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1.
Strahlenther Onkol ; 197(11): 953-961, 2021 11.
Article in English | MEDLINE | ID: mdl-34591119

ABSTRACT

PURPOSE: We conducted a patterns-of-care survey on chemoradiation for locoregionally confined anal cancer in Austria to evaluate areas of disagreement and to identify possible targets for further standardization. METHODS: An anonymous questionnaire comprising 38 questions was sent to all Austrian radiation oncology departments. Results were analyzed descriptively and compared to two international guidelines. RESULTS: The response rate was 93%. Work-up generally includes DRE, endoscopy, and cross-sectional imaging of chest/abdomen and pelvis. PET-CT is used by 38%. Screening for HIV and biopsies of suspicious lymph nodes are infrequently used. All centers perform IMRT, mainly with daily IGRT. Median doses to the primary are 54.7 Gy (T1-2) and 59.4 Gy (T3-4). Suspicious nodes receive a boost (median dose 54 Gy), while elective nodal areas are mainly treated with 45-50.4 Gy. Target delineation of elective nodal areas seems generally uniform, although disagreement exists regarding inclusion of the common iliac nodes. No agreement was found for OAR-delineation and dose constraints. Concurrent chemotherapy is mitomycin and 5­FU/capecitabine. Supportive care beyond skin care is infrequently offered. Intensive follow-up is performed for at least 5 years. Treatment of T1N0 shows considerable disagreement. CONCLUSION: We found a high rate of agreement between the centers and concordance with major guidelines. PET-CT, routine HIV testing, and biopsies of suspicious LN seem underrepresented. The largest controversy regarding target volumes concerns inclusion of the common iliac nodes. Prescribed doses are generally in line with the recommendations or higher. OAR delineation, dose constraints, supportive care, and treatment of early anal cancer represent areas for further standardization.


Subject(s)
Anus Neoplasms , Radiation Oncology , Radiotherapy, Intensity-Modulated , Anus Neoplasms/pathology , Anus Neoplasms/radiotherapy , Austria/epidemiology , Humans , Positron Emission Tomography Computed Tomography , Radiotherapy, Intensity-Modulated/methods , Surveys and Questionnaires
2.
Epilepsy Res ; 89(2-3): 349-54, 2010 May.
Article in English | MEDLINE | ID: mdl-20307956

ABSTRACT

PURPOSE: The presence of hippocampal sclerosis (HS) on MRI has a great impact on the clinical evaluation and counselling of patients with temporal lobe epilepsy (TLE) and is considered as a key criterion for the decision to recommend epilepsy surgery. However, neuropathological studies describe evidence of HS in up to 10% of non-epileptic individuals, questioning the impact of this MRI finding in patients with TLE. We evaluated the prevalence of HS on MRI in the general population. METHODS: 100 healthy subjects and 10 patients with TLE due to HS were investigated in a prospective study using a specific protocol for the detection of hippocampal pathology (coronal FLAIR, coronal T2 TSE and a T1 weighted 3D SPGR sequence). RESULTS: HS was detected in none of the healthy subjects (95% confidence interval=0-3.6%), but in all patients. Inter-rater agreement was perfect for presence of HS. Thirty-three subjects had an unilaterally enlarged temporal horn as an isolated secondary criterion for HS and inter-rater agreement was slight for this point. Incidental pathological findings were detected in two patients (2%): one had a low grade astrocytoma (1%), one an aneurysm of the posterior communicating artery (1%). CONCLUSIONS: HS was not diagnosed in healthy subjects, supporting its impact on the evaluation of patients with temporal lobe epilepsy. An unilateral enlarged temporal horn that occurred in one third of the healthy subjects should not be considered as a pathologic finding or even as a marker for HS.


Subject(s)
Epilepsy, Temporal Lobe/diagnosis , Hippocampus/pathology , Magnetic Resonance Imaging/methods , Adult , Epilepsy, Temporal Lobe/pathology , Female , Functional Laterality , Humans , Male , Prevalence , Prospective Studies , Sclerosis
3.
J Vet Intern Med ; 22(6): 1444-6, 2008.
Article in English | MEDLINE | ID: mdl-19000254

ABSTRACT

BACKGROUND: Ventricular tachyarrhythmias occur in association with cardiac and extracardiac disorders in many species of animals, but information identifying concurrent disorders in cats with such arrhythmias is scarce. METHODS: We investigated coexisting diseases by retrospectively evaluating medical records of cats with ventricular tachyarrhythmias seen during a 51-month period at 1 institution. For comparative purposes, we evaluated records of dogs with similar arrhythmias during the same time period. All cats and dogs had premature ventricular complexes, accelerated idioventricular rhythm, ventricular tachycardia, or some combination of these arrhythmias, and all had undergone echocardiography during the same visit that led to the diagnosis of ventricular tachyarrhythmia. RESULTS AND CONCLUSIONS: Most (102/106; 96%) cats had at least 1 echocardiographically apparent abnormality concurrent with ventricular tachyarrhythmias. Ventricular tachyarrhythmias in cats were most commonly associated with myocardial disease (eg, left ventricular concentric hypertrophy [n = 66], restrictive or unclassified cardiomyopathy [n = 17], and dilated cardiomyopathy [n = 6]). When comparing dogs and cats that had ventricular tachyarrhythmias and were diagnosed on the same clinical service of the same institution, an echocardiographically apparent cardiac lesion was seen more often in cats (102/106, 96%) than in dogs (95/138, 69%) (P < .001).


Subject(s)
Cat Diseases/pathology , Tachycardia, Ventricular/veterinary , Animals , Cats , Myocardium/pathology , Retrospective Studies , Tachycardia, Ventricular/pathology
4.
Hear Res ; 239(1-2): 12-9, 2008 May.
Article in English | MEDLINE | ID: mdl-18316166

ABSTRACT

The transformation of head-movements into neural signals represents a multi-stage process. It depends on orientation and movement of the head, the geometry and mechanics of the vestibular sensors, and the ensuing processing of the peripheral vestibular signals. While this process is well understood for the semicircular canals, where each canal transduces the angular velocity in the corresponding canal plane, the contributions of the individual otoliths, our linear acceleration sensors, are still under debate. This is in part due to the complex geometrical structure of the otoliths. To improve our understanding of the otoliths, we have developed a new technique to visualize otolith function: using measured 3D-shapes of human otoliths and the observed 2D patterns of hair cell orientation over the epithelia, morphological polarization vectors are predicted. To visualize the geometric distribution of these vectors, we have created distribution plots which indicate the density of hair cell polarization vectors for the different directions. In many respects, our results closely agree with earlier recordings of polarization vectors of vestibular afferents in squirrel monkeys: for example, hair cells on the saccule do not cover the sagittal plane equally, but show a strong concentration in the dorso-ventral directions. Some discrepancies exist in the density distribution of otolith, which could provide valuable information for future anatomical investigations of the otoliths.


Subject(s)
Hearing , Otolithic Membrane/pathology , Algorithms , Animals , Biomechanical Phenomena , Epithelium/metabolism , Hair Cells, Auditory , Haplorhini , Humans , Imaging, Three-Dimensional , Mammals , Models, Biological , Movement , Otolithic Membrane/physiology
5.
Article in English | MEDLINE | ID: mdl-18002608

ABSTRACT

The paper describes a first aid medical sensor system that is able to detect pulse and respiration. According to an opinion poll 79% of unexperienced first aiders were looking forward to use a system that supports them in first aid situations. Such a device has to be reliable and available in everyday use (e.g. as a keychain or in a first-aid kit). Therefore we investigated a single point sensor that is able to detect both respiration and blood flow at the same point of the body, for instance on the neck. Compared to ECG-derived methods absent pulse due to pulseless electrical activity (PEA) will be recognized as such. Tests have shown that the sensor can also be used to detect deglutition and other body motion sequences.


Subject(s)
First Aid/methods , Pulse , Respiration , Electrocardiography/methods , Humans , Larynx/physiology , Male , Regional Blood Flow
7.
Histopathology ; 45(1): 65-72, 2004 Jul.
Article in English | MEDLINE | ID: mdl-15228445

ABSTRACT

AIMS: Ameloblastoma is an odontogenic neoplasm characterized by local invasiveness and recurrence. In this study we analysed the role played by matrix metalloproteinases (MMPs) in the local invasiveness of ameloblastoma. We also attempted to establish a relationship between the presence of MMPs and the proliferative activity of ameloblastoma cells. METHODS AND RESULTS: Immunohistochemistry was carried out to detect different MMPs in formalin-fixed paraffin-embedded samples of human ameloblastoma. Immunohistochemistry, however, does not establish whether a given MMP is latent or active. To address this point, we carried out biochemical methods, namely zymography and Western blotting. Our results showed expression of latent and active forms of MMPs 1, 2 and 9 in ameloblastoma. These enzymes may digest bone matrix and release mitogenic factors, which would increase tumour proliferation. This possibility prompted us to study the proliferation of ameloblastoma cells located in close proximity to bone. Silver-stained nucleolar organizer region morphometry revealed that ameloblastoma cells in the vicinity of bone show increased proliferation, when compared with controls. CONCLUSIONS: Our results suggest an interdependent mechanism involving MMPs and proliferation of ameloblastoma cells, which may contribute to the local invasiveness of this tumour.


Subject(s)
Ameloblastoma/pathology , Jaw Neoplasms/pathology , Matrix Metalloproteinases/metabolism , Ameloblastoma/enzymology , Blotting, Western , Cell Proliferation , Humans , Immunohistochemistry , Jaw Neoplasms/enzymology , Matrix Metalloproteinase 1/metabolism , Matrix Metalloproteinase 2/metabolism , Matrix Metalloproteinase 9/metabolism , Neoplasm Invasiveness
8.
Oral Oncol ; 40(6): 585-90, 2004 Jul.
Article in English | MEDLINE | ID: mdl-15063386

ABSTRACT

Adenoid cystic carcinoma (ACC) of salivary glands is characterized by a high rate of local recurrences, neurotropism and metastasis. ACC long-term survival rate is not promising. Thus, different chemotherapeutical approaches had been proposed for this neoplasm, including apoptosis induction by different drugs. This work evaluates the efficacy of Brefeldin-A (BFA), a potent apoptosis inducer, on ACC cultured cells (CAC2 cell line). CAC2 cells were treated with a 375 microM BFA solution in serum-free medium during 18 h. CAC2 cells grown in DMEM supplemented with 10% fetal bovine serum served as controls. Apoptotic cell recognition and counting were carried out through Hoechst staining. Transmission electron microscopy and immunofluorescence assessed the effect of BFA on CAC2 cells phenotype. Treated cultures showed a high apoptotic index presenting +/-30% of cells in evident apoptosis, when compared to controls. Apoptotic CAC2 cells also exhibited different alterations such as cytoplasmic vesicles formation and mitochondrial changes. Cultured ACC cells are strongly susceptible to apoptosis induction under BFA treatment, which may constitute a promising tool in further chemotherapeutical approaches.


Subject(s)
Apoptosis , Brefeldin A/pharmacology , Carcinoma, Adenoid Cystic/physiopathology , Protein Synthesis Inhibitors/pharmacology , Salivary Gland Neoplasms/physiopathology , Carcinoma, Adenoid Cystic/ultrastructure , Fluorescent Antibody Technique/methods , Golgi Apparatus/immunology , Golgi Apparatus/pathology , Humans , Microscopy, Electron/methods , Salivary Gland Neoplasms/ultrastructure , Tumor Cells, Cultured
9.
Biol Cybern ; 90(3): 165-75, 2004 Mar.
Article in English | MEDLINE | ID: mdl-15052480

ABSTRACT

To investigate the dynamic effects of external forces on the displacement of the otolith membrane and subsequent neuronal responses of otoliths, we performed numerical analyses of otolith membrane displacements. In these studies we included the full geometry of the human otolith maculae, including their 3D curvature. The first part focuses on mechanical aspects of the otolith membrane. While it was found that the mechanical coupling of distant parts of the otolith membrane is only weak, these simulations indicate that curvature may have considerable local effects on displacements. They further suggest that the movements of the otoconia, embedded in the interotoconial matrix, show a resonance in a range between 100 and 2000 Hz. In the second part of the article we also investigate the tonic-phasic responses in the vestibular nerve emanating from hair cells in the striola region. Small head tilts away from head upright position are used. The simulations indicate that the direction of head tilt is coded in characteristic response patterns along the striola.


Subject(s)
Models, Neurological , Neurons/physiology , Nonlinear Dynamics , Otolithic Membrane/physiology , Computer Simulation , Head Movements/physiology , Humans , In Vitro Techniques , Nystagmus, Optokinetic/physiology , Physical Stimulation/methods , Saccule and Utricle/cytology , Signal Detection, Psychological , Vestibular Nuclei/physiology
10.
Oral Oncol ; 40(5): 483-9, 2004 May.
Article in English | MEDLINE | ID: mdl-15006619

ABSTRACT

In a previous paper, we demonstrated that laminin-1 and its derived peptide SIKVAV modulates the morphology of an adenoid cystic carcinoma cell line (CAC2 cells). Light microscopy of CAC2 cells grown in three-dimensional preparations of SIKVAV-enriched laminin-1 showed the presence of pseudocystic spaces. Pseudocysts are hallmarks of adenoid cystic carcinoma in vivo. We hypothesized that these pseudocystic spaces could be due to the protease-inducing/activating role of SIKVAV. Thus, we studied the presence of matrix metalloproteinases (MMPs) in CAC2 cells treated either by laminin-1 or by SIKVAV-enriched laminin-1. Immunohistochemistry and zymography suggested that SIKVAV enhanced the secretion of MMP-2 and MMP-9 in CAC2 cells. We propose that SIKVAV induces pseudocystic formation probably through the secretion of MMPs 2 and 9.


Subject(s)
Carcinoma, Adenoid Cystic/enzymology , Laminin/pharmacology , Matrix Metalloproteinases/analysis , Oligopeptides/pharmacology , Salivary Gland Neoplasms/enzymology , Carcinoma, Adenoid Cystic/pathology , Cell Line, Tumor/drug effects , Culture Media , Cytoplasm/chemistry , Extracellular Space/chemistry , Humans , Immunohistochemistry/methods , Laminin/metabolism , Matrix Metalloproteinase 2/analysis , Matrix Metalloproteinase 9/analysis , Oligopeptides/metabolism , Salivary Gland Neoplasms/pathology
11.
Oral Oncol ; 40(1): 36-42, 2004 Jan.
Article in English | MEDLINE | ID: mdl-14662413

ABSTRACT

We have demonstrated that the basement membrane regulates the myoepithelioma. We are now studying the effect of laminin, a basement membrane protein, in the morphology of a cell line (M1) derived from human salivary gland plasmacytoid myoepithelioma. These cells were grown inside a three-dimensional preparation of laminin-1. Phenotype differences were assessed by light and transmission electron microscopy. In addition, we analysed the effect of a molecular domain of laminin-1, the peptide SIKVAV, on M1 cells. This peptide was chosen because it is effective in cell proliferation and differentiation. M1 cells grown inside laminin-1 were mostly plasmacytoid-like, while cells treated by SIKVAV showed light and electron microscopic features of typical plasmacytoid cells. This peptide also modulated smooth-muscle actin expression in M1 cells. We demonstrated that laminin-1 and its derived peptide SIKVAV morphoregulates myoepithelioma cells in culture.


Subject(s)
Laminin/pharmacology , Myoepithelioma/pathology , Oligopeptides/pharmacology , Salivary Gland Neoplasms/pathology , Cell Line, Tumor , Humans , Immunohistochemistry , Microscopy, Electron , Muscle, Smooth/metabolism
12.
Int Endod J ; 36(6): 404-10, 2003 Jun.
Article in English | MEDLINE | ID: mdl-12801287

ABSTRACT

AIM: To simultaneously analyse the expression of type I collagen, osteonectin and bone sialoprotein (BSP) in human dental pulp of different ages. METHODOLOGY: Cultured dental pulp fibroblasts (FP1 cell line), pulps from dental germs with incomplete root formation (n = 4) and pulps of erupted teeth with total root formation (n = 4) were used. Bone proteins were searched by immunohistochemistry and immunofluorescence using polyclonal antibodies and compared among the three groups assessed. RESULTS: Immunohistochemistry detected the three proteins in dental pulp tissue, as it labelled extracellular matrix, predentine and odontoblasts. The BSP label was weaker, when compared to both type I collagen and osteonectin. The presence of type I collagen was more evident in pulps from erupted teeth, when compared to germ dental pulps. On the other hand, a strong expression of osteonectin in germ dental pulps was observed. CONCLUSIONS: Regardless of the degree of maturation, dental pulps present type I collagen, osteonectin and BSP in the extracellular matrix (ECM) and in the odontoblastic layer. Thus, the results suggest that these proteins are related to the production and mineralization of dentine.


Subject(s)
Collagen Type I/analysis , Dental Pulp/cytology , Osteonectin/analysis , Sialoglycoproteins/analysis , Cell Line , Dentin/cytology , Extracellular Matrix/chemistry , Fibroblasts/cytology , Fluorescent Antibody Technique, Direct , Humans , Immunohistochemistry , Integrin-Binding Sialoprotein , Odontoblasts/cytology , Tooth Eruption , Tooth Germ/cytology , Tooth, Unerupted/pathology
13.
Oral Oncol ; 39(5): 453-8, 2003 Jul.
Article in English | MEDLINE | ID: mdl-12747969

ABSTRACT

Epithelial-myoepithelial carcinoma of the salivary gland is a rare, low-grade, neoplasm, composed of ductal and myoepithelial cells. We present two novel cell lines, which have been characterised by immunofluorescence, derived from an epithelial-myoepithelial carcinoma of the parotid gland. A resected mass of the parotid gland was diagnosed as an epithelial-myoepithelial carcinoma by routine histological examination. Part of the specimen was labelled with a panel of antibodies confirming the tumour type. The other part was finely minced and the explants were incubated in DMEM supplemented with penicillin and streptomycin, at 37 degrees C in a humidified 5% CO(2) atmosphere. Two cell types were identified by immunofluorescence-a small cobblestone cell, positive for AE1/AE3 and p53, and a polyhedral cell, positive for vimentin, smooth muscle markers and S-100. Herein two cell lines are presented in order to open up possibilities of new studies and a discussion of the events that culminate in this bimodal neoplasm is also performed.


Subject(s)
Carcinoma/pathology , Nuclear Proteins , Parotid Neoplasms/pathology , Tumor Cells, Cultured/pathology , Adult , Carcinoma/chemistry , Cell Culture Techniques/methods , Female , Humans , Keratins/analysis , Neoplasm Proteins/analysis , Parotid Neoplasms/chemistry , Proto-Oncogene Proteins/analysis , Proto-Oncogene Proteins c-mdm2 , Tumor Cells, Cultured/chemistry , Tumor Suppressor Protein p53/analysis
14.
Hear Res ; 173(1-2): 29-42, 2002 Nov.
Article in English | MEDLINE | ID: mdl-12372633

ABSTRACT

We have performed a finite element simulation of realistic displacements of otolith membranes by static linear accelerations. The simulations were based on accurate measurements of the surfaces of human utricular and saccular maculae, which indicate a clear curvature of these surfaces. The results show that this curvature, a feature probably found in all mammals, has no effect on the mechanics of the structure as a whole since the elastic coupling in the otolith membrane is insufficient. Hair cell excitations on any place of the macula are only affected by the local orientation of the macula with respect to acceleration. Based on the displacements of the otolith membrane, we also calculated the induced activation patterns on the otolith epithelia. These patterns provide for the first time a complete image of peripheral otolith activity. The individual activation patterns at selected locations on the macula correspond well with single cell recordings of actual peripheral otolith neurons.


Subject(s)
Head/physiology , Models, Biological , Orientation/physiology , Otolithic Membrane/physiology , Cell Polarity , Hair Cells, Auditory/physiology , Humans
15.
J Rehabil Res Dev ; 38(5): 591-7, 2001.
Article in English | MEDLINE | ID: mdl-11732836

ABSTRACT

The purpose of this study was to assess the effects of applying transcutaneous electrical stimulation to paralyzed abdominal muscles during pulmonary function testing (PFT) of individuals with spinal cord injury (SCI). Ten male subjects with anatomical level of SCI between C5-T7 were studied. Subjects performed PFTs with and without electrical stimulation delivered to the abdominal muscles. Subjects with the lowest percentage of predicted expiratory volumes and flows demonstrated the greatest improvement when electrical stimulation was delivered during forced expiration. The overall increases seen in percent of predicted for the study sample were 23 percent for forced vital capacity (FVC), 16 percent for forced expiratory flow in 1 s (FEV1), and 22 percent for peak expiratory flow rate (PEF). Contractions of paralyzed expiratory muscles in response to electrical stimulation during the performance of PFT maneuvers can significantly improve FVC, FEV1, and PEF in some individuals with SCI.


Subject(s)
Abdominal Muscles , Spinal Cord Injuries/rehabilitation , Transcutaneous Electric Nerve Stimulation , Abdominal Muscles/physiology , Adult , Aged , Humans , Least-Squares Analysis , Male , Middle Aged , Respiratory Function Tests
16.
Virchows Arch ; 439(4): 571-8, 2001 Oct.
Article in English | MEDLINE | ID: mdl-11710645

ABSTRACT

We have already demonstrated that a reconstituted basement membrane (Matrigel) is a key modulator of morphogenetic changes and cytodifferentiation of pleomorphic adenoma cells in culture. Myoepithelioma is considered to be a neoplasm closely related to pleomorphic adenoma and should experience similar induction processes. Thus, the aim of this study was to investigate whether Matrigel would influence myoepithelioma cells. We used a cell line derived from a human salivary gland plasmacytoid myoepithelioma (M1 cells) grown in a three-dimensional preparation of Matrigel. Phenotype differences were assessed using conventional light microscopy technique (haematoxylin and eosin) and phase and differential interference contrast (Nomarski). Immunofluorescence was carried out to detect smooth-muscle actin, laminin and type-IV collagen. M1 cells exhibited all proteins studied, showing a myoepithelial differentiation. M1 cells grown inside Matrigel presented morphological changes and changes in smooth-muscle actin status. By growing M1 cells inside Matrigel, it was possible to reproduce the tumour architecture with no duct-like structures. Based on our findings, we suggest that myoepithelioma would be derived from a cell with a commitment to myoepithelial differentiation. We also suggest that the mechanical properties of the matrix environment will likely regulate smooth-muscle actin expression in myoepithelioma.


Subject(s)
Biocompatible Materials/metabolism , Collagen , Drug Combinations , Extracellular Matrix/metabolism , Laminin , Myoepithelioma/pathology , Proteoglycans , Salivary Gland Neoplasms/pathology , Actins/analysis , Actins/metabolism , Collagen Type IV/analysis , Collagen Type IV/metabolism , Culture Media , Fluorescent Antibody Technique, Direct , Humans , Laminin/analysis , Laminin/metabolism , Myoepithelioma/chemistry , Myoepithelioma/metabolism , Salivary Gland Neoplasms/chemistry , Salivary Gland Neoplasms/metabolism , Tumor Cells, Cultured
17.
Oral Oncol ; 37(8): 638-42, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11590073

ABSTRACT

Adenoid cystic carcinoma of salivary glands is characterised by aggressive behaviour, high rate of local recurrences, neurotropism and late metastasis. In a previous work we demonstrated that adenoid cystic carcinoma cultured cells (CAC2 cells) expressed N-CAM. It was suggested that this expression, modulated by extracellular matrix, would be correlated to cell movement. The aim of our study was to verify whether CAC2 cells presented invasion capacity. Moreover, we tested whether the neural adhesion molecule (N-CAM) would participate in this process. CAC2 cells were either previously treated, or not (control), with a monoclonal antibody against N-CAM. Invasion assays were carried out using a modified Boyden chamber (Transwell chamber). CAC2 cells (10(5)) were dispensed into Transwell upper chamber on the top of Matrigel coated filter. The cells that invaded the filters in the first 8 h were counted under light microscopy, yielding data for the invasion rates (%). Control CAC2 cells presented an invasion rate of 5.28+/-0.04%. The invasion rate raised to 6.53+/-0.2% when N-CAM was blocked with monoclonal antibody. N-CAM impaired the adenoid cystic carcinoma cell invasion in vitro. Therefore, we suggest an anti-invasive role for N-CAM in adenoid cystic carcinoma.


Subject(s)
Carcinoma, Adenoid Cystic/pathology , Neural Cell Adhesion Molecules/physiology , Parotid Neoplasms/pathology , Analysis of Variance , Antibodies, Monoclonal/immunology , Cell Count , Fluorescent Antibody Technique , Humans , Microscopy, Fluorescence , Neoplasm Invasiveness , Tumor Cells, Cultured
18.
Biochem Pharmacol ; 62(4): 425-9, 2001 Aug 15.
Article in English | MEDLINE | ID: mdl-11448451

ABSTRACT

The cellular extrusion of guanosine 3',5'-cyclic monophosphate (3',5'-cGMP) is a unidirectional ATP-dependent process that is inhibited by probenecid, a non-selective transport inhibitor of organic anions. In the present study, various cGMP analogues were tested for their ability to inhibit 3',5'-cGMP efflux and stimulate the cGMP-selective ATPase in human erythrocytes. The difference in uptake of 1 microM [(3)H]3',5'-cGMP to inside-out vesicles in the presence and absence of 1 mM ATP at 37 degrees was defined as active transport. Two ATP-dependent components were detected for unlabelled 3',5'-cGMP (0.01--100 microM) with respective K(i) of 1.3 +/- 0.2 and 280 +/- 50 microM (mean +/- SEM, N = 3). The high-affinity transport was inhibited by the analogues with a typical pattern: Rp-monophosphorothioate guanosine 3',5'-cyclic monophosphate (Rp-cGMPS) > 3',5'-cGMP > 2'-O-monobutyryl guanosine 3',5'-cyclic monophosphate (O-mb-cGMP) approximately N(2)-monobutyryl guanosine 3',5'-cyclic monophosphate (N-mb-cGMP) > or = N(2),2'-O-dibutyryl guanosine 3',5'-cyclic monophosphate (Db-cGMP) approximately 8'-bromo guanosine 3',5'-cyclic monophosphate (Br-cGMP) approximately Guanosine 2',3'-cyclic monophosphate (2'3'-cGMP) > Sp-monophosphorothioate guanosine 3',5'-cyclic monophosphate (Sp-cGMPS). A concentration-dependent inhibition was found for the low-affinity transport, but no distinct order of potency was identified. Analysis according to Lineweaver--Burk of active [(3)H]3',5'-cGMP transport (0.2--2 microM) gave a K(m) value of 1.5 +/- 0.1 microM (mean +/- SEM, N = 3). The presence of 10 microM cGMP analogues did not change the ordinate intercept, but made the slopes steeper with a typical order: Rp-cGMPS > 3',5'-cGMP > N-mb-cGMP approximately O-mb-cGMP approximately db-cGMP approximately 8-Br-cGMP > 2',3'-cGMP > Sp-cGMPS. Only 3',5'-cGMP and 2',3'-cGMP were able to activate the cGMP-specific ATPase, 640 +/- 200% and 430 +/- 160% (mean +/- SEM, N = 5) above basal levels, respectively. The present data show that the binding is less selective than ATPase activation of the cellular cGMP transport system.


Subject(s)
Adenosine Triphosphatases/metabolism , Cell Membrane/drug effects , Cyclic GMP/pharmacology , Cell Membrane/enzymology , Cell Membrane/metabolism , Cyclic GMP/analogs & derivatives , Enzyme Activation , Erythrocytes/drug effects , Erythrocytes/metabolism , Humans , In Vitro Techniques , Tritium
19.
Oral Oncol ; 37(3): 326-31, 2001 Apr.
Article in English | MEDLINE | ID: mdl-11287290

ABSTRACT

We present four new cases of verruciform xanthoma (VX) in the oral mucosa and review the literature. Clinical, histological, and immunohistochemical features of four new cases of VX were analysed together with cases found in a review of the literature. Expression of CD-68 was studied by immunohistochemistry. Only 162 cases were reported in the oral mucosa. Ninety were males (55.5%) and 72 were females (44.5%). Mean age was 44.9 years. The majority of cases occurred in masticatory mucosa (69.7%). Our cases exhibited papillary or verrucous proliferation of squamous epithelium associated with hyperparakeratosis and with numerous foamy cells confined to the lamina propria papillae. Foamy cells were positive to CD-68 antibody, showing a macrophagic nature. VX is a rare benign lesion, and is probably inflammatory. However, its aetiology and pathological mechanisms remain unknown.


Subject(s)
Mouth Diseases/pathology , Mouth Mucosa/pathology , Xanthomatosis/pathology , Adult , Antigens, CD/analysis , Antigens, Differentiation, Myelomonocytic/analysis , Biomarkers/analysis , Foam Cells/chemistry , Foam Cells/pathology , Humans , Immunohistochemistry , Macrophages/immunology , Macrophages/pathology , Male , Middle Aged , Mouth Diseases/immunology , Mouth Mucosa/immunology , Xanthomatosis/immunology
20.
Am J Dent ; 14(6): 373-7, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11949797

ABSTRACT

PURPOSE: To determine the tensile bond strength of composite repairs applied to Artglass using different surface treatments. MATERIALS AND METHODS: Blocks of Artglass were embedded in PVC cylinders with self-cure acrylic resin and divided into 18 groups according to the surface treatment. Three mechanical treatments and six chemical treatments were combined. Mechanical treatments were: sandpaper, diamond bur and microetch. Chemical treatments were: Prime & Bond 2.1 (PB) only, phosphoric acid+PB, hydrofluoric acid (applied for 1 or 3 minutes) +PB, Artglass Liquid only and silane+PB. After surface treatment, a composite truncated cone (Charisma, shade A3) was built. Tensile test was carried out after 24 hrs storage in distilled water at 37 degrees C. Failure mode was assessed using a x 10 stereomicroscope. Artglass surfaces treated mechanically and their combination with phosphoric acid and hydrofluoric acid were analyzed by scanning electron microscopy (SEM). RESULTS: Two-way ANOVA revealed that there was no statistical difference in bond strength among the three mechanical treatments used, except for the groups where Artglass Liquid and silane were used. The use of phosphoric acid and Artglass Liquid did not improve the bond strength of the specimens compared to the groups where only PB was applied, regardless of the mechanical treatment. Hydrofluoric acid treatment for 1 and 3 minutes reduced the bond strength significantly compared to the other chemical treatments. The association of silane with microetching resulted in a statistically higher bond strength compared to all the other experimental groups. SEM analysis showed that the application of phosphoric acid failed to promote changes in mechanically treated samples. On the other hand, when hydrofluoric acid was associated to either diamond bur or microetching, the topography created by the mechanical treatment was at least partially destroyed.


Subject(s)
Composite Resins , Dental Bonding/methods , Dental Prosthesis Repair , Dental Restoration, Permanent/methods , Glass Ionomer Cements , Inlays , Silicate Cement , Air Abrasion, Dental , Analysis of Variance , Materials Testing , Silanes , Statistics, Nonparametric , Surface Properties , Tensile Strength
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