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1.
Heliyon ; 10(11): e32616, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38961961

RESUMO

The study aimed to evaluate the impact of varying modulus of elasticity (MOE) values of dental implants on the deformation and von Mises stress distribution in implant systems and peri-implant bone tissues under dynamic cyclic loading. The implant-bone interface was characterised as frictional contact, and the initial stress was induced using the interference fit method to effectively develop a finite element model for an immediately loaded implant-supported denture. Using the Ansys Workbench 2021 R2 software, an analysis was conducted to examine the deformation and von Mises stress experienced by the implant-supported dentures, peri-implant bone tissue, and implants under dynamic loading across three simulated masticatory cycles. These findings were subsequently evaluated through a comparative analysis. The suprastructures showed varying degrees of maximum deformation across zirconia (Zr), titanium (Ti), low-MOE-Ti, and polyetheretherketone (PEEK) implant systems, registering values of 103.1 µm, 125.68 µm, 169.52 µm, and 844.06 µm, respectively. The Zr implant system demonstrated the lowest values for both maximum deformation and von Mises stress (14.96 µm, 86.71 MPa) in cortical bone. As the MOE increased, the maximum deformation in cancellous bone decreased. The PEEK implant system exhibited the highest maximum von Mises stress (59.12 MPa), whereas the Ti implant system exhibited the lowest stress (22.48 MPa). Elevating the MOE resulted in reductions in both maximum deformation and maximum von Mises stress experienced by the implant. Based on this research, adjusting the MOE of the implant emerged as a viable approach to effectively modify the biomechanical characteristics of the implant system. The Zr implant system demonstrated the least maximum von Mises stress and deformation, presenting a more favourable quality for preserving the stability of the implant-bone interface under immediate loading.

2.
Biomater Adv ; 163: 213939, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38954876

RESUMO

The bone turnover capability influences the acquisition and maintenance of osseointegration. The architectures of osteocyte three-dimensional (3D) networks determine the direction and activity of bone turnover through osteocyte intercellular crosstalk, which exchanges prostaglandins through gap junctions in response to mechanical loading. Titanium nanosurfaces with anisotropically patterned dense nanospikes promote the development of osteocyte lacunar-canalicular networks. We investigated the effects of titanium nanosurfaces on intercellular network development and regulatory capabilities of bone turnover in osteocytes under cyclic compressive loading. MLO-Y4 mouse osteocyte-like cell lines embedded in type I collagen 3D gels on titanium nanosurfaces promoted the formation of intercellular networks and gap junctions even under static culture conditions, in contrast to the poor intercellular connectivity in machined titanium surfaces. The osteocyte 3D network on the titanium nanosurfaces further enhanced gap junction formation after additional culturing under cyclic compressive loading simulating masticatory loading, beyond the degree observed on machined titanium surfaces. A prostaglandin synthesis inhibitor cancelled the dual effects of titanium nanosurfaces and cyclic compressive loading on the upregulation of gap junction-related genes in the osteocyte 3D culture. Supernatants from osteocyte monolayer culture on titanium nanosurfaces promoted osteocyte maturation and intercellular connections with gap junctions. With cyclic loading, titanium nanosurfaces induced expression of the regulatory factors of bone turnover in osteocyte 3D cultures, toward higher osteoblast activation than that observed on machined surfaces. Titanium nanosurfaces with anisotropically patterned dense nanospikes promoted intercellular 3D network development and regulatory function toward osteoblast activation in osteocytes activated by cyclic compressive loading, through intercellular crosstalk by prostaglandin.

3.
Mar Drugs ; 22(6)2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38921550

RESUMO

Although lipophilic shellfish toxins (LSTs) pose a significant threat to the health of seafood consumers, their systematic investigation and risk assessment remain scarce. The goals of this study were as follows: (1) analyze LST levels in commercially available shellfish in Zhejiang province, China, and determine factors influencing LST distribution; (2) assess the acute dietary risk of exposure to LSTs for local consumers during the red tide period; (3) explore potential health risks of LSTs in humans; and (4) study the acute risks of simultaneous dietary exposure to LSTs and paralytic shellfish toxins (PSTs). A total of 546 shellfish samples were collected. LSTs were detected in 89 samples (16.3%) at concentrations below the regulatory limits. Mussels were the main shellfish species contaminated with LSTs. Spatial variations were observed in the yessotoxin group. Acute exposure to LSTs based on multiple scenarios was low. The minimum tolerable exposure durations for LSTs calculated using the mean and the 95th percentile of consumption data were 19.7 and 4.9 years, respectively. Our findings showed that Zhejiang province residents are at a low risk of combined exposure to LSTs and PSTs; however, the risk may be higher for children under 6 years of age in the extreme scenario.


Assuntos
Exposição Dietética , Toxinas Marinhas , Frutos do Mar , China , Humanos , Frutos do Mar/análise , Toxinas Marinhas/análise , Toxinas Marinhas/toxicidade , Animais , Medição de Risco , Exposição Dietética/análise , Intoxicação por Frutos do Mar/prevenção & controle , Intoxicação por Frutos do Mar/etiologia , Contaminação de Alimentos/análise , Adulto , Criança , Pessoa de Meia-Idade , Alimentos Marinhos/análise , Pré-Escolar , Bivalves/química , Feminino , Adulto Jovem
4.
J Hazard Mater ; 474: 134800, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-38850955

RESUMO

Microplastics have emerged as a prominent global environmental contaminant, and they have been found in both human placenta and breast milk. However, the potential effects and mechanisms of maternal exposure to microplastics at various gestational stages on offspring neurodevelopment remain poorly understood. This investigation delves into the potential neurodevelopmental ramifications of maternal exposure to polystyrene nanoplastics (PS-NPs) during distinct phases of pregnancy and lactation. Targeted metabolomics shows that co-exposure during both pregnancy and lactation primarily engendered alterations in monoamine neurotransmitters within the cortex and amino acid neurotransmitters within the hippocampus. After prenatal exposure to PS-NPs, fetal rats showed appreciably diminished cortical thickness and heightened cortical cell proliferation. However, this exposure did not affect the neurodifferentiation of radial glial cells and intermediate progenitor cells. In addition, offspring are accompanied by disordered neocortical migration, typified by escalated superficial layer neurons proliferation and reduced deep layer neurons populations. Moreover, the hippocampal synapses showed significantly widened synaptic clefts and diminished postsynaptic density. Consequently, PS-NPs culminated in deficits in anxiolytic-like behaviors and spatial memory in adolescent offspring, aligning with concurrent neurotransmitter and synaptic alterations. In conclusion, this study elucidates the sensitive windows of early-life nanoplastic exposure and the consequential impact on offspring neurodevelopment.


Assuntos
Lactação , Exposição Materna , Efeitos Tardios da Exposição Pré-Natal , Animais , Feminino , Gravidez , Lactação/efeitos dos fármacos , Exposição Materna/efeitos adversos , Hipocampo/efeitos dos fármacos , Hipocampo/crescimento & desenvolvimento , Poliestirenos/toxicidade , Masculino , Microplásticos/toxicidade , Ratos Sprague-Dawley , Ratos , Neurônios/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Neurotransmissores/metabolismo , Nanopartículas/toxicidade , Encéfalo/efeitos dos fármacos , Encéfalo/crescimento & desenvolvimento
5.
Sci Data ; 11(1): 625, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38871800

RESUMO

Recent research in computational imaging largely focuses on developing machine learning (ML) techniques for image recognition in the medical field, which requires large-scale and high-quality training datasets consisting of raw images and annotated images. However, suitable experimental datasets for cervical spine X-ray are scarce. We fill the gap by providing an open-access Cervical Spine X-ray Atlas (CSXA), which includes 4963 raw PNG images and 4963 annotated images with JSON format (JavaScript Object Notation). Every image in the CSXA is enriched with gender, age, pixel equivalent, asymptomatic and symptomatic classifications, cervical curvature categorization and 118 quantitative parameters. Subsequently, an efficient algorithm has developed to transform 23 keypoints in images into 77 quantitative parameters for cervical spine disease diagnosis and treatment. The algorithm's development is intended to assist future researchers in repurposing annotated images for the advancement of machine learning techniques across various image recognition tasks. The CSXA and algorithm are open-access with the intention of aiding the research communities in experiment replication and advancing the field of medical imaging in cervical spine.


Assuntos
Algoritmos , Vértebras Cervicais , Aprendizado de Máquina , Humanos , Vértebras Cervicais/diagnóstico por imagem , Radiografia , Masculino , Feminino
6.
Jpn Dent Sci Rev ; 60: 163-174, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38828461

RESUMO

Peri-implant diseases, characterized by inflammatory conditions affecting peri-implant tissues, encompass peri-implant mucositis and peri-implantitis. Peri-implant mucositis is an inflammatory lesion limited to the mucosa around an implant, while peri-implantitis extends from the mucosa to the supporting bone, causing a loss of osseointegration. For non-surgical treatments, we tested the null hypothesis that the presence or absence of air-polishing made no difference. The study focused on randomized controlled trials (RCTs) comparing air-polishing with mechanical or ultrasonic debridement, evaluating outcomes such as bleeding on probing (BOP), probing depth (PD), plaque index/plaque score (PI/PS), clinical attachment level (CAL), bone loss, and mucosal recession (MR). Two independent reviewers conducted data extraction and quality assessments, considering short-term (<6 months) and long-term (≥6 months) follow-up periods. After screening, ten articles were included in the meta-analysis. In nonsurgical peri-implant disease management, air-polishing moderately mitigated short-term PI/PS for peri-implant mucositis and showed a similar improvement in long-term BOP and bone loss for peri-implantitis compared to the control group. The Egger test found no evidence of publication bias except for the long-term PI/PS of peri-implant mucositis. Leave-one-out analysis confirmed the stability of the results. The findings highlight the need for future research with longer-term follow-up and high-quality, multi-center, large-sample RCTs.

7.
Zhen Ci Yan Jiu ; 49(5): 526-533, 2024 May 25.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-38764125

RESUMO

Lumbar intervertebral disc herniation (LDH) is a common and frequently-occurring disease, which usually causes lumbar and leg pain. Studies have shown that acupuncture can improve the symptoms of LDH patients. In the present paper, we summarize the progress of researches on the mechanisms of acupuncture underlying improvement of symptoms of LDH in recent 10 years from 1) delaying the intervertibral disc degeneration (by down-regulating the expressions of matrix metalloproteinase ï¼»MMPï¼½-3 and MMP-4, up-regulating the expressions of diosaccharides and polyglycoprotein, inhibiting apoptosis and promoting mitochondrial autophagy of nucleus pulposus cells, etc.), 2) maintaining spinal column stability (by relieving rachiasmus and improving lumbar flexor and extensor muscle strength, lowering the degree of polyfidus edema and fat infiltration, and restoring the biomechanics of the spine), 3) regulating inflammation (by inhibiting the production of proinflammatory factors and increasing the production of anti-inflammatory factors, etc.), 4) regulating immune response (by promoting the activity of T cells and other immune cells, lowering serum levels of MMP-3, transforming growth factor-ß1 and prostaglandin E2, raising serum levels of IgA, IgG and IgM to improve immune function ), 5) modulating neural structure and function (by promoting myelin regeneration of sciatic nerve fibers, and reducing the edema of Schwann cells' cytoplasm and mitochondria, and improving neural ultrastructure, and sensory and motor functions of peripheral nerves, etc.), 6) relieving lumbar pain (by down-regulating expression of Ca2+/calmodulin-dependent protein kinase and activation of lumbar spinal cord glial cells, blocking nociceptive signal conduction, regulating the levels of pain-related factors, etc.), and 7) improving local microcirculation. These results may provide scientific evidence for acupuncture treatment of LDH.


Assuntos
Terapia por Acupuntura , Deslocamento do Disco Intervertebral , Humanos , Deslocamento do Disco Intervertebral/terapia , Animais , Vértebras Lombares
8.
Biosensors (Basel) ; 14(5)2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38785729

RESUMO

Glutamic acid decarboxylase antibody (GADAb) has emerged as a significant biomarker for clinical diagnosis and prognosis in type 1 diabetes (T1D). In this study, we investigated the potential utilization of glass capillary solid-state nanopores as a cost-effective and easily preparable platform for the detection of individual antigens, antibodies, and antigen-antibody complexes without necessitating any modifications to the nanopores. Our findings revealed notable characteristic variations in the translocation events of glutamic acid decarboxylase (GAD65) through nanopores under different voltage conditions, discovered that anomalous phenomenon of protein translocation events increasing with voltage may potentially be caused by the crowding of multiple proteins in the nanopores, and demonstrated that there are multiple components in the polyclonal antibodies (GADAb-poly). Furthermore, we achieved successful differentiation between GAD65, GADAb, and GADAb-GAD65 complexes. These results offer promising prospects for the development of a rapid and reliable GADAb detection method, which holds the potential to be applied in patient serum samples, thereby facilitating a label-free, cost-effective, and early diagnosis of type I diabetes.


Assuntos
Diabetes Mellitus Tipo 1 , Glutamato Descarboxilase , Nanoporos , Glutamato Descarboxilase/imunologia , Humanos , Diabetes Mellitus Tipo 1/diagnóstico , Técnicas Biossensoriais , Anticorpos , Vidro
9.
Ecotoxicol Environ Saf ; 278: 116393, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38714083

RESUMO

Micro(nano)plastic, as a new type of environmental pollutant, have become a potential threat to the life and health of various stages of biology. However, it is not yet clear whether they will affect brain development in the fetal stage. Therefore, this study aims to explore the potential effects of nanoplastics on the development of fetal rat brains. To assess the allocation of NPs (25 nm and 50 nm) in various regions of the fetal brain, pregnant rats were exposed to concentrations (50, 10, 2.5, and 0.5 mg/kg) of PS-NPs. Our results provided evidence of the transplacental transfer of PS-NPs to the fetal brain, with a prominent presence observed in several cerebral regions, notably the cerebellum, hippocampus, striatum, and prefrontal cortex. This distribution bias might be linked to the developmental sequence of each brain region. Additionally, we explored the influence of prenatal exposure on the myelin development of the cerebellum, given its the highest PS-NP accumulation in offspring. Compared with control rats, PS-NPs exposure caused a significant reduction in myelin basic protein (MBP) and myelin oligodendrocyte glycoprotein (MOG) expression, a decrease in myelin thickness, an increase in cell apoptosis, and a decline in the oligodendrocyte population. These effects gave rise to motor deficits. In conclusion, our results identified the specific distribution of NPs in the fetal brain following prenatal exposure and revealed that prenatal exposure to PS-NPs can suppress myelin formation in the cerebellum of the fetus.


Assuntos
Encéfalo , Bainha de Mielina , Poliestirenos , Animais , Feminino , Gravidez , Encéfalo/efeitos dos fármacos , Encéfalo/embriologia , Encéfalo/metabolismo , Bainha de Mielina/efeitos dos fármacos , Bainha de Mielina/metabolismo , Ratos , Poliestirenos/toxicidade , Poluentes Ambientais/toxicidade , Proteína Básica da Mielina/metabolismo , Exposição Materna , Nanopartículas/toxicidade , Apoptose/efeitos dos fármacos , Microplásticos/toxicidade , Ratos Sprague-Dawley , Troca Materno-Fetal , Feto/efeitos dos fármacos
10.
Purinergic Signal ; 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38802651

RESUMO

Obesity refers to the excessive accumulation of fat caused by a long-term imbalance between energy intake (EI) and energy expenditure (EE). Over recent years, obesity has become a major public health challenge. Caffeine is a natural product that has been demonstrated to exert anti-obesity effects; however, the mechanisms responsible for the effect of caffeine on weight loss have yet to be fully elucidated. Most obesity-related deaths are due to cardiovascular disease. Recent research has demonstrated that caffeine can reduce the risk of death from cardiovascular disease; thus, it can be hypothesized that caffeine may represent a new therapeutic agent for weight loss. In this review, we synthesize data arising from clinical and animal studies over the last decade and discuss the potential mechanisms by which caffeine may induce weight loss, focusing particularly on increasing energy consumption, suppressing appetite, altering lipid metabolism, and influencing the gut microbiota. Finally, we summarize the major challenges associated with caffeine and anti-obesity research and highlight possible directions for future research and development.

11.
J Bone Oncol ; 45: 100595, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38572352

RESUMO

Osteosclerosis in multiple myeloma (MM) is typically associated with rare POEMS syndrome, characterized by polyneuropathy (P), organomegaly (O), endocrinopathy (E), M-protein (M), and skin changes (S). However, osteosclerosis in multiple myeloma (MM) without POEMS syndrome, defined as non-POEMS Osteosclerotic MM, is exceedingly rare. We report a 70-year-old man with rib pain, remarkably high bone mineral density and diffuse osteosclerosis. The diagnosis of non-POEMS osteosclerotic MM was confirmed by biopsy and aspiration of bone marrow through surgery. A literature review spanning from 1990 identified 12 cases of similar non-POEMS osteosclerotic MM, including 5 males and 7 females with a mean age of 59.7 ± 10.6 years. The non-POEMS osteosclerotic MM can be divided into two subtypes, the osteosclerotic lesion subtype and the diffuse osteosclerosis subtype. Absence of polyneuropathy and organomegaly are the main factors that differentiate non-POEMS osteosclerotic MM from POEMS. A hyperactive osteoblastic process might be the etiology of diffuse osteosclerosis. Further research is needed to understand its etiology and pathophysiology.

12.
Zhongguo Zhong Yao Za Zhi ; 49(5): 1378-1387, 2024 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-38621986

RESUMO

This paper aims to study the pharmacokinetic differences of twelve effective constituents(succinic acid, neochlorogenic acid, chlorogenic acid, cryptochlorogenic acid, protocatechuic aldehyde, caffeic acid, 5-O-ferulogeninic acid, p-coumaric acid, nuciferine, quercetin, oleanolic acid, and ursolic acid) in Qihe Fenqing Yin in normal and diabetic rats. The diabetic rat model was established by a high-fat diet combined with intraperitoneal injection of streptozocin. A UHPLC-QTRAP-MS/MS method was established for the simultaneous determination of 12 constituents in the plasma of normal rats and model rats after a single intragastric administration of Qihe Fenqing Yin. The results show that the established analytical method has a good linear relationship with the 12 components, and the specificity, accuracy, precision, and stability meet the requirements. The computational pharmacokinetic parameters are fitted by DAS 3.2.8 software, and the results show that the half-life time(t_(1/2)) of the other nine components in the model group was longer than that in the normal group except for caffeic acid, 5-O-ferulogeninic acid, and oleanolic acid. The area under curve(AUC_(0-t)) of cryptochlorogenic acid, p-coumaric acid, ursolic acid, and oleanolic acid increases compared with the normal group. Meanwhile, mean residence time(MRT) delays. The "double peaks" of quercetin and nuciferine in the normal group are not observed in the model group, suggesting that the pharmacokinetic parameters of the drugs in the disease state are significantly different.


Assuntos
Ácidos Cafeicos , Ácidos Cumáricos , Diabetes Mellitus Experimental , Medicamentos de Ervas Chinesas , Ácido Oleanólico , Ratos , Animais , Ratos Sprague-Dawley , Quercetina , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas em Tandem/métodos , Medicamentos de Ervas Chinesas/farmacocinética
13.
Food Chem ; 449: 139259, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38626667

RESUMO

Diquat (DQ) is a typical bipyridine herbicide widely used to control weeds in fields and orchards. The severe toxicity of diquat poses a serious threat to the environment and human health. Metal-organic frameworks (MOFs) have received widespread attention due to their unique physical and chemical properties and applications in the detection of toxic and harmful substances. In this work, a two-dimensional (2D) Tb(III) functionalized MOF Tb(III)@1 (1 = [Cd(HTATB)(bimb)]n·H2O (Cd-MOF), H3TATB = 4,4',4″-triazine-2,4,6-tribenzoicacid, bimb = 1,4-bis((1H-imidazol-1-yl)methyl)benzene) has been prepared and characterized. Tb(III)@1 has excellent optical properties and high water and chemical stability. After the Tb(III) is fixed by the uncoordinated -COO- in the 1 framework, Tb(III)@1 emits the typical green fluorescence of the lanthanide ion Tb(III) through the "antenna effect". It is worth noting that Tb(III)@1 can be used as a dual emission fluorescence chemical sensor for the ratio fluorescence detection of pesticide DQ, exhibiting a relatively low detection limit of 0.06 nM and a wide detection range of 0-50 nM. After the addition of DQ, a rapid color change of Tb(III)@1 fluorescence from green to blue was observed due to the combined effects of IFE, FRET and dynamic quenching. Therefore, a simple test paper box has been designed for direct on-site determination of pesticide DQ. In addition, the developed sensor has been successfully applied to the detection of DQ in real samples (fruits a Yin-Xia Sun and Bo-Tao Ji contributed equally to this work and should be considered co-first authors.nd vegetables) with satisfactory results. The results indicate that the probe developed in this study has broad application prospects in both real sample detection and actual on-site testing.


Assuntos
Diquat , Contaminação de Alimentos , Malus , Estruturas Metalorgânicas , Solanum tuberosum , Térbio , Zea mays , Estruturas Metalorgânicas/química , Zea mays/química , Malus/química , Contaminação de Alimentos/análise , Diquat/química , Diquat/análise , Térbio/química , Solanum tuberosum/química , Herbicidas/análise , Herbicidas/química , Cádmio/análise , Limite de Detecção
14.
Alzheimers Dement ; 20(5): 3504-3524, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38605605

RESUMO

INTRODUCTION: Cognitive decline progresses with age, and Nr4a1 has been shown to participate in memory functions. However, the relationship between age-related Nr4a1 reduction and cognitive decline is undefined. METHODS: Nr4a1 expressions were evaluated by quantitative PCR and immunochemical approaches. The cognition of mice was examined by multiple behavioral tests. Patch-clamp experiments were conducted to investigate the synaptic function. RESULTS: NR4A1 in peripheral blood mononuclear cells decreased with age in humans. In the mouse brain, age-dependent Nr4a1 reduction occurred in the hippocampal CA1. Deleting Nr4a1 in CA1 pyramidal neurons (PyrNs) led to the impairment of cognition and excitatory synaptic function. Mechanistically, Nr4a1 enhanced TrkB expression via binding to its promoter. Blocking TrkB compromised the cognitive amelioration with Nr4a1-overexpression in CA1 PyrNs. DISCUSSION: Our results elucidate the mechanism of Nr4a1-dependent TrkB regulation in cognition and synaptic function, indicating that Nr4a1 is a target for the treatment of cognitive decline. HIGHLIGHTS: Nr4a1 is reduced in PBMCs and CA1 PyrNs with aging. Nr4a1 ablation in CA1 PyrNs impaired cognition and excitatory synaptic function. Nr4a1 overexpression in CA1 PyrNs ameliorated cognitive impairment of aged mice. Nr4a1 bound to TrkB promoter to enhance transcription. Blocking TrkB function compromised Nr4a1-induced cognitive improvement.


Assuntos
Envelhecimento , Disfunção Cognitiva , Membro 1 do Grupo A da Subfamília 4 de Receptores Nucleares , Animais , Disfunção Cognitiva/metabolismo , Membro 1 do Grupo A da Subfamília 4 de Receptores Nucleares/metabolismo , Membro 1 do Grupo A da Subfamília 4 de Receptores Nucleares/genética , Camundongos , Humanos , Envelhecimento/fisiologia , Masculino , Região CA1 Hipocampal/metabolismo , Células Piramidais/metabolismo , Receptor trkB/metabolismo , Leucócitos Mononucleares/metabolismo , Idoso , Feminino , Camundongos Endogâmicos C57BL
15.
Front Bioeng Biotechnol ; 12: 1337808, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38681963

RESUMO

Introduction: Magnetic Resonance Imaging (MRI) is essential in diagnosing cervical spondylosis, providing detailed visualization of osseous and soft tissue structures in the cervical spine. However, manual measurements hinder the assessment of cervical spine sagittal balance, leading to time-consuming and error-prone processes. This study presents the Pyramid DBSCAN Simple Linear Iterative Cluster (PDB-SLIC), an automated segmentation algorithm for vertebral bodies in T2-weighted MR images, aiming to streamline sagittal balance assessment for spinal surgeons. Method: PDB-SLIC combines the SLIC superpixel segmentation algorithm with DBSCAN clustering and underwent rigorous testing using an extensive dataset of T2-weighted mid-sagittal MR images from 4,258 patients across ten hospitals in China. The efficacy of PDB-SLIC was compared against other algorithms and networks in terms of superpixel segmentation quality and vertebral body segmentation accuracy. Validation included a comparative analysis of manual and automated measurements of cervical sagittal parameters and scrutiny of PDB-SLIC's measurement stability across diverse hospital settings and MR scanning machines. Result: PDB-SLIC outperforms other algorithms in vertebral body segmentation quality, with high accuracy, recall, and Jaccard index. Minimal error deviation was observed compared to manual measurements, with correlation coefficients exceeding 95%. PDB-SLIC demonstrated commendable performance in processing cervical spine T2-weighted MR images from various hospital settings, MRI machines, and patient demographics. Discussion: The PDB-SLIC algorithm emerges as an accurate, objective, and efficient tool for evaluating cervical spine sagittal balance, providing valuable assistance to spinal surgeons in preoperative assessment, surgical strategy formulation, and prognostic inference. Additionally, it facilitates comprehensive measurement of sagittal balance parameters across diverse patient cohorts, contributing to the establishment of normative standards for cervical spine MR imaging.

16.
J Esthet Restor Dent ; 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38605591

RESUMO

OBJECTIVES: The abutments produced with circular symmetry failed to accurately replicate the natural teeth's cervical shapes. The purpose of this study was to measure cervical cross-sections of maxillary anterior teeth using cone beam computed tomography (CBCT) images to design anatomic healing abutments. MATERIALS AND METHODS: CBCT data of 61 patients were analyzed using Ez3D Plus software. Measurements were taken at the cemento-enamel junction (CEJ) and 1 mm coronal to CEJ for maxillary central incisors, lateral incisors, and canines. Various parameters, including area, perimeter, and eight line segments in the distal (a), disto-palatal (b), palatal (c), mesio-palatal (d), mesial (e), mesio-labial (f), labial (g), and disto-labial (h) directions, were used to describe dental neck contours. The ratios (f/b and h/d) were analyzed, and differences based on sex and dental arch morphology were explored. RESULTS: Significant differences were found in area and perimeter between males and females, but not in f/b and h/d ratios. Differences in the f/b ratio were observed among dental arch morphologies for maxillary central incisors, lateral incisors, and canines. CONCLUSIONS: CBCT measurements of cervical cross-sections provide more accurate data for designing anatomic healing abutments. The fabrication of anatomical healing abutments needs to consider the influence of gender on cervical size and to explore the potential effect of arch shape on cervical morphology. CLINICAL SIGNIFICANCE: The novel method provides detailed measurements for the description of dental cervical contours for patients with bilateral homonymous teeth missing. The measurements of this study could be utilized to design more accurate anatomic healing abutments to create desired morphology of peri-implant soft tissue.

17.
Acta Biomater ; 180: 358-371, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38604464

RESUMO

Glaucoma valves (GVs) play an essential role in treating glaucoma. However, fibrosis after implantation has limited their long-term success in clinical applications. In this study, we aimed to develop a comprehensive surface-engineering strategy to improve the biocompatibility of GVs by constructing a microenvironment-regulated and dual-hydrophilic antifouling coating on a GV material (silicone rubber, SR). The coating was based on a superhydrophilic polydopamine (SPD) coating with good short-range superhydrophilicity and antifouling abilities. In addition, SPD coatings contain many phenolic hydroxyl groups that can effectively resist oxidative stress and the inflammatory microenvironment. Furthermore, based on its in situ photocatalytic free-radical polymerization properties, the SPD coating polymerized poly 2-methylacryloxyethylphosphocholine, providing an additional long-range hydrophilic and antifouling effect. The in vitro test results showed that the microenvironment-regulated and dual-hydrophilic coatings had anti-protein contamination, anti-oxidation, anti-inflammation, and anti-fiber proliferation capabilities. The in vivo test results indicated that this coating substantially reduced the fiber encapsulation formation of the SR material by inhibiting inflammation and fibrosis. This design strategy for dual hydrophilic coatings with microenvironmental regulation can provide a valuable reference for the surface engineering design of novel medical implantable devices. STATEMENT OF SIGNIFICANCE: Superhydrophilic polydopamine (SPD) coatings were prepared on silicone rubber (SR) by a two-electron oxidation method. Introduction of pMPC to SPD surface using photocatalytic radical polymerization to obtain a dual-hydrophilic coating. The dual-hydrophilic coating effectively modulates the oxidative and inflammatory microenvironment. This coating significantly reduced protein contamination and adhesion of inflammatory cells and fibroblasts in vitro. The coating-modified SR inhibits inflammatory and fibrosis responses in vivo, promising to serve the glaucoma valves.


Assuntos
Materiais Revestidos Biocompatíveis , Implantes para Drenagem de Glaucoma , Interações Hidrofóbicas e Hidrofílicas , Polímeros , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacologia , Animais , Polímeros/química , Polímeros/farmacologia , Indóis/química , Indóis/farmacologia , Propriedades de Superfície , Humanos , Glaucoma/patologia
19.
J Colloid Interface Sci ; 668: 50-58, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38669995

RESUMO

The ever-growing requirement for electrochemical energy storage has exacerbated the production of spent batteries, and the recycling of valuable battery components has recently received a remarkable attention. Among all battery components, copper foil is widely utilized as a current collector for stable zinc platting and stripping in zinc metal batteries (ZMBs) due to the perfect lattice matching of between metal copper and zinc, which is accompanied by the formation of multiple copper-zinc alloy components during the cycling process. Herein, a novel "two birds with one-stone" strategy through a one simple heat treatment step to revive the discarded copper foil in zinc metal battery is reported to further obtain a lithiophilic current collector (CuxZny-Cu) with multiple copper-zinc alloy components on the surface of the discarded copper foil. Such revived CuxZny-Cu current collector greatly reduces the lithium nucleation overpotential and realizes uniform lithium deposition and further inhibits lithium dendrites growth. The formed multiple CuxZny alloy phases on the surface of discarded copper foil exhibit a low Li nucleation overpotential of only 15 mV at 0.5 mA cm-2 for the first cycle. Moreover, such a CuxZny-Cu current collector could achieve stable cycle for 220 cycles at 0.5 mA cm-2 and 110 cycles at 1 mA cm-2 with a Li plating capacity of 1 mAh cm-2. Theoretical calculations indicate that, compared with pure Cu foil, the formed multiple alloy components of CuZn5, CuZn8, Cu0.61Zn0.39 and CuZn have low adsorption energy of -2.17, -2.55, -2.16 and -2.35 eV with lithium atoms, respectively, which result in reduced lithium nucleation overpotential. The full cell composed of CuxZny alloy current collector with deposition of 5 mAh cm-2 metal Li anode coupled with LiFePO4 (LFP) cathode exhibits a reversible capacity of 125.6 mAh/g after 110 cycles at a current of 0.5 C with capacity retention of 85.1 %. This work proposed a promising strategy to regenerate the discarded copper foil in rechargeable batteries.

20.
J Mech Behav Biomed Mater ; 155: 106543, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38636445

RESUMO

The potential of using specimens with a double-semicircular-notched configuration for performing tensile tests of orthodontic thermoplastic aligner materials was explored. Unnotched and double-semicircular-notched specimens were loaded in tension using a universal testing machine to determine their tensile strength, while finite element analysis (FEA) and digital image correlation (DIC) were used to estimate stress and strain, respectively. The shape did affect the tensile strength, demonstrating the importance of unifying the form of the specimen. During the elastic phase under tension, double-semicircular-notched specimens showed similar behavior to unnotched specimens. However, great variance was observed in the strain patterns of the unnotched specimens, which exhibited greater chance of end-failure, while the strain patterns of the double-semicircular-notched specimens showed uniformity. Considerable agreement between the theoretical (FEA) and practical models (DIC) further confirmed the validity of the double-semicircular-notched models.


Assuntos
Análise de Elementos Finitos , Teste de Materiais , Estresse Mecânico , Resistência à Tração , Teste de Materiais/instrumentação , Testes Mecânicos , Plásticos , Temperatura , Aparelhos Ortodônticos , Fenômenos Mecânicos
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