B-mode and M-mode echocardiography of endurance horses raised in São Paulo State, Brazil

This study aimed to evaluate cardiac dimensions and indexes of cardiac function in endurance horses using bidimensional- (B-) mode and guided unidimensional- (M-) mode echocardiography. Thirty-five Arabian and crossbred Arabian male and female horses, aged 5 to 18 years old, with an average weight of 415.51 ± 36.76 kg and at least 1 year of endurance training and competition experience, were used. The following values were obtained for B-mode echocardiography in the right parasternal window (see “Materials and Methods” for expanded terms): RVIDd 2.54 ± 0.56 cm; RVIDs 2.08 ± 0.68 cm; IVSd 2.60 ± 0.31 cm; IVSs 3.90 ± 0.44 cm; LVIDd 10.07 ± 0.85 cm; LVIDs 6.65 ± 0.92 cm; LVFWd 2.50 ± 0.30 cm; LVFWs 3.74 ± 0.35 cm; Aod 7.86 ± 0.72 cm; LAs 10.84 ± 0.93 cm; Vd 578.40 ± 108 cm³; Vs 232.68 ± 70.61 cm³; FS% 34.99% ± 8.02%; EF% 60.13% ± 8.29%; E-point 2.25 ± 0.49 cm; and LAs:Aod 1.38 ± 0.16 cm. Using guided M-mode, the following values were obtained: RVIDd 2.04 ± 0.55 cm; RVIDs 1.61 ± 0.71 cm; IVSd 2.68 ± 0.29 cm; IVSs 4.17 ± 0.42 cm; LVIDd 9.72 ± 0.72 cm; LVIDs 5.94 ± 0.96 cm; LVFWd 2.69 ± 0.32 cm; LVFWs 4.23 ± 0.69 cm; Aod 7.21 ± 0.75 cm; Vd 534.24 ± 87.53 cm³; Vs 181.75 ± 67.69 cm³; FS% 39.06% ± 7.66%; EF% 66.38% ± 9.41%; and E-point 1.96 ± 0.58 cm.

Introduction

In equine sports medicine, it is important to evaluate the cardiovascular condition of the athlete. More recently, echocardiography has been used for this purpose.Echocardiography is an invaluable diagnostic aid, since it is non-invasive and easy to perform,[1, 2 and 3] while offering a dynamic and functional evaluation of the heart. [2, 3, 4 and 5].Initially, studies on the M-mode were made, including measurements of normal cardiac dimensions in horses[6 and 7] and foals and for the diagnosis of several cardiac diseases. [1] With the introduction of the B-mode technique in the mid-1980s and its validation, a more detailed anatomic evaluation was possible, [2, 8 and 9] thus allowing the observation of cardiac abnormalities. [10]Though echocardiographic examination could be used to predict the athletic condition of individuals,[11] this is possible only if normal echocardiographic reference values are established. As different breeds have different biotypes and develop different aptitudes, it is necessary to provide enough information for each type of work or breed. Research includes data for the Thoroughbred racehorse [3, 12 and 13] and Standardbred trotter, [14 and 15] which perform essentially anaerobic work.The endurance race is a modality that is growing significantly in Brazil, both in number of participants and in quality and training of the animals. The endurance horse demands a physical conditioning that differs from that required for racehorses, especially owing to the development of aerobic work. In addition, the animals are mainly Arabian or Arabian crossbred, which have a particular biotype. Because of these facts, and the lack of data about the echocardiographic behavior of endurance horses, this study aimed to determine the dimensions and indexes of cardiac function for horses with endurance training using B-mode and guided M-mode echocardiography.

Materials and methods

Thirty-five clinically normal endurance Arabian and Arabian crossbred male and female horses between 5 and 18 years old, with an average weight of 415.51 ± 36.76 kg, were included in the study. All animals had at least 1 year of training and experience in competitions and were kept under similar hygienic, sanitary, and nutritional management. Training consisted of trail rides, alternating walking, trotting, and galloping, from 20 to 40 km per day, 3 to 4 times per week.The echocardiographic examination was performed with a Sonosite model 180 Plus v. 1.9 echocardiograph, using a 2-4–MHz electronic microconvex transducer with a maximal depth of 24 cm.The animals were prepared as previously reported,[4, 16 and 17] the hair being coated with large amounts of acoustic coupling gel. During the examination, the animals were at rest, calm, and physically restrained only by the halter, in a quiet and dark room.The following echocardiographic measurements, in B-mode as well as guided M-mode, were performed: the left atrium internal diameter in systole (LAs), only in B-mode, in the long axis view, dorsal to the annulus[15]; the right ventricle internal diameter, in diastole (RVIDd) and in systole (RVIDs); the interventricular septum thickness, in diastole (IVSd) and in systole (IVSs); the left ventricle internal diameter, in diastole (LVIDd) and in systole (LVIDs); and the left ventricle free wall thickness, in diastole (LVFWd) and in systole (LVFWs), from the left ventricle short axis view at the chordal level; and the aortic root internal diameter (Aod), from the aortic valve short axis view. The B-mode measurements were taken according to Patteson et al, [12] and the M-mode measurements were based on Long et al. [18]Images were obtained from the right hemithorax. The position used for the transducer to obtain the standardized images for B-mode and guided M-mode were determined and used as described in Reef.[4 and 17]The echocardiographic examination began using the B-mode echocardiography, with the establishment of the tomographic planes, evaluating morphology of the cardiac structures and their movement in a global manner.The first image obtained was the right parasternal long axis view, with the observation of the ventricle inlets, atrioventricular valves, and both atria. With the transducer positioned to optimize visualization of the left atrium, usually with a minimal dorsal angulation, the LAs measurement was made, immediately before the opening of the mitral valve (Fig 1).     

Botulinum toxin A as a treatment for delayed gastric emptying in a dog

A toy Australian shepherd dog was referred for bile peritonitis following excision of a biliary mucocele. Subsequent delayed gastric emptying was refractory to prokinetic therapy but responded to injection of botulinum toxin A into the muscularis layer of the pylorus; a novel therapy for delayed gastric emptying in dogs.     

Reactivation of ocular dominance plasticity in the adult visual cortex

In young animals, monocular deprivation leads to an ocular dominance shift, whereas in adults after the critical period there is no such shift. Chondroitin sulphate proteoglycans (CSPGs) are components of the extracellular matrix (ECM) inhibitory for axonal sprouting. We tested whether the developmental maturation of the ECM is inhibitory for experience-dependent plasticity in the visual cortex. The organization of CSPGs into perineuronal nets coincided with the end of the critical period and was delayed by dark rearing. After CSPG degradation with chondroitinase-ABC in adult rats, monocular deprivation caused an ocular dominance shift toward the nondeprived eye. The mature ECM is thus inhibitory for experience-dependent plasticity, and degradation of CSPGs reactivates cortical plasticity.     

The neural basis of loss aversion in decision-making under risk

People typically exhibit greater sensitivity to losses than to equivalent gains when making decisions. We investigated neural correlates of loss aversion while individuals decided whether to accept or reject gambles that offered a 50/50 chance of gaining or losing money. A broad set of areas (including midbrain dopaminergic regions and their targets) showed increasing activity as potential gains increased. Potential losses were represented by decreasing activity in several of these same gain-sensitive areas. Finally, individual differences in behavioral loss aversion were predicted by a measure of neural loss aversion in several regions, including the ventral striatum and prefrontal cortex.     

Molecular and physiological characterisation of psychrotrophic hydrocarbon-degrading bacteria isolated from Terra Nova Bay (Antarctica)

A set of 21 Antarctic marine bacteria isolated from the Ross Sea and able to utilise diesel fuel as the sole carbon and energy source was characterised. Isolates were analysed by amplified 16S rDNA restriction analysis using the enzyme AluI, resulting in two different groups corresponding to different bacterial species. These species were assigned to the genera Rhodococcus and Alcaligenes, on the basis of 16S rDNA sequencing. This low degree of inter-specific biodiversity was parallel to a low intra-specific biodiversity, as shown by Random Amplified Polymorphic DNA analysis. Then, a 550-bp DNA fragment coding for the inner region of alkane mono-oxygenase was PCR-amplified from the genome of each strain. The phylogenetic analysis of the sequence of the putative AlkB protein coded for by the amplified DNA fragment revealed that these alkB genes were very likely inherited by horizontal gene transfer. Lastly, the analysis of the biodegradation ability of four strains revealed two different strategies of hydrocarbon uptake, mediated either by bio-surfactants and peculiar of Rhodococcus isolates, or by membrane modifications and shown by Alcaligenes isolates. In order to understand the interrelationships between hydrocarbon-degrading isolates, the dynamics of two strains, belonging to Rhodococcus and Alcaligenes, grown together in a co-culture was also followed over a seventeen days period.     

Anti-inflammatory, antioxidant and antifungal furanosesquiterpenoids isolated from Commiphora erythraea (Ehrenb.) Engl. resin

The topical anti-inflammatory, free radical scavenging and antifungal activities of essential oils and extracts of Commiphora erythraea (Ehrenb.) Engl. resin were investigated. The hexane extract significantly inhibited oedema when applied topically in Croton oil-induced ear oedema assay in mice. The same extract showed antioxidant activity in DPPH radical scavenging assay. A bioguided separation of the hexane extract led to the isolation of furanosesquiterpenoids 1 and 2 that showed a weak antifungal activity, while compounds 3-5 resulted to be antioxidant (EC₅₀ 4.28, 2.56 and 1.08 mg/mL, respectively) and anti-inflammatory (30, 26 and 32% oedema reduction, respectively).     

Copper complexes grafted to functionalized silica gel as wood preservatives against the brown rot fungus <Emphasis Type="Italic">Coniophora puteana</Emphasis>

Wood modification with siloxanes bearing amino groups with copper-linking function was carried out by a sol–gel process. Tetraethoxysilane (TEOS) and 3-aminopropyltriethoxysilane (APTES) were the main components. Two different procedures were followed: a two-step process (impregnation with the TEOS/APTES mixture followed by dipping into a copper sulphate solution) and a one-step process (impregnation with a homogeneous sol mixture of TEOS, APTES and copper (II) chloride). The obtained materials were characterized by infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) and energy dispersive X-ray microanalysis. The determination of copper content before and after leaching was performed by atomic absorption spectroscopy. The efficacy against the brown rot fungus Coniophora puteana was tested by an accelerated procedure. SEM analyses showed that silicon penetrated into wood, while copper is effectively drawn into wood only in the one-step treatment. Copper fixation to the silica gel proved to be adequately strong. Both sol–gel treatments gave good protection against Coniophora puteana.     

Testing Scandium Method to Quantify Suspended Particles Adhesion to the External Surface of Periphyton Communities

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