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41.
Chengjun Li Yi Zhang Xiaopei Yun Yanyun Wang Ming Sang Xing Liu Xingxing Hu Bin Li 《Insect molecular biology》2014,23(5):587-597
Methuselah (Mth) is associated with lifespan, stress resistance and reproduction in Drosophila melanogaster, but Mth is not present in nondrosophiline insects. A number of methuselah‐likes (mthls) have been identified in nondrosophiline insects, but it is unknown whether the functions of mth are shared by mthls or are divergent from them. Five mthls have been identified in Tribolium castaneum. Although they have different developmental expression patterns, they all enhance resistance to starvation. Only mthl1 and mthl2 enhance resistance to high temperature, whereas mthl4 and mthl5 negatively regulate oxidative stress in T. castaneum. Unlike in the fly with mth mutation, knockdown of mthls, except mthl3, shortens the lifespan of T. castaneum. Moreover, mthl1 and mthl2 are critical for Tribolium development. mthl1 plays important roles in larval and pupal development and adult eclosion, while mthl2 is required for eclosion. Moreover, mthl1 and mthl2 silencing reduces the fertility of T. castaneum, and mthl1 and mthl4 are also essential for embryo development. In conclusion, mthls have a significant effect on insect development, lifespan, stress resistance and reproduction. These results provide experimental evidence for functional divergence among mthls/mth and clues for the signal transduction of Mthls. 相似文献
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Muscle functional MRI analysis of trunk muscle recruitment during extension exercises in asymptomatic individuals
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E. M. D. De Ridder J. O. Van Oosterwijck A. Vleeming G. G. Vanderstraeten L. A. Danneels 《Scandinavian journal of medicine & science in sports》2015,25(2):196-204
The present study examined the activity levels of the thoracic and lumbar extensor muscles during different extension exercise modalities in healthy individuals. Therefore, 14 subjects performed four different types of extension exercises in prone position: dynamic trunk extension, dynamic–static trunk extension, dynamic leg extension, and dynamic–static leg extension. Pre‐ and post‐exercise muscle functional magnetic resonance imaging scans from the latissimus dorsi, the thoracic and lumbar parts of the longissimus, iliocostalis, and multifidus were performed. Differences in water relaxation values (T2‐relaxation) before and after exercise were calculated (T2‐shift) as a measure of muscle activity and compared between extension modalities. Linear mixed‐model analysis revealed higher lumbar extensor activity during trunk extension compared with leg extension (T2‐shift of 5.01 ms and 3.55 ms, respectively) and during the dynamic–static exercise performance compared with the dynamic exercise performance (T2‐shift of 4.77 ms and 3.55 ms, respectively). No significant differences in the thoracic extensor activity between the exercises could be demonstrated. During all extension exercises, the latissimus dorsi was the least activated compared with the paraspinal muscles. While all extension exercises are equivalent effective to train the thoracic muscles, trunk extension exercises performed in a dynamic–static way are the most appropriate to enhance lumbar muscle strength. 相似文献
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《Journal of pharmaceutical sciences》2019,108(7):2207-2237
This review describes the landscape of novel modalities such as cell and gene therapies, viruses, other novel biologics, oligomers, and emerging technologies, including modern analytics. We summarize the regulatory history and recent landmark developments in some major markets and examine specific chemistry, manufacturing, and controls (CMC) challenges, including suggestions for exploration of potential science-based approaches in support of regulatory strategy development from an industry perspective. In addition, we evaluate the economic factors contributing to patient access to innovation and discuss the impact of regulation. There is a desperate need for a consistent form of regulation where global approaches to regulatory strategies can be harmonized, and specific CMC challenges can be dealt with using the appropriate science and risk-based tools. Although these tools are well described in current guidance documents, the specifics of applicability to complex novel modalities can still result in differing regulatory advice and outcomes. The future goals for efficiently regulating innovative modalities and technologies could be aided by more regulatory harmonization, regulatory education, and industry cooperation through consortia, enabling industry to supply key information to regulators in a transparent yet well-defined manner, and utilizing mutually understood risk-benefit analyses to produce drugs with appropriate safety, efficacy, and quality characteristics. 相似文献
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IntroductionCavernous hemangioma of the skull is a rare pathological diagnosis, accounting for 0.2% of bone tumors and 7% of skull tumors. Usually calvarial bone cavernous hemangioma are associated with a benign clinical course and, despite their enlargement and subsequent erosion of the surrounding bone, the inner table of the skull remains intact and the lesion is completely extracranial.Presentation of a caseThe authors present the unique case of a huge left frontal bone cavernous malformation with intradural extension and brain compression determining a right hemiparesis.DiscussionCalvarial cavernous hemangiomas are benign tumors. They arise from vessels in the diploic space and tend to involve the outer table of the skull with relative sparing of the inner table. More extensive involvement of the inner table and extradural space is very unusual and few cases are reported in literature. To the best of our knowledge, intradural invasion of calvarial hemangioma has not been previously reported.ConclusionOur case highlights the possibility of an aggressive course of this rare benign pathology. 相似文献
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《Journal of cardiology》2014,63(4):313-319
ObjectivesUsing newly developed ultrasonic technology, we attempted to disclose the characteristics of the left ventricular (LV) contraction–extension (C–E) property, which has an important relationship to LV function.MethodsStrain rate (SR) distribution within the posterior wall and interventricular septum was microscopically measured with a high accuracy of 821 μm in spatial resolution by using the phase difference tracking method. The subjects were 10 healthy men (aged 30–50 years).ResultsThe time course of the SR distribution disclosed the characteristic C–E property, i.e. the contraction started from the apex and propagated toward the base on one hand, and from the epicardial side toward the endocardial side on the other hand. Therefore, the contraction of one area and the extension of another area simultaneously appeared through nearly the whole cardiac cycle, with the contracting part positively extending the latter part and vice versa. The time course of these propagations gave rise to the peristalsis and the bellows action of the LV wall, and both contributed to effective LV function.The LV contraction started coinciding in time with the P wave of the electrocardiogram, and the cardiac cycle was composed of 4 phases, including 2 types of transitional phase, as well as the ejection phase and slow filling phase. The sum of the measurement time duration of either the contraction or the extension process occupied nearly equal duration in normal conditions.ConclusionThe newly developed ultrasonic technology revealed that the SR distribution was important in evaluating the C–E property of the LV myocardium. The harmonious succession of the 4 cardiac phases newly identified seemed to be helpful in understanding the mechanism to keep long-lasting pump function of the LV. 相似文献
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