Sedimentary organic carbon and nitrogen stocks of intertidal seagrass meadows in a dynamic and impacted wetland: Effects of coastal infrastructure constructions and meadow establishment time

Seagrass meadows, through their large capacity to sequester and store organic carbon in their sediments, contribute to mitigate climatic change. However, these ecosystems have experienced large losses and degradation worldwide due to anthropogenic and natural impacts and they are among the most threatened ecosystems on Earth. When a meadow is impacted, the vegetation is partial- or completely lost, and the sediment is exposed to the atmosphere or water column, resulting in the erosion and remineralisation of the carbon stored. This paper addresses the effects of the construction of coastal infrastructures on sediment properties, organic carbon, and total nitrogen stocks of intertidal seagrass meadows, as well as the size of such stocks in relation to meadow establishing time (recently and old established meadows). Three intertidal seagrass meadows impacted by coastal constructions (with 0% seagrass cover at present) and three adjacent non-impacted old-established meadows (with 100% seagrass cover at present) were studied along with an area of bare sediment and two recent-established seagrass meadows. We observed that the non-impacted areas presented 3-fold higher percentage of mud and 1.5 times higher sedimentary organic carbon stock than impacted areas. Although the impacted area was relatively small (0.05-0.07 ha), coastal infrastructures caused a significant reduction of the sedimentary carbon stock, between 1.1 and 2.2 Mg OC, and a total loss of the carbon sequestration capacity of the impacted meadow. We also found that the organic carbon stock and total nitrogen stock of the recent-established meadow were 30% lower than those of the old-established ones, indicating that OC and TN accumulation within the meadows is a continuous process, which has important consequences for conservation and restoration actions. These results contribute to understanding the spatial variability of blue carbon and nitrogen stocks in coastal systems highly impacted by urban development.

Post-intensive Care Unit COVID-19 Survivors: Functional Status and Respiratory Function Three Months After an Inpatient Rehabilitation Program

Introduction and objectives Long-term coronavirus disease 2019 (COVID-19) sequelae have become an increasing concern, with persistent dyspnoea and fatigue being the most common and long-lasting symptoms reported. The aim of this study was to evaluate the functional status and respiratory function three months after discharge from an inpatient rehabilitation program. Materials and methods This was a prospective study including post-ICU COVID-19 survivors consecutively admitted to an inpatient and multimodal rehabilitation program in a rehabilitation center. Evaluation of functional status (brief balance evaluation systems test (brief-BESTEST), timed up and go (TUG) test, 1 min sit to stand test (1STST), 6 min walking test (6MWT)); respiratory muscle strength (maximum expiratory pressure (MEP), maximum inspiratory pressure (MIP)); cough effectiveness (peak cough flow (PCF)); and fatigue (fatigue assessment scale (FAS)) were assessed at admission (T0), discharge (T1), and three months after discharge (T2). Results A total of 36 patients were included. Between T1 and T2, there was a significant improvement in MEP (84.47±20.89 vs 97.23±24.63 cmH₂O, p<0.001), PCF (367.83±117.24 vs 441.33±132.90 L/min, p=0.003), functional capacity (1STST (19.90±6.37 vs 23.13±6.07, p=0.004), and 6MWT (459.25±153.70 vs 500.00±163.74 meters, p=0.003)). No differences were seen in MIP, brief-BESTEST, or TUG. Patients presented a higher median final FAS score at T2 compared to T1: 21.50±5 vs 18.60±2.65, p=0.002. Conclusions Post-ICU COVID-19 survivors admitted to an inpatient rehabilitation program maintained a good functional recovery at the three-month follow-up. Despite overall improvement, we found higher scores of FAS, suggesting worse fatigue levels.

Oral Presentation No. 69 Chronotropic incompetence: still a suitable indicator?

Background

Chronotropic incompetence (CI) is defined as the inability to increase heart rate (HR) in response to increased activity. It is common in patients (pts) with cardiovascular (CV) disease, being a predictor of major adverse CV events; however, its importance is often underestimated in clinical practice.

Purpose

Evaluate the prognostic value of CI in pts with known coronary artery disease (CAD) who performed Bruce protocol treadmill testing.

Methods

Unicentric, retrospective analysis of consecutive pts with known CAD who underwent Bruce protocol treadmill testing between 2009 and 2010. Chronotropic index (ChI) was calculated as:(peak HR–resting HR)/(220–age–resting HR). CI was defined as ChI &lt; 80% (&lt; 62% in pts prescribed with beta-blockers). Pts were divided in two groups-G1: CI and G2: normal chronotropic response. Events were defined as: de novo heart failure (HF), CAD progression, myocardial infarction (MI), stroke, all-cause mortality and CV mortality.

Results

A total of 471 pts were included (87.3% male, mean age 69 ± 9.8 years). Mean follow-up was 9.7 years. The groups were similar regarding sex, age, body mass index, diabetes, arterial hypertension, dyslipidemia, MI and left ventricle ejection fraction (P &gt; 0.050). CI was identified in 27.4% pts. Comparing G1 vs. G2, no differences were found related to all-cause mortality, de novo HF, CAD progression, MI and stroke (P &gt; 0.050). However, statistically significant differences were found regarding CV mortality (P = 0.028).

Conclusion

CI is a simple an easily available parameter that shows a clear association with CV mortality in a long-term follow-up of pts with CAD.

Clinical Case 16—Intracoronary thrombus- a fatality to unmask

26-years-old man, occasional cannabis smoker, attended the emergency department due to chest pain and epigastralgia for the past 24h, after cannabis consumption. Electrocardiogram revealed ST-segment elevation with Q-waves in V3-V5 and inferior leads. Transthoracic echocardiogram presented: (1) cardiac chamber dilation; (2) severely reduced biventricular systolic function; (3) hypokinesia of left ventricle basal segments of the anterior, lateral and septal walls; (4) scar appearance of the posterior wall and ventricular apex; (5) apical thrombus. Emergent cardiac catheterization showed thrombus located at the medial and distal segments of the left anterior descending artery (LAD), occlusion of the first obtuse marginal (OM) artery and thrombus at the medial and distal segments of the right coronary artery. Angioplasty of the OM was unsuccessful and hypocoagulation was initiated. The patient started veno-arterial ECMO. Immunological study was normal. His clinical condition deteriorated with multiple organ dysfunction, and he died after 20 days. The autopsy revealed coronary atherosclerosis with fibrous plaques causing 80% stenosis of the LAD with two sub-occlusive thrombus, occlusion of the circumflex artery, 70% stenosis of the posterior descending artery, two areas of myocardial infarction and several intracardiac thrombus.

We aim to discuss the possible aetiologies for the thrombus formation. The association between cannabis and acute coronary syndromes has been reported and in cases of young adults with chest pain this diagnosis should be considered. Alternatively, our patient presented dilated cardiac chambers with scar walls and presence of intracardiac thrombus that could be the cause of systemic embolization in an undiagnosed dilated cardiomyopathy.

Cardiopulmonary exercise testing in Fontan patients: unmasking the secret of Super-Fontans

Background

Exercise capacity is usually reduced in Fontan patients, however there is a subset of patients who have normal exercise capacity and better outcomes, the “Super-Fontans”. The aim of this study was to characterize a cohort of Fontan patients undergoing cardiopulmonary exercise testing (CPET) and identify predictors of better functional capacity.

Methods

Single center retrospective analysis of consecutive Fontan patients aged &gt;10 years old who underwent CPET, between March 2018 and May 2021.

Peak respiratory exchange ratio1.05 defined maximal CPET. Peak VO2 (pVO2) as a percentage of its predicted value was used as reference value to stratify patients in tertiles.

Patients in 3rd tertile, with a percentage predicted pVO2 superior to 75%, were considered good-performers.

Blood tests and transthoracic echocardiogram (TTE) were performed on the same day. Additional data were collected from electronic charts.

Results

In total, 49 patients were included (mean age 19±7 years old, 67% male) with intra or extracardiac conduit implanted in mean 12±7 years prior to the CPET.

The most common primary diagnoses were tricuspid/pulmonary atresia (43%), followed by unbalanced complete AV septal defect (14%) and double inlet left ventricle (14%). 12 patients had a systemic right ventricle. All, except 5 patients, had preserved systolic ventricular function and 37% had moderate to severe AV regurgitation.

The majority had normal hemoglobin levels (median 15.6 g/dL), hepatic enzymes (median total bilirubin 0.8 mg/dL), renal function (median creatinine 0.8 mg/dL) and low NT-proBNP (median 122 pg/mL).

All patients had maximal CPET, median %VO2 at VT1 was 57% of peak and mean pVO2 was 66±14% of the predicted. Most patients (69%) showed exercise limitation due to cardiovascular cause, followed by O2 desaturation, present in 22% of CPETs. The age of Fontan completion was not associated with functional capacity (p=0.6).

The good-performer group comprised 13 patients (27%), all in sinus rhythm, of which 10 were physically active. Compared with the remainder, this group had higher VO2 at VT1 (18.7 vs. 14.6, p=0.01) and VO2 at VT2 (25.9 vs. 22.1, p=0.02), both in mL/kg/min. Also, peak heart rate (% predicted) (90 vs. 81, p=0.03) was higher in this subgroup – fig.1. Conversely, differences on TTE parameters (GLS and AV valve regurgitation) and blood biomarkers were not statistically significant. On multivariable analysis, no single variable predicted better functional capacity.

Conclusion

In our Fontan cohort, most patients had reduced exercise capacity, largely due to cardiovascular dysfunction. However, “Super-Fontans” stood out as they had a higher anaerobic threshold illustrating their better physical condition. These findings highlight the role of regular physical activity in Fontan patients as a cornerstone for better functional capacity.

Funding Acknowledgement

Type of funding sources: None.

Potential impact of replacing SCORE with SCORE-2 on risk classification and statin eligibility – a coronary calcium score correlation study

Background

Recently, the European Society of Cardiology issued new algorithms to estimate the 10-year risk of atherosclerotic cardiovascular disease (ASCVD), along with new age-specific thresholds to classify individuals as low-to-moderate, high, or very-high risk.

The aim of this study was to compare the latest SCORE-2 model with the older SCORE (Systematic COronary Risk Evaluation) in their ability to identify individuals with high coronary artery calcium score (CACS), and assess the relationship between potential eligibility for statin therapy and CACS.

Methods

Individuals 40–69 years old without diabetes or known ASCVD were identified in a single center registry of patients undergoing CACS and coronary CT angiography for suspected coronary artery disease. SCORE and SCORE-2 were calculated and used with each patient's untreated LDL-C values to assess eligibility for statin therapy. High CACS was defined as an Agatston score ≥100.

Results

A total of 389 pts (46% men, mean age 58±8 years) were included, of which 15% (n=60) were active smokers. The mean systolic blood pressure and untreated LDL-C values were 136±17 mmHg and 155±65 mg/dL, respectively.

The proportion of patients classified as low-to-moderate risk, high risk, and very high risk was 93%, 6% and 1% using the SCORE algorithm, and 42%, 44%, and 14% using SCORE-2, respectively. Overall, 218 patients (56%) would have their risk category revised upwards, while no patients would be downgraded.

The median CACS was 5 (IQR 0–71 AU), with 166 patients (43%) having CACS = 0, and 81 (21%) presenting CACS values ≥100.

SCORE and SCORE-2 showed similar discriminative power to identify patients with CACS ≥100 (C-statistic 0.77, 95% CI 0.71–0.82, vs. 0.75, 95% CI 0.69–0.80, P=0.109 for comparison]. The up-reclassification of risk conveyed by SCORE-2 affected patients across all categories of CACS (Fig. 1).

The proportion of patients in whom statin therapy would generally be indicated was higher with the SCORE-2 criteria vs. the SCORE algorithm (61% vs. 29%, respectively, p&lt;0.001). The broadening of potential indication for statin therapy spanned all categories of CACS, including patients with CACS = 0 (Fig. 2).

Conclusion

Even though the discriminative power of SCORE-2 is similar to the older SCORE, the introduction of age-specific thresholds results in the up-reclassification of risk in roughly half of the patients. The application of SCORE-2 will broaden statin eligibility overall, not only in patients with high atherosclerotic burden, but also in those with CACS = 0. These findings support the use of risk modifiers in selected patients to improve the effectiveness of statin therapy.

Funding Acknowledgement

Type of funding sources: None.

Use of coronary calcium score to refine the cardiovascular risk classification of the new SCORE2 and SCORE2-OP algorithms in patients undergoing coronary CT angiography

Introduction

Recently, the European Society of Cardiology issued new algorithms (SCORE-2 and SCORE2-OP) to estimate the 10-year risk of atherosclerotic cardiovascular disease (ASCVD). CACS has been shown to reclassify a significant proportion of patients when applied on top of several scores, but data on its use with these new algorithms are lacking.

The aim of this study was to assess the risk reassignment that can be attained by using CACS as a risk modifier of the SCORE-2 / SCORE2-OP classification, in patients referred for coronary CT angiography (CCTA).

Methods

Individuals without diabetes or known ASCVD were included in a single center registry of patients undergoing CCTA for suspected coronary artery disease (CAD). The 10-year risk of cardiovascular disease was calculated for each patient using SCORE-2 (ages 40–69) or SCORE2-OP (ages 70–89), and categorised as low-to-moderate, high, or very-high risk, according to guideline-recommended age-specific thresholds. CACS was considered to reclassify risk one level downward if = 0 in high or very-high risk patients, and reclassify risk upward if &gt;100 (or &gt;75th percentile) in those with low-to-moderate risk, or &gt;1000 in those with high-risk.

Results

A total of 529 patients (43% men, mean age 63±10 years) were included, of which 13% (n=69) were active smokers. The mean systolic blood pressure and non-HDL-C values were 137±18 mmHg and 140±37 mg/dL, respectively.

A total of 47 patients (9%) had obstructive CAD on CCTA, classifying them as very-high risk. In the remainder 482 patients without obstructive CAD, the median CACS was 8 (IQR 0–80 AU), with 194 patients (40%) having CACS = 0, and 111 (23%) presenting CACS values ≥100.

The proportion of patients classified as low-to-moderate risk, high risk, and very high risk was 36%, 46% and 19% using the SCORE-2 / SCORE2-OP algorithm.

Using CACS would reclassify 150 patients (31%): 107 patients (22%) downward, and 43 patients (9%) upward. The extent of risk reclassification conveyed by CACS was 33% in patients assessed with SCORE-2, and 25% with SCORE-2 OP (p=0.082). Overall, most of the risk reassignment (42%, n=93) would occur in patients originally classified as high-risk – Fig. 1.

At the time of testing, 32% (n=61) of patients with CACS = 0 were being treated with statins, whereas 52% (n=58) of those with CACS ≥100 were not.

Conclusion

Even when the most recent SCORE-2 / SCORE-2 OP algorithms are used, risk refinement with CACS leads to the reclassification of nearly one third of the patients undergoing CCTA, mostly from downgrading risk. This opportunistic use of CACS may be employed to improve the allocation of primary prevention therapies.

Funding Acknowledgement

Type of funding sources: None.

Combined nanometric and phylogenetic analysis of unique endocytic compartments in Giardia lamblia sheds light on the evolution of endocytosis in Metamonada

Background

Giardia lamblia, a parasitic protist of the Metamonada supergroup, has evolved one of the most diverged endocytic compartment systems investigated so far. Peripheral endocytic compartments, currently known as peripheral vesicles or vacuoles (PVs), perform bulk uptake of fluid phase material which is then digested and sorted either to the cell cytosol or back to the extracellular space.

Results

Here, we present a quantitative morphological characterization of these organelles using volumetric electron microscopy and super-resolution microscopy (SRM). We defined a morphological classification for the heterogenous population of PVs and performed a comparative analysis of PVs and endosome-like organelles in representatives of phylogenetically related taxa, Spironucleus spp. and Tritrichomonas foetus. To investigate the as-yet insufficiently understood connection between PVs and clathrin assemblies in G. lamblia, we further performed an in-depth search for two key elements of the endocytic machinery, clathrin heavy chain (CHC) and clathrin light chain (CLC), across different lineages in Metamonada. Our data point to the loss of a bona fide CLC in the last Fornicata common ancestor (LFCA) with the emergence of a protein analogous to CLC (GlACLC) in the Giardia genus. Finally, the location of clathrin in the various compartments was quantified.

Conclusions

Taken together, this provides the first comprehensive nanometric view of Giardia’s endocytic system architecture and sheds light on the evolution of GlACLC analogues in the Fornicata supergroup and, specific to Giardia, as a possible adaptation to the formation and maintenance of stable clathrin assemblies at PVs.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12915-022-01402-3.

Quantitative and Qualitative Approaches for Dental Age Assessment in Sub Adult Portuguese Population: European Regression Formula and Demirjian Stages

INTRODUCTION

Over the last decade, the criminal justice system among the European countries deals with a new group of people, the undocumented people. In the criminal field, most of the suspected claimed to be under the minor legal age according to the type of crime. The government of each European country is committed to protecting the children and vulnerable people. There are serious safety concerns since adults falsely claim to be minors and legal systems oppose to such claims. In this study, we have used different age assessment methods and some of them without accuracy.

OBJECTIVE

To meet the general considerations we developed a study using the current dental age assessment methods. Hence, for the Portuguese population, this study aims to validate the European regression formula between the ages of 6 and 15 years of age; to estimate the cut-off point for the age of 12 years, and to compare the quantitative approach of European regression formula with Demirjian's qualitative approach for age estimation.

MATERIAL AND METHODS

483 orthopantomograms were analysed using the European formula and Demirjian scoring stages. A new method, Model 2, was designed to better suit the Portuguese population.

RESULTS

The European formula: average age underestimation of 4.88 for the third quadrant and 4.04 months for the fourth quadrant; and a mean absolute error (MAE) of 10.93 and 10.68 months respectively. Demirjian method: average overestimation of 8.70 months, MAE of 12.85 months. In Model 2: MAE of 9.37 months for the third quadrant, and 9.28 months for the fourth quadrant. Both European formula and Demirjian method had an area under ROC curves results above 0.93. Discrepancy of sensitivity between methods for the specific cut-off point: 11.48. The results obtained in this study can be extrapolated to 87.33% of the Portuguese population.

CONCLUSIONS

The European regression formula can be applied for the Portuguese population, and seems to be more accurate than Demirjian's methodology in this population. Nevertheless, both European regression formula and Demirjian method present similarly suitable results in the classification of 12 years of age, although there is a noticeable discrepancy favouring the European regression formula. The European Formula when applied for criminal age assessment, independently of population, is mandatory to indicate to the judicial institutions, the sensitivity of the results.

Subarachnoid and subdural haematoma after attempted spinal anaesthesia for caesarean section

We report a case of a previously healthy patient who developed a vertebral canal haematoma in the subarachnoid and subdural spaces after a spinal puncture for elective caesarean section. Vertebral canal haematomas are rare. There are different mechanisms for haematoma formation, but coagulation disturbances and trauma, most often due to needle punctures, are the most important. Vertebral canal haematoma may warrant emergent surgical decompression. In this case report we discuss vertebral canal haematomas, including possible mechanisms, clinical diagnosis, imaging modalities, methods for management and advice for patients. We consider the possible association between a vertebral canal haematoma and non-steroidal anti-inflammatory drugs, and draw attention to an existing black box warning for ketorolac. In this case, we explain why a conservative approach was chosen with a good outcome. We also report the effect of this complication on the patient experience.

Phase III impact of telerehabilitation in patients with coronary heart disease

Funding Acknowledgements

Type of funding sources: None.

Introduction

Cardiac rehabilitation (CR) in coronary heart disease (CAD) has been shown to improve physical capability and health-related quality of life, reducing morbimortality. However, CR accessibility is still low and patient adherence remains poor. It has been hypothesized that using mobile applications to telemonitor exercise-based CR would increase patient adherence to CR, improving results. Hybrid cardiac telerehabilitation (HCTR) is a new concept that includes center and home interventions.

Objectives

Investigate the effects of HCTR program on improving physical activity, quality of life and reducing cardiovascular risk factors among patients with CAD 1 year after CR phase II.

Materials and methods

Longitudinal retrospective study with patients who attended phase 2 CR program (CRP) at a hospital center between august 2018-november 2020. They were divided in 2 groups: group 1 completed conventional CRP (CCRP), 12 weeks of monitored hospital physical exercise and educational sessions; group 2 participated on HCTR program (CCRP associated to a tele-monitorization platform consisting of a mobile application, MOVIDA.eros, with medical prescription of physical exercise and remote interaction). Group 2 maintained use of MOVIDA.eros on phase 3. Evaluations were performed on T0 – phase 2 onset, T1 – end of phase 2, T2 – 1 year after T1, with registration of age, gender, occupation, body mass index (BMI), exercise stress testing, echocardiogram (evaluation of left ventricular ejection fraction [LVEF]), LDL, HDL cholesterol, triglycerides, NTproBNP levels, and application of EuroQol-5D questionnaire (EQ5D), International Physical Activity Questionnaire – Short Form (IPAQ).

Statistical analysis was completed through software SPSS v28. p-values &lt;0.05 were considered statistically significant.

Results

We analyzed 68 patients, 46 on group 1 and 22 on group 2. Variable analysis revealed similar group characteristics, except for age (p=0.011) and LVEF (p=0.005). There was an association between HCTR adherence and occupation (p=0.002; greater proportion of intellectual professionals on group 2). We observed a significant IPAQ (p=0.018) and EQ-5D index (p=0.034) improvement between T0 to T1 in both groups, but only in group 2 persisted till T2. In exercise stress testing, both groups revealed an increase in METs at T1 and decrease at T2, without significant differences between them. Regarding lipid profile, HbA1c, NTproBNP and BMI, both groups improved from T0 to T1 maintaining it till T2 with no differences between them, however in group 2 HDL cholesterol levels were greater and HbA1c levels were lower than group 1. In both groups, LVEF increased from T0 to T1 and from T1 to T2 in both groups, with faster and higher improvement in group 2.

Conclusions

HCTR outperformed CCRP improving physical activity, patient quality of life, HDL cholesterol and faster improvement of LVEF. These findings encourage the use of a mobile platform in CR.

Sinister sinusitis

Two previously well Caucasian teenage girls with no significant travel or family history were admitted with sinusitis refractory to treatment with antibiotics. Both had progressive symptoms despite broad-spectrum antibiotics and developed involvement of other systems, ultimately requiring admission to the paediatric intensive care unit (PICU). They were subsequently diagnosed with the same condition and made an excellent recovery.The first girl, 14 years old, originally presented to her general practitioner with a sore throat, nasal congestion, and fever. Despite multiple courses of antibiotics over the following month she presented again multiple times with progressive symptoms including epistaxis, widespread myalgia and arthralgia, difficulty in breathing, haemoptysis, fatigue, and weight loss. Examination on admission found minimal discharge from her right tympanic membrane, ulcerated inferior turbinates with dried blood and yellow mucus in both nasal cavities, swollen tonsils without exudate, and an isolated aphthous ulcer on the tip of her tongue. She had small bilateral cervical lymph nodes. Examination of the cardiovascular system was unremarkable but on respiratory examination there was reduced air entry on the right side. Her abdomen was generally tender but soft with no organomegaly. A week into her admission she developed an oxygen requirement and increased work of breathing requiring intubation and ventilation.The second girl, 13 years old, presented to her local hospital with a 1-day history of epistaxis, right ear pain, and pain and swelling to the right periorbital tissues. Again, despite multiple courses of antibiotics, she had persistent symptoms and subsequently developed fever, fatigue, haemoptysis, and had a syncopal episode. She was admitted to her local district general hospital and, despite initial treatment, deteriorated over the following 2 weeks with persistent fever, new oxygen requirement, deteriorating renal function, and anaemia. She was transferred to a tertiary centre for respiratory support which escalated from Optiflow, through continuous then biphasic positive airway pressure, intubation and ventilation, and ultimately VV-ECMO.The investigations for both patients prior to admission to PICU at our centre are shown in table 1.

Loss of surficial sedimentary carbon stocks in seagrass meadows subjected to intensive clam harvesting

Seagrass carbon stocks are vulnerable to physical disturbance. We assessed the effect of clam harvesting on the organic carbon (C_org) stocks in surface sediments in four intertidal Zostera noltei meadows on the Iberian Atlantic coast (Spain and Portugal), by comparing undisturbed and harvested areas. We also monitored the spatial cover of the meadows throughout the growing season. Sedimentary C_org content and C_org stocks were about four times lower in intensively harvested areas than in control areas, but there were not differences between areas with low harvesting pressure and control areas. Reductions of 53-85% in sedimentary C_org stocks of Z. noltei meadows were caused by intensive clam harvesting. The effect of intensive clam harvesting on C_org stocks increased throughout the growing season, but the area covered by the seagrass increased from 21 to 37%, suggesting rapid recovery of seagrass canopies and potential recovery of sedimentary C_org stocks.

Anesthesia or seizure-like behavior? The effects of two Amazonian plants, Acmella oleracea and Piper alatabaccum in zebrafish (Danio rerio)

Abstract Currently, available fish anesthetics can produce important side effects, including respiratory arrest and distress. Easy-to-implement alternatives with low toxicity are needed to ensure fish health as well as to help artisanal fisheries and fish sellers in handling and transporting fishes, and native plants seems to be the best alternative. We aimed to implement an anesthetic protocol using crude ethanolic extracts from flowers and leaves of two Amazonian plants, the Acmella oleracea and Piper alatabaccum. We first tested the extracts for anesthesia, using the zebrafish as model. Even though in some treatments the animals apparently entered deep anesthesia, many of them presented aberrant behaviors and even died. Thus, we performed new experiments testing the extracts effects on seizure-like behaviors of the fish. Only the leaf extract of A. oleracea has potential effects for fish anesthesia. Both the flower extract from this plant and the leaf extract from P. alatabaccum induced seizure-like behavior in the animals. In conclusion, besides bringing a possible new anesthetic protocol for fish, our work draws attention for the neurotoxic effects the anesthetic solutions may cause, since several studies defend other Piper species as anesthetic for fish and A. oleracea flowers’ extract was already pointed as fish anesthetic.