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131.
Rodolfo Assis Lisboa Felipe Assis Lisboa Guilherme de Castro Santos Marcus Vinícius Melo Andrade José Renan Cunha-Melo 《In vitro cellular & developmental biology. Animal》2009,45(10):614-621
Orthodontic force compresses the periodontal ligament promoting the expression of pro-inflammatory mediators and matrix metalloproteinases
responsible for tooth movement. The extent in time while periodontal cells are being treated and the increment in the amount
of mechanical stress caused by the orthodontic force is thought to regulate the levels of metalloproteinases in the periodontal
tissue. To study the possible regulation in the activity of metalloproteinases 2, 3, 7, 9, and 10 by simulated orthodontic
force, human periodontal ligament fibroblast cultures were centrifuged (141×g) for 30, 60, 90, and 120 min, simulating the orthodontic force. Cell viability, protein quantification, and activity of metalloproteinases
by zymography were evaluated at 24, 48, and 72 h after centrifugation in both cell lysates and growth medium. The activity
of the 72-kDa matrix metalloproteinase 2 was decreased at 24 h regardless of the duration of centrifugation and at 48 h in
cells centrifuged for 30 min only. Decrease in the amount of total protein in lysates was seen at 48 and 72 h with no change
in cell viability. The data seem to indicate that the amount of mechanical stress regulates the levels of secreted matrix
metalloproteinase 2. In addition, the centrifugation as a model for simulated orthodontic force may be used as a simple and
reliable method to study the role played by matrix metalloproteinases in periodontal ligament when submitted to mechanical
force as occurring during tooth movement. 相似文献
132.
Chester Bittencourt Sacramento Vanessa Dionisio Cantagalli Mariana Grings Leonardo Pinto Carvalho José Carlos Costa Baptista‐Silva Abram Beutel Cassia Toledo Bergamaschi Ruy Ribeiro de Campos Junior Jane Zveiter de Moraes Christina Maeda Takiya Vívian Yochiko Samoto Radovan Borojevic Flavia Helena da Silva Nance Beyer Nardi Hans Fernando Dohmann Hamilton Silva Junior Valderez Bastos Valero Sang Won Han 《The journal of gene medicine》2009,11(4):345-353
133.
Bastos HB Gonçalves EC Ferrari SF Silva A Schneider MP 《Genetics and molecular biology》2010,33(4):774-780
We genotyped 15 microsatellite loci in order to evaluate the effects of habitat fragmentation, caused by flooding of the Tucuruí reservoir, on the genetic structure of Alouatta belzebul in eastern Amazonia. The analysis included two populations sampled in 1984, representing both margins of the Tocantins river, and three populations sampled 18 years later. Minimal differences in the diversity levels between present-day (Ho = 0.62-0.69 and A(R) = 6.07-7.21) and pre-flooding (Ho = 0.60-0.62 and A (R) = 6.27-6.77) populations indicated there was no significant loss of genetic variability, possibly because of successful management strategies applied during the flooding. The changes observed were limited to shifts in the composition of alleles, which presumably reflect the admixture of subpopulations during flooding. Given this, there were significant differences in the Rst values (p = 0.05) in all but one between-site comparison. Both present-day and original populations showed a deficit of heterozygotes, which suggests that this may be typical of the species, at least at a local level, perhaps because of specific ecological characteristics. The relatively large number of private alleles recorded in all populations may be a consequence of the Wahlund effect resulting from population admixture or a process of expansion rather than the loss of rare alleles through genetic drift. Additionally, the levels of genetic variability observed in this study were higher than those reported for other species of Neotropical primates, suggesting good fitness levels in these A. belzebul populations. Regular genetic monitoring of remnant populations, especially on islands, should nevertheless be an integral component of long-term management strategies. 相似文献
134.
135.
Luciano Pamplona de Góes Cavalcanti Lia Alves Martins Mota Gustavo Porto Lustosa Mayara Carvalho Fortes Davi Alves Martins Mota Ant?nio Afonso Bezerra Lima Ivo Castelo Branco Coelho Maria Paula Gomes Mour?o 《Memórias do Instituto Oswaldo Cruz》2014,109(1):93-98
In 2009, the World Health Organization (WHO) issued a new guideline that stratifies
dengue-affected patients into severe (SD) and non-severe dengue (NSD) (with or
without warning signs). To evaluate the new recommendations, we completed a
retrospective cross-sectional study of the dengue haemorrhagic fever (DHF) cases
reported during an outbreak in 2011 in northeastern Brazil. We investigated 84
suspected DHF patients, including 45 (53.6%) males and 39 (46.4%) females. The ages
of the patients ranged from five-83 years and the median age was 29. According to the
DHF/dengue shock syndrome classification, 53 (63.1%) patients were classified as
having dengue fever and 31 (36.9%) as having DHF. According to the 2009 WHO
classification, 32 (38.1%) patients were grouped as having NSD [4 (4.8%) without
warning signs and 28 (33.3%) with warning signs] and 52 (61.9%) as having SD. A
better performance of the revised classification in the detection of severe clinical
manifestations allows for an improved detection of patients with SD and may reduce
deaths. The revised classification will not only facilitate effective screening and
patient management, but will also enable the collection of standardised surveillance
data for future epidemiological and clinical studies. 相似文献
136.
Lactoferrin-derived antimicrobial peptide induces a micellar cubic phase in a model membrane system 总被引:1,自引:0,他引:1
Bastos M Silva T Teixeira V Nazmi K Bolscher JG Funari SS Uhríková D 《Biophysical journal》2011,(3):L20-L22
The observation of a micellar cubic phase is reported for a mixture of an antimicrobial peptide from the Lactoferrin family, LFampin 265-284, and a model membrane system of dimyristoylphosphatidylcholine/dimyristoylphosphatidylglycerol (3:1), as derived from small-angle x-ray diffraction (SAXD) measurements. The system shows remarkable thermotropic polymorphism: the peptide disrupts the lipid bilayer, forming a cubic phase of the space group Pm3n (t < 28°C), and as the temperature increases it shows a complex phase behavior (not fully clarified by SAXD). The onset, volume fraction of each phase, and phase parameters are seen to vary with peptide/lipid ratio and temperature. The obtained SAXD data represent the first experimental evidence, to our knowledge, of a micellar cubic phase in the context of antimicrobial peptide/membrane interaction. We propose that the micellization of the membrane according to the carpet model, for long proposed as a possible mechanism of action, can go through the formation of a cubic micellar phase. 相似文献
137.
Tick-borne diseases in horses are caused by the intraerythrocytic protozoan parasites Theileria equi and Babesia caballi. Although T. equi is highly endemic in Latin America, the New World vector of this important parasite is controversial. The aim of this study was to test the ability of nymph Amblyomma cajennense ticks acquire infection by T. equi following feeding on infected horses. Three experiments were performed: tick acquisition of T. equi from an experimentally infected horse, tick acquisition of T. equi from naturally infected foals and tick acquisition of T. equi from a chronically infected horse. A. cajennense adults were dissected and salivary glands were collected in aliquots. Methyl green pyronin staining of the salivary glands did not show the presence of hypertrophy of acini or cell nuclei normally suggestive of Theileria spp. infection. The pools of salivary glands were negative for Theileria DNA in nested PCR assays. Histopathological analysis failed to detect sporoblast and sporozoites of T. equi in salivary gland acini. This study was not able to observe infection of the A. cajennense by T. equi. 相似文献
138.
Miconia manauara has been collected several times in two municipalities in the state of Amazonas, Brazil, and once in nearby Pará. It can
be recognized among species in Miconia sect. Miconia by the leaves with obtuse to rounded bases, entire margins, cuspidate apices and five basal to shortly suprabasal nerves.
The leaves also have glabrous mature adaxial leaf surfaces and the abaxial surface with two indument layers, the first consisting
of moderate to dense, ferruginous, sessile stellate trichomes, 0.1–0.2 mm diam., and the second consisting of a dense, granulose-furfuraceous
layer. The inflorescences are glomerulate, the 5-merous flowers have a caducous calyx, minutely papillose petals, ten stamens
that are ventrally bilobed and with a small dorsal, obtuse tooth, and the ovaries are furfuraceous and usually covered by
unbranched trichomes on their apices. 相似文献
139.
Santos ME das C L E Silva F Gomes KB Fernandes AP Freitas FR Faria MC Mota AP Carvalho MG 《Molecular biology reports》2011,38(5):3361-3366
Peripheral arterial disease (PAD) is an atherosclerotic disturbance characterized by a progressive obstruction of lower limb
arteries. Many risk factors associated with PAD development have being reported in the literature. The present study aimed
to investigate whether mutations in the methylenetetrahydrofolate reductase (MTHFR) or in the cystathionine beta synthase
(CBS) genes are associated with higher levels of homocysteine and the risk of PAD in patients from Brazil. This study analyzed
39 patients with PAD and 32 without PAD in whom risk factors and C677T mutations in the MTHFR gene and both 844ins68 and T833C
mutations in the CBS gene were investigated. Although higher levels of homocysteine could be observed in patients with PAD
compared to controls, no association between the increase of homocysteine and the frequency of C677T, 844ins68, and T833C
mutations could be observed. The results suggest that these mutations do not appear to be related to either homocysteine levels
or the development of the disease. However, hyperhomocysteinemia and smoking are important factors in PAD development. 相似文献
140.
França K Villa RT Bastos VR Almeida AC Massucatti K Fukumaru D Bedin V 《Mycopathologia》2011,172(1):69-72
Subcutaneous chromoblastomycosis is an infection commonly seen in tropical and subtropical climates, usually caused by trauma
with vegetables and often affects the host’s lower limbs. We report a case of auricular chromoblastomycosis in a 67-year-old
man and discuss the rarity of this clinical manifestation of chromoblastomycosis in the medical literature. In the present
case, the etiologic agent was Fonsecaea pedrosoi, the most common agent found in Brazil. 相似文献