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1.
Surfactant protein-A (SP-A) belongs to a family of collagen-containing C-type lectins called collectins. SP-A is expressed by renal tubule epithelial cells. We investigated the distribution of SP-A in renal cell carcinomas (RCC) using immunohistochemical techniques and western blotting. We used 35 formalin fixed, paraffin embedded (FFPE) RCC tissue samples. We compared results with clinico-pathological parameters of RCC including age, sex, Fuhrman grade, tumor volume, tumor node metastasis (TNM) and clinical stage. SP-A was localized in the glomerulus and renal tubule epithelium in nontumor tissue and strong SP-A immunoreactivity was observed in tumor tissue. SP-A was expressed in the RCC tumor cells (64%) and nontumor cells (34%) in males and RCC tumor cells (90%) and nontumor cells (30%) in females. There was a significant correlation between SP-A immunoreactivity in tumor cells and gender, age, tumor diameter, Fuhrman grade and tumor diameter. Western blot analysis supported the immunohistochemical findings. We present evidence for involvement of SP-A in RCC and suggest that increased SP-A expression in RCC is associated with favorable prognosis. 相似文献
2.
In a three-hour bioassay, we tested the palatability and feeding preferences of Uresiphita maorialis (kōwhai moth) for Sophora tetraptera, Sophora microphylla and Sophora prostrata. Palatability tests showed no differences among the Sophora species. Feeding preferences, on the other hand, showed that S. tetraptera and S. microphylla leaves are preferred over S. prostrata leaves. Our results support our field observations in Wellington city parks and gardens showing that S. tetraptera and S. microphylla plants frequently have higher densities of larvae than S. prostrata. 相似文献
3.
EC Costa A Moreira B Cavalcanti K Krinski MS Aoki 《Biology of sport / Institute of Sport》2015,32(1):35-40
The present study investigated the effect of unilateral and bilateral resistance exercise (RE) on maximal voluntary strength, total volume of load lifted (TVLL), rating of perceived exertion (RPE) and blood lactate concentration of resistance-trained males. Twelve healthy men were assessed for the leg extension one-repetition maximum (1RM) strength using bilateral and unilateral contractions. Following this assessment, an RE session (3 sets of repetitions to failure) was conducted with bilateral and unilateral (both limbs) contractions using a load of 50% 1RM. The TVLL was calculated by the product of the number of repetitions and the load lifted per repetition. RPE and blood lactate were measured before, during and after each set. Session RPE was measured 30 minutes after RE sessions. There was a significant difference in the bilateral (120.0±11.9) and unilateral (135.0±20.2 kg) 1RM strength (p < 0.05). The TVLL was similar between both RE sessions. Although the repetitions decreased with each successive set, the total number of repetitions completed in the bilateral protocol (48) was superior to the unilateral (40) protocol (p < 0.05). In both bouts, RPE increased with each subsequent set whilst blood lactate increased after set 1 and thereafter remained stable (p < 0.05). The RPE and lactate responses were not significantly different between both sessions. In conclusion, a bilateral deficit in leg extension strength was confirmed, but the TVLL was similar between both RE sessions when exercising to voluntary fatigue. This outcome could be attributed to the number of repetitions completed in the unilateral RE bout. The equal TVLL would also explain the similar perceptual and metabolic responses across each RE session. 相似文献
4.
Chronic cocaine and withdrawal induce significant alterations in nucleus accumbens (NAc) glutamatergic function in humans and rodent models of cocaine addiction. Dysregulation of glutamatergic function of the prefrontal cortical-NAc pathway has been proposed as a critical substrate for unmanageable drug seeking. Previously, we demonstrated significant up-regulation of NMDA, (+/-)-alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) and kainate receptor subunit mRNAs and protein levels in the ventral tegmental area (VTA), but not the substantia nigra, of cocaine overdose victims (COD). The present study was undertaken to examine the extent of altered ionotropic glutamate receptor (iGluR) subunit expression in the NAc and the putamen in cocaine overdose victims. Results revealed statistically significant increases in the NAc, but not in the putamen, of NMDA receptor subunit (NR)1 and glutamate receptor subunit (GluR)2/3 wit trends in GluR1 and GluR5 in COD. These results extend our previous finding and indicate pathway-specific alterations in iGluRs in COD. In order to determine that changes were related to cocaine intake and not to other factors in the COD victims, we examined the effects of cocaine intravenous self-administration in rhesus monkeys for 18 months (unit dose of 0.1 mg/kg/injection and daily drug intake of 0.5 mg/kg/session). Total drug intake for the group of four monkeys was 37.9 +/- 4.6 mg/kg. Statistically significant elevations were observed for NR1, GluR1, GluR2/3 and GluR5 (p < 0.05) and a trend towards increased NR1 phosphorylated at serine 896 (p = 0.07) in the NAc but not putamen of monkeys self-administering cocaine compared with controls. These results extend previous results by demonstrating an up-regulation of NR1, GluR2/3 and GluR5 in the NAc and suggest these alterations are pathway specific. Furthermore, these changes may mediate persistent drug intake and craving in the human cocaine abuser. 相似文献
5.
三氧化二砷对食管癌细胞增殖和热休克蛋白70表达的影响 总被引:2,自引:0,他引:2
目的:研究三氧化二砷(As2O3)对食管癌细胞增殖和热休克蛋白70(HSP70)表达的影响。方法:通过相差显微镜、流式细胞术、免疫细胞化学染色和免疫印迹分析等方法观察As2O3对人食管癌细胞株EC1的作用效果和作用机制。结果:与对照组相比,经2μmol/L和5μmol/Las2O3作用的细胞出现明显的生长抑制,G2/M期细胞比例增加;2μmol/Las2O3作用48h后经Ecl细胞HSP70(heat shock protein70)及HSC70(heat shock cognate protein70)表达均增加。结论:As2O3诱导食管癌细胞G2/M期阻滞抑制细胞增殖和生长;HSP70的升高是细胞对As2O3作用后出现的应激反应,并与细胞周期阻滞相关。 相似文献
6.
Thomas GH; Newbern EC; Korte CC; Bales MA; Muse SV; Clark AG; Kiehart DP 《Molecular biology and evolution》1997,14(12):1285-1295
Many structural, signaling, and adhesion molecules contain tandemly
repeated amino acid motifs. The alpha-actinin/spectrin/dystrophin
superfamily of F-actin-crosslinking proteins contains an array of triple
alpha-helical motifs (spectrin repeats). We present here the complete
sequence of the novel beta-spectrin isoform beta(Heavy)- spectrin (beta H).
The sequence of beta H supports the origin of alpha- and beta-spectrins
from a common ancestor, and we present a novel model for the origin of the
spectrins from a homodimeric actin-crosslinking precursor. The pattern of
similarity between the spectrin repeat units indicates that they have
evolved by a series of nested, nonuniform duplications. Furthermore, the
spectrins and dystrophins clearly have common ancestry, yet the repeat unit
is of a different length in each family. Together, these observations
suggest a dynamic period of increase in repeat number accompanied by
homogenization within each array by concerted evolution. However, today,
there is greater similarity of homologous repeats between species than
there is across repeats within species, suggesting that concerted evolution
ceased some time before the arthropod/vertebrate split. We propose a
two-phase model for the evolution of the spectrin repeat arrays in which an
initial phase of concerted evolution is subsequently retarded as each new
protein becomes constrained to a specific length and the repeats diverge at
the DNA level. This evolutionary model has general applicability to the
origins of the many other proteins that have tandemly repeated motifs.
相似文献
7.
8.
Introduction
Laser Doppler imaging (LDI) is a relatively new method for assessing the functional aspect of superficial skin blood flow in systemic sclerosis (SSc) and Raynaud's phenomenon. The present study investigated the dynamic behavior of digital skin microvascular blood flow before and after cold stimulus (CS) in SSc patients and in healthy controls by means of a comprehensive approach of the functional (LDI), morphological (nailfold capillaroscopy (NFC)), and biochemical (fingertip lacticemy (FTL)) microcirculation components. 相似文献9.
Understanding how autocrine/paracrine factors regulate neural stem cell (NSC) survival and growth is fundamental to the utilization of these cells for therapeutic applications and as cellular models for the brain. In vitro, NSCs can be propagated along with neural progenitors (NPs) as neurospheres (nsphs). The nsph conditioned medium (nsph-CM) contains cell-secreted factors that can regulate NSC behavior. However, the identity and exact function of these factors within the nsph-CM has remained elusive. We analyzed the nsph-CM by mass spectrometry and identified DSD-1-proteoglycan, a chondroitin sulfate proteoglycan (CSPG), apolipoprotein E (ApoE) and cystatin C as components of the nsph-CM. Using clonal assays we show that CSPG and ApoE are responsible for the ability of the nsph-CM to stimulate nsph formation whereas cystatin C is not involved. Clonal nsphs generated in the presence of CSPG show more than four-fold increase in NSCs. Thus CSPG specifically enhances the survival of NSCs. CSPG also stimulates the survival of embryonic stem cell (ESC)-derived NSCs, and thus may be involved in the developmental transition of ESCs to NSCs. In addition to its role in NSC survival, CSPG maintains the three dimensional structure of nsphs. Lastly, CSPG's effects on NSC survival may be mediated by enhanced signaling via EGFR, JAK/STAT3 and PI3K/Akt pathways. 相似文献
10.
Mitochondrial DNA and bindin gene sequence evolution among allopatric species of the sea urchin genus Arbacia 总被引:3,自引:1,他引:2
Sea urchins of the genus Arbacia (order Stirodonta) have discontinuous
allopatric distributions ranging over thousands of kilometers.
Mitochondrial DNA (mtDNA) sequences were used to reconstruct phylogenetic
relationships of four Arbacia species and their geographic populations.
There is little evidence of genetic structuring of populations within
species, except in two cases at range extremes. The mtDNA sequence
differentiation between species suggests that divergence occurred about 4-9
MYA. Gene sequences encoding the sperm protein bindin and its intron were
obtained and compared with the mtDNA phylogeny. Sea urchins among the
well-studied echinoid order Camarodonta, with degrees of mtDNA divergence
similar to those of Arbacia species, are known to have remarkable variation
in bindin. However, in Arbacia, little variation in deduced amino acid
sequences of bindin was found, indicating that purifying selection acts on
the protein. In contrast, bindin intron sequences showed much
differentiation, including numerous insertion/deletions. Fertilization
experiments performed between a divergent pair of Arbacia species from the
Atlantic and Pacific Oceans revealed no evidence of blocks to gamete
recognition. In Arbacia, fertilization specificities may have evolved
relatively slowly as a result of extensive gene flow within species,
greater functional constraint on the bindin polypeptide, or reduced
selective pressure for species recognition in singly occurring species.
相似文献