bluuebunny/crossref_metadata_2025 huggingface dataset:
Development of Posterior Capsule Opacification in the Rabbit
Authors: Wallentin N. , Lundgren B. , Holmén J.B. , Lundberg C.
Published: April 2003

Purpose: The aim of the present study was to characterize the development of after-cataract in the rabbit by measuring its wet weight, protein, DNA and glycosaminoglycan (GAG) contents and using Scheimpflug and slitlamp analysis. Further, aqueous humor (AqH) leukocytes, protein and lens epithelial cell proliferation activity were determined. Methods: AqH was collected and capsular bags including after-cataract were dissected free on days 0, 1, 7, 14, 28 and 56 after cataract surgery. The wet weights were determined and the contents of DNA, protein and GAG in the capsular bags including after-cataract were analyzed. AqH was analyzed for leukocytes, protein and proliferative activity. In another set of experiments, rabbit eyes were analyzed by the Scheimpflug technique and slitlamp examination on days 0, 1, 7, 14, 28 and 56 after cataract surgery. The wet weight of the capsular bag with the after-cataract was also determined. Results: An increase was found in the wet weight (480%) and the contents of protein (221%), DNA (945%) and GAG (336%) of the capsular bags including after-cataract during the experimental period. In the AqH, all 3 variables measured, leukocytes, protein and proliferative activity, reached their highest levels on day 1 after surgery. In the second set of experiments, the wet weight of the capsular bag including after-cataract increased by 391% during the 56-day experimental period. Posterior capsule opacification (PCO), as measured by Scheimpflug analysis, increased from 0.8 to 81.7% and the scores of Elschnig’s pearls as well as fibrosis, analyzed by slitlamp, increased from 0.0 to 2.8 and 3.0, respectively. Conclusions: This study shows that the same components that are reported to be important in human PCO are also components of PCO in the rabbit. Thus, the rabbit model seems to accurately reflect human PCO development, and because PCO develops much faster in rabbits that would make the rabbit model suitable for studies to elucidate human PCO development.
Non-Paralleled Increase of Hepatocyte Growth Factor and Vascular Endothelial Growth Factor in the Eyes with Angiogenic and Nonangiogenic Fibroproliferation
Authors: Umeda Naoyasu , Ozaki Hiroaki , Hayashi Hideyuki , Kondo Hiroyuki , Uchida Hiroko , Oshima Kenji
Published: April 2003

Vascular endothelial growth factor (VEGF) has been known as principal angiogenic factor in vasculogenesis, tumor angiogenesis and ocular angiogenesis. Currently, hepatocyte growth factor (HGF) has been reported to play a major role in ocular angiogenesis. We studied distribution of both growth factors in angiogenic and non-angiogenic fibroproliferation to determine the correlation of VEGF and HGF in retinal angiogenesis. Concentrations of VEGF and HGF molecules in vitreous samples from 27 eyes with angiogenic proliferative diabetic retinopathy (PDR) and 9 eyes with non-angiogenic proliferative vitreoretinopathy (PVR) were measured by enzyme-linked immunosorbent assay (ELISA). Vitreous samples with idiopathic macular role (IMH) served as a control. Concentrations of VEGF in the angiogenic PDR were 4.3 ± 5.8 ng/ml (mean ± SD), and were significantly higher than in non-angiogenic PVR (0.5 ± 0.1 ng/ml). No significant differences were observed on VEGF concentrations between PVR to control. On the contrary, HGF concentrations were significantly higher in PVR (22.5 ± 21.8 ng/ml) than in control (6.9 ± 5.2 ng/ml), those of PDR (24.0 ± 16.3 ng/ml) were also significantly higher than control. Among PDR samples, VEGF concentration was significantly higher than in the subgroup with higher angiogenic activity represented by iris neovascularization, although there were no significant differences on HGF concentration between the subgroups. Focal increases in HGF on fibroproliferation in the eye regardless of the involvement of angiogenesis were not in remarkable relation with angiogenic activity, unlike VEGF. These data suggested a more extensive role of HGF than VEGF strictly related to angiogenesis.
Effect of Topical Betaxolol on the Acute Rise of Aqueous Flare Induced by Highly Selective Agonists for Prostaglandin E2 Receptor Subtypes in Pigmented Rabbits
Authors: Yanagisawa Shuichiro , Hayasaka Seiji , Zhang Xue-Yun , Hayasaka Yoriko , Nagaki Yasunori , Kitagawa Kiyotaka
Published: April 2003

Purpose: To evaluate the role of topical betaxolol on experimental ocular inflammation in rabbits. Method: Transcorneal diffusion of highly selective agonists for prostaglandin E2 receptor subtypes (EP), 25 µg/ml, with the use of a glass cylinder, was performed to produce aqueous flare elevation in pigmented rabbits. Betaxolol was topically administered before EP agonist application. Aqueous flare was measured with a laser flare cell meter. Results: Performing topical instillation of 0.5% betaxolol 4 times inhibited 52 ± 9% of EP2-agonist (ONO-AE1-259-01)-induced aqueous flare elevation. The inhibition of flare elevation was dependent on the number of betaxolol instillations. Betaxolol did not suppress the elevation induced by an EP4 agonist (ONO-AE1-392). Conclusion: Betaxolol inhibited EP2-agonist-induced aqueous flare elevation in pigmented rabbits.
Ocular Volume Change per Cardiac Cycle
Authors: Gee William , Reed III James F. , McDonald Kenneth M. , Madden Alice E.
Published: April 2003

Ocular pneumoplethysmograph (OPG) tests were performed in 499 employees of an industrial firm. The ocular volume change (OVC), in microliters per cardiac cycle, was calculated from each of OPG tests. In the 195 females, the OVC was 294 ± 81 µl. In the 304 males, the OVC was 269 ± 86 µl. The female-male OVC difference was significant, p = 0.001.
Melanotic Neuroectodermal Tumor of Infancy Discovered after Head Trauma
Authors: Paueksakon Paisit , Parker John R. , Fan X. , Miles Gordon , Ruiz Henry , Wushensky Curtis , Johnson Mahlon D.
Published: April 2003

Melanotic neuroectodermal tumor of infancy (MNTI) is a rare neoplasm that generally arises in the maxilla during the first year of life. Involvement of bones of the cranial vault or brain is extremely rare. We describe a 7-month-old black female who presented after falling out of bed onto a concrete floor. Subsequently, she developed an anterior frontal mass that enlarged over several days. Radiographs of the skull at her local hospital showed a depressed right frontal skull fracture. However, computerized tomography of the head (reviewed at our institution) revealed a slightly hyperdense extra-axial mass which crossed the anterior frontal midline, widening the metopic suture and extending into the anterior subgaleal scalp. Hyperostosis of the adjacent frontal calvarium was also present. A craniotomy revealed a dark, 1.5-cm calcified epidural lesion with some features of an unusual hematoma. Microscopic evaluation revealed a chronic hematoma and MNTI. The tumor recurred within a year. MNTI should be included in the differential diagnosis of epidural and skull lesions in infants.
Impact of Selective Posterior Rhizotomy on Fine Motor Skills
Authors: Mittal Sandeep , Farmer Jean-Pierre , Al-Atassi Borhan , Montpetit Kathleen , Gervais Nathalie , Poulin Chantal , Cantin Marie-André , Benaroch Thierry E.
Published: April 2003

Suprasegmental effects following selective posterior rhizotomy have been frequently reported. However, few studies have used validated functional outcome measures to report the surgical results beyond 3 years. The authors analyzed data obtained from the McGill Rhizotomy Database to determine the long-term impact of lumbosacral dorsal rhizotomy on fine motor skills. The study population comprised children with debilitating spasticity who underwent SPR and were evaluated by a multidisciplinary team preoperatively, at 6 months and 1 year postoperatively. Quantitative standardized assessments of upper extremity function were obtained using the fine motor skills section of the Peabody Developmental Motor Scales (PDMS) test. Of 70 patients who met the entry criteria for the study, 45 and 25 completed the 3- and 5-year assessments, respectively. Statistical analysis demonstrated significant improvements in grasping, hand use, eye-hand coordination, and manual dexterity at 1 year after SPR. More importantly, all improvements were maintained at 3 and 5 years following SPR. This study supports that significant improvements in upper extremity fine motor function using the PDMS evaluative measure are present after SPR and that these suprasegmental benefits are durable.
Schwannoma of the Tentorium Cerebelli in a Child
Authors: Jabbour Pascal , Rizk Tony , Lahoud Georges Abi , Hourani Roula , Checrallah Antoine , Samaha Elie , Nohra Georges , Moussa Ronald , Okais Nabil
Published: April 2003

Intracranial schwannomas not arising from a cranial nerve are very rare. Schwannomas of the dura are even rarer; in the literature, we found only two cases: a schwannoma of the falx and one of the torcula. We report a third case of a 9-year-old girl with a schwannoma of the tentorium cerebelli. The different theories concerning the origin of this tumor in this particular location are discussed.
Clinical Application of Neuroendoscopic Techniques
Authors: Zhang Yazhuo , Wang Chungcheng , Liu Peinan , Gao Xianhong
Published: April 2003

We treated 126 patients with different neurosurgical diseases by performing endoscopic neurosurgery, endoscopy-controlled microneurosurgery and endoscopy-assisted microneurosurgery. The indications were intracranial cysts in 51 patients, brain cysticercosis in 10 patients, hydrocephalus in 31 patients, and epidermoid cysts in 34 patients. The follow-up period ranged from 6 to 24 months (mean follow-up duration 9 months). After operation, 115 of 126 patients had improvement in their initial symptoms, 7 had no change and 4 developed complications, including subarachnoid hemorrhage (SAH), intraventricular hemorrhage, and transient cardiopulmonary dysfunction. It is concluded that (1) neuroendoscopic techniques show a distinct value in the treatment of deep-seated, intracranial diseases, or ventricle and cistern lesions; (2) neuroendoscopic techniques play an important role in microneurosurgery and consequently improve surgical quality; (3) the benefits of neuroendoscopic techniques include less surgical manipulation and trauma, milder postoperative reaction, decreased expenses and shortened hospitalizations.
Abdominal Sacral Colpopexy with Mersilene Mesh
Authors: Leonardo C. , Gentili G. , Leonardo F.
Published: April 2003

Introduction: This study focussed on abdominal sacral colpopexy with Mersilene mesh to correct total vaginal vault prolapse. Our aim was to describe and explain our operative modifications. Materials and Methods: From 1992 and 1999, we performed sacrocolpopexy on 25 patients for vaginal vault prolapse. We proposed a change by interposing a mesh between the vaginal vault and the sacral promontory shaped as an inverted ‘V’. Results: No intraoperative or postoperative complications were encountered; to date the outcome of all patients was satisfactory. Conclusion: Based on the results of the follow-up, this new surgical approach of abdominal sacral colpopexy can be considered as effective surgery for vaginal vault prolapse.
Early Catheter Removal following Transurethral Prostatectomy:Overnight Catheterization
Authors: Aslan Güven , Çelebi İlhan , Arslan Deniz , Esen A. Adil
Published: April 2003

Objective: Our aim was to determine the safety and feasibility of catheter removal on the first morning after transurethral prostatectomy. Methods: Fifty-four patients who underwent transurethral prostatectomy were included in a prospective study. The decision to remove the catheters on the first morning after surgery was based on the color of the catheter effluent, absence of clots, normal vital signs and adequate urine output. Patients who voided successfully were discharged on the same day as catheter removal. Results: Catheters were removed in 43 (79.6%) patients on postoperative day 1. Of these patients 40 (93%) voided successfully, however 3 of them required recatheterization due to bleeding or urinary retention. The criteria for catheter removal were not met in 11 patients and their catheters were removed on postoperative day 2 in 2 and on postoperative day 3 in 9. The mean length of hospital stay after surgery was 1.74 days for the entire group and 1.41 days for those in whom the catheter was removed on postoperative day 1. Conclusion: Overnight catheterization after transurethral prostatectomy seems to be a feasible approach without leading to significant morbidity in selected patients.
Thymidine Phosphorylase and Dihydropyrimidine Dehydrogenase in Bladder Cancer
Authors: Iizumi Tatsuo , Hariu Kyouichi , Sato Mika , Sato Satoshi , Shimizu Hirofumi , Tomomasa Hiroshi , Umeda Takashi
Published: April 2003

Thymidine phosphorylase (TP) and dihydropyrimidine dehydrogenase (DPD) levels in transitional cell carcinoma of the bladder resected from 38 patients were examined by ELISA. TP levels in high-grade and invasive cancer were significantly higher than those in low-grade and superficial cancer, respectively. No significant differences in the DPD levels were observed among grades and stages, but the DPD/TP ratio was significantly lower in grade 3 tumor than in grade 1. These results demonstrated that 5′-deoxy-5-fluorouridine seemed to be useful for managing patients with grade 3 cancer. The present study also suggested that we might be able to exclude cases of bladder cancer in which 5-fluorouracil group medicines would be inappropriate candidates in treatment options by measuring both TP and DPD levels in the tumor.
The Challenge of Invasive Fungal Infection
Authors: de Pauw B.E. , Meunier F.
Published: April 2003

Systemic fungal infections cause almost 25% of the infection-related deaths in leukaemic patients. Particularly those with prolonged neutropenia are at risk but mycoses also feature in critically ill intensive care patients and in individuals who are treated for solid tumours and AIDS, or who received an organ transplant. The spread of AIDS and the more aggressive cytotoxic chemotherapy in combination with an improved management of haemorrhages and bacterial infections in leukaemic and other cancer patients facilitated the occurrence of these invasive fungal infections. These life-threatening complications remain both difficult to diagnose and to treat and therefore carry a poor prognosis. For many years, the only realistic option to treat systemic infections was amphotericin B, whose administration was known to be associated with numerous adverse effects. Now less toxic formulations of amphotericin have become available for clinical use, as well as several new triazoles that appear to provide an effective and less toxic alternative for the treatment of certain fungal infections.
Clinical Efficacy of Amphotericin B Colloidal Dispersion against Infections Caused by Candida spp
Authors: Dupont B.
Published: April 2003

Five clinical trials of the efficacy of amphotericin B colloidal dispersion (ABCD) primarily in patients unable to tolerate or failing treatment with conventional amphotericin B (CAB) were reviewed. A total of 572 patients were treated. Systemic candidal infections were identified in 107 evaluable patients and 239 in the intent-to-treat population. Seventy percent of the evaluable patients and 50% of the intent-to-treat patients achieved a complete or partial response. There were no significant differences either in response rates for different underlying causes or in response rates according to enrolment reason. The efficacy of ABCD at doses of 3–4 mg/kg/ day in disseminated candidiasis appears to be similar to that in studies using CAB. Renal and hepatic toxicity of ABCD is low.
Treatment and Implications of Multidrug-Resistant Tuberculosis for the 21st Century
Authors: Iseman Michael D.
Published: April 2003

Drug-resistant tuberculosis fundamentally reflects inadequate chemotherapy. To prevent increases in the prevalence of resistance, physician education and more structured treatment programs are needed. In one recent series, 80% of patients with multidrug-resistant tuberculosis (MDR-TB) had been previously managed with clear breaches of standard practice. These errors included adding a single drug to a failing regimen, failing to identify initial or acquired resistance, using an inadequate regimen, and not recognizing (and coping with) non-adherence to therapy. Both medical and surgical management should be considered in optimizing treatment of patients with MDR-TB. Optimal treatment strategies for MDR-TB are outlined in this paper. The use of susceptibility testing is strongly advised, but in situations where such laboratory services are not available, empirical management regimens are discussed.
Increasing Prevalence of High-Level Gentamicin Resistance among Enterococci Isolated in Greece
Authors: Tsakris A. , Pournaras S. , Maniatis A.N. , Douboyas J. , Antoniadis A.
Published: April 2003

High-level gentamicin-resistant enterococci (HLGRE) (MIC >512 µg/ml) were frequently recovered in the AHEPA University Hospital, Thessaloniki, Greece, during a 15-month period (67/158, 42.4%). PCR testing showed that high-level gentamicin resistance was attributable to the presence of the aac(6′)-aph(2′′) gene, while the recently described genes aph (2′′)-Ic and aph(2′′)-Id were not detected. High-level gentamicin resistance could be transferred with varying frequency from 41 of 57 Enterococcus faecalis and 5 of 10 Enterococcus faecium isolates. All transconjugants acquired high-level resistance to streptomycin. HLGRE cause therapeutic problems in our region, since none of the clinically available aminoglycosides can be used in severe infections.
Patterns of Antibiotic Resistance, Serotype Distribution, and Patient Demographics of Streptococcus pneumoniae in Hong Kong
Authors: Ip M. , Lyon D.J. , Cheng A.F.B.
Published: April 2003

Streptococcus pneumoniae isolates from clinical specimens during the period 1993–1997 at the Prince of Wales Hospital, Hong Kong, were analysed by the antibiotic resistance profiles, the distribution of serotypes, specimen types, and patient demographics. 1,229 non-duplicate S. pneumoniae isolates were evaluated; 84% from the respiratory tract, 11% from blood and cerebrospinal fluid and the remainder from body fluids and pus swabs. The percentage of S. pneumoniae of reduced penicillin susceptibility was 38.6%, and the percentage resistance to erythromycin, chloramphenicol, co-trimoxazole and tetracycline were 40.4, 43.2, 54.9 and 77.8%, respectively. The organism was isolated from patients of all age groups, 14.6% from children aged below 10 years, half of whom were from children aged 2 years or below. 57.0% were from elderly patients aged above 60. The male to female ratio was 2.5:1. Isolates with reduced penicillin susceptibility were seen significantly more so in children under 10 than in those aged 11 or above (52 versus 36%, p < 0.0001). A diverse range of serotypes was obtained in the penicillin-susceptible isolates whilst those of reduced susceptibility were confined to serotypes 23F, 19F, 6B, 14 and 9V.
In vitro Activity and Post-Antibiotic Effect of Quinupristin/Dalfopristin (Synercid)
Authors: Ling Thomas K.W. , Fung Kitty S.C. , Cheng Augustine F.B.
Published: April 2003

The in vitro activities of quinupristin/dalfopristin (Synercid), ampicillin, erythromycin, clarithromycin, vancomycin, teicoplanin, ciprofloxacin and tetracycline were examined and compared against 526 gram-positive bacteria. The minimal inhibitory concentrations (MICs) for quinupristin/dalfopristin against Staphylococcus aureus, including methicillin-resistant strains, were low (MIC90 = 0.5 mg/l), and were comparable with those of vancomycin and teicoplanin. This compound was superior to the macrolides and highly active against Streptococcus pneumoniae (both penicillin-sensitive and penicillin-resistant strains), with MIC90 = 2 mg/l. It was also active against other streptococci, with MIC90 = 4 mg/l. However, this agent is less active against enterococci (MIC90 = 32 mg/l). Quinupristin/dalfopristin showed high activity against gram-positive anaerobes, including Clostridium spp., Peptococcus spp. and Peptostreptococcus spp., with MIC90 ≤2 mg/l. Quinupristin/dalfopristin was also investigated for its post-antibiotic effect (PAE) and bactericidal kinetics against nine strains of gram-positive organisms, including staphylococci, enterococci and pneumococci. Exponentially growing (log phase) cultures were exposed to quinupristin/dalfopristin at 2 × MIC. Growth kinetics was evaluated using viable counting. The drug was uniformly bactericidal against pneumococci and staphylococci within 2 and 8 h of exposure, respectively. The killing activity against enterococci was weak; there was little or no reduction in bacterial count over 24 h of incubation. PAEs ranging from 2.13 to 3.28 h, 0.92 to 3.02 h and 1.89 to 7.07 h were produced on the tested pneumococci, staphylococci and enterococci, respectively. This study showed that quinupristin/dalfopristin is a promising agent active against gram-positive bacteria. The prolonged PAEs also suggest that the drug could be used intermittently at more widely spaced dosing intervals against gram-positive organisms.
Evaluation of Spontaneous Contamination of Ocular Medications
Authors: Marchese A. , Bozzolasco M. , Gualco L. , Schito G.C. , Debbia E.A.
Published: April 2003

Background: In order to evaluate whether single-dose ophthalmic preparations in 0.5-ml containers can safely be used within 24 h after the first opening, eigth different sterile ocular medications containing timolol, jaluronic acid, diclofenac, ketotifen, pilocarpine, formocortal, formocortal-gentamycin, and tetryzoline-feniramine (Farmigea, Italy) were opened and tested for spontaneous bacterial contamination after exposure to air. Methods: Samples (10 µl) were collected from exposed ophthalmic preparations after 0, 2, 4, 8 and 24 h. Results: No viable microorganisms were detected during and at the end of the evaluation period. In order to assess whether the resident or pathogenic ocular bacterial population due to repeated handling might contaminate the medications, about 105 cells of different species (Staphylococcus aureus, coagulase-negative staphylococci, Streptococcus pneumoniae, Streptococcus spp., Corynebacterium spp., Pseudomonas aeruginosa, Neisseria spp., Acinetobacter spp., Haemophilus influenzae, Escherichia coli and Candida albicans) were added to the containers and incubated at 37°C or at room temperature. Samples were collected and the number of viable bacteria was estimated. The antibacterial effect of the ophthalmic compounds varied depending on the species considered. Tetryzoline-feniramine, pilocarpine, ketotifen and formocortal-gentamycin exhibited a frank bactericidal activity (<100 survivors after 18–24 h of exposure) against the great majority of the species tested. Conclusion: These results indicate that the risk of spontaneous contamination of ophthalmic preparations after their first opening is low, and that all preparations tested exhibit an aspecific antibacterial activity. As a consequence, the safe usage of these ocular medications could be extended from the recommended 3 h to at least 24 h after the first usage.
Effects of Antibiotics on Adherence of Pseudomonas aeruginosa and Pseudomonas fluorescens to Human Fibronectin
Authors: Di Martino Patrick
Published: April 2003

The effect of subminimal inhibitory concentration (½ MIC) of antimicrobial agents on the adherence of fluorescent Pseudomonas to human fibronectin (FN) was investigated by examining two Pseudomonas fluorescens and four Pseudomonas aeruginosa strains. The Escherichia coli (MC1061 and JM109) strains, used as negative controls, adhered poorly to FN immobilized on microtiter wells (adherence indices of 0.04 ± 0.02 and 0.03 ± 0.01 105 CFU/well, respectively). Two P. aeruginosa strains (NK125502 and ER82483) were highly adherent to FN (adherence indices of 3.22 ± 0.75 105 and 3.08 ± 1.42 105 CFU/well, respectively), the two others (ER98513 and ER92581) adhered less efficiently (adherence indices of 0.91 ± 0.05 105 and 0.45 ± 0.23 105 CFU/well, respectively). The two P. fluorescens strains (MF0 and ER74508) were highly adherent to fibronectin (adherence indices of 7.06 ± 1.00 105 and 2.08 ± 0.67 105 CFU/well, respectively). Cefsulodin was the only antimicrobial agent tested that decreased the FN adherence of the majority of the strains: decrease in adherence highly significant (p < 0.01) for the P. fluorescens MF0 strain, significant (p < 0.05) for the P. aeruginosa NK125502, ER98513 and the P. fluorescens ER74508 strains, and not significant for the P. aeruginosa ER92581 strain. The effects of chloramphenicol and polymyxin B on the adherence of Pseudomonas were strain dependent. Gentamicin had no statistically significant effect on bacterial adherence. We conclude that, in addition to its antibacterial activity, cefsulodin could be effective in preventing the adherence of fluorescent Pseudomonas to FN, an important property in the presence of injured epithelium and coated biomaterials.
Management of Endocarditis: Outpatient Parenteral Antibiotic Treatment in Argentina
Authors: Lopardo Gustavo
Published: April 2003

Patients with infective endocarditis often face lengthy hospitalization for parenteral antibiotic therapy. Efforts to reduce medical costs have led to consideration of outpatient parenteral antibiotic treatment (OPAT) for these patients. However, concerns about outpatient management of complications, particularly congestive heart failure and emboli, exist. In Argentina, carefully selected patients with infective endocarditis, representing a low-risk population, have been successfully treated with OPAT. A retrospective analysis was conducted of 48 such patients. Three delivery models were used: at home with medications given by the visiting nurse, at infusion center, or at home with medications self-administered [1, 2]. Ten patients received OPAT only; 38 were initially hospitalized, then transferred to an OPAT program. Twenty-nine patients had streptococcal disease, 37 out of 48 patients were treated with ceftriaxone. Clinical and microbiologic cure was achieved in all patients. Three patients developed heart failure, 2 prior to starting antibiotic therapy. Four developed emboli, all prior to starting antibiotics. Surgery was required in 5 patients: 2 were treated with OPAT postoperatively and 3 had surgery after antibiotic therapy was completed. OPAT for infective endocarditis is safe in well selected patients
Evaluation of the New VITEK 2 System for Determination of the Susceptibility of Clinical Isolates of Streptococcus pneumoniae
Authors: Chávez Mónica , García López Jose Luis , Coronilla Julian , Valverde Anastasio , Serrano M. Carmen , Claro Rosa , Martín Mazuelos Estrella
Published: April 2003

Background: The VITEK® 2 is a new version of the automated system for organism identification and susceptibility testing. One of the differences between this system and its predecessor, VITEK, is the ability to perform rapid susceptibility testing of Streptococcus pneumoniae. This study compares the results of susceptibility testing of S. pneumoniae using the VITEK 2 system and a commercial microbroth dilution method, Sensititre. Methods: A group of 214 clinical isolates of S. pneumoniae were selected to include isolates with previously documented penicillin resistance. The antimicrobial agents tested were benzylpenicillin, cefotaxime, erythromycin, trimethoprim/sulfamethoxazole, tetracycline, chloramphenicol, imipenem and vancomycin. Results: The best agreement was achieved with vancomycin (100%), erythromycin (95.8%) and tetracycline (95.8%). The lowest level of agreement was found with benzylpenicillin (88.6%) and cefotaxime (90.1%). We observed rates of 12.3 and 15.7% for minor errors with penicillin and cefotaxime, respectively, and 1 very major error for cefotaxime. Conclusion: The VITEK 2 allows rapid determination of the antimicrobial susceptibility of S. pneumoniae and demonstrated a good degree of agreement with the Sensititre method for most of the antimicrobials tested.
Cytotoxic Effects of Diazenes on Tumor Cells in vitro
Authors: Moskatelo Dubravka , Benjak Aleksandar , Laketa Vibor , Polanc Slovenko , Košmrlj Janez , Osmak Maja
Published: April 2003

Background: We have shown previously that diazenecarboxamides (diazenes) were cytotoxic for several tumor cell lines. Their target seems to be the intracellular glutathione (GSH). To improve the solubility and biological activity of these drugs, new compounds have been synthesized. In the present study we examined the cytotoxic effect of six new diazenes: BR-25, UP-39, UP-11, JK-1024, RL-514 and RL-625. Methods: The cytotoxicity of diazenes was tested on nine human tumor cell lines: laryngeal carcinoma HEp2 cells, cervical carcinoma HeLa cells, mammary carcinoma MCF-7 cells, breast adenocarcinoma SK-BR-3 cells, and glioblastoma A1235 cells and their four drug-resistant cell lines. Cytotoxicity was determined using the colorimetric MTT assay. The intracellular GSH content (following the treatment with diazenes) was examined spectrophotometrically in human cervical carcinoma cells by the procedure developed by Tietze. Results: Results show that diazene UP-39 was mostly efficient, significantly reducing the cell survival of all nine cell lines examined, including four drug-resistant cell lines. Diazenes UP-11, RL-514 and BR-25 given in the highest concentrations decreased the survival of some examined cell lines, but to less than 50%. Diazenes RL-625 and JK-1024 had no influence on the cell survival. None of the examined diazenes significantly influenced the intracellular level of GSH. Conclusion: Our results suggest that diazene UP-39 may be a promising new drug for the treatment of tumors and encourage further research on this compound.
Analysis of CCR5Δ32 Geographic Distribution and Its Correlation with Some Climatic and Geographic Factors
Authors: Limborska Svetlana A. , Balanovsky Oleg P. , Balanovskaya Elena V. , Slominsky Peter A. , Schadrina Maria I. , Livshits Ludmila A. , Kravchenko Sergey A. , Pampuha Vladimir M. , Khusnutdinova Elza K. , Spitsyn Victor A.
Published: April 2003

We studied the possible effects of climatic-geographic factors on the world distribution of the mutant allele for the chemokine receptor gene CCR5, which has a 32-bp deletion (CCR5Δ32) preventing cell invasion by the primary transmitting strain of HIV-1. New data on CCR5 polymorphisms in Russian, Ukrainian, and Moldavian populations are presented. All available data on CCR5Δ32 frequencies in the Old World (number of populations n = 77) were used for construction of a geographical gene map to analyze possible correlations between allele frequencies and eight climatic-geographic parameters. A strong positive correlation was found between the allele frequency and latitude (r = 0.72), a strong negative correlation with annual radiation balance (r = –0.66), and a weaker negative correlation with longitude (r = –0.34). Partial correlations were calculated excluding the influence of latitude. The negative correlation between the allele frequency and annual radiation balance decreased (r = –0.42), but remained large and significant. We propose that the existence of correlations between the cline of CCR5Δ32 frequencies and climatic-geographic parameters provides evidence for a possible effect of either natural environmental factors or large-scale population movements on the distribution of this allele.
Stroke Case Fatality in Denmark from 1977 to 1992: The Copenhagen City Heart Study
Authors: Truelsen Thomas , Grønbæk Morten , Schnohr Peter , Boysen Gudrun
Published: April 2003

Background and Purpose: Stroke mortality rates have decreased in Denmark but little is known about the reasons for these changes. One possible explanation is decreased case-fatality, and the aim of the present investigation was to study trends in case-fatality for first-ever stroke in a large population-based cohort study in Copenhagen, Denmark. Subjects and Methods: The Copenhagen City Heart Study comprised 19,698 inhabitants in Copenhagen, Denmark. Linkage to two national registers enabled identification of all subjects irrespective of participation in the study examinations. Follow-up in the present study was from January 1, 1977 to December 31, 1992. Case fatality after 7 days, 28 days, 1 year and 1 year in 28-day survivors was assessed for first-ever stroke. Uniform identification and validation methods made it possible to estimate trends in case-fatality. The World Health Organization’s definition of stroke was used, and stroke was categorized into either unspecified stroke, ischemic infarction, intracerebral hemorrhage, or subarachnoid hemorrhage. The effect of time was estimated by means of multiple logistic regression analyses adjusting for gender, age at onset and type of stroke. Results: A total of 1,213 strokes occurred during the study period from 1977 to 1992 in the study population. The case-fatality was highest during the first 28 days, and especially the initial 7 days; thereafter a steady state was reached. From the period 1977–1980 to the period 1989–1992 case-fatality did not change in analyses of 7-day case-fatality odds ratio (OR) = 1.14 (95% confidence interval, CI: 0.98–1.33), or of 28-day case-fatality OR = 1.06 (95% CI: 0.92–1.20), or of 1-year case-fatality OR = 0.95 (95% CI: 0.84–1.07). In the 1-year case-fatality, including only 28-day survivors, a significant decrease was found OR = 0.81 (95% CI: 0.67–0.97). Men had a significantly lower 7-day case-fatality than women; OR = 0.73 (95% CI: 0.52–0.99), but the difference attenuated in subsequent analyses and did not remain statistically significant. Conclusion: During the period 1977–1992, the 1-year case-fatality decreased in stroke patients who survived the initial 28 days, whereas no changes were observed in 7-day, 28-day and 1-year case-fatality.
Negligible Effects of Depression on Verbal and Spatial Performance in Alzheimer’s Disease
Authors: Berger Anna-Karin , Fahlander Kjell , Wahlin Åke , Bäckman Lars
Published: April 2003

We examined whether a diagnosis of depression affects verbal and visuospatial performance in Alzheimer’s disease (AD). Using data from a population-based study, persons with AD and depression (AD/D), AD alone and a control group of normal older adults were compared in two tests of verbal ability (category and letter fluency) and two tests of visuospatial skill (block design and clock drawing). As expected, there were clear AD-related deficits across all cognitive tasks. More importantly, the AD and AD/D groups were indistinguishable on all task variables. The lack of effects of depression was discussed relative to the view that those symptoms of this disease which are especially detrimental to cognitive functioning (e.g. concentration difficulties, lack of interest, loss of energy) may already be present in AD as a result of the neurodegenerative process.
Activation of 5-HT Receptors That Stimulate the Adenylyl Cyclase Pathway Positively Regulates IGF-I in Cultured Craniofacial Mesenchymal Cells
Authors: Lambert H. Wayne , Weiss Ellen R. , Lauder Jean M.
Published: April 2003

Results of the present study demonstrate that activation of the adenylyl cyclase/protein kinase A (PKA) pathway leads to increased levels of insulin-like growth factor I (IGF-I) in cultured embryonic mouse mandibular mesenchymal cells. Treatment of serum-free cultures with 10–8M 8-OH-DPAT (DPAT) or with 10–5M forskolin in the presence of the phosphodiesterase inhibitor isobutylmethylxanthine (IBMX; 10–5M) increased levels of IGF-I (but not IGF-II), as measured by [125I]protein A immunobinding. In a previous study, we showed that DPAT, forskolin, IBMX and the 5-HT4 receptor agonist SC53116 all increased the synthesis of cyclic adenosine monophosphate (cAMP) in these cultures. Taken together, these results provide evidence that stimulation of the adenylyl cyclase/PKA pathway in embryonic mandibular mesenchymal cells positively regulates IGF-I. This is supported by the ability of the PKA inhibitor Rp-cAMPS to block increases in IGF-I caused by both DPAT and forskolin. Consistent with these results, DPAT and forskolin increased phosphorylation of the cAMP response element binding protein (CREB), which was also blocked by Rp-cAMPS. These results suggest that activation of 5-HT receptors positively coupled to the adenylyl cyclase/PKA pathway may promote transcription of IGF-I through a cAMP response element (CRE) in the IGF-I promoter. This may represent one mechanism whereby 5-HT positively regulates IGF-I expression in developing craniofacial mesenchymal cells.
Survival Effects of Pigment Epithelium-Derived Factor Expressed by a Lentiviral Vector in Rat Cerebellar Granule Cells
Authors: Nomura Takuo , Yabe Takeshi , Mochizuki Hideki , Reiser Jakob , Becerra S.P. , Schwartz Joan P.
Published: April 2003

We have previously shown that pigment epithelium-derived factor (PEDF) acts as a survival factor for cerebellar granule cells (CGCs), by blocking apoptotic death, and can also protect these cells against glutamate-induced neurotoxicity. In preparation for gene therapy studies, pseudotyped HIV-1-based lentiviral vectors containing the PEDF gene, as well as either green fluorescent protein or β-galactosidase, were prepared. These bicistronic vectors are unique in that they express two genes efficiently under one promoter. Primary cell cultures of CGCs from postnatal day 8 rats were infected with the vectors encoding PEDF. RT-PCR demonstrated expression of mRNA and Western blot analysis confirmed that infected CGCs secrete PEDF protein to the medium. Assays for cell survival demonstrated that PEDF-infected cells were significantly more protected compared with mock-infected controls for 6–8 days in culture, as well as against induced apoptosis. The PEDF vectors expressing tat (trans-acting transcription factor) provided more protection than the tat(–) vectors. These results demonstrate that while the lentiviral vectors expressing PEDF are as neuroprotective as the protein itself for CGCs, the vectors have the advantage of providing long-lasting expression of PEDF protein, which will be more effective in in vivo studies. The present results suggest that this system may be useful for gene therapy for neurodegenerative disorders.
Chemokine GRO1 and the Spatial and Temporal Regulation of Oligodendrocyte Precursor Proliferation
Authors: Robinson Shenandoah , Franic Linda A.
Published: April 2003

Oligodendrocyte precursor proliferation is precisely regulated spatially and temporally during development to allow optimal myelination of the central nervous system (CNS). We propose that a paracrine regulatory pathway involving the chemokine GRO1 and platelet-derived growth factor (PDGF) permit local control of precursor proliferation in the brain. GRO1, PDGF, and their receptors act synergistically to precisely regulate oligodendrocyte precursor proliferation in vitro and in vivo in the rat CNS. The nature of the paracrine regulatory loop with astrocyte and neuronal GRO1 expression in a pattern that is closely correlated with PDGFαR+ oligodendrocyte precursors suggests that the GRO1/PDGF regulatory mechanism provides local control of oligodendrocyte precursor proliferation during development.
The Contribution of High-Frequency Stimulation in Vestibular Testing
Authors: Elidan Josef , Rodionov Vladimir
Published: April 2003

Recently it was shown that abrupt head acceleration impulses induce short latency response in the neuronal pathways of the vestibular system and a short latency vestibulooculomotor response. This phenomenon cannot be explained only with the frame of the classical torsion pendulum model of the cupuloendolymphatic system and passive reaction of the vestibular receptors to the cupular displacement. All three stages of stimulus transduction: mechanical, receptive and neuronal, are revisited in recent studies, and these findings are analyzed in the present paper. The head impulse test of Halmagyi and his colleagues, the high frequency head oscillations using special helmet [Tabak et al., 1995, 1997a, b], the autorotation test [O’Leary, 1990; Hirvonen 1998], the technique of recording vestibular evoked potentials to acceleration impulses [Elidan at al.] are discussed. In spite of some deficits in our knowledge, the exclusive diagnostic value of the high-frequency and high-intensity (impulse) stimuli became already obvious. It is concluded that the proper differentiation between the mechanical, receptor and afferent neuronal parts of the vestibular end organ may be achieved only by applying stimuli with different frequency content. Further investigations are requested to elucidate the specific mechanisms of vestibular sensitivity to the different stimuli used for this purpose, and the possible directions of these studies are discussed.
What Is Useful in Vestibular Testing?
Authors: Wiener-Vacher Sylvette
Published: April 2003

This review compares the efficiency of currently available test for diagnosing patients suffering vertigo based upon our experience since 1991 in the ORL Department of the Robert Debré Pediatric Hospital in Paris. A battery of instrument-based tests were adapted for children including testing the canal system (caloric bithermal test, earth vertical axis rotation and pendular rotation), testing the otolith system (off-vertical axis rotation, subjective vertical and horizontal measurement, vestibular myogenic potentials). This battery of tests was always preceded by a complete neurovestibular examination which included many tests that attempt to reproduce the same vestibular stimulation as the instrument-based tests. The usefulness of the respective instrument-based tests depends upon the investigative priorities determined by the characteristics of each case: beside the priority for determining the etiology of the vertigo, it can also be essential to date the onset of the inner ear disease, to evaluate the degree of fluctuation of vestibular function, to assess of completeness of a vestibular lesion, or establish a report of lesions for insurance or legal purposes. For 80–85% of cases of equilibrium problems in children, the minimum testing required for diagnosis is confined to a complete clinical vestibular and neurological examination as well as a caloric test. The more specialized tests become necessary for evaluations of variability or progressiveness of a vestibular impairment, comparisons of results between successive examinations, and assessment of the completeness of a vestibular lesion.
Comparative FISH mapping of Gab1 and Gab2 genes in human, mouse and rat
Authors: Yamada K. , Nishida K. , Hibi M. , Hirano T. , Matsuda Y.
Published: April 2003

Gab1 and Gab2 are members of the Gab family which act as adapters for transmitting various signals in response to stimuli through cytokine and growth factor receptors, and T- and B-cell antigen receptors. We determined chromosome locations of the two genes in human, mouse and rat by fluorescence in situ hybridization. The Gab1 gene was localized to chromosome 4q31.1 in human, 8C3 in mouse and 19q11.1→ q11.2 in rat, and the Gab2 gene was located on chromosome 11q13.4→q13.5 in human, 7E2 in mouse and 1q33.2→q33.3 in rat. All human, mouse and rat Gab1 and Gab2 genes were localized to chromosome regions where conserved homology has been identified among the three species.
A gene on pig chromosome 14 suppresses cellular anchorage independence of the mouse cell line GM05267
Authors: Gao X. , Islam M.Q.
Published: April 2003

We have generated pig–mouse somatic cell hybrids by fusing normal pig fibroblasts with an anchorage independent mouse cell line GM05267. High quality G-banding analysis was applied to a set of 18 hybrid cell lines derived from 15 independent hybrids and chromosomes were identified. Cytogenetic analysis showed that all hybrids contained one or several pig chromosomes with normal morphology devoid of any structural changes. Out of 18 hybrids tested for colony formation in soft agar, 15 were suppressed for anchorage independence while the remaining three were not suppressed. Correlation of the cellular phenotype with the pig chromosome content of the hybrids suggests that the suppressor function for anchorage independence is located on pig chromosome (SSC) 14. We have previously shown that a suppressor gene for anchorage independence (SAI1) is located on rat chromosome (RNO) 5 and another suppressor gene for the same phenotype is located on human chromosome (HSA) 9. Given the genetic homology of both RNO5 and HSA9 with two pig chromosomes including SSC14, the third suppressor gene we have mapped on SSC14 may well be a functional homologue of the previously identified rat and human genes.
Cytogenetic characterization of the TM4 mouse Sertoli cell line. I. Conventional banding techniques, FISH and SKY
Authors: Guttenbach M. , Steinlein C. , Engel W. , Schmid M.
Published: April 2003

Permanent Sertoli cell lines provide an ideal system for the in vitro analysis of function and responsiveness to biochemical/hormonal factors of this particular cell type. In general, cytogenetic analyses of cell lines often reveal remarkable chromosomal changes that may be associated with functional characteristics. In the present study we investigated the mouse Sertoli cell line TM4 by C-banding, silver staining, FISH and spectral karyotyping (SKY). A highly increased chromosome number (average 85–95) as well as five stable marker chromosomes were detected by the conventional staining techniques. SKY identified the markers as a translocation chromosome T(1;3), isochromosomes 11 and 18 and two different-sized microchromosomes. The results show the usefulness of combining SKY and conventional banding methods for the evaluation of chromosome alterations in widely used cell lines.
The pericentromeric region of human chromosome 11: evidence for a chromosome-specific duplication
Authors: Zhang J. , Qin S. , Sait S.N.J. , Haley L.L. , Henry W.M. , Higgins M.J. , Nowak N.J. , Shows T.B. , Gerhard D.S.
Published: April 2003

We have identified a chromosome duplication in the pericentromeric region of human chromosome 11 located in 11p11 and 11q14. A detailed physical map of each duplicated region was generated to describe the nature of the duplication, the involvement at the centromere and to resolve the correct maps. All clones were evaluated to ensure they were representative of their genetic origin. The order of clones, based on their marker content, as well as the distance covered was determined by SEGMAP. Each duplication encompasses more than 1 Mb of DNA and appears to be chromosome 11 specific. Ten STS markers were mapped within each duplication. Comparative sequence analysis along the duplication identified 35 nucleotide changes in 2,036 bp between the two copies, suggesting the duplication occurred over 14 million years ago. A suggested organization of the pericentromeric region, including the duplications and alpha-related repetitive sequences, is presented.