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1.
Small Methods ; : e2401101, 2024 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-39380428

RESUMEN

Graphene (Gr) and carbon nanotubes (CNTs), the two intriguing carbon nanomaterials, have presented great potential in serving as high-performance electrocatalysts in lithium-sulfur (Li-S) chemistry. The concurrent management of both materials would achieve a promoted synergistic effect. Nevertheless, there still remains a lack of an effective material synthesis route. Herein, a single-step plasma-enhanced chemical vapor deposition (PECVD) strategy is devised to prepare Gr@CNTs heterostructures with strong bonded connections. In the PECVD system, the damaged sidewalls generated in CNT tubes can serve as appropriate nucleation sites for further Gr growth. The formation mechanisms are thoroughly explored in aspects of both experimental characterizations and theoretical calculations. To confirm the validity of this approach, thus-constructed Gr@CNTs architectures are employed as the sulfur host, enabling boosted redox kinetics of polysulfides. This project provides fundamental insight into the mechanism exploration for single-step PECVD growth of Gr@CNTs heterostructure, hence promoting the practical application prospect of carbon nanomaterials toward Li-S systems.

2.
Infection ; 2024 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-39419957

RESUMEN

Targeted next-generation sequencing (tNGS) offers a high-throughput, culture-independent approach that delivers a comprehensive resistance profile in a significantly shorter turn-around time, making it promising in enhancing tuberculosis (TB) diagnosis and informing treatment decisions. This study aims to evaluate the performance of tNGS in the TB diagnosis and drug resistance detection of Mycobacterium tuberculosis (MTB) using MTB clinical isolates and bronchoalveolar lavage fluid (BALF) samples. A total of 143 MTB clinical isolates were assessed, tNGS, phenotypic antimicrobial susceptibility testing (AST), and AST based on whole genome sequencing (WGS) exhibited high concordance rates, averaging 95.10% and 97.05%. Among 158 BALF samples, culture, Xpert MTB/RIF, and tNGS reported 29, 70 and 111 positives, respectively. In the confirmed cases with etiological evidence (smears, cultures, or molecular test), the positive rate of tNGS (73/83, 87.95%) was higher than that of Xpert MTB (67/83, 80.72%). Additionally, 45% (27/60) of clinically diagnosed cases (with imaging or immunological evidence) were positive for tNGS. Further validation on the discrepant results between tNGS and Xpert MTB/RIF with droplet digital PCR (ddPCR) yielded 35 positives, tNGS detected all, and Xpert MTB/RIF only identified 6 positives. In conclusion, tNGS demonstrates robust and rapid performance in the identification of MTB and its associated drug resistance, and can be directly applied to clinical samples, positioning it as a promising approach for laboratory testing of tuberculosis.

3.
J Cosmet Dermatol ; 2024 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-39291439

RESUMEN

BACKGROUNDS: With the increasing demand for beauty and a healthy lifespan, studies regarding anti-skin aging have drawn much more attention than ever before. Skin cellular senescence, the primary cause of skin aging, is characterized by a cell cycle arrest in proliferating cells along with a senescence-associated secretory phenotype (SASP), which can be triggered by various internal or external stimuli. AIMS: Recent studies have made significant progress in the fields of anti-senescence and anti-aging. However, little is known about the roles and functions of natural compounds, particularly flavonoids, in skin cellular senescence studies. METHODS: In this study, using strategies including ionizing radiation (IR), senescence-associated ß galactosidase assay (SA-ß-Gal), immunofluorescence (IF), flow cytometry, PCR array, as well as in vivo experiments, we investigated the effects and roles of troxerutin (Trx), a natural flavonoid, in skin keratinocyte senescence. RESULTS: We found that Trx delays skin keratinocyte senescence induced by IR. Mechanistically, Trx protects the skin keratinocyte cells from senescence by alleviating reactive oxygen species (ROS) accumulation, mitochondrial dysfunction, and DNA damage caused by IR. In addition, Trx was also proved to relieve skin senescence and SASP secretion in vivo induced by IR stimulation. CONCLUSIONS: Altogether, our findings pointed to a new function of Trx in delaying stress-induced skin keratinocyte senescence, and should thus provide theoretical foundations for exploring novel strategies against skin aging.

4.
Zhongguo Dang Dai Er Ke Za Zhi ; 26(9): 954-960, 2024.
Artículo en Chino | MEDLINE | ID: mdl-39267511

RESUMEN

A 5-year-old girl was admitted due to one episode of melena and one episode of hematemesis. Upon admission, gastroscopy revealed esophageal and gastric varices. Abdominal CT scan, MRI, and color Doppler ultrasound suggested cirrhosis, intrahepatic bile duct dilation, and bilateral kidney enlargement. Genetic testing identified compound heterozygous mutations in the PKHD1 gene: c.2264C>T (p.Pro755Leu) and c.1886T>C (p.Val629Ala). The c.2264C>T (p.Pro755Leu) mutation is a known pathogenic variant with previous reports, while c.1886T>C (p.Val629Ala) is a novel mutation predicted to have pathogenic potential according to Mutation Taster and PolyPhen2. The child was diagnosed with autosomal recessive polycystic kidney disease. In children presenting with gastrointestinal bleeding without obvious causes, particularly those with liver or kidney disease, consideration should be given to the possibility of autosomal recessive polycystic kidney disease, and genetic testing should be conducted for definitive diagnosis when necessary.


Asunto(s)
Riñón Poliquístico Autosómico Recesivo , Humanos , Femenino , Riñón Poliquístico Autosómico Recesivo/genética , Riñón Poliquístico Autosómico Recesivo/complicaciones , Preescolar , Mutación , Receptores de Superficie Celular/genética
5.
Theranostics ; 14(12): 4861-4873, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39239515

RESUMEN

Rationale: Theranostic nanoplatforms exert a vital role in facilitating concurrent real-time diagnosis and on-demand treatment of diseases, thereby making contributions to the improvement of therapeutic efficacy. Nevertheless, the structural intricacy and the absence of well-defined integration of dual functionality persist as challenges in the development of theranostic nanoplatforms. Methods: We develop an atomically precise theranostic nanoplatform based on metal-organic cage (MOC) to provide magnetic resonance imaging (MRI) guided chemodynamic therapy (CDT) for cancer therapy and assess the theranostic performance both in vitro and in vivo. Through UV-vis spectroscopy, electron paramagnetic resonance (EPR), confocal microscopy, flow cytometry, immunofluorescence staining, and western blotting, the ability of MOC-Mn to generate •OH and the subsequent inhibition of HeLa cells was confirmed. Results: The MOC-Mn composed of manganese and calixarene was successfully synthesized and comprehensively characterized. The catalytic activity of manganese within MOC-Mn facilitated the efficient generation of hydroxyl radicals (•OH) through a Fenton-like reaction, leveraging the high concentrations of hydrogen peroxide in the tumor microenvironment (TME). Additionally, its capacity to prolong the T1 relaxation time and augment the MR signal was observed. The theranostic efficacy was verified via rigorous in vitro and in vivo experiments, indicating that MOC-Mn offered clearer visualization of tumor particulars and substantial suppression of tumor growth. Conclusion: This study showcases a precise MRI-guided CDT theranostic nanoplatform for cancer therapy, thereby promoting the advancement of precise nanomedicine and structure-function research.


Asunto(s)
Imagen por Resonancia Magnética , Nanomedicina Teranóstica , Nanomedicina Teranóstica/métodos , Humanos , Animales , Células HeLa , Imagen por Resonancia Magnética/métodos , Ratones , Manganeso/química , Ratones Desnudos , Femenino , Radical Hidroxilo/metabolismo , Radical Hidroxilo/química , Neoplasias/tratamiento farmacológico , Neoplasias/diagnóstico por imagen , Ratones Endogámicos BALB C , Estructuras Metalorgánicas/química , Estructuras Metalorgánicas/farmacología , Nanopartículas/química
6.
J Am Chem Soc ; 146(36): 25321-25327, 2024 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-39219069

RESUMEN

Cyclohexene cannot be polymerized via ring-opening polymerization under any conditions due to its lack of ring strain. A hypothetical polycyclohexene would therefore have a strong thermodynamic driving force to depolymerize to monomer if a metathesis catalyst were provided while otherwise having thermal and hydrolytic stability under normal conditions because of its hydrocarbon backbone. We envisioned access to this otherwise unattainable family of polymers via the alternating polymerization of a diene and an alkene. Ethyl aluminum chloride was found to promote highly alternating polymerization of butadiene and methacrylate when radically initiated at room temperature, resulting in formal polycyclohexene structures. Ultrahigh molecular weight (up to 1750 kDa) polymers can be synthesized at the decagram scale in high monomer conversions. The resulting presumably atactic copolymers exhibited semicrystallinity, leading to high toughness. In the presence of a small amount of the Grubbs catalyst, the generated polycyclohexene can be fully depolymerized at ambient temperatures into pure constituent cyclohexene. The strategy of using orthogonal chemistry for the polymerization and depolymerization processes allows access to polymer structures with subambient ceiling temperatures without using ultralow temperature synthesis or relying on the monomer-polymer equilibrium.

7.
J Mater Chem B ; 12(36): 9018-9029, 2024 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-39158001

RESUMEN

The primary tumor ("root") and circulating tumor cells (CTCs; "seeds") are vital factors in tumor progression. However, current treatment strategies mainly focus on inhibiting the tumor while ignoring CTCs, resulting in tumor metastasis. Here, we design a multifunctional 3D scaffold with interconnected macropores, excellent photothermal ability and perfect bioaffinity as a blood vessel implantable device. When implanted upstream of the primary tumor, the scaffold intercepts CTCs fleeing back to the primary tumor and then forms "micro-thrombi" to block the supply of nutrients and oxygen to the tumor for embolization therapy. The scaffold implanted downstream of the tumor efficiently captures and photothermally kills the CTCs that escape from the tumor, thereby preventing metastasis. Experiments using rabbits demonstrated excellent biosafety of this scaffold with 86% of the CTC scavenging rate, 99% of the tumor inhibition rate and 100% of CTC killing efficiency. The multifunctional 3D scaffold synergistically inhibits the "root" and eliminates the "seeds" of the tumor, demonstrating its potential for localized cancer therapy with few side effects and high antitumor efficacy.


Asunto(s)
Células Neoplásicas Circulantes , Células Neoplásicas Circulantes/patología , Animales , Conejos , Humanos , Embolización Terapéutica , Andamios del Tejido/química , Antineoplásicos/química , Antineoplásicos/farmacología , Línea Celular Tumoral , Tamaño de la Partícula
8.
IUBMB Life ; 2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-39139071

RESUMEN

Senescent cells are typically characterized by a stable proliferation arrested in dividing cells accompanied with a senescence-associated secretory phenotype (SASP). Skin cellular senescence is the primary cause of skin aging, whereas the lack of identified skin senescence markers limits our understanding of the mechanisms involved in skin aging. Recent studies have revealed that intracellular calcium signaling has emerged as a key player in regulating cellular senescence and aging. However, the implication and roles of calcium signaling in skin keratinocyte senescence remain only partially understood. In this study, we developed a model for skin keratinocyte senescence using ionizing radiation (I/R) stimulation and found that the calcium-associated gene transglutaminase 2 (TGM2) was significantly induced compared with normal control. Interestingly, inhibition of TGM2 was found to delay skin keratinocyte senescence by suppressing I/R-promoted intracellular calcium signaling, accumulation of reactive oxygen species (ROS), DNA damage, as well as NF-κB-mediated SASP secretion. Taken together, our findings demonstrate that inhibition of TGM2 contributes to bypassing I/R-induced skin keratinocyte senescence and sheds light on novel strategies against skin stresses caused by I/R.

9.
Front Immunol ; 15: 1403458, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39161767

RESUMEN

Genetic mutations in the ß-globin gene lead to a decrease or removal of the ß-globin chain, causing the build-up of unstable alpha-hemoglobin. This condition is referred to as beta-thalassemia (BT). The present treatment strategies primarily target the correction of defective erythropoiesis, with a particular emphasis on gene therapy and hematopoietic stem cell transplantation. However, the presence of inefficient erythropoiesis in BT bone marrow (BM) is likely to disturb the previously functioning BM microenvironment. This includes accumulation of various macromolecules, damage to hematopoietic function, destruction of bone cell production and damage to osteoblast(OBs), and so on. In addition, the changes of BT BM microenvironment may have a certain correlation with the occurrence of hematological malignancies. Correction of the microenvironment can be achieved through treatments such as iron chelation, antioxidants, hypoglycemia, and biologics. Hence, This review describes damage in the BT BM microenvironment and some potential remedies.


Asunto(s)
Médula Ósea , Microambiente Celular , Talasemia beta , Humanos , Médula Ósea/patología , Médula Ósea/metabolismo , Talasemia beta/terapia , Terapia Genética , Animales , Talasemia/terapia , Eritropoyesis , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Quelantes del Hierro/uso terapéutico , Globinas beta/genética
10.
FEBS J ; 2024 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-39185948

RESUMEN

Cellular senescence is described as an irreversible cell cycle arrest for proliferating cells and is associated with the secretion of senescence associated secretory phenotype factors. It has been known to accumulate with age and is regarded as a key driver of aging-associated skin pathologies. However, the lack of markers of skin senescence and partially understood skin cellular senescence mechanisms has limited the exploration of skin aging and anti-skin aging strategies. Recently, intracellular calcium signaling has emerged as an important regulator of cellular senescence and aging. However, little is known about the modulation of skin cellular senescence by calcium-associated factors. Here, we found that the expression of calcium channel transient receptor potential melastatin 7 (TRPM7) is elevated during skin keratinocyte senescence and aging. Importantly, TRPM7 promotes skin keratinocyte senescence by triggering intracellular calcium transfer from the endoplasmic reticulum to the mitochondria; accumulation of mitochondrial calcium then induces a drop in mitochondrial membrane potential and reactive oxygen species production, leading to subsequent nuclear enlargement and DNA damage. Altogether, these findings indicate that TRPM7 controls skin keratinocyte senescence through regulating intracellular calcium signaling, and thus, shed light on novel strategies for anti-skin aging therapy.

11.
Physiol Rep ; 12(14): e16037, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39034596

RESUMEN

This study assessed muscle activity (root mean square, RMS, and median frequency, MDF) to evaluate the acute response to blood flow restriction (BFR) resistance exercise (RE) and conventional moderate intensity (MI) RE. We also performed exploratory analyses of differences based on sex and exercise-induced hypoalgesia (EIH). Fourteen asymptomatic individuals performed four sets of unilateral leg press with their dominant leg to volitional fatigue under two exercise conditions: BFR RE and MI RE. Dominant side rectus femoris (RF) and vastus lateralis (VL) muscle activity were measured using surface electromyography (sEMG) through exercise. RMS and MDF were calculated and compared between conditions and timepoints using a linear mixed model. Pressure pain thresholds (PPT) were tested before and immediately after exercise and used to quantify EIH. Participants were then divided into EIH responders and nonresponders, and the differences on RMS and MDF were compared between the two groups using Hedges' g. RMS significantly increased over time (RF: p = 0.0039; VL: p = 0.001) but not between conditions (RF: p = 0.4; VL: p = 0.67). MDF decreased over time (RF: p = 0.042; VL: p < 0.001) but not between conditions (RF: p = 0.74; VL: p = 0.77). Consistently lower muscle activation was found in females compared with males (BRF, RF: g = 0.63; VL, g = 0.5. MI, RF: g = 0.72; VL: g = 1.56), with more heterogeneous findings in MDF changes. For BFR, EIH responders showed greater RMS changes (Δ RMS) (RF: g = 0.90; VL: g = 1.21) but similar MDF changes (Δ MDF) (RF: g = 0.45; VL: g = 0.28) compared to nonresponders. For MI, EIH responders demonstrated greater increase on Δ RMS (g = 0.61) and decrease on Δ MDF (g = 0.68) in RF but similar changes in VL (Δ RMS: g = 0.40; Δ MDF: g = 0.39). These results indicate that when exercising to fatigue, no statistically significant difference was observed between BFR RE and conventional MI RE in Δ RMS and Δ MDF. Lower muscle activity was noticed in females. While exercising to volitional fatigue, muscle activity may contribute to EIH.


Asunto(s)
Flujo Sanguíneo Regional , Entrenamiento de Fuerza , Humanos , Masculino , Femenino , Entrenamiento de Fuerza/métodos , Adulto , Flujo Sanguíneo Regional/fisiología , Músculo Esquelético/fisiología , Músculo Esquelético/irrigación sanguínea , Umbral del Dolor/fisiología , Electromiografía , Adulto Joven , Ejercicio Físico/fisiología
12.
Angew Chem Int Ed Engl ; 63(44): e202412020, 2024 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-38993096

RESUMEN

Mutualisms are interactions that benefit all species involved. It has been widely investigated in neighbouring subjects, such as biology, ecology, sociology, and economics. However, such a reciprocal relationship in synthetic chemical systems has rarely been studied. Here, we demonstrate a mutualistic synthesis where byproducts from two orthogonal chemical reactions aid each other's production. Disulfide exchange and hydrazone exchange were chosen to generate two dynamic combinatorial libraries. A minor tetrameric macrocycle from the active disulfide library was quantitatively amplified in the presence of the hydrazone library. This incorporation also turned on the previously inert hydrazone reaction, producing a linear species that formed a "handcuffs" catenane with the disulfide tetramer. These findings not only lend robust support to the hypothesis of "RNA-peptide coevolution" for the origin of life but also broaden the scope of synthetic chemistry, highlighting the untapped potential of minor products from different reactions. Additionally, the co-self-assembly of these mutualistic entities to form supramolecular structures opens new avenues for future development of composite nanosystems with synergistic properties.

13.
Front Genet ; 15: 1404031, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38911299

RESUMEN

The identification of genome-wide selection signatures can reveal the potential genetic mechanisms involved in the generation of new breeds through natural or artificial selection. In this study, we screened the genome-wide selection signatures of prolific Suffolk sheep, a new strain of multiparous mutton sheep, to identify candidate genes for reproduction traits and unravel the germplasm characteristics and population genetic evolution of this new strain of Suffolk sheep. Whole-genome resequencing was performed at an effective sequencing depth of 20× for genomic diversity and population structure analysis. Additionally, selection signatures were investigated in prolific Suffolk sheep, Suffolk sheep, and Hu sheep using fixation index (F ST) and heterozygosity H) analysis. A total of 5,236.338 Gb of high-quality genomic data and 28,767,952 SNPs were obtained for prolific Suffolk sheep. Moreover, 99 selection signals spanning candidate genes were identified. Twenty-three genes were significantly associated with KEGG pathway and Gene Ontology terms related to reproduction, growth, immunity, and metabolism. Through selective signal analysis, genes such as ARHGEF4, CATIP, and CCDC115 were found to be significantly correlated with reproductive traits in prolific Suffolk sheep and were highly associated with the mTOR signaling pathway, the melanogenic pathway, and the Hippo signaling pathways, among others. These results contribute to the understanding of the evolution of artificial selection in prolific Suffolk sheep and provide candidate reproduction-related genes that may be beneficial for the establishment of new sheep breeds.

14.
Angew Chem Int Ed Engl ; 63(33): e202406103, 2024 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-38818671

RESUMEN

Fundamental understanding of mechanochemical reactivity is important for designing new mechanophores. Besides the core structure of mechanophores, substituents on a mechanophore can affect its mechanochemical reactivity through electronic stabilization of the intermediate or effectiveness of force transduction from the polymer backbone to the mechanophore. The latter factor represents a unique mechanical effect in considering polymer mechanochemistry. Here, we show that regioisomeric linkage that is not directly adjacent to the first cleaving bond in cyclobutane can still significantly affect the mechanochemical reactivity of the mechanophore. We synthesized three non-scissile 1,2-diphenyl cyclobutanes, varying their linkage to the polymer backbone via the o, m, or p-position of the diphenyl substituents. Even though the regioisomers share the same substituted cyclobutane core structure and similar electronic stabilization of the diradical intermediate from cleaving the first C-C bond, the p isomer exhibited significantly higher mechanochemical reactivity than the o and m isomers. The observed difference in reactivity can be rationalized as the much more effective force transduction to the scissile bond through the p-position than the other two substitution positions. These findings point to the importance of considering force-bearing linkages that are more distant from the bond to be cleaved when incorporating mechanophores into polymer backbones.

15.
Molecules ; 29(9)2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38731397

RESUMEN

A chemical investigation of the arils of Torreya grandis led to the isolation of seven abietane-type diterpenoids (compounds 1-7) including three previously undescribed compounds, one unreported natural product, and three known analogs. The structures of these compounds were determined by means of spectroscopy, single-crystal X-ray diffraction, and ECD spectra. An antibacterial activity assay showed that compounds 5 and 6 had significant inhibitory effects on methicillin-resistant Staphylococcus aureus, with MIC values of 100 µM. Moreover, compounds 1, 3, 4, and 7 exhibited anti-neuroinflammatory activity in LPS-stimulated BV-2 microglia cells, with the IC50 values ranging from 38.4 to 67.9 µM.


Asunto(s)
Abietanos , Antibacterianos , Abietanos/química , Abietanos/farmacología , Antibacterianos/farmacología , Antibacterianos/química , Pruebas de Sensibilidad Microbiana , Microglía/efectos de los fármacos , Microglía/metabolismo , Ratones , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Animales , Estructura Molecular , Línea Celular , Antiinflamatorios/farmacología , Antiinflamatorios/química , Extractos Vegetales/química , Extractos Vegetales/farmacología , Diterpenos/farmacología , Diterpenos/química , Diterpenos/aislamiento & purificación , Lipopolisacáridos/farmacología
16.
Vaccines (Basel) ; 12(5)2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38793715

RESUMEN

The rapid mutation of SARS-CoV-2 has led to multiple rounds of large-scale breakthrough infection and reinfection worldwide. However, the dynamic changes of humoral and cellular immunity responses to several subvariants after infection remain unclear. In our study, a 6-month longitudinal immune response evaluation was conducted on 118 sera and 50 PBMC samples from 49 healthy individuals who experienced BA.5/BF.7/XBB breakthrough infection or BA.5/BF.7-XBB reinfection. By studying antibody response, memory B cell, and IFN-γ secreting CD4+/CD8+ T cell response to several SARS-CoV-2 variants, we observed that each component of immune response exhibited distinct kinetics. Either BA.5/BF.7/XBB breakthrough infection or BA.5/BF.7-XBB reinfection induces relatively high level of binding and neutralizing antibody titers against Omicron subvariants at an early time point, which rapidly decreases over time. Most of the individuals at 6 months post-breakthrough infection completely lost their neutralizing activities against BQ.1.1, CH.1.1, BA.2.86, JN.1 and XBB subvariants. Individuals with BA.5/BF.7-XBB reinfection exhibit immune imprinting shifting and recall pre-existing BA.5/BF.7 neutralization antibodies. In the BA.5 breakthrough infection group, the frequency of BA.5 and XBB.1.16-RBD specific memory B cells, resting memory B cells, and intermediate memory B cells gradually increased over time. On the other hand, the frequency of IFN-γ secreting CD4+/CD8+ T cells induced by WT/BA.5/XBB.1.16 spike trimer remains stable over time. Overall, our research indicates that individuals with breakthrough infection have rapidly declining antibody levels but have a relatively stable cellular immunity that can provide some degree of protection from future exposure to new antigens.

17.
BMC Med Imaging ; 24(1): 114, 2024 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-38760689

RESUMEN

Digital dental technology covers oral cone-beam computed tomography (CBCT) image processing and low-dose CBCT dental applications. A low-dose CBCT image enhancement method based on image fusion is proposed to address the need for subzygomatic small screw insertion. Specifically, firstly, a sharpening correction module is proposed, where the CBCT image is sharpened to compensate for the loss of details in the underexposed/over-exposed region. Secondly, a visibility restoration module based on type II fuzzy sets is designed, and a contrast enhancement module using curve transformation is designed. In addition to this, we propose a perceptual fusion module that fuses visibility and contrast of oral CBCT images. As a result, the problems of overexposure/underexposure, low visibility, and low contrast that occur in oral CBCT images can be effectively addressed with consistent interpretability. The proposed algorithm was analyzed in comparison experiments with a variety of algorithms, as well as ablation experiments. After analysis, compared with advanced enhancement algorithms, this algorithm achieved excellent results in low-dose CBCT enhancement and effective observation of subzygomatic small screw implantation. Compared with the best performing method, the evaluation metric is 0.07-2 higher on both datasets. The project can be found at: https://github.com/sunpeipei2024/low-dose-CBCT .


Asunto(s)
Algoritmos , Tornillos Óseos , Tomografía Computarizada de Haz Cónico , Humanos , Tomografía Computarizada de Haz Cónico/métodos , Cigoma/diagnóstico por imagen , Dosis de Radiación , Procesamiento de Imagen Asistido por Computador/métodos , Intensificación de Imagen Radiográfica/métodos
18.
Mol Neurobiol ; 2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38717559

RESUMEN

Systemic inflammatory stimulus is a risk factor for the incidence of ischemic stroke and contributes to poorer clinical outcomes. Solute carrier 15A3 (SLC15A3) is a peptide/histidine transporter that is implicated in regulating inflammatory responses. However, whether SLC15A3 affects the progression of ischemic stroke associated with systemic inflammation is unclear. The transient middle cerebral artery occlusion (tMCAO) mice with LPS administration (LPS/tMCAO) were prepared as an in vivo model, and LPS-induced BV2 cells under oxygen-glucose deprivation (OGD) exposure were utilized as an in vitro model. We found that SLC15A3 was highly expressed in the ischemic penumbra of LPS/tMCAO mice, and its inhibition reduced infarct area, attenuated neurological deficit, recovered motor function, and mitigated apoptotic neurons. Knockdown of SLC15A3 suppressed the proinflammatory M1-type markers and promoted the levels of M2-associated genes. The in vitro results confirmed that SLC15A3 overexpression promoted microglia polarizing towards M1 subtypes, while SLC15A3 inhibition exerted an opposite effect. In addition, we demonstrated that the p65 signaling pathway and HIF1α were activated by LPS/OGD. Luciferase reporter assay showed that inhibiting p65 using its specific inhibitor BAY 11-7082 or silencing HIF1α using siRNAs reduced the transcriptional activity of SLC15A3 in LPS/OGD-induced BV2 cells. Results in NIH 3T3 cells also confirmed that p65 and HIF1α directly bound to the SLC15A3 promoter to activate SLC15A3 transcription. In conclusion, this work shows that SLC15A3, transcriptionally activated by p65 and HIF1α, contributes to poor outcomes in ischemic stroke associated with systemic inflammation by promoting microglial cells polarizing towards M1 types.

19.
Nanoscale ; 16(19): 9406-9411, 2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38629905

RESUMEN

In the field of contemporary medicine, inflammation has emerged as a significant concern in global public health. Among the current anti-inflammatory strategies, nanozymes possess distinctive advantages and demonstrate unexpected efficacy in combating inflammation. However, the indeterminate structures and limited enzyme-like activity exhibited by most developed nanozymes impede their clinical translation and therapeutic effectiveness. In this paper, we developed a nanozyme derived from a well-defined metal-organic cage (MOC). The oxidized MOC (MOC-O), containing pyridine nitrogen oxide moieties, exhibited effective cascade superoxide dismutase (SOD) and catalase (CAT)-like activities for scavenging reactive oxygen species (ROS). This ROS scavenging ability was confirmed through flow cytometry analysis using DCFH-DA in a hypoxia/reoxygenation (H/R) model, where MOC-O significantly alleviated oxidative stress. Furthermore, the administration of MOC-O resulted in preserved renal function during renal ischemia-reperfusion (I/R) injury due to downregulated oxidative stress levels and reduced cell apoptosis.


Asunto(s)
Antioxidantes , Riñón , Estrés Oxidativo , Especies Reactivas de Oxígeno , Daño por Reperfusión , Superóxido Dismutasa , Daño por Reperfusión/metabolismo , Daño por Reperfusión/tratamiento farmacológico , Daño por Reperfusión/patología , Animales , Antioxidantes/química , Antioxidantes/farmacología , Especies Reactivas de Oxígeno/metabolismo , Riñón/metabolismo , Estrés Oxidativo/efectos de los fármacos , Superóxido Dismutasa/metabolismo , Ratones , Apoptosis/efectos de los fármacos , Catalasa/metabolismo , Estructuras Metalorgánicas/química , Estructuras Metalorgánicas/farmacología , Masculino
20.
Int J Sports Med ; 45(11): 810-819, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-38588713

RESUMEN

We compared the magnitude of exercise-induced hypoalgesia and conditioned pain modulation between blood-flow restriction (BFR) resistance exercise (RE) and moderate-intensity RE. Twenty-five asymptomatic participants performed unilateral leg press in two visits. For moderate-intensity RE, subjects exercised at 50% 1RM without BFR, whereas BFR RE exercised at 30% 1RM with a cuff inflated to 60% limb occlusion pressure. Exercise-induced hypoalgesia was quantified by pressure pain threshold changes before and after RE. Conditioned pain modulation was tested using cold water as the conditioning stimulus and mechanical pressure as the test stimulus and quantified as pressure pain threshold change. Difference in conditioned pain modulation pre- to post-RE was then calculated. The differences of RE on pain modulations were compared using paired t-tests. Pearson's r was used to examine the correlation between exercise-induced hypoalgesia and changes in conditioned pain modulation. We found greater hypoalgesia with BFR RE compared to moderate-intensity RE (p=0.008). Significant moderate correlations were found between exercise-induced hypoalgesia and changes in conditioned pain modulation (BFR: r=0.63, moderate-intensity: r=0.72). BFR RE has favorable effects on pain modulation in healthy adults and the magnitude of exercise-induced hypoalgesia is positively correlated with conditioned pain modulation activation.


Asunto(s)
Umbral del Dolor , Flujo Sanguíneo Regional , Entrenamiento de Fuerza , Humanos , Entrenamiento de Fuerza/métodos , Umbral del Dolor/fisiología , Masculino , Femenino , Adulto Joven , Adulto , Flujo Sanguíneo Regional/fisiología , Dolor
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