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341.
David A. Price Evans Mohammad Tariq Rofaida Dafterdar Hussa Al Hussaini Samia H. Sobki 《Biological trace element research》2009,130(3):262-272
This experiment was carried out to test the null hypothesis that intramuscular trivalent chromium administration would not
remove lipids from the heart and ascending aorta of the hyoercholesterolemic rabbits and would not lower their serum cholesterol
levels. A novel computer-based method, previously described, was used to assess the sizes of the intracardiac and aortic lesions.
Clinical chemistry and histopathology were performed through routine methods. The sizes of the lipid deposits in the coronary
vasculature of the hypercholesterolemic rabbits were greatly reduced as a result of the intramuscular chromium chloride injections.
Lipid deposits in the ascending aorta were similarly reduced, as well as the serum cholesterol concentrations. The terminal
serum chromium concentrations in the chromium-treated group were in the range of 3,258–4,513 μg/L, whereas, in the untreated
animals, the concentrations were 3.2 to 6.3 μg/L. The general condition of the chromium-treated animals was good and they
were continuing to gain weight up to the time they were killed. However, it was found that their liver function tests had
become abnormal even though there was no evidence of hepatic histopathological lesions specifically affecting the chromium-treated
group. The kidney function tests and histopathology were normal. These findings suggest that a more aggressive approach than
those tried hitherto might be useful in treating atherosclerotic human patients with chromium. 相似文献
342.
Samia Oueslati Najoua Karray-Bouraoui Houneïda Attia Mokded Rabhi Riadh Ksouri Mokhtar Lachaal 《Acta Physiologiae Plantarum》2010,32(2):289-296
Mentha pulegium L. is a medicinal and aromatic plant belonging to the Labiatae family present in the humid to the arid bioclimatic regions
of Tunisia. We studied the effect of different salt concentrations on plant growth, mineral composition and antioxidant responses.
Physiological and biochemical parameters were assessed in the plant organs after 2 weeks of salt treatment with 25, 50, 75
and 100 mM NaCl. Results showed that, growth was reduced even by 25 mM, and salt effect was more pronounced in shoots (leaves
and stems) than in roots. This growth decrease was accompanied by a restriction in tissue hydration and K+ uptake, as well as an increase in Na+ levels in all organs. Considering the response of antioxidant enzymes to salt, leaves and roots reacted differently to saline
conditions. Leaf and root guaiacol peroxidase activity showed an increase by different concentration of NaCl, but superoxide
dismutase activity in the same organs showed a slight modification in NaCl-treated leaves and roots. Moreover, polyphenol
contents and antioxidant activity were analysed in M. pulegium leaves and roots under salt constraint. The analysis showed an increase of total polyphenol content (2.41–8.17 mg gallic
acid equivalent g−1 dry weight) in leaves. However, methanol extract of leaves at 100 mM NaCl displayed the highest DPPH· scavenging ability
with the lowest IC50 value (0.27 μg ml−1) in comparison with control which exhibited IC50 equal to 0.79 μg ml−1. 相似文献
343.
James Inkster Kuo-Shyan Lin Samia Ait-Mohand Simon Gosselin François Bénard Brigitte Guérin Maral Pourghiasian Thomas Ruth Paul Schaffer Tim Storr 《Bioorganic & medicinal chemistry letters》2013,23(13):3920-3926
Acetylene-bearing 2-[18F]fluoropyridines [18F]FPy5yne and PEG-[18F]FPyKYNE were prepared via efficient nucleophilic heteroaromatic [18F]fluorination of their corresponding 2-trimethylammoniumpyrdinyl precursors. The prosthetic groups were conjugated to azide- and PEG3-modified bombesin(6–14) analogues via copper-catalyzed azide–alkyne cycloaddition couplings to yield mono- and di-mini-PEGylated ligands for PET imaging of the gastrin- releasing peptide receptor. The PEG3- and PEG2/PEG3-bearing 18F peptides showed decreased lipophilicity relative to an analogous non-mini-PEGylated 18F peptide. Assessment of water-soluble peptide pharmacokinetics and tumour-targeting capabilities in a mouse model of prostate cancer is currently underway. 相似文献
344.
ABSTRACT: BACKGROUND: Pregnancies complicated by pre-existing diabetes mellitus (PDM) are associated with a high rate of adverse outcomes, including an increased miscarriage rate, preterm delivery, preeclampsia, perinatal mortality and congenital malformations; compared to the background population. The objectives of this study are to determine the prevalence of PDM and to investigate the maternal and the neonatal outcomes of women with PDM. METHODS: This is a retrospective cohort study for women who delivered in King Khalid University Hospital (KKUH) during the period of January 1st to the 31st of December 2008. The pregnancy outcomes of the women with PDM were compared to the outcomes of all non-diabetic women who delivered during the same study period. RESULTS: A total of 3157 deliveries met the inclusion criteria. Out of the study population 116 (3.7%) women had PDM. There were 66 (57%) women with T1DM and 50 (43%) women with T2DM. Compared to non-diabetic women those with PGMD were significantly older, of higher parity, and they had more previous miscarriages. Women with PDM were more likely to be delivered by emergency cesarean section (C/S), OR 2.67, 95% confidence intervals (CI) (1.63-4.32), P < 0.001, or elective C/S, OR 6.73, 95% CI (3.99-11.31), P < 0.001. The neonates of the mothers with PDM were significantly heavier, P < 0.001; and more frequently macrosomic; OR 3.97, 95% CI (2.03-7.65), P = 0.002. They more frequently have APGAR scores <7 in 5 minutes, OR 2.61, 95% CI (0.89-7.05), P 0.057 and more likely to be delivered at <37 gestation weeks, OR 2.24, 95% CI (1.37- 3.67), P 0.003. The stillbirth rate was 2.6 times more among the women with PDM group; however the difference did not reach statistical significance, P 0.084. CONCLUSION: PDM is associated with increased risk for C/S delivery, macrosomia, stillbirth, preterm delivery and low APGAR scores at 5 min. 相似文献
345.
346.
Samia Kaddour Fernando Lpez-Gallego Tahar Sadoun Roberto Fernandez-Lafuente Jose M. Guisan 《Journal of Molecular Catalysis .B, Enzymatic》2008,55(3-4):142-145
Multimeric catalase from Aspergillus niger was immobilized on CNBr activated agarose, increasing the enzyme stability. However, it was found that some enzyme subunits could be desorbed to the supernatant after boiling the enzyme preparation in the presence of SDS or during thermal inactivation. Moreover, a positive enzyme concentration-enzyme stability correlation was detected in the immobilized preparation. This suggested the existence of some dissociation mechanism as a first step in the enzyme inactivation. The treatment of the immobilized enzyme with aldehyde–dextran permitted to fully stabilize its multimeric structure, but even this preparation exhibited an enzyme concentration-stability correlation. The presence of EDTA reduced the enzyme stability, suggesting that some cation could be involved in enzyme stability. It was found that 10 mM Zn2+ increased the enzyme stability of this immobilized–stabilized preparation. Now, the dilution of the biocatalyst did not produce a reduction in the enzyme stability.Thus, we have prepared an immobilized enzyme that does not release any subunit to the medium even after inactivation, and found that Zn2+ has a very positive effect on the stability of this immobilized–stabilized enzyme. 相似文献
347.
Bacterial classification with convolutional neural networks based on different data reduction layers
Samia M. Abd –Alhalem Naglaa F. Soliman S. E. Abd Elrahman Nabil A. Ismail El-Sayed M. El-Rabaie 《Nucleosides, nucleotides & nucleic acids》2020,39(4):493-503
AbstractFor high accuracy classification of DNA sequences through Convolutional Neural Networks (CNNs), it is essential to use an efficient sequence representation that can accelerate similarity comparison between DNA sequences. In addition, CNN networks can be improved by avoiding the dimensionality problem associated with multi-layer CNN features. This paper presents a new approach for classification of bacterial DNA sequences based on a custom layer. A CNN is used with Frequency Chaos Game Representation (FCGR) of DNA. The FCGR is adopted as a sequence representation method with a suitable choice of the frequency k-lengthen words occurrence in DNA sequences. The DNA sequence is mapped using FCGR that produces an image of a gene sequence. This sequence displays both local and global patterns. A pre-trained CNN is built for image classification. First, the image is converted to feature maps through convolutional layers. This is sometimes followed by a down-sampling operation that reduces the spatial size of the feature map and removes redundant spatial information using the pooling layers. The Random Projection (RP) with an activation function, which carries data with a decent variety with some randomness, is suggested instead of the pooling layers. The feature reduction is achieved while keeping the high accuracy for classifying bacteria into taxonomic levels. The simulation results show that the proposed CNN based on RP has a trade-off between accuracy score and processing time. 相似文献
348.
349.
Mohamed A. El-Farrash Mohamed F. Badr Samia A. Hawas Nariman M. El-Nashar Joko Imai Haruko Komoda Yorio Hinuma 《Microbiology and immunology》1988,32(9):981-984
Sera from 3,158 individuals living in northern Egypt were tested for the presence of antibodies against human T-lymphotropic virus type I (HTLV-I) by the newly developed particle agglutination (PA) test. Ten sera gave a positive reaction in the PA test. Eight of these sera were examined further by Western blotting and all of them gave several bands corresponding to HTLV-I structural proteins. Two of the 8 sera gave positive results in the indirect immunofluorescence test. The results indicate the presence of HTLV-I carriers in this area, although at very low incidence (0.063%). 相似文献
350.
Rossana de Aguiar Cordeiro Kharla Rabelo Nobre Patoilo Silviane Bandeira Praciano Delia Jessica Astete Medrano Francisca Jakelyne de Farias Marques Liline Maria Soares Martins Kelsen Dantas Eulalio Antônio de Deus Filho Maria do Amparo Salmito Cavalvanti Maria Auxiliadora Bezerra Fechine Raimunda Samia Nogueira Brilhante Zoilo Pires de Camargo Marcos Fábio Gadelha Rocha José Júlio Costa Sidrim 《Mycopathologia》2013,175(1-2):25-32
Serologic diagnosis has been presented as a safe alternative for coccidioidomycosis. However, commercial kits based on coccidioidal antibodies available in the USA are considered too expensive for laboratories outside that country. In this study, we describe the preparation of antigens for detection of human coccidioidal antibodies by the immunodiffusion test (ID) and enzyme immunoassay (EIA). Antigens were tested against serum samples from patients with coccidioidomycosis, histoplasmosis and paracoccidioidomycosis, as well as healthy individuals. The highest reactivity in the ID tests was seen in the F0-90 antigen. In the EIAs, the best results were obtained with the F60-90 antigen. None of the serum samples from healthy individuals were recognized by any of the antigen extracts tested by ID or EIA. In conclusion, the F0-90 and F60-90 antigens have the potential to be commercially employed in presumptive diagnosis of coccidioidomycosis by ID or EIA, respectively. The tests could improve serological diagnosis of coccidioidomycosis in South America. 相似文献