The functional role of P2 purinergic receptors in the progression of gastric cancer

Studies have confirmed that P2 purinergic receptors (P2X receptors and P2Y receptors) expressed in gastric cancer (GC) cells and GC tissues and correlates with their function. Endogenous nucleotides including ATP, ADP, UTP, and UDP, as P2 purinergic receptors activators, participate in P2 purinergic signal transduction pathway. These activated P2 purinergic receptors regulate the progression of GC mainly by mediating ion channels and intracellular signal cascades. It is worth noting that there is a difference in the expression of P2 purinergic receptors in GC, which may play different roles in the progression of GC as a tumor promoting factor or a tumor suppressor factor. Among them, P2 × 7, P2Y2 and P2Y6 receptors have certain clinical significance in patients with GC and may be used as biological molecular markers for the prediction of patients with GC. Therefore, in this paper, we discuss the functional role of nucleotide / P2 purinergic receptors signal axis in regulating the progression of GC and that these P2 purinergic receptors may be used as potential molecular targets for the prevention and treatment of GC.

ATP ion channel P2X7 receptor as a regulatory molecule in the progression of colorectal cancer

Large amounts of adenosine triphosphate (ATP), a natural P2X7 receptor activator, are released during colorectal carcinogenesis. P2X7 receptor activation regulates the activity of colorectal cancer (CRC) cells by mediating intracellular signal transduction. Importantly, the opening and activation of membrane pores of P2X7 receptor are different, which can play a dual role in promoting or inhibiting the progression of CRC. These can also depend on P2X7 receptor to regulate the activities of immune cells in the microenvironment, play the functions of immune regulation, immune escape and immune monitoring. While the use of P2X7 receptor antagonists (such as BBG, A438079 and A740003) can play a certain inhibitory pharmacological role on the activity of CRC. Therefore, in this paper, the mechanism and immunomodulatory function of P2X7 receptor involved in the progression of CRC were discussed. Moreover, we discussed the effect of antagonizing the activity of P2X7 receptor on the progression of CRC. So P2X7 receptor may be a new pharmacological molecular target for the treatment of CRC.

Acaricidal Activity of Cyclodipeptides from Bacillus amyloliquefaciens W1 against Tetranychus urticae

Bioassay-guided fractionation of the supernatant of the biocontrol strain Bacillus amyloliquefaciens W1 led to the isolation of eight acaricidal cyclodipeptides from the active fractions by column chromatography separation and HPLC purification. The chemical structures of these compounds were identified as cyclo-(Gly-l-Phe), 2, cyclo-(l-Phe- trans-4-OH-l-Pro), 3, cyclo-(Gly-l-Tyr), 4, cyclo-(l-Ala-l-Pro), 5, cyclo-(l-Pro- trans-4-OH-l-Pro), 6, cyclo-(Gly-l-Pro), 7, cyclo-(l-Pro-l-Pro), 8, and cyclo-(l-Tyr- trans-4-OH-l-Pro), 9. Those cyclodipeptides displayed significant acaricidal activities with LC₅₀ values of 13.85-98.24 μM. Cyclo-(l-Tyr- trans-4-OH-l-Pro) (LC₅₀ 13.85 μM) was five times more effective than the positive control abamectin (LC₅₀ 72.06 μM). The results indicated that the hydroxyl group is an important component. This is the first report on the acaricidal capabilities of cyclodipeptides against Tetranychus urticae. The results revealed that the acaricidal activity of the biocontrol strain B. amyloliquefaciens W1 was dependent on its constituent cyclodipeptides, which have the potential to be safe and environmentally friendly acaricides.

[A high-precision digital images date set of larynx]

Objective:To build a digital cross-sectional images date set of human normal larynx with high-precision.Method:A fresh frozen normal human larynx was embedded using Kawamot's Film Method and then serially sectioned at 10 μm with a LeicaCM3600XP Cryomacrotome, meanwhile digital images of the block surface were recorded after every section with a Nikon D750 camera and stored respectively as JPG and RAW files. All images were cropped to display a constant area on the block surface by photoshop7 and stored as TIFF files. Result:A total of 6 656 images were recorded in 24-bit RGB resolution, the complete data file is 97.5 GB and 174 GB. After elimination of image size variation, all images were re-sampled at a final resolution of 40 μm/pixel and the complete data file is 107 GB. Conclusion:It's feasible to use the combination of Kawamot's Film Method,Digital Single Lens Reflex with high-resolution and regular block face-based alignment to build high-precision digital images date set, which could apply to some partial organs that resemble larynx.

[The progress of 3D reconstruction of the larynx]

Larynx is a complicated organ of significant functions including breathing, voicing, protecting and so on, so it's important for anyone involved in the filed to know more about the multiple structures of the complex. Although there are numerous 2D images of larynx, it's still difficult for the observers to understand the organ well, so it's necessary to establish a real digital modal of larynx. With the development of computer and image processing technologies, medical imaging datasets have been used for the reconstruction of larynx. And the complete of visible human project also provides colorful cross-sectional images for reconstruction. The article reviews the development of the reconstruction of larynx, and predicts the possible developing direction of future 3D reconstruction.

[Advances in imaging evaluation of laryngeal carcinoma]

Laryngeal carcinoma is a common malignant tumor in the head and neck, and the squamous cell carcinoma of the larynx is the most prevelance. In view of the importance of laryngeal function and its survival, the choice of the best therapeutic regimen of laryngeal carcinoma must consider the potential survival rate and the change of postoperative function. The margin of laryngeal carcinoma is an important index of preoperative imaging evaluation of laryngeal carcinoma. The accurate determination of the cutting edge determines the operation mode, the success rate, the survival rate and prognosis of the patients with laryngeal carcinoma.In recent years, the method of preoperative evaluation of laryngeal tumors is diverse, including molecular, imaging and endoscopy, among which preoperative imaging is the most common method. The purpose of this study was to summarize the evaluation of different imaging techniques in the assessment of local invasion and recurrence of submucosal tumors in laryngeal carcinoma.

Osteogenic Treatment Initiating a Tissue-Engineered Cartilage Template Hypertrophic Transition

Hypertrophic chondrocytes play a critical role in endochondral bone formation as well as the progress of osteoarthritis (OA). An in vitro cartilage hypertrophy model can be used as a platform to study complex molecular mechanisms involved in these processes and screen new drugs for OA. To develop an in vitro cartilage hypertrophy model, we treated a tissue-engineered cartilage template, living hyaline cartilaginous graft (LhCG), with osteogenic medium for hypertrophic induction. In addition, endothelial progenitor cells (EPCs) were seeded onto LhCG constructs to mimic vascular invasion. The results showed that osteogenic treatment significantly inhibited the synthesis of endostatin in LhCG constructs and enhanced expression of hypertrophic marker-collagen type X (Col X) and osteogenic markers, as well as calcium deposition in vitro. Upon subcutaneous implantation, osteogenic medium-treated LhCG constructs all stained positive for Col X and showed significant calcium deposition and blood vessel invasion. Col X staining and calcium deposition were most obvious in osteogenic medium-treated only group, while there was no difference between EPC-seeded and non-seeded group. These results demonstrated that osteogenic treatment was of the primary factor to induce hypertrophic transition of LhCG constructs and this model may contribute to the establishment of an in vitro cartilage hypertrophy model.

Structure elucidation and antioxidant activity of a novel polysaccharide from Polyporus umbellatus sclerotia

A novel water-soluble polysaccharide PUP60S2, with a molecular weight of 1.44×10(4)Da, was obtained from the sclerotia of Polyporus umbellatus by hot water extraction, ethanol precipitation, anion-exchange and size-exclusion chromatography. PUP60S2 was a polysaccharide comprised of about 22.3% glucuronic acid. Monosaccharide composition analysis showed that PUP60S2 was only comprised of glucose and glucuronic acid. Reduction of carboxyl groups, sugar analysis, methylation analysis, together with one and two dimension NMR spectra disclosed that the backbone of PUP60S2 consisted of (1→6)-β-d-glucopyranosyl, every second of which was substituted at O-3 by side chains consisting of terminal β-d-Glcp, (1→3)-β-d-Glcp, (1→3)-β-d-GlcpA, (1→4)-β-d-Glcp and (1→4)-β-d-GlcpA units. The antioxidant activity assay in vitro showed that PUP60S2 exerted a significant scavenging effect on DPPH, hydroxyl radical and superoxide radical in a dose-dependent manner.

DCUN1D3, a novel UVC-responsive gene that is involved in cell cycle progression and cell growth

DCUN1D3 (DCN1, defective in cullin neddylation 1, domain containing 3) was found during the process of high throughput screening of novel human genes associated with serum response element (SRE) pathway activation. The DCUN1D3 gene is highly conserved among vertebrates. Human DCUN1D3 complementary DNA (cDNA) encodes 304 amino acids with an apparent molecular mass of 34 kDa. However, there has been no report about the function of DCUN1D3. This study detected that DCUN1D3 was broadly expressed in several tumor tissues and cultured cell lines; however, UVC irradiation of different doses significantly increased DCUN1D3 expression level in these cancer cell lines. Over-expression of the DCUN1D3 inhibits cell growth in HeLa. When the DCUN1D3 gene was silenced by siRNA in UVC-treated HeLa, the cell cycle in S phase was remarkably blocked; furthermore, the UVC-induced cell death was inhibited. In addition, DCUN1D3 localized mainly in the cytoplasm and perinuclear, but after UVC treatment, the DCUN1D3 gradually entered the nucleus. All the results above indicate that DCUN1D3 is a novel UVC-response gene involved in cell cycle regulation and cell survival.

Heterogeneity of angiotensin type 2 (AT2) receptors

Evidence continues to accumulate that strengthens the proposal of heterogeneity within both the AT1 and the AT2 receptor subtypes. Pharmacologic, biochemical and immunological studies of AT2 receptors expressed in N1E-115 cells strengthen the hypothesis of AT2 receptor heterogeneity. However, it is important to reassess these studies, especially in terms of how these results correlate with other reports of AT2 receptor heterogeneity. For example, AT2 receptor immunoreactivity was absent in some neuronal regions which have previously been proposed to express the AT2 receptor subtype. In particular, AT2 receptor staining was not seen in the inferior olive, a region which is known to express a high density of AT2 receptors. Upon first examination, these results were somewhat troubling. However, when compared with earlier reports, these results should not have been unexpected. For instance, Tsutsumi and Saaverdra previously have shown that AT2 receptors in the locus coeruleus are sensitive to the actions of guanine nucleotides, while AT2 receptors in the inferior olive are insensitive (21). These antisera were raised against a population of AT2 receptors which are sensitive to GTP gamma S and therefore, the lack of AT2 receptor staining in the inferior olive, as well as the presence of AT2 receptor immunoreactivity in the locus coeruleus, confirms and extends these earlier reports. In addition the AT2 receptors expressed in the locus coeruleus have been shown to be functionally distinct from AT2 receptors in the inferior olive. In this regard, Ang II has been shown to depress glutamate-induced EPSPs in the locus coeruleus, an effect which is mediated through the AT2 receptor (19). Conversely, AT2 receptors have been shown to increase the firing rate of neurons in the inferior olive (20). Collectively, these results would predict that staining should be absent in the inferior olive using these AT2-directed antisera. Indeed, in view of these earlier physiological and pharmacological studies, the presence of AT2 receptor immunoreactivity in the inferior olive would have been surprising. The most convincing example of AT2 receptor heterogeneity is the characterization of AT2 receptors present in N1E-115 cells. Separation of solubilized N1E-115 membranes by heparin-Sepharose chromatography generates two populations of AT2 receptors which are pharmacologically and biochemically distinct. In particular, CGP42112A was approximately 2 orders of magnitude more selective for Peak III AT2 receptors than was PD123319. Binding activity of Peak I and Peak III AT2 receptor populations also differed in their responses to GTP gamma S and DTT treatment. Lastly, the AT2-directed antisera, raised against the Peak I population of AT2 receptors, were not able to immunodetect the Peak III population of AT2 receptors in immunoblot analysis, or immunoprecipiatate AT2 binding activity from Peak III material. Pharmacological, biochemical and immunological analysis of the AT2 receptor clone isolated from N1E-115 cells revealed that it has the identical characteristics or properties of the Peak III receptor. The AT2 receptor isolated from N1E-115 cells exhibited a similar pharmacology as the Peak III AT2 receptor, in that CGP42112A was more effective at displacing 125I-Ang II binding activity than was PD123319. The AT2 receptor clone was also shown to be insensitive to the actions of GTP gamma S, as well as demonstrated increased binding activity in the presence of DTT, identical to the Peak III AT2 receptor. Lastly, immunoblot analysis of membranes prepared from COS-1 cells transfected with the AT2 receptor cDNA from N1E-115 cells did not demonstrate any immune-specific bands with the AT2-directed antisera. Characterization of an AT2 receptor cDNA isolated from N1E-115 cells reveals that this clone is identical to the Peak III type of AT2 receptor.

Intracerebroventricular administration of angiotensin type 1 (AT1) receptor antisense oligonucleotides attenuate thirst in the rat

The central actions of the peptide hormone angiotensin II (AngII) are importantly involved in body fluid homeostasis. Included amongst these actions is a potent dipsogenic response that has been implicated in the thirst that develops during many forms of extracellular dehydration. The use of highly selective receptor antagonists has revealed that the Type 1 (AT1), and not the Type 2 (AT2), AngII receptor subtype mediates this drinking response. More recently, antisense oligonucleotides specific for the AT1 receptor have been developed and after intracerebroventricular (i.c.v.) administration, they significantly reduce the dipsogenic response elicited by a similar injection of AngII. In the present study AT1 antisense oligonucleotides were used to further investigate their effect on experimentally induced thirst in the rat. In addition, immunohistochemical analysis of biotin-labeled oligonucleotides was performed in order to correlate the behavioral effects of the oligonucleotides with their distribution in the brain. The results demonstrated that the antidipsogenic effects of the oligonucleotides were dose and time-dependent and were limited to those thirst challenges that involve activation of the renin-angiotensin system. Collectively, these results demonstrate the efficacy and behavioral specificity of these oligonucleotides, as well as their utility in investigating the physiological role of cerebral AngII receptor subpopulations in various models of thirst.

Intracerebroventricular administration of AT1 receptor antisense oligonucleotides inhibits the behavioral actions of angiotensin II

Antisense oligonucleotides were developed to study the expression and function of angiotensin type 1 (AT1) receptors in cultured cells and brain. In both liver epithelial WB and neuroblastoma N1E-115 cells AT1 antisense oligomers substantially decreased AT1 receptor density, whereas angiotensin type 2 (AT2) receptors remained unchanged. Similarly, repeated intracerebroventricular injections of AT1 antisense oligomers in rats decreased AT1 receptor density in hypothalamic-thalamic-septal tissue, and AT2 receptors were unaffected. Intracerebroventricular antisense oligomers also attenuated drinking elicited by intracerebroventricular angiotensin II but not the cholinomimetic carbachol. Collectively, these results demonstrate that antisense oligonucleotides attenuate angiotensin receptor expression and function in behaving animals.