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141.
Kumagai K Barinova AA Nakajima M Taniguchi N 《Marine biotechnology (New York, N.Y.)》2004,6(3):221-228
Threeline grunt (Parapristipoma trilineatum) distributes around the southwestern coast of Japan and the east coast of China. The Chinese P. trilineatum was imported by Japan as an aquacultural seed because of its rapid growth compared with that of the Japanese P. trilineatum. The Japanese P. trilineatum differs from the Chinese P. trilineatum in some quantitative traits, and it has been suggested that these two P. trilineatum populations are genetically different. In order to identify the population structures around Japan and China, 5 local populations of the Japanese P. trilineatum and 2 local populations of the Chinese P. trilineatum were analyzed using 4 microsatellite DNA markers. Significant differences were detected between Japanese and Chinese P. trilineatum and among samples of Chinese P. trilineatum; however, among the samples of Japanese P. trilineatum, no significant differences were detected. These results suggest that care must be taken to prevent the escape of the Chinese P. trilineatum from culture cages around the Japanese coast, in order to preserve the genetically different population structures of Japanese and Chinese P. trilineatum. 相似文献
142.
Franco SJ Rodgers MA Perrin BJ Han J Bennin DA Critchley DR Huttenlocher A 《Nature cell biology》2004,6(10):977-983
Dynamic regulation of adhesion complexes is required for cell migration and has therefore emerged as a key issue in the study of cell motility. Recent progress has been made in defining some of the molecular mechanisms by which adhesion disassembly is regulated, including the contributions of adhesion adaptor proteins and tyrosine kinases. However, little is known about the potential contribution of proteolytic mechanisms to the regulation of adhesion complex dynamics. Here, we show that proteolysis of talin by the intracellular calcium-dependent protease calpain is critical for focal adhesion disassembly. We have generated a single point mutation in talin that renders it resistant to proteolysis by calpain. Quantification of adhesion assembly and disassembly rates demonstrates that calpain-mediated talin proteolysis is a rate-limiting step during adhesion turnover. Furthermore, we demonstrate that disassembly of other adhesion components, including paxillin, vinculin and zyxin, is also dependent on the ability of calpain to cleave talin, suggesting a general role for talin proteolysis in regulating adhesion turnover. Together, these findings identify calpain-mediated proteolysis of talin as a mechanism by which adhesion dynamics are regulated. 相似文献
143.
The effect of cadmium on growth parameters of seedlings of maize, rye and wheat as well as the role of phytochelatins in Cd
detoxication in these species were studied. Cadmium was found to inhibit root growth and decrease fresh weight and water content
in roots and shoots of the studied plants. Although a considerably lower Cd accumulation was shown in maize seedlings than
in other species, they were characterized by the highest sensitivity to cadmium. Among γ-Glu-Cys peptides synthetized by plant
species, phytochelatins — glutathione derivatives predominated. In maize they were synthetized in amounts sufficient for binding
the total pool of the metal taken up, and the detoxication mechanism was localized in their roots. Larger amounts of cadmium
were accumulated in roots of wheat and rye, but the quantity of the formed γ-Glu-Cys peptides seems insufficient for detoxication
of the metal. 相似文献
144.
Anna N. Panek Maximilian G. Posch Natalia Alenina Santhosh K. Ghadge Bettina Erdmann Elena Popova Andreas Perrot Christian Geier Rainer Dietz Ingo Morano Michael Bader Cemil ?zcelik 《PloS one》2009,4(8)
Connective tissue growth factor (CTGF) is a secreted protein that is strongly induced in human and experimental heart failure. CTGF is said to be profibrotic; however, the precise function of CTGF is unclear. We generated transgenic mice and rats with cardiomyocyte-specific CTGF overexpression (CTGF-TG). To investigate CTGF as a fibrosis inducer, we performed morphological and gene expression analyses of CTGF-TG mice and rat hearts under basal conditions and after stimulation with angiotensin II (Ang II) or isoproterenol, respectively. Surprisingly, cardiac tissues of both models did not show increased fibrosis or enhanced gene expression of fibrotic markers. In contrast to controls, Ang II treated CTGF-TG mice displayed preserved cardiac function. However, CTGF-TG mice developed age-dependent cardiac dysfunction at the age of 7 months. CTGF related heart failure was associated with Akt and JNK activation, but not with the induction of natriuretic peptides. Furthermore, cardiomyocytes from CTGF-TG mice showed unaffected cellular contractility and an increased Ca2+ reuptake from sarcoplasmatic reticulum. In an ischemia/reperfusion model CTGF-TG hearts did not differ from controls.Our data suggest that CTGF itself does not induce cardiac fibrosis. Moreover, it is involved in hypertrophy induction and cellular remodeling depending on the cardiac stress stimulus. Our new transgenic animals are valuable models for reconsideration of CTGF''s profibrotic function in the heart. 相似文献
145.
146.
147.
Francesca Negri Gabriele Missale Anna Degli Antoni Camillo Porta 《Translational oncology》2021,14(9):101153
In the highly active antiretroviral therapy (HAART) era, hepatocellular carcinoma (HCC) is arising as a common late complication of human immunodeficiency virus (HIV) infection, with a great impact on morbidity and mortality. Though HIV infection alone may not be sufficient to promote hepatocarcinogenesis, the complex interaction of HIV with hepatitis is a main aspect influencing HCC morbidity and mortality.Data about sorafenib effectiveness and safety in HIV-infected patients are limited, particularly for patients who are on HAART. However, in properly selected subgroups, outcomes may be comparable to those of HIV-uninfected patients. Scarce data are available for those other systemic treatments, either tyrosine kinase inhibitors, as well as immune checkpoint inhibitors (ICIs), which have been added to our therapeutic armamentarium. This review examines the influence of HIV infection on HCC development and natural history, summarizes main data on systemic therapies, offers some insight into possible mechanisms of T cell exhaustion and reversal of HIV latency with ICIs and issues about clinical trials enrollment. Nowadays, routine exclusion of HIV-infected patients from clinical trial participation is totally inappropriate, since it leaves a number of patients deprived of life-prolonging therapies. 相似文献
148.
Hesham A. Agrama Anna M. McClung WenGui Yan 《Molecular breeding : new strategies in plant improvement》2012,29(2):413-425
Because of the rich diversity among rice accessions grown around the world in distinct environments, traditional methods using
morphology, cross compatibility and geography for classifying rice accessions according to different sub-populations have
given way to use of molecular markers. Having a few robust markers that can quickly assign population structure to germplasm
will facilitate making more informed choices about genetic diversity within seedbanks and breeding genepools. WHICHLOCI is
a computer program that selects the best combination of loci for population assignment through empirical analysis of molecular
marker data. This program has been used in surveys of plant species, for fish population assignment, and in human ancestry
analysis. Using WHICHLOCI, we ranked the discriminatory power of 72 DNA markers used to genotype 1,604 accessions of the USDA
rice core collection, and developed panels with a minimum number of markers for population assignment with 99% or higher accuracy.
A total of 14 markers with high discriminatory power, genetic diversity, allelic frequency, and polymorphic information content
were identified. A panel of just four markers, RM551, RM11, RM224 and RM44, was effective in assigning germplasm accessions
to any of five sub-populations with 99.4% accuracy. Panels using only three markers were effective for assignment of rice
germplasm to specific sub-populations, tropical japonica,
temperate japonica,
indica, aus, and aromatic. Assignment to tropical japonica,
temperate japonica, or indica sub-populations was highly reliable using 3–4 markers, demonstrated by the high correlation with assignment using 72 markers.
However, population assignment to aus and aromatic groups was less reliable, possibly due to the smaller representation of this material in the USDA core collection. More reference
cultivars may be needed to improve population assignment to these two groups. This study demonstrated that a small number
of DNA markers is effective for classification of germplasm into five sub-populations in rice. This will facilitate rapid
screening of large rice germplasm banks for population assignment at a modest cost. The resulting information will be valuable
to researchers to verify population classification of germplasm prior to initiating genetic studies, maximizing genetic diversity
between sub-populations, or minimizing cross incompatibility while maximizing allelic diversity within specific sub-populations. 相似文献
149.
Abdullah Jaffer Brian Harvey Vivienne Ann Russell Machteld Elizabeth Carstens Anna Susanna de Villiers Joshua Joachim Fransua Taljaard 《Neurochemical research》1993,18(10):1057-1061
Chronic treatment of rats with lithium chloride was examined in order to determine its effect on hypothalamic monoamine and metabolite content, basal thyrotropin (TSH) secretion and thyroid function. The hypothalamic concentrations of noradrenaline (NA), dopamine (DA) and its metabolites, dihydroxyphenylacetic acid. (DOPAC) and homovanillic acid (HVA) in the lithium treated rats remained unaltered when compared to control levels. NA turnover and the NA metabolite, 3-methoxy-4-hydroxyphenylglycol (total MHPG), were significantly lower (p<0.01), whereas both serotonin (5-HT) and its metabolite, 5-hydroxyindole-3-acetic acid (5-HIAA), were significantly higher (p<0.01 and p<0.02, respectively) in the lithium treated rat hypothalami than in controls. Chronic lithium treatment significantly elevated basal TSH levels (p<0.05). This effect was antagonized by methylp-hydroxybenzoate (methylparaben, p<0.01), which did not itself affect basal TSH levels. Free serum T3 and T4 levels were not significantly affected by chronic lithium treatment, although T4 tended to be slightly lower than control levels. The monoamine changes observed in the hypothalamus of lithium treated rats did not appear to account for the elevated TSH levels observed in these rats since NA activity which is generally regarded as stimulatory was decreased and 5-HT which has an inhibitory effect on TSH secretion, was increased. The elevated TSH levels may have been due to a reduced negative feedback inhibition of TSH release by the mildly reduced circulating T4 levels caused by chronic lithium treatment. A further possibility is that the pituitary cGMP (and hence TSH) response to TRH may have been enhanced by chronic lithium treatment and methylparaben may have antagonized this effect. 相似文献
150.
Elzbieta Malarczyk Janina Kochmanska-Rdest Anna Jarosz-Wilkolazka 《Nonlinear biomedical physics》2009,3(1):1-8