Assessment of sulfonamide contamination in aquatic environments: A first report for Argentina and environmental risk assessment.

The global surge in pharmaceutical consumption, driven by increasing population and the demand for animal proteins, leads to the discharge of diverse pollutants, including antibiotic residues, into water bodies. Sulfonamides, being water-soluble compounds, can readily enter surface run-off, posing potential risks to non-target species despite their low environmental concentrations. Latin America has implemented intensive production systems highly dependent on antimicrobials for productivity and animal health, yet there is a paucity of information regarding their concentration in the region. The objective of this study was to evaluate the presence of sulfonamides in water and sediment samples and assess their potential ecological risks through an environmental risk assessment. The Río de la Plata basin collects the waters of the Paraguay, Paraná, and Uruguay rivers, together with their tributaries and various wetlands, passing through the provinces in Argentina known for their significant animal husbandry production. Two sampling campaigns were carried out for sediment, while only one campaign was conducted for surface waters. The samples were analyzed by high performance liquid chromatography tandem mass-spectrometry (HPLC-MS/MS). None of the examined sulfonamide antibiotics were detected in the sediment samples from both sampling campaigns. In contrast, sulfadiazine (95 %), sulfamethoxazole (91 %), and sulfathiazole (73 %) were detected in the water samples. Sulfadiazine was found in the concentration range of 8 to 128 ng/L, while sulfamethoxazole and sulfathiazole were observed at concentrations ranging from 3.0 to 32.5 ng/L and 2.9 to 8.1 ng/L, respectively. Based on the environmental risk assessment conducted using the sulfonamide concentrations, most samples indicated a medium risk for aquatic biota, with only one sample surpassing the high-risk threshold. This study represents the first report presenting data on the presence of sulfonamide antibiotics in the aquatic environment of Argentina.

Long-term outcome of peripheral T-cell lymphomas: Ten-year follow-up of the International Prospective T-cell Project.

Peripheral T-cell lymphomas (PTCLs) are a heterogeneous group of haematological cancers with generally poor clinical outcomes. However, a subset of patients experience durable disease control, and little is known regarding long-term outcomes. The International T-cell Lymphoma Project (ITCLP) is the largest prospectively collected cohort of patients with PTCLs, providing insight into clinical outcomes at academic medical centres globally. We performed a long-term outcome analysis on patients from the ITCLP with available 10-year follow-up data (n = 735). The overall response rate to first-line therapy was 68%, while 5- and 10-year overall survival estimates were 49% and 40% respectively. Most deaths occurred prior to 5 years, and for patients alive at 5 years, the chance of surviving to 10 years was 84%. However, lymphoma remained the leading cause of death in the 5- to 10-year period (67%). Low-risk International Prognostic Index and Prognostic Index for T-cell lymphoma scores both identified patients with improved survival, while in multivariate analysis, age >60 years and Eastern Cooperative Oncology Group performance status 2-4 were associated with inferior outcomes. The favourable survival seen in patients achieving durable initial disease control emphasizes the unmet need for optimal front-line therapeutic approaches in PTCLs.

Root phosphoenolpyruvate carboxylase activity is essential for Sorghum bicolor tolerance to ammonium nutrition.

Phosphoenolpyruvate carboxylase (PEPC; EC 4.1.1.31) is an enzyme family with pivotal roles in plant carbon and nitrogen metabolism. A main role for non-photosynthetic PEPC is as anaplerotic enzyme to load tricarboxylic acid (TCA) cycle with carbon skeletons that compensate the intermediates diverted for biomolecule synthesis such as amino acids. When plants are grown under ammonium (NH4+) nutrition, the excessive uptake of NH4+ often provokes a stress situation. When plants face NH4+ stress, N assimilation is greatly induced and thus, requires the supply of carbon skeletons coming from TCA cycle. In this work, we addressed the importance of root PEPC and TCA cycle for sorghum (Sorghum bicolor L. Moench), a C4 cereal crop, grown under ammonium nutrition. To do so, we used RNAi sorghum lines that display a decrease expression of SbPPC3 (Ppc3 lines), the main root PEPC isoform, and reduced root PEPC activity. SbPPC3 silencing provoked ammonium hypersensitivity, meaning lower biomass accumulation in Ppc3 respect to WT plants when growing under ammonium nutrition. The silenced plants presented a deregulation of primary metabolism as highlighted by the accumulation of NH4+ in the root and the alteration of normal TCA functioning, which was evidenced by the accumulation of organic acids in the root under ammonium nutrition. Altogether, our work evidences the importance of non-photosynthetic PEPC, and root TCA cycle, in sorghum to deal with high external NH4+ availability.

The role of component separation in the treatment of severe diastasis recti abdominis: a new indication for a known technique.

OBJECTIVE: Diastasis of the rectus abdominis muscle (DRAM) is a widening of linea alba, it also could be accompanied by abdominal bulging. DRAM is often a cause of quality-of-life impairment, especially when it is of large dimensions. Repair with direct rectus plication is the most common treatment for Diastasis Recti Abdominis (DRA), but it can result in high recurrence rates. The authors aimed to show their results in applying the component separation technique in wide DRA cases. PATIENTS AND METHODS: From January 2015 to July 2018, 43 patients with DRA ≥ 10 cm at 3 cm over the umbilicus have been treated with component separation technique associated to panniculectomy. A biologic mesh was positioned onlay in cases of weakness along the semilunaris lines. RESULTS: DRA repair was achieved in all cases. All patients completed the 1-year follow-up and no recurrence nor major complication were registered. Minor complications were observed in 12 (27.9%) cases. CONCLUSIONS: This is the first study describing the component separation technique use in cases of DRA without hernia, associated to abdominoplasty surgery. Preliminary results were encouraging, but larger series are required.

First evidence of environmental bioaccumulation of pharmaceuticals on adult native anurans (Rhinella arenarum) from Argentina.

The presence of pharmaceutically active compounds (PhACs) in surface water is well known, whereas their natural occurrence in biota is much less explored. The aim of this work was to evaluate the bioaccumulation of PhACs in adult toads of the neotropical species Rhinella arenarum. Three sites were selected in Buenos Aires (Argentina): a reference site (Site 1), a site with direct discharge from a secondary wastewater treatment plant (WWTP) (Site 2) and a site 300 m downstream of the WWTP discharge (Site 3). Surface water samples, as well as muscle, liver and fat bodies of toads were collected, extracted and analyzed by LC-MS/MS. Highly significant differences in total PhACs concentration in surface water (p < 0.005) were detected between Site 2 and the other sites. These concentrations ranged from 0.37 to 52.46 ng/L at Site 1, 0.71-6950.37 ng/L at Site 2, and 0.12-75.45 ng/L at Site 3. In general, bioaccumulation of PhACs in toad tissues was similar between sites and tissues of each site. The highest concentrations were detected in the muscle of toads from Site 3 (1.06-87.24 ng/g dw), followed by liver (1.77-38.10 ng/g dw) and fat bodies (0.68-20.59 ng/g dw) from Site 1. Ibuprofen (6950 ng/L), acetaminophen (3277 ng/L) and valsartan (2504 ng/L) were the compounds with the highest concentrations in surface water from Site 2, whereas acetaminophen (87.2 ng/g dw, muscle from Site 3), desloratadine (38.1 ng/g dw, liver from Site 1), and phenazone (25.9 ng/g dw, liver from Site 1) were the ones that showed the highest concentrations in biota. This is the first time a field study has examined the environmental bioaccumulation of PhACs in anurans, demonstrating their potential for monitoring the status of natural ecosystems.

The Combined Use of Curcumin and Platelet-Rich Plasma Enhances Axonal Regeneration in Acute Nerve Injuries: An Experimental Study in a Rat Model.

Introduction The aim of this study was to determine if the combined use of curcumin and platelet-rich plasma (PRP) improves the axonal regeneration process in acutely repaired nerve injuries. Materials and Methods The right sciatic nerves of 32 Holtzman albino rats were transected and immediately repaired. Four treatments were randomly allocated: (1) nerve repair only; (2) nerve repair + local PRP; (3) nerve repair + intraperitoneal curcumin; and (4) nerve repair + local PRP + intraperitoneal curcumin. Clinical (estimation of sciatic functional index) and electrophysiological outcomes were assessed 4 and 12 weeks after surgery, and histologic evaluations performed 12 weeks after surgery. Results Group IV (PRP + curcumin) resulted in significantly better outcomes across all the evaluation parameters, compared with the other three groups ( p < 0.05). Additionally, when used as single adjuvants, both the curcumin (group III) and PRP (group II) groups showed significant improvement over the control group ( p < 0.05). No significant differences were found between PRP and curcumin when used as sole adjuvants. Conclusion The combined administration of curcumin + PRP as adjuvants to nerve repair could enhance axonal regeneration in terms of clinical, electrophysiological, and histological parameters in a rat model of acute sciatic nerve injury.

Decellularized allografts as an alternative for reconstruction of large inferior alveolar nerve defects: a systematic review.

BACKGROUND: Inferior alveolar nerve (IAN) injuries are a clinical problem with devastating consequences, causing temporary or permanent paresthesia, significantly affecting the patient's quality of life. Despite morbidity, side effects and controversy regarding its results, autologous nerve grafting is still the main treatment for these type of lesions. However, due to advances in knowledge about nerve damage and with the aim of preventing the described problems of autografts, new treatment alternatives based on decellularized allografts have emerged. The aim of this systematic review was to evaluate the reported efficacy of decellularized allografts for the treatment of IAN damage. MATERIAL AND METHODS: We performed a systematic search in Pubmed, Scopus and Web of Science databases following the PRISMA guidelines. Cohort studies, randomized or non-randomized clinical studies, prospective or retrospective studies, without age limits and language restriction that included human subjects who received decellularized allograft as treatment for IAN damage were included. RESULTS: Six articles met the inclusion criteria and were included for data analysis. In all 6 articles, resolution of IAN damage was observed in more than 85% of patients after a 12-month follow-up period, and in 2 of them, complete resolution was observed in 100% of their patients at longer follow-ups. CONCLUSIONS: Decellularized allograft appears to be a promising alternative to resolve IAN lesions, without requiring a nerve autograft procedure. However, more randomized clinical trials are needed to validate adequate treatment modalities with decellularized allografts.

Apremilast as a target therapy for nail psoriasis: a real-life observational study proving its efficacy in restoring the nail unit.

PURPOSE: Psoriasis, Psoriatic Arthritis and Nail psoriasis are chronic diseases that share a common underlying etiology of immunity dysregulation, enhanced activation of inflammatory pathways and remitting-relapsing course. Although nails represent a small percentage of the body surface involvement of this site can lead to impaired quality of life, severe discomfort and even result in permanent disability. Current therapeutic options for nail psoriasis include a variety of topical and systemic treatments although they are often reported as unsatisfactory from patients either due to their poor effectiveness or disturbing side effects. Recently small molecule drugs such as the PDE4 inhibitors were introduced in clinical practice and specifically apremilast has shown to be an effective new treatment option for psoriasis and psoriatic arthritis. Considering either the specific mechanism of action of apremilast, we performed a real-life observational study of 24 weeks assessing apremilast role in nail psoriasis. MATHERIALS AND METHODS: Patients received apremilast 30mg bid, orally. Safety and efficacy were assessed at weeks 0, 4, 8, 12 and 24 using Dermatologic Life Quality Index (DLQI) and Nail Area Psoriasis Severity Index (NAPSI). At T0 we took a nail sample to investigate the presence of onychomycosis. Culture tests were performed in all the patients to search for fungi. RESULTS: We recruited a total of 15 patients with nail psoriasis. The analysis of variance (one-way ANOVA) showed the following results: DLQI (F.15.7; p-value < .00001) and NAPSI (F.9.4; p-value < .00001). Three patients (20%) presented also onychomycoses at the beginning of the treatment. CONCLUSIONS: Apremilast showed fast and sustained improvement of nail psoriasis over time and a complete resolution of life quality impairment due to the disease.

Immunomodulatory agents as potential therapeutic or preventive strategies for COVID-19.

Currently, the COVID-19 pandemic, caused by the novel SARS-CoV-2 coronavirus, represents the greatest global health threat. Most people infected by the virus present mild to moderate respiratory symptoms and recover with supportive treatments. However, certain susceptible hosts develop an acute respiratory distress syndrome (ARDS), associated with an inflammatory "cytokine storm", leading to lung damage. Despite the current availability of different COVID-19 vaccines, the new emerging SARS-CoV-2 genetic variants represent a major concern worldwide, due to their increased transmissibility and rapid spread. Indeed, it seems that some mutations or combinations of mutations might confer selective advantages to the virus, such as the ability to evade the host immune responses elicited by COVID-19 vaccines. Several therapeutic approaches have been investigated but, to date, a unique and fully effective therapeutic protocol has not yet been achieved. In addition, steroid-based therapies, aimed to reduce inflammation in patients with severe COVID-19 disease, may increase the risk of opportunistic infections, increasing the hospitalization time and mortality rate of these patients. Hence, there is an unmet need to develop more effective therapeutic options. Here, we discuss the potential use of natural immunomodulators such as Thymosin α1 (Tα1), all-trans retinoic acid (ATRA), and lactoferrin (LF), as adjunctive or preventive treatment of severe COVID-19 disease. These agents are considered to be multifunctional molecules because of their ability to enhance antiviral host immunity and restore the immune balance, depending on the host immune status. Furthermore, they are able to exert a broad-spectrum antimicrobial activity by means of direct interactions with cellular or molecular targets of pathogens or indirectly by increasing the host immune response. Thus, due to the aforementioned properties, these agents might have a great potential in a clinical setting, not only to counteract SARS-CoV-2 infection, but also to prevent opportunistic infections in critically ill COVID-19 patients.

Medical infrared thermal imaging of syringomyelia in the Cavalier King Charles Spaniel.

BACKGROUND: Medical infrared thermal imaging (MITI) is a non-invasive imaging modality gaining popularity in the veterinary field. An infrared camera captures emission of heat and creates a color map in the form of a thermogram. Topical heat emission is influenced by localized disease processes as a result of autonomic nervous system imbalance. The purpose of this study was to determine the utility of using thermography to identify changes in thermographic patterns associated with syringomyelia (SM) presence or absence in Cavalier King Charles Spaniels (CKCS) with Chiari-like Malformation (CLM). RESULTS: In CKCS with CLM, MITI was most accurate at a texture distance of 6. Optimizing imaging feature sets produced a highest accuracy of 69.9% (95% CI: 59.5-79.0%), with 81.3% sensitivity and 57.8% specificity for identifying the presence of syringomyelia. CONCLUSION: Thermographic image analysis is a successful non-invasive, diagnostic test that can be used to screen for syringomyelia presence in a CKCS with CLM.

The American Student Placements in Rehabilitation Engineering Program (ASPIRE).

Background: American Student Placements and Internships in Rehabilitation Engineering is founded on the principal of sparking the interest in a new generation of rehabilitation engineering scientists to transform the lives of older adults and people with disabilities. Each year a minimum of 10 students were enrolled.Methods: The internship runs for 10 weeks and activities center on developing excitement about technology and engineering and understanding the principles and processes of conducting rehabilitation engineering research. This was accomplished by student participation in 1) rehabilitation engineering research projects; 2) educational research training, and 3) professional activities with clinical and engineering faculty, staff, and graduate students. Of the 162 participants, 53% were women and 47% men. 23% of participants were from minority or underrepresented groups, and 18% identified as having a disability.Results: From post-internship follow-up efforts, 65% of program participants went on to pursue or have graduated with advanced degrees, 27% of whom are engineers from underrepresented groups. Of those students that are working post-baccalaureate, 70% are engineers working in a biomedical/technology field. In the past 3 years, 92% of students stated that the program met or exceeded their expectations, while 100% of the 2018 group felt that their expectations were met.Conclusion: The American Student Placements and Internships in Rehabilitation Engineering program has demonstrated efficacy in preparing undergraduate students for future academic work and employment.Implications for RehabilitationCreative researchers and designers will lead the way in advancing accessibility standards and engineering for people with disabilities.The ASPIRE program increases excitement for and interest in the fields of rehabilitation engineering among undergraduate students to positively influence academic and professional careers.Students enrolled in the ASPIRE program actively participated in a real multidisciplinary project supervised by professor mentors. This led students to take a problem-based approach in their professional development.The ASPIRE program stimulates rehabilitation engineering in students' mindset and promotes inclusive academic environments and communities.Rehabilitation engineering is not a mainstream discipline, but the ASPIRE program indicates that there are benefits to student education, including participatory action engineering, that need to continue gain momentum until rehabilitation engineering is a mainstream discipline or a core component of engineering education.We must move beyond a "survival of the fittest" mentality. A "survival of the fittest" model places a disproportionate burden on groups that are underrepresented in science and engineering, and thereby postpones the day on which the demographics of science and engineering are comparable to that of society as a whole.The ASPIRE program needs to be replicated at various institutions around the world.

Medical infrared thermal imaging of canine appendicular bone neoplasia.

BACKGROUND: Medical infrared thermal imaging (MITI) is a noninvasive imaging modality used in veterinary medicine as a screening tool for musculoskeletal and neurological disease processes. An infrared camera measures the surface body heat and produces a color map that represents the heat distribution. Local trauma or disease can impair the autonomic nervous system, which leads to changes in the local dermal microcirculation and subsequent alteration of surface body heat. Disruption of autonomic flow to the cutaneous vasculature at deeper levels can also result in asymmetric thermographic results. The purpose of this study was to evaluate surface temperature differences between limbs affected by bone neoplasia and their normal contralateral limbs. RESULTS: A statistically significant difference in average temperature was noted between regions of interest of the two groups (paired difference: 0.53 C° ± 0.14; P = 0.0005). In addition, pattern recognition analysis yielded a 75-100% success rate in lesion identification. CONCLUSIONS: Significant alterations noted with average temperature and thermographic patterns indicate that MITI can document discernible changes associated with the presence of canine appendicular bone tumors. While MITI cannot be used as the sole diagnostic tool for bone cancer, it can be used as a screening modality and may be applicable in early detection of cancer.

Antimicrobial properties of the medicinal plant Cardiospermum halicacabum L: new evidence and future perspectives.

The emergence and rapid spread of multidrug-resistance in human pathogenic microorganisms urgently require the development of novel therapeutic strategies for the treatment of infectious diseases. From this perspective, the antimicrobial properties of the natural plant-derived products may represent an important alternative therapeutic option to synthetic drugs. Among medicinal plants, the Cardiospermum halicacabum L. (C. halicacabum), belonging to Sapindaceae family, could be a very promising candidate for its antimicrobial activity against a wide range of microorganisms, including both Gram-positive and Gram-negative bacteria, as well as fungal pathogens. Although the antimicrobial properties of C. halicacabum have been intensively studied, the mechanism/s by which it exerts the inhibitory activity towards the pathogenic microbes have not yet been completely understood. This review focuses on the main antimicrobial activities displayed in vitro by the plant extract, with particular attention on our recent advances. We demonstrated that C. halicacabum is able to exert in vitro a dose-dependent fungistatic effect against Trychophyton rubrum (T. rubrum) through molecular interaction with the fungal heat shock protein (Hsp)-90 chaperone. These findings are supported by a growing body of research indicating the crucial role played by the Hsp90 in the virulence of the pathogenic microorganisms, including fungal pathogens. The possible future use of C. halicacabum for treating a wide range of infectious diseases is also discussed.

Accessible machining for people who use wheelchairs.

Despite the Americans with Disabilities Act mandate for reasonable accommodations, wheelchair users are often placed in the role of observer and note-taker when learning machining and fabrication skills due to a lack of accessibility. The focus of this case study report is to identify and develop reasonable accommodations for wheelchair users in an academic machine shop environment to address accessibility limitations of original equipment manufacturer (OEM) machines. Individual wheelchair users working and learning within the Human Engineering Research Laboratories (HERL) were observed and interviewed about their experiences using the machine shop equipment without modifications, followed by further observations after accommodations were implemented.

"Shades of Gray" in pancreatic ductal adenocarcinoma: Reappraisals on resectability criteria: Debated indications for surgery in pancreatic cancer.

Pancreatic ductal adenocarcinoma is one of the leading causes of cancer-related deaths and, currently, surgery is the only curative treatment. Patients with borderline resectable pancreatic cancer (BRPC) can benefit from a multidisciplinary approach and R0 resection, and can achieve the same outcome as resectable patients treated with upfront surgery. However, the definition of BRPC changes according to different classifications with a heterogeneous distribution of patients, and it is thus difficult to compare clinical evidence. We performed a literature review to assess the most suitable classification of BRPC. Our review was conducted using the PubMed database. Only articles containing more than ten patients classified according to NCCN, MDACC or AHPBA/SSAT/SSO classifications were selected. A total of 16 studies were included in our analysis, and were grouped according to one of these three classifications. The total resection rate was 61.4%, with considerable differences between the groups (68.4% for NCCN, 54.9% for MDACC and 53.2% for AHPBA/SSO/SSAT). The total R0 resection rate was 90.1% (89.1% for NCCN, 92.5% for MDACC and 84% for AHPBA/SSO/SSAT). Of the three classifications, NCCN limits the use of confusing terms and uses restrictive criteria to define the most appropriate treatment for each subgroup. However, several reports have suggested that, even in the case of a limited disease, biological and clinical factors should be considered in order to classify patients as resectable. NCCN classification appears to be the classification that allows the highest percentage of patients with BRPC to achieve resection without reducing the R0 resection rate. The choice of therapy should not only be based on imaging results, but also on a wider clinical multidisciplinary evaluation.

Tadpoles of the horned frog Ceratophrys ornata exhibit high sensitivity to chlorpyrifos for conventional ecotoxicological and novel bioacoustic variables.

Previous studies reported that some species of the family Ceratophryidae are able to produce sounds during premetamorphic tadpole stages. We have now determined the effects of the cholinesterase-inhibiting insecticide chlorpyrifos (CPF) on sounds emitted by tadpoles of Ceratophrys ornata. Tadpoles were exposed individually in order to evaluate the progression of effects. Effects on sound production were complemented with common ecotoxicological endpoints (mortality, behavior, abnormalities and growth inhibition). C. ornata was found to be more sensitive than other native (= 67%, 50%) and non-native species (= 75%, 100%) considering lethal and sublethal endpoints, respectively. Effects on sounds appear along with alterations in swimming, followed by the presence of mild, then severe abnormalities and finally death. Therefore, sound production may be a good biomarker since it anticipates other endpoints that are also affected by CPF. Ceratophrys ornata is a promising new model species in ecotoxicology.

Occurrence and levels of glyphosate and AMPA in shallow lakes from the Pampean and Patagonian regions of Argentina.

Glyphosate (N-(phosphonomethyl)glycine) is a broad-spectrum systemic herbicide used to kill weeds that compete with commercial crops. In Argentina, the use of glyphosate-based herbicides increased dramatically (up to ∼200,000 tons on 2012) since the introduction of glyphosate-resistant crops, such as transgenic soy and resistant corn, and the adoption of non-till practices in the 1990's. Sallow lakes within the Pampa region may be potentially impacted by continuous herbicide usage. We surveyed 52 shallow lakes from the Pampa region (Buenos Aires Province, Argentina) to assess the occurrence and concentrations of glyphosate and its main degradation product (AMPA). For comparison, we also sampled 24 shallow lakes from an area with no agricultural use of glyphosate (Northern Patagonia). Glyphosate and AMPA were analyzed by UPLC-MS/MS ESI (±) in lake water, suspended particulate matter (SPM), and sediment samples. Within the Pampa region, glyphosate residues were detected in >40% of samples. Glyphosate residues were detected more frequently in sediment and surface water than in SPM samples. The mean (maximum) concentrations of glyphosate were 2.11 (4.52) µg l-1 for surface water; 0.10 (0.13) µg l-1 for SPM and 10.47 (20.34) µg kg-1 for sediment samples, respectively. Whereas, mean (maximum) concentrations of AMPA were 0.84 and (0.90) µg l-1 for surface water; 0.07 (0.07) µg l-1 for SPM; and 22.53 (32.89) µg kg-1 for sediment samples. The herbicide was not detected in samples from the Patagonian region. To our knowledge, this is the first study reporting the occurrence and concentrations of the herbicide in freshwater lakes of Argentina.

Sublethal effects in Perinereis gualpensis (Polychaeta: Nereididae) exposed to mercury-pyrene sediment mixture observed in a multipolluted estuary.

Sediment-living organisms can be subjected to a multi-pollution condition due to an increase in the diversity of contaminants. Sediment mixtures of Mercury (Hg) and some polycyclic aromatics hydrocarbons like Pyrene (Pyr) are common in heavily industrialized coastal zones. In the present study, greater than (>) and less than (<) probable effect concentration levels (PELs) of Hg and Pyr were assessed using spiked sediments in order to determine combined (Hg + Pyr) effects in uptake, metabolization and oxidative balance in the polychaete Perinereis gualpensis at short and medium-term exposure. Hg + Pyr significantly influenced the uptake/kinetics of Hg and Pyr metabolite 1-OH-pyrene in polychaete tissues during the exposure time compared with separate treatments of each analyte (p < 0.05). Both the Hg-only and Pyr-only exposures significantly influenced both enzymatic and non-enzymatic responses respect to control groups (p < 0.05). The Hg-only treatment showed the worst scenario related to the activation and subsequent inhibition of glutathione S- transferase (GST) and peroxidase (GPx) activities, high levels of Thiol-groups (SH-groups), low antioxidant capacity (ACAP) and enhanced lipid peroxidation (TBARS) in the last days of exposure (p < 0.05). In contrast, ragworms exposed to Hg + Pyr showed a significant increase in both enzymatic and non-enzymatic activity during the first days of exposure and the absence of lipid peroxidation during the whole experiment. Our results suggest different oxidative stress scenarios in P. gualpensis when exposed to >PEL Hg concentration with