Antimicrobials in Eisenia fetida earthworms: A comprehensive study from method development to the assessment of uptake and degradation

In this work, an accurate analytical method was developed for the simultaneous analysis of twenty-seven antimicrobials (AMs) in earthworms using liquid chromatography coupled to a triple quadrupole mass spectrometry detector (UHPLC-MS/MS). Adequate apparent recoveries (80-120 %) and limits of quantification (LOQ) (1 μg·kg-1 - 10 μg·kg-1) were obtained, with the exception of norfloxacin (34 μg·kg-1). The method was applied to evaluate the accumulation of sulfamethazine (SMZ) and tetracycline (TC) in earthworms after performing OECD-207 toxicity test, in which Eisenia fetida (E. fetida) organisms were exposed to soils spiked with 10 mg·kg-1, 100 mg·kg-1 or 1000 mg·kg-1 of SMZ and TC, individually. The results confirmed the bioaccumulation of both AMs in the organisms, showing a greater tendency to accumulate SMZ since higher bioconcentration factor values were obtained for this compound at the exposure concentrations tested. In addition, the degradation of both AMs in both matrices, soils and earthworms was studied using liquid chromatography coupled to a q-Orbitrap high resolution mass spectrometry detector. Thirteen transformation products (TPs) were successfully identified, eight of them being identified for the first time in soil/earthworm (such as 4-Amino-3-chloro-n-(4,6-dimethylpyrimidin-2-yl)benzenesulfonamide or 4-(dimethylamino)-1,11,12a-trihydroxy-6,6-dimethyl-3,7,10,12-tetraoxo-3,4,4a,5,5a,6,7,10,12,12a-decahydrotetracene-2-carboxamide, among others) and their formation/degradation trend over time was also studied. Regarding the biological effects, only SMZ caused changes in earthworm growth, evidenced by weight loss in earthworms exposed to concentrations of 100 mg·kg-1 and 1000 mg·kg-1. Riboflavin decreased at all concentrations of SMZ, as well as at the highest concentration of TC. This indicates that these antibiotics can potentially alter the immune system of E. fetida. This research represents a significant advance in improving our knowledge about the contamination of soil by AM over time. It investigates the various ways in which earthworms are exposed to AMs, either by skin contact or ingestion. Furthermore, it explores how these substances accumulate in earthworms, the processes by which earthworms break them down or metabolise them, as well as the resulting TPs. Finally, it examines the potential effects of these substances on the environment.

Life after death? Exploring biochemical and molecular changes following organismal death in green turtles, Chelonia mydas (Linnaeus, 1758)

Green turtles, Chelonia mydas, have been included in biomonitoring efforts given its status as an endangered species. Many studies, however, rely on samples from stranded animals, raising the question of how death affects important biochemical and molecular biomarkers. The goal of this study was to investigate post mortem fluctuations in the antioxidant response and metabolism of carbohydrates in the liver of C. mydas. Liver samples were obtained from six green turtles which were submitted to rehabilitation and euthanized due to the impossibility of recovery. Samples were collected immediately after death (t = 0) and at various time intervals (1, 2, 3, 4, 5, 6, 12, 18 and 24 h post mortem), frozen in liquid nitrogen and stored at -80 °C. The activities of catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR) and glucose-6-phosphate dehydrogenase (G6PDH) were analyzed, as were the levels of lipid peroxidation, glycogen concentration, RNA integrity (RNA IQ) and transcript levels of carbonic anhydrase and pyruvate carboxylase genes. Comparison between post mortem intervals showed a temporal stability for all the biomarkers evaluated, suggesting that changes in biochemical and molecular parameters following green turtle death are not immediate, and metabolism may remain somewhat unaltered up to 24 h after death. Such stability may be associated with the overall lower metabolism of turtles, especially under an oxygen deprivation scenario such as organismal death. Overall, this study supports the use of biomarkers in sea turtles sampled within a period of 24 h post mortem for biomonitoring purposes, though it is recommended that post mortem fluctuations of particular biomarkers be evaluated prior to their application, given that proteins may show varying degrees of susceptibility to proteolysis.

SAFIIRA: A heavy-ion multi-purpose irradiation facility in Brazil

This work describes the new facility for applied nuclear physics at the University of Sao Paulo, mainly for irradiation of electronic devices. It is a setup composed of a quadrupole doublet for beam focusing/defocusing plus multiple scattering through gold foils to produce low intensity, large-area, and high-uniformity heavy-ion beams from ¹H to ¹⁰⁷Ag. Beam intensities can be easily adjusted from 10² particles cm²/s to hundreds of nA for an area as large as 2.0 cm² and uniformity better than 90%. Its irradiation chamber has a high-precision motorized stage, and the system is controlled by a LabView^TM environment, allowing measurement automation. Design considerations and examples of use are presented.

Neurotoxicity in zebrafish exposed to carbon nanotubes: Effects on neurotransmitters levels and antioxidant system

Given the increasing use of carbon nanotubes (CNT) in several industries and technological applications, it is essential to perform in vivo toxicological studies with these nanomaterials to evaluate their potential ecotoxicity. Dopamine (DA) and serotonin (5HT) are key neurotransmitters for brain functions and behavioral responses. Determination of DA and 5HT were performed in brain samples from zebrafish Danio rerio exposed i.p. to single-walled CNT (SWCNT), besides analyzing acetylcholinesterase (AChE) and ectonucleotidases activity, lipid peroxidation and total antioxidant capacity. Results showed that treatment with SWCNT increased between 3 and 6-fold the concentration of DA and 5HT (p < 0.05). Similarly, a significant reduction (p < 0.05) in AChE activity was observed in the brains of SWCNT exposed zebrafish when compared to the control groups. Cholinergic, serotonergic, and dopaminergic systems, through AChE activity and serotonin and dopamine levels, respectively were affected by SWCNT in the zebrafish brain. Alterations in these neurotransmitters can potentially affect several physiological and behavioral that they control.

Molecular analysis of clonally related Salmonella Typhi recovered from epidemiologically unrelated cases of typhoid fever, Brazil

BACKGROUND

The primary method of molecular subtyping for the identification and investigation of outbreaks has been pulsed-field gel electrophoresis (PFGE). In some cases, this technique has not been able to show discrimination between the unrelated strains that can be achieved by whole genome sequencing (WGS).

METHODS

The aim of this study was to determine the strengths and drawbacks of WGS using different analytic approaches compared to traditional typing method, PFGE, for retrospectively typing clusters cases of 28 S. Typhi.

RESULTS

We evaluated three analytical approaches on the WGS data set (Nucleotide Difference (ND), (SNPs) and Whole genome multi locus sequence typing (wgMLST) that identically classified the clusters-related strains into two clusters, cluster A (with strains from 2017), and Cluster B (with strains from 2007).

CONCLUSIONS

In this study WGS based typing, was able to compete with PFGE for differentiation of the clusters of S. Typhi strains.

Poultry rearing on perforated plastic floors and the effect on air quality, growth performance, and carcass injuries - Experiment 2: Heat stress situation

Previously, we reported the effect of rearing conditions (plastic floors and air quality) on carcass injury development of broiler chickens at thermal comfort. In this study, the same rearing conditions were tested at thermal stress. The birds were reared in 2 climatic chambers, and the experiment followed a completely randomized design with one factor, flooring material: wood shaving or perforated plastic. The birds were divided into 16 experimental pens, being 8 females and 8 males. The studied parameters were the same as the previous study (ammonia concentration, carbon dioxide, performance, carcass yield, and variability, and scores of hygiene, gait and chest, and hocks and footpad lesions). Higher ammonia (15 ppm vs. 4 ppm) and carbon dioxide (1,000 ppm vs. 850 ppm) concentration was seen at d 42 for the wood shavings floor as compared to the perforated plastic floor, respectively. Regarding gender, males had better performance than females at 42 d of age on both floor types. Males reared on wood shavings showed a higher meat production (29.049 kg/m2) than females (24.700 kg/m2). There were observed breast lesion incidences of 10.4% (score 1) in males reared on the plastic floor, as well higher incidence of hock injury and footpad dermatitis. Chickens reared on plastic flooring showed better hygiene than chickens reared on wood shavings. Our findings revealed that the use of perforated plastic flooring in a heat stress situation can improve the air quality (less CO2 and NH3 concentration) and bird cleanliness. On the other hand, chickens are more susceptible to develop lesions in the breast, hock, and footpad. We conclude that the use of plastic flooring in heat stress conditions needs more attention, since chickens are more susceptible to develop lesions on the carcass, being a source of pain, impairing bird wellbeing and causing losses in meat production.

Effects of malathion and cadmium on acetylcholinesterase activity and metallothionein levels in the fish Seriola dumerilli

The potential use of acetylcholinesterase (AChE) and metallothionein (MT) responses as biomarker of organophosphorous (OPs) and trace metal were assessed in fish Seriola dumerilli exposed to 0, 4, 6 mg/kg of malathion for 2, 7 and 13 days, and to 0, 50, 100, 250 mug/kg of Cd for 2 days. Brain AChE was significantly inhibited after 2 and 7 days of malathion exposure, in a dose-response manner, but no inhibition was observed after 13 days of exposure. When exposed to Cd for 2 days, S. dumerelli presented an increase in AChE activity at a concentration of 50 mug/kg, but a strong and dose-dependent AChE inhibition at 100 and 250 mug/kg. Cd treatment also caused a rapid increase in MTs concentration in liver, even at the lower concentration. Our experiments indicate that the measurement of hepatic MT concentration and brain AChE activity in S. dumerilli would be useful biomarkers of OP and Cd exposure and/or effects.

Focal adhesion kinase and p130Cas mediate both sarcomeric organization and activation of genes associated with cardiac myocyte hypertrophy

Hypertrophic terminally differentiated cardiac myocytes show increased sarcomeric organization and altered gene expression. Previously, we established a role for the nonreceptor tyrosine kinase Src in signaling cardiac myocyte hypertrophy. Here we report evidence that p130Cas (Cas) and focal adhesion kinase (FAK) regulate this process. In neonatal cardiac myocytes, tyrosine phosphorylation of Cas and FAK increased upon endothelin (ET) stimulation. FAK, Cas, and paxillin were localized in sarcomeric Z-lines, suggesting that the Z-line is an important signaling locus in these cells. Cas, alone or in cooperation with Src, modulated basal and ET-stimulated atrial natriuretic peptide (ANP) gene promoter activity, a marker of cardiac hypertrophy. Expression of the C-terminal focal adhesion-targeting domain of FAK interfered with localization of endogenous FAK to Z-lines. Expression of the Cas-binding proline-rich region 1 of FAK hindered association of Cas with FAK and impaired the structural stability of sarcomeres. Collectively, these results suggest that interaction of Cas with FAK, together with their localization to Z-lines, is critical to assembly of sarcomeric units in cardiac myocytes in culture. Moreover, expression of the focal adhesion-targeting and/or the Cas-binding proline-rich regions of FAK inhibited ANP promoter activity and suppressed ET-induced ANP and brain natriuretic peptide gene expression. In summary, assembly of signaling complexes that include the focal adhesion proteins Cas, FAK, and paxillin at Z-lines in the cardiac myocyte may regulate, either directly or indirectly, both cytoskeletal organization and gene expression associated with cardiac myocyte hypertrophy.

Plasma membrane-associated pY397FAK is a marker of cytotrophoblast invasion in vivo and in vitro

During human pregnancy specialized placental cells of fetal origin, termed cytotrophoblasts, invade the uterus and its blood vessels. This tumor-like process anchors the conceptus to the mother and diverts the flow of uterine blood to the placenta. Previously, we showed that the expression of molecules with important functional roles, including a number of extracellular matrix integrin receptors, is precisely modulated during cytotrophoblast invasion in situ. Here we exploited this observation to study the role of the focal adhesion kinase (FAK), which transduces signals from the extracellular matrix and recruits additional signaling proteins to focal adhesions. Immunolocalization studies on tissue sections showed that FAK is expressed by cytotrophoblasts in all stages of differentiation. Because extracellular matrix-induced integrin clustering results in FAK (auto)phosphorylation on tyrosine 397 (Y397FAK), we also localized this form of the molecule. Immunolocalization experiments detected Y397FAK in a subset of cytotrophoblasts near the surface of the uterine wall. To assess the functional relevance of this observation, we used an adenovirus strategy to inhibit cytotrophoblast expression of FAK as the cells differentiated along the invasive pathway in vitro. Compared to control cells transduced with a wild-type virus, cytotrophoblasts that expressed antisense FAK exhibited a striking reduction in their ability to invade an extracellular matrix substrate. When cytotrophoblast differentiation was compromised (hypoxia in vitro, preeclampsia in vivo), Y397FAK levels associated with the plasma membrane were strikingly lower, although total FAK levels did not change. Together our results suggest that (auto)phosphorylation of Y397 on FAK is a critical component of the signaling pathway that mediates cytotrophoblast migration/invasion.

Chagasic megaesophagus and megacolon diagnosed in childhood and probably caused by vertical transmission

Reports on children presenting symptoms compatible with the chronic phase of Chagas disease are sporadic. We report a case of a 7-year-old boy who had megaesophagus and megacolon, both of them a consequence of the trypanosomiasis. The etiology was established by means of laboratory and histological features. Based on epidemiological data, the authors concluded that vertical transmission was the most probable route of acquisition. This diagnosis should be considered in children presenting similar complaints, even those living away from endemic areas.

Biochemical responses in farmed mussel Perna perna transplanted to contaminated sites on Santa Catarina Island, SC, Brazil

The effects of contaminants on the biochemical parameters of the intensively farmed mussel Perna perna, are unknown. The aim of this study was to compare biochemical responses in mussels held in clean and contaminated sites in Santa Catarina Island, Brazil. Mussels were transplanted from a farming area, Ratones Grande Island (RGI), to two contaminated sites, Itacorubi (ITAC) and Hercílio Luz Bridge (HLB). A reference group was kept at RGI. After 150 and 180 days of exposure, the digestive glands of the mussels were analyzed for catalase, glucose 6-phosphate dehydrogenase (G6PDH) and glutathione S-transferase (GST) activities. No changes were observed in the catalase activity, in both periods. Low G6PDH activity was observed in mussels transplanted for 150 days at the ITAC site. Increased GST activity was observed in mussels from ITAC and HLG sites after 180 days. These responses are probably related to the augmented discharges of domestic effluents associated with elevated rainfall index.

Sequence-specific interaction between the disintegrin domain of mouse ADAM 2 (fertilin beta) and murine eggs. Role of the alpha(6) integrin subunit

Little is yet known about the biological and biochemical properties of the disintegrin-like domains of ADAM (a disintegrin and metalloprotease) proteins. Mouse ADAM 2 (mADAM 2; fertilin beta) is a sperm surface protein involved in murine fertilization. We produced recombinant proteins containing the disintegrin-like domain of mADAM 2 in both insect cells and in bacteria. The protein produced in insect cells (baculo D+C) contained a signal sequence followed by the disintegrin-like and cysteine-rich domains; it was purified from the medium of recombinant baculovirus-infected cells. A bacterial construct containing the disintegrin-like domain was produced in Escherichia coli as a glutathione S-transferase chimera. Baculo D+C, as well as the D domain of the bacterial construct (released with thrombin), bound to the microvillar surface of murine eggs. Using concentrations in the range of 1 to 5 microM, both recombinant proteins strongly inhibited sperm-egg binding and fusion; the baculovirus-produced protein exhibited a somewhat greater extent of inhibition (approximately 75 versus approximately 55% maximal inhibition). Substitution of alanine for each of the five charged residues within the disintegrin loop of mADAM 2 revealed a critical importance for the aspartic acid at position nine. Binding of both recombinant proteins to the egg was inhibited by the function blocking anti-alpha(6) monoclonal antibody, GoH3, but not by a nonfunction-blocking anti-alpha(6) monoclonal antibody. Binding was also inhibited by a peptide analogue of, and with an antibody against, the disintegrin loop of mADAM 2.

Evidence that distinct states of the integrin alpha6beta1 interact with laminin and an ADAM

Integrins can exist in different functional states with low or high binding capacity for particular ligands. We previously provided evidence that the integrin alpha6beta1, on mouse eggs and on alpha6-transfected cells, interacted with the disintegrin domain of the sperm surface protein ADAM 2 (fertilin beta). In the present study we tested the hypothesis that different states of alpha6beta1 interact with fertilin and laminin, an extracellular matrix ligand for alpha6beta1. Using alpha6-transfected cells we found that treatments (e.g., with phorbol myristate acetate or MnCl2) that increased adhesion to laminin inhibited sperm binding. Conversely, treatments that inhibited laminin adhesion increased sperm binding. Next, we compared the ability of fluorescent beads coated with either fertilin beta or with the laminin E8 fragment to bind to eggs. In Ca2+-containing media, fertilin beta beads bound to eggs via an interaction mediated by the disintegrin loop of fertilin beta and by the alpha6 integrin subunit. In Ca2+-containing media, laminin E8 beads did not bind to eggs. Treatment of eggs with phorbol myristate acetate or with the actin disrupting agent, latrunculin A, inhibited fertilin bead binding, but did not induce laminin E8 bead binding. Treatment of eggs with Mn2+ dramatically increased laminin E8 bead binding, and inhibited fertilin bead binding. Our results provide the first evidence that different states of an integrin (alpha6beta1) can interact with an extracellular matrix ligand (laminin) or a membrane-anchored cell surface ligand (ADAM 2).

Extracellular matrix survival signals transduced by focal adhesion kinase suppress p53-mediated apoptosis

In many malignant cells, both the anchorage requirement for survival and the function of the p53 tumor suppressor gene are subverted. These effects are consistent with the hypothesis that survival signals from extracellular matrix (ECM) suppress a p53-regulated cell death pathway. We report that survival signals from fibronectin are transduced by the focal adhesion kinase (FAK). If FAK or the correct ECM is absent, cells enter apoptosis through a p53-dependent pathway activated by protein kinase C lambda/iota and cytosolic phospholipase A2. This pathway is suppressible by dominant-negative p53 and Bcl2 but not CrmA. Upon inactivation of p53, cells survive even if they lack matrix signals or FAK. This is the first report that p53 monitors survival signals from ECM/FAK in anchorage- dependent cells.

ADAMs and cell fusion

Members of the ADAM family (membrane proteins with a disintegrin and metalloprotease domain) have been implicated in several cell-interactive events, including cell-cell fusion. Recent evidence implicates three ADAMs, fertilin-alpha, fertilin-beta, and meltrin-alpha, in sperm-egg fusion and myoblast fusion. In light of the large number and wide tissue distribution of the ADAMs, they may also participate in other cell-cell fusion events. As ADAMs are also found in both vertebrates and invertebrates, some features of cell-cell fusion reactions may be conserved throughout the animal kingdom.

Cutaneous botryomycosis. Report of the two first Uruguayan cases

The first two Uruguayan cases of botryomycosis were diagnosed in white adult male patients with cutaneous lesions. Staphylococcus aureus was the etiologic agent in both cases. In one of them, however, Pseudomonas aeruginosa was also identified during relapse. General comments on diagnosis and pathogenesis of the disease are made.

Mouse egg integrin alpha 6 beta 1 functions as a sperm receptor

Binding between sperm and egg plasma membranes is an essential step in fertilization. Whereas fertilin, a mammalian sperm surface protein, is involved in this crucial interaction, sperm receptors on the egg plasma membrane have not been identified. Because fertilin contains a predicted integrin ligand domain, we investigated the expression and function of integrin subunits in unfertilized mouse eggs. Polymerase chain reactions detected mRNAs for alpha 5, alpha 6, alpha v, beta 1, beta 3, and beta 5. Immunofluorescence revealed alpha 6 beta 1 and alpha v beta 3 on the plasma membrane. GoH3, a function-blocking anti-alpha 6 monoclonal antibody, abolished sperm binding, but a nonfunction-blocking anti-alpha 6 monoclonal antibody, a function-blocking anti-alpha v beta 3 polyclonal antibody, and an RGD peptide had no effect. Somatic cells bound sperm avidly, but only if they expressed alpha 6 beta 1. A peptide analog of the fertilin integrin ligand domain inhibited sperm binding to eggs and alpha 6 beta 1+ cells and diminished GoH3 staining of eggs. Our results indicate a novel role for the integrin alpha 6 beta 1 as a cell-cell adhesion receptor that mediates sperm-egg binding.

Endothelial dysfunction in coronary vessels and thoracic aorta of rats exposed to cigarette smoke

1. The aim of this study was to evaluate the role of endothelium in mediating the response to acetylcholine in the thoracic aorta and coronary vessels of rats exposed to cigarette smoking. Total serum cholesterol was measured at the beginning and end of the experiment. 2. The relaxation response to acetylcholine was significantly impaired in the aortae of rats exposed to cigarette smoking (P < 0.05); and the coronary flow during the administration of acetylcholine (0.02 microgram/min.) was significantly reduced (P < 0.05). The total cholesterol plasma levels increased 31.13% in those exposed to smoke when compared to the controls (P < 0.05). 3. It is concluded that exposure to cigarette smoking increases total serum cholesterol levels, and also produces primary endothelial dysfunction in aorta rings and coronary vessels.

Leishmania braziliensis braziliensis infection of the nipple

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