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41.
The ultrastructure ofCucullosporella mangrovei ascospores is described. Mature ascospores possess two wall layers, an outer electron-dense episporium and an innermost tripartite
mesosporium. Episporial elaborations form electrondense spore wall ornamentations from which extend fibrils that may constitute
a highly hydrated exosporium which was not visualised at either the scanning electron microscope or light microscope level.
Ascospores possess a hamate appendage at each pole which unfolds in seawater to form a long thread. Ultrastructurally the
polar appendage comprises folded fibro-granular electron-dense material and fine fibrils. The fibrils form a matrix around
and within the fibro-granular appendage and around the entire unreleased ascospore. These fibrils have not been observed associated
with the ascospore appendages in other species of the Halosphaeriales and are a discrete and new appendage component. The
fibro-granular appendage and fibrils are bounded by the outer delimiting membrane which is absent around released ascospores.
The nature of the spore appendage is compared with that of other marine and freshwater ascomycetes and the taxonomic assignment
of the species is discussed. 相似文献
42.
M. Rahamah Bivi M.D. Siti Noor Farhana A.S. Idris K. Susilawati M. Sariah 《Archives Of Phytopathology And Plant Protection》2013,46(9):1120-1135
The effect of calcium, copper ions and salicylic acid (SA) amendment on the incidence of basal stem rot and activity of secondary metabolites in oil palm seedlings were investigated in glasshouse study. Disease incidence (DI) in positive control (T8) was 75% at nine months after inoculation (9 MAI). However, weekly pre-immunisation with Ca2+?+?Cu2+?+?SA prior to inoculation significantly suppressed DI and delayed disease onset as noted in T7. In the present study, the lowest %DI was observed in T7 (15%) followed by T1, T5, T6, T3, T4 and T2. The Ca2+, Cu2+ and SA amendments were resulted in earlier and higher accumulation of plant secondary metabolites as noted in leaves, stems and root tissues in response to invasion by Ganoderma boninense. High total phenolic content concentration was detected in T7 (leaf: 233.38 ± 0.12 mg/g; stem: 132.78 ± 0.04 mg/g and root: 86.98 ± 0.28 mg/g). Similar trend was obtained in peroxidase activity, total lignin content and hydrogen peroxide scavenging activity. These results suggested that it could be due to the accumulation of phenolics, peroxidase activities, lignin content and hydrogen peroxide scavenging activities in oil palm seedling tissues which might have collectively contributed to induce resistance against G. boninense. 相似文献
43.
Wui Ann Woon Paul B. Ravindran Piyasiri Ekanayake Siti Amirah Yivonne Y.F. Lim Christopher H.S. Vun Jamsari Khalid 《Reports of Practical Oncology and Radiotherapy》2018,23(5):346-359
Aim
The aim of this study was to investigate the sensitivity of the trajectory log file based quality assurance to detect potential errors such as MLC positioning and gantry positioning by comparing it with EPID measurement using the most commonly used criteria of 3%/3?mm.Materials and methods
An in-house program was used to modified plans using information from log files, which can then be used to recalculate a new dose distribution. The recalculated dose volume histograms (DVH) were compared with the originals to assess differences in target and critical organ dose. The dose according to the differences in DVH was also compared with dosimetry from an electronic portal imaging device.Results
In all organs at risk (OARs) and planning target volumes (PTVs), there was a strong positive linear relationship between MLC positioning and dose error, in both IMRT and VMAT plans. However, gantry positioning errors exhibited little impact in VMAT delivery. For the ten clinical cases, no significant correlations were found between gamma passing rates under the criteria of 3%/3?mm for the composite dose and the mean dose error in DVH (r?<?0.3, P?>?0.05); however, a significant positive correlation was found between the gamma passing rate of 3%/3?mm (%) averaged over all fields and the mean dose error in the DVH of the VMAT plans (r?=?0.59, P?<?0.001).Conclusions
This study has successfully shown the sensitivity of the trajectory log file to detect the impact of systematic MLC errors and random errors in dose delivery and analyzed the correlation of gamma passing rates with DVH. 相似文献44.
Abdul Hafiz Ab Majid Hamady Dieng Siti Salbiah Ellias Faezah Syukriah Sabtu Abd Hafis Abd Rahim Tomomitsu Satho 《Journal of Asia》2018,21(1):46-51
Odor sensation is a sensory modality of considerable significance in the foraging behavior and interactional organization of ants. In the food bait technology, smell is the basis of attraction, which, in turn, is the line of bait use and a key parameter for judging efficacy. Yet, the currently available baits possess low attractiveness to many ant pests. Hence, strategies to produce ant bait with increased attractiveness are needed. Despite evidence that coffee has a diverse aroma complex that affects the behavior of honey bees and ants, its attraction to house-invading ants has yet to be investigated. In a series of Y-tube olfactometer bioassays, we examined the behavioral responses of Tapinoma indicum (TI), Monomorium pharaonis (MP) and Solenopsis geminata (SG) to various coffee-induced odor stimuli, comprised of extracts from Arabica, Robusta and Liberica. All coffee extracts showed an influence on the behavior of TI, MP and SG workers, with Arabica showed the most significant influence to the tested ants. The workers of TI, MP and SG were more attracted to the odor of 0.01% Arabica extract (ONE), in comparison with 0.05% Arabica extract (TWO) or 0.10% Arabica extract (THREE). Arabica extract mixed with sugar (S) elicited a significant attraction from workers of all three species in a balanced competition with either unsweetened Arabica extract or water. These results indicated that coffee, particularly Arabica, was attractive to the foragers of TI, MP and SG, thus, the use of coffee as a novel stimulus agent seems plausible in ant bait development. 相似文献
45.
Siti Maziras Makhtar Azlan Husin Abdul Aziz Baba Ravindran Ankathil 《Journal of genetics》2018,97(4):835-842
Imatinib mesylate (IM), a well-established gold standard drug in the treatment of chronic myeloid leukaemia (CML), is a synthetic tyrosine kinase inhibitor. Despite excellent efficacy, a significant number of patients on IM therapy develop resistance to IM. Currently, great focus has been laid on the effect of interindividual pharmacogenetic variability on IM treatment responses. IM uptake is mediated by the hOCT1 protein encoded by the solute carrier 22 gene (SLC22A1). The current study investigated the impact of few single-nucleotide polymorphisms (SNPs) of SLC22A1 on mediating resistance and/or good response to IM among 278 Malaysian CML patients (146 IM-resistant group and 132 IM good response group) undergoing IM therapy on 400 mg daily. Our results showed that the allelic frequencies of heterozygous (CG) and homozygous variant (GG) genotypes of SLC22A1 C480G were significantly higher in the IM-resistant group compared with the IM good response group (41.8% versus 30.3% and 10.9% versus 4.5% with P values of 0.047 and 0.048, respectively). On evaluating the association of genotypes with risk of IM resistance development, heterozygous (CG) and homozygous (GG) variant genotypes showed significantly higher risk for developing resistance to IM treatment with odds ratio (OR): 1.901 (95% confidence interval (CI): 1.142–3.163, \(P=0.013\)) and 3.324 (95% CI: 1.235–8.947, \(P=0.017\)), respectively. Two SNPs and two insertions/deletions were detected in exon 7 of SLC22A1. For exon 7, 1222AA carriers together with the presence of both the 8-bp insertion and 3-bp deletion, and M420del alleles showed higher possibility of developing resistance towards IM treatment. Our results warrant the need of genotyping this SNP in terms of modulating IM treatment in CML patients. 相似文献
46.
Noraina Mohd Bakri Siti Fatimah Ibrahim Nurul Atikah Osman Nurhaslina Hasan Farah Hanan Fathihah Jaffar Zulaiha Abdul Rahman Khairul Osman 《Saudi Journal of Biological Sciences》2016,23(1):S50-S55
Apoptosis is a programed cell death that is vital for tissue homeostasis. However, embryo apoptosis had been known to be related to embryo fragmentation which should be avoided in in vitro fertilization (IVF). The purpose of this study was to evaluate the relationship of embryo apoptosis with the grade of immature oocytes and cleavage stage of in vitro produced (IVP) cattle embryos. This study consisted of 345 oocytes collected through ovary slicing. Immature oocytes were graded as A, B and C. This grading was based on cumulus cell thickness and compactness. All oocytes then underwent an in vitro maturation (IVM) procedure. An IVF was done 24 h after IVM culture. Prior to staining, stage of cleaved embryos was determined and classified as either 2, 4, 8 or >8-cell embryo stage. Apoptosis status of cleaved IVP embryos was determined by using annexin V-FITC staining technique at 48 and 72 h post insemination (hpi). Apoptosis status for each embryo was classified as either early or late. The result showed that there was no significant difference (p > 0.05) of apoptosis status among grade A, B and C embryos. All grades of oocytes showed embryo apoptosis where 1.5% late apoptosis for grade A, 4.5% and 10.4% of early and late apoptosis for grade B and grade C. Early apoptosis was not seen in grade A embryo. We also noted no significant difference (p > 0.05) of apoptosis status between 2, 4, 8 and >8-cell embryo stage. Early apoptosis was also not seen in >8-cell stage. Even though there were no differences in apoptosis expression between the three classes, the cleavage rate of grade A oocytes was significantly higher (p < 0.01) than grade B and grade C. In conclusion, the apoptosis expression in the embryo can occur regardless of the oocyte quality and the cleavage stage of the embryo produced.Abbreviations: ART, assisted reproductive technologies; BO, Brackett and Oliphant; BSA, bovine serum albumin; CaI, calcium ionophore; CC, cumulus cells; COC, cumulus–oocyte complex; CO2, carbon dioxide; CR1aa, Charles Rosenkran’s 1 amino acid; DNA, deoxyribonucleic acid; DO, denuded oocyte; EA, early apoptosis; FBS, fetal bovine serum; FITC, fluorescein isothiocyanate; FSH, follicle stimulating hormone; GSH, glutathione; hpi, hours post insemination; IVC, in vitro culture; IVF, in vitro fertilization; IVM, in vitro maturation; IVP, in vitro produced; LA, late apoptosis; LH, luteinizing hormone; PBS, phosphate buffered saline; PI, propidium iodide; PS, phosphatidylserine; TUNEL, terminal deoxynucleotidyl transfer-mediated dUTP nick end-labeling. 相似文献
47.
48.
Prediction of Anti‐Alzheimer's Activity of Flavonoids Targeting Acetylcholinesterase in silico
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49.
Iis Siti Jahro Djulia Onggo Susanto Imam Rahayu M. Carmen Muñoz Ana B. Gaspar Maksym Seredyuk Philipp Gütlich José Antonio Real 《Inorganica chimica acta》2008,361(14-15):4047-4054
Three new compounds formulated (ClO4)2[Fe(pq)3] (1), (BF4)2[Fe(pq)3] · EtOH (2) and {(ClO4)[MnCr(C2O4)3][Fe(pq)2(H2O)2]} (3), where pq is 2,2′-pyridylquinoline, have been synthesised and characterised. Despite the different crystal packing exhibited by 1 and 2, the cationic species [Fe(pq)3]2+ are structurally quite similar. At 293 K, the Fe–N bond lengths are characteristic of the iron(II) in the high-spin state. In contrast to 1, 2 undergoes a continuous spin transition. Indeed, at 95 K its structure experiences a noticeable change in the Fe–N bonds and angles, i.e. the Fe–N bonds shorten by 0.194 Å on the average. The magnetic behaviour confirms that 1 is fully high-spin in the 4–300 K temperature range while 2 shows a spin transition centred at T1/2 = 150 K. The corresponding enthalpy, entropy and interaction parameter are ΔH = 7.49 kJ mol?1, ΔS = 50 J K?1 mol?1and Γ = 1.35 kJ mol?1. Compound 3 has been obtained as a microcrystalline powder. The magnetic properties of 3 point at the occurrence of ferromagnetic coupling below 100 K and the onset of a ferromagnetic ordering below 10 K (Weiss constant equal to 6.8 K). The Mössbauer spectra of 3 show the occurrence of a magnetic order at T ? 4.2 K. 相似文献
50.
Mee Lee Looi Saiful Anuar Karsani Mariati Abdul Rahman Ahmad Zailani Hatta Mohd Dali Siti Aishah Md Ali Wan Zurinah Wan Ngah Yasmin Anum Mohd Yusof 《Journal of biosciences》2009,34(6):917-925
Although cervical cancer is preventable with early detection, it remains the second most common malignancy among women. An understanding of how proteins change in their expression during a particular diseased state such as cervical cancer will contribute to an understanding of how the disease develops and progresses. Potentially, it may also lead to the ability to predict the occurrence of the disease. With this in mind, we aimed to identify differentially expressed proteins in the plasma of cervical cancer patients. Plasma from control, cervical intraepithelial neoplasia (CIN) grade 3 and squamous cell carcinoma (SCC) stage IV subjects was resolved by two-dimensional gel electrophoresis and the resulting proteome profiles compared. Differentially expressed protein spots were then identified by mass spectrometry. Eighteen proteins were found to be differentially expressed in the plasma of CIN 3 and SCC stage IV samples when compared with that of controls. Competitive ELISA further validated the expression of cytokeratin 19 and tetranectin. Functional analyses of these differentially expressed proteins will provide further insight into their potential role(s) in cervical cancer-specific monitoring and therapeutics. 相似文献