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51.
Photochemical products in urban mixtures enhance inflammatory responses in lung cells 总被引:1,自引:0,他引:1
Sexton KG Jeffries HE Jang M Kamens RM Doyle M Voicu I Jaspers I 《Inhalation toxicology》2004,16(Z1):107-114
Complex urban air mixtures that realistically mimic urban smog can be generated for investigating adverse health effects. "Smog chambers" have been used for over 30 yr to conduct experiments for developing and testing photochemical models that predict ambient ozone (O(3)) concentrations and aerosol chemistry. These chambers were used to generate photochemical and nonirradiated systems, which were interfaced with an in vitro exposure system to compare the inflammatory effects of complex air pollutant mixtures with and without sunlight-driven chemistry. These are preliminary experiments in a new project to study the health effects of particulate matter and associated gaseous copollutants. Briefly, two matched outdoor chambers capable of using real sunlight were utilized to generate two test atmospheres for simultaneous exposures to cultured lung cells. One chamber was used to produce a photochemically active system, which ran from sunrise to sunset, producing O(3) and the associated secondary products. A few hours after sunset, NO was added to titrate and remove completely the O(3), forming NO(2). In the second chamber, an equal amount of NO(2) and the same amount of the 55-component hydrocarbon mixture used to setup the photochemical system in the first side were injected. A549 cells, from an alveolar type II-like cell line grown on membranous support, were exposed to the photochemical mixture or the "original" NO(2)/hydrocarbon mixture for 5 h and analyzed for inflammatory response (IL-8 mRNA levels) 4 h postexposure. In addition, a variation of this experiment was conducted to compare the photochemical system producing O(3) and NO(2), with a simple mixture of only the O(3) and NO(2). Our data suggest that the photochemically altered mixtures that produced secondary products induced about two- to threefold more IL-8 mRNA than the mixture of NO(2) and hydrocarbons or O(3). These results indicate that secondary products generated through the photochemical reactions of NO(x) and hydrocarbons may significantly contribute to the inflammatory responses induced by exposure to urban smog. From previous experience with relevant experiments, we know that many of these gaseous organic products would contribute to the formation of significant secondary organic particle mass in the presence of seed particles (including road dust or combustion products). In the absence of such particles, these gaseous products remained mostly as gases. These experiments show that photochemically produced gaseous products do influence the toxic responses of the cells in the absence of particles. 相似文献
52.
Macovei GN Varlam H St Antohe D 《Revista medico-chirurgical?? a Societ????ii de Medici ??i Naturali??ti din Ia??i》2002,106(4):757-761
Tele-encephalization process is accompanied by the appearance and progressive complication of the middle cerebral artery system. The aim of our study is to analyze the morphometrical parameters of the middle cerebral artery branches in the beginning of the edification of its system. We used 162 cerebral hemispheres from 88 fetuses aged of 13-15 weeks. Middle cerebral artery system was injected with a gelatin-China ink mixture and images recorded by means of a Zeiss surgical microscope. Parameters evaluation (length, proximal and distal diameters, external surface, volume, angles of bifurcation) was realized with KS-300 program. At this early age middle cerebral artery system has only 4-5 generations of branches usually resulting from acute angle bifurcations. 相似文献
53.
Di Napoli Alberto Tagliente Emanuela Pasquini Luca Cipriano Enrica Pietrantonio Filomena Ortis Piermaria Curti Simona Boellis Alessandro Stefanini Teseo Bernardini Antonio Angeletti Chiara Ranieri Sofia Chiatamone Franchi Paola Voicu Ioan Paul Capotondi Carlo Napolitano Antonio 《Journal of digital imaging》2023,36(2):603-616
Journal of Digital Imaging - Chest CT is a useful initial exam in patients with coronavirus disease 2019 (COVID-19) for assessing lung damage. AI-powered predictive models could be useful to better... 相似文献
54.
Botez C Iliescu ML Zanoschi G Manole BM Olteanu S 《Revista medico-chirurgical?? a Societ????ii de Medici ??i Naturali??ti din Ia??i》2005,109(2):392-396
Providing secondary health care for military staff and related personnel, Clinical Emergency Military Hospital "Dr. Iacob Cihac" it is the biggest hospital among those having the same profile. There are many factors with influence upon hospital's activities. Some factors can be measured (number of beds, the prevalence of a certain disease in population), but also some of them are subjective, creating pressures in hospitals utilization (costs, status of the professionals and hospital, desires of patients and their families). Good statistical information about hospitalized morbidity provides the basis for planning, control and efficient administration and can also serve as an input into the development of more effective preventive health strategies. There are some important differences between public own hospital and military hospital: for public hospitals, the main cause of morbidity is represented of respiratory disease, while for the military hospital on the top are nervous and psychiatric diseases; also, it is different the proportion of inpatients according to age groups - for public hospitals the main proportion of inpatients is aged more than 45-60 years old, but for the military hospital there are also well represented those aged under 29 years old. The differences between the average length of stay in hospitals is due to hospitalization of psychiatric diseases in public hospitals. 相似文献
55.
Brumboiu I Gocan G Bocşan IS Soşa I Sava A Ursu L Olariu O Paştină I Simionca L 《Revista medico-chirurgical?? a Societ????ii de Medici ??i Naturali??ti din Ia??i》2005,109(3):616-622
The most objective analysis of measles herd immunity could be made by sero-epidemiological study. In the population of North-West area of Romania we have evaluated the measles immune protection through a seroprevalence study, using an age stratified sample of population in witch the subjects from Cluj and Bistri?a-N?s?ud counties were voluntarily involved. The measles antibody concentration was determined by immunoassay method using Hycor test. The database was performed in Microsoft Access and the statistics in Epi Info 2000. Levels higher then 40 arbitrary units (the cut-off of protection) of the measles antibody were met in 80% (IC95% : 75.09-84.01) of all subjects, 82.4% of the females and 84.9% of the urban area peoples. 98.3% of all subjects had detectable antibody levels. The protection increased by age: the adults had protective levels in at least 90% of cases. Global vaccine efficacy was 64.7% (IC95 % : 56.5 - 72.9), moderately decreasing with increasing age (the correlation coefficient--58.1%). In the assessed sample, the measles protection was the highest in adults, women and subjects from urban areas. The vaccine efficacy was relatively small, but the majority of subjects had detectable titers of measles antibody. 相似文献
56.
57.
Ruslan Damadzic Shanop Shuangshoti Georgeta Giblen Mary M. Herman 《European archives of psychiatry and clinical neuroscience》2003,253(6):338-339
CONTENTS OF VOLUME 253 (2003)
Contents of volume 253 (2003) 相似文献58.
Spectrum of MRI appearances of untreated metastases of the liver 总被引:3,自引:0,他引:3
Danet IM Semelka RC Leonardou P Braga L Vaidean G Woosley JT Kanematsu M 《AJR. American journal of roentgenology》2003,181(3):809-817
OBJECTIVE: The purpose of our study was to identify the spectrum of MRI appearances of untreated liver metastases from different primary origins. MATERIALS AND METHODS: Over a period of 52 months, we used our clinical information system to retrospectively identify the first MRIs obtained in 165 consecutive patients who had untreated liver metastases. All patients had histologic confirmation of the primary tumor. Liver metastases were confirmed at histologic examination, on imaging, or at clinical follow-up. MR sequences used included T1-weighted spoiled gradient-echo, T2-weighted half-Fourier acquisition single-shot turbo spin-echo, and serial gadolinium-enhanced spoiled gradient-echo imaging. Size, signal intensity characteristics, and pattern of enhancement of the metastases on MRIs were evaluated by two radiologists in consensus. Lesions were categorized by size: smaller than 1.5 cm, between 1.5 and 3.0 cm, and larger than 3.0 cm. RESULTS: A total of 516 metastases (size range, 5-120 mm; mean, 28 mm) were assessed. Fifty-nine patients had hypervascular lesions, and 106 patients had hypovascular lesions. A significant difference in proportion of tumor vascularity was observed between the primary tumors described as classically hypervascular and those described as classically hypovascular (chi-square test for proportions of 70.8, p < 0.0001). The most common pattern was peripheral ring (72% of patients) seen on the arterial dominant phase images, with incomplete central progression (63%) seen on the delayed phase images. A hypointense ring seen in the periphery of the tumor during the delayed phase was the most common appearance in hypervascular metastases (27% patients) and was particularly conspicuous in patients with neuroendocrine and carcinoid tumors. Perilesional enhancement was common (47%), mostly seen in hypovascular metastases (92%). Generally, large lesions tended to show a peripheral ring or heterogeneous enhancement, and small lesions showed homogeneous enhancement. CONCLUSION: MRI allows the identification of a wide spectrum of appearances of untreated liver metastases. The extent and pattern of enhancement of various histologic types of tumor are depicted on MRI. 相似文献
59.
Pascu ML Danaila L Voicu L Staicu A Truica S Ion RM 《Oftalmologia (Bucharest, Romania : 1990)》2003,57(2):73-80
The photodynamic therapy (PDT) became more and more widely used in the treatment of different malignant tumors. For present studies, porphyrins and haematoporphyrin derivatives, in the conditions of N2 laser radiation, were chosen because their strong absorption along a large spectral range; this makes possible the excitation of their fluorescence at 337.1 nm, which is the wavelength of the N2 pulsed laser radiation. The photophysical and photochemical properties depend on the central metal and the peripheral substituents. Trying to find an optimal sensitizer to be used with N2 laser in photodynamic therapy (PDT), a spectroscopic study of these dyes was performed. The obtained data show that the UV radiation emitted by a N2 pulsed laser may be used for PDT application; among other dyes having interesting characteristics, Zn-TSPP and Zn-TNP in DMSO at 0.5% concentration seem to be more relevant. 相似文献
60.
Anal carcinoma is rare; fistula-in-ano is sometimes mentioned among other premalignant conditions. Chronic anal fistula is associated with malignant transformation to mucinous adenocarcinoma, difficult to diagnose in the anal region and associated to a poor prognosis. Malignant transformation to infiltrating colloid carcinoma was surprised during a one year period, in a patient with long-standing perianal fistula (24 years). Inflammatory changes of the perineal region and other peculiar characteristics (such as neoplastic spread following supurative pathways) were responsible for diagnostic and surgical difficulties. 相似文献