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1.
Cell Rep Methods ; 3(11): 100624, 2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-37909050

RESUMO

Amphitropic proteins and peptides reversibly partition from solution to membrane, a key process that regulates their functions. Experimental approaches classically used to measure protein partitioning into lipid bilayers, such as fluorescence and circular dichroism, are hardly usable when the peptides or proteins do not exhibit significant polarity and/or conformational changes upon membrane binding. Here, we describe binding to lipid vesicles (B2LiVe), a simple, robust, and widely applicable nuclear magnetic resonance (NMR) method to determine the solution-to-membrane partitioning of unlabeled proteins or peptides. B2LiVe relies on previously described proton 1D-NMR fast-pulsing techniques. Membrane partitioning induces a large line broadening, leading to a loss of protein signals; therefore, the decrease of the NMR signal directly measures the fraction of membrane-bound protein. The method uses low polypeptide concentrations and has been validated on several membrane-interacting polypeptides, ranging from 3 to 54 kDa, with membrane vesicles of different sizes and various lipid compositions.


Assuntos
Bicamadas Lipídicas , Peptídeos , Peptídeos/química , Bicamadas Lipídicas/química , Espectroscopia de Ressonância Magnética , Proteínas de Membrana , Imageamento por Ressonância Magnética
2.
Polymers (Basel) ; 15(7)2023 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-37050275

RESUMO

The globalization of the market, as well as the increasing world population, which require a higher demand for food products, pose a great challenge to ensure food safety and prevent food loss and waste. In this sense, active materials with antibacterial properties are an important alternative in the prolongation of shelf life and ensuring food safety. In this work, the ability of copper(II) hydroxy nitrate (CuHS) to obtain antibacterial films based on low density polyethylene (LDPE) and polylactic acid (PLA), was evaluated. The thermal properties of the composites, evaluated using thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC), showed that the concentrations of added CuHS do not particularly change these characteristics with respect to the neat polymer matrix films. The mechanical properties, determined using dynamic mechanical analysis (DMTA), indicate a small increase in the brittleness of the material in PLA-based composites. The antibacterial properties against Listeria monocytogenes and Salmonella enterica were evaluated using a surface contact test, and a bacterial reduction of at least 8 to 9 logarithmic units for the composites with 0.3% CuHS, both in LDPE and PLA and against both bacteria, were achieved. The reusability of the composite films after their first use demonstrated a higher stability against Listeria monocytogenes. The migration and cytotoxicity of the composites loaded with 0.3% CuHS was evaluated, demonstrating the safety of these materials, which reinforces their potential use in food packaging applications.

3.
J Fungi (Basel) ; 9(2)2023 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-36836270

RESUMO

Earlier studies have shown that the outer layers of the conidial and mycelial cell walls of Aspergillus fumigatus are different. In this work, we analyzed the polysaccharidome of the resting conidial cell wall and observed major differences within the mycelium cell wall. Mainly, the conidia cell wall was characterized by (i) a smaller amount of α-(1,3)-glucan and chitin; (ii) a larger amount of ß-(1,3)-glucan, which was divided into alkali-insoluble and water-soluble fractions, and (iii) the existence of a specific mannan with side chains containing galactopyranose, glucose, and N-acetylglucosamine residues. An analysis of A. fumigatus cell wall gene mutants suggested that members of the fungal GH-72 transglycosylase family play a crucial role in the conidia cell wall ß-(1,3)-glucan organization and that α-(1,6)-mannosyltransferases of GT-32 and GT-62 families are essential to the polymerization of the conidium-associated cell wall mannan. This specific mannan and the well-known galactomannan follow two independent biosynthetic pathways.

4.
Proc Natl Acad Sci U S A ; 120(6): e2212003120, 2023 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-36719915

RESUMO

While establishing an invasive infection, the dormant conidia of Aspergillus fumigatus transit through swollen and germinating stages, to form hyphae. During this morphotype transition, the conidial cell wall undergoes dynamic remodeling, which poses challenges to the host immune system and antifungal drugs. However, such cell wall reorganization during conidial germination has not been studied so far. Here, we explored the molecular rearrangement of Aspergillus fumigatus cell wall polysaccharides during different stages of germination. We took advantage of magic-angle spinning NMR to investigate the cell wall polysaccharides, without employing any destructive method for sample preparation. The breaking of dormancy was associated with a significant change in the molar ratio between the major polysaccharides ß-1,3-glucan and α-1,3-glucan, while chitin remained equally abundant. The use of various polarization transfers allowed the detection of rigid and mobile polysaccharides; the appearance of mobile galactosaminogalactan was a molecular hallmark of germinating conidia. We also report for the first time highly abundant triglyceride lipids in the mobile matrix of conidial cell walls. Water to polysaccharides polarization transfers revealed an increased surface exposure of glucans during germination, while chitin remained embedded deeper in the cell wall, suggesting a molecular compensation mechanism to keep the cell wall rigidity. We complement the NMR analysis with confocal and atomic force microscopies to explore the role of melanin and RodA hydrophobin on the dormant conidial surface. Exemplified here using Aspergillus fumigatus as a model, our approach provides a powerful tool to decipher the molecular remodeling of fungal cell walls during their morphotype switching.


Assuntos
Aspergillus fumigatus , Proteínas Fúngicas , Aspergillus fumigatus/metabolismo , Esporos Fúngicos/metabolismo , Proteínas Fúngicas/metabolismo , Polissacarídeos/metabolismo , Quitina/metabolismo , Glucanos/metabolismo , Parede Celular/metabolismo
5.
J Gen Intern Med ; 38(7): 1655-1663, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36717430

RESUMO

BACKGROUND: Inappropriate hospital admissions compromise the efficiency of the health care system. This work analyzes, for the first time, the prevalence of inappropriate admission and its association with clinical and epidemiological patient characteristics. OBJECTIVES: To estimate the prevalence, associated risk factors, and economic impact of inappropriate hospital admissions. DESIGN AND PARTICIPANTS: This was a cross-sectional observational study of all hospitalized patients in a high complexity hospital of over 901 beds capacity in Spain. The prevalence of inappropriate admission and its causes, the association of inappropriateness with patients' intrinsic risk factors (IRFs), and associated financial costs were analyzed with the Appropriateness Evaluation Protocol in a multivariate model. MAIN MEASURES AND KEY RESULTS: A total of 593 patients were analyzed, and a prevalence of inappropriate admissions of 11.9% (95% CI: 9.5 to 14.9) was found. The highest number of IRFs for developing health care-related complications was associated with inappropriateness, which was more common among patients with 1 IRF (OR [95% CI]: 9.68 [3.6 to 26.2.] versus absence of IRFs) and among those with surgical admissions (OR [95% CI]: 1.89 [1.1 to 3.3] versus medical admissions). The prognosis of terminal disease reduced the risk (OR [95% CI]: 0.28 [0.1 to 0.9] versus a prognosis of full recovery based on baseline condition). Inappropriate admissions were responsible for 559 days of avoidable hospitalization, equivalent to €17,604.6 daily and €139,076.4 in total, mostly attributable to inappropriate emergency admissions (€96,805.3). CONCLUSIONS: The prevalence of inappropriate admissions is similar to the incidence found in previous studies and is a useful indicator in monitoring this kind of overuse. Patients with a moderate number of comorbidities were subject to a higher level of inappropriateness. Inappropriate admission had a substantial and avoidable financial impact.


Assuntos
Hospitalização , Hospitais , Humanos , Tempo de Internação , Estudos Transversais , Custos e Análise de Custo , Admissão do Paciente
6.
J Mol Biol ; 435(3): 167929, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36566799

RESUMO

We have previously shown that the CBb subunit of crotoxin, a ß-neurotoxin with phospholipase A2 (PLA2) activity, targets the human ΔF508CFTR chloride channel implicated in cystic fibrosis (CF). By direct binding to the nucleotide binding domain 1 (NBD1) of ΔF508CFTR, this neurotoxic PLA2 acts as a potentiator increasing chloride channel current and corrects the trafficking defect of misfolded ΔF508CFTR inside the cell. Here, for a therapeutics development of new anti-cystic fibrosis agents, we use a structure-based in silico approach to design peptides mimicking the CBb-ΔF508NBD1 interface. Combining biophysical and electrophysiological methods, we identify several peptides that interact with the ΔF508NBD1 domain and reveal their effects as potentiators on phosphorylated ΔF508CFTR. Moreover, protein-peptide interactions and electrophysiological studies allowed us to identify key residues of ΔF508NBD1 governing the interactions with the novel potentiators. The designed peptides bind to the same region as CBb phospholipase A2 on ΔF508NBD1 and potentiate chloride channel activity. Certain peptides also show an additive effect towards the clinically approved VX-770 potentiator. The identified CF therapeutics peptides represent a novel class of CFTR potentiators and illustrate a strategy leading to reproducing the effect of specific protein-protein interactions.


Assuntos
Crotoxina , Regulador de Condutância Transmembrana em Fibrose Cística , Peptídeos , Humanos , Crotoxina/química , Crotoxina/farmacologia , Fibrose Cística , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Mutação , Peptídeos/química , Fosfolipases/metabolismo , Fosfolipases A2/metabolismo
8.
BMC Biol ; 20(1): 176, 2022 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-35945584

RESUMO

BACKGROUND: Calmodulin (CaM) is an evolutionarily conserved eukaryotic multifunctional protein that functions as the major sensor of intracellular calcium signaling. Its calcium-modulated function regulates the activity of numerous effector proteins involved in a variety of physiological processes in diverse organs, from proliferation and apoptosis, to memory and immune responses. Due to the pleiotropic roles of CaM in normal and pathological cell functions, CaM antagonists are needed for fundamental studies as well as for potential therapeutic applications. Calmidazolium (CDZ) is a potent small molecule antagonist of CaM and one the most widely used inhibitors of CaM in cell biology. Yet, CDZ, as all other CaM antagonists described thus far, also affects additional cellular targets and its lack of selectivity hinders its application for dissecting calcium/CaM signaling. A better understanding of CaM:CDZ interaction is key to design analogs with improved selectivity. Here, we report a molecular characterization of CaM:CDZ complexes using an integrative structural biology approach combining SEC-SAXS, X-ray crystallography, HDX-MS, and NMR. RESULTS: We provide evidence that binding of a single molecule of CDZ induces an open-to-closed conformational reorientation of the two domains of CaM and results in a strong stabilization of its structural elements associated with a reduction of protein dynamics over a large time range. These CDZ-triggered CaM changes mimic those induced by CaM-binding peptides derived from physiological protein targets, despite their distinct chemical natures. CaM residues in close contact with CDZ and involved in the stabilization of the CaM:CDZ complex have been identified. CONCLUSION: Our results provide molecular insights into CDZ-induced dynamics and structural changes of CaM leading to its inhibition and open the way to the rational design of more selective CaM antagonists. Calmidazolium is a potent and widely used inhibitor of calmodulin, a major mediator of calcium-signaling in eukaryotic cells. Structural characterization of calmidazolium-binding to calmodulin reveals that it triggers open-to-closed conformational changes similar to those induced by calmodulin-binding peptides derived from enzyme targets. These results provide molecular insights into CDZ-induced dynamics and structural changes of CaM leading to its inhibition and open the way to the rational design of more selective CaM antagonists.


Assuntos
Cálcio , Calmodulina , Cálcio/metabolismo , Calmodulina/química , Calmodulina/metabolismo , Imidazóis , Ligação Proteica , Espalhamento a Baixo Ângulo , Difração de Raios X
9.
Eur J Clin Invest ; : e13851, 2022 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-35909351

RESUMO

INTRODUCTION: Adverse Events (AE) are one of the main problems in healthcare. Therefore, many policies have been developed worldwide to mitigate their impact. The Patient Safety Incident Study in Hospitals in the Community of Madrid (ESHMAD) measures the results of them in the region. METHODS: Cross-sectional study, conducted in May 2019, in hospitalised patients in 34 public hospitals using the Harvard Medical Practice Study methodology. A logistic regression model was carried out to study the association of the variables with the presence of AE, calibrated and adjusted by patient. RESULTS: A total of 9,975 patients were included, estimating a prevalence of AE of 11.9%. A higher risk of AE was observed in patients with surgical procedures (OR[CI95%]: 2.15[1.79 to 2.57], vs. absence), in Intensive Care Units (OR[CI95%]: 1.60[1.17 to 2.17], vs. Medical), and in hospitals of medium complexity (OR[CI95%]: 1.45[1.12 to 1.87], vs. low complexity). A 62.6% of AE increased the length of the stay or it was the cause of admission, and 46.9% of AE were considered preventable. In 11.5% of patients with AE, they had contributed to their death. CONCLUSIONS: The prevalence of AE remains similar to the previously estimated in studies developed with the same methodology. AE keep leading to longer hospital stays, contributing to patient's death, showing that it is necessary to put focus on patient safety again. A detailed analysis of these events has enabled the detection of specific areas for improvement according to the type of care, centre, and patient.

10.
ACS Chem Biol ; 17(6): 1415-1426, 2022 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-35649238

RESUMO

Epigenetics has received much attention in the past decade. Many insights on epigenetic (dys)regulation in diseases have been obtained, and clinical therapies targeting them are in place. However, the readers of the epigenetic marks are lacking enlightenment behind this revolution, and it is poorly understood how DNA methylation is being read and translated to chromatin function and cellular responses. Chemical probes targeting the methyl-CpG readers, such as the methyl-CpG binding domain proteins (MBDs), could be used to study this mechanism. We have designed analogues of 5-methylcytosine to probe the MBD domain of human MBD2. By setting up a protein thermal shift assay and an AlphaScreen-based test, we were able to identify three fragments that bind MBD2 alone and disrupt the MBD2-methylated DNA interactions. Two-dimensional NMR experiments and virtual docking gave valuable insights into the interaction of the ligands with the protein showing that the compounds interact with residues that are important for DNA recognition. These constitute the starting point for the design of potent chemical probes for MBD proteins.


Assuntos
Metilação de DNA , Proteínas de Ligação a DNA , 5-Metilcitosina/metabolismo , Ilhas de CpG , DNA/química , Proteínas de Ligação a DNA/metabolismo , Humanos
11.
Front Immunol ; 12: 749074, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34867977

RESUMO

In this study, the human immune response mechanisms against Sporothrix brasiliensis and Sporothrix schenckii, two causative agents of human and animal sporotrichosis, were investigated. The interaction of S. brasiliensis and S. schenckii with human monocyte-derived macrophages (hMDMs) was shown to be dependent on the thermolabile serum complement protein C3, which facilitated the phagocytosis of Sporothrix yeast cells through opsonization. The peptidorhamnomannan (PRM) component of the cell walls of these two Sporothrix yeasts was found to be one of their surfaces exposed pathogen-associated molecular pattern (PAMP), leading to activation of the complement system and deposition of C3b on the Sporothrix yeast surfaces. PRM also showed direct interaction with CD11b, the specific component of the complement receptor-3 (CR3). Furthermore, the blockade of CR3 specifically impacted the interleukin (IL)-1ß secretion by hMDM in response to both S. brasiliensis and S. schenckii, suggesting that the host complement system plays an essential role in the inflammatory immune response against these Sporothrix species. Nevertheless, the structural differences in the PRMs of the two Sporothrix species, as revealed by NMR, were related to the differences observed in the host complement activation pathways. Together, this work reports a new PAMP of the cell surface of pathogenic fungi playing a role through the activation of complement system and via CR3 receptor mediating an inflammatory response to Sporothrix species.


Assuntos
Antígenos de Fungos/imunologia , Proteínas do Sistema Complemento/imunologia , Glicoproteínas/imunologia , Macrófagos/imunologia , Sporothrix , Parede Celular/imunologia , Ativação do Complemento , Citocinas/imunologia , Humanos , L-Lactato Desidrogenase/imunologia , Antígeno de Macrófago 1/imunologia , Macrófagos/microbiologia , Moléculas com Motivos Associados a Patógenos/imunologia , Fagocitose
12.
J Healthc Qual Res ; 36(4): 231-239, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33967001

RESUMO

BACKGROUND: A Study related to Safety in Hospitals in the Region of Madrid (ESHMAD) was carried out in order to determine the prevalence, magnitude and characteristics of adverse events in public hospitals. This work aims to define a useful methodology for the multicenter study of adverse events in the Region of Madrid, to set out the preliminary results of the hospital enrollment and to establish a model of a strategy of training of trainers for its implementation. METHODS: ESHMAD was a multicenter, double phase study for the estimation of adverse events and incidents prevalence across the Region of Madrid. First phase comprehended a 1-day cross-sectional prevalence study, in which it was collected, through a screening guide, information about admission, patient characteristics, intrinsic and extrinsic risk factors, and the possibility of an adverse event or incident had happened during the hospitalization. Second phase was a retrospective nested cohort study, in which it was used a Modular Review Form for reviewing the positive screenings of the first phase, identifying in each possible adverse event or incident the classification of the patient safety event, clinical onset, root, and associated causes and factors, impact, and preventability. A pilot study was performed in an Internal Medicine Unit of a tertiary hospital. RESULTS: 34 public hospitals participated, belonging to 6 healthcare categories and with more than 10,000 hospitalisations aggregate capacity. 72 coordinators were enrolled in the strategy of training of trainers, which was performed through five on-site training workshops. In the pilot study, 45.2% patients were identified with at least one positive event of the screening. Of them, 48.1% (25 positive events) were identified as truly AE, with a result of 0.29 EA per analyzed patient. CONCLUSIONS: The ESHMAD protocol allows to estimate the prevalence of adverse events, and the strategy of training of trainers facilitated the spread of the research methodology among the participants.


Assuntos
Hospitais Públicos , Erros Médicos , Estudos de Coortes , Estudos Transversais , Humanos , Projetos Piloto , Estudos Retrospectivos
13.
J Hosp Infect ; 108: 113-119, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33157170

RESUMO

BACKGROUND: The coronavirus disease 2019 pandemic has caused problems with respirator supplies. Re-use may minimize the impact of the shortage, but requires the availability of an efficient and safe decontamination method. AIM: To determine whether low-temperature-steam-2%-formaldehyde (LTSF) sterilization is effective, preserves the properties of filtering facepiece (FFP) respirators and allows safe re-use. METHODS: Fourteen unused FFP2, FFP3 and N95 respirator models were subjected to two cycles of decontamination cycles. After the second cycle, each model was inspected visually and accumulated residual formaldehyde levels were analysed according to EN 14180. After one and two decontamination cycles, the fit factor (FF) of each model was tested, and penetration tests with sodium chloride aerosols were performed on five models. FINDINGS: Decontamination physically altered three of the 14 models. All of the residual formaldehyde values were below the permissible threshold. Irregular decreases and increases in FF were observed after each decontamination cycle. In the sodium chloride aerosol penetration test, three models obtained equivalent or superior results to those of the FFP classification with which they were marketed, both at baseline and after one and two cycles of decontamination, and two models had lower filtering capacity. CONCLUSION: One and two decontamination cycles using LTSF did not alter the structure of most (11/14) respirators tested, and did not degrade the fit or filtration capacity of any of the analysed respirators. The residual formaldehyde levels complied with EN 14180. This reprocessing method could be used in times of shortage of personal protective equipment.


Assuntos
Descontaminação/métodos , Formaldeído/farmacologia , Dispositivos de Proteção Respiratória/virologia , Esterilização/métodos , Adulto , Aerossóis/efeitos adversos , COVID-19/diagnóstico , COVID-19/epidemiologia , COVID-19/prevenção & controle , COVID-19/virologia , Reutilização de Equipamento , Formaldeído/análise , Humanos , Masculino , Máscaras/tendências , Máscaras/virologia , Equipamento de Proteção Individual/provisão & distribuição , Dispositivos de Proteção Respiratória/provisão & distribuição , SARS-CoV-2/genética , Cloreto de Sódio/análise , Vapor/efeitos adversos , Ventiladores Mecânicos/provisão & distribuição , Ventiladores Mecânicos/virologia
14.
Ocul Immunol Inflamm ; 29(7-8): 1591-1598, 2021 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-32657649

RESUMO

Purpose: To assess the efficacy and safety of adalimumab in elderly patients with noninfectious uveitis (NIU).Methods: An observational, retrospective, multicenter study was done. Changes in best-corrected visual acuity (BCVA), inflammatory activity parameters, central retinal thickness (CRT), and the occurrence of adverse events (AE) developed during follow-up were recorded.Results: A total of 82 eyes from 41 patients 60 years of age and older with noninfectious uveitis treated with adalimumab were included. A significant improvement in BCVA (71.5 to 75.4 letters, p = .001) and in CRT (311.1 µm to 265 µm, p = .001) was observed. Moreover, a significant decrease from baseline in the rate of patients with anterior chamber cell (ACC) >0+ (34.6% to 5.7%, p = <0.001) or vitreous haze>0+ (21.3% to 4.3%, p = .002) was determined. AEs were observed in 11 patients (26.8%).Conclusion: Adalimumab can be safe and efficacious for the treatment of NIU in patients 60 years of age and older.


Assuntos
Adalimumab/uso terapêutico , Inibidores do Fator de Necrose Tumoral/uso terapêutico , Uveíte/tratamento farmacológico , Adalimumab/efeitos adversos , Idoso , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento , Inibidores do Fator de Necrose Tumoral/efeitos adversos , Uveíte/fisiopatologia , Acuidade Visual/fisiologia
15.
J Fungi (Basel) ; 6(3)2020 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-32859091

RESUMO

Immune inertness of Aspergillus fumigatus conidia is attributed to its surface rodlet-layer made up of RodAp, characterized by eight conserved cysteine residues forming four disulfide bonds. Earlier, we showed that the conserved cysteine residue point (ccrp) mutations result in conidia devoid of the rodlet layer. Here, we extended our study comparing the surface organization and immunoreactivity of conidia carrying ccrp-mutations with the RODA deletion mutant (∆rodA). Western blot analysis using anti-RodAp antibodies indicated the absence of RodAp in the cytoplasm of ccrp-mutant conidia. Immunolabeling revealed differential reactivity to conidial surface glucans, the ccrp-mutant conidia preferentially binding to α-(1,3)-glucan, ∆rodA conidia selectively bound to ß-(1,3)-glucan; the parental strain conidia showed negative labeling. However, permeability of ccrp-mutants and ∆rodA was similar to the parental strain conidia. Proteomic analyses of the conidial surface exposed proteins of the ccrp-mutants showed more similarities with the parental strain, but were significantly different from the ∆rodA. Ccrp-mutant conidia were less immunostimulatory compared to ∆rodA conidia. Our data suggest that (i) the conserved cysteine residues are essential for the trafficking of RodAp and the organization of the rodlet layer on the conidial surface, and (ii) targeted point mutation could be an alternative approach to study the role of fungal cell-wall genes in host-fungal interaction.

16.
Infect Immun ; 88(9)2020 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-32571987

RESUMO

Even though both cellular and humoral immunities contribute to host defense, the role played by humoral immunity against the airborne opportunistic fungal pathogen Aspergillus fumigatus has been underexplored. In this study, we aimed at deciphering the role of the complement system, the major humoral immune component, against A. fumigatus Mass spectrometry analysis of the proteins extracted from A. fumigatus conidial (asexual spores and infective propagules) surfaces opsonized with human serum indicated that C3 is the major complement protein involved. Flow cytometry and immunolabeling assays further confirmed C3b (activated C3) deposition on the conidial surfaces. Assays using cell wall components of conidia indicated that the hydrophobin RodAp, ß-(1,3)-glucan (BG) and galactomannan (GM) could efficiently activate C3. Using complement component-depleted sera, we showed that while RodAp activates C3 by the alternative pathway, BG and GM partially follow the classical and lectin pathways, respectively. Opsonization facilitated conidial aggregation and phagocytosis, and complement receptor (CR3 and CR4) blockage on phagocytes significantly inhibited phagocytosis, indicating that the complement system exerts a protective role against conidia by opsonizing them and facilitating their phagocytosis mainly through complement receptors. Conidial opsonization with human bronchoalveolar lavage fluid (BALF) confirmed C3 to be the major complement protein interacting with conidia. Nevertheless, complement C2 and mannose-binding lectin (MBL), the classical and lectin pathway components, respectively, were not identified, indicating that BALF activates the alternative pathway on the conidial surface. Moreover, the cytokine profiles were different upon stimulation of phagocytes with serum- and BALF-opsonized conidia, highlighting the importance of studying interaction of conidia with complement proteins in their biological niche.


Assuntos
Aspergillus fumigatus/imunologia , Líquido da Lavagem Broncoalveolar/imunologia , Complemento C3/imunologia , Polissacarídeos Fúngicos/farmacologia , Macrófagos/efeitos dos fármacos , Soro/imunologia , Esporos Fúngicos/imunologia , Aspergilose/genética , Aspergilose/imunologia , Aspergilose/microbiologia , Aspergillus fumigatus/química , Líquido da Lavagem Broncoalveolar/química , Líquido da Lavagem Broncoalveolar/microbiologia , Parede Celular/química , Parede Celular/imunologia , Ativação do Complemento/efeitos dos fármacos , Complemento C3/genética , Citocinas/biossíntese , Citocinas/imunologia , Polissacarídeos Fúngicos/imunologia , Polissacarídeos Fúngicos/isolamento & purificação , Galactose/análogos & derivados , Interações entre Hospedeiro e Microrganismos/imunologia , Humanos , Imunidade Celular , Imunidade Humoral , Integrina alfaXbeta2/genética , Integrina alfaXbeta2/imunologia , Antígeno de Macrófago 1/genética , Antígeno de Macrófago 1/imunologia , Macrófagos/imunologia , Macrófagos/microbiologia , Mananas/imunologia , Mananas/isolamento & purificação , Mananas/farmacologia , Proteínas Opsonizantes/farmacologia , Fagocitose/efeitos dos fármacos , Cultura Primária de Células , Ligação Proteica , Espécies Reativas de Oxigênio , Soro/química , Soro/microbiologia , Esporos Fúngicos/química , beta-Glucanas/imunologia , beta-Glucanas/isolamento & purificação , beta-Glucanas/farmacologia
17.
Arch. Soc. Esp. Oftalmol ; 95(5): 217-222, mayo 2020. tab
Artigo em Espanhol | IBECS | ID: ibc-198610

RESUMO

OBJETIVO: Analizar las cirugías de estrabismo y los resultados durante un año y medio en un hospital terciario. MATERIAL Y MÉTODOS: Estudio retrospectivo de pacientes operados de estrabismo. Se analizó: edad media, sexo, diagnóstico, diplopía, técnica y anestesia, suturas ajustables, resultados, re-intervenciones y tiempo de seguimiento desde la cirugía. Se consideró buen resultado una desviación horizontal < 10 dioptrías prismáticas (dp) y vertical < 5 dp, sin diplopía. RESULTADOS: Se operaron 153 casos, con una edad media de 43,14 ± 25,58 años (61,4% mujeres). El 74,5% eran ≥ 18 años (33,33% ≥ 60). El 51% tenían diplopía. La desviación más frecuente fue horizontal: 83,6%. El diagnóstico más frecuente fue la parálisis de los nervios craneales: 32% (VI nervio: 12,4%), los estrabismos restrictivos representaron un 7,2% y la esotropía asociada a la edad, un 6,5%. Se emplearon suturas ajustables en el 19,7% y anestesia tópica en el 65,4%. El 79,2% obtuvieron buenos resultados al final del seguimiento. Las re-intervenciones fueron el 25,5%. El tiempo medio de seguimiento fue de 11,87 meses ± 6,5. El sexo femenino (p = 0,012) y la cirugía de oblicuo superior (p = 0,017) se asociaron a un peor resultado. CONCLUSIÓN: La cirugía del estrabismo del adulto fue tres veces más frecuente que la de los niños. La tercera parte de los adultos que se operaron eran ≥ 60 años. Las parálisis fueron la patología más frecuente. Las suturas ajustables se emplearon en escaso número de pacientes. Se obtuvieron buenos resultados en la mayoría de los casos


OBJECTIVE: To analyze the strabismus surgeries and the outcomes during a year and a half in a tertiary hospital. MATERIAL AND METHODS: A retrospective study of patients who underwent strabismus surgery. The mean age, sex, diagnosis, diplopia, surgery, anesthesia, adjustable sutures, results, reoperations and follow up time from surgery were analyzed. A good outcome was considered when the final horizontal deviation was less than 10 prism diopters (pd) and the vertical deviation less than 5 pd without diplopia. RESULTS: A total of 153 cases were operated on, mean age: 43.14 ± 25.58 years (61.4%: women).74.5% of patients were ≥ 18 years (33.33% ≥ 60). Diplopia was present in 51% of patients. The most frequent deviation was horizontal: 83.6%. The most frequent diagnosis was cranial nerve palsies: 32% (VI nerve: 12.4%), restrictive strabismus: 7.2%, and the aged related distance esotropia: 6.5%. Adjustable sutures were used in 19.7% of cases and topical anesthesia in 65.4%. Good outcomes was present in 79.2% of cases at the end of follow-up. Reoperations were needed in 25.5%. Follow-up evolution time was 11.87 months ± 6.5. The sex female (P = .012) and the oblique superior surgery (P = .017) were associated with bad outcome. CONCLUSIÓN: The adult strabismus surgery was three times more frequent than the children strabismus surgery. The third of the adults that were operated on were ≥ 60 years. The cranial nerve palsies were the most frequent diagnosis. Adjustable sutures were rarely used. Good outcomes were obtained in most of the patients at the end of follow-up


Assuntos
Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Esotropia/diagnóstico , Esotropia/cirurgia , Diplopia/diagnóstico , Diplopia/cirurgia , Procedimentos Cirúrgicos Oftalmológicos/tendências , Estudos Retrospectivos , Estrabismo/diagnóstico , Estrabismo/cirurgia , Complicações Pós-Operatórias , Análise Multivariada , Procedimentos Cirúrgicos Oftalmológicos/estatística & dados numéricos , Resultado do Tratamento
18.
Arch Soc Esp Oftalmol (Engl Ed) ; 95(5): 217-222, 2020 May.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-32063418

RESUMO

OBJECTIVE: To analyze the strabismus surgeries and the outcomes during a year and a half in a tertiary hospital. MATERIAL AND METHODS: A retrospective study of patients who underwent strabismus surgery. The mean age, sex, diagnosis, diplopia, surgery, anesthesia, adjustable sutures, results, reoperations and follow up time from surgery were analyzed. A good outcome was considered when the final horizontal deviation was less than 10prism diopters (pd) and the vertical deviation less than 5pd without diplopia. RESULTS: A total of 153 cases were operated on, mean age: 43.14 ±25.58years (61.4%: women). 74.5% of patients were ≥18years (33.33% ≥60). Diplopia was present in 51% of patients. The most frequent deviation was horizontal: 83.6%. The most frequent diagnosis was cranial nerve palsies: 32% (VI nerve: 12.4%), restrictive strabismus: 7.2%, and the aged related distance esotropia: 6.5%. Adjustable sutures were used in 19.7% of cases and topical anesthesia in 65.4%. Good outcomes was present in 79.2% of cases at the end of follow-up. Reoperations were needed in 25.5%. Follow-up evolution time was 11.87 months ±6.5. The sex female (P=.012) and the oblique superior surgery (P=.017) were associated with bad outcome. CONCLUSION: The adult strabismus surgery was three times more frequent than the children strabismus surgery. The third of the adults that were operated on were ≥60 years. The cranial nerve palsies were the most frequent diagnosis. Adjustable sutures were rarely used. Good outcomes were obtained in most of the patients at the end of follow-up.


Assuntos
Estrabismo/cirurgia , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Procedimentos Cirúrgicos Oftalmológicos/tendências , Estudos Retrospectivos , Centros de Atenção Terciária , Adulto Jovem
19.
Toxicon ; 167: 184-191, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31226259

RESUMO

A peptide (Cn29) from the venom of the scorpion Centruroides noxius (about 2% of the soluble venom) was purified and its primary and three-dimensional structures were determined. The peptide contains 27 amino acids with primary sequence: LCLSCRGGDYDCRVKGTCENGKCVCGS. The peptide is tightly packed by three disulfide linkages formed between C2-C23, C5-C18 and C12-C25. Since the native peptide was obtained in limited amounts, the full synthetic peptide was prepared using the standard F-moc-based solid phase synthesis method of Merrifield. The native and synthetic peptides were shown to be identical by sequencing, HPLC separation and mass spectrometry. The solution structure of the peptide solved from NMR data shows that it consists of a well-defined N-terminal region without regular secondary structure extending from Leu 1 to Asp 9, followed by a short helical fragment from Tyr10 to Val14 and two short ß strands (Thr17-Glu19 and Lys22-Val24). The primary and tertiary structures of Cn29 are different from all other scorpion peptides described in the literature. Transcriptome analysis of RNA obtained from C. noxius confirmed the expression of a gene coding for Cn29 in its venom gland. Initial experiments were conducted to identify its possible function: lethality tests in mice and insects as well as ion-channel binding using in vitro electrophysiological assays. None of the physiological or biological tests displayed any activity for this peptide, which at present is considered to be another orphan peptide found in scorpion venoms. The peptide is thus the first example of a novel structural component present in scorpion venoms.


Assuntos
Peptídeos/química , Venenos de Escorpião/química , Sequência de Aminoácidos , Animais , Gryllidae , Camundongos , Modelos Moleculares , Peptídeos/isolamento & purificação , Escorpiões , Análise de Sequência de Proteína , Testes de Toxicidade
20.
Behav Brain Res ; 370: 111941, 2019 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-31078617

RESUMO

Amblyopia or lazy eye is a neurodevelopmental disorder that arises during the infancy and is caused by the interruption of binocular sensory activity before maturation of the nervous system. This impairment causes long-term deterioration of visual skills, particularly visual acuity and depth perception. Although visual function recovery has been supposed to be decreased with age as consequence of reduced neuronal plasticity, recent studies have shown that it is possible to promote plasticity and neurorestoration in the adult brain. Thus, transcranial direct current stimulation (tDCS) has been shown effective to treat amblyopia in the adulthood. In the present work we used postnatal monocular deprivation in Long Evans rats as an experimental model of amblyopia and the cliff test task to assess depth perception. Functional brain imaging PET was used to assess the effect of tDCS on cortical and subcortical activity. Visually deprived animals ability to perceive depth in the cliff test was significantly reduced in comparison to their controls. However, after 8 sessions of tDCS applied through 8 consecutive days, depth perception of amblyopic treated animals improved reaching control level. PET data showed 18F-FDG uptake asymmetries in the visual cortex of amblyopic animals, which disappeared after tDCS treatment. The possibility of cortical reorganization and stereoscopy recovery following brain stimulation points at tDCS as a useful strategy for treating amblyopia in adulthood. Furthermore, monocular deprivation in Long Evans rats is a valuable research model to study visual cortex mechanisms involved in depth perception and neural restoration after brain stimulation.


Assuntos
Ambliopia/fisiopatologia , Ambliopia/terapia , Estimulação Transcraniana por Corrente Contínua/métodos , Animais , Percepção de Profundidade/fisiologia , Masculino , Plasticidade Neuronal/fisiologia , Ratos , Ratos Long-Evans , Recuperação de Função Fisiológica/fisiologia , Privação Sensorial/fisiologia , Visão Ocular , Acuidade Visual/fisiologia , Córtex Visual/fisiologia
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