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961.
962.
963.
Differential proteomic serum pattern of low molecular weight proteins expressed by adenocarcinoma lung cancer patients 总被引:4,自引:0,他引:4
Maciel CM Junqueira M Paschoal ME Kawamura MT Duarte RL Carvalho Mda G Domont GB 《Journal of experimental therapeutics & oncology》2005,5(1):31-38
Based on the assumption that proteins can emanate from tumour to serum, we investigated whether serum low molecular weight proteins (LMW) can discriminate lung cancer patients from healthy donors. Pooled sera from 20 lung cancer patients matched in sex (men), histological type (adenocarcinoma) and stage (IIIB and IV) and from 20 healthy donors (men) were submitted to 2-DE coupled to MALDI-TOF peptide mass fingerprinting. Results of 2D-E/ MALDI-TOF showed five up regulated proteins (immunoglobulin lambda chain, transthyretin monomer, haptoglobin-alfa 2 and two isoforms of serum amyloid protein) and one down regulated (fragment of apolipoprotein A-I) in patients. All differentially expressed proteins, except immunoglobulin, may be acting as a non-specific sign of inflammation in cancer and transthyretin monomer may act as a possible blood marker to CSF barrier disruption that occurs, e.g., in cerebral metastasis. In conclusion, this work shows the usefulness of 2D-gel electrophoresis and mass spectrometry proteomic techniques for the identification of up- and down-regulated proteins in serum from adenocarcinoma lung cancer patients. 相似文献
964.
Overexpression of platelet-derived growth factor receptor α in breast cancer is associated with tumour progression
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Introduction
Receptor tyrosine kinases have been extensively studied owing to their frequently abnormal activation in the development and progression of human cancers. Platelet-derived growth factor receptors (PDGFRs) are receptors with intrinsic tyrosine kinase activity that regulate several functions in normal cells and are widely expressed in a variety of malignancies. After the demonstration that gastrointestinal stromal tumours without c-Kit mutations harbour PDGFR-α-activating mutations and that PDGFR-α is also a therapeutic target for imatinib mesylate, the interest for this receptor has increased considerably. Because breast cancer is one of the most frequent neoplasias in women worldwide, and only one study has reported PDGFR-α expression in breast carcinomas, the aim of this work was to investigate the potential significance of PDGFR-α expression in invasive mammary carcinomas. 相似文献965.
Garcez FR Garcez WS Martins M Matos MF Guterres ZR Mantovani MS Misu CK Nakashita ST 《Planta medica》2005,71(10):923-927
The ethanolic extracts from the roots, the underground trunk and the leaves of Aiouea trinervis were active in the brine shrimp (Artemia salina) lethality assay (LD (50): 1.93, 0.92 and 262.1 microg/mL, respectively). Fractionation of the extracts led to the isolation of four butanolides, namely (-)-epilitsenolides C (2) and C (1) ( 1 and 2), isoobtusilactone A ( 3) and obtusilactone A ( 4), two of which ( 1 and 2) are reported for the first time as genuine natural products. The lignans (+)-sesamin ( 5) and (+)-methylpiperitol ( 6) and polyprenol-12 ( 7) were isolated as well. Their structures were determined with spectral methods (1D-, 2D-NMR and MS). Compounds 1, 2, 3, 5 and 6 were tested for their cytotoxic activities in Hep (2) human cancer cells. The butanolides 2 and 3 were the most active (IC (50): 5.96 microg/mL and 4.95 microg/mL, respectively) whereas the other compounds showed moderate IC (50) values ranging from 12.20 microg/mL to 25.64 microg/mL. The genotoxic properties of the crude ethanolic extracts and of compounds 3 and 5 were also evaluated in this study on CHO K1 and HTC mammalian cells with single-cell gel electrophoresis (comet assay). The crude extracts as well as the compounds tested induced DNA migration in this assay, which was indicative of DNA damage (genotoxic effect). 相似文献
966.
Emergency Units frequently assist suicide attempts. It is important to study this phenomenon in adolescence, since this is a conflict period. This study aimed to outline an epidemiological profile of adolescents admitted in an Emergency Unit, who were diagnosed as suicide attempters. Thus, we examined the records of adolescents admitted at this Unit as suicide attempters in 2002. The results revealed that 77.8% of the cases are characterized as follows: female, predominant age range between 15 and 19 years old, single, white, student, living in neighborhoods with low purchasing power, taking medication during the day. Our findings were similar to those described in other studies and thus require special attention. 相似文献
967.
Massafera R da Silva AM de Carvalho AP dos Santos DR Galati EA Teodoro U 《Revista de saúde pública》2005,39(4):571-577
OBJECTIVE: To identify the sandfly fauna and some aspects of their behavior in forest and anthropic environments. METHODS: Sandfly captures were undertaken in farm (23 degrees 6' S; 50 degrees 22' W), in Southern Brazil. Falc?o light traps were set in forest, domicile and domestic animal shelters and mosquitoes were collected monthly, between 17h and 7h, from March 1997 to February 1998. RESULTS: A total of 3,655 specimens representing 13 species were captured. Nyssomyia whitmani and Nyssomyia neivai were the predominant species, with a total of 2,977 specimens (81.0%). Of these two species, a total of 2,552 (85.7%) specimens were captured in intradomiciliary and peridomiciliary environments, 2,332 (91.3%) of them in a pigsty. These two species predominated between 20h-21h when 90.4% of the specimens were captured. CONCLUSIONS: Five sandfly species, N. whitmani, N. neivai, Migonemyia migonei, Pintomyia pessoai and Pintomyia fischeri, potential vectors of cutaneous leishmaniasis, were captured. The importance of the two former species is emphasized, since both presented similar behavior in regard to seasonal period, hourly frequency and predominance in the anthropic environment. Besides, N. whitmani was the most predominant species. 相似文献
968.
Vicente AC Teixeira LF Iniguez-Rojas L Luna MG Silva L Andrade JR Guth BE 《Transactions of the Royal Society of Tropical Medicine and Hygiene》2005,99(9):669-674
The relationship between enteropathogens and severe diarrhoea in the Brazilian Amazon is poorly understood. In 1998, outbreaks of acute diarrhoea clinically diagnosed as cholera occurred in two small villages localized far from the main cholera route in the Brazilian rainforest. PCR was performed on some enteropathogens and heat-labile (LT) and/or heat-stable (STh) toxin genes, the virulence determinants of enterotoxigenic Escherichia coli (ETEC), were detected. Further characterization of ETEC isolates revealed the presence of two clones, one from each outbreak. One presenting serotype O167:H5 harboured LT-I and STh toxin genes and expressed the CS5CS6 colonization factor. The other, a non-typeable serotype, was positive for the LT-I gene and expressed the CS7 colonization factor. The current study demonstrates the importance of molecular diagnosis in regions such as the Amazon basin, where the enormous distances and local support conditions make standard laboratory diagnosis difficult. Here we also show that the mis-identified cholera cases were in fact associated with ETEC strains. This is the first report of ETEC, molecularly characterized as the aetiological agent of severe diarrhoea in children and adults in the Brazilian Amazon Rainforest. 相似文献
969.
970.
This study examines the patient in group psychotherapy, describing factors that provide changes during the process and the particularities of this therapeutic mode. Based on the available literature and the authors' systematic experience throughout thirty years of group therapeutic work, the variables that determine the commitment of the group members in a productive and well-succeeded therapeutic relation are discussed. It is emphasized how the patients assimilate the psychotherapeutic process and the way in which they participate in achieving their own improvement. 相似文献