Enamel loss associated with orthodontic adhesive removal on teeth with white spot lesions: an in vitro study.

Teeth with white spot lesions (WSL) might be more prone to enamel loss during bracket debonding. This in vitro study compared enamel loss from teeth with (n = 14) and without (n = 14) WSL after polishing with low-speed finishing burs or disks (Sof-Lex, 3M ESPE, St Paul, Minn). Debonded surfaces were analyzed with a contact stylus profilometer, and digitized data were compared with baseline readings by using AnSur NT software (Regents, University of Minnesota, Minneapolis, Minn). Specimen surfaces were also examined with a scanning electron microscope. Two-way analysis of variance was performed to analyze the data. In teeth without WSL, the volume losses were 0.16 mm(3) for the bur group and 0.10 mm(3) for the disk group; the mean maximum depths were 47.7 microm for the bur group and 54.3 microm for the disk group. In teeth with WSL, the volume losses were 0.06 and 0.17 mm(3), and the mean maximum depths were 35.1 and 48.7 microm for the bur and disk groups, respectively. There were no significant differences in enamel loss between the 2 groups of teeth without WSL (P =.12). However, in teeth with WSL, the burs removed less enamel than the disks (P = 0.006). Scanning electron microscope examination showed that any damage on the enamel surface was usually located in the cervical third of the teeth. On most specimens, even though tooth surfaces appeared resin-free to the naked eye, there were remnants of it. The differences between groups were so small that they might be clinically insignificant.     

Thromboembolic and inflammatory complications of knee joint alloplasty with cemented endoprostheses]

In the presented paper the authors evaluate the long-term results of treatment for inflammatory and thromboembolic complications in knee joint alloplasty with cemented endoprostheses. The clinical material spanning the years 1998-2003 are 15 patients with analysed complications, it determine 9% of all operated. They have evaluated achieved results using the HSS knee rating scale in their own modification. As far as the authors are concerned, venographic examination is a prerequisite for appropriate care of the patients following knee joint alloplasty who might have deep venous thrombosis. It is necessary to provide similar treatment when developing infections are suspected in the perioperative period and in cases of late infections. Consequently, antibiotic therapy and a possible quick bacteriological checkup for healing a postoperative wound is a prerequisite for successful treatment. Achieved results induce statement, that thromboembolic and inflammatory complications caused at most operated chronic vein insufficiency, deficit of range of motion at operated joint and gait insufficiency. Thromboembolic complications was always related with inflammation of knee joint alloplasty in our own material.     

Factor Xa-activated whole blood clotting time (Xa-ACT) for bedside monitoring of dalteparin anticoagulation during haemodialysis.

BACKGROUND: Low molecular weight heparins (LMWH) like dalteparin are increasingly used for anticoagulation during haemodialysis (HD). The available laboratory tests for monitoring LMWH anticoagulation are time-consuming and expensive, and the suitability of the conventional activated clotting time (ACT) is controversial. A simple and cheap bedside test would be useful. METHODS: We studied the factor Xa-activated whole blood clotting time (Xa-ACT) in vitro and in vivo in nine patients undergoing chronic HD with i.v. dalteparin bolus anticoagulation and compared it with the conventional ACT. Plasma anti-factor Xa (antiXa) activity was determined with a chromogenic assay. Thrombin-antithrombin complexes were measured to detect coagulation activation. RESULTS: Xa-ACT and ACT were prolonged with rising dalteparin concentration. In vitro, both clotting times were strongly correlated with the antiXa levels (r = 0.94 and 0.89, respectively). Nevertheless, compared with the ACT, the Xa-ACT was considerably more sensitive to the LMWH in vitro (healthy blood: Xa-ACT 90 s/U vs ACT 26 s/U; uraemic blood: Xa-ACT 96 s/U vs ACT 31 s/U) as well as in vivo (Xa-ACT 81 s/U vs ACT 22 s/U) and reflected different intensities of anticoagulation. An initial dalteparin bolus of 80+/-11 U/kg body weight was able to prevent coagulation activation for up to 4 h of HD. CONCLUSION: For monitoring LMWH anticoagulation the Xa-ACT was superior to the conventional ACT in vitro as well as in vivo during HD. The Xa-ACT can be useful as a LMWH bedside test. The ACT was not sensitive enough to serve as a LMWH monitoring tool.     

Endoscopic transthoracic sympathectomy: current indications and techniques

Zusammenfassung GRUNDLAGEN: Die endoskopische thorakale Sympathektomie (ETS) existiert seit 60 Jahren als effektive Therapie der primären Hyperhidrose. Nach wie vor gibt es in der medizinischen Welt teils Vorbehalte, teils Unwissen über die Methode selbst, ihre Erfolgs- und Komplikationsraten sowie Nebenwirkungen. METHODIK: Nach Einführung in die Symptome und Behandlung der primären Hyperhidrose (konservativ und chirurgisch) werden Operationsmethoden und Langzeitergebnisse der ETS-Operation vorwiegend anhand der Daten aus der eigenen Abteilung präsentiert. ERGEBNISSE: Von 1965–2001 wurden 734 Sympathikotomien (ETS2–4) und bis 2003 weitere 103 Sympathikusblockaden (ESB4) bei Patienten mit primärer palmarer und axillärer Hyperhidrose durchgeführt. Die Konversionsrate betrug 0,1 %. Seit Einführung der Video-Thorakoskopie 1991 trat kein postoperatives Horner-Syndrom auf (zuvor 2,2 %), Drainage-pflichtige Pneumothoraces waren in 1,1 % zu verzeichnen. Nach einem medianen Follow-up von 16 Jahren waren 93 % der Extremitäten trocken, 5 % fast trocken und 2 % feucht. Nebenwirkungen traten in Form von kompensatorischem Schwitzen am Stamm (55 % insgesamt, davon 5 % stark) und gustatorischem Schwitzen (33 %) auf. Seit Einführung der limitierten Sympathikusblockade auf Höhe T4 (ESB4) konnte (bei naturgemäß kurzer Nachbeobachtungszeit) das kompensatorische Schwitzen auf 8,5 % und das gustatorische Schwitzen auf 2,1 % gesenkt werden. Mit dem postoperativen Ergebnis waren 100 % der Patienten nach ESB4 zufrieden, nach ETS2–4 waren 80 % zufrieden, 14 % teilweise zufrieden und 6 % unzufrieden (meist wegen starken kompensatorischen Schwitzens). SCHLUSSFOLGERUNGEN: Die ETS-Operation bietet hohe langfristige Erfolgsraten bei niedrigen Komplikationsraten. Patienten sollten über die zu erwartenden Nebenwirkungen genau aufgeklärt werden, für unzufriedene Patienten mit starkem kompensatorischem Schwitzen besteht nun die Möglichkeit der thorakoskopischen Klip-Entfernung.     

Medizinische Beurteilungskriterien zu bandscheibenbedingten Berufskrankheiten der Lendenwirbelsäule (II)

The first part of this serial paper dealt with the medical criteria used in evaluation of the clinical picture caused by physical stress and the evaluation of other candidate causes and was published in issue no. 3/2005 (pp. 711–752) of Trauma and Berufskrankheit. This follow-up paper (II) presents criteria to be used in the evaluation of whether it is necessary to give up the occupations putting the spine at risk and in estimation of the degree of disability.     

Proximaler Humerusnagel bei körpernahen Oberarmbrüchen

Zusammenfassung Frakturen des proximalen Humerus stellen beim älteren Patienten, bedingt durch Osteopenie und Verletzungsschwere, eine Herausforderung für die operative Versorgung dar. Seit wenigen Jahren stehen intramedulläre Implantate zur Verfügung, mit denen auch Mehrfragmentfrakturen mit hoher Primärstabilität versorgt werden können. Bei limitierten Weichteilschäden kann durch frühe Physiotherapie ein gutes funktionelles Ergebnis erreicht werden. Seit 2003 verwenden wir den T2-PHN (Fa. Stryker) und konnten bisher 15 Patienten nach 1-jähriger Beobachtung auswerten. Bei einem Durchschnittsalter von 64,6 Jahren lag der durchschnittliche Constant-Score nach 1 Jahr bei 68,3 (±17,3) auf der betroffenen Seite, seitenadaptiert wurden 79% erreicht. Der Anteil der 4-Segment-Frakturen lag bei 60%. Bei 4 Patienten beobachteten wir eine partielle Humeruskopfnekrose ohne Therapiekonsequenz. Implantatentfernungen waren in 5 Fällen wegen überstehender Schrauben oder vorstehendem proximalem Nagelende nötig. Mit den modernen Verriegelungsmarknägeln ist eine Gewebe schonende und sehr stabile Versorgung der proximalen Humerusfrakturen möglich.     

Pharmacotherapy of ventricular fibrillation. A prospective study in an emergency medical service

This prospective study investigated the effects of standard pharmacotherapy in out-of-hospital ventricular fibrillation (VF) after i.v. or endobronchial (e.b.) administration of epinephrine and lidocaine. METHODS. Only patients presenting with out-of-hospital VF were included in this study, whereby VF of noncardiac origin was excluded. Cardiopulmonary resuscitation (CPR) was performed according to the guidelines of the American Heart Association. Basic life support was initiated by Emergency Medical Service (EMS) technicians. The first step of advanced life support was immediate defibrillation by the EMS physician. Epinephrine was given in doses of 2.5 mg e.b. or 1.0 mg i.v. If indicated, patients received 200-500 mg lidocaine e.b. or 100 mg i.v. The course of CPR was tape-recorded and 2-3 blood samples were taken from each patient for drug monitoring. Plasma levels of epinephrine and lidocaine were measured by high-pressure liquid and gas chromatography, respectively, and then correlated to the course of CPR. RESULTS. Forty-seven patients presented VF on arrival of the EMS physician. Restoration of spontaneous circulation was achieved in 64% (Table 3), and 30% of the patients were discharged from hospital without major neurologic deficits. Immediate defibrillation before initiation of pharmacotherapy produced a success rate of 15.8%, whereas defibrillation after drug therapy was successful in 61.5% of cases. Following e.b. instillation of 2.5 mg epinephrine (Fig. 1), median peak concentrations of epinephrine (40.2, range 4.0-79.8 ng/ml) were reached after 3-4 min and plasma levels greater than or equal to 10 ng/ml were seen for 20 min. After i.v. injection of 1.0 mg epinephrine (Fig. 2) maximum concentrations (71.6, range 4.7-104.2 ng/ml) were measured after 1-2 min and plasma levels decreased below 10 ng/ml after 10 min. Following e.b. instillation of 400-500 mg lidocaine mean lidocaine concentrations within the therapeutic range (2-5 micrograms/ml) were reached after 4-5 min and remained within these limits for 20-30 min. Peak concentrations were obtained after 12 min. Doses of 200-320 mg lidocaine e.b. failed to achieve therapeutic plasma levels (Fig. 3). Regarding the pharmacodynamic aspects of drug therapy, 22.5% of the initial survivors were resuscitated from VF without therapeutic epinephrine, presenting with mean endogenous epinephrine concentrations of 7.1 ng/ml, 51.6% of patients were resuscitated after epinephrine therapy with plasma concentrations greater than 20 ng/ml. In only 1 case could a relationship be demonstrated between the administration of lidocaine and resuscitation success. CONCLUSION. In CPR, the e.b. administration of epinephrine and lidocaine is a reliable alternative to the i.v. injection route of these drugs. Recommended doses are 2.5 mg for epinephrine and 400-500 mg for lidocaine. Resuscitation from VF requires immediate epinephrine therapy if initial defibrillation is not successful. Lidocaine has no effect on resuscitation from VF and therefore should be used specifically for antiarrhythmic therapy after restoration of spontaneous circulation.     

123I-amphetamine-SPECT in classical migraine and migraine accompagnée

Migraine is considered to be a functional neurological disorder. In classical migraine (headache associated with prodromal visual field disturbances) and migraine accompagnée (headache associated with transient neurological symptoms), disturbances of cerebral blood flow and amine metabolism are thought to be pathogenetic factors. However, conventional methods of neuroimaging (CAT, NMR) usually do not yield any pathological findings in patients. Since 123I-iodoamphetamine (123I-IMP) crosses the intact blood brain barrier, 123I-IMP-SPECT is used for the assessment of cerebral perfusion in various neurological diseases, including functional disorders. 123I-IMP-SPECT was performed on 5 patients with classical migraine and 18 patients with migraine accompagnée. At the time of investigation, all patients were symptom-free. Cerebral blood flow was decreased in all patients with migraine accompagnée, and often corresponded to the site of headache as well as to the topography of transient neurological symptoms. This reduction was most obvious in a patient with persisting neurological symptoms. Most patients with classical migraine, however, did not show any alteration of cerebral perfusion. It appears that migraine--and in particular migraine accompagnée--is characterized by a permanent alteration not only of cerebral blood flow but also of neuronal activity. Migraine attacks may occur in connection with exacerbations of preexisting metabolic alterations.     

Characterisation of surface-modified solid lipid nanoparticles (SLN): influence of lecithin and nonionic emulsifier.

Solid lipid nanoparticles (SLN), an alternative colloidal drug delivery system to polymer nanoparticles, emulsions and liposomes, are generally produced by high pressure melt-emulsification. However, the harsh production process is not applicable for formulations containing shear and temperature sensitive compounds. For that reason, subsequent adsorptive SLN loading might be a promising alternative. The aim of the present study was the development and characterisation of surface-modified SLN for adsorptive protein loading by variation of both the lipid matrix and the emulsifier concentration in the continuous phase. Variations in SLN composition resulted in particle sizes between 674 and 61 nm corresponding to specific surfaces of 4.5 m(2)/g and 48.9 m(2)/g and zeta potentials between -23.4 mV and -0.9 mV. In dependence of SLN surface properties, albumin payload ranged from 2.5 to 15%. Thermoanalysis, X-ray diffraction and electron microscopy revealed anisometrical and crystalline particles. In vitro cytotoxicity was low in terms of both haemolysis, which was between 1 and 2%, and neutral red test (NRT) showing a half lethal dose between 1.1 and 4.6%.     

Anatomical Course of the Superficial Branch of the Radial Nerve and Clinical Significance for Surgical Approaches in the Distal Forearm

Abstract 10 embalmed cadaver forearms and wrists were dissected to determine the anatomical course of the superficial branch of the radial nerve in the distal forearm. The superficial radial nerve bifurcated in two branches at a mean of 54,7 mm proximal to the radial styloid. From the styloid process of the radius, the mean distance to the closest dorsal branch of the superficial radial nerve was 3,5 mm and the mean distance to the closest volar branch was 9,8 mm. The mean distance between the closest branch of the superficial radial nerve and Lister?s tubercle was 16,4 mm. The crossing point between the nerve and the cephalic vein was located at a mean of 54,3 mm proximal to the styloid process. At the level of styloid process the mean distance between the closest dorsal branch of the superficial radial nerve and the first dorsal compartment was 15,2 mm and between the closest volar branch and the first dorsal compartment 4,4 mm. Detailed knowledge of anatomic characteristics of the superficial branch of the radial nerve may help prevent injury during operations and treat traumatic lesions of the nerve. Because of great variations in the course of the superficial radial nerve we could not define an absolute safe zone for surgical procedures on the distal forearm. Iatrogenic lesions of the superficial radial nerve are described complications of percutaneous procedures. Therefore open surgical approaches are recommended. Daniela Klitscher and Lars Peter Müller contributed equally to this work.