Sudden cardiac arrest (CA) is a leading cause of death worldwide. Breathing nitric oxide (NO) reduces ischemia/reperfusion injury in animal models and in patients. The objective of this study was to ...learn whether inhaled NO improves outcomes after CA and cardiopulmonary resuscitation (CPR).
Adult male mice were subjected to potassium-induced CA for 7.5 minutes whereupon CPR was performed with chest compression and mechanical ventilation. One hour after CPR, mice were extubated and breathed air alone or air supplemented with 40 ppm NO for 23 hours. Mice that were subjected to CA/CPR and breathed air exhibited a poor 10-day survival rate (4 of 13), depressed neurological and left ventricular function, and increased caspase-3 activation and inflammatory cytokine induction in the brain. Magnetic resonance imaging revealed brain regions with marked water diffusion abnormality 24 hours after CA/CPR in mice that breathed air. Breathing air supplemented with NO for 23 hours starting 1 hour after CPR attenuated neurological and left ventricular dysfunction 4 days after CA/CPR and markedly improved 10-day survival rate (11 of 13; P=0.003 versus mice breathing air). The protective effects of inhaled NO on the outcome after CA/CPR were associated with reduced water diffusion abnormality, caspase-3 activation, and cytokine induction in the brain and increased serum nitrate/nitrite levels. Deficiency of the α1 subunit of soluble guanylate cyclase, a primary target of NO, abrogated the ability of inhaled NO to improve outcomes after CA/CPR.
These results suggest that NO inhalation after CA and successful CPR improves outcome via soluble guanylate cyclase-dependent mechanisms.
Overview of Pituitary Surgery Fang, Christina H; Agarwal, Vijay; Liu, James K ...
Otolaryngologic clinics of North America
55, Številka:
2
Journal Article
Recenzirano
Management of patients with pituitary lesions is complex given the delicate nature of the surrounding anatomy and complexity of underlying disease. The care of these patients ideally involves a ...multidisciplinary team composed of endocrinologists, neuroradiologists, otolaryngologists, neurosurgeons, critical care physicians, and anesthesiologists. The endoscopic endonasal approach to the skull base has revolutionized pituitary and anterior skull base surgery and has gained popularity worldwide. This article presents an overview of the diagnosis, work-up, and management of patients with pituitary lesions, with an emphasis on surgical, perioperative, and postoperative considerations.
ABSTRACT
We report on the the long term monitoring campaign of the seemingly youngest magnetar Swift J1818.0–1607 at radio and X-ray wavelengths over a span of one year. We obtained a coherent timing ...solution for the magnetar over the same time span. The frequency derivative of the magnetar shows systematic variation with the values oscillating about a mean value of −1.37 × 10−11 Hz s−1. The magnitude of the variation in the frequency derivative reduces with time before converging on the mean value. This corresponds to a characteristic age of ∼ 860 years, 2–4 times more than previously estimated. We were able to identify four states in the spin-frequency derivative that were quantified by the amount of modulation about the mean value and the transition between these states seem to be correlated with the change in the radio emission of the magnetar while no correlation is seen in the average radio profile variability on a shorter time-scale (days). The 0.5–12 keV X-ray flux shows a monotonic decrease that can be attributed to thermal emission from a hot spot on the surface of the neutron star that is reducing in size. Such decrease is consistent with what is seen in other magnetars. The potential correlation between the radio emission mode and the behaviour of the spin-down rate hints to a global change in the magnetopshere of the magnetar akin to the correlation seen in a subset of mode-changing radio pulsars and suggests a physical link between the two sub-populations.
ABSTRACT Two-ribbon brightenings are one of the most remarkable characteristics of an eruptive solar flare and are often used to predict the occurrence of coronal mass ejections (CMEs). Nevertheless, ...it was recently called into question whether all two-ribbon flares are eruptive. In this paper, we investigate a two-ribbon-like white-light (WL) flare that is associated with a failed magnetic flux rope (MFR) eruption on 2015 January 13, which has no accompanying CME in the WL coronagraph. Observations by the Optical and Near-infrared Solar Eruption Tracer and the Solar Dynamics Observatory reveal that with the increase of the flare emission and the acceleration of the unsuccessfully erupting MFR, two isolated kernels appear at the WL 3600 passband and quickly develop into two elongated ribbon-like structures. The evolution of the WL continuum enhancement is completely coincident in time with the variation of Fermi hard X-ray 26-50 keV flux. An increase of continuum emission is also clearly visible at the whole FUV and NUV passbands observed by the Interface Region Imaging Spectrograph. Moreover, in one WL kernel, the Si iv, C ii, and Mg ii h/k lines display significant enhancement and non-thermal broadening. However, their Doppler velocity pattern is location-dependent. At the strongly bright pixels, these lines exhibit a blueshift, while at moderately bright ones, the lines are generally redshifted. These results show that the failed MFR eruption is also able to produce a two-ribbon flare and high-energy electrons that heat the lower atmosphere, causing the enhancement of the WL and FUV/NUV continuum emissions and chromospheric evaporation.
Infectious diseases seriously threaten human health. The early detection of the causative organism and antibiotic resistance genes of infection remains a major clinical challenge. Next-generation ...sequencing has been widely used in diagnosing infectious diseases. Cheaper and faster targeted next-generation sequencing technology is progressively being used in clinical practice. However, the awareness among clinicians about the clinical utility of this technology is limited. The article presents the theoretical background, advantages and disadvantages, clinical applications of targeted next-generation sequencing, and its contrasts with metagenomics next-generation sequencing. It provides a reference for clinicians to select laboratory methods for identifying pathogens in clinical practice.
With the pervasive presence of massive smart devices, Internet of Things (IoT) is enabled by wireless communication technology. The devices in IoT usually have very diverse bandwidth capabilities and ...thus in need of many communication standards. To facilitate communications between these heterogeneous bandwidths of devices, middlewares have often been developed. However, they are often not suitable for resource-constrained scenario due to their complexity. It leads us to ask is there a unified approach that can support the communication between the devices with heterogeneous bandwidths? In this paper, we propose the time-reversal (TR) approach to answer such a question. A novel TR-based heterogeneous system is proposed, which can address the bandwidth heterogeneity and maintain the benefit of TR at the same time. Although there is an increase in complexity, it concentrates mostly on the digital processing of the access point (AP), which can be easily handled with more powerful digital signal processor (DSP). Since there is no middleware in the proposed system and the additional physical layer complexity concentrates on the AP side, the proposed TR approach better satisfies the requirement of low complexity and energy efficiency for terminal devices (TDs). We further conduct the theoretical analysis of the interference in the proposed system. Simulations show the bit-error-rate (BER) performance can be significantly improved with appropriate spectrum allocation. Finally, Smart Homes is chosen as an example of IoT applications to evaluate the performance of the proposed system.
Due to the unique spatial and temporal focusing effects, time-reversal (TR) communication can be utilized in the cloud radio access network (C-RAN), where it creates "tunneling effects" such that the ...traffic load in the front-haul links can be alleviated in both downlink and uplink. Although the basic TR waveforms are simple to use, and they cannot provide the optimal performance in some cases. Since the C-RAN is usually expected to serve massive wireless devices, the severe inter-user interference will limit the performance of the system, especially in the high signal-to-noise ratio region where the interference power dominates the noise power. In this paper, we propose to optimize both downlink and uplink transmissions in the TR-based C-RAN so as to alleviate the interference. In the downlink transmission, an optimal content-aware waveform design is proposed, so that the baseband units (BBUs) are able to combine both the channel information and the content information to suppress the interference. In the uplink transmission, an optimal receiver design algorithm is proposed, such that the BBUs can detect the symbols transmitted by the terminal devices more accurately by leveraging the channel information. We study the bit error rate performance of the proposed algorithms based on extensive measurements of the wireless channel in a real-world environment. Numerical results demonstrate the significant performance improvement over the basic TR transmission techniques and the traditional waveform design techniques.
The angiostatic nature of pharmacological doses of glucocorticoid steroids is well known. However, the consequences of pathophysiological elevation of endogenous glucocorticoids are not well ...established. In the current study, we hypothesized that the angiostatic effect of corticosterone, an endogenous glucocorticoid in rodents, occurs through multi-faceted alterations in skeletal muscle microvascular endothelial cell proliferation, migration, and proteolysis. Chronic corticosterone treatment significantly reduced the capillary to fiber ratio in the tibialis anterior muscle compared to that of placebo-treated rats. Corticosterone inhibited endothelial cell sprouting from capillary segments ex vivo. Similarly, 3-dimensional endothelial cell spheroids treated with corticosterone for 48 hours showed evidence of sprout regression and reduced sprout length. Endothelial cell proliferation was reduced in corticosterone treated cells, coinciding with elevated FoxO1 and reduced VEGF production. Corticosterone treated endothelial cells exhibited reduced migration, which correlated with a reduction in RhoA activity. Furthermore, corticosterone treated endothelial cells in both 3-dimensional and monolayer cultures had decreased MMP-2 production and activation resulting in decreased proteolysis by endothelial cells, limiting their angiogenic potential. Promoter assays revealed that corticosterone treatment transcriptionally repressed MMP-2, which may map to a predicted GRE between -1510 and -1386 bp of the MMP-2 promoter. Additionally, Sp1, a known transcriptional activator of MMP-2 was decreased following corticosterone treatment. This study provides new insights into the mechanisms by which pathophysiological levels of endogenous glucocorticoids may exert angiostatic effects.
PDF
