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Ultrafine‐grained microstructure and face center cubic (FCC) phase are produced in the pure titanium foils through asymmetrical rolling (ASR) to explore the mechanical properties of pure titanium foils with different thicknesses. Herein, the grain refinement process and phase transformation behavior are systematically investigated. The grain refinement process can be described as: 1) coarse equiaxed grains are elongated along RD due to the compressive strain and shear strain caused by the ASR process. 2) elongated grains are split into thin laths and subgrains by dislocation walls under greater strain. 3) thin laths and subgrains are further refined and ultrafine‐grained microstructures are obtained. In addition, hexagonal close‐packed (HCP)‐FCC phase transformation is also discovered during the ASR process. The orientation relationship between the HCP and FCC phases is determined as [0001]HCP//[001]FCC, (101_0)HCP//(2_20)FCC and the phase transformation is caused by Shockley partial dislocation with Burgers vector 1/6[110]2_ gliding on each (101_0) plane. Uniaxial tensile tests on heat‐treated pure titanium foils of different thicknesses show a size effect on tensile properties. As the thickness decreases, tensile strength and elongation are reduced, with fewer/single‐layer equiaxed grains at the section of the specimen. [ABSTRACT FROM AUTHOR]

Carbonization is an effective way to achieve the comprehensive utilization of coal. However, the in situ variation of graphite‐like microcrystals, the basic structure of coal macromolecules, with heating and cooling during carbonization has not been fully characterized so far. Anthracite is a type of humic coal with the highest degree of coalification, and its structure change can be monitored well by X‐ray scattering or diffraction techniques. In this contribution, an in situ synchrotron radiation wide‐angle X‐ray scattering (WAXS) study on high‐temperature (1200°C) carbonization of a high‐quality anthracite mined in Jincheng, China, is presented. The results show that, during the continuous process of heating and cooling, the size and height of the aromatic lamellae first decrease and then increase with minima at 900 and 1000°C, respectively, while the interlayer spacing first increases and then decreases with a maximum at 1000°C. The roadmap of graphite‐like microcrystalline structure change during the whole continuous process of heating and cooling is revealed and described. [ABSTRACT FROM AUTHOR]

Objectives: To evaluate the feasibility of a new simple ultrasound‐guided transforaminal injection in patients with cervical radiculopathy. Methods: Ultrasound scans of the neck in a plastic model and in 5 unaffected participants were first performed to identify the intervertebral foramen. Then ultrasound‐guided transforaminal injections were performed in 20 patients with radiculopathy in the lower cervical spine, and computed tomography was used to verify the accuracy. Complications, the visual analog score, and the neck disability index were assessed at 1 and 3 months after the injection. Results: Computed tomography confirmed that the needle tip was correctly placed in the intervertebral foramen in 88.5% (23 of 26) of injections. No immediate or short‐term complications were observed in all patients. The visual analog score and neck disability index at 1 and 3 months were significantly lower than those before the injection (both P <.0001). Conclusions: Ultrasound may be a feasible and accurate method to guide cervical transforaminal injection. [ABSTRACT FROM AUTHOR]

Objectives: Super‐resolution ultrasound (SRUS) has become a tool for in vivo microvascular imaging. Most of the SRUS methods are based on microbubble localization: namely, ultrasound localization microscopy (ULM). The aim of this study was to develop a nonlocalization SRUS method and verify its feasibility in microvascular imaging. Methods: We introduce a new super‐resolution strategy based on the postprocessing of contrast‐enhanced ultrasound. The proposed method, which is termed ultrasound diffraction attenuation microscopy (UDAM), uses super‐resolution radial fluctuations instead of microbubble localization to overcome acoustic diffraction limits. Biceps of Japanese long‐ear white rabbits were adopted to validate its feasibility on muscle vascular imaging, using a clinical accessible ultrasound system at a frame rate of 30 Hz under a single bolus injection of SonoVue (Bracco SpA, Milan, Italy). The super‐resolution image was compared with the maximum‐intensity projection and ULM. Results: The animal study illustrates that the proposed UDAM can obtain super‐resolution microvascular images of rabbits' muscles under a single bolus injection of SonoVue with a 150‐second contrast‐enhanced ultrasound video. Both ULM and UDAM can achieve a very similar vascular structure with the maximum‐intensity projection but much higher spatial resolution. The measurement of 1‐dimensional signals shows that UDAM can distinguish the subwavelength structures and substantial reduce the full width at half‐maximum of microvessels. Conclusions: We conclude UDAM provides a noninvasive tool for in vivo super‐resolution microvascular imaging. [ABSTRACT FROM AUTHOR]

Spreading depolarization (SD) occurs frequently in the injured brain, and its neurochemical effects are detrimental to brain function. We report the first observation that the release of ascorbate, an important neurochemical in the brain, is closely accompanied with SD. Ascorbate was monitored with carbon nanotube (CNT)‐sheathed carbon fiber microelectrodes (CFEs). This system features high selectivity and temporal/spatial resolution. With our sensor, we observed a significant increase in the concentration of ascorbate in response to SD induction. Mechanistic studies show a contrasting behavior; with a SD specific inhibitor, release was completely suppressed, whereas with inhibition of commonly employed glutamate transporters, ascorbate release was increased, demonstrating a powerful means of discriminating ascorbate release between disputed pathways. Most importantly, we observed the propagative nature of ascorbate release following SD. [ABSTRACT FROM AUTHOR]

Naoxintong ( NXT) is a Chinese Materia Medica standardized product extracted from 16 various kinds of Chinese traditional herbal medicines including Salvia miltiorrhiza, Angelica sinensis, Astragali Radix. Naoxintong is clinically effective in treating ischaemia heart disease. Nucleotide-binding oligomerization domain-Like Receptor with a Pyrin domain 3 ( NLRP3) inflammasome has been critically involved in myocardial ischaemia/reperfusion (I/R) injury. Here, we have been suggested that NXT might attenuate myocardial I/R injury via suppression of NLRP3 inflammasome activation. Male C57 BL6 mice were subjected to myocardial I/R injury via 45 min. coronary ligation and release for the indicated times. Naoxintong (0.7 g/kg/day) and PBS were orally administrated for 2 weeks before surgery. Cardiac function assessed by echocardiography was significantly improved in the NXT group compared to PBS group at day 2 after myocardial I/R. NLRP3 inflammasome activation is crucially involved in the initial inflammatory response after myocardial I/R injury, leading to cleaved caspase-1, mature interleukin ( IL)-1β production, accompanying by macrophage and neutrophil infiltration. The cardioprotective effect of NXT was associated with a diminished NLRP3 inflammasome activation, decreased pro-inflammatory macrophage (M1 macrophages) and neutrophil infiltration after myocardial I/R injury. In addition, serum levels of IL-1β, indicators of NLRP3 inflammasome activation, were also significantly suppressed in the NXT treated group after I/R injury. Naoxintong exerts cardioprotive effects at least partly by suppression of NLRP3 inflammasome activation in this I/R injury model. [ABSTRACT FROM AUTHOR]

Electrochemistry is one of the most advanced techniques for monitoring neurochemical activities in the living brain because electrochemical approaches bear the advantageous features of high spatial and temporal resolutions, which facilitate its tremendous potential in investigating the highly spatially heterogeneous brain system and the fast dynamics of neurochemical activities. On the other hand, since brain is the most complicated organ in the sense of its numerous kinds of neurochemical species, high selectivity is always required for any analytical methods that approach the brain. In this review, we will discuss various electrochemical methodologies to achieve selective detection of neurochemicals in mammalian brain and the strategies developed mainly by our group towards selective monitoring of both electrochemically active and inactive neurochemicals. At the end, we will discuss possible solutions towards brain mapping of neurochemical species and combination of neurochemical detection strategy with electrophysiology as the direction of future development of electroanalysis in living brain. [ABSTRACT FROM AUTHOR]

ABSTRACT The subsynovial connective tissue (SSCT) is a viscoelastic structure connecting the median nerve (MN) and the flexor tendons in the carpal tunnel. Increased strain rates increases stiffness in viscoelastic tissues, and thereby its capacity to transfer shear load. Therefore, tendon excursion velocity may impact the MN displacement. In carpal tunnel syndrome (CTS) the SSCT is fibrotic and may be ruptured, and this may affect MN motion. In this study, ultrasonography was performed on 14 wrists of healthy controls and 25 wrists of CTS patients during controlled finger motions performed at three different velocities. Longitudinal MN and tendon excursion were assessed using a custom speckle tracking algorithm and compared across the three different velocities. CTS patients exhibited significantly less MN motion than controls ( p ≤ 0.002). While in general, MN displacement increased with increasing tendon excursion velocity ( p ≤ 0.031). These findings are consistent with current knowledge of SSCT mechanics in CTS, in which in some patients the fibrotic SSCT appears to have ruptured from the tendon surface. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:483-487, 2015. [ABSTRACT FROM AUTHOR]

α6β2* nicotinic acetylcholine receptors (nAChRs)s in the ventral tegmental area to nucleus accumbens (NAc) pathway are implicated in the response to nicotine, and recent work suggests these receptors play a role in the rewarding action of ethanol. Here, we studied mice expressing gain-of-function α6β2* nAChRs (α6L9′S mice) that are hypersensitive to nicotine and endogenous acetylcholine. Evoked extracellular dopamine (DA) levels were enhanced in α6L9′S NAc slices compared to control, non-transgenic (non-Tg) slices. Extracellular DA levels in both non-Tg and α6L9′S slices were further enhanced in the presence of GBR12909, suggesting intact DA transporter function in both mouse strains. Ongoing α6β2* nAChR activation by acetylcholine plays a role in enhancing DA levels, as α-conotoxin MII completely abolished evoked DA release in α6L9′S slices and decreased spontaneous DA release from striatal synaptosomes. In HPLC experiments, α6L9′S NAc tissue contained significantly more DA, 3,4-dihydroxyphenylacetic acid, and homovanillic acid compared to non-Tg NAc tissue. Serotonin (5-HT), 5-hydroxyindoleacetic acid, and norepinephrine (NE) were unchanged in α6L9′S compared to non-Tg tissue. Western blot analysis revealed increased tyrosine hydroxylase expression in α6L9′S NAc. Overall, these results show that enhanced α6β2* nAChR activity in NAc can stimulate DA production and lead to increased extracellular DA levels. [ABSTRACT FROM AUTHOR]

ABSTRACT 1,6-Hexanediol diacrylate (HDDA), pentaerythrithyl tetramethacrylate (PETMA), and triallyl-isocyanurate (TAIC) were used as representative monomers to modify polypropylene (PP) in the presence of dicumyl peroxide (DCP) in a mixer. Fourier transformed infrared spectroscopy (FTIR) results confirmed that all the three polyfunctional monomers have been grafted on PP backbone. The shape of torque curves suggested the occurrence of grafting and/or crosslinking structure. The rheological behaviors of HDDA modified PP showed the highest G′ and lowest tan δ at low frequency, shear-thinning shifted to lower frequency in η*-ω plot, as well as more deviation from semicircle characteristic of linear PP at high viscosity in Cole-Cole plot. And, the improvement of the mechanical properties followed the order as below: TAIC < PETMA < HDDA. Meanwhile, the foamability of the modified PP samples was also investigated. The cellular structure and morphology of the obtained foams were observed by scanning electron microscopy (SEM), and the results indicated that the foamability of the three modified PPs followed the same order, demonstrating HDDA modified PP foam possessed the highest cell density and expansion ratio, and the most well-defined closed cell structure and uniformly cellular morphology. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 1675-1681, 2013 [ABSTRACT FROM AUTHOR]

In this work, zinc N, N-dimethyldithiocarbamate (ZDMC) was used to mediate the melt modification of polypropylene (PP) with 1,6-hexanediol diacrylate (HDDA) in an internal mixer in the presence of dicumyl peroxide (DCP). Fourier transformed infrared spectroscopy analysis revealed that HDDA was directly grafted onto PP backbone. The dependence of torque on processing time indicated that the presence of ZDMC restrained the degradation of PP, and the end-torque value increased with the addition of ZDMC. Dynamic rheological measurement indicated that the modified PP possessed higher G′ and lower tan δ at low frequency, displaying an increase in η* and disappearance of Newtonian plateau in η*-ω plot, as well as larger radius of semicircle in Cole-Cole plot. All the rheological characterizations, together with the decreased gel content with the increase of ZDMC, confirmed the formation of long-chain branching. Subsequently, the foamability of the modified samples was investigated by one-step compression-molding process. The cellular structure and morphology of the obtained foams were observed by scanning electron microscopy, and the results showed that the addition of ZDMC decreased the cell size, increased the cell density, and brought about well-defined closed cell structure. POLYM. ENG. SCI., 2013. © 2012 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

Purpose. To analyze retrospectively the sonographic characteristics of the peripheral nerve injuries (PNIs) resulted from Wunchuan earthquake. Methods. The sonographic images of 38 patients with surgically proved PNIs were reviewed and compared with the surgical findings. Results. A total of 78 nerves in 38 patients were found injured in surgery, which included 16 median nerves in the forearm (20.5%), 6 ulnar nerves in the forearm or arm (7.7%), 8 radial nerves in upper limb (10.0%), 8 sciatic nerves (10.3%) in gluteal region, 17 tibial nerves in the leg (21.8%), and 23 peroneal nerves (29.5%). The most common injured nerve in the lower extremity was the peroneal nerve (29.5%) and in upper extremity was the median nerve (20.5%). Sonography correctly diagnosed 72 earthquake-related nerve injuries (92.3%), which included 5 complete disruption (6.4%), 4 partial disruption (5.1%), 63 nerve entrapment (88.5%, included 1 entrapment by bone calus, 38 entrapments by the scar tissue, 13 entrapments by the thickened muscle or tendinous arch, and 11 entrapment in the narrowed osteofibrous tunnels). Conclusions. Nerve entrapment injury was the common sonographic finding in earthquake-related PNI. © 2011 Wiley Periodicals, Inc. J Clin Ultrasound, 2011; [ABSTRACT FROM AUTHOR]

Purpose: To investigate the value of sonography in the diagnosis of fibromatosis. Method: We retrospectively reviewed the sonographic findings, pathologic results, and other medical records of 42 patients with pathologically proven fibromatosis. The tumor's size and location were recorded. Echogenicity, margins, vascularity, and relationship with the adjacent tissue were analyzed. Results: A total of 42 patients with 44 lesions were included in the study. In 21 patients, the tumor was a primary tumor. In 7 of these patients, a preoperative diagnosis of fibromatosis was obtained via sonographically guided biopsy or surgical biopsy. In another 21 patients, the tumor was a recurrence (including 1 case of malignant transformation). Well-defined and regular margins were demonstrated in 26 lesions (59%), whereas poorly defined and irregular borders were seen in the other 18 lesions. On Doppler imaging, vascularity was absent in 66% (29/44) lesions, moderate in 23% (10/44), and marked in 11% (5/44). Infiltration into the adjacent skeletal muscles, cortical bone, or encasement vessels, nerves, or tendons was found in 21 (48%) lesions. Conclusion: In patients with fibromatosis, sonography demonstrates a nonspecific hypoechoic solid mass and can guide the percutaneous needle biopsy. [ABSTRACT FROM AUTHOR]

Review: 118 refs. [ABSTRACT FROM AUTHOR]

Pancreatic ductal adenocarcinoma (PDAC) is a devastating disease with an overall 5-year survival rate of <12% due to the lack of effective treatments. Novel treatment strategies are urgently needed. Here, PKMYT1 is identified through genome-wide CRISPR screens as a non-mutant, genetic vulnerability of PDAC. Higher PKMYT1 expression levels indicate poor prognosis in PDAC patients. PKMYT1 ablation inhibits tumor growth and proliferation in vitro and in vivo by regulating cell cycle progression and inducing apoptosis. Moreover, pharmacological inhibition of PKMYT1 shows efficacy in multiple PDAC cell models and effectively induces tumor regression without overt toxicity in PDAC cell line-derived xenograft and in more clinically relevant patient-derived xenograft models. Mechanistically, in addition to its canonical function of phosphorylating CDK1, PKMYT1 functions as an oncogene to promote PDAC tumorigenesis by regulating PLK1 expression and phosphorylation. Finally, TP53 function and PRKDC activation are shown to modulate the sensitivity to PKMYT1 inhibition. These results define PKMYT1 dependency in PDAC and identify potential therapeutic strategies for clinical translation., (© 2024. The Author(s).)