Hepatocellular carcinoma (HCC) is one of the most common metastatic tumours. Tumour growth and metastasis depend on the induction of cell proliferation and migration by various mediators. Here, we report that the A Disintegrin and Metalloproteinase (ADAM) 8 is highly expressed in murine HCC tissues as well as in murine and human hepatoma cell lines Hepa1-6 and HepG2, respectively. To establish a dose-dependent role of different ADAM8 expression levels for HCC progression, ADAM8 expression was either reduced via shRNA- or siRNA-mediated knockdown or increased by using a retroviral overexpression vector. These two complementary approaches revealed that ADAM8 expression levels correlated positively with proliferation, clonogenicity, migration and matrix invasion and negatively with apoptosis of hepatoma cells. Furthermore, the analysis of pro-migratory and proliferative signalling pathways revealed that ADAM8 expression level was positively associated with expression of β1 integrin as well as with the activation of focal adhesion kinase (FAK), mitogen-activated protein kinase (MAPK), Src kinase and Rho A GTPase. Finally, up-regulation of promigatory signalling and cell migration was also seen with a proteolytically inactive ADAM8 mutant. These findings reveal that ADAM8 is critically up-regulated in hepatoma cells contributes to cell proliferation and survival and furthermore induces pro-migratory signalling pathways independently of its proteolytic activity. By this, ADAM8 can promote cell functions most relevant for HCC growth and metastasis. 相似文献
Thermal pyrolysis of mixed date stones and pistachio shells in a semi-batch reactor was addressed in this study. The highest yield of liquids (51.20 %) was produced at 500 °C, 90 min, 20 °C/min heating rate, and 50 mesh particle size. Under these conditions, yield of liquid from date stones and pistachio shells separately was 49.12 % and 47.67 %, respectively. The FT-IR results confirmed the presence of multiple oxygen-containing compounds in the bio-oil. Results from GC–MS declared that it was predominately composed of acids (57.57 %), esters (21.35 %), phenols (4.63 5), and alcohols (3.49 5). The obtained biochar was transformed into activated carbon (AC) by the optimized ZnCl2 activation method. The ideal AC was synthesized at 600 °C for 60 min using a 2 : 1 ZnCl2: biochar impregnation ratio. FESEM and XRD measurements showed that the AC was amorphous. The prepared AC was effective in eliminating dibenzothiophene (DBT) from model fuel (200 ppm DBT/hexane) with a maximum performance 95.26 % at 40 °C for 1h using 0.35 g of the AC. The exhausted AC was regenerated and reutilized 4 times, and removal efficiency reached 88.23 % in the 4th cycle under ideal working conditions. 相似文献
A series of poly(vinyl alcohol) of different commercial grades were prepared and applied onto the surfaces of cotton and blends of cotton/polyester fibers. The molecular structure was confirmed using Fourier Transform Infrared spectroscopy. Physicochemical properties such as viscosity and solid contents (%) were determined and discussed. Factors affecting the performance properties of the finished substrate such as post-treatment with poly(vinyl alcohol) of different grades, concentration and dilutions were studied. Fixation of the poly(vinyl alcohol) onto/or within the cellulose structure is accompanied by the formation of semi-inter-penetrated network structure thereby enhancing the association as well as providing very high stiffness. The results revealed that applications of poly(vinyl alcohol) on the textile fabrics in the finishing processes enables to enhance the stiffness as well as helps to improve its pilling resistance. 相似文献
The interactive effect of low P supply (0, 10, 20 and 40 M) and plant age on nodule number, mass and functioning (ureide analysis technique), vegetative growth and pod production were investigated in glasshouse-grown nodulated cowpea (Vigna unguiculata L.cv. Kausband) in sand culture. Compared with 40 M P, P stress (0 M P) or very low (10 M P) supply markedly impaired nodulation, allantoin and amino-N concentrations and weight of N solutes in xylem exudates. Consequently, P stress reduced top growth and pod yields by 48 and 90%, respectively. N solutes in xylem exudates and total plant N assayed by Kjeldahl technique (as estimates of N2 fixation) responded similarly to P supply. However, the relative ureide index [(ureide-N/ureide N+amino-N)×100] remained constant (99%), irrespective of P supply, indicating the plants' complete dependency on symbiosis for growth, without implying that growth was markedly increased by N2 fixation. Although P concentrations in plant tops, roots and nodules increased with P supply, N concentrations in these plant tissues were unaffected by P supply. The concentrations of N and P in the nodules were 2–2 1/2 times higher than in plant tops. P application interacted strongly with plant age, with the largest P effect evidently achieved at the early podding stage. The significance and implications of these results are discussed. 相似文献
Determination of the optimal inoculation method and concentration to use for plant-bacteria interaction studies is important in many cases, such as the phytoremediation of heavy metals and other toxic compounds in contaminated areas. The aim of this study was to compare different concentrations and times of inoculation of Pseudomonas putida with various growth stages of Arabidopsis thaliana in 14-d in vitro cultures. A significant beneficial impact of the bacterium was detected in the shoot length and root weight of seedlings. The highest shoot length and root fresh and dry weights were detected in 14-d and 2 × 103 cfu mL−1 inoculated samples. In addition, the increase in root weight could be visualized with crystal violet staining, as relatively more root hair and lateral root formation occurred in seedlings inoculated with moderate concentrations of bacteria, possibly due to the ability of P. putida to produce indole-acetic acid. Moreover, the highest photosynthetic pigment accumulation was obtained with the highest bacterial inoculum (2 × 106 cfu mL−1), which was tested in 0- or 3-d-old seedlings. Rhizospheric bacterial colonization was also visualized with GFP-labeled bacteria by confocal microscopy. These results showed that biotization of A. thaliana with P. putida KT2440 did not cause severe oxidative stress in seedlings, because H2O2 accumulation levels together with CAT and POX activities were not significantly induced. Therefore, this strain could be used for several applications based on plant-bacteria interactions.
The objective of this study was to determine the effect of oestrous synchronization methods on oestrous behaviour, timing of ovulation and pregnancy rate during the breeding and low breeding seasons in Nili-Ravi buffaloes. In Experiment 1, oestrous behaviour and timing of ovulation were determined from (n=34) oestruses. The mean (+/- S.E.M.) time of ovulation after the onset of standing oestrus was greater (P<0.05) in PGF(2alpha)-induced luteolysis (30.6+/-1.5h) compared to Ovsynch buffaloes (15.0+/-0.8h). In Experiment 2, pregnancy rates were compared between two methods of synchronization (detected oestrus and Ovsynch protocol) during the breeding and low breeding seasons. Pregnancy rates of buffaloes bred at detected oestrus (62.5%) or by the Ovsynch protocol (36.3%) during the breeding season did not differ significantly (P>0.05) from those which were inseminated during the low breeding season (55.5%) and (30.4%), respectively. This study demonstrates clearly that (1) timing of ovulation in Nili-Ravi buffalo is about 30h after the onset of standing oestrus and (2) buffaloes can be successfully synchronized with optimum fertility using either PGF(2alpha) alone (detected oestrus) or using (Ovsynch protocol) during low breeding season, to calve during the period when milk availability is short. 相似文献
The objective of this study was to characterize the follicular waves and associated ovarian events during spontaneous and PGF(2alpha)-induced oestrous cycles in Nili-Ravi buffaloes. In Exp. 1, (n=13 oestrous cycles) follicular and luteal development was monitored by ultrasonography and jugular blood samples were collected simultaneously on alternate days. Of 12 oestrous cycles, 9 (75%) had two waves of follicular activity and only 3 (25%) had three waves. The mean (+/-S.E.M.) length of the oestrous cycle was shorter (P<0.05) in buffaloes with two waves than in those with three waves (21.2+/-0.1 days versus 22.8+/-0.1 days). In Exp. 2, follicular dynamics were compared in buffaloes undergoing spontaneous (n=12 oestrous cycles) and PGF(2alpha)-induced (n=9) regression of the corpus luteum (CL). The dynamics of ovulatory follicular growth during the 3 days before oestrus were similar (P>0.05) in buffaloes undergoing spontaneous and PGF(2alpha)-induced luteolysis. These results show that (1) the majority of buffaloes had a two wave pattern of follicular growth and emergence of a third wave was associated with a longer luteal phase, and (2) follicular dynamics during the 3 days before oestrus were similar in buffaloes undergoing spontaneous and PGF(2alpha)-induced luteolysis. 相似文献