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1.
Med Oral Patol Oral Cir Bucal ; 27(3): e257-e264, 2022 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-35420070

RESUMEN

BACKGROUND: Liposuction is one of the most commonly performed cosmetic procedures worldwide. Complications associated with submental liposuction are rare. However, when they occur they are significant and can cause disfiguring consequences. The objective of this study was evaluated complications from submentual liposuction in literature and description of clinical experience of complication after submentual liposuction. MATERIAL AND METHODS: At first, a scoping review was carried out online search with no time restrictions for complications after submental liposuction was performed in the databases Medline / PubMed, Embase, and Web of Science. The variables analyzed were: age, sex, type of esthetic procedure, anesthesia, complications, time after Procedure, treatment, follow-up care, and sequelae. Then, a case of a patient with submental hematoma after an aesthetic procedure for submental liposuction was described. RESULTS: Firstly, 539 articles were selected, after application of the inclusion criteria, 4 studies were included. Most cases were female (8:1), with a mean age of 55.77 years. Postoperative complications were found, such as submental depression, submental edema, hypertrophic scar formation, scar contracture, cervical necrotizing fasciitis, Cervico-facial dystonia and transient facial nerve paralysis. The follow-up period for cases ranged from 3 to 12 months. The clinical case presented there was no sequelae. CONCLUSIONS: Submental liposuction requires the surgeon's attention. Anatomical knowledge, correct clinical and surgical management, diagnosis, and immediate approach to adverse situations are points that must be respected in this type of esthetic procedure to avoid more serious complications.


Asunto(s)
Lipectomía , Estética Dental , Femenino , Humanos , Lipectomía/efectos adversos , Lipectomía/métodos , Masculino , Persona de Mediana Edad , Cuello/cirugía , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/cirugía
2.
Genet Mol Res ; 14(2): 6303-11, 2015 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-26125833

RESUMEN

Knowledge of dominance effects should improve ge-netic evaluations, provide the accurate selection of purebred animals, and enable better breeding strategies, including the exploitation of het-erosis in crossbreeds. In this study, we combined genomic and pedi-gree data to study the relative importance of additive and dominance genetic variation in growth and carcass traits in an F2 pig population. Two GBLUP models were used, a model without a polygenic effect (ADM) and a model with a polygenic effect (ADMP). Additive effects played a greater role in the control of growth and carcass traits than did dominance effects. However, dominance effects were important for all traits, particularly in backfat thickness. The narrow-sense and broad-sense heritability estimates for growth (0.06 to 0.42, and 0.10 to 0.51, respectively) and carcass traits (0.07 to 0.37, and 0.10 to 0.76, respec-tively) exhibited a wide variation. The inclusion of a polygenic effect in the ADMP model changed the broad-sense heritability estimates only for birth weight and weight at 21 days of age.


Asunto(s)
Peso al Nacer/genética , Genómica , Herencia Multifactorial/genética , Porcinos/genética , Animales , Cruzamiento , Variación Genética , Carne , Linaje , Porcinos/crecimiento & desarrollo
3.
Sci Total Environ ; 942: 173757, 2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-38851329

RESUMEN

This study identified the occurrence of Holocene chronology hiatuses in the sedimentary record of the Patos-Mirim system caused by river avulsion processes, as well as evidence of sharp anthropogenic changes in the surrounding region of the lagoon water bodies. The presence of chronology hiatuses demonstrates the importance of considering the disturbance effect of paleo-drainage processes on the paleoenvironmental resolution and expression of the sedimentary record of such coastal plains. Anthropogenic activities especially those related to agriculture and forestry have increased significantly during the great acceleration, resulting in modifications of both the landscape and the environmental conditions of the lagoon bodies. Such impacts were clearly reflected in the sedimentary record where abrupt changes in palynological trends, sedimentary DNA, isotopic and granulometric analyses were inferred. The climatic conditions combined with regressive sea level can explain the chronology hiatuses. Pollen analyses demonstrated changes in the landscape, particularly indicated by the shift from Cyperaceae to Poaceae dominance after the 1960 CE. Therefore, all proxies together demonstrate the modification in the landscape and changes in the environment, clearly influenced by anthropogenic action from unsustainable agricultural practices.


Asunto(s)
Agricultura , Monitoreo del Ambiente , Sedimentos Geológicos , Ríos , Movimientos del Agua
5.
Genet Mol Res ; 12(3): 3193-200, 2013 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-24065662

RESUMEN

In order to provide the first cytogenetic data of naturalized and threatened goat breeds from northeastern Brazil, cytogenetic analyses were carried out in individuals of Repartida and Moxotó breeds raised in Bahia and Ceará States. Males and females of both breeds had 2n = 60, with 29 autosomal acrocentric pairs plus the sex chromosome pair. The number of nucleolar organizer region (NOR)-bearing chromosomes ranged from 6 to 8 per metaphase in Moxotó and Repartida goats, respectively. The active NORs in Repartida individuals were located exclusively at the terminal regions of the long arms, as usually detected in Bovidae. Otherwise, Moxotó specimens presented a large autosomal pair with NORs on short arms. GC-rich heterochromatin was detected at the centromeres in both breeds, although polymorphic terminal C-bands were visualized on pair 25 in Moxotó. In addition, GC-rich regions were detected at the terminal regions of the long arms of a single pair in Repartida and of 20 chromosomes in Moxotó goats. The differences in both the number and/or position of Ag-NORs and GC-rich sites between Repartida and Moxotó breeds represent efficient cytogenetic markers that can be used in the identification and conservation of the genetic integrity of each lineage. In spite of the small effective population size of these breeds, chromosomal abnormalities related to drift or inbreeding effects were absent in the samples analyzed.


Asunto(s)
Cromosomas/genética , Análisis Citogenético , Marcadores Genéticos/genética , Cabras/genética , Animales , Brasil , Femenino , Heterocromatina/genética , Cariotipificación , Masculino
6.
Neurochem Res ; 36(3): 412-8, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21161593

RESUMEN

This study was undertaken in order to characterize the role of the glutamate/aspartate transporter (GLAST) in the glutathione (GSH) efflux induced by glutamate. Our results demonstrated that retinal cell cultures exhibit two mechanisms of GSH release, one Na(+)-independent and other Na(+)-dependent. Glutamate and aspartate induced GSH efflux only in presence of Na(+). Treatment with PCD (L-trans-Pyrrolidine-2,4-dicarboxylate), a transportable glutamate uptake blocker, increased GSH release indicating that GSH can be carried by glutamate transporters in retinal cell cultures. Added to this, treatment with zinc ion cultures, a recognized inhibitor of GLAST blocked GSH efflux evoked by glutamate. Treatment with NMDA antagonist (MK-801) did not have any effect on the GSH release induced by glutamate. These results suggest that glutamate induces GLAST-mediated release of GSH from retinal cell cultures and this could represent an important mechanism of cellular protection against glutamate toxicity in the CNS.


Asunto(s)
Sistema de Transporte de Aminoácidos X-AG/metabolismo , Ácido Glutámico/farmacología , Glutatión/metabolismo , Retina/citología , Animales , Ácido Aspártico/farmacología , Células Cultivadas , Embrión de Pollo , Ácidos Dicarboxílicos/farmacología , Ácido Glutámico/metabolismo , Inhibidores de la Captación de Neurotransmisores/farmacología , Pirrolidinas/farmacología , Retina/efectos de los fármacos
7.
Eur J Dent Educ ; 15(1): 31-5, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21226803

RESUMEN

AIM: To examine how much final-year undergraduate dental students know about postural dental ergonomic requirements, and how well they apply these requirements clinically. BACKGROUND: Dentists are vulnerable to diverse mechanical (e.g. postural) and non-mechanical occupational risks. MATERIALS AND METHODS: Eight postural requirements found in normalising documents were identified, reproduced, photographed, and analysed to develop a test of visual perception (TVP). Photographs of the 69 participating students were taken during their clinical care to ascertain ergonomics compliance, after which the students were administered the TVP. Pearson's test was used to correlate the level of knowledge (TVP) and its clinical application (photographic analysis) among the 552 observations made for each test (total of 1104 observations). RESULTS: 65.7% of the TVP questions were answered correctly and 35% of the photographic cases were in compliance with ergonomic requirements (+ 0.67, P < 0.0001). CONCLUSION: The knowledge of ergonomics postural requirements and their clinical application among the dental students surveyed were not satisfactory. The reasons for the learning difficulties encountered by the students should be identified to improve the learning process. The didactic use of digital images in this study may help in this endeavour.


Asunto(s)
Ergonomía , Conocimientos, Actitudes y Práctica en Salud , Enfermedades Profesionales/prevención & control , Postura , Estudiantes de Odontología/psicología , Femenino , Humanos , Masculino , Fotograbar , Proyectos Piloto , Encuestas y Cuestionarios , Percepción Visual
8.
Ecotoxicol Environ Saf ; 73(1): 101-7, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19481804

RESUMEN

Thiamethoxam is a neonicotinoid insecticide, a group of pesticides that acts selectively on insect nicotinic acetylcholine receptors (nAChRs), with only a little action on mammalian nAChRs. Nevertheless, the selectivity of neonicotinoids for the insect nAChRs may change when these substances are metabolized. Therefore, we aimed to determine the potential effects of thiamethoxam on mammalian brain, testing the performance in the open field and elevated plus-maze of rats exposed to this insecticide and, in order to establish the neurochemical endpoints, we measured the acetylcholinesterase activity in different brain regions (hippocampus, striatum and cortex) and the high-affinity choline uptake (HACU) in synaptosomes from rat hippocampus. Treated animals received thiamethoxam (25, 50 or 100mg/kg) for 7 consecutive days. The results showed that treatment with thiamethoxam induced an increase in the anxiety behavior at two doses (50 or 100mg/kg). Moreover, there was a significant decrease in both HACU and acetylcholinesterase activity. Our hypothesis is that thiamethoxam (or its metabolites) could be acting on the central rats nAChRs. This would produce an alteration on the cholinergic transmission, modulating the anxiety behavior, acetylcholinesterase levels and HACU.


Asunto(s)
Conducta Animal/efectos de los fármacos , Encéfalo/efectos de los fármacos , Insecticidas/toxicidad , Nitrocompuestos/toxicidad , Oxazinas/toxicidad , Sistema Nervioso Parasimpático/efectos de los fármacos , Tiazoles/toxicidad , Acetilcolinesterasa/metabolismo , Animales , Encéfalo/enzimología , Colina/metabolismo , Relación Dosis-Respuesta a Droga , Masculino , Aprendizaje por Laberinto/efectos de los fármacos , Actividad Motora/efectos de los fármacos , Neonicotinoides , Ratas , Ratas Wistar , Tiametoxam
9.
Braz J Med Biol Res ; 53(4): e8604, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32294697

RESUMEN

Maraba virus is a member of the genus Vesiculovirus of the Rhabdoviridae family that was isolated in 1983 from sandflies captured in the municipality of Maraba, state of Pará, Amazônia, Brazil. Despite 30 years having passed since its isolation, little is known about the neuropathology induced by the Maraba virus. Accordingly, in this study the histopathological features, inflammatory glial changes, cytokine concentrations, and nitric oxide activity in the encephalon of adult mice subjected to Maraba virus nostril infection were evaluated. The results showed that 6 days after intranasal inoculation, severe neuropathological-associated disease signs appeared, including edema, necrosis and pyknosis of neurons, generalized congestion of encephalic vessels, and intra- and perivascular meningeal lymphocytic infiltrates in several brain regions. Immunolabeling of viral antigens was observed in almost all central nervous system (CNS) areas and this was associated with intense microglial activation and astrogliosis. Compared to control animals, infected mice showed significant increases in interleukin (IL)-6, tumor necrosis factor (TNF)-α, interferon (INF)-γ, MCP-1, nitric oxide, and encephalic cytokine levels. We suggest that an exacerbated inflammatory response in several regions of the CNS of adult BALB/c mice might be responsible for their deaths.


Asunto(s)
Meningoencefalitis/complicaciones , Estomatitis Vesicular/complicaciones , Animales , Astrocitos/metabolismo , Brasil , Citocinas/análisis , Modelos Animales de Enfermedad , Citometría de Flujo , Masculino , Meningoencefalitis/patología , Ratones , Ratones Endogámicos BALB C , Microglía/metabolismo , Óxido Nítrico/análisis , Estomatitis Vesicular/patología , Vesiculovirus
10.
Braz J Med Biol Res ; 52(5): e8026, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31038577

RESUMEN

Carassius auratus is a teleost fish that has been largely used in behavioral studies. However, little is known about potential environmental influences on its performance of learning and memory tasks. Here, we investigated this question in C. auratus, and searched for potential correlation between exercise and visuospatial enrichment with the total number of telencephalic glia and neurons. To that end, males and females were housed for 183 days in either an enriched (EE) or impoverished environment (IE) aquarium. EE contained toys, natural plants, and a 12-hour/day water stream for voluntary exercise, whereas the IE had none of the above. A third plus-maze aquarium was used for spatial and object recognition tests. Different visual clues in 2 of its 4 arms were used to guide fish to reach the criteria to complete the task. The test consisted of 30 sessions and was concluded when each animal performed three consecutive correct choices or seven alternated, each ten trials. Learning rates revealed significant differences between EE and IE fish. The optical fractionator was used to estimate the total number of telencephalic cells that were stained with cresyl violet. On average, the total number of cells in the subjects from EE was higher than those from subjects maintained in IE (P=0.0202). We suggest that environmental enrichment significantly influenced goldfish spatial learning and memory abilities, and this may be associated with an increase in the total number of telencephalic cells.


Asunto(s)
Proliferación Celular/fisiología , Peces/fisiología , Aprendizaje Espacial/fisiología , Memoria Espacial/fisiología , Telencéfalo/metabolismo , Animales , Conducta Animal/fisiología , Recuento de Células , Femenino , Masculino , Condicionamiento Físico Animal
11.
Cytogenet Genome Res ; 122(2): 163-8, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-19096212

RESUMEN

Triportheus fish species present 2n = 52 chromosomes. The karyotypes show similar macrostructure and a ZZ/ZW sex chromosome system, which probably represents synapomorphy for the genus. A probe of the Z chromosome was obtained from T. nematurus through microdissection, followed by unspecific amplification via DOP-PCR. This probe was used for WCP (whole chromosome painting) through fluorescent in situ hybridization (FISH) in several other Triportheus species, to analyze the differentiation of the ZZ/ZW system. The homology between this probe and chromosomes of species from other genera, putatively related to Triportheus, was also examined to search for evidence about evolution of their sex chromosomes. Complete homology was found among the Z chromosomes of all Triportheus species, while only small positive signals were found on the W chromosomes. Hybridization signals were absent in species from other genera. The present results reinforce both the conservative nature of Z chromosomes and the hypothesis that the ZZ/ZW sex chromosome system is a synapomorphic feature of Triportheus. On the other hand, besides reduction of size, W chromosomes have undergone accentuated composition changes in relation to Z chromosomes, since only a small region, usually located in the short arm, kept homology with the Z chromosomes.


Asunto(s)
Pintura Cromosómica/métodos , Peces/genética , Microdisección/métodos , Cromosomas Sexuales/genética , Animales , Femenino , Peces/clasificación , Masculino , Filogenia
12.
J Ethnopharmacol ; 118(2): 246-51, 2008 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-18513903

RESUMEN

Physalis angulata is a popular medicine used in Brazil due to its anti-inflammatory effects, but the pharmacological mechanisms underlying these actions remain to be better understood. In the present work, lyophilized aqueous extract from the roots of Physalis angulata Linneu (AEPa) was used to control the inflammatory response induced by the injection of 1% carrageenan into subcutaneous rat's air pouches. Adenosine deaminase (ADA) activity, nitrite level, and prostaglandin E(2) (PGE(2)) level were used to evaluate the action of inflammatory mediators. Tumor growth factor-beta (TGF-beta) level was used as a bioindicator of immunomodulatory response. Rats were injected with vehicle, indomethacin, or AEPa (0.5 mg/kg, 1 mg/kg, and 5 mg/kg i.p.), 1h before carrageenan administration. AEPa at 0.5 mg/kg had no effect. However, 1mg/kg of AEPa showed significant anti-inflammatory effects, decreasing exudate volume, total number of inflammatory cells, ADA activity, nitrite level, and PGE(2) level in 50%, 41%, 20%, 60%, and 41%, respectively. The anti-inflammatory effects of 5 mg/kg AEPa appeared to be more effective than those of 1 mg/kg AEPa (84%, 80%, 43%, 70%, and 75%, respectively). In addition, TGF-beta level was upregulated to 9700 pg/ml after 5mg/kg AEPa, in comparison with 160 pg/ml in the vehicle-treated group, and 137 pg/ml in the indomethacin-treated group. The results indicate that AEPa exerts powerful anti-inflammatory and immunomodulatory activities, interfering with the cyclooxygenase pathway, lymphocyte proliferation, NO, and TGF-beta production.


Asunto(s)
Antiinflamatorios/farmacología , Inflamación/tratamiento farmacológico , Physalis/química , Extractos Vegetales/farmacología , Adenosina Desaminasa/efectos de los fármacos , Adenosina Desaminasa/metabolismo , Animales , Antiinflamatorios/administración & dosificación , Antiinflamatorios/aislamiento & purificación , Brasil , Dinoprostona/metabolismo , Relación Dosis-Respuesta a Droga , Indometacina/farmacología , Linfocitos/efectos de los fármacos , Linfocitos/metabolismo , Masculino , Medicina Tradicional , Óxido Nítrico/metabolismo , Extractos Vegetales/administración & dosificación , Raíces de Plantas , Ratas , Ratas Wistar , Factor de Crecimiento Transformador beta/efectos de los fármacos , Factor de Crecimiento Transformador beta/metabolismo , Regulación hacia Arriba/efectos de los fármacos
13.
Environ Technol ; 29(8): 891-8, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18724644

RESUMEN

In the present work ultraviolet (UV)-visible spectra of water samples collected at the outlet of a fuel park wastewater treatment plant, including biological treatment, were acquired and used for the development of partial least squares (PLS) calibration models for the fast and simple estimation of total organic carbon (TOC). Three different PLS models were developed and compared on the basis of a common spectral range. The first model was obtained using spectra of raw samples, the second using spectra of diluted samples, to assess signal saturation in the UV region, and the third using spectra of both diluted and raw samples, in order to expand the narrow interval of TOC concentration values present in the original dataset. The root mean squared error of cross-validation values for the developed PLS models were 2.3, 1.0 and 4.4 mg Cl(-1), respectively, and the validation results where highly satisfactory (root mean squared error of prediction values of 1.8, 0.8 and 4.5 mg Cl(-1), respectively).


Asunto(s)
Monitoreo del Ambiente/métodos , Residuos Industriales/análisis , Compuestos Orgánicos/análisis , Contaminantes Químicos del Agua/análisis , Calibración , Análisis de los Mínimos Cuadrados , Espectrofotometría Ultravioleta
14.
Braz J Med Biol Res ; 40(7): 949-55, 2007 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-17653448

RESUMEN

Several studies have reported that symptoms of anxiety and depression are significantly associated with diseases characterized by painful crises. However, there is little information about the psychological aspects of recurrent painful episodes of renal stone disease. Our objective was to evaluate the association of symptoms of anxiety, depression and recurrent painful renal colic in a case-control study involving 64 subjects (32 cases/32 controls) matched for age and sex. Cases were outpatients with a confirmed diagnosis of nephrolithiasis as per their case history, physical examination, image examination and other laboratory exams. Patients had a history of at least two episodes within a 3-year period, and were currently in an intercrisis interval. The control group consisted of subjects seen at the Ophthalmology Outpatient Clinic of this University Hospital with only eye refraction symptoms, and no other associated disease. Symptoms of anxiety were evaluated by the State-Trait Anxiety Inventory and symptoms of depression by the Beck Depression Inventory. Statistically significant differences were observed between patients with nephrolithiasis and controls for anxiety state (P = 0.001), anxiety trait (P = 0.005) and symptoms of depression (odds ratio = 3.74; 95%CI = 1.31-10.62). The Beck Depression Inventory showed 34.5% of respondents with moderate and 6% with severe levels of depression. There was a significant linear correlation between symptoms of anxiety (P = 0.002) and depression (P < 0.001) and the number of recurrent colic episodes (anxiety-state: P = 0.016 and anxiety-trait: P < 0.001). These data suggest an association between recurrent renal colic and symptoms of both anxiety and depression.


Asunto(s)
Ansiedad/psicología , Cólico/psicología , Depresión/psicología , Nefrolitiasis/psicología , Adulto , Anciano , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Persona de Mediana Edad , Escalas de Valoración Psiquiátrica , Recurrencia , Encuestas y Cuestionarios
15.
Braz J Med Biol Res ; 39(11): 1493-9, 2006 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17146562

RESUMEN

In previous studies, we demonstrated biphasic purinergic effects on prolactin (PRL) secretion stimulated by an adenosine A2 agonist. In the present study, we investigated the role of the activation of adenosine A1 receptors by (R)-N6-(2-phenylisopropyl)adenosine (R-PIA) at the pituitary level in in vitro PRL secretion. Hemipituitaries (one per cuvette in five replicates) from adult male rats were incubated. Administration of R-PIA (0.001, 0.01, 0.1, 1, and 10 microM) induced a reduction of PRL secretion into the medium in a U-shaped dose-response curve. The maximal reduction was obtained with 0.1 microM R-PIA (mean +/- SEM, 36.01 +/- 5.53 ng/mg tissue weight (t.w.)) treatment compared to control (264.56 +/- 15.46 ng/mg t.w.). R-PIA inhibition (0.01 microM = 141.97 +/- 15.79 vs control = 244.77 +/- 13.79 ng/mg t.w.) of PRL release was blocked by 1 microM cyclopentyltheophylline, a specific A1 receptor antagonist (1 microM = 212.360 +/- 26.560 ng/mg t.w.), whereas cyclopentyltheophylline alone (0.01, 0.1, 1 microM) had no effect. R-PIA (0.001, 0.01, 0.1, 1 microM) produced inhibition of PRL secretion stimulated by both phospholipase C (0.5 IU/mL; 977.44 +/- 76.17 ng/mg t.w.) and dibutyryl cAMP (1 mM; 415.93 +/- 37.66 ng/mg t.w.) with nadir established at the dose of 0.1 microM (225.55 +/- 71.42 and 201.9 +/- 19.08 ng/mg t.w., respectively). Similarly, R-PIA (0.01 microM) decreased (242.00 +/- 24.00 ng/mg t.w.) the PRL secretion stimulated by cholera toxin (0.5 mg/mL; 1050.00 +/- 70.00 ng/mg t.w.). In contrast, R-PIA had no effect (468.00 +/- 34.00 ng/mg t.w.) on PRL secretion stimulation by pertussis toxin (0.5 mg/mL; 430.00 +/- 26.00 ng/mg t.w.). These results suggest that inhibition of PRL secretion after A1 receptor activation by R-PIA is mediated by a Gi protein-dependent mechanism.


Asunto(s)
Adenosina/análogos & derivados , Adenohipófisis/efectos de los fármacos , Prolactina/metabolismo , Receptor de Adenosina A1/metabolismo , Transducción de Señal , Adenosina/farmacología , Animales , Toxina del Cólera/farmacología , CMP Cíclico/análogos & derivados , CMP Cíclico/farmacología , Relación Dosis-Respuesta a Droga , Masculino , Toxina del Pertussis/farmacología , Adenohipófisis/metabolismo , Radioinmunoensayo , Ratas , Ratas Wistar , Fosfolipasas de Tipo C/farmacología
16.
Braz J Med Biol Res ; 39(3): 415-8, 2006 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16501822

RESUMEN

The visual system is a potential target for methylmercury (MeHg) intoxication. Nevertheless, there are few studies about the cellular mechanisms of toxicity induced by MeHg in retinal cells. Various reports have indicated a critical role for nitric oxide synthase (NOS) activation in modulating MeHg neurotoxicity in cerebellar and cortical regions. The aim of the present study is to describe the effects of MeHg on cell viability and NOS activation in chick retinal cell cultures. For this purpose, primary cultures were prepared from 7-day-old chick embryos: retinas were aseptically dissected and dissociated and cells were grown at 37 degrees C for 7-8 days. Cultures were exposed to MeHg (10 microM, 100 microM, and 1 mM) for 2, 4, and 6 h. Cell viability was measured by MTT method and NOS activity by monitoring the conversion of L-[H3]-arginine to L-[H3]-citrulline. The incubation of cultured retina cells with 10 and 100 microM MeHg promoted an increase of NOS activity compared to control (P < 0.05). Maximum values (P < 0.05) were reached after 4 h of MeHg incubation: increases of 81.6 +/- 5.3 and 91.3 +/- 3.7%, respectively (data are reported as mean +/- SEM for 4 replicates). MeHg also promoted a concentration- and time-dependent decrease in cell viability, with the highest toxicity (a reduction of about 80% in cell viability) being observed at the concentration of 1 mM and after 4-6 h of incubation. The present study demonstrates for the first time the modulation of MeHg neurotoxicity in retinal cells by the nitrergic system.


Asunto(s)
Compuestos de Metilmercurio/toxicidad , Óxido Nítrico Sintasa/metabolismo , Retina/efectos de los fármacos , Animales , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Embrión de Pollo , Retina/citología , Factores de Tiempo
17.
Chemosphere ; 65(5): 786-91, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16650456

RESUMEN

In the context of the high application potentials for on-line measurements in wastewater quality monitoring, UV spectroscopy has received recent attention. In the present work UV spectrophotometric analyses were coupled to principal component analysis (PCA) and cluster analysis (CA) to characterize samples taken from a fuel park wastewater treatment plant and to attempt preliminary contaminant identification in the treated wastewater. The score plot resulting from PCA identified two different groups of spectra, one including the influents to the biological reactor and the other the treated wastewater samples. Among the latter, weekday and weekend samples could be further distinguished. The same groups of samples were identified in a dendrogram from CA. The score plot and the dendrogram also allowed the tentative identification of employed process chemicals (lubricant and detergents) as residual contaminants in the treated effluent.


Asunto(s)
Monitoreo del Ambiente/métodos , Residuos Industriales , Contaminantes Químicos del Agua/análisis , Abastecimiento de Agua/análisis , Agua/análisis , Análisis por Conglomerados , Análisis de Componente Principal , Espectrofotometría Ultravioleta/métodos , Eliminación de Residuos Líquidos
18.
Braz J Med Biol Res ; 49(1): e5005, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26577847

RESUMEN

The semipalmated sandpiper Calidris pusilla and the spotted sandpiper Actitis macularia are long- and short-distance migrants, respectively. C. pusilla breeds in the sub-arctic and mid-arctic tundra of Canada and Alaska and winters on the north and east coasts of South America. A. macularia breeds in a broad distribution across most of North America from the treeline to the southern United States. It winters in the southern United States, and Central and South America. The autumn migration route of C. pusilla includes a non-stop flight over the Atlantic Ocean, whereas autumn route of A. macularia is largely over land. Because of this difference in their migratory paths and the visuo-spatial recognition tasks involved, we hypothesized that hippocampal volume and neuronal and glial numbers would differ between these two species. A. macularia did not differ from C. pusilla in the total number of hippocampal neurons, but the species had a larger hippocampal formation and more hippocampal microglia. It remains to be investigated whether these differences indicate interspecies differences or neural specializations associated with different strategies of orientation and navigation.


Asunto(s)
Migración Animal , Charadriiformes/anatomía & histología , Hipocampo/anatomía & histología , Microglía/citología , Neuronas/citología , Animales , Cruzamiento , Charadriiformes/fisiología , Hipocampo/citología , Inmunohistoquímica , Tamaño de los Órganos , Orientación , Fotomicrografía , Filogenia , Navegación Espacial/fisiología , Especificidad de la Especie , Telencéfalo/anatomía & histología
19.
Braz. j. med. biol. res ; 53(4): e8604, 2020. graf
Artículo en Inglés | LILACS | ID: biblio-1100926

RESUMEN

Maraba virus is a member of the genus Vesiculovirus of the Rhabdoviridae family that was isolated in 1983 from sandflies captured in the municipality of Maraba, state of Pará, Amazônia, Brazil. Despite 30 years having passed since its isolation, little is known about the neuropathology induced by the Maraba virus. Accordingly, in this study the histopathological features, inflammatory glial changes, cytokine concentrations, and nitric oxide activity in the encephalon of adult mice subjected to Maraba virus nostril infection were evaluated. The results showed that 6 days after intranasal inoculation, severe neuropathological-associated disease signs appeared, including edema, necrosis and pyknosis of neurons, generalized congestion of encephalic vessels, and intra- and perivascular meningeal lymphocytic infiltrates in several brain regions. Immunolabeling of viral antigens was observed in almost all central nervous system (CNS) areas and this was associated with intense microglial activation and astrogliosis. Compared to control animals, infected mice showed significant increases in interleukin (IL)-6, tumor necrosis factor (TNF)-α, interferon (INF)-γ, MCP-1, nitric oxide, and encephalic cytokine levels. We suggest that an exacerbated inflammatory response in several regions of the CNS of adult BALB/c mice might be responsible for their deaths.


Asunto(s)
Animales , Masculino , Conejos , Estomatitis Vesicular/complicaciones , Meningoencefalitis/complicaciones , Brasil , Astrocitos/metabolismo , Citocinas/análisis , Vesiculovirus , Microglía/metabolismo , Modelos Animales de Enfermedad , Estomatitis Vesicular/patología , Citometría de Flujo , Meningoencefalitis/patología , Ratones Endogámicos BALB C , Óxido Nítrico/análisis
20.
Braz J Med Biol Res ; 48(8): 691-6, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26108095

RESUMEN

Heavy metals, such as methylmercury, are key environmental pollutants that easily reach human beings by bioaccumulation through the food chain. Several reports have demonstrated that endocrine organs, and especially the pituitary gland, are potential targets for mercury accumulation; however, the effects on the regulation of hormonal release are unclear. It has been suggested that serum prolactin could represent a biomarker of heavy metal exposure. The aim of this study was to evaluate the effect of methylmercury on prolactin release and the role of the nitrergic system using prolactin secretory cells (the mammosomatotroph cell line, GH3B6). Exposure to methylmercury (0-100 µM) was cytotoxic in a time- and concentration-dependent manner, with an LC50 higher than described for cells of neuronal origin, suggesting GH3B6 cells have a relative resistance. Methylmercury (at exposures as low as 1 µM for 2 h) also decreased prolactin release. Interestingly, inhibition of nitric oxide synthase by N-nitro-L-arginine completely prevented the decrease in prolactin release without acute neurotoxic effects of methylmercury. These data indicate that the decrease in prolactin production occurs via activation of the nitrergic system and is an early effect of methylmercury in cells of pituitary origin.


Asunto(s)
Compuestos de Metilmercurio/toxicidad , Óxido Nítrico Sintasa/antagonistas & inhibidores , Nitroarginina/toxicidad , Hipófisis/efectos de los fármacos , Prolactina/metabolismo , Animales , Bovinos , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Caballos , Humanos , Hipófisis/metabolismo , Neoplasias Hipofisarias , Ratas
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