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PubMed2005

Claudin 7 expression and localization in the normal murine mammary gland and murine mammary tumors.

INTRODUCTION: Claudins, membrane-associated tetraspanin proteins, are normally associated with the tight junctions of epithelial cells where they confer a variety of permeability properties to the transepithelial barrier. One member of this family, claudin 7, has been shown to be expressed in the human mammary epithelium and some breast tumors. To set the stage for functional experiments on this molecule, we examined the developmental expression and localization of claudin 7 in the murine mammary epithelium and in a selection of murine mammary tumors. METHOD: We used real-time polymerase chain reaction, in situ mRNA localization, and immunohistochemistry (IHC) to examine the expression and localization of claudin 7. Frozen sections were examined by digital confocal microscopy for colocalization with the tight-junction protein ZO1. RESULTS: Claudin 7 was expressed constitutively in the mammary epithelium at all developmental stages, and the ratio of its mRNA to that of keratin 19 was nearly constant through development. By IHC, claudin 7 was located in the basolateral part of the cell where it seemed to be localized to discrete vesicles. Scant colocalization with the tight-junction scaffolding protein ZO1 was observed. Similar results were obtained from IHC of the airway epithelium and some renal tubules; however, claudin 7 did partly colocalize with ZO1 in EPH4 cells, a normal murine mammary cell line, and in the epididymis. The molecule was localized in the cytoplasm of MMTV-neu and the transplantable murine tumor cell lines TM4, TM10, and TM40A, in which its ratio to cytokeratin was higher than in the normal mammary epithelium. CONCLUSION: Claudin 7 is expressed constitutively in the mammary epithelium at approximately equal levels throughout development as well as in the murine tumors examined. Although it is capable of localizing to tight junctions, in the epithelia of mammary gland, airway, and kidney it is mostly or entirely confined to punctate cytoplasmic structures, often near the basolateral surfaces of the cells and possibly associated with basolateral membranes. These observations suggest that claudin 7 might be involved in vesicle trafficking to the basolateral membrane, possibly stabilizing cytoplasmic vesicles or participating in cell-matrix interactions.

Animals↗
PubMed1991

Plasticity of intercellular junctions of rat liver lymph capillaries in relation to functional conditions.

The junctions between endothelial cells in lymph capillaries may have different degrees of complexity and have been classified as three types: "end to end" (EE), "overlapping" (OVL), and "interdigitating" (ID). Under normal conditions, the more complex junction types (ID and OVL) are more frequent than the simple type (EE). The authors' hypothesis was that not only the folds and digitations of the endothelial profile but also the prevalence of the more complex junction types under normal conditions impart plasticity and distensibility to the endothelial wall. To verify this hypothesis they performed a transmission electron microscope study of lymph capillaries of rat liver under normal conditions and after treatment with histamine, which induces natural filling of lymph vessels. In lymph capillaries of histamine-treated animals they found a significant prevalence of the simplest (EE) junctions (50 +/- 5% versus 20 +/- 4% in controls, p less than 0.001) over the more complex OVL (28 +/- 4% versus 57 +/- 4% in controls, p less than 0.001) and ID junctions (12 +/- 3% versus 19 +/- 4% in controls, NS). The overall trend in junction types showed a highly significant shift toward the simpler types after histamine treatment (p less than .0001). There was also a significant reduction in the mean length of adjoining cell borders from 1.5 +/- 0.1 m in histamine-treated animals (p less than 0.001). These findings indicate the participation of the junctions in variations in capacity of lymph vessels in rat liver. This mobilization of cell junctions may also favor the drainage of interstitial fluids into the absorbing lymph vessels.

Animals↗
PubMedDate not supplied

[Digital orthopantomography with memory phosphorus in the study of periodontal pathology].

Digital images can improve the quality of panoramic radiography also because they can be magnified by the computer in the post-processing phase. In this study, 100 patients with periodontal disease were examined with digital panoramic radiography. The degree of alveolar bone resorption was assessed by measuring the depth of infraosseous pouches. The distance between the amelodental junction and the alveolar ridge was considered abnormal when it exceeded 1-1.5 mm. Our results confirm the high quality of digital panoramic radiographs which were always rich in details and allowed the clear depiction of the alveolar edge. The incidence and depth of infraosseous pouches are higher in older patients (mean distance between the amelodentinal junction and the alveolar ridge > 4 mm in patients over 40). The measurements made on digital panoramic radiographs and on intraoral films were compared and high agreement was observed (+/- 1 mm disagreement in 80% of measurements). In our experience, digital panoramic radiography can be considered a valuable diagnostic alternative to intraoral films to study periodontal disease and to measure bone resorption.

Adult↗
PubMed1986

Morphology and distribution of cystic cavities in the normal murine thymus.

The normal murine thymus was examined by light- and electron microscopy to determine the distribution and morphology of extracellular cystic cavities. Most cavities were confined to the cranial half of each gland, situated at the junction between cortex and medulla. They varied in size and shape, and gave rise to narrow channels that coursed to the capsular surface of the gland. Large cavities could be divided into three zones. A short cranial zone exhibited gland-like features, consisting of cells lining a clear lumen. A central zone was lined by a diverse population of cells. Some possessed secretory granules, while others exhibited an apical ciliated border. Lining cells inter-digitated with each other and were joined laterally by intercellular junctions. The lumen of the central zone contained lymphocytes and macrophages in an amorphous extracellular matrix. The caudal zone of each cavity had an attenuated and incomplete cellular lining, communicating directly with the surrounding thymic parenchyma. Thymic cavities may represent the initial part of the efferent lymphatic system of the gland, beginning in the tissue spaces at the corticomedullary junction. Selected cells could then enter and interact with the luminal contents in the central zone of the cavity. Ciliated cells may then propel lymphocytes and secretions into the narrow channels radiating from the uppermost part of the chamber, leaving a cell-free lumen in this region. These cavities may function in sequestering lymphocytes, macrophages and thymic secretions before their exit from the gland.

Animals↗
PubMed2002

[Selenium-based digital radiography of the cervical spine: comparison with screen-film radiography for the depiction of anatomic details].

PURPOSE: To compare selenium-based digital radiography with conventional screen-film radiography of the cervical spine. MATERIALS AND METHODS: In a prospective study X-ray images of the cervical spine were obtained in 25 patients using selenium- based digital radiography and conventional screen-film radiography. All images were clinically indicated. Selenium-based digital radiography and conventional screen-film radiography were used in a randomized order. Four radiologists independently evaluated all 50 examinations for the visibility of 76 anatomic details according to a five-level confidence scale (1 = not visible, 5 = very good visibility). From the evaluation of these anatomic details scores for the upper and middle cervical spine, the cervicothoracic junction and the cervical soft tissues were calculated. The scores for selenium-based digital radiography and conventional screen-film radiography were compared using Wilcoxon's signed rank test. RESULTS: From a total of 15,200 observations (608 per patient) the following scores were calculated for selenium-based digital radiography and for screen-film radiography, respectively: Upper cervical spine 3.88 and 3.94; middle cervical spine 4.60 and 4.48; cervico-thoracic junction 3.64 and 2.62; cervical soft tissue 4.47 and 3.46. The differences between the last two scores were statistically significant (p < 0.05). CONCLUSION: The use of selenium-based digital radiography is superior to conventional screen-film radiography in the depiction of anatomic details of the cervicothoracic junction and the cervical soft tissues.

Cervical Vertebrae↗
PubMedDate not supplied

Analysis of the motor function of the human sphincter of Oddi by endoscopic retrograde cinecholangiography gated by manometry--a report of a case.

Although the motor function of the sphincter of Oddi (SO) has been clearly identified by endoscopic SO manometry (ESOM), the physiologic role of the phasic contractions of the SO remains unsettled in humans. The aim of this study was to correlate SO motor activity measured by ESOM with bile flow characteristics determined by simultaneously recorded endoscopic retrograde cinecholangiography. We investigated a 55-year-old female patient by means of ESOM. During the station pull-through recording, the ESOM catheter was withdrawn into the SO zone and retained there for 15 min. The pressures transmitted by the external transducers and the enlarged video picture of the choledochoduodenal junction from the X-ray fluoroscopic monitor (25 digital pictures/sec) were recorded simultaneously on the computer system with a time-correlated basis. During the analysis without taking note of the cinefluoroscopic events, we selected different manometric periods manually, such as the pressure wave of the SO phasic contraction, no SO phasic activity and the first second of the beginning of the next phasic contraction. Cumulative cinecholangiographic pictures were then constructed by the computer for each period, at a frequency of one frame/sec to create representative sum-of-pictures for each manometric period. By means of the application of manometrically gated cinecholangiography, we succeeded in demonstrating an exact time correlation between the SO systolic and diastolic movements on cinecholangiography and the pressure recording detected by ESOM in humans.

Abdominal Pain↗
PubMed2005

Innervation and connexin isoform expression during diabetes-related bladder dysfunction: early structural vs. neuronal remodelling.

Urinary bladder dysfunction is a major complication in diabetes mellitus and its mechanism has been attributed to altered neurological function (autonomic and/or peripheral neuropathy). Previous studies have demonstrated impaired nerve deficiencies, including either loss of nerve function and/or anatomical loss of neuromuscular nerve terminals. While the phenomenon of diabetes-related neurological injury is well recognised, its pathogenesis is not well understood. Using a well established rat model of diabetes (streptozotocin model), we investigated the prevalence of sympathetic and parasympathetic nerves and relative prevalence of connexin isoforms (gap junction proteins) during diabetes-related bladder dysfunction. Immunohistochemistry and digital image analysis was used to detect the prevalence of postsynaptic neuronal markers, NOS1 and connexin isoform expressions. Immunohistochemistry showed significant increases in tyrosine hydroxylase (marker of sympathetic innervation) and decreased vesicular acetylcholine transporter (marker of parasympathetic innervation), predominantly in the smooth muscle layer, 3 days after diabetes induction, when compared to age-matched controls. Time-dependent and cell-specific decreases in the connexin 43 isoform, but transient increases in connexin 32 and 26, were also observed in diabetic rats vs. controls (p<0.05). These data suggest that selective and time-dependent expression of gap junction proteins and altered prevalence of sympathetic/parasympathetic innervation are early events during diabetes-related bladder dysfunction and remodelling.

Animals↗
PubMed1992

Detection of local recurrence after radical prostatectomy by prostate specific antigen and transrectal ultrasound.

Twenty patients with detectable levels of prostate specific antigen (PSA) after radical prostatectomy with no identifiable distant metastases were evaluated for local recurrence by digital rectal examination and transrectal ultrasound combined with biopsies. Of the patients 9 (45%) were found to have histological evidence of local recurrence at the initial assessment. All 4 patients with an abnormal digital rectal examination had recurrent disease. Transrectal ultrasound displayed abnormalities in 12 of the 20 patients, 7 of whom had positive biopsies. Random biopsies of the vesicourethral junction were performed in 8 patients who had negative ultrasound findings and an unremarkable digital rectal examination, of whom 2 had histological documentation of local recurrence. Complications occurred in 1 patient (5%) who presented with clot retention. We conclude that PSA is an excellent tool for identification of recurrent disease after radical prostatectomy, and transrectal ultrasound guided biopsy is a useful diagnostic approach in patients suspected of local failure, especially when the digital rectal examination is unremarkable.

Antigens, Neoplasm↗
PubMed1998

[Venous system playing a key role in transpetrosal approach].

A case with a large vertebrobasilar junction aneurysm developed a venous infarction in the temporal lobe after an operation using the transpetrosal approach. Although little of the literature has been concerned with venous complications after the transpetrosal approach, the case prompted us to study the venous system as playing a key role in the transpetrosal approach. Analyzing 30 carotid and 15 vertebral angiograms of 15 patients who underwent preoperative cerebral angiography using digital subtraction angiography (DSA), we investigated the venous system near the junction of the superior petrosal sinus, the transverse sinus and the sigmoid sinus (STS junction) which may play a key role in the transpetrosal approach. Drainage pathways of the superficial middle cerebral vein (SMCV) were classified into four types; sphenoparietal, sphenobasal, sphenopetrosal and undeveloped. In the sphenopetrosal type (4/30: 13%), the drainage of SMCV passes back along the floor of the middle fossa to drain into the transverse sinus. The lateral temporal vein (LTV) and the temporobasal vein (TBV) drain into the transverse sinus. The LTV emptied into the transverse sinus either directly (20/30: 67%) or indirectly through the tentorial sinus (10/30: 33%). The entry of the LTV into the transverse sinus (venous point) was usually located in the lateral third of the transverse sinus (14/20: 70%), but sometimes in the middle third (6/20: 30%). The TBV, observed in 8/30 (27%), also often emptied into the tentorial sinus to drain into the transverse sinus. Atresia of a unilateral transverse sinus and a large LTV emptying into the distal sigmoid sinus was observed in 2/15 cases. The venous system near the STS junction may be interrupted by the incision of the tentorium and the middle fossa dura mater and by the retraction of the sigmoid sinus. Since the transpetrosal approach may cause venous complication by compromising the venous system near the STS junction, it is necessary to evaluate of the venous system preoperatively using DSA and to set up a surgical strategy preserving the venous system.

Aneurysm↗
PubMed1991

The effect of alignment errors on bitewing-based bone loss measurements.

Alveolar bone loss measurements made using digitized dental radiographs have been shown to be precise and accurate. We determined the influence of alignment errors introduced when exposing the radiographs on the precision and accuracy of bone loss measurements. Bitewing radiographs of 15 day skulls were obtained using a positioning device (modified after the methods of Duckworth and associates). The sequence of radiographs was taken while the alignment of the main Roentgen beam was systematically varied within a 10 degree cone. Angular displacements were calculated from the digitized radiographs. Space variant digital image enhancement was performed to improve visualization of the cementoenamel junctions and alveolar crests. Corresponding bone loss measurements were made on dry skulls and radiographs. The criterion for truth in these measurements was established by 2 expert observers who measured the skulls with periodontal probes. Radiographic measurements were statistically compared with the criterion using validity coefficients. We found beam positioning errors of up to 10 degrees do not substantively affect alveolar bone loss measurements of mandibular molars taken from enhanced digital images of bitewing radiographs.

Adult↗
PubMed2001

The transmembrane protein occludin of epithelial tight junctions is a functional target for serine peptidases from faecal pellets of Dermatophagoides pteronyssinus.

There have been only a few studies of how allergens cross the airway epithelium to cause allergic sensitization. House dust mite fecal pellets (HDMFP) contain several proteolytic enzymes. Group 1 allergens are cysteine peptidases, whilst those of groups 3, 6 and 9 have catalytic sites indicative of enzymes that mechanistically behave as serine peptidases. We have previously shown that the group 1 allergen Der p 1 leads to cleavage of tight junctions (TJs), allowing allergen delivery to antigen presenting cells. In this study we determined whether HDMFP serine peptidases similarly compromise the airway epithelium by attacking TJs, desmosomes and adherens junctions. Experiments were performed in monolayers of MDCK, Calu-3 or 16HBE14o-epithelial cells. Cell junction morphology was examined by 2-photon molecular excitation microscopy and digital image analysis. Barrier function was measured as mannitol permeability. Cleavage of cell adhesion proteins was studied by immunoblotting and mass spectrometry. HDMFP serine peptidases led to a progressive cleavage of TJs and increased epithelial permeability. Desmosomal puncta became more concentrated. Cleavage of TJs involved proteolysis of the TJ proteins, occludin and ZO-1. This was associated with activation of intracellular proteolysis of ZO-1. In contrast to occludin, E-cadherin of adherens junctions was cleaved less extensively. Although Calu-3 and 16HBE14o-cells expressed tethered ligand receptors for serine peptidases, these were not responsible for transducing the changes in TJs. HDMFP serine peptidases cause cleavage of TJs. This study identifies a second general class of HDM peptidase capable of increasing epithelial permeability and thereby creating conditions that would favour transepithelial delivery of allergens.

Amino Acid Sequence↗
PubMed1988

Altered junctional permeability between cells transformed by v-ras, v-mos, or v-src.

Junctional permeability in normal and transformed NRK cells was quantitatively assessed by microinjecting fluorescent dye into one cell of a pair, digitizing the changes of fluorescence intensity using video analysis techniques, and applying the digital values to a solution of Fick's diffusion equation. We show that this approach reliably estimates the junctional permeance of a cell pair. Cells that are temperature sensitive for transformation were shown to also be temperature sensitive vis-ă-vis junctional permeance. Thus permeance values were reduced approximately 80-90% on transformation by either a mutant Rous sarcoma virus or a mutant Moloney murine sarcoma virus. Cells transformed by wild-type Kirsten sarcoma virus were also shown to possess levels of junctional permeance significantly lower than nontransformed controls. The transformed junctional phenotype could be observed as early as 15 min after shifting to transformation-permissive conditions. Our results suggest that the oncogenes src, ras, and mos exert their effects on NRK cell junctions via converging pathways, of which one may be phosphorylation of junctional proteins.

Animals↗
PubMed1990

Periodontal disease morbidity quantification. II. Validation of alveolar bone loss measurements and vertical defect diagnosis from digital bite-wing images.

Quantitative alveolar bone loss evaluation by digital processing of dental radiographs was performed. More than 20 contrast and edge enhancement techniques were applied to bite-wing radiographs of adult molar teeth and the results subjectively evaluated. Wallis space variant image enhancement was selected as the most promising candidate for improved visualization of the cemento-enamel junctions and alveolar crests. Seventy-three skulls were radiographed, the films digitized, and enhancement performed on the digital images. Alveolar bone loss measurements from skulls (truth) were compared with those from the original radiographs, unprocessed digital images, and enhanced digital images. The average intraclass correlation coefficient for two observers was 0.83 for radiographs, 0.86 for digital images, and 0.91 for enhanced images. The intraclass correlation coefficient between the 2 sets of dry skull measurements made by two additional observers was 0.88. Means and 95% confidence limits were determined for differences between measurements from dry skulls and radiograph-based images. In the worst case for measurements from enhanced images, the mean difference from truth was -0.40 mm with a 95% confidence interval from -0.54 to -0.25 mm. Receiver operating characteristic (ROC) analysis was used to determine the utility of radiograph-based images for the diagnosis of vertical defects. The ability of two observers to diagnose vertical defects on dry skulls was also tested. All methods of vertical defect diagnosis, including the identification of vertical defects on dry skulls, had relatively low diagnostic performance. Image processing technology has considerable potential in periodontal disease studies for quantitative evaluations of alveolar bone height. The diagnosis of vertical defects using current definitions and techniques is problematic, with considerable room for improvement.

Alveolar Bone Loss↗
PubMed1984

The cervicothoracic junction on chest radiograph.

Fractures of the first rib may be detected by indirect signs, including apical extrapleural fluid collection, pneumothorax, and supraclavicular soft tissue mass. Thoracic outlet syndrome represents a complex series of abnormalities that may be clarified utilizing digital subtraction angiography. Major distortions of alignment can produce bony adaptive changes at the cervicothoracic junction simulating intra-spinal canal tumors.

Fractures, Bone↗
PubMed1997

Comparison of alveolar bone loss, alveolar bone density and second metacarpal bone density, salivary and gingival crevicular fluid interleukin-6 concentrations in healthy premenopausal and postmenopausal women on estrogen therapy.

BACKGROUND: Osteoporosis is an age-related metabolic bone disease characterized by decreased mass and increased susceptibility to fracture. The literature suggests a relationship between oral bone loss and skeletal osteoporosis; however, most studies have produced conflicting results. The purpose of this study was to determine if a relationship exists among alveolar bone loss, alveolar bone density, second metacarpal density, salivary and gingival crevicular fluid interleukin 6 (IL-6), and IL-8 concentrations in premenopausal and postmenopausal healthy women receiving estrogen therapy. METHODS: Twenty-eight healthy women (aged 23-78) were evaluated for this study. A vertical bitewing and hand radiographs were taken, and the subjects were evaluated for the presence of active periodontitis. The bitewing and hand radiographs were digitized, and measurements were made from the cemento-enamel junction to the alveolar crest from both arches. Bone density was evaluated in the maxillary and mandibular alveolar process and at the mid-shaft of the second metacarpal. Percent cortical area and the moment of inertia measurements were also determined. Stimulated whole saliva was collected for a 5-min period using a cube of paraffin as a stimulant and was analyzed for total protein by a colorimetric reaction and IL-6 and IL-8 by ELISA. RESULTS: The results of the study showed that postmenopausal women on estrogen therapy had more alveolar bone loss, more missing teeth, and reduced alveolar and second metacarpal bone density than premenopausal women. In addition, postmenopausal women on estrogen therapy had higher salivary IL-6 concentrations than premenopausal women. Alveolar bone densities were also strongly correlated to second metacarpal densities. CONCLUSIONS: The results of the study suggest that changes in alveolar bone density and levels of bone resorptive cytokines in saliva may be secondary to changes in menopausal status. These changes may predispose loss of alveolar bone with resultant loss of teeth.

Adult↗
PubMed1988

The relationship of interradicular width and alveolar bone loss. A radiometric study of a periodontitis population.

Contrasting data exist on the relationship between interproximal width and loss of marginal bone in a periodontitis susceptible population. Reports of clinical observations suggest that the prognosis of teeth with minimal interradicular width should be downgraded in periodontal patients. Others indicate a higher prevalence of intrabony lesions in wider interproximal spaces. Radiographs of 114 adult patients with evidence of bone loss consistent with periodontitis were examined. Measurements of interradicular width and the location of the bone margin from the cementoenamel junction were made at 811 interproximal sites using an optical digitizer at 3X magnification. The relationship between bone loss and interradicular width was investigated. The results indicate that as the interradicular width increases, the interproximal bone margin tends to be in a more apical location. No findings supported the contention that bone in a narrow interradicular space is at greater risk in patients who have had periodontitis.

Adult↗