Left Atrial Appendage Closure in Patients With a Mechanical Mitral Valve Prosthesis: A Multicentre Italian Pilot Study

BACKGROUND

In patients with atrial fibrillation (AF) on vitamin K antagonist (VKA) therapy and therapeutic international normalized ratio (INR) range, the incidence of cardiac thromboembolism is not negligible, and the subgroup of patients who have a mechanical prosthetic mitral valve (PMV) has the highest risk. We aimed to assess the long-term effects of left atrial appendage closure (LAAC) in AF patients with a mechanical PMV who experienced a failure of VKA therapy.

METHODS

In this retrospective, multicentre study, patients underwent LAAC because of thrombotic events including transient ischemic attack and/or stroke, systemic embolism, and evidence of left atrial appendage thrombosis and/or sludge, despite VKA therapy, were enrolled. Patients with a mechanical PMV were included and compared with those affected by nonvalvular AF. The primary endpoint was the composite of all-cause death, major cardiovascular events, and major bleedings at follow-up. The feasibility and safety of LAAC also were assessed.

RESULTS

A total of 55 patients (42% female; mean age, 70 ± 9 years), including 12 with a mechanical PMV, were enrolled. The most-frequent indication to LAAC (71%) was LAA thrombosis or sludge. Procedural success was achieved in 96% of overall cases, and in 100% of patients with a PMV. In 35 patients, a cerebral protection device was used. During a median follow-up of 6.1 ± 4.3 years, 4 patients with a PMV, and 20 patients without a PMV, reported adverse events (hazard ratio 0.73 [95% confidence interval 0.25-2.16, P = 0.564]).

CONCLUSIONS

LAAC seems to be a valuable alternative in patients with AF who have a mechanical PMV, with failure of VKA therapy. This off-label, real-world clinical practice indication deserves validation in further studies.

Subacute postoperative atrial fibrillation after heart surgery: Incidence and predictive factors in cardiac rehabilitation

Background

Postoperative atrial fibrillation (POAF) is the most common arrhythmia following cardiac surgery (CS). It may occur between the 1st and the 4th postoperative day as acute POAF or between the 5th and the 30th as subacute (sPOAF). sPOAF is associated with higher thromboembolic risk, which consistently increase patients' morbidity. Neutrophil-to-lymphocyte ratio (NLR) is a low-cost inflammatory index proposed as possible POAF predictor. Identification of patients' risk categories might lead to improved postoperative outcomes.

Methods

The aim was to assess the incidence of sPOAF and to identify possible predictors in patients performing cardiovascular rehabilitation (CR) after CS. A single-center cohort study was performed on 737 post-surgical patients admitted to CR on sinus rhythm. Continuous monitoring with 12-lead ECG telemetry was performed. We evaluated the predictive role of anamnestic, clinical, and laboratory data, including baseline NLR.

Results

Subacute POAF was documented in 170 cases (23.1%). At the multivariate analysis, age (OR 1.03; p = .001), mitral valve surgery (OR 1.77; p = .012), acute POAF (OR 2.97; p < .001), and NLR at baseline (OR 1.13; p = .042) were found to be independent predictive factors of sPOAF following heart surgery.

Conclusions

sPOAF is common after CS. Age, mitral valve procedures, acute POAF, and preoperative NLR were proved to increase sPOAF occurrence in CR. NLR is an affordable and reliable parameter which might be used to qualify the risk of arrhythmias at CR admission. Identification of new predictors of postoperative atrial fibrillation may allow to improve patients' prognosis.

Imaging of the Diaphragm Following Cardiac Surgery: Focus on Ultrasonographic Assessment

Diaphragm dysfunction is a common complication following cardiac surgery. Its clinical impact is variable, ranging from the absence of symptoms to the acute respiratory failure. Post-operative diaphragm dysfunction may negatively affect patients' prognosis delaying the weaning from the mechanical ventilation (MV), extending the time of hospitalization and increasing mortality. Ultrasonography is a valid tool to evaluate diaphragmatic impairment in different settings, like the Intensive Care Unit, to predict successful weaning from the MV, and the Cardiovascular Rehabilitation Unit, to stratify patients in terms of risk of functional recovery failure. The aim of this review is to describe the pathophysiology of post-cardiac surgery diaphragm dysfunction, the techniques used for its diagnosis and the potential applications of diaphragm ultrasound.

Accuracy and Reliability of Left Atrial Appendage Morphology Assessment by Three-Dimensional Transesophageal Echocardiographic Glass Rendering Modality: A Comparative Study With Computed Tomography

BACKGROUND

Contrast-enhanced computed tomography is the reference-standard imaging technique to assess left atrial appendage (LAA) morphology. The aim of this study was to evaluate the accuracy and reliability of two-dimensional and new three-dimensional (3D) transesophageal echocardiographic rendering modalities in assessing LAA morphology.

METHODS

Seventy consecutive patients who underwent both computed tomography and transesophageal echocardiography (TEE) were retrospectively enrolled. The traditional LAA morphology classification system (LAAcs; chicken wing, cauliflower, cactus, and windsock) and a new simplified LAAcs based on the LAA bend angle were used for the analysis. LAA morphology was independently assessed by two trained readers using three different modalities: two-dimensional TEE, 3D TEE with multiplanar reconstruction, and a new 3D transesophageal echocardiographic rendering modality with improved transparency (Glass). The new LAAcs and traditional LAAcs were compared in terms of intra- and interrater reliability.

RESULTS

With the new LAAcs, two-dimensional TEE was fairly accurate in identifying LAA morphology (κ = 0.43, P < .05), with moderate interrater (κ = 0.50, P < .05) and substantial intrarater (κ = 0.65, P < .005) agreement. Three-dimensional TEE showed higher accuracy and reliability: 3D TEE with multiplanar reconstruction had almost perfect accuracy (κ = 0.85, P < .001) and substantial (κ = 0.79, P < .001) interrater reliability, while 3D TEE with Glass had substantial accuracy (κ = 0.70, P < .001) and almost perfect (κ = 0.84, P < .001) interrater reliability. Intrarater agreement was almost perfect for both 3D transesophageal echocardiographic modalities (κ = 0.85, P < .001). Accuracy was considerably lower when the traditional LAAcs was used, with 3D TEE with Glass being the most reliable technique (κ = 0.75, P < .05). The new LAAcs showed higher inter- and intrarater reliability compared with the traditional LAAcs (interrater, κ = 0.85 vs κ = 0.49; intrarater, κ = 0.94 vs κ = 0.68; P < .05).

CONCLUSIONS

Three-dimensional TEE is an accurate, reliable, and feasible alternative to computed tomography in assessing LAA morphology with the new LAAcs. The new LAAcs shows higher reliability rates than the traditional one.

Left atrial appendage occlusion in the absence of intraprocedural product specialist monitoring: is it time to proceed alone? Results from a multicenter real-world experience

Background

Percutaneous left atrial appendage occlusion (LAAO) presents many technical complex features, and it is often performed under the intraprocedural surveillance of a product specialist (PS). Our aim is to assess whether LAAO is equally safe and effective when performed in high-volume centers without PS support.

Methods

Intraprocedural results and long-term outcome were retrospectively assessed in 247 patients who underwent LAAO without intraprocedural PS monitoring between January 2013 and January 2022 at three different hospitals. This cohort was then matched to a population who underwent LAAO with PS surveillance. The primary end point was all-cause mortality at 1 year. The secondary end point was a composite of cardiovascular mortality plus nonfatal ischemic stroke occurrence at 1 year.

Results

Of the 247 study patients, procedural success was achieved in 243 patients (98.4%), with only 1 (0.4%) intraprocedural death. After matching, we did not identify any significant difference between the two groups in terms of procedural time (70 ± 19 min vs. 81 ± 30 min, p = 0.106), procedural success (98.4% vs. 96.7%, p = 0.242), and procedure-related ischemic stroke (0.8% vs. 1.2%, p = 0.653). Compared to the matched cohort, a significant higher dosage of contrast was used during procedures without specialist supervision (98 ± 19 vs. 43 ± 21, p < 0.001), but this was not associated with a higher postprocedural acute kidney injury occurrence (0.8% vs. 0.4%, p = 0.56). At 1 year, the primary and the secondary endpoints occurred in 21 (9%) and 11 (4%) of our cohort, respectively. Kaplan-Meier curves showed no significant difference in both primary (p = 0.85) and secondary (p = 0.74) endpoint occurrence according to intraprocedural PS monitoring.

Conclusions

Our results show that LAAO, despite the absence of intraprocedural PS monitoring, remains a long-term safe and effective procedure, when performed in high-volume centers.

Left atrial appendage occlusion after thromboembolic events or left atrial appendage sludge during anticoagulation therapy: Is two better than one? Real-world experience from a tertiary care hospital

BACKGROUND

The role of left atrial appendage occlusion (LAAO) for atrial fibrillation patients that during oral anticoagulant therapy (OAC) suffer from ischemic events or present LAA sludge, and the best postinterventional anticoagulant regimen, need to be defined. We present our experience with a hybrid approach of LAAO+ lifelong OAC therapy in this cohort of patients.

METHODS

Out of 425 patients treated with LAAO, 102 underwent LAAO because, despite OAC, suffered from ischemic events or presented with LAA sludge. Patients without high bleeding risk were discharged with the aim of maintaining lifelong OAC. This cohort was then matched to a population who underwent LAAO in primary ischemic events prevention. The primary endpoint was the composite of all-cause death and major adverse cardiovascular events consisting of ischemic stroke, systemic embolism (SE), and major bleeding.

RESULTS

Procedural success was 98%, and 70% of patients were discharged with anticoagulant therapy. After a median follow-up of 47.2 months, the primary endpoint occurred in 27 patients (26%). At multivariate analyses, coronary artery disease (OR 5.1, CI 1.89-14.27, p = .003) and OAC at discharge (OR 0.29, CI 0.11-0.80, p = .017) were associated with the primary endpoint. After propensity score matching, no significant difference was found in the survival free from the primary endpoint according to the indication for LAAO (p = .19).

CONCLUSIONS

In this high-ischemic risk cohort, LAAO + OAC seem a long-term safe and effective therapeutical approach, with no difference in the survival free from the primary endpoint according to the indication for LAAO in a matched cohort.

250 POST-PERICARDIOTOMY SINDROME: A DESCRIPTIVE ANALYSIS OF A NEGLECTED SYNDROME

Background

Post-pericardiotomy syndrome (PPS) is a condition in which the surgical incision of the pericardium provokes the onset of pericardial and/or pleural effusion as a result of the inflammatory response inside the pericardial and/or the pleural space. PPS is a common complication following cardiac surgery (CS) and it has a significant impact on post-surgical patients’ management. Thus, it would be useful to find predictors in order to stratify patients in terms of risk of PPS and define tailored Cardiovascular Rehabilitation (CR) programmes.

Purpose

The aim of this study was to assess the incidence and to elucidate the features of PPS in a population of patients undergoing cardiac surgery. Secondly, the study was focused on the findings of likeable predictors of PPS and PPS’ relapse.

Methods

A prospective cohort study was performed on 156 patients who underwent cardiac surgery and then were admitted to the CR Unit of our institute. Among the 156-patients population, 26 patients developed post-pericardiotomy syndrome. Pre-operative and post-operative anamnestic and clinical data were collected to define the baseline characteristics of the population. The predictive role of anamnestic data, type of surgical procedure and laboratory parameters was evaluated. Treatment was then started in the PPS population, analysed and compared to the outcome. Data were collected during CR hospital stay and after discharge, during follow up check-ups. During CR hospital stay, the analysis regarded first and second line medical therapy, which was started in case of persistence, worsening or relapse of the pericardial and/or pleural effusion. After discharge, the analysis considered the outcome of the therapy at a defined deadline. Binary logistic regression analysis was performed to identify possible predictors of PPS and PPS’ relapse. All the variables with a univariate p-value &lt;0.150 or clinically relevant were entered into the multivariate model.

Results

The population comprehends 156 patients. PPS patients presented with pleural effusion pre surgical intervention in 3 cases (11.5% vs 0%; p-value &lt; 0.001) and showed more frequently pericardial effusion early after surgery (53.8% vs 8.5%; p-value &lt; 0.001). In 3 patients (1.9%) drainage of pleural effusion was needed (7.7% vs 0.8%, p-value= 0.019). At admission in the CR Unit 26 patients (16.6%) presented or subsequently developed PPS. Pericardial effusion was classified as mild in 18 patients (69.2%), moderate in 7 patients (26.9%) and severe in 1 patient (3.8%); the median value of pericardial effusion at diagnosis was 7.5 mm, while the median value of the maximum pericardial effusion was 9.5 mm. During in-hospital stay, a first line medical therapy was administered to 26 PPS patients (100%): 13 patients (50%) needed a switch to a second line therapy, 4 patients (15.4%) needed invasive treatment of the effusion, 3 patients (11.5%) needed percutaneous pleural drainage and 2 patients (7.7%) needed percutaneous pericardial drainage. Medical therapy’ collateral effects occurred in 7 patients (26.95%). PPS therapy at discharge was administered to 22 patients (84.6%). At follow up, pericardial effusion occurred in 9 patients (36%), pleural effusion occurred in 3 patients (12%). Relapse of pleuro/pericardial effusion after therapy suspension occurred in 3 patients (12%) and consequently, pleuro/pericardial effusion resolution was obtained in 23 patients (92%). The median time of therapy interruption at follow up was 27 days (7–60). Binary logistic regression was performed to identify the clinical predictors of PPS and PPS’ relapse, the multivariate analysis did not find statistical significance for independent predictors of both conditions.

Conclusion

The PPS is a common complication of cardiac surgery. Further studies are needed to determine novel possible PPS predictors. Possible indicators of PPS relapse should be identified in patients with possible discontinuation of treatment.

68 LEFT ATRIAL APPENDAGE OCCLUSION AFTER THROMBOEMBOLIC EVENTS OR LEFT ATRIAL APPENDAGE SLUDGE DURING ANTICOAGULATION THERAPY: TWO IS BETTER THAN ONE. REAL-WORLD EXPERIENCE FROM A TERIARY CARE CENTER

Background

Although, in recent years, the indications for left atrial appendage occlusion (LAAO) have expanded, its role for patients that during oral anticoagulant (OAC) therapy suffer from ischemic events or present LAA sludge is still to be defined. Moreover, data on the best anticoagulant regiment post-LAAO for these patients is scarce.

Purpose

Aim of this study was to present our experience with a hybrid approach consisting of LAAO+ lifelong OAC therapy in this cohort of high-ischemic risk patients.

Methods

At our center, from January 2013 to June 2022, 102 patients underwent percutaneous LAAO because, despite optimal OAC, suffered from ischemic events or were found to have LAA sludge. In the absence of a high bleeding risk, patients were then discharged with the aim of maintaining lifelong OAC. Moreover, to confirm the feasibility and the long-term efficacy of LAAO in this cohort, the group was matched 1:1 to a patient population who underwent LAAO in our center to prevent ischemic events and without sludge at preprocedural TEE. The primary endpoint was the composite of all-cause death (ACD) and major adverse cardiovascular events (MACE) consisting of ischemic stroke, systemic embolism (SE) and major bleeding

Results

Procedural success was achieved in 98% of patients. 70% of patients were discharged with anticoagulant therapy, while 30% only with antiplatelet therapy. After a median follow-up of 47.2 months, none of the patients discharged with OAC had stroke, SE or device-related thrombosis. The primary composite endpoint of ACD+ MACE occurred in 27 patients (26%). Patients affected by the primary outcome had more history of coronary artery disease (CAD, p&lt;0.001), diabetes mellitus (DM p=0.003), left ventricular systolic dysfunction (LVSD, p=0.004) and were more often discharged without OAC (p=0.005) compared to those who weren't. After univariate and multivariate analyses, CAD (OR 5.1, CI 1.89- 14.27, p=0.003) and OAC at discharge (OR 0.29, CI 0.11- 0.80, p=0.017) were independently associated with the primary endpoint. At survival analyses, there was a constant trend toward a longer survival free from the primary composite endpoint for patients discharged in anticoagulant therapy compared to those without, but not reaching statistical significance (p=0.41). Finally, after propensity score matching, Kaplan Meyer curves showed that there was no significant difference in the long-term survival free from the primary composite EP according to the indication for LAAO (p=0.19).

Conclusions

We report our experience on the management of patients with ischemic events or LAA sludge despite OAC. Percutaneous LAAO was feasible with a high procedural success. Our hybrid therapeutical approach consisting of LAAO+ lifelong OAC, if feasible in the absence of high bleeding risk, was safety and effective in reducing clinical ischemic events after a long-term follow-up.

Diaphragm Dysfunction after Cardiac Surgery: Insights from Ultrasound Imaging during Cardiac Rehabilitation

Diaphragm dysfunction is common after cardiac surgery and can be evaluated with ultrasonography (US). We aimed at assessing with US the incidence of diaphragmatic dysfunction and the impact of cardiovascular rehabilitation (CR) on its recovery. A single-center cohort study was performed. Patients were enrolled after cardiac surgery. The 6-min walking test (6MWT) and diaphragm US were performed at CR admission and after 10 rehabilitative sessions. One hundred eighty-five patients were eligible for final analysis. One hundred thirty-one patients (70.8%) were found to have diaphragm dysfunction (excursion <2 cm). After CR, 68 patients regained normal diaphragmatic function; those with persistent dysfunction had a lower level of functional performance on the 6MWT (metabolic equivalents of tasks: 3.3 vs. 3.6, p = 0.013). The patients who underwent combined surgery (adjusted odds ratio [aOR] = 4.09, p = 0.001) and those with post-operative pneumothorax (aOR = 3.02, p = 0.042) were at increased risk of failure to improve diaphragmatic excursion. US parameters were more powerful tools in predicting diaphragmatic evolution compared with the 6MWT indexes: baseline diaphragm excursion and thickening fraction were associated with complete diaphragmatic functional recovery after CR (aOR = 9.101, p < 0.001, and aOR = 1.058, p = 0.020 respectively). US is a valuable tool for the assessment of post-operative diaphragmatic dysfunction and can identify patients at risk of diaphragmatic recovery failure.

Subacute postoperative atrial fibrillation after heart surgery: incidence and predictive factors in cardiac rehabilitation

Funding Acknowledgements

Type of funding sources: None.

Background. Postoperative atrial fibrillation (POAF) is the most common arrhythmic complication following cardiac surgery. It may occur between the second and fourth postoperative days as acute POAF, or within 30 days as subacute POAF (sPOAF). The incidence varies from 15% to 60%, with the highest rates observed in patients undergoing valvular surgery. POAF is associated with longer hospital stay and higher thromboembolic risk, which consistently increase patients’ morbidity and mortality. Identification of high-risk categories may allow optimization of in-hospital prevention and treatment, possibly improving clinical outcomes.

Aim of the study. The aim of this study was to assess the incidence of sPOAF and to identify possible predictors in patients performing Cardiovascular Rehabilitation (CR) after Cardiac Surgery (CS).

Methods. A single-centre retrospective study was performed on 383 post-cardiac surgery patients hospitalised in our CR Unit for inpatient rehabilitation. The entire population was on sinus rhythm at the admission in CR and continuous monitoring with 12-lead ECG telemetry was performed during the hospital stay. We calculated the incidence of sPOAF and then evaluated the predictive value of the following variables: anamnestic data, type of cardiac intervention, clinical course in both CS and CR Unit, laboratory parameters including baseline neutrophil-to-lymphocyte ratio (NLR).

Results. Median age was 65 years (63% male). sPOAF was documented in 122 cases (31.9%). Patients developing sPOAF were older [median age 69 (63-76) vs. 61 (51-70); p &lt; 0.001)], more frequently underwent complex surgical procedures (50% vs. 36%; p = 0.009) and were known for previous episodes of atrial fibrillation (27.9% vs. 11.2%; p &lt; 0.001). On the first day after surgery (T1), sPOAF group showed higher values of glycemia [median 155 (126.5–186.8) vs. 129 (106.5–164); p &lt; 0.001] and troponin T [median 721.5 (470.1–1084.3) vs. 488 (301.6-776.2); p &lt; 0.001]. The multivariate analysis identified advanced age (OR 1.04, 95% CI 1.01-1.08; p = 0.023), acute POAF in the Cardiac Surgery Unit (OR 3.51, 95% CI 1.62-7.59; p = 0.001), baseline NLR (OR 1.46, 95% CI 1.10-1.93; p = 0.008) and T1-troponin &gt; 552 ng/L (OR 4.16 95% CI 1.50-11.53; p = 0.006) as independent risk predictors of sPOAF during the CR period.

Conclusions. sPOAF is common after cardiac surgery occurring in 31.9% of patients during CR. Age, acute POAF, baseline NLR and elevated troponin T on the first postoperative day were shown predictors of increased sPOAF risk. Recognition of new predictors of POAF could be helpful to better stratify patients, improving management strategies and outcomes.

Cardiovascular rehabilitation after valvular heart surgery: predictive factors of major complications

Background

The population of patients affected by valvular heart disease is growing and for many of them valvular surgery is still considered the gold standard treatment. Cardiovascular Rehabilitation (CR) following intervention is fundamental for the post-surgical functional recovery and for the monitoring and management of complications that may occur after surgery.

Aim of the study

We aimed at identifying predictors of major complications in patients who underwent valvular surgery and subsequently were involved in an in-patient CR program. Major complications were defined as those requiring an in-patient management: severe anemia needing transfusions, infection of the sternal surgical wound requiring an antibiotic treatment, a positive hemoculture in the presence of systemic signs of infection and pericardial effusion requiring surgical drainage.

Methods and statistical analysis

1600 patients who have been hospitalized in our CR Unit after valvular surgery were enrolled (median age 64 years; 60% males). We examined the demographic data, the cardiovascular risk factors, the main comorbidities, the type of heart surgery (type of valvular surgery and the presence of concomitant other cardiac intervention), the complications developed in Cardiac Surgery Unit and in the CR Unit, the in-hospital length of stay, the 6 minutes-walking tests and principal blood tests.

Results

At multivariate analysis we found that chronic renal dysfunction [OR 1,902 (CI 1,103–3,280), p=0,021], complex cardiac intervention [OR 1,554 (CI 1,030–2,344), p=0,036], sternal re-synthesis [OR 4,671 (CI 1,659–13,152), p=0,004], early post-surgical transfusions [OR 1,670 (CI 1,083–2,573), p=0,020] are independent risk factors for major complications, while a higher hemoglobin value at CR admission [OR 0,677 (CI 0,566–0,810), p&lt;0,001] resulted an independent protective factor.

Conclusions

We identified predictors of major complications during CR after valvular surgery. These factors may help in defining the patients at major risk tailoring the patient management, adopting an individualized clinical and instrumental monitoring. A tailored CR period gives the possibility to optimize the use of hospital economic resources and to achieve a better final outcome.

Funding Acknowledgement

Type of funding source: None

Subacute post-operative atrial fibrillation after valvular surgery in patients undergoing cardiac rehabilitation: predictive factors

Background

Postoperative atrial fibrillation (POAF) is the most frequent arrhythmic complication following cardiac surgery (occurring in up to one third of patients). It may develop between the second and fourth postoperative days (acute POAF) as well as later, within 30 days after surgery (subacute). Episodes of atrial fibrillation in the subacute phase (sPOAF) are associated with an increase in morbidity, length of hospital stay and several complications both in the mid- and long- term. Therefore, POAF is not just an acute event but it may impact on long term clinical outcomes.

Aim of the study

The aim of this study was to identify the clinical predictors of postoperative atrial fibrillation in the subacute phase (sPOAF) in patients performing Cardiovascular Rehabilitation (CR) after cardiac surgery.

Materials and methods

A retrospective study was conducted on 737 post-surgical valvular patients (median age 62 years; 55,4% male) hospitalised in our Unit for in-patient CR program. During all the hospital stay patients received continuous monitoring with 12-lead ECG telemetry. We evaluated the predictive value of anamnestic data, the type of cardiac surgery intervention, the clinical course in the Cardiac Surgery Unit and in the CR Unit, the 6 minutes-walking tests (6MWT) parameters and main blood tests on sPOAF onset.

Results

SPOAF was documented in 170 patients (23,1%). Those who developed sPOAF were older [median 66 (56–74) years vs median 61 (50–70) years; p&lt;0,001), had a history of atrial fibrillation prior to surgery (29,4% vs 16,2%; p&lt;0,001), had a worse functional result at the 6MWT at the admission in CR Unit [median 250 (180–320) vs median 275 (210–370); p=0,015], had higher values of neutrophil-lymphocite ratio at baseline [median 2,33 (1,84–3,27) vs median 2,17 (1,64 - 2,87); p=0,027] when compared to those who did not develop POAF. At the multivariable logistic regression analysis, the occurrence of POAF in the acute phase (OR 2,916; 95% CI 2,011–4,228; p&lt;0,001), advanced age (OR 1,027; 95% CI 1,01–1,044; p=0,002), previous history of atrial fibrillation (OR 1,652; 95% CI 1,068–2,555; p=0,024), higher values of NLR at baseline (OR 1,144; 95% CI 1,028–1,272; p=0,013) and mitral valve surgery (OR 1,632, 95% CI 1,075–2,480; p=0,022) were found to be independent predictors of sPOAF after cardiac surgery.

Conclusions

Atrial fibrillation is a common complication after cardiac surgery with great clinical relevance. Advanced age, previous history of AF, higher values of NLR at baseline, mitral valve surgery and the occurrence of POAF in the acute phase were shown to be predictors of sPOAF in a cardiac surgery population during the rehabilitation period.

Funding Acknowledgement

Type of funding source: None

Estimated health impacts from maritime transport in the Mediterranean region and benefits from the use of cleaner fuels

Ship traffic emissions degrade air quality in coastal areas and contribute to climate impacts globally. The estimated health burden of exposure to shipping emissions in coastal areas may inform policy makers as they seek to reduce exposure and associated potential health impacts. This work estimates the PM2.5-attributable impacts in the form of premature mortality and cardiovascular and respiratory hospital admissions, from long-term exposure to shipping emissions. Health impact assessment (HIA) was performed in 8 Mediterranean coastal cities, using a baseline conditions from the literature and a policy case accounting for the MARPOL Annex VI rules requiring cleaner fuels in 2020. Input data were (a) shipping contributions to ambient PM2.5 concentrations based on receptor modelling studies found in the literature, (b) population and health incidence data from national statistical registries, and (c) geographically-relevant concentration-response functions from the literature. Long-term exposure to ship-sourced PM2.5 accounted for 430 (95% CI: 220-650) premature deaths per year, in the 8 cities, distributed between groups of cities: Barcelona and Athens, with >100 premature deaths/year, and Nicosia, Brindisi, Genoa, Venice, Msida and Melilla, with tens of premature deaths/year. The more stringent standards in 2020 would reduce the number of PM2.5-attributable premature deaths by 15% on average. HIA provided a comparative assessment of the health burden of shipping emissions across Mediterranean coastal cities, which may provide decision support for urban planning with a special focus on harbour areas, and in view of the reduction in sulphur content of marine fuels due to MARPOL Annex VI in 2020.

A novel approach to evaluate the lung cancer risk of airborne particles emitted in a city

Air quality still represents a main threat to human health in cities. Even in developed countries, decades of air pollution control not yet allowed to reduce pollutant concentrations in urban areas adequately. Indeed, high airborne particle concentrations are measured in several European cities; this is a main issue since particles represent a carrier for carcinogenic compounds. Numerous researches measuring the exposure to the different aerosol metrics in urban areas were recently performed, nonetheless, few data on the lung cancer risk in such environments are available. In the present paper a novel approach to evaluate the lung cancer risk related to the airborne particles emitted by the different sources located in a city is proposed and applied to a pilot case-study (i.e. an Italian city). In particular, an existing lung cancer risk model was modified and applied to assess the particle-related lung cancer "emitted" by the different sources of the city using pollutant emission factors provided by accredited emission inventory databases. Therefore, the average toxicity of the particles emitted by the city (i.e. lung cancer slope factor) and the lung cancer risk globally emitted by the city, expressed as new cases of lung cancer, were evaluated. The proposed emission inventory also allowed to identify and localize the main contributors to the overall risk emitted in a city. As an example, for the city under investigation, the research revealed that the main contributor, amongst the sources considered, is the vehicular traffic which is characterized by a lower mass fraction of carcinogenic compounds but a much higher sub-micron particle emission with respect to the other sources.

Characterization of airborne particles emitted by an electrically heated tobacco smoking system

Smoking activities were recognized as a main risk factor for population. Indeed, mainstream smoke aerosol is directly inhaled by smokers then delivering harmful compounds in the deepest regions of the lung. In order to reduce the potential risk of smoking, different nicotine delivery products have been recently developed. The latest device released is an electrically heated tobacco system (iQOS®, Philip Morris) which is able to warm the tobacco with no combustion. In the present paper a dimensional and volatility characterization of iQOS-generated particles was performed through particle number concentration and distribution measurements in the mainstream aerosol. The experimental analysis was carried out through a condensation particle counter, a fast mobility particle sizer and a thermo-dilution sampling system allowing aerosol samplings at different temperatures. Estimates of the particle surface area dose received by smokers were also carried out on the basis of measured data and typical smoking patterns. The particle number concentrations in the mainstream aerosols resulted lower than 1 × 108 part. cm-3 with particle number distribution modes of about 100 nm. Nonetheless, the volatility analysis showed the high amount of volatile fraction of iQOS-generated particles, indeed, samplings performed at 300 °C confirmed a significant particle shrinking phenomena (modes of about 20 nm). Anyway, the particle number concentration does not statistically decrease at higher sampling temperatures, then showing that a non-volatile fraction is always presents in the emitted particles. The dose received by smokers in terms of non-volatile amount of particle surface area was equal to 1-2 mm2 per puff, i.e. up to 4-fold larger than that received by electronic cigarette vapers.

Lung cancer risk assessment due to traffic-generated particles exposure in urban street canyons: A numerical modelling approach

Combustion-generated nanoparticles are responsible for negative health effects due to their ability to penetrate in the lungs, carrying toxic compounds with them. In urban areas, the coexistence of nanoparticle sources and particular street-building configurations can lead to very high particle exposure levels. In the present paper, an innovative approach for the evaluation of lung cancer incidence in street canyon due to exposure to traffic-generated particles was proposed. To this end, the literature-available values of particulate matter, PAHs and heavy metals emitted from different kind of vehicles were used to calculate the Excess Lifetime Cancer Risk (ELCR) at the tailpipe. The estimated ELCR was then used as input data in a numerical CFD (Computational Fluid Dynamics) model that solves the mass, momentum, turbulence and species transport equations, in order to evaluate the cancer risk in every point of interest inside the street canyon. Thus, the influence of wind speed and street canyon geometry (H/W, height of building, H and width of the street, W) on the ELCR at street level was evaluated by means of a CFD simulation. It was found that the ELCR calculated on the leeward and windward sides of the street canyon at a breathable height of 1.5 m, for people exposed 15 min per day for 20 years, is equal to 1.5 × 10^-5 and 4.8 × 10^-6, respectively, for wind speed of 1 m/s and H/W equal to 1. The ELCR at street level results higher on the leeward side for aspect ratios equal to 1 and 3, while for aspect ratio equal to 2 it is higher on the windward side. In addition, the simulations showed that with the increasing of wind speed the ELCR becomes lower everywhere in the street canyon, due to the increased in dispersion.

Blood Volume Modeling and Refilling Rate Estimation in Hemodialysis by Continuous Hemoglobin Monitoring

Eleven bicarbonate hemodialyses (HD) of 6 patients under constant ultrafiltration were continuously monitored with an optical Hb-meter, considered to be a marker of blood volume (BV) changes. A theoretical model was fed experimental data for prediction of blood volume and estimation of vascular parameters, and a time course of rate of refilling was extrapolated. The adequacy of the model was very good for the time course of BV prediction (r2=0.85-0.95, n=11) and for plasma protein concentration (r2=0.83-0.86, n=2). Parameters estimated included (mean-DS): filtration coefficient (Cf)=0.22 (0.16) dl/min∗mmHg, transcapillary hydrostatic pressure (DP)=17.80 (3.44) mmHg and protein concentration of the refilling fluid (Cref)=0.45 (0.30) g/dl. In conclusion our study has shown that the model chosen fits the observed BV profile well in all cases, thus the Hb data series can be used for BV dynamic modeling and for estimation of vascular parameters.

Biochemical Aspects and Clinical Perspectives of Continuous Urea Monitoring in Plasma Ultrafiltrate: Preliminary Results of a Multicenter Study

We tested a new biosensor for urea monitoring in the ultrafiltrate during PFD in a group of 5 hemodialyzed stable patients. The inspection of the UF-urea profile reflects the dynamical changes of the plasma urea concentration during diffusive dialysis and allows the fitting of the main mathematical models of urea kinetics. The biosensor efficiency was 98.4% on average (SD: 1.5%) at Uf fluxes varying from 45 to 55 ml/min (mean: 51 ml/min; SD: 3.2) and at Uf-urea concentrations varying from 23 to 165 mg/dl. The mean difference between Uf-urea determined by the laboratory method and Uf-urea assayed by the biosensor was -1.07 mg/dl and the 95% confidence interval ranged from -2.01 to 0.13 mg/dl. The mean difference between laboratory plasma urea and Uf-urea from the biosensor was on average -1.9 mg/dl and the estimated limits of agreement with a confidence of 95% were -3.16 and 0.64 mg/dl. Comparison between kinetic models and experimental profiles of plasma urea decrease, evaluations of recirculation and post-dialytic rebound, the role of Kt/V on-line during dialysis were the preliminary clinical applications of this biosensor.

Omics as a potential tool to identify biomarkers and to clarify the mechanism of chronic pain development

Aims

The present study aims to identify the underlying mechanisms in the acute to chronic pain transition. Acute pain is a physiological response to an experience of noxious stimuli that can progress to chronic, becoming a disease. The negative consequences as personal suffering, reduction in physical function, maladaptive behaviours, reduction of productivity, make this condition a central and common problem affecting individuals and the society. After an acute damage, pain in some cases persists, being the process attributed to different causes, in particular persistent tissue and neuronal damages, central neuroplastic changes, psychosocial factors.

Methods

The techniques actually used to investigate acute and chronic pain offer only a partial explanation of the process and in addition, the obtained results are often far away from the possibility to lead some benefits in the clinical practice. Omics technologies could be the right way to detect biomarkers explaining these mechanisms. Our previous study examined epigenetic and pharmacogenetic aspects of acute and chronic pain in a large group of patients. Other omic approaches, such as metabolomics and glycomics, could help to (1) better identify metabolites that can serve as chronic pain development or side effects therapy biomarkers and to (2) better understand new insights involved into the pathophysiological mechanism that drives from acute to chronic pain. SNPs, DNA methylation, miRNA analyses, expression and protein assays on the identified pathway would than clarify the causative molecular mechanisms. In addition, linking these results to clinical evaluation of the central sensitization processes through algometry in nociceptive and neuropathic pain patients may reveal crucial clinical and pharmacological implications.

Conclusions

Our project will be implemented by omic technologies in different chronic pain patient cohorts (acute low back pain vs chronic low back pain patients and chronic postsurgical pain patients) in order to evaluate new possible pathophysiological mechanism with special focus in central sensitization.

Variability of airborne particle metrics in an urban area

In the present study a mobile monitoring approach (i.e. bike with onboard instruments) was proposed and applied to investigate the spatial variability of all the key airborne particle metrics in an Italian urban area from a statistical point of view. Particle number, alveolar-deposited surface area, and PM₁₀ concentrations were measured through hand-held monitors and compared to simultaneous background concentrations by means of non-parametric tests and further post-hoc tests (Kruskal-Wallis test). Streets characterized by exposure levels statistically higher than the background levels for all the particle metrics were identified for different seasons in a pilot urban area (Cassino, Italy). A higher number of hot spots was detected for metrics affected by ultrafine particles (i.e. number and alveolar-deposited surface area concentrations) with respect to PM₁₀. The effect of metrological requirements of the instrumentation on the proposed method was also discussed.

Management of kidney transplantation in a factor VII-deficient patient: case report

Transplantation in patients with congenital bleeding disorders is a challenge requiring an integrated approach of various specialists. Renal transplantation, the most frequent type of solid organ transplantation, is rarely performed in individuals with congenital hemorrhagic disorders. We performed a renal transplantation in a 53-year-old man with end-stage renal disease and congenital coagulation factor VII deficiency, a rare bleeding disorder with a peculiar clinical picture requiring replacement therapy in surgical interventions. Perioperative bleeding was successfully prevented by administration of recombinant activated factor VII. Treatment schedule, administration rate, and long-term follow-up are reported in detail. Our report confirmed the feasibility and safety of recombinant activated factor VII in major surgical procedures like solid organ transplantations. Success requires evaluation of doses and therapeutic schedules as well as a multidisciplinary approach.

Kidney transplantation from older donors

BACKGROUND

The use of kidneys from older donors has become generally accepted and increasingly common, despite the knowledge that donor age is a well-known risk factor for graft failure.

AIM

To review our experience with the utilization of kidneys from donors older than 60 years.

PATIENTS AND METHODS

Among two hundred eight patients, 32 (group A) received an organ obtained from a donor older than 60 years. The organs were age-matched with a maximum gap of 20 years between donors and recipients. Organs from older donors were assigned to recipients presenting a body mass index lower than that of the donor. The primary end point was patient and graft survival. Secondary endpoints were incidences of delayed graft function and of acute rejection episodes as well as renal function at 3 months and yearly.

RESULTS

The two groups were comparable in terms of demographic features, indications for transplantation, comorbidities, as well as cold and warm ischemia times. The Mean lengths of follow up were 31.4 ± 20.3 months and 30.3 ± 20.1 months, respectively. Graft and patient survivals were comparable. Mean creatinine values at the study intervals were significantly lower among group B who received grafts from younger donors. The incidence of delayed graft function and acute rejection episodes were similar: 15.6% (5/32) versus 20.5% (36/176; P=0.35) and 15.6% (5/32) and 12.1% (21/167; P=0.136) in groups A and B, respectively.

CONCLUSIONS

Donor age older than 60 years showed a negative impact on kidney function. Though, given the escalating disparity between organ supply and demand, this precious source of organs cannot be neglected. We need better ways to use the available organs.

Superior vena cava syndrome due to thrombotic occlusion in a thrombophilic renal transplant recipient: a case report

The case of a superior vena cava syndrome due to a central venous catheter thrombosis occurring in a second renal transplant patient is described. Imaging revealed thrombosis of the right internal jugular vein with extension along the confluence of the brachiocephalic veins and partial obstruction of the superior vena cava. Anticoagulant therapy with subcutaneous low-molecular-weight heparin was followed by warfarin administration. Despite adequate treatment, the symptomatology worsened because of thrombus organization. A workup revealed a complex prothrombotic underlying condition. Cardiothoracic surgeons were consulted, and an operative reconstruction of the superior vena cava using spiral vein bypass grafting was performed. In this report we describe the clinical presentation, diagnosis, and treatment of this case, with an emphasis on the role of thrombophilia.

Risk Factors That Can Influence Kidney Transplant Outcome

The survival and function of a kidney transplant are influenced by numerous immunological and nonimmunological factors. The aim of this study was to evaluate the role of a number of cadaveric donor parameters on transplanted kidney function, and in particular on the occurrence of delayed graft function (DGF) since DGF is one of the most important factors in long-term organ survival. This study looked at 143 patients who underwent kidney transplant of whom 32 displayed DGF. The creatinine levels in organ recipients, which were evaluated during a follow-up that ranged between 6 months and 4 years, were significantly higher among recipients who developed DGF after transplant (1.8 +/- 0.7 vs 1.4 +/- 0.4; P = .02). The following donor parameters were taken into consideration: history of diabetes and hypertension; creatinine levels; inotropie therapy; problems relating to hemodynamics (hypotension and/or cardiac arrest); and cold ischemia time. We observed that a donor history of hypertension (46.8% DGF vs 23.27% no DGF; P = .01) and high levels of donor creatinine prior to organ removal (1.9 +/- 1.2 mg/dL DGF vs 1.2 +/- 0.9 mg/dL no DGF; P = .007) were significant risk factors for DGF among kidney recipients. No significant differences were found for others factors between recipients with versus without DGF.

Urologic complications in kidney transplantation

Urologic complications in kidney transplantation have an incidence ranging from 3% to 20%, representing an important cause of organ loss. From January 2001 to September 2004, 123 renal transplantations were performed using an immunosuppressive protocol including basiliximab, mycophenolate mofetil, calcineurin inhibitors, and steroids. The surgical technique was vascular anastomoses to external iliac vessels, and ureteral anastomosis according to Lich Gregoire technique using a JJ ureteral stent. We report 5 renal complications (4.2%) and 4 extrarenal complications (3.5%), the majority of which required corrective surgery. The surgical strategy uses the clinical condition of the donor and the recipient; the anatomic anomalies of the graft, and a reduced cold ischemia time. Moreover, a reduction in acute rejection episodes and immediate renal function has been fundamental to reduce urologic complications. In fact, the main cause of urologic complications is ureteral ischemia, linked both to backtable surgery and to rejection episodes. Another important factor in the reduction of early urologic complications has been the routine use of a JJ stent, which allowed us a conservative approach in this setting.

Malignancies After Kidney Transplantation

The most effective treatment of end-stage renal disease is renal transplantation; its superiority to prolong the longevity of patients is well established. Patient and graft survivals have improved with more potent immunosuppression but this advance has been associated with an increased incidence of cancer. The aim of this study was to assess the prevalence of cancer among 265 kidney transplant recipients engrafted between 1968 and October 2004. The overall prevalence of de novo malignancies was 3%. The mean age at diagnosis was 53.3 years (range, 28-63 years) and the duration of the transplant was 11.6 years (range, 0.3-33 years). One patient among 127 (0.8%) who had a history of less than 3 years under immunosuppression, developed a posttransplantation lymphoproliferative disorder (PTLD). Among the 138 patients who had more than 3 years immunosuppression, 7 (5%) developed neoplasms of vulva, colon, native kidneys, prostatic gland, and ovary. One patient was affected by de novo carcinoma in the transplanted kidney. Compared with other published studies, our early cancer prevalence is low, possibly due to a careful history before grafting, good HLA matching, and abstinence from anti-T-cell therapy for treatment of acute rejection episodes. The low level of immunosuppression may account for the low prevalence of neoplasia. The risk of developing a malignancy increases with long-term immunosuppression, comparable with most reports.

Urinary excretion of IgG and alpha(1)-microglobulin predicts clinical course better than extent of proteinuria in membranous nephropathy

In idiopathic membranous nephropathy (MN), the main predictors for progression to chronic renal failure (CRF) are the amount of proteinuria and extent of tubulointerstitial damage. The aim of this study is to evaluate whether urinary excretion of proteins reflecting the alteration of permselectivity in the glomerular capillary wall, such as immunoglobulin G (IgG), and the reabsorption impairment of low-molecular-weight proteins, such as alpha(1)-microglobulin (alpha(1)m), correlates with the extent of tubulointerstitial damage and have a predictive value for functional outcome and response to therapy better than 24-hour proteinuria. In 78 patients with MN, urinary excretion of albumin, transferrin, IgG, and alpha(1)m was measured by immunonephelometry in second-morning urine samples and expressed in milligrams per gram of urinary creatinine (uCr). In 48 patients with characterization of proteinuria and renal biopsy performed at the same time, excretion of IgG (P = 0.0087) and alpha(1)m (P = 0.0024), but not albumin (P = 0.37), transferrin (P = 0.38), or 24-hour proteinuria (P = 0.32), was associated significantly with the extent of tubulointerstitial damage (score, 0 to 1 versus >/=2). Only alpha(1)m excretion was associated significantly with global glomerular sclerosis (P = 0.0032) and arteriolar hyalinosis (P = 0.0004). Moreover, urinary excretion of alpha(1)m was significantly dependent on IgG excretion (r = 0.67; P = 0.0001), but not on albumin (P = 0.66) or 24-hour proteinuria (P = 0.07). Functional outcome could be evaluated in 38 patients with nephrotic syndrome and baseline normal renal function (serum creatinine, 0.99 +/- 0.20 mg/dL; follow-up, 44 +/- 22 months). Remission was 100% versus 20% in patients with IgG excretion less than 110 mg/g uCr versus 110 mg/g uCr or greater (P = 0.0001) and 77% versus 17% in patients with alpha(1)m excretion less than 33.5 mg/g uCr versus 33.5 mg/g uCr or greater (P = 0.0009), respectively. In patients with IgG and alpha(1)m excretion less than or greater than the cutoff value, progression to CRF was 0% versus 35% (P = 0.0026) and 0% versus 58% (P = 0.0001), respectively. Nineteen patients treated with immunosuppressive therapy were compared with 19 untreated patients. There was no difference in remission or progression between treated and untreated patients when IgG and alpha(1)m excretion were less than the cutoff value. There was a significant difference for progression to CRF between treated and untreated patients when alpha(1)m excretion was greater than the cutoff value (17% versus 100%; P = 0.0076). In conclusion, IgG excretion is associated significantly with the extent of tubulointerstitial damage and alpha(1)m excretion. This observation supports the hypothesis that IgG may be the toxic moiety of proteinuria. Excretion of IgG and alpha(1)m has a significant predictive value for both remission and progression and is useful to identify patients who are at risk for progression and for whom treatment with immunosuppressive therapy is indicated soon after diagnosis.

A modern approach to selectivity of proteinuria and tubulointerstitial damage in nephrotic syndrome

BACKGROUND

The selectivity of proteinuria, introduced in clinical nephrology in 1960 and useful in predicting steroid responsiveness in nephrotic syndrome, found little place in clinical practice in subsequent decades, since its assessment did not appear to help predict histologic diagnosis or determine prognosis. The amount of proteinuria and the degree of tubulointerstitial damage appeared to be better predictors of functional outcome. A correlation between them has been found, referred to some toxicity of proteinuria on tubular cells, but so far no single feature or component of proteinuria has been identified as being responsible for this toxicity.

METHODS

We evaluated 89 patients with nephrotic syndrome [9 with minimal change disease (MCD), 29 with primary focal segmental glomerulosclerosis (FSGS), and 51 with idiopathic membranous glomerulonephritis (MGN)] to determine if the selectivity of proteinuria was associated with tubulointerstitial damage. A semiquantitative grading of histologic lesions and qualitative evaluation of the "tubular" component of proteinuria expressed as a pattern of sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and as fractional excretion of the low molecular weight (LMW) protein alpha1-microglobulin (FE alpha1m) were used. A second aim of the study was to assess the predictive value on functional outcome [remission or progression to chronic renal failure (CRF)] and response to therapy of the selectivity of proteinuria, considered alone and in combination with FE alpha1m.

RESULTS

Proteinuria was classified as highly selective [selectivity index (SI) < or = 0.10, N = 15], moderately selective (SI > or = 0.11 < or = 0.20, N = 34), or nonselective (SI > or = 0.21, N = 40). A significant relationship was found between the SI and the histologic degree of tubulointerstitial damage (score 0 to 1 vs. score > or =2, P = 0.000), severity of the tubular component of proteinuria (mixed SDS-PAGE pattern with LMW proteins not lower than 23 kD vs. mixed pattern with LMW proteins up to 20 to 10 kD, P = 0.000), and FE alpha1m (values below vs. above a defined cut-off, P = 0.000). The functional outcome was evaluated in 60 patients with baseline normal renal function (serum creatinine 0.97 +/- 0.19 mg/dL). The patients with high, moderate, or nonselective proteinuria had 100, 50, and 29% of complete or partial remission (P = 0.0001) and 0, 25, and 35% of progression to CRF, respectively (P = 0.050). In 45 patients with moderately selective (N = 28) and nonselective (N = 17) proteinuria, according to some arbitrary cutoffs for FE alpha1m (MGN, < or = vs. > 0. 240% of creatinine clearance; FSGS and MCD, < or = vs. > 0.350%), the remission rate was 62 versus 6% in patients with FE alpha1m below or above the cutoffs (P = 0.0001), and progression to CRF was 7 and 69%, respectively (P = 0.0001). The response to therapy (complete or partial remission at the last observation), evaluated retrospectively in 40 patients, was 100, 67, and 33% in high, moderate, and nonselective proteinuria (P = 0.0002); in 30 patients with moderate and nonselective proteinuria, according to an FE alpha1m value that was < or = or > the cutoffs, the response rate was 75 versus 10% (P = 0.001).

CONCLUSIONS

There is a significant relationship between selectivity of proteinuria and tubulointerstitial damage. Moreover, the selectivity of proteinuria has a predictive value on functional outcome. When proteinuria is highly selective, the tubulointerstitial damage is rather infrequent, and 100% of patients develop clinical remission. When proteinuria is moderately selective or nonselective, increasing numbers of patients develop tubulointerstitial damage; in these patients, the functional outcome and response to therapy is partly dependent on tubulointerstitial involvement, and the best predictor of functional outcome is the combination of SI and FE alpha1m.

Biochemical studies on a novel antioxidant from lemon oil and its biotechnological application in cosmetic dermatology

It is generally accepted that lipid peroxides play an important role in the pathogenesis of free radical-induced cellular injury and that antioxidants such as glutathione, ascorbic acid and alpha-tocopherol are vital in cellular defense against endogenous and exogenous oxidants. The purpose of this study was to investigate the effectiveness of a natural compound, derived from lemon oil extract, in controlling free radical-induced lipid peroxidation and tissue damage in the skin. We provide evidence that a compound isolated from lemon oil, which we have called Lem1, is endowed with a strong antioxidant activity and that it is capable of inhibiting free radical-mediated reactions, evaluated by both in vitro and in vivo biochemical systems. The present study aims to give a preclinical perspective on the biochemical properties of Lem1, a natural compound, as well as to provide a better understanding of the endogenous antioxidant potential of skin and the real validity of a natural antioxidant biotechnology in the antiaging management of the skin.

Formation of propionate after short-term ethanol treatment and its interaction with the carnitine pool in rat

Organic acidurias are genetic disorders of mitochondrial metabolism that lead to the accumulation in tissues and biological fluids of organic acids. It has been demonstrated that interaction of carnitine with the cellular CoA pool, through the production of acyl-carnitines, is potentially critical for maintaining normal cellular metabolism under conditions of impaired acyl-CoA use and that exposure of humans and other mammals to ethanol effects leads to impairment of mitochondrial function. The aim of the present study was to evaluate the role of ethanol on urinary excretion of short-chain organic acids and endogenous carnitines in rats. The data reported show that ethanol significantly increases urinary excretion of propionate, methylmalonate, as well as free acetate, butyrate, pyruvate, lactate, and beta-hydroxybutyrate. Furthermore, the increased formation of propionate and methylmalonate was dependent on the dose of ethanol; did not require the metabolism of ethanol, as was shown in experiments with pyrazole treatment of ethanol rats; and appears to be mediated by beta-adrenergic mechanisms because propranolol almost completely suppresses propionate accumulation. Alcohol administration also increased excretion of specific acyl-carnitines, corresponding to the accumulating acyl groups, whereas excretion of free carnitine was significantly reduced, with respect to control values. The data presented indicate that the short-term ethanol administration is associated with increased excretion of selected organic acids. This study suggests that endogenous carnitine pool might play a role against the deleterious effects of accumulating short-chain organic acids.

An ex vivo biochemical model to study the antioxidant clinical properties of cosmetic products in human antiaging skin care

It is generally accepted that lipid peroxides play an important role in the pathogenesis of free radical-induced cellular injury and that endogenous thiols are vital in cellular defense against oxidative stress. The purpose of this study was to investigate in cultured human skin fibroblasts the effect of oxidative stress on the synthesis of heat shock protein (HSP70) and on the sulfhydryl group content in the absence and presence of alpha-tocopherol as an antioxidant compound. The interesting observation emerging from this study was a marked increase in malonaldehyde and fluorescent peroxide levels associated with a significant thiol depletion and induction of HSP70 stress proteins observed in primary cultures of normal human skin fibroblasts subjected to heat shock or incubated with hydrogen peroxide. These changes were significantly reduced in the presence of alpha-tocopherol. Our findings suggest a correlation between the mechanisms of oxidative stress, antioxidants and HSP70 induction, which can be assessed to evaluate either the perturbation of skin oxidant/antioxidant balance or the protection afforded by antioxidant test compounds.

Effects of L-carnitine on the formation of fatty acid ethyl esters in brain and peripheral organs after short-term ethanol administration in rat

A study was undertaken in rats to evaluate the effects of short-term oral ethanol administration on the levels of fatty acid ethyl esters (FAEE) in brain and peripheral organs in the presence and absence of pretreatment with L-carnitine. Administration of ethanol to rats for seven days resulted in fatty acid ethyl ester formation, particularly in the heart and brain, but also in the kidney and liver. FAEE generation was associated with a significant increase of GSH transferase activity. Treatment with L-carnitine significantly reduced both FAEE and GSH transferase activity, and these effects were associated with a significant decrease in alcohol blood concentrations. The present evidence supports the hypothesis that fatty acid ethyl esters could be mediators involved in the production of alcohol-dependent syndromes. Administration of L-carnitine through an increment in lipid metabolism and turnover, and by the modulation of cellular antioxidant enzymes, greatly reduces these metabolic abnormalities supporting its potential usefulness as a pharmacological tool in alcoholism management.

Increased cerebrospinal fluid and plasma levels of ultraweak chemiluminescence are associated with changes in the thiol pool and lipid-soluble fluorescence in multiple sclerosis: the pathogenic role of oxidative stress

The pathogenesis of multiple sclerosis (MS), the major neurological disease of young adults in the western world, is still poorly understood and no effective therapy to block MS is yet available. It is generally accepted that reactive oxygen species have a major role in the mediation of cell damage and that free sulfhydryl groups are vital in cellular defense against endogenous or exogenous oxidants. Modification of the cellular oxidant/antioxidant balance has been involved in the neuropathogenesis of several diseases, e.g., stroke, Parkinson's disease, Alzheimer's disease and physiological aging. An increasingly important area of antioxidant defense is based on sulfhydryl chemistry, owing to the role of sulfhydryl groups in the function of macromolecular structures such as enzymes and cellular membranes. The chemical composition of human cerebrospinal fluid (CSF) is considered to reflect brain metabolism and in the present study we provided experimental evidence of a decrease in sulfhydryl groups and increased content of products of lipid peroxidation, such as ultraweak chemiluminescence and liposoluble fluorescence, which we found higher in the CSF and plasma of MS patients than in controls, pointing out the role of oxidative stress in the pathogenesis of MS.

Long-term ethanol administration enhances age-dependent modulation of redox state in central and peripheral organs of rat: protection by metadoxine

Evidence is accumulating that intermediates of oxygen reduction may be associated with the development of alcoholic disease. In addition, free radical-induced perturbation of the oxidant/antioxidant balance in cells is widely recognized as the main causative factor of age-related disorders. In the present work, we investigated the effects of 25 months of ethanol consumption on the antioxidant defense system in different organs of rat in comparison with normal aging, in the absence and presence of treatment with metadoxine, an ion pair composed of pirrolidone carboxylate and pyridoxine. We demonstrate that aged rats underwent a significant perturbation of the antioxidant defense system, as indicated by depletion of reduced glutathione (GSH) content, and increases in oxidized GSH and free radical-induced luminescence associated with a decrease of GSH reductase and an increase of GSH transferase activities. These modifications, observed particularly in the liver and brain with respect to other organs, were enhanced by long-term alcohol exposure, and interestingly, significantly reduced after metadoxine supplementation. Our results indicate that increased GSH transferase activity and decreased GSH reductase activity, followed by thiol depletion, are important factors sustaining a pathogenic role for oxidative stress in aging and in all situations where age-correlated changes occur. Administration of metadoxine greatly reduces these metabolic abnormalities. This evidence supports the pharmacological potential of metadoxine in the management of alcoholic disturbances.

Long-term ethanol administration enhances urinary ultraweak luminescence and age-dependent modulation of redox in central and peripheral organs of the rat

Numerous experimental evidence sustains a pathogenic role for oxidative stress in aging. Acute and chronic ethanol metabolism is also known to be associated with oxidative perturbation of cellular oxidant/antioxidant balance. In the present work we investigated the effects of 25 months of ethanol consumption on the antioxidant defense system in different organs of rats, in comparison with normal and aged animals. We show that aged rats underwent a significant perturbation of the antioxidant defense system, as indicated by depletion of reduced glutathione content, increases in oxidized glutathione and free radical-induced urinary luminescence associated with a decrease of glutathione reductase and increase of glutathione transferase activities. These modifications, observed particularly in the liver and brain, were enhanced by long-term alcohol exposure. Our results indicate that increased glutathione transferase activity and decreased glutathione reductase activity, followed by thiol depletion, are important factors sustaining a pathogenic role for oxidative stress in aging and in all situations where age-correlated changes occur. They also reinforce the oxidative potential of toxic compounds, such as ethanol intoxication.

Stress proteins and SH-groups in oxidant-induced cellular injury after chronic ethanol administration in rat

It is generally agreed that lipid peroxides play an important role in the pathogenesis of ethanol-induced cellular injury and that free sulfhydryl groups are vital in cellular defense against endogenous or exogenous oxidants. It has been observed that oxidative stress induces the synthesis of the 70-kDa family of heat-shock proteins (HSPs). Induction of HSPs represents an essential and highly conserved cellular response to a variety of stressful stimuli. In the present study we measured in various brain areas and in liver the intracellular levels of HSP70 proteins, sulfhydryl groups and the antioxidant enzyme status after chronic administration of mild intoxicating doses of ethanol to rats. Expression of HSP70 in response to alcohol administration was particularly high in the hippocampus and striatum. In these brain areas, the increase in HSP70 protein levels occurred in absence of significant changes of antioxidant enzyme activities and was correlated with a marked depletion of intracellular bound thiols and with a decreased susceptibility to lipid peroxidation. Lower levels of HSP70 induction were found in cortex and cerebellum and were associated to decreases in SOD and CAT enzyme activities, with a lower depletion of protein bound thiols and with an increased susceptibility to lipid peroxidation. This study agrees with our previous results performed on acute alcohol intoxication and supports the hypothesis that HSP70 induction protects the different brain areas against oxidative stress.

Characterization of proteinuria in primary glomerulonephritides: urinary polymers of albumin

In 142 patients with primary glomerulonephritis (GN), there were polymers of albumin (PAs) in the urine samples of 87% of 15 minimal-change disease (MCD) patients, 52% of 27 focal segmental glomerulosclerosis (FSGS) patients, 51% of 47 membranous glomerulonephritis (MGN) patients, 55% of 20 membranoproliferative glomerulonephritis (MPGN) patients, and 9% of 33 immunoglobulin A nephropathy (IgAN) patients (P = 0.000). In IgAN, only three patients with nephrotic syndrome were PA positive. The PAs were significantly correlated with nephrotic syndrome (NS) (P = 0.000) and with the degree of proteinuria, ranging from 8% in patients with proteinuria less than 0.5 g/d to 58% in patients with proteinuria > or = 15.0 g/d (P = 0.001), but 40% of the nephrotic syndrome patients were PA-negative despite values of proteinuria comparable to those of PA-positive patients, suggesting that the presence of PAs is not simply related to protein loss, but probably to some other unidentified factor or lesion. For 72 patients (43 with NS) (22 FSGS, 36 MGN, and 14 MPGN patients) with normal renal function at entry (serum creatinine, 1.02 +/- 0.23 mg/dL) and a mean follow-up duration of 52 +/- 27 months, for whom PAs were determined and urinary protein characterized by sodium-dodecyl-sulphate polyacrylamide gel electrophoresis (SDS-PAGE) at the beginning of the follow-up period, the functional outcome was correlated with the patterns of proteinuria. Chronic renal failure (CRF) developed in 24% of all 72 patients, in 36% of the PA-positive patients, in 9% of the PA-negative patients (P = 0.007), in 44% of the SDS-PAGE 10-kd mixed glomerulotubular pattern patients, and in 17% of the SDS-PAGE 23-kd mixed-pattern patients (P = 0.001). The association of PAs with the 10-kd pattern enhanced the predictive value for CRF outcome: CRF developed in 62% of the PA-positive patients with the 10-kd pattern compared with 11% of the PA-negative patients with the 23-kd pattern (P = 0.0001). CRF developed in 32% of 43 patients with the nephrotic syndrome, in 48% of the PA-positive patients, and in 11% of the PA-negative patients (P = 0.037); in 50% of the 10-kd patients and in 24% of the 23-kd patients (P = 0.007); and in 70% of the PA-positive patients with the 10-kd pattern and 14% of the PA-negative patients with the 23-kd pattern (P = 0.001). In a retrospective study of 21 treated patients (11 FSGS, nine MGN, and one MPGN patient), a response to therapy with complete or partial remission was observed in 57% of all 21 patients; in 58% of patients with the nephrotic syndrome; in 88% of the PA-negative patients versus 38% of the PA-positive patients (P = 0.027); in 90% of the 23-kd patients versus 27% of the 10-kd patients (P = 0.004); and in 100% of the PA-negative patients with the 23-kd pattern versus 12% of the PA-positive patients with the 10-kd pattern (P = 0.001). In conclusion, urinary PAs are associated with GN characterized by lesions mainly localized in the glomerular capillary wall, with the presence of the nephrotic syndrome, and with the degree of proteinuria. In patients with FSGS, MGN, MPGN, and normal renal function at entry, the presence of polymers has a predictive value for CRF outcome; this value is enhanced by the contemporaneous presence of an SDS-PAGE proteinuric pattern with low molecular weight proteins up to 10-kd, which is known to be associated with diffuse tubulointerstitial lesions. Therefore, the best predictive value for either CRF outcome or for response to therapy was provided by a combination between a marker associated with the degree of proteinuria and the types of GN characterized by lesions mainly localized in the glomerular capillary wall and a marker associated with tubulointerstitial damage (SDS-PAGE mixed glomerulotubular pattern with low molecular weight proteins between 20 and 10 kd).

Characterization of proteinuria in primary glomerulonephritides. SDS-PAGE patterns: clinical significance and prognostic value of low molecular weight ("tubular") proteins

In 145 patients with focal segmental glomerulosclerosis (43), membranous glomerulonephritis (72), and membranoproliferative glomerulonephritis (30), 71% with normal renal function (NRF) and 63% with nephrotic syndrome (NS), the proteinuria was evaluated by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) and classified into four main patterns: physiological (termed 70 kd), pure glomerular (150 kd), mixed with low molecular weight (LMW) proteins as low as 23 kd (23 kd), and mixed with very LMW proteins (20 to 10 kd; termed 10 kd). The relative frequencies were 70 kd, 0.7%; 150 kd, 1.4%; 23 kd, 61%; and 10 kd, 37%. Therefore, only the two patterns characterized by LMW ("tubular") proteins were compared to determine whether they have different clinical and prognostic significance. The serum creatinine (sCr) values (P < 0.0001), the degrees of proteinuria (P = 0.007), and the tubulointerstitial damage (P = 0.015) were significantly different in the two subgroups of patients with 23-kd and 10-kd LMW proteinuria; the difference for tubulointerstitial damage was at the limit of statistical significance after Bonferroni correction. In 82 patients with NRF at entry (sCr, 1.00 +/- 0.22 mg/dL; range, 0.6 to 1.4 mg/dL) and a follow-up of 46 +/- 22 months (range, 12 to 84 months), the predictive value of the 23-kd and 10-kd SDS-PAGE patterns on functional outcome (chronic renal failure [CRF] or clinical remission) was evaluated. A total of 12.5% of 64 patients with mixed 23-kd proteinuria and 50% of 18 patients with mixed 10-kd proteinuria developed CRF. At this time, the difference between the survival curves was highly significant (P = 0.0001), as it also was after correction for NS (P = 0.0002). When the statistical analysis was limited to 69 patients with sCr < or = 1.2 mg/dL, the difference was still highly significant (P = 0.0016), as after correction for NS (P = 0.0064). Clinical remission developed in 30% of 64 patients with 23-kd proteinuria and in 33% of 18 patients with 10-kd proteinuria; this difference was not significant. In a retrospective analysis of 20 patients (13 focal segmental glomerulosclerosis and seven membranous glomerulonephritis; 10 with the 23-kd pattern and 10 with the 10-kd pattern) treated with steroids alone or with steroids and cyclophosphamide, 80% of the patients with the 23-kd pattern and 30% of the patients with the 10-kd pattern were responsive to treatment (P = 0.025). The SDS-PAGE patterns of 54 patients with NRF at entry were again evaluated after 48 +/- 22 months: 11 patients who developed clinical remission had changed from a prevalent (91%) 23-kd pattern to a prevalent physiological (55%) or glomerular (36%) pattern; eight patients who had developed CRF showed an increase from 37% to 100% of the 10-kd pattern. In 35 patients with normal and stable renal function (sCr from 1.08 +/- 0.20 mg/dL to 1.06 +/- 0.19 mg/dL) who had persistent proteinuria (20 patients) or NS (15 patients), the rate of the 10-kd pattern increased from 6% to 46% (72% in persistent NS), suggesting an impairment of tubular protein reabsorptive function even without a concomitant impairment of glomerular filtration rate, a phenomenon that can be hypothetically attributed to tubular toxicity of persistent proteinuria. The characterization of proteinuria by SDS-PAGE in primary progressive glomerulonephritis is a useful clinical tool: it can be used to identify the main pathophysiologic determinants of excretion of LMW proteins and it has a predictive value on CRF outcome in patients with NRF, reducing the unpredictability of clinical evolution. In focal segmental glomerulosclerosis and membranous glomerulonephritis, it seems to be of predictive value on responsiveness to therapy; monitoring the SDS-PAGE patterns over time may give some insights into the relationship between the persistent protein loss and the progression of the disease.

Cysteine-induced enhancement of lipid peroxidation in substantia nigra: comparative effect with exogenous administration of reduced glutathione

It is generally accepted that reactive oxygen species have a major role in the mediation of cell damage and that free sulphydryl (SH) groups are vital in cellular defence against endogenous or exogenous oxidants. Modification of cellular oxidant/antioxidant balance has been involved in the neuropathogenesis of several diseases, e.g., stroke, Parkinson's disease, Alzheimer's disease and physiological ageing. An increasingly important area of antioxidant defence is based on sulphydryl chemistry, owing to the role of SH groups in the function of macromolecular structures such as enzymes and cellular membranes. Thiols, however, may themselves generate deleterious free radicals, and thionyl radicals, which have been demonstrated to originate in biological systems through enzymatic reactions of different peroxidases, by reacting with molecular oxygen or hydrogen peroxide are able to promote reactions of oxidatives stress. In the present study we provide experimental evidence suggesting a selective effect of cysteine in promoting reactions of oxidative stress in the brain areas of substantia nigra and septum, but not in other areas. In contrast, exogenous administration of reduced glutathione led to a significant decrease of lipoperoxidation in the brain areas of cortex and hippocampus, associated to selective changes in the endogenous pool of thiols.

Structural characterization and solution properties of an acidic branched (1-->3)-beta-D-glucan from Aureobasidium pullulans

An acidic exopolysaccharide was isolated from a selected strain of Aureobasidium pullulans. On the basis of spectroscopic and chromatographic techniques, the polymer was identified as a beta-D-glucan containing a main chain of (1-->3)-linked beta-D-glucopy-ranosyl units substituted at the O-6 position by single beta-D-glucopyranosyl side chains. The ratio of units in the main chain to units in the side chain was found to be 1.4:1. The ionic character of this exopolysaccharide is due to the presence of malate residues which are linked to the polymer through ester bonds. The degree of substitution was estimated to be very low (0.05). In aqueous solution no signals are present in the NMR spectra strongly suggesting that the polymer adopts a rigid ordered conformation as further confirmed by rheological data. A solvent-induced conformational transition was observed in DMSO in which NMR spectra with good signal-to-noise ratio were obtained. The solution behaviour of the polymer is similar to that of other branched (1-->3)-beta-D-glucans in spite of both the degree of branching and the substitution with malate groups.

Nuclear DNA strand breaks during ethanol-induced oxidative stress in rat brain

Free radical-mediated oxidative damage has been implicated in the pathophysiological mechanisms of apoptosis. In this study we report that statistically significant strand breaks were induced primarily in the hippocampus and cerebellum during chronic, and not acute, ethanol treatment. Damage to DNA observed in hippocampus and cerebellum was also correlated with significant modification in the activities of mitochondrial respiratory complexes I and IV and with a significant increase in lipid peroxidation products. This finding lends support to the fact that hippocampus and cerebellum are brain areas particularly vulnerable to redox changes induced by alcohol intoxication, suggesting lower threshold levels of ethanol tolerance.

Stress proteins and SH-groups in oxidant-induced cell damage after acute ethanol administration in rat

It is generally accepted that lipid peroxides play an important role in the pathogenesis of ethanol-induced cellular injury and that free sulfhydryl groups are vital in cellular defense against endogenous or exogenous oxidants. It has been observed that oxidative stress induces the synthesis of the 70-kDa family of heat-shock proteins (HSPs). Furthermore, induction of HSPs represents an essential and highly conserved cellular response to a variety of stressful stimuli. In the present study, we measured the intracellular levels of HSP 70 proteins after administration of mild intoxicating and grossly intoxicating doses of ethanol to rats. Our results demonstrate that elevated doses of ethanol induce HSP in various brain areas, namely, cerebellum, hippocampus, and to a lesser extent, striatum or liver. Induction of HSP 70 protein was correlated with a marked depletion of intracellular bound thiols and a decrease in lipid peroxidation measured as MDA formation. These studies support the hypothesis that a redox mechanism may be involved in the heat-shock signal pathway.

Compatibility of reduced glutathione (GSH) with different solutions currently used in anesthesia and reanimation

BACKGROUND

Reduced glutathione (GSH) an antioxidant used for i.v. or i.m. administrations, prepared as powder to be diluted in distilled water just before injection (Tationil 600), could lose its antioxidant properties when added to various infusions currently utilized in anesthesia and reanimation.

AIM OF THE WORK

Evaluate in vitro the compatibility of the compound marketed under the trade nome "Tationil 600" with the intravenous infusions in common use in anesthesia and reanimation.

MATERIALS AND METHODS

10 mg GSH (Tationil 600) were added to 10 ml of different solutions: 0.9% saline (I), 5% glucosate solution (II), Normosol-M and 5% glucose (III), 3.5% Emagel (IV), Propofol 10 mg/ml (V), in order to obtain a final solution containing 1 mg og GSH per ml of solution. The different solutions were incubated and aliquots taken at different times and analyzed.

RESULTS

GSH in its commercial preparation proved to be compatible with all solutions examined with exception of solution III, because of the interference of sodium bisolfite.

CONCLUSIONS

Reduced glutathione (Tationil 600) was compatible with solutions I, II, IV and V, used for i.v. administrations in anesthesia and reanimation, and revealed to maintain its antioxidant properties when studied over a period of 24 hours.

Blood volume modeling and refilling rate estimation in hemodialysis by continuous hemoglobin monitoring

Eleven bicarbonate hemodialyses (HD) of 6 patients under constant ultrafiltration were continuously monitored with an optical Hb-meter, considered to be a marker of blood volume (BV) changes. A theoretical model was fed experimental data for prediction of blood volume and estimation of vascular parameters, and a time course of rate of refilling was extrapolated. The adequacy of the model was very good for the time course of BV prediction (r2 = 0.85-0.95, n = 11) and for plasma protein concentration (r2 = 0.83-0.86, n = 2). Parameters estimated included (mean-DS): filtration coefficient (Cf) = 0.22 (0.16) dl/min*mmHg, transcapillary hydrostatic pressure (DP) = 17.80 (3.44) mmHg and protein concentration of the refilling fluid (Cref) = 0.45 (0.30) g/dl. In conclusion our study has shown that the model chosen fits the observed BV profile well in all cases, thus the Hb data series can be used for BV dynamic modeling and for estimation of vascular parameters.