A Real-World Comparative Effectiveness Analysis of Thromboprophylactic Use of Enoxaparin Versus Unfractionated Heparin in Abdominal Surgery Patients in a Large U.S. Hospital Database

Introduction: Little is known about outcomes associated with enoxaparin versus unfractionated heparin (UFH) for venous thromboembolism (VTE) prophylaxis in abdominal surgery patients in U.S. clinical practice. The purpose of this study was to compare VTE, all-cause mortality, PE-related in-hospital mortality, and hospital costs during abdominal surgery hospitalization and the 90 days post-discharge between patients who received enoxaparin versus UFH prophylaxis. Materials and Methods: Using the Premier Healthcare Database, abdominal surgery patients who received at least 1 day of VTE prophylaxis with enoxaparin or UFH were identified between January 1, 2010 and September 30, 2016. Clinical outcomes were assessed using multivariable logistic regression models and cost outcomes were assessed using generalized linear models. Results: Of 363,669 patients identified, 59% received enoxaparin and 41% UFH. In adjusted analyses, there were statistically significant lower odds of VTE (OR 0.80; 95% CI 0.65-0.97), all-cause mortality (OR 0.67; 95% CI 0.60-0.75), and major bleeding (OR 0.88; 95% CI 0.82-0.94) during the hospitalization for enoxaparin versus UFH, but no differences during the 90-days post-discharge or for PE-related mortality. There was a statistically significant lower total hospital cost with enoxaparin versus UFH during index hospitalization ($8,913 vs $9,017, P < .0001), but not post-discharge ($3,342 vs $3,368, P = .42). Unadjusted rates of heparin-induced thrombocytopenia (index:0.1% vs 0.3%; post-discharge: 0.02% vs 0.06%) were reported for enoxaparin and UFH, respectively. Conclusion: In contemporary U.S. hospital practice, statistically significant lower odds of VTE, all-cause mortality and major bleeding with enoxaparin versus UFH prophylaxis were found during abdominal surgery hospitalizations.

White Matter Alterations in Spastic Paraplegia Type 5: A Multiparametric Structural MRI Study and Correlations with Biochemical Measurements

BACKGROUND AND PURPOSE

In spastic paraplegia type 5, spinal cord atrophy and white matter signal abnormalities in the brain are the main MR imaging alterations. However, the specific mechanism remains unclear. We explored the microstructural changes occurring in spastic paraplegia type 5 and assessed the relation between MR imaging and clinical data.

MATERIALS AND METHODS

Seventeen patients with spastic paraplegia type 5 and 17 healthy controls were scanned with DTI and T1 mapping on a 3T MR imaging scanner. Fractional anisotropy, mean diffusivity, radial diffusivity, axial diffusivity, and T1 values were obtained using Tract-Based Spatial Statistics and the Spinal Cord Toolbox. Neurofilament light and myelin basic protein in the CSF were measured. The differences in MR imaging and biochemical data between patients with spastic paraplegia type 5 and healthy controls were compared using the Student t test.

RESULTS

A widespread reduction of fractional anisotropy values and an elevation of mean diffusivity, T1, and radial diffusivity values were found in most cervical, T4, and T5 spinal cords; corona radiata; optic radiations; and internal capsules in spastic paraplegia type 5. A variation in axial diffusivity values was shown only in C2, C6, and the corona radiata but not in the gray matter. The levels of neurofilament light and myelin basic protein were higher in those with spastic paraplegia type 5 than in healthy controls (myelin basic protein, 3507 [SD, 2291] versus 127 [SD, 219]  pg/mL; neurofilament light, 617 [SD, 207] versus 265 [SD, 187]  pg/mL; P < .001). No correlation was found between the clinical data and MR imaging-derived measures.

CONCLUSIONS

Multiparametric MR imaging and biochemical indicators demonstrated that demyelination (mainly) and axonal loss led to the white matter integrity loss without gray matter injury in spastic paraplegia type 5.

Elevated thyroid-stimulating hormone levels are associated with poor sleep: a cross-sectional and longitudinal study

PURPOSE

Poor sleep accompanied by elevated TSH (thyroid stimulating hormone) levels is not uncommon since TSH secretion is controlled by the circadian rhythm. However, the relationship between poor sleep and TSH elevation is unclear; hence, we aimed to elucidate this relationship by conducting a cross-sectional and longitudinal study.

METHODS

Participants with isolated elevated (N = 168) and normal (N = 119) TSH concentrations were recruited, and the Pittsburgh Sleep Quality Index (PSQI) was used to assess the sleep status. Subjects with an isolated TSH elevation were followed up longitudinally. The serum TSH concentration was remeasured after sleep status improved.

RESULTS

The proportions of poor sleep and occasional poor sleep in subjects with isolated TSH elevation were significantly higher than those with normal TSH levels (70.24% vs. 49.58%, p = 0.001; 9.52% vs. 1.68%, p = 0.006). Subjects with isolated TSH elevation had significantly higher PSQI scores in the subjective sleep quality, sleep latency, sleep duration, and habitual sleep efficiency dimensions than those with normal TSH levels (all p < 0.05). Poor sleep was significantly associated with isolated TSH elevation in the multiple logistic regression analysis [odds ratio (OR) = 2.396, p = 0.001]. Among subjects with an isolated TSH elevation at baseline, the percentage of TSH normalization was significantly higher in those who slept better than in those who still slept poorly (85.42% vs. 6.45%, p < 0.001).

CONCLUSIONS

This study revealed that isolated elevated TSH concentrations normalize when the sleep status is improved; hence, we recommend that clinicians thoroughly assess the sleep status of patients and remeasure TSH concentrations after sleep status improves.

A Novel Spider Toxin Inhibits Fast Inactivation of the Nav1.9 Channel by Binding to Domain III and Domain IV Voltage Sensors

Venomous animals have evolved to produce peptide toxins that modulate the activity of voltage-gated sodium (Na_v) channels. These specific modulators are powerful probes for investigating the structural and functional features of Na_v channels. Here, we report the isolation and characterization of δ-theraphotoxin-Gr4b (Gr4b), a novel peptide toxin from the venom of the spider Grammostola rosea. Gr4b contains 37-amino acid residues with six cysteines forming three disulfide bonds. Patch-clamp analysis confirmed that Gr4b markedly slows the fast inactivation of Na_v1.9 and inhibits the currents of Na_v1.4 and Na_v1.7, but does not affect Na_v1.8. It was also found that Gr4b significantly shifts the steady-state activation and inactivation curves of Na_v1.9 to the depolarization direction and increases the window current, which is consistent with the change in the ramp current. Furthermore, analysis of Na_v1.9/Na_v1.8 chimeric channels revealed that Gr4b preferentially binds to the voltage-sensor of domain III (DIII VSD) and has additional interactions with the DIV VSD. The site-directed mutagenesis analysis indicated that N1139 and L1143 in DIII S3-S4 linker participate in toxin binding. In sum, this study reports a novel spider peptide toxin that may slow the fast inactivation of Na_v1.9 by binding to the new neurotoxin receptor site-DIII VSD. Taken together, these findings provide insight into the functional role of the Na_v channel DIII VSD in fast inactivation and activation.

Distinct Nutrient Intake Style in Inhabitants of Ultra-High-Altitude Areas in North of Tibet, China: A Cross-Sectional Study Based on Newly Developed Tibetan Food Frequency Questionnaires

Dietary pattern is quite distinct among the inhabitants of high-altitude areas because of environmental and geographical uniqueness; hence, it is important to investigate this data as accurately as possible. However, very few data are related to these populations up to now. Based on the food frequency questionnaire (FFQ) used in the Chinese population, a revised Tibetan edition was developed with respect to the lifestyle in high-altitude areas. After assessment of validity and reproducibility, a nutrition intake survey was conducted among 1,071 randomly sampled Tibetan people. In addition, the Bland-Altman approach was used to compare the agreement between the two dietary tools. For the reproducibility analysis, intraclass correlation coefficients (ICC) were calculated to examine the agreement of food groups and nutrients from the two FFQs (FFQ1 and FFQ2). Nutrient intake was calculated using food composition tables. For the validity analysis, Pearson's correlation of food groups intakes varied from 0.22 to 0.91 (unadjusted). The correlations of nutrients ranged from 0.24 to 0.76 (unadjusted). In the analysis of reliability, the ICC of food groups varied from 0.27 to 0.70 (unadjusted). The ICC of nutrient intakes ranged from 0.22 to 0.87 (unadjusted). The results of nutritional analysis showed that ~25% of foods consumed frequently were traditional Tibetan foods. However, traditional Han foods were frequently consumed. In addition, the energy, iron, and protein intakes for male or female subjects were close to the Chinese Dietary Nutrient Reference Intake (Chinese DRIs); however, fat and sodium intakes were significantly higher than the Chinese DRIs. Interestingly, lower intakes of other types of nutrition, such as vitamin C were detected in people living in high-altitude areas. Our data indicated that excess consumption of fat and sodium and insufficient intake of vitamin C were common among Tibetan people, as compared with the most Chinese people living in the plateau areas. More investigations are needed to reveal the association between the food intake style and high-altitude endemic diseases.

Hyperspectral Estimation of Winter Wheat Leaf Area Index Based on Continuous Wavelet Transform and Fractional Order Differentiation

Leaf area index (LAI) is highly related to crop growth, and the traditional LAI measurement methods are field destructive and unable to be acquired by large-scale, continuous, and real-time means. In this study, fractional order differential and continuous wavelet transform were used to process the canopy hyperspectral reflectance data of winter wheat, the fractional order differential spectral bands and wavelet energy coefficients with more sensitive to LAI changes were screened by correlation analysis, and the optimal subset regression and support vector machine were used to construct the LAI estimation models for different growth stages. The precision evaluation results showed that the LAI estimation models constructed by using wavelet energy coefficients combined with a support vector machine at the jointing stage, fractional order differential combined with support vector machine at the booting stage, and wavelet energy coefficients combined with optimal subset regression at the flowering and filling stages had the best prediction performance. Among these, both flowering and filling stages could be used as the best growth stages for LAI estimation with modeling and validation R2 of 0.87 and 0.71, 0.84 and 0.77, respectively. This study can provide technical reference for LAI estimation of crops based on remote sensing technology.

Spastic paraplegia as the only manifestation in neuropsychiatric lupus: a case report

Demyelination syndrome is one manifestation of neuropsychiatric lupus erythematosus (NPLE) and is rare in systemic lupus erythematosus (SLE). When SLE presents only neuropsychiatric symptoms without damage to other systems, its diagnosis becomes difficult. Herein, we report a 29-year-old male who suffered from lower limb stiffness with recessive onset and progressive aggravation in one year. He had paraplegia, spastic hypertonia, abnormal gait, and bilateral positive Babinski signs. His symptoms indicated spastic paraplegia. Brain MRI showed multiple small demyelinating lesions in the lateral ventricle, brainstem, and cerebellum. Anti-ds DNA, anti-Sm and anti-RNP antibodies were positive. He was diagnosed with NPLE and had a good treatment response to steroids. To the best of our knowledge, this is the first case of spastic paraplegia as the only manifestation in SLE.

Schisandrin B Attenuates Airway Inflammation and Airway Remodeling in Asthma by Inhibiting NLRP3 Inflammasome Activation and Reducing Pyroptosis

Asthma is a chronic inflammatory disorder of the airways. Schisandrin B (SB) is the main effective component. This study investigated the effects of SB on airway inflammation and airway remodeling in asthma. The rat model of asthma was established. The rats were treated with SB to evaluate the effects of SB on airway inflammation, airway remodeling, NLRP3 inflammasome activation, and pyroptosis. Alveolar macrophages of rats were isolated, and the macrophage inflammatory model was established by lipopolysaccharide (LPS) induction. The LPS-induced macrophages were treated with SB. The binding relationship between miR-135a-5p and TPRC1 was analyzed. LPS + SB-treated macrophages were transfected with miR-135a-5p inhibitor. The expressions of key factors of the STAT3/NF-κB pathway were detected. SB reduced airway inflammation and airway remodeling in asthmatic rats. SB inhibited NLRP3 inflammasome activation and reduced pyroptosis in asthmatic rats and LPS-induced macrophages. SB reversely regulated the miR-135a-5p/TRPC1 axis. Downregulation of miR-135a-5p attenuated the inhibitory effect of SB on NLRP3 inflammasome activation. SB inhibited the STAT3/NF-κB pathway via the miR-135a-5p/TRPC1 axis. In conclusion, SB inhibited NLRP3 inflammasome activation and reduced pyroptosis via the miR-135a-5p/TRPC1/STAT3/NF-κB axis, thus alleviating airway inflammation and airway remodeling in asthma. This study may confer novel insights for the management of asthma.

Effective inhibition of coronavirus replication by Polygonum cuspidatum

Background: The coronavirus disease 2019 pandemic, caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has infected more than 210 million individuals globally and resulted in over 4 million deaths since the first report in December 2019. The early use of traditional Chinese medicine (TCM) for light and ordinary patients, can rapidly improve symptoms, shorten hospitalization days and reduce severe cases transformed from light and normal. Many TCM formulas and products have a wide application in treating infectious and non-infectious diseases. Polygonum cuspidatum Sieb. et Zucc. (P. cuspidatum), is an important Traditional Chinese Medicine with actions of clearing away heat and eliminating dampness, draining the gallbladder to relieve jaundice, removing blood stasis to alleviate pain, resolving phlegm and arrest cough. In the search for anti-SARS-CoV-2, P. cuspidatum was recommended as as a therapeutic drug of COVID-19 pneumonia.In this study, we aimed to identifies P. cuspidatum is the potential broad-spectrum inhibitor for the treatment of coronaviruses infections. Methods: In the present study , we infected human malignant embryonal rhabdomyoma (RD) cells with the OC43 strain of the coronavirus, which represent an alternative model for SARS-CoV-2 and then employed the cell viability assay kit for the antiviral activity. We combined computer aided virtual screening to predicte the binding site and employed Surface plasmon resonance analysis (SPR) to comfirm the interaction between drugs and coronavirus. We employed fluorescence resonance energy transfer technology to identify drug's inhibition in the proteolytic activity of 3CLpro and Plpro. Results: Based on our results, polydatin and resveratrol derived from P. cuspidatum significantly suppressed HCoV-OC43 replication. 50% inhibitory concentration (IC₅₀) values of polydatin inhibited SARS-CoV-2 Mpro and Plpro, MERS Mpro and Plpro were 18.66, 125, 14.6 and 25.42 μm, respectively. IC₅₀ values of resveratrol inhibited SARS-CoV-2 Mpro and Plpro, MERS Mpro and Plpro were 29.81 ,60.86, 16.35 and19.04 μM, respectively. Finally, SPR assay confirmed that polydatin and resveratrol had high affinity to SARS-CoV-2, SARS-CoV 3Clpro, MERS-CoV 3Clpro and PLpro protein. Conclusions: we identified the antiviral activity of flavonoids polydatin and resveratrol on RD cells. Polydatin and resveratrol were found to be specific and selective inhibitors for SARS-CoV-2, 3CLpro and PLpro, viral cysteine proteases. In summary, this study identifies P. cuspidatum as the potential broad-spectrum inhibitor for the treatment of coronaviruses infections.

The Efficacy of Pyrotinib as a Third- or Higher-Line Treatment in HER2-Positive Metastatic Breast Cancer Patients Exposed to Lapatinib Compared to Lapatinib-Naive Patients: A Real-World Study

Background: Pyrotinib is a novel irreversible pan-ErbB receptor tyrosine kinase inhibitor. Evidence of the efficacy of pyrotinib-based treatments for HER2-positive metastatic breast cancer (MBC) in patients exposed to lapatinib is limited.

Methods: Ninety-four patients who received pyrotinib as a third- or higher-line treatment for HER2-positive MBC were included in this retrospective study. The primary and secondary endpoints were overall survival (OS) and progression‐free survival (PFS). Propensity score matching (PSM) and inverse probability of treatment weighting (IPTW) analysis were implemented to balance important patient characteristics between groups.

Results: Thirty (31.9%) patients were pretreated with lapatinib and subsequently received pyrotinib as an anti-HER2 treatment, and 64 (68.1%) patients did not receive this treatment. The OS and PFS indicated a beneficial trend in lapatinib-naive group compared to lapatinib-treated group in either the original cohort (PFS: 9.02 vs 6.36 months, p = 0.05; OS: 20.73 vs 14.35 months, p = 0.08) or the PSM (PFS: 9.02 vs 6.08 months, p = 0.07; OS: 19.07 vs 18.00 months, p = 0.61) or IPTW (PFS: 9.90 vs 6.17 months, p = 0.05; OS: 19.53 vs 15.10 months, p = 0.08) cohorts. Subgroup analyses demonstrated lapatinib treatment-related differences in PFS in the premenopausal subgroup and the no prior trastuzumab treatment subgroup, but no significant differences were observed in OS.

Conclusion: Pyrotinib-based therapy demonstrated promising effects in HER2-positive MBC patients in a real-world study, especially in lapatinib-naive patients, and also some activity in lapatinib-treated patients.

Supercritical CO2 Synthesis of Freestanding Se1-x S x Foamy Cathodes for High-Performance Li-Se1-x S x Battery

Selenium-sulfur solid solutions (Se_1-x S _x ) are considered to be a new class of promising cathodic materials for high-performance rechargeable lithium batteries owing to their superior electric conductivity than S and higher theoretical specific capacity than Se. In this work, high-performance Li-Se_1-x S _x batteries employed freestanding cathodes by encapsulating Se_1-x S _x in a N-doped carbon framework with three-dimensional (3D) interconnected porous structure (NC@SWCNTs) are proposed. Se_1-x S _x is uniformly dispersed in 3D porous carbon matrix with the assistance of supercritical CO₂ (SC-CO₂) technique. Impressively, NC@SWCNTs host not only provides spatial confinement for Se_1-x S _x and efficient physical/chemical adsorption of intermediates, but also offers a highly conductive framework to facilitate ion/electron transport. More importantly, the Se/S ratio of Se_1-x S _x plays an important role on the electrochemical performance of Li- Se_1-x S _x batteries. Benefiting from the rationally designed structure and chemical composition, NC@SWCNTs@Se_0.2S_0.8 cathode exhibits excellent cyclic stability (632 mA h g-1 at 200 cycle at 0.2 A g^-1) and superior rate capability (415 mA h g^-1 at 2.0 A g^-1) in carbonate-based electrolyte. This novel NC@SWCNTs@Se_0.2S_0.8 cathode not only introduces a new strategy to design high-performance cathodes, but also provides a new approach to fabricate freestanding cathodes towards practical applications of high-energy-density rechargeable batteries.

[Communication sound recognition and response modification in the secondary auditory cortex of female mice]

OBJECTIVE

To study the response characteristics of the secondary auditory cortex (A2) to wriggling calls (WC) and the mechanism of response modulation in female mice.

METHODS

We used patch-clamp and immunofluorescence labeling technique to mark and record the action potential and cell type of A2 neurons. Female C57 mice were stimulated with pure tone and white noise (control), 4.5 kHz, 9 kHz, or 13.5 kHz sound waves extracted from WC (single-frequency simulation group), the combinations of every two of the 3 single-frequency sound waves (two-tone frequency simulation group), or the combinations of 4.5 kHz+7.7 kHz+13.5 kHz and 4.5 kHz+9 kHz+13.5 kHz sound waves (three-frequency simulation group). The firing pattern, firing number, threshold, and latency of the action potential of the A2 neurons were recorded in response to the stimulations.

RESULTS

By comparison of the spikes elicited by different sound stimulations, we identified 3 types of neurons with different sensitivities to WC. The WC-sensitive neurons had a significantly greater number of spikes in response to WC than to other sounds and noise (P < 0.001). Comparison of the latency and threshold revealed significantly longer latencies of the WC-sensitive neurons and WC-insensitive neurons in response to WC stimulation than to pure tone stimulation (P=0.002), but their latencies to WC and noise stimulation were similar (P=0.093). The WC-sensitive neurons also had lower threshold to WC than to pure tone and noise stimulations (P=0.02). Analysis of the firing patterns of action potentials showed that the WCsensitive neurons consisted mainly of parvalbumin interneurons. The results of immunofluorescence labeling indicated that inhibitory interneurons were present in the A2 neurons that responded to WC.

CONCLUSION

A2 contains 3 types of neurons with different sensitivities to WC. Among them, the WC-sensitive neurons is mainly PV neurons, whose response characteristics to different types of sounds can help to explain the mechanism of communication sound recognition and response modification in A2.

Silver closed vitrification system versus slow freezing method for the cryopreservation of human ovarian tissue

BACKGROUND

We developed a hand-made silver container as a closed vitrification system (CVS) which avoid bacterial or viral contamination.

OBJECTIVE

The aim of this study was to evaluate the preservation outcomes by comparing silver CVS and slow freezing (SF) method.

MATERIALS AND METHODS

Donated human ovarian tissues were collected from nine patients. The fragments from each patient were randomly and evenly assigned to three groups: fresh control, silver CVS and SF group. The histology of the thawed ovarian tissue was investigated and the levels of secretion of estradiol (E2) and progesterone (P4) in the culture media were used to evaluate the development and function of thawed ovarian tissue.

RESULTS

The results showed that the proportion of morphologically normal primordial follicles was higher in silver CVS group than in SF (P < 0.005). E2 and P4 concentrations were significantly higher in the silver CVS group than in the SF group at any time point after day 6 (E2: P < 0.05; P4: P < 0.05).

CONCLUSION

This study showed that human ovarian tissue cryopreserved with silver CVS had better morphology and higher E2 and P4 levels during in vitro ovarian tissue growth compared with SF. It implies that silver CVS has a better potential for ovarian tissue development in future clinical use.

Magnetic Nanoparticles in Biology and Medicine: Past, Present, and Future Trends

The use of magnetism in medicine has changed dramatically since its first application by the ancient Greeks in 624 BC. Now, by leveraging magnetic nanoparticles, investigators have developed a range of modern applications that use external magnetic fields to manipulate biological systems. Drug delivery systems that incorporate these particles can target therapeutics to specific tissues without the need for biological or chemical cues. Once precisely located within an organism, magnetic nanoparticles can be heated by oscillating magnetic fields, which results in localized inductive heating that can be used for thermal ablation or more subtle cellular manipulation. Biological imaging can also be improved using magnetic nanoparticles as contrast agents; several types of iron oxide nanoparticles are US Food and Drug Administration (FDA)-approved for use in magnetic resonance imaging (MRI) as contrast agents that can improve image resolution and information content. New imaging modalities, such as magnetic particle imaging (MPI), directly detect magnetic nanoparticles within organisms, allowing for background-free imaging of magnetic particle transport and collection. "Lab-on-a-chip" technology benefits from the increased control that magnetic nanoparticles provide over separation, leading to improved cellular separation. Magnetic separation is also becoming important in next-generation immunoassays, in which particles are used to both increase sensitivity and enable multiple analyte detection. More recently, the ability to manipulate material motion with external fields has been applied in magnetically actuated soft robotics that are designed for biomedical interventions. In this review article, the origins of these various areas are introduced, followed by a discussion of current clinical applications, as well as emerging trends in the study and application of these materials.

Variation of Two S3b Residues in KV4.1-4.3 Channels Underlies Their Different Modulations by Spider Toxin κ-LhTx-1

The naturally occurred peptide toxins from animal venoms are valuable pharmacological tools in exploring the structure-function relationships of ion channels. Herein we have identified the peptide toxin κ-LhTx-1 from the venom of spider Pandercetes sp (the Lichen huntsman spider) as a novel selective antagonist of the K_V4 family potassium channels. κ-LhTx-1 is a gating-modifier toxin impeded K_V4 channels' voltage sensor activation, and mutation analysis has confirmed its binding site on channels' S3b region. Interestingly, κ-LhTx-1 differently modulated the gating of K_V4 channels, as revealed by toxin inhibiting K_V4.2/4.3 with much more stronger voltage-dependence than that for K_V4.1. We proposed that κ-LhTx-1 trapped the voltage sensor of K_V4.1 in a much more stable resting state than that for K_V4.2/4.3 and further explored the underlying mechanism. Swapping the non-conserved S3b segments between K_V4.1(₂₈₀FVPK₂₈₃) and K_V4.3(₂₇₅VMTN₂₇₈) fully reversed their voltage-dependence phenotypes in inhibition by κ-LhTx-1, and intensive mutation analysis has identified P282 in K_V4.1, D281 in K_V4.2 and N278 in K_V4.3 being the key residues. Furthermore, the last two residues in this segment of each K_V4 channel (P282/K283 in K_V4.1, T280/D281 in K_V4.2 and T277/N278 in K_V4.3) likely worked synergistically as revealed by our combinatorial mutations analysis. The present study has clarified the molecular basis in K_V4 channels for their different modulations by κ-LhTx-1, which have advanced our understanding on K_V4 channels' structure features. Moreover, κ-LhTx-1 might be useful in developing anti-arrhythmic drugs given its high affinity, high selectivity and unique action mode in interacting with the K_V4.2/4.3 channels.

2D Gadolinium Oxide Nanoplates as T1 Magnetic Resonance Imaging Contrast Agents

Millions of people a year receive magnetic resonance imaging (MRI) contrast agents for the diagnosis of conditions as diverse as fatty liver disease and cancer. Gadolinium chelates, which provide preferred T₁ contrast, are the current standard but face an uncertain future due to increasing concerns about their nephrogenic toxicity as well as poor performance in high-field MRI scanners. Gadolinium-containing nanocrystals are interesting alternatives as they bypass the kidneys and can offer the possibility of both intracellular accumulation and active targeting. Nanocrystal contrast performance is notably limited, however, as their organic coatings block water from close interactions with surface Gadoliniums. Here, these steric barriers to water exchange are minimized through shape engineering of plate-like nanocrystals that possess accessible Gadoliniums at their edges. Sulfonated surface polymers promote second-sphere relaxation processes that contribute remarkable contrast even at the highest fields (r₁ = 32.6 × 10^-3 m Gd^-1 s^-1 at 9.4 T). These noncytotoxic materials release no detectable free Gadolinium even under mild acidic conditions. They preferentially accumulate in the liver of mice with a circulation half-life 50% longer than commercial agents. These features allow these T₁ MRI contrast agents to be applied for the first time to the ex vivo detection of nonalcoholic fatty liver disease in mice.

The SπRIT time projection chamber

The Superconducting Analyzer for MUlti-particles from RAdioIsotope (SAMURAI) Pion-Reconstruction and Ion-Tracker Time Projection Chamber (SπRIT TPC) was designed to enable measurements of heavy ion collisions with the SAMURAI spectrometer at the RIKEN radioactive isotope beam factory and provides constraints on the equation of state of neutron-rich nuclear matter. The SπRIT TPC has a 50.5 cm drift length and an 86.4 × 134.4 cm² pad plane with 12 096 pads that are equipped with the generic electronics for TPCs. The SπRIT TPC allows for an excellent reconstruction of particles and provides isotopic resolution for pions and other light charged particles across a wide range of energy losses and momenta. The details of the SπRIT TPC are presented, along with discussion of the TPC performance based on cosmic rays and charged particles emitted in heavy ion collisions.