Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 198
Filter
1.
Heliyon ; 10(14): e34808, 2024 Jul 30.
Article in English | MEDLINE | ID: mdl-39149005

ABSTRACT

Waste liquid mercury generated as a by-product of the Merrill-Crowe process in gold mining and recovered from mercury-containing waste must be stabilized for secure storage or disposal. This study developed a procedure for mercury stabilization. A ball mill with a 0.5 m3 capacity and a rotational speed of 43 rpm was used to stabilize the residual mercury with sulfur. The treatments were conducted for 30, 60, and 90 min at mercury: sulfur molar ratios of 1.0, 0.8, and 0.67. The ball loading ratio was 7.0 with residual mercury, and the temperature was below 40 °C. The treatment efficiency was evaluated by measuring the concentrations of mercury and other metals using the Toxicity Characteristic Leaching Procedure (TCLP), examining the stabilized residual mercury by X-ray diffraction, and conducting bioassays on Daphnia magna and Lactuca sativa. Principal component analysis (PCA) was performed on the aforementioned variables. The 90-min treatment, with a mercury-to-sulfur molar ratio of 0.67, stabilized mercury mainly as cinnabar compared with the other treatments and presented leachate mercury values below the detection limit <0.003. The leachate from the treatments also showed values of 21.28-38.44 toxic units, classified as very toxic, and generated toxicity, particularly for D. magna, because of the presence of other metals such as Al, Ba, B, Ca, Cu, Cr, Fe, Mn, Ni, and Zn. The variability of the residues in the PCA analysis was explained by the treatment effect and the presence of other metals in the residual mercury. The stabilized residual mercury obtained was classified as non-hazardous and could be stored or disposed of as ordinary waste in a security landfill.

2.
Environ Toxicol Chem ; 43(10): 2134-2144, 2024 Oct.
Article in English | MEDLINE | ID: mdl-39092778

ABSTRACT

We compared the effects of lambda-cyhalothrin as the pure active ingredient and as a formulated product (Zero®), on the larval stage of the autochthonous species Boana pulchella. We evaluated ecotoxicological endpoints, behavioral and developmental alterations, and the biochemical detoxifying, neurotoxic, and oxidative stress responses, covering a wide concentration range from environmental to high application levels. Both pyrethroid preparations displayed similar ecotoxicity (median lethal concentration of ~0.5 mg/L), with the lethal effect of Zero® being more pronounced than that of the active ingredient. Sublethal behavioral alterations in natatory activity were observed at 1000 times lower concentrations, indicating the ecological hazard of tadpole exposure to this pyrethroid at environmentally relevant concentrations. Biochemical endpoints in B. pulchella larvae showed significant responses to lambda-cyhalothrin in the ng/L range; these responses were different for the pure or the formulated product, and they were variable at higher concentrations. Principal components analysis confirmed the prevalence of biochemical responses as early endpoints at the lowest lambda-cyhalothrin concentrations; the Integrated Biomarker Response Index proportionally increased with pyrethroid concentration in a similar way for the pure and the formulated products. We conclude that lambda-cyhalothrin is of concern from an environmental perspective, with particular emphasis on autochthonous anuran development. The battery of biochemical biomarkers included in our study showed a consistent integrated biomarker response, indicating that this is a potent tool for monitoring impacts on amphibians. Environ Toxicol Chem 2024;43:2134-2144. © 2024 SETAC.


Subject(s)
Biomarkers , Insecticides , Larva , Nitriles , Pyrethrins , Pyrethrins/toxicity , Animals , Nitriles/toxicity , Larva/drug effects , Insecticides/toxicity , Water Pollutants, Chemical/toxicity , Anura , Oxidative Stress/drug effects
3.
Int J Legal Med ; 138(5): 1977-1983, 2024 Sep.
Article in English | MEDLINE | ID: mdl-38658410

ABSTRACT

The use of less lethal weapons aims to mitigate civilian casualties caused by firearm use. However, due to numerous cases in which these weapons caused serious injuries, even lethal injuries, both legislation and the forensic field are interested in characterizing and regulating them better. In the forensic field, there is a lack of strong research about injury patterns of these weapons which makes it difficult to identify the type of weapon employed. In this study, the main objective was to characterize the injury pattern produced by the impact of the 9 mm P.A.K. projectile. A porcine model was used. Four different distances were studied: firm contact, 10 cm, 60 cm and 110 cm, using 3 of the more representative anatomical sites: the head, the hind leg and the ribs. The average measurement of the entrance orifice varied according to the anatomical site, being 6.67 mm wide and 6.25 mm long in the thorax, 7.3 mm wide and 8.8 mm long in the hind legs, and 7.62 mm wide and 7.54 mm long in the head. The variation in width and length measurements was not found to be directly related to the shot distance. The gunshot residues had similar characteristics to those of conventional lead projectiles, however there was more unburned powder deposit near the wounds, with a less dense soot and more dense powder tattoo. Depth varied widely regardless of tissue and firing distance, although loss of penetrating power and injury is observed as one moves away from the target.


Subject(s)
Forensic Ballistics , Models, Animal , Wounds, Gunshot , Animals , Swine , Forensic Ballistics/methods , Wounds, Gunshot/pathology , Ribs/injuries , Ribs/pathology , Firearms
4.
Rev. Baiana Saúde Pública ; 48(1): 29-45, 20240426.
Article in Portuguese | LILACS | ID: biblio-1555703

ABSTRACT

O Brasil é um país com altas taxas de violência, o que afeta, além da sociedade civil, os agentes das forças da segurança pública, cujas taxas de mortalidade por causas violentas são superiores às da população geral. Portanto, objetivou-se caracterizar o perfil da mortalidade de policiais militares por causas violentas, segundo a cor da pele, no estado da Bahia. Neste estudo, foram analisadas as mortes violentas de policiais militares da ativa ocorridas entre 2012 e 2019, considerando variáveis tanto sociodemográficas quanto relacionadas à corporação policial e às circunstâncias da ocorrência. A análise dos resultados foi realizada por meio da linguagem computacional R versão 4.2.2. Foram registradas 110 mortes de policiais militares, em sua maioria negros (83,64%). Em relação à faixa etária, os policiais militares negros morreram mais jovens, entre 30 e 39 anos (41,30%), enquanto os brancos, entre 40 e 49 anos (61,11%). Em 50% dos casos envolvendo policiais militares negros, a motivação do crime permaneceu desconhecida, enquanto 33,33% das mortes envolvendo policiais brancos foram por confronto com criminosos. Conclui-se que o perfil das mortes de policiais militares no estado da Bahia é semelhante ao da população em geral, com predomínio de homens, negros, jovens e solteiros.


Brazil is a country with high rates of violence, which affects, in addition to civil society, public security agents, whose mortality rates from violent causes are higher than those of the general population. Therefore, the objective was to characterize the profile of mortality of military police officers due to violent causes, according to skin color, in the state of Bahia. This study analyzed violent deaths of active military police officers that occurred between 2012 and 2019, considering both sociodemographic variables and those related to the police force and the circumstances of the occurrence. The analysis of the results was carried out using the computational language R version 4.2.2. A total of 110 military police deaths were recorded, most were black (83.64%). Regarding age group, black military police officers died younger, between 30 and 39 years old (41.30%), whereas white military police officers, between 40 and 49 years old (61.11%). In 50% of cases involving black military police officers, the motivation for the crime remained unknown, whereas 33.33% of deaths involving white police officers were due to confrontation with criminals. In conclusion, the profile of military police deaths in the state of Bahia is similar to that of the general population, with a predominance of male, black, young, and single people.


Brasil tiene altos índices de violencia que no solo afectan a la sociedad civil, sino también a los agentes de seguridad pública, cuyas tasas de mortalidad por causas violentas superan a las de la población general. Así, el objetivo de este estudio fue caracterizar el perfil de mortalidad por causas violentas de los policías militares según el color de la piel, en el estado de Bahía (Brasil). En este estudio se analizaron muertes violentas de policías militares en activo, ocurridas entre 2012 y 2019, considerando variables sociodemográficas relacionadas con el cuerpo policial y las circunstancias de la ocurrencia. El análisis de los resultados se realizó utilizando el lenguaje computacional R, versión 4.2.2. Se registraron 110 muertes de policías militares, la mayoría negros (83,64%). Con relación al grupo de edad, los policías militares negros murieron más jóvenes, de entre 30 y 39 años (41,30%), que los policías militares blancos, de entre 40 y 49 años (61,11%). En el 50% de los casos que involucraron a policías militares negros, la motivación del crimen seguía siendo desconocida, mientras que en el 33,33% de las muertes que involucraron a policías blancos se debieron a enfrentamientos con delincuentes. Se concluye que el perfil de las muertes de policías militares en Bahía es similar al de la población general, con predominio de hombres, negros, jóvenes y solteros.


Subject(s)
Safety , Violence , Cause of Death
5.
Mar Environ Res ; 197: 106465, 2024 May.
Article in English | MEDLINE | ID: mdl-38522121

ABSTRACT

The purpose of this study was to investigate the relationships between the abundance and occurrence of juvenile Atlantic goliath grouper and physicochemical variables in a tropical mangrove ecosystem, employing a non-lethal methodology. Juvenile Atlantic goliath grouper individuals were captured biweekly, using blue crab traps, across three locations within the São Mateus estuary (18°36'S, 39°44'W), from August 2021 to July 2022. Simultaneously, the physicochemical water variables were assessed during each trap inspection. The physicochemical water variables influence on the abundance and occurrence of Atlantic goliath grouper juveniles were assessed using the Zero-Inflated Binomial (ZIB) and the Poisson (ZIP) generalized linear mixed-effects models (GLMMs). A total of 66 Atlantic goliath grouper juveniles were sampled (Pontal do Sul = 50, Lagoa Creek = 13, and Pitangueiras Creek = 3), ranging from 32 to 319 mm in total length. The best model fitted to presence-absence data (AIC = 278.6) consisted of location, depth, and salinity, with only location having a significant influence on the likelihood of species occurrence. Regarding abundance data, the best model (AIC = 336.4) included location, depth, and turbidity, with only location and depth showing a significant impact on abundance variation, with lower abundance at deeper areas. Although our results indicate a weak significant influence of physicochemical variables on juvenile Atlantic goliath grouper distribution, it is imperative to continue this monitoring effort, considering that additional data may be required to gain a deeper understanding of these patterns.


Subject(s)
Bass , Humans , Animals , Ecosystem , Brazil , Seafood , Water
6.
J Econ Entomol ; 117(2): 650-659, 2024 04 12.
Article in English | MEDLINE | ID: mdl-38401129

ABSTRACT

Transgenic insect strains with tetracycline repressible (Tet-Off) female-lethal genes provide significant advantages over traditional sterile insect techniques for insect population control, such as reduced diet and labor costs and more efficient population suppression. Tet-Off systems are suppressed by tetracycline-class antibiotics, most commonly tetracycline (Tc) or doxycycline (Dox), allowing for equal sex ratio colonies of transgenic insects when reared with Tc or Dox and male-only generations in their absence. Dox is a more stable molecule and has increased uptake than Tc, which could be advantageous in some insect mass-rearing systems. Here, we evaluated the suitability of Dox for rearing Tet-Off female-lethal strains of Australian sheep blowfly, Lucilia cuprina (Wiedemann, 1830) (Diptera: Calliphoridae), and New World screwworm, Cochliomyia hominivorax (Coquerel, 1858) (Diptera: Calliphoridae), and the effects of dosage on strain performance. For both species, colonies were able to be maintained with mixed-sex ratios at much lower dosages of Dox than Tc. Biological yields of C. hominivorax on either antibiotic were not significantly different. Reduction of Dox dosages in C. hominivorax diet did not affect biological performance, though rearing with 10 or 25 µg/mL was more productive than 50 µg/mL. Additionally, C. hominivorax mating performance and longevity were equal on all Dox dosages. Overall, Dox was a suitable antibiotic for mass-rearing Tet-Off female-lethal L. cuprina and C. hominivorax and was functional at much lower dosages than Tc.


Subject(s)
Diptera , Animals , Female , Male , Diptera/genetics , Calliphoridae , Doxycycline/pharmacology , Australia , Animals, Genetically Modified , Tetracycline/pharmacology , Anti-Bacterial Agents
7.
Insects ; 15(2)2024 Jan 26.
Article in English | MEDLINE | ID: mdl-38392505

ABSTRACT

The palm leafhopper, Haplaxius crudus, is a possible vector of the pathogen that causes the Lethal Wilt of oil palms in Colombia. This disease represents the biggest phytosanitary problem in the eastern palm zone. From 2010 to 2021, more than 7700 ha have been eradicated, with economic losses exceeding 154 million USD. Therefore, knowing the biology of this insect and its population parameters is necessary for developing population control tools. To evaluate these parameters, a cohort of 100 eggs obtained from H. crudus adults from the breeding unit established in the Campo Experimental Palmar de las Corocoras de Cenipalma in Paratebueno, Cundinamarca, was monitored to record the life cycle and the population parameters using a life table under semi-controlled conditions in an oil palm plantation. The life cycle from egg to adult was 62.7 ± 15.5 days (26.1 ± 2.9 °C; HR: 89.8 ± 14.0%). The egg stage lasted 14.6 ± 0.6 days, the nymphal stage 48.1 ± 2.8 days through five instars, and the adult longevity was 14.8 ± 8.4 days. The specific mortality rate (qx) calculated in the life table was 0.14 (for the egg stage), 0.05 (for I instar), 0.05 (for II instar), 0.03 (for III instar), 0.04 (for IV instar), and 0.07 (for V instar). The population parameters' values were as follows: net reproductive rate Ro = 10.96; generation time T = 62.3 days, intrinsic natural growth rate rm = 0.03, and finite growth rate λ = 1.03. These results help us to understand the population dynamics of this insect in the field and for the development of population control studies.

8.
Mar Pollut Bull ; 200: 116092, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38359479

ABSTRACT

Due to the amply exposure of marine turtles to marine plastic pollution, this is a reason that the green sea turtle Chelonia mydas makes a good candidate species as a bioindicator for plastic pollution. Turtle feces were collected at Isla Blanca on the northeast Caribbean coast of the Yucatan Peninsula, Mexico. Microplastic extraction was done following Hidalgo-Ruz et al. (2012) and Masura et al. (2015) methods. After organic matter degradation of the feces samples, microplastics were identified and quantified by stereomicroscope. Their morphostructure was analyzed by scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy, while their composition was determined by Fourier transform infrared spectroscopy and Raman spectroscopy. Microplastics (MP) abundance ranged from 10 ± 2 MP·g-1 to 89 ± 3 MP·g-1. Kruskal Wallis test (KW = 70.31, p < 0.001) showed a significant difference between 22 green turtles analyzed. Most of the microplastics were fiber type. Blue, purple, and transparent fibers were the most abundant. The identified microplastics were nylon (polyamide), PVC, polypropylene, polyester, and viscose (cellulose). The non-invasive method used here allowed the detection of microplastic pollution and is promising for long-term microplastic pollution monitoring.


Subject(s)
Turtles , Water Pollutants, Chemical , Animals , Microplastics , Plastics/chemistry , Mexico , Water Pollutants, Chemical/analysis , Environmental Monitoring/methods , Caribbean Region , Nylons
9.
Dent Traumatol ; 2023 Nov 23.
Article in English | MEDLINE | ID: mdl-37997492

ABSTRACT

BACKGROUND/AIM: During Chile's period of social unrest, numerous people suffered physical trauma due to the use of police force. However, there have been no reports regarding traumatic dental injuries (TDIs) suffered in this context. This study aims to describe the dental trauma of patients injured by police during the social unrest period in Chile from 2019 to 2021. MATERIAL AND METHODS: A case series methodology was employed. Following informed consent, clinical records of patients admitted to the Ocular and Dentomaxillofacial Prosthetic Care and Rehabilitation Program, who were affected by the violence of state agents during social mobilizations, were reviewed from October 2019 to December 2021. Information on the sociodemographic characteristics of the patients and the TDI diagnoses with their treatment needs were collected. A descriptive analysis was performed. RESULTS: Forty-six patients were identified, nine of whom agreed to the informed consent. Most were male, with a mean age of 28 years, public health insurance, and a high educational level. The most common causes of injury were kinetic impact projectiles (KIPs) and the use of physical force (punches, kicks, or pushes). Of the nine cases described, 26 teeth were affected by TDI. The most affected teeth were the central upper incisors and, in most cases, they presented lesions in both injury categories: NA0D.0 (the tooth and pulp) and NA0D.1 (periodontal tissues). Treatment needs varied and included some complex procedures, such as implant-retained crowns and removable dental prostheses. CONCLUSIONS: The use of force by police during the period of social unrest in Chile caused TDIs among demonstrators, which were mainly due to physical force from less-than-lethal weapons. Most cases presented injuries affecting the incisors with multiple teeth requiring complex treatments.

10.
Toxicon ; 234: 107280, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37673344

ABSTRACT

To corroborate the ontogenetic shift in the venom composition of the Mexican Black-tailed Rattlesnake (Crotalus molossus nigrescens) previously reported through the census approach, we evaluated the shift in the protein profile, lethality, and proteolytic and phospholipase activities of four venom samples obtained in 2015, 2018, 2019, and 2021 from one C. m. nigrescens individual (CMN06) collected in Durango, Mexico. We demonstrated that the venom of C. m. nigrescens changed from a myotoxin-rich venom to a phospholipase A2 and snake venom metalloproteinase-rich venom. Additionally, the proteolytic and phospholipase activities increased with age, but the lethality decreased approximately three times.

11.
Chemosphere ; 341: 140059, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37673183

ABSTRACT

Heavy metals pose a significant threat to animals in aquatic environments due to the adverse effects they exert. Species of the genus Artemia have been described as heavy metal tolerant, but the sensitivity/tolerance range for these species has not been established. In the present study, the toxicity of Cd, Cu, Zn and Ni as reported in the ECOTOX and Web of Science databases was examined for Artemia franciscana and compared with other species and taxonomic groups using an integrative ecotoxicity evaluation. The hazard concentration for 5% of the species (HC5) of acute toxicity tests (24-96 h), obtained through a species sensitivity distribution (SSD) indicated that Cu (0.02 mg/L) and Cd (0.03 mg/L) were the metals with the highest toxicity to aquatic animals followed by Zn (0.15 mg/L) and Ni (0.23 mg/L). In addition to the higher hazard of Cu and Cd to aquatic animals, the comparison of acute LC50 values for A. franciscana indicates lower toxicity of Cd followed by Cu, Zn, and Ni (200.0, 14.5, 9.5, and 0.6 mg/L, respectively). Using the SSD and physiological sensitivity (S) approaches, it was demonstrated that A. franciscana is relatively tolerant to Cd (SSD= HC99; S = 2.21), Cu (SSD= HC97; S = 2.00), Zn (SSD= HC90; S = 1.29) and Ni (SSD= HC83; S = 0.96) compared with other species and taxonomic groups. It appears that tolerance to the metals Cd, Cu, Zn and Ni is unique to the family Artemiidae within the order Anostraca, as the families Streptocephalidae and Thamnocephalidae are not tolerant (have negative S values). Our study confirmed that as expected, A. franciscana presents higher tolerance to Cd, Cu, Zn, and Ni than other aquatic animals. Our findings confirm that A. franciscana can be used as a model organism to understand mechanisms involved in tolerance to heavy metals, mainly Cd and Cu, which are considered highly toxic to other animals.


Subject(s)
Artemia , Metals, Heavy , Animals , Dolphins , Metals, Heavy/toxicity
12.
Insects ; 14(5)2023 Apr 27.
Article in English | MEDLINE | ID: mdl-37233047

ABSTRACT

In Brazil, the citrus fruit borer, Gymnandrosoma aurantianum Lima, 1927, is a serious pest in orange orchards, causing an annual loss of 80 million US dollars, and is managed with multiple insecticide applications, often 56 in a single season. On the other hand, the parasitoid wasp Trichogramma atopovirilia Oatman & Platner, 1983 has the potential for controlling G. aurantianum by attacking its eggs. Considering the intensive insecticide applications in citrus orchards in Brazil to control the large complex of pests, especially Diaphorina citri Kuwayama, 1908, evaluation of the harmful effects of insecticides on T. atopovirilia is important to maximize efficiency in managing G. aurantianum. Here, we tested the effects of new products used in citrus orchards (cyantraniliprole, cyantraniliprole + abamectin, abamectin, sulfoxaflor, spinetoram, flupyradifure, and Cordyceps fumosorosea (Wize) Kepler, B. Shrestha & Spatafora) on adults and pupae of T. atopovirilia. Of the insecticides tested, spinetoram caused the highest impacts on T. atopovirilia parasitism, longevity, emergence, and mortality. The other products caused more sublethal than lethal effects and were classified as 1 and/or 2 in the IOBC/WPRS classification. Abamectin, cyantraniliprole, cyantraniliprole + abamectin, and the entomopathogenic fungus C. fumosorosea were classified as short-lived. Except for spinetoram, these products were classified as selective. In this study, spinetoram was considered harmful to T. atopovirilia and, therefore, should be managed carefully in IPM programs combining this parasitoid. In order to safely use this insecticide, one should respect the interval of release of the parasitoid, which is 21 days after its spraying. The novel products tested, cyantraniliprole, cyantraniliprole + abamectin, abamectin, sulfoxaflor, and the entomopathogenic fungi C. fumosorosea were selective and non-persistent to T. atopovirilia. These products are possible replacements for non-selective insecticides to achieve higher control from both chemical and biological tools.

13.
J Appl Toxicol ; 43(9): 1393-1405, 2023 09.
Article in English | MEDLINE | ID: mdl-37055923

ABSTRACT

Produced water (PW) generated by oil companies is a highly impacting waste that contains chemicals such as metals and organic and inorganic compounds. Given its polluting potential, PW requires effective treatment before being discharged into the environment. Conventional treatments have limited efficiency in removing PW toxicity, so alternative approaches must be developed and standardized. In this context, treatment with adsorbent materials like magnetized vermiculite (VMT-mag) is highlighted. This work aimed to evaluate the efficiency of treatment with VMT-mag in reducing PW toxicity to aquatic biota. For this purpose, three aquatic species (the midge Chironomus riparius, the planarian Girardia tigrina, and the crustacean Daphnia magna) were exposed to untreated PW and to PW treated with VMT-mag at laboratory conditions. The assessed endpoints included mortality, growth, emergence, and developmental time of C. riparius; mortality, locomotion, feeding, and head regeneration of G. tigrina; and intrinsic population growth rate (r) and reproductive output of D. magna. The results showed that all the species exposed to raw PW were impaired: C. riparius had delayed development, G. tigrina had reduced locomotor activity and delayed head regeneration, and D. magna had reduced reproduction and delayed intrinsic population growth rate (r). Most of the analyzed parameters showed that treatment with VMT-mag diminished PW toxicity. Therefore, using VMT-mag to treat PW may be the key to reducing the PW effects on aquatic organisms.


Subject(s)
Aluminum Silicates , Oil and Gas Industry , Waste Disposal, Fluid , Wastewater , Water Pollutants, Chemical , Animals , Aluminum Silicates/chemistry , Aquatic Organisms , Daphnia , Water/chemistry , Water Pollutants, Chemical/chemistry , Water Pollutants, Chemical/toxicity , Wastewater/chemistry , Waste Disposal, Fluid/methods , Toxicity Tests
14.
Acta biol. colomb ; 28(1): 57-63, ene.-abr. 2023. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1573597

ABSTRACT

ABSTRACT This study evaluated the sensitivity of male and female of guppies (Poecilia reticulata) to ammonia. LC50-96h for males, females and combined sexes of P. reticulata was 37.33, 48.34, and 42.45 mg/L of total ammonia or 1.03, 1.34, and 1.17 mg/L of un-ionized ammonia. The mortality at the concentration of 40 mg/L of total ammonia differed between the sexes with higher mortality in males. These results have implications for production systems, since recommendations of ammonia toxicity reference values that do not consider the difference between the sexes, can lead to the mortality of males, and cause economic losses because males have higher commercial value in the ornamental market.


RESUMEN Este estudio evaluó la sensibilidad de machos y hembras de guppies (Poecilia reticulata) al amoníaco. La CL50-96h para machos, hembras y sexos combinados de P. reticulata fue de 37,33; 48,34 y 42,45 mg/L de amoníaco total o 1,03; 1,34 y 1,17 mg/L de amoníaco no ionizado. La mortalidad a la concentración de 40 mg/L de amoníaco total difirió entre los sexos con mayor mortalidad de los machos. Estos resultados tienen implicaciones para los sistemas de producción, una vez que las recomendaciones de valores de referencia de toxicidad del amoníaco que no consideren la diferencia entre sexos, pueden conducir a la mortalidad de los machos y provocar pérdidas económicas, debido a que los machos tienen mayor valor comercial en el mercado ornamental.

15.
Rev. cuba. med. mil ; 52(1)mar. 2023.
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1521985

ABSTRACT

Introducción: El linfoma de células T citotóxico/natural killer extranodal de tipo nasal es poco frecuente, pero con alta tasa de mortalidad. Las manifestaciones clínicas de la enfermedad pueden simular una infección de senos paranasales. Objetivo: Presentar las manifestaciones clínicas de un paciente de 34 años de edad con diagnóstico de linfoma de células T citotóxico/natural killer extranodal de tipo nasal. Caso clínico: Se presenta un paciente masculino de 34 años de edad con rinorrea verdosa fétida recurrente y obstrucción en fosa nasal derecha. En la evaluación inicial sugiere sinusitis crónica, sin embargo, debido al empeoramiento de las manifestaciones clínicas se realiza una tomografía computarizada que muestra lesiones sugestivas de infiltración neoplásica, una biopsia de la lesión confirma el diagnóstico de linfoma de células T/natural killer extranodal de tipo nasal. Conclusiones: Los linfomas de células T citotóxico/natural killer extranodal de tipo nasal son considerados neoplasias poco frecuentes, caracterizadas por el patrón rápidamente progresivo con afectación ósea; en su etapa inicial presenta manifestaciones clínicas similares a una sinusitis. La tomografía computarizada y la histopatología, son indispensables en el diagnóstico de la enfermedad.


Introduction: Nasal-type extranodal natural killer/cytotoxic T-cell lymphoma is rare but has a high mortality rate. The clinical manifestations of the disease can mimic a paranasal sinus infection. Objective: To present the clinical manifestations of a 34-year-old patient diagnosed with nasal-type extranodal natural killer/cytotoxic T-cell lymphoma. Clinical case: A 34-year-old male patient with recurrent greenish fetid rhinorrhea and obstruction in the right nostril is presented. In the initial evaluation, it suggests chronic sinusitis, however, due to the worsening of the clinical manifestations, a computed tomography is performed that shows lesions suggestive of neoplastic infiltration, a biopsy of the lesion confirms the diagnosis of T-cell lymphoma/extranodal natural killer. Conclusions: Nasal-type extranodal natural killer/cytotoxic T-cell lymphomas are considered rare neoplasms characterized by a rapidly progressive pattern with bone involvement; in its initial stage it presents clinical manifestations similar to sinusitis. Computed tomography and histopathology are essential in the diagnosis of the disease.

16.
Pest Manag Sci ; 79(4): 1316-1323, 2023 Apr.
Article in English | MEDLINE | ID: mdl-36411496

ABSTRACT

BACKGROUND: Eriopis connexa is an important predator in the Neotropical region, associated with pests of economic relevance on horticultural crops in Argentina. The use of broad-spectrum insecticides could reduce the biodiversity of these natural enemies in agroecosystems and put at risk its conservation. New, selective "risk reduced" insecticides could be an alternative to conventional chemical control to promote sustainable agriculture. The goal of this work was to assess the lethal and sublethal effects of two insect growth regulator (IGR) insecticides on eggs and two larval instars of E. connexa exposed to insecticides. RESULTS: Pyriproxyfen and cypermethrin significantly affected egg hatching by 28.8% and 70.4%, respectively. Pyriproxyfen reduced the survival of larvae that emerged by ≈52% from Day (D3)3 after hatching and caused the lengthening of developmental time for both larval and pupal stages. By contrast, teflubenzuron did not reduce hatching and survival but shortened the developmental time of the pupae stage. Cypermethrin reduced the survival of 2nd (L2 ) and 4th (L4 ) larval instars by 36.4% and 74.6%, respectively, and lengthened the development time of L2 . Pyriproxyfen lengthened the development time of L4 and reduced the fecundity and fertility of females. Teflubenzuron reduced survival of L2 and L4 larval instars by 46.9% and 28.6%, respectively, and lengthened the total development time for the larval stage. In addition, teflubenzuron reduced the fecundity and fertility of females. CONCLUSIONS: Both eggs and larvae were susceptible to exposure to IGR, showing lethal and sublethal effects. This study highlights, once again, the higher toxicity of cypermethrin to E. connexa. The toxicity of both IGR insecticides could impair the performance of E. connexa as a biological control agent in agroecosystems. © 2022 Society of Chemical Industry.


Subject(s)
Coleoptera , Insecticides , Animals , Female , Insecticides/pharmacology , Larva , Juvenile Hormones/pharmacology
17.
Braz. j. biol ; 83: e272853, 2023. tab, graf, ilus
Article in English | VETINDEX | ID: biblio-1505867

ABSTRACT

The aim of this study was to determine the acute toxicity of the essential oils (EOs) of Aloysia triphylla, Lippia gracilis and Piper aduncum in juvenile tambaqui (Colossoma macropomum), and evaluate the possible histopathological alterations in their gills. For the acute toxicity tests, juvenile tambaqui (n=24/treatment) were distributed in six treatments with three replicates, which comprised the control and five EO concentrations of A. triphylla (60, 80, 100, 120 and 140 mg L-1), L. gracilis (35, 40, 45, 50 and 55 mg L-1) and P. aduncum (42.5, 45, 47.5, 50 and 52.5 mg L-1), with an exposure period of 4 h. The mortality rate and severity of damage to the tambaqui gills were proportional to the increase in the concentration of the EO, with LC50-4 h values estimated at 109.57 mg L -1 for A. triphylla, 41.63 mg L -1 for L. gracilis and 48.17 mg L -1 for P. aduncum. The main morphological damages observed in the gills of the tambaqui exposed to the three EOs, were Grade I: hypertrophy and hyperplasia of lamellar epithelial cells, lamellar fusion, epithelial detachment, capillary dilation and constriction, proliferation of chloride cells and mucosal cells and edema; in low frequency Grade II damage as epithelial rupture and lamellar aneurysm. Necrosis (Grade III damage) was observed only in gill lamellae exposed to P. aduncum EO (47.5, 50.0 and 52.5 mg L-1). Concentrations of EOs below LC50-4 h can be used sparingly, for short periods of exposure for the treatment of diseases in tambaqui breeding.


O objetivo deste estudo foi determinar a toxicidade aguda dos óleos essenciais (OEs) de Aloysia triphylla, Lippia gracilis e Piper aduncum em juvenis de tambaqui (Colossoma macropomum), e avaliar as possíveis alterações histopatológicas em suas brânquias. Para os testes de toxicidade aguda, juvenis de tambaqui (n=24/tratamento) foram distribuídos em 6 tratamentos, com três repetições, sendo o controle e cinco concentração do OE de A. triphylla (60, 80, 100, 120 e 140 mg L-1), L. gracilis (35, 40, 45, 50 e 55 mg L-1) e P. aduncum (42,5, 45, 47,5, 50 e 52,5 mg L-1), com exposição de 4 h. A taxa de mortalidade e a severidade dos danos nas brânquias de tambaqui foram proporcionais ao aumento da concentração do OE, com os valores de CL50-4 h estimados em 109,57 mg L-1 para A. triphylla, em 41,63 mg L-1 para L. gracilis e em 48,17 mg L-1 para P. aduncum. Os principais danos morfológicos observados nas brânquias de tambaqui, expostos aos três OEs, foram os de grau I: hipertrofia e hiperplasia das células do epitélio lamelar, fusão lamelar, descolamento epitelial, dilatação e constrição capilar, proliferação de células de cloreto e de células mucosas e edema; em baixa frequência os de grau II como ruptura epitelial e aneurisma lamelar. Necrose (dano de grau III) foi observado somente nas lamelas branquiais expostas ao OE de P. aduncum (47,5, 50,0 e 52,5 mg L-1). Concentrações do OEs abaixo dos valores de CL50-4 h podem ser utilizados com parcimônia, em curtos períodos de exposição para o tratamento de doenças na criação de tambaqui.


Subject(s)
Animals , Oils, Volatile/toxicity , Piper/toxicity , Lippia/toxicity , Fisheries , Fishes
18.
Toxicol Rep ; 9: 210-218, 2022.
Article in English | MEDLINE | ID: mdl-36518451

ABSTRACT

Emerging contaminants such as sunscreens, hair dyes and flame retardants have been found at important concentrations in surface water (river, lake, ocean), but their negative impact on different aquatic species is not fully known. This study evaluated the effect of benzophenone (BZ), 2,5-diaminotoluene sulfate (PTD), p-phenylenediamine (PPD) and tetrabromobisphenol A (TBPA) on survival (LC50) and the impact of sublethal concentrations (LC25) on the activity of enzymes linked to stress oxidative process in brine shrimp under two temperature conditions (22 °C and 28 °C) for 24 h and 48 h of exposure time. LC50 values obtained for each chemical substance and the activity of GST, AChE and LDH were significantly affected by the temperature conditions and exposure time. In contrast, GPx was only altered by the tested compound. TBBPA (LC50 from 17.05 up to 28.55 µg/L) and BZ (LC50 from 14.86 up to 24.49 mg/L) resulted in the most toxic substances for A. salina. The impact of dyes, such as PTD and PPD, on aquatic organisms is limited. These are the first results that show that not only dyes, but their respective by-products induce harmful effects in brine shrimp (LC50 for PTD and PPD were 23.6-396.3 and 52.0-164.9 mg/L respectively). Although this study model was very useful to evaluate the ecotoxicity of the different ECs, additional research is needed to increase available information related to the effects of dyes and other non-studied micropollutants on aquatic systems in general.

19.
Neotrop Entomol ; 51(6): 869-876, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36214967

ABSTRACT

The first step for biological insecticide production is the evaluating of the pathogenicity and strains virulence of entomopathogens against the target pests. Bacillus thuringiensis (Bt) is widespread in nature, lethal pathogen of a range of orders and the most widely used entomopathogenic biological control agent. Therefore, our objective was to study the susceptibility of six important lepidopteran pests in Brazilian agricultural production systems, Anticarsia gemmatalis (Hübner), Chrysodeixis includens (Walker) Helicoverpa armigera (Hübner), Spodoptera cosmioides (Walker), S. eridania (Cramer), and S. frugiperda (Smith), to Bt strains. In vitro bioassays were conducted with neonate larvae exposed to two Bt strains, 1680A and 775E, in seven concentrations of spores and protein crystals. After 7 days, the mortality was evaluated and indicated that lethal concentration (LC50) for 775E strain ranged from 7.72 × 104 to 2.45 × 106 spores mL-1 and for 1608A strain from 5.63 × 103 to 1.21 × 106 spores mL-1. The strain 1608A was more toxic for A. gemmatalis and H. armigera than 775E strain, and then was further evaluated in greenhouse bioassays with maize and soybean plants infested separately with target insects. The strain 1608A showed an efficient control for most insect species studied in the greenhouse bioassays, promoting considerable reduction in leaf injury and demonstrating a high potential in biological control of important lepidopteran species in crop production systems in Brazil.


Subject(s)
Bacillus thuringiensis , Moths , Animals , Bacillus thuringiensis/genetics , Bacillus thuringiensis Toxins , Hemolysin Proteins/genetics , Endotoxins , Brazil , Bacterial Proteins/genetics , Larva , Insecta , Pest Control, Biological , Plants, Genetically Modified
20.
Plant Dis ; 2022 Oct 20.
Article in English | MEDLINE | ID: mdl-36265144

ABSTRACT

Lethal Yellowing (LY) disease causes major damage to palms in Central America and the Caribbean. It has been reported as far south as Antigua (Myrie et al., 2014). LY affects over forty palm species, seriously impacts the coconut industry and alters the landscapes on islands with a tourist-based economy. In March 2021, the presence of LY disease was regularly monitored in Guadeloupe. Two palm species (Cocos nucifera and Pritchardia sp.) died on a private property in Saint-Anne, Grande Terre. Yellowing of lower fronds and necrosis of inflorescences were reported on some neighboring palms. One symptomatic Cocos nucifera (GP21-007) and four symptomatic Pritchardia sp. (GP21-005, GP21-006, GP21-008 and GP21-009) were sampled by stem drilling. Samples from four asymptomatic coconut trees (GP21-001 to GP21-004) were collected in the locality of Deshaies. DNA was extracted from the nine sawdust samples following a cetyltrimethylammonium bromide (CTAB) modified protocol (Doyle and Doyle, 1990). A quantitative polymerase chain reaction (PCR), following the protocol described by Christensen et al. (2004), was performed on DNA to diagnose the presence of phytoplasmas. An exponential amplification was observed for all DNA extracts from symptomatic palm samples (threshold number of PCR cycles (Ct) ranged from 18.50 to 23.58). DNA from asymptomatic samples yielded negative results (undetermined Ct). To identify the phytoplasma associated with LY, DNA samples were subjected to PCR, based on the 16SrRNA gene, plus internal transcribed spacers (ITS) using P1-1T (Pilet et al., 2021)/P7 (Schneider et al., 1995) primers, and secA gene using the primer pair secAFor1/secARev1 (Hodgetts et al. 2008). Amplicons of 1.8 kb covering the 16S ribosomal operon and 830 bp for the secA gene were produced using DNA from symptomatic trees. All amplicons were double strand sequenced (Genewiz, UK). The corresponding sequences were deposited in GenBank and subjected to BLASTn on NCBI. Sequences of the ribosomal operon gene (accession no. ON521114 to ON521118) were identical for the five positive samples. Sequencing revealed two distinct ribosomal operons with heterozygous peaks on the DNA chromatogram. The first aMino ambiguity (M = Adenine or Cytosine) was observed in the 16Sr RNA gene. The second was observed in the first intergenic transcript spacer. The 16S rDNA sequence (M = Cytosine) presented 100% identity with accession no. HQ613874 and 99.93% with accession no. U18747, the reference sequence for 'Candidatus Phytoplasma palmae'. The virtual RFLP pattern derived from the 16S rDNA F2nR2 fragment and identified using iPhyclassifier (Zhao et al. 2009) was identical to the reference pattern for the 16SrIV-A subgroup. A unique sequence was obtained for the partial secA gene (OP136139 to OP136143), sharing 100% identity with EU267187 for the palm LY phytoplasma preprotein translocase subunit (secA) gene. This is the first report of 'Ca. Phytoplasma palmae' (subgroup 16SrIV-A) associated with palm LY disease on Cocos nucifera and Pritchardia sp. in Guadeloupe. Measures to eradicate LY were implemented as soon as its presence was confirmed in Guadeloupe. LY phytoplasmas continue to spread in the Caribbean and are approaching South America, where the known vector, Haplaxius crudus, has already been reported (Silva et al., 2019). This poses a major threat to the coconut economy and the diversity of palm trees.

SELECTION OF CITATIONS
SEARCH DETAIL