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1.
Sci Bull (Beijing) ; 2024 Apr 29.
Article in English | MEDLINE | ID: mdl-38777682

ABSTRACT

Lunar exploration is deemed crucial for uncovering the origins of the Earth-Moon system and is the first step for advancing humanity's exploration of deep space. Over the past decade, the Chinese Lunar Exploration Program (CLEP), also known as the Chang'e (CE) Project, has achieved remarkable milestones. It has successfully developed and demonstrated the engineering capability required to reach and return from the lunar surface. Notably, the CE Project has made historic firsts with the landing and on-site exploration of the far side of the Moon, along with the collection of the youngest volcanic samples from the Procellarum KREEP Terrane. These achievements have significantly enhanced our understanding of lunar evolution. Building on this success, China has proposed an ambitious crewed lunar exploration strategy, aiming to return to the Moon for scientific exploration and utilization. This plan encompasses two primary phases: the first crewed lunar landing and exploration, followed by a thousand-kilometer scale scientific expedition to construct a geological cross-section across the lunar surface. Recognizing the limitations of current lunar exploration efforts and China's engineering and technical capabilities, this paper explores the benefits of crewed lunar exploration while leveraging synergies with robotic exploration. The study refines fundamental lunar scientific questions that could lead to significant breakthroughs, considering the respective engineering and technological requirements. This research lays a crucial foundation for defining the objectives of future lunar exploration, emphasizing the importance of crewed missions and offering insights into potential advancements in lunar science.

2.
Food Chem ; 449: 139310, 2024 Aug 15.
Article in English | MEDLINE | ID: mdl-38608612

ABSTRACT

This study investigated the effects of the conjugate reaction sequences of whey protein concentrate (WPC), epigallocatechin gallate (EGCG) and dextran (DEX) on the structure and emulsion properties of conjugates and the bioaccessibility of astaxanthin (AST). Two types of ternary covalent complexes were synthesised using WPC, EGCG and DEX, which were regarded as emulsifiers of AST nanoemulsions. Results indicated that the WPC-DEX-EGCG conjugate (referred to as 'con') exhibits a darker SDS-PAGE dispersion band and higher contents of α-helix (6%), ß-angle (24%) and random coil (32%), resulting in a greater degree of unfolding structure and fluorescence quenching. These findings suggested WPC-DEX-EGCG con had the potential to exhibit better emulsification properties than WPC-EGCG-DEX con. AST encapsulation efficiency (76.22%) and bioavailability (31.89%) also demonstrated the superior performance of the WPC-DEX-EGCG con emulsifier in nanoemulsion delivery systems. These findings indicate that altering reaction sequences changes protein conformation, enhancing the emulsification properties and bioavailability of AST.


Subject(s)
Biological Availability , Catechin/analogs & derivatives , Emulsifying Agents , Emulsions , Whey Proteins , Xanthophylls , Xanthophylls/chemistry , Emulsions/chemistry , Emulsifying Agents/chemistry , Whey Proteins/chemistry , Animals , Catechin/chemistry , Dextrans/chemistry , Male , Rats , Rats, Sprague-Dawley
3.
Neuropeptides ; 105: 102428, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38583362

ABSTRACT

RNA methylation can epigenetically regulate learning and memory. However, it is unclear whether RNA methylation plays a critical role in the pathophysiology of Vascular dementia (VD). Here, we report that expression of the fat mass and obesity associated gene (FTO), an RNA demethylase, is downregulated in the hippocampus in models of VD. Through prediction and dual-luciferase reporters validation studies, we observed that miRNA-711 was upregulated after VD and could bind to the 3'-untranslated region of FTO mRNA and regulate its expression in vitro. Methylated RNA immunoprecipitation (MeRIP)-qPCR assay and functional study confirmed that Syn1 was an important target gene of FTO. This suggests that FTO is an important regulator of Syn1. FTO upregulation by inhibition of miR-711 in the hippocampus relieves synaptic association protein and synapse deterioration in vivo, whereas FTO downregulation by miR-711 agomir in the hippocampus leads to aggravate the synapse deterioration. FTO upregulation by inhibition of miR-711 relieves cognitive impairment of rats VD model, whereas FTO downregulation by miR-711 deteriorate cognitive impairment. Our findings suggest that FTO is a regulator of a mechanism underlying RNA methylation associated with spatial cognitive dysfunction after chronic cerebral hypoperfusion.


Subject(s)
Alpha-Ketoglutarate-Dependent Dioxygenase FTO , Cognitive Dysfunction , Hippocampus , MicroRNAs , Rats, Sprague-Dawley , Alpha-Ketoglutarate-Dependent Dioxygenase FTO/metabolism , Alpha-Ketoglutarate-Dependent Dioxygenase FTO/genetics , Animals , Male , MicroRNAs/metabolism , MicroRNAs/genetics , Hippocampus/metabolism , Cognitive Dysfunction/metabolism , Cognitive Dysfunction/etiology , Rats , Methylation , Dementia, Vascular/metabolism , Dementia, Vascular/genetics , Disease Models, Animal , RNA Methylation
4.
Langmuir ; 39(36): 12762-12773, 2023 Sep 12.
Article in English | MEDLINE | ID: mdl-37642387

ABSTRACT

Formaldehyde (HCHO) poses a grave threat to human health because of its toxicity, but its accurate, sensitive, and rapid detection in aqueous solutions remains a major challenge. This study proposes a novel electrochemical sensor composed of a graphene-based electrode that is prepared via laser induction technology. The precursor material, polyimide, is modified via the metal ion exchange method, and the detective electrode is coated with graphene and silver nanoparticles. And the special structure of graphene-coated Ag was demonstrated using scanning electron microscopy (SEM) and high-resolution transmission electron microscopy (HRTEM), and X-ray diffraction (XRD), Fourier transform infrared (FT-IR), and X-ray photoelectron spectroscopy (XPS) results show that graphene provides more sites for Ag NRs to be exposed and increases the surface area of contact between the solution and the detection object. In addition, differential pulse voltammetry (DPV) analysis exhibits high linearity over the HCHO concentration range from 0.05 to 5 µg/mL, with a detection limit of 0.011 µg/mL (S/N = 3). The Ag NPs in the electrochemical reaction will adsorb the intermediate •CO and •OH, catalyze their combination, and finally convert to CO2 and H2O, respectively. A microdetection device, specially designed for use with commercial micro-workstations, is employed to fully demonstrate the practical application of the electrode, which paves a way for developing formaldehyde electrochemical sensors.

5.
Front Psychiatry ; 13: 963092, 2022.
Article in English | MEDLINE | ID: mdl-36061303

ABSTRACT

Brain structural and functional abnormalities have been shown to be involved in the neurobiological underpinnings of bulimia nervosa (BN), while the mechanisms underlying this dysregulation are unclear. The main goal of this investigation was to explore the presence of brain structural alterations and relevant functional changes in BN. We hypothesized that BN patients had regional gray matter volume abnormalities and corresponding resting-state functional connectivity (rsFC) changes compared with healthy controls. Thirty-one BN patients and twenty-eight matched healthy controls underwent both high-resolution T1-weighted magnetic resonance imaging (MRI) and resting-state functional MRI. Structural analysis was performed by voxel-based morphometry (VBM), with subsequent rsFC analysis applied by a seed-based, whole-brain voxelwise approach using the abnormal gray matter volume (GMV) region of interest as the seed. Compared with the controls, the BN patients showed increased GMV in the left medial orbitofrontal cortex (mOFC). The BN patients also exhibited significantly increased rsFC between the left mOFC and the right superior occipital gyrus (SOG) and decreased rsFC between the left mOFC and the left precentral gyrus, postcentral gyrus, and supplementary motor area (SMA). Furthermore, the z values of rsFC between the left mOFC and right SOG was positively correlated with the Dutch Eating Behavior Questionnaire-external eating scores. Findings from this investigation further suggest that the mOFC plays a crucial role in the neural pathophysiological underpinnings of BN, which may lead to sensorimotor and visual regions reorganization and be related to representations of body image and the drive behind eating behavior. These findings have important implications for understanding neural mechanisms in BN and developing strategies for prevention.

6.
Chemosphere ; 246: 125772, 2020 May.
Article in English | MEDLINE | ID: mdl-31901658

ABSTRACT

Excessive fluoride (F) ingestion via drinking water interfered with spermatogenesis and lowered sperm quality of human and animals. However, it is still unclear why the effects of fluoride on sperm quality focus on mostly sperm motility rather than sperm count. The objective of this study is to investigate the potential relationship between alteration in the structure and function of sperm flagellum and fluoride exposure in the environment. 40 male mice were allocated to four groups which were treated with 0, 25, 50, 100 mg/L NaF deionized water, respectively, for 8 weeks continuously. The testicular morphology, ultra-structure of fibrous sheath and axoneme of sperm flagellum, and eleven key function genes Akap3, Akap4, Dnah1, Eno4, Cfap43, Cfap44, Hydin, Spef2, Spag6, Spag16, and Cfap69 were examined by histology, transmission electron microscopy, and real-time PCR methods respectively. The results displayed that fluoride damaged the typical "9 + 2″ microtubule structure including fibrous sheathes and axoneme of sperm flagellum in testes of mice. Furthermore, the mRNA and protein expression levels of AKAP3 and AKAP4 related to fibrous sheathes formation, and CFAP43, CFAP44 and HYDIN in axoneme were down-regulated by fluoride exposure. Taken together, we revealed that fluoride altered the structures of the fibrous sheathes and axonemal in sperm flagellum via down-regulating the mRNA and protein expression levels of AKAP3, AKAP4, CFAP43, CFAP44, and HYDIN, which may be one of the reasons that fluoride lowered sperm quality and male reproductive function.


Subject(s)
Fluorides/toxicity , Sperm Tail/ultrastructure , Testis/metabolism , A Kinase Anchor Proteins , Animals , Dyneins , Environmental Pollutants , Fluorides/metabolism , Humans , Infertility, Male , Male , Mice , Microtubule Proteins , Phenotype , RNA, Messenger/metabolism , Sperm Motility , Sperm Tail/drug effects , Spermatogenesis , Spermatozoa/metabolism
7.
Environ Pollut ; 256: 113438, 2020 Jan.
Article in English | MEDLINE | ID: mdl-31672359

ABSTRACT

It is very important to explore the potential harm and underlying mechanism of fluoride due to the extensive distribution and the significant health risks of fluoride in environment. The objective of this study to investigate whether fluoride can induce mitochondrial impairment and mitophagy in testicular cells. For this, 40 male mice were randomly divided into four groups treated with 0, 0.6, 1.2, 2.4 mM NaF deionized water, respectively, for 90 days continuously. The results showed that mitophagy was triggered by F in testicular tissues, especially in the Leydig cells by transmission electron microscopy and mitophagy receptor PHB2 locations by immunofluorescence. Furthermore, TM3 Leydig cells line was employed and treated with 0, 0.125, 0.25, and 0.5 mM NaF for 24 h. The mitochondrial function indicators and mitophagy maker PHB2, COX IV and regulator PINK1 in transcript and protein levels in Leydig cells were examined by the methods of qRT-PCR, western blotting, and immunofluorescence co-localization. The results showed that fluoride decreased the mitochondrial membrane potential with a concomitant increase in the number of lysosomes. Meanwhile, fluoride exposure also increased the expressions of PINK1 and PHB2 in TM3 Leydig cells. These results revealed that fluoride could induce mitochondrial impairment and excessive PINK1/Parkin-mediated mitophagy in testicular cells, especially in Leydig cells, which could contribute to the elucidation of the mechanisms of F-induced male reproductive toxicity.


Subject(s)
Environmental Pollutants/toxicity , Fluorides/toxicity , Leydig Cells/physiology , Mitophagy , Protein Kinases/metabolism , Animals , Fluorides/metabolism , Humans , Leydig Cells/metabolism , Male , Membrane Potential, Mitochondrial , Mice , Mitochondria/metabolism , Prohibitins , Ubiquitin-Protein Ligases
8.
Genes Genomics ; 41(10): 1173-1181, 2019 10.
Article in English | MEDLINE | ID: mdl-31313106

ABSTRACT

BACKGROUND: Synonymous codon usage bias is noticed in the genome of every organism, influenced by mutation pressure and natural selection. The analysis of codon usage pattern in Porphyra umbilicalis chloroplast genome are inferred while previous study focused on codon bias in nuclear genome. OBJECTIVE: To develop a better understanding of the factors affecting synonymous codon usage, codon usage patterns and nucleotide composition of 150 genes in P. umbilicalis cp genome, and provide a theoretical basis for genetic modification of chloroplast genome. METHODS: In this study, all codon usage bias parameters and nucleotide compositions were calculated by Python script, Codon W, DNA Star, CUSP of EMBOSS and Microsoft Excel. RESULTS: It shows that codon usage models are mainly influenced by compositional constraints under mutational pressure and synonymous codon prefers to use codons ending with A/T, comparing to C/G. The ENC value is slight low which shows the weak codon bias. For all coding genes of P. umbilicalis chloroplast genome except Photosystem I genes, a weak correlation between GC3 and GC12 suggests natural selection might play a significant role in synonymous codon usage bias. CONCLUSION: The codon usage bias in P. umbilicalis cp genome is low and in some way or other, influenced by natural selection, mutation pressure, nucleotide composition. Our results can provide a theoretical basis for codon modification of exogenous genes, accuracy of prediction about new members of chloroplast gene family and identification of unknown genome.


Subject(s)
Chloroplasts/genetics , Codon Usage/genetics , Genome, Chloroplast/genetics , Porphyra/genetics , Base Composition , Codon , Mutation , Photosystem I Protein Complex/genetics , Selection, Genetic
9.
J Agric Food Chem ; 67(18): 5240-5249, 2019 May 08.
Article in English | MEDLINE | ID: mdl-31008594

ABSTRACT

Fluoride is a widespread environmental pollutant that can induce low sperm quality and fertilizing ability; however, the underlying mechanism still remains unclear. Hence, we aimed to investigate the influence of fluoride on the sperm fertilizing ability via some key proteins in the epididymis. For this, 40 adult rats were assigned randomly into four groups. The control group was given distilled water, while the other three groups were given 25, 50, and 100 mg of NaF/L via drinking water for 56 days, respectively. After 1 day, epididymides were processed for sperm-egg binding, RNA extraction, western blot, and immunofluorescence analysis. Fluoride exposure reduced the ability of sperm to break down the egg cumulus cell layer. A further study revealed that fluoride altered the expression levels of genes and proteins related to acrosome reaction in vivo, including SPAM1, ACR, and PRSS21. However, fluoride only affected the expression of the ACR protein only in the epididymis but not in the testis. Fluoride also affected the expression levels of the membrane proteins CD9 and CD81 of epididymosomes in the epididymis. From the results, it can be concluded that fluoride exposure reduced the ability of sperm to break down the egg cumulus cell layer, which could be one of the reasons for decreased fertility ability in males treated with fluoride. These results provide some theoretical guidance and new ideas for treatments of low fertility, infertility, and other reproductive diseases.


Subject(s)
Acrosin/metabolism , Cell Adhesion Molecules/metabolism , Epididymis/drug effects , Fluorides/pharmacology , Hyaluronoglucosaminidase/metabolism , Serine Endopeptidases/metabolism , Spermatozoa/drug effects , Spermatozoa/physiology , Acrosin/genetics , Animals , Cell Adhesion Molecules/genetics , Epididymis/metabolism , Fertilization/drug effects , Hyaluronoglucosaminidase/genetics , Male , Rats , Rats, Sprague-Dawley , Serine Endopeptidases/genetics , Testis/drug effects , Testis/metabolism
10.
BMC Public Health ; 19(1): 11, 2019 Jan 03.
Article in English | MEDLINE | ID: mdl-30606149

ABSTRACT

BACKGROUND: The post-disaster mental health crisis intervention (MHCI) system in China remains immature and unsystematic. We aim to report the perceptions of a large sample of MHCI workers and government administrators and provide recommendations for developing a national mental health disaster response management plan in China. METHODS: An in-depth qualitative study was conducted, collecting data from 20 focus-group discussions and 25 key stakeholder interviews. These recruited participants who had been involved in different types of disaster rescue across 7 provinces/cities where disasters have recently occurred. We used thematic analysis to analyze the data and relevant findings were extracted for policy recommendation. RESULTS: Mental health workers' perspectives were examined in detailed according to four core themes: forms of organization, intervention pathway, intervention strategy and technique, and public health information. Post-disaster MHCI should be approached in teams that are integrated with emergency medicine systems, and be led by unified command management. All levels of local health and family planning commission should prepare post-disaster MHCI work plans and build response teams/emergency centres. Future training for MHCI workers should focus on: building a sense of trust within the team; clarifying each member's role; strengthening the screening, assessment and referrals training for psychological professionals; and providing psychological intervention training for Chinese psychiatrists. It is necessary to set up guiding principles for disaster research ethics, mental health rehabilitation and media interaction. CONCLUSIONS: Through exploring and analyzing the perceptions of current disaster response mental health workers and government administrators, our findings provide essential recommendations for developing a national to county level post-disaster MHCI emergency management plan and can guide the formulation of relevant laws and regulation in China.


Subject(s)
Attitude of Health Personnel , Disaster Planning/organization & administration , Health Personnel/psychology , Mental Health Services , Adult , China , Female , Focus Groups , Health Personnel/statistics & numerical data , Humans , Male , Middle Aged , Qualitative Research
11.
BMC Psychiatry ; 18(1): 26, 2018 01 30.
Article in English | MEDLINE | ID: mdl-29378562

ABSTRACT

BACKGROUND: This forms the first study of a group-based psychoeducation program for inpatients following remission of a manic episode in patients suffering from bipolar I disorder in a Chinese population. The aim was to explore the patient's perspectives of the program and their suggestions regarding ways to improve the intervention in the future. METHODS: Semi-structured and in-depth interviews were conducted with 15 participants who had participated in 8 sessions of a group psychoeducation program over 2 weeks. The verbatim transcripts of those interviews were analysed using thematic analysis. RESULTS: Five themes emerged from the data, including the patients' perception of participating in the program, their perception of the setting, perception of participating in a group program, perception of the learning content and of the outcome of participating in the program. CONCLUSIONS: The results presented here describe how the short-term group psychoeducation program was experienced by the patients. Recommendations are also offered to improve the setting, content, and delivery. Our findings provide evidence that the program is beneficial for manic patients with bipolar I disorder, and this intervention warrants further research especially in a Chinese population. If these benefits are confirmed in future studies, this program could be incorporated into routine psychiatric inpatient care in China.


Subject(s)
Bipolar Disorder/therapy , Mental Health Services , Patient Satisfaction , Psychotherapy, Group , Adolescent , Adult , Bipolar Disorder/psychology , China , Female , Hospitalization , Humans , Male , Middle Aged , Perception , Qualitative Research , Young Adult
12.
Rapid Commun Mass Spectrom ; 32(4): 306-310, 2018 Feb 28.
Article in English | MEDLINE | ID: mdl-29205593

ABSTRACT

RATIONALE: Although being out of equilibrium, biomolecules in organisms have the potential to approach isotope equilibrium locally because enzymatic reactions are intrinsically reversible. A rigorous approach that can describe isotope distribution among biomolecules and their apparent deviation from equilibrium state is lacking, however. METHODS: Applying the concept of distance matrix in graph theory, we propose that apparent local isotope equilibrium among a subset of biomolecules can be assessed using an apparent fractionation difference (|Δα|) matrix, in which the differences between the observed isotope composition (δ') and the calculated equilibrium fractionation factor (1000lnß) can be more rigorously evaluated than by using a previous approach for multiple biomolecules. We tested our |Δα| matrix approach by re-analyzing published data of different amino acids (AAs) in potato and in green alga. RESULTS: Our re-analysis shows that biosynthesis pathways could be the reason for an apparently close-to-equilibrium relationship inside AA families in potato leaves. Different biosynthesis/degradation pathways in tubers may have led to the observed isotope distribution difference between potato leaves and tubers. The analysis of data from green algae does not support the conclusion that AAs are further from equilibrium in glucose-cultured green algae than in the autotrophic ones. CONCLUSIONS: Application of the |Δα| matrix can help us to locate potential reversible reactions or reaction networks in a complex system such as a metabolic system. The same approach can be broadly applied to all complex systems that have multiple components, e.g. geochemical or atmospheric systems of early Earth or other planets.

13.
Proc Natl Acad Sci U S A ; 113(20): 5542-6, 2016 May 17.
Article in English | MEDLINE | ID: mdl-27140601

ABSTRACT

A three-dimensionally preserved 2-mm-long larva of the arthropod Leanchoilia illecebrosa from the 520-million-year-old early Cambrian Chengjiang biota of China represents the first evidence, to our knowledge, of such an early developmental stage in a short-great-appendage (SGA) arthropod. The larva possesses a pair of three-fingered great appendages, a hypostome, and four pairs of well-developed biramous appendages. More posteriorly, a series of rudimentary limb Anlagen revealed by X-ray microcomputed tomography shows a gradient of decreasing differentiation toward the rear. This, and postembryonic segment addition at the putative growth zone, are features of late-stage metanauplii of eucrustaceans. L. illecebrosa and other SGA arthropods, however, are considered representative of early chelicerates or part of the stem lineage of all euarthropods. The larva of an early Cambrian SGA arthropod with a small number of anterior segments and their respective appendages suggests that posthatching segment addition occurred in the ancestor of Euarthropoda.


Subject(s)
Arthropods/anatomy & histology , Biota , Larva/anatomy & histology , Animals , Arthropods/ultrastructure , China , Larva/ultrastructure , Tomography, X-Ray Computed
14.
Guang Pu Xue Yu Guang Pu Fen Xi ; 31(8): 2053-7, 2011 Aug.
Article in English | MEDLINE | ID: mdl-22007383

ABSTRACT

YxVO4: 0.01Dy3+ and Y0.99-x V04: 0.01Dy3+, xBi3+ phosphors were synthesized by chemical coprecipitation method. Their crystal structure, micromorphology and photoluminescence (PL) properties were investigated by X-ray diffraction (XRD), scan electron microscopy (SEM) and spectrofluorometer. YxVO4: 0.01Dy3+ and Y0.99--xVO4: 0.01Dy3+, xBi3+ phosphors have a broad excitation band from about 250 to 350 nm including a strongest peak at about 310 nm. Under its excitation, the emission spectra exhibits two sharp peaks, one of which centered at about 483 nm for 4F9/2-->6H15/2 transition of Dy3+ and the other at about 574 nm due to the 4F9/2-->6 H13/2 transition of Dy+. For YxVO4: 0.01Dy3+, (x = 0.94, 0.97, 0.99, 1.01, 1.03) phosphor, with increasing value of x, the body color of phosphor changes from yellow to white and the strongest peak in the excitation spectra shifts a little to shorter wavelength. It is detrimental to luminous intensity when Y3+ content deviates stoichiometric ratio. For Y0.99--x VO4: 0.01Dy3+, xBi3+ (x = 0.01, 0.05, 0.1, 0.15, 0.2, 0.25) phosphor, the samples have extraneous bismuth vanadium oxide phase except for the major tetragonal zircon structure when x > or = 0.20. With increasing value of x, the band edge in the excitation spectra shifts to longer wavelength, the excitation intensity and luminous intensity increase early and decrease late. When the value of x is 0.01, the intensities increase evidently. In addition, the influence of Y3+ or Bi3+ on the color temperature of emission and micromorphology of YVO4:Dy3+ is slight.

15.
Chem Commun (Camb) ; 46(29): 5250-2, 2010 Aug 07.
Article in English | MEDLINE | ID: mdl-20574560

ABSTRACT

Adding a small amount of commercial GeO(2) into aqueous suspension significantly enhanced the photocatalytic activity of titania-based photocatalysts for the degradation of dyes.


Subject(s)
Germanium/chemistry , Photolysis , Titanium/chemistry , Catalysis , Suspensions/chemistry
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