Oral Cavity and Salivary Glands Anatomy.

Knowledge of anatomy is essential to the understanding of disease and conditions of the oral cavity and salivary glands. This article is intended to serve as an overview of the oral cavity, its subsites, and that of the neighboring salivary glands. The authors cover the anatomy of the lips, tongue, floor of mouth, hard palate, teeth, various mucosal areas, and salivary ducts. When appropriate, radiological imaging along with figures serves as a companion to highlight the clinical relevance and practical applications of specific anatomic locations.

Revisión anatómica de la cavidad oral, glándulas salivares y esófago de dos ejemplares de pudú (Pudu puda) / Anatomical review of the oral cavity, salivary glands and esophagus of two specimens of pudú (Pudu puda)

RESUMEN: El pudú (Pudu puda), pertenece al orden Artiodactyla y a la familia Cervidae, corresponde al segundo cérvido más pequeño del mundo y es endémico de Chile y Argentina. Son herbívoros que se alimentan de hojas jóvenes y brotes de algunos árboles, arbustos, hierbas, frutos y flores. Esta especie está catalogada en estado Vulnerable, por lo que se prohíbe su caza y captura, esto debido a que su población ha disminuido sustancialmente a causa de la pérdida y fragmentación de la vegetación nativa, los incendios forestales, ataques de perros asilvestrados y caza furtiva. Existe escasa información científica anatómica de esta especie, y más aún referente a su morfología digestiva, por lo que se requieren estudios que aporten información específica de este cérvido. Se utilizaron dos cadáveres de pudú hembras adultas, los cuales fueron donados por el Servicio Agrícola y Ganadero (SAG) de Talca, Región del Maule, Chile. Dentro de los resultados, podemos indicar que la cavidad oral, glándulas salivares y esófago se asemejan a otros rumiantes domésticos, como también existen semejanzas con el venado de campo, sin embargo, existen diferencias como la forma y desarrollo de la glándula parótida; el conducto parotídeo pasa ventral al músculo masetero y se abre en una papila a nivel del tercer premolar superior; la glándula mandibular se divide en tres lobos; la glándula sublingual solo posee porción polistomática, las glándulas bucales dorsales poseen un menor tamaño que las bucales ventrales, la glándula bucal ventral es alargada y de forma compacta y se observa la presencia de una redondeada glándula bucal intermedia, poseen 11 crestas palatinas por lado en el paladar duro y además la papila incisiva se encuentra rodeando al pulvino dental. Esta información es relevante y corresponde a un aporte al conocimiento específico de esta especie, la cual es endémica, vulnerable y protegida.

SUMMARY: The pudu (Pudu puda), belongs to the Artiodactyla order and the Cervidae family, corresponding to the second smallest deer in the world and is endemic to Chile and Argentina. They are herbivores that feed on young leaves and shoots of certain trees, shrubs, herbs, fruits, and flowers. The status of is species is classified as Vulnerable; therefore, its hunting and capture is prohibited, this because its population has decreased substantially due to the loss and fragmentation of native vegetation, forest fires, attacks by feral dogs and poaching. There is little scientific anatomical information available on this species, and even more so regarding its digestive morphology, which is why studies are required to provide specific information on this deer. Two adult female pudu specimens were used, which were donated by the Agricultural and Livestock Service (SAG) of Talca, Maule Region, Chile. Among the results, we can indicate that the oral cavity, salivary glands and esophagus resemble other domestic ruminants; there are also similarities with the field deer, however, there are differences such as the shape and development of the parotid gland; the parotid duct passes ventral to the masseter muscle and opens into a papilla at the level of the upper third premolar; the mandibular gland is divided into three wolves; the sublingual gland only has a polystomatic portion, the dorsal buccal glands are smaller than the ventral buccal glands, the ventral buccal gland is elongated and compact and the presence of a rounded intermediate buccal gland is observed, it has 11 palatal ridges per side in the hard palate and also the incisive papilla is found surrounding the dental pulvino. This information is relevant and corresponds to a report on the specific knowledge of this species, which is endemic, vulnerable, and protected.

Labial and buccal minor salivary glands of the dog - location, three-dimensional arrangement and histology.

OBJECTIVE: Transplantation of minor salivary glands (MSGs) to the conjunctiva is a treatment option for patients suffering from dry eye disease. As there is not enough information about labial and buccal MSGs in dogs, the aim of this study was to provide evidence of the presence of these glands and to investigate their spatial arrangement and excretory ducts. METHODS: The oral mucosa of the lower lip of 4 dogs and the whole lower jaw of 1 dog were used for histological and microCT analysis. Presence, number, volumes and the tissue depth of MSGs were assessed. RESULTS: Histological analysis showed that compact tubulo-acinar glands were located in the submucosal connective tissue. MicroCT images revealed that 9 to 21 MSGs were arranged in a single row at the level of the dental alveolae. The volume of the MSGs increased from rostral to caudal and the total volume of glandular tissue per animal ranged from 35.01 mm3 to 549.43 mm3 . The mean tissue depth of MSGs ranged from 0.57 mm to 1.37 mm (upper surface of glands) and between 1.43 mm and 3.09 mm (lower surface of the glands). Excretory ducts left the dorsal part of the glands and ran in dorso-rostral direction. CONCLUSIONS: The location, number and volume of the labial and buccal MSGs in the dog could be detected and described using microCT scans and histology. The present results can provide valuable information for future transplantation of labial MSGs as therapeutic measure against keratoconjunctivitis sicca.

Discovery of new salivary gland - A substantial histological analysis.

Regardless of the COVID-19 pandemic in 2020, discovering a new salivary gland turned into all the rage among the medical fraternity. The significance of the disclosure has been correlated with its clinical relevance in radiotherapy of oropharyngeal carcinoma. However, there are views against this new revelation, owing to the lack of substantial evidence. We have endeavoured to illuminate Tubarial glands with potential shreds of evidence.

Salivary glands in workers of Ruptitermes spp. (Blattaria, Isoptera, Termitidae, Apicotermitinae): a morphological and preoteomic approach.

Salivary glands are omnipresent in termites and occur in all developmental stages and castes. They function to produce, store, and secrete compounds, ranging from a feeding function to defensive mechanisms. Here, we provide a complete morphological overview of the salivary glands in the soldierless species Ruptitermes reconditus and R. xanthochiton, and the first proteomic profile of the salivary glands in a Neotropical Apicotermitinae representative, R. reconditus. Salivary glands from both species were composed of several acini, roughly spherical structures composed of two types of central cells (type I and II) and peripheral parietal cells, as well as transporting ducts and two salivary reservoirs. Central cells were richly supplied with electron-lucent secretory vesicles and rough endoplasmic reticulum, a feature of protein-secreting cells. Parietal cells of Ruptitermes spp. had conspicuous characteristics such as electron-lucent secretory vesicles surrounded by mitochondria and well-developed microvilli. Moreover, different individuals showed variation in the secretory cycle of salivary acini, which may be related to polyethism. Ultrastructural analysis evidenced a high synthesis of secretion and also the occurrence of lysosomes and autophagic structures in central cells. Proteomic analysis of the salivary glands revealed 483 proteins divided into functional groups, highlighting toxins/defensins and compounds related to alarm communication and colony asepsis. Soldierless termites are quite successful, especially due to morphological adaptations of the workers, including unknown modifications of exocrine glands. Thus, according to our morphological and proteomic findings, we discuss the potential roles of the salivary gland secretion in different social aspects of the sampled species.

Further Research Needed to Understand Relationship Between Tubarial Glands and Eustachian Tube Dysfunction.

The pathophysiology of eustachian tube dysfunction (ETD) remains poorly characterized, and it may result in significant patient morbidity. A recent study has identified a collection of previously unidentified salivary glands in the nasopharynx that overlay the torus tubarius. While salivary gland tissue has been described in the nasopharynx, the newly discovered salivary gland tissue has been denoted tubarial glands (TGs) and theorized to be a distinct organ. The TGs have been suggested to aid in lubrication of the oropharynx and nasopharynx. However, the exact clinical significance of TGs is unknown. Given the proximity of the TG to the eustachian tube, it is possible that the TGs may be related to the development of ETD. Future studies of the TGs and related pathophysiology may improve approaches to developing future ETD treatments.

Reactivity of human labial glands in response to cevimeline treatment.

Among the pathologies affecting the salivary glands, the Sjögren's syndrome (SS), an autoimmune disease, causes progressive destruction of the glandular tissue. The effect of SS is particularly evident on the labial glands and the morphological analysis of these minor glands is considered useful for diagnosis. Cevimeline hydrochloride (SNI), a selective muscarinic agonist drug, is one of the elective treatments for the hyposalivation due to SS, acting not only on major salivary glands, but also on labial glands since their secretion is primarily under parasympathetic control. Aim of this study is to describe the morphology of human labial glands treated with SNI by light, transmission, and high-resolution scanning electron microscopy. Moreover, a morphometric analysis was applied to the light and transmission electron microscopy micrographs to obtain data that were then compared with analogous data collected on control and carbachol-treated labial glands. Following SNI administration, the mucous tubules exhibited enlarged lumina, which were filled with a dense mucous secretion. Occasionally, small broken debris of the cells were retrieved into the lumen. In the mucous secretory cells, some mucous droplets fused to form a large vacuole-like structure. Similarly, the seromucous acini showed both dilated lumina and canaliculi. These above reported signs of secretion were confirmed through morphometric analysis and a milder action of SNI than carbachol on labial parenchyma was observed. This study confirmed that SNI also evoked secretion on labial glands and that its effect is more physiologic than that of the pan-muscarinic agonists.

Detailed gross anatomic and sialographic characteristics of major salivary glands in water buffaloes (Bubalus bubalis).

To clarify the detailed general architecture and topography of major salivary glands and demonstrate a fine anatomy of the ductal system of the glands in water buffaloes, we conducted gross anatomic and sialographic investigations of glands in 14 half heads from seven water buffaloes. The position of the mandibular gland, course of mandibular duct relative to monostomatic gland, a rostral extension of polystomatic gland, and site of origin of monostomatic duct in buffaloes essentially differed from those of various ruminants. The shape of the parotid and mandibular glands, and origin of their ducts, lacking filling of retromandibular fossa by parotid gland, the topography of mandibular gland relative to the parotid gland and mandibular lymph node, caudal extension of polystomatic gland, rostral extension of monostomatic gland, and location of polystomatic gland relative to monostomatic gland in buffaloes were very similar to those in ox. However, several considerable differences in morphology of glands in buffaloes and ox were recognized. Major salivary glands in buffaloes almost show 'grazing ruminants' morphological and morphometrical characteristics. Within parotid, mandibular, and monostomatic glands in buffaloes, there was a ductal arborization pattern in lateral sialograms. Whereas the main parotid duct was formed by a union of two central branches of the intraglandular duct, main mandibular, and monostomatic ducts were consisted of one central branch. The pattern of peripheral branches from the central branch of intraglandular duct in buffaloes was significantly different among the glands. Our detailed sialography of ductal morphology and morphometry can be helpful in accurate diagnosis of gland diseases in live water buffaloes.

Simplified and rapid staining of leafhopper salivary sheaths in plant tissues for electrical penetration graph waveform correlations.

Herbivorous insects in the order Hemiptera use piercing-sucking mouthparts to utilize plant sap. Among them salivary sheath feeders penetrate into the plant by their flexible stylets to reach vascular elements. Manoeuvering stylets in plant tissues is aided by the creation of salivary sheaths, which solidify from proteinous gelling saliva and remain as lasting artefacts in the plant tissues. Studying their structure reveals hidden details of the feeding behaviour and the transmission of pathogens in case of vector insects. One important aspect of studying salivary sheaths is that it can be used to confirm the biological function of electropenetrography (EPG) waveform patterns. Previously, complex and vaguely documented histological methods have been used to observe salivary sheath structure. Building on existing methodologies, we report a simplified histological procedure where each step was optimized to offer a rapid process that does not require special equipment, can be applied to many samples, has good success rate and a low cost of errors in terms of time and materials. We describe the procedure, using a Psammotettix alienus - barley model system, in three steps. (i) Clarification of entire plant parts and pre-staining salivary sheaths with aqueous fuchsin. This step allows to identify salivary sheath starting points on the surface. (ii) Knowing salivary sheath location, using hand sectioning, produce a single c. 60 µm section that contains the entire salivary sheath. (iii) Counterstain the section with methylene green and, after further clarification, study under light microscope in a glycerol - ethanol embedding solution, without fixed mounting.

Gross morphology and ultrastructure of the salivary glands of the stink bug predator Eocanthecona furcellata (Wolff).

Eocanthecona furcellata Wolff (Hemiptera: Pentatomidae) is a native generalist predator which attacks and kills its prey by first inserting its stylet into the prey's body and then injecting saliva into it. Here, we describe the histology and ultrastructure of its salivary glands. The study showed that the salivary glands were made up of pairs of principal and tubular accessory salivary glands. The principal salivary glands were bilobed and consisted of a smaller anterior lobe and a larger elongated posterior lobe. The ducts of the principal and accessory salivary glands were located in a narrow region between the anterior and posterior lobe known as the hilum. The principal salivary gland was lined with a single-layered epithelium. The cells cytoplasm was enriched with rough endoplasmic reticulum and secretory, and the nucleus showed a higher level of uncondensed chromatin. The basal region of the cell had plasma membrane infoldings. The cytoplasm of the accessory gland was rich in rough endoplasmic reticulum and many large cavities. The ducts of the principal salivary gland were made up of a single layer of flattened cells which had a thin cuticle lining the apical portion. Variation in the lumen content of the different lobes, which made up the principal gland suggested that their chemical products also varied. These results indicate that these two salivary glands produce the proteins found in the saliva.

Salivary gland ultrasound training: Improving anatomic identification in residents.

OBJECTIVES/HYPOTHESIS: The aim of the study was to introduce and study the role of standardized views for ultrasound of the major salivary glands in resident learning and retention. STUDY DESIGN: Methods description and prospective case series. METHODS: Five otolaryngology residents and two patient models were recruited for this study. The participants were timed on their identification of the submandibular gland, sublingual gland, and parotid gland and associated key anatomic structures. Participants were then timed again immediately after being presented a standardized view for each salivary gland: the longitudinal submandibular gland, transverse parotid gland, and submental transverse views. The same participants were then timed one month later to determine retention. A Wilcoxon signed-rank test was used to evaluate whether time to identification was equal pre- and post-standardized view instruction. RESULTS: There was a significant improvement from pre- to post-standardized view instruction in all glands, which was sustained one month later. Practically speaking, assessment times for all participants at the one-month measurement were reasonable, with averages of 71, 42, and 114 s for the submandibular gland, sublingual gland, and parotid gland respectively. CONCLUSIONS: Standardized views provided otolaryngology ultrasonography learners with a reliable, fast, and memorable way to assess the salivary glands and their related structures. LEVEL OF EVIDENCE: 4.

Características morfocuantitativas de la glándula submandibular de ratón (Mus musculus) / Morphocuantitative characteristics of the mouse (Mus musculus) submandibular gland

El ratón (Mus musculus) es un buen modelo animal de experimentación, donde sus glándulas salivales han sido utilizadas en estudios, especialmente de tipo preclínico. Sin embargo, las diferencias en la morfología de estas glándulas y, en particular de las submandibulares, entre humanos y roedores no son de conocimiento común. Por lo anterior, el objetivo de este estudio fue conocer las características morfocuantitativos de la glándula submandibular del ratón macho C57BL/6. Se utilizaron cinco ratones macho, cepa C57BL/ 6, de 11 a 13 semanas de nacidos, con un peso promedio de 30 g. Luego de su ambientación, los ratones fueron eutanasiados. Para el análisis histológico, las glándulas fueron extraídas y fijadas en formalina tamponada por 48 horas, procesada para su inclusión en paraplast y teñidas con hematoxilina y eosina, azul alcián pH 2,5, ácido peryódico de Schiff y Picrosirius Red. Se determinaron las características estereológicas de densidad de longitud (LVcond), de volumen (VVcond) y de superficie (SVcond) de los conductos. En las células acinares se evaluó la densidad de número (NVcel) y la densidad de volumen (VVcel). Para cada variable se obtuvo la media ± desviación estándar. La glándula submandibular se encontraba organizada de manera lobulada, cuyo parénquima era de tipo túbuloacinar mixto con predominio seroso, que se conectaba a través de conductos. Las células acinares presentaban reacción positiva para azul alcián y ácido peryódico de Schiff. El estroma de la glándula contenía principalmente colágeno tipo 1. Los resultados de las mediciones estereológicas fueron: LVcond = 220,02 ± 50,51 mm/mm3; VVcond = 50,48 ± 9,55 %; SVcond = 26,39 ± 5,45 mm2/mm3; NVcel = 16,85 x 104 ± 9,13 × 104/mm3; VVcel = 24,98 ± 6,22 %. Con los análisis presentados es posible realizar investigaciones experimentales, considerando las similitudes y diferencias morfocuantitativas que presenta la glándula submandibular de ratón macho, cepa C57BL/6 con la del humano.

The mouse (Mus musculus) is a good experimental animal model, where murine salivary glands have been widely used in research by their similarities with human glands. Stereology is a tool that has to demonstrated to be valuable in biomedical researc h. Therefore, the objective was to realize an analogy between morphology, function and morpho-quantitative characteristics of the C57BL/6 mouse submandibular gland. Five male mice, C57BL/6, from 11 to 13 weeks old were used, with an average weight of 30 g. After seven days, the mice were euthanized and the samples were extracted. Then, these were processed following the conventional histological processing protocol and stained with H&E, Picrosirius Red, AA and PAS. Finally, the histological and stereological analysis of the samples was performed. In the glandular ducts the length density (LVcond), volume density (VVcond) and surface density (SVcond) were determined; whereas, in the acinar cells the density of number (NVcel) and the density of volume (VVcel) were evaluated. For each stereological variable the mean ± standard deviation was obtained. The histological study revealed no discrepancies as previously described. Descriptive statistical analysis revealed the following: LVcond = 220.02 ± 50.51 mm/mm3; VVcond = 50.48 ± 9.55 %; SVcond = 26.39 ± 5.45 mm2/mm3; NVcel = 168467.38 ± 91288.67 /mm3 and VVcel = 24.98 ± 6.22 %. From this study, it will be possible to conduct comparative experimental research analyzing quantitative results from those presented in this research. From this study, it will be possible to carry out comparative experimental research, analyzing quantitative results from those presented in this investigation.

Caso clínico. Diagnóstico precoz del carcinoma mucoepidermoide. A propósito de un caso clínico / Early diagnosis of mucoepidermoid carcinoma. Case report

El carcinoma mucoepidermoide (CME) se define como una neoplasia maligna epitelial de glándulas salivales, caracterizada histopatológicamente por la proliferación de células mucosecretoras, intermedias y epidermoides. Se presenta en glándulas salivales mayores como la parótida y cuando afecta a las glándulas salivales menores, el paladar es el sitio más comúnmente afectado, aunque también puede encontrarse a nivel del labio inferior, suelo de boca y trígono retromolar. El objetivo de este trabajo es describir el caso de un paciente varón de 67 años que acudió al Servicio de Cirugía del Hospital Virgen de la Paloma, presentando una lesión localizada en el trígono retromolar derecho de aproximadamente 7 meses de evolución. Su historial médico no refiere ningún antecedente personal ni familiar de especial importancia. En el examen clínico extraoral no se encontró ningún hallazgo patológico de interés, e intraoralmente presentaba una lesión tumoral con forma irregular y superficie lisa, localizada en el trígono retromolar derecho, de color rojo parduzco, de consistencia blanda y dolorosa a la palpación. Se solicitó radiografía panorámica en la cual no se observó ningún hallazgo patológico, por lo que se procedió a realizar una biopsia incisional para su estudio histopatológico. La histopatología reveló la presencia de fragmentos con una proliferación neoplásica maligna en la que se reconocen células claras de aspecto mucoso, estructuras glandulares y otras con cierta disposición quística, al igual que la presencia de placas epiteliales de aspectos epidermoides, con células intermedias y un epitelio mucoso superficial con paraqueratosis, obteniéndose finalmente un diagnóstico definitivo de CME. El CME se considera una neoplasia maligna agresiva, que obliga a dar seguimiento a cualquier lesión sospechosa para poder descartar o corroborar esta entidad

Mucoepidermoid carcinoma (MEC) is defined as a epithelial malignant neoplasm of the salivary glands, characterised histopathologically by the proliferation of mucus-secreting, intermediate and epidermoid cells.It appears in major salivary glandes such as the parotid gland and when it affects the minor salivary glands, the palate is the most commonly affected site, although it can also be found at the level of the lower lip, floor of the mouth and retromolar trigone. The objective of this paper is to describe the case of a male patient of 67 years of age who came to the surgical service, presenting a lesion located in the right retromolar trigone of approximately 7 months of evolution.His medical history does not report any personal or family background of special importance. During the extraoral clinical examination, no pathological finding of interest was found; intraorally he presented a tumoral lesion with an irregular shape and smooth surface, located in the right retromolar trigone, of a dark red colour, soft consistency and tender to touch. A panoramic x-ray was requested in which no pathological finding was observed, for which reason an incisional biopsy was performed for its histopathological study. The histology revealed the presence of fragments with a malignant neoplastic proliferation in which clear cells of a mucous appearance, glandular structures and others with a certain cystic arrangement were recognised, as well as the presence of epithelial plaques of an epidermoid appearance, with intermediate cells and superficial mucous epithelium with parakeratosis, finally obtaining a definitive diagnosis of Mucoepidermoid carcinoma MEC is considered an aggressive malignant neoplasm, which requires the monitoring of any suspicious lesion in order to be able to rule out or corroborate this entity

The anatomical basis and rational for the transoral approach during the surgical excision of the sublingual salivary gland for the management of plunging ranula.

PURPOSE: The aim of this study was to illustrate and confirm that the complete intraoral excision of the sublingual gland alone, is anatomically the most rational approach, for the management of plunging ranula. MATERIAL AND METHODS: We retrospectively reviewed clinical charts of diagnosed HIV-infected patients presenting with plunging ranula. The intraoral approach was used for the complete excision of the sublingual gland with evacuation of the pseudocystic content only. Neither extra oral approach, nor ranula dissection / drainage was performed. The surgical procedure was performed using local anesthesia. Pre- and postoperative MRI-scan investigations were recorded. Histological reports were documented to confirm the diagnosis of oral mucocele. Patients were clinically monitored. RESULTS: We identified 90 adults presenting with oral mucocele, type ranula. Seventy (77%) of them were diagnosed with HIV infection. Plunging ranula was recorded in 35 (50%) patients from the latter group. The study enrolled 11 operated patients whose files contained useable data, including an acceptable follow-up period. The postoperative follow-up period ranged from three to 15 months. The clinical and postoperative MRI-scans of operated patients demonstrated satisfactory results. There were neither postoperative complications nor recurrence of ranula reported. CONCLUSION: The location of the sublingual gland in the floor of the mouth coupled with the physio-pathogenesis of the plunging ranula, makes the transoral complete excision of the offending gland, with the intraoral evacuation of the pseudocyst, anatomically the most rational approach for plunging ranula management. There is no need for cervical approach, ranula dissection and/or postoperative placement of drainage.

Deep cervical fascia as an anatomical landmark of lingual lymph nodes: An anatomic and histologic study.

OBJECTIVES: We aimed to discuss the definition of lingual lymph nodes based on the deep cervical fascia anatomy. METHODS: A total of 11 cadavers were histopathologically evaluated. Specimens were dissected into serial stepwise cross-sections. The deep cervical fascia and lymph nodes were evaluated by staining the cross-sections with Elastica van Gieson and hematoxylin and eosin stains, respectively. The gross anatomy of the deep cervical fascia was evaluated in 1 cadaver after bilateral dissection. RESULTS: A single severely degenerated medial lingual lymph node (MLLN) was identified in the lingual septum of 1 cadaver. A single lateral lingual lymph node (LLLN) was identified in 1 cadaver, between the genioglossus and the hyoglossus. The superficial layer of deep cervical fascia (SLDF) was found to split into two layers encapsulating the submandibular gland. The deeper portion of this fascia was in close contiguity with the hyoglossus and formed the boundary between the mouth and the neck. The SLDF was found to be discontinuous with the area between the sublingual space and the submandibular gland. CONCLUSIONS: The SLDF could serve as an anatomical landmark for lingual lymph nodes, since it is considered to be the demarcating boundary during neck dissection. When lymph nodes that are located deeper than the SLDF were defined as lingual lymph nodes, 1 MLLN and 1 LLLN were identified.

Anatomy, Histology, and Ultrastructure of Salivary Glands of the Burrower Bug, Scaptocoris castanea (Hemiptera: Cydnidae).

The burrower bug Scaptocoris castanea Perty, 1830 (Hemiptera: Cydnidae) is an agricultural pest feeding on roots of several crops. The histology and ultrastructure of the salivary glands of S. castanea were described. The salivary system has a pair of principal salivary glands and a pair of accessory salivary glands. The principal salivary gland is bilobed with anterior and posterior lobes joined by a hilus where an excretory duct occurs. The accessory salivary gland is tubular with a narrow lumen that opens into the hilus near the excretory duct, suggesting that its secretion is stored in the lumen of the principal gland. The cytoplasm of the secretory cells is rich in the rough endoplasmic reticulum, secretory vesicles with different electron densities and mitochondria. At the base of the accessory gland epithelium, there were scattered cells that do not reach the gland lumen, with the cytoplasm rich in the rough endoplasmic reticulum, indicating a role in protein production. Data show that principal and accessory salivary glands of S. castanea produce proteinaceous saliva. This is the first morphological description of the S. castanea salivary system that is similar to other Hemiptera Pentatomomorpha, but with occurrence of basal cells in the accessory salivary gland.

Ultrasonographic and elastographic biometry in adult major salivary glands: a preliminary case-control report.

Specifications about the size and stiffness of healthy salivary glands with ultrasound (US) are not available for Asian people. Using a Toshiba Apolio 500 US platform, we determined the size (including anterior-posterior median length, median paramandibular depth dimension, and cranio-caudal height) and hardness of 100 healthy submandibular and parotid glands in volunteers without a history of disease affecting the salivary glands or post-radiation, and compared the dimensions to those of 36 parotid glands and 37 submandibular glands in post-irradiated patients. The dimensions of the parotid and submandibular glands were significantly correlated with body weight. However, the dimension of the parotid glands was not significantly correlated with that of patients with prior radiation; the shear wave velocity (SWV) significantly increased (1.99 m/s versus 2.43 m/s, p-value < 0.01). The dimension of the submandibular glands was significantly correlated with prior radiation, where the SWV also significantly increased (2.32 m/s versus 2.50 m/s, p-values < 0.01). We find that US is a useful tool for assessment of the reference dimensions and hardness of major salivary glands that may be altered by irradiation.

Morphology of the mandibular gland of the ant Paraponera clavata (Hymenoptera: Paraponerinae).

The ant Paraponera clavata (Fabricius, 1775) is the only extant species of Paraponerinae and is widely distributed in Brazilian forests. Aspects of its biology are documented extensively in the literature; however, knowledge of P. clavata internal morphology, specifically of exocrine glands, is restricted to the venom apparatus. The objective of this study was to describe the mandibular gland morphology of P. clavata workers. The mandibular gland is composed of a reservoir connected to a cluster of Type III secretory cells with cytoplasm rich in mitochondria and lipid droplets, similar to that of other ants. Notably, the glandular secretion is rich in protein and has a solid aspect. This is the first morphological description of the mandibular gland of P. clavata. RESEARCH HIGHLIGHTS: This study presents the morphological description of the mandibular gland of Paraponera clavata (Hymenoptera: Paraponerinae). Singular characteristics of the gland are described: the glandular secretion is rich in protein and has a solid aspect.

Histological and histochemical characterisation of glands associated with the feeding appendages of Argulus foliaceus (Linnaeus, 1758).

Argulus foliaceus (Linnaeus, 1758) is a member of the branchiuran family Argulidae, a group comprising parasitic "fish lice". A. foliaceus is distributed worldwide and causes major economic impacts for cultured freshwater fish globally. The work described in this study was undertaken with the objective of identifying, describing and characterising glands associated with feeding in A. foliaceus. From structural and ultrastructural microscopic studies of A. foliaceus, three types of gland were determined to be associated with the pre-oral spine and mouth tube and were suggested to be involved in feeding activities. Two of these glands, the labial glands and the proboscis glands, appeared to secrete their products via the mouth tube and a third, the spinal gland, was connected directly to the pre-oral spine. The current study confirmed that the pre-oral spine delivers active secretions from the spinal gland, which may aid in immunomodulation, while the tubular labial spines and proboscis glands openings within the mouth tube may serve to enhance the feeding process by delivering salivary components to aid pre-digestion and immune-modulate the host. The suggested functions are supported by histological and histochemical staining, coupled with fluorescent lectin-binding assays, which enabled characterisation of the carbohydrate moieties associated with these glandular tissues.