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1.
Int J Mol Sci ; 23(16)2022 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-36012474

RESUMO

The formation of pathological bone deposits within soft tissues, termed heterotopic ossification (HO), is common after trauma. However, the severity of HO formation varies substantially between individuals, from relatively isolated small bone islands through to extensive soft tissue replacement by bone giving rise to debilitating symptoms. The aim of this study was to identify novel candidate therapeutic molecular targets for severe HO. We conducted a genome-wide scan in men and women with HO of varying severity following hip replacement for osteoarthritis. HO severity was dichotomized as mild or severe, and association analysis was performed with adjustment for age and sex. We next confirmed expression of the gene encoded by the lead signal in human bone and in primary human mesenchymal stem cells. We then examined the effect of gene knockout in a murine model of osseous trans-differentiation, and finally we explored transcription factor phosphorylation in key pathways perturbed by the gene. Ten independent signals were suggestively associated with HO severity, with KIF26B as the lead. We subsequently confirmed KIF26B expression in human bone and upregulation upon BMP2-induced osteogenic differentiation in primary human mesenchymal stem cells, and also in a rat tendo-Achilles model of post-traumatic HO. CRISPR-Cas9 mediated knockout of Kif26b inhibited BMP2-induced Runx2, Sp7/Osterix, Col1A1, Alp, and Bglap/Osteocalcin expression and mineralized nodule formation in a murine myocyte model of osteogenic trans-differentiation. Finally, KIF26B deficiency inhibited ERK MAP kinase activation during osteogenesis, whilst augmenting p38 and SMAD 1/5/8 phosphorylation. Taken together, these data suggest a role for KIF26B in modulating the severity of post-traumatic HO and provide a potential novel avenue for therapeutic translation.


Assuntos
Cinesinas , Ossificação Heterotópica , Osteogênese , Animais , Diferenciação Celular/genética , Feminino , Humanos , Cinesinas/genética , Masculino , Camundongos , Ossificação Heterotópica/genética , Ossificação Heterotópica/metabolismo , Osteocalcina/metabolismo , Osteogênese/genética , Ratos
2.
Rev Sci Instrum ; 90(11): 114503, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31779445

RESUMO

We present a new noncontact methodology to excite and detect ultrasonic waves in rocks under in situ pressure and temperature conditions. Optical windows in the side of a pressure vessel allow the passage of a laser source and a receiver for noncontact laser ultrasonic measurements. A heating mantle controls the temperature, and a rotational stage inside the vessel makes it possible to obtain measurements as a function of angle. This methodology is the first to combine the advantages of laser ultrasonics (LUS) over traditional transducer methods with measurements under in situ pressure and temperature conditions. These advantages include the absence of mechanical coupling, small sampling area, and broadband recordings of absolute displacement. After describing the experimental setup, we present control experiments to validate the accuracy of this new system for acquiring rock physics data. Densely sampled rotational scans performed on an Alpine Fault ultramylonite rock reveal a decrease in P-wave anisotropy from 62% at atmospheric pressure to 36% at 16 MPa. This result highlights the importance of performing rock physics measurements under in situ confining stress and demonstrates the advantages of the methodology for investigating anisotropy. In addition, a 5.6% decrease in the P-wave velocity of the ultramylonite sample between 20 °C and 100 °C at a constant 10 MPa confining stress demonstrates the capability of this new methodology for acquiring data under both in situ pressure and temperature conditions. This new methodology opens the door for probing the pressure and temperature dependence of the elastic properties of rocks and other materials using LUS techniques.

3.
Eur J Surg Oncol ; 45(12): 2241-2250, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31262600

RESUMO

Cancer predisposition genes are rare mutations that confer a high risk of cancer. For many hereditary cancer syndromes, risk reducing surgery is the single most effective strategy for preventing cancer, but it is irreversible. It has recently attracted significant media attention, following celebrity endorsement, which has led to a perceived lack of ill-effect and guaranteed successful outcome by the general public. Given these high expectations for risk-reducing surgery, a systematic review was performed to evaluate the reported complications for patients undergoing risk-reducing surgery. A systematic review of MEDLINE, EMBASE, CINAHL, AMED and PubMed work was conducted using PRISMA for risk-reducing surgery in adults for cancer predisposition genes in breast, ovary, stomach, thyroid and colorectal. The main outcomes were 30-day morbidity and mortality associated with these procedures. Twenty-five studies (2366 patients) reporting on outcomes following risk-reducing surgery were analysed, 5 related to breast and/or ovary, 3 for stomach, 2 for thyroid and the remaining 15 were colorectal. Risk-reducing surgery was uniformly associated with 30-day morbidity, particularly for breast (variable rates), colorectal (311/1400 patients (22%)) and stomach (35/75 patients (47%)) surgery. The 30-day morbidity for ovarian risk-reducing surgery was relatively low (11/244 patients (5%)). There was also a small mortality risk associated with colorectal (1/1400 patients) and stomach (1/75 patients). This study provides an important and necessary summary of the current data, enabling clinicians to better inform patients of the associated short and long-term outcomes in risk-reducing surgery for cancer predisposition genes.


Assuntos
Síndromes Neoplásicas Hereditárias/prevenção & controle , Síndromes Neoplásicas Hereditárias/cirurgia , Procedimentos Cirúrgicos Profiláticos , Comportamento de Redução do Risco , Humanos , Complicações Pós-Operatórias
4.
Surg Oncol ; 29: 53-63, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31196494

RESUMO

Retroperitoneal sarcomas (RPS) are rare mesenchymal tumours. Their rarity challenges our ability to understand expected outcomes. The aim of this systematic review was to examine 30-day morbidity and mortality, overall survival rates and prognostic predictors from population-based studies for patients undergoing curative resection for primary RPS. A systematic literature review of EMBASE, MEDLINE, PUBMED and the Cochrane library was performed using PRISMA for population-based studies reporting from nationally registered databases on primary RPS surgical resections in adults. The main outcomes evaluated were 30-day morbidity and mortality and overall survival rates. The use of additional treatment modalities and predictors of overall survival were also examined. Fourteen studies (n = 12 834 patients) reporting from 3 national databases, (Surveillance, Epidemiology and End Results (SEER), the United States National Cancer Database (US NCDB) and the American College of Surgeons' National Surgical Quality Improvement Program (ACS NSQIP)) were analysed. The reported overall 30-day morbidity and mortality were 23% (n = 191/846) and 3% (n = 278/10 181) respectively. Reported use of perioperative radiotherapy was 28%. No study reported loco-regional recurrence rates. Overall reported 5-year survival ranged from 52% to 62%. Independent predictors of overall survival were age of the patient, resection margin, tumour grade and size, histological subtype and receipt of radiotherapy. This review of population-based data demonstrated relatively low 30-day morbidity rates in patients undergoing curative surgical resections for primary RPS. Thirty-day mortality rates were similar to other abdominal tumour groups. There remains a paucity of data reporting recurrence rates, however 5-year survival rates ranged from 52 to 62%.


Assuntos
Bases de Dados Factuais , Recidiva Local de Neoplasia/diagnóstico , Complicações Pós-Operatórias , Neoplasias Retroperitoneais/cirurgia , Sarcoma/cirurgia , Procedimentos Cirúrgicos Operatórios/mortalidade , Humanos , Incidência , Recidiva Local de Neoplasia/epidemiologia , Prognóstico , Neoplasias Retroperitoneais/epidemiologia , Neoplasias Retroperitoneais/patologia , Sarcoma/epidemiologia , Sarcoma/patologia , Taxa de Sobrevida
5.
Genes (Basel) ; 9(9)2018 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-30223528

RESUMO

It is estimated that 30% of all genes in the mammalian cells are regulated by microRNA (miRNAs). The most relevant miRNAs in a cellular context are not necessarily those with the greatest change in expression levels between healthy and diseased tissue. Differentially expressed (DE) miRNAs that modulate a large number of messenger RNA (mRNA) transcripts ultimately have a greater influence in determining phenotypic outcomes and are more important in a global biological context than miRNAs that modulate just a few mRNA transcripts. Here, we describe the development of a tool, "miRmapper", which identifies the most dominant miRNAs in a miRNA⁻mRNA network and recognizes similarities between miRNAs based on commonly regulated mRNAs. Using a list of miRNA⁻target gene interactions and a list of DE transcripts, miRmapper provides several outputs: (1) an adjacency matrix that is used to calculate miRNA similarity utilizing the Jaccard distance; (2) a dendrogram and (3) an identity heatmap displaying miRNA clusters based on their effect on mRNA expression; (4) a miRNA impact table and (5) a barplot that provides a visual illustration of this impact. We tested this tool using nonmetastatic and metastatic bladder cancer cell lines and demonstrated that the most relevant miRNAs in a cellular context are not necessarily those with the greatest fold change. Additionally, by exploiting the Jaccard distance, we unraveled novel cooperative interactions between miRNAs from independent families in regulating common target mRNAs; i.e., five of the top 10 miRNAs act in synergy.

10.
Genes (Basel) ; 8(10)2017 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-29027980

RESUMO

Ubiquitous exposure to bisphenol A (BPA), an endocrine disruptor (ED), has raised concerns for both human and ecosystem health. Epigenetic factors, including microRNAs (miRNAs), are key regulators of gene expression during cancer. The effect of BPA exposure on the zebrafish epigenome remains poorly characterized. Zebrafish represents an excellent model to study cancer as the organism develops a disease that resembles human cancer. Using zebrafish as a systems toxicology model, we hypothesized that chronic BPA-exposure impacts the miRNome in adult zebrafish and establishes an epigenome more susceptible to cancer development. After a 3 week exposure to 100 nM BPA, RNA from the liver was extracted to perform high throughput mRNA and miRNA sequencing. Differential expression (DE) analyses comparing BPA-exposed to control specimens were performed using established bioinformatics pipelines. In the BPA-exposed liver, 6188 mRNAs and 15 miRNAs were differently expressed (q ≤ 0.1). By analyzing human orthologs of the DE zebrafish genes, signatures associated with non-alcoholic fatty liver disease (NAFLD), oxidative phosphorylation, mitochondrial dysfunction and cell cycle were uncovered. Chronic exposure to BPA has a significant impact on the liver miRNome and transcriptome in adult zebrafish with the potential to cause adverse health outcomes including cancer.

12.
J Perioper Pract ; 27(12): 292-295, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29328791

RESUMO

Orthopaedic theatre can be noisy. Fifty percent of orthopaedic theatre staff have features of noise-induced hearing loss (NIHL). In this study, decibel (dB) levels were recorded in 17 total knee replacements (TKRs) and 11 total hip replacements (THRs). Noise levels reached 105.6dB(A) using a hammer and 97.9dB(A) with an oscillating saw. Exposure to levels above 90dB (which occurred in every case) even for short time periods is proven to cause irreversible loss of hearing. Tools used in orthopaedic theatre produce impulse noises that can cause NIHL. Further investigation is required.


Assuntos
Artroplastia de Quadril , Artroplastia do Joelho , Perda Auditiva Provocada por Ruído/etiologia , Exposição Ocupacional/análise , Artroplastia de Quadril/instrumentação , Artroplastia do Joelho/instrumentação , Humanos , Ruído/efeitos adversos , Exposição Ocupacional/efeitos adversos , Equipamentos Ortopédicos , Ortopedia
13.
Nanoscale Horiz ; 1(1): 60-63, 2016 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-32260603

RESUMO

We have produced silver glyconanoparticles for the sensitive (56 ng mL -1), low volume and rapid detection of cholera toxin B-subunit (CTB) in synthetic freshwater (simulating the ion compositions of natural waters in which CTB could be found). This is achieved by monitoring the changes in surface enhanced Raman scattering (SERS) intensity of a Raman reporter bound to the glyconanoparticle surface. The particles selectively aggregate upon interaction with CTB, causing an increase in the measured SERS signal. The particles are designed to mimic the interactions involving the cell surface GM1 ganglioside and CTB. This is achieved by using a combination of polyethylene glycol linkers terminated with either galactose or sialic acid.

14.
Anal Chem ; 86(10): 4775-82, 2014 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-24842517

RESUMO

Lectin-functionalized silver nanoparticles have been successfully designed for use as molecular imaging agents to investigate carbohydrate-lectin interactions at the surface of mammalian cells, using surface-enhanced Raman scattering (SERS). Carbohydrate-lectin interactions are key to many cellular processes and are responsible for controlling an array of cellular interactions. In this study, lectin-functionalized silver nanoparticles were used to detect the expression of carbohydrate species at the cellular interface. The carbohydrate-lectin interactions were demonstrated using three different lectin species for three distinct cell types. Due to the known difference between the expressions of glycans in cancerous versus noncancerous cells of the same origin, this approach has been expanded to study both cancerous and noncancerous prostate cells. This has been achieved via confocal SERS mapping of the expression of the key glycan, sialic acid, on the surface of each of these cell types. In achieving such discrimination, a novel method has been created by which glycan expression can be reproducibly monitored. Comparative studies were performed using both fluorescence and SERS. SERS provided an increased discrimination over fluorescence when analyzing cell subsets to discriminate between cancerous and noncancerous cells. The success of this method means that it could be used to complement the current gold standard histopathological techniques.


Assuntos
Nanopartículas Metálicas/química , Neoplasias/metabolismo , Polissacarídeos/biossíntese , Polissacarídeos/química , Prata/química , Animais , Células CHO , Carboidratos/química , Linhagem Celular Tumoral , Cricetinae , Cricetulus , Humanos , Lectinas/química , Espalhamento de Radiação , Análise Espectral Raman
15.
Chem Commun (Camb) ; 49(1): 30-2, 2013 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-23114655

RESUMO

An on/off SERS aggregation system has been designed to investigate carbohydrate-lectin interactions. Detection of the lectin ConA was achieved at pico molar levels. Discrimination was also demonstrated between two different carbohydrate moieties demonstrating the specific interaction between the carbohydrate and specific protein present.


Assuntos
Concanavalina A/química , Lectinas/química , Nanopartículas/química , Carboidratos/química , Concanavalina A/metabolismo , Galactose/química , Lactose/química , Lectinas/metabolismo , Análise Espectral Raman
17.
Gut ; 59(7): 926-33, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20581241

RESUMO

OBJECTIVE: To evaluate immunosurveillance/editing in colorectal cancer. DESIGN: Transformation stimulates the production of interferon gamma (IFNgamma) which signals via the IFNgamma receptor (IFNGR1) on tumours. This results in stimulation of nuclear STAT1 (nSTAT1), inhibition of tumour growth and upregulation of major histocompatibility complex (MHC) while promoting T cell extravasation. In contrast, downregulation of MHC class I by allele loss results in loss of T cell recognition. A tissue microarray of 462 colorectal tumours with mean follow-up of 42 months (range 1-116) was stained by immunohistochemistry for markers which predict immunosurveillance/editing. RESULTS: The presence of a high level of intratumoral T cells (ITTC) correlated with improved survival compared with a low level of ITTC, with a mean difference in survival of 16.3 months (p=0.006). There was a direct correlation between nSTAT1 expression and ITTC (p<0.001). Patients whose tumours had a high level of ITTC and nSTAT1 survived 20 months longer than those whose tumours had a low level of ITTC and no nSTAT1. A strong correlation was seen between ITTC and MHC class I expression (p=0.0002). A mean survival advantage of 26.1 months was seen in patients whose tumours had strong MHC I expression and high levels of ITTC over those who had weak MHC I and low levels of ITTC (log-rank test=12.023, p=0.034). Both MHC I and ITTC are independent predictors of good survival. CONCLUSIONS: ITTC, nSTAT1 and strong MHC class I expression on tumours identify patients with improved survival and an intact tumour immune system that may benefit from immunotherapy. Conversely, loss of these markers identifies patients whose tumours have escaped immunosurveillance and are unlikely to benefit from immunotherapy.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias Colorretais/imunologia , Neoplasias Colorretais/metabolismo , Linfócitos do Interstício Tumoral/imunologia , Fator de Transcrição STAT1/metabolismo , Subpopulações de Linfócitos T/imunologia , Idoso , Neoplasias Colorretais/patologia , Neoplasias Colorretais/cirurgia , Feminino , Antígenos de Histocompatibilidade Classe I/metabolismo , Humanos , Masculino , Invasividade Neoplásica , Proteínas de Neoplasias/metabolismo , Estadiamento de Neoplasias , Prognóstico , Receptores de Interferon/metabolismo , Análise de Sobrevida , Receptor de Interferon gama
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