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1.
BMC Psychiatry ; 20(1): 108, 2020 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-32143714

RESUMO

BACKGROUND: Physical inactivity is a key contributor to the global burden of disease and disproportionately impacts the wellbeing of people experiencing mental illness. Increases in physical activity are associated with improvements in symptoms of mental illness and reduction in cardiometabolic risk. Reliable and valid clinical tools that assess physical activity would improve evaluation of intervention studies that aim to increase physical activity and reduce sedentary behaviour in people living with mental illness. METHODS: The five-item Simple Physical Activity Questionnaire (SIMPAQ) was developed by a multidisciplinary, international working group as a clinical tool to assess physical activity and sedentary behaviour in people living with mental illness. Patients with a DSM or ICD mental illness diagnoses were recruited and completed the SIMPAQ on two occasions, one week apart. Participants wore an Actigraph accelerometer and completed brief cognitive and clinical assessments. RESULTS: Evidence of SIMPAQ validity was assessed against accelerometer-derived measures of physical activity. Data were obtained from 1010 participants. The SIMPAQ had good test-retest reliability. Correlations for moderate-vigorous physical activity was comparable to studies conducted in general population samples. Evidence of validity for the sedentary behaviour item was poor. An alternative method to calculate sedentary behaviour had stronger evidence of validity. This alternative method is recommended for use in future studies employing the SIMPAQ. CONCLUSIONS: The SIMPAQ is a brief measure of physical activity and sedentary behaviour that can be reliably and validly administered by health professionals.


Assuntos
Exercício Físico , Transtornos Mentais , Comportamento Sedentário , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Inquéritos e Questionários , Adulto Jovem
2.
Mycopathologia ; 184(6): 775-786, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31679132

RESUMO

Candida can adhere and form biofilm on biomaterials commonly used in medical devices which is a key attribute that enhances its ability to cause infections in humans. Furthermore, biomaterial-related infections represent a major therapeutic challenge since Candida biofilms are implicated in antifungal therapies failure. The goals of the present work were to investigate the effect of three 5-aminoimidazole-4-carbohydrazonamides, namely (Z)-5-amino-1-methyl-N'-aryl-1H-imidazole-4-carbohydrazonamides [aryl = phenyl (1a), 4-fluorophenyl (1b), 3-fluorophenyl (1c)], on Candida albicans and Candida krusei biofilm on nanohydroxyapatite substrate, a well-known bioactive ceramic material. To address these goals, both quantitative methods (by cultivable cell numbers) and qualitative evaluation (by scanning electron microscopy) were used. Compounds cytocompatibility towards osteoblast-like cells was also evaluated after 24 h of exposure, through resazurin assay. The three tested compounds displayed a strong inhibitory effect on biofilm development of both Candida species as potent in vitro activity against C. albicans sessile cells. Regarding cytocompatibility, a concentration-dependent effect was observed. Together, these findings indicated that the potent activity of imidazole derivatives on Candida spp. biofilms on nanohydroxyapatite substrate, in particular compound 1c, is worth further investigating.


Assuntos
Antifúngicos/farmacologia , Biofilmes/efeitos dos fármacos , Candida , Próteses e Implantes/microbiologia , Infecções Relacionadas à Prótese/tratamento farmacológico , Materiais Biocompatíveis , Biofilmes/crescimento & desenvolvimento , Candida/efeitos dos fármacos , Candida/crescimento & desenvolvimento , Candida albicans/efeitos dos fármacos , Candida albicans/crescimento & desenvolvimento , Linhagem Celular/efeitos dos fármacos , Humanos , Imidazóis/farmacologia , Testes de Sensibilidade Microbiana , Microscopia Eletrônica de Varredura , Osteoblastos/efeitos dos fármacos , Infecções Relacionadas à Prótese/microbiologia
3.
Biochim Biophys Acta ; 1860(4): 825-35, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26801877

RESUMO

BACKGROUND: Surface topography is a key parameter in bone cells-biomaterials interactions. This study analyzed the behavior of human osteoclast precursor cells cultured over three hydroxyapatite (HA) surfaces ranging from a micro- to nanoscale topography. METHODS: HA surfaces were prepared with microsized HA particles, at 1300°C (HA1), and with nanosized HA particles at 1000°C (HA2) and 830°C (HA3). Human osteoclast precursors were cultured in the absence or presence of M-SCF and RANKL. RESULTS: HA surfaces had similar chemical composition, however, HA1 and HA3 presented typical micro- and nanostructured topographies, respectively, and HA2 profile was between those of HA1 and HA3. The decrease on the average grain diameter to the nanoscale range (HA3) was accompanied by an increase in surface area, porosity and hydrophilicity and a decrease in roughness. Compared to HA1 surface, HA3 allowed a lower osteoclastic adhesion, differentiation and function. Differences in the cell response appeared to be associated with the modulation of relevant intracellular signaling pathways. CONCLUSIONS: The decrease in HA grain size to a biomimetic nanoscale range, appears less attractive to osteoclastic differentiation and function, compared to the HA microsized topography. GENERAL SIGNIFICANCE: This observation emphasizes the role of surface topography in designing advanced biomaterials for tailored bone cells response in regenerative strategies.


Assuntos
Materiais Biocompatíveis/farmacologia , Diferenciação Celular/efeitos dos fármacos , Durapatita/farmacologia , Osteoclastos/metabolismo , Transdução de Sinais/efeitos dos fármacos , Células-Tronco/metabolismo , Adulto , Materiais Biocompatíveis/química , Durapatita/química , Feminino , Humanos , Masculino , Osteoclastos/citologia , Células-Tronco/citologia , Propriedades de Superfície
4.
Biologicals ; 48: 6-9, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28666718

RESUMO

Brucellosis remains as a major infectious disease of domestic animals and is considered a re-emerging zoonosis in several countries. B. abortus infections in bulls are related to reproductive tract infections, although infected animals show transient serological titers or nonreactor status. Thus, diagnosis of bovine brucellosis based exclusively on serological tests probably underestimates B. abortus infections in bulls. In this scenario, three hundred thirty-five serum samples from reproductively mature bovine bulls were subjected simultaneously to standard serodiagnosis using the rose Bengal test (RBT), 2-mercaptoethanol (2-ME), complement fixation (CFT), and fluorescence polarization assay (FPA). Furthermore, conventional semen plasma agglutination (SPA) and modified 2-ME, FC and, FPA were carried out in all bulls replaing serum by seminal plasma. Semen from all bulls was also analyzed for sperm viability, microbiological culture in Farrell media, and polymerase chain reaction (PCR). Only eight (2.38%) semen samples were considered improper for reproduction services (necrospermia and azoospermia), although none of these animals was positive in any of the diagnosis methods used. Five bulls (1.49%) were simultaneously positive in conventional RBT, 2-ME, SPA, modified 2-ME, microbiological culture in Farrell media, and in PCR for B. abortus strain 19. Two (1.67%) bulls were positive in PCR for B. abortus field strains and negative in all other tests, although semen was considered viable to reproduction service. The identification of B. abortus B19 strain in serum and semen of bulls occurred probably due to improper vaccination of males or infection by B19 strain shedding by vaccinated females that could to contaminated environment of farms. In addition, detection of B. abortus field strains only using PCR in bulls without sperm viability abnormalities indicate the need for including molecular methods to improve diagnosis of the disease in bovine bulls.


Assuntos
Brucella abortus , Brucelose Bovina/sangue , Brucelose Bovina/microbiologia , Sêmen/microbiologia , Animais , Bovinos , Masculino
5.
Reprod Domest Anim ; 52(5): 905-910, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28543808

RESUMO

Cryopreservation causes damage to spermatozoa, and methods minimizing this damage are therefore needed. Although much discussed, seminal plasma removal has become an alternative to improve sperm quality and viability after freezing and has been applied to different species in attempt to obtain good results. The objective of this study was to evaluate semen quality in buffaloes submitted to two methods for seminal plasma removal (filtration and centrifugation). Semen samples were collected from seven Murrah buffalo bulls (Bubalus bubalis) once a week for 8 weeks. Each ejaculate was divided into three groups: control (presence of seminal plasma), centrifugation and filtration. Sperm kinetics was evaluated with the computer-assisted sperm analysis (CASA) system. Plasmalemma and acrosomal membrane integrity, mitochondrial membrane potential and reactive oxygen species (ROS) were measured by flow cytometry, and lipid peroxidation was evaluated by the thiobarbituric acid reactive substances (TBARS) assay. Seminal plasma removal did not improve sperm kinetics compared to the control group. Centrifugation increased the number of cells with damaged acrosomal membranes (0.77 ± 0.05) and filtration caused greater plasmalemma and acrosomal membrane damage (22.18 ± 1.07). No difference in the mitochondrial membrane potential was observed between groups. In contrast, ROS production was higher in the centrifugation group compared to the control and filtration groups, although no differences in TBARS formation were detected. In conclusion, seminal plasma removal did not improve the quality of thawed buffalo semen compared to control in terms of sperm kinetics, membrane integrity, mitochondrial membrane potential or lipid peroxidation.


Assuntos
Búfalos , Criopreservação/veterinária , Preservação do Sêmen/veterinária , Sêmen , Animais , Centrifugação , Criopreservação/métodos , Filtração/veterinária , Masculino , Análise do Sêmen , Preservação do Sêmen/métodos , Motilidade dos Espermatozoides
6.
Phys Rev Lett ; 117(7): 070404, 2016 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-27563941

RESUMO

We demonstrate the violation of an Einstein-Podolsky-Rosen steering inequality developed for single-photon path entanglement with displacement-based detection. We use a high-rate source of heralded single-photon path-entangled states, combined with high-efficiency superconducting-based detectors, in a scheme that is free of any postselection and thus immune to the detection loophole. This result conclusively demonstrates single-photon entanglement in a one-sided device-independent scenario, and opens the way towards implementations of device-independent quantum technologies within the paradigm of path entanglement.

7.
Phys Rev Lett ; 114(17): 170504, 2015 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-25978215

RESUMO

How can one detect entanglement between multiple optical paths sharing a single photon? We address this question by proposing a scalable protocol, which only uses local measurements where single photon detection is combined with small displacement operations. The resulting entanglement witness does not require postselection, nor assumptions about the photon number in each path. Furthermore, it guarantees that entanglement lies in a subspace with at most one photon per optical path and reveals genuinely multipartite entanglement. We demonstrate its scalability and resistance to loss by performing various experiments with two and three optical paths. We anticipate applications of our results for quantum network certification.

8.
Nanotechnology ; 26(31): 315101, 2015 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-26180062

RESUMO

Ceramic scaffolds are widely studied in the bone tissue engineering field due to their potential in regenerative medicine. However, adhesion of microorganisms on biomaterials with subsequent formation of antibiotic-resistant biofilms is a critical factor in implant-related infections. Therefore, new strategies are needed to address this problem. In the present study, three-dimensional and interconnected porous granules of nanostructured hydroxyapatite (nanoHA) incorporated with different amounts of zinc oxide (ZnO) nanoparticles were produced using a simple polymer sponge replication method. As in vitro experiments, granules were exposed to Staphylococcus aureus and Staphylococcus epidermidis and, after 24 h, the planktonic and sessile populations were assessed. Cytocompatibility towards osteoblast-like cells (MG63 cell line) was also evaluated for a period of 1 and 3 days, through resazurin assay and imaging flow cytometry analysis. As in vivo experiments, nanoHA porous granules with and without ZnO nanoparticles were implanted into the subcutaneous tissue in rats and their inflammatory response after 3, 7 and 30 days was examined, as well as their antibacterial activity after 1 and 3 days of S. aureus inoculation. The developed composites proved to be especially effective at reducing bacterial activity in vitro and in vivo for a weight percentage of 2% ZnO, with a low cell growth inhibition in vitro and no differences in the connective tissue growth and inflammatory response in vivo. Altogether, these results suggest that nanoHA-ZnO porous granules have a great potential to be used in orthopaedic and dental applications as a template for bone regeneration and, simultaneously, to restrain biomaterial-associated infections.


Assuntos
Antibacterianos/farmacologia , Materiais Biocompatíveis/toxicidade , Nanopartículas/química , Nanopartículas/microbiologia , Nanoporos , Osteoblastos/microbiologia , Animais , Linhagem Celular , Durapatita/química , Humanos , Técnicas In Vitro , Masculino , Nanoporos/ultraestrutura , Osteoblastos/efeitos dos fármacos , Porosidade , Ratos , Ratos Wistar , Infecções Estafilocócicas , Óxido de Zinco/química , Óxido de Zinco/farmacologia
9.
Genet Mol Res ; 14(4): 14076-87, 2015 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-26535722

RESUMO

The effect of selection for postweaning weight was evaluated within the growth curve parameters for both growth and carcass traits. Records of 2404 Nellore animals from three selection lines were analyzed: two selection lines for high postweaning weight, selection (NeS) and traditional (NeT); and a control line (NeC) in which animals were selected for postweaning weight close to the average. Body weight (BW), hip height (HH), rib eye area (REA), back fat thickness (BFT), and rump fat thickness (RFT) were measured and records collected from animals 8 to 20 (males) and 11 to 26 (females) months of age. The parameters A (asymptotic value) and k (growth rate) were estimated using the nonlinear model procedure of the Statistical Analysis System program, which included fixed effect of line (NeS, NeT, and NeC) in the model, with the objective to evaluate differences in the estimated parameters between lines. Selected animals (NeS and NeT) showed higher growth rates than control line animals (NeC) for all traits. Line effect on curves parameters was significant (P < 0.001) for BW, HH, and REA in males, and for BFT and RFT in females. Selection for postweaning weight was effective in altering growth curves, resulting in animals with higher growth potential.


Assuntos
Bovinos/crescimento & desenvolvimento , Ultrassonografia/veterinária , Animais , Peso Corporal , Pesos e Medidas Corporais/métodos , Pesos e Medidas Corporais/veterinária , Cruzamento/métodos , Bovinos/genética , Feminino , Masculino , Dinâmica não Linear , Fenótipo , Seleção Genética , Ultrassonografia/métodos
10.
Genet Mol Res ; 14(4): 14999-5007, 2015 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-26634461

RESUMO

Complete blood counts and blood biochemical analyses are laboratory tests that allow the monitoring of physiological condition, nutrition, and health in free-living or captive wild animals. When interpreting these tests, it is essential to compare the results with reference ranges that are suitable for the species. Few studies have been conducted on the hematological and biochemical characteristics of Tayassu tajacu, particularly for animals raised in the Amazon biome. The objectives of this study were to evaluate the influence of age and gender on the hematological and biochemical profiles of captive T. tajacu, and to establish reference intervals for these parameters. Complete blood counts and biochemical analyses were performed using manual methods and semi-automatic equipment, respectively. There were significant differences in relation to age in hematocrit and hemoglobin levels, and mean cell volumes, in captive T. tajacu. No basophils were observed, and the neutrophil:lymphocyte ratio was less than 1. Levels of total protein, urea, phosphorus, and alkaline phosphatase were significantly affected by age (P < 0.05). Gender did not affect any of the results. The hematological and biochemical parameters for this species were determined, and may be used as reference ranges for captive T. tajacu.


Assuntos
Artiodáctilos/sangue , Animais , Animais Selvagens , Artiodáctilos/metabolismo , Biomarcadores/sangue , Biomarcadores/metabolismo , Contagem de Células Sanguíneas/veterinária , Brasil , Feminino , Testes Hematológicos/veterinária , Masculino , Valores de Referência
11.
Opt Express ; 22(4): 4371-8, 2014 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-24663760

RESUMO

We demonstrate a compact photon pair source based on a periodically poled lithium niobate nonlinear crystal in a short cavity. This approach provides efficient, low-loss, mode selection that is compatible with standard telecommunication networks. Photons with a coherence time of 8.6 ns (116 MHz) are produced and their purity is demonstrated. A source brightness of 134 pairs (s. mW. MHz)(-1) is reported. The cavity parameters are chosen such that the photon pair modes emitted can be matched to telecom ultra dense wavelength division multiplexing (U-DWDM) channel spacings. The high level of purity and compatibility with standard telecom networks is of great importance for complex quantum communication networks.

12.
J Investig Allergol Clin Immunol ; 24(3): 184-91, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25011356

RESUMO

BACKGROUND: Severe combined immunodeficiency (SCID) is one of the most severe forms of primary immunodeficiency. The objectives of this study were to analyze the diagnosis, treatment, and prognosis of SCID in Brazil and to document the impact of BCG vaccine. METHODS: We actively searched for cases by contacting all Brazilian referral centers. RESULTS: We contacted 23 centers and 70 patients from 65 families. Patients were born between 1996 and 2011, and 49 (70%) were male. More than half (39) of the diagnoses were made after 2006. Mean age at diagnosis declined from 9.7 to 6.1 months (P = .058) before and after 2000, respectively, and mean delay in diagnosis decreased from 7.9 to 4.2 months (P = .009). Most patients (60/70) were vaccinated with BCG before the diagnosis, 39 of 60 (65%) had complications related to BCG vaccine, and the complication was disseminated in 29 of 39 (74.3%). Less than half of the patients (30, 42.9%) underwent hematopoietic stem cell transplantation (HSCT). Half of the patients died (35, 50%), and 23 of these patients had not undergone HSCT. Disseminated BCG was the cause of death, either alone or in association with other causes, in 9 of 31 cases (29%, no data for 4 cases). CONCLUSIONS: In Brazil, diagnosis of SCID has improved over the last decade, both in terms of the number of cases and age at diagnosis, although a much higher number of cases had been expected. Mortality is higher than in developed countries. Complications of BCG vaccine are an important warning sign for the presence of SCID and account for significant morbidity during disease progression.


Assuntos
Vacina BCG/efeitos adversos , Imunodeficiência Combinada Severa/terapia , Adolescente , Brasil/epidemiologia , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Prognóstico , Imunodeficiência Combinada Severa/complicações , Imunodeficiência Combinada Severa/epidemiologia
13.
Front Bioeng Biotechnol ; 12: 1355950, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39139296

RESUMO

The most recent progress in reconstructive therapy for the management of periodontitis and peri-implantitis bone defects has relied on the development of highly porous biodegradable bioaerogels for guided bone regeneration. The objective of this work was to evaluate in vitro the osteoinduction of periodontal-originating cells (human dental follicle mesenchymal cells, DFMSCs) promoted by a nano-hydroxyapatite/chitosan (nHAp/CS) bioaerogel, which was purified and sterilized by a sustainable technique (supercritical CO2). Moreover, the in vivo bone regeneration capacity of the nHAp/CS bioaerogel was preliminarily assessed as a proof-of-concept on a rat calvaria bone defect model. The quantification of DNA content of DFMSCs seeded upon nHAp/CS and CS scaffolds (control material) showed a significant increase from the 14th to the 21st day of culture. These results were corroborated through confocal laser scanning microscopy analysis (CLSM). Furthermore, the alkaline phosphatase (ALP) activity increased significantly on the 21st day, similarly for both materials. Moreover, the presence of nHAp promoted a significantly higher expression of osteogenic genes after 21 days when compared to CS scaffolds and control. CLSM images of 21 days of culture also showed an increased deposition of OPN over the nHAp/CS surface. The in vivo bone formation was assessed by microCT and histological analysis. The in vivo evaluation showed a significant increase in bone volume in the nHAp/CS test group when compared to CS and the empty control, as well as higher new bone formation and calcium deposition within the nHAp/CS structure. Overall, the present study showed that the nHAp/CS bioaerogel could offer a potential solution for periodontal and peri-implant bone regeneration treatments since the in vitro results demonstrated that it provided favorable conditions for DFMSC proliferation and osteogenic differentiation, while the in vivo outcomes confirmed that it promoted higher bone ingrowth.

14.
J Med Primatol ; 42(2): 71-8, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23278502

RESUMO

BACKGROUND: The aim of this study was to identify the aerobic bacteria of the preputial and vaginal microbiota in owl monkeys that have been raised in captivity and to evaluate the antimicrobial susceptibility of these bacteria by gender and social organization. METHODS: Thirty clinically healthy Aotus azarai infulatus were used. A total of 134 samples were collected, 60 from the preputial mucosa and 74 from the vaginal mucosa. An automated system of bacterial identification was used. RESULTS AND CONCLUSIONS: Staphylococcus intermedius and Proteus mirabilis were the microorganisms that were most frequently identified according to gender and social organization. The antimicrobial susceptibility of the isolated gram-positive bacteria was similar in both sexes. However, the gram-negative strains had some differences. The aerobic bacterial population of the vaginal and preputial microbiota is similar in owl monkeys, and there are no differences in the number and bacterial species according to sex and social organization.


Assuntos
Aotidae/microbiologia , Pênis/microbiologia , Vagina/microbiologia , Animais , Feminino , Bactérias Gram-Positivas/efeitos dos fármacos , Bactérias Gram-Positivas/isolamento & purificação , Masculino , Metagenoma , Testes de Sensibilidade Microbiana , Modelos Animais , Mucosa/microbiologia , Proteus mirabilis/efeitos dos fármacos , Proteus mirabilis/isolamento & purificação , Comportamento Sexual Animal , Staphylococcus intermedius/efeitos dos fármacos
15.
Eur J Paediatr Dent ; 24(2): 112-123, 2023 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-37038757

RESUMO

Aim: The present study aimed: i) to retrospectively evaluate the expansion movement predicted by the Clincheck® software and the achieved expansion using Invisalign First® in children needing maxillary expansion to correct malocclusions; and ii) to critically compare these clinical results with the outcomes obtained for maxillary expansion using conventional removable and cemented expanders. Material and Methods: The 3D digital models of the dental arches of 24 children undergoing orthodontic treatment exclusively with Invisalign First® aligners between 2018 and 2021 were sequentially selected for this study. Three digital models were analysed: pre-treatment (P0), the Clincheck®-predicted tooth positions (P1), and post-treatment (P2) models. The maxillary dental arch width and expansion efficiency were measured andcalculated. An in-depth review of the available literature on maxillary expansion was performed following PRISMA guidelines. Results: Invisalign First® was able to achieve a total effectiveness of maxillary expansion of 62.6%, compared to the predicted movement. Similarly, the total effectiveness of mandibular expansion was 61.6%. Conclusions: Our data shows that Invisalign First® system can increase the arch width with maxillary expansion effectiveness, providing similar results to those achieved with conventional removable appliances. However, neither Invisalign First® aligners nor conventional removable expanders are as much efficient as cemented-retained appliances.


Assuntos
Má Oclusão , Aparelhos Ortodônticos Removíveis , Criança , Humanos , Estudos Retrospectivos , Técnicas de Movimentação Dentária , Resultado do Tratamento , Dentição Mista , Má Oclusão/terapia
16.
J Mol Model ; 29(7): 215, 2023 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-37347316

RESUMO

CONTEXT: Recently, a new 2D carbon allotrope named biphenylene network (BPN) was experimentally realized. Here, we use density functional theory (DFT) calculations to study its boron nitride analogue sheet's structural, electronic, and optical properties (BN-BPN). Results suggest that BN-BPN has good structural and dynamic stabilities. It also has a direct bandgap of 4.5 eV and significant optical activity in the ultraviolet range. BN-BPN Young's modulus varies between 234.4[Formula: see text]273.2 GPa depending on the strain direction. METHODS: Density functional theory (DFT) simulations for the electronic and optical properties of BN-BPN were performed using the CASTEP package within the Biovia Materials Studio software. The exchange and correlation functions are treated within the generalized gradient approximation (GGA) as parameterized by Perdew-Burke-Ernzerhof (PBE) and the hybrid functional Heyd-Scuseria-Ernzerhof (HSE06). For convenience, the mechanical properties were carried out using the DFT approach implemented in the SIESTA code, also within the scope of the GGA/PBE method. We used the double-zeta plus polarization (DZP) for the basis set in these cases. Moreover, the norm-conserving Troullier-Martins pseudopotential was employed to describe the core electrons.


Assuntos
Carbono , Eletrônica , Módulo de Elasticidade , Elétrons
17.
Int J Obes (Lond) ; 36(8): 1032-9, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21986708

RESUMO

BACKGROUND/OBJECTIVES: Serum amyloid A (SAA) is an acute-phase protein that has been recently correlated with obesity and insulin resistance. Therefore, we first examined whether human recombinant SAA (rSAA) could affect the proliferation, differentiation and metabolism of 3T3-L1 preadipocytes. DESIGN: Preadipocytes were treated with rSAA and analyzed for changes in viability and [³H-methyl]-thymidine incorporation as well as cell cycle perturbations using flow cytometry analysis. The mRNA expression profiles of adipogenic factors during the differentiation protocol were also analyzed using real-time PCR. After differentiation, 2-deoxy-[1,2-³H]-glucose uptake and glycerol release were evaluated. RESULTS: rSAA treatment caused a 2.6-fold increase in cell proliferation, which was consistent with the results from flow cytometry showing that rSAA treatment augmented the percentage of cells in the S phase (60.9±0.54%) compared with the control cells (39.8±2.2%, (***) P<0.001). The rSAA-induced cell proliferation was mediated by the ERK1/2 signaling pathway, which was assessed by pretreatment with the inhibitor PD98059. However, the exposure of 3T3-L1 cells to rSAA during the differentiation process resulted in attenuated adipogenesis and decreased expression of adipogenesis-related factors. During the first 72 h of differentiation, rSAA inhibited the differentiation process by altering the mRNA expression kinetics of adipogenic transcription factors and proteins, such as PPARγ2 (peroxisome proliferator-activated receptor γ 2), C/EBPß (CCAAT/enhancer-binding protein ß) and GLUT4. rSAA prevented the intracellular accumulation of lipids and, in fully differentiated cells, increased lipolysis and prevented 2-deoxy-[1,2-³H]-glucose uptake, which favors insulin resistance. Additionally, rSAA stimulated the secretion of proinflammatory cytokines interleukin 6 and tumor necrosis factor α, and upregulated SAA3 mRNA expression during adipogenesis. CONCLUSIONS: We showed that rSAA enhanced proliferation and inhibited differentiation in 3T3-L1 preadipocytes and altered insulin sensitivity in differentiated cells. These results highlight the complex role of SAA in the adipogenic process and support a direct link between obesity and its co-morbidities such as type II diabetes.


Assuntos
Células 3T3-L1/metabolismo , Adipócitos/metabolismo , Desoxiglucose/metabolismo , Resistência à Insulina , RNA Mensageiro/metabolismo , Proteína Amiloide A Sérica/metabolismo , Animais , Diferenciação Celular/genética , Proliferação de Células , Citometria de Fluxo , Humanos , Resistência à Insulina/genética , Peptídeos e Proteínas de Sinalização Intercelular , Camundongos , Camundongos Obesos , Reação em Cadeia da Polimerase em Tempo Real , Proteína Amiloide A Sérica/genética , Regulação para Cima
18.
Geobiology ; 20(1): 41-59, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34291867

RESUMO

The 2-methylhopanes (2-MeHops) are molecular fossils of 2-methylbacteriohopanepolyols (2-MeBHPs) and among the oldest biomarkers on Earth. However, these biomarkers' specific sources are currently unexplained, including whether they reflect an expansion of marine cyanobacteria. Here, we study the occurrence of 2-MeBHPs and the genes involved in their synthesis in modern bacteria and explore the occurrence of 2-MeHops in the geological record. We find that the gene responsible for 2-MeBHP synthesis (hpnP) is widespread in cyano- and ⍺-proteobacteria, but absent or very limited in other classes/phyla of bacteria. This result is consistent with the dominance of 2-MeBHP in cyano- and ⍺-proteobacterial cultures. The review of their geological occurrence indicates that 2-MeHops are found from the Paleoproterozoic onwards, although some Precambrian samples might be biased by drilling contamination. During the Phanerozoic, high 2-MeHops' relative abundances (index >15%) are associated with climatic and biogeochemical perturbations such as the Permo/Triassic boundary and the Oceanic Anoxic Events. We analyzed the modern habitat of all hpnP-containing bacteria and find that the only one species coming from an undisputed open marine habitat is an ⍺-proteobacterium acting upon the marine nitrogen cycle. Although organisms can change their habitat in response to environmental stress and evolutionary pressure, we speculate that the high sedimentary 2-MeHops' occurrence observed during the Phanerozoic reflect ⍺-proteobacteria expansion and marine N-cycle perturbations in response to climatic and environmental change.


Assuntos
Cianobactérias , Triterpenos , Evolução Biológica , Cianobactérias/genética , Fósseis , Geologia
19.
Int J Pharm ; 622: 121832, 2022 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-35595042

RESUMO

New strategies for the treatment of polymicrobial bone infections are required. In this study, the co-delivery of two antimicrobials by poly(D,L-lactic acid) (PDLLA) scaffolds was investigated in a polymicrobial biofilm model. PDLLA scaffolds were prepared by solvent casting/particulate leaching methodology, incorporating minocycline and voriconazole as clinically relevant antimicrobial agents. The scaffolds presented a sponge-like appearance, suitable to support cell proliferation and drug release. Single- and dual-species biofilm models of Staphylococcus aureus and Candida albicans were developed and characterized. S. aureus presented a higher ability to form single-species biofilms, compared to C. albicans. Minocycline and voriconazole-loaded PDLLA scaffolds showed activity against S. aureus and C. albicans single- and dual-biofilms. Ultimately, the cytocompatibility/functional activity of PDLLA scaffolds observed in human MG-63 osteosarcoma cells unveil their potential as a next-generation co-delivery system for antimicrobial therapy in bone infections.


Assuntos
Anti-Infecciosos , Staphylococcus aureus Resistente à Meticilina , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Biofilmes , Candida albicans , Humanos , Ácido Láctico , Testes de Sensibilidade Microbiana , Minociclina , Staphylococcus aureus , Voriconazol
20.
Animal ; 16(12): 100678, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36493570

RESUMO

In an attempt to develop accessible methods for the precocious individual selection based on phenotypic attributes related to reproductive superiority, this study evaluated the effects of follicular wave stages (emergence and dominance) and the repeatability coefficients of potential fertility predictors (vulvar morphometry, uterine biometry, echogenicity and echotexture, ovarian biometry, and antral follicle count - AFC) in two breeds of purebred prepubertal heifers. Nellore (n = 30) and Caracu (n = 28) heifers were submitted to a sequence of 11 evaluations conducted every 48 h (D0 - random day of the antral follicular wave until D20) to study potential fertility indicators under natural conditions. The data obtained were compared according to breed and follicular wave stage. Statistical analysis included the fixed effects of breed, evaluation day, and their statistical interaction and was performed using MIXED, GENMOD, GLM, and CORR procedures of the SAS program. Breed was found to influence rima height, ovarian area, and AFC, which were greater in Nellore heifers (P < 0.02). The follicular wave stage also influenced most of the potential predictors, highlighting AFC which was higher in the presence of a dominant follicle in both breeds (P < 0.0001). The repeatability coefficients for vulvar width (0.76 and 0.66), ovarian area (0.70 and 0.62), and AFC (0.76 and 0.74) were considered to be high in Nellore and Caracu heifers, respectively. Only ovarian biometry was able to predict AFC (Pearson correlation coefficient ≥ 0.66; P < 0.0001) in prepubertal heifers. The results indicate that most of the phenotypic reproductive parameters analyzed can be characterized throughout prepuberty using a single measure since they are intrinsic attributes of the individual.


Assuntos
Fertilidade , Folículo Ovariano , Bovinos , Feminino , Animais , Folículo Ovariano/diagnóstico por imagem , Ovário , Projetos de Pesquisa , Reprodução
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