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1.
J Oral Rehabil ; 2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38845181

RESUMEN

BACKGROUND: There is limited knowledge about the impact of painful temporomandibular disorders (TMDs) and pain characteristics on jaw functional limitation and oral health-related quality of life (OHRQoL) in TMD patients. OBJECTIVES: The influence of painful TMDs and pain characteristics on jaw functional limitation and OHRQoL was investigated. Inter-relationships between limitation in jaw function and various OHRQoL domains, along with facial pain attributes predicting impaired jaw function and diminished OHRQoL were also examined. METHODS: TMD patients were recruited from a university-based hospital. A comprehensive questionnaire comprising demographic variables, the DC/TMD Symptom Questionnaire, Graded Chronic Pain Scale, Jaw Functional Limitation Scale-8 (JFLS-8) and Oral Health Impact Profile-TMD (OHIP-TMD) was administered. Participants underwent a protocolized physical examination, and TMD diagnoses were determined utilising the DC/TMD algorithms. Participants were subsequently stratified into intra-articular/pain-related/combined TMD groups, as well as no TMD pain, acute/chronic pain and low/high-intensity pain groups. Data were assessed using non-parametric and hierarchical linear regression analyses (α = .05). RESULTS: The final sample consisted of 280 participants (mean age 31.2 (SD 11.8) years; 79.3% women). Significant differences in pain characteristics, JFLS-8, and global OHIP scores were observed across the various TMD subtypes, pain chronicity and pain intensity categories. Pain intensity and pain-related interference exhibited moderate correlations with JFLS-8 and global OHIP scores (rs = 0.53-0.60). Moderate associations were also noted between JFLS-8 and global OHIP, as well as most OHIP domains (rs = 0.42-0.64). Both jaw functional limitation and OHRQoL were predicted by sex, pain intensity and pain-related interference. CONCLUSIONS: Sex, pain intensity and pain-related interference are key determinants for both impaired jaw function and diminished OHRQoL, with pain-related interference exerting a more pronounced effect.

2.
J Phys Chem Lett ; : 6126-6136, 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38830203

RESUMEN

The recently developed Quasiparticle Energy (QE) scheme, based on a DFT calculation with one more (or less) electron, offers a good description of excitation energies, even with charge transfer characters. In this work, QE is further extended to calculate electron transfer (ET) couplings involving two excited states. We tested it with a donor-acceptor complex, consisting of a furan and a 1,1-dicyanoethylene (DCNE), in which two low lying charge transfer and local excitation states are involved. With generalized Mülliken-Hush and fragment charge-difference schemes, couplings from the QE approach generally agree well with those obtained from TDDFT, except that QE couplings exhibit better exponential distance dependence. Couplings from half-energy gaps with an external field are also calculated and reported. Our results show that the QE scheme is robust in calculating ET couplings with greatly reduced computational time.

3.
Artículo en Inglés | MEDLINE | ID: mdl-38815255

RESUMEN

Currently, glycopeptide quantitation is mainly based on relative quantitation due to absolute quantitation requiring isotope-labeled or standard glycopeptides which may not be commercially available or are very costly and time consuming to synthesize. To address this grand challenge, coulometric mass spectrometry (CMS), based on the combination of electrochemistry (EC) and mass spectrometry (MS), was utilized to quantify electrochemically active glycopeptides without the need of using standard materials. In this study, we studied tyrosine-containing glycopeptides, NYIVGQPSS(ß-GlcNAc)TGNL-OH and NYSVPSS(ß-GlcNAc)TGNL-OH, and successfully quantified them directly with CMS with a discrepancy of less than 5% between the CMS measured amount and the theoretical amount. Taking one step further, we applied this approach to quantify glycopeptides generated from the digestion of NIST mAb, a monoclonal antibody reference material. Through HILIC column separation, five N297 glycopeptides resulting from NIST mAb tryptic digestion were successfully separated and quantified by CMS for an absolute amount without the use of any standard materials. This study indicates the potential utility of CMS for quantitative proteomics research.

4.
J Reconstr Microsurg ; 2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38710224

RESUMEN

BACKGROUND: Speech restoration is important for communication and social activities after pharyngolaryngectomy in head and neck cancer or corrosive injury. Several techniques of voice restoration have been developed to improve life quality. The aim of this paper was to focus on the microsurgical transfer of ileocolon flap and outcome of further voice rehabilitation. PATIENTS AND METHODS: From 2010 to 2022, 69 patients had ileocolon flap at our hospital with postoperative speech training and regular follow-up for over 1 year. The patients received deglutition training first, followed by voice rehabilitation. Voice outcomes were evaluated at an interval of 3 months and finally at 12 months of voice training rehabilitation. Among other examinations, the speech function was evaluated using a 4-point Likert scale and senior surgeon (H-c.C.) scoring system. RESULTS: The results showed that speech function reached 13.1% of excellent voice, 65.1% of good voice, 13.1% of fair result, and 8.7% of poor result by Likert scales. Meanwhile, the senior surgeon (H-c.C.) score showed 17.4% of excellent, 63.8% of moderate, and 18.8% of poor results. About voice laboratory results, maximal phonation time was 11.0 seconds, and the average number counted in one breath was 15. Loudness and frequency showed 56.0 dB and 105.0 Hz, respectively. CONCLUSION: The study showed that after voice reconstruction with ileocolon flap followed by the voice rehabilitation program, the patients would have a better understanding of the altered anatomical structures and practice in a more efficient way. Adequate recommendation by the therapists to plastic surgeons for revision surgeries optimized voice function of the patients.

5.
Artículo en Inglés | MEDLINE | ID: mdl-38619962

RESUMEN

Graph convolutional networks (GCNs) have been widely used in skeleton-based action recognition. However, existing approaches are limited in fine-grained action recognition due to the similarity of interclass data. Moreover, the noisy data from pose extraction increase the challenge of fine-grained recognition. In this work, we propose a flexible attention block called channel-variable spatial-temporal attention (CVSTA) to enhance the discriminative power of spatial-temporal joints and obtain a more compact intraclass feature distribution. Based on CVSTA, we construct a multidimensional refinement GCN (MDR-GCN) that can improve the discrimination among channel-, joint-, and frame-level features for fine-grained actions. Furthermore, we propose a robust decouple loss (RDL) that significantly boosts the effect of the CVSTA and reduces the impact of noise. The proposed method combining MDR-GCN with RDL outperforms the known state-of-the-art skeleton-based approaches on fine-grained datasets, FineGym99 and FSD-10, and also on the coarse NTU-RGB + D 120 dataset and NTU-RGB + D X-view version. Our code is publicly available at https://github.com/dingyn-Reno/MDR-GCN.

6.
Int J Biol Macromol ; 268(Pt 1): 131696, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38642679

RESUMEN

Carbon­carbon (C-C) bonds serve as the fundamental structural backbone of organic molecules. As a critical CC bond forming enzyme, α-oxoamine synthase is responsible for the synthesis of α-amino ketones by performing the condensation reaction between amino acids and acyl-CoAs. We previously identified an α-oxoamine synthase (AOS), named as Alb29, involved in albogrisin biosynthesis in Streptomyces albogriseolus MGR072. This enzyme belongs to the α-oxoamine synthase family, a subfamily under the pyridoxal 5'-phosphate (PLP) dependent enzyme superfamily. In this study, we report the crystal structures of Alb29 bound to PLP and L-Glu, which provide the atomic-level structural insights into the substrate recognition by Alb29. We discover that Alb29 can catalyze the amino transformation from L-Gln to L-Glu, besides the condensation of L-Glu with ß-methylcrotonyl coenzyme A. Subsequent structural analysis has revealed that one flexible loop in Alb29 plays an important role in both amino transformation and condensation. Based on the crystal structure of the S87G mutant in the loop region, we capture two distinct conformations of the flexible loop in the active site, compared with the wild-type Alb29. Our study offers valuable insights into the catalytic mechanism underlying substrate recognition of Alb29.


Asunto(s)
Ácido Glutámico , Especificidad por Sustrato , Ácido Glutámico/química , Modelos Moleculares , Streptomyces/enzimología , Cristalografía por Rayos X , Dominio Catalítico , Conformación Proteica , Fosfato de Piridoxal/metabolismo , Fosfato de Piridoxal/química , Proteínas Bacterianas/química , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/genética , Relación Estructura-Actividad
7.
Biomed J ; : 100727, 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38636898

RESUMEN

BACKGROUND: We investigated the effects of combination therapy albendazole and doxycycline in Angiostrongylus cantonensis-infected mice during early and late treatment. MATERIALS AND METHODS: C57BL/6 and BALB/c mice were divided into five groups: (i) uninfected, (ii) infected with A. cantonensis, (iii) infected + 10 mg/kg albendazole, (iv) infected + 25mg/kg doxycycline, and (v) infected + 10 mg/kg albendazole + 25 mg/kg doxycycline. We administered drugs in both early treatments started at 7-day post infections (dpi) and late treatments (14 dpi) to A. cantonensis-infected C57BL/6 and BALB/c mice. To assess the impact of these treatments, we employed the Morris water maze test to evaluate spatial learning and memory abilities, and the rotarod test to measure motor coordination and balance in C57BL/6 mice. Additionally, we monitored the expression of the cytokine IL-33 and GFAP in the brain of these mice using western blot analysis. RESULTS: In this study, A. cantonensis infection was observed to cause extensive cerebral angiostrongyliasis in C57BL/6 mice. This condition significantly affected their spatial learning and memory abilities, as assessed by the Morris water maze test, as well as their motor coordination, which was evaluated using the rotarod test. Early treatment with albendazole led to favorable recovery outcomes. Both C57BL/6 and BALB/c mice express IL-33 and GFAP after co-therapy. The differences of levels and patterns of IL-33 and GFAP expression in mice may be influenced by the balance between pro-inflammatory and anti-inflammatory signals within the immune system. CONCLUSIONS: Combination therapy with anthelmintics and antibiotics in the early stage of A. cantonensis infection, in C57BL/6 and BALB/c mice resulted in the death of parasites in the brain and reduced the subsequent neural function damage and slowed brain damage and neurobehavior impairment. This study suggests a more effective and novel treatment, and drug delivery method for brain lesions that can decrease the neurological damage of angiostrongyliasis patients.

9.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 46(2): 147-153, 2024 Apr.
Artículo en Chino | MEDLINE | ID: mdl-38686709

RESUMEN

Objective To screen out the biomarkers linked to prognosis of breast invasive carcinoma based on the analysis of transcriptome data by random forest (RF),extreme gradient boosting (XGBoost),light gradient boosting machine (LightGBM),and categorical boosting (CatBoost). Methods We obtained the expression data of breast invasive carcinoma from The Cancer Genome Atlas and employed DESeq2,t-test,and Cox univariate analysis to identify the differentially expressed protein-coding genes associated with survival prognosis in human breast invasive carcinoma samples.Furthermore,RF,XGBoost,LightGBM,and CatBoost models were established to mine the protein-coding gene markers related to the prognosis of breast invasive cancer and the model performance was compared.The expression data of breast cancer from the Gene Expression Omnibus was used for validation. Results A total of 151 differentially expressed protein-coding genes related to survival prognosis were screened out.The machine learning model established with C3orf80,UGP2,and SPC25 demonstrated the best performance. Conclusions Three protein-coding genes (UGP2,C3orf80,and SPC25) were screened out to identify breast invasive carcinoma.This study provides a new direction for the treatment and diagnosis of breast invasive carcinoma.


Asunto(s)
Biomarcadores de Tumor , Neoplasias de la Mama , Aprendizaje Automático , Humanos , Neoplasias de la Mama/genética , Femenino , Biomarcadores de Tumor/genética , Pronóstico , Perfilación de la Expresión Génica
10.
Curr Med Sci ; 44(2): 346-354, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38517672

RESUMEN

OBJECTIVE: While the reduction of transient receptor potential channel subfamily M member 5 (TRPM5) has been reported in islet cells from type 2 diabetic (T2D) mouse models, its role in lipotoxicity-induced pancreatic ß-cell dysfunction remains unclear. This study aims to study its role. METHODS: Pancreas slices were prepared from mice subjected to a high-fat-diet (HFD) at different time points, and TRPM5 expression in the pancreatic ß cells was examined using immunofluorescence staining. Glucose-stimulated insulin secretion (GSIS) defects caused by lipotoxicity were mimicked by saturated fatty acid palmitate (Palm). Primary mouse islets and mouse insulinoma MIN6 cells were treated with Palm, and the TRPM5 expression was detected using qRT-PCR and Western blotting. Palm-induced GSIS defects were measured following siRNA-based Trpm5 knockdown. The detrimental effects of Palm on primary mouse islets were also assessed after overexpressing Trpm5 via an adenovirus-derived Trpm5 (Ad-Trpm5). RESULTS: HFD feeding decreased the mRNA levels and protein expression of TRPM5 in mouse pancreatic islets. Palm reduced TRPM5 protein expression in a time- and dose-dependent manner in MIN6 cells. Palm also inhibited TRPM5 expression in primary mouse islets. Knockdown of Trpm5 inhibited insulin secretion upon high glucose stimulation but had little effect on insulin biosynthesis. Overexpression of Trpm5 reversed Palm-induced GSIS defects and the production of functional maturation molecules unique to ß cells. CONCLUSION: Our findings suggest that lipotoxicity inhibits TRPM5 expression in pancreatic ß cells both in vivo and in vitro and, in turn, drives ß-cell dysfunction.


Asunto(s)
Células Secretoras de Insulina , Islotes Pancreáticos , Ratones , Animales , Células Secretoras de Insulina/metabolismo , Islotes Pancreáticos/metabolismo , Insulina/metabolismo , Glucosa/farmacología , Glucosa/metabolismo , Secreción de Insulina
11.
J Dent ; 144: 104931, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38458378

RESUMEN

OBJECTIVES: To develop a deep learning-based system for precise, robust, and fully automated segmentation of the mandibular canal on cone beam computed tomography (CBCT) images. METHODS: The system was developed on 536 CBCT scans (training set: 376, validation set: 80, testing set: 80) from one center and validated on an external dataset of 89 CBCT scans from 3 centers. Each scan was annotated using a multi-stage annotation method and refined by oral and maxillofacial radiologists. We proposed a three-step strategy for the mandibular canal segmentation: extraction of the region of interest based on 2D U-Net, global segmentation of the mandibular canal, and segmentation refinement based on 3D U-Net. RESULTS: The system consistently achieved accurate mandibular canal segmentation in the internal set (Dice similarity coefficient [DSC], 0.952; intersection over union [IoU], 0.912; average symmetric surface distance [ASSD], 0.046 mm; 95% Hausdorff distance [HD95], 0.325 mm) and the external set (DSC, 0.960; IoU, 0.924; ASSD, 0.040 mm; HD95, 0.288 mm). CONCLUSIONS: These results demonstrated the potential clinical application of this AI system in facilitating clinical workflows related to mandibular canal localization. CLINICAL SIGNIFICANCE: Accurate delineation of the mandibular canal on CBCT images is critical for implant placement, mandibular third molar extraction, and orthognathic surgery. This AI system enables accurate segmentation across different models, which could contribute to more efficient and precise dental automation systems.


Asunto(s)
Tomografía Computarizada de Haz Cónico , Imagenología Tridimensional , Mandíbula , Tomografía Computarizada de Haz Cónico/métodos , Humanos , Mandíbula/diagnóstico por imagen , Mandíbula/anatomía & histología , Imagenología Tridimensional/métodos , Aprendizaje Profundo , Procesamiento de Imagen Asistido por Computador/métodos
12.
Adv Sci (Weinh) ; 11(19): e2308582, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38477538

RESUMEN

Heterojunctions in electrode materials offer diverse improvements during the cycling process of energy storage devices, such as volume change buffering, accelerated ion/electron transfer, and better electrode structure integrity, however, obtaining optimal heterostructures with nanoscale domains remains challenging within constrained materials. A novel in situ electrochemical method is introduced to develop a reversible CuSe/PSe p-n heterojunction (CPS-h) from Cu3PSe4 as starting material, targeting maximum stability in potassium ion storage. The CPS-h formation is thermodynamically favorable, characterized by its superior reversibility, minimized diffusion barriers, and enhanced conversion post K+ interaction. Within CPS-h, the synergy of the intrinsic electric field and P-Se bonds enhance electrode stability, effectively countering the Se shuttling phenomenon. The specific orientation between CuSe and PSe leads to a 35° lattice mismatch generates large space at the interface, promoting efficient K ion migration. The Mott-Schottky analysis validates the consistent reversibility of CPS-h, underlining its electrochemical reliability. Notably, CPS-h demonstrates a negligible 0.005% capacity reduction over 10,000 half-cell cycles and remains stable through 2,000 and 4,000 cycles in full cells and hybrid capacitors, respectively. This study emphasizes the pivotal role of electrochemical dynamics in formulating highly stable p-n heterojunctions, representing a significant advancement in potassium-ion battery (PIB) electrode engineering.

13.
Eye Vis (Lond) ; 11(1): 10, 2024 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-38448961

RESUMEN

Artificial intelligence (AI) is an emerging field which could make an intelligent healthcare model a reality and has been garnering traction in the field of medicine, with promising results. There have been recent developments in machine learning and/or deep learning algorithms for applications in ophthalmology-primarily for diabetic retinopathy, and age-related macular degeneration. However, AI research in the field of cornea diseases is relatively new. Algorithms have been described to assist clinicians in diagnosis or detection of cornea conditions such as keratoconus, infectious keratitis and dry eye disease. AI may also be used for segmentation and analysis of cornea imaging or tomography as an adjunctive tool. Despite the potential advantages that these new technologies offer, there are challenges that need to be addressed before they can be integrated into clinical practice. In this review, we aim to summarize current literature and provide an update regarding recent advances in AI technologies pertaining to corneal diseases, and its potential future application, in particular pertaining to image analysis.

14.
J Am Chem Soc ; 146(12): 8706-8715, 2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38487838

RESUMEN

Metal nanoclusters (MNCs) represent a promising class of materials for catalytic carbon dioxide and proton reduction as well as dihydrogen oxidation. In such reactions, multiple proton-coupled electron transfer (PCET) processes are typically involved, and the current understanding of PCET mechanisms in MNCs has primarily focused on the sequential transfer mode. However, a concerted transfer pathway, i.e., concerted electron-proton transfer (CEPT), despite its potential for a higher catalytic rate and lower reaction barrier, still lacks comprehensive elucidation. Herein, we introduce an experimental paradigm to test the feasibility of the CEPT process in MNCs, by employing Au18(SR)14 (SR denotes thiolate ligand), Au22(SR)18, and Au25(SR)18- as model clusters. Detailed investigations indicate that the photoinduced PCET reactions in the designed system proceed via an CEPT pathway. Furthermore, the rate constants of gold nanoclusters (AuNCs) have been found to be correlated with both the size of the cluster and the flexibility of the Au-S framework. This newly identified PCET behavior in AuNCs is prominently different from that observed in semiconductor quantum dots and plasmonic metal nanoparticles. Our findings are of crucial importance for unveiling the catalytic mechanisms of quantum-confined metal nanomaterials and for the future rational design of more efficient catalysts.

15.
Int Ophthalmol ; 44(1): 81, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38358400

RESUMEN

BACKGROUND: The main treatment for the symptoms of proptosis and optic nerve compression caused by thyroid-associated ophthalmopathy is orbital decompression surgery. Medial inferior wall decompression and balanced decompression are two frequently used surgical procedures. However, there is no unified consensus on how to choose different surgical options for orbital decompression in clinical practice. AIMS: To compare the effects of medial inferior wall decompression and balanced decompression surgery through meta-analysis and to provide reference for clinical optimal decision making. METHODS: Databases, including PubMed, Web of Science, Ovid, Cochrane Library, and ClinicalTrials.gov, were searched for randomized controlled trials and cohort studies on decompression surgery for thyroid-associated ophthalmopathy published from inception to March 21, 2023. Using RevMan 5.3 software, a meta-analysis was conducted based on the following outcome indicators: proptosis, diplopia rate, intraocular pressure, visual acuity, and complication rate. RESULTS: Two randomized controlled trials and five cohort studies with a total of 377 patients were included in this analysis. After balanced decompression surgery, patients with thyroid-associated ophthalmopathy experienced a significant decrease in proptosis [MD = 4.92, 95% CI (4.26, 5.58), P < 0.0001]. Balanced decompression can improve postoperative visual acuity [MD = - 0.35, 95% CI (- 0.56, - 0.13), P = 0.001] and intraocular pressure [MD = 5.33, 95% CI (3.34, 7.32), P < 0.0001]. The rates of proptosis [MD = 0.33, 95% CI (- 1.80, 2.46), P = 0.76] and diplopia [OR = 1.20, 95% CI (0.38, 3.76), P = 0.76] did not differ between patients who underwent medial inferior wall decompression and those who underwent balanced decompression. CONCLUSION: Balanced decompression and medial inferior wall decompression are both effective options for surgical treatment of thyroid-associated ophthalmopathy in clinical practice.


Asunto(s)
Exoftalmia , Oftalmopatía de Graves , Humanos , Oftalmopatía de Graves/cirugía , Diplopía , Procedimientos Quirúrgicos Oftalmológicos , Descompresión , Ensayos Clínicos Controlados Aleatorios como Asunto
16.
Cranio ; : 1-10, 2024 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-38369853

RESUMEN

OBJECTIVES: The pattern of age distribution in East Asian temporomandibular disorder (TMD) patients and age-related differences in DC/TMD diagnostic subtypes/categories were evaluated. SUBJECTS AND METHODS: TMD patients from two University-based centers in China and South Korea were enrolled. Axis I physical diagnoses were rendered according to DC/TMD. Patients were categorized into six age groups (15-24, 25-34, 35-44, 45-54, 55-64, and 65-84 years; Groups A-F respectively). RESULTS: Youths/young adults (Groups A-C) formed 74.1% of TMD patients. TMJ disc displacements (74.9%), arthralgia (49.2%), and degenerative joint disease [DJD] (36.8%) were the most common TMD subtypes. The majority had combined (54.0%) and chronic (58.5%) TMDs. Youths/young adults and middle-aged/old adults had substantially lower frequencies of merely pain-related (6.2-14.5%) and intra-articular (13.8-16.8%) TMDs correspondingly. "Being female" increased the prospects of pain-related/combined TMDs by 96%/49%, respectively. CONCLUSIONS: East Asian TMD patients comprised mostly of youths/young adults who had an alarmingly high prevalence of TMJ DJD.

17.
J Dent Sci ; 19(1): 648-651, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38303838

RESUMEN

Traditionally, patients are positioned in the prone position to access the donor site during the posterior iliac bone graft harvesting procedure. However, this well-established method is associated with complications such as pressure injuries, displacement of the endotracheal tube and intravenous catheter, and blindness. Moreover, the process of turning patients 180° between the supine and prone positions is both laborious and time consuming. However, no updates have been made in the approaches published in the literature to counteract these problems. Therefore, to overcome these challenges and improve patient outcomes, we proposed a pivotal modification: change prone position to the lateral decubitus position. This approach allowed us to effectively avoid the aforementioned complications. In addition, this modification offered significant advantages, including ease of implementation and timesaving benefits. The article presented results of the modification and a comprehensive evaluation of clinical and anesthetic considerations comparing the two methods.

18.
J Mech Behav Biomed Mater ; 152: 106449, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38387118

RESUMEN

Metal alloy microstructure plays a crucial role in corrosion associated with total hip replacement (THR). THR is a prominent strategy that uses metal implants such as cobalt-chromium-molybdenum (CoCrMo) alloys due to their advantageous biological and mechanical properties. Despite all benefits, these implants undergo corrosion and wear processes in-vivo in a synergistic manner called tribocorrosion. Also, the implant retrieval findings reported that fretting corrosion occurred in-vivo, evidenced by the damage patterns that appeared on the THR junction interfaces. There is no scientific data on the studies reporting the fretting corrosion patterns of CoCrMo microstructures in the presence of specific biological treatments to date. In the current study, Flat-on-flat fretting corrosion set-up was customized and used to study the tribocorrosion patterns of fretting corrosion to understand the role of alloy microstructure. Alloy microstructural differences were created with the implant stock metal's longitudinal and transverse cutting orientations. As a result, the transverse created the non-banded, homogenous microstructure, whereas the longitudinal cut resulted in the banded, non-homogenous microstructure on the surface of the alloy (in this manuscript, the terms homogenous and banded were used). The induced currents were monitored using a three-electrode system. Three different types of electrolytes were utilized to study the fretting corrosion patterns with both homogeneous and banded microstructures: 1. Control media 2. Spent media (the macrophage cell cultured media) 3. Challenged media (media collected after the macrophage was treated with CoCrMo particles). From the electrochemical results, in the potentiostat conditions, the banded group exhibited a higher induced current in both challenged and spent electrolyte environments than in control due to the synergistic activity of CoCrMo particles and macrophage demonstrating more corrosion loss. Additionally, both Bode and Nyquist plots reported a clear difference between the banded and homogeneous microstructure, especially with challenged electrolytes becoming more corrosion-resistant post-fretting than pre-fretting results. The banded microstructure showed a unique shape of the fretting loop, which may be due to tribochemical reactions. Therefore, from the electrochemical, mechanical, and surface analysis data results, the transverse/homogenous/non-banded alloy microstructure groups show a higher resistance to fretting-corrosion damage.


Asunto(s)
Artroplastia de Reemplazo de Cadera , Prótesis de Cadera , Corrosión , Aleaciones , Cromo , Cobalto , Molibdeno , Electrólitos
19.
Commun Biol ; 7(1): 114, 2024 01 19.
Artículo en Inglés | MEDLINE | ID: mdl-38242964

RESUMEN

The naturally occurring bisexual cone of gymnosperms has long been considered a possible intermediate stage in the origin of flowers, but the mechanisms governing bisexual cone formation remain largely elusive. Here, we employed transcriptomic and DNA methylomic analyses, together with hormone measurement, to investigate the molecular mechanisms underlying bisexual cone development in the conifer Picea crassifolia. Our study reveals a "bisexual" expression profile in bisexual cones, especially in expression patterns of B-class, C-class and LEAFY genes, supporting the out of male model. GGM7 could be essential for initiating bisexual cones. DNA methylation reconfiguration in bisexual cones affects the expression of key genes in cone development, including PcDAL12, PcDAL10, PcNEEDLY, and PcHDG5. Auxin likely plays an important role in the development of female structures of bisexual cones. This study unveils the potential mechanisms responsible for bisexual cone formation in conifers and may shed light on the evolution of bisexuality.


Asunto(s)
Picea , Minorías Sexuales y de Género , Tracheophyta , Humanos , Filogenia , Bisexualidad , Picea/genética , Picea/metabolismo , Metilación de ADN , Tracheophyta/genética
20.
Artículo en Inglés | MEDLINE | ID: mdl-38289452

RESUMEN

Myocardial ischemia reperfusion injury (MIRI) represents a prevalent and severe cardiovascular condition that arises primarily after myocardial infarction recanalization, cardiopulmonary bypass surgery, and both stable and unstable angina pectoris. MIRI can induce malignant arrhythmias and heart failure, thereby increasing the morbidity and mortality rates associated with cardiovascular diseases. Hence, it is important to assess the potential pathological mechanisms of MIRI and develop effective treatments. The role of circular RNAs (circRNAs) in MIRI has increasingly become a topic of interest in recent years. Moreover, significant evidence suggests that circRNAs play a critical role in MIRI pathogenesis, thereby representing a promising therapeutic target. This review aimed to provide a comprehensive overview of the current understanding of the role of circRNAs in MIRI and discuss the mechanisms through which circRNAs contribute to MIRI development and progression, including their effects on apoptosis, inflammation, oxidative stress, and autophagy. Furthermore, the potential therapeutic applications of circRNAs in MIRI treatment, including the use of circRNA-based therapies and modulation of circRNA expression levels, have been explored. Overall, this paper highlights the importance of circRNAs in MIRI and underscores their potential as novel therapeutic targets.

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