Anticoagulation monitoring during extracorporeal circulation with the Hepcon/HMS device.

OBJECTIVE: The objective of our study was to compare the standard protocol of anticoagulation to the Hepcon/HMS. METHOD: This study included forty-four patients who underwent coronary bypass grafting surgery (CABG), or biological aortic valve replacement (AVR). Unfractionated heparin (UH) was used for patients who underwent operations in the control group (n = 22) (300U/Kg of UH with a goal of an ACT of 400s). The heparin was antagonized dose/dose by protamine. For the patients who underwent operations in the HMS group (n = 22), the heparin and protamine doses were assessed by the Hepcon/HMS device. RESULTS: The sex ratio amounted to 1.93 (29 men and 15 women) and the mean age was 70 ± 11 years. The patients in the HMS group had a chest closure time that was significantly shorter than patients in the control group. The times were, respectively, 42 ± 15 minutes and 68 ± 27 minutes (p = 0.001). The protamine/heparin ratio was significantly lower in the HMS group (0.62 ± 0.13 vs. 1 ± 0.11) (p = 0.0001). The postoperative bleeding amounted to 804 ± 729 ml in the HMS group versus 1416 ± 1103 in the control group (p = 0.016). In multivariate linear regression analysis, only two independent factors were significantly associated with bleeding: the Hepcon/HMS (OR = 0.1-p = 0.03) and the preoperative hemoglobin rate (OR = 1.4 - p = 0.05). Postoperatively, within 72 hours, the red blood cell transfusion was 1.04 ± 1.5 units for the HMS group and 2.1 ± 1.87 units for the control group (p = 0.05). CONCLUSION: During cardiac surgery under CPB, heparin and protamine titration with the Hepcon/HMS device could predict a lower protamine dose and lower postoperative bleeding without higher thromboembolic events, and lower perioperative red blood cell transfusion with a shorter chest closure time.

Non-Kolbe electrolysis of N-protected-α-amino acids: a standardized method for the synthesis of N-protected (1-methoxyalkyl)amines.

Here, we report a standardized method for the synthesis of N-protected (1-methoxyalkyl)amines by the electrochemical decarboxylative α-methoxylation of α-amino acid derivatives using the commercially available, easy-to-use, compact ElectraSyn 2.0 setup. The use of equipment with a standardized power source, electrodes, and other accessories allows this experimental procedure to be easily transferred to any laboratory in the world. A simple workup and chromatography-free purification produced the products in excellent yields above 90%.

Micronuclei frequency in peripheral blood lymphocytes and levels of anti-p53 autoantibodies in serum of residents of Kowary city regions (Poland) with elevated indoor concentrations of radon.

INTRODUCTION: Ninety four residents of Kowary city (Poland) have been investigated for environmental radon exposure that ranged from 0.24 WLM to 9.6 WLM (activity concentration range: 35-2700 Bq/m3). Kowary was chosen because of uranium mineralisation in its close vicinity. METHOD: Whole population studied was divided into two groups: exposed to low radon activity concentrations resulting in the exposure of ≤0.55 WLM (value corresponding to the exposure to 100 Bq/m3 during whole year), and exposed to high radon activity concentration (>0.55 WLM). In the two groups two selected biomarkers in blood were assessed: the cytokinesis-block micronucleus assay (CBMN) on peripheral blood lymphocytes (PBL), and the levels of anti-p53 antibodies in serum measured because some data indicate increased expression of the antibodies in individuals after exposure to DNA damaging agents including radon. The potential confounding factors known to influence micronuclei (MN) frequency were also measured in serum: vitamin B12, folic acid, as well as total calcium. RESULTS: In the present study no significant correlation was found between MN frequency in PBL and radon exposure. Among all persons investigated only 11 had detectable levels of the anti-p53 antibodies, whereas only 3 persons had positive result. Therefore, the group was too small to perform any meaningful statistical analysis and to conclude on any association. Cigarette smoking did not significantly influence the number of MN. There was a significant positive correlation observed between MN frequency and age, as well as higher MN frequency was detected in women. CONCLUSION: The problem of the radon exposure is still unresolved and needs further studies on bigger human cohorts in order to search for more sensitive biomarkers.

Large-scale purification of human islets utilizing discontinuous albumin gradient on IBM 2991 cell separator.

A new method is described for the large-scale purification of human pancreatic islets with a discontinuous gradient of bovine serum albumin formed on an IBM 2991 cell separator. Fifteen human pancreases were processed, and after density-gradient centrifugation, a mean of 2643 islets/ml pancreatic digest were recovered with a mean purity of 63% and contained in 430 microliter mean vol. Viability of gradient-isolated islets was compared with that of non-density-gradient islets (handpicked) and showed no difference in function. This technique allows isolation of intact, viable human islets of Langerhans of sufficient purity for potential human transplantation.

Successful reversal of diabetes in nude rats by transplantation of isolated adult human islets of Langerhans.

A method is described in which the viability of isolated adult human islets of Langerhans can be assessed in vivo. The Rowett nude rat, made diabetic with streptozocin (STZ), has been used as the islet recipient in these studies. Although these animals are athymic and are able to accept xenogeneic grafts for prolonged periods, they are very susceptible to dehydration and infection once made diabetic. Therefore, a considerably shortened diabetes induction period was used. The basis of the study was to prepare pure adult human pancreatic islets that were cultured for 48 h. Nude rats were given 80 mg/kg i.v. STZ during islet isolation and were transplanted with 800-1000 islets under the renal capsule at 48 h. To monitor islet function, animals were bled regularly for random blood glucose measurements and were given a glucose tolerance test at day 20. The kidney containing the graft was removed on day 21 to allow histological assessment of the graft and to confirm that glucose control was due to the transplanted islets and was not secondary to reversion of the animal's own islets. Seven rats were transplanted, and five were deemed to have received viable human islets. Two rats that received islets from the same donor did not reverse their diabetes and were found by histology to have vacuolated islet structures with scant insulin-staining tissue under the kidney capsule. This method allows a definitive judgment of the ability of isolated adult human islets to reverse diabetes.

Corticosteroid determination in skin preparations by a reaction rate method.

A reaction rate method for the determination of beta-methasone, betamethasone valerate, triamcinolone acetonide, and fluocinolone acetonide is described. The method is based on a modification of the widely accepted blue tetrazolium reaction. Analysis times of 30--70 sec are required. Relative standard deviations of 0.3--1.9% are obtained, and the analytical working curves are linear. Analysis of pharmaceutical skin preparations by the new method gave results that correlated well with the time-consuming standard equilibrium method. Analysis of betamethasone and betamethasone valerate mixtures by measuring absorbance values at two different times was performed also.

Energy transport in closed quantum systems.

We examine energy transport in an ensemble of closed quantum systems driven by stochastic perturbations. One can show that the probability and energy fluxes can be described in terms of quantum advection modes (QAMs) associated with the off-diagonal elements of the density matrix. These QAMs play the role of Landauer channels in a system with discrete energy spectrum and the eigenfunctions that cannot be described as plane waves. In order to determine the type of correlations that exist between the direction and magnitudes of each QAM and the average direction of energy and probability fluxes we have numerically solved the time-dependent Schrödinger equation describing a single particle trapped in a parabolic potential well which is perturbed by stochastic ripples. The ripples serve as a localized energy source and are offset to one side of the potential well. As the result a nonzero net energy flux flows from one part of the potential well to another across the symmetry center of the potential. We find that some modes exhibit positive correlation with the direction of the energy flow. Other modes, that carry a smaller energy per unit of the probability flux, anticorrelate with the energy flow and thus provide a backflow of the probability. The overall picture of energy transport that emerges from our results is very different from the conventional one based on a system with continuous energy spectrum.

[Storage at room temperature does not change cisatracurium onset time: a prospective, randomized, double-blind controlled study]. / La température de conservation du cisatracurium ne modifie pas le délai d'action: étude randomisée, en double insu

OBJECTIVE: Storage of cisatracurium at room temperature seems to have no effect on its degradation in vitro contrary to the recommendations of storage at +4°C. The purpose of this study was to evaluate the influence of cisatracurium' s storage temperature on its onset time. STUDY DESIGN: Prospective, randomized, double-blind trial study. PATIENTS AND METHODS: Thirty patients were enrolled. The control group consisted of 15 patients receiving cisatracurium (0.15mg/kg) stored at room temperature and the intervention consisted of 15 patients receiving cisatracurium (0.15mg/kg) stored at +4°C. The primary endpoint was to compare cisatracurium onset time depending on the storage temperature. RESULTS: Cisatracurium onset time was 235 (180-292) seconds in the "room temperature" group vs. 240 (210-292) seconds in the "refrigerated" group. There was no difference between the onset of cisatracurium depending on the temperature of storage (p=0.51). Subgroups analysis in the "room temperature" group did not show any difference in cisatracurium onset depending on whether it was stored at room temperature for one, two or three weeks. Excellent intubation score was obtained for 100% of the patients. CONCLUSION: This study demonstrated that cisatracurium's storage at room temperature had no influence on its onset time. It provides an argument for the preservation of cisatracurium at room temperature for a period not exceeding 21 days. Monitoring the onset of curarization may increase the quality score of intubation.

Molecular dynamics and crystallization phenomenon of supercooled and glassy DNA and RNA nucleosides: ß-adenosine, ß-thymidine, and ß-uridine.

Nucleosides are chemical compounds that have an extremely important biological role; they can be found in all types of living organisms. They are crucial components from which DNA and RNA acids are built. In addition, nucleosides are key regulators of many physiological processes. In this paper, the molecular dynamics in the liquid and glassy state of three selected nucleosides, ß-adenosine, ß-thymidine, and ß-uridine, was investigated by means of dielectric spectroscopy. Our results revealed multiple relaxation processes associated with different types of molecular motions. Besides the primary α relaxation, two secondary modes in the glassy states of examined compounds were identified. Crystallization progress monitored by dielectric spectroscopy and x-ray diffraction technique at isostructural relaxation conditions revealed that the examined nucleosides possess completely different tendencies to recrystallize from the liquid as well as the glassy state. We have also made an attempt to predict the time scale of molecular motion below the glass transition temperatures of the respective nucleosides to discuss their potential stability at room temperature over prolonged storage time. Finally, combination of molecular mobility studies with evaluation of thermodynamic parameters from calorimetric measurements allowed us to discuss the fundamental roles of both kinetic and thermodynamic factors in governing the physical stability of the glassy state.

Synthesis of 1-(3-alkyl-2,3-dideoxy-D-pentofuranosyl)uracils with potential anti-HIV activity.

1-(3-Alkyl-2,3-dideoxy-alpha,beta-D-erythro-pentofuranosyl)uracils and 1-(3-alkyl-2,3-dideoxy-alpha,beta-D-threo-pentofuranosyl)uracils have been prepared from (E)-4,5-di-O-acetyl-2,3-dideoxy-aldehydo-D-glycero-pent-2-enose by a Michael addition reaction of the appropriate organocopper reagent followed in subsequent order by glycosidation of the resulting 3-alkyl-4,5-diacetoxypentanal with methanolic hydrogen chloride, protection with p-methoxybenzoyl chloride, and trimethylsilyl triflate catalyzed coupling with 2,4-di-O-(trimethylsilyl)uracil. The nucleosides were deprotected by treatment with 33% methylamine in absolute ethanol and separated by reversed-phase HPLC.

Synthesis of 3'-azolyl-2',3'-dideoxyhexose nucleosides.

1,8-Diazabicyclo[5.4.0]undec-7-ene salts of 2-methyl-4(5)-nitroimidazole or benzotriazole were obtained in crystalline form. Michael-type addition of these salts to (4S,5R)-(E)-4,6-di-O-acetyl-5-hydroxy-2-hexenal gave, after acetylation of the product, an isomeric mixture of acetylated 3-(azol-1-yl)-2,3-dideoxy-D-arabino-hexopyranosides and 3-(azol-1-yl)-2,3-dideoxy-D-ribo-hexofuranosides. Reaction of these peracetylated adducts with trimethylsilylated thymine in the presence of trimethylsilyl trifluoromethanesulfonate (TMS triflate) afforded the corresponding nucleosides which were deprotected by using methanolic ammonia. The nucleosides were found inactive against HIV-1 and HSV-1.

Free-radical synthesis of 3-(2-cyanoethyl)- and 3-(2-methoxycarbonylethyl)-2,3-dideoxy-alpha-D-erythro-pentofu ranoside and their application in the synthesis of potential antiviral nucleosides.

Free-radical reaction of different carbohydrate educts 2, 5, and 7 with acrylonitrile in the presence of tributyltin hydride and a radical initiator (AIBN) gave the methyl 3-(2-cyanoethyl)-2,3-dideoxypentofuranosides 3a and 6. Similar reaction of 2 with methyl acrylate gave 3-(2-methoxycarbonylethyl)-2,3-dideoxypentofuranose 3b. Nucleoside coupling of 3a with silylated uracil gave an anomeric mixture of beta- and alpha-nucleoside 8 and 9 which were deprotected to give 10 and 11, respectively. Similar reaction of 3b with silylated N4-isobutyrylcytosine gave 12 and 13 which were deprotected to give the final nucleosides 16 and 17, respectively. None of the compounds 10a, 11, 14-17 showed significant activity against HIV.

Monoclonal antibodies to human secretory "pregnancy-associated endometrial alpha 1-globulin," an insulin-like growth factor binding protein: characterization and use in radioimmunoassay, Western blots, and immunohistochemistry.

Monoclonal antibodies were raised against pregnancy-associated endometrial alpha 1-globulin (alpha 1-PEG), a 32 KD insulin-like growth factor binding protein (IGF-BP), which represents a major secretory product of the human decidualized endometrium during pregnancy. This class of IGF-BP has been implicated in the modulation of action, inhibitory and stimulatory, of insulin-like growth factors. Immunization with the protein purified from pregnancy endometrium resulted after myeloma fusion in the isolation of six hybridoma clones and the antibodies produced were characterized. The Ka of the antibodies ranged between 4.75 x 10(9) M-1 and 0.7 x 10(8) M-1. In Western blots all monoclonal antibodies reacted with purified protein of molecular weight 32 KD and specifically detected this IGF-BP species in culture medium and cytosolic extracts of pregnancy endometrium and amniotic fluid. The monoclonal antibodies appear to define three epitope-bearing regions as evidenced by their reactivity to polypeptide fragments of the protein. After synthesis and secretion by tissue explants in vitro the protein is susceptible to cleavage into fragments possessing different monoclonal antibody-defined reactivity. Employing immunohistochemical techniques the protein was principally localized to decidual cells in tissue sections of pregnancy endometrium and solely to these cells after enzymic digestion of the tissue. The implications of these results are discussed with respect to potential role of IGF-BP in the action of IGF upon the IGF-1 receptor-bearing populations, including lymphocytes and trophoblast cells, D in the decidua.