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1.
Front Pharmacol ; 15: 1405521, 2024.
Article in English | MEDLINE | ID: mdl-39144617

ABSTRACT

Introduction: Almonertinib is an important third-generation epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) exhibiting high selectivity to EGFR-sensitizing and T790M-resistant mutations. Almonertinib resistance is a major obstacle in clinical use. Baicalein possesses antitumor properties, but its mechanism of antitumor action against almonertinib-resistant non-small cell lung cancer (NSCLC) remains unelucidated. Methods: CCK-8 assay was used to examine the survival rate of H1975/AR and HCC827/AR cells following treatment for 24 h with different concentrations of baicalein, almonertinib or their combination. The changes in colony formation ability, apoptosis, and intracellular reactive oxygen species (ROS) levels of the treated cells were analyzed using colony formation assay and flow cytometry. Western blotting was performed to detect the changes in protein expressions in the cells. The effects of pre-treatment with NAC on proliferation, apoptosis, and PI3K/Akt signaling pathway were observed in baicalein- and/or almonertinib-treated cells. A nude mouse model bearing subcutaneous HCC827/AR cell xenograft were treated with baicalein (20 mg/kg) or almonertinib (15 mg/kg), and the tumor volume and body mass changes was measured. Results: Both baicalein and almonertinib represses the viability of HCC827/AR and H1975/AR cells in a concentration-dependent manner. Compared with baicalein or almonertinib alone, the combined application of the two drugs dramatically attenuates cell proliferation; triggers apoptosis; causes cleavage of Caspase-3, PARP, and Caspase-9; downregulates the protein expressions of p-PI3K and p-Akt; and significantly inhibits tumor growth in nude mice. Furthermore, baicalein combined with almonertinib results in massive accumulation of reactive oxygen species (ROS) and preincubation with N-acetyl-L-cysteine (ROS remover) prevents proliferation as well as inhibits apoptosis induction, with partial recovery of the decline of p-PI3K and p-Akt. Discussion: The combination of baicalein and almonertinib can improve the antitumor activity in almonertinib-resistant NSCLC through the ROS-mediated PI3K/Akt pathway.

2.
Food Res Int ; 192: 114778, 2024 Sep.
Article in English | MEDLINE | ID: mdl-39147466

ABSTRACT

Fermentation can transform bioactive compounds in food and improve their biological activity. This study aims to explore the transformation of polyphenols in mulberry juice and the improvement of its anti-aging effect. The results demonstrated that Lactobacillus plantarum SC-5 transformed anthocyanin in mulberry juice into more phenolic acids, especially improved 2-hydroxy-3-(4-hydroxyphenyl) propanoic acid from 4.16 ± 0.06 to 10.07 ± 0.03. In the D-gal-induced mouse model, fermented mulberry juice significantly raised the abundance of Bifidobacteriaceae (303.7 %) and Lactobacillaceae (237.2 %) and Short-chain fatty acids (SCFAs) in intestine, further reducing the level of oxidative stress (12.3 %). Meanwhile, the expression of Sirtuin 1 (SIRT1) and Brain-derived neurotrophic factor (BDNF) increased, which protected the integrity of hippocampal tissue. Morris water maze results approved that fermented mulberry juice improved cognitive ability in aging mice (30.3 %). This study provides theoretical support for the view that fermentation is an effective means of developing functional foods.


Subject(s)
Fermentation , Hydroxybenzoates , Lactobacillus plantarum , Morus , Polyphenols , Animals , Morus/chemistry , Polyphenols/pharmacology , Lactobacillus plantarum/metabolism , Hydroxybenzoates/pharmacology , Mice , Male , Fruit and Vegetable Juices , Aging/drug effects , Brain-Derived Neurotrophic Factor/metabolism , Gastrointestinal Microbiome/drug effects , Anthocyanins/pharmacology , Oxidative Stress/drug effects , Fatty Acids, Volatile/metabolism , Sirtuin 1
3.
Curr Opin Genet Dev ; 88: 102243, 2024 Aug 13.
Article in English | MEDLINE | ID: mdl-39142048

ABSTRACT

Our knowledge of human biology is mainly originated from studies using animal models. However, interspecies differences between human and model organisms may lead to imprecise extrapolation of results obtained from model organisms. Organoids are three-dimensional cell clusters derived from pluripotent or adult stem cells that self-organize into organ-like structures reminiscent of the cognate organ. The establishment of human organoids makes it possible to study organ or tissue pathophysiology that is specific to human beings. However, most organoids do not have organ-specific vasculature, neurons, and immune cells, hence limiting their utility in emulating complex pathophysiological phenotypes. Among the various approaches to address these limitations, xenotransplantation represents a promising 'shortcut'. We will discuss recent advance in constructing tissue complexity in organoids, with a special focus on xenotransplantation.

4.
World J Pediatr ; 2024 Aug 14.
Article in English | MEDLINE | ID: mdl-39143259

ABSTRACT

BACKGROUND: Mycoplasma pneumoniae (M. pneumoniae) is a significant contributor to community-acquired pneumonia among children. Since 1968, when a strain of M. pneumoniae resistant to macrolide antibiotics was initially reported in Japan, macrolide-resistant M. pneumoniae (MRMP) has been documented in many countries worldwide, with varying incidence rates. MRMP infections lead to a poor response to macrolide antibiotics, frequently resulting in prolonged fever, extended antibiotic treatment, increased hospitalization, intensive care unit admissions, and a significantly higher proportion of patients receiving glucocorticoids or second-line antibiotics. Since 2000, the global incidence of MRMP has gradually increased, especially in East Asia, which has posed a serious challenge to the treatment of M. pneumoniae infections in children and attracted widespread attention from pediatricians. However, there is still no global consensus on the diagnosis and treatment of MRMP in children. METHODS: We organized 29 Chinese experts majoring in pediatric pulmonology and epidemiology to write the world's first consensus on the diagnosis and treatment of pediatric MRMP pneumonia, based on evidence collection. The evidence searches and reviews were conducted using electronic databases, including PubMed, Embase, Web of Science, CNKI, Medline, and the Cochrane Library. We used variations in terms for "macrolide-resistant", "Mycoplasma pneumoniae", "MP", "M. pneumoniae", "pneumonia", "MRMP", "lower respiratory tract infection", "Mycoplasma pneumoniae infection", "children", and "pediatric". RESULTS: Epidemiology, pathogenesis, clinical manifestations, early identification, laboratory examination, principles of antibiotic use, application of glucocorticoids and intravenous immunoglobulin, and precautions for bronchoscopy are highlighted. Early and rapid identification of gene mutations associated with MRMP is now available by polymerase chain reaction and fluorescent probe techniques in respiratory specimens. Although the resistance rate to macrolide remains high, it is fortunate that M. pneumoniae still maintains good in vitro sensitivity to second-line antibiotics such as tetracyclines and quinolones, making them an effective treatment option for patients with initial treatment failure caused by macrolide antibiotics. CONCLUSIONS: This consensus, based on international and national scientific evidence, provides scientific guidance for the diagnosis and treatment of MRMP in children. Further studies on tetracycline and quinolone drugs in children are urgently needed to evaluate their effects on the growth and development. Additionally, developing an antibiotic rotation treatment strategy is necessary to reduce the prevalence of MRMP strains.

5.
Plant Physiol Biochem ; 215: 109027, 2024 Aug 10.
Article in English | MEDLINE | ID: mdl-39154422

ABSTRACT

ATP-binding cassette (ABC) transporters are vital for plant growth and development as they facilitate the transport of essential molecules. Despite the family's significance, limited information exists about its functional distinctions in Citrus medica. Our study identified 119 genes encoding ABC transporter proteins in the C. medica genome. Through an evolutionary tree and qPCR analysis, two ABC genes, CmABCB19 and CmABCC10, were implicated in C. medica fruit development, showing upregulation in normal fruits compared to malformed fruits. CmABCB19 was found to localize to the plasma membrane of Nicotiana tabacum, exhibiting indole-3-acetic acid (IAA) efflux activity in the yeast mutant strain yap1. CmABCC10, a tonoplast-localized transporter, exhibited efflux of diosmin, nobiletin, and naringin, with rutin influx in strain ycf1. Transgenic expression of CmABCB19 and CmABCC10 in Arabidopsis thaliana induced alterations in auxin and flavonoid content, impacting silique and seed size. This effect was attributed to the modulation of structural genes in the auxin biosynthesis (YUC5/9, CYP79B2, CYP83B1, SUR1) and flavonoid biosynthesis (4CL2/3, CHS, CHI, FLS1/3) pathways. In summary, the functional characterization of CmABCB19 and CmABCC10 illuminates auxin and flavonoid transport, offering insights into their interplay with biosynthetic pathways and providing a foundation for understanding the transporter's role in fruit development.

6.
J Lipid Res ; : 100623, 2024 Aug 16.
Article in English | MEDLINE | ID: mdl-39154732

ABSTRACT

Natriuretic peptide receptor-C (NPR-C) is highly expressed in adipose tissues, and regulates obesity related diseases, however the detailed mechanism remains unknown. In this research, we aimed to explore the potential role of NPR-C in cold exposure and high-fat/high-sugar (HF/HS) diet induced metabolic changes, especially in regulating white adipose tissue (WAT) mitochondrial function. Our findings showed that NPR-C expression, especially in epididymal WAT (eWAT), was reduced after cold exposure. Global Npr3 (gene encoding NPR-C protein) deficiency led to reduced body weight, increased WAT browning, thermogenesis, and enhanced expression of genes related to mitochondrial biogenesis. RNA-sequencing of eWAT showed that Npr3 deficiency enhanced expression of mitochondrial respiratory chain complex genes and promoted mitochondrial oxidative phosphorylation in response to cold exposure. In addition, Npr3 KO mice were able to resist obesity induced by HF/HS diet. Npr3 knockdown in stromal vascular fraction (SVF)-induced white adipocytes promoted the expression of proliferator-activated receptor gamma coactivator 1α (PGC1α), uncoupling protein 1 (UCP1) and mitochondrial respiratory chain complexes. Mechanistically, NPR-C inhibited cGMP and calcium signaling in an NPR-B-dependent manner but suppressed cAMP signaling in an NPR-B-independent manner. Moreover, Npr3 knockdown induced browning via AKT and p38 pathway activation, which were attenuated by Npr2 knockdown. Importantly, treatment with the NPR-C specific antagonist, AP-811, decreased WAT mass and increased PGC-1α, UCP1 and mitochondrial complex expression. These findings demonstrate that NPR-C deficiency enhances metabolic health by boosting energy expenditure in WAT, emphasizing the potential of NPR-C inhibition for treating obesity and related metabolic disorders.

7.
Int J Biol Macromol ; 277(Pt 3): 134517, 2024 Aug 05.
Article in English | MEDLINE | ID: mdl-39111497

ABSTRACT

Fucoidan-coated pH sensitive liposomes were designed for targeted delivery of gemcitabine (FU-GEM PSL) to treat pancreatic cancer (PC). FU-GEM PSL had a particle size of 175.3 ± 4.9 nm, zeta potential of -19.0 ± 3.7 mV, encapsulation efficiency (EE) of 74.05 ± 0.17 %, and drug loading (DL) of 21.27 ± 0.05 %. Cell experiments in vitro showed that FU-GEM PSL could increase the release of GEM and drug concentration, and could inhibit tumor cell proliferation by affecting the cell cycle. FU-GEM PSL entered cells through macropinocytosis and caveolin-mediated endocytosis to exert effects. Meanwhile, the expression of P-selectin was detected in human tissues, demonstrating the feasibility of targeting FU. Moreover, combined with animal experiments in vivo, FU-GEM PSL could inhibit the development of PC. Furthermore, anti-tumor experiments in vivo carried on BALB/c mice indicated that FU-GEM PSL had tumor suppression abilities and safety. Therefore, FU-GEM PSL is a promising formulation for PC therapy.

8.
Front Endocrinol (Lausanne) ; 15: 1362077, 2024.
Article in English | MEDLINE | ID: mdl-39114290

ABSTRACT

Background: Erythrocyte dysfunction is a characteristic of diabetes mellitus (DM). However, erythrocyte-associated biomarkers do not adequately explain the high prevalence of DM. Here, we describe red blood cell distribution width to albumin ratio (RAR) as a novel inflammatory biomarker for evaluating an association with DM prevalence and prognosis of all-cause mortality. Methods: Data analyzed in this study were extracted from the National Health and Nutrition Examination Survey (NHANES) 1999-2020. A total of 40,558 participants (non-DM and DM) were enrolled in the study; RAR quartiles were calibrated at Q1 [2.02,2.82] mL/g, Q2 (2.82,3.05] mL/g, Q3 (3.05,3.38] mL/g, and Q4 (3.38,12.08] mL/g. A total of 8,482 DM patients were followed (for a median of 84 months), of whom 2,411 died and 6,071 survived. The prevalence and prognosis associated with RAR and DM were analyzed; age and sex were stratified to analyze the prevalence of RAR in DM and the sensitivity of long-term prognosis. Results: Among non-DM (n=30,404) and DM (n=10,154) volunteers, DM prevalence in RAR quartiles was 8.23%, 15.20%, 23.92%, and 36.39%. The multivariable odds ratio (OR) was significant for RAR regarding DM, at 1.68 (95% CI 1.42, 1.98). Considering Q1 as a foundation, the Q4 OR was 2.57 (95% CI 2.11, 3.13). The percentages of DM morbidity varied across RAR quartiles for dead (n=2,411) and surviving (n=6,071) DM patients. Specifically, RAR quartile mortality ratios were 20.31%, 24.24%, 22.65%, and 29.99% (P<0.0001). The multivariable hazard ratio (HR) for RAR was 1.80 (95% CI 1.57, 2.05). Considering Q1 as a foundation, the Q4 HR was 2.59 (95% CI 2.18, 3.09) after adjusting for confounding factors. Sensitivity analysis revealed the HR of male DM patients to be 2.27 (95% CI 1.95, 2.64), higher than females 1.56 (95% CI 1.31, 1.85). DM patients who were 60 years of age or younger had a higher HR of 2.08 (95% CI1.61, 2.70) as compared to those older than 60 years, who had an HR of 1.69 (95% CI 1.47, 1.94). The HR of RAR in DM patients was optimized by a restricted cubic spline (RCS) model; 3.22 was determined to be the inflection point of an inverse L-curve. DM patients with a RAR >3.22 mL/g suffered shorter survival and higher mortality as compared to those with RAR ≤3.22 mL/g. OR and HR RAR values were much higher than those of regular red blood cell distribution width. Conclusions: The predictive value of RAR is more accurate than that of RDW for projecting DM prevalence, while RAR, a DM risk factor, has long-term prognostic power for the condition. Survival time was found to be reduced as RAR increased for those aged ≤60 years among female DM patients.


Subject(s)
Diabetes Mellitus , Erythrocyte Indices , Nutrition Surveys , Humans , Male , Female , Prognosis , Middle Aged , Prevalence , Diabetes Mellitus/epidemiology , Diabetes Mellitus/blood , Adult , Aged , Biomarkers/blood , Erythrocytes/metabolism , Serum Albumin/analysis , Serum Albumin/metabolism
9.
J Org Chem ; 2024 Aug 09.
Article in English | MEDLINE | ID: mdl-39119659

ABSTRACT

A cascade oxidation/Pictet-Spengler condensation/annulation process has been developed for the one-pot total synthesis of nitramarine, nitraridine, and their analogues. The procedure proceeded with easily available quinolines and tryptophan derivatives. A simple and metal-free approach, wide substrate scope, and functional group tolerance make it applicable for the synthesis of diverse bioactive nitramarine, nitraridine, and their derivatives. Furthermore, the bioactivity evaluation has identified two promising leading compounds 5d and 5e with potent antitumor proliferative activity against breast cancer cells.

10.
Front Immunol ; 15: 1373581, 2024.
Article in English | MEDLINE | ID: mdl-39104528

ABSTRACT

Introduction: Anti-GBM diseases with IgA deposition in the mesangial region are rarely described.The factors influencing renal prognosis in patients with anti-GBM disease combined with mesangial IgA deposition are unknown. Methods: We searched the pathological reports of the First Affiliated Hospital of Zhengzhou University from 2015 to 2023 and found that a total of 72 patients with the anti-GBM disease and 25 patients combined with mesangial IgA deposition. We studied the clinical and pathological features, renal prognosis, and the factors affecting renal prognosis in patients with anti-GBM disease combined with mesangial IgA deposition. Results: Their median age was 44 years, and their age distribution was unimodal. The proportion of oliguria or anuria in patients with anti-GBM disease combined with mesangial IgA deposition was significantly lower than that in patients with classic anti-GBM disease (13.04 vs. 42.31%, p=0.030). Their 24-hour urinary protein excretion was significantly higher [median:3.25 vs. 1.12g/24h, Interquartile range(IQR):1.032~3.945 vs. 0.63~1.79g/24h, p=0.020], serum creatinine (SCr) level at the initial diagnosis was lower(median:456.0 vs. 825.5µmol/L, IQR:270.0~702.0 vs. 515.8~1231.2µmol/L, p=0.002), peak SCr level was lower (median: 601.0 vs. 907.2µmol/L, IQR: 376.5~937.0 vs. 607.0~1361.2µmol/L, p=0.007), and their serum complement 3(C3) level was higher(median: 1.275 vs. 1.015g/L, IQR:1.097~1.462 vs. 0.850~1.220g/L, p=0.027). They had better renal outcomes during follow-up (p<0.001). After adjustment for hypertension, oliguria or anuria, and crescents%, IgA deposition in the mesangial region was still an independent protective factor (p=0.003) for ESRD in anti-GBM patients. Hypertension (p=0.026) and SCr levels at initial diagnosis (p=0.004) were risk factors for renal prognosis in patients with anti-GBM disease combined with mesangial IgA deposition. Discussion: Patients with anti-GBM disease combined with mesangial IgA deposition have less severe renal impairment and better renal prognosis than patients with classic anti-GBM disease.


Subject(s)
Immunoglobulin A , Humans , Male , Female , Adult , Prognosis , Middle Aged , Anti-Glomerular Basement Membrane Disease/immunology , Anti-Glomerular Basement Membrane Disease/diagnosis , Glomerular Mesangium/pathology , Glomerular Mesangium/immunology , Glomerular Mesangium/metabolism , Glomerulonephritis, IGA/immunology , Glomerulonephritis, IGA/diagnosis , Glomerulonephritis, IGA/pathology , Retrospective Studies
11.
Macromol Rapid Commun ; : e2400429, 2024 Aug 06.
Article in English | MEDLINE | ID: mdl-39108060

ABSTRACT

Conductive hydrogels, characterized by their unique features of flexibility, biocompatibility, electrical conductivity, and responsiveness to environmental stimuli, have emerged as promising materials for sensitive strain sensors. In this study, a facile strategy to prepare highly conductive hydrogels is reported. Through rational structural and synthetic design, silver nanowires (AgNWs) are incorporated into poly(N-acryloyl glycinamide) (PNAGA) hydrogels, achieving high electrical conductivity (up to 0.88 S m-1), significantly enhanced mechanical properties, and elevated deformative sensitivity. Furthermore, surface modification with polyhexafluoropropylene oxide (PHFPO) has substantially improved the water retention capacity and dressing comfort of this hydrogel material. Based on the above merits, these hydrogels are employed to fabricate highly sensitive wearable strain sensors which can detect and interpret subtle hand and finger movements and enable precise control of machine interfaces. The AgNWs/PNAGA based strain sensors can effectively sense finger motion, enabling the control of robotic fingers to replicate the human hand's gestures. In addition, the high deformative sensitivity and elevated water retention performance of the hydrogels makes them suitable for flow sensing. These conceptual applications demonstrate the potential of this conductive hydrogel in high-performance strain sensors in the future.

12.
Transl Oncol ; 48: 102080, 2024 Oct.
Article in English | MEDLINE | ID: mdl-39116799

ABSTRACT

BACKGROUND: Gastric cancer (GC) is the fourth leading cause of cancer deaths, with advanced cases having a median survival of less than one year. Neoadjuvant chemotherapy (NCT) is vital but faces drug resistance issues, partly due to cancer-associated fibroblasts (CAFs). Yet, specific CAF subpopulations contributing to resistance are poorly understood. METHODS: Differentially expressed genes (DEGs) between chemosensitive and resistant GC patients were identified using GEO2R. Single-cell sequencing (scRNA-seq) identified CAF-related genes. Immunohistochemistry verified key genes in NCT-treated GC samples, analyzing their correlation with tumor regression grade (TRG) and clinicopathological characteristics. RESULTS: PPIC as a gene highly expressed in CAFs was closely associated with NCT resistance in gastric cancer. Immunohistochemistry results revealed positivity for the expression of cyclophilin C (CypC), encoded by PPIC, in the 5-fluorouracil and cisplatin NCT resistant and -sensitive groups of gastric cancer patients at rates of 69.7 % (76/109) and 43.6 % (24/55), respectively (p < 0.001). The high expression of CypC in CAFs was positively correlated to tumor size (p = 0.025), T stage (p = 0.004), TNM stage (p = 0.004), and vascular invasion (p = 0.027). In cancer cells the expression of CypC was associated with OS (p = 0.026). However, in CAFs, CypC expression was not related to OS (p = 0.671). CONCLUSIONS: PPIC-labeled CAF subgroups are related to NCT resistance and poor prognosis in GC and they may cause drug resistance through signaling pathways such as glucose metabolism and extracellular matrix remodeling. However, the exact mechanism behind the involvement of PPIC-labeled CAF in drug resistance of GC requires further study.

14.
Acta Pharmacol Sin ; 2024 Aug 01.
Article in English | MEDLINE | ID: mdl-39090393

ABSTRACT

Non-communicable diseases (NCDs) are defined as a kind of diseases closely related to bad behaviors and lifestyles, e.g., cardiovascular diseases, cancer, and diabetes. Driven by population growth and aging, NCDs have become the biggest disease burden in the world, and it is urgent to prevent and control these chronic diseases. Autophagy is an evolutionarily conserved process that degrade cellular senescent or malfunctioning organelles in lysosomes. Mounting evidence has demonstrated a major role of autophagy in the pathogenesis of cardiovascular diseases, cancer, and other major human diseases, suggesting that autophagy could be a candidate therapeutic target for NCDs. Natural products/phytochemicals are important resources for drugs against a wide variety of diseases. Recently, compounds from natural plants, such as resveratrol, curcumin, and ursolic acid, have been recognized as promising autophagy modulators. In this review, we address recent advances and the current status of the development of natural autophagy modulators in NCDs and provide an update of the latest in vitro and in vivo experiments that pave the way to clinical studies. Specifically, we focus on the relationship between natural autophagy modulators and NCDs, with an intent to identify natural autophagy modulators with therapeutic potential.

15.
Asian J Androl ; 2024 Aug 02.
Article in English | MEDLINE | ID: mdl-39091143

ABSTRACT

Parameters of peripheral blood cell have been shown as the potential predictors of erectile dysfunction (ED). To investigate the clinical significance of hematological parameters for predicting the risk of rapid ejaculation, we established a rat copulatory model on the basis of ejaculation distribution theory. Blood samples from different ejaculatory groups were collected for peripheral blood cell counts and serum serotonin (5-HT) tests. Meanwhile, the relationship between hematological parameters and ejaculatory behaviors was assessed. Final analysis included 11 rapid ejaculators, 10 normal ejaculators, and 10 sluggish ejaculators whose complete data were available. The platelet (PLT) count in rapid ejaculators was significantly lower than that in normal and sluggish ejaculators, whereas the platelet distribution width (PDW) and mean platelet volume (MPV) were significantly greater in rapid ejaculators. Multivariate logistic regression analysis and receiver operating characteristic (ROC) curve analysis showed that the PLT was an independent protective factor for rapid ejaculation. Meanwhile, rapid ejaculators were found to have the lowest serum 5-HT compared to normal and sluggish ejaculators (P < 0.001). Furthermore, there was a positive correlation between the PLT and serum 5-HT (r = 0.662, P < 0.001), indicating that the PLT could indirectly reflect the serum 5-HT concentration. In addition, we assessed the association between the PLT and ejaculatory parameters. There was a negative correlation between ejaculation frequency (EF) and the PLT (r = -0.595, P < 0.001), whereas there was a positive correlation between ejaculation latency (EL) and the PLT (r = 0.740, P < 0.001). This study indicated that the PLT might be a useful and convenient diagnostic marker for predicting the risk of rapid ejaculation.

16.
Histochem Cell Biol ; 2024 Aug 02.
Article in English | MEDLINE | ID: mdl-39093409

ABSTRACT

Oocyte meiotic maturation failure and chromosome abnormality is one of the main causes of infertility, abortion, and diseases. The mono-orientation of sister chromatids during the first meiosis is important for ensuring accurate chromosome segregation in oocytes. MEIKIN is a germ cell-specific protein that can regulate the mono-orientation of sister chromatids and the protection of the centromeric cohesin complex during meiosis I. Here we found that MEIKIN is a maternal protein that was highly expressed in mouse oocytes before the metaphase I (MI) stage, but became degraded by the MII stage and dramatically reduced after fertilization. Strikingly, MEIKIN underwent phosphorylation modification after germinal vesicle breakdown (GVBD), indicating its possible function in subsequent cellular event regulation. We further showed that MEIKIN phosphorylation was mediated by PLK1 at its carboxyl terminal region and its C-terminus was its key functional domain. To clarify the biological significance of meikin degradation during later stages of oocyte maturation, exogenous expression of MEIKIN was employed, which showed that suppression of MEIKIN degradation resulted in chromosome misalignment, cyclin B1 and Securin degradation failure, and MI arrest through a spindle assembly checkpoint (SAC)-independent mechanism. Exogenous expression of MEIKIN also inhibited metaphase II (MII) exit and early embryo development. These results indicate that proper MEIKIN expression level and its C-terminal phosphorylation by PLK1 are critical for regulating the metaphase-anaphase transition in meiotic oocyte. The findings of this study are important for understanding the regulation of chromosome segregation and the prevention meiotic abnormality.

17.
J Am Chem Soc ; 146(32): 22829-22839, 2024 Aug 14.
Article in English | MEDLINE | ID: mdl-39086019

ABSTRACT

The molecular editing of ketones represents an appealing strategy due to its ability to maximize the structural diversity of ketone compounds in a straightforward manner. However, developing efficient methods for the arbitrary modification of ketonic molecules, particularly those integrated within complex skeletons, remains a significant challenge. Herein, we present a unique strategy for ketone recasting that involves radical acylation of pre-functionalized ketones facilitated by N-heterocyclic carbene and photo dual catalysis. This protocol features excellent substrate tolerance and can be applied to the convergent synthesis and late-stage functionalization of structurally complex bioactive ketones. Mechanistic investigations, including experimental studies and density functional theory (DFT) calculations, shed light on the reaction mechanism and elucidate the basis of the regioselectivity.

18.
PLoS One ; 19(8): e0308202, 2024.
Article in English | MEDLINE | ID: mdl-39133688

ABSTRACT

BACKGROUND: Longer outpatient studies have demonstrated that hybrid closed loop (HCL) use has led to a concomitant reduction in glycated hemoglobin(HbA1c) by 0.3%-0.7%. However, reports have also indicated that HbA1c levels are not declined in the long-term use of HCL. Therefore, we wonder that 3 months use of HCL could improve glycated hemoglobin levels in adolescents and children with T1D. METHODS: Relevant studies were searched electronically in the Cochrane Library, PubMed, and Embase utilizing the key words "Pediatrics or Child or Adolescent", "Insulin Infusion Systems" and "Diabetes Mellitus" from inception to 17th March 2024 to evaluate the performance of HCL on HbA1c in adolescents, and children with T1D. RESULTS: Nine studies involving 927 patients were identified. Three months use of HCL show a beneficial effect on HbA1c management (p <0.001) as compared to standard of care in adolescents and children with T1D, without evidence of heterogeneity between articles (I2 = 40%, p = 0.10). HCL did significantly increase the overall average percentage of hypoglycemic time between 70 and 180 mg/dL (TIR) (p <0.001; I2 = 51%). HCL did not show a beneficial effect on hypoglycemic time <70 mg/dL and <54 mg/dL (p >0.05). The overall percentage of hyperglycemic time was significantly decreased in HCL group compared to the control group when it was defined as >180 mg/dL (p <0.001; I2 = 83%), >250 mg/dL (p = 0.007, I2 = 86%) and >300 mg/dL (p = 0.005; I2 = 76%). The mean glucose level was significantly decreased by HCL (p <0.001; I2 = 58%), however, no significant difference was found in coefficient of variation of sensor glucose (p = 0.82; I2 = 71%) and daily insulin dose (p = 0.94; I2 <0.001) between the HCL group and the control group. CONCLUSIONS: HCL had a beneficial effect on HbA1c management and TIR without increased hypoglycemic time as compared to standard of care in adolescents and children with T1D when therapy duration of HCL was not less than three months. TRIAL NUMBER AND REGISTRY URL: CRD42022367493; https://www.crd.york.ac.uk/PROSPERO, Principal investigator: Zhen-feng Zhou, Date of registration: October 30, 2022.


Subject(s)
Diabetes Mellitus, Type 1 , Glycated Hemoglobin , Insulin Infusion Systems , Humans , Glycated Hemoglobin/analysis , Adolescent , Diabetes Mellitus, Type 1/drug therapy , Diabetes Mellitus, Type 1/blood , Child , Blood Glucose/analysis , Insulin/administration & dosage , Insulin/therapeutic use , Hypoglycemic Agents/therapeutic use , Hypoglycemic Agents/administration & dosage
19.
Neural Netw ; 179: 106620, 2024 Aug 08.
Article in English | MEDLINE | ID: mdl-39137470

ABSTRACT

The recently introduced neural operator (NO) has been employed as a gain approximator in the backstepping stabilization control of first-order hyperbolic and parabolic partial differential equation (PDE) systems. Due to the global approximation ability of the DeepONet, the NO provides approximate spatial gain function with arbitrary accuracy. The closed-loop system stability can be ensured by the backstepping controller involving the approximate gain with sufficiently small error. In this paper, the NO theory is leveraged to solve the robust output regulation problem for a class of uncertain hyperbolic PDE systems under the design framework of backstepping-based regulator. The NO is trained offline on a dataset containing a sufficient number of system parameters and corresponding prior solutions of the kernel equation, so as to generate feedback gain for the robust regulator. Once the NO is trained, the kernel equation does not need to be solved ever again, for any new system parameters that do not exceed the range of the training set. Based on the internal model principle, the regulator is inherently robust to a degree of parameter uncertainty and error in approximate gain. Therefore, the tracking error can still converge to 0 if the extended regulator equations are solvable and the parameter uncertainty leads to an asymptotically stable origin. We provide a series of theory proofs and a numerical test under the approximate control and observation gains to demonstrate the robust regulation problem. It is shown that the NO is almost three orders of magnitude faster than PDE solver in generating kernel function, and the loss remains on the order of 10-4 in the test. This provides an opportunity to use the NO methodology for accelerated gain scheduling regulation for PDEs with time-varying system parameters.

20.
Proc Natl Acad Sci U S A ; 121(34): e2322938121, 2024 Aug 20.
Article in English | MEDLINE | ID: mdl-39141351

ABSTRACT

The removal of mis-incorporated nucleotides by proofreading activity ensures DNA replication fidelity. Whereas the ε-exonuclease DnaQ is a well-established proofreader in the model organism Escherichia coli, it has been shown that proofreading in a majority of bacteria relies on the polymerase and histidinol phosphatase (PHP) domain of replicative polymerase, despite the presence of a DnaQ homolog that is structurally and functionally distinct from E. coli DnaQ. However, the biological functions of this type of noncanonical DnaQ remain unclear. Here, we provide independent evidence that noncanonical DnaQ functions as an additional proofreader for mycobacteria. Using the mutation accumulation assay in combination with whole-genome sequencing, we showed that depletion of DnaQ in Mycolicibacterium smegmatis leads to an increased mutation rate, resulting in AT-biased mutagenesis and increased insertions/deletions in the homopolymer tract. Our results showed that mycobacterial DnaQ binds to the ß clamp and functions synergistically with the PHP domain proofreader to correct replication errors. Furthermore, the loss of dnaQ results in replication fork dysfunction, leading to attenuated growth and increased mutagenesis on subinhibitory fluoroquinolones potentially due to increased vulnerability to fork collapse. By analyzing the sequence polymorphism of dnaQ in clinical isolates of Mycobacterium tuberculosis (Mtb), we demonstrated that a naturally evolved DnaQ variant prevalent in Mtb lineage 4.3 may enable hypermutability and is associated with drug resistance. These results establish a coproofreading model and suggest a division of labor between DnaQ and PHP domain proofreader. This study also provides real-world evidence that a mutator-driven evolutionary pathway may exist during the adaptation of Mtb.


Subject(s)
DNA Replication , Mycobacterium smegmatis/genetics , Mycobacterium smegmatis/metabolism , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , DNA, Bacterial/genetics , DNA, Bacterial/metabolism , Mycobacterium tuberculosis/genetics , Mycobacterium tuberculosis/metabolism , Mutation
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