The temporal and spatial dynamics of microscale collagen scaffold remodeling by smooth muscle cells

Smooth muscle cells (SMCs) and collagen scaffolds are widely used in vascular tissue engineering but their interactions in remodeling at the microscale level remained unclear. We characterized microscale morphologic alterations of collagen remodeled by SMCs in six dimensions: three spatial, time, multichannel and multi-position dimensions. In live imaging assays, computer-assisted cell tracking showed locomotion characteristics of SMCs; reflection and fluorescent confocal microscopy and spatial reconstruction images of each time point showed detailed morphologic changes of collagen fibers and spatial collagen–SMC interactions. The density of the collagen around the SMCs was changed dynamically by the leading edges of the cells. The density of the collagen following 24 h of cell-induced remodeling increased 51.61 ± 9.73% compared to unremodeled collagen containing cells for 1 h (P < 0.0001, n = 40) (NS vs. collagen without cells). Fast Fourier transform analysis showed that the collagen fibers' orientation changed from random (alignment index = 0.047 ± 0.029, n = 40) after 1 h into concordant with that of the SMCs (alignment index = 0.379 ± 0.098, P < 0.0001, n = 40) after 24 h. Mosaic imaging extended the visual field from a single cell to a group of cells in one image without loss of optical resolution. Direct visualization of alignment of actin fibers and collagen fibers showed the molecular machinery of the process of scaffold remodeling. This is a new approach to better understanding the mechanism of scaffold remodeling and our techniques represent effective tools to investigate the interactions between cells and scaffold in detail at the microscale level.     

The role of the PI3K-Akt signal transduction pathway in Autographa californica multiple nucleopolyhedrovirus infection of Spodoptera frugiperda cells

Many viruses activate the phosphatidylinositol 3-kinase (PI3K)-Akt signaling pathway, thereby modulating diverse downstream signaling pathways associated with antiapoptosis, proliferation, cell cycling, protein synthesis and glucose metabolism, in order to augment their replication. To date, the role of the PI3K-Akt pathway in Baculovirus replication has not been defined. In the present study, we demonstrate that infection of Sf9 cells with Autographa californica multiple nucleopolyhedrovirus (AcMNPV) elevated cellular Akt phosphorylation at 1 h post-infection. The maximum Akt phosphorylation occurred at 6 h post-infection and remained unchanged until 18 h post-infection. The PI3K-speci?c inhibitor, LY294002, suppressed Akt phosphorylation in a dose-dependent manner, suggesting that AcMNPV-induced Akt phosphorylation is PI3K-dependent. The inhibition of PI3K-Akt activation by LY294002 significantly reduced the viral yield, including a reduction in budded viruses and occlusion bodies. The virus production was reduced only when the inhibitor was added within 24 h of infection, implying that activation of PI3K occurred early in infection. Correspondingly, both viral DNA replication and late (VP39) and very late (POLH) viral protein expression were impaired by LY294002 treatment; LY294002 had no effect on immediate-early (IE1) and early-late (GP64) protein expression. These results demonstrate that the PI3K-Akt pathway is required for efficient Baculovirus replication.     

Genetic characterization of H1N1 swine influenza A viruses isolated in eastern China

Three influenza H1N1 viruses were isolated in 2005 from pigs with respiratory disease on a farm in eastern China. The three isolates were characterized to determine their probable origin. Each of the eight genes of the isolates was most closely related to the corresponding gene from the classical swine H1N1 virus. Also, phylogenetic analysis further confirmed that each of the eight genes of the isolates was closely related to the classical swine H1N1 viruses, especially those isolated in China. The HA1 proteins of the three isolates were identical to that of A/Swine/Guangdong/1/01, a virus isolated in 2001 in China, even though three nucleotide differences were observed. These results further support the concept that swine can serve as a reservoir of genetically stable influenza viruses.     

伽玛刀治疗视神经鞘脑膜瘤长期疗效评价

0例,无变化8例,增大2例,肿瘤控制率为93.3%(28/30).治疗45个月后肿瘤控制率趋于稳定.治疗后视力提升11例(36.7%).减退6例(20.0%),无变化13例(43.3%).4例曾出现一过性球结膜水肿.患者眼眶肿瘤手术史、肿瘤容积和累及范围等因素与肿瘤控制率均无统计学意义上的关联(P>0.05).结论 伽玛刀治疗视神经鞘脑膜瘤可在较长时期内控制肿瘤生长,可保留部分视力,并发症较少.     

Computer-assisted image analysis of amyloid deposits in abdominal fat pad aspiration biopsies

Amyloidosis is a heterogeneous group of diseases with a common outcome: deposition of insoluble protein in the visceral organs and tissues. Primary amyloidosis is a consequence of different plasma cell disorders, and it is the most common form of amyloidosis in the United States with an estimated 2,000 new cases annually. Other forms of amyloidosis include chronic inflammatory processes, familial type of amyloidosis, and localized forms like Alzheimer's disease.The diagnosis of amyloidosis is based on the clinical picture and demonstration of amyloid deposit in tissues with Congo-red stain. In our article, we describe a simple methodology for image analysis of fat pad biopsies for amyloidosis using a commercially available software Adobe Photoshop CS3(c) Extended Edition. The principle is based on calculation of the mean gray value of each blue and green channel and comparison of their ratios. As a negative control, we have used samples from heart, scar tissue, and skin with their representative control. Fibrous tissue often gives a white:blue to blue:green birefringence, which often is confused with the apple: green birefringence of the amyloid stain; however, we were successful in discriminating these colors using the methodology described in this article. We also analyzed 22 patients with at least 2 years follow-up in our institution. The specificity and the sensitivity of the computer-assisted image analysis were calculated to be 75% and 100%, respectively. These results are in agreement with the published papers (references here); however, caution should be exercised before drawing firm conclusions because of the small sample size presented here.     

Axon terminals expressing vesicular glutamate transporter VGLUT1 or VGLUT2 within the trigeminal motor nucleus of the rat: Origins and distribution patterns

Little is known about the significance of the two types of glutamatergic neurons (those expressing vesicular glutamate transporter VGLUT1 or VGLUT2) in the control of jaw movements. We thus examined the origin and distribution of axon terminals with VGLUT1 or VGLUT2 immunoreactivity within the trigeminal motor nucleus (Vm) in the rat. The Vm was divided into the dorsolateral division (Vm.dl; jaw‐closing motoneuron pool) and the ventromedial division (Vm.vm; jaw‐opening motoneuron pool). VGLUT1‐immunopositive terminals were seen within the Vm.dl only, whereas VGLUT2‐immunopositive ones were distributed to both the Vm.dl and the Vm.vm. Transection of the motor root eliminated almost all VGLUT1‐immunopositive axons in the Vm.dl, with no changes of VGLUT2 immunoreactivity in the two divisions, indicating that the VGLUT1‐ and VGLUT2‐immunopositive axons came from primary afferents in the mesencephalic trigeminal nucleus and premotor neurons for the Vm, respectively. In situ hybridization histochemistry revealed that VGLUT2 neurons were much more numerous than VGLUT1 neurons in the regions corresponding to the reported premotoneuron pool for the Vm. The results of immunofluorescence labeling combined with anterograde tract tracing further indicated that premotor neurons with VGLUT2 in the trigeminal sensory nuclei, the supratrigeminal region, and the reticular region ventral to the Vm sent axon terminals contacting trigeminal motoneurons and that some of the VGLUT1‐expressing premotor neurons in the reticular region ventral to the Vm sent axon terminals to jaw‐closing motoneurons. The present results suggested that the roles played by glutamatergic neurons in controlling jaw movements might be different between VGLUT1‐ and VGLUT2‐expressing neurons. J. Comp. Neurol. 512:595–612, 2009. © 2008 Wiley‐Liss, Inc.     

Improvement of prostate cancer detection by integrating the PSA test with miRNA expression profiling

Prostate-specific antigen (PSA) test is limited in prostate cancer diagnosis due to its inaccuracy. A new approach which integrates the PSA test with miRNA profiling was investigated to improve prostate cancer diagnosis. Six prostate cancer-related miRNAs (miR-16, -21, -34c, -101, -125b, -141) were tested in five cultured prostate cell lines and 20 human prostate specimens. We found that the miRNA expression profiles were significantly different between nontumorigenic and tumorigenic cell lines and specimens. Positive predictive value analysis of prostate cancer was increased from 40% to 87.5% by integrating patient PSA blood levels with miR-21 and miR-141 profiles.