int J Biol Macromol ; 211: 441-449, 2022 Jun 30.
Article in English | MEDLINE | ID: mdl-35577191

ABSTRACT

Dendrobium huoshanense, a valuable traditional Chinese herb, is widely used to prolong life in China. Our study aims to characterize the structure and osteogenesis-promotion effects of a heteropolysaccharide component isolated from Dendrobium huoshanense (DHPW1). The structure of DHPW1 was characterized using gas chromatography-mass spectrometry and nuclear magnetic resonance, while its osteogenic activity was evaluated using MG-63 cells and zebrafish skulls. The results showed that the molecular weight of DHPW1 was 230 kDa and it was mainly composed of mannose and glucose. In addition, the DHPW1 backbone consisted of (1 â†’ 4)-linked-ß-D-Mannopyranosyl and (1 â†’ 4)-linked-ß-d-Glucopyranosyl. Furthermore, DHPW1 significantly increased ALP activity and mineralized nodule formation in MG-63 cells. DHPW1 in zebrafish skull models significantly enhanced the relative fluorescence intensity of bone mass and increased the degree of bone mineralization. These results suggested that the DHPW1 component in D. huoshanense has potential to promote osteogenesis.


Subject(s)
Dendrobium , Animals , Dendrobium/chemistry , Dietary Carbohydrates , Osteogenesis , Polysaccharides/chemistry , Zebrafish
17.
Tour Manag ; 90: 104485, 2022 Jun.
Article in English | MEDLINE | ID: mdl-35002005

ABSTRACT

While social media are effective means of communicating with adverse customer emotions during a crisis, it remains unclear how tourism organisations can respond to pandemic crisis on social media to prevent negative aftermaths. Using a set-theoretical approach, we investigate how COVID-19 response strategies and linguistic cues of responses are intertwined to evoke positive emotions among consumers. This study entails a qualitative content analysis of tourism organisations' COVID-19 announcements and a social media analytics approach that captures consumers' emotional reactions to these announcements via their Twitter replies. Our results extend some well-established findings in the tourism crisis literature by suggesting that combining innovative response strategy, argument quality, and assertive language can reinforce positive emotions during the COVID-19 crisis. Taking organisational characteristics into consideration, we suggest that young established hotels utilise innovative response strategies, whereas retrenchment response strategies for all types of restaurants should be avoided during the COVID-19 crisis.

18.
Exp Gerontol ; 155: 111550, 2021 11.
Article in English | MEDLINE | ID: mdl-34517082

ABSTRACT

Our previous study showed that the water-soluble heteropolysaccharide extracted from Gracilaria lemaneiformis (GLHP) has excellent anti-inflammation and anti-oxidant properties. This study explored the efficacy of GLHP against skin anti-photoaging in human immortalized keratinocytes (HaCaT) cells and BALB/c mice under UVB irradiation. Cell viability, antiapoptotic, reactive oxygen species (ROS) scavenging activity, mitochondrial membrane potential, and cell wound scratch assays were conducted, as well as assessment of inflammation markers and sun protection factors. The in vitro results showed that GLHP pretreatment significantly inhibited UVB-induced apoptosis, reversed the decrease of cell viability via downregulating the expression of apoptosis-related protein caspase-3, accelerated the migration of HaCaT cells, and promoted wound healing. Notably, the protective effect of GLHP may be associated with the scavenging of ROS and the decrease of mitochondrial membrane potential. Moreover, GLHP pretreatment significantly restrained the upregulation of iNOS (UVB-induced inflammation marker), suppressed the expression of P-ERK and NF-κB, and decreased the activity of MMPs, suggesting that it exerts the therapeutic effects by inhibiting the MAPK/NF-κB signal pathway. Results obtained after conducting the in vivo assay confirmed that GLHP could reverse the UVB-induced increase of epidermal thickness in BALB/c mice. In conclusion, this study shows that GLHP can be utilized as a safer resource in the manufacture of anti-aging cosmetics because it exerts excellent anti-photoaging effects.


Subject(s)
Gracilaria , Skin Aging , Animals , Humans , Keratinocytes , Mice , Mice, Inbred BALB C , Reactive Oxygen Species , Ultraviolet Rays/adverse effects
19.
Onco Targets Ther ; 13: 11711-11724, 2020.
Article in English | MEDLINE | ID: mdl-33235461

ABSTRACT

INTRODUCTION: Accumulating evidence has indicated that long noncoding RNAs (lncRNAs) are pivotal regulators involved in the pathogenesis of cancer; however, the molecular mechanism of LINC00339 in colorectal cancer (CRC) remains unclear. METHODS: The quantitative real-time polymerase chain reaction for the expression of LINC00339 and miR-378a-3p and Western blots for MED19 were performed. A dual-luciferase assay was used to investigate the interaction between LIN00339 and miR-378a-3p, as well as between miR-378a-3p and MED19. Cell proliferation was determined by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) and 5-ethynyl-2'-deoxyuridine (EdU) assay. The cell cycle was analyzed by propidium iodide staining followed by flow cytometry analysis. The wound-healing and transwell invasion assays were used to evaluate cell migration and invasion. RESULTS: The expression of LINC00339 was significantly upregulated in CRC cells and tissues, and high LINC00339 expression indicated an advanced tumor stage. Further experiments demonstrated that SP1 activated LINC00339 expression by binding to its promoter region. Luciferase activity and RNA pull-down assays demonstrated a direct interaction between LINC00339 and miR-378a-3p. miR-378a-3p expression was decreased in CRC samples and negatively correlated with LINC00339 expression in tumors. Gain- and loss-of-function assays indicated that LINC00339 contributed to cell proliferation, cell cycle progression, migration, and invasion, while miR-378a-3p reversed these effects. Furthermore, cotransfection of wild-type MED19 3'-UTR reporters and miR-378a-3p significantly reduced luciferase activity. MED19 mRNA and protein expression was inhibited and enhanced by miR-378a-3p and LINC00339, respectively. MED19 overexpression reversed the effect of miR-378a-3p on cellular processes. Moreover, LINC00339 promoted tumor growth in vivo and induced epithelial-mesenchymal transition (EMT) and activated the Wnt/ß-catenin signaling pathway in cells. CONCLUSION: Our findings demonstrate the regulatory role of the SP1/LINC00339/miR-378a-3p/MED19 axis in CRC tumorigenesis and provide novel insight into the molecular mechanism underlying CRC.

20.
Microbes Infect ; 22(3): 119-126, 2020 04.
Article in English | MEDLINE | ID: mdl-31678658

ABSTRACT

CD4+/CD8+ T cells play a major role in conferring immune protection against tuberculosis (TB), but it remains unknown how the immune responses of CD4+/CD8+ T cells exactly correlate with the clinical variables and disease statuses during anti-TB chemotherapy. To address this, several major immune parameters of CD4+/CD8+ T cells in peripheral blood derived from pulmonary TB patients and healthy volunteers were evaluated. We observed that active TB infection induced lower CD3+ T cell and CD4+ T cell levels but higher CD8+T cell levels, while anti-TB chemotherapy reversed these effects. Also, anti-TB treatment induced enhanced production of IL-2 and IFN-γ but reduced expression of IL-10 and IL-6. Moreover, the dynamic changes of CD3, CD4, and CD8 levels did not show a significant association with sputum smear positivity. However, the frequencies of IL-2+CD4+ or IL-10 + CD4+ T effector subpopulation or IL-1ß production in peripheral blood showed significant difference between patients positive for sputum smear and patients negative for sputum smear after anti-TB treatment. These findings implicated that recovery of Th1/CD8+T cell effector levels might be critical immunological events in pulmonary TB patients after treatment and further suggested the importance of these immunological parameters as potential biomarkers for prediction of TB progress and prognosis.


Subject(s)
Antitubercular Agents/therapeutic use , CD8-Positive T-Lymphocytes/immunology , Th1 Cells/immunology , Tuberculosis, Pulmonary/drug therapy , Tuberculosis, Pulmonary/immunology , Adult , Asian People/ethnology , CD4-Positive T-Lymphocytes/immunology , China , Female , Humans , Interferon-gamma/immunology , Interleukin-10/immunology , Interleukin-1beta/blood , Interleukin-1beta/immunology , Interleukin-6/immunology , Male , Mycobacterium tuberculosis , Tuberculosis, Pulmonary/ethnology , Young Adult
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