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951.
Eneida Franco Vencio Alessandra Mota Carolina de Melo Pinho Aylton Alves Dias Filho 《Journal of oral pathology & medicine》2006,35(4):249-251
Odontogenic keratocyst is a cystic lesion characterized by a high rate of recurrence. This report describes a rare case of ciliated epithelium-lined odontogenic keratocyst in the maxilla of a 27-year-old female. Panoramic radiography showed a lytic lesion on the right maxilla associated with an impacted molar tooth. Computerized tomography image revealed the involvement of the lesion with the right maxillary sinus, destroying the sinus floor. Histopathologically, the typical keratinized epithelial-lined cyst of odontogenic keratocyst abruptly changed into a ciliated epithelium, suggesting the fusion of both these epithelia rather a metaplastic transformation. The biological behaviour of odontogenic keratocysts is discussed. 相似文献
952.
Exposure to light-at-night increases the growth of DMBA-induced mammary adenocarcinomas in rats 总被引:4,自引:0,他引:4
Cos S Mediavilla D Martínez-Campa C González A Alonso-González C Sánchez-Barceló EJ 《Cancer letters》2006,235(2):266-271
In order to assess whether light exposure at night influences the growth of mammary tumors, as well as the role of melatonin in this process, female rats bearing DMBA-induced mammary adenocarcinomas were exposed to different lighting environments. Animals exposed to light-at-night, especially those under a constant dim light during the darkness phase, showed: (a) significantly higher rates of tumor growth as well as lower survival than controls, (b) higher concentration of serum estradiol, and (c) lower nocturnal excretion of 6-sulfatoxymelatonin, without there being differences between nocturnal and diurnal levels. These results suggest that circadian and endocrine disruption induced by light pollution, could induce the growth of mammary tumors. 相似文献
953.
Long-term effectiveness against cholera of oral killed whole-cell vaccine produced in Vietnam 总被引:1,自引:0,他引:1
Thiem VD Deen JL von Seidlein L Canh do G Anh DD Park JK Ali M Danovaro-Holliday MC Son ND Hoa NT Holmgren J Clemens JD 《Vaccine》2006,24(20):4297-4303
We assessed the long-term protection afforded by a killed whole-cell oral cholera vaccine produced in Vietnam. A mass immunization of children and adults with the killed whole-cell oral cholera vaccine was undertaken in half of the communes of Hue, Vietnam, in 1998; the remaining communes were immunized in 2000. No cholera was observed in Hue until 2003, when an outbreak of El Tor cholera made it possible to conduct a case-control study. The overall vaccine effectiveness 3-5 years after vaccination was 50% (9-63%). This low-cost, easily administered vaccine should be considered as a tool for the control of cholera. 相似文献
954.
955.
Ceramide is a mediator of apoptosis in retina photoreceptors 总被引:5,自引:0,他引:5
German OL Miranda GE Abrahan CE Rotstein NP 《Investigative ophthalmology & visual science》2006,47(4):1658-1668
PURPOSE: The precise mechanisms involved in photoreceptor apoptosis are still unclear. In the present study, the role of ceramide, a sphingolipid precursor that induces apoptosis on cellular stress, was investigated in relation to the activation of cell death in photoreceptors. METHODS: Rat retina neuronal cultures, with or without docosahexaenoic acid (DHA), were treated with the ceramide analogue acetylsphingosine (C2-ceramide), and with a glucosylceramide synthase inhibitor. Ceramide synthesis in cultures treated with the oxidant paraquat was evaluated with [3H]palmitate. The effect of inhibitors of ceramide de novo synthesis, fumonisin B1 and cycloserine, on photoreceptor apoptosis was investigated. Apoptosis, mitochondrial membrane potential, and Bcl-2 expression were determined. RESULTS: Addition of C2-ceramide induced photoreceptor apoptosis. Paraquat increased formation of [3H]ceramide in photoreceptors, compared with the control, whereas inhibition of ceramide synthesis, immediately before paraquat treatment, prevented paraquat-induced photoreceptor apoptosis. Fumonisin also reduced photoreceptor apoptosis during early development in vitro. DHA, the retina major polyunsaturated fatty acid, which protects photoreceptors from oxidative stress-induced apoptosis, completely blocked C2-ceramide-induced photoreceptor death, simultaneously increasing Bcl-2 expression. Inhibiting glucosylceramide synthase, which catalyzes ceramide glucosylation, before ceramide or paraquat treatment blocked DHA's protective effect. CONCLUSIONS: The results suggest that oxidative stress stimulated an increase in ceramide levels that induced photoreceptor apoptosis. DHA prevented oxidative stress and ceramide damage by upregulating Bcl-2 expression and glucosylating ceramide, thus decreasing its intracellular concentration. This shows for the first time that ceramide is a critical mediator for triggering photoreceptor apoptosis in mammalian retina and suggests that modulating ceramide levels may provide a therapeutic tool for preventing photoreceptor death in neurodegenerative diseases. 相似文献
956.
Cos S González A Güezmes A Mediavilla MD Martínez-Campa C Alonso-González C Sánchez-Barceló EJ 《International journal of cancer. Journal international du cancer》2006,118(2):274-278
Melatonin inhibits the growth of breast cancer cells by interacting with estrogen-responsive pathways, thus behaving as an antiestrogenic hormone. Recently, we described that melatonin reduces aromatase expression and activity in MCF-7 human breast cancer cells, thus modulating the local estrogen biosynthesis. To investigate the in vivo aromatase-inhibitory properties of melatonin in our current study, this indoleamine was administered to rats bearing DMBA-induced mammary tumors, ovariectomized (ovx) and treated with testosterone. In these castrated animals, the growth of the estrogen-sensitive mammary tumors depends on the local aromatization of testosterone to estrogens. Ovariectomy significantly reduced the size of the tumors while the administration of testosterone to ovx animals stimulated tumor growth, an effect that was suppressed by administration of melatonin or the aromatase inhibitor aminoglutethimide. Uterine weight of ovx rats, which depends on the local synthesis of estrogens, was increased by testosterone, except in those animals that were also treated with melatonin or aminoglutethimide. The growth-stimulatory effects of testosterone on the uterus and tumors depend exclusively on locally formed estrogens, since no changes in serum estradiol were appreciated in testosterone-treated rats. Tumors from animals treated with melatonin had lower microsomal aromatase activity than tumors of animals from other groups, and incubation with melatonin decreased the aromatase activity of microsomal fractions of tumors. Animals treated with melatonin had the same survival probability as the castrated animals and significantly higher survival probability than the uncastrated. We conclude that melatonin could exert its antitumoral effects on hormone-dependent mammary tumors by inhibiting the aromatase activity of the tumoral tissue. 相似文献
957.
Incidence of BRCA1 and BRCA2 mutations in 54 Chilean families
with breast/ovarian cancer, genotype–phenotype correlations 总被引:4,自引:0,他引:4
Gallardo M Silva A Rubio L Alvarez C Torrealba C Salinas M Tapia T Faundez P Palma L Riccio ME Paredes H Rodriguez M Cruz A Rousseau C King MC Camus M Alvarez M Carvallo P 《Breast cancer research and treatment》2006,95(1):81-87
Summary Our aim was to analyze the incidence of mutations in BRCA1 and BRCA2 genes in 54 families with breast/ovarian cancer. Families
were selected from three Institutions following the standard criteria for hereditary breast/ovarian cancer. PCR amplification
of all exons was performed, followed by SSCP, heteroduplex, PTT and sequencing analysis. We identified eight truncation mutations,
three in the BRCA1 gene and five in the BRCA2 gene. Three of these mutations have not been reported previously by other groups:
308insA in one family, 3936 C>T in two families, for BRCA1, and 4970insTG in one family for BRCA2. In addition two families
having Ashkenazi Jewish ancestors present the well known mutations 185delAG and 6174delT. Interestingly, 5 out of 11 families
have mutations recurrent in Spanish families. Among the 54 families selected, seven have breast and ovary cancer cases, and
only two presented a mutation in BRCA1 or BRCA2 genes. Other cancers as prostate and stomach are frequent among relatives
carrying the mutation. Five cases of very early onset (<31 years old) breast cancer were detected. The frequencies of BRCA1
(0.074) and BRCA2 (0.13) mutations in our families is low but similar to the incidence found in other populations, like in
Spain. Since is widely known that risk factors that modulate the development of breast cancer such as lifestyle risk factors,
geographic location, country of origin and socioeconomic status, besides a familial history of breast cancer our findings
suggest that the history of colonization and immigrations is very relevant when studying hereditary factors associated to
breast cancer. 相似文献
958.
Herrera C Agoff C 《Cadernos de saúde pública / Ministério da Saúde, Funda??o Oswaldo Cruz, Escola Nacional de Saúde Pública》2006,22(11):2349-2357
This qualitative study of 30 physicians and nurses from the Mexican public health system aimed to understand their concepts and practices concerning domestic violence. A recent survey showed that most health professionals were unaware of the official criteria and procedures for dealing with cases of domestic violence. Our in-depth interviews failed to show substantial differences between professionals according to level of care, and that treatment was generally inadequate. We also observed a repertoire of ingrained social meanings among the medical staff concerning violence (derived from their own cultural traditions), hindering more effective responses to the problem. 相似文献
959.
This qualitative study aims at identifying which mechanisms are used by elderly patients to express pain when they are not able to use verbal communication. It relies on the accounts and interpretations of 6 nurses working in a clinical service unit dedicated to the treatment of the elderly at a hospital in S?o Paulo. Data were collected through semi-structured interviews, recorded and transcribed for hermeneutic analysis. Data were grouped together in selected analytical categories related to pain and communication, which showed that nurses' interactions with patients notice attitudes and changes. The prompt interpretation and identification of these cues and symptoms of pain lead to better nursing care. 相似文献
960.
OBJECTIVE: Of the effects of air pollution on children's health, increased pneumonia admission rate is one of the most important. The study aimed at estimating the association between pneumonia admissions and increased air pollutants. METHODS: An ecological time-series study was carried out in the municipality of S?o José dos Campos, Southeastern Brazil, in the years 2000 and 2001. Daily records of pneumonia admissions, air pollutants (SO2, O3, and PM10) and weather conditions (temperature and humidity) were analyzed. The correlations between the study variables were estimated using Pearson's correlation. The associations between pneumonia and air pollutants were estimated using generalized additive Poisson regression models. The percentage increase (and their respective 95% CI) in pneumonia admission rate was estimated for the interquartile range of each air pollutant studied. RESULTS: The three pollutants analyzed presented lagged effects on pneumonia admission rate, beginning at lag 3 or 4 and lasting for no more than two days. The 8-day cumulative effect estimate showed that an increase of 24.7 mg/m3 in PM10 concentration increased pneumonia admission rate in 9.8%. CONCLUSIONS: The study corroborates that adverse health effects of air pollutants can be observed even in medium-sized cities. The magnitude of the effect was similar to that found in the city of S?o Paulo. Moreover, children are highly susceptible to air pollution exposure. 相似文献