RESUMEN

Accumulating researches have reported that miR-17-92 cluster expression has strong association with tumorigenesis. In this study, we investigated the effects of 2 genetic polymorphisms in the promoter region of the miR-17-92 cluster and the risk and prognosis of endometrial cancer in northern Chinese women. Two polymorphisms (rs9588884 and rs982873) in the promoter of miR-17-92 cluster were genotyped by polymerase chain reaction and ligase detection reaction (PCR-LDR) in398 EC patients and 420 controls. The levels of miR-17-92 mRNA were investigated in 65EC tissues by real-time quantitative polymerase chain reaction (RT-qPCR). The impact of genetic features on the risk and clinical outcomes of EC was analyzed. The prognostic value of hsa-miR-17 and hsa-miR-20a in EC patients was assessed using the Kaplan-Meier plotter database. The results showed that a significant decrease in risk of EC with rs9588884 (GG vs CC: OR = 0.49, 95% CI = 0.32-0.78, P = .002; G vs C: OR = 0.75, 95% CI = 0.62-0.91, P = .005, respectively). Similarly, association was found between rs982873 and a decreased risk of EC (CC vs TT: OR = 0.53, 95% CI = 0.34-0.82, P = .004; C vs T: OR = 0.77, 95% CI = 0.63-0.94, P = .010, respectively). Moreover, survival analysis showed that the CG or GG genotype of rs9588884 may significantly increase overall survival (OS) compared with the CC genotype in the 5-year follow-up (HR = 0.49, 95% CI = 0.29-0.82 and HR = 0.36, 95% CI = 0.16-0.83, respectively). RT-qPCR results showed that the expression level of miR-17-92 mRNA in EC tissues with the rs9588884 GG genotype was significantly lower than those with the GC + CC genotype (P = .030). However, there was no significant difference in the prognosis and expression level of miR-17-92mRNA in tissues of EC patients with different genotypes of rs982873 (P = .343). In addition, analysis using Kaplan-Meier plotter database showed that high hsa-miR-20a expression was significantly correlated with poor OS in EC patients (HR = 1.63, 95% CI = 1.02-2.61, P = .039). The genetic polymorphisms rs9588884 and rs982873 in the promoter of miR-17-92 cluster decreased EC risk. Both rs9588884 and the expression level of hsa-miR-20a mRNA may be associated with its clinical outcome in EC patients.

Asunto(s)

Neoplasias Endometriales , MicroARNs , Polimorfismo de Nucleótido Simple , Regiones Promotoras Genéticas , ARN Largo no Codificante , Humanos , Femenino , Neoplasias Endometriales/genética , Neoplasias Endometriales/mortalidad , MicroARNs/genética , Persona de Mediana Edad , Pronóstico , ARN Largo no Codificante/genética , Regiones Promotoras Genéticas/genética , Predisposición Genética a la Enfermedad , China/epidemiología , Pueblo Asiatico/genética , Genotipo , Estudios de Casos y Controles , Anciano , Estimación de Kaplan-Meier

RESUMEN

Functional and esthetic results require accurate implant placement. We aimed to develop a predictive method for assessing guide layout and error on implant accuracy. A mathematical model for position error analysis was constructed based on triangular mesh data. This model examines the relationship between the spatial shifts of multiple surfaces and the spatial shifts of specific points. It involves encasing these surfaces in a cuboid bounding box and expressing them in a local coordinate system. The influence of positioning surface error and layout of surgical guide were researched with a simulation test. The result shows that error in the implant site position is directly related to the error in the guide locating surface under the same layout. When the guide locating surface layout varies, as the length, width, and height of the minimum cuboid envelope increase, the maximum deviation in the implant site position decreases.

Asunto(s)

Cirugía Asistida por Computador , Humanos , Cirugía Asistida por Computador/métodos , Simulación por Computador , Prótesis e Implantes , Modelos Teóricos

RESUMEN

OPINION STATEMENT: In addressing Gestational Trophoblastic Neoplasia (GTN), it is imperative to acknowledge the evolving landscape of treatment options, especially in light of the challenges posed by traditional methods. While historically, surgical interventions, radiation therapy, and chemotherapeutic agents have been the mainstays, the emergence of resistance and high-risk scenarios necessitates a reevaluation of our therapeutic approaches. Our review highlights the promising advancements in immunotherapy and molecular targeted therapy as viable alternatives for GTN management. The introduction of immune checkpoint inhibitors and kinase inhibitors offers a paradigm shift, particularly for patients resistant to conventional chemotherapy regimens. These novel therapies not only exhibit efficacy but also demonstrate manageable toxicity profiles, particularly in high-risk cases. However, integrating these innovative treatments into established international guidelines presents a formidable task. As we move forward, it is imperative that future research not only prioritizes fertility preservation but also rigorously evaluates long-term toxicity implications. International collaboration becomes pivotal in addressing the nuances of this rare and complex disease. In conclusion, our review underscores the need for a nuanced approach to GTN treatment, one that prioritizes reduced toxicity and improved quality of life. By embracing the advancements in immunotherapy and molecular targeted therapy, we can pave the way for more effective and patient-centered care in the management of GTN.

Asunto(s)

Manejo de la Enfermedad , Enfermedad Trofoblástica Gestacional , Inmunoterapia , Terapia Molecular Dirigida , Humanos , Femenino , Enfermedad Trofoblástica Gestacional/terapia , Enfermedad Trofoblástica Gestacional/tratamiento farmacológico , Terapia Molecular Dirigida/métodos , Embarazo , Inmunoterapia/métodos , Terapia Combinada/métodos , Terapia Combinada/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Resultado del Tratamiento

RESUMEN

Ovarian cancer (OC) was the fifth leading cause of cancer death and the deadliest gynecological cancer in women. This was largely attributed to its late diagnosis, high therapeutic resistance, and a dearth of effective treatments. Clinical and preclinical studies have revealed that tumor-infiltrating CD8+T cells often lost their effector function, the dysfunctional state of CD8+T cells was known as exhaustion. Our objective was to identify genes associated with exhausted CD8+T cells (CD8TEXGs) and their prognostic significance in OC. We downloaded the RNA-seq and clinical data from the Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases. CD8TEXGs were initially identified from single-cell RNA-seq (scRNA-seq) datasets, then univariate Cox regression, the least absolute shrinkage and selection operator (LASSO), and multivariate Cox regression were utilized to calculate risk score and to develop the CD8TEXGs risk signature. Kaplan-Meier analysis, univariate Cox regression, multivariate Cox regression, time-dependent receiver operating characteristics (ROC), nomogram, and calibration were conducted to verify and evaluate the risk signature. Gene set enrichment analyses (GSEA) in the risk groups were used to figure out the closely correlated pathways with the risk group. The role of risk score has been further explored in the homologous recombination repair deficiency (HRD), BRAC1/2 gene mutations and tumor mutation burden (TMB). A risk signature with 4 CD8TEXGs in OC was finally built in the TCGA database and further validated in large GEO cohorts. The signature also demonstrated broad applicability across various types of cancer in the pan-cancer analysis. The high-risk score was significantly associated with a worse prognosis and the risk score was proven to be an independent prognostic biomarker. The 1-, 3-, and 5-years ROC values, nomogram, calibration, and comparison with the previously published models confirmed the excellent prediction power of this model. The low-risk group patients tended to exhibit a higher HRD score, BRCA1/2 gene mutation ratio and TMB. The low-risk group patients were more sensitive to Poly-ADP-ribose polymerase inhibitors (PARPi). Our findings of the prognostic value of CD8TEXGs in prognosis and drug response provided valuable insights into the molecular mechanisms and clinical management of OC.

Asunto(s)

Linfocitos T CD8-positivos , Neoplasias Ováricas , Humanos , Femenino , Neoplasias Ováricas/genética , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/metabolismo , Pronóstico , RNA-Seq/métodos , Biomarcadores de Tumor/genética , Análisis de la Célula Individual/métodos , Regulación Neoplásica de la Expresión Génica , Análisis de Expresión Génica de una Sola Célula

RESUMEN

Introduction and importance: With the widespread use of positron emission tomography and computed tomography (PET/CT), a significantly greater proportion of patients with advanced ovarian cancer (OC) are now diagnosed with superior renal-vein lymph node metastases involving retrocrural and mediastinal nodes. To the authors' knowledge, retrocrural lymphadenectomy has not yet been reported in patients with OC. The authors performed retrocrural lymph node resection in a patient with ovarian cancer. Case presentation: A 64-year-old woman with ovarian cancer who had not undergone surgery upon initial diagnosis was admitted to the authors' hospital because tumour markers increased during bevacizumab maintenance therapy. PET/CT imaging revealed adnexal masses and multiple metastases in pelvic, para-aortic, retrocrural, and mediastinal lymph nodes. Reduction surgery was performed, and retrocrural lymph nodes were excised. However, the patient's postoperative course was complicated by a chylothorax. Because of the failure of conservative treatment, interventional embolization was performed, but failed to obstruct lymphatic vessels. The patient underwent reoperation. A fistula was located where Hem-o-lock clips penetrated the pleura, clearly indicating the injury site, which was then sutured and embedded in the surrounding diaphragmatic tissue and filled with gel sponge. The patient recovered from chylous leakage postoperatively. She later underwent chemotherapy and targeted maintenance therapy. Clinical discussion: The authors may have injured the communicating branch of the thoracic duct posterior to the diaphragm during the first operation and did not ligate it. The accumulated chylous fluid finally penetrated through the weak point on the pleura and led to chylothorax 3 days later. If conservative treatment or interventional embolization are unsuccessful, surgical treatment should be selected in time. Conclusion: The location of the retrocrural lymph node at the anastomosis of the chylous cistern and the thoracic duct may pose a significant risk of chylous leakage as a complication of lymphadenectomy. Full exposure of the surgical field and thorough ligation of the lymphatic vessels may lead to successful superior renal-vein lymphadenectomy.

RESUMEN

BACKGROUND: As a new intelligent polymer material, shape memory polymer (SMP) was a potential orthodontic appliance material. OBJECTIVE: This study aimed to investigate the thermodynamic responses of SMP under different loads via finite element analysis (FEA). METHODS: FEA specimens with a specification of 0.1 × 0.1 × 1 mm were designed. One end of the specimen was fixed, and the other was subjected to displacement load. Different loading, cooling, and heating rates were separately exerted on the specimen in its shape recovery process and used to observe the responses of the SMP constitutive model. Furthermore, specimens with various tensile elongation and sectional areas were simulated and used to elucidate their effect on shape recovering force. RESULTS: The specimens obtained a similar stress of 0.5, 0.44, and 1.07 Mpa for different loading, cooling, and heating rates after a long time. The shape recovering force of specimen increased from 0.0102 to 0.0315 N when the elongation improved from 10% to 40% and to 0.0408 N when the sectional areas were expanded to 0.2 × 0.2 mm. CONCLUSION: The stiffness of SMP was small at a high temperature but large at a low temperature. The effects of the loading, cooling, and heating rates on SMP can be eliminated after a long time. Furthermore, it was possible to increase the recovering force by increasing the elongation or expanding the sectional area of the specimen. The force was quadratically dependent on the elongation ratio.

RESUMEN

OBJECTIVE: The objective of the study was to find the most effective retracting method for the six maxillary anterior teeth with double-slot lingual brackets using a lever arm and miniscrew system. METHODS: Six finite element models were constructed: (A) a ribbon-wise archwire with a lever arm; (B) a ribbon-wise archwire with a lever arm and a sectional edgewise archwire; (C) a ribbon-wise archwire and a sectional edgewise archwire with a lever arm; (D) an edgewise archwire with a lever arm; (E) an edgewise archwire with a lever arm and a sectional ribbon-wise archwire; and (F) an edgewise archwire and a sectional ribbon-wise archwire with a lever arm. Initial displacements of maxillary teeth driven by a 1.5 N retraction force to the lever arm were analysed. RESULTS: In models B, C, E and F, anterior torque loss and inter-canine distance increases were significantly lower than that of the models without auxiliary archwires. In models C and F, the main archwire was less likely deformed. In models A, B and C, the displacement of canines in sagittal and vertical directions were less than in models D, E and F. CONCLUSIONS: The combination of edgewise and ribbon-wise archwires in double-slot lingual brackets effectively preserves the anterior arch shape. An edgewise archwire with lever arms on the auxiliary sectional ribbon-wise archwire is recommended for better performance in anterior teeth retraction.

Asunto(s)

Soportes Ortodóncicos , Análisis de Elementos Finitos , Incisivo , Diseño de Aparato Ortodóncico , Alambres para Ortodoncia , Técnicas de Movimiento Dental/métodos

RESUMEN

Abnormal gene expression caused by epigenetic changes, including DNA methylation, is associated with the development and progression of endometriosis. Grainyhead-like 2 gene (GRHL2), a suppressor of epithelial-mesenchymal transition, has been suggested to be associated with the occurrence, progression and poor survival of a variety of cancers. Although endometriosis is a benign disease, it has the biological behaviour of migration and invasion as malignant tumor. This study aims to determine whether the abnormal expression of the GRHL2 caused by aberrant methylation of its promoter is associated with the pathogenesis of ovarian endometriosis. Our results demonstrated that GRHL2 promoter region was significantly hypermethylated in the ectopic endometrium of patients with ovarian endometriosis compared with the normal endometrium of control patients. In contrast, the levels of GRHL2 mRNA and protein were significantly lower in the ectopic endometrium than in the control endometrium. Correlation analysis showed the methylation levels of GRHL2 were significantly negatively correlated with the mRNA expression of GRHL2. Moreover, the in vitro results suggested that the knockdown of GRHL2 could significantly increase the invasion and migration ability of EECs and may promote ZEB1 and vimentin expression while decreasing the expression of E-cadherin in EECs. Taken together, these results suggest that the low expression of GRHL2 caused by hypermethylation of the GRHL2 promoter is associated with ovarian endometriosis. The knockdown of GRHL2 may be involved in the occurrence of endometriosis by increasing EEC migration and invasion. This study provides more evidence for the hypothesis that endometriosis may be an epigenetic regulatory disorder.

Asunto(s)

Endometriosis , Neoplasias Ováricas , Metilación de ADN , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Endometriosis/patología , Endometrio/metabolismo , Femenino , Humanos , Neoplasias Ováricas/patología , Regiones Promotoras Genéticas , ARN Mensajero/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo

RESUMEN

AIM: Cytotoxic T-lymphocyte antigen-4 (CTLA-4), an inhibitory molecule on T-cells, plays a key role in tumorigenesis and progression. In the present study, we investigated the effects of three polymorphisms in the CTLA-4 gene on the risk of epithelial ovarian cancer and the clinical outcomes of patients. METHODS: A case-control study was performed in 527 epithelial ovarian cancer patients and 532 controls. Genotypes of three polymorphisms were determined by polymerase chain reaction/ligase detection reaction. A survival analysis was performed in 346 patients who were followed up for more than 3 years and 208 patients who were followed up for more than 5 years. RESULTS: There were significant differences in the genotype and allele distribution frequencies of the rs5742909 C/T polymorphism in CTLA-4 between patients and controls (p = 0.009 and p = 0.04, respectively). Compared with the CC genotype, the CT + TT genotype may significantly decrease the risk of developing epithelial ovarian cancer (OR = 0.69, 95% CI = 0.52-0.91). However, no significant association between the rs231775 G/A and rs3087243 G/A polymorphisms and epithelial ovarian cancer risk was observed. The survival analysis showed that three polymorphisms may not be related to the clinical outcomes of patients. CONCLUSION: Our results suggested that the rs5742909 C/T polymorphism of CTLA-4 may decrease the genetic susceptibility to epithelial ovarian cancer among northern Chinese women.

Asunto(s)

Antígeno CTLA-4 , Carcinoma Epitelial de Ovario , Predisposición Genética a la Enfermedad , Neoplasias Ováricas , Antígeno CTLA-4/genética , Carcinoma Epitelial de Ovario/genética , Estudios de Casos y Controles , Femenino , Genotipo , Humanos , Neoplasias Ováricas/genética , Polimorfismo de Nucleótido Simple

RESUMEN

This study aimed to develop a constitutive model for human periodontal ligament (PDL) by combining the hyperelastic and viscosity models. We performed the finite element analysis (FEA) to simulate the experimental processes of the PDL in vitro and in vivo tests to verify the developed model. The FEA results indicated that the simulative curves were consistent with the experimental curves in the PDL in vitro tests. Moreover, for the in vivo measurements, the simulative result of 0.6258 N was similar to the experimental value of 0.65 N. The study results can help orthodontists better understand the biomechanical characteristics of PDL.

Asunto(s)

Modelos Biológicos , Ligamento Periodontal , Fenómenos Biomecánicos , Simulación por Computador , Análisis de Elementos Finitos , Humanos , Estrés Mecánico

RESUMEN

The goal of this study was to identify genes that were differentially methylated and differentially expressed and their related signaling pathways in ovarian endometriosis tissue. First, the DNA methylation and gene expression profiles in the endometrial tissue of patients with ovarian endometriosis were studied using Illumina 450K methylation microarray analysis and the GSE141549 gene expression dataset. Second, differentially methylated and differentially expressed genes, herein referred to as differentially methylated/expressed genes, were identified and protein-protein interaction networks and functional analysis of these genes were determined. Third, qPCR and immunohistochemistry of patient samples was used to confirm the differential expression of a subset of differentially methylated/expressed genes. Finally, the GSE7305 dataset was used confirm the expression profile of differentially methylated/expressed genes and to determine the potential usefulness of these genes for diagnosis of endometriosis. A total of 37 hypermethylated low-expression genes and 66 hypomethylated high-expression genes were identified in ovarian endometriosis patients. Protein-protein interaction and functional analysis highlighted 8 hypermethylated low-expression genes (KRT19, KRT8, ESR1, PRL, SFN, IL20RA, IL2RB, and PAX8) and 4 hypomethylated high-expression genes (CYP11A1, NR5A1, ME1, and GSTM1). Significantly, both of these gene sets had a diagnostic value for patients with ovarian endometriosis. Signaling pathways that were identified included JAK-STAT (involving IL20RA and IL2RB), prolactin (involving PRL and ESR1), Staphylococcus aureus infection (involving KRT19), viral protein interaction with cytokine and cytokine receptor (involving IL20RA and IL2RB), cytokine-cytokine receptor interaction (involving IL20RA and IL2RB), and drug metabolism-cytochrome P450 (involving GSTM1). The differentially methylated/expressed genes and enriched signaling pathways identified in this study are likely to be associated with the process of ovarian endometriosis.

Asunto(s)

Biología Computacional , Endometriosis , Citocinas/genética , Metilación de ADN , Endometriosis/genética , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Receptores de Citocinas/genética

RESUMEN

BACKGROUND: The aim of the study was to investigate the role of the genetic variation of glutathione S-transferase M1 (GSTM1) in the development of ovarian endometriosis and endometriosis-related primary infertility risk. METHODS: This case-control study included 564 women with ovarian endometriosis and 576 normal women in the control group in northern China. The polymorphism of GSTM1 was genotyped by polymerase chain reaction (PCR)/ligase detection reaction method. To assess the biological significance of polymorphisms, the level of GSTM1 mRNA expression in patients' endometrial tissues with different genotypes was detected by quantitative real-time PCR (qRT-PCR). RESULTS: Compared with the positive genotype, the null genotype of GSTM1 was associated with the risk of developing ovarian endometriosis (OR = 1.29, 95% CI = 1.02-1.62). Further analysis showed that patients with a null genotype also had a significantly higher risk of primary infertility than patients with positive genotypes (OR = 1.59, 95% CI = 1.01-2.49). In addition, we found that GSTM1 mRNA expression was present in the endometrial tissue of all patients, but the expression level of patients with a positive genotype was nearly 10 times higher than that of patients with a negative genotype. CONCLUSION: Our results suggest that the GSTM1 polymorphism is not only related to the genetic susceptibility to ovarian endometriosis but also a potential molecular marker of primary infertility in patients with ovarian endometriosis.

Asunto(s)

Endometriosis , Estudios de Casos y Controles , Endometriosis/genética , Femenino , Predisposición Genética a la Enfermedad , Genotipo , Glutatión Transferasa/genética , Humanos , Infertilidad Femenina , Polimorfismo Genético

RESUMEN

The first enantioselective total synthesis of cerorubenic acid-III is described in detail. Different strategies and attempts, based on a type II [5+2] cycloaddition reaction, leading to the bicyclo[4.4.1] ring system with a strained bridgehead double bond, are depicted. Furthermore, sodium naphthalenide was found to be efficient in the chemoselective reduction of 8-oxabicyclo[3.2.1]octene, with three transformations completed in one operation. An unusual SN1 transannular cyclization reaction was applied to construct the synthetically challenging vinylcyclopropane moiety. This strategy enabled the total synthesis of cerorubenic acid-III in 19 steps.

Asunto(s)

Reacción de Cicloadición , Ciclización , Estereoisomerismo

RESUMEN

In the study of oral orthodontics, the dental tissue models play an important role in finite element analysis results. Currently, the commonly used alveolar bone models mainly have two kinds: the uniform and the non-uniform models. The material of the uniform model was defined with the whole alveolar bone, and each mesh element has a uniform mechanical property. While the material of the elements in non-uniform model was differently determined by the Hounsfield unit (HU) value of computed tomography (CT) images where the element was located. To investigate the effects of different alveolar bone models on the biomechanical responses of periodontal ligament (PDL), a clinical patient was chosen as the research object, his mandibular canine, PDL and two kinds of alveolar bone models were constructed, and intrusive force of 1 N and moment of 2 Nmm were exerted on the canine along its root direction, respectively, which were used to analyze the hydrostatic stress and the maximal logarithmic principal strain of PDL under different loads. Research results indicated that the mechanical responses of PDL had been affected by alveolar bone models, no matter the canine translation or rotation. Compared to the uniform model, if the alveolar bone was defined as the non-uniform model, the maximal stress and strain of PDL were decreased by 13.13% and 35.57%, respectively, when the canine translation along its root direction; while the maximal stress and strain of PDL were decreased by 19.55% and 35.64%, respectively, when the canine rotation along its root direction. The uniform alveolar bone model will induce orthodontists to choose a smaller orthodontic force. The non-uniform alveolar bone model can better reflect the differences of bone characteristics in the real alveolar bone, and more conducive to obtain accurate analysis results.

Asunto(s)

Ligamento Periodontal , Técnicas de Movimiento Dental , Fenómenos Biomecánicos , Simulación por Computador , Análisis de Elementos Finitos , Humanos , Modelos Biológicos , Estrés Mecánico

RESUMEN

Malignant ovarian germ cell tumors (MOGCTs) are rare and heterogeneous ovary tumors. We aimed to identify potential germline mutations and somatic mutations in MOGCTs by whole-exome sequencing. The peripheral blood and tumor samples from these patients were used to identify germline mutations and somatic mutations, respectively. For those genes with copy number alterations (deletion and duplication region), functional annotation was performed. Immunohistochemistry was performed to evaluate the expression of mutated genes corresponding to CNA deletion region and duplication region. In peripheral blood, copy number loss and gain were mostly found in yolk sac tumors (YSTs). Moreover, POU5F1 was the most significant mutated gene with mutation frequency >10% in both CNA deletion and duplication region. In addition, strong cytoplasm staining of POU5F1 (corresponding to CNA deletion region and duplication region) was found in two YST and nuclear staining in two dysgerminomas tumor samples. Genes corresponding to CNA deletion region were significantly enriched in the signaling pathway of regulating pluripotency of stem cells. In addition, genes corresponding to CNA duplication region were significantly enriched in the signaling pathways of RIG-I (DExD/H-box helicase 58)-like receptor, Toll-like receptor and nuclear factor (NF)-kappa. Keratin 4 (KRT4), ribosomal protein L14 (RPL14), proprotein convertase subtilisin/kexin type 6 (PCSK6), poly(A)-binding protein cytoplasmic 3 (PABPC3), and sterile alpha and TIR motif containing 1 (SARM1) mutations were detected in both peripheral blood and tumor samples. Identification of potential germline mutations and somatic mutations in MOGCTs may provide a new field in understanding the genetic feature of the rare biological tumor type in the ovary.

Asunto(s)

Mutación , Neoplasias de Células Germinales y Embrionarias/genética , Neoplasias Ováricas/genética , Adulto , Variaciones en el Número de Copia de ADN , Femenino , Mutación de Línea Germinal , Humanos , Secuenciación del Exoma , Adulto Joven

RESUMEN

OBJECTIVES: The objective of this study was to investigate the optimal range of rotational moment for the mandibular lateral incisor, canine and first premolar to determine tooth movements during orthodontic treatment using hydrostatic stress and logarithmic strain on the periodontal ligament (PDL) as indicators by numerical simulations. MATERIAL AND METHODS: Teeth, PDL and alveolar bone numerical models were constructed as analytical objects based on computed tomography (CT) images. Teeth were assumed to be rigid bodies, and rotational moments ranging from 1.0 to 4.0 Nmm were exerted on the crowns. PDL was defined as a hyperelastic-viscoelastic material with a uniform thickness of 0.25 mm. The alveolar bone model was constructed using a non-uniform material with varied mechanical properties determined based on Hounsfield unit (HU) values calculated using CT images, and its bottom was fixed completely. The optimal range values of PDL compressive and tensile stress were set as 0.47-12.8 and 18.8-51.2 kPa, respectively, whereas that of PDL logarithmic strain was set as 0.15-0.3%. RESULTS: The rotational tendency of PDL was around the long axis of teeth when loaded. The optimal range values of rotational moment for the mandibular lateral incisor, canine and first premolar were 2.2-2.3, 3.0-3.1 and 2.8-2.9 Nmm, respectively, referring to the biomechanical responses of loaded PDL. Primarily, the optimal range of rotational moment was quadratically dependent on the area of PDL internal surface (i.e. area of PDL internal surface was used to indicate PDL size), as described by the fitting formula. CONCLUSIONS: Biomechanical responses of PDL can be used to estimate the optimal range of rotational moment for teeth. These rotational moments were not consistent for all teeth, as demonstrated by numerical simulations. CLINICAL RELEVANCE: The quantitative relationship between the area of PDL internal surface and the optimal orthodontic moment can help orthodontists to determine a more reasonable moment and further optimise clinical treatment.

Asunto(s)

Incisivo , Ligamento Periodontal , Diente Premolar , Fenómenos Biomecánicos , Simulación por Computador , Análisis de Elementos Finitos , Modelos Biológicos , Ligamento Periodontal/diagnóstico por imagen , Estrés Mecánico , Técnicas de Movimiento Dental

RESUMEN

BACKGROUND: Orthodontic force is often statically measured in general, and only the initial force derived from appliances can be assessed. OBJECTIVE: We aimed to investigate a technological method for measuring dynamic force using tooth movement simulation. METHODS: Tooth movement was simulated in a softened wax model. A canine tooth was selected for evaluation and divided into the crown and root. A force transducer was plugged in and fixed between the two parts for measuring force. Forces on this tooth were derived by ordinary nickel-titanium (Ni-Ti) wire, hyperelastic Ni-Ti wire, low-hysteresis (LH) Ti-Ni wire and self-made glass fibre-reinforced shape memory polyurethane (GFRSMPU) wire. These forces were measured after the tooth movement. RESULTS: The canine tooth moved to the desired location, and only a 0.2 mm deviation remained. The changing trends and magnitudes of forces produced by the wires were consistent with the data reported by other studies. The tooth had a higher moving velocity with ordinary Ni-Ti wires in comparison to the other wires. Force attenuation for the GFRSMPU wire was the lowest (40.17%) at the end of the test, indicating that it provided light but continuous force. CONCLUSIONS: Mimicked tooth movements and dynamic force measurements were successfully determined in tooth movement simulation. These findings could help with estimating treatment effects and optimising the treatment plan.

Asunto(s)

Alambres para Ortodoncia , Técnicas de Movimiento Dental , Diente Canino , Ensayo de Materiales , Titanio

RESUMEN

OBJECTIVE: To explore the effects of two functional genetic variants of poly(ADP-ribose) polymerase-1 (PARP-1) on the susceptibility to epithelial ovarian cancer (EOC), the platinum-based chemotherapeutic response, and the prognosis of northern Chinese patients. STUDY DESIGN: This case-control study included 710 EOC patients in the case group and 700 healthy women in the control group. Two polymorphisms (rs1136410 and rs8679) of PARP-1 were genotyped by polymerase chain reaction and ligase detection reaction. RESULTS: The genotype frequencies of rs1136410 and rs8679 were not significantly different between the case and control groups. However, the CC genotype of rs1136410 was significantly associated with a favorable response to platinum drugs. Compared with the TT genotype, the CC genotype of rs1136410 was related to a reduced risk of platinum resistance (adjusted OR: 0.40; 95% CI = 0.24-0.67; P = 0.001). In addition, multivariable analysis containing clinical variables showed that patients who carried the rs1136410 CC genotype had a significantly improved progression-free survival compared with patients who carried the TT genotype (HR = 0.67, 95% CI = 0.47-0.97, P = 0.031). CONCLUSION: The rs1136410 polymorphism may serve as a potential marker for predicting the response to platinum agents and prognosis of EOC patients treated with surgery and platinum-based chemotherapy.

Asunto(s)

Neoplasias Ováricas , Platino (Metal) , Poli(ADP-Ribosa) Polimerasa-1/genética , Carcinoma Epitelial de Ovario/tratamiento farmacológico , Carcinoma Epitelial de Ovario/genética , Estudios de Casos y Controles , Femenino , Genotipo , Humanos , Neoplasias Ováricas/tratamiento farmacológico , Neoplasias Ováricas/genética , Platino (Metal)/uso terapéutico , Polimorfismo de Nucleótido Simple , Pronóstico

RESUMEN

OBJECTIVE: Polymorphisms of T cell immunoglobulin and mucin domain-containing molecule 3 (TIM-3) were reported to be associated with cancer risk and patients' survival. This study aims to investigate the correlation of TIM-3 polymorphisms with susceptibility to epithelial ovarian cancer (EOC) and patients' outcomes. METHODS: A total of 700 EOC patients and 710 healthy controls from North China were included. The polymorphisms (rs10053538, rs10515746 and rs1036199) were genotyped using the polymerase chain reaction/ligase detection reaction (PCR-LDR) method. Survival data were available for 339 patients after cytoreductive surgery. The expression level of TIM-3 was detected by real-time quantitative PCR (RT-qPCR). The prognostic value of TIM3 in EOC patients was assessed using the Kaplan-Meier plotter database. RESULTS: The results showed that none of the TIM3 polymorphisms were associated with the risk of developing EOC. Patients with the rs10053538 CA + AA genotype had worse PFS and OS than those with the CC genotype (HR = 1.49, 95% CI = 1.05-2.09, P = 0.024 and HR = 1.57, 95%CI = 1.09-2.26, P = 0.017, respectively). The RT-qPCR results showed that the expression levels of TIM-3 mRNA in EOC tissues with the rs10053538CA + AA genotypes were significantly higher than those with the CC genotype (P = 0.006). Analysis using the Kaplan-Meier plotter database showed that high expression of TIM-3 mRNA was significantly associated with shorter PFS and OS in EOC patients (HR = 1.57, 95%CI = 1.29-1.91, P < 0.001 and HR = 1.31, 95% CI = 1.06-1.63, P = 0.013, respectively). CONCLUSIONS: TIM-3 polymorphisms were not associated with risk of developing EOC. Both rs10053538 and the expression level of TIM-3 mRNA may be associated with its clinical outcome in EOC patients.

Asunto(s)

Carcinoma Epitelial de Ovario/genética , Procedimientos Quirúrgicos de Citorreducción , Receptor 2 Celular del Virus de la Hepatitis A/genética , Recurrencia Local de Neoplasia/epidemiología , Neoplasias Ováricas/genética , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma Epitelial de Ovario/diagnóstico , Carcinoma Epitelial de Ovario/mortalidad , Carcinoma Epitelial de Ovario/cirugía , Estudios de Casos y Controles , China/epidemiología , Supervivencia sin Enfermedad , Femenino , Estudios de Seguimiento , Regulación Neoplásica de la Expresión Génica , Predisposición Genética a la Enfermedad , Humanos , Estimación de Kaplan-Meier , Persona de Mediana Edad , Recurrencia Local de Neoplasia/genética , Neoplasias Ováricas/diagnóstico , Neoplasias Ováricas/mortalidad , Neoplasias Ováricas/cirugía , Ovario/patología , Ovario/cirugía , Polimorfismo de Nucleótido Simple , Pronóstico , Supervivencia sin Progresión , Regulación hacia Arriba , Adulto Joven

RESUMEN

Orthodontic tooth movement is mainly regulated by the biomechanical responses of loaded periodontal ligament (PDL). We investigated the effective intervals of orthodontic force in pure maxillary canine intrusion and extrusion referring to PDL hydrostatic stress and logarithmic strain. Finite element analysis (FEA) models, including a maxillary canine, PDL and alveolar bone, were constructed based on computed tomography (CT) images of a patient. The material properties of alveolar bone were non-uniformly defined using HU values of CT images; PDL was assumed to be a hyperelastic-viscoelastic material. The compressive stress and tensile stress ranging from 0.47 to 12.8 kPa and 18.8 to 51.2 kPa, respectively, were identified as effective for tooth movement; a strain 0.24% was identified as the lower limit of effective strain. The stress/strain distributions within PDL were acquired in canine intrusion and extrusion using FEA; root apex was the main force-bearing area in intrusion-extrusion movements and was more prone to resorption. Owing to the distinction of PDL biomechanical responses to compression and tension, the effective interval of orthodontic force was substantially lower in canine intrusion (80-90 g) than in canine extrusion (230-260 g). A larger magnitude of force remained applicable in canine extrusion. This study revised and complemented orthodontic biomechanical behaviours of tooth movement with intrusive-extrusive force and could further help optimize orthodontic treatment.

Asunto(s)

Diente Canino/fisiología , Análisis de Elementos Finitos , Maxilar/fisiología , Proceso Alveolar/fisiología , Fenómenos Biomecánicos , Simulación por Computador , Humanos , Presión Hidrostática , Modelos Biológicos , Ligamento Periodontal/fisiología , Estrés Mecánico , Técnicas de Movimiento Dental