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1.
Sensors (Basel) ; 23(19)2023 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-37837133

RESUMO

A low-power long-term ambulatory ECG monitor was developed for the acquisition, storage and processing of three simultaneous leads DI, aVF and V2 with a beat-to-beat heart rate measurement in real time. It provides long-term continuous ECG recordings until 84 h. The monitor uses a QRS complex detection algorithm based on the continuous wavelet transform with splines, which automatically selects the scale for the analysis of ECG records with different sampling frequencies. It includes a lead-off detection to continuously monitor the electrode connections and a real-time system of visual and acoustic alarms to alert users of abnormal conditions in its operation. The monitor presented is based in an ADS1294 analogue front end with four channels, 24-bit analog-to-digital converters and programmable gain amplifiers, a low-power dual-core ESP32 microcontroller, a microSD memory for data storage in a range of 4 GB to 32 GB and a 1.4 in thin-film transistor liquid crystal display (LCD) variant with a resolution of 128 × 128 pixels. It has programmable sampling rates of 250, 500 and 1000 Hz; a bandwidth of 0 Hz to 50% of the selected sampling rate; a CMRR of -105 dB; an input margin of ±2.4 V; a resolution of 286 nV; and a current consumption of 50 mA for an average battery life of 84 h. The ambulatory ECG monitor was evaluated with the commercial data-acquisition system BIOPAC MP36 and its module for ECG LABEL SS2LB, simultaneously comparing the morphologies of two ECG records and obtaining a correlation of 91.78%. For the QRS detection in real time, the implemented algorithm had an error less than 5%. The developed ambulatory ECG monitor can be used for the analysis of the dynamics of the heart rate variability in long-term ECG records and for the development of one's own databases of ECG recordings of normal subjects and patients with cardiovascular and noncardiovascular diseases.


Assuntos
Eletrocardiografia Ambulatorial , Processamento de Sinais Assistido por Computador , Humanos , Frequência Cardíaca/fisiologia , Coração/fisiologia , Eletrocardiografia , Arritmias Cardíacas/diagnóstico , Algoritmos
2.
Micromachines (Basel) ; 14(9)2023 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-37763911

RESUMO

Cardiovascular diseases are currently the leading cause of death worldwide. Thus, there is a need for non-invasive ambulatory (Holter) ECG monitors with automatic measurements of ECG intervals to evaluate electrocardiographic abnormalities of patients with cardiac diseases. This work presents the implementation of algorithms in an FPGA for beat-to-beat heart rate and RT interval measurements based on the continuous wavelet transform (CWT) with splines for a prototype of an ambulatory ECG monitor of three leads. The prototype's main elements are an analog-digital converter ADS1294, an FPGA of Xilinx XC7A35T-ICPG236C of the Artix-7 family of low consumption, immersed in a low-scale Cmod-A7 development card integration, an LCD display and a micro-SD memory of 16 Gb. A main state machine initializes and manages the simultaneous acquisition of three leads from the ADS1294 and filters the signals using a FIR filter. The algorithm based on the CWT with splines detects the QRS complex (R or S wave) and then the T-wave end using a search window. Finally, the heart rate (60/RR interval) and the RT interval (from R peak to T-wave end) are calculated for analysis of its dynamics. The micro-SD memory stores the three leads and the RR and RT intervals, and an LCD screen displays the beat-to-beat values of heart rate, RT interval and the electrode connection. The algorithm implemented on the FPGA achieved satisfactory results in detecting different morphologies of QRS complexes and T wave in real time for the analysis of heart rate and RT interval dynamics.

3.
Molecules ; 27(18)2022 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-36144683

RESUMO

Starch is a biocompatible and economical biopolymer in which interest has been shown in obtaining electrospun fibers. This research reports that cassava (CEX) and pea (PEX) starches pretreated by means of reactive extrusion (REX) improved the starches rheological properties and the availability of amylose to obtain fibers. Solutions of CEX and PEX (30-36% w/v) in 38% v/v formic acid were prepared and the rheological properties and electrospinability were studied. The rheological values indicated that to obtain continuous fibers without beads, the entanglement concentration (Ce) must be 1.20 and 1.25 times the concentration of CEX and PEX, respectively. In CEX, a higher amylose content and lower viscosity were obtained than in PEX, which resulted in a greater range of concentrations (32-36% w/v) to obtain continuous fibers without beads with average diameters ranging from 316 ± 65 nm to 394 ± 102 nm. In PEX, continuous fibers without beads were obtained only at 34% w/v with an average diameter of 170 ± 49 nm. This study showed that starches (20-35% amylose) pretreated through REX exhibited electrospinning properties to obtain fibers, opening the opportunity to expand their use in food, environmental, biosensor, and biomedical applications, as vehicles for the administration of bioactive compounds.


Assuntos
Manihot , Amilose , Pisum sativum , Amido , Viscosidade
4.
Cancer Cell ; 39(9): 1202-1213.e6, 2021 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-34329585

RESUMO

Studies suggest that the efficacy of cancer chemotherapy and immunotherapy is influenced by intestinal bacteria. However, the influence of the microbiome on radiation therapy is not as well understood, and the microbiome comprises more than bacteria. Here, we find that intestinal fungi regulate antitumor immune responses following radiation in mouse models of breast cancer and melanoma and that fungi and bacteria have opposite influences on these responses. Antibiotic-mediated depletion or gnotobiotic exclusion of fungi enhances responsiveness to radiation, whereas antibiotic-mediated depletion of bacteria reduces responsiveness and is associated with overgrowth of commensal fungi. Further, elevated intratumoral expression of Dectin-1, a primary innate sensor of fungi, is negatively associated with survival in patients with breast cancer and is required for the effects of commensal fungi in mouse models of radiation therapy.


Assuntos
Antifúngicos/administração & dosagem , Bactérias/classificação , Neoplasias da Mama/terapia , Fungos/efeitos dos fármacos , Lectinas Tipo C/genética , Melanoma/terapia , Animais , Antifúngicos/farmacologia , Bactérias/imunologia , Neoplasias da Mama/imunologia , Neoplasias da Mama/microbiologia , Terapia Combinada , Regulação para Baixo , Feminino , Fungos/classificação , Fungos/imunologia , Microbioma Gastrointestinal/efeitos dos fármacos , Microbioma Gastrointestinal/efeitos da radiação , Regulação Neoplásica da Expressão Gênica/efeitos da radiação , Humanos , Melanoma/imunologia , Melanoma/microbiologia , Camundongos , Simbiose , Linfócitos T/metabolismo , Macrófagos Associados a Tumor/metabolismo , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/efeitos da radiação , Ensaios Antitumorais Modelo de Xenoenxerto
5.
J Leukoc Biol ; 109(1): 161-172, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32941658

RESUMO

Malassezia spp. are common eukaryotic yeasts that colonize mammalian skin. Recently, the authors and others have observed that Malassezia globosa and Malassezia restricta can be found in the intestines in the context of certain diseases, including Crohn's disease and pancreatic cancer. In order to better understand the nature of innate inflammatory responses to these yeasts, inflammatory responses induced by M. restricta and M. globosa in mouse bone marrow-derived Mϕs (BMDM) and dendritic cells (BMDC) are evaluated. While Malassezia yeasts induce proinflammatory cytokine production from both Mϕs and dendritic cells, the levels of production from BMDC were more pronounced. Both M. restricta and M. globosa activated inflammatory cytokine production from BMDC in large part through Dectin2 and CARD9 signaling, although additional receptors appear to be involved in phagocytosis and activation of reactive oxygen production in response to the yeasts. Both M. restricta and M. globosa stimulate production of pro-IL-1ß as well as activation of the NLRP3 inflammasome. NLRP3 inflammasome activation by Malassezia fungi requires SYK signaling, potassium efflux and actin rearrangement. Together, the data further the understanding of the coordinated involvement of multiple innate immune receptors in recognizing Malassezia globosa and Malassezia restricta and orchestrating phagocyte inflammatory and antimicrobial responses.


Assuntos
Inflamassomos/imunologia , Inflamação/imunologia , Malassezia/imunologia , Micoses/imunologia , Fagócitos/imunologia , Animais , Citocinas/imunologia , Camundongos , Proteína 3 que Contém Domínio de Pirina da Família NLR/imunologia
6.
Polymers (Basel) ; 12(9)2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32882974

RESUMO

The aim of this work is to structurally characterize chitosan-zinc oxide nanoparticles (CS-ZnO NPs) films in a wide range of NPs concentration (0-20 wt.%). Dielectric, conductivity, mechanical, and piezoelectric properties are assessed by using thermogravimetry, FTIR, XRD, mechanical, and dielectric spectroscopy measurements. These analyses reveal that the dielectric constant, Young's modulus, and piezoelectric constant (d33) exhibit a strong dependence on nanoparticle concentration such that maximum values of referred properties are obtained at 15 wt.% of ZnO NPs. The piezoelectric coefficient d33 in CS-ZnO nanocomposite films with 15 wt.% of NPs (d33 = 65.9 pC/N) is higher than most of polymer-ZnO nanocomposites because of the synergistic effect of piezoelectricity of NPs, elastic properties of CS, and optimum NPs concentration. A three-phase model is used to include the chitosan matrix, ZnO NPs, and interfacial layer with dielectric constant higher than that of neat chitosan and ZnO. This layer between nanoparticles and matrix is due to strong interactions between chitosan's side groups with ZnO NPs. The understanding of nanoscale properties of CS-ZnO nanocomposites is important in the development of biocompatible sensors, actuators, nanogenerators for flexible electronics and biomedical applications.

7.
PLoS Pathog ; 16(8): e1008733, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32817694

RESUMO

Staphylococcus aureus (S. aureus) is one of the most common bacterial infections worldwide, and antibiotic resistant strains such as Methicillin-Resistant S. aureus (MRSA) are a major threat and burden to public health. MRSA not only infects immunocompromised patients but also healthy individuals and has rapidly spread from the healthcare setting to the outside community. However, all vaccines tested in clinical trials to date have failed. Immunocompromised individuals such as patients with HIV or decreased levels of CD4+ T cells are highly susceptible to S. aureus infections, and they are also at increased risk of developing fungal infections. We therefore wondered whether stimulation of antifungal immunity might promote the type of immune responses needed for effective host defense against S. aureus. Here we show that vaccination of mice with a fungal ß-glucan particle (GP) loaded with S. aureus antigens provides protective immunity to S. aureus. We generated glucan particles loaded with the four S. aureus proteins ClfA, IsdA, MntC, and SdrE, creating the 4X-SA-GP vaccine. Vaccination of mice with three doses of 4X-SA-GP promoted protection in a systemic model of S. aureus infection with a significant reduction in the bacterial burden in the spleen and kidneys. 4X-SA-GP vaccination induced antigen-specific Th1 and Th17 CD4+ T cell and antibody responses and provided long-term protection. This work suggests that the GP vaccine system has potential as a novel approach to developing vaccines for S. aureus.


Assuntos
Saccharomyces cerevisiae/imunologia , Infecções Estafilocócicas/imunologia , Vacinas Antiestafilocócicas/imunologia , Staphylococcus aureus/imunologia , Animais , Anticorpos Antibacterianos/imunologia , Coagulase/administração & dosagem , Coagulase/genética , Coagulase/imunologia , Feminino , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Saccharomyces cerevisiae/química , Infecções Estafilocócicas/microbiologia , Vacinas Antiestafilocócicas/administração & dosagem , Vacinas Antiestafilocócicas/genética , Staphylococcus aureus/genética , Células Th1/imunologia , Células Th17/imunologia , Vacinação , beta-Glucanas/administração & dosagem , beta-Glucanas/imunologia
8.
Colloids Surf B Biointerfaces ; 196: 111296, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32771819

RESUMO

Herein we report the synthesis of a piezopolymer composed of chitosan (CS)/hydroxylated BaTiO3 (OH-BTO) nanoparticles with enhanced biocompatibility, non-toxicity, and piezoelectric behavior that can be advantageously used in biomedical applications. Our CS/OH-BTO nanocomposites exhibit piezoelectric coefficient (d33 = 11.29 pC/N) between those of dry skin (0.05-0.19 pC/N) and bone (4-11 pC/N), demonstrating biocompatibility in contact with human fibroblasts (HF) cells after 24 h. SEM, XRD, FTIR and Raman measurements were performed to assess the mechanism of interaction between CS matrix and OH-BTO NPs and their correlation with the biological responses. Cytotoxicity assays with HF cells reveal that hydroxylation of BTO NPs does not affect the cell viability of CS/OH-BTO films with NPs concentration from 1 to 30 wt.%. In contrast, non-hydroxylated BTO NPs showed significant cell damage, which could be traced to uncontrollable NPs agglomeration. This behavior suggests that CS/OH-BTO nanocomposites can act as active material that promotes cell growth and can be used for biomedical purposes.


Assuntos
Quitosana , Antibacterianos , Compostos de Bário , Humanos , Engenharia Tecidual , Titânio
9.
Beilstein J Nanotechnol ; 11: 703-716, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32461872

RESUMO

In this work, a high-resolution atomic force acoustic microscopy imaging technique is developed in order to obtain the local indentation modulus at the nanoscale level. The technique uses a model that gives a qualitative relationship between a set of contact resonance frequencies and the indentation modulus. It is based on white-noise excitation of the tip-sample interaction and uses system theory for the extraction of the resonance modes. During conventional scanning, for each pixel, the tip-sample interaction is excited with a white-noise signal. Then, a fast Fourier transform is applied to the deflection signal that comes from the photodiodes of the atomic force microscopy (AFM) equipment. This approach allows for the measurement of several vibrational modes in a single step with high frequency resolution, with less computational cost and at a faster speed than other similar techniques. This technique is referred to as stochastic atomic force acoustic microscopy (S-AFAM), and the frequency shifts of the free resonance frequencies of an AFM cantilever are used to determine the mechanical properties of a material. S-AFAM is implemented and compared with a conventional technique (resonance tracking-atomic force acoustic microscopy, RT-AFAM). A sample of a graphite film on a glass substrate is analyzed. S-AFAM can be implemented in any AFM system due to its reduced instrumentation requirements compared to conventional techniques.

10.
Cell Host Microbe ; 25(3): 377-388.e6, 2019 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-30850233

RESUMO

Inflammatory bowel disease (IBD) is characterized by alterations in the intestinal microbiota and altered immune responses to gut microbiota. Evidence is accumulating that IBD is influenced by not only commensal bacteria but also commensal fungi. We characterized fungi directly associated with the intestinal mucosa in healthy people and Crohn's disease patients and identified fungi specifically abundant in patients. One of these, the common skin resident fungus Malassezia restricta, is also linked to the presence of an IBD-associated polymorphism in the gene for CARD9, a signaling adaptor important for anti-fungal defense. M. restricta elicits innate inflammatory responses largely through CARD9 and is recognized by Crohn's disease patient anti-fungal antibodies. This yeast elicits strong inflammatory cytokine production from innate cells harboring the IBD-linked polymorphism in CARD9 and exacerbates colitis via CARD9 in mouse models of disease. Collectively, these results suggest that targeting specific commensal fungi may be a therapeutic strategy for IBD.


Assuntos
Colite/patologia , Colite/fisiopatologia , Doença de Crohn/patologia , Doença de Crohn/fisiopatologia , Trato Gastrointestinal/microbiologia , Malassezia/crescimento & desenvolvimento , Malassezia/isolamento & purificação , Animais , Proteínas Adaptadoras de Sinalização CARD/metabolismo , Citocinas/metabolismo , Modelos Animais de Doenças , Camundongos
11.
Curr Opin Gastroenterol ; 34(6): 398-403, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30299290

RESUMO

PURPOSE OF REVIEW: The intestinal microbiota plays a central role in inflammatory diseases of the gut. Although most investigations regarding how the mucosal immune system interacts with the microbiota have focused on bacteria, recent studies are elucidating the additional role of commensal fungi in health and disease in the gut. RECENT FINDINGS: New technical approaches are defining the makeup of the fungal communities in the intestines of humans and mice. The reported composition of these communities is influenced by the approaches used to define the fungi. Changes in the intestinal mycobiota are associated with gut inflammation in patients with inflammatory bowel disease and in mouse models of colitis. Recent studies are beginning to elucidate the mechanisms by which the mucosal immune system interacts with and is influenced by intestinal fungi. SUMMARY: Studies clearly demonstrate the presence of intestinal fungi and document the ability of the mucosal immune system to recognize and respond to fungi. Future studies will further investigate whether intestinal fungi directly influence intestinal disease and what cellular, molecular, and genetic mechanisms contribute.


Assuntos
Fungos/imunologia , Microbioma Gastrointestinal/imunologia , Doenças Inflamatórias Intestinais/imunologia , Mucosa Intestinal/imunologia , Interações entre Hospedeiro e Microrganismos , Humanos , Imunidade nas Mucosas , Doenças Inflamatórias Intestinais/microbiologia , Mucosa Intestinal/microbiologia
12.
PLoS Pathog ; 14(9): e1007260, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30235351

RESUMO

The gastrointestinal microbiota influences immune function throughout the body. The gut-lung axis refers to the concept that alterations of gut commensal microorganisms can have a distant effect on immune function in the lung. Overgrowth of intestinal Candida albicans has been previously observed to exacerbate allergic airways disease in mice, but whether subtler changes in intestinal fungal microbiota can affect allergic airways disease is less clear. In this study we have investigated the effects of the population expansion of commensal fungus Wallemia mellicola without overgrowth of the total fungal community. Wallemia spp. are commonly found as a minor component of the commensal gastrointestinal mycobiota in both humans and mice. Mice with an unaltered gut microbiota community resist population expansion when gavaged with W. mellicola; however, transient antibiotic depletion of gut microbiota creates a window of opportunity for expansion of W. mellicola following delivery of live spores to the gastrointestinal tract. This phenomenon is not universal as other commensal fungi (Aspergillus amstelodami, Epicoccum nigrum) do not expand when delivered to mice with antibiotic-depleted microbiota. Mice with Wallemia-expanded gut mycobiota experienced altered pulmonary immune responses to inhaled aeroallergens. Specifically, after induction of allergic airways disease with intratracheal house dust mite (HDM) antigen, mice demonstrated enhanced eosinophilic airway infiltration, airway hyperresponsiveness (AHR) to methacholine challenge, goblet cell hyperplasia, elevated bronchoalveolar lavage IL-5, and enhanced serum HDM IgG1. This phenomenon occurred with no detectable Wallemia in the lung. Targeted amplicon sequencing analysis of the gastrointestinal mycobiota revealed that expansion of W. mellicola in the gut was associated with additional alterations of bacterial and fungal commensal communities. We therefore colonized fungus-free Altered Schaedler Flora (ASF) mice with W. mellicola. ASF mice colonized with W. mellicola experienced enhanced severity of allergic airways disease compared to fungus-free control ASF mice without changes in bacterial community composition.


Assuntos
Basidiomycota/imunologia , Basidiomycota/patogenicidade , Microbioma Gastrointestinal/imunologia , Micobioma/imunologia , Hipersensibilidade Respiratória/etiologia , Alérgenos/administração & dosagem , Animais , Antibacterianos/efeitos adversos , Antígenos de Dermatophagoides/administração & dosagem , Basidiomycota/crescimento & desenvolvimento , Modelos Animais de Doenças , Microbiologia Ambiental , Feminino , Microbioma Gastrointestinal/efeitos dos fármacos , Microbioma Gastrointestinal/genética , Vida Livre de Germes/imunologia , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Micobioma/genética , Hipersensibilidade Respiratória/imunologia , Hipersensibilidade Respiratória/microbiologia , Simbiose/imunologia
13.
Cell Host Microbe ; 22(2): 156-165, 2017 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-28799901

RESUMO

Fungi are increasingly being recognized as common members of the microbiomes found on nearly all mucosal surfaces, and interest is growing in understanding how these organisms may contribute to health and disease. In this review, we investigate recent developments in our understanding of the fungal microbiota or "mycobiota" including challenges faced in characterizing it, where these organisms are found, their diversity, and how they interact with host immunity. Growing evidence indicates that, like the bacterial microbiota, the fungal microbiota is often altered in disease states, and increasingly studies are being designed to probe the functional consequences of such fungal dysbiosis on health and disease.


Assuntos
Fungos/fisiologia , Interações Hospedeiro-Patógeno/imunologia , Simbiose/imunologia , Bactérias/imunologia , DNA Fúngico , Disbiose/imunologia , Disbiose/microbiologia , Trato Gastrointestinal/imunologia , Trato Gastrointestinal/microbiologia , Humanos , Imunidade nas Mucosas , Pneumopatias/imunologia , Pneumopatias/microbiologia , Síndrome Metabólica/imunologia , Síndrome Metabólica/microbiologia , Interações Microbianas , Microbiota/imunologia , Sistema Respiratório/imunologia , Sistema Respiratório/microbiologia , Pele/microbiologia , Dermatopatias/imunologia , Dermatopatias/microbiologia , Sistema Urogenital/imunologia , Sistema Urogenital/microbiologia
14.
J Clin Med Res ; 9(8): 701-708, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28725319

RESUMO

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is a consistently progressive, ultimately fatal disease for which no treatment exists capable of either reversing or even interrupting its course. It afflicts more than 5% of the population in many countries, and it accordingly represents the third most frequent cause of death in the US, where it accounts for more than 600 billion in health care costs, morbidity, and mortality. Adipose tissue contains within its stromal compartment a high abundance of adipose stem/stromal cells (ASCs), which can be readily separated from the adipocyte population by methods which require less than 2 h of processing time and yield a concentrated cellular preparation termed the stromal vascular fraction (SVF). The SVF contains all cellular elements of fat, excluding adipocytes. Recent clinical studies have begun to explore the feasibility and safety of the local injection or intravascular delivery of SVF or more purified populations of ASCs derived by culture protocols. Several pre-clinical studies have demonstrated a remarkable ability of ASC to nearly fully ameliorate the progress of emphysema due to cigarette smoke exposure as well as other causes. However, no prior clinical studies have evaluated the safety of administration of either ASC or SVF in subjects with COPD. We hypothesized that harvest, isolation, and immediate intravenous infusion of autologous SVF would be feasible and safe in subjects with COPD; and that such an approach, if ultimately determined to be efficacious as well as safe, would provide a highly practical method for treatment of COPD. METHODS: In this study, an initial phase I trial evaluating the early and delayed safety of SVF infusion was performed. Twelve subjects were enrolled in the study, in which adipose tissue was harvested using standard liposuction techniques, followed by SVF isolation and intravenous infusion of 150 - 300 million cells. Standardized questionnaires were administered to study feasibility as well as immediate and delayed outcomes and adverse events as primary endpoints. Secondary endpoints included subjective wellness and attitudes towards the procedure, as well as willingness to undergo the procedure a second time. The follow-up time ranged from 3 to 12 months, averaging 12 months. RESULTS: Of the 12 subjects, only one experienced an immediate adverse event, related to bruising from the liposuction. No observed pulmonary or cardiac issues were observed as related to the procedure. There were no deaths over the 12-month study period, and none identified in the subsequent telephonic follow-up. Attitudes toward the procedure were predominantly positive, and 92% of the study subjects expressed a desire to undergo the procedure a second time. CONCLUSIONS: This study is the first to demonstrate safety of SVF infusion in humans with serious pulmonary disease. Specifically, the use of intravenous infusion as a route to achieve pulmonary cellular targeting did not lead to clinical pulmonary compromise. The intravenous administration of SVF should be further explored as a potentially feasible and safe method for delivery leading to possible therapeutic benefit.

15.
Mater Sci Eng C Mater Biol Appl ; 76: 897-907, 2017 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-28482605

RESUMO

Collagen and elastin are the two most abundant proteins in the human body, and as biomaterials offer fascinating properties to composite materials. More detailed investigations including these biomaterials within reinforced composites are still needed. This report describes physicochemical properties of fibers composed of collagen type I, collagen III, elastin and polycaprolactone (PCL). Prior to the electrospinning process, PCL was functionalized through covalent attachment of -NH2 groups by aminolysis reaction with hexamentilendiamine. The fibers were fabricated by electrospinning technique set up with a non-conventional collector. A morphological comparative study was developed at different rations of collagen type I, observing in some cases two populations of fibers. The diameters and morphology were analyzed by SEM, observing a wide array of nanostructures with diameters of ~310 to 693nm. Chemical characterization was assessed by FT-IR spectroscopy and the functionalized PCL was characterized through ninhydrin assay resulting in 0.36mM NH2/mg fiber. Swelling tests were performed for 24h, obtaining 320% for the majority of the fibers indicating morphological stability and good water uptake. In addition, contact angle analysis demonstrated adequate permeability and differences for each system depending mainly upon the type of biopolymer incorporated and the functionalization of PCL, ranging the values from 108° to 17°. Moreover, differential scanning calorimetry results showed a melting temperature (Tm) of ~60°C. The onset degradation temperatures (Td,onset) ranged between 115 and 148°C, and were obtained by thermogravimetric analysis. The local mechanical properties of individual fibers were quantified by atomic force acoustic microscopy. These results propose that the physicochemical and mechanical properties of these scaffolds offer the possibility for enhanced biological activity Thus, they have a great potential as candidate scaffolds in tissue engineering applications.


Assuntos
Nanofibras , Fenômenos Químicos , Colágeno , Elastina , Poliésteres , Espectroscopia de Infravermelho com Transformada de Fourier , Engenharia Tecidual , Alicerces Teciduais
16.
J Immunol ; 198(10): 4036-4045, 2017 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-28411186

RESUMO

Type I IFNs are a cytokine family essential for antiviral defense. More recently, type I IFNs were shown to be important during bacterial infections. In this article, we show that, in addition to known cytokine functions, IFN-ß is antimicrobial. Parts of the IFN-ß molecular surface (especially helix 4) are cationic and amphipathic, both classic characteristics of antimicrobial peptides, and we observed that IFN-ß can directly kill Staphylococcus aureus Further, a mutant S. aureus that is more sensitive to antimicrobial peptides was killed more efficiently by IFN-ß than was the wild-type S. aureus, and immunoblotting showed that IFN-ß interacts with the bacterial cell surface. To determine whether specific parts of IFN-ß are antimicrobial, we synthesized IFN-ß helix 4 and found that it is sufficient to permeate model prokaryotic membranes using synchrotron x-ray diffraction and that it is sufficient to kill S. aureus These results suggest that, in addition to its well-known signaling activity, IFN-ß may be directly antimicrobial and be part of a growing family of cytokines and chemokines, called kinocidins, that also have antimicrobial properties.


Assuntos
Antibacterianos/farmacologia , Membrana Celular/efeitos dos fármacos , Interferon beta/fisiologia , Staphylococcus aureus/efeitos dos fármacos , Animais , Peptídeos Catiônicos Antimicrobianos/química , Peptídeos Catiônicos Antimicrobianos/farmacologia , Humanos , Interferon beta/química , Interferon beta/metabolismo , Interferon beta/farmacologia , Camundongos , Testes de Sensibilidade Microbiana , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/genética , Difração de Raios X
17.
Annu Rev Pathol ; 12: 359-385, 2017 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-28068483

RESUMO

Fungi are ubiquitous in our environment, and a healthy immune system is essential to maintain adequate protection from fungal infections. When this protection breaks down, superficial and invasive fungal infections cause diseases that range from irritating to life-threatening. Millions of people worldwide develop invasive infections during their lives, and mortality for these infections often exceeds 50%. Nevertheless, we are normally colonized with many of the same disease-causing fungi (e.g., on the skin or in the gut). Recent research is dramatically expanding our understanding of the mechanisms by which our immune systems interact with these organisms in health and disease. In this review, we discuss what is currently known about where and how the immune system interacts with common fungi.


Assuntos
Imunidade Adaptativa/imunologia , Doença/etiologia , Fungos/imunologia , Imunidade Inata/imunologia , Micoses/complicações , Micoses/imunologia , Animais , Humanos
18.
Cell Host Microbe ; 19(6): 865-73, 2016 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-27237365

RESUMO

Compared to bacteria, the role of fungi within the intestinal microbiota is poorly understood. In this study we investigated whether the presence of a "healthy" fungal community in the gut is important for modulating immune function. Prolonged oral treatment of mice with antifungal drugs resulted in increased disease severity in acute and chronic models of colitis, and also exacerbated the development of allergic airway disease. Microbiota profiling revealed restructuring of fungal and bacterial communities. Specifically, representation of Candida spp. was reduced, while Aspergillus, Wallemia, and Epicoccum spp. were increased. Oral supplementation with a mixture of three fungi found to expand during antifungal treatment (Aspergillus amstelodami, Epicoccum nigrum, and Wallemia sebi) was sufficient to recapitulate the exacerbating effects of antifungal drugs on allergic airway disease. Taken together, these results indicate that disruption of commensal fungal populations can influence local and peripheral immune responses and enhance relevant disease states.


Assuntos
Antifúngicos/efeitos adversos , Disbiose/induzido quimicamente , Disbiose/imunologia , Fungos/efeitos dos fármacos , Fungos/imunologia , Intestinos/microbiologia , Anfotericina B/efeitos adversos , Anfotericina B/farmacologia , Animais , Antifúngicos/farmacologia , Bactérias/efeitos dos fármacos , Sequência de Bases , Colite/imunologia , Colite/microbiologia , Suplementos Nutricionais , Hipersensibilidade a Drogas/imunologia , Hipersensibilidade a Drogas/microbiologia , Fluconazol/efeitos adversos , Fluconazol/farmacologia , Fungos/genética , Microbioma Gastrointestinal/efeitos dos fármacos , Microbioma Gastrointestinal/imunologia , Hipersensibilidade/imunologia , Hipersensibilidade/microbiologia , Camundongos , Camundongos Endogâmicos C57BL
19.
Surg Technol Int ; 27: 116-22, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26680388

RESUMO

A new restrictive procedure has emerged over the last decade known as the total vertical gastric plication or greater curvature plication (GCP). After our initial experience, the original technique was modified and a new standardized procedure was registered as the Stomach Sparing Gastric Sleeve™ (SSGS). The SSGS reduces the capacity of the stomach by in-folding the greater curvature with containment sutures, creating a sleeve-like stomach. Between March 2012 and August 2015 patients that met the National Institutes of Health (NIH) criteria for gastric banding underwent treatment with the SSGS. The standardized technique requires the use of a customized fenestrated orogastric calibration device. The stomach is then imbricated or in-folded in two layers and containment non-absorbable sutures are placed longitudinally. The two layers of non-absorbable sutures are continuous starting 1 cm below the esophageal gastric (EG) junction and continued distally 3-4 cm from the pylorus spaced evenly at 1 cm intervals and sero-muscular thickness. Symmetry of anteroposterior distribution is also observed leading to the formation of a sleeve-like shaped stomach. Initial and subsequent weight (kg), body mass index (Kg/m²), excess weight loss (%EWL) and complications were recorded. Repeated measures of analysis of variance (ANOVA) were used to assess weight change. The SSGS was performed on the last 624 cases (mean age 43.1±11.6 years). The follow-up time was 3 years, with an %EWL of 56.36±21.83 during the first year and a maintenance of 49.37±30.82 by the third year of follow-up (p=<0.0005). Patients with a BMI of 20-30 Kg/m² had an EWL of 60.46% during the first 6 months after surgery and an EWL of 74.84% in the first year and a maintained EWL after 3 years of 60.45%. The surgical mean time was 45 min. There were no conversions to the open approach. A 0% mortality and 1.12% morbidity were reported. The SSGS has a weight loss comparable to other restrictive procedures, with excellent mid-term excess weight loss in the 20-30 Kg/m² BMI category. This new technique is an improvement over the original technique, as it has been modified specifically to address the complications of the original non-standardized gastric plication. The benefits of this restrictive technique are that it requires no stapling, dividing, or rerouting of the intestines, as well as no need to implant a foreign body device. The disadvantages observed were a steep learning curve and lack of a standardized technique until this publication.


Assuntos
Gastroplastia/métodos , Adulto , Feminino , Gastroplastia/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Tratamentos com Preservação do Órgão , Complicações Pós-Operatórias , Estudos Prospectivos , Resultado do Tratamento , Redução de Peso
20.
J Air Waste Manag Assoc ; 65(4): 436-44, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25947213

RESUMO

UNLABELLED: This study analyzes the influence of fine particles PM2.5 on nonprogrammed children's hospital admissions that occurred in the city of Seville between 2007 and 2011, and makes an economic assessment of the cost of the children's hospital admissions for respiratory causes due to particle pollution. The PM2.5 dose-response functions for each type of hospital admission were used to quantify the cost of the hospital admissions. It can be concluded that the PM2.5 concentrations have negative effects on bronchiolitis, pneumonia, asthma, and bronchitis and other causes. A reduction of the daily average annual PM2.5 concentration from the existing levels to 10 µg/m3 would show an annual average reduction of children's hospital admissions due to respiratory diseases of 0.09 cases. This paper shows that the daily average cost for children hospital admissions due to respiratory reasons in the city of Seville, associated with daily average annual levels of PM2.5 above 10 µg/m3, was almost 200€. IMPLICATIONS: Elevated PM2.5 concentrations in Seville have negative effects on children's bronchiolitis, pneumonia, asthma, and bronchitis and other causes. A reduction of the daily average annual PM2.5 concentration from the existing levels to 10 µg/m3 would suppose an annual mean reduction of children's hospital admissions due to respiratory diseases of 0.09 cases.


Assuntos
Poluentes Atmosféricos/efeitos adversos , Hospitalização , Tamanho da Partícula , Material Particulado/efeitos adversos , Doenças Respiratórias/etiologia , Adolescente , Criança , Pré-Escolar , Humanos , Doenças Respiratórias/epidemiologia , Espanha/epidemiologia
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