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1.
Int J Biol Macromol ; : 133346, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38960231

RESUMEN

The construction of N, P co-doped hierarchically porous carbons (NPHPC) by a facile and green approach is crucial for high-performance energy storage but still an enormous challenge. Herein, an environment-friendly "in-situ co-doping, self-regulation-activation" strategy is presented to one-pot synthesize NPHPC using a phytic acid-induced polyethyleneimine/chitosan gel (PEI-PA-CS) as single precursor. NPHPC displayed a specific surface area of up to 1494 m2 g-1, high specific capacitance of 449 F g-1 at 1 A g-1, outstanding rate capability and cycling durability in a wide temperature range (-20 to 60 °C). NPHPC and PEI-PA-CS electrolyte assembled symmetric quasi-solid-state flexible supercapacitor presents superb energy outputs of 27.06 Wh kg-1 at power density of 225 W kg-1. For capacitive deionization (CDI), NPHPC also exhibit an excellent salt adsorption capacity of 16.54 mg g-1 in 500 mg L-1 NaCl solution at a voltage of 1.4 V, and regeneration performance. This study provides a valuable reference for the rational design and synthesis of novel biomass-derived energy-storage materials by integrating phytic acid induced heteroatom doping and pore engineering.

2.
iScience ; 27(6): 109798, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38947509

RESUMEN

High salt (HS) consumption is a risk factor for multiple autoimmune disorders via disturbing immune homeostasis. Nevertheless, the exact mechanisms by which HS exacerbates rheumatoid arthritis (RA) pathogenesis remain poorly defined. Herein, we found that heightened phosphorylation of PDPK1 and SGK1 upon HS exposure attenuated FoxO1 expression to enhance the glycolytic capacity of CD4 T cells, resulting in strengthened Th17 but compromised Treg program. GSK2334470 (GSK), a dual PDPK1/SGK1 inhibitor, effectively mitigated the HS-induced enhancement in glycolytic capacity and the overproduction of IL-17A. Therefore, administration of GSK markedly alleviated HS-exacerbated RA progression in collagen-induced arthritis (CIA) model. Collectively, our data indicate that HS consumption subverts Th17/Treg homeostasis through the PDPK1-SGK1-FoxO1 signaling, while GSK could be a viable drug against RA progression in clinical settings.

3.
J Inflamm Res ; 17: 4065-4076, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38948196

RESUMEN

Background: Inflammation triggers atherosclerotic plaque rupture, leading to acute myocardial infarction (AMI). Following AMI, peri-coronary adipose tissue (PCAT) undergoes a transition from lipid-rich to hydrophilic characteristics due to vascular inflammation. This study investigates PCAT changes and neutrophil-to-lymphocyte ratio levels during AMI. Patients and Methods: 60 AMI patients undergoing coronary computed tomography angiography and angiography (Jan 2020-Jun 2022) were studied 60 age, gender, BMI-matched stable angina, and 60 non-coronary artery disease patients were included. Siemens VB20.0 measured PCAT-volume and fat attenuation index (FAI). Neutrophil-to-lymphocyte ratio levels were calculated by peripheral blood tests. Results: The PCAT volume and PCAT-FAI gradually increased across the control, stable angina, and AMI groups, with a corresponding gradual rise in NLR. NLR exhibited weak positive correlation with PCAT-FAI (r=0.35) and PCAT-volume (r=0.24). Multivariable logistic regression identified increased PCAT-volume, PCAT-FAI and neutrophil-to-lymphocyte ratio as possible independent AMI risk factors. No significant PCAT-volume difference was observed between infarct-related artery (IRA) and non-IRA for all three coronary arteries. Only PCAT-FAI around IRA-LAD was higher than non-IRA-LAD (-74.84±6.93 HU vs -79.04±8.68 HU). PCAT-FAI around culprit vessels in AMI was higher than corresponding lesion related vessel in SA. PCAT-volume around narrowed non-IRA in AMI was higher than that of corresponding LRV in SA. PCAT-FAI of narrowed non-IRA-LADs and non-IRA-LCXs in AMI were elevated compared to LADs (-78.46±8.56HU vs -83.13±8.34 HU) and LCXs (-73.83±10.63 HU vs -81.38±7.88 HU) of lesion related vessel in stable angina. Conclusion: We found an association between AMI and inflammation in the coronary perivascular adipose tissue and systemic inflammatory response.

4.
Front Endocrinol (Lausanne) ; 15: 1356938, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38948529

RESUMEN

Introduction: Studies on the effect of vaccine type and two other vaccines other than inactivated vaccines approved in China on in vitro fertilization (IVF) pregnancy outcomes are rare. To complement and confirm the existing findings, this research aimed to investigate whether there are adverse effects of different vaccine types in females and males on reproductive function and clinical pregnancy. Methods: This retrospective study enrolled 6,455 fresh embryo transfer cycles at the First Affiliated Hospital of Zhengzhou University between May 1, 2021, and October 31, 2022. The primary outcome is the clinical pregnancy rate (CPR). At the same time, the secondary results are the number of oocytes retrieved, two pronuclei (2PN) rate, blastocyst formation rate, high-quality blastocyst rate, and semen parameters (volume, density, sperm count, forward motility rate, total motility rate, immobility rate, and DNA fragment index (DFI) rate). Results: In the comparison of ovarian stimulation indicators, no statistically significant differences (P > 0.05) were found in Gn days, endometrial thickness, 2PN rate, metaphase 2 (MII) rate, high-quality embryo rate, and blastocyst formation rate. No significant differences (P>0.05) were found in age, body mass index (BMI), education level, and semen parameters (volume, density, sperm count, forward motility rate, total motility rate, immobility rate, and DFI rate) in these four groups. The multivariate regression model showed that neither the types of vaccines nor the vaccination status of both infertile couples significantly affected clinical pregnancy. Discussion: The type of vaccine does not appear to have an unfavorable effect on ovarian stimulation, embryo development, semen parameters, and clinical pregnancy.


Asunto(s)
Vacunas contra la COVID-19 , COVID-19 , Resultado del Embarazo , Índice de Embarazo , Humanos , Femenino , Embarazo , Masculino , Estudios Retrospectivos , Adulto , Vacunas contra la COVID-19/efectos adversos , Vacunas contra la COVID-19/administración & dosificación , COVID-19/prevención & control , COVID-19/epidemiología , Infertilidad , Fertilización In Vitro/métodos , Vacunación/efectos adversos , Inducción de la Ovulación/métodos , Reproducción/fisiología , Transferencia de Embrión/métodos , China/epidemiología , SARS-CoV-2
5.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 38(6): 696-702, 2024 Jun 15.
Artículo en Chino | MEDLINE | ID: mdl-38918190

RESUMEN

Objective: To investigate the effectiveness of HoloSight Orthopaedic Trauma Surgery Robot-assisted infra-acetabular screw placement for treatment of acetabular fractures. Methods: The clinical data of 23 patients with acetabular fractures treated with open reduction and internal fixation and infra-acetabular screw placement in two medical centers between June 2022 and October 2023 were retrospectively analyzed. According to the the method of infra-acetabular screw placement, the patients were divided into navigation group (10 cases, using HoloSight Orthopaedic Trauma Surgery Robot-assisted screw placement) and freehand group (13 cases, using traditional X-ray fluoroscopy to guide screw placement). There was no significant difference in gender, age, body mass index, cause of injury, time from injury to operation, and Judet-Letournel classification between the two groups ( P>0.05). The time of infra-acetabular screw placement, the fluoroscopy frequency, the guide pin adjustment times, the quality of screw placement, the quality of fracture reduction, and the function of hip joint were compared between the two groups. Results: All patients completed the operation successfully. The time of screw placement, the fluoroscopy frequency, and guide pin adjustment times in the navigation group were significantly less than those in the freehand group ( P<0.05). The quality of screw placement in the navigation group was significantly better than that in the freehand group ( P<0.05). Patients in both groups were followed up 6-11 months, with an average of 7.7 months. There were 9 and 9 cases in the navigation group and the freehand group who achieved excellent and good fracture reduction quality at 1 week after operation, and 12 and 12 cases with excellent and good hip joint function at last follow-up, respectively, and there was no significant difference between the two groups ( P>0.05). The fractures in both groups healed well, and there was no significant difference in healing time ( P>0.05). During the follow-up, there was no complication related to screw placement, such as failure of internal fixation, vascular and nerve injury, incisional hernia. Conclusion: In the treatment of acetabular fractures, compared with the traditional freehand screw placement, the HoloSight Orthopaedic Trauma Surgery Robot-assisted screw placement can reduce the time of screw placement, improve the accuracy of screw placement, and reduce the amount of radiation, which is an efficient, accurate, and safe surgical method.


Asunto(s)
Acetábulo , Tornillos Óseos , Fijación Interna de Fracturas , Fracturas Óseas , Procedimientos Quirúrgicos Robotizados , Humanos , Acetábulo/lesiones , Acetábulo/cirugía , Fijación Interna de Fracturas/métodos , Fijación Interna de Fracturas/instrumentación , Estudios Retrospectivos , Fracturas Óseas/cirugía , Procedimientos Quirúrgicos Robotizados/métodos , Fluoroscopía , Resultado del Tratamiento , Cirugía Asistida por Computador/métodos , Masculino , Femenino , Adulto , Cirugía de Cuidados Intensivos
6.
J Tissue Viability ; 2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38906753

RESUMEN

OBJECTIVE: Moisture-associated skin damage (MASD) is an inflammatory skin condition caused by long-term exposure to a moist environment, which can compromise the integrity of the barrier and increase pain. This scoping review aimed to systematically analyze the research status of prevention and care for MASD. METHODS: We conducted a scoping review following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews. PubMed, MEDLINE, Scopus, Web of Science, CINAHL, and the Cochrane Database of Systematic Reviews were searched for relevant articles until March 2023. RESULTS: Based on eligibility criteria, 34 research studies and review articles were included. The prevalence of MASD varies greatly in different medical environments and patient groups. The high-risk factors included prolonged exposure to excessive water, chemical irritation such as urine or feces, mechanical factors such as friction or improper removal of medical adhesives and local bacterial colonization. Prevention measures mainly include avoiding skin exposure to moisture, skin cleansing, moisturizing and the treatment of secondary bacterial infection. CONCLUSION: A variety of factors have an impact on MASD. Nurses should select suitable tools to screen high-risk patients and take targeted preventive measures according to the related types of skin injury to reduce the incidence of MASD.

7.
Pharm Res ; 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38918308

RESUMEN

PURPOSE: Joint destruction is a major burden and an unsolved problem in rheumatoid arthritis (RA) patients. We designed an intra-articular mesoporous silica nanosystem (MSN-TP@PDA-GlcN) with anti-inflammatory and joint protection effects. The nanosystem was synthesized by encapsulating triptolide (TP) in mesoporous silica nanoparticles and coating it with pH-sensitive polydopamine (PDA) and glucosamine (GlcN) grafting on the PDA. The nano-drug delivery system with anti-inflammatory and joint protection effects should have good potency against RA. METHODS: A template method was used to synthesize mesoporous silica (MSN). MSN-TP@PDA-GlcN was synthesized via MSN loading with TP, coating with PDA and grafting of GlcN on PDA. The drug release behavior was tested. A cellular inflammatory model and a rat RA model were used to evaluate the effects on RA. In vivo imaging and microdialysis (MD) system were used to analyze the sustained release and pharmacokinetics in RA rats. RESULTS: TMSN-TP@PDA-GlcN was stable, had good biocompatibility, and exhibited sustained release of drugs in acidic environments. It had excellent anti-inflammatory effects in vitro and in vivo. It also effectively repaired joint destruction in vivo without causing any tissue toxicity. In vivo imaging and pharmacokinetics experiments showed that the nanosystem prolonged the residence time, lowered the Cmax value and enhanced the relative bioavailability of TP. CONCLUSIONS: These results demonstrated that MSN-TP@PDA-GlcN sustained the release of drugs in inflammatory joints and produced effective anti-inflammatory and joint protection effects on RA. This study provides a new strategy for the treatment of RA.

8.
Mol Ther ; 2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38822524

RESUMEN

Dysregulated T cell activation underpins the immunopathology of rheumatoid arthritis (RA), yet the machineries that orchestrate T cell effector program remain incompletely understood. Herein, we leveraged bulk and single-cell RNA sequencing data from RA patients and validated protein disulfide isomerase family A member 3 (PDIA3) as a potential therapeutic target. PDIA3 is remarkably upregulated in pathogenic CD4 T cells derived from RA patients and positively correlates with C-reactive protein level and disease activity score 28. Pharmacological inhibition or genetic ablation of PDIA3 alleviates RA-associated articular pathology and autoimmune responses. Mechanistically, T cell receptor signaling triggers intracellular calcium flux to activate NFAT1, a process that is further potentiated by Wnt5a under RA settings. Activated NFAT1 then directly binds to the Pdia3 promoter to enhance the expression of PDIA3, which complexes with STAT1 or PKM2 to facilitate their nuclear import for transcribing T helper 1 (Th1) and Th17 lineage-related genes, respectively. This non-canonical regulatory mechanism likely occurs under pathological conditions, as PDIA3 could only be highly induced following aberrant external stimuli. Together, our data support that targeting PDIA3 is a vital strategy to mitigate autoimmune diseases, such as RA, in clinical settings.

9.
BMC Microbiol ; 24(1): 206, 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38858614

RESUMEN

OBJECTIVE: This study aims to examine the impact of PE/PPE gene mutations on the transmission of Mycobacterium tuberculosis (M. tuberculosis) in China. METHODS: We collected the whole genome sequencing (WGS) data of 3202 M. tuberculosis isolates in China from 2007 to 2018 and investigated the clustering of strains from different lineages. To evaluate the potential role of PE/PPE gene mutations in the dissemination of the pathogen, we employed homoplastic analysis to detect homoplastic single nucleotide polymorphisms (SNPs) within these gene regions. Subsequently, logistic regression analysis was conducted to analyze the statistical association. RESULTS: Based on nationwide M. tuberculosis WGS data, it has been observed that the majority of the M. tuberculosis burden in China is caused by lineage 2 strains, followed by lineage 4. Lineage 2 exhibited a higher number of transmission clusters, totaling 446 clusters, of which 77 were cross-regional clusters. Conversely, there were only 52 transmission clusters in lineage 4, of which 9 were cross-regional clusters. In the analysis of lineage 2 isolates, regression results showed that 4 specific gene mutations, PE4 (position 190,394; c.46G > A), PE_PGRS10 (839,194; c.744 A > G), PE16 (1,607,005; c.620T > G) and PE_PGRS44 (2,921,883; c.333 C > A), were significantly associated with the transmission of M. tuberculosis. Mutations of PE_PGRS10 (839,334; c.884 A > G), PE_PGRS11 (847,613; c.1455G > C), PE_PGRS47 (3,054,724; c.811 A > G) and PPE66 (4,189,930; c.303G > C) exhibited significant associations with the cross-regional clusters. A total of 13 mutation positions showed a positive correlation with clustering size, indicating a positive association. For lineage 4 strains, no mutations were found to enhance transmission, but 2 mutation sites were identified as risk factors for cross-regional clusters. These included PE_PGRS4 (338,100; c.974 A > G) and PPE13 (976,897; c.1307 A > C). CONCLUSION: Our results indicate that some PE/PPE gene mutations can increase the risk of M. tuberculosis transmission, which might provide a basis for controlling the spread of tuberculosis.


Asunto(s)
Mutación , Mycobacterium tuberculosis , Polimorfismo de Nucleótido Simple , Tuberculosis , Secuenciación Completa del Genoma , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/clasificación , Mycobacterium tuberculosis/aislamiento & purificación , China/epidemiología , Humanos , Tuberculosis/transmisión , Tuberculosis/microbiología , Tuberculosis/epidemiología , Genoma Bacteriano , Femenino , Masculino , Proteínas Bacterianas/genética , Adulto
10.
Adv Sci (Weinh) ; : e2401648, 2024 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-38874068

RESUMEN

Efficient topical drug delivery remains a significant challenge in glaucoma management. Although nanoparticle formulations offer considerable promise, their complex preparation processes, co-delivery issues, and batch consistency have hindered their potential. A scalable fabrication strategy is developed here for preparing solid drug nanoparticles (SDNs) with enhanced drug delivery efficiency. Utilizing hydrophobic antiglaucoma drugs brimonidine (BM) and betaxolol (BX), uniform fixed combination BM/BX SDNs are fabricated through a continuous process, improving batch-to-batch consistency for combined glaucoma treatment. With trehalose being used as a lyoprotectant, BM/BX SDNs can be stored as dry powder and easily reconstituted in phosphate buffered saline. Importantly, reconstituted BM/BX SDNs form clear, homogenous solutions, and exhibit negligible cytotoxicity and irritation, making them well-suited for topical administration as eyedrops. Ex vivo and in vivo studies demonstrated that topically applied BM/BX SDNs permeate through the cornea significantly (about two fold to three fold) compared to their hydrophilic counterparts, i.e., brimonidine tartrate, and betaxolol hydrogen chloride. Notably, BM/BX SDNs displayed consistent intraocular pressure lowering effects in vivo in both normotensive rats and glaucoma mice. Collectively, this study demonstrates the potential of the scalable fabrication strategy and the resultant BM/BX SDNs for improving glaucoma management through eyedrops.

11.
BMC Geriatr ; 24(1): 487, 2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38831261

RESUMEN

BACKGROUND: Many older adult patients receive low-dose teicoplanin with varied regimens, leading to a lack of clarity on its optimal regimens and toxicity profiles in China. This study aimed to clarify these aspects by analyzing teicoplanin treatment concentrations and toxicities. METHODS: We included older adult patients administered teicoplanin at four tertiary hospitals in Beijing from June 2021 to July 2023, targeting a trough concentration (Cmin) ≥ 10 mg/L. Teicoplanin concentrations and toxicities were monitored dynamically. RESULTS: From 204 patients, we obtained 632 teicoplanin concentrations. Most patients (83.3%) received low-dose regimens. Suboptimal concentrations were found in 66.4% of patients within 7 days of treatment and 17.0% after 15 days. Cmin gradually increased with treatment duration and was influenced initially by creatinine and by both body weight and creatinine from days 8 to 14. The target concentration was achieved in 53.1%, 33.9%, 15.6%, and 5.5% of patients at 3, ≤ 7, 8-14, and ≥ 15 days after withdrawal, respectively. Slow elimination was associated with average Cmin and eGFR. Nephrotoxicity, hepatotoxicity, and thrombocytopenia occurred in 12.5%, 4.1%, and 31.5% of patients, respectively, without significant differences between concentrations. CONCLUSIONS: Most older adult patients were underdosed, indicating a need for dose adjustment. Given the varied risk factors for suboptimal concentrations in different treatment stages, a one-size-fits-all regimen was ineffective. We recommend an initial dose of 400 mg at 12-h intervals for the first three days, with subsequent doses from days 4 to 14 adjusted based on creatinine and body weight; after day 14, a maintenance dose of 200 mg daily is advised. TRIAL REGISTRATION: ChiCTR2100046811; 28/05/2021.


Asunto(s)
Antibacterianos , Relación Dosis-Respuesta a Droga , Teicoplanina , Humanos , Masculino , Anciano , Femenino , Estudios Prospectivos , Teicoplanina/administración & dosificación , Teicoplanina/efectos adversos , China/epidemiología , Antibacterianos/administración & dosificación , Antibacterianos/efectos adversos , Anciano de 80 o más Años , Persona de Mediana Edad
12.
Nat Commun ; 15(1): 4793, 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38839767

RESUMEN

Chiral amides are important structure in many natural products and pharmaceuticals, yet their efficient synthesis from simple amide feedstock remains challenge due to its weak Lewis basicity. Herein, we describe our study of the enantioselective synthesis of chiral amides by N-alkylation of primary amides taking advantage of an achiral rhodium and chiral squaramide co-catalyzed carbene N-H insertion reaction. This method features mild condition, rapid reaction rate (in all cases 1 min) and a wide substrate scope with high yield and excellent enantioselectivity. Further product transformations show the synthetic potential of this reaction. Mechanistic studies reveal that the non-covalent interactions between the catalyst and reaction intermediate play a critical role in enantiocontrol.

13.
Bioact Mater ; 40: 1-18, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-38873262

RESUMEN

Previous studies have confirmed that intervertebral disc degeneration (IDD) is closely associated with inflammation-induced reactive oxygen species (ROS) and resultant cell mitochondrial membrane potential (MMP) decline. Clearance of ROS in an inflammatory environment is essential for breaking the vicious cycle of MMP decline. Additionally, re-energizing the mitochondria damaged in the inflammatory milieu to restore their function, is equally important. Herein, we proposed an interesting concept of mitochondrion-engine equipped with coolant, which enables first to "cool-down" the inflammatory environment, next to restore the MMP, finally to allow cells to regain normal energy metabolism through materials design. As such, we developed a multi-functional composite composed of a reactive oxygen species (ROS)-responsive sodium alginate/gelatin hydrogel infused into a rigid 3D-printed thermoplastic polyurethane (TPU) scaffold. The TPU scaffold was coated with conductive polypyrrole (PPy) to electrophoretically deposit l-arginine, which could upregulate the Mammalian target of rapamycin (mTOR) pathway, thus increasing MMP and energy metabolism to stimulate extracellular matrix synthesis for IVD repair. While the ROS-responsive hydrogel acting as the "mito-engine coolant" could scavenge the excessive ROS to create a favorable environment for IVD cells recovery. Demonstrated by in vitro and in vivo evaluations, the mito-engine system markedly promoted the proliferation and collagen synthesis of nucleus pulposus cells while enhancing the mitochondrial respiration and MMP under oxidative stress. Radiological and histological assessments in vivo revealed the efficacy of this system in IVD repair. This unique bioinspired design integrated biomaterial science with mitochondrial biology, presents a promising paradigm for IDD treatment.

15.
Br J Cancer ; 2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38834745

RESUMEN

BACKGROUND: Diffuse invasion remains a primary cause of treatment failure in pediatric high-grade glioma (pHGG). Identifying cellular driver(s) of pHGG invasion is needed for anti-invasion therapies. METHODS: Ten highly invasive patient-derived orthotopic xenograft (PDOX) models of pHGG were subjected to isolation of matching pairs of invasive (HGGINV) and tumor core (HGGTC) cells. RESULTS: pHGGINV cells were intrinsically more invasive than their matching pHGGTC cells. CSC profiling revealed co-positivity of CD133 and CD57 and identified CD57+CD133- cells as the most abundant CSCs in the invasive front. In addition to discovering a new order of self-renewal capacities, i.e., CD57+CD133- > CD57+CD133+ > CD57-CD133+ > CD57-CD133- cells, we showed that CSC hierarchy was impacted by their spatial locations, and the highest self-renewal capacities were found in CD57+CD133- cells in the HGGINV front (HGGINV/CD57+CD133- cells) mediated by NANOG and SHH over-expression. Direct implantation of CD57+ (CD57+/CD133- and CD57+/CD133+) cells into mouse brains reconstituted diffusely invasion, while depleting CD57+ cells (i.e., CD57-CD133+) abrogated pHGG invasion. CONCLUSION: We revealed significantly increased invasive capacities in HGGINV cells, confirmed CD57 as a novel glioma stem cell marker, identified CD57+CD133- and CD57+CD133+ cells as a new cellular driver of pHGG invasion and suggested a new dual-mode hierarchy of HGG stem cells.

16.
J Physiol ; 602(12): 2751-2762, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38695322

RESUMEN

There is a growing appreciation that regulation of muscle contraction requires both thin filament and thick filament activation in order to fully activate the sarcomere. The prevailing mechano-sensing model for thick filament activation was derived from experiments on fast-twitch muscle. We address the question whether, or to what extent, this mechanism can be extrapolated to the slow muscle in the hearts of large mammals, including humans. We investigated the similarities and differences in structural signatures of thick filament activation in porcine myocardium as compared to fast rat extensor digitorum longus (EDL) skeletal muscle under relaxed conditions and sub-maximal contraction using small angle X-ray diffraction. Thick and thin filaments were found to adopt different structural configurations under relaxing conditions, and myosin heads showed different changes in configuration upon sub-maximal activation, when comparing the two muscle types. Titin was found to have an X-ray diffraction signature distinct from those of the overall thick filament backbone, and its spacing change appeared to be positively correlated to the force exerted on the thick filament. Structural changes in fast EDL muscle were found to be consistent with the mechano-sensing model. In porcine myocardium, however, the structural basis of mechano-sensing is blunted suggesting the need for additional activation mechanism(s) in slow cardiac muscle. These differences in thick filament regulation can be related to their different physiological roles where fast muscle is optimized for rapid, burst-like, contractions, and the slow cardiac muscle in large mammalian hearts adopts a more finely tuned, graded response to allow for their substantial functional reserve. KEY POINTS: Both thin filament and thick filament activation are required to fully activate the sarcomere. Thick and thin filaments adopt different structural configurations under relaxing conditions, and myosin heads show different changes in configuration upon sub-maximal activation in fast extensor digitorum longus muscle and slow porcine cardiac muscle. Titin has an X-ray diffraction signature distinct from those of the overall thick filament backbone and this titin reflection spacing change appeared to be directly proportional to the force exerted on the thick filament. Mechano-sensing is blunted in porcine myocardium suggesting the need for additional activation mechanism(s) in slow cardiac muscle. Fast skeletal muscle is optimized for rapid, burst-like contractions, and the slow cardiac muscle in large mammalian hearts adopts a more finely tuned graded response to allow for their substantial functional reserve.


Asunto(s)
Miocardio , Animales , Porcinos , Miocardio/metabolismo , Conectina/metabolismo , Ratas , Masculino , Fibras Musculares de Contracción Rápida/fisiología , Fibras Musculares de Contracción Rápida/metabolismo , Sarcómeros/fisiología , Sarcómeros/metabolismo , Fibras Musculares de Contracción Lenta/fisiología , Fibras Musculares de Contracción Lenta/metabolismo , Músculo Esquelético/fisiología , Músculo Esquelético/metabolismo , Difracción de Rayos X , Contracción Muscular/fisiología , Miosinas/metabolismo , Miosinas/fisiología
17.
Poult Sci ; 103(7): 103863, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38810566

RESUMEN

The introduction of exotic breeds and the cultivation of new lines by breeding companies have posed challenges to native chickens in South China, including loss of breed characteristics, decreased genetic diversity, and declining purity. Understanding the population genetic structure and genetic diversity of native chickens in South China is crucial for further advancements in breeding efforts. In this study, we analyzed the population genetic structure and genetic diversity of 321 individuals from 10 different breeds in South China. By comparing commercial chickens with native ones, we identified selection signatures occurring between local chickens and commercial breeds. The analysis of population genetic structure revealed that the native chicken populations in South China exhibited a considerable level of genetic diversity. Moreover, the commercial lines of Xiaobai chicken and Huangma chicken displayed even higher levels of genetic diversity, which distinguished them from other native varieties at the clustering level. However, certain individuals within these commercial varieties showed a discernible genetic relationship with the native populations. Notably, both commercial varieties also retained a significant degree of genetic similarity to their respective native counterparts. In order to investigate the genomic changes occurring during the commercialization of native chickens, we employed 4 methods (Fst, ROD, XPCLR, and XPEHH) to identify potential candidate regions displaying selective signatures in Southern Chinese native chicken population. A total of 168 (identified by Fst and ROD) and 86 (identified by XPCLR and XPEHH) overlapping genes were discovered. Functional annotation analysis revealed that these genes may be associated with reproduction and growth (SAMSN1, HYLS1, ROBO3, FGF14, PRSS23), musculoskeletal development (DNER, MYBPC1, DGKB, ORC1, KLF10), disease resistance and environmental adaptability (PUS3, CRB2, CALD1, USP15, SGCD, LTBP1), as well as egg production (ADGRB3, ACSF3). Overall, native chickens in South China harbor numerous selective sweep regions compared to commercial chickens, enriching valuable genomic resources for future genetic research and breeding conservation.


Asunto(s)
Pollos , Variación Genética , Animales , Pollos/genética , China , Selección Genética , Cruzamiento , Genética de Población
18.
Photodiagnosis Photodyn Ther ; 48: 104231, 2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38821238

RESUMEN

BACKGROUND: Chordoma is a rare congenital low-grade malignant tumor characterized by infiltrative growth. It often tends to compress important intracranial nerves and blood vessels, making its surgical treatment extremely difficult. Besides, the efficacy of radiotherapy and chemotherapy is limited. The photosensitizer hematoporphyrin derivative (HPD) can emit red fluorescence under 405 nm excitation and produce reactive oxygen species for tumor therapy under 630 nm excitation. Herein, we investigated the effects of the photosensitizer hematoporphyrin derivative (HPD) on different cell lines of chordoma and xenograft tumors under 405 nm and 630 nm excitation. METHODS: The photosensitizer hematoporphyrin derivative (HPD) and Two different chordoma cell lines (U-CH1, JHC7) were used for the test. The in vitro experiments were as follows: (1) the fluorescence intensity emitted by chordoma cells excited by different 405 nm light intensities was observed under a confocal microscope; (2) the Cell Counting Kit-8 (CCK-8) assay was performed to detect the effects of different photosensitizer concentrations and 630 nm light energy densities on the activity of chordoma cells. In the in vivo experiments, (3) Fluorescence visualization of chordoma xenograft tumors injected with photosensitizer via tail vein under 405 nm excitation; (4) Impact of 630 nm excitation of photosensitizer on the growth of chordoma xenograft tumors. RESULTS: (1) The photosensitizers in chordoma cells and chordoma xenografts of nude mice were excited by 405 nm to emit red fluorescence; (2) 630 nm excitation photosensitizer reduces chordoma cell activity and inhibits chordoma xenograft tumor growth in chordoma nude mice. CONCLUSION: Photodynamic techniques mediated by the photosensitizer hematoporphyrin derivatives can be used for the diagnosis and treatment of chordoma.

19.
Nat Commun ; 15(1): 3901, 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38724505

RESUMEN

Activation of the NF-κB pathway is strictly regulated to prevent excessive inflammatory and immune responses. In a well-known negative feedback model, IκBα-dependent NF-κB termination is a delayed response pattern in the later stage of activation, and the mechanisms mediating the rapid termination of active NF-κB remain unclear. Here, we showed IκBα-independent rapid termination of nuclear NF-κB mediated by CLK2, which negatively regulated active NF-κB by phosphorylating the RelA/p65 subunit of NF-κB at Ser180 in the nucleus to limit its transcriptional activation through degradation and nuclear export. Depletion of CLK2 increased the production of inflammatory cytokines, reduced viral replication and increased the survival of the mice. Mechanistically, CLK2 phosphorylated RelA/p65 at Ser180 in the nucleus, leading to ubiquitin‒proteasome-mediated degradation and cytoplasmic redistribution. Importantly, a CLK2 inhibitor promoted cytokine production, reduced viral replication, and accelerated murine psoriasis. This study revealed an IκBα-independent mechanism of early-stage termination of NF-κB in which phosphorylated Ser180 RelA/p65 turned off posttranslational modifications associated with transcriptional activation, ultimately resulting in the degradation and nuclear export of RelA/p65 to inhibit excessive inflammatory activation. Our findings showed that the phosphorylation of RelA/p65 at Ser180 in the nucleus inhibits early-stage NF-κB activation, thereby mediating the negative regulation of NF-κB.


Asunto(s)
Citoplasma , Inhibidor NF-kappaB alfa , FN-kappa B , Proteínas Tirosina Quinasas , Factor de Transcripción ReIA , Animales , Fosforilación , Inhibidor NF-kappaB alfa/metabolismo , Inhibidor NF-kappaB alfa/genética , Ratones , Factor de Transcripción ReIA/metabolismo , Humanos , Proteínas Tirosina Quinasas/metabolismo , Proteínas Tirosina Quinasas/genética , FN-kappa B/metabolismo , Citoplasma/metabolismo , Proteolisis , Núcleo Celular/metabolismo , Replicación Viral , Células HEK293 , Transducción de Señal , Ratones Endogámicos C57BL , Citocinas/metabolismo , Transporte Activo de Núcleo Celular , Proteínas Serina-Treonina Quinasas
20.
Chemistry ; : e202401389, 2024 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-38779789

RESUMEN

Transition metal-catalyzed epoxidation of carbonyl compounds through carbonyl ylides represents a highly effective method for synthesizing a diverse range of valuable epoxides. This review offers an in-depth overview of the latest developments in inter- and intramolecular epoxidation reactions involving metal carbenes and carbonyl compounds, encompassing both racemic to enantioselective transformations. These catalytic epoxidations are reviewed by highlighting their product selectivity, diversity and applicability, and the related mechanistic rationale is showcased where possible.

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