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ABSTRACTA collaborative exercise is presented where different numerical methods were used to recreate the forces acting on a ship model while executing captive model tests along a channel which has an unsteady cross section (dock opening). Such a layout is typical for a harbour environment. The unsteady nature of the cross section leads to peak values in forces, sinkage and free surface deformations. Experimental tests were conducted by Flanders Hydraulics (with the co-operation of Ghent University). Numerical contributions involve three potential flow methods (Strathclyde University and Pinkster Marine Hydrodynamics) and one RANS method (Federal Waterways Engineering and Research Institute of Germany). All methods are capable of qualitatively predicting the water level variations and sinkage and trim of the vessel. RANS has a better capability of predicting the unsteady sway force and yaw moment acting on the ship including sinkage and trim, but it comes at a much higher computational cost.

The text includes a variety of letters and an opinion piece from the Polish American Journal. The opinion piece, written by Dr. Richard C. Lukas, discusses the divided opinions among Polish Americans regarding the choice for President of the United States. Lukas expresses his disbelief that some Polish Americans would choose an authoritarian leader over someone dedicated to democratic principles. He criticizes President Trump's personal and governmental record and highlights the dangers of Project 2025, a plan developed by the extreme right-wing Heritage Foundation to dismantle American democracy. The letters from readers express differing opinions on topics such as LGBT advertisements and the content of the journal. [Extracted from the article]

Dietary protein intake can significantly affect muscle enzyme and serum activity after acute exercise-induced muscle injury. An investigation of the effects of varying levels of dietary protein on the postexercise increase in serum and muscle enzyme activity usually seen after exercise-induced muscle injury has been carried out using rats.

The stereoselective synthesis of terminal bromo-substituted propargylamines via in situgeneration of lithium bromoacetylide from 1,2-dibromoethene and addition to Ellman chiral N-tert-butanesulfinyl aldimines is reported. Modest to good yields (43–85%) and diastereoselectivity (dr = 3:1 to >20:1) were achieved for a range of aryl, heteroaryl, alkyl, and α,β-unsaturated substrates. Terminal bromo-substituted propargylamines prepared via this method can be directly used in the frequently employed Cadiot–Chodkiewicz coupling to produce functionalized diynes. The method reported here increases the structural diversity of chiral terminal bromo-substituted propargylamines that can be readily synthesized as previous methods for the stereoselective synthesis of these compounds rely on amino acid precursors from the chiral pool.

To help understand how we came to where we are today, Table 1 and Figure 1 chart the longer term progress of the Michiana region, of which South Bend/Mishawaka and [...]

This study explores a non-kinase effect of ERK1/2 on the interaction between deoxyhypusine synthase (DHPS) and its substrate, eukaryotic translation initiation factor 5A (eIF5A). We report that Raf/MEK/ERK activation decreases DHPS-ERK1/2 interaction while increasing DHPS-eIF5A association in cells. We determined the cryo-EM structure of the DHPS-ERK2 complex at 3.5 Å to show that ERK2 hinders substrate entrance to the DHPS active site, subsequently inhibiting deoxyhypusination in vitro. In cells, impairing the ERK2 activation loop, but not the catalytic site, prolongs DHPS-ERK2 interaction irrespectively of Raf/MEK signaling. The ERK2 Ser-Pro-Ser motif, but not the common docking or F-site recognition sites, also regulates this complex. These data suggest that ERK1/2 dynamically regulates DHPS-eIF5A interaction in response to Raf/MEK activity, regardless of its kinase function. In contrast, ERK1/2 kinase activity is necessary to regulate the expression of DHPS and eIF5A. These findings highlight an ERK1/2-mediated dual kinase-dependent and -independent regulation of deoxyhypusination.

Deep brain stimulation (DBS) of the ventral capsule/ventral striatum (VC/VS) is effective for treatment-resistant obsessive-compulsive disorder (OCD); however, DBS is associated with neurosurgical risks. Transcranial focused ultrasound (tFUS) is a newer form of noninvasive (ie, nonsurgical) stimulation that can modulate deeper regions, such as the VC/VS. tFUS parameters have just begun to be studied and have often not been compared in the same participants. We explored the effects of three VC/VS tFUS protocols and an entorhinal cortex (ErC) tFUS session on the VC/VS and cortico-striato-thalamo-cortical circuit (CSTC) in healthy individuals for later application to patients with OCD.

ObjectiveWe aimed to identify predictors of left atrial appendage (LAA) thrombus in patients with atrial fibrillation (AF) and to enhance the prognostic value of the CHA2DS2-VASc score.MethodsDerivation cohort included 1033 consecutive AF patients referred for catheter ablation or direct current cardioversion, in whom transoesophageal echocardiography (TOE) was performed prior to the procedure. Logistic regression analysis was used to identify predictors of LAA thrombus on TOE. Receiver operating characteristic (ROC) curves were constructed to compare the newly developed score with the CHA2DS2and CHA2DS2-VASc scores in the derivation and the validation (n=320) cohort.ResultsOn TOE, LAA thrombus was present in 59 (5.7%) patients in the derivation cohort. Aside from variables encompassed by the CHA2DS2-VASc score, LAA thrombus predictors included AF type (persistent/’permanent’ vs paroxysmal) and renal dysfunction. These predictors were incorporated into the CHA2DS2-VASc score. In ROC analysis, area under the curve (AUC) for the new score (CHA2DS2-VASc-RAF score) was significantly higher (0.81) than those for the CHA2DS2and CHA2DS2-VASc scores (0.71 and 0.70, respectively). In the validation cohort, the CHA2DS2-VASc-RAF score also performed significantly better (AUC of 0.88) than the CHA2DS2and CHA2DS2-VASc scores (AUC of 0.63 and 0.60, respectively).ConclusionIn real-world AF patients with majority on oral anticoagulation, LAA thrombus was found in approximately 6%. Two variables not included in the CHA2DS2-VASc score (AF type and renal dysfunction) proved strong, independent predictors of LAA thrombus and might improve thromboembolic risk stratification.

•SMA3 leading to the biggest limitations in performing.•The most difficult tasks to perform were those in the area of ‘mobility’.•Patients from our study reported similar limitations in activities of daily living.

To help understand how we came to where we are today, Table 1 and Figure 1 provide data from 1994 to the middle of 2004 that chart the longer-term progress [...]

Nowadays, in positron emission tomography (PET) systems, a time of flight (TOF) information is used to improve the image reconstruction process. In TOF-PET, fast detectors are able to measure the difference in the arrival time of the two gamma rays, with the precision enabling to shorten significantly a range along the line-of-response (LOR) where the annihilation occurred. In the new concept, called J-PET scanner, gamma rays are detected in plastic scintillators. In a single strip of J-PET system, time values are obtained by probing signals in the amplitude domain. Owing to compressive sensing (CS) theory, information about the shape and amplitude of the signals is recovered. In this paper, we demonstrate that based on the acquired signals parameters, a better signal normalization may be provided in order to improve the TOF resolution. The procedure was tested using large sample of data registered by a dedicated detection setup enabling sampling of signals with 50-ps intervals. Experimental setup provided irradiation of a chosen position in the plastic scintillator strip with annihilation gamma quanta.

The polystyrene doped with 2,5-diphenyloxazole as a primary fluor and 2-(4-styrylphenyl)benzoxazole as a wavelength shifter prepared as a plastic scintillator was investigated using positronium probe in wide range of temperatures from 123 to 423 K. Three structural transitions at 260, 283, and 370 K were found in the material. In the o-Ps intensity dependence on temperature, the significant hysteresis is observed. Heated to 370 K, the material exhibits the o-Ps intensity variations in time.

Results of positron annihilation lifetime spectroscopy (PALS) and microscopic studies on simple microorganisms, brewing yeasts, are presented. Lifetime of ortho-positronium (o-Ps) were found to change from 2.4 to 2.9 ns (longer-lived component) for lyophilized and aqueous yeasts, respectively. Also hygroscopicity of yeasts in time was examined, allowing to check how water – the main component of the cell – affects PALS parameters, thus lifetime of o-Ps were found to change from 1.2 to 1.4 ns (shorter-lived component) for the dried yeasts. The time sufficient to hydrate the cells was found below 10 hours. In the presence of liquid water, an indication of reorganization of yeast in the molecular scale was observed. Microscopic images of the lyophilized, dried, and wet yeasts with best possible resolution were obtained using inverted microscopy (IM) and environmental scanning electron microscopy (ESEM) methods. As a result, visible changes to the surface of the cell me mbrane were observed in ESEM images.

Hundreds of molecular-level changes within central metabolism allow a cell to adapt to the changing environment. A primary challenge in cell physiology is to identify which of these molecular-level changes are active regulatory events. Here, we introduce pseudo-transition analysis, an approach that uses multiple steady-state observations of 13C-resolved fluxes, metabolites, and transcripts to infer which regulatory events drive metabolic adaptations following environmental transitions. Pseudo-transition analysis recapitulates known biology and identifies an unexpectedly sparse, transition-dependent regulatory landscape: typically a handful of regulatory events drive adaptation between carbon sources, with transcription mainly regulating TCA cycle flux and reactants regulating EMP pathway flux. We verify these observations using time-resolved measurements of the diauxic shift, demonstrating that some dynamic transitions can be approximated as monotonic shifts between steady-state extremes. Overall, we show that pseudo-transition analysis can explore the vast regulatory landscape of dynamic transitions using relatively few steady-state data, thereby guiding time-consuming, hypothesis-driven molecular validations.

The purpose of this study was to assess the possible influence of beavers on the contamination of lake water with zoonotic parasites Giardia duodenalis and Cryptosporidium spp., with respect to the risk to human health. A total of 79 water samples were taken around the habitats of beavers from 14 localities situated in the recreational Masurian Lake District (north-eastern Poland). Water was sampled in the spring and autumn seasons, at different distances from beavers’ lodges (0-2, 10, 30, and 50 m). The samples were examined for the presence of (oo)cysts of zoonotic protozoa Giardia duodenalis and Cryptosporidium spp. by direct fluorescence assay (DFA) and by nested and real time PCR. By DFA, the presence of Giardia cysts was found in 36 samples (45.6%) and the presence of Cryptosporidium oocysts in 26 samples (32.9%). Numbers of Giardia cysts, Cryptosporidium oocysts, and summarised (oo)cysts of both parasites showed a significant variation depending on locality. The numbers of Giardia cysts significantly decreased with the distance from beavers’ lodges while the numbers of Cryptosporidium oocysts did not show such dependence. The amount of Giardia cysts in samples collected in spring was approximately 3 times higher than in autumn. Conversely, a larger number of Cryptosporidium oocysts were detected in samples collected in autumn than in spring. By PCR, Giardia DNA was found in 38 samples (48.1%) whereas DNA of Cryptosporidium was found in only 7 samples (8.9%). Eleven Giardia isolates were subjected to phylogenetic analysis by restriction fragment length polymorphism PCR or sequencing which evidenced their belonging to zoonotic assemblages: A (3 isolates) and B (8 isolates). In conclusion, water in the vicinity of beavers’ lodges in the tested region was markedly contaminated with (oo)cysts of Giardia duodenalis and Cryptosporidium spp., which confirms the potential role of beavers as a reservoir of these parasites and indicates a need for implementation of appropriate preventive measures to protect tourists’ health.

The aim of the study was to estimate the current prevalence of E. multilocularis in selected populations of red foxes in Poland and to evaluate the changes in prevalence of this parasite by comparison with the results obtained in the same area during earlier surveillance. The investigations were performed in the area of four Polish provinces: 2 eastern/south-eastern (Lubelskie and Podkarpackie) and 2 south-western (Śląskie and Opolskie). Five hundred red foxes coming from the investigated areas were examined between 2013 and 2014 to estimate the current situation in selected provinces. Moreover, 550 red foxes from the same areas examined between 2007 and 2013 were used for comparison of differences in E. multilocularis prevalences in time. Intestines were examined with the use of the sedimentation and counting technique. Among 500 foxes examined in the current study, 118 were positive for E. multilocularis. There were differences in prevalence between individual provinces: Podkarpackie Province - 54.6%, Lubelskie Province - 18.9%, Śląskie Province - 11.7%, and Opolskie Province - 3.9%. Statistical analysis demonstrated that in most cases there were no differences in prevalence between the current results and the results from previous studies. Only in Opolskie Province was a statistically significant increase observed between 2010 and 2014. A stable degree of infection in the region with high prevalence of this parasite was demonstrated. However, a significant increase in the region with very low prevalence of E. multilocularis points out the necessity to monitor this infection during the coming years to control the progress of the disease

AbstractThe complexity of the hardware and the amount of data collected during the PET imaging process require application of modern methods of efficient data organization and processing. In this article, we will discuss the data structures and the flow of collected data from the novel TOF-PET medical scanner that is being developed at the Jagiellonian University. The developed data format reflects the registration process of the γ quanta emitted from positron electron annihilation, front-end electronic structure, and required input information for the image reconstruction. In addition, the system database fulfills possible demands of the evolving J-PET project.

AbstractA novel PET detector consisting of strips of polymer scintillators is being developed by the Jagiellonian Positron Emission Tomograph (J-PET) collaboration. The map of efficiency and the map of geometrical acceptance of the two-strip J-PET scanner are presented. The map of efficiency was determined using the Monte Carlo simulation software GEANT4 Application for Tomographic Emission (GATE), which is based on GEANT4. Both maps were compared using a method based on the χ2-test.

AbstractWe discuss computing issues for data analysis and image reconstruction of positron emission tomography based on time-of-flight medical scanner or other medical scanning devices producing large volumes of data. Service architecture based on grid and cloud concepts for distributed processing is proposed and critically discussed.

AbstractThis article describes the simulations of the scattering of annihilation γ quanta in a strip of a plastic scintillator. Such strips constitute the basic detection modules in a newly proposed positron emission tomography (PET), which utilizes plastic scintillators instead of inorganic crystals. An algorithm simulating the chain of Compton scatterings was elaborated and a series of simulations have been conducted for the scintillator strip with a cross-section of 5×19 mm. The results indicate that secondary interactions occur only in the case of about 8% of the events and only 25% of these events take place in the distance larger than 0.5 cm from the primary interaction. Also, the light signals produced at the primary and secondary interactions overlap with the delay, the distribution of which is characterized by a full width at half-maximum (FWHM) of about 40 ps.

AbstractA method of the determination of a γ-quantum absorption point in a plastic scintillator block using a matrix of wavelength-shifting (WLS) strips is proposed. An application of this method for the improvement of position resolution in newly proposed positron emission tomography (PET) detectors based on plastic scintillators is presented. The method enables to reduce parallax errors in the reconstruction of images, which occurs in the presently used PET scanners.

AbstractThis paper describes three methods regarding the production of plastic scintillators. One method appears to be suitable for the manufacturing of plastic scintillators, revealing properties which fulfill the requirements of novel positron emission tomography scanners based on plastic scintillators. The key parameters of the manufacturing process are determined and discussed.

AbstractThis article is focused on data acquisition system (DAQ) designed especially to be used in positron emission tomography (PET) or single-photon emission computed tomography. The system allows for continuous registration of analog signals during measurement. It has been designed to optimize registration and processing of the information carried by signals from the detector system in PET scanner. The processing does not require any rejection of data with a trigger system. The proposed system possesses also an ability to implement various data analysis algorithms that can be performed in real time during data collection.

AbstractPhotomultipliers are commonly used in commercial PET scanner as devices that convert light produced in scintillator by gamma quanta from positron-electron annihilation into electrical signal. For proper analysis of obtained electrical signal, a photomultiplier gain curve must be known, since gain can be significantly different even between photomultipliers of the same model. In this article, we describe single photoelectron method used for photomultiplier calibration applied for J-PET scanner, a novel PET detector being developed at Jagiellonian University. A description of calibration method, an example of calibration curve, and a gain of few Hamamatsu R4998 photomultipliers are presented.

AbstractUsing a theory of list-mode maximum likelihood expectation-maximization (MLEM) algorithm, in this contribution, we present a derivation of the system response kernel for a novel positron emission tomography (PET) detector based on plastic scintillators.

AbstractNovel time-of-flight positron emission tomography (TOF-PET) scanner solutions demand, apart from the state-of-the-art detectors, software for fast processing of the gathered data, monitoring of the whole scanner, and reconstruction of the PET image. In this article, we present an analysis framework for the novel STRIP-PET scanner developed by the J-PET collaboration in the Institute of Physics of the Jagiellonian University. This software is based on the ROOT package used in many particle physics experiments.

AbstractA positron emission tomography (PET) scan does not measure an image directly. Instead, a PET scan measures a sinogram at the boundary of the field-of-view that consists of measurements of the sums of all the counts along the lines connecting the two detectors. Because there is a multitude of detectors built in a typical PET structure, there are many possible detector pairs that pertain to the measurement. The problem is how to turn this measurement into an image (this is called imaging). Significant improvement in PET image quality was achieved with the introduction of iterative reconstruction techniques. This was realized approximately 20 years ago (with the advent of new powerful computing processors). However, three-dimensional imaging still remains a challenge. The purpose of the image reconstruction algorithm is to process this imperfect count data for a large number (many millions) of lines of response and millions of detected photons to produce an image showing the distribution of the labeled molecules in space.

AbstractAll of the present methods for calibration and monitoring of time-of-flight positron emission tomography (TOF-PET) scanner detectors utilize radioactive isotopes, such as 22Na or 68Ge, which are placed or rotate inside the scanner. In this article, we describe a novel method based on the cosmic rays application to the PET calibration and monitoring methods. The concept allows to overcome many of the drawbacks of the present methods and it is well suited for newly developed TOF-PET scanners with a large longitudinal field of view. The method enables also the monitoring of the quality of the scintillator materials and in general allows for the continuous quality assurance of the PET detector performance.

AbstractThis article presents an application of a novel technique for precise measurements of time and charge based solely on a field programmable gate array (FPGA) device for positron emission tomography (PET). The described approach simplifies electronic circuits, reduces the power consumption, lowers costs, merges front-end electronics with digital electronics, and also makes more compact final design. Furthermore, it allows to measure time when analog signals cross a reference voltage at different threshold levels with a very high precision of ~15 ps (rms) and thus enables sampling of signals in a voltage domain.

OBJECTIVES To prospectively determine the incidence of venous thromboembolism (VTE) following major head and neck surgery. At the midpoint of enrollment, an interim analysis was performed to determine if it was ethical to continue this study as an observational study without routine anticoagulation. DESIGN Prospective, observational cohort study. SETTING Academic surgical center. PATIENTS The interim analysis comprised 47 subjects. MAIN OUTCOME MEASURE The total number of new cases of VTE (superficial and deep) identified within 30 days of surgery and confirmed on diagnostic imaging. These cases were further categorized as clinically relevant and nonclinically relevant. Clinically relevant VTEs were those requiring more than 6 weeks of anticoagulation or were associated with any negative impact on clinical course. On postoperative day 2 or 3, subjects were clinically examined and received duplex ultrasonography. Subjects with negative findings from examination and ultrasonography were followed up clinically; subjects with evidence of deep venous thrombus or pulmonary embolism were given therapeutic anticoagulation. Subjects with superficial VTE received repeated ultrasonography on postoperative days 4 to 6. Subjects were monitored for 30 days after surgery. RESULTS Three subjects (6%) were identified as having clinically significant VTE: 2 cases of deep venous thrombus and 1 case of pulmonary embolism. Two additional subjects had lower extremity superficial VTE without clinical findings, which were detected by ultrasonography alone. No statistically significant differences were seen between patients with VTE and those without VTE. CONCLUSIONS This interim analysis of the first prospective study of the incidence of VTE in patients with head and neck cancer showed a VTE rate slightly higher than previously estimated in retrospective studies. There have been no unexpected serious adverse events and no rationale for early termination of the study.

Faced with high levels of senior civil servant retirement in the coming years and limited by civil service requirements, government organizations often struggle to maintain the knowledge base of previous processes and results while promoting people who are truly interested in being leaders in an agency. Upcoming generations of public sector workers do not share the same motivation and workplace characteristics of current exiting civil servants, further complicating smooth transitions of leadership. Government personnel systems for the most part are inflexible and slow to hire, and retention methods for workers do not encourage succession planning. Against this backdrop, a five-phased human capital management system, using some of the best practices found in both public and private sector organizations, is proposed as a solution for replacing government retirees with workers who are prepared for their leadership and management roles.

For the analysis of enzyme kinetics, a variety of programs exists. These programs apply either algebraic or dynamic parameter estimation, requiring different approaches for data fitting. The choice of approach and computer program is usually subjective, and it is generally assumed that this choice has no influence on the obtained parameter estimates. However, this assumption has not yet been verified comprehensively. Therefore, in this study, five computer programs for progress curve analysis were compared with respect to accuracy and minimum data amount required to obtain accurate parameter estimates. While two of these five computer programs (MS‐Excel, Origin) use algebraic parameter estimation, three computer programs (Encora, ModelMaker, gPROMS) are able to perform dynamic parameter estimation. For this comparison, the industrially important enzyme penicillin amidase (EC 3.5.1.11) was studied, and both experimental and in silicodata were used. It was shown that significant differences in the estimated parameter values arise by using different computer programs, especially if the number of data points is low. Therefore, deviations between parameter values reported in the literature could simply be caused by the use of different computer programs.

Background— A number of medications such as beta-blockers, ACE-inhibitors, angiotensin receptor blockers and aldosterone antagonists, improve survival in patients with heart failure (HF) and reduced ejection fraction. No therapy has been proved to be beneficial for patients with heart failure and preserved ejection fraction (PLVEF).Objectives— The aim of the study was to assess the effect of statin therapy on all-cause mortality and cardiovascular rehospitalization rate in patients with HF and PLVEF during one-year follow-up.Methods— We evaluated 146 patients with HF and PLVEF (ejection fraction ≥ 45%). Patients were divided into the statin therapy group (n = 103, mean age 69 ± 11 y, 52 men) and the group without statins (n = 43, mean age 66 ± 16 y, 25 men).We analysed the effects of the statin treatment prescribed to patients at discharge. Patients were followed up for one year.Results— The age, gender, NYHA functional class, prevalence of co-morbidities (renal dysfunction, COPD, diabetes mellitus) did not differ between the groups (P= NS). Patients receiving statin therapy more frequently had an ischaemic aetiology of HF (79% vs. 39.5%; P< 0.001) and hypertension (76% vs. 58%; P< 0.05). No differences in ejection fraction were observed neither by echocardiography (58% vs. 55%; P= NS) nor by basic laboratory data. Patients who received statins were often additionally treated with beta-blockers (91% vs. 70%; P< 0.005), aspirin (77 vs. 44%; P< 0.01), thienopyridines (22% vs. 5%; P< 0.01) and less frequently with oral anticoagulants (5% vs. 23%; P< 0.005). In the group receiving statins a significantly lower mortality (4% vs. 21%; P< 0.001) and rehospitalization rate (43% vs. 69%; P< 0.05) was documented. After adjustment for all univariate predictors of the occurrence of study primary end-points, statin therapy was shown to be associated with significant and independent reduction in all-cause mortality (HR = 0.24 [95%CI: 0.07 – 0.90] P< 0.05) and cardiovascular rehospitalization rate (HR = 0.55 [95%CI: 0.33 – 0.92] P< 0.05). After propensity matching statin therapy remained an independent factor reducing one-year mortality rate (HR = 0.11 [95%CI: 0.01 – 0.99] P< 0.05].Conclusions— This study showed that statin therapy may have beneficial effects on mortality and rehospitalization rates among patients with HF and PLVEF. It also suggests a potential role for statins as a new therapeutic option in patients with HF and PLVEF, but these observations need to be confirmed in large randomized trials.

Human parvovirus B19 infections are common in the general population, and infection during pregnancy may cause hydrops fetalisand fetal death. To initiate adequate treatment, accurate laboratory diagnosis is essential. The most sensitive tests are nested PCR systems, but these assays provide semiquantitative results at best. A parvovirus B19 DNA assay was developed based on the real time TaqMan PCR. This method was calibrated on the basis of serial plasmid dilutions and tested with an international parvovirus B19 standard. The assay was capable of quantifying parvovirus B19 DNA from one to about 5 × 107genome equivalents per reaction (corresponding to 100 to 5 × 109genome equivalents per ml serum). Samples from 51 pregnant women with suspected acute parvovirus B19 infection were tested, and positive PCR results were obtained in at least one of the materials investigated in 41 cases. The median viral DNA load in maternal blood samples was 1.3 × 104copies/ml (range 7.2 × 102–2.6 × 107). Maternal virus DNA concentration was not associated with the presence of maternal symptoms and/or fetal complications. As the stage of infection was not known in the majority of cases, our data do not exclude an association between peak levels of parvovirus B19 DNA and the development of complications. Maternal sera and corresponding fetal material were available for concurrent testing from 15 DNA‐positive cases: in most fetal samples, viral DNA concentrations were several orders of magnitude higher (up to 2.1 × 1012copies/ml) compared to the corresponding maternal blood samples. J. Med. Virol. 67:259–266, 2002. © 2002 Wiley‐Liss, Inc.

The attempt was made to prepare an ionene like base by reacting diethylamine (DEA) with glycidol (Gly). It turned out that the reaction proceeds via two steps witch differ significantly. When the rate of added DEA to Gly in bulk becomes 1 : 13 the temperature jumps up suddenly. The product proved to be a water soluble oligomer having a molecular weight of Mn> 465 g/mol, a nitrogen content of 1.06%, and pH 9.5. Based on the 13C NMR and IR spectra, schemes of polyreactions were proposed according to which amine groups containing moieties of low molecular weight are formed. These subsequently function as initiators of Gly homopolymerization according to a chain mechanism.

ABSTRACTWe recovered two isolates (EP1 and EP2) of Escherichia colifrom the same patient that had identical pulsed-field gel electrophoresis patterns but required different MICs of ciprofloxacin (CIP): 16 and 256 mg/liter for EP1 and EP2, respectively. Both isolates had mutations in the quinolone resistance-determining regions of GyrA (Ser83Leu and Asp87Tyr) and ParC (Ser80Ile), but not in those regions of GyrB or ParE. Isolate EP2 was also more resistant to chloramphenicol, tetracyclines, cefuroxime, and organic solvents. A deletion of adenine (A) 1821 was found in marRof isolate EP2, which resulted in an 18-amino-acid C-terminal deletion in the MarR protein. The causative relationship between ΔA1821 and the Mar phenotype was demonstrated both by the replacement of the wild-typemarRby marRΔA1821 in isolate EP1 and by complementation with the wild-type marRintransin isolate EP2. In isolate EP2 complemented with wild-type marR, susceptibility to chloramphenicol was restored completely, whereas susceptibility to CIP was restored only incompletely. Northern blotting demonstrated increased expression ofmarAand acrABbut not of soxSin isolate EP2 compared to EP1. In conclusion, the deletion of A1821 inmarRin the clinical isolate EP2 caused an increase in the MICs of CIP and unrelated antibiotics. Presumably, the C-terminal part of MarR is necessary for proper repressor function.