Biomedical subjects
Publications and source records attributed to A Schultz.
We report on the case of a 9-year-old girl who presented vaginal bleeding which led to the diagnosis of vaginal hemangioma. Such localisation is rare, and requires a clinical follow-up by vaginoscopy. A spontaneous regression can be expected but, at this time, the progress of puberty and future fertility are unknown.
PURPOSE: Fundoplication has been used successfully to treat gastroesophageal reflux (GER) in the pediatric population. Although successful in many patients, there is a significant risk of complications and failure, especially in high-risk patients such as those with certain types of associated anomalies, diffuse motility disorders, chronic pulmonary disease, neurological impairment, and young infants. However, the results are poorer with children with severe pathologic lesion associated to reflux: tracheoesophageal cleft, esophagocoloplasty, and esophageal atresia (EA) with severe dysmotricity. In neurologically impaired children with neuromuscular incoordination and GER, Bianchi has proposed total esophagogastric dissociation (TED). The authors report the use of esophagogastric or esocologastric dissociation to control reflux in children with severe GER in other situations, such as EA, burn esophageal lesions having led to coloplasty and severe esotracheal cleft. METHODS: The authors reviewed the patients operated on for an esogastric or cologastric disconnection between 1997 and 2002. It is a single center retrospective study. The initial diagnosis, previous surgical procedure, postoperative course, and follow-up results were studied. RESULTS: Between September 1999 and June 2003, 13 TEDs were performed in 6 boys and 7 girls. The mean age for TED procedure was 35 months (range 14 days to 218 months). Indication for TED was severe persistent reflux in, respectively, 9 cases of EA (7 with coloplasty and 2 with preservation of the native esophagus after atresia repair, associated in 1 case with an esotracheal cleft), 2 cases of esotracheal cleft type III, and 2 cases of esophagocoloplasty for caustic burns. Six patients had undergone previous fundoplications (1-4 procedures) that failed, whereas the remaining patients underwent TED as the primary antireflux procedure. The average follow-up was 26 months (range 1 month to 4 years). There were no complication during the immediate postoperative course. Three children died at 3, 4, and 12 months after the procedure from acute respiratory failure. Respiratory status was improved in 8 children, and recurrent bronchitis was noted in 1 child. Regarding the digestive status, gastrostomy was closed at 18 and 24 months in 2 children, and partial nocturnal enteral nutrition (200 to 900 mL/d) through the gastrostomy remains necessary in the other children. CONCLUSION: Total esophagogastric dissociation procedure improves the respiratory consequences of severe GER, particularly in children for whom other surgical treatments have failed. The long-term safety of this operation remains to be determined especially regarding the consequences of a gastrointestinal Roux-en-Y loop procedure.
BACKGROUND: Impaired baroreflex sensitivity (BRS) is a negative predictive factor of mortality in cardiovascular disease. Aldosterone has been shown to decrease BRS in humans and animal models. However, the mode of aldosterone action, whether genomic or nongenomic has not been determined. Therefore, we conducted a clinical study to examine whether BRS, as measured by the phenylephrine method, is impaired in humans by aldosterone by a nongenomic mechanism. METHODS: In a randomised, double-blinded, fourfold cross-over trial in 16 healthy male volunteers, BRS was tested 15 minutes after initiation of a continuous infusion of aldosterone (3 microg/minute) or placebo. 6 hours earlier, this period was preceded by an injection of either canrenoate (400 mg) or placebo. RESULTS: BRS was 34.6 +/- 4.7 ms/mm Hg in the placebo/placebo period. It was significantly blunted in the placebo/aldosterone (25.5 +/- 1.8 ms/mm Hg) as well as in the canrenoate/placebo (24.0 +/- 1.5 ms/mm Hg) and the canrenoate/aldosterone (25.4 +/- 2.5 ms/mm Hg) periods. CONCLUSION: These data suggest that the decreased BRS caused by aldosterone is due to a rapid, thus presumably nongenomic mechanism, as these effects occur in a time frame that excludes genomic aldosterone effects at large. The mineralocorticoid receptor (MR) antagonist canrenoate does not block these effects, but blunts BRS by itself.
Previous investigations revealed that ABO blood groups are associated with divergent concentrations of several coagulation factors. Concentrations of von Willebrand factor (vWF) and factor VIII are lower in individuals with blood group O as compared to subjects with blood group A, B or AB which might result in a reduced inhibition of platelet aggregation. The aim of the present in-vitro-investigation was to elucidate the impact of ABO blood group dependent vWF concentrations on tirofiban mediated inhibition of GPIIb/IIIa function. Platelet function was measured with the platelet function analyzer PFA-100 at baseline and at increasing concentrations of tirofiban and stratified for blood group O vs. A. If measured with the collagen/epinephrine cartridge, blood group O was associated with a prolonged mean baseline closure time in comparison with blood group A (175.8 +/- 64.9 s vs. 121.4 +/- 33.4 s, p = 0.037) which was paralleled by reduced concentrations of vWF and factor VIII. In contrast, no differences in closure time (227.6 +/- 76.1 s vs. 223.9 +/- 81.9 s, p = 0.96) could be found in the presence of tirofiban (0.1 microg/ml). Thus, tirofiban mediated GP IIb/IIIa receptor antagonism as determined with the PFA-100 seems to be independent on plasma concentration of vWF.
Elderly patients are significantly less likely to receive statins than younger patients possibly because of doubts regarding compliance or concerns regarding the increased likelihood of adverse events and drug interactions. Poor compliance can be expected especially in patients suffering from dementia or depression as well as those whose stage of cardiovascular disease exhibits few symptoms. On the other hand, the clinical significance of CHD events is high in the elderly, and 80% of coronary deaths occur in patients aged over 65 years. The average statistical life expectancy of elderly and old patients is often underestimated. The HPS and PROSPER studies showed that statins reduce mortality and morbidity even in very elderly individuals with a high global cardiovascular risk and/or CAD. Patients up to the age of 79 years should be treated according to the same guidelines as younger patients. Statin therapy should only be considered for patients aged 80 years and older who are at a very high risk for cardiovascular events.
BACKGROUND: Glucocorticosteroids are effective in the treatment of allergic rhinitis, a disease characterized by a variety of symptoms, e.g. rhinorrhea and itching. The time course of symptomatic relief for allergic rhinitis by steroids has not been examined in detail to date, although the onset of steroid action is one of the main discriminations between genomic and nongenomic actions of steroids. We therefore investigated the time course of subjective and objective measures of nasal affection after steroid administration in patients with allergic rhinitis following specific allergen challenge. METHODS: Six female and 18 male volunteers (median age 26 years) with a history of allergic rhinitis but currently free of symptoms were included in this randomized, placebo-controlled, double-blind, three-period crossover study. A single dose of either betamethasone (60 mg), methylprednisolone (400 mg) or placebo was given intravenously, 5 min after intranasal allergen provocation. After 10, 20, 60, 150 and 240 min, nasal itching and nasal obstruction were assessed using a standardized visual analogue scale. In addition, nasal airflow was measured by anterior rhinomanometry. RESULTS: Nasal itching was markedly reduced following either of the two steroids within 10 min after administration of study drug. Itching was depressed by 38% following betamethasone (P<0.05) and by 18% following methylprednisolone (P=0.07) compared with placebo. Nasal airflow and nasal obstruction were not significantly altered by steroids during the first 2 h of the study. However, after 150 min, nasal airflow was 21% rsp. 19% higher after methylprednisolone and betamethasone (P<0.05) compared with placebo. After 240 min, nasal airflow was increased by 20% following betamethasone (P<0.05) and by 19% following methylprednisolone. Nasal obstruction was also beneficially affected by both steroids 150 and 240 min after administration compared with placebo (P<0.05 for both time points following betamethasone). CONCLUSION: This study for the first time shows rapid in vivo effects of external glucocorticosteroids in humans. Itching, a pathophysiologically complex sensation, is favourably influenced by steroids within 10 min, therefore presumably via nongenomic mechanisms. Though no detailed mechanisms can be derived from this study, steroid interaction with receptors in the central nervous system may play an important role in mediating this effect.
BACKGROUND: Age-related differences in the spectral composition of the EEG in induction and emergence times, and in drug consumption during propofol anaesthesia were investigated. METHODS: The EEGs of 60 female patients between 22 and 85 years of age were monitored continuously during standardized induction of anaesthesia with 2 mg of propofol kg(-1)60 s(-1). The EEGs were visually assessed in 20-s epochs according to a scale from A (awake) to F (very deep hypnosis). Visual EEG classifications, spectral parameters, and induction times were compared between different age groups. Additionally, data of 546 patients included in a multicentre study with 4630 patients (EEG monitor Narcotrend, MT MonitorTechnik, Bad Bramstedt, Germany) were analyzed with regard to age-dependent changes of propofol consumption using target-controlled infusion (TCI). RESULTS: During induction, patients older than 70 years reached significantly deeper EEG stages than younger patients, needed a longer time to reach the deepest EEG stage, and needed more time until a light EEG stage was regained. In patients aged 70 years and older, the total power, mainly in deep EEG stages, was significantly smaller due to a distinctly smaller absolute power of the delta frequency band. No single spectral parameter was able to reliably distinguish all EEG stages. During the steady state of anaesthesia, older patients needed less propofol for the maintenance of a defined stage of hypnosis than younger patients. CONCLUSION: Older patients differ from younger ones regarding the hypnotic effect of propofol and the spectral patterns in the EEG. For an efficient automatic assessment of the EEG during anaesthesia a multivariable approach accounting for age-effects is indispensable.
A reliable assessment of the depth of hypnosis during sedation and general anaesthesia using the EEG is a subject of current interest. The Narcotrend Index implemented in the latest version 4.0 of the EEG monitor Narcotrend provides an automatic classification of the EEG on a scale ranging from 100 (awake) to 0 (very deep hypnosis, EEG suppression). The classification algorithms implemented in the EEG monitor Narcotrend are described. In a study the correlation of the propofol effect-site concentration with the Narcotrend Index and with the traditional spectral parameters total power, relative power in the standard frequency bands delta, theta, alpha, and beta, median frequency, 95% spectral edge frequency, burst-compensated spectral edge frequency, and spectral entropy was investigated. The Narcotrend Index had the highest average correlation with the propofol effect-site concentration and the smallest variability of the individual correlation values. Moreover, the Narcotrend Index was the only parameter which showed a monophasic trend over the whole investigated time period. The Narcotrend monitor can make a significant contribution to the improvement of the quality of anaesthesia by adjusting the dosage of hypnotics to individual patient needs.
The Narcotrend performs an automatic interpretation of the electroencephalogram (EEG) during anaesthesia. The classification algorithms have been developed on the basis of visually classified EEG epochs. The classification scheme which was used for these visual assessments has its origin in sleep analysis and was adapted for the EEG during anaesthesia. From the awake state to very deep anaesthesia, 15 stages (A, B(0-2), C(0-2), D(0-2), E(0-2), F(0-1)) are distinguished. The transformation of these stages into a numerical scale from 100 to 0 is a further refinement for a differentiated presentation of EEG effects. For the automatic classification multivariate discriminant functions are used. Age-related changes of the EEG were incorporated. The device contains functions for the identification of artifacts. The EEG can be recorded from a frontal channel using standard ECG electrodes, other electrode positions and types can be chosen. The device has been clinically and scientifically validated.
This study investigates apoptotic effects of protein kinase C (PKC) delta and theta in neuroblastoma cells. 12-O-tetradecanoylphorbol-13-acetate induces apoptosis in SK-N-BE(2) neuroblastoma cells overexpressing PKCdelta or PKCtheta, but not PKC epsilon. The PKC inhibitor GF109203X does not suppress this apoptotic effect, suggesting that it is independent of the catalytic activity of PKC. The isolated catalytic domains of PKCdelta and PKCtheta or the regulatory domain (RD) of PKCtheta also induce apoptosis in neuroblastoma cells. The apoptotic responses are suppressed by caspase inhibition and by Bcl-2 overexpression. The PKCtheta RD induced apoptosis also in Jurkat cells. Colocalisation analysis revealed that the PKCtheta RD primarily localises to the Golgi complex. The C1b domain is required for this localisation and removal of the C1b domain results in a PKCtheta construct that does not induce apoptosis. This suggests that the PKCtheta RD has apoptotic activity and that Golgi localisation may be important for this effect.
BACKGROUND: Cochlear implantation is a widely used means of treating deafness and severe hearing disorders. The surgical procedure includes inserting the cochlear implant electrode array into the cochlea and embedding the corresponding signal receiver in the mastoid bone behind the ear. Postoperative fitting of the externally worn speech processor is very important for successful use of the cochlear implant. For this purpose, electrically elicited stapedius reflex threshold values can be used. However, stapedius reflex threshold values measured intraoperatively are influenced by anaesthetics. The goal of this retrospective study was to find out whether electroencephalogram (EEG) control of anaesthesia produces more reliable reflex threshold values as a basis for the fitting of the speech processor. METHODS: Three groups of children, after surgery for cochlear implantation, were analysed with regard to the magnitude of intraoperative electrically elicited stapedius reflex threshold values and their deviations from postoperatively determined maximum comfortable levels (group 1: methohexital/remifentanil with EEG monitoring, n = 10; group 2: isoflurane/fentanyl with EEG monitoring, n = 9; group 3: isoflurane/fentanyl without EEG monitoring, n = 11). RESULTS: Children with EEG monitoring had significantly lower electrically elicited stapedius reflex threshold values and also significantly lower differences between intraoperative stapedius reflex threshold values and postoperatively determined maximum comfortable levels. CONCLUSIONS: Electroencephalogram monitoring in cochlear implantation is of considerable value in controlling anaesthesia and improving speech processor fitting based on more reliable intraoperative neurophysiological data.
Steroid hormones may profoundly influence hemostasis; for example, as discussed for hormone replacement therapy, pregnancy and, being less obvious, for the ovarian cycle. We investigated primary hemostasis parameters using a platelet function analyzer (PFA-100) during the follicular and luteal phases in 18 healthy young women without oral contraceptives. During the follicular phase, the mean closure time (CT) was 164.7 +/- 56.7 s, and it decreased to 130.2 +/- 30.6 s in collagen/epinephrine cartridges in the luteal phase (P = 0.0095). No significant difference could be found for CT values in collagen/adenosine diphosphate cartridges during the follicular phase as compared with the luteal phase (97.2 +/- 24.2 s versus 89.6 +/- 18.4 s, P = 0.174). Negative correlations between the CT values in collagen/epinephrine cartridges and von Willebrand factor from both phases of the cycle were found (follicular phase: r = -0.53; luteal phase: r = -0.54). Fibrinogen and fibrinogen degradation products were significantly increased in the luteal phase (2.49 +/- 0.62 g/l versus 2.05 +/- 0.59 g/l and 0.12 +/- 014 versus 0.04 +/- 0.04, P = 0.02 for both parameters) as compared with the follicular phase. No significant differences could be detected for plasminogen, plasmin-antiplasmin complex, prothrombin fragment 1 + 2 and D-dimer between the groups. This study indicates that platelet function is periodically altered during the ovarian cycle due to the influence of progesterone and estrogen on von Willebrand factor concentrations.
Previous studies have revealed beneficial in vitro effects of progesterone on sperm function. The aim of this pilot study was to prove if orally given micronized progesterone leads to elevations in progesterone and/or 17alpha-hydroxyprogesterone levels in seminal plasma, since higher seminal plasma levels of these hormones could possibly have a beneficial effect on sperm function as seen in in vitro investigations. Multiple application of micronized progesterone given over 4 days (daily dose 400 mg) to 6 healthy subjects resulted in elevated seminal plasma levels of progesterone (10.90 +/- 9.02 nmol/l vs. 1.43 +/- 0.56 nmol/l, p = 0.04) and 17alpha-hydroxyprogesterone (3.09 +/- 1.72 nmol/l vs. 1.62 +/- 1.26 nmol/l, p = 0.04) whereas no significant difference could be found in testosterone levels (34.82 +/- 13.00 vs. 30.91 +/- 8.56 nmol/l, p = 0.43). In contrast, androstendione levels in seminal plasma were reduced (2.68 1.28 nmol/l vs. 3.65 +/- 1.36 nmol/l, p = 0.01). Although micronized progesterone is rapidly metabolized, oral application resulted in pronounced elevations of progesterone and 17alpha-hydroxyprogesterone in seminal plasma. Further studies will show if oral application of micronized progesterone can induce beneficial effects on sperm function such as those seen in in vitro investigations.
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Peptide sequencing by surface-induced dissociation (SID) on a MALDI-ion mobility-orthogonal TOF mass spectrometer is demonstrated. SID of approximately 100-fmol amounts of model peptides HLGLAR (m/z 666.8), gramicidin S (m/z 1142.5), and bovine insulin b chain (m/z 3495.5) was accomplished using hydrocarbon-coated gold grids and approximately 20-eV collision energies. The current version of the instrument achieves a mobility resolution of approximately 20 and TOF mass resolution better than 200. Peptide sequences of four peptides from a tryptic digest of cytochrome c (approximately 1 pmol deposited) were obtained. The advantage of IM-SID-o-TOF-MS is that a single experiment can be used to simultaneously measure the molecular weights of the tryptic peptide fragments (e.g., peptide mass mapping) and partial sequence analysis, (e.g., real-time tandem mass spectrometry.)
In a 62-year-old female patient without a history of epileptic seizures EEG monitoring (EEG monitor: Narcotrend) was routinely performed during propofol/remifentanil and during sevoflurane/remifentanil/nitrous oxide anaesthesia. In the first course of anaesthesia after a bolus of propofol 1% a continuous EEG slowing was followed by a burst suppression pattern without occurrence of epileptiform activity throughout this sequence. During the second course of anaesthesia the sevoflurane concentration was increased from 2 to 8 % by volume. After 5 min epileptiform activity appeared in the EEG at an endtidal concentration of 5.9% by volume.
OBJECTIVE: In this article unexpected EEG findings are described which were observed during EEG monitoring under sevoflurane anesthesia. METHOD: In seven non-epileptic adult patients sevoflurane was administered as inhalation anesthetic during routinely performed surgical operations. The EEG was recorded continuously as part of the standard monitoring process and served mainly as a dosage guide for anesthetics/narcotics. MAIN OUTCOME MEASURE: Occurrence of sharp transients in the EEG resembling distinctive waves which can be seen in epileptic disorders. RESULTS: In six of the seven patients under 8.0% sevoflurane, sharp transients were observed which appeared in very deep EEG stages, mostly with endtidal sevoflurane concentrations of 4.8-5.9%. The findings are in accordance with observations in non-epileptic children from our clinic. CONCLUSIONS: The clinical significance of the observed EEG pattern under sevoflurane anesthesia is still unclear. Taking into consideration that convulsive and nonconvulsive status epilepticus can be followed by signs of brain damage, it would appear to be important to further investigate the phenomenon.
EEG monitoring can be performed at the patients' bedside and it is a valuable support in therapeutic decision making providing unique information about the functional state of the brain. Due to newer technical developments, EEG monitoring can be conducted rather easily. In this article, indications for EEG monitoring in plastic surgical patients are presented: controlling the level of sedation, use in states of increased intracranial pressure, screening the cerebral state in comatose patients, diagnosis and therapy of epileptic seizures, and the search for circumscribed cerebral abnormalities. Furthermore, practical experience with the use of the new EEG monitor Narcotrend, which is provided with an automatic EEG classification, is described.