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31.
32.
Cristiane V. C. Nobre Ana M. M. Gomes Ana P. M. Gomes Antonio A. Gomes Ana P. C. Nascimento 《Gerodontology》2020,37(3):297-302
Objective: To evaluate the efficacy of electric and conventional toothbrushes for a group of elderly individuals. Background: Although the electric toothbrush has been recommended for elderly individuals, there had previously never been a study regarding its efficacy. Material and methods: Sixty independent elders of both genders with different oral conditions from the Center Adult Day Vitória, Espírito Santo, Brazil, were randomly divided into two groups of 30 individuals. One group received the Oral B CrossAction Power electric toothbrush, whereas the other received a conventional Bitufo Class 32 soft toothbrush to perform oral hygiene. The bacterial plaque index (O’Leary Plaque Index) and DMFT index were assessed as a measure of oral hygiene and oral health. The data were analysed using the Shapiro–Wilk, Mann–Whitney and Wilcoxon tests. Results: The results of the efficacy of the Oral B Cross Action Power electric toothbrush demonstrated that on the 7th and 15th days, the bacterial plaque indexes were 24.91 ± 12.81 and 22.11 ± 14.46, respectively, which corresponds to a 50.24% removal of bacterial plaque on the 7th and 55.83% on the 15th days. Although the electric toothbrush removed more bacterial plaque than the conventional toothbrush, the difference was not statistically significant. Conclusion: Both the conventional and the electric toothbrushes were effective in removing bacterial plaque within the elderly group. More studies are necessary to test the efficacy of electric toothbrushes in relation to conventional toothbrushes for elderly patients. 相似文献
33.
Monteiro SP do Brasil PE Cabello GM de Souza RV Brasil P Georg I Cabello PH De Castro L 《Memórias do Instituto Oswaldo Cruz》2012,107(2):224-230
Severe forms of dengue, such as dengue haemorrhagic fever (DHF) and dengue shock syndrome, are examples of a complex pathogenic mechanism in which the virus, environment and host immune response interact. The influence of the host's genetic predisposition to susceptibility or resistance to infectious diseases has been evidenced in several studies. The association of the human leukocyte antigen gene (HLA) class I alleles with DHF susceptibility or resistance has been reported in ethnically and geographically distinct populations. Due to these ethnic and viral strain differences, associations occur in each population, independently with a specific allele, which most likely explains the associations of several alleles with DHF. As the potential role of HLA alleles in the progression of DHF in Brazilian patients remains unknown, we then identified HLA-A alleles in 67 patients with dengue fever and 42 with DHF from Rio de Janeiro, Brazil, selected from 2002-2008 by the sequence-based typing technique. Statistical analysis revealed an association between the HLA-A*01 allele and DHF [odds ratio (OR) = 2.7, p = 0.01], while analysis of the HLA-A*31 allele (OR = 0.5, p = 0.11) suggested a potential protective role in DHF that should be further investigated. This study provides evidence that HLA class I alleles might be important risk factors for DHF in Brazilian patients. 相似文献
34.
Collagen peptides modulate the metabolism of extracellular matrix by human dermal fibroblasts derived from sun‐protected and sun‐exposed body sites 下载免费PDF全文
Vivian Zague Jonatas Bussador do Amaral Paula Rezende Teixeira Evandro Luis de Oliveira Niero Camila Lauand Glaucia Maria Machado‐Santelli 《Cell biology international》2018,42(1):95-104
Clinical data published in recent years have demonstrated positive effects of collagen hydrolysate (CH) on skin aging clinical signs. CH use as food supplement has a long history; however, few studies have addressed the underlying purpose of CH on the cellular and molecular biology of skin cells that could elucidate clinical improvement findings. Wide diversity of characteristics has been reported for dermal fibroblasts derived from different body sites and it is unknown whether collagen peptides could modulate differently cells from chronological aged and photoaged skin areas. This study investigated the influence of CH on the extracellular matrix metabolism and proliferation of human dermal fibroblasts (HDFs) derived from chronological aged (sun‐protected) and photoaged (sun‐exposed) body sites. CH treatment did not affect cellular proliferation of either cell cultures, but notably modulated cell metabolism in monolayer model, increasing the content of dermal matrix precursor and main protein, procollagen I and collagen I, respectively. These effects were confirmed in the human dermal equivalent model. The increase in collagen content in the cultures was attributed to stimulation of biosynthesis and decreased collagen I metabolism through inhibition of metalloproteinase activity (MMP) 1 and 2. Modulation of CH in dermal metabolism did not differ between cells derived from sun‐protected and sun‐exposed areas, although lower concentrations of CH seemed to be enough to stimulate sun‐exposed‐derived HDFs, suggesting more pronounced effect in these cells. This study contributes to understanding the biological effects of CH on skin cells and viability of its use as a functional ingredient in food supplements. 相似文献
35.
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Gesteira AS Micheli F Carels N Da Silva AC Gramacho KP Schuster I Macêdo JN Pereira GA Cascardo JC 《Annals of botany》2007,100(1):129-140
BACKGROUND AND AIMS: Witches' broom disease is caused by the hemibiotrophic basidiomycete Moniliophthora perniciosa, and is one of the most important diseases of cacao in the western hemisphere. Because very little is known about the global process of such disease development, expressed sequence tags (ESTs) were used to identify genes expressed during the Theobroma cacao-Moniliophthora perniciosa interaction. METHODS: Two cDNA libraries corresponding to the resistant (RT) and susceptible (SP) cacao-M. perniciosa interactions were constructed from total RNA, using the DB SMART Creator cDNA library kit (Clontech). Clones were randomly selected, sequenced from the 5' end and analysed using bioinformatics tools including in silico analysis of the differential gene expression. KEY RESULTS: A total of 6884 ESTs were generated from the RT and SP cDNA libraries. These ESTs were composed of 2585 singlets and 341 contigs for a total of 2926 non-redundant sequences. The redundancy of the libraries was low and their specificity high when compared with the few other cacao libraries already published. Sequence analysis allowed the assignment of a putative functional category for 54 % of sequences, whereas approx. 22 % of sequences corresponded to unknown function and approx. 24 % of sequences did not show any significant similarity with other proteins present in the database. Despite the similar overall distribution of the sequences in functional categories between the two libraries, qualitative differences were observed. Genes involved during the defence response to pathogen infection or in programmed cell death were identified, such as pathogenesis related-proteins, trypsin inhibitor or oxalate oxidase, and some of them showed an in silico differential expression between the resistant and the susceptible interactions. CONCLUSIONS: As far as is known this is the first EST resource from the cacao-M. perniciosa interaction and it is believed that it will provide a significant contribution to the understanding of the molecular mechanisms of the resistance and susceptibility of cacao to M. perniciosa, to develop strategies to control witches' broom, and as a source of polymorphism for molecular marker development and marker-assisted selection. 相似文献
37.
Re-examination of the putative roles of insulin and prolactin in the regulation of lipid deposition and lipogenesis in vivo in mammary gland and white and brown adipose tissue of lactating rats and litter-removed rats. 下载免费PDF全文
1. The effects of various treatments to alter either plasma prolactin (bromocryptine administration or removal of litter) or the metabolic activity of the mammary gland (unilateral or complete teat sealing) on the disposal of oral [14C]lipid between 14CO2 production and [14C]lipid accumulation in tissues of lactating rats were studied. In addition, the rates of lipogenesis in vivo were measured in mammary gland, brown and white adipose tissue and liver. 2. Bromocryptine administration lowered plasma prolactin, but did not alter [14C]lipid accumulation in mammary gland or in white and brown adipose tissue. 3. In contrast, complete sealing of teats results in no change in plasma prolactin, but a 90% decrease in [14C]lipid accumulation in mammary gland and a 4-fold increase in white and brown adipose tissue. The rate of lipogenesis in mammary gland was decreased by 95%, but there was no change in the rate in white and brown adipose tissue. Unilateral sealing of teats resulted in a decrease in [14C]lipid accumulation in white adipose tissue. 4. Removal of the litter for 24 h (low prolactin) produced a similar pattern to complete teat sealing, except that there was a 6-fold increase in lipogenesis in white adipose tissue. Re-suckling for 5 h increased plasma prolactin, but did not alter the response seen in litter-removed lactating rats. 5. Changes in lipoprotein lipase activity and in plasma insulin paralleled the reciprocal changes in [14C]lipid accumulation in white and brown adipose tissue and in mammary gland. 6. It is concluded that the plasma insulin is more important than prolactin in regulating lipid deposition in adipose tissue during lactation, and that any effects of prolactin must be indirect. 相似文献
38.
Monteiro-Vitorello CB Camargo LE Van Sluys MA Kitajima JP Truffi D do Amaral AM Harakava R de Oliveira JC Wood D de Oliveira MC Miyaki C Takita MA da Silva AC Furlan LR Carraro DM Camarotte G Almeida NF Carrer H Coutinho LL El-Dorry HA Ferro MI Gagliardi PR Giglioti E Goldman MH Goldman GH Kimura ET Ferro ES Kuramae EE Lemos EG Lemos MV Mauro SM Machado MA Marino CL Menck CF Nunes LR Oliveira RC Pereira GG Siqueira W de Souza AA Tsai SM Zanca AS Simpson AJ Brumbley SM Setúbal JC 《Molecular plant-microbe interactions : MPMI》2004,17(8):827-836
The genome sequence of Leifsonia xyli subsp. xyli, which causes ratoon stunting disease and affects sugarcane worldwide, was determined. The single circular chromosome of Leifsonia xyli subsp. xyli CTCB07 was 2.6 Mb in length with a GC content of 68% and 2,044 predicted open reading frames. The analysis also revealed 307 predicted pseudogenes, which is more than any bacterial plant pathogen sequenced to date. Many of these pseudogenes, if functional, would likely be involved in the degradation of plant heteropolysaccharides, uptake of free sugars, and synthesis of amino acids. Although L. xyli subsp. xyli has only been identified colonizing the xylem vessels of sugarcane, the numbers of predicted regulatory genes and sugar transporters are similar to those in free-living organisms. Some of the predicted pathogenicity genes appear to have been acquired by lateral transfer and include genes for cellulase, pectinase, wilt-inducing protein, lysozyme, and desaturase. The presence of the latter may contribute to stunting, since it is likely involved in the synthesis of abscisic acid, a hormone that arrests growth. Our findings are consistent with the nutritionally fastidious behavior exhibited by L. xyli subsp. xyli and suggest an ongoing adaptation to the restricted ecological niche it inhabits. 相似文献
39.
Edleide L. da Silva Cenira M. de Carvalho Ruth R. do Nascimento Adriana L. Mendonça Carlos E. da Silva Gláucia B. Gonçalves Maria do Rosário T. de Freitas & Antônio E. G. Sant'Ana 《Ethology : formerly Zeitschrift fur Tierpsychologie》2006,112(10):971-976
The Annona fruit borer, Cerconota anonella, causes significant damage to the fruits of Annona squamosa (custard apple) and A. muricata (soursop). The methods currently available for the control of this pest are costly and new techniques, possibly involving the use of pheromones for trapping or disrupting the mating cycle of the insect are required. In order to provide the basic information required for the development of new control systems, the reproductive behaviour of the moth was observed under laboratory conditions. The calling and courtship behaviours exhibited by virgin females and males of C. anonella commenced at the eighth hour of the scotophase and continued for a 3.5‐h period. Males were attracted by conspecific females as young as 1 d old, and showed a courtship behaviour composed of three steps: antennation, wing fanning and short flights. Mating mainly occurred when both males and females were between 2 and 5 d old, but maximum activity was observed on the third day after emergence. Receptive females elevated their wings, showing their abdomens where the abdominal hairpencils were already exposed. As part of the courtship repertoire and immediately prior to copula, males performed pronounced sideways movements of their abdomens, a behaviour that appears to be exclusive to C. anonella. 相似文献
40.
Cristiane Pilisso Patrícia de Oliveira Carvalho Maria da Graa Nascimento 《Process Biochemistry》2009,44(12):1352-1357
The enzymatic acylation of (RS)-phenylethylamine with different acyl donors catalysed by lipases, was studied in organic solvents with different hydrophobicities and in mixtures with ionic liquids ((ILs); [BMIm][BF4], [BMIm][SCN], [BMIm][Cl] and [BMIm][PF6]). Using lipases from Candida antarctica B (CAL-B) and from Aspergillus niger higher conversion degrees and E-values were obtained with ethyl acetate as the acyl donor. When CAL-B was used as the biocatalyst, in a two-phase system formed by [BMIm][X]/dichloromethane or [BMIm][X]/chloroform, the selectivity was better than that obtained in pure organic solvents. The selectivity was found to be related to individual anions in ILs. In this reaction, the ion effectiveness in enhancing the enzyme selectivity followed the series: Cl− > SCN− > BF4− > PF6− in mixtures with dichloromethane, and PF6− > BF4− > SCN− > Cl− in mixtures with chloroform. 相似文献