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F Paulsen

Publications and source records attributed to F Paulsen.

At least 37 records · Page 2Linked to original sources
PubMed2001

[The efferent lacrimal ducts of the human. Morphological and biochemical studies].

PURPOSE: Infections occur frequently in the region of the efferent tear ducts. Exact knowledge of the anatomical structure and of cellular defense mechanisms is necessary to understand the pathological processes. This study analyzed the efferent tear ducts with regard to physiological function and possible defense mechanism against infections. MATERIALS AND METHODS: We used histological, immunohistochemical and electronmicroscopic techniques to investigate the lacrimal systems from 31 body donors aged 54-88 years. RESULTS: The efferent tear ducts are lined by a double-layered epithelium resting on a broad basement membrane. These cells contain many lipid droplets and secretory vacuoles in their apical part. Inside the epithelium cells are arranged partly in cell groups forming mucous glands, which morphologically resemble goblet cells of the tarsus palpebrae. The secretory products of these cells contain various carbohydrates including sialic acid. Lymphocytes and macrophages are found in the submucosa partly penetrating the epithelium. CONCLUSIONS: Lipids and mucins of epithelial and goblet cells form a specialized protective layer on the epithelium of the tear ducts which enables easy drainage of tear fluid into the inferior meatus of the nose. Together with immunocompetent cells the protective layer prevents invasion of pathogenetic agents.

Aged↗
PubMed2001

Comparative evaluation of pulmonary lactoferrin and lysozyme immunoreactivity for the postmortem diagnosis of death due to sepsis.

To determine whether lactoferrin (LF) and lysozyme (LZ) can be used as immunohistochemical postmortem markers of sepsis, pulmonary tissue sections from autopsy cases of sepsis-related fatalities (n = 13) and control cases of non-septic fatalities (n = 14) were evaluated for differences in leucocytic immunoreactivity. LF and LZ were investigated in paraffin sections using the AEC technique. The immunohistochemical expression of both markers was scored, evaluating the quantity of immunopositive cells and the intensity of the intracellular immunoreactivity. There was a statistically significant association between an enhanced expression of LF on pulmonary leucocytes in sepsis-related fatalities in contrast to non-sepsis cases (P < 0.001), whereas no such difference could be observed for LZ immunoreactivity between the two study groups. Pneumonic tissue alterations had no significant influence on LF and LZ immunoreactivity, thus suggesting differences between the degranulation of these non-specific antibacterial agents in local and systemic inflammatory processes. While the variability of LZ immunoreactivity, possibly reflecting a non-specific release from lysosomes according to the length of the postmortem interval, limits its application to the postmortem diagnosis of sepsis, the immunohistochemical detection of an enhanced expression of LF can contribute to the postmortem discrimination between sepsis and non-septic fatalities.

Adolescent↗
PubMed2001

[Meta-analysis of the efficacy of positron emission tomography with F-18-fluorodeoxyglucose in lung tumors. Basis for discussion of the German Consensus Conference on PET in Oncology 2000].

BACKGROUND: : To analyse current literature on FDG-PET for evaluation of lung lesions, N-staging, M-staging, and recurrence of lung cancer for the third German Consensus Conference on PET in oncology. METHODS: Specialists in nuclear medicine, pneumology, radiation oncology, diagnostic radiology, and thoracic surgery reviewed the relevant literature as listed in MEDLINE from 1985 to 1999 for further analysis. Out of the published data cumulative test parameters and summary receiver operating characteristic curves (sROC curves) were computed. RESULTS: Sensitivity, specificity, and accuracy of FDG-PET are 96 %, 80 %, 91 % for evaluating lung lesions (15 studies with at least 35, in total 1144 patients). With corresponding values of 88 %, 92 %, 91 % (20 studies, 1292 patients) for N-staging FDG-PET is superior to CT with 65 %, 76 %, 73 % (19 studies, 1268 patients). With 94 %, 97 %, 96 % (4 studies, 336 patients) M-staging with FDG-PET is very accurate and changed therapeutic management in 18 % of the cases (8 studies, 695 patients), unexpected extrathoracic metastases were found in 12 % (7 studies, 581 patients). FDG-PET is the most accurate non-invasive method to evaluate suspected adrenal metastases (3 studies, 263 patients, sensitivity 96 %, specificity 99 %, accuracy 98 %). Recurrence is detected accurately (4 studies, 224 patients, sensitivity 99 %, specificity 89 %, accuracy 95 %). CONCLUSIONS: Studies with in total more than 1000 patients show the high diagnostic efficacy of FDG-PET and its superiority to conventional imaging in lung cancer. Based on this analysis the third German Consensus Conference on PET in oncology evaluated FDG-PET on lung cancer. 1a-indications are evaluation of lung nodules in patients at risk for complications during surgery, N-staging, M-staging (except brain), and detection of recurrence.

Fluorodeoxyglucose F18↗
PubMed2001

[Mechanical brush-catheter abrasion method for the isolation and culture of human umbilical vein endothelial cells. First in vitro results].

UNLABELLED: Mechanical brush-catheter abrasion method for the isolation and culture of human umbilical vein endothelial cells. First in vitro results. PURPOSE: To determine the value of a nylon brush (Cragg thrombolytic catheter system) with regard to the isolation and culture of viable human vascular umbilical vein endothelial cells (HUVEC). MATERIAL AND METHODS: Fresh human umbilical cords were collected after a maximum of 6 - 8 h post delivery. They were stored in sterile tubes till further preparation. After predilation the umbilical cord veins, a 6 French brush catheter was inserted, expanded, and removed by hand using rotating movements. The nylon brush was shaken out in cell medium containing serum proteins by a connected motor drive. After repeating these procedures, the detached endothelial cells were centrifugated and resuspended. The cell numbers were assessed and cell viability controlled. RESULTS: The endothelial cell (EC) viability depended on the umbilical cord's age and was the highest (29.8 +/- 11.4 %) within 3 h after delivery. The brush abrasion (3.32 x 10(5) +/- 52016 viable EC/10 cm vein segment) enabled us to culture these cells under different cell concentrations. They grew to confluence after 2 - 3 weeks. CONCLUSIONS: The brush-catheter abrasion is an effective method for collecting viable human endothelial cells in vitro.

Catheterization, Peripheral↗
PubMed2001

Expression of natural peptide antibiotics in human articular cartilage and synovial membrane.

In view of frequent present use of invasive procedures on limb joints, it is astonishing that articular joint inflammation is a rare event. We questioned whether antimicrobial peptides play a role in protecting human articular cartilage and synovial membrane against inflammatory agents. Our results implicate defensins in the protection of human articular joints against pathogens.

Anti-Bacterial Agents↗
PubMed2001

Dendritic cells in the mucosa of the human trachea are not regularly found in the first year of life.

BACKGROUND: Dendritic cells (DCs) in the mucosa of the respiratory tract might be involved in the early development of pulmonary allergy or tolerance. To date, little is known about when the first DCs occur in human airways. METHODS: Specimens of the distal trachea from patients who had died from sudden death in the first year of life (n=29) and in older age groups (n=59) as well as from those who had died from respiratory tract infections in the first year of life (n=8) were examined by immunohistochemistry. Transmission electron microscopy was performed in additional samples from two adults. RESULTS: In the sudden death subgroup DCs were absent in 76% of those who died in the first year of life but were present in 53 of the 59 older cases. All infants who had died of respiratory infectious diseases had DCs in the tracheal mucosa. CONCLUSIONS: Mature DCs are not constitutively present in the human tracheobronchial mucosa in the first year of life, but their occurrence seems to be triggered by infectious stimuli. These data support the hypothesis that DCs play a crucial role in immunoregulation in early childhood.

Adolescent↗
PubMed2000

What happens to tears inside the efferent lacrimal passage? An animal experimental study.

BACKGROUND: To determine whether absorption of protein components of the tear fluid occurs in normal efferent tear ducts, an animal experiment was carried out. METHODS: Iodinated albumin was dropped into eyes of female rats. After 10, 20 or 60 min the rats were killed, blood collected and the heads embedded for histological examination. Serum was obtained from the clotted blood and the radioactivity in a protein sediment and the combined supernatants counted. In a second approach, serum was fractionated by molecular mass and radioactivity in the fractions measured. Furthermore, autoradiographs of rat head sections were performed. RESULTS: Uptake of radioactivity into the serum was low, but increased with time. After 60 min maximal incorporation of the applied radioactivity into the blood was 0.13%; most (70-80%) of the incorporated radioactivity was not protein bound. Gel chromatographic separation according to molecular mass yielded fractionated peaks of radioactivity corresponding to albumin with maximal 4.8 Bq/ml serum, iodinated tyrosine (5.5 Bq/ml), and free iodine (237 Bq/ml; each after 60 min). Histologically the rat efferent lacrimal tear ducts showed a multilayered lining epithelium with integrated goblet cells in a characteristic arrangement of several cells. In autoradiographs of rat head sections no transport of radioactivity could be visualized. CONCLUSION: In rats only traces of iodinated albumin are incorporated from the efferent lacrimal tear ducts into the blood. A higher proportion of the radioactivity is taken up as the proteolytic degradation product of bovine serum albumin to free amino acids, and 96% of the radioactivity incorporated was free iodine, probably as a contaminant of the iodinated preparation.

Absorption↗
PubMed2000

Effects of ageing on the insertion zones of the human vocal fold.

The vocal ligaments insert at the anterior and posterior commissures of the larynx. These structures fulfil biomechanical functions, balancing the different elastic moduli of tendon, cartilage or bone and undergo age-related changes that may be responsible for voice changes with increasing age. The aim of this study was to analyse the insertion structures of the vocal ligaments by means of macroscopic, histological, immunohistochemical and electron-microscopic methods and to draw conclusions from age-related structural changes on a functional basis. Investigations were carried out on the larynges of 22 males and 15 females (aged 1-95 y). In adolescence, the insertion zone of the vocal ligament tendon, a dense network of connective tissue rich in sulphated glycosaminoglycans at the thyroid cartilage, is characterised by a layer between tendon and cartilage comparable to fibrocartilage. The insertion zone lacks a perichondrium. Collagen fibrils of the vocal ligament tendon penetrate directly into the thyroid cartilage. In the insertion area, the chondrocytes are surrounded by collagen fibrils, which show positive reactivity to antibodies against type I and type III collagen. Sulphated glycosaminoglycans are integrated between the collagen fibrils. In the area of the posterior glottis, elastic cartilage rests like a cap on the hyaline base of the arytenoid cartilage. There is no distinctive border between the structures. With increasing age, ossification of the laryngeal skeleton occurs, involving hyaline cartilage at the posterior glottis and hyaline and fibrocartilage at the anterior commissure. At the same time, a loss or sulphated glycosaminoglycans is observed inside the vocal ligament tendon. Advanced ossification of the laryngeal skeleton, particularly in the area of the commissures, an increasing loss of glycosaminoglycans in the vocal ligament tendon and changes in the elastic tissue reduce the elastic modulus between tendon, cartilage and bone, thus 'stiffening' the insertion zones, which could be one factor among others favouring voice changes with advancing age.

Aging↗
PubMed2000

Innervation of the cavernous body of the human efferent tear ducts and function in tear outflow mechanism.

The lacrimal sac and nasolacrimal duct are surrounded by a wide cavernous system of veins and arteries comparable to a cavernous body. The present study aimed to demonstrate the ultrastructure of the nervous tissue and the localisation of neuropeptides involved in the innervation of the cavernous body, a topic not previously investigated. Different S-100 protein antisera, neuronal markers (neuron-specific enolase, anti-200 kDa neurofilament), neuropeptides (substance P, neuropeptide Y, calcitonin gene-related peptide, vasoactive intestinal polypeptide) and the neuronal enzyme tyrosine hydroxylase were used to demonstrate the distribution pattern of the nervous tissue. The ultrastructure of the innervating nerve fibres was also examined by means of standard transmission electron microscopy. The cavernous body contained specialised arteries and veins known as barrier arteries, capacitance veins, and throttle veins. Perivascularly, the tissue was rich in myelinated and unmyelinated nerve fibres in a plexus-like network. Small seromucous glands found in the region of the fundus of the lacrimal sac were contacted by nerve fibres forming a plexus around their alveoli. Many nerve fibres were positive for S-100 protein (S 100), neuron-specific enolase (NSE), anti-200 kDa neurofilament (RT 97), calcitonin gene-related peptide (CGRP), substance P (SP), tyrosine hydroxylase (TH), and neuropeptide Y (NPY). Vasoactive intestinal polypeptide (VIP) immunoreactivity was only demonstrated adjacent to the seromucous glands. Both the density of nerve fibres as well as the presence of various neuropeptides emphasises the neural control of the cavernous body of the human efferent tear ducts. By means of this innervation, the specialised blood vessels permit regulation of blood flow by opening and closing the lumen of the lacrimal passage as effected by the engorgement and subsidence of the cavernous body, at the same time regulating tear outflow. Related functions such as a role in the occurrence of epiphora related to emotional responses are relevant. Moreover, malfunction in the innervation of the cavernous body may lead to disturbances in the tear outflow cycle, ocular congestion or total occlusion of the lacrimal passages.

Adult↗
PubMed2000

Curving and looping of the internal carotid artery in relation to the pharynx: frequency, embryology and clinical implications.

Variations of the course of the internal carotid artery in the parapharyngeal space and their frequency were studied in order to determine possible risks for acute haemorrhage during pharyngeal surgery and traumatic events, as well as their possible relevance to cerebrovascular disease. The course of the internal carotid artery showed no curvature in 191 cases, but in 74 cases it had a medial, lateral or ventrocaudal curve, and 17 preparations showed kinking (12) or coiling (5) out of a total of 265 dissected carotid sheaths and 17 corrosion vascular casts. In 6 cases of kinking and 2 of coiling, the internal carotid artery was located in direct contact with the tonsillar fossa. No significant sex differences were found. Variations of the internal carotid artery leading to direct contact with the pharyngeal wall are likely to be of great clinical relevance in view of the large number of routine procedures performed. Whereas coiling is ascribed to embryological causes, curving is related to ageing and kinking is thought to be exacerbated by arteriosclerosis or fibromuscular dysplasia with advancing age and may therefore be of significance in relation to the occurrence of cerebrovascular symptoms.

Aged↗
PubMed2000

[The joint capsule of the cricoarytenoid joint: biomechanical and clinical aspects].

BACKGROUND: Impaired movement of the cricoarytenoid joint with hoarseness and immobility of the vocal ligament may occur as a consequence of laryngeal trauma and joint disease. Little is known to date about the cricoarytenoid joint capsule and its role in joint pathology. METHODS: The present study analyses the structure of the cricoarytenoid joint capsule by means of histological, immunohistochemical, and scanning electron microscopical methods. Investigations are performed on larynges of 17 male and 16 female. RESULTS: The cricoarytenoid joint was found to be lined by a wide and lax joint capsule consisting of a fibrous and a synovial membrane. The capsule was strengthened posteriorly by the cricoarytenoid ligament. As like the fibrous membrane the cricoarytenoid ligament consisted mainly of collagen types I and III. Moreover the ligament was found to be rich in elastic fibers. Unexpected large and intensively vascularized synovial folds projected into the joint cavity. CONCLUSION: The capsule of the cricoarytenoid joint can be compared with the joint capsules of the limbs despite its structure and its involvement in joint pathology. Based on the laxity of the joint capsule it was concluded that invasive interventions at the respiratory tract with dislocation of the arytenoid cartilage can lead to incarceration of the synovial folds. After a trauma aero-synovitis or formation of hemarthrosis may occur, with subsequent fixation of the arytenoid in an abnormal position.

Adult↗
PubMed2000

Orcein-picroindigocarmine--a new multiple stain.

A new "orcein-picroindigocarmine staining", a colour combination of orcein, indigo carmine, and picric acid, was developed for histological applications. The new technique was tested on different human tissues. Colours ranging from red to brown, yellow, green and blue were observed in paraffine sections of tissues stained by this method. Nuclear structures in all tissues were stained dark brown to dark blue. Squamous epithelium was stained light brown with varying shades of blue in upper horny layers, whereas the ciliated epithelium was tinged blue grey. When connective tissue was stained, collagen fibrils appeared strongly blue next to elastic fibres, which took on a rust brown tinge; cellular components were all coloured brown. The matrix of hyaline cartilage was stained in different shades of blue, with the chondrocytes rust brown. Sections of bone components appeared dark blue to dark green. Skeletal muscle cells were coloured yellow and green with blue collagenous septa. The new staining is useful for distinguishing connective tissue components such as elastic fibres and collagen fibrils. It also demonstrates chondrocytes in favourable contrast to the cartilage matrix. The technique produces aesthetic staining colouring that could supplement histological investigations and provide an alternative to other staining materials.

Adult↗
PubMed1999

Chemotherapy in the treatment of recurrent glioblastoma multiforme: ifosfamide versus temozolomide.

PURPOSE: Despite the progress made in neurosurgery and radiotherapy, the prognosis of glioblastoma multiforme (GB) is poor, due to the lack of an effective salvage therapy. In vitro analysis revealed activity for ifosfamide and temozolomide. The usefulness of these agents in recurrent disease was investigated. METHODS: Six adult patients with recurrent GB received one to four courses of 1,500 mg/m2 ifosfamide given over 5 days intravenously. Furthermore, temozolomide (100-200 mg/m2) was given orally over 5 days to 14 patients. RESULTS: After ifosfamide treatment, one partial response and two cases of stable disease were observed. The median survival time was 24 weeks (range of 9-52 weeks). Toxicity analysis revealed one paranoid reaction, three grade III leukocytopenia, and one grade I-II nausea, anemia, and hematuria. Temozolomide therapy resulted in three partial responses and four cases of stable disease. The median survival time (Kaplan-Meier) was 21 weeks (range 4-64 weeks). The major toxicities were grade I-II nausea and hematological side effects (one case of grade IV leuko- and thrombocytopenia). CONCLUSIONS: Ifosfamide treatment might be a feasible approach, but it necessitates hospitalization. Temozolomide showed promising results. Due to its oral application, the patient's quality of life (time out of hospital) is favorable. Subgroups with improved survival were observed.

Adult↗
PubMed1999

Evaluation of predictive factors for local tumour control after electron-beam-rotation irradiation of the chest wall in locally advanced breast cancer.

BACKGROUND AND PURPOSE: Different radiotherapy techniques are being used for chest wall irradiation after mastectomy. We review our results with the electron-beam-rotation technique in a series of 130 high risk breast cancer patients. The main end point of the study was local tumour control; secondary end points were disease free survival, and overall survival, as well as acute and late side effects. MATERIAL AND METHODS: From January 1990 to June 1995, 89 patients underwent electron-beam-rotation irradiation of the chest wall after primary mastectomy and axillary lymph node dissection (group I) and 41 patients after excision of local recurrent breast cancer (group II) with 4 x 2.5 Gy/week to 50 Gy total dose (4-12 MeV electrons depending on the thickness of the chest wall). In addition, irradiation of local-regional lymph nodes and/or a local boost of 10 Gy were applied dependent on the resection and node status. RESULTS: After a median follow up of 29 months (65% stadium III/IV) the 3 year local tumour control, disease free survival, and overall survival were 73%, 47%, and 75%, respectively. Local control in group I was 78% versus 60% in group II. Significant predictors for local tumour control, disease free survival, and overall survival were resection status (R0 versus R1/2) and estrogen receptor status (positive versus negative). In group I, tumour grading (GI-IIa versus GIIb-III) and estrogen receptor status were found to be additional significant prognostic factors for complete resected tumours. Five patients developed symptomatic pneumonitis (< 4%) and one patient developed a chronic fistula at the resection. A significant correlation between the degree of acute skin reaction and persistent pigmentation was observed. CONCLUSION: In high risk breast cancer patients postoperative irradiation with the electron-beam-rotation technique of the chest wall is an effective therapy resulting in 78% local tumour control at 3 years for locally advanced breast cancer and 60% for recurrent disease. The rate of acute and late toxicity is low. The degree of acute skin reaction correlates with the degree of persistent pigmentation.

Adult↗
PubMed1999

Composition of the extracellular matrix in human cricoarytenoid joint articular cartilage.

The extracellular matrix of the human cricoarytenoid joint articular cartilage is involved in different pathological changes. Interestingly, in contrast to the limb joints, the extracellular matrix composition of the healthy cricoarytenoid joint articular cartilage has not yet been elucidated except by some light microscopical investigations. The present study investigates the extracellular matrix components of the cricoarytenoid joint articular cartilage by means of light microscopy, immunohistochemistry, transmission electron microscopy and scanning electron microscopy and compares them with the limb joints for a better understanding of their involvement in joint disease. Chondrocytes near the joint surface of the cricoid and arytenoid cartilage differ from chondrocytes of deeper cartilage layers. The extracellular matrix of the articular cartilage contains chondroitin-4-sulfate, chondroitin-6-sulfate and keratansulfate as well as collagen types II, III, VI, IX and XI. Type-III-collagen shows a special distribution throughout the joint cartilage. In deeper cartilage layers, type-III-collagen occurs only pericellularly; in higher cartilage layers type-III-collagen is also located territorially and interterritorialy in small amounts. Scanning and transmission electron microscopy have revealed the articular surface of the cricoid and arytenoid cartilage to consist of a network of irregularly organized collagen fibrils, which are lined by a layer of electron dense material. The network coats subjacent collagen bundles which descend obliquely downward and intermingle at right angles in the middle part of the articular cartilage with collagen bundles of the deeper cartilage zones. The articular cartilage surface shows structural characteristics which differ from the underlying cartilage. The superficial electron dense layer possibly plays a role in the lubrication of the articular cartilage surface. The alignment of the fibrillar structures in the articular cartilage of the cricoarytenoid joint varies from those of the limb joints based on the different strain occurring during arytenoid movement. Nevertheless, the human cricoarytenoid joint articular cartilage can be compared with the joints of the limbs despite its extracellular matrix composition and its involvement in joint pathology. Evidence of type III collagen in the outermost layer of the articular cartilage of the cricoarytenoid joint presents a peculiarity, which has yet not be demonstrated in the articular cartilage of limb joints.

Adult↗
PubMed1998

Functional anatomy of the human efferent tear ducts: a new theory of tear outflow mechanism.

BACKGROUND: The mechanism of lacrimal drainage under physiological conditions is controversial. The aim of this study was to analyze the three-dimensional architecture of human efferent tear ducts from functional and clinical points of view. A new theory of tear outflow is discussed. METHODS: Thirty-two prepared lacrimal systems of adults were examined by histological, immunohistochemical and scanning electron microscopic techniques. RESULTS: The wall of the lacrimal sac is made up of collagen bundles, elastic and reticular fibers arranged in a helical pattern. Wide luminal vascular plexus are embedded in this helical system and connected to the cavernous tissue of the inferior turbinate in the region of Hasner's valve. Immunohistochemical analysis showed evidence of type I and type III collagen as well as chondroitin 4- and 6-sulfate. CONCLUSION: With blinking, the lacrimal part of the orbicularis muscle contracts. The fornix of the sac moves in a cranial-lateral direction. Thus the lacrimal sac distends and may be "wrung out" due to its medial attachment and helically arranged fibrillar structures. The vascular plexus may play an important role in the absorption and drainage of lacrimal fluid.

Aged↗
PubMed1998

Functional anatomy of human lacrimal duct epithelium.

Resorption of tear fluid in the lacrimal ducts has hitherto been controversial; one reason for this has been insufficient knowledge of the anatomical structure and function of the lacrimal duct epithelium. The present study analyzes the structure of lacrimal duct epithelium by means of histological, histochemical, immunohistochemical and electronmicroscopical methods and draws a conclusion about its physiological function regarding its role in immunodeficiency. Investigations were performed on 31 lacrimal systems of 17 male and 14 female individuals (aged 54-88 years). Lacrimal ducts are surrounded by a wide-ranging cavernous system, which is embedded in an osseous canal between the maxilla and the lacrimal bone. The internal wall of the lacrimal canaliculi is lined by a stratified epithelium. The lacrimal sac and nasolacrimal duct contain a double-layered epithelium, which rests on a broad basement membrane. In their apical part epithelial cells contain large lipid droplets and secretory vacuoles. Epithelial cells are faced by microvilli and some tufts of kinociliae are also visible. Goblet cells are integrated in the epithelium as solitary cells or in a characteristic arrangement of several cells. The secretory product of these cells contains carbohydrates including fucose and sialic acid. Inside the surrounding cavernous system serous glands are found that open their excretory ducts into the lacrimal sac and nasolacrimal duct. Some T- and B-lymphocytes and macrophages may be demonstrated immunohistochemically in the submucosa partly penetrating the epithelium. Synthesized mucins of goblet cells form a specialized protective layer on the epithelium of the lacrimal ducts, which functionally serves for a simplified drainage of tear fluid into the inferior meatus of the nose. Together with immunocompetent cells, the protective layer plays a role in antigen defense and prevents invasion of pathogenic agents. The facing of epithelial cells by microvilli gives hints of re-absorption of lacrimal fluid inside the lacrimal ducts.

Aged↗