On November 2015, one of Brazil's most important watersheds was impacted by the mine waste from Fundão dam collapse in Mariana. The mine waste traveled over 600 km along the Doce River before ...reaching the sea, causing severe devastation along its way. Here we assessed trace element concentrations and cytogenotoxic effects of the released mine waste. Water samples were collected along the Doce River ten days after the disaster in two impacted sites and one non-impacted site. Sampling points were located hundreds of kilometers downstream of the collapsed dam. Water samples were used for trace element quantification and to run an experiment using Allium cepa to test cytogenotoxicity. We found extremely high concentrations of particulate Fe, Al, and Mn in the impacted sites. We observed cytogenotoxic effects such as alterations in mitotic and phase indexes, and enhanced frequency of chromosomal aberrations. Our results indicate interferences in the cell cycle in impacted sites located hundreds of kilometers downstream of the disaster. The environmental impacts of the dam collapse may not only be far-reaching but also very likely long-lasting, because the mine waste may persist in the Doce River sediment for decades.
•Higher concentrations of particulate metals were found in impacted sites.•Cytogenotoxic effects were found in the impacted sites.•Mining waste affected genetic aspects of Allium cepa.•Impacts of the tragedy are far-reaching and long-lasting.
Abstract Herbicides are agrochemicals applied in the control of weeds. With the frequent and repetitive use of these substances, serious problems have been reported. Compounds of natural origin and ...their derivatives are attractive options to obtain new compounds with herbicidal properties. By aiming to develop compounds with potentiated herbicidal activity, phenoxyacetic acids were synthesized from eugenol and guaiacol. The synthesized compounds were characterized and the herbicidal potential of phenoxyacetic acids and precursors was evaluated through bioassays regarding the germination and initial development of Lactuca sativa and Sorghum bicolor seedlings, with the induction of DNA damage. The induction of changes in the mitotic cycle of meristematic cells of roots of L. sativa was also analyzed. At the concentration of 3 mmol L-1, phenols and their respective phenoxyacetic acids presented phytotoxic and cytotoxic activities in L. sativa and S. bicolor. Eugenol and guaiacol also presented genotoxic action in L. sativa. The toxic effect of eugenoxyacetic acid was more pronounced in L. sativa than in S. bicolor, similar to the commercial 2,4-D herbicide. Molecular properties of the phenols and their derivatives phenoxyacetic acids were compared with the ones obtained for the herbicide 2,4-D, where it was found a correlation between their molecular properties and bioactivity.
Jatropha curcas L. (Euphorbiaceae) is important for biofuel production and as a feed ingredient for animal. However, the presence of phorbol esters in the oil and cake renders the seeds toxic. The ...toxicity of J. curcas oil is currently assessed by testing in animals, leading to their death. The identification of toxic and nontoxic improved varieties is important for the safe use of J. curcas seeds and byproducts to avoid their environmental toxicity. Hence, the aim of this study was to propose a short-term bioassay using a plant as a model to screen the toxicity of J. curcas oil without the need to sacrifice any animals. The toxicity of J. curcas oil was evident in germination, root elongation and chromosomal aberration tests in Lactuca sativa. It was demonstrated that J. curcas seeds contain natural compounds that exert phyto-, cyto- and genotoxic effects on lettuce, and that phorbol esters act as aneugenic agents, leading to the formation of sticky chromosomes and c-metaphase cells. In conclusion, the tests applied have shown reproducibility, which is important to verify the extent of detoxification and to determine toxic doses, thus reducing the numbers of animals that would be used for toxicity tests.
Spent pot liner (SPL) is a solid waste generated during the primary smelting of aluminum, and its toxicity is attributed to the presence of fluoride, cyanide, and aluminum salts, which can be leached ...into aquatic ecosystems. Since the effects of this waste on aquatic life forms have not yet been investigated, the objective of our study was to evaluate the toxicity of simulated leachates of SPL on zebrafish (
Danio rerio
). Animals were exposed to 0 (control), 0.32, 0.64, or 0.95 g L
−1
of SPL for 24, 72, and 96 h, and genotoxicity was accessed through micronucleus and comet assays. All of the tested treatments induced DNA fragmentation, and the observed frequency of micronuclei and damaged nucleoids generally increased with increasing SPL concentration. The highest frequency of micronuclei (3.3 per 3000 erythrocytes) was detected after 96 h of exposure with 0.95 g L
−1
SPL. In the comet assay, nucleoids classified with highest level of damage in relation to the control were observed principally after 24 and 96 h of exposure. The data obtained in this study confirm the genotoxicaction and mutagenic potential of SPL and indicate that open-air deposits of the waste material could represent a health risk to humans and ecosystems alike.
Guava (Psidium guajava L.) is a plant often employed in popular medicine. Recently several studies have alerted about the toxicity of substances present in medicinal plants, which can pose risks to ...the human health. In this sense, the present work aimed to investigate the phytotoxic, cytotoxic and genotoxic action of three guava varieties - Paluma, Pedro Sato and Roxa ("purple") - on the plant test system Lactuca sativa L. Thus, macro- and microscopic evaluations were carried out for five infusion concentrations (2.5, 5.0, 10.0, 20.0 and 40.0 g.L(-1)) prepared from each variety. Distilled water was used as negative control. Chromatographic and spectroscopic analysis by HPLC-PAD indicated that the chemical composition of the infusion of Roxa is different than that of the infusions of the varieties Paluma and Pedro Sato. It was observed that seed germination and root growth in L. sativa exposed to infusions decreased with increasing infusion concentration, regardless of the tested cultivar. For the mitotic index, no statistical differences were observed. On the other hand, a significant increase in the frequency of cell cycle alterations was verified, especially for the highest concentrations tested. The cytogenotoxic effect was significant. Therefore, guava should not be used indiscriminately in popular medicine.
Infusions of the leaves and seeds of Annona crassiflora Mart. are commonly employed in the treatment of diarrhoea, snakebites, tumours and disorders of the hair and scalp. The aim of the present ...study was to investigate the cytotoxic and genotoxic properties of ethanolic extracts of A. crassiflora by evaluating their effects on germination, root elongation, chromosome structure and the cell division of Lactuca sativa (lettuce). The experiment followed a randomized design involving the treatment of L. sativa seeds with ethanolic extracts from leaves and seeds of A. crassiflora applied at ten concentrations (0.0125, 0.025, 0.05, 0.1, 0.2, 0.4, 0.6, 0.8, 1.0, and 1.2 mg/L) and with five repetitions per treatment. Seeds of L. sativa exposed for 48 h to A. crassiflora leaf extract at concentrations ≥ 0.1 mg/L, or to seed extracts at concentrations ≥ 0.2 mg/L, showed germination percentages that were significantly (p < 0.05) lower than those of seeds exposed to aqueous ethanol control. Exposure of L. sativa seedlings to leaf (but not seed) extracts of A. crassiflora produced significant (p < 0.05) reductions in the mitotic indices of root meristem cells of lettuce and induced chromosome and nuclear abnormalities in the root cells. The presence of chromosome stickiness, bridges, fragments, laggard chromosomes and nuclear condensation were also observed. The cytogenetic effects observed suggest that folkloric medicines prepared with extracts of the leaves or seeds of A. crassiflora should be employed with caution.
Industrial waste usually contains complex mixtures of mutagenic chemicals. Spent Pot Liner (SPL) is a complex solid waste from the aluminum industry, which is composed of organics, fluoride salts, ...inorganic cyanides, metals, and sodium. Due to the toxicity of these compounds, this study sought to use cytogenetics and flow cytometry to assess the effects of SPL on cell cycle parameters and DNA content in meristematic cells of Allium cepa. Three concentrations of leachates from SPL-soil mixtures were used for the study: 0, 10, and 25%. Roots were collected and analyzed after 4, 8, 12, 24, and 36 h of exposure to the above SPL leachates. The results showed an overall mitodepressive effect accompanied by an increased percentage of condensed nuclei and genomic instability as evidenced by the presence of cellular/chromosomal abnormalities. Terminal deoxynucleotidyl transferase dUTP nick end labeling revealed nuclei with fragmented DNA, a marker of programmed cell death. This study also addressed the question of reversibility of the effects of SPL and found that 36 h of exposure to 25% SPL seemed to be the point at which the effects on the induction of apoptosis became irreversible.
► SPL is a solid waste from aluminum industry. ► It can be dumped on landfills and leached with water. ► Cytogenetics and flow cytometry assessed the effects of SPL on cell cycle and DNA. ► SPL causes mitodepressive effects and genomic instability on cells. ► DNA fragmentation revealed by TUNEL assay is a consequence of SPL.
Imperfect adherence is a major barrier to effective primaquine radical cure of Plasmodium vivax. This study investigated the effect of reduced adherence on the risk of P. vivax recurrence.
Efficacy ...studies of patients with uncomplicated P. vivax malaria, including a treatment arm with daily primaquine, published between January 1999 and March 2020 were identified. Individual patient data from eligible studies were pooled using standardized methodology. Adherence to primaquine was inferred from i) the percentage of supervised doses and ii) the total mg/kg dose received compared to the target total mg/kg dose per protocol. The effect of adherence to primaquine on the incidence of P. vivax recurrence between days 7 and 90 was investigated by Cox regression analysis.
Of 82 eligible studies, 32 were available including 6917 patients from 18 countries. For adherence assessed by percentage of supervised primaquine, 2790 patients (40.3%) had poor adherence (≤ 50%) and 4127 (59.7%) had complete adherence. The risk of recurrence by day 90 was 14.0% 95% confidence interval: 12.1-16.1 in patients with poor adherence compared to 5.8% 5.0-6.7 following full adherence; p = 0.014. After controlling for age, sex, baseline parasitaemia, and total primaquine dose per protocol, the rate of the first recurrence was higher following poor adherence compared to patients with full adherence (adjusted hazard ratio (AHR) = 2.3 1.8-2.9). When adherence was quantified by total mg/kg dose received among 3706 patients, 347 (9.4%) had poor adherence, 88 (2.4%) had moderate adherence, and 3271 (88.2%) had complete adherence to treatment. The risks of recurrence by day 90 were 8.2% 4.3-15.2 in patients with poor adherence and 4.9% 4.1-5.8 in patients with full adherence; p < 0.001.
Reduced adherence, including less supervision, increases the risk of vivax recurrence.
Abstract Cannabidiol (CBD) has been studied for substance use disorders treatment due to its anxiolytic effects, for sleep, appetite, reduction of craving, and maintenance of abstinence. The study ...aims to assess CBD’s feasibility, safety/tolerability, and preliminary efficacy compared to pharmacological treatment as usual for reducing crack use in people with crack use disorder (CUD) and investigate other parameters: adverse events, physical health symptoms, and craving. A double-blind, randomized clinical trial (RCT) with two treatment arms (CBD and control group) was conducted. Ninety participants were randomized and 73 were allocated: 37 control group and 36 CBD group for a 10-week treatment, comparing CBD (600 mg) with three drugs (fluoxetine, valproic acid, and clonazepam). The per-protocol analysis of participants who did not deviate from the study protocol compared the control and CBD treatment groups. Thirty-four completed at least half of the study and 25 finished. Participants attended weekly meetings for the study procedures (e.g., to receive the medication and provide urine for toxicological tests). Inter-group differences were performed with the Mann–Whitney test, the Wilcoxon test for differences intra-group, and Pearson’s Chi-square test or Fisher’s exact test to compare inter-group demographic data. The significance level was 5%. A “veracity index” (VI) was created as counterevidence (questionnaire data vs. the toxicological test result). Medications were considered safe/tolerable. The CBD group presented significantly fewer adverse events compared to the control group e.g., dizziness ( p = 0.001), memory impairment ( p = 0.043), which performed better in the reduction of clinical and psychiatric complaints ( p = 0.008). In the intra-group analyses, the CBD group performed better in more parameters than the control group e.g., reducing crack use ( p = 0.016; T0 to T1). Data questionnaires were reliable regarding the use/non-use of crack (VI = 0.787). CBD is a safe/tolerable product. The CBD group manifested fewer adverse events than the control group, which had better clinical and psychiatric complaints results. There are some advantages for the CBD group in the intra-group analysis. Drug use self-report methodologies can be reliable. Trial registration details: This study is registered with Universal Trial Number (UTN) code: U1111-1234-0806. Available at https://ensaiosclinicos.gov.br/rg/RBR-4stgs8 ( Effect of cannabidiol in the treatment of crack dependents )
Pregnant and postpartum women infected by COVID-19 are at increased risk of adverse outcomes, including negative effects on their mental health. Brazilian maternal mortality rate due to COVID-19 is ...2.5 times higher than overall mortality rates. This study aimed to understand how pregnant/postpartum women experienced the COVID-19 suspicion/investigation or confirmed infection in different Brazilian cities, the pandemic's consequences to women and their families, and their needs to improve maternal health services during public health emergencies.
We conducted a qualitative study with 27 women with COVID-19 and 6 of their family members, as part of a multicenter study among 15 maternity hospitals in Brazil. We applied in-depth interviews through telephone calls when women received the diagnostic or had a suspect infection and after 60 days. Another semi-structured interview was applied to their close family members. The interviews were considered through thematic analysis.
From the thematic content analysis three major themes emerged from the first and second interviews: (Cucinotta and Vanelli, 2020) assistance received by the woman and newborn in the medical services; (World Health Organization (WHO) 2021) stigma/fear of contamination from health workers and from family and friends reported by the women; (Allotey et al., 2020) the COVID-19 pandemic impact.
Before the availability of the COVID-19 vaccine, pregnant women experienced fear of death, hospitalization, quarantine, loss of family members, and financial repercussions, resulting in physical, psychological, and socioeconomic impacts on these women's lives.
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