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2.
Eur Arch Paediatr Dent ; 24(1): 63-73, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36239737

ABSTRACT

PURPOSE: Estimate the incidence of teething symptoms and investigate risk factors at three centers in different regions of Brazil. METHODS: A prospective cohort study enrolled children at birth in the cities of Manaus (northern region), Porto Alegre (southern region) and Salvador (northeast region). Sociodemographic and anthropometric variables were collected at baseline and 6 months. At 12 months, data were collected on the child's health through structured interviews and dental examinations, including the primary outcome: occurrence of signs and symptoms of tooth eruption reported by parents. Statistical analysis involved Poisson regression with robust variance, with calculation of relative risks (RR). RESULTS: The incidence of teething symptoms was 82.4% (238/289). The multivariate analysis revealed a higher occurrence of the outcome in the city of Salvador (RR = 1.39; 95% CI 1.23-1.58), when mother's education was more than 11 years (RR = 1.31; 95% CI 1.04-1.65), when a larger number of individuals resided in the home (RR = 1.15; 95% CI 1.02-1.29), when a smoker resided in the home (RR = 1.16; 95% CI 1.03-1.31) and when the child presented flu or cold in the first year of life (RR = 1.23; 95% CI 1.09-1.38). The most reported symptoms were fever (50.5%), irritability (42.6%), itching (40.8%) and diarrhea (35.3%). Most parents (82%) took some action to alleviate symptoms, including unprescribed systemic medication, such as analgesic, anti-inflammatory and anti-diarrheic agents. CONCLUSION: Reports of teething symptoms were associated with the city investigated, socioeconomic factors of the families and characteristics of the child's health. A high rate of administering unprescribed medication was also found.


Subject(s)
Tooth Eruption , Infant, Newborn , Child , Humans , Cohort Studies , Brazil/epidemiology , Prospective Studies , Risk Factors
3.
Braz J Biol ; 82: e262364, 2022.
Article in English | MEDLINE | ID: mdl-35857950

ABSTRACT

Basil (Ocimum basilicum) is a medicinal, ornamental and aromatic plant, however, its size can be an obstacle to its commercialization as a potted ornamental plant. Paclobutrazol (PBZ) is a substance that can retard plant growth by inhibiting the synthesis of gibberellins. The objective of this work was to evaluate the effect of paclobutrazol on growth regulation and gas exchange of basil (var. Cinnamon). The experiment was carried out in a completely randomized design with five treatments (PBZ doses: 0, 2.5, 5, 7.5 and 10 mg L-1), with eight replicates. Growth (plant height, number of leaves, stem diameter, leaf dry mass, stem dry mass, inflorescence dry mass, and total), growth rates (leaf mass ratio, stem mass ratio, inflorescence mass ratio, and robustness quotient), chlorophyll indices, gas exchange (gs, A, E, Ci, WUE, iWUE and iCE) were evaluated. Paclobutrazol reduced the growth of basil plants and increased the chlorophyll indices, A, gs, and WUE. Paclobutrazol can be used to regulate plant growth of basil plants var. Cinnamon, without altering its physiological and ornamental characteristics.


Subject(s)
Ocimum basilicum , Chlorophyll , Plant Leaves , Triazoles
4.
Int J Pharm ; 622: 121829, 2022 Jun 25.
Article in English | MEDLINE | ID: mdl-35580686

ABSTRACT

The oral route is the best way to administer a drug; however, fitting peptide drugs in this route is a major challenge. In insulin cases, less than 0.5% of the administered dose achieves systemic circulation. Oral delivery by nanoparticles can increase insulin permeability across the intestinal epithelium while maintaining its structure and activity until release in the gut. This system can be improved to increase permeability across intestinal cells through active delivery. This study aimed to improve a nanoparticle formulation by promoting functionalization of its surface with immunoglobulin G to increase its absorption by intestinal epithelium. The characterization of formulations showed an adequate size and a good entrapment efficiency. Functionalized nanoparticles led to a desirable increase in insulin release time. Differential scanning calorimetry, infrared spectroscopy and paper chromatography proved the interactions of nanoparticle components. With immunoglobulin G, the nanoparticle size was slightly increased, which did not show aggregate formation. The developed functionalized nanoparticle formulation proved to be adequate to carry insulin and potentially increase its internalization by epithelial gut cells, being a promising alternative to the existing formulations for orally administered low-absorption peptides.


Subject(s)
Insulin , Nanoparticles , Administration, Oral , Drug Carriers/chemistry , Immunoglobulin G , Nanoparticles/chemistry , Pharmaceutical Preparations , Polymers/chemistry
5.
Braz J Biol ; 84: e260522, 2022.
Article in English | MEDLINE | ID: mdl-35475995

ABSTRACT

Fall armyworm (Spodoptera frugiperda) is the main species that causes damage to the maize crop in Brazil. In the perspective of studying alternatives of control of this pest that preserve the natural enemies, the aim of this research was to evaluate the insecticidal efficiency of the essential oils of Vanillosmopsis arborea and Lippia microphylla on S. frugiperda and verify the selectivity to the predator Euborellia annulipes. The bioassays were carried out in the Agricultural Entomology Laboratory of the Federal University of Paraiba, using insects, from 3rd instar of S. frugiperda and E. annulipes, originating from mass rearing in the laboratory itself. Dilutions of the oils were performed in Tween® 80 at concentrations of 0, 100, 150 and 200 mg mL-1. 1.0 µL from each dilution was applied to the prothoracic region of the insects. The S. frugiperda mortality was verified by topical contact of V. arborea oil with LC10 = 74.3 mg mL-1 and LC50 = 172.86 mg mL-1, for L. microphyla, LC10 = 51.26 mg mL-1 and LC50 = 104.52 mg mL-1. The observed lethal concentrations for E. annulipes were V. arborea LC10 = 71.3 mg mL-1 and LC50 = 160.2 mg mL-1. While L. microphyla, were LC10 = 50.3 mg mL-1 and LC50 = 134.67 mg mL-1. The essential oils of V. arborea and L. microphylla are efficient in the control of S. frugiperda, but are not selective to the predator E. Annulipes.


Subject(s)
Insecticides , Lippia , Oils, Volatile , Animals , Brazil , Insecticides/toxicity , Oils, Volatile/pharmacology , Spodoptera
6.
ScientificWorldJournal ; 2021: 9512854, 2021.
Article in English | MEDLINE | ID: mdl-34434079

ABSTRACT

This narrative review addresses resilience and stress during pregnancy, which is part of a broader concept of maternal health. Pregnancy and postpartum are opportune periods for health promotion interventions, especially because the close contact of the women with health professionals. In this way, it can be considered a useful window of opportunity to identify women at higher risk for adverse outcomes. Integrated health is a concept that aims at providing comprehensive care related to the promotion of individuals' physical, mental, and social well-being. In this context, stress during pregnancy has been targeted as a remarkable condition to be addressed whether due to individual issues, social issues, or specific pregnancy issues, since it is directly and indirectly associated with pregnancy complications. Stress is associated with preterm birth, postpartum depression, anxiety, child neurodevelopment, and fetal distress. The way that an individual faces a stressful and adverse situation is called resilience; this reaction is individual, dynamic, and contextual, and it can affect maternal and fetal outcomes. Low resilience has been associated with poorer pregnancy outcomes. The social context of pregnancy can act as a protective or contributory (risk) factor, indicating that environments of high social vulnerability play a negative role in resilience and, consequently, in perceived stress. A given stressor can be enhanced or mitigated depending on the social context that was imposed, as well as it can be interpreted as different degrees of perceived stress and faced with a higher or lower degree of resilience. Understanding these complex mechanisms may be valuable for tackling this matter. Therefore, in the pregnancy-puerperal period, the analysis of the stress-resilience relationship is essential, especially in contexts of greater social vulnerability, and is a health-promoting factor for both the mother and baby.


Subject(s)
Anxiety/prevention & control , Depression, Postpartum/prevention & control , Maternal Health , Pregnancy Complications/prevention & control , Resilience, Psychological , Stress, Psychological/prevention & control , Female , Fetal Distress/prevention & control , Fetus , Humans , Infant, Newborn , Parturition/psychology , Perinatal Care/organization & administration , Pregnancy , Premature Birth/prevention & control , Premature Birth/psychology , Social Vulnerability
7.
Mater Sci Eng C Mater Biol Appl ; 120: 111735, 2021 Jan.
Article in English | MEDLINE | ID: mdl-33545878

ABSTRACT

One of the main problems that remain in the implant industry is poor osseointegration due to bioinertness of implants. In order to promote bioactivity, calcium (Ca), phosphorus (P) and strontium (Sr) were incorporated into a TiO2 porous layer produced by micro-arc oxidation. Ca and P as bioactive elements are already well reported in the literature, however, the knowledge of the effect of Sr is still limited. In the present work, the effect of various amounts of Sr was evaluated and the morphology, chemical composition and crystal structure of the oxide layer were investigated. Furthermore, in vitro studies were carried out using human osteoblast-like cells. The oxide layer formed showed a triplex structure, where higher incorporation of Sr increased Ca/P ratio, amount of rutile and promoted the formation of SrTiO3 compound. Biological tests revealed that lower concentrations of Sr did not compromise initial cell adhesion neither viability and interestingly improved mineralization. However, higher concentration of Sr (and consequent higher amount of rutile) showed to induce collagen secretion but with compromised mineralization, possibly due to a delayed mineralization process or induced precipitation of deficient hydroxyapatite. Ca-P-TiO2 porous layer with less concentration of Sr seems to be an ideal candidate for bone implants.


Subject(s)
Coated Materials, Biocompatible , Strontium , Humans , Osseointegration , Surface Properties , Titanium
8.
Arq. bras. med. vet. zootec. (Online) ; 72(2): 461-470, Mar./Apr. 2020. tab
Article in Portuguese | LILACS, VETINDEX | ID: biblio-1128377

ABSTRACT

Devido à ausência de estudos sobre capivaras na região Nordeste do Brasil, o objetivo deste estudo foi avaliar a sanidade desses roedores de vida livre em três áreas dos biomas Mata Atlântica (2) e Caatinga (1) do estado de Pernambuco, por meio da determinação de parâmetros da hematologia e bioquímica sérica. De novembro de 2016 a dezembro de 2017, foram capturados 21 animais, dos quais foram coletadas amostras de sangue para avaliação hematológica (eritrograma, leucograma e plaquetometria) e bioquímica sérica (atividade enzimática, perfil proteico, energético e mineral). A maioria dos parâmetros esteve dentro dos valores de normalidade para a espécie, embora alguns apresentassem diferenças estatisticamente significativas de acordo com a área de estudo (hemoglobina, hematócrito, VCM, CHCM, eosinófilos, fosfatase alcalina, proteína total, albumina, ácido úrico, creatinina, lactato, sódio e magnésio) e o sexo dos animais (ácido úrico). Os parâmetros obtidos são apresentados como referência e atestam a sanidade e o bom estado nutricional de populações de capivaras nos biomas Mata Atlântica e Caatinga da região Nordeste do Brasil. As informações aportadas neste estudo pioneiro na região Nordeste contribuem para aumentar o conhecimento sobre a ecofisiologia e a conservação in situ de capivaras.(AU)


Due to the lack of studies about capybaras in the northeast region of Brazil, the objective of this study was to evaluate the health status of free-ranging capybaras in three areas of Atlantic Forest (2) and Caatinga (1) biomes in Pernambuco state, through the determination of hematological and serum biochemical parameters. From November 2016 to December 2017, 21 animals were captured and blood samples were collected for the hematological (erythrogram, leukogram and platelet counts) and serum biochemistry (enzymatic activity, protein, energy and mineral profile) evaluation. Hematological and serum biochemical parameters were within the normal range for the species, but some presented statistically significant variations according to the study area (hemoglobin, hematocrit, MCV, MCHC, eosinophils count, alkaline phosphatase, total proteins, albumin, uric acid, creatinine, lactate, sodium and magnesium) and sex of the animals (uric acid). The parameters obtained are presented as reference and attest to the health and good nutritional status of populations of capybaras in the Atlantic Forest and Caatinga biomes of northeastern Brazil. The information provided in this pioneering study in the northeast region contributes to increased knowledge about the ecophysiology and in situ conservation of capybaras.(AU)


Subject(s)
Animals , Rodentia/blood , Biochemical Phenomena , Ecosystem , /methods , Hematologic Tests/veterinary
9.
Rev. Soc. Cardiol. Estado de Säo Paulo ; 29(Suppl. 2b): 157-157, Jun. 2019.
Article in Portuguese | Sec. Est. Saúde SP, SESSP-IDPCPROD, Sec. Est. Saúde SP | ID: biblio-1009790

ABSTRACT

INTRODUÇÃO: A cardiomiopatia hipertrófica (CMHP) é uma doença cardíaca genética comum, com frequência aproximada de 1:500 na população geral e com expressões fenotípicas diversas. A forma obstrutiva caracteriza-se pela presença de gradiente pressórico intraventricular dinâmico, com manifestações mais graves e de difícil controle, sendo a realização de esforço físico contra indicada até recentemente, considerando-se a susceptilidade a arritmias ventriculares graves. Das variáveis do teste ergométrico a pressão arterial sistólica (PAS) é considerada fator determinante para morte súbita. OBJETIVO: avaliar a segurança do TCPE em pacientes com CMPH obstrutiva, bem como avaliar adicionalmente o comportamento de suas variáveis no auxílio à estratificação do risco cardiovascular. MÉTODOS: Foram incluídos pacientes com CMPH obstrutiva que realizaram TCPE entre o ano de 2013 e 2018. RESULTADOS: avaliados 18 pacientes com média de idade de 51 anos (DP 17.1) e 12 (67%) mulheres. Para caracterização anatômica foi empregada a ecodopplercardiografia que evidenciou: gradiente máximo da via de saída do ventrículo esquerdo: de 80 mmHg (DP 32.5); espessura septal (diástole) de 20 mm (DP 6.72); fração de ejeção do ventrículo esquerdo (FEVE) de 69.5 (DP 10.9). Todos em vigência de medicação específica, ressaltando-se os betabloqueadores em 16 pacientes (89%). Das variáveis obtidas durante o esforço, destacam-se as médias de tempo de exercício: 9,1 (DP 2.9) minutos ; frequência cardíaca pico = 111 (DP 19,4) bpm ou 65% do máxima; variação da PAS = 24.5 mmHg (DP 19.4), com curva deprimida em 75% dos pacientes; consumo de oxigênio pico de 18,25 ml.kg-1.min-1(DP 6.4), correspondendo a 62% do valor predito; VE / VCO2 slope = 30,2 (DP 7,60), Razão de trocas respiratórias ou RER = 1,02 (DP 0.13). Não houve arritmias ventriculares sustentadas, parada cardiorrespiratória, ou outra complicação que necessitasse de internação. CONCLUSÃO: Na amostra de pacientes avaliados o TCPE mostrou-se seguro durante sua realização em ambiente hospitalar, com variáveis hemodinâmicas e ventilatórias que podem auxiliar na caracterização prognóstica e no processo de decisão médica. (AU)


Subject(s)
Humans , Cardiomyopathy, Hypertrophic , Cardiovascular Diseases , Risk
10.
J Biomed Mater Res B Appl Biomater ; 107(1): 73-85, 2019 01.
Article in English | MEDLINE | ID: mdl-29520948

ABSTRACT

Highly porous Ti implant materials are being used in order to overcome the stress shielding effect on orthopedic implants. However, the lack of bioactivity on Ti surfaces is still a major concern regarding the osseointegration process. It is known that the rapid recruitment of osteoblasts in bone defects is an essential prerequisite for efficient bone repair. Conventionally, osteoblast recruitment to bone defects and subsequent bone repair has been achieved using growth factors. Thus, in this study highly porous Ti samples were processed by powder metallurgy using space holder technique followed by the bio-functionalization through microarc oxidation using a Ca- and P-rich electrolyte. The biological response in terms of early cell response, namely, adhesion, spreading, viability, and proliferation of the novel biofunctionalized highly porous Ti was carried out with NIH/3T3 fibroblasts and MC3T3-E1 preosteoblasts in terms of viability, adhesion, proliferation, and alkaline phosphatase activity. Results showed that bio-functionalization did not affect the cell viability. However, bio-functionalized highly porous Ti (22% porosity) enhanced the cell proliferation and activity. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 107B: 73-85, 2019.


Subject(s)
Cell Adhesion , Cell Differentiation , Cell Proliferation , Implants, Experimental , Osteoblasts/metabolism , Osteogenesis , Titanium/chemistry , Animals , Mice , NIH 3T3 Cells , Osteoblasts/cytology , Porosity
11.
Transplant Proc ; 50(3): 804-808, 2018 Apr.
Article in English | MEDLINE | ID: mdl-29661442

ABSTRACT

OBJECTIVE: Acute rejection is one of the most common complications after pulmonary transplantation. The aim of this work was to verify the association of nutritional status and weight gain with acute rejection in the recipient during the 1st year after pulmonary transplantation. METHODS: Retrospective cohort study with patients submitted to pulmonary transplantation at a pulmonary transplantation center in the state of São Paulo. Data on sex, age, underlying disease, type of transplantation, and presence, degree, and frequency of rejection according to the transbronchial biopsy results were collected, along with body mass index (BMI) and weight variation over the course of 1 year. The difference between groups was analyzed by means of Student t test and the association by means of chi-square test. Significance was considered with P < .05. RESULTS: A total of 117 patients were included, of which 71 (60.7%) were male. The average age was 39.8 ± 15.5 years. There were 77.8% with acute rejection in the 1st year after transplantation. The nutritional status of eutrophy prevailed according to BMI in both adolescents and adults, with no association with acute rejection (P = .80), and there was a greater weight gain among the individuals who showed rejection, with an increase of 7.58 kg (95% confidence interval [CI] 6.35-8.81) compared with those who did not present rejection, whose average weight gain was 4.12 kg (95% CI 1.28-6.95; P = .01). CONCLUSIONS: Nutritional status was not associated with acute cell rejection in the 1st year after transplantation, although weight gain was greater in those who had rejection.


Subject(s)
Graft Rejection/etiology , Lung Transplantation/adverse effects , Weight Gain , Adult , Biopsy , Body Mass Index , Female , Humans , Lung/pathology , Male , Postoperative Period , Retrospective Studies
12.
J Mech Behav Biomed Mater ; 74: 195-203, 2017 10.
Article in English | MEDLINE | ID: mdl-28609705

ABSTRACT

Ti and its alloys are attractive materials for variety of fields, including biomedical implants, however, the wear behavior is yet to be improved. In the present work, Ti-TiB-TiNx in-situ metal matrix composites were synthesized by reactive hot pressing using a Ti-BN powder blend. Corrosion behavior was investigated in 9g/L NaCl solution at 37°C by performing potentiodynamic polarization and electrochemical impedance spectroscopy. Tribocorrosion behavior was investigated using reciprocating tribometer, against an alumina ball, under 1 and 10N normal load, 1 and 2Hz frequency, in 9g/L NaCl solution at 37°C. Results suggested that TiB and TiNx in-situ phases did not deteriorate the corrosion behavior of Ti but significantly improved the tribocorrosion behavior under 1N.


Subject(s)
Materials Testing , Prostheses and Implants , Titanium/chemistry , Alloys , Corrosion
13.
Lett Appl Microbiol ; 65(2): 125-132, 2017 Aug.
Article in English | MEDLINE | ID: mdl-28561264

ABSTRACT

Trueperella pyogenes is an opportunistic pathogen that causes diverse pyogenic infections in livestock. The genes that encode the exotoxin pyolysin (plo) and other putative factors that promote adhesion of pathogen to host cells (fimbriae fimA, fimC, fimE, fimG, neuraminidases nanH, nanP, and collagen-binding protein cbpA) have been associated with virulence, particularly in mastitis and uterus infections of dairy cows. However, the role of these virulence markers in the pathogenicity of the agent in domestic animals infections still is incompletely understood. The genes plo, fimA, fimC, fimE, fimG, nanH, nanP, and cbpA were investigated in 71 T. pyogenes strains recovered from cattle, sheep, goats, dogs, equines, and a pig, recovered from mastitis (n = 35), and non-mastitis (n = 36) cases (abscesses, reproductive tract diseases, pneumonia, lymphadenitis, encephalitis). The most common genes harboured by the isolates were: plo (71/71 = 100·0%), fimA (70/71 = 98·6%), nanP (56/71 = 78·9%), fimE (53/71 = 74·6%), fimC (46/71 = 64·8%) and nanH (45/71 = 63·4%), whereas cbpA (6/71 = 8·4%) and fimG (4/71 = 5·6%) were uncommon. The most frequent genotypes were plo/fimA/fimE/fimC/nanH/nanP (17/71 = 23·9%), plo/fimA/fimE/nanH/nanP (13/71 = 18·3%), and plo/fimA/fimE/fimC/nanP (11/71 = 15·5%). No association was observed between the presence of genes vs clinical signs or host species. To the best of our knowledge, this is the first report on aforementioned virulence factors of pathogen detected in diseased horses and dogs. SIGNIFICANCE AND IMPACT OF THE STUDY: The role of particular virulence factors of Trueperella pyogenes that determine different pyogenic infections among domestic animals is poorly understood. Eight putative virulence genes and genotype profiles of 71 isolates were investigated among different clinical manifestations in domestic animals. The most common genes were plo (71/71 = 100·0%), fimA (70/71 = 98·6%), nanP (56/71 = 78·9%), fimE (53/71 = 74·6%), fimC (46/71 = 64·8%) and nanH (45/71 = 63·4%), whereas plo/fimA/fimE/fimC/nanH/nanP (17/71 = 23·9%), plo/fimA/fimE/nanH/nanP (13/71 = 18·3%), and plo/fimA/fimE/fimC/nanP (11/71 = 15·5%) were the most frequent genotypes. Studies involving virulence factors are critical in the investigation of molecular epidemiology, pathogenicity, and hypothetical differences in the virulence among T. pyogenes strains from different geographical areas.


Subject(s)
Actinomycetales Infections/veterinary , Arcanobacterium/pathogenicity , Mastitis/veterinary , Virulence Factors/genetics , Actinomycetales Infections/microbiology , Animals , Arcanobacterium/genetics , Bacterial Proteins/genetics , Bacterial Toxins/genetics , Cattle , Dogs , Female , Genotype , Goats , Hemolysin Proteins/genetics , Horses , Livestock , Mastitis/microbiology , Pets , Sheep , Swine , Virulence
14.
Lett Appl Microbiol ; 64(6): 419-423, 2017 Jun.
Article in English | MEDLINE | ID: mdl-28349671

ABSTRACT

Prototheca species have increasingly been reported to be opportunistic pathogens that cause mastitis in dairy herds, and it poses an emergent problem because at present, there are no effective therapies for the treatment of protothecal mastitis. This study investigated the in vitro algicidal effect of guanidine on 75 Prototheca zopfii genotype 2 strains isolated from 75 cases of clinical and subclinical bovine mastitis. All strains were susceptible to guanidine in vitro with minimal algaecide concentrations ranging from 0·001 to 0·035%. Guanidine is known to have a high microbicidal effect and is considered to be a new generation microbicidal compound. It is not toxic to human mucous membranes and conjunctivas at low concentrations and has been used as a disinfectant in swimming pools and as an antiseptic for human wounds. The algicidal action of guanidine at low concentrations indicates that it could be an alternative disinfectant or antiseptic for cleaning of the dairy environment and milking equipment, in pre- and postdipping solutions, in the chemical dry therapy of bovine teats and even in the intramammary therapy of P. zopfii infections. This is the first report of the in vitro algicidal effect of guanidine on P. zopfii strains of animal origin. SIGNIFICANCE AND IMPACT OF THE STUDY: Prototheca zopfii genotype 2 is an opportunistic pathogen of bovine mastitis. To date, no effective therapies against protothecal mastitis have been developed. The in vitro algicidal effect of guanidine on 75 P. zopfii genotype 2 strains isolated from cows revealed that all of the isolates were susceptible to the compound at low concentrations, which indicates that guanidine may be used as an antiseptic/disinfectant for dairy milking equipment, in pre- and postdipping solutions, and as a chemical dry therapy or an intramammary therapy. This study describes the in vitro algicidal effect of guanidine on P. zopfii for the first time.


Subject(s)
Guanidine/pharmacology , Mastitis, Bovine/epidemiology , Prototheca/drug effects , Animals , Anti-Infective Agents/pharmacology , Anti-Infective Agents, Local/pharmacology , Cattle , Dairying , Disinfectants/pharmacology , Female , Genotype , Humans , Mastitis, Bovine/drug therapy , Molecular Epidemiology , Prototheca/genetics , Prototheca/isolation & purification
15.
J Mech Behav Biomed Mater ; 69: 144-152, 2017 05.
Article in English | MEDLINE | ID: mdl-28073074

ABSTRACT

Titanium and its alloys are widely used in orthopedic and dental implants, however, some major clinical concerns such as poor wear resistance, lack of bioactivity, and bone resorption due to stress shielding are yet to be overcome. In order to improve these drawbacks, highly porous Ti samples having functionalized surfaces were developed by powder metallurgy with space holder technique followed by anodic treatment. Tribocorrosion tests were performed in 9g/L NaCl solution using a unidirectional pin-on-disc tribometer under 3N normal load, 1Hz frequency and 4mm track diameter. Open circuit potential (OCP) was measured before, during and after sliding. Worn surfaces investigated by field emission gun scanning electron microscope (FEG-SEM) equipped with energy dispersive X-ray spectroscopy (EDS). Results suggested bio-functionalized highly porous samples presented lower tendency to corrosion under sliding against zirconia pin, mainly due to the load carrying effect given by the hard protruded oxide surfaces formed by the anodic treatment.


Subject(s)
Materials Testing , Prostheses and Implants , Titanium/analysis , Alloys , Corrosion , Microscopy, Electron, Scanning , Porosity , Surface Properties
16.
J Dairy Sci ; 99(8): 6436-6445, 2016 Aug.
Article in English | MEDLINE | ID: mdl-27236754

ABSTRACT

Bovine mastitis caused by Prototheca is a serious and complex problem that accounts for high economic losses in the dairy industry. The main objective of this study was to identify and characterize at genetic level different Prototheca strains and provide the most complete data about protothecal antibiotic resistance. The study involves 46 isolates from Italian (13 strains) and Brazilian (33 strains) mastitic milk. These strains were identified by multiplex PCR and single strand conformation polymorphism analysis and characterized by randomly amplified polymorphic DNA (RAPD)-PCR. Moreover, biofilm production and antibiotic susceptibility were evaluated. Forty-two strains resulted as Prototheca zopfii genotype 2, whereas 4 isolates could belong to a potential new Prototheca species. The RAPD-PCR, performed with 3 primers (M13, OPA-4, and OPA-18), showed a notable heterogeneity among isolates and grouped the strains according to the species and geographical origin. Biofilm production was species-dependent and P. zopfii genotype 2 strains were classified as strong biofilm producers. In vitro antibiotic susceptibility tests indicated that Prototheca strains were susceptible to antibacterial drugs belonging to aminoglycosides group; the highest activity against Prototheca strains was observed in the case of colistin sulfate, gentamicin, and netilmicin (100% of susceptible strains). It is interesting to note that all the Italian P. zopfii genotype 2 strains showed lower minimum inhibitory concentration values than the Brazilian ones. Nisin showed more efficacy than lysozyme and potassium sorbate, inhibiting 31% of the strains. Results obtained in this study confirmed that RAPD-PCR is a rapid, inexpensive, and highly discriminating tool for Prototheca strains characterization and could give a good scientific contribution for better understanding the protothecal mastitis in dairy herd.


Subject(s)
Biofilms , Prototheca/genetics , Random Amplified Polymorphic DNA Technique , Animals , Anti-Bacterial Agents , Brazil , Cattle , Italy , Mastitis, Bovine/microbiology , Molecular Typing
17.
J Mech Behav Biomed Mater ; 61: 152-163, 2016 08.
Article in English | MEDLINE | ID: mdl-26866451

ABSTRACT

Poor wear resistance of titanium is a major concern since relative movements due to the cyclic loads in body environment cause wear between the bone and the implant material leading to detachment of the wear debris and release of metal ions due to the simultaneous action of corrosion and wear, defined as tribocorrosion. In order to increase the tribocorrosion resistance, Grade 2 Ti matrix 24vol% B4C particle reinforced composites were processed by hot pressing. Corrosion behaviour was investigated by electrochemical impedance spectroscopy and potentiodynamic polarization in 9g/L NaCl solution at body temperature. Tribocorrosion tests were performed under open circuit potential, as well as under potentiodynamic polarization using a reciprocating ball-on-plate tribometer. Results suggested that the addition of B4C particles provided lower tendency to corrosion and lower corrosion kinetics under sliding, along with significantly reduced wear loss, mainly due to the load carrying effect given by the reinforcement particles.


Subject(s)
Biocompatible Materials/chemistry , Corrosion , Prostheses and Implants , Titanium/chemistry , Materials Testing , Orthopedics
18.
Sci Rep ; 5: 18184, 2015 Dec 08.
Article in English | MEDLINE | ID: mdl-26643808

ABSTRACT

Familial hypercholesterolaemia (FH) is an inherited autosomal dominant disorder resulting from defects in the low-density lipoprotein receptor (LDLR), in the apolipoprotein B (APOB) or in the proprotein convertase subtilisin/kexin type 9 (PCSK9) genes. In the majority of the cases FH is caused by mutations occurring within LDLR, while only few mutations in APOB and PCSK9 have been proved to cause disease. p.(Arg3527Gln) was the first mutation in APOB being identified and characterized. Recently two novel pathogenic APOB variants have been described: p.(Arg1164Thr) and p.(Gln4494del) showing impaired LDLR binding capacity, and diminished LDL uptake. The objective of this work was to analyse the structure of p.(Arg1164Thr) and p.(Gln4494del) variants to gain insight into their pathogenicity. Secondary structure of the human ApoB100 has been investigated by infrared spectroscopy (IR) and LDL particle size both by dynamic light scattering (DLS) and electron microscopy. The results show differences in secondary structure and/or in particle size of p.(Arg1164Thr) and p.(Gln4494del) variants compared with wild type. We conclude that these changes underlie the defective binding and uptake of p.(Arg1164Thr) and p.(Gln4494del) variants. Our study reveals that structural studies on pathogenic variants of APOB may provide very useful information to understand their role in FH disease.


Subject(s)
Amino Acid Substitution , Apolipoproteins B/chemistry , Apolipoproteins B/genetics , Codon , Hyperlipoproteinemia Type II/genetics , Mutation , Apolipoprotein B-100/chemistry , Apolipoprotein B-100/genetics , Apolipoprotein B-100/ultrastructure , Apolipoproteins B/metabolism , Apolipoproteins B/ultrastructure , Cell Line , Humans , Hyperlipoproteinemia Type II/metabolism , Lipoproteins, LDL/chemistry , Lipoproteins, LDL/metabolism , Lipoproteins, LDL/ultrastructure , Lymphocytes/metabolism , Particle Size , Protein Binding , Protein Structure, Secondary
20.
J Dairy Sci ; 98(6): 3706-16, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25828655

ABSTRACT

This study aimed to analyze the chemical composition and the IgG concentration of the colostrum, transitional milk, and mature milk of Santa Inês ewes as well as the transfer of passive immunity to lambs. Thirty-two pregnant ewes and 38 lambs were used. Ewes were milked immediately after lambing and at 12, 24, 36 h and 10 d postpartum. Colostrum was provided to the lambs at 40±15 min (mean±SE) after birth and then at 30-min intervals for obtaining the intake closest to 10% of body weight, and transitional milk was provided ad libitum. Blood from the lambs was collected 36 h after birth for measuring the serum concentrations of IgG, total protein, albumin, and gamma-globulin. The production was lower in primiparous than in multiparous ewes with body condition score (BCS)<2.75, but did not differ between primiparous and multiparous with BCS≥2.75 (interaction parity and BCS). The IgG concentration and fat, protein, lactose, and defatted dry extract percentages were not affected by the BCS of the ewe at lambing or by the parity. The total solids percentage in the colostrum was higher in ewes with BCS<2.75 (interaction BCS and time). The production and the protein, total solid, and defatted dry extract percentages showed quadratic behavior, the fat percentage decreased linearly, and the lactose percentage increased linearly with time postpartum. The IgG concentration in the colostrum was not correlated with the ewe's weight or BCS at the time of lambing. Moreover, the parity, the BCS, the ewe's type of gestation, and the lamb's sex did not influence the serum concentrations of IgG, total protein, albumin, and gamma-globulin in lambs. Adequate passive immune transfer (PIT) was observed in lambs for which the IgG intake was higher than 30 g. Failure in PIT was observed in 39.5% of lambs when considering a serum IgG concentration lower than 15 mg/mL and in 21% when considering a serum total protein concentration lower than 45 mg/mL. The mean apparent efficiency of absorption was 38.10%, with values between 0.02% and 98.80%. The serum IgG concentration was correlated with the total protein concentration (according to the enzymatic colorimetric method), the gamma-globulin concentration, and the absorption efficiency. The extreme variation on apparent efficiency of absorption may have an effect on the success of PIT. Lambs should consume at least 30 g of IgG in the first 24 h of life to ensure adequate PIT.


Subject(s)
Colostrum/immunology , Immunity, Maternally-Acquired/physiology , Immunoglobulin G/chemistry , Milk/chemistry , Sheep/immunology , Animals , Female , Pregnancy , Sheep/physiology , Sheep, Domestic
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