Animal models in peripheral nerve transection studies: a systematic review on study design and outcomes assessment

Aim: Peripheral nerve injury regeneration studies using animal models are crucial to different pre-clinical therapeutic approaches efficacy evaluation whatever the surgical technique explored. Materials & methods: A 944 articles systematic review on 'peripheral nerve injury in animal models' over the last 9 years was carried out. Results: It was found that 91% used rodents, and only 9% employed large animals. Different nerves are studied, with generated gaps (10,78 mm) and methods applied for regeneration evaluation uniformed. Sciatic nerve was the most used (88%), followed by median and facial nerves (2.6%), significantly different. Conclusion: There has not been a significant scale-up of the in vivo testing to large animal models (anatomically/physiologically closer to humans), allowing an improvement in translational medicine for clinical cases.

Treatment of Equine Tarsus Long Medial Collateral Ligament Desmitis with Allogenic Synovial Membrane Mesenchymal Stem/Stromal Cells Enhanced by Umbilical Cord Mesenchymal Stem/Stromal Cell-Derived Conditioned Medium: Proof of Concept

Horses are high-performance athletes prone to sportive injuries such as tendonitis and desmitis. The formation of fibrous tissue in tendon repair remains a challenge to overcome. This impels regenerative medicine to develop innovative therapies that enhance regeneration, retrieving original tissue properties. Multipotent Mesenchymal Stem/Stromal Cells (MSCs) have been successfully used to develop therapeutic products, as they secrete a variety of bioactive molecules that play a pivotal role in tissue regeneration. These factors are released in culture media for producing a conditioned medium (CM). The aforementioned assumptions led to the formulation of equine synovial membrane MSCs (eSM-MSCs)-the cellular pool that naturally regenerates joint tissue-combined with a medium enriched in immunomodulatory factors (among other bioactive factors) produced by umbilical cord stroma-derived MSCs (eUC-MSCs) that naturally contribute to suppressing the immune rejection in the maternal-fetal barrier. A description of an equine sport horse diagnosed with acute tarsocrural desmitis and treated with this formulation is presented. Ultrasonographic ligament recovery occurred in a reduced time frame, reducing stoppage time and allowing for the horse's return to unrestricted competition after the completion of a physical rehabilitation program. This study focused on the description of the therapeutic formulation and potential in an equine desmitis treatment using the cells themselves and their secretomes.

The Role of Early Rehabilitation and Functional Electrical Stimulation in Rehabilitation for Cats with Partial Traumatic Brachial Plexus Injury: A Pilot Study on Domestic Cats in Portugal

This prospective observational cohort pilot study included 22 cats diagnosed with partial traumatic brachial plexus injury (PTBPI), aiming to explore responses to an early intensive neurorehabilitation protocol in a clinical setting. This protocol included functional electrical stimulation (FES), locomotor treadmill training and kinesiotherapy exercises, starting at the time with highest probability of nerve repair. The synergetic benefits of this multimodal approach were based on the potential structural and protective role of proteins and the release of neurotrophic factors. Furthermore, FES was parametrized according to the presence or absence of deep pain. Following treatment, 72.6% of the cats achieved ambulation: 9 cats within 15 days, 2 cats within 30 days and 5 cats within 60 days. During the four-year follow-up, there was evidence of improvement in both muscle mass and muscle weakness, in addition to the disappearance of neuropathic pain. Notably, after the 60 days of neurorehabilitation, 3 cats showed improved ambulation after arthrodesis of the carpus. Thus, early rehabilitation, with FES applied in the first weeks after injury and accurate parametrization according to the presence or absence of deep pain, may help in functional recovery and ambulation, reducing the probability of amputation.

Importance of occupational support for NHS patients with mental illness

BACKGROUND

Unemployment is a structural inequality which raises the risk of premature deaths among people with mental illness.

AIMS

This study examined whether UK National Health Service (NHS) patients with mental illness get support to find or keep a job because reducing unemployment rates can reduce the risk of premature mortality.

METHODS

This study analysed recently released data from 54 NHS trusts which randomly sampled patients for a Care Quality Commission survey. This study assessed 11 001 working-age patients with mental illness, of whom 50% are long-term service users (6+ years).

RESULTS

Perceived access to occupational support was poor with 46% of patients who wanted the support saying that they did not get help finding or returning to work. Perceived occupational support for physical co-morbidities needed improvement because 40% of patients with physical co-morbidities did not receive support for physical health needs. Twenty-five per cent said that medication side effects were not discussed, and 24% lacked medication follow-up although 87% of patients found medication beneficial to their mental health. Occupational support significantly benefited overall patient satisfaction to an equivalent extent as the main treatment (i.e. receiving medication and talking therapies), and it was a more consistent predictor of patient satisfaction than talking therapies.

CONCLUSIONS

Improved access to schemes which reduce unemployment among NHS patients with mental illness is needed (e.g. individual placement and support programmes), although limited availability might be due to funding constraints. As well as addressing unemployment, occupational support should address other risk factors for premature mortality, for example, poverty, stigma, discrimination and social exclusion.

Dysphagia and pulmonary complications in acute cerebrovascular disease: A retrospective observational study

INTRODUCTION

Dysphagia is a common post-stroke complication, which may result in serious pulmonary sequelae. Early detection of dysphagia and aspiration risk can reduce morbidity, mortality and length of hospitalization.

OBJECTIVES

This study aims to identify association between dysphagia and acute cerebrovascular disease, and evaluate the prevalence and impact of pulmonary complications on readmissions and mortality.

MATERIAL AND METHODS

Retrospective observational study based on 250 clinical records of patients with acute cerebrovascular disease: clinical history, neurological examination, imaging and Gugging Swallowing Screen in the first 48h. Patients were followed for 3 months via medical records to estimate 3-month mortality and readmissions.

RESULTS

Out of 250 clinical records analyzed, 102 (40.8%) were evaluated for dysphagia. The prevalence of dysphagia was 32.4%. The risk was higher in older patients (p<0.001), in severe stroke (p<0.001) and in the hemorrhagic subtype (p=0.008). An association was found with dysarthria and aphasia (p=0.003; p=0.017). Respiratory tract infections occurred in 14.4% of all patients (GUSS group 11.8% versus no GUSS group 16.2%), and in 75% of those with severe dysphagia (p<0.001). Mortality at 3 months was 24.2% in dysphagic patients, especially high in the severe dysphagia group (75%, p<0.001).

CONCLUSIONS

The type of cerebrovascular disease, NIHSS and GCS scores, age, dysarthria, and aphasia were significant associated factors to dysphagia. The prevalence of respiratory tract infections was higher in patients with no GUSS record, and no statistical significance was observed in related readmissions. Mortality at 3 months was superior in the severe dysphagia group.

Ultrasound Landmarks in the Approach to the Common Peroneal Nerve in a Sheep Model-Application in Peripheral Nerve Regeneration

Peripheral nerve injury (PNI) remains a medical challenge with no easy resolution. Over the last few decades, significant advances have been achieved in promoting peripheral nerve regeneration, and new assessment tools have been developed, both functional and imaging, to quantify the proportion and quality of nerve recovery. The exploration of new animal models, larger, more complex, and with more similarities to humans, has made it possible to reduce the gap between the results obtained in classic animal models, such as rodents, and the application of new therapies in humans and animals of clinical interest. Ultrasonography is an imaging technique recurrently used in clinical practice to assess the peripheral nerves, allowing for its anatomical and topographic characterization, aiding in the administration of anesthesia, and in the performance of nerve blocks. The use of this technique in animal models is scarce, but it could be a useful tool in monitoring the progression of nerve regeneration after the induction of controlled experimental lesions. In this work, sheep, a promising animal model in the area of peripheral nerve regeneration, were subjected to an ultrasonographic study of three peripheral nerves of the hind limb, the common peroneal, and tibial and sciatic nerves. The main aim was to establish values of dimensions and ultrasound appearance in healthy nerves and landmarks for their identification, as well as to perform an ultrasound evaluation of the cranial tibial muscle, an effector muscle of the common peroneal nerve, and to establish normal values for its ultrasound appearance and dimensions. The results obtained will allow the use of these data as control values in future work exploring new therapeutic options for nerve regeneration after induction of common peroneal nerve injuries in sheep.

Advancements and Insights in Exosome-Based Therapies for Wound Healing: A Comprehensive Systematic Review (2018-June 2023)

Exosomes have shown promising potential as a therapeutic approach for wound healing. Nevertheless, the translation from experimental studies to commercially available treatments is still lacking. To assess the current state of research in this field, a systematic review was performed involving studies conducted and published over the past five years. A PubMed search was performed for English-language, full-text available papers published from 2018 to June 2023, focusing on exosomes derived from mammalian sources and their application in wound healing, particularly those involving in vivo assays. Out of 531 results, 148 papers were selected for analysis. The findings revealed that exosome-based treatments improve wound healing by increasing angiogenesis, reepithelization, collagen deposition, and decreasing scar formation. Furthermore, there was significant variability in terms of cell sources and types, biomaterials, and administration routes under investigation, indicating the need for further research in this field. Additionally, a comparative examination encompassing diverse cellular origins, types, administration pathways, or biomaterials is imperative. Furthermore, the predominance of rodent-based animal models raises concerns, as there have been limited advancements towards more complex in vivo models and scale-up assays. These constraints underscore the substantial efforts that remain necessary before attaining commercially viable and extensively applicable therapeutic approaches using exosomes.

Intensive neurorehabilitation and allogeneic stem cells transplantation in canine degenerative myelopathy

Introduction

Degenerative myelopathy (DM) is a neurodegenerative spinal cord disease with upper motor neurons, with progressive and chronic clinical signs, similar to amyotrophic lateral sclerosis (ALS). DM has a complex etiology mainly associated with SOD1 gene mutation and its toxic role, with no specific treatment. Daily intensive rehabilitation showed survival time near 8 months but most animals are euthanized 6-12 months after clinical signs onset.

Methods

This prospective controlled blinded cohort clinical study aims to evaluate the neural regeneration response ability of DM dogs subjected to an intensive neurorehabilitation protocol with mesenchymal stem cells (MSCs) transplantation. In total, 13 non-ambulatory (OFS 6 or 8) dogs with homozygous genotype DM/DM and diagnosed by exclusion were included. All were allocated to the intensive neurorehabilitation with MSCs protocol (INSCP) group (n = 8) or to the ambulatory rehabilitation protocol (ARP) group (n = 5), which differ in regard to training intensity, modalities frequency, and MSCs transplantation. The INSCP group was hospitalized for 1 month (T0 to T1), followed by MSCs transplantation (T1) and a second month (T2), whereas the ARP group was under ambulatory treatment for the same 2 months.

Results

Survival mean time of total population was 375 days, with 438 days for the INSCP group and 274 for the ARP group, with a marked difference on the Kaplan-Meier survival analysis. When comparing the literature's results, there was also a clear difference in the one-sample t-test (p = 0.013) with an increase in time of approximately 70%. OFS classifications between groups at each time point were significantly different (p = 0.008) by the one-way ANOVA and the independent sample t-test.

Discussion

This INSCP showed to be safe, feasible, and a possibility for a long progression of DM dogs with quality of life and functional improvement. This study should be continued.

Allogenic Synovia-Derived Mesenchymal Stem Cells for Treatment of Equine Tendinopathies and Desmopathies-Proof of Concept

Tendon and ligament injuries are frequent in sport horses and humans, and such injuries represent a significant therapeutic challenge. Tissue regeneration and function recovery are the paramount goals of tendon and ligament lesion management. Nowadays, several regenerative treatments are being developed, based on the use of stem cell and stem cell-based therapies. In the present study, the preparation of equine synovial membrane mesenchymal stem cells (eSM-MSCs) is described for clinical use, collection, transport, isolation, differentiation, characterization, and application. These cells are fibroblast-like and grow in clusters. They retain osteogenic, chondrogenic, and adipogenic differentiation potential. We present 16 clinical cases of tendonitis and desmitis, treated with allogenic eSM-MSCs and autologous serum, and we also include their evaluation, treatment, and follow-up. The concerns associated with the use of autologous serum as a vehicle are related to a reduced immunogenic response after the administration of this therapeutic combination, as well as the pro-regenerative effects from the growth factors and immunoglobulins that are part of its constitution. Most of the cases (14/16) healed in 30 days and presented good outcomes. Treatment of tendon and ligament lesions with a mixture of eSM-MSCs and autologous serum appears to be a promising clinical option for this category of lesions in equine patients.

Cellulose-Based Scaffolds: A Comparative Study for Potential Application in Articular Cartilage

Osteoarthritis is a highly prevalent disease worldwide that leads to cartilage loss. Tissue engineering, involving scaffolds, cells, and stimuli, has shown to be a promising strategy for its repair. Thus, this study aims to manufacture and characterise different scaffolds with poly(ε-caprolactone) (PCL) with commercial cellulose (microcrystalline (McC) and methyl cellulose (MC) or cellulose from agro-industrial residues (corncob (CcC)) and at different percentages, 1%, 2%, and 3%. PCL scaffolds were used as a control. Morphologically, the produced scaffolds presented porosities within the desired for cell incorporation (57% to 65%). When submitted to mechanical tests, the incorporation of cellulose affects the compression resistance of the majority of scaffolds. Regarding tensile strength, McC2% showed the highest values. It was proven that all manufactured scaffolds suffered degradation after 7 days of testing because of enzymatic reactions. This degradation may be due to the dissolution of PCL in the organic solvent. Biological tests revealed that PCL, CcC1%, and McC3% are the best materials to combine with human dental pulp stem/stromal cells. Overall, results suggest that cellulose incorporation in PCL scaffolds promotes cellular adhesion/proliferation. Methyl cellulose scaffolds demonstrated some advantageous compressive properties (closer to native cartilaginous tissue) to proceed to further studies for application in cartilage repair.

Assessment of 3D-Printed Polycaprolactone, Hydroxyapatite Nanoparticles and Diacrylate Poly(ethylene glycol) Scaffolds for Bone Regeneration

Notwithstanding the advances achieved in the last decades in the field of synthetic bone substitutes, the development of biodegradable 3D-printed scaffolds with ideal mechanical and biological properties remains an unattained challenge. In the present work, a new approach to produce synthetic bone grafts that mimic complex bone structure is explored. For the first time, three scaffolds of various composition, namely polycaprolactone (PCL), PCL/hydroxyapatite nanoparticles (HANp) and PCL/HANp/diacrylate poly(ethylene glycol) (PEGDA), were manufactured by extrusion. Following the production and characterisation of the scaffolds, an in vitro evaluation was carried out using human dental pulp stem/stromal cells (hDPSCs). Through the findings, it was possible to conclude that, in all groups, the scaffolds were successfully produced presenting networks of interconnected channels, adequate porosity for migration and proliferation of osteoblasts (approximately 50%). Furthermore, according to the in vitro analysis, all groups were considered non-cytotoxic in contact with the cells. Nevertheless, the group with PEGDA revealed hydrophilic properties (15.15° ± 4.06) and adequate mechanical performance (10.41 MPa ± 0.934) and demonstrated significantly higher cell viability than the other groups analysed. The scaffolds with PEGDA suggested an increase in cell adhesion and proliferation, thus are more appropriate for bone regeneration. To conclude, findings in this study demonstrated that PCL, HANp and PEGDA scaffolds may have promising effects on bone regeneration and might open new insights for 3D tissue substitutes.

Effects of Olfactory Mucosa Stem/Stromal Cell and Olfactory Ensheating Cells Secretome on Peripheral Nerve Regeneration

Cell secretome has been explored as a cell-free technique with high scientific and medical interest for Regenerative Medicine. In this work, the secretome produced and collected from Olfactory Mucosa Mesenchymal Stem Cells and Olfactory Ensheating Cells was analyzed and therapeutically applied to promote peripheral nerve regeneration. The analysis of the conditioned medium revealed the production and secretion of several factors with immunomodulatory functions, capable of intervening beneficially in the phases of nerve regeneration. Subsequently, the conditioned medium was applied to sciatic nerves of rats after neurotmesis, using Reaxon^® as tube-guides. Over 20 weeks, the animals were subjected to periodic functional assessments, and after this period, the sciatic nerves and cranial tibial muscles were evaluated stereologically and histomorphometrically, respectively. The results obtained allowed to confirm the beneficial effects resulting from the application of this therapeutic combination. The administration of conditioned medium from Olfactory Mucosal Mesenchymal Stem Cells led to the best results in motor performance, sensory recovery, and gait patterns. Stereological and histomorphometric evaluation also revealed the ability of this therapeutic combination to promote nervous and muscular histologic reorganization during the regenerative process. The therapeutic combination discussed in this work shows promising results and should be further explored to clarify irregularities found in the outcomes and to allow establishing the use of cell secretome as a new therapeutic field applied in the treatment of peripheral nerves after injury.

Mesenchymal Stem/Stromal Cells and Their Paracrine Activity-Immunomodulation Mechanisms and How to Influence the Therapeutic Potential

With high clinical interest to be applied in regenerative medicine, Mesenchymal Stem/Stromal Cells have been widely studied due to their multipotency, wide distribution, and relative ease of isolation and expansion in vitro. Their remarkable biological characteristics and high immunomodulatory influence have opened doors to the application of MSCs in many clinical settings. The therapeutic influence of these cells and the interaction with the immune system seems to occur both directly and through a paracrine route, with the production and secretion of soluble factors and extracellular vesicles. The complex mechanisms through which this influence takes place is not fully understood, but several functional manipulation techniques, such as cell engineering, priming, and preconditioning, have been developed. In this review, the knowledge about the immunoregulatory and immunomodulatory capacity of MSCs and their secretion products is revisited, with a special focus on the phenomena of migration and homing, direct cell action and paracrine activity. The techniques for homing improvement, cell modulation and conditioning prior to the application of paracrine factors were also explored. Finally, multiple assays where different approaches were applied with varying success were used as examples to justify their exploration.

Peripheral Nerve Injury Treatments and Advances: One Health Perspective

Peripheral nerve injuries (PNI) can have several etiologies, such as trauma and iatrogenic interventions, that can lead to the loss of structure and/or function impairment. These changes can cause partial or complete loss of motor and sensory functions, physical disability, and neuropathic pain, which in turn can affect the quality of life. This review aims to revisit the concepts associated with the PNI and the anatomy of the peripheral nerve is detailed to explain the different types of injury. Then, some of the available therapeutic strategies are explained, including surgical methods, pharmacological therapies, and the use of cell-based therapies alone or in combination with biomaterials in the form of tube guides. Nevertheless, even with the various available treatments, it is difficult to achieve a perfect outcome with complete functional recovery. This review aims to enhance the importance of new therapies, especially in severe lesions, to overcome limitations and achieve better outcomes. The urge for new approaches and the understanding of the different methods to evaluate nerve regeneration is fundamental from a One Health perspective. In vitro models followed by in vivo models are very important to be able to translate the achievements to human medicine.

Bio-packaging based on cellulose acetate from banana pseudostem and containing Butia catarinensis extracts

Banana (Musa acuminata) pseudostem cellulose was extracted and acetylated (CA) to prepare membranes with potential use as bio-packages. The CA membrane was embedded by Butia seed (CA-BS) or Butia pulp (CA-BP) extracts obtained from Butia catarinenses (Butia). The produced CA, CA-BS, and CA-BP membranes were evaluated for their physical-chemical, mechanical, thermal, and antibacterial properties. The process for obtaining the cellulose yielded a material with about 92.17% cellulose (DS = 2.85). The purity, cellulose degree acetylation, and the incorporation of Butia extracts into the membranes were confirmed by FTIR. The CA-BS and CA-BP membranes showed a smaller contact angle and higher swelling ratio than the CA membrane. Furthermore, Butia seed or pulp extracts reduced the elastic modulus and deformation at break compared to the CA membrane. The DSC analysis suggested the compatibility between sections and the CA matrix, whereas the TGA analysis confirmed the thermal stability of the membranes. Moreover, less than 1% of the Butia seed and pulp extracts were put into a food simulant media from the membrane. Finally, the CA-BS and CA-BP membranes could inhibit the growth of Staphylococcus aureus and Escherichia coli on their surface, confirming the potential use of these membranes as bio-packaging for food preservation.

The left ventricular remodeling assessment by cardiac magnetic resonance in chronic aortic regurgitation; implications for outcome

Background

Chronic aortic regurgitation (AR) causes left ventricular (LV) volume overload resulting in progressive LV remodeling, which negatively affect clinical outcome. Clinical Guidelines recommend assessment of LV remodeling by echocardiography, but little is known about comparative remodeling quantification by cardiac magnetic resonance (CMR) and association with outcomes.

Purpose

To assess LV remodeling in AR by CMR, compared with echocardiographic measures and determine its impact on clinical outcome.

Methods

Patients with native, ≥moderate, chronic AR by echocardiography who underwent CMR exam within 90 days of diagnosis from January 2012 to February 2020 were enrolled. The endpoint was a composite of death, heart failure hospitalization, and heart failure symptom exacerbation during follow-up.

Results

The 178 patients included had median age (IQR) of 58 years (44–69), and most (88%, n=158) presented with no or minimal symptoms (NYHA class I/II). At diagnosis symptomatic vs. no/minimal symptoms patients presented with much more advanced LV remodeling by CMR (EDVI 133 [83–151] vs. 96 [80–123] p=0.024, ESVI 66 [46–85] vs. 42 [30–58], P=0.001) while echocardiography showed limited differences (EDVI 76 [57–93] vs. 65 [54–87] p=0.507, ESVI 38 [30–58] vs. 27 [20–42], p=0.072). During follow-up (3.3 years [1.6–5.8]), aortic valve replacement (AVR) was performed in 49 patients. In patients with no/minimal symptoms, the composite endpoint occurred in 54 (34%) patients including eight deaths and 30 heart failure hospitalizations. Patients with LV end-systolic volume index (LVESVi) &gt;45 ml/m2 by CMR had higher likelihood for composite endpoint (Panel A) confirmed in multivariate models, adjusting for age, sex, AVR (time-dependent), EuroSCORE2, and LV End-systolic-dimension-index (LVESDi) &gt;25 mm/2, with adjusted hazard ratio 1.84 [1.02–3.33], p&lt;0.044 (Panel B). LVESVi by CMR was at least as powerful in determining clinical outcomes as guideline-recommended Doppler-Echocardiographic variables.

Conclusion

Assessment of LV remodeling by CMR in patients with clinically significant AR is feasible in routine clinical practice, detects with high sensitivity LV remodeling associated with development of HF symptoms and is independently predictive of clinical outcome. Hence, CMR provides a powerful tool for evaluation and risk stratification of patients with AR.

Funding Acknowledgement

Type of funding sources: None. Panel APanel B

Small Ruminants and Its Use in Regenerative Medicine: Recent Works and Future Perspectives

Simple Summary

Small ruminants such as sheep and goats have been increasingly used as animal models due to their dimensions, physiology and anatomy identical to those of humans. Their low costs, ease of accommodation, great longevity and easy handling make them advantageous animals to be used in a wide range of research work. Although there is already a lot of scientific literature describing these species, their use still lacks some standardization. The purpose of this review is to summarize the general principles related to the use of small ruminants as animal models for scientific research.

Abstract

Medical and translational scientific research requires the use of animal models as an initial approach to the study of new therapies and treatments, but when the objective is an exploration of translational potentialities, classical models fail to adequately mimic problems in humans. Among the larger animal models that have been explored more intensely in recent decades, small ruminants, namely sheep and goats, have emerged as excellent options. The main advantages associated to the use of these animals in research works are related to their anatomy and dimensions, larger than conventional laboratory animals, but very similar to those of humans in most physiological systems, in addition to their low maintenance and feeding costs, tendency to be docile, long life expectancies and few ethical complications raised in society. The most obvious disadvantages are the significant differences in some systems such as the gastrointestinal, and the reduced amount of data that limits the comparison between works and the validation of the characterization essays. Despite everything, recently these species have been increasingly used as animal models for diseases in different systems, and the results obtained open doors for their more frequent and advantageous use in the future. The purpose of this review is to summarize the general principles related to the use of small ruminants as animal models, with a focus on regenerative medicine, to group the most relevant works and results published recently and to highlight the potentials for the near future in medical research.

Fifty Shades of Darkness: A Socio-Cognitive Information-Processing Framework Applied to Narcissism and Psychopathy

Existing trait-based and cognitive models of psychopathy and narcissism fail to provide a comprehensive framework that explains the continuum between sub-clinical and clinical presentations of those personalities and to predict associated maladaptive behavior in different social and cultural contexts. In this article, a socio-cognitive information-processing framework for narcissism and psychopathy (SCIPNP) is proposed to explain how psychopathic and narcissistic schemata influence the activation of psychological processes that interact with social and cultural contexts to display those personalities at a sub-clinical level. The proposed framework enables us to predict maladaptive behavior and to explain how sub-clinical narcissists and psychopaths develop personality disorders. The SCIPNP emphasizes the role of culture in shaping motives, appraisals, behavior and affect. Recommendations for future research are provided.

Computed tomography derived left ventricular global longitudinal strain associate with clinical outcomes in patients undergoing transcatheter aortic valve replacement

Funding Acknowledgements

Type of funding sources: None.

Background

Computed tomography angiography (CTA) is key imaging modality for procedure planning for transcatheter aortic valve replacement (TAVR). Functional assessment by CTA with LV global longitudinal strain (LVGLS) has recently shown to be feasible. However, there is limited data on its prognostic value in patients with severe aortic stenosis (AS) who treated with TAVR.

Purpose

To evaluate the association of baseline CTA-LVGLS with post-TAVR outcome.

Methods

 Patients who underwent contrast multiphasic gated CTA for TAVR planning were studied. LVGLS was measured using dedicated feature-tracking software (Medis®). Cox regression analysis evaluated the association of baseline LVGLS with a composite outcome of all-cause death and heart failure hospitalization after TAVR.

Results

A total of 431 patients were included (median [IQR] age, 83 [77,87]years; 44% female); the society of Thoracic Surgeons Predicted Risk of Mortality (STS-PROM) score, 3.3 [2.3,5.1]%; CTA-LVGLS, -18.0 [-21.6,-14.2]%; LV ejection fraction was preserved at 60 [55,65]%. After a median follow-up of 19 [13,27] months, 99 composite outcomes occurred after TAVR. On multivariable Cox regression analysis, LVGLS was associated with the risk of composite outcome even after adjustment for baseline characteristics (Figure A). Patients with reduced LVGLS (above the median &gt;-18.0%) had higher risk of the composite outcome than those with preserved GLS (p = 0.003; Figure B).

Conclusion

Baseline CTA-LVGLS was associated with the risk of death or heart failure hospitalization over the clinical and echocardiographic characteristics in severe AS patients undergoing TAVR.

Abstract Figure.

Computed tomography characteristics of patients with functional MR receiving MitraClip

Funding Acknowledgements

Type of funding sources: None.

Background

Percutaneous leaflet repair with the MitraClip device (Abbott Vascular, Menlo Park, CA) is safe and effective in patients with severe functional mitral regurgitation (FMR). Residual or recurrent MR may occur in up to 40% of patients and is associated with persistent symptoms and impaired survival. The anatomical characteristics associated with residual or recurrent MR after MitraClip are not well defined by computed tomography angiography (CTA) in FMR population.

Methods

A retrospective analysis of patients with significant FMR, who underwent retrospective-gated CTA at Minneapolis Heart Institute between July 2015 to January 2020, identified those who underwent percutaneous leaflet repair with MitraClip. Anatomical and functional parameters were assessed by pre-procedure CTA and compared between those with and without residual (≥2) MR.

Results

  A total of 25 patients were included (median[Q1, Q3]; age, 80[75, 85]; 44% men) and classified into ventricular FMR (V-FMR, n = 12) and atrial FMR (A-FMR, n = 13) according to anatomical and functional characteristics by CTA. 50% of V-FMR and 38% of A-FMR had residual/worsening MR. Among V-FMR patients with residual/worsening MR, shorter coaptation length was observed (2.2[2, 2.3] mm vs. 3.5[3, 4], p = 0.006) (Figure). No differences in anatomical or functional characteristics were seen in A-FMR patients.

Conclusion

Longer coaptation length in V-FMR is predictive of successful MitraClip procedure, whereas mitral annulus size and cardiac volumes are not.

&lt;Ventricular FMR&gt; Total (N = 12) No residual/no worsening MR (N = 6) Residual/worsening MR (N = 6) P value Septal-lateral diameter, mm 31.9 (30.5, 37.9) 32.2 (30.1, 39.8) 31.9 (29.5, 35) 0.749 Annulus area, cm&sup2; 11.2 (10.4, 13.6) 11.3 (10.1, 14.6) 11.1 (9.6, 12.6) 0.631 Tenting area, cm&sup2; 1.6 (1.3, 2.1) 1.6 (1.2, 2.2) 1.7 (1.2, 2.3) 0.873 Tenting height, mm 8.5 (6.5, 9.7) 8.5 (6.6, 9.3) 8.3 (6.3, 10.1) 0.749 Coaptation length, mm 2.6 (2.1, 3.5) 3.5 (3.0, 4.0) 2.2 (2.0, 2.3) 0.006 &lt;Atrial FMR&gt; Total (N = 13) No residual/no worsening MR (N = 8) Residual/worsening MR (N = 5) P value Septal-lateral diameter, mm 32.3 (29.5, 39.0) 32.0 (29.2, 39.9) 34.3 (30.8, 39.02) 0.464 Annulus area, cm&sup2; 10.3 (9.2, 14.7) 10.2 (9.0, 14.6) 12.4 (9.4, 14.7) 0.661 Tenting area, cm&sup2; 1.2 (0.8, 1.8) 1.1 (0.7, 2.2) 1.3 (0.7, 1.8) 0.884 Tenting height, mm 5.5 (4.1, 6.9) 6.3 (4.1, 8.7) 4.6 (3.7, 5.8) 0.213 Coaptation length, mm 2.3 (1.5, 2.8) 2.5 (1.4, 3.5) 1.9 (1.5, 2.6) 0.464 Comparison of baseline CT parameters between no residual/ no worsening MR and residual/ worsening MR Abstract Figure.

Frequency and clinical impact of different definitions of moderate aortic stenosis

Background

Current echocardiographic guidelines recommend five parameters to define severity of aortic stenosis (AS): peak velocity (PV), mean gradient (MG), aortic valve area (AVA), index AVA (AVAi), and dimensionless index (DI). However, the clinical utility of these parameters for patients with moderate AS largely remain unknown.

Objective

To investigate the clinical profiles and outcomes of patients with moderate AS according to five different definitions for severity.

Methods

Using standard echocardiographic definitions, we identified patients with moderate AS who were evaluated in our health care system from 2011 to 2012. Patient demographics, morbidities, and adverse events were reviewed, including death, heart failure (HF) admission, and aortic valve replacement (AVR).

Results

We enrolled 1,042 patients (age, 75±12 yrs; 40% women). Very few patients (4%) met all five criteria for moderate AS, while 49% had only one or two criteria met. DI was the most common parameter for defining moderate AS, employed in 93% of patients. Patients with area-based indices (i.e., AVA, AVAi, DI) had lower stroke volume index, lower mean gradients, lower peak velocities, and more morbidities in comparison to those flow-based definitions of severity (i.e., PV, MG). During a median follow-up of 5.7 years, overall survival was poor with all-cause mortality of 62.8%. Notably, there was no difference in the rates of mortality (range, 56.4 to 63.3%) or HF hospitalization (range, 28.9 to 32.2%) for groups defined by the five parameters, though patients with flow-based definitions more likely had AVR in follow-up.

Conclusions

Most patients with moderate AS meet the definition for severity with one or few criteria. Regardless of the method of definition for severity, a high rate of mortality and morbidity can occur in patients with moderate AS. Further study to optimize the clinical outcomes of patients with moderate AS is warranted.

Funding Acknowledgement

Type of funding source: Foundation. Main funding source(s): Minneapolis Heart Institute Foundation

Interoception Enhanced via the Ears?

Abstract. Heartbeat perception tasks are used to measure interoceptive accuracy. This paper explores the effect of reducing external auditory stimuli on heartbeat perception. Three samples (121 participants in total) performed a heartbeat perception task. Samples 1 and 2 wore ear-protectors and sample 3 did not. There were no differences in interoceptive accuracy between samples 1 and 2 but samples 1 and 2 showed significantly higher interoceptive accuracy than sample 3. These results suggest ear-protectors could be used to manipulate heartbeat perception and that the auditory component of heartbeat perception might be given greater consideration.

The Roles of Socioeconomic Status, Occupational Health and Job Rank on the Epidemiology of Different Psychiatric Symptoms in a Sample of UK Workers

There is a considerable gap in epidemiological literature about community mental health showing how psychiatric symptoms are associated with job rank, socioeconomic status, and occupational health. We examine data from 4596 employees collected in the United Kingdom's Psychiatric Morbidity among Adults Living in Private Households Survey. There were 939 workers in managerial jobs, 739 in supervisory jobs and 2918 employees in lower ranking jobs. Of the 4596 workers, 2463 had depressive symptoms and 2133 no depressive symptoms. Job rank, household gross income, social class, personal gross income and socio-economic group were significantly associated with general health, occupational health and depressive and avoidant symptoms. Job rank, occupational and physical health also explained the variance in paranoid and avoidant symptoms among the employees. This study shows that severe psychopathology is related to workers' job rank.

A structural equation model to predict pre-exposure prophylaxis acceptability in men who have sex with men in Leicester, UK

OBJECTIVES

Pre-exposure prophylaxis (PrEP) is an effective HIV prevention tool for high-risk men who have sex with men (MSM). However, acceptability and uptake have been variable. This study explored the factors that predict PrEP acceptability in MSM in Leicester, where HIV prevalence is double the national average.

METHODS

A total of 191 HIV-negative MSM completed a cross-sectional survey. Participants provided demographic information, and completed measures of HIV knowledge, perceived HIV risk, engagement in sexual risk behaviour, acquisition of a sexually transmitted infection (STI) in the last 12 months, frequency of HIV testing and PrEP acceptability.

RESULTS

Kruskal-Wallis tests showed statistically significant effects of sexual orientation, education level and income, respectively, on HIV knowledge. Gay-identified individuals possessed greater HIV knowledge than bisexuals. Respondents with General Certificate of Secondary Education (GCSE)-level education had significantly less HIV knowledge than those educated to postgraduate level. Respondents with income of < £10 000 possessed significantly less HIV knowledge than higher income groups. Structural equation modelling showed that the relationship between HIV knowledge and PrEP acceptability was mediated by perceived HIV risk, engagement in sexual risk behaviour, acquisition of an STI in the past 12 months and frequency of HIV testing.

CONCLUSIONS

The results reveal socio-economic inequalities in HIV knowledge and HIV testing, and suggest that MSM who have high levels of HIV knowledge and perceived HIV risk and who regularly test for HIV are most likely to endorse PrEP as personally beneficial. HIV knowledge and accurate risk appraisal should be promoted in MSM. The HIV testing context constitutes an ideal context for promoting PrEP to high-risk MSM.

Polychlorinated biphenyls (PCBs) and p,p'-dichlorodiphenyldichloroethylene (DDE) concentrations in maternal and umbilical cord serum in a human cohort from South Portugal

Organochlorine compounds as polychlorinated biphenyls (PCBs) and pp'-dichlorodiphenyldichloroethylene (pp'DDE) are ubiquitous, resistant to degradation and lipophilic compounds, commonly found in the general population. Prenatal exposure to these compounds has been associated to adverse developmental effects. Levels of PCBs and pp'DDE were investigated in maternal and umbilical cord serum of 68 women/newborns pairs from Algarve, South Portugal. Mean sum PCBs congeners and pp'DDE concentrations were 1.62 ± 0.39 ng mL(-1)and 1.11 ± 0.69 ng mL(-1)-for maternal and 1.45 ± 0.25 ng mL(-1) and 0.85 ± 0.50 ng mL(-1)for cord serum, respectively. Congeners distribution pattern followed the order PCB 153>180>130, both for maternal and cord serum). Significant correlations (p<0.05) were found between maternal and cord serum concentrations. The umbilical cord/maternal serum ratio were 0.90 and 0.76, respectively for ΣPCB and pp'DDE Multivariate analyses relate women in urban centers with higher PCB levels, while higher pp'DDE relates to older primiparous women that live at rural areas. PCBs were also correlated to more portions of fat rich foods, while pp'DDE is associated to higher ingestion of vegetables and fruits. Smoking habits only correlated to maternal PCB. The present work provides, to our knowledge and for the first time, baseline human-biomonitoring data and establishes background ranges of PCB and pp'DDE levels in the maternal and umbilical cord serum in the Algarve region. These compounds exhibited the capacity to pass the placenta barrier and target the fetus. Even in non-industrialized areas, and in non-intensive agriculture areas, like the Southern Portugal, there is a need to take measures to eliminate or minimize the risk of organochlorine exposure during pregnancy.

Modeling fish biological responses to contaminants and natural variability in estuaries

Understanding the factors that influence biological responses to contaminants has long been a major goal in marine environmental research. Seven estuarine sites along the Portuguese coast were sampled over a year, and different biological responses of Pomatoschistus microps and Atherina presbyter were determined: superoxide dismutase, catalase, ethoxyresorufin O-deethylase, glutathione S-transferase, metallothioneins, lipid peroxidation, RNA:DNA ratio and condition factor K. Generalized linear models (GLM) were developed for each biological variable per species in relation to sediment chemical characterization (metals and polycyclic aromatic hydrocarbons concentration) and environmental conditions (month, site, water temperature, salinity, depth and mud percentage in the sediment). GLM varied in explanatory power and in the set of predictor variables included in the models. Environmental factors were frequently selected as predictor variables. Individual metals concentration and sediment quality guidelines (integrating all metals) were the major contaminants explaining biological variability. Accordingly, models for metallothioneins and lipid peroxidation had highest explanatory power. Species-specific responses and dataset size were the basis of observed differences between GLM for the two species.

Thoracic splenosis as a differential diagnosis of juxtapleural nodules

Thoracic splenosis is rare and consists of ectopic implantation of splenic tissue into the chest after concomitant thoracic and abdominal trauma with diaphragm injury. It occurs in about 18% of cases of splenic ruptures. In almost all cases, diagnosis is given incidentally once patients are usually asymptomatic. Thoracic splenosis should be considered as a differential diagnosis in all patients with history of trauma presenting with juxtapleural nodules in chest computed tomography. However, malignant conditions should be ruled out firstly. Biopsy is not essential for the diagnosis once nuclear medicine can confirm splenosis in patients with pertinent history of trauma and suggestive tomographic image. We present a typical case of thoracic splenosis whose diagnosis was made by nuclear medicine and no invasive procedures were required.

Are standard heart rate variability measures associated with the self-perception of stress of firefighters in action?

Stress is a major factor for the degradation of cardiac health in first responder professionals such as firefighters. Monitoring stress during real events might be the key for controlling this problem. In this paper we inspect how standard heart rate variability (HRV) measures are associated with the self-perception of stress of firefighters in action, supported by an advanced technological solution to acquire this data. Results obtained from more than 94 hours of annotated ECG recordings of firefighters in action are promising, showing positive association with various standard HRV measures. Given the richness of the gathered data, we have also measured the association of the HRV measures with the stage of a firefighting event (pre, during, post), obtaining some interesting results that hint that the psychological impact of the post-event may be one of the most concerning situations for a firefighter, motivating further studies on this in the future.

Vital analysis: annotating sensed physiological signals with the stress levels of first responders in action

First responders such as firefighters are exposed to extreme stress and fatigue situations during their work routines. It is thus desirable to monitor their health using wearable sensing but this is a complex and still unsolved research challenge that requires large amounts of properly annotated physiological signals data. In this paper we show that the information gathered by our Vital Analysis Framework can support the annotation of these vital signals with the stress levels perceived by the target user, confirmed by the analysis of more than 4600 hours of data collected from real firefighters in action, including 717 answers to event questionnaires from a total of 454 different events.

Responses of CYP450 dependent system to aliphatic and aromatic hydrocarbons body burden in transplanted mussels from South coast of Portugal

Mussels Mytilus galloprovincialis were cross-transplanted at South Portugal from a reference site (site 1) to a site more contaminated with hydrocarbon compounds (site 2), and vice versa, in an active biomonitoring (ABM) concept, to assess the biotransformation capacity catalyzed by the mixed function oxygenase (MFO) system. Total alkanes (TAlk), the unresolved complex mixture (UCM), and total polycyclic aromatic hydrocarbons (TPAHs) concentration increased respectively 6, 4.4 and 4.2 fold relatively to control, in mussels transplanted from site 1 to 2. In the cross-transplant, a 48, 57 and 62% depuration of TAlk, UCM and TPAHs concentrations occurred by the end of the 3-4th week. Petrogenic and biogenic (marine and terrigenous) sources of AHs, and petrogenic and pyrolitic (biomass and oil/fuel incomplete combustion) sources of PAHs were detected at both sites. CYP450, CYT b (5) and NADPH-RED in mussels transplanted from site 1 to 2 were induced from day 0 to 28, with a total increase of 35, 32 and 35%, respectively, while biochemical equilibrium to lesser environmental contamination occurs in mussels transplanted from site 2 to 1. A significant relationship between CYP450 and NADPH-RED was found with TPAH, with distinctive behavior at the two sites. MFO system components increase with exposure time at one site and decreases in the other, reflecting an adaptation to distinct environmental hydrocarbon loads. The ABM strategy proved to be useful to understand the environment real impact on the biochemical responses in mussels' local populations. In this study, CYP450 and NADPH-RED are a useful biomarker for hydrocarbon exposure.

A multibiomarker approach in the clam Ruditapes decussatus to assess the impact of pollution in the Ria Formosa lagoon, South Coast of Portugal

The Ria Formosa lagoon is an ecosystem whose water quality reflects the anthropogenic influence upon the surrounding areas. In this lagoon, the clam Ruditapes decussatus has a great economical importance and has been widely used as a biomonitor. A multibiomarker approach (δ-aminolevulinic acid dehydratase, metallothionein, lipid peroxidation, acetylcholinesterase, alkali-labile phosphates, DNA damage) was applied to assess the environmental quality of this ecosystem and the accumulation of contaminants and their potential adverse effects on clams. Clams were sampled in different shellfish beds in the period between July 2007 and December 2008 and abiotic parameters (temperature, salinity, pH and dissolved oxygen of seawater and organic matter in the sediment), condition index, metals (Cd, Cu, Zn, Ni, Pb), TBTs and PAHs concentrations were measured in clam tissues. Data was integrated using Principal Component Analyses and biomarker indices: IBR (Integrated Biomarker Response) and HSI (Health Status Index). This multibiomarker approach enabled discrimination of a time and space trend between sites with different degrees of anthropogenic contamination, identifying one of them (site 2) as the most stressful and summer months as the most critical period for clams due to an increase of environmental stress (anthropogenic pressure along with extreme environmental conditions, e.g. temperature, dissolved oxygen, organic matter in the sediments, etc). The selected biomarkers provided an integrated response to assess the environmental quality of the system, proving to be a useful approach when complex mixtures of contaminants occur.

Vital analysis: field validation of a framework for annotating biological signals of first responders in action

First responders are professionals that are exposed to extreme stress and fatigue during extended periods of time. That is why it is necessary to research and develop technological solutions based on wearable sensors that can continuously monitor the health of these professionals in action, namely their stress and fatigue levels. In this paper we present the Vital Analysis smartphone-based framework, integrated into the broader Vital Responder project, that allows the annotation and contextualization of the signals collected during real action. After a contextual study we have implemented and deployed this framework in a firefighter team with 5 elements, from where we have collected over 3300 hours of annotations during 174 days, covering 382 different events. Results are analysed and discussed, validating the framework as a useful and usable tool for annotating biological signals of first responders in action.

Assessment of essential and nonessential metals and different metal exposure biomarkers in the human placenta in a population from the south of Portugal

The general population is exposed to metals as trace amounts of metallic compounds are present in air, water, and food. Information on background exposures and biomarker concentrations of environmental chemicals in the general Portuguese population is limited. Therefore, the purpose of this study was to determine the levels of important nonessential metals with recognized toxicity cadmium (Cd) and lead (Pb) and essential metals copper (Cu), nickel (Ni), chromium (Cr), and zinc (Zn) in placentas of mothers living in south Portugal (Algarve). Due to the difficulty in establishing the effects of chemicals in a complex and variable environment, this study also aimed to examine the response of biomarkers, such as biochemical changes that occurs at subcellular levels in the presence of contaminants. The investigated biomarkers in placentas indicative of metal exposure or damage included the metallothioneins (MT), delta-aminolevulinic acid dehydratase (ALAD) (specific for Pb), and lipid peroxidation (LPO) as an index of oxidative stress damage. Moreover, HJ-BIPLOT was applied in order to identify and categorize mothers vulnerable to environmental contamination in this region. Metal concentrations in the placenta were not excessive but within the range found in most European studies. In general, the biomarkers MT and LPO were positively correlated with metal levels, while with ALAD the opposite occurred, indicating the selected battery of biomarkers were suitable to study the effects of metals on human placenta. Further, the application of multivariate analysis with HJ-BIPLOT showed that most significant factors contributing to maternal and fetal exposures via placenta were dietary and smoking habits.

Short-term variability of multiple biomarker response in fish from estuaries: Influence of environmental dynamics

Short-term variability in biomarker responses and the effects of temperature and salinity variation were explored in three fish species (Dicentrarchus labrax, Solea senegalensis and Pomatoschistus microps) occurring in the Tejo estuary. Short-term variability in biomarkers was observed in all species although no pattern was discerned over time (days to weeks). Antioxidant enzymes activity (superoxide dismutase (SOD) and catalase (CAT)) showed low temporal variability, indicating some constancy or baseline level in antioxidant responses. Only CAT activity in S. senegalensis was correlated with temperature, suggesting that exposure to contaminants triggered antioxidant acclimation. Higher short-term variability was observed in xenobiotic biotransformation enzymes activity (phase I ethoxyresorufin O-deethylase (EROD) and phase II glutathione S-transferase (GST)). Yet a significant correlation between EROD and GST in D. labrax and S. senegalensis suggests a concomitant response to contaminants. Moreover the lack of correlation between xenobiotic biotransformation enzymes and abiotic variables on concordant time scales, suggest a high specificity of these biomarkers to chemical exposure, rather than high variability due to environmental dynamics.

Multi-biomarker responses to estuarine habitat contamination in three fish species: Dicentrarchus labrax, Solea senegalensis and Pomatoschistus microps

Several biomarker responses were determined in three fish species, Dicentrarchus labrax, Solea senegalensis and Pomatoschistus microps, from two estuaries of the Portuguese coast, Ria de Aveiro and Tejo. Both estuaries have significant anthropogenic influences from multiple sources (industrial, agricultural and shipping activities), which was evident from sediment chemical characterization concerning metal (copper, zinc, nickel, lead and chromium) and polycyclic aromatic hydrocarbon (PAH) concentrations. Spatial variability in fish responses was observed across species for most biomarkers of exposure [the activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), ethoxyresorufin O-deethylase (EROD) and glutathione S-transferase (GST), and metallothionein concentrations (MT)] and effect biomarkers [lipid peroxidation (LPO), RNA to DNA ratio (R:D), protein and lipid content]. In general, the interspecific differences in biomarker responses were greater than the spatial differences, due to differences in the behavior and habitat use of the species. Nevertheless, similarities were also observed considering both chemical load and biomarker responses. In highly polluted sites fish showed in general a significant antioxidant enzyme induction, associated with decreased R:D values, while fish from the least impacted site had little enzyme induction and better condition indices (high R:D and low LPO values). EROD activity was also higher for all species in the Tejo than Ria de Aveiro estuary, despite the generally higher total PAH measured in Ria de Aveiro, most likely due to a higher proportion of 4 and 6-ring PAHs, considered more toxic than low molecular weight PAHs, in the Tejo. In conclusion, this multi-biomarker approach considering multiple species provided improved understanding of the diverse responses and effects of exposure to contaminants and the effective risk it poses for different fish species.

Source and impact of lead contamination on δ-aminolevulinic acid dehydratase activity in several marine bivalve species along the Gulf of Cadiz

Coastal areas and estuaries are particularly sensitive to metal contamination from anthropogenic sources and in the last few decades the study of space-time distribution and variation of metals has been extensively researched. The Gulf of Cadiz is no exception, with several rivers draining one of the largest concentrations of sulphide deposits in the world, the Iberian Pyrite Belt (IPB). Of these rivers, the Guadiana, one of the most important in the Iberian Peninsula, together with smaller rivers like the Tinto and Odiel, delivers a very high metal load to the adjacent coastal areas. The purpose of this work was to study the source and impact of lead (Pb) drained from historical or active mining areas in the IPB on the activity of a Pb inhibited enzyme (δ-aminolevulinic acid dehydratase, ALAD) in several bivalve species along the Gulf of Cadiz. Seven marine species (Chamelea gallina, Mactra corallina, Donax trunculus, Cerastoderma edule, Mytilus galloprovincialis, Scrobicularia plana and Crassostrea angulata) were collected at 12 sites from Mazagón, near the mouth of the rivers Tinto and Odiel (Spain), to Cacela Velha (Ria Formosa lagoon system, Portugal). Lead concentrations, ALAD activity and lead isotope ratios ((206)Pb/(204)Pb, (207)Pb/(204)Pb and (208)Pb/(204)Pb) were determined in the whole soft tissues. The highest Pb concentrations were determined in S. plana (3.50±1.09 μg g(-1) Pb d.w.) and D. trunculus (1.95±0.10 μg g(-1) Pb d.w.), while M. galloprovincialis and C. angulata showed the lowest Pb levels (<0.38 μg g(-1) Pb d.w.). In general, ALAD activity is negatively correlated with total Pb concentration. However this relationship is species dependent (e.g. linear for C. gallina ALAD=-0.36[Pb]+0.79; r=0.837; or exponential for M. galloprovincialis ALAD=2.48e(-8.3[Pb]); r=0.911). This indicates that ALAD activity has considerable potential as a biomarker of Pb and moreover, in marine bivalve species with different feeding habits. Lead isotope data showed significant seasonal and spatial changes in bivalve isotopic composition reflecting seasonal and geographic differences in bioaccumulation. Within the study area, Pb can be modelled as a mixing between geogenic Pb and mine-related, discharges of Pb from the IPB. For some sites at the mouth of the Guadiana River, the bivalves show contamination from other anthropogenic sources, such as leaded boat/aviation fuel and/or leaded paint. Finally, the study demonstrates convincingly the need to consider species-specific variation when using bivalve ALAD activity as a biomarker for Pb.

Using biochemical and isotope geochemistry to understand the environmental and public health implications of lead pollution in the lower Guadiana River, Iberia: a freshwater bivalve study

Lead is a natural component of aquatic ecosystems with no known biological role and is highly toxic. Its toxicity stems from its ability to mimic biologically important metals and to produce membrane damage through lipid peroxidation (LPO). Most lead poisoning symptoms are thought to occur by interfering with an essential enzyme, delta-aminolevulinic acid dehydratase (ALAD), the activity of which is markedly inhibited by lead. The purpose of this work was to study the levels and effects of lead pollution (responses of ALAD and oxidative stress biomarker LPO) in the freshwater bivalve Corbicula fluminea along the lower Guadiana River (Portugal and Spain); a major river system impacted by historic mining pollution and more recent anthropogenic inputs. The results show that the enzymatic activity of ALAD is negatively correlated with the total Pb concentration of the whole tissue suggesting that ALAD has considerable potential as a biomarker of lead exposure in C. fluminea. To identify the sources of lead to which bivalves have been exposed, high precision (206)Pb/(204)Pb, (207)Pb/(204)Pb, (208)Pb/(204)/Pb ratios for C. fluminea confirm that historical mining activities in the Iberian Pyrite Belt are the dominant source of lead pollution in the lower Guadiana River. The isotope patterns however exhibit marked seasonal and geographic variation in response to rainfall and river water management. Locally, other anthropogenic sources of lead have been detected in C. fluminea close to population centres, thus adding to its versatility as a freshwater bio-indicator. Overall, the study highlights the value of natural ecosystems as monitors of water quality and their importance for public health assessment and surveillance.

Comparative petroleum hydrocarbons levels and biochemical responses in mussels from hydrothermal vents (Bathymodiolus azoricus) and coastal environments (Mytilus galloprovincialis)

Aliphatic hydrocarbons and PAHs in the whole soft tissues of Bathymodiolus azoricus from three Mid-Atlantic Ridge hydrothermal vents (Menez-Gwen, Lucky Strike and Rainbow), and Mytilus galloprovincialis from three contaminated coastal sites in South Portugal were analysed, and its effects on the digestive gland microsomes mixed-function oxygenase system (MFO) were assessed. Aliphatic hydrocarbons levels were present in the same magnitude in both coastal and hydrothermal environments, while the UCM (unresolved complex mixture) for coastal mussels were higher than in vent mussels. In general, significantly higher PAHs concentrations were found in coastal mussels, compared to B. azoricus where low molecular weight PAHs (2-3 rings) represented the majority of PAHs contrarily to what was observed in M. galloprovincialis. The MFO components were present in both mussel species, and were detected in vent mussels for the first time. However this system seems to have different roles in species from these contrasting environments. In coastal mussels MFO responded to hydrocarbon contamination while response in hydrothermal organisms appeared to be related mainly to endogenous factors.

MAGE-C1/CT-7 expression in plasma cell myeloma: sub-cellular localization impacts on clinical outcome

Plasma cell myelomas (PMs) have a poor prognosis. Cancer-testis (CT) antigens are immunogenic proteins, representing potential targets for tumor vaccination strategies. The expression of the CT antigens GAGE, MAGE-A4, MAGE-C1/CT-7, and NY-ESO-1 was investigated on paraffin-embedded bone marrow biopsies from 219 PM and 8 monoclonal gammopathy of undetermined significance (MGUS) patients. The frequency and prognostic impact of these CT antigens were compared with known morphological prognostic markers (i.e. Mib1 labeling index) and the presence of the translocations t(4;14)(p16.3; q32) and t(11;14)(q13;q32). We show that MAGE-C1/CT-7 is the most prevalent CT antigen, expressed in 57% of PMs in a high percentage of tumor cells. While MAGE-C1/CT-7 was absent in non-malignant plasma cells, plasma cells of patients with MGUS did express MAGE-C1/CT-7, but no other CT antigens. MAGE-C1/CT-7 was more frequently expressed in PMs with an elevated proliferation rate (Mib1 >10%) compared to PMs with a low proliferation rate (Mib1 <or=10%, 71%versus 29%, P < 0.001) and correlated with overall survival, depending on its subcellular distribution. PMs with pure cytoplasmic MAGE-C1/CT-7 expression showed a better prognosis (48 months versus 33 months, P < 0.05) than PMs with combined nuclear-cytoplasmic or nuclear expression only. Thus, expression of MAGE-C1/CT-7 in patients with monoclonal gammopathies represents a predictor of outcome and overt malignant transformation.

Expression and immunogenicity of the cancer-testis antigen CT7 (MAGE-C1) in patients with multiple myeloma

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Introduction: CT7 (MAGE-C1) is an antigen with restricted expression in cancer and testis (CT antigen). It has been demonstrated to be expressed in more than 55% of Multiple Myeloma (MM) bone marrow biopsies (BMB). CT7 immunogenicity was so far unknown. Thus we aimed to analyse the immune response of MM patients towards CT7. Moreover, we evaluated correlations between CT7 expression and prognostic features. Methods: The CT7 gene was cloned from a MM cell line by RT-PCR; the protein has been expressed in E. coli, purified by affinity FPLC and analysed by Mass Spectrometry. MM patients’ sera (1:200 dilution) were analysed towards the CT7 full length protein by Western Blot (WB) and against truncated CT7 by WB and ELISA. BMB were analyzed by immunohistochemistry (IC) for CT7 expression and for proliferation/differentiation markers. Specific chromosomal aberrations were investigated by FISH analysis. Results: Both full-length and truncated proteins have been produced and fully sequenced. Out of 55 patients’ sera 12 typed positive for the full length protein by WB analysis. Ten of sixteen (62.5%) BMB were positive for CT7. So far no correlation with prognostic features was established. Conclusions: For the first time the in vivo immunogenicity of CT7 was demonstrated. Our preliminary data indicate that spontaneous anti-CT7 humoral responses occur in a significant proportion of MM patients. All detectable humoral responses observed to date are in patients with advanced disease. Characterization of antibody-binding sites and specific CD8/CD4 T cell responses in MM patients is on-going. Our data support the broad and strong expression of CT7 in patients with MM. To date CT7 represent the most immunogenic cancer testis antigen in MM.

No significant financial relationships to disclose.