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1.
BMJ Mil Health ; 170(2): 150-154, 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38508774

RESUMEN

The UK military prehospital emergency care (PHEC) operational clinical capability framework must be updated in order that it retains its use as a valid operational planning tool. Specific requirements include accurately defining the PHEC levels and the 'Medical Emergency Response Team' (MERT), while reinforcing PHEC as a specialist area of clinical practice that requires an assured set of competencies at all levels and mandatory clinical currency for vocational providers.A military PHEC review panel was convened by the Defence Consultant Advisor (DCA) for PHEC. Each PHEC level was reviewed and all issues which had, or could have arisen from the existing framework were discussed until agreement between the six members of this panel was established.An updated military PHEC framework has been produced by DCA PHEC, which defines the minimum requirements for each operational PHEC level. These definitions cover all PHEC providers, irrespective of professional background. The mandatory requirement for appropriate clinical exposure for vocational and specialist providers is emphasised. An updated definition of MERT has been agreed.This update provides clarity to the continually evolving domain of UK military PHEC. It sets out the PHEC provider requirements in order to be considered operationally deployable in a PHEC role. There are implications for training, manning and recruitment to meet these requirements, but the processes required to address these are already underway and well described elsewhere.


Asunto(s)
Cisteína/análogos & derivados , Servicios Médicos de Urgencia , Medicina Militar , Personal Militar , Humanos , Medicina Militar/educación , Reino Unido
2.
Biomaterials ; 289: 121797, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-36156410

RESUMEN

Biomaterial characteristics like surface roughness and wettability can determine the phenotype of macrophages following implantation. We have demonstrated that inhibiting Wnt ligand secretion abolishes macrophage polarization in vitro and in vivo; however, the role of canonical Wnt signaling in macrophage activation in response to physical and chemical biomaterial cues is unknown. The aim of this study was to understand whether canonical Wnt signaling affects the response of macrophages to titanium (Ti) surface roughness or wettability in vitro and in vivo. Activating canonical Wnt signaling increased expression of toll-like receptors and interleukin receptors and secreted pro-inflammatory cytokines and reduced anti-inflammatory cytokines on Ti, regardless of surface properties. Inhibiting canonical Wnt signaling reduced pro-inflammatory cytokines on all Ti surfaces and increased anti-inflammatory cytokines on rough or rough-hydrophilic Ti. In vivo, activating canonical Wnt signaling increased total macrophages, pro-inflammatory macrophages, and T cells and decreased anti-inflammatory macrophages on both smooth and rough-hydrophilic implants. Functionally, canonical Wnt activation increases pro-inflammatory macrophage response to cell and cell-extracellular matrix lysates. These results demonstrate that activating canonical Wnt signaling primes macrophages to a pro-inflammatory phenotype that affects their response to Ti implants in vitro and in vivo.


Asunto(s)
Titanio , Vía de Señalización Wnt , Antiinflamatorios/metabolismo , Materiales Biocompatibles/química , Citocinas/metabolismo , Ligandos , Macrófagos/metabolismo , Propiedades de Superficie , Titanio/química , Titanio/farmacología
3.
Am J Med ; 135(10): 1158-1167.e3, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35472383

RESUMEN

Health care policymaking during the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has questioned the precedent of restricting hospital visitors. We aimed to synthesize available data describing the resulting impact on patient, family/visitor, and health care provider well-being. We systematically reviewed articles from the World Health Organization COVID-19 Global Literature on Coronavirus Disease Database published between December 2019 through April 2021. Included studies focused on hospitalized patients and reported 1 or more prespecified main or secondary outcome (coronavirus disease 2019 [COVID-19] disease transmission, global well-being, mortality, morbidity, or health care resource utilization). Two authors independently extracted data into a standardized form with a third author resolving discrepancies. A total of 1153 abstracts were screened, and 26 final full-text articles were included. Ten studies were qualitative, with 7 cohort studies, and no randomized controlled trials. Critically ill patients were the most represented (12 out of 26 studies). Blanket hospital visitor policies were associated with failure to address the unique needs of patients, their visitors, and health care providers in various clinical environments. Overall, a patient-centered, thoughtful, and nuanced approach to hospital visitor policies is likely to benefit all stakeholders while minimizing potential harms.


Asunto(s)
COVID-19 , Pandemias , COVID-19/prevención & control , Personal de Salud , Hospitales , Humanos , Pandemias/prevención & control , Políticas , SARS-CoV-2
4.
Materialia (Oxf) ; 202021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34778733

RESUMEN

OBJECTIVES: Smoking is a known contributor to the failure of dental implants. Despite a decline in cigarette use, the popularity of e-cigarettes has exploded. However, little is known about how e-cigarettes affect the biologic response to implants. This study examines the effect of e-cigarette aerosol mixtures (ecig-AM) on macrophage activation and osteoblastogenesis of mesenchymal stem cells (MSCs) in response to titanium (Ti) implant surfaces. METHODS: Ecig-AMs were prepared by bubbling aerosol through PBS. Human-derived MSCs or murine-derived macrophages were plated on smooth, rough-hydrophobic, or rough-hydrophilic Ti surfaces in media supplemented with ecig-AM. In macrophages, expression of inflammatory markers was measured by qPCR and macrophage immunophenotype characterized by flow cytometry after 24 hours of exposure. In MSCs, expression of osteogenic markers and inflammatory cytokines was measured by qPCR and ELISA, while alkaline phosphatase activity (ALP) was determined by colorimetric assay. RESULTS: Ecig-AM polarized primary macrophages into a pro-inflammatory state with higher effect on ecig-AM with flavorants and nicotine. Metabolic activity of MSCs decreased in a concentration dependent fashion and was stronger in ecig-AM containing nicotine. MSCs reduced expression of osteogenic markers in response to ecig-AM, but increased RANKL secretion, particularly at the highest ecig-AM concentrations. The effect of ecig-AM exposure was lessened when macrophages or MSCs were cultured on rough-hydrophilic substrates. SIGNIFICANCE: Ecig-AM activated macrophages into a pro-inflammatory phenotype and impaired MSC-to-osteoblast differentiation in response to Ti implant surfaces. These effects were potentiated by flavorants and nicotine, suggesting that e-cigarette use may compromise the osseointegration of dental implants.

5.
Acta Biomater ; 133: 58-73, 2021 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-33882355

RESUMEN

As the focus of implantable biomaterials has shifted from bioinert implants to bioactive designs, recent research has highlighted the complex interactions between cell physiologic systems and material properties, particularly physical cues. From the cells known to interact with implanted biomaterials, the response of the immune system has been a critical target of study recently. Here, we review studies characterizing the response of innate immune cells to various material cues, particularly of those at the surface of implanted materials.The innate immune system consists of cell types with various roles in inflammation. Neutrophils and macrophages serve both phagocytic and signaling roles, especially early in the inflammatory phase of biomaterial implantation. These cell types ultimately dictate the outcome of implants as chronic inflammation, fibrosis, or integration. Other cell types like dendritic cells, mast cells, natural killer cells, and innate lymphoid cells may also serve an immunomodulatory role in the biomaterial context. This review highlights recent advances in our understanding of the role of innate immunity in the response to implantable biomaterials as well as key mechanobiological findings in innate immune cells underpinning these advances. STATEMENT OF SIGNIFICANCE: This review highlights recent advances in the understanding of the role of innate immunity in the response to implantable biomaterials, especially in neutrophils and macrophages, as well as key mechanobiological findings in innate immune cells underpinning these advances. Here we discuss how physicochemical properties of biomaterials control innate immune cell behavior.


Asunto(s)
Materiales Biocompatibles , Inmunidad Innata , Linfocitos , Macrófagos , Prótesis e Implantes
6.
Biomaterials ; 271: 120715, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33677375

RESUMEN

Neutrophils predominate the early inflammatory response to tissue injury and implantation of biomaterials. Recent studies have shown that neutrophil activation can be regulated by mechanical cues such as stiffness or surface wettability; however, it is not known how neutrophils sense and respond to physical cues, particularly how they form neutrophil extracellular traps (NET formation). To examine this, we used polydimethylsiloxane (PDMS) substrates of varying physiologically relevant stiffness (0.2-32 kPa) and examined the response of murine neutrophils to untreated surfaces or to surfaces coated with various extracellular matrix proteins recognized by integrin heterodimers (collagen, fibronectin, laminin, vitronectin, synthetic RGD). Neutrophils on higher stiffness PDMS substrates had increased NET formation and higher secretion of pro-inflammatory cytokines and chemokines. Extracellular matrix protein coatings showed that fibronectin induced the most NET formation and this effect was stiffness dependent. Synthetic RGD peptides induced similar levels of NET formation and pro-inflammatory cytokine release than the full-length fibronectin protein. To determine if the observed NET formation in response to substrate stiffness required focal adhesion kinase (FAK) activity, which is down stream of integrin activation, FAK inhibitor PF-573228 was used. Inhibition of FAK using PF-573228 ablated the stiffness-dependent increase in NET formation and pro-inflammatory molecule secretion. These findings demonstrate that neutrophils regulate NET formation in response to physical and mechanical biomaterial cues and this process is regulated through integrin/FAK signaling.


Asunto(s)
Trampas Extracelulares , Animales , Adhesión Celular , Proteínas de la Matriz Extracelular , Quinasa 1 de Adhesión Focal , Proteína-Tirosina Quinasas de Adhesión Focal , Integrinas , Ratones , Neutrófilos
7.
Clin Oral Implants Res ; 32(4): 487-497, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33502059

RESUMEN

OBJECTIVES: Biomaterial implantation provokes an inflammatory response that controls integrative fate. M2 macrophages regulate the response to implants by resolving the inflammatory phase and recruiting progenitor cells to aid healing. We have previously shown that modified titanium (Ti) disks directly induce M2 macrophage polarization. The aim of this study was to examine macrophage response to commercially available Ti or Ti alloy implants with comparable roughness and varying hydrophilicity. MATERIAL AND METHODS: Eleven commercially available Ti (A-F) or Ti alloy (G-K) dental implants were examined in this study. Surface topography, chemistry, and hydrophilicity were characterized for each implant. To compare the immune response in vitro, human monocyte-derived macrophages were seeded on implants and secreted pro- and anti-inflammatory proteins measured. To evaluate the inflammatory response in vivo, mice were subcutaneously instrumented with clinical implants, and implant adherent macrophage populations were characterized by flow cytometry. RESULTS: Macrophages on hydrophobic Implant C produced the highest level of pro-inflammatory proteins in vitro. In contrast, hydrophilic Implant E produced the second-highest pro-inflammatory response. Implants F and K, both hydrophilics, produced the highest anti-inflammatory protein secretions. Likewise, pro-inflammatory CD80hi macrophages predominated in vivo on implants C and E, and M2 CD206 + macrophages predominated on implants F and K. CONCLUSIONS: These findings show that hydrophilicity alone is insufficient to predict the anti-inflammatory effect on macrophage polarization and that other properties-surface composition or topography-determine immune modulation. This in vivo model may be a useful screening method to compare the immunomodulatory response to clinical implants of disparate geometry or size.


Asunto(s)
Implantes Dentales , Animales , Activación de Macrófagos , Macrófagos , Ratones , Propiedades de Superficie , Titanio
8.
Biomaterials ; 243: 119920, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32179303

RESUMEN

Macrophages are among the first cells to interact with biomaterials and ultimately determine their integrative fate. Biomaterial surface characteristics like roughness and hydrophilicity can activate macrophages to an anti-inflammatory phenotype. Wnt signaling, a key cell proliferation and differentiation pathway, has been associated with dysregulated macrophage activity in disease. However, the role Wnt signaling plays in macrophage activation and response to biomaterials is unknown. The aim of this study was to characterize the regulation of Wnt signaling in macrophages during classical pro- and anti-inflammatory polarization and in their response to smooth, rough, and rough-hydrophilic titanium (Ti) surfaces. Peri-implant Wnt signaling in macrophage-ablated (MaFIA) mice instrumented with intramedullary Ti rods was significantly attenuated compared to untreated controls. Wnt ligand mRNA were upregulated in a surface modification-dependent manner in macrophages isolated from the surface of Ti implanted in C57Bl/6 mice. In vitro, Wnt mRNAs were regulated in primary murine bone-marrow-derived macrophages cultured on Ti in a surface modification-dependent manner. When macrophageal Wnt secretion was inhibited, macrophage sensitivity to both physical and biological stimuli was abrogated. Loss of macrophage-derived Wnts also impaired recruitment of mesenchymal stem cells and T-cells to Ti implants in vivo. Finally, inhibition of integrin signaling decreased surface-dependent upregulation of Wnt genes. These results suggest that Wnt signaling regulates macrophage response to biomaterials and that macrophages are an important source of Wnt ligands during inflammation and healing.


Asunto(s)
Materiales Biocompatibles , Activación de Macrófagos , Animales , Macrófagos , Ratones , Propiedades de Superficie , Titanio , Vía de Señalización Wnt
9.
Biomater Sci ; 8(8): 2289-2299, 2020 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-32163073

RESUMEN

Biomaterial implantation triggers an immune response initially predominated by neutrophils, which activate an inflammatory cascade by producing cytokines, enzymes, immune cell recruitment chemokines, and DNA fiber networks called neutrophil extracellular traps (NETs). While the role of neutrophils has been studied extensively in infection, little is known of their role in the response to biomaterials, in this case titanium (Ti) implants. Furthermore, while implant surface modifications have been shown to attenuate pro-inflammatory polarization in other immune cells, their effects on neutrophil behavior is unknown. The aim of this study was to characterize the neutrophil response to Ti surface topography and hydrophilicity and understand how the products of biomaterial-induced neutrophil activation alters macrophage polarization. Murine neutrophils were isolated by density gradient centrifugation and plated on smooth, rough, and rough hydrophilic (rough-hydro) Ti surfaces. Neutrophils on rough-hydro Ti decreased pro-inflammatory cytokine and enzyme production as well as decreased NET formation compared to neutrophils on smooth and rough Ti. Conditioned media (CM) from neutrophils on smooth Ti enhanced pro-inflammatory macrophage polarization compared to CM from neutrophils on rough or rough-hydro Ti; pretreatment of neutrophils with a pharmacological NETosis inhibitor impaired this macrophage stimulation. Finally, co-culture of neutrophils and macrophages on Ti surfaces induced pro-inflammatory macrophage polarization compared to macrophages alone on surfaces, but this effect was ablated when neutrophils were pretreated with the NETosis inhibitor. These findings demonstrate that neutrophils are sensitive to changes in biomaterial surface properties and exhibit differential activation in response to Ti surface cues. Additionally, inhibition of NETosis enhanced anti-inflammatory macrophage polarization, suggesting NETosis as a possible therapeutic target for enhancing implant integration.


Asunto(s)
Neutrófilos/fisiología , Titanio/química , Animales , Materiales Biocompatibles , Células Cultivadas , Técnicas de Cocultivo , Citocinas/metabolismo , Trampas Extracelulares , Interacciones Hidrofóbicas e Hidrofílicas , Inflamación , Macrófagos/fisiología , Masculino , Ratones Endogámicos C57BL , Propiedades de Superficie
10.
Comput Struct Biotechnol J ; 17: 1066-1074, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31452859

RESUMEN

Lignin peroxidase (LiP) and its natural substrate veratryl alcohol (VA) play a crucial role in lignin degradation by white-rot fungi. Understanding the molecular determinants for the interaction of this enzyme with its substrates is essential in the rational design of engineered peroxidases for biotechnological application. Here, we combine computational and experimental approaches to analyze the interaction of Phanerochaete chrysosporium LiP (isoenzyme H8) with VA and its radical cation (VA•+, resulting from substrate oxidation by the enzyme). Interaction energy calculations at semiempirical quantum mechanical level (SQM) between LiP and VA/VA•+ enabled to identify those residues at the acidic environment of catalytic Trp171 involved in the main interactions. Then, a battery of variants, with single and multiple mutations at these residues (Glu168, Asp165, Glu250, Asp264, and Phe267), was generated by directed mutagenesis, and their kinetics parameters were estimated on VA and two additional substrates. The experimental results show that Glu168 and Glu250 are crucial for the binding of VA, with Glu250 also contributing to the turnover of the enzyme. The experimental results were further rationalized through new calculations of interaction energies between VA/VA•+ and LiP with each of the single mutations. Finally, the delocalization of spin density was determined with quantum mechanics/molecular mechanics calculations (QM/MM), further supporting the contribution of Glu250 to VA oxidation at Trp171.

11.
An. acad. bras. ciênc ; 90(1): 449-459, Mar. 2018. tab, graf
Artículo en Inglés | LILACS | ID: biblio-886902

RESUMEN

ABSTRACT This study evaluated the chemical composition and antioxidant activity of fatty acids from the marine red algae Pterocladiella capillacea (S. G. Gmelin) Santelices & Hommersand 1997 and Osmundaria obtusiloba (C. Agardh) R. E. Norris 1991. The gas chromatography mass spectrometry (GC-MS) identified nine fatty acids in the two species. The major fatty acids of P. capillacea and O. obtusiloba were palmitic acid, oleic acid, arachidonic acid and eicosapentaenoic acid. The DPPH radical scavenging capacity of fatty acids was moderate ranging from 25.90% to 29.97%. Fatty acids from P. capillacea (31.18%) had a moderate ferrous ions chelating activity (FIC), while in O. obtusiloba (17.17%), was weak. The ferric reducing antioxidant power (FRAP) of fatty acids from P. capillacea and O. obtusiloba was low. As for β-carotene bleaching (BCB), P. capillacea and O. obtusiloba showed a good activity. This is the first report of the antioxidant activities of fatty acids from the marine red algae P. capillacea and O. obtusiloba.


Asunto(s)
Rhodophyta/química , Ácidos Grasos/análisis , Ácidos Grasos/química , Antioxidantes/análisis , Antioxidantes/química , Valores de Referencia , Análisis de Varianza , Depuradores de Radicales Libres/análisis , beta Caroteno/análisis , FMN Reductasa/análisis , Cromatografía de Gases y Espectrometría de Masas
12.
An Acad Bras Cienc ; 90(1): 449-459, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29424393

RESUMEN

This study evaluated the chemical composition and antioxidant activity of fatty acids from the marine red algae Pterocladiella capillacea (S. G. Gmelin) Santelices & Hommersand 1997 and Osmundaria obtusiloba (C. Agardh) R. E. Norris 1991. The gas chromatography mass spectrometry (GC-MS) identified nine fatty acids in the two species. The major fatty acids of P. capillacea and O. obtusiloba were palmitic acid, oleic acid, arachidonic acid and eicosapentaenoic acid. The DPPH radical scavenging capacity of fatty acids was moderate ranging from 25.90% to 29.97%. Fatty acids from P. capillacea (31.18%) had a moderate ferrous ions chelating activity (FIC), while in O. obtusiloba (17.17%), was weak. The ferric reducing antioxidant power (FRAP) of fatty acids from P. capillacea and O. obtusiloba was low. As for ß-carotene bleaching (BCB), P. capillacea and O. obtusiloba showed a good activity. This is the first report of the antioxidant activities of fatty acids from the marine red algae P. capillacea and O. obtusiloba.


Asunto(s)
Antioxidantes/análisis , Antioxidantes/química , Ácidos Grasos/análisis , Ácidos Grasos/química , Rhodophyta/química , Análisis de Varianza , FMN Reductasa/análisis , Depuradores de Radicales Libres/análisis , Cromatografía de Gases y Espectrometría de Masas , Valores de Referencia , Factores de Tiempo , beta Caroteno/análisis
13.
J Ethnopharmacol ; 170: 158-66, 2015 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-25975514

RESUMEN

ETHNOPHARMACOLOGY RELEVANCE: In Colombia, more than 4.000 ophidian accidents occur per year and due to the scarce distribution and limited availability of antivenom, the use of traditional medicine has been perpetuated in some of its rural communities, in which initially, those affected are treated by healers and shamans using medicinal plants in different ways. METHODS: Research was conducted with renowned healers or connoisseurs of plants on the ethnobotany of ophidian accidents in five different areas and their municipalities of Antioquia: Magdalena Medio (Caracolí, Puerto Berrío); Bajo Cauca (Caucasia, Zaragoza); Nordeste (San Roque, Yalí); Norte (Gómez Plata, Valdivia); Suroeste (Ciudad Bolívar, Salgar); collecting information related to experience and time of use of plants in the treatment of these poisonings, amounts used, ways of use (beverage, bathing, ointment, chupaderas, vapors), preparation types (maceration or decoction) and treatment duration. RESULTS: 71 plant species were identified and collected, 49.29% of them without previous reports as antiophidian and 38.0% employed for the same purpose in other geographical areas. The leaves (24.82%), stems (11.68%) and flowers (10.95%) were found to be the most frequently employed structures in the preparation of the extracts, which are usually prepared by decoction (83.94%), maceration (6.57%). CONCLUSIONS: In this work, specimens lacking previous ethnobotanical reports have been found, plants used by ethnic groups from other regions of Antioquia and the world to treat snake bites; and herbaceous plants whose inhibitory activity of symptoms produced by some snake venoms, has been experimentally verified by in vivo and in vitro tests.


Asunto(s)
Antivenenos/uso terapéutico , Preparaciones de Plantas/uso terapéutico , Plantas Medicinales/química , Mordeduras de Serpientes/tratamiento farmacológico , Adulto , Anciano , Anciano de 80 o más Años , Antivenenos/aislamiento & purificación , Colombia , Etnofarmacología , Conocimientos, Actitudes y Práctica en Salud , Humanos , Medicina Tradicional , Persona de Mediana Edad , Fitoterapia/métodos , Preparaciones de Plantas/aislamiento & purificación
14.
J Ethnopharmacol ; 146(2): 449-55, 2013 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-23396114

RESUMEN

ETHNOPHARMACOLOGY RELEVANCE: Every year, over 4000 ophidian accidents take place in Colombia. The poor distribution and limited availability of antivenom have perpetuated the use of traditional medicine especially in rural communities. The medical care starts with the affected people receiving treatment by healers or shamans who use medicinal plants prepared in different ways. METHODS: This investigation was undertaken by conducting enquiries to the renowned healers or plants connoisseurs about the ethnobotany of the ophidian accident. In addition, this study included their experience and the time they have used plants in curing bites or stings by poisonous animals. Furthermore, it embraced the plant species used and the amount applied, the ways of their preparation (maceration or decoction), some application techniques (beverage, bathing, poultice, vapors), and duration of treatment. RESULTS: 29 species of plants were collected and identified. 82.7% of them were native, 27.5% had not been previously reported as antiophidian, and 38% had been employed for this purpose in other geographical areas. Leaves (43.59%) and stems (23.08%) were the components most frequently used in the medicinal preparation, which is usually done by maceration (51.92%) or decoction (25.00%). CONCLUSIONS: Throughout this study related to the treatment of snakebite accident, species have been found without any ethnobotanical reports. Moreover, plants being described as new specie and herbs such as Plantago major (Plantaginaceae) used in the treatment of snakebites by many ethnic groups have been found. In addition, herbaceous such as Renealmia alpinia (Zingiberaceae), whose antiophidian activity has been experimentally proven through in vivo and in vitro assays, have been discovered too.


Asunto(s)
Fitoterapia , Preparaciones de Plantas/uso terapéutico , Mordeduras de Serpientes/tratamiento farmacológico , Adulto , Anciano , Anciano de 80 o más Años , Colombia , Recolección de Datos , Etnobotánica , Humanos , Medicina Tradicional , Persona de Mediana Edad , Plantas Medicinales
16.
Lua Nova ; (69): 49-78, 2006. ilus
Artículo en Portugués | CidSaúde - Ciudades saludables | ID: cid-55529
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