Evaluation of the ESUR PI-RADS scoring system for multiparametric MRI of the prostate with targeted MR/TRUS fusion-guided biopsy at 3.0 Tesla.

OBJECTIVES: To evaluate the Prostate Imaging Reporting and Data System (PI-RADS) proposed by the European Society of Urogenital Radiology (ESUR) for detection of prostate cancer (PCa) by multiparametric magnetic resonance imaging (mpMRI) in a consecutive cohort of patients with magnetic resonance/transrectal ultrasound (MR/TRUS) fusion-guided biopsy. METHODS: Suspicious lesions on mpMRI at 3.0 T were scored according to the PI-RADS system before MR/TRUS fusion-guided biopsy and correlated to histopathology results. Statistical correlation was obtained by a Mann-Whitney U test. Receiver operating characteristics (ROC) and optimal thresholds were calculated. RESULTS: In 64 patients, 128/445 positive biopsy cores were obtained out of 95 suspicious regions of interest (ROIs). PCa was present in 27/64 (42%) of the patients. ROC results for the aggregated PI-RADS scores exhibited higher areas under the curve compared to those of the Likert score. Sensitivity/Specificity for the following thresholds were calculated: 85 %/73 % and 67 %/92 % for PI-RADS scores of 9 and 10, respectively; 85 %/60 % and 56 %/97 % for Likert scores of 3 and 4, respectively [corrected. CONCLUSIONS: The standardised ESUR PI-RADS system is beneficial to indicate the likelihood of PCa of suspicious lesions on mpMRI. It is also valuable to identify locations to be targeted with biopsy. The aggregated PI-RADS score achieved better results compared to the single five-point Likert score. KEY POINTS: • The ESUR PI-RADS scoring system was evaluated using multiparametric 3.0-T MRI. • To investigate suspicious findings, transperineal MR/TRUS fusion-guided biopsy was used. • PI-RADS can guide biopsy locations and improve detection of clinically significant cancer. • Biopsy procedures can be optimised, reducing unnecessary negative biopsies for patients. • The PI-RADS scoring system may contribute to more effective prostate MRI.

Toll-like receptor 2-deficient mice are protected from insulin resistance and beta cell dysfunction induced by a high-fat diet.

AIMS/HYPOTHESIS: Inflammation contributes to both insulin resistance and pancreatic beta cell failure in human type 2 diabetes. Toll-like receptors (TLRs) are highly conserved pattern recognition receptors that coordinate the innate inflammatory response to numerous substances, including NEFAs. Here we investigated a potential contribution of TLR2 to the metabolic dysregulation induced by high-fat diet (HFD) feeding in mice. METHODS: Male and female littermate Tlr2(+/+) and Tlr2(-/-) mice were analysed with respect to glucose tolerance, insulin sensitivity, insulin secretion and energy metabolism on chow and HFD. Adipose, liver, muscle and islet pathology and inflammation were examined using molecular approaches. Macrophages and dendritic immune cells, in addition to pancreatic islets were investigated in vitro with respect to NEFA-induced cytokine production. RESULTS: While not showing any differences in glucose homeostasis on chow diet, both male and female Tlr2(-/-) mice were protected from the adverse effects of HFD compared with Tlr2(+/+) littermate controls. Female Tlr2(-/-) mice showed pronounced improvements in glucose tolerance, insulin sensitivity, and insulin secretion following 20 weeks of HFD feeding. These effects were associated with an increased capacity of Tlr2(-/-) mice to preferentially burn fat, combined with reduced tissue inflammation. Bone-marrow-derived dendritic cells and pancreatic islets from Tlr2(-/-) mice did not increase IL-1beta expression in response to a NEFA mixture, whereas Tlr2(+/+) control tissues did. CONCLUSION/INTERPRETATION: These data suggest that TLR2 is a molecular link between increased dietary lipid intake and the regulation of glucose homeostasis, via regulation of energy substrate utilisation and tissue inflammation.

Structural analysis of prokaryotic and eukaryotic 5S rRNAs by RNase H.

The availabilities of single-stranded 5S rRNA regions c, d and d' for base pairing interactions were analyzed by using synthetic DNA oligomers. Hybrid formation was detected by the endonucleolytical mode of the RNA-DNA specific action of RNase H. Provided that the hybrid interaction involved 6 successive base pairs, 5S rRNA loop c nucleotides 42-47 displayed accessibility in Escherichia coli, Bacillus stearothermophilus and Thermus thermophilus 5S rRNAs as well as in eukaryotic 5S rRNAs from Saccharomyces carlsbergensis, Rattus rattus and Equisetum arvense. Investigating eubacterial 5S rRNA regions d and d' (nucleotides 71-76 and 99-105, respectively), susceptibility was observed in E. coli 5S rRNA which, however, decreases in B. stearothermophilus and even more so in T. thermophilus 5S rRNA. For additional evaluation of the data obtained by RNase H cleavage, association constants of the hexanucleotides were determined by equilibrium dialysis at 4 degrees C for B. stearothermophilus 5S rRNA. The results obtained reveal that nucleotides 36-41 of B. stearothermophilus 5S rRNA are inaccessible for Watson-Crick interaction, which suggests that this part of loop c is in a structurally constrained configuration, or buried in the tertiary structure or involved in tertiary interactions.

Two amino acid substitutions in the tomato mosaic virus 30-kilodalton movement protein confer the ability to overcome the Tm-2(2) resistance gene in the tomato.

The Tm-2(2) resistance gene is used in most commercial tomato cultivars for protection against infection with tobacco mosaic virus and its close relative tomato mosaic virus (ToMV). To study the mechanism of this resistance gene, cDNA clones encompassing the complete genome of a ToMV strain (ToMV-2(2)) that was able to break the Tm-2(2) resistance were generated. Chimeric full-length viral cDNA clones were constructed under the control of the cauliflower mosaic virus 35S RNA promoter, combining parts of the wild-type virus and ToMV-2(2). Using these clones in cDNA infection experiments, we showed that the 30-kDa movement protein of ToMV-2(2) is responsible for overcoming the Tm-2(2) resistance gene in the tomato. DNA sequence analysis revealed four amino acid exchanges between the 30-kDa proteins from wild-type ToMV and ToMV-2(2), Lys-130 to Glu, Gly-184 to Glu, Ser-238 to Arg, and Lys-244 to Glu. To clarify the involvement of the altered amino acid residues in the resistance-breaking properties of the ToMV-2(2) movement protein, different combinations of these amino acid exchanges were introduced in the genome of wild-type ToMV. Only one mutant strain which contained two amino acid substitutions, Arg-238 and Glu-244, was able to multiply in Tm-2(2) tomato plants. Both amino acid exchanges are found within the carboxy-terminal region of the movement protein, which displays a high variability among different tobamoviruses and has been shown to be dispensable for virus transport in tobacco plants. These observations suggest that the resistance conferred by the Tm-2(2) gene against ToMV depends on specific recognition events in this host-pathogen interaction rather than interfering with fundamental functions of the 30-kDa protein.

Metal Interactions with Microbial Biofilms in Acidic and Neutral pH Environments.

Microbial biofilms were grown on strips of epoxy-impregnated filter paper submerged at four sites in water contaminated with metals from mine wastes. At two sample stations, the water was acidic (pH 3.1); the other sites were in a lake restored to a near neutral pH level by application of a crushed limestone slurry. During a 17-week study period, planktonic bacterial counts increased from 10 to 10 CFU/ml at all sites. Biofilm counts increased rapidly over the first 5 weeks and then leveled to 10 CFU/cm in the neutral pH system and 10 CFU/cm at the acidic sites. In each case, the biofilms bound Mn, Fe, Ni, and Cu in excess of the amounts adsorbed by control strips covered with nylon filters (pore size, 0.22 mum) to exclude microbial growth; Co bound under neutral conditions but not under acidic conditions. Conditional adsorption capacity constants, obtained graphically from the data, showed that biofilm metal uptake at a neutral pH level was enhanced by up to 12 orders of magnitude over acidic conditions. Similarly, adsorption strength values were usually higher at elevated pH levels. In thin sections of the biofilms, encapsulated bacterial cells were commonly found enmeshed together in microcolonies. The extracellular polymers often contained iron oxide precipitates which generated weak electron diffraction patterns with characteristic reflections for ferrihydrite (Fe(2)O(3) . H(2)O) at d equaling 0.15 and 0.25 nm. At neutral pH levels, these deposits incorporated trace amounts of Si and exhibited a granular morphology, whereas acicular crystalloids containing S developed under acidic conditions.

Activation of a truncated PR-1 promoter by endogenous enhancers in transgenic plants.

PR-1 genes are induced by various environmental stimuli such as pathogen attack or exposure of the plants to certain chemicals. To examine the regulation of these genes, the 5' flanking regions of the PR-la gene and of two PR-1 pseudogenes were joined by a transcriptional fusion to the Escherichia coli beta-glucuronidase (GUS) gene. These constructs were stably integrated into the tobacco genome and independent primary transformants were monitored for the expression of the reporter gene. Unexpectedly, out of 55 transformants analysed, four plants exhibited considerable GUS activities without any inductive treatment of the plants. Expression of the endogenous PR-1 genes, however, could not be detected in these plants. Primer extension analyses revealed correct initiation of the PR1/GUS hybrid transcripts from the PR-1a TATA box. When the plants were analysed at the cellular level, clear differences regarding the tissue specificity of expression of the reporter gene were observed. These results strongly suggest that the PR1/GUS hybrid promoter expression cassettes may be activated when integrated in the vicinity of heterologous enhancer elements dispersed in the tobacco genome. In order to support this hypothesis, domain B of the enhancer of the 35S RNA promoter from cauliflower mosaic virus (CaMV) was fused to various PR1/GUS hybrid genes upstream as well as downstream from the RNA start site. These constructs were stably introduced into the tobacco genome. In any primary transformant analysed, strong GUS activities were observed with the PR1/GUS hybrid RNAs originating from the normal transcription start site of the PR-1a gene. The tissue specificity of gene expression was identical to that described previously for the CaMV 35S domain B enhancer element. Thus, modulations of the transcriptional activity of the PR-1 promoter can be achieved by heterologous enhancers in transgenic plants and may be encountered upon random integration of PR-1 promoter constructs into the tobacco genome.

[Effect of bFGF on regeneration of distracted mandibles after radiation]. / Einfluss von bFGF auf die Regeneration von distrahierten Unterkiefern nach Radiatio.

The potential of distraction osteogenesis in mandibular reconstruction has been limited by its questionable efficacy in previously irradiated bone. The possible osteogenetic effect of recombinant human basic fibroblast growth factor (bFGF) on lengthening of irradiated mandibles was investigated in beagle dogs. We studied nine adult dogs which underwent a full course of external beam radiation therapy (60 Gy/30 fractions). Six months after completion of radiotherapy, the molars were extracted bilaterally followed by bone lengthening of the mandible using an intraoral device. On postoperative day 3 and 7 we injected 10 micrograms bFGF into the osteotomy site of each right hemimandible. The left sides were used as controls. The time course in ossification of the distracted area was evaluated at 2, 4, and 6 weeks after completion of bone lengthening. The radiographs of the newly formed bone tissue were measured by digital image analysis. Corresponding to the radiographic findings, the histological examination of the removed jaws showed an earlier and more intensive bone formation in the treated side after 2, 4, and 6 weeks compared to the control side. We conclude that bFGF promotes the ossification of distracted mandibles after radiation therapy in dogs.