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排序方式: 共有5415条查询结果,搜索用时 29 毫秒
51.
Mariana Cárdenas-González Octavio Gaspar-Ramírez Francisco J. Pérez-Vázquez Jorge Alejandro Alegría-Torres Roberto González-Amaro Iván N. Pérez-Maldonado 《Experimental and toxicologic pathology》2013,65(5):661-665
In a recent study, our group demonstrated that when peripheral blood mononuclear cells (PBMCs) were treated “in vitro” with p,p′-DDE, a DDT metabolite, an antioxidant response and biomarkers of inflammation were induced at the mRNA level, indicating a proinflammatory state. Thus, the aim of this study was to evaluate the induction of proinflammatory molecules at the protein level in PBMCs exposed to p,p′-DDE “in vitro”. The main finding was that “in vitro” exposure to p,p′-DDE enhanced the expression of proinflammatory cytokines (TNF-α, IL-1β, IL-6) at the protein level in PBMCs. We also observed COX-2 induction at the protein level. Considering that p,p′-DDE has been identified as a persistent metabolite and is frequently found in the population, it is important to evaluate early inflammation biomarkers in populations exposed to DDT and to estimate the true risk of inflammatory disease development. 相似文献
52.
Xerophilic fungal species of the genus Aspergillus are economically highly relevant due to their ability to grow on low water activity substrates causing spoilage of stored goods and animal feeds. These fungi can synthesize a variety of secondary metabolites, many of which show animal toxicity, creating a health risk for food production animals and to humans as final consumers, respectively. Animal feeds used for rabbit, chinchilla and rainbow trout production in Argentina were analysed for the presence of xerophilic Aspergillus section Aspergillus species. High isolation frequencies (>60%) were detected in all the studied rabbit and chinchilla feeds, while the rainbow trout feeds showed lower fungal charge (25%). These section Aspergillus contaminations comprised predominantly five taxa. Twenty isolates were subjected to taxonomic characterization using both ascospore SEM micromorphology and two independent DNA loci sequencing. The secondary metabolite profiles of the isolates were determined qualitatively by HPLC-MS. All the isolates produced neoechinulin A, 17 isolates were positive for cladosporin and echinulin, and 18 were positive for neoechinulin B. Physcion and preechinulin were detected in a minor proportion of the isolates. This is the first report describing the detailed species composition and the secondary metabolite profiles of Aspergillus section Aspergillus contaminating animal feeds. 相似文献
53.
Camila Fernanda Novak Pinheiro de Freitas Fabiane Mulinari-Brenner Hanae Rafaela Fontana Arthur Conelian Gentili Mariana Hammerschmidt 《Anais brasileiros de dermatologia》2013,88(4):627-630
Ichthyoses are a common group of keratinization disorders. A non-inflammatory
generalized persistent skin desquamation is observed. It is characterized by
increased cell turnover, thickening of the stratum corneum and functional changes of
sebaceous and sweat glands. All of these favor fungal proliferation. Dermatophytes
may infect skin, hair and nails causing ringworm or tinea. They have the ability to
obtain nutrients from keratinized material. One of its most prevalent genera is
Trichophyton rubrum. Although tineas and ichthyoses are quite common, the association
of the two entities is rarely reported in the literature. Three cases of ichthyosis
associated with widespread infection by T. rubrum are presented. Resistance to
several antifungal treatments was responsible for worsening of ichthyosis signs and
symptoms. 相似文献
54.
55.
Mariana G. Braz Leandro G. Braz Marina A. Mazoti Matheus F. Pinotti Maria Inês M. C. Pardini José R. C. Braz Daisy M. F. Salvadori 《Environmental and molecular mutagenesis》2012,53(1):70-77
Propofol, which is widely used as an intravenous anesthetic, has a phenolic structure similar to that of α‐tocopherol with antioxidant properties that could prevent genotoxicity and cytotoxicity in lymphocytes of anesthetized patients. The aims of this study were to evaluate oxidative DNA damage and apoptosis in lymphocytes and the expression of DNA repair genes in blood cells from patients undergoing elective surgery under anesthesia with propofol. Twenty healthy adults of both genders (18–50 years old) who were scheduled for otorhinological surgery were enrolled in this study. Blood samples were collected before anesthesia induction (T1‐baseline), 120 min after anesthesia induction (T2), and on the first postoperative day (T3). Oxidative DNA damage in peripheral lymphocytes was assessed using the comet assay. Lymphocytes were phenotyped as T helper or cytotoxic T cells, and apoptosis was evaluated using flow cytometry. The expression of DNA repair genes (hOGG1 and XRCC1) was assessed by quantitative polymerase chain reaction. A reduction in the level of oxidized purines in DNA (P < 0.01) was observed 120 min after anesthesia induction, and reduced apoptosis of T helper cells was observed 120 min after anesthesia induction and on the first postoperative day. Down‐regulation of hOGG1 and XRCC1 gene expression was observed on the first postoperative day. In conclusion, patients undergoing non‐invasive surgery under propofol anesthesia presented lower levels of oxidized purines and apoptosis of T helper lymphocytes. Furthermore, anesthesia with propofol did not directly influence the expression of the DNA repair genes hOGG1 and XRCC1 in blood cells. © Environ. Mol. Mutagen. 2012. Published 2011 Wiley Periodicals, Inc. 相似文献
56.
Veruska Lima Moura Brasil Mariana Bitu Ramos Pinto Roberta Ferreti Bonan Luiz Paulo Kowalski Danyel Elias da Cruz Perez 《Journal of oral pathology & medicine》2018,47(7):641-651
Humans may be exposed to pesticides such as fungicides, herbicides, and insecticides, during occupational and non‐occupational activities. Pesticides could be related to cancer development mainly because of their effects on the endocrine and immune systems and their cumulative effect. The present review evaluated in current literature evidence of an association between exposure to pesticides and the occurrence of head and neck cancer (HNC). A literature search for cohort studies was conducted in the PubMed, Web of science, and Cochrane databases. Methodological quality of each study was rated with the Scottish Intercollegiate Guidelines Network (SIGN) checklist. One thousand one hundred and thirty‐two studies were identified. Thirty‐two were included. Most of the studies found addressed occupational exposure to pesticides and were conducted in Europe and North America. Eleven high‐quality studies were found. Most of them found no association between exposure to pesticides and increased risk of HNC. Two studies found some evidence of a positive association between pesticide (malathion and atrazine) exposure and thyroid cancer. The literature review does not support a clear evidence for association between pesticides exposure and HNC. Only limited evidence points to a positive association between exposure to some pesticides and thyroid cancer. Further standardized studies based on appropriate designs are required to clarify the effect of pesticides on the genesis of HNC, considering dose, length of exposure, and type of pesticide. 相似文献
57.
Catarina Patrício Mariana Marques Silva Pedro Eduardo Silva João Oliveira Luís Bagulho 《Revista portuguesa de cardiologia》2018,37(5):447.e1-447.e6
A 49-year-old woman was hospitalized for acute left foot arterial ischemia. Arterial Doppler revealed occlusion of the dorsalis pedis and posterior tibial arteries. A computed tomography angiography performed to assess abdominal pain showed hepatic, splenic, renal and pancreatic infarctions. A splenic artery embolism and a small aortic wall thrombus at the celiac trunk were identified. No radiological signs of aortic atherosclerosis were found. No predisposing conditions for secondary aortic thrombosis or intracardiac embolic sources were detected. It was determined that primary aortic thrombosis, a rare though potentially serious condition, was to blame. Isolated aortic mural thrombosis therapy is not well established, although systemic anticoagulation, thrombolysis, thromboaspiration, endovascular stent grafting and surgical thrombectomy have been attempted with varying success. In our patient, systemic anticoagulation therapy was initiated and resulted in aortic thrombus resolution. Close clinical follow-up is crucial, as the aortic thrombus can recur despite anticoagulation and aggressive control of the atherosclerotic risk factors. 相似文献
58.
Marina Dias-Neto Mariana Pintalhão Mariana Ferreira Nuno Lunet 《Nutrition and cancer》2013,65(2):133-147
The understanding of the association between salt intake and precancerous lesions may contribute to clarify the causal relation with gastric cancer. We systematically reviewed 17 articles addressing the association between dietary salt exposure and gastric intestinal metaplasia and conducted meta-analyses for quantitative synthesis (random effects model). Salt exposure was estimated assessing salted/salty food consumption, preference for salted/salty foods, use of table salt, or sodium urinary excretion. Heterogeneity was also large regarding food items evaluated, consumption categories, and data analysis. The combined odds ratio (OR) was 1.68 (95% confidence interval (CI) = 0.98–2.90; I2 = 55.4%) for the association between salted/salty meat and intestinal metaplasia (4 studies) and the OR was 1.53 (95% CI = 0.72–3.24; I2 = 76.8%) for salt preference. There was a positive, nonstatistically significant association between intestinal metaplasia and urinary sodium excretion. The heterogeneity of methodological options and results preclude quantitative synthesis or its proper interpretation, even if the available evidence may suggest a positive association between salt and intestinal metaplasia. 相似文献
59.
Lívia Alves Amaral Santos Talles Bazeia Lima Laís Augusti Letícia de Campos Franzoni Fabio da Silva Yamashiro Fernanda Bolfi Vânia dos Santos Nunes Mariana de Souza Dorna Cássio Vieira de Oliveira Carlos Antonio Caramori Giovanni Faria Silva Fernando Gomes Romeiro 《Journal of gastroenterology and hepatology》2016,31(1):229-234
60.
Masamichi Hayashi Nissim Silanikove Xiaofei Chang Rajani Ravi Vui Pham Gilson Baia Keren Paz Mariana Brait David Sidransky Wayne M Koch 《Cancer biology & therapy》2015,16(8):1184-1193
Triple negative breast cancer has an extremely poor prognosis when chemotherapy is no longer effective. To overcome drug resistance, novel drug delivery systems based on nanoparticles have had remarkable success. We produced a novel nanoparticle component ‘MDC’ from milk-derived colloid. In order to evaluate the anti-cancer effect of MDC, we conducted in vitro and in vivo experiments on cancer cell lines and a primary tumor derived breast xenograft. Doxorubicin (Dox) conjugated to MDC (MDC-Dox) showed higher cancer cell growth inhibition than MDC alone especially in cell lines with high EGFR expression. In a mouse melanoma model, MDC-Dox significantly suppressed tumor growth when compared with free Dox. Moreover, in a primary tumor derived breast xenograft, one of the mice treated with MDC-Dox showed partial regression, while mice treated with free Dox failed to show any suppression of tumor growth. We have shown that a novel nanoparticle compound made of simple milk-derived colloid has the capability for drug conjugation, and serves as a tumor-specific carrier of anti-cancer drugs. Further research on its safety and ability to carry various anti-cancer drugs into multiple drug-resistant primary breast models is warranted. 相似文献