Pietro Ghezzi | Università di Urbino "Carlo Bo" (original) (raw)

Papers by Pietro Ghezzi

Free Radical Biology and Medicine, 2021

Many studies reported that redox enzymes, particularly thioredoxin and peroxiredoxin, can be rele... more Many studies reported that redox enzymes, particularly thioredoxin and peroxiredoxin, can be released by cells and act as soluble mediators in immunity. Recently, it became clear that peroxiredoxins can be secreted via the exosome-release route, yet it remains unclear how this exactly happens and why. This review will first introduce briefly the possible redox states of protein cysteines and the role of redox enzymes in their regulation. We will then discuss the studies on the extracellular forms of some of these enzymes, their association with exosomes/extracellular vesicles and with exosome micro-RNAs (miRNAs)/mRNAs involved in oxidative processes, relevant in infection and inflammation.

Environment International, 2022

Background Oxidative stress is conjectured to be related to many diseases. Furthermore, it is hyp... more Background
Oxidative stress is conjectured to be related to many diseases. Furthermore, it is hypothesized that radiofrequency fields may induce oxidative stress in various cell types and thereby compromise human and animal health. This systematic review (SR) aims to summarize and evaluate the literature related to this hypothesis.

Objectives
The main objective of this SR is to evaluate the associations between the exposure to radiofrequency electromagnetic fields and oxidative stress in experimental models (in vivo and in vitro).

Methods
The SR framework has been developed following the guidelines established in the WHO Handbook for Guideline Development and the Handbook for Conducting a Literature-Based Health Assessment). We will include controlled in vivo and in vitro laboratory studies that assess the effects of an exposure to RF-EMF on valid markers for oxidative stress compared to no or sham exposure. The protocol is registered in PROSPERO.

We will search the following databases: PubMed, Embase, Web of Science Core Collection, Scopus, and the EMF-Portal. The reference lists of included studies and retrieved review articles will also be manually searched.

Study appraisal and synthesis method
Data will be extracted according to a pre-defined set of forms developed in the DistillerSR online software and synthesized in a meta-analysis when studies are judged sufficiently similar to be combined. If a meta-analysis is not possible, we will describe the effects of the exposure in a narrative way.

Risk of bias
The risk of bias will be assessed with the NTP/OHAT risk of bias rating tool for human and animal studies.

We will use GRADE to assess the certainty of the conclusions (high, moderate, low, or inadequate) regarding the association between radiofrequency electromagnetic fields and oxidative stress.

Funding
This work was funded by the World Health Organization (WHO).

Registration
The protocol was registered on the PROSPERO webpage on July 8, 2021.

Antioxidants, 2022

Long-term ingestion of arsenicals, a heterogeneous group of toxic compounds, has been associated ... more Long-term ingestion of arsenicals, a heterogeneous group of toxic compounds, has been associated with a wide spectrum of human pathologies, which include various malignancies. Although their mechanism of toxicity remains largely unknown, it is generally believed that arsenicals mainly produce their effects via direct binding to protein thiols and ROS formation in different subcellular compartments. The generality of these mechanisms most probably accounts for the different effects mediated by different forms of the metalloid in a variety of cells and tissues. In order to learn more about the molecular mechanisms of cyto- and genotoxicity, there is a need to focus on specific arsenic compounds under tightly controlled conditions. This review focuses on the mechanisms regulating the mitochondrial formation of ROS after exposure to low concentrations of a specific arsenic compound, NaAsO2, and their crosstalk with the nuclear factor (erythroid-2 related) factor 2 antioxidant signaling and the endoplasmic reticulum stress response.

Journal of Cannabis Research, 2022

Background There is a growing literature on the potential medical uses of Cannabis sativa and can... more Background
There is a growing literature on the potential medical uses of Cannabis sativa and cannabinoid compounds. Although these have only been approved by regulatory agencies for a few indications, there is a hype about their possible benefits in a variety of conditions and a large market in the wellness industry. As in many cases patients search for information on cannabis products online, we have analyzed the information on medical cannabis available on the Internet. Therefore, this study aims at assessing the quality of the information available online on medical cannabis.

Methods
We searched “medical cannabis” on June 2019 using google.com and downloaded the first 243 websites. After excluding dead links or websites with no information about cannabis, 176 websites were included. They were then classified for their typology (e.g., commercial, government, news outlets). As an indicator of trustworthiness, we used the Journal of American Medical Association (JAMA) score, which assesses the indication of date, author, ownership of the website, and the presence of references. We also considered if a website is certified by Health-On-the-Net (HON), an independent organization, by displaying a HONCode symbol. Subsequently, we performed a content analysis to assess both the medical cannabis indications mentioned by webpages and the completeness of the information provided (whether they mentioned potential side effects and legal/regulatory issues or not).

Results
Analyzing 176 webpages returned by a search engine, we found that 52% of them were news websites. Pain, epilepsy, and multiple sclerosis were the most frequently mentioned therapeutic areas (cited in 92, 84 and 80 webpages, respectively), which did not always match those for which there is regulatory approval. Information was also incomplete, with only 22% of the webpages mentioning potential side effects. Health portal websites provided the most complete information, with all of them (n = 7) reporting side effects. On average, 80% of webpages had a neutral stance on the potential benefits of medical cannabis, with commercial websites having more frequently a positive stance (67%).

Conclusions
We conclude that the information that can be found online is not always aligned in terms of the therapeutic areas for which science-based evidence is often still weak.

Biomark Insights. , 2022

Objective: There is an association between frailty and arterial stiffness. However, arterial stif... more Objective:
There is an association between frailty and arterial stiffness. However, arterial stiffness does not uniformly correlate with the spectrum of frailty states. Both oxidative stress and inflammaging contribute to vascular ageing. There are no human studies exploring links between arterial stiffness, oxidative stress, inflammaging and frailty. Our objective is to investigate arterial stiffness and inflammaging as predictors of frailty states.

Methods:
An observational longitudinal cohort study will be used to examine the association between arterial stiffness, oxidative stress and inflammation in 50 older adults (⩾70 years) with clinical frailty scores (CFS) ⩽6 over 6 months. All study measurements will be taken at baseline. Frailty assessment will include hand-grip strength, timed-up and go test, mini-mental state examination, geriatric depression scale and sarcopenia using body composition measurements with Tanita®. Arterial stiffness measurements will include carotid-femoral pulse wave velocity (cfPWV) and carotid-radial pulse wave velocity (crPWV) using Complior (Alam Medical, France). CAVI device will measure Cardio-ankle vascular index and ankle brachial index (ABI). Oxidative stress blood markers nitrotyrosine (NT) and 8-hydroxy-2’-deoxyguanosin (8-oxo-dG) and inflammation markers high-sensitive C-reactive protein (hs-CRP) and interlukin-6(IL-6) will be measured at baseline and 6 month along with lipid profile and glycated haemoglobin.

Results (data analysis plan):
Descriptive statistics for continuous data using means and standard deviations for normality distributed variables or medians and inter-quartile ranges for skewed variables will be used. Participants will be categorised into CFS 1-3, and CFS 4-6. Categorical data will use frequencies and comparison between groups. Change in frailty between the groups over 6 months will be compared using paired t-test. Simple linear regression will be done between frailty measures, arterial stiffness, inflammation and oxidative stress biomarkers. Significance will be at P < .05.

Conclusion:
This study data will inform a larger, multi-centre study exploring further the interplay between frailty, biomarkers and arterial stiffness parameters.

FASEB Journal, 2023

Several redox modifications have been described during viral infection, including influenza virus... more Several redox modifications have been described during viral infection, including influenza virus infection, but little is known about glutathionylation and this respiratory virus. Glutathionylation is a reversible, post-translational modifica-tion, in which protein cysteine forms transient disulfides with glutathione (GSH), catalyzed by cellular oxidoreductases and in particular by glutaredoxin (Grx). We show here that (i) influenza virus infection induces protein glutathionylation, including that of viral proteins such as hemagglutinin (HA);(ii) Grx1-mediated deglutathionylation is important for the viral life cycle, as its inhibition, either with an inhibitor of its enzymatic activity or by siRNA, decreases viral replication. Overall these data contribute to the characterization of the complex picture of redox regulation of the influenza virus replication cycle and could help to identify new targets to control respiratory viral infection.

SocArXiv, 2023

Background. Measures against the COVID-19 pandemics have been subject of political polarization a... more Background. Measures against the COVID-19 pandemics have been subject of political polarization also in the United Kingdom. While this has been studied in the broader context of misinformation, the debate around non-pharmacological interventions (NPI) , the and the political implications of different views of their risks and benefits, has not been taken into account with sufficient depth
Research question. Our research question was: Are politically-oriented UK newspapers more likely to promote a more, or less, precautionary views toward the use of NPIs?
Methods. We used the Mediacloud database to search the names of scientists with different precautionary views (i.e.: signatories of the Great Barrington Declaration and of the John Snow Memorandum) and analyze the frequency with which they are mentioned in newspapers with different political orientation.
Results. Scientists with more precautionary positions are more likely to be mentioned in left-leaning newspapers, whereas those with less precautionary views on right-leaning ones. The two groups segregated also in terms of co-authorship of academic papers.
Conclusions. Scientists with different opinions in relation to NPIs are mentioned by UK newspapers in a way that is dependent on the political orientation of the newspaper.

Frontiers in Medicine, 2020

Probiotics are over-the-counter products marketed for enhancing human health. Online information ... more Probiotics are over-the-counter products marketed for enhancing human health. Online information has been key in promoting probiotics worldwide. However, only few rigorous clinical studies have met the stringent criteria required to establish the efficacy and safety of probiotics. The present study was undertaken to assess the information quality of webpages referring to probiotics and to compare the recommendations available online with the information collected from trusted scientific sources. We evaluated 150 webpages returned by Google searching “probiotics” in terms of typology of website, health information quality based on the JAMA score and the HONcode certification, as well as completeness of the information based on the presence of four criteria: (1) links to scientific references supporting health claims, (2) cautionary notes about level of evidence for alleged benefits, (3) safety considerations, and (4) regulatory status. We then enumerated the health claims mentioned online and the corresponding clinical trials and reviews registered in the Cochrane library. Finally, the conclusions of Cochrane reviews were used to assess the level of scientific evidence of the information available through Google search. HON-certified websites were significantly more frequent in the top 10 websites than in the remaining websites. In terms of completeness of information, only 10% of webpages met all four criteria, 40% had a cautionary note on benefits, 35% referred to scientific literature, and only 25% mentioned potential side effects. The results of the content analysis led us to conclude that: (1) the most frequent typologies of webpages returned by Google are commercial and news, (2) commercial websites on average provide the least reliable information, and (3) significant numbers of claimed benefits of probiotics are not supported by scientific evidence. This study highlights important biases in the probiotics information available online, underlining the need to improve the quality and objectivity of information provided to the public.

arXiv:1912.00898, 2019

The fact that Internet companies may record our personal data and track our online behaviour for ... more The fact that Internet companies may record our personal data and track our online behaviour for commercial or political purpose has emphasized aspects related to online privacy. This has also led to the development of search engines that promise no tracking and privacy. Search engines also have a major role in spreading low-quality health information such as that of anti-vaccine websites. This study investigates the relationship between search engines’ approach to privacy and the scientific quality of the information they return. We analyzed the first 30 webpages returned searching “vaccines autism” in English, Spanish, Italian and French. The results show that “alternative” search engines (Duckduckgo, Ecosia, Qwant, Swisscows and Mojeek) may return more anti-vaccine pages (10-53%) than Google.com (0%). Some localized versions of Google, however, returned more anti-vaccine webpages (up to 10%) than Google.com. Our study suggests that designing a search engine that is privacy savvy and avoids issues with filter bubbles that can result from user-tracking is necessary but insufficient; instead mechanisms should be developed to test search engines from the perspective of information quality (particularly for health-related webpages), before they can be deemed trustworthy providers of public health information.

Free Radical Research, 2019

Peroxiredoxin 1 (PRDX1) is an antioxidant enzyme that, when secreted, can act as a proinflammator... more Peroxiredoxin 1 (PRDX1) is an antioxidant enzyme that, when secreted, can act as a proinflammatory signal. Here we studied the regulation of intracellular PRDX1 by lipopolysaccharide (LPS) and interferon-gamma (IFNγ) in the RAW 264.7 mouse macrophage cell line. While LPS or IFNγ alone did not affect PRDX1 protein levels, their combination led to an almost complete loss of the PRDX1 dimer. This was likely mediated by the increased production of nitric oxide (NO) as it was reversed by the NO synthase inhibitor ʟ N-methylarginine (ʟ NMMA), while a NO-releasing agent decreased PRDX1 levels. Inhibition of the proteasome with MG132 also prevented the loss of the PRDX1 dimer, suggesting that the decrease is due to a NO-activated proteasomal degradation pathway.
By contrast with the decrease in protein levels, LPS increased PRDX1 mRNA and this effect was amplified by IFNγ. Two other Nrf2 target genes, thioredoxin reductase (TXNRD1) and heme oxygenase (HMOX1), were also induced by LPS but IFNγ did not increase their expression further. This study shows that inflammation differentially regulates PRDX1 at the levels of protein stability and gene expression, and that NO plays a key role in this mechanism.

Frontiers in Medicine, 2019

Background: The concept that one can “boost” immunity is a popular one. Although the only evidenc... more Background: The concept that one can “boost” immunity is a popular one. Although the only evidence-based approach to this is vaccination, the lay public is exposed to a wide range of information on how to boost immunity. The aim of this study was to analyze such information available on the Internet.

Methods and findings: We visited 185 webpages returned from a Google search on “boost immunity” and classified them by typology (blogs, commercial, government, no-profit, news, professional, scientific journals) and by using standard indicators of health information quality (JAMA score, HONCode). We then analyzed their content in terms of disease and “boosters” mentioned. Commercial and news websites represented one third of the results each. Of the 37 approaches to boost immunity recorded, the top ones were diet (77% of webpages), fruit (69%), vitamins (67%), antioxidants (52%), probiotics (51%), minerals (50%), and vitamin C (49%). Interestingly, vaccines ranked 27th, with only 12% of webpages mentioning them.

Conclusions: Commercial websites are an important component of the information available to the public on the topic, and thus contribute providing biased information.

Free Radic Biol Med, 2019

Inflammation is associated with production of reactive oxygen species (ROS) and results in the in... more Inflammation is associated with production of reactive oxygen species (ROS) and results in the induction of thioredoxin (TXN) and peroxiredoxins (PRDXs) and activation of nuclear factor-like 2 (Nrf2). In this study we have used the mouse RAW 264.7 macrophage and the human THP-1 monocyte cell line to investigate the pattern of expression of three Nrf2 target genes, PRDX1, TXN reductase (TXNRD1) and heme oxygenase (HMOX1), by activation of different Toll-like receptors (TLRs). We found that, while the TLR4 agonist lipopolysaccharide (LPS) induces all three genes, the pattern of induction with agonists for TLR1/2, TLR3, TLR2/6 and TLR7/8 differs depending on the gene and the cell line. In all cases, the extent of induction was HMOX1>TXNRD1>PRDX1. Since LPS was a good inducer of all genes in both cell lines, we studied the mechanisms mediating LPS induction of the three genes using mouse RAW 264.7 cells. To assess the role of ROS we used the antioxidant N-acetylcysteine (NAC). Only LPS induction of HMOX1 was inhibited by NAC while that of TXNRD1 and PRDX1 was unaffected. These three genes were also induced by phorbol myristate acetate (PMA), a ROS-inducer acting by activation of protein kinase C (PKC). The protein kinase inhibitor staurosporine inhibited the induction of all three genes by PMA but only that of HMOX1 by LPS. This indicates that activation of these genes by inflammatory agents is regulated by different mechanisms involving either ROS or protein kinases, or both.

Front Immunol., 2019

Secretion of IL-1β From Monocytes in Gout Is Redox Independent. Alberts BM1, Bruce C1, Basnayake ... more Secretion of IL-1β From Monocytes in Gout Is Redox Independent.
Alberts BM1, Bruce C1, Basnayake K2, Ghezzi P1, Davies KA1, Mullen LM1.
Author information
Abstract
The pro-inflammatory cytokine interleukin-1β (IL-1β) plays important roles in immunity but is also implicated in autoimmune disease. The most well-established mechanism of IL-1β secretion is via activation of the NOD-like receptor family pyrin domain containing-3 (NLRP3) inflammasome which requires an initial priming signal followed by an activating signal. However, the precise mechanism by which the inflammasome is activated remains unclear. The role of reactive oxygen species (ROS) in this process is contradictory, with some studies suggesting that ROS are crucial while others describe opposite effects. In this study, we evaluated the effects of oxidative stress on IL-1β secretion. Gout is a disease driven solely by IL-1β secretion in response to monosodium urate (MSU) crystals which form during periods of hyperuricemia and thus presents an opportunity to study factors contributing to IL-1β secretion. Sera and monocytes were isolated from patients with gout to determine whether differences in antioxidant status could explain the susceptibility of these individuals to gout attacks. In addition, sera and monocytes were collected from patients with chronic kidney disease (CKD) for comparison as this condition is associated with high levels of oxidative stress and disturbances in serum uric acid levels. There were differences in some aspects of antioxidant defenses in gout patients and these were mainly due to higher serum uric acid. Monocytes from gout patients were more responsive to priming, but not activation, of the NLRP3 inflammasome. However, expression of the components of the NLRP3 inflammasome were unaffected by priming or activation of the inflammasome, nor were these expression levels differentially regulated in gout patients. Inhibition of ROS by N-Acetyl Cysteine inhibited TLR2-induced priming of the NLRP3 inflammasome, but had no effect on MSU-induced activation. Together these findings demonstrate that oxidative stress only affects priming of the NLRP3 inflammasome but does not influence activation.

Front Med (Lausanne), 2018

What Is Health Information Quality? Ethical Dimension and Perception by Users. Al-Jefri M1, Evans... more What Is Health Information Quality? Ethical Dimension and Perception by Users.
Al-Jefri M1, Evans R1, Uchyigit G1, Ghezzi P2.
Author information
Abstract
Introduction: The popularity of seeking health information online makes information quality (IQ) a public health issue. The present study aims at building a theoretical framework of health information quality (HIQ) that can be applied to websites and defines which IQ criteria are important for a website to be trustworthy and meet users' expectations. Methods: We have identified a list of HIQ criteria from existing tools and assessment criteria and elaborated them into a questionnaire that was promoted via social media and mainly the University. Responses (329) were used to rank the different criteria for their importance in trusting a website and to identify patterns of criteria using hierarchical cluster analysis. Results: HIQ criteria were organized in five dimensions based on previous theoretical frameworks as well as on how they cluster together in the questionnaire response. We could identify a top-ranking dimension (scientific completeness) that describes what the user is expecting to know from the websites (in particular: description of symptoms, treatments, side effects). Cluster analysis also identified a number of criteria borrowed from existing tools for assessing HIQ that could be subsumed to a broad "ethical" dimension (such as conflict of interests, privacy, advertising policies) that were, in general, ranked of low importance by the participants. Subgroup analysis revealed significant differences in the importance assigned to the various criteria based on gender, language and whether or not of biomedical educational background. Conclusions: We identified criteria of HIQ and organized them in dimensions. We observed that ethical criteria, while regarded highly in the academic and medical environment, are not considered highly by the public.

Rheumatol Int., 2019

Accuracy, completeness and accessibility of online information on fibromyalgia. Basavakumar D1, F... more Accuracy, completeness and accessibility of online information on fibromyalgia.
Basavakumar D1, Flegg M2, Eccles J1, Ghezzi P3.
Author information
Abstract
Fibromyalgia is a multi-factorial illness primarily characterised by widespread chronic pain and fatigue, with several symptoms and associated conditions. Due to a lack of clinical awareness and an absence of objective diagnostic measures, fibromyalgia patients often engage with online health information. The aim is to investigate the completeness and trustworthiness of the information available online on fibromyalgia. Google.co.uk was searched for 'fibromyalgia', the first 200 webpages were imported and 148 were analysed for standard health information quality criteria (JAMA score, HONcode) as well as completeness of information in terms of symptoms, causes and treatments mentioned. The most frequent typology of webpages was from health professionals (38%), with commercial websites being less frequent (7%). Overall, the quality, completeness and accessibility of online health information was poor. Completeness of coverage for symptoms, causes and associated conditions was especially lacking, with pages from not-for-profit organisations discussing the highest number of symptoms (median 8, min 0, max 11, interquartile range, IQR 4.5; n = 14) compared to the rest of the websites in the search engine results (median 4, min 0, max 11, IQR 4; n = 134). Mean readability was grade 9 (median 9, min 1, max 18, IQR 3), with only 8% websites meeting the recommended readability of grade 6. The Internet provides incomplete information on fibromyalgia, which does not fulfil the most queried aspect(s) by patients, symptoms, and may be difficult to understand by lay persons. Not-for-profit organisations provide the most complete information compared to other types of websites.

J Rheumatol, 2019

Precipitation of Soluble Uric Acid Is Necessary for In Vitro Activation of the NLRP3 Inflammasome... more Precipitation of Soluble Uric Acid Is Necessary for In Vitro Activation of the NLRP3 Inflammasome in Primary Human Monocytes.
Alberts BM1, Barber JS1, Sacre SM1, Davies KA1, Ghezzi P1, Mullen LM1.
Author information
Abstract
OBJECTIVE:
To investigate the effects of soluble uric acid (UA) on expression and activation of the NOD-like receptor (NLR) pyrin domain containing protein 3 (NLRP3) inflammasome in human monocytes to elucidate the role of hyperuricemia in the pathogenesis of gout.

METHODS:
Primary human monocytes and the THP-1 human monocyte cell line were used to determine the effects of short- and longterm exposure to UA on activation of the NLRP3 inflammasome and subsequent interleukin 1β (IL-1β) secretion by ELISA and cell-based assays. Expression of key NLRP3 components in monocytes from patients with a history of gout were analyzed by quantitative PCR.

RESULTS:
Precipitation of UA was required for activation of the NLRP3 inflammasome and subsequent release of IL-1β in human monocytes. Neither monosodium urate (MSU) crystals nor soluble UA had any effect on activation of the transcription factor, nuclear factor-κB. Prolonged exposure of monocytes to soluble UA did not alter these responses. However, both MSU crystals and soluble UA did result in a 2-fold increase in reactive oxygen species. Patients with gout (n = 15) had significantly elevated serum UA concentrations compared to healthy individuals (n = 16), yet secretion of IL-1β and expression of NLRP3 inflammasome components in monocytes isolated from these patients were not different from those of healthy controls.

CONCLUSION:
Despite reports indicating that soluble UA can prime and activate the NLRP3 inflammasome in human peripheral blood mononuclear cells, precipitation of soluble UA into MSU crystals is essential for in vitro NLRP3 signaling in primary human monocytes.

Frontiers in Immunology, 2018

The 1998 Lancet paper by Wakefield et al., despite subsequent retraction and evidence indicating ... more The 1998 Lancet paper by Wakefield et al., despite subsequent retraction and evidence indicating no causal link between vaccinations and autism, triggered significant parental concern. The aim of this study was to analyze the online information available on this topic. Using localized versions of Google, we searched “autism vaccine” in English, French, Italian, Portuguese, Mandarin, and Arabic and analyzed 200 websites for each search engine result page (SERP). A common feature was the newsworthiness of the topic, with news outlets representing 25–50% of the SERP, followed by unaffiliated websites (blogs, social media) that represented 27–41% and included most of the vaccine-negative websites. Between 12 and 24% of websites had a negative stance on vaccines, while most websites were pro-vaccine (43–70%). However, their ranking by Google varied. While in Google.com, the first vaccine-negative website was the 43rd in the SERP, there was one vaccine-negative webpage in the top 10 websites in both the British and Australian localized versions and in French and two in Italian, Portuguese, and Mandarin, suggesting that the information quality algorithm used by Google may work better in English. Many webpages mentioned celebrities in the context of the link between vaccines and autism, with Donald Trump most frequently. Few websites (1–5%) promoted complementary and alternative medicine (CAM) but 50–100% of these were also vaccine-negative suggesting that CAM users are more exposed to vaccine-negative information. This analysis highlights the need for monitoring the web for information impacting on vaccine uptake.

Background: Endothelial injury is an early and enduring feature of cardiovascular disease. Inflam... more Background: Endothelial injury is an early and enduring feature of cardiovascular disease. Inflammation and hypoxia may be responsible for this, and are often associated with the up-regulation of several transcriptional factors that include Hypoxia Inducible Factor-1 (HIF-1). Although it has been reported that HIF-1α is detectable in plasma, it is known to be unstable. Our aim was to optimize an assay for HIF-1α to be applied to in vitro and in vivo applications, and to use this assay to assess the release kinetics of HIF-1 following endothelial injury.
Methods: An ELISA for the measurement of HIF in cell-culture medium and plasma was optimized, and the assay used to determine the best conditions for sample collection and storage. The results of the ELISA were validated using Western blotting and immunohistochemistry (IHC). In vitro, a standardized injury was produced in a monolayer of rat aortic endothelial cells (RAECs) and intracellular HIF-1α was measured at intervals over 24 hours. In vivo, a rat angioplasty model was used. The right carotid artery was injured using a 2F Fogarty balloon catheter. HIF-1α was measured in the plasma and in the arterial tissue (0, 1, 2, 3 and 5 days post injury).
Results: The HIF-1α ELISA had a limit of detection of 2.7 pg/ mL and was linear up to 1000 pg/ mL. Between and within-assay coefficient of variation values were less than 15%. HIF-1α was unstable in cell lysates and plasma, and it was necessary to add a protease inhibitor immediately after collection, and to store samples at -800C prior to analysis. The dynamics of HIF-1α release were different for the in vitro and in vivo models. In vitro, HIF-1α reached maximum concentrations approximately 2h post injury, whereas peak values in plasma and tissues occurred approximately 2 days post injury, in the balloon injury model.
Conclusion: HIF-1α can be measured in plasma, but this requires careful sample collection and storage. The carotid artery balloon injury model is associated with the transient release of HIF-1α into the circulation that probably reflects the hypoxia induced in the artery wall.

Biomarkers are widely used not only as prognostic or diagnostic indicators, or as surrogate marke... more Biomarkers are widely used not only as prognostic or diagnostic indicators, or as surrogate markers of disease in clinical trials, but also to formulate theories of pathogenesis. We identify two problems in the use of biomarkers in mechanistic studies. The first problem arises in the case of multifactorial diseases, where different combinations of multiple causes result in patient heterogeneity. The second problem arises when a pathogenic mediator is difficult to measure. This is the case of the oxidative stress (OS) theory of disease, where the causal components are reactive oxygen species (ROS) that have very short half-lives. In this case, it is usual to measure the traces left by the reaction of ROS with biological molecules, rather than the ROS themselves. Borrowing from the philosophical theories of signs, we look at the different facets of biomarkers and discuss their different value and meaning in multifactorial diseases and system medicine to inform their use in patient stratification in personalized medicine.

The Breast, 2017

Offering breast cancer patients treatment choice has become a priority as the involvement of pati... more Offering breast cancer patients treatment choice has become a priority as the involvement of patients in the decision-making process is associated with improved physical and psychological outcomes. As the Internet is increasingly being used by patients as a source of medical information, it is important to evaluate the quality of information relating to breast cancer on the Internet. We analysed 200 websites returned by google.co.uk searching “breast cancer treatment options” in terms of their typology and treatment options described. These were related to standard measures of health information quality such as the JAMA score and the presence of quality certifications, as well as readability.

We found that health portals were of higher quality whilst commercial and professional websites were of poorer quality in terms of JAMA criteria. Overall, readability was higher than previously reported for other conditions, and Google ranked websites with better readability higher. Most websites discussed surgical and medical treatments. Few websites, with a large proportion being of commercial typology, discussed complementary and alternative medicine. Google ranked professional websites low whilst websites from non-profit organizations were promoted in the ranking.