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1.
Microsc Res Tech ; 86(2): 208-215, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36285356

RESUMO

The current study aimed to investigate the ultrastructure of the retinal photoreceptors of the African catfish and to demonstrate their adaptation to nocturnal or diurnal visions or by the two ways. The eyes of eight adult catfish were collected during the daytime, and the retinae were separated and examined by light and transmission electron microscopy. The photoreceptors' layer appeared in contact with the retina's pigmented epithelium. Two photoreceptors were detected in cones and hidden rods. Cones predominate in light-adapted retinae. The outer segments of cones appeared between the retinal pigmented epithelium protrusions, which indicates the movement of melanosomes away from the photoreceptors as a retinomotor response of the catfish. The two types of retinal tapetum were in between cones. The first type, the cored granules, were large, spherical, and had black peripheral parts and central lucent parts, and contained some granules. The second type was Guanine crystallites of tapetum lucidum, which were small electron-lucent, and their shape varied from spherical to rectangular. Melanosomes vary in shape from spherical to elliptical. The Müller cells were darkly stained elongated cells that measured about 5.5-8.5 µm in length and 2.2-2.5 µm in width, and their microvilli appeared between the inner segments of the rods and cones. Müller cell processes were extended from the photoreceptor layer to the inner limiting membrane. Zonula occludentes appeared between the Müller cell processes and the internal segment of the rods and cones. African catfish have eyes which are adapted not only for nocturnal but also for daytime light.


Assuntos
Peixes-Gato , Animais , Retina/ultraestrutura , Células Fotorreceptoras Retinianas Bastonetes/ultraestrutura , Células Fotorreceptoras Retinianas Cones/ultraestrutura
2.
Microsc Res Tech ; 86(8): 955-965, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37265363

RESUMO

The purpose of this study was to demonstrate a relationship between the microstructure and measurements of Egyptian buffalo hair and age. The buffalo studied ranged in age from young to premature to adult (3-8 months, 1.5-3, 4-6, and 8-10 years). The hair was collected from the animals' withers. Cuticle elements were examined using scanning electron microscopy (SEM), light microscopy, and energy-dispersive X-ray (EDX) analysis. Hair shaft diameter increased with age, according to SEM and light microscopy measurements. The values of shaft diameter obtained by SEM of the same animal were 64%-67% of the values obtained by light microscopy due to shrinkage of the hair during the drying process. Additional microscopy measurements revealed that the width of the cortex and medulla increased with age, while the width of the cuticle decreased slightly. The medulla index of four different age groups ranged from 0.56 to 0.61 µm. The average distance between successive scale values increased from 4.83 µm in the young group to 8.86 µm between the ages of 8 and 10 years. The scale pattern had a distinct personality at each stage of age. The hair medulla was in the center and consisted of a mesh-like structure with large pores divided into smaller pores by septa. The cortex was a bundle of fibers that wrapped around the medulla. Light microscopy revealed small oval granules and large streak-like granules in the cortex. EDX spectra revealed that carbon, oxygen, and nitrogen were shown to be more abundant in all age groups of buffalo. In buffalo hair, oxygen was the second most abundant element after carbon. The carbon mass in the examined samples decreased slightly with age (42.31%, 39.18%, 38.88%, and 38.49%), while oxygen increased with age. We concluded that hair measurements varied with age, scale microstructure, and elements, so we estimated buffalo animals' ages up to 10 years. HIGHLIGHTS: The goal was to show a link between the microstructure and measurements of Egyptian buffalo hair and age. Hair shaft diameter increased with age, according to scanning electron microscopy (SEM) and light microscopy measurements. The hair shaft diameter obtained by light microscopy was higher than that obtained by scanning electron microscopy of the same animal; we hypothesized that the difference in hair shaft diameter measured by light microscopy and scanning electron microscopy of the same animal was due to the shrinkage of the hair during the drying process. The width of the cortex and medulla increased with age, while the width of the cuticle decreased slightly. The average distance between successive scale values increased from 4.83 µm in the young group to 8.86 µm between 8 and 10 years old. At each stage of age, the scale pattern had a distinct personality. Carbon, oxygen, and nitrogen were found to be more abundant in the hair of buffalo of all ages and were detected using energy-dispersive X-ray (EDX) spectra. After carbon, oxygen was the second most abundant element in buffalo hair. The carbon mass in the samples studied decreased slightly with age, while the oxygen mass increased. Hair measurements varied according to age, scale microstructure, and elements.


Assuntos
Elétrons , Cabelo , Animais , Microscopia Eletrônica de Varredura , Raios X , Egito , Cabelo/ultraestrutura
3.
Cardiovasc Toxicol ; 18(1): 63-75, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28593443

RESUMO

To assess the influence of diclofenac sodium (DIC) treatment on tilmicosin (TIL) prompted cardiotoxicity, forty albino rats were randomly divided into four equal groups: control, TIL group (single subcutaneous injection of 75 mg/kg BW tilmicosin phosphate 30%), TIL + DIC group (single subcutaneous injection of tilmicosin phosphate 30% and then injection intramuscularly of 13.5 mg/kg BW/day for 6 days diclofenac sodium) and DIC group (intramuscular injection of 13.5 mg/kg BW/day diclofenac sodium for 6 days). Creatine kinase-MB, lactate dehydrogenase, aspartate aminotransferase, alanine aminotransferase, urea and creatinine significantly elevated in all treated groups, but markedly in TIL + DIC group serum. Lipid peroxidation significantly increased, and reduced glutathione significantly decreased in tissues of all groups. Several histopathological alterations were noticed in heart, liver, kidneys and lungs of all treated groups, particularly TIL + DIC group. Ultrastructurally, myocardium of TIL and TIL + DIC groups showed characteristic changes for myocardial apoptosis and degeneration. Significant differences were detected in area percentage of caspase-3 protein expression and bcl-2 immunoreactivity in cardiomyocytes, particularly in TIL + DIC group. This study is the first to indicate that one of the possible mechanisms of TIL cardiotoxicity is myocardial apoptosis. DIC amplifies TIL-induced cardiotoxicity besides its hepato-nephrotoxicity.


Assuntos
Diclofenaco/toxicidade , Cardiopatias/induzido quimicamente , Miócitos Cardíacos/efeitos dos fármacos , Tilosina/análogos & derivados , Animais , Apoptose/efeitos dos fármacos , Biomarcadores/sangue , Cardiotoxicidade , Caspase 3/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Doença Hepática Induzida por Substâncias e Drogas/patologia , Modelos Animais de Doenças , Cardiopatias/sangue , Cardiopatias/patologia , Nefropatias/induzido quimicamente , Nefropatias/patologia , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/ultraestrutura , Estresse Oxidativo/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Edema Pulmonar/induzido quimicamente , Edema Pulmonar/patologia , Edema Pulmonar/prevenção & controle , Ratos
4.
Int J Vet Sci Med ; 4(1): 11-16, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30255033

RESUMO

Zinc phosphide (Zn3P2) is a widely used rodenticide which has the potential to cause high mortality if ingested. The present study was designed in order to explore the hepatic injury in broiler chicks that were acutely intoxicated with Zn3P2. For this purpose, a total number of 12 broiler Saso chicks were divided into two equal groups. Birds of the first group were exposed to 300 ppm Zn3P2 via food. Hepatic damage of intoxicated birds was evaluated biochemically and histologically using the transmission electron microscope and subsequently compared with another healthy non-treated controls (second group). The serum activity of aspartate aminotransferase (AST) was significantly higher in those poisoned with Zn3P2, While, activities of both Alanine aminotransferase (ALT) and Alkaline phosphatase (ALP), as well as, zinc concentration of hepatic tissue did not represented a significant difference between treated and control birds. Histological examination revealed presence of numerous heterogenic shaped mitochondria in hepatocytes of non-treated birds. Glycogen deposits were also scattered in the form of large electron dense deposits. Kupffer cell was irregular in shape and had numerous pseudopods often projected into sinusoidal lumen. In hepatic cells of intoxicated birds, mitochondrial swelling with cristolysis, few glycogen deposits, vacuoles in the cytoplasm and shrunken darkly stained nuclei are the major ultra-structural changes which were detected. It was concluded that the mitochondria could be one of the main target in hepatocytes for the toxic effect of Zn3P2 in broiler chicks.

5.
Vet Res Commun ; 36(2): 129-38, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22382528

RESUMO

The ostrich foot has four toepads, two on the 3rd digit, one on the 4th digit and one at metatarso-phalangeal joint. Previous studies have not detailed the histo-morphological structure of these toepads. In this study, we have described the macroscopic and microscopic structures of the toepad of ostrich (Struthio camelus). Numerous papillae with different direction, length and thickness have been observed grossly on the ventral surface of each toepad. Histological examinations have revealed that the epidermis of the ostrich toepad, similar to other digitigrades, consists of an outer stratum corneum and an inner stratum germinativum (which is subdivided into basal, intermediate and transitional layers). The stratum corneum has several layers of flattened horny cells. The nuclei of basal cells have several mitotic figures. The cytoplasm of the stratum germinativum cells has multiple lipid droplets and multigranular bodies (in transitional cells only). Scanning electron microscopic examination revealed presence of collagen fibers in mid and deep dermis of each toepad. These fibers run parallel and connect to each other by very thin fibrils which are branched, crossed with each other in an oblique direction. Such arrangement of these collagen fibers, thin fibrils and presence of digital cushion are likely to be responsible for the protection of the underlying soft tissues and absorption of concussion.


Assuntos
Pele/ultraestrutura , Struthioniformes/anatomia & histologia , Dedos do Pé/anatomia & histologia , Animais
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