10 research outputs found
Early Healing Events around Titanium Implant Devices with Different Surface Microtopography: A Pilot Study in an In Vivo Rabbit Model
In the present pilot study, the authors morphologically investigated sandblasted, acid-etched surfaces (SLA) at very early experimental times. The tested devices were titanium plate-like implants with flattened wide lateral sides and jagged narrow sides. Because of these implant shape and placement site, the device gained a firm mechanical stability but the largest portion of the implant surface lacked direct contact with host bone and faced a wide peri-implant space rich in marrow tissue, intentionally created in order to study the interfacial interaction between metal surface and biological microenvironment. The insertion of titanium devices into the proximal tibia elicited a sequence of healing events. Newly formed bone proceeded through an early distance osteogenesis, common to both surfaces, and a delayed contact osteogenesis which seemed to follow different patterns at the two surfaces. In fact, SLA devices showed a more osteoconductive behavior retaining a less dense blood clot, which might be earlier and more easily replaced, and leading to a surface-conditioning layer which promotes osteogenic cell differentiation and appositional new bone deposition at the titanium surface. This model system is expected to provide a starting point for further investigations which clarify the early cellular and biomolecular events occurring at the metal surface
Prevalence of p53 dysregulations in feline oral squamous cell carcinoma and non-neoplastic oral mucosa
Squamous cell carcinoma is the most common malignant oral tumor in cats. The late presentation is one of the factors contributing to the detrimental prognosis of this disease. The immunohistochemical expression of the p53 tumor suppressor protein has been reported in 24% to 65% of feline oral squamous cell carcinomas, but no study has systematically evaluated in this tumor the presence of p53 encoding gene (TP53) mutations. The aim of this retrospective study was to determine whether p53 immunohistochemistry accurately reflects the mutational status of the TP53 gene in feline oral squamous cell carcinoma. Additionally, the prevalence of p53 dysregulation in feline oral squamous cell carcinoma was compared with that of feline non-neoplastic oral mucosa, in order to investigate the relevance of these dysregulations in cancer development. The association between p53 dysregulations and exposure to environmental tobacco smoke and tumor characteristics was further assessed. Twenty-six incisional biopsies of oral squamous cell carcinomas and 10 cases each of lingual eosinophilic granuloma, chronic gingivostomatitis and normal oral mucosa were included in the study. Eighteen squamous cell carcinomas (69%) expressed p53 and 18 had mutations in exons 5\u20138 of TP53. The agreement between immunohistochemistry and mutation analysis was 77%. None of non-neoplastic oral mucosa samples had a positive immunohistochemical staining, while one case each of eosinophilic granuloma and chronic gingivostomatitis harbored TP53 mutations. Unlike previously hypothesized, p53 dysregulations were not associated with exposure to environmental tobacco smoke. These results suggest an important role of p53 in feline oral tumorigenesis. Additionally, the immunohistochemical detection of p53 expression appears to reflect the presence of TP53 mutations in the majority of cases. It remains to be determined if the screening for p53 dysregulations, alone or in association with other markers, can eventually contribute to the early detection of this devastating disease
Safety and efficacy of the ChAdOx1 nCoV-19 vaccine (AZD1222) against SARS-CoV-2: an interim analysis of four randomised controlled trials in Brazil, South Africa, and the UK.
BACKGROUND: A safe and efficacious vaccine against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), if deployed with high coverage, could contribute to the control of the COVID-19 pandemic. We evaluated the safety and efficacy of the ChAdOx1 nCoV-19 vaccine in a pooled interim analysis of four trials. METHODS: This analysis includes data from four ongoing blinded, randomised, controlled trials done across the UK, Brazil, and South Africa. Participants aged 18 years and older were randomly assigned (1:1) to ChAdOx1 nCoV-19 vaccine or control (meningococcal group A, C, W, and Y conjugate vaccine or saline). Participants in the ChAdOx1 nCoV-19 group received two doses containing 5 × 1010 viral particles (standard dose; SD/SD cohort); a subset in the UK trial received a half dose as their first dose (low dose) and a standard dose as their second dose (LD/SD cohort). The primary efficacy analysis included symptomatic COVID-19 in seronegative participants with a nucleic acid amplification test-positive swab more than 14 days after a second dose of vaccine. Participants were analysed according to treatment received, with data cutoff on Nov 4, 2020. Vaccine efficacy was calculated as 1 - relative risk derived from a robust Poisson regression model adjusted for age. Studies are registered at ISRCTN89951424 and ClinicalTrials.gov, NCT04324606, NCT04400838, and NCT04444674. FINDINGS: Between April 23 and Nov 4, 2020, 23 848 participants were enrolled and 11 636 participants (7548 in the UK, 4088 in Brazil) were included in the interim primary efficacy analysis. In participants who received two standard doses, vaccine efficacy was 62·1% (95% CI 41·0-75·7; 27 [0·6%] of 4440 in the ChAdOx1 nCoV-19 group vs71 [1·6%] of 4455 in the control group) and in participants who received a low dose followed by a standard dose, efficacy was 90·0% (67·4-97·0; three [0·2%] of 1367 vs 30 [2·2%] of 1374; pinteraction=0·010). Overall vaccine efficacy across both groups was 70·4% (95·8% CI 54·8-80·6; 30 [0·5%] of 5807 vs 101 [1·7%] of 5829). From 21 days after the first dose, there were ten cases hospitalised for COVID-19, all in the control arm; two were classified as severe COVID-19, including one death. There were 74 341 person-months of safety follow-up (median 3·4 months, IQR 1·3-4·8): 175 severe adverse events occurred in 168 participants, 84 events in the ChAdOx1 nCoV-19 group and 91 in the control group. Three events were classified as possibly related to a vaccine: one in the ChAdOx1 nCoV-19 group, one in the control group, and one in a participant who remains masked to group allocation. INTERPRETATION: ChAdOx1 nCoV-19 has an acceptable safety profile and has been found to be efficacious against symptomatic COVID-19 in this interim analysis of ongoing clinical trials. FUNDING: UK Research and Innovation, National Institutes for Health Research (NIHR), Coalition for Epidemic Preparedness Innovations, Bill & Melinda Gates Foundation, Lemann Foundation, Rede D'Or, Brava and Telles Foundation, NIHR Oxford Biomedical Research Centre, Thames Valley and South Midland's NIHR Clinical Research Network, and AstraZeneca
Safety and efficacy of the ChAdOx1 nCoV-19 vaccine (AZD1222) against SARS-CoV-2: an interim analysis of four randomised controlled trials in Brazil, South Africa, and the UK
Background
A safe and efficacious vaccine against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), if deployed with high coverage, could contribute to the control of the COVID-19 pandemic. We evaluated the safety and efficacy of the ChAdOx1 nCoV-19 vaccine in a pooled interim analysis of four trials.
Methods
This analysis includes data from four ongoing blinded, randomised, controlled trials done across the UK, Brazil, and South Africa. Participants aged 18 years and older were randomly assigned (1:1) to ChAdOx1 nCoV-19 vaccine or control (meningococcal group A, C, W, and Y conjugate vaccine or saline). Participants in the ChAdOx1 nCoV-19 group received two doses containing 5 × 1010 viral particles (standard dose; SD/SD cohort); a subset in the UK trial received a half dose as their first dose (low dose) and a standard dose as their second dose (LD/SD cohort). The primary efficacy analysis included symptomatic COVID-19 in seronegative participants with a nucleic acid amplification test-positive swab more than 14 days after a second dose of vaccine. Participants were analysed according to treatment received, with data cutoff on Nov 4, 2020. Vaccine efficacy was calculated as 1 - relative risk derived from a robust Poisson regression model adjusted for age. Studies are registered at ISRCTN89951424 and ClinicalTrials.gov, NCT04324606, NCT04400838, and NCT04444674.
Findings
Between April 23 and Nov 4, 2020, 23 848 participants were enrolled and 11 636 participants (7548 in the UK, 4088 in Brazil) were included in the interim primary efficacy analysis. In participants who received two standard doses, vaccine efficacy was 62·1% (95% CI 41·0–75·7; 27 [0·6%] of 4440 in the ChAdOx1 nCoV-19 group vs71 [1·6%] of 4455 in the control group) and in participants who received a low dose followed by a standard dose, efficacy was 90·0% (67·4–97·0; three [0·2%] of 1367 vs 30 [2·2%] of 1374; pinteraction=0·010). Overall vaccine efficacy across both groups was 70·4% (95·8% CI 54·8–80·6; 30 [0·5%] of 5807 vs 101 [1·7%] of 5829). From 21 days after the first dose, there were ten cases hospitalised for COVID-19, all in the control arm; two were classified as severe COVID-19, including one death. There were 74 341 person-months of safety follow-up (median 3·4 months, IQR 1·3–4·8): 175 severe adverse events occurred in 168 participants, 84 events in the ChAdOx1 nCoV-19 group and 91 in the control group. Three events were classified as possibly related to a vaccine: one in the ChAdOx1 nCoV-19 group, one in the control group, and one in a participant who remains masked to group allocation.
Interpretation
ChAdOx1 nCoV-19 has an acceptable safety profile and has been found to be efficacious against symptomatic COVID-19 in this interim analysis of ongoing clinical trials
Unerupted teeth in dogs and cats: a clinical, radiographic and histological study in 64 cases (2001-2017)
DETERMINAZIONE DELLA PRESSIONE INTRAOCULARE NEL CANE, MEDIANTE TONOPEN XL, PER LA VALUTAZIONE DI PROTOCOLLI ANESTESIOLOGICI IDONEI IN CHIRURGIA OFTALMICA.
Lo scopo del lavoro è quello di determinare l'effetto sulla pressione intraoculare prodotto dai diversi agenti anestetici impiegati durante la chirurgia oftalmica nel cane. La regolazione della pressione intraoculare può essere influenzata dal protocollo anestesiologico ed è importante per il successo della chirurgia oftalmica. 49 cani sono stati divisi random in 4 gruppi trattati con 4 diversi protocolli anestesiologici. E' stata misurata la pressione intraoculare mediante Tonopen XL prima e dopo la somministrazione dei farmaci anestetici. I dati sono stati analizzati utilizzando una statistica descrittiva, test parametrici ed analisi della varianza. Non ci sono state importanti variazioni della pressione intraoculare correlate al tipo di protocollo anestesiologico utilizzato. In conclusione i risultati ottenuti dimostrano che i protocolli anestesiologici utilizzati risultano essere sicuri ed appropriati per la chirurgia oftalmica
Environmental risk factors for the development of oral squamous cell carcinoma in cats
Abstract Background Risk factors for oral squamous cell carcinoma (OSCC) in cats are derived from a single study dated almost 20 years ago. The relationship between inflammation of oral tissues and OSCC is still unclear. Objectives To investigate previously proposed and novel potential risk factors for OSCC development, including oral inflammatory diseases. Animals Hundred cats with OSCC, 70 cats with chronic gingivostomatitis (CGS), 63 cats with periodontal disease (PD), and 500 controls. Methods Prospective, observational case‐control study. Cats with OSCC were compared with an age‐matched control sample of client‐owned cats and cats with CGS or PD. Owners of cats completed an anonymous questionnaire including demographic, environmental and lifestyle information. Results On multivariable logistic regression, covariates significantly associated with an increased risk of OSCC were rural environment (OR: 1.77; 95% CI: 1.03‐3.04; P = .04), outdoor access (OR: 1.68; 95% CI: 1.07‐2.63; P = .02), environmental tobacco smoke (OR: 1.77; 95% CI: 1.05‐3; P = .03), and petfood containing chemical additives (OR: 1.98; 95% CI: 1.04‐3.76; P = .04). Risk factors shared with CGS and PD were outdoor access and petfood containing chemical additives, respectively. A history of oral inflammation was reported in 35% of cats with OSCC but did not emerge as a risk factor. Conclusions and Clinical Importance The study proposes novel potential risk factors for OSCC in cats. Although a history of inflammatory oral disease was not significantly more frequent compared with random age‐matched controls, OSCC shared several risk factors with CGS and PD