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91.
Larissa Medeiros de Oliveira Robert Saraiva Matos tefan lu Ana Luisa Farias Rocha Ronald Zico de Aguiar Nunes Jaqueline de Araújo Bezerra Pedro Henrique Campelo Felix Natlia Mayumi Inada Edgar Aparecido Sanches Henrique Duarte da Fonseca Filho 《Materials》2022,15(7)
Biodegradable particles were developed using poly-ε-caprolactone and gelatin carriers containing different concentrations of Allium sativum essential oil (EO) (360 µg/mL, 420 µg/mL, and 460 µg/mL). Atomic force microscopy was useful to evaluate the particles’ surface based on morphological parameters. The particles’ size varied from 150 nm to 300 nm. The diameter was related to the increase of the particles’ height as a function of the EO concentration, influencing the roughness of the surface core values (from 20 to 30 nm) and surface irregularity. The spatial parameters Str (texture aspect ratio) and Std (texture direction) revealed low spatial frequency components. The hybrid parameters Sdq (root mean square gradient) and Sdr (interfacial area ratio) also increased as a function of the EO concentration, revealing fewer flat particles. On the other hand, the functional parameters (inverse areal material ratio and peak extreme height) suggested differences in surface irregularities. Higher concentrations of EO resulted in greater microtexture asperity on the particles’ surface, as well as sharper peaks. The nanoscale morphological surface analysis allowed the determination of the most appropriate concentration of encapsulated EO, influencing statistical surface parameters. 相似文献
92.
Caroline Xavier-Carvalho Renata Duarte da Silva Cezar Naishe Matos Freire Carla Maria Mola de Vasconcelos Victor Edgar Fiestas Solorzano Thiago Gomes de Toledo-Pinto Luciana Gomes Fialho Rodrigo Feliciano do Carmo Luydson Richardson Silva Vasconcelos Marli Tenório Cordeiro Paulo Baptista Elzinandes leal de Azeredo Rivaldo Venâncio da Cunha Luiz José de Souza Antonio Guilherme Pacheco Claire Fernandes Kubelka Patrícia Muniz Mendes Freire de Moura Milton Ozorio Moraes 《Human immunology》2017,78(10):649-656
Outbreaks of the Zika, dengue, and chikungunya viruses, especially in the Americas, pose a global threat due to their rapid spread and difficulty controlling the vector. Extreme phenotypes are often observed, from asymptomatic to severe clinical manifestations, which are well-studied in dengue. Host variations are also important contributors to disease outcomes, and many case-control studies have associated single nucleotide polymorphisms (SNPs) with severe dengue. Here, we found that the TC genotype and T-carriers for SNP rs1285933 in the C-type lectin superfamily member 5 (CLEC5A) gene was associated with severe dengue in a Northern Brazilian population (OR = 2.75 and p-value = 0.01, OR = 2.11 and p-value = 0.04, respectively). We also tested the functional effect of the CLEC5A protein and found that it is upregulated on the surface of human monocytes after in vitro dengue infection. CLEC5A was correlated with viral load inside the monocytes (Spearman r = 0.55, p = 0.008) and TNF production in culture supernatants (Spearman r = 0.72, p = 0.03). Analysis of mRNA in blood samples from DENV4-infected patients exhibiting mild symptoms showed that CLEC5A mRNA expression is correlated with TNF (r = 0.67, p = 0.0001) and other immune mediators. Monocytes from rs1285933 TT/TC individuals showed lower CLEC5A expression compared to CC genotypes. However, in these cells, CLEC5A was not correlated with TNF production. In summary, we confirmed that CLEC5A is genetically associated with dengue severity outcome, playing a central role during the immune response triggered by a dengue viral infection, and rs1285933 is a relevant SNP that is able to regulate signaling pathways after interactions between the dengue virus and CLEC5A receptors. 相似文献
93.
Effect of Disinfection on the Bond Strength between Denture Teeth and Microwave‐Cured Acrylic Resin Denture Base 下载免费PDF全文
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目的探讨经关节入路微创钢板固定(MIPPO)技术治疗股骨远端C型骨折的临床疗效。方法2002年4月~2005年2月,应用MIPPO技术治疗股骨远端C型骨折14例,按AO/ASIF分类:C1型3例,C2型6例,C3型5例。先行关节内骨折切开复位、松质骨螺钉固定,再行髁上部分骨折间接复位、经关节内切口插入髁支撑钢板或LISS钢板桥接固定骨折。结果12例患者获得10~32个月(平均18.4个月)随访,骨折均获愈合,愈合时间10周~12个月,平均4.6个月。按Kolmert和Wulff的评价标准:优4例,良5例,可2例,差1例,优良率为75%。结论应用MIPPO技术治疗股骨远端C型骨折实现了微创操作,具有创伤小、软组织干扰少、骨折愈合快等优点,疗效满意。 相似文献
97.
Identification of the Molecular Determinants of the Antibacterial Activity of LmutTX,a Lys49 Phospholipase A2 Homologue Isolated from Lachesis muta muta Snake Venom (Linnaeus, 1766) 下载免费PDF全文
Rafaela Diniz‐Sousa Cleópatra A. S. Caldeira Anderson M. Kayano Mauro V. Paloschi Daniel. C. Pimenta Rodrigo Simões‐Silva Amália S. Ferreira Fernando B. Zanchi Najla B. Matos Fernando P. Grabner Leonardo A. Calderon Juliana P. Zuliani Andreimar M. Soares 《Basic & clinical pharmacology & toxicology》2018,122(4):413-423
Snake venom phospholipases A2 (PLA2s) are responsible for numerous pathophysiological effects in snakebites; however, their biochemical properties favour antimicrobial actions against different pathogens, thus constituting a true source of potential microbicidal agents. This study describes the isolation of a Lys49 PLA2 homologue from Lachesis muta muta venom using two chromatographic steps: size exclusion and reverse phase. The protein showed a molecular mass of 13,889 Da and was devoid of phospholipase activity on an artificial substrate. The primary structure made it possible to identify an unpublished protein from L. m. muta venom, named LmutTX, that presented high identity with other Lys49 PLA2s from bothropic venoms. Synthetic peptides designed from LmutTX were evaluated for their cytotoxic and antimicrobial activities. LmutTX was cytotoxic against C2C12 myotubes at concentrations of at least 200 μg/mL, whereas the peptides showed a low cytolytic effect. LmutTX showed antibacterial activity against Gram‐positive and Gram‐negative bacteria; however, S. aureusATCC 29213 and MRSA strains were more sensitive to the toxin's action. Synthetic peptides were tested on S. aureus, MRSA and P. aeruginosaATCC 27853 strains, showing promising results. This study describes for the first time the isolation of a Lys49 PLA2 from Lachesis snake venom and shows that peptides from specific regions of the sequence may constitute new sources of molecules with biotechnological potential. 相似文献
98.
Ferreira M Matos RC Oliveira H Nunes B Pereira Mde L 《Human & experimental toxicology》2012,31(3):290-302
In order to assess the effect of arsenic on the male reproductive impairment in mice, 7-week-old animals were exposed to 7.5 mg sodium arsenite (NaAsO(2))/kg body weight, during 35 days (one spermatogenic cycle). One group of animals was sacrificed after exposure, while another group received distilled water for an additional period of 35 days, in order to study the spermatoxic effect and the recovery of spermatogenesis. In mice sacrificed after NaAsO(2) exposure, a decrease in testis/body weight ratio and reduction of tubular diameter were observed. Both groups of NaAsO(2)-exposed animals showed remarkable histopathological changes, such as sloughing of immature germ cells. Animals sacrificed after NaAsO(2) exposure showed decreased sperm motility, increased abnormal sperm morphology and decreased sperm viability. The effects of NaAsO(2) on sperm motility recovered to normal values after one spermatogenic cycle, while increased sperm abnormality was maintained. However, at this period, a decrease in acrosome integrity was detected. Concerning oxidative stress parameters, animals sacrificed after NaAsO(2) exposure showed a decreased selenium-dependent glutathione peroxidase activity, which was not detected after the recovery. Conversely, at this period, total glutathione peroxidase activity increased in exposed animals. These results demonstrate the toxic effects of NaAsO(2) on mice spermatogenesis and show the lack of recovery after one spermatogenic cycle. 相似文献
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