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1.
Reprod Biol Endocrinol ; 22(1): 133, 2024 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-39478547

RESUMO

BACKGROUND: Epidemiological studies have reported that polymorphisms of folate-metabolizing genes have a significant impact on male infertility. However, the results of published studies have come to different conclusions. OBJECTIVE: To determine an association between folate-metabolizing gene polymorphisms and the risk of male infertility. METHODS: The meta-analysis was conducted according to the PRISMA 2020 statement. The protocol was registered with PROSPERO (CRD42023412251). Studies were searched from PubMed, Google Scholar, Embase, Scopus, and the Cochrane Library up to 24st October2023. Articles that satisfied the inclusion criteria were evaluated for their quality using the Newcastle-Ottawa Scale. Data were extracted from the eligible studies and were analyzed for pooled up odds ratio (OR) with 95% confidence interval (CI). Meta-analysis was conducted using STATA 12. RESULTS: Forty-six case-control studies were included in the meta-analysis which comprised 20,639 participants. The pooled analysis revealed that the MTHFR C677T polymorphism was significantly associated with male infertility and abnormospermia.Three-fifths of the model showed there was a significant association between the MTR A2756G polymorphism and male infertility. Both MTHFR A1298C and MTRR A66G polymorphisms were not significantly associated with male fertility. Furthermore, subgroup analysis revealed a significant association between the MTHFR C677T polymorphism and male fertility in Asian countries. CONCLUSION: This meta-analysis suggests that the MTHFR C677T and MTR A2756G polymorphisms may be a potential risk factor for male infertility.


Assuntos
5-Metiltetra-Hidrofolato-Homocisteína S-Metiltransferase , Ferredoxina-NADP Redutase , Predisposição Genética para Doença , Infertilidade Masculina , Metilenotetra-Hidrofolato Redutase (NADPH2) , Polimorfismo de Nucleotídeo Único , Humanos , Masculino , Infertilidade Masculina/genética , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Predisposição Genética para Doença/genética , 5-Metiltetra-Hidrofolato-Homocisteína S-Metiltransferase/genética , Ferredoxina-NADP Redutase/genética , Estudos de Casos e Controles , Fatores de Risco
2.
Eur J Obstet Gynecol Reprod Biol ; 299: 54-61, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38838387

RESUMO

OBJECTIVE: To evaluate the effect of insulin resistance (IR) on in vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI) outcomes in patients with polycystic ovary syndrome (PCOS). STUDY DESIGN: PubMed, Google Scholar,Web of Science, Embase, Scopus and the Cochrane Library were searched to identify relevant studies. A total of 6,137 PCOS women undergoing IVF/ICSI with or without IR were included in the systematic review and meta-analysis. RESULTS: The systematic review and meta-analysis included twelve observational studies that were free from inherent bias. When comparing PCOS women undergoing IVF/ICSI, the IR and non-IR groups did not show significant differences in oocytes retrieved (WMD = -0.63, 95 % CI: -2.37 to 1.12, P = 0. 483), fertilization rate (WMD = 1.01, 95 % CI: -0.66 to 2.67, P = 0.236; OR = 0.97, 95 % CI: 0.79 to 1.19, P = 0.783), and live birth rate (OR = 1.02, 95 % CI: 0.78 to 1.33, P = 0.892). However, the group with IR had a lower number of MII oocytes (WMD = -1.07, 95 % CI: -1.54 to -0.59, P < 0.001), total embryos (WMD = -1.37, 95 % CI: -1. 78 to -0.95, P < 0.001), and clinical pregnancy rate (OR = 0.77, 95 % CI: 0.59 to 0.99, P = 0.042), as well as a higher miscarriage rate (OR = 1.11, 95 % CI: 1.02 to 1.22, P = 0.017) compared to the non-IR group. CONCLUSION: In women with PCOS, IR had a negative impact on IVF/ICSI outcomes. To obtain more favourable empirical support, larger studies are necessary.


Assuntos
Fertilização in vitro , Resistência à Insulina , Síndrome do Ovário Policístico , Taxa de Gravidez , Injeções de Esperma Intracitoplásmicas , Humanos , Síndrome do Ovário Policístico/complicações , Síndrome do Ovário Policístico/terapia , Feminino , Gravidez , Fertilização in vitro/métodos , Infertilidade Feminina/terapia
3.
Rev Sci Instrum ; 95(3)2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38497835

RESUMO

Two-dimensional electronic spectroscopy (2DES) can be implemented with different geometries, e.g., BOXCARS, collinear, and pump-probe geometries. The pump-probe geometry has the advantage of overlapping only two beams and reducing phase cycling steps. However, its applications are typically limited to observing the dynamics with single-quantum coherence and population, leaving the challenge to measure the dynamics of the double-quantum (2Q) coherence, which reflects the many-body interactions. We demonstrate an experimental technique in 2DES under pump-probe geometry with a designed pulse sequence and the signal processing method to extract 2Q coherence. In the designed pulse sequence, with the probe pulse arriving earlier than the pump pulses, our measured signal includes the 2Q signal as well as the zero-quantum signal. With phase cycling and data processing using causality enforcement, we extract the 2Q signal. The proposal is demonstrated with rubidium atoms. We observe the collective resonances of two-body dipole-dipole interactions in both the D1 and D2 lines.

4.
Adv Mater ; 36(19): e2312352, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38301140

RESUMO

Developing artificial ion transport systems, which process complicated information and step-wise regulate properties, is essential for deeply comprehending the subtle dynamic behaviors of natural channel proteins (NCPs). Here a photo-controlled logic-gated K+ channel based on single-chain random heteropolymers containing molecular motors, exhibiting multi-core processor-like properties to step-wise control ion transport is reported. Designed with oxygen, deoxygenation, and different wavelengths of light as input signals, complicated logical circuits comprising "YES", "AND", "OR" and "NOT" gate components are established. Implementing these logical circuits with K+ transport efficiencies as output signals, multiple state transitions including "ON", "Partially OFF" and "Totally OFF" in liposomes and cancer cells are realized, further causing step-wise anticancer treatments. Dramatic K+ efflux in the "ON" state (decrease by 50% within 7 min) significantly induces cancer cell apoptosis. This integrated logic-gated strategy will be expanded toward understanding the delicate mechanism underlying NCPs and treating cancer or other diseases is expected.


Assuntos
Apoptose , Luz , Humanos , Potássio/metabolismo , Potássio/química , Canais de Potássio/metabolismo , Linhagem Celular Tumoral , Ativação do Canal Iônico , Lipossomos/química , Lipossomos/metabolismo , Neoplasias/metabolismo , Neoplasias/patologia , Lógica
5.
Opt Express ; 32(3): 2929-2941, 2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38297529

RESUMO

Developing from transient absorption (TA) spectroscopy, two-dimensional (2D) spectroscopy with pump-probe geometry has emerged as a versatile approach for alleviating the difficulty in implementing 2D spectroscopy with other geometries. However, the presence of cross-phase modulation (XPM) in TA spectroscopy introduces significant spectral distortions, particularly when the pump and probe pulses overlap. We demonstrate that this phenomenon is extended to the 2D spectroscopy with pump-probe geometry and the XPM is induced by the interference of the two pump pulses. We present the oscillatory behavior of XPM in the 2D spectrum and its displacement with respect to the waiting time delay through both experimental measurements and numerical simulations. Additionally, we explore the influence of probe pulse chirp on XPM and discover that by compressing the chirp, the impact of XPM on the desired signal can be reduced.

6.
Polymers (Basel) ; 15(18)2023 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-37765577

RESUMO

The radiation effect of materials is very important and directly related to the safety and reliability of nuclear reactors. Polymer materials, one of the indispensable materials in nuclear power equipment, must withstand the ordeal of high-energy ionizing rays. In this work, through screening different γ-ray dose irradiation conditions, we systematically and comprehensively study the changes in the structure and properties of nitrile butadiene rubber (NBR) before and after γ-ray static irradiation at a high dose rate, and master the rule and mechanism of the γ-ray static irradiation effect of these polymer materials. The mapping relationship between the macroscopic properties, microstructure, and irradiation dose of NBR is accurately characterized. With an increase in total irradiation dose, the C=C double bond reaction occurs, and the C≡N bond, C=C, and C=O participate in the hyper crosslinking reaction. The glass transition temperature (Tg) increases with the cumulative irradiation amount. With the increased total irradiation amount, the degree of rubber cross-linking increases, causing an increased crystallinity and decomposition temperature. A growing amount of gamma irradiation causes the mechanical properties of the rubber to degrade simultaneously, increasing the shore hardness while decreasing the tensile strength and ultimate elongation at break. When the cumulative amount reaches 1 MGy, the ultimate elongation at break decreases significantly. A cumulative dose of radiation resistance of 4 MGy can be achieved by the samples. This work can provide theoretical and experimental support for the long-term stability of nitrile butadiene rubber and its derivatives in nuclear radiation fields and space radiation conditions.

7.
Chem Sci ; 14(22): 6039-6044, 2023 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-37293632

RESUMO

Inspired by nature, it is of significant importance to design and construct biomimetic signaling systems to mimic natural signal transduction. Herein, we report an azobenzene/α-cyclodextrin (α-CD)-based signal transduction system with three functional modules: a light-responsive headgroup, lipid-anchored group, pro-catalyst tailgroup. The transducer can be inserted into the vesicular membrane to trigger the transmembrane translocation of molecules under the activation of light, forming a ribonuclease-like effector site and leading to the transphosphorylation of the RNA model substrate inside the vesicles. Moreover, the transphosphorylation process can be reversibly turned 'ON/OFF' over multiple cycles by the activation and deactivation of the pro-catalyst. This artificial photo-controlled signal transduction successfully constructs a signal responsive catalysis system across the membrane to utilize light to reversibly control the internal transphosphorylation process of an RNA model substrate, which might provide a new strategy for future design to utilize exogenous signals for implementing endogenous enzyme manipulation and gene regulation.

8.
Clin Exp Med ; 23(7): 4021-4031, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37354366

RESUMO

Liver fibrosis is a serious stage of chronic liver injury. Inhibition of hepatic stellate cells activation and hepatocytes apoptosis is important measures in the treatment of liver fibrosis. Studies have shown that exosomes are involved in regulating the information transmission between cells, but there are few studies on the interaction between exosomes from HSC and hepatocytes. This study screened miRNAs with significant differences related to liver fibrosis in the database. Then, we activated HSC applying transforming growth factor ß1 (TGF-ß1) and collected exosomes. The expression of miRNA in HSC-derived exosomes was verified by quantitative real-time PCR (qRT-PCR). The results of cell function test showed that HSC-derived exocrine miRNA-99a-5p could inhibit hepatocytes proliferation and promote hepatocytes apoptosis. Conversely, inhibition of miRNA-99a-5p can promote hepatocytes proliferation and inhibit apoptosis. Target gene prediction and luciferase assay show that miRNA can specifically bind to BMPR2 site sequence. In addition, we also detected the expression of BMPR2 and apoptosis-related protein by qRT-PCR and Western blot (WB). In conclusion, this study demonstrates that HSC-derived exocrine miRNA-99a-5p can promote hepatocytes apoptosis and participate in the process of liver fibrosis by targeting BMPR2. Our findings highlight the therapeutic potential of HSC-derived exocrine miRNA-99a-5p in hepatic fibrosis.


Assuntos
Exossomos , MicroRNAs , Humanos , Células Estreladas do Fígado , Exossomos/genética , Cirrose Hepática/genética , Hepatócitos/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Apoptose , Receptores de Proteínas Morfogenéticas Ósseas Tipo II/metabolismo
9.
Chemistry ; 29(25): e202300044, 2023 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-36723493

RESUMO

Bilayer membranes that enhance the stability of the cell are essential for cell survival, separating and protecting the interior of the cell from its external environment. Membrane-based channel proteins are crucial for sustaining cellular activities. However, dysfunction of these proteins would induce serial channelopathies, which could be substituted by artificial ion channel analogs. Crown ethers (CEs) are widely studied in the area of artificial ion channels owing to their intrinsic host-guest interaction with different kinds of organic and inorganic ions. Other advantages such as lower price, chemical stability, and easier modification also make CE a research hotspot in the field of synthetic transmembrane nanopores. And numerous CEs-based membrane-active synthetic ion channels were designed and fabricated in the past decades. Herein, the recent progress of CEs-based synthetic ion transporters has been comprehensively summarized in this review, including their design principles, functional mechanisms, controllable properties, and biomedical applications. Furthermore, this review has been concluded by discussing the future opportunities and challenges facing this research field. It is anticipated that this review could offer some inspiration for the future fabrication of novel CEs-derived ion transporters with more advanced structures, properties, and practical applications.


Assuntos
Éteres de Coroa , Nanoporos , Éteres de Coroa/química , Canais Iônicos/química , Íons
10.
Angew Chem Int Ed Engl ; 61(42): e202210214, 2022 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-36039469

RESUMO

A series of single-chain random heteropolymer (RHP)-derived artificial ion channels with both high K+ selectivity and controllable pH-gated behaviors were fabricated by a facile "one-pot" polymerization method. The benzo-18-crown-6 moieties appended on lateral chains of RHPs can form ion-permeable nanopores and transport K+ over Na+ through the lipid bilayers. The ion permeation selectivity was significantly enhanced by incorporating a cholesterol group to serve as a membrane anchor. Interestingly, similar to natural gated protein channels, on-off switchable characteristics were also realized by integrating an additional acid-sensitive alkylamine group into the RHP-derived channel. The unique design strategies have endowed the RHP-derived ion channels with facile synthetic procedures, desirable membrane compatibility, high K+ selectivity, and tunable pH-gated properties. This work provides an entry point for future design of novel functional nanochannels.


Assuntos
Bicamadas Lipídicas , Sódio , Concentração de Íons de Hidrogênio , Canais Iônicos , Polímeros
11.
Chem Commun (Camb) ; 58(38): 5725-5728, 2022 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-35441622

RESUMO

An artificial signal transduction model with a supramolecular recognition headgroup, a membrane anchoring group, and a pro-enzyme catalysis endgroup was constructed. The transmembrane translocation of the transducer can be reversibly regulated by competitive host-guest complexations as an input signal to control an enzyme reaction inside the lipid vesicles.


Assuntos
Transdução de Sinais , Catálise
12.
Angew Chem Int Ed Engl ; 61(10): e202114323, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-34941015

RESUMO

Efficient and long-range exciton transport is critical for photosynthesis and opto-electronic devices, and for triplet-harvesting materials, triplet exciton diffusion length ( L D ) and coefficient ( D ) are key parameters in determining their performances. Herein, we observed that PtII and PdII organometallic nanowires exhibit long-range anisotropic triplet exciton LD of 5-7 µm along the M-M direction using direct photoluminescence (PL) imaging technique by low-power continuous wave (CW) laser excitation. At room temperature, via a combined triplet-triplet annihilation (TTA) analysis and spatial PL imaging, an efficient triplet exciton diffusion was observed for the PtII and PdII nanowires with extended close M-M contact, while is absent in nanowires without close M-M contact. Two-dimensional electronic spectroscopy (2DES) and calculations revealed a significant contribution of the delocalized 1/3 [dσ*(M-M)→π*] excited state during the exciton diffusion modulated by the M-M distance.

13.
Nano Lett ; 21(24): 10462-10468, 2021 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-34860025

RESUMO

Natural protein channels have evolved with exquisite structures to transport ions selectively and rapidly. Learning from nature to construct biomimetic artificial channels is always challenging. Herein we present a unimolecular transmembrane proton channel by quinoline-derived helix, which exhibited highly selective and ultrafast proton transport behaviors. This helix-based channel possesses a small luminal cavity of 1 Å in diameter, which could efficiently reject the permeation of cations, anions or water molecules but only permits the translocation of protons owing to the size effect. The proton flow rate exceeded 107 H+ s-1 channel-1 and reached the same magnitude with gramicidin A. Mechanism investigation revealed that the directionally arrayed NH-chain inside the synthetic channel played a pivotal role during the proton flux. This work not only presented a helix-based channel with the smallest observable nanopore, but also unveiled an unexplored pathway for realizing efficient transport of protons via the consecutive NH-chain.


Assuntos
Canais Iônicos , Prótons , Gramicidina/química , Canais Iônicos/química , Íons , Água/química
14.
Polymers (Basel) ; 13(24)2021 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-34960914

RESUMO

Smart hydrogels are typical functional soft materials, but their functional and mechanical properties are compromised upon micro- or macro-mechanical damage. In contrast, hydrogels with self-healing properties overcome this limitation. Herein, a dual dynamic bind, cross-linked, self-healing protein hydrogel is prepared, based on Schiff base bonds and diselenide bonds. The Schiff base bond is a typical dynamic covalent bond and the diselenide bond is an emerging dynamic covalent bond with a visible light response, which gives the resulting hydrogel a dual response in visible light and a desirable self-healing ability. The diselenide-containing protein hydrogels were biocompatible due to the fact that their main component was protein. In addition, the hydrogels loaded with glucose oxidase (GOx) could be transformed into sols in glucose solution due to the sensitive response of the diselenide bonds to the generated hydrogen peroxide (H2O2) by enzymatic catalysis. This work demonstrated a diselenide-containing protein hydrogel that could efficiently self-heal up to nearly 100% without compromising their mechanical properties under visible light at room temperature.

15.
ACS Cent Sci ; 7(11): 1787-1797, 2021 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-34841053

RESUMO

Applying an asymmetric strategy to construct non-fullerene small-molecule acceptors (NFSMAs) in organic solar cells (OSCs) plays a vital role in the development of organic photovoltaic materials. In the past several years, taking advantage of the larger dipole moment and stronger intermolecular interactions, asymmetric NFSMAs have witnessed tremendous progress in OSCs with a power conversion efficiency of over 18%. From a structural point of view, besides the possible changes in the conformation effect on molecular packing, asymmetric acceptors can also achieve a balance between the solubility and the crystallinity. Herein, we systematically investigate the structure-property-performance relationships of asymmetric NFSMAs that have recently emerged and try to clarify the feasibility and practicality of an asymmetric strategy for the design of higher-performance NFSMAs. Finally, we put forward our views and a concise outlook on the asymmetric strategy.

16.
Mitochondrial DNA B Resour ; 6(11): 3130-3131, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34651078

RESUMO

Elaeocarpus decipiens F. B. Forbes and Hemsl is an evergreen tree native to East Asia. Here, we sequenced and reported the complete chloroplast genome of E. decipiens for the first time. In the present work, the complete chloroplast (cp) genome sequence of E. decipiens was characterized by Illumina pair-end sequencing. The genome was 158,148 bp in total length, including a large single-copy (LSC) region of 85,702 bp, a small single-copy (SSC) region of 17,672 bp, and a pair of invert repeats (IR) regions of 27,387 bp. The plastid genome contained 142 genes including 97 protein-coding genes, 37 tRNA genes, and eight rRNA genes. Phylogenetic analysis based on 13 chloroplast genomes indicates that E. decipiens is closely related to Elaeocarpus bracean in Elaeocarpacea.

17.
Molecules ; 26(18)2021 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-34577080

RESUMO

The selective disruption of nutritional supplements and the metabolic routes of cancer cells offer a promising opportunity for more efficient cancer therapeutics. Herein, a biomimetic cascade polymer nanoreactor (GOx/CAT-NC) was fabricated by encapsulating glucose oxidase (GOx) and catalase (CAT) in a porphyrin polymer nanocapsule for combined starvation and photodynamic anticancer therapy. Internalized by cancer cells, the GOx/CAT-NCs facilitate microenvironmental oxidation by catalyzing endogenous H2O2 to form O2, thereby accelerating intracellular glucose catabolism and enhancing cytotoxic singlet oxygen (1O2) production with infrared irradiation. The GOx/CAT-NCs have demonstrated synergistic advantages in long-term starvation therapy and powerful photodynamic therapy (PDT) in cancer treatment, which inhibits tumor cells at more than twice the rate of starvation therapy alone. The biomimetic polymer nanoreactor will further contribute to the advancement of complementary modes of spatiotemporal control of cancer therapy.


Assuntos
Nanopartículas/química , Neoplasias/terapia , Fotoquimioterapia/métodos , Polímeros/química , Animais , Biomimética , Catalase/química , Catalase/farmacologia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Glucose Oxidase/química , Glucose Oxidase/farmacologia , Humanos , Peróxido de Hidrogênio/metabolismo , Raios Infravermelhos , Camundongos , Polímeros/síntese química , Porfirinas/síntese química , Porfirinas/química , Oxigênio Singlete/metabolismo , Oxigênio Singlete/farmacologia
18.
Molecules ; 26(11)2021 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-34072932

RESUMO

In the past few decades, enormous efforts have been made to synthesize covalent polymer nano/microstructured materials with specific morphologies, due to the relationship between their structures and functions. Up to now, the formation of most of these structures often requires either templates or preorganization in order to construct a specific structure before, and then the subsequent removal of previous templates to form a desired structure, on account of the lack of "self-error-correcting" properties of reversible interactions in polymers. The above processes are time-consuming and tedious. A template-free, self-assembled strategy as a "bottom-up" route to fabricate well-defined nano/microstructures remains a challenge. Herein, we introduce the recent progress in template-free, self-assembled nano/microstructures formed by covalent two-dimensional (2D) polymers, such as polymer capsules, polymer films, polymer tubes and polymer rings.

19.
J Phys Chem Lett ; 12(10): 2555-2561, 2021 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-33683894

RESUMO

Excitons in monolayer transition metal dichalcogenides (TMDs) provide a paradigm of composite Boson in a two-dimensional system. This Letter reports a photoluminescence and reflectance study of excitons in monolayer molybdenum diselenide (MoSe2) with electrostatic gating. We observe the repulsive and attractive Fermi polaron modes of the band edge exciton, its excited state, and the spin-off excitons, which the simple three-particle trion model is insufficient to explain. The contrasting energy shift between the exciton and charge-bound excitons (repulsive and attractive polaron modes) and the remarkably different gate dependence of the polaron energy splitting between the ground state and the excited state excitons unambiguously support the Fermi polaron picture for excitons in monolayer TMDs.

20.
J Am Chem Soc ; 143(9): 3284-3288, 2021 03 10.
Artigo em Inglês | MEDLINE | ID: mdl-33645973

RESUMO

Small molecules that independently perform natural channel-like functions show greatly potential in the treatment of human diseases. Taking advantage of aromatic helical scaffolds, we develop a kind of foldamer-based ion channels with lumen size varying from 3.8 to 2.3 Å through a sequence substitution strategy. Our results clearly elucidate the importance of channel size in ion transport selectivity in molecular detail, eventually leading to the discoveries of the best artificial K+ channel by far and a rare sodium-preferential channel as well. High K+ selectivity and transport activity together make foldamers promising in therapeutic applications.


Assuntos
Materiais Biomiméticos/química , Transporte de Íons , Oxidiazóis/química , Potássio/metabolismo , Piridinas/química , Sódio/metabolismo , Bicamadas Lipídicas/metabolismo , Conformação Molecular , Canais de Potássio/química , Canais de Sódio/química
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