A Delphi approach to establishing consensus on best practice for the diagnosis and treatment of Demodex blepharitis.

Demodex blepharitis does not have agreed standardized guidelines. The aim of this study was to classify signs and symptoms and to develop appropriate management strategies for Demodex blepharitis from a consensus of expert advice. METHODS: A total of 11 anterior segment experts (ophthalmologists, optometrists and a contact lens optician) working in the United Kingdom participated in a modified 2-round Delphi panel. A mixed-methods approach was adopted and a survey questionnaire for round 1 was formulated, constructed from information in the available literature. Based on panel responses from round 1, feedback was provided and a round 2 questionnaire was formulated. More than two-thirds majority (72%) was used for consensus building. RESULTS: Based on the clinical presentation of signs and symptoms along with associated conditions and risk factors, a diagnostic algorithm was proposed for the clinical investigation of Demodex blepharitis. A treatment algorithm was also proposed with first-line and second-line treatment recommendations for Demodex blepharitis. CONCLUSION: The recommendation from this study provides the first effort in formulating clinical diagnostic algorithm and management guidelines for Demodex blepharitis. The guidelines include appropriate magnification on the slit lamp, associated signs, symptoms, risk factors and suggested management options. These guidelines can be used in a routine eyecare setting to encourage eyecare practitioners in tailoring the investigation and management of Demodex blepharitis.

Tear Fluid Biomarkers and Quality of Life in People with Type 2 Diabetes and Dry Eye Disease.

Dry eye disease (DED) can be extremely distressing and is common in type 2 diabetes (T2D). To investigate potential biomarkers of DED in T2D, panels of proteins in tears, alongside clinical signs and symptoms of DED, were assessed. Patients were classified into four groups: T2D + DED (n = 47), T2D-only (n = 41), DED-only (n = 17) and healthy controls (n = 17). All patients underwent the Ocular Surface Disease Index (OSDI) and Dry Eye-Related Quality of Life (DEQS) questionnaires, tear evaporation rate (TER), fluorescein tear break-up time (fTBUT), corneal fluorescein staining (CFS) and Schirmer 1 test assessments. Six metabolic proteins and 14 inflammatory cytokines were analyzed with multiplex bead analysis. Interleukin (IL)-6 and IL-8 concentrations in tears were significantly higher in the T2D + DED group, and these biomarkers were positively correlated with CFS. In addition, tear IL-6 was negatively correlated with fTBUT in the T2D + DED group. Clinical signs of DED in the T2D + DED group were similar to the DED-only group. The T2D + DED group had more patients with moderate and severe DED (versus the DED-only group), suggesting a different pathogenesis for DED in T2D versus DED-only. Therefore, IL-6 and IL-8 could potentially be diagnostic biomarkers of DED in T2D.

Demodex Blepharitis: A Survey-Based Approach to Investigate Knowledge, Attitudes, and Practices Among Optometrists in India.

Purpose: To investigate the knowledge, attitudes, and practice towards Demodex blepharitis among optometrists in India. Methods: The study was conducted in the form of an online survey using Research Electronic Data Capture (REDCap). The survey link was distributed via direct e-mail and social media platforms, and it was comprised of 20 questions divided into two sections. The first section focused on the practitioners' demographics and their views on the general health of the eyelid. The second section of the survey was specific and aimed at obtaining information on identifying and treating Demodex blepharitis, and was only completed by those respondents who looked for Demodex mites. Results: The survey was completed by 174 optometrists. The prevalence of blepharitis in the general population was judged by the respondents to be 40%, whereas the prevalence of Demodex mites was estimated to be 29%. Interestingly, the prevalence of Demodex mites in people with blepharitis was estimated to be 30%. This estimated prevalence was substantially lower than that reported in the literature on the subject. 66% of participants believed Demodex mites to be a significant cause of ocular discomfort, whereas only 30% of participants would intervene to diagnose and manage Demodex blepharitis in their patients. Optometrists differed in their preferred method of diagnosis and management of Demodex infestation in eyelids. Conclusion: The result of this survey suggests that Demodex blepharitis is a highly under-diagnosed condition in India, with nearly 30% of surveyed optometrists managing this condition. The study also observed a lack of awareness and consensus among surveyed optometrists with regards to diagnosis and appropriate treatment methods to control Demodex infestation in eyelids.

Prevalence and Characteristics of HIV-Associated Stroke in a Tertiary Hospital Setting in South Africa.

BACKGROUND AND OBJECTIVES: Antiretroviral treatment (ART) era HIV-associated stroke data from sub-Saharan Africa are limited. We determined the prevalence of HIV in patients presenting with acute symptomatic stroke and compared risk factors, clinical characteristics, and brain imaging with age-matched stroke patients without HIV. METHODS: We conducted a retrospective study of adults presenting with any type of stroke to Tygerberg Hospital in a 12-month period. Patients living with HIV (PLWH) and HIV-uninfected (HIV-) patients were matched based on age group (1:2 ratio). Patients were identified by keyword search, while HIV status was ascertained from laboratory data. Clinical and imaging data were extracted from medical records. RESULTS: Among 884 patients presenting with acute strokes, the minimum prevalence of HIV infection was 9.3% (95% CI: 7.4%-11.2%), with 496 patients (56.1%) with negative HIV status and 306 patients with unknown HIV status (34.6%). The mean age at presentation in PLWH was 46 (±11) years compared with 55 (±14) years in HIV- patients (p < 0.001). Smoking was less prevalent in PLWH with an adjusted relative risk ratio of RR = 0.58 (95% CI: 0.39-0.86). Concurrent infection was more prevalent in PLWH (25.6% vs 4.9%, p ≤ 0.001) with an adjusted relative risk ratio of RR = 2.07 (95% CI: 1.49-2.84), largely in patients with a CD4 count <200 cells/µL. PLWH with higher CD4 counts (≥200 cells/µL, 51.3%) had more traditional risk factors and less concurrent infection. Among PLWH, 68.3% were on ART, and 39.3% of them had been started or restarted on ART within the past 6 months. Basal ganglia infarcts (35.6% vs 18.3%, p = 0.014) and multiple vascular territory involvement (25.4% vs 7.7%, p = 0.002) were more common in PLWH. Clinical presentation, ischemic stroke type, and in-hospital outcomes did not differ between the groups. DISCUSSION: Stroke patients with HIV were younger, had less traditional cardiovascular risk factors, and more concurrent infections than patients without HIV, especially those with a lower CD4 count. Recent ART initiation or reinitiation rates were high. Significant differences in CT brain imaging findings were seen. Understanding the multifactorial mechanisms underlying increased stroke risk, including associated infections and potential ART-associated immune reconstitution, is crucial and needs further study.

After-hour trauma-radiograph interpretation in the emergency centre of a District Hospital.

Introduction: Plain radiographs remain a first-line trauma investigation. Most trauma radiographs worldwide are reported by junior doctors. This study assesses the accuracy of after-hour acute trauma radiograph reporting by emergency centre (EC) doctors in an African district hospital. Methods: An institutional review board approved retrospective descriptive study over two consecutive weekends in February 2020. The radiologist report on the admission radiographs of adult trauma patients was compared with the initial EC interpretation. The accuracy, sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) for EC interpretation were calculated with 95% confidence intervals (95%CI). The association between reporting accuracy and anatomical region, mechanism of injury, time of investigation, and the number of abnormalities per radiograph was assessed. Results: 140 radiographs were included, of which 49 (35%) were abnormal. EC doctors recorded (95%CI) 77% (69-84%) accuracy, 38% (25-54%) sensitivity, 97% (91-99%) specificity, 86% (65-95%) PPV and 76% (71-80%) NPV. Performance was associated with the anatomical region (p=0.02), mechanism of injury (p=<0.01) time of day (p=0.04) and the number of abnormalities on the film (p=<0.01). The highest sensitivity was achieved in reports of the appendicular skeleton (42%) and in the setting of simple blunt trauma (62%). Overall accuracy was in line with the range (44%-99%) reported in the international literature. Discussion: Accurate reporting of acute trauma radiographs is challenging. Key factors impact performance. Further training of junior doctors in this area of clinical practice is recommended. Future work should focus on assessing the impact of such training on reporting performance.

Diurnal variation on tear stability and correlation with tear cytokine concentration.

PURPOSE: To investigate the effect of time of day on tear evaporation rate (TER) and tear break-up time, and its possible relationship with the concentration of inflammatory tear molecules (cytokines) in healthy subjects. METHODS: Participants with healthy ocular surfaces attended 3 visits, including the screening visit (V0), the 2nd visit (V1) and the 3rd visit (V2). There were 7-day intervals between visits. Participants with Dry Eye Disease (DED) were excluded by using appropriate clinical tests during V0. Clinical evaluation (TER and Non-Invasive Tear Break-Up Time (NITBUT)) and tear collection were performed during V1 and V2, between 9 and 10AM and 3-4PM. The relative humidity and temperature of the examination room were also measured. The tear fluid concentrations of 15 cytokines were measured by multiplex bead analysis. RESULTS: Seven men and 10 women (mean age ± S.D; 25.1 ± 6.63 years old) participated in the study. There were no differences in neither the TER and NITBUT outcomes, nor humidity and temperature among times or visits. Eleven out of the 15 cytokines measured were detectable in tear fluids in > 50% of the participants. In the tear levels, no significant (p > 0.05) inter- and/or intra-day differences were detected for EGF, fractalkine, IL-1RA, IL-1ß and IP-10. However, significant inter-day differences were found in the tear levels of IL-10 (p = 0.027), IFN-γ (p = 0.035) and TNF-α(p = 0.04) and intra-day differences in the tear levels of IL-8/CXCL8 (p = 0.034) and MCP-1 (p = 0.002). A significant correlation between TER and IL1-ß, IL-2, and Fractalkine (p = 0.03, p = 0.03 and p = 0.046, respectively) was found at V1. CONCLUSIONS: NITBUT and TER values had no significant variability over the course of a day (AM versus PM), or on different days in healthy participants when humidity and temperature were constant. However, some tear molecule levels did show inter- and intra-day variability, having an inconsistent and moderate correlation with TER diurnal variation.

Strip meniscometry tube: a rapid method for assessing aqueous deficient dry eye.

BACKGROUND: The aim of this study was to investigate the utility of strip meniscometry tube (SMTube) for the quantitative assessment of the tear film, by comparing it to measurements of tear turnover rate using the gold standard method, fluorophotometry. Also, to determine the viability of this test as a diagnostic tool for aqueous deficient dry eye (ADDE), to inform appropriate clinical management. METHODS: Thirty-two participants (15 ADDE; 17 non-ADDE) were recruited. Tear turnover rate of the right eye of each subject was conducted with an automated scanning fluorophotometer and SMTube test was conducted. Tear meniscus height was assessed using a slitlamp biomicroscope and eyepiece graticule. RESULTS: Significant differences between the ADDE and the non-ADDE groups were found for all measures: tear turnover rate 7.9 ± 1.8 versus 19.6 ± 5.9 per cent/minute (p < 0.001), SMTube 3.2 ± 1.1 versus 5.7 ± 2.3 mm (p = 0.001) and tear meniscus height 0.18 ± 0.05 versus 0.23 ± 0.04 mm (p = 0.004). Moreover, significant correlations were found between tear turnover rate and SMTube (rho = 0.78, p < 0.001), tear turnover rate and tear meniscus height (rho = 0.54, p < 0.001) and SMTube and tear meniscus height (rho = 0.47, p < 0.01). Using a receiver operating characteristic curve, SMTube showed a sensitivity of 67 per cent and a specificity of 88 per cent for the diagnosis of ADDE. CONCLUSION: Given its performance, availability, speed and the fact it is relatively cheap, the study shows that the SMTube can be used as an alternative to fluorophotometry to assess tear production. It appears from the results that SMTube is a viable minimally invasive test for the diagnosis of ADDE.

Anti-tumor Activity of the Type I PRMT Inhibitor, GSK3368715, Synergizes with PRMT5 Inhibition through MTAP Loss.

Type I protein arginine methyltransferases (PRMTs) catalyze asymmetric dimethylation of arginines on proteins. Type I PRMTs and their substrates have been implicated in human cancers, suggesting inhibition of type I PRMTs may offer a therapeutic approach for oncology. The current report describes GSK3368715 (EPZ019997), a potent, reversible type I PRMT inhibitor with anti-tumor effects in human cancer models. Inhibition of PRMT5, the predominant type II PRMT, produces synergistic cancer cell growth inhibition when combined with GSK3368715. Interestingly, deletion of the methylthioadenosine phosphorylase gene (MTAP) results in accumulation of the metabolite 2-methylthioadenosine, an endogenous inhibitor of PRMT5, and correlates with sensitivity to GSK3368715 in cell lines. These data provide rationale to explore MTAP status as a biomarker strategy for patient selection.

Patient-reported severity of dry eye and quality of life in diabetes.

PURPOSE: The purpose of the study was to assess the relationship between patient-reported severity of dry eye disease (DED), quality of life (QoL), presence of diabetic retinopathy (DR) and length of disease duration in people with type 1 diabetes mellitus (DM1) and type 2 diabetes mellitus (DM2). PATIENTS AND METHODS: A survey of 152 people (110 with and 42 without diabetes). All participants completed the Ocular Surface Disease Index (OSDI) and Dry Eye-related Quality of Life Score (DEQS) questionnaires. RESULTS: Forty-four percent of all diabetic subjects reported dry eye symptoms, compared to 29% in the control group. Patients with DM2 reported dry eye symptoms more frequently than those with DM1 (55% and 27% respectively, P=0.001). Dry eye severity was linked to a significant deterioration in QoL in both types of diabetes (DM1, r=0.609 and P=0.036; DM2, r=0.417 and P=0.011). Irrespective of DR, the presence of DED was significantly higher in DM2 compared to DM1 (with DR, P=0.011; without DR, P=0.018). CONCLUSION: Dry eye symptoms are associated with reduced QoL and are more common in people with DM2 than in DM1, irrespective of DR status. Routine clinical screening for severe DED could potentially allow for a timely and more effective treatment and could contribute to mitigating the dry eye-associated reduction in QoL in those with DM2.

The Role of the Integrated Digital Radiology System in Assessing the Impact of Patient Load on Emergency Computed Tomography (CT) Efficiency.

Time-critical management is of particular significance in the trauma and emergency setting, where intervals from patient arrival to diagnostic imaging and from imaging to radiology report are key determinants of outcome. This study, based in the Trauma and Emergency Unit of a large, tertiary-level African hospital with a fully digital radiology department, assessed the impact of increased workload on computerised tomography (CT) efficiency. Sequential, customised searches of the institutional radiology information system (RIS) were conducted to define two weekends in 2016 with the lowest and highest emergency CT workloads, respectively. The electronic RIS timestamps defining the intervals between key steps in the CT workflow were extracted and analysed for each weekend. With the exception of radiologist reporting time, workflow steps were significantly prolonged by increased workload. This study highlights the potential role of the integrated digital radiology system in enabling a detailed analysis of imaging workflow, thereby facilitating the identification and appropriate management of bottlenecks.

Narrow Spectrum Kinase Inhibitors Demonstrate Promise for the Treatment of Dry Eye Disease and Other Ocular Inflammatory Disorders.

Purpose: The purpose of this study is to determine the potential of narrow spectrum kinase inhibitors (NSKIs) to treat inflammatory eye disorders. Methods: Human conjunctival epithelial (HCE) cells were retrieved from subjects via impression cytology. Real-time quantitative PCR (qPCR) was performed on HCE cells to determine gene expression of NSKI kinase targets and proinflammatory cytokines in dry eye disease (DED) patients versus healthy controls. qPCR also assessed p38α expression in hyperosmolar-treated Chang conjunctival epithelial cells. Interaction of NSKI TOP1362 with the kinases was evaluated in ATP-dependent Z-LYTE and competition binding assays. Anti-inflammatory activity was assessed in human peripheral blood mononuclear cells and primary macrophages. In an endotoxin-induced uveitis (EIU) study, lipopolysaccharide (LPS) was administered intravitreally to Lewis rats. TOP1362, dexamethasone, or vehicle was administered topically, and inflammatory cytokine levels were measured 6 hours after LPS injection. Results: HCE cells from DED patients showed significantly increased expression of p38α, spleen tyrosine kinase (Syk), Src, lymphocyte-specific protein tyrosine kinase (Lck), interleukin one beta (IL-1ß), interleukin eight (IL-8), monocyte chemotactic protein-1 (MCP-1), and matrix metalloproteinase-9 (MMP-9). TOP1362 strongly inhibited the kinase targets p38α, Syk, Src, and Lck, blocked the rise in p38α expression in hyperosmolar Chang cells, and potently reduced inflammatory cytokine release in cellular models of innate and adaptive immunities. In the EIU model, TOP1362 dose-dependently attenuated the LPS-induced rise in inflammatory cell infiltration and ocular cytokine levels with efficacy comparable to that of dexamethasone. Conclusions: TOP1362 is a potent inhibitor of kinases upregulated in DED and markedly attenuates proinflammatory cytokine release in vitro and in vivo, highlighting the therapeutic potential of NSKIs for treating ocular inflammation, such as that observed in DED.

Effect of tear supplements on signs, symptoms and inflammatory markers in dry eye.

PURPOSE: Three tear supplements were compared for their effects on the signs, symptoms and inflammatory status of subjects with dry eye disease. Assessments were made before and after both 2 and 4 weeks of treatment. METHODS: In this masked, randomized, 3-way crossover trial, eighteen dry eye subjects were recruited. At each visit, symptoms, tear evaporation rate, stability and osmolarity were measured and tear samples were analyzed for 7 inflammatory markers, using multiplex immunoassays. The 3 treatments included carboxymethylcellulose-glycerine-castor oil (CGC), carboxymethylcellulose (CMC) and hydroxypropyl guar (HPG). The CGC and HPG drops are emulsified lipids; CGC also contains osmoprotectants. The CMC drop is a standard aqueous polymeric supplement. RESULTS: Significant improvements were seen in symptoms (OSDI) and tear stability (NITBUT) with all 3 treatments at 4 weeks. At 4 weeks post-CGC, 6 out of 7 biomarkers demonstrated a >25% reduction (in 40% of subjects). The same reduction (>25%) was seen in 10% of the subjects for CMC and in none of the subjects for HPG. No significantly different change to either evaporation rate or tear osmolarity was found following any of the three treatments. CONCLUSIONS: In this study, the CGC treatment resulted in the greatest reduction in ocular biomarkers of inflammation, while all 3 treatments reduced symptoms and improved tear stability. These results indicate that subject-perceived symptomatic improvements are not necessarily associated with a reduction in objective measures of inflammation.

Biomarkers of ocular surface disease using impression cytology.

Impression cytology (IC) is a technique which permits the retrieval of the outermost layer of ocular surface cells via the use of various types of filters. It is a minimally invasive method of evaluating human conjunctival epithelial cell morphology in the diagnosis of dry eye disease, a common and distressing disorder associated with ageing, contact lens wear, autoimmune disorders and refractive (LASIK) surgery. IC may also be utilized in the diagnosis of other ocular diseases, such as keratoconus and thyroid orbitopathy. More recently, IC has been utilized for the subsequent investigation of gene and protein expression of conjunctival cells in order to identify novel diagnostic biomarkers and to further our understanding of the mechanisms underlying ocular surface disease. This review will therefore examine the literature concerning the role of IC in identifying cellular markers of eye disease, systemic diseases with ocular involvement and potential novel therapeutic targets.

Tear fluid biomarkers in ocular and systemic disease: potential use for predictive, preventive and personalised medicine.

In the field of predictive, preventive and personalised medicine, researchers are keen to identify novel and reliable ways to predict and diagnose disease, as well as to monitor patient response to therapeutic agents. In the last decade alone, the sensitivity of profiling technologies has undergone huge improvements in detection sensitivity, thus allowing quantification of minute samples, for example body fluids that were previously difficult to assay. As a consequence, there has been a huge increase in tear fluid investigation, predominantly in the field of ocular surface disease. As tears are a more accessible and less complex body fluid (than serum or plasma) and sampling is much less invasive, research is starting to focus on how disease processes affect the proteomic, lipidomic and metabolomic composition of the tear film. By determining compositional changes to tear profiles, crucial pathways in disease progression may be identified, allowing for more predictive and personalised therapy of the individual. This article will provide an overview of the various putative tear fluid biomarkers that have been identified to date, ranging from ocular surface disease and retinopathies to cancer and multiple sclerosis. Putative tear fluid biomarkers of ocular disorders, as well as the more recent field of systemic disease biomarkers, will be shown.

Poly Ethoxy Ethyl Glycinamide (PEE-G) Dendrimers: Dendrimers Specifically Designed for Pharmaceutical Applications.

Poly ethoxy ethyl glycinamide (PEE-G) dendrimers have been specifically designed and synthesized with the aim of providing a readily available dendrimer scaffold that can be used to make products that can meet the stringent requirements of pharmaceutical applications. The synthesis has been refined to produce dendrimers that are of high HPLC purity. The suitability of PEE-G dendrimers for their designed use has been verified by subsequent measurements to demonstrate that they are of high stability, high aqueous solubility, low cytotoxicity, low immunogenicity and with low in vivo toxicity in an escalating-dose rat study. PEE-G dendrimers therefore provide a useful scaffold for researchers wanting to develop dendrimer-based drug candidates.

EPMA position paper in cancer: current overview and future perspectives.

At present, a radical shift in cancer treatment is occurring in terms of predictive, preventive, and personalized medicine (PPPM). Individual patients will participate in more aspects of their healthcare. During the development of PPPM, many rapid, specific, and sensitive new methods for earlier detection of cancer will result in more efficient management of the patient and hence a better quality of life. Coordination of the various activities among different healthcare professionals in primary, secondary, and tertiary care requires well-defined competencies, implementation of training and educational programs, sharing of data, and harmonized guidelines. In this position paper, the current knowledge to understand cancer predisposition and risk factors, the cellular biology of cancer, predictive markers and treatment outcome, the improvement in technologies in screening and diagnosis, and provision of better drug development solutions are discussed in the context of a better implementation of personalized medicine. Recognition of the major risk factors for cancer initiation is the key for preventive strategies (EPMA J. 4(1):6, 2013). Of interest, cancer predisposing syndromes in particular the monogenic subtypes that lead to cancer progression are well defined and one should focus on implementation strategies to identify individuals at risk to allow preventive measures and early screening/diagnosis. Implementation of such measures is disturbed by improper use of the data, with breach of data protection as one of the risks to be heavily controlled. Population screening requires in depth cost-benefit analysis to justify healthcare costs, and the parameters screened should provide information that allow an actionable and deliverable solution, for better healthcare provision.

Tear fluid biomarker profiling: a review of multiplex bead analysis.

Developments in the field of tear film protein profiling are reviewed, including the advantages and disadvantages of the multiplex bead array technique and its potential for identifying biomarkers of ocular surface disease. Commercial kits, which specifically employ 96-well plates with polystyrene microspheres and magnetic beads, and sensitivity variations between them are discussed. Modifications to protocols of these kits (which are designed primarily for larger sample volumes, such as blood and cell culture supernatants) may be necessary for tear fluid samples. Multiplex bead array is compared to the "gold standard," ELISA. The challenges of diagnosing and monitoring dry eye disease, due to the conflicting and variable signs and symptoms presented, are illustrated by the authors' own study results. The development of a biomarker profile for the disease would be a useful approach to the ongoing problems of diagnosis. The multiplex bead array technique has important potential applications in this regard.

Raf kinase inhibitor protein expression combined with peritoneal involvement and lymphovascular invasion predicts prognosis in Dukes' B colorectal cancer patients.

AIMS: There is controversy regarding the use of adjuvant therapy in patients with Dukes' B colorectal cancer (CRC). New markers, identifying high-risk Dukes' B patients, are needed. Here, we examine the utility of Raf kinase inhibitor protein (RKIP) as such a marker and promoter methylation as a mechanism of RKIP down-regulation. METHODS AND RESULTS: We used a tissue microarray of 220 patients with Dukes' B CRC to examine the effect of RKIP expression on survival. Pyrosequencing was used to assess RKIP promoter methylation status.RKIP expression correlated inversely with disease-specific survival in this cohort. In multivariate analysis, RKIP was found to be an independent prognostic indicator, along with peritoneal invasion and lymphovascular invasion (LVI). RKIP promoter hypermethylation was seen in only one of 29 tumours analysed by pyrosequencing. CONCLUSIONS: Raf kinase inhibitor protein, peritoneal invasion and LVI provide independent prognostic information in this cohort of Dukes' B CRC patients.This demonstrates the potential utility of RKIP in identifying 'high-risk' Dukes' B patients. It is this high-risk group which is most likely to benefit from close postoperative monitoring and may derive the most benefit from adjuvant therapy.

Targeted therapies in colorectal cancer-an integrative view by PPPM.

In developed countries, colorectal cancer (CRC) is the third most common malignancy, but it is the second most frequent cause of cancer-related death. Clinicians are still faced with numerous challenges in the treatment of this disease, and future approaches which target the molecular features of the disorder will be critical for success in this disease setting. Genetic analyses of many solid tumours have shown that up to 100 protein-encoding genes are mutated. Within CRC, numerous genetic alterations have been identified in a number of pathways. Therefore, understanding the molecular pathology of CRC may present information on potential routes for treatment and may also provide valuable prognostic information. This will be particularly pertinent for molecularly targeted treatments, such as anti-vascular endothelial growth factor therapies and anti-epidermal growth factor receptor (EGFR) monoclonal antibody therapy. KRAS and BRAF mutations have been shown to predict response to anti-EGFR therapy. As EGFR can also signal via the phosphatidylinositol 3-kinase (PI3K) kinase pathway, there is considerable interest in the potential roles of members of this pathway (such as PI3K and PTEN) in predicting treatment response. Therefore, a combined approach of new techniques that allow identification of these biomarkers alongside interdisciplinary approaches to the treatment of advanced CRC will aid in the treatment decision-making process and may also serve to guide future therapeutic approaches.

Absence of xenotropic murine leukaemia virus-related virus in UK patients with chronic fatigue syndrome.

BACKGROUND: Detection of a retrovirus, xenotropic murine leukaemia virus-related virus (XMRV), has recently been reported in 67% of patients with chronic fatigue syndrome. We have studied a total of 170 samples from chronic fatigue syndrome patients from two UK cohorts and 395 controls for evidence of XMRV infection by looking either for the presence of viral nucleic acids using quantitative PCR (limit of detection <16 viral copies) or for the presence of serological responses using a virus neutralisation assay. RESULTS: We have not identified XMRV DNA in any samples by PCR (0/299). Some serum samples showed XMRV neutralising activity (26/565) but only one of these positive sera came from a CFS patient. Most of the positive sera were also able to neutralise MLV particles pseudotyped with envelope proteins from other viruses, including vesicular stomatitis virus, indicating significant cross-reactivity in serological responses. Four positive samples were specific for XMRV. CONCLUSIONS: No association between XMRV infection and CFS was observed in the samples tested, either by PCR or serological methodologies. The non-specific neutralisation observed in multiple serum samples suggests that it is unlikely that these responses were elicited by XMRV and highlights the danger of over-estimating XMRV frequency based on serological assays. In spite of this, we believe that the detection of neutralising activity that did not inhibit VSV-G pseudotyped MLV in at least four human serum samples indicates that XMRV infection may occur in the general population, although with currently uncertain outcomes.