Meat Juice and Oral Fluid as Alternatives to Serum for Aujeszky Disease Monitoring in Pigs.

Aujeszky Disease Virus (ADV) is a double-stranded DNA virus with a lipoprotein envelope. The natural hosts of the infection are Suidae, but the virus can infect many other mammals. The gold-standard method identified by the WOAH for the diagnosis of Aujeszky disease is the ELISA method. The objective of this study was to compare the performance of meat juice and oral fluid matrices using a commercial ELISA kit designed for serum. A total of 80 blood and oral fluid samples were collected from four pig farms selected for this study. Diaphragm muscle samples of about 100 g and blood samples were collected from 213 animals at the abattoir. These biological matrices were collected from the same animals and tested using a competitive ELISA kit to detect antibodies against ADV. The relative accuracy of the meat juice compared to that of the serum was 96.7% (95% CI: 93.3-98.7%), with 206 correct results out of 213. The relative accuracy of the oral fluid compared to that of the serum was 61.3% (95% CI: 49.7-71.9%), with 58 correct results out of 80. Meat juice has a better combination of sensitivity and specificity than oral fluid. The usage of meat juice in routine diagnostic examinations could be achieved after further investigations to optimize the procedure.

A Qualitative PCR Assay for the Discrimination of Bubaline Herpesvirus 1, Bovine Herpesvirus 1 and Bovine Herpesvirus 5.

Bubaline herpesvirus 1 (BuHV-1), Bovine herpesvirus 1 (BoHV-1) and Bovine herpesvirus 5 (BoHV-5) are classified in the genus Varicellovirus, subfamily Alphaherpesvirinae. BoHV-1 is the causative agent of infectious bovine rhinotracheitis, BoHV-5 induces moderate disease in adult cattle while BuHV-1 has instead been associated with a decline in livestock production of water buffaloes. The aim of this study was to develop a qualitative PCR assay that allows the discrimination of BuHV-1, BoHV-1 and BoHV-5. The alignment of homologous genes identified specific nucleotide sequences of BuHV- 1, BoHV-1 and BoHV-5. The design of the primers and the optimization of the PCR assay were focused on the target sequences located on the portions of gD, gE and gG genes. This assay involved the use of three different PCR end-points: the PCR of a portion of the gD gene identified only the presence of BoHV-1; the PCR of a portion of the gE gene confirmed the presence of both BoHV-5 and BuHV-1; the PCR of a portion of the gG gene discriminated between BoHV-5 and BuHV-1, as the amplification product was observed only for BoHV-5. This qualitative PCR assay allowed the differentiation of BoHV-1 and BoHV-5 infections both in cattle and water buffaloes and heterologous BuHV-1 infections in bovine.

Molecular Characterization of the First African Swine Fever Virus Genotype II Strains Identified from Mainland Italy, 2022.

African swine fever (ASF) is responsible for important socio-economic effects in the global pig industry, especially for countries with large-scale piggery sectors. In January 2022, the African swine fever virus (ASFV) genotype II was identified in a wild boar population in mainland Italy (Piedmont region). This study describes the molecular characterization, by Sanger and next-generation sequencing (NGS), of the first index case 632/AL/2022 and of another isolate (2802/AL/2022) reported in the same month, in close proximity to the first, following multiple ASF outbreaks. Phylogenetic analysis based on the B646L gene and NGS clustered the isolates 632/AL/2022 and 2802/AL/2022 within the wide and most homogeneous p72 genotype II that includes viruses from European and Asian countries. The consensus sequence obtained from the ASFV 2802/AL/2022 isolate was 190,598 nucleotides in length and had a mean GC content of 38.38%. At the whole-genome level, ASF isolate 2802/AL/2022 showed a close genetic correlation with the other representative ASFV genotype II strains isolated between April 2007 and January 2022 from wild and domestic pigs in Eastern/Central European (EU) and Asian countries. CVR subtyping clustered the two Italian ASFV strains within the major CVR variant circulating since the first virus introduction in Georgia in 2007. Intergenic region I73R-I329L subtyping placed the Italian ASFV isolates within the variant identical to the strains frequently identified among wild boars and domestic pigs. Presently, given the high sequence similarity, it is impossible to trace the precise geographic origin of the virus at a country level. Moreover, the full-length sequences available in the NCBI are not completely representative of all affected territories.

First Report of Swinepox in a Wild Boar in Italy: Pathologic and Molecular Findings.

Swinepox virus (SWPV) is responsible for sporadic acute poxvirus infections in swine worldwide, causing a pathognomonic eruptive proliferative dermatitis. Beside direct and congenital transmission, the pig louse Haematopinus suis acts as a mechanical vector and favors virus infection through skin lesions. Infections are generally described in domestic pigs, while only a few cases have been reported in wild boars, in Austria and Germany. In September 2022, SWPV infection was suspected at post-mortem examination of a wild boar piglet with characteristic lesions in Liguria, Northwest Italy. The piglet was heavily parasitized by swine lice (H. suis). SWPV was then confirmed by histological and molecular analyses. Possible viral co-infections were also investigated (African swine fever virus, classical swine fever virus, parvovirus, circovirus, Aujeszky's disease virus and hepatitis E virus). This article describes gross and histopathologic features of SWPV infection, differential diagnosis, and potential vector-borne transmission to domestic pigs, presenting a brief review of the literature on the topic. SWPV infection is reported in wild boars in Italy for the first time. The finding of SWPV in a wild boar in an area with a very limited pig population may suggest the existence of a "wildlife cycle" in the area. Further investigations are needed to understand the real risk of transmission of SWPV to domestic pigs as well as the role of other arthropod vectors.

Pro-Inflammatory and Cytotoxic Effects of Polystyrene Microplastics on Human and Murine Intestinal Cell Lines.

Plastic is a polymer extremely resistant to degradation that can remain for up to hundreds or thousands of years, leading to the accumulation of massive amounts of plastic waste throughout the planet's ecosystems. Due to exposure to various environmental factors, plastic breaks down into smaller particles named microplastics (1-5000 µm) and nanoplastics (<1 µm). Microplastics (MPs) are ubiquitous pollutants but, still, little is known about their effects on human and animal health. Herein, our aim is to investigate cytotoxicity, oxidative stress, inflammation and correlated gene modulation following exposure to polystyrene microplastics (PS-MPs) in HRT-18 and CMT-93 epithelial cell lines. After 6, 24 and 48 h PS-MPs treatment, cell viability (MTT) and oxidative stress (SOD) assays were performed; subsequently, expression changes and cytokines release were investigated by Real-Time PCR and Magnetic-beads panel Multiplex Assay, respectively. For each exposure time, a significantly increased cytotoxicity was observed in both cell lines, whereas SOD activity increased only in CMT-93 cells. Furthermore, Magnetic-beads Multiplex Assay revealed an increased release of IL-8 in HRT-18 cells' medium, also confirmed by gene expression analysis. Results obtained suggest the presence of a pro-inflammatory pattern induced by PS-MPs treatment that could be related to the observed increase in cytotoxicity.

Molecular and serological investigation of Hepatitis E virus in pigs slaughtered in Northwestern Italy.

BACKGROUND: Hepatitis E Virus (HEV) is recently considered an emerging public health concern. HEV genotypes 1 and 2 are widely distributed and pathogenic only for humans. In contrast, HEV, genotypes 3 and 4 are observed in swine, deer, wild boars and rabbits and can also be transmitted to humans. The presence of HEV in the liver, muscle, faeces, blood, and bile was detected by real-time RT-PCR in 156 pigs belonging to twenty different farms, ranging from 1 to 8 months of age. The phylogenetic analysis was performed on the viral strain present in the positive biological matrix, with the lowest Ct. HEV-IgG and HEV-IgM in the sera were analysed by two different ELISA kits. RESULTS: Twenty-one pigs, i.e., 13.46% of them (21/156, 95% CI: 8.53%-19.84%), tested positive for HEV in at least one biological matrix by real-time RT-PCR, while phylogenetic analysis revealed the presence of HEV subtypes 3f and 3c. Pig serums analysed by ELISA showed an overall prevalence of 26.92% (42/156, 95% CI: 20.14%-34.60%) for HEV-IgG, whereas the 28.95% (33/114, 95% CI: 20.84%-38.19%) of them tested negative resulted positive for the HEV-IgM. CONCLUSIONS: The faeces are the biological matrix with the highest probability of detecting HEV. The best concordance value (Kappa Kohen index) and the highest positive correlation (Phi index) were observed for the correlation between bile and liver, even when the number of positive liver samples was lower than the positive bile samples. This finding may suggest that a higher probability of HEV occurs in the bile, when the virus is present in the liver, during the stages of infection. Finally, the presence of HEV in muscle was observed in 11 pigs, usually used for the preparation of some dishes, typical of the Italian tradition, based on raw or undercooked meat. Therefore, their consumption is a possible source of infection for final consumer.

Multi-Level System to Assess Toxicity in Water Distribution Plants.

The toxicity of water samples from water distribution plants needs to be investigated further. Indeed, studies on the pro-oxidant effects driven by tap water are very limited. In this study, the water quality, pro-oxidant effects, and potential health risks driven by exposure to groundwater samples from two water plants (sites A and B) located in Northwestern Italy were investigated in a multi-level system. Physicochemical parameters and the absence of pathogens, cyanotoxins, and endocrine active substances indicated a good water quality for both sites. The 25 metals analyzed were found under the limit of quantification or compliant with the maximum limits set by national legislation. Water samples were concentrated by the solid-phase extraction system in order to assess the aquatic toxicity on Epithelioma papulosum cyprini (EPC) cell line. Levels of superoxide dismutase, catalase, glutathione peroxidase, glutathione S-transferase, and glutathione reductase were evaluated through the Integrated Biomarkers Response (IBRv2) index. EPC cell line was found a sensible model for assessing the antioxidant responses driven by both water concentrates. A similar antioxidant response was shown by plots and IBRv2 suggesting a muted risk for the two sampling sites.

RT-QuIC detection of pathological prion protein in subclinical goats following experimental oral transmission of L-type BSE.

OBJECTIVE: The spread of bovine spongiform encephalopathy (BSE) agent to small ruminants is still a major issue in the surveillance of transmissible spongiform encephalopathies (TSEs). L-type bovine spongiform encephalopathy (L-BSE) is an atypical form of BSE with an unknown zoonotic potential that is transmissible to cattle and small ruminants. Our current knowledge of bovine atypical prion strains in sheep and goat relies only on experimental transmission studies by intracranial inoculation. To assess oral susceptibility of goats to L-BSE, we orally inoculated five goats with cattle L-BSE brain homogenates and investigated pathogenic prion protein (PrPsc) distribution by an ultrasensitive in vitro conversion assay known as Real-Time Quaking Induced Conversion (RT-QuIC). RESULTS: Despite a prolonged observation period of 80 months, all these animals and the uninfected controls did not develop clinical signs referable to TSEs and tested negative by standard diagnostics. Otherwise, RT-QuIC analysis showed seeding activity in five out of five examined brain samples. PrPsc accumulation was also detected in spinal cord and lymphoreticular system. These results indicate that caprine species are susceptible to L-BSE by oral transmission and that ultrasensitive prion tests deserve consideration to improve the potential of current surveillance systems against otherwise undetectable forms of animal prion infections.

Beware of dogs! Domestic animals as a threat for wildlife conservation in Alpine protected areas.

Diseases are natural regulating factors of wildlife populations, but some pathogens may become an important threat in wildlife conservation, especially for endangered species. The presence of domestic animals may foster the spread of diseases in natural population, although their role in the dynamic of infections in wildlife is not clear. In this study, we investigated the presence and prevalence of a range of multi-host pathogens in wild species (red fox, Eurasian badger, beech marten, pine marten, stoat for a total of 89 carcasses analysed) and domestic animals (n = 52 shepherd and n = 25 companion dogs) living in a protected area of the Alps (the Gran Paradiso National Park) and discussed the role of domestic dogs as possible source of infection for wild species. Our results showed that domestic dogs are potential shedder of three important pathogens: Canine distemper virus, Toxoplasma sp. and Neospora caninum. In particular, shepherd dogs seem to represent a threat for wildlife as they are exposed to multiple pathogens because of free-roaming, scavenging lifestyles and close proximity to livestock. However, also companion dogs more subject to veterinary care may foster the spread of pathogens. Our results highlight the importance of regulating the access of domestic dogs to protected areas that aim at preserving biodiversity and enhancing the conservation of endangered species.

Feline morbillivirus in northwestern Italy: first detection of genotype 1-B.

OBJECTIVES: A novel morbillivirus was recently described in stray and domestic cats in Asia, the USA and Europe. Most cats infected with feline morbillivirus (FeMV) showed lower urinary tract or kidney disease. Although the association of FeMV infection and kidney diseases has been suggested, the virus pathogenicity remains unclear. The present study aimed to investigate the distribution of FeMV infection, as well as the relationship between FeMV infection and kidney diseases in cats from northwestern Italy. METHODS: A total of 153 urine samples (150 individuals and three pools) and 50 kidney samples were collected and included in the study; total RNA was extracted and a reverse transcription quantitative PCR (RT-qPCR) was performed in order to identify FeMV. Kidneys were also submitted to anatomopathological examination. Phylogenetic analysis and isolation attempts were carried out on positive samples. In FeMV-positive cats, urinalysis and blood analysis were performed. RESULTS: FeMV RNA was detected in 7.3% of urine samples and in 8% of kidney samples, both in healthy cats and in cats with clinical signs/post-mortem lesions compatible with kidney disease. At histopathological examination, tubulointerstitial nephritis (TIN) was shown in 3/4 positive kidney samples, but a clear relationship between FeMV and TIN was not observed. Isolation attempts were unsuccessful, although the urine sample of one castrated male cat hosted in a cattery showed a positive signal in RT-qPCR until the fourth cell passage. Phylogenetic analysis revealed that this FeMV strain belonged to genotype 1-B. In the same cattery, a second genotype 1-B variant was detected from a urine pool. Urinalysis showed proteinuria in three cats, while at blood analysis three cats presented altered creatinine levels. CONCLUSIONS AND RELEVANCE: Data reported suggest the presence of a FeMV sub-cluster distinct from the strain previously isolated in Italy, whose role in renal disorders remains uncertain.

Specific capture and whole-genome phylogeography of Dolphin morbillivirus.

Dolphin morbillivirus (DMV) is considered an emerging threat having caused several epidemics worldwide. Only few DMV genomes are publicly available. Here, we report the use of target enrichment directly from cetacean tissues to obtain novel DMV genome sequences, with sequence comparison and phylodynamic analysis. RNA from 15 tissue samples of cetaceans stranded along the Italian and French coasts (2008-2017) was purified and processed using custom probes (by bait hybridization) for target enrichment and sequenced on Illumina MiSeq. Data were mapped against the reference genome, and the novel sequences were aligned to the available genome sequences. The alignment was then used for phylogenetic and phylogeographic analysis using MrBayes and BEAST. We herein report that target enrichment by specific capture may be a successful strategy for whole-genome sequencing of DMV directly from field samples. By this strategy, 14 complete and one partially complete genomes were obtained, with reads mapping to the virus up to 98% and coverage up to 7800X. The phylogenetic tree well discriminated the Mediterranean and the NE-Atlantic strains, circulating in the Mediterranean Sea and causing two different epidemics (2008-2015 and 2014-2017, respectively), with a limited time overlap of the two strains, sharing a common ancestor approximately in 1998.

Seroprevalence of Canine Herpesvirus-1 in Breeding Dogs with or Without Vaccination in Northwest Italy.

Canine herpesvirus-1 (CHV-1) can cause abortion and foetal and neonatal deaths in the bitch. The reactivation of latent infections with asymptomatic virus shedding represents a mechanism, whereby the virus can persist in a dog population. The aim of this study was to investigate the seroprevalence of CHV-1 in a population of breeding dogs in Piedmont, Northern Italy, and to investigate the distribution of herpesvirus vaccination. The study was carried out in 370 animals that were housed in 33 breeding kennels. Antibodies against CHV-1 in serum samples were measured by means of serum neutralization. Vaccination had been performed in 21.2% of the kennels and 8.4% of the dogs. The overall seroprevalence of CHV-1 was 50.3%. In ten kennels (30.3%), no seropositive dogs were identified. The percentage of seropositive dogs ranged from 7.1% to 100% in positive kennels. More than 40% of the seropositive dogs showed high titres. Sex had no significant effect on either seroprevalence or the category of the serum titre. The number of positive animals was significantly lower in the groups of prepuberal bitches and animals younger than 1.5 years. The majority of younger animals showed very high titres, suggesting recent contact with the virus. Our data show that CHV-1 is a common infection in breeding dogs in Piedmont. Vaccination is rarely performed but might be an option, because, although many animals of breeding age already show high antibody titres, seronegative pregnant bitches will be at high risk of contracting the infection due to viral circulation in kennels where the virus is enzootic.

Two New Sturgeon Species are Susceptible to Acipenser Iridovirus European (AcIV-E) Infection.

We report the first case of Acipenser iridovirus European (AcIV-E) infection in starry sturgeon (Acipenser stellatus) and in sterlet (A. ruthenus) reared in Northern Italy. During 2018, mortality began in A. stellatus and A. ruthenus specimens reared in co-habitation with Russian sturgeon positive for AcIV-E. Molecular analyses were done on the gills to amplify a fragment of the major capsid protein (MCP) gene using real-time PCR against AcIV-E. DNA of the positive samples was further sequenced and phylogenetic analyses were performed. The MCP gene sequences were highly similar to a virus previously identified in Italy (nucleotide identities between 99.38% and 99.69%). Phylogenetic analysis confirmed our hypothesis of passage of the virus from the infected Russian sturgeon. The detection of AcIV-E in new species of the Acipenseridae family may impact on sturgeon production, with relevant economic losses.

Serological survey of canine parvovirus 2 antibody titres in breeding kennels in northern Italy.

BACKGROUND: Current guidelines recommend parvovirus revaccination of adult dogs no more frequently than every 3 years. The aim of this study was to determine the prevalence of dogs showing protective serum antibody titres against canine parvovirus 2 in breeding kennels in Northern Italy and to assess the effect of time from vaccination and the sex of the dog on antibody titres. The study was carried out on 370 animals of different breeds kept in 33 breeding kennels. Antibodies to canine parvovirus 2 in serum samples were measured with an indirect immunoenzymatic assay validated by the manufacturer in relation to the 'gold standard' haemagglutination inhibition test. The number of months that had elapsed since the last vaccination was calculated for each animal and categorized into the following classes: < 12 months; 13-24 months; 25-36 months; 37-48 months; and > 49 months. RESULTS: The prevalence of 'unprotected' dogs was 4.6%. A satisfactory solid herd immunity was present in the majority of breeding kennels, although some vaccination failures were detected. A significant negative correlation was found between antibody titre and months since last vaccination. Comparable antibody titres were found in the first 3 years after vaccination. Although the antibody titre over time was not affected by the sex of the dog, 'unprotected' females had been vaccinated more recently than males with analogous low titres. CONCLUSIONS: Parvovirus revaccination of adult dogs every 3 years, as currently recommended, is also the appropriate recommendation for breeding kennels. Serological tests could be a useful tool to assess the effectiveness of vaccination.

Novel dolphin morbillivirus (DMV) outbreak among Mediterranean striped dolphins Stenella coeruleoalba in Italian waters.

An unusual mortality event (UME) of striped dolphins Stenella coeruleoalba occurred in the period July to December 2016 along the Italian Ionian coastline. We conducted a complete postmortem examination on 28 specimens and detected dolphin morbillivirus (DMV), by means of biomolecular analyses, in the target tissues of 17 animals. Unlike previous outbreaks occurring in the Mediterranean Sea in 2011 and 2013, we observed typical pathological changes suggestive of morbilliviral infection in an acute/subacute phase and immunohistochemical reactivity. The same findings were observed in 13 other specimens beached along the Italian coastline during 2016 with no temporal and geographical relationship with the ongoing epidemic outbreak. Molecular characterization and phylogenetic analysis showed that DMV sequences detected in Italy in 2016 clustered with those identified in Portugal and Galicia (Spain), representing a novel DMV strain of Atlantic origin which entered the Mediterranean Sea and affected a naïve striped dolphin population. DMV sequences detected in the previous Mediterranean outbreaks exhibited a marked genetic relatedness and diverged from those detected in cetaceans stranded along the Galician and Portuguese coasts since 2007.

CANINE DISTEMPER VIRUS AS AN EMERGING MULTIHOST PATHOGEN IN WILD CARNIVORES IN NORTHWEST ITALY.

Canine distemper (CD) may pose a serious threat to Alpine wild carnivores and affect their population dynamics. Since 2006, the strain Europe Wildlife 2006-09, a distinct CD virus subgroup within viral lineage Europe 1 (EU1) characterized by increased virulence and host range expansion, has been linked to multiple CD outbreaks in Alpine wild carnivores. The aim of this study was to fill knowledge gaps about ongoing Alpine outbreaks of CD. To do this, we report on the circulation of canine distemper virus (CDV) and outbreaks of CD in Alpine wild carnivores in northwest Italy. A specific diagnostic protocol applied to a sample of 548 wild carnivores collected between January 2013 and December 2015 revealed the circulation of CDV belonging to the EU1 lineage. All isolates were carriers of amino-acid mutations defining the cluster Europe Wildlife 2006-09. A self-maintained multihost pathogen system may have developed in northwest Italy in which interspecies transmission from red foxes (Vulpes vulpes) to other noncanid species enhanced pathogen maintenance in the system.

Mortality outbreak by perch rhabdovirus in European perch (Perca fluviatilis) farmed in Italy: Clinical presentation and phylogenetic analysis.

This work reports a mortality outbreak, occurred in 2015 and affecting juveniles of European perch (Perca fluviatilis L.) farmed in Italy. Perch rhabdovirus (PRV) was detected by viral isolation and biomolecular investigations. Phylogenetic analysis clustered our isolate into genogroup B, which also includes PRV isolates from Perca fluviatilis identified in France (2004-2009); diagnostic investigations also revealed opportunistic bacteria (Aeromonas hydrophila) and parasites (Chilodonella piscicola). Since, occasionally, PRV has been reported in the natural environment, which is often a source of eggs and broodstock for farms, it could be possible that both similar France and Italian isolate were imported from a same place elsewhere and have a common origin. Improving biosecurity measures (batch control) and disinfection of egg strings with an iodine-based solution helps prevent apparent vertical transmission of PRV.

The genome of Border disease virus genotype 8 from chamois by next generation sequencing.

Border disease virus (BDV) is widespread both in domestic small ruminants and wildlife. Here we report the genome of BDV genotype 8 from chamois, strain Italy­58987, obtained by next generation sequencing and the comparison with other pestiviruses. The sequence of 12,245 bp long was aligned to 22 pestivirus genomes and it showed a nt/aa similarity of 81.3/89.4% with BDV genotypes, and 65.9/67.8% with the other  pestiviruses. The genome showed a mean nt/aa similarity of 91.2/95.0% with three Swiss genomes closely related to the BDV­8 5'­UTR and Npro sequences. The identification of divergent BDV­8 isolates in North­Western Italy and in Switzerland suggests that this genotype may have been circulating in a wider area than previously supposed, and may have a high host adaptability.

A comparative study on subacute toxicity of arsenic trioxide and dimethylarsinic acid on antioxidant status in Crandell Rees feline kidney (CRFK), human hepatocellular carcinoma (PLC/PRF/5), and epithelioma papulosum cyprini (EPC) cell lines.

Arsenic (As) is a global contaminant of terrestrial and aquatic environments posing concern for environmental and human health. The effects of subacute concentrations of arsenic trioxide (AsIII) and dimethylarsinic acid (DMAV) were examined using Crandell Rees feline kidney (CRFK), human hepatocellular carcinoma (PLC/PRF/5), and epithelioma papulosum cyprini (EPC). Whole monolayer with suffering cells (confluence 100%, pyknosis and refractive cells; value scale = 2) led to identification of subacute As concentrations for the three cell lines. The selected AsIII concentrations were 1.33 µM for CRFK and 33.37 µM for PLC/PRF/5 and EPC, at 48 hr time point. The selected DMAV concentrations were 0.67 mM for PLC/PRF/5, 1.33 mM for CRFK, and 2.67 mM for EPC for 48 hr. Unlike the AsIII test, the three cell lines did not exhibit marked susceptibility to DMAV-mediated toxicity. Several oxidative stress biomarker levels, directly or indirectly associated with reactive oxygen species (ROS) elimination including superoxide dismutase, catalase, glutathione peroxidases, glutathione reductase, glutathione S-transferase, glyoxalase I, glyoxalase II, and total glutathione, were determined in the three cell lines at 24 and 48 hr. Antioxidant responses in metal-treated cells were significantly altered compared to controls, suggesting a perturbation of redox state. The weakening of antioxidant pathway in either healthy or tumoral cells was greater using AsIII than DMAV. Differences in level of several oxidative stress biomarkers suggest that the oxidative stress mechanism induced by AsIII is distinctly different from DMAV. Multifaceted mechanisms of action underlying ROS generation in tumor and nontumor cells versus AsIII and DMAV exposure are thus involved. Since As-mediated toxicity is quite complex, more data regarding both oxidant-enhancement and oxidant-lowering strategies may be useful to improve knowledge regarding the influence of As on human and animal cells.