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1.
Mol Cell ; 75(4): 823-834.e5, 2019 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-31302001

RESUMO

Sirt3, as a major mitochondrial nicotinamide adenine dinucleotide (NAD)-dependent deacetylase, is required for mitochondrial metabolic adaption to various stresses. However, how to regulate Sirt3 activity responding to metabolic stress remains largely unknown. Here, we report Sirt3 as a SUMOylated protein in mitochondria. SUMOylation suppresses Sirt3 catalytic activity. SUMOylation-deficient Sirt3 shows elevated deacetylation on mitochondrial proteins and increased fatty acid oxidation. During fasting, SUMO-specific protease SENP1 is accumulated in mitochondria and quickly de-SUMOylates and activates Sirt3. SENP1 deficiency results in hyper-SUMOylation of Sirt3 and hyper-acetylation of mitochondrial proteins, which reduces mitochondrial metabolic adaption responding to fasting. Furthermore, we find that fasting induces SENP1 translocation into mitochondria to activate Sirt3. The studies on mice show that Sirt3 SUMOylation mutation reduces fat mass and antagonizes high-fat diet (HFD)-induced obesity via increasing oxidative phosphorylation and energy expenditure. Our results reveal that SENP1-Sirt3 signaling modulates Sirt3 activation and mitochondrial metabolism during metabolic stress.


Assuntos
Cisteína Endopeptidases/metabolismo , Mitocôndrias/metabolismo , Mutação , Obesidade/metabolismo , Transdução de Sinais , Sirtuína 3/metabolismo , Sumoilação , Acetilação , Animais , Cisteína Endopeptidases/genética , Gorduras na Dieta/efeitos adversos , Gorduras na Dieta/farmacologia , Células HEK293 , Humanos , Masculino , Camundongos , Camundongos Mutantes , Mitocôndrias/genética , Mitocôndrias/patologia , Obesidade/induzido quimicamente , Obesidade/genética , Obesidade/patologia , Sirtuína 3/genética
2.
J Mol Cell Cardiol ; 193: 36-52, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38795767

RESUMO

BACKGROUND: Atherosclerosis is a chronic pathology, leading to acute coronary heart disease or stroke. MiR-127 has been found significantly upregulated in advanced atherosclerosis. But its function in atherosclerosis remains unexplored. We explored the role of miR-127-3p in regulating atherosclerosis development and its downstream mechanisms. METHODS: The expression profile of miR-127 in carotid atherosclerotic plaques of 23 patients with severe carotid stenosis was detected by RT-qPCR and in situ hybridization. Primary bone marrow-derived macrophages (BMDM) stimulated with oxidized low-density lipoprotein were used as an in vitro model. CCK-8, EdU, RT-qPCR, and flow cytometry were used to detect the proliferative capacity and polarization of BMDM, which were infected by lentivirus-carrying plasmid to upregulate or downregulate miR-127-3p expression, respectively. RNA sequencing combined with bioinformatic analysis and targeted fatty acid metabolomics approach were used to detect the transcriptome and lipid metabolites. The association between miR-127-3p and its target was verified by dual-luciferase activity reporting and Western blotting. Oxygen consumption rate of BMDM were detected using seahorse analysis. High-cholesterol-diet-fed low density lipoprotein deficient (LDLR-/-) mice, with-or-without carotid tandem-stenosis surgery, were treated with miR-127-3p agomir or antagomir to examine its effect on plaque development and stability. RESULTS: miR-127-3p, not -5p, is elevated in human advanced carotid atheroma and its expression is positively associated with macrophage accummulation in plaques. In vitro, miR-127-3p-overexpressed macrophage exhibites increased proliferation capacity and facilitates M1 polariztion whereas the contrary trend is present in miR-127-3p-inhibited macrophage. Stearoyl-CoA desaturase-1 (SCD1) is one potential target of miR-127-3p. miR-127-3p mimics decreases the activity of 3' untranslated regions of SCD-1. Furthermore, miR-127-3p downregulates SCD1 expression, and reversing the expression of SCD1 attenuates the increased proliferation induced by miR-127-3p overexpression in macrophage. miR-127-3p overexpression could also lead to decreased content of unsaturated fatty acids (UFAs), increased content of acetyl CoA and increased level of oxidative phosphorylation. In vivo, miR-127-3p agomir significantly increases atherosclerosis progression, macrophage proliferation and decreases SCD1 expression and the content of UFAs in aortic plaques of LDLR-/- mice. Conversely, miR-127-3p antagomir attenuated atherosclerosis, macrophage proliferation in LDLR-/- mice, and enhanced carotid plaque stability in mice with vulnerable plaque induced. CONCLUSION: MiR-127-3p enhances proliferation in macrophages through downregulating SCD-1 expression and decreasing the content of unsaturated fatty acid, thereby promoting atherosclerosis development and decreasing plaque stability. miR-127-3p/SCD1/UFAs might provide potential therapeutic target for anti-inflammation and atherosclerosis.

3.
Small ; 20(3): e2306459, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37679055

RESUMO

Nonlinear optical (NLO) crystals are indispensable for the solid-state lasers for their ability to expand wavelength spectral to the regions where the directing lasing is difficult or even impossible, yet the rational design of a high-performance NLO crystal remains a great challenge owing to the severe structural and properties' requirements. Herein, a new noncentrosymmetric (NCS) and polar gallium iodate, LiGa(IO3 )4 , with a novel 2D anionic layer, is successfully designed and synthesized by the aliovalent substitution strategy based on classic α-LiIO3 . The 2D [Ga(IO3 )4 ]∞ - layer in LiGa(IO3 )4 is built from the GaO6 octahedra and highly polarizable units IO3 . Compared with its parent compound, the partial replacement of A-site Li+ cation with main group Ga3+ cation facilitates LiGa(IO3 )4 to possess excellent NLO properties, including the large second-harmonic generation (SHG) response (14 × KH2 PO4 (KDP) @ 1064 nm), wide bandgap (4.25 eV), large birefringence (0.23 @ 1064 nm), and wide optical transparency from UV to mid-IR. These reveal that LiGa(IO3 )4 will be a promising NLO crystal.

4.
Small ; 20(10): e2305659, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37884477

RESUMO

Spinal cord injury (SCI) is a severe neurological disorder characterized by significant disability and limited treatment options. Mitigating the secondary inflammatory response following the initial injury is the primary focus of current research in the treatment of SCI. CCL2 (C─C motif chemokine ligand 2) serves as the primary regulator responsible for inflammatory chemotaxis of the majority of peripheral immune cells, blocking the CCL2-CCR2 (C─C chemokine receptor type 2) axis has shown considerable therapeutic potential for inflammatory diseases, including SCI. In this study, it presents a multifunctional biomimetic nanoplatform (CCR2-MM@PLGA/Cur) specifically designed to target the CCL2-CCR2 axis, which consisted of an engineered macrophage membrane (MM) coating with enhanced CCR2 expression and a PLGA (poly (lactic-co-glycolic acid)) nanoparticle that encapsulated therapeutic drugs. CCR2 overexpression on MM not only enhanced drug-targeted delivery to the injury site, but also attenuated macrophage infiltration, microglia pro-inflammatory polarization, and neuronal apoptosis by trapping CCL2. Consequently, it facilitated neural regeneration and motor function recovery in SCI mice, enabling a comprehensive treatment approach for SCI. The feasibility and efficacy of this platform are confirmed through a series of in vitro and in vivo assays, offering new insights and potential avenues for further exploration in the treatment of SCI.


Assuntos
Nanopartículas , Traumatismos da Medula Espinal , Camundongos , Animais , Quimiocina CCL2/metabolismo , Doenças Neuroinflamatórias , Macrófagos/metabolismo , Traumatismos da Medula Espinal/terapia
5.
Opt Express ; 32(11): 20316-20325, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38859145

RESUMO

Yellow lasers at 590 nm have many extensive applications in our daily life, but extremely difficult to attain by traditional solid-state laser technology, owing to the absence of highly-efficient transition channels at this spectral range. In this work, we proposed a cooperative lasing mechanism to obtain the yellow light emission, with multiphonon-assisted electronic transitions and phase-matched frequency-doubling. Based on the predictable configurational coordinate model, we can calculate the multiphonon-assisted emission step-by-step. Using Yb3+-doped La2CaB10O19 crystal as an example, it is capable of producing yellow laser at 581-590 nm, with a maximum output power of 4.83 W and a high slope efficiency of 31.6%. To the best of our knowledge, it represents the highest power of solid-state yellow laser realized in one single crystal pumped by a laser diode. This power scaling can be assigned to the amplified phonon-assisted emission beyond the fluorescence spectrum, and optimized crystal angle for phase-matching condition. Such a compact, low-cost, and high-power laser device, provides an alternative candidate for the spectral "yellow-gap" where no practical solid-state laser exists at present.

6.
Acta Psychiatr Scand ; 150(1): 5-21, 2024 07.
Artigo em Inglês | MEDLINE | ID: mdl-38616056

RESUMO

INTRODUCTION: Despite its high lifetime prevalence rate and the elevated disability caused by posttraumatic stress disorder (PTSD), treatments exhibit modest efficacy. In consideration of the abnormal connectivity between the dorsolateral prefrontal cortex (DLPFC) and amygdala in PTSD, several randomized controlled trials (RCTs) addressing the efficacy of different noninvasive brain stimulation (NIBS) modalities for PTSD management have been undertaken. However, previous RCTs have reported inconsistent results. The current network meta-analysis (NMA) aimed to compare the efficacy and acceptability of various NIBS protocols in PTSD management. METHODS: We systematically searched ClinicalKey, Cochrane Central Register of Controlled Trials, Embase, ProQuest, PubMed, ScienceDirect, Web of Science, and ClinicalTrials.gov to identify relevant RCTs. The targeted RCTs was those comparing the efficacy of NIBS interventions, such as transcranial direct current stimulation (tDCS), repetitive transcranial magnetic stimulation (rTMS), and transcutaneous cervical vagal nerve stimulation, in patients with PTSD. The NMA was conducted using a frequentist model. The primary outcomes were changes in the overall severity of PTSD and acceptability (to be specific, rates of dropouts for any reason). RESULTS: We identified 14 RCTs that enrolled 686 participants. The NMA demonstrated that among the investigated NIBS types, high-frequency rTMS over bilateral DLPFCs was associated with the greatest reduction in overall PTSD severity. Further, in comparison with the sham controls, excitatory stimulation over the right DLPFC with/without excitatory stimulation over left DLPFC were associated with significant reductions in PTSD-related symptoms, including depression and anxiety symptoms, and overall PTSD severity. CONCLUSIONS: This NMA demonstrated that excitatory stimulation over the right DLPFC with or without excitatory stimulation over left DLPFC were associated with significant reductions in PTSD-related symptoms. TRIAL REGISTRATION: PROSPERO CRD42023391562.


Assuntos
Metanálise em Rede , Ensaios Clínicos Controlados Aleatórios como Assunto , Transtornos de Estresse Pós-Traumáticos , Estimulação Transcraniana por Corrente Contínua , Estimulação Magnética Transcraniana , Humanos , Aceitação pelo Paciente de Cuidados de Saúde , Transtornos de Estresse Pós-Traumáticos/terapia , Estimulação Transcraniana por Corrente Contínua/métodos , Estimulação Magnética Transcraniana/métodos , Resultado do Tratamento , Estimulação do Nervo Vago/métodos
7.
Inorg Chem ; 63(5): 2844-2850, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38262613

RESUMO

Borate materials are of significant interest due to their versatile structural configuration and competitive ultraviolet (UV) transparency range. In this study, we present a novel rare-earth borate crystal, KNa2Lu(BO3)2, synthesized for the first time through a facile spontaneous crystallization method. It adopts the centrosymmetric space group Pnma (no. 62) and yields a unique three-dimensional (3D) structural network formed by isolated [BO3] plane triangles and distorted [LuO7] polyhedra. This compound displays excellent thermal stability up to ∼990 °C, demonstrating a favorable congruent melting nature. Moreover, KNa2Lu(BO3)2 achieves a notably short UV absorption cutoff at approximately 204 nm, yielding a large band gap of 5.58 eV. Remarkably, it showcases an enlarged birefringence of 0.044 at 1064 nm, implying its potential as a birefringent material. Moreover, density functional theory calculations demonstrate that the optical characteristics are predominantly influenced by fundamental building blocks [BO3] triangles and distorted [LuO7] polyhedra. Our findings demonstrate the potential of KNa2Lu(BO3)2 in the development of a birefringent candidate and enrich the structural chemistry of rare-earth-based borates.

8.
Inorg Chem ; 63(2): 1404-1413, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38163854

RESUMO

Introducing F- anions or substituting F- anions with IO3- groups has been proven to be ideal strategies for designing novel noncentrosymmetric (NCS) and polar materials, yet systematic investigation into the effect of F- anions or the substitution of IO3- for F- anions on structures and properties remains rarely explored. Herein, two new gallium iodates, NaGa(IO3)2F2 (1) and NaGa(IO3)4 (2), were successfully designed and synthesized based on NaGa(IO3)3F by introducing more F- anions and replacing F- anions with IO3 groups, respectively. Structurally, in compound 1, the adjacent [GaF3(IO3)3]3- polyanions are connected in an antiparallel manner, resulting in a complete cancellation of local polarity. While in compound 2, all IO3 groups in 2D [Ga(IO3)4]∞- layers are aligned, leading to large macroscopic polarization. Additionally, chemical substitution also results in a qualitative improvement in the functional properties of compound 2. It possesses strong SHG response (12 × KDP @1064 nm) and broad optical transparency, coupled with large birefringence (0.21 @1064 nm), showcasing its promise as a promising nonlinear optical (NLO) crystal. The effects of chemical substitution between F- anions and IO3- groups on the structures and properties are discussed in detail.

9.
Inorg Chem ; 63(11): 4807-4812, 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38446174

RESUMO

Two new congruently melting Pb-containing halogen silicates, Pb3[O10Pb20](SiO4)4X10 (X = Cl, Br), have been synthesized using a high-temperature solution method. Their crystal structures were determined by single-crystal X-ray diffraction, and both compounds crystallize in the orthorhombic space group Cmca. In both structures, the mirror-symmetric bilayer composed of Pb-O polyhedra is observed for the first time in Pb-containing silicates and belongs to α-PbO derivatives and is related to the Aurivillius phase. Thermal behavior analysis, UV-vis diffuse-reflectance spectroscopy, and IR spectroscopy were also performed. The Pb3[O10Pb20](SiO4)4Cl10 matrix was doped with Eu3+ ions as a dopant, and its potential application in fluorescence was confirmed from the resulting orange-red emission.

10.
Inorg Chem ; 63(8): 3986-3991, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38359456

RESUMO

Germanate is garnering increasing attention in the field of optoelectronics owing to its competitive optical transparency and robust stability. Herein, a novel lithium-rich rare-earth germanate, Li13YGe4O16, was fabricated for the first time using a high-temperature solution approach. This compound adopts the asymmetric space group Cmc21 (no. 36), characterized by isolated [YO6] and [GeO4] structural motifs with Li+ cations located in the channel. Notably, Li13YGe4O16 presents a short ultraviolet cutoff edge at 240 nm, indicative of an enlarged band gap of 4.96 eV and showcases a wide mid-infrared transmission region exceeding 6.0 µm. Moreover, Li13YGe4O16 features exceptional thermal stability and moderate second harmonic generation (SHG) intensity. Additionally, a theoretical analysis suggests that the distorted [YO6] octahedra. [GeO4] and [LiO4] tetrahedra play a significant role in the optical activities of Li13YGe4O16. These attributes endow Li13YGe4O16 with the potential to serve as a new mid-IR nonlinear optical (NLO) crystal and enrich the structural chemistry of germanates.

11.
Eur J Pediatr ; 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38806862

RESUMO

The prevalence of pediatric constipation ranges from 0.7 to 29.6% across different countries. Functional constipation accounts for 95% of pediatric constipation, and the efficacy of pharmacotherapy is limited, with a success rate of 60%. Several randomized controlled trials (RCTs) have shown the benefits of probiotic supplements in treating this condition. However, the reported strains of probiotics varied among the RCTs. We aimed to compare the efficacy and acceptability of different probiotic supplements for pediatric functional constipation. The current frequentist model-based network meta-analysis (NMA) included RCTs of probiotic supplements for functional constipation in children. The primary outcome was changes in bowel movement or stool frequency; acceptability outcome was all-cause discontinuation. Nine RCTs were included (N = 710; mean age = 5.5 years; 49.4% girls). Most probiotic products, used either alone or combined with laxatives, were associated with significantly better improvement in bowel movement or stool frequency than placebo/control. Protexin plus laxatives (standardized mean difference (SMD) = 1.87, 95% confidence interval (95% CI) = 0.85 to 2.90) were associated with the greatest improvement in bowel movement or stool frequency among all the investigated probiotic products. For the single probiotic interventions, only Lactobacillus casei rhamnosus Lcr35 was associated with significant efficacy compared to placebo/control treatments (SMD = 1.37, 95% CI: 0.32 to 2.43). All the investigated probiotic products had fecal incontinence and patient drop-out rates similar to those of placebo/control treatments.  Conclusion: The results of our NMA support the application of an advanced combination of probiotics and laxatives for pediatric functional constipation if there is no concurrent contraindication.  Registration: PROSPERO (CRD42022298724). What is Known: • Despite of the high prevalence of pediatric constipation, which ranges from 0.7% to 29.6%, the efficacy of pharmacotherapy is limited, with a success rate of 60%. Several randomized controlled trials (RCTs) have shown the benefits of probiotic supplements in treating this condition. However, the reported strains of probiotics varied among the RCTs. The widely heterogeneous strains of probiotics let the traditional meta-analysis, which pooled all different strains into one group, be nonsense and insignificant. What is New: • By conducting a comprehensive network meta-analysis, we aimed to compare the efficacy and acceptability of different strains of probiotic supplements for pediatric functional constipation. Network meta-analysis of nine randomized controlled trials revealed that the most probiotic products, used either alone or combined with laxatives, were associated with significantly better improvement in bowel movement or stool frequency than placebo/control. Protexin plus laxatives was associated with the greatest improvement in bowel movement or stool frequency among all the investigated probiotic products. For the single probiotic interventions, only Lactobacillus casei rhamnosus Lcr35 was associated with significant efficacy compared to placebo/control treatments. All the investigated probiotic products had fecal incontinence and patient drop-out rates similar to those of placebo/control treatments.

12.
J Environ Manage ; 359: 121009, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38718600

RESUMO

Nitrification-denitrification process has failed to meet wastewater treatment standards. The completely autotrophic nitrite removal (CANON) process has a huge advantage in the field of low carbon/nitrogen wastewater nitrogen removal. However, slow start-up and system instability limit its applications. In this study, the time of the start-up CANON process was reduced by using bio-rope as loading materials. The establishing of graded dissolved oxygen improved the stability of the CANON process and enhanced the stratification effect between functional microorganisms. Microbial community structure and the abundance of nitrogen removal functional genes are also analyzed. The results showed that the CANON process was initiated within 75 days in the complete absence of anaerobic ammonium oxidizing bacteria (AnAOB) inoculation. The ammonium and nitrogen removal efficiencies of CANON process reached to 94.45% and 80.76% respectively. The results also showed that the relative abundance of nitrogen removal bacterial in the biofilm gradually increases with the dissolved oxygen content in the solution decreases. In contrast, the relative abundance of ammonia oxidizing bacteria was positively correlated with the dissolved oxygen content in the solution. The relative abundance of g__Candidatus_Brocadia in biofilm was 15.56%, and while g__Nitrosomonas was just 0.6613%. Metagenomic analysis showed that g__Candidatus_Brocadia also contributes 66.37% to the partial-nitrification functional gene Hao (K10535). This study presented a new idea for the cooperation between partial-nitrification and anammox, which improved the nitrogen removal system stability.


Assuntos
Processos Autotróficos , Nitritos , Nitrogênio , Águas Residuárias , Nitrogênio/metabolismo , Nitritos/metabolismo , Nitrificação , Desnitrificação , Bactérias/metabolismo , Bactérias/genética , Eliminação de Resíduos Líquidos/métodos , Biofilmes , Reatores Biológicos , Compostos de Amônio/metabolismo
13.
J Anesth ; 38(2): 155-166, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37405496

RESUMO

PURPOSE: The prevalence of postoperative emergence delirium in paediatric patients (pedED) following desflurane anaesthesia is considerably high at 50-80%. Although several pharmacological prophylactic strategies have been introduced to reduce the risk of pedED, conclusive evidence about the superiority of these individual regimens is lacking. The aim of the current study was to assess the potential prophylactic effect and safety of individual pharmacotherapies in the prevention of pedED following desflurane anaesthesia. METHODS: This frequentist model network meta-analysis (NMA) of randomized controlled trials (RCTs) included peer-reviewed RCTs of either placebo-controlled or active-controlled design in paediatric patients under desflurane anaesthesia. RESULTS: Seven studies comprising 573 participants were included. Overall, the ketamine + propofol administration [odds ratio (OR) = 0.05, 95% confidence intervals (95%CIs) 0.01-0.33], dexmedetomidine alone (OR = 0.13, 95%CIs 0.05-0.31), and propofol administration (OR = 0.30, 95%CIs 0.10-0.91) were associated with a significantly lower incidence of pedED than the placebo/control groups. In addition, only gabapentin and dexmedetomidine were associated with a significantly higher improvement in the severity of emergence delirium than the placebo/control groups. Finally, the ketamine + propofol administration was associated with the lowest incidence of pedED, whereas gabapentin was associated with the lowest severity of pedED among all of the pharmacologic interventions studied. CONCLUSIONS: The current NMA showed that ketamine + propofol administration was associated with the lowest incidence of pedED among all of the pharmacologic interventions studied. Future large-scale trials to more fully elucidate the comparative benefits of different combination regimens are warranted. TRIAL REGISTRATION: PROSPERO CRD42021285200.


Assuntos
Anestésicos Inalatórios , Dexmedetomidina , Delírio do Despertar , Ketamina , Propofol , Humanos , Criança , Propofol/efeitos adversos , Delírio do Despertar/epidemiologia , Delírio do Despertar/prevenção & controle , Delírio do Despertar/tratamento farmacológico , Desflurano , Anestésicos Inalatórios/efeitos adversos , Gabapentina , Metanálise em Rede , Anestesia Geral
14.
Angew Chem Int Ed Engl ; 63(15): e202400892, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38302689

RESUMO

Non-centrosymmetric (NCS) and polar materials capable of exhibiting many important functional properties are indispensable for electro-optical technologies, yet their rational structural design remains a significant challenge. Here, we report a "group grafting" strategy for designing the first multi-chromophore selenophosphate, Cs3In(In4Se7)(P2Se6), that crystallizes in a NCS and polar space group of Cm. The structure features a unique basic building unit (BBU) [In(In4Se10)(P2Se6)], formed through "grafting [In4Se10] supertetrahedra on the root of [In(P2Se6)2] groups". Theoretical calculations confirm that this [In(In4Se10)(P2Se6)] BBU can achieve a "1+1>2" combination of properties from two chromophores, [In4Se10] supertetrahedron and ethane-like [P2Se6] dimer. That makes Cs3In(In4Se7)(P2Se6) exhibit excellent linear and nonlinear optical (NLO) properties, including a strong second harmonic generation (SHG) response (~6×AgGaS2), a large band gap (2.45 eV), broad infrared (IR) transmission (up to 19.5 µm), a significant birefringence (0.26 @1064 nm) as well as the congruently-melting property at ~700 °C. Therefore, Cs3In(In4Se7)(P2Se6) will be a promising NLO crystal, especially in the IR region, and this research also demonstrates that "group grafting" will be an effective strategy for constructing novel polar BBUs with multi-chromophore to design NCS structures and high-performance IR NLO materials.

15.
Angew Chem Int Ed Engl ; 63(30): e202406318, 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-38715104

RESUMO

Achieving the extreme balance of the key performance requirements is the crucial to breakthrough the application bottleneck for nonlinear optical (NLO) materials. Herein, by assembly of the π-conjugated [B3O6] functional species with the aid of structure-directing property of mer-isomer [YO3F3] octahedra, a new ultraviolet (UV) NLO material, Cs2YB3O6F2 with aligned arrangement of coplanar [B3O6] groups has been synthesized. The polar material exhibits the rare coexistence of the largest second harmonic generation response of 5.6×KDP, the largest birefringence of 0.091 at 532 nm, the shortest Type I phase-matching down to 200.5 nm and deep-ultraviolet transparency among reported acentric rare-earth borates with [B3O6] groups. Remarkably, benefiting from the enhanced bonding force among functional units [B3O6], a firm three-dimensional framework is constructed, which facilitates the growth of large crystals. This can be proved by a block shape crystal with dimensional of 6×5×4 mm3, indicating that it was a promising UV NLO crystal. This work provides a powerful strategy to design UV NLO materials with good performances.

16.
J Am Chem Soc ; 145(23): 12691-12700, 2023 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-37236929

RESUMO

Deep-ultraviolet nonlinear optical (DUV NLO) crystals are indispensable for solid-state lasers to produce coherent light with wavelengths shorter than 200 nm, yet their structure design still faces great challenges because two groups of conflicting properties must be satisfied simultaneously, i.e., "large second harmonic generation (SHG) response-large band gap" and "large birefringence-weak growth anisotropy". Clearly, hitherto, no crystal can perfectly satisfy these properties, including KBe2BO3F2. Herein, we design a new mixed-coordinated borophosphate Cs3[(BOP)2(B3O7)3] (CBPO) by optimizing the matching of cation and anion groups, which unprecedentedly achieves a balance for two groups of contradictions concurrently for the first time. In the structure of CBPO, it has the coplanar and π-conjugated B3O7 groups, which can make it possess a large SHG response (3 × KDP) and large birefringence (0.075@532 nm). Then, terminal O atoms of these B3O7 groups are connected by BO4 and PO4 tetrahedra, which eliminates all dangling bonds and blue shifts the UV absorption edge to the DUV region (165 nm). More importantly, owing to the judicious selection of cations, the size of cations and void of anion groups is a perfect match, which makes CBPO possess a very stable three-dimensional anion framework and thus reduces the crystal growth anisotropy. A CBPO single crystal with a size of up to 20 × 17 × 8 mm3 has been successfully grown, through which a DUV coherent light has also been achieved in Be-free DUV NLO crystals for the first time. These indicate CBPO will be the next generation of DUV NLO crystals.

17.
Small ; 19(40): e2302819, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37271892

RESUMO

Salt-inclusion chalcogenides (SICs) have been receiving widespread attention due to their large second harmonic generation (SHG) responses and wide bandgaps, however most of them suffer from small birefringence limiting their technical application. Herein, by introducing the π-conjugated (S2 )2- units in the ionic guest of salt-inclusion structure, the first disulfide-bond-containing SIC, [Ba4 (S2 )][ZnGa4 S10 ] has been synthesized. It exhibits the widest bandgap up to 3.39 eV among polychalcogenides and strong SHG response as large as that of AgGaS2 (AGS). Importantly, its birefringence reaches a max value of 0.053@1064 nm among AGS-like SICs, indicating it is a promising IR nonlinear optical (NLO) material. Theoretical calculations reveal that the π-conjugated (S2 )2- units and covalent GaS layers favor the enhanced birefringence and large SHG response. This work provides not only a new type of SIC for the first time, but also new lights on the design of IR NLO materials.

18.
Opt Express ; 31(6): 9790-9799, 2023 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-37157542

RESUMO

Coupling between electronic motions and the lattice vibrations, phonons could broaden the spectral bandwidth of the fluorescence spectroscopy by the energy transferring, which was recognized from the beginning of last century and successfully applied in many vibronic lasers. However, the laser performances under electron-phonon coupling were mainly prejudged by the experimental spectroscopy. The multiphonon participated lasing mechanism is still elusive and should be in-depth investigated. Here, a direct quantitative relationship between the laser performance and phonon participating dynamic process was derived in theory. With a transition metal doped alexandrite (Cr3+:BeAl2O4) crystal, the multiphonon coupled laser performance was manifested in experiments. Associated with the Huang-Rhys factor calculations and hypothesis, the multiphonon participated lasing mechanism with phonon numbers from 2 to 5 was discovered and identified. This work provides not only a credible model for understanding the multiphonon participated lasing, but should also boost the study of laser physics in the electron-phonon-photon coupled systems.

19.
Opt Lett ; 48(18): 4913-4916, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37707935

RESUMO

Stable and miniaturized orange lasers at 591 nm are in urgent demand for ophthalmology and dermatological treatment. However, at present, traditional dye lasers and nonlinear sum-frequency lasers are limited by their complex setup and high cost, whereas semiconductor laser diodes (LDs) emitting in the yellow-orange range suffer from low output power. Here, we propose a new, to the best of our knowledge, route to create self-frequency-doubling (SFD) orange laser with a combination of multiphonon-assisted lasing and nonlinear frequency-doubling in one crystal. Using Yb3+-doped YCa4O(BO3)3 (Yb:YCOB) crystal, we first realize a widely tunable laser beyond the fluorescence spectrum in the wavelength range of 1175-1248 nm. Then, by selecting the laser polarization and crystal angle to satisfy phase-matching conditions, we obtained a directly diode-pumped orange laser at 591.8 nm with 3.07-W output power and an optical-to-optical conversion efficiency of 13%. This work represents a new step forward for portable high-power solid-state orange lasers and provides an intriguing platform for electron-phonon coupled lasing.

20.
Brain Behav Immun ; 111: 352-364, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37150266

RESUMO

Alzheimer's dementia (AD) is a major contributor to global disability, and effective therapies to modify disease progression are currently lacking. The neuro-inflammatory theory is a potential etiology underlying this neurodegenerative disease. Previous randomized, controlled trials (RCTs) have provided inconclusive results regarding efficacy of omega-3 polyunsaturated fatty acids (PUFAs) regimens, which might provide anti-inflammatory benefits in the management of AD, in improving cognitive function among participants with AD. The objective of this frequentist-model based network meta-analysis (NMA) was to evaluate the potential advantages of omega-3 PUFAs and currently FDA-approved medications for AD on overall cognitive function in AD individuals. The primary outcomes were: (1) changes in cognitive function, and (2) acceptability, which refers to all-cause discontinuation. Additionally, secondary outcomes included quality of life, behavioral disturbances and safety/tolerability, which was assessed through the frequency of any reported adverse event. This NMA included 52 RCTs (6 with omega-3 PUFAs and 46 with FDA-approved medications) involving 21,111 participants. The results showed that long-term high-dose (1500-2000 mg/day) of eicosapentaenoic acid (EPA)-dominant omega-3 PUFAs augmented with anti-oxidants had the highest potential for cognitive improvement among all investigated treatments [standardized mean difference = 3.00, 95% confidence intervals (95 %CIs) = 1.84-4.16]. Compared to placebo, omega-3 PUFAs had similar acceptability [odds ratio (OR) = 0.46, 95 %CIs = 0.04 to 5.87] and safety profiles (OR = 1.24, 95 %CIs = 0.66 to 2.33)o. These findings support the potential neurotherapeutic effects of high dosage EPA-dominant omega-3 PUFAs for the amelioration of cognitive decline in patients with AD. Future large-scale, long-term RCTs should focus on different dosages of EPA-dominant omega-3 PUFAs regimens on improving cognitive dysfunction in patients with AD at different levels of inflammatory status and psychopathology.


Assuntos
Doença de Alzheimer , Ácidos Graxos Ômega-3 , Humanos , Ácido Eicosapentaenoico/farmacologia , Ácido Eicosapentaenoico/uso terapêutico , Doença de Alzheimer/tratamento farmacológico , Metanálise em Rede , Ácidos Graxos Ômega-3/uso terapêutico , Cognição , Anti-Inflamatórios/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto
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