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1.
Int J Legal Med ; 138(4): 1533-1557, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38538730

RESUMO

INTRODUCTION: Age Estimation has been considered as a human basic right, carried out through the use of tables for dental age assessment based on the chronology of tooth eruption. As such, the final aim of this investigation is to create tables with applicability to the Portuguese population, for the different scoring systems used and combined different statistical approaches. MATERIALS AND METHODS: For this purpose, dental age assessment was achieved in all four third molars, using different scoring systems, in a total sample of 626 orthopantomograms (324 females, 302 males), aged between 12 and 25 years old, from the database population of Lisbon North University Hospital Center, approved by the Ethic Committee. RESULTS: The values of validation showed excellent results both on precision and on reproducibility. Mostly all methods showed statistically significant differences between the estimated age and the chronological age and, therefore, the presence of estimation errors. Kullman's and Mincer's methods are the ones with best applicability in the Portuguese population, in the lower third molars. The reliability measures (sensitivity, specificity and accuracy) values decrease as age increases. CONCLUSION: A combination of the scoring systems as a protocol for dental age assessment in Portuguese nationality was established. Tables, for all the scoring systems used, were made with applicability in the Portuguese population.


Assuntos
Determinação da Idade pelos Dentes , Dente Serotino , Radiografia Panorâmica , Humanos , Determinação da Idade pelos Dentes/métodos , Feminino , Masculino , Criança , Adolescente , Adulto , Adulto Jovem , Dente Serotino/diagnóstico por imagem , Dente Serotino/crescimento & desenvolvimento , Portugal , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
2.
Caries Res ; 58(5): 469-477, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38574474

RESUMO

INTRODUCTION: Pediatric dentistry should rely on evidence-based clinical decisions supported by high-quality, unbiased systematic reviews (SRs). Therefore, the purpose of this study was to systematically evaluate the methodological quality and risk of bias of SRs focused on non- and micro-invasive treatment for caries lesions in primary and permanent teeth. METHODS: A comprehensive search was conducted in multiple databases, including MEDLINE/PubMed, Scopus, Web of Science, EMBASE, Epistemonikos, and ProQuest, up to March 2023 to identify relevant systematic reviews (SRs) focused on non- and micro-invasive caries treatment. Two independent reviewers extracted data from the included SRs and assessed the methodological quality and risk of bias using the AMSTAR 2 and ROBIS tools, respectively. RESULTS: A total of 39 SRs were included in the analysis. Among these, 27 SRs (69.2%) were assessed as having critically low methodological quality, 11 SRs (28.2%) were considered to have low methodological quality, and only one SR was rated as high-quality. The primary concern identified was the absence of protocol registration before commencing of the study, observed in 33 SR when using the AMSTAR 2 tool. According to the ROBIS tool, 21 studies (53.8%) were categorized as low risk of bias, 10 (25.6%) as high risk, and eight (20.5%) as unclear risk of bias. CONCLUSION: Our analysis revealed that SRs focused on non- and micro-invasive treatment for caries in children and adolescents had critically low methodological quality according to the AMSTAR 2 tool but demonstrated a low risk of bias based on the ROBIS tool. These findings highlight the importance of emphasizing prospective protocol registration, transparent reporting of statistical analyses, and addressing potential bias implications within this topic. By addressing these issues, we can enhance the quality of SRs and ensure that clinical decisions rely on unbiased and trustworthy evidence.


Assuntos
Viés , Cárie Dentária , Dentição Permanente , Revisões Sistemáticas como Assunto , Dente Decíduo , Cárie Dentária/terapia , Humanos , Dente Decíduo/patologia , Odontologia Baseada em Evidências , Criança
3.
Plant Physiol ; 163(4): 1539-57, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24144790

RESUMO

Sugarcane (Saccharum spp.) is currently one of the most efficient crops in the production of first-generation biofuels. However, the bagasse represents an additional abundant lignocellulosic resource that has the potential to increase the ethanol production per plant. To achieve a more efficient conversion of bagasse into ethanol, a better understanding of the main factors affecting biomass recalcitrance is needed. Because several studies have shown a negative effect of lignin on saccharification yield, the characterization of lignin biosynthesis, structure, and deposition in sugarcane is an important goal. Here, we present, to our knowledge, the first systematic study of lignin deposition during sugarcane stem development, using histological, biochemical, and transcriptional data derived from two sugarcane genotypes with contrasting lignin contents. Lignin amount and composition were determined in rind (outer) and pith (inner) tissues throughout stem development. In addition, the phenolic metabolome was analyzed by ultra-high-performance liquid chromatography-mass spectrometry, which allowed the identification of 35 compounds related to the phenylpropanoid pathway and monolignol biosynthesis. Furthermore, the Sugarcane EST Database was extensively surveyed to identify lignin biosynthetic gene homologs, and the expression of all identified genes during stem development was determined by quantitative reverse transcription-polymerase chain reaction. Our data provide, to our knowledge, the first in-depth characterization of lignin biosynthesis in sugarcane and form the baseline for the rational metabolic engineering of sugarcane feedstock for bioenergy purposes.


Assuntos
Regulação da Expressão Gênica de Plantas , Estudos de Associação Genética , Lignina/metabolismo , Saccharum/genética , Saccharum/metabolismo , Teorema de Bayes , Vias Biossintéticas/genética , Perfilação da Expressão Gênica , Genes de Plantas/genética , Genótipo , Lignina/biossíntese , Lignina/química , Fenóis/metabolismo , Caules de Planta/citologia , Caules de Planta/genética , Caules de Planta/crescimento & desenvolvimento , Caules de Planta/metabolismo , Análise de Componente Principal , Solubilidade
4.
Materials (Basel) ; 16(5)2023 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-36902942

RESUMO

It is crucial for clinical needs to develop novel titanium alloys feasible for long-term use as orthopedic and dental prostheses to prevent adverse implications and further expensive procedures. The primary purpose of this research was to investigate the corrosion and tribocorrosion behavior in the phosphate buffered saline (PBS) of two recently developed titanium alloys, Ti-15Zr and Ti-15Zr-5Mo (wt.%) and compare them with the commercially pure titanium grade 4 (CP-Ti G4). Density, XRF, XRD, OM, SEM, and Vickers microhardness analyses were conducted to give details about the phase composition and the mechanical properties. Additionally, electrochemical impedance spectroscopy was used to supplement the corrosion studies, while confocal microscopy and SEM imaging of the wear track were used to evaluate the tribocorrosion mechanisms. As a result, the Ti-15Zr (α + α' phase) and Ti-15Zr-5Mo (α″ + ß phase) samples exhibited advantageous properties compared to CP-Ti G4 in the electrochemical and tribocorrosion tests. Moreover, a better recovery capacity of the passive oxide layer was observed in the studied alloys. These results open new horizons for biomedical applications of Ti-Zr-Mo alloys, such as dental and orthopedical prostheses.

5.
Acta Stomatol Croat ; 57(1): 43-51, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37288157

RESUMO

Objective: The increasing significance of medicolegal evaluation following maxillofacial traumatic events constitutes a complex issue. This clinical research aimed to assess the current etiology of oral and maxillofacial injuries in Portuguese population. Material and methods: An epidemiological clinical observational study was conducted in Centro Hospitalar Lisboa Norte on a sample of 384 subjects diagnosed with oral and maxillofacial trauma, between 2018 and 2020. Data were collected through clinical reports and analyzed using SPSS version 27. Results: Women and men were nearly identical in the number and distribution, with 49.5% females and 50.5% males. In 2020, there was a decrease in the number of traumatic incidents compared to other years. Falls or accidental descents were found to be the most common cause of injury, accounting for 44.3%, followed by assaults accounting for 24.7%. A total of 84 subjects exhibited soft tissue injuries related to periodontal region. The upper central incisors (174) were the most frequently affected teeth with uncomplicated fractures, and the predominant form of treatment was the administration of pain medication. Conclusion: A correlation between falls or accidental descents, female subjects, and advancing age, as well as between assaults, male subjects, and adults, has been established. Falls or accidental descents and assault were the predominant etiologies, and the year 2020 exhibited a decrease in the incidents of traumatic events.

6.
Acta Trop ; 237: 106744, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36375398

RESUMO

The drugs used in the treatment of leishmaniasis show problems concerning side effects and toxicity. As a result, the search for new actives is necessary, and natural products like carvacrol - 5-isopropyl-2-methylphenol, become a relevant alternative. To enable the use of carvacrol as an antileishmanial agent, thermosensitive hydrogels were developed from poloxamer triblock copolymers 407 (P407) and 188 (P188). Carvacrol-free and carvacrol-containing hydrogels were obtained from P407 alone and from the mixture of P407 and P188. The hydrogels were subjected to Differential scanning calorimetry, Small-angle X-ray scattering, Scanning electron microscopy, and Rheology analysis. The activity of hydrogels and carvacrol isolated against promastigotes and intracellular amastigotes of Leishmania amazonensis and their cytotoxicity in mammalian cells was determined. The sol-gel transition temperature for the binary hydrogel containing carvacrol (HG407/188CA) was 37.04 ± 1.35 °C. HG407/188CA presented lamellar structure at temperatures of 25 °C and 37 °C. HG407/188CA and carvacrol presented IC50 against Leishmania amazonensis promastigotes of 18.68 ± 1.43 µg/mL and 23.83 ± 3.32 µg/mL, respectively, and IC50 against Leishmania amazonensis amastigotes of 35.08 ± 0.75 µg/mL and 29.32 ± 0.21 µg/mL, respectively. HG407/188CA reduced the toxicity of carvacrol in all mammalian cells evaluated, raising the CC50 in murine peritoneal macrophages from 40.23 ± 0.21 µg/mL to 332.6 ± 4.89 µg/mL, obtaining a Selectivity Index (SI) of 9.5 against 1.37 of the isolated carvacrol. HG407/188CA provided higher selectivity of carvacrol for the parasite. Thus, the binary hydrogel obtained may enable the use of carvacrol as a potential antileishmanial agent.


Assuntos
Antiprotozoários , Leishmania mexicana , Camundongos , Animais , Poloxâmero/farmacologia , Camundongos Endogâmicos BALB C , Antiprotozoários/farmacologia , Antiprotozoários/uso terapêutico , Hidrogéis , Mamíferos
7.
Biochim Biophys Acta ; 1798(3): 433-41, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20004174

RESUMO

Anticancer systemic gene silencing therapy has been so far limited by the inexistence of adequate carrier systems that ultimately provide an efficient intracellular delivery into target tumor cells. In this respect, one promising strategy involves the covalent attachment of internalizing-targeting ligands at the extremity of PEG chains grafted onto liposomes. Therefore, the present work aims at designing targeted liposomes containing nucleic acids, with small size, high encapsulation efficiency and able to be actively internalized by SCLC cells, using a hexapeptide (antagonist G) as a targeting ligand. For this purpose, the effect of the liposomal preparation method, loading material (ODN versus siRNA) and peptide-coupling procedure (direct coupling versus post-insertion) on each of the above-mentioned parameters was assessed. Post-insertion of DSPE-PEG-antagonist G conjugates into preformed liposomes herein named as stabilized lipid particles, resulted in targeted vesicles with a mean size of about 130 nm, encapsulation efficiency close to 100%, and a loading capacity of approximately 5 nmol siRNA/mumol of total lipid. In addition, the developed targeted vesicles showed increased internalization in SCLC cells, as well as in other tumor cells and HMEC-1 microvascular endothelial cells. The improved cellular association, however, did not correlate with enhanced downregulation of the target protein (Bcl-2) in SCLC cells. These results indicate that additional improvements need to be performed in the future, namely by ameliorating the access of the nucleic acids to the cytoplasm of the tumor cells following receptor-mediated endocytosis.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Lipossomos/síntese química , Ácidos Nucleicos/metabolismo , Peptídeos/farmacologia , Linhagem Celular Tumoral , Endocitose/efeitos dos fármacos , Fluorometria , Humanos , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , RNA Interferente Pequeno/metabolismo , Transfecção
8.
Rev Med Chil ; 139(12): 1601-4, 2011 Dec.
Artigo em Espanhol | MEDLINE | ID: mdl-22446708

RESUMO

Hypohidrotic ectodermal dysplasia (HED) is a very rare disease characterized by the absence of eccrine glands, dry skin, scanty hair, and dental abnormalities. It is caused by mutations within the ED1 gene, which encodes a protein, ectodysplasin-A (EDA). Clinical characteristic are frontal bossing, saddle nose, pointed chin, a prominent supraorbital ridge with periorbital hyperpigmenta-tion, and anodontia. Those affected show great intolerance to heat. We report the first Mexican 2-year-old boy with an Ala349Thr missense mutation from Tamaulipas, México.


Assuntos
Displasia Ectodérmica Anidrótica Tipo 1/genética , Ectodisplasinas/genética , Mutação de Sentido Incorreto/genética , Pré-Escolar , Displasia Ectodérmica Anidrótica Tipo 1/patologia , Humanos , Masculino
9.
Arch Oral Biol ; 125: 105089, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33640556

RESUMO

OBJECTIVES: The aim of this study is to estimate the cut-off points for the Portuguese legal ages through the I3M, and to compare them with the methods of Demirjian, Nolla and Moorrees. DESIGN: The lower third molars were analyzed on 348 orthopantomography's aged between 12 and 23 years in a Portuguese Population. The images were analyzed by ImageJ and the cut-off points were calculated for the respective legal ages of 14, 16, 18 and 21 years old. RESULTS: The correlation between age and the I3M was 0.862, whereas with Demirjian's stadiums, Nolla's stages, and Moorrees' stages the correlation coefficients were 0.863, 0.842 and 0.844, respectively. For the cut-off point of 0.08 for the age of 18, a sensitivity of 78.99 %, specificity of 93.48 %, an accuracy of 88.54 %, a positive predictive value of 86.24 % and a posteriori Bayes probability of 92.82 %. The cut-off points established for the ages of 14, 16, 18 and 21 years for the Portuguese population achieved an accuracy of 83.67 %, 85.67 %, 88.54 % and 87.11 %, respectively. CONCLUSION: Demirjian's method and Cameriere's method attain quite similar results. In certain ages, the methods of Nolla and Moorrees show higher sensitivity or higher specificity when compared to Cameriere's method, however this last method is more stable in terms of reliability and more suitable to use in the Portuguese population.


Assuntos
Determinação da Idade pelos Dentes , Adolescente , Adulto , Teorema de Bayes , Criança , Humanos , Dente Serotino/diagnóstico por imagem , Portugal , Radiografia Panorâmica , Reprodutibilidade dos Testes , Adulto Jovem
10.
Int J Clin Pediatr Dent ; 12(4): 293-296, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31866713

RESUMO

AIM: To evaluate the association between dental caries and nutritional status in a group of Brazilian schoolchildren, from Manaus. The studied population consisted of 197 students (10-12-year-olds) from public schools at Manaus, Amazonas, Brazil. MATERIALS AND METHODS: A clinical examination was carried out and the decay-missing-filled-teeth index for primary and permanent teeth (dmft and DMFT) was used to evaluate dental caries. Body mass index Z-score was calculated using variables such as individual height, weight, age, and gender. The nutritional status was classified as underweight, eutrophic, overweight, and obese. One-way ANOVA and Tukey's posttests were used for means' comparison between groups. The established alpha was 5%. RESULTS: Eighty-one (41.1%) children were caries-free. Five (2.5%) children were underweight; 127 (64.5%) were eutrophic; 49 (24.9%) were overweight; and 16 (8.1%) were obese. The mean dmft/DMFT index was 1.67 (2.05). Obese children had more caries experience than eutrophic and overweight children (p < 0.05). CONCLUSION: Our study demonstrated that dental caries is associated with obesity in school children from Manaus. HOW TO CITE THIS ARTICLE: Vasconcelos K, Evangelista S, et al. Assessing the Association between Dental Caries and Nutritional Status in Children from the Brazilian State of Amazonas. Int J Clin Pediatr Dent 2019;12(4):293-296.

11.
R Soc Open Sci ; 5(9): 180432, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30839761

RESUMO

This work provides robust oral pathology and stable isotope evidence on Bayesian mixing model for an unexpectedly high consumption of carbohydrates by a Middle Holocene coastal population of the Atlantic Forest of South America, an area traditionally viewed as peripheral to early centres of food production on the continent. A diversified economy with substantial consumption of plant resources was in place at the shellmound (or sambaqui) of Morro do Ouro, in Babitonga Bay, and supported a dense population at ca 4500 cal BP. This dietary composition is unique when compared with that of other contemporary and later groups in the region, including peoples who used ceramics and domesticated crops. The results corroborate independent dietary evidence, such as stone tool artefacts for plant processing and plant microremains in dental calculus of the same individuals, and suggest plant cultivation possibly took place in this region at the same time as the development of early agriculture in Amazonia and the La Plata Basin. Our study situates the Atlantic Forest coast of Brazil on the map of early plant management in the Neotropics.

12.
J Endod ; 44(1): 145-148, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29033083

RESUMO

INTRODUCTION: The aim of this study was to evaluate, under scanning electronic microscopy, the morphological aspect of apical foramen after root canal instrumentation with rotary and reciprocating kinematics at 2 different working length determinations. METHODOLOGY: Sixty mesiobuccal roots of mandibular and maxillary molars presenting with curvature ranging from 30 to 65° were used in this study. The roots were initially scanned with a scanning electronic microscope under ×50 magnification. Roots were divided into 2 different groups (n = 30): group 1 instrumented with rotary kinematics, and group 2 instrumented with reciprocating kinematics. Both groups were instrumented at 2 different working lengths: at the apex and 1 mm beyond the apex. The roots were scanned after the instrumentation at the apex and again after further instrumentation 1 mm beyond the apex. The photomicrographs obtained were assigned to 3 independent evaluators for foraminal deformation assessment through comparison with baseline images. Evaluators were masked with regard to the kinematics and working length used. The Pearson correlation test and Kruskal-Wallis test (method of Dunn) were used for statistical analysis (P < .05). RESULTS: The Pearson Correlation test showed good agreement among evaluators. Foraminal deformation was observed in instrumentation at the apex and 1 mm beyond the apex with both kinematics (P < .05). CONCLUSIONS: Within the limitations of this study, it can be concluded that root canal instrumentation at the apex or 1 mm beyond the apex promoted deformation of the major foramen, regardless of the kinematics.


Assuntos
Preparo de Canal Radicular/métodos , Ápice Dentário/ultraestrutura , Fenômenos Biomecânicos , Humanos , Microscopia Eletrônica de Varredura , Preparo de Canal Radicular/instrumentação
13.
Arch Oral Biol ; 92: 1-7, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29727722

RESUMO

OBJECTIVE: This replication study aimed to evaluate an association between caries experience and polymorphisms in DEFB1 and miRNA202 in two different Brazilian groups. DESIGN: The population consisted in 312 Brazilian children. Genomic DNA for was extracted from buccal cells isolated from saliva. The genotyping analysis of the polymorphisms in DEFB1 and miRNA202 was performed by real-time polymerase chain reactions. The associations between caries experience, genotype and allele distribution was performed, with an alpha of 0.05. RESULTS: A statistical significant difference was observed between allele distribution and the polymorphism rs12355840 in the miRNA202 for permanent dentition in the Manaus group, in which individuals that carry the allele C had almost three times more chance to have caries (p = .021; OR = 2.7, 95% CI = 1.1-6.7). In the Ribeirão Preto group there was a statistical significant difference for the polymorphism rs11362 in the DEFB1 for both dentition in alleles (p = .043) and genotype (p = .020) distributions. The T allele increased in two times the chance to have caries (OR = 2.03; 95% CI = 1.05-4.07). CONCLUSION: In conclusion, the allelic distribution of the polymorphism rs12355840 in miRNA202 was associated with caries experience in the Manaus group. In the Ribeirão Preto group, the allelic and genotypic distributions in the polymorphism rs11362 in DEFB1 were associated with caries experience.


Assuntos
Cárie Dentária/genética , MicroRNAs/genética , Polimorfismo de Nucleotídeo Único , beta-Defensinas/genética , Alelos , Brasil , Criança , Feminino , Genótipo , Humanos , Masculino , Reação em Cadeia da Polimerase em Tempo Real
14.
Insect Biochem Mol Biol ; 37(7): 702-12, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17550826

RESUMO

Triatoma brasiliensis is the most important autochthon vector of Trypanosoma cruzi in Brazil, where it is widely distributed in the semiarid areas of the Northeast. In order to advance the knowledge of the salivary biomolecules of Triatominae, a salivary gland cDNA library of T. brasiliensis was mass sequenced and analyzed. Polypeptides were sequenced by HPLC/Edman degradation experiments. Then 1712 cDNA sequences were obtained and grouped in 786 clusters. The housekeeping category had 24.4% and 17.8% of the clusters and sequences, respectively. The putatively secreted category contained 47.1% of the clusters and 68.2% of the sequences. Finally, 28.5% of the clusters, containing 14% of all sequences, were classified as unknown. The sialoma of T. brasiliensis showed a high amount and great variety of different lipocalins (93.8% of secreted proteins). Remarkably, a great number of serine proteases that were not observed in previous blood-sucking sialotranscriptomes were found. Nine Kazal peptides were identified, among them one with high homology to the tabanid vasodilator vasotab, suggesting that the Triatoma vasodilator could be a Kazal protein.


Assuntos
Biologia Computacional , Biblioteca Gênica , Proteínas de Insetos/genética , Saliva/química , Glândulas Salivares/química , Triatoma/metabolismo , Sequência de Aminoácidos , Animais , Apirase/química , Sangue , Brasil , Clonagem Molecular , Ingestão de Alimentos , Hemeproteínas , Proteínas de Insetos/química , Proteínas de Insetos/metabolismo , Insetos Vetores , Filogenia , Glândulas Salivares/fisiologia , Proteínas e Peptídeos Salivares , Alinhamento de Sequência , Análise de Sequência de DNA , Serina Endopeptidases/isolamento & purificação , Serina Endopeptidases/metabolismo , Triatoma/classificação , Triatoma/genética , Trypanosoma cruzi/fisiologia
15.
Int J Biol Macromol ; 93(Pt A): 1217-1225, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27693339

RESUMO

Bio-composites films were prepared by casting and drying of aqueous solutions containing different weight ratios of chitosan and bark of Mimosa tenuiflora. The physico-chemical and functional properties of the films were characterized by scanning electron microscopy, dynamical mechanical analysis, wettability, cytotoxicity and in vitro antibacterial activities. The morphology studies confirmed that the presence of Mimosa tenuiflora change the surface of films. Moreover, the incorporation of Mimosa tenuiflora improved the thermal stability of the films, as it was indicated by the changes in the glass temperatures obtained. Water-uptake ability changed in relation to polymeric composition of film. This property increased by the addition of Mimosa tenuiflora to the film. Improved antibacterial properties were measured against Escherichia Coli and Micrococcus lysodeikticus or luteus. Finally, cytotoxicity was studied by MTT assay and the films were non-toxic. These preliminary results provide a cheap way to prepare chitosan/Mimosa tenuiflora films for wound healing and skin regeneration.


Assuntos
Quitosana/química , Quitosana/farmacologia , Mimosa/química , Regeneração/efeitos dos fármacos , Pele/efeitos dos fármacos , Adesivo Transdérmico , Células 3T3 , Animais , Antibacterianos/administração & dosagem , Antibacterianos/química , Antibacterianos/farmacologia , Antibacterianos/toxicidade , Bandagens , Materiais Biocompatíveis/administração & dosagem , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Materiais Biocompatíveis/toxicidade , Quitosana/administração & dosagem , Quitosana/toxicidade , Escherichia coli/efeitos dos fármacos , Camundongos , Micrococcus/efeitos dos fármacos , Molhabilidade
16.
J Agric Food Chem ; 63(19): 4708-20, 2015 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-25936563

RESUMO

The lignin deposition in the stem of two sugarcane genotypes was assessed on exposure to water stress. The lignin content and the morphoanatomical characterization of the stem indicated that IACSP94-2094 plants are more lignified than those of IACSP95-5000 genotype, under normal water supply conditions, which was especially associated with higher lignin contents in the rind of mature internodes. Water deficit had negative impact on the biomass production, mostly with IACSP94-2094 plants, possibly due to stress severity or higher susceptibility of that genotype during the stem-lengthening phase. Water deficit led to significant alterations in the expression levels of lignin biosynthesis genes and led to an approximate 60% increase of lignin content in the rind of young internodes in both genotypes. It is concluded that the young rind region was more directly affected by water stress and, depending on the genotype, a higher lignin accumulation may occur in the stem, thus implying lower quality biomass for bioethanol production.


Assuntos
Regulação da Expressão Gênica de Plantas , Lignina/química , Proteínas de Plantas/genética , Saccharum/metabolismo , Água/metabolismo , Genótipo , Lignina/metabolismo , Proteínas de Plantas/metabolismo , Caules de Planta/química , Caules de Planta/metabolismo , Saccharum/química , Saccharum/genética
17.
PLoS One ; 10(8): e0134909, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26241317

RESUMO

Sugarcane is an important crop worldwide for sugar and first generation ethanol production. Recently, the residue of sugarcane mills, named bagasse, has been considered a promising lignocellulosic biomass to produce the second-generation ethanol. Lignin is a major factor limiting the use of bagasse and other plant lignocellulosic materials to produce second-generation ethanol. Lignin biosynthesis pathway is a complex network and changes in the expression of genes of this pathway have in general led to diverse and undesirable impacts on plant structure and physiology. Despite its economic importance, sugarcane genome was still not sequenced. In this study a high-throughput transcriptome evaluation of two sugarcane genotypes contrasting for lignin content was carried out. We generated a set of 85,151 transcripts of sugarcane using RNA-seq and de novo assembling. More than 2,000 transcripts showed differential expression between the genotypes, including several genes involved in the lignin biosynthetic pathway. This information can give valuable knowledge on the lignin biosynthesis and its interactions with other metabolic pathways in the complex sugarcane genome.


Assuntos
Lignina/análise , RNA de Plantas/genética , Saccharum/genética , Transcriptoma , Sequência de Aminoácidos , Sequência de Bases , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Biblioteca Gênica , Genes de Plantas , Genótipo , Sequenciamento de Nucleotídeos em Larga Escala , Lignina/biossíntese , Dados de Sequência Molecular , Filogenia , Proteínas de Plantas/genética , Caules de Planta/metabolismo , RNA de Plantas/biossíntese , RNA de Plantas/isolamento & purificação , Saccharum/química , Homologia de Sequência
18.
Int J Pharm ; 434(1-2): 9-19, 2012 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-22617794

RESUMO

The present work aimed at designing a lipid-based nanocarrier for siRNA delivery toward two cell sub-populations within breast tumors, the cancer and the endothelial cells from angiogenic tumor blood vessels. To achieve such goal, the F3 peptide, which is specifically internalized by nucleolin overexpressed on both those sub-populations, was used as a targeting moiety. The developed F3-targeted stable nucleic acid lipid particles presented adequate features for systemic administration. In addition, the attachment of the F3 peptide onto the liposomal surface enabled an internalization by both cancer and endothelial cells from angiogenic blood vessels that was significantly higher than the one observed with non-cancer cells. Sequence-specific downregulation of enhanced green fluorescent protein (eGFP) in eGFP-overexpressing human cancer cell lines, both at the protein and mRNA levels, was further observed upon delivery of anti-eGFP siRNA by F3-targeted liposomes, in contrast with the non-targeted counterpart. This effect was highly dependent on the content of poly(ethylene glycol) (PEG), as evidenced by the co-localization studies between the siRNA and the lysosomes. Overall, the present work represents an important contribution toward a nanoparticle with multi-targeting capabilities in breast cancer, both at the cellular and molecular level.


Assuntos
Neoplasias da Mama/terapia , Proteínas de Fluorescência Verde/genética , Peptídeos/metabolismo , RNA Interferente Pequeno/administração & dosagem , Neoplasias da Mama/irrigação sanguínea , Neoplasias da Mama/genética , Linhagem Celular , Linhagem Celular Tumoral , Regulação para Baixo , Células Endoteliais/metabolismo , Feminino , Humanos , Lipossomos , Lisossomos/metabolismo , Nanopartículas , Neovascularização Patológica/patologia , Neovascularização Patológica/terapia , Fosfoproteínas/metabolismo , Polietilenoglicóis/química , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/metabolismo , Microambiente Tumoral , Nucleolina
19.
PLoS One ; 6(11): e28088, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22132218

RESUMO

This study performed barcoded multiplex pyrosequencing with a 454 FLX instrument to compare the microbiota of dental root canal infections associated with acute (symptomatic) or chronic (asymptomatic) apical periodontitis. Analysis of samples from 9 acute abscesses and 8 chronic infections yielded partial 16S rRNA gene sequences that were taxonomically classified into 916 bacterial species-level operational taxonomic units (OTUs) (at 3% divergence) belonging to 67 genera and 13 phyla. The most abundant phyla in acute infections were Firmicutes (52%), Fusobacteria (17%) and Bacteroidetes (13%), while in chronic infections the dominant were Firmicutes (59%), Bacteroidetes (14%) and Actinobacteria (10%). Members of Fusobacteria were much more prevalent in acute (89%) than in chronic cases (50%). The most abundant/prevalent genera in acute infections were Fusobacterium and Parvimonas. Twenty genera were exclusively detected in acute infections and 18 in chronic infections. Only 18% (n = 165) of the OTUs at 3% divergence were shared by acute and chronic infections. Diversity and richness estimators revealed that acute infections were significantly more diverse than chronic infections. Although a high interindividual variation in bacterial communities was observed, many samples tended to group together according to the type of infection (acute or chronic). This study is one of the most comprehensive in-deep comparisons of the microbiota associated with acute and chronic dental root canal infections and highlights the role of diverse polymicrobial communities as the unit of pathogenicity in acute infections. The overall diversity of endodontic infections as revealed by the pyrosequencing technique was much higher than previously reported for endodontic infections.


Assuntos
Bactérias/crescimento & desenvolvimento , Infecções Bacterianas/microbiologia , Biodiversidade , Cavidade Pulpar/microbiologia , Cavidade Pulpar/patologia , Doença Aguda , Adolescente , Adulto , Bactérias/genética , Doença Crônica , Análise por Conglomerados , Humanos , Pessoa de Meia-Idade , Filogenia , Análise de Componente Principal , Análise de Sequência de DNA , Adulto Jovem
20.
Rev. bras. neurol ; 52(3): 37-44, jul.-set. 2016. graf, ilus
Artigo em Português | LILACS | ID: biblio-2640

RESUMO

FUNDAMENTO: A paralisia cerebral (PC) é caracterizada por distúrbios do movimento e da postura, que podem estar associados a déficits cognitivos. Tais comprometimentos são atribuídos a lesões não progressivas ao encéfalo em desenvolvimento. No âmbito experimental, modelos animais dessa condição clínica capazes de reproduzir o fenótipo e as alterações estruturais vistas em humanos são escassos. OBJETICO: Investigar as repercussões da indução de um modelo de PC sobre a função cognitiva e estrutura do hipocampo e amígdala em ratos Wistar. MÉTODOS: Dois grupos experimentais foram utilizados: 1) Controle - filhotes de ratas injetadas com solução salina durante a gestação (n=8) e 2) Paralisia cerebral - filhotes de ratas injetadas com Lipopolissacarídeo (LPS) durante a gestação (n=8), submetidos à anóxia perinatal e restrição sensório-motora durante 30 dias. A memória espacial dos animais foi avaliada pela tarefa de reconhecimento da localização de objetos, enquanto o comportamento do tipo ansioso foi verificado pelo teste de labirinto em cruz elevado. Após a avaliação comportamental, os animais foram eutanasiados e os encéfalos dissecados para posterior processamento histológico. RESULTADOS: O grupo PC apresentou déficits de memória espacial e uma redução do número de neurônios granulares no giro denteado. Entretanto o comportamento do tipo ansioso e a histologia do núcleo central e complexo basolateral da amígdala foram semelhantes entre os grupos. CONCLUSÃO: Como observado em parte dos pacientes com PC, este modelo experimental prejudica a memória dependente do hipocampo. Entretanto, a combinação de intervenções não alterou a ansiedade e estrutura da amígdala.


BASIS: Cerebral palsy (CP) is a disorder of movement and posture, which may be associated with cognitive impairments. Such clinical condition is caused by non progressive injuries ocurred during the brain development. In the experimental context, animal models of this condition that can reproduce the phenotype and the structural changes seen in humans are scarce. OBJECTIVE: The present study investigated cognitive function and hippocampus and amygdala structure in rats submitted to a CP model. METHODS: Two experimental groups were used: 1) Control - offspring of rats injected with saline during pregnancy (n = 8) and 2) Cerebral Palsy - offspring of rats injected with lipopolysaccharide (LPS) during pregnancy (n = 8), submitted to perinatal anoxia and sensorimotor restriction for 30 days. The spatial memory was evaluated by the object-placement recog- nition task and anxiety like-behavior by elevated plus maze test. After the behavioral assessment, animals were euthanized and brains dissected for histological processing. RESULTS: The PC group showed spatial memory deficits and a reduction of granule neurons in the dentate gyrus. However, the anxiety like-behavior and the number of neurons in central nucleus and basolateral complex of the amygdala were similar between studied groups. CONCLUSION: This animal model affects the hippocampus dependent memory, a deficit seen in part of CP patients. However, the interventions used did not alter the anxiety like-behavior and amygdala structure.


Assuntos
Animais , Ratos , Paralisia Cerebral/complicações , Paralisia Cerebral/diagnóstico , Transtornos Cognitivos/etiologia , Experimentação Animal , Hipocampo/anatomia & histologia , Tonsila do Cerebelo/anatomia & histologia , Ansiedade , Paralisia Cerebral/induzido quimicamente , Ratos Wistar , Aprendizagem em Labirinto , Memória Espacial , Animais Recém-Nascidos , Corpos de Nissl
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