Identification of internal poly(A) tracts (IPATs) of variable lengths in a novel tobacco rattle virus RNA2 in potatoes.

The nucleotide (nt) sequences of two closely related isolates (CeWF-2 and CeWGH-2) of a novel tobacco rattle virus (TRV) RNA2 were determined. The sequences of their RNA2-specific regions were almost identical and contained four open reading frames (ORFs) in an arrangement similar to that found in the previously described TRV TpO1 RNA2. Their predicted ORF 1 gene products shared 97 % amino acid sequence identity with the TpO1 coat protein, but the ORF 2 and ORF 3 gene products shared only 82 % sequence identity, and no appreciable sequence similarity was found between the CeWF-2/CeWGH-2 and TpO1 ORF 4 gene products. In the CeWGH-2 sequence, the RNA2-specific and RNA1-related regions were separated by seven adenine (A) residues. In CeWF-2, however, an internal poly(A) tract (IPAT) of variable size consisting of ca. 20 to 30 (A) residues was found. This is the first report of an IPAT occurring in a tobravirus RNA2.

Molecular characterization of a new tobacco rattle virus (TRV) RNA2 and identification of different TRV RNA1/RNA2 pairings in various potato-growing areas in Germany.

The almost complete nucleotide sequences lacking only the short primer-derived 5' and 3' ends were determined for two closely related isolates of a new tobacco rattle virus (TRV) RNA2, i.e., ByKT (Bav)-2 and ByKT (LS)-2. These isolates originated from corky-ringspot-affected potato-growing areas in southern Germany (Bavaria) and northern central Germany (Lower Saxony), respectively, where they were associated with distinct supporting TRV RNA1s. In potatoes in other parts of Germany, TRV RNA2s closely related to TRV TpO1 RNA2 were identified. They, too, were associated with distinct TRV RNA1s in different parts of the country.

A new variant of the basophil activation test for allergen-induced basophil CD63 upregulation. The effect of cetirizine.

OBJECTIVE: The aim of our study was to determine the diagnostic usefulness of a newly developed basophil activation test (BAT) in patients allergic to Dermatophagoides pteronyssinus and pollens. We also analyzed the influence of cetirizine on CD63 upregulation. This popular antihistamine strongly inhibits skin tests, but its impact on BAT sensitivity remains unknown and deserves at least preliminary determination. METHODS: The study sample comprised 22 patients allergic to house dust mite and pollens and 19 healthy controls. All participants underwent skin prick testing and the newly developed flow-cytometric basophil activation test. The protocol for allergen-induced basophil CD63 upregulation consisted of whole blood samples that were processed and stained with anti-CCR3/CD63 antibodies added to the buffer at the beginning of stimulation. Skin prick tests and BAT were performed twice--before and 2 hours after ingestion of 10 mg of cetirizine. RESULTS: The new BAT is characterized by its short processing time, easy basophil gating, and strong CD63 upregulation with very high sensitivity and excellent specificity. Our results suggest that allergen-induced CD63 upregulation by higher doses of allergens is not inhibited 2 hours after administration of cetirizine (unlike skin prick tests). CONCLUSION: The BAT is a very useful and precise method for the diagnosis of allergy to aeroallergens. It is not influenced by cetirizine.

Inhibition of nitric oxide improves coronary perfusion pressure and return of spontaneous circulation in a porcine cardiopulmonary resuscitation model.

OBJECTIVE: During spontaneous circulation, nonspecific inhibition of nitric oxide synthase by N(G)-nitro-L-arginine methyl ester (L-NAME) increases systemic vascular resistance and, therefore, mean arterial pressure. If this effect can be extrapolated to cardiopulmonary resuscitation (CPR), administering L-NAME during CPR may be beneficial by maintaining or even improving coronary perfusion pressure, and hence successful defibrillation. DESIGN: Prospective, randomized laboratory investigation using an established porcine model with instrumentation for hemodynamic variables, blood gases, and defibrillation attempt. SETTING: University medical center experimental laboratory. SUBJECTS: Ten domestic pigs. INTERVENTIONS: After 4 mins of ventricular fibrillation, ten animals were randomly assigned to receive L-NAME (25 mg/kg; n = 5) or saline placebo (n = 5) (given in two doses) after 3 and 13 mins of CPR, respectively. Defibrillation was provided 5 mins after the second dose of active drug or placebo. MEASUREMENTS AND MAIN RESULTS: Mean +/- sem coronary perfusion pressure was significantly (p < .05) higher 90 secs (27 +/- 3 vs. 17 +/- 3 mm Hg), 10 mins (28 +/- 3 vs. 14 +/- 2 mm Hg), and 15 mins (21 +/- 5 vs. 7 +/- 3 mm Hg) after the first L-NAME administration compared with saline placebo. Mean +/- sem coronary perfusion pressure remained significantly higher 90 secs and 5 mins after the second L-NAME vs. saline placebo administration (19 +/- 4 vs. 6 +/- 4 mm Hg, and 17 +/- 3 vs. 4 +/- 4 mm Hg). After 22 mins of cardiac arrest, including 18 mins of CPR, four of five pigs in the L-NAME group were successfully defibrillated, and survived the 60-min postresuscitation phase. In the placebo group, none of five pigs could be defibrillated successfully (p < .05). CONCLUSIONS: Nonspecific blockade of nitric oxide synthase with L-NAME during CPR was associated with an increase in coronary perfusion pressure and resulted in significantly better initial resuscitation when compared with saline placebo.

Vasopressin-mediated adrenocorticotropin release increases plasma cortisol concentrations during cardiopulmonary resuscitation.

OBJECTIVE: Vasopressin is a possible stimulus for both adrenocorticotropin (ACTH) and endothelin-1 release. The aim of this study was to compare plasma concentrations of ACTH, cortisol, and endothelin-1 after epinephrine or vasopressin administration in an experimental animal model of cardiopulmonary resuscitation (CPR). DESIGN: Prospective, randomized, controlled animal study. SETTING: A university research laboratory. SUBJECTS: Fourteen 12- to 14-wk-old domestic pigs. INTERVENTIONS: After 4 mins of cardiac arrest and 3 mins of external chest compression, the pigs were randomly assigned to receive either 0.045 mg/kg epinephrine (n = 7) or 0.4 units/kg vasopressin (n = 7). At 5 mins after drug administration, defibrillation was attempted. MEASUREMENTS AND MAIN RESULTS: Coronary perfusion pressure, ACTH, cortisol, and endothelin-1 were measured before cardiocirculatory arrest, during CPR before drug administration, and at 90 secs and 5 mins after drug administration. Coronary perfusion pressure was comparable between groups. All seven animals in the vasopressin group survived, but only one pig in the epinephrine group survived (p = .005). ACTH and cortisol concentrations remained unchanged in epinephrine-treated animals, but increased significantly after vasopressin administration and were significantly higher than in epinephrine-treated animals 5 mins after drug administration. Endothelin-1 concentrations remained unchanged during the study period and were comparable between both groups. CONCLUSIONS: Vasopressin is a potent stimulus for ACTH secretion, but does not trigger endothelin-1 release from vascular cells during cardiac arrest and CPR. The increased plasma cortisol concentrations caused by the enhanced ACTH release after vasopressin may be one factor contributing to the improved outcome repeatedly observed with vasopressin in animal models of CPR.

Comparison of epinephrine and vasopressin in a pediatric porcine model of asphyxial cardiac arrest.

OBJECTIVE: This study was designed to compare the effects of vasopressin vs. epinephrine vs. the combination of epinephrine with vasopressin on vital organ blood flow and return of spontaneous circulation in a pediatric porcine model of asphyxial arrest. DESIGN: Prospective, randomized laboratory investigation using an established porcine model for measurement of hemodynamic variables, organ blood flow, blood gases, and return of spontaneous circulation. SETTING: University hospital laboratory. SUBJECTS: Eighteen piglets weighing 8-11 kg. INTERVENTIONS: Asphyxial cardiac arrest was induced by clamping the endotracheal tube. After 8 mins of cardiac arrest and 8 mins of cardiopulmonary resuscitation, a bolus dose of either 0.8 units/kg vasopressin (n = 6), 200 microg/kg epinephrine (n = 6), or a combination of 45 microg/kg epinephrine with 0.8 units/kg vasopressin (n = 6) was administered in a randomized manner. Defibrillation was attempted 6 mins after drug administration. MEASUREMENTS AND MAIN RESULTS: Mean +/- SEM coronary perfusion pressure, before and 2 mins after drug administration, was 13 +/- 2 and 23 +/- 6 mm Hg in the vasopressin group; 14 +/- 2 and 31 +/- 4 mm Hg in the epinephrine group; and 13 +/- 1 and 33 +/- 6 mm Hg in the epinephrine-vasopressin group, respectively (p = NS). At the same time points, mean +/- SEM left ventricular myocardial blood flow was 44 +/- 31 and 44 +/- 25 mL x min-(1) x 100 g(-1) in the vasopressin group; 30 +/- 18 and 233 +/- 61 mL x min(-1) x 100 g(-1) in the epinephrine group; and 36 +/- 10 and 142 +/- 57 mL x min(-1) x 100 g(-1) in the epinephrine-vasopressin group (p < .01 epinephrine vs. vasopressin; p < .02 epinephrine-vasopressin vs. vasopressin). Total cerebral blood flow trended toward higher values after epinephrine-vasopressin (60 +/- 19 mL x min(-1) x 100 g(-1)) than after vasopressin (36 +/- 17 mL x min(-1) x 100 g(-1)) or epinephrine alone (31 +/- 7 mL x min(-1) x 100 g(-1); p = .07, respectively). One of six vasopressin, six of six epinephrine, and four of six epinephrine-vasopressin-treated animals had return of spontaneous circulation (p < .01, vasopressin vs. epinephrine). CONCLUSIONS: Administration of epinephrine, either alone or in combination with vasopressin, significantly improved left ventricular myocardial blood flow during cardiopulmonary resuscitation. Return of spontaneous circulation was significantly more likely in epinephrine-treated pigs than in animals resuscitated with vasopressin alone.

Intraosseous vasopressin improves coronary perfusion pressure rapidly during cardiopulmonary resuscitation in pigs.

OBJECTIVE: Intravenous administration of vasopressin during cardiopulmonary resuscitation (CPR) may be more effective than optimal doses of epinephrine. The main purpose of this study was to determine whether intraosseous vasopressin achieves serum drug levels comparable with intravenous doses during CPR and, additionally, to evaluate the effects of intraosseous vasopressin during CPR. DESIGN: Prospective, randomized laboratory investigation using an established porcine model with instrumentation for measurement of hemodynamic variables, blood gases, and return of spontaneous circulation. SETTING: University hospital laboratory. SUBJECTS: Twelve domestic pigs. INTERVENTIONS: After 4 mins of untreated ventricular fibrillation and 3 mins of CPR, 12 pigs were randomized to be treated with intravenous administration of vasopressin (0.8 unit/kg vasopressin; n = 6) or intraosseous vasopressin (0.8 unit/kg vasopressin; n = 6). Defibrillation was performed 5 mins after drug administration to attempt the return of spontaneous circulation. MEASUREMENTS AND MAIN RESULTS: At both 90 secs and 5 mins after drug administration, intravenous and intraosseous administration of vasopressin resulted in comparable mean (+/-SEM) coronary perfusion pressure (43+/-4 vs. 44+/-3 and 30+/-2 vs. 37+/-2 mm Hg, respectively) and vasopressin plasma concentrations (13,706+/-1,857 vs. 16,166+/-3,114 pg/mL and 10,372+/-883 vs. 8246+/-2211 pg/mL, respectively). All animals in both groups were successfully resuscitated; pigs that received intraosseous vasopressin had a significantly higher (p < .05) mean arterial (92+/-6 vs. 129+/-12 mm Hg) and coronary perfusion pressure (84+/-11 vs. 119+/-11 mm Hg) at 5 mins of return of spontaneous circulation. CONCLUSIONS: Intraosseous vasopressin resulted in comparable vasopressin plasma levels, hemodynamic variables, and return of spontaneous circulation rates as did intravenous vasopressin. Intraosseous vasopressin may be an alternative for vasopressor administration during CPR, when intravenous access is delayed or not available.

Percentage of hypochromic red blood cells as predictor of erythropoietic and iron response after i.v. iron supplementation in maintenance haemodialysis patients.

BACKGROUND: The percentage of hypochromic red blood cells (RBC), defined as those with a cellular haemoglobin < 28 g/dl has been suggested to be a sensitive marker of functional iron deficiency in maintenance haemodialysis (HD) patients. Thus, during rHuEpo therapy an increase in hypochromic RBC to > 10% would indicate that more intensive iron supplementation may be required. METHODS: We investigated 70 HD patients 57.1 +/- 15.3 years old and on maintenance HD for 66.3 +/- 47.9 months without blood loss from gastrointestinal bleeding or from the vascular access, without surgery and without infectious disease or malignancy. During the study period of 12 weeks, each patient received in i.v. dose of 800 mg ferrogluconate. Haemoglobin, haematocrit, and the percentage of hypochromic RBC were measured before and every 4 weeks after the start of the study; serum ferritin, zinc protoporphyrin (ZPP) and C-reactive protein (CRP) were measured at the beginning (baseline) and end of the study. RESULTS: At baseline the percentage of hypochromic RBC was < or = 5.0% in 28 patients, > 5.0 and < or = 10.0% in 25 patients and > 10.0% in 17 patients, suggesting functional iron deficiency in at least 42 patients. Nine patients had serum ferritin values < 100 micrograms/1; nonetheless in these patients the median percentage of hypochromic RBC was 5.9% (range 0.9-14.3%), indicating that an absolute iron deficiency can occur in the presence of normal amounts of hypochromic RBC. There was a significant correlation between serum ferritin levels and hypochromic RBC at the end, but not at the beginning, of the study. However, there was no correlation between ZPP and hypochromic RBC at any time during the study. During i.v. iron supplementation the rHuEpo dose could be reduced by 8.5% in patients with hypochromic RBC < or = 5.0%, by 11.3% in patients with hypochromic RBC > 5.0 and < or = 10.0% and by 23.4% in patients with hypochromic RBC > 10.0%, demonstrating the benefit of i.v. iron in patients with functional iron deficiency. In HD patients in whom serum ferritin levels remained below 290 micrograms/l until the end of the study, a significant reduction of the rHuEpo dosage could be obtained during i.v. iron therapy. This was not the case in patients with serum ferritin > 290 micrograms/l after iron supplementation. We found that the percentage of hypochromic RBC is the most sensitive parameter for predicting hyporesponsiveness in CRP-positive patients. HD patients with hypochromic RBC > 6% and low to moderate increases in serum ferritin levels after i.v. iron supplementation significantly benefit from i.v. iron therapy compared to HD patients with hypochromic RBC < 6%. CONCLUSIONS: Two different aspects should be taken into consideration in HD patients treated with rHuEpo and concomitant i.v. iron therapy: (1) response of the erythropoietic system to rHuEpo, and (2) adequate delivery of the supplemented iron to the erythropoietic system. The patient's percentage of hypochromic RBC and increase in serum ferritin after i.v. iron supplementation should be used to decide whether or not i.v. iron should be given and to monitor this type of therapy in HD patients.

Shed mediastinal blood in 500 elective cardiac surgery patients: is there enough for retransfusion routinely?

OBJECTIVE: Since an increased use of several blood salvaging measures has contributed to a reduction in perioperative blood loss and the requirement for banked blood in recent years, the aim of this study was to establish current postoperative drainage losses in order to evaluate whether homologous retransfusion may be a useful measure to reduce autologous transfusion in elective cardiac surgery. DESIGN/SETTING: This prospective clinical investigation was performed at a University Intensive Care Unit during the first six hours following cardiac surgery. PATIENTS: 373 men and 127 women undergoing elective cardiac surgery were investigated. MEASURES: The amount of shed blood was measured four and six hours postoperatively. RESULTS: The average blood loss was higher in men than in women both in all operations as a whole (men, four hours: 223+/-73 ml, six hours 270+/-95 ml; women, four hours: 156+/-25 ml, six hours 195+/-22 ml), in valve replacement (men, four hours: 299+/-87 ml, six hours 350+/-101 ml; women, four hours: 187+/-30 ml, six hours: 219+/-31 ml) and in coronary artery bypass grafting (men, four hours: 197+/-69 ml, six hours: 242+/-83 ml; women, four hours: 128+/-15 ml, six hours: 173+/-18 ml). A blood loss of 400 ml was exceeded in 13% of men after valve replacement four and six hours postoperatively. In all other groups, less than 8% of patients had a loss of more than 400 ml both after four and after six hours. CONCLUSIONS: Postoperative drainage losses in elective cardiac surgery patients are small and a measurable advantage from retransfusion seems to be unlikely. We therefore endorse the routine use of shed mediastinal blood retransfusion in these patients.

Effect of 6R-L-erythro-5,6,7,8-tetrahydrobiopterin and infusion of L-tyrosine on the in vivo L-[beta-11C] DOPA disposition in the monkey brain.

The effect of 6R-L-erythro-5,6,7,8-tetrahydrobiopterin (6R-BH4) and L-tyrosine infusion on [11C]dopamine synthesis was analyzed in the striatum of Rhesus using positron emission tomography (PET). The rate for decarboxylation from L-[beta-11C]DOPA to [11C]dopamine was calculated using a graphical method with cerebellum as a reference region. Although the peripheral administration of 6R-BH4 at low dose (2 mg/kg) did not provide a significant increase in the rate of dopamine biosynthesis, a high dose of 6R-BH4 (20 mg/kg) induced an elevation of the rate. This 6R-BH4-induced elevation of the dopamine synthesis rate was further dose-dependently enhanced by the continuous infusion of L-tyrosine (0.2 and 1.0 mumol/min/kg). L-Tyrosine infusion with a rate of 1.0 mumol/min/kg caused an enhancement of the rate even during low dose administration of 6R-BH4 (2 mg/kg). L-Tyrosine infusion alone did not induce any elevation of the dopamine biosynthesis rate. The analysis of plasma indicated that the metabolic ratios of L-[beta-11C]DOPA to each metabolite were not affected by 6R-BH4 and/or L-tyrosine infusion. The results suggest that the low dose loading of tyrosine facilitates the activity of 6R-BH4 on the presynaptic dopamine biosynthesis, and also that the combined effects can be monitored by PET using L-[beta-11C]DOPA as a biochemical probe.

[What's new in cardiopulmonary resuscitation? American Heart Association]. / Was ist neu in der kardiopulmonalen Reanimation?

A strong consensus was reached for several changes in the guidelines for cardiopulmonary resuscitation (CPR) and emergency cardiac care (ECC) in the 1992 conference on CPR and ECC held by the Emergency Cardiac Care Committee of the American Heart Association. These new recommendations, together with differing recommendations of the European Resuscitation Council, are described. An unresponsive person with spontaneous respirations should be placed in the recovery position if no cervical trauma is suspected. Compared with endotracheal intubation, other airway-protecting devices such as combination esophageal-tracheal tubes are of minor acceptance. During ventilation, the time for filling the lungs is increased to 1.5-2 s to decrease the likelihood of gastric insufflation. Delivery of i.v. drugs can be enhanced by an i.v. flush of sodium chloride. In endotracheal drug administration, higher doses and drug dilution are recommended. In infants and children up to 6 years of age, the value of intraosseous drug administration is emphasized. For pulseless adult victims, the initial dosage of epinephrine of 1 mg i.v. remains unchanged. For repeat doses, high-dose epinephrine up to 0.1 mg/kg is classified as of uncertain but possible efficacy. For lidocaine, the recommended i.v. dosage is 1.5 mg/kg. Sodium bicarbonate and calcium are not routinely recommended for resuscitation. For atropine, the maximum dose is 0.04 mg/kg. If hypomagnesaemia is present in recurrent and refractory ventricular fibrillation, it should be corrected by administration of 1 to 2 g magnesium sulfate i.v. Thrombolytic agents are classified as useful and effective in acute myocardial infarction and should be administered as early as possible. Glucose-containing fluids are discouraged for resuscitative efforts.

Thinking with images or thinking with language: a pilot EEG probability mapping study.

This pilot EEG mapping study was designed to explore thinking processes using complex mental imagery and thought processes. EEG was recorded with 19 electrodes (10/20 system against averaged ear lobe signals) while volunteers (n = 42) performed two separate tasks: visualization of an abstract concept and interpretation of a painting. Average spectral parameters such as amplitude, local and interhemispheric coherences were computed for five frequency bands (theta, alpha, beta 1, 2 and 3). Results indicate that the frontal regions are strongly involved during these tasks as evidenced by coherence changes. Changes are also present in temporal, parietal and occipital regions and are discussed in relation to information processing with the frontal regions considering the different cognitive functions required by the tasks.

[Light and scanning electronmicroscopic studies of border surfaces of aluminum oxide-ceramic implants in the dog mandible]. / Lichtoptische und rasterelektronenmikroskopische Untersuchungen an der Grenzfläche von Implantaten aus Aluminiumoxid-Keramik im Unterkieferknochen von Hunden.

The mandibular bone of beagles as well as foxhounds and the border surfaces in the area of implants of dense Al2O3 ceramic were examined by scan electron microscope and optically in undecalcified preparations 4 and 6 months after the start of the experiment. All implants healed without foreign body or inflammatory reaction and exhibited a firm contact with the newly-formed surrounding osseous tissue. The border surface was always formed by osseous tissue and bone marrow and not by connective tissue. The bony border surface presented a casting of the structure proper of the ceramics as well as orderly remodelling. The tooth implants which had in part been under strain for a long time were surrounded by newly formed osteoid bone and supported by bone trabeculi. In the immediate proximity of the surface of the ceramic vital osteophites were found. The gum which was placed in a groove of the step implants showed firm epithelial covering and orderly fibrous texture.