Excretory Ducts (excretory + duct)

Distribution by Scientific Domains

Kinds of Excretory Ducts

  • main excretory duct


  • Selected Abstracts


    Recovery of rat submandibular salivary gland function following removal of obstruction: a sialometrical and sialochemical study

    INTERNATIONAL JOURNAL OF EXPERIMENTAL PATHOLOGY, Issue 6 2006
    Samira M. Osailan
    Summary Functional recovery of the rat submandibular gland following ligation of the main excretory duct was examined. Rat submandibular glands were ligated for 1, 4 and 8 weeks using a micro-clip with a plastic tube. Micro-clips were removed and glands were allowed to recover for periods of 8, 16 and 24 weeks. Submandibular glands were stimulated with autonomimetic drugs (methacholine and isoprenaline) and salivas were collected from atrophic or de-ligated and contralateral control glands. Glands recovered almost full size (92% of control gland) following 24 weeks of de-ligation. Saliva volume secreted by ligated/de-ligated (RSM) and control (LSM) glands were similar with different doses of agonists. Protein output expressed per gram of tissue wet weight was similar from both ligated/de-ligated and control glands with all doses of agonist. Sodium and chloride levels were higher from de-ligated glands than contralateral control glands. Protein electrophoresis showed similar profiles of salivary proteins in all samples with some minor differences. Acinar cells in de-ligated glands showed a normal morphology, as indicated by light microscopy, whilst granular ductal cells were fewer and contained fewer secretory granules. Sodium potassium ATPase staining of striated ducts in de-ligated glands was similar to that of control glands. It can be concluded that rat submandibular glands can regenerate following severe atrophy and secrete normal amounts of saliva containing broadly a full profile of secretory proteins. In contrast to acinar cells, ductal cells appear not to recover full function. [source]


    Salivary simulation with ascorbic acid enhances sonographic diagnosis of obstructive sialadenitis

    JOURNAL OF CLINICAL ULTRASOUND, Issue 6 2009
    Alessandro Bozzato MD
    Abstract Purpose. High-frequency ultrasound (US) is routinely used to evaluate various diseases of the salivary glands. Normally, the duct network of the submandibular and parotid glands is not visible during US assessment. In obstructive sialadenitis of the parotid and submandibular glands, localization of the obstacle is often difficult. Methods. In a case-control study, the sonographic visibility of the duct before and after stimulation with oral ascorbic acid (vitamin C) was compared with sialendoscopy as the gold standard. Twenty male and 23 female patients suffering from salivary gland diseases were included in this study and compared with 25 healthy volunteers. US examination of the parotid and submandibular glands was performed before and after oral ascorbic acid stimulation. Changes in visibility of the main excretory duct were recorded and US diagnoses were compared with results of sialendoscopy. Results. In 7 of 25 controls, the main duct became partially visible after stimulation. In the group of 43 patients, the main duct was depicted before stimulation in 27 patients (63%). After ascorbic acid stimulation, the main duct became visible in 41 patients (95%). Grading the stimulated duct dilation by measuring diameters at different points revealed no correlation with the underlying type of pathology. Conclusions. Application of ascorbic acid prior to diagnostic US examination facilitates the sonographic evaluation of obstructive salivary gland diseases. © 2009 Wiley Periodicals, Inc. J Clin Ultrasound 2009 [source]


    2331: Are the Meibomian glands "hair follicles without a hair shaft" ?

    ACTA OPHTHALMOLOGICA, Issue 2010
    E KNOP
    Purpose The Meibomian glands (MG) are atypically large sebaceous glands in the eyelids with numerous generations of secretory acini along an extensive central duct. They share similarities with the ciliary hairs in development, and hyper-keratinisation leading to obstructive MG dysfunction (MGD) represents the typical pathology. It was hence investigated which structural similarities they share with cilia. Methods Conjunctival whole-mounts including the lid margin from ten normal human body donors were embedded in paraffin. Serial sections were stained by H&E, Masson-Goldners stain and by immunohistochemistry (IHC) against cytokeratins and associated proteins. Results The terminal part (excretory duct) of the MG central duct is an ingrowth of epidermis similar to the hair follicles of the cilia. Characterization of individual cytokeratinis by IHC showed that CK14, a marker for undifferentiated cells, was expressed in the basal cell layer of the skin, MG ducts and the secretory acini. The excretory duct epithelium expressed the skin keratin CK10 and the keratinisation marker involucrin but in proximal direction along the central duct full cornification as well as both markers were gradually lost. Filaggrin, however, a marker for incipient stages of keratinisation located in keratohyalin granules continued in the superficial epithelial layer all along the MG ductal system. Conclusion All parts of the normal human MG ductal system have signs of incipient keratinisation and preserve a commitment to full cornification. This supports the assumption that the MG are basically "hair follicles without a hair shaft" in which the progression to full epithelial cornification is apparently blocked during embryological development but may reoccur under pathological influences. Support DFG KN317/11 [source]


    Immunoexpression of extracellular matrix proteins in human salivary gland development

    EUROPEAN JOURNAL OF ORAL SCIENCES, Issue 6 2004
    Cristiane Furuse
    Immunoexpression of the extracellular matrix (ECM) proteins laminin, fibronectin, tenascin and types I, III and IV collagen was analyzed in the major and minor salivary glands of seven human fetuses at different gestational ages. The results showed the presence and localization of laminin, collagen IV and fibronectin around glandular structures at all stages of development. Tenascin was only detectable around excretory ducts. In the earliest stages of development, type I and type III collagen were presented as fine fibers delineating the glandular structures and delimiting the extension of the future lobule. As glandular development proceeded, the lobule was gradually filled with collagens and glandular tissue. [source]


    Utilizing endocrine secretory pathways in salivary glands for systemic gene therapeutics,

    JOURNAL OF CELLULAR PHYSIOLOGY, Issue 1 2004
    Antonis Voutetakis
    Mammalian salivary glands are commonly used models of exocrine secretion. However, there is substantial experimental evidence showing the physiological existence of endocrine secretory pathways in these tissues. The use of gene transfer technology in vivo has allowed the unambiguous demonstration of these endocrine pathways. We and others have exploited such findings and evaluated salivary glands as possible target tissues for systemic applications of gene therapeutics. Salivary glands present numerous advantages for this purpose, including being well encapsulated, which limits extra-glandular vector dissemination, and having the luminal membranes of almost all parenchymal cells accessible via intraoral delivery of vectors through the main excretory ducts. Existing studies suggest that clinical benefits will result from salivary gland targeted systemic gene therapeutics. J. Cell. Physiol. 199: 1,7, 2004. Published 2003 Wiley-Liss, Inc. [source]


    Cystadenoma of the palate: Immunohistochemistry of mucins

    PATHOLOGY INTERNATIONAL, Issue 8 2008
    Kimihide Kusafuka
    Cystadenoma is a relatively rare benign epithelial tumor of the salivary glands, and described herein is an additional case. A 51-year-old Japanese man had noticed a mass of the left hard palate 25 years previously. Macroscopically, the resected specimen was a multicystic lesion. Histologically, the tumor was composed of bilayered columnar epithelium with cystic change and partial solid growth of glandular structures with clear cells. The tumor cells had mild cellular atypia, but the tumor lacked papillary growth and a fibrous capsule. Immunohistochemistry was positive for cytokeratins, epithelial membrane antigen, MUC1, MUC4 and MUC6, but negative for myoepithelial markers, MUC2, MUC5AC and MUC5B. Such MUC expression patterns suggested that cystadenoma occurs from excretory ducts. [source]


    Structure of the Oesophagus and Morphometric, Histochemical,Immunohistochemical Profiles of the Oesophageal Gland During the Post-hatching Period of Japanese Quails (Coturnix coturnix japonica)

    ANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 5 2009
    H. Sa
    Summary In the oesophagus, mucins, which originate from oesophageal submucosal glands, play an important role in the mucosal protection as a pre-epithelial barrier. In this study, the structure of cervical and thoracic parts of oesophagus of Japanese quail during the post-hatching period was compared, and the contents of carbohydrate and gastric mucin MUC5AC of the oesophageal glands in these parts were analysed at the light microscope levels by applying conventional histochemical and immunohistochemical methods. The oesophageal glands were present at hatching, located in the laminae propria. The numbers of glands were different in the cervical and thoracic parts, but the differences were found to be insignificant. The thoracic part has the oesophageal tonsils which are associated with the glands. Oesophageal tonsil was formed from day 5 after hatching. In quail of all ages, the secretory epithelium of glands contained neutral sialomucins and weakly sulphomucins. The cells in the neck region of secretory units contained sialomucins, while the cells of excretory ducts had strongly sulphomucins. Sialomucin containing cells in the secretory units increased with the advance of age and glandular development. But, in the secretory units, the sulphomucin content of glands was more in the thoracic part. The secretory epithelium of tonsil-associated glands contained mostly sulphomucins and a little sialomucin. From the hatching, MUC5AC mucin was detected in the cells of excretory ducts. Although the lymphoepithelium of the tonsil units exhibited negative reactions to all histochemical methods, it showed positive reaction to MUC5AC mucin antibody. In conclusion, the cervical and thoracic parts may be functionally different and the thoracic part of oesophagus was transformed into an immunological organ following day 5 after hatching. [source]


    Female mice are more susceptible to developing inflammatory disorders due to impaired transforming growth factor , signaling in salivary glands

    ARTHRITIS & RHEUMATISM, Issue 6 2007
    Seshagiri R. Nandula
    Objective Transforming growth factor , (TGF,) plays a key role in the onset and resolution of autoimmune diseases and chronic inflammation. The aim of this study was to delineate the precise function of TGF, signaling in salivary gland inflammation. Methods We impaired TGF, signaling in mouse salivary glands by conditionally inactivating expression of TGF, receptor type I (TGF,RI), either by using mouse mammary tumor virus,Cre mice or by delivering adenoviral vector containing Cre to mouse salivary glands via retrograde infusion of the cannulated main excretory ducts of submandibular glands. Results TGF,RI,conditional knockout (TGF,RI-coko) mice were born normal; however, female TGF,RI-coko mice developed severe multifocal inflammation in salivary and mammary glands and in the heart. The inflammatory disorder affected normal growth and resulted in the death of the mice at ages 4,5 weeks. Interestingly, male TGF,RI-coko mice did not exhibit any signs of inflammation. The female TGF,RI-coko mice also showed an increase in Th1 proinflammatory cytokines in salivary glands and exhibited an up-regulation of peripheral T cells. In addition, these mice showed an atypical distribution of aquaporin 5 in their salivary glands, suggesting likely secretory impairment. Administration of an adenoviral vector encoding Cre recombinase into the salivary glands resulted in inflammatory foci only in the glands of female TGF,RI,loxP-flanked (floxed) mice (TGF,RI-f/f mice), but not in those of male and female wild-type mice or male TGF,RI-f/f mice. Conclusion These results suggest that female mice are uniquely more susceptible to developing inflammatory disorders due to impaired TGF, signaling in their salivary glands. [source]


    Occurrence of lacrimal gland tissue outside the lacrimal fossa: comparison of clinical and histopathological findings

    ACTA OPHTHALMOLOGICA, Issue 1 2005
    Ghassan Ayish Alyahya
    Abstract. Purpose:,To analyse clinical referral diagnoses and the location of lesions with histologically verified lacrimal gland tissue occurring outside the fossa of the lacrimal gland. Methods:,Sections of lesions excised from areas outside the fossa of the lacrimal gland containing lacrimal gland tissue on histological examination were collected from the files of the Eye Pathology Institute, Copenhagen, Denmark. Specimens spanned a period of 50 years. Sections were re-examined and referral data on location and clinical diagnosis were compared with histological findings. Results:,A total of 120 lesions were collected. Of these, 59 (49%) consisted of prolapsed lacrimal gland. The remaining 61 (51%) lesions contained ectopic lacrimal gland tissue, either as part of a complex choristoma in 38 (32%) cases, or as solitary ectopic lacrimal gland tissue in 23 (19%) cases. The majority (97; 81%) of lesions had been located at the temporal epibulbar conjunctiva and included mainly prolapsed lacrimal gland and complex choristoma. The clinical referral diagnoses covered a wide spectrum of lesions. The most frequent clinical diagnoses were non-specific tumour (35%), non-specific cyst (18%) and dermoid (11%). Of the 61 lesions containing ectopic lacrimal gland tissue, only two had been preoperatively diagnosed as such and only two of the 59 lesions with prolapsed lacrimal gland had been correctly diagnosed. Conclusions:,Prolapsed palpebral lobe of the lacrimal gland was the most common lesion and, as expected, the prime location was the temporal conjunctiva. Despite this location, the referring clinical diagnosis was often wrong or non-specific. Surgeons seem to have been unaware of the various clinical manifestations of extrafossal glandular tissue, particularly when excising lesions in the upper temporal region of the conjunctiva. Surgical intervention in this location may jeopardize the excretory ducts of the lacrimal gland and may consequently lead to dry eye and thus should be avoided when the typical clinical appearance of prolapsed lacrimal gland is encountered. [source]