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281.
Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease with a complex etiology and pathology that makes the development of new therapies difficult. ACTH has neurotrophic and myotrophic effects, but has not been tested in an ALS mouse model. The G93A-SOD1 mouse model of ALS was used to test the ability of this drug to delay ALS-like symptoms. We showed that within a specific dose range, ACTH significantly postponed the disease onset and paralysis in the mouse model. To our surprise and of greater significance is that ACTH significantly reduced the levels of soluble SOD1 in the spinal cord and CNS tissues of G93A-SOD1 treated mice as well as cultured fibroblasts. 相似文献
282.
Arivalagan Sivaranjani Thomas Nisha Susan Chandrasekaran Balaji Mani Vijay Siddique Aktarul Islam Kuppsamy Thayalan Namasivayam Nalini 《Molecular and cellular biochemistry》2015,408(1-2):37-46
Molecular and Cellular Biochemistry - Colon cancer is one of the most commonly diagnosed cancers, and is a major cause of cancer morbidity and mortality worldwide. The objective of the present... 相似文献
283.
284.
We recently reported that bile salts play a role in the regulation of mucin
secretion by cultured dog gallbladder epithelial cells. In this study we
have examined whether bile salts also influence mucin secretion by the
human epithelial colon cell line LS174T. Solutions of bile salts were
applied to monolayers of LS174T cells. Mucin secretion was quantified by
measuring the secretion of [3H]GlcNAc labeled glycoproteins. Both
unconjugated bile salts as well as taurine conjugated bile salts stimulated
mucin secretion by the colon cells in a dose-dependent fashion. Hydrophobic
bile salts were more potent stimulators than hydrophilic bile salts. Free
(unconjugated) bile salts were more stimulatory compared with their taurine
conjugated counterparts. Stimulation of mucin secretion by LS174T cells was
found to occur at much lower bile salt concentrations than in the
experiments with the dog gallbladder epithelial cells. The protein kinase C
activators PMA and PDB had no stimulatory effect on mucin secretion. We
conclude that mucin secretion by the human colon epithelial cell line
LS174T is regulated by bile salts. We suggest that regulation of mucin
secretion by bile salts might be a common mechanism, by which different
epithelia protect themselves against the detergent action of bile salts, to
which they are exposed throughout the gastrointestinal tract.
相似文献
285.
286.
A codon-based model designed to describe lentiviral evolution 总被引:7,自引:6,他引:1
287.
Evolutionary relationships of human populations on a global scale 总被引:28,自引:2,他引:26
Using gene frequency data for 29 polymorphic loci (121 alleles), we
conducted a phylogenetic analysis of 26 representative populations from
around the world by using the neighbor-joining (NJ) method. We also
conducted a separate analysis of 15 populations by using data for 33
polymorphic loci. These analyses have shown that the first major split of
the phylogenetic tree separates Africans from non-Africans and that this
split occurs with a 100% bootstrap probability. The second split separates
Caucasian populations from all other non-African populations, and this
split is also supported by bootstrap tests. The third major split occurs
between Native American populations and the Greater Asians that include
East Asians (mongoloids), Pacific Islanders, and Australopapuans (native
Australians and Papua New Guineans), but Australopapuans are genetically
quite different from the rest of the Greater Asians. The second and third
levels of population splitting are quite different from those of the
phylogenetic tree obtained by Cavalli- Sforza et al. (1988), where
Caucasians, Northeast Asians, and Ameridians from the Northeurasian
supercluster and the rest of non- Africans form the Southeast Asian
supercluster. One of the major factors that caused the difference between
the two trees is that Cavalli-Sforza et al. used unweighted pair-group
method with arithmetic mean (UPGMA) in phylogenetic inference, whereas we
used the NJ method in which evolutionary rate is allowed to vary among
different populations. Bootstrap tests have shown that the UPGMA tree
receives poor statistical support whereas the NJ tree is well supported.
Implications that the phylogenetic tree obtained has on the current
controversy over the out-of-Africa and the multiregional theories of human
origins are discussed.
相似文献
288.
Mukhtar Tehmeena Ali Fawad Rafique Mazhar Ali Javed Afridi Muhammad Siddique Smith Donald Mehmood Shehzad Amna Souleimanov Alfred Jellani Ghulam Sultan Tariq Munis Farooq Hussain Chaudhary Hassan Javed 《Journal of Plant Growth Regulation》2023,42(1):523-538
Journal of Plant Growth Regulation - Endophytic microbes promote plant growth through various biochemical mechanisms and assist plants in resuming their morpho-physiological traits under abiotic... 相似文献
289.
290.
In the present investigation, a simple technique was employed to obtain cross-sections of unloaded and nifedipine loaded chitosan microspheres. Microspheres, adhering to a polymerized resin block, were cut with an ultramicrotome and viewed with a scanning electron microscope. Unloaded microspheres exhibited a uniform dense matrix structure while crystals of nifedipine were clearly visible in the drug-loaded microspheres. At 2% drug loading, however, no crystals could be seen in the microspheres indicating that either the drug was molecularly dispersed or dissolved in the matrix at this concentration. This was confirmed by powder X-ray diffractometry studies where no peak due to crystalline nifedipine was observed. At high Span 85 concentration (1.5% w/v), the external surface of the microspheres collapsed, but the internal structure remained dense. When the drug was dispersed in the chitosan solution with stirring during preparation, the entrapment was good and the shape of the crystals was changed. The internal structure of the microspheres following dissolution exhibited the presence of pores. 相似文献