Hypervolemia rather than arterial calcification and extracoronary atherosclerosis is the main determinant of pulse pressure in hemodialysis patients

Introduction

Pulse pressure (PP) has been reported as an independent predictor of cardiovascular mortality in hemodialysis patients. In this study, we aimed to investigate association of PP with echocardiographic and vascular structural changes such as atherosclerosis and arterial calcifications in HD patients.

Patients and methods

In this cross-sectional study, 108 chronic hemodialysis patients (49 male, 59 female, mean age: 46?±?13?years) were included. Biochemical analyses, echocardiographic and high-resolution carotid Doppler examinations were done. Aortic wall and coronary artery calcifications were measured with electron beam computed tomography. The degree of carotid artery stenosis was measured at four different sites (communis, bulbus, interna and externa) in both carotid arteries.

Results

PP was strongly correlated with systolic (r: 0.82) and diastolic (r: 0.33) blood pressure, left ventricular mass index (r: 0.58), left ventricle end diastolic diameter (r: 0.38) and weakly correlated with aortic wall calcification score (r: 0.26) and carotid plaque score (r: 0.27), but not with coronary artery calcification score. Patients with carotid plaque had higher PP than patients without plaque (50?±?16?mmHg versus 44?±?14?mmHg, P?=?0.05). Patients were divided into three groups according to aortic wall calcification score. PP was significantly higher in patients with higher aortic wall calcification (54?±?16?mmHg) than patients with lower aortic wall calcification (44?±?15?mmHg, P?=?0.04). However, on multivariate linear regression analysis for predicting PP, the only significant factor retained was left ventricle end diastolic diameter.

Conclusion

PP was weakly associated with large vessel calcification and atherosclerosis in hemodialysis patients. The bulk of the effect on PP seems to be due to hypervolemia.     

Antibody responses against influenza A(H1N1)pdm09 virus after sequential vaccination with pandemic and seasonal influenza vaccines in Finnish healthcare professionals

Background Influenza A(H1N1)pdm09 virus has been circulating in human population for three epidemic seasons. During this time, monovalent pandemic and trivalent seasonal influenza vaccination against this virus have been offered to Finnish healthcare professionals. It is, however, unclear how well vaccine‐induced antibodies recognize different strains of influenza A(H1N1)pdm09 circulating in the population and whether the booster vaccination with seasonal influenza vaccine would broaden the antibody cross‐reactivity. Objectives Influenza vaccine‐induced humoral immunity against several isolates of influenza A(H1N1)pdm09 virus was analyzed in healthcare professionals. Age‐dependent responses were also analyzed. Methods Influenza viruses were selected to represent viruses that circulated in Finland during two consecutive influenza epidemic seasons 2009–2010 and 2010–2011. Serum samples from vaccinated volunteers, age 20–64 years, were collected before and after vaccination with AS03‐adjuvanted pandemic and non‐adjuvanted trivalent seasonal influenza vaccine that was given 1 year later. Results Single dose of pandemic vaccine induced a good albeit variable antibody response. On day 21 after vaccination, depending on the virus strain, 14–75% of vaccinated had reached antibody titers (≥1:40) considered seroprotective. The booster vaccination 1 year later with a seasonal vaccine elevated the seroprotection rate to 57–98%. After primary immunization, younger individuals (20–48 years) had significantly higher antibody titers against all tested viruses than older persons (49–64 years) but this difference disappeared after the seasonal booster vaccination. Conclusions Even a few amino acid changes in influenza A HA may compromise the vaccine‐induced antibody recognition. Older adults (49 years and older) may benefit more from repeated influenza vaccinations.     

Incidence of Appropriate Shock in Implantable Cardioverter-Defibrillator Patients With Improved Ejection Fraction

BackgroundHeart failure with recovered ejection fraction (EF) is a recently described clinical entity. There is insufficient information on the management of implantable-cardioverter defibrillator (ICD) patients with improved EF at generator replacement.Methods and ResultsWe examined the incidence of appropriate shocks in 91 consecutive patients with ICDs for primary prevention of sudden death who underwent generator replacement. Improved EF was defined as both EF >35% at generator replacement and increase in EF by ≥10% since original implantation. Patients were 70 ± 11 years old, and 76% had ischemic cardiomyopathy. At generator replacement, 25 patients (27%) had improved EF (0.49 ± 0.08 vs 0.31 ± 0.07 at baseline; P < .0001). Over 6.2 ± 2.2 years of follow-up after original implantation, 9 patients (36%) with improved EF versus 19 (29%) with unchanged EF had appropriate ICD shocks (P = .51). Incidence of appropriate ICD shocks was similar between the two groups before (P = .90) and after (P = .97) generator replacement. Of the 9 improved EF patients with appropriate shock, 4 had shocks before generator replacement, 2 had shocks before and after generator replacement, and 3 patients, who never had shocks before, had their first shock after generator replacement.ConclusionsSome ICD patients whose EF improves to >35% at generator replacement remain at risk for appropriate ICD shocks.     

Evaluation of the driving ability in disabled persons: A practitioners' view

Purpose and methods.?The purpose of this paper is to present, on the basis of four genuine cases from the Rehabilitation Research Unit of Oulu University, the theoretical frame in which evaluations of driving ability of disabled persons can be made.

Results.?First, it is not the operations with the control devices but the correct mental actions which the driver carries out with the help of the control devices which are crucial for safe driving. Second, driving ability is only partly a biomedical object of research and one ought to avoid an excessive medicalisation of an evaluation of driving ability. Third, the driver meets traffic situations not by his or her separate biological or psychological functions, such as vision, attention, memory, thinking, motives, but as an integrated whole, as a personality.

Conclusions.?By its complexity an evaluation of driving ability can be compared to an evaluation of working capacity where often a multidisciplinary team is needed. When evaluating driving ability we have to take a step from low-level motor operations towards high-level mental actions, from the measurement of acuity of eyesight towards the testing of the flexibility of perception, from the diagnosis-based evaluation to the patient-based evaluation, from using the common pencil?–?paper tests towards the traffic-related task-specific tests and from the testing of separate single general non-driving-related factors towards an evaluation of the theoretically based driving performance as whole.     

Traumatic lingual ulcer in a child: Riga–Fede disease

Riga–Fede disease RFD is an extremely rare, benign inflammatory disorder characterized by reactive, traumatic ulceration of the oral mucosa especially located on the tongue. It is most commonly associated with natal or neonatal teeth in newborns. Mucosal lesions are often caused by repetitive traumatic damage due to backward and forward motions of the tongue over the lower incisors. Failure to diagnose and treat these lesions properly may result in inadequate food intake, growth retardation and permanent lingual deformity. We report a 15-month-old healthy infant with tongue ulcer diagnosed as RFD based on history and clinical features.     

Vascular involvement in Beh?et's disease.

Beh?et's disease (BD) is a multisystem disorder characterized by recurrent oral and genital ulcerations with uveitis. At onset it may present with manifestations of vascular involvement instead of the classical triad. We analyzed 137 patients with BD and 38 had vascular involvement with a prevalence of 27.7%. Male to female ratio was 4.4 and associations of positive pathergy test (76.3%) and eye lesions (57.8%) were higher compared to patients without vascular involvement. Patients with subcutaneous thrombophlebitis were more likely to develop major venous occlusions (22.2%) in the lower extremities and inferior vena cava. Arterial lesions were less frequent features constituting 12.0% of vascular complications in BD.     

Effects of oophorectomy and hormone replacement therapy on the pulsatility indices of hepatic and renal arteries.

OBJECTIVE: To investigate the flow velocity waveform changes of the hepatic and renal arteries in women with surgical menopause who received hormone replacement therapy versus those who did not. METHODS: Eighty women who had undergone surgical menopause were divided into 2 groups. The first group (n = 38) consisted of patients who did not receive estrogen treatments after surgery; patients in the second group (n = 42) did receive treatments. The hepatic and renal arteries of patients in both groups were examined by duplex Doppler ultrasonography before the commencement of hormone replacement therapy and after 2 years of treatment, and the pulsatility indices were calculated. RESULTS: No significant differences were detected in the renal and hepatic artery pulsatility indices of patients in the estrogen treatment group (group 2) before and after total abdominal hysterectomy and bilateral salpingo-oophorectomy (P > .05). No significant differences in preoperative and postoperative hepatic arterial pulsatility indices were detected among patients in group 1 (P > .05). Renal artery pulsatility indices measured before and after total abdominal hysterectomy and bilateral salpingooophorectomy did show a statistically significant difference in group 1 (P < .001). In addition, a statistically significant difference was detected before and after surgery in both groups when pulsatility indices were measured at the second-year control dose. CONCLUSIONS: Hepatic arterial pulsatility indices are not affected in postmenopausal women, but renal artery pulsatility indices rise to some extent in women not receiving hormone replacement therapy.     

In situ measurement of solvent-mediated phase transformations during dissolution testing

In this study, solvent-mediated phase transformations of theophylline (TP) and nitrofurantoin (NF) were measured in a channel flow intrinsic dissolution test system. The test set-up comprised simultaneous measurement of drug concentration in the dissolution medium (with UV-Vis spectrophotometry) and measurement of the solid-state form of the dissolving solid (in situ with Raman spectroscopy). The solid phase transformations were also investigated off-line with scanning electron microscopy. TP anhydrate underwent a transformation to TP monohydrate, and NF anhydrate (form beta) to NF monohydrate (form II). Transformation of TP anhydrate to TP monohydrate resulted in a clear decrease in the dissolution rate, while the transformation of NF anhydrate (form beta) to NF monohydrate (form II) could not be linked as clearly to changes in the dissolution rate. The transformation of TP was an order of magnitude faster than that of NF. The presence of a water absorbing excipient, microcrystalline cellulose, was found to delay the onset of the transformation of TP anhydrate. Combining the measurement of drug concentration in the dissolution medium with the solid phase measurement offers a deeper understanding of the solvent-mediated phase transformation phenomena during dissolution.     

Depth Profiling of Compression-Induced Disorders and Polymorphic Transition on Tablet Surfaces with Grazing Incidence X-ray Diffraction

Purpose The importance of induced crystal disorders like crystallite size, crystal defects, and amorphicity with respect to the dissolution rate of the drug has been discussed in many cases. Thus, the characterization of these properties is of great importance in the pharmaceutical formulation development, although the exact correlation between disorders and dissolution rate is still unclear. The aim of this study was to analyze pharmaceutical tablets with grazing incidence X-ray diffraction, which enables the depth profiling of the crystallographic properties of the tablets. To study and clarify the potential of grazing incidence diffraction in the analysis of pharmaceutical materials, the effect of the compaction process on the surface of tablets was examined. Methods Carbamazepine, tolbutamide, and chlorpropamide tablets, compacted using different compression pressures, were studied using grazing incidence angle X-ray diffraction. The effects of compression on the crystallographic properties were investigated as a function of the distance from the tablet surface. Results The surfaces of the tolbutamide and chlorpropamide tablets were disordered due to the compression. The manifestation of the disorder was deduced to be due to amorphicity, small crystallite size, and amount of crystal defects. The changes were mainly on the surface and diminished strongly as a function of the distance from the surface of the tablet. Moreover, the changes were dependent on the compression pressure used. The changes on the surface of the carbamazepine tablets were also due to the compression but these changes were not clearly dependent on the depth nor the compression pressure. The partial phase transition took place in the chlorpropamide tablets due to the compression. The magnitude of the transition was not highest on the surface because amorphization and texturization also took place on the tablet surface during the compression. Conclusions The present study proved that grazing incidence X-ray diffraction is a potential novel research tool to reveal crystallographic transformations taking place on the surfaces of the tablets induced, for example, by compression pressure.