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1.
Cell ; 138(1): 114-28, 2009 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-19596239

RESUMEN

We describe a broad mechanistic framework for the transcriptional induction of mammalian primary response genes by Toll-like receptors and other stimuli. One major class of primary response genes is characterized by CpG-island promoters, which facilitate promiscuous induction from constitutively active chromatin without a requirement for SWI/SNF nucleosome remodeling complexes. The low nucleosome occupancy at promoters in this class can be attributed to the assembly of CpG islands into unstable nucleosomes, which may lead to SWI/SNF independence. Another major class consists of non-CpG-island promoters that assemble into stable nucleosomes, resulting in SWI/SNF dependence and a requirement for transcription factors that promote selective nucleosome remodeling. Some stimuli, including serum and tumor necrosis factor-alpha, exhibit a strong bias toward activation of SWI/SNF-independent CpG-island genes. In contrast, interferon-beta is strongly biased toward SWI/SNF-dependent non-CpG-island genes. By activating a diverse set of transcription factors, Toll-like receptors induce both classes and others for an optimal response to microbial pathogens.


Asunto(s)
Ensamble y Desensamble de Cromatina , Islas de CpG , Activación Transcripcional , Animales , Linfocitos T CD4-Positivos/metabolismo , Proteínas Cromosómicas no Histona/metabolismo , Humanos , Factor 3 Regulador del Interferón/metabolismo , Lipopolisacáridos/inmunología , Ratones , Nucleosomas/metabolismo , Regiones Promotoras Genéticas , Factores de Transcripción/metabolismo , Transcripción Genética
2.
Genet Epidemiol ; 46(7): 395-414, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35583099

RESUMEN

Risk evaluation to identify individuals who are at greater risk of cancer as a result of heritable pathogenic variants is a valuable component of individualized clinical management. Using principles of Mendelian genetics, Bayesian probability theory, and variant-specific knowledge, Mendelian models derive the probability of carrying a pathogenic variant and developing cancer in the future, based on family history. Existing Mendelian models are widely employed, but are generally limited to specific genes and syndromes. However, the upsurge of multigene panel germline testing has spurred the discovery of many new gene-cancer associations that are not presently accounted for in these models. We have developed PanelPRO, a flexible, efficient Mendelian risk prediction framework that can incorporate an arbitrary number of genes and cancers, overcoming the computational challenges that arise because of the increased model complexity. We implement an 11-gene, 11-cancer model, the largest Mendelian model created thus far, based on this framework. Using simulations and a clinical cohort with germline panel testing data, we evaluate model performance, validate the reverse-compatibility of our approach with existing Mendelian models, and illustrate its usage. Our implementation is freely available for research use in the PanelPRO R package.


Asunto(s)
Predisposición Genética a la Enfermedad , Neoplasias , Teorema de Bayes , Estudios de Cohortes , Humanos , Modelos Genéticos , Neoplasias/genética
3.
Stem Cells ; 40(9): 818-830, 2022 09 26.
Artículo en Inglés | MEDLINE | ID: mdl-35728620

RESUMEN

Nerve growth factor (NGF) is the best-characterized neurotrophin and is primarily recognized for its key role in the embryonic development of the nervous system and neuronal cell survival/differentiation. Recently, unexpected actions of NGF in bone regeneration have emerged as NGF is able to enhance the osteogenic differentiation of mesenchymal stem cells. However, little is known regarding how NGF signaling regulates osteogenic differentiation through epigenetic mechanisms. In this study, using human dental mesenchymal stem cells (DMSCs), we demonstrated that NGF mediates osteogenic differentiation through p75NTR, a low-affinity NGF receptor. P75NTR-mediated NGF signaling activates the JNK cascade and the expression of KDM4B, an activating histone demethylase, by removing repressive H3K9me3 epigenetic marks. Mechanistically, NGF-activated c-Jun binds to the KDM4B promoter region and directly upregulates KDM4B expression. Subsequently, KDM4B directly and epigenetically activates DLX5, a master osteogenic gene, by demethylating H3K9me3 marks. Furthermore, we revealed that KDM4B and c-Jun from the JNK signaling pathway work in concert to regulate NGF-mediated osteogenic differentiation through simultaneous recruitment to the promoter region of DLX5. We identified KDM4B as a key epigenetic regulator during the NGF-mediated osteogenesis both in vitro and in vivo using the calvarial defect regeneration mouse model. In conclusion, our study thoroughly elucidated the molecular and epigenetic mechanisms during NGF-mediated osteogenesis.


Asunto(s)
Células Madre Mesenquimatosas , Osteogénesis , Animales , Diferenciación Celular/genética , Epigénesis Genética , Histona Demetilasas/metabolismo , Humanos , Histona Demetilasas con Dominio de Jumonji/genética , Histona Demetilasas con Dominio de Jumonji/metabolismo , Células Madre Mesenquimatosas/metabolismo , Ratones , Factor de Crecimiento Nervioso/genética , Factor de Crecimiento Nervioso/metabolismo , Osteogénesis/genética , Receptor de Factor de Crecimiento Nervioso/genética , Receptor de Factor de Crecimiento Nervioso/metabolismo
4.
J Oncol Pharm Pract ; : 10781552231207854, 2023 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-37847779

RESUMEN

INTRODUCTION: Investigational drug service (IDS) oversees and manages use of investigational products. There is limited data on utility of pharmacy services in clinical trial conduct and outcomes, specifically on the value of a decentralized IDS pharmacist. METHODS: This is a quasi-experimental study conducted in an oncology clinical trial infusion unit. A retrospective chart review was done to reflect current practice from January through June 2022. A decentralized IDS pharmacist was piloted in December 2022. Data collected included number and types of consults, personnel requesting the consult, and intervention performed. A satisfaction questionnaire was conducted after the pilot program. RESULTS: A total of 16.3% (173 of 1062 patient visits) of pharmacy consults were completed in the centralized IDS pharmacy model, while 44.5% (81 of 182 patient visits) of pharmacy consults were completed during the decentralized IDS pharmacist pilot, p < .001. Decentralized IDS pharmacist completed 77% (62/81) of the consults during the pilot period. Most common types of consults were toxicity management (20%), electronic medical record issues (17%), and tubing and drug administration issues (16%). More than 80% of respondents to the satisfaction questionnaire responded that implementation of a decentralized IDS pharmacist is acceptable, appropriate, and feasible. CONCLUSION: This pilot study demonstrated that a decentralized IDS pharmacist in an oncology clinical trial infusion unit improved accessibility to an IDS pharmacist, increased pharmacy consults relevant to patient care and optimized centralized pharmacists medication distribution workflow. Further studies are needed to evaluate patient benefits from implementing decentralized IDS pharmacist in direct patient care activities.

5.
Clin Oral Investig ; 26(10): 6275-6281, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35695936

RESUMEN

OBJECTIVES: The purpose of this study was to investigate the heritability of dental cephalometric variables by analyzing vertical linear measurements and angular measurements of the upper incisor, canine, and first molar. MATERIALS AND METHODS: Among the 553 Korean patients who participated in twin studies conducted at Samsung Medical Center, 150 patients had their lateral cephalometric radiograph data included in this study. The group was comprised of 36 monozygotic (MZ) twins (males, 16 pairs; females, 20 pairs), 13 dizygotic (DZ) twins (males, 7 pairs; females, 6 pairs), and 26 same-sex sibling pairs (males, 11 pairs; females, 15 pairs). All patients were over 20 years old with a mean age of 39.75 years. Lateral cephalometric diagrams and linear measurements (6 vertical factors, 6 horizontal factors) were taken. Three axial planes were measured for each tooth; intraclass correlation coefficients (ICCs) were obtained for each group and heritability was calculated using Falconer's method. RESULTS: ICCs of vertical linear measurements (average 0.837, P < 0.01) and the tooth axis of the central incisor and canine (average 0.679, P < 0.001) were higher in the MZ group compared to the DZ and sibling groups; thus, these variables showed high heritability. CONCLUSIONS: Orthodontic treatment aiming to alter the tooth axis of the maxillary central incisor or canine or other vertical factors with greater heritability can be difficult, requiring strategic treatment planning to achieve desired treatment outcome and stability. CLINICAL RELEVANCE: The active early treatment to gain tooth eruption space can lead to normal tooth position.


Asunto(s)
Gemelos Dicigóticos , Gemelos Monocigóticos , Cefalometría , Femenino , Humanos , Masculino , Maxilar/diagnóstico por imagen , Hermanos , Gemelos Dicigóticos/genética , Gemelos Monocigóticos/genética
6.
Cancer ; 127(8): 1275-1285, 2021 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-33320347

RESUMEN

BACKGROUND: Little is known about the psychological outcomes of germline multigene panel testing, particularly among diverse patients and those with moderate-risk pathogenic variants (PVs). METHODS: Study participants (N = 1264) were counseled and tested with a 25- or 28-gene panel and completed a 3-month postresult survey including the Multidimensional Impact of Cancer Risk Assessment (MICRA). RESULTS: The mean age was 52 years, 80% were female, and 70% had cancer; 45% were non-Hispanic White, 37% were Hispanic, 10% were Asian, 3% were Black, and 5% had another race/ethnicity. Approximately 28% had a high school education or less, and 23% were non-English-speaking. The genetic test results were as follows: 7% had a high-risk PV, 6% had a moderate-risk PV, 35% had a variant of uncertain significance (VUS), and 52% were negative. Most participants (92%) had a total MICRA score ≤ 38, which corresponded to a mean response of "never," "rarely," or only "sometimes" reacting negatively to results. A multivariate analysis found that mean total MICRA scores were significantly higher (more uncertainty/distress) among high- and moderate-risk PV carriers (29.7 and 24.8, respectively) than those with a VUS or negative results (17.4 and 16.1, respectively). Having cancer or less education was associated with a significantly higher total MICRA score; race/ethnicity was not associated with the total MICRA score. High- and moderate-risk PV carriers did not differ significantly from one another in the total MICRA score, uncertainty, distress, or positive experiences. CONCLUSIONS: In a diverse population undergoing genetic counseling and multigene panel testing for hereditary cancer risk, the psychological response corresponded to test results and showed low distress and uncertainty. Further studies are needed to assess patient understanding and subsequent cancer screening among patients from diverse backgrounds. LAY SUMMARY: Multigene panel tests for hereditary cancer have become widespread despite concerns about adverse psychological reactions among carriers of moderate-risk pathogenic variants (mutations) and among carriers of variants of uncertain significance. This large study of an ethnically and economically diverse cohort of patients undergoing panel testing found that 92% "never," "rarely," or only "sometimes" reacted negatively to results. Somewhat higher uncertainty and distress were identified among carriers of high- and moderate-risk pathogenic variants, and lower levels were identified among those with a variant of uncertain significance or a negative result. Although the psychological response corresponded to risk, reactions to testing were favorable, regardless of results.


Asunto(s)
Asesoramiento Genético/psicología , Pruebas Genéticas/métodos , Células Germinativas , Neoplasias/genética , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Pueblo Asiatico/estadística & datos numéricos , Población Negra/estadística & datos numéricos , Estudios de Cohortes , Femenino , Tamización de Portadores Genéticos , Hispánicos o Latinos/estadística & datos numéricos , Humanos , Masculino , Persona de Mediana Edad , Neoplasias/etnología , Neoplasias/psicología , Distrés Psicológico , Medición de Riesgo/etnología , Factores Socioeconómicos , Incertidumbre , Población Blanca/estadística & datos numéricos , Adulto Joven
7.
Stat Med ; 40(3): 593-606, 2021 02 10.
Artículo en Inglés | MEDLINE | ID: mdl-33120437

RESUMEN

Commercialized multigene panel testing brings unprecedented opportunities to understand germline genetic contributions to hereditary cancers. Most genetic testing companies classify the pathogenicity of variants as pathogenic, benign, or variants of unknown significance (VUSs). The unknown pathogenicity of VUSs poses serious challenges to clinical decision-making. This study aims to assess the frequency of VUSs that are likely pathogenic in disease-susceptibility genes. Using estimates of probands' probability of having a pathogenic mutation (ie, the carrier score) based on a family history probabilistic risk prediction model, we assume the carrier score distribution for probands with VUSs is a mixture of the carrier score distribution for probands with positive results and the carrier score distribution for probands with negative results. Under this mixture model, we propose a likelihood-based approach to assess the frequency of pathogenicity among probands with VUSs, while accounting for the existence of possible pathogenic mutations on genes not tested. We conducted simulations to assess the performance of the approach and show that under various settings, the approach performs well with very little bias in the estimated proportion of VUSs that are likely pathogenic. We also estimate the positive predictive value across the entire range of carrier scores. We apply our approach to the USC-Stanford Hereditary Cancer Panel Testing cohort, and estimate the proportion of probands that have VUSs in BRCA1/2 that are likely pathogenic to be 10.12% [95%CI: 0%, 43.04%]. This approach will enable clinicians to target high-risk patients who have VUSs, allowing for early prevention interventions.


Asunto(s)
Neoplasias de la Mama , Predisposición Genética a la Enfermedad , Neoplasias de la Mama/genética , Femenino , Pruebas Genéticas , Humanos , Funciones de Verosimilitud , Mutación , Virulencia
8.
Proc Natl Acad Sci U S A ; 115(24): E5566-E5575, 2018 06 12.
Artículo en Inglés | MEDLINE | ID: mdl-29844188

RESUMEN

Although significant progress has been made in understanding epigenetic regulation of in vitro adipogenesis, the physiological functions of epigenetic regulators in metabolism and their roles in obesity remain largely elusive. Here, we report that KDM4B (lysine demethylase 4B) in adipose tissues plays a critical role in energy balance, oxidation, lipolysis, and thermogenesis. Loss of KDM4B in mice resulted in obesity associated with reduced energy expenditure and impaired adaptive thermogenesis. Obesity in KDM4B-deficient mice was accompanied by hyperlipidemia, insulin resistance, and pathological changes in the liver and pancreas. Adipocyte-specific deletion of Kdm4b revealed that the adipose tissues were the main sites for KDM4B antiobesity effects. KDM4B directly controlled the expression of multiple metabolic genes, including Ppargc1a and Ppara Collectively, our studies identify KDM4B as an essential epigenetic factor for the regulation of metabolic health and maintaining normal body weight in mice. KDM4B may provide a therapeutic target for treatment of obesity.


Asunto(s)
Histona Demetilasas con Dominio de Jumonji/metabolismo , Enfermedades Metabólicas/metabolismo , Obesidad/metabolismo , Adipocitos/metabolismo , Adipogénesis/fisiología , Tejido Adiposo/metabolismo , Animales , Peso Corporal/fisiología , Dieta Alta en Grasa/efectos adversos , Metabolismo Energético/fisiología , Epigénesis Genética/fisiología , Resistencia a la Insulina/fisiología , Lipólisis/fisiología , Ratones , Ratones Endogámicos C57BL , Oxidación-Reducción , Termogénesis/fisiología
9.
Proc Natl Acad Sci U S A ; 114(35): E7218-E7225, 2017 08 29.
Artículo en Inglés | MEDLINE | ID: mdl-28808036

RESUMEN

Patients with cleft lip and/or palate (CLP), who undergo numerous medical interventions from infancy, can suffer from lifelong debilitation caused by underdeveloped maxillae. Conventional treatment approaches use maxillary expansion techniques to develop normal speech, achieve functional occlusion for nutrition intake, and improve esthetics. However, as patients with CLP congenitally lack bone in the cleft site with diminished capacity for bone formation in the expanded palate, more than 80% of the patient population experiences significant postexpansion relapse. While such relapse has been a long-standing battle in craniofacial care of patients, currently there are no available strategies to address this pervasive problem. Estrogen, 17ß-estradiol (E2), is a powerful therapeutic agent that plays a critical role in bone homeostasis. However, E2's clinical application is less appreciated due to several limitations, including its pleiotropic effects and short half-life. Here, we developed a treatment strategy using an injectable system with photo-cross-linkable hydrogel (G) and nanodiamond (ND) technology to facilitate the targeted and sustained delivery of E2 to promote bone formation. In a preclinical expansion/relapse model, this functionalized E2/ND/G complex substantially reduced postexpansion relapse by nearly threefold through enhancements in sutural remodeling compared with unmodified E2 administration. The E2/ND/G group demonstrated greater bone volume by twofold and higher osteoblast number by threefold, compared with the control group. The E2/ND/G platform maximized the beneficial effects of E2 through its extended release with superior efficacy and safety at the local level. This broadly applicable E2 delivery platform shows promise as an adjuvant therapy in craniofacial care of patients.


Asunto(s)
Estrógenos/farmacología , Nanodiamantes/uso terapéutico , Técnica de Expansión Palatina/instrumentación , Animales , Labio Leporino/cirugía , Fisura del Paladar/terapia , Modelos Animales de Enfermedad , Femenino , Hidrogel de Polietilenoglicol-Dimetacrilato/farmacología , Nanoestructuras/uso terapéutico , Ratas , Ratas Sprague-Dawley , Recurrencia , Prevención Secundaria/métodos , Resultado del Tratamiento
10.
Am J Pathol ; 188(10): 2318-2327, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-30059656

RESUMEN

Medication-related osteonecrosis of the jaw (MRONJ) is a rare but detrimental intraoral lesion that predominantly occurs in patients with long-term use of antiresorptive agents, such as bisphosphonate and denosumab, a human anti-receptor activator of NF-κB ligand (RANKL) monoclonal antibody (Ab). Surgical intervention, such as tooth extraction, is a known risk factor for MRONJ, which is often performed to eliminate preexiting pathologic inflammatory conditions, such as periodontal diseases. Nonetheless, it remains unknown whether pre-existing periodontal disease condition exacerbates, or removal of such condition ameliorates, MRONJ development after tooth extraction. In this study, we combined the ligature-induced periodontitis and the tooth extraction mouse models under the administration of zoledronic acid (ZOL) or anti-RANKL Ab, and provide experimental evidence that a pre-existing pathologic inflammatory condition exacerbates MRONJ development after tooth extraction in mice. Under ZOL administration, tooth extraction alone induced ONJ lesions; however, extraction of a ligature-placed tooth further exacerbated ONJ development. When the ligature was removed and the inflammatory condition was deescalated, ONJ development was ameliorated. Anti-RANKL Ab administration resulted in similar outcomes. Interestingly, unlike ZOL-administered mice, anti-RANKL Ab-administered mice exhibited complete absence of osteoclasts, suggesting that physical presence of osteoclasts is not directly involved in ONJ development. Collectively, our study demonstrated that periodontal disease is a functionally linked risk factor that predisposes ONJ development after tooth extraction in the presence of bisphosphonate and denosumab.


Asunto(s)
Enfermedades Maxilomandibulares/prevención & control , Osteonecrosis/prevención & control , Periodontitis/terapia , Extracción Dental , Animales , Osteonecrosis de los Maxilares Asociada a Difosfonatos/prevención & control , Conservadores de la Densidad Ósea/toxicidad , Denosumab/toxicidad , Modelos Animales de Enfermedad , Femenino , Enfermedades Maxilomandibulares/inducido químicamente , Ligadura , Ratones Endogámicos C57BL , Osteonecrosis/inducido químicamente
11.
Am J Orthod Dentofacial Orthop ; 156(1): 113-124, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31256824

RESUMEN

Scissor bite often remains unnoticed by patients although it can adversely affect facial symmetry, jaw growth, and mastication. This case report illustrates the efficacy of temporary skeletal anchorage devices (TSADs) and a modified lingual arch in correcting severe scissor bite. A 28-year-old woman presented with severe scissor bite in the mandibular right posterior segment. To treat this condition, TSADs were used for maxillary posterior intrusion and a modified lingual arch for buccally uprighting mandibular posterior teeth. Long-term retention records demonstrate stable treatment results.


Asunto(s)
Oclusión Dental , Maloclusión Clase II de Angle/terapia , Maloclusión Clase I de Angle/terapia , Ortodoncia Correctiva/métodos , Adulto , Cefalometría/métodos , Femenino , Humanos , Maloclusión Clase I de Angle/diagnóstico por imagen , Maloclusión Clase I de Angle/cirugía , Maloclusión Clase II de Angle/diagnóstico por imagen , Maloclusión Clase II de Angle/cirugía , Mandíbula/diagnóstico por imagen , Mandíbula/patología , Mandíbula/cirugía , Maxilar/diagnóstico por imagen , Maxilar/patología , Maxilar/cirugía , Modelos Dentales , Métodos de Anclaje en Ortodoncia/instrumentación , Métodos de Anclaje en Ortodoncia/métodos , Diseño de Aparato Ortodóncico , Aparatos Ortodóncicos , Alambres para Ortodoncia , Ortodoncia Correctiva/instrumentación , Técnica de Expansión Palatina , Planificación de Atención al Paciente , Factores de Tiempo , Resultado del Tratamiento
12.
Stem Cells ; 34(3): 711-9, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26485430

RESUMEN

The high prevalence of cartilage diseases and limited treatment options create a significant biomedical burden. Due to the inability of cartilage to regenerate itself, introducing chondrocyte progenitor cells to the affected site is of significant interest in cartilage regenerative therapies. Tissue engineering approaches using human mesenchymal stem cells (MSCs) are promising due to their chondrogenic potential, but a comprehensive understanding of the mechanisms governing the fate of MSCs is required for precise therapeutic applications in cartilage regeneration. TGF-ß is known to induce chondrogenesis by activating SMAD signaling pathway and upregulating chondrogenic genes such as SOX9; however, the epigenetic regulation of TGF-ß-mediated chondrogenesis is not understood. In this report, we found that TGF-ß dramatically induced the expression of KDM4B in MSCs. When KDM4B was overexpressed, chondrogenic differentiation was significantly enhanced while KDM4B depletion by shRNA led to a significant reduction in chondrogenic potential. Mechanistically, upon TGF-ß stimulation, KDM4B was recruited to the SOX9 promoter, removed the silencing H3K9me3 marks, and activated the transcription of SOX9. Furthermore, KDM4B depletion reduced the occupancy of SMAD3 in the SOX9 promoter, suggesting that KDM4B is required for SMAD-dependent coactivation of SOX9. Our results demonstrate the critical role of KDM4B in the epigenetic regulation of TGF-ß-mediated chondrogenic differentiation of MSCs. Since histone demethylases are chemically modifiable, KDM4B may be a novel therapeutic target in cartilage regenerative therapy.


Asunto(s)
Diferenciación Celular/genética , Condrogénesis/genética , Histona Demetilasas con Dominio de Jumonji/biosíntesis , Células Madre Mesenquimatosas , Factor de Transcripción SOX9/biosíntesis , Factor de Crecimiento Transformador beta/genética , Cartílago/crecimiento & desarrollo , Cartílago/metabolismo , Línea Celular , Condrocitos/citología , Epigénesis Genética/genética , Regulación del Desarrollo de la Expresión Génica , Humanos , Histona Demetilasas con Dominio de Jumonji/genética , Osteogénesis/genética , Regiones Promotoras Genéticas , Regeneración , Factor de Transcripción SOX9/genética , Transducción de Señal/genética , Proteína smad3/genética
13.
Cleft Palate Craniofac J ; 54(6): 687-698, 2017 11.
Artículo en Inglés | MEDLINE | ID: mdl-28094562

RESUMEN

OBJECTIVE: Bone grafts in patients with cleft lip and palate can undergo a significant amount of resorption. The aim of this study was to investigate the effects of bisphosphonates (BPs) on the success of bone grafts in rats. DESIGN: Thirty-five female 15-week-old Fischer F344 Inbred rats were divided into the following experimental groups, each receiving bone grafts to repair an intraoral CSD: (1) Graft/saline: systemic administration of saline and (2) systemic administration of zoledronic acid immediately following surgery (graft/BP/T0), (3) 1 week postoperatively (graft/BP/T1), and (4) 3 weeks postoperatively (graft/BP/T2). As an additional control, the defect was left empty without bone graft. MAIN OUTCOME MEASURES: Microcomputed tomography and histologic analyses were performed in addition to evaluation of osteoclasts through tartrate-resistant acid phosphatase staining. RESULTS: Bone volume fraction (bone volume/tissue volume) for the delayed BP treatment groups (graft/BP/T1 = 45.4% ± 8.8%; graft/BP/T2 = 46.1% ± 12.4%) were significantly greater than that for the graft/saline group (31.0% ± 7.9%) and the graft/BP/T0 (27.6% ± 5.9%) 6 weeks postoperatively (P < .05). Hematoxylin and eosin staining confirmed an evident increase in bone volume and fusion of defect margins with existing palatal bone in the graft/BP/T1 and graft/BP/T2 groups. The graft/BP/T0 group showed the lowest bone volume with signs of acute inflammation. CONCLUSIONS: Delayed BP administration following cleft bone graft surgery led to significant increase in bone volume and integration compared with saline controls. However, BP injection immediately after the surgery did not enhance bone volume, and rather, may negatively affect bone graft incorporation.


Asunto(s)
Proceso Alveolar/efectos de los fármacos , Proceso Alveolar/cirugía , Difosfonatos/administración & dosificación , Difosfonatos/farmacología , Imidazoles/administración & dosificación , Imidazoles/farmacología , Proceso Alveolar/diagnóstico por imagen , Animales , Resorción Ósea , Trasplante Óseo/métodos , Femenino , Fémur/trasplante , Ilion/trasplante , Ratas , Ratas Endogámicas F344 , Microtomografía por Rayos X , Ácido Zoledrónico
14.
Am J Orthod Dentofacial Orthop ; 151(5): 887-897, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28457266

RESUMEN

INTRODUCTION: Bone-borne palatal expansion relies on mini-implant stability for successful orthopedic expansion. The large magnitude of applied force experienced by mini-implants during bone-borne expansion may lead to high failure rates. Use of bicortical mini-implant anchorage rather than monocortical anchorage may improve mini-implant stability. The aims of this study were to analyze and compare the effects of bicortical and monocortical anchorages on stress distribution and displacement during bone-borne palatal expansion using finite element analysis. METHODS: Two skull models were constructed to represent expansion before and after midpalatal suture opening. Three clinical situations with varying mini-implant insertion depths were studied in each skull model: monocortical, 1-mm bicortical, and 2.5-mm bicortical. Finite element analysis simulations were performed for each clinical situation in both skull models. Von Mises stress distribution and transverse displacement were evaluated for all models. RESULTS: Peri-implant stress was greater in the monocortical anchorage model compared with both bicortical anchorage models. In addition, transverse displacement was greater and more parallel in the coronal plane for both bicortical models compared with the monocortical model. Minimal differences were observed between the 1-mm and the 2.5-mm bicortical models for both peri-implant stress and transverse displacement. CONCLUSIONS: Bicortical mini-implant anchorage results in improved mini-implant stability, decreased mini-implant deformation and fracture, more parallel expansion in the coronal plane, and increased expansion during bone-borne palatal expansion. However, the depth of bicortical mini-implant anchorage was not significant.


Asunto(s)
Métodos de Anclaje en Ortodoncia/métodos , Técnica de Expansión Palatina , Tomografía Computarizada de Haz Cónico , Análisis de Elementos Finitos , Humanos , Maxilar/anatomía & histología , Maxilar/diagnóstico por imagen , Modelos Anatómicos , Hueso Paladar/anatomía & histología , Hueso Paladar/diagnóstico por imagen , Cráneo/anatomía & histología , Cráneo/diagnóstico por imagen
15.
Am J Orthod Dentofacial Orthop ; 150(2): 313-23, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27476365

RESUMEN

INTRODUCTION: The aims of this study were to evaluate the effects of rapid palatal expansion on the craniofacial skeleton of a patient with unilateral cleft lip and palate (UCLP) and to predict the points of force application for optimal expansion using a 3-dimensional finite element model. METHODS: A 3-dimensional finite element model of the craniofacial complex with UCLP was generated from spiral computed tomographic scans with imaging software (Mimics, version 13.1; Materialise, Leuven, Belgium). This model was imported into the finite element solver (version 12.0; ANSYS, Canonsburg, Pa) to evaluate transverse expansion forces from rapid palatal expansion. Finite element analysis was performed with transverse expansion to achieve 5 mm of anterolateral expansion of the collapsed minor segment to simulate correction of the anterior crossbite in a patient with UCLP. RESULTS: High-stress concentrations were observed at the body of the sphenoid, medial to the orbit, and at the inferior area of the zygomatic process of the maxilla. The craniofacial stress distribution was asymmetric, with higher stress levels on the cleft side. When forces were applied more anteriorly on the collapsed minor segment and more posteriorly on the major segment, there was greater expansion of the anterior region of the minor segment with minimal expansion of the major segment. CONCLUSIONS: The transverse expansion forces from rapid palatal expansion are distributed to the 3 maxillary buttresses. Finite element analysis is an appropriate tool to study and predict the points of force application for better controlled expansion in patients with UCLP.


Asunto(s)
Fisura del Paladar/terapia , Técnica de Expansión Palatina , Síndrome de Bandas Amnióticas/complicaciones , Fenómenos Biomecánicos , Niño , Fisura del Paladar/fisiopatología , Femenino , Análisis de Elementos Finitos , Humanos , Imagenología Tridimensional , Tomografía Computarizada Espiral
16.
Am J Orthod Dentofacial Orthop ; 150(6): 958-967, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27894545

RESUMEN

INTRODUCTION: Although current techniques for accelerated tooth movement often involve invasive surgical procedures, micro-osteoperforations (MOPs) using mini-implants may facilitate orthodontic tooth movement without raising flaps, reduce surgical risks, and increase patient acceptance. In this study, we evaluated the effectiveness of mini-implant-facilitated MOPs in inducing accelerated tooth movement and investigated the potential risks for root resorption. METHODS: Five MOPs were placed on the left side around the maxillary first molars in 6 rats using an automated mini-implant driver, whereas the right side received no MOPs as the control. Closed-coiled springs were secured from incisors to first molars for orthodontic tooth movement. Tooth movement was measured, and samples underwent radiologic and histologic analyses. RESULTS: The MOP side exhibited a 1.86-fold increase in the rate of tooth movement with decreased bone density and bone volume around the first molars compared with the control side. Hematoxylin and eosin and tartrate-resistant acid phosphatase analyses showed increased numbers of osteoclasts as well as new bone formation. Three-dimensional volumetric analysis of all 5 roots of the maxillary first molars demonstrated no statistically significant difference in root volumes. CONCLUSIONS: Mini-implant-facilitated MOPs accelerated tooth movement without increased risk for root resorption and therefore may become a readily available and efficient treatment option to shorten orthodontic treatment time with improved patient acceptance.


Asunto(s)
Alambres para Ortodoncia , Técnicas de Movimiento Dental/métodos , Animales , Masculino , Mandíbula/diagnóstico por imagen , Mandíbula/cirugía , Diente Molar/diagnóstico por imagen , Diente Molar/cirugía , Ratas , Ratas Sprague-Dawley , Resorción Radicular/diagnóstico por imagen , Resorción Radicular/etiología , Técnicas de Movimiento Dental/instrumentación , Microtomografía por Rayos X
17.
J Clin Invest ; 134(4)2024 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-38357922

RESUMEN

Chronic and elevated levels of the antiviral cytokine IFN-α in the brain are neurotoxic. This is best observed in patients with genetic cerebral interferonopathies such as Aicardi-Goutières syndrome. Cerebral interferonopathies typically manifest in early childhood and lead to debilitating disease and premature death. There is no cure for these diseases with existing treatments largely aimed at managing symptoms. Thus, an effective therapeutic strategy is urgently needed. Here, we investigated the effect of antisense oligonucleotides targeting the murine IFN-α receptor (Ifnar1 ASOs) in a transgenic mouse model of cerebral interferonopathy. Intracerebroventricular injection of Ifnar1 ASOs into transgenic mice with brain-targeted chronic IFN-α production resulted in a blunted cerebral interferon signature, reduced neuroinflammation, restoration of blood-brain barrier integrity, absence of tissue destruction, and lessened neuronal damage. Remarkably, Ifnar1 ASO treatment was also effective when given after the onset of neuropathological changes, as it reversed such disease-related features. We conclude that ASOs targeting the IFN-α receptor halt and reverse progression of IFN-α-mediated neuroinflammation and neurotoxicity, opening what we believe to be a new and promising approach for the treatment of patients with cerebral interferonopathies.


Asunto(s)
Interferón Tipo I , Enfermedades del Sistema Nervioso , Preescolar , Humanos , Ratones , Animales , Enfermedades Neuroinflamatorias , Oligonucleótidos Antisentido/genética , Oligonucleótidos Antisentido/farmacología , Interferón-alfa/genética , Ratones Transgénicos
18.
J Calif Dent Assoc ; 41(11): 813-7, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24341132

RESUMEN

A possible avenue to improve the clinical success of bone graft procedures in cleft lip and palate cases is to predetermine the bone donor site and the volume of graft material required for the recipient site. This study utilized cone beam computed tomography to generate three-dimensional reconstructions and volumetrically assess unilateral cleft lip and palate defects. Access to this information can assist in determining an optimal donor site for secondary alveolar bone grafting.


Asunto(s)
Injerto de Hueso Alveolar , Fisura del Paladar/diagnóstico por imagen , Tomografía Computarizada de Haz Cónico , Adolescente , Niño , Labio Leporino/patología , Labio Leporino/cirugía , Fisura del Paladar/cirugía , Estudios de Cohortes , Femenino , Humanos , Imagenología Tridimensional/métodos , Masculino , Técnica de Expansión Palatina , Cirugía Asistida por Computador
19.
Acta Neuropathol Commun ; 11(1): 166, 2023 10 19.
Artículo en Inglés | MEDLINE | ID: mdl-37853497

RESUMEN

Tau tubulin kinase-1 (TTBK1), a neuron-specific tau kinase, is highly expressed in the entorhinal cortex and hippocampal regions, where early tau pathology evolves in Alzheimer's disease (AD). The protein expression level of TTBK1 is elevated in the cortex brain tissues with AD patients compared to the control subjects. We therefore hypothesized that antisense oligonucleotide (ASO) based targeting Ttbk1 could prevent the accumulation of phosphorylated tau, thereby delaying the development of tau pathology in AD. Here we show that in vivo administration of ASO targeting mouse Ttbk1 (ASO-Ttbk1) specifically suppressed the expression of Ttbk1 without affecting Ttbk2 expression in the temporal cortex of PS19 tau transgenic mice. Central administration of ASO-Ttbk1 in PS19 mice significantly reduced the expression level of representative phosphor-tau epitopes relevant to AD at 8 weeks post-dose, including pT231, pT181, and pS396 in the sarkosyl soluble and insoluble fractions isolated from hippocampal tissues as determined by ELISA and pS422 in soluble fractions as determined by western blotting. Immunofluorescence demonstrated that ASO-Ttbk1 significantly reduced pS422 phosphorylated tau intensity in mossy fibers region of the dentate gyrus in PS19 mice. RNA-sequence analysis of the temporal cortex tissue revealed significant enrichment of interferon-gamma and complement pathways and increased expression of antigen presenting molecules (Cd86, Cd74, and H2-Aa) in PS19 mice treated with ASO-Ttbk1, suggesting its potential effect on microglial phenotype although neurotoxic effect was absent. These data suggest that TTBK1 is an attractive therapeutic target to suppress TTBK1 without compromising TTBK2 expression and pathological tau phosphorylation in the early stages of AD.


Asunto(s)
Enfermedad de Alzheimer , Tauopatías , Ratones , Animales , Humanos , Oligonucleótidos Antisentido/farmacología , Proteínas tau/genética , Proteínas tau/metabolismo , Fosforilación , Tauopatías/metabolismo , Enfermedad de Alzheimer/patología , Ratones Transgénicos , Hipocampo/patología , Corteza Entorrinal/metabolismo
20.
Sleep ; 46(8)2023 08 14.
Artículo en Inglés | MEDLINE | ID: mdl-37014012

RESUMEN

Craniofacial modification by orthodontic techniques is increasingly incorporated into the multidisciplinary management of sleep-disordered breathing in children and adolescents. With increasing application of orthodontics to this clinical population it is important for healthcare providers, families, and patients to understand the wide range of available treatments. Orthodontists can guide craniofacial growth depending on age; therefore, it is important to work with other providers for a team-based approach to sleep-disordered breathing. From infancy to adulthood the dentition and craniofacial complex change with growth patterns that can be intercepted and targeted at critical time points. This article proposes a clinical guideline for application of multidisciplinary care with emphasis on dentofacial interventions that target variable growth patterns. We also highlight how these guidelines serve as a roadmap for the key questions that will influence future research directions. Ultimately the appropriate application of these orthodontic techniques will not only provide an important therapeutic option for children and adolescents with symptomatic sleep-disordered breathing but may help also mitigate or prevent its onset.


Asunto(s)
Nonoxinol , Síndromes de la Apnea del Sueño , Adolescente , Humanos , Niño , Síndromes de la Apnea del Sueño/terapia
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