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Mosquitoes, as hematophagous ectoparasites, are significant pests and vectors of numerous pathogens, causing diseases such as dengue, lymphatic filariasis, malaria, chikungunya, and Japanese encephalitis in India. This study investigates the potential of natural insecticides derived from plants to combat mosquito populations, focusing on botanical extract from the leave of Sphaeranthus indicus. Specifically, the hexane extract of S. indicus exhibited notable efficacy against Aedes aegypti and Culex quinquefasciatus mosquitoes. The research entailed the extraction, fractionation, and structural identification of active compounds through spectroscopic analysis. Among ten fractions isolated, fraction 4 demonstrated the highest mosquitocidal activity, leading to the identification of β-isocostic acid as the primary active compound. The study's biological assays included ovicidal, larvicidal, and pupicidal tests, revealing that β-isocostic acid exhibited significant efficacy, with ovicidal activity rates of 75.2% and 78.2% at 2 ppm against Ae. aegypti and Cx. quinquefasciatus, respectively. Larvicidal and pupicidal assays further confirmed the potent activity of β-isocostic acid, with LC₅₀ values of 1.02 ppm and 0.96 ppm against Ae. aegypti and Cx. quinquefasciatus larvae, and 1.20 ppm and 1.14 ppm against Ae. aegypti and Cx. quinquefasciatus pupae respectively. The isolated compound demonstrated comparable efficacy to azadirachtin and temephos, indicating its potential as a natural mosquitocidal agent. This research underscores the importance of exploring botanical sources for developing effective and environmentally sustainable mosquito control strategies, particularly in light of increasing resistance to synthetic insecticides. The findings suggest that β-isocostic acid could serve as a viable alternative to chemical mosquitocides, contributing to integrated vector management programs.

As global warming and water eutrophication, the multiple proliferation of harmful cyanobacteria can form algal blooms and cause serious ecological problems. In recent years, the large-scale and persistent cyanobacterial blooms occur frequently worldwide and have attracted widespread attention due to the harmful impacts. Among these harmful bloom-forming cyanobacteria, the ecological and toxicological impacts of planktonic cyanobacteria have been extensively studied. However, research on the ecological risks and adverse effects of harmful benthic cyanobacteria is lagging. Filter-feeding fish could suffer from more toxic stimuli than other fish due to their special feeding habits. To investigate and compare the complex toxic effects of different kinds of harmful cyanobacteria on fish, three different-sized (i.e. small, medium, and large) juvenile silver carp (Hypophthalmichthys molitrix) and bighead carp (Aristichthys nobilis) were exposed to cyanobacterial blooms-related density (1 × 10⁶ cells/mL) of Microcystis aeruginosa (i.e. generating microcystins) and Oscillatoria sp. (i.e. generating cylindrospermopsin) for 3 d, after which biomarkers of oxidative stress and inflammation in the liver of fish were detected. The silver carp and bighead carp can effectively ingest Microcystis cells but cannot effectively ingest Oscillatoria cells through the measurement of the levels of cyanotoxins. Both Microcystis and Oscillatoria cells can induce different levels of oxidative stress and inflammatory responses in the liver of these juvenile filter-feeding fish via altering the biochemical parameters of the antioxidant system (e.g. superoxide dismutase activity) and immune system (e.g. interleukin-1β level). Therefore, our research identified potential data gaps that how the different types of cyanobacteria induce toxic effects in the liver of juvenile filter-feeding fish in a short time. This study contributes to a better understanding of the short-term adverse effects of different cyanobacterial species on juvenile fish, suggesting that the benthic toxic cyanobacteria-induced ecological and health risks require further attention.

The systematic annotation of novel peptides found in the venom of scorpions needs revision. The commonly used two-letter acronym with the initials of the genus and the species is not discriminative and induces confusion. A new universal five-letter abbreviated code is here proposed. With this code, every species can be unambiguously identified. The code contains the initial capital letter of the genus, followed by four letters from the species. This code discriminates the large majority of the species. For the few others from the same genus and with coinciding initial letters of the species name, a change in the fifth letter ensures uniqueness. For scorpions belonging to different genera with identical initial letters and the same exact species name, a five-letter identifier can be generated by using two letters from the genus (in uppercase) and three letters from the species (in lowercase). Following this proposal, the peptides belonging to all scorpion species can be properly annotated.

The present study focused on assessing the impact of clove oil on adult snails, specifically Eobania vermiculata, due to their detrimental effects on plants and crops. Our investigation aimed to explore both the lethal and sub-lethal toxicity of clove oil under laboratory and field conditions, with the goal of elucidating the mechanisms underlying its toxic effects on E. vermiculata. Snails were exposed to various concentrations of clove oil for one week to determine the LC₅₀, which was calculated to be 5.25% v/v (4.029-6.087). To investigate the molluscicidal effects of clove oil, snails were divided into three groups: control, vehicle-treated (1 % Tween 80), and treated group exposed to sub-lethal concentration (½ LC₅₀) of clove oil for one week. Compared to the control group, the exposure to ½ LC₅₀ of clove oil for 7 days resulted in significant increases in alkaline phosphatase (ALP), malondialdehyde (MDA), catalase (CAT), and superoxide dismutase (SOD). Conversely, the level of acetylecholnstrase (AChE) and glutathione peroxidase (GPx) was decreased. Furthermore, testosterone (T) and estrogen (E) levels were significantly reduced. Histological and ultrastructural studies revealed significant tissue disorganization. Additionally, Comet assay results confirmed the genotoxic potential of clove oil on E. vermiculata. Field trials demonstrated a higher reduction in snail populations in plots treated with methomyl (80% and 92% reduction after 7 and 14 days, respectively) compared to those treated with clove oil (64% and 73% reduction, respectively). While slightly less effective than methomyl, clove oil offers a valuable, natural, and residue-free alternative for eco-friendly snail management.

We evaluated the efficacy of freeze-dried Bothrops-Lachesis-Crotalus antivenom and liquid Crotalus antivenoms to neutralize Crotalus durissus ruruima (Cdr) venom (Roraima, Brazil) comparing with C. d. terrificus (Cdt) venom. Lethal and phospholipase A₂ activities were similar between both spp. Crotamine was negative and individual Cdr venoms induced hemorrhage in mice. It was lower coagulant than Cdt venom. Only Bothrops-Lachesis-Crotalus antivenom neutralized all biological activities evaluated, suggesting that it could be used in snakebites in this region.

The clinical evolution and management of a 22-yr-old male envenomed by a captive female inland taipan, Oxyuranus microlepidotus (McCoy, 1879), Elapidae, at a public educational reptile exhibit (Florida, USA) is reported. The patient was bitten (quick 'bite and release') in the right hand between digits #3 and 4 while performing captive maintenance. The victim did not attempt any first aid, but urgently presented to the local hospital within 25 mins post-bite. The patient had an unremarkable medical/surgical history including no previous envenoming/treatment with antivenom. Within approximately 5 mins post-bite he reported experiencing transient loss of consciousness/syncope, altered sensorium, nausea, dull headache, weakness, and "severe" bite site pain. Laboratory investigations revealed profound defibrinating coagulopathy including thrombocytopenia; there was only mildly elevated creatine kinase and renal function remained within normal limits. The patient's clinical evolution included cranial nerve palsies manifested as dysconjugate gaze, persistent, but minor, bite site bleeding, asthenia and reported myalgia as well as prolonged intense bite site pain. He was successfully and uneventfully treated with four vials of Australian polyvalent antivenom and one vial of taipan monovalent; all were expired products with expiration dates ranging from one month to 38 years. Effective antivenom therapy might have been achieved with only 2, possibly 3 vials; however, concerns about reduced efficacy of the long-expired antivenom (4/5 vials were expired 18-38 years) and persistent bite site bleeding/pain contributed to the provision of the additional vials. The patient recovered sufficiently for discharge in 48 h; there were no sequelae. There have been approximately 12 formally documented cases of O. microlepidotus envenoming and selected, detailed examples of these are briefly considered and compared with the clinical evolution of our patient; patient-centred recommendations for management of Oxyuranus spp. envenoming are discussed. The need for advanced preparedness and an action plan for any institution/collection that contains non-native, medically significant venomous species is emphasised, and a general recommended approach is outlined.

Detailed cases of envenoming by a non-front-fanged snake (NFFS) from North, Central, and South America have had limited representation in the toxicology and toxinology literature. The NFFS, Conophis lineatus, has been reported to deliver bites that resulted in moderately severe envenoming. However, most of these reported cases have been via personal communication, or self-reported and lacking in detailed medical evaluations. Reported here is a case of an amateur naturalist who was traveling in Mexico and was envenomed following extensive protracted bites to both hands from a wild Conophis lineatus concolor. There was rapid development of extensive localized edema, intense pain, and ecchymoses. The patient was transported to a hospital and after arrival the administration of antivenom was considered due to the severe appearance of local symptoms. The patient requested the medical team contact a consultant toxinologist who advised against the administration of antivenom because of the absence of any supporting evidence demonstrating therapeutic benefit in treating envenoming by C. l. concolor. Consequently, all treatments were limited to supportive symptomatic care. Despite the development of prominent localized symptoms, all laboratory evaluations, including coagulopathy assessment values, revealed no remarkable abnormal alterations. The patient was discharged after two days and symptoms gradually resolved with two months of supportive care.

The structural similarity between aristolactams (ALs) and aristolochic acids (AAs) raises constant concerns about the safety of ALs-containing plants. Natural ALs are distributed more extensively than AAs, leading to a higher risk of ALs exposure in daily consumption. This study aimed to evaluate and compare the in vitro nephrotoxicity on human renal tubular epithelial cells (HK-2 cells) of eight natural ALs with different substituents on the phenanthrene ring and amide ring, including aristolactam Ⅰ (AL Ⅰ), AL BⅡ, velutinam, AL AⅡ, sauristolactam, AL AⅠa, AL FⅠ and N-methyl piperolactam A. Their IC₅₀ values of cell viability were tested by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, and enzyme-linked immunosorbent assay (ELISA) was used to determine the levels of kidney injury molecule-1 (KIM-1), transforming growth factor-β1 (TGF-β1) and fibronectin (FN). The reactive oxygen species (ROS) assay was used to detect the intracellular oxidative stress level. The results showed that the eight ALs all had specific nephrotoxicity on HK-2 cells. Particularly, AL Ⅰ, AL BⅡ and velutinam exhibited more potent cytotoxicity on HK-2 cells (IC₅₀ = 2.49-2.78 μM) than the other five ALs (IC₅₀ = 12.33-43.84 μM). The structure-toxicity relationships indicated that both methylenedioxy (-OCH₂O-) and methoxy (-OCH₃) were positively contributing functional groups of ALs on nephrotoxicity, while the hydroxy group (-OH) and methyl substitution on nitrogen (N-CH₃) accounted for a detrimental effect conversely. Consistent with this structure-toxicity relationship, the eight ALs increased KIM-1 levels in the same trend as their cytotoxicity at the same concentration of 2.5 μg/mL, associating with different levels of ROS generation. And the four most toxic ALs, AL Ⅰ, AL BⅡ, velutinam and AL AⅡ, could also induce fibrosis by increasing TGF-β1 and FN levels.

Amanita pantherina poisoning is a rare event poorly described. The clinical picture is usually associated with the one of A. muscaria, but A. pantherina contains more muscimol causing more often coma. We describe a case of severe coma and seizures after A. pantherina ingestion. A woman of 56 years old was found at home unresponsive with miosis, clonic movements of four limbs, normal respiratory and cardiovascular functions and without cerebral ischemic symptoms. Her husband reported mushrooms ingestion 4 hours earlier that were picked up in the home garden and believed to be Macrolepiota procera. Unenhanced brain CT and cerebral CT angiography were normal. Blood tests were within normal range, including troponin I, creatine phosphokinase and lactate. Toxicological screening was negative for methadone, ecstasy, amphetamines, barbiturate, cannabinoids, cocaine, opioids and benzodiazepines. Suspecting ingestion of A. pantherina, gastrointestinal decontamination was done. Mycological examination of residual stems of the ingested mushrooms identified A. pantherina, and evaluation of photos of the same mushrooms growing in their garden confirmed the species. Electroencephalogram confirmed epileptiform activity and levetiracetam 3.000 mg/day was started. The patient was always hemodynamically stable but daily neurologic wake-up test highlighted the presence of agitation and clonic movements of the limbs up to the 7th day of hospitalization. Levetiracetam was tapered and stopped after two months based on neurological improvement. The patient recovered without sequelae. Amanita pantherina poisoning is a rare event and clinical picture of convulsions and coma often guides the diagnosis towards organic pathologies. The latter should be excluded first but an accurate anamnesis should also consider mushrooms consumption. Gastrointestinal decontamination may be the only therapy for reducing toxins absorption and clinical severity. Our patient had acute severe neurological effects lasted many days, but she completely recovered with intensive treatment and levetiracetam administration.

Nicotine is a toxic and addictive alkaloid found in tobacco and tobacco products that is harmful to human health and is an environmental pollutant. Nicotine-degrading microorganisms are unique microorganisms with the ability to use nicotine molecules as their sole source of nitrogen and carbon needed for growth. They are capable of degrading nicotine into less toxic or non-toxic metabolites. This review describes the environment's primary nicotine contamination sources and potential hazards. It also summarizes various types of nicotine-degrading microorganisms, their optimal culture conditions, and degradation efficiency. Four different catabolic pathways of nicotine in microorganisms are discussed, and the applications of nicotine-degrading microorganisms in different fields, such as the tobacco, pharmaceutical, and environmental protection industries, are outlined. This review describes the hazards of nicotine and the current research and application of nicotine-degrading microorganisms. It provides a theoretical reference for future research on nicotine-degrading microorganisms and their applications.