Multicenter evaluation of the phosphorylcholine-coated biodivYsio stent in short de novo coronary lesions: The SOPHOS study

AIMS: The BiodivYsio trade mark stent (Biocompatibles Ltd, Farnham, UK) is coated with a phosphorylcholine (PC)-containing copolymer to confer biocompatibility. The SOPHOS (Study Of PHosphorylcholine coating On Stents) study was designed to assess the safety and efficacy of this novel coronary stent and by indirect comparison to indicate equivalence with other formal stent studies. METHODS AND RESULTS: Patients with angina and a single short (#x2A7F;12 mm) de novo lesion in a native coronary artery of >/=2.75 mm diameter were included. A total of 425 patients were allocated in 24 centers. Clinical data were collected at one-, six- and nine-month follow-up. Angiography was performed before and after the stent implantation. In addition, in the first 200 patients (SOPHOS A) angiography was routinely performed at six months. The following 225 patients (SOPHOS B) were merely followed up clinically. The primary end-point of the study, the six-month MACE-rate (MACE = Major Adverse Cardiac Events) was 13.4% (two cardiac death; five Q-wave/nine non-Q-wave myocardial infarctions (MI); nine CABG and 32 target lesion revascularization (TLR), which is similar to the calculated 15% MACE-rate in comparable reference studies. Secondary end-points included among others restenosis at six months in the SOPHOS A population. The target vessel diameter was 2.98 +/- 0.48 mm. Minimal lumen diameter pre/post procedure and at follow-up was 1.00 +/- 0.32, 2.69 +/- 0.37, 1.91 +/- 0.71 mm, respectively. The binary restenosis rate (>/=50% diameter stenosis at follow-up) was 17.7%. CONCLUSION: The coronary BiodivYsio stent is safe and effective as a primary device for the treatment of native coronary artery lesions in patients with stable or unstable angina pectoris. Clinical and angiographic results are in the statistical range of equivalence with comparable studies with other current stents.     

Involvement of matrix metalloproteinases 2 and 9, tissue inhibitor of metalloproteinases and apoptosis in tissue remodelling in the sheep placenta

Placental growth and development is crucial for successful pregnancy. The aim of this study was to characterize the activity and localization of the matrix metalloproteinase 2 (MMP-2) and MMP-9, which are capable of degrading basement membrane collagen (predominantly collagen type IV), and their endogenous tissue inhibitor of matrix metalloproteinases (TIMPs), in amniotic fluid and in the developing ovine placenta. Cell deletion by apoptosis during placental development was also examined. Zymography with gelatin as substrate indicated that MMP-2 (72 kDa gelatinase A; predominantly latent form) was present in increasing amounts in amniotic fluid from day 70 of gestation to labour (days 140-145), and MMP-9 (92 kDa gelatinase B; predominantly latent form) was detectable from day 125 to labour; there was no increase in MMP-2 or -9 in labour. A broad range of TIMPs was detected in amniotic fluid; the molecular masses corresponded to TIMP-1, -2 and -3. Immunohistochemical techniques localized MMP-2, MMP-9 and TIMP-3 in the sheep placenta, predominantly in the trophoblast layer in uninucleate, but not binucleate, cells. However, MMP-2 and -9 activated proteins in placental homogenates were low throughout pregnancy. Apoptosis was identified by morphological criteria and also by TdT-mediated dUTP nick end labelling. Apoptosis was present in discrete regions in the placenta, predominantly in trophoblast cells near the tips and the basal regions of the fetomaternal interdigitations. During pregnancy the sheep placenta becomes more complex and the area of the fetomaternal interface increases. MMP-2 and -9 are likely to be involved in breaking down basement membranes to allow cell migration during this process. It is suggested that digestion of supporting extracellular matrix may trigger apoptosis and in some way increase the branching pattern in the villi.     

Biological and molecular characterizations of Toxoplasma gondii strains obtained from southern sea otters (Enhydra lutris nereis)

Toxoplasma gondii was isolated from brain or heart tissue from 15 southern sea otters (Enhydra lutris nereis) in cell cultures. These strains were used to infect mice that developed antibodies to T. gondii as detected in the modified direct agglutination test and had T. gondii tissue cysts in their brains at necropsy. Mouse brains containing tissue cysts from 4 of the strains were fed to 4 cats. Two of the cats excreted T. gondii oocysts in their feces that were infectious for mice. Molecular analyses of 13 strains indicated that they were all type II strains, but that they were genetically distinct from one another.     

A laser-based method for measuring thermal nociception of cattle

We describe a method for measuring nociception in cattle using a CO(2) laser aimed at the caudal aspect of the metatarsi. In Experiment 1, infrared thermography showed that calves responded by lifting their legs when skin temperatures reached 45-55 degrees C. In Experiment 2a, the validity of the method was tested by comparing the response latencies of 14 calves to two power settings (2.25 W vs. 4.5 W) with each setting being applied six times. We found that both leg-lift latencies and tail-flick latencies were lower at the higher power setting, and the calves were more likely to respond by kicking than by simply moving the leg. The standard deviations between and within calves were smaller at the higher power setting, and the large within-calf variation means that at least three tests were required to obtain reliable measures that could differentiate between calves. In Experiment 2b, application of the laser at a range of power settings (2.0, 3.0, 4.0, 4.5, 5.0 and 5.5 W) on 16 calves showed that response latencies decreased as power increased up to 4.5 W, after which no further change occurred. In Experiment 3, the repeatability of the method was evaluated on nine measures with the high power setting (4.5 W). The coefficient of variation associated with repetition of the measures was 36%. In general, we found little change in response latencies with repeated use of the laser, except that responses on the second test tended to be shorter. Experiment 4 showed that ambient temperatures between 16 degrees C and 27 degrees C did not affect response latencies, but these were longer at temperatures of 7 degrees C. We suggest that the method is a useful way of measuring cattle's sensitivity to nociception as the animals need not be restrained and the distance to the animal need not be closely controlled. However, to obtain accurate, valid and reliable measures it is necessary to use a high power setting (4.5 W) and take at least three consecutive measures of the response latency.     

Neospora caninum:Tachyzoites Express a Potent Type-I Nucleoside Triphosphate Hydrolase,but Lack Nucleoside Diphosphate Hydrolase Activity

Asai, T., Howe, D. K., Nakajima, K., Nozaki, T., Takeuchi, T., and Sibley, L. D.Neospora caninum: Tachyzoites Express Type-I Nucleoside Triphosphate Hydrolase1. But Lack Nucleoside Diphosphate Hydrolase Activity.Experimental Parasitology90,277–285. We have identified type I nucleoside triphosphate hydrolase (NTPase; EC 3.6.1.3) activity, previously thought to be restricted to the virulent strains ofToxoplasma gondii, in the cell extracts ofNeospora caninumtachyzoites. Sequence analysis of a complete cDNA from Nc-1 strain indicated thatN. caninumNTPases shared approximately 69% identity to the NTPases ofT. gondiiand are most similar to the NTPase-I isozyme. Southern blot analysis of genomic DNA and sequence analysis of two independentNTPclones from the Nc-1 strain revealed the presence of multiple genes, at least two of which are transcribed. Substrate specificity andK_mvalues for MgATP²⁻and MgADP⁻hydrolysis for recombinant or partially purified native NcNTPase were the same as those for the type I isozyme (NTPase-I). Significantly, no type II enzyme (NTPase-II) activity for NDP hydrolysis was detected in cell extracts ofN. caninum, although it is universally present in allT. gondiistrains that have been tested. This intriguing difference between these two closely related apicomplexan parasites may provide insight into the function of the NTPases during intracellular parasitism.     

Identification of Highly Attenuated Mutants of Simian Immunodeficiency Virus

Deletion mutants of the pathogenic clone of simian immunodeficiency virus isolate 239 (SIVmac239) were derived that are missing nef, vpr, and upstream sequences (US) in the U3 region of the LTR (SIVmac239Δ3), nef, vpx, and US (SIVmac239Δ3x), and nef, vpr, vpx, and US (SIVmac239Δ4). These multiply deleted derivatives replicated well in the continuously growing CEMx174 cell line and were infectious for rhesus monkeys. However, on the basis of virus load measurements, strength of antibody responses, and lack of disease progression, these mutants were highly attenuated. Measurements of cell-associated viral load agreed well with assays of plasma viral RNA load and with the strengths of the antibody responses; thus, these measurements likely reflected the extent of viral replication in vivo. A derivative of SIVmac239 lacking vif sequences (SIVmac239Δvif) could be consistently grown only in a vif-complementing cell line. This Δvif virus appeared to be very weakly infectious for rhesus monkeys on the basis of sensitive antibody tests only. The weak antibody responses elicited by SIVmac239Δvif were apparently in response to low levels of replicating virus since they were not elicited by heat-inactivated virus and the anti-SIV antibody responses persisted for greater than 1 year. These results, and the results of previous studies, allow a rank ordering of the relative virulence of nine mutant strains of SIVmac according to the following order: Δvpr > Δvpx > ΔvprΔvpx Δnef > Δ3 > Δ3x ≥ Δ4 > Δvif > Δ5. The results also demonstrate that almost any desired level of attenuation can be achieved, ranging from still pathogenic in a significant proportion of animals (Δvpr and Δvpx) to not detectably infectious (Δ5), simply by varying the number and location of deletions in these five loci.     

Spectrometric studies on stability of tenuazonic acid (TeA) solution in organic solvents

The stability of tenuazonic acid solution at different temperatures and storage times was studied using methanol, methanol-water (8:2 v/v), benzene and benzene-acetonitrile (98:2 v/v) as solvents. Solutions were analysed by a spectrometric method TeA U.V.-spectrum was recorded. Results indicated that the optimum temperature for long-time storage period of tenuazonic acid solution in any solvent assayed is -20°C. Benzene and benzene-acetonitrile (98:2 v/v) could be advised to make tenuazonic acid solution which will be stored less than 2 months at 4°C. Methanol and methanolwater (8:2 v/v) are not recommended because a low stability of TeA solution in this solvents.     

A High Power‐Density,Mediator‐Free,Microfluidic Biophotovoltaic Device for Cyanobacterial Cells

Biophotovoltaics has emerged as a promising technology for generating renewable energy because it relies on living organisms as inexpensive, self‐repairing, and readily available catalysts to produce electricity from an abundant resource: sunlight. The efficiency of biophotovoltaic cells, however, has remained significantly lower than that achievable through synthetic materials. Here, a platform is devised to harness the large power densities afforded by miniaturized geometries. To this effect, a soft‐lithography approach is developed for the fabrication of microfluidic biophotovoltaic devices that do not require membranes or mediators. Synechocystis sp. PCC 6803 cells are injected and allowed to settle on the anode, permitting the physical proximity between cells and electrode required for mediator‐free operation. Power densities of above 100 mW m^‐2 are demonstrated for a chlorophyll concentration of 100 μM under white light, which is a high value for biophotovoltaic devices without extrinsic supply of additional energy.     

2-O Heparan Sulfate Sulfation by Hs2st Is Required for Erk/Mapk Signalling Activation at the Mid-Gestational Mouse Telencephalic Midline

Heparan sulfate (HS) is a linear carbohydrate composed of polymerized uronate-glucosamine disaccharide units that decorates cell surface and secreted glycoproteins in the extracellular matrix. In mammals HS is subjected to differential sulfation by fifteen different heparan sulfotransferase (HST) enzymes of which Hs2st uniquely catalyzes the sulfation of the 2-O position of the uronate in HS. HS sulfation is postulated to be important for regulation of signaling pathways by facilitating the interaction of HS with signaling proteins including those of the Fibroblast Growth Factor (Fgf) family which signal through phosphorylation of extracellular signal-regulated kinases Erk1/2. In the developing mouse telencephalon Fgf2 signaling regulates proliferation and neurogenesis. Loss of Hs2st function phenocopies the thinned cerebral cortex of mutant mice in which Fgf2 or Erk1/2 function are abrogated, suggesting the hypothesis that 2-O-sulfated HS structures play a specific role in Fgf2/Erk signaling pathway in this context in vivo. This study investigated the molecular role of 2-O sulfation in Fgf2/Erk signaling in the developing telencephalic midline midway through mouse embryogenesis at E12.5. We examined the expression of Hs2st, Fgf2, and Erk1/2 activity in wild-type and Hs2st^-/- mice. We found that Hs2st is expressed at high levels at the midline correlating with high levels of Erk1/2 activation and Erk1/2 activation was drastically reduced in the Hs2st^-/- mutant at the rostral telencephalic midline. We also found that 2-O sulfation is specifically required for the binding of Fgf2 protein to Fgfr1, its major cell-surface receptor at the rostral telencephalic midline. We conclude that 2-O sulfated HS structures generated by Hs2st are needed to form productive signaling complexes between HS, Fgf2 and Fgfr1 that activate Erk1/2 at the midline. Overall, our data suggest the interesting possibility that differential expression of Hs2st targets the rostral telencephalic midline for high levels of Erk signaling by increasing the sensitivity of cells to an Fgf2 signal that is rather more widespread.