MACC1 Down-Regulation Inhibits Proliferation and Tumourigenicity of Nasopharyngeal Carcinoma Cells through Akt/β-Catenin Signaling Pathway

The present study was aimed at investigating the expression of metastasis-associated in colon cancer 1 (MACC1) in nasopharyngeal carcinoma (NPC), its relationship with β-catenin, Met expression and the clinicopathological features of NPC, and its roles in carcinogenesis of NPC. Our results showed that MACC1 expression was higher in NPC cells and tissues than that in normal nasopharyngeal cells and chronic inflammation of the nasopharynx tissues, respectively. MACC1 expression was closely related to the clinical stage (p = 0.005) and the N classification (p<0.05) of NPC. Significant correlations between MACC1 expression and Met expression (p = 0.003), MACC1 expression and β-catenin abnormal expression (p = 0.033) were found in NPC tissues. MACC1 knockdown dramatically inhibited cellular proliferation, migration, invasion, and colony formation, but induced apoptosis in NPC cells compared with the control group. Furthermore, MACC1 down-regulation inhibited phosphorylated-Akt (Ser473) and β-catenin expression in NPC cells, but phosphorylated-Erk1/2 expression was not altered. Further study showed that phosphotidylinsitol-3-kinase inhibitor downregulated β-catenin and Met expression in NPC cells. There was a significant relationship between MACC1 expression and phosphorylated-Akt expression (p = 0.03), β-catenin abnormal expression and phosphorylated-Akt expression (p = 0.012) in NPC tissue, respectively. In addition, Epstein Barr virus-encoded oncogene latent membrane protein 1 upregulated MACC1 expression in NPC cells. Our results firstly suggest that MACC1 plays an important role in carcinogenesis of NPC through Akt/β-catenin signaling pathway. Targeting MACC1 may be a novel therapeutic strategy for NPC.     

Complete nucleotide sequence and organization of the mitogenome of the silk moth Caligula boisduvalii (Lepidoptera: Saturniidae) and comparison with other lepidopteran insects

The 15,360-bp long complete mitogenome of Caligula boisduvalii possesses a gene arrangement and content identical to other completely sequenced lepidopteran mitogenomes, but different from the common arrangement found in most insect order, as the result of the movement of tRNA(Met) to a position 5'-upstream of tRNA Ile. The 330-bp A+T-rich region is apparently capable of forming a stem-and-loop structure, which harbors the conserved flanking sequences at both ends. Dissimilar to what has been seen in other sequenced lepidopteran insects, the initiation codon for C. boisduvalii COI appears to be TTG, which is a rare, but apparently possible initiation codon. The ATP8, ATP6, ND4L, and ND6 genes, which neighbor another PCG at their 3' end, all harbored potential sequences for the formation of a hairpin structure. This is suggestive of the importance of such structures for the precise cleavage of the mRNA of mature PCGs. Phylogenetic analyses of available sequenced species of Bombycoidea, Pyraloidea, and Tortricidea supported the morphology-based current hypothesis that Bombycoidea and Pyraloidea are monophyletic (Obtectomera). As previously suggested, Bombycidae (Bombyx mori and B. mandarina) and Saturniidae (Antheraea pernyi and C. boisduvalii) formed a reciprocal monophyletic group.     

Electron paramagnetic and electron nuclear double resonance of the hydrogen peroxide compound of cytochrome c peroxidase

We have collected electron paramagnetic resonance (EPR) and electron nuclear double resonance (ENDOR) spectra from the hydrogen peroxide compound of yeast cytochrome c peroxidase, termed ES, employing EPR microwave frequencies of 9.6 and 11.6 GHz. We have measured and analyzed the temperature dependence of the spin-lattice relaxation rate (1/T1) of the paramagnetic center of ES over the temperature range 1.9 to 4 K. In addition, an upper bound to exchange coupling between the ferryl heme and EPR-visible centers of ES has been calculated and expressions for the dipolar interaction between a ferryl heme and a free radical have been derived. These results all confirm that the EPR signal of ES is not associated with an aromatic amino acid radical, and in particular not with a tryptophanyl radical. This conclusion has led us to consider an explanation of the EPR signal in terms of a nucleophilically stabilized methionyl radical.     

Removing environmental organic pollutants with bioremediation and phytoremediation

Hazardous organic pollutants represent a threat to human, animal, and environmental health. If left unmanaged, these pollutants could cause concern. Many researchers have stepped up efforts to find more sustainable and cost-effective alternatives to using hazardous chemicals and treatments to remove existing harmful pollutants. Environmental biotechnology, such as bioremediation and phytoremediation, is a promising field that utilizes natural resources including microbes and plants to eliminate toxic organic contaminants. This technology offers an attractive alternative to other conventional remediation processes because of its relatively low cost and environmentally-friendly method. This review discusses current biological technologies for the removal of organic contaminants, including chlorinated hydrocarbons, focusing on their limitation and recent efforts to correct the drawbacks.     

Chimeric contribution of human extended pluripotent stem cells to monkey embryos ex vivo

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Carbon accumulation and distribution in Pinus massoniana and Cunninghamia lanceolata mixed forest ecosystem in Daqingshan, Guangxi, China

Carbon accumulation and distribution were studied at three sampling plots in a 13-year-old mixed planatation of Pinus massoniana and Cunninghamia lanceolata in Daqingshan, Guangxi, China. The results showed that carbon content varied with tissues and tree species, but the total carbon content of Pinus massoniana was higher than that of Cunninghamia lanceolata. The average tissue carbon contents of Pinus massoniana were: wood (58.6%) > root (56.3%) > branch (51.2%) > bark (49.8%) > leaf (46.8%), while those of Cunninghamia lanceolata were: bark (52.2%) > leaf (51.8%) > wood (50.2%) > root (47.5%) > branch (46.7%). The carbon contents of the soil (at a depth of 60cm) ranged from 1.45% to 1.84% with an average of 1.70%. Carbon contents were higher in the surface soil (0–20cm) than in the deep layer (below 20cm). The average carbon contents were the highest for trees (51.1%), followed by litter (48.3%), shrubs (44.1%), and herbs (33.0%). The biomass of the trees in the three plots ranged from 85.35 t hm^-2 to 101.35 t hm^-2 with an average of 93.83 t hm^-2, in which 75.7%–82.6% was Pinus massoniana. The biomass of the understory was 2.10–3.95 t hm^-2 with an average of 2.72 t hm^-2, while the standing stock of ground litter was 5.49–7.91 t hm^-2 with an average of 6.75 t hm^-2. The carbon storage in the mixed plantation reached the maximum in the soil layer (69.02%), followed by vegetation (29.03%), and standing litter (1.82%). The carbon storage in the tree layer occupied 23.90% of the total ecosystem and 97.7% of the vegetation layer. Pinus massoniana accounted for 65.39% of the total carbon storage in the tree layer. Tissue carbon storage was directly related to the corresponding amount of biomass. Trunks had the highest carbon storage, accounting for 53.23% of the trees in Pinus massoniana and 55.57% in Cunninghamia lanceolata, respectively. Roots accounted for about 19.22% of the total tree carbon. The annual net productivity of the mixed plantation was 11.46 t hm^-2a^-1, and that of sequestered carbon was 5.96 t hm^-2a^-1, which was equivalent to fixing CO₂ of 21.88 t hm^-2a^-1. The plantation was found to be an important sink of atmospheric CO₂.     

MRI Features in a Canine Model of Ischemic Stroke: Correlation between Lesion Volume and Neurobehavioral Status during the Subacute Stage

The purpose of this study was to evaluate the diagnostic value of magnetic resonance imaging (MRI) and assess the correlation between the volume of the ischemic lesion and neurobehavioral status during the subacute stage of ischemic stroke. Ischemic stroke was induced in 6 healthy laboratory beagles through permanent occlusion of the middle cerebral artery (MCAO). T2-weighted and fluid-attenuated inversion recovery (FLAIR) imaging, diffusion-weighted imaging (DWI), measurement of the apparent diffusion coefficient (ADC) ratio, and neurobehavioral evaluation were performed 3 times serially by using a 1.5-T MR system: before and 3 and 10 d after MCAO. Ischemic lesions demonstrated T2 hyperintensity, FLAIR hyperintensity, and DWI hyperintensity. The ADC ratio was decreased initially but then was increased at 10 d after MCAO. Ischemic lesion volumes on T2-weighted and FLAIR imaging were not significantly different from those on DWI. The lesion volume and neurobehavioral score showed strong correlation. Our results suggest that conventional MRI may be a reliable diagnostic tool during the subacute stage of canine ischemic stroke.Abbreviations: ADC, apparent diffusion coefficient; DWI, diffusion-weighted imaging; FLAIR, fluid-attenuated inversion recovery; MCAO, middle cerebral artery occlusion; MRI, magnetic resonance imaging; PWI, perfusion-weighted imagingIn human medicine, stroke is a leading cause of adult mortality and neurologic disability worldwide.¹ Strokes previously were thought to be uncommon in small animals, but the true prevalence is unknown.⁴ These events are now recognized more frequently in dogs because of increased use of magnetic resonance imaging (MRI).^5,14,17Because the infusion of thrombolytic agents, such as urokinase or tissue plasminogen activator, within 3 to 6 h of the onset symptoms is effective in restoring blood flow and improving stroke outcome in humans,¹⁹ the detection of early ischemic changes is now thought to be necessary to improve patient outcome. Computed tomography and conventional MRI are not sufficiently sensitive to predict the presence and extent of ischemic damage during the acute stage after a stroke.^12,20 Therefore several MRI sequences, such as fluid-attenuated inversion recovery (FLAIR), diffusion-weighted imaging (DWI), perfusion-weighted imaging (PWI), and MR angiography, have been developed for early diagnosis and subsequent follow-up of ischemic stroke.³ High-field magnetic strengths (at least 1.5 T) are necessary to perform these sequences.In contrast to the situation in humans, ischemic stroke in many dogs is diagnosed during the subacute stage—24 h to 6 wk after the vascular insult—due to the time lag between the onset of clinical signs to referral and to the lack of standard diagnostic protocols for ischemic stroke in dogs. In most reports of strokes in dogs, the median interval between the onset of neurologic dysfunction and performance of an MRI was more than 2 d.^5,14,17 Whereas DWI has marked sensitivity to very early ischemic changes in the brain, T2-weighted and FLAIR images gradually become more hyperintense later (that is, during the first 24 h after the insult).³ Therefore, hyperintensity on T2-weighted and FLAIR images is believed to be representative of mature lesions.¹⁵ In light of these findings, we hypothesized that conventional MR sequences, such as T2-weighted and FLAIR imaging as well as DWI would be used for the diagnosis of the subacute stage of ischemic stroke in dogs.The purpose of this study was to evaluate the diagnostic value of MRI and assess the correlation between the volume of ischemic lesions and neurobehavioral status during the subacute stage of ischemic stroke in dogs. We therefore investigated the lesion volume of T2-weighted and FLAIR images compared with that on DWI images. Furthermore, we assessed the relationship between the apparent diffusion coefficient (ADC) of the ischemic lesions and the neurobehavioral status of the dogs.