bluuebunny/crossref_metadata_2025_split huggingface dataset:
Transforming Growth Factor Beta Induces Urokinase Receptor Expression in Cultured Retinal Pigment Epithelial Cells
Authors: Sirén Vappu , Myöhänen Heli , Vaheri Antti , Immonen Ilkka 
Published: April 2003

The effect of transforming growth factor-β<sub>1</sub> (TGF-β<sub>1</sub>) and interferon-γ (IFN-γ) was studied on urokinase receptor (uPAR) expression of cultured human retinal pigment epithelial (RPE) cells. Human RPE cells were incubated with 1, 5 or 10 ng/ml of TGF-β<sub>1</sub> or with 10, 100 or 1,000 IU/ml of IFN-γ to measure total cellular uPAR protein and released uPAR by enzyme immunoassay. uPAR at cell surface was measured by flow cytometric analysis at 8, 12, 24 and 48 h. uPAR mRNA levels were assayed by Northern blotting at 2, 6, 12 and 24 h. The increase in uPAR gene expression in RPE cells exposed to TGF-β<sub>1</sub> paralleled enhanced uPAR level at the cell surface and in conditioned medium. TGF-β appeared to induce also membrane-bound uPA activity and the release of active plasminogen activator inhibitor-1, indicating that TGF-β has the potential to regulate plasminogen activation at the RPE cell surface. The increase in uPAR gene expression by IFN-γ did not seem to translate into the protein level. We conclude that TGF-β regulates the pericellular proteolysis in RPE cells by increasing uPAR expression.
Epitheliomesenchymal Transdifferentiation of Cultured RPE Cells
Authors: Lee Sung-Chul , Kwon Oh-Woong , Seong Gong-Je , Kim Soon-Hyun , Ahn Jae-Eun , Kay Eun-Duck P. 
Published: April 2003

Retinal pigment epithelium (RPE) cells of the proliferative vitreoretinopathy (PVR) membrane take on the shape of fibroblasts and participate in fibrosis, thus deviating from the character of epithelial cells. This study was undertaken to evaluate RPE cell transdifferentiation in vitro. During the culture of porcine RPE cells, primary and 10th-passaged RPE cells were investigated for cell growth in response to transforming growth factor (TGF) β<sub>2</sub>, change of phenotype and amount in collagen synthesis as well as expression of α-smooth-muscle actin (α-SMA). TGF-β<sub>2</sub> inhibited the proliferation of the primary cultures of RPE cells in a dose-dependent manner, while the spindle-shaped 10th-passaged RPE cells were not inhibited by TGF-β<sub>2</sub>. The 10th-subcultured cells did not show much difference in the quality of collagen synthesis, other than type VIII collagen which was not produced. Collagen synthesis was dose-dependently stimulated by TGF-β<sub>2</sub>. The stimulation by TGF-β<sub>2</sub> in the 10th-passaged RPE cells was much greater than in primary RPE cells. The 10th-subcultured RPE cells produced substantial α-SMA compared to α-SMA production by primary RPE cells. These results were also observed by confocal laser microscopy. These findings indicated that RPE metaplasia resulting in a change of biological cell behavior might be a necessary predisposing step in the development of PVR.
Inhibitory Effect of 2′-O-Benzoylcinnamaldehyde on Vascular Endothelial Cell Proliferation and Migration
Authors: Park Ji-Young , Kwon Byoung-Mog , Chung Sung-Kun , Kim Jae-Ho , Joo Choun-Ki 
Published: April 2003

<i>Purpose:</i> To evaluate the inhibitory effect of the farnesyl transferase inhibitor 2′-O-benzoylcinnamaldehyde (CB 2′-ph) on proliferation and migration of vascular endothelial cells. <i>Methods:</i> Bovine lens epithelial cells, bovine corneal endothelial cells, bovine keratocytes, bovine aortic endothelial cells (BAECs) and human umbilical vein endothelial cells (HUVECs) were treated with CB 2′-ph to determine its cell type specificity and antiproliferative effect. For inhibition of vascular endothelial cell growth factor (VEGF)- or basic fibroblast growth factor (bFGF)-induced proliferation of HUVECs, these cells were treated with various concentrations of CB 2′-ph. To assess the proliferation, MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl-tetrazolium bromide) assay was used. The migration assay was also performed to determine the effect of CB 2′-ph on HUVECs. The distance of HUVEC outgrowth was measured from the scraped edge of a monolayer after treatment with CB 2′-ph concentrations of 0, 1.5 and 2.5 µg/ml for 24, 48 and 72 h. <i>Results:</i> The CB 2′-ph had an inhibitory effect on all tested types of cell proliferation but only HUVEC and BAEC proliferation was specifically inhibited in a dose-dependent manner. In addition, CB 2′-ph inhibited VEGF- or bFGF-induced proliferation and migration of HUVECs in a dose-dependent manner. <i>Conclusions:</i> These results indicate that CB 2′-ph, a farnesyl transferase inhibitor is thought to be an effective inhibitor of vascular endothelial cell proliferation and migration.
Role of Aprotinin in the Management of Experimental Fungal Keratitis
Authors: Biswas Nihar R. , Das Hrishikesh , Satpathy Gita , Mohanty Srujana , Panda Anita 
Published: April 2003

In an experimentally induced <i>Aspergillus fumigatus </i>fungal keratitis in 20 rabbits, aprotinin, an antiplasmin agent, was studied to find out its role as an adjuvant when given along with other established antifungal agents like natamycin and fluconazole. The 20 rabbits included in this study were randomly divided into four equal treatment groups. Once the ulcer was produced after intrastromal injection of 0.03 ml of <i>A. fumigatus</i> (5.5 × 10<sup>4</sup> spores/ml), different drugs/agents in combination were used in a randomized manner. These were natamycin (5%) + placebo, natamycin + aprotinin (40 IU/ml), fluconazole (0.3%) + placebo and fluconazole + aprotinin. The rabbits were followed up every day to note the signs of healing which included subsidence of corneal infiltration, disappearance of stromal abscess and subsidence of corneal oedema till complete healing. Results showed that the average healing time was 28.2, 28.4, 49.8 and 49.0 days for natamycin + placebo, natamycin + aprotinin, fluconazole + placebo and fluconazole + aprotinin, respectively. It suggests that aprotinin as an adjuvant has no definite role in the management of fungal keratitis. The plasminogen activator-plasmin system which is inhibited by aprotinin may not be the pathway through which filamentous fungi like <i>A. fumigatus</i> cause tissue destruction.
The Cerebral Neurobiology of Anxiety, Anxiety Displacement, and Anxiety Denial
Authors: Gottschalk Louis A. , Fronczek Janny , Abel Lennart , Buchsbaum Monte S. , Fallon James H. 
Published: April 2003

<i>Background:</i> Previous studies examining the relationship of anxiety scores, derived from the content analysis of speech of normal individuals, have revealed that the anxiety scores occurring in the dreams associated with rapid eye movement (REM) sleep are significantly correlated with localized cerebral glucose metabolic rates assessed by positron emission tomography (PET) scanning. These significant intercorrelations occur in different cerebral areas when the anxiety scores are obtained from mental experiences reported during non-REM sleep or during wakeful silent mentation. <i>Objective:</i> The purpose of the present study was to examine the intercorrelations found between anxiety attributed to the self, anxiety-displacement, and anxiety denial measured from computerized content analysis of 5-min verbal reports of subjective thoughts and feelings obtained from wakeful normal subjects and localized cerebral glucose metabolic rates during PET scanning. <i>Methods:</i> The subjects were 10 wakeful young males. Their anxiety scores were derived from computerized content analysis of 5-min reports they gave of their subjective thoughts, feelings and fantasies during a 30-min period following an intravenous injection of F D-deoxyglucose (FDG). The subjects were moved 32–45 min after this injection to obtain a PET scan, which records all of the localized cerebral glucose metabolic rates during the 30 min following the FDG injection. <i>Results:</i> Significant intercorrelations of localized cerebral glucose metabolic rates with the scores of self-anxiety, anxiety displacement, and anxiety-denial were found in dissimilar cerebral locations depending on the type of anxiety involved. The significant correlations occurred in brain regions known to be associated with the functions of emotions, cognition, memory, and vision. <i>Conclusions:</i> Specific combinations of cerebral areas, based on glucose metabolic rates, appear to distinguish and be associated with different verbal expressions of anxiety. Replication of this preliminary research will be carried out.
Effect of Body Position on Arterial Oxygen Tension in the Elderly
Authors: Hardie Jon A. , Mørkve Odd , Ellingsen Ivar 
Published: April 2003

<i>Background:</i> It is well known that body position can have an effect on gas exchange though the magnitude of this effect has not been studied thoroughly in the elderly. <i>Objectives:</i> This study analyzes the effect body position change has on arterial oxygen tension (PaO<sub>2</sub>) and arterial carbon dioxide tension (PaCO<sub>2</sub>) in healthy elderly. <i>Methods:</i> We tested 46 ‘lung-healthy’ elderly, including 30 women and 16 men, 67–88 years of age. Blood was drawn from the radial artery first in the sitting position and subsequently in the supine position. Spirometry was performed. <i>Results:</i> Mean (SD) sitting PaO<sub>2</sub> was 10.53 kPa (1.22), whereas mean supine PaO<sub>2</sub> was 9.85 kPa (1.33). The difference between sitting and supine PaO<sub>2</sub> was 0.68 kPa (0.86) and was statistically significant. Sitting PaCO<sub>2</sub> was 5.06 kPa (0.47) and supine PaCO<sub>2</sub> was 5.05 kPa (0.54). The difference between sitting and supine PaO<sub>2</sub> correlated positively with FEV<sub>1</sub>/FVC %, negatively with the corresponding difference between sitting and supine PaCO<sub>2</sub>,<sub></sub>and negatively with BMI. <i>Conclusions:</i> We conclude that the significant difference in PaO<sub>2</sub> in sitting and supine positions clearly shows that the position needs to be considered both when attempting to establish reference values and when evaluating gas exchange in elderly persons. The positional changes in oxygenation are related to the corresponding change in PaCO<sub>2</sub>, and to FEV<sub>1</sub>/FVC % and BMI.
Airway Responsiveness to Inhaled Acetaldehyde in Subjects with Allergic Rhinitis: Relationship to Methacholine Responsiveness
Authors: Prieto L. , Sánchez-Toril F. , Gutiérrez V. , Marín M.J. 
Published: April 2003

<i>Background:</i> Asthmatic subjects have an exaggerated airway response to inhaled acetaldehyde, but no information is available on airway responsiveness to this bronchoconstrictor agent in subjects with allergic rhinitis. <i>Objective:</i> The aim of this study was to determine the effect of inhaled acetaldehyde on lung function in nonasthmatic subjects with allergic rhinitis. <i>Methods:</i> A total of 78 adults (43 subjects with allergic rhinitis, 16 asthmatics and 19 healthy subjects) were challenged with increased concentrations of acetaldehyde and methacholine. The response to each bronchoconstrictor agent was measured by the provocative concentration required to produce a 20% fall in FEV<sub>1</sub> (PC<sub>20</sub>). <i>Results:</i> The geometric mean PC<sub>20</sub> acetaldehyde value for asthmatics was 35.5 mg/ml compared with 67.6 mg/ml in subjects with allergic rhinitis and with 80.0 mg/ml in healthy subjects (p < 0.001). The PC<sub>20</sub> acetaldehyde values in the allergic rhinitis group were also significantly lower than in the healthy control group (p = 0.04). All of the subjects with allergic rhinitis and increased responsiveness to acetaldehyde showed airway hyperresponsiveness to methacholine, but 9 patients with hyperresponsiveness to methacholine failed to respond to acetaldehyde. <i>Conclusions:</i> We conclude that subjects with allergic rhinitis are less responsive to inhaled acetaldehyde than asthmatic subjects, but more than healthy controls. Furthermore, only approximately half the patients with allergic rhinitis and airway hyperresponsiveness to methacholine exhibit bronchoconstriction with inhaled acetaldehyde, thus suggesting that airway hyperresponsiveness to methacholine may not be the sole factor leading to bronchoconstriction in response to acetaldehyde.
The Flow-Cytometric Analysis of Nasopharyngeal Carcinoma Treated with Stereotactic Radiosurgery
Authors: Hu Zhengqing , Dong Renhe , Huang Kangmei , Dai Jiazhong , Pang Li 
Published: April 2003

Stereotactic radiosurgery has been used in the treatment of nasopharyngeal carcinoma. To analyze the effect of radiosurgery on the flow cytometry DNA index and progression of cells through the cycles, 4 recurrent nasopharyngeal carcinoma cases were treated with stereotactic radiosurgery. The distribution of cells through the cycles was measured by flow cytometry at various times thereafter. The 50% isodose curve was placed at the tumor margin and the margin dose was 20 Gy. Biopsy of the nasopharynx was performed before and 1, 3, and 6 months after treatment. The specimens were then subjected to flow-cytometric analysis. The percentage of cells in the S phase was 27.6 ± 1.0, 14.6 ± 0.8, 12.1 ± 1.6 and 11.3 ± 1.3%; the proliferating index was 39.1 ± 1.4, 17.0 ± 0.9, and 14.3 ± 1.2 and 14.1 ± 1.5%, and the DNA index was 1.5 ± 0.1, 1.6 ± 0.2, 1.7 ± 0.1 and 1.9 ± 0.1 before and 1, 3, and 6 months after treatment, respectively. It is suggested that the percentage of cells in the S phase and the proliferating index decreased to normal after treatment with stereotactic radiosurgery. This study explores the preliminary radiobiological effect of stereotactic radiosurgery on the DNA content and the distribution of cells through the cycles in nasopharyngeal carcinoma.
Miniature Multileaf Collimator as an Alternative to Traditional Circular Collimators for Stereotactic Radiosurgery and Stereotactic Radiotherapy
Authors: Urie Marcia M. , Lo Y.C. , Litofsky S. , FitzGerald T.J. 
Published: April 2003

<i>Purpose:</i> To evaluate the miniature multileaf collimator (MMLC) as an alternative to traditional circular collimators for radiosurgery. <i>Materials and Methods:</i> ‘Circular’ fields were created with the Radionics MMLC (leaf width 3.53 mm at isocenter). Beam data, including tissue maximum ratios, output factors, penumbrae and isodose distributions of these fields were measured. These were compared to the Radionics circular collimators traditionally used for radiosurgery. The MMLC data were input to the XKnife Treatment Planning System. Treatment plans were completed and evaluated using both the MMLC ‘circular’ fields and the circular collimators. <i>Results:</i> MMLC fields using 3, 5, 7, 9, 11, and 13 leaves on each side of the Radionics MMLC were created to approximate circular fields. The TMRs are essentially identical to those of comparable-size circular collimators. Measured at isocenter at 5-cm depth for 6 MV, the 80–20% penumbra widths are comparable to circular collimators, but are increased by as much as 1 mm at the leaf intersections (steps) where scalloping occurs. Isodose distributions were matched to those of circular collimators with comparable 50% isodose widths. Treatment plans for the MMLC ‘circular’ fields with four arcs (totaling 360<i>Conclusions:</i> With the MMLC simulating circular fields, dose distributions may be obtained which are essentially identical to comparable-size circular collimators. The mechanical accuracy of the MMLC is as good as that of the circular collimators, and the leakage dose is less. The diameter of ‘circular’ fields is limited by the MMLC leaf width to 1 cm and greater in increments of 7 mm. Attention needs to be paid to mechanical collisions because the MMLC is bulkier than the circular collimators.
Is Distortion Correction Necessary for Digital Subtraction Angiography in the Gamma Knife Treatment of Intra-Cranial Arteriovenous Malformations?
Authors: Perks J. , St. George E.J. , Doughty D. , Plowman P.N. 
Published: April 2003

<i>Objective:</i> The published literature maintains that distortion correction of digital subtraction angiography is essential for accurate definition of the arteriovenous malformation (AVM) nidus when performing Gamma Knife radiosurgery. However, as Gamma Knife treatments usually involve small volume targets, which are purposely positioned as close to the centre of the frame as possible, we postulated that the angiographic target images should be minimally distorted. Thus, the use of uncorrected images would not significantly compromise the accuracy of the treatment. We investigated this postulate.<i> Design:</i> Patient and phantom images with and without distortion correction were assessed. The errors measured in the angiograms were compared to those of MR and CT images of the same subjects. Any errors less than 0.5 mm in any modality were accepted as intrinsic. <i>Results:</i> All errors measured in the study were sub-millimetre. In the patient group, errors with distortion correction averaged 0.13 mm (range 0– 0.3 mm). Without distortion correction, errors averaged 0.34 mm (range 0.1–0.6 mm). By comparison, the average error for intracranial MR imaging was 0.3 mm, with a maximum of 0.6 mm. <i>Conclusion:</i> For small, intracranial AVMs distortion correction did not significantly reduce the errors associated with the definition of the stereotactic co-ordinates. We suggest that prior to the purchase of this software, similar in-house testing should be performed.
Cryoablation of Localized Prostate Cancer: Neoadjuvant Downsizing of Prostate Cancer with LH-RH Analogue Depot before Cryosurgery
Authors: Derakhshani P. , Zumbé J. , Neubauer S. , Engelmann U. 
Published: April 2003

Radical prostatovesiculectomy, radiation therapy, and complete androgen deprivation are acknowledged therapeutic concepts in the treatment of organ-confined prostate cancer. With cryoablation of the prostate, minimal invasive therapy has become available since 1991. Improvements in cryotechnique and progress in transrectal high-resolution ultrasound permit thermo-induced damage to the whole gland to be curative. Downstaging of prostate cancer by hormone ablative therapy remains a controversial issue at this time, but the use of androgen ablation decreases the size of the prostate gland which facilitates cryosurgery and improves the results. The freezing equipment has a limited capacity, and in certain instances large gland volumes prevent adequate freezing of the prostate. Since percutaneous prostate cryosurgery leaves dead tissue in situ to be resorbed over time, downsizing reduces the amount of necrotic tissue to be resorbed, reducing the potential for complications, particularly abscesses. The use of androgen ablation also increases the deposition of fat in the area of the Denonvillier’s fascia, making freezing of the rectum less likely during the procedure. In our study androgen ablative therapy was completed before performing cryosurgery in 26 of 43 patients (58%). The 17 patients not given androgen ablation therapy had gland volumes <40 ml, tumor volumes <3 ml, and no evidence of extracapsular tumor. The neoadjuvant therapy consisted of a 3- to 10-month course of leuprolide acetate combined with an antiandrogen.
The Incidence of Pharmacologically Induced Priapism in the Diagnostic and Therapeutic Management of 685 Men with Erectile Dysfunction
Authors: Perimenis P. , Athanasopoulos A. , Geramoutsos I. , Barbalias G. 
Published: April 2003

<i>Objective:</i> To evaluate the incidence of pharmacologically induced priapism in the diagnostic and therapeutic management of erectile dysfunction. <i>Patients and Methods:</i> Over a period of 7 years, 685 men were investigated for erectile failure. They underwent a simple test with vaso-active drugs, and the nonresponders were further investigated. Eventually, 83 men began autoinjections and 45 still continue. <i>Results:</i> Eight (1.2%) cases of priapism presented during the simple test with vaso-active drugs in these patients, while none occurred during self-injection treatment. Three were prolonged erections induced by prostaglandin E<sub>1</sub> (PGE<sub>1</sub>) and 5 by papaverine (Pap). Six were treated safely with intracavernosal injection of etilephrine without blood aspiration. <i>Conclusion:</i> Priapism is always a potential phenomenon where no individual, no particular drug and no specific dose are completely safe. It may be caused even with 5 µg of PGE<sub>1</sub> or 7.5 mg of Pap. Auto-injection therapy however is a safe kind of treatment in well-experienced patients. Careful regulation of the doses and practice in the use of vaso-active drugs may reduce the priapism rate.
Comparison of Ultrasound-Guided Biopsies and Prostatectomy Specimens: Predictive Accuracy of Gleason Score and Tumor Site
Authors: Gregori Andrea , Vieweg Johannes , Dahm Philip , Paulson David F. 
Published: April 2003

<i>Objective:</i> To critically evaluate the accuracy of sextant biopsies in predicting Gleason score and the site of tumor location in patients with clinically localized prostate cancer treated by radical perineal prostatectomy. <i>Methods:</i> The case records of 289 patients with clinically localized prostate cancer who underwent radical perineal prostatectomy were reviewed, comparing the Gleason score and tumor site location as determined by sextant ultrasound-guided core biopsies with the Gleason score and tumor distribution within the surgical specimens. The prostatectomy specimens were further characterized by extent of disease as organ-confined, specimen-confined or margin-positive. <i>Results:</i> The Gleason score was identical in 126 (43.5%) patients. An upgrading in the surgical specimen occurred in 118 (40.8%) cases, a downgrading in 43 (14.8%). Overall, 193 (66.7%) patients had a unilateral positive biopsy, while 96 (33.2%) patients had bilateral positive biopsies. Sixty-four (33.1%) patients with a unilateral positive biopsy had cancer confined to one side of the gland, while 127 (65.8%) showed bilateral disease; 142 (73.5%) patients had organ-confined tumors versus 51 (26.4%) patients with capsular penetration. In the 96 patients with bilateral positive biopsies, 64 (66.6%) patients had intracapsular cancer versus 32 (33.3%) patients with either specimen-confined or margin-positive disease. The overall rate of positive margins was 14%. Fifty-one (61.4%) of the 83 patients with non-organ-confined disease had posterolateral capsular penetration in the region of the superior pedicle of the neurovascular bundle, while 28 (33.7%) patients had apical capsular penetration, in the region of the inferior neurovascular pedicle. <i>Conclusions:</i> The ability of sextant ultrasound-guided biopsies to estimate the pathological grading is satisfactory: when we consider a difference of ± 1 in the final Gleason score, the overall correlation is 80%. In 66% of the cases, sextant biopsies predicted unilateral disease when bilateral disease existed. A unilateral positive biopsy does not predict unilateral disease.