Genomics-driven derivatization of the bioactive fungal sesterterpenoid variecolin: Creation of an unnatural analogue with improved anticancer properties.

A biosynthetic gene cluster for the bioactive fungal sesterterpenoids variecolin (1) and variecolactone (2) was identified in Aspergillus aculeatus ATCC 16872. Heterologous production of 1 and 2 was achieved in Aspergillus oryzae by expressing the sesterterpene synthase VrcA and the cytochrome P450 VrcB. Intriguingly, the replacement of VrcB with homologous P450s from other fungal terpenoid pathways yielded three new variecolin analogues (5-7). Analysis of the compounds' anticancer activity in vitro and in vivo revealed that although 5 and 1 had comparable activities, 5 was associated with significantly reduced toxic side effects in cancer-bearing mice, indicating its potentially broader therapeutic window. Our study describes the first tests of variecolin and its analogues in animals and demonstrates the utility of synthetic biology for creating molecules with improved biological activities.

Contrast-Enhanced Computed Tomography and Laboratory Parameters as Non-Invasive Diagnostic Markers of Pancreatic Fibrosis.

Pancreatic fibrosis (PF) is a part of the pathogenesis in most pancreatic disorders and plays a crucial role in chronic pancreatitis development. The aim of our study was to investigate a relationship between PF grade and signs in resected pancreatic specimens, and the results of both multidetector computed tomography (MDCT) post-processing parameters and fibronectin (FN), hyaluronic acid (HA), matrix metalloproteinase (MMP)-1, and MMP-9 serum levels. The examination results of 74 patients were analyzed. The unenhanced pancreas density (UPD) value and contrast enhancement ratio (CER) showed statistically significant differences in groups with peri- and intralobular fibrosis grades, an integrative index of fibrosis, inflammation in pancreatic tissue, and pancreatic duct epithelium metaplasia, while the normalized contrast enhancement ratio in the venous phase (NCER VP) significantly differed with the perilobular fibrosis grade, integrative fibrosis index, and inflammation (p < 0.05). The blood FN level showed a weak positive correlation with the intralobular fibrosis grade (rho = 0.32, p = 0.008). The blood level of HA positively correlated with the presence of prominent and enlarged peripheral nerves (rho = 0.28, p = 0.02) and negatively correlated with the unenhanced pancreas density value (rho = -0.42, p = 0.0001). MMP-1 and MMP-9 values' intergroup analysis and correlation did not show any statistical significance. The UPD value, NCER VP, and CER, as well as blood levels of FN and HA, could be used in non-invasive PF diagnosis.

X-ray micro-computed tomography in the assessment of penile cavernous fibrosis in a rabbit castration model.

BACKGROUND: Current assessment methods of penile cavernous fibrosis in animal models have limitations due to the inability to provide complex and volume analysis of fibrotic alterations. OBJECTIVE: The aim was to evaluate micro-computed tomography for assessment of cavernous fibrosis and compare it with histological, histochemical, immunohistochemical, and RT-PCR analysis. MATERIALS AND METHODS: A controlled trial was performed involving 25 New Zealand male rabbits with induced testosterone deficiency by orchidectomy. Penile samples were obtained before and after 7, 14, 21, and 84 days from orchidectomy. We consistently performed (a) gray value analysis of corpora cavernosa 3D models reconstructed after micro-computed tomography, (b) morphometry of smooth muscles/connective tissue ratio, collagen type I/III ratio, and area of TGF-beta-1 expression in corpora cavernosa, and (c) RT-PCR of TGF-beta-1 expression. RESULTS: Micro-computed tomography allowed visualization of penile structures at a resolution comparable to light microscopy. Gray values of corpora cavernosa decreased from 1673 (1512-1773) on the initial day to 1184 (1089-1232) on the 21st day (p < 0.005). However, on the 84th day, it increased to 1610 (1551-1768). On 21st and 84th days, there was observed a significant decrease in smooth muscle/connective tissue ratio and a significant increase in collagen type I/III ratio (p < 0.05). TGF-beta1 expression increased on the 84th day according to immunohistochemistry (p < 0.005). RT-PCR was impossible to conduct due to the absence of RNA in obtained samples after micro-CT. DISCUSSION AND CONCLUSIONS: Micro-computed tomography provided 3D visualization of entire corpora cavernosa and assessment of radiodensity alterations by gray value analysis in fibrosis progression. We speculate that gray value changes at early and late fibrosis stages could be related to tissue reorganization. RT-PCR is impossible to conduct on tissue samples studied by micro-CT due to RNA destruction. We also suggest that micro-computed tomography could negatively affect the immunohistochemical outcome, as a significant increase of TGF-beta-1 expression occurs later than histological fibrotic signs.

Visualization of different anatomical parts of the enucleated human eye using X-ray micro-CT imaging.

Micro-CT visualization allows reconstruction of eye structures with the resolution of light microscopy and estimation of tissue densities. Moreover, this method excludes damaging procedures and allows further histological staining due to the similar steps in the beginning. We have shown the feasibility of the lab-based micro-CT machine usage for visualization of clinically important compartments of human eye such as trabecular outflow pathway, retina, iris and ciliary body after pre-treatment with iodine in ethanol. We also identified the challenges of applying this contrasting technique to lens, cornea, and retina and proposed alternative staining methods for these tissues. Thereby this work provides a starting point for other studies for imaging of human eyes in normal and pathological conditions using lab-based micro-CT systems.