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1.
Artículo en Inglés | MEDLINE | ID: mdl-39009933

RESUMEN

Glioblastoma (GBM) is the deadliest adult brain cancer. The current standard-of-care chemotherapy using orally administered temozolomide (TMZ) presents poor improvement in patient survival, emphasizing the compelling need for new therapies. A possible chemotherapeutic alternative is docetaxel (DTX), which possesses higher tumoricidal potency against GBM cells. However, its limited blood-brain barrier (BBB) permeability poses a constraint on its application. Nonetheless, nanomedicine offers promising avenues for overcoming this challenge. Angiopep-2 (ANG2) is a peptide that targets the BBB-overexpressed low-density lipoprotein receptor (LDLR). In this work, we managed, for the first time, to employ a pioneering approach of covalently linking zein protein with polyethylene glycol (PEG) and ANG2 prior to its formulation into nanoparticles (ZNPs) with enhanced stability and LDLR-mediated brain targetability, respectively. Carbodiimide and click chemistry approaches were optimized, resulting in functional modification of zein with around 25% PEG, followed by functional modification of PEG with nearly 100% ANG2. DTX-loaded ZNPs presented 100 nm average size, indicating high suitability for BBB crossing through receptor-mediated transcytosis. ZNPs maintained the cytotoxic effect of the loaded DTX against GBM cells, while demonstrating a safe matrix against BBB cells. Importantly, these brain-targeted ZNPs showcased up to fourfold enhancement in blood-to-brain permeability in a BBB in vitro model, highlighting the potential of this novel approach of BBB targeting in significantly improving therapeutic outcomes for GBM patients. The versatility of the system and the possibility of significantly increasing drug concentration in the brain open the door to its future application in a wide range of other brain-related diseases.

3.
Aliment Pharmacol Ther ; 59(1): 71-79, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-37833826

RESUMEN

BACKGROUND: Bone marrow transplantation (BMT) is a standard treatment for several haematologic conditions. Following BMT, patients may develop hepatobiliary complications that impact morbidity and mortality. The differential diagnosis may include drug-induced liver injury (DILI), sepsis-associated liver injury (SALI), sinusoidal obstruction syndrome (SOS), graft-versus-host disease (GVHD), viral hepatitis, ischaemic hepatitis, and fulminant hepatitis. AIMS: To evaluate the frequency, clinical characteristics, and outcomes of patients with hepatobiliary alterations associated with BMT in a tertiary referral centre. METHODS: This was a cross-sectional study with data collected from the medical records of patients undergoing BMT between January 2017 and June 2022. We diagnosed hepatobiliary complications based on established criteria. RESULTS: We included 377 patients; 55.7% had hepatobiliary complications. Female gender, pre-BMT hepatobiliary alteration, and haploidentical allogeneic transplantation were associated with increased risk with odds ratios (OR) of 1.8 (p = 0.005), 1.72 (p = 0.013) and 3.25 (p = 0.003), respectively. Patients with hepatobiliary complications spent longer in the hospital than those without (27.7 × 19.3 days, respectively; p < 0.001). Among 210 patients with hepatobiliary complications, 28 died compared to 5 of 167 without complications (OR 4.98; p = 0.001). CONCLUSIONS: Hepatobiliary complications are frequent in patients undergoing BMT. There is a greater risk of their occurrence in women, people with pre-BMT liver alterations, and in haploidentical transplants. The occurrence of these complications increases the length of stay and is associated with a higher risk of death.


Asunto(s)
Enfermedad Injerto contra Huésped , Hepatitis , Humanos , Femenino , Trasplante de Médula Ósea/efectos adversos , Estudios Transversales , Médula Ósea , Trasplante Homólogo/efectos adversos , Enfermedad Injerto contra Huésped/diagnóstico , Enfermedad Injerto contra Huésped/etiología , Hepatitis/complicaciones
4.
Oncotarget ; 14: 977-994, 2023 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-38085126

RESUMEN

Classic Hodgkin lymphoma (CHL), which accounts for 90-95% of all cases of Hodgkin lymphoma, is the most frequent cancer in adolescents and the most frequent lymphoma in adolescents and young adults. Despite progressive improvements over past decades and the general sensitivity of CHL to frontline chemotherapy, approximately 10-15% of patients have refractory disease that either does not respond to such therapy or progresses after an initial partial response. In patients with refractory or relapsed disease, standard treatment until recently consisted mainly of salvage chemotherapy, in many cases followed by high-dose chemotherapy and autologous stem-cell transplantation. However, improved understanding of the pathobiology of CHL, coupled with the introduction of novel agents, has markedly changed the treatment landscape in the past decade. Although refractory or relapsed CHL continues to be challenging, the therapeutic landscape is undergoing profound changes brought about by novel agents, particularly brentuximab vedotin and immunotherapy. In this review, we discuss the most salient treatment options for adult patients with refractory or relapsed CHL, with a special focus on the Brazilian healthcare setting, which is constrained by inherent characteristics of this system. In the attempt to balance efficacy, safety and tolerability, practicing physicians must rely on clinical trials and on results from real-world studies, and use their own point of view and experience, as well as patient characteristics and previous therapy, to make treatment decisions for refractory or relapsed CHL.


Asunto(s)
Trasplante de Células Madre Hematopoyéticas , Enfermedad de Hodgkin , Inmunoconjugados , Adolescente , Adulto Joven , Humanos , Enfermedad de Hodgkin/tratamiento farmacológico , Enfermedad de Hodgkin/patología , Brasil , Brentuximab Vedotina/uso terapéutico
5.
Sci Transl Med ; 15(687): eabo1930, 2023 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-36921032

RESUMEN

Autoimmune diseases are life-threatening disorders that cause increasing disability over time. Systemic lupus erythematosus (SLE) and other autoimmune diseases arise when immune stimuli override mechanisms of self-tolerance. Accumulating evidence has demonstrated that protein glycosylation is substantially altered in autoimmune disease development, but the mechanisms by which glycans trigger these autoreactive immune responses are still largely unclear. In this study, we found that presence of microbial-associated mannose structures at the surface of the kidney triggers the recognition of DC-SIGN-expressing γδ T cells, inducing a pathogenic interleukin-17a (IL-17a)-mediated autoimmune response. Mice lacking Mgat5, which have a higher abundance of mannose structures in the kidney, displayed increased γδ T cell infiltration into the kidney that was associated with spontaneous development of lupus in older mice. N-acetylglucosamine supplementation, which promoted biosynthesis of tolerogenic branched N-glycans in the kidney, was found to inhibit γδ T cell infiltration and control disease development. Together, this work reveals a mannose-γδ T cell-IL-17a axis in SLE immunopathogenesis and highlights glycometabolic reprogramming as a therapeutic strategy for autoimmune disease treatment.


Asunto(s)
Enfermedades Autoinmunes , Lupus Eritematoso Sistémico , Animales , Ratones , Autoinmunidad , Manosa , Interleucina-17/metabolismo , Receptores de Antígenos de Linfocitos T gamma-delta/metabolismo
6.
Small ; 19(22): e2300029, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36852650

RESUMEN

Minimal therapeutic advances have been achieved over the past two decades for glioblastoma (GBM), which remains an unmet clinical need. Here, hypothesis-driven stimuli-responsive nanoparticles (NPs) for docetaxel (DTX) delivery to GBM are reported, with multifunctional features that circumvent insufficient blood-brain barrier (BBB) trafficking and lack of GBM targeting-two major hurdles for anti-GBM therapies. NPs are dual-surface tailored with a i) brain-targeted acid-responsive Angiopep-2 moiety that triggers NP structural rearrangement within BBB endosomal vesicles, and ii) L-Histidine moiety that provides NP preferential accumulation into GBM cells post-BBB crossing. In tumor invasive margin patient cells, the stimuli-responsive multifunctional NPs target GBM cells, enhance cell uptake by 12-fold, and induce three times higher cytotoxicity in 2D and 3D cell models. Moreover, the in vitro BBB permeability is increased by threefold. A biodistribution in vivo trial confirms a threefold enhancement of NP accumulation into the brain. Last, the in vivo antitumor efficacy is validated in GBM orthotopic models following intratumoral and intravenous administration. Median survival and number of long-term survivors are increased by 50%. Altogether, a preclinical proof of concept supports these stimuli-responsive multifunctional NPs as an effective anti-GBM multistage chemotherapeutic strategy, with ability to respond to multiple fronts of the GBM microenvironment.


Asunto(s)
Neoplasias Encefálicas , Glioblastoma , Nanopartículas , Humanos , Glioblastoma/tratamiento farmacológico , Glioblastoma/patología , Nanomedicina , Distribución Tisular , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/patología , Encéfalo , Barrera Hematoencefálica/patología , Sistemas de Liberación de Medicamentos , Nanopartículas/química , Línea Celular Tumoral , Microambiente Tumoral
7.
J Control Release ; 353: 77-95, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36410614

RESUMEN

Despite being the most prevalent and lethal type of adult brain cancer, glioblastoma (GBM) remains intractable. Promising anti-GBM nanoparticle (NP) systems have been developed to improve the anti-cancer performance of difficult-to-deliver therapeutics, with particular emphasis on tumor targeting strategies. However, current disease modeling toolboxes lack close-to-native in vitro models that emulate GBM microenvironment and bioarchitecture, thus partially hindering translation due to poorly predicted clinical responses. Herein, human GBM heterotypic multicellular tumor microtissues (MCTMs) are generated through high-throughput 3D modeling of U-251 MG tumor cells, tissue differentiated macrophages isolated from peripheral monocytes, and brain microvascular primary endothelial cells. GBM MCTMs mimicked tumor spatial organization, extracellular matrix production and necrosis areas. The bioactivity of a model drug, docetaxel (DTX), and of tumor-targeted DTX-loaded polymeric NPs with a surface L-Histidine moiety (H-NPs), were assessed in the MCTMs. MCTMs cell uptake and anti-proliferative effect was 8- and 3-times higher for H-NPs, respectively, compared to the non-targeted NPs and to free DTX. H-NPs provided a decrease of MCTMs anti-inflammatory M2-macrophages, while increasing their pro-inflammatory M1 counterparts. Moreover, H-NPs showed a particular biomolecular signature through reduced secretion of an array of medium cytokines (IFN-γ, IL-1ß, IL-1Ra, IL-6, IL-8, TGF-ß). Overall, MCTMs provide an in vitro biomimetic model to recapitulate key cellular and structural features of GBM and improve in vivo drug response predictability, fostering future clinical translation of anti-GBM nano-therapeutic strategies.


Asunto(s)
Neoplasias Encefálicas , Glioblastoma , Humanos , Glioblastoma/tratamiento farmacológico , Glioblastoma/patología , Células Endoteliales , Línea Celular Tumoral , Docetaxel/farmacología , Docetaxel/uso terapéutico , Citocinas , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/patología , Microambiente Tumoral
8.
Bone Marrow Transplant ; 57(3): 453-459, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35027676

RESUMEN

In the COVID-19 scenario, patients undergoing hematopoietic stem cell transplantation (HSCT) infected with SARS-CoV-2 may have an increased risk of death. Through a national multicenter study, we aimed to describe the impact of COVID-19 on the survival of HSCT recipients in Brazil. Eighty-six patients with a confirmed diagnosis of SARS-CoV-2 (92% by RT-PCR) were included. There were 24 children and 62 adults receiving an autologous (n = 25) and allogeneic (n = 61) HSCT for malignant (n = 72) and non-malignant (n = 14) disorders. Twenty-six patients died, (10 on autologous (38%) and 16 patients (62%) on allogeneic group). The estimated overall survival (OS) at day 40 was 69%. Adults had decreased OS compared to children (66% vs 79%, p = 0.03). The severity of symptoms at the time of diagnosis, ECOG score, laboratory tests (C-reactive protein, urea values) were higher in patients who died (p < 0.05). In conclusion, HSCT recipients infected with SARS-CoV-2 have a high mortality rate mainly in adults and patients with critical initial COVID-19 presentation. These findings show the fragility of HSCT recipients with SARS-CoV-2 infection. Therefore, the importance of adherence to preventive measures is evident, in addition to prioritizing the vaccination of family members and the HSCT team.


Asunto(s)
COVID-19 , Trasplante de Células Madre Hematopoyéticas , Adulto , Brasil/epidemiología , COVID-19/complicaciones , Niño , Humanos , SARS-CoV-2 , Tasa de Supervivencia
9.
Biomater Sci ; 9(19): 6510-6527, 2021 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-34582531

RESUMEN

Healing of intestinal chronic wounds remains a major challenge as current therapies are ineffective in promoting proper regeneration of the damaged intestinal wall. An innovative concept, based on a bioinspired multifunctional alginate-melanin hybrid 3D scaffold, to target both inflammatory and regenerative processes, is proposed herein. Hydrogel-entrapped melanin nanoparticles demonstrated free-radical scavenging activity, supported by the neutralization of free-radicals in solution (90%), and the in vitro capture of reactive oxygen species (ROS) produced by stimulated macrophages in an inflammatory-mimicking environment. Notably, scaffolds could be reused (at least 3 times), while maintaining these properties. The extracellular matrix (ECM)-inspired biomaterial, containing protease-sensitive and integrin-binding domains, exhibited remarkable ability for cell colonisation. Human intestinal fibroblasts and epithelial cells (Caco-2) co-seeded on lyophilized scaffolds were able to invade/colonize the construct and produce endogenous ECM, key for neo-tissue formation and re-epithelialization. Scaffolds presented tuneable mechanical properties and could be used both in hydrated and freeze-dried states, maintaining their performance upon rehydration, which are attractive features for clinical application. Collectively, our results highlight the potential of biofunctionalized alginate-melanin hybrid 3D scaffolds as multi-therapeutic patches for modulating inflammation and tissue regeneration in chronic intestinal wounds, which address a major but still unmet clinical need. The proposed multi-therapeutic strategy may potentially be extended to the treatment of other chronic wounds.


Asunto(s)
Hidrogeles , Andamios del Tejido , Células CACO-2 , Matriz Extracelular , Humanos , Inflamación/tratamiento farmacológico
10.
Nanomedicine (Lond) ; 15(23): 2287-2309, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32945230

RESUMEN

Therapeutic and diagnostic payloads are usually associated with properties that compromise their efficacy, such as poor aqueous solubility, short half-life, low bioavailability, nonspecific accumulation and diverse side effects. Nanotechnological solutions have emerged to circumvent some of these drawbacks, augmenting therapeutic and/or diagnostic outcomes. Nanotechnology has benefited from the rise in polymer science research for the development of novel nanosystems for therapeutic and diagnostic purposes. Polymers are a widely used class of biomaterials, with a considerable number of regulatory approvals for application in clinics. In addition to their versatility in production and functionalization, several synthetic and natural polymers demonstrate biocompatible properties that dictate their successful biological performance. This article highlights the physicochemical characteristics of a variety of natural and synthetic biocompatible polymers, as well as their role in the manufacture of nanotechnology-based systems, state-of-art applications in disease treatment and diagnosis, and current challenges in finding a way to clinics.


Asunto(s)
Sistemas de Liberación de Medicamentos , Polímeros , Materiales Biocompatibles , Nanotecnología , Solubilidad
11.
Mater Sci Eng C Mater Biol Appl ; 112: 110920, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32409071

RESUMEN

Chitosan was grafted with O-methyl-O'-succinylpolyethylene glycol and oleic acid after a two-step carbodiimide coupling. The structural and physicochemical characterization of the compounds confirmed the successful conjugation of the hydrophilic and hydrophobic moieties to the chitosan backbone. The amphiphilic chitosan derivative obtained allowed the formation of polymeric micelles with an average size of 140 nm, a polydispersity index <0.234, and a positive superficial charge. Camptothecin, used as a model hydrophobic drug, was successfully carried into the polymeric micelles with an encapsulation efficiency of 78%. The in vitro drug release was evaluated in simulated gastrointestinal fluids, exhibiting a low release of camptothecin in gastric media and a controlled release in intestinal fluids. Furthermore, it was demonstrated that chitosan micelles were able to stabilize camptothecin, protecting up to 75% of the drug from hydrolysis, preserving its active lactone form. This new chitosan amphiphilic system exhibits great potential to load hydrophobic drugs, acting as a promising delivery system.


Asunto(s)
Antineoplásicos/química , Quitosano/química , Portadores de Fármacos/química , Micelas , Antineoplásicos/metabolismo , Camptotecina/química , Camptotecina/metabolismo , Liberación de Fármacos , Ácido Gástrico/química , Interacciones Hidrofóbicas e Hidrofílicas , Cinética , Ácido Oléico/química , Tamaño de la Partícula , Polietilenglicoles/química , Termodinámica
12.
Molecules ; 25(4)2020 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-32098281

RESUMEN

Glycosaminoglycans (GAG) are long, linear polysaccharides that display a wide range of relevant biological roles. Particularly, in the extracellular matrix (ECM) GAG specifically interact with other biological molecules, such as growth factors, protecting them from proteolysis or inhibiting factors. Additionally, ECM GAG are partially responsible for the mechanical stability of tissues due to their capacity to retain high amounts of water, enabling hydration of the ECM and rendering it resistant to compressive forces. In this review, the use of GAG for developing hydrogel networks with improved biological activity and/or mechanical properties is discussed. Greater focus is given to strategies involving the production of hydrogels that are composed of GAG alone or in combination with other materials. Additionally, approaches used to introduce GAG-inspired features in biomaterials of different sources will also be presented.


Asunto(s)
Glicosaminoglicanos/química , Hidrogeles/química , Polisacáridos/química , Matriz Extracelular/química , Matriz Extracelular/efectos de los fármacos , Glicosaminoglicanos/uso terapéutico , Humanos , Hidrogeles/síntesis química , Hidrogeles/uso terapéutico , Péptidos y Proteínas de Señalización Intercelular/química , Polisacáridos/uso terapéutico , Proteolisis/efectos de los fármacos , Agua/química
13.
J Mater Chem B ; 8(4): 813-825, 2020 01 28.
Artículo en Inglés | MEDLINE | ID: mdl-31909410

RESUMEN

A novel blue-emitting fluorescent alginate derivative has been successfully synthesised in a simple two-reaction step procedure, using an aqueous conjugation strategy that involved carbodiimide coupling followed by an alkyne-azide "click" reaction. The modified alginate maintained the characteristic ability to form mechanically stable hydrogels by ionic crosslinking. The fluorescent properties of the developed biomaterial were investigated both in solution and hydrogel states, revealing that grafting of the coumarin fluorophore to alginate greatly enhanced its fluorescent properties. Importantly, hydrogels maintained around 80% of their initial fluorescence upon long periods of incubation under physiologic conditions. The fluorescent alginate hydrogels showed to be biocompatible in vitro, supporting the viability, metabolic activity and proliferation of mammary epithelial cells and, more importantly, their morphogenesis into spheroids and polarized acini-like structures. These hydrogels were further applied in the establishment of cell-in-gel microarrays for high-throughput screening of cell behaviour in three-dimensional (3D) matrices, being essential for spotting optimization and analysis. Collectively, our results highlight the potential of coumarin-grafted blue-emitting fluorescent alginate as a valuable tool for biomedical applications where hydrogel tracing is required.


Asunto(s)
Alginatos/química , Materiales Biocompatibles/química , Cumarinas/química , Colorantes Fluorescentes/química , Análisis de Matrices Tisulares , Alginatos/síntesis química , Animales , Materiales Biocompatibles/síntesis química , Células Cultivadas , Células Epiteliales/química , Células Epiteliales/metabolismo , Técnica del Anticuerpo Fluorescente , Colorantes Fluorescentes/síntesis química , Ensayos Analíticos de Alto Rendimiento , Hidrogeles/síntesis química , Hidrogeles/química , Ensayo de Materiales , Ratones , Estructura Molecular
14.
Int J Mol Sci ; 20(22)2019 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-31739392

RESUMEN

Biopolymers derived from polysaccharides are a sustainable and environmentally friendly alternative to the synthetic counterparts available in the market. Due to their distinctive properties, the cyanobacterial extracellular polymeric substances (EPS), mainly composed of heteropolysaccharides, emerge as a valid alternative to address several biotechnological and biomedical challenges. Nevertheless, biotechnological/biomedical applications based on cyanobacterial EPS have only recently started to emerge. For the successful exploitation of cyanobacterial EPS, it is important to strategically design the polymers, either by genetic engineering of the producing strains or by chemical modification of the polymers. This requires a better understanding of the EPS biosynthetic pathways and their relationship with central metabolism, as well as to exploit the available polymer functionalization chemistries. Considering all this, we provide an overview of the characteristics and biological activities of cyanobacterial EPS, discuss the challenges and opportunities to improve the amount and/or characteristics of the polymers, and report the most relevant advances on the use of cyanobacterial EPS as scaffolds, coatings, and vehicles for drug delivery.


Asunto(s)
Materiales Biocompatibles/química , Biopolímeros/química , Cianobacterias/química , Matriz Extracelular de Sustancias Poliméricas/química , Materiales Biocompatibles/aislamiento & purificación , Bioingeniería , Biopolímeros/aislamiento & purificación , Cianobacterias/metabolismo , Matriz Extracelular de Sustancias Poliméricas/metabolismo , Redes y Vías Metabólicas , Estructura Molecular
15.
J Fluoresc ; 29(5): 1171-1181, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31493174

RESUMEN

Glutaraldehyde (GTA) is a dialdehyde used as biological fixative and its interaction with proteins like bovine serum albumin (BSA) has been well described. Additionally, GTA is known to induce fluorescence when interacting with BSA molecules. In this work, it is developed a new sensitive and reproducible method for BSA quantification using GTA crosslinking to endow fluorescence to BSA molecules. This method can be used with standard lab equipment, providing a low cost, fast-tracking and straightforward approach for BSA quantification. Techniques such as confocal laser scanning microscopy (CLSM) and spectrofluorometry are applied for quantitative assessment, and widefield fluorescence microscopy for qualitative assessment. Qualitative and quantitative correlations between BSA content and GTA-induced fluorescence are verified. BSA concentrations as low as 62.5 µg/mL are detected using CLSM. This method can be highly advantageous for protein quantification in three-dimensional hydrogel systems, specially to evaluate protein loading/release in protein delivery or molecular imprinting systems. Graphical Abstract Preparation and analysis of glutaraldehyde-induced protein-fluorescence in 3D hydrogels. Alginate-methacrylate hydrogels containing varying amounts of bovine serum albumin (BSA) are prepared by photopolymerization and then incubated in glutaraldehyde solutions. Samples observation is performed using confocal laser scanning microscopy, spectrofluorometry and widefield fluorescence microscopy. Data is processed and retrieves a quantitative correlation between protein content and fluorescence levels.


Asunto(s)
Fluorescencia , Colorantes Fluorescentes/química , Glutaral/química , Albúmina Sérica Bovina/análisis , Animales , Bovinos , Colorantes Fluorescentes/síntesis química , Glutaral/síntesis química , Hidrogeles/síntesis química , Hidrogeles/química , Tamaño de la Partícula
16.
Environ Int ; 125: 567-578, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30683322

RESUMEN

BACKGROUND: The World Health Organization (WHO) and the International Labour Organization (ILO) are developing a joint methodology for estimating the national and global work-related burden of disease and injury (WHO/ILO joint methodology), with contributions from a large network of experts. In this paper, we present the protocol for two systematic reviews of parameters for estimating the number of deaths and disability-adjusted life years from cardiovascular disease attributable to exposure to occupational noise, to inform the development of the WHO/ILO joint methodology. OBJECTIVES: We aim to systematically review studies on exposure to occupational noise (Systematic Review 1) and systematically review and meta-analyse estimates of the effect of occupational noise on cardiovascular diseases (Systematic Review 2), applying the Navigation Guide systematic review methodology as an organizing framework, conducting both systematic reviews in tandem and in a harmonized way. DATA SOURCES: Separately for Systematic Reviews 1 and 2, we will search electronic academic databases for potentially relevant records from published and unpublished studies, including Medline, EMBASE, Web of Science and CISDOC. We will also search electronic grey literature databases, Internet search engines and organizational websites; hand search reference list of previous systematic reviews and included study records; and consult additional experts. STUDY ELIGIBILITY AND CRITERIA: We will include working-age (≥15 years) workers in the formal and informal economy in any WHO and/or ILO Member State, but exclude children (<15 years) and unpaid domestic workers. The eligible risk factor will be occupational noise. Eligible outcomes will be hypertensive heart disease, ischaemic heart disease, stroke, cardiomyopathy, myocarditis, endocarditis and other circulatory diseases. For Systematic Review 1, we will include quantitative prevalence studies of exposure to occupational noise (i.e., low: <85 dB(A) and high: ≥85 dB(A)) stratified by country, sex, age and industrial sector or occupation. For Systematic Review 2, we will include randomized controlled trials, cohort studies, case-control studies and other non-randomized intervention studies with an estimate of the relative effect of high exposure to occupational noise on the prevalence of, incidence of or mortality due to cardiovascular disease, compared with the theoretical minimum risk exposure level (i.e., low exposure). STUDY APPRAISAL AND SYNTHESIS METHODS: At least two review authors will independently screen titles and abstracts against the eligibility criteria at a first stage and full texts of potentially eligible records at a second stage, followed by extraction of data from qualifying studies. At least two review authors will assess risk of bias and the quality of evidence, using the most suited tools currently available. For Systematic Review 2, if feasible, we will combine relative risks using meta-analysis. We will report results using the guidelines for accurate and transparent health estimates reporting (GATHER) for Systematic Review 1 and the preferred reporting items for systematic reviews and meta-analyses guidelines (PRISMA) for Systematic Review 2. PROSPERO registration number: CRD42018092272.


Asunto(s)
Enfermedades Cardiovasculares/etiología , Metaanálisis como Asunto , Ruido en el Ambiente de Trabajo/efectos adversos , Enfermedades Profesionales/etiología , Exposición Profesional/análisis , Revisiones Sistemáticas como Asunto , Costo de Enfermedad , Estudios Transversales , Humanos , Organización Mundial de la Salud
18.
Molecules ; 21(6)2016 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-27338313

RESUMEN

A heterogeneous supramolecular catalytic system for multicomponent aldol-'click' reactions is reported. The copper(I) metallohydrogel functionalized with a phenyltriazole fragment was able to catalyze the multicomponent reaction between phenylacetylene, p-nitrobenzaldehyde, and an azide containing a ketone moiety, obtaining the corresponding aldol products in good yields. A possible mechanistic pathway responsible for this unexpected catalytic behavior has been proposed.


Asunto(s)
Química Clic , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Cetonas/química , Acetileno/análogos & derivados , Acetileno/química , Aldehídos/química , Azidas/química , Benzaldehídos/química , Catálisis , Cobre/química , Metales/química , Estructura Molecular , Estereoisomerismo
19.
Chemistry ; 22(25): 8676-84, 2016 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-27168408

RESUMEN

The catalytic performance of triazolyl-based molecular gels was investigated in the Huisgen 1,3-dipolar cycloaddition of alkynes and azides. Low-molecular-weight gelators derived from l-valine were synthesized and functionalized with a triazole fragment. The resultant compounds formed gels either with or without copper, in a variety of solvents of different polarity. The gelators coordinated Cu(I) and exhibited a high catalytic activity in the gel phase for the model reaction between phenylacetylene and benzylazide. Additionally, the gels were able to participate in autocatalytic synthesis and the influence of small structural changes on their performance was observed.

20.
Materials (Basel) ; 9(4)2016 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-28773350

RESUMEN

Three new silica-based glass formulations with low molar Ca/P ratio (2-3) have been synthesized. The thermal properties, the crystalline phases induced by thermal treatments and the sintering ability of each glass formulation have been investigated by simultaneous differential scanning calorimetry-thermogravimetric analysis (DSC-TG), X-ray diffraction (XRD) and hot stage microscopy (HSM). The glasses exhibited a good sintering behavior, with two samples achieving shrinkage of 85%-95% prior to crystallization. The bioactivity of the glasses in simulated body fluid (SBF) has been investigated by performing XRD and Fourier transform infrared spectroscopy (FTIR) on the samples prior and after immersion. The glasses with lower MgO contents were able to form a fully crystallized apatite layer after three days of immersion in simulated body fluid (SBF), while for the glass exhibiting a higher MgO content in its composition, the crystallization of the Ca-P layer was achieved after seven days. The conjugation of these properties opens new insights on the synthesis of highly bioactive and mechanically strong prosthetic materials.

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