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21.
Nor Aliza AR Bedick JC Rana RL Tunaz H Hoback WW Stanley DW 《Comparative biochemistry and physiology. Part A, Molecular & integrative physiology》2001,128(2):251-257
We report on the presence of high proportions of arachidonic acid (20:4n-6) and eicosapentaenoic acid (20:5n-3) in the tissue lipids of adult fireflies, Photinus pyralis. Arachidonic acid typically occurs in very small proportions in phospholipids (PLs) of terrestrial insects, ranging from no more than traces to less than 1% of PL fatty acids, while 20:5n-3 is often missing entirely from insect lipids. Contrarily, 20:4n-6 made up approximately 21% of the PL fatty acids prepared from whole males and females, and from heads and thoraces prepared from males. Proportions of 20:4n-6 associated with PLs varied among tissues, including approximately 8% for male gut epithelia, 13% for testes, and approximately 25% for light organs and body fat from males. Substantial proportions of 20:5n-3 were also associated with PLs prepared from male firefly tissues, including 5% for body fat and 8% for light organs. Because 20:4n-6 and 20:5n-3 are precursors for biosynthesis of prostaglandins and other eicosanoids, we considered the possibility that firefly tissues might produce eicosanoids at exceptionally high rates. Preliminary experiments indicated otherwise. Hence, fireflies are peculiar among terrestrial insects with respect to maintaining high proportions of PL 20:4n-6 and 20:5n-3. 相似文献
22.
Nor?Aini?Abdul?Rahman Yoshihito?Shirai Kazuyuki?ShimizuEmail author Mohd?Ali?Hassan 《Biotechnology and Bioprocess Engineering》2002,7(5):281-288
RecombinantEscherichia coli strain harboring the λp
R-p
L promotor and heterologus poly-β-hydroxybutyrate (PHB) biosynthesis genes was used to investigate the effect of culture conditions
on the efficient PHB production. The expression ofphb genes was induced by a temperature upshift from 33°C to 38°C. The protein expression levels were measured by using two-dimensional
electrophoresis, and the enzyme activities were also measured to understand the effect of culture temperature, carbon sources,
and the dissolved oxygen (DO) concentration on the metabolic regulations. AcetylCoA is an important branch point for PHB production.
The decrease in DO concentration lowers the citrate synthase activity, thus limit the flux toward the TCA cycle, and increase
the flux for PHB production. Since NADPH is required for PHB production, the PHB production does not continue leading the
overproduction of acetate and lactate. Based on these observations, a new operation was considered where DO concentration
was changed periodically, and it was verified its usefulness for the efficient PHB production by experiments. 相似文献
23.
Eva Norén Selinus Yasmina Molero Paul Lichtenstein Tomas Larson Sebastian Lundstr?m Henrik Anckars?ter Clara Hellner Gumpert 《PloS one》2015,10(9)
Objective
Neurodevelopmental problems (NDPs) may influence the transition from childhood to adolescence. Our aim was to study long-term psychosocial outcomes of NDPs, focusing on ADHD.Method
Data was collected through a telephone interview with parents of twins at ages 9 or 12 years. NDP screen-positive children were clinically assessed at age 15; N = 450. Psychosocial outcome concerning peers, school, internalizing problems, antisocial behavior, alcohol misuse, drug misuse, and impaired daily functioning was examined.Results
Even after controlling for other NDP comorbidity, screen-positivity for ADHD doubled or tripled the odds of later psychosocial problems. When controlling for parental education level, the significant effect of ADHD remained only for antisocial behavior and impaired daily functioning.Conclusions
Signs of NDPs as well as other psychiatric diagnoses at ages 9 or 12 years are associated with a more problematic adolescence. However, despite the presence of comorbidity, early ADHD symptoms stand out as the most important risk factor for later antisocial development and impaired daily functioning. 相似文献24.
Noor Adelyna Mohammed Akib Bui Minh Tam Preeda Phumee Muchlisin Zainal Abidin Saied Tamadoni Peter B. Mather Siti Azizah Mohd Nor 《PloS one》2015,10(3)
Phylogeographic patterns and population structure of the pelagic Indian mackerel, Rastrelliger kanagurta were examined in 23 populations collected from the Indonesian-Malaysian Archipelago (IMA) and the West Indian Ocean (WIO). Despite the vast expanse of the IMA and neighbouring seas, no evidence for geographical structure was evident. An indication that R. kanagurta populations across this region are essentially panmictic. This study also revealed that historical isolation was insufficient for R. kanagurta to attain migration drift equilibrium. Two distinct subpopulations were detected between the WIO and the IMA (and adjacent populations); interpopulation genetic variation was high. A plausible explanation for the genetic differentiation observed between the IMA and WIO regions suggest historical isolation as a result of fluctuations in sea levels during the late Pleistocene. This occurrence resulted in the evolution of a phylogeographic break for this species to the north of the Andaman Sea. 相似文献
25.
Objectives
Recent evidence suggests that suicidal ideation is increased among university students, it is essential to increase our knowledge concerning the etiology of suicidal ideation among university students. This study was conducted to examine the relationships between problem-solving skills appraisal, hardiness, and suicidal ideation among university students. In addition, this study was conducted to examine problem-solving skills appraisal (including the three components of problem-solving confidence, approach-avoidance style, and personal control of emotion) as a potential mediator between hardiness and suicidal ideation.Methods
The participants consisted of 500 undergraduate students from Malaysian public universities.Results
Structural Equation Modelling (SEM) estimated that undergraduate students with lower hardiness, poor problem-solving confidence, external personal control of emotion, and avoiding style was associated with higher suicidal ideation. Problem-solving skills appraisal (including the three components of problem-solving confidence, approach-avoidance style, and personal control of emotion) partially mediated the relationship between hardiness and suicidal ideation.Conclusion
These findings underline the importance of studying mediating processes that explain how hardiness affects suicidal ideation. 相似文献26.
Wan Faridah Akmal Wan Jusoh Nor Rasidah Hashim Zelina Z. Ibrahim 《Wetlands Ecology and Management》2010,18(3):367-373
Pteroptyx fireflies are commonly reported to congregate in large numbers in mangroves. Not much is known about the relationships between
firefly distribution and abundance with specific mangrove vegetation assemblages. We conducted a study to investigate the
vegetation assemblages that structure the distribution and abundance of Pteroptyx tener in Peninsular Malaysia. The distribution and abundance of fireflies were assessed along an 8 km stretch of mangroves in Sepetang
estuary using visual assessment. Statistical analysis was carried out to test the correlation between length of display section
and percentage cover of P. tener colonies and the relationship between percentage cover of fireflies with different vegetation assemblages. Five distinct
vegetation assemblages were identified comprising different combination of four mangrove species. It was found that shorter
display sections had higher percentage cover of P. tener colonies. In addition, vegetation assemblage which consisting of mainly Sonneratia caseolaris and Nypa fruticans was the most preferred type. The results of this study point to the necessity to consider not only a single mangrove species
but the entire vegetation assemblage for firefly conservation. 相似文献
27.
28.
Selao TT Branca R Chae PS Lehtiö J Gellman SH Rasmussen SG Nordlund S Norén A 《Journal of proteome research》2011,10(6):2703-2714
The chromatophore membrane of the photosynthetic diazotroph Rhodospirillum rubrum is of vital importance for a number of central processes, including nitrogen fixation. Using a novel amphiphile, we have identified protein complexes present under different nitrogen availability conditions by the use of two-dimensional Blue Native/SDS-PAGE and NSI-LC-LTQ-Orbitrap mass spectrometry. We have identified several membrane protein complexes, including components of the ATP synthase, reaction center, light harvesting, and NADH dehydrogenase complexes. Additionally, we have identified differentially expressed proteins, such as subunits of the succinate dehydrogenase complex and other TCA cycle enzymes that are usually found in the cytosol, thus hinting at a possible association to the membrane in response to nitrogen deficiency. We propose a redox sensing mechanism that can influence the membrane subproteome in response to nitrogen availability. 相似文献
29.
30.
Low KO Mahadi NM Rahim RA Rabu A Abu Bakar FD Murad AM Illias RM 《Journal of industrial microbiology & biotechnology》2011,38(9):1587-1597
Direct transport of recombinant protein from cytosol to extracellular medium offers great advantages, such as high specific
activity and a simple purification step. This work presents an investigation on the potential of an ABC (ATP-binding cassette)
transporter system, the hemolysin transport system, for efficient protein secretion in Escherichia coli (E. coli). A higher secretory production of recombinant cyclodextrin glucanotransferase (CGTase) was achieved by a new plasmid design
and subsequently by optimization of culture conditions via central composite design. An improvement of at least fourfold extracellular
recombinant CGTase was obtained using the new plasmid design. The optimization process consisted of 20 experiments involving
six star points and six replicates at the central point. The predicted optimum culture conditions for maximum recombinant
CGTase secretion were found to be 25.76 μM IPTG, 1.0% (w/v) arabinose and 34.7°C post-induction temperature, with a predicted
extracellular CGTase activity of 68.76 U/ml. Validation of the model gave an extracellular CGTase activity of 69.15 ± 0.71 U/ml,
resulting in a 3.45-fold increase compared to the initial conditions. This corresponded to an extracellular CGTase yield of
about 0.58 mg/l. We showed that a synergistic balance of transported protein and secretory pathway is important for efficient
protein transport. In addition, we also demonstrated the first successful removal of the C-terminal secretion signal from the transported fusion protein by thrombin proteolytic cleavage. 相似文献