Evaluation of five DNA extraction methods for detection of H. pylori in formalin-fixed paraffin-embedded (FFPE) liver tissue from patients with hepatocellular carcinoma

Since Helicobacter spp. DNA was identified in liver tissue resected from patients with hepatocelullar carcinoma (HCC), researchers have suggested a role of this bacterium in hepatic carcinogenesis. Archives of formalin-fixed, paraffin-embedded (FFPE) tissues represent an extraordinary source for clinical studies providing many advantages. However, DNA extraction from FFPE tissues is laborious, time-consuming and still remains a challenge. The aim of this study was to evaluate five protocols for DNA extraction from FFPE liver obtained from patients with HCC in order to detect Helicobacter pylori DNA. These methods were: (1) QIAamp FFPE Tissue Kit, (2) QIAamp DNA Mini Kit, (3) Wizard SV Genomic DNA Purification System, (4) RealiaPrep FFPE gDNA Miniprep System and (5) phenol–chloroform. H. pylori detection was performed using 16S rRNA gene amplification by PCR. The highest total amount of DNA was obtained using the phenol–chloroform method. Analyses of 16S rRNA gene amplification did not show statistically significant differences among the methods (p = 0.466), although the highest percentage of positive cases (70%) was found in samples extracted with phenol-chloroform. We suggest that of the five methods evaluated, phenol/chloroform is the most suitable for detection of H. pylori in FFPE liver from patients with HCC.     

In vivo toxicity evaluation of two polyoxotungstates with potential antidiabetic activity using Wistar rats as a model system

In this study, the in vivo hypoglycemic effect of a donut-shaped polyanion salt (NH₄)₁₄[Na@P₅W₃₀O₁₁₀]·31H₂O {NaP₅W₃₀} and its Ag-containing derivative K₁₄[Ag@P₅W₃₀O₁₁₀]·22H₂O·6KCl {AgP₅W₃₀}, as well as their hepatotoxicity and nephrotoxicity, was evaluated. In the screening hypoglycemic study, Wistar albino rats with streptozotocin induced diabetes were treated intraperitoneally with three single doses (5, 10, and 20 mg per kg per b.w.) of both investigated polyoxotungstates. The blood glucose levels, measured before and after 2, 4 and 6 h polyoxotungstate application, showed that both studied compounds induced the most pronounced and time dependent glucose lowering effects at the doses of 20 mg kg⁻¹. Thus, daily doses of 20 mg kg⁻¹ were administered to Wistar albino rats orally for 14 days in further toxicity examinations. The serum glucose concentration and biochemical parameters of kidney and liver function, as well as a histopathological analysis of kidney and liver tissues were evaluated 14 days after the polyoxotungstate administration. Both investigated compounds did not induce statistically significant alterations of the serum glucose and uric acid concentrations, as well as some of the liver function markers (serum alanine and aspartate aminotransferases, and alkaline phosphatase activities). However, the significant decrease in serum total protein and albumin concentrations and the increase in biochemical parameters of renal function – serum urea (up to 63.1%) and creatinine concentrations (up to 23.3%) were observed for both polyoxotungstates. In addition, the detected biochemical changes were in accordance with kidney and liver histhopathological analysis. Accordingly, the hepatotoxic and nephrotoxic effects of these potential antidiabetic polyoxotungstates could be considered as mild.

Study of the in vivo hypoglycemic effect, hepatotoxicity and nephrotoxicity of a donut-shaped polyanion salt (NH₄)₁₄[Na@P₅W₃₀O₁₁₀]·31H₂O {NaP₅W₃₀} and its Ag-containing derivative K₁₄[Ag@P₅W₃₀O₁₁₀]·22H₂O·6KCl {AgP₅W₃₀}.     

Anti-L-selectin monoclonal antibody treatment in mice enhances tumor growth by preventing CTL sensitization in peripheral lymph nodes draining the tumor area

To examine the in vivo contribution of L-selectin in the sensitization of tumor-specific CTL, we investigated the effects of treatment with the anti-L-selectin monoclonal antibody (MAb) MEL-14 on the immune response to Moloney-murine sarcoma virus (M-MSV)-induced tumors, which exhibit spontaneous regression following generation of a strong virus-specific CTL response. Daily systemic administration of MEL-14 for 10 days to M-MSV-injected mice gave rise to larger sarcomas that persisted for a longer time, compared with those arising in control mice injected with virus only. The enhanced tumor growth could not be attributed to cytotoxic activity on leukocytes by MEL-14 since no reduction in the total cell number was detected in peripheral blood and spleen of MAb-treated mice. Evaluation of the immunological response in MAb-treated animals revealed a strong reduction in the generation of virus-specific CTL precursors (CTLp) in tumor-draining peripheral lymph nodes (PLN) 10 and 15 days after M-MSV injection, while in spleen, where lymphocyte localization is independent of L-selectin expression, CTLp generation was only delayed. By day 20, when tumors had begun to regress, the CTLp number showed a marked increase in both spleen and local PLN, where naive recirculating CTL could now enter because L-selectin was no longer down-regulated or blocked by the injected MAb. Our findings indicate that functional inactivation of L-selectin by MEL-14 treatment prevented migration of naive L-selectin ⁺ CTL through high endothelial venules (HEV) and their accumulation in PLN draining the tumor area, thereby precluding the initiation of a tumor-specific CTL response that takes place primarily at this site. © 1996 Wiley-Liss, Inc.     

Motor control after spinal cord injury: Assessment using surface EMG

The brain motor control assessment (BMCA) protocol is a comprehensive multichannel surface EMG recording used to characterize motor control features in persons with upper motor neuron dysfunction. Key information is contained in the overall temporal pattern of motor unit activity, observed in the EMG (RMS) envelope. In paralysis, a rudimentary form of suprasegmental control of tonic and phasic reflexes can be demonstrated. EMG patterns evoked by voluntary and passive maneuvers and by volitional modulation of reflex responses reveal features of motor control not apparent in the clinical examination. Such subclinical findings may explain paradoxically different responses in apparently similar SCI subjects, and may be used to monitor spontaneous or induced changes. The recording protocol, examples of EMG patterns, and their prevalence in 40 spinal cord injured (SCI) subjects are presented, and compared with 5 healthy subjects. © 1996 John Wiley & Sons, Inc.     

Substantial Improvement of High Temperature Strength of New-Generation Nano-Oxide-Strengthened Alloys by Addition of Metallic Yttrium

Oxide-dispersion-strengthened (ODS) Fe-Al-Y₂O₃-based alloys (denoted as FeAlOY) containing 5 vol. % of nano-oxides have a potential to become top oxidation and creep-resistant alloys for applications at temperatures of 1100–1300 °C. Oxide dispersoids cause nearly perfect strengthening of grains; thus, grain boundaries with limited cohesive strength become the weak link in FeAlOY in this temperature range. One of the possibilities for significantly improving the strength of FeAlOY is alloying with appropriate elements and increasing the cohesive strength of grain boundaries. Nearly 20 metallic elements have been tested with the aim to increase cohesive strength in the frame of preliminary tests. A positive influence is revealed for Al, Cr, and Y, whereby the influence of Y is enormous (addition of 1% of metallic Y increases strength by a factor of 2), as it is presented in this paper.     

A quantitative determination of lipid bilayer deposition efficiency using AFM

The efficacy of a number of different methods for depositing a dimyristoylphosphatidylcholine (DMPC) lipid bilayer or DMPC–cholesterol (3 : 1) mixed bilayer onto a silicon substrate has been investigated in a quantitative manner using atomic force microscopy (AFM) image analysis to extract surface coverage. Complementary AFM-IR measurements were used to confirm the presence of the lipids. For the Langmuir–Blodgett/Schaefer deposition method at temperatures below the chain-melting transition temperature (T_m), a large number of bilayer defects resulted when DMPC was deposited from a water subphase. Addition of calcium ions to the trough led to smaller, more frequent defects, whereas addition of cholesterol to the lipid mixture led to a vast improvement in bilayer coverage. Poor coverage was achieved for deposition at temperatures above T_m. Formation of the deposited bilayer from vesicle fusion proved a more reliable method for all systems, with formation of near-complete bilayers within 60 seconds at temperatures above T_m, although this method led to a higher probability of multilayer formation and rougher bilayer surfaces.

The efficacy of different methods for depositing a DMPC or mixed DMPC–cholesterol (3 : 1) lipid bilayer onto a silicon substrate has been investigated in a quantitative manner using atomic force microscopy image analysis to extract surface coverage.     

Cortical evoked potentials and somatosensory perception in chronic spinal cord injury patients

The correlation between somatosensory evoked potentials (SEPs) and sensory perception was studied in 110 patients with traumatic chronic spinal cord lesions. Perception thresholds over the legs for light touch, vibratory sensibility, temperature and thermal pain were tested together with recordings of tibial and peroneal SEPs. Tibial nerve SEPs correlated better with sensory perception than peroneal nerve SEPs. Normal tibial nerve SEPs were not present with absent or trace vibratory sensibility and vice versa. However, we found many exceptions to the correlation between temperature and pain perception and SEPs. Light touch, vibratory sensibility, and SEPs were highly correlated between each other, while temperature and pain perception correlated poorly to these other modalities. This represents an evident segregation of touch perception, vibratory sensibility and SEPs, which are thought to share dorsal columns as a common ascending pathway, and temperature and pain perception known to be related to the spinothalamic system.     

Synthesis of C-prenylated analogues of stilbenoid methyl ethers and their cyclic dihydrobenzopyranyl derivatives as potential anti-inflammatory agents

An efficient and versatile synthesis of the naturally occurring C-prenylated stilbenoid methyl ethers and their synthetic analogues is presented. The synthesis represents a six step convergent process including an optimised C-prenylation method. Furthermore, during the demethylation process, six new dihydro-benzopyranyl derivatives were obtained and isolated.

An efficient and versatile synthesis of the naturally occurring C-prenylated stilbenoid methyl ethers and synthetic analogs has been developed.     

Evaluation of a decision support system for interpretation of myocardial perfusion gated SPECT

PURPOSE: We have recently presented a decision support system for interpreting myocardial perfusion scintigraphy (MPS). In this study, we wanted to evaluate the system in a separate hospital from where it was trained and to compare it with a quantification software package. METHODS: A completely automated method based on neural networks was trained for the interpretation of MPS regarding myocardial ischaemia and infarction using 418 MPS from one hospital. Features from each examination describing rest and stress perfusion, regional and global function were used as inputs to different neural networks. After the training session, the system was evaluated using 532 MPS from another hospital. The test images were also processed with the quantification software package Emory Cardiac Toolbox (ECTb). The images were interpreted by experienced clinicians at both the training and the test hospital, regarding the presence or absence of myocardial ischaemia and/or infarction and these interpretations were used as gold standard. RESULTS: The neural network showed a sensitivity of 90% and a specificity of 85% for myocardial ischaemia. The specificity for the ECTb was 46% (p < 0.001), measured at the same sensitivity. The neural network sensitivity for myocardial infarction was 89% and the specificity 96%. The corresponding specificity for the ECTb was 54% (p < 0.001). CONCLUSION: A decision support system based on neural networks presents interpretations more similar to experienced clinicians compared to a conventional automated quantification software package. This study shows the feasibility of disseminating the expertise of experienced clinicians to less experienced physicians by the use of neural networks.