南瓜高效再生体系的建立

南瓜(Cucurbita moschata)再生率较低, 为建立高效的南瓜再生体系, 以南瓜子叶为外植体, 进行35组不同激素浓度的不定芽诱导研究。结果表明, 南瓜再生受培养基中激素浓度和配比的影响, 适宜浓度6-苄氨基腺嘌呤(6-BA)能有效促进不定芽形成; 单独使用脱落酸(ABA)诱导使南瓜子叶发黄, 但与6-BA组合使用可显著提高外植体的再生能力, 1.0 mg∙L ^-16-BA与0.5 mg∙L ^-1ABA组合南瓜芽再生率高达90.26%。将不定芽置于MS培养基中进行生根培养, 再生苗移栽易成活。从子叶接种到苗再生约需70天。     

南瓜高效再生体系的建立

南瓜(Cucurbita moschata)再生率较低, 为建立高效的南瓜再生体系, 以南瓜子叶为外植体, 进行35组不同激素浓度的不定芽诱导研究。结果表明, 南瓜再生受培养基中激素浓度和配比的影响, 适宜浓度6-苄氨基腺嘌呤(6-BA)能有效促进不定芽形成; 单独使用脱落酸(ABA)诱导使南瓜子叶发黄, 但与6-BA组合使用可显著提高外植体的再生能力, 1.0 mg?L ^-16-BA与0.5 mg?L ^-1ABA组合南瓜芽再生率高达90.26%。将不定芽置于MS培养基中进行生根培养, 再生苗移栽易成活。从子叶接种到苗再生约需70天。     

Sensori-motor transformations in the brain (with a critique of the tensor theory of cerebellum)

Section 1 lists 12 points which must be addressed by neural models of sensorimotor coordination. Section 2 addresses the problem of extrapolating motor output from noisy data or from sensory input. The Pellionisz-Llinas cerebellar lookahead module addresses this problem for the noise-free case, and we suggest theoretical and experimental tests of the model; we then suggest the investigation of neural analogs of the Kalman-Bucy filter. Section 3 offers a brief exposition of mechanics in a tensor framework to provide the irreducible minimum of mathematical machinery to evaluate the Pellionisz-Llinás tensor theory of brain function and to suggest fruitful new hypotheses. Our critique of this theory in section 4 leads us to conclude that what they offer is based on metaphorical use of terminology from Euclidean tensors, not on rigorous application of the mathematics of tensor analysis. The central claim of their theory--that the input is a covariant intention vector transformed by a metric tensor encoded in the cerebellum to a contravariant execution vector--has not been substantiated and probably cannot be substantiated. However, we do point the way to further use of tensor analysis in the study of neural control of movement. The concluding section then returns to the points raised in section 1 with a highly selective survey of models of cerebellum and tectum.     

Dual specific phosphatases (DUSPs) in cardiac hypertrophy and failure

Pressure overload and other stress stimuli elicit a host of adaptive and maladaptive signaling cascades that eventually lead to cardiac hypertrophy and heart failure. Among those, the mitogen-activated protein kinase (MAPK) signaling pathway has been shown to play a prominent role. The dual specificity phosphatases (DUSPs), also known as MAPK specific phosphatases (MKPs), that can dephosphorylate the MAPKs and inactivate them are gaining increasing attention as potential drug targets. Here we try to review recent advancements in understanding the roles of the different DUSPs, and the pathways that they regulate in cardiac remodeling. We focus on the regulation of three main MAPK branches – the p38 kinases, the c-Jun-N-terminal kinases (JNKs) and the extracellular signal-regulated kinases (ERK) by various DUSPs and try to examine their roles.     

万寿菊再生体系的建立及优化

以40个不同基因型万寿菊(Tagetes erecta)叶片为外植体, 在相同条件下诱导不定芽分化, 获得最佳再生基因型; 然后分析不同激素组合、外植体切口方式、固化剂及蔗糖对万寿菊再生和玻璃化影响; 最后对不同类型的伸长培养基进行探索。结果表明, 最佳再生基因型为里程碑·黄色; 最佳再生培养基为MS+0.2 mg·L^‒1 TDZ+0.5 mg·L^‒1 IBA+8 g·L^‒1琼脂+40 g·L^‒1蔗糖, 再生率达70%, 玻璃化率降低至16%; 最适再生的小叶部位为全小叶; 最适伸长培养基为MS+8 g·L^‒1琼脂+30 g·L^‒1蔗糖, 伸长率达91.3%。该研究建立了高效稳定的万寿菊再生体系, 解决了万寿菊再生过程中严重的玻璃化问题, 可为万寿菊的遗传改良和基因功能研究奠定基础。     

The Establishment and Optimization of a Regeneration System for Marigold (Tagetes erecta)

以40个不同基因型万寿菊(Tagetes erecta)叶片为外植体, 在相同条件下诱导不定芽分化, 获得最佳再生基因型; 然后分析不同激素组合、外植体切口方式、固化剂及蔗糖对万寿菊再生和玻璃化影响; 最后对不同类型的伸长培养基进行探索。结果表明, 最佳再生基因型为里程碑·黄色; 最佳再生培养基为MS+0.2 mg·L^?1 TDZ+0.5 mg·L^?1 IBA+8 g·L^?1琼脂+40 g·L^?1蔗糖, 再生率达70%, 玻璃化率降低至16%; 最适再生的小叶部位为全小叶; 最适伸长培养基为MS+8 g·L^?1琼脂+30 g·L^?1蔗糖, 伸长率达91.3%。该研究建立了高效稳定的万寿菊再生体系, 解决了万寿菊再生过程中严重的玻璃化问题, 可为万寿菊的遗传改良和基因功能研究奠定基础。     

Regeneration of the visual system in gastropods (Mollusca)

Abstract. The topic of tissue and organ regeneration has been of interest to life scientists ever since the phenomenon was noticed. The reason for this is obvious: if one can learn what drives and controls regeneration, i.e., how lost or damaged structures can be replaced, one not only has a better chance to understand an animal's embryogenesis and evolutionary relationship with other taxa, but one would also be in a better position to treat organ loss or tissue damage in humans. In this context, the possible restitution of individual sensory neurons or nerve projections has been of special interest to us. We identified central visual projections in several gastropod species and found that: (1) projections are very extensive across the brain and (2) they have connections with other systems and organs (including, most likely, non-ocular skin photoreceptors) that may be involved in the integration of signals from different sensors. Investigations of afferent and efferent visual elements at a morphological level should help reveal the neuronal basis of a gastropod's behavioral reactions.     

Gibson's reclassification of the enoplan nemerteans (Enopla, Nemertea): a critique and cladistic analysis

Gibson's (1988) reclassification of the class Enopla (phylum Nemertea), and in particular the forming of the taxon Paramonostilifera, is assessed by a cladistic analysis based on 35 characters. This analysis does not support the reclassification, and it is suggested that the previous classification is kept for the time being, although it is recognized that certain of the higher categories are non-monophyletic and should be reclassified.     

南瓜属植物再生体系的建立及其应用

对南瓜属植物再生体系的研究及其应用作了介绍,并对存在问题和改进措施进行了分析讨论。     

Bilateral uric acid nephrolithiasis and ureteral hypertrophy in a free-ranging river otter (Lontra canadensis)

We report the first case of uric acid nephrolithiasis in a free-ranging river otter (Lontra canadensis). A 7 yr old male river otter collected from the Skagit River of western Washington (USA) had bilateral nephrolithiasis and severely enlarged ureters (one of 305 examined [0.33%]). The uroliths were 97% uric acid and 3% protein. Microscopic changes in the kidney were confined to expansion of renal calyces, minor loss of medullary tissue, and multifocal atrophy of the cortical tubules. No inflammation was observed in either kidney or the ureters. The ureters were enlarged due to marked hypertrophy of smooth muscle plus dilation of the lumen. Fusion of the major calyces into a single ureteral lumen was several cm distal to that of two adult male otters used as histopathologic control specimens. This case report is part of a large contaminant study of river otters collected from Oregon and Washington. It is important to understand diseases and lesions of the otter as part of our overall evaluation of this population.     

Regeneration in youngBunodactis verrucosa Pennant (actinaria,anthozoa)

Summary YoungBunodactis verrucosa Pennant at the 12 tentacle stage are employed to test the applicability of the polar coordinate model to coelenterate regeneration. The animals are cut along every radius into fragments of 3 to 9 segments. Most fragments are patent 3–4 weeks later, but small fragments have a higher mortality rate than large fragments. Some fragments do not regenerate and occasionally tentacles fuse, thereby reducing the number of segments. Small fragments tend to regenerate more tentacies than large fragments, but large fragments may regenerate great numbers of supernumerary tentacles. Twenty-two percent of the fragments restore the missing number of tentacles, while 76% of all fragments produce an even number of tentacles.Fragments restoring the correct numbers of tentacles show a marked tendency to form the correct tentacles (regulative regeneration). Fragments regenerating two less than the number of tentacles already present show a marked tendency to reproduce tentacles of the types already present (miror image formation). Other fragments produce missing segments (forward regeneration), or those already present (reverse regeneration) at lower frequencies.No fragments beginning or ending with the number 1 directive tentacle fail to regenerate entirely, while first cycle segments maximally remote from segment 1 are associated with the absence of regeneration. No fragments beginning or ending with the number 4 directive tentacle fail to undergo forward regeneration, regulate or produce a mirror image when the appropriate number of segments are regenerated. In contrast, segment 4 is associated with a low frequency of reverse regeneration, and second cycle segments cut away from immediate contact with segment 4 show an increase in the frequency of reverse regeneration. Controls through morphogenic substances rather than polar coordinates seem to explain these results. Such substances would control the number and direction of tentacle regeneration.This work was performed while the author was on sabbatical leave from the University of Pittsburgh at the Stazione Zoologica di Napoli. The author gratefully acknowledges the assistance of Mr. Ciro Gargiulo and of Ms. Gisella Princivalli. This work was supported by a travel grant from the United States Italy Cooperative Science Program of the National Science Foundation. The paper is dedicated to Dr. Alberto Monroy whose generosity made it possible