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B Eberle

Publications and source records attributed to B Eberle.

At least 73 records · Page 4Linked to original sources
PubMed1995

Isolation, characterization and RFLP linkage mapping of a DNA repeat family of Solanum spegazzinii by which chromosome ends can be localized on the genetic map of potato.

In a random sample of 2263 cloned genomic DNA fragments of the wild potato species Solanum spegazzinii six related, highly repetitive fragments (SPG repeat family) were identified that were present in much higher copy numbers in S. spegazzinii when compared with the closely related cultivated potato S. tuberosum. The SPG repeat family was organized in long arrays of multiple copies. Cross hybridization experiments with 29 wild and cultivated Solanum species and with the related tomato showed specificity of the SPG repeat family for tuber-bearing Solanum species. Among tuber bearing Solanum species a high degree of variation was observed for restriction fragment length and copy number. The variation in copy number was not correlated with established taxonomic relationships between tuber-bearing Solanum species. DNA sequence analysis revealed a subrepeat structure of 120-140 base pairs embedded in longer repeat units of variable length. Length polymorphisms between highly repeated restriction fragments detected by the SPG probes were used for segregation- and linkage analysis in four mapping populations of potato, for which RFLP maps had been constructed. Twelve loci were identified, eleven of which mapped to the distal ends of nine linkage groups. All the evidence suggested that the SPG repeat family represents a satellite repeat members of which are localized in the subtelomeric region of potato chromosomes. The SPG repeat family could be used, therefore, for completing the genetic map of potato.

Base Sequence↗
PubMed1994

Differences in the topographical distribution of EEG activity during surgical anaesthesia and on emergence from volatile anesthetics.

Computerized processing of a 16 channel EEG allows mapping and display of cortical electrical activity in a useful mode for intraoperative monitoring. We studied the topographical distribution of EEG-activity displayed as spectral maps comparing inhalational anaesthesia with isoflurane or enflurane during surgical anaesthesia and emergence. Two groups of nine patients each were anaesthetized with one of the two regimens. The EEG patterns during steady state end-tidal concentrations of isoflurane (0.7-1.1%) or enflurane (0.8-1.3%) showed highest activity in the frontal and occipital areas. At near awakening the frontal and occipital dominance of delta activity disappeared in both groups and was replaced by homogeneous delta activity over the entire cortex; variations in the topographical distribution of enflurane and isoflurane were recorded in the other spectral bands. We conclude that changes in topographic EEG patterns observed during the transition from surgical anaesthesia to emergence, in particular the disappearance of frontal and occipital dominance of delta activity common to isoflurane and enflurane, may serve to detect undesirably light levels of anaesthesia.

Adult↗
PubMed1994

Quality of on-site performance in prehospital advanced cardiac life support (ACLS).

UNLABELLED: The aim of our prospective study was to assess the structural and procedural quality of an urban emergency medical services (EMS) system providing prehospital basic and advanced cardiac life support (BLS/ACLS), to compare the onsite performance of physicians and non-physicians in ECG diagnosis and defibrillation, and to identify incidence and causes of avoidable delays in the initial treatment sequences. METHODS: Between 1 February 1991 and 1 July 1992, 162 on-line tape recordings of prehospital cardiopulmonary resuscitation (CPR) efforts performed by the staff of the EMS system of the city of Mainz were evaluated. After arrival at the patient's side, time intervals to initial ACLS steps (first ECG-diagnosis, first defibrillation, endotracheal intubation, first epinephrine administration) were measured. Times to rhythm identification and countershock by EMT-Ds vs. physicians were compared (Mann-Whitney U-test). Time intervals are presented as median values. One-hundred sixty-two adult patients with out-of-hospital cardiac arrests (ventricular fibrillation [VF] or ventricular tachycardia [VT], 72; asystole or electromechanical dissociation [EMD], 90) receiving CPR by EMTs, EMT-Ds, and physicians of the Mainz EMS were included. Patients with arrests due to non-cardiac aetiologies were excluded. RESULTS: After arrival at the patient's side, for patients with VF/VT, the EMT-Ds took 1:36 min and the physicians took 1:00 min to obtain the first ECG diagnosis (P = 0.004). The first countershock was delivered within 1:42 min by both EMT-Ds and physicians of the mobile intensive care unit (MICU). After diagnosis was established, the EMT-Ds took 0:08 min to defibrillate, whereas the physicians took 0:36 min (P = 0.0001).(ABSTRACT TRUNCATED AT 250 WORDS)

Cardiopulmonary Resuscitation↗
PubMed1994

Reduced blood-brain barrier permeability after cardiac arrest by conjugated superoxide dismutase and catalase in piglets.

BACKGROUND AND PURPOSE: Cardiac arrest and resuscitation in immature piglets result in a delayed increase in blood-brain barrier permeability. We tested the hypothesis that pretreatment with oxygen radical scavengers reduces postischemic permeability. METHODS: Permeability was assessed by measuring the plasma-to-brain transfer coefficient of the small amino acid, alpha-aminoisobutyric acid, in 2- to 3-week-old anesthetized piglets. Three groups were studied: (1) a nonischemic time control group (n = 5), (2) an ischemia group (n = 8) pretreated with 5 mL of polyethylene glycol vehicle, and (3) an ischemia group (n = 8) pretreated with polyethylene glycol conjugated to superoxide dismutase (10,000 U/kg) and to catalase (20,000 U/kg). The ischemia protocol consisted of 8 minutes of ventricular fibrillation, 6 minutes of cardiopulmonary resuscitation, defibrillation, and 4 hours of spontaneous circulation. RESULTS: The mean +/- SEM of the transfer coefficient of alpha-aminoisobutyric acid in cerebrum was (in microL/g per minute): 1.54 +/- 0.37 in the nonischemic group, 2.04 +/- 0.26 in the ischemia group treated with vehicle, and 1.29 +/- 0.25 in the ischemia group treated with oxygen radical scavengers. Postischemic values with scavenger treatment were significantly lower than those with vehicle treatment in cerebrum, cerebellum, medulla and cervical spinal cord. CONCLUSIONS: Pretreatment with oxygen radical scavengers reduces postischemic blood-brain barrier permeability by a small amino acid. These data are consistent with oxygen radical-mediated dysfunction of cerebral endothelium in a pediatric model of cardiopulmonary resuscitation.

Aminoisobutyric Acids↗
PubMed1994

Effect of vest cardiopulmonary resuscitation on cerebral and coronary perfusion in an infant porcine model.

OBJECTIVES: To determine cerebral and myocardial blood flow rates during vest cardiopulmonary resuscitation (CPR) without direct cardiac compression in an infant porcine model. Also, to determine if circumferential chest compression without the chest deformity ordinarily associated with precordial compression maintains cerebral and myocardial blood flow rates during prolonged CPR. Finally, to establish the effect of compression rate and duty cycle on cerebral and myocardial blood flow rates during vest CPR in this model. DESIGN: Prospective, randomized comparison of two compression rates and two duty cycles in four groups during prolonged CPR. SETTING: University cerebral resuscitation laboratory. SUBJECTS: Thirty-two infant domestic swine. INTERVENTIONS: Microsphere-determined cerebral and myocardial blood flow rates, perfusion pressures, and chest dimensions, were measured before and during prolonged vest CPR. Immediately after ventricular fibrillation, epinephrine administration was started and thoracic vest CPR was performed using a single combination of compression rates of 100 or 150/min and duty cycles of 30% or 60%. Measurements were made before and at 5, 10, 20, 35, and 50 mins of CPR. MEASUREMENTS AND MAIN RESULTS: Five minutes into CPR, between-group comparisons showed that cerebral blood flow was 16 to 20 mL/min/100 g and myocardial blood flow was 34 to 45 mL/min/100 g (48% to 62% and 25% to 33% of prearrest values). When CPR was prolonged, cerebral blood flow deteriorated similarly in all groups. Myocardial blood flow decreased over time but was better maintained in the groups with a 30% duty cycle (24 vs. 4 mL/min/100 g; p < .006). There were no differences between the two compression rates. Chest deformity after cessation of 50 mins of compression was < 3%. CONCLUSIONS: Cerebral and myocardial blood flow rates produced by vest CPR are comparable with rates reported using other types of CPR in this model. Deterioration in blood flow during prolonged CPR occurs despite a lack of chest deformation. The deterioration in myocardial blood flow during prolonged CPR is greater when a long duty cycle is used in this model.

Analysis of Variance↗
PubMed1993

Purification of selenoprotein Ph from human plasma.

There are three selenium-containing proteins in human plasma: glutathione peroxidase (GSH-Px-P), albumin and selenoprotein Ph, the human analogue to selenoprotein P from rat plasma. Selenoprotein Ph was separated from the two other selenium-containing proteins by Heparin Sepharose chromatography and was shown to have about 60-70% of the total plasma selenium, while both GSH-Px-P and albumin contain about 15%. A 2588-fold purification from human plasma was achieved by using a four-step procedure. SDS-PAGE of the purified selenoprotein revealed, besides one contaminant selenium-free protein band at about 70 kDa, one selenium-containing band ranging from 54 to 67 kDa with a maximum at 63 kDa. This microheterogeneity, also recognized by IEF, may be due to the glycprotein nature of the selenoprotein Ph. The determination of the molecular mass of the native protein varied from 65 kDa using gel filtration on Fraktogel HW 55 to 89 kDa on Sephacryl S-200 HR, suggesting an interaction between the gel-matrices and selenoprotein Ph.

Blood Proteins↗
PubMed1992

[The effect of muscle relaxants on masseter tone. An experimental study in an MH-susceptible swine model].

Malignant hyperthermia (MH) may occur, when a genetically predisposed individual or pig (MHS) is exposed to triggering agents. The increase in free, ionized sarcoplasmic calcium inducing the vicious circle of MH is believed to result from calcium-induced release with volatile anaesthetics, and from depolarization-induced calcium release with succinylcholine (SCH). The administration of SCH to susceptible humans or pigs frequently produces an increase in masticatory muscle tone. This hitherto ill-defined phenomenon is referred to as "masseter spasm" (MS). We have attempted to elucidate the pathophysiology of MS in a porcine model. METHODS. After the protocol had been approved by the state authorities, 6 MHS pigs were investigated. The pigs were mixed breeds (German Landrace and Dutch Pietrain) and were 9 +/- 1 weeks old with an average body weight of 25.5 kg. Premedication consisted of intramuscular injection of azaperone, 7.5 mg.kg-1. Anaesthesia was induced with piritramide, 1.2 mg.kg-1, administered via a cannulated ear vein. Subsequent to laryngoscopic endotracheal intubation, neuromuscular blockade was achieved with 4 mg pancuronium. Ventilation was set at 12 breaths per minute and adjusted to maintain an end-tidal CO2 concentration of 4.7% by adapting the tidal volume (PhysioFlex). Anaesthesia was maintained with piritramide, 2.25 mg.kg-1.h-1, pancuronium, 0.4 mg.kg-1.h-1, and N2O (60% in O2). Instrumentation included an arterial line, a central venous line, and a fiberoptic pulmonary artery catheter (Oximetrix). Masticatory muscle tone (MMT) was assessed with an intermolar balloon, connected to a pressure transducer and calibrated to zero prior to SCH administration. As a reference variable for effects produced by SCH, intraocular pressure (IOP) was measured manometrically in the anterior chamber. After stabilization of haemodynamic variables, the neuromuscular blockade was allowed to wear off. After recovery of the evoked masseter electromyogram, a paralyzing dose of pancuronium was administered (0.5 mg.kg-1). When paralysis was complete, SCH was administered (1.5 mg.kg-1), followed a few minutes later by dantrolene infusion (5 mg.kg-1 over 10 min). RESULTS. The administration of SCH was followed by clinically unequivocal MH episodes in all pigs, indicated by an increase in oxygen uptake (VO2; PhysioFlex; Fig. 1) and end-tidal CO2 concentration and a decrease in oxygen saturation of mixed venous blood (svO2; Fig. 2). Despite complete neuromuscular blockade (monitored with EMG), SCH produced an increase in MMT in all pigs which was reversed by dantrolene (Fig. 3). The time course of MMT paralleled that of IOP, suggesting a similar underlying mechanism. DISCUSSION. Succinylcholine is a trigger of MH in susceptible individuals; onset of the syndrome may be associated with "masseter spasm". SCH increases extraocular muscle tone, probably by means of stimulating multiply innervated fibers; the resulting IOP increase is not prevented by competitive neuromuscular blockade. The existence of multiple innervated fibers has also been shown in muscle spindles in the deep layers of the masseter, with their stimulation resulting in elevation of the jaw. We speculate that the increases in MMT and IOP observed in this study reflect the same process, i.e. a motor response, initiated by SCH-induced stimulation of the intramyocellular contractile system of multiply innervated muscle fibers, that is independent of neuromuscular transmission. Triggering of MH with SCH despite complete neuromuscular blockage suggests a mechanism other than depolarization-induced calcium increase. And, for the semantics, according to neurological terminology MS should be referred to as contracture not as spasm.

Anesthesia, Inhalation↗
PubMed1991

Blood-brain barrier disruption after cardiopulmonary resuscitation in immature swine.

We investigated blood-brain barrier permeability in 2-3-week-old anesthetized pigs during and after cardiopulmonary resuscitation. We assessed permeability by tissue uptake of radiolabeled aminoisobutyric acid, after correcting for plasma counts in tissue with radiolabeled inulin. Among 14 regions examined, the transfer coefficient of aminoisobutyric acid in nonischemic control animals ranged from 0.0018 +/- 0.0001 ml/g/min in diencephalon to 0.0049 +/- 0.0003 ml/g/min in cervical spinal cord. After 8 minutes of cardiac arrest followed by either 10 or 40 minutes of continuous sternal compression, there was no increase in the transfer coefficient. Likewise, during the immediate period after ventricular defibrillation, there was no increase in transfer coefficient despite the brief, transient hypertension. However, after 8 minutes of arrest, 6 minutes of cardiopulmonary resuscitation, and 4 hours of spontaneous circulation, the transfer coefficient was significantly increased by 59-107% in 10 of 11 regions rostral to the pons. Plasma volume in tissue measured by inulin was not elevated, suggesting that the increased transfer coefficient was not due to increased surface area. Thus, after an 8-minute period of complete ischemia, the blood-brain barrier remains intact during and immediately after resuscitation despite large vascular pressure fluctuations. However, in contrast to previous work on adult dogs, immature pigs are prone to a delayed increase in permeability, thereby allowing circulating substances greater access to the brain.

Aminoisobutyric Acids↗
PubMed1991

[Anesthesiology problems in Takayasu's syndrome].

Takayasu's disease is a rare form of nonspecific obliterative panarteritis of unknown origin, mainly located at supraaortic, renal, and pulmonary arteries and resulting in multiple stenoses and occlusion of major arteries. Predominantly young women in the first three decades of life are affected. Absence of arm pulses, vascular bruits, and retinopathy are classic symptoms. Another symptom is hypertension of the lower extremities and hypotension of the upper extremities, thus potentially impairing cerebral perfusion. A 25-year-old female patient with a 2-year history of Takayasu's disease presented for therapeutic abortion on the grounds of her medical condition. There were significant stenoses of the left common carotid artery and the internal carotid artery. The left subclavian artery was totally obliterated. The arterial blood supply to the left arm was accomplished by the left vertebral artery via a subclavian steal syndrome. Brachial and radial pulses were absent in both arms. General, spinal or epidural anesthesia can produce arterial hypotension. Blood pressure assessment at the lower extremities does not allow conclusions about perfusion of supraaortic arteries and cerebral perfusion pressure. Thus, a paracervical block was performed; sedation and analgesia were achieved with small doses of midazolam and alfentanil. We planned that if general anesthesia became necessary we would induce anesthesia with etomidate and alfentanil and maintain anesthesia by mask ventilation with nitrous oxide in oxygen and supplementary doses of alfentanil. Invasive monitoring such as arterial or Swan Ganz catheterization, was contraindicated because of the possibility that inflamed vessels would become irritated. Therefore, we only monitored ECG, blood pressure at the leg, ventilation parameters, and oxygen saturation at the ear lobe by pulse oximetry.(ABSTRACT TRUNCATED AT 250 WORDS)

Abortion, Therapeutic↗
PubMed1989

[Fentanyl versus sufentanil basic anesthesia. Hypnotic effect, muscle rigidity and efficacy of competitive muscle relaxants].

As induction agents for cardioanesthesia, sufentanil (S) and fentanyl (F) are usually employed in combination with nondepolarizing muscle relaxants. We investigated potential interactions of these opioids with the relaxant component, paying special regard to the role of muscular rigidity and opioid-induced alterations of hemodynamics. Narcotic anesthesia was induced randomly in 45 coronary artery bypass patients with either F (20 micrograms/kg) or S (4 micrograms/kg). After 6 min, neuromuscular blockade was initiated within each group randomly with either vecuronium (V) or pancuronium (P) (0.01 mg/kg each). During opiate administration, the times for cessation of spontaneous respiration and loss of responsiveness to verbal and tactile stimuli were measured. The degree of opiate-induced muscular rigidity, simultaneous changes in arterial paCO2, cardiac indices (CI) prior to opioid and relaxant administration, onset and recovery from neuromuscular blockade (by electromyographic train-of-four registration), and motor response to laryngoscopy and intubation were recorded. The onset of spontaneous apnea (TK = time to breathing upon command only) and unresponsiveness (TM = time to controlled mask ventilation) was significantly faster with S than with F. Muscular rigidity was moderate in 25% of patients and severe in 35%-40%, during the administration of both narcotics. No significant differences between S and F were observed. During ventilation by face mask, patients with clinically apparent rigidity showed a statistically significant mean increase in paCO2.(ABSTRACT TRUNCATED AT 250 WORDS)

Anesthetics↗
PubMed1988

[Models and methods in animal experiments in resuscitation].

Various animals models and several different methods are used in cardiopulmonary resuscitation (CPR) research. The animals used most frequently are dogs and pigs, but in each species thorax configurations, which might be an important factor in the mechanism of blood flow during CPR, are at great variance. The influence of anesthetics on cardiopulmonary and cerebral functions during and following resuscitation are largely unknown, and accordingly there is great variance in the techniques employed by individual researchers. The experimental design chosen with regard to the effect of heparin and epinephrine, induction, form, and duration of cardiac arrest as well as duration of CPR is often very different; comparisons are therefore difficult to make. During CPR ventilation is monitored using ventilatory pressure, frequency, tidal volume, and arterial blood gases. Thorax compressions are characterized by frequency, direction (sagittal, transversal), technique (mechanical, manual), relationship of time between compression and relaxation (50:50, 40:60), and depth of compression (power used, esophageal pressure, arterial blood pressure). Effects of CPR techniques are demonstrated during CPR by cardiovascular parameters. In addition to recording of blood pressure and blood flow, examination of regional perfusion rates using radioactive microsphere techniques is common. 24-h surveillance and extensive neurological tests are carried out during recovery following CPR.

Anesthesia↗
PubMed1987

Comparison of blood gases of ventilated patients during transport.

Three modes of ventilation during the transport of 30 ventilator-dependent patients were compared using blood gas variables. Ten were ventilated with a manually operated, ventilation bag (group C) and ten with a tidal volume meter at the exhalation valve of the ventilation bag (group V). Another ten patients (group O) were ventilated with a portable ventilator set to the minute volume (VE) given in ICU. VE was measured by volumetry as described above. Blood gases were analyzed in the ICU before and at the end of transport. In group C, significant decreases occurred in arterial (p less than .01) and central venous (p less than .05) PCO2, as well as in central venous PO2 (p less than .01). Arterial (p less than .05) and central venous (p less than .01) pH increased. Group V showed no statistically significant changes. In group O, arterial (p less than .01) and central venous (p less than .05) PCO2 decreased whereas arterial (p less than .01) and central venous (p less than .05) pH increased. We conclude that VE should be monitored during transport of ventilated patients.

Blood Gas Analysis↗
PubMed1987

[Future working conditions of anesthesiologists. Attempt at an analysis].

The present conditions of the anaesthesiologist's workplace are characterized by completely unacceptable circumstances, incompatibilities, inflexibility and unsafeness. Like inadequate cockpit conditions in airplanes, these workplace conditions pose considerable risks to the safety of patients and personnel. Taking into consideration the literature and our own views, we have proposed some changes which are essential for improving the working conditions of anesthesiologists: Ergonomic improvements of the anaesthesiological workplace in order to facilitate the anesthetist's performance, to provide him with adequate space, and to automatize repeated and relatively unimportant activities. Vital information about the patient's condition must be located in a position where they will dominate the anesthetist's attention. Information about medications, infusions, transfusions, etc. can be located on the left-hand side of the anesthetist. All other devices can be located beside the anesthetist or even behind him, as they are of minor importance. The most useful alternative to the present conditions would be to locate the information panels of primary and secondary monitoring devices to the immediate right, or on the right- und left-hand sides of the anesthetist at an angle of 15 degrees-30 degrees each. Furthermore, these information panels should be arranged so that they can be monitored using moving and slightly tilted screens. The most important of the patients, clinical parameters as well as the functions of the equipment should be monitored by alarms, warning devices, or simply indicators, which can easily be separated.(ABSTRACT TRUNCATED AT 250 WORDS)

Anesthesiology↗
PubMed1983

Changes of the immune response due to the absorption of antigenic protein or peptides.

Rabbits immunized against human gammaglobulin (HGG) were fed with either intact HGG or pepsin-digested HGG. Circulating antibodies were determined over an absorption time of 4 h. The oral application of antigenic peptides reduced circulating antibodies from 550 micrograms/ml to 120 micrograms/ml. A further parenteral antigen exposure to 50 mg HGG revealed that orally pretreated animals are protected against a marked blood pressure decrease due to antigen antibody reactions. One possible explanation for this phenomenon is that circulating antibodies are fixed in the wall of the gut by enterally applied antigenic peptides and eliminated into the lumen of the gastrointestinal tract. If this phenomenon can be extrapolated to human beings it would be a new therapeutic concept for the treatment of diseases in which circulating antibodies are of importance.

Animals↗