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1.
Micron ; 183: 103660, 2024 08.
Artigo em Inglês | MEDLINE | ID: mdl-38820862

RESUMO

Tardigrades are invertebrates known to science for over 250 years. Although the ability of some species of tardigrades to form cysts has been reported, little is known about the encystment and internal organisation of the cysts. During cyst formation, contraction of the body affects the internal organs' morphology. The organs are compressed and have a compact appearance. The organisation of the digestive system, associated structures, and the reproductive system are analysed in cysts on indefinite and well-defined encystment periods - up to eleven months. The digestive system of encysted animals was organised into three main parts - a foregut, a midgut, and a hindgut. The presence of digestive system-associated structures, such as buccal glands or muscles, was noted and described. The excretory organs, called Malpighian tubules, open into the zone between the midgut and the hindgut. Furthermore, the oviduct opens into the hindgut. The first analysis of the reproductive system of cysts at the ultrastructural level is presented here, revealing interesting and undescribed aspects related to the physiology. Besides the anatomical and histological examination, the morphology and changes that occur during cyst formation are described.


Assuntos
Sistema Digestório , Tardígrados , Animais , Tardígrados/fisiologia , Sistema Digestório/ultraestrutura , Sistema Digestório/anatomia & histologia , Genitália/anatomia & histologia , Genitália/ultraestrutura , Água Doce , Microscopia Eletrônica de Transmissão , Feminino
2.
J Morphol ; 279(8): 1120-1131, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29732604

RESUMO

The pharaoh cuttlefish, Sepia pharaonis, is an important cephalopod fishery species in southeastern Asia, with understudied reproductive physiology. The present study aimed to investigate the cellular characteristics of epithelial cells found in the nidamental glands (NGs) and accessory NGs (ANGs), as well as the structural connections between these two glands in mature female S. pharaonis. A histological analysis revealed two types of epithelial cells in NGs: Alcian blue-positive, PAS-negative mucosubstance-secreting cells and eosinophilic, PAS-positive granule-secreting cells. Using transmission electron microscopy, three types of epithelial cells were identified: cells with electron-dense granules, cells with electron-lucent granules, and cells with both cilia and microvilli in the apex. Mature ANGs contain an abundance of tubular units composed of epithelial cells resting on a thin layer of basal lamina. Innervated muscle cells are tightly adhered to the basal lamina. In addition, we observed epithelial canalization of ANG tubules penetrating through the connective tissue linking NGs and the walls of the tubules in ANGs, which allows the contents of the ANG tubules to be transported to the NGs. Our results suggest that ANGs participate in the encapsulation of the ova via the same pathway as NGs, which provides an important basis for future studies on the mechanism of protection provided by NGs and ANGs during embryonic development in S. pharaonis.


Assuntos
Genitália/anatomia & histologia , Óvulo/fisiologia , Sepia/anatomia & histologia , Animais , Células Epiteliais/citologia , Feminino , Genitália/citologia , Genitália/ultraestrutura , Sepia/citologia , Sepia/ultraestrutura
3.
Biol Trace Elem Res ; 183(2): 280-287, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28840465

RESUMO

Gold, a heavy yellow-colored metal, is usually found in nature as a metallic element or as salts. This noble metal historically had a reputation as an anti-inflammatory medicine for rheumatoid arthritis, a nervine, and a remedy for nervous disorders, as well as a potential anticancer agent. It has also been used as component in dental restorations and in implant materials. The present study was undertaken to point out histological and ultrastructural effects of gold, administered by intraperitoneal route, in pregnant female reproductive organs (ovary and uterus), in order to clarify its side effects on the reproductive function. Using the transmission electron microscopy (TEM), the ultrastructural investigations of both ultrathin ovarian and uterine sections of treated pregnant rats revealed the existence of numerous heterogeneous clusters with very electron-dense inclusions characterized by various aspects in the lysosomes of granulosa, theca interna cells, and theca externa cells. Degeneration of these tissues, like cell vacuolization, marked expansion of the endoplasmic reticulum, mitochondrial alterations, and necrotic foci, were also highlighted. Moreover, huge phagolysosomes and high numbers of eosinophils as signs of inflammation were also identified especially in endometrial and myometrial cells of gold-treated rats. The ultrastructural investigations of reproductive organ sections of control pregnant rats showed a normal ultrastructural aspect and no loaded lysosomes. These results speculated the toxicity of gold at the used dose. The observed signs of toxicity allowed concluding that the important role of lysosome in the sequestration of this element under an insoluble form in all categories of cells in the studied tissues does not seem to be efficient.


Assuntos
Ouro/farmacologia , Ovário/ultraestrutura , Útero/ultraestrutura , Animais , Endométrio/efeitos dos fármacos , Endométrio/ultraestrutura , Feminino , Genitália/efeitos dos fármacos , Genitália/ultraestrutura , Microscopia Eletrônica de Transmissão , Miométrio/efeitos dos fármacos , Miométrio/ultraestrutura , Ovário/efeitos dos fármacos , Gravidez , Ratos , Útero/efeitos dos fármacos
4.
J Biochem Mol Toxicol ; 17(4): 223-34, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12898646

RESUMO

We explored the reproductive toxicity of argemone oil and its principal alkaloid fraction in transgenic Drosophila melanogaster (hsp70-lacZ) Bg(9). The toxicity of argemone oil has been attributed to two of its physiologically active benzophenanthridine alkaloids, sanguinarine and dihydrosanguinarine. Freshly eclosed first instar larvae of transgenic Drosophila melanogaster were transferred to different concentrations of argemone oil and its alkaloid fraction contaminated food. Virgin flies that eclosed from the contaminated food were pair-mated to look into the effect on reproduction. The study was further extended by investigating hsp70 expression and tissue damage in larval gonads, genital discs, and reproductive organs of adult fly. Our results showed that argemone oil was more cytotoxic than its principal alkaloid fraction. Moreover, it was the male fly that was more affected compared to its opposite number. The accessory glands of male reproductive system of the fly, which did not express hsp70, exhibited severe damage as evidenced by Trypan blue staining. This prompted us to explore the ultrastructural morphology of the gland, which showed acute signs of necrosis in both the cell types as evident by necrotic nuclei, higher vacuolization, and disorganized endoplasmic reticulum, decrease in the number of Golgi vesicles and disorganized, loosely packed filamentous structures in the lumen of the accessory gland, at the higher concentrations of the adulterant. The study showed the reproductive toxicity of argemone oil and its alkaloid fraction in transgenic Drosophila melanogaster and further confirmed the cytoprotective role of hsp70.


Assuntos
Genitália/efeitos dos fármacos , Genitália/patologia , Proteínas de Choque Térmico HSP70/metabolismo , Óleos de Plantas/toxicidade , Alcaloides/toxicidade , Animais , Animais Geneticamente Modificados , Drosophila melanogaster/citologia , Drosophila melanogaster/efeitos dos fármacos , Drosophila melanogaster/fisiologia , Drosophila melanogaster/ultraestrutura , Feminino , Genitália/ultraestrutura , Imuno-Histoquímica , Hibridização In Situ , Masculino , Reprodutibilidade dos Testes , Reprodução/efeitos dos fármacos , Reprodução/fisiologia , Fatores de Tempo , beta-Galactosidase/genética , beta-Galactosidase/metabolismo
5.
Fa Yi Xue Za Zhi ; 17(3): 145-7, 2001 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-12533895

RESUMO

OBJECTIVE: To investigate ultrastructural pathological changes of Heroin-Addicts. METHODS: Heroin-Addicts' central nervous system, endocrine system, immune system and reproductive system in 4 cases are observed by using transmission electron microscope(TEM). RESULTS: The changes of central nervous system are mitochondrion swelling, crista fragmentation and disappear. Endoplasmic reticulum dilation, nervous fibres and cell organelles reduction; mitochondrion swelling, Partial crista fragmentation and endoplasmic reticulum dilation are also found in endocrine system; Lymphocytes reduction, cytoplasm ingredient reduction and dead lymphocytes increase in immune system; in reproductive system, spermatogenic cells and cell organelles are reduced in the male and follicle disappeared in the female. CONCLUSION: Ultra-structural pathological changes of heroin-addicts are presented acute, chronic oxygen deficiency degeneration and necrosis.


Assuntos
Sistema Nervoso Central/ultraestrutura , Sistema Endócrino/ultraestrutura , Genitália/ultraestrutura , Dependência de Heroína/patologia , Sistema Imunitário/ultraestrutura , Feminino , Humanos , Masculino , Microscopia Eletrônica
6.
Mem. Inst. Oswaldo Cruz ; 92(4): 493-8, July-Aug. 1997. ilus, tab
Artigo em Inglês | LILACS | ID: lil-193153

RESUMO

Triatoma brasiliens is considered one of the most important Chagas disease vectors being a wide-spread species in semiarid areas of northeastern Brazil. The species displays distinct chromatic pattern of the cutile in different localities. Four populations were analysed in this study: 1-Caico, Rio Grande do Norte, it will be called the brasiliensis population; 2-Espinosa, Minas Gerais, the melanica population; 3-Petrolina, Pernambuco, the macromelasoma population, and 4-Juazeiro, Bahia, the darker one in overall cutile coloration, the Juazeiro population. In order to differentiate the four populations of T. brasiliensis, a comparative morphological analysis of external genital structures and of eggs were carried out. The analysis of the male genital structures evidenced minor individual stuctural variations that did not correlate with chromatic differences or the geographical origins, emphasizing the importance of examining sufficiently large and representative samples before using minor genital variations for taxonomic diagnosis. By scanning electron microscopy of the egg exochorion, each chromatic population presented a distinct ornamentation pattern. The melancia population differed mainly from the other populations studied since it had about 40.6 per cent, 69.6 per cent and 76.6 per cent more perforations, on each cell exochorion, than the brasiliensis, the Juazeiro and the macromelasoma populations respectively. In the melancia population the perforation layout is also peculiar, with densely distributed perforations over all the egg surface. Morphometric measures of the eggs showed statistically significant differences: the macromelasoma population presented the longest length (2.43 mm) while the shortest was recorded in the brasiliensis population (2.29 mm).


Assuntos
Animais , Genitália/ultraestrutura , Óvulo/ultraestrutura , Triatoma/ultraestrutura , Microscopia Eletrônica de Varredura/instrumentação
7.
Rev. chil. anat ; 15(2): 159-63, 1997. ilus, tab
Artigo em Inglês | LILACS | ID: lil-211920

RESUMO

Las alteraciones morfológicas de la glándula de coagulación de las ratas vasectomizadas, fueron observadas utilizando microscopía de luz y microscopía electrónica de transmisión. Los resultados demostraron disminución en la altura del epitelio secretor. Observaciones ultraestructurales mostraron atrofia de las cisternas del retículo endoplasmático granular


Assuntos
Animais , Ratos , Retículo Endoplasmático Rugoso/ultraestrutura , Epididimo/ultraestrutura , Genitália/ultraestrutura , Vasectomia , Período Pós-Operatório
8.
Nihon Naibunpi Gakkai Zasshi ; 66(3): 175-81, 1990 Mar 20.
Artigo em Japonês | MEDLINE | ID: mdl-2347420

RESUMO

We report a 17 year old patient with mixed gonadal dysgenesis (MGD) raised as a female. The patient had undergone amputation of the phallus at 10 months of age and showed short and masculinized characteristics with ambiguous external genitalia. Abdominal exploration revealed a hypoplastic uterus with a fallopian tube and streak gonad on the right side and a poorly developed testis and epididymis with vas deferens on the left side. Following chromosomal analysis, the cultured peripheral lymphocytes and bone marrow cells showed 45,X in karyotype. Although the mosaicism of 45,X/46,X+mar was revealed by both G- and Q-banding methods in the cultured skin fibroblasts and the cells of various gonadal organs examined, the rate of 45,X karyotype was high (77-97%) in the cells of each organ tissue. Endocrine examinations showed plasma testosterone levels to be slightly higher than those of a normal female. The response of plasma testosterone and estradiol to HCG was low. Hypergonadotropic hypogonadism was revealed.


Assuntos
Disgenesia Gonadal Mista/genética , Disgenesia Gonadal/genética , Adolescente , Medula Óssea/ultraestrutura , Feminino , Fibroblastos/ultraestrutura , Genitália/ultraestrutura , Humanos , Cariotipagem , Linfócitos/ultraestrutura , Mosaicismo , Pele/ultraestrutura
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