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2022 ◽  
Vol 02 ◽  
Author(s):  
Nkem Torimiro ◽  
Oluwafemi B. Daramola ◽  
Richard K. Omole ◽  
Ifeyimika Z. Adesina

Introduction: The health challenges associated with cassava products as a common staple food for approximately 70% of Africans and part of Asia pose a looming danger due to Bacillus enterotoxins’ presence in the processing environment. Objective: This study investigated the presence of enterotoxigenic genes namely, Bacillus cereus enterotoxin T (bceT), hemolysin bl (hblC, hblD) and non-haemolytic enterotoxin (nheA, nheB and nheC) from Bacillus species isolated from soil of cassava processing environment. Methods: Soil samples from 20 cassava processing sites in Ile-Ife and Modakeke, Nigeria were collected and cultured on Nutrient agar at 37 ºC for 24 hours. Colonies phenotypically identified as Bacillus were identified using Bacillus-specific 16S rRNA-targeted PCR technique. Screened Bacillus spp were assessed for the presence of enterotoxigenic genes using PCR with previously reported primers. Results: A total of 100 Bacillus isolates were selected from this study with Bacillus macerans (33 %) showing the highest frequency of occurrence among the identified species, however, 74 isolates were molecularly confirmed as Bacillus. Amongst the 74 molecularly confirmed Bacillus isolates, 28 (37.84%), 35 (47.30 %) and 37 (50 %) has nhe, hbl and bceT genes respectively. Investigation showed that 42 (56.76 %) of the Bacillus species encoded at least one of the screened enterotoxin genes. Conclusion: The presence of these 3 sets of enterotoxin genes in Bacillus isolated from cassava processing sites calls for immediate attention as they could be pivotal in the release of toxins in cassava products, cause lethal effects via consumption. This study demonstrates the possibility of foodborne disease outbreaks in Bacillus toxin-laden cassava products processed under unhygienic conditions.


Toxin Reviews ◽  
2021 ◽  
pp. 1-14
Author(s):  
Amit Choudhary ◽  
Bharathi Mohindru ◽  
Ashok Kumar Karedla ◽  
Jaspal Singh ◽  
Pardeep K. Chhuneja

Toxics ◽  
2021 ◽  
Vol 10 (1) ◽  
pp. 4
Author(s):  
Tina Elersek ◽  
Matjaž Novak ◽  
Mateja Mlinar ◽  
Igor Virant ◽  
Nika Bahor ◽  
...  

Tyrosine kinase inhibitors (TKIs) are designed for targeted cancer therapy. The consumption of these drugs during the last 20 years has been constantly rising. In the zebrafish (Danio rerio) embryo toxicity test, we assessed the toxicity of six TKIs: imatinib mesylate, erlotinib, nilotinib, dasatinib, sorafenib and regorafenib. Imatinib mesylate and dasatinib induced lethal effects, while regorafenib, sorfenib and dasatinib caused a significant increase of sub-lethal effects, predominantly oedema, no blood circulation and formation of blood aggregates. The analyses of the changes in the expression of selected genes associated with the hormone system after the exposure to imatinib mesylate, dasatinib and regorafenib demonstrated that all three tested TKIs deregulated the expression of oestrogen receptor esr1, cytochrome P450 aromatase (cypa19b) and hydroxysteroid-dehydrogenase (hsd3b), regorafenib, and also thyroglobulin (tg). The expression of genes involved in the DNA damage response (gadd45 and mcm6) and apoptosis (bcl2) was deregulated only by exposure to regorafenib. The data indicate that common mechanisms, namely antiangiogenic activity and interference with steroidogenesis are involved in the TKI induced sub-lethal effects and potential hormone disrupting activity, respectively. The residues of TKIs may represent an environmental hazard; therefore, further ecotoxicological studies focusing also on the effects of their mixtures are warranted.


Author(s):  
Christina Tsitsimpikou ◽  
Nikolaos Georgiadis ◽  
Konstantinos Tsarouhas ◽  
Panagiotis Kartsidis ◽  
Eleni Foufa ◽  
...  

Over the last decades, human activities prompted the high production and widespread use of household chemical products, leading to daily exposure of humans to several chemicals. The objective of this study was to investigate the frequency of chemicals’ use by children and parents in Greece and estimate the level of risk awareness and understanding among them. A total of 575 parents and children were asked to answer an anonymous, closed-ended, validated, and self-administered questionnaire. One-third of the children and almost half of the parents participating in the study believed that commonly used chemical products do not pose any risk to human health or to the environment, despite the product labelling. The majority of both children (61.8%) and parents (70.6%) were informed about product safety via the product labelling. Around 20% in both groups could not differentiate between systemic toxicity and acute lethal effects depicted by pictograms on the label and milder hazards, such as skin irritation. Moreover, the information on hazard and precautionary statements appearing on the label was very poorly perceived. Therefore, as both children and parents seem not to clearly identify the hazards and risks arising from the use of everyday chemical products, targeted awareness policies should be implemented to support the safe use of household products.


2021 ◽  
Vol 226 ◽  
pp. 112861
Author(s):  
Tanita Pescatore ◽  
Valeria Di Nica ◽  
Antonio Finizio ◽  
Nicoletta Ademollo ◽  
Francesca Spataro ◽  
...  

Biology ◽  
2021 ◽  
Vol 10 (12) ◽  
pp. 1234
Author(s):  
Jadilson M. Damasceno ◽  
Lénia D. Rato ◽  
Tiago Simões ◽  
Inês F. C. Morão ◽  
Gabriela Meireles ◽  
...  

Sulfoxaflor is an insecticide belonging to the recent sulfoximine class, acting as a nicotinic acetylcholine receptor (nAChRs) agonist. There are few studies regarding sulfoxaflor’s toxicity to non-target organisms. The present study aimed to investigate the acute and sub-lethal effects of sulfoxaflor on Carcinus maenas by addressing survival, behaviour (feed intake and motricity), and neuromuscular, detoxification and oxidative stress, and energy metabolism biomarkers. Adult male green crabs were exposed to sulfoxaflor for 96 h and an LC50 of 2.88 mg L−1 was estimated. All biomarker endpoints were sampled after three (T3) and seven (T7) days of exposure and behavioural endpoints were addressed at T3 and day six (T6). Sulfoxaflor affected the feed intake and motricity of C. maenas at T6. From the integrated analysis of endpoints, with the increase in concentrations of sulfoxaflor, after seven days, one can notice a lower detoxification capacity (lower GST), higher LPO levels and effects on behaviour (higher motricity effects and lower feed intake). This integrated approach proved to be valuable in understanding the negative impacts of sulfoxaflor on green crabs, while contributing to the knowledge of this pesticide toxicity to non-target coastal invertebrates.


2021 ◽  
Author(s):  
◽  
Wan Fatma Zuharah Wan Musthapa

<p>The presence of predators can shape the population dynamics of prey. Here, I evaluated the influence of predators on mosquito populations by direct effects through predation, and indirect effects through sub-lethal responses. The predator under investigation was the backswimmer Anisops wakefieldi. I first quantified the relationship between mosquito and predator populations in animal drinking water troughs, and correlated their abundance with water volume and environmental factors. Logistic regression indicated that the presence of mosquitoes was primarily affected by three factors; predator numbers, week of observation, and water volume. A translocation experiment was established to understand the pre- and post-treatment effects on mosquito survival after exposure to the predator Anisops wakefieldi. The presence of these predators in water troughs significantly decreased subsequent survival of mosquito prey within two days posttranslocation. A major hypothesis in invasion ecology suggests that native predators have less impact on exotic species relative to native prey species, enabling exotic species to establish and thrive in novel environments. This is the "escape from natural enemies" hypothesis. Contrary to this hypothesis A. wakefieldi, a native New Zealand predator, showed a greater preference, and consumed more of the exotic mosquito Aedes (Ochleratatus) notoscriptus compared to the native (Culex pervigilans) mosquito larvae. Anisops wakefieldi exhibited a decelerating Type II functional response for both prey species, but consumed more exotic mosquito species at high prey densities and displayed higher attack rates. The effects of the preference of this predator on mosquito behaviour were examined. In the presence of predators the exotic species, Ae. notoscriptus, demonstrated significantly higher levels of "thrashing" behaviours, apparently making itself more obvious to the predators. In contrast Cx. pervigilans fulfilled the "threat sensitivity" hypothesis by altering its behaviour towards "resting", known to be the best strategy for avoiding predators. In addition to lethal effects, predators can substantially alter prey populations by means of sub-lethal influences. To further our understanding of how predators limit mosquito abundance, I developed an experiment based on adult mosquito oviposition. I predicted that the New Zealand native mosquito, Cx. pervigilans would likely avoid containers with A. wakefieldi or their kairomones. Contrary to our predictions, Cx. pervigilans appeared to ignore the presence of predators and their kairomones when choosing oviposition habitats and the number of egg rafts was not significantly affected by the density of predators. Culex pervigilans eggs from the oviposition experiment were reared in two different laboratory conditions: (A) in clean water without any traces of predators, or (B) in water with the same treatments as in field. This experiment was established in order to have better understand on what happens to the next generation after exposure to A. wakefieldi predators or their kairomones. Sub-lethal effects were still apparent in the developing larvae. I observed a significant reduction in the survival rate of Cx. pervigilans in the presence of predators and their kairomones, even when the eggs were only exposed briefly to water containing either predators or kairomones in the field, and were then reared in clean water without any traces of the predator. No effect was observed on the sex ratio of Cx. pervigilans, or the development times of each life stage. Overall, this thesis has highlighted the importance of predators in influencing mosquito populations, not only through direct predation, but also in indirect and sub-lethal ways. This study may have implications for the dynamics of other predator-prey systems. Despite this, we are only beginning to understand the complex interactions between predators and prey.</p>


2021 ◽  
Author(s):  
◽  
Wan Fatma Zuharah Wan Musthapa

<p>The presence of predators can shape the population dynamics of prey. Here, I evaluated the influence of predators on mosquito populations by direct effects through predation, and indirect effects through sub-lethal responses. The predator under investigation was the backswimmer Anisops wakefieldi. I first quantified the relationship between mosquito and predator populations in animal drinking water troughs, and correlated their abundance with water volume and environmental factors. Logistic regression indicated that the presence of mosquitoes was primarily affected by three factors; predator numbers, week of observation, and water volume. A translocation experiment was established to understand the pre- and post-treatment effects on mosquito survival after exposure to the predator Anisops wakefieldi. The presence of these predators in water troughs significantly decreased subsequent survival of mosquito prey within two days posttranslocation. A major hypothesis in invasion ecology suggests that native predators have less impact on exotic species relative to native prey species, enabling exotic species to establish and thrive in novel environments. This is the "escape from natural enemies" hypothesis. Contrary to this hypothesis A. wakefieldi, a native New Zealand predator, showed a greater preference, and consumed more of the exotic mosquito Aedes (Ochleratatus) notoscriptus compared to the native (Culex pervigilans) mosquito larvae. Anisops wakefieldi exhibited a decelerating Type II functional response for both prey species, but consumed more exotic mosquito species at high prey densities and displayed higher attack rates. The effects of the preference of this predator on mosquito behaviour were examined. In the presence of predators the exotic species, Ae. notoscriptus, demonstrated significantly higher levels of "thrashing" behaviours, apparently making itself more obvious to the predators. In contrast Cx. pervigilans fulfilled the "threat sensitivity" hypothesis by altering its behaviour towards "resting", known to be the best strategy for avoiding predators. In addition to lethal effects, predators can substantially alter prey populations by means of sub-lethal influences. To further our understanding of how predators limit mosquito abundance, I developed an experiment based on adult mosquito oviposition. I predicted that the New Zealand native mosquito, Cx. pervigilans would likely avoid containers with A. wakefieldi or their kairomones. Contrary to our predictions, Cx. pervigilans appeared to ignore the presence of predators and their kairomones when choosing oviposition habitats and the number of egg rafts was not significantly affected by the density of predators. Culex pervigilans eggs from the oviposition experiment were reared in two different laboratory conditions: (A) in clean water without any traces of predators, or (B) in water with the same treatments as in field. This experiment was established in order to have better understand on what happens to the next generation after exposure to A. wakefieldi predators or their kairomones. Sub-lethal effects were still apparent in the developing larvae. I observed a significant reduction in the survival rate of Cx. pervigilans in the presence of predators and their kairomones, even when the eggs were only exposed briefly to water containing either predators or kairomones in the field, and were then reared in clean water without any traces of the predator. No effect was observed on the sex ratio of Cx. pervigilans, or the development times of each life stage. Overall, this thesis has highlighted the importance of predators in influencing mosquito populations, not only through direct predation, but also in indirect and sub-lethal ways. This study may have implications for the dynamics of other predator-prey systems. Despite this, we are only beginning to understand the complex interactions between predators and prey.</p>


2021 ◽  
pp. 107051
Author(s):  
Shuo Wang ◽  
Sofia Lopez ◽  
Nader El Ahmadie ◽  
Andrew S. Wengrovitz ◽  
Jade Ganter ◽  
...  

Author(s):  
Florian J. Egloff ◽  
James Shires

Abstract Transformations in state violence are intimately associated with technological capacity. Like previous era-defining technologies, global digital networks have changed state violence. Offensive cyber capabilities (OCCs) appear to constitute a major technological development that offers the potential for reducing state violence. This article asks: are OCCs really the better angels of our digital nature? Current scholarship in strategic studies, adopting a narrow definition of violence, conceives of OCCs as largely non-violent. This ignores how technology has given rise to new forms of harm to individuals and communities, particularly in the context of violent state repression. We propose using an expanded definition of violence, including affective and community harms, and argue that OCCs relocate, rather than reduce, state violence towards non-bodily harms. Even though their lethal effects are limited, OCCs are not, as is supposed, a non-violent addition to state arsenals. This conclusion has important implications for international affairs, including re-orienting defensive cybersecurity efforts and altering calculations around the perception of OCCs by adversaries.


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