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1.
Cureus ; 16(6): e62240, 2024 Jun.
Article in English | MEDLINE | ID: mdl-39006601

ABSTRACT

Immune checkpoint inhibitors (ICIs) have completely changed cancer treatment in the last decade and are now widely used in several cancers. In the era of immunotherapy, oncologists have changed not only the way they evaluate treatment efficacy but also the management of treatment-related adverse events. This new profile of immune adverse events has resulted in an urgent need for a more holistic view of cancer patients and for more collaborations with other organ specialists to optimize patient treatment and support. The anti-programmed death-ligand 1 antibody, avelumab, has been widely used as a maintenance treatment in stage IV urothelial carcinoma since the results from the Javelin 100 bladder trial were published. We report a case of a 75-year-old man with stage IV urothelial carcinoma submitted to first-line platinum-based chemotherapy followed by maintenance avelumab. He achieved a complete bone and pulmonary response 10 months after stopping avelumab, which was suspended due to a serious immune adverse event, an ICI-induced type 1 diabetes mellitus. At present, the patient has an overall survival of 24 months and shows no evidence of disease with a good quality of life 16 months after avelumab suspension. We hypothesized that a late response to avelumab could explain this unexpected outcome.

2.
Front Psychol ; 15: 1253356, 2024.
Article in English | MEDLINE | ID: mdl-38646129

ABSTRACT

The rise of feminist and LGBTQIA+ movements paved the way for many equality reforms. These include language reforms, which facilitate inclusion of multiple groups in society. For example, the shift from the generic "he" to "he or she" and "they" allows for the inclusion of women, transgender, and non-binary individuals in many narratives. For this reason, many institutions worldwide encourage neutral language. It remains unclear how individuals interpret neutral language. One case of neutral language is the pronoun "they," which has been assigned multiple definitions from the 1970s to 2022. We examine how the pronoun "they" has been interpreted, used, and accepted over time. We discuss trends in the findings and make suggestions for future research directions, including the need for better methods to investigate pronouns and clarification on what the focus of neutral language should be. This timely commentary has implications for action on equality, diversity, and inclusion.

3.
Commun Biol ; 6(1): 108, 2023 01 27.
Article in English | MEDLINE | ID: mdl-36707645

ABSTRACT

The steep increase in nontuberculous mycobacteria (NTM) infections makes understanding their unique physiology an urgent health priority. NTM synthesize two polysaccharides proposed to modulate fatty acid metabolism: the ubiquitous 6-O-methylglucose lipopolysaccharide, and the 3-O-methylmannose polysaccharide (MMP) so far detected in rapidly growing mycobacteria. The recent identification of a unique MMP methyltransferase implicated the adjacent genes in MMP biosynthesis. We report a wide distribution of this gene cluster in NTM, including slowly growing mycobacteria such as Mycobacterium avium, which we reveal to produce MMP. Using a combination of MMP purification and chemoenzymatic syntheses of intermediates, we identified the biosynthetic mechanism of MMP, relying on two enzymes that we characterized biochemically and structurally: a previously undescribed α-endomannosidase that hydrolyses MMP into defined-sized mannoligosaccharides that prime the elongation of new daughter MMP chains by a rare α-(1→4)-mannosyltransferase. Therefore, MMP biogenesis occurs through a partially conservative replication mechanism, whose disruption affected mycobacterial growth rate at low temperature.


Subject(s)
Mycobacterium , Mycobacterium/genetics , Lipopolysaccharides , Mannosyltransferases , Methyltransferases
4.
RSC Adv ; 12(53): 34414-34424, 2022 Nov 29.
Article in English | MEDLINE | ID: mdl-36545629

ABSTRACT

Temporary tattoos and dyes are increasing popularity as an alternative to permanent ones. However, knowledge on its elementary composition is scarce and, this scientific gap can potentially make them a source of heavy metal exposure on humans. The present research aimed to explore the possibility of using the inorganic chemical signature to characterize natural pigments-based products and to evaluate the heavy metal content in jagua temporary tattoos and henna temporary hair dyes and tattoos. Thirty-four different samples of commercial products were analyzed for the presence and quantity of eleven trace elements (Al, Cr, Mn, Co, Ni, Cu, Zn, As, Cd, Ba, and Pb) by inductively coupled plasma mass spectrometry (ICP-MS). The overall mean concentrations varied between 0.02 and 973 µg g-1 in solid samples or 0.01-1878 µg g-1 for paste ones, wherein potential fake products were uncovered. None of the 34 samples considered comply with the current European Cosmetics Regulation. Samples were differentiated according to their Cr, Zn, Ba, and Pb content. The overall results revealed highly variable levels in the investigated samples, which leads us to suggest detailed quality controls of these materials, due the fact that their continued use can origin potential threat to human health.

5.
Anal Bioanal Chem ; 414(20): 6233-6246, 2022 Aug.
Article in English | MEDLINE | ID: mdl-35829771

ABSTRACT

Temporary tattoos and dyes constitute a great analytical challenge in relation to the regulatory control of their ingredients. Most of these commercial products are not labeled according to their content and their chemical nature is highly diverse. Therefore, it is necessary to analyze these complex samples to evaluate the potential presence of metallic impurities, to ensure the safety of cosmetic products contributing to health protection. This study proposes a multi-analytical methodology, which includes handheld X-ray fluorescence (h-XRF) and X-ray diffraction (XRD), complemented by variable pressure scanning electron microscopy coupled with energy-dispersive X-ray spectrometry (VP-SEM-EDS) to fully characterize 34 commercial samples of jagua and henna tattoos and dyes. The approach allowed the identification of the main constituents providing complementary compositional data and differences between sample types were established. In addition, information on the degree of natural pigments homogeneity was also obtained. The results' discussion considering the current European cosmetics regulation may be useful to support the drafting of safety requirements and specific regulation.


Subject(s)
Cosmetics , Tattooing , Coloring Agents , Microscopy, Electron, Scanning , Spectrometry, X-Ray Emission
6.
Article in English | MEDLINE | ID: mdl-35020578

ABSTRACT

The ubiquitous occurrence of mycotoxins in the environment results in unavoidable and repeated human exposure to mixtures of mycotoxins, the main exposure being through the consumption of contaminated foods, such as cereals and milk. Considering the frequency of contamination of these foods with mycotoxins, this study aimed to evaluate the risk of exposure to aflatoxins, ochratoxin A, deoxynivalenol and zearalenone in a Portuguese population under 17 years old through the consumption of these foods. To assess mycotoxin exposure, food contamination data was provided by the Official National Plan to Control Food and the food consumption information from the National Food, Nutrition, and Physical Activity Survey of the Portuguese General Population (2015-2016); risk assessment calculations were performed through the Monte Carlo probabilistic method. In view of the results obtained for aflatoxins, ochratoxin A, deoxynivalenol and zearalenone, and considering the legislation in force, the levels observed were below the maximum levels. However, there was a risk in deoxynivalenol exposure for children from 0 to 9 years old (average and high consumers), and for high consumers from 10 to 17 years old. Given the potential adverse effects of these mycotoxins, their co-existence in the same foods and being a priority issue defined by the European Food Safety Authority, tight control should be carried out, in addition to re-evaluation of the maximum levels of these mycotoxins.


Subject(s)
Aflatoxins , Mycotoxins , Zearalenone , Aflatoxins/analysis , Animals , Cattle , Edible Grain/chemistry , Female , Food Contamination/analysis , Humans , Milk/chemistry , Mycotoxins/analysis , Portugal
7.
Vaccine ; 39 Suppl 1: A56-A69, 2021 03 15.
Article in English | MEDLINE | ID: mdl-33509695

ABSTRACT

OBJECTIVE: The objective of this study was to estimate the public health and economic benefits (from a Medicare perspective) of Fluzone High-Dose® in the US elderly population, since its introduction in 2010. METHODS: A budget impact model was developed using a decision tree framework and applied over 9 influenza seasons (2010/11 to 2018/19). The decision tree model was designed to capture influenza cases, hospitalizations possibly related to influenza or laboratory confirmed influenza, and influenza-related deaths. The analysis included influenza vaccines recommended by ACIP since 2010: SD TIV (trivalent), SD QIV (quadrivalent), HD TIV, aTIV (adjuvanted), ccQIV (cell-cultured). Two strategies were compared to evaluate the impact of HD TIV: a 'with HD TIV' strategy representative of the US vaccine landscape, and a 'without HD TIV' where the absence of HD TIV was modelled. Clinical and economic inputs were based on public US data from the CDC and national databases, while data on vaccine effectiveness were extracted from published literature and clinical trials. The impact of HD TIV was further explored in five scenario analyses and deterministic sensitivity analyses (DSA). RESULTS: Over 10 years, it is estimated that HD TIV resulted in an averted 1,333,479 influenza cases, 769,476 medical visits, 40,004 ED presentations, 520,342 cardiorespiratory hospitalizations and 73,689 deaths and generated an absolute $4.6 billion in savings, translating into a return on investment of 214.4%. Hospitalizations costs represented 98.4% and 98.3% of the management costs in the 'with HD TIV' strategy and 'without HD TIV' strategy respectively. Hospitalizations and HD TIV relative vaccine efficacy vs SD TIV as a major cost driver were further confirmed in scenario analysis and DSA. HD TIV remained cost saving under all the scenarios. CONCLUSION: The model showed that HD TIV higher efficacy translated into increased averted health and economic outcomes. HD TIV represented a cost saving intervention from a payer perspective since its introduction.


Subject(s)
Influenza Vaccines , Influenza, Human , Aged , Cost-Benefit Analysis , Humans , Influenza, Human/epidemiology , Influenza, Human/prevention & control , Medicare , Public Health , United States/epidemiology
8.
J Oral Implantol ; 47(1): 9-17, 2021 Feb 01.
Article in English | MEDLINE | ID: mdl-32663305

ABSTRACT

The aim of this study was to characterize the mechanical properties of a bioactive-modified polyetheretherketone (PEEK) manufacturing approach for dental implants and to compare the in vitro biological behavior with titanium alloy (Ti6Al4V) as the reference. PEEK, PEEK with 5% hydroxyapatite (HA), PEEK with 5% beta-tricalcium phosphate (ßTCP), and Ti6Al4V discs were produced using hot pressing technology to create a functionally graded material (FGM). Surface roughness values (Ra, Rz), water contact angle, shear bond strength, and Vickers hardness tests were performed. Human osteoblasts and gingival fibroblasts bioactivity was evaluated by a resazurin-based method, alkaline phosphatase activity (ALP), and confocal laser scanning microscopy (CLSM) images of fluorescent-stained fibroblasts. Morphology and cellular adhesion were confirmed using field emission gun-scanning electron microscopy (FEG-SEM). Group comparisons were tested using analysis of variance (Tukey post hoc test), α = .05. All groups presented similar roughness values (P > .05). Ti6Al4V group was found to have the highest contact angle (P < .05). Shear bond strength and Vickers hardness of different PEEK materials were similar (P > .05); however, the mean values in the Ti6Al4V group were significantly higher when compared with those of the other groups (P < .05). Cell viability and proliferation of osteoblast and fibroblast cells were higher in the PEEK group (P < .05). PEEK-ßTCP showed the highest significant ALP activity over time (P < .05 at 14 days of culture). An enhanced bone and soft-tissue cell behavior on pure PEEK was obtained to the gold standard (Ti6Al4V) with equivalent roughness. The results substantiate the potential role of chemical composition rather than physical properties of materials in biological responses. The addition of 5% HA or ßTCP by FGM did not enhance PEEK mechanical properties or periodontal cell behavior.


Subject(s)
Dental Implants , Benzophenones , Humans , Ketones , Polyethylene Glycols , Polymers , Surface Properties , Titanium
9.
J Appl Oral Sci ; 28: e20200100, 2020.
Article in English | MEDLINE | ID: mdl-32667382

ABSTRACT

Adding a biological apatite layer to the implant surface enhances bone healing around the implant. Objective This study aimed to characterize the mechanical properties and test human gingival fibroblasts behavior in contact with Zirconia and Titanium bioactive-modified implant materials. Methodology 6 groups were considered: Titanium (Ti6Al4V), Ti6Al4V with 5% HA and 5% ßTCP, Zirconia (YTZP), YTZP with 5% HA and 5% ßTCP. For each group, we produced discs using a novel fabrication method for functionally graded materials, under adequate conditions for etching and grit-blasting to achieve equivalent surface microroughness among the samples. Surface roughness (Ra, Rz), water contact angle, shear bond strength, and Vickers hardness were performed. Human gingival fibroblasts immortalized by hTERT gene from the fourth passage, were seeded on discs for 14 days. Cell viability and proliferation were assessed using a resazurin-based method, and cellular adhesion and morphology using field emission gun scanning electron microscopy (FEG-SEM). After 3 days of culture, images of fluorescent nucleic acid stain were collected by confocal laser scanning microscopy (CLSM). Results Results were presented as mean ± standard deviation (SD). We compared groups using one-way ANOVA with Tukey's post-hoc test, and significance level was set at p<0.05. After 14 days of culture, cell viability and proliferation were significantly higher in YTZP group than in other groups (p<0.05). Samples of YTZP-ßTCP presented significantly higher wettability (p<0.05); yet, we observed no improvement in cell behavior on this group. Fibroblast spreading and surface density were more evident on YTZP specimens. Adding calcium-phosphate bioactive did not alter the tested mechanical properties; however, Ti6Al4V material shear bond strength was statistically higher than other groups (p<0.05). Conclusion Adding bioactive materials did not improve soft-tissue cell behavior. When compared to other zirconia and titanium groups, pure zirconia surface improved adhesion, viability and proliferation of fibroblasts. Cell behavior seems to depend on surface chemical composition rather than on surface roughness.


Subject(s)
Dental Implants , Fibroblasts , Titanium , Zirconium , Humans , Microscopy, Electron, Scanning , Surface Properties
10.
Primates ; 61(3): 357-363, 2020 May.
Article in English | MEDLINE | ID: mdl-32318929

ABSTRACT

The West-African sooty mangabey (Cercocebus atys) is threatened by habitat loss, hunting for meat consumption, and mortality during crop-foraging events. The species' overall demographic trend is unknown. Presence and distribution in Guinea-Bissau, a country neighbored by Senegal and Republic of Guinea, was confirmed in 1946 but the species was declared extinct in 1989 and not observed in subsequent countrywide expeditions. Narratives of its presence across southern Guinea-Bissau are scattered in reports and occurrence in the eastern part was reported in 2017, but the limits of its distribution are currently unknown. Here, we present recent geo-referenced visual and molecular-based records of the sooty mangabey for three protected areas in southern Guinea-Bissau collected as part of a region-wide survey. Individuals were observed in Cufada Lagoons Natural Park (2015) and Dulombi National Park (NP) (2016) and photographed in Boé NP (2007, 2015 and 2020). Thirty-six samples collected in Boé NP (2017) were identified as sooty mangabey using a 402 base pair fragment of the mitochondrial cytochrome b gene. Our work suggests a wider distribution in Guinea-Bissau than previously described, augments knowledge of the populations' current habitat use and threats, and has implications for efforts to conserve the species in West Africa. Considering the sooty mangabey as the reservoir of the simian immunodeficiency virus that led to the human variant, HIV-2, confirmation that the Guinea-Bissau population is not extinct may lead to a better understanding of early viral jump to humans and consequent epidemic spread, specifically of the HIV-2 Subgroup A. We highlight the need for extra conservation measures by Guinea-Bissau authorities.


Subject(s)
Animal Distribution , Cercocebus atys , Conservation of Natural Resources , Animals , Feces/chemistry , Guinea-Bissau , Photography
11.
Microbiology (Reading) ; 166(5): 474-483, 2020 05.
Article in English | MEDLINE | ID: mdl-32100712

ABSTRACT

Mycobacterium hassiacum is so far the most thermophilic among mycobacteria as it grows optimally at 50 °C and up to 65 °C in a glycerol-based medium, as verified in this study. Since this and other nontuberculous mycobacteria (NTM) thrive in diverse natural and artificial environments, from where they may access and infect humans, we deemed essential to probe M. hassiacum resistance to heat, a strategy routinely used to control microbial growth in water-supply systems, as well as in the food and drink industries. In addition to possibly being a threat in its own right in rare occasions, M. hassiacum is also a good surrogate for studying other NTM species more often associated with opportunistic infection, namely Mycobacterium avium and Mycobacterium abscessus as well as their strictly pathogenic counterparts Mycobacterium tuberculosis and Mycobacterium leprae. In this regard, this thermophilic species is likely to be useful as a source of stable proteins that may provide more detailed structures of potential drug targets. Here, we investigate M. hassiacum growth at near-pasteurization temperatures and at different pHs and also characterize its thermostable glucosyl-3-phosphoglycerate synthase (GpgS), an enzyme considered essential for M. tuberculosis growth and associated with both nitrogen starvation and thermal stress in different NTM species.


Subject(s)
Bacterial Proteins/metabolism , Glucosyltransferases/metabolism , Mycobacteriaceae/growth & development , Mycobacteriaceae/genetics , Bacterial Proteins/genetics , DNA, Bacterial/genetics , Glucosyltransferases/genetics , Hydrogen-Ion Concentration , Mycobacteriaceae/metabolism , Nontuberculous Mycobacteria/genetics , Nontuberculous Mycobacteria/growth & development , Nontuberculous Mycobacteria/metabolism , Pasteurization , Temperature
12.
J. appl. oral sci ; 28: e20200100, 2020. tab, graf
Article in English | LILACS, BBO - Dentistry | ID: biblio-1134773

ABSTRACT

Abstract Adding a biological apatite layer to the implant surface enhances bone healing around the implant. Objective This study aimed to characterize the mechanical properties and test human gingival fibroblasts behavior in contact with Zirconia and Titanium bioactive-modified implant materials. Methodology 6 groups were considered: Titanium (Ti6Al4V), Ti6Al4V with 5% HA and 5% ßTCP, Zirconia (YTZP), YTZP with 5% HA and 5% ßTCP. For each group, we produced discs using a novel fabrication method for functionally graded materials, under adequate conditions for etching and grit-blasting to achieve equivalent surface microroughness among the samples. Surface roughness (Ra, Rz), water contact angle, shear bond strength, and Vickers hardness were performed. Human gingival fibroblasts immortalized by hTERT gene from the fourth passage, were seeded on discs for 14 days. Cell viability and proliferation were assessed using a resazurin-based method, and cellular adhesion and morphology using field emission gun scanning electron microscopy (FEG-SEM). After 3 days of culture, images of fluorescent nucleic acid stain were collected by confocal laser scanning microscopy (CLSM). Results Results were presented as mean ± standard deviation (SD). We compared groups using one-way ANOVA with Tukey's post-hoc test, and significance level was set at p<0.05. After 14 days of culture, cell viability and proliferation were significantly higher in YTZP group than in other groups (p<0.05). Samples of YTZP-ßTCP presented significantly higher wettability (p<0.05); yet, we observed no improvement in cell behavior on this group. Fibroblast spreading and surface density were more evident on YTZP specimens. Adding calcium-phosphate bioactive did not alter the tested mechanical properties; however, Ti6Al4V material shear bond strength was statistically higher than other groups (p<0.05). Conclusion Adding bioactive materials did not improve soft-tissue cell behavior. When compared to other zirconia and titanium groups, pure zirconia surface improved adhesion, viability and proliferation of fibroblasts. Cell behavior seems to depend on surface chemical composition rather than on surface roughness.


Subject(s)
Humans , Titanium , Zirconium , Dental Implants , Fibroblasts , Surface Properties , Microscopy, Electron, Scanning
13.
Microsc Microanal ; 25(1): 214-220, 2019 02.
Article in English | MEDLINE | ID: mdl-30702056

ABSTRACT

Five scarabs and one scaraboid found in Vinha das Caliças 4 (Beja, Portugal) were analyzed using a micro-analytical methodology in order to determine their mineralogical and chemical composition. Microstructural characterization and chemical analysis revealed that all were composed of a white body of crushed feldspathic sand covered by a lead-rich, alkaline-depleted silicate blue-green glaze showing evident signs of glass deterioration. Variable pressure scanning electron microscopy with X-ray energy dispersive spectrometry, handheld X-ray fluorescence spectroscopy, and micro X-ray diffraction results show that blue-green color of the glaze was produced by using copper ions (Cu2+) in conjunction with the lead antimonate bindheimite, a yellow-colored opacifier. The introduction of small amounts of tin in the structure of bindheimite enabled the production of a ternary Pb-Sb-Sn oxide. Tin, which was most likely added with the copper source (bronze scrapings), is known to facilitate the crystallization of bindheimite. The results are consistent with the five scarabs and one scaraboid being manufactured in Egypt. This study, the first archeometric study of scarabs found in the Iberian peninsula, has greatly contributed to the understanding of the influence of the Eastern and Central Mediterranean world in the Southwestern Iberia during the first millennium B.C.

14.
Proc Natl Acad Sci U S A ; 116(3): 835-844, 2019 01 15.
Article in English | MEDLINE | ID: mdl-30606802

ABSTRACT

Mycobacteria are a wide group of organisms that includes strict pathogens, such as Mycobacterium tuberculosis, as well as environmental species known as nontuberculous mycobacteria (NTM), some of which-namely Mycobacterium avium-are important opportunistic pathogens. In addition to a distinctive cell envelope mediating critical interactions with the host immune system and largely responsible for their formidable resistance to antimicrobials, mycobacteria synthesize rare intracellular polymethylated polysaccharides implicated in the modulation of fatty acid metabolism, thus critical players in cell envelope assembly. These are the 6-O-methylglucose lipopolysaccharides (MGLP) ubiquitously detected across the Mycobacterium genus, and the 3-O-methylmannose polysaccharides (MMP) identified only in NTM. The polymethylated nature of these polysaccharides renders the intervening methyltransferases essential for their optimal function. Although the knowledge of MGLP biogenesis is greater than that of MMP biosynthesis, the methyltransferases of both pathways remain uncharacterized. Here, we report the identification and characterization of a unique S-adenosyl-l-methionine-dependent sugar 1-O-methyltransferase (MeT1) from Mycobacterium hassiacum that specifically blocks the 1-OH position of 3,3'-di-O-methyl-4α-mannobiose, a probable early precursor of MMP, which we chemically synthesized. The high-resolution 3D structure of MeT1 in complex with its exhausted cofactor, S-adenosyl-l-homocysteine, together with mutagenesis studies and molecular docking simulations, unveiled the enzyme's reaction mechanism. The functional and structural properties of this unique sugar methyltransferase further our knowledge of MMP biosynthesis and provide important tools to dissect the role of MMP in NTM physiology and resilience.


Subject(s)
Methylmannosides/metabolism , Methyltransferases/metabolism , Mycobacterium/metabolism , Polysaccharides, Bacterial/biosynthesis , Catalytic Domain , Methyltransferases/genetics , Multigene Family , Mycobacterium/genetics
15.
Int J Oral Maxillofac Implants ; 34(1): 39­46, 2019.
Article in English | MEDLINE | ID: mdl-30282086

ABSTRACT

PURPOSE: The aim of this study was to characterize and compare the behavior of human osteoblasts and human gingival fibroblasts in contact with polyetheretherketone (PEEK), zirconia, and titanium implant surface materials. MATERIALS AND METHODS: PEEK, yttria-stabilized zirconia (YTZP), and titanium discs were produced under appropriate and similar conditions to achieve controlled surface features. Human osteoblasts and human gingival fibroblasts were cultured on discs for 14 days. Cell viability and proliferation were evaluated using a resazurin-based method. Morphology and cellular adhesion were observed using field emission gun-scanning electron microscopy (FEG-SEM). Alkaline phosphatase (ALP) activity and bone cell mineralization were evaluated on osteoblasts. Confocal laser scanning microscopy (CLSM) images of fluorescent-stained fibroblasts were obtained at 7 and 14 days of the culture. Results were presented as mean and standard deviation (SD). Group comparisons were tested using analysis of variance (ANOVA) (Tukey's post hoc) with appropriate statistical software, and significance was set at P < .05. RESULTS: Cell viability and proliferation were higher in PEEK and YTZP groups compared with titanium on osteoblast cells (P < .05, all time points) and on fibroblasts (P < .05, 7 and 14 days). All groups showed an increase in ALP activity over time, which was not significant. Mineralization patterns demonstrated an increase in mineral content over time, which was more apparent in the YTZP group. Cell spreading was more evident on PEEK and YTZP specimens. CONCLUSION: The results suggest increased adhesion, viability, and proliferation of osteoblasts and gingival fibroblasts on zirconia and PEEK surfaces compared with titanium. These results are correlated with the increased wettability of these materials.


Subject(s)
Dental Materials , Fibroblasts/physiology , Ketones , Osteoblasts/physiology , Polyethylene Glycols , Titanium , Zirconium , Analysis of Variance , Benzophenones , Cell Adhesion , Cell Proliferation , Cell Survival , Cells, Cultured , Fibroblasts/cytology , Gingiva/cytology , Humans , Microscopy, Electron, Scanning , Osteoblasts/cytology , Polymers , Surface Properties
16.
J Biomed Mater Res A ; 106(7): 1923-1931, 2018 07.
Article in English | MEDLINE | ID: mdl-29575452

ABSTRACT

The aim of this study was to analyze the osteogenic cell behavior on the surface of novel functionally graded titanium-based composites containing bioactive ceramics. Titanium grade V discs (8 × 3 mm) embedding gradual content of hydroxyapatite (TiAlV-HA) or beta-tricalcium phosphate (TiAlV-ßTCP) were produced by hot-pressing technique. Titanium-ceramic composite discs and Ti grade V (control group) were placed in contact with human osteoblast culture assays. The morphology and adhesion of osteoblasts were inspected by field emission guns scanning electron microscopy (FEGSEM) while cell viability was assessed by fluorometric method. Alkaline phosphatase (ALP) activity and fluorescent microscopic analyses were used to evaluate mineralization on the test and control discs. FEGSEM images showed cells adhered to Ti6Al4V-ceramic and Ti6Al4V surfaces over a period of 24 h, and therefore, an intense proliferation of osteoblasts and spreading cells was noticed for 7 days. Cell viability increased with time on all the surfaces although TiAlV-ßTCP revealed significant higher percentage of cell viability than that recorded for TiAlV-HA (p < 0.01). TiAlV-ßTCP also showed the highest hydrophilic character. ALP levels increased on the Ti6Al4V-ceramic surfaces when compared to the control group. Also, a qualitative analysis of mineralization evidenced an increase in mineral content on TiAlV-HA or TiAlV-ßTCP groups. Novel functionally graded composites based on Ti grade V and hydroxyapatite or ßTCP showed a higher bioactivity in presence of osteoblasts than that recorded on Ti grade V. Also, such functionally graded materials can prevent risks of failures by detachment of bioactive ceramic materials during implant placement. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 1923-1931, 2018.


Subject(s)
Biocompatible Materials/pharmacology , Ceramics/pharmacology , Osteoblasts/cytology , Titanium/pharmacology , Alkaline Phosphatase/metabolism , Alloys , Calcification, Physiologic/drug effects , Cell Proliferation/drug effects , Cell Shape/drug effects , Cell Survival/drug effects , Cells, Cultured , Fluorescence , Hardness , Humans , Osteoblasts/drug effects , Osteoblasts/metabolism , Water
17.
Glycobiology ; 27(3): 213-227, 2017 03 04.
Article in English | MEDLINE | ID: mdl-28025249

ABSTRACT

Despite the progressive decline in tuberculosis mortality, strains resistant to our dated antibiotics remain a global threat, as are the emerging nontuberculous mycobacteria, ubiquitous in natural and human environments. This pressing situation boosted by debilitated immune systems, chronic illness and the aged population calls for efficient strategies to fight these successful organisms, and identifying pathways critical for their survival is a crucial step towards this goal. In this context, the glycoside glucosylglycerate (GG) has been implicated in the adaptation of mycobacteria to nitrogen starvation and to thermal stress, and the key gene for GG synthesis has been considered essential for Mycobacterium tuberculosis growth. The many organisms we now know to have genes for GG metabolism opened new exciting avenues of research into its functions, hinting for example at hypothetical roles as an inter-cellular messenger among bacteria and in microbe-plant interactions, or at key roles in the global nitrogen cycle beyond what cyanobacteria and mycobacteria have taught us so far. Indeed, the insights into GG biology gained over the last decade have changed the perception of GG from a rare polysaccharide constituent to a widespread molecule with multiple functions and biosynthetic origins. It is now possible to build upon this knowledge and further explore its physiological importance in both pathogenic and environmentally relevant microorganisms. In particular, the vital roles of GG and of its important derivative the mycobacterial methylglucose lipopolysaccharide (MGLP) discussed here are now evident, making their metabolic links attractive targets for the development of new urgently needed antimycobacterial therapies.


Subject(s)
Glucosides/metabolism , Glycosides/metabolism , Lipopolysaccharides/metabolism , Tuberculosis/metabolism , Anti-Bacterial Agents/therapeutic use , Drug Resistance, Bacterial/genetics , Glucosides/biosynthesis , Glycosides/biosynthesis , Glycosides/genetics , Humans , Mycobacterium tuberculosis/drug effects , Mycobacterium tuberculosis/pathogenicity , Nitrogen/metabolism , Polysaccharides, Bacterial/metabolism , Tuberculosis/drug therapy , Tuberculosis/genetics , Tuberculosis/microbiology
18.
Microbes Infect ; 18(4): 290-3, 2016 Apr.
Article in English | MEDLINE | ID: mdl-26655883

ABSTRACT

Streptococcus dysgalactiae subsp. dysgalactiae (SDSD) are considered exclusive animal pathogens; however, a putative zoonotic upper limb cellulitis, a prosthetic joint infection and an infective endocarditis were described in humans. To unravel if bovine SDSD isolates are able to infect human cells, the adherence and internalization to human primary keratinocytes of two bovine SDSD strains isolated from milk collected from udder were analyzed. Bacterial adhesion assays and confocal microscopy indicate a high adherence and internalization of SDSD isolates to human cells, suggesting for the first time the ability of bovine isolates to infect human cells.


Subject(s)
Keratinocytes/microbiology , Milk/microbiology , Streptococcus/pathogenicity , Animals , Bacterial Adhesion , Cattle , Cells, Cultured , Endocytosis , Humans , Mammary Glands, Animal/microbiology , Microscopy, Confocal , Streptococcus/isolation & purification
19.
Front Genet ; 6: 314, 2015.
Article in English | MEDLINE | ID: mdl-26539210

ABSTRACT

Livestock conservation practice is changing rapidly in light of policy developments, climate change and diversifying market demands. The last decade has seen a step change in technology and analytical approaches available to define, manage and conserve Farm Animal Genomic Resources (FAnGR). However, these rapid changes pose challenges for FAnGR conservation in terms of technological continuity, analytical capacity and integrative methodologies needed to fully exploit new, multidimensional data. The final conference of the ESF Genomic Resources program aimed to address these interdisciplinary problems in an attempt to contribute to the agenda for research and policy development directions during the coming decade. By 2020, according to the Convention on Biodiversity's Aichi Target 13, signatories should ensure that "…the genetic diversity of …farmed and domesticated animals and of wild relatives …is maintained, and strategies have been developed and implemented for minimizing genetic erosion and safeguarding their genetic diversity." However, the real extent of genetic erosion is very difficult to measure using current data. Therefore, this challenging target demands better coverage, understanding and utilization of genomic and environmental data, the development of optimized ways to integrate these data with social and other sciences and policy analysis to enable more flexible, evidence-based models to underpin FAnGR conservation. At the conference, we attempted to identify the most important problems for effective livestock genomic resource conservation during the next decade. Twenty priority questions were identified that could be broadly categorized into challenges related to methodology, analytical approaches, data management and conservation. It should be acknowledged here that while the focus of our meeting was predominantly around genetics, genomics and animal science, many of the practical challenges facing conservation of genomic resources are societal in origin and are predicated on the value (e.g., socio-economic and cultural) of these resources to farmers, rural communities and society as a whole. The overall conclusion is that despite the fact that the livestock sector has been relatively well-organized in the application of genetic methodologies to date, there is still a large gap between the current state-of-the-art in the use of tools to characterize genomic resources and its application to many non-commercial and local breeds, hampering the consistent utilization of genetic and genomic data as indicators of genetic erosion and diversity. The livestock genomic sector therefore needs to make a concerted effort in the coming decade to enable to the democratization of the powerful tools that are now at its disposal, and to ensure that they are applied in the context of breed conservation as well as development.

20.
Biotechnol Bioeng ; 112(6): 1210-9, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25765286

ABSTRACT

The use of microfluidics platforms combined with the optimal optical properties of gold nanoparticles has found plenty of application in molecular biosensing. This paper describes a bio-microfluidic platform coupled to a non-cross-linking colorimetric gold nanoprobe assay to detect a single nucleotide polymorphism associated with increased risk of obesity fat-mass and obesity-associated (FTO) rs9939609 (Carlos et al., 2014). The system enabled significant discrimination between positive and negative assays using a target DNA concentration of 5 ng/µL below the limit of detection of the conventionally used microplate reader (i.e., 15 ng/µL) with 10 times lower solution volume (i.e., 3 µL). A set of optimization of our previously reported bio-microfluidic platform (Bernacka-Wojcik et al., 2013) resulted in a 160% improvement of colorimetric analysis results. Incorporation of planar microlenses increased 6 times signal-to-loss ratio reaching the output optical fiber improving by 34% the colorimetric analysis of gold nanoparticles, while the implementation of an optoelectronic acquisition system yielded increased accuracy and reduced noise. The microfluidic chip was also integrated with a miniature fiber spectrometer to analyze the assays' colorimetric changes and also the LEDs transmission spectra when illuminating through various solutions. Furthermore, by coupling an optical microscope to a digital camera with a long exposure time (30 s), we could visualise the different scatter intensities of gold nanoparticles within channels following salt addition. These intensities correlate well to the expected difference in aggregation between FTO positive (none to small aggregates) and negative samples (large aggregates).


Subject(s)
Biosensing Techniques/methods , DNA Probes , Gold , Microfluidics/methods , Nanotechnology/methods , Polymorphism, Single Nucleotide , Colorimetry/methods , Genetic Predisposition to Disease , Humans , Obesity/genetics , Optical Imaging/methods , Spectrum Analysis/methods
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