Broadband two-dimensional electronic spectroscopy in an actively phase stabilized pump-probe configuration.

We introduce a novel configuration for two-dimensional electronic spectroscopy (2DES) that combines the partially collinear pump-probe geometry with active phase locking. We demonstrate the method on a solution sample of CdSe/ZnS nanocrystals by employing two non-collinear optical parametric amplifiers as the pump and probe sources. The two collinear pump pulse replicas are created using a Mach-Zehnder interferometer phase stabilized by active feedback electronics. Taking the advantage of separated paths of the two pump pulses in the interferometer, we improve the signal-to-noise ratio with double modulation of the individual pump beams. In addition, a quartz wedge pair manipulates the phase difference between the two pump pulses, enabling the recovery of the rephasing and non-rephasing signals. Our setup integrates many advantages of available 2DES techniques with robust phase stabilization, ultrafast time resolution, two-color operation, long delay scan, individual polarization manipulation and the ease of implementation.

Vericiguat protects against cardiac damage in a pig model of ischemia/reperfusion.

BACKGROUND: The purpose of this research was to verify that vericiguat, a soluble guanylate cyclase (sGC) stimulator, reduces myocardial ischemic reperfusion injury (MIRI), and to learn how this reduction happens. METHODS AND RESULTS: To develop an ischaemia/reperfusion (I/R) model, the left anterior descending artery was blocked in minipigs under anesthesia for 90 minutes, followed by 180 minutes of reperfusion. Vericiguat is administered three hours before surgery. Two weeks after receiving therapy, pigs underwent cardiovascular magnetic resonance imaging (MRI) to evaluate the results. The MRI results suggest improvement in the myocardial infarct after vericiguat treatment. Vericiguat treatment for two weeks enhanced vascularity, inhibited pro-inflammatory cells, and decreased collagen deposition in the infarct zone of pigs. Short-term experiments investigating possible explanations have indicated that vericiguat has antiapoptotic effects on cardiomyocytes and increases levels of autophagy. CONCLUSIONS: Vericiguat, an SGC activator, reduces MIRI in pigs by boosting autophagy, preventing apoptosis, and promoting angiogenesis.

Longer leukocyte telomere length increases cardiovascular mortality in type 2 diabetes patients.

AIMS: Leukocyte telomere length (LTL), as a biomarker of biological aging, is associated with the prevalence and complications of diabetes. This study aims to investigate the associations between LTL and all-cause and cause-specific mortality in patients with type 2 diabetes. METHODS: All participants with baseline LTL records were included from the National Health and Nutrition Examination Survey 1999-2002. Death status and its causes were ascertained for National Death Index based on International Classification of Diseases, Tenth Revision code. Cox proportional hazards regression models were established to estimate the hazard ratios (HRs) of LTL associating with all-cause and cause-specific mortality. RESULTS: The study enrolled 804 diabetic patients with the mean follow-up of 14.9 ± 2.59 years. There were 367 (45.6%) all-cause deaths, 80 (10.0%) cardiovascular deaths, and 42 (5.2%) cancer-related deaths. Longer LTL was associated with reduced all-cause mortality, whereas this association disappeared after adjusting for other variables. Compared with the lowest tertiles of LTL, the multivariable-adjusted hazard ratio of cardiovascular mortality was 2.11 (95% confidence interval [CI] 1.31-3.39; p < .05) in the highest tertiles. In terms of cancer mortality, the highest tertile was negatively correlated with the risk of cancer mortality (HR 0.58 [95% CI 0.37, 0.91], p < .05). CONCLUSION: In conclusion, LTL was independently associated with the risk of cardiovascular mortality in patients with type 2 diabetes and was negatively correlated with the risk of cancer mortality. Telomere length may be a predictor of cardiovascular mortality in diabetes.

A dual-responsive ratiometric indicator designed for in vivo monitoring of oxidative stress and antioxidant capacity.

The imbalance between oxidative stress and antioxidant capacity is strongly associated with the development of numerous degenerative diseases, including cardiovascular diseases, diabetes, neurodegenerative diseases, and cancer. Therefore, monitoring oxidative stress and antioxidant capacity in vivo is crucial for maintaining cellular homeostasis and the stability of the organism's internal environment. Here, we present the findings of our study on DQ1, a dual-responsive indicator designed specifically for imaging H2O2 and NAD(P)H, which are critical indicators of oxidative stress and antioxidant capacity. DQ1 facilitated the colorimetric and fluorescence detection of H2O2 and NAD(P)H in two well-separated channels, exhibiting a detection limit of 1.0 µM for H2O2 and 0.21 nM for NAD(P)H, respectively. Experiments conducted on living cells and zebrafish demonstrated that DQ1 could effectively detect changes in H2O2 and NAD(P)H levels when exposed to exogenous hypoxic conditions and chemical stimuli. Furthermore, the effectiveness of the as-fabricated indicator was investigated in two distinct mouse models: evaluating H2O2 and NAD(P)H levels in myocardial cell dysfunction during acute myocardial infarction and liver tissue damage under trichloroethylene stress conditions. In vivo experiments demonstrated that the levels of the two cardiac biomarkers increase progressively with the development of myocardial infarction, eventually reaching a steady state after 7 days when the damaged cells in the infarcted region become depleted. Moreover, during 14 continuous days of exposure to trichloroethylene, the two biomarkers in liver tissue exhibited a sustained increase, indicating a significant enhancement in intracellular oxidative stress and antioxidant capacity attributed to the mouse liver's robust metabolic capacity. The aforementioned studies underscore the efficacy of DQ1 as a valuable tool for scrutinizing redox states at both the single-cell and biological tissue levels. It presents significant potential for investigating the dynamic alternations in oxidative stress and antioxidant capacity within disease models as the disease progresses, thereby facilitating a more profound comprehension of these processes across various disease models.

Coherent optical phonon oscillation and possible electronic softening in WTe2 crystals.

A rapidly-growing interest in WTe2 has been triggered by the giant magnetoresistance effect discovered in this unique system. While many efforts have been made towards uncovering the electron- and spin-relevant mechanisms, the role of lattice vibration remains poorly understood. Here, we study the coherent vibrational dynamics in WTe2 crystals by using ultrafast pump-probe spectroscopy. The oscillation signal in time domain in WTe2 has been ascribed as due to the coherent dynamics of the lowest energy A1 optical phonons with polarization- and wavelength-dependent measurements. With increasing temperature, the phonon energy decreases due to anharmonic decay of the optical phonons into acoustic phonons. Moreover, a significant drop (15%) of the phonon energy with increasing pump power is observed which is possibly caused by the lattice anharmonicity induced by electronic excitation and phonon-phonon interaction.