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Background/aim: To assess and compare measured ventilatory volumes (forced expiratory volume in 1 s (FEV 1 ), peak expirium flow (PEF) and maximal voluntary ventilation (MVV)), ventilatory function capacities (forced vital capacity (FVC) and vital capacity (VC)) and FEV 1 /VC ratio in a sample of power and endurance elite athletes and their age-matched and sex-matched sedentary control group., Methods: A cross-sectional study was applied on male elite athletes (n=470) who were classified according to the type of the predominantly performed exercise in the following way: group 1: endurance group (EG=270), group 2: power athletes group (SG=200) and group 3: sedentary control group (CG=100). The lung VC, FVC, FEV 1 , FEV 1 /FVC ratio, PEF and MVV were measured in all of the observed subjects, who were also classified with regard to body mass index (BMI) and the percentage of the body fat (BF%)., Results: The CG had the highest BF% value, while the endurance group had the lowest BMI and BF% value, which is significantly different from the other two groups (p<0.05). The observed values of VC, FVC and FEV 1 in the EG were significantly higher than those from the other two groups (p<0.05). There were no differences concerning the observed FEV 1 /FVC ratio., Conclusions: A continued endurance physical activity leads to adaptive changes in spirometric parameters (VC, FVC and FEV 1 ), highlighting the fact that there is a need for specific consideration of different respiratory 'pattern' development in different types of sport, which also has to be further evaluated., Competing Interests: Competing interests: None declared.

Single-particle diffraction from X-ray Free Electron Lasers offers the potential for molecular structure determination without the need for crystallization. In an effort to further develop the technique, we present a dataset of coherent soft X-ray diffraction images of Coliphage PR772 virus, collected at the Atomic Molecular Optics (AMO) beamline with pnCCD detectors in the LAMP instrument at the Linac Coherent Light Source. The diameter of PR772 ranges from 65-70 nm, which is considerably smaller than the previously reported ~600 nm diameter Mimivirus. This reflects continued progress in XFEL-based single-particle imaging towards the single molecular imaging regime. The data set contains significantly more single particle hits than collected in previous experiments, enabling the development of improved statistical analysis, reconstruction algorithms, and quantitative metrics to determine resolution and self-consistency.

This study explores the capabilities of the Coherent X-ray Imaging Instrument at the Linac Coherent Light Source to image small biological samples. The weak signal from small samples puts a significant demand on the experiment. Aerosolized Omono River virus particles of ∼40 nm in diameter were injected into the submicrometre X-ray focus at a reduced pressure. Diffraction patterns were recorded on two area detectors. The statistical nature of the measurements from many individual particles provided information about the intensity profile of the X-ray beam, phase variations in the wavefront and the size distribution of the injected particles. The results point to a wider than expected size distribution (from ∼35 to ∼300 nm in diameter). This is likely to be owing to nonvolatile contaminants from larger droplets during aerosolization and droplet evaporation. The results suggest that the concentration of nonvolatile contaminants and the ratio between the volumes of the initial droplet and the sample particles is critical in such studies. The maximum beam intensity in the focus was found to be 1.9 × 10 12 photons per µm 2 per pulse. The full-width of the focus at half-maximum was estimated to be 500 nm (assuming 20% beamline transmission), and this width is larger than expected. Under these conditions, the diffraction signal from a sample-sized particle remained above the average background to a resolution of 4.25 nm. The results suggest that reducing the size of the initial droplets during aerosolization is necessary to bring small particles into the scope of detailed structural studies with X-ray lasers.

Rheumatoid arthritis (RA) is one of the most prevalent inflammatory rheumatic diseases. As it is a chronic and a lifelong destructive disease, the aim of the treatment is to reduce disability and improve quality of life. The Rheumatoid Arthritis Quality of Life (RAQoL) questionnaire is a patient-reported outcome measure, specific to RA. To adapt and validate the RAQoL for use in Serbia, two translation panels were involved to produce the Serbian RAQoL. After successful translation, face and content validity was determined via cognitive debriefing interviews. The psychometric properties of the questionnaire were examined, including reliability and construct validity, by using the Nottingham Health Profile (NHP) as a comparator scale. The RAQoL was translated successfully and rated as applicable, relevant and comprehensive by respondents. The questionnaire had high internal consistency (alpha = 0.94 at both time points) and test-retest reliability (r = 0.92). Moderately high correlations were found between the RAQoL and physical mobility, pain and energy level sections of the NHP, providing evidence of convergent validity. The RAQoL was able to distinguish between patients grouped by perceived general health, incidence of flare-up and disease severity. The Serbian language version of the RAQoL showed strong evidence of reliability and validity and is recommended for use in clinical trials and routine general practice in RA.

Introduction: The major oxygen sensors in the human body are peripheral chemoreceptors. also known as interoreceptors- as connected with internal organs, located in the aortic arch and in the body of the common carotid artery. Chemoreceptor function under physiological conditions. Stimulation of peripheral chemoreceptors during enviromental hypoxia causes a reflex-mediated increased ventilation, followed by the increase of the muscle sympatic activity, aiming to maintain tissue oxygen homeostatis, as well as glucosae, homeostatis. Besides that, peripheral chemoreceptors interact with central chemoreceptors. responsible for carbon dioxide changes . and they are able to modulate each other. Chemoreceptor function in pathophysiological conditions. Investigations of respiratory function in many pathological processes, such as hypertension, obstructive sleep apnea, congestive heart failure and many other diseases that are presented with enhanced peripheral chemosensitivity and impaired functional sy mpatholysis ultimately determine the peripheral chemorcceptor role and significance of peripheral chemoreceptors in the process of those pathological conditions development. Considering this, the presumed influence of peripheral chemoreceptors is important in patients having the above mentioned pathology., Conclusion: The importance and the role of peripheral chemoreceptors in the course of the breathing control is still controversial, despite many scientific attempts to solve this problem. The main objective of this review is to give the latest data on the peripheral chemoreceptor role and to highlight the importance of peripheral chemoreceptors for maintaining of oxygen homeostasis in pateints with hypoxia caused by either physiological or pathological conditions.

Omono River virus (OmRV) is a double-stranded RNA virus isolated from Culex mosquitos, and it belongs to a group of unassigned insect viruses that appear to be related to Totiviridae. This paper describes electron cryo-microscopy (cryoEM) structures for the intact OmRV virion to 8.9 Å resolution and the structure of the empty virus-like-particle, that lacks RNA, to 8.3 Å resolution. The icosahedral capsid contains 120-subunits and resembles another closely related arthropod-borne totivirus-like virus, the infectious myonecrosis virus (IMNV) from shrimps. Both viruses have an elevated plateau around their icosahedral 5-fold axes, surrounded by a deep canyon. Sequence and structural analysis suggests that this plateau region is mainly composed of the extended C-terminal region of the capsid proteins. In contrast to IMNV, the infectious form of OmRV lacks extensive fibre complexes at its 5-fold axes as directly confirmed by a contrast-enhancement technique, using Zernike phase-contrast cryo-EM. Instead, these fibre complexes are replaced by a short "plug" structure at the five-fold axes of OmRV. OmRV and IMNV have acquired an extracellular phase, and the structures at the five-fold axes may be significant in adaptation to cell-to-cell transmission in metazoan hosts.

Free-electron lasers (FEL) hold the potential to revolutionize structural biology by producing X-ray pules short enough to outrun radiation damage, thus allowing imaging of biological samples without the limitation from radiation damage. Thus, a major part of the scientific case for the first FELs was three-dimensional (3D) reconstruction of non-crystalline biological objects. In a recent publication we demonstrated the first 3D reconstruction of a biological object from an X-ray FEL using this technique. The sample was the giant Mimivirus, which is one of the largest known viruses with a diameter of 450 nm. Here we present the dataset used for this successful reconstruction. Data-analysis methods for single-particle imaging at FELs are undergoing heavy development but data collection relies on very limited time available through a highly competitive proposal process. This dataset provides experimental data to the entire community and could boost algorithm development and provide a benchmark dataset for new algorithms.

Single particle diffractive imaging data from Rice Dwarf Virus (RDV) were recorded using the Coherent X-ray Imaging (CXI) instrument at the Linac Coherent Light Source (LCLS). RDV was chosen as it is a well-characterized model system, useful for proof-of-principle experiments, system optimization and algorithm development. RDV, an icosahedral virus of about 70 nm in diameter, was aerosolized and injected into the approximately 0.1 μm diameter focused hard X-ray beam at the CXI instrument of LCLS. Diffraction patterns from RDV with signal to 5.9 Ångström were recorded. The diffraction data are available through the Coherent X-ray Imaging Data Bank (CXIDB) as a resource for algorithm development, the contents of which are described here.

Ultra-intense femtosecond X-ray pulses from X-ray lasers permit structural studies on single particles and biomolecules without crystals. We present a large data set on inherently heterogeneous, polyhedral carboxysome particles. Carboxysomes are cell organelles that vary in size and facilitate up to 40% of Earth's carbon fixation by cyanobacteria and certain proteobacteria. Variation in size hinders crystallization. Carboxysomes appear icosahedral in the electron microscope. A protein shell encapsulates a large number of Rubisco molecules in paracrystalline arrays inside the organelle. We used carboxysomes with a mean diameter of 115±26 nm from Halothiobacillus neapolitanus. A new aerosol sample-injector allowed us to record 70,000 low-noise diffraction patterns in 12 min. Every diffraction pattern is a unique structure measurement and high-throughput imaging allows sampling the space of structural variability. The different structures can be separated and phased directly from the diffraction data and open a way for accurate, high-throughput studies on structures and structural heterogeneity in biology and elsewhere.

Structural studies on living cells by conventional methods are limited to low resolution because radiation damage kills cells long before the necessary dose for high resolution can be delivered. X-ray free-electron lasers circumvent this problem by outrunning key damage processes with an ultra-short and extremely bright coherent X-ray pulse. Diffraction-before-destruction experiments provide high-resolution data from cells that are alive when the femtosecond X-ray pulse traverses the sample. This paper presents two data sets from micron-sized cyanobacteria obtained at the Linac Coherent Light Source, containing a total of 199,000 diffraction patterns. Utilizing this type of diffraction data will require the development of new analysis methods and algorithms for studying structure and structural variability in large populations of cells and to create abstract models. Such studies will allow us to understand living cells and populations of cells in new ways. New X-ray lasers, like the European XFEL, will produce billions of pulses per day, and could open new areas in structural sciences.

Objectives: To distinguish patients (pts) with enthesitis having spondyloarthritis (SpA) from pts with enthesitis without SpA by ultrasound (US) enthesitis score., Methods: The study sample included 127 pts with enthesitis (76 pts with SpA, 26 pts with rheumatoid arthritis, 25 pts with mechanically-related enthesitis). The entheses of plantar fascia, Achilles, patellar, quadriceps and common extensor tendon on lateral epicondyle were examined by US. Two operators, blinded to clinical diagnosis and enthesitis symptoms, assessed enthesis thickness, echogenicity, enthesophytes, power Doppler signal and erosions. Logistic regression and receiver operating characteristic (ROC) curve analysis were used to determine the predictive value of each enthesitis lesion for diagnosis of SpA. The best predictive value for SpA was accomplished when absence and presence of increased thickness, hypoechogenicity and enthesophytes were scored as 0 and 1; absence and presence of PD and erosions were scored as 0 and 4. Belgrade Ultrasound Enthesitis Score (BUSES) represents a cumulative score of derived enthesitis lesion scores at examined entheses. Independent-samples t-test was used for BUSES comparison between pts with and without SpA. Validity of BUSES for SpA diagnosis was evaluated by sensitivity and specificity. Cut-off point was chosen as the smallest value with specificity of at least 90%. The reliability was analysed by intra-class-correlation coefficient (ICC)., Results: BUSES was 9.9 ± 12.4 (mean ± SD) in SpA pts and 3.1 ± 4.2 in pts without SpA (p<0.001). BUSES cut-off point ≥ 7 achieved excellent specificity (90.2%) and fair sensitivity (47.4%). ICC was 0.99., Conclusions: BUSES is highly specific, valid and reliable to identify patients with SpA.

We present a proof-of-concept three-dimensional reconstruction of the giant mimivirus particle from experimentally measured diffraction patterns from an x-ray free-electron laser. Three-dimensional imaging requires the assembly of many two-dimensional patterns into an internally consistent Fourier volume. Since each particle is randomly oriented when exposed to the x-ray pulse, relative orientations have to be retrieved from the diffraction data alone. We achieve this with a modified version of the expand, maximize and compress algorithm and validate our result using new methods.

There exists a conspicuous gap of knowledge about the organization of life at mesoscopic levels. Ultra-fast coherent diffractive imaging with X-ray free-electron lasers can probe structures at the relevant length scales and may reach sub-nanometer resolution on micron-sized living cells. Here we show that we can introduce a beam of aerosolised cyanobacteria into the focus of the Linac Coherent Light Source and record diffraction patterns from individual living cells at very low noise levels and at high hit ratios. We obtain two-dimensional projection images directly from the diffraction patterns, and present the results as synthetic X-ray Nomarski images calculated from the complex-valued reconstructions. We further demonstrate that it is possible to record diffraction data to nanometer resolution on live cells with X-ray lasers. Extension to sub-nanometer resolution is within reach, although improvements in pulse parameters and X-ray area detectors will be necessary to unlock this potential.

We use a Mach-Zehnder type autocorrelator to split and delay XUV pulses from the FLASH soft X-ray laser for triggering and subsequently probing the explosion of aerosolised sugar balls. FLASH was running at 182 eV photon energy with pulses of 70 fs duration. The delay between the pump-probe pulses was varied between zero and 5 ps, and the pulses were focused to reach peak intensities above 10¹⁶W/cm² with an off-axis parabola. The direct pulse triggered the explosion of single aerosolised sucrose nano-particles, while the delayed pulse probed the exploding structure. The ejected ions were measured by ion time of flight spectrometry, and the particle sizes were measured by coherent diffractive imaging. The results show that sucrose particles of 560-1000 nm diameter retain their size for about 500 fs following the first exposure. Significant sample expansion happens between 500 fs and 1 ps. We present simulations to support these observations.

The first hard X-ray laser, the Linac Coherent Light Source (LCLS), produces 120 shots per second. Particles injected into the X-ray beam are hit randomly and in unknown orientations by the extremely intense X-ray pulses, where the femtosecond-duration X-ray pulses diffract from the sample before the particle structure is significantly changed even though the sample is ultimately destroyed by the deposited X-ray energy. Single particle X-ray diffraction experiments generate data at the FEL repetition rate, resulting in more than 400,000 detector readouts in an hour, the data stream during an experiment contains blank frames mixed with hits on single particles, clusters and contaminants. The diffraction signal is generally weak and it is superimposed on a low but continually fluctuating background signal, originating from photon noise in the beam line and electronic noise from the detector. Meanwhile, explosion of the sample creates fragments with a characteristic signature. Here, we describe methods based on rapid image analysis combined with ion Time-of-Flight (ToF) spectroscopy of the fragments to achieve an efficient, automated and unsupervised sorting of diffraction data. The studies described here form a basis for the development of real-time frame rejection methods, e.g. for the European XFEL, which is expected to produce 100 million pulses per hour.

Objectives: to evaluate and compare Moll and Wright, ESSG and CASPAR criteria for psoriatic arthritis (PsA) classification., Patients and Methods: Study comprised 356 patients (pts): 120 PsA pts in the investigated group, 123 pts with rheumatoid arthritis (RA) and 113 pts with non-inflammatory musculoskeletal symptoms (NIMS) in two control groups. Clinical diagnosis was the gold standard. Moll and Wright, ESSG and CASPAR criteria were applied to all pts. Sensitivity was calculated for each of the classification criteria sets; specificity was assessed in relation to RA and to NIMS groups, separately. Concordance between the investigated criteria sets was determined., Results: Sensitivity was 91.7% for CASPAR, 85.8% for Moll and Wright and 63.3% for ESSG criteria. Specificity for Moll and Wright criteria was 100%, with relation to both RA and to NIMS group. Specificity of CASPAR criteria was 99.2% and 99.1%; specificity of ESSG criteria was 94.3% and 67%, with regard to RA and to NIMS groups, respectively. Significant fair concordance was found only between CASPAR and Moll and Wright criteria (k=0.379 p<0.001)., Conclusions: The highest sensitivity had the CASPAR criteria, followed by Moll and Wright and ESSG. The highest specificity showed Moll and Wright criteria, followed by CASPAR and ESSG. CASPAR criteria demonstrated high specificity when applied to both NIMS and RA group. The lowest specificity was found for the ESSG criteria in relation to NIMS group. The only significant concordance was shown between CASPAR and Moll and Wright criteria.

Introduction: Allopurinol is still the drug of choice for the long-term control of hyperuricemia in patients with gout. Objective The aim of the study was to investigate the efficacy and tolerability of different allopurinol doses used in order to attain a target serum uric acid concentration (SUc) of <6 mg/dl (360 micromol/L)., Methods: Prospective trial was carried out in patients with primary gout and normal renal function, no relevant liver disease, and SUc-lowering treatment indications involving 1-2 gout episodes per year, presence oftophus and/or chronic urate arthropathy or X-ray finding of erosions. The patients were administered allopurinol in a step-up dose scheme (beginning with 100 mg/ day then raised for 100 mg every four weeks) until therapeutic goal was achieved or development of adverse effects., Results: Forty-one patients were enrolled in the study; 27 ended it so far.The treatment target was reached in 19/27 patients using allopurinol 300 mg/day (70.4%). After the increased dose up to 600 mg/day, the overall treatment success was reached in 25/27 patients (92.5%). Adverse drug reactions (ADRs) were evidenced in 12/27 patients; the most frequent ADRs were gouty flares. The mean SUc reduction from baseline 533.9+/-83.4 micromol/L to 346.9+/-87.9 micromol/L was obtained with allopurinol at a dose of 300 mg/day (p=0.000) as well as at a dose up to 600 mg/day (274.9+/-92.7 micromol/L) (p=0.000)., Conclusions: Most of the investigated gouty patients attained target SUc <360 mmol/L at a 300 mg/day allopurinol dose. However, in 30% of patients further dose escalation up to 600 mg/day was needed but the increased dose was well tolerated, and the therapeutic goal was achieved even in 92.5% of patients. Such doses are in general well tolerated under the conditions of well preserved renal function.

Conflict of Interest: NONE DECLARED., Introduction: P-wave abnormalities on the resting electrocardiogram have been associated with cardiovascular or pulmonary disease. So far, "Gothic" P wave and verticalization of the frontal plane axis is related to lung disease, particularly obstructive lung disease., Aim: We tested if inverted P wave in AVl as a lone criteria of P wave axis >70° could be screening tool for emphysema., Material and Method: 1095 routine electrocardiograms (ECGs) were reviewed which yielded 478 (82,1%) ECGs with vertical P-axis in sinus rhythm. Charts were reviewed for the diagnosis of COPD and emphysema based on medical history and pulmonary function tests., Conclusion: Electrocardiogram is very effective screening tool not only in cardiovascular field but in chronic obstructive pulmonary disease. The verticality of the P axis is usually immediately apparent, making electrocardiogram rapid screening test for emphysema.

Introduction: There are 12 recommendations for gout treatment, based on evidence and opinion of experts., Objective: To assess the quality of therapy in patients with gout analyzing adherence to four selected recommendations., Methods: Retrospective cross sectional study of 111 patients with gouty flare was conducted. Adherence to selected recommendation was defined as odds ratio between the number of patients whose therapy adhered to treatment recommendation and the number of patients eligible for the relevant recommendation. These recommendations refer to indications for allopurinol treatment (R1), prophylaxis of induced gouty flares in the first month of allopurinol treatment (R2), treatment goals (R3), and treatment monitoring regime (R4)., Results: Out of 111 patients with gout, 25 with tophi, 87 with frequent gouty flares and 46 with CUA or X-ray erosions were indicated for allopurinol treatment. The adherence to R1 was 76% for tophi patients, 54% for patients with frequent gouty flares, and 63% for patients with CUA. None of the patients starting allopurinol was either recruited for gouty prophylaxis or monitored properly; adherence to R2 as well as to R4 was 0%. Target serum uric acid (SUc) rating below 360 micromol/L was achieved in 13/50 patients treated with allopurinol, while the adherence to R3 was 26%. Therapeutic monitoring in accordance with P4 was not done in any of the patients on allopurinol. There were no differences in mean levels of the SUc between allopurinol users and non-users: 471.3 +/- 164.4 vs. 460.0 +/- 103.5 micromol/L (p = 0.067). Therefore, almost every second patient with gouty flares was on allopurinol therapy (50/111)., Conclusion: The degree of deviation in relation to the key principles of correct treatment in patients with gout ranged from a relatively high (24%) to that of absolute digression (100%).

We describe femtosecond X-ray diffraction data sets of viruses and nanoparticles collected at the Linac Coherent Light Source. The data establish the first large benchmark data sets for coherent diffraction methods freely available to the public, to bolster the development of algorithms that are essential for developing this novel approach as a useful imaging technique. Applications are 2D reconstructions, orientation classification and finally 3D imaging by assembling 2D patterns into a 3D diffraction volume.

Single-particle experiments using X-ray Free Electron Lasers produce more than 10(5) snapshots per hour, consisting of an admixture of blank shots (no particle intercepted), and exposures of one or more particles. Experimental data sets also often contain unintentional contamination with different species. We present an unsupervised method able to sort experimental snapshots without recourse to templates, specific noise models, or user-directed learning. The results show 90% agreement with manual classification., (© 2011 Optical Society of America)

Introduction: About one half of the first gout attacks occur in the first metatarsophalangeal joint (MTPJ1); in the disease course this joint is practically inevitably affected. Radiographic evidence of bone erosions is the indication for hypouricaemic therapy in order to prevent joint destruction and nephropathy. Advantages of ultrasonography (US) comparing to conventional x-ray findings in depicting early bone erosions in various inflammatory arthropathies have been demonstrated by several studies., Objective: The aims of this study were to compare US and x-ray findings in the detection of MTPJ1 erosions in patients with gout, to correlate sonographic and clinical features, and to detect possible characteristic sonographic features of gout., Methods: Thirty patients (60 MTPJ1) with primary gout (ACR) and 10 age-matched control subjects (20 MTPJ1) with different inflammatory arthropathies were clinically evaluated. Standard dorsiplantar weight bearing and lateral weight bearing x-ray views of both feet were taken. US was performed and interpreted by an independent sonographer on the presence of bone erosions, synovial fluid, synovial hypertrophy, Doppler signal and hyperechoic spots. Statistical analysis was performed (Spearman and Pearson correlation coefficient, Wilcoxon and chi2 test.), Results: Twenty-four studied MTPJ1 had evidence of erosions, 17 only on US and seven both on x-ray and on US (Z = -4.123; p = 0.000). US findings showed that hyperechoic spots were the most prominent feature of gouty MTPJ1 (chi2 = 40.909; p = 0.000), followed by erosions and synovial fluid presentation., Conclusion: US of MTPJ1 in gout discovers significantly more erosions than x-ray, which may have therapeutic implications. The evidence of hyperechoic spots (surrogate crystals) of the different size, number and orientation is a major sonographic feature of the MTPJ1 in gout, which may be of importance in the diagnosis of certain cases (low serum urate, unavailable synovial fluid or the urate crystals absence).

X-ray crystallography provides the vast majority of macromolecular structures, but the success of the method relies on growing crystals of sufficient size. In conventional measurements, the necessary increase in X-ray dose to record data from crystals that are too small leads to extensive damage before a diffraction signal can be recorded. It is particularly challenging to obtain large, well-diffracting crystals of membrane proteins, for which fewer than 300 unique structures have been determined despite their importance in all living cells. Here we present a method for structure determination where single-crystal X-ray diffraction 'snapshots' are collected from a fully hydrated stream of nanocrystals using femtosecond pulses from a hard-X-ray free-electron laser, the Linac Coherent Light Source. We prove this concept with nanocrystals of photosystem I, one of the largest membrane protein complexes. More than 3,000,000 diffraction patterns were collected in this study, and a three-dimensional data set was assembled from individual photosystem I nanocrystals (∼200 nm to 2 μm in size). We mitigate the problem of radiation damage in crystallography by using pulses briefer than the timescale of most damage processes. This offers a new approach to structure determination of macromolecules that do not yield crystals of sufficient size for studies using conventional radiation sources or are particularly sensitive to radiation damage.

In nanotechnology, strategies for the creation and manipulation of nanoparticles in the gas phase are critically important for surface modification and substrate-free characterization. Recent coherent diffractive imaging with intense femtosecond X-ray pulses has verified the capability of single-shot imaging of nanoscale objects at suboptical resolutions beyond the radiation-induced damage threshold. By intercepting electrospray-generated particles with a single 15 femtosecond soft-X-ray pulse, we demonstrate diffractive imaging of a nanoscale specimen in free flight for the first time, an important step toward imaging uncrystallized biomolecules.

Objective: To adapt and validate a telephone questionnaire for case detection of rheumatoid arthritis (RA) and spondyloarthropathies (SpA) in the Serbian population., Methods: A questionnaire, developed by the French Society of Rheumatology and successfully tested in France, was adapted to the Serbian language using a cross-cultural adaptation process. It was validated in 150 patients: 50 with RA, 50 with SpA and 50 with degenerative rheumatic disorders. They were recruited from Institute of Rheumatology in Belgrade, hospital registry, years 2001 and 2002. The questionnaire validity was assessed in reference to clinical diagnosis and ACR 1987 and ESSG 1991 classification criteria. A logistic regression model was used for RA-control and SpA-control comparison to identify the set of items that best discriminates these groups., Results: Cross-cultural adaptation of the Questionnaire was successfully achieved, verifying its equivalence with the original (semantic, idiomatic, experiential, conceptual). According to the logistic regression, two items selected for RA provided 92.1% agreement when using either clinical diagnosis or ACR classification criteria as a standard. SpA-control comparison included five items providing 96.8% agreement with clinical diagnosis and four items providing 94.1% agreement with ESSG criteria. Results of the present study are similar to those found in the French study., Conclusion: Validation results of the telephone questionnaire, translated and adapted to the Serbian language, confirm that it can be used as a detection tool for RA and SpA cases in the population of Serbia, whose diagnoses would have to be further confirmed.

Cephamycin C-producing microorganisms use two enzymes to convert cephalosporins to their 7alpha-methoxy derivatives. Here we report the X-ray structure of one of these enzymes, CmcI, from Streptomyces clavuligerus. The polypeptide chain of the enzyme folds into a C-terminal Rossmann domain and a smaller N-terminal domain, and the molecule packs as a hexamer in the crystal. The Rossmann domain binds S-adenosyl-L-methionine (SAM) and the demethylated product, S-adenosyl-L-homocysteine, in a fashion similar to the common binding mode of this cofactor in SAM-dependent methyltransferases. There is a magnesium-binding site in the vicinity of the SAM site with a bound magnesium ion ligated by residues Asp160, Glu186 and Asp187. The expected cephalosporin binding site near the magnesium ion is occupied by polyethyleneglycol (PEG) from the crystallisation medium. The geometry of the SAM and the magnesium binding sites is similar to that found in cathechol O-methyltransferase. The results suggest CmcI is a methyltransferase, and its most likely function is to catalyse the transfer of a methyl group from SAM to the 7alpha-hydroxy cephalosporin in the second catalytic reaction of cephamycin formation. Based on the docking of the putative substrate, 7alpha-hydroxy-O-carbamoyldeacetylcephalosporin C, to the structure of the ternary CmcI-Mg2+-SAM complex, we propose a model for substrate binding and catalysis. In this model, the 7-hydroxy group of the beta-lactam ring ligates the Mg2+ with its alpha-side facing the methyl group of SAM at a distance that would allow methylation of the hydroxyl-group.

Cephamycins are broad-spectrum beta-lactam antibiotics that show resistance to certain forms of beta-lactamases. They differ from cephalosporins by the presence of a methoxyl group at the C-7alpha position. The gene products of cmcI and cmcJ are believed to control 7alpha-methoxylation of cephalosporins through successive steps of hydroxylation and methylation. Here, the expression, purification, crystallization and initial data-collection statistics of the 236-amino-acid protein product of cmcI from Streptomyces clavuligerus is reported. The crystals belong to space group P2(1), with unit-cell parameters a = 93.6, b = 182.6, c = 103.2 A, beta = 91.05 degrees. Diffraction data were collected to 2.5 A.

In this paper we show that the porcine rubulavirus LPMV phosphoprotein (P) and V protein (V) both interact with the nucleoprotein (NP). There are also indications for an interaction between P and V with L protein. Further analysis of the domains of the P and V which are necessary for interaction with the NP protein demonstrates that the interaction is not mediated from their common part but instead from their unique C-terminal parts, respectively. The common N-terminus of P and V appear to mediate the interaction with L. We also map the regions of NP that are necessary for interaction with P and V, respectively. Both P and V interact with regions of NP, which reside in the N-terminal part but appear not to overlap.

Complementary DNA clones representing the fusion (F) protein gene of the porcine rubulavirus LPMV were isolated and sequenced. The F gene was found to be 1,845 nucleotides long containing one long open reading frame capable of encoding a protein of 541 amino acids. The cleavage motif for F0 into F1 and F2 is His-Arg-Lys-Lys-Arg. A sequence comparison and a phylogenetic analysis was performed in order to identify possible functional domains of paramyxovirus fusion proteins and also to classify the porcine rubulavirus. The F gene of LPMV is most closely related to the human mumps virus and simian virus type 5 F genes, and is therefore classified into the rubulavirus genus. A coding region for a small hydrophobic protein was however not found between the F and hemagglutinin-neuraminidase (HN) genes as previously found in both SV5 and mumps.