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71.
Simone C. M. Ribeiro Lia Lima Gomes Eduardo P. Amaral Marcelle R. M. Andrade Fabricio M. Almeida Andreza L. Rezende Ver?nica R. Lanes Eulógio C. Q. Carvalho Philip N. Suffys Igor Mokrousov Elena B. Lasunskaia 《Journal of clinical microbiology》2014,52(7):2615-2624
Strains of the Beijing genotype family of Mycobacterium tuberculosis are a cause of particular concern because of their increasing dissemination in the world and their association with drug resistance. Phylogenetically, this family includes distinct ancient and modern sublineages. The modern strains, contrary to the ancestral counterparts, demonstrated increasing prevalence in many world regions that suggest an enhanced bacterial pathogenicity. We therefore evaluated virulence of modern versus ancient Beijing strains with similar epidemiological and genotype characteristics. For this, we selected six strains that had very similar 24-locus mycobacterial interspersed repetitive-unit–variable-number tandem-repeat (MIRU-VNTR) typing profiles and belonged to the region of difference 181 (RD181) subgroup but differed using markers (mutT2 and mutT4 genes and NTF locus) that discriminate between modern and ancient Beijing sublineages. The strains were isolated from native patients in Brazil and Mozambique, countries with a low prevalence of Beijing strains. The virulence levels of these strains were determined in models of pulmonary infection in mice and in vitro macrophage infection and compared with that of a strain from Russia, part of the epidemic and hypervirulent Beijing clone B0/W148, and of the laboratory strain H37Rv. The results showed that two of the three modern Beijing strains were highly pathogenic, exhibiting levels of virulence comparable with that of the epidemic Russian strain. In contrast, all isolates of the ancient sublineage displayed intermediate or low virulence. The data obtained demonstrate that the strains of the modern Beijing sublineage are more likely to exhibit highly virulent phenotypes than ancient strains and suggest that genetic alterations characteristic of the modern Beijing sublineage favor selection of highly virulent bacteria. 相似文献
72.
Eliane Gouvêa de Oliveira Barros Antonio Palumbo Jr. Pedro Lucas Prado Mello Rômulo Medina de Mattos Julianna Henriques da Silva Bruno Pontes Nathan Bessa Viana Rackele Ferreira do Amaral Flavia Regina Souza Lima Nathalia Meireles da Costa Celia Yelimar Palmero Leandro Miranda-Alves Christina Maeda Takiya Luiz Eurico Nasciutti 《Clinical & experimental metastasis》2014,31(4):461-474
Tumor establishment, growth, and survival are supported by interactions with microenvironment components. Here, we investigated whether the interactions between prostate cancer cells and cortical astrocytes are associated to a potential role for astrocytes in tumor establishment. We demonstrate that astrocytes interact in vitro with prostatic cancers cells derived from different metastatic sites. Astrocytes and their secreted extracellular matrix, stimulate DU145 cell (a brain-derived prostate tumor cell line) proliferation while inhibiting cell death and modulating the expression of several genes related to prostate cancer progression, suggesting the activation of EMT process in these cells. In contrast, DU145 cells and their conditioned medium inhibited cell proliferation and induced cell death of astrocytes. On the other hand, the astrocytes were unable to significantly induce an increment of LNCaP cell (a lymph node-derived prostate tumor cell line) proliferative activity. In addition, LNCaP cells were also unable to induce cell death of astrocytes. Thus, we believe that DU145 cells, but not LNCaP cells, present an even more aggressive behavior when interacting with astrocytes. These results provide an important contribution to the elucidation of the cellular mechanisms involved in the brain microenvironment colonization. 相似文献
73.
Adriano Fernandes Jo?o Ettinger Fabiano Amaral Maria José Ramalho Rodrigo Alves Norma Sueli Pinheiro Módolo 《Clinics (S?o Paulo, Brazil)》2014,69(10):655-659
OBJECTIVES:
Video laparoscopic bariatric surgery is the preferred surgical technique for treating morbid obesity. However, pneumoperitoneum can pose risks to the kidneys by causing a decrease in renal blood flow. Furthermore, as in other surgical procedures, laparoscopic bariatric surgery triggers an acute inflammatory response. Neutrophil gelatinase-associated lipocalin is an early and accurate biomarker of renal injury, as well as of the inflammatory response. Anesthetic drugs could offer some protection for the kidneys and could attenuate the acute inflammatory response from surgical trauma. The objective of this study was to compare the effects of two types of anesthetics, propofol and sevoflurane, on the serum levels of neutrophil gelatinase-associated lipocalin during the perioperative period in laparoscopic bariatric surgery.METHODS:
Sixty-four patients scheduled for laparoscopic bariatric surgery were randomized into two anesthesia groups and were administered either total intravenous anesthesia (propofol) or inhalation anesthesia (sevoflurane). In the perioperative period, blood samples were collected at three time points (before anesthesia, 6 hours after pneumoperitoneum and 24 hours after pneumoperitoneum) and urine output was measured for 24 hours. Acute kidney injuries were evaluated by examining both the clinical and laboratory parameters during the postoperative period. The differences between the groups were compared using non-parametric tests. ReBEC (http://www.ensaiosclinicos.gov.br/rg/recruiting/): RBR-8wt2fyRESULTS:
None of the patients developed an acute kidney injury during the study and no significant differences were found between the serum neutrophil gelatinase-associated lipocalin levels of the groups during the perioperative period.CONCLUSION:
The choice of anesthetic drug, either propofol or sevoflurane, did not affect the serum levels of neutrophil gelatinase-associated lipocalin during the perioperative period in laparoscopic bariatric surgery. 相似文献74.
75.
76.
Mariana Amaral Raposo Nathalia Sernizon Guimares Unaí Tupinambs 《Clinical Medicine & Research》2020,18(4):120
Background:Dyslipidemia and central obesity are the main components of metabolic syndrome, which represent important risk factors for cardiovascular diseases in people living with human immunodeficiency virus (HIV). The lipid accumulation product (LAP) index has been shown in studies as an efficient marker of metabolic syndrome in general adult population and its applicability in HIV-infected population is not discussed. We aimed to assess the accuracy of the LAP index to identify metabolic syndrome in people living with HIV.Methods:It is a cross-sectional study with 141 HIV-infected patients on antiretroviral therapy, conducted in a reference centre of infectious diseases in southeast Brazil. Evaluations included LAP index, anthropometric measurements and clinical and laboratorial variables. Metabolic syndrome was defined by International Diabetes Federation (IDF) criteria.Results:The prevalence of metabolic syndrome in our sample was 10.6%. A positive and significant correlation was found between the metabolic syndrome and LAP (r=0.401; P<0.01), metabolic syndrome and body mass index (r=0.361; P<0.01) and metabolic syndrome and waist circumference (r=0.427; P<0.01) in our sample. The analysis of the receiver-operating characteristic (ROC) curve revealed that the best cut-off value for LAP index to define metabolic syndrome was 59.4 (sensitivity 80%, specificity 79% and area under the curve (AUC) of 0.875. In female and male, analysis of the ROC curve revealed that the best cut-off value for LAP index to define metabolic syndrome was 56.3 (sensitivity 100%, specificity 82% and AUC of 0.929) and 52.0 (sensitivity 78%, specificity 74% and AUC of 0.838), respectively.Conclusion:Despite the low prevalence of metabolic syndrome in our sample, the ROC curves analyzes demonstrated a good diagnostic accuracy as an additional screening tool of metabolic syndrome according to the IDF. 相似文献
77.
Sara Moreira Pedro Moreira Ana S. Sousa Rita S. Guerra Cludia Afonso Alejandro Santos Nuno Borges Teresa F. Amaral Patrícia Padro 《Nutrients》2022,14(1)
Despite the well-known benefits of the Mediterranean Diet (MedDiet), data on the sodium intake is scarce. This study aimed to quantify the association between sodium excretion and the adherence to the MedDiet in the elderly. A representative sample of 1500 Portuguese adults (≥65 years) was assessed (1321 were eligible for the present analysis). A 24 h urine sample was collected and analysed for creatinine and sodium. Excessive sodium intake was defined as above 2000 mg/day. The adherence to the MedDiet was assessed by the PREDIMED. A binary logistic regression model was conducted to evaluate the association between urinary sodium excretion and the adherence to the MedDiet. Odds Ratios (OR) and respective 95% Confidence Intervals (95% CI) were calculated. Excessive sodium excretion was observed in 80.0% of men and 91.5% of women whereas a high adherence to the MedDiet was reported by 42.2% of women and 46.4% of men. After adjusting for confounders, excessive sodium excretion was associated with a high adherence to the MedDiet in men (OR = 1.94; 95% CI: 1.03–3.65) but not in women. These results show that the MedDiet can be an important source of sodium and highlight the need for implementing strategies to reduce sodium intake when following a MedDiet. 相似文献
78.
Ilyes Dammak Carla Giovana Luciano Luis Jaime Prez-Crdoba Maria Lúcia Monteiro Carlos Adam Conte-Junior Paulo Jos do Amaral Sobral 《RSC advances》2021,11(45):28148
The attention towards active films has increased due to consumer demand for high-quality foods without chemical additives. Active biopolymer-based films have shown great potential for active films by impacting food safety, acting as the carriers of various natural antioxidant and antimicrobial compounds, and decreasing environmental pollution from petrol-derived packaging materials. However, there is a wide range of challenges concerning the different characteristics of biopolymers and plasticizers, often hygroscopic/hydrophilic, compared to numerous lipophilic bioactive compounds. Therefore, recent studies have focused on applying oil-in-water emulsion-based systems to enhance the lipophilic bioactive compounds'' dispersibility into the film matrix, improving their performance. It is worth emphasizing that resulting complex systems give rise to new challenges such as (i) dispersion technology of the bioactive compounds with minimum adverse effects on its bioactivities, (ii) interactions between different components of the active films, giving rise to new physicochemical properties, and (iii) the change of the diffusion properties of bioactive compounds into the active films, resulting in different release properties. These challenges are profound and critically discussed in this review, as well as the encapsulation techniques employed in preparing emulsions loaded with lipophilic bioactive compounds for the active film development. An outlook of future directions in the research, development, and application of these active films are given.The attention towards active films has increased due to consumer demand for high-quality foods without chemical additives. 相似文献
79.
John Lennon Silva-Cunha Israel Leal Cavalcante Caio Csar da Silva Barros Fernanda Arago Felix Luan Borges Venturi Larissa Santos Amaral Rolim Csar Luis Porpino Santos da Silva-Júnior Emanuel Mendes Sousa ricka Janine Dantas da Silveira Michelle Agostini Mrio Jos Romanach Oslei Paes de Almeida Sílvia Ferreira de Sousa Bruno Augusto Benevenuto de Andrade 《Medicina oral, patología oral y cirugía bucal》2022,27(1):e35