Assessment of groundwater vulnerability to nitrates using the GIS-based DRASTIC and SI methods: a case study in Zacharo area, Greece.

A vulnerability assessment of the aquifers in the agricultural area of Zacharo in SW, Peloponnese, Greece, was conducted using the DRASTIC index and the susceptibility index (SI). Sensitivity analysis was conducted and thematic maps for each parameter were generated to analyse the impact of individual parameter on the collective groundwater vulnerability. Results derived from the DRASTIC and SI maps revealed that the extremely highly vulnerable zones are concentrated at three coastal sites in the western part of the study area. Data from these maps also indicate low vulnerability areas throughout the eastern part of the region. The distribution of nitrate concentrations in groundwater is better correlated with the DRASTIC (79.2%) compared to SI (60.2%). Neither method takes into consideration the impact of dilution and nitrate to ammonium reduction, on the nitrate content of groundwater, thus overestimating the vulnerability index. Moreover, the SI method overestimates the impact of olive groves' land use type on the susceptibility index, thus resulting to a lower correlation with the observed nitrate concentrations.

Epidemiology of Hypertension among Patients on Peritoneal Dialysis Using Standardized Office and Ambulatory Blood Pressure Recordings.

INTRODUCTION: Prior studies conducted in peritoneal dialysis (PD) patients in the late 1990s provided considerably variable estimates of the prevalence and control of hypertension. The present study aimed to investigate the current state of hypertension management in this high-risk population. METHODS: In 140 stable PD patients, we performed standardized automated office blood pressure (BP) measurements and 24-h ambulatory BP monitoring (ABPM) using the Mobil-O-Graph device (IEM, Germany). Office and ambulatory hypertension was diagnosed in patients with office BP ≥140/90 mm Hg and 24-h BP ≥130/80 mm Hg, respectively. Patients treated with ≥1 BP-lowering medications were also classified as hypertensives. RESULTS: The prevalence of office and ambulatory hypertension was 92.9% and 95%, respectively. In all, 92.1% of patients were being treated with an average of 2.4 BP-lowering medications daily. Adequate BP control was achieved in 52.3% and 38.3% of hypertensives by office BP and ABPM, respectively. The agreement between these 2 techniques in the identification of patients with BP levels above the diagnostic thresholds of hypertension was moderate (k-statistic: 0.524). In all, 5% of patients were normotensives with both techniques, 31.4% had controlled hypertension, 5% had white-coat hypertension, 19.3% had masked hypertension, and 39.3% had sustained hypertension. Isolated nocturnal hypertension was detected in 23.6% of patients, whereas no patient had isolated daytime hypertension. CONCLUSION: Among PD patients, hypertension is highly prevalent and remains often inadequately controlled. The use of ABPM enables the better classification of severity of hypertension and identification of isolated nocturnal hypertension, which is a common BP phenotype in the PD population.

Contemporary Data on the Status and Medical Management of Acute Heart Failure.

PURPOSE OF REVIEW: Acute heart failure (AHF) is among the leading causes for unplanned hospital admission. Despite advancements in the management of chronic heart failure, the prognosis of AHF remains poor with high in-hospital mortality and increased rates of unfavorable post-discharge outcomes. With this review, we aim to summarize current data on AHF epidemiology, focus on the different patient profiles and classifications, and discuss management, including novel therapeutic options in this area. RECENT FINDINGS: There is significant heterogeneity among patients admitted for AHF in their baseline characteristics, heart failure (HF) aetiology and precipitating factors leading to decompensation. A novel classification scheme based on four distinct clinical scenarios has been included in the most recent ESC guidelines, in an effort to better risk stratify patients and guide treatment. Intravenous diuretics, vasodilators, and inotropes remain the cornerstone of management in the acute phase, and expansion of use of mechanical circulatory support has been noted in recent years. Meanwhile, many treatments that have proved their value in chronic heart failure demonstrate promising results in the setting of AHF and research in this field is currently ongoing. Acute heart failure remains a major health challenge with high in-hospital mortality and unfavorable post-discharge outcomes. Admission for acute HF represents a window of opportunity for patients to initiate appropriate treatment as soon as possible after stabilization. Future studies are needed to elucidate which patients will benefit the most by available therapies and define the optimal timing for treatment implementation.

Prevalence and control of hypertension among patients on haemodialysis.

BACKGROUND: Earlier studies provided considerably variable estimates on the prevalence and control rates of hypertension in haemodialysis because of their heterogeneity in definitions and blood pressure (BP) measurement techniques applied to detect hypertension. MATERIALS AND METHODS: In this cross-sectional study, 116 clinically stable haemodialysis patients from 3 dialysis centres of Northern Greece underwent home BP monitoring for 1 week with the validated automatic device HEM-705 (Omron, Healthcare). Routine BP recordings taken before and after dialysis over 6 consecutive sessions were also prospectively collected and averaged. Hypertension was defined as: (a) 1-week averaged home BP ≥ 135/85 mm Hg; (b) 2-week averaged predialysis BP ≥ 140/90 mm Hg; and (c) 2-week averaged postdialysis BP ≥ 130/80 mm Hg. Participants on treatment with ≥1 antihypertensives were also classified as hypertensives. RESULTS: The prevalence of hypertension was 88.8% by home, 86.2% by predialysis and 91.4% by postdialysis BP recordings. In all, 96 participants (82.7%) were being treated with an average of 2.0 ± 1.1 antihypertensive medications. Among drug-treated participants, 32.6% were controlled by home, 50.5% by predialysis and 45.3% by postdialysis BP recordings. In multivariate logistic regression analysis, greater use of antihypertensive medications and postdialysis overhydration, assessed with bioimpedance spectroscopy, were both independently associated with higher odds of inadequate home BP control. CONCLUSIONS: This study shows that the prevalence, but mainly the control rates of hypertension in patients on haemodialysis, differs between peridialytic and interdialytic BP recordings. Therefore, the wider use of home BP monitoring may improve the determination of BP control status in this high-risk population.

10-year-long survival in a PD patient with severe calcifying encapsulating peritoneal sclerosis treated with tamoxifen: a case-report.

BACKGROUND: Encapsulating-peritoneal-sclerosis (EPS) is a rare, but serious and life-threatening complication of peritoneal dialysis (PD). Treatment of EPS consists of discontinuation of PD and maintenance of nutritional status, whereas the role of corticosteroids, tamoxifen and other immunosuppresive agents is not yet fully elucidated. CASE-PRESENTATION: We report the case of a 28-year-old patient, who developed a severe form of calcifying EPS after a 6-year-long therapy with automated PD. The clinical presentation was severe with repeated episodes of total bowel obstruction, weight loss and malnutrition that mandated his prolonged hospitalization. Initial treatment included corticosteroids and tamoxifen (20 mg/day) with a clinically meaningful improvement in gastrointestinal function and nutritional status over the first 6-12 months. Corticosteroids were discontinued at 18 months, but owing to persistence of calcifying lesions and peritoneal thickening in repeated computed-tomography (CT) scans, tamoxifen remained unmodified at a low-dose of 20 mg/day for a 10-year-long period. During follow-up, the patient remained symptoms-free in an excellent clinical condition and the CT findings were unchanged. CONCLUSIONS: Long-term administration of tamoxifen was not accompanied by any drug-related adverse effects and potentially exerted a beneficial action on down-regulation of inflammatory and fibrotic processes and improvement of gastrointestinal function, nutritional status and overall health-related quality of life.

Icodextrin-associated generalized exfoliative skin rash in a CAPD patient: a case-report.

BACKGROUND: Icodextrin is a starch-derived, water soluble glucose polymer, which is used as an alternative to glucose in order to enhance dialytic fluid removal in peritoneal dialysis patients. Although the safety and efficacy of icodextrin is well-established, its use in everyday clinical practice has been associated with the appearance of skin rashes and other related skin reactions. CASE PRESENTATION: Herein, we report the rare case of a 91-year-old woman with a history of severe congestive heart failure, who initiated continuous ambulatory peritoneal dialysis with icodextrin-based dialysate solutions and 15 days after the initial exposure to icodextrin developed a generalized maculopapular and exfoliative skin rash extending over the back, torso and extremities. Discontinuation of icodextrin and oral therapy with low-dose methyl-prednisolone with quick dose tapering improved the skin lesions within the following days. CONCLUSIONS: This case report highlights that skin hypersensitivity is a rare icodextrin-related adverse event that should be suspected in patients manifesting skin reactions typically within a few days or weeks after the initial exposure.

Accuracy of a Newly-Introduced Oscillometric Device for the Estimation of Arterial Stiffness Indices in Patients on Peritoneal Dialysis: A Preliminary Validation Study.

The aim of the present study was to compare the aortic systolic blood pressure (aSBP), heart-rate-adjusted augmentation index (AIx75), and pulse wave velocity (PWV) obtained using the Mobil-O-Graph (IEM, Stolberg, Germany) and SphygmoCor (AtCor, Sydney, Australia) devices in patients receiving peritoneal dialysis (PD).After a 10-minute rest in the supine position, the Mobil-O-Graph and SphygmoCor devices were applied in randomized order in 27 consecutive PD patients. The agreement between the measurements produced by the Mobil-O-Graph and SphygmoCor devices was explored using Bland-Altman analysis.The Mobil-O-Graph-derived aSBP, AIx75, and PWV did not differ from the same measurements obtained with SphygmoCor (aSBP: 120.5 ± 18.2 mmHg vs. 124.4 ± 19.0 mmHg, p = 0.438; AIx75: 27.0% ± 12.4% vs. 24.5% ± 10.6%, p = 0.428; PWV: 9.5 ± 2.1 m/s vs. 10.1 ± 3.1 m/s, p = 0.397). The slight difference in the estimation of aSBP is possibly explained by the difference in brachial SBP used for the calibration of the devices (131.0 ± 20.6 mmHg vs. 134.5 ± 19.7 mmHg, p = 0.525). Mobil-O-Graph-derived measurements correlated strongly with paired measurements obtained with the SphygmoCor device. Bland-Altman plots showed no evidence of asymmetry and a wide range of agreement between the two devices.Our study shows acceptable agreement between Mobil-O-Graph and SphygmoCor in the estimation of arterial stiffness indices in PD patients. Accordingly, the Mobil-O-Graph device accurately performs aortic ambulatory blood pressure monitoring in this population.

Evaluation of a novel brachial cuff-based oscillometric method for estimating central systolic pressure in hemodialysis patients.

BACKGROUND/AIMS: Elevated wave reflections and arterial stiffness, as well as ambulatory blood pressure (BP) are independent predictors of cardiovascular risk in end-stage-renal-disease. This study is the first to evaluate in hemodialysis patients the validity of a new ambulatory oscillometric device (Mobil-O-Graph, IEM, Germany), which estimates aortic BP, augmentation index (AIx) and pulse wave velocity (PWV). METHODS: Aortic SBP (aSBP), heart rate-adjusted AIx (AIx(75)) and PWV measured with Mobil-O-Graph were compared with the values from the most widely used tonometric device (Sphygmocor, ArtCor, Australia) in 73 hemodialysis patients. Measurements were made in a randomized order after 10 min of rest in the supine position at least 30 min before a dialysis session. Brachial BP (mercury sphygmomanometer) was used for the calibration of Sphygmocor's waveform. RESULTS: Sphygmocor-derived aSBP and AIx(75) did not differ from the relevant Mobil-O-Graph measurements (aSBP: 136.3 ± 19.6 vs. 133.5 ± 19.3 mm Hg, p = 0.068; AIx(75): 28.4 ± 9.3 vs. 30.0 ± 11.8%, p = 0.229). The small difference in aSBP is perhaps explained by a relevant difference in brachial SBP used for calibration (146.9 ± 20.4 vs. 145.2 ± 19.9 mm Hg, p = 0.341). Sphygmocor PWV was higher than Mobil-O-Graph PWV (10.3 ± 3.4 vs. 9.5 ± 2.1 m/s, p < 0.01). All 3 parameters estimated by Mobil-O-Graph showed highly significant (p < 0.001) correlations with the relevant measurements of Sphygmocor (aSBP, r = 0.770; AIx(75), r = 0.400; PWV, r = 0.739). The Bland-Altman Plots for aSBP and AIx(75) showed acceptable agreement between the two devices and no evidence of systemic bias for PWV. CONCLUSION: As in other populations, acceptable agreement between Mobil-O-Graph and Sphygmocor was evident for aSBP and AIx(75) in hemodialysis patients; PWV was slightly underestimated by Mobil-O-Graph.

Hemodiafiltration does not have additional benefits over hemodialysis on arterial stiffness, wave reflections and central aortic pressures.

BACKGROUND/AIMS: The hypothesis that dialytic modality affects arterial stiffness was never investigated. This study includes comparative evaluation of hemodiafiltration versus hemodialysis on arterial function during first and second weekly dialysis sessions. METHODS: 24 patients receiving hemodiafiltration and another 24 age- and sex-matched controls receiving hemodialysis were included. Patients were evaluated before and after first and second weekly dialysis sessions. Applanation tonometry of peripheral arteries was applied to determine aortic and brachial pulse wave velocity and heart rate-adjusted augmentation index (AIx(75)). RESULTS: Hemodiafiltration and hemodialysis reduced AIx(75), but not aortic and brachial pulse wave velocity. Intradialytic reductions in AIx(75) did not differ between hemodiafiltration and hemodialysis in first and mid-week dialysis. In multivariate linear regression, predictors of intradialytic reduction in AIx(75) were changes in body weight and central aortic systolic blood pressure, but not dialytic modality. CONCLUSION: This study showed that hemodiafiltration has similar effects with hemodialysis on wave reflections and stiffness.

DExplore: An Online Tool for Detecting Differentially Expressed Genes from mRNA Microarray Experiments.

Microarray experiments, a mainstay in gene expression analysis for nearly two decades, pose challenges due to their complexity. To address this, we introduce DExplore, a user-friendly web application enabling researchers to detect differentially expressed genes using data from NCBI's GEO. Developed with R, Shiny, and Bioconductor, DExplore integrates WebGestalt for functional enrichment analysis. It also provides visualization plots for enhanced result interpretation. With a Docker image for local execution, DExplore accommodates unpublished data. To illustrate its utility, we showcase two case studies on cancer cells treated with chemotherapeutic drugs. DExplore streamlines microarray data analysis, empowering molecular biologists to focus on genes of biological significance.

Gender-Related Differences in the Levels of Ambulatory BP and Intensity of Antihypertensive Treatment in Patients Undergoing Peritoneal Dialysis.

Prior studies have shown that among patients with chronic kidney disease not yet on dialysis, the faster progression of kidney injury in men than in women is, at least partly, explained by sex differences in ambulatory blood pressure (BP) control. The present study aimed to investigate potential differences in the levels of ambulatory BP and intensity of antihypertensive treatment between men and women with end-stage kidney disease undergoing long-term peritoneal dialysis (PD). In a case-control design, 48 male PD patients were matched for age and heart failure status with 48 female patients in a 1:1 ratio. Ambulatory BP monitoring was performed with an oscillometric device, the Mobil-O-Graph (IEM, Stolberg, Germany). The BP-lowering medications actually taken by the patients were prospectively recorded. No gender-related differences were observed in 24 h systolic BP (129.0 ± 17.9 vs. 128.5 ± 17.6 mmHg, p = 0.890). In contrast, 24 h diastolic BP was higher in men than in women (81.5 ± 12.1 vs. 76.8 ± 10.3 mmHg, p = 0.042). As compared with women, men were being treated with a higher average number of antihypertensive medications daily (2.4 ± 1.1 vs. 1.9 ± 1.1, p = 0.019) and were more commonly receiving calcium-channel-blockers (70.8% vs. 43.8%, p = 0.007) and ß-blockers (85.4% vs. 66.7%, p = 0.031). In conclusion, the present study shows that among PD patients, the levels of ambulatory BP and intensity of antihypertensive treatment are higher in men than in women. Longitudinal studies are needed to explore whether these gender-related differences in the severity of hypertension are associated with worse cardiovascular outcomes for male patients undergoing PD.

On the output factor measurements of the CyberKnife iris collimator small fields: Experimental determination of the k(Q(clin),Q(msr) ) (f(clin),f(msr) ) correction factors for microchamber and diode detectors.

PURPOSE: To measure the output factors (OFs) of the small fields formed by the variable aperture collimator system (iris) of a CyberKnife (CK) robotic radiosurgery system, and determine the k(Q(clin),Q(msr) ) (f(clin),f(msr) ) correction factors for a microchamber and four diode detectors. METHODS: OF measurements were performed using a PTW PinPoint 31014 microchamber, four diode detectors (PTW-60017, -60012, -60008, and the SunNuclear EDGE detector), TLD-100 microcubes, alanine dosimeters, EBT films, and polymer gels for the 5 mm, 7.5 mm, 10 mm, 12.5 mm, and 15 mm iris collimators at 650 mm, 800 mm, and 1000 mm source to detector distance (SDD). The alanine OF measurements were corrected for volume averaging effects using the 3D dose distributions registered in polymer gel dosimeters. k(Q(clin),Q(msr) ) (f(clin),f(msr) ) correction factors for the PinPoint microchamber and the diode dosimeters were calculated through comparison against corresponding polymer gel, EBT, alanine, and TLD results. RESULTS: Experimental OF results are presented for the array of dosimetric systems used. The PinPoint microchamber was found to underestimate small field OFs, and a k(Q(clin),Q(msr) ) (f(clin),f(msr) ) correction factor ranging from 1.127 ± 0.022 (for the 5 mm iris collimator) to 1.004 ± 0.010 (for the 15 mm iris collimator) was determined at the reference SDD of 800 mm. The PinPoint k(Q(clin),Q(msr) ) (f(clin),f(msr) ) correction factor was also found to increase with decreasing SDD; k(Q(clin),Q(msr) ) (f(clin),f(msr) ) values equal to 1.220 ± 0.028 and 1.077 ± 0.016 were obtained for the 5 mm iris collimator at 650 mm and 1000 mm SDD, respectively. On the contrary, diode detectors were found to overestimate small field OFs and a correction factor equal to 0.973 ± 0.006, 0.954 ± 0.006, 0.937 ± 0.007, and 0.964 ± 0.006 was measured for the PTW-60017, -60012, -60008 and the EDGE diode detectors, respectively, for the 5 mm iris collimator at 800 mm SDD. The corresponding correction factors for the 15 mm iris collimator were found equal to 0.997 ± 0.010, 0.994 ± 0.009, 0.988 ± 0.010, and 0.986 ± 0.010, respectively. No correlation of the diode k(Q(clin),Q(msr) ) (f(clin),f(msr) ) correction factors with SDD was observed. CONCLUSIONS: This work demonstrates an experimental procedure for the determination of the k(Q(clin),Q(msr) ) (f(clin),f(msr) ) correction factors required to obtain small field OF results of increased accuracy.

On the effect of dose delivery temporal domain on the biological effectiveness of central nervous system CyberKnife radiosurgery applications: theoretical assessment using the concept of biologically effective dose.

OBJECTIVE: The diversity in technical configuration between clinically available radiosurgery systems, results in accordingly diverse treatment times for the same physical dose prescription, spanning from several min to more than 1 h. This, combined with evidence supporting the impact of dose delivery temporal pattern on the bio-effectiveness of low-LET radiation treatments, challenges the 'acute exposure' assumption adopted clinically to estimate the biological outcome of a given treatment scheme under the concept of biologically effective dose (BED).Approach: In this work, the treatment plans of 30 patients underwent CyberKnife radiosurgery for vestibular schwannoma (VS), prescribing a marginal dose of 13 Gy to the tumor, were retrospectively reviewed and the corresponding dose distributions were resolved in the temporal domain. For this purpose, the dose delivery timeline for each treatment was calculated based on relevant treatment plan data and technical specifications of the CyberKnife system, while dosimetry data were independently acquired on a CT-based digital model of each patient using an in-house developed dose calculation algorithm.Main results: Results showed that CyberKnife delivers highly inhomogeneous dose rate distributions in the temporo-spatial domain. This influences the delivered BED levels due to alterations in the sublethal damage repair (SLR) occurring within the treatment session. Using a BED framework involving SLR effects, it was shown that each physical dose iso-surface is associated with a BEDslrrange. For the patient cohort studied, a typical range of 2%, with respect to the mean BEDslrvalue was found at 1σ.Significance: The marginal BEDslrdelivered to the tumor by the prescription dose iso-surface deteriorates with treatment time, involving both beam-on time and beam-off gaps. For treatment time,T, between 21 and 50 min, this can be expressed byBEDslr(Gy2.47)=-0.35±2.8%∙Tmin+(76.74±0.4%).Compared to the acute exposure approach, a BED 'loss' of 21% is associated with the delivery of 13 Gy to the VS-tumor in 35 min.

Prevalence, recurrence and seasonal variation of hyperkalemia among patients on hemodialysis.

PURPOSE: Observational studies have shown that among patients on hemodialysis, hyperkalemia is strongly associated with excess risk for cardiovascular-related hospitalizations and sudden cardiac death. However, the actual burden of hyperkalemia, the rates of its recurrence and seasonality in its variation still remain unclear. METHODS: Between June 2020 and May 2021, 1786 mid-week pre-dialysis serum potassium (sK) measurements were retrospectively recorded from 149 patients receiving thrice-weekly hemodialysis in a single-center in Thessaloniki, Greece. The prevalence, recurrence and seasonal variation of hyperkalemia were assessed using three pre-specified sK thresholds (≥ 5.1, ≥ 5.5 and ≥ 6.0 mmol/L). RESULTS: At baseline, 60.4%, 42.2% and 13.4% of patients had sK levels ≥ 5.1, ≥ 5.5 and ≥ 6.0 mmol/L, respectively. At any time-point during follow-up, 85.2%, 69.8% and 38.9% of patients experienced at least one hyperkalemic event ≥ 5.1, ≥ 5.5 and ≥ 6.0 mmol/L, respectively. Of the 104 patients experiencing an initial sK elevation ≥ 5.5 mmol/L, hyperkalemia at the same threshold reoccurred in 60.6% at month 1, in 47.1% at month 2 and in 46.1% at month 3 of follow-up. Seasonal variation was also observed, with the prevalence of hyperkalemia to be significantly higher in summer. Shorter delivered hemodialysis < 4 h/session (OR: 2.568; 95% CI 1.045-6.313) and the use of a high dialysate K concentration (OR: 14.646; 95% CI 2.727-78.647) were the 2 factors that were independently associated with hyperkalemia. CONCLUSION: The present study shows that among hemodialysis patients, the rates of hyperkalemia prevalence and recurrence are very high, reflecting the large unmet need to identify more effective potassium-lowering therapeutic interventions in this high-risk population.

Feeding during Dialysis Increases Intradialytic Blood Pressure Variability and Reduces Dialysis Adequacy.

Whether hemodialysis patients should be allowed or even encouraged to eat during dialysis remains a controversial topic. This cross-over study aimed to evaluate the impact of feeding during dialysis on intradialytic blood pressure (BP) profile and dialysis adequacy in 26 patients receiving thrice-weekly, in-center hemodialysis. Over three consecutive mid-week dialysis sessions, intradialytic BP was monitored using the Mobil-O-Graph device (IEM, Stolberg, Germany). Blood samples were also obtained for the determination of the urea reduction ratio (URR). At baseline, patients underwent dialysis without the provision of a meal. In phases A and B, a meal with either high-protein (1.5 gr/kg of body weight) or low-protein (0.7 gr/kg of body weight) content was administered 1 h after the initiation of dialysis. The sequence of meals (high-protein and low-protein or vice versa) was randomized. Average intradialytic systolic BP (SBP) was similar on all three occasions. However, compared with baseline, the standard deviation (SD) (11.7 ± 4.1 vs. 15.6 ± 7.6 mmHg, p < 0.01), coefficient of variation (CV) (9.5 ± 3.7% vs. 12.4 ± 6.0%, p < 0.01) and average real variability (ARV) (9.4 ± 3.9 vs. 12.1 ± 5.2 mmHg, p < 0.01) of intradialytic SBP were higher in phase A. Similarly, compared with the baseline evaluation, all three indices of intradialytic SBP variability were higher in phase B (SD: 11.7 ± 4.1 vs. 14.1 ± 4.5 mmHg, p < 0.05; CV: 9.5 ± 3.7% vs. 11.1 ± 3.8%, p < 0.05; ARV: 9.4 ± 3.9 vs. 10.9 ± 3.9 mmHg, p < 0.05). Compared with dialysis without a meal, the consumption of a high-protein or low-protein meal resulted in a lower URR (73.4 ± 4.3% vs. 65.7 ± 10.7%, p < 0.001 in phase A and 73.4 ± 4.3% vs. 67.6 ± 4.3%, p < 0.001 in phase B, respectively). In conclusion, in the present study, feeding during dialysis was associated with higher intradialytic SBP variability and reduced adequacy of the delivered dialysis.

Age dependence of brachial cuff-based ambulatory PWV in end-stage kidney disease patients undergoing long-term peritoneal dialysis.

BACKGROUND: The newly introduced device Mobil-O-Graph (IEM, Stolberg, Germany) combines brachial cuff oscillometry and pulse wave analysis, enabling the determination of pulse wave velocity (PWV) via complex mathematic algorithms during 24-h ambulatory blood pressure monitoring (ABPM). However, the determinants of oscillometric PWV in the end-stage kidney disease (ESKD) population remain poorly understood. METHODS: In this study, 81 ESKD patients undergoing long-term peritoneal dialysis underwent 24-h ABPM with the Mobil-O-Graph device. The association of 24-h oscillometric PWV with several demographic, clinical and haemodynamic parameters was explored using linear regression analysis. RESULTS: In univariate analysis, among 21 risk factors, 24-h PWV exhibited a positive relationship with age, body mass index, overhydration assessed via bioimpedance spectroscopy, diabetic status, history of dyslipidaemia and coronary heart disease, and it had a negative relationship with female sex and 24-h heart rate. In stepwise multivariate analysis, age (ß: 0.883), 24-h systolic blood pressure (BP) (ß: 0.217) and 24-h heart rate (ß: -0.083) were the only three factors that remained as independent determinants of 24-h PWV (adjusted R 2 = 0.929). These associations were not modified when all 21 risk factors were analysed conjointly or when the model included only variables shown to be significant in univariate comparisons. CONCLUSION: The present study shows that age together with simultaneously assessed oscillometric BP and heart rate are the major determinants of Mobil-O-Graph-derived PWV, explaining >90% of the total variation of this marker. This age dependence of oscillometric PWV limits the validity of this marker to detect the premature vascular ageing, a unique characteristic of vascular remodelling in ESKD.

A comparative analysis of ambulatory BP profile and arterial stiffness between CAPD and APD.

Prior studies have associated automated peritoneal dialysis (APD) with less effective volume and blood pressure (BP) control as compared with continuous ambulatory peritoneal dialysis (CAPD). Our study aimed to compare the volume status, ambulatory BP profile and severity of arterial stiffness between patients treated with CAPD versus APD. In a case-control design, 28 CAPD patients were matched in 1:1 ratio with 28 controls receiving APD for age, gender and diabetic status. Body composition was assessed with the method of bioimpendence spectroscopy. Twenty-four hours ambulatory BP monitoring with the Mobil-O-Graph device (IEM, Germany) was performed to determine peripheral and central hemodynamic parameters, heart rate-adjusted augmentation index (AIx75) and pulse wave velocity (PWV). Standardized office BP, antihypertensive medication use and extracellular-to-total body water ratio did not differ between CAPD and APD groups. Twenty-four hours brachial systolic BP (129.0 ± 17.3 vs. 128.1 ± 14.2 mmHg, P = 0.83) and 24-h aortic systolic BP (116.9 ± 16.4 vs. 116.4 ± 11.6 mmHg, P = 0.87) were similar in patients treated with CAPD versus APD. Similarly, there was no significant difference between PD modalities in severity of arterial stiffness, as assessed with 24-h AIx75 (24.8 ± 8.9 vs. 22.5 ± 9.1, P = 0.36) and 24-h PWV (9.1 ± 2.4 vs. 8.8 ± 2.1 m/s, P = 0.61). The present study suggests that there is no difference in peripheral and central hemodynamic parameters as well as in the severity of arterial stiffness between CAPD and APD. However, these observations should be interpreted within the context of clinical characteristics of patients included in this case-control study. The comparative effectiveness of these 2 PD modalities warrants further investigation in larger longitudinal studies.

Prevalence of Apparent Treatment-Resistant Hypertension in ESKD Patients Receiving Peritoneal Dialysis.

BACKGROUND: Apparent treatment-resistant hypertension (aTRH) is defined as failure to achieve adequate blood pressure (BP) control despite taking ≥3 antihypertensive medications from different categories or when taking ≥4 antihypertensives regardless of BP levels. METHODS: In this cross-sectional study, we estimated the prevalence of aTRH in 140 patients receiving long-term peritoneal dialysis (PD) in four centers of Northern Greece, using the "gold-standard" method of ambulatory BP monitoring for the assessment of BP control status. The presence of subclinical overhydration was evaluated with the method of bioimpedance spectroscopy (BIS). RESULTS: Incorporating the diagnostic threshold of 130/80 mmHg for 24-hour ambulatory BP, the prevalence of aTRH in the overall study population was 30%. Compared to patients without aTRH, those with aTRH tended to be older in age, had higher PD vintage, had higher dialysate-to-plasma creatinine ratio, had more commonly history of diabetes mellitus, and were more commonly current smokers. With respect to the volume status, the overhydration index in BIS was higher in those with versus without aTRH (2.0 ±â€…1.9 L vs. 1.1 ±â€…2.0 L, P < 0.05). The prevalence of volume overload, defined as an overhydration index in BIS > 2.5 L, was also higher in the subgroup of patients with aTRH (38.1% vs. 18.4, P = 0.01). CONCLUSION: The present study showed that among patients on PD, the prevalence of aTRH was 30%. However, 38% of PD patients with aTRH had subclinical overhydration in BIS, suggesting that the achievement of adequate volume control may be a therapeutic opportunity to improve the management of hypertension in this high-risk patient population.The present study showed that among patients on PD, the prevalence of aTRH was 30%. However, 38% of PD patients with aTRH had subclinical overhydration in BIS, suggesting that the achievement of adequate volume control may be a therapeutic opportunity to improve the management of hypertension in this high-risk patient population. CLINICAL TRIALS REGISTRATION: Trial Number NCT03607747.

Dosimetric accuracy of a deterministic radiation transport based 192Ir brachytherapy treatment planning system. Part II: Monte Carlo and experimental verification of a multiple source dwell position plan employing a shielded applicator.

PURPOSE: The aim of this work is the dosimetric validation of a deterministic radiation transport based treatment planning system (BRACHYVISION v. 8.8, referred to as TPS in the following) for multiple 192Ir source dwell position brachytherapy applications employing a shielded applicator in homogeneous water geometries. METHODS: TPS calculations for an irradiation plan employing seven VS2000 192Ir high dose rate (HDR) source dwell positions and a partially shielded applicator (GM11004380) were compared to corresponding Monte Carlo (MC) simulation results, as well as experimental results obtained using the VIP polymer gel-magnetic resonance imaging three-dimensional dosimetry method with a custom made phantom. RESULTS: TPS and MC dose distributions were found in agreement which is mainly within +/- 2%. Considerable differences between TPS and MC results (greater than 2%) were observed at points in the penumbra of the shields (i.e., close to the edges of the "shielded" segment of the geometries). These differences were experimentally verified and therefore attributed to the TPS. Apart from these regions, experimental and TPS dose distributions were found in agreement within 2 mm distance to agreement and 5% dose difference criteria. As shown in this work, these results mark a significant improvement relative to dosimetry algorithms that disregard the presence of the shielded applicator since the use of the latter leads to dosimetry errors on the order of 20%-30% at the edge of the "unshielded" segment of the geometry and even 2%-6% at points corresponding to the potential location of the target volume in clinical applications using the applicator (points in the unshielded segment at short distances from the applicator). CONCLUSIONS: Results of this work attest the capability of the TPS to accurately account for the scatter conditions and the increased attenuation involved in HDR brachytherapy applications employing multiple source dwell positions and partially shielded applicators.

Evaluation and treatment of a posttraumatic intrahepatic biloma in a dog.

A 9 mo old male mixed-breed dog was presented with a history of chronic vomiting and fever after undergoing a cholecystectomy for the management of traumatic cystic duct rupture associated with biliary effusion 10 days before referral. A 6 cm × 6 cm intrahepatic bile collection, a biloma, was diagnosed on abdominal ultrasound and fine-needle aspiration. The biloma was treated with percutaneous catheter drainage under ultrasonographic guidance. Two years after aspiration, the dog continued to do well.