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1.
Nature ; 551(7679): 187-191, 2017 11 09.
Article in English | MEDLINE | ID: mdl-29088701

ABSTRACT

Forest edges influence more than half of the world's forests and contribute to worldwide declines in biodiversity and ecosystem functions. However, predicting these declines is challenging in heterogeneous fragmented landscapes. Here we assembled a global dataset on species responses to fragmentation and developed a statistical approach for quantifying edge impacts in heterogeneous landscapes to quantify edge-determined changes in abundance of 1,673 vertebrate species. We show that the abundances of 85% of species are affected, either positively or negatively, by forest edges. Species that live in the centre of the forest (forest core), that were more likely to be listed as threatened by the International Union for Conservation of Nature (IUCN), reached peak abundances only at sites farther than 200-400 m from sharp high-contrast forest edges. Smaller-bodied amphibians, larger reptiles and medium-sized non-volant mammals experienced a larger reduction in suitable habitat than other forest-core species. Our results highlight the pervasive ability of forest edges to restructure ecological communities on a global scale.


Subject(s)
Biodiversity , Forests , Amphibians/anatomy & histology , Animals , Birds/anatomy & histology , Body Size , Geographic Mapping , Mammals/anatomy & histology , Population Dynamics , Reptiles/anatomy & histology
2.
Reumatismo ; 75(4)2023 Dec 19.
Article in English | MEDLINE | ID: mdl-38115779

ABSTRACT

Lumbar pain is a very common symptom that derives from benign musculoskeletal conditions, rheumatic inflammatory diseases, neoplasms, and referred and/or nociplastic pain. A 70-year-old man with psoriatic arthritis presented with early-onset lumbosacral pain without evident red flags. Symptomatic treatment was unhelpful. Radiographic imaging showed subtle signs of a disease that could easily be missed. Magnetic resonance imaging revealed a massive prostatic malignancy with bone (sacral and iliopubic) metastasis. Awareness must be given not to disregard every lumbar pain as part of the preexisting rheumatic inflammatory disease (spondyloarthropathy in this case) or a common muscle/ligament/articular disarrangement. Persistence of pain, albeit not inflam-matory nor sharp in nature, despite adequate treatment might be just as important as an acute red flag and requires proper follow-up.


Subject(s)
Arthritis, Psoriatic , Low Back Pain , Musculoskeletal Diseases , Rheumatic Diseases , Male , Humans , Aged , Arthritis, Psoriatic/complications , Lumbosacral Region , Rheumatic Diseases/complications
3.
Lett Appl Microbiol ; 71(3): 259-271, 2020 Sep.
Article in English | MEDLINE | ID: mdl-32412089

ABSTRACT

We evaluated the activity of the aqueous fraction and the ethyl acetate fraction of Stryphnodendron adstringens against Staphylococcus aureus and proposed their mechanism of action. The antibacterial activity of S. adstringens fractions was evaluated against S. aureus and the cell targets were rated by docking. The fractions showed moderate antibacterial activity against S. aureus without toxicity on two mammalian cell lines. They also showed synergistic antibacterial activity with tannic acid (TA). In silico assays indicated FabG, FabZ and FabI as probable targets. The metabolic pathway for fatty acid biosynthesis in S. aureus was affected by components of S. adstringens. The synergistic effect when combining TA with S. adstringens fractions suggests a natural alternative to S. aureus control. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first study describing the possible targets of action of Stryphnodendron adstringens on Staphylococcus aureus. Molecular dynamics simulations showed that the components of S. adstringens affected the metabolic pathway for fatty acid biosynthesis (FAS II) in S. aureus, inhibiting the FabI, FabG and FabZ enzymes. As tannic acid (TA) is a known inhibitor of some targets identified, we showed synergistic antibacterial activity of S. adstringens in combination with TA. This combination did not show toxicity against HaCaT and Vero cells and based on all these results we suggest that S. adstringens can be a natural and sustainable alternative to S. aureus control.


Subject(s)
Anti-Bacterial Agents/pharmacology , Fabaceae/chemistry , Fatty Acid Synthase, Type II/antagonists & inhibitors , Plant Extracts/pharmacology , Staphylococcus aureus/drug effects , Animals , Anti-Bacterial Agents/adverse effects , Cell Line , Chlorocebus aethiops , Computer Simulation , Fatty Acids/biosynthesis , Microbial Sensitivity Tests , Molecular Dynamics Simulation , Plant Extracts/adverse effects , Tannins/pharmacology , Vero Cells
4.
Rev Sci Tech ; 39(2): 481-490, 2020 Aug.
Article in English | MEDLINE | ID: mdl-33046927

ABSTRACT

Climate change is predicted to change the nature and distribution of global farming systems, and strategies will be needed to adapt and optimise global food-producing systems. If genomic technologies are to be useful in this scenario, there is a need for the careful definition of phenotypes and routine sample collection, as well as large-scale genotyping of animal populations. Genomic tools will greatly enhance the characterisation of available germplasm and exploration of local genetic resources, while faster and cheaper DNA sequencing is leading to an increased understanding of the underlying genetic basis of traits. The use of genomic tools to increase animal resilience, reduce methane emissions from cattle and sheep, improve disease resistance, decrease environmental impact, reduce competition for land and water and, finally, increase production may be the most feasible path for the future of livestock production. In this review, the authors discuss various genomic strategies in the light of climate change, focusing on the selection of resistant/tolerant animals, landscape genomics, metagenomics and gene editing.


L'un des effets anticipés du changement climatique sera la modification de la nature et de la distribution des systèmes d'élevage dans le monde, raison pour laquelle des stratégies seront nécessaires pour adapter et optimiser les systèmes mondiaux de production alimentaire. Si l'on veut que les technologies de la génomique soient utiles dans ce scénario, il faudra procéder avec soin à la définition des phénotypes et à la collecte de routine des échantillons, et réaliser le génotypage à grande échelle des populations animales. Les outils génomiques permettront d'améliorer nettement la caractérisation du germoplasme disponible et d'effectuer une exploration plus approfondie des ressources génétiques locales, tandis que le séquençage ADN devenu plus rapide et meilleur marché se traduira par une meilleure compréhension de la base génétique sousjacente des caractères. Le recours à des outils génomiques pour augmenter la résilience animale, réduire les émissions de méthane du cheptel bovin et ovin, améliorer la résistance aux maladies, diminuer l'impact environnemental, réduire la concurrence pour les terres et les ressources hydrographiques et, enfin, accroître la production pourrait être la voie à suivre la plus réaliste pour l'avenir de la production animale. Les auteurs examinent plusieurs stratégies génomiques à la lumière du changement climatique, en se concentrant sur la sélection des animaux résistants/tolérants, sur la génomique du paysage, sur la métagénomique et sur l'édition génomique.


Según apuntan las predicciones, el cambio climático va a modificar la naturaleza y la distribución de los sistemas agropecuarios del mundo y por doquier en el planeta harán falta estrategias destinadas a adaptar y optimizar los sistemas de producción de alimentos. Para que las herramientas de la genómica sean útiles, en caso de que efectivamente se cumplan estos augurios, es indispensable disponer de detalladas caracterizaciones fenotípicas, muestreos sistemáticos y tipificaciones génicas a gran escala de las poblaciones animales. Las herramientas de la genómica mejorarán mucho la caracterización del germoplasma existente y el estudio de los recursos genéticos locales, a la vez que la secuenciación de ADN, cada vez más rápida y barata, nos aporta ya un conocimiento más profundo de la base genética de los rasgos fenotípicos. Quizá el camino más practicable para el porvenir de la producción ganadera sea el que pasa por utilizar las herramientas de la genómica para conferir más resiliencia a los animales, reducir las emisiones de metano del ganado vacuno y ovino, mejorar la resistencia a enfermedades, atenuar el impacto ambiental, reducir la competencia por los suelos y el agua y, por último, incrementar la producción. Los autores examinan una serie de estrategias genómicas desde la óptica del cambio climático, centrándose en la selección de animales resistentes o tolerantes, la genómica de paisajes, la metagenómica y la edición génica.


Subject(s)
Climate Change , Genomics , Agriculture , Animals , Cattle , Genome , Livestock , Sheep
5.
J Appl Microbiol ; 127(1): 237-247, 2019 Jul.
Article in English | MEDLINE | ID: mdl-30989772

ABSTRACT

AIMS: This study aimed to gather information on farming practices employed in organic lettuce fields in Sao Paulo, Brazil and associate these practices with the microbiological characteristics of the products. METHODS AND RESULTS: Practices were surveyed using a questionnaire applied in ten farms, where 200 heads of lettuce were collected and submitted to enumeration of total coliforms and generic Escherichia coli and tested for Salmonella spp. using culture and molecular (qPCR) methods. Based on the responses, the farms could be clustered in two groups: group 1, comprised by six farms, where chicken manure was used as fertilizer in most of them and the composting process was not performed on site; and group 2, comprised by four farms, where other types of fertilizer were used, and the composting process was performed on site. Generic E. coli was detected in 56 (28%) samples, with an average of 1·1 ± 0·7 log MPN per g. Salmonella DNA was detected in two (1%) samples by qPCR. CONCLUSIONS: The prevalence and bacterial loads of generic E. coli, and the occurrence of Salmonella, even at low populations undetectable by conventional culture methods, highlight the need for control measures during farming practices to reduce microbial contamination and risks of foodborne illnesses. These measures include the use of properly composted manure and appropriate washing procedures for leafy vegetables before consumption. SIGNIFICANCE AND IMPACT OF THE STUDY: The obtained data contribute to a better understanding of the farming practices of organically grown lettuces in Sao Paulo, Brazil.


Subject(s)
Escherichia coli/isolation & purification , Food Microbiology , Lactuca/microbiology , Organic Agriculture/statistics & numerical data , Salmonella/isolation & purification , Brazil , Escherichia coli/genetics , Escherichia coli/growth & development , Farms , Humans , Organic Agriculture/standards , Salmonella/genetics , Salmonella/growth & development
6.
Scand J Immunol ; 86(1): 40-49, 2017 Jul.
Article in English | MEDLINE | ID: mdl-28426172

ABSTRACT

It is well established that helper T cell responses influence resistance or susceptibility to Mycobacterium leprae infection, but the role of more recently described helper T cell subsets in determining severity is less clear. To investigate the involvement of Th17 cells in the pathogenesis of leprosy, we determined the immune profile with variant presentations of leprosy. Firstly, IL-17A, IFN-γ and IL-10 were evaluated in conjunction with CD4+ T cell staining by confocal microscopy of lesion biopsies from tuberculoid (TT) and lepromatous leprosy (LL) patients. Secondly, inflammatory cytokines were measured by multiplex assay of serum samples from Multibacillary (MB, n = 28) and Paucibacillary (PB, n = 23) patients and household contacts (HHC, n = 23). Patients with leprosy were also evaluated for leprosy reaction occurrence: LR+ (n = 8) and LR- (n = 20). Finally, peripheral blood mononuclear cells were analysed by flow cytometry used to determine the phenotype of cytokine-producing cells. Lesions from TT patients were found to have more CD4+ IL-17A+ cells than those from LL patients. Higher concentrations of IL-17A and IL-1ß were observed in serum from PB than MB patients. The highest serum IFN-γ concentrations were, however, detected in sera from MB patients that developed leprosy reactions (MB LR+ ). Together, these results indicate that Th1 cells were associated with both the PB presentation and also with leprosy reactions. In contrast, Th17 cells were associated with an effective inflammatory response that is present in the PB forms but were not predictive of leprosy reactions in MB patients.


Subject(s)
Inflammation Mediators/immunology , Leprosy, Paucibacillary/immunology , Leprosy/immunology , Mycobacterium leprae/immunology , Th1 Cells/immunology , Th17 Cells/immunology , Adolescent , Adult , Aged , Aged, 80 and over , CD4-Positive T-Lymphocytes/immunology , CD4-Positive T-Lymphocytes/metabolism , Child , Contact Tracing , Female , Flow Cytometry , Humans , Inflammation Mediators/blood , Inflammation Mediators/metabolism , Interferon-gamma/blood , Interferon-gamma/immunology , Interferon-gamma/metabolism , Interleukin-10/blood , Interleukin-10/immunology , Interleukin-10/metabolism , Interleukin-17/blood , Interleukin-17/immunology , Interleukin-17/metabolism , Interleukin-1beta/blood , Interleukin-1beta/immunology , Interleukin-1beta/metabolism , Leprosy/blood , Leprosy/microbiology , Leprosy, Multibacillary/blood , Leprosy, Multibacillary/immunology , Leprosy, Multibacillary/microbiology , Leprosy, Paucibacillary/blood , Leprosy, Paucibacillary/microbiology , Male , Microscopy, Confocal , Middle Aged , Mycobacterium leprae/physiology , Th1 Cells/metabolism , Th17 Cells/metabolism , Young Adult
7.
J Phys Condens Matter ; 35(42)2023 Jul 20.
Article in English | MEDLINE | ID: mdl-37429289

ABSTRACT

The growing skill in the synthesis processes of new materials has intensified the interest in exploring the properties of systems modeled by more complex lattices. Two-dimensional super-honeycomb lattices, have been investigated in metallic organic frameworks. They turned out as a significant route to the emergence of localized electronic responses manifested as flat bands in their structure with topological isolating behavior. A natural inquiry is a complete analysis of their topological phases in the presence of electronic correlation effects. Here we analyze the electron-electron correlation effects via Hubbard mean-field approximation on the topological phases of 2D and quasi-1D graphene-Kagome lattices. The 2D spin conductivity phase's diagrams describe metallic, trivial, and topological insulating behaviors, considering different energy coupling and electronic occupations. Our results pave the way to smart-engineered nanostructured devices with relevant applications in spintronics and transport responses.

8.
Mult Scler Relat Disord ; 57: 103331, 2022 Jan.
Article in English | MEDLINE | ID: mdl-35158445

ABSTRACT

BACKGROUND: Cognitive impairment is one of the concerns of Multiple Sclerosis (MS) and has been related to myelin loss. Different neuroimaging methods have been used to quantify myelin and relate it to cognitive dysfunctions, among them Magnetization Transfer Ratio (MTR), Diffusion Tensor Imaging (DTI), and, more recently, Positron Emission Tomography (PET) with 11C-PIB. OBJECTIVE: To investigate different myelin imaging modalities as predictors of cognitive dysfunction. METHODS: Fifty-one MS patients and 24 healthy controls underwent clinical and neuropsychological assessment and MTR, DTI (Axial Diffusion-AD and Fractional Anisotropy-FA maps), and 11C-PIB PET images in a PET/MR hybrid system. RESULTS: MTR and DTI(FA) differed in patients with or without cognitive impairment. There was an association of DTI(FA) and DTI(AD) with cognition and psychomotor speed for progressive MS, and of 11C-PIB uptake and MTR for relapsing-remitting MS. MTR in the Thalamus (ß= -0.51, p = 0.021) and Corpus Callosum (ß= -0.24, p = 0.033) were predictive of cognitive impairment. DTI-FA in the Caudate (ß= -26.93, p = 0.006) presented abnormal predictive result. CONCLUSION: Lower myelin content by 11C-PIB uptake was associated with worse cognitive status. MTR was predictive of cognitive impairment in MS.


Subject(s)
Cognitive Dysfunction , Multiple Sclerosis, Chronic Progressive , Cognitive Dysfunction/diagnostic imaging , Cognitive Dysfunction/etiology , Diffusion Tensor Imaging , Humans , Magnetic Resonance Imaging , Myelin Sheath , Positron-Emission Tomography
9.
Clin Exp Immunol ; 165(3): 338-51, 2011 Sep.
Article in English | MEDLINE | ID: mdl-21726211

ABSTRACT

Leishmaniasis is caused by infection with the protozoan parasite, Leishmania, that parasitizes human cells, and the cellular immune response is essential for controlling infection. In order to measure the host T cell response to Leishmania infection, we have measured the expansion, activation state and functional potential of specific T cells as identified by their T cell receptor Vß region expression. In a group of cutaneous leishmaniasis (CL) patients, we evaluated these characteristics in nine different T cell subpopulations as identified by their Vß region expression, before and after specific Leishmania antigen stimulation. Our results show: (1) an increase in CD4(+) T cells expressing Vß 5·2 and Vß 24 in CL compared to controls; (2) a Leishmania antigen-induced increase in CD4(+) T cells expressing Vß 5·2, 11, 12 and 17; (3) a profile of previous activation of CD4(+) Vß 5·2-, 11- and 24-positive T cells, with higher expression of CD45RO, HLA-DR, interferon-γ, tumour necrosis factor-α and interleukin-10 compared to other Vß-expressing subpopulations; (4) a positive correlation between higher frequencies of CD4(+) Vß5·2(+) T cells and larger lesions; and (5) biased homing of CD4(+) T cells expressing Vß 5·2 to the lesion site. Given that CL disease involves a level of pathology (ulcerated lesions) and is often followed by long-lived protection and cure, the identification of specific subpopulations active in this form of disease could allow for the discovery of immunodominant Leishmania antigens important for triggering efficient host responses against the parasite, or identify cell populations most involved in pathology.


Subject(s)
CD4-Positive T-Lymphocytes/immunology , CD4-Positive T-Lymphocytes/metabolism , Leishmania braziliensis/immunology , Leishmaniasis, Cutaneous/immunology , Leishmaniasis, Cutaneous/pathology , Receptors, Antigen, T-Cell, alpha-beta/metabolism , T-Lymphocyte Subsets/immunology , Adolescent , Adult , Antigens, Protozoan/immunology , CD4 Lymphocyte Count , CD4-Positive T-Lymphocytes/pathology , Cell Movement/immunology , Cytokines/metabolism , Female , HLA-DR Antigens/metabolism , Humans , Interferon-gamma/metabolism , Interleukin-10/metabolism , Leishmania braziliensis/isolation & purification , Leishmaniasis, Cutaneous/diagnosis , Leukocyte Common Antigens/metabolism , Leukocytes, Mononuclear/immunology , Lymphocyte Activation/immunology , Male , Middle Aged , Skin/immunology , Skin/pathology , T-Lymphocyte Subsets/metabolism , T-Lymphocyte Subsets/pathology , Tumor Necrosis Factor-alpha/metabolism , Young Adult
10.
Oral Dis ; 17(5): 484-8, 2011 Jul.
Article in English | MEDLINE | ID: mdl-21504513

ABSTRACT

OBJECTIVE: Microchimerism has been extensively investigated in autoimmune diseases, which display similarities with graft-vs-host disease. This study was conducted to investigate the presence of microchimerism in minor salivary glands of hematopoietic stem cell transplanted patients, one of the targets of graft-vs-host disease. METHODS: Labial salivary glands biopsy specimens from 11 stem cell transplanted patients were analysed. The samples were grouped in control (five specimens from a female-to-female transplantation) and study group (five glands from male-to-female transplantation). One male transplanted patient was used as a positive control. Fluorescence in situ hybridization with Y-chromosome probe and immunofluorescence with anticytokeratin AE1/AE3 and CD45 were used to identify Y-chromosome positive glandular epithelial cells from allogeneic hematopoietic stem cell transplanted patients. RESULTS: In the study group, all samples were positive to Y-chromosome and cytokeratin AE1/AE3, in agreement with the pattern exhibited by male labial salivary gland. None of the samples from control group were positive to Y-chromosome despite being positive to cytokeratin AE1/AE3. Positivity to CD45 was not relevant. CONCLUSION: Microchimerism in the labial salivary glands of sex-mismatched stem cell transplanted patients is a real phenomenon. Further studies are necessary to elucidate the impact of this phenomenon on the clinical status of stem cell transplanted patients.


Subject(s)
Chimerism/classification , Hematopoietic Stem Cell Transplantation/classification , Lip/pathology , Salivary Glands, Minor/pathology , Adolescent , Adult , Biopsy , Chromosomes, Human, Y/genetics , Epithelial Cells/pathology , Female , Fluorescent Antibody Technique , Graft vs Host Disease/pathology , Humans , In Situ Hybridization, Fluorescence , Keratin-1/analysis , Keratin-3/analysis , Leukocyte Common Antigens/analysis , Male , Microscopy, Confocal , Middle Aged , Transplantation, Homologous
11.
Genet Mol Res ; 10(2): 923-31, 2011 May 24.
Article in English | MEDLINE | ID: mdl-21644209

ABSTRACT

The bristle-spined porcupine, Chaetomys subspinosus, an endemic rodent from Atlantic Forest, was considered to be abundant in the recent past, but population reductions due to habitat loss and expansion of human activities caused this species to be included in the "vulnerable" category of the World Conservation Union Red List. We performed the first genetic assessment in natural populations of this focal species along its geographical distribution. Thirty-five non-invasive samples (hair) were collected from three natural populations in the Brazilian States of Sergipe, Bahia and Espírito Santo. Genetic similarity obtained by Jaccard's index, based on dominant RAPD and ISSR markers, varied between 25 and 100%. Four clusters, mainly coincident with the geographical distribution of the populations, were observed. Analysis of molecular variance based on 47 polymorphic loci showed that there was 15.99% genetic variability among populations and 84.01% within populations. The estimated genetic structure among populations (Φ(ST)) was 0.16. The populations may have formed a continuum along the past distribution of the Atlantic rainforest but historical events of human occupation resulted in recent divergence among sampled populations.


Subject(s)
Extinction, Biological , Porcupines/genetics , Animals , Brazil , Conservation of Natural Resources , DNA/genetics , Genetic Markers , Random Amplified Polymorphic DNA Technique
12.
Braz J Med Biol Res ; 54(2): e10462, 2021.
Article in English | MEDLINE | ID: mdl-33439934

ABSTRACT

Infections caused by uncommon and resistant pathogens in unusual sites have been increasingly reported in medical literature. We describe four cases of rare cytological findings and clinical impact for patients. In the first case, Aspergillus sp and Pneumocystis jirovecii were observed in the bronchoalveolar lavage of a patient with severe systemic lupus. In the second and third cases, we describe the presence of Trichomonas sp and Strongyloides sp larvae in samples of pleural and peritoneal fluid, respectively. The fourth report is about a patient with a wrist subcutaneous nodule whose synovial aspiration and cytology revealed the presence of brown septate hyphae. The early identification of the infectious agent in the cytological examination was essential for the introduction and/or re-adaptation of therapy in the four cases described. Patients in this report were immunocompromised with severe comorbidities, conditions often associated with unfavorable clinical outcomes.


Subject(s)
Communicable Diseases/diagnosis , Cytodiagnosis/methods , Animals , Ascitic Fluid/parasitology , Aspergillus/isolation & purification , Bronchoalveolar Lavage Fluid/microbiology , Fatal Outcome , Female , Humans , Male , Middle Aged , Pleural Effusion/parasitology , Pneumocystis carinii/isolation & purification , Strongyloides/isolation & purification , Strongyloidiasis/diagnosis , Trichomonas/isolation & purification , Trichomonas Infections/diagnosis
13.
J Mech Behav Biomed Mater ; 112: 104049, 2020 12.
Article in English | MEDLINE | ID: mdl-32942227

ABSTRACT

OBJECTIVES: The aim of this study was to develop a novel design for implants surface functionalization through the production of HAp-coated zirconia structured surfaces by means of hybrid laser technique. The HAp-rich structured surfaces were designed to avoid hydroxyapatite (HAp) coating detachment from the zirconia surface during implant insertion, thus guaranteeing an effective osseointegration. MATERIALS AND METHODS: The functionalization process of zirconia surface started by creating micro-textures using a Nd:YAG laser and subsequent deposition of a HAp coating on the designated locations by dip-coating process. Afterwards, a CO2 laser was used to sinter the HAp coating. The potential of the HAp-coated zirconia structured surfaces was inspected concerning HAp bioactivity preservation, surface wettability, HAp coating adhesion to the textured surfaces and mechanical resistance of zirconia, as assessed by different approaches. RESULTS: The functionalized surfaces exhibited a superhydrophilic behavior (2.30 ± 0.81°) and the remaining results showed that through the hybrid strategy, it is possible to maintain the HAp bioactivity as well as promote a strong adhesion of HAp coating to the textured surfaces even after high energy ultrasonic cavitation tests and friction tests against bovine bone. It was also verified that the flexural strength of zirconia (503 ± 24 MPa) fulfills the strict requirements of the ISO 13356:2008 standard and as such is expectable to be enough for biomedical applications. SIGNIFICANCE: The promising results of this study indicate that the proposed surface design can open the window for manufacturing zirconia-based implants with improved bioactivity required for an effective osseointegration as it avoids the coating detachment problem during the implant insertion.


Subject(s)
Durapatite , Zirconium , Animals , Cattle , Coated Materials, Biocompatible , Lasers , Surface Properties , Titanium
14.
Mater Sci Eng C Mater Biol Appl ; 108: 110390, 2020 Mar.
Article in English | MEDLINE | ID: mdl-31923937

ABSTRACT

The development of new surface designs to enhance the integration process between surgically placed implants and biological tissues remains a challenge for the scientific community. In this way and trying to overcome this issue, in this work, laser technology was explored to produce novel textures on the surface of green zirconia compacts produced by cold pressing technique. Two strategies regarding line design (8 and 16 lines design) and different laser parameters (laser power and number of laser passages) were explored to assess their influence on geometry and depth of created textures. The produced textures were evaluated with Scanning Electron Microscopy (SEM) and it was observed that well-defined textured surfaces with regular geometric features (cavities or pillars) were obtained by laser combining different strategies lines design and parameters. The potential of proposed textures was also evaluated regarding surface wettability, friction performance (static and dynamic coefficient of friction evolution) against bone, aging resistance and flexural strength. Results demonstrated that all the produced textures display a super hydrophilic or hydrophilic behavior. Regarding the friction behavior, it was experimentally observed a high initial static coefficient of friction (COF) for all produced textures. Concerning the aging resistance, all the textured surfaces revealed a low monoclinic content, less than 25% after 5 h of hydrothermal aging. The flexural strength results showed that the mechanical resistance of zirconia was not significantly compromised with the laser action. Based on the obtained results, it is possible to prove that the processing route used for manufacturing the new and different surface designs (cold pressing technique followed by laser texturing) showed to be particularly effective for the production of zirconia implants with customized surface designs according to the properties required in a specific application. These new surface designs besides to enhance the surface wettability and also to improve the fixation at the initial moment of the implantation, do not significantly compromise the resistance to aging and the mechanical performance of zirconia. Hence, a positive impact on the long-term performance of the zirconia implants may be expected with the proposed novel laser textured surface designs.


Subject(s)
Lasers , Prostheses and Implants , Zirconium/chemistry , Materials Testing , Microscopy, Electron, Scanning , Surface Properties , Temperature
15.
Parasite Immunol ; 31(8): 432-9, 2009 Aug.
Article in English | MEDLINE | ID: mdl-19646207

ABSTRACT

Human infection with Leishmania braziliensis leads to the establishment of cutaneous leishmaniasis (CL), characterized by the appearance of skin lesions that progress from nonulcerated to ulcerated forms. Our goal was to characterize the immunological kinetics associated with this progression, comparing the cellular composition, cytokines and granzyme expression between lesions of patients with early (E-CL) and late stages (L-CL) of CL. Histopathological analysis showed that lesions from L-CL had more exuberant inflammatory infiltrate as compared to E-CL. Although E-CL and L-CL lesions were predominantly mononuclear, lesions from E-CL patients presented higher neutrophil and eosinophil counts than L-CL. While percentages of CD4(+) and of CD68(+) cells were slightly higher in L-CL, a fivefold increase of CD8(+) cells was observed in L-CL, as compared to E-CL. Moreover, CD8(+) T-cells from L-CL expressed significantly higher levels of granzyme A than E-CL. Interestingly, granzyme A expression was positively correlated with intensity of the inflammatory infiltrate in L-CL but not E-CL. Lastly, percentages of IFN-gamma(+) and IL-10(+) cells were higher in L-CL as compared to E-CL, with CD4(+) T-cells and CD68(+) monocytes as the main sources of these cytokines, respectively. These results suggest that recruitment of CD8(+) granzyme A(+) T cells is involved in lesion progression in human CL.


Subject(s)
CD8-Positive T-Lymphocytes/immunology , Granzymes/metabolism , Leishmania braziliensis , Leishmaniasis, Cutaneous/immunology , Leishmaniasis, Cutaneous/pathology , Animals , CD4-Positive T-Lymphocytes/cytology , CD8-Positive T-Lymphocytes/enzymology , Cell Count , Disease Progression , Eosinophils/cytology , Humans , Inflammation/immunology , Interferon-gamma/biosynthesis , Interleukin-10/biosynthesis , Leukocytes, Mononuclear/cytology , Neutrophils/cytology , Skin/parasitology , Skin/pathology
16.
Sci Rep ; 9(1): 3173, 2019 02 28.
Article in English | MEDLINE | ID: mdl-30816173

ABSTRACT

Human migration and trade facilitated domesticated livestock movement, gene flow and development of diverse populations upon which agriculture is based. In addition, varying USA ecological conditions has led to a diverse set of livestock populations to utilize. Quantifying genetic diversity of these populations is incomplete. This paper quantifies genetic diversity captured by the National Animal Germplasm Program and explores genetic structure and differences among 19 pig populations (feral populations from Pacific islands, continental US, and Chinese breeds) using 70,231 SNP from 500 animal samples. Among continental US breeds Fis was consistently low suggesting genetic variability is sufficiently available for breeders to use. A unique population structure using principal component analysis illustrated clear distinctions between Duroc, Yorkshire, Hampshire, breeds of Chinese origin, and feral Pacific Island populations were identified. Five Y chromosome haplotypes were evaluated and demonstrated migration patterns from European, central Asia, and potentially Polynesian waves of gene flow. Quantifying diversity and potential origin of Pacific populations provides insight for future uses, and the need for preservation. Viewing gene bank holdings in context of diversity measures we found a lack of inbreeding within breeds, suggesting the collection represents a wide sampling of individual breeds.


Subject(s)
Animals, Domestic/genetics , Genetic Variation/genetics , Genetics, Population , Sus scrofa/genetics , Animals , Breeding , China , Gene Flow/genetics , Genotype , Haplotypes/genetics , Human Migration , Humans , Inbreeding , Pacific Islands , Polymorphism, Single Nucleotide/genetics , Swine , United States , Y Chromosome/genetics
17.
Sci Total Environ ; 646: 280-289, 2019 Jan 01.
Article in English | MEDLINE | ID: mdl-30055490

ABSTRACT

In the domestic segment, various appliances and processes consume great amount of water and, consequently, energy. In this context, the main aim of this study is to analyse the impact of water temperature, flow and bath duration in water and energy consumptions. The impact on CO2 emissions and a simple costs analysis were also carried out. It included a monitoring plan of 197 baths taken under different scenarios of water temperature and flow. It was concluded that increasing water consumption leads to an increase on energy consumption and that both resources consumptions increase with bath duration. Bath temperature had influence not only on energy consumption, as expected, but also in water consumption, what may be explained by the user's satisfaction during baths with higher temperatures. The use of a flow reducing valve is not a guarantee of water saving which can also be related to the user's satisfaction patterns, given that the introduction of a flow reducing valve can lead to a bath duration increase. In what concerns to the CO2 emissions, it was concluded, as expected, that higher values are obtained for baths with higher temperatures given their relation with higher energy consumptions patterns. A simple costs analysis revealed that having flow reducing valves, with a bath temperature of 75 °C, increased the costs with electricity and water in 119% and 32%, respectively, when compared with a temperature of 60 °C.


Subject(s)
Baths/economics , Carbon Dioxide/analysis , Conservation of Water Resources/methods , Baths/statistics & numerical data , Conservation of Water Resources/economics , Conservation of Water Resources/statistics & numerical data , Hot Temperature , Temperature , Water Supply/economics , Water Supply/methods , Water Supply/statistics & numerical data
18.
J Mech Behav Biomed Mater ; 94: 110-125, 2019 06.
Article in English | MEDLINE | ID: mdl-30884280

ABSTRACT

Zirconia implants are becoming a preference choice for different applications such as knee, dental, among others. In order to improve osseointegration, implant's surfaces are usually coated with bioactive materials like hydroxyapatite (HAp) and beta-tricalcium phosphate (ß-TCP) that are very similar to the calcium phosphates found in bones. However, due to the implantation process, these coatings can be detached from the zirconia surface, leading to implant premature failure. In this work, a new component materials design aiming to avoid this coating detachment problem is proposed. It is based on the use of a bioactive zirconia-calcium phosphate composite outer layer onto the zirconia bulk, where the zirconia bulk provides mechanical strength and the outer layer provides biological performance. In order to assess the potential of this new materials design, two types of bioactive zirconia outer composite layers (zirconia reinforced by 10 vol% of HAp and by 10 vol% of ß-TCP) were produced by press and sinter process and the gradated samples were fully characterized concerning materials, mechanical resistance, fatigue resistance, and biological performance, as measured by different approaches. Results showed that the novel component materials design and the manufacturing process proposed for producing the bioactive zirconia samples with outer composite layers on zirconia bulk substrates are a promising solution for implants, with improved biological performance without substantially compromising their overall mechanical and fatigue properties.


Subject(s)
Prostheses and Implants , Zirconium/chemistry , Calcium Phosphates/chemistry , Durapatite/chemistry , Elastic Modulus , Hardness , Surface Properties , Temperature , Wettability
19.
J Biomed Mater Res B Appl Biomater ; 106(4): 1534-1545, 2018 05.
Article in English | MEDLINE | ID: mdl-28748671

ABSTRACT

This work presents a novel texture design for implants surface functionalization, through the creation of line-shaped textures on Ti6Al4V surfaces and subsequent sintering of hydroxyapatite (HAp) powder into the designated locations. HAp-rich locations were designed to avoid HAp detachment during insertion, thus guaranteeing an effective osseointegration. This process starts by creating textured lines using a Nd:YAG laser, filling these lines with HAp powder and sintering HAp using a CO2 laser. The adhesion of HAp is known to be influenced by HAp sintering parameters, especially laser power and scanning speed and also by the textured lines manufacturing. Different laser parameters combinations were used to assess the sintering and adhesion of HAp to the textured lines. HAp adhesion was assessed by performing high energy ultrasonic cavitation tests and sliding tests mimicking an implant insertion, with Ti6Al4V/HAp specimens sliding against animal bone. The HAp content retained after these tests was measured and results showed that an excellent HAp sintering and adhesion was achieved when using a scan speed of 1 mm/s and laser power between 9 and 9.6 W. It is important to emphasize that results indicated that the HAp bioactivity was maintained when using these conditions, validating this functionalization process for the production of hip prosthesis with improved bioactivity. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 1534-1545, 2018.


Subject(s)
Coated Materials, Biocompatible/chemistry , Durapatite/chemistry , Titanium/chemistry , Alloys , Lasers , Osseointegration , Surface Properties
20.
Sci Total Environ ; 642: 421-435, 2018 Nov 15.
Article in English | MEDLINE | ID: mdl-29906732

ABSTRACT

Rural and urban environments present significant differences between water and energy consumptions. It is important to know, in detail, which factors related to the consumption of these two resources are different in both environments, once that will be those important to manage and discuss in order to improve its use efficiency and sustainability. This research work involves a survey whose aim is to find the factors that in rural and urban environments may justify the differences found in water and energy consumptions. Besides the collection of water and energy consumption data, this survey analyzed 80 variables (socio-demographic, economic, household characterization, among others), that were chosen among the bibliography as possible factors that should influence water and energy consumptions. After the survey application in rural and urban areas and the data statistical treatment, 42 variables remained as truly differentiating factors of rural and urban environments and so as possible determinants of water and energy consumptions. In order to achieve these objectives, a descriptive data analysis and statistical inference (Mann-Whitney-Wilcoxon test and the Chi-square test of homogeneity) were performed. All the 42 differentiating variables that result from this study may be able to justify these differences, however this will not be presented in the paper and it is reserved for future work.

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