Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 10 de 10
Filtrar
1.
Environ Sci Pollut Res Int ; 31(19): 28827-28834, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38587780

RESUMO

Numerous chemical compounds are found in aquatic environments; among them are pesticides. Pesticides are widely used worldwide, and this use has progressively increased in recent decades, resulting in the accumulation of potentially toxic compounds in surface waters. Dimethylamine-based herbicides (DBH) and imidacloprid-based insecticides (IBI) have low soil absorption and high water solubility, facilitating the arrival of these compounds in aquatic environments. In this study, our objective was to analyze whether two pesticides, DBH and IBI at environmentally relevant concentrations of 320 µg/L for each compound, and their mixtures impact the behavioral and endocrine parameters of adult zebrafish, verifying the effect of pesticides on exploratory behavior and social and analyzing hormonal parameters related to stress. Acute exposure to the mixture of pesticides reduced fish locomotion. Pesticides alone and in combination did not affect cortisol levels in exposed animals. Pesticides, when tested together, can cause different effects on non-target organisms, and the evaluation of mixtures of these compounds is extremely important.


Assuntos
Locomoção , Neonicotinoides , Nitrocompostos , Praguicidas , Peixe-Zebra , Animais , Peixe-Zebra/fisiologia , Neonicotinoides/toxicidade , Locomoção/efeitos dos fármacos , Praguicidas/toxicidade , Nitrocompostos/toxicidade , Dimetilaminas , Poluentes Químicos da Água/toxicidade
2.
Artigo em Inglês | MEDLINE | ID: mdl-36167257

RESUMO

The endocrine disruptors (ED), even in low concentration, can change the homeostasis of an organism through the biochemical and physiological pathways; and are gaining more relevance due to their well-reported presence in the natural environment. EDs mainly affect non-target animals, which can bioaccumulate, leading to changes in metabolism. Another problem is due to several organisms that compose the aquatic biota serving as a basis of the food chain and transferring it to higher trophic levels. Here we evaluated the dietary transference of 17α-ethinylestradiol (EE2), in adult zebrafish chronically fed by EE2-bioaccumulated brine shrimp (BS). For this, we evaluated behavioral biomarkers such as the novel tank test (NTT), social preference test (SPT), mirror-induced aggressivity (MIA), and biochemical biomarkers such as acetylcholinesterase (AChE), superoxide dismutase (SOD), catalase (CTL), and glutathione-S-transferase (GST) activity, cortisol, and lipid peroxidation levels in adult zebrafish. The behavioral effects can be explained by the changed effects on acetylcholinesterase activity as well as in the antioxidant system mainly affected by the high levels of EE2 identified by HPLC shown that had occurred during a dietary transfer for fish. EE2 has a potential pattern for bioaccumulation and dietary transfer in biological tissue and EE2 can affect the behavior of fish. The observed effects could be dangerous to the environment, affecting, other animals and even human health.


Assuntos
Disruptores Endócrinos , Poluentes Químicos da Água , Acetilcolinesterase/metabolismo , Animais , Antioxidantes/metabolismo , Biomarcadores/metabolismo , Catalase/metabolismo , Disruptores Endócrinos/metabolismo , Disruptores Endócrinos/toxicidade , Etinilestradiol/metabolismo , Etinilestradiol/toxicidade , Glutationa/metabolismo , Humanos , Hidrocortisona/metabolismo , Superóxido Dismutase/metabolismo , Transferases/metabolismo , Poluentes Químicos da Água/metabolismo , Peixe-Zebra/metabolismo
3.
Contemp Clin Trials Commun ; 26: 100903, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35243124

RESUMO

Cervical cancer is the leading cause of cancer mortality among Malawian women, despite being preventable through screening and preventive therapy. In 2004, Malawi implemented a national screening program, using visual inspection with acetic acid (VIA) and cryotherapy, but its success has been limited due to equipment and human resources challenges. Since the development of that program, new technologies for screening and treatment that are less resource-intensive and more scalable have become available. GeneXpert systems provide fast, accurate HPV results and are increasingly available in low-income countries. Self-collection for human papillomavirus (HPV) testing is a validated method for screening and improves uptake. Thermal ablation provides an alternative ablative treatment that is simpler to use than cryotherapy and can be performed with portable devices. Meanwhile, urine HPV testing methods provide promising options for primary screening. We designed a single-arm prospective study to investigate a novel HPV screen-triage-treat strategy among 1250 women in Lilongwe, Malawi. Our proposed strategy consists of (1) Xpert HPV testing of self-collected samples, (2) VIA and colposcopy for HPV-positive women, and (3) thermal ablation for HPV-positive/ablation-eligible women. We will collect cervical biopsies, Pap smears, and endocervical samples to validate the HPV results and VIA/colposcopy findings against endpoints of high-grade cervical intraepithelial neoplasia or cancer (CIN2+). We will evaluate same-day completion of our algorithm, its performance in triaging women for treatment, and 24-week treatment efficacy of thermal ablation. We will also explore the performance of HPV and methylation tests in urine samples, as compared to provider- and self-collected cervicovaginal samples.

4.
Artigo em Inglês | MEDLINE | ID: mdl-35292329

RESUMO

Pesticides reach water bodies through different routes, either owing to incorrect packaging disposal, direct application to control macrophytes, leaching from fields, or natural degradation processes. In the aquatic environment, adverse effects in non-target species that come in contact with these substances are poorly understood. Currently, the most used pesticides are glyphosate (GBH) and 2,4-dichlorophenoxyacetic acid-based herbicides (DBH), as its presence in water bodies is already known, we used environmental concentrations and our exposure time comprised the entire period of organogenesis (3-120 h post-fertilization). We evaluated the response of embryos in their early development with the parameters of mortality, hatching, spontaneous movement, and heart rate; and it's through behavior the open field test and aversive stimulus, as well as biochemical analyzes of acetylcholinesterase activity (AChE), catalase (CTL) and superoxide dismutase (SOD) as a possible mechanism of action. Exposure to GBH decreased survival, caused hypermobility and anxiolytic behavior, negatively affected the anti-predatory behavior of the larvae, and increases acetylcholinesterase activity, whereas exposure to DBH caused only slight hypermobility in the larvae and increases acetylcholinesterase activity. These changes may compromise the perpetuation of the species, the search for partners/food, and facilitate the action of predators, which can result in serious ecological consequences.


Assuntos
Herbicidas , Praguicidas , Poluentes Químicos da Água , Acetilcolinesterase/metabolismo , Animais , Herbicidas/toxicidade , Larva , Praguicidas/toxicidade , Água , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/metabolismo
5.
Int J Cancer ; 149(2): 371-377, 2021 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-33687746

RESUMO

Malawi has the highest invasive cervical cancer (ICC) mortality rate worldwide, and ICC is the leading cause of cancer death among women. In 2004, Malawi adopted visual inspection with acetic acid (VIA) and ablative treatment with cryotherapy. However, screening coverage has remained low (<30%) and few women (<50%) who require ablative treatment receive it. Additional barriers include long distances to health facilities and challenges with maintaining gas supplies. Thermal ablation is a safe and effective alternative to cryotherapy. We assessed the safety and uptake of community-based ICC screening with VIA and same-day treatment using a handheld thermocoagulator (HTU) in rural Malawi. We held educational talks alongside community leaders and conducted VIA screening in nonclinic community settings to nonpregnant women aged 25 to 49 years without history of hysterectomy or genital cancer/precancer. Eligible women received same-day thermal ablation and HIV testing/counseling. We collected cervical biopsies before treatment and followed up women at Weeks 6 and 12, with repeat biopsy at Week 12. Between July and August 2017, 408 (88%) of 463 eligible women underwent VIA. Overall, 7% (n = 30) of women had a positive VIA, of whom 93% (n = 28) underwent same-day thermal ablation. Among the 30 VIA-positive women, 5 had cervical intraepithelial neoplasia (CIN) 1, 4 had CIN 2/3 and 21 had benign histologic findings. Abnormal vaginal discharge (60%) and light vaginal bleeding (52%) were the most reported adverse events. There was high uptake of the community-based ICC screening in the study population and treatment was safe in this setting. Similar strategies that minimize false-positive results are urgently needed in Malawi.


Assuntos
Ácido Acético/administração & dosagem , Hipertermia Induzida/métodos , Displasia do Colo do Útero/terapia , Neoplasias do Colo do Útero/terapia , Adulto , Detecção Precoce de Câncer , Feminino , Humanos , Hipertermia Induzida/efeitos adversos , Malaui , Programas de Rastreamento , Pessoa de Meia-Idade , População Rural
6.
Acta biol. colomb ; 21(2): 399-412, mai.-ago. 2016. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-781907

RESUMO

Se determinaron los cambios en composición, densidad y distribución espacial de la edafofauna de hojarasca entre dos usos de suelo (cafetal y bosque subandino) para entender el efecto del uso de suelo. Asimismo, se establecieron las relaciones entre las variables de la edafofauna y atributos de la hojarasca. Se colectaron muestras de hojarasca superficial durante la época seca y se extrajo la edafofauna, manualmente y mediante embudos Berlese modificados. Esta se identificó hasta el menor nivel taxonómico posible y se clasificó en grupos funcionales. La composición faunística fue diferente entre los usos de suelo. La similitud en la composición fue menor al 50 % en dos de los tres grupos funcionales encontrados, pero la densidad total no presentó diferencias. En general hubo coeficientes de variación altos en la densidad faunística intermuestral para los diferentes grupos taxonómicos y, en consecuencia, una baja detectabilidad del patrón espacial. Sin embargo, se detectó un patrón espacial en la abundancia para Coleoptera, larvas de Diptera y biomasa de hojarasca, en el cafetal. La estructura fue más difícil de detectar en bosque, por los pequeños parches en este. La varianza de la abundancia fue mayor en el cafetal, para todos los grupos, excepto Acaridida y Formicidae. La densidad de Formicidae aumentó al hacerlo la humedad de la hojarasca, pero solo en cafetal. Se concluye que el establecimiento del cafetal afecta de manera diferencial a taxones y grupos funcionales de la edafofauna. Esto sienta las bases para definir los efectos del cambio de uso de suelo y los factores ambientales asociados con la distribución espacial de la edafofauna.


Changes in composition, density and spatial distribution on the litter edaphic fauna between two land uses (a coffee plantation and a tropical Andean forest) were established, in order to understand the soil use effects. Also, the relationships between the biotic variables and some litter features were evaluated. Superficial litter samples were collected during dry season. The edaphic fauna was extracted manually and with modified Berlese funnels; it was identified up to the lower taxonomic level and classified in functional groups. Differences in fauna composition were observed between the two land uses. Composition similarity was lower than 50 % for almost all functional groups found, but total density did not differ between the land uses. In general, there was a high variation in density among samples resulting in higher coefficients of variation for different taxonomic groups and consequently low detectability of spatial pattern. However a spatial pattern was detected only for Coleoptera, Diptera larvae and litter biomass in the coffee plantation. The structure in forest was more difficult to detect, due to the smaller patches on it. The variance of abundance was significantly higher in the coffee plantation for all groups, except Acaridida and Formicidae. Density of Formicidae increased with the enhancement of litter moisture, but only in the coffee plantation. In conclusion, the establishment of coffee plantation differentially affects taxa and functional groups of soil fauna. This is the basis for establishing the effects of soil change use, and the environmental factors associated with spatial distribution of edaphic fauna.

9.
Rev. colomb. obstet. ginecol ; 46(1): 33-40, ene.-mar. 1995. tab
Artigo em Espanhol | LILACS | ID: lil-293085

RESUMO

249 sueros de pacientes con diagnóstico de Carcinoma cervical (CA INV), Neoplasia Intraepitelial Cervical (NIC) y de mujeres sanas fueron analizados mediante la técnica de ELISA empleando 14 icosapéptidos sintéticos sobrelapados que representan la secuencia de aminoácidos de la proteína E7 del virus del papiloma tipo 16 (E7-VPH 16).Las principales regiones de la proteína reconocidas por las pacientes con diagnóstico de CA: invasivo fueron representadas por los péptidos E7 (1-20) (11.3 por ciento) y E7 (66-85 ) (12.5 por ciento) Ninguno de los controles mostró reactividad hacia estos péptidos. Para confirmar esta reactividad, los sueros fueron analizados mediante inmunotransferencia con proteína E7-VPH 16 recombinante; 28.2 por ciento de los sueros del grupo de CA invasivo fueron positivos, ningún suero del grupo control reconoció la proteína recombinante. Las reactividades de sueros de pacientes y controles hacia péptidos diferentes de E7 (11-30) y E7 (66-85) no fueron confirmados. La detección de anticuerpos hacia estos dos péptidos podría ser útil en el seguimiento de las pacientes con CA de cérvix


Assuntos
Humanos , Feminino , Adulto , Papiloma/complicações , Papiloma/etiologia , Papiloma/prevenção & controle , Papiloma/terapia , Papiloma/virologia
10.
Arch. argent. pediatr ; 83(3): 150-5, 1985. tab, ilus
Artigo em Espanhol | LILACS | ID: lil-26375

RESUMO

Entre enero de 1978 y diciembre de 1983 fueron asistidos 108 niños por ingestión de sustancias cáusticas. Sólo 86 completaron su seguimiento hasta el alta. En la mitad de los casos el tóxico ingerido fue hidróxido de sodio (soda cáustica). La distribución por edades mostró una mediana de 24 meses. A todos los pacientes se les indicó el mismo esquema de tratamiento. La radiografia contratada de esófago realizada entre el 7- y el 30- día mostró ser pronóstica de las lesiones severas. Se realizó endoscopia esofágica a 31 pacientes durante los primeros días de evolución; 17 tuvieron lesiones de la mucosa esofágica que en 2 de ellos fueron severas y coincidieron con la evolución a la estenosis. Hubo correlación endoscópica/radiológica. Se consideraron pacientes de alto riesgo con probabilidad de desarrolar estenosis, aquellos niños que con el antecedente de ingesta de álcali presenten: a) Retraso mental. b) Lesiones intensas de orofaringe. c) Disfagia inicial que persiste más de 48 horas. Consideramos que la conducta ante todo niño que haya ingerido ese cáustico es: 1) Tratamiento con corticoides durante 15 días. 2) Radiografía contrastada de esófago entre el 7§ y el 10§ día. Si ésta presenta anormalidad, efectuar esofagoscopia y eventual dilatación


Assuntos
Queimaduras Químicas , Cáusticos/efeitos adversos , Esôfago/lesões , Estenose Esofágica/induzido quimicamente , Corticosteroides/uso terapêutico , Estenose Esofágica/tratamento farmacológico
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA