A randomised, controlled trial evaluating a low cost, 3D-printed bronchoscopy simulator.

Low-fidelity, simulation-based psychomotor skills training is a valuable first step in the educational approach to mastering complex procedural skills. We developed a cost-effective bronchial tree simulator based on a human thorax computed tomography scan using rapid-prototyping (3D-print) technology. This randomised, single-blind study evaluated how realistic our 3D-printed simulator would mimic human anatomy compared with commercially available bronchial tree simulators (Laerdal® Airway Management Trainer with Bronchial Tree and AirSim Advance Bronchi, Stavanger, Norway). Thirty experienced anaesthetists and respiratory physicians used a fibreoptic bronchoscope to rate each simulator on a visual analogue scale (VAS) (0 mm = completely unrealistic anatomy, 100 mm = indistinguishable from real patient) for: localisation of the right upper lobe bronchial lumen; placement of a bronchial blocker in the left main bronchus; aspiration of fluid from the right lower lobe; and overall realism. The 3D-printed simulator was rated most realistic for the localisation of the right upper lobe bronchial lumen (p = 0.002), but no differences were found in placement of a bronchial blocker or for aspiration of fluid (p = 0.792 and p = 0.057) compared with using the commercially available simulators. Overall, the 3D-printed simulator was rated most realistic (p = 0.021). Given the substantially lower costs for the 3D-printed simulator (£85 (€100/US$110) compared with > ~ £2000 (€2350/US$2590) for the commercially available simulators), our 3D-printed simulator provides an inexpensive alternative for learning bronchoscopy skills, and offers the possibility of practising procedures on patient-specific models before attempting them in clinical practice.

Safety and immunogenicity of a Pseudomonas aeruginosa O-polysaccharide toxin A conjugate vaccine in humans.

Lipid A-free polysaccharide (PS) isolated from Pseudomonas aeruginosa immunotype 5 lipopolysaccharide (LPS) was covalently coupled to toxin A via reductive amination. The PS-toxin A conjugate was comprised of 29.8% PS and 70.2% toxin A, possessed a molecular weight of greater than 1 X 10(6), was nontoxic for animals and was nonpyrogenic for rabbits at a dose of 50 micrograms/kg body wt when administered intravenously. The conjugate evoked only mild, transient reactions upon subcutaneous administration to human volunteers. Vaccination engendered immunoglobulin G (IgG) antibody, which neutralized the cytotoxic effect of toxin A and promoted the uptake and killing of P. aeruginosa in the presence of human polymorphonuclear leukocytes. Passively transferred IgG isolated from the serum of immunized donors was far more effective at preventing fatal P. aeruginosa burn wound sepsis than paired preimmunization serum. These studies establish the potential usefulness of such a PS-toxin A conjugate as a vaccine against P. aeruginosa.

Influenza vaccination in the elderly.

Influenza vaccination of elderly people has been shown to be useful. All vaccine types are well tolerated by higher age group vaccinees. Actually, whole virus vaccine, split virus vaccine and subunit vaccine are used in the vaccination of the elderly. Some studies have suggested that the induction of serum influenza antibody production was reduced in elderly persons when compared with that elicited in younger persons. However, investigations on the protective efficacy of influenza vaccination in the elderly have demonstrated a clinical protection of > or = 50% for preventing hospitalization. Live attenuated influenza vaccine conferred protection similar to that obtained with a conventional subunit vaccine. A virosomal unilamellar trivalent hemagglutinin vaccine showed promising serological results compared with those obtained with a whole cell vaccine and with a subunit vaccine, respectively. The actual policy is to vaccinate persons > or = 65 years of age and the groups that can transmit influenza to them. Each year's vaccine should contain three virus strains representing the influenza viruses that are likely to circulate in the upcoming winter.

Minor and trace sterols in marine invertebrates. 1. General methods of analysis.

3beta-Hydroxy sterols occurring at a concentration of at least 0.001% of the sterol mixtures of Pseudoplexaura porosa and Plexaura homomalla have been fractionated using a series of refined techniques and subsequently analyzed using combined gas chromatography-mass spectrometry (GC-MS) in the development of a procedure for examining the minor and trace components of marine sterol mixtures. A total of 49 sterols were found which spanned a molecular weight range of 274 to 440. In addition delta4-3-keto analogs of cholesterol, 24-methylcholesterol and gorgosterol were found in the extracts of P. homomalla. Initial separation of various natural sterol-containing conjugates and free sterols was found to have a number of advantages. Fractional digitonin precipitation and alumina column chromatography were found to possess greater sterol separation abilities than previously recognized. Many of the minor sterols were found to possess novel structures including a series of short side chain sterols, 19-nor sterols, 5beta-stanols and 4-monomethyl sterols for which structure elucidation work is continuing.

[Radiologic and ultrasound detection of gallstones]. / Radiologische und ultrasonographische Abklärung von Gallensteinen.

Ultrasonography (US) is the method of choice for evaluation of gallbladder stones with an accuracy of 96%. Number, size and calcification can be assessed by virtue of US reflection and attenuation. If more than five stones are present, the accuracy decreases. To determine the calcium content of stones more precisely, computed tomography can be used. This allows an assessment of the success rate of lithotripsy and chemolysis. Oral cholecystography is an alternative method of similar accuracy as US. It provides additional information about the patency of the cystic duct. In the presence of ductal stones, the accuracy of US decreases to 30%, mainly because of overlying bowel gas. Since 8 to 16% of all cases of cholecystolithiasis are accompanied by choledocholithiasis and since this entails a change in treatment, intravenous cholecystocholangiography with an accuracy of more than 90% is the method of choice in this case. Additionally, it provides knowledge on the biliary anatomy preoperatively. It does not, however, replace US, because opacification of the gallbladder is limited with this method. If intravenous cholecystocholangiography fails in case of impaired liver function, transcholecystic cholangiography or, in cases of dilated ducts, percutaneous transhepatic cholangiography can be used. Plain film radiography is not a suitable technique, since only 10 to 15% of all gallstones calcify.

Ellipsometry with polarisation analysis at cryogenic temperatures inside a vacuum chamber.

In this paper we describe a new variant of null ellipsometry to determine thicknesses and optical properties of thin films on a substrate at cryogenic temperatures. In the PCSA arrangement of ellipsometry the polarizer and the compensator are placed before the substrate and the analyzer after it. Usually, in the null ellipsometry the polarizer and the analyzer are rotated to find the searched minimum in intensity. In our variant we rotate the polarizer and the compensator instead, both being placed in the incoming beam before the substrate. Therefore the polarisation analysis of the reflected beam can be realized by an analyzer at fixed orientation. We developed this method for investigations of thin cryogenic films inside a vacuum chamber where the analyzer and detector had to be placed inside the cold shield at a temperature of T ≈ 90 K close to the substrate. All other optical components were installed at the incoming beam line outside the vacuum chamber, including all components which need to be rotated during the measurements. Our null ellipsometry variant has been tested with condensed krypton films on a highly oriented pyrolytic graphite substrate (HOPG) at a temperature of T ≈ 25 K. We show that it is possible to determine the indices of refraction of condensed krypton and of the HOPG substrate as well as thickness of krypton films with reasonable accuracy.

Antigangrenous effect of an odontological preparation.

Experiments were performed in order to compare the antigangrenous effect of Pyralvex Berna and its components (alcoholic salicylic acid solution and extractum rhei, resp.) with that of an antiphlogistic standard preparation (phenylbutazone). In this experimental model the tails of albino mice are put into water of 55 degrees C for 10 sec. This results in the loss of part of the tail within the following days. In the present investigation, the tail of part of the animals was put into one of the solutions to be examined for 5 sec immediately after exposure to heat as well as on the following 5 days. In the controls 55.65% (on an average) of the original length of the tail were lost, in the animals treated with phenylbutazone 19.10% (on an average) and in the animals treated with Pyralvex 27.25% (on an average) were lost. Thus, the antigangrenous effect of Pyralvex was 77% of that of phenylbutazone. The statistical analysis of the results obtained in the 4th and 5th groups demonstrates that this effect is mainly due to extractum rhei, the antigangrenous effect of which is statistically not significantly different from the antigangrenous effect of Pyralvex (p greater than 0.4).

[Electrocardiogramme in anaphylactic shock in humans (author's transl)]. / Das Elektrokardiogramm im anaphylaktischen Schock des Menschen

Twenty clinical cases described in the literature were gathered, in which electrocardiographic tracings had been recorded. Electrocardiographic changes were found in all cases, such as sinus tachycardia (12 times), impaired electrical conduction (5 times), ventricular overexcitability (7 times), high P-wave (6 times), changes of the ST (10 times), and of the T-wave (18 times). The reason for these changes might be of a complex nature. Based on experimental investiagations mentioned in the discussion, it may be assumed that beside a direct effect on the myocardial cells, the following mechanisms could have influenced the electrical heart potentials: 1. a constriction of the coronary vessels, 2. a pulmonary vascular constriction, 3. an aggregation of thrombocytes, 4. a peripheral vascular dilatation, 5. a bronchiolar constriction.

[Physiopathology of anaphylactic and anaphylactoid shock. A cooperative retrospective study]. / Pathophysiologie des anaphylaktischen und anaphylaktoiden Schocks. Eine kooperative retrospektive Studie.

The pathophysiology of anaphylactic and anaphylactoid shock states suggests that the rapidly initiated, intensive therapeutic measures to be taken must involve: breathing (ventilation) of (with) 100% oxygen, continuous or semi-continuous sympathicomimetic therapy (epinephrine, isoprenalin, orciprenalin) avoiding excessive single doses, rapid intensive volume substitution, control of metabolic acidosis, bronchospasmolytic therapy, in case of laryngospasm intubation, if not possible coniotomy or transtracheal punction. In case of circulatory arrest possibly also cardiac massage, defibrillation, lidocain, cardioversion. In a retrospective study 91 cases of anaphylactic and anaphylactoid shock were analyzed. Cutaneous vascular changes. Vasodilation was reported in 30 cases, vasoconstriction in 15 cases. Hypovolemia. CVP as measured in 23 cases was less than or equal to 2 cmH2O in 12 cases; in 4 of these cases the early finding and in 2 a rather low hematocrit are in favour of venous blood sequestration. In 2 cases the increase of the hematocrit suggests an extravasation of as much as 1,2 and 1,81 of plasma, respectively. Increase of pulmonary arterial pressure. CVP increased in 2 out of 9 cases suggesting a high pulmonary arterial pressure. Decreased cardiac output (CO). In 3 cases CO as determined in a late shock phase diminished by 37--55%. Blood gas changes. PaO2 was as low as 47--61 mmHg in 4 out of 8 cases, PaCO2 being 29--34 mmHg in 2 of them. It suggests an insufficient oxygen transport. Myocardial involvement. Arrhythmias (non sinus-) were found in 38 cases, of which 14 ventricular arrhythmia and 13 asystole. Serious wave deformation concerned QRS (3), AV-block (2), intraventricular blocks (4). 5 times the reaction resulted in myocardial infarction. A localized coronary spasm in anayphylactic shock was observed during a coronary angiography. Respiratory impairment. Severe respiratory impairment was associated with anaphylactic and anaphylactoid shock in 31 cases (26 bronchospasm, 4 apnea, 1 laryngospasm).

[Local reactions after repeated tetanus vaccinations]. / Lokale Reaktionen nach wiederholten Tetanusimpfungen.

Subjects who had exhibited a strong local reaction after vaccination with tetanus toxoid showed a high serum antitoxin titer. This observation confirms earlier findings published in the United States. Since the falloff rate in tetanus antitoxin, year by year, is no more than 30%, such patients should not receive a new booster injection in the following 10 years unless the risk of tetanus is considered great. When boostering these persons, the dose of tetanus toxoid can be reduced to 1-2 Lf.

[Intravenous administration of anti-D hyperimmunoglobulin after mismatched transfusion (author's transl)]. / Anti-D-Hyperimmunglobulin intravenös nach Transfusionsfehler

620 ml of 0 Rh-positive blood (310 ml CCD.ee + 310 ml CcD.EE) were administered to a 27-year-old 0 Rh-negative (ccddee) woman in connection with an emergency curettage. 16 hours after this mismatched transfusion an intravenous infusion of anti-D hyperimmunoglobulin was started: 8000 mug (13 mug/ml blood) were given within 14 hours (570 mug/h) under strict supervision. The 10% immunoglobulin preparation had been diluted 20 times. There were only slight variations in heart rate and blood pressure, slight fever and mild increase in serum bilirubin after the infusion. There was slight haemoglobinuria in one urine sample, but no signs of kidney damage. The direct Coombs test was slightly positive after two days, negative after four and six days. The indirect Coombs test was negative after six months. The patient has not become pregnant since. Slow intravenous infusion of highly diluted anti-D hyperimmunoglobulin, under strict clinical supervision, is probably appropriate for Rh prophylaxis after transfusion mismatch. The dose of 13 mug/ml could probably be considerably reduced. 250 mug anti-D per hour should not be exceeded.

[Booster vaccination with a diphtheria-tetanus vaccine for dermo-jet with low diphtheria toxoid content]. / Auffrisch-Impfung mit einem Diphtherie-Tetanus-Impfstoff für Dermo-Jet mit niedrigem Diphtherietoxoidgehalt

Indications are provided on how the organization of polyvaccinations against tuberculosis, poliomyelitis and diphtheria-tetanus in school collectivities can be rationalized. 19 persons aged 19-20 years were vaccinated intradermally with 1.5 Lf diphtheria toxoid and 15 Lf tetanus toxoid (contained in 0.1 ml) by means of a single injection with a jet injector (Dermo-Jet). In cases which had not previously been immunized, vaccination with the toxoid doses employed did not induce detectable antitoxin titers. In all cases which had previously been immunized the antitoxin titers after the booster injection were at least 400 times higher than the protection threshold for diphtheria and 1700 times higher than the protection threshold for tetanus. This was also the case in preimmunized cases which had no detectable antitoxin titer before the vaccination. The increase in antitoxin titer was inversely proportional to the prevaccinal titer in the manner of a logarithmic exponential function. It may be concluded from these results that the benefit of a booster vaccination is particularly high in poorly immunized persons whereas it is clearly limited in cases showing a high prevaccinal titer. The well tolerated intradermal vaccination with the jet injector (Dermo-Jet) can be considered as equivalent to the subcutaneous technic. From the point of view of organization (time consumption, problems of sterilization) this method is much preferable to intramuscular or subcutaneous vaccination.

[Influenza vaccination with a trivalent whole virus vaccine]. / Grippeimpfung mit einem trivalenten Vollvirus-Impfstoff.

During winter 1979/80 21 trainee nurses aged 18-22 years were vaccinated once with an intact influenza vaccine containing for the first time, two different virus-A subtypes as well as a B-strain. 22 trainee nurses from the same school served as controls. A greater than or equal to 4-fold seroconversion (2 dilution steps) was observed in 67% (A/Texas/77), 83% (A/USSR/77) and 57% (B/Hongkong/73) of the vaccinated, but only in 5% (A/Texas/77, one case) of the non-vaccinated. In the vaccinated group 36 reciprocal titers rose from < 80 to greater than or equal to 80 so that, with 3 exceptions (A/USSR/77, all vaccinees had a reciprocal titer of greater than or equal to 80 after 28 days. In the unvaccinated group only 3 reciprocal titers rose from < 80 to greater than or equal to 80 (A/Texas/77), so that 42 reciprocal titers were still below 80 after 28 days.