121 results on '"Gonçalves IC"'
Search Results
2. IMPACT ON LEUKEMIC TRANSFORMATION OF HYPERDIPLOID KARYOTYPE IN PEDIATRIC MYELODYSPLASTIC SYNDROME
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Lima, GF, Silva, BF, Gonçalves, IC, Torres, RS, Rodrigues, EF, Lovatel, VL, and Fernandez, TS
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- 2024
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3. ASSOCIATION BETWEEN EZH2 EXPRESSION PATTERN WITH KARYOTYPE AND EVOLUTION FROM MYELODYSPLASTIC NEOPLASM TO ACUTE MYELOID LEUKEMIA
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Gonçalves, IC, Lima, GF, Silva, BF, Lovatel, VL, and Fernandez, TS
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- 2024
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4. MOLECULAR CYTOGENETIC CHARACTERIZATION OF DER(7)T(1;7) IN MYELODYSPLASTIC SYNDROME: CLINICAL IMPLICATIONS
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Lima, GF, Silva, BF, Gonçalves, IC, Otero, L, Rocha, MM, Lovatel, VL, and Fernandez, TS
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- 2024
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5. PARP inihibitor 3-aminobenzamide does not increase the yields of chromosomal aberrant cells induced by boron neutron capture reaction in V79 Chinese hamster cells
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Oliveira, NG, Castro, M, Rodrigues, AS, Gonçalves, IC, Cassapom R, Fernandes, AP, Chaveca, T, Toscano Rico, JM, Rueff, J, and Repositório da Universidade de Lisboa
- Abstract
Made available in DSpace on 2015-12-30T10:19:05Z (GMT). No. of bitstreams: 0 Previous issue date: 2001
- Published
- 2001
6. Boron neutron capture therapy (BNCT) in metastatic melanoma
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Fernandes, AP, Oliveira, NG, Castro, M, Gonçalves, IC, Ramalho, A, Rueff, J, Toscano Rico, JM, and Repositório da Universidade de Lisboa
- Abstract
Made available in DSpace on 2015-12-30T10:19:05Z (GMT). No. of bitstreams: 0 Previous issue date: 2000
- Published
- 2000
7. Genotoxic effects of boron neutron capture reaction in human melanoma cells
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Oliveira, N, Castro, M, Rodrigues, AS, Gonçalves, IC, Cassapo, R, Fernandes, AP, Vale, FM, Chaveca, T, Ramalho, AG, Toscano Rico, JM, Rueff, J, and Repositório da Universidade de Lisboa
- Abstract
Made available in DSpace on 2015-12-30T10:19:13Z (GMT). No. of bitstreams: 0 Previous issue date: 2000
- Published
- 2000
8. Embedding Bioprinting of Low Viscous, Photopolymerizable Blood-Based Bioinks in a Crystal Self-Healing Transparent Supporting Bath.
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Caiado Decarli M, Ferreira HP, Sobreiro-Almeida R, Teixeira FC, Correia TR, Babilotte J, Olijve J, Custódio CA, Gonçalves IC, Mota C, Mano JF, and Moroni L
- Abstract
Protein-based hydrogels have great potential to be used as bioinks for biofabrication-driven tissue regeneration strategies due to their innate bioactivity. Nevertheless, their use as bioinks in conventional 3D bioprinting is impaired due to their intrinsic low viscosity. Using embedding bioprinting, a liquid bioink is printed within a support that physically holds the patterned filament. Inspired by the recognized microencapsulation technique complex coacervation, crystal self-healing embedding bioprinting (CLADDING) is introduced based on a highly transparent crystal supporting bath. The suitability of distinct classes of gelatins is evaluated (i.e., molecular weight distribution, isoelectric point, and ionic content), as well as the formation of gelatin-gum arabic microparticles as a function of pH, temperature, solvent, and mass ratios. Characterizing and controlling this parametric window resulted in high yields of support bath with ideal self-healing properties for interaction with protein-based bioinks. This support bath achieved transparency, which boosted light permeation within the bath. Bioprinted constructs fully composed of platelet lysates encapsulating a co-culture of human mesenchymal stromal cells and endothelial cells are obtained, demonstrating a high-dense cellular network with excellent cell viability and stability over a month. CLADDING broadens the spectrum of photocrosslinkable materials with extremely low viscosity that can now be bioprinted with sensitive cells without any additional support., (© 2024 The Author(s). Small Methods published by Wiley‐VCH GmbH.)
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- 2024
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9. Pharmaceutical Formulations Containing Graphene and 5-Fluorouracil for Light-Emitting Diode-Based Photochemotherapy of Skin Cancer.
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Amaral SI, Silva FALS, Costa-Almeida R, Timochenco L, Fernandes JR, Sarmento B, Gonçalves IC, Magalhães FD, and Pinto AM
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- Humans, Fluorouracil pharmacology, Drug Compounding, Cell Line, Tumor, Phototherapy, Carbon, Oxides, Hydrogels pharmacology, Hydrogels chemistry, Graphite chemistry, Photochemotherapy, Skin Neoplasms drug therapy
- Abstract
Nonmelanoma skin cancer (NMSC) is the most common cancer worldwide, among which 80% is basal cell carcinoma (BCC). Current therapies' low efficacy, side effects, and high recurrence highlight the need for alternative treatments. In this work, a partially reduced nanographene oxide (p-rGOn) developed in our laboratory was used. It has been achieved through a controlled reduction of nanographene oxide via UV-C irradiation that yields small nanometric particles (below 200 nm) that preserve the original water stability while acquiring high light-to-heat conversion efficiency. The latter is explained by a loss of carbon-oxygen single bonds (C-O) and the re-establishment of sp
2 carbon bonds. p-rGOn was incorporated into a Carbopol hydrogel together with the anticancer drug 5-fluorouracil (5-FU) to evaluate a possible combined PTT and chemotherapeutic effect. Carbopol/p-rGOn/5-FU hydrogels were considered noncytotoxic toward normal skin cells (HFF-1). However, when A-431 skin cancer cells were exposed to NIR irradiation for 30 min in the presence of Carbopol/p-rGOn/5-FU hydrogels, almost complete eradication was achieved after 72 h, with a 90% reduction in cell number and 80% cell death of the remaining cells after a single treatment. NIR irradiation was performed with a light-emitting diode (LED) system, developed in our laboratory, which allows adjustment of applied light doses to achieve a safe and selective treatment, instead of the standard laser systems that are associated with damages in the healthy tissues in the tumor surroundings. Those are the first graphene-based materials containing pharmaceutical formulations developed for BCC phototherapy.- Published
- 2024
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10. Long-term in vivo degradation and biocompatibility of degradable pHEMA hydrogels containing graphene oxide.
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Moura D, Rohringer S, Ferreira HP, Pereira AT, Barrias CC, Magalhães FD, Bergmeister H, and Gonçalves IC
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- Rats, Animals, Polyhydroxyethyl Methacrylate chemistry, Hydrogels pharmacology, Hydrogels chemistry, Tissue Engineering, Inflammation, Biocompatible Materials pharmacology, Biocompatible Materials chemistry, Graphite pharmacology
- Abstract
Developing biocompatible, non-fouling and biodegradable hydrogels for blood-contacting devices remains a demanding challenge. Such materials should promote natural healing, prevent clotting, and undergo controlled degradation. This study evaluates the biocompatibility and biodegradation of degradable poly(2-hydroxyethyl methacrylate) (d-pHEMA) hydrogels with or without reinforcement with oxidized few-layer graphene (d-pHEMA/M5ox) in a long term implantation in rats, assessing non-desired side-effects (irritation, chronic toxicity, immune response). Subcutaneous implantation over 6 months revealed degradation of both hydrogels, despite slower for d-pHEMA/M5ox, with degradation products found in intracellular vesicles. No inflammation nor infection at implantation areas were observed, and no histopathological findings were detected in parenchymal organs. Immunohistochemistry confirmed d-pHEMA and d-pHEMA/M5ox highly anti-adhesiveness. Gene expression of macrophages markers revealed presence of both M1 and M2 macrophages at all timepoints. M1/M2 profile after 6 months reveals an anti-inflammatory environment, suggesting no chronic inflammation, as also demonstrated by cytokines (IL-α, TNF-α and IL-10) analysis. Overall, modification of pHEMA towards a degradable material was successfully achieved without evoking a loss of its inherent properties, specially its anti-adhesiveness and biocompatibility. Therefore, these hydrogels hold potential as blank-slate for further modifications that promote cellular adhesion/proliferation for tissue engineering applications, namely for designing blood contacting devices with different load bearing requirements. STATEMENT OF SIGNIFICANCE: Biocompatibility, tunable biodegradation kinetics, and suitable immune response with lack of chronic toxicity and irritation, are key features in degradable blood contact devices that demand long-term exposure. We herein evaluate the 6-month in vivo performance of a degradable and hemocompatible anti-adhesive hydrogel based in pHEMA, and its mechanically reinforced formulation with few-layer graphene oxide. This subcutaneous implantation in a rat model, shows gradual degradation with progressive changes in material morphology, and no evidence of local inflammation in surrounding tissue, neither signs of inflammation or adverse reactions in systemic organs, suggesting biocompatibility of degradation products. Such hydrogels exhibit great potential as a blank slate for tissue engineering applications, including for blood contact, where cues for specific cells can be incorporated., Competing Interests: Declaration of Competing Interest The authors declare that they do not possess any identifiable financial interests or personal relationships that could have potentially influenced the findings presented in this paper., (Copyright © 2023. Published by Elsevier Ltd.)
- Published
- 2024
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11. The identity of Thraulodes limbatus Navás, 1936 (Ephemeroptera: Leptophlebiidae).
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Mariano R, Gonçalves IC, and Peters J
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- 2023
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12. Poly(2-hydroxyethyl methacrylate) hydrogels containing graphene-based materials for blood-contacting applications: From soft inert to strong degradable material.
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Moura D, Pereira AT, Ferreira HP, Barrias CC, Magalhães FD, Bergmeister H, and Gonçalves IC
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- Humans, Polyhydroxyethyl Methacrylate, Endothelial Cells, Biocompatible Materials pharmacology, Water, Hydrogels pharmacology, Graphite pharmacology
- Abstract
Degradable biomaterials for blood-contacting devices (BCDs) are associated with weak mechanical properties, high molecular weight of the degradation products and poor hemocompatibility. Herein, the inert and biocompatible FDA approved poly(2-hydroxyethyl methacrylate) (pHEMA) hydrogel was turned into a degradable material by incorporation of different amounts of a hydrolytically labile crosslinking agent, pentaerythritol tetrakis(3-mercaptopropionate). In situ addition of 1wt.% of oxidized graphene-based materials (GBMs) with different lateral sizes/thicknesses (single-layer graphene oxide and oxidized forms of few-layer graphene materials) was performed to enhance the mechanical properties of hydrogels. An ultimate tensile strength increasing up to 0.2 MPa (293% higher than degradable pHEMA) was obtained using oxidized few-layer graphene with 5 μm lateral size. Moreover, the incorporation of GBMs has demonstrated to simultaneously tune the degradation time, which ranged from 2 to 4 months. Notably, these features were achieved keeping not only the intrinsic properties of inert pHEMA regarding water uptake, wettability and cytocompatibility (short and long term), but also the non-fouling behavior towards human cells, platelets and bacteria. This new pHEMA hydrogel with degradation and biomechanical performance tuned by GBMs, can therefore be envisioned for different applications in tissue engineering, particularly for BCDs where non-fouling character is essential. STATEMENT OF SIGNIFICANCE: Suitable mechanical properties, low molecular weight of the degradation products and hemocompatibility are key features in degradable blood contacting devices (BCDs), and pave the way for significant improvement in the field. In here, a hydrogel with outstanding anti-adhesiveness (pHEMA) provides hemocompatibility, the presence of a degradable crosslinker provides degradability, and incorporation of graphene oxide reestablishes its strength, allowing tuning of both degradation and mechanical properties. Notably, these hydrogels simultaneously provide suitable water uptake, wettability, cytocompatibility (short and long term), no acute inflammatory response, and non-fouling behavior towards endothelial cells, platelets and bacteria. Such results highlight the potential of these hydrogels to be envisioned for applications in tissue engineered BCDs, namely as small diameter vascular grafts., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Author(s). Published by Elsevier Ltd.. All rights reserved.)
- Published
- 2023
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13. Tailoring the Electron Trapping Effect of a Biocompatible Triboelectric Hydrogel by Graphene Oxide Incorporation towards Self-Powered Medical Electronics.
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Pereira AT, Rodrigues CRS, Silva AC, Vidal R, Ventura JO, Gonçalves IC, and Pereira AM
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- Electrons, Polyhydroxyethyl Methacrylate, Hydrogels, Electronics, Medical
- Abstract
Triboelectric nanogenerators (TENGs) are associated with several drawbacks that limit their application in the biomedical field, including toxicity, thrombogenicity, and poor performance in the presence of fluids. By proposing the use of a hemo/biocompatible hydrogel, poly(2-hydroxyethyl methacrylate) (pHEMA), this study bypasses these barriers. In contact-separation mode, using polytetrafluoroethylene (PTFE) as a reference, pHEMA generates an output of 100.0 V, under an open circuit, 4.7 μA, and 0.68 W/m
2 for an internal resistance of 10 MΩ. Our findings unveil that graphene oxide (GO) can be used to tune pHEMA's triboelectric properties in a concentration-dependent manner. At the lowest measured concentration (0.2% GO), the generated outputs increase to 194.5 V, 5.3 μA, and 1.28 W/m2 due to the observed increase in pHEMA's surface roughness, which expands the contact area. Triboelectric performance starts to decrease as GO concentration increases, plateauing at 11% volumetric, where the output is 51 V, 1.76 μA, and 0.17 W/m2 less than pHEMA's. Increases in internal resistance, from 14 ΩM to greater than 470 ΩM, ζ-potential, from -7.3 to -0.4 mV, and open-circuit characteristic charge decay periods, from 90 to 120 ms, are all observed in conjunction with this phenomenon, which points to GO function as an electron trapping site in pHEMA's matrix. All of the composites can charge a 10 μF capacitor in 200 s, producing a voltage between 0.25 and 3.5 V and allowing the operation of at least 20 LEDs. The triboelectric output was largely steady throughout the 3.33 h durability test. Voltage decreases by 38% due to contact-separation frequency, whereas current increases by 77%. In terms of pressure, it appears to have little effect on voltage but boosts current output by 42%. Finally, pHEMA and pHEMA/GO extracts were cytocompatible toward fibroblasts. According to these results, pHEMA has a significant potential to function as a biomaterial to create bio/hemocompatible TENGs and GO to precisely control its triboelectric outputs.- Published
- 2023
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14. Diagnosis of Asymptomatic Biliary Ascariasis by Abdominal Ultrasound in a Non-Endemic Area.
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Silva C, Gonçalves IC, Neves S, Ferreira DC, and Valdoleiros SR
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Biliary ascariasis is rare in non-endemic areas. This infection is associated with severe complications of the biliary tract, which can become a medical emergency. Treatment with oral anthelmintics is often effective, but, in some cases, surgery is required. We describe an unusual case of ultrasound diagnosis of biliary ascariasis in the gallbladder in a patient who, besides residing in a low-prevalence area of the infection, did not present with biliary tract manifestations. We intend to raise awareness of this clinical entity in non-endemic areas, where this diagnosis is not usually considered. A brief review of the subject is also presented., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2023, Silva et al.)
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- 2023
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15. Recurrent Respiratory Papillomatosis Presenting as Worsening Dyspnea in an HIV-infected Patient.
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Gonçalves IC, Silva C, Gomes J, and Xará S
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Recurrent respiratory papillomatosis (RRP) is a rare manifestation of human papillomavirus (HPV) infection. It is characterized by relapsing bulky papillomas in the respiratory tract, which are usually benign in nature. We describe a challenging case of RRP in an HIV-infected patient with extensive pulmonary disease, presenting with worsening dyspnea. The interaction between HPV with HIV as a coinfection is still not completely understood, particularly the role of HIV-associated immunosuppression in RRP. Our main goal is to raise awareness of this clinical entity and to promote further studies on its management, particularly in specific populations such as HIV-infected individuals. A brief review of the theme is also presented., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2022, Gonçalves et al.)
- Published
- 2022
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16. Mycobacterium marinum Cutaneous Infection: A Series of Three Cases and Literature Review.
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Gonçalves IC, Furtado I, Gonçalves MJ, and Xará S
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Mycobacterium marinum is a non-tuberculous mycobacteria present in natural and non-chlorinated bodies of water. It is a known fish pathogen but can also cause human disease. It usually causes cutaneous lesions but in rare cases may originate more invasive diseases with the involvement of deep structures. We describe three cases of patients with cutaneous infection by M. marinum evaluated in a tertiary care center, two with confirmed infection and one with a presumptive diagnosis based on clinical and epidemiological features. A brief bibliographic review of M. marinum infections is then presented to support the theme. We aim to alert one to the difficulties in establishing the correct diagnosis of this infection, emphasize the importance of a high degree of suspicion for its identification, and review the therapeutic management options., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2022, Gonçalves et al.)
- Published
- 2022
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17. Using Graphene-Based Materials for Stiff and Strong Poly(ethylene glycol) Hydrogels.
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Ferreira HP, Moura D, Pereira AT, Henriques PC, Barrias CC, Magalhães FD, and Gonçalves IC
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- Adhesives chemistry, Biocompatible Materials chemistry, Cell Line, Human Umbilical Vein Endothelial Cells, Humans, Polymers chemistry, Tissue Engineering methods, Graphite chemistry, Hydrogels chemistry, Polyethylene Glycols chemistry
- Abstract
Blood-contacting devices are increasingly important for the management of cardiovascular diseases. Poly(ethylene glycol) (PEG) hydrogels represent one of the most explored hydrogels to date. However, they are mechanically weak, which prevents their use in load-bearing biomedical applications (e.g., vascular grafts, cardiac valves). Graphene and its derivatives, which have outstanding mechanical properties, a very high specific surface area, and good compatibility with many polymer matrices, are promising candidates to solve this challenge. In this work, we propose the use of graphene-based materials as nanofillers for mechanical reinforcement of PEG hydrogels, and we obtain composites that are stiffer and stronger than, and as anti-adhesive as, neat PEG hydrogels. Results show that single-layer and few-layer graphene oxide can strengthen PEG hydrogels, increasing their stiffness up to 6-fold and their strength 14-fold upon incorporation of 4% w/v (40 mg/mL) graphene oxide. The composites are cytocompatible and remain anti-adhesive towards endothelial cells, human platelets and Staphylococcus aureus , similar to neat hydrogels. To the best of our knowledge, this is the first work to report such an increase of the tensile properties of PEG hydrogels using graphene-based materials as fillers. This work paves the way for the exploitation of PEG hydrogels as a backbone material for load-bearing applications.
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- 2022
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18. Association of deleterious sucking habits with the occurrence of otitis in newborns, infants, preschool children, and children: a systematic review protocol.
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Castro-Cunha AC, Gonçalves IC, Martins-Júnior PA, Fernandes IB, Abreu LG, Paiva SM, and Bendo CB
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- Bottle Feeding adverse effects, Child, Preschool, Fingersucking adverse effects, Habits, Humans, Infant, Infant, Newborn, Meta-Analysis as Topic, Systematic Reviews as Topic, Otitis, Sucking Behavior
- Abstract
Objective: The objective of this review is to determine whether deleterious sucking habits contribute to otitis in newborns, infants, preschool children, and children., Introduction: Otitis is one of the most prevalent diseases in infants. Diverse studies have suggested that deleterious sucking habits, such as pacifier use, bottle-feeding, and finger-sucking, may be risk factors for the development of otitis in young individuals., Inclusion Criteria: This systematic review will include observational studies in which the association between deleterious sucking habits and otitis was assessed in newborns, infants, preschool children, and children. Studies will compare caregiver reporting of sucking habits in this population to those with no deleterious sucking habits or those who exclusively breastfeed. The primary outcome will be the presence of otitis., Methods: The searches will be carried out in six electronic databases, and gray literature will also be screened. A three-step search strategy will be used, with no date or language restrictions. Studies whose full text meets the eligibility criteria will be included in the systematic review. Study screening and selection, critical appraisal, and data extraction will be performed by two independent reviewers. The Grading of Recommendations, Assessment, Development and Evaluation approach will be used to assess the certainty of the evidence. Meta-analysis will be performed if there is relative homogeneity among included studies., Systematic Review Registration Number: PROSPERO CRD42020197162., Competing Interests: The authors declare no conflict of interest., (Copyright © 2021 JBI.)
- Published
- 2021
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19. [Venomous Animals in the Portuguese Territory: Clinical Management of Bites and Stings].
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Valdoleiros SR, Gonçalves IC, Silva C, Guerra D, Silva LA, Martínez-Freiría F, Rato F, and Xará S
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- Animals, Antivenins, Portugal, Bee Venoms, Snake Bites, Spider Bites therapy
- Abstract
There are many native species of animals with the potential to cause severe disease in Portugal. Of the four clinically relevant snake species, the vipers (Vipera latastei and Vipera seoanei) are the most concerning. They can cause severe disease and require in-hospital management, monitoring and specific treatment, including the administration of anti-snake venom serum. The Malpolon monspessulanus and Macroprotodon brevis snakes cause mostly localized clinical manifestations, which do not require specific treatment. Only a minority of the spider species in Portugal possess chelicerae (mouthparts of the Chelicerata, shaped as either articulated fangs or pincers, which may contain venom or be connected to the venom glands and are used for predation or capture of food) long enough to perforate the human skin. Nevertheless, Latrodectus tredecimguttatus and Loxosceles rufescens spider bites may require specialized treatment in a hospital setting, as well as careful active symptom surveillance. Diversely, the treatment for Scolopendra cingulata and Scolopendra oraniensis centipedes' bites is merely symptomatic. The only existing scorpion species in Portugal is the Buthus ibericus; its sting typically causes local symptoms with intense pain, and its treatment consists essentially of analgesia. The insects of the Hymenoptera order, such as bees and wasps, have the ability to inject venom into the skin. Most people present only with local or regional inflammatory response, and symptomatic treatment is usually effective. Even so, individuals with hypersensitivity to bee venom may develop anaphylaxis. Several marine species in the Portuguese coast are venomous to humans, including weeverfish (Trachinidae family), stingrays (Dasyatis pastinaca, Taeniura grabata, Myliobatis aquila), red scorpion fish (Scorpaena scrofa), cnidaria (Pelagia noctiluca, Chrysaora hysoscella, Physalia physalis) and bearded fireworm (Hermodice carunculata); treatment is symptomatic. Contact with the larvae or bristles (chitinous structures with locomotor or tactile functions) of Thaumetopoea pityocampa (pine processionary) can cause cutaneous, ocular and, rarely, respiratory reactions; its management is also symptomatic.
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- 2021
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20. A novel receptor for platelet-activating factor and lysophosphatidylcholine in Trypanosoma cruzi.
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Coelho FS, Oliveira MM, Vieira DP, Torres PHM, Moreira ICF, Martins-Duarte ES, Gonçalves IC, Cabanelas A, Pascutti PG, Fragoso SP, and Lopes AH
- Subjects
- Amino Acid Sequence, Animals, Cell Differentiation, Chagas Disease parasitology, Gene Knockout Techniques methods, Host-Parasite Interactions, Humans, Lysophosphatidylcholines chemistry, Macrophages, Mice, Molecular Docking Simulation, Phylogeny, Platelet Activating Factor chemistry, Protein Conformation, Protozoan Proteins chemistry, Receptors, Adiponectin chemistry, Receptors, Adiponectin genetics, Receptors, Adiponectin metabolism, Receptors, Progesterone chemistry, Receptors, Progesterone genetics, Receptors, Progesterone metabolism, Trypanosoma cruzi chemistry, Lysophosphatidylcholines metabolism, Platelet Activating Factor metabolism, Protozoan Proteins genetics, Protozoan Proteins metabolism, Trypanosoma cruzi genetics, Trypanosoma cruzi metabolism
- Abstract
The lipid mediators, platelet-activating factor (PAF) and lysophosphatidylcholine (LPC), play relevant pathophysiological roles in Trypanosoma cruzi infection. Several species of LPC, including C18:1 LPC, which mimics the effects of PAF, are synthesized by T. cruzi. The present study identified a receptor in T. cruzi, which was predicted to bind to PAF, and found it to be homologous to members of the progestin and adiponectin family of receptors (PAQRs). We constructed a three-dimensional model of the T. cruzi PAQR (TcPAQR) and performed molecular docking to predict the interactions of the TcPAQR model with C16:0 PAF and C18:1 LPC. We knocked out T. cruzi PAQR (TcPAQR) gene and confirmed the identity of the expressed protein through immunoblotting and immunofluorescence assays using an anti-human PAQR antibody. Wild-type and knockout (KO) parasites were also used to investigate the in vitro cell differentiation and interactions with peritoneal mouse macrophages; TcPAQR KO parasites were unable to react to C16:0 PAF or C18:1 LPC. Our data are highly suggestive that PAF and LPC act through TcPAQR in T. cruzi, triggering its cellular differentiation and ability to infect macrophages., (© 2021 John Wiley & Sons Ltd.)
- Published
- 2021
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21. Graphene Oxide Coating Improves the Mechanical and Biological Properties of Decellularized Umbilical Cord Arteries.
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Pereira AT, Schneider KH, Henriques PC, Grasl C, Melo SF, Fernandes IP, Kiss H, Martins MCL, Bergmeister H, and Gonçalves IC
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- Bacterial Adhesion drug effects, Blood Platelets drug effects, Cell Adhesion drug effects, Chorion blood supply, Female, Human Umbilical Vein Endothelial Cells, Humans, Methicillin-Resistant Staphylococcus aureus drug effects, Placenta blood supply, Pregnancy, Blood Vessel Prosthesis, Coated Materials, Biocompatible chemistry, Graphite chemistry, Umbilical Arteries chemistry
- Abstract
The lack of small-diameter vascular grafts (inner diameter <5 mm) to substitute autologous grafts in arterial bypass surgeries has a massive impact on the prognosis and progression of cardiovascular diseases, the leading cause of death globally. Decellularized arteries from different sources have been proposed as an alternative, but their poor mechanical performance and high collagen exposure, which promotes platelet and bacteria adhesion, limit their successful application. In this study, these limitations were surpassed for decellularized umbilical cord arteries through the coating of their lumen with graphene oxide (GO). Placental and umbilical cord arteries were decellularized and perfused with a suspension of GO (C/O ratio 2:1) with ∼1.5 μm lateral size. A homogeneous GO coating that completely covered the collagen fibers was obtained for both arteries, with improvement of mechanical properties being achieved for umbilical cord decellularized arteries. GO coating increased the maximum force in 27%, the burst pressure in 29%, the strain in 25%, and the compliance in 10%, compared to umbilical cord decellularized arteries. The achieved theoretical burst pressure (1960 mmHg) and compliance (13.9%/100 mmHg) are similar to the human saphenous vein and mammary artery, respectively, which are used nowadays as the gold standard in coronary and peripheral artery bypass surgeries. Furthermore, and very importantly, coatings with GO did not compromise the endothelial cell adhesion but decreased platelet and bacteria adhesion to decellularized arteries, which will impact on the prevention of thrombosis and infection, until full re-endothetialization is achieved. Overall, our results reveal that GO coating has an effective role in the improvement of decellularized umbilical cord artery performance, which is a huge step toward their application as a small-diameter vascular graft.
- Published
- 2021
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22. Graphene Oxide Topical Administration: Skin Permeability Studies.
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Silva FALS, Costa-Almeida R, Timochenco L, Amaral SI, Pinto S, Gonçalves IC, Fernandes JR, Magalhães FD, Sarmento B, and Pinto AM
- Abstract
Nanostructured carriers have been widely used in pharmaceutical formulations for dermatological treatment. They offer targeted drug delivery, sustained release, improved biostability, and low toxicity, usually presenting advantages over conventional formulations. Due to its large surface area, small size and photothermal properties, graphene oxide (GO) has the potential to be used for such applications. Nanographene oxide (GOn) presented average sizes of 197.6 ± 11.8 nm, and a surface charge of -39.4 ± 1.8 mV, being stable in water for over 6 months. 55.5% of the mass of GOn dispersion (at a concentration of 1000 µg mL
-1 ) permeated the skin after 6 h of exposure. GOn dispersions have been shown to absorb near-infrared radiation, reaching temperatures up to 45.7 °C, within mild the photothermal therapy temperature range. Furthermore, GOn in amounts superior to those which could permeate the skin were shown not to affect human skin fibroblasts (HFF-1) morphology or viability, after 24 h of incubation. Due to its large size, no skin permeation was observed for graphite particles in aqueous dispersions stabilized with Pluronic P-123 (Gt-P-123). Altogether, for the first time, Gon's potential as a topic administration agent and for delivery of photothermal therapy has been demonstrated.- Published
- 2021
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23. Graphene-based materials: the key for the successful application of pHEMA as a blood-contacting device.
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Pereira AT, Henriques PC, Schneider KH, Pires AL, Pereira AM, Martins MCL, Magalhães FD, Bergmeister H, and Gonçalves IC
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- Animals, Biocompatible Materials pharmacology, Endothelial Cells, Staphylococcus aureus, Swine, Graphite, Polyhydroxyethyl Methacrylate
- Abstract
Thrombosis and infection are the leading causes of blood-contacting device (BCD) failure, mainly due to the poor performance of existing biomaterials. Poly(2-hydroxyethyl methacrylate) (pHEMA) has excellent hemocompatibility but the weak mechanical properties impair its use as a bulk material for BCD. As such, pHEMA has been explored as a coating, despite the instability and difficulty of attachment to the underlying polymer compromise its success. This work describes the hydrogel composites made of pHEMA and graphene-based materials (GBM) that meet the biological and mechanical requirements for a stand-alone BCD. Five GBM differing in thickness, oxidation degree, and lateral size were incorporated in pHEMA, revealing that only oxidized-GBM can reinforce pHEMA. pHEMA/oxidized-GBM composites are cytocompatible and prevent the adhesion of endothelial cells, blood platelets, and bacteria (S. aureus), thus maintaining pHEMA's anti-adhesive properties. As a proof of concept, the thrombogenicity of the tubular prototypes of the best formulation (pHEMA/Graphene oxide (GO)) was evaluated in vivo, using a porcine arteriovenous-shunt model. pHEMA/GO conduits withstand the blood pressure and exhibit negligible adhesion of blood components, revealing better hemocompatibility than ePTFE, a commercial material for vascular access. Our findings reveal pHEMA/GO, a synthetic and off-the-shelf hydrogel, as a preeminent material for the design of blood-contacting devices that prevent thrombosis and bacterial adhesion.
- Published
- 2021
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24. Multitask ATPases (NBDs) of bacterial ABC importers type I and their interspecies exchangeability.
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Leisico F, Godinho LM, Gonçalves IC, Silva SP, Carneiro B, Romão MJ, Santos-Silva T, and de Sá-Nogueira I
- Subjects
- ATP-Binding Cassette Transporters chemistry, Adenosine Triphosphatases genetics, Amino Acid Motifs, Bacillus subtilis chemistry, Computational Biology methods, Crystallography, X-Ray, Firmicutes chemistry, Firmicutes metabolism, Gram-Negative Bacteria chemistry, Gram-Negative Bacteria metabolism, Gram-Positive Bacteria chemistry, Gram-Positive Bacteria metabolism, Models, Molecular, Mutagenesis, Site-Directed, Protein Domains, ATP-Binding Cassette Transporters metabolism, Adenosine Triphosphatases chemistry, Adenosine Triphosphatases metabolism, Bacterial Proteins chemistry, Bacterial Proteins metabolism
- Abstract
ATP-binding cassette (ABC) type I importers are widespread in bacteria and play a crucial role in its survival and pathogenesis. They share the same modular architecture comprising two intracellular nucleotide-binding domains (NBDs), two transmembrane domains (TMDs) and a substrate-binding protein. The NBDs bind and hydrolyze ATP, thereby generating conformational changes that are coupled to the TMDs and lead to substrate translocation. A group of multitask NBDs that are able to serve as the cellular motor for multiple sugar importers was recently discovered. To understand why some ABC importers share energy-coupling components, we used the MsmX ATPase from Bacillus subtilis as a model for biological and structural studies. Here we report the first examples of functional hybrid interspecies ABC type I importers in which the NBDs could be exchanged. Furthermore, the first crystal structure of an assigned multitask NBD provides a framework to understand the molecular basis of the broader specificity of interaction with the TMDs.
- Published
- 2020
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25. Orally administrated chitosan microspheres bind Helicobacter pylori and decrease gastric infection in mice.
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Henriques PC, Costa LM, Seabra CL, Antunes B, Silva-Carvalho R, Junqueira-Neto S, Maia AF, Oliveira P, Magalhães A, Reis CA, Gartner F, Touati E, Gomes J, Costa P, Martins MCL, and Gonçalves IC
- Subjects
- Animals, Gastric Mucosa, Humans, Mice, Mice, Inbred C57BL, Microspheres, Chitosan pharmacology, Helicobacter Infections drug therapy, Helicobacter pylori
- Abstract
Persistent Helicobacter pylori (H. pylori) infection is related to 90% of gastric cancers. With bacterial resistance rising and treatment inefficiency affecting 15% of the patients, alternative treatments urge. Chitosan microspheres (ChMics) have been proposed as an H. pylori-binding system. This work evaluates ChMics biocompatibility, mucopenetration and capacity to treat H. pylori infection in mice after oral administration. ChMics of different size (XL, ∼120 µm and XS, ∼40 µm) and degree of acetylation (6% and 16%) were developed and revealed to be able to adhere both human and mouse-adapted H. pylori strains without cytotoxicity towards human gastric cells. Ex vivo studies showed that smaller (XS) microspheres penetrate further within the gastric foveolae, suggesting their ability to reach deeply adherent bacteria. In vivo assays showed 88% reduction of infection when H. pylori-infected mice (C57BL/6) were treated with more mucoadhesive XL6 and XS6 ChMics. Overall, ChMics clearly demonstrate ability to reduce H. pylori gastric infection in mice, with chitosan degree of acetylation being a dominant factor over microspheres' size on H. pylori removal efficiency. These results evidence the strong potential of this strategy as an antibiotic-free approach to fight H. pylori infection, where microspheres are orally administered, bind H. pylori in the stomach, and remove them through the gastrointestinal tract. STATEMENT OF SIGNIFICANCE: Approximately 90% of gastric cancers are caused by the carcinogenic agent Helicobacter pylori, which infects >50% of the world population. Bacterial resistance, reduced antibiotic bioavailability, and the intricate distribution of bacteria in mucus and within gastric foveolae hamper the success of most strategies to fight H. pylori. We demonstrate that an antibiotic-free therapy based on bare chitosan microspheres that bind and remove H. pylori from stomach can achieve 88% reduction of infection from H. pylori-infected mice. Changing size and mucoadhesive properties, microspheres can reach different areas of gastric mucosa: smaller and less mucoadhesive can penetrate deeper into the foveolae. This promising, simple and inexpensive strategy paves the way for a faster bench-to-bedside transition, therefore holding great potential for clinical application., Competing Interests: Declaration of Competing Interest None, (Copyright © 2020. Published by Elsevier Ltd.)
- Published
- 2020
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26. Near-Infrared Radiation-Based Mild Photohyperthermia Therapy of Non-Melanoma Skin Cancer with PEGylated Reduced Nanographene Oxide.
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Costa-Almeida R, Bogas D, Fernandes JR, Timochenco L, Silva FALS, Meneses J, Gonçalves IC, Magalhães FD, and Pinto AM
- Abstract
Using a one-step thermal reduction and non-covalent chemical functionalization process, PEGylated reduced nanographene oxide (rGOn-PEG) was produced from nanographene oxide (GOn) and characterized in terms of particle size, dispersion stability, chemistry, and photothermal properties, in view of its use for photothermal therapy (PTT) of non-melanoma skin cancer. GOn infrared spectrum presented more intense bands assigned to oxygen containing functional groups than observed for rGOn-PEG. GOn C/O ratio decreased more than 50% comparing with rGOn-PEG and nitrogen was present in the latter (N at % = 20.6) due to introduction of PEG-NH
2 . Thermogravimetric analysis allowed estimating the amount of PEG in rGOn-PEG to be of about 56.1%. Simultaneous reduction and PEGylation increased the lateral dimensions from 287 ± 139 nm to 521 ± 397 nm, as observed by transmission electron microscopy and dynamic light scattering. rGOn-PEG exhibited ≈13-fold higher absorbance in the near-infrared radiation (NIR) region, as compared to unmodified GOn. Low power (150 mW cm-2 ) NIR irradiation using LEDs resulted in rGOn-PEG heating up to 47 °C, which is within the mild PTT temperature range. PEGylation strongly enhanced the dispersibility of rGOn in physiological media (phosphate buffered saline, fetal bovine serum, and cell culture medium) and also improved the biocompatibility of rGOn-PEG, in comparison to GOn (25-250 μg mL-1 ). After a single NIR LED irradiation treatment of 30 min, a decrease of ≈38% in A-431 cells viability was observed for rGOn-PEG (250 μg mL-1 ). Together, our results demonstrate the potential of irradiating rGOn-PEG using lower energy, cheaper, smaller, and safer LEDs, as alternative to high power lasers, for NIR mild hyperthermia therapy of cancer, namely non-melanoma skin cancer.- Published
- 2020
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27. Erratum: Borges, I., et al. Exposure of Smaller and Oxidized Graphene on Polyurethane Surface Improves its Antimicrobial Performance. Nanomaterials 2020, 10 , 349.
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Borges I, Henriques PC, Gomes RN, Pinto AM, Pestana M, Magalhães FD, and Gonçalves IC
- Abstract
The authors wish to make the following corrections to this paper [...].
- Published
- 2020
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28. One less monotypic genus in Leptophlebiidae (Ephemeroptera): A new species of Bessierus Thomas amp; Orth and new record from Brazil.
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Cruz PV, GonÇalves IC, Mariano R, and Hamada N
- Subjects
- Animals, Brazil, Male, Nymph, Pigmentation, Ephemeroptera
- Abstract
A new species of Bessierus Thomas Orth, formerly a monotypic genus, is described from Amapá State, Brazil. The type species of the genus, B. doloris Thomas Orth, had only its nymphs described until recently, when its male imago was associated to nymphs mainly based on pigmentation pattern. Bessierus riobranco sp. n. here described has no significant difference on pigmentation pattern from B. doloris, thus the new species could be the male imago of B. doloris, and the putative imago of B. doloris a new species, or even both described imagoes could be new species. Still, a new male imago existence cannot be neglected and we opted to provide a properly description, diagnosis and illustration, hence contributing to the knowledge of mayfly neotropical diversity and future research on the genus. The generic concept of Bessierus and its type species diagnoses are altered to accommodate the new species, and a new record of B. doloris is provided.
- Published
- 2020
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29. Graphene Surfaces Interaction with Proteins, Bacteria, Mammalian Cells, and Blood Constituents: The Impact of Graphene Platelet Oxidation and Thickness.
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Henriques PC, Pereira AT, Pires AL, Pereira AM, Magalhães FD, and Gonçalves IC
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- Adsorption, Blood Proteins chemistry, Cell Adhesion drug effects, Cell Line, Filaggrin Proteins, Humans, Oxidation-Reduction, Surface Properties, Bacteria drug effects, Biocompatible Materials chemistry, Blood Platelets drug effects, Blood Proteins drug effects, Graphite chemistry
- Abstract
Graphene-based materials (GBMs) have been increasingly explored for biomedical applications. However, interaction between GBMs-integrating surfaces and bacteria, mammalian cells, and blood components, that is, the major biological systems in our body, is still poorly understood. In this study, we systematically explore the features of GBMs that most strongly impact the interactions of GBMs films with plasma proteins and biological systems. Films produced by vacuum filtration of GBMs with different oxidation degree and thickness depict different surface features: graphene oxide (GO) and few-layer GO (FLGO) films are more oxidized, smoother, and hydrophilic, while reduced GO (rGO) and few-layer graphene (FLG) are less or nonoxidized, rougher, and more hydrophobic. All films promote glutathione oxidation, although in a lower extent by rGO, indicating their potential to induce oxidative stress in biological systems. Human plasma proteins, which mediate most of the biological interactions, adsorb less to oxidized films than to rGO and FLG. Similarly, clinically relevant bacteria, Staphylococcus epidermidis , Staphylococcus aureus , Pseudomonas aeruginosa , and Escherichia coli , adhere less to GO and FLGO films, while rGO and FLG favor bacterial adhesion and viability. Surface features caused by the oxidation degree and thickness of the GBMs powders within the films have less influence toward human foreskin fibroblasts; all materials allow cell adhesion, proliferation and viability up to 14 days, despite less on rGO surfaces. Blood cells adhere to all films, with higher numbers in less or nonoxidized surfaces, despite none having caused hemolysis (<5%). Unlike thickness, oxidation degree of GBMs platelets strongly impact surface morphology/topography/chemistry of the films, consequently affecting protein adsorption and thus bacteria, fibroblasts and blood cells response. Overall, this study provides useful guidelines regarding the choice of the GBMs to use in the development of surfaces for an envisioned application. Oxidized materials appear as the most promising for biomedical applications that require low bacterial adhesion without being cytotoxic to mammalian cells.
- Published
- 2020
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30. Incorporation of graphene oxide into poly(ɛ-caprolactone) 3D printed fibrous scaffolds improves their antimicrobial properties.
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Melo SF, Neves SC, Pereira AT, Borges I, Granja PL, Magalhães FD, and Gonçalves IC
- Subjects
- Humans, Anti-Infective Agents chemistry, Anti-Infective Agents pharmacology, Escherichia coli growth & development, Graphite chemistry, Graphite pharmacology, Polyesters chemistry, Polyesters pharmacology, Printing, Three-Dimensional, Staphylococcus epidermidis growth & development, Tissue Scaffolds chemistry
- Abstract
Implantable medical devices infection and consequent failure is a severe health issue, which can result from bacterial adhesion, growth, and subsequent biofilm formation at the implantation site. Graphene-based materials, namely graphene oxide (GO), have been described as potential antibacterial agents when immobilized and exposed in polymeric matrices. This work focuses on the development of antibacterial and biocompatible 3D fibrous scaffolds incorporating GO. Poly(ε-caprolactone) scaffolds were produced, with and without GO, using wet-spinning combined with additive manufacturing. Scaffolds with different GO loadings were evaluated regarding physical-chemical characterization, namely GO surface exposure, antibacterial properties, and ability to promote human cells adhesion. Antimicrobial properties were evaluated through live/dead assays performed with Gram-positive and Gram-negative bacteria. 2 h and 24 h adhesion assays revealed a time-dependent bactericidal effect in the presence of GO, with death rates of adherent S. epidermidis and E. coli reaching ~80% after 24 h of contact with scaffolds with the highest GO concentration. Human fibroblasts cultured for up to 14 days were able to adhere and spread over the fibers, independently of the presence of GO. Overall, this work demonstrates the potential of GO-containing fibrous scaffolds to be used as biomaterials that hinder bacterial infection, while allowing human cells adhesion., Competing Interests: Declaration of competing interest There are no conflicts of interest to declare., (Copyright © 2019. Published by Elsevier B.V.)
- Published
- 2020
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31. A new genus of Euthyplociinae from Ecuador (Ephemeroptera: Euthyplociidae).
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GonÇalves IC, Pescador ML, and Peters JG
- Subjects
- Animals, Ecuador, Nymph, Phylogeny, Wings, Animal, Ephemeroptera
- Abstract
Three unusual nymphs of Euthyplociidae, subfamily Euthyplociinae, are described from Ecuador. A new genus and new species are established to accommodate these individuals. The morphologically unique specimens are defined by the following characters: short, stout tusks lacking spine-like setae but densely covered with long, hair-like setae; head almost as long as wide; long, quadrate clypeus with acute apicolateral projections; apex of 3rd segment of labial palp acute; apex of 3rd segment of maxillary palp acute and narrow. The hind wing is small, similar to that of Mesoplocia. An ongoing study of the phylogeny of the family recovers Dasyplocia gen. nov. as closely related to Euthyplocia and Mesoplocia.
- Published
- 2020
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32. Exposure of Smaller and Oxidized Graphene on Polyurethane Surface Improves its Antimicrobial Performance.
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Borges I, Henriques PC, Gomes RN, Pinto AM, Pestana M, Magalhães FD, and Gonçalves IC
- Abstract
Catheter-related infections are a common worldwide health problem, highlighting the need for antimicrobial catheters. Here, antibacterial potential of graphene nanoplatelets (GNP) incorporated in the commonly used polymer for catheter manufacture-polyurethane (PU)-is investigated. Two strategies are explored: melt-blending, producing a composite, and dip coating, where a composite layer is deposited on top of PU. GNP with different lateral sizes and oxidation degrees-GNP-M5, GNP-M15, GNP-M5ox, GNP-M15ox-are applied in both strategies, and the antimicrobial potential towards Staphylococcus epidermidis of GNP dispersions and GNP-containing PU evaluated. As dispersions, oxidized and smaller GNP powders (GNP-M5ox) inhibit 74% bacteria growth at 128 µg/mL. As surfaces, GNP exposure strongly impacts their antimicrobial profile: GNP absence at the surface of composites yields no significant effects on bacteria, while by varying GNP: PU ratio and GNP concentration, coatings enhance GNP exposure, depicting an antimicrobial profile. Oxidized GNP-containing coatings induce higher antibacterial effect than non-oxidized forms, particularly with smaller GNPox, where a homogeneous layer of fused platelets is formed on PU, leading to 70% reduction in bacterial adhesion and 70% bacterial death. This pioneering work unravels how to turn a polymer clinically used to produce catheters into an antimicrobial surface, crucial to reducing risk of infection associated with catheterization.
- Published
- 2020
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33. Surface Grafted MSI-78A Antimicrobial Peptide has High Potential for Gastric Infection Management.
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Parreira P, Monteiro C, Graça V, Gomes J, Maia S, Gomes P, Gonçalves IC, and Martins MCL
- Subjects
- Biocompatible Materials chemistry, Bioengineering, Helicobacter Infections microbiology, Humans, Microbial Sensitivity Tests, Nanoparticles chemistry, Proof of Concept Study, Quartz Crystal Microbalance Techniques, Staphylococcus aureus drug effects, Stomach Diseases microbiology, Antimicrobial Cationic Peptides administration & dosage, Drug Delivery Systems methods, Helicobacter Infections drug therapy, Helicobacter pylori drug effects, Stomach Diseases drug therapy
- Abstract
As we approach the end of the antibiotic era, newer therapeutic options, such as antimicrobial peptides (AMPs), are in urgent demand. AMP surface grafting onto biomaterials has been described as a good strategy to overcome problems associated with their in vivo stability. Helicobacter pylori is among the bacteria that pose greatest threat to human health, being MSI-78A one of the few bactericidal AMPs against this bacterium. Here, we report that MSI-78A grafted onto model surfaces (Self-Assembled Monolayers -SAMs), in a concentration of 30.3 ± 1.2 ng/cm
2 determined by quartz crystal microbalance with dissipation (QCM-D), was able to kill, by contact, 98% of planktonic H. pylori in only 2 h. This fact was not verified against the control bacteria (Staphylococcus epidermidis), although the minimal inhibitory concentration (MIC) of MSI-78A in solution is much lower for S. epidermidis (2 μg/mL) than for H. pylori (64 μg/mL). Our results also demonstrated that, in opposite to other bacteria, H. pylori cells were attracted to ethylene glycol terminated (antiadhesive) surfaces, which can explain the high bactericidal potential of grafted MSI-78A. This proof of concept study establishes the foundations for development of MSI-78A grafted nanoparticles for gastric infection management within a targeted nanomedicine concept.- Published
- 2019
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34. Natural infection by the protozoan Leptomonas wallacei impacts the morphology, physiology, reproduction, and lifespan of the insect Oncopeltus fasciatus.
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Vasconcellos LRC, Carvalho LMF, Silveira FAM, Gonçalves IC, Coelho FS, Talyuli OAC, Alves E Silva TL, Bastos LS, Sorgine MHF, Reis LA, Dias FA, Struchiner CJ, Gazos-Lopes F, and Lopes AH
- Subjects
- Animals, Case-Control Studies, Female, Heteroptera parasitology, Longevity, Male, Models, Theoretical, Oviposition, Population Dynamics, Sex Characteristics, Heteroptera physiology, Trypanosomatina pathogenicity
- Abstract
Trypanosomatids are protozoan parasites that infect thousands of globally dispersed hosts, potentially affecting their physiology. Several species of trypanosomatids are commonly found in phytophagous insects. Leptomonas wallacei is a gut-restricted insect trypanosomatid only retrieved from Oncopeltus fasciatus. The insects get infected by coprophagy and transovum transmission of L. wallacei cysts. The main goal of the present study was to investigate the effects of a natural infection by L. wallacei on the hemipteran insect O. fasciatus, by comparing infected and uninfected individuals in a controlled environment. The L. wallacei-infected individuals showed reduced lifespan and morphological alterations. Also, we demonstrated a higher infection burden in females than in males. The infection caused by L. wallacei reduced host reproductive fitness by negatively impacting egg load, oviposition, and eclosion, and promoting an increase in egg reabsorption. Moreover, we associated the egg reabsorption observed in infected females, with a decrease in the intersex gene expression. Finally, we suggest alterations in population dynamics induced by L. wallacei infection using a mathematical model. Collectively, our findings demonstrated that L. wallacei infection negatively affected the physiology of O. fasciatus, which suggests that L. wallacei potentially has a vast ecological impact on host population growth.
- Published
- 2019
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35. Lipid nanoparticles to counteract gastric infection without affecting gut microbiota.
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Seabra CL, Nunes C, Brás M, Gomez-Lazaro M, Reis CA, Gonçalves IC, Reis S, and Martins MCL
- Subjects
- Bacteria drug effects, Drug Carriers chemistry, Helicobacter pylori drug effects, Humans, Microbiota drug effects, Nanostructures chemistry, Particle Size, Surface-Active Agents chemistry, Anti-Bacterial Agents administration & dosage, Anti-Bacterial Agents chemistry, Gastrointestinal Microbiome drug effects, Helicobacter Infections drug therapy, Lipids chemistry, Nanoparticles administration & dosage, Nanoparticles chemistry
- Abstract
Helicobacter pylori infection is one of the major risk factors for gastric cancer development. Available antibiotic-based treatments not only fail in around 20% of patients but also have a severe negative impact on the gut microbiota. Recently, we demonstrated that nanostructured lipid carriers (NLC), even without any drug loaded, are bactericidal against H. pylori at low concentrations. This work aims to clarify NLC mode of action and to evaluate if their bactericidal effect is specific to H. pylori without affecting bacteria from microbiota. NLC were produced by hot homogenization followed by ultrasonication method, using Precirol®ATO5 and Miglyol®812 as lipids and Tween®60 as a surfactant. NLC were able to eradicate H. pylori without affecting the other tested bacteria (Lactobacillus, E. coli, S. epidermidis and S. aureus). Bioimaging assays demonstrated that NLC rapidly bind to and cross the H. pylori bacterial membrane, destabilizing and disrupting it, which leads to leakage of the cytoplasmic contents and consequent bacterial death. In an era where efficient alternatives to antibiotics are urgent, NLC are an interesting route to be explored in the quest for new antibiotic-free therapies to fight H. pylori infection., (Copyright © 2018 Elsevier B.V. All rights reserved.)
- Published
- 2018
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36. In vitro selection of Phytomonas serpens cells resistant to the calpain inhibitor MDL28170: alterations in fitness and expression of the major peptidases and efflux pumps.
- Author
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Oliveira SSC, Gonçalves IC, Ennes-Vidal V, Lopes AHCS, Menna-Barreto RFS, D'Ávila-Levy CM, Santos ALS, and Branquinha MH
- Subjects
- Calpain antagonists & inhibitors, Calpain chemistry, Calpain drug effects, Calpain genetics, Cysteine Endopeptidases immunology, Drug Resistance, Glycoproteins pharmacology, Leishmania chemistry, Leishmania physiology, Membrane Transport Proteins genetics, Peptide Hydrolases genetics, Protozoan Proteins immunology, Trypanosoma cruzi chemistry, Trypanosoma cruzi physiology, Trypanosomatina genetics, Cysteine Proteinase Inhibitors pharmacology, Dipeptides pharmacology, Membrane Transport Proteins drug effects, Peptide Hydrolases drug effects, Trypanosomatina drug effects
- Abstract
The species Phytomonas serpens is known to express some molecules displaying similarity to those described in trypanosomatids pathogenic to humans, such as peptidases from Trypanosoma cruzi (cruzipain) and Leishmania spp. (gp63). In this work, a population of P. serpens resistant to the calpain inhibitor MDL28170 at 70 µ m (MDLR population) was selected by culturing promastigotes in increasing concentrations of the drug. The only relevant ultrastructural difference between wild-type (WT) and MDLR promastigotes was the presence of microvesicles within the flagellar pocket of the latter. MDLR population also showed an increased reactivity to anti-cruzipain antibody as well as a higher papain-like proteolytic activity, while the expression of calpain-like molecules cross-reactive to anti-Dm-calpain (from Drosophila melanogaster) antibody and calcium-dependent cysteine peptidase activity were decreased. Gp63-like molecules also presented a diminished expression in MDLR population, which is probably correlated to the reduction in the parasite adhesion to the salivary glands of the insect vector Oncopeltus fasciatus. A lower accumulation of Rhodamine 123 was detected in MDLR cells when compared with the WT population, a phenotype that was reversed when MDLR cells were treated with cyclosporin A and verapamil. Collectively, our results may help in the understanding of the roles of calpain inhibitors in trypanosomatids.
- Published
- 2018
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37. Tempol improves lipid profile and prevents left ventricular hypertrophy in LDL receptor gene knockout (LDLr-/-) mice on a high-fat diet.
- Author
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Viana Gonçalves IC, Cerdeira CD, Poletti Camara E, Dias Garcia JA, Ribeiro Pereira Lima Brigagão M, Bessa Veloso Silva R, and Bitencourt Dos Santos G
- Subjects
- Animals, Lipids blood, Male, Mice, Mice, Inbred C57BL, Mice, Knockout, Receptors, LDL genetics, Spin Labels, Cyclic N-Oxides pharmacology, Cyclic N-Oxides therapeutic use, Diet, High-Fat, Hypertrophy, Left Ventricular prevention & control, Lipid Metabolism drug effects
- Abstract
Introduction and Objective: Dyslipidemia is associated with increased risk of cardiovascular disease and atherosclerosis, and hence with high morbidity and mortality. This study investigated the effects of the nitroxide 4-hydroxy-2,2,6,6-tetramethylpiperidine 1-oxyl (Tempol) on lipid profile and cardiac morphology in low-density lipoprotein (LDL) receptor gene knockout (LDLr-/-) mice., Methods: Male LDLr-/- mice (three months old, approximately 22 g weight) were divided into the following groups: controls, including (1) standard chow (SC, n=8) and (2) high-fat diet (HFD, n=8); and treatment, including (3) standard chow + Tempol (SC+T, n=8) (30 mg/kg administered by gavage, once daily) and (4) high-fat diet + Tempol (HFD+T, n=8) (30 mg/kg). After 30 days of the diet/treatment, whole blood was collected for analysis of biochemical parameters (total cholesterol, triglycerides [TG], high-density lipoprotein [HDL], LDL, and very low-density lipoprotein [VLDL]). The heart was removed through thoracotomy and histological analysis of the left ventricle was performed., Results: A significant increase in TG, LDL, and VLDL and marked left ventricular hypertrophy (LVH) were demonstrated in the HFD group relative to the SC group (p<0.05), while Tempol treatment (HFD+T group) significantly (p<0.05) prevented increases in the levels of these lipid profile markers and attenuated LVH compared with the HFD group., Conclusion: In this study, Tempol showed potential for the prevention of events related to serious diseases of the cardiovascular system., (Copyright © 2017 Sociedade Portuguesa de Cardiologia. Publicado por Elsevier España, S.L.U. All rights reserved.)
- Published
- 2017
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38. Poly(lactic acid) Composites Containing Carbon-Based Nanomaterials: A Review.
- Author
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Gonçalves C, Gonçalves IC, Magalhães FD, and Pinto AM
- Abstract
Poly(lactic acid) (PLA) is a green alternative to petrochemical commodity plastics, used in packaging, agricultural products, disposable materials, textiles, and automotive composites. It is also approved by regulatory authorities for several biomedical applications. However, for some uses it is required that some of its properties be improved, namely in terms of thermo-mechanical and electrical performance. The incorporation of nanofillers is a common approach to attain this goal. The outstanding properties of carbon-based nanomaterials (CBN) have caused a surge in research works dealing with PLA/CBN composites. The available information is compiled and reviewed, focusing on PLA/CNT (carbon nanotubes) and PLA/GBM (graphene-based materials) composites. The production methods, and the effects of CBN loading on PLA properties, namely mechanical, thermal, electrical, and biological, are discussed.
- Published
- 2017
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39. Docosahexaenoic acid loaded lipid nanoparticles with bactericidal activity against Helicobacter pylori.
- Author
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Seabra CL, Nunes C, Gomez-Lazaro M, Correia M, Machado JC, Gonçalves IC, Reis CA, Reis S, and Martins MCL
- Subjects
- Cell Line, Tumor, Drug Carriers chemistry, Fish Oils chemistry, Helicobacter Infections drug therapy, Humans, Nanostructures chemistry, Particle Size, Polysorbates chemistry, Stomach microbiology, Surface-Active Agents chemistry, Anti-Bacterial Agents chemistry, Anti-Bacterial Agents pharmacology, Docosahexaenoic Acids chemistry, Docosahexaenoic Acids pharmacology, Helicobacter pylori drug effects, Lipids chemistry, Nanoparticles chemistry
- Abstract
Docosahexaenoic acid (DHA), an omega-3 polyunsaturated fatty acid present in fish oil, has been described as a promising molecule to the treatment of Helicobacter pylori gastric infection. However, due to its highly unsaturated structure, DHA can be easily oxidized loosing part of its bioactivity. This work aims the nanoencapsulation of DHA to improve its bactericidal efficacy against H. pylori. DHA was loaded into nanostructured lipid carriers (NLC) produced by hot homogenization and ultrasonication using a blend of lipids (Precirol ATO5
® , Miglyol-812® ) and a surfactant (Tween 60® ). Homogeneous NLC with 302±14nm diameter, -28±3mV surface charge (dynamic and electrophoretic light scattering) and containing 66±7% DHA (UV/VIS spectroscopy) were successfully produced. Bacterial growth curves, performed over 24h in the presence of different DHA concentrations (free or loaded into NLC), demonstrated that nanoencapsulation enhanced DHA bactericidal effect, since DHA-loaded NLC were able to inhibit H. pylori growth in a much lower concentrations (25μM) than free DHA (>100μM). Bioimaging studies, using scanning and transmission electron microscopy and also imaging flow cytometry, demonstrated that DHA-loaded NLC interact with H. pylori membrane, increasing their periplasmic space and disrupting membrane and allowing the leakage of cytoplasmic content. Furthermore, the developed nanoparticles are not cytotoxic to human gastric adenocarcinoma cells at bactericidal concentrations. DHA-loaded NLC should, therefore, be envisaged as an alternative to the current treatments for H. pylori infection., (Copyright © 2017 Elsevier B.V. All rights reserved.)- Published
- 2017
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40. [Proposal for an epidemiological observatory in the Brazilian Unified National Health System].
- Author
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Saldanha RF, Bastos RR, Bustamante-Teixeira MT, Leite IC, and Campos EM
- Subjects
- Brazil, Decision Making, Humans, Information Storage and Retrieval methods, Internet, Information Systems instrumentation, Medical Informatics instrumentation, Systems Integration, User-Computer Interface
- Abstract
Following the creation of the Brazilian Unified National Health System (SUS), the Brazilian Health Informatics Department (DATASUS) was established in 1991, aimed at organizing information systems and databases in health. Online data access and viewing is free and open, using tables and graphs of aggregate data and access to raw data. However, the current form of data access does not fully meet the demands by health system administrators and other users for a flexible, user-friendly tool that allows dealing with various relevant health issues in the knowledge search and decision-making. We propose an ancillary system capable of generating monthly summary reports that are easy to access and understand, with an emphasis on viewing information through graphs and maps.
- Published
- 2017
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41. Susceptibility of Phytomonas serpens to calpain inhibitors in vitro: interference on the proliferation, ultrastructure, cysteine peptidase expression and interaction with the invertebrate host.
- Author
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Oliveira SS, Gonçalves DS, Garcia-Gomes AD, Gonçalves IC, Seabra SH, Menna-Barreto RF, Lopes AH, D'Avila-Levy CM, Santos AL, and Branquinha MH
- Subjects
- Animals, Blotting, Western, Cysteine metabolism, Dipeptides, Euglenozoa enzymology, Euglenozoa ultrastructure, Flow Cytometry, Lethal Dose 50, Microscopy, Electron, Salivary Glands parasitology, Cysteine drug effects, Euglenozoa drug effects, Heteroptera parasitology, Host-Parasite Interactions physiology
- Abstract
A pleiotropic response to the calpain inhibitor MDL28170 was detected in the tomato parasite Phytomonas serpens. Ultrastructural studies revealed that MDL28170 caused mitochondrial swelling, shortening of flagellum and disruption of trans Golgi network. This effect was correlated to the inhibition in processing of cruzipain-like molecules, which presented an increase in expression paralleled by decreased proteolytic activity. Concomitantly, a calcium-dependent cysteine peptidase was detected in the parasite extract, the activity of which was repressed by pre-incubation of parasites with MDL28170. Flow cytometry and Western blotting analyses revealed the differential expression of calpain-like proteins (CALPs) in response to the pre-incubation of parasites with the MDL28170, and confocal fluorescence microscopy confirmed their surface location. The interaction of promastigotes with explanted salivary glands of the insect Oncopeltus fasciatus was reduced when parasites were pre-treated with MDL28170, which was correlated to reduced levels of surface cruzipain-like and gp63-like molecules. Treatment of parasites with anti-Drosophila melanogaster (Dm) calpain antibody also decreased the adhesion process. Additionally, parasites recovered from the interaction process presented higher levels of surface cruzipain-like and gp63-like molecules, with similar levels of CALPs cross-reactive to anti-Dm-calpain antibody. The results confirm the importance of exploring the use of calpain inhibitors in studying parasites' physiology.
- Published
- 2017
- Full Text
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42. A new species of Polyplocia Lestage from Malaysia with comments on the genus (Ephemeroptera, Euthyplociidae, Euthyplociinae).
- Author
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Gonçalves IC and Peters JG
- Subjects
- Animals, Color, Ephemeroptera anatomy & histology, Female, Malaysia, Male, Nymph, Ovum, Wings, Animal, Ephemeroptera classification
- Abstract
Polyplocia nebulosa sp. nov. is described based on male and female imagos from Malaysia, Sabah State. Nymphs provisionally assigned to this species are also described. This species can be readily separated from P. vitalisi by the color pattern of the wings, with light brown longitudinal veins, narrow dark brown clouds on cross veins and margins of wings tinged with brown. The male genitalia are distinct from those of other species of Polyplocia: penes are broad, T-shaped, with large lateral projecting lobes, which are apically rounded, and with a small dorsolateral spine on each lobe; the styliger plate is short and not projected posteriorly. Eggs of the genus are described for the first time using scanning electron microscopy. Eggs are 265-267 µm in length, 170-186 µm in width, barrel-shaped, without polar caps or other attachment structures, with one visible micropyle and with chorion forming an irregular mesh with raised ridges (mesh between 3.8-8 µm). A key to male adults of Polyplocia is provided and additional records of Polyplocia from Thailand are given.
- Published
- 2016
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- View/download PDF
43. Polymer surface adsorption as a strategy to improve the biocompatibility of graphene nanoplatelets.
- Author
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Pinto AM, Moreira JA, Magalhães FD, and Gonçalves IC
- Subjects
- Adsorption, Cells, Cultured, Fibroblasts cytology, Hemolysis, Humans, Polyvinyl Alcohol, Surface Properties, Biocompatible Materials chemistry, Cell Proliferation, Fibroblasts chemistry, Graphite chemistry, Nanostructures chemistry, Polymers chemistry
- Abstract
The biointeractions of graphene-based materials depend on their physico-chemical properties. These properties can be manipulated by polymer adsorption. Graphene nanoplatelets (GNP-C) were modified with PVA, HEC, PEG, PVP, chondroitin, glucosamine, and hyaluronic acid. These materials were characterized by SEM, DLS, XPS, Raman spectroscopy, and TGA. Surface adsorption was confirmed for all polymers. Biocompatibility evaluation showed that all of these materials induced low haemolysis (<1.7%) at concentrations up to 500μgmL(-1). GNP-C-PVA and GNP-C-HEC presented the lowest haemolysis percentages and were therefore more thoroughly studied. The morphology of HFF-1 cells was investigated by microscopy (optical, fluorescence, TEM) in order to evaluate interactions with GNP materials. Small GNP-C nanoplatelets were observed to enter cells independently of the surface treatment. For pristine GNP-C at a concentration of 50μgmL(-1), ROS production increased 4.4-fold. This effect is lower for GNP-C-PVA (3.3-fold) and higher for GNP-C-HEC (5.1-fold). Resazurin assays showed that GNP-C caused toxicity in HFF-1 cells at concentrations above 20μgmL(-1) at 24h, which decreased at 48 and 72h. PVA surface adsorption rendered GNP-C non-toxic at concentrations up to 50μgmL(-1). LIVE/DEAD assays showed that at 20 and 50μgmL(-1) cell death is significantly lower for GNP-C-PVA compared to pristine GNP-C. Modification of nanoplatelets with HEC resulted in no benefit in terms of biocompatibility, whereas PVA considerably improved the biocompatibility., (Copyright © 2016 Elsevier B.V. All rights reserved.)
- Published
- 2016
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44. Aquatic Insects from the Caatinga: checklists and diversity assessments of Ubajara (Ceará State) and Sete Cidades (Piauí State) National Parks, Northeastern Brazil.
- Author
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Takiya DM, Santos AP, Pinto ÂP, Henriques-Oliveira AL, Carvalho Ado L, Sampaio BH, Clarkson B, Moreira FF, Avelino-Capistrano F, Gonçalves IC, Cordeiro Ida R, Câmara JT, Barbosa JF, de Souza WR, and Rafael JA
- Abstract
Background: Diversity and distribution of Neotropical aquatic insects is still poorly known, with many species to be recorded and many others to be described, due to the small number of taxonomists and sparse faunistic studies. This knowledge is especially poor in the Caatinga Domain in Northeastern Brazil, even though, this region may have played an important historical role in the spatial evolution of faunas of forested areas in northern South America., New Information: Aquatic insect checklists of 96 species from Parque Nacional de Ubajara (Ceará State, Brazil) and 112 species from Parque Nacional de Sete Cidades (Piauí State, Brazil) are presented, representing the following taxa: Elmidae, Epimetopidae, Hydrophilidae, and Torridincolidae (Coleoptera), Hemerodromiinae (Diptera: Empididae), Ephemeroptera, Gerromorpha and Nepomorpha (Hemiptera), Odonata, Plecoptera, and Trichoptera. Because of the scarce number of biological inventories in Northeastern Brazil, several new distributional records (of species, genera, and families) for Brazil, Northeastern Brazil, and Ceará and Piauí states are provided. In addition, several undescribed species were detected, being 26 from Ubajara and 20 from Sete Cidades. Results represent a significant increase to the known fauna of these states, ranging from 13%-70% increase for Ceará and 41% to 91% increase for Piauí. Although both parks are relatively close to each other and within the Caatinga domain, their aquatic fauna display a very high complementarity (89% species), possibly due to structural differences of water bodies sampled in each park. Rarefaction curves based on quantitative light trap samples suggest a much higher expected species richness of aquatic insects at Sete Cidades than at Ubajara National Park. Discussion on biogeographical affinities of this sample of the Caatinga fauna is provided.
- Published
- 2016
- Full Text
- View/download PDF
45. [Opportunistic screening versus missed opportunities: non-adherence to Pap smear testing in women attending prenatal care].
- Author
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Ribeiro L, Bastos RR, Vieira Mde T, Ribeiro LC, Teixeira MT, and Leite IC
- Subjects
- Adolescent, Adult, Age Factors, Brazil, Cross-Sectional Studies, Female, Humans, Pregnancy, Prenatal Care, Socioeconomic Factors, Surveys and Questionnaires, Young Adult, Papanicolaou Test statistics & numerical data, Patient Acceptance of Health Care statistics & numerical data, Uterine Cervical Neoplasms prevention & control, Vaginal Smears statistics & numerical data
- Abstract
The objectives were to estimate the prevalence of non-adherence to Pap smear testing in women attending prenatal care and to identify associated factors. This was a cross-sectional population-based study in 308 women from a rural municipality (county) in Minas Gerais State, Brazil. Complex stratified cluster sampling was used. Statistical analysis used the chi-square test and logistic regression model with the variables that presented p-value ≤ 0.05 in the bivariate model. Prevalence of lack of Pap smear test was 21.3%. Among women 25 years or older, prevalence was 15.1%. Non-adherence was more common in young, single women and those with low schooling. Low schooling remained associated with non-performance of Pap smear (OR = 0.41), indicating that women with more schooling enjoyed higher odds of testing. Contact with the prenatal clinic did not determine guaranteed access to the test, thus indicating missed opportunities when opportunistic screening is employed.
- Published
- 2016
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46. Sexual function of women surviving cervical cancer.
- Author
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Corrêa CS, Leite IC, Andrade AP, de Souza Sérgio Ferreira A, Carvalho SM, and Guerra MR
- Subjects
- Adult, Aged, Case-Control Studies, Female, Humans, Middle Aged, Surveys and Questionnaires, Uterine Cervical Neoplasms therapy, Quality of Life, Sexual Behavior, Sexual Dysfunction, Physiological, Sexual Dysfunctions, Psychological, Survivors psychology, Uterine Cervical Neoplasms psychology
- Abstract
Objective: The objective of this study was to evaluate the sexual function of survivors of cervical cancer (CC) in comparison to the control group of women without a history of cancer., Methods: This was an observational, analytical, case-control study. In the cancer group, women subjected to CC treatment of at least 3 months in the past were included (n = 37). For each survivor, one random selection from a base population control group was made (n = 37) of a woman without a history of cancer and with similar socioeconomic and demographic characteristics. The sexual function was evaluated through the female sex function index (FSFI) instrument. Data collection occurred through the application of questions in a face-to-face interview., Results: In the cancer group, 64.9 % related vaginal stenosis or shortening; 59.5 % were not sexually active and of those which had sexual relations, 80 % showed dysfunction. The total FSFI score varied between 9.60 and 35.10 in the cancer group and 23.90 and 36.00 in the control group. The means of the cancer group were statistically inferior (P < 0.05) to the control group in all the FSFI domains and in the total score. The mean total score was 21.72 in the cancer group, classified as sexual dysfunction when considering a score of 26 as the cutoff point., Conclusion: CC treatment was found to have a negative impact on the sexual function of women. Further, sexual function should be monitored routinely by interdisciplinary teams to provide comprehensive care with the objective of an improved quality of life post-cancer.
- Published
- 2016
- Full Text
- View/download PDF
47. Bacteria-targeted biomaterials: Glycan-coated microspheres to bind Helicobacter pylori.
- Author
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Gonçalves IC, Magalhães A, Costa AM, Oliveira JR, Henriques PC, Gomes P, Reis CA, and Martins MC
- Subjects
- Animals, Bacterial Adhesion drug effects, Cell Death drug effects, Cell Line, Tumor, Fluorescein-5-isothiocyanate metabolism, Helicobacter pylori drug effects, Humans, Mice, Inbred C57BL, Polysaccharides ultrastructure, Spectroscopy, Fourier Transform Infrared, Stomach drug effects, Stomach microbiology, Coated Materials, Biocompatible pharmacology, Helicobacter pylori physiology, Microspheres, Polysaccharides pharmacology
- Abstract
Gastric cancer is the third leading cause of cancer related deaths worldwide and Helicobacter pylori (H. pylori) persistent infection has been pointed as a causative agent of this disease. Current antibiotic based treatments to eradicate this bacterium fail in 20% of the patients, potentially leaving 140 million people in the world without alternative therapy. It is herein proposed the use of azide-alkyne coupling ("click chemistry") to produce glycan-coated mucoadhesive microspheres that bind and remove the H. pylori adherent to the gastric mucosa through specific bacterial adhesin-glycan interactions. Glycan immobilization is performed via chitosan's primary alcohol group, rather than the more reactive primary amines in order to preserve the amine groups that confer chitosan its mucoadhesiveness. It is shown that chitosan microspheres decorated with Lewis b glycans (Leb-Mic) bind specifically to H. pylori strains expressing the BabA adhesin (strains recognized as highly pathogenic) (∼230 bacteria/microsphere), are non-cytotoxic, are retained in the stomach of C57BL/6 mice for around 1.5h. Also, these Leb-Mic are able to prevent and remove H. pylori adhesion to gastric mucosa expressing the same glycan, in tissue sections from mice and human gastric mucosa (in vitro) and in fresh mice stomachs (ex vivo). These results provide proof-of-concept on the potential of glycan-decorated microspheres as an innovative therapeutic strategy against H. pylori and highlight the prospective of using targeted biomaterials to fight gastrointestinal infection., Statement of Significance: Gastric cancer has been associated with persistent infection by Helicobacter pylori, a bacterium that colonizes half of world population and whose available antibiotic treatment fails in 20% of cases. H. pylori adhesion to gastric epithelium is mediated between bacterial adhesins and glycans expressed in gastric mucosa. We demonstrate that these glycans can be immobilized in a controlled orientation into mucoadhesive chitosan microspheres, making them selective for different H. pylori strains. Efficacy studies (in vitro and ex vivo) with mice and human gastric mucosa that express the same glycan, revealed microspheres capacity to remove/prevent specific H. pylori adhesion, envisaging their future application as bacteria scavenging from stomach. This bacteria-binding strategy can be extrapolated to target other cells/bacteria using suitable ligands., (Copyright © 2016 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.)
- Published
- 2016
- Full Text
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48. Two new species of Ulmeritoides Traver (Ephemeroptera: Leptophlebiidae) from Southeastern Brazil.
- Author
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Souto PM, Da-Sil ER, Nessimian JL, and Gonçalves IC
- Subjects
- Animal Distribution, Animal Structures anatomy & histology, Animal Structures growth & development, Animals, Body Size, Brazil, Ecosystem, Ephemeroptera anatomy & histology, Ephemeroptera growth & development, Female, Male, Organ Size, Wings, Animal anatomy & histology, Wings, Animal growth & development, Ephemeroptera classification
- Abstract
Two new species of Ulmeritoides Traver, 1959 are described from Southeastern Brazil based on male and female imagos. Ulmeritoides angelus sp. nov. (Holotype male deposited in DZRJ: Minas Gerais State) differs from all other species of the genus by the following combination of characters: forewings hyaline, base dark brown and purplish; veins R1 light brown; dark brown spots on bullae of veins Sc and R2; apex of penis lobes somewhat rounded, each with one central spine. Ulmeritoides tamoio sp. nov. (Holotype male deposited in DZRJ: São Paulo State) differs from all other species of the genus by the following combination of characters: wings hyaline; veins C, Sc and R1 brownish; brownish spots on bullae of veins Sc and R2; apex of penis lobes straight, ending in rather acute apical and mesal projections. An updated key to the genera Ulmeritoides Traver, 1956 and Ulmeritus Traver, 1956 is also given.
- Published
- 2016
- Full Text
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49. [Patient satisfaction evaluation at the Specialized Dental Centers in the Southeast Macro-region of Minas Gerais, Brazil, 2013].
- Author
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Kitamura ES, Bastos RR, Palma PV, and Leite IC
- Subjects
- Adult, Aged, Aged, 80 and over, Brazil, Cross-Sectional Studies, Dental Care statistics & numerical data, Female, Health Care Surveys, Humans, Male, Middle Aged, Needs Assessment, Young Adult, Dental Care psychology, Dental Health Services, Patient Satisfaction statistics & numerical data
- Abstract
Methods: this was a cross-sectional study using the Oral Health Services Quality Assessment Questionnaire, with a probabilistic sample of 256 patients, using multiple linear regression to identify variables associated with their satisfaction., Results: most patients stated they were satisfied (86.7%), followed by barely satisfied (10.2%) and very satisfied (3.1%); there were differences in satisfaction among patients attending the different SDCs; independent variables associated with patient satisfaction were 'improved self-perceived oral health' (p=0.001) and less 'waiting time at the clinic' (p<0.001)., Conclusion: he majority of patients were satisfied with the service provided; variables not analyzed in this study, including infrastructure, human resources and management, may have influenced the differences in patient satisfaction found between the different SDCs.
- Published
- 2016
- Full Text
- View/download PDF
50. ANALYSIS ON QUALITY OF LIFE OF PATIENTS WITH OSTEOARTHROSIS UNDERGOING TOTAL HIP ARTHROPLASTY.
- Author
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de Araújo Loures E and Leite IC
- Abstract
Objective: The aim of the study was to evaluate the health-related quality of life among patients affected by hip osteoarthrosis who were treated by means of total hip arthroplasty., Methods: A cohort of 38 patients operated by a single surgeon in a regional referential teaching hospital during the year 2010 was prospectively studied and followed up for at least six months until they had achieved satisfactory rehabilitation. Each patient gave responses to the SF-36 form immediately before the operation and six months later and the Harris Hip Score was obtained at the same time. The pre and postoperative results were analyzed and compared with the literature., Results: The pre and postoperative SF-36 results were as follows: physical function: 13.4-53.7; role physical: 9.21-48.0; body pain: 23.1-62.6; general health: 54.2-71.3; vitality: 40.3-69.9; social function: 40.8-74.3; role emotional: 23.7-64.9; and mental health: 52.6-80.4. The Harris Hip Score went from 36.1 to 92.1, on average. All the results were statistically significant (p < 0.001)., Conclusions: The combination of two scales was shown to be valuable in identifying bias and gave greater reliability for understanding the different variables. The study showed that there was a significant improvement in health-related quality of life among patients affected by osteoarthrosis of different etiologies who underwent total hip arthroplasty. Health-related quality of life evaluations cannot replace clinical evaluations provided by specific instruments and physicians' experience but can add important data through giving value to patients' sets of expectations regarding medical treatment. Moreover, such evaluations can be considered to be an efficient tool for analyzing the outcomes from total hip arthroplasty.
- Published
- 2015
- Full Text
- View/download PDF
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