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1.
Exp Eye Res ; 238: 109736, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38036216

RESUMO

The objective was to evaluate ocular changes based on sex in steroid-induced glaucoma models in rats comparing healthy controls, over 24 weeks follow-up. Eighty-nine Long-Evans rats (38 males and 51 females) with steroid-induced glaucoma were analysed. Two steroid-induced glaucoma models were generated by injecting poly-co-lactic-glycolic acid microspheres loaded with dexamethasone (MMDEX model) and dexamethasone-fibronectin (MMDEXAFIBRO model) into the ocular anterior chamber. Intraocular pressure was measured by rebound tonometer Tonolab®. Neuroretinal function was analysed using dark- and light-adapted electroretinography (Roland consult® RETIanimal ERG), and structure was analysed using optical coherence tomography (OCT Spectralis, Heidelberg® Engineering) using Retina Posterior Pole, Retinal Nerve Fibre Layer and Ganglion Cell Layer protocols over 24 weeks. Males showed statistically (p < 0.05) higher intraocular pressure measurements. In both sexes and models neuroretinal thickness tended to decrease over time. In the MMDEX model, males showed higher IOP values and greatest percentage thickness loss in the Ganglion Cell Layer (p = 0.015). Females receiving MMDEXAFIBRO experienced large fluctuations in thickness, a higher percentage loss (on average) in Retina Posterior Pole (p = 0.035), Retinal Nerve Fibre Layer and Ganglion Cell Layer than aged-matched males, and the highest thickness loss rate by mmHg. Although no difference was found by sex in dark- and light-adapted electroretinography, increased amplitude in photopic negative response was found in MMDEX males and MMDEXAFIBRO females at 12 weeks. Although both glaucoma models used dexamethasone, different intraocular pressure and neuroretinal changes were observed depending on sex and other influential cofactors (fibronectin). Both sex and the induced glaucoma model influenced neuroretinal degeneration.


Assuntos
Fibronectinas , Glaucoma , Masculino , Feminino , Ratos , Animais , Seguimentos , Células Ganglionares da Retina , Ratos Long-Evans , Pressão Intraocular , Tomografia de Coerência Óptica/métodos , Dexametasona/toxicidade
2.
Arch Soc Esp Oftalmol (Engl Ed) ; 99(4): 145-151, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38216050

RESUMO

INTRODUCTION: The aim of this work is to evaluate the usefulness of the study of the ganglion cell complex of the macula using the OCT technique to estimate the progression of glaucoma according to its severity. MATERIAL AND METHODS: This is a retrospective cross-sectional study. It includes 205 eyes of 131 patients with glaucoma or ocular hypertension followed for a mean of 5.7 years. The parameters and rates of three tests have been analyzed using the progression software of each instrument: visual field, optical coherence tomography (OCT) in the ganglion cell complex of the macula and in the nerve fiber layer of the optic nerve. The results of each test, the concordance between them and how they differ according to severity stage have been evaluated. RESULTS: Visual field classifies more cases of progression in moderate-advanced glaucoma, while in mild glaucoma its capacity is limited. Optic nerve fiber layer OCT classifies more cases of progression in mild glaucoma than in moderate-advanced glaucoma, as it is artifacted by the floor effect. OCT of the macular ganglion cell complex is the test that classifies more cases of progression and has the highest agreement with visual field, regardless of severity. CONCLUSION: In both mild and moderate-advanced glaucoma, OCT of the macula ganglion cell complex may be a better biomarker of progression than OCT of the macula ganglion cell complex.


Assuntos
Glaucoma , Tomografia de Coerência Óptica , Humanos , Tomografia de Coerência Óptica/métodos , Estudos Retrospectivos , Estudos Transversais , Pressão Intraocular , Células Ganglionares da Retina
3.
Artigo em Inglês | MEDLINE | ID: mdl-38901607

RESUMO

Trochleitis is clinically and/or radiologically evidenced inflammation of the trochlea or orbital pulley. Clinically it is characterized by pain and hypersensitivity in the superomedial orbital angle, which is increased or triggered by direct palpation of the area and/or eye movements. During the REM (rapid eye movements) phase of sleep, patients with trochleitis suffer from nocturnal micro-awakenings that impede their rest, and pain is often associated with visual symptoms (diplopia or Brown's syndrome). The lack of common guidelines for diagnosis and treatment of this disease, its low prevalence and the lack of knowledge of the different entities associated with trochlear pain, leads to underdiagnosis or misdiagnosis. It is essential to know the characteristics of this pathology and to diagnose it correctly, differentiating it from other trochlear pain entities, in order to be able to carry out an adequate therapeutic and prognostic approach. The lack of consensus on the therapeutic protocol means that various treatments are used, in different order and often with a combination of several without a firm scientific basis. This comprehensive review of previous studies concludes that nonsteroidal anti-inflammatory drugs (NSAIDs) achieve an overall complete cure rate of 77%, although this rate decreases to 30% in case of motility restriction or diplopia. Intratrochlear corticosteroid injection achieves an overall complete cure rate of 86%, even in the worst prognosis trochleitis, being the only effective option in NSAID-refractory trochleitis and currently being questioned as the first treatment option.

4.
Meat Sci ; 76(3): 574-82, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22061003

RESUMO

Dry-cured ham, "Protected Designation of Origin (PDO)" Teruel, is a high quality meat product processed using a traditional dry-curing procedure. The objective of this paper was to study the microstructure of the Biceps femoris and Semimembranosus muscles during "PDO Teruel" dry-cured ham processing using electron microscopy techniques (Cryo-SEM, SEM and TEM). The Semimembranosus and Biceps femoris muscles from raw ham show the typical structure of muscle tissue in meat. The muscle fibres appear firmly attached to one another by the endomysial connective tissue; the myofibrils inside the cells are strongly attached to each other and to the sarcolemma. In raw ham, the typical structural elements that constitute the sarcomere can be observed by TEM. Important microstructural changes are observed following salting; reflected in the fact that the Z-disks inside the myofibrils are no longer in line and there is important degradation of the cell membranes in this stage. At the end of the process, an accumulation of solutes, which could be products from proteolysis occurring mainly in the last stage of ripening, could be observed in both muscles. Thus the proteolysis and dehydratation phenomena that take place during "PDO Teruel" dry-cured ham processing occur at an ultrastructural level, and this is the basis to produce a product with the sensory features appreciated by consumers.

5.
Meat Sci ; 74(3): 586-93, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22063063

RESUMO

The aim of this work was to investigate the degradation of the water-soluble and myofibrillar proteins during the production of "PDO Teruel" cured ham using SDS-PAGE, and measurement of proteolytic activities (cathepsins B+L, cathepsin L, cathepsin D), as factors that influence the sensory characteristics of this product. This paper contributes to the specific characterisation of a product included in the European Union list of special quality products. The results showed that water-soluble proteins decrease considerably due to salting out and drainage after salting. The degradation of myofibrillar proteins is more pronounced during the ripening process, particularly in the last four months when the main proteins responsible for the structure of muscular tissue are affected. There is an important residual enzymatic activity for cathepsin B, L and D, which must be a decisive factor in the proteolysis observed during "PDO Teruel" ham processing.

6.
Meat Sci ; 66(4): 823-9, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22061014

RESUMO

This work studied the microstructural degradation of rabbit semimembranosus muscle wrapped with Pteridium aquilinum fern fronds, stored at 4 °C during the first 72 h postmortem. At the microstructural level, practically all the perimysial and endomysial connective tissue was destroyed and a small degradation of the myofibrils could be observed after the first 24 h postmortem; in addition, a degradation of the sarcolemma and the generation of numerous gaps were seen. After 32 h postmortem, tissue fibres were broken, cell membranes were more strongly degraded, and the connections between the sarcolemma and the myofibrils had disappeared. After 72 h postmortem, intercellular connections became degraded inside the muscle bundles and intercellular gaps became larger. The proteolytic activity is attributed to fern endogenous enzymatic activity in addition to the typical endogenous enzymatic activity of meat postmortem.

7.
J Food Sci ; 74(2): S90-6, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19323772

RESUMO

Improving the quality of different fresh-cut fruits by adding natural substances was studied. "Fuji" apples, "Flor de Invierno" pears, and "Piel de Sapo" melons were treated with calcium lactate, N-acetyl-L-cysteine, glutathione, and malic acid and stored for 4 wk at 4 degrees C. Instrumental texture (penetration), microstructure (light microscopy), acidity, soluble solids, color, pectinmethylesterase activity, and microflora were studied. The results showed that the combined treatment reinforced the cell walls strengthening the structure and texture of these fruits and maintained the L* and a* values throughout 4 wk of storage at 4 degrees C. The combination of additives provided low microbial counts in apples until the 4th week and in melons until the 2nd week. So, this combined treatment could be used to extend the shelf life of some fresh-cut fruits while preserving their quality.


Assuntos
Aditivos Alimentares , Frutas/normas , Acetilcisteína/análise , Compostos de Cálcio/análise , Cucurbitaceae , Glutationa/análise , Concentração de Íons de Hidrogênio , Lactatos/análise , Malatos/análise , Malus , Pyrus
8.
J Food Sci ; 73(8): E356-62, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19019106

RESUMO

Quality of rehydrated products is a key aspect linked to rehydration conditions. To assess the effect of rehydration temperature on some quality parameters, experiments at 20 and 70 degrees C were performed with convective dried and freeze-dried Boletus edulis mushrooms. Rehydration characteristics (through Peleg's parameter, k(1), and equilibrium moisture, W(e)), texture (Kramer), and microstructure (Cryo-Scanning Electron Microscopy) were evaluated. Freeze-dried samples absorbed water more quickly and attained higher W(e) values than convective dried ones. Convective dehydrated samples rehydrated at 20 degrees C showed significantly lower textural values (11.9 +/- 3.3 N/g) than those rehydrated at 70 degrees C (15.7 +/- 1.2 N/g). For the freeze-dried Boletus edulis, the textural values also exhibited significant differences, being 8.2 +/- 1.3 and 10.5 +/- 2.3 N/g for 20 and 70 degrees C, respectively. Freeze-dried samples showed a porous structure that allows rehydration to take place mainly at the extracellular level. This explains the fact that, regardless of temperature, freeze-dried mushrooms absorbed water more quickly and reached higher W(e) values than convective dried ones. Whatever the dehydration technique used, rehydration at 70 degrees C produced a structural damage that hindered water absorption; consequently lower W(e) values and higher textural values were attained than when rehydrating at 20 degrees C.


Assuntos
Basidiomycota , Dessecação/métodos , Manipulação de Alimentos/métodos , Conservação de Alimentos/métodos , Água , Basidiomycota/ultraestrutura , Liofilização , Microscopia Eletrônica de Varredura , Temperatura
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