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1.
Morphologie ; 108(362): 100784, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38696841

RESUMEN

Histology is part of the curricular base of all health courses, being the basis for understanding the composition of all tissues in the human body. Over the years, more and more technologies have entered the academic environment, with the aim of improving the teaching and learning process. Thus, the objective of this work was to conduct a systematic review on the use of digital technologies in teaching histology. The PICo strategy was used to develop the guiding question and the results were presented in a Prisma Flow. The following platforms were used to search for articles: PubMed, Embase. Web of Science, Science Direct, Medline, Scielo, Periódicos CAPES and LILACS, Open Gray and Google Scholar, with a time limit between 2012 and 2022. The results showed that this area is still little explored, with there not being a wide range of technologies being used and applied in teaching, with gamification and virtual microscopy being the most applied. However, it was realized that the use of these technologies can improve student performance and increase their interest in the subject. Therefore, these tools are great methods to reduce difficulties and encourage the development of a more receptive environment for the histology teaching and learning process.

2.
Cryo Letters ; 44(3): 151-159, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37883168

RESUMEN

BACKGROUND: Semen cryopreservation is a biotechnology used frequently in animal production; however, there are some obstacles, such as those caused by high levels of reactive oxygen species (ROS). Moringa oleifera (MO) is known as a potent source of antioxidants and might be an important adjuvant. OBJECTIVE: The objective of this study was to determine the effect of different concentrations of MO extract supplementation on goat semen cryopreservation efficiency. MATERIALS AND METHODS: Ejaculates (n=6) from four goat breeders were pooled and diluted in skimmed milk (SM) or Tris-egg yolk (TEY)-based extenders and supplemented with different concentrations of MO extract (0, 1, 2 and 5 mg/mL). After the freeze-thaw cycle, sperm kinetics and viability were assessed. RESULTS: With the SM extender, straightness, wobble and plasma membrane integrity were lower than in the control group (P < 0.05). With the TEY extender, wobble was lower in with 5 mg/mL MO extract than in the control group (P < 0.05). As regards sperm ultrastructure, evaluated by SEM, the MO extract, regardless of the diluent used, damaged the membrane of sperm cells in a dose-dependent manner. CONCLUSION: The addition of aqueous extract of MO leaves in both diluents at all concentrations tested affects the parameters of sperm progressivity and damages the plasma membrane in a dose-dependent manner. DOI: 10.54680/fr23310110712.


Asunto(s)
Moringa oleifera , Preservación de Semen , Masculino , Animales , Congelación , Cabras , Criopreservación/veterinaria , Motilidad Espermática , Preservación de Semen/veterinaria , Semillas , Espermatozoides , Yema de Huevo/química , Crioprotectores/farmacología
3.
Genet Mol Res ; 12(1): 370-80, 2013 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-23420361

RESUMEN

We developed six microsatellite markers for the fall armyworm Spodoptera frugiperda (Lepidoptera: Noctuidae). The SSR loci were isolated with enriched genomic library protocol by using native individuals as a genome source for markers. These loci were characterized in 48 individuals and they were tested for the ability to identify candidate migrants exchanged among the samples. The number of alleles per locus ranged from 5 to 18 (10.8 on average). The observed polymorphism information content ranged from 0.172 to 0.891. Beside the lower efficiency to obtain SSR loci, the six microsatellites were polymorphic and sufficiently discriminant for the genetic studies of S. frugiperda; it allowed us to identify migrants with both NJ clustering and the Bayesian methods. These markers will be useful for molecular ecology studies of this highly polyphagous species in order to understand the processes that determine genetic differentiation in the complex agro-ecosystems that it infests and improve local integrated pest management practices.


Asunto(s)
Repeticiones de Microsatélite , Spodoptera/genética , Alelos , Animales , Teorema de Bayes , Genoma/genética , Biblioteca Genómica , Polimorfismo Genético
4.
Clin Exp Med ; 6(4): 166-70, 2006 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17191108

RESUMEN

Fibroadenoma (FA) is a benign breast tumour that occurs in about 25% of women. Cytogenetic studies suggest that numerical chromosomal aberrations may contribute to tumorigenesis, but chromosomal instability is still poorly characterised in breast cancer. The aim of this study was to investigate numerical alterations of chromosome 21 in 15 breast FAs. All samples were analysed by classical cytogenetics and by fluorescence in situ hybridisation (FISH) for chromosome 21 DNA sequences. Classical cytogenetics analysis showed that all cells were diploidies with modal number varying between 43 and 47 chromosomes, and clonal chromosome alterations in 46.7% of tumours. Clonal numerical alterations involved, preferentially, chromosomes 8, 10, 12, 16 and 21. FISH analysis showed a statistically significant difference for chromosome 21 monosomy between seven samples and control group. This monosomy varied from 24.5% to 43.5% of analysed cells. The presence of chromosomal alterations in FAs may be a consequence of the proliferation process and is probably not related to the aetiology of this type of lesion. The study of benign proliferations and comparison with chromosome alterations in their malignant counterparts should result in an understanding of the genes acting in cell proliferation alone and those that cause these cells to both undergo malignant transformation and become invasive.


Asunto(s)
Aneuploidia , Neoplasias de la Mama/genética , Cromosomas Humanos Par 21/genética , Fibroadenoma/genética , Hibridación Fluorescente in Situ , Adolescente , Adulto , Análisis Citogenético , Femenino , Humanos , Monosomía , Estadística como Asunto
5.
Biochem Pharmacol ; 51(10): 1331-40, 1996 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-8787549

RESUMEN

The involvement of apoptosis in the mechanism of cell death induced by six clinically relevant anticancer drugs [methotrexate (MTX), doxorubicin (ADR), daunorubicin (DNR), vincristine (VCR), 6-mercaptopurine (6MP), and prednisolone (PRD)] in human leukemic T-lymphocytes (CCRF-CEM and Jurkat) was investigated by analysing changes in cell size and morphology, changes in membrane integrity, alterations in [Ca2+]i and induction of DNA fragmentation. MTX, ADR, and DNR showed pronounced dose- and time-dependent cytotoxic effects on both cell lines, whereas cell viability was not considerably reduced by 6MP or PRD. On the other hand, the cytotoxic activity of VCR was much higher on Jurkat cells than on CEM cells. With the exception of 6MP and PRD, all the other compounds induced extensive chromatin condensation, nuclear fragmentation, plasma membrane blebbing, and formation of apoptotic bodies and fragmentation of DNA in both cell lines. Occurrence of DNA fragmentation always preceded loss of membrane integrity. These observation are consistent with cell death being mediated by apoptosis. Significant increases in [Ca2+]i were only observed in CEM cells preincubated with MTX or DNR (10 microM). In contrast, MTX as well as VCR induced a reduction in the basal intracellular Ca2+ concentration in Jurkat T-cells. Although the ability to induce changes in [Ca2+]i correlated with higher cytotoxic potency of the anticancer drugs, a causal relationship between increased [Ca2+] and induction of apoptosis could not be clearly established. These results, therefore, suggest no determinant role for Ca2+ in triggering the process of endonucleolytic cleavage of genomic DNA in these leukemic T-lymphocytes.


Asunto(s)
Antineoplásicos/farmacología , Muerte Celular/efectos de los fármacos , Linfocitos T/efectos de los fármacos , Apoptosis , Recuento de Células/efectos de los fármacos , Daunorrubicina/farmacología , Relación Dosis-Respuesta a Droga , Doxorrubicina/farmacología , Humanos , Metotrexato/farmacología , Factores de Tiempo
6.
Science ; 268(5207): 15-6, 1995 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-17755217
7.
Biosci Rep ; 14(1): 15-24, 1994 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8032005

RESUMEN

We have studied the role of hydrophobic interactions in the fusion activity of two lipid enveloped viruses, influenza and Sendai. Using the fluorescent probe ANS (1-aminonaphtalene-8-sulfonate) we have shown that low-pH-dependent influenza virus activation involves a marked increase in the viral envelope hydrophobicity. The effect of dehydrating agents on the fusion activity of both viruses towards model lipid membranes was studied using a fluorescence dequenching assay. Dehydrating agents such as dimethylsulfoxide and dimethylsulfone greatly enhanced the initial rate of the fusion process, the effect of dimethylsulfone doubling that of dimethylsulfoxide. The effect of poly(ethylene glycol) on the fusion process was found to be dependent on the polymer concentration and molecular weight. In general, similar observations were made for both viruses. These results stress the importance of dehydration and hydrophobic interactions in the fusion activity of influenza and Sendai viruses, and show that these factors may be generally involved in membrane fusion events mediated by many other lipid enveloped viruses.


Asunto(s)
Fusión de Membrana , Orthomyxoviridae/fisiología , Virus de la Parainfluenza 1 Humana/fisiología , Dimetilsulfóxido/farmacología , Concentración de Iones de Hidrógeno , Liposomas , Naftalenosulfonatos , Polietilenglicoles/farmacología , Sulfonas/farmacología
8.
Mutat Res ; 496(1-2): 15-21, 2001 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-11551476

RESUMEN

Agaricus blazei Murrill extracts have previously been shown to have anticarcinogenic and antimutagenic properties. These results suggest that antimutagenic activity, besides the modulation of the immune system, might be involved in the anticarcinogenic action of A. blazei. To investigate the possible antimutagenic effect of A. blazei in vivo, we evaluated its effect on clastogenicity induced by cyclophosphamide (CP) in mice, using the micronucleus test in bone marrow (MNPCE) and in peripheral blood (MNRET). Male Swiss mice were treated with CP (25 or 50mg/kg i.p.) or with CP plus mushroom solution at three different temperatures: 4, 21, and 60 degrees C. Aqueous solution of a mixture from various lineages of the mushroom inhibited induction of micronuclei by CP in bone marrow and in peripheral blood of mice. In contrast to the mixture of lineages, a single isolated lineage did not lead to a reduction of CP-induced MN frequencies in either bone marrow or blood cells of mice. The results suggest that under certain circumstances these mushrooms exhibit antimutagenic activities that might contribute to an anticarcinogenic effect.


Asunto(s)
Agaricus/química , Antimutagênicos/farmacología , Daño del ADN/efectos de los fármacos , Extractos Vegetales/farmacología , Animales , Células de la Médula Ósea/efectos de los fármacos , Células de la Médula Ósea/patología , Ciclofosfamida/toxicidad , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Ratones , Pruebas de Micronúcleos , Mutágenos/toxicidad , Reticulocitos/efectos de los fármacos , Reticulocitos/patología
9.
Mutat Res ; 496(1-2): 23-32, 2001 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-11551477

RESUMEN

We evaluated the antimutagenic effect of Letinula edodes (Berk.) Pegler (Shiitake) on the frequency of micronuclei in mice treated with N-ethyl-N-nitrosourea (ENU) or cyclophosphamide (CP). Mice were orally (gavage) pretreated for 15 consecutive days with solutions of Shiitake (0.6 ml per day, gavage) prepared at three different temperatures: 4, 21 (RT), and 60 degrees C. Then, the animals were intraperitoneally injected on day 15 with CP (25 or 50mg/kg) or ENU (50 mg/kg) and killed 24 or 48 h after treatment for evaluation of micronucleated polychromatic erythrocytes (MNPCEs) in bone marrow and micronucleated reticulocytes (MNRETs). A mixture of L. edodes lineages (LE 95/016, 96/14, 96/17, 96/22, 96/23, 97/27, and 97/28) significantly decreased the frequencies of MNPCEs and MNRETs induced by CP (25 and 50mg/kg). When a single lineage from the mixture (LE 96/17) was tested we also found a significant reduction in the frequencies of MNPCEs and MNRETs induced by both CP or ENU (50mg/kg). The comet assay was also performed 3h after ENU treatment using mice pretreated with the single lineage (LE 96/17) of L. edodes. The results showed a high degree of variability with some indications of an antigenotoxic effect. Taken together, our data show that solutions from Shiitake inhibit in vivo mutagenicity of CP and ENU.


Asunto(s)
Antimutagênicos/farmacología , Daño del ADN/efectos de los fármacos , Extractos Vegetales/farmacología , Hongos Shiitake/química , Animales , Células de la Médula Ósea/efectos de los fármacos , Células de la Médula Ósea/patología , Recuento de Células , Ensayo Cometa , Ciclofosfamida/toxicidad , Eritrocitos/efectos de los fármacos , Etilnitrosourea/toxicidad , Masculino , Ratones , Pruebas de Micronúcleos , Mutágenos/toxicidad , Reticulocitos/efectos de los fármacos , Reticulocitos/patología , Temperatura
10.
Food Chem Toxicol ; 41(4): 555-60, 2003 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-12615128

RESUMEN

This study was performed to evaluate the efficiency of four different lineages (95/01, L1, 96/22 and JABK) of Lentinula edodes (BERK.) Pegler mushroom (shiitake) for inhibiting the N-ethyl-N-nitrosourea (ENU) clastogenicity in vivo. Male Swiss mice (10 animals/group) were treated during 15 consecutive days with dried mushroom added to basal diet under three different concentrations (1, 5 and 10%). At day 15, mice were intraperitoneally injected with ENU (50 mg/kg body weight) and sacrificed 24 h later for evaluation of micronucleated bone marrow polychromatic erythrocytes (MNPCE). Negative and positive controls (10 animals each), receiving basal diet and saline or ENU ip injection, respectively, were also evaluated. Results showed that pretreatments with diets containing the lineages 95/01, L1 and 96/22 reduce the frequencies of MNPCE induced by ENU. The absence of an antimutagenic activity for the lineage JABK might be related to intrinsic differences among the lineages such as biochemical composition. Taken together, our data show that the differences in protective activities of the mushrooms need to be clarified in further studies and the mechanisms for such activities need to be investigated.


Asunto(s)
Antimutagênicos/farmacología , Hongos Shiitake/química , Animales , Antimutagênicos/aislamiento & purificación , Peso Corporal/efectos de los fármacos , Médula Ósea/efectos de los fármacos , Dieta , Relación Dosis-Respuesta a Droga , Ingestión de Alimentos/efectos de los fármacos , Eritrocitos/efectos de los fármacos , Eritrocitos/ultraestructura , Etilnitrosourea/toxicidad , Masculino , Ratones , Pruebas de Micronúcleos , Mutágenos/toxicidad , Fenotipo , Hongos Shiitake/genética , Especificidad de la Especie
11.
Rhinology ; 19(1): 35-9, 1981 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-7232997

RESUMEN

After an eight years experience performing an incision in the free border of the gum (the Neumann's incision) to approach the maxillary sinus - the first written communication had been six years before (Rev. Brasil. Oto-Rino-Laring., 40:398, 1974) - the authors describe the details of the technique justifying also their enthusiasm for its almost exclusive use now a days.


Asunto(s)
Encía/cirugía , Seno Maxilar/cirugía , Humanos , Métodos , Complicaciones Posoperatorias
13.
Reprod Domest Anim ; 42(2): 214-7, 2007 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17348981

RESUMEN

The aim of this study was to determine the period of genital tubercle (GT) migration using ultrasonography in Morada Nova sheep foetuses (n = 117) from natural mating (NM) and frozen embryo transfer (ET) to determine the window when foetal sexing can be determined. The examinations were performed using transrectal ultrasonography with a dual-frequency linear transducer (6.0 and 8.0 MHz) from day 30-54 of pregnancy at 48-h intervals. The period of GT migration of foetuses produced by NM varied from 36 to 46 days of pregnancy, resulting in an average of 39.5 +/- 2.9 days. For foetuses derived from ET, GT migration varied from 42 to 52 days of pregnancy with an average of 48.5 +/- 3.3 days, being possible the GT of foetuses from ET start to migrate 96 h later even if they are of the same gender. Migration of the GT occurred earlier (p < 0.05) in foetuses produced by NM and sexing accuracy for triplet pregnancies (77.8%) was significantly inferior (p < 0.05) to single (100%) and twin (92.9%) pregnancies for foetuses derived by NM. The results allow one to conclude that foetal sexing can be done from the 50th day onwards in foetuses produced by NM and from the 55th day onwards in foetuses derived from ET, and that multiple pregnancies compromise the sexing accuracy by ultrasonography.


Asunto(s)
Análisis para Determinación del Sexo/veterinaria , Ovinos/embriología , Ultrasonografía Prenatal/veterinaria , Animales , Transferencia de Embrión/veterinaria , Femenino , Tamaño de la Camada , Embarazo , Análisis para Determinación del Sexo/métodos , Factores de Tiempo , Ultrasonografía Prenatal/métodos
14.
Compendium ; 10(1): 30-4, 1989 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-2598203

RESUMEN

Young children, usually aged between 1 and 3 years, are frequent victims of electric burns of the lip caused by contact with an electric plug or extension cord. In this article, the authors classify the various types of lesions in 19 cases of electric burns of the lip and discuss surgical treatment approaches.


Asunto(s)
Quemaduras por Electricidad/terapia , Labio/lesiones , Niño , Preescolar , Femenino , Humanos , Lactante , Labio/cirugía , Masculino , Estudios Retrospectivos , Férulas (Fijadores)
15.
Eur J Nucl Med ; 22(7): 664-70, 1995 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-7498228

RESUMEN

Technetium-99m hexamethylpropylene amine oxime (HMPAO) labelled leucocytes and indium-111 polyclonal immunoglobulin (IgG) were simultaneously injected into a group of 27 patients routinely referred for the investigation of inflammatory bowel disease (IBD). Ten-minute anterior abdomen and tail on detector views were obtained at 30 min, 4 h and 24 h p.i. of both tracers. The diagnosis of IBD was obtained in all cases by endoscopy with biopsy and/or surgery. Images were blindly evaluated by two experienced observers who only knew of the clinical suspicion of IBD. IBD was confirmed in 20 patients (12 with Crohn's disease and eight with ulcerative colitis). Sensitivity, specificity and accuracy were 100%, 85% and 96% respectively for labelled leucocytes and 70%, 85% and 74% for IgG. Both IgG and leucocyte scans were normal in six out of seven patients in whom a diagnosis of IBD was excluded; the remaining patient, with ischaemic colitis, was falsely positive with both agents. As far as disease extension is concerned, the IgG study localized 27 diseased segments, whereas 49 were seen with the leucocyte study. Eighty-four segments were normal and 25 showed tracer uptake with both agents. Twenty-four were positive only with the leucocyte study and two were positive only with the IgG study. Agreement between the agents was 80.7%. These results confirm that 111In-human polyclonal scintigraphy is less sensitive than 99mTc-HMPAO scintigraphy both for the diagnosis of IBD and in the evaluation of disease extension. Nevertheless, if leucocyte labelling is not available, labelled IgG can be used only for diagnostic purposes.


Asunto(s)
Colitis Ulcerosa/diagnóstico por imagen , Enfermedad de Crohn/diagnóstico por imagen , Inmunoglobulinas Intravenosas , Radioisótopos de Indio , Compuestos de Organotecnecio , Oximas , Adolescente , Adulto , Anciano , Femenino , Humanos , Linfocitos , Masculino , Persona de Mediana Edad , Cintigrafía , Sensibilidad y Especificidad , Exametazima de Tecnecio Tc 99m
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