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1.
Phys Chem Chem Phys ; 24(25): 15406-15415, 2022 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-35704895

RESUMO

Normal-to-malignant transformation is a poorly understood process associated with cellular biomechanical properties. These are strongly dependent on the dynamical behaviour of water, known to play a fundamental role in normal cellular activity and in the maintenance of the three-dimensional architecture of the tissue and the functional state of biopolymers. In this study, quasi-elastic neutron scattering was used to probe the dynamical behaviour of water in human cancer specimens and their respective surrounding normal tissue from breast and tongue, as an innovative approach for identifying particular features of malignancy. This methodology has been successfully used by the authors in human cells and was the first study of human tissues by neutron scattering techniques. A larger flexibility was observed for breast versus tongue tissues. Additionally, different dynamics were found for malignant and non-malignant specimens, depending on the tissue: higher plasticity for breast invasive cancer versus the normal, and an opposite effect for tongue. The data were interpreted in the light of two different water populations within the samples: one displaying bulk-like dynamics (extracellular and intracellular/cytoplasmic) and another with constrained flexibility (extracellular/interstitial and intracellular/hydration layers).


Assuntos
Neoplasias , Água , Humanos , Difração de Nêutrons/métodos , Nêutrons
2.
Eur J Nucl Med Mol Imaging ; 49(7): 2364-2376, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35102436

RESUMO

A clear margin is an important prognostic factor for most solid tumours treated by surgery. Intraoperative fluorescence imaging using exogenous tumour-specific fluorescent agents has shown particular benefit in improving complete resection of tumour tissue. However, signal processing for fluorescence imaging is complex, and fluorescence signal intensity does not always perfectly correlate with tumour location. Raman spectroscopy has the capacity to accurately differentiate between malignant and healthy tissue based on their molecular composition. In Raman spectroscopy, specificity is uniquely high, but signal intensity is weak and Raman measurements are mainly performed in a point-wise manner on microscopic tissue volumes, making whole-field assessment temporally unfeasible. In this review, we describe the state-of-the-art of both optical techniques, paying special attention to the combined intraoperative application of fluorescence imaging and Raman spectroscopy in current clinical research. We demonstrate how these techniques are complementary and address the technical challenges that have traditionally led them to be considered mutually exclusive for clinical implementation. Finally, we present a novel strategy that exploits the optimal characteristics of both modalities to facilitate resection with clear surgical margins.


Assuntos
Neoplasias , Análise Espectral Raman , Humanos , Margens de Excisão , Neoplasias/diagnóstico por imagem , Neoplasias/cirurgia , Imagem Óptica/métodos
3.
Arq. bras. med. vet. zootec ; 68(2): 415-421, mar.-abr. 2016. tab, graf
Artigo em Inglês | LILACS | ID: lil-779797

RESUMO

In modern pig farming, the search for systems that promote environmental quality and welfare is an important issue. In this sense, the present study evaluated the effects of environmental enrichment on the performance and behavior of piglets. In a completely randomized block design, 32 piglets (7.43kg mean weight), weaned at 28 days of age, were distributed into four treatments (control without enrichment, environmental enrichment with wood shavings as bedding; environmental enrichment with hanging toys and environmental enrichment with wood shavings + hanging toys). Four repetitions were performed for each treatment, with two animals per experimental unit. The instant scan sampling technique was used to record the behavior of each piglet for 20h. Animals receiving environmental enrichment with wood shavings + hanging toys were heavier at 70 days (P=0.02), exhibited higher total and daily weight gain (P=0.04 and P=0.02, respectively) and better feed conversion (P=0.02). Environmental enrichment increased the interaction of animals with the environment, allowing them to exhibit natural behaviors.


Na suinocultura moderna, a busca de sistemas que promovam a qualidade e o bem-estar do meio ambiente é uma questão importante. Nesse sentido, o presente estudo avaliou os efeitos do enriquecimento ambiental sobre o desempenho e o comportamento de leitões. Em um delineamento em blocos ao acaso, 32 leitões (7,43kg de peso médio), desmamados aos 28 dias de idade, foram distribuídos em quatro tratamentos (controle sem enriquecimento, enriquecimento ambiental com cama de maravalha, enriquecimento com móbiles e cama + móbiles). Quatro repetições foram realizadas para cada tratamento, com dois animais por unidade experimental. A técnica de amostragem de varredura instantânea foi usada para registrar o comportamento de cada leitão, totalizando 20h. Os animais que receberam enriquecimento ambiental com cama + móbiles foram mais pesados aos 70 dias (P = 0,02), apresentaram maior ganho de peso total e diário (P = 0,04 e P = 0,02, respectivamente) e melhor conversão alimentar (P = 0,02). O enriquecimento ambiental aumentou a interação dos animais com o meio ambiente, o que lhes permite exibir comportamentos típicos.


Assuntos
Animais , Bem-Estar do Animal , Comportamento Animal , Suínos , Desmame , Criação de Animais Domésticos , Meio Ambiente
4.
Reprod Domest Anim ; 48(1): 160-4, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22734461

RESUMO

Electroejaculation is a technique that can be used to collect semen from canines, but its use with this group of animals is restricted by low success rate and low semen quality. Here, we evaluated whether pharmacological and sexual sensory stimuli, which may affect ejaculation, can increase electroejaculation efficiency and improve ejaculate quality. We worked with 20 dogs of mixed breed weighing between 5.3 and 22.2 kg, divided into two groups. Both groups were exposed to a spayed female for 10 min, but in the second group, the same spayed female had her vagina impregnated with methyl 4-hydroxybenzoate synthetic pheromone for 10 min and after receiving dinoprost tromethamine IM, 0.1 mg/kg. After stimulation, all dogs were chemically restrained with ketamine, 8 mg/kg, IM; and xylazine, 1 mg/kg, IM, and subjected to electroejaculation protocol. We obtained 100% of antegrade ejaculate in treatments when the spayed female had her vagina impregnated with pheromone and 80% when she did not. Sperm motility was significantly different (p < 0.05) between controls and the test group (10.1 ± 4.5 and 43.0 ± 8.3, respectively). We concluded that the adopted electroejaculation protocol was efficient and that the PGF2α associated with sexual sensory stimulation can improve semen quality in dogs undergoing the procedure.


Assuntos
Dinoprosta/análogos & derivados , Cães/fisiologia , Ejaculação/fisiologia , Estimulação Elétrica/métodos , Parabenos/farmacologia , Espermatozoides/fisiologia , Animais , Dinoprosta/administração & dosagem , Dinoprosta/farmacologia , Quimioterapia Combinada , Masculino , Parabenos/administração & dosagem , Comportamento Sexual Animal , Motilidade dos Espermatozoides/fisiologia
5.
Braz. j. morphol. sci ; 30(1): 43-48, 2013. ilus
Artigo em Inglês | LILACS | ID: lil-699330

RESUMO

The Renaissance was a period of extensive scientific and cultural production, which occurred between the fourteenth and sixteenth centuries. One of the exponents of this artistic period was the poet, architect, sculptor and painter Michelangelo Buonarroti, who was born and lived in Italy between 1475 and 1564. Among his best known artworks are the frescoes painted on the Sistine Chapel ceiling. Currently, there is discussion if the paintings are only representations made from the sacred guidance of the church at the time, or if there are other meanings hidden in the images. From this context, we analyzed studies that associated the frescoes painted on the Sistine Chapel ceiling with anatomical structures hidden in the images, taking into account their significance, importance, and if these structures are not simply an imaginative interpretation of the researchers. This study was performed aiming to complement the work published by Ellwanger, Mohr and Campos (2012) in this journal.


Assuntos
Humanos , Masculino , Feminino , Anatomia Artística , Ilustração Médica , Medicina nas Artes , Pinturas
6.
Braz. j. morphol. sci ; 29(3): 123-124, jul.-sept. 2012.
Artigo em Inglês | LILACS | ID: lil-665196

RESUMO

The palatoglossus muscle is classically described as an extrinsic muscle of the tongue. However, this descriptionis not consensus among the researchers, is one that sometimes it is not considered a muscle of the tongue.Thus, the objective of this study is to discuss some neuroanatomical aspects of palatoglossus muscle that mayhelp explain this aspect. Furthermore, this study shall be useful for clinicians, surgeons and academics thatmanipulate and keep particular interest for this anatomical site.


Assuntos
Língua/anatomia & histologia , Músculos Palatinos/inervação , Palato/anatomia & histologia , Neuroanatomia
7.
Theriogenology ; 77(8): 1686-97, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22341712

RESUMO

Under field conditions the motility of bull semen often has to be estimated under a coverslip on a microscope slide. This study was aimed at determining which combination of fields under coverslips provides measurements of sperm motility that best represent the motility in semen specimens as measured in a specially designed chamber for use in a computer-assisted sperm analyzer (CASA). We measured the motility (percentages motile, progressively motile, and aberrantly motile spermatozoa) in each of four straws of frozen-thawed semen from each of 10 bulls five times, ranging from 5 to 120 minutes after thawing with each bull by straw by time combination yielding one semen specimen. Motility was measured in duplicate in a Hamilton, Thorne IVOS CASA; once in each of 12 fields equally spaced along the equatorial radius of a coverslip (Field 0 at the edge and Field 11 at the center) and once in each of eight equally spaced fields along the equator of a Leja 4 chamber designed for use in a CASA. We used the weighted average motility of all fields in a chamber as gold standard and compared it to the average motility of each the following combinations of fields under the coverslip: all 12 fields, Fields 2 to 4, Fields 2 and four, Field 3 and the center three fields. The concordance correlation coefficient (CCC) was determined between the motility in each combination of fields under coverslips and the chambers as a reproducibility index, which evaluates the agreement between the readings under the coverslips and the gold standard readings in the chambers (n = 187 for each CCC). We performed pairwise comparisons of the CCCs (P < 0.005 for each comparison) and established that the average motility under all 12 fields better reproduced the motility in the chamber than the center three fields or Field 3. The averages of Fields 2 to 4 and Fields 2 and 4 reproduced chamber motility as well as the average of all 12 fields, except for the percentage motile sperm, where the average of all 12 fields was better. Using the average motility of Fields 2 and 4, 50% of estimates fell within 6%, 4% and 3% above or below the percentages motile, progressively motile and aberrantly motile spermatozoa in the Leja 4 chamber, 80% of estimates fell within 12%, 8% and 7% thereof and 95% fell within 23%, 13% and 12% thereof. In conclusion, for the method of spreading semen under a coverslip and the range in motility values used, this study shows that the average of the motility over the 12 fields along the equatorial radius under a coverslip provides the best estimate of the motility of a semen specimen, while the average of Fields 2 and 4 is also suitable for the subjective estimation of motility under field conditions, although the estimated motility is expected to fall within 6% above or below the motility of the specimen in only 50% of semen specimens.


Assuntos
Análise do Sêmen/veterinária , Motilidade dos Espermatozoides , Animais , Bovinos , Masculino , Reprodutibilidade dos Testes , Análise do Sêmen/métodos , Espermatozoides
8.
Hereditas ; 143(2006): 62-7, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17362336

RESUMO

The C-banding pattern and the size and location of the nucleolar organizer regions (NORs) are described for the first time in Brazilian populations of Anopheles (Nyssorhynchus) albitarsis sensu lato. C-banding revealed variation in the size of the centromeric heterochromatic blocks in autosomal chromosomes and in the acrocentric (X) and puntiform (Y) sex chromosomes. Fluorescence in situ hybridization showed that the NORs were located in the pericentromeric region of the sex (XX/XY) chromosomes and that this coincided with the number and location of centromeric constitutive heterochromatin blocks previously revealed by C-banding. The NORs varied in size among the homologues of the three populations. These findings of the populations studied support the hypothesis that the stability of NORs in the A. albitarsis complex is characterized by the presence of clustered and conserved sites in a unique pair of chromosomes.


Assuntos
Anopheles/genética , Cromossomos , Animais , Anopheles/classificação , Brasil , Bandeamento Cromossômico , Hibridização in Situ Fluorescente , Cariotipagem , Metáfase , Cromossomo X , Cromossomo Y
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