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Funding Acknowledgements Type of funding sources: Public hospital(s). Main funding source(s): The study was supported by an intramural research grant from the National Institute of Cardiology. Background Heart failure (HF) is a significant cause of morbidity and mortality in both women and men. The discrepancies in the underlying mechanisms and etiology of HF in both sexes suggest that factors related to the prognosis of HF and the risk of death may also be different in men and women. Objective The aim of the study was to identify factors related with survival in men and women with HF. Methods Patients from a hospital database coded as hospitalizations for HF between 01/2014 and 05/2019 were included in the analysis. In all patients, the diagnosis of HF was verified. Information on HF, comorbidities, and death was obtained from available medical records. Kaplan-Meier survival curves were generated to analyze time-to-event data and to compare survival in both men and women. Multivariable Cox proportional hazard analysis was used to evaluate the risk of death and related factors. Results 1824 (70.1%) men and 777 (29.9%) women were included. Women were older than men (68.3 vs. 62.4 years; p The results of the multivariable Cox proportional hazards analysis are presented in Table 1. In both men and women respectively, after adjustment for other covariates, a significant association with an increased risk of death was documented for: catecholamines (HR=2.27 and HR=2.92), significant tricuspid regurgitation (HR=1.46 and HR=1.66), renal failure (HR=1.59 and HR=1.68), liver failure (HR=1.90 and HR=2.44), anemia (HR=1.51 and HR=1.46) and emergency admission (HR=1.21 and HR=1.77). The optimal dose of ACEI was associated with a decreased risk of death in both sexes (HR=0.75 in men and HR=0.60 in women). In men, we also found that other factors, such as diuretics (HR=2.29), chronic HF (HR=1.87), ischemic etiology (HR=1.40), atherosclerosis (HR=1.37), stroke (HR = 1.28), cardioverter defibrillator implantation (HR=1.27), ventricular arrythmias (HR=1.24), and age (HR=1.02) were related with a higher risk of death. Furthermore, only in women a higher risk of death was associated with dementia (HR=2.26), hypertension (HR=1.81), amiodarone (HR=1.68), aortic stenosis (HR=1.52), and myocardial infarction (HR=1.46), while a lower risk was found for an increasing number of comorbidities (HR=0.86). Conclusions Overall survival in men and women with HF was similar, as well as the strength and direction of the relationship with the risk of death in common risk factors. However, some of the predictors of death differed between men and women, which should draw our attention to potential differences in gender-related parameters affecting survival in HF.

Background The novel method of comprehensive rehabilitation after left ventricular assist device (LVAD) implantation was developed in our institution. Cardiopulmonary exercise test was used to program the training and to assess the results of rehabilitation. Study group 47 consecutive LVAD (32 Heart Mate III, 15 HeartWare) recipients (19–68 years, mean 58.7 years, 43 men) participated in the rehabilitation program. Proposed 4–5 week program included supervised endurance training on cycloergometer (5 times per week), resistance training, general fitness exercises with elements of equivalent and coordination exercises (every day). It was followed by individual exercises performed at home. 6-minute walk test (6MWT), cardiopulmonary exercise test (CPET) and prognostic biomarkers of heart failure: NT-proBNP, Galectin-3 and ST2 were investigated at the beginning and at the end of rehabilitation program. Results See Table 1. Increase of 6MWT distance, higher maximal workload, peak VO2 and upward shift of anaerobic threshold (AT) in CPET were observed in all patients. Significant reductions of NTproBNP, ST2 and galectin-3 levels were observed. There were no major adverse events during rehabilitation. Conclusions Comprehensive novel rehabilitation in LVAD recipients is safe and results in significant improvement of functional tests and biomarkers of heart failure. Funding Acknowledgement Type of funding sources: Public grant(s) – National budget only. Main funding source(s): National Centre for Research and Development

Background Left ventricular assist devices (LVAD) are increasingly implanted in patients with end-stage heart failure. Patients require special care in terms of the safety and effectiveness of therapy, but during pandemic lockdown it is much more difficult to achieve. For many years at our institution, apart from routine personal visits, we have been using the REMEDIZER® internet communicator for remote care in LVAD group of patients. Objective - evaluation of the safety and effectiveness of remote monitoring in the care of patients with LVAD during the COVID pandemic – evaluation of the safety of remote monitoring with a designated communicator instead of personal visits Methods During the lockdown period (01/03/2020 - 31/12/2020), 72 patients (3 female) pts mean age 54.7±12,1 years with LVAD were monitored. For epidemiological reasons, the number of personal visits has been reduced in favor of telephone consultations and an increased volume of data entered into the REMEDIZER® internet communicator. The data collected in this period were compared with the data collected on 1 March 2019 - 31 December 2019, when: 53 pts (1 female) mean age 56,2±11,78 years were routinely, personally controlled at the Center for at least every 3 months and had blood, echo and LVAD examinations. Patients entered pump parameters: flow, motor speed, power consumption, pulse and blood pressure, body weight and temperature, at least twice a day (morning and evening) INR and dose of warfarin used were also reported. The number of complications during LVAD support was assessed: death or heart transplantation major complications: stroke, hemorrhage, pump thrombosis also other like arrhythmias requiring ICD intervention, hospitalization. Results Mean time of monitoring from hospital discharge after LVAD implantation to the end of observation in 2020 cohort was 651±486 days compared to 586±508, days in 2019 cohort In 2019, personal visits were performed significantly more often, 94 v. 17 (p In 2020, 5 patients (6,94%) died compared with 4 (7,55%) in 2019 (NS). In 2020, 9 patients (12,5%) were transplanted v. 3 (5,66%) in 2019. We observed 22 episodes of major complications in the 2020 cohort vs 20 in 2019 (NS); 11 ICD interventions vs 13 in 2019 (NS). Conclusions Replacing routine personal visits with increased patient self-control and constant remote contact with the center allowed a safe organization of patient care during COVID-19 pandemic The use of REMEDIZER® internet communicator dedicated for LVAD patients for remote care control proved to be effective and safe to control LVAD patients. Funding Acknowledgement Type of funding sources: Public grant(s) – National budget only. Main funding source(s): The study is funded by the National Center for Research and Development, Poland

High resolution, high accuracy mass spectrometry is widely used to characterise environmental or biological samples with highly complex composition enabling the identification of chemical composition of often unknown compounds. Despite instrumental advancements, the accurate molecular assignment of compounds acquired in high resolution mass spectra remains time consuming and requires automated algorithms, especially for samples covering a wide mass range and large numbers of compounds. A new processing scheme is introduced implementing filtering methods based on element assignment, instrumental error, and blank subtraction. Optional post-processing incorporates common ion selection across replicate measurements and shoulder ion removal. The scheme allows both positive and negative direct infusion electrospray ionisation (ESI) and atmospheric pressure photoionisation (APPI) acquisition with the same programs. An example application to atmospheric organic aerosol samples using an Orbitrap mass spectrometer is reported for both ionisation techniques resulting in final spectra with 0.8% and 8.4% of the peaks retained from the raw spectra for APPI positive and ESI negative acquisition, respectively.

The spatial sensitivity of bulk acoustic mode resonators can influence calibrations when they are implemented as accurate mass sensors of surface-bound particles. A new spatial sensitivity model based on images of the resonator surface is introduced from early principles. The adsorption of particles was studied empirically by repeatedly drying particle laden droplets on the surface of two 3.14 MHz bulk acoustic mode resonators. Theoretical and experimental results were compared to identify three scenarios over the course of consecutive droplet evaporation with varying spatial sensitivity influences. Examining different surface treatments for the resonators revealed the hydrophilic surface to have a higher rate of particle stacking and conglomeration

The interaction between atmospheric aerosol particles and water vapor influences aerosol size, phase, and composition, parameters which critically influence their impacts in the atmosphere. Methods to accurately measure aerosol water uptake for a wide range of particle types are therefore merited. We present here a new method for characterizing aerosol hygroscopicity, an impaction stage containing a microelectromechanical systems (MEMS) microresonator. We find that deliquescence and efflorescence relative humidities (RHs) of sodium chloride and ammonium sulfate are easily diagnosed via changes in resonant frequency and peak sharpness. These agree well with literature values and thermodynamic models. Furthermore, we demonstrate that, unlike other resonator-based techniques, full hygroscopic growth curves can be derived, including for an inorganic-organic mixture (sodium chloride and malonic acid) which remains liquid at all RHs. The response of the microresonator frequency to temperature and particle mechanical properties and the resulting limitations when measuring hygroscopicity are discussed. MEMS resonators show great potential as miniaturized ambient aerosol mass monitors, and future work will consider the applicability of our approach to complex ambient samples. The technique also offers an alternative to established methods for accurate thermodynamic measurements in the laboratory.

Aerosol mass measurements are a key air pollution parameter that is regulated in most countries. Beyond mass measurements, the precise composition of the aerosol is essential in identifying sources and impacts on health and climate. The conventional method for simultaneously quantifying mass and composition is to collect aerosol onto filter or impactor samples followed by laboratory analysis. This approach requires long collection times – providing poor time resolution for mass measurements – and long sample preparation prior to analysis. The first limitation can be circumvented with microresonators, which are novel particulate mass sensors with high mass sensitivities and time resolutions. In addition, direct surface analysis techniques, like liquid extraction surface analysis mass spectrometry (LESA-MS), shorten sample preparation times. This work combines, for the first time, the high time resolution mass measurements of a microresonator with the integrated compositional analysis of LESA-MS. Laboratory-produced secondary organic aerosol were collected onto a microresonator via impaction with LESA-MS being used to analyse the chemical composition afterwards. The results were compared with classic filter extraction methods and literature with the final spectra matching the expected reaction products. The combined technique demonstrates an extension to current microresonator applications and illustrates their potential for ambient aerosol studies.

Background The long-term survival of 209 consecutive patients (mean age, 46 ± 15 years) from a single center with ≥1 diagnostic myocardial biopsy after heart transplantation was analyzed. Methods Patients were considered as C4d positive if a capillary staining (immunohistochemistry in paraffin samples) was observed in ≥1 myocardial biopsy. Data were analyzed according to pathologic consensus of antibody mediated rejection definition of C4d+ positivity: 2004 definition in group A and the 2013 definition in group B and compared with their respective controls, composed of patients who do not meet those criteria. Age, follow-up time, and number of biopsies were comparable between patients with C4d+ and controls in both groups. Follow-up was 100% complete with mean of observation time 2143 days. Results During the follow-up period, 62 patients died (group A: C4d+ 32% vs controls 29%; group B: C4d+ 36% vs controls 29% [ P = NS]). There were no differences in survival between patients with positive staining and without C4d+ staining when Kaplan-Meier survival curves were compared. Conclusions The presence of C4d positive staining in myocardial capillaries of heart biopsies of patients after heart transplantation, as an isolated finding, was not related to worse long-term survival.

Aerosol-cloud interaction contributes to the largest uncertainties in the estimation and interpretation of the Earth's changing energy budget. The present study explores experimentally the impacts of water condensation-evaporation events, mimicking processes occurring, in atmospheric clouds, on the molecular composition of secondary organic aerosol (SOA) from the photooxidation of methacrolein. A range of on and off-line mass spectrometry techniques were used to obtain a detailed chemical characterization of SOA formed in control experiments in dry conditions, in triphasic experiments simulating gas-particle-cloud droplet interactions (starting from dry conditions and from 60% relative humidity (RH)), and in bulk aqueous-phase experiments. We observed that cloud events trigger fast SOA formation accompanied by evaporative losses. These evaporative losses decreased SOA concentration in the simulation chamber by 25-32% upon RH increase, while aqueous SOA was found to be metastable and slowly evaporated after cloud dissipation. In the simulation chamber, SOA composition measured with a high-resolution time-of flight aerosol mass spectrometer, did not change during cloud events compared with high RH conditions (RH > 80%). In all experiments, off-line mass spectrometry techniques emphasize the critical role of 2-methylglyceric acid as a major product of isoprene chemistry, as an important contributor to the total SOA mass (15-20%) and as a key building block of oligomers found in the particulate phase. Interestingly, the comparison between the series of oligomers obtained from experiments performed under different conditions show a markedly different reactivity. In particular, long reaction times at high RH seem to create the conditions for aqueous-phase processing to occur in a more efficient manner than during two relatively short cloud events.

The cleaning of a collection-based sensor extends its lifetime and reduces its effective cost. Existing cleaning regimes for silicon-based devices typically require access to large laboratory equipment. A simple cleaning method based on solvent rinses is presented here for the application of microresonator atmospheric particulate mass sensors. The suggested approach is intended for scenarios with limited access to laboratory equipment. Two piezoelectric resonator topologies (in-plane bulk mode and out-of-plane flexural) collected particles via impaction for an hour before rinsing. The solvent rinses reset the resonant frequency and quality factor of each resonator to within 0.4% and 10% of their original values, respectively. Subsequent mass collections were largely repeatable despite fluctuations in particle concentration and deposition location. The presented method provides a straightforward but effective cleaning method for soluble particulate removal. A physical cleaning method is required after substantial insoluble particle adsorption.

© 2016 IEEE.Current portable particle detection instruments typically rely on optical methods which are limited to 100 nm diameter particles. Microfabricated bulk acoustic resonators, when used as mass balances, could take particle detection below this limit. This study examines the collection of particles onto piezoelectric bulk acoustic mode resonators from gaseous flow using classical impaction. Collection of both polystyrene latex particles and α-pinene secondary organic aerosol particles was examined in terms of frequency shift and collection efficiency. A new experimental setup was introduced which allows for adjusting major impactor, resonator, and aerosol properties. Preliminary results show the setup works for both particles while the saturation limit was not reached within an hour despite highly elevated particle concentrations.

Neutrinos are copiously emitted from black hole accretion disks playing a fundamental role in their evolution, as well as in the production of gamma ray bursts and r-process nucleosynthesis. The black hole generates a strong gravitational field able to change the properties of the emerging neutrinos. We study the influence of the black hole spin on the structure of the neutrino surfaces, neutrino luminosities, average neutrino energies, and event counts at SuperK. We consider several disk models and provide estimates that cover different black hole efficiency scenarios. We discuss the influence of the detector's inclination with respect to the axis of the torus on neutrino properties. We find that tori around spinning black holes have larger luminosities, energies and rates compared to tori around static black holes, and that the inclination of the observer causes a reduction in the luminosities and detection rates but an increase in the average energies., 10 pages, 5 figures, submitted to PRD

The paper presents the carbon black production by plasma method and the thermal–mechanical and oxidation induction time tests of LDPE and HDPE modified by changeable content of plasma carbon from 0.1 to 1.0% w/w. The investigations were based on SEM images, microscope images and XRD studies. Properties of plasma carbon black were measured by physical and chemical tests like BET adsorption, IA and DBF numbers, etc. The results of ageing tests showed the increased oxidation induction time, 57 min, for 0.5% w/w of plasma carbon black content in the composition.

Microfabricated in-plane bulk acoustic resonators can be configured as gravimetric sensors wherein the mass of surface-bound species is transduced as a shift in the resonant frequency. Using this principle, we examine the adsorption of spherical polystyrene latex particles on the resonator surface by drying particulate laden droplets. Distribution of particles on the surface is governed by the coffee-ring effect which is correlated to the observed frequency response of the resonators. We also present an analytical approach to describe the spatial dependence of adsorbed mass on the induced frequency shift for square plate resonators which can be extended to model other resonator geometries.

The Arctic onshore environment contains regions of discontinuous permafrost, where pipes may be subject to displacement-controlled bending in addition to high hoop stresses due to the pressurized fluids being transported. Considering the displacement-controlled nature of the deformations, strain-based design methodologies have been developed for permafrost pipelines when they are subject to bending and tension, which limit the longitudinal compressive and tensile strains. The widely accepted methodology in the industry to obtain the compressive strain capacity of line pipes subject to bending is to conduct Finite Element Analysis, incorporating material and geometrical nonlinearity calibrated against benchmark full-scale tests (bend tests) [1,2]. During these tests, compressive strains can be measured by various methods. The seemingly obvious choice is to apply strain gauges along the compression face of the specimen with respect to bending (intrados). This method will provide reasonable results until the compressive strain pattern begins to vary due to the initiation of buckle formation, which typically occurs shortly after yield. In order to measure average compressive strain beyond yield and up to buckling, the method used by C-FER Technologies (C-FER) involves using rotation measurement devices (inclinometers) to calculate the strain change between the most compressive and tensile fibres of the specimen (intrados and extrados, respectively) with respect to the bending direction. This value is then subtracted from the tensile strain gauge readings as measured by the strain gauge(s) located on the extrados of the specimen. The average compressive strain values derived from the inclinometer and extrados strain gauge measurements are based on the assumption that the plane sections remain plane. Recently, five large diameter pipes were bend-tested at C-FER’s testing facility in Edmonton, Alberta. In addition to the compressive strain measurement method used by C-FER described above (C-FER method), a visual image correlation (VIC) camera system was used to survey the strain distribution on the compressive face of the specimens. This paper gives a brief description of the test setup and instrumentation of this test program. The VIC camera setup and measurement technique are described and the overall strain distribution on the bending intrados as measured by the VIC cameras is presented. Strain measured by the VIC system is compared with gauge measurements at local points as well as the average compressive strain behaviour of the specimens obtained through the C-FER method described above. The results show that the VIC system can be a candidate to replace the conventional measurement techniques employed for compressive strain limit testing in support of strain-based design of arctic pipelines.

OBJECTIVE The aim of this study was to compare health behaviors among patients after heart transplantation, depending on the mode of qualification for the surgery. PATIENTS AND METHODS A questionnaire was completed by 115 patients who underwent heart transplantation surgery. The first part covered sociodemographic data before and after transplantation; the second part the medical data, and the last part behaviors before and after transplantation, such as smoking tobacco, drinking alcohol, and systematic compliance to medications. Behaviors associated with health were evaluated with the of a health behavior inventory including 24 statements referring to behaviors associated with health. RESULTS Fifty-two patients (45.21%) including 13 women and 39 men underwent a heart transplantation performed in the "urgent" mode. They were significantly younger than those with a "planned" transplantation: 50.65±16.19 vs 57.22±10.26 (P

In this paper the problem of time domain equalizer (TEQ) design for discrete-multitone (DMT) transmission system is analyzed. The proposed algorithm uses combined objective of line impulse response shortening and frequency shaping (weighting) of signal and noise before demodulation. Suboptimal shaping, being simple noise whitening, is shown to compensate FFT noise spreading. The resulting design algorithm defines the desirable impulse response both outside and inside a target window. The equalizer taps are evaluated by linear weighted least squares fit. Achievable levels of SNR and capacity outperform simpler shortening algorithms and approach matched filter bound. They also behave stably with an increase of TEQ length.

The demonstration of patient case reports in the course of a clinical round is an essential part of teaching medicine and dentistry. However, suitable live patients with particular problems are not always available at a time when teaching is taking place. This project therefore had the objective of establishing a web-based, virtual e-learning concept for demonstrating case reports independent of time and place, with the possibility of an interactive examination, diagnosis, and interdisciplinary therapy decision making for medical and dental students. Anonymized case reports of diseases in the oral and maxillofacial region and the interdisciplinary treatment were digitized and prepared in a web-based format. The technical aspect was based on connecting flash modules with videos and animation, and monitoring through HTML and Javascript. Due to the modular concept and the programming used, the learning environment was independent of platform and open. Independent formats (.swf, .avi, .mpeg, etc.) were integrated into the individual modules. According to a hierarchic decision system, the user was guided interactively to the diagnosis through a differential diagnostic exclusion process. Sound was digitized and integrated in mp3 compressed form in the 3D models for lip-synchronous speech output. The speech output was connected with a virtual 3D tutor that acted in an advisory capacity in reaching a diagnosis and determining therapy. Further sources of information and literature with abstracts or pdf files of the subject-related publications were inserted to ensure that the teaching was objective. To conclude the virtual clinical round, a check on learning success was conducted in the form of a multimedia multiple choice test.

Purpose The number of pts on waiting list for OHT still exceeds the number of available organs and mostly UNOS 1 status pts are transplanted. The purpose of the study was to determine which factors increased the risk of death of patients fulfilling UNOS 2 criteria when listed for OHT. Methods and Materials Study cohort included 307 pts (289 men), mean age 51 ± 8 out of 632 pts on waiting list for HTX during the period 12.2003 - 01.2007 wth initial status UNOS 2 and who were not transplanted until 2008. Clinical and biochemical data were collected at the time of listing Cox multivariate proportional hazard model was used to determine factors influencing survival. For significant variables in Cox analysis stratified by terciles Kaplan_Meier curves and log rank test were designed to analyse survival. Results During follow up (median observation time 456 days) 82 patients initially qualified for OHT died. From 13 variables included in Cox proportional hazard model only NTproBNP and left ventricular diastolic diameter (LVEDD) were found to be significant predictors of death for UNOS 2 status patients. On Kaplan Meier curves pts with NTproBNP in the highest tercile (>4700 pg/ml) (p=0.0064) have had a poorest and pts in the lowest tercile of LVEDD ( figure 1 ] [ figure 2 ] Conclusions Patients with UNOS 2 status with high NTproBNP and larger LVEDD are at. increased risk of death.

Description of activities of Lieutenant-Colonel Tomasz Zieliński who was not a physician, but being an officer of the Russian army during the Turkish campaign in 1831, had acquainted himself with methods of fighting against cholera and he used them with quite a good result in Osieciny in 1852.

A 30-year old man underwent a head-on motor accident and was admitted to hospital, where he was successfully treated for several injuries. He was discharged home with slight tricuspid regurgitation, without signs of hemodynamic decompensation, and required no further treatment. Five years later he was admitted to the National Institute of Cardiology due to overt right ventricular failure secondary to tricuspid valve regurgitation. After several unsuccessful attempts at papillary muscle and chordal repair, a 33-mm SJM Biocor valve was implanted. This case history underlines the value of echocardiography, even after blunt chest trauma without cardiac symptoms. A good functional result can be achieved years after onset of traumatic valve insufficiency, but early diagnosis and surgical treatment increases the feasibility of tricuspid valve repair rather than replacement, and also prevents progressive deterioration of right ventricular function.

Autovaccines are bacterial preparations derived from non pathogenic autologous bacteria of human origin. In the course of microbiological therapy these individual bacterial vaccines are mainly used in conditions of chronic inflammatory disorders of the respiratory or gastrointestinal tract as well as allergic diseases. Being autologous bacterial preparations from the patients own flora the control of batch variabilities of these individual products represents a special challenge for the manufacturer. A flow cytometric method suitable for batch control of autovaccines is described. The method is based upon the determination of the de novo expression of the CD69 antigen on different leucocyte subpopulations in whole blood cultures after preincubation of cells with different batches of autovaccines. Thus, manufacturers of autovaccines and other microbial preparations are able to reliably control batch variability and immunological activity of such products in accordance with drug regulations. The results of this study highlight the pharmaceutical quality of the individual therapeutic agent autovaccine.

Objective: Mitral valve repair improves symptoms and reduces myocardial remodeling, however in patients with significantly impaired left ventricle systolic function its impact on long term prognosis remains controversial. The aim of the study was to determine the predictors of long term survival in patients with concomitant systolic heart failure and mitral insufficiency undergoing mitral valve repair. Patients and methods: We included 39 patients (aged 63±12 years, 12 women) with LVEF≤40% (mean 32.3±5.7%, ranged: 15-40%) undergoing mitral valve repair. Patients scheduled for concomitant aortic valve surgery, surgical ventricle restoration or operation due to infective endocarditis were excluded from the analysis. Most patients (n=31, 79%) were significantly symptomatic (NYHA class III or IV), although only one required inotropic support as well as IABP before surgery. In 26 cases (67%) mitral insufficiency had an ischemic etiology. Predicted 30-days mortality as estimated by EuroSCORE II or STS risk models was 3.25 and 4.85% (median), respectively. All patients underwent mitral valve repair (restrictive annuloplasty was done in all cases and an additional intervention on mitral valve, e.g. chordal transfer, posterior leaflet quadrangular resection in 6 cases). Moreover, 18 patients underwent coronary artery bypass grafting, 9 - tricuspidal valve repair and 3 - surgical ablation of atrial arrhythmia. 34 demographic, clinical and echocardiographic parameters were analyzed to identify the independent risk factors for late mortality. Results: During median 3.3 years (IQR: 2-5 years) of follow up 13 patients died. There was one intrahospital death (30-days mortality was 2.5%). The 2- and 5- years cumulative survival was 77 and 66%. Multivariate Cox analysis revealed that the independent predictors for death was COPD (HR 7.95, 95% CI 6.66-9.25) and the need of intense postoperative inotropic support (at least two inotropes for at least 48 hours; HR 7.76, 95% CI 6.52-9.0). Surprisingly, according to the univariate analysis, none of the parameters analyzed (including i.e. left ventricle diameter, renal function, concomitant surgical procedure) except for the mentioned above and the length of stay at the ICU (which in fact is strongly correlated with the postoperative heart failure) differed between survivors and non-survivors. Conclusions: Severe postoperative heart failure that could represent poor reserve of impaired left ventricle predicted worse long term prognosis after mitral valve repair. COPD increased late mortality independently of pulmonary hypertension.

Significant pulmonary hypertension in aortic stenosis is evidence of severe dysfunction of the left ventricle. It is also a predictor of a bad prognosis in the natural course of the disease. This study was performed to evaluate the changes in the hemodynamic parameters of pulmonary circulation at rest and effort in patients who had significant pulmonary hypertension preoperatively and underwent valve replacement.The study consists of 11 male patients with aortic stenosis with an average peak transvalvular gradient of 68 mmHg and impaired left ventricular function (mean ejection fraction 38%). Six patients were in NYHA functional class III, and five were in class IV. The patients underwent Swan-Ganz catheterization before urgent valve replacement.Significant pulmonary hypertension was found in all subjects, and a below normal cardiac index in eight. Urgent valve replacement was performed in all patients: two of them were operated on during pulmonary edema and cardiogenic shock which developed soon after diagnosis-one of them died. Patients were followed up six months after surgery, and all of them showed major clinical improvement (six in NYHA class I, four in class II). Mean pulmonary artery systolic pressure dropped from 77 mmHg preoperatively to 32 mmHg, and the pulmonary artery mean pressure from 47 mmHg to 17 mmHg, pulmonary wedge pressure from 32 mmHg to 9 mmHg, and pulmonary vascular resistance from 4.74 to 1.8 Wood units. The cardiac index came back to normal in all patients (2.18 vs. 3.0 l/min/m2). Swan-Ganz catheterization was also performed during exercise (work load; 50 Watts in three patients, 100 Watts in six patients). The reaction of the hemodynamic parameters on exercise in most patients was almost normal.Our data indicate that in aortic stenosis, even with severe left heart failure, pulmonary hypertension can be fully reversible and a significant improvement in both rest and effort hemodynamic parameters can be expected.

Irreversible poor pulmonary venous compliance can worsen the natural course of patients with high pulmonary capillary wedge pressure, especially those with mitral stenosis, but nitrates (isosorbide dinitrate--ISDN), which have venodilatory properties, could increase this compliance in most patients. The aim of this study was to assess the hemodynamic effects of ISDN in patients with mitral stenosis, with special emphasis on the pulmonary venous compliance. Pulmonary venous compliance was estimated according to the Hirakawa equation (dV/dp = 0.4 x k2 x sV/(v-d)) in 39 patients with mitral stenosis during preoperative right heart catheterization with Vygon 5155-180 thermodilution catheters at rest and during exercise (25 W) in the supine position. This procedure was repeated after the application of 3.75 mg of Iso-Mack spray. Overall, ISDN increased pulmonary venous compliance significantly both at rest and during exercise (6.0 to 7.5 ml/mmHg and 6.0 to 7.6 ml/mmHg, respectively). The patients were divided into two groups according to their level of ISDN response; those with a good response of an increase of 15% or more in pulmonary venous compliance (Group I), and those with an increase of less than 15% (Group II). There were significant differences between these two groups in stroke volume index and heart rate. In Group I, while the mean right atrial pressure, mean pulmonary artery pressure and mean pulmonary wedge pressure all decreased significantly, there was a simultaneous insignificant decrease in the stroke volume index and an also insignificant increase in the heart rate.(ABSTRACT TRUNCATED AT 250 WORDS)

Leflunomide has been shown to be very effective in preventing and curing several autoimmune animal diseases. Further, this agent is as effective as cyclosporin A in preventing the rejection of skin and kidney transplants in rats. Preliminary results from patients suffering from severe cases of rheumatoid arthritis demonstrated that clinical and immunological parameters could be improved with leflunomide therapy. Mode of action studies revealed that this substance antagonizes the proliferation inducing activity of several cytokines and is cytostatic for certain cell types. In this light, we could show that tyrosine phosphorylation of the RR-SRC peptide substrate and the autophosphorylation of the epidermal growth factor (EGF) receptor were, dose dependently, inhibited by leflunomide. EGF activates the intrinsic tyrosine kinase of its receptor, which stimulates the phosphorylation of a variety of peptides, the amino acid residue in all cases is tyrosine. These results indicate that much of leflunomide's activity could be due to the inhibition of tyrosine-kinase(s), which is an important general mechanism for the proliferation of various cell types. Thus, leflunomide, which is effective against autoimmune diseases and reactions leading to graft rejection, would seem to have a mode of action separating it from known immunosuppressive drugs.

The influence of chromophore solubility enhancements on photorefractive grating rise time and device lifetime is investigated. Three azo chromophores differing primarily in compatibility with a polyvinylcarbazole host polymer were synthesized. Aromatic substitutions to the chromophore increased the device lifetime from several days to years although electric-field-induced poling experiments indicated that chromophore orientational mobility is severely hindered, resulting in photorefractive grating rise times approaching several hours. The incorporation of a flexible butyl chain to the aromatic substituted chromophores significantly enhanced the orientational mobility. These chromophores could be loaded as high as 60wt% with no degradation in transparency for one year following fabrication.

Leflunomide is a novel immunomodulatory drug shown to be very effective in animal models of autoimmune diseases and transplantation rejection, as well as in human rheumatoid arthritis. Leflunomide's main metabolite, A77 1726, has been shown to be reversibly antiproliferativein vitro. Pursuing this, we performed cell cycle analysis by flow cytometry of a B-cell lymphoma line and found that at concentrations >2.5 μM cells accumulated in the early S-phase. In order to determine A77 1726's effects on cell activation, human peripheral blood lymphocytes (PBL) were cultured in the presence of PHA or OKT 3 antibody. Flow cytometric evaluation of IL-2 and transferrin receptor expression exhibited a dose-dependent inhibition of these activation markers (10–100 μM). Further, using the polymerase chain reaction, we investigated the ability of leflunomide to impair the transcription of the IL-2-R gene. We found that A77 1726 did not significantly decrease IL-2-R α-chain mRNA expression regardless of stimulation. It seems that leflunomide's main metabolite did not affect IL-2-R at the level of gene transcription, and thus its effects could be due to impairment of post-translational events. Taken together, these studies demonstrate that leflunomide: (1) impairs activation of quiescent lymphocytes (reduction of IL-2-R expression), without inhibiting IL-2-R mRNA formation; (2) reversibly inhibits proliferation by holding resting lymphocytes in the G0-phase and activated cells in the early S-phase of the cell cycle. Thus, this compound may exert its effects through influencing two important aspects of an immune response, i.e. activation and proliferation of lymphocytes.

Surface cleaning techniques used for semi-insulating GaAs substrates prior to epitaxial growth can have an important and sometimes detrimental effect on the quality and characteristics of epitaxial layers that are grown on them. We observe that a HF rinse followed by a 5:1:1 H 2 SO 4 :H 2 O 2 :H 2 O etch and H 2 O rinse drastically reduced the maximum concentrations and total amount of both SIMS detected S and Si for MOCVD grown GaAs undoped epitaxial layers. Subsequent final HCl and H 2 O reduced the S interfacial residues to the SIMS detection limit. Total amounts of residual Si are estimated to be equivalent to 10 -2 to 10 -3 monolayers. Residual S is less. Alternately the S residue can be comparable reduced by a HF rinse followed by a NH 4 OH:H 2 O 2 :H 2 O etch and H 2 O rinse. Hot aqueous HCl removes S but not Si residues. The Si residue is not electrically active and most likely exists as islands of SiO 2 . The relative significance of the impurity residues is most pronounced for halide VPE, smaller for MBE and least for MOCVD grown GaAs epitaxial layers.

This paper describes the Si-doping of GaAs that was grown using the AsCl3:H2:GaAs, Ga Chemical vapor deposition process. The doping sources were AsCl3:SiCl4 liquid solutions which proved to be highly reproducible for Si doping within the range, 1×1O16 to 2×1019 cm−3. Incorporation of Si into the GaAs apparently occurs under near equilibrium conditions. This point is considered in detail and the consequences experimentally utilized to grow n, n+ bilayers using a single AsCl3:SiCl4 doping solution. Si impurity profiles based upon differential capacitance and SIMS data are presented. These can be very abrupt for n, n+ structures with order of magnitude changes occurring within 500 A. For the 1×1016 to 8×l018 cm−3 doped samples the mobilities at 78 and 298°K are comparable to the higher values reported for GaAs thin films grown by CVD. Power FET devices made from this material have demonstrated an output density of 0.86 watts/mm at 10 GHz.

We have studied the chemical and electrical properties of Si doped GaAs layers grown from SiH4. - TMG - ASH3 - H2 at atmospheric pressure in a large scale metal-organic chemical vapor deposition (MOCVD) reactor. Excellent mobilities at the high doping levels imply doping efficiency in our reactor is higher than previously reported. We have measured extremely uniform doping and doping-thickness product of the Si doped epilayers. The importance of reactor configuration and the surface controlled growth reaction is illustrated by the relatively temperature independent dopant incorporation and the growth rate dependence of the GaAs on the bulk Fermi level.