Doing without water: The 18F labeling of radiopharmaceuticals requires nearly anhydrous solutions of 18Ffluoride. Aqueous K2CO3 is generally used to elute 18Ffluoride from an anion‐exchange resin. ...Replacing aqueous K2CO3 with strong organic bases, such as the phosphazene base P2Et (conjugate acid shown), enabled the recovery of highly reactive 18Ffluoride and avoided the azeotropic evaporation of water, which is very difficult on a microchip device.
Purpose
Previous clinical trials suggested that inhaled nitric oxide (iNO) could have beneficial effects in sickle cell disease (SCD) patients with acute chest syndrome (ACS).
Methods
To determine ...whether iNO reduces treatment failure rate in adult patients with ACS, we conducted a prospective, double-blind, randomized, placebo-controlled clinical trial. iNO (80 ppm,
N
= 50) gas or inhaled nitrogen placebo (
N
= 50) was delivered for 3 days. The primary end point was the number of patients with treatment failure at day 3, defined as any one of the following: (1) death from any cause, (2) need for endotracheal intubation, (3) decrease of PaO
2
/FiO
2
≥ 15 mmHg between days 1 and 3, (4) augmented therapy defined as new transfusion or phlebotomy.
Results
The two groups did not differ in age, gender, genotype, or baseline characteristics and biological parameters. iNO was well tolerated, although a transient decrease in nitric oxide concentration was mandated in one patient. There was no significant difference in the primary end point between the iNO and placebo groups 23 (46 %) and 29 (58 %); odds ratio (OR), 0.8; 95 % CI, 0.54–1.16;
p
= 0.23. A post hoc analysis of the 45 patients with hypoxemia showed that those in the iNO group were less likely to experience treatment failure at day 3 7 (33.3 %) vs 18 (72 %); OR = 0.19; 95 % CI, 0.06–0.68;
p
= 0.009.
Conclusions
iNO did not reduce the rate of treatment failure in adult SCD patients with mild to moderate ACS. Future trials should target more severely ill ACS patients with hypoxemia.
Clinical trial registration
NCT00748423.
Invasive life-support techniques are a major risk factor for nosocomial infection. Noninvasive ventilation (NIV) can be used to avoid endotracheal intubation and may reduce morbidity among patients ...in intensive care units (ICUs).
To determine whether the use of NIV is associated with decreased risk of nosocomial infections and improved survival in everyday clinical practice among patients with acute exacerbation of chronic obstructive pulmonary disease (COPD) or hypercapnic cardiogenic pulmonary edema (CPE).
Matched case-control study conducted in the medical ICU of a French university hospital from January 1996 through March 1998.
Fifty patients with acute exacerbation of COPD or severe CPE who were treated with NIV for at least 2 hours and 50 patients treated with mechanical ventilation between 1993 and 1998 (controls), matched on diagnosis, Simplified Acute Physiology Score II, Logistic Organ Dysfunction score, age, and no contraindication to NIV.
Rates of nosocomial infections, antibiotic use, lengths of ventilatory support and of ICU stay, ICU mortality, compared between cases and controls.
Rates of nosocomial infections and of nosocomial pneumonia were significantly lower in patients who received NIV than those treated with mechanical ventilation (18% vs 60% and 8% vs 22%; P<.001 and P =.04, respectively). Similarly, the daily risk of acquiring an infection (19 vs 39 episodes per 1000 patient-days; P =.05), proportion of patients receiving antibiotics for nosocomial infection (8% vs 26%; P =.01), mean (SD) duration of ventilation (6 6 vs 10 12 days; P =.01), mean (SD) length of ICU stay (9 7 vs 15 14 days; P =.02), and crude mortality (4% vs 26%; P =.002) were all lower among patients who received NIV than those treated with mechanical ventilation.
Use of NIV instead of mechanical ventilation is associated with a lower risk of nosocomial infections, less antibiotic use, shorter length of ICU stay, and lower mortality. JAMA. 2000;284:2361-2367.
The mechanism of plasmapause formation based on interchange instability and a Kp‐dependent magnetospheric electric field model, enables us to determine the position of the plasmapause as a function ...of Kp and local time. We illustrate here how this physical mechanism is able to account for the formation of shoulders like those observed by EUV on IMAGE. A wide variety of other structures observed by IMAGE like tails (also called plumes), and notches are also obtained with this mechanism for the formation of a “knee” in the high altitude cross‐L distribution of the cold plasma density distribution.
Intensive care unit (ICU) caregivers should seek to develop collaborative relationships with their patients' family members, based on an open exchange of information and aimed at helping family ...members cope with their distress and allowing them to speak for the patient if necessary. We conducted a prospective multicenter study of family member satisfaction evaluated using the Critical Care Family Needs Inventory. Forty-three French ICUs participated in the study. ICU characteristics, patient and family member demographics, and data on satisfaction were collected. Factors associated with satisfaction were identified using a Poisson regression model. A total of 637 patients were included in the study, and 920 family members completed the questionnaire. Seven predictors of family satisfaction were found: one family-related factor, namely, family of French descent and six caregiver-related factors, namely, no perceived contradictions in information given by caregivers; information provided by a junior physician; patient to nurse ratio </= 3; knowledge of the specific role of each caregiver; help from the family's own doctor; and sufficient time spent giving information. Predictors of satisfaction are amenable to intervention and deserve to be investigated further with the goal of improving the satisfaction of ICU patients' family members.
Pulse oximetry (SpO2) is a standard monitoring device in intensive care units (ICUs), currently used to guide therapeutic interventions. Few studies have evaluated the accuracy of SpO2 in critically ...ill patients. Our objective was to compare pulse oximetry with arterial oxygen saturation (SaO2) in such patients, and to examine the effect of several factors on this relationship.
Observational prospective study.
A 26-bed medical ICU in a university hospital.
One hundred two consecutive patients admitted to the ICU in whom one or serial arterial blood gas analyses (ABGs) were performed and a reliable pulse oximeter signal was present.
For each ABG, we collected SaO2, SpO2, the type of pulse oximeter, the mode of ventilation and requirement for vasoactive drugs.
Three hundred twenty-three data points were collected. The mean difference between SpO2 and SaO2 was -0.02% and standard deviation of the differences was 2.1%. From one sample to another, the fluctuations in SpO2 to arterial saturation difference indicated that SaO2 could not be reliably predicted from SpO2 after a single ABG. Subgroup analysis showed that the accuracy of SpO2 appeared to be influenced by the type of oximeter, the presence of hypoxemia and the requirement for vasoactive drugs. Finally, high SpO2 thresholds were necessary to detect significant hypoxemia with good sensitivity.
Large SpO2 to SaO2 differences may occur in critically ill patients with poor reproducibility of SpO2. A SpO2 above 94% appears necessary to ensure a SaO2 of 90%.
Small supernumerary marker chromosomes (sSMCs) are structurally abnormal chromosomes that cannot be characterized by karyotype. In many prenatal cases of de novo sSMC, the outcome of pregnancy is ...difficult to predict because the euchromatin content is unclear. This study aimed to determine the presence or absence of euchromatin material of 39 de novo prenatally ascertained sSMC by array‐comparative genomic hybridization (array‐CGH) or single nucleotide polymorphism (SNP) array. Cases were prospectively ascertained from the study of 65,000 prenatal samples 0.060%; 95% confidence interval (CI), 0.042–0.082. Array‐CGH showed that 22 markers were derived from non‐acrocentric markers (56.4%) and 7 from acrocentic markers (18%). The 10 additional cases remained unidentified (25.6%), but 7 of 10 could be further identified using fluorescence in situ hybridization; 69% of de novo sSMC contained euchromatin material, 95.4% of which for non‐acrocentric markers. Some sSMC containing euchromatin had a normal phenotype (31% for non‐acrocentric and 75% for acrocentric markers). Statistical differences between normal and abnormal phenotypes were shown for the size of the euchromatin material (more or less than 1 Mb, p = 0.0006) and number of genes (more or less than 10, p = 0.0009). This study is the largest to date and shows the utility of array‐CGH or SNP array in the detection and characterization of de novo sSMC in a prenatal context.
This paper is a follow up of the article where Lemaire and Stegen (Solar Phys.
291
(12), 3659,
2016
) introduced their DYN method to calculate coronal temperature profiles from given radial ...distributions of the coronal and solar wind (SW) electron densities. Several such temperature profiles are calculated and presented corresponding to a set of given empirical density models derived from eclipse observations and in-situ measurements of the electron density and bulk velocity at 1 AU. The DYN temperature profiles obtained for the equatorial and polar regions of the corona challenge the results deduced since 1958 from singular hydrodynamical models of the SW. In these models—where the expansion velocity transits through a singular saddle point—the maximum coronal temperature is predicted to be located at the base of the corona, while in all DYN models the altitude of the maximum temperature is found at significantly higher altitudes in the mid-corona. Furthermore, the maximum of the DYN-estimated temperatures is found at much higher altitudes over the polar regions and coronal holes, than over the equator. However, at low altitudes, in the inner corona, the DYN temperatures are always smaller at high latitudes, than at low equatorial latitudes. This appears well in agreement with existing coronal hole observations. These findings have serious implications on the open questions: what is the actual source of the coronal heating, and where is the maximum energy deposited within the solar corona?
The most used method to calculate the coronal electron temperature
T
e
(
r
)
from a coronal density distribution
n
e
(
r
)
is the scale-height method (SHM). We introduce a novel method that is a ...generalization of a method introduced by Alfvén (
Ark. Mat. Astron. Fys.
27
, 1,
1941
) to calculate
T
e
(
r
)
for a corona in hydrostatic equilibrium: the “HST” method. All of the methods discussed here require given electron-density distributions
n
e
(
r
)
which can be derived from white-light (WL) eclipse observations. The new “DYN” method determines the unique solution of
T
e
(
r
)
for which
T
e
(
r
→
∞
)
→
0
when the solar corona expands radially as realized in hydrodynamical solar-wind models. The applications of the SHM method and DYN method give comparable distributions for
T
e
(
r
)
. Both have a maximum
T
max
whose value ranges between 1 – 3 MK. However, the peak of temperature is located at a different altitude in both cases. Close to the Sun where the expansion velocity is subsonic (
r
<
1.3
R
⊙
) the DYN method gives the same results as the HST method. The effects of the other free parameters on the DYN temperature distribution are presented in the last part of this study. Our DYN method is a new tool to evaluate the range of altitudes where the heating rate is maximum in the solar corona when the electron-density distribution is obtained from WL coronal observations.
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