Effect of ultrasound-guided stellate ganglion block on cerebral oxygen metabolism and S100B protein during carotid endarterectomy.

OBJECTIVE: To investigate the effect of ultrasound-guided stellate ganglion block (SGB) on cerebral oxygen metabolism and serum S100B during carotid endarterectomy (CEA). METHODS: Patients who were prospectively enrolled to receive CEA under elective general anesthesia were randomized into an SGB group and a control group (ChiCTR2000033385). Before anesthesia, the SGB group underwent ipsilateral SGB under ultrasound guidance, while the control group did not. Ultrasound-guided right subclavian internal jugular vein catheterization was performed under general anesthesia. Mean arterial pressure (MAP) and heart rate (HR) were monitored at various time points (T0-T4). Arterial and internal jugular venous bulb blood were collected for blood gas analysis, determining jugular venous oxygen saturation (SjvO2), arteriovenous oxygen difference (AVDO2), cerebral oxygen extraction ratio (COER), lactate production rate (LPR), and lactate-oxygen index (LOI). The serum concentration of S100B in the internal jugular venous bulb at each time point was measured. RESULTS: The results revealed significantly lower HR during anesthesia induction and surgery in the SGB group, with more stable MAP and HR during endotracheal intubation and surgery compared to the control group (P<0.05). The control group exhibited decreases at T3 and a slight increase at T4. SjvO2 was significantly higher in the SGB group, while AVDO2 and COER gradually decreased over time, but they were significantly higher in the control group (P<0.05). LPR and LOI in both groups peaked at T3 and were significantly different between T4 and T2 (P<0.05). Serum S100B levels in both groups rose and then decreased at each time point, but they were consistently lower in the SGB group (P<0.05). CONCLUSION: SGB before CEA effectively suppresses the stress response, maintains intraoperative hemodynamic stability, improves brain tissue oxygen supply, and demonstrates a neuroprotective effect.

A Practical Method for Blind Pixel Detection for the Push-Broom Thermal-Infrared Hyperspectral Imager.

Thermal infrared hyperspectral imager is one of the frontier payloads in current hyperspectral remote sensing research. It has broad application prospects in land and ocean temperature inversion, environmental monitoring, and other fields. However, due to the influence of the production process of the infrared focal plane array and the characteristics of the material itself, the infrared focal plane array inevitably has blind pixels, resulting in spectral distortion of the data or even invalid data, which limits the application of thermal infrared hyperspectral data. Most of the current blind pixels detection methods are based on the spatial dimension of the image, that is, processing single-band area images. The push-broom thermal infrared hyperspectral imager works completely different from the conventional area array thermal imager, and only one row of data is obtained per scan. Therefore, the current method cannot be directly applied to blind pixels detection of push-broom thermal infrared hyperspectral imagers. Based on the imaging principle of push-broom thermal infrared hyperspectral imager, we propose a practical blind pixels detection method. The method consists of two stages to detect and repair four common types of blind pixels: dead pixel, dark current pixel, blinking pixel, and noise pixel. In the first stage, dead pixels and dark current pixels with a low spectral response rate are detected by spectral filter detection; noise pixels are detected by spatial noise detection; and dark current pixels with a negative response slope are detected by response slope detection. In the second stage, according to the random appearance of blinking pixels, spectral filter detection is used to detect and repair spectral anomalies caused by blinking pixels line by line. In order to verify the effectiveness of the proposed method, a flight test was carried out, using the Airborne Thermal-infrared Hyperspectral Imaging System (ATHIS), the latest thermal infrared imager in China, for data acquisition. The results show that the method proposed in this paper can accurately detect and repair blind pixel, thus effectively eliminating spectral anomalies and significantly improving image quality.

Palladium-catalyzed bisthiolation of terminal alkynes for the assembly of diverse (Z)-1,2-bis(arylthio)alkene derivatives.

An efficient and straightforward palladium-catalyzed three-component cascade bisthiolation of terminal alkynes and arylhydrazines with sodium thiosulfate (Na2S2O3) as the sulfur source for the assembly of functionalized (Z)-1,2-bis(arylthio)alkene derivatives is described. Using 0.5 mol% IPr-Pd-Im-Cl2 as the catalyst, a wide range of terminal alkynes and arylhydrazines are well tolerated, thus producing the desired products in good yields with good functional group tolerance and excellent regioselectivity. Moreover, this protocol could be readily scaled up, showing potential applications in organic synthesis and material science.

Dek40 Encodes a PBAC4 Protein Required for 20S Proteasome Biogenesis and Seed Development.

The 26S proteasome, an essential protease complex of the ubiquitin-26S proteasome system (UPS), controls many cellular events by degrading short-lived regulatory proteins marked with polyubiquitin chains. The 20S proteolytic core protease (CP), the catalytic core of the 26S proteasome, is a central enzyme in the UPS. Its biogenesis proceeds in a multistep and orderly fashion assisted by a series of proteasome assembly chaperones. In this study, we identified a novel maize (Zea mays) kernel mutant named defective kernel40 (dek40), which produces small, collapsed kernels and exhibits delayed embryo and endosperm development. Dek40 was identified by map-based cloning and confirmed by transgenic functional complementation. Dek40 encodes a putative cytosol-localized proteasome biogenesis-associated chaperone4 (PBAC4) protein. DEK40 participates in the biogenesis of the 20S CP by interacting with PBAC3. Loss-of-function of DEK40 substantially affected 20S CP biogenesis, resulting in decreased activity of the 26S proteasome. Ubiquitylome analysis indicated that DEK40 influences the degradation of ubiquitinated proteins and plays an essential role in the maintenance of cellular protein homoeostasis. These results demonstrate that Dek40 encodes a PBAC4 chaperone that affects 20S CP biogenesis and is required for 26S proteasome function and seed development in maize.

Comprehensive proteomic analysis of developing protein bodies in maize (Zea mays) endosperm provides novel insights into its biogenesis.

Prolamins, the major cereal seed storage proteins, are sequestered and accumulated in the lumen of the endoplasmic reticulum (ER), and are directly assembled into protein bodies (PBs). The content and composition of prolamins are the key determinants for protein quality and texture-related traits of the grain. Concomitantly, the PB-inducing fusion system provides an efficient target to produce therapeutic and industrial products in plants. However, the proteome of the native PB and the detailed mechanisms underlying its formation still need to be determined. We developed a method to isolate highly purified and intact PBs from developing maize endosperm and conducted proteomic analysis of intact PBs of zein, a class of prolamine protein found in maize. We thus identified 1756 proteins, which fall into five major categories: metabolic pathways, response to stimulus, transport, development, and growth, as well as regulation. By comparing the proteomes of crude and enriched extractions of PBs, we found substantial evidence for the following conclusions: (i) ribosomes, ER membranes, and the cytoskeleton are tightly associated with zein PBs, which form the peripheral border; (ii) zein RNAs are probably transported and localized to the PB-ER subdomain; and (iii) ER chaperones are essential for zein folding, quality control, and assembly into PBs. We futher confirmed that OPAQUE1 (O1) cannot directly interact with FLOURY1 (FL1) in yeast, suggesting that the interaction between myosins XI and DUF593-containing proteins is isoform-specific. This study provides a proteomic roadmap for dissecting zein PB biogenesis and reveals an unexpected diversity and complexity of proteins in PBs.