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3.
Acta Orthop Belg ; 89(1): 45-50, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37294984

RESUMO

The objective of the present study is to perform a systematic review with meta-analysis of the literature on treatment of developmental dysplasia of the hip (DDH) in patients over eight years of age to provide better understanding of therapeutic strategies and results. Authors carried out a systematic review and metanalysis of the literature on DDH treated in patients aged eight years of age or older. A literature search was carefully performed from June 2019 to June 2020. The articles had to report one stage reconstructive surgical treatment of DDH for patients eight years or older, presenting clinical and radiographic evaluation according to the Tonnis and Severin, and McKay systems. Meta-analysis was carried out using the software metanalyst to perform the pooled effect size Nine studies met the inclusion criteria. They assessed a total of 234 patients and 266 hips. Female patients accounted for 75.7% (eight unknown) and the follow-up ranged from 1 to 17.4 years. The majority of the procedures included an acetabular surgery (93.9%) while femoral shortening was performed in 78%. Acceptable outcomes were found in between 67% (Mckay system) and 91% (Severin system) of the cases. Femoral varus and derrotation shortening associated with redirectional osteotomy of the acetabulum (for those with closed triradiate cartilage) or acetabular redirection/reshaping were the most prevalent combined procedures; this strategy can lead to 60% of acceptable clinical results and 90% of radiographically acceptable results. Therefore, our findings give credence to the recommendation for the treatment of DDH in patients over eight years old.


Assuntos
Displasia do Desenvolvimento do Quadril , Luxação Congênita de Quadril , Humanos , Feminino , Criança , Luxação Congênita de Quadril/diagnóstico por imagem , Luxação Congênita de Quadril/cirurgia , Displasia do Desenvolvimento do Quadril/diagnóstico por imagem , Displasia do Desenvolvimento do Quadril/cirurgia , Displasia do Desenvolvimento do Quadril/complicações , Resultado do Tratamento , Estudos Retrospectivos , Acetábulo/diagnóstico por imagem , Acetábulo/cirurgia
9.
Biomed Mater Eng ; 31(3): 191-201, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32568169

RESUMO

OBJECTIVE: The main goal of this study was to examine the influence of hydroxyapatite (HAp) macroaggreate concentrations on thermal and mechanical properties of radioactive bone cement and to study the relation of glass transition Tg with its mechanical properties. METHODS: The bone cement as (1-x)PMMA-xHAp binary system was prepared in six [x] distinct concentration parameters of 0.0 up to 0.5. The HAp was synthesized using a solgel procedure following calcination by thermal treatment. The composite was prepared in cold based (non-radioactive) mixing polymethyl methacrylate (PMMA) and HAp. Differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and mechanical compressive strength (CS) were used to measure the thermal and mechanical properties. RESULTS: The DSC and TGA thermal profiles in function to concentration parameter [x] were presented. The CS lies in a range of 3.71-7.37 MPa and the glass transition temperature Tg = 126.27 °C. There was a direct relationship between the PMMA-HAp thermoplastic properties with mechanical and thermal properties in function of HAp concentrations. CONCLUSION: The specific PMMA-HAp composite, with a concentration ratio of 1:1 and HAp thermal treatment at the Tg, provides a material with a compression strength of 7.37 MPa and a suitable amount of porous similar to a trabecular bone, possible to apply in bone cement implants, regardless of whether they are radioactive or not.


Assuntos
Fenômenos Biomecânicos/efeitos dos fármacos , Substitutos Ósseos/química , Durapatita/farmacologia , Polimetil Metacrilato/química , Materiais Biocompatíveis/síntese química , Materiais Biocompatíveis/química , Materiais Biocompatíveis/uso terapêutico , Cimentos Ósseos/síntese química , Cimentos Ósseos/química , Cimentos Ósseos/uso terapêutico , Substitutos Ósseos/síntese química , Substitutos Ósseos/uso terapêutico , Força Compressiva/efeitos dos fármacos , Durapatita/química , Humanos , Hidroxiapatitas/química , Hidroxiapatitas/uso terapêutico , Teste de Materiais , Polimetil Metacrilato/síntese química , Polimetil Metacrilato/uso terapêutico , Porosidade/efeitos dos fármacos , Estresse Mecânico , Resistência à Tração/efeitos dos fármacos , Termogravimetria , Vitrificação/efeitos dos fármacos
10.
Food Chem Toxicol ; 136: 111076, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31883990

RESUMO

Thymoquinone (TQ) is a monoterpene isolated from the oil of Nigella sativa seeds. The aim of this work was to evaluate the cytotoxic effects induced by TQ and its impact on the migration and invasion potential of 786-O human renal cancer cells. These cells were exposed to TQ (1-100 µM) for 24 and 48 h and cell viability assessed using the Crystal Violet and MTS assays. TQ treatment clearly decreased cell viability in a concentration- and time-dependent manner. TQ exposure moderately increased intracellular ROS levels and co-incubation with reduced glutathione markedly increased cell viability. Moreover, the effect of TQ in the cell cycle distribution was evaluated using flow cytometry, and an increase in the sub-G1 population was observed, especially at 30 µM, along with an increase in the % of apoptotic cells. TQ did not show genotoxic effects at a non-cytotoxic concentration (1.0 µM). At this concentration level, TQ significantly decreased the collective migration of 786-O cells, whereas it had no effect in chemotactic migration. TQ also decreased the invasiveness potential of 786-O cells, as evaluated by the transwell invasion assay. Overall, these results suggest that TQ presents an anticancer potential in the context of renal cancer, warranting further investigation.


Assuntos
Antineoplásicos/farmacologia , Benzoquinonas/farmacologia , Medicamentos de Ervas Chinesas/farmacologia , Nigella sativa/química , Antineoplásicos/análise , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Medicamentos de Ervas Chinesas/análise , Humanos , Neoplasias Renais/tratamento farmacológico , Neoplasias Renais/fisiopatologia
11.
Sci Adv ; 5(4): eaav4310, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-31001586

RESUMO

Anaerobic ammonium oxidation (anammox) is a major process in the biogeochemical nitrogen cycle in which nitrite and ammonium are converted to dinitrogen gas and water through the highly reactive intermediate hydrazine. So far, it is unknown how anammox organisms convert the toxic hydrazine into nitrogen and harvest the extremely low potential electrons (-750 mV) released in this process. We report the crystal structure and cryo electron microscopy structures of the responsible enzyme, hydrazine dehydrogenase, which is a 1.7 MDa multiprotein complex containing an extended electron transfer network of 192 heme groups spanning the entire complex. This unique molecular arrangement suggests a way in which the protein stores and releases the electrons obtained from hydrazine conversion, the final step in the globally important anammox process.


Assuntos
Proteínas de Bactérias/química , Heme/química , Oxirredutases/química , Proteínas de Bactérias/metabolismo , Sítios de Ligação , Domínio Catalítico , Microscopia Crioeletrônica , Cristalografia por Raios X , Transporte de Elétrons , Bactérias Gram-Negativas/enzimologia , Oxirredutases/metabolismo , Estrutura Quaternária de Proteína
12.
Plant Biol (Stuttg) ; 21(1): 142-149, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30216618

RESUMO

Loss and fragmentation of native vegetation negatively affect crop pollinators and productivity of several crop species. The yellow passion fruit is an excellent model to investigate this issue, because its main pollinators are sensitive to deforestation. Seasonality also influences fruit set of crop species that are pollinated by bees. Climate determines plant flowering patterns and consequently affects pollinator activity. Little is known on effects of pollinators on crop quality in general, and particularly of many tropical fruits that have multiple fruiting seasons throughout the year, such as passion fruit. Our hypothesis is that the distance to the native vegetation and climate seasonality affect the pollination and fruit production of cultivated, hermaphrodite, self-incompatible, protandrous species that depend on large-sized bees to set fruit. We observed flowers of the yellow passion fruit in eight areas at different distances (600-4,000 m) from a dry seasonal forest (Caatinga). We compared the frequency of the main floral visitor (pollinators and robbers) visits and fruit set among areas at the beginning and end of the dry and rainy seasons. Xylocopa species were pollinators, and Apis mellifera, Trigona spinipes and a hummingbird were robbers. Xylocopa visits diminished with increasing distance to native remnants, converse to what was observed for the robbers at the beginning of the dry season. Fruit set was higher at the beginning of the dry season. The distance to the forest affected quality of fruits in terms of length, diameter and skin thickness, which all decreased with increase in remnant distance. Our results show that insect pollination is higher in the dry season, increasing profitability and reducing labour costs for the producer. Considering the influence of distance to native vegetation on pollination, robbery and fruit quality, our study reinforces the necessity for conservation of native vegetation remnants.


Assuntos
Ecossistema , Passiflora/crescimento & desenvolvimento , Brasil , Clima , Geografia , Chuva , Estações do Ano , Temperatura
13.
Plant Biol (Stuttg) ; 20(4): 797-801, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29573080

RESUMO

Monomorphic enantiostylous species produce flowers with a displacement of the style to the left (L) or right (R) on the same individual, and may exhibit different dynamics for the production of these floral types, which may influence levels of selfing. We investigated the production dynamics of L and R floral types in seven species and a variety of monomorphic enantiostylous species of the genera Senna and Chamaecrista. Our hypothesis was that most species present similar proportions of floral morphs each day. Individuals were classified daily over a period of 7 days according to the functional status, i.e. the proportion of floral morphs as functionally L, R or reciprocal (REC, i.e. similar proportions of the two floral morphs), and also according to the number of consecutive days in which they exhibited the same functional status. All species presented low daily flower production. Most species had individuals classified as functionally R, L and REC, and tend to repeat the same functional status over a few days, although they may change functional status during the flowering period. All species exhibited individuals that were classified as functionally reciprocal when both the daily and total number of flowers produced over 7 days was considered. The occurrence of different functional status has not yet been reported in the literature for enantiostylous species. The distinct strategies observed in the dynamics of floral morph production seemed likely to minimise geitonogamy and to favour cross-pollination between individuals (xenogamy).


Assuntos
Fabaceae/fisiologia , Flores/fisiologia , Brasil , Fabaceae/anatomia & histologia , Flores/anatomia & histologia
14.
Indian J Nephrol ; 26(6): 393-397, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27942168

RESUMO

There is a dire need to evaluate new strategies to bridge the wide kidney demand-supply gap. The current study examined the attitude of medical professionals regarding controversial issues pertaining to transplantation. A questionnaire, presenting controversial issues related to kidney transplantation, in an agree-disagree format with supporting reasons, was employed. The research was exploratory. Data were analyzed quantitatively and qualitatively. The sample comprised 140 doctors from Mumbai (mean = 38.1 years, standard deviation = 17.95; Males = 44.3%, Females = 55.7%). Whereas 47.1% of the participants felt that live donors should be given incentives for kidney donation, others (52.9%) disagreed, fearing commercialization and illegal activities. The eligibility of patients with HIV/hepatitis for a transplant was denied by 52.9% because of poor outcomes, with the others (47.1%) maintaining that these individuals too had a right to live. A substantial majority (90.7%) of the participants maintained that organ donors should be given priority in the event of a future need for an organ because their previous humane act should be rewarded (47.1%). Most of the participants (91.4%) felt that individuals from the higher socioeconomic strata should not receive preference for kidney transplantation. A majority (77.1%) of them were also against kidney selling getting legalized. Compulsory possession of a donor card elicited mixed responses, with some accepting (56.4%), but others rejecting (43.6%) this idea as donation was perceived to be a voluntary act (33.6%). While compulsory kidney donation found favor with 44.3%, it found disfavor with others (55.7%). This study will benefit transplant healthcare personnel to formulate new policies in relation to kidney donation/transplantation.

15.
Braz J Med Biol Res ; 49(12): e5519, 2016 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-27982280

RESUMO

The presence of the single nucleotide polymorphisms in exon 1 of the mannose-binding lectin 2 (MBL2) gene was evaluated in a sample of 159 patients undergoing coronary artery bypass surgery (71 patients undergoing valve replacement surgery and 300 control subjects) to investigate a possible association between polymorphisms and heart disease with Chlamydia infection. The identification of the alleles B and D was performed using real time polymerase chain reaction (PCR) and of the allele C was accomplished through PCR assays followed by digestion with the restriction enzyme. The comparative analysis of allelic and genotypic frequencies between the three groups did not reveal any significant difference, even when related to previous Chlamydia infection. Variations in the MBL plasma levels were influenced by the presence of polymorphisms, being significantly higher in the group of cardiac patients, but without representing a risk for the disease. The results showed that despite MBL2 gene polymorphisms being associated with the protein plasma levels, the polymorphisms were not enough to predict the development of heart disease, regardless of infection with both species of Chlamydia.


Assuntos
Infecções por Chlamydia/sangue , Infecções por Chlamydia/genética , Doenças das Valvas Cardíacas/microbiologia , Lectina de Ligação a Manose/sangue , Lectina de Ligação a Manose/genética , Estudos de Casos e Controles , Infecções por Chlamydia/diagnóstico , Estudos Transversais , Feminino , Frequência do Gene , Predisposição Genética para Doença , Genótipo , Doenças das Valvas Cardíacas/sangue , Doenças das Valvas Cardíacas/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Polimorfismo de Nucleotídeo Único
16.
Adv Microb Physiol ; 68: 219-352, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27134025

RESUMO

Electron transport phosphorylation is the central mechanism for most prokaryotic species to harvest energy released in the respiration of their substrates as ATP. Microorganisms have evolved incredible variations on this principle, most of these we perhaps do not know, considering that only a fraction of the microbial richness is known. Besides these variations, microbial species may show substantial versatility in using respiratory systems. In connection herewith, regulatory mechanisms control the expression of these respiratory enzyme systems and their assembly at the translational and posttranslational levels, to optimally accommodate changes in the supply of their energy substrates. Here, we present an overview of methods and techniques from the field of proteomics to explore bacterial electron transfer chains and their regulation at levels ranging from the whole organism down to the Ångstrom scales of protein structures. From the survey of the literature on this subject, it is concluded that proteomics, indeed, has substantially contributed to our comprehending of bacterial respiratory mechanisms, often in elegant combinations with genetic and biochemical approaches. However, we also note that advanced proteomics offers a wealth of opportunities, which have not been exploited at all, or at best underexploited in hypothesis-driving and hypothesis-driven research on bacterial bioenergetics. Examples obtained from the related area of mitochondrial oxidative phosphorylation research, where the application of advanced proteomics is more common, may illustrate these opportunities.


Assuntos
Bactérias/metabolismo , Complexo II de Transporte de Elétrons/ultraestrutura , Complexo I de Transporte de Elétrons/ultraestrutura , Proteômica/métodos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Espectrometria de Massas em Tandem/métodos , Trifosfato de Adenosina/metabolismo , Transporte de Elétrons , Oxirredução , Fosforilação Oxidativa , Estresse Oxidativo/fisiologia , Oxigênio/metabolismo , Fosforilação/fisiologia , Processamento de Proteína Pós-Traducional/fisiologia
17.
Public Health ; 140: 244-249, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27216579

RESUMO

OBJECTIVE: To investigate the association between 5-min Apgar score and socio-economic characteristics of pregnant women, particularly education level. STUDY DESIGN: Population-based cross-sectional study. METHODS: This study used hospital records of live term singleton births in Brazil from 2004 to 2009, obtained from the Ministry of Health National Information System. Crude and adjusted odds ratios (ORs) were used to estimate the risk of a low 5-min Apgar score (≤6) associated with maternal education level, maternal age, marital status, primiparity, number of prenatal visits and mode of delivery (vaginal/caesarean section). RESULTS: Nearly 12 million records were analysed. Births from mothers with 0, 1-3, 4-7 and 8-11 years of education resulted in crude ORs for low 5-min Apgar score of 3.1, 2.2, 1.8 and 1.3, respectively (reference: ≥12 years of education). The crude OR for mothers aged ≥41 years (reference 21-34 years) was 1.4, but no risk was detected for those with ≥12 years of education and those who gave birth by caesarean section (OR 1.0 [95% confidence interval 0.9-1.2]). Generally, the risk of a low 5-min Apgar score was found to increase as maternal age moved away from 21 to 34 years (OR 1.1-1.7), and for mothers with the same characteristics, the risk of a low 5-min Apgar score was found to decrease markedly as education level increased (adjusted OR decreased from 2.6 to 1.2). CONCLUSION: Maternal education level is clearly associated with the risk of a low 5-min Apgar score.


Assuntos
Índice de Apgar , Escolaridade , Mães/estatística & dados numéricos , Adolescente , Adulto , Brasil , Criança , Estudos Transversais , Feminino , Humanos , Recém-Nascido , Pessoa de Meia-Idade , Gravidez , Fatores de Risco , Adulto Jovem
18.
Braz. j. med. biol. res ; 49(12): e5519, 2016. tab, graf
Artigo em Inglês | LILACS | ID: biblio-828177

RESUMO

The presence of the single nucleotide polymorphisms in exon 1 of the mannose-binding lectin 2 (MBL2) gene was evaluated in a sample of 159 patients undergoing coronary artery bypass surgery (71 patients undergoing valve replacement surgery and 300 control subjects) to investigate a possible association between polymorphisms and heart disease with Chlamydia infection. The identification of the alleles B and D was performed using real time polymerase chain reaction (PCR) and of the allele C was accomplished through PCR assays followed by digestion with the restriction enzyme. The comparative analysis of allelic and genotypic frequencies between the three groups did not reveal any significant difference, even when related to previous Chlamydia infection. Variations in the MBL plasma levels were influenced by the presence of polymorphisms, being significantly higher in the group of cardiac patients, but without representing a risk for the disease. The results showed that despite MBL2 gene polymorphisms being associated with the protein plasma levels, the polymorphisms were not enough to predict the development of heart disease, regardless of infection with both species of Chlamydia.


Assuntos
Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Infecções por Chlamydia/sangue , Infecções por Chlamydia/genética , Doenças das Valvas Cardíacas/microbiologia , Lectina de Ligação a Manose/sangue , Lectina de Ligação a Manose/genética , Estudos de Casos e Controles , Infecções por Chlamydia/diagnóstico , Estudos Transversais , Frequência do Gene , Predisposição Genética para Doença , Genótipo , Doenças das Valvas Cardíacas/sangue , Doenças das Valvas Cardíacas/cirurgia , Reação em Cadeia da Polimerase , Polimorfismo de Nucleotídeo Único
19.
Plant Biol (Stuttg) ; 17(3): 740-5, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25363754

RESUMO

Species of the subtribe Cassiinae present a wide diversity of floral types. Until recently it was considered that this diversity did not extend to their reproductive mechanisms. However, studies have recorded some variations in the enantiostylous pattern in this plant group. This study aims to investigate the morphological and functional variations of enantiostyly in species of the subtribe Cassiinae. Additionally, it proposes the recognition of enantiostylous types (ET) based on pollen deposition and capture mode. Morphological data were collected in fresh and fixed (alcohol 70%) buds and flowers, and also using photos and rehydrated material from herbarium sheets, for a total of 59 species. The parameters used to establish the ETs were pollination type, nature of pollen deposition on the pollinator body, deposition type, number of petals involved in pollen deposition, and pollen pathway. Morpho-functional features allowed the recognition of seven enantiostylous types (Flexuosa, Cana, Macranthera, Martiana, Amiciella, Repens and Ramosa) that present several levels of complexity. The type Ramosa was the most common and the Cana type was the least common. The types Repens, Martiana and Flexuosa do not have reciprocal pollen deposition, thus species with these types may be considered atypical. The groups resulting from similarity analysis partially coincide with the clades proposed in phylogenetic studies of Cassiinae. The recognition of functional ETs is important for understanding the evolution of reproductive strategies of Cassiinae species, and indicates an interesting line of investigation of enantiostyly in other plant groups.


Assuntos
Evolução Biológica , Fabaceae/anatomia & histologia , Flores/anatomia & histologia , Fenótipo , Filogenia , Polinização , Fabaceae/genética , Pólen , Reprodução
20.
Environ Sci Technol ; 48(14): 7933-41, 2014 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-24941285

RESUMO

The role played by the natural organic ligands excreted by the green algae Dunaliella tertiolecta on the Fe(II) oxidation rate constants was studied at different stages of growth. The concentration of dissolved organic carbon increased from 2.1 to 7.1 mg L(-1) over time of culture. The oxidation kinetics of Fe(II) was studied at nanomolar levels and under different physicochemical conditions of pH (7.2-8.2), temperature (5-35 °C), salinity (10-37), and dissolved organic carbon produced by cells (2.1-7.1 mg L(-1)). The experimental rate always decreased in the presence of organic exudates with respect to that in the control seawater. The Fe(II) oxidation rate constant was also studied in the context of Marcus theory, where ΔG° was 39.31-51.48 kJ mol(-1). A kinetic modeling approach was applied for computing the equilibrium and rate constants for Fe(II) and exudates present in solution, the Fe(II) speciation, and the contribution of each Fe(II) species to the overall oxidation rate constant. The best fit model took into account two acidity equilibrium constants for the Fe(II) complexing ligands with pKa,1=9.45 and pKa,2=4.9. The Fe(II) complexing constants were KFe(II)-LH=3×10(10) and KFe(II)-L=10(7), and the corresponding computed oxidation rates were 68±2 and 36±8 M(-1) min(-1), respectively.


Assuntos
Clorófitas/metabolismo , Compostos Ferrosos/metabolismo , Ferro/metabolismo , Compostos Orgânicos/metabolismo , Exsudatos de Plantas/metabolismo , Água do Mar/química , Compostos Ferrosos/química , Concentração de Íons de Hidrogênio , Ferro/química , Cinética , Modelos Químicos , Oxirredução , Salinidade , Soluções , Temperatura
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