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BACKGROUND: The reliability and repeatability of stereophotogrammetry and CT in 3-dimensional anthropometric facial analysis were investigated in this study, which also explored the clinical application of supine CT. METHOD: In this study, 3D CT and 3dMD stereophotogrammetry were used on 20 healthy volunteers. The fitting distance between stereophotogrammetry and CT scans at landmark points was measured, along with facial feature measurements (Al-Al) face width (Go-Go, Zy-Zy, Ex-Ex), and hemi-face height (Sn-Gn). The intraclass correlation coefficient (ICC) was employed to assess interrater agreement and to verify the reliability of the measurement methods. Paired t -analysis was utilized for analyzing intramethod displacement. RESULTS: The alare, nasion, and pronasale points were found to be minimally influenced by different positions and are more recommended as landmark points for registration. CT demonstrated good interrater reliability on all indicators. In stereophotogrammetry, measurements for Go-Go and Zy-Zy displayed an interclass correlation coefficient (ICC) of less than 0.75. Significant differences between the 2 methods were observed for En-En, Ex-Ex, and Go-Go ( P < 0.05). Specifically, CT analysis for Go-Go showed a measurement 2.34 mm larger than that obtained with the 3dMD method. CONCLUSION: Both CT and stereophotogrammetry were found to be reliable methods for evaluating facial soft tissue. It is speculated that Go-Go measurement is primarily influenced by factors such as different positions, facial expressions, and gravity. These variables should be carefully considered during the evaluation of the mandibular angle region.
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Face , Imageamento Tridimensional , Fotogrametria , Tomografia Computadorizada por Raios X , Humanos , Fotogrametria/métodos , Feminino , Face/diagnóstico por imagem , Face/anatomia & histologia , Masculino , Adulto , Tomografia Computadorizada por Raios X/métodos , Reprodutibilidade dos Testes , Adulto Jovem , Cefalometria/métodos , Antropometria/métodos , Voluntários Saudáveis , Pontos de Referência AnatômicosRESUMO
INTRODUCTION: In recent years, 3-dimensional (3D) printing has been widely used in regenerative medicine research and other fields because of its ability to customize macroscopic morphology and precisely control microstructure. Polymer scaffolds are 1 of the commonly used 3D bioprinting materials for defect repair and have recently been a research focus. Our article explored the bone-formation accelerating effect of 3D-printed porous scaffold Poly(glycerol sebacate) [PGS] in the critical bone defect of an enhancing rabbit mandibular model. Also, we overview and summarize the classification of 3D bioprinting materials and prospects for their various application scenarios in craniofacial reconstruction surgery. MATERIALS AND METHODS: A PGS elastomer scaffold was prepared by polymerizing equimolar amounts of sebacic acid and glycerol using a biological 3D printer. Six male New Zealand white rabbits were prepared (3 for the control group and 3 for the PGS group), each weighing 3 kg. Osteotomy was performed at the anterior edge of the ascending ramus of the mandible with a bone saw to open the 8 mm defect. Defects of the control group were empty, and defects of the PGS group were put into 8 mm-wide PGS elastomer scaffolds. The rabbits were euthanized 6 weeks after the operation, and the postoperative mandibles were collected. Information (presence or absence of pus from infection, nonunion, degree of macroscopic bone healing) was recorded, and the skeletal tissue was fixed in a paraformaldehyde solution. RESULTS: The mandible on the enhanced side was significantly longer than that on the opposite side, and the contralateral incisor was hyperplasia. The mandibles of rabbits in each group healed well, and there was no obvious local infection and purulence. The gross specimen appearance showed that both ends of the defect were connected. When comparing the reconstructed mandibles of the two groups, it is apparent that the width and thickness of the new bone in the PGS group were significantly better than that in the control group. CONCLUSIONS: This article verifies the effect of 3D polypore PGS scaffolds in animal craniomaxillofacial bone defects and introduces various application scenarios of 3D printing materials in craniomaxillofacial reconstruction surgery. There are quite good application prospects for 3D bioprinting in animal experiments and even clinical treatment of craniofacial defects.
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Bioimpressão , Alicerces Teciduais , Masculino , Coelhos , Animais , Alicerces Teciduais/química , Osteogênese , Mandíbula , Elastômeros , Impressão Tridimensional , Engenharia TecidualRESUMO
Rapid developments in 3-dimensional(3D) printing technologies in craniofacial plastic surgery have provided a new treatment modality for patients. In this article, we intend to share our institution's experience using 3D printing in 3 modes-namely, 3-dimensional printing for manufacturing contour models, guides, and implants. Fifty-nine patients were enrolled in our study between September 2009 and September 2021. Among the 3D printing-assisted technologies, 41 cases were used for congenital malformations, 82 for trauma repair, and 112 for cosmetic surgery. Preoperative design and postoperative data were compared and analyzed based on imaging data. In craniofacial plastic surgery, all patients had excellent postoperative objective bone measurements close to the preoperative design and improved esthetic appearance. Our survey of postoperative satisfaction showed that patients were quite satisfied with the surgery, especially concerning congenital deformities. Rapid prototyping 3-dimensional printing technology provides a practical and anatomically accurate means to produce patient-specific and disease-specific translational tools. These models can be used for surgical planning, simulation, and clinical evaluation. Expanding this technology in craniofacial plastic surgery will provide adequate assistance to practitioners and patients.
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Implantes Dentários , Procedimentos de Cirurgia Plástica , Cirurgia Assistida por Computador , Cirurgia Plástica , Humanos , Impressão Tridimensional , Cirurgia Assistida por Computador/métodosRESUMO
BACKGROUND: Hemifacial microsomia (HFM) is one of the most common congenital craniofacial condition often accompanied by masseter muscle involvement. U-Net neural convolution network for masseter segmentation is expected to achieve an efficient evaluation of masseter muscle. METHODS: A database was established with 108 patients with HFM from June 2012 to June 2019 in our center. Demographic data, OMENS classification, and 1-mm layer thick 3-dimensional computed tomography were included. Two radiologists manually segmented masseter muscles in a consensus reading as the ground truth. A test set of 20 cases was duplicated into 2 groups: an experimental group with the intelligent algorithm and a control group with manual segmentation. The U-net follows the design of 3D RoI-Aware U-Net with overlapping window strategy and references to our previous study of masseter segmentation in a healthy population system. Sorensen dice-similarity coefficient (DSC) muscle volume, average surface distance, recall, and time were used to validate compared with the ground truth. RESULTS: The mean DSC value of 0.794±0.028 for the experiment group was compared with the manual segmentation (0.885±0.118) with α=0.05 and a noninferiority margin of 15%. In addition, higher DSC was reported in patients with milder mandible deformity ( r =0.824, P <0.05). Moreover, intelligent automatic segmentation takes only 6.4 seconds showing great efficiency. CONCLUSIONS: We first proposed a U-net neural convolutional network and achieved automatic segmentation of masseter muscles in patients with HFM. It is a great attempt at intelligent diagnosis and evaluation of craniofacial diseases.
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Síndrome de Goldenhar , Humanos , Músculo Masseter , Inteligência Artificial , Redes Neurais de Computação , Algoritmos , Processamento de Imagem Assistida por Computador/métodosRESUMO
This study aimed to investigate the feasibility and accuracy of osteotomy and distractor placement using a robotic navigation system in a model surgical experiment of mandibular distraction osteogenesis for hemifacial microsomia. Imaging data from 5 patients with Pruzansky-Kaban type II (IIa: 4; IIb: 1) mandibular deformities were used to print 3D models for simulated mandibular distraction osteogenesis. In the experimental group, a robot-assisted surgical navigation system was used to perform the surgery under robotic guidance following registration, according to the preoperative design. Conventional surgery was performed in the control group, in which the operation was based on intraoperative estimations of the preoperative design by experienced surgeons. The accuracies of the osteotomy and distractor placement were assessed based on distance and angular error. Osteotomy accuracy was higher in the experimental group than in the control group, and the distance error ( t =9.311, P <0.001) and angular error ( t =5.385, P =0.001) were significantly reduced. The accuracy of distractor placement was also significantly higher in the experimental group, while the distance error ( t =3.048, P =0.016) and angular error ( t =3.524, P =0.024) were significantly reduced. The present results highlight the feasibility of robot-assisted distraction osteogenesis combined with electromagnetic navigation for improved surgical precision in clinical settings.
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Síndrome de Goldenhar , Osteogênese por Distração , Robótica , Humanos , Síndrome de Goldenhar/cirurgia , Osteogênese por Distração/métodos , Estudos de Viabilidade , Sistemas de Navegação Cirúrgica , Imageamento Tridimensional/métodos , Mandíbula/cirurgia , Assimetria Facial/cirurgiaRESUMO
Since our team reported the application of robot-assisted surgery in facial contouring surgery in 2020, further clinical trials with large samples have been conducted. This paper will report the interim results of a single-center, large-sample randomized controlled trial of the first robot developed by our team for facial contouring surgery. Meanwhile, this research field will be systematically reviewed and prospected.
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Procedimentos Ortopédicos , Procedimentos Cirúrgicos Robóticos , Humanos , Procedimentos Cirúrgicos Robóticos/métodos , Face , Ossos FaciaisRESUMO
Pronounced nongrowing season warming and changes in soil freeze-thaw (F-T) cycles can dramatically alter net methane (CH4 ) exchange rates between soils and the atmosphere. However, the magnitudes and drivers of warming impacts on CH4 uptake in different stages of the F-T cycle are poorly understood in cold alpine ecosystems, which have been found to be a net sink of atmospheric CH4 . Here, we reported a year-round ecosystem daily CH4 uptake in an alpine meadow on the Qinghai-Tibetan Plateau after a 5-year warming experiment that included a control, a low-level warming treatment (+2.4â at 5 cm soil depth), and a high-level warming treatment (+4.5â at 5 cm soil depth). We found that warming shortened the F-T cycle under the low-level warming and soils did not freeze under the high-level warming. Although both warming treatments increased the mean CH4 uptake rate, only the high-level warming significantly increased annual CH4 uptake compared to the control. The warming-induced stimulation of CH4 uptake mainly occurred in the cold season, which was mostly during spring thaw under low-level warming and during the frozen winter under high-level warming due to a longer period with thawed soil. We also found that warming significantly stimulated daily CH4 uptake mainly by reducing near-surface soil water content in the warm season, whereas both soil water content and temperature controlled daily CH4 uptake in different ways during the autumn freeze, frozen winter, and spring thaw periods of the control. Our study revealed a strong warming effect on CH4 uptake during the entire F-T cycle in the alpine meadow, especially the unfrozen winter. Our results also suggested the important roles of soil pH, available phosphorus, and methanotroph abundance in regulating annual CH4 uptake in response to warming, which should be incorporated into biogeochemical models for accurately forecasting CH4 fluxes under future climate scenarios.
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Pradaria , Metano , Ecossistema , Estações do Ano , Solo/química , ÁguaRESUMO
Plant and microbial diversity are key to determine ecosystem functioning. Despite the well-known role of local-scale α diversity in affecting vegetation biomass, the effects of community heterogeneity (ß diversity) of plants and soil microbes on above- and belowground biomass (AGB and BGB) across contrasting environments still remain unclear. Here, we conducted a dryness-gradient transect survey over 3000 km across grasslands on the Tibetan Plateau. We found that plant ß diversity was more dominant than α diversity in maintaining higher levels of AGB, while soil fungal ß diversity was the key driver in enhancing BGB. However, these positive effects of plant and microbial ß diversity on AGB and BGB were strongly weakened by increasing climatic dryness, mainly because higher soil available phosphorus caused by increasing dryness reduced both plant and soil fungal ß diversities. Overall, these new findings highlight the critical role of above- and belowground ß diversity in sustaining grassland biomass, raising our awareness to the ecological risks of large-scale biotic homogenization under future climate change.
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Ecossistema , Plantas , Biomassa , Pradaria , Fósforo , Solo , Microbiologia do SoloRESUMO
The stimulator of interferon genes (STING), one of the critical factors of innate immunity, is indicated to be closely related to angiogenesis. This study examined STING's role in angiogenesis and the formation of type H vessels, a specific subtype of bone vessels that regulates bone healing. Different concentrations of 2',3'-cGAMP, and H-151 or C-176 were applied to activate or inhibit STING, respectively. Human umbilical vein endothelial cells were used to examine the effect of STING on angiogenesis in vitro; cell viability, cell migration, and quantitative real-time polymerase chain reactions were performed. Also, the metatarsal experiment was applied as ex vivo proof. Bone fracture or defect mice models were used to examine the effect of STING in vivo; the bone healing process was evaluated by radiography weekly and by µCT on the 14th day after surgery. The formation of type H vessels (CD31hi Emcnhi endothelial cells) and osteogenesis (OCN-positive cells) was assessed using the cryosection and paraffin section. STING activation inhibited angiogenesis both in vitro and ex vivo and slowed down the bone healing process in vivo. Histological analysis showed an increased callus formation, fewer type H vessels, and almost no callus mineralization in the STING activation group compared to the control group. By contrast, H-151 (a hsSTING inhibitor) promoted angiogenesis at a low dose. Moreover, inhibition of mmSTING by C-176 enhanced type H vessels' formation, implying osteogenesis promotion in bone healing (higher bone volume density and more OCN-positive cells). Our data suggested that STING inhibition accelerates the bone healing process while enhancing type H vessel formation.
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Consolidação da Fratura , Proteínas de Membrana/fisiologia , Neovascularização Fisiológica , Animais , Células Endoteliais da Veia Umbilical Humana , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BLRESUMO
PURPOSE: A limited number of clinical studies have focused on the changing trends of facial soft tissue after mandibular angle ostectomy. We conducted this study to investigate the changes in facial muscles and facial soft tissue appearance before and after mandibular angle ostectomy. MATERIAL AND METHODS: A single-center retrospective cohort study was conducted on female patients admitted to our hospital for mandibular angle ostectomy between 2019 and 2020. The primary predictor variable was time (preoperative vs 6 months postoperative). The primary outcome variables were surface area and total volume of the manually delineated region of interest (ROI) for the masseter and temporalis muscles. We utilized computed tomography data to reconstruct 3-dimensional models to delineate muscle ROI and then measure them computationally. Secondary outcome variables were indicators of mandible appearance in soft tissue including bilateral mandibular angle distance, mandibular ramus height, and mandibular angle value. Age, preoperative body mass index, and ostectomy volume were chosen as covariates for correlation analysis with outcome variables. Paired t tests and Pearson correlation analysis were conducted, and P values < .05 were considered statistically significant. RESULTS: A total of 29 female patients (mean age, 26 years; range, 18 to 37 years) who underwent mandibular angle ostectomy in our hospital were included. The surface area and total volume of the masseter muscle ROI were reduced by 2,541.2 ± 1,925.0 mm2 (12.8%; P < .05) and 16,242.4 ± 12,646.8 mm3 (18.4%; P < .05), respectively, 6 months after surgery. In contrast, the surface area and total volume of the temporalis muscle ROI increased by 6,081.6 ± 6,169.4 mm2 (12.0%; P < .05) and 19,273.3 ± 21,666.2 mm3 (10.7%; P < .05), respectively. The ostectomy volume showed a correlation coefficient of 0.59 with postoperative masseter ROI change (P < .05). CONCLUSION: We observed statistically significant levels of atrophy of the masseter muscle ROI and expansion of the temporalis muscle ROI 6 months after mandibular angle ostectomy, which may account for appearance changes after surgery. Besides, ostectomy volume positively correlates with postoperative masseter ROI changes. In summary, our study provided empirical evidence illustrating soft tissue alterations in patients who have undergone mandibular angle ostectomy.
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Mandíbula , Músculo Masseter , Adulto , Face/diagnóstico por imagem , Feminino , Humanos , Mandíbula/diagnóstico por imagem , Mandíbula/cirurgia , Músculo Masseter/diagnóstico por imagem , Estudos Retrospectivos , Tomografia Computadorizada por Raios XRESUMO
In response to the rapid growth of credit-investigation data, data redundancy among credit-investigation agencies, privacy leakages of credit-investigation data subjects, and data security risks have been reported. This study proposes a privacy-protection scheme for a credit-investigation system based on blockchain technology, which realizes the secure sharing of credit-investigation data among multiple entities such as credit-investigation users, credit-investigation agencies, and cloud service providers. This scheme is based on blockchain technology to solve the problem of islanding of credit-investigation data and is based on zero-knowledge-proof technology, which works by submitting a proof to the smart contract to achieve anonymous identity authentication, ensuring that the identity privacy of credit-investigation users is not disclosed; this scheme is also based on searchable-symmetric-encryption technology to realize the retrieval of the ciphertext of the credit-investigation data. A security analysis showed that this scheme guarantees the confidentiality, the availability, the tamper-proofability, and the ciphertext searchability of credit-investigation data, as well as the fairness and anonymity of identity authentication in the credit-investigation data query. An efficiency analysis showed that, compared with similar identity-authentication schemes, the proof key of this scheme is smaller, and the verification time is shorter. Compared with similar ciphertext-retrieval schemes, the time for this scheme to generate indexes and trapdoors and return search results is significantly shorter.
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Face , Envelhecimento da Pele , Humanos , Face/diagnóstico por imagem , Pele , Fotografação/métodosRESUMO
Inhaled zinc oxide nanoparticles (ZnO-NPs) induce lung inflammation associated with oxidative stress. The NLRP3 inflammasome plays a pivotal role in the development of lung inflammation. However, the underlying effects of the NLRP3 inflammasome on ZnO-NPs-induced inflammation remain obscure. In the present study, reactive oxygen species (ROS) generation, expression of NLRP3, caspase-1 p10, and cytokines release of interleukin (IL)-1ß and IL-18 were determined after A549 cells were exposed to ZnO-NPs. The ROS scavenger N-acetyl-L-cysteine (NAC), nuclear factor kappa B (NF-κB inhibitor BAY11-7082, and NLRP3 inhibitor glibenclamide (GEL) were used to explore the mechanism of NLRP3 inflammasome activation-induced by ZnO-NPs. ZnO-NPs stimulation induced ROS generation and NF-κB p65 phosphorylation. Similarly, the expression of NLRP3 and caspase-1 p10 and the release of IL-1ß and IL-18 were significantly increased after ZnO-NPs treatment, which indicated that the NLRP3 inflammasome was activated by ZnO-NPs. Meanwhile, NAC pretreatment inhibited ZnO-NPs-induced activation of NF-κB and NLRP3 inflammasome. The NF-κB inhibitor BAY11-7082 did not affect ROS production but significantly reduced the NLRP3 inflammasome activation induced by ZnO-NPs. Furthermore, the ability of ZnO-NPs to increase the production of IL-1ß and IL-18 was significantly inhibited by GEL. The ZnO-NPs induced the activation of the NLRP3 inflammasome in A549 cells, which might be via a ROS-NF-κB-NLRP3 signaling pathway.
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Inflamassomos , Nanopartículas Metálicas/toxicidade , NF-kappa B/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Óxido de Zinco/toxicidade , Células A549 , Humanos , Inflamassomos/efeitos dos fármacos , Inflamassomos/metabolismoRESUMO
OBJECTIVE: To explore the regulation mechanism of coal tar pitch smoke extracts( CTPE) on tumor necrosis factor receptor-associated factor 2( TRAF2) mRNA expression in co-cultured model of human monocytes( THP-1) and BEAS-2B cells. METHODS: The co-cultured THP-1 and BEAS-2B cells were simulated by 3 µg/m L CTPE. The cells at passage 9 were treated with tumor necrosis factor-α( TNF-α) neutralization antibody and c-Jun N-terminal kinase( JNK) inhibitors SP600125, and continued toculture at passage 15( neutralizing antibody group) and established the BEAS-2B cells of same generation as control group. The expression of TRAF2 mRNA was detected by realtime fluorescent quantitative polymerase chain reaction. RESULTS: The expression of TRAF2 mRNA and c-Jun mRNA in different groups of TNF-α neutralization antibody and JNK kinase inhibitors SP600125 groups were decreased compared with CC10, respectively the groups of 48h( 0. 19 ± 0. 02) and 36h( 0. 03 ± 0. 02) were lowest. The expression of TRAF2 mRNA in groups of TNF-α neutralization antibody and JNK kinase inhibitors SP600125 groups( respectively 1. 73 ± 0. 04 and 1. 88 ± 0. 05) were both significantly increased compared with control group( 1. 07 ± 0. 06), and lower than CC15( 2. 23 ±0. 09). CONCLUSION: THP-1 could up-regulate the expression of TRAF2 mRNA through TNF-α in the BEAS-2B cells stimulated by CTPE, and there maybe negative feedback effect between TRAF2 and AP-1.
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Alcatrão , Células Epiteliais/metabolismo , RNA Mensageiro/genética , Fator 2 Associado a Receptor de TNF/genética , Fator de Necrose Tumoral alfa/metabolismo , Linhagem Celular , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno , Monócitos , Fator 2 Associado a Receptor de TNF/metabolismoRESUMO
Introduction: Mandible distraction osteogenesis (MDO) is widely used to reconstruct the mandible in patients with mild Hemifacial microsomia (HFM). However, the masseter's response to mandible distraction remains unclear. Methods: In this study, we analyze the effect of the surgical intervention on masseter muscle by a retrospective analysis. The procedure consisted of a five-day latent period, a three-week distraction period, and a six-month consolidation period. CT data were manually segmented and measured with Mimics software before surgery, within 3 months, and more than 1 year postoperatively. Masseter volume, masseter length, masseter width, and mandible ramus height were measured and analyzed using paired t-test, Pearson, and Spearman correlation analysis. Results: We included 21 patients with HFM who underwent mandible distraction osteogenesis from 2015 to 2020. The masseter volume on the affected side increased immediately after surgery from (6,505.33 ± 3,671.95) mm3 to (10,194.60 ± 5638.79) mm3, but decreased to (8,148.38 ± 3,472.57) mm3 at the second follow-up correlated to mandible ramus height (r = 0.395, P = 0.038). A similar trend was observed in changes in masseter length. Symmetry and width of masseter muscle had no longitudinal statistical significance. Discussion: Masseter muscle involvement benefits from MDO in the short term. To achieve long-term efficacy, more attention should be paid to muscle reconstruction.
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Introduction: This study evaluated the efficacy and learning curve of a maxillofacial surgical robotic system (MSRS) guided by electromagnetic navigation for mandibular angle ostectomy (MAO), compared to traditional surgical methods. Methods: The study utilized a controlled experiment involving thirty rabbits, paired divided into experimental and control groups. The experimental group underwent MAO using the MSRS, while the control group was treated with conventional surgical techniques. The surgeons performing the procedures were inexperienced in robotic surgery and MAO to assess the learning curve and the impact of robotic assistance. Key parameters measured included the accuracy of ostectomy, setup time, and ostectomy efficiency, with data analyzed through a paired-t test to compare the performance between the two groups. Results: The study indicated a significant reduction in ostectomy time for the experimental group, with improved accuracy and efficiency in ostectomy. The study found that robotic assistance could decrease the risk of complications and enhance surgical outcomes. It also highlighted the presence of an initial learning curve when adopting new robotic technologies, which could be mitigated through adequate training and simulation practices. Discussion: Using MSRS for MAO could lead to faster early learning curves and increased ostectomy efficiency compared to traditional surgical methods. It demonstrated the potential benefits of integrating robotic systems into craniofacial surgery, suggesting a promising direction for future surgical practices.
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Climate warming, often accompanied by extreme drought events, could have profound effects on both plant community structure and ecosystem functioning. However, how warming interacts with extreme drought to affect community- and ecosystem-level stability remains a largely open question. Using data from a manipulative experiment with three warming treatments in an alpine meadow that experienced one extreme drought event, we investigated how warming modulates resistance and recovery of community structural and ecosystem functional stability in facing with extreme drought. We found warming decreased resistance and recovery of aboveground net primary productivity (ANPP) and structural resistance but increased resistance and recovery of belowground net primary productivity (BNPP), overall net primary productivity (NPP), and structural recovery. The findings highlight the importance of jointly considering above- and belowground processes when evaluating ecosystem stability under global warming and extreme climate events. The stability of dominant species, rather than species richness and species asynchrony, was identified as a key predictor of ecosystem functional resistance and recovery, except for BNPP recovery. In addition, structural resistance of common species contributed strongly to the resistance changes in BNPP and NPP. Importantly, community structural resistance and recovery dominated the resistance and recovery of BNPP and NPP, but not for ANPP, suggesting the different mechanisms underlie the maintenance of stability of above- versus belowground productivity. This study is among the first to explain that warming modulates ecosystem stability in the face of extreme drought and lay stress on the need to investigate ecological stability at the community level for a more mechanistic understanding of ecosystem stability in response to climate extremes.
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Ecossistema , Pradaria , Secas , Clima , Mudança ClimáticaRESUMO
This study aimed to probe into the anatomic course of inferior alveolar nerve canal (IANC) in hemifacial microsomia (HFM) on a large scale, morphological observations and further quantitative study were performed. Patients were classified by Pruzansky-Kaban classification. The anatomic course of IANC was analyzed morphologically with three-dimensional (3D) imaging software among 248 patients. Seven distances between fixed landmarks on both sides were measured for 236 patients. The differences between affected and unaffected sides were compared. Significant differences were found in the entrance (P < 0.001), route (P < 0.001), and exit (P < 0.05) of IANC in type IIb and III HFM. The higher the degree of mandibular deformity was, the higher the incidence of IANC variation was (P < 0.05). The distances in the horizontal aspect of IANC including from mandibular foramen to mental foramen (P < 0.05) and from mental foramen to gonion (P < 0.05) were significantly shorter on the affected side. Abnormalities of the anatomical course of IANC exist in patients with Pruzansky-Kaban type IIb and type III HFM. The reduction of IANC on the affected side in the horizontal distance is more obvious. Three-dimensional imaging assessment is recommended before surgery.
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Síndrome de Goldenhar , Humanos , Tomografia Computadorizada por Raios X/métodos , Mandíbula/diagnóstico por imagem , Imageamento Tridimensional/métodos , Nervo Mandibular/diagnóstico por imagemRESUMO
Whether coexisting microplastics (MPs) affect the ecological and health risks of cadmium (Cd) in soils is a cutting-edge scientific issue. In this study, four typical Chinese soils were prepared as artificially Cd-contaminated soils with/without aged polystyrene (PS). TCLP and in vitro PBET model were used to determine the leachability (ecological risk) and oral bioaccessibility (human health risk) of soil Cd. The mechanisms by which MPs influence soil Cd were discussed from direct and indirect perspectives. Results showed that there was no significant difference in the leachability of soil Cd with/without aged PS. Additionally, aged PS led to a significant decrease in the bioaccessibility of soil Cd in gastric phase, but not in small intestinal phase. The increase in surface roughness and the new characteristic peaks (e.g., Si-O-Si) of aged PS directly accounted for the change in Cd bioaccessibility. The change in organic matter content indirectly accounted for the exceptional increase in Cd bioaccessibility of black soil with aged PS in small intestinal phase. Furthermore, the changes in cation exchange capacity and Cd mobility factor caused by aged PS explained the change in Cd leachability. These results contribute to a deeper understanding about environmental and public health in complicated emerging scenarios.
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Cádmio , Poluentes do Solo , Humanos , Idoso , Cádmio/toxicidade , Cádmio/análise , Microplásticos/toxicidade , Plásticos , Poliestirenos/toxicidade , Solo , Poluentes do Solo/toxicidade , Poluentes do Solo/análise , Disponibilidade BiológicaRESUMO
BACKGROUND: Mandibular distraction osteogenesis (MDO) is a major part of the treatment for hemifacial microsomia patients. Due to the narrow surgical field of the intraoral approach, osteotomy accuracy is highly dependent on the surgeons' experience. Electromagnetic (EM) tracking systems can achieve satisfying accuracy to provide helpful real-time surgical navigation. Our research team developed an EM navigation system based on artificial intelligence, which has been justified in improving the accuracy of osteotomy in the MDO in animal experiments. This study aims to clarify the effect of the EM navigation system in improving the MDO accuracy for hemifacial microsomia patients. METHODS: This study is designed as a single-centered and randomized controlled trial. Altogether, 22 hemifacial microsomia patients are randomly assigned to the experiment and control groups. All patients receive three-dimensional CT scans and preoperative surgical plans. The EM navigation system will be set up for those in the experiment group, and the control group will undergo traditional surgery. The primary outcome is the surgical precision by comparing the osteotomy position of pre- and postoperative CT scan images through the Geomagic Control software. The secondary outcomes include mandibular symmetry (occlusal plane deviation angle, mandibular ramus height, and body length), pain scale, and complications. Other indications, such as the adverse events of the system and the satisfactory score from patients and their families, will be recorded. DISCUSSION: This small sample randomized controlled trial intends to explore the application of an EM navigation system in MDO for patients, which has been adopted in other surgeries such as orthognathic procedures. Because of the delicate structures of children and the narrow surgical view, accurate osteotomy and protection of nearby tissue from injury are essential for successful treatment. The EM navigation system based on artificial intelligence adopted in this trial is hypothesized to provide precise real-time navigation for surgeons and optimally improve patient outcomes, including function and aesthetic results. The results of this trial will extend the application of new navigation technology in pediatric plastic surgery. TRIAL REGISTRATION: Chinese Clinical Trial Registry ChiCTR2200061565. Registered on 29 June 2022.