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1.
mBio ; : e0245823, 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37905801

RESUMO

The E6 protein encoded by the murine papillomavirus (MmuPV1) is essential for MmuPV1-induced skin disease. Our previous work has identified a number of cellular interacting partners of MmuPV1 E6 and E7 through affinity purification/mass spectrometry analysis. These studies revealed that MmuPV1 E6 potently inhibits keratinocyte differentiation through multiple molecular mechanisms including inhibition of NOTCH and TGF-ß signaling. Here, we report that MmuPV1 E6 has additional important oncogenic activities when expressed in its natural host cells, mouse keratinocytes, including increasing proliferation, overcoming density-mediated growth arrest, and proliferation under conditions of limited supply of growth factors. Unbiased proteomic/transcriptomic analyses of mouse keratinocytes expressing MmuPV1 E6 substantiated its effect on these cellular processes and divulged that some of these effects may be mediated in part through it upregulating E2F activity. Our analyses also revealed that MmuPV1 E6 may alter other cancer hallmarks including evasion of growth suppressors, inhibition of immune response, resistance to cell death, and alterations in DNA damage response. Collectively, our results suggest that MmuPV1 E6 is a major driver of multiple hallmarks of cancer in MmuPV1's natural host cells, mouse keratinocytes.IMPORTANCEThe Mus musculus papillomavirus 1 (MmuPV1) E6 and E7 proteins are required for MmuPV1-induced disease. Our understanding of the activities of MmuPV1 E6 has been based on affinity purification/mass spectrometry studies where cellular interacting partners of MmuPV1 E6 were identified, and these studies revealed that MmuPV1 E6 can inhibit keratinocyte differentiation through multiple mechanisms. We report that MmuPV1 E6 encodes additional activities including the induction of proliferation, resistance to density-mediated growth arrest, and decreased dependence on exogenous growth factors. Proteomic and transcriptomic analyses provided evidence that MmuPV1 E6 increases the expression and steady state levels of a number of cellular proteins that promote cellular proliferation and other hallmarks of cancer. These results indicate that MmuPV1 E6 is a major driver of MmuPV1-induced pathogenesis.

2.
PLoS Pathog ; 19(4): e1011215, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-37036883

RESUMO

Human papillomaviruses (HPVs) contribute to approximately 5% of all human cancers. Species-specific barriers limit the ability to study HPV pathogenesis in animal models. Murine papillomavirus (MmuPV1) provides a powerful tool to study the roles of papillomavirus genes in pathogenesis arising from a natural infection. We previously identified Protein Tyrosine Phosphatase Non-Receptor Type 14 (PTPN14), a tumor suppressor targeted by HPV E7 proteins, as a putative cellular target of MmuPV1 E7. Here, we confirmed the MmuPV1 E7-PTPN14 interaction. Based on the published structure of the HPV18 E7/PTPN14 complex, we generated a MmuPV1 E7 mutant, E7K81S, that was defective for binding PTPN14. Wild-type (WT) and E7K81S mutant viral genomes replicated as extrachromosomal circular DNAs to comparable levels in mouse keratinocytes. E7K81S mutant virus (E7K81S MmuPV1) was generated and used to infect FoxN/Nude mice. E7K81S MmuPV1 caused neoplastic lesions at a frequency similar to that of WT MmuPV1, but the lesions arose later and were smaller than WT-induced lesions. The E7K81S MmuPV1-induced lesions also had a trend towards a less severe grade of neoplastic disease. In the lesions, E7K81S MmuPV1 supported the late (productive) stage of the viral life cycle and promoted E2F activity and cellular DNA synthesis in suprabasal epithelial cells to similar degrees as WT MmuPV1. There was a similar frequency of lateral spread of infections among mice infected with E7K81S or WT MmuPV1. Compared to WT MmuPV1-induced lesions, E7K81S MmuPV1-induced lesions had a significant expansion of cells expressing differentiation markers, Keratin 10 and Involucrin. We conclude that an intact PTPN14 binding site is necessary for MmuPV1 E7's ability to contribute to papillomavirus-induced pathogenesis and this correlates with MmuPV1 E7 causing a delay in epithelial differentiation, which is a hallmark of papillomavirus-induced neoplasia.


Assuntos
Neoplasias , Proteínas Oncogênicas Virais , Infecções por Papillomavirus , Dermatopatias , Animais , Humanos , Camundongos , Diferenciação Celular , Camundongos Nus , Proteínas Oncogênicas Virais/metabolismo , Papillomaviridae/genética , Proteínas E7 de Papillomavirus/genética , Proteínas E7 de Papillomavirus/metabolismo , Infecções por Papillomavirus/genética , Ligação Proteica , Proteínas Tirosina Fosfatases não Receptoras/genética
3.
ACS Appl Mater Interfaces ; 15(1): 677-683, 2023 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-36562661

RESUMO

Naringin, a natural product, can be used as a therapeutic agent due to its low systemic toxicity and negligible adverse effect. However, due to its hydrophobic nature and thereby low solubility, high-dose treatment is required when used for human therapy. Herein, we demonstrate the employment of a metal-organic framework (MOF) as a nontoxic loading carrier to encapsulate naringin, and the afforded nairngin@MOF composite can serve as a multifunctional bioplatform capable of treating Gram-positive bacteria and certain cancers by slowly and progressively releasing the encapsulated naringin as well as improving and modulating immune system functions through synergy between naringin and the MOF.


Assuntos
Flavanonas , Estruturas Metalorgânicas , Neoplasias , Humanos , Estruturas Metalorgânicas/química , Solubilidade
4.
Microbiol Spectr ; 11(1): e0335122, 2023 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-36472465

RESUMO

Mechanical cleaning remains the standard of care for maintaining oral hygiene. However, mechanical cleaning is often augmented with active therapeutics that further promote oral health. A dentifrice, consisting of the "Dual Zinc plus Arginine" (DZA) technology, was found to be effective at controlling bacteria using in vitro laboratory studies, translating to clinical efficacy to deliver plaque and gingivitis reduction benefits. Here, we used biophysical analyses and confocal laser scanning microscopy to understand how a DZA dentifrice impacted the mechanical properties of dental plaque biofilms and determine if changes to biofilm rheology enhanced the removal of dental plaque. Using both uniaxial mechanical indentation and an adapted rotating-disc rheometry assay, it was found that DZA treatment compromised biofilm mechanical integrity, resulting in the biofilm being more susceptible to removal by shear forces compared to treatment with either arginine or zinc alone. Confocal laser scanning microscopy revealed that DZA treatment reduced the amount of extracellular polymeric slime within the biofilm, likely accounting for the reduced mechanical properties. We propose a model where arginine facilitates the entry of zinc into the biofilm, resulting in additive effects of the two activities toward dental plaque biofilms. Together, our results support the use of a dentifrice containing Dual Zinc plus Arginine as part of daily oral hygiene regimens. IMPORTANCE Mechanical removal of dental plaque is augmented with therapeutic compounds to promote oral health. A dentifrice containing the ingredients zinc and arginine has shown efficacy at reducing dental plaque both in vitro and in vivo. However, how these active compounds interact together to facilitate dental plaque removal is unclear. Here, we used a combination of biophysical analyses and microscopy to demonstrate that combined treatment with zinc and arginine targets the matrix of dental plaque biofilms, which destabilized the mechanical integrity of these microbial communities, making them more susceptible to removal by shear forces.


Assuntos
Placa Dentária , Dentifrícios , Humanos , Dentifrícios/farmacologia , Dentifrícios/uso terapêutico , Arginina , Zinco/farmacologia , Placa Dentária/tratamento farmacológico , Biofilmes
5.
Viruses ; 14(10)2022 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-36298698

RESUMO

Human papillomaviruses (HPVs) cause a substantial amount of human disease from benign disease such as warts to malignant cancers including cervical carcinoma, head and neck cancer, and non-melanoma skin cancer. Our ability to model HPV-induced malignant disease has been impeded by species specific barriers and pre-clinical animal models have been challenging to develop. The recent discovery of a murine papillomavirus, MmuPV1, that infects laboratory mice and causes the same range of malignancies caused by HPVs provides the papillomavirus field the opportunity to test mechanistic hypotheses in a genetically manipulatable laboratory animal species in the context of natural infections. The E6 and E7 proteins encoded by high-risk HPVs, which are the HPV genotypes associated with human cancers, are multifunctional proteins that contribute to HPV-induced cancers in multiple ways. In this review, we describe the known activities of the MmuPV1-encoded E6 and E7 proteins and how those activities relate to the activities of HPV E6 and E7 oncoproteins encoded by mucosal and cutaneous high-risk HPV genotypes.


Assuntos
Alphapapillomavirus , Proteínas Oncogênicas Virais , Infecções por Papillomavirus , Neoplasias do Colo do Útero , Feminino , Humanos , Camundongos , Animais , Proteínas Oncogênicas Virais/genética , Proteínas Oncogênicas Virais/metabolismo , Proteínas E7 de Papillomavirus/genética , Proteínas E7 de Papillomavirus/metabolismo , Alphapapillomavirus/genética , Papillomaviridae/genética , Papillomaviridae/metabolismo
6.
Clin Orthop Relat Res ; 480(10): 1912-1925, 2022 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-35767813

RESUMO

BACKGROUND: Dual-mobility cups in THA were designed to reduce prosthesis instability and the subsequent risk of revision surgery in high-risk patients, such as those with hip fractures. However, there are limited data from clinical studies reporting a revision benefit of dual-mobility over conventional THA. Collaboration between anthroplasty registries provides an opportunity to describe international practice variation and compare between-country, all-cause revision rates for dual-mobility and conventional THA. QUESTIONS/PURPOSES: We summarized observational data from multiple arthroplasty registries for patients receiving either a dual-mobility or conventional THA to ask: (1) Is dual-mobility use associated with a difference in risk of all-cause revision surgery compared with conventional THA? (2) Are there specific patient characteristics associated with dual-mobility use in the hip fracture population? (3) Has the use of dual-mobility constructs changed over time in patients receiving a THA for hip fracture? METHODS: Six member registries of the International Society of Arthroplasty Registries (from Australia, Denmark, Sweden, the Netherlands, the United Kingdom, and the United States) provided custom aggregate data reports stratified by acetabular cup type (dual-mobility or conventional THA) in primary THA for hip fracture between January 1, 2002, and December 31, 2019; surgical approach; and patient demographic data (sex, mean age, American Society of Anesthesiologists class, and BMI). The cumulative percent revision and mortality were calculated for each registry. To determine a global hazard ratio of all-cause revision for dual-mobility compared with conventional THA designs, we used a pseudoindividual patient data approach to pool Kaplan-Meier prosthesis revision data from each registry and perform a meta-analysis. The pseudoindividual patient data approach is a validated technique for meta-analysis of aggregate time-to-event survival data, such as revision surgery, from multiple sources. Data were available for 15,024 dual-mobility THAs and 97,200 conventional THAs performed for hip fractures during the study period. RESULTS: After pooling of complete Kaplan-Meier survival data from all six registries, the cumulative percent revision for conventional THA was 4.3% (95% confidence interval [CI] 4.2% to 4.5%) and 4.7% (95% CI 4.3% to 5.3%) for dual-mobility THA at 5 years. We did not demonstrate a lower risk of all-cause revision for patients receiving dual-mobility over conventional THA designs for hip fracture in the meta-analysis once between-registry differences were adjusted for (HR 0.96 [95% CI 0.86 to 1.06]). A lower proportion of dual-mobility procedures were revised for dislocation than conventional THAs (0.9% versus 1.4%) but a higher proportion were revised for infection (1.2% versus 0.8%). In most registries, a greater proportion of dual-mobility THA patients were older, had more comorbidities, and underwent a posterior approach compared with conventional THA (p < 0.001). The proportion of dual-mobility THA used to treat hip fractures increased in each registry over time and constituted 21% (2438 of 11,874) of all THA procedures in 2019. CONCLUSION: The proportion of dual-mobility THAs in patients with hip fractures increased over time, but there was large variation in use across countries represented here. Dual-mobility cups were not associated with a reduction in the overall risk of revision surgery in patients with hip fractures. A randomized controlled trial powered to detect the incidence of dislocation and subsequent revision surgery is required to clarify the efficacy of dual-mobility cups to treat hip fractures. LEVEL OF EVIDENCE: Level III, therapeutic study.


Assuntos
Artroplastia de Quadril , Fraturas do Colo Femoral , Fraturas do Quadril , Prótese de Quadril , Artroplastia de Quadril/efeitos adversos , Artroplastia de Quadril/métodos , Fraturas do Colo Femoral/etiologia , Fraturas do Quadril/etiologia , Prótese de Quadril/efeitos adversos , Humanos , Desenho de Prótese , Falha de Prótese , Ensaios Clínicos Controlados Aleatórios como Assunto , Sistema de Registros , Reoperação/efeitos adversos , Fatores de Risco
7.
Bone Jt Open ; 3(5): 398-403, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35535505

RESUMO

AIMS: This study aims to estimate economic outcomes associated with 30-day deep surgical site infection (SSI) from closed surgical wounds in patients with lower limb fractures following major trauma. METHODS: Data from the Wound Healing in Surgery for Trauma (WHiST) trial, which collected outcomes from 1,547 adult participants using self-completed questionnaires over a six-month period following major trauma, was used as the basis of this empirical investigation. Associations between deep SSI and NHS and personal social services (PSS) costs (£, 2017 to 2018 prices), and between deep SSI and quality-adjusted life years (QALYs), were estimated using descriptive and multivariable analyses. Sensitivity analyses assessed the impact of uncertainty surrounding components of the economic analyses. RESULTS: Compared to participants without deep SSI, those with deep SSI had higher mean adjusted total NHS and PSS costs (adjusted mean difference £1,577 (95% confidence interval (CI) -951 to 4,105); p = 0.222), and lower mean adjusted QALYs (adjusted mean difference -0.015 (95% CI -0.032 to 0.002); p = 0.092) over six months post-injury, but this difference was not statistically significant. The results were robust to the sensitivity analyses performed. CONCLUSION: This study found worse economic outcomes during the first six months post-injury in participants who experience deep SSI following orthopaedic surgery for major trauma to the lower limb. However, the increase in cost associated with deep SSI was less than previously reported in the orthopaedic trauma literature. Cite this article: Bone Jt Open 2022;3(5):398-403.

8.
PLoS Pathog ; 18(4): e1010453, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35472072

RESUMO

Humans are infected with two types of EBV (Type 1 (T1) and Type 2 (T2)) that differ substantially in their EBNA2 and EBNA 3A/B/C latency proteins and have different phenotypes in B cells. T1 EBV transforms B cells more efficiently than T2 EBV in vitro, and T2 EBV-infected B cells are more lytic. We previously showed that both increased NFATc1/c2 activity, and an NFAT-binding motif within the BZLF1 immediate-early promoter variant (Zp-V3) contained in all T2 strains, contribute to lytic infection in T2 EBV-infected B cells. Here we compare cellular and viral gene expression in early-passage lymphoblastoid cell lines (LCLs) infected with either T1 or T2 EBV strains. Using bulk RNA-seq, we show that T2 LCLs are readily distinguishable from T1 LCLs, with approximately 600 differentially expressed cellular genes. Gene Set Enrichment Analysis (GSEA) suggests that T2 LCLs have increased B-cell receptor (BCR) signaling, NFAT activation, and enhanced expression of epithelial-mesenchymal-transition-associated genes. T2 LCLs also have decreased RNA and protein expression of a cellular gene required for survival of T1 LCLs, IRF4. In addition to its essential role in plasma cell differentiation, IRF4 decreases BCR signaling. Knock-down of IRF4 in a T1 LCL (infected with the Zp-V3-containing Akata strain) induced lytic reactivation whereas over-expression of IRF4 in Burkitt lymphoma cells inhibited both NFATc1 and NFATc2 expression and lytic EBV reactivation. Single-cell RNA-seq confirmed that T2 LCLs have many more lytic cells compared to T1 LCLs and showed that lytically infected cells have both increased NFATc1, and decreased IRF4, compared to latently infected cells. These studies reveal numerous differences in cellular gene expression in B cells infected with T1 versus T2 EBV and suggest that decreased IRF4 contributes to both the latent and lytic phenotypes in cells with T2 EBV.


Assuntos
Linfócitos B , Linfoma de Burkitt , Herpesvirus Humano 4 , Fatores Reguladores de Interferon , Linfócitos B/metabolismo , Linfócitos B/patologia , Linfócitos B/virologia , Linfoma de Burkitt/metabolismo , Linfoma de Burkitt/patologia , Linfoma de Burkitt/virologia , Herpesvirus Humano 4/metabolismo , Humanos , Fatores Reguladores de Interferon/metabolismo , Fenótipo , Proteínas Virais/metabolismo
9.
Front Cell Infect Microbiol ; 11: 784388, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34805002

RESUMO

Oral diseases are one of the most common pathologies affecting human health. These diseases are typically associated with dental plaque-biofilms, through either build-up of the biofilm or dysbiosis of the microbial community. Arginine can disrupt dental plaque-biofilms, and maintain plaque homeostasis, making it an ideal therapeutic to combat the development of oral disease. Despite our understanding of the actions of arginine towards dental plaque-biofilms, it is still unclear how or if arginine effects the mechanical integrity of the dental plaque-biofilm. Here we adapted a rotating-disc rheometry assay, a method used to quantify marine biofilm fouling, to study how arginine treatment of Streptococcus gordonii biofilms influences biofilm detachment from surfaces. We demonstrate that the assay is highly sensitive at quantifying the presence of biofilm and the detachment or rearrangement of the biofilm structure as a function of shear stress. We demonstrate that arginine treatment leads to earlier detachment of the biofilm, indicating that arginine treatment weakens the biofilm, making it more susceptible to removal by shear stresses. Finally, we demonstrate that the biofilm disrupting affect is specific to arginine, and not a general property of amino acids, as S. gordonii biofilms treated with either glycine or lysine had mechanical properties similar to untreated biofilms. Our results add to the understanding that arginine targets biofilms by multifaceted mechanisms, both metabolic and physical, further promoting the potential of arginine as an active compound in dentifrices to maintain oral health.


Assuntos
Microbiota , Streptococcus gordonii , Arginina , Biofilmes , Humanos
10.
mBio ; 12(4): e0227721, 2021 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-34465025

RESUMO

The species specificity of papillomaviruses has been a significant roadblock for performing in vivo pathogenesis studies in common model organisms. The Mus musculus papillomavirus type 1 (MmuPV1) causes cutaneous papillomas that can progress to squamous cell carcinomas in laboratory mice. The papillomavirus E6 and E7 genes encode proteins that establish and maintain a cellular milieu that allows for viral genome synthesis and viral progeny synthesis in growth-arrested, terminally differentiated keratinocytes. The E6 and E7 proteins provide this activity by binding to and functionally reprogramming key cellular regulatory proteins. The MmuPV1 E7 protein lacks the canonical LXCXE motif that mediates the binding of multiple viral oncoproteins to the cellular retinoblastoma tumor suppressor protein, RB1. Our proteomic experiments, however, revealed that MmuPV1 E7 still interacts with RB1. We show that MmuPV1 E7 interacts through its C terminus with the C-terminal domain of RB1. Binding of MmuPV1 E7 to RB1 did not cause significant activation of E2F-regulated cellular genes. MmuPV1 E7 expression was shown to be essential for papilloma formation. Experimental infection of mice with MmuPV1 expressing an E7 mutant that is defective for binding to RB1 caused delayed onset, lower incidence, and smaller sizes of papillomas. Our results demonstrate that the MmuPV1 E7 gene is essential and that targeting noncanonical activities of RB1, which are independent of RB1's ability to modulate the expression of E2F-regulated genes, contribute to papillomavirus-mediated pathogenesis. IMPORTANCE Papillomavirus infections cause a variety of epithelial hyperplastic lesions, or warts. While most warts are benign, some papillomaviruses cause lesions that can progress to squamous cell carcinomas, and approximately 5% of all human cancers are caused by human papillomavirus (HPV) infections. The papillomavirus E6 and E7 proteins are thought to function to reprogram host epithelial cells to enable viral genome replication in terminally differentiated, normally growth-arrested cells. E6 and E7 lack enzymatic activities and function by interacting and functionally altering host cell regulatory proteins. Many cellular proteins that can interact with E6 and E7 have been identified, but the biological relevance of these interactions for viral pathogenesis has not been determined. This is because papillomaviruses are species specific and do not infect heterologous hosts. Here, we use a recently established mouse papillomavirus (MmuPV1) model to investigate the role of the E7 protein in viral pathogenesis. We show that MmuPV1 E7 is necessary for papilloma formation. The retinoblastoma tumor suppressor protein (RB1) is targeted by many papillomaviral E7 proteins, including cancer-associated HPVs. We show that MmuPV1 E7 can bind RB1 and that infection with a mutant MmuPV1 virus that expresses an RB1 binding-defective E7 mutant caused smaller and fewer papillomas that arise with delayed kinetics.


Assuntos
Proteínas Oncogênicas Virais/metabolismo , Papillomaviridae/genética , Papillomaviridae/patogenicidade , Proteínas E7 de Papillomavirus/metabolismo , Proteínas de Ligação a Retinoblastoma/metabolismo , Fatores de Transcrição/metabolismo , Animais , Linhagem Celular Tumoral , Proteínas de Ligação a DNA/metabolismo , Humanos , Queratinócitos/virologia , Camundongos , Camundongos Nus , Proteínas Oncogênicas Virais/genética , Proteínas E7 de Papillomavirus/genética , Infecções por Papillomavirus/virologia , Ligação Proteica , Proteínas de Ligação a Retinoblastoma/genética
11.
J Oral Microbiol ; 13(1): 1910462, 2021 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-33968313

RESUMO

Background: Modulation of the commensal oral microbiota constitutes a promising preventive/therapeutic approach in oral healthcare. The use of prebiotics for maintaining/restoring the health-associated homeostasis of the oral microbiota has become an important research topic. Aims: This study hypothesised that in vitro 14-species oral biofilms can be modulated by (in)direct stimulation of beneficial/commensal bacteria with new potential prebiotic substrates tested at 1 M and 1%(w/v), resulting in more host-compatible biofilms with fewer pathogens, decreased virulence and less inflammatory potential. Methods: Established biofilms were repeatedly rinsed with N-acetyl-D-glucosamine, α-D-lactose, D-(+)-trehalose or D-(+)-raffinose at 1 M or 1%(w/v). Biofilm composition, metabolic profile, virulence and inflammatory potential were eventually determined. Results: Repeated rinsing caused a shift towards a more health-associated microbiological composition, an altered metabolic profile, often downregulated virulence gene expression and decreased the inflammatory potential on oral keratinocytes. At 1 M, the substrates had pronounced effects on all biofilm aspects, whereas at 1%(w/v) they had a pronounced effect on virulence gene expression and a limited effect on inflammatory potential. Conclusion: Overall, this study identified four new potential prebiotic substrates that exhibit different modulatory effects at two different concentrations that cause in vitro multi-species oral biofilms to become more host-compatible.

12.
J Clin Orthop Trauma ; 18: 209-215, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34026489

RESUMO

BACKGROUND & AIM: Utilization of augmented reality (AR) and heads-up displays (HUD) to aid orthopaedic surgery has the potential to benefit surgeons and patients alike through improved accuracy, safety, and educational benefits. With the COVID-19 pandemic, the opportunity for adoption of novel technology is more relevant. The aims are to assess the technology available, to understand the current evidence regarding the benefit and to consider challenges to implementation in clinical practice. METHODS & RESULTS: PRISMA guidelines were used to filter the literature. Of 1004 articles returned the following exclusion criteria were applied: 1) reviews/commentaries 2) unrelated to orthopaedic surgery 3) use of other AR wearables beyond visual aids leaving 42 papers for review.This review illustrates benefits including enhanced accuracy and reduced time of surgery, reduced radiation exposure and educational benefits. CONCLUSION: Whilst there are obstacles to overcome, there are already reports of technology being used. As with all novel technologies, a greater understanding of the learning curve is crucial, in addition to shielding our patients from this learning curve. Improvements in usability and implementing surgeons' specific needs should increase uptake.

13.
Arch Oral Biol ; 126: 105126, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33872861

RESUMO

OBJECTIVE: To investigate the effects of Dual Zinc plus Arginine formulations (aqueous solution and dentifrice) on tumor necrosis factor-alpha (TNF-α)-induced barrier dysfunction as well as on cell proliferation and migration in an in vitro gingival keratinocyte model. DESIGN: Gingival keratinocytes were seeded onto the membrane of a double-chamber system in the absence and presence of recombinant TNF-α and the formulations under investigation. The barrier function was assessed by determination of transepithelial electrical resistance (TER) and paracellular transport of fluorescein isothiocyanate (FITC)-dextran. The distribution of zonula occludens-1 (ZO-1) and occludin was visualized by immunofluorescence microscopy. The effects of the formulations on keratinocyte cell proliferation were determined using a fluorescent cell tracker dye, while a migration assay kit was used to investigate their effects on cell migration. RESULTS: Under conditions where TNF-α induces loss of keratinocyte barrier integrity, the Dual Zinc plus Arginine formulations (aqueous solution and dentifrice) protected the keratinocyte tight junction against the damages since they prevented the TNF-α-induced drop in TER and increase in FITC-dextran paracellular flux in the in vitro model. The treatment of keratinocytes with the formulations markedly mitigated the altered distribution of ZO-1 and occludin. Both formulations increased the proliferation of keratinocytes and alleviated the negative impact caused by TNF-α. Lastly, the formulations increased the migration capacity of keratinocytes. CONCLUSIONS: The ability of the Dual Zinc plus Arginine formulations to protect the barrier integrity of gingival keratinocytes from TNF-α-induced damage and to promote their proliferation and migration suggests that they may offer benefits for oral health.


Assuntos
Arginina , Fator de Necrose Tumoral alfa , Arginina/farmacologia , Proliferação de Células , Mucosa Intestinal , Queratinócitos , Zinco
15.
Bone Joint J ; 103-B(4): 755-761, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33789474

RESUMO

AIMS: This study sought to compare the rate of deep surgical site infection (SSI), as measured by the Centers for Disease Control and Prevention (CDC) definition, after surgery for a fracture of the hip between patients treated with standard dressings and those treated with incisional negative pressure wound therapy (iNPWT). Secondary objectives included determining the rate of recruitment and willingness to participate in the trial. METHODS: The study was a two-arm multicentre randomized controlled feasibility trial that was embedded in the World Hip Trauma Evaluation cohort study. Any patient aged > 65 years having surgery for hip fracture at five recruitment centres in the UK was considered to be eligible. They were randomly allocated to have either a standard dressing or iNPWT after closure of the wound. The primary outcome measure was deep SSI at 30 and 90 days, diagnosed according to the CDC criteria. Secondary outcomes were: rate of recruitment; further surgery within 120 days; health-related quality of life (HRQoL) using the EuroQol five-level five-dimension questionnaire (EQ-5D-5L); and related complications within 120 days as well as mobility and residential status at this time. RESULTS: A total of 462 valid randomizations were carried out (232 and 230 in the standard dressing and iNPWT groups, respectively). In the standard dressing group, 14 of 218 patients (6.4%) developed deep SSI. In the iNPWT group, four of 214 patients (1.9%) developed deep SSI. This gives a total rate of SSI of 4.2% (95% confidence interval (CI) 2.7% to 6.5%). Patients and surgeons were willing to participate in the study with 462 patients being recruited from a possible 749 (62.3%). CONCLUSION: The rate of deep SSI 30 days after surgery for a fracture of the hip was 4%, which makes a study comparing the clinical effectiveness of standard dressings and iNPWT feasible. Cite this article: Bone Joint J 2021;103-B(4):755-761.


Assuntos
Bandagens , Fraturas do Quadril/cirurgia , Tratamento de Ferimentos com Pressão Negativa , Infecção da Ferida Cirúrgica/prevenção & controle , Cicatrização , Idoso , Idoso de 80 Anos ou mais , Estudos de Viabilidade , Feminino , Humanos , Masculino , Reino Unido
16.
Bone Joint Res ; 9(9): 554-562, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32922764

RESUMO

AIMS: This study explores the reported rate of surgical site infection (SSI) after hip fracture surgery in published studies concerning patients treated in the UK. METHODS: Studies were included if they reported on SSI after any type of surgical treatment for hip fracture. Each study required a minimum of 30 days follow-up and 100 patients. Meta-analysis was undertaken using a random effects model. Heterogeneity was expressed using the I2 statistic. Risk of bias was assessed using a modified Newcastle-Ottawa Scale (NOS) system. RESULTS: There were 20 studies reporting data from 88,615 patients. Most were retrospective cohort studies from single centres. The pooled incidence was 2.1% (95% confidence interval (CI) 1.54% to 2.62%) across 'all types' of hip fracture surgery. When analyzed by operation type, the SSI incidences were: hemiarthroplasty 2.87% (95% CI 1.99% to 3.75%) and sliding hip screw 1.35% (95% CI 0.78% to 1.93%). There was considerable variation in definition of infection used, as well as considerable risk of bias, particularly as few studies actively screened participants for SSI. CONCLUSION: Synthesis of published estimates of infection yield a rate higher than that seen in national surveillance procedures. Biases noted in all studies would trend towards an underestimate, largely due to inadequate follow-up.

17.
J Oral Microbiol ; 12(1): 1798044, 2020 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-32944154

RESUMO

BACKGROUND AND OBJECTIVES: Porphyromonas gingivalis, a late colonizer of the periodontal biofilm, has been strongly associated with the chronic form of periodontitis. The aim of this study was to investigate the effects of a Dual Zinc plus Arginine formulation (aqueous solution and dentifrice) on the pathogenic properties of P. gingivalis and the barrier function of an in vitro gingival epithelium model. RESULTS: The Dual Zinc plus Arginine aqueous solution and dentifrice inhibited the hemolytic and proteolytic activities of P. gingivalis. The Dual Zinc plus Arginine aqueous solution and dentifrice enhanced the barrier function of an in vitro gingival epithelium model as determined by a time-dependent increase in transepithelial electrical resistance and decrease in paracellular permeability. This was associated with an increased immunolabeling of two important tight junction proteins: zonula occludens-1 and occludin. The deleterious effects of P. gingivalis on keratinocyte barrier function as well as the ability of the bacterium to translocate through a gingival epithelium model were attenuated in the presence of either Dual Zinc plus Arginine aqueous solution or dentifrice. CONCLUSIONS: The Dual Zinc plus Arginine formulation may offer benefits for patients affected by periodontal disease through its ability to attenuate the pathogenic properties of P. gingivalis and promote keratinocyte barrier function.

18.
Health Technol Assess ; 24(38): 1-86, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32821038

RESUMO

BACKGROUND: Major trauma is the leading cause of death in people aged < 45 years. Patients with major trauma usually have lower-limb fractures. Surgery to fix the fractures is complicated and the risk of infection may be as high as 27%. The type of dressing applied after surgery could potentially reduce the risk of infection. OBJECTIVES: To assess the deep surgical site infection rate, disability, quality of life, patient assessment of the surgical scar and resource use in patients with surgical incisions associated with fractures following major trauma to the lower limbs treated with incisional negative-pressure wound therapy versus standard dressings. DESIGN: A pragmatic, multicentre, randomised controlled trial. SETTING: Twenty-four specialist trauma hospitals representing the UK Major Trauma Network. PARTICIPANTS: A total of 1548 adult patients were randomised from September 2016 to April 2018. Exclusion criteria included presentation > 72 hours after injury and inability to complete questionnaires. INTERVENTIONS: Incisional negative-pressure wound therapy (n = 785), in which a non-adherent absorbent dressing covered with a semipermeable membrane is connected to a pump to create a partial vacuum over the wound, versus standard dressings not involving negative pressure (n = 763). Trial participants and the treating surgeon could not be blinded to treatment allocation. MAIN OUTCOME MEASURES: Deep surgical site infection at 30 days was the primary outcome measure. Secondary outcomes were deep infection at 90 days, the results of the Disability Rating Index, health-related quality of life, the results of the Patient and Observer Scar Assessment Scale and resource use collected at 3 and 6 months post surgery. RESULTS: A total of 98% of participants provided primary outcome data. There was no evidence of a difference in the rate of deep surgical site infection at 30 days. The infection rate was 6.7% (50/749) in the standard dressing group and 5.8% (45/770) in the incisional negative-pressure wound therapy group (intention-to-treat odds ratio 0.87; 95% confidence interval 0.57 to 1.33; p = 0.52). There was no difference in the deep surgical site infection rate at 90 days: 13.2% in the standard dressing group and 11.4% in the incisional negative-pressure wound therapy group (odds ratio 0.84, 95% confidence interval 0.59 to 1.19; p = 0.32). There was no difference between the two groups in disability, quality of life or scar appearance at 3 or 6 months. Incisional negative-pressure wound therapy did not reduce the cost of treatment and was associated with a low probability of cost-effectiveness. LIMITATIONS: Owing to the emergency nature of the surgery, we anticipated that some patients who were randomised would subsequently be unable or unwilling to participate. However, the majority of the patients (85%) agreed to participate. Therefore, participants were representative of the population with lower-limb fractures associated with major trauma. CONCLUSIONS: The findings of this study do not support the use of negative-pressure wound therapy in patients having surgery for major trauma to the lower limbs. FUTURE WORK: Our work suggests that the use of incisional negative-pressure wound therapy dressings in other at-risk surgical wounds requires further investigation. Future research may also investigate different approaches to reduce postoperative infections, for example the use of topical antibiotic preparations in surgical wounds and the role of orthopaedic implants with antimicrobial coatings when fixing the associated fracture. TRIAL REGISTRATION: Current Controlled Trials ISRCTN12702354 and UK Clinical Research Network Portfolio ID20416. FUNDING: This project was funded by the National Institute for Health Research Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 24, No. 38. See the NIHR Journals Library for further project information.


WHAT DID THE TRIAL FIND?: We found no evidence of a difference in the rate of surgical site infection between those patients randomised to negative-pressure wound therapy and those patients randomised to standard wound dressings. There was no difference in the rate of other wound healing complications or in the patients' self-report of disability, health-related quality of life or scar healing. Negative-pressure wound therapy is very unlikely to be cost-effective for the NHS. In conclusion, and contrary to previous reports, the findings of this study do not support the use of negative-pressure wound therapy in patients having surgery for major trauma to their legs.


Major trauma is the leading cause of death worldwide in people aged < 45 years and a significant cause of short- and long-term health problems. In 85% of major trauma patients, the injury involves broken bones. Surgery to fix broken bones in the lower limbs is complicated and has risks, one of the main ones being wound infection. In these patients, rates of wound infection have been reported to be as high as 27%. One factor that may affect the risk of infection is the type of dressing applied after surgery. In this trial, we compared standard wound dressings with a new treatment called incisional negative-pressure wound therapy. Negative-pressure wound therapy is a special type of dressing whereby gentle suction is applied to the surface of the wound. A total of 1548 patients from 24 specialist trauma hospitals in the UK agreed to take part and were assigned at random to receive either a standard wound dressing or negative-pressure wound therapy after their surgery. We reviewed the recovery of the patients for 6 months. We recorded how many had an infection in the surgical wound and asked the patients to rate the extent of their disability, their quality of life and the scar healing. We also collected information about the cost of treatment.


Assuntos
Bandagens , Fraturas Expostas/cirurgia , Tratamento de Ferimentos com Pressão Negativa , Infecção da Ferida Cirúrgica , Cicatrização/fisiologia , Adulto , Bandagens/economia , Bandagens/estatística & dados numéricos , Feminino , Humanos , Extremidade Inferior/lesões , Masculino , Pessoa de Meia-Idade , Tratamento de Ferimentos com Pressão Negativa/economia , Tratamento de Ferimentos com Pressão Negativa/estatística & dados numéricos , Infecção da Ferida Cirúrgica/epidemiologia , Infecção da Ferida Cirúrgica/prevenção & controle , Reino Unido/epidemiologia
19.
PLoS Pathog ; 16(6): e1008590, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32542010

RESUMO

EBV transforms B cells in vitro and causes human B-cell lymphomas including classical Hodgkin lymphoma (CHL), Burkitt lymphoma (BL) and diffuse large B-cell lymphoma (DLBCL). The EBV latency protein, EBNA2, transcriptionally activates the promoters of all latent viral protein-coding genes expressed in type III EBV latency and is essential for EBV's ability to transform B cells in vitro. However, EBNA2 is not expressed in EBV-infected CHLs and BLs in humans. EBV-positive CHLs have type II latency and are largely driven by the EBV LMP1/LMP2A proteins, while EBV-positive BLs, which usually have type I latency are largely driven by c-Myc translocations, and only express the EBNA1 protein and viral non-coding RNAs. Approximately 15% of human BLs contain naturally occurring EBNA2-deleted viruses that support a form of viral latency known as Wp-restricted (expressing the EBNA-LP, EBNA3A/3B/3C, EBNA1 and BHRF1 proteins), but whether Wp-restricted latency and/or EBNA2-deleted EBV can induce lymphomas in humanized mice, or in the absence of c-Myc translocations, is unknown. Here we show that a naturally occurring EBNA2-deleted EBV strain (P3HR1) isolated from a human BL induces EBV-positive B-cell lymphomas in a subset of infected cord blood-humanized (CBH) mice. Furthermore, we find that P3HR1-infected lymphoma cells support two different viral latency types and phenotypes that are mutually exclusive: 1) Large (often multinucleated), CD30-positive, CD45-negative cells reminiscent of the Reed-Sternberg (RS) cells in CHL that express high levels of LMP1 but not EBNA-LP (consistent with type II viral latency); and 2) smaller monomorphic CD30-negative DLBCL-like cells that express EBNA-LP and EBNA3A but not LMP1 (consistent with Wp-restricted latency). These results reveal that EBNA2 is not absolutely required for EBV to form tumors in CBH mice and suggest that P3HR1 virus can be used to model EBV positive lymphomas with both Wp-restricted and type II latency in vivo.


Assuntos
Infecções por Vírus Epstein-Barr , Antígenos Nucleares do Vírus Epstein-Barr/genética , Deleção de Genes , Herpesvirus Humano 4/fisiologia , Doença de Hodgkin , Linfoma Difuso de Grandes Células B , Proteínas Virais/genética , Latência Viral , Animais , Linhagem Celular , Infecções por Vírus Epstein-Barr/genética , Infecções por Vírus Epstein-Barr/metabolismo , Infecções por Vírus Epstein-Barr/patologia , Infecções por Vírus Epstein-Barr/virologia , Antígenos Nucleares do Vírus Epstein-Barr/metabolismo , Herpesvirus Humano 4/patogenicidade , Doença de Hodgkin/genética , Doença de Hodgkin/metabolismo , Doença de Hodgkin/patologia , Doença de Hodgkin/virologia , Humanos , Linfoma Difuso de Grandes Células B/genética , Linfoma Difuso de Grandes Células B/metabolismo , Linfoma Difuso de Grandes Células B/patologia , Linfoma Difuso de Grandes Células B/virologia , Camundongos , Proteínas Virais/metabolismo
20.
J Virol ; 94(10)2020 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-32132242

RESUMO

Epstein-Barr virus (EBV) causes B cell lymphomas and transforms B cells in vitro The EBV protein EBNA3A collaborates with EBNA3C to repress p16 expression and is required for efficient transformation in vitro An EBNA3A deletion mutant EBV strain was recently reported to establish latency in humanized mice but not cause tumors. Here, we compare the phenotypes of an EBNA3A mutant EBV (Δ3A) and wild-type (WT) EBV in a cord blood-humanized (CBH) mouse model. The hypomorphic Δ3A mutant, in which a stop codon is inserted downstream from the first ATG and the open reading frame is disrupted by a 1-bp insertion, expresses very small amounts of EBNA3A using an alternative ATG at residue 15. Δ3A caused B cell lymphomas at rates similar to their induction by WT EBV but with delayed onset. Δ3A and WT tumors expressed equivalent levels of EBNA2 and p16, but Δ3A tumors in some cases had reduced LMP1. Like the WT EBV tumors, Δ3A lymphomas were oligoclonal/monoclonal, with typically one dominant IGHV gene being expressed. Transcriptome sequencing (RNA-seq) analysis revealed small but consistent gene expression differences involving multiple cellular genes in the WT EBV- versus Δ3A-infected tumors and increased expression of genes associated with T cells, suggesting increased T cell infiltration of tumors. Consistent with an impact of EBNA3A on immune function, we found that the expression of CLEC2D, a receptor that has previously been shown to influence responses of T and NK cells, was markedly diminished in cells infected with EBNA3A mutant virus. Together, these studies suggest that EBNA3A contributes to efficient EBV-induced lymphomagenesis in CBH mice.IMPORTANCE The EBV protein EBNA3A is expressed in latently infected B cells and is important for efficient EBV-induced transformation of B cells in vitro In this study, we used a cord blood-humanized mouse model to compare the phenotypes of an EBNA3A hypomorph mutant virus (Δ3A) and wild-type EBV. The Δ3A virus caused lymphomas with delayed onset compared to the onset of those caused by WT EBV, although the tumors occurred at a similar rate. The WT EBV and EBNA3A mutant tumors expressed similar levels of the EBV protein EBNA2 and cellular protein p16, but in some cases, Δ3A tumors had less LMP1. Our analysis suggested that Δ3A-infected tumors have elevated T cell infiltrates and decreased expression of the CLEC2D receptor, which may point to potential novel roles of EBNA3A in T cell and NK cell responses to EBV-infected tumors.


Assuntos
Infecções por Vírus Epstein-Barr/virologia , Antígenos Nucleares do Vírus Epstein-Barr/genética , Antígenos Nucleares do Vírus Epstein-Barr/metabolismo , Sangue Fetal/metabolismo , Herpesvirus Humano 4/genética , Linfoma/virologia , Animais , Linfócitos B/virologia , Transformação Celular Viral , Modelos Animais de Doenças , Regulação Neoplásica da Expressão Gênica , Células HEK293 , Herpesvirus Humano 4/fisiologia , Humanos , Células Matadoras Naturais/imunologia , Linfoma/genética , Linfoma/patologia , Linfoma de Células B , Camundongos , Mutagênese Sítio-Dirigida , Análise de Sequência de RNA , Deleção de Sequência , Linfócitos T/imunologia , Proteínas Virais/genética , Proteínas Virais/metabolismo , Latência Viral/genética
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