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To balance the risks and benefits of fish consumption, selenium, fatty acids (DHA + EPA), and mercury in fishery products were determined. Analyzed products were canned tuna, frozen tuna (Thunnus albacares), smoked striped marlin (Tetrapturus audax), fresh Pacific sierra (Scomberomorus sierra), fresh dolphinfish (Coryphaena hippurus), fresh tilapia (Gerres cinereus), and fresh bullseye puffer (Sphoeroides annulatus). Mercury (μg g

We seek to evaluate the detection performance of a rapid primary screening tool of Covid-19 solely based on the cough sound from 8,380 clinically validated samples with laboratory molecular-test (2,339 Covid-19 positives and 6,041 Covid-19 negatives). Samples were clinically labeled according to the results and severity based on quantitative RT-PCR (qRT-PCR) analysis, cycle threshold, and lymphocytes count from the patients. Our proposed generic method is an algorithm based on Empirical Mode Decomposition (EMD) with subsequent classification based on a tensor of audio features and a deep artificial neural network classifier with convolutional layers called DeepCough'. Two different versions of DeepCough based on the number of tensor dimensions, i.e. DeepCough2D and DeepCough3D, have been investigated. These methods have been deployed in a multi-platform proof-of-concept Web App CoughDetect to administer this test anonymously. Covid-19 recognition results rates achieved a promising AUC (Area Under Curve) of 98.800.83%, sensitivity of 96.431.85%, and specificity of 96.201.74%, and 81.08%5.05% AUC for the recognition of three severity levels. Our proposed web tool and underpinning algorithm for the robust, fast, point-of-need identification of Covid-19 facilitates the rapid detection of the infection. We believe that it has the potential to significantly hamper the Covid-19 pandemic across the world.

The mitochondrial membrane potential (ΔΨm) is a parameter often used to determine mitochondrial function; therefore, it can be used to determine the integrity and functionality of cells. A decrement of ΔΨm is implicated in several inflammatory-related pathologies, such phenomena can be related to COVID-19 infection. The present work aimed to compare the ΔΨm in leucocytes (human PBMCs; HPBMC) isolated from healthy control (HC) subjects, patients with COVID-19 (C-19), recovered subjects at 40 ± 13 (R1) and 335 ± 20 (R2) days after infection (dai). Obtained data showed that ΔΨm decreased in HPBMC of subjects with C-19, R1, and R2 compared with HC. When analyzing the ΔΨm data by sex, in females, a significant decrease was observed in R1 and R2 groups versus HC. Regarding men, a significant decrease of ΔΨm was observed in R1, with respect to HC, contrary to R2 group, who reestablished this parameter. Obtained results suggest that the loss of ΔΨm could be related to the long-COVID.

A review of pesticide residues detected in shrimp species of the Mexican Pacific and Gulf of Mexico coasts is presented. Most studies focus on monitoring organochlorine (OC) and organophosphate (OP) pesticides. The evaluated areas are mainly located in the northwestern zone of Mexico. Studies analyzing pesticides levels in shrimp of Mexico correspond to commercially important species, such as: Penaeus vannamei, Penaeus stylirostris, Farfantepenaeus duorarum, and Trachypenaeus similis pacificus. Extraction methods (sample preparation, extraction technique, solvent, and clean-up procedures) are presented, as well as chromatography and detector type used to quantify the analytes in the shrimp samples from the different ecosystems evaluated. Given that there is an under-evaluation of pesticides residues presence, there was a greater contribution of studies directed to geographical areas in the northwest of the country, with a monitoring gap in the Gulf of Mexico, as well as in the southern zone, considering that there are states that are among the main shrimp-producing entities. Hence, it is necessary to carry out recent evaluations, since the most current information is 17 years out of date, so presented data may not be a reflection of the current situation in the country.

The first documented cases of Coronavirus disease of 2019 (COVID-19) in Wuhan city (Hubei province, China) were caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), studies mention viral transmission is more common in indoor and poorly ventilated environments compared to outdoor environments or environments with abundant airflow. In this context, this research aimed to estimate, through a mathematical model by a Box-Behnken design, the time and occupancy required in a physical space to reach CO2 levels that exceed the risk level established as a safer condition of 700 ppm for SARS-CoV-2 transmission. According to the proposed mathematical model, it is possible to predict safe conditions. With this, it was found that natural ventilation is the best option to reduce CO2 concentration, considering the occupancy/m3 and time, allowing a constant airflow; the use of air conditioners to control the temperature in rooms without natural ventilation is suggested; notwithstanding, these types of equipment are not designed to reduce CO2 concentration. Thus, their use in rooms with open windows and doors leads to a shorter equipment lifetime, for this reason, its operation in special conditions, such as in rooms without natural ventilation should be considered.

COVID-19 is a worldwide health emergency, therapy for this disease is based on antiviral drugs and immunomodulators, however, there is no treatment to effectively reduce the COVID-19 mortality rate. Fucoidan is a polysaccharide obtained from marine brown algae, with anti-inflammatory, antiviral, and immune-enhancing properties, thus, fucoidan may be used as an alternative treatment (complementary to prescribed medical therapy) for the recovery of COVID-19. This work aimed to determine the effects of ex-vivo treatment with fucoidan on cytotoxicity, apoptosis, necrosis, and senescence, besides functional parameters of calcium flux and mitochondrial membrane potential (ΔΨm) on human peripheral blood mononuclear cells isolated from SARS-CoV-2 infected, recovered and healthy subjects. Data suggest that fucoidan does not exert cytotoxicity or senescence, however, it induces the increment of intracellular calcium flux. Additionally, fucoidan promotes recovery of ΔΨm in PBMCs from COVID-19 recovered females. Data suggest that fucoidan could ameliorate the immune response in COVID-19 patients.

Diazinon is an organophosphorus pesticide, which may have potential toxic effects on the liver and immune system; however, the underlying mechanisms remain mostly unidentified. This work is aimed at evaluating the oxidative stress and cell cycle alterations elicited by low-dose diazinon in a rat liver cell line (BRL-3A) and spleen mononuclear cells (SMC) from Wistar rats. Diazinon (10-50 μM) caused early reactive oxygen species (ROS) generation (from 4 h) as well as increased O

OBJECTIVE: To perform an improved large-scale SARS-CoV-2 detection on pooled tests of asymptomatic workers. METHODS: qRT-PCR validation of the SARS-CoV-2 detection in salivae samples and saliva pools and working-group saliva pooling and testing for SARS-CoV-2. RESULTS: We found a high Cycle threshold (Ct) correlation (r = 0.9099) between swabs and saliva samples. Then, through the pooling strategy, we detected that 18/360 (5%) of individual saliva samples were SARS-CoV-2 positive. Saliva-pooling efficiency (360 of test sample/30 individual PCR) was higher (5.45) than the reported for swabbing group-testing and we spared 82% of the PCR reagents as well as sampling and personal protection equipment. CONCLUSION: Through this simplified and less expensive procedure, we detected in a short time asymptomatic-infected SARS-CoV-2-carriers that were isolated from their co-workers, thus, this methodology can be implemented in different workplaces to ensure consumers that employees are not infectious.

Organophosphate pesticides as diazinon disrupt the neuroimmune communication, affecting the innate and adaptive immune response of the exposed organisms. Since the target molecule of diazinon is typically the acetylcholinesterase enzyme (AChE), the existence of a non-neuronal cholinergic system in leukocytes makes them susceptible to alterations by diazinon. Therefore, the aim of this work was to evaluate the activity of AChE, acetylcholine (ACh) concentration, and the expression of nicotinic ACh receptors (nAChR) and muscarinic ACh receptors (mAChR) in spleen mononuclear cells (SMNC) of Nile tilapia (O. niloticus) exposed in vitro to diazoxon, a diazinon metabolite. SMNC were exposed in-vitro to 1 nM, 1 μM, and 10 μM diazoxon for 24 h. The enzyme activity of AChE was then evaluated by spectrophotometry, followed by ACh quantification by ultra-performance liquid chromatography. Finally, mAChR and nAChR expression was evaluated by RT-qPCR. The results indicate that AChE levels are significantly inhibited at 1 and 10 μM diazoxon, while the relative expression of (M3, M4, and M5) mAChR and (β2) nAChR is reduced significantly as compared against SMNC not exposed to diazoxon. However, ACh levels show no significant difference with respect to the control group. The data indicate that diazoxon directly alters elements in the cholinergic system of SMNC by AChE inhibition or indirectly through the interaction with AChR, which is likely related to the immunotoxic properties of diazinon and its metabolites.

BACKGROUND Major depressive disorder (MDD) is a global health issue that affects 350 million people of all ages. Although between 2% and 5.6% of affected individuals are adolescents, research on young patients is limited. The inflammatory response contributes to the onset of depression, and in adult MDD patients, symptom severity has been linked to chemokine levels. AIM To determine the differences in circulatory levels of chemokines in healthy volunteers (HVs) and adolescents with MDD, and assess the changes induced by fluoxetine consume. METHODS The 22 adolescents with MDD were monitored during the first 8 wk of clinical follow-up and clinical psychiatric evaluation was done using the Hamilton depresión rating scale (HDRS). The serum levels of monocyte chemoattractant protein-1 (MCP-1), macrophage inflammatory protein (MIP)-1α, MIP-1β, interleukin (IL)-8, interferon gamma-induced protein (IP)-10, and eotaxin were measured in patients and HVs. RESULTS In all cases, significant differences were detected in circulating chemokine levels between patients before treatment and HVs (P < 0.0001). All chemokines decreased at 4 wk, but only MCP-1 and IL-8 significantly differed (P < 0.05) between 0 wk and 4 wk. In the patients, all chemokines rose to their initial concentrations by 8 wk vs 0 wk, but only IP-10 did so significantly (P < 0.05). All patients experienced a significant decrease in HDRS scores at 4 wk (P < 0.0001) and 8 wk (P < 0.0001) compared with 0 wk. CONCLUSION Despite the consumption of fluoxetine, patients had significantly higher chemokine levels, even after considering the improvement in HDRS score. The high levels of eotaxin, IP-10, and IL-8 partially explain certain aspects that are affected in MDD such as cognition, memory, and learning.

Temephos and spinosad are pesticides used for control of vector-borne diseases such as dengue, chikungunya and zika. However, the inadequate use of these substances has affected the health of non-t...

Governments have implemented measures to minimize SARS-CoV-2 spread. However, these measures were relaxed, and the appearance of new variants has prompted periods of high contagion known as waves. In Mexico, four waves distributed between July and August 2020, January and February 2021, August and September 2021, and January and February 2022 have appeared. Current health policies discourage mass sampling, preferring to focus on the corrective treatment of severe cases. Outpatients are only advised to undergo brief voluntary confinement and symptomatic treatment, with no follow-up. Therefore, the present study aimed to analyze sex, age, and viral load in outpatients during the four waves in a medium-sized city in Mexico. For each wave, the date of peak contagion was identified, and data were collected within ±15 days. In this regard, data from 916 patients (434 men and 482 women) were analyzed. The age range of positive patients (37–45 years) presented a higher frequency during the first and third waves, while 28–36 years was the most frequent age range during the second and fourth waves, while the viral load values were significantly higher, for both sexes, during the fourth wave. Obtained data of COVID-19 prevalence in population segments can be used for decision-making in the design of effective public health policies.

Organophosphorus pesticides (OPs) are widespread insecticides used for pest control in agricultural activities and the control of the vectors of human and animal diseases. However, OPs’ neurotoxic mechanism involves cholinergic components, which, beyond being involved in the transmission of neuronal signals, also influence the activity of cytokines and other pro-inflammatory molecules; thus, acute and chronic exposure to OPs may be related to the development of chronic degenerative pathologies and other inflammatory diseases. The present article reviews and discusses the experimental evidence linking inflammatory process with OP-induced cholinergic dysregulation, emphasizing the molecular mechanisms related to the role of cytokines and cellular alterations in humans and other animal models, and possible therapeutic targets to inhibit inflammation.

Organophosphate pesticides (OPs) have greatly facilitated food production worldwide, and their use is not limited to agriculture and the control of pests and disease vectors. However, these substances can directly affect the immune response of non-target organisms. In this sense, exposure to OPs can have negative effects on innate and adaptive immunity, promoting deregulation in humoral and cellular processes such as phagocytosis, cytokine expression, antibody production, cell proliferation, and differentiation, which are crucial mechanisms for host defense against external agents. This review focuses on the scientific evidence of exposure to OPs and their toxic effects on the immune system of non-target organisms (invertebrates and vertebrates) from a descriptive perspective of the immuno-toxic mechanisms associated with susceptibility to the development of bacterial, viral, and fungal infectious diseases. During the exhaustive review, we found that there is an important gap in the study of non-target organisms, examples of which are echinoderms and chondrichthyans. It is therefore important to increase the number of studies on other species directly or indirectly affected by Ops, to assess the degree of impact at the individual level and how this affects higher levels, such as populations and ecosystems.

Diazinon is an organophosphate insecticide commonly used worldwide to chemically control different organisms considered as pests. In the past years, diazinon has been described to have immunotoxic effects in several species. Nile tilapia is a teleost fish with an ecological and economic importance, which is also one of the fishes with the highest consumption around the world. The aim of this study was to evaluate the production of neutrophil extracellular traps (NETs) from fish Nile tilapia (Oreochromis niloticus) exposed to diazinon (0.97, 1.95, and 3.91 mg/L) for 6 and 24 h. The results obtained indicate that the exposure to diazinon per se increases NETs production. Therefore, these results could be involved in the understanding of the inflammatory process induced by exposure to pesticides.

Diazinon (DZN) is an organophosphate pesticide characterized by inhibiting the enzyme acetylcholinesterase (AChE) (E.C. 3.1.1.7), affecting the nervous system. There is currently enough evidence proving this pesticide also affects the immune response; however, the immunotoxicity mechanisms through which these substances exerts toxic effects remain unclear. For that reason, this work evaluated the effect of diazinon on the intracellular calcium flux, ERK1/2 phosphorylation (pERK1/2), apoptosis, senescence, and mitochondrial membrane potential (ΔΨm) in spleen mononuclear cells (SMNC) of Nile tilapia, a teleost fish of commercial and ecological relevance. The results obtained indicate that diazinon causes significant damage in all evaluated parameters, which play an essential role in intracytoplasmic signaling of immune cells, suggesting these signal pathways could be related with the immunotoxicity mechanism of these type of pesticides.

Breast cancer treatment failure is related to low response rates, high costs, and long-term toxicities. Thus, it is necessary to find less toxic, cheaper, and more effective treatments. In situ administration ensures drug delivery to tumor cells and decreases systemic toxic effects. The androstene-3β, 17α-diol (α-AED) reduces breast tumor cell proliferation and is an ideal candidate to treat mammary tumors. This study aims to identify the in vitro and in vivo effects of α-AED on a triple-negative mammary tumor model. An in vitro biphasic steroid effect was observed in mouse and human mammary tumor cells treated with α-AED. In this sense, cells treated with higher doses (100 and 200 μM) showed an antiproliferative effect. The α-AED administrated intratumorally reduced average tumor weight and increased the percentage of natural killer cells (NK), plasmatic, and plasmablast cells in mice tumors. Of note, VEGF levels in all α-AED-treated tumors was lower than in the control and vehicle groups. The tumor in situ increased response was reflected systemically by higher anti-4T1 IgG concentration in serum from α-AED-treated mice, but no other associated systemic changes were detected. The reduction in tumor size for the local injection of α-AED is associated with the anti-proliferative effect of this steroid, and the lower local levels of VEGF may be related to the imperceptible macroscopic metastasis in α-AED-treated mice. The above suggests that α-AED may be used in clinical studies to prove its efficacy as an alternative breast tumor treatment or in conjunction with already established therapies.

Introduction Former studies have shown that hematologic parameters are affected by the SARS‐CoV‐2 infection which has caused a global health problem. Therefore, this research aims to identify the most frequent symptoms and comorbidities in SARS‐CoV‐2 infected outpatients; besides, to analyze hematological parameters and their correlation with cycle threshold (Ct) values. Methods We analyzed a total of sixty outpatients with SARS‐CoV‐2 infection. They were divided according to sex. Afterward, a questionnaire was carried out to find out their symptoms and comorbidities. Additionally, blood biometry data were correlated with the Ct value, respectively. Results Sixty patients were analyzed; the mean age was 43 years. All patients were from Nayarit, Mexico. The frequency index showed that the main symptoms were headache and anosmia, and the comorbidities were obesity and smoking. The analysis of blood biometry showed a clear increase in red blood cells (RBC) related parameters in women. In both sexes an increase in the number of white blood cells (WBC) was observed. Also, all the hematological alterations correlated with the grade of infection. Conclusion Headache and anosmia are the most common symptoms according to the frequency index, the main comorbidities were obesity and smoking. Also, there is a Ct value correlation with hematological parameters (WBC, mean corpuscular volume, mean corpuscular hemoglobin, hemoglobin); they can be used as a prognostic marker of infection.

Cysticercosis is a disease caused by the metacestode of the parasite Taenia solium (T. solium). In humans, the most severe complication of the disease is neurocysticercosis. The drug of choice to treat this disease is albendazole; however, the bioavailability and efficacy of the drug are variable. Therefore, new molecules with therapeutic effects against this and other parasitic infections caused by helminths must be developed. Naphthoquinones are naphthalene-derived compounds that possess antibacterial, antifungal, antitumoral, and antiparasitic properties. The aim of this work was to evaluate the in vitro anti-helminthic effect of 2-[(3-chlorophenylamino)phenylmethyl]-3-hydroxy-1,4-naphthoquinone, isolated from a natural source and then synthesized (naphthoquinone 4a), using an experimental model of murine cysticercosis caused by Taenia crassiceps (T. crassiceps). This compound causes paralysis in the cysticerci membrane from day 3 of the in vitro treatment. Additionally, it induces changes in the shape, size, and appearance of the cysticerci and a decrease in the reproduction rate. In conclusion, naphthoquinone 4a has in vitro cysticidal activity on T. crassiceps cysticerci depending on the duration of the treatment and the concentration of the compound. Therefore, it is a promising drug candidate to be used in T. crassiceps and possibly T. solium infections.

The cells of the immune and neuronal systems share different receptors for cytokines or neurotransmitters, producing feedback responses between both systems. Cytokines such as IL-1β and TNF-α can induce inflammation; however, the secretion of these molecules can be modulated by anti-inflammatory cytokines, as is the case for TGF-β, as well as by different hormones or neurotransmitters such as the γ-aminobutyric acid (GABA). In this study, we evaluated the secretion of IL-1β, TNF-α, and TGF-β under basal conditions, in the head of the kidney, spleen, thymus, and serum of the Nile tilapia, as well as their release induced by different sub-basal increases of GABA. We found that at the higher dose of GABA these cytokines were synthesised at a higher concentration compared to the control group. These results may suggest that there is feedback between both systems and that GABA plays a role in the modulation of the immune response.

Spinosad and temefos are widely used pesticides for chemical control of dengue vector-borne disease (Aedes aegypti). The aim of this study was to compare the effect of acute exposure (7 days) to sp...

The immune response of teleosts (bonefish) is altered by diazinon (DZN), an organophosphate pesticide. It has been suggested that such alteration is due to the extraneuronal cholinergic system in fish leukocytes that renders these cells a target of pesticides. Diazoxon (DZO), the oxon metabolite of DZN, has been attributed immunotoxic effects. Still, to date there are no reports on the effects of DZO upon parameters involved in the signaling cascade of immune response cells. Therefore, this work evaluated the effect of DZO on key parameters of cell signaling (intracellular Ca2+ flux, ERK 1/2 phosphorylation), cell proliferation, and antiproliferative processes (apoptosis, senescence, mitochondrial membrane potential) in spleen mononuclear cells of Nile tilapia fish. The results obtained show that DZO does not affect cell proliferation but causes a lack of response to stimulation with PMA and ionomycin to release intracellular calcium. In addition, it inhibits ERK 1/2 phosphorylation and causes loss of mitochondrial membrane potential, apoptosis, and senescence. These results suggest that the lack of cell response to release intracytoplasmic Ca2+ inhibits ERK which disrupts the mitochondrial membrane potential, leading to cell apoptosis and senescence. These findings prove that DZO significantly affects key parameters involved in the survival of immune response cells.

The COVID-19 pandemic highlighted health systems vulnerabilities, as well as thoughtlessness by governments and society. Due to the nature of this contingency, the use of geographic information systems (GIS) is essential to understand the SARS-CoV-2 distribution dynamics within a defined geographic area. This work was performed in Tepic, a medium-sized city in Mexico. The residence of 834 COVID-19 infected individuals was georeferenced and categorized by viral load (Ct). The analysis took place during the maximum contagion of the first four waves of COVID-19 in Mexico, analyzing 158, 254, 143, and 279 cases in each wave respectively. Then heatmaps were built and categorized into five areas ranging from very low to very high risk of contagion, finding that the second wave exhibited a greater number of cases with a high viral load. Additionally, a spatial analysis was performed to measure urban areas with a higher risk of contagion, during this wave this area had 19,203.08 km2 (36.11% of the city). Therefore, a kernel density spatial model integrated by meaningful variables such as the number of infected subjects, viral load, and place of residence in cities, to establish geographic zones with different degrees of infection risk, could be useful for decision-making in future epidemic events.

Spinosad and temephos are two of the most used pesticides in Mexico for the control of vector causing disease such as dengue, chikungunya and Zika. The aim of this study was to compare the neurotoxic effects of these two pesticides using guppy fish (Poecilia reticulata) as a model organism. Guppies were exposed for 7 and 21 days to technical grade temephos and spinosad at 1.0 and 0.07 g/L, respectively, (10 and 0.5 mg/L of active substance; concentrations recommended by the Ministery of Health of the State (Secretaría de Salud de Nayarit (SSN) Mexico)). Subsequently, acetylcholinesterase activity (AChE) and acetylcholine concentrations (ACh) in muscle tissue were determined. Temephos exposure decreased AChE activity and increased ACh concentration, whereas exposure to spinosad only increased ACh concentration. Though cholinergic alterations were more severe in fish exposed to temephos, both pesticides were equally lethal during the first seven days after exposure. Nonetheless, temephos was more lethal after 21 days.

Major depressive disorder (MDD) has a prevalence of 5% in adolescents. Several studies have described the association between the inflammatory response and MDD, but little is known about the relationship between MDD and growth factors, such as IL-7, IL-9, IL-17A, VEGF, basic FGF, G-CSF, and GM-CSF. It must be appointed that there are scarce reports on growth factors in adolescents with MDD and even fewer with a clinical follow-up. In this work, we evaluated the levels of growth factors (IL-7, IL-9, IL-17A, VEGF, basic FGF, G-CSF, and GM-CSF) in MDD adolescents and the clinical follow-up during eight weeks of treatment with fluoxetine. Methods. All patients were diagnosed according to the DSM-IV-TR, and the severity of the symptoms was evaluated using the Hamilton Depression Rating Scale (HDRS). Growth factors IL-7, IL-9, IL-17A, VEGF, basic FGF, G-CSF, and GM-CSF were quantified by cytometric bead array using serum samples from 22 adolescents with MDD and 18 healthy volunteers. Results. All patients showed clinical improvement since the fourth week of pharmacological treatment according to the HDRS. Considerably higher levels of IL-7, IL-9, IL-17A, VEGF, basic FGF, G-CSF, and GM-CSF were detected in MDD adolescents as compared to healthy volunteers. A significant but temporal decrease was detected in basic FGF, G-CSF, and GM-CSF at week four of fluoxetine administration. Conclusions. To the best of our knowledge, this is the first report to show alterations in the levels of growth factors, such as IL-7, IL-9, IL-17A, VEGF, basic FGF, G-CSF, and GM-CSF in MDD adolescents during eight weeks of clinical follow-up. These disturbances might be involved in the physiopathology of MDD since such growth factors have been proven to participate in the neural development and correct functioning of the CNS; therefore, subtle alterations in it may contribute to MDD.

Bisphenol A, a very widespread environmental pollutant and endocrine disruptor compound, can interact with several steroid receptors, particularly with estrogen ones. In different studies, it has observed that the endocrine disruption during critical periods of development can trigger alterations in the immune response during the adult life. Male Wistar rats were exposed indirectly to BPA at a dose of 250 μg/kg day during the perinatal period (from day 5 of pregnancy until day 21 postnatal), At the 60 days of age, the adulthood, animals were infected with larvated eggs of the Toxocara canis, and were sacrificed at 7 days post-infection. Parasitic loads in the lung and in the liver were analyzed by artificial digestion. Furthermore, immune cell subpopulations (macrophages, NK cells, Tγδ, total T cells, T helper, T cytotoxic, and B lymphocytes) present in spleen, peripheral and mesenteric lymph nodes were analyzed by flow cytometry. The expression of Th1 and Th2 cytokines at the splenic level was determined by real-time quantitative PCR. Finally, the titers of specific antibodies against to the parasite were analyzed by ELISA. The BPA treatment administrated in the perinatally stage favors a significant increase of the percentage of Toxocara canis larvae in the lungs and liver in the adulthood. Additionally, the exposure to this compound caused a dramatically decrease in the production of specific antibodies against to this parasite, downregulating together Th2 cytokines (IL-4, IL-5 and IL-13), meanwhile upregulated Th1 cytokines (IFN-γ and TNF-α). Perinatal exposure to BPA affects the performance of the immune response during adult life, modifying both cytokines and antibodies production by these cells, which favors the susceptibility to infections, specifically toxocariosis.

Agricultural activity demands the use of pesticides for plague control and extermination. In that matter, diazinon is one of the most widely used organophosphorus pesticides (OPs). Despite its benefits, the use of OPs in agricultural activities can also have negative effects since the excessive use of these substances can represent a major contamination problem for water bodies and organisms that inhabit them. The aim of this paper was to evaluate oxidative damage in lipids and proteins of Nile tilapia (Oreochromis niloticus) exposed acutely to diazinon (0.97, 1.95 and 3.95 ppm) for 12 or 24 h. The evaluation of oxidative damage was determined by quantifying lipid hydroperoxides (Fox method) and oxidized proteins (DNPH method). The data from this study suggest that diazinon induces a concentration-dependent oxidative damage in proteins, but not lipids, of the liver and gills of Nile tilapia. Furthermore, the treatment leads to a decrease in the concentration of total proteins, which can have serious consequences in cell physiology and fish development.

Boca de Camichin Estuary is one of the main producers of Crassostrea corteziensis oysters in Mexico, but the presence of pollutants can affect oyster production. Molluscs produce reactive oxygen species (ROS) in response to changes in the environment and pollution. These ROS induce oxidative damage in biomolecules. The main objective of this study was to evaluate pollution in the estuary and the subsequent oxidative stress in C. corteziensis oysters during the 2010 production cycle. For this aim, we performed monthly samplings in the oyster farms from January to May. We took water samples to quantify polycyclic aromatic hydrocarbon (PAH) and metal content; also, we evaluated oxidative damage (lipoperoxidation, lipidic hydroperoxides, protein oxidation) and enzyme activity (CAT, SOD, GPx, GST and AChE) in oyster gills. The results show the presence of Cu, Fe, Mn, naphthalene, benz[a]anthracene, pyrene, benz[a]pyrene and benzo[k]fluoranthene. On the other hand, AChE activity was not inhibited, which suggests that organophosphorus pollutants or carbamates were absent. Regarding oxidative stress, oysters from the estuary had oxidative damage in lipids, not proteins, and altered antioxidant enzyme activity, when compared to control organisms. Interestingly, we did not observe any correlation between the pollutants and the oxidative stress parameters evaluated in this study. Thus, we cannot rule out that a synergistic effect between the environmental variables and the pollutants is causing the oxidative stress in these oysters.

Nervous and immune systems maintain a bidirectional communication, expressing receptors for neurotransmitters and cytokines. Despite being well established in mammals, this has been poorly described in lower vertebrates as fishes. Experimental evidence shows that the neurotransmitter acetylcholine (ACh) regulates the immune response. In this research, we evaluated mRNA levels of muscarinic acetylcholine receptor (mAChR) in spleen mononuclear cells of Nile tilapia (Oreochromis niloticus) and compared the expression levels of immune cells with the brain. The mAChR subtypes (M2-M5A) were detected in both tissues, but mAChRs mRNA levels were higher in immune cells. This data have a potential use in biomedical and comparative immunology fields.

Organophosphorus pesticides (OPs) are broad-spectrum insecticides. One of the commonly used OPs is diazinon (DZN). The aim of this study was to evaluate the immunotoxic effect of DZN on phagocytic parameters of blood leukocytes using the teleost fish Oreochromis niloticus as a study model. For this purpose, fish were exposed in vivo to 0.97, 1.95 and 3.97 mg/L of DZN for 6 and 24 h. Our results indicated that phagocytic active cells decreased in fish exposed in vivo to 0.97 and 1.95 mg/L of DZN for 6 and 24 h. Regarding ROS production, H2O2 and O2− levels were higher on fish exposed to 1.95 mg/L for 6 and 24 h, while H2O2 production increased at 0.97 mg/L for 24 h. From this we can conclude that phagocytic parameters are sensitive to assess the effect of acute intoxication with organophosphorus pesticides on Nile tilapia.

Biomarkers of pesticide toxicity and paraoxonase 1 (PON1) phenotype and genotypes were evaluated in indigenous Mexican farmworkers exposed mainly to organophosphate (OP) pesticides.Acetylcholinesterase, butyrylcholinesterase, and PON1 activities--arylesterase and CMPAase activities--were evaluated spectrophotometrically. PON1 55 and 192 polymorphisms were determined by real-time polymerase chain reaction. Hematological parameters were evaluated using a cytometer.Butyrylcholinesterase and arylesterase activities were lower in farmworkers, who also showed lower levels of leukocytes but higher percentages of lymphocytes when compared with the nonexposed group. Our results showed a high frequency of OP, high hydrolysis-related PON1 alleles (LL/QR and LL/RR) in the study population. An association was observed between CMPAase activity and PON1Q192R polymorphism.Our results suggest that pesticide exposure modifies biochemical and hematological biomarkers in the study population, and that the phenotype of PON1 (CMPAase) is a sensible susceptibility biomarker of OP pesticide toxicity.

Bisphenol A (BPA) is an endocrine disruptor to which animals and humans are highly exposed. Many reports have established a relationship between BPA exposure and breast cancer incidence, especially during critical periods of development. However, its effects on the immune response in testicular tumour growth have not yet been described. Thus, we wanted to analyse the effect of perinatal BPA exposure in pregnant female mice and the immune response modulation and tumour growth in an intratesticular cancer model in offspring male mice. Pregnant female mice were exposed to a dose of 250 mg/kg/day/body weight of BPA in their drinking water. In adulthood, male offspring underwent intrascrotal inoculation with 4T1 cancer cells. On day 21 after inoculation, mice were euthanised, and serum was obtained to measure BPA levels using HPLC coupled to mass spectrometry. The percentages of immune cell populations in peripheral lymph nodes (PLN), the spleen and tumours were evaluated by flow cytometry. In addition, the tumour expression of IL-10, TNF-&alpha, and TGF-&beta, was analysed by RT-PCR. Of note, we found detectable circulating levels of BPA in the offspring of mothers exposed to it while pregnant. Remarkably, BPA treatment promoted tumour growth by about 75% compared to mice coming from female mice that did not receive the compound. Perinatal exposure to BPA modulated the percentages of different immune cells in the spleen and PLN. In addition, the expression of inflammatory-related cytokines (IL-10 and TNF-&alpha, ) in the tumours was significantly enhanced compared to control and vehicle groups. In conclusion, the perinatal BPA administration in pregnant female mice modulated different cellular and molecular immune components that resulted in outstanding testicular tumour size in male offspring.

A survey of fungal contamination and presence of aflatoxins (AFs) and fumonisins (FBs) in 30 feed samples collected from 10 tilapia farms during three seasons in Nayarit State, located in north-western Mexico, was carried out using ELISA as screening and High-Performance Liquid Chromatography (HPLC) as confirmatory method. Mycobiota included Aspergillus flavus and Fusarium spp. AFs were detected in 63.3% of samples using ELISA, but confirmation by HPLC revealed that all samples were under the detection limit. Regarding to FBs, positive samples were detected using both methods, with 19 positive samples (60% of total) by ELISA and 14 positive samples (46.6% of total) by HPLC and levels ranging from 0.148 to 2.587 mg/kg. Correlation was observed between both methods (r = 0.516, p = 0.004) for FBs results. No sample exceeded the European maximum levels for any of the mycotoxins. Water activity of samples ranged from 0.345 to 0.655, suggesting that mycotoxin occurrence is probably related to raw material conta...

The physiological system of molluscs, particularly pro-oxidant and antioxidant mechanisms, could be altered by pollutants and induce disturbance on health status and productive parameters of aquatic organisms, such as oyster. Therefore, the aim of this study was to evaluate the chemical contamination in water (total metals and polycyclic aromatic hydrocarbons) and oxidative stress parameters in oysters (Crassostrea corteziensis) in Camichin estuary, located in Mexican Tropical Pacific. The results obtained showed the presence of arsenic, lead and zinc, as well as naphthalene, pyrene and benzo[a]pyrene in concentrations relatively higher than criteria established by local and international guidelines. Regarding the biomarkers of oxidative stress response (H2O2 and O2 concentration, catalase activity, lipid peroxidation, and hydroperoxide concentration), differences between oyster from estuary and control group were significant. These results indicate that these pollutants could be related with oxidative stress detected in oyster.

Aflatoxins represent, among all known mycotoxins, the best characterised and most investigated foodborne contaminants at present. This importance led to early research on acute and chronic toxicity. Further research showed that chronic toxicity due to aflatoxins could cause silent damages, causing the more evident carcinomas, being immunotoxicity one of the first toxicological effects studied on both mammals and aquatic farmed species, such as fishes. Although many of the aflatoxin immunotoxicity scientific information has been generated a quarter of century ago, the recent role of innate immune system on aquatic species still demands for up-to-date results, and expresses that the research on immunotoxicity caused by aflatoxins is yet to be completed. Based on these considerations, the aims of this review are to collect existing data on toxic effects on immune response of teleost fishes due to aflatoxins that could give us a perspective for the follow up research, and to gain new insights on the importance caused by the consumption of aflatoxin contaminated fish through the trophic chain.

Fish rearing under intensive farming conditions can be easily disturbed by pesticides, substances that have immunotoxic properties and may predispose to infections. Organophosphorus pesticides (OPs) are widely used in agricultural activities; however, the mechanism of immunotoxicity of these substances is unclear. The aim of this study was to evaluate the effect of diazinon pesticides (OPs) on the cholinergic system of immune cells as a possible target of OP immunotoxicity. We evaluated ACh levels and cholinergic (nicotinic and muscarinic) receptor concentration. Additionally, AChE activity was evaluated in mononuclear cells of Nile tilapia (Oreochromis niloticus), a freshwater fish mostly cultivated in tropical regions around the world. The obtained results indicate that acute exposure to diazinon induces an increase in ACh concentration and a decrease in nAChR and mAChR concentrations and AChE activity in fish immune cells, This suggests that the non-neuronal lymphocytic cholinergic system may be the main target in the mechanism of OP immunotoxicity. This study contributes to the understanding of the mechanisms of immunotoxicity of pollutants and may help to take actions for animal health improvement.

Immune response is modulated by different substances that are present in the environment. Nevertheless, some of these may cause an immunotoxic effect. In this paper, the effect of organophosphorus pesticides (frequent substances spilled in aquatic ecosystems) on the immune system of fishes and in immunotoxicology is reviewed. Furthermore, some cellular and molecular mechanisms that might be involved in immunoregulation mechanisms of organophosphorus pesticides are discussed.

Chlorpyrifos is an organophosphorous insecticide widely used in agriculture and domestic activities. However, little is known about the effect of this pesticide on the immune system of fish and other alterations of its physiological system. The aims of the present study were the evaluation of the LC(50) (lethal concentration(50)) and the potential toxicity of this substance on Nile tilapia (Oreochromis nilotucus), as well as its effect on some hematological values and phagocytic functions of this fish. Results obtained showed that chlorpyrifos does not have any effect on the following parameters: number of red blood cells, hemoglobin, hematocrit, mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), and mean corpuscular hemoglobin concentration (MCHC). However, the phagocytic index and the percentage of phagocytic active cells were significantly affected, which could indicate that phagocytic parameters from Nile tilapia are more sensitive than hematological ones to assess the effect of acute intoxication with chlorpyrifos.

Fish resistance to microorganisms depends basically on the immune response. Although there are several studies on the diazinon mammalian immunotoxicity, in the case of fish there are only few. The aim of present study was to evaluate the effect of diazinon on immunological parameters (relative spleen weight, splenocytes count, lysozyme activity, respiratory burst and IgM concentration) in Nile tilapia. Diazinon at sublethal concentrations (0.39 and 0.78 mg/L) did not alter RSW, splenocytes count or lysozyme activity. However, at the highest concentration tested (1.96 mg/L) diazinon significantly increased respiratory burst and IgM concentration. In summary, diazinon (and perhaps other pesticides) could alter immunological response and induce oxidative stress.