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1.
Micron ; 181: 103625, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38503061

RESUMEN

The sperm ultrastructure of the bean-weevil Spermophagus kuesteri (Bruchinae) was studied to verify the congruence of the new position of the subfamily within Chrysomelidae. The results indicated a positive answer to the question supporting a close relationship between Chrysomelidae and Curculionidae, a finding confirmed also by molecular data. Moreover, the sperm morphology of Divales cinctus, a member of Melyridae (Cleroidea) allowed to confirm the different sperm organization between members of this superfamily and Phytophaga (Chrysomeloidea + Curculionoidea). While studying the spermiogenesis of S. kuesteri, some sperm cysts showed aberrant cells provided with two flagella in the same plasma membrane. These aberrant sperm could be the result, during early spermiogenesis, of irregular processes involving the canal rings between spermatids.

2.
Microsc Res Tech ; 87(6): 1359-1372, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38380559

RESUMEN

Taxonomic data on Coreidae have been fragmented over time and need to be revised. Likewise, data related to the development of germ cells and the features of the male reproductive system, including sperm, will contribute to understanding the biological mechanisms of reproduction and the systematics of its representatives. Aiming to provide these data, we describe the morphology of the male reproductive system and spermatozoa of Leptoglossus zonatus using light and transmission electron microscopies, respectively. Each of the two testes is surrounded by a bright red-pigmented sheath and formed by seven follicles arranged side by side. The two vasa deferentia are filled with individualized sperm, especially in their final portion, which is dilated and curved. After dilation, the vasa deferentia receive the ducts of the accessory glands of mesodermal origin. The other unpaired accessory gland is of ectodermal origin and opens into the ejaculatory duct. Both glandular types are densely coiled and have lumens filled with secreted material. Testicular follicles contain cysts with germ cells at different stages of spermatogenesis, indicating continuous production of gametes throughout adult life. Mature sperm measure around 310 µm long, with a nucleus of 36 µm and a flagellum formed only by an axoneme of 9 + 9 + 2 microtubules and two symmetrical mitochondrial derivatives. Like the sperm of other Heteroptera, the acrosome has a single structure (without perforatorium), there are no accessory bodies in the flagella, and the mitochondrial derivatives are connected to the axonemes, supporting the synapomorphic condition of these characteristics for this suborder of bedbugs. RESEARCH HIGHLIGHTS: The Leptoglossus zonatus sperm are slender and long, about 310 µm in length, and a nucleus 36 µm long. Spermatogenesis occurs throughout adult life and equally in the seven testicular follicles. The centriole adjunct in L. zonatus sperm does not give rise to accessory bodies. The ectodermal gland produces a filamentous secretion, whereas in the ectodermal sac, the secretion is globular.


Asunto(s)
Heterópteros , Animales , Masculino , Heterópteros/anatomía & histología , Semen , Espermatozoides , Genitales Masculinos , Acrosoma
3.
Microsc Res Tech ; 87(6): 1384-1397, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38380818

RESUMEN

Here, we describe for the first time the sperm morphology of Tingidae (Heteroptera). They are small insects presenting lacy patterns on their pronotum and hemielytra and are exclusively phytophagous, with many economically important species. We studied five species of the tribe Tingini (Tinginae): Teleonemia scrupulosa, Vatiga illudens, Gargaphia lunulata, Leptopharsa sp., and Corythucha arcuata. Their spermiogenesis process is similar to other Heteroptera, with some differences in the formation of the centriole adjunct. This structure extends in the anteroposterior spermatid axis, flanking the nucleus, possibly contributing to nucleus remodeling and sperm elongation. The mature sperm of Tingidae is also similar to that of other Heteroptera, with features that corroborate the group's monophyly. Our data support previous results for their sister family, Miridae, which exhibits some characteristics exclusive to this taxon, not present in Tingidae or other Heteroptera. They also support the sister relationship of the genera Gargaphia and Leptopharsa and suggest closer relationship between Vatiga and Corythucha. Overall, this study sheds light on the sperm ultrastructure of Tingidae and provides information for understanding the evolution and diversity of Heteroptera. RESEARCH HIGHLIGHTS: The spermiogenesis process and mature sperm are similar to other Heteroptera The centriole adjunct is derived from a strip of a pericentriolar material extending from the centriole Tingidae and Miridae are distinguishable using sperm morphology.


Asunto(s)
Heterópteros , Semen , Animales , Masculino , Heterópteros/anatomía & histología , Espermatozoides , Espermátides , Espermatogénesis
4.
Arthropod Struct Dev ; 79: 101344, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38412706

RESUMEN

The Trichoptera, holometabolous aquatic insects found worldwide except in Antarctica, exhibit a unique feature in their sperm, which are solely nucleated (eupyrene). Current knowledge on Trichoptera sperm is limited to Old World species. To enhance our understanding of their reproductive biology and contribute to systematic discussions, we describe the male reproductive system and spermatozoa of Smicridea (Rhyacophylax) iguazu Flint, 1983 (Hydropsychidae). This species lacks seminal vesicles, possesses piriform to oval-shaped testes with spermatozoa grouped in apical bundles and dense filamentous material filling other areas. The vasa deferentia are long and a pair of elongated accessory glands displays distinct proximal and distal regions. The relatively short (∼40 µm) spermatozoa are nucleated, aflagellated, and immobile. Further research could explore variations and assess the taxonomic utility of these features for genus identification within Hydropsychidae.


Asunto(s)
Holometabola , Semen , Masculino , Animales , Espermatozoides , Genitales Masculinos/anatomía & histología , Insectos/anatomía & histología
5.
Micron ; 178: 103591, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-38241905

RESUMEN

Changes in harvesting methods in the early 1990s led to Mahanarva fimbriolata becoming the most prevalent pest in sugarcane plantations. Encouraged by the scarcity of research on the reproductive system and spermatology of Auchenorrhyncha, we provide a detailed description of the male reproductive system and spermatozoa of this cercopid. This will not only aid in taxonomic purposes but also help in understanding the reproductive biology of the species. The male reproductive system, spermatozoa, and sperm bundles of M. fimbriolata were investigated using light microscopy. Our results reveal a reproductive system consisting of a pair of testes, each with 36 follicles, two vasa deferentia, two well-developed seminal vesicles, a single pair of accessory glands, and an ejaculatory duct. Here, we also describe and explore the particularities of the formation of secondary sperm bundles, where cells interestingly bind only to the apical region of the spermatostyle. We also propose some possible benefits of this unusual organization for the reproductive success of the species.


Asunto(s)
Hemípteros , Masculino , Animales , Semillas , Espermatozoides , Genitales Masculinos/anatomía & histología , Testículo
6.
Arthropod Struct Dev ; 75: 101287, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37429116

RESUMEN

We describe the ultrastructure of the female reproductive organs of Deronectes moestus (Dytiscidae Hydroporinae). The long spermathecal duct has a simple epithelium lined internally by a thin cuticle and externally by a thick layer of muscle cells. The wide duct lumen contains electron-dense material, among which remnants of extracellular material are visible. This material consists of tubular structures assembled around sperm bundles previously described in the male deferent ducts. The so-called gland, disposed along the spermathecal duct, is a structure with epithelial cells lined by an irregular cuticle bearing a rich system of microvilli. Many mitochondria are visible in the apical cytoplasm of the epithelial cells, and a few spheroidal bodies are close to the basal nuclei. Since the epithelial ultrastructure of the gland suggests it is involved in fluid uptake from the lumen rather than secretory activity, the term gland, coined by other authors to describe this organ, is inappropriate. The spermatheca is a large structure with a complex epithelium showing secretory and duct-forming cells. The lumen of this organ contains sperm with the distinctive ultrastructural features of those described in the male deferent ducts, namely having a mitochondrial matrix with a small crystallized area and electron-dense dots. Because to its overall organization, the spermatheca of D. moestus can be considered a more integrated organ than those in previously studied hydroporine species.


Asunto(s)
Escarabajos , Masculino , Animales , Femenino , Semen , Espermatozoides/ultraestructura , Células Epiteliales , Epitelio/ultraestructura
7.
Microsc Res Tech ; 86(11): 1510-1516, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37365943

RESUMEN

The sperm morphology can provide helpful information about sexual selection, phylogeny, and the evolutionary history of a given animal group. However, there is limited or no knowledge of many taxa, especially those belonging to insects, a vast and highly diverse group. An example is the Miridae, or plant bugs, which belong to the infraorder Cimicomorpha (Heteroptera), where only three out of 17 families have published data on their sperm morphology. Here we described the Miridae sperm structure by analyzing Pycnoderes incurvus sperm under light and transmission electron microscopy. In this species, the spermatozoa were as long and slender as those of most insects. However, the anterior-most region was twisted, a characteristic first reported for Heteroptera. The acrosome was coated with electron-dense material, most likely extra-acrosomal. The centriole adjunct was a notably long, cylindrical and compact structure connecting the nucleus to the flagellar elements, with just clove-like electron-lucent points in cross-section, also features unique to Miridae so far. The flagella exhibited an axoneme of 9 + 9 + 2 microtubules and two symmetrical mitochondrial derivatives. The latter two partially embrace the axoneme, and each exhibits two paracrystalline areas and a bridge connecting it to the axoneme; these are considered Heteroptera synapomorphies that support their monophyly. RESEARCH HIGHLIGHTS: The P. incurvus sperm showed a twisted acrosome, the first reported for Heteroptera. The centriolar adjunct is a sole structure linking the nucleus and flagellum. The flagella presented the synapomorphies supporting Heteroptera monophyly.

8.
Insects ; 13(5)2022 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-35621819

RESUMEN

The sperm ultrastructure of a few representative species of Tenebrionoidea was studied. Two species belong to the Mordellidae (Mordellistena brevicauda and Hoshihananomia sp.), one species to Oedemeridae (Oedemera nobilis), and one species to Tenebrionidae (Accanthopus velikensis). It is confirmed that Mordellidae are characterized by the lowest number of spermatozoa per cyst (up to 64), a number shared with Ripiphoridae. In contrast, in the two other families, up to 512 spermatozoa per cyst are observed, the same number present, for example, in Tenebrionidae. Also, as in the other more derived families of tenebrionoids studied so far, during spermatogenesis in O. nobilis and A. velikensis, sperm nuclei are regularly distributed in two sets at opposite poles of the cysts. On the contrary, the Mordellidae species do not exhibit this peculiar process. However, during spermiogenesis, the bundles of sperm bend to form a loop in their median region, quite evident in the Hoshihananomia sp., characterized by long sperm. This process, which also occurs in Ripiphoridae, probably enables individuals to produce long sperm without an increase in testicular volume. The sperm looping could be a consequence of the asynchronous growth between cyst size and sperm length. The sperm ultrastructure of the Mordellidae species reveals that they can be differentiated from other Tenebrionoidea based on the shape and size of some sperm components, such as the accessory bodies and the mitochondrial derivatives. They also show an uncommon stiff and immotile posterior flagellar region provided with only accessory tubules. These results contribute to a better knowledge of the phylogenetic relationship of the basal families of the large group of Tenebrionoidea.

9.
Rev. ciênc. méd., (Campinas) ; 18(5/6): 235-241, set.-dez. 2009. tab
Artículo en Portugués | LILACS | ID: lil-574540

RESUMEN

Objetivo Verificar as condições periodontais dos pacientes diabéticos. Métodos Participaram do estudo 32 diabéticos tipo 2 não controlados (valor de referência da hemoglobina glicada de 7%) e 45 indivíduos não diabéticos do grupo-controle, dos quais 30 com doença periodontal e 15 saudáveis. Foram verificados os seguintes parâmetros periodontais: profundidade a sondagem, perda de inserção clínica e dentes ausentes. Os dados foram analisados pelo teste Mann Whitney e teste t Student. Resultados Entre os diabéticos, 17 apresentaram periodontite crônica leve; 11, moderada; e 4, avançada; dos não diabéticos, 15 estavam saudáveis; 13, com periodontite crônica leve; 15, com periodontite moderada; e 2, com avançada. Os pacientes diabéticos apresentaram um maior número de dentes ausentes quando comparados aos não diabéticos (p<0,009 e p<0,0000), profundidade a sondagem maior que o grupo saudável (p<0,0000) e menor que o grupo só com doença periodontal (p<0,0009); perda de inserção clínica não apresentou diferença estatística entre os diabéticos e não diabéticos com doença periodontal (p=0,1576), houve diferença apenas em relação ao grupo saudável. Conclusão No presente estudo o grupo com diabetes apresentou maior perda dentária, o que poderia ser resultado de doença periodontal. Novos estudos devem ser conduzidos para esclarecer melhor essa associação


Objective The objective of this study was to determine the periodontal condition of diabetic patients. Methods In the study, 32 type 2 uncontrolled diabetic patients (reference value of hemoglobin of 7%) and 45 nondiabetic controls (30 with periodontal disease and 15 healthy) were evaluated. The following periodontal parameters were verified: periodontal probing depth, clinical attachment loss and missing teeth. The data were analyzed by the Mann Whitney and Student?s t test. Results Among diabetic patients, 17 had mild chronic periodontitis, 11 moderate and 4 severe, while in nondiabetics 15 were healthy, 13 had mild chronic periodontitis, 15 moderate and 2 severe. Diabetic patients had more missing teeth than the nondiabetic groups (p<0.009 and p<0.0000); periodontal disease was worse than that of the healthy group (p<0.0000) but better than that of the group with periodontal disease (p<0.0009); there was no statistically significant difference in clinical attachment loss between diabetic and nondiabetic patients with periodontal disease (p=0.1576); they only differed from the healthy group. Conclusion In this study the group with diabetes had a greater number of missing teeth, which could be the result of periodontal disease. Further studies should be conducted to clarify this association.


Asunto(s)
Humanos , Masculino , Femenino , Adolescente , Adulto , Persona de Mediana Edad , Anciano , Factores de Riesgo , Pérdida de Hueso Alveolar , Diabetes Mellitus , Enfermedades Periodontales
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