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51.
Priscilla Rocío-Bautista Vernica Pino Juan H. Ayala Catalina Ruiz-Prez Oriol Vallcorba Ana M. Afonso Jorge Pasn 《RSC advances》2018,8(55):31304
The CIM-80 material (aluminum(iii)-mesaconate) has been synthetized in high yield through a novel green procedure involving water and urea as co-reactants. The CIM-80 material exhibits good thermal stability with a working range from RT to 350 °C with a small contraction upon desolvation. Moreover, this material is stable in water at different pH values (1–10) for at least one week, and shows a LC50 value higher than 2 mg mL−1. The new material has been tested in a microextraction methodology for the monitoring of up to 22 water pollutants while presenting little environmental impact: only 20 mg of CIM-80 and 500 μL of acetonitrile are needed per analysis. The analytical performance of the CIM-80 in the microextraction strategy is similar to or even better for several pollutants than that of MIL-53(Al). The average extraction efficiencies range from ∼20% for heavy polycyclic aromatic hydrocarbons to ∼70–100% for the lighter ones. In the case of the emerging contaminants, the average extraction efficiency can reach values up to 70% for triclosan and carbamazepine.A low cytotoxic MOF prepared with an environmental-friendly approach, as a novel extractant of water pollutants using a microextraction method. 相似文献
52.
This paper presents a new joining method by a forming process for attaching sheets to tube ends. The process consists of two different forming stages carried out sequentially in a single stroke. Firstly, the free tube end is flared by compression with a contoured die, then is squeezed (indented) against the sheet surface to create a mechanical interlocking. The new process is carried out at an ambient temperature and, in contrast to existing joining by forming operations based on tube expansion, it avoids seal welds, tube protrusions above the sheet surfaces, and machining of grooves on the sheet holes to obtain the form-fit joints. The paper starts by analyzing the process deformation mechanics and its main operating variables and finishes by presenting examples that demonstrate its effectiveness for attaching sheets to tube ends made from polyvinylchloride and aluminum. Experimental and numerical simulation work provides support to the presentation. 相似文献
53.
Campino L Pratlong F Abranches P Rioux JA Santos-Gomes G Alves-Pires C Cortes S Ramada J Cristovão JM Afonso MO Dedet JP 《Tropical medicine & international health : TM & IH》2006,11(11):1708-1714
This study reports isoenzyme polymorphism of Leishmania strains isolated in different regions of Portugal between 1982 and 2005. A total of 213 strains were obtained from cases of visceral and cutaneous leishmaniasis isolated from immunocompetent patients (adults and children) and immunocompromised adults, as well as from dogs and sandflies. Four zymodemes were identified: MON-1, MON-24, MON-29 and MON-80. Zymodeme MON-1 was identified in 96.7% of the strains, predominating in both immunocompetent and immunocompromised human patients, and it was the only zymodeme isolated from dogs. Isoenzyme diversity in HIV-infected patients was higher than in the immunocompetent group, in which all the strains from visceral leishmaniasis were MON-1. The domestic dog was confirmed as the reservoir host of zoonotic leishmaniasis in Portugal and Phlebotomus perniciosus and Phlebotomus ariasi as vectors. The overall low enzyme polymorphism observed in the Portuguese foci contrasts with the neighbouring foci in Spain. 相似文献
54.
55.
Lutzomyia longipalpis salivary gland homogenate impairs cytokine production and costimulatory molecule expression on human monocytes and dendritic cells 总被引:4,自引:0,他引:4 下载免费PDF全文
Costa DJ Favali C Clarêncio J Afonso L Conceição V Miranda JC Titus RG Valenzuela J Barral-Netto M Barral A Brodskyn CI 《Infection and immunity》2004,72(3):1298-1305
In this report, we describe an investigation of the effects of Lutzomyia longipalpis sand fly salivary gland homogenates (SGH) on cytokine production and expression of costimulatory molecules on human monocytes, macrophages (Ms), and dendritic cells (DCs). SGH of L. longipalpis induced an increase in interleukin-6 (IL-6), IL-8 and IL-12p40 production but a decrease in tumor necrosis factor alpha and IL-10 production by lipopolysaccharida (LPS)-stimulated monocytes. We also examined the expression of costimulatory molecules on the surface of monocytes, Ms, and DCs. Whereas SGH affected the expression of these molecules on monocytes and Ms, it had little effect on these molecules on DCs. However, when DCs were generated from human monocytes in the presence of SGH, SGH inhibited the expression of costimulatory molecules. In addition, a decrease in the maturation of DCs induced by CD40L was observed in the presence of SGH. Finally, preincubating SGH with human sera containing anti-SGH-specific antibodies abolished the effects of SGH on cytokine production by LPS-stimulated monocytes. 相似文献
56.
Diel DG Susta L Cardenas Garcia S Killian ML Brown CC Miller PJ Afonso CL 《Journal of clinical microbiology》2012,50(2):378-387
Newcastle disease (ND) is one of the most important diseases of poultry, negatively affecting poultry production worldwide. The disease is caused by Newcastle disease virus (NDV) or avian paramyxovirus type 1 (APMV-1), a negative-sense single-stranded RNA virus of the genus Avulavirus, family Paramyxoviridae. Although all NDV isolates characterized to date belong to a single serotype of APMV-1, significant genetic diversity has been described between different NDV isolates. Here we present the complete genome sequence and the clinicopathological characterization of a virulent Newcastle disease virus isolate (NDV-Peru/08) obtained from poultry during an outbreak of ND in Peru in 2008. Phylogenetic reconstruction and analysis of the evolutionary distances between NDV-Peru/08 and other isolates representing established NDV genotypes revealed the existence of large genomic and amino differences that clearly distinguish this isolate from viruses of typical NDV genotypes. Although NDV-Peru/08 is a genetically distinct virus, pathogenesis studies conducted with chickens revealed that NDV-Peru/08 infection results in clinical signs characteristic of velogenic viscerotropic NDV strains. Additionally, vaccination studies have shown that an inactivated NDV-LaSota/46 vaccine conferred full protection from NDV-Peru/08-induced clinical disease and mortality. This represents the first complete characterization of a virulent NDV isolate from South America. 相似文献
57.
Two parallel plate ionization chambers (inserted in slab phantoms) recently assembled at IPEN were studied in relation to their operational characteristics for use in quality control of X-ray beams, mammography level. The chambers present only one difference: one has an inner collecting electrode made of graphite and the other, of aluminum. These chambers make up a tandem system, which may be employed to verify X-ray beams energy constancy, by the confirmation of half-value layers and effective energies, and to determinate air kerma rates. The chambers presented good results for the operational tests, as recommended internationally. 相似文献
58.
Mina Cintho Ozahata Grier P. Page Yuelong Guo João Eduardo Ferreira Carla Luana Dinardo Anna Bárbara F. Carneiro-Proietti Paula Loureiro Rosimere Afonso Mota Daniela O.W. Rodrigues André Rolim Belisario Claudia Maximo Miriam V. Flor-Park Brian Custer Shannon Kelly Ester Cerdeira Sabino 《The journal of sexual medicine》2019,16(12):1988-1999
IntroductionPriapism is the persistent and painful erection of the penis and is a common sickle cell disease (SCD) complication.AimThe goal of this study was to characterize clinical and genetic factors associated with priapism within a large multi-center SCD cohort in Brazil.MethodsCases with priapism were compared to SCD type-matched controls within defined age strata to identify clinical outcomes associated with priapism. Whole blood single nucleotide polymorphism genotyping was performed using a customized array, and a genome-wide association study (GWAS) was conducted to identify single nucleotide polymorphisms associated with priapism.Main Outcome MeasureOf the 1,314 male patients in the cohort, 188 experienced priapism (14.3%).ResultsPriapism was more common among older patients (P = .006) and more severe SCD genotypes such as homozygous SS (P < .0001). In the genotype- and age-matched analyses, associations with priapism were found for pulmonary hypertension (P = .05) and avascular necrosis (P = .01). The GWAS suggested replication of a previously reported candidate gene association of priapism for the gene transforming growth factor beta receptor 3 (TGFBR3) (P = 2 × 10?4).Clinical ImplicationsOlder patients with more severe genotypes are at higher risk of priapism, and there is a lack of consensus on standard treatment strategies for priapism in SCD.Strengths & LimitationsThis study characterizes SCD patients with any history of priapism from a large multi-center cohort. Replication of the GWAS in an independent cohort is required to validate the results.ConclusionThese findings extend the understanding of risk factors associated with priapism in SCD and identify genetic markers to be investigated in future studies to further elucidate priapism pathophysiology.Ozahata M, Page GP, Guo Y, et al. Clinical and Genetic Predictors of Priapism in Sickle Cell Disease: Results from the Recipient Epidemiology and Donor Evaluation Study III Brazil Cohort Study. J Sex Med 2019;16:1988–1999. 相似文献
59.
L.A. Afonso W.M. Rocha F.N. Carestiato E.A. Dobao L.F. Pesca M.R.L. Passos S.M.B. Cavalcanti 《Brazilian journal of medical and biological research》2013,46(6):533-538
Cervical cancer is a major source of illness and death among women worldwide and
genital infection with oncogenic human papillomavirus (HPV) its principal cause.
There is evidence of the influence of the male factor in the development of
cervical neoplasia. Nevertheless, the pathogenic processes of HPV in men are
still poorly understood. It has been observed that different HPV types can be
found among couples. The objective of the present study was to investigate HPV
infections in female patients (n = 60 females/group) as well as in their sexual
partners and to identify the concordance of HPV genotypes among them. By using
the polymerase chain reaction, we detected a 95% prevalence of HPV DNA in women
with cervical intraepithelial neoplasia (CIN) compared to 18.3% in women with
normal cervical epithelium, with a statistically significant difference (P <
0.001). The HPV DNA prevalence was 50% in male partners of women with CIN and
16.6% in partners of healthy women. In the control group (healthy women), only 9
couples were simultaneously infected with HPV, and only 22.2% of them had the
same virus type, showing a weak agreement rate (kappa index = 0.2). Finally, we
observed that HPV DNA was present in both partners in 30 couples if the women
had CIN, and among them, 53.3% shared the same HPV type, showing moderate
agreement, with a kappa index of 0.5. This finding supports the idea of
circulation and recirculation of HPV among couples, perpetuating HPV in the
sexually active population, rather than true recurrences of latent
infections. 相似文献