Effect of autologous adipose tissue-derived mesenchymal stem cells on neovascularization of artificial equine tendon lesions

AIMS

To investigate whether autologous adipose tissue-derived mesenchymal stem cells (AT-MSCs) treatment of tendon lesions increases neovascularization during tendon healing.

MATERIALS & METHODS

A standardized surgical model was used to create lesions in both front limb superficial digital flexor tendons (SDFTs) of nine horses. Either AT-MSCs or control substance was injected intralesionally 2 weeks post-surgery. Color Doppler ultrasonography of SDFTs was performed at regular intervals. Horses were euthanized 22 weeks post-treatment and SDFTs were harvested for histology.

RESULTS

The color Doppler ultrasonography signal was significantly more extensive at 2 weeks post-treatment and the number of vessels counted on histologic slides was significantly higher at 22 weeks post-treatment in AT-MSC-treated SDFTs.

CONCLUSION

Our findings indicate that AT-MSC treatment has a beneficial effect on neovascularization of healing tendons.

The Early Mediaeval manorial estate of Gars/Thunau, Lower Austria: An enclave of endemic tuberculosis?

In recent decades, an increasing number of studies have aimed to shed light on the origin and spread of tuberculosis in past human populations. Here we present the results of a systematic palaeodemographic and palaeopathological survey of the Early Mediaeval population of Gars/Thunau (Lower Austria), which - at this stage - includes 373 individuals recovered at two archaeological sub-sites: a fortified settlement (including a necropolis) at the top of a hill - probably reserved for social and military elites; and a large riverine settlement at the foot of the hill, a so-called 'suburbium', where burials and an area of 'industrial' character were discovered. We recorded a great number of pathological alterations and a variety of 'classical' features of tuberculosis, such as vertebral destructions (Pott's disease) and joint destructions, and other pathological (unspecific) features probably linked with Mycobacterium tuberculosis infection (e.g. new bone formation at the inner surface of the ribs, endocranial alterations in the form of 'pits', and new bone formation at the cranial base). We hypothesize that the two contemporaneous (∼900-1000 AD) populations of Gars/Thunau differed not only in their social affiliation/condition, but also in the type and frequencies of their population-density-related infectious diseases (in particular tuberculosis). Moreover, we investigated the molecular genetic evidence of the causative organism in a few selected immatures exhibiting pathological changes at the inner wall of the cranium and discuss these findings in regard to the macroscopic features observed. Finally, we analysed carbon and nitrogen stable isotopes of both populations and strontium isotope ratios of the hill-top inhabitants in order to reconstruct certain aspects of diet and mobility to test our hypothesis concerning the specific social and/or military character of the site.

Ground-state cooling of a carbon nanomechanical resonator by spin-polarized current

We study the nonequilibrium steady state of a mechanical resonator in the quantum regime realized by a suspended carbon nanotube quantum dot in contact with two ferromagnets. Because of the spin-orbit interaction and/or an external magnetic field gradient, the spin on the dot couples directly to the flexural eigenmodes. Accordingly, the nanomechanical motion induces inelastic spin flips of the tunneling electrons. A spin-polarized current at finite bias voltage causes either heating or active cooling of the mechanical modes. We show that maximal cooling is achieved at resonant transport when the energy splitting between two dot levels of opposite spin equals the vibrational frequency. Even for weak electron-resonator coupling and moderate polarizations we can achieve ground-state cooling with a temperature of the leads, for instance, of T = 10 ω.

A sensitive and robust method for automated on-line monitoring of enzymatic activities in water and water resources

The realisation of a novel concept for automated on-line monitoring of enzymatic activities in water was successfully demonstrated by long-term field testing at two remote Austrian ground water resources. The β-D-glucuronidase (GLUC) activity was selected as a representative enzymatic model parameter for the on-line determination. But the device can be adapted for any enzymatic reaction with diagnostic relevance for microbial water quality monitoring, as demonstrated for the β-D-galactosidase activity. Automated filtration of volumes up to 5 litres supports sensitive quantification of enzymatic activities. Internet-based data transfer, using internal control parameters for verification and a dynamic determination of the limit of quantification, enabled robust enzymatic on-line monitoring during a 2-year period. A proportion of 5,313 out of 5,506 GLUC activity measurements (96.5%) could be positively verified. Hydrological (discharge, gauge, turbidity, temperature, pH, electric conductivity, spectral absorbance coefficient at 254 nm) as well as microbiological parameters (Escherichia coli, coliforms) were concurrently determined to characterise the investigated ground water resources. The enzymatic on-line measurements closely reflected the different hydrological conditions and contamination patterns of the test sites. Contrary to expectations, GLUC did not qualify as a proxy-parameter for the occurrence of cultivation-based E. coli contamination and warrants further detailed investigations on its indication capacity as a rapid means for microbial faecal pollution detection in such aquatic habitats. Microbial on-line monitoring is likely to become more important in the future, complementing existing surveillance strategies for water safety management. Further perspectives on the application of such analytical on-line technologies, such as their connection with event-triggered sampling and standardised diagnostics, are discussed.

Functional ecology of the ciliate Glaucomides bromelicola, and comparison with the sympatric species Bromeliothrix metopoides

We investigated the ecology and life strategy of Glaucomides bromelicola (family Bromeliophryidae), a very common ciliate in the reservoirs (tanks) of bromeliads, assessing its response to food quality and quantity and pH. Further, we conducted competition experiments with the frequently coexisting species Bromeliothrix metopoides (family Colpodidae). In contrast to B. metopoides and many other colpodean ciliates, G. bromelicola does not form resting cysts, which jeopardizes this ciliate when its small aquatic habitats dry out. Both species form bactivorous microstomes and flagellate-feeding macrostomes. However, only G. bromelicola has a low feeding threshold and is able to adapt to different protist food. The higher affinity to the local bacterial and flagellate food renders it the superior competitor relative to B. metopoides. Continuous encystment and excystment of the latter may enable stable coexistence of both species in their natural habitat. Both are tolerant to a wide range of pH (4–9). These ciliates appear to be limited to tank bromeliads because they either lack resting cysts and vectors for long distance dispersal (G. bromelicola) and/or have highly specific food requirements (primarily B. metopoides).

Systematics and species-specific response to pH of Oxytricha acidotolerans sp. nov. and Urosomoida sp. (Ciliophora, Hypotricha) from acid mining lakes

We investigated the morphology, phylogeny of the 18S rDNA, and pH response of Oxytricha acidotolerans sp. nov. and Urosomoida sp. (Ciliophora, Hypotricha) isolated from two chemically similar acid mining lakes (pH~2.6) located at Langau, Austria, and in Lusatia, Germany. Oxytricha acidotolerans sp. nov. from Langau has 18 frontal-ventral-transverse cirri but a very indistinct kinety 3 fragmentation so that the assignment to Oxytricha is uncertain. The somewhat smaller species from Lusatia has a highly variable cirral pattern and the dorsal kineties arranged in the Urosomoida pattern and is, therefore, preliminary designated as Urosomoida sp. The pH response was measured as ciliate growth rates in laboratory experiments at pH ranging from 2.5 to 7.0. Our hypothesis was that the shape of the pH reaction norm would not differ between these closely related (3% difference in their SSU rDNA) species. Results revealed a broad pH niche for O. acidotolerans, with growth rates peaking at moderately acidic conditions (pH 5.2). Cyst formation was positively and linearly related to pH. Urosomoida sp. was more sensitive to pH and did not survive at circumneutral pH. Accordingly, we reject our hypothesis that similar habitats would harbour ciliate species with virtually identical pH reaction norm.

Bromeliothrix metopoides, a boom and bust ciliate (Ciliophora, Colpodea) from tank bromeliads

We investigated the recently described colpodid ciliate Bromeliothrix metopoides in a series of laboratory experiments to reveal the environmental factors that constrain this species to its peculiar habitat, i.e. the tanks of bromeliads. Our results demonstrated that the various life stages of this ciliate (bacterivorous theronts and microstome trophonts, flagellate-feeding macrostomes) have specific demands in terms of food quality and quantity. Bromeliothrix required a high food threshold (>1.4 mg C L⁻¹) in order to thrive. Food quality also affected resting cyst formation of B. metopoides when the experimental containers dried out. Its maximum growth rates (μ_max = 4.71 d⁻¹, i.e. 6.8 doublings d⁻¹) belong to the highest ones recorded thus far for free-living ciliates. The pH niche of B. metopoides was relatively wide (pH ∼4 to >9) under optimal food conditions. However, its high sensitivity to unfavourable environmental conditions let the population collapse within several hours. We conclude that B. metopoides is a boom and bust ciliate that is specifically adapted to its peculiar habitat but virtually unviable in other environments.

[Comparison of different electrocardiographic techniques for the detection of arrhythmias in horses]

OBJECTIVE

The aim of the study was to extend the range of the electrocardiographic examination in horses, evaluating the practicability of special electrocardiographic techniques (exercise- and Holter-ECG) and comparing these with more common techniques (resting-ECG) in equine medicine.

MATERIAL AND METHODS

Electrocardiographic examination (resting-ECG for 1 minute, exercise-ECG and Holter-ECG) was performed in 20 horses without any clinical or echocardiographic findings and in 80 patients with abnormal findings (valvular regurgitation and/or atrial fibrillation).

RESULTS

In comparison with the resting-ECG, the exercise-ECG demonstrated more atrial and ventricular premature beats, while the Holter-ECG had a higher detection rate of 2nd degree atrioventricular or sinuatrial blocks, and of ventricular and atrial premature depolarisations (p < 0.001). In comparison to the exercise-ECG, the Holter-ECG registered more 2nd degree atrioventricular blocks (p < 0.001) and ventricular (p < 0.001) or atrial premature contractions (p < 0.01). Atrial fibrillation was detected in every recorded ECG-type, but Holter-ECG provided additional information. Three of 16 horses with atrial fibrillation had R-on-T-episodes during Holter-monitoring. In addition to more common findings in the ECG, Holter-monitoring detected a 2nd degree atrioventricular block associated with an adjacent ventricular escape beat in a horse without any clinical or echocardiographic findings. An accelerated idioventricular rhythm was identified in a horse without any clinical or echocardiographic findings and in a horse with mitral valve insufficiency.

CONCLUSION AND CLINICAL RELEVANCE

The Holter-ECG is a useful tool in the evaluation of heart disease and could supply additional information when compared to the usual diagnostic electrocardiographic procedures used in horses. Exercise-ECG should not be replaced by Holter-ECG, however, Holter-EGC can provide additional diagnostic value.

Vergleichende Untersuchung von elektrokardiographischen Techniken zur Diagnostik von Herzrhythmusstörungen beim Pferd

Das Ziel dieser Studie war, die Befunde des Langzeit-EKGs beim Pferd mit denen des Belastungs- und des Ruhe-EKGs zu vergleichen. Material und Methode: Zwanzig klinisch und echokardiographisch unauffällige Kontrolltiere und 80 Patienten mit Klappeninsuffizienzen und/oder Vorhofflimmern wurden elektrokardiographisch untersucht. Die elektrokardiographischen Aufzeichnungen umfassten ein einminütiges Ruhe-EKG, ein Belastungs-EKG an der Longe und ein Langzeit-EKG über 24 Stunden. Ergebnisse: Im Vergleich zum Ruhe-EKG wurden Vorhof- und ventrikuläre Extrasystolen mithilfe des Belastungs-EKGs signifikant (p < 0,001) häufiger erkannt. Anhand des Langzeit-EKGs konnten signifikant mehr AV-Blöcke 2. Grades, sinuatriale Blöcke sowie Vorhof- und ventrikuläre Extrasystolen festgestellt werden als mithilfe des Ruhe-EKGs (p < 0,001). Beim Vergleich zwischen Belastungs-EKG und Langzeit-EKG zeigten sich im Langzeit-EKG signifikant häufiger AV-Blöcke 2. Grades (p < 0,001) sowie Extrasystolen atrialen (p < 0,001) und ventrikulären Ursprungs (p < 0,01). Vorhofflimmern wurde mit allen drei EKG-Techniken erfasst. Mittels Langzeit-EKG ließen sich allerdings neben dem Vorhofflimmern weitere elektrokardiographische Befunde erheben. Drei Tiere mit Vorhofflimmern zeigten zusätzlich das R-auf-T-Phänomen. Bei einem Pferd ohne klinische und echokardiographische Befunde traten im Langzeit-EKG Phasen mit je einem ventrikulären Ersatzschlag direkt nach einem AV-Block 2. Grades auf. Außerdem zeigten ein Kontrolltier und ein Pferd mit Mitralklappeninsuffizienz einen akzelerierten idioventrikulären Rhythmus. Schlussfolgerung und klinische Relevanz: Insgesamt erscheint es sinnvoll, das Langzeit-EKG wegen seines zusätzlichen Informationsgehalts in der Diagnostik von Herzerkrankungen häufiger anzuwenden als bisher üblich. Dabei sollte jedoch das Belastungs-EKG nicht ersetzt, sondern durch die Informationen des Langzeit-EKGs ergänzt werden.

Analyses of pig genomes provide insight into porcine demography and evolution

For 10,000 years pigs and humans have shared a close and complex relationship. From domestication to modern breeding practices, humans have shaped the genomes of domestic pigs. Here we present the assembly and analysis of the genome sequence of a female domestic Duroc pig (Sus scrofa) and a comparison with the genomes of wild and domestic pigs from Europe and Asia. Wild pigs emerged in South East Asia and subsequently spread across Eurasia. Our results reveal a deep phylogenetic split between European and Asian wild boars ∼1 million years ago, and a selective sweep analysis indicates selection on genes involved in RNA processing and regulation. Genes associated with immune response and olfaction exhibit fast evolution. Pigs have the largest repertoire of functional olfactory receptor genes, reflecting the importance of smell in this scavenging animal. The pig genome sequence provides an important resource for further improvements of this important livestock species, and our identification of many putative disease-causing variants extends the potential of the pig as a biomedical model.

Current trends in the diagnosis of vascular prosthesis infection

Early diagnosis of an infected vascular prosthesis, a potentially life-threatening disease, is a precondition of adequate treatment. The most frequently used diagnostic imaging method is computer tomography. Non-acute infections caused by low grade agents may pose a challenge with ambiguous CT-images and other ancillary imaging methods are used for these cases, each offering different levels of diagnostic sensitivity. These methods come from the fields of radiology (magnetic resonance imaging - MRI) and nuclear medicine studies using labelled leukocytes (111In or 99mTc HMPAO), 99mTc labelled antigranulocyte antibodies, 67Ga-citrate or labelled antibiotics (99mTc-ciprofloxacin) or avidin in combination with 111In-biotin. Positron emission tomography (PET) or hybrid PET/CT using 18F-FDG are becoming increasingly popular. The authors of this review article point out the diagnostic potential of the different methods and current trends, including the possibilities of microbiological demonstration of the agent, as well as their potential position in the diagnostic algorithm.

High mobility, low voltage operating C(60) based n-type organic field effect transistors

We report on C(60) based organic field effect transistors (OFETs) that are well optimized for low voltage operation. By replacing commonly used dielectric layers by thin parylene films or by utilizing different organic materials like divinyltetramethyldisiloxane-bis(benzocyclo-butene) (BCB), low density polyethylene (PE) or adenine in combination with aluminum oxide (AlOx) to form a bilayer gate dielectric, it was possible to significantly increase the capacitance per unit area (up to two orders of magnitude). The assembly of metal-oxide and organic passivation layer combines the properties of the high dielectric constant of the metal oxide and the good organic-organic interface between semiconductor and insulator provided by a thin capping layer on top of the AlOx film. This results in OFETs that operate with voltages lower than 500 mV, while exhibiting field effect mobilities exceeding 3 cm(2) V(-1) s(-1).