Comparison of Mycoplasma hyopneumoniae and porcine circovirus 2 commercial vaccines efficacy when applied separate or combined under experimental conditions.

BACKGROUND: Mycoplasma hyopneumoniae (Mhyo) and Porcine circovirus 2 (PCV-2) are two of the most significant infectious agents causing economic losses in the weaning to slaughter period. Due to their similar vaccination age, the objective of this study was to assess the efficacy of two already existing Mhyo (Hyogen®) and PCV-2 (Circovac®) vaccines when administered separately or combined (RTM) by means of Mhyo or PCV-2 experimental challenges. RESULTS: Seven groups of animals were included in the study, being three of them challenged with PCV-2, three with Mhyo and one composed of non-challenged, non-vaccinated pigs. Within each experimental challenge, non-vaccinated (NV) groups were compared with double vaccinated groups using the commercial products separated (VS) or combined (VC). Both vaccinated groups showed significant differences for most parameters measured regarding PCV-2 (serology, percentage of infected animals and viral load in tissues) and Mhyo (serology and gross lesions) when compared to NV groups. VS and VC offered similar results, being only significantly different the PCV-2 antibody values at different time points (higher in the VS group) of the study, although not at the termination day (21 days post-PCV-2 inoculation). CONCLUSION: The present study expands the knowledge on the possibility of using two separate Mhyo and PCV-2 commercial vaccines as a RTM product, which offered equivalent virological, immunological and pathological outcomes as compared to these vaccines when used by separate.

Microphysical explanation of the RH-dependent water affinity of biogenic organic aerosol and its importance for climate.

A large fraction of atmospheric organic aerosol (OA) originates from natural emissions that are oxidized in the atmosphere to form secondary organic aerosol (SOA). Isoprene (IP) and monoterpenes (MT) are the most important precursors of SOA originating from forests. The climate impacts from OA are currently estimated through parameterizations of water uptake that drastically simplify the complexity of OA. We combine laboratory experiments, thermodynamic modeling, field observations, and climate modeling to (1) explain the molecular mechanisms behind RH-dependent SOA water-uptake with solubility and phase separation; (2) show that laboratory data on IP- and MT-SOA hygroscopicity are representative of ambient data with corresponding OA source profiles; and (3) demonstrate the sensitivity of the modeled aerosol climate effect to assumed OA water affinity. We conclude that the commonly used single-parameter hygroscopicity framework can introduce significant error when quantifying the climate effects of organic aerosol. The results highlight the need for better constraints on the overall global OA mass loadings and its molecular composition, including currently underexplored anthropogenic and marine OA sources.

Arctic sea ice melt leads to atmospheric new particle formation.

Atmospheric new particle formation (NPF) and growth significantly influences climate by supplying new seeds for cloud condensation and brightness. Currently, there is a lack of understanding of whether and how marine biota emissions affect aerosol-cloud-climate interactions in the Arctic. Here, the aerosol population was categorised via cluster analysis of aerosol size distributions taken at Mt Zeppelin (Svalbard) during a 11 year record. The daily temporal occurrence of NPF events likely caused by nucleation in the polar marine boundary layer was quantified annually as 18%, with a peak of 51% during summer months. Air mass trajectory analysis and atmospheric nitrogen and sulphur tracers link these frequent nucleation events to biogenic precursors released by open water and melting sea ice regions. The occurrence of such events across a full decade was anti-correlated with sea ice extent. New particles originating from open water and open pack ice increased the cloud condensation nuclei concentration background by at least ca. 20%, supporting a marine biosphere-climate link through sea ice melt and low altitude clouds that may have contributed to accelerate Arctic warming. Our results prompt a better representation of biogenic aerosol sources in Arctic climate models.

Primary and secondary organics in the tropical Amazonian rainforest aerosols: chiral analysis of 2-methyltetraols.

This work presents the application of a new method to facilitate the distinction between biologically produced (primary) and atmospherically produced (secondary) organic compounds in ambient aerosols based on their chirality. The compounds chosen for this analysis were the stereomers of 2-methyltetraols, (2R,3S)- and (2S,3R)-methylerythritol, (l- and d-form, respectively), and (2S,3S)- and (2R,3R)-methylthreitol (l- and d-form), shown previously to display some enantiomeric excesses in atmospheric aerosols, thus to have at least a partial biological origin. In this work PM10 aerosol fractions were collected in a remote tropical rainforest environment near Manaus, Brazil, between June 2008 and June 2009 and analysed. Both 2-methylerythritol and 2-methylthreitol displayed a net excess of one enantiomer (either the l- or the d-form) in 60 to 72% of these samples. These net enantiomeric excesses corresponded to compounds entirely biological but accounted for only about 5% of the total 2-methyltetrol mass in all the samples. Further analysis showed that, in addition, a large mass of the racemic fractions (equal mixtures of d- and l-forms) was also biological. Estimating the contribution of secondary reactions from the isomeric ratios measured in the samples (=ratios 2-methylthreitol over 2-methylerythritol), the mass fraction of secondary methyltetrols in these samples was estimated to a maximum of 31% and their primary fraction to a minimum of 69%. Such large primary fractions could have been expected in PM10 aerosols, largely influenced by biological emissions, and would now need to be investigated in finer aerosols. This work demonstrates the effectiveness of chiral and isomeric analyses as the first direct tool to assess the primary and secondary fractions of organic aerosols.

Patterns of deletions and the distribution of breakpoints in the dystrophin gene in Czech patients with Duchenne and Becker muscular dystrophy (statistical comparison with results from several other countries).

Deletion pattern analysis of the dystrophin gene was performed in 115 unrelated Czech patients with Duchenne and Becker muscular dystrophy. In 50 patients (43.5% of the analysed patients) exon deletions were detected by routinely performed multiplex PCR for 18 selected exons and for the area of musclespecific promoter of the dystrophin gene. All startpoints and endpoints of deletions (100 breakpoints) were detected using PCRs for another 29 exon areas of the dystrophin gene (altogether primers for 47 different exons were used). Most of the breakpoints were found in introns 44 (16% of breakpoints), 47 (14%) and 50 (8%). The comparison of distributions of breakpoints in the area of the main hot spot of the dystrophin gene (introns 43-52) was made (chi 2 test in a contingency table) in six different populations from the Czech Republic, Bulgaria, Hungary, Italy, Turkey and India. In compared populations, statistically significant differences were found by the pooled test. No significant difference between the Czech population and other studied populations was found by pair comparisons. On the other hand, pair comparisons revealed significant differences between populations from Bulgaria and Hungary, Bulgaria and Turkey, Hungary and Italy. The results of the presented study support the theory suggested by other authors that specific differences in intron sequences of the dystrophin gene can exist between different populations, possibly as a result of a genetic drift.

2D and 3D finite element pre- and post-processing in orthopaedy.

The present widespread tomographic techniques based on computed tomography (CT), magnetic resonance imaging (MRI) and automatic 2D and 3D reconstructions also involve numerous new points of view for planning surgical techniques in orthopaedy. These require efficient pre- and post-processing methods. By pre-processing and post-processing is meant both the generation of a finite element mesh that numerically models human joints and the visualization of the results obtained as required by the surgeon. Since the numerical reconstructions of human joints are based on the finite element approximation of contact problems assuming linear elasticity, the main goal of pre-processing is to generate triangular (2D) and tetrahedral (3D) meshes of objects with a 'reasonable' boundary-human joints. In our paper we restrict ourselves, for the sake of simplicity, to polygonal (resp. polyhedral) objects. The idea of preprocessing is based on the modified method of Delaunay Mangulalia and on the so-called relaxation technique. After the generation of the finite element mesh and after numerical simulation of surgical problems of orthopaedy, the results obtained as stress-strain fields, temperature, etc. may be visualized in a graphical form on the computer screen as well as on other media.

Induction and characterization of monoclonal anti-idiotypic antibodies to tick-borne encephalitis virus neutralizing antibody.

Seven monoclonal anti-idiotypic antibodies (anti-ID MAbs, Ab2) were generated against virus-neutralizing and hemagglutination-inhibiting monoclonal antibody (Ab1) specific for tick-borne encephalitis (TBE) virus. Six of these anti-ID MAbs inhibited the binding of Ab1 to the virus antigen, thus classifying these anti-ID antibodies as Ab2 beta or AB2 gamma. Inhibition tests with heterologous anti-TBE sera revealed that these anti-ID MAbs were not recognized by anti-TBE antibodies and therefore they do not carry an internal image of TBE virus antigen. Hence, the anti-ID MAbs may be classified as Ab2 gamma type. None of the anti-ID MAbs induced production of antiviral antibodies nor protective immunity in syngeneic Balb/c mice. Using these anti-ID MAbs four nonoverlapping idiotopes were identified on Ab1 variable region.

Psychological and behavioral differences among females classified as bulimic, obligatory exerciser and normal control.

The compulsion to maintain a lean body shape while living in a society obsessed with food may encourage the use of dieting, binge eating and purging behaviors in young women. The body of literature on bulimia nervosa (Boskind-Lodahl and Sirlin 1977; Fairburn and Cooper 1984; Katzman and Wolchik 1984; Scott 1988) clearly establishes its relationship to the current American fashion for thinness and the value placed on physical attractiveness for self-esteem. This notion promotes a multitude of weight control strategies ranging from self-starvation (Humphrey 1983; Brownell and Foreyth 1986) to cigarette smoking (Klesges and Klesges 1988), many of which may have a profound influence on maintenance of good health. Similar to weight control, exercise behavior could be viewed as falling on a continuum from reasonable efforts to maintain physical fitness to a preoccupation with exercise that is far out of proportion to the expected benefits of a 30-minute, three to five day a week routine. Characteristics of obligatory exercise have been described by several researchers and include maintaining a rigid schedule of intense exercise; resisting temptation to lapse into nonexercising; feelings of guilt and anxiety when the exercise schedule is violated; compensatory increase in exercise to make up for lapses; pushing oneself even when tired, ill, or injured; mental preoccupation with exercise; and detailed recordkeeping on exercise (Yates et al. 1983; Blumenthal et al. 1984; Nudelman et al. 1988). In a competitive society, obsessive exercise behaviors may be linked to the development of rigid dietary guidelines while one strives toward the "optimal" lean-fat ratio of body composition.(ABSTRACT TRUNCATED AT 250 WORDS)

Genetic Mapping in the Lignin-Degrading Basidiomycete Phanerochaete chrysosporium.

A method of meiotic segregation analysis based on recombinant selection in the homothallic basidiomycete Phanerochaete chrysosporium was developed. Using this method, we were able to reveal linkage relationships and to estimate recombination frequencies between seven mutations to auxotrophy. We detected two linkage groups, the first containing four and the second three of the seven mapped mutations.

Fiber optic probe augmented sonic scaling versus conventional sonic scaling.

Several factors, including access and visualization problems, make total deposit removal during scaling and root planing procedures extremely difficult. This study examined the effectiveness of a mode of therapy designed to improve access and visualization for sonic scaling compared to closed sonic instrumentation. Teeth with moderate to deep probing depths in six patients scheduled to receive immediate dentures were divided into three experimental groups: Group I, sonic scaling with access augmented by interdental papilla reflection and fiber optic illumination/transillumination (34 surfaces); Group II, closed sonic scaling (34 surfaces); and Group III, untreated controls (35 surfaces). Immediately after treatment the experimental teeth were extracted, stained with toluidine blue, and interproximal areas evaluated for remaining accretions with a microscope-digitizing pad-computer system. Group I had a significantly lower percentage (P less than 0.01) of remaining subgingival accretion coverage than Group II (1.30 +/- 0.25% vs 6.35 +/- 1.08%), and both Group I and II demonstrated significantly (P less than 0.01) fewer deposits than the control surfaces (46.61 +/- 4.32%). These findings suggest that minimal tissue reflection and fiber optic illumination/transillumination are beneficial adjuncts to deposit removal in moderate to deep periodontal pockets.

Self-sterilization of the electrosurgery electrode.

Sterilization of the electrode used in electrosurgery has been assumed to occur at the instant of contact of the energized electrode tip to a grounded source. This study evaluated whether the time of electrode activation or the amount of energy delivered is important in the self-sterilization process. Standard bacteriologic culturing techniques were employed to assess sterility of the electrode tip following activation. Total time of application of the current and the energy used were recorded on audiotape and later tabulated. The data indicate that the time of energizing and the energy units used are critical in the sterilization of the electrode tip. These results confirm that self-sterilization of the electrosurgery electrode tip occurs, but full confidence is not realized with the time intervals commonly employed in clinical practice. The electrode tip must be considered a potential source of bacterial contamination of electrosurgically managed dental procedures.

Electrosurgery--a biological approach.

Electrosurgery has been used in dentistry for more than 50 years. Both opponents and advocates of electrosurgery have presented a variety of clinical studies in favour of their respective opinions, which are discussed in the following review. In some studies, wounds created by electrosurgical techniques were observed through the healing stages, in comparison to those following incision by a surgical blade, with no significant difference being discovered. Other studies reported that the histologic response of oral connective tissue to electrosurgery was adverse in some animal and human models. However, neither of these groups used methods that allowed documentation or control of operating variables. A critical evaluation of controlled clinical studies shows that adverse responses of (connective) tissue, epithelium, bone, cementum, and periodontal attachment are related to an excessive lateral heat production during the procedure. With electrosurgery, the clinician can control the inherent variables. Waveform, frequency, size of the electrode, time of contact and cooling periods are some of those considered to be of importance in the studies. On the basis of the research reports, clinical guidelines have been developed to give practical advice to the clinician using electrosurgery. Providing that these safeguards are adhered to, scientific evidence supports the biological compatibility of electrosurgery for intraoral surgical procedures.

Histologic evaluation of gingival response to an electrosurgical blade.

Lateral heat production during the use of electrosurgical procedures in the oral cavity causes denaturation of the connective tissue adjacent to the incision line. This study evaluated the denatured zone following electrosurgery incision in dog gingiva with a traditional tungston wire electrode and a no. 15 surgical blade adapted for electrosurgery use. The effects of using a passive electrode during surgical procedures and using an "autosensor" circuit to control power adjustment were also evaluated. It was found that a surgical blade adapted for electrosurgery produces a zone of denatured tissue that is not statistically different from that produced with a wire electrode. Moreover, no differences were noted between incisions produced with manual power adjustment and those with power controlled by the "autosensor" circuit. A significantly wider zone of denatured tissue was produced when incisions were made without a passive electrode in place.

Genetic recombination in auxotrophic strains of Phanerochaete chrysosporium.

Four auxotrophic strains of the ligninolytio basidiomycetePhanerochaete chrysosporium were obtained by UV mutagenesis. The heterokaryotic mycelium formed by complementation of different auxotrophic isolates was able to fruit and produce basidiospores. From the hasidiospore progeny of the heterokaryons prototrophic strains and strains with a recombined set of parental nutritional requirements were isolated. Genetic recombination hence takes place in fruit bodies produced by the heterokaryotic mycelium.

Determination of plasma catecholamines in dogs after experimental gingival retraction with epinephrine-impregnated cord.

Blood catecholamine levels were determined by high-performance liquid chromatography after placement of the cord around two teeth in a random sequence of the following treatments: (1) untreated cord to intact gingival crevice (C), (2) epinephrine cord to intact crevice (E1), and (3) epinephrine cord to a crevice disrupted with a tapered diamond bur to simulate a subgingival procedure such as in crown preparation (E2). Each cord was left in place for 30 min while blood was drawn from the external jugular vein at 0, 5, 10, 20 and 30 min, and at 10 and 30 min after removal of the cord. Catecholamine values were compared to baseline (time 0) measurements. Treatment C resulted in no significant change in blood catecholamines. Treatment E1 caused a significant increase (p less than 0.01) in blood epinephrine levels, reaching a 641 per cent increase at 30 min. Treatment E2 produced a highly significant increase (p less than 0.001) in blood epinephrine with a greater than 5000 per cent increase 10 min after cord removal. Norepinephrine and dopamine levels were not significantly altered by any of the treatments.