50 research outputs found

    Diagnostic assessment of foetal brain malformations with intra-uterine MRI versus perinatal post-mortem MRI

    Get PDF
    PURPOSE: To evaluate differences in diagnostic yield of intra-uterine foetal (iuMR) and post-mortem MRI (PMMR) for complex brain malformations, using autopsy as the reference standard. METHODS: In this retrospective, multicentre study spanning 2 years, we reviewed 13 terminated singleton pregnancies with a prenatal ultrasound finding of complex foetal cerebral abnormalities, referred for both iuMR and PMMR. The iuMR and PMMR studies of the brain were reported independently by two groups of radiologists, blinded to each other's reports. Descriptive statistics were used to compare differences in intracranial abnormalities with autopsy (and genetic testing, where present) as reference standard. RESULTS: The median gestational age at termination was 24.6 weeks (IQR 22-29) with median time between delivery and PMMR of 133 h (IQR 101-165). There was full concordance between iuMR and PMMR findings and autopsy in 2/13 (15.3%) cases. Partial concordance between both imaging modalities was present in 6/13 (46.2%) and total discordance in the remainder (5/13, 38.5%). When compared to autopsy, PMMR missed important key findings specifically for neuronal migration and cerebellar anomalies, whereas iuMR appeared to overcall CSF space abnormalities which were less crucial to reaching the final overall diagnosis. CONCLUSIONS: iuMR should be performed to improve foetal phenotyping where there is a prenatal ultrasound for complex foetal brain abnormalities. Reliance on PMMR alone is likely to result in misdiagnosis in a majority of cases

    In vivo comparison of the proangiogenic properties of chlordecone and three of its dechlorinated derivatives formed by in situ chemical reduction

    Get PDF
    In situ chemical reduction (ISCR) has been identified as a possible way for the remediation of soils contaminated by chlordecone (CLD). Evidences provided by the literature indicate an association between the development of prostate cancer and CLD exposure (Multigner et al. 2010). In a previous in vitro study, we demonstrated that the two main dechlorinated CLD derivatives formed by ISCR, CLD-1Cl, and CLD-3Cl have lower cytotoxicity and proangiogenic properties than CLD itself (Legeay et al. 2017). By contrast, nothing is known on the in vivo proangiogenic effect of these dechlorinated derivatives. Based on in vitro data, the aims of this study were therefore to evaluate the in vivo influence of CLD and three of its dechlorinated metabolites in the control of neovascularization in a mice model of prostate cancer. The proangiogenic effect of CLD and three of its dechlorinated derivatives, CLD-1Cl, CLD-3Cl, and CLD-4Cl, was evaluated on a murine model of human prostate tumor (PC-3) treated, at two exposure levels: 33 μg/kg and 1.7 μg/kg respectively reflecting acute and chronic toxic exposure in human. The results of serum measurements show that, for the same ingested dose, the three metabolite concentrations were significantly lower than that of CLD. Dechlorination of CLD lead therefore to molecules that are biologically absorbed or metabolized, or both, faster than the parent molecule. Prostate tumor growth was lower in the groups treated by the three metabolites compared to the one treated by CLD. The vascularization measured on the tumor sections was inversely proportional to the rate of dechlorination, the treatment with CLD-4Cl showing no difference with control animals treated with only the vehicle oil used for all substances tested. We can therefore conclude that the proangiogenic effect of CLD is significantly decreased following the ISCR-resulting dechlorination. Further investigations are needed to elucidate the molecular mechanisms by which dechlorination of CLD reduces proangiogenic effects in prostate tumor

    Inflammatory, Hemostatic, and Other Novel Biomarkers for Diabetic Retinopathy: The Multi-Ethnic Study of Atherosclerosis

    Get PDF
    Objective— There are conflicting data regarding relationships of systemic biomarkers of inflammation, hemostasis, and homocysteine with diabetic retinopathy. We examined these relationships in the Multi-Ethnic Study of Atherosclerosis. Research design and methods— A total of 921 participants with diabetes were included. Diabetic retinopathy was graded from retinal photographs. We defined two outcomes: any diabetic retinopathy and vision-threatening diabetic retinopathy (severe nonproliferative diabetic retinopathy or worse). Systemic markers analyzed were C-reactive protein, homocysteine, fibrinogen, plasmin- 2-antiplasmin complex (PAP), interleukin-6, D-dimer, factor VIII, serum creatinine, and urinary albumin-to-creatinine (UAC) ratio. Results— Prevalence of diabetic retinopathy was 33.2% and vision-threatening diabetic retinopathy 7.1%. After adjusting for established risk factors (diabetes duration, A1C, systolic blood pressure, waist-to-hip ratio, and use of diabetes medications), fibrinogen (odds ratio 1.14 [95% CI 1.01–1.32], P 0.05) and PAP (1.25 [1.05–1.50], P0.01) were associated with any diabetic retinopathy, while PAP (1.54 [1.13–2.11], P 0.007) and homocysteine (1.57 [1.16– 2.11], P 0.003) were associated with vision-threatening diabetic retinopathy. Only PAP remained significant after additional adjustment for serum creatinine and UAC ratio. Area under receiver-operator characteristic curve (AUROC) for diabetic retinopathy was constructed for established and novel risk factors. Established risk factors accounted for a 39.2% increase of the AUROC, whereas novel markers (fibrinogen, PAP, homocysteine, serum creatinine, and UAC ratio) only accounted for an additional 2.2%. Conclusions— There were few associations of novel markers of inflammation, hemostasis, and homocysteine with diabetic retinopathy after controlling for established risk factors. These data suggest that there is limited clinical use of these biomarkers for prediction of diabetic retinopathy

    PloS one

    Get PDF
    The vasculoprotective properties of delphinidin are driven mainly by its action on endothelial cells. Moreover, delphinidin displays anti-angiogenic properties in both in vitro and in vivo angiogenesis models and thereby might prevent the development of tumors associated with excessive vascularization. This study was aimed to test the effect of delphinidin on melanoma-induced tumor growth with emphasis on its molecular mechanism on endothelial cells. Delphinidin treatment significantly decreased in vivo tumor growth induced by B16-F10 melanoma cell xenograft in mice. In vitro, delphinidin was not able to inhibit VEGFR2-mediated B16-F10 melanoma cell proliferation but it specifically reduced basal and VEGFR2-mediated endothelial cell proliferation. The anti-proliferative effect of delphinidin was reversed either by the MEK1/2 MAP kinase inhibitor, U-0126, or the PI3K inhibitor, LY-294002. VEGF-induced proliferation was reduced either by U-0126 or LY-294002. Under these conditions, delphinidin failed to decrease further endothelial cell proliferation. Delphinidin prevented VEGF-induced phosphorylation of ERK1/2 and p38 MAPK and decreased the expression of the transcription factors, CREB and ATF1. Finally, delphinidin was more potent in inhibiting in vitro cyclic nucleotide phosphodiesterases (PDEs), PDE1 and PDE2, compared to PDE3-PDE5. Altogether delphinidin reduced tumor growth of melanoma cell in vivo by acting specifically on endothelial cell proliferation. The mechanism implies an association between inhibition of VEGF-induced proliferation via VEGFR2 signalling, MAPK, PI3K and at transcription level on CREB/ATF1 factors, and the inhibition of PDE2. In conjunction with our previous studies, we demonstrate that delphinidin is a promising compound to prevent pathologies associated with generation of vascular network in tumorigenesis

    The association between retinal vascular geometry changes and diabetic retinopathy and their role in prediction of progression: an exploratory study

    Get PDF
    Background: The study describes the relationship of retinal vascular geometry (RVG) to severity of diabetic retinopathy (DR), and its predictive role for subsequent development of proliferative diabetic retinopathy (PDR). Methods. The research project comprises of two stages. Firstly, a comparative study of diabetic patients with different grades of DR. (No DR: Minimal non-proliferative DR: Severe non-proliferative DR: PDR) (10:10: 12: 19). Analysed RVG features including vascular widths and branching angles were compared between patient cohorts. A preliminary statistical model for determination of the retinopathy grade of patients, using these features, is presented. Secondly, in a longitudinal predictive study, RVG features were analysed for diabetic patients with progressive DR over 7 years. RVG at baseline was examined to determine risk for subsequent PDR development. Results: In the comparative study, increased DR severity was associated with gradual vascular dilatation (p = 0.000), and widening of the bifurcating angle (p = 0.000) with increase in smaller-child-vessel branching angle (p = 0.027). Type 2 diabetes and increased diabetes duration were associated with increased vascular width (p = <0.05 In the predictive study, at baseline, reduced small-child vascular width (OR = 0.73 (95 CI 0.58-0.92)), was predictive of future progression to PDR. Conclusions: The study findings suggest that RVG alterations can act as novel markers indicative of progression of DR severity and establishment of PDR. RVG may also have a potential predictive role in determining the risk of future retinopathy progression. © 2014 Habib et al.; licensee BioMed Central Ltd

    The status of hepatitis C virus infection among people who inject drugs in the Middle East and North Africa.

    Get PDF
    BACKGROUND AND AIMS: People who inject drugs (PWID) are a key population at high risk of hepatitis C virus (HCV) infection. The aim of this study was to delineate the epidemiology of HCV in PWID in the Middle East and North Africa (MENA). METHODS: Syntheses of data were conducted on the standardized and systematically assembled databases of the MENA HCV Epidemiology Synthesis Project, 1989-2018. Random-effects meta-analyses and meta-regressions were performed. Meta-regression variables included country, study site, year of data collection and year of publication [to assess trends in HCV antibody prevalence over time], sample size and sampling methodology. Numbers of chronically infected PWID across MENA were estimated. The Shannon Diversity Index was calculated to assess genotype diversity. RESULTS: Based on 118 HCV antibody prevalence measures, the pooled mean prevalence in PWID for all MENA was 49.3% [95% confidence interval (CI) = 44.4-54.1%]. The country-specific pooled mean ranged from 21.7% (95% CI = 4.9-38.6%) in Tunisia to 94.2% (95% CI = 90.8-96.7%) in Libya. An estimated 221 704 PWID were chronically infected, with the largest numbers found in Iran at 68 526 and in Pakistan at 46 554. There was no statistically significant evidence for a decline in HCV antibody prevalence over time. Genotype diversity was moderate (Shannon Diversity Index of 1.01 out of 1.95; 52.1%). The pooled mean percentage for each HCV genotype was highest in genotype 3 (42.7%) and in genotype 1 (35.9%). CONCLUSION: Half of people who inject drugs in the Middle East and North Africa appear to have ever been infected with hepatitis C virus, but there are large variations in antibody prevalence among countries. In addition to > 200 000 chronically infected current people who inject drugs, there is an unknown number of people who no longer inject drugs who may have acquired hepatitis C virus during past injecting drug use. Harm reduction services must be expanded, and innovative strategies need to be employed to ensure accessibility to hepatitis C virus testing and treatment

    Separation and recovery of critical metal ions using ionic liquids

    Get PDF
    Separation and purification of critical metal ions such as rare-earth elements (REEs), scandium and niobium from their minerals is difficult and often determines if extraction is economically and environmentally feasible. Solvent extraction is a commonly used metal-ion separation process, usually favored because of its simplicity, speed and wide scope, which is why it is often employed for separating trace metals from their minerals. However, the types of solvents widely used for the recovery of metal ions have adverse environmental impact. Alternatives to solvent extraction have been explored and advances in separation technologies have seen commercial establishment of liquid membranes as an alternative to conventional solvent extraction for the recovery of metals and other valuable materials. Liquid membrane transport incorporates solvent extraction and membrane separation in one continuously operating system. Both methods conventionally use solvents that are harmful to the environment, however, the introduction of ionic liquids (ILs) over the last decade is set to minimize the environmental impact of both solvent extraction and liquid membrane separation processes. ILs are a family of organic molten salts with low or negligible vapour pressure which may be formed below 100 oC. Such liquids are also highly thermally stable and less toxic. Their ionic structure makes them thermodynamically favorable solvents for the extraction of metallic ions. The main aim of this article is to review the current achievements in the separation of REE, scandium, niobium and vanadium from their minerals, using ILs in either solvent extraction or liquid membrane processes. The mechanism of separation using ILs is discussed and the engineering constraints to their application are identified

    Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

    Get PDF
    Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

    Retinal Vascular Caliber and Risk of Retinopathy in Young Patients with Type 1 Diabetes

    No full text
    10.1016/j.ophtha.2006.05.009Ophthalmology11391499-1503OPHT
    corecore