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1.
Chem Commun (Camb) ; 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38973675

RESUMO

The solvothermal reaction of CuSO4·5H2O and a chiral R-pempH2 ligand (molar ratio 6 : 1) first forms the metastable intermediate [Cu24(OH)20(R-pempH)8(SO4)10(H2O)10.5]·35H2O (1), followed by the formation of the stable phase [Cu2(OH)(R-pempH)(SO4)(H2O)]·H2O (2). Compound 1 displays a novel 3D open-framework structure containing Cu12 cluster nodes and sulfate links, which can be converted to the layered compound 2. We also investigated the photothermal effects of both compounds.

2.
Small Methods ; : e2400671, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38803310

RESUMO

Cyclometalated iridium (Ir) complexes demonstrate impressive capabilities across a range of fields, including biology and photocatalysis, due to their tunable optical characteristics and structure flexibility. However, generating upconversion luminescence of Ir complexes under near-infrared light excitation is challenging. Herein, by employing lanthanide-doped upconversion nanoparticles (UCNPs) as the sensitizer, a new strategy is demonstrated to gain upconversion luminescence of Ir complexes via triplet energy transfer. This design relies on a rationally designed hybrid of core-shell structured NaYbF4:Tb@NaTbF4 UCNPs and new Ir phosphonate complexes, in which UCNPs can migrate upconverted energy to the surface of nanoparticles through Tb3+-mediated energy migration and then sensitize the upconversion luminescence of Ir complexes upon 980 nm excitation. Both experimental and theoretical investigations highlight the significance of triplet energy transfer from excited Tb3+ ions to the triplet state of Ir complexes in the sensitization of upconversion luminescence of Ir complexes. These findings may open exciting avenues for fabricating hybrid Ir materials with new functions and driving the development of UCNP-based nanomaterials.

3.
Mol Biol Rep ; 51(1): 386, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38441676

RESUMO

BACKGROUND: There was significant difference in muscle development between fat-type and lean-type pig breeds. METHODS AND RESULTS: In current study, transcriptome analysis and bioinformatics analysis were used to compare the difference in longissimus dorsi (LD) muscle at three time-points (38 days post coitus (dpc), 58 dpc, and 78 dpc ) between Huainan (HN) and Large white (LW) pig breeds. A total of 24500 transcripts were obtained in 18 samples, and 2319, 2799, and 3713 differently expressed genes (DEGs) were identified between these two breeds at 38 dpc, 58 dpc, and 78 dpc, respectively. And the number and foldchange of DEGs were increased, the alternative splice also increased. The cluster analysis of DEGs indicated the embryonic development progress of LD muscle between these two breeds was different. There were 539 shared DEGs between HN and LW at three stages, and the top-shared DEGs were associated with muscle development and lipid deposition, such as KLF4, NR4A1, HSP70, ZBTB16 and so on. CONCLUSIONS: The results showed DEGs between Huainan (HN) and Large white (LW) pig breeds, and contributed to the understanding the muscle development difference between HN and LW, and provided basic materials for improvement of meat quality.


Assuntos
Biologia Computacional , Perfilação da Expressão Gênica , Feminino , Gravidez , Suínos/genética , Animais , Análise por Conglomerados , Desenvolvimento Embrionário , Obesidade , Vitaminas
4.
Dalton Trans ; 53(9): 4291-4298, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38345325

RESUMO

Studying the effect of morphology on the circularly polarized luminescence (CPL) of chiral molecular materials is important for the development of CPL-active materials for applications. Herein, we report that the morphology of Gd(NO3)3/R-,S-AnempH2 [AnempH2 = (1-anthrylethylamino)methylphosphonic acid] assemblies can be controlled by solvent modulation to form spiral bundles Gd(R-,S-AnempH)3·2H2O (R-,S-1), crystals Gd(R-,S-AnempH)3·2H2O (R-,S-2) and spindle-shaped particles Gd(R-,S-AnempH)3·3H2O·0.5DMF (R-,S-3) with similar chain structures. Interestingly, R-,S-1 are CPL active and show the highest value of dissymmetric factor among the three pairs of enantiomers (|glum| = 2.1 × 10-3), which is 2.8 times larger than that of R-,S-2, while R-,S-3 are CPL inactive with |glum| ≈ 0. This work provides a new route to control the morphology of chiral coordination polymers and improve their CPL performance.

5.
Nat Microbiol ; 9(2): 434-450, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38233647

RESUMO

A strong correlation between gut microbes and host health has been observed in numerous gut metagenomic cohort studies. However, the underlying mechanisms governing host-microbe interactions in the gut remain largely unknown. Here we report that the gut commensal Christensenella minuta modulates host metabolism by generating a previously undescribed class of secondary bile acids with 3-O-acylation substitution that inhibit the intestinal farnesoid X receptor. Administration of C. minuta alleviated features of metabolic disease in high fat diet-induced obese mice associated with a significant increase in these acylated bile acids, which we refer to as 3-O-acyl-cholic acids. Specific knockout of intestinal farnesoid X receptor in mice counteracted the beneficial effects observed in their wild-type counterparts. Finally, we showed that 3-O-acyl-CAs were prevalent in healthy humans but significantly depleted in patients with type 2 diabetes. Our findings indicate a role for C. minuta and acylated bile acids in metabolic diseases.


Assuntos
Ácidos e Sais Biliares , Diabetes Mellitus Tipo 2 , Humanos , Animais , Camundongos , Clostridiales , Dieta Hiperlipídica
6.
Inorg Chem ; 62(51): 21044-21052, 2023 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-38051505

RESUMO

Lanthanide-based molecular materials showing efficient circularly polarized luminescence (CPL) activity with a high quantum yield are attractive due to their potential applications in data storage, optical sensors, and 3D displays. Herein we present an innovative method to achieve enhanced CPL activity and a high quantum yield by doping a chromophore ligand into a coordination polymer superhelix. A series of homochiral europium(III) phosphonates with a helical morphology were prepared with the molecular formula S-, R-[Eu(cyampH)3-3n(nempH)3n]·3H2O (S/R-Eu-n, n = 0-5%). The doping of chromophore ligand S- or R-nempH2 into superhelices of S/R-Eu-0% not only turned on the CPL activity with the dissymmetry factor |glum| on the order of 10-3 but also increased the quantum yield by about 14-fold. This work may shed light on the development of efficient CPL-active lanthanide-based coordination polymers for applications.

7.
ACS Omega ; 8(50): 48432-48443, 2023 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-38144057

RESUMO

Nano-hydroxyapatite (nano-HAP) is often used as a crystal nest to induce calcium oxalate (CaOx) kidney stone formation, but the mechanism of interaction between HAP crystals of different properties and renal tubular epithelial cells remains unclear. In this study, the adhesion and endocytosis of HAP crystals with sizes of 40 nm, 70 nm, 1 µm, and 2 µm (HAP-40 nm, HAP-70 nm, HAP-1 µm, and HAP-2 µm, respectively) to human renal proximal tubular epithelial cells (HK-2) were comparatively studied. The results showed that HAP crystals of all sizes promoted the expression of osteopontin and hyaluronic acid on the cell surface, destroyed the integrity of the lysosomes, and induced the apoptosis and necrosis of cells. Nano-HAP crystals had a higher specific surface area, a smaller contact angle, a higher surface energy, and a lower Zeta potential than those of micro-HAP. Therefore, the abilities of HK-2 cells to adhere to and endocytose nano-HAP crystals were greater than their abilities to do the same for micro-HAP crystals. The order of the endocytosed crystals was as follows: HAP-40 nm > HAP-70 nm > HAP-1 µm > HAP-2 µm. The endocytosed HAP crystals entered the lysosomes. The more crystal endocytosis and adhesion there is, the more toxic it is to HK-2 cells. The results of this study showed that nanosized HAP crystals greatly promoted the formation of kidney stones than micrometer-sized HAP crystals.

8.
Case Rep Oncol ; 16(1): 1172-1182, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37900850

RESUMO

Mixed neuroendocrine non-neuroendocrine neoplasm (MiNEN) is a rare type of gastric carcinoma with controversial diagnosis and treatment. Recent data implies that deficiency mismatch repair proteins inducing microsatellite instability are considered one of the potential drivers of this disease. Hence, we report a stomach MiNEN with MMR protein loss. An admitted 60-year-old woman complained of epigastric pain. The pathological analysis of the gastro-endoscopic biopsy specimen revealed gastric adenocarcinoma. The radiological staging was cT3N1M0; therefore, she received D2 distal gastrectomy. Suspecting neuroendocrine component admix with adenocarcinoma part on the resected specimen microscopy, applying biomarkers including AE 1/3, synaptophysin, and chromogranin A to confirm the diagnosis of MiNEN. The neuroendocrine part was classified as neuroendocrine tumor grade 2 with Ki 67 at 16.5%. To further understand the molecular characterization of this disease, we evaluated mismatch protein expression by staining MLH1, MSH2, MSH6, and PMS2 antibodies. Interestingly, both components lost MLH1 and PMS2 proteins. Her radical surgery followed oxaliplatin/capecitabine adjuvant chemotherapy. The patient is still well after eight cycles of chemotherapy. dMMR gastric MiNENs and dMMR gastric cancer share many clinical and genetic characteristics. Further studies are necessary to survey the role of dMMR in the prognosis and treatment of this entity.

9.
J Am Chem Soc ; 145(44): 23948-23962, 2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-37886816

RESUMO

Assembling macroscopic helices with controllable chirality and understanding their formation mechanism are highly desirable but challenging tasks for artificial systems, especially coordination polymers. Here, we utilize solvents as an effective tool to induce the formation of macroscopic helices of chiral coordination polymers (CPs) and manipulate their helical sense. We chose the Ni/R-,S-BrpempH2 system with a one-dimensional tubular structure, where R-,S-BrpempH2 stands for R-,S-(1-(4-bromophenyl)ethylaminomethylphosphonic acid). The morphology of the self-assemblies can be controlled by varying the cosolvent in water, resulting in the formation of twisted ribbons of R-,S-Ni(Brpemp)(H2O)·H2O (R-,S-2T) in pure H2O; needle-like crystals of R-,S-Ni(Brpemp)(H2O)2·1/3CH3CN (R-,S-1C) in 20 vol % CH3CN/H2O; nanofibers of R-,S-Ni(Brpemp)(H2O)·H2O (R-,S-3F) in 20-40 vol % methanol/H2O or ethanol/H2O; and superhelices of R-,S-Ni(Brpemp)(H2O)·H2O (R-,S-4H or 5H) in 40 vol % propanol/H2O. Interestingly, the helicity of the superhelix can be controlled by using a propanol isomer in water. For the Ni/R-BrpempH2 system, a left-handed superhelix of R-4H(M) was obtained in 40 vol % NPA/H2O, while a right-handed superhelix of R-5H(P) was isolated in 40 vol % IPA/H2O. These results were rationalized by theoretical calculations. Adsorption studies revealed the chiral recognition behavior of these compounds. This work may contribute to the development of chiral CPs with a macroscopic helical morphology and interesting functionalities.

10.
Diagnostics (Basel) ; 13(17)2023 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-37685305

RESUMO

Background: Extranodal non-Hodgkin lymphoma (NHL) is more prevalent in the gastrointestinal (GI) tract than in other sites. This study aimed to determine the endoscopic characteristics of primary gastrointestinal non-Hodgkin lymphomas. Methods: We investigated 140 patients from three tertiary referral hospitals with primary malignant lymphoma of the gastrointestinal tract. Characteristics of the lesions were evaluated and analyzed using image-enhanced endoscopy, endoscopic ultrasound, and histopathology. Results: The median age was 60.5 (range: 11-99), and 59 (42.1%) were female. The most frequent complaint was abdominal pain (74.3%), followed by bloody feces (10%) and diarrhea (2.9%). B symptoms were observed in 15 (10.7%) patients. GI obstruction was the most common complication (10.0%), followed by hemorrhage (7.9%) and perforation (1.5%). Regarding endoscopic findings, the identified sites were the following: the stomach (61.4%), colon (10%), small intestine (10%), ileocecum (8.6%), rectum (6.4%), and duodenum (3.6%). Diffuse large B-cell lymphoma (DLBCL) and mucosa-associated lymphoid tissue (MALT) lymphoma are most prevalent in the stomach. Helicobacter pylori was identified in 46 cases (39.0%), with MALT lymphoma being the most infected subtype. Nearly all gastrointestinal non-Hodgkin lymphomas manifested as superficial type (25-59.6%) and ulcer type (15.6-50%) under endoscopy. We found that fungating type and protruding with ulcer type were more frequent types of aggressive lymphomas (diffuse large B-cell lymphoma, mantle cell lymphoma, and T-cell lymphoma) compared to the indolent types (MALT lymphoma, follicular lymphoma, duodenal-type follicular lymphoma, and small lymphocytic lymphoma) (p < 0.05). Conclusions: This study showed that most subtypes of gastrointestinal non-Hodgkin lymphomas exhibited same endoscopic features (superficial type and ulcer type). Aggressive gastrointestinal non-Hodgkin lymphomas (diffuse large B-cell lymphoma, mantle cell lymphoma, and T-cell lymphoma) were highly suspected when fungating lesions and protruding with ulcer lesions were encountered under endoscopy. Endoscopists should be aware of the connection between enhanced endoscopic characteristics and histological varieties of gastrointestinal lymphoma to improve diagnosis.

11.
Nat Commun ; 14(1): 6093, 2023 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-37773159

RESUMO

Magnon polarons are novel elementary excitations possessing hybrid magnonic and phononic signatures, and are responsible for many exotic spintronic and magnonic phenomena. Despite long-term sustained experimental efforts in chasing for magnon polarons, direct spectroscopic evidence of their existence is hardly observed. Here, we report the direct observation of magnon polarons using neutron spectroscopy on a multiferroic Fe2Mo3O8 possessing strong magnon-phonon coupling. Specifically, below the magnetic ordering temperature, a gap opens at the nominal intersection of the original magnon and phonon bands, leading to two separated magnon-polaron bands. Each of the bands undergoes mixing, interconverting and reversing between its magnonic and phononic components. We attribute the formation of magnon polarons to the strong magnon-phonon coupling induced by Dzyaloshinskii-Moriya interaction. Intriguingly, we find that the band-inverted magnon polarons are topologically nontrivial. These results uncover exotic elementary excitations arising from the magnon-phonon coupling, and offer a new route to topological states by considering hybridizations between different types of fundamental excitations.

12.
Dalton Trans ; 52(34): 11913-11921, 2023 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-37563974

RESUMO

Polymorphic layered lanthanide coordination polymers provide opportunities to study the effect of intralayer and interlayer interactions on their magnetic dynamics. Herein we report a series of layered lanthanide phosphonates, namely, α-Ln(2-qpH)(SO4)(H2O)2 (Ln = Sm) (α-Ln), ß-Ln(2-qpH)(SO4)(H2O)2 (Ln = Pr, Nd, Sm) (ß-Ln) and γ-Ln(2-qpH)(SO4)(H2O)2 (Ln = La, Ce, Pr, Nd, Sm) (γ-Ln) (2-qpH2 = 2-quinolinephosphonic acid), which crystallize in monoclinic P21/c (α-Ln), triclinic P1̄ (ß-Ln) and orthorhombic Pbca (γ-Ln) space groups, respectively. The structural differences between the ß- and γ-phases lie not only in the intralayer but also in the interlayer. Within the layers, the Ln2O2 dimers are aligned parallel in the ß-phase, but are non-parallel in the γ-phase. In the interlayer, there are π-π interactions between the quinoline groups in the α- and ß-phases but not in the γ-phase. Magnetic studies reveal a field-induced slow relaxation of the magnetisation at low temperatures for compounds γ-Ce, ß-Nd, and γ-Nd, and the impact of polymorphism on the magnetic dynamics of Nd(III) compounds is discussed.

13.
Dalton Trans ; 52(30): 10489-10498, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37440177

RESUMO

Lanthanide clusters with good stability and intriguing physical properties are attractive in many fields. By reacting 9-anthracenylphosphonic acid (AnPO3H2) and lanthanide nitrates under solvothermal conditions, we obtained a series of hexanuclear lanthanide phosphonate cages [H3O][Ln6(PO4)(AnPO3)8(DMF)6]·2DMF·H2O (Ln6, Ln = NdIII, EuIII, GdIII, DyIII, HoIII, ErIII, YbIII). Within the cluster, the six Ln atoms form an octahedron and its eight faces are covered by phosphonate groups. The in situ generated phosphate anion resides inside the cage and binds to the six Ln atoms via its four oxygen atoms. Photoluminescence studies show that Nd6, Er6 and Yb6 can emit near-infrared (NIR) luminescence due to the energy transfer from the anthracene ligand to the lanthanide ions. Magnetic studies reveal the magnetocaloric effect of Gd6 with an entropy change (-ΔSm) of 25.92 J kg-1 K-1 at 2.5 K and ΔH = 0-7 T. The possibility of using Gd6 as a contrast agent for magnetic resonance imaging was also explored with longitudinal (r1) and transverse (r2) relaxivities of 5.68 mM-1 s-1 per Gd and 158.11 mM-1 s-1 per Gd, respectively.

14.
Adv Mater ; 35(36): e2302568, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37285053

RESUMO

Fe3 GeTe2 have proven to be of greatly intrigue. However, the underlying mechanism behind the varying Curie temperature (Tc ) values remains a puzzle. This study explores the atomic structure of Fe3 GeTe2 crystals exhibiting Tc values of 160, 210, and 230 K. The elemental mapping reveals a Fe-intercalation on the interstitial sites within the van der Waals gap of the high-Tc (210 and 230 K) samples, which are observed to have an exchange bias effect by electrical transport measurements, while Fe intercalation or the bias effect is absent in the low-Tc (160 K) samples. First-principles calculations further suggest that the Fe-intercalation layer may be responsible for the local antiferromagnetic coupling that gives rise to the exchange bias effect, and that the interlayer exchange paths greatly contribute to the enhancement of Tc . This discovery of the Fe-intercalation layer elucidates the mechanism behind the hidden antiferromagnetic ordering that underlies the enhancement of Tc in Fe3 GeTe2 .

15.
Bioengineering (Basel) ; 10(6)2023 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-37370592

RESUMO

OBJECTIVES: Platelet-rich fibrin (PRF) and bone marrow mononuclear cells are potential scaffolds and cell sources for osteochondral regeneration. The main aim of this paper is to examine the effects of PRF scaffolds and autologous uncultured bone marrow mononuclear cells on osteochondral regeneration in rabbit knees. MATERIALS AND METHODS: Three different types of PRF scaffolds were generated from peripheral blood (Ch-PRF and L-PRF) and bone marrow combined with uncultured bone marrow mononuclear cells (BMM-PRF). The histological characteristics of these scaffolds were assessed via hematoxylin-eosin staining, PicroSirius red staining, and immunohistochemical staining. Osteochondral defects with a diameter of 3 mm and depth of 3 mm were created on the trochlear groove of the rabbit's femur. Different PRF scaffolds were then applied to treat the defects. A group of rabbits with induced osteochondral defects that were not treated with any scaffold was used as a control. Osteochondral tissue regeneration was assessed after 2, 4, and 6 weeks by macroscopy (using the Internal Cartilage Repair Society score, X-ray) and microscopy (hematoxylin-eosin stain, safranin O stain, toluidine stain, and Wakitani histological scale, immunohistochemistry), in addition to gene expression analysis of osteochondral markers. RESULTS: Ch-PRF had a heterogeneous fibrin network structure and cellular population; L-PRF and BMM-PRF had a homogeneous structure with a uniform distribution of the fibrin network. Ch-PRF and L-PRF contained a population of CD45-positive leukocytes embedded in the fibrin network, while mononuclear cells in the BMM-PRF scaffold were positive for the pluripotent stem cell-specific antibody Oct-4. In comparison to the untreated group, the rabbits that were given the autologous graft displayed significantly improved healing of the articular cartilage tissue and of the subchondral bone. Regeneration was gradually observed after 2, 4, and 6 weeks of PRF scaffold treatment, which was particularly evident in the BMM-PRF group. CONCLUSIONS: The combination of biomaterials with autologous platelet-rich fibrin and uncultured bone marrow mononuclear cells promoted osteochondral regeneration in a rabbit model more than platelet-rich fibrin material alone. Our results indicate that autologous platelet-rich fibrin scaffolds combined with uncultured bone marrow mononuclear cells applied in healing osteochondral lesions may represent a suitable treatment in addition to stem cell and biomaterial therapy.

16.
BMC Vet Res ; 19(1): 46, 2023 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-36765329

RESUMO

BACKGROUND: Porcine epidemic diarrhea (PED), caused by PED virus (PEDV), is a severe enteric disease burdening the global swine industry in recent years. Especially, the mortality of PED in neonatal piglets approaches 100%. Maternal antibodies in milk, particularly immunoglobulin A (IgA) antibodies, are of great importance for protection neonatal suckling piglets against PEDV infection as passive lactogenic immunity. Therefore, appropriate detection methods are required for detecting PEDV IgA antibodies in milk. In the current study, we prepared monoclonal antibodies (mAbs) against PEDV spike (S) glycoprotein. An enzyme-linked immunosorbent assay (ELISA) was subsequently developed based on PEDV antigen capture by a specific anti-S mAb. RESULTS: The developed ELISA showed high sensitivity (the maximum dilution of milk samples up to 1:1280) and repeatability (coefficient of variation values < 10%) in detecting PEDV IgA antibody positive and negative milk samples. More importantly, the developed ELISA showed a high coincidence rate with a commercial ELISA kit for PEDV IgA antibody detection in clinical milk samples. CONCLUSIONS: The developed ELISA in the current study is applicable for PEDV IgA antibody detection in milk samples, which is beneficial for evaluating vaccination efficacies and neonate immune status against the virus.


Assuntos
Infecções por Coronavirus , Vírus da Diarreia Epidêmica Suína , Doenças dos Suínos , Animais , Suínos , Leite , Anticorpos Antivirais , Antígenos Virais , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/veterinária , Infecções por Coronavirus/prevenção & controle , Ensaio de Imunoadsorção Enzimática/veterinária , Ensaio de Imunoadsorção Enzimática/métodos , Anticorpos Monoclonais , Imunoglobulina A
17.
Chemistry ; 29(12): e202203454, 2023 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-36445817

RESUMO

Photosensitive lanthanide-based single-molecule magnets (Ln-SMM) are very attractive for their potential applications in information storage, switching, and sensors. However, the light-driven structural transformation in Ln-SMMs hardly changes the coordination number of the lanthanide ion. Herein, for the first time it is reported that X-ray (λ=0.71073 Å) irradiation can break the coordination bond of Dy-OH2 in the three-dimensional (3D) metal-organic framework Dy2 (amp2 H2 )3 (H2 O)6 ⋅ 4H2 O (MDAF-5), in which the {Dy2 (OPO)2 } dimers are cross-linked by dianthracene-phosphonate ligands. The structural transformation proceeds in a single-crystal-to-single-crystal (SC-SC) fashion, forming the new phase Dy2 (amp2 H2 )3 (H2 O)4 ⋅ 4H2 O (MDAF-5-X). The phase transition is accompanied by a significant change in magnetic properties due to the alteration in coordination geometry of the DyIII ion from a distorted pentagonal bipyramid in MDAF-5 to a distorted octahedron in MDAF-5-X.

18.
Nano Lett ; 22(24): 10018-10024, 2022 12 28.
Artigo em Inglês | MEDLINE | ID: mdl-36475866

RESUMO

Reversible regulation of ferroelectric polarization possesses great potentials recently in bionic neural networks. Photoinduced cis-trans isomers have changeable dipole moments, but they cannot be directed to some specific orientation. Here, we construct a host-guest composite structure which consists of a porous ferroelectric metal (Ni)-organic framework [Ni(DPA)2] as host and photoisomer, azobenzene (AZB), as guest molecules. When AZB molecules are embedded in the nanopores of Ni(DPA)2 in the form of a single molecule, polarization strength tunable regulation is realized after ultraviolet irradiation of 365 and 405 nm via cis-trans isomerism transformation of AZB. An intrinsic built-in field originating from the distorted {NiN2O4} octahedra in Ni(DPA)2 directs the dipole moments of AZB to the applied electric field. As a result, the overlapped ferroelectric polarization strength changes with content of cis-AZB after ultraviolet and visible irradiation. Such a connection of ferroelectric Ni(DPA)2 structure with cis-trans isomers provides an important strategy for regulating the ferroelectric polarization strength.


Assuntos
Estruturas Metalorgânicas , Isomerismo , Luz , Raios Ultravioleta
19.
Front Genet ; 13: 1019687, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36457752

RESUMO

Meat quality, an important economic trait, is regulated by many factors, especially by genetic factors, including coding genes, miRNAs, and lncRNAs. Recent studies have elucidated that circRNAs also play a key role in muscle development and lipid deposition. However, the functions and regulatory mechanisms of circRNAs in meat quality remain mostly unknown. The circRNA expression profiles between Huainan pigs (Chinese indigenous pigs, fat-type, Huainan HN) and Large White pigs (Western commercial pigs, lean-type, LW) in the longissimus dorsi (LD) muscle at 38, 58, and 78 days post conception (dpc) were compared by sequencing. In total, 39,887 circRNAs were identified in 18 samples, and 60, 78, and 86 differentially expressed circRNAs (DECs) were found at the three stages mentioned above between these two breeds. The parent genes of DECs were enriched in myogenesis, proliferation, adipogenesis and muscle fiber-type transition. The circRNA-miRNA interaction networks included 38 DECs and 47 miRNAs, and these miRNAs were involved in muscle development and lipid metabolism. Two shared DECs (circ_0030593 and circ_0032760) of these three stages were selected, their head-to-tail junction sites were validated by Sanger sequencing, and RT‒qPCR results suggested that these two DECs might be involved in intramuscular fat deposition. These findings provide a basis for understanding the role of circRNAs in meat quality.

20.
Chem Commun (Camb) ; 58(60): 8372-8375, 2022 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-35792066

RESUMO

A highly stable and porous MOF [Zr2(H4TPPP)(OH/F)2]·xH2O (1) containing a metal-free porphyrin-phosphonate ligand is reported. It shows high proton conductivity of 1.2 × 10-3 S·cm-1 at 25 °C and 95% RH, a photothermal effect over a wide spectral range from UV-vis to NIR, and photo-enhanced and switchable proton conductivity.

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