bluuebunny/crossref_metadata_2025 huggingface dataset:
Ofloxacin Levels after Intravitreal Injection
Authors: Öztürk Faruk , Kortunay Selim , Kurt Emin , Inan Ü. Übeyt , İlker S. Sami , Bascı Nursabah E. , Bozkurt Atila , Kayaalp S. Oǧuz
Published: April 2003

Purpose: This study was carried out to get an insight into the ofloxacin elimination after intravitreal injection in rabbits. We also studied the effects of trauma and inflammation on the vitreous ofloxacin levels after intravitreal injection of ofloxacin. Methods: A penetrating eye injury in the right eye was inflicted on 24 rabbits and another 12 animals were used as control. A standardized intraocular inflammation was induced by intravitreal injection of a suspension of Staphylococcus aureus in half of the traumatized eyes. Ofloxacin (200 µg/0.1 ml) was injected into the midvitreous cavity of both traumatized and control right eyes, and samples were obtained at 2, 8, 24 and 48 h after injection. Drug concentrations were measured using high-pressure liquid chromatography analysis. Results: Vitreous levels of ofloxacin were above the MIC90 at 2 and 8 h in all groups for most of the common microorganisms causing endophthalmitis and also at 24 h in traumatized-infected eyes. At the second hour, the mean vitreous concentrations of ofloxacin both in traumatized and traumatized-infected eyes were lower than that in the control eyes (p < 0.05). At 8 h, the mean vitreous concentrations of ofloxacin in the traumatized and in the traumatized-infected eyes were higher than that in the control eyes (p < 0.05). At 24 h, the mean ofloxacin concentration was higher in the traumatized-infected eyes than that in control (p < 0.01) and traumatized eyes (p < 0.05), and also higher in the traumatized eyes than that in the control eyes (p < 0.05). The mean ofloxacin concentrations in the traumatized and traumatized-infected eyes were significantly higher (p < 0.01) than those in the controls at 48 h. The elimination half-life of ofloxacin in the control eyes was 5.65 h and trauma and inflammation prolonged the half-life to 9.47 and 9.72 h, respectively. Conclusion: Clearance of ofloxacin is fast and appears to be reduced by trauma and inflammation. Therapeutic drug levels in traumatized-infected eyes were maintained up to 24 h. This may be an important pharmacokinetic advantage in treating endophthalmitis unless the dose used has local toxicity and allows a longer dose interval when the dose is repeated.
Regulatory Mechanisms in the Retinal and Choroidal Circulation
Authors: Delaey Christophe , van de Voorde Johan
Published: April 2003

The retina receives its nutrients from two separate circulations: retinal and choroidal circulation. This short overview describes the determinants in the regulation of these circulations. Retinal circulation is characterized by a low blood flow while flow in the choroid is high. The choroidal circulation is mainly controlled by sympathetic innervation and is not autoregulated. Retinal circulation lacks autonomic innervation, shows an efficient autoregulation and is mainly influenced by local factors. Local mediators released by endothelial cells and surrounding retinal tissue also have a substantial role in the regulation of retinal circulation.
Aqueous Humor and Serum Tumor Necrosis Factor-α in Clinical Uveitis
Authors: Santos Lacomba Manuel , Marcos Martín Carmen , Gallardo Galera José María , Gómez Vidal Maria Amparo , Collantes Estévez Eduardo , Ramírez Chamond Rafael , Omar M.M.
Published: April 2003

Objective: To study the local and systemic behavior of the tumor necrosis factor-α (TNF-α) in patients with active uveitis. Methods: TNF-α levels were measured in aqueous humor and peripheral blood samples using an enzyme-linked immunosorbent assay from 23 patients with uveitis and 16 control patients who had been operated on for uncomplicated cataracts. Results: Aqueous humor and sera of patients with uveitis showed higher levels of TNF-α than those of controls (p < 0.001). A comparison of cytokine levels between aqueous humor and sera showed significantly higher levels of TNF-α in serum than aqueous humor (p < 0.001). Correlation studies using the regression test for successive steps showed that serum TNF-α levels correlated with recurrent uveitis (r = 0.4150; p = 0.0489). Conclusions: TNF-α is a cytokine that participates actively in the pathogenesis of clinical uveitis. Our data emphasize the greater systemic than local participation of TNF-α. Finally, an elevated serum TNF-α seems to be associated with a recurrent pattern of uveitis.
What Is the Incidence of Occult Metastasis in Patients with Stage N₀ Cancers of the Head and Neck?
Authors: Ferlito Alfio , Devaney Kenneth O. , Devaney Stephanie L. , Rinaldo Alessandra
Published: April 2003

There is a large body of evidence in the European and US literature which argues forcefully that the presence of metastatic deposits within cervical lymph nodes is the single most significant independent adverse prognostic factor in patients with squamous-cell carcinomas of the head and neck. When all head and neck cancers are considered, ipsilateral lymph node metastases appear to decrease patient survival by as much as 50%; moreover, the presence of contralateral or bilateral cervical metastases reduces prognosis by an additional 50%. Patients with cervical metastases seem to be more likely to develop both distant metastases and local recurrences at the primary site.
Succinic Dehydrogenase Histochemistry As an Early Marker for Hair Cell Pathology
Authors: Fredelius Lars , Viberg Agneta , Canlon Barbara
Published: April 2003

Density measurements of succinic dehydrogenase (SDH) activity were obtained from the inner and outer hair cells on surface preparations obtained from the guinea pig cochlea. Guinea pigs were exposed to noise (3.85 kHz, 120 dB SPL, 22.5 min) and sacrificed 0, 4 or 24 h after the exposure. By 4 h after exposure, the first- and second-row outer hair cells already demonstrated an altered SDH activity. By 24 h after exposure, a significant decrease in SDH staining in both the inner and outer hair cells at a distance of 10–12 mm from the cochlear apex was demonstrated. After a 1-month recovery period, scanning electron microscopy confirmed the main lesion site to be at a distance of 10–12 mm. In addition, Hensen’s cells (supporting cells) at a distance of 10–12 mm from the apex were intensely stained by SDH after noise exposure, indicating an increase in oxidative metabolism. SDH staining in the Hensen’s cells from the unexposed cochleae was not found. In conclusion, our findings suggest that the early use of SDH histochemistry can predict later permanent damage to the organ of Corti.
Different Clinical Characteristics of Aminoglycoside-Induced Profound Deafness with and without the 1555 A→G Mitochondrial Mutation
Authors: Tono Tetsuya , Kiyomizu Kensuke , Matsuda Keiji , Komune Shizuo , Usami Shin-ichi , Abe Satoko , Shinkawa Hideichi
Published: April 2003

Recent genetic studies have shown that hereditary susceptibility to aminoglycoside antibiotics is caused by the 1555 A→G mitochondrial mutation. We found the 1555 mutation in 4 out of 68 postlingual deaf patients who were candidates for cochlear implantation. All 4 patients developed bilateral profound hearing loss following administration of aminoglycosides. The pedigree of the family shows exclusively maternal transmission of hearing impairment in each case. On comparison with neuro-otological findings from aminoglycoside-induced deaf patients without the 1555 mutation, four distinct characteristics were noted: (1) a progressive nature of hearing loss; (2) better residual pure-tone thresholds; (3) lower thresholds for electrical promontory stimulation, and (4) well-preserved vestibular function. Although other factors such as differing dosages and/or administration routes may also be involved, profound hearing loss associated with the 1555 mutation may be due to a different pathogenic mechanism, i.e., strial dysfunction rather than a direct insult to the hair cells.
Comparison of the TEMPO+ Ear-Level Speech Processor and the CIS PRO+ Body-Worn Processor in Adult MED-EL Cochlear Implant Users
Authors: Helms J. , Müller J. , Schön F. , Winkler F. , Moser L. , Shehata-Dieler W. , Kastenbauer E. , Baumann U. , Rasp G. , Schorn K. , Esser B. , Baumgartner W. , Hamzavi S. , Gstöttner W. , Westhofen M. , Döring W. , Dujardin H. , Albegger K. , Mair A. , Zenner H.P. , Haferkamp C. , Schmitz-Salue C. , Arold R. , Sesterhenn G. , Jahnke V. , Wagner H. , Gräbel S. , Bockmühl U. , Häusler R. , Vischer M. , Kompis M. , Hildmann H. , Radü H.J. , Stark T. , Engel A. , Hildmann A. , Streitberger C. , Hüttenbrink K.B. , Müller-Aschoff E. , Hofmann G. , Seeling K. , Hloucal U. , von Ilberg C. , Kiefer J. , Pfennigdorff T. , Gall V. , Breitfuss A. , Stelzig Y. , Begall K. , Hey M. , Vorwerk W. , Thumfart W. , Gunkel A. , Zorowka P. , Stephan K. , Gammert C. , Mathis A. , DeMin N. , Freigang B. , Ziese M. , Stützel A. , von Specht H. , Arnold W. , Brockmeier S.J. , Ebenhoch H. , Steinhoff A. , Zierhofer C. , Zwicknagl M. , Stöbich B.
Published: April 2003

A study was conducted to compare the new MED-EL TEMPO+ ear-level speech processor with the CIS PRO+ body-worn processor in the COMBI 40/COMBI 40+ implant system. Speech tests were performed in 46 experienced subjects in two test sessions approximately 4 weeks apart. Subjects were switched over from the CIS PRO+ to the TEMPO+ in the first session and used only the TEMPO+ in the time between the two sessions. Speech tests included monosyllabic word tests and sentence tests via the telephone. An adaptive noise method was used to adjust each subject’s scores to approximately 50%. Additionally, subjects had to complete a questionnaire based on their 4 weeks of experience with the TEMPO+. The speech test results showed a statistically significant improvement in the monosyllabic word scores with the TEMPO+. In addition, in the second session, subjects showed a significant improvement when using the telephone with the TEMPO+, indicating some learning in this task. In the questionnaire, the vast majority of subjects found that the TEMPO+ allows equal or better speech understanding and rated the sound quality of the TEMPO+ higher. All these objective and subjective results indicate the superiority of the TEMPO+ and are mainly attributed to a new coding strategy called CIS+ and its implementation in the TEMPO+. In other words, based on the results of this study, it appears that after switching over from the CIS PRO+ to the TEMPO+, subjects are able to maintain or even improve their own speech understanding capability.
Radical Meatoplasty in the Treatment of Severe Chronic External Otitis
Authors: Haapaniemi Jorma J. , Laurikainen Esa A. , Suonpää Jouko T.
Published: April 2003

In the beginning, external otitis is an inflammation of the skin of the external ear canal. Partial or total obliteration of the meatus causes cleaning problems, which worsen the obliteration, and hence, the infection. Immunosuppressive medication or illness, certain dermatological problems or frequent infections may lead to irreversible changes and to the malignant form of external otitis with life-threatening sequelae. Conservative treatments in the beginning are aimed at regaining the normal skin functions by helping the cleaning process and curing the acute infection with repeated irrigation, proper antibacterial medication and corticosteroids and anti-inflammatory analgesics. In rare prolonged cases, surgical procedures are needed to help the cleaning process by removing the irreversibly thickened skin and bone affections, and using grafts. On the basis of our experience, even the removal of the diseased skin and enlarging of the external ear canal are insufficient procedures in the most difficult cases. In the present paper, we describe a new surgical method that we have performed to treat chronic bilateral obliterative external otitis in 2 patients, with favorable results.
Pulsatile Audible Tinnitus and Metastatic Breast Carcinoma of the Temporal Bone
Authors: Vasama Juha-Pekka , Pitkäranta Anne , Piilonen Anneli
Published: April 2003

Metastases into the temporal bone are uncommon and typically present with trivial otological symptoms. We report a rare case of pulsatile audible tinnitus caused by metastatic breast carcinoma of the temporal bone.
Surgical Management of the Neck in Thyroid Cancer
Authors: Ferlito Alfio , Silver Carl E. , Pelizzo Maria R. , Rinaldo Alessandra , Toniato Antonio , Owen Randall P.
Published: April 2003

Thyroid cancer is a relatively common clinical problem. The American Cancer Society has estimated 1,050,000 newly diagnosed cancers in 1999 in the United States, of which 16,000 are expected to be of thyroid origin. Although most thyroid cancers have an excellent prognosis as compared with other malignant tumors, it is estimated that approximately 1,225 deaths will be attributed to the disease [1].
Chondroid Chordoma of the Lateral Skull Base
Authors: Rossiello Raffaele , Ferrara Gianpaolo , Varricchio Attilio , Baldi Alfonso , Motta Sergio , Motta Gaetano
Published: April 2003

A rare case of chondroid chordoma of the lateral skull base with laterocervical extension is reported. Clinical, radiological and pathological features of the tumor are described. This unusual location of chondroid chordoma enabled total resection of the neoplastic tissue through a combined laterocervical and far lateral transjugular approach.
Long-Term Results of Tracheostomy for Severe Obstructive Sleep Apnea Syndrome
Authors: Haapaniemi Jorma J. , Laurikainen Esa A. , Halme Perttu , Antila Jukka
Published: April 2003

Severe obstructive sleep apnea (OSAS) is most often accompanied by metabolic syndrome, obesity, diabetes and coronary disease. In its most severe form, it is a life-threatening condition, requiring active and immediate help. Nasal continuous positive airway pressure (CPAP) is the most efficient nonsurgical treatment for patients with OSAS. However, for anatomical, disease-related and subjective reasons, many patients cannot accept this treatment. A permanent tracheostomy may be one alternative in such patients who, in addition, often suffer from extreme obesity and severe heart disease. In this paper, we describe the long-term follow-up results of 7 patients suffering from OSAS and treated with permanent tracheostomy. All the patients (5 men, 2 women) were diagnosed using the static charge sensitive bed method and night-time oximetry for sleep analysis. The mean body mass index (BMI) of the patients ranged from 34 to 60 and the age from 41 to 64 years. All the patients had severe OSAS and long periods of low oxygen saturation (SaO2) levels. Six patients had a CPAP trial before tracheostomy. Only 2 patients tolerated the trial but, despite the continuous use of CPAP, they were nonresponders. Permanent tracheostomy was done according to normal routine in each patient. After primary healing of 2 days, they used silver cannulae, which also allowed them to speak. The patients were evaluated every year after the tracheostomy. After some practical difficulties including proper maintenance of the cannula, all the patients quickly learned the correct management. In postoperative sleep studies, nadir SaO2 levels had improved significantly, obstructive apneas had disappeared and the subjective quality of life had improved. No marked changes in BMI were found.
The Biology of Distant Metastases in Head and Neck Cancer
Authors: Petruzzelli Guy J.
Published: April 2003

The detection and treatment of metastatic cancer continues to be a challenge for the head and neck oncologist. Unfortunately, head and neck cancer patients who develop distant metastases commonly present late in their course and rapidly succumb to their disease, despite advances in imaging technologies and increased sophistication of biochemical analyses. The development of a rational approach to detection and treatment of metastatic head and neck cancers should begin with an understanding of how these tumors occur and which patients are at greatest risk for developing them. This article presents an overview of the biological processes resulting in the speed of a malignancy from one site to another, with particular attention to head and neck carcinomas. The basic histopathologic, immunology and biochemical abnormalities associated with the development of these secondary tumors are also discussed.
Screening Tests to Evaluate Distant Metastases in Head and Neck Cancer
Authors: Ferlito Alfio , Buckley J. Graham , Rinaldo Alessandra , Mondin Vanni
Published: April 2003

Investigation for distant metastases is part of the staging process of a primary tumor or recurrent disease before treatment. The lung is the most frequent site followed by bone and liver. Advanced stage and cervical metastases are the most important predictors of metastases. Almost all distant metastases are associated with lung metastases. Computed tomography scan of the chest is the single most effective investigation. The value of routine screening tests is questionable and merits further investigation.
Distant Metastases from Oropharyngeal Cancer
Authors: Goodwin W. Jarrard
Published: April 2003

Distant metastasis is a significant problem in patients with carcinoma of the oropharynx, occurring in approximately 15–20% off all patients over the course of the disease. It is, however, a relatively uncommon first site of failure, as compared to local and regional recurrence. Distant spread occurs most commonly to the lungs, in patients who present with advanced disease, and especially in those with pathologically proven lymph nodes at multiple levels of the neck or in the lower neck. Metastasis to distant sites also occurs more often in patients who recur locally or in the neck.
Distant Metastases from Cervical Esophagus Cancer
Authors: Bresadola Fabrizio , Terrosu Giovanni , Uzzau Alessandro , Bresadola Vittorio
Published: April 2003

Cancer of the cervical esophagus has a poor prognosis in relation to stage. Correct staging is thus essential in order to establish the prognosis and the treatment program. Distant metastases can involve the lymph nodes (mediastinal and celiac lymph nodes) or they can be extranodal visceral types. Correct lymph node staging can be performed with esophageal endoscopic ultrasonography, computed tomography (CT) scan and, currently, with positron emission tomography (PET) and minimally invasive surgery. For hematogenous metastases, CT scan and PET are mainly used, as well as minimally invasive surgery, with the eventual aid of intraoperative ultrasonography.
Aldosterone Assessment in Patients with Menière’s Disease
Authors: Mateijsen D.J.M. , Kingma C.M. , de Jong P.E. , Wit H.P. , Albers F.W.J.
Published: April 2003

Since 1938 endolymphatic hydrops has generally been accepted as the basic histopathological substrate of Menière’s disease. In animal studies it has been found that exogenous administration of aldosterone resulted in endolymphatic hydrops. Manifestations of Menière’s disease are frequently observed in times of emotional stress. Mediated through the hypothalamus, stress leads to an increased secretion of adrenocorticotropic hormone from the anterior pituitary gland, followed by an increased adrenocortical production of glucocorticoids (cortisol and corticosterone) and mineralocorticoids (aldosterone). We addressed the question whether plasma aldosterone levels, like in guinea pigs, would be increased in patients with Menière’s disease. As part of a diagnostic protocol a clinical prospective cohort study was therefore performed on 89 patients with Menière’s disease to assess plasma aldosterone levels. Plasma aldosterone was not elevated in Menière patients compared to plasma aldosterone in a control group of 27 normal subjects. No statistically significant differences were found in plasma aldosterone between uni- and bilateral Menière’s disease. Plasma aldosterone levels did not correlate with age, average hearing loss, duration or perceived severity of subjective complaints (vertigo, hearing loss, tinnitus and aural pressure). In this study plasma aldosterone was not elevated in patients with Menière’s disease compared to normal subjects. Plasma aldosterone can thus not be used as a diagnostic tool for Menière’s disease. In conclusion: No anomalous plasma aldosterone levels were found in Menière patients during an attack-free period. The question whether plasma aldosterone and cortisol levels show variations before, during and after an attack remains to be answered. If so, this might contribute to a better understanding of the pathophysiological mechanism of Menière’s disease.
Endoscopic-Assisted Myringoplasty
Authors: Usami Shin-ichi , Iijima Naoya , Fujita Shigetoshi , Takumi Yutaka
Published: April 2003

An improved myringoplasty technique utilizing fibrin glue and carried out through the external auditory canal was recently introduced. This endoscopic-assisted technique allows exquisite views and avoids blind surgical procedures, thereby expanding the indications for minimally invasive myringoplasty. This technique was applied to patients in whom, due to the curved external auditory canal, the margin of the perforation of the tympanic membrane was not visible with an operating microscope. We summarized the results of 22 endoscopic-assisted myringoplasties and concluded that this technique provides satisfactory results both in the success rate of perforation closure and in hearing outcome.
Inflammatory Myositis: A Rare Differential Diagnosis of a Neck Lump
Authors: Tsikoudas A. , England R.J.A. , Fenwick J.D. , Sampson H.
Published: April 2003

Inflammatory myositis is an extremely rare benign inflammatory condition of skeletal muscle. It usually affects the extremities, and there are only 10 cases reported in the head and neck region. Its significance is that in this region it can be clinically mistaken for a neoplasm. We describe a case and review the literature.
Endonasal Approach for Nasal and Paranasal Sinus Tumor Removal
Authors: Kühn Uta M. , Mann Wolf J. , Amedee Ronald G.
Published: April 2003

Patients with benign (53) and malignant (22) tumors of the nose and paranasal sinuses were treated for tumor removal via an endonasal approach. Patient selection was based on tumor location (centrally) rather than histology. Tumors attainable by the endonasal approach were located in the nasal cavity, the ethmoid sinus, the sphenoid sinus and the medial wall of the maxillary sinus. Endonasal microscopic techniques including endonasal orbital decompression and endonasal closure of CSF-leaks were combined with surgical navigation tools in selected cases. Surgical trauma and morbidity could be minimized without compromising radicality of tumor removal. Postoperative hospitalization was comparable to the period needed after chronic inflammatory disease. Growing experience with endonasal techniques is leading towards a safe and effective treatment option for centrally located, selected tumors of the nose and paranasal sinuses.
Lacrimal Gland Abscess: An Unusual Complication of Rhinosinusitis
Authors: Mirza S. , Lobo C.J. , Counter P. , Farrington W.T.
Published: April 2003

We report the case of a 72-year-old female suffering from mild myelodysplasia who initially presented with a peri-orbital cellulitis secondary to rhinosinusitis. The pre-septal infection failed to completely resolve despite intensive antibiotic therapy and endoscopic drainage of the sinuses. Computerised tomography revealed a complicating suppuration of the lacrimal gland. Incision and drainage of the lacrimal gland abscess led to a complete resolution of the pre-septal cellulitis. Suppuration of the lacrimal gland is, as far as we are aware, a previously unreported complication of rhinosinusitis. Its presence could be borne in mind when evaluating computerised tomography scans of patients presenting with orbital complications of sinusitis, particularly in the immunocompromised.
Hypoxia-Induced Tumour Cell Migration in an in vivo Chicken Model
Authors: Plasswilm L. , Tannapfel A. , Cordes N. , Demir R. , Höper K. , Bauer J. , Höper J.
Published: April 2003

To investigate the relationship between hypoxia, neovascularisation and tumour cell spread, experiments on the area vasculosa of the early chick embryo under different oxygen concentrations were performed in vivo. Human glioblastoma cells (U-138MG) were inoculated onto the area vasculosa and the fertilised eggs were incubated under conditions of normoxia or hypoxia. For evaluation, we performed in vivo video-microscopy of the area vasculosa and determination of microvessel density (MVD), as well as a histological examination of the fixed specimen. Under hypoxia, MVD was significantly increased compared to normoxic conditions. Only under hypoxic conditions was tumour cell spread found outside the main tumour mass and within the vessels, at times followed by the subsequent development of secondary tumour cell bulks on the area vasculosa. These data lead to the conclusion that hypoxia can stimulate tumour cell migration in this in vivo model.
Increased Cell Surface Expression of Receptors for Transforming Growth Factor-β on Osteoblasts from Patients with Osteogenesis imperfecta
Authors: Gebken J. , Brenner R. , Feydt A. , Notbohm H. , Brinckmann J. , Müller P.K. , Bätge B.
Published: April 2003

Osteogenesis imperfecta (OI) is a heritable connective tissue disorder usually characterized by either a reduction in the production of normal collagen I or the synthesis of abnormal collagen. The variability in the clinical phenotype is not in each case sufficiently explained by the underlying mutation in the collagen I genes. Also, biochemical differences between mutant collagen from different tissues suggest additional regulatory mechanisms possibly involved in matrix deposition and maturation, two processes in which transforming growth factor-β (TGF-β) plays an important role. We, therefore, studied the cell surface expression and functional properties of TGF-β receptors I, II and III on osteoblasts from a group of OI patients compared to healthy controls. Receptor number and affinity were determined by Scatchard analysis of binding data and TGF-β receptor II gene expression was assessed by RT-PCR. Ligand-induced downregulation of TGF-β receptors was analyzed to demonstrate the dynamic response to exogenous stimuli. All experiments were performed in parallel in human osteoblastic cells from OI patients and from age-matched controls. TGF-β receptors I, II and III (betaglycan) were present on osteoblasts from both healthy donors and OI patients. The receptor numbers were significantly higher (29,000 per cell) on OI osteoblasts than on age-matched control osteoblasts (12,000 per cell) in spite of similar steady state levels for TGF-β receptor II mRNA in OI and control cells. Furthermore, receptor affinity was not significantly different in OI osteoblasts (181 vs. 177 nM–1), and the receptor number did not depend on the culture substrate. With respect to dynamic adaption, ligand-induced downregulation of TGF-β receptors was reduced in OI osteoblasts. In conclusion, the human osteoblastic cells from patients with OI investigated all have an elevated number of cell surface receptors for TGF-β, without any evidence for a transcriptional regulation of TGF-β receptor II. On the functional level, there is some evidence for an impaired adaptive behavior of receptor presentation, whereas receptor affinity is unchanged.
Effect of Heat-Pretreatment on Interleukin-2-Activated Killer Cells for in vitro Purging
Authors: Tanaka M. , Honda J. , Imamura Y. , Shiraishi K. , Tanaka K. , Oizumi K.
Published: April 2003

Objective: Lymphokine-activated killer activity is effective in purging residual malignant cells from autologous bone marrow (BM) or leukapheresis collections for peripheral blood progenitor cells (PBPC). In this study, the effect of additional heat pretreatment on IL-2-activated cytotoxicity was examined. Methods: Nonadherent mononuclear cells from peripheral blood (PB), PBPC collections or BM were exposed to the desired temperature for 1 h, and successively cultured for 7 days in the presence of 1,000 units/ml of recombinant human interleukin-2 (IL-2). Cytotoxicity of IL-2-activated cells was determined by flow cytometry, using PKH-26-labelled K-562 or Raji target cells, and the cell surface antigens were also analyzed. Results: IL-2-activated cells from all specimens showed a distinct generation of cytotoxic activities. The activities were significantly decreased by heat at 42°C, but not changed by heat pretreatment at 40°C. In the surface expression of IL-2-activated cells, the increase of CD56+ cells from PB, PBPC collections and the decrease of CD28 cells from PBPC collections were shown to be significant (p < 0.05), but these changes were not found when the cells were heat-pretreated at 42°C. Discussion: These results suggested that a tumor-killing therapeutic temperature (≧42°C) may lead to a disadvantage in posttransplantation immunity, and that this reduction of IL-2-activated cytotoxicity may partly be due to a lack of the enhancement of CD56+ cells or the reduction of CD28+ cells.
Oligoclonality of Early Lesions of the Urothelium as Determined by Microdissection-Supported Genetic Analysis
Authors: Stoehr Robert , Hartmann Arndt , Hiendlmeyer Elke , Mürle Kristin , Wieland Wolfgang , Knuechel Ruth
Published: April 2003

Aim: To contribute to the ongoing discussion of clonality of human urothelial cancer it was considered a valuable approach to analyze multiple areas from cystectomy specimens for deletions of chromosomes known to be involved early in bladder cancer development. Material and Methods: Thus, in 86 biopsies of 4 human cystectomies with different histological findings (maximal diagnosis: pT1G2, pTaG3, pT2G2, normal) loss of heterozygosity (LOH) was investigated as a deletion marker using markers of chromosomes 8p, 9p, 9q and 17p. Findings were compared to histology of the lesion. Results: Findings indicate: (1) no changes in the markers investigated in the bladder with histologically normal urothelium in contrast to detection of LOH in normal urothelium of tumour-bearing bladders; (2) an accumulation of the number of LOH with increasing malignancy of lesions within one bladder, and (3) indications of oligoclonal neoplastic lesions in two of the urinary bladders investigated. Conclusions: The investigation of multiple lesions within one bladder presents a snapshot of genetic changes in differently advanced tumour stages. The hypotheses of tumour evolution and oligoclonality as derived from our LOH data need to be supported by deletion-independent clonality studies as X-chromosomal inactivation analysis.
Detection of Gene Amplification in Intraductal and Infiltrating Breast Cancer by Laser-Assisted Microdissection and Quantitative Real-Time PCR
Authors: Glöckner Sabine , Lehmann Ulrich , Wilke Nadine , Kleeberger Wolfram , Länger Florian , Kreipe Hans
Published: April 2003

Gene amplification is one essential mechanism leading to oncogene activation which is supposed to play a major role in the pathogenesis of invasive breast cancer. However, using standard methodologies the detection of gene amplifications has been limited especially in small-sized lesions, like pre-invasive precursor lesions. The combination of two novel technologies, laser-based microdissection and quantitative real-time PCR, facilitates the detection of low-level amplifications in morphologically defined lesions. As a model system we investigated in situ breast cancer (ductal carcinoma in situ, DCIS) classified according to the morphology-based Van Nuys grading system for amplification of growth-regulatory genes. In this study 83 formalin-fixed, paraffin-embedded archival DCIS specimens were examined after laser-based microdissection by quantitative real-time PCR using the TaqMan® detection system for amplification of the c-erbB2, topoisomerase IIα, c-myc and cyclinD1 gene. In a subset of 17 DCIS with adjacent infiltrating tumour components we compared intraductal and invasive tumour components in parallel for differences in amplification status. The combination of these new techniques represents an excellent tool to gain new insights into carcinogenesis by analyzing genetic alterations in morphologically identified heterogeneous lesions in breast cancer progression within the very same specimen or even tissue slide.
Laser-Assisted Microdissection and Short Tandem Repeat PCR for the Investigation of Graft Chimerism after Solid Organ Transplantation
Authors: Kleeberger Wolfram , Rothämel Thomas , Glöckner Sabine , Lehmann Ulrich , Kreipe Hans
Published: April 2003

The detection of donor-derived cells in the blood and tissues of graft recipients after solid organ transplantation is a readily observed phenomenon called microchimerism. Yet very little is known about the persistence and integration of recipient-derived cells in the transplanted organ, indicating a form of intragraft chimerism. To further study this phenomenon and its possible influence on graft acceptance or rejection, we developed the following novel approach. Immunohistochemically labeled cells were isolated by means of laser-based microdissection and subsequent laser pressure catapulting from paraffine-embedded posttransplantation biopsies. The following use of a highly sensitive PCR assay analyzing one polymorphic short tandem repeat (STR) marker enabled us to clearly identify the genotypes in samples containing as little as 10 isolated cells. The combination of laser-based microdissection and STR-PCR thus provides a powerful tool for the genotyping of even very few cells isolated from routinely processed biopsies after solid organ transplantation.
Diagnosis of Papillary Thyroid Carcinoma Is Facilitated by Using an RT-PCR Approach on Laser-Microdissected Archival Material to Detect RET Oncogene Activation
Authors: Lahr G. , Stich M. , Schütze K. , Blümel P. , Pösl H. , Nathrath W.B.J.
Published: April 2003

Objective: The purpose of this study was to investigate the value of the expression of the RET oncogene (rearranged during transfection) in papillary thyroid carcinomas (PTC) and its variants in the differential diagnosis of thyroid neoplasias. According to the literature RET oncogene activation by chromosomal rearrangements has been exclusively implicated in PTCs. Methods: To establish the incidence of RET activation in PTCs we used 5- to 10-µm sections from archival paraffin blocks. Either parts of the tissue slices were manually dissected or a few distinct cells were microdissected by laser-mediated manipulation with the Robot-MicroBeam system. RNA was extracted from paraffin-embedded thyroid tumors and the corresponding normal tissue. RT and nested PCR were performed using primers for RET/PTC1, PTC2 and PTC3, or for RET exons 12 and 13. PCR products were resolved by gel electrophoresis. Results: We detected RET transcription in approximately 85% of the PTCs including follicular variants and in isolated cells of the same tissues, but not in nonmalignant thyroid tissue. Conclusions: Our method may serve as an additional diagnostic tool to characterize ambiguous neoplasias and to identify especially nonpapillary, i.e. follicular tumors, as papillary carcinomas. Additionally, this study has demonstrated that expressed genes can be analyzed from routine histopathological tissue slides or pooled single cells. Large retrospective studies can also be performed with this method.
Microsatellite Instability in Tumor and Nonneoplastic Colorectal Cells from Hereditary Non-Polyposis Colorectal Cancer and Sporadic High Microsatellite-Instable Tumor Patients
Authors: Dietmaier Wolfgang , Gänsbauer Susanne , Beyser Kurt , Renke Birgit , Hartmann Arndt , Rümmele Petra , Jauch Karl-Walter , Hofstädter Ferdinand , Rüschoff Josef
Published: April 2003

Genetic alterations such as loss of heterozygosity (LOH) and microsatellite instability (MSI) have been frequently studied in various tumor types. Genetic heterogeneity of nonneoplastic cells has not yet been sufficiently investigated. However, genomic instability in normal cells could be a potentially important issue, in particular when these cells are used as reference in LOH and MSI analyses of tumor samples. In order to investigate possible genetic abnormalities in normal colorectal cells of tumor patients, MSI analyses of normal colonic mucosa were performed. Up to 15 different laser-microdissected normal regions containing 50–150 cells were investigated in each of 15 individual microsatellite-stable, sporadic high microsatellite-instable (MSI-H) and hereditary non-polyposis coli cancer (HNPCC) colorectal cancer patients. Frequent MSI and heterogeneity in the MSI pattern were found both in normal and tumor cells from 10 HNPCC and sporadic MSI-H tumor patients whose tumors had defect mismatch repair protein expressions. This observation shows that MSI can also occur in nonneoplastic cells which has to be considered in MSI analyses for molecular HNPCC screening. In addition, considerable genetic heterogeneity was detected in all MSI-H (sporadic and HNPCC) tumors when analyzing five different regions with less than 150 cells, respectively. These differences were not detectable in larger tumor regions containing about 10,000 cells. Thus, heterogeneity of the MSI pattern (e.g. intratumoral MSI) is an important feature of tumors with the MSI-H phenotype.
Stimulation of Glycosaminoglycan Biosynthesis by Umbilical Cord Serum of Newborns Delivered by Mothers with EPH Gestosis (Preeclampsia)
Authors: Romanowicz Lech , Bańkowski Edward , Jaworski Stefan
Published: April 2003

Objective: Edema, proteinuria, hypertension (EPH) gestosis, also known as preeclampsia, is the most common, pregnancy-associated pathological syndrome. It is accompanied by a significant increase in collagen content in the umbilical cord arteries and early replacement of hyaluronic acid by sulfated glycosaminoglycans (GAGs) both in these arteries and in Wharton’s jelly. Such a remodelling of the umbilical cord tissues is accompanied by an increase in insulin-like growth factor-I (IGF-I) concentration in the umbilical cord serum. Methods: Contact-inhibited human fibroblasts were incubated in Dulbecco culture medium containing control or EPH umbilical cord serum and supplemented with 14C-glucosamine or 35S-sulfate. Radioactive GAGs were isolated, submitted to electrophoretic fractionation and quantified. Results: The presence of umbilical cord serum in culture medium strongly stimulated the incorporation of 14C-glucosamine and 35S-sulfate into GAGs synthesized by these cells. EPH serum was much more active in stimulation of sulfated GAGs biosynthesis than control serum, whereas the biosynthesis of hyaluronic acid was stimulated by both sera to a similar degree. Conclusion: Since IGF-I is known as a stimulator of collagen and sulfated GAG biosynthesis, the high concentration of this growth factor in the umbilical cord plasma may be responsible for preeclampsia-associated remodeling of the umbilical cord.
A Theoretical Model of Benign External Hydrocephalus That Predicts a Predisposition towards Extra-Axial Hemorrhage after Minor Head Trauma
Authors: Papasian Nora C. , Frim David M.
Published: April 2003

Introduction: There is controversy over whether there exists a predisposition towards bleeding into the subdural space in infants with benign external hydrocephalus (BEH) or other enlargement of the extra-axial space (e.g. subdural hygroma). The presumed etiology implicates shear forces in over-stretching the extra-axial blood vessels. We have created a model of the intracranial space that approximates certain aspects of BEH. Using this model, we predict situations where children with BEH will bleed into the extra-axial space when normal infants will not. Methods: The cranial model consists of two spheres representing the brain and the skull. The distance between them represents the width of the extra-axial space. The spheres are concentric (with interspheric distance equal to N) in the normal condition and nonconcentric in BEH. In BEH, the distance between the two spheres varies from N to Q (0 < N ≤ Q) over a 906 M ≤ Q, with the translation orthogonal to the vector of N and parallel to that of M or vice versa), then the final length Vf of a vein V is Vf = (N2 + M)1/2, and the stretch ratio Vf/Vi is: Vf/Vi = (N2 + M2)1/2/N·Si, with Si the slack factor, where i represents either n for normal or b for BEH and M = N in the normal condition. Results: Given an equivalent capacity of veins to resist stretch injury (based on the proportion of change in length), for brain translations after a low-impact head injury, stretch ratios for BEH veins range from 1.677 to 3.436, whereas in the normal condition they range from 1.061 to 1.179. Therefore, for an increase in subarachnoid space from 3 (normal) to 6 mm (BEH), brain translocation in BEH will stretch veins beyond an average breaking point when the translation for the normal condition will not. Conclusions: Mathematical modeling of the cranial vault produces a relationship between venous stretch and the width of the extra-axial space. These equations predict an increased frequency of venous stretch injury in the situation of widened extra-axial space. Such venous injury is consistent with forces generated by minor trauma. This relationship, as predicted by our model, could underlie a predisposition towards extra-axial bleeding after minor head trauma in infants with BEH.
Continuous Remifentanil for Pediatric Neurosurgery Patients
Authors: German John W. , Aneja Rajesh , Heard Christopher , Dias Mark
Published: April 2003

Objective: Remifentanil hydrochloride is a new titratable opioid agonist with rapid onset and offset of action. We present 2 cases of intracranial mass lesions in whom remifentanil was used to obtain serial neurological examinations. Methods: Patients received bolus doses of remifentanil 1 µg/kg followed by continuous infusions of 0.1–0.5 µg/kg/min, titrated to effect. After the clinical examination, the remifentanil was restarted to the desired effect. Conclusion: The ultra-short duration of action of remifentanil makes it ideally suited for selected pediatric neurosurgical patients in whom frequent, serial neurological examinations are necessary. There were no side effects associated with the use of remifentanil.
Long-Term Follow-Up Data from the Shunt Design Trial
Authors: Kestle J. , Drake J. , Milner R. , Sainte-Rose C. , Cinalli G. , Boop F. , Piatt J. , Haines S. , Schiff S. , Cochrane D. , Steinbok P. , MacNeil N.
Published: April 2003

Background: A previously reported multicenter randomized trial assessed whether 2 new shunt valve designs would reduce shunt failure rates compared to differential pressure valves. The study did not show a significant difference in the time to first shunt failure. Patients entered the trial between October 1, 1993, and October 31, 1995. The primary results were based on the patients’ status as of October 31, 1996 (a minimum follow-up of 1 year). This report describes the late complications based on the patients’ most recent follow-up. Methods: Three hundred and forty-four hydrocephalic children at 12 North American and European centers were randomized to 1 of 3 valves: a standard differential pressure valve; a Delta valve (PS Medical-Medtronic) or a Sigma valve (NMT Cordis). Patients were followed until their first shunt failure. Shunt failure was defined as shunt surgery for obstruction, overdrainage, loculation or infection. If the shunt did not fail, follow-up was continued until August 31, 1999. Results: One hundred and seventy-seven patients had shunt failure. Shunt obstruction occurred in 131, overdrainage in 13, loculated ventricles in 2 and infection in 29. The overall shunt survival was 62% at 1 year, 52% at 2 years, 46% at 3 years, 41% at 4 years. The survival curves for the 3 valves were similar to those from the original trial and did not show a survival advantage for any particular valve. Conclusions: Prolonged follow-up to date does not alter the primary conclusions of the trial: there does not appear to be one valve that is clearly the best for the initial treatment of pediatric hydrocephalus.
Telemetric Assessment of Intracranial Pressure Changes Consequent to Manipulations of the Codman-Medos Programmable Shunt Valve
Authors: Frim David. M. , Lathrop Dawn
Published: April 2003

Introduction: Noninvasive manipulation of programmable shunt valves may allow customization of intracranial pressure (ICP) dynamics in individual shunted patients. Manipulations of the recently FDA-approved Codman-Medos variable pressure valve (VPV) are monitored by radiographic changes in the valve mechanism, necessitating a skull radiograph with each pressure change. We wished to assess the in vivo impact of VPV manipulations on ICP changes using a noninvasive telemonitor as an alternative to radiographic confirmation and as a method for validating the ICP changes. Methods: TeleSensor devices (Radionics) were implanted in-line with 12 VPV shunt systems. ICP was assessed telemetrically in the supine position whenever the valve pressure was adjusted (both before and 2–5 min after the manipulation). Results: Valve manipulation was confirmed by radiograph for the initial manipulations only and matched the telemetric pressure changes observed in all cases. Confirmed manipulations of the valve were generally followed by a near equivalent relative change in ICP (≤2 cm difference 74% of the time); however, the absolute value of the supine ICP was dependent on the entire shunting system and was equivalent to the valve setting only 11% of the time. Supine ICP and ICP dynamics were also dependent more on the shunt system than simply on the valve setting and were different for each of the shunt systems tested. Conclusions: We have confirmed that the VPV does cause ICP changes in shunted hydrocephalic patients that are essentially equivalent to programmed relative changes in the valve settings. These changes can be as easily monitored by noninvasive telemetry as by repeated radiography. However, our observations demonstrate that additional factors in the shunting system render the ICP absolutely equivalent to the VPV setting only rarely, implying that a programmable shunt valve is not necessarily equivalent to programmable ICP.
Amniotic Fluid Exchange for the Prevention of Neural Tissue Damage in Myelomeningocele:An Alternative Minimally Invasive Methodto Open in utero Surgery
Authors: Olguner Mustafa , Akgür Feza M. , Özdemir Tunç , Aktuğ Tanju , Özer Erdener
Published: April 2003

Objective: Experimental studies have shown that neural tissue damage in myelomeningocele (MMC) is acquired, resulting from exposure of neural tissue to amniotic fluid (AF). Similar to neural tissue damage in MMC, in gastroschisis, intestines exposed to AF are damaged. In gastroschisis, intestinal damage can be prevented by changing the composition of the AF with partial AF exchanges. An experimental study was performed to investigate whether the neural tissue damage in MMC can be prevented by AF exchange. Methods: Thirteen-day-old fertilized chick eggs were used. In group 1, the amnio-allantoic membrane was opened to create a common cavity, and MMC was created (MMC-only group). In group 2, after creation of MMC, amnio-allantoic fluid exchange was performed (MMC-plus-exchange group). Chicks were extirpated for histopathologic examination 5 days later. Results: While edema, focal calcification, fibrosis, capillary cell proliferation and scattered mononuclear cells were observed in the MMC-only group, histopathologic changes were mild in the exchange group. The number of neuron-specific enolase stainings (+) neural cell count was significantly higher in the exchange group compared to the MMC-only group (p < 0.01). Conclusion: Exposure of MMC to AF causes structural neural tissue damage that can be prevented by AF exchange. AF exchange is minimally invasive compared to open in utero surgery for the closure of MMC. By AF exchange, neural tissue damage that occurs during the gestational period may be prevented.