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.
•Diazinon diminishes phagocytic capacity of Nile tilapia leukocytes.•Diazinon increases reactive oxygen species production of Nile tilapia leukocytes.•Phagocytosis and ROS production can be use as effect biomarkers on OPs exposure.
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.
The polymerization of aniline hydrochloride by inverse microemulsion in a batch process and the semicontinuous process was studied as a function of the surfactant ionic and nonionic. Polymerizations ...were carried out at 60°C for 4 h with a yield polymer of circa 67 and 27% wt. for ionic and nonionic surfactants. The conductivity of synthesized polyaniline by the semicontinuous process is higher up to three orders of magnitude than that of the batch process for both surfactants. The calculating degree of oxidation by UV-Vis showed the relative intensities of the quinoid to benzenoid unit around one. The morphology was determined by Scanning Electron Microscopy (SEM) and observed that the formation of the different morphologies is due to the self-assembly behavior of surfactant. The diameter z-average particle size (Dz) was studied by Transmission Electron Microscopy (TEM), which determined that the diameter particle in a semicontinuous state is larger than the one produced in a batch; this is due to the control of monomer addition in the system. These findings suggest that the polymerization process and the type of surfactant influence the properties of polyaniline.
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Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Summary
The paper focuses on the identification of atypical fractures (AFFs). This paper examines the concordance between objective classification and expert subjective review. We believe the paper ...adds critical information about how to apply the American Society of Bone and Mineral Research (ASBMR) criteria to diagnose AFFs and is of high interest to the field.
Introduction
Assess American Society of Bone and Mineral Research (ASBMR) criteria for identifying atypical femoral fractures (AFFs).
Methods
Two orthopedic surgeons independently evaluated radiographs of 372 fractures, applying ASBMR criteria. We assessed ease of applying ASBMR criteria and whether criteria-based assessment matched qualitative expert assessment.
Results
There was up to 27% uncertainty about how to classify specific features. 84% of films were classified similarly for the presence of AFF according to ASBMR criteria; agreement increased to 94% after consensus meeting. Of 37 fractures categorized as AFFs based on ASBMR criteria, 23 (62.2%) were considered AFFs according to expert assessment (not relying on criteria). Only one (0.5%) femoral shaft fracture that did not meet ASBMR criteria was considered an AFF per expert assessment. The number of major ASBMR features present (four vs five) and whether there was periosteal or endosteal thickening (“beaking” or “flaring”) played major roles in the discrepancies between ASBMR criteria-based and expert-based determinations.
Conclusions
ASBMR AFF criteria were useful for reviewers but several features were difficult to interpret. Expert assessments did not agree with the ASBMR classification in almost one-third of cases, but rarely identified an AFF when a femoral shaft fracture did not meet ASBMR AFF criteria. Experts identified lateral cortical transverse fracture line and associated new-bone formation along with no or minimal comminution as crucial features necessary for the definition of atypical femoral fractures.
We sought to determine if echocardiography enhances prediction of first age-related cardiovascular events.
Whether echocardiographic assessment improves risk stratification for first cardiovascular ...events is not well known.
This retrospective cohort study included randomly selected residents of Olmsted County, Minnesota, age ≥65 years, who had ≥1 transthoracic echocardiograms at the Mayo Clinic between 1990 and 1998, in sinus rhythm, without valvular or congenital heart disease, and followed through medical records for first myocardial infarction (MI), coronary revascularization, atrial fibrillation (AF), congestive heart failure (CHF), transient ischemic attack (TIA), stroke, or cardiovascular death. Patients were excluded if they had any of these events before the baseline echocardiogram.
Of 1,160 patients (age 75 ± 7 years; 746 women) followed for a mean of 3.8 ± 2.7 years, 333 (29%) first events occurred (70 AF, 67 coronary revascularization procedures, 65 CHF, 48 MI, 38 stroke, 25 TIA, and 20 cardiovascular deaths). In a multivariate model, age (p < 0.001), male gender (p < 0.001), diabetes mellitus (p = 0.005), systemic hypertension (p < 0.001), left atrial volume/body surface area ≥32 ml/m2(p = 0.003), left ventricular (LV) mass/height ≥120 g/m (p = 0.014), LV systolic dysfunction (p < 0.001), and LV diastolic dysfunction (p = 0.029) were independent predictors. A risk-scoring algorithm was developed and validated for the prediction of first events. The five-year event-free survival was 90%, 74%, and 50% for low-, medium-, and high-risk groups, respectively.
Echocardiography enhanced prediction of first cardiovascular events in this referral-based elderly cohort. Its role in risk stratification for primary prevention of these events in the community warrants further investigations.
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.
•DZN provokes alteration in intracytoplasmatic signals.•DZN increases the flow of intracellular Ca2+ and ERK1/2 phosphorylation in leukocytes of Nile tilapia.•DZN causes loss of ΔΨm and induces senescence and apoptosis in fish leukocytes.
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.
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•OPs are capable of disrupting the cholinergic system of SMNC in Nile tilapia.•AChE activity is inhibited in SMNC exposed in-vitro to 1 and 10 μM of DXN.•DXN alters the expression of mAChR and nAChR in SMNC of Nile tilapia.•DXN inhibits AChE but also alters " non-conventional " targets such as AChR.
Country-specific soil organic carbon (SOC) estimates are the baseline for
the Global SOC Map of the Global Soil Partnership (GSOCmap-GSP). This
endeavor is key to explaining the uncertainty of global ...SOC estimates but
requires harmonizing heterogeneous datasets and building country-specific
capacities for digital soil mapping (DSM). We identified country-specific
predictors for SOC and tested the performance of five predictive algorithms
for mapping SOC across Latin America. The algorithms included support vector
machines (SVMs), random forest (RF), kernel-weighted nearest neighbors (KK),
partial least squares regression (PL), and regression kriging based on
stepwise multiple linear models (RK). Country-specific training data and SOC
predictors (5 × 5 km pixel resolution) were obtained from
ISRIC – World Soil Information. Temperature, soil type, vegetation
indices, and topographic constraints were the best predictors for SOC, but
country-specific predictors and their respective weights varied across Latin
America. We compared a large diversity of country-specific datasets and
models, and were able to explain SOC variability in a range between ∼ 1 and ∼ 60 %, with no universal predictive algorithm among
countries. A regional (n = 11 268 SOC estimates) ensemble of these
five algorithms was able to explain ∼ 39 % of SOC variability from
repeated 5-fold cross-validation. We report a combined SOC stock of
77.8 ± 43.6 Pg (uncertainty represented by the full conditional
response of independent model residuals) across Latin America. SOC stocks
were higher in tropical forests (30 ± 16.5 Pg) and croplands
(13 ± 8.1 Pg). Country-specific and regional ensembles revealed
spatial discrepancies across geopolitical borders, higher elevations, and
coastal plains, but provided similar regional stocks (77.8 ± 42.2 and
76.8 ± 45.1 Pg, respectively). These results are conservative
compared to global estimates (e.g., SoilGrids250m 185.8 Pg, the Harmonized
World Soil Database 138.4 Pg, or the GSOCmap-GSP 99.7 Pg). Countries with
large area (i.e., Brazil, Bolivia, Mexico, Peru) and large spatial SOC
heterogeneity had lower SOC stocks per unit area and larger uncertainty in
their predictions. We highlight that expert opinion is needed to set boundary
prediction limits to avoid unrealistically high modeling estimates. For
maximizing explained variance while minimizing prediction bias, the selection
of predictive algorithms for SOC mapping should consider density of available
data and variability of country-specific environmental gradients. This study
highlights the large degree of spatial uncertainty in SOC estimates across
Latin America. We provide a framework for improving country-specific mapping
efforts and reducing current discrepancy of global, regional, and
country-specific SOC estimates.
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.
•DZO causes disturbances in intracellular Ca2+ flow in fish mononuclear cells.•DZO inhibits ERK1/2 phosphorylation in fish mononuclear cells.•DZO induces apoptosis, senescence, and loss of ΔΨm in fish mononuclear cells.
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.
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•Cholinergic receptors are present on fish leukocytes.•Brain and spleen mononuclear cells express the muscarinic acetylcholine receptor subtypes M2, M3, M4, and M5A.•The mRNA levels of all the evaluated mAChR subtypes were higher on spleen mononuclear cells than the brain.
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