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391.
Computer-assisted analysis of p53 and PCNA expression in oral lesions infected with human papillomavirus 总被引:1,自引:0,他引:1
Soares CP Benatti Neto C Fregonezi PA Teresa DB Santos RT Longatto Filho A Maeda MY 《Analytical and quantitative cytology and histology / the International Academy of Cytology [and] American Society of Cytology》2003,25(1):19-24
OBJECTIVE: To carry out a retrospective study to determine whether human papillomavirus (HPV) infection and immunohistochemical expression of p53 and proliferating cell nuclear antigen (PCNA) are related to the risk of oral cancer. STUDY DESIGN: Fifty-seven oral biopsies, consisting of 30 oral squamous papillomas (OSPs) and 27 oral squamous cell carcinomas (OSCCs) were tested for the presence of HPV 6/11 and 16/18 by in situ hybridization using catalyzed signal amplification and in situ hybridization. p53 And PCNA expression was analyzed by immunohistochemistry and evaluated quantitatively by image analysis. RESULTS: Nineteen of the 57 oral lesions (33.3%) were positive for HPV. HPV 6/11 was found in 6 of 30 (20%) OSPs and 1 of 27 (3.7%) OSCCs. HPV 16/18 was found in 10 of 27 (37%) OSCCs and 2 of 30 (6.7%) OSPs. Sixteen of the 19 HPV-positive cases (84.2%) were p53 negative; 5 (9%) were HPV 6/11 and 11 (19%) HPV 16/18, with an inverse correlation between the presence of HPV DNA and p53 expression (P = .017, P < .05). PCNA expression appeared in 18 (94.7%) of HPV positive cases, showing that HPV 16/18 was associated with intensity of PCNA expression and with OSCCs (P = .037, P < .05). CONCLUSION: Quantitative evaluation of p53 by image analysis showed an inverse correlation between p53 expression and HPV presence, suggesting protein degradation. Image analysis also demonstrated that PCNA expression was more intense in HPV DNA 16/18 OSCCs. These findings suggest involvement of high-risk HPV types in oral carcinogenesis. 相似文献
392.
Padoan Junior AC De A Barreto G Araújo AF 《International journal of neural systems》2003,13(2):119-127
In this paper we proposed an unsupervised neural architecture, called Temporal Parametrized Self Organizing Map (TEPSOM), capable of learning and reproducing complex robot trajectories and interpolating new states between the learned ones. The TEPSOM combines the Self-Organizing NARX (SONARX) network, responsible for coding the temporal associations of the robotic trajectory, with the Parametrized Self-Organizing (PSOM) network, responsible for an efficient interpolation mechanism acting on the SONARX neurons. The TEPSOM network is used to model the inverse kinematics of the PUMA 560 robot during the execution of trajectories with repeated states. Simulation results show that the TEPSOM is more accurate than the SONARX in the reproduction of the learned trajectories. 相似文献
393.
Bruggink C Wuhrer M Koeleman CA Barreto V Liu Y Pohl C Ingendoh A Hokke CH Deelder AM 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2005,829(1-2):136-143
A capillary-scale high-pH anion-exchange chromatography (HPAEC) system for the analysis of carbohydrates was developed, in combination with two parallel on-line detection methods of sub-picomolar sensitivity: (1) pulsed amperometric detection (PAD); (2) capillary-scale desalting followed by electrospray ion-trap (IT) mass spectrometry (MS). The capillary chromatographic system combined the superb selectivity of HPAEC that allows routine separation of isomeric oligosaccharides with the information on monosaccharide sequence and linkage positions obtained by MS/MS fragmentation using the IT-MS. The applicability of the system in biomedical research was demonstrated by its use for the analysis of a urine sample of a GM1-gangliosidosis patient. Isomeric glycans in the sample could be resolved by HPAEC and assigned on the basis of the monosaccharide linkage information revealed by on-line IT-MS/MS. 相似文献
394.
Adult specimens of Cochliomyia macellaria, Chrysomya megacephala, Ch. rufifacies, Lucilia sp. (Calliphoridae), Musca domestica (Muscidae), Oxelytrum discicolle (Silphidae) and Sarcophagidae were recovered from 12 human cadavers in Cali, Valle, Colombia. Information regarding these findings is presented. 相似文献
395.
Maria Beatriz De Barros‐Barreto Lynne McIvor Christine A. Maggs Paulo Cavalcanti Gomes Ferreira 《Journal of phycology》2006,42(4):905-921
Morphological investigations identified 11 Ceramium Roth species, of the 18 previously reported from Brazil. Phylogenetic analyses of sequences of the chloroplast‐encoded rbcL gene confirmed the presence of seven of these species. Three other species are reported from Brazil for the first time. Ceramium affine Setchell & Gardner and C. filicula Harvey ex Womersley were previously known only from the Pacific Ocean (Mexico and Australia, respectively). A new species, C. fujianum Barros‐Barreto et Maggs sp. nov., is described here. Its general habit is similar to that of C. strictum sensu Harvey from Europe but it has one less periaxial cell than C. strictum; its cortical filament arrangement is closest to C. deslongchampsii Chauvin ex Duby, also from Europe, but whorled tetrasporangia partially covered by cortical cells differ strikingly from the naked protruding tetrasporangia of C. deslongchampsii. Ceramium species in which each periaxial cell cuts off transversely only a single basipetal cell formed a robust clade. The genus Ceramium as represented in Brazil is not monophyletic with respect to Centroceras Kützing and Corallophila Weber‐van Bosse; Ceramium nitens, which has axial cells completely covered by rounded cortical cells formed by acropetal and basipetal filaments, did not group with any Ceramium clade but was weakly allied to a species of Corallophila. All three Brazilian Centroceras sequences were attributed to a single species, C. clavulatum. 相似文献
396.
Rats turned diabetic by treatment with alloxan exhibit a significant reduction in serosal mast cell numbersin parallel with decreased insulin levels in the plasma. Our aim was to investigate the putative involvement of endogenous glucocorticoid hormone in this phenomenon. The findings indicated that rats treated with alloxan responded with an increase in levels of serum corticosterone concomitantly with decreased mast cell numbers in the pleural space. We found that either surgical bilateral adrenalectomy or pretreatment with the steroid antagonist RU 486 (20 mg/kg, i.p.) impaired the drop in pleural mast cell counts in alloxinated rats. Administration of insulin (15 U/kg) prevented the increase in corticosterone levels and restored pleural mast cell levels in diabetic animals. In addition, treatment of naive rats with corticosterone (0.5 mg/kg, s.c.) or dexamethasone (0.1 mg/kg, s.c.), for 3 consecutive days, led to a reduction in the number of mast cells recovered from the pleural cavity as noted in diabetic animals. In contrast, insulin reduced serum corticosterone levels and induced a significant elevation in pleural mast cell numbers in naive rats. We conclude that there is a causative relationship between increased levels of glucocorticoids and down-regulation of mast cell numbers associated with the diabetic state, both phenomena clearly sensitive to insulin. 相似文献
397.
Denise Wohlmeister Débora Renz Barreto Vianna Virgínia Etges Helfer Fabrícia Gimenes Marcia Edilaine Lopes Consolaro Regina Bones Barcellos Maria Lucia Rossetti Luciane Noal Calil Andréia Buffon Diogo André Pilger 《Memórias do Instituto Oswaldo Cruz》2016,111(2):106-113
The influence of different infectious agents and their association with human
papillomavirus (HPV) in cervical carcinogenesis have not been completely elucidated.
This study describes the association between cytological changes in cervical
epithelium and the detection of the most relevant aetiological agents of sexually
transmitted diseases. Samples collected from 169 patients were evaluated by
conventional cytology followed by molecular analysis to detect HPV DNA,
Chlamydia trachomatis, herpes simplex virus 1 and
2,Neisseria gonorrhoeae, Mycoplasma genitalium,
Trichomonas vaginalis, andTreponema pallidum,
besides genotyping for most common high-risk HPV. An association between cytological
lesions and different behavioural habits such as smoking and sedentariness was
observed. Intraepithelial lesions were also associated with HPV and C.
trachomatis detection. An association was also found between both simple
and multiple genotype infection and cytological changes. The investigation of HPV and
C. trachomatisproved its importance and may be considered in the
future for including in screening programs, since these factors are linked to the
early diagnosis of patients with precursor lesions of cervical cancer. 相似文献
398.
Heitor G. Araújo-Filho Lucindo J. Quintans-Júnior André S. Barreto Jackson R. G. S. Almeida Rosana S. S. Barreto Jullyana S. S. Quintans 《Neurochemical research》2016,41(4):647-658
Peripheral nerve injury (PNI) is a serious public health problem that is linked with motor, sensory and autonomic deficits. Given the fact that this type of disorder leads to a decreased quality of life in most patients and adherence of available drugs is limited and have adverse effects, we investigated the efficacy of natural products in a PNI model. The search terms plants, medicinal, nerve regeneration, nerve crush, sciatic nerve as well as MeSH terms or free-text words were used to retrieve English language articles in PubMed, Scopus, Web of Science and LILACS published until July 2015. After sciatic nerve crush, natural products have improved significantly motor performance, sensory function and electrical conductance measured over weeks. Among the pharmacological targets suggested by the action of natural products, there were citations on the activation of the antiapoptotic signaling pathway, modulation in the expression of pro-inflammatory cytokines and neurotrophic factors. The systematic review provides scientific evidence that natural products are pharmacologically effective in the treatment of PNI such as sciatic nerve crush. 相似文献
399.