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1.
Angew Chem Int Ed Engl ; : e202405140, 2024 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-38584136

RESUMEN

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.

2.
Materials (Basel) ; 17(6)2024 Mar 09.
Artículo en Inglés | MEDLINE | ID: mdl-38541422

RESUMEN

Al-based foams have drawn increasing attention from industry due to their integration of structure and functional properties. However, large-sized Al-based foams still cannot be homogeneously strengthened by long-time aging due to their low thermal conductivity. In this study, we proposed an age-hardening approach that was applied in large-sized Al-0.16Sc-0.17Zr (wt.%) foams via micro-alloying with Zr and Ti compared with Al-0.21Sc foams; it not only achieved homogeneous strength by long-term aging but also reduced the cost of the alloy by substituting Zr and Ti for the more expensive Sc content. The results show that the Al3(Sc, Zr, Ti) phase with a core-shell structure as a crucial precipitation strengthening phase by micro-alloying with Zr and Ti was less prone to coarsening after a prolonged aging heat treatment. Therefore, the yielding strength of Al-Sc foam micro-alloying with Zr and Ti remained almost unchanged after a maximum aging time of 1440 h due to less coarsening precipitate, which is consistent with the results of mechanical experiments. These findings provide a new way for the heat treatment strengthening of large-sized Al-based foams, thus promoting their industrial applications.

3.
Int Med Case Rep J ; 17: 167-175, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38504721

RESUMEN

Introduction: Pancreatic cancer (PC) is among the deadliest malignancies. Kidney cancer (KC) is a common malignancy globally. Chemo- or radio-therapies are not very effective to control PC or KC, and overdoses often cause severe site reactions to the patients. As a result, novel treatment strategies with high efficacy but without toxic side effects are urgently desired. Secoisolariciresinol diglucoside (SDG) belongs to plant lignans with potential anticancer activities, but clinical evidence is not available in PC or KC treatment. Patient Concerns: We report a rare case of an 83-year-old female patient with pancreatic and kidney occupying lesions that lacked the conditions to receive surgery or chemo- or radiotherapy. Diagnosis: Pancreatic and kidney cancers. Interventions: We gave dietary SDG to the patient as the only therapeutics. Outcomes: SDG effectively halted progression of both PC and KC. All clinical manifestations, including bad insomnia, loss of appetite, stomach symptoms, and skin itching over the whole body, all disappeared. The initial massive macroscopic hematuria became microscopic and infrequent, and other laboratory results also gradually returned to normal. Most of the cancer biomarkers, initially high such as CEA, CA199, CA724, CA125, came down rapidly, among which CA199 changed most radically. This patient has had progression-free survival of one year so far. Conclusion: These results demonstrate the potent inhibitory effects of SDG on PC and KC of this patient and provide promising novel therapeutics for refractory malignant tumors.

4.
Opt Express ; 32(4): 4887-4901, 2024 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-38439229

RESUMEN

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.

5.
Stress Biol ; 4(1): 9, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38300431

RESUMEN

The male reproductive system has a standard immune response regulatory mechanism, However, a variety of external stimuli, including viruses, bacteria, heat, and medications can damage the testicles and cause orchitis and epididymitis. It has been shown that various RNA viruses are more likely to infect the testis than DNA viruses, inducing orchitis and impairing testicular function. It was found that local injection of the viral RNA analog poly(I:C) into the testes markedly disrupted the structure of the seminiferous tubules, accompanied by apoptosis and inflammation. Poly(I:C) mainly inhibited the expression of testosterone synthesis-associated proteins, STAR and MGARP, and affected the synthesis and metabolism of amino acids and lipids in the testis. This led to the disruption of the metabolite levels in the testis of mice, thus affecting the normal spermatogenesis process. The present study analyzed the acute inflammatory response of the testis to viral infection using a multi-omics approach. It provides insights into how RNA virus infection impairs testicular function and offers a theoretical basis for future studies on immune homeostasis and responses under stress conditions in male reproduction.

6.
Cancer Lett ; 585: 216660, 2024 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-38266806

RESUMEN

In the treatment of relapsed or refractory multiple myeloma patients, BCMA-directed autologous CAR-T cells have showed excellent anti-tumor activity. However, their widespread application is limited due to the arguably cost and time-consuming. Multiple myeloma cells highly expressed CD47 molecule and interact with the SIRPα ligand on the surface of macrophages, in which evade the clearance of macrophages through the activation of "don't eat me" signal. In this study, a BCMA-directed universal CAR-T cells, BC404-UCART, secreting a CD47-SIRPα blocker was developed using CRISPR/Cas9 gene-editing system. BC404-UCART cells significantly inhibited tumor growth and prolonged the survival of mice in the xenograft model. The anti-tumor activity of BC404-UCART cells was achieved via two mechanisms, on the one hand, the UCAR-T cells directly killed tumor cells, on the other hand, the BC404-UCART cells enhanced the phagocytosis of macrophages by secreting anti-CD47 nanobody hu404-hfc fusion that blocked the "don't eat me" signal between macrophages and tumor cells, which provides a potential strategy for the development of novel "off-the-shelf" cellular immunotherapies for the treatment of multiple myeloma.


Asunto(s)
Mieloma Múltiple , Neoplasias , Humanos , Ratones , Animales , Mieloma Múltiple/tratamiento farmacológico , Mieloma Múltiple/genética , Antígeno de Maduración de Linfocitos B , Antígeno CD47/genética , Receptores Inmunológicos/genética , Linfocitos T , Antígenos de Diferenciación , Neoplasias/patología , Fagocitosis
7.
Theriogenology ; 215: 321-333, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38128225

RESUMEN

The transcription factor promyelocytic leukemia zinc finger (PLZF, also known as ZBTB16) is critical for the self-renewal of spermatogonial stem cells (SSCs). However, the function of PLZF in SSCs is not clear. Here, we found that PLZF acted as an epigenetic regulator of stem cell maintenance and self-renewal of germ cells. The PLZF protein interacts with the ten-eleven translocation 1 (TET1) protein and subsequently acts as a modulator to regulate the expression of self-renewal-related genes. Furthermore, Transcription Factor 7-like 2 (TCF7L2) is promoted by the coordination of PLZF and Tri-methylation of lysine 4 on histone H3 (H3K4me3). In addition, testicular single-cell sequencing indicated that TCF7L2 is commonly expressed in the PLZF cluster. We demonstrated that PLZF directly targets TCF7L2 and alters the landscape of histone methylation in the SSCs nucleus. Meanwhile, the RD domain and Zn finger domain of PLZF synergize with H3K4me3 and directly upregulate TCF7L2 expression at the transcriptional level. Additionally, we identified a new association between PLZF and the histone methyltransferase EZH2 at the genomic level. Our study identified a new association between PLZF and H3K4me3, established the novel PLZF&TET1-H3K4me3-TCF7L2 axis at the genomic level which regulates undifferentiated spermatogonia, and provided a platform for studying germ cell development in male domestic animals.


Asunto(s)
Factores de Transcripción de Tipo Kruppel , Espermatogonias , Masculino , Animales , Espermatogonias/metabolismo , Proteína de la Leucemia Promielocítica con Dedos de Zinc/genética , Proteína de la Leucemia Promielocítica con Dedos de Zinc/metabolismo , Factores de Transcripción de Tipo Kruppel/genética , Testículo/metabolismo , Factores de Transcripción/metabolismo
8.
Sheng Wu Gong Cheng Xue Bao ; 39(12): 4901-4914, 2023 Dec 25.
Artículo en Chino | MEDLINE | ID: mdl-38147990

RESUMEN

With the rapid development of gene editing technology, the study of spermatogonial stem cells (SSCs) holds great significance in understanding spermatogenesis and its regulatory mechanism, developing transgenic animals, gene therapy, infertility treatment and protecting rare species. Biogenesis of lysosome-related organelles complex 1 subunit 1 (BLOC1S1) is believed to have anti-brucella potential. Exploring the impack of BLOC1S1 on goat SSCs not only helps investigate the ability of BLOC1S1 to promote SSCs proliferation, but also provides a cytological basis for disease-resistant breeding research. In this study, a BLOC1S1 overexpression vector was constructed by homologous recombination. The BLOC1S1 overexpression cell line of goat spermatogonial stem cells was successfully constructed by lentivirus packaging, transfection and puromycin screening. The overexpression efficiency of BLOC1S1 was found to be 18 times higher using real time quantitative PCR (RT-qPCR). Furthermore, the results from cell growth curve analysis, flow cytometry for cell cycle detection, and 5-ethynyl-2'-deoxyuridine (EdU) staining showed that BLOC1S1 significantly increased the proliferation activity of goat SSCs. The results of RT-qPCR, immunofluorescence staining and Western blotting analyses revealed up-regulation of proliferation-related genes (PCNA, CDK2, CCND1), and EIF2S3Y, a key gene regulating the proliferation of spermatogonial stem cells. These findings strongly suggest that the proliferative ability of goat SSCs can be enhanced through the EIF2S3Y/ERK pathway. In summary, this study successfully created a goat spermatogonial stem cell BLOC1S1 overexpression cell line, which exhibited improved proliferation ability. This research laid the groundwork for exploring the regulatory role of BLOC1S1 in goat spermatogonia and provided a cell platform for further study into the biological function of BLOC1S1. These findings also establish a foundation for breeding BLOC1S1 overexpressing goats.


Asunto(s)
Cabras , Células Madre , Animales , Masculino , Espermatogonias/metabolismo , Proliferación Celular , Citometría de Flujo , Testículo/metabolismo
9.
FASEB J ; 37(12): e23306, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37934018

RESUMEN

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.


Asunto(s)
Cabras , Espermatogonias , Animales , Masculino , Ratones , Homeostasis , Inflamación/metabolismo , Espermatogénesis/fisiología , Espermatogonias/metabolismo , Células Madre , Testículo/metabolismo
10.
Angew Chem Int Ed Engl ; 62(42): e202310794, 2023 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-37596246

RESUMEN

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.

11.
Theriogenology ; 211: 65-75, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37586163

RESUMEN

Eif2s3y (eukaryotic translation initiation factor 2, subunit 3, structural gene Y-linked, Eif2s3y) is an essential gene for spermatogenesis. Early studies have shown that Eif2s3y can promote the proliferation of spermatogonial stem cells (SSCs) and can replace the Y chromosome together with sex-determining region Y (Sry) to transform SSCs into round spermatozoa. We injected lentiviral particles into the seminiferous tubules of mouse testes by sterile surgery surgically to establish overexpressing Eif2s3y testes. And then the mice were intraperitoneally injected with LPS to established the model of testis inflammation. Through RNA sequencing, qRT-PCR analysis, Western blot, co-culture etc., we found that Eif2s3y alleviated LPS-induced damage in mouse testes and maintained spermatogenesis. In testes with Eif2s3y overexpression, the seminiferous tubules were more regularly organized after exposure to LPS compared with the control. Eif2s3y performs its function by negatively regulating Adamts5 (a disintegrin and metalloproteinase containing a thrombospondin-1 motif), an extracellular matrix-degrading enzyme. ADAMTS5 shows a disruptive effect when the testis is exposed to LPS. Overexpression of Eif2s3y inhibited the TLR4/NFκB signaling pathway in the testis in response to LPS. Generally, our research shows that Eif2s3y protects the testis from LPS and maintains spermatogenesis by negatively regulating Adamts5.


Asunto(s)
Lipopolisacáridos , Testículo , Masculino , Ratones , Animales , Testículo/metabolismo , Lipopolisacáridos/toxicidad , Espermatogénesis/fisiología , Espermatozoides/metabolismo , Túbulos Seminíferos , Espermatogonias , Proteína ADAMTS5 , Factores de Transcripción/metabolismo
12.
Nat Prod Res ; : 1-5, 2023 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-37470449

RESUMEN

This study aimed to investigate the hypoglycaemic and hypolipidemic activities of total flavonoids from Nymphaea candida (NCTF). The result showed that NCTF could significantly ameliorate various indicators such as FBG, OGTT, TC, TG, LDL-C, and HDL-C in ALX-induced diabetic mice compared with the model group. Meanwhile, in the therapeutical effect study of NCTF on high-fat and high-sugar diets combined with STZ-induced T2DM mice, all parameters including RBG, INS, and INSR related to diabetes were significantly improved by NCTF as well as the serum ALT, AST, ALP, CR, MDA, and IL-6 activities. NCTF could significantly increase the expression levels of SOD and PPAR-γ in T2DM. Pathological observation showed that NCTF could improve the damage to pancreatic and liver tissues in T2DM mice. In conclusion, NCTF has better hypoglycaemic and hypolipidemic effects, and its mechanism may be related to its antioxidant, PPAR-γ regulation, and inhibiting inflammatory cytokine expression.

13.
Angew Chem Int Ed Engl ; 62(36): e202308523, 2023 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-37370248

RESUMEN

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.

14.
J Opt Soc Am A Opt Image Sci Vis ; 40(3): 637-644, 2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-37133048

RESUMEN

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.

15.
Zool Res ; 44(3): 505-521, 2023 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-37070575

RESUMEN

Bacterial or viral infections, such as Brucella, mumps virus, herpes simplex virus, and Zika virus, destroy immune homeostasis of the testes, leading to spermatogenesis disorder and infertility. Of note, recent research shows that SARS-CoV-2 can infect male gonads and destroy Sertoli and Leydig cells, leading to male reproductive dysfunction. Due to the many side effects associated with antibiotic therapy, finding alternative treatments for inflammatory injury remains critical. Here, we found that Dmrt1 plays an important role in regulating testicular immune homeostasis. Knockdown of Dmrt1 in male mice inhibited spermatogenesis with a broad inflammatory response in seminiferous tubules and led to the loss of spermatogenic epithelial cells. Chromatin immunoprecipitation sequencing (ChIP-seq) and RNA sequencing (RNA-seq) revealed that Dmrt1 positively regulated the expression of Spry1, an inhibitory protein of the receptor tyrosine kinase (RTK) signaling pathway. Furthermore, immunoprecipitation-mass spectrometry (IP-MS) and co-immunoprecipitation (Co-IP) analysis indicated that SPRY1 binds to nuclear factor kappa B1 (NF-κB1) to prevent nuclear translocation of p65, inhibit activation of NF-κB signaling, prevent excessive inflammatory reaction in the testis, and protect the integrity of the blood-testis barrier. In view of this newly identified Dmrt1- Spry1-NF-κB axis mechanism in the regulation of testicular immune homeostasis, our study opens new avenues for the prevention and treatment of male reproductive diseases in humans and livestock.


Asunto(s)
Fertilidad , Homeostasis , FN-kappa B , Testículo , FN-kappa B/metabolismo , Fertilidad/genética , Fertilidad/inmunología , Humanos , Masculino , Testículo/inmunología , Testículo/metabolismo , Homeostasis/inmunología , Animales , Ratones , Células HEK293 , Espermatogénesis , Inflamación , Regiones Promotoras Genéticas/genética , Activación Transcripcional , Técnicas de Silenciamiento del Gen
16.
J Am Chem Soc ; 2023 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-37018048

RESUMEN

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.

17.
Acta Pharm Sin B ; 13(3): 1318-1325, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36970210

RESUMEN

Dihydrofolate reductase (DHFR), a housekeeping enzyme in primary metabolism, has been extensively studied as a model of acid-base catalysis and a clinic drug target. Herein, we investigated the enzymology of a DHFR-like protein SacH in safracin (SAC) biosynthesis, which reductively inactivates hemiaminal pharmacophore-containing biosynthetic intermediates and antibiotics for self-resistance. Furthermore, based on the crystal structure of SacH-NADPH-SAC-A ternary complexes and mutagenesis, we proposed a catalytic mechanism that is distinct from the previously characterized short-chain dehydrogenases/reductases-mediated inactivation of hemiaminal pharmacophore. These findings expand the functions of DHFR family proteins, reveal that the common reaction can be catalyzed by distinct family of enzymes, and imply the possibility for the discovery of novel antibiotics with hemiaminal pharmacophore.

18.
Curr Oncol ; 30(1): 938-948, 2023 01 09.
Artículo en Inglés | MEDLINE | ID: mdl-36661720

RESUMEN

BACKGROUND: Liver cancer has caused a heavy burden worldwide. This study aimed to estimate the trends in the mortality and years of life lost (YLL) due to liver cancer and decompose the total deaths into three contributors: population growth, population aging, and mortality change. METHODS: Our study used data from the cause-of-death surveillance system in Wuhan. The mortality and YLL rates were standardized according to the sixth national population census in China. This study calculated the estimated annual percentage change (EAPC) to estimate the trends in the age-standardized mortality rate (ASMR) and age-standardized YLL rate (ASYR). Meanwhile, a decomposition analysis was used to explore the effect of population growth, population aging, and age-specific mortality change on the change in liver cancer deaths. RESULTS: The ASMR of liver cancer declined at an annual rate of 4.6% from 30.87 per 100,000 people in 2010 to 20.29 per 100,000 people in 2019, while the ASYR was at an annual rate of 5.6% from 969.35 per 100,000 people in 2010 to 581.82 per 100,000 people in 2019. Similar downward trends were seen in men and women. The decomposition analysis found that total deaths number changed by -12.42% from 2010 to 2019, of which population growth and population aging caused the total death numbers to increase by 9.75% and 21.15%, while the age-specific mortality change caused the total death numbers to decrease by 43.32%. CONCLUSION: Although the ASMR of liver cancer has declined in recent years in Wuhan, it still causes a heavy burden with the increasing population and rapid population aging and remains an essential public health issue. The government should take measures to reduce the burden of liver cancer, especially among men.


Asunto(s)
Neoplasias Hepáticas , Masculino , Humanos , Femenino , China/epidemiología
19.
ACS Chem Biol ; 18(1): 18-24, 2023 01 20.
Artículo en Inglés | MEDLINE | ID: mdl-36603145

RESUMEN

The recruitment of trans-acting enzymes by nonribosomal peptide synthetase (NRPS) assembly line is rarely reported. ColB1 is a flavin-dependent dehydrogenase that is recruited by an NRPS terminal condensation domain (Ct domain) and catalyzes peptidyl carrier protein (PCP)-tethered cysteine dehydrogenation in collismycin biosynthesis. We here report the crystal structure of ColB1 complexed with FAD and reveal a typical structural fold of acyl-CoA dehydrogenases (ACADs). However, ColB1 shows distinct structural features from ACADs in substrate recognition both at the entrance of and inside the active site. Site-directed mutagenesis and substrate modeling establish a Glu393-mediated catalytic mechanism, by which the cysteine substrate is sandwiched between Glu393 and FAD to facilitate Cα proton abstraction and Cß hydride migration. A ColB1-PCP-Ct complex model is generated, providing structural basis for the unique recruitment interactions between ColB1 and the associated NRPS. These results add insights into the mechanisms by which trans-acting enzymes function in an assembly line.


Asunto(s)
2,2'-Dipiridil , Cisteína , Cisteína/metabolismo , Flavoproteínas/metabolismo , Mutagénesis Sitio-Dirigida , Dominio Catalítico , Péptido Sintasas/metabolismo
20.
Macromol Rapid Commun ; 44(11): e2200778, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36404104

RESUMEN

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.


Asunto(s)
Flúor , Estructuras Metalorgánicas , Halógenos , Polímeros
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