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41.
Marinho CC Voieta I Azeredo LM Nishi MP Batista TS Pereira AC Serufo JC Queiroz LC Ruiz-Guevara R Antunes CM Prata A Lambertucci JR 《Memórias do Instituto Oswaldo Cruz》2006,101(Z1):317-321
The best way to appraise the size of abdominal organs remains undefined. Herein we compare the size of liver and spleen in hepatosplenic schistosomiasis using clinical and ultrasound (US) examination, and the size of the organs measured by US with their visualization below the costal margin ("palpable by US"). For this study, 411 individuals from an endemic area for schistosomiasis mansoni in Brazil have been selected. We found that palpable spleens and left liver lobes are larger than non palpable ones. Also, 23% of normal spleens measured by US were palpable on clinical examination, and 22% of spleens increased in size on US were non palpable. A total of 21% of normal spleens were "palpable by US". We also found 54% of normal sized right liver lobes palpable on clinical examination, whilst 54% of the increased livers, measured by US, were non palpable. About 76% of normal right liver lobes were "palpable by US". We conclude that the association of clinical, ultrasound and magnetic resonance imaging (MRI) examinations, in the near future, should give the investigators the necessary tools to perform a more accurate clinical diagnosis of hepatosplenic schistosomiasis mansoni. 相似文献
42.
Freitas Natália Chagas Barreto Horllys Gomes Torres Luana Ferreira Freire Luciana Lima Rodrigues Leonardo Augusto Zebral Diniz Leandro Eugenio Cardamone Beijo Luiz Alberto Paiva Luciano Vilela 《Plant Cell, Tissue and Organ Culture》2019,137(3):599-611
Plant Cell, Tissue and Organ Culture (PCTOC) - The employment of biotechnology-based approaches such as somatic embryogenesis has been applied to several plants including Coffea sp. Despite the... 相似文献
43.
Luísa Czamanski Nora Cauã Antunes Westmann Leonardo Martins-Santana Luana de Fátima Alves Lummy Maria Oliveira Monteiro María-Eugenia Guazzaroni Rafael Silva-Rocha 《Microbial biotechnology》2019,12(1):125-147
When recombinant DNA technology was developed more than 40 years ago, no one could have imagined the impact it would have on both society and the scientific community. In the field of genetic engineering, the most important tool developed was the plasmid vector. This technology has been continuously expanding and undergoing adaptations. Here, we provide a detailed view following the evolution of vectors built throughout the years destined to study microorganisms and their peculiarities, including those whose genomes can only be revealed through metagenomics. We remark how synthetic biology became a turning point in designing these genetic tools to create meaningful innovations. We have placed special focus on the tools for engineering bacteria and fungi (both yeast and filamentous fungi) and those available to construct metagenomic libraries. Based on this overview, future goals would include the development of modular vectors bearing standardized parts and orthogonally designed circuits, a task not fully addressed thus far. Finally, we present some challenges that should be overcome to enable the next generation of vector design and ways to address it. 相似文献
44.
A M Cianciulli R Bovani C Leonardo F Iori A M Coletta R Marzano A Antenucci G M Gandolfo C Laurenti 《European journal of histochemistry : EJH》2001,45(1):65-71
We evaluated the genetic changes in bladder cancer biopsy by fluorescence in situ hybridization (FISH) and related them to stage and grade of the tumor, ploidy (FCM) and clinical outcome, to determine a simple method to identify tumors with a poorer prognosis. Using FISH the numerical aberrations of chromosomes 1, 7, 9, 17 in tumor's imprints of 70 patients with transitional cell cancer (TCC) were determined. First of all, the data demonstrated that the sensitivity of FISH in detecting quantitative DNA aberrations exceeds FCM's sensitivity. The frequency of chromosome 1 and 9 aberrations did not show significant differences in diploid and aneuploid tumors in different stage and grade. On the contrary, the chromosome 7 and 17 aneusomy showed greater differences between pT1 and pT2-3 tumors (p<0.032 and p<0.0006, respectively) than between stage pTa and pT1. In our investigation, an increasing number of aberrations was observed in all chromosomes examined in tumors of patients who afterwards underwent cystectomy and/or had recurrent tumors. These results suggest that chromosome 7 and 17 aneusomy could be predictive of adverse outcome in a subgroup of patients with superficial tumors at presentation. 相似文献
45.
Osvaldo Loquiha Niel Hens Leonardo Chavane Marleen Temmerman Marc Aerts 《Biometrical journal. Biometrische Zeitschrift》2013,55(5):647-660
Count data are very common in health services research, and very commonly the basic Poisson regression model has to be extended in several ways to accommodate several sources of heterogeneity: (i) an excess number of zeros relative to a Poisson distribution, (ii) hierarchical structures, and correlated data, (iii) remaining “unexplained” sources of overdispersion. In this paper, we propose hierarchical zero‐inflated and overdispersed models with independent, correlated, and shared random effects for both components of the mixture model. We show that all different extensions of the Poisson model can be based on the concept of mixture models, and that they can be combined to account for all different sources of heterogeneity. Expressions for the first two moments are derived and discussed. The models are applied to data on maternal deaths and related risk factors within health facilities in Mozambique. The final model shows that the maternal mortality rate mainly depends on the geographical location of the health facility, the percentage of women admitted with HIV and the percentage of referrals from the health facility. 相似文献
46.
Jilson L. Almeida-Junior Leonardo Gil-Santana Carolina A. M. Oliveira Simone Castro Aparecida S. Cafezeiro Carla Daltro Eduardo M. Netto Hardy Kornfeld Bruno B. Andrade 《PloS one》2016,11(4)
BackgroundDiabetes mellitus (DM) has been associated with increased risk for pulmonary tuberculosis (PTB) in endemic settings but it is unknown whether PTB risk is also increased by pre-DM. Here, we prospectively examined the association between glucose metabolism disorder (GMD) and PTB in patients with respiratory symptoms at a tuberculosis primary care reference center in Brazil.MethodsOral glucose tolerance test was performed and levels of fasting plasma glucose and glycohemoglobin (HbA1c) were measured in a cohort of 892 individuals presenting with respiratory symptoms of more than two weeks duration. Patients were also tested for PTB with sputum cultures. Prevalence of pre-DM and DM (based on HbA1c) was estimated and tested for association with incident PTB. Other TB risk factors including smoking history were analyzed.ResultsThe majority of the study population (63.1%) exhibited GMD based on HbA1c ≥5.7%. Patients with GMD had higher prevalence of PTB compared to normoglycemic patients. Individuals with DM exhibited increased frequency of TB-related symptoms and detection of acid-fast bacilli in sputum smears. Among patients with previous DM diagnosis, sustained hyperglycemia (HbA1c ≥7.0%) was associated with increased TB prevalence. Smoking history alone was not significantly associated with TB in our study population but the combination of smoking and HbA1c ≥7.0% was associated with 6 times higher odds for PTB.ConclusionsSustained hyperglycemia and pre-DM are independently associated with active PTB. This evidence raises the question whether improving glycemic control in diabetic TB patients would reduce the risk of TB transmission and simultaneously reduce the clinical burden of disease. A better understanding of mechanisms underlying these associations, especially those suggesting that pre-DM may be a factor driving susceptibility to TB is warranted. 相似文献
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49.
McPherson JP Tamblyn L Elia A Migon E Shehabeldin A Matysiak-Zablocki E Lemmers B Salmena L Hakem A Fish J Kassam F Squire J Bruneau BG Hande MP Hakem R 《The EMBO journal》2004,23(18):3677-3688
The Drosophila melanogaster warts/lats tumour suppressor has two mammalian counterparts LATS1/Warts-1 and LATS2/Kpm. Here, we show that mammalian Lats orthologues exhibit distinct expression profiles according to germ cell layer origin. Lats2(-/-) embryos show overgrowth in restricted tissues of mesodermal lineage; however, lethality ultimately ensues on or before embryonic day 12.5 preceded by defective proliferation. Lats2(-/-) mouse embryonic fibroblasts (MEFs) acquire growth advantages and display a profound defect in contact inhibition of growth, yet exhibit defective cytokinesis. Lats2(-/-) embryos and MEFs display centrosome amplification and genomic instability. Lats2 localizes to centrosomes and overexpression of Lats2 suppresses centrosome overduplication induced in wild-type MEFs and reverses centrosome amplification inherent in Lats2(-/-) MEFs. These findings indicate an essential role of Lats2 in the integrity of processes that govern centrosome duplication, maintenance of mitotic fidelity and genomic stability. 相似文献
50.
D'Addio F Riella LV Mfarrej BG Chabtini L Adams LT Yeung M Yagita H Azuma M Sayegh MH Guleria I 《Journal of immunology (Baltimore, Md. : 1950)》2011,187(9):4530-4541
Fetomaternal tolerance has been shown to depend both on regulatory T cells (Tregs) and negative signals from the PD1-PDL1 costimulatory pathway. More recently, IL-17-producing T cells (Th17) have been recognized as a barrier in inducing tolerance in transplantation. In this study, we investigate the mechanisms of PDL1-mediated regulation of fetomaternal tolerance using an alloantigen-specific CD4(+) TCR transgenic mouse model system (ABM-tg mouse). PDL1 blockade led to an increase in embryo resorption and a reduction in litter size. This was associated with a decrease in Tregs, leading to a lower Treg/effector T cell ratio. Moreover, PDL1 blockade inhibited Ag-specific alloreactive T cell apoptosis and induced apoptosis of Tregs and a shift toward higher frequency of Th17 cells, breaking fetomaternal tolerance. These Th17 cells arose predominantly from CD4(+)Foxp3(-) cells, rather than from conversion of Tregs. Locally in the placenta, similar decrease in regulatory and apoptotic markers was observed by real-time PCR. Neutralization of IL-17 abrogated the anti-PDL1 effect on fetal survival rate and restored Treg numbers. Finally, the adoptive transfer of Tregs was also able to improve fetal survival in the setting of PDL1 blockade. This is to our knowledge the first report using an alloantigen-specific model that establishes a link between PDL1, Th17 cells, and fetomaternal tolerance. 相似文献