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1.
Reprod Biol ; 24(2): 100891, 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38733656

RESUMEN

Azoospermia constitutes a significant factor in male infertility, defined by the absence of spermatozoa in the ejaculate, afflicting 15% of infertile men. However, a subset of azoospermic cases remains unattributed to known genetic variants. Prior investigations have identified the chibby family member 2 (CBY2) as prominently and specifically expressed in the testes of both humans and mice, implicating its potential involvement in spermatogenesis. In this study, we conducted whole exome sequencing (WES) on an infertile family to uncover novel genetic factors contributing to azoospermia. Our analysis revealed a homozygous c .355 C>A variant of CBY2 in a non-obstructive azoospermic patient. This deleterious variant significantly diminished the protein expression of CBY2 both in vivo and in vitro, leading to a pronounced disruption of spermatogenesis at the early round spermatid stage post-meiosis. This disruption was characterized by a nearly complete loss of elongating and elongated spermatids. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) and co-immunoprecipitation assays demonstrated the interaction between CBY2 and Piwi-like protein 1 (PIWIL1). Immunofluorescence staining further confirmed the co-localization of CBY2 and PIWIL1 in the testes during the spermatogenic process in both humans and mice. Additionally, diminished PIWIL1 expression was observed in the testicular tissue from the affected patient. Our findings suggest that the homozygous c .355 C>A variant of CBY2 compromises CBY2 function, contributing to defective spermatogenesis at the round spermiogenic stage and implicating its role in the pathogenesis of azoospermia.

2.
Sci Rep ; 14(1): 10471, 2024 05 07.
Artículo en Inglés | MEDLINE | ID: mdl-38714840

RESUMEN

Lung diseases globally impose a significant pathological burden and mortality rate, particularly the differential diagnosis between adenocarcinoma, squamous cell carcinoma, and small cell lung carcinoma, which is paramount in determining optimal treatment strategies and improving clinical prognoses. Faced with the challenge of improving diagnostic precision and stability, this study has developed an innovative deep learning-based model. This model employs a Feature Pyramid Network (FPN) and Squeeze-and-Excitation (SE) modules combined with a Residual Network (ResNet18), to enhance the processing capabilities for complex images and conduct multi-scale analysis of each channel's importance in classifying lung cancer. Moreover, the performance of the model is further enhanced by employing knowledge distillation from larger teacher models to more compact student models. Subjected to rigorous five-fold cross-validation, our model outperforms existing models on all performance metrics, exhibiting exceptional diagnostic accuracy. Ablation studies on various model components have verified that each addition effectively improves model performance, achieving an average accuracy of 98.84% and a Matthews Correlation Coefficient (MCC) of 98.83%. Collectively, the results indicate that our model significantly improves the accuracy of disease diagnosis, providing physicians with more precise clinical decision-making support.


Asunto(s)
Aprendizaje Profundo , Neoplasias Pulmonares , Redes Neurales de la Computación , Humanos , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/clasificación , Carcinoma Pulmonar de Células Pequeñas/diagnóstico , Carcinoma Pulmonar de Células Pequeñas/patología , Carcinoma Pulmonar de Células Pequeñas/clasificación , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/patología , Adenocarcinoma/patología , Adenocarcinoma/diagnóstico , Adenocarcinoma/clasificación , Procesamiento de Imagen Asistido por Computador/métodos , Diagnóstico Diferencial
3.
J Cardiothorac Surg ; 19(1): 278, 2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38711077

RESUMEN

OBJECTIVE: To evaluate the efficacy and safety of intrapleural perfusion with hyperthermic chemotherapy (IPHC) in treating malignant pleural effusion (MPE). METHODS: PubMed, Embase, Cochrane Library, Chinese National Knowledge Infrastructure (CNKI), Chinese Biomedical Literature Database (CBM), VIP Chinese Science and Technology Journal Full-text Database (VP-CSJFD), and Wanfang database were searched by computer from database establishment to January 17, 2024. Relevant randomized controlled articles with IPHC as the observational group and intrapleural perfusion chemotherapy (IPC) as the control group for MPE were included. Then, the methodological quality of the included articles was evaluated and statistically analyzed using Stata 16.0. RESULTS: Sixteen trials with 647 patients receiving IPHC and 661 patients receiving IPC were included. The meta-analysis found that MPE patients in the IPHC group had a more significant objective response rate [RR = 1.31, 95%CI (1.23, 1.38), P < 0.05] and life quality improvement rate [RR = 2.88, 95%CI (1.95, 4.24), P < 0.05] than those in the IPC group. IPHC and IPC for MPE patients had similar incidence rates of asthenia, thrombocytopenia, hepatic impairment, and leukopenia. CONCLUSION: Compared with IPC, IPHC has a higher objective response rate without significantly increasing adverse reactions. Therefore, IPHC is effective and safe. However, this study is limited by the quality of the literature. Therefore, more high-quality, multi-center, large-sample, rigorously designed randomized controlled clinical studies are still needed for verification and evaluation.


Asunto(s)
Hipertermia Inducida , Derrame Pleural Maligno , Humanos , Derrame Pleural Maligno/terapia , Hipertermia Inducida/métodos , Resultado del Tratamiento , Quimioterapia del Cáncer por Perfusión Regional/métodos , Quimioterapia del Cáncer por Perfusión Regional/efectos adversos , Antineoplásicos/administración & dosificación , Antineoplásicos/efectos adversos
4.
Genome Res ; 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38744529

RESUMEN

While DNA N6-adenine methylation (6mA) is best known in prokaryotes, its presence in eukaryotes has generated great interest recently. Biochemical and genetic evidence supports that AMT1, a MT-A70 family methyltransferase (MTase), is crucial for 6mA deposition in unicellular eukaryotes. Nonetheless, 6mA transmission mechanism remains to be elucidated. Taking advantage of Single Molecule Real-Time Circular Consensus Sequencing (SMRT CCS), here we provide definitive evidence for semiconservative transmission of 6mA in Tetrahymena thermophila In wild-type (WT) cells, 6mA occurs at the self-complementary ApT dinucleotide, mostly in full methylation (full-6mApT); after DNA replication, hemi-methylation (hemi-6mApT) is transiently present on the parental strand, opposite to the daughter strand readily labeled by 5-bromo-2'-deoxyuridine (BrdU). In ΔAMT1 cells, 6mA predominantly occurs as hemi-6mApT. Hemi-to-full conversion in WT cells is fast, robust, and processive, while de novo methylation in ΔAMT1 cells is slow and sporadic. In Tetrahymena, regularly spaced 6mA clusters coincide with linker DNA of nucleosomes arrayed in the gene body. Importantly, in vitro methylation of human chromatin by reconstituted AMT1 complex recapitulates preferential targeting of hemi-6mApT sites in linker DNA, supporting AMT1's intrinsic and autonomous role in maintenance methylation. We conclude that 6mA is transmitted by a semiconservative mechanism: full-6mApT is split by DNA replication into hemi-6mApT, which is restored to full-6mApT by AMT1-dependent maintenance methylation. Our study dissects AMT1-dependent maintenance methylation and AMT1-independent de novo methylation, reveals a 6mA transmission pathway with striking similarity to 5-methyl cytosine (5mC) transmission at the CpG dinucleotide, and establishes 6mA as a bona fide eukaryotic epigenetic mark.

5.
Sci Total Environ ; 931: 172866, 2024 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-38705291

RESUMEN

Tetracycline antibiotics (TCs) are extensively used in clinical medicine, animal husbandry, and aquaculture because of their cost-effectiveness and high antibacterial efficacy. However, the presence of TCs residues in the environment poses risks to humans. In this study, an inner filter effect (IFE) fluorescent probe, 2,2'-(ethane-1,2-diylbis((2-((2-methylquinolin-8-yl)amino)-2-oxoethyl)azanediyl))diacetic acid (MQDA), was developed for the rapid detection of Eu3+ within 30 s. And its complex [MQDA-Eu3+] was successfully used for the detection of TCs. Upon coordination of a carboxyl of MQDA with Eu3+ to form a [MQDA-Eu3+] complex, the carboxyl served as an antenna ligand for the effective detection of Eu3+ to intensify the emission intensity of MQDA via "antenna effect", the process was the energy absorbed by TCs via UV excitation was effectively transferred to Eu3+. Fluorescence quenching of the [MQDA-Eu3+] complex was caused by the IFE in multicolor fluorescence systems. The limits of detection of [MQDA-Eu3+] for oxytetracycline, chlorotetracycline hydrochloride, and tetracycline were 0.80, 0.93, and 1.7 µM in DMSO/HEPES (7:3, v/v, pH = 7.0), respectively. [MQDA-Eu3+] demonstrated sensitive detection of TCs in environmental and food samples with satisfactory recoveries and exhibited excellent imaging capabilities for TCs in living cells and zebrafish with low cytotoxicity. The proposed approach demonstrated considerable potential for the quantitative detection of TCs.

6.
Bioresour Technol ; 402: 130797, 2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38705214

RESUMEN

High-solid anaerobic digestion of hydrothermal sewage sludge has been developed. In order to upgrade the process by focusing on ammonia inhibition, a simply-equipped stripping system without additional alkali or heat supply was introduced by in situ biogas self-circulation. As the determined limit of total ammonia nitrogen at 1500 mg/L and 1000 mg/L for the mesophilic (MAD) and thermophilic anaerobic digestion (TAD) respectively and stripping rate at 5 L/min, continuous MAD and TAD was conducted in parallel. The stripping system successfully polished up the ammonia inhibition, and methanogenic capability of the TAD was promoted to approximately 90.0 % of the potential. Intermittent stripping mode proved usable. More frequent stripping was inevitable for the TAD as compared to the MAD. Hydraulic retention time below 20 d resulted in failure of the stripping mode due to rapid ammonia generation. Overall, this technology was practical in upgrading high-solid sludge digestion by effective ammonia control.

7.
J Agric Food Chem ; 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38714361

RESUMEN

4-Hydroxyphenylpyruvate dioxygenase (HPPD) is a crucial target enzyme in albino herbicides. The inhibition of HPPD activity interferes with the synthesis of carotenoids, blocking photosynthesis and resulting in bleaching and necrosis. To develop herbicides with excellent activity, a series of 3-hydroxy-2-(6-substituted phenoxynicotinoyl)-2-cyclohexen-1-one derivatives were designed via active substructure combination. The title compounds were characterized via infrared spectroscopy, 1H and 13C nuclear magnetic resonance spectroscopies, and high-resolution mass spectrometry. The structure of compound III-17 was confirmed via single-crystal X-ray diffraction. Preliminary tests demonstrated that some compounds had good herbicidal activity. Crop safety tests revealed that compound III-29 was safer than the commercial herbicide mesotrione in wheat and peanuts. Moreover, the compound exhibited the highest inhibitory activity against Arabidopsis thaliana HPPD (AtHPPD), with a half-maximal inhibitory concentration of 0.19 µM, demonstrating superior activity compared with mesotrione (0.28 µM) in vitro. A three-dimensional quantitative structure-activity relationship study revealed that the introduction of smaller groups to the 5-position of cyclohexanedione and negative charges to the 3-position of the benzene ring enhanced the herbicidal activity. A molecular structure comparison demonstrated that compound III-29 was beneficial to plant absorption and conduction. Molecular docking and molecular dynamics simulations further verified the stability of the complex formed by compound III-29 and AtHPPD. Thus, this study may provide insights into the development of green and efficient herbicides.

8.
Neuropsychiatr Dis Treat ; 20: 885-896, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38645710

RESUMEN

Background: The global incidence of acute events in psychiatric patients is intensifying, and models to successfully predict acute events have attracted much attention. Objective: To explore the influence factors of acute incident severe mental disorders (SMDs) and the application of Rstudio statistical software, and build and verify a nomogram prediction model. Methods: SMDs were taken as research objects. The questionnaire survey method was adopted to collect data. Patients with acute event independent factors were screened. R software multivariable Logistic regression model was constructed and a nomogram was drawn. Results: A total of 342 patients with SMDs were hospitalized, and the number of patients who encountered acute events was 64, which accounted for 18.70% of all patients. Statistical significances were found in many aspects (all P ˂ 0.05). Such aspects included Medication adherence, disease diagnosis, marital status, caregivers, social support and the hospitalization environment (odds ratio (OR) = 4.08, 11.62, 12.06, 10.52, 0.04 and 0.61, respectively) were independent risk factors for the acute events of patients with SMDs. The prediction model was modeled, and the AUC was 0.77 and 0.80. The calibration curve shows that the model has good calibration. The clinical decision curve shows that the model has a good clinical effect. Conclusion: The constructed risk prediction model shows good prediction effectiveness in the acute events of patients with SMDs, which is helpful for the early detection of clinical mental health staff at high risk of acute events.

9.
Bioorg Chem ; 147: 107339, 2024 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-38643566

RESUMEN

Stroke poses a serious risk to the physical and mental health of patients. Endogenous compounds are widely used to treat ischemic stroke. Lipoic acid, a naturally occurring (R)-5-(1,2-dithiolan-3-yl)pentanoic acid, has therapeutic potential for the treatment of ischemic stroke. However, the direct application of lipoic acid is limited by its relatively low efficacy and instability. Therefore, there is a need to modify the structure of lipoic acid to improve its pharmaceutical capabilities. Currently, 37 lipoic acid derivatives have been synthesized, and compound AA-9 demonstrated optimal therapeutic potential in an in vitro model of induced oxidative damage using tert-butyl hydroperoxide (t-BHP). In addition, in vitro experiments have shown that compound AA-9 has an excellent safety profile. Subsequently, the therapeutic effect of AA-9 was significant in the rat MCAO ischemic stroke model, which may be attributed to the antioxidant and anti-inflammatory effects of compound AA-9 by activating PGC-1α and inhibiting NLRP3. Notably, compound AA-9 exhibited higher stability and better bioavailability properties than ALA in plasma stability and pharmacokinetic properties. In conclusion, AA-9 may be a promising neuroprotective agent for the treatment of ischemic stroke and warrants further investigation.

10.
Artículo en Inglés | MEDLINE | ID: mdl-38661035

RESUMEN

Treponema pallidum, the causative agent of syphilis, is a sexually transmitted microorganism that exhibits remarkable motility capabilities, allowing it to affect various systems. Despite its structural resemblance to gram-negative bacteria due to its dual-membrane, T. pallidum possesses a lower abundance of outer membrane proteins (OMPs), which enables it to effectively conceal itself. This review presents a comprehensive analysis of the clinical diagnostic potential associated with the OMPs of T. pallidum. Furthermore, the known OMPs in T. pallidum that are responsible for mediating host interactions have been progressively elucidated. This review aims to shed light on the pathogenesis of syphilis, encompassing aspects such as vascular inflammation, chancre self-healing, neuroinvasion, and reinfection. Additionally, this review offers a detailed overview of the current state and prospects of development in the field of syphilis vaccines, with the ultimate goal of establishing a foundation for understanding the pathogenesis and implementing effective prevention strategies against syphilis.

11.
Cell Mol Life Sci ; 81(1): 170, 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38597976

RESUMEN

In our prior investigation, we discerned loss-of-function variants within the gene encoding glutamine-rich protein 2 (QRICH2) in two consanguineous families, leading to various morphological abnormalities in sperm flagella and male infertility. The Qrich2 knockout (KO) in mice also exhibits multiple morphological abnormalities of the flagella (MMAF) phenotype with a significantly decreased sperm motility. However, how ORICH2 regulates the formation of sperm flagella remains unclear. Abnormal glutamylation levels of tubulin cause dysplastic microtubules and flagella, eventually resulting in the decline of sperm motility and male infertility. In the current study, by further analyzing the Qrich2 KO mouse sperm, we found a reduced glutamylation level and instability of tubulin in Qrich2 KO mouse sperm flagella. In addition, we found that the amino acid metabolism was dysregulated in both testes and sperm, leading to the accumulated glutamine (Gln) and reduced glutamate (Glu) concentrations, and disorderly expressed genes responsible for Gln/Glu metabolism. Interestingly, mice fed with diets devoid of Gln/Glu phenocopied the Qrich2 KO mice. Furthermore, we identified several mitochondrial marker proteins that could not be correctly localized in sperm flagella, which might be responsible for the reduced mitochondrial function contributing to the reduced sperm motility in Qrich2 KO mice. Our study reveals a crucial role of a normal Gln/Glu metabolism in maintaining the structural stability of the microtubules in sperm flagella by regulating the glutamylation levels of the tubulin and identifies Qrich2 as a possible novel Gln sensor that regulates microtubule glutamylation and mitochondrial function in mouse sperm.


Asunto(s)
Glutamina , Infertilidad Masculina , Animales , Humanos , Masculino , Ratones , Ácido Glutámico , Infertilidad Masculina/genética , Ratones Noqueados , Microtúbulos , Mitocondrias , Proteínas Mitocondriales , Semen , Motilidad Espermática , Espermatozoides , Tubulina (Proteína)
12.
J Ovarian Res ; 17(1): 78, 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38600539

RESUMEN

BACKGROUND: This study investigated the association between Anti-Müllerian Hormone (AMH) and relevant metabolic parameters and assessed its predictive value in the clinical diagnosis of polycystic ovarian syndrome (PCOS). METHODS: A total of 421 women aged 20-37 years were allocated to the PCOS (n = 168) and control (n = 253) groups, and their metabolic and hormonal parameters were compared. Spearman correlation analysis was conducted to investigate associations, binary logistic regression was used to determine PCOS risk factors, and receiver operating characteristic (ROC) curves were generated to evaluate the predictive value of AMH in diagnosing PCOS. RESULTS: The PCOS group demonstrated significantly higher blood lipid, luteinizing hormone (LH), and AMH levels than the control group. Glucose and lipid metabolism and hormonal disorders in the PCOS group were more significant than in the control group among individuals with and without obesity. LH, TSTO, and AMH were identified as independent risk factors for PCOS. AMH along with LH, and antral follicle count demonstrated a high predictive value for diagnosing PCOS. CONCLUSION: AMH exhibited robust diagnostic use for identifying PCOS and could be considered a marker for screening PCOS to improve PCOS diagnostic accuracy. Attention should be paid to the effect of glucose and lipid metabolism on the hormonal and related parameters of PCOS populations.


Asunto(s)
Hormona Antimülleriana , Síndrome del Ovario Poliquístico , Femenino , Humanos , Hormona Antimülleriana/sangre , Glucosa/metabolismo , Hormona Luteinizante/sangre , Síndrome del Ovario Poliquístico/sangre , Síndrome del Ovario Poliquístico/metabolismo , Síndrome del Ovario Poliquístico/patología , Sensibilidad y Especificidad , Adulto
13.
J Med Chem ; 67(8): 6313-6326, 2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38574345

RESUMEN

Coactivator-associated arginine methyltransferase 1 (CARM1), an important member of type I protein arginine methyltransferases (PRMTs), has emerged as a promising therapeutic target for various cancer types. In our previous study, we have identified a series of type I PRMT inhibitors, among which ZL-28-6 (6) exhibited increased activity against CARM1 while displaying decreased potency against other type I PRMTs. In this work, we conducted chemical modifications on compound 6, resulting in a series of (2-(benzyloxy)phenyl)methanamine derivatives as potent inhibitors of CARM1. Among them, compound 17e displayed remarkable potency and selectivity for CARM1 (IC50 = 2 ± 1 nM), along with notable antiproliferative effects against melanoma cell lines. Cellular thermal shift assay and western blot experiments confirmed that compound 6 effectively targets CARM1 within cells. Furthermore, compound 17e displayed good antitumor efficacy in a melanoma xenograft model, indicating that this compound warrants further investigation as a potential anticancer agent.


Asunto(s)
Antineoplásicos , Melanoma , Proteína-Arginina N-Metiltransferasas , Humanos , Proteína-Arginina N-Metiltransferasas/antagonistas & inhibidores , Proteína-Arginina N-Metiltransferasas/metabolismo , Animales , Melanoma/tratamiento farmacológico , Melanoma/patología , Antineoplásicos/farmacología , Antineoplásicos/química , Antineoplásicos/síntesis química , Antineoplásicos/uso terapéutico , Línea Celular Tumoral , Ratones , Relación Estructura-Actividad , Proliferación Celular/efectos de los fármacos , Inhibidores Enzimáticos/farmacología , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/uso terapéutico , Ensayos Antitumor por Modelo de Xenoinjerto , Ratones Desnudos , Ensayos de Selección de Medicamentos Antitumorales
14.
Small ; : e2400561, 2024 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-38639024

RESUMEN

Thermochemical water-splitting cycles are technically feasible for hydrogen production from water. However, the ultrahigh operation temperature and low efficiency seriously restrict their practical application. Herein, one-step and one-pot thermocatalytic water-splitting process is reported at water boiling condition catalyzed by single atomic Pt on defective In2O3. Water splitting into hydrogen is verified by D2O isotopic experiment, with an optimized hydrogen production rate of 36.4 mmol·h-1·g-1 as calculated on Pt active sites. It is revealed that three-centered Pt1In2 surrounding oxygen vacancy as catalytic ensembles promote the dissociation of the adsorbed water into H, which transfers to singlet atomic Pt sites for H2 production. Remaining OH groups on adjacent In sites from Pt1In2 ensembles undergoes O─O bonding, hyperoxide formation and diminishing via triethylamine oxidation, water re-adsorption for completing the catalytic cycle. Current work represents an isothermal and continuous thermocatalytic water splitting under mild condition, which can re-awaken the research interest to produce H2 from water using low-grade heat and competes with photocatalytic, electrolytic, and photoelectric reactions.

15.
Coron Artery Dis ; 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38563191

RESUMEN

BACKGROUND: Left ventricular thrombus (LVT) is a severe cardiovascular complication occurring in approximately 10% of patients with acute anterior ST-segment elevation myocardial infarction. This study aimed to evaluate the association between neutrophil-to-lymphocyte ratio (NLR) and in-hospital major adverse cardiovascular and cerebrovascular events (MACCE) in patients with LVT. MATERIAL AND METHODS: This multicenter retrospective study was conducted between January 2000 and June 2022 in hospitalized patients with LVT. The outcome included in-hospital MACCE. The association between NLR and in-hospital MACCE was measured by odds ratios (ORs). The restricted cubic spline model was used for dose-response analysis. RESULTS: A total of 197 LVT patients from four centers were included for analysis in this study. MACCE occurred in 13.7% (27/197) of the patients. After adjusting for estimated glomerular filtration rate (eGFR), D-dimer, and age, the OR for MACCE comparing first to the third tertile of NLR was 13.93 [95% confidence interval: 2.37-81.77, P = 0.004, P-trend = 0.008]. When further adjusting for etiology and heart failure with reduced ejection fraction (HFrEF), the association remained statistically significant. Spline regression models showed an increasing trend in the incidence of MACCEs with NLR both in crude and adjusted models. Subgroup analyses showed that a high NLR may be correlated with poorer outcomes for LVT patients older than 65 years, or with hypertension, dyslipidemia, low ejection fraction, liver, and renal dysfunctions. CONCLUSION: In conclusion, these findings suggested that higher NLR may be associated with an increased risk of in-hospital MACCE in patients with LVT.

16.
Nat Commun ; 15(1): 3531, 2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38670961

RESUMEN

E6AP dysfunction is associated with Angelman syndrome and Autism spectrum disorder. Additionally, the host E6AP is hijacked by the high-risk HPV E6 to aberrantly ubiquitinate the tumor suppressor p53, which is linked with development of multiple types of cancer, including most cervical cancers. Here we show that E6AP and the E6AP/E6 complex exist, respectively, as a monomer and a dimer of the E6AP/E6 protomer. The short α1-helix of E6AP transforms into a longer helical structure when in complex with E6. The extended α1-helices of the dimer intersect symmetrically and contribute to the dimerization. The two protomers sway around the crossed region of the two α1-helices to promote the attachment and detachment of substrates to the catalytic C-lobe of E6AP, thus facilitating ubiquitin transfer. These findings, complemented by mutagenesis analysis, suggest that the α1-helix, through conformational transformations, controls the transition between the inactive monomer and the active dimer of E6AP.


Asunto(s)
Multimerización de Proteína , Ubiquitina-Proteína Ligasas , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitina-Proteína Ligasas/química , Ubiquitina-Proteína Ligasas/genética , Humanos , Ubiquitina/metabolismo , Ubiquitina/química , Ubiquitinación , Modelos Moleculares , Cristalografía por Rayos X , Proteínas Oncogénicas Virales/metabolismo , Proteínas Oncogénicas Virales/química , Proteínas Oncogénicas Virales/genética , Proteína p53 Supresora de Tumor/metabolismo , Proteína p53 Supresora de Tumor/química , Proteína p53 Supresora de Tumor/genética , Unión Proteica , Conformación Proteica en Hélice alfa
17.
J Agric Food Chem ; 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38598318

RESUMEN

Mesosulfuron-methyl, an inhibitor of acetolactate synthase (ALS), has been extensively used in wheats. However, it can damage wheat (Triticum aestivum) and even lead to crop death. Herbicide safeners selectively shield crops from such damage without compromising weed control. To mitigate the phytotoxicity of mesosulfuron-methyl in crops, several purine derivatives were developed based on active substructure splicing. The synthesized title compounds underwent thorough characterization using infrared spectroscopy, 1H nuclear magnetic resonance (1H NMR), 13C nuclear magnetic resonance (13C NMR), and high-resolution mass spectrometry. We evaluated chlorophyll and glutathione contents as well as various enzyme activities to evaluate the safer activity of these compounds. Compounds III-3 and III-7 exhibited superior activity compared with the safener mefenpyr-diethyl. Molecular structure analysis, along with predictions of absorption, distribution, metabolism, excretion, and toxicity, indicated that compound III-7 shared pharmacokinetic traits with the commercial safener mefenpyr-diethyl. Molecular docking simulations revealed that compound III-7 competitively bound to the ALS active site with mesosulfuron-methyl, elucidating the protective mechanism of the safeners. Overall, this study highlights purine derivatives as potential candidates for novel safener development.

18.
Sci Rep ; 14(1): 8132, 2024 04 07.
Artículo en Inglés | MEDLINE | ID: mdl-38584153

RESUMEN

To figure out how does SARS-CoV-2 affect sperm parameters and what influencing factors affect the recovery of sperm quality after infection? We conducted a prospective cohort study and initially included 122 men with SARS-CoV-2 infection. The longest time to track semen quality after infection is 112 days and 58 eligible patients were included in our study eventually. We subsequently exploited a linear mixed-effects model to statistically analyze their semen parameters at different time points before and after SARS-CoV-2 infection. Semen parameters were significantly reduced after SARS-CoV-2 infection, including total sperm count (211 [147; 347] to 167 [65.0; 258], P < 0.001), sperm concentration (69.0 [38.8; 97.0] to 51.0 [25.5; 71.5], P < 0.001), total sperm motility (57.5 [52.3; 65.0] to 51.0 [38.5; 56.8], P < 0.001), progressive motility (50.0 [46.2; 58.0] to 45.0 [31.5; 52.8], P < 0.001). The parameters displayed the greatest diminution within 30 days after SARS-CoV-2 infection, gradually recovered thereafter, and exhibited no significant difference after 90 days compared with prior to COVID-19 infection. In addition, the patients in the group with a low-grade fever showed a declining tendency in semen parameters, but not to a significant degree, whereas those men with a moderate or high fever produced a significant drop in the same parameters. Semen parameters were significantly reduced after SARS-CoV-2 infection, and fever severity during SARS-CoV-2 infection may constitute the main influencing factor in reducing semen parameters in patients after recovery, but the effect is reversible and the semen parameters gradually return to normal with the realization of a new spermatogenic cycle.


Asunto(s)
COVID-19 , Infertilidad Masculina , Humanos , Masculino , Análisis de Semen , Semen , Estudios Prospectivos , Motilidad Espermática , SARS-CoV-2 , Espermatozoides , Recuento de Espermatozoides
19.
Int J Cancer ; 2024 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-38602070

RESUMEN

Early detection is critical for improving pancreatic cancer prognosis. Our study aims to identify circulating microRNAs (miRNAs) associated with pancreatic cancer risk. The two-stage study used plasma samples collected ≤5 years prior to cancer diagnosis, from case-control studies nested in five prospective cohort studies. The discovery stage included 185 case-control pairs from the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial. Replication stage samples comprised 277 pairs from Shanghai Women's Health Study/Shanghai Men's Health Study, Southern Community Cohort Study, and Multiethnic Cohort Study. Seven hundred and ninety-eight miRNAs were measured using the NanoString nCounter Analysis System. Odds ratios (OR) and 95% confidence intervals (CI) for per 10% change in miRNAs in association with pancreatic cancer risk were derived from conditional logistic regression analysis in discovery and replication studies, separately, and then meta-analyzed. Stratified analysis was conducted by age at diagnosis (<65/≥65 years) and time interval between sample collection and diagnosis (≤2/>2 years). In the discovery stage, 120 risk associated miRNAs were identified at p < .05. Three were validated in the replication stage: hsa-miR-199a-3p/hsa-miR-199b-3p, hsa-miR-767-5p, and hsa-miR-191-5p, with respective ORs (95% CI) being 0.89 (0.84-0.95), 1.08 (1.02-1.13), and 0.90 (0.85-0.95). Five additional miRNAs, hsa-miR-640, hsa-miR-874-5p, hsa-miR-1299, hsa-miR-22-3p, and hsa-miR-449b-5p, were validated among patients diagnosed at ≥65 years, with OR (95% CI) of 1.23 (1.09-1.39), 1.33 (1.16-1.52), 1.25 (1.09-1.43), 1.28 (1.12-1.46), 0.76 (0.65-0.89), and 1.22 (1.07-1.39), respectively. The miRNA targets were enriched in pancreatic carcinogenesis/progression-related pathways. Our study suggests that circulating miRNAs may identify individuals at high risk for pancreatic cancer ≤5 years prior to diagnosis, indicating its potential utility in cancer screening and surveillance.

20.
Langmuir ; 40(19): 9911-9925, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38688881

RESUMEN

Groundwater infiltration into tunnels causes water to percolate through the fissure channels in the initial support shotcrete. This results in the dissolution and outflow of calcium hydroxide, a key product of cement hydration. This process significantly incurs the formation of crystallization blockages in the tunnel drainage systems. Optimizing the shotcrete mixing ratio is a feasible way to mitigate these blockages. Therefore, this study conducts calcium dissolution tests to investigate the impact of six admixtures, namely, antialkali agent, nanosilica, nanosilica carbonate, fly ash, sodium methyl silicate waterproofing agents, and silane waterproofing agents, on calcium dissolution resistance. Also, mechanical and microscopic tests are carried out to examine their impact on the strength and pore structure of the shotcrete. The objective of this study is to determine the optimal admixture for enhancing the calcium dissolution resistance of shotcrete. Results indicate that the antialkali agent significantly reduces the calcium leaching content of shotcrete. When the dosage is 14%, the calcium leaching amount is reduced by 68.4% in 28 days. Followed by nanosilica and silane waterproofing agents, with optimal dosages of 12 and 0.4%, respectively, the dissolution amount of calcium ions in shotcrete was reduced by 32.87 and 26.5%, respectively. Fly ash curing for 28 days can also reduce the calcium ion dissolution of shotcrete, while nanocalcium carbonate and sodium methyl silicate have little effect on the calcium dissolution of shotcrete. The antialkali agent with a strong calcium ion dissolution effect can improve the tensile strength of shotcrete under long-term curing conditions, which can be increased by 52%, but it compromises the growth of compressive strength. Nanosilica, fly ash, and silane waterproofing agents can improve both the compressive strength and tensile strength of shotcrete under long-term curing conditions. Specifically, at 28 days of curing, the compressive strength increased by 16.83, 28.8, and 20% and the tensile strength increased by 50.24, 60, and 64.5%. In addition, the microscopy results show that the antialkali agent, nanosilica, and silane waterproofing agents promote the hydration process of cement to form ettringite with a low and stable calcium-silicon ratio and reduce calcium hydroxide crystals. Nanosilica and silane waterproofing agents optimize the pore distribution in shotcrete by increasing beneficial pores, decreasing harmful pores, and reducing total porosity.

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