983 resultados para scent glands


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The Brindley's glands of Panstrongylus megistus were studied under the antomic, histologic and ultrastructural point of view. These glands located in the insect's methatorax are paired and have an opening near the third parir of the feet. Beside this aperture, ther are evaporation areas. Shape, sixe and aspect of the gland vary according to the feeding status. The glands are composed by a tubular part corresponding to the duct and a sack-like portion corrsponding to the secretory part. By electron microscopy we observed that the basal part of the epithelium has many interdigitations associated with mitochondria. On the apical surface where epicuticular foldings are located an electonlucent space is often seen. The glands are composed of the following elements: 1) superficial epithelial cells, located just below the apical surface foldings; 2) secretory cells; which are long and have an intracellular canalicule which changes according to the functional state of the cell; 3) a collecting duct to the secretory cells and covered with an epicuticle, reaching up to the gland's lumen; and 4) cells around the duct.

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Acini in in the salivary glands of female tick specimens of Amblyomma ajennense unfed at both postnymphal and adult phases, were studied. The salivary glands are consisted by three acini, one agranular and two granular. The agranular acini are directly attached to the anterior portion of the main salivary duct, consisting of cells without valve. A relatively large, clear, central cell occupies most of the alveolar midsection. The central cell is in contact with the acini lumen. Granular acini consist of approximately seven to fourteen cells (type II acini) or seven to sixteen (type III acini). The type II acini have three types of granular cells ("a", "b" and "c") and valve; the type III acini have another three types of granular cells ("d", "e" and "f") also presenting a valve.

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Acini in the salivary glands of unfed male Amblyomma cajennense of different ages, were studied. The salivary glands consist of one agranular and three granular acini types. The agranular acini are directly attached to the medial and anterior portion of the main salivary duct, and to some branches of the secondary ducts. A large, clear, central cell occupies the centre and this cell is in contact with the acinar lumen. There is no valve to the lumen. Granular acini consist of approximately six to fourteen cells (type II acini) or eight to thirteen (type III acini). The type II acini have three types of granular cells ("a", "b" and "c") and a valve: the type III acini have three types of granular cells ("d", "e" and "f" and a valve.

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Opossums (Didelphis marsupialis) captured in intensely urbanized areas of the city of Caracas, Venezuela, were found infected with Trypanosoma cruzi. The developmental cycle of trypomastigote-epimastigote-metacyclic infective trypomastigote, usually occurring in the intestine of the triatomine vector, was taking place in the anal odoriferous glands of the opossums. Material from the glands, inoculated in young, healthy opossums and white mice by different routes, subcutaneously, intraperitoneally, orally, and into the eye, induced T. cruzi infections in all animals. Parasitemia, invasion of cardiac and skeletal muscle, and intracellular multiplication of amastigotes were observed. Inoculation of metacyclics from anal glands, cultured in LIT medium, gave equivalent results. All opossums survived; all mice died. Excreta of opossums may thus transmit Chagas' disease by contamination, even in urban areas where insect vectors are not present.

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There has been an ardent interest in herbivore saliva due to its roles in inducing plant defenses and its impact on herbivore fitness. Two techniques are described that inhibit the secretion of labial saliva from the caterpillar, Helicoverpa zea, during feeding. The methods rely on cauterizing the caterpillar's spinneret, the principal secretory structure of the labial glands, or surgically removing the labial salivary gland. Both methods successfully inhibit secretion of saliva and the principal salivary enzyme glucose oxidase. Caterpillars with inhibited saliva production feed at similar rates as the untreated caterpillars, pupate, and emerge as adults. Glucose oxidase has been suggested to increase the caterpillar's survival through the suppression of inducible anti-herbivore defenses in plants. Tobacco (Nicotiana tabacum) leaves fed on by caterpillars with ablated salivary glands had significantly higher levels of nicotine, an inducible anti-herbivore defense compound of tobacco, than leaves fed upon by caterpillars with intact labial salivary glands. Tomato (Lycopersicon esculentum) leaves fed upon by caterpillars with suppressed salivary secretions showed greatly reduced evidence of hydrogen peroxide formation compared to leaves fed upon by intact caterpillars. These two methods are useful techniques for determining the role that saliva plays in manipulating plant anti-herbivore defenses.

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A survey of the leg exocrine glands in the termite workers of 16 species of the families Kalotermitidae and Termitidae was carried out through scanning electron microscope. Glandular openings were not found in the legs of Anoplotermes sp., Ruptitermes sp. (Apicotermitinae, Termitidae) or Glyptotermes planus (Kalotermitidae), but they are present, spread over the ventral surface of the first, second and third tarsomeres of other Termitidae such as Armitermes euamignathus, Cornitermes cumulans, Nasutitermes coxipoensis, Rhynchotermes nasutissimus, Syntermes nanus, Embiratermes festivellus (Nasutitermitinae), Amitermes beaumonti, Hoplotermes amplus, Microcerotermes sp., Neocapritermes opacus, Orthognathotermes sp., Spinitermes brevicornutus and Termes sp. (Termitinae). The pores are usually isolated but they can also be grouped inside a round depression. The occurrence of leg exocrine glands in the family Termitidae is reported for the first time.

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The glandular system is crucially involved in main aspects of ant social life. The function of glands has been primarily studied in the workers (the non-reproductive individuals in a colony). In contrast, little information is available on queens (the reproductive females in a colony) or males in spite of the obvious functional differences between these castes. Here we report a comparison of the general morphology of the mandibular, propharyngeal and postpharyngeal glands between the three castes of the black ant Lasius niger. The analysis clearly shows that all these cephalic glands differ in relative size between castes and suggests a link between gland structure and its behavioral role in queens, workers and males. In particular, males present a hypertrophied mandibular gland. This is consistent with the fact that these glands might be the source of the sex pheromone in this caste. By contrast, queens exhibited the most developed postpharyngeal glands. This is consistent with the production of particular cues by queens for workers to help them to distinguish between reproductive and non-reproductive females. Finally, the propharyngeal glands were most developed in the worker caste and of similar relative size in males and queens. Their function is still enigmatic.

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Panurginae have a pair of cuticular depressions in the second metasomal tergum, recognized as lateral foveae of the T2. These structures have been used as systematic and taxonomic characters, although their functions are yet unknown. We aimed a morphological analysis at lateral foveae of three species of Panurgillus Moure, 1998: P. vagabundus (Cockerell, 1918), P. reticulatus Schlindwein & Moure, 1998 e P. flavitarsis Schlindwein & Moure, 1998. The study of the external morphology showed that the lateral foveae of the T2 are evident among females, but in males they are undistinguishable or absent. The surface of the foveae is micropunctuated in all species. The histological analysis has shown that the region of the lateral foveae of the T2, of female and male of the three species, presented tegumentar specializations. The inner part showed an evident secretory epithelium recognized as Class I gland. The height of this secretory epithelium was not uniform, although the cellular features are similar independent of sex. We have not found any previous information regarding the presence of glands related to abdominal foveae in Panurginae species.

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Defensive behavior associated with secretions from the prosternal paired glands of the larvae of Heliconius erato phyllis Fabricius (Lepidoptera, Nymphalidae). Our work presents for the first time, the defensive behavior associated with the release of the product of the prosternal paired glands of the larva of Heliconius erato phyllis Fabricius, 1775 (Lepidoptera, Nymphalidae, Heliconiinae). The prosternal glands were first described for larvae of H. erato phyllis. They are formed by two types of glandular structures: the impair gland and the paired glands. The prosternal glands are located within the conical integumentary sac, which in turn is situated on the individual's prosternum. The main goal of this study is to analyze the existence of any secretion from the prosternal paired glands, and check the action mode of this secretion. The methodology used for chemical analysis of the glands included the aeration and, analysis in gas chromatography and gas chromatography-mass spectrometry. The results show that the prosternal glands do not produce volatiles. Bioassays were conducted with simulated and natural attacks and revealed that the prosternal paired glands produce secretions of defense together with silk produced by labials glands as a defense strategy, described for the first time, against ants. The strategy consists in wrapping the ant with silk threads, the entire wrapped object moved to the end of the body, with the aid of the legs and prolegs, and possibly fixed in a nearby place. Evidence for the existence of a conical integumentary sac in larvae of other species and families of Lepidoptera allows us to propose the possibility of occurrence of prosternal paired glands with defensive function in these other groups as well.

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Purpose: Involvement of salivary glands with mucosa-associated lymphoid tissue (MALT) lymphoma is rare. This retrospective study was performed to assess the clinical profile, treatment outcome, and prognostic factors of MALT lymphoma of the salivary glands.Methods and Materials: Thirteen member centers of the Rare Cancer Network from 10 countries participated, providing data on 63 patients. The median age was 58 years; 47 patients were female and 16 were male. The parotid glands were involved in 49 cases, submandibular in 15, and minor glands in 3. Multiple glands were involved in 9 patients. Staging was as follows: IE in 34, IIE in 12, IIIE in 2, and IV in 15 patients.Results: Surgery (S) alone was performed in 9, radiotherapy (RI) alone in 8, and chemotherapy (CT) alone in 4 patients. Forty-one patients received combined modality treatment (S + RT in 23, S + CT in 8, RT + CT in 4, and all three modalities in 6 patients). No active treatment was given in one case. After initial treatment there was no tumor in 57 patients and residual tumor in 5. Tumor progression was observed in 23 (36.5%) (local in 1, other salivary glands in 10, lymph nodes in 11, and elsewhere in 6). Five patients died of disease progression and the other 5 of other causes. The 5-year disease-free survival, disease-specific survival, and overall survival were 54.4%, 93.2%, and 81.7%, respectively. Factors influencing disease-free survival were use of RI, stage, and residual tumor (p < 0.01). Factors influencing disease-specific survival were stage, recurrence, and residual tumor (p < 0.01).Conclusions: To our knowledge, this report represents the largest series of MALT lymphomas of the salivary glands published to date. This disease may involve all salivary glands either initially or subsequently in 30% of patients. Recurrences may occur in up to 35% of patients at 5 years; however, survival is not affected. Radiotherapy is the only treatment modality that improves disease-free survival. (C) 2012 Elsevier Inc.