Logical quantum processor based on reconfigurable atom arrays

Suppressing errors is the central challenge for useful quantum computing1, requiring quantum error correction (QEC)2-6 for large-scale processing. However, the overhead in the realization of error-corrected 'logical' qubits, in which information is encoded across many physical qubits for redundancy2-4, poses substantial challenges to large-scale logical quantum computing. Here we report the realization of a programmable quantum processor based on encoded logical qubits operating with up to 280 physical qubits. Using logical-level control and a zoned architecture in reconfigurable neutral-atom arrays7, our system combines high two-qubit gate fidelities8, arbitrary connectivity7,9, as well as fully programmable single-qubit rotations and mid-circuit readout10-15. Operating this logical processor with various types of encoding, we demonstrate improvement of a two-qubit logic gate by scaling surface-code6 distance from d = 3 to d = 7, preparation of colour-code qubits with break-even fidelities5, fault-tolerant creation of logical Greenberger-Horne-Zeilinger (GHZ) states and feedforward entanglement teleportation, as well as operation of 40 colour-code qubits. Finally, using 3D [[8,3,2]] code blocks16,17, we realize computationally complex sampling circuits18 with up to 48 logical qubits entangled with hypercube connectivity19 with 228 logical two-qubit gates and 48 logical CCZ gates20. We find that this logical encoding substantially improves algorithmic performance with error detection, outperforming physical-qubit fidelities at both cross-entropy benchmarking and quantum simulations of fast scrambling21,22. These results herald the advent of early error-corrected quantum computation and chart a path towards large-scale logical processors.

High-fidelity parallel entangling gates on a neutral-atom quantum computer

The ability to perform entangling quantum operations with low error rates in a scalable fashion is a central element of useful quantum information processing1. Neutral-atom arrays have recently emerged as a promising quantum computing platform, featuring coherent control over hundreds of qubits2,3 and any-to-any gate connectivity in a flexible, dynamically reconfigurable architecture4. The main outstanding challenge has been to reduce errors in entangling operations mediated through Rydberg interactions5. Here we report the realization of two-qubit entangling gates with 99.5% fidelity on up to 60 atoms in parallel, surpassing the surface-code threshold for error correction6,7. Our method uses fast, single-pulse gates based on optimal control8, atomic dark states to reduce scattering9 and improvements to Rydberg excitation and atom cooling. We benchmark fidelity using several methods based on repeated gate applications10,11, characterize the physical error sources and outline future improvements. Finally, we generalize our method to design entangling gates involving a higher number of qubits, which we demonstrate by realizing low-error three-qubit gates12,13. By enabling high-fidelity operation in a scalable, highly connected system, these advances lay the groundwork for large-scale implementation of quantum algorithms14, error-corrected circuits7 and digital simulations15.

Comparison of serum protein profiles of Borrelia burgdorferi-positive Bernese Mountain Dogs and dogs of other breeds using MALDI-TOF technique

The aim of the study was to compare the serum protein profile of Bernese Mountain Dogs (BMDs) reacting positive for Bb in snap testing with the serum protein profile of dogs of other breeds (healthy and with clinical borreliosis) using the MALDI time-of-flight (MALDI-TOF) technique. The observations included five groups of dogs. BMDs reacting positively to Bb in snap serological testing and showing symptoms of borreliosis (group 1), BMDs for which no borreliosis symptoms were determined but with seropositivity for Bb determined with snap serological tests (group 2), clinically healthy BMDs with no antibodies for Bb found in the serum (group 3), five dogs of different breeds, reacting positively in serological testing, in which borreliosis symptoms were observed (group 4), clinically healthy dogs of different breeds with negative reaction in tests towards Bb (group 5). A proteomic analysis demonstrated the presence of five identical protein fractions among all five groups. An additional two protein fractions of approximately 7.630 and 15.260 kDa were found in all the serum samples obtained from the dogs positive for borrelia in a snap test, both in those exhibiting symptoms of borreliosis, and seropositive BMDs not presenting symptoms of the disease. These two additional protein fractions may be used to differentiate between seropositive and seronegative B. burgdorferi dogs and may be considered a seropositivity marker, however, it cannot be used to differentiate between animals with the clinical form of the disease and those that are only seropositive.

Fermionic quantum processing with programmable neutral atom arrays

Simulating the properties of many-body fermionic systems is an outstanding computational challenge relevant to material science, quantum chemistry, and particle physics.-5.4pc]Please note that the spelling of the following author names in the manuscript differs from the spelling provided in the article metadata: D. González-Cuadra, D. Bluvstein, M. Kalinowski, R. Kaubruegger, N. Maskara, P. Naldesi, T. V. Zache, A. M. Kaufman, M. D. Lukin, H. Pichler, B. Vermersch, Jun Ye, and P. Zoller. The spelling provided in the manuscript has been retained; please confirm. Although qubit-based quantum computers can potentially tackle this problem more efficiently than classical devices, encoding nonlocal fermionic statistics introduces an overhead in the required resources, limiting their applicability on near-term architectures. In this work, we present a fermionic quantum processor, where fermionic models are locally encoded in a fermionic register and simulated in a hardware-efficient manner using fermionic gates. We consider in particular fermionic atoms in programmable tweezer arrays and develop different protocols to implement nonlocal gates, guaranteeing Fermi statistics at the hardware level. We use this gate set, together with Rydberg-mediated interaction gates, to find efficient circuit decompositions for digital and variational quantum simulation algorithms, illustrated here for molecular energy estimation. Finally, we consider a combined fermion-qubit architecture, where both the motional and internal degrees of freedom of the atoms are harnessed to efficiently implement quantum phase estimation as well as to simulate lattice gauge theory dynamics.

Lyme disease in Bernese Mountain Dogs. Is it a real problem?

Borreliosis is the most frequently diagnosed tick-borne disease caused by spirochete bacteria belonging to the genus Borreliae - Borrelia burgdorferi sensu stricto (s.s.), Borrelia afzelii and Borrelia garinii. Clinical manifestations in dogs include fever, lameness, polyarthritis and glomerulonephritis. Diagnosis is mainly serological and is based on an immunoenzymatic test followed by a Western blot confirmatory test. Early treatment with antibiotics such as doxycycline or amoxicillin, for four weeks, usually reduces the risk of chronic disease. Tick control, including tick repellents, is highly reliable in preventing transmission. Vaccines are available to reduce transmission and the clinical manifestations of infection in dogs. Bernese Mountain Dogs are a breed that often test positive for antibodies against B. burgdorferi without showing any clinical symptoms of the disease. Quantitative determination of the immunoglobulin level for spirochetes has indicated that Bernese Mountain Dogs may have an increased susceptibility to Borrelia spp. infections of a hereditary nature.

Third international challenge to model the medium- to long-range transport of radioxenon to four Comprehensive Nuclear-Test-Ban Treaty monitoring stations

In 2015 and 2016, atmospheric transport modeling challenges were conducted in the context of the Comprehensive Nuclear-Test-Ban Treaty (CTBT) verification, however, with a more limited scope with respect to emission inventories, simulation period and number of relevant samples (i.e., those above the Minimum Detectable Concentration (MDC)) involved. Therefore, a more comprehensive atmospheric transport modeling challenge was organized in 2019. Stack release data of Xe-133 were provided by the Institut National des Radioéléments/IRE (Belgium) and the Canadian Nuclear Laboratories/CNL (Canada) and accounted for in the simulations over a three (mandatory) or six (optional) months period. Best estimate emissions of additional facilities (radiopharmaceutical production and nuclear research facilities, commercial reactors or relevant research reactors) of the Northern Hemisphere were included as well. Model results were compared with observed atmospheric activity concentrations at four International Monitoring System (IMS) stations located in Europe and North America with overall considerable influence of IRE and/or CNL emissions for evaluation of the participants' runs. Participants were prompted to work with controlled and harmonized model set-ups to make runs more comparable, but also to increase diversity. It was found that using the stack emissions of IRE and CNL with daily resolution does not lead to better results than disaggregating annual emissions of these two facilities taken from the literature if an overall score for all stations covering all valid observed samples is considered. A moderate benefit of roughly 10% is visible in statistical scores for samples influenced by IRE and/or CNL to at least 50% and there can be considerable benefit for individual samples. Effects of transport errors, not properly characterized remaining emitters and long IMS sampling times (12-24 h) undoubtedly are in contrast to and reduce the benefit of high-quality IRE and CNL stack data. Complementary best estimates for remaining emitters push the scores up by 18% compared to just considering IRE and CNL emissions alone. Despite the efforts undertaken the full multi-model ensemble built is highly redundant. An ensemble based on a few arbitrary runs is sufficient to model the Xe-133 background at the stations investigated. The effective ensemble size is below five. An optimized ensemble at each station has on average slightly higher skill compared to the full ensemble. However, the improvement (maximum of 20% and minimum of 3% in RMSE) in skill is likely being too small for being exploited for an independent period.

A quantum processor based on coherent transport of entangled atom arrays

The ability to engineer parallel, programmable operations between desired qubits within a quantum processor is key for building scalable quantum information systems^1,2. In most state-of-the-art approaches, qubits interact locally, constrained by the connectivity associated with their fixed spatial layout. Here we demonstrate a quantum processor with dynamic, non-local connectivity, in which entangled qubits are coherently transported in a highly parallel manner across two spatial dimensions, between layers of single- and two-qubit operations. Our approach makes use of neutral atom arrays trapped and transported by optical tweezers; hyperfine states are used for robust quantum information storage, and excitation into Rydberg states is used for entanglement generation^3–5. We use this architecture to realize programmable generation of entangled graph states, such as cluster states and a seven-qubit Steane code state^6,7. Furthermore, we shuttle entangled ancilla arrays to realize a surface code state with thirteen data and six ancillary qubits⁸ and a toric code state on a torus with sixteen data and eight ancillary qubits⁹. Finally, we use this architecture to realize a hybrid analogue–digital evolution² and use it for measuring entanglement entropy in quantum simulations^10–12, experimentally observing non-monotonic entanglement dynamics associated with quantum many-body scars^13,14. Realizing a long-standing goal, these results provide a route towards scalable quantum processing and enable applications ranging from simulation to metrology.

A quantum processer is realized using arrays of neutral atoms that are transported in a parallel manner by optical tweezers during computations, and used for quantum error correction and simulations.

Probing topological spin liquids on a programmable quantum simulator

[Figure: see text].

Babesia gibsoni infection in dogs in Poland

Canine babesiosis is a tickborne, protozoal, haemoparasitic disease. Babesia organisms are frequently classified as either large (B. canis) or small (B. gibsoni). The aim of this study was an attempt to detect B. gibsoni DNA in blood samples taken from dogs suspected of suffering from tick-borne diseases. 216 samples were tested using PCR, of which, in 99 of them B. canisDNA was detected, whereas in 3 of them B. gibsoni was detected. Positive PCR results for B. gibsoni were confirmed using a Qube MDx real-time analyzer. The results indicate that infec-tions with this B. gibsoni should be taken into account and included in the differential diagnosis of vector-borne diseases in dogs in Poland, and that the accurate identification of the species of parasite causing the infection is crucial for developing the correct treatment regimen and prognosis.

Tunable Three-Body Loss in a Nonlinear Rydberg Medium

Long-range Rydberg interactions, in combination with electromagnetically induced transparency (EIT), give rise to strongly interacting photons where the strength, sign, and form of the interactions are widely tunable and controllable. Such control can be applied to both coherent and dissipative interactions, which provides the potential for generating novel few-photon states. Recently it has been shown that Rydberg-EIT is a rare system in which three-body interactions can be as strong or stronger than two-body interactions. In this work, we study three-body scattering loss for Rydberg-EIT in a wide regime of single and two-photon detunings. Our numerical simulations of the full three-body wave function and analytical estimates based on Fermi's golden rule strongly suggest that the observed features in the outgoing photonic correlations are caused by the resonant enhancement of the three-body losses.

Granulocytic anaplasmosis in captive ring-tailed lemur (Lemur catta) in Poland

Background

Anaplasma are obligate intracellular bacteria and aetiological agents of tick-borne diseases of both veterinary and medical interest. The genus Anaplasma comprises six species: Anaplasma marginale, Anaplasma centrale, Anaplasma ovis, Anaplasma phagocytophilum, Anaplasma bovis and Anaplasma platys. They can infect humans, carnivores, ruminants, rodents, insectivores, birds and reptiles. The aim of this study was to present the first clinical case of granulocytic anaplasmosis in a captive ring-tailed lemur in Poland.

Case presentation

A 4-year-old female lemur presented anorexia, epistaxis and tick infestation. The microscopic examination of a blood smear revealed morulae in neutrophils. Polymerase chain reaction test and sequencing of obtained PCR product confirmed infection by the GU183908 Anaplasma phagocytophilum strain. Therapeutic protocol included doxycycline (2.5 mg/kg p.o., b.i.d.) for 3 weeks and the lemur recovered within 24 h.

Conclusions

This is the first report on granulocytic anaplasmosis in a ring-tailed lemur in Europe, indicating that A. phagocytophilum infection must also be considered in differential diagnosis in this animal species, especially in individuals with thrombocytopenia associated with Ixodes ricinus parasitism.

Molecular surveillance of tick-borne diseases affecting horses in Poland-Own observations

The purpose of the study was to carry out the molecular surveillance of piroplasmosis, granulocytic anaplasmosis and lyme borreliosis in horses which originated from Poland and exhibited symptoms raising the suspicion of the aforementioned disease units. The presence of Theileria equi genetic material was detected in 37 out of 512 examined horses (7.2%), and Anaplasma phagocytophilum in 9 (1.8%). The DNA of Borrelia burgdorferi was found in 11 out of 204 examined horses (5.4%). The above-cited results indicate that the problem of tick-borne diseases affecting horses in Poland is not as significant as in other parts of Europe, however they have to be considered in differential diagnosis of the diseases with lethargy, fever, anaemia and thrombocytopenia.

Molecular detection of Anaplasma phagocytophilum in roe deer (Capreolus capreolus) in eastern Poland

Wild ungulates may serve as reservoirs for particular tick-borne pathogens (TBP) of importance for public and animal health. The aim of the study was to investigate, for the first time, the occurrence of Anaplasma phagocytophilum (AP) in a large population of roe deer in eastern Poland. Spleen samples from 424 roe deer (Capreolus capreolus) were collected during the 2018-2019 hunting season. Genetic screening for AP was carried out by PCR amplification of a fragment of the 16S rRNA and groEL genes. Twenty-six of the 424 spleen samples (6.13%) tested positive both for 16S rRNA and groEL. Phylogenetic analysis confirmed the existence of a specific roe deer ecotype of AP in eastern Poland. Despite the low prevalence of AP in roe deer populations in the study area, these animals may act as anaplasmosis reservoirs for ticks. Based on the zoonotic potential of granulocytic anaplasmosis, it seems advisable to introduce continuous monitoring of this infection among domestic, farm and wild animals.

Economic development trends in the EU tourism industry. Towards the digitalization process and sustainability

From an economic viewpoint, tourism is heralded as bringing income to local communities. From an ecological standpoint, tourism poses a threat to environments. Sustainable tourism should leave a minimum negative impact on the places visited and preferably have rather positive impact on society. The digitization of the tourism economy is conducive to increasing the efficiency of enterprises operations, but also have positive impact on consumers. The objectives of the study are: to seek an answer to the question whether there is a relationship between the development of the tourism industry and GDP growth. Based on it there are two specific questions: What is a relationship between the level of development of digitization (e-commerce) and the development of the tourism industry and what is a relationship between the development of the tourism industry and sustainability factors? The originality of our research results among others results from three groups of variables use in the analysis (ICT group, SDG group and E&T group). Our research explores the factors affecting the tourism industry and relations of the digitization of tourism economy, sustainability and economy growth.

Exotic Photonic Molecules via Lennard-Jones-like Potentials

Ultracold systems offer an unprecedented level of control of interactions between atoms. An important challenge is to achieve a similar level of control of the interactions between photons. Towards this goal, we propose a realization of a novel Lennard-Jones-like potential between photons coupled to the Rydberg states via electromagnetically induced transparency (EIT). This potential is achieved by tuning Rydberg states to a Förster resonance with other Rydberg states. We consider few-body problems in 1D and 2D geometries and show the existence of self-bound clusters ("molecules") of photons. We demonstrate that for a few-body problem, the multibody interactions have a significant impact on the geometry of the molecular ground state. This leads to phenomena without counterparts in conventional systems: For example, three photons in two dimensions preferentially arrange themselves in a line configuration rather than in an equilateral-triangle configuration. Our result opens a new avenue for studies of many-body phenomena with strongly interacting photons.

Molecular analysis of the chromosomal 16S rRNA gene and vapA plasmid gene of Polish field strains of R. equi

Rhodococcus equi (R. hoagii) is an opportunistic pathogen commonly found in foals up to 6 months old and animal environment. The R. equi genome contains genetically stable chromosomal DNA and an 80–90 kb plasmid containing vapA gene, responsible for virulence. Most reports from around the world focus on the determination of R. equi plasmid profiles. Few studies have attempted to determine differences in nucleotide sequences between virulent strains of R. equi isolated from foals and breeding environment. The aim of the study was to perform a molecular analysis of a fragment of the chromosomal gene encoding the 16S rRNA subunit and the vapA plasmid gene of virulent R. equi strains isolated on Polish studs from foals and from the breeding environment of horses. The sequencing method was used to compare the primary structure of fragments of the chromosomal and plasmid DNA of the virulent R. equi strains. The sequences of 22 clinical and 18 environmental R. equi isolates were compared with the sequences of the gene fragments of reference strains available in the NCBI GenBank database. All sequenced 16S rRNA amplicons of Polish field strains were identical and showed 99.5% similarity to the four randomly selected sequences of this gene fragment in the GenBank database. The results confirm that fragments of the 16S rRNA gene of R. equi strains are highly conserved and do not undergo variation in field conditions. Analysis of the sequencing results for the vapA gene fragment of the strains used in our study revealed two polymorphic variants and clear differences between the sequences of strains isolated from foals and from soil samples. Presumably, R. equi strains present in the breeding environment are more exposed than clinical strains to adverse external factors. This may result in changes in the DNA sequence due to natural selection.

Long-range transport of Xe-133 emissions under convective and non-convective conditions

To investigate the transport of xenon emissions, the Provisional Technical Secretariat (PTS) operates an Atmospheric Transport Modelling (ATM) system based on the Lagrangian Particle Dispersion Model FLEXPART. The air mass trajectory ideally provides a "link" between a radionuclide release and a detection confirmed by radionuclide measurements. This paper investigates the long-range transport of Xe-133 emissions under convective and non-convective conditions, with special emphasis on evaluating the changes in the simulated activity concentration values due to the inclusion of the convective transport in the ATM simulations. For that purpose a series of 14 day forward simulations, with and without convective transport, released daily in the period from 1 January 2011 to 30 June 2013, were analysed. The release point was at the ANSTO facility in Australia. The simulated activity concentrations for the period January 2011 to February 2012 were calculated using the daily emission values provided by the ANSTO facility; outside the aforementioned period, the median daily emission value was used. In the simulations the analysed meteorological input data provided by the European Centre for Medium-Range Weather Forecasts (ECMWF) were used with the spatial resolution of 0.5°. It was found that the long-range transport of Xe-133 emissions under convective conditions, where convection was included in the ATM simulation, led to a small decrease in the activity concentration, as compared to transport without convection. In special cases related to deep convection, the opposite effect was observed. Availability of both daily emission values and measured Xe-133 activity concentration values was an opportunity to validate the simulations. Based on the paired t-test, a 95% confidence interval for the true mean difference between simulations without convective transport and measurements was constructed. It was estimated that the overall uncertainty lies between 0.08 and 0.25 mBq/m³. The uncertainty for the simulations with the convective transport included is slighted shifted to the lower values and is in the range between 0.06 and 0.20 mBq/m³.

Quality of fresh and chilled-stored raccoon dog semen and its impact on artificial insemination efficiency

Background

The aim of the study was to evaluate the quality of fresh raccoon dog semen and raccoon dog semen stored at 4 °C. The qualitative evaluation was based on apoptosis in the sperm cells, which was tested by the Annexin V/Pi assay, the TUNEL method and JC-1. In addition, the suitability of the semen for insemination and its effect on reproduction in females were determined in relation to the time of storage.

Results

During cold storage of the semen, in the samples from all groups a gradual decrease was noted in the percentage of live cells, and an increase in the percentage of cells with abnormal morphology, exhibiting changes typical of late-stage apoptosis (V⁺/PI⁺), and of necrotic cells (V⁻/PI⁺). There was a significant increase in the percentage of ApoBrDu + sperm cells, while the mitochondrial membrane potential of the sperm decreased significantly after 12 h of storage at 4 °C in the case of lower-quality semen and after 48 h in the case of semen of good quality. As the percentage of sperm with DNA and cell membrane damage increased and the mitochondrial membrane potential decreased, there was an increase in AspAT and acrosin activity. The increase in the percentage of apoptotic sperm in the raccoon dog semen stored at 4 °C resulted in a decrease in the number of females with cubs.

Conclusions

Identification of apoptotic changes in sperm by flow cytometry using the annexin assay, the TUNEL assay and evaluation of mitochondrial membrane potential can be recommended for determination of the suitability of raccoon dog semen for artificial insemination. The study shows that fresh raccoon dog semen should not be used for insemination more than 48 h after collection in the case of semen of very high quality, or after more than 24 h in the case of semen of poorer quality. Cytometric methods of semen analysis should also be used to evaluate various extenders of raccoon dog semen and methods of cryopreservation in terms of ensuring sperm viability, fertilization capacity, and suitability for insemination.

The effect of feed supplementation with zinc chelate and zinc sulphate on selected humoral and cell-mediated immune parameters and cytokine concentration in broiler chickens

The ability of poultry to withstand infectious disease caused by bacteria, viruses or protozoa depends upon the integrity of the immune system. Zinc is important for proper functioning of heterophils, mononuclear phagocytes and T lymphocytes. Numerous data indicate that the demand for zinc in poultry is not met in Poland due to its low content in feeds of vegetable origin. The aim of the study was to determine the effect of supplementation of inorganic (ZnSO₄ and ZnSO₄⁺ phytase enzyme), and organic forms of zinc (Zn with glycine and Zn with glycine and phytase enzyme) on selected parameters of the cellular and humoral immune response in broiler chickens by evaluating the percentage of CD3⁺CD4⁺, CD3⁺CD8⁺, CD25⁺, MHC Class II, and BU-1⁺ lymphocytes, the phagocytic activity of monocytes and heterophils, and the concentration of IL-2, IL-10 and TNF-α in the peripheral blood. Flow cytometry was used to determine selected cell-mediated immune response parameters. Phagocytic activity in whole blood was performed using the commercial Phagotest kit (ORPEGEN-Pharma, Immuniq, Poland). The results showed that supplementation with zinc chelates causes activation of the cellular and humoral immune response in poultry, helping to maintain the balance between the Th1 and Th2 response and enhancing resistance to infections. In contrast with chelates, the use of zinc in the form of sulphates has no immunomodulatory effect and may contribute to the development of local inflammatory processes in the digestive tract, increasing susceptibility to infection.

Tolerability and Adherence Problems in Patients on a Stable Dose of Methotrexate: Results of a Multicentre Survey

INTRODUCTION

Methotrexate is commonly used in patients with inflammatory arthritis. The aim of the present study was to ascertain the prevalence of side effects that patients on methotrexate were tolerating and to establish their adherence to the medication.

METHOD

A questionnaire was developed for completion by the healthcare professional with the patient, and piloted in one centre. The questionnaire was then used in six other centres, with the addition of a question about the attractiveness of stopping methotrexate treatment. Efficacy and toxicities were scored for severity on a 10-cm visual analogue scale (VAS). Adherence to the drug was also explored.

RESULTS

The prevalence of 'any side effect' ranged from 57% to 86%. The most frequent side effects were fatigue (53%); nausea (38%); mouth ulcers (23%) and hair loss (23%). Efficacy averaged 6.5 cm on the VAS. Results from the combined survey revealed that toxicity averaged 5.9 cm for fatigue, 4.8 cm for nausea, 4.4 for mouth ulcers, 3.9 cm for hair loss and 5.7 cm for 'other' side effects. 13.5% of patients revealed that they had forgotten to take the drug for an average of two weeks, and 25% for an average of 2.5 weeks in the previous year. Participants were more likely to reveal this to a nurse than a doctor.

CONCLUSION

Patients put up with a considerable number of side effects in order to benefit from methotrexate therapy. Adherence to this drug merits further study. Copyright © 2015 John Wiley & Sons, Ltd.

Effects of feed supplementation with glycine chelate and iron sulfate on selected parameters of cell-mediated immune response in broiler chickens

Because little is known about the impact of chelated (Fe-Gly, Fe-Gly+F) and inorganic (FeSO4, FeSO4+F) iron products on immune response parameters in broiler chickens, the objective of the study was to determine the effects of inorganic and organic forms of iron on selected parameters of the cell-mediated immune response in broiler chickens by assessing the percentage of CD3(+)CD4(+), CD3(+)CD8(+), CD25(+), and MHC Class II lymphocytes, as well as the CD4(+)/CD8(+) ratio and IL-2 concentration in the peripheral blood. The experiments were conducted using 50day-old Ross 308 roosters. The test material was peripheral blood. Flow cytometry was used to determine selected cell-mediated immune response parameters. The results obtained indicate that the use of iron chelates in the diet of broiler chickens may stimulate cellular defense mechanisms. As a result of the experiment an increase was observed in the percentage of Th1, mainly T CD4(+) and T CD8(+). It was also noted that application of chelated iron can increase production of T CD8(+) cytotoxic cells and IL-2, which promotes the body's natural response to developing inflammation. There were no changes in T CD4(+), T CD8(+), T CD25(+) or MHC II lymphocyte subpopulations in the chickens following application of the inorganic form of iron.

Plasmid Profiles of Virulent Rhodococcus equi Strains Isolated from Infected Foals in Poland

Rhodococcus equi is an important bacterial pathogen in foals up to 6 months old, widespread in horse farms all over the world. It was found that only virulent R. equi strains expressing 15–17 kDa virulence-associated protein (VapA) and having large virulence plasmid of 85–90 kb containing vapA gene are pathogenic for horses. To date, 12 plasmid types have been reported in VapA positive strains from horses. There are no data concerning plasmid types of Polish field R. equi strains isolated from horses and horse farm environment. The aim of the study is to determine plasmid profiles of virulent R. equi strains isolated in Poland from dead foals as well as from soil samples taken from horse breeding farms. Plasmid profiles of 10 clinical strains derived from 8 farms and 11 environmental strains from 3 farms, confirmed as virulent by PCR, were compared with 12 reference strains containing the known plasmid size and type. Plasmid DNAs were analysed by digestion with the restriction endonucleases BamHI, EcoRI, EcoT22I, and HindIII for detailed comparison and estimation of plasmid sizes. The results of RFLP analysis revealed that all except one isolates used in the study are classified as VapA 85 kb type I plasmid. One strain harboured VapA 87 kb type I plasmid. This is the first report of plasmid types of Polish field R. equi strains. The results of our preliminary investigations on horse farms located in central and eastern Poland indicate that the virulent R. equi strains thus far isolated from diseased foals and horse farms environment represent a highly uniform plasmid pattern.

Detection of the bovine viral diarrhoea virus (BVDV) in young beef cattle in eastern and south-eastern regions of Poland

In view of the scarcity of information concerning viral diarrhoea virus (BVDV) infections in beef cattle in Poland, the aim of this study was to evaluate the presence of the BVDV in young beef cattle from selected herds in eastern and south-eastern regions of Poland. The material consisted of 78 sera obtained from beef cattle from 15 farms, aged 6-12 months. The anti-BVDV antibody level in the sera was estimated with an ELISA kit, and detection of the BVDV was carried out by standard PCR and one step Real-Time RT-PCR. The ELISA results showed a high degree (80%) of positivity in 5 of the 78 samples. In 7 samples the degree of positivity was in the very low range: < 40%. Of the 78 cDNA samples, the presence of genetic material with a length of 288 bp was found by standard PCR in 3 sera. The genetic material of BVDV was also found in the sera of the same three calves by Real-Time HRM PCR. BVDV infection in young beef cattle in south-eastern Poland is not a significant problem. This was confirmed by the positive ELISA results for 6.4% of the animals and the positive PCR results for 3.9%. The percentage of positive beef herds was about 8.6%. However, due to the severe nature of the disease and rapid transmission of the virus, regular monitoring of BVDV should be carried out.

Changes in selected subpopulations of lymphocytes in dogs infected with Babesia canis treated with imidocarb

OBJECTIVE

The purpose of this study was to track changes in selected subpopulations of lymphocytes in the blood of dogs infected with Babesia (B.) canis and treated with imidocarb.

MATERIAL AND METHODS

The study included 16 dogs divided into two groups. The first group (n = 6) consisted of healthy control animals. Dogs of the se- cond group (n = 10) were infected with B. canis and after establishment of the diagnosis each animal received a single dose of imido- carb (5 mg/kg). Flow cytometry was used to enumerate several immune cell phenotypes.

RESULTS

It was concluded that the invasion of B. canis contributes to the decreased percentage of CD3+, CD4+, CD8+, CD21+ lymphocytes in the blood of infected animals. The decreased level of tested subpopulations of lymphocytes in group 2 persisted for the entire 12-day period of the test. After the administration of imidocarb, each tested lymphocyte fraction in the blood of the dogs with babesiosis increased, but did not reach physiological values.

CONCLUSION

The presented results indicate that the resolution of clinical signs associated with babesiosis may be related to the stimulation and intensity of cellular immunity, dependent on the CD4+ T cells profile. After administration of imidocarb, the parasitemia is cleared which allows the recovery of the lymphocyte populations.

Atmospheric transport modelling of time resolved 133Xe emissions from the isotope production facility ANSTO, Australia

The verification of the Comprehensive Nuclear-Test Ban Treaty (CTBT) relies amongst other things on the continuous and worldwide monitoring of radioxenon. The characterization of the existing and legitimate background, which is produced mainly by nuclear power plants and isotope production facilities, is of high interest to improve the capabilities of the monitoring network. However, the emissions from legitimate sources can usually only be estimated. For this paper historic source terms of (133)Xe emissions from the isotope production facility at ANSTO, Sydney, Australia, have been made available in a daily resolution. Based on these high resolution data, different source term sets with weekly, monthly and yearly time resolution have been compiled. These different sets are then applied together with atmospheric transport modelling (ATM) to predict the concentration time series at two radioxenon monitoring stations. The results are compared with each other in order to examine the improvement of the prediction capability depending on the used time resolution of the most dominant source term in the region.

A presumptive case of cerebral babesiosis in a dog in Poland caused by a virulent Babesia canis strain

The aim of this paper was to present the first case of cerebral canine babesiosis due to infection by Babesia canis in a dog in Poland. A 5-year-old American Staffordshire Terrier was presented with an unusual clinical manifestation of acute babesiosis that included neurological signs and pancytopenia. Despite treatment the dog died. Diagnosis was based on microscopic examination of Giemsa-stained blood smears (detection of piroplasms in red blood cells) and post mortem examination of the brain by histopathology and PCR method. The amplified segment of the Babesia 18S RNA gene was sequenced. This enabled to determine that the cause of the disease had been the strain 18S RNA-B EU622793. This is one of two B. canis strains found endemically in Poland, which reveals a greater virulence than the strain 18S RNA-A EU622792. The described case indicates that this form of canine babesiosis should be taken into account in differential diagnosis in dogs exhibiting neurological symptoms, especially in the tick activity season.

[The importance of CT angiography for screening supra-aortic vascular damage in severely injured patients]

PURPOSE

Traumatic injury of supra-aortic vessels remains a challenge in the initial diagnostics of severely injured patients. The presented prospective study analyzed the impact of multislice computed tomography angiography (CTA) as the primary diagnostic method.

METHODS

Patients with the following criteria were included and screened for a dissection of the supra-aortic vessels: a) admission directly from the scene, b) resuscitation room treatment indicated by the official criteria of the DGU (German Society for the Surgery of Trauma), c) suspected blunt trauma to head or trunk as well as d) age over 16 years.

RESULTS

During a period of 18 months 374 patients were treated for blunt trauma in the resuscitation room. In 176 cases CTA of the supra-aortic vessels was performed and pathological findings were observed in 16 patients. In 4 cases (2%) a traumatic dissection of supra-aortal vessels was diagnosed and confirmed by magnetic resonance imaging (MRI). All patients received heparin in a PTT effective dosage for 2 weeks and after rehabilitation there were no neurologic deficits.

CONCLUSION

Traumatic supra-aortic dissection was found in 2% of cases in the presented study group. The mechanisms of injury were not distinct in this group. Essentially MSCT angiography screening was demonstrated to be a safe diagnostic tool.

Visfatin serum levels in chronic hepatitis C patients

Visfatin is a new adipokine involved in several processes. The data concerning visfatin in chronic hepatitis C (CHC) is small. To assess visfatin serum concentration and to study its association with biochemical and morphological features in CHC. Seventy nonobese patients with CHC (Group 1) confirmed by the presence of serum hepatitis C virus (HCV)-RNA and 20 healthy volunteers (Group 2), similar in age and BMI with normal fasting glucose and lipid profile were included. Visfatin was significantly increased in Group 1 compared with Group 2 (55.6 +/- 23.1 vs 23.7 +/- 3.8 ng/mL; P < 0.001). Visfatin was negatively associated with necro-inflammatory activity grade (r = -0.36; P = 0.007). The lowest levels were found in patients with the most advanced inflammation: grades 3-4 - 46.8 +/- 17.1, grade 2 - 52.6 +/- 18.4 and grade 1 - 75.2 +/- 27.6 ng/mL; P = 0.017. A significant difference was also shown comparing patients with minimal inflammatory activity to the rest of the cohort (P = 0.009). Visfatin receiver operating characteristic curve analysis for different necro-inflammatory activity - grade 1 vs grades 3-4 with area under the curve 0.81 indicated a good discriminant power for differentiation of moderate/severe inflammation, with the cut-off set at 57.6 ng/mL (sensitivity 75%, specificity 90%, positive predictive value 0.90, negative predictive value 0.75). Serum visfatin concentration increases significantly in CHC patients. These findings suggest that visfatin is important in the pathogenesis of the inflammatory process in CHC. Visfatin may play a dual role as a pro-inflammatory or/and protective factor. The measurement of visfatin serum concentration may serve as an additional tool in distinguishing more advanced grades of the necro-inflammatory activity.

Open diverticulectomy in a patient with a giant symptomatic retro-pancreatic duodenal diverticulum. A case report

Although often incidentally found, diverticular disease of the small bowel and duodenum may generate complications and impose surgical treatment. Diagnosis of small bowel diverticulosis is difficult because the clinical picture is usually ambiguous. We report a case of diverticulosis of the whole intestine including a giant symptomatic retro-pancreatic duodenal diverticulum in a 74-year-old patient who presented with recurrent episodes of abdominal pain, weight loss and intestinal obstruction. The diagnosis was made by MRI enteroclysis and endoscopy. Open diverticulectomy with choledochostomy and insertion of a T-tube was performed and resulted in a rapid improvement of the symptoms.

Classification of heterogeneous electron microscopic projections into homogeneous subsets

The co-existence of different states of a macromolecular complex in samples used by three-dimensional electron microscopy (3D-EM) constitutes a serious challenge. The single particle method applied directly to such heterogeneous sets is unable to provide useful information about the encountered conformational diversity and produces reconstructions with severely reduced resolution. One approach to solving this problem is to partition heterogeneous projection set into homogeneous components and apply existing reconstruction techniques to each of them. Due to the nature of the projection images and the high noise level present in them, this classification task is difficult. A method is presented to achieve the desired classification by using a novel image similarity measure and solving the corresponding optimization problem. Unlike the majority of competing approaches, the presented method employs unsupervised classification (it does not require any prior knowledge about the objects being classified) and does not involve a 3D reconstruction procedure. We demonstrate a fast implementation of this method, capable of classifying projection sets that originate from 3D-EM. The method's performance is evaluated on synthetically generated data sets produced by projecting 3D objects that resemble biological structures.

Use of the LMA-ProSeal® in an Experimental Pig Model - A Potential Animal Model for Laryngeal Mask Airway Research: Results of a Pilot Study

OBJECTIVE

In light of the increased use of the LMA-ProSeal (P-LMA) it seems desirable to consider the P-LMA for prolonged surgical cases or post-operative ventilation. Long-term use could carry the risk of serious complications. An experimental pig model could be used to gain basic knowledge about long-term use before conducting clinical trails. In this randomized controlled study we tested the hypothesis if prolonged positive pressure ventilation (PPV) with the P-LMA in the pig is possible.

METHODS

The P-LMA was used for airway maintenance under general anaesthesia and PPV in 15 German country pigs. Randomised into 3 groups, the animals were ventilated for 90, 150 and 390 minutes, respectively. Arterial blood gas measurements were used to determine adequacy of ventilation. Airway leak pressure (P (leak)) and maximum tidal volume (TV) were measured in the supine, lateral and prone positions. A bronchoscopic examination was performed to detect signs of aspiration.

RESULTS

Adequate ventilation was demonstrated both after 120 min (4.7 +/- 0.4 kPa) and 360 min (4.7 +/- 0.5 kPa). The corresponding PaO(2) at FiO(2) = 1.0 was 59 +/- 5 kPa and 64 +/- 10 kPa, respectively. The mean P (leak) was 34 +/- 7 cm H(2)O. Change of position did not result in any significant change in P(leak) or maximum TV kg (-1). There was no bronchoscopic evidence of aspiration in any pig.

CONCLUSION

It was possible to ensure sufficient PPV with the P-LMA in the pig over different periods of time and in different body positions without any complications of airway management. The P-LMA can be used for PPV in the pig for durations of up to 390 minutes. We conclude that investigations into the long-term use of the LMA can be carried out in a pig model.

Seltene Ursache chronisch rezidivierender Lungenembolien und pulmonal-arterieller Hypertonie

HISTORY AND CLINICAL FINDINGS

A 41-year-old man with known Klippel-Trenaunay syndrome was admitted to hospital because of progressive dyspnea on exertion. Examination on admission revealed the typical signs of Klippel-Trenaunay syndrome, predominantly of the left leg.

INVESTIGATIONS

D-dimers were significantly increased. Contrast-enhanced computed tomography of the chest revealed multiple small pulmonary arterial emboli in subsegmental arteries on both lungs. Pulmonary arterial digital subtraction angiography revealed extensive peripherally localized perfusion defects. Pulmonary artery pressure measurement demonstrated bilateral pulmonary artery hypertension. Phlebography of the left lower leg showed marked varices in the calf. There was also a persisting sciatic vein.

DIAGNOSIS, TREATMENT AND COURSE

The recurrent peripheral pulmonary emboli with pulmonary arterial hypertension was a complication of a Klippel-Trenaunay syndrome. Another rare entity of this syndrome was a persisting sciatic vein. Heparinization was initiated, followed by oral anticoagulation. As the patient had not been anticoagulated before, implantation of an inferior vena cava filter was not deemed appropriate.

CONCLUSIONS

Recurrent peripheral pulmonary emboli leading to chronic pulmonary artery hypertension is a rare but typical complication of Klippel-Trenaunay syndrome. Early recognition of this syndrome and any complications as a separate entity, as well as initiation of therapeutic measures, like anticoagulation or early pulmonary thrombendarterectomy for chronic pulmonary artery emboli, are of prognostic importance.

[1-molar Gadobutrol as a contrast agent for digital subtraction angiography]

PURPOSE

To evaluate one-molar Gadobutrol solution as contrast media for intra-arterial digital subtraction angiography (DSA).

MATERIALS AND METHODS

In 10 patients (7 males, 3 females; mean age 68 years) with contraindications for the use of iodinated contrast media (n = 8 renal insufficiency, n = 2 previous allergic reaction), Gadobutrol solution (1 mol/l) was used as contrast media for DSA. Six diagnostic angiograms and four DSAs for percutaneous transluminal angioplasty (PTA) were performed.

RESULTS

In all cases, Gadobutrol yielded sufficient contrast for diagnostic DSA. Because of dose limitations (maximum 0.3 ml/kg body weight), small amounts of iodinated contrast media were administered to complete the angiographic procedure (mean 15 ml) in two patients. Allergic reactions were not recorded in any patient. In patients with pre-existing renal insufficiency, mean serum creatinine level was not statistically significant different from the initial level (mean 2.88 mg/dl before and 2.83 mg/dl after DSA). Selective injection of Gadobutrol resulted in temporary discomfort.

CONCLUSION

One molar Gadobutrol is an alternate contrast media for DSA in patients with contraindications for iodinated contrast media. Current dose limitations require selective injections.

Die transjuguläre Implantation venöser Portkathetersysteme

PURPOSE

Prospective analysis of success and complication rates of chest port implantation via the internal jugular vein.

MATERIALS AND METHODS

In 50 consecutive patients (25 men, 25 women; mean age 61 +/- 14 years) the internal jugular vein was punctured under ultrasound guidance. Through this access, a port system was inserted and the catheter tip was placed at the cavoatrial junction. The port reservoir was implanted into a subcutaneous infraclavicular pocket and fixed to the fascia of the pectoralis muscle. Indications for port implantation were chemotherapy (n = 46), total parenteral nutrition (n = 2) or intravenous medication (n = 2).

RESULTS

A chest port catheter system was successfully implanted in all 50 patients. The mean duration of placement was 90 +/- 65 catheter days. No complications occurred during implantation. In the post-interventional period a single catheter dysfunction occurred (0.22 per 1,000 catheter days). Two local infections occurred in the early post-interventional period (0.43 per 1,000 catheter days). One port system had to be explanted prematurely due to pain.

CONCLUSION

The ultrasound guided puncture of the internal jugular vein enables a safe access for insertion of a central venous port catheter system and is associated with a very low complication rate. Port placement via this access vein should therefore be the primary treatment.

Rotational digital cholangiography (RDC) and 3D-cholangiography (3DC) for guidance of percutaneous biliary drainage procedures

PURPOSE

To evaluate whether RDC and 3DC help clarifying anatomic details in biliary duct disease and is useful for guidance of drainage procedures.

MATERIALS AND METHODS

RDC was conducted in 11 consecutive patients (8 male, 3 female, mean age 63 years). Nine patients underwent PTBD for malignant biliary duct stenosis, one patient because of ischemic stenosis after hepaticojejunostomy and one patient presented with an infected biloma. Images were obtained after initial bile duct puncture during single breath hold from 120 projection angles using a rotating C-arm. These images were immediately available and evaluated in order to facilitate the definitive drainage procedure. For additional 3D reconstruction, data were sent to a dedicated workstation and judged by a blinded observer.

RESULTS

The availability of a rotating data set of images was judged to be helpful in three patients with complex anatomical situations. Additionally, RDC holds the potential to reduce fluoroscopy time. 3DC allowed analysis of the hepatic bifurcation from different viewing angles in 10 cases with high spatial resolution (mean voxel size 480 micro micro m 3). This may allow a better classification of hilar obstructions according to our preliminary observations.

CONCLUSION

Images from RDC and 3DC are helpful in guiding PTBD procedures and for better diagnosis in selected patients with hilar biliary duct stenoses.

Comparative Trial of Local Pharmacotherapy withl-Arginine, r-Hirudin, and Molsidomine to Reduce Restenosis after Balloon Angioplasty of Stenotic Rabbit Iliac Arteries

PURPOSE

To determine if local application of L-arginine, r-hirudin, or molsidomine significantly reduces restenosis after balloon angioplasty in stenotic rabbit iliac arteries.

MATERIALS AND METHODS

Thirty-one male cholesterol-fed New Zealand white rabbits underwent balloon dilation of both common iliac arteries to induce arterial stenosis. Four weeks later, one stenotic iliac artery was simultaneously dilated and received local application of L-arginine (210 mg/mL, n = 7), r-hirudin (0.5 mg/mL, n = 8), or molsidomine (0.2 mg/mL, n = 8) with a channeled balloon catheter. On the contralateral side, 0.9% saline was injected as a control. In eight sham animals, saline was applied to one iliac artery and balloon dilation to only the contralateral artery. Six weeks after local treatment, vessels were harvested, and computerized morphometric and immunohistologic analyses were performed.

RESULTS

Application of drugs resulted in a significant reduction of neointimal area as follows: 53% with L-arginine (1.01 mm(2) vs. 2.17 mm(2), P <.05), 43% with molsidomine (1.04 mm(2) vs. 1.89 mm(2), P <.05), and 20% with r-hirudin (1.79 mm(2) vs. 2.24 mm(2), P <.05). Infusion of saline led to a significant increase (50%, 1.21 mm(2) vs. 1.93 mm(2), P <.05) in neointimal area compared with balloon dilation alone. Immunohistologic findings showed a significant reduction of macrophages (5.0% vs. 10.2%, P <.05) and proliferating cells (6.2% vs. 10.6%, P <.05) in the neointima after local application of L-arginine.

CONCLUSION

Reduction of neointimal area was significant for L-arginine and molsidomine but not for r-hirudin. Saline infusion caused significant arterial trauma, resulting in additional neointimal proliferation.