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981.
Arno Lotar Cordova Jr. Taynná Vernalha Rocha Almeida Cintia Mara da Silva Pedro Argolo Piedade Cristiane Maria Almeida Carlos Genesio Bezzera Lima Jr. Carolina Dutra Rafael Martins Ferreira Marcelo Neves Linhares Valeriy Denyak 《Reports of Practical Oncology and Radiotherapy》2018,23(3):154-160
Aim
Evaluating the recurrence patterns of high-grade astrocytomas in patients who were treated with radiotherapy (RT) plus temozolomide (TMZ).Background
The current literature suggests that reducing the margins added to the CTV does not significantly change the risk of recurrence and overall survival; thus, we decided to analyze our data and to examine the possibility of changing the adopted margins.Materials and methods
From February 2008 till September 2013, 55 patients were treated for high-grade astrocytomas, 20 patients who had been confirmed to have recurrence were selected for the present study. Post-operative MRI was superimposed on the planning CT images in order to correlate the anatomical structures with the treatment targets. Recurrences were defined according to the Response Assessment Criteria for Glioblastoma. The mean margins of the PTVinitial and PTVboost were 1.2 cm and 1.4 cm, respectively. The analysis of the percentage of the recurrence volume (Volrec) within the 100% isodose surface was based on the following criteria: (I) Central: >95% of the Volrec; (II) In-field: 81–95% of the Volrec; (III) Marginal: 20–80% of the Volrec; and (IV) Outside: <20% of the Volrec.Results
Of the 20 patients, 13 presented with central recurrences, 3 with in-field recurrences, 2 with marginal recurrences and 2 with outside recurrences. Therefore, the lower Volrec within 100% of the prescribed dose was considered in the classification.Conclusions
Of the selected patients, 80% had ≥81–95% of the Volrec within 100% of the prescribed dose and predominantly had central or in-field recurrences. These results are comparable with those from the literature. 相似文献982.
We investigated the participation of lipid mediators in an experimental immune complex (IC) arthritis model in rats. The animals were subjected to intraarticular injection of anti-bovine sertLm albumin (BSA) IgG antibodies followed by i.v. injection of BSA. Histopathological analysis of the synovial membranes disclosed infiltration of polymorphonuclear (PMN) cells and vascular congestion. Slight increase in vascular permeability, measured by Evans blue dye extravasation into the joints, was detected after 3 h of arthritis. Cellular influx into the articular cavities was most evident at the sixth hour of arthritis with predominance of PMN. Pretreatment with either indomethacin, a cyclooxygenase inhibitor, or L-660,711, a peptido-leukotriene antagonist, did not inhibit cell infiltration, whereas pretreatment with either L-663,536, a 5-lipoxygenase inhibitor, or L-655,240, a thromboxane antagonist, significantly inhibited the phenomenon. Pretreatment with WEB 2170, a platelet activating factor (PAF) antagonist, also significantly inhibited cell influx. These results suggest that thromboxane, LTB(4) and PAF mediate cell infiltration in this IC arthritis model. 相似文献
983.
Oligonucleotide bias in Bacillus subtilis: general trends and taxonomic comparisons. 总被引:4,自引:0,他引:4 下载免费PDF全文
We present a general analysis of oligonucleotide usage in the complete genome of Bacillus subtilis . Several datasets were built in order to assign various biological contexts to the biased use of words and to reveal local asymmetries in word usage that may be coupled with replication, the control of gene expression and the restriction/modification system. This analysis was complemented by cross-comparisons with the complete genomes of Escherichia coli , Haemophilus influenzae and Methanococcus jannaschii . We have observed a large number of biased oligonucleotides for words of size up to 8, throughout the datasets and species, indicating that such long strict words play an important role as biological signals. We speculate that some of them are involved in interactions with DNA and/or RNA polymerases. An extensive analysis of palindrome abundances and distributions provides the surprising result that prophage-like elements embedded in the genome exhibit a smaller avoidance of restriction sites. This may reinforce a recently proposed hypothesis of a selfish gene phenomena in the transfer of restriction/modification systems in bacteria. 相似文献
984.
985.
Inhibition of Signal Transducer and Activator of Transcription 3 (STAT3) reduces neonatal hypoxic‐ischaemic brain damage 下载免费PDF全文
986.
987.
Effect of green and red light in lipid accumulation and transcriptional profile of genes implicated in lipid biosynthesis in Chlamydomonas reinhardtii 下载免费PDF全文
Alejandro Rocha‐Uribe Ana Silvia Pérez‐Martínez Ángel Gabriel Alpuche‐Solís Ruth Elena Soria‐Guerra 《Biotechnology progress》2016,32(6):1404-1411
Microalgae have the potential to accumulate triacylglycerols under different light spectra. In this work, Chlamydomonas reinhardtii was grown under white (400–700 nm), red (650 nm), and green (550 nm) lights. According to our results, red light (650 nm) has a positive effect in the microalgae growth and chlorophyll concentration. About the lipid content, the control culture (white light‐illuminated) reached a 4.4% of dry cell weight (dcw), whereas the culture grown at 550 nm showed an increase of 1.35‐fold in the lipids accumulation (5.96% dcw). Interestingly, the most significant accumulation was found in the culture grown at 650 nm (14.78% dcw) which means 3.36‐fold higher with respect to the white light‐illuminated culture. The most abundant fatty acids found in lipid extracts obtained from the cultures under different light wavelength were palmitic (C16: 0), oleic (C18: 1n9), stearidonic (C18: 4), and linoleic (C18: 2), which are useful in the biodiesel production. Changes in gene expression in response to different wavelength illuminations were assessed; however, an in‐depth analysis of a larger number of genes involved in lipid biosynthesis is necessary to fully explain the highest accumulation of lipids in the culture grown under red light. This approach will be useful to find a sustainable source of lipids for biodiesel production. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:1404–1411, 2016 相似文献
988.
Matriclans shape populations: Insights from the Angolan Namib Desert into the maternal genetic history of southern Africa 下载免费PDF全文
989.
Physical examinations were performed on 3991 bulls reared in subtropical (75%) and tropical (25%) Mozambique. A culling rate of 16.3% (651 sires) was found. The range of culling rate between farms varied from 3 to 44%. The main culling reasons were a) epididymitis, b) atrophy and/or hypoplasia, and c) testicular fibrosis (contributing to 30.4, 20.9, and 15.2%, respectively, of the culled bulls). Epididymitis-vaginitis (epivag) syndrome was considered the main reason for the high incidence of epididymitis and testicular fibrosis. A highly significant difference (P<0.001) in culling rate for Simmental (37.7%) and Brahman (13.1%) bulls was found. A more comprehensive investigation of culling rate of different breeds used in the country is needed, as well as a program for controlling epivag in the more affected areas. Examining the reproductive organs of the beef bulls in Mozambique before the breeding season is very important to improve fertility in the beef herds. 相似文献
990.
A V Osorio L Servín-González M Rocha A A Covarrubias F Bastarrachea 《Molecular & general genetics : MGG》1984,194(1-2):114-123
Summary Mutants resistant to 80 M L-methionine-DL-sulfoximine (MS) were isolated on glucose-minimal 15 mM NH
+
4
medium plates from Escherichia coli cells which were hypersensitive to this concentration of the analogue by virtue of their harboring glnG mutations. MS-resistant mutants derived from strain MX902 carried, in addition to its glnG74::Tn5 allele, mutations tightly linked to glnA, as shown by P1-mediated transduction experiments. One particular allele, gln-76, which suppressed the MS-sensitivity conferred by glnG74::Tn5 but not its Ntr– phenotype (inability to transport and utilize compounds such as arginine or proline as the only nitrogen sources), was shown to allow constitutive expression of glutamine synthetase in the absence not only of a functional glnG product but also of a functional glnF product. This behavior was found to be cis-dominant in complementation experiments with F'14 merogenotes. In an otherwise wild-type genetic background as in MX929 (gln-76 glnA
+ glnL+ glnG+ glnF+), however, normal activation, mediated by the glnG and glnF products was preferred over that mediated by gln-76. 相似文献