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111.
The air in Santiago, Chile, is among the most highly polluted in the world. Due to the high levels of pollutants and the high incidence of respiratory diseases, especially in the most susceptible groups, Santiago has been declared a saturated zone for PM10, O3, and CO. The aim of this work was to investigate polycyclic aromatic hydrocarbon levels and mutagenic activity of Santiago's fine and coarse fractions of inhalable particles. The levels of 16 polycyclic aromatic hydrocarbons (PAHs) were determined by highperformance liquid chromatography in organic extracts from respirable particles (OERP). Respirable particulate matter (fine and coarse) contains high levels of PAHs including six mutagenic ones classified by the IARC as carcinogenic, which represented at least 45% of the total PAH concentration. A seasonal effect was observed, with higher values in months with lower temperatures. Although a significant decline of PAH levels in OERP was observed in the last years, the levels of carcinogenic PAHs are still higher than those reported in cities of the United States, Australia, and Europe. OERP were highly mutagenic and contained direct and indirect mutagens, which produced both frameshift and base substitution mutations in Salmonella typhimurium. In addition, organic extracts from total suspended particles were also highly mutagenic at the tk locus in h1A1v2 human lymphoblasts in culture. In spite of the important decrease in PAHs in the period 1991–1996, direct mutagenic response has not changed significantly, suggesting that the levels of direct mutagenic pollutants (e.g., nitroarenes) have not decreased considerably during the last years. These results suggest a risk for Santiago's inhabitants since pollutants adsorbed in inhalable particles are highly mutagenic and can damage DNA. 相似文献
112.
Silvia Goñi Esarte Antonio Arín Letamendía Juan José Vila Costas Francisco Javier Jiménez Pérez David Ruiz-Clavijo García Juan Carrascosa Gil María Luz Almendral López 《Gastroenterologia y hepatologia》2013
Esophageal lichen planus (ELP) is a rare condition with unknown prevalence that can sometimes be underestimated due to the subtle and nonspecific findings of diagnostic workup. Oral lesions rarely extend to the esophageal mucosa, but when they do, the most frequent symptoms are dysphagia and odynophagia. There is often a significant delay in diagnosis and inadequate treatment. We report the case of a 59-year-old woman diagnosed with ELP, successfully treated with rituximab, a chimeric monoclonal antibody that depletes CD20+B cells. To our knowledge, this is only the second report of this treatment in ELP. 相似文献
113.
Significance of COX‐2 and VEGF expression in histopathologic grading and invasiveness of meningiomas
Sung Hak Lee Youn Soo Lee Yong Gil Hong Chang Suk Kang 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2014,122(1):16-24
Meningiomas are slow‐growing neoplasms that recur locally. Their morphologic grading does not always correlate with patient outcome. We evaluated the status of several immunohistochemical markers with histopathologic parameters in various grades of meningioma.Eighty‐eight meningioma specimens were examined immunohistochemically to determine the status of Ki‐67, cyclin D1, epidermal growth factor receptor (EGFR), cyclooxygenase‐2 (COX‐2), vascular endothelial growth factor (VEGF), and bcl‐2. Several clinical and pathological parameters were investigated.Forty‐nine Grade I, 33 Grade II, and 6 Grade III meningiomas were observed. VEGF and Ki‐67 expression was correlated with higher tumor grade. The association between grade and other immunohistochemical markers expression was not significant. A correlation was observed between COX‐2 expression and invasiveness to the brain or adjacent soft tissue. Tumor recurrence was correlated with brain or adjacent soft tissue invasion. We also observed a relationship between VEGF level and COX‐2 expression, and they were both correlated with necrosis.Immunohistochemical evaluation of VEGF, COX‐2, and Ki‐67 expression can provide information regarding the behavior of meningiomas, particularly for cases in which histological grading is not straightforward. 相似文献
114.
B. Ruiz Torres C. Ramos Paesa T. Rivero Salvador C. Marín Zaldívar D. Gil Pérez 《Revista espa?ola de anestesiología y reanimación》2021,68(6):357-360
Septic meningitis secondary to epidural anesthesia is a rare but serious complication that is usually related to exogenous contamination from inadequate aseptic techniques, so the most frequent microorganisms observed are S. aureus and S. salivarius. We describe the case of a woman who, after receiving epidural anesthesia for normal delivery, presented septic meningitis due to E. faecium with recurrence after antibiotic treatment, probably secondary to pyogenic ventriculitis undetected in the first episode.We highlight the rarity of the case, emphasizing the need for strict aseptic technique, and review the literature on the most appropriate treatment for this type of complication. 相似文献
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Tey HL Maddison B Wang H Ishiju Y McMichael A Marks M Willford P Maruzivab D Ferdinando D Dick J Yosipovitch G 《Acta dermato-venereologica》2012,92(5):529-531
Abstract is missing (Letter). 相似文献
119.