Adverse health effects of marijuana use Volkow, Nora D; Compton, Wilson M; Weiss, Susan R B
The New England journal of medicine,
08/2014, Letnik:
371, Številka:
9
Journal Article
Background Stroke, which is a rare but devastating event during pregnancy, occurs in 34 of every 100,000 deliveries; obstetricians are often the first providers to be contacted by symptomatic ...patients. At least one-half of pregnancy-related strokes are likely to be of the ischemic stroke subtype. Most pregnant or newly postpartum women with ischemic stroke do not receive acute stroke reperfusion therapy, although this is the recommended treatment for adults. Little is known about these therapies in pregnant or postpartum women because pregnancy has been an exclusion criterion for all reperfusion trials. Until recently, pregnancy and obstetric delivery were specifically identified as warnings to intravenous alteplase tissue plasminogen activator in Federal Drug Administration labeling. Objective The primary study objective was to compare the characteristics and outcomes of pregnant or postpartum vs nonpregnant women with ischemic stroke who received acute reperfusion therapy. Study Design Pregnant or postpartum (<6 weeks; n = 338) and nonpregnant (n = 24,303) women 18-44 years old with ischemic stroke from 1991 hospitals that participated in the American Heart Association’s Get With the Guidelines–Stroke Registry from 2008-2013 were identified by medical history or International Classification of Diseases, Ninth Revision, codes. Acute stroke reperfusion therapy was defined as intravenous tissue plasminogen activator, catheter-based thrombolysis, or thrombectomy or any combination thereof. A sensitivity analysis was done on patients who received intravenous tissue plasminogen activator monotherapy only. Chi-square tests were used for categoric variables, and Wilcoxon Rank-Sum was used for continuous variables. Conditional logistic regression was used to assess the association of pregnancy with short-term outcomes. Results Baseline characteristics of the pregnant or postpartum vs nonpregnant women with ischemic stroke revealed a younger group who, despite greater stroke severity, were less likely to have a history of hypertension or to arrive via emergency medical services. There were similar rates of acute stroke reperfusion therapy in the pregnant or postpartum vs nonpregnant women (11.8% vs 10.5%; P = .42). Pregnant or postpartum women were less likely to receive intravenous tissue plasminogen activator monotherapy (4.4% vs 7.9%; P = .03), primarily because of pregnancy and recent surgery. There was a trend toward increased symptomatic intracranial hemorrhage in the pregnant or postpartum patients who were treated with tissue plasminogen activator, yet no cases of major systemic bleeding or in-hospital death occurred, and there were similar rates of discharge to home. Data on the timing of pregnancy, which were available in 145 of 338 cases, showed that 44.8% of pregnancy-related strokes were antepartum, that 2.8% occurred during delivery, and that 52.4% were during the postpartum period. Conclusions Using data from the Get With the Guidelines-Stroke Registry to assemble the largest cohort of pregnant or postpartum ischemic stroke patients who had been treated with reperfusion therapy, we observed that pregnant or postpartum women had similarly favorable short-term outcomes and equal rates of total reperfusion therapy to nonpregnant women, despite lower rates of intravenous tissue plasminogen activator use. Future studies should identify the characteristics of pregnant and postpartum ischemic stroke patients who are most likely to safely benefit from reperfusion therapy.
Abstract
We derive cosmological constraints using a galaxy cluster sample selected from the 2500 deg
2
SPT-SZ survey. The sample spans the redshift range 0.25 <
z
< 1.75 and contains 343 clusters ...with SZ detection significance
ξ
> 5. The sample is supplemented with optical weak gravitational lensing measurements of 32 clusters with 0.29 <
z
< 1.13 (from Magellan and
Hubble Space Telescope
) and X-ray measurements of 89 clusters with 0.25 <
z
< 1.75 (from
Chandra
). We rely on minimal modeling assumptions: (i) weak lensing provides an accurate means of measuring halo masses, (ii) the mean SZ and X-ray observables are related to the true halo mass through power-law relations in mass and dimensionless Hubble parameter
E
(
z
) with a priori unknown parameters, and (iii) there is (correlated, lognormal) intrinsic scatter and measurement noise relating these observables to their mean relations. We simultaneously fit for these astrophysical modeling parameters and for cosmology. Assuming a flat
ν
ΛCDM model, in which the sum of neutrino masses is a free parameter, we measure Ω
m
= 0.276 ± 0.047,
σ
8
= 0.781 ± 0.037, and
σ
8
(Ω
m
/0.3)
0.2
= 0.766 ±0.025. The redshift evolutions of the X-ray
Y
X
–mass and
M
gas
–mass relations are both consistent with self-similar evolution to within 1
σ
. The mass slope of the
Y
X
–mass relation shows a 2.3
σ
deviation from self-similarity. Similarly, the mass slope of the
M
gas
–mass relation is steeper than self-similarity at the 2.5
σ
level. In a
νw
CDM cosmology, we measure the dark energy equation-of-state parameter
w
= −1.55 ± 0.41 from the cluster data. We perform a measurement of the growth of structure since redshift
z
∼ 1.7 and find no evidence for tension with the prediction from general relativity. This is the first analysis of the SPT cluster sample that uses direct weak-lensing mass calibration and is a step toward using the much larger weak-lensing data set from DES. We provide updated redshift and mass estimates for the SPT sample.
The adipocyte-derived protein adiponectin is highly heritable and inversely associated with risk of type 2 diabetes mellitus (T2D) and coronary heart disease (CHD). We meta-analyzed 3 genome-wide ...association studies for circulating adiponectin levels (n = 8,531) and sought validation of the lead single nucleotide polymorphisms (SNPs) in 5 additional cohorts (n = 6,202). Five SNPs were genome-wide significant in their relationship with adiponectin (P< or =5x10(-8)). We then tested whether these 5 SNPs were associated with risk of T2D and CHD using a Bonferroni-corrected threshold of P< or =0.011 to declare statistical significance for these disease associations. SNPs at the adiponectin-encoding ADIPOQ locus demonstrated the strongest associations with adiponectin levels (P-combined = 9.2x10(-19) for lead SNP, rs266717, n = 14,733). A novel variant in the ARL15 (ADP-ribosylation factor-like 15) gene was associated with lower circulating levels of adiponectin (rs4311394-G, P-combined = 2.9x10(-8), n = 14,733). This same risk allele at ARL15 was also associated with a higher risk of CHD (odds ratio OR = 1.12, P = 8.5x10(-6), n = 22,421) more nominally, an increased risk of T2D (OR = 1.11, P = 3.2x10(-3), n = 10,128), and several metabolic traits. Expression studies in humans indicated that ARL15 is well-expressed in skeletal muscle. These findings identify a novel protein, ARL15, which influences circulating adiponectin levels and may impact upon CHD risk.
In this article, the temperature of biological tissues is estimated during hyperthermia therapy, while accounting for uncertainties in the bioheat transfer problem and in the available measurements. ...A state estimation problem is solved with the Steady-State Kalman Filter. The Pennes bioheat transfer model and the PRF-Shift Magnetic Resonance Thermometry are used as evolution and observation models, respectively. Instead of using the direct inversion of the measured data as with the PRF-Shift Magnetic Resonance Thermometry, the state-estimation framework allows for enhancing the spatial resolution of the estimated temperature variation and reducing the related uncertainties. Since the time consuming steps of the Steady-State Kalman Filter can be performed offline, the recursive solution of the state estimation problem is performed with computational times smaller than the simulated physical times. Synthetic measurements are used for the state estimation problem in a region of the human forearm, for radiofrequency and laser-diode heat sources of the hyperthermia therapy.
Background Observational studies have reported an association between maternal use of paracetamol in pregnancy and childhood asthma, which was not explained by measured confounding factors. However, ...it is possible that this relation might be confounded by unmeasured behavioural factors linked to paracetamol usage; if that were the case, effects of similar magnitude of partner’s paracetamol use and/or postnatal maternal use would be expected. Methods In the Avon Longitudinal Study of Parents and Children (ALSPAC), a population-based birth cohort, we compared the univariate effects of maternal use of paracetamol in pregnancy on risk of doctor-diagnosed asthma, wheeze and elevated immunoglobulin E (IgE) in the offspring at 7 years of age, with the univariate effects of partner’s use and postnatal maternal use on these phenotypes. Results Maternal use of paracetamol in pregnancy was strongly associated with all outcomes. Partner’s use was very weakly associated with asthma but not associated with wheezing or IgE. Postnatal maternal use was associated with asthma and wheezing, though less strongly than was prenatal use, and was not associated with IgE. On mutual adjustment, the effects of maternal use in pregnancy on all outcomes were not substantially attenuated, whereas the effects of partner’s use on asthma, and of postnatal maternal use on asthma and wheezing, were reduced. Conclusions These findings suggest that the relation between maternal use of paracetamol in pregnancy and childhood asthma is unlikely to be confounded by unmeasured behavioural factors linked to paracetamol use.
Myocardial preconditioning with brief coronary artery occlusions before a sustained ischemic period is reported to reduce infarct size. To determine the number of occlusive episodes required to ...produce the preconditioning effect, we performed single or multiple occlusions of the left circumflex coronary artery (LCx) followed by a sustained occlusion (60 minutes) of the LCx. Anesthetized dogs underwent one (P1), six (P6), or 12 (P12) 5-minute occlusions of the LCx. Each occlusion period was followed by a 10-minute reperfusion period. A 60-minute occlusion of the LCx followed the preconditioning sequences. A control group received a 60-minute occlusion of the LCx without preconditioning. All groups were subjected to 6 hours of reperfusion after which the heart was removed for calculating infarct size (IS), area at risk (AR), and left ventricular mass (LV). The IS/AR ratio for the control group was 29.8 +/- 4.4% (n = 17), which was substantially greater (p less than 0.001) than that of the preconditioned groups: P1, 3.9 +/- 1.3% (n = 14); P6, 0.4 +/- 0.3% (n = 5); and P12, 2.9 +/- 2.8% (n = 5). There were no significant differences in the IS/AR ratio among the three preconditioned groups. The AR/LV ratio was comparable among all groups and did not differ statistically: control, 40.4 +/- 1.3%; P1, 36.2 +/- 1.7%; P6, 36.1 +/- 1.7%; and P12, 37.3 +/- 2.1%. Collateral blood flow to the inner two thirds of the risk region determined with radiolabeled microspheres during ischemia did not differ significantly between the control group (0.03 +/- 0.01 ml/min/g, n = 8) and single occlusion group (0.06 +/- 0.02 ml/min/g, n = 8), indicating that the marked disparity in infarct size could not be attributed to differences in collateral blood flow. The data indicate that preconditioning with one brief ischemic interval is as effective as preconditioning with multiple ischemic periods.
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