Comparison of gamma-ray dosimeters in a field study in the Chernobyl exclusion zone.

Five different models of dosimeters were compared in the Chernobyl Inner Exclusion Zone by measuring gamma radiation in 12 locations. We used an instrument made by Mirion Technologies, Inc., as the reference, since that instrument had an NIST-traceable calibration. Two models of dosimeters gave radiation values similar to the Mirion at all levels of radiation encountered. Two other models gave similar values to the Mirion instrument at low radiation levels but not at higher radiation levels encountered. These results offer a caution regarding the accuracy of inexpensive commercially available radiation instruments. Implications: Comparison of gamma ray dosimeters in the Chernobyl Exclusion Zone showed varying agreement with an NIST-calibrated instrument, as well as varying linearity of response to ambient radiation. These results suggest caution regarding accuracy of inexpensive dosimeters. However, dosimeters used that were manufactured in Ukraine exhibited good agreement with the reference instrument.

ß2-Adrenoceptor gene variants affect vasopressor requirements in patients after thoracic epidural anaesthesia.

BACKGROUND: While the ß2-adrenoceptor pathway is essential for cardiovascular regulation, the impact of ADRB2 gene variations on circulatory responses is unclear, possibly due to neural compensatory mechanisms. We tested the hypotheses that (i) sympathetic block by thoracic epidural anaesthesia (TEA) unmasks the influence on arterial pressure of genetic variations and (ii) vasopressor requirements during TEA depend on ADRB2 gene variation. METHODS: Ninety-three elective patients undergoing abdominal surgery were included prospectively. After epidural bupivacaine 0.5% (15 mg test dose+50 mg), arterial pressure, heart rate, and progression of sensory block were measured for 20 min in the supine awake state and for 20 min after standardized anaesthetic induction of general anaesthesia. The primary endpoint was cumulative dose of the α-adrenoreceptor agonist phenylephrine administered to sustain a mean arterial pressure >70 mm Hg. The ADRB2 polymorphisms Arg16Gly and Gln27Glu were genotyped using Slowdown-PCR. RESULTS: After TEA, 86 (93%) patients required phenylephrine. The mean dosages (sd) were significantly different between the ADRB2 genotypes [Arg16Arg 357 µg (326), Arg16Gly 776 µg (449), Gly16Gly 600 µg (443), P=0.036; Gln27Gln 356 µg (254), Gln27Glu 639 µg (354), Glu27Glu 577 µg (388), P=0.007]. Multiple linear regression analysis revealed that age, male gender, rostral extent of sensory block, lower arterial pressure before TEA, and ADRB2 Glu27 allele together explained 37% of phenylephrine dosage variation, with genetic variants being the second most important predictor (10%; P<0.001). CONCLUSIONS: The ADRB2 Glu27 allele is an independent predictor of arterial hypotension and vasopressor requirements after TEA. Neural block can unmask genetic influences on neurohumoral regulation. Clinical trial registration DRKS00005260.

Active atmosphere-ecosystem exchange of the vast majority of detected volatile organic compounds.

Numerous volatile organic compounds (VOCs) exist in Earth's atmosphere, most of which originate from biogenic emissions. Despite VOCs' critical role in tropospheric chemistry, studies for evaluating their atmosphere-ecosystem exchange (emission and deposition) have been limited to a few dominant compounds owing to a lack of appropriate measurement techniques. Using a high-mass resolution proton transfer reaction-time of flight-mass spectrometer and an absolute value eddy-covariance method, we directly measured 186 organic ions with net deposition, and 494 that have bidirectional flux. This observation of active atmosphere-ecosystem exchange of the vast majority of detected VOCs poses a challenge to current emission, air quality, and global climate models, which do not account for this extremely large range of compounds. This observation also provides new insight for understanding the atmospheric VOC budget.

Topical Yunnan Baiyao administration as an adjunctive therapy for bleeding complications in adolescents with advanced cancer.

PURPOSE: Yunnan Baiyao (White Medicine from Yunnan, YNB) is a Chinese herbal medicinal powder used to stop bleeding and improve circulation in traumatic injuries. We describe the use of YNB in adolescents with cancer as an adjunct to uncontrolled bleeding in the palliative care setting. METHODS: Through a retrospective chart review of all patients receiving integrative medicine consultations at the Integrative Therapies Program at Columbia University from January 1, 2007 to January 31, 2012, we describe the outcome of patients treated with YNB for management of uncontrolled bleeding. RESULTS: Four patients were identified who received topical YNB for uncontrolled bleeding; patients included two males and two females with diagnoses of solid tumors (n = 3) and Burkitt's lymphoma (n = 1). Mean age was 15.5 years (range 15-17). Fifty percent had life-threatening bleeding from the tumor site and 50 % experienced uncontrollable epistaxis. All patients received preceding therapy with packed red blood cells and platelet transfusions, topical thrombin, and oral aminocaproic acid. Two patients used YNB in the inpatient setting, and all four patients used YNB as outpatients. In all patients, bleeding control improved with the addition of YNB to conventional hemostatic interventions. Two patients using YNB in their home reported control of bleeding episodes. There were no adverse events reported. CONCLUSIONS: YNB may be an efficacious agent for uncontrolled bleeding in conjunction with conventional hemostatic agents in adolescents with advanced cancer. It is well accepted by patients. YNB may be especially valuable in the outpatient setting to prevent the recurrence of hemorrhage.