bluuebunny/crossref_metadata_2025 huggingface dataset:
On new experimental data manifesting the time resonances (or explosions)
Authors: Olkhovsky Vladislav , Dolinska Marina , Omelchenko Sergey
Published: February 2011

Some new applications of the time resonances (explosions) to new experimental data on high-energy nuclear processes are presented. These new experimental data are fitted rather well by the approach of the time resonances for the compound nuclei and clots.
Drought tolerance in cereals in terms of water retention, photosynthesis and antioxidant enzyme activities
Authors: Bencze Szilvia , Bamberger Zsuzsanna , Janda Tibor , Balla Krisztina , Bedő Zoltán , Veisz Ottó
Published: February 2011

Experiments were carried out on three bread wheat varieties, one barley and one durum wheat variety grown in pots in the phytotron and subjected to water withdrawal for 7 days during grain-filling. Leaf water loss, net assimilation rate and transpiration showed marked differences, allowing the genotypes to be ranked. Although the most resistant variety had the highest activity for ascorbate peroxidase (APX), catalase (CAT), glutathione reductase (GR) and glutathione-S-transferase (GST), which did not rise further in response to drought and the most susceptible variety had the lowest values, which increased to the greatest extent under drought, the level of sensitivity could not be predicted for all the genotypes from the enzyme activity values alone. The largest increases were recorded for the APX, CAT and GR activities. In most genotypes the GR activity was correlated with that of GST, CAT and APX. Changes in the enzyme activities were observed after a decline in transpiration and photosynthesis. The range of soil moisture values over which the antioxidant enzyme activity levels remained relatively unchanged was a better indication of tolerance to drought than either basic or stress-induced activity levels.
Solubility of methane in pure non-ionic surfactants and pure and mixtures of linear alcohols at 298 K and 101.3 kPa
Authors: García-Aguilar Balbina , Ramirez Antonio , Jones J. , Heitz Michèle
Published: February 2011

The emissions of methane (CH4), a powerful greenhouse gas (GES), contribute to the increase in GES concentration level in the atmosphere. For this reason, the importance of controlling CH4 emissions of anthropogenic origin has increased over the last decades. Physicochemical and biological processes are available for treating CH4. For this reason, such properties as the solubility of CH4 in aqueous solutions and organic solvents are of great relevance in different applications in environmental engineering and biotechnology. In this study, the solubility of CH4 was determined at 298 K and 101.3 kPa in organic solvents, such as polyoxyethylenesorbates (Tween 20, Tween 40, and Tween 60), and linear alcohols (methanol, ethanol, and butan-1-ol) alone and in their admixtures. Admixtures of methanol with butan-1-ol exhibited the highest solubility of CH4, of around 0.49 g m−3 of solvent, whereas the solubility of CH4 in linear alcohols varied from 0.167 g m−3 to 0.41 g m−3 of solvent. In the case of Tweens, CH4 solubility decreased with the hydrophilic-lipophilic balance (HLB) number.
Pd-catalysed conjugate addition of arylboronic acids to α,β-unsaturated ketones under microwave irradiation
Authors: Poláčková Viera , Bariak Vladimír , Šebesta Radovan , Toma Štefan
Published: February 2011

The Pd-catalysed conjugate addition of arylboronic acids to α,β-unsaturated cyclic ketones was studied under controlled microwave irradiation conditions. A variety of catalysts, bases and solvents was explored in order to achieve optimum yields in the shortest possible reaction time. Under optimised conditions (Pd(OAc)2/2,2′-bipyridine and KF in a mixture of toluene, water, and acetic acid and 10 min microwave irradiation), a range of arylboronic acids was successfully added to several cyclic enones. With chiral phosphane ligands, a promising enantioselectivity was obtained (85 % ee).
The Use of Selenium Enriched Enterococcus faecium as an Alternative Selenium Source for Growing-finishing Pigs
Authors: Svoboda Martin , Fajt Zdeněk , Baňoch Tomáš , Drábek Josef , Saláková Alena
Published: February 2011

The aim of the study was to evaluate the effect of the feeding of selenium enrichedEnterococcus faeciumon selenium concentrations in muscle tissue and on meat quality indicators in finishing pigs. Groups of pigs fed Se-enrichedE. faecium(n = 12), sodium selenite (n = 12) and Se-enriched yeast (n = 12) were used in the study. The tested feed mixtures were fed for a period of 3 months before the pigs were slaughtered. The selenium concentrations in muscle tissue achieved by the use of Se-enrichedE. faeciumwere comparable to those achieved in sodium selenite diets and lower (p≤ 0.05) compared to Se-enriched yeast. Concentration of Se in serum and glutathione peroxidase (GSH-Px) activities did not differ in animals fed different Se forms. No differences in indices of meat quality were found among the groups. Se-enrichedE. faeciumbacteria can be recommended as an alternative selenium source for finisher pigs with the similar efficacy as sodium selenite.
The Effect of Probiotics on the Morphological Characteristics of the Small Intestinal Mucosa
Authors: Rekiel Anna , Bielecki Wojciech , Więcek Justyna
Published: February 2011

The objective of this study was to determine the impact of antibiotics and selected probiotics on the morphological properties of the small intestinal mucosa in growing-finishing pigs. Two production experiments were conducted on 32 hybrid fatteners (16 pigs per experiment, of 8 gilts and young hogs each, at a 1:1 ratio) fed complete diets in a 2-phase system. The animals were clinically healthy and had been treated for parasites prior to fattening. In the first experiment, diets were supplemented with the antibiotic flavomycin (group C1) and the probiotic ToyoCerin (Bacillus toyoi strain) (group E1) at the amount of 0.1%, and in the second experiment with flavomycin (C2) and Bactocell (Pedicoccus acidilactici, MA18/5M strain) (E2) at the amount of 0.01%. A histological analysis of small intestinal epithelial sections was performed using bax, bcl-x, bcl-2 polyclonal antibodies and Ki-67 and PCNA monoclonal antibodies. Sections of the duodenum, jejunum and ileum were prepared post mortem. Haematoxylin and eosin H-E, histochemical (PAS-Alcian Blue) and immunohistochemical staining procedures were applied. The results of histological, histochemical and immunohistochemical examinations of the small intestinal mucosa indicated that feed additives and probiotics had a varied effect on the morphological characteristics and the proliferation capacity of crypt epithelium. Enterocyte proliferation in crypt epithelium decreased after the administration of probiotics. The absence of significant differences between groups (C1-E1; C2-E2) may suggest that probiotics have no adverse effect on mucosal epithelial cells. Nevertheless, given the importance of this topic and the development of the use of feed additives, follow up research in this area is needed.
The Effect of Soybean-Derived Phytoestrogens on Concentrations of Plasma Isoflavones, 15-keto-13,14-dihydroprostaglandin F2α and Progesterone in Dairy Cows
Authors: Watzková Jarmila , Křížová Ludmila , Pavlík Aleš , Schulzová Věra , Hajšlová Jana , Lojza Jaromír
Published: February 2011

The objective of the study was to determine the effect of soybean-derived phytoestrogens and their metabolites on the activity of sex hormones during the oestrous cycle in multiparous lactating dairy cows. The experiment was carried out on 4 multiparous lactating Holstein cows in the form of replicated Latin square in double reversal design. The experiment in the total length of 168 days was divided into 4 periods of 42 days, each consisting of a 21-day preliminary period and a 21-day collecting period. Cows were divided into 2 groups of 2 cows. The control group (C) was fed a diet based on extruded rapeseed cake while the experimental group (S) was fed a diet containing extruded full-fat soya. The intake of total isoflavones was 3297 mg/d in S and 58.0 mg/d in C (P < 0.001). The concentrations of individual isoflavones, it is daidzein, genistein and equol in plasma were significantly higher in the experimental group S (49.3, 78.7 and 218.8 ng/ml, respectively) than in the control group C (13.5, 42.9 and 18.3 ng/ml, respectively, P < 0.001). Plasma concentration of progesterone throughout the oestrous cycle was not influenced by the diet used (P > 0.05). Plasma concentration of prostaglandine PGFM throughout the oestrous cycle in the experimental group (S) tended to be higher (P = 0.095) than in the control group (C). No differences in the length of the oestrous cycle between the cows fed different diets were observed.
Effect of Propolis on the Fish Muscular Development and Histomorphometrical Characteristics
Authors: Velotto Salvatore , Vitale Claudia , Varricchio Ettore , Crasto Antonio
Published: February 2011

The aim of our study was to evaluate the effect of propolis on mortality of fish eggs due to mycosis, to study its efficacy on the fish growth rate and to analyze the histochemical and ultrastructural characteristics of muscle fibres. We evaluated the muscular development of fish in two different experimental conditions: traditional feeding and feeding with addition of propolis(groups A and B, respectively). The study was carried out on two species of teleosts bred in Italy,Oncorhynchus mykiss(rainbow trout) andSalmo trutta(brown trout). The use of propolis reduced mortality of fish eggs. The muscles were stained for myosin ATPase and succinic dehydrogenase to evaluate fibre type. The area, maximum and minimum diameter for each fibre type in relation to the body length were measured. The animals fed propolis showed a more rapid muscular growth compared to control fed the standard diet. Fibres were larger in the Salmo trutta than in the Oncorhynchus mykiss in both groups. In fish of A group, myotomal muscle, the presence of giant fibres and index of environmental stress was noticed. This type of study is valuable in order to extend the use of propolis as an antifungal agent and a natural product that can improve fish farming.
Chemical Composition of Fillets of Mirror Crossbreds Common Carp (Cyprinus carpio L.)
Authors: Buchtová Hana , Svobodová Zdeňka , Kocour Martin , Velíšek Josef
Published: February 2011

This paper presents the results of a study dealing with chemical composition of fillets and fatty acid composition (saturated fatty acid: SFA, monounsaturated fatty acid: MUFA, polyunsaturated fatty acid: PUFA) of lipids. Three groups of the mirror hybrid carp in age of three years: M2 × L15 – the Hungarian Szarvas mirror carp (M2) and the Hungarian hybrid mirror strain (L15), M2 × DOR 70 (the Israeli breed - DOR70), M2 × M72 (Northern mirror carp - M72) were compared with: the pure breed M2 and scaly hybrid ROP × TAT – the Ropsha (ROP) and the Tata (TAT) carp. ROP × TAT hybrid fillets contained (in g·kg-1) more (P< 0.01) dry matter (283.1 ± 23.87) and lipids (99.3 ± 30.60). Fat in all of the monitored carp groups was made up of more than 50% of MUFA (from 51 to 64%), 25 - 29% of SFA and 10 - 22% of PUFA. Fillets of mirror hybrids M2 × DOR70, M2 × M72 and breed M2 contained less lipids (P< 0.01), less MUFAsum(P< 0.01), particularly less oleic acid (C18:1n-9), and more PUFAn-3(P< 0.01), more eicosapentaenoic acid (C20:5n-3) and docosahexaenic acid (C22:6n-3). The differences in fatty acid profile can be related to the different genetic effects of different groups of common carp.
The Influence of Interleukin (IL)-1β and IL-6 and Tumour Necrosis Factor-α on Prostaglandin Secretion from Porcine Myometrium during the First Third of Pregnancy
Authors: Jana Barbara , Koszykowska Marlena , Andronowska Aneta
Published: February 2011

The present study was undertaken to determine the effect of interleukin-1β (IL-1β), interleukin-6 (IL-6) and tumour necrosis factor-α (TNF-α) on prostaglandin (PG)F2αand PGE2secretion as well as cyclooxygenase-2 (COX-2) protein expression in myometrium collected on days 25, 30 and 40 of pregnancy in pigs. Myometrial slices were incubated for 16 h with IL-1β, IL-6 and TNF-α (1 or 10 ng/ml of medium) or two combinations of the three cytokines (1 or 10 ng/ml of each cytokine per combination). We demonstrated the stimulatory effect of IL-1β and IL-6 on PGF2αand PGE2secretion from myometrium collected on all examined days of pregnancy, excepting of influence of IL-6 on release of PGF2αby tissue from day 30. In turn, TNF-α was able to stimulate only PGE2secretion by myometrium of 40-day-pregnant gilts. The three cytokines applied in combination augmented release of PGE2from myometrium collected on days 30 and 40 of pregnancy. Stimulation of PGE2secretion by cytokines used individually was more frequent than that of PGF2α. Moreover, an enhancement in PGF2αand/or PGE2release was accompanied by an increase of COX-2 protein expression. Our study shows the ability of cytokines to stimulate PGF2αand PGE2release by porcine myometrium from the first third of pregnancy. Obtained data suggest that locally PGs produced in myometrium influencing the uterine contraction activity may be important for the maintenance of myometrial quiescence during pregnancy and confirm also that the complex cytokine network is an important regulatory mechanism of PGs production during pregnancy.
Purine Turnover Metabolites and Selected Antioxidants in Blood of Goats during the Periparturient Period
Authors: Skotnicka Ewa , Baranowska-Bosiacka Irena , Dudzińska Wioleta , Suska Maria
Published: February 2011

The aim of this study was to examine the relationships between the erythrocyte concentrations of ATP, ADP, AMP, NAD+, NADP+ and adenylate energy charge (AEC) and their metabolites: inosine (Ino), hypoxanthine (Hyp), uric acid (UA), selected blood antioxidants: superoxide dismutase (SOD), glutathione reductase (GR) of goats during the periparturient period. The study was conducted on 12 clinically healthy pregnant goats (Capra hircus) - 75% genotype of the Polish noble white aged between 2-3 years. Blood was taken from the external jugular vein early in the morning before feeding and obtained twice (4 weeks and 1 week) before delivery and twice (2 and 3 weeks) after delivery. The ATP concentration did not change significantly. One week before delivery ADP, AMP and Ino concentrations were significantly higher and AEC value significantly lower compared to values in the third week after delivery (p ≤ 0.02, p ≤ 0.05, p ≤ 0.03 and p ≤ 0.01, respectively). One week before and two weeks after delivery we observed a significant increase in SOD and GR activities and an increase in NAD+ and NADP+ concentrations but a significant decrease in Hyp and UA concentrations. Constant ATP concentration and the changes in the dynamics and tendency of Hyp and UA concentrations show that in the periparturient period in goats, purine metabolism undergoes adaptive changes. The balance between resynthetic processes and adenine nucleotide degradation is retained in order to level the oxygen and energy lacks. The results of our study show that the maintenance of prooxidative homeostasis in goats of peripartal period depends mainly on enzymatic mechanisms.
Acute Toxicity of the Preparation PAX-18 for Juvenile and Embryonic Stages of Zebrafish (Danio rerio)
Authors: Mácová Stanislava , Plhalová Lucie , Široká Zuzana , Doleželová Petra , Pištěková Vladimíra , Svobodová Zdeňka
Published: February 2011

The preparation PAX-18 is a coagulation agent, which is used in water and wastewater treatment facilities and for the treatment of natural waters. The active compound is polyaluminium chloride (9% of Al). The application to the water environment could present a potential risk to different developmental stages of fish. The aim of this study was to assess and compare the toxicity of the preparation PAX-18 for embryonic and juvenile developmental stages of zebrafish (Danio rerio). The acute toxicity tests with juvenile fish aged 2–3 months were conducted according to the method OECD No. 203 in 5 series. For embryo toxicity test the method OECD No. 212 was used in 5 series. The semistatic methods were selected. The results of toxicity tests (the number of dead individuals at particular test concentrations) were subjected to probit analysis using the EKO-TOX 5.2 programme to determine LC50 values of PAX. The LC50 mean value of PAX for juvenile D. rerio was 749.7 ± 30.6 mg·l-1 (67.5 ± 2.8 mg·l-1 of Al) and 731.5 ± 94.1 mg·l-1 (65.8 ± 8.5 mg·l-1 of Al) for embryonic stages of D. rerio. The sensitivity of juvenile and embryonic stages to PAX were comparable (p > 0.01). The acute toxicity values of PAX-18 found in tests on D. rerio were 6–13 × higher than the concentration which is usually applied to waters (5–10 mg·l-1 of Al). Therefore, the acute toxicity effect on fish can be considered minimal.
Comparison of Terbutryn Acute Toxicity to Danio rerio and Poecilia reticulata
Authors: Plhalová Lucie , Mácová Stanislava , Doleželová Petra , Maršálek Petr , Svobodová Zdeňka , Pištěková Vladimíra , Bedáňová Iveta , Voslářová Eva , Modrá Helena
Published: February 2011

The aim of the present study was to determine and compare acute toxicity of terbutryn in Danio rerio and Poecilia reticulata, and in two different developmental stages of D. rerio – embryonic and juvenile. Acute toxicity tests were performed according to OECD methodology. The LC50 values were assessed by probit analysis using EKO-TOX 5.2 programme. The 96hLC50 terbutryn mean value of 5 tests was 2.85 ± 0.75 mg·l-1 for the juvenile stage of P. reticulata and 5.71 ± 0.46 mg·l-1 for the juvenile stage of D. rerio. For the embryonic stage of D. rerio the 144hLC50 terbutryn mean value of 6 tests was estimated as 8.04 ± 1.05 mg·l-1. The study proved significantly higher (p < 0.01) sensitivity of the juvenile stage of D. rerio to terbutryn compared to the embryonic stage of D. rerio and significantly higher (p < 0.01) sensitivity of the juvenile stage of P. reticulata to terbutryn compared to the juvenile stage of D. rerio. herbicides. This study documented differences in sensitivity of several fish species and different developmental stages of fish to one of triazine.
Radiographic Assessment of Implant Failures of Titanium 3.5 LCP vs. 4.5 LCP Used for Flexible Bridging Osteosynthesis of Large Segmental Femoral Diaphyseal Defects in a Miniature Pig Model
Authors: Nečas Alois , Proks Pavel , Urbanová Lucie , Srnec Robert , Stehlík Ladislav , Crha Michal , Raušer Petr , Plánka Ladislav , Amler Evžen , Vojtová Lucy , Jančář Josef
Published: February 2011

The study describes types, absolute and relative numbers of implant failures in flexible bridging osteosynthesis using a six-hole 3.5 mm titanium Locking Compression Plate (n = 9) or a five-hole LCP 4.5 mm titanium (n = 40) selected for the fixation of segmental ostectomy of femoral diaphysis in the miniature pig used as anin vivomodel in a study on the healing of a critically sized bone defect using transplantation of mesenchymal stem cells combined with biocompatible scaffolds within a broader research project. Occasional implant failure was evaluated based on radiographic examination of femurs of animals 2, 4, 8, 12 and 16 weeks after surgery. When bone defect was stabilized using 3.5 mm LCP, in 6 cases (66.7%) the screw was broken/lost in the proximal fragment of the femur 2 weeks after implantation (n = 4) and 4 weeks after implantation (n = 2). In 4 cases of these, the implant failure was accompanied also by loosening of the screw in position 3 in the proximal fragment of the femur. During ostectomy stabilization with 4.5 mm LCP, in 3 cases (7.5%) LCP was broken at the place of the empty central plate hole (without inserted screw) at the level of the segmental bone defect. Compared to the six-hole 3.5 mm LCP, the five-hole titanium 4.5 mm LCP is more suitable implant for flexible bridging osteosynthesis of a critically sized segmental defect of femoral diaphysis in the miniature pig. The results of this study will allow reducing implant failures in time- and cost-demanding transplantation experiments focused on bone healing.
Healing of Large Segmental Bone Defect after Implantation of Autogenous Cancellous Bone Graft in Comparison to Hydroxyapatite and 0.5% Collagen Scaffold Combined with Mesenchymal Stem Cells
Authors: Nečas Alois , Proks Pavel , Urbanová Lucie , Srnec Robert , Stehlík Ladislav , Crha Michal , Raušer Petr , Plánka Ladislav , Janovec Jan , Dvořák Milan , Amler Evžen , Vojtová Lucy , Jančář Josef
Published: February 2011

At present, attention is focused on research into possibilities of healing large bone defects by the method of mini-invasive osteosynthesis, using implantation of biomaterials and mesenchymal stem cells (MSCs). This study evaluates the healing of segmental femoral defects in miniature pigs based on the radiological determination of the callus: cortex ratio at 16 weeks after ostectomy. The size of the formed callus was significantly larger (p< 0.05) in animals after transplantation of an autogenous cancellous bone graft (group A, callus : cortex ratio of 1.77 ± 0.33) compared to animals after transplantation of cylindrical scaffold from hydroxyapatite and 0.5% collagen (group S, callus : cortex ratio of 1.08 ± 0.13), or in animals after transplantation of this scaffold seeded with MSCs (group S + MSCs, callus: cortex ratio of 1.15 ± 0.18). No significant difference was found in the size of callus between animals of group S and animals of group S + MSCs. Unlike a scaffold in the shape of the original bone column, a freely placed autogenous cancellous bone graft may allow the newly formed tissue to spread more to the periphery of the ostectomy defect. Implanted cylindrical scaffolds (with and without MSCs) support callus formation directly in the center of original bone column in segmental femoral ostectomy, and can be successfully used in the treatment of large bone defects.
Comparison of the Resistance to Bending Forces of the 4.5 LCP Plate-rod Construct and of 4.5 LCP Alone Applied to Segmental Femoral Defects in Miniature Pigs
Authors: Urbanová Lucie , Srnec Robert , Proks Pavel , Stehlík Ladislav , Florian Zdeněk , Návrat Tomáš , Nečas Alois
Published: February 2011

The study deals with the determination of mechanical properties, namely resistance to bending forces, of flexible buttress osteosynthesis using two different bone-implant constructs stabilizing experimental segmental femoral bone defects (segmental ostectomy) in a miniature pigex vivomodel using 4.5 mm titanium LCP and a 3 mm intramedullary pin (“plate and rod” construct) (PR-LCP), versus the 4.5 mm titanium LCP alone (A-LCP). The “plate and rod” fixation (PR-LCP) of the segmental femoral defect is significantly more resistant (p< 0.05) to bending forces (200 N, 300 N, and 500 N) than LCP alone (A-LCP). Stabilisation of experimental segmental lesions of the femoral diaphysis in miniature pigs by flexible bridging osteosynthesis 4.5 mm LCP in combination with the “plate and rod” construct appears to be a suitable fixation of non-reducible fractures where considerable strain of the implants by bending forces can be assumed. These findings will be used in upcomingin vivoexperiments in the miniature pig to investigate bone defect healing after transplantation of mesenchymal stem cells in combination with biocompatible scaffolds.
Dog Bites to Children in the Czech Republic: the Risk Situations
Authors: Náhlík Jan , Baranyiová Eva , Tyrlík Mojmír
Published: February 2011

The aim of this study was to analyse dog bites to children in the Czech Republic. Data were obtained from a questionnaire completed with children aged 4 to 13 years in 11 urban and rural primary schools. A total of 103 dog bites sustained by 92 children were analysed using chi square test and F test. There were 58 boys (56.3%) and 45 girls (43.7%) bitten, 57.3% of them once, 42.7% repeatedly. The evaluated answers showed that children were bitten when playing with own dogs (69.2%) or dogs known to them (30.8%) but not by unknown dogs (χ2= 25.397, df = 1,p< 0.001). Children were bitten outdoors by loose running unknown dogs (88.5%), known dogs (11.5%) but not by own dogs (χ2= 55.528, df = 2,p< 0.001). Thirty-two children were bitten indoors by small (53.1%), medium size (21.9) or large (25.0%) dogs. Small dogs were biting mostly indoors (51.5%), medium size (73.1%) and large (80.5%) dogs bit mostly outdoors (χ2= 9.0022, df = 2,p= 0.011). Most of the children that disturbed a resting or sleeping dog were bitten indoors (83.3%; χ2= 7.862, df = 1,p< 0.01), predominantly by small dogs (83.3%, χ2= 7.482, df = 2,p= 0.022). When stroking a dog, children were bitten by a medium size (45.5%), large (31.8%) or small dog (22.7%; χ2= 5.588, df = 2,p< 0.068). Children injured by their family-owned dog had accidentally caused pain to it before being bitten (83.3%; χ2= 7.862, df = 1,p< 0.012).These children were always bitten by a small dog (χ2= 7.482, df = 2,p= 0.022). Three children reported deliberately causing pain to a dog – these were all small dogs (100.0%; χ2= 6.279, df = 2,p< 0.05). Children teasing dogs were bitten most frequently by a small dog (75.0%; χ2= 6.98, df = 2,p< 0.032). Male dogs bit more frequently (66.7%) than females (33.3%; χ2= 6.338, d.f. =1,p= 0.014). These data were the first ones obtained from the bitten children. They suggest that in interactions with own, known and small dogs, children were more daring. The personal space of dogs, their warning signals, and defence were underestimated, the resulting aggression was mostly of possessive, territorial and fear type. Additional suggestions are made to complete the information on preventive measures for parents, children and the public. Importantly, all information types should point out that the dog remains a predator despite its long domestication history and close co-existence with humans.
Periodontal Health vs. Various Preventive Means in Toy Dog Breeds
Authors: Capík Igor
Published: February 2011

This study used six toy Chihuahua dogs in relationship. They underwent four 8 week periods differing in type of food (dry, soft, dental diet) and preventive means of periodontitis (tooth-brushing and enzymatic chewing strips). The results showed nonsignificant influence of food consistency on dental plaque, calculus and gingivitis scores. Dental diet nonsignificantly decreased dental calculus deposition in comparison to common commercial food. The best results were achieved with toothbrushing. The enzymatic chewing strips significantly decreased dental plaque, calculus and gingivitis scores only on carnassial teeth. These results confirm that there are no absolute preventive measures of periodontitis.
Ras Isoprenylation and pAkt Inhibition by Zoledronic Acid and Fluvastatin Enhances Paclitaxel Activity in T24 Bladder Cancer Cells
Authors: Li Shaojuan , De Souza Paul
Published: February 2011

Background: Bisphosphonates interfere with the mevalonate pathway and inhibit the prenylation of small GTP-binding proteins such as ras and rap. We hypothesized that zoledronic acid would synergistically inhibit T24 bladder cancer cell growth in combination with fluvastatin and paclitaxel. Methods: Increasing doses of fluvastatin, zoledronic acid, and paclitaxel were investigated as single agents and in combination, and synergistic interactions were evaluated by the Chou-Talalay method. Western blots were used to assess effects on signal transduction pathways. Results: Growth of T24 was significantly inhibited with IC50 values of 2.67 ± 0.61 mM for fluvastatin and 5.35 ± 1.35 mM for zoledronic acid after 72 hours treatment. Geranylgeranyl pyrophosphate and farnesyl pyrophosphate was able to block, in part, this inhibitory activity. The combinations of zoledronic acid and paclitaxel, zoledronic acid and fluvastatin, and fluvastatin and paclitaxel were all synergistic. Both fluvastatin and zoledronic acid inhibited Ras and Rap prenylation, and the phosphorylation of ERK1/2 and AKT. The degree of inhibition of phosphorylation of these key signaling transduction pathways appears to closely correlate with their synergistic interactions. Conclusions: Zoledronic acid enhances fluvastatin and paclitaxel activity against T24 in a synergistic manner and this is mediated largely by inhibition of both the Ras/Raf/MEK/ERK and PI3K/AKT signaling pathways via isoprenylation inhibition.
Microcanonical Description of (Micro) Black Holes
Authors: Casadio Roberto , Harms Benjamin
Published: February 2011

The microcanonical ensemble is the proper ensemble to describe black holes which are not in thermodynamic equilibrium, such as radiating black holes. This choice of ensemble eliminates the problems, e.g., negative specific heat (not allowed in the canonical ensemble) and loss of unitarity, encountered when the canonical ensemble is used. In this review we present an overview of the weaknesses of the standard thermodynamic description of black holes and show how the microcanonical approach can provide a consistent description of black holes and their Hawking radiation at all energy scales. Our approach is based on viewing the horizon area as yielding the ensemble density at fixed system energy. We then compare the decay rates of black holes in the two different pictures. Our description is particularly relevant for the analysis of micro-black holes whose existenceis predicted in models with extra-spatial dimensions.
Numerical Analysis on Gas Production Efficiency from Hydrate Deposits by Thermal Stimulation: Application to the Shenhu Area, South China Sea
Authors: Su Zheng , Cao Yuncheng , Wu Nengyou , He Yong
Published: February 2011

Gas hydrates have been attracted a great deal of attention because of their potential as an energy substitute and the climate implications. Drilling and sampling research on the hydrate deposit in the Shenhu Area on the northern continental slope of the Southern China Sea was a big breakthrough for hydrate investigation in China, but as a new potential energy source, how the gas can be effectively produced from hydrate deposits has become a hot research topic. Besides depressurization heat stimulation is regarded as another important means for producing hydrate-derived gas, however, the production efficiency and economic feasibility of producing gas by heat stimulation have not been clearly understood. In this paper, a simplified model for predicting gas production from hydrate deposits by heat stimulation is developed. The model ideally neglects the effects of heat convection and pressure regime in the sediments for simplicity. We compute the heat consumption efficiency and gas energy efficiency of gas production from hydrate deposits by heat stimulation, only considering effect of hydrate dissociation due to heat input. This model is for predicting the maximum production efficiency. By studying the hydrate reservoirs and significant parameters collected from drilling and sampling researches, we calculate the production potential of the Shenhu hydrate deposits and investigate the production efficiency and feasibility. Our research shows that the maximum amount of cumulative gas production at Shenhu is ~509 m3 per meter in three years. The production potential is much lower than the industrial criterion for marine production. In our discussion the numerical simulations show that a practical potential of the gas production is merely 25 m3/m in 3 years and contribution of thermal stimulation is very small in joint-production schemes. We conclude that production cost is quite high and the economic value of producing gas from the hydrate through a vertical well is not attractive, even though the production by heat stimulation theoretically has a very high heat consumption rate and energy efficiency.
Meiosis in a Bottle: New Approaches to Overcome Mammalian Meiocyte Study Limitations
Authors: Roig Ignasi , Brieno-Enriquez Miguel Angel , Caldes Montserrat Garcia
Published: February 2011

The study of meiosis is limited because of the intrinsic nature of gametogenesis in mammals. One way to overcome these limitations would be the use of culture systems that would allow meiotic progression in vitro. There have been some attempts to culture mammalian meiocytes in recent years. In this review we will summarize all the efforts to-date in order to culture mammalian sperm and oocyte precursor cells.
Enlightenment of Yeast Mitochondrial Homoplasmy: Diversified Roles of Gene Conversion
Authors: Ling Feng , Mikawa Tsutomu , Shibata Takehiko
Published: February 2011

Mitochondria have their own genomic DNA. Unlike the nuclear genome, each cell contains hundreds to thousands of copies of mitochondrial DNA (mtDNA). The copies of mtDNA tend to have heterogeneous sequences, due to the high frequency of mutagenesis, but are quickly homogenized within a cell (“homoplasmy”) during vegetative cell growth or through a few sexual generations. Heteroplasmy is strongly associated with mitochondrial diseases, diabetes and aging. Recent studies revealed that the yeast cell has the machinery to homogenize mtDNA, using a common DNA processing pathway with gene conversion; i.e., both genetic events are initiated by a double-stranded break, which is processed into 3' single-stranded tails. One of the tails is base-paired with the complementary sequence of the recipient double-stranded DNA to form a D-loop (homologous pairing), in which repair DNA synthesis is initiated to restore the sequence lost by the breakage. Gene conversion generates sequence diversity, depending on the divergence between the donor and recipient sequences, especially when it occurs among a number of copies of a DNA sequence family with some sequence variations, such as in immunoglobulin diversification in chicken. MtDNA can be regarded as a sequence family, in which the members tend to be diversified by a high frequency of spontaneous mutagenesis. Thus, it would be interesting to determine why and how double-stranded breakage and D-loop formation induce sequence homogenization in mitochondria and sequence diversification in nuclear DNA. We will review the mechanisms and roles of mtDNA homoplasmy, in contrast to nuclear gene conversion, which diversifies gene and genome sequences, to provide clues toward understanding how the common DNA processing pathway results in such divergent outcomes.
In Vitro and In Vivo Antioxidant Activity of a Water-Soluble Polysaccharide from Dendrobium denneanum
Authors: Luo Aoxue , Ge Zhongfu , Fan Yijun , Luo Aoshuang , Chun Ze , He XingJin
Published: February 2011

The water-soluble crude polysaccharide (DDP) obtained from the aqueous extracts of the stem of Dendrobium denneanum through hot water extraction followed by ethanol precipitation, was found to have an average molecular weight (Mw) of about 484.7 kDa. Monosaccharide analysis revealed that DDP was composed of arabinose, xylose, mannose, glucose and galactose in a molar ratio of 1.00:2.66:8.92:34.20:10.16. The investigation of antioxidant activity both in vitro and in vivo showed that DDP is a potential antioxidant.
Synthesis and Anti-Intestinal Nematode Activity of Variously Substituted Benzonaphthyridine Derivatives
Authors: Duan Li-Ping , Wen Ai-Dan , Wu Ning-Bo , Tao Yi , Zhang Hao-Bing
Published: February 2011

A series of benzonaphthyridine derivatives bearing the C=N linkage moiety were designed and synthesized. The structures of all the newly synthesized compounds were identified by elemental analysis, 1H-NMR, 13C-NMR and MS. Their anti-intestinal nematode activities against Nippostrongylus brazilliensis were evaluated in vivo by an oral route in male rats. Among these compounds, at concentrations of 10 mg/kg of rat, the compound 7-chloro-2-methoxy-10-(4-(4′-(1H-indol-5′-yl)methylene)aminophenyl)-amino-benzo[b][1,5] naphthyridine (4n) produced the highest activity, with 80.2% deparasitization. These compounds may find usefulness in the discovery and development of new anti-intestinal drugs.
Synthesis and Conformation of Substituted Chiral Binaphthyl-Azobenzene Cyclic Dyads with Chiroptical Switching Capabilities
Authors: Takaishi Kazuto , Kawamoto Masuki
Published: February 2011

Optically active binaphthyl-azobenezene cyclic dyads were synthesized to develop a photochromic switching molecule. Azobenezene moieties were cis-trans isomerized by photoirradiation. As a reflection of the structural change, the specific optical rotation and circular dichroism underwent significant shifts. Under certain conditions, the positive-negative and zero-positive (or zero-negative) signals were reversed. Optical rotation may potentially be applied in noise-cancelling nondestructive photoswiches. The conformations were studied by experimental and theoretical methods. The results revealed that the helical chirality, (P) or (M), of the cis-azobenzene moiety was induced by intramolecular axial chirality. The twist direction depended on the axial chirality as well as the azobenzene linkage position to the binaphthyls, but was independent of the identity of substituted groups. 2,2’-Linked-(R)-binaphthyl was found to induce cis-(P)-azobenzene, whereas symmetrically 7,7’-linked-(R)-binaphthyl was found to induce cis-(M)-azobenzene.
Metabolism of Zearalenone in the Course of Beer Fermentation
Authors: Mizutani Kohei , Nagatomi Yasushi , Mochizuki Naoki
Published: February 2011

Zearalenone (ZON) is a mycotoxin with estrogenic activity, produced by members of Fusarium species, and is found worldwide in a number of cereal crops. It is known to have four active metabolites (a-zearalenol (a-ZOL), b-zearalenol (b-ZOL), a-zearalanol (a-ZAL), and b-zearalanol (b-ZAL)). A highly sensitive analytical method using liquid chromatography/tandem mass spectrometry using electrospray ionization (LC-ESI-MS/MS) has been established and validated in order to analyze ZON and its metabolites in beer and malt samples. The metabolism of ZON in the course of beer fermentation was further characterized using the artificially contaminated wort by this established method. In the fermented sample, 85.9% of ZON was converted to b-ZOL, which has lower estrogenic activity than that of ZON. These findings indicate that the health risk to humans due to ZON in beer is reduced during the fermentation process.
The Inside Out of Lentiviral Vectors
Authors: Durand Stéphanie , Cimarelli Andrea
Published: February 2011

Lentiviruses induce a wide variety of pathologies in different animal species. A common feature of the replicative cycle of these viruses is their ability to target non-dividing cells, a property that constitutes an extremely attractive asset in gene therapy. In this review, we shall describe the main basic aspects of the virology of lentiviruses that were exploited to obtain efficient gene transfer vectors. In addition, we shall discuss some of the hurdles that oppose the efficient genetic modification mediated by lentiviral vectors and the strategies that are being developed to circumvent them.
Chiral recognition of macromolecules with cyclodextrins: pH- and thermosensitive copolymers from N-isopropylacrylamide and N-acryloyl-D/L-phenylalanine and their inclusion complexes with cyclodextrins
Authors: Gingter Sabrina , Bezdushna Ella , Ritter Helmut
Published: February 2011

In the present work we report the enantioselective recognition of water soluble stimuli-responsive polymers bearing phenylalanine moieties via host-guest interaction with β-cyclodextrin and randomly-methylated-β-cyclodextrin (RAMEB-CD). We synthesised N-acryloyl-D/L-phenylalanine monomers (2D, 2L) which were then copolymerised under free radical conditions with N-isopropylacrylamide (NIPAAm). The resulting copolymers 3D and 3L exhibit a lower critical solution temperature (LCST) of 25 °C. As a further benefit, the presence of a free carboxylic group in the copolymer system gives a high sensitivity to the pH value in respect to the LCST value. The enantioselective recognition of the side groups of copolymers 3D and 3L and their solubility behaviour were investigated by dynamic light scattering and 2D NMR spectroscopy, respectively.
Topical Treatment of Cutaneous Vaccinia Virus Infections in Immunosuppressed Hairless Mice with Selected Antiviral Substances
Authors: Smee Donald F , Bailey Kevin W , Wong Min-Hui , Tarbet E Bart
Published: February 2011

Background:

Certain nucleoside, nucleotide and pyrophosphate analogues may be useful for treating severe complications arising as a result of virus dissemination following smallpox (live vaccinia virus) vaccinations, especially in immunocompromised individuals. We used an immunosuppressed hairless mouse model to study the effects of 10 antiviral agents on progressive vaccinia infections.

Methods:

Hairless mice were immunosuppressed by treatment with cyclophosphamide (100 mg/kg) every 4 days starting 1 day prior to vaccinia virus (WR strain) infection of wounded skin. Topical treatments with antiviral agents were applied twice a day for 7 days starting 5 days after virus exposure.

Results:

Topical 1% cidofovir cream treatment was effective in significantly reducing primary lesion severity and decreasing the number of satellite lesions. Topical 1% cyclic HPMPC and 1% phosphonoacetic acid were not quite as active as cidofovir. Ribavirin (5%) treatment reduced lesion severity and diminished the numbers of satellite lesions, but the mice died significantly sooner than placebos. 2-Amino-7-[(1,3,-dihydroxy-2-propoxy)methyl]purine (compound S2242; 1%) moderately reduced primary lesion sizes. Ineffective treatments included 5% arabinosyladenine, 1% arabinosylcytosine, 1% 5-chloro-arabinosylcytosine, 5% arabinosylhypoxanthine 5-monophosphate and 5% viramidine.

Conclusions:

Of the compounds tested, topically applied cidofovir was the most effective treatment of cutaneous vaccinia virus infections in immunosuppressed mice. Topical treatment with cidofovir could be considered as an adjunct to intravenous drug therapy for serious infections.
Postponing retirement age and labor force participation: the role of family transfers
Authors: Belan Pascal , Messe Pierre-Jean , Wolff François-Charles
Published: February 2011

Résumé Dans cet article, nous examinons les conséquences du recul de l’âge de départ en retraite dans un modèle à générations imbriquées avec production domestique et transferts intrafamiliaux sous la forme de temps de garde des petits-enfants. Nous montrons qu’une modification de l’âge de départ en retraite modifie le taux d’emploi des seniors, mais aussi celui des jeunes en raison d’interactions avec les transferts familiaux. Dans certains cas, un départ en retraite plus tardif peut accroître le temps que les grands-parents consacrent à leurs petits-enfants, ce qui augmente l’offre de travail des jeunes parents. Nous étudions alors les conditions sous lesquelles cette externalité familiale positive est valide. Enfin, nous analysons numériquement les conséquences du recul de l’âge de départ en retraite sur l’offre de travail des jeunes et des seniors selon la paramétrisation des fonctions de production domestique. Classification JEL : J26.
Partenariats public-privé et investissements de fin de contrat : le cas de l'industrie de l'eau en France
Authors: Chong Eshien , Huet Freddy
Published: February 2011

Résumé L’efficacité des partenariats public-privé (PPP) dans les industries de service public en réseau a été remise en cause par de nombreux auteurs. Une des défaillances majeure reprochée à ce type d’accords concerne le manque d’incitation de l’opérateur en place à investir en fin de contrat. Le but de cet article est double. Tout d’abord, nous expliquons pourquoi l’industrie française de l’eau se caractérise par une logique de sous-investissement en fin de contrat. Ensuite, en utilisant une base de données collectée sur un échantillon de 5000 communes françaises en 2001, nous proposons une série de tests économétriques qui montre que dans l’industrie de l’eau, les opérateurs privés sont de moins en moins incités à investir lorsque l’échéance du contrat se rapproche. Plus précisément, nous montrons qu’une solution adoptée par les communes pour faire face à ce problème est de se substituer aux firmes privées pour les investissements spécifiques de fin de contrat. Nos résultats confirment ainsi la proposition généralement admise par la théorie des contrats de risque de sous-investissement des opérateurs privés en fin de partenariat public-privé. Classification JEL : D23, L51, L95.
Estratigrafía, evolución estructural y restauración. El caso de la iglesia de Santa Eulalia en Marquínez (Álava)
Authors: Cámara Leandro
Published: February 2011

Se presenta un caso de evaluación de la estabilidad de una iglesia abovedada que toma el análisis arqueológico como principal referencia de contraste de los resultados del estudio estructural. La consideración de los edificios históricos como entidades temporales en las que se combinan la acción degradante de la naturaleza y la conservadora del hombre confiere al análisis de su seguridad estructural una mejor perspectiva que la presupuesta en los más convencionales análisis basados exclusivamente en las teorías estructurales generales y demuestra que un mejor conocimiento del comportamiento de la estructura a lo largo del tiempo debe conducir a un mayor respeto de su integridad material y a un abierto rechazo de las restauraciones más intervencionistas justificadas sólo por esos estudios estructurales. Se hace una breve revisión de la teoría de estados límite y su aplicación a las estructuras de fábrica y a la iglesia de Santa Eulalia de Marquínez en particular; en paralelo se presenta el resultado del estudio histórico de su evolución constructiva; y se conjugan las conclusiones de ambos análisis en una secuencia temporal de la evolución estructural, una revisión de su seguridad y una propuesta de intervención
La iglesia altomedieval de la Asunción en San Vicente del Valle (Burgos): historiografía, estratigrafía e interpretación
Authors: Arce Sainz Fernando
Published: February 2011

Se presentan los resultados de la lectura estratigráfica de la iglesia de la Asunción (San Vicente del Valle, Burgos), en la que se descubren dos intervenciones arquitectónicas relevantes prerrománicas (la construcción de un primer edificio y su transformación en un momento posterior). El edifico es interpretado como parte de una familia arquitectónica coherente, técnica e históricamente, cuyos diferentes miembros pueden y deben compartir información entre ellos en aras de una comprensión sistémica de la producción arquitectónica que ayude a avanzar en el actual contexto historiográfico, dominado por una discusión constante sobre las cronologías de estos edificios.
Arqueologia do edificado em contexto de Arqueologia preventiva: o exemplo da Baixinha de Coimbra (Portugal)
Authors: Basílio Lília , Almeida Miguel
Published: February 2011

[pt] Em Portugal a inclusão de estudos detalhados dos edifícios a demolir no contexto de intervenções de Arqueologia preventiva / de salvamento permanece rara, reservando-se a leitura e interpretação dos conjuntos edificados quase exclusivamente para projectos específicos da área da Conservação e restauro, maioritariamente de edifícios com carácter monumental. Esta situação tem provocado perdas irrecuperáveis de informação fundamental para a história das cidades portuguesas. Uma intervenção de Arqueologia preventiva, prévia à execução de um projecto de construção com impacto significativo sobre a malha urbana actual da Baixinha de Coimbra ,constituiu uma oportunidade singular para o desenvolvimento de um projecto global de Arqueologia que articula a análise do edificado com trabalhos de escavação arqueológica. O projecto da Baixinha de Coimbra (actualmente em curso, mesmo no que respeita aos trabalhos de aquisição de dados no terreno) demonstra: (1) a relevância e o potencial informativo dos edifícios de arquitectura civil, quando encarados como objectos estratificados cuja compreensão surge indispensável para a reconstituição da história dos centros urbanos; e (2) o papel fundamental a desempenhar pela Arqueologia preventiva neste processo fundamental de construção de conhecimento sobre a história das cidades.
Neste sentido, insistimos sobre a necessidade urgente de constituição de colecções de referência de materiais e técnicas construtivas geográfica e cronologicamente contextualizadas e da imposição do princípio de «conhecer para intervir», elevando o conhecimento objectivo da história dos edifícios e da sua envolvente urbana à categoria de eixo fundamental das opções estratégicas dos programas de intervenção urbana, maxime no caso de centros históricos.