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1.
Bone ; 186: 117167, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38876270

RESUMO

We evaluated the potential of sclerostin antibody (SclAb) therapy to enhance osseointegration of dental and orthopaedic implants in a mouse model (Brtl/+) mimicking moderate to severe Osteogenesis Imperfecta (OI). To address the challenges in achieving stable implant integration in compromised bone conditions, our aim was to determine the effectiveness of sclerostin antibody (SclAb) at improving bone-to-implant contact and implant fixation strength. Utilizing a combination of micro-computed tomography, mechanical push-in testing, immunohistochemistry, and Western blot analysis, we observed that SclAb treatment significantly enhances bone volume fraction (BV/TV) and bone-implant contact (BIC) in Brtl/+ mice, suggesting a normalization of bone structure toward WT levels. Despite variations in implant survival rates between the maxilla and tibia, SclAb treatment consistently improved implant stability and resistance to mechanical forces, highlighting its potential to overcome the inherent challenges of OI in dental and orthopaedic implant integration. These results suggest that SclAb could be a valuable therapeutic approach for enhancing implant success in compromised bone conditions.

2.
JBMR Plus ; 8(1): ziad004, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38690127

RESUMO

Craniofacial and dentoalveolar abnormalities are present in all types of osteogenesis imperfecta (OI). Mouse models of the disorder are critical to understand these abnormalities and underlying OI pathogenesis. Previous studies on severely affected OI mice report a broad spectrum of craniofacial phenotypes, exhibiting some similarities to the human disorder. The Brtl/+ and G610c/+ are moderately severe and mild-type IV OI, respectively. Little is known about the aging effects on the craniofacial bones of these models and their homology to human OI. This study aimed to analyze the Brtl/+ and G610c/+ craniofacial morphometries during aging to establish suitability for further OI craniofacial bone intervention studies. We performed morphological measurements on the micro-CT-scanned heads of 3-wk-old, 3-mo-old, and 6-mo-old female Brtl/+ and G610c/+ mice. We observed that Brtl/+ skulls are shorter in length than WT (P < .05), whereas G610c/+ skulls are similar in length to their WT counterparts. The Brtl/+ mice exhibit alveolar bone with a porotic-like appearance that is not observed in G610c/+. As they age, Brtl/+ mice show severe bone resorption in both the maxilla and mandible (P < .05). By contrast, G610c/+ mice experience mandibular resorption consistently across all ages, but maxillary resorption is only evident at 6 mo (P < .05). Western blot shows high osteoclastic activities in the Brtl/+ maxilla. Both models exhibit delayed pre-functional eruptions of the third molars (P < .05), which are similar to those observed in some bisphosphonate-treated OI subjects. Our study shows that the Brtl/+ and G610c/+ mice display clear features found in type IV OI patients; both show age-related changes in the craniofacial growth phenotype. Therefore, understanding the craniofacial features of these models and how they age will allow us to select the most accurate mouse model, mouse age, and bone structure for the specific craniofacial bone treatment of differing OI groups.

3.
Laryngoscope ; 134(2): 552-561, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37345652

RESUMO

OBJECTIVES: As a critical component of the epithelial barrier, tight junctions (TJs) are essential in nasal mucosa against pathogen invasion. However, the function of TJs has rarely been reported in nasal inverted papilloma (NIP). This study aims to investigate the potential factors of TJs' abnormality in NIP. METHODS: We assessed the expression of ZO-1, occludin, claudin-1, claudin-3, and claudin-7 in healthy controls and NIP by real-time quantitative polymerase chain reaction and immunofluorescent staining. The correlation between TJs expression and neutrophil count, TH 1/TH 2/TH 17 and regulatory T cell biomarkers, and the proportion of nasal epithelial cells was investigated. RESULTS: Upregulation of ZO-1, occludin, claudin-1, and claudin-7, along with downregulation of claudin-3, was found in NIP compared to control (all p < 0.05). An abnormal proportion with a lower number of ciliated cells (control vs. NIP: 37.60 vs. 8.67) and goblet cells (12.52 vs. 0.33) together with a higher number of basal cells (45.58 vs. 124.00) in NIP. Meanwhile, claudin-3 was positively correlated with ciliated and goblet cells (all p < 0.01). Additionally, neutrophils were excessively infiltrated in NIP, negatively correlated with ZO-1, but positively with claudin-3 (all p < 0.05). Furthermore, FOXP3, IL-10, TGF-ß1, IL-5, IL-13, and IL-22 levels were induced in NIP (all p < 0.01). Occludin level was negatively correlated with IL-10, IL-5, IL-13, and IL-22, whereas ZO-1 was positively with TGF-ß1 (all p < 0.05). CONCLUSION: Nasal epithelial barrier dysfunction with TJs anomalies is commonly associated with abnormal proliferation and differentiation of epithelial cells and imbalance of immune and inflammatory patterns in NIP. LEVEL OF EVIDENCE: NA Laryngoscope, 134:552-561, 2024.


Assuntos
Papiloma Invertido , Junções Íntimas , Humanos , Interleucina-10/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Ocludina/metabolismo , Interleucina-13/metabolismo , Claudina-1/metabolismo , Claudina-3/genética , Claudina-3/metabolismo , Interleucina-5/metabolismo , Células Epiteliais/metabolismo
4.
JCO Clin Cancer Inform ; 7: e2300136, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38055914

RESUMO

In August 2022, the Cancer Informatics for Cancer Centers brought together cancer informatics leaders for its biannual symposium, Precision Medicine Applications in Radiation Oncology, co-chaired by Quynh-Thu Le, MD (Stanford University), and Walter J. Curran, MD (GenesisCare). Over the course of 3 days, presenters discussed a range of topics relevant to radiation oncology and the cancer informatics community more broadly, including biomarker development, decision support algorithms, novel imaging tools, theranostics, and artificial intelligence (AI) for the radiotherapy workflow. Since the symposium, there has been an impressive shift in the promise and potential for integration of AI in clinical care, accelerated in large part by major advances in generative AI. AI is now poised more than ever to revolutionize cancer care. Radiation oncology is a field that uses and generates a large amount of digital data and is therefore likely to be one of the first fields to be transformed by AI. As experts in the collection, management, and analysis of these data, the informatics community will take a leading role in ensuring that radiation oncology is prepared to take full advantage of these technological advances. In this report, we provide highlights from the symposium, which took place in Santa Barbara, California, from August 29 to 31, 2022. We discuss lessons learned from the symposium for data acquisition, management, representation, and sharing, and put these themes into context to prepare radiation oncology for the successful and safe integration of AI and informatics technologies.


Assuntos
Neoplasias , Radioterapia (Especialidade) , Humanos , Inteligência Artificial , Informática , Neoplasias/diagnóstico , Neoplasias/radioterapia
5.
Nature ; 609(7926): 265-268, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36071186

RESUMO

Blazars are active galactic nuclei (AGN) with relativistic jets whose non-thermal radiation is extremely variable on various timescales1-3. This variability seems mostly random, although some quasi-periodic oscillations (QPOs), implying systematic processes, have been reported in blazars and other AGN. QPOs with timescales of days or hours are especially rare4 in AGN and their nature is highly debated, explained by emitting plasma moving helically inside the jet5, plasma instabilities6,7 or orbital motion in an accretion disc7,8. Here we report results of intense optical and γ-ray flux monitoring of BL Lacertae (BL Lac) during a dramatic outburst in 2020 (ref. 9). BL Lac, the prototype of a subclass of blazars10, is powered by a 1.7 × 108 MSun (ref. 11) black hole in an elliptical galaxy (distance = 313 megaparsecs (ref. 12)). Our observations show QPOs of optical flux and linear polarization, and γ-ray flux, with cycles as short as approximately 13 h during the highest state of the outburst. The QPO properties match the expectations of current-driven kink instabilities6 near a recollimation shock about 5 parsecs (pc) from the black hole in the wake of an apparent superluminal feature moving down the jet. Such a kink is apparent in a microwave Very Long Baseline Array (VLBA) image.

6.
Radiat Res ; 197(4): 434-445, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-35090025

RESUMO

With a widely attended virtual kickoff event on January 29, 2021, the National Cancer Institute (NCI) and the Department of Energy (DOE) launched a series of 4 interactive, interdisciplinary workshops-and a final concluding "World Café" on March 29, 2021-focused on advancing computational approaches for predictive oncology in the clinical and research domains of radiation oncology. These events reflect 3,870 human hours of virtual engagement with representation from 8 DOE national laboratories and the Frederick National Laboratory for Cancer Research (FNL), 4 research institutes, 5 cancer centers, 17 medical schools and teaching hospitals, 5 companies, 5 federal agencies, 3 research centers, and 27 universities. Here we summarize the workshops by first describing the background for the workshops. Participants identified twelve key questions-and collaborative parallel ideas-as the focus of work going forward to advance the field. These were then used to define short-term and longer-term "Blue Sky" goals. In addition, the group determined key success factors for predictive oncology in the context of radiation oncology, if not the future of all of medicine. These are: cross-discipline collaboration, targeted talent development, development of mechanistic mathematical and computational models and tools, and access to high-quality multiscale data that bridges mechanisms to phenotype. The workshop participants reported feeling energized and highly motivated to pursue next steps together to address the unmet needs in radiation oncology specifically and in cancer research generally and that NCI and DOE project goals align at the convergence of radiation therapy and advanced computing.


Assuntos
Radioterapia (Especialidade) , Academias e Institutos , Humanos , National Cancer Institute (U.S.) , Radioterapia (Especialidade)/educação , Estados Unidos
7.
Clin Biomech (Bristol, Avon) ; 63: 41-47, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30825811

RESUMO

BACKGROUND: Hip fractures in older adults often result from a fall in the lateral direction. While younger adults tend to recover balance from a lateral perturbation with a single lateral sidestep, older adults are prone to multistep responses which are associated with an increased fall risk. This study compared the stepping characteristics and stability of single and multistep responses to lateral perturbation in healthy older adults. METHODS: Eighty-four older adults received lateral waist-pull perturbations to either side. Spatio-temporal stepping characteristics and balance stability were quantified. FINDINGS: Fewer steps were taken to recover balance when the first step was a lateral sidestep. The stability margin of single lateral sidesteps was greater than medial sidesteps and cross-over steps to the back but not significantly different from single cross-over steps to the front at step termination. Single step responses were more stable than multistep responses at step termination and at step initiation for lateral sidesteps and cross-over steps to the front. The decreased stability of multistep responses was attributed to an increased center of mass velocity and a smaller distance between the center of mass and base-of-support at step termination. INTERPRETATION: Although lateral sidesteps result in fewer steps than cross-over steps to the front, the stability margin was not significantly different at step termination. These results suggest difficulty terminating center of mass motion and/or inefficient center of mass control differentiates single and multistep responses. Future studies should investigate perturbation training and/or hip abductor muscle conditioning as a means of improving compensatory stepping reactions.


Assuntos
Acidentes por Quedas/prevenção & controle , Quadril/fisiologia , Músculo Esquelético/fisiologia , Equilíbrio Postural , Caminhada , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Movimento , Modalidades de Fisioterapia
8.
Genome Biol ; 19(1): 221, 2018 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-30567591

RESUMO

Biomarkers of aging can be used to assess the health of individuals and to study aging and age-related diseases. We generate a large dataset of genome-wide RNA-seq profiles of human dermal fibroblasts from 133 people aged 1 to 94 years old to test whether signatures of aging are encoded within the transcriptome. We develop an ensemble machine learning method that predicts age to a median error of 4 years, outperforming previous methods used to predict age. The ensemble was further validated by testing it on ten progeria patients, and our method is the only one that predicts accelerated aging in these patients.


Assuntos
Envelhecimento/metabolismo , Fibroblastos/metabolismo , Perfilação da Expressão Gênica , Transcriptoma , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Genômica/métodos , Humanos , Aprendizado de Máquina , Pessoa de Meia-Idade , Progéria/metabolismo , Adulto Jovem
9.
Am J Pathol ; 188(11): 2464-2473, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30142335

RESUMO

Heterotopic ossification (HO) occurs secondary to trauma, causing pain and functional limitations. Identification of the cells that contribute to HO is critical to the development of therapies. Given that innate immune cells and mesenchymal stem cells are known contributors to HO, we sought to define the contribution of these populations to HO and to identify what, if any, contribution circulating populations have to HO. A shared circulation was obtained using a parabiosis model, established between an enhanced green fluorescent protein-positive/luciferase+ donor and a same-strain nonreporter recipient mouse. The nonreporter mouse received Achilles tendon transection and dorsal burn injury to induce HO formation. Bioluminescence imaging and immunostaining were performed to define the circulatory contribution of immune and mesenchymal cell populations. Histologic analysis showed circulating cells present throughout each stage of the developing HO anlagen. Circulating cells were present at the injury site during the inflammatory phase and proliferative period, with diminished contribution in mature HO. Immunostaining demonstrated that most early circulatory cells were from the innate immune system; only a small population of mesenchymal cells were present in the HO. We demonstrate the time course of the participation of circulatory cells in trauma-induced HO and identify populations of circulating cells present in different stages of HO. These findings further elucidate the relative contribution of local and systemic cell populations to HO.


Assuntos
Queimaduras/complicações , Modelos Animais de Doenças , Inflamação/patologia , Células-Tronco Mesenquimais/patologia , Ossificação Heterotópica/patologia , Animais , Feminino , Inflamação/sangue , Inflamação/etiologia , Camundongos , Camundongos Endogâmicos C57BL , Ossificação Heterotópica/sangue , Ossificação Heterotópica/etiologia , Osteogênese , Transdução de Sinais
10.
Eur Cell Mater ; 35: 350-364, 2018 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-29926464

RESUMO

Tissue engineering has the potential to overcome the limitations of tracheal reconstruction. To tissue-engineer a tracheal cartilage, auricular chondrocytes were encapsulated in a photocurable poly(ethylene glycol)/poly(ε-caprolactone) (PEG/PCL) hydrogel. Chondrogenic genes, including Sox9, Acan and Col2a1, were up-regulated in auricular chondrocytes after 2 weeks of in vitro cultivation in the PEG/PCL hydrogel. Co-cultivation of 70 % auricular chondrocytes and 30 % bone marrow mesenchymal stem cells (BMSCs) accelerated the chondrogenic genes' expression in the PEG/PCL hydrogel. Cartilaginous matrix markers, including proteoglycans and collagen type II, were detected in the chondrocytes-encapsulated PEG/PCL hydrogel after 4 weeks of in vitro cultivation. The higher expression level of cartilaginous matrix markers was observed in the PEG/PCL hydrogel with co-cultivation of 70 % chondrocytes and 30 % BMSCs. After 4 weeks of ectopic cultivation in rabbits, the cylindrical PEG/PCL structure was sustained with the use of a luminal silicon stent. However, without the stent, the construct collapsed under a compression force. No fibrosis or vessel ingrowth were found in the PEG/PCL hydrogel after 4 weeks of ectopic cultivation, whereas the auricular chondrocytes showed proteoglycans' accumulation and collagen type II production. Rabbit auricular chondrocytes could survive and retain chondrogenic ability in the PEG/PCL hydrogel under both in vitro and in vivo conditions. While the PEG/PCL hydrogel did not show sufficient mechanical properties for supporting the cylindrical shape of the construct, the high chondrogenesis level of chondrocytes in the PEG/PCL hydrogel displayed the potential of this material for tracheal tissue engineering.


Assuntos
Condrócitos/citologia , Cartilagem da Orelha/citologia , Hidrogéis/farmacologia , Poliésteres/farmacologia , Polietilenoglicóis/farmacologia , Engenharia Tecidual/métodos , Traqueia/fisiologia , Animais , Células Cultivadas , Condrogênese/efeitos dos fármacos , Condrogênese/genética , Colágeno/metabolismo , Matriz Extracelular/efeitos dos fármacos , Matriz Extracelular/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Modelos Animais , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo , Poliésteres/química , Polietilenoglicóis/química , Proteoglicanas/metabolismo , Coelhos , Vimentina/metabolismo
11.
Water Sci Technol ; 77(1-2): 114-122, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29339610

RESUMO

In this study, we demonstrated that the choice of precursor has a strong effect on the reduction of nitrate (NO3-) using zero-valent copper (Cu0) synthesized by sodium borohydride (NaBH4). Different precursors: CuSO4, CuO, Cu2O, Cu powder, and Cu mesh were used to reduce NO3- at 677 mg-N/L under the reducing conditions of NaBH4. Compared with the prehydrolyzed samples, those prepared without prehydrolysis exhibited lower reduction rates, longer times and higher concentrations of nitrite (NO2-) intermediate. It was found that one-time addition of NaBH4 resulted in higher reduction rate and less NO2- intermediate than two-step addition. Results showed that Cu0 from CuSO4 possessed the smallest particle size (890.9 nm), highest surface area (26.0 m2/g), and highest reaction rate (0.166 min-1). Values of pseudo-first-order constant (kobs) were in the order: CuSO4 > CuO > Cu2O > Cu powder >Cu mesh. However, values of surface area-normalized reaction rate (kSA) were approximately equal. It was proposed that NO3- was reduced to NO2- on Cu0, and then converted to NH4+ and N2, respectively; H2 generated from both NaBH4 hydration and Cu (II) reduction contributed to NO3- reduction as well.


Assuntos
Boroidretos/química , Cobre/química , Nitratos/análise , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Hidrólise , Modelos Teóricos , Nitritos/análise , Óxidos de Nitrogênio/análise , Oxirredução , Tamanho da Partícula , Propriedades de Superfície
12.
Int J Oral Maxillofac Surg ; 47(6): 699-707, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29174861

RESUMO

The aim of this study was to investigate potential biomarkers in human saliva and plasma to aid in the early diagnosis of oral squamous cell carcinoma (OSCC). Saliva and plasma samples obtained from OSCC patients (n=41) and non-oral cancer patients (n=24) were analyzed by Luminex Bead-based Multiplex Assay. Data were analyzed using the non-parametric Mann-Whitney U-test, Kruskal-Wallis test, and receiver operating characteristics curve (ROC) to evaluate the predictive power of 14 biomarkers individually for OSCC diagnosis. The plasma level of IP-10 in early OSCC differed significantly from that in controls. Among the salivary biomarkers, IL-1ß, IL-6, IL-8, MIP-1ß, eotaxin and IFN-γ and TNF-α showed significant differences between OSCC patients and controls. With respect to carcinogenesis, significant differences in plasma levels of eotaxin, G-CSF, and IL-6 were found between OSCC stages III/IV and OSCC stages I/II. The area under the curve (AUC) for OSCC vs. control was greater than 0.7 for plasma IP-10 and saliva IL-1ß, IL-6, IL-8, and TNF-α. The study findings indicate that salivary biomarkers may serve a useful role as a complementary adjunct for the early detection of oral OSCC. With regard to the evaluation of tumour progression, plasma eotaxin, G-CSF, and IL-6 may help in the detection of advanced OSCC. However, the correlation between saliva and plasma biomarkers in OSCC was weak.


Assuntos
Biomarcadores Tumorais/metabolismo , Carcinoma de Células Escamosas/metabolismo , Citocinas/metabolismo , Neoplasias Bucais/metabolismo , Saliva/química , Adulto , Idoso , Biomarcadores Tumorais/sangue , Carcinoma de Células Escamosas/sangue , Carcinoma de Células Escamosas/patologia , Citocinas/sangue , Progressão da Doença , Feminino , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/sangue , Neoplasias Bucais/patologia , Estadiamento de Neoplasias , Fatores de Risco
13.
Clin Pharmacol Ther ; 103(3): 468-476, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-28599060

RESUMO

Sacubitril/valsartan (LCZ696) is indicated for the treatment of patients with heart failure and reduced ejection fraction (HFrEF). Since patients with HFrEF may receive sacubitril/valsartan and sildenafil, both increasing cyclic guanosine monophosphate, the present study evaluated the pharmacokinetic and pharmacodynamic drug interaction potential between sacubitril/valsartan and sildenafil. In this open-label, three-period, single sequence study, patients with mild-to-moderate hypertension (153.8 ± 8.2 mmHg mean systolic blood pressure (SBP)) received a single dose of sildenafil 50 mg, sacubitril/valsartan 400 mg once daily for 5 days, and sacubitril/valsartan and sildenafil coadministration. When coadministered with sildenafil, the AUC and Cmax of valsartan decreased by 29% and 39%, respectively. Coadministration of sacubitril/valsartan and sildenafil resulted in a greater decrease in BP (-5/-4/-4 mmHg mean ambulatory SBP/DBP/MAP (mean arterial pressure)) than with sacubitril/valsartan alone. Both treatments were generally safe and well tolerated in this study; however, the additional BP reduction suggests that sildenafil should be administered cautiously in patients receiving sacubitril/valsartan. Unique identifier: NCT01601470.


Assuntos
Aminobutiratos/farmacologia , Aminobutiratos/farmacocinética , Antagonistas de Receptores de Angiotensina/farmacologia , Antagonistas de Receptores de Angiotensina/farmacocinética , Anti-Hipertensivos/farmacologia , Anti-Hipertensivos/farmacocinética , Hipertensão/tratamento farmacológico , Citrato de Sildenafila/farmacologia , Citrato de Sildenafila/farmacocinética , Tetrazóis/farmacologia , Tetrazóis/farmacocinética , Aminobutiratos/efeitos adversos , Antagonistas de Receptores de Angiotensina/efeitos adversos , Anti-Hipertensivos/efeitos adversos , Fator Natriurético Atrial/urina , Compostos de Bifenilo , Pressão Sanguínea/efeitos dos fármacos , GMP Cíclico/urina , Método Duplo-Cego , Combinação de Medicamentos , Interações Medicamentosas , Humanos , Masculino , Pessoa de Meia-Idade , Citrato de Sildenafila/efeitos adversos , Tetrazóis/efeitos adversos , Valsartana
14.
Am J Transplant ; 18(1): 216-225, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28730633

RESUMO

Immunological requirements for rejection and tolerance induction differ between various organs. While memory CD8+ T cells are considered a barrier to immunosuppression-mediated acceptance of most tissues and organs, tolerance induction after lung transplantation is critically dependent on central memory CD8+ T lymphocytes. Here we demonstrate that costimulation blockade-mediated tolerance after lung transplantation is dependent on programmed cell death 1 (PD-1) expression on CD8+ T cells. In the absence of PD-1 expression, CD8+ T cells form prolonged interactions with graft-infiltrating CD11c+ cells; their differentiation is skewed towards an effector memory phenotype and grafts are rejected acutely. These findings extend the notion that requirements for tolerance induction after lung transplantation differ from other organs. Thus, immunosuppressive strategies for lung transplant recipients need to be tailored based on the unique immunological properties of this organ.


Assuntos
Linfócitos T CD8-Positivos/citologia , Linfócitos T CD8-Positivos/imunologia , Diferenciação Celular , Rejeição de Enxerto/imunologia , Sobrevivência de Enxerto/imunologia , Transplante de Pulmão , Receptor de Morte Celular Programada 1/metabolismo , Aloenxertos , Animais , Rejeição de Enxerto/patologia , Terapia de Imunossupressão , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL
15.
Mol Ther ; 25(8): 1974-1987, 2017 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-28716575

RESUMO

Trauma-induced heterotopic ossification (tHO) is a condition of pathologic wound healing, defined by the progressive formation of ectopic bone in soft tissue following severe burns or trauma. Because previous studies have shown that genetic variants of HO, such as fibrodysplasia ossificans progressiva (FOP), are caused by hyperactivating mutations of the type I bone morphogenetic protein receptor (T1-BMPR) ACVR1/ALK2, studies evaluating therapies for HO have been directed primarily toward drugs for this specific receptor. However, patients with tHO do not carry known T1-BMPR mutations. Here we show that, although BMP signaling is required for tHO, no single T1-BMPR (ACVR1/ALK2, BMPR1a/ALK3, or BMPR1b/ALK6) alone is necessary for this disease, suggesting that these receptors have functional redundancy in the setting of tHO. By utilizing two different classes of BMP signaling inhibitors, we developed a translational approach to treatment, integrating treatment choice with existing diagnostic options. Our treatment paradigm balances either immediate therapy with reduced risk for adverse effects (Alk3-Fc) or delayed therapy with improved patient selection but greater risk for adverse effects (LDN-212854).


Assuntos
Receptores de Proteínas Morfogenéticas Ósseas/genética , Marcação de Genes , Ossificação Heterotópica/etiologia , Ossificação Heterotópica/patologia , Ferimentos e Lesões/complicações , Receptores de Ativinas Tipo I/deficiência , Animais , Anti-Inflamatórios/farmacologia , Biomarcadores , Receptores de Proteínas Morfogenéticas Ósseas Tipo I/deficiência , Técnicas de Inativação de Genes , Predisposição Genética para Doença , Humanos , Ligantes , Macrófagos/metabolismo , Camundongos , Camundongos Knockout , Neutrófilos/metabolismo , Ossificação Heterotópica/prevenção & controle , Inibidores de Proteínas Quinases/farmacologia
16.
Appl Ergon ; 59(Pt A): 460-469, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27890159

RESUMO

This study evaluated the effect of an extension ladder "walk-through" top design on kinetic and kinematic behaviors and the outward destabilizing forces induced on the ladder during transitioning at elevation. Thirty-two male participants performed stepping tasks between a ladder top and a roof at simulated elevation in a surround-screen virtual-reality system. The experimental conditions included a "walk-through" and a standard ladder top section supported on flat and sloped roof surfaces. Three force platforms were placed under the ladder section and in the roof to measure propulsion forces during transitions. A motion measurement system was used to record trunk kinematics. The frictional demand at the virtual ladder base was also calculated. The results indicate that under optimal ladder setup (angle 75.5 °), the frictional demand at the ladder base remains relatively small for all experimental conditions. Also, the "walk through" ladder top eased the ladder-to-roof transitions but not the roof-to-ladder transitions.


Assuntos
Acidentes por Quedas/prevenção & controle , Desenho de Equipamento , Segurança , Adulto , Fenômenos Biomecânicos , Simulação por Computador , Fricção , Humanos , Masculino , Pessoa de Meia-Idade , Análise e Desempenho de Tarefas , Interface Usuário-Computador , Caminhada , Adulto Jovem
17.
Am J Transplant ; 16(10): 3016-3023, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27273836

RESUMO

Ischemia-reperfusion injury-mediated primary graft dysfunction substantially hampers short- and long-term outcomes after lung transplantation. This condition continues to be diagnosed based on oxygen exchange parameters as well as radiological appearance, and therapeutic strategies are mostly supportive in nature. Identifying patients who may benefit from targeted therapy would therefore be highly desirable. Here, we show that C-C chemokine receptor type 2 (CCR2) expression in murine lung transplant recipients promotes monocyte infiltration into pulmonary grafts and mediates graft dysfunction. We have developed new positron emission tomography imaging agents using a CCR2 binding peptide, ECLi1, that can be used to monitor inflammatory responses after organ transplantation. Both 64 Cu-radiolabeled ECL1i peptide radiotracer (64 Cu-DOTA-ECL1i) and ECL1i-conjugated gold nanoclusters doped with 64 Cu (64 CuAuNCs-ECL1i) showed specific detection of CCR2, which is upregulated during ischemia-reperfusion injury after lung transplantation. Due to its fast pharmacokinetics, 64 Cu-DOTA-ECL1i functioned efficiently for rapid and serial imaging of CCR2. The multivalent 64 CuAuNCs-ECL1i with extended pharmacokinetics is favored for long-term CCR2 detection and potential targeted theranostics. This imaging may be applicable for diagnostic and therapeutic purposes for many immune-mediated diseases.


Assuntos
Transplante de Pulmão/métodos , Imagem Molecular/métodos , Receptores CCR2/fisiologia , Traumatismo por Reperfusão/diagnóstico por imagem , Animais , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Monócitos/imunologia , Monócitos/metabolismo , Fragmentos de Peptídeos/metabolismo , Tomografia por Emissão de Pósitrons/métodos , Traumatismo por Reperfusão/imunologia , Traumatismo por Reperfusão/metabolismo , Transdução de Sinais
18.
Proc Natl Acad Sci U S A ; 113(3): E338-47, 2016 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-26721400

RESUMO

Pathologic extraskeletal bone formation, or heterotopic ossification (HO), occurs following mechanical trauma, burns, orthopedic operations, and in patients with hyperactivating mutations of the type I bone morphogenetic protein receptor ACVR1 (Activin type 1 receptor). Extraskeletal bone forms through an endochondral process with a cartilage intermediary prompting the hypothesis that hypoxic signaling present during cartilage formation drives HO development and that HO precursor cells derive from a mesenchymal lineage as defined by Paired related homeobox 1 (Prx). Here we demonstrate that Hypoxia inducible factor-1α (Hif1α), a key mediator of cellular adaptation to hypoxia, is highly expressed and active in three separate mouse models: trauma-induced, genetic, and a hybrid model of genetic and trauma-induced HO. In each of these models, Hif1α expression coincides with the expression of master transcription factor of cartilage, Sox9 [(sex determining region Y)-box 9]. Pharmacologic inhibition of Hif1α using PX-478 or rapamycin significantly decreased or inhibited extraskeletal bone formation. Importantly, de novo soft-tissue HO was eliminated or significantly diminished in treated mice. Lineage-tracing mice demonstrate that cells forming HO belong to the Prx lineage. Burn/tenotomy performed in lineage-specific Hif1α knockout mice (Prx-Cre/Hif1α(fl:fl)) resulted in substantially decreased HO, and again lack of de novo soft-tissue HO. Genetic loss of Hif1α in mesenchymal cells marked by Prx-cre prevents the formation of the mesenchymal condensations as shown by routine histology and immunostaining for Sox9 and PDGFRα. Pharmacologic inhibition of Hif1α had a similar effect on mesenchymal condensation development. Our findings indicate that Hif1α represents a promising target to prevent and treat pathologic extraskeletal bone.


Assuntos
Subunidade alfa do Fator 1 Induzível por Hipóxia/antagonistas & inibidores , Ossificação Heterotópica/genética , Ossificação Heterotópica/prevenção & controle , Ferimentos e Lesões/complicações , Receptores de Ativinas Tipo I/metabolismo , Tecido Adiposo/efeitos dos fármacos , Tecido Adiposo/metabolismo , Animais , Queimaduras/complicações , Queimaduras/genética , Condrogênese/efeitos dos fármacos , Condrogênese/genética , Modelos Animais de Doenças , Redes Reguladoras de Genes/efeitos dos fármacos , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Integrases/metabolismo , Medições Luminescentes , Células-Tronco Mesenquimais/efeitos dos fármacos , Camundongos Knockout , Modelos Biológicos , Compostos de Mostarda/farmacologia , Ossificação Heterotópica/diagnóstico por imagem , Ossificação Heterotópica/tratamento farmacológico , Fenilpropionatos/farmacologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/metabolismo , Fatores de Transcrição SOX9/metabolismo , Transdução de Sinais/efeitos dos fármacos , Sirolimo/farmacologia , Tendões/efeitos dos fármacos , Tendões/patologia , Tendões/cirurgia , Tenotomia , Regulação para Cima/efeitos dos fármacos , Cicatrização/efeitos dos fármacos , Ferimentos e Lesões/patologia , Microtomografia por Raio-X
19.
Am J Transplant ; 16(4): 1079-85, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26614734

RESUMO

De novo induction of organized lymphoid aggregates at nonlymphoid sites has been observed in many chronic inflammatory conditions where foreign antigens such as infectious agents, autoantigens or alloantigens, persist. The prevailing opinion in the field of transplantation is that lymphoid neogenesis within allografts is detrimental to the establishment of immune tolerance. These structures, commonly referred to as tertiary lymphoid organs (TLOs), are thought to contribute to graft rejection by generating and propagating local alloimmune responses. However, recent studies have shown that TLOs rich in regulatory Foxp3(+) cells are present in long-term accepting allografts. The notion that TLOs can contribute to the local downregulation of immune responses has been corroborated in other chronic inflammation models. These findings suggest that contrary to previous suggestions that the induction of TLOs in allografts is necessarily harmful, the induction of "tolerogenic" TLOs may prove advantageous. In this review, we discuss our current understanding of how TLOs are induced and how they regulate immune responses with a particular focus on alloimmunity.


Assuntos
Rejeição de Enxerto/imunologia , Tolerância Imunológica/imunologia , Tecido Linfoide/imunologia , Transplante de Órgãos , Aloenxertos , Animais , Humanos
20.
Genet Mol Res ; 14(4): 17028-33, 2015 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-26681050

RESUMO

Despite sharing a similar genetic abnormality, patients with core binding factor acute myeloid leukemia (CBF-AML), which is characterized by the presence of t(8;21) or inv(16)/t(16;16), show heterogeneous survival. Other molecular or cytogenetic factors are supposed to have an impact on the prognosis. We enrolled 24 CBF-AML patients to determine the impact of cytogenetic abnormality, and c-KIT, FLT3, NPM1, and CEBPA mutations on the prognosis. Only three patients had the c-KIT mutation (3/24, 12.5%) and one had the FLT3 mutation. However, over half of the patients (14/24) harbored additional cytogenetic changes, including ten with loss of sexual chromosomes (LOS) [all in the t(8;21) group], and six had additional abnormalities (two cases had both LOS and additional abnormalities). From this small-number study, no association was found between c-KIT mutation and survival and relapse rate. However, additional chromosome abnormalities had a significant association with relapse of the disease (P = 0.027). Stem cell transplant had a trend of benefitting patients after relapse (P = 0.065). This implies that chromosome abnormalities occur in CBF-AML and might take part in the heterogeneous nature of CBF-AML.


Assuntos
Aberrações Cromossômicas , Fatores de Ligação ao Core/genética , Leucemia Mieloide Aguda/genética , Adulto , Idoso , Feminino , Humanos , Leucemia Mieloide Aguda/mortalidade , Masculino , Pessoa de Meia-Idade , Mutação , Nucleofosmina , Prognóstico , Proteínas Proto-Oncogênicas c-kit/genética , Adulto Jovem
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