16 research outputs found

    Implantable slot antenna with substrate integrated waveguide for biomedical applications

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    This work presents a new design of capsule slot antenna with substrate integrated waveguide (SIW) for wireless body area networks (WBANs) operating at the range of (2.5-4 GHz) which is located in the body area networks (BAN) standard in IEEE802.15.6. The proposed antenna was designed for WBANs. The substrate is assumed to be from Rogers 5880 with relative permittivity of 2.2, and thickness of 0.787 mm. The ground and the patch are created from annealed copper while the capsule is assumed to be a plastic material of medical grade polycarbonate. The antenna designed and summited using computer simulation technology (CST) software. A CST voxel model was used to study the performance of SIW capsule antenna and the ability of the band (2.5-4 GHz). Results indicated a wide bandwidth of 1.5 GHz between the range of (2.5-4) GHz at 3.3 GHz as center frequency, with return loss with more than -24.52 dB, a gain of -18.2 dB, voltage standing wave ratio (VSWR) of 1.17, and front-to-back ratio (FBR) of 10.07 dB. Through simulation, all considerable parameters associated with the proposed antenna including return loss, bandwidth, operating frequency, VSWR less than 2, radiation pattern were examined. Regarding size, gain, and frequency band, the proposed antenna is located with the standards of implantable medical devices (IMDs)

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

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    Abstract 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

    Physico-chemical characterisation and toxicological evaluation of particulate fumes produced by small calibre firing and smoke : comparative study

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    La pollution atmosphĂ©rique, et plus particuliĂšrement la pollution particulaire d’origine anthropique constitue l'un des facteurs de risque environnemental les plus importants impliquĂ©s dans l’augmentation croissante de la morbi-mortalitĂ© liĂ©e aux pathologies respiratoires et cardio-vasculaires. Au coeur du domaine qu’englobent les activitĂ©s pyrotechniques, que ce soit dans le domaine professionnel, civil ou militaire, les fumigĂšnes sont rĂ©fĂ©rencĂ©s comme producteur important de particules et jouent donc un rĂŽle non nĂ©gligeable dans l’augmentation de cette pollution particulaire, exposant leurs utilisateurs aux diffĂ©rents aĂ©rosols Ă©mis.L’objectif gĂ©nĂ©ral de cette Ă©tude exploratoire a Ă©tĂ© d’apporter des connaissances sur les caractĂ©ristiques physico-chimiques ainsi que sur la toxicitĂ© pulmonaire in vitro de particules Ă©mises lors d’activitĂ©s pyrotechniques, et plus prĂ©cisĂ©ment de particules issues d’armes de petit calibre et de fumigĂšnes.La caractĂ©risation physico-chimique a dĂ©montrĂ© les particules de tir possĂ©daient une granulomĂ©trie assez grossiĂšre (entre 3 et 7,5 ÎŒm) et Ă©taient composĂ©es majoritairement d’élĂ©ments mĂ©talliques ; contrairement aux particules de fumigĂšne qui appartiendraient Ă  la classe granulomĂ©trique des particules fines (< 0,95 ÎŒm) et qui seraient majoritairement composĂ©es de molĂ©cules organiques diffĂ©rentes selon le type de fumigĂšne. L’évaluation de la toxicitĂ© a Ă©tĂ© rĂ©alisĂ©e par une approche in vitro en utilisant des cellules Ă©pithĂ©liales alvĂ©olaires humaines (A549) exposĂ©es aux particules de tir et de fumigĂšnes. Une Ă©tude de mutagĂ©nicitĂ© a Ă©tĂ© conduite Ă  partir d’extraits organiques des particules de fumigĂšnes. Parmi les particules testĂ©es, les particules de tir et du fumigĂšne 1 ont induit une cytotoxicitĂ©. Les particules de fumigĂšne 1 ont Ă©galement induit un stress oxydant (augmentation de l’expression de l’ARNm de HO-1), une initiation de la rĂ©ponse inflammatoire (augmentation de l’expression de l’ARNm d’IL-6 et IL-8) et des effets mutagĂšnes.Les rĂ©sultats de cette Ă©tude comparative ont dĂ©montrĂ© que les particules issues d’armes de poing et de fumigĂšnes avaient une granulomĂ©trie, une concentration atmosphĂ©rique ainsi qu’une composition chimique diffĂ©rentes ; caractĂ©ristiques physico-chimiques responsables d’effets mutagĂšnes et cytotoxiques diffĂ©rents ainsi que d’altĂ©rations des propriĂ©tĂ©s oxydantes et inflammatoires intrinsĂšques. Cette Ă©tude a mis en Ă©vidence la nĂ©cessitĂ© d’évaluer la toxicitĂ© des particules issues d’activitĂ©s pyrotechniques en dĂ©veloppant des moyens expĂ©rimentaux adaptĂ©s, depuis la collecte des particules jusqu’à l’évaluation de leurs impacts sanitaires.Air pollution, and particulary anthropogenic particulate matter, is one of the most important risk factors involved in the high rate of morbidity and mortality related to respiratory and cardiovascular diseases. In pyrotechnic field, be it professional, civil or military activities, smokes constitue an important particle producer playing a major role in particulate matter emmergence and thereby exposing users to the various emitted aerosols.The main purpose of this exploratory study was to provide knowledge on the physicochemical characteristics of particles emitted during pyrotechnic activities, more specifically particles from gunfire and smokes, and to assess their pulmonary toxicity in vitro.On the first hand, the physicochemical characterization demonstrates that firing particles had a rather coarse granulometry (3 to 7.5 ÎŒm) and were mainly composed of metallic elemets, despite smoke particles belong to the category of fine particles (< 0,95 ÎŒm) and are predominantly composed of different organic molecules according to the smoke type.On the other hand, in order to assess the pulmonary toxicity of particles, we exposed human alveolar epithelial cells (A549) in vitro to particles coming from either gunfire and to two of the four different smokes (smoke 1 and 4). The results of this study showed that some of these particles (gunfire and smoke 1 particles) induced a mutagenic effects from organic extracts, as well as cytotoxicity. Moreover, particles of smoke 1 were also able to give rise to an oxidative stress (increased HO-1 mRNA expression) and to initiate an important inflammatory response characterized by pro-inflammatory cytokine upregulation (increase in IL-6 and IL-8 mRNA expression).The results of this comparative study demonstrated that particles from gunfire and smoke have different particle sizes and chemical composition. These physicochemical characteristics are responsible for different mutagenic and cytotoxic effects as well as alterations of the intrinsic oxidizing and inflammatory properties. This study also made it possible to understand the different methods of toxicological evaluation of smoke particles

    Caractérisation physico-chimique et évaluation toxicologique de fumées particulaires produites lors de tirs de petit calibre et de fumigÚnes : étude comparative

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    Air pollution, and particulary anthropogenic particulate matter, is one of the most important risk factors involved in the high rate of morbidity and mortality related to respiratory and cardiovascular diseases. In pyrotechnic field, be it professional, civil or military activities, smokes constitue an important particle producer playing a major role in particulate matter emmergence and thereby exposing users to the various emitted aerosols.The main purpose of this exploratory study was to provide knowledge on the physicochemical characteristics of particles emitted during pyrotechnic activities, more specifically particles from gunfire and smokes, and to assess their pulmonary toxicity in vitro.On the first hand, the physicochemical characterization demonstrates that firing particles had a rather coarse granulometry (3 to 7.5 ÎŒm) and were mainly composed of metallic elemets, despite smoke particles belong to the category of fine particles (< 0,95 ÎŒm) and are predominantly composed of different organic molecules according to the smoke type.On the other hand, in order to assess the pulmonary toxicity of particles, we exposed human alveolar epithelial cells (A549) in vitro to particles coming from either gunfire and to two of the four different smokes (smoke 1 and 4). The results of this study showed that some of these particles (gunfire and smoke 1 particles) induced a mutagenic effects from organic extracts, as well as cytotoxicity. Moreover, particles of smoke 1 were also able to give rise to an oxidative stress (increased HO-1 mRNA expression) and to initiate an important inflammatory response characterized by pro-inflammatory cytokine upregulation (increase in IL-6 and IL-8 mRNA expression).The results of this comparative study demonstrated that particles from gunfire and smoke have different particle sizes and chemical composition. These physicochemical characteristics are responsible for different mutagenic and cytotoxic effects as well as alterations of the intrinsic oxidizing and inflammatory properties. This study also made it possible to understand the different methods of toxicological evaluation of smoke particles.La pollution atmosphĂ©rique, et plus particuliĂšrement la pollution particulaire d’origine anthropique constitue l'un des facteurs de risque environnemental les plus importants impliquĂ©s dans l’augmentation croissante de la morbi-mortalitĂ© liĂ©e aux pathologies respiratoires et cardio-vasculaires. Au coeur du domaine qu’englobent les activitĂ©s pyrotechniques, que ce soit dans le domaine professionnel, civil ou militaire, les fumigĂšnes sont rĂ©fĂ©rencĂ©s comme producteur important de particules et jouent donc un rĂŽle non nĂ©gligeable dans l’augmentation de cette pollution particulaire, exposant leurs utilisateurs aux diffĂ©rents aĂ©rosols Ă©mis.L’objectif gĂ©nĂ©ral de cette Ă©tude exploratoire a Ă©tĂ© d’apporter des connaissances sur les caractĂ©ristiques physico-chimiques ainsi que sur la toxicitĂ© pulmonaire in vitro de particules Ă©mises lors d’activitĂ©s pyrotechniques, et plus prĂ©cisĂ©ment de particules issues d’armes de petit calibre et de fumigĂšnes.La caractĂ©risation physico-chimique a dĂ©montrĂ© les particules de tir possĂ©daient une granulomĂ©trie assez grossiĂšre (entre 3 et 7,5 ÎŒm) et Ă©taient composĂ©es majoritairement d’élĂ©ments mĂ©talliques ; contrairement aux particules de fumigĂšne qui appartiendraient Ă  la classe granulomĂ©trique des particules fines (< 0,95 ÎŒm) et qui seraient majoritairement composĂ©es de molĂ©cules organiques diffĂ©rentes selon le type de fumigĂšne. L’évaluation de la toxicitĂ© a Ă©tĂ© rĂ©alisĂ©e par une approche in vitro en utilisant des cellules Ă©pithĂ©liales alvĂ©olaires humaines (A549) exposĂ©es aux particules de tir et de fumigĂšnes. Une Ă©tude de mutagĂ©nicitĂ© a Ă©tĂ© conduite Ă  partir d’extraits organiques des particules de fumigĂšnes. Parmi les particules testĂ©es, les particules de tir et du fumigĂšne 1 ont induit une cytotoxicitĂ©. Les particules de fumigĂšne 1 ont Ă©galement induit un stress oxydant (augmentation de l’expression de l’ARNm de HO-1), une initiation de la rĂ©ponse inflammatoire (augmentation de l’expression de l’ARNm d’IL-6 et IL-8) et des effets mutagĂšnes.Les rĂ©sultats de cette Ă©tude comparative ont dĂ©montrĂ© que les particules issues d’armes de poing et de fumigĂšnes avaient une granulomĂ©trie, une concentration atmosphĂ©rique ainsi qu’une composition chimique diffĂ©rentes ; caractĂ©ristiques physico-chimiques responsables d’effets mutagĂšnes et cytotoxiques diffĂ©rents ainsi que d’altĂ©rations des propriĂ©tĂ©s oxydantes et inflammatoires intrinsĂšques. Cette Ă©tude a mis en Ă©vidence la nĂ©cessitĂ© d’évaluer la toxicitĂ© des particules issues d’activitĂ©s pyrotechniques en dĂ©veloppant des moyens expĂ©rimentaux adaptĂ©s, depuis la collecte des particules jusqu’à l’évaluation de leurs impacts sanitaires

    Role of M2-like macrophage recruitment during angiogenic growth factor therapy

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    International audienceTherapeutic angiogenesis has yet to fulfill its promise for the clinical treatment of ischemic diseases. Given the impact of macrophages during pathophysiological angiogenesis, we asked whether macrophages may similarly modulate vascular responses to targeted angiogenic therapies. Mouse matrigel plug assay and rat myocardial infarction (MI) model were used to assess angiogenic therapy with either VEGF-A or FGF-2 with HGF (F+H) delivered locally via albumin-alginate microcapsules. The infiltration of classical M1-type and alternative M2-like macrophages was assessed. Clodronate was used to prevent macrophage recruitment, and the VEGFR2 blocking antibody, DC101, to prevent VEGF-A signaling. At 3 weeks after matrigel implantation, the combination therapy (F+H) led to increased total, and specifically M2-like, macrophage infiltration versus control and VEGF-A plugs, correlating with the angiogenic response. In contrast, VEGF-A preferential recruited M1-type macrophages. In agreement with a direct role of M2-like macrophages in F+H-induced vessel growth, clodronate radically decreased angiogenesis. Further, DC101 reduced F+H-induced angiogenesis, without altering macrophage infiltration, revealing macrophage-derived VEGF-A as a crucial determinant of tissue responsiveness. Similarly, increased cardiac M2-like macrophage infiltration was found following F+H therapy post-MI, with strong correlation between macrophage levels and angiogenic and arteriogenic responses. In conclusion, M2-like macrophages play a decisive role, linked to VEGF-A production, in regulation of tissue responsiveness to angiogenic therapies including the combination of F+H. Our data suggest that future attempts at therapeutic revascularization in ischemic patients might benefit from coupling targeted growth factor delivery with either direct or indirect approaches to recruit pro-angiogenic macrophages in order to maximize therapeutic angiogenic/arteriogenic responses

    Implantable slot antenna with substrate integrated waveguide for biomedical applications

    Get PDF
    This work presents a new design of capsule slot antenna with substrate integrated waveguide (SIW) for wireless body area networks (WBANs) operating at the range of (2.5-4 GHz) which is located in the body area networks (BAN) standard in IEEE802.15.6. The proposed antenna was designed for WBANs. The substrate is assumed to be from Rogers 5880 with relative permittivity of 2.2, and thickness of 0.787 mm. The ground and the patch are created from annealed copper while the capsule is assumed to be a plastic material of medical grade polycarbonate. The antenna designed and summited using computer simulation technology (CST) software. A CST voxel model was used to study the performance of SIW capsule antenna and the ability of the band (2.5-4 GHz). Results indicated a wide bandwidth of 1.5 GHz between the range of (2.5-4) GHz at 3.3 GHz as center frequency, with return loss with more than -24.52 dB, a gain of -18.2 dB, voltage standing wave ratio (VSWR) of 1.17, and front-to-back ratio (FBR) of 10.07 dB. Through simulation, all considerable parameters associated with the proposed antenna including return loss, bandwidth, operating frequency, VSWR less than 2, radiation pattern were examined. Regarding size, gain, and frequency band, the proposed antenna is located with the standards of implantable medical devices (IMDs)
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