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21.
Terahertz time-domain spectroscopy (THz-TDS) was employed for estimation of intrinsic dielectric loss of Zr0.8Sn0.2TiO4 (ZST) ceramics. Single-phase ZST dielectric resonators (DRs) with various synthesis parameters and, consequently, different extrinsic losses, were prepared by conventional ceramic technology. Even though the DRs exhibit a similar microstructure, their quality factor (Q is the inverse of dielectric loss tangent) measured in microwave (MW) domain at 6 GHz varies between 2500 and 8400. On the other hand, it was found that the THz dielectric loss is less sensitive to the sample preparation. The intrinsic losses (Q × f ~60 THz) of the ZST ceramics have been derived from THz data. 相似文献
22.
Renata Duarte da Silva Cezar Priscila Mayrelle da Silva Castanha Naishe Matos Freire Carla Mola Rodrigo Feliciano do Carmo Marli Tenrio Cordeiro Paulo Baptista Luydson Richardson Silva Vasconcelos Patrícia Moura Vanessa Gabryelle da Silva Teixeira 《International journal of immunogenetics》2020,47(4):351-358
Single nucleotide polymorphisms (SNPs) in immune‐related genes have been shown to play a role in driving the development of the severe phenotypes of dengue virus (DENV) infection. We assessed the association between IFNL3 gene SNP (rs12979860) and dengue clinical outcomes in children. Patients with dengue‐related symptoms (aged 1–15 years) admitted at a public hospital in Northeast Brazil were invited to participate. The association between rs12979860 polymorphism and dengue classification and clinical signs and symptoms were analysed. A total of 206 DENV‐infected children were included: 53.4% of the infections were classified as severe dengue. The T allele carriers had higher risk of developing severe dengue when compared to CC genotype carriers (OR: 1.81; 95% CI: 0.98–3.32 p = .054). The T allele carriers also showed longer fever episodes when compared to patients with the CC genotype (OR: 1.90; 95%CI: 1.07–3.38; p = .027). On the other hand, the ones carrying the CT/TT genotype had 70% lower chance of developing thrombocytopenia when compared to those with the CC genotype (OR: 0.30; 95%CI: 0.08–0.88; p = .042). Our findings demonstrated that the T allele carriers of the IFNL3 gene had higher risk of developing severe dengue, suggesting a link between IFN‐λ expression and DENV immunopathogenesis. 相似文献
23.
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
24.
Dentin hypersensitivity is a common painful condition observed in clinics. Dietary habits have been much associated with its development and persistence during and following periodontal treatment. The aim of this in vitro study was to evaluate the influence of vinegars on the removal of smear layer and exposure of dentinal tubules. Extracted human teeth were submitted to manual scaling with Gracey curettes in order to remove the cementum as well as to form a smear layer. Dentin samples with 3 mm(2) were obtained and distributed into six experimental groups: one control and five types of vinegars (alcohol, apple, rice, white wine and balsamic). Each group included two methods of vinegar application: topical and friction. After routine preparation for SEM analysis, photomicrographs were assessed by a calibrated and blind examiner using an appropriate index system. Kruskal-Wallis test indicated a significant influence of vinegars on smear layer removal. There was a statistically significant difference between groups treated with apple, white and rice vinegars and the control group (p < 0.05). Nevertheless, Mann-Whitney test indicated that removal of smear layer did not vary with the method of application (topical versus friction) for any of the tested substances. We can conclude that the contact of vinegar may remove smear layer and expose dentinal tubules, regardless of the type of application. However, balsamic vinegar was associated with less removal of smear layer after both methods of application. 相似文献
25.
26.
Oral glutamine and the healing of colonic anastomoses in rats 总被引:2,自引:0,他引:2
da Costa MA Campos AC Coelho JC de Barros AM Matsumoto HM 《JPEN. Journal of parenteral and enteral nutrition》2003,27(3):182-5; discussion 185-6
BACKGROUND: Recent evidence has suggested that glutamine is one of the primary energy sources of the colon. The aim of this study was to evaluate the effects of oral glutamine supplementation on the healing of colonic anastomoses in rats. METHODS: Forty-eight adult male Wistar rats, weighing 174.41 +/- 37.39 g, were housed in individual cages. All rats had free access to water and standard rat chow. The rats were randomized to receive daily, for 7 days before the operation and during the postoperative period, 10% L-glutamine (GLN group) or 10% glycine (GLY group) in isonitrogenous and isovolumetric solutions (1.5 g/kg per day), through an orogastric tube. On the eighth day, rats were anesthetized and subjected to 2 colonic transections, one 6 cm distal from the ileocecal valve and another 5 cm distal from the first transection. Bowel continuity was restored by 2 end-to-end, single layer, everted, anastomoses with 8 interrupted sutures (6-0 nylon). After the operation, the rats were kept in individual cages and had free access to water and rat chow. One-half of the rats in each group were killed either on postoperative day 3 or 8, and the 2 colonic anastomoses of each animal were resected and stored in 0.9% saline and 10% formalin for tensile strength and histologic (hematoxylineosin and collagen densitometry) studies, respectively. Student's t-test and Kruskal Wallis tests were used for statistical analysis. RESULTS: Total rupture strength was significantly higher in the GLN group (GLN: 0.068 +/- 0.045 kgf versus GLY: 0.042 +/- 0.027 kgf, p = .04). The mean monocytes infiltrate was significantly smaller in the GLN group (p = .04). The collagen densitometry analysis demonstrated greater percent area of type I (mature) in the GLN group compared with GLY (58.65 +/- 11.70% versus 41.79 +/- 10.54%, p = .0000), respectively. Subgroup analyses according to the day of rat death were still significant: GLN 3: 54.22 +/- 10.02% versus GLY 3: 41.92 +/- 13.31% (p = .04) and GLN 8: 62.63 +/- 12.13% versus GLY 8: 41.67 +/- 7.69% (p = .0004). Type III collagen (immature) percent area was significantly smaller in the GLN group's colonic anastomoses (GLN: p = .0000; GLN 3: p = .04 and GLN 8: p = .0003, respectively). CONCLUSIONS: Perioperative oral glutamine supplementation increases total rupture strength and improves the percent area of mature collagen at the anastomoses sites on postoperative days 3 and 8. 相似文献
27.
Using Webster's technique for treating gynecomastia, the removal of the excess breast tissue is facilitated by the use of liposuction introduced through the axillary incision. In the case of pseudogynecomastia, only liposuction, via the axillary, approach is recommended. 相似文献
28.
Benhur Davi Henz Thais A. do Nascimento Cristiano de O. Dietrich Charles Dalegrave Veruska Hernandes Cezar E. Mesas Luiz R. Leite Claudio Cirenza Samuel J. Asirvatham Angelo Amato Vincenzo de Paola 《Journal of interventional cardiac electrophysiology》2009,26(3):195-205
Background and Aims
Slow conduction scarred areas are related with ventricular tachycardia (VT) arrhythmogenesis in nonischemic cardiomyopathy. The purpose of this study was to characterize the substrate in both epicardial and endocardial surfaces of the left ventricle and to evaluate the effectiveness of substrate mapping and ablation for VT in Chagas cardiomyopathy. 相似文献29.
Magnolia Astrid Pretell Bocángel Uirá Souto Melo Leandro Ucela Alves Eliete Pardono Naila Cristina Vilaça Lourenço Humberto Vicente Cezar Marcolino Paulo Alberto Otto Regina Célia Mingroni-Netto 《European journal of medical genetics》2018,61(6):348-354
This paper deals with the molecular investigation of Waardenburg syndrome (WS) in a sample of 49 clinically diagnosed probands (most from southeastern Brazil), 24 of them having the type 1 (WS1) variant (10 familial and 14 isolated cases) and 25 being affected by the type 2 (WS2) variant (five familial and 20 isolated cases). Sequential Sanger sequencing of all coding exons of PAX3, MITF, EDN3, EDNRB, SOX10 and SNAI2 genes, followed by CNV detection by MLPA of PAX3, MITF and SOX10 genes in selected cases revealed many novel pathogenic variants. Molecular screening, performed in all patients, revealed 19 causative variants (19/49?=?38.8%), six of them being large whole-exon deletions detected by MLPA, seven (four missense and three nonsense substitutions) resulting from single nucleotide substitutions (SNV), and six representing small indels. A pair of dizygotic affected female twins presented the c.430delC variant in SOX10, but the mutation, imputed to gonadal mosaicism, was not found in their unaffected parents. At least 10 novel causative mutations, described in this paper, were found in this Brazilian sample. Copy-number-variation detected by MLPA identified the causative mutation in 12.2% of our cases, corresponding to 31.6% of all causative mutations. In the majority of cases, the deletions were sporadic, since they were not present in the parents of isolated cases. Our results, as a whole, reinforce the fact that the screening of copy-number-variants by MLPA is a powerful tool to identify the molecular cause in WS patients. 相似文献