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1.
Opt Express ; 32(4): 4887-4901, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38439229

RESUMO

In underwater wireless optical communication, orbital angular momentum (OAM) states suffer from turbulence distortions. This study aims to investigate the effectiveness of auto-focusing and OAM entanglement of the beams in reducing the turbulence effects. We implement the single-phase approximation and the extended Huygens-Fresnel principle to derive the detection probability of the entangled Airy beams under unstable oceanic turbulence. The results show that auto-focusing can protect the signal OAM mode and suppress modal crosstalks, while entangled OAM states can further enhance the resistance against oceanic turbulence around the focus position. The numerical analysis demonstrates that after the auto-focusing position, the beams evolve in completely opposite directions, indicating that the focal length should be modulated according to the length of a practical link to enhance received signals. These findings suggest that entangled auto-focusing vortex beams may be a desirable light source in underwater communication systems.

2.
FASEB J ; 37(12): e23306, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37934018

RESUMO

Spermatogonial stem cells (SSCs) play a crucial role in mammalian spermatogenesis and maintain the stable inheritance of the germline in livestock. However, stress and bacterial or viral infections can disrupt immune homeostasis of the testes, thereby leading to spermatogenesis destruction and infertility, which severely affects the health and productivity of mammals. This study aimed to explore the effect of ubiquitin C-terminal hydrolase L1 (UCHL1) knockdown (KD) in goat SSCs and mouse testes and investigate the potential anti-inflammatory function of UCHL1 in a poly(I:C)-induced inflammation model to maintain microenvironmental homeostasis. In vitro, the downregulation of UCHL1 (UCHL1 KD) in goat SSCs increased the expression levels of apoptosis and inflammatory factors and inhibited the self-renewal and proliferation of SSCs. In vivo, the structure of seminiferous tubules and spermatogenic cells was disrupted after UCHL1 KD, and the expression levels of apoptosis- and inflammation-related proteins were significantly upregulated. Furthermore, UCHL1 inhibited the TLR3/TBK1/IRF3 pathway to resist poly(I:C)-induced inflammation in SSCs by antagonizing HSPA8 and thus maintaining SSC autoimmune homeostasis. Most importantly, the results of this study showed that UCHL1 maintained immune homeostasis of SSCs and spermatogenesis. UCHL1 KD not only inhibited the self-renewal and proliferation of goat SSCs and spermatogenesis but was also involved in the inflammatory response of goat SSCs. Additionally, UCHL1 has an antiviral function in SSCs by antagonizing HSPA8, which provides an important basis for exploring the specific mechanisms of UCHL1 in goat spermatogenesis.


Assuntos
Cabras , Espermatogônias , Animais , Masculino , Camundongos , Homeostase , Inflamação/metabolismo , Espermatogênese/fisiologia , Espermatogônias/metabolismo , Células-Tronco , Testículo/metabolismo
3.
J Nanobiotechnology ; 22(1): 279, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38783333

RESUMO

BACKGROUND: BCMA-directed autologous chimeric antigen receptor T (CAR-T) cells have shown excellent clinical efficacy in relapsed or refractory multiple myeloma (RRMM), however, the current preparation process for autologous CAR-T cells is complicated and costly. Moreover, the upregulation of CD47 expression has been observed in multiple myeloma, and anti-CD47 antibodies have shown remarkable results in clinical trials. Therefore, we focus on the development of BCMA/CD47-directed universal CAR-T (UCAR-T) cells to improve these limitations. METHODS: In this study, we employed phage display technology to screen nanobodies against BCMA and CD47 protein, and determined the characterization of nanobodies. Furthermore, we simultaneously disrupted the endogenous TRAC and B2M genes of T cells using CRISPR/Cas9 system to generate TCR and HLA double knock-out T cells, and developed BCMA/CD47-directed UCAR-T cells and detected the antitumor activity in vitro and in vivo. RESULTS: We obtained fourteen and one specific nanobodies against BCMA and CD47 protein from the immunized VHH library, respectively. BCMA/CD47-directed UCAR-T cells exhibited superior CAR expression (89.13-98.03%), and effectively killing primary human MM cells and MM cell lines. BCMA/CD47-directed UCAR-T cells demonstrated excellent antitumor activity against MM and prolonged the survival of tumor-engrafted NCG mice in vivo. CONCLUSIONS: This work demonstrated that BCMA/CD47-directed UCAR-T cells exhibited potent antitumor activity against MM in vitro and in vivo, which provides a potential strategy for the development of a novel "off-the-shelf" cellular immunotherapies for the treatment of multiple myeloma.


Assuntos
Antígeno de Maturação de Linfócitos B , Antígeno CD47 , Imunoterapia Adotiva , Mieloma Múltiplo , Receptores de Antígenos Quiméricos , Mieloma Múltiplo/terapia , Mieloma Múltiplo/imunologia , Humanos , Animais , Antígeno CD47/imunologia , Antígeno de Maturação de Linfócitos B/imunologia , Camundongos , Imunoterapia Adotiva/métodos , Linhagem Celular Tumoral , Receptores de Antígenos Quiméricos/imunologia , Anticorpos de Domínio Único/imunologia , Anticorpos de Domínio Único/farmacologia , Linfócitos T/imunologia , Sistemas CRISPR-Cas , Feminino
4.
Angew Chem Int Ed Engl ; 63(23): e202405140, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38584136

RESUMO

Little is known about the structures and catalytic mechanisms of sesterterpene synthases (StTSs), which greatly hinders the structure-based engineering of StTSs for structural diversity expansion of sesterterpenes. We here report on the crystal structures of the terpene cyclization (TC) domains of two fungal StTSs: sesterfisherol synthase (NfSS) and sesterbrasiliatriene synthase (PbSS). Both TC structures contain benzyltriethylammonium chloride (BTAC), pyrophosphate (PPi), and magnesium ions (Mg2+), clearly defining the catalytic active sites. A combination of theory and experiments including carbocationic intermediates modeling, site-directed mutagenesis, and isotope labeling provided detailed insights into the structural basis for their catalytic mechanisms. Structure-based engineering of NfSS and PbSS resulted in the formation of 20 sesterterpenes including 13 new compounds and four pairs of epimers with different configurations at C18. These results expand the structural diversity of sesterterpenes and provide important insights for future synthetic biology research.


Assuntos
Sesterterpenos , Sesterterpenos/química , Sesterterpenos/metabolismo , Ciclização , Terpenos/metabolismo , Terpenos/química , Alquil e Aril Transferases/metabolismo , Alquil e Aril Transferases/química , Alquil e Aril Transferases/genética , Engenharia de Proteínas , Domínio Catalítico , Modelos Moleculares , Cristalografia por Raios X
5.
J Am Chem Soc ; 2023 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-37018048

RESUMO

The cyclization of farnesyl diphosphate (FPP) into highly strained polycyclic sesquiterpenes is challenging. We here determined the crystal structures of three sesquiterpene synthases (STSs, namely, BcBOT2, DbPROS, and CLM1) catalyzing the biosynthesis of the tricyclic sesquiterpenes presilphiperfolan-8ß-ol (1), Δ6-protoilludene (2), and longiborneol (3). All three STS structures contain a substrate mimic, the benzyltriethylammonium cation (BTAC), in their active sites, providing ideal templates for quantum mechanics/molecular mechanics (QM/MM) analyses toward their catalytic mechanisms. The QM/MM-based molecular dynamics (MD) simulations revealed the cascade reactions toward the enzyme products, and different key active site residues that play important roles in stabilizing reactive carbocation intermediates along the three pathways. Site-directed mutagenesis experiments confirmed the roles of these key residues and concomitantly resulted in 17 shunt products (4-20). Isotopic labeling experiments addressed the key hydride and methyl migrations toward the main and several shunt products. These combined methods provided deep insights into the catalytic mechanisms of the three STSs and demonstrated how the chemical space of STSs can rationally be expanded, which may facilitate applications in synthetic biology approaches toward pharmaceutical and perfumery agents.

6.
Macromol Rapid Commun ; 44(11): e2200778, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36404104

RESUMO

Covalent organic frameworks (COFs) are a type of crystalline porous polymers that possess ordered structures and eternal pores. Because of their unique structural characteristics and diverse functional groups, COFs have been used in various application fields, such as adsorption, catalysis, separation, ion conduction, and energy storage. Among COFs, the fluorine-containing COFs (fCOFs) have been developed for special applications by virtue of special physical and chemical properties resulting from fluorine element, which is a nonmetallic halogen element and possesses strong electronegativity. In the organic chemistry field, introducing fluorine into chemicals enables those chemicals to exhibit many interesting properties, and fluorine chemistry increasingly plays an important role in the history of chemical development. The introduction of fluorine in COFs can enhance the crystallinity, porosity, and stability of COFs, making COFs having superior performances and some new applications. In this review, the synthesis and application of fCOFs are systematically summarized. The application involves photocatalytic production of hydrogen peroxide, photocatalytic water splitting, electrocatalytic CO2 reduction, adsorption for different substances (H2 , pesticides, per-/polyfluoroalkyl substances, polybrominated diphenyl ethers, bisphenols, and positively charged organic dye molecules), oil-water separation, energy storage (e.g., zinc-ion batteries, lithium-sulfur batteries), and proton conduction. Perspectives of remaining challenges and possible directions for fCOFs are also discussed.


Assuntos
Flúor , Estruturas Metalorgânicas , Halogênios , Polímeros
7.
J Opt Soc Am A Opt Image Sci Vis ; 40(3): 637-644, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-37133048

RESUMO

Vortex X-waves with coupling effects of orbital angular momentum (OAM) and spatiotemporal invariance are introduced into the research of underwater wireless optical communication systems (UWOCSs). We establish the OAM probability density of vortex X-waves and channel capacity of UWOCS using Rytov approximation and correlation function. Furthermore, an in-depth analysis of OAM detection probability and channel capacity is performed on vortex X-waves carrying OAM in von Kármán oceanic turbulence with anisotropy. The results show that an increase in OAM quantum number results in a "hollow X" shape in the received plane, where the energy of vortex X-waves is injected into the lobes, reducing the received probability of the vortex X-waves transmitted to the receiving end. As the Bessel cone angle increases, the energy gradually concentrates toward the energy distribution center, and the vortex X-waves become more localized. Our research may trigger the development of UWOCS for bulk data transfer based on OAM encoding.

8.
Chem Soc Rev ; 51(2): 761-791, 2022 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-34989729

RESUMO

Porous organic polymers (POPs) composed of organic building units linked via covalent bonds are a class of lightweight porous network materials with high surface areas, tuneable pores, and designable components and structures. Owing to their well-preserved characteristics in terms of structure and composition, POPs applied as electrocatalysts have shown promising activity and achieved considerable advances in numerous electrocatalytic reactions, including the hydrogen evolution reaction, oxygen evolution reaction, oxygen reduction reaction, CO2 reduction reaction, N2 reduction reaction, nitrate/nitrite reduction reaction, nitrobenzene reduction reaction, hydrogen oxidation reaction, and benzyl alcohol oxidation reaction. Herein, we present a systematic overview of recent advances in the applications of POPs in these electrocatalytic reactions. The synthesis strategies, specific active sites, and catalytic mechanisms of POPs are summarized in this review. The fundamental principles of some electrocatalytic reactions are also concluded. We further discuss the current challenges of and perspectives on POPs for electrocatalytic applications. Meanwhile, the possible future directions are highlighted to afford guidelines for the development of efficient POP electrocatalysts.

9.
Angew Chem Int Ed Engl ; 62(42): e202310794, 2023 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-37596246

RESUMO

Covalent organic frameworks (COFs) with structural designability and tunability of photophysical properties enable them to be a promising class of organic luminescent materials by incorporating well-designed fluorescent units directly into the periodic skeletons. The photophysical properties of COFs are mainly affected by the structural features, which determine the conjugation degree, charge delocalization ability, and exciton dynamics of COFs. To understand the relationship between COF structures and their photophysical properties, two COFs with the same pyrene chromophore units but different linkages (imine or vinylene) were designed and synthesized. Interestingly, different linkages endow COFs with huge differences in solid-state photoluminescence quantum yield (PLQY) for imine- and vinylene-linked pyrene-based COFs, which possess PLQY values of 0.34 % and 15.43 %, respectively. The femtosecond-transient absorption spectra and time-dependent density functional theory reveal the different charge-transfer pathways in imine- and vinylene-linked COFs, which influence the exciton relaxation way and fluorescence intensity. In addition, an effective white-light device was obtained by coating the vinylene-linked COF on a light-emitting diode strip.

10.
Angew Chem Int Ed Engl ; 62(36): e202308523, 2023 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-37370248

RESUMO

Constructing a powerful photocatalytic system that can achieve the carbon dioxide (CO2 ) reduction half-reaction and the water (H2 O) oxidation half-reaction simultaneously is a very challenging but meaningful task. Herein, a porous material with a crystalline topological network, named viCOF-bpy-Re, was rationally synthesized by incorporating rhenium complexes as reductive sites and triazine ring structures as oxidative sites via robust -C=C- bond linkages. The charge-separation ability of viCOF-bpy-Re is promoted by low polarized π-bridges between rhenium complexes and triazine ring units, and the efficient charge-separation enables the photogenerated electron-hole pairs, followed by an intramolecular charge-transfer process, to form photogenerated electrons involved in CO2 reduction and photogenerated holes that participate in H2 O oxidation simultaneously. The viCOF-bpy-Re shows the highest catalytic photocatalytic carbon monoxide (CO) production rate (190.6 µmol g-1 h-1 with about 100 % selectivity) and oxygen (O2 ) evolution (90.2 µmol g-1 h-1 ) among all the porous catalysts in CO2 reduction with H2 O as sacrificial agents. Therefore, a powerful photocatalytic system was successfully achieved, and this catalytic system exhibited excellent stability in the catalysis process for 50 hours. The structure-function relationship was confirmed by femtosecond transient absorption spectroscopy and density functional theory calculations.

11.
J Biol Chem ; 297(1): 100822, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34029593

RESUMO

The fungal cyclohexadepsipeptides destruxins (DTXs), isaridins (ISDs), and isariins (ISRs) are nonribosomal peptides whose structures include a 19-membered ring composed of five amino acid residues and one α- or ß-hydroxy acid residue. These cyclohexadepsipeptides contain unusual nonproteinogenic amino acid-building blocks and possess a range of antiviral, antibacterial, and other activities. The biosynthetic gene clusters for ISDs and ISRs have not been identified, and the biosynthesis of the nonproteinogenic (3S)-methyl-l-proline residue, which is found in DTXs, ISDs, and many other natural products, lacks full characterization. In an ongoing effort to identify compounds that can inhibit the Zika virus (ZIKV), we examined the extract of marine-derived fungus Beauveria felina SX-6-22 and discovered 30 DTXs, ISDs, and ISRs (1-30) including seven new compounds (1-7). The anti-ZIKV assays showed that 9-12 and 16-18 possess inhibitory activities against ZIKV RNA replication and NS5 (nonstructural protein 5) production in ZIKV-infected A549 cells. We sequenced the genome of B. felina SX-6-22 and identified three biosynthetic gene clusters detx, isd and isr, which are responsible for the biosynthesis of DTXs, ISDs, and ISRs, respectively. Comparative analyses of the three gene clusters clarified the biosynthetic relationships among these cyclohexadepsipeptides. Finally, we characterized the entire biosynthesis of nonproteinogenic building block (3S)-methyl-l-proline. The Δ1-pyrroline-5-carboxylate reductases (P5CRs), also used in the biosynthesis of l-proline, were demonstrated to catalyze the final reduction step in (3S)-methyl-l-proline formation, suggesting potential cross talk between primary and secondary metabolisms. These results provide opportunities for biosynthetic pathway engineering to generate new anti-ZIKV cyclohexadepsipeptides.


Assuntos
Antivirais/farmacologia , Depsipeptídeos/farmacologia , Descoberta de Drogas , Prolina/biossíntese , Zika virus/efeitos dos fármacos , Antivirais/química , Bioensaio , Vias Biossintéticas/genética , Depsipeptídeos/química , Conformação Molecular , Família Multigênica
12.
J Opt Soc Am A Opt Image Sci Vis ; 39(4): 674-681, 2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35471393

RESUMO

Theoretical and experimental explorations have demonstrated that both anisotropy and unstable stratification exist in general ocean turbulence. Recent analyses of temporal broadening of ultrashort optical pulses in oceanic turbulence have adopted the assumptions that the propagation path in the z direction was isotropic, or turbulent cells are simply premised on circular symmetry in the xy plane. In this paper, circular symmetry of turbulent cells in the xy plane is no longer maintained, and two anisotropic factors describing the anisotropic scales in the xy plane are introduced to study the temporal broadening of ultrashort optical pulses. Moreover, unstable stratification of oceanic turbulence indicates the eddy diffusivities of temperature and salt are no longer equal. By Rytov approximation and the temporal-moments method, a new model is proposed for the temporal broadening of ultrashort optical pulse propagation in general ocean turbulence. We focus on the effects of asymmetric turbulent cells, unstable stratification, and other characteristics in general ocean turbulence on the temporal broadening. This work provides a theoretical basis for improving the transmission quality of ultrashort optical pulses and the performance of underwater optical communication systems.

13.
BMC Public Health ; 22(1): 91, 2022 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-35027030

RESUMO

BACKGROUND: As the emerging economies, the BRICS (Brazil, Russia, India, China, and South Africa) shared 61.58% of the global chronic respiratory diseases (CRD) deaths in 2017. This study aimed to assess the secular trends in CRD mortality and explore the effects of age, period, and cohort across main BRICS countries. METHODS: Data were obtained from the Global Burden of Disease Study (GBD) 2019 and analyzed using the age-period-cohort (APC) model to estimate period and cohort effects between 1990 and 2019. The net drifts, local drifts, longitudinal age curves, period/cohort rate ratios (RRs) were obtained through the APC model. RESULTS: In 2019, the CRD deaths across the BRICS were 2.39 (95%UI 1.95 to 2.84) million, accounting for 60.07% of global CRD deaths. Chronic obstructive pulmonary disease (COPD) and asthma remained the leading causes of CRD deaths. The age-standardized mortality rates (ASMR) have declined across the BRICS since 1990, with the most apparent decline in China. Meanwhile, the downward trends in CRD death counts were observed in China and Russia. The overall net drifts per year were obvious in China (-5.89%; -6.06% to -5.71%), and the local drift values were all below zero in all age groups for both sexes. The age effect of CRD presented increase with age, and the period and cohort RRs were following downward trends over time across countries. Similar trends were observed in COPD and asthma. The improvement of CRD mortality was the most obvious in China, especially in period and cohort effects. While South Africa showed the most rapid increase with age across all CRD categories, and the period and cohort effects were flat. CONCLUSIONS: BRICS accounted for a large proportion of CRD deaths, with China and India alone contributing more than half of the global CRD deaths. However, the declines in ASMR and improvements of period and cohort effects have been observed in both sexes and all age groups across main BRICS countries. China stands out for its remarkable reduction in CRD mortality and its experience may help reduce the burden of CRD in developing countries.


Assuntos
Asma , Doença Pulmonar Obstrutiva Crônica , Brasil , China/epidemiologia , Feminino , Carga Global da Doença , Humanos , Índia , Masculino , Federação Russa/epidemiologia , África do Sul/epidemiologia
14.
BMC Public Health ; 22(1): 760, 2022 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-35421975

RESUMO

BACKGROUND: Micromobility sharing platforms have involved skyrocketing numbers of users in multiple countries since 2010. However, few studies have examined the overall impact of the growing micromobility market on road injuries. METHOD: We use road injury data from the Global Burden of Disease Study database to examine the effect of age, period, and cohort on micromobility injury-related deaths and incidence. We compared four countries that vary in demographic background and road infrastructure. By comparing the countries, we analyzed the relationship between the trends in road injuries and these factors. RESULTS: We found an overall upward trend in micromobility injuries. A higher risk of micromobility-related injuries was witnessed in China and the US in 2015-2019, and people older than 45 showed a growing micromobility-related mortality and incidence rate in China, India, and the US. Cohorts after 1960 showed higher micromobility injury incidence risks in China and India, but the population born after 1990 in India showed a slightly lower risk compared to those before it. CONCLUSIONS: The boosted usage of micromobility devices explains these increasing trends. Road infrastructure and separated traffic ease the collisions from micromobility devices. The overall situation calls for improvement in legislation as well as road infrastructure.


Assuntos
Acidentes de Trânsito , Ferimentos e Lesões , China/epidemiologia , Estudos de Coortes , Humanos , Incidência , Japão , Estados Unidos/epidemiologia , Ferimentos e Lesões/epidemiologia
15.
Int J Neurosci ; : 1-9, 2022 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-35815432

RESUMO

Objective: Stroke is the leading cause of disability worldwide. Traditionally, doctors assess stroke rehabilitation assessment, which can be subjective. Therefore, an objective assessment method is required.Methods: In this context, we investigated the changes in brain functional connectivity patterns and corticomuscular coupling in stroke patients during rehabilitation. In this study, electroencephalogram (EEG) and electromyogram (EMG) of stroke patients were collected synchronously at baseline(BL), two weeks after BL, and four weeks after BL. A brain functional network was established, and the corticomuscular coupling relationship was calculated using phase transfer entropy (PTE).Results: We found that during the rehabilitation of stroke patients, the overall connection of the brain functional network was strengthened, and the network characteristic value increased. The average corticomuscular PTE appeared to first decrease and subsequently increase, and the PTE increase in the frontal lobe was significant.Value: In this study, PTE was used for the first time to analyze the relationship between EEG signals in patients with hemiplegia. We believe that our findings contribute to evaluating the rehabilitation of stroke patients with hemiplegia.

16.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 47(2): 226-237, 2022 Feb 28.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-35545413

RESUMO

OBJECTIVES: Root canal therapy is the most effective and common method for pulpitis and periapical periodontitis. During the root canal preparation, chemical irrigation plays a key role. However, sodium hypochlorite (NaOCl), the widely used irrigation fluid, may impact the bonding strength between dentin and restorative material meanwhile sterilization and dissolving. Therefore, it's important to explore the influence of NaOCl on the adhesion between dentin and restoration materials to ensure clinical efficacy. This study aims to explore the effect of NaOCl on dentine adhesion and evaluate the effect of dentine adhesion induced by sodium erythorbate (ERY), and to provide clinical guidance on dentin bonding after root canal therapy. METHODS: Seventy freshly complete extracted human third molars aged 18-33 years old, without caries and restorations were selected. A diamond saw was used under running water to achieve dentine fragments which were divided into 10 groups with 14 fragments in each group: 2 control [deionized water (DW)±10% ERY] and 8 experimental groups (0.5%, 1%, 2.5%, and 5.25% NaOCl±10% ERY). The dentine specimens in the control group (treated with DW) and the experimental groups (treated with 0.5% NaOCl, 1% NaOCl, 2.5% NaOCl, and 5.25% NaOCl) were immersed for 20 min using corresponding solutions which were renewed every 5 min. The other 5 groups were immersed in 10% ERY for 5 min after an initial washing with DW for 1 min. Then, we selected 4 dentine fragments from all 14 fragments in each group and the numbers and diameters of opening dentinal tubules were observed under scanning electron microscope (SEM). The other 10 dentine fragments from each group were used to make adhesive samples by using self-etch adhesive wand composite resin. All the above adhesive samples were sectioned perpendicular to the bonded interface into 20 slabs with a cross-sectional area of 1 mm×1 mm using a diamond saw under the cooling water, and then the morphology of 10 slabs in each group's bonding interface was observed from aspects of formation of resin tags, depth of tags in dentin, and formation of hybrid layer under SEM. The other 10 slabs of each group's microtensile bond strength and failure modes were also analyzed. RESULTS: Among the 0.5% NaOCl, 1% NaOCl, 2.5% NaOCl, and 5.25% NaOCl groups, the number and diameter of patent dentinal tubules gradually increased with the rise of concentration of NaOCl solution (all P<0.05). Among the DW, 0.5% NaOCl, 1% NaOCl, 2.5% NaOCl, and 5.25% NaOCl groups, the number and diameter of patent dentinal tubules increased after using ERY, but without significant difference (all P>0.05). Among the DW, 0.5% NaOCl, 1% NaOCl, and 2.5% NaOCl groups, the scores of formation of resin tags under SEM gradually increased with the increase of concentration of NaOCl solution, while the score in the 5.25% NaOCl group decreased significantly compared with the score of the 2.5% NaOCl group (P<0.05). There was no significant difference between using 10% ERY groups and without using 10% ERY groups (all P>0.05). The scores of length of the tags under SEM in the 5.25% NaOCl group was significantly higher than the scores of DW, 0.5% NaOCl, and 1% NaOCl groups (all P<0.05), and it was also higher than the score of the 2.5% NaOCl group, but without significant difference (P>0.05). There was no significant difference between using 10% ERY groups and without using 10% ERY groups (P>0.05). The scores of formation of hybrid layer under SEM in the 2.5% NaOCl and 5.25% NaOCl groups significantly decreased compared with the score of the DW group (all P<0.05). There were significant differences between the 2.5% NaOCl±10% ERY groups and between the 5.25% NaOCl±10% ERY groups (all P<0.05). Microtensile bond strength was greater in the 0.5% NaOCl, 1% NaOCl, and 2.5% NaOCl groups, but lower in the 5.25% NaOCl group than that in the DW group (all P<0.05). There were significant differences between the 2.5% NaOCl±10% ERY groups and between the 5.25% NaOCl±10% ERY groups (all P<0.05). The incidence of type "Adhesive" of failure modes in the 5.25% NaOCl group was significantly higher than that in other groups (all P<0.05), while the incidence of type "Adhesive" in the 5.25% NaOCl+10% ERY group was lower than that in the 5.25% NaOCl group (P<0.05). CONCLUSIONS: The bonding strength to dentine increases with the increase of NaOCl concentration when the concentration lower than 2.5%; whereas it is decreased at a higher concentration (such as 5.25%). 10% ERY has a definite recovery effect on attenuated bonding strength to 5.25% NaOCl-treated dentine.


Assuntos
Colagem Dentária , Hipoclorito de Sódio , Adolescente , Adulto , Ácido Ascórbico , Dentina , Adesivos Dentinários/química , Adesivos Dentinários/farmacologia , Diamante/farmacologia , Humanos , Teste de Materiais , Microscopia Eletrônica de Varredura , Cimentos de Resina/química , Cimentos de Resina/farmacologia , Hipoclorito de Sódio/química , Hipoclorito de Sódio/farmacologia , Resistência à Tração , Água/farmacologia , Adulto Jovem
17.
Angew Chem Int Ed Engl ; 61(36): e202209785, 2022 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-35819825

RESUMO

The crystal structures of cattleyene synthase (apo-CyS), and CyS complexed with geranylgeranyl pyrophosphate (GGPP) were solved. The CySC59A variant exhibited an increased production of cattleyene and other diterpenes with diverse skeletons. Its structure showed a widened active site cavity explaining the relaxed selectivity. Isotopic labeling experiments revealed a remarkable cyclization mechanism involving several skeletal rearrangements for one of the novel diterpenes.


Assuntos
Diterpenos , Domínio Catalítico , Ciclização , Diterpenos/química , Mutagênese
18.
J Cell Physiol ; 236(5): 3536-3551, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-32996162

RESUMO

Orchitis is one of the leading causes of male animal infertility and is associated with inflammatory reactions caused by the bacterium. It has been reported that there is a mutual coupling effect between endoplasmic reticulum stress (ERS) and inflammatory response. Our studies showed that lipopolysaccharide (LPS) could cause testicular damages, apoptosis, ERS, and inflammatory responses in spermatogonial stem cells (SSCs); ERS-related apoptosis proteins were activated and the expression of ERS genes was significantly upregulated; meanwhile, the expression of Toll-like receptor 4 and inflammation factors was apparently increased with LPS treatment. Moreover, melatonin (MEL) could rescue testicular damage, and significantly inhibited the expression of ERS-related apoptosis genes, ERS markers, and inflammatory factors in SSCs and MEL played repairing and anti-infection roles in LPS-induced testicular damage. Therefore, MEL may be used as a drug to prevent and control bacterial infections in male reproductive systems. However, the specific molecular mechanism of MEL to resist ERS and inflammatory response remains to be further studied.


Assuntos
Células-Tronco Germinativas Adultas/patologia , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Inflamação/patologia , Melatonina/farmacologia , Células-Tronco Germinativas Adultas/efeitos dos fármacos , Células-Tronco Germinativas Adultas/metabolismo , Animais , Apoptose/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Lipopolissacarídeos , Masculino , Camundongos , Modelos Biológicos , Receptores de Melatonina/metabolismo , Testículo/efeitos dos fármacos , Testículo/patologia
19.
J Cell Physiol ; 236(2): 1481-1493, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32692417

RESUMO

Spermatogenesis is a complex process that originates from and depends on the spermatogonial stem cells (SSCs). The number of SSCs is rare, which makes the separation and enrichment of SSCs difficult and inefficient. The transcription factor PAX7 maintains fertility in normal spermatogenesis in mice. However, for large animals, much less is known about the SSCs' self-renewal regulation, especially in dairy goats. We isolated and enriched the CD49f-positive and negative dairy goat testicular cells by magnetic-activated cell sorting strategies. The RNA- sequencing and experimental data revealed that cells with a high CD49f and PAX7 expression are undifferentiated spermatogonia in goat testis. Our findings indicated that ZBTB16 (PLZF), PAX7, LIN28A, BMPR1B, FGFR1, and FOXO1 were expressed higher in CD49f-positive cells as compared to negative cells and goat fibroblasts cells. The expression and distribution of PAX7 in dairy goat also have been detected, which gradually decreased in testis tissue along with the increasing age. When the PAX7 gene was overexpressed in dairy goat immortal mGSCs-I-SB germ cell lines, the expression of PLZF, GFRα1, ID4, and OCT4 was upregulated. Together, our data demonstrated that there is a subset of spermatogonial stem cells with a high expression of PAX7 among the CD49f+ spermatogonia, and PAX7 can maintain the self-renewal of CD49f-positive SSCs.


Assuntos
Integrina alfa6/genética , Fator de Transcrição PAX7/genética , Espermatogênese/genética , Testículo/crescimento & desenvolvimento , Animais , Diferenciação Celular/genética , Proliferação de Células/genética , Autorrenovação Celular/genética , Regulação da Expressão Gênica no Desenvolvimento/genética , Cabras/genética , Cabras/crescimento & desenvolvimento , Masculino , MicroRNAs/genética , Proteína com Dedos de Zinco da Leucemia Promielocítica/genética , Espermatogônias/crescimento & desenvolvimento , Células-Tronco/citologia , Células-Tronco/metabolismo , Testículo/metabolismo
20.
Opt Lett ; 46(21): 5461-5464, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34724501

RESUMO

In this study, we introduce the phase correlation arc of an orbital angular momentum (OAM) beam to investigate the evolution of OAM entanglement. We reveal that the entanglement decay of all OAM states of Laguerre-Gaussian modes in atmospheric turbulence is universal via both numerical predictions and experimental data. A similar evolution law is also theoretically confirmed to exist in Bessel-Gaussian modes. Finally, by using the phase correlation arc, the precise formula of the decay distance dependence on the OAM number is derived, and it exhibits excellent agreement with previous experimental conclusions.

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