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1.
Braz. j. biol ; 842024.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469388

RESUMO

Abstract The active ingredient glyphosate is the most commercialized herbicide on the world market due to its capability in eliminating weeds. However, it can harm the development of non-target organisms and threaten environmental quality. This study analyzed the effects of potentially toxic concentrations of glyphosate on germination, growth, cell cycle and genomic stability of Lactuca sativa L., and identified the most sensitive variables for assessing the toxicity of this herbicide to this biomonitor. Seeds of L. sativa were germinated in Petri dishes containing a sheet of filter paper moistened with 5 mL of a concentration of glyphosate (1.34, 3.35, 6.70, 10.05, 13.40 mg L-1). Controls consisted of distilled water (negative) and 3 mg L-1 CuSO4 (positive). Macroscopic and microscopic variables were analyzed. The germination of L. sativa was not affected by the concentrations of glyphosate. Root length and shoot height of the plants and the mitotic index decreased from the lowest concentration tested on. The chromosomal anomaly index and frequency of micronuclei increased by 3.2 and 22 times, respectively, with the presence of the lowest concentration of glyphosate compared to the negative control. The observed phytotoxic and cytogenotoxic effects demonstrate the negative influence that glyphosate has on the development of L. sativa. Root length and microscopic variables showed the highest sensitivity. This study warns of the possible harmful effects that glyphosate can have on non-target organisms and suggests greater control over the use of this herbicide to mitigate its environmental impact.


Resumo O ingrediente ativo glifosato é o herbicida mais comercializado do mercado mundial, pela sua capacidade de eliminar as plantas daninhas. No entanto, ele pode prejudicar o desenvolvimento dos organismos não-alvo e ameaçar a qualidade do ambiente. O estudo teve como objetivo analisar os efeitos de concentrações potencialmente tóxicas de glifosato sobre a germinação, o crescimento, o ciclo celular e a estabilidade genômica de Lactuca sativa L., e identificar as variáveis mais sensíveis para avaliar a toxicidade deste herbicida ao biomonitor. Sementes de L. sativa foram germinadas em placas de Petri contendo uma folha de papel-filtro umedecida com 5 mL das concentrações de glifosato (1,34, 3,35, 6,70, 10,05, 13,40 mg L-1). Os controles consistiram em água destilada (negativo) e 3 mg L-1 de CuSO4 (positivo). Variáveis macroscópicas e microscópicas foram analisadas. A germinação de L. sativa não foi afetada pelas concentrações de glifosato. O comprimento da raiz e a altura da parte aérea das plantas e o índice mitótico reduziram desde a menor concentração testada. O índice de anomalias cromossômicas e a frequência de micronúcleos aumentaram, respectivamente, 3,2 e 22 vezes na presença da menor concentração de glifosato em comparação ao controle negativo. Os efeitos fitotóxicos e citogenotóxicos observados demonstram a interferência negativa do herbicida no desenvolvimento de L. sativa. O comprimento da raiz e as variáveis microscópicas foram as que apresentaram maior sensibilidade. Este estudo alerta sobre os possíveis efeitos prejudiciais que o glifosato pode provocar nos organismos não-alvo, sugerindo um maior controle quanto à utilização deste herbicida, a fim de mitigar o seu impacto ambiental.

2.
Braz. j. biol ; 84: e257039, 2024. tab, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1364528

RESUMO

The active ingredient glyphosate is the most commercialized herbicide on the world market due to its capability in eliminating weeds. However, it can harm the development of non-target organisms and threaten environmental quality. This study analyzed the effects of potentially toxic concentrations of glyphosate on germination, growth, cell cycle and genomic stability of Lactuca sativa L., and identified the most sensitive variables for assessing the toxicity of this herbicide to this biomonitor. Seeds of L. sativa were germinated in Petri dishes containing a sheet of filter paper moistened with 5 mL of a concentration of glyphosate (1.34, 3.35, 6.70, 10.05, 13.40 mg L-1). Controls consisted of distilled water (negative) and 3 mg L-1 CuSO4 (positive). Macroscopic and microscopic variables were analyzed. The germination of L. sativa was not affected by the concentrations of glyphosate. Root length and shoot height of the plants and the mitotic index decreased from the lowest concentration tested on. The chromosomal anomaly index and frequency of micronuclei increased by 3.2 and 22 times, respectively, with the presence of the lowest concentration of glyphosate compared to the negative control. The observed phytotoxic and cytogenotoxic effects demonstrate the negative influence that glyphosate has on the development of L. sativa. Root length and microscopic variables showed the highest sensitivity. This study warns of the possible harmful effects that glyphosate can have on non-target organisms and suggests greater control over the use of this herbicide to mitigate its environmental impact.


O ingrediente ativo glifosato é o herbicida mais comercializado do mercado mundial, pela sua capacidade de eliminar as plantas daninhas. No entanto, ele pode prejudicar o desenvolvimento dos organismos não-alvo e ameaçar a qualidade do ambiente. O estudo teve como objetivo analisar os efeitos de concentrações potencialmente tóxicas de glifosato sobre a germinação, o crescimento, o ciclo celular e a estabilidade genômica de Lactuca sativa L., e identificar as variáveis mais sensíveis para avaliar a toxicidade deste herbicida ao biomonitor. Sementes de L. sativa foram germinadas em placas de Petri contendo uma folha de papel-filtro umedecida com 5 mL das concentrações de glifosato (1,34, 3,35, 6,70, 10,05, 13,40 mg L-1). Os controles consistiram em água destilada (negativo) e 3 mg L-1 de CuSO4 (positivo). Variáveis macroscópicas e microscópicas foram analisadas. A germinação de L. sativa não foi afetada pelas concentrações de glifosato. O comprimento da raiz e a altura da parte aérea das plantas e o índice mitótico reduziram desde a menor concentração testada. O índice de anomalias cromossômicas e a frequência de micronúcleos aumentaram, respectivamente, 3,2 e 22 vezes na presença da menor concentração de glifosato em comparação ao controle negativo. Os efeitos fitotóxicos e citogenotóxicos observados demonstram a interferência negativa do herbicida no desenvolvimento de L. sativa. O comprimento da raiz e as variáveis microscópicas foram as que apresentaram maior sensibilidade. Este estudo alerta sobre os possíveis efeitos prejudiciais que o glifosato pode provocar nos organismos não-alvo, sugerindo um maior controle quanto à utilização deste herbicida, a fim de mitigar o seu impacto ambiental.


Assuntos
Meio Ambiente , Toxicidade , Herbicidas
3.
Eur Ann Otorhinolaryngol Head Neck Dis ; 140(6): 305-308, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37980265

RESUMO

INTRODUCTION: We illustrate the diagnostic method for chronic nasal dysfunction by an observation in which the clinical history was compared to preoperative responses on the DyNaChron self-administered questionnaire, with ENT interpretation of the sinonasal CT scan preceding and guiding nasal endoscopy. CASE REPORT: The initial suspicion of rhinitis medicamentosa was transformed by the radiological and endoscopic findings of chronic respiratory rhinitis signs. Prick tests showing sensitivity to dust mites then suggested an allergic origin of the mucosal inflammation, which affected neither the olfactory nose nor the paranasal sinuses. A septal deviation hampering visualization of the right ethmoidal reliefs completed the clinical picture. Inferior turbinate hypertrophy secondary to allergic inflammation could have been aggravated by prolonged daily use of nasal vasoconstrictors. Failure of medical treatment combining nasal lavage, topical corticosteroids and an attempt at weaning led to effective medical and surgical management combining septoplasty, bilateral inferior turbinoplasty, continuation of topical corticosteroids and initiation of allergen immunotherapy. In addition to complete relief of nasal obstruction and abandonment of nasal vasoconstrictors, improved sense of smell completed the restoration of nasal comfort. DISCUSSION: It is helpful to conceive the nose as being anatomically and pathophysiologically a triple organ and to evaluate therapy in terms of improvement in each symptom.


Assuntos
Pólipos Nasais , Rinite , Sinusite , Humanos , Rinite/diagnóstico , Rinite/etiologia , Rinite/terapia , Sinusite/complicações , Pólipos Nasais/complicações , Pólipos Nasais/diagnóstico , Pólipos Nasais/terapia , Descongestionantes Nasais/uso terapêutico , Endoscopia , Corticosteroides/uso terapêutico , Inflamação/complicações , Doença Crônica
4.
Braz J Biol ; 84: e257039, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35293479

RESUMO

The active ingredient glyphosate is the most commercialized herbicide on the world market due to its capability in eliminating weeds. However, it can harm the development of non-target organisms and threaten environmental quality. This study analyzed the effects of potentially toxic concentrations of glyphosate on germination, growth, cell cycle and genomic stability of Lactuca sativa L., and identified the most sensitive variables for assessing the toxicity of this herbicide to this biomonitor. Seeds of L. sativa were germinated in Petri dishes containing a sheet of filter paper moistened with 5 mL of a concentration of glyphosate (1.34, 3.35, 6.70, 10.05, 13.40 mg L-1). Controls consisted of distilled water (negative) and 3 mg L-1 CuSO4 (positive). Macroscopic and microscopic variables were analyzed. The germination of L. sativa was not affected by the concentrations of glyphosate. Root length and shoot height of the plants and the mitotic index decreased from the lowest concentration tested on. The chromosomal anomaly index and frequency of micronuclei increased by 3.2 and 22 times, respectively, with the presence of the lowest concentration of glyphosate compared to the negative control. The observed phytotoxic and cytogenotoxic effects demonstrate the negative influence that glyphosate has on the development of L. sativa. Root length and microscopic variables showed the highest sensitivity. This study warns of the possible harmful effects that glyphosate can have on non-target organisms and suggests greater control over the use of this herbicide to mitigate its environmental impact.


Assuntos
Herbicidas , Lactuca , Glicina/análogos & derivados , Glicina/toxicidade , Herbicidas/toxicidade , Sementes , Glifosato
6.
J Mycol Med ; 24(1): 25-8, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24411176

RESUMO

The objectives of the present study were to describe the fungal flora of the conjunctiva in clinically normal dogs in southern France and to compare the fungal flora from the conjunctiva and that from adjacent skin areas (medial canthus and nose). Fifty dogs aged from 5 months to 13 years were investigated for conjunctival fungal flora. Specimens were obtained from both conjunctivae and the skin of the medial canthus and from the surface of the nose using sterile cotton-wool swabs and a piece of sterile carpet, respectively. Identification of fungal colonies was achieved recording the genus level on the basis of macro- and microscopic features. Fourteen fungal genera (most frequently Alternaria, Cladosporium, Penicillium and Aspergillus) were isolated from the conjunctival fornix of 7 dogs (14%). There was no significant effect of sex or age on frequency of fungal isolation. Eleven dogs (22%) had a positive mycological culture from at least one eye. Fungi found in the conjunctival fornix of dogs might represent transient seeding from the environment, as suspected in other animal species. The presence of conjunctival fungal organisms was correlated to the presence of fungi on the skin.


Assuntos
Túnica Conjuntiva/microbiologia , Cães/microbiologia , Fungos/isolamento & purificação , Pele/microbiologia , Alternaria/isolamento & purificação , Animais , Aspergillus/isolamento & purificação , Feminino , França , Masculino , Penicillium/isolamento & purificação
7.
Nat Neurosci ; 4(9): 873-4, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11528416

RESUMO

Both ionotropic and metabotropic glutamate receptors (mGluRs) are involved in the behavioral effects of pyschostimulants; however, the specific contributions of individual mGluR subtypes remain unknown. Here we show that mice lacking the mGluR5 gene do not self-administer cocaine, and show no increased locomotor activity following cocaine treatment, despite showing cocaine-induced increases in nucleus accumbens (NAcc) dopamine (DA) levels similar to wild-type (WT) mice. These results demonstrate a significant contribution of mGlu5 receptors to the behavioral effects of cocaine, and suggest that they may be involved in cocaine addiction.


Assuntos
Cocaína/farmacologia , Atividade Motora/efeitos dos fármacos , Receptores de Glutamato Metabotrópico/fisiologia , Reforço Psicológico , Animais , Cocaína/administração & dosagem , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout/genética , Receptor de Glutamato Metabotrópico 5 , Receptores de Glutamato Metabotrópico/deficiência , Receptores de Glutamato Metabotrópico/genética , Valores de Referência , Autoadministração
8.
Psychopharmacology (Berl) ; 153(3): 315-20, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11271403

RESUMO

RATIONALE: Most smokers report smoking has an anxiolytic effect, which may contribute to nicotine dependence. OBJECTIVE: To examine effects in the social interaction test (SI) of anxiety after 4 weeks' self-administered nicotine (15 infusions of 0.03 mg/kg, totalling 0.45 mg/kg per day), and after 24 and 72 h of withdrawal. The effect of exposure to the operant chamber on withdrawal responses was also examined. METHODS: Animals were trained to self-administer saline or nicotine and after 4 weeks they were tested in SI after their daily self-administration session. Animals were retested after 24 and 72 h withdrawal, when they were either taken directly from the home cage or were tested 5 min after a 30-min exposure to the operant chamber. RESULTS: Compared with the saline control group, the animals that had been self-administering nicotine for 4 weeks showed decreased social interaction with no decrease in locomotor activity, indicating a significant anxiogenic effect of the nicotine infusions. There was no change in social interaction after 24 and 72 h withdrawal from chronic nicotine, regardless of whether or not the rats were exposed to the operant chamber just prior to being tested. CONCLUSIONS: Nicotine self-administration is not maintained because of its anxiolytic effect, but despite, or because of, its anxiogenic effect. There was no evidence of an anxiogenic response after either 24 or 72 h of withdrawal and thus increased anxiety on withdrawal from nicotine does not seem to contribute to nicotine self-administration.


Assuntos
Ansiedade/induzido quimicamente , Condicionamento Operante/efeitos dos fármacos , Atividade Motora/efeitos dos fármacos , Nicotina/farmacologia , Agonistas Nicotínicos/farmacologia , Síndrome de Abstinência a Substâncias , Animais , Ansiedade/psicologia , Condicionamento Operante/fisiologia , Masculino , Atividade Motora/fisiologia , Nicotina/administração & dosagem , Agonistas Nicotínicos/administração & dosagem , Ratos , Ratos Wistar , Autoadministração/psicologia , Comportamento Social , Síndrome de Abstinência a Substâncias/psicologia
9.
Neuropharmacology ; 35(11): 1557-65, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-9025103

RESUMO

The effects of the metabotropic glutamate receptor antagonist (+)-alpha-methyl-4-carboxyphenylglycine (MCPG) on performance in a water maze and in context-specific associative learning were examined in rats previously implanted with cannulae. MCPG (20.8 micrograms) injected intraventricularly (i.c.v.) before testing impaired the performance of rats in the spatial version of the Morris water maze, but 1/10 of this dose did not. Memory retention, evaluated 24 hr post-training, was also affected by the high dose of MCPG. However, performance in a cued version of the water maze was not impaired by the high dose, excluding effects of the drug on perceptual faculties. The effects of the MCPG were further characterized on performance in another hippocampus-dependent spatial learning task, the context-dependent fear conditioning task. MCPG (20.8 micrograms, i.c.v.) did not interfere with conditioned freezing to context in this task. For comparison, a group of rats was injected with the NMDA receptor blocker MK801. MK801 at a dose that disrupted the performance in the spatial version of the Morris water maze (0.08 mg/kg), significantly reduced freezing compared to controls. These experiments indicate that MCPG-sensitive metabotropic receptors may be required for only a restricted subset of spatial learning tasks, while NMDA receptors may play an integral role in all spatial learning.


Assuntos
Benzoatos/farmacologia , Antagonistas de Aminoácidos Excitatórios/farmacologia , Glicina/análogos & derivados , Aprendizagem em Labirinto/efeitos dos fármacos , Receptores de Glutamato Metabotrópico/antagonistas & inibidores , Animais , Condicionamento Psicológico/efeitos dos fármacos , Sinais (Psicologia) , Maleato de Dizocilpina/farmacologia , Relação Dose-Resposta a Droga , Medo/efeitos dos fármacos , Glicina/farmacologia , Injeções Intraventriculares , Masculino , Ratos , Percepção Espacial/efeitos dos fármacos
10.
G Ital Cardiol ; 22(11): 1301-8, 1992 Nov.
Artigo em Italiano | MEDLINE | ID: mdl-1297616

RESUMO

The purpose of this study was to evaluate the spectrum of morphologic and functional cardiac involvement in a selected population of patients with systemic lupus erythematosus (SLE) by means of echocardiography. Thirteen patients (2 male and 11 female) affected by SLE, mean age 41.9 years (range, 21-64), underwent M-Mode, two-dimensional and Doppler echocardiography. Eleven patients had renal disease and 3 of them were undergoing dialysis. One patient had findings of active disease. Six patients had systemic hypertension. None had a history suggestive of rheumatic fever or infective endocarditis. At echocardiographic study nine patients demonstrated findings of valvular involvement. These alterations were defined, according to the echocardiographic features, in two types: vegetation (verrucous Libman-Sacks endocarditis) and thickening. Vegetations were present in 6 patients, involving the mitral valve in all six and the aortic valve in three. The mitral valve vegetations were more frequent on the subannular portion of the posterior leaflet. Seven patients had valvular thickening: involvement of both mitral and aortic valve was present in five, and isolated mitral or aortic valve lesions in the remaining two patients. Combined valvular vegetation and thickening were observed in 4 patients. Eight patients had mild valvular dysfunction on Doppler examination: five isolated mitral regurgitation, two combined mitral and aortic regurgitation and one combined mitral stenosis and regurgitation. In agreement with previous reports, our study shows that valvular involvement in SLE is relatively frequent. Echocardiography can identify additional patterns of valvular lesions different from the known "verrucous Libman-Sacks endocarditis". The degree of valvular dysfunction is not important.


Assuntos
Valva Aórtica/diagnóstico por imagem , Ecocardiografia Doppler , Ecocardiografia , Lúpus Eritematoso Sistêmico/diagnóstico por imagem , Valva Mitral/diagnóstico por imagem , Adulto , Ecocardiografia/estatística & dados numéricos , Ecocardiografia Doppler/estatística & dados numéricos , Feminino , Doenças das Valvas Cardíacas/diagnóstico por imagem , Doenças das Valvas Cardíacas/epidemiologia , Doenças das Valvas Cardíacas/etiologia , Humanos , Lúpus Eritematoso Sistêmico/complicações , Lúpus Eritematoso Sistêmico/epidemiologia , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Estudos Retrospectivos
11.
G Ital Cardiol ; 22(7): 859-62, 1992 Jul.
Artigo em Italiano | MEDLINE | ID: mdl-1473661

RESUMO

Atrial septal aneurysm (ASA) is a known morphologic abnormality and has been largely investigated with two-dimensional echocardiography. Its association with other congenital or acquired diseases has also been described. However, the presence of ASA and concomitant Ebstein's anomaly in the same patient is a very unexpected finding in an adult subject. We therefore present the case of a young asymptomatic woman with this association.


Assuntos
Anomalia de Ebstein/diagnóstico por imagem , Aneurisma Cardíaco/diagnóstico por imagem , Comunicação Interatrial/diagnóstico por imagem , Adulto , Ecocardiografia , Feminino , Aneurisma Cardíaco/congênito , Átrios do Coração/diagnóstico por imagem , Septos Cardíacos/diagnóstico por imagem , Ventrículos do Coração/diagnóstico por imagem , Humanos
12.
G Ital Cardiol ; 20(12): 1179-81, 1990 Dec.
Artigo em Italiano | MEDLINE | ID: mdl-2083816

RESUMO

We report the case of a 75 year-old woman affected by cerebral thromboembolism associated with echocardiographic detection of sessile mass in the right atrium, which presented atrial septal discontinuity. The polypous and frayed aspect of the mass and its echogenic features were consistent with floating thromboembolus and enabled it to be distinguished from other masses. Moreover, the pattern of dynamical connection with atrial septal drop-out supported the diagnosis of paradoxical embolism.


Assuntos
Cardiopatias/diagnóstico , Embolia e Trombose Intracraniana/complicações , Trombose/diagnóstico , Idoso , Diagnóstico Diferencial , Ecocardiografia , Feminino , Cardiopatias/complicações , Humanos , Embolia e Trombose Intracraniana/diagnóstico , Trombose/complicações
13.
Acta Neurol Scand ; 73(1): 66-70, 1986 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-3006422

RESUMO

With the use of the Human Brain Tumor Stem Cell Assay (HBTSCA) in a cross-resistance study, four early (3-4) culture passages of human malignant gliomas (glioblastoma multiforme) were tested for in vitro chemosensitivity with three of the most effective single agents for brain tumor chemotherapy: BCNU, CCNU and cisplatinum (DDP). The shapes of the dose-response curves indicated complete cross-resistance between BCNU and CCNU, i.e. two chloroethyl-nitrosoureas sharing a common alkylating-carbamoylating activity, with no evident cross-resistance between the two nitrosoureas and the DDP, a DNA binder with a putatively different antitumor action. Probably because of differences in drug delivery kinetics or in the cytotoxic mechanism, DDP might play a role in the treatment of nitrosourea-resistant gliomas.


Assuntos
Neoplasias Encefálicas/tratamento farmacológico , Carmustina/uso terapêutico , Cisplatino/uso terapêutico , Glioblastoma/tratamento farmacológico , Lomustina/uso terapêutico , Células Cultivadas , Resistência a Medicamentos , Humanos , Ensaio Tumoral de Célula-Tronco
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