Biomedical subjects

W Bergler

Publications and source records attributed to W Bergler.

At least 37 records · Page 2Linked to original sources

PubMed1999

Argon plasma coagulation for the treatment of hereditary hemorrhagic telangiectasia.

OBJECTIVES: Patients with (HHT) often suffer from recurrent epistaxis, which poses considerable therapeutic problems. Theoretical considerations render argon plasma coagulation (APC) a promising new therapeutic approach. STUDY DESIGN: In a prospective study 12 patients (aged 8-68 y) who presented with a long history of treatment for epistaxis were treated with telangiectasia in the nasal mucosa. After 2 weeks and again after 4 months the treatment results were evaluated by questionnaire. METHODS: APC is based on high-frequency electric energy transmitted through ionized argon gas to the tissue in a noncontact mode. Coagulation and desiccation of tissue are limited to 1 to 2 mm of penetration and therefore risk of tissue damage is low. Coagulative effects are best in tissue with high electrical conductivity, especially blood vessels. RESULTS: All patients were satisfied with the postoperative results. Frequency and intensity of bleeding were significantly reduced. All patients reported better postoperative results than with any other treatment they had received previously. CONCLUSION: First clinical experience shows that APC is a useful alternative for the treatment of telangiectasia in the nasal mucosa and should be a therapeutic option for this disease.

Adolescent↗

PubMed1998

[Argon plasma coagulation in treatment of hereditary hemorrhagic telangiectasia of the nasal mucosa].

Patients with hereditary hemorrhagic telangiectasia (M. Osler-Rendu-Weber disease) often suffer from recurrent epistaxis that poses considerable therapeutic problems. Dermoplasty, electrocoagulation, laser coagulation, iridium brachytherapy and systemic administration of estrogens have been proposed for treatment. Until recently argon plasma coagulation (APC) was not used in ENT surgery, but theoretical considerations render APC a promising therapeutic method for controlling nasal bleeding. Coagulation of tissue is limited to 1-2 mm of penetration and therefore risk of damage to adjacent tissue is low. Effects are best in tissues with high electric conductivity, especially for coagulating bleeding lesions and blood vessels. We have now treated four patients with telangiectasias in the nasal mucosa who had long histories of treatment for epistaxis. The patients were satisfied with the postoperative results and the frequency and intensity of bleeding were significantly reduced. Initial clinical experiences show that APC is a useful alternative for the treatment of bleeding telangiectasias in the nasal mucosa.

Adult↗

PubMed1998

[Argon plasma surgery (APC) in the upper aerodigestive tract. Initial results].

Cold knife surgery, electrosurgery and laser surgery all offer techniques, instruments, equipment and systems for resecting and destroying mucosal lesions and for hemostasis in the upper aerodigestive tract. When used in the head and neck, argon plasma surgery (APS) offers a new, contact-free, electrosurgical technique in which high frequency current is applied through ionized, and thus electrically conductive, argon(argon plasma) to the tissue undergoing treatment. Especially noteworthy in APS are its advantages for removing a lesion and controlling bleeding: the technique is easy to control, and the depth of the thermal tissue destruction is limited to a maximum of 3 mm even in wide-area application, so that damage to adjacent or submucosal tissues can be avoided. Initial results with APS in the reduction of hyperplastic nasal turbinates, treatment of hereditary hemorrhagic teleangiectasia (Osler's disease) in the nasal mucosa, and in treating progressive juvenile papillomatosis of the larynx have shown clear advantages for APS over other methods used.

Adolescent↗

PubMed1998

Role of sialoglycan structures for the function of the epidermal growth factor receptor and the in vitro proliferation of head and neck cancer.

Squamous cell carcinomas of the head and neck have been found to show a high expression of the receptor for epidermal growth factor (EGF). This overexpression of the receptor has been associated with malignant transformation of cells, although there is still debate as to what extent this receptor takes part in the proliferation of malignant cells and which function it fulfills. The factors which determine receptor-ligand interaction are also not clearly defined. That the extracellular domain of the EGF receptor carries carbohydrate or sialoglycan structures might be important for function of the receptor. Since tumor specific enzymes can possibly alter such structures, it was the aim of our study to investigate the role of these structures on the EGF receptor during the proliferation of head and neck carcinomas. We used the human laryngeal squamous carcinoma cell line HLaC 79 and altered, for the first time, specific glycan structures with sialidase alpha-2,3 and alpha-2,6, causing desialylation. Changes were also produced by endo-beta-galactosidase and sialyltransferase. Findings were monitored by labeling with bromo-deoxyuridine. To determine receptor affinity, 125I-labeled EGF was employed. Results showed that both cell proliferation and receptor affinity depended on the level of sialylation of the receptor carbohydrate side chains. Desialylation led to a statistically significant reduction of tumor cell proliferation to 65 +/- 33% (P < 0.01), while receptor affinity decreased to 70 +/- 26% (P < 0.01). The importance of EGF receptor for the proliferation of malignant cells seems to depend on the level of sialylation of glycan structures on receptor protein. A release of enzymes by tumor cells may then produce auto-control of tumor proliferation on its own.

Binding Sites↗

PubMed1998

[Paranasal sinuses: only one of nature's games?].

BACKGROUND: Many theories exist concerning the function of paranasal sinuses, but it is rather difficult to definitively name the right one. Despite the fact that many of them have been proved to be wrong, they are still used. THEORIES: Galen postulated 2000 years ago that they were "porous bones", which helped with weight reduction. Like Galen's theory, most of the others have been refuted as well. A list of these refuted theories covers a range of postulated functions including a relative warming or moistening of the breath, protection against high pressure in the nasal region when sneezing, paranasal sinuses as a place of efficient mucus production, or an aid for smelling, similar to the ethmoidal cells of the porcupine. Others include an isolated function for protection against cold climates and an aid for formulating sound by acting as a resonance chambers. CONCLUSIONS: Two theories still remain. One says that the paranasal sinuses are only the result of the evolutionary processes that have taken place in the skull during human development. The other theory explain that the form of the paranasal sinuses exists through the influence of the forces created during the act of chewing. Small cavities appear as a result of the minimal energy created, and these cavities can be found in the form of paranasal sinuses.

Adaptation, Physiological↗

PubMed1998

The influence of an arterial and venous air embolism on the hearing level in laboratory mini pigs.

We examined the influence of an experimental venous and arterial air embolism on the hearing level in laboratory mini pigs. Before and after the injection of air a threshold ABR was measured in anaesthetized mini pigs (n=15). A venous air embolism was performed in 6 animals: no changes in the hearing level or in the interpeak latencies Jewett wave V-I were observed in any of the animals before, during or after the application of air. In 9 animals the arterial embolism was done, 2 animals died and had to be excluded. In 6 animals out of 7 a hearing loss was observed starting after the injection of 40 ml air and finally ending in deafness for these 6 animals. The detected hearing loss is probably of cochlear origin, as no prolongations of the interpeak latencies of Jewett wave V-I at 90 dB HL were observed prior to the deafness. Our results show that air bubbles in the arterial circulation lead to cochlear damage ending in deafness. Our research indicates that decompression sickness, which is comparable to the arterial air embolism, is more often the cause of a sensorineural hearing loss after diving than previously believed.

Animals↗

PubMed1998

[ETICS Study: Empirical therapy of idiopathic chronic singultus].

Idiopathic chronic singultus (ICS) describes recurring episodes of persistent hiccuping lasting longer than an arbitrary time limit (e.g. one month) for which no organic cause or consistently effective treatment can be found. It has been suggested that ICS may result from chronic stimulation of a supraspinal "hiccup center" by impulses originating from receptors in the gastrointestinaltract. This hypotesis implies the possibility of treating ICS by reducing gastric acid (via omeprazole), facilitating gastric emptying (via cisapride), or suppressing of the "hiccup centre" (via GABA-ergic offects of baclofen or gabapentin). 29 patients (28 male, one female; age 71 +/- 10 years) suffering from ICS for four to 564 months were treated with a combination of cisapride (30 mg/d), omeprazole (20 mg/d) and baclofen (45 mg/d) (COB). The patients rated the severity of hiccuping on a subjective assessment scale (SAS) that ranged from 0 (= no hiccuping) to 10 (= unbearable hiccuping). Hiccuping ceased in 38% (11/29) of the treated patients and decreased in severity in an additional 24% (7/29). Mean SAS-scores following 20 to 24 weeks of therapy (3.7 +/- 3.4) were significantly lower compared to before therapy (8.8 +/- 1.3) (Mann-Whitney rank order test [p < 0.02]). In the patients that failed to respond to COB, gabapentin (1.200 mg/d) was substituted for baclofen. Hiccuping ceased in one and improved in two of these ten subjects. We conclude that COB is an effective empirical therapy in the majority of patients with ICS. It may be useful to substitute gabapentin for baclofen in those not responding to COB.

Acetates↗

PubMed1997

[The treatment of juvenile laryngeal papillomatosis with argon plasma coagulation].

HISTORY AND CLINICAL FINDINGS: At 3 years of age a girl known for one year to have progressive juvenile laryngeal papillomatosis with involvement of the lower respiratory tract was seen by her general practitioner because of increasing hoarseness. As about 20 sessions of CO2-laser treatment and adjuvant administration of interferon-alpha had failed to prevent increasing glottal stenosis and spread of the tracheal involvement, a tracheostomy had to be performed. Removal of the papilloma became progressively more difficult and at the age of 6 years she was admitted for further treatment. INVESTIGATIONS: She had marked inspiratory and expiratory stridor. Results of laboratory tests were unremarkable. Examination of the respiratory tract with a flexible endoscope revealed obstruction of the tracheal lumen by the papilloma. TREATMENT AND COURSE: The papilloma was removed by argon plasma coagulation (APC) under general anaesthesia during intermittent apnoeic phases. After four treatment sessions no papilloma could be seen endoscopically. There were no side effects or complications. The interval between treatments has become progressively longer. Further removal of papilloma is only rarely necessary nowadays. CONCLUSION: APC via a flexible endoscope is a promising method in the treatment of juvenile laryngeal papillomatosis involving the lower respiratory tract. It achieves precise, circumscribed tissue penetration without carbonisation or steaming-up, while bleeding can be controlled.

Child, Preschool↗

PubMed1997

In vitro paraoxon (E 600) exposure: no activating effect on human blood coagulation.

The in vitro effects of the organophosphorus compound (OPC) paraoxon (POX) on human blood coagulation were assessed by fibrin monomer (FM) concentration measurements and thrombelastographic (TEG) determinations. Increasing doses of POX dissolved in alcohol (POX + ALO) or alcohol (ALO) only in corresponding quantities were added to blood drawn from six human volunteers. In both series (POX + ALO and ALO-only) FM concentrations increased in comparison to the baseline levels. No statistically significant differences exist, however, between FM measurements performed on blood with POX + ALO and those performed on blood with ALO-only. No coagulation-activating effect of POX in vitro was demonstrable; the changes seen in vitro are due to the ALO used as a vehicle. The thrombelastographic parameters showed several changes in the POX + ALO series as dosage increased. At high POX levels, reaction time r and clot formation time k became longer than in the baseline measurements, the clot formation rate alpha and the maximum amplitude MA were reduced. The TEG changes indicate a hypocoagulable state, probably due to the POX effect on platelet function and/or inhibition of clotting factors (serine proteases).

Blood Coagulation↗

PubMed1997

A new histobiochemical method to analyze sialylation on cell-surface glycoproteins of head and neck squamous-cell carcinomas.

Oncogenic transformation is often accompanied by alterations of glycosylation on a tumor cell's surface, which may contribute to uncontrolled cell growth. The sialoglycans and degree of sialylation on the cell surface are of increasing interest because of their possible role in metastasis and tissue invasion. Since primary tumors and metastases may differ in the degree of sialylation, we examined the expression of sialic acid as a terminal constituent of lactosaminyl glycans on the cell surfaces of 30 cervical lymph-node metastases and 30 squamous-cell carcinomas of the oropharynx and oral cavity. Cell-surface sialylation was determined by a new histobiochemical assay on cryostat sections and was based on the enzymatic introduction of a fluorescence-labelled sialic acid into lactosaminyl type (Gal-beta 1-4 GlcNAc) oligosaccharide chains of cell-surface-expressed glycoproteins. To this end, tissues were incubated in the presence of 5-acetamido-9-deoxy-9-fluoresceinyl-thioureido neuraminic acid (CMP-9-fluoresceinyl-NeuAc) and alpha-2,6-sialyltransferase. In order to compare the degree of sialylation with the potential total amount of sialylation sites, pretreatment with sialidase for desialylation was required. We observed a significantly higher amount of lactosaminyl-type binding sites for sialic acid on metastases compared to the primary tumors (P = 0.001), indicating a lower degree of sialylation in metastases. In primary tumors no correlation was seen between the amount of binding sites and tumor localization, TNM stage or histologic grading. Pretreatment of specimens with sialidase demonstrated a significant degree of sialylation on both primary tumors and lymph-node metastases, but no difference between primary tumors and metastases. When tumor stroma of primary tumors and metastases was compared, tumor cells showed a higher degree of free binding sites for sialic acid, but a low degree of sialylation. Our results suggest that differences in the degree of sialylation of glycoconjugates on a tumor cell's surface may play an important role in the process of cell metastasis. Our histobiochemical method turned out to be very reliable, effective and readily performed.

Binding Sites↗

PubMed1997

[The Mallampati Score. Prediction of difficult intubation in otolaryngologic laser surgery by Mallampati Score].

UNLABELLED: The Mallampati score (MS), later modified by Samsoon and Young, is a common method used to predict difficult intubation. We tested its predictive value in otolaryngologic (ENT) laser surgery. METHODS: Ninety-one patients scheduled for elective ENT laser surgery had the modified MS noted prior to induction in the supine position, with the tongue fully protruded and phonating "ah"; 22 patients were female, 69 male. The mean age was 54 +/- 15 (6-84) years, height 171 +/- 9 (130-190) cm, and weight 72 +/- 21 (20-99) kg. After a standard induction, the laryngoscopic view was graded according to Cormack and Lehane (C&L). An intubation was considered difficult if the C&L score was > or = 3, i.e., no part of the glottis seen during laryngoscopy. The hypothesis tested was that a MS > or = 3 (i.e., only the base of the uvula or nine of the uvula was seen) is predictive of difficult intubation in this group of patients. This chi-square test was used for calculation of significance. RESULTS: All intubations were performed in less than three attempts, and no C&L score of 4 (i.e., not even the epiglottis seen during laryngoscopy) was observed; 10 patients had a C&L score > or = 3, i.e., a difficult intubation according to our definition. Sixty-two patients had a MS < or = 2; of these, 4 (= 6%) were difficult to intubate. Twenty-nine patients had MS > or = 3; of these, 6 (= 21%) were difficult to intubate. This difference was significant (chi-square = 4.1, P < 0.05). CONCLUSION: Difficult intubation was significantly more common in patients with MS > or = 3. Low sensitivity (60%) and specificity (72%) limit the clinical value of this test, however.

Adolescent↗

PubMed1997

[Late sequelae of lateral and central mid-facial fractures after osteosynthesis with miniplates].

Despite significant progress in the therapy of craniofacial injuries permanent consequences of the trauma are still likely to occur. It has been possible to follow-up 105 (65.2%) of the 161 patients who were treated for lateral and central midfacial fractures in our department between 1989 and 1991. Pathological findings on follow-up were found in 48.6% of our patients. Most frequent were persistent disturbances of the sensitivity in the area of the second branch of the trigeminal nerve (32.4%). Patients who were operated within the first week after trauma did have significantly less sensory disturbances than patients who underwent surgery later. 7.6% of our patients had permanent double vision (4.8% in their primary vision field). After subciliary incision 3% had an ectropium which was not found after transconjunctival incision. There was no significant difference in the cosmetic outcome of the two approaches. In one patient who received silicone for restoration of the orbital floor the plate did migrate. Other materials that were used for orbital floor reconstruction did not cause problems. Based on the post-operative results improvements for the therapeutic regimen are discussed.

Adolescent↗

PubMed1997

[Difficult intubation in otorhinolaryngologic laser surgery. Is there a predictive parameter?].

In the planning of laser surgery for ENT operations, the specialist is often consulted by the anesthesiologist to predict possible intubation problems. Intubation problems in such operations can occur frequently due to the pathological findings present in the upper aerodigestive tract and the different constructions of laser-resistant endotracheal tubes. The aim of this study was to determine if a known predictive parameter could have a sufficient sensitivity and specificity to reliably predict possible intubation problems for ENT-related laser surgery. In a prospective study, 91 patients were included and the Mallampati-score modified by Samsoon and Young was analyzed and compared to a score describing the actual conditions of intubation. The results showed a significant correlation (p < 0.05, Chi-Square test). However, the specificity was only 72% and the sensitivity of 60% was too low to be of practical use. The results were independent of the endotracheal tube used. Although use of the laser for ENT operations provides a special situation for the anesthesiologist, there is still no system that is sensitive and specific enough to be of practical use. This problem is demonstrated in a literature review.

Adolescent↗

PubMed1997

Treatment of recurrent respiratory papillomatosis with argon plasma coagulation.

Extension of recurrent respiratory papillomatosis (RRP) to the lower airway in children is life-threatening and an extremely difficult condition to treat. We present the case of a seven-year-old girl with progressive RRP since the age of two. Repeated CO2 laser treatment and interferon-alpha treatment could not prevent tracheotomy and spread to the trachea. We used argon plasma coagulation (APC) with flexible endoscopy for the first time for the treatment of RRP. APC gives a controlled limited penetration into the tissue and good control of bleeding. There is no carbonization or vaporization which makes it a suitable method for the treatment of lower airway RRP. After a few treatments with APC, we gained very good control of the disease with no side-effects or complications. The described application of APC seems to be a promising way to treat lower airway RRP.

Child, Preschool↗

PubMed1997

[Reimbursement budgets and treatment demands require cost saving--a short operations day as a possible solution in the hospital].

BACKGROUND: Implementation of case related budgeting (similar to diagnosis related groups) has forced hospitals into more cost efficient management particularly with respect to surgery. Efforts to increase efficiency are concentrated on the labor intensive organization of the surgical ward. Operations of short duration are a major focal point. An analysis of the organizational structure of our hospital showed that significant improvement in operating theater management and utilization can be achieved in order to improve efficiency. A new pilot project was tested for economic efficiency. METHODS: On eleven specified surgery days (129 patients) only short operations with a duration of less than 20 min were allowed (tonsillectomy, adenectomy, etc.). On each day 15 operations were performed in one operating room with two anesthesiology teams and one surgery team. This type of "short-operation day" was compared with a "regular" surgery day with two operating rooms, two anesthesiology teams, and two surgery teams. Efficiency, complication rates, economic outcome, and patient satisfaction were assessed. RESULTS: Due to reduction of staff and a more efficient organization, we were able to reduce the costs for staff and the operating theater maintenance from DM 378,20 to DM 243,90 for each operation. Additionally, only one operating room was required instead of two. Complication rates (postoperative bleeding) were lower than before and patient acceptance and satisfaction was remarkable. CONCLUSIONS: Economic efficiency of short operations could be increased by organizational restricturing. The quality of the operations and the patients' satisfaction did not decrease.

Adolescent↗

PubMed1997

[New developments in endoscopy].

Beside the developments of new imaging modalities in endoscopy, efforts have been made to improve therapeutical possibilities of endoscopic interventions. In addition to the improvement or even development of new instruments for flexible and rigid endoscopy, the potentials of the new technique of argon-plasma-coagulation in ENT are only hardly discovered. This innovative method is based on high-frequency (HF) electric current for non contact tissue coagulation via ionized argon gas. It leads to a homogeneous coagulation and desiccation zone with a limited and controlled tissue penetration. In addition a multifunctional instrument is presented for the resection of tumors in the upper aero-digestive tract which is able to cut and coagulate tissue on an HF basis and is provided with a channel for suction and irrigation. Additional instruments are offered for the laser surgical resection of tumors through the microlaryngoscope. These instruments are equipped with a cable connection for HF current and are helpful for controlling and managing large bleeding tumor masses. The increasing significance of the flexible endoscopy in ENT surgery is being taken into consideration by the development of additional instruments to remove all kind of foreign bodies in the esophagus or tracheo bronchial system. Through the creation of new materials it is also possible to perform an endoscopic dilatation of esophageal or hypopharyngeal stenoses with a reduced risk of perforations.

Endoscopes↗

PubMed1996

Vocal function following laser and conventional surgery of small malignant vocal fold tumours.

In the described study, 26 patients after conventional cordectomy, and 27 patients after laser cordectomy were examined six months or more after the operation. Videolaryngostroboscopy revealed that patients after laser cordectomy more often phonate on purely glottic level (81 per cent) in comparison to patients after conventional cordectomy (19 per cent). Webs were more frequent and more extended after conventional cordectomy compared to endoscopic laser surgery. The maximal phonation time showed a very wide range with a mean value of 9 to 10 sec; there was no statistical difference between the groups of patients. Using Yanagihara's classification of sonograms, a better voice quality was measured after laser cordectomy than conventional cordectomy. The patients' estimation of their voice quality did not correlate with objective parameters.

Adult↗

PubMed1996

Correlation of transforming growth factor alpha and epidermal growth factor receptor in oropharyngeal carcinomas.

Previous studies have shown increasing evidence that TGF-alpha, a ligand for the often overexpressed EGF-receptor may be important for the oncogenesis and autocrine stimulation of the proliferation in head and neck cancers. The occurrence of TGF-alpha and its relation to the EGF-receptor still remain unclear. Twenty six specimens (primaries and metastasis) of oropharyngeal squamous cell carcinomas were investigated for the presence of transforming growth factor alpha (TGF-alpha), epidermal growth factor (EGF) and the EGF-receptor using a tissue extraction method and a "sandwich" immuno absorbent assay. In 77% of the specimens we found TGF-alpha, all had a significant amount of EGF-receptors, no EGF was found. No significant difference was noted for metastasis and primaries. No correlation was seen to the TNM stage and to the histological grading. There was an inverse statistical correlation between the TGF-alpha and the EGF-receptor concentration. High TGF-alpha concentrations were associated with low EGF-receptor concentration. Interestingly, even high TGF-alpha concentrations showed a lower limit of EGF-receptor concentrations which could not be passed. The present investigation gives a quantitative determination of the EGF-receptors and TGF-alpha in oropharyngeal carcinomas. The results indicate that a EGF-receptor/TGF-alpha complex could be functionally important for autocrine/paracrine stimulation.

Carcinoma↗