To date, imaging of malignant glioma remains challenging. In positron emission tomography-related diagnostic imaging, differential tumor uptake of 3'-deoxy-3'-(18)F fluorothymidine ((18)FFLT) has ...been shown to reflect the levels of cell proliferation and DNA synthesis. However, additional biomarkers for tumors are urgently required. Aberrant levels of glutathione transferase (GST) activity have been hypothesized to constitute such a novel diagnostic marker. Here, a C6 rat glioma tumor model was used to assess the ability of the positron emission tomography tracers, (18)FFLT and (18)F-fluorobutyl ethacrynic amide ((18)FFBuEA), to indicate reactive oxygen species-induced stress responses as well as detoxification-related processes in tumors. Using a GST activity assay, we were able to demonstrate that FBuEA is more readily catalyzed by GST-π than by GST-α. Furthermore, we showed that FBuEA-GS, a metabolite of FBuEA, elicits greater cytotoxicity in tumor cells than in normal fibroblast cells. Finally, in vitro and in vivo investigation of radiotracer distribution of (18)FFBuEA and (18)F FBuEA-GS revealed preferential accumulation in C6 glioma tumor cells over normal fibroblast cells for (18)FFBuEA-GS but not for (18)FFBuEA.
Summary
Background
The occurrence rate and severity of gastroesophageal reflux disease with erosive esophagitis (EE) in patients after converting nasogastric tube (NGT) feeding to percutaneous ...endoscopic gastrostomy (PEG) are not well‐known. The aim of this study was to determine the influence of PEG placement on the occurrence and severity of EE in patients with long‐term PEG feeding.
Methods
This retrospective study included patients with NGT feeding who were converted to PEG feeding and received pre‐ and post‐PEG endoscopy between January 2000 and June 2013. Factors predictive of the occurrence of EE after PEG were analyzed.
Results
One‐hundred and twenty patients with NGT feeding were converted to PEG, and 47 patients were included. Before PEG, 21 (44.7%) NGT‐feeding patients had EE. The mean follow‐up time was 45.7 months (range, 6–147 months). Erosive esophagitis occurred in nine (19.1%) patients after PEG. The occurrence rate (p < 0.01) and severity (p < 0.05) of EE significantly improved after PEG, compared to before PEG. Hill's classification of gastroesophageal valve was associated with the occurrence of EE after PEG (p < 0.01).
Conclusion
The occurrence and severity of esophagitis improved after converting the patient to PEG. Hill's grading of gastroesophageal valve provides useful information for predicting the occurrence of EE after PEG.
18FFlurobutyl ethacrynic amide (18FFBuEA) was prepared from the precursor tosylate N-Boc-N-4-(toluenesulfonyloxy)butylethacrynic amide with a radiochemical yield of 3%, a specific activity of ...48GBq/μmol and radiochemical purity of 98%. Chemical conjugation of 18FFBuEA with glutathione (GSH) via a self-coupling reaction and enzymatic conjugation under catalysis of glutathiontransferase alpha (GST-α) and π provided about 41% yields of radiochemical conjugated product 18FFBuEA–GSH, 85% and 5–16%, respectively. The catalytic selectivity of this tracer toward GST-alpha was addressed. Positron emission tomography (PET) imaging of 18FFBuEA in normal rats showed that a homogeneous pattern of radioactivity was distributed in the liver, suggesting a catalytic role of GST. By contrast, PET images of 18FFBuEA in rats with thioacetamide-induced cholangiocarcinoma displayed a heterogeneous pattern of radioactive accumulation with cold spots in tumor lesions. PET imaging with 18FFBuEA could be used for early diagnosis of hepatic tumor with a low GST activity as well as liver function.
Background Patients with cytomegalovirus (CMV) colitis have increasingly been recognized among critically ill patients, yet few specific clinical and endoscopic features are known. In this study, we ...investigated the common clinical and endoscopic features of CMV colitis in critically ill patients. Methods From January 1, 2000 to February 28, 2014, patients with a histopathological diagnosis of CMV colitis were retrospectively reviewed. We reviewed and analyzed the clinical presentation, primary diseases, serum CMV antibody, treatment, mortality, and endoscopic features of these patients. Results Eighteen patients were diagnosed as having CMV colitis and 15 CMV colitis patients were included in this study. The mean age was 65.7 years (range 42–92 years). Bloody diarrhea and persistent diarrhea were the most common initial presentations of CMV, and sepsis was the most common comorbidity found. CMV-IgM was positive in three (17%) patients, and CMV-IgG was positive in 14 (93.3%) patients. All patients received ganciclovir and 11 patients clinically improved. Four (26.6%) patients died and two patients had colon perforation. According to the severity of the diseases, endoscopic presentation of CMV colitis ranged from colonic mucosa edema, loss of vasculature, subepithelial hemorrhage, and circular or geographic ulcers to perforation. Ten (66.7%) patients had multiple ulcers and five (33.3%) patients had a single ulcer. Eleven (73.3%) patients had colitis involving distal to splenic flexure, and four (26.6%) patients had colitis involving the whole colon. Conclusion Critically ill patients who present with bloody stool or persistent diarrhea should be considered for the diagnosis of CMV colitis. The endoscopic presentation of CMV colitis is highly variable. We suggest that the endoscopic manifestation of CMV colitis can be divided into three stages: nonulcerative inflammatory stage, simple ulcerative stage, and complicated ulcerative stage.
Advanced AI edge chips require multibit input (IN), weight (W), and output (OUT) for CNN multiply-and-accumulate (MAC) operations to achieve an inference accuracy that is sufficient for practical ...applications. Computing-in-memory (CIM) is an attractive approach to improve the energy efficiency (EFMAC of MAC operations under a memory-wall constraint. Previous SRAM-CIM macros demonstrated a binary MAC 4, an in-array 8b W-merging with near-memory computing (NMC) using 6T SRAM cells (limited output precision) 5, a 7b1N-1 bW MAC using a 10T SRAM cell (large area) 3, an 4b1N-5bW MAC with a T8T SRAM cell 1, and 8b1N-1bW NMC with 8T SRAM (long MAC latency (TAC)) 2. However, previous works have not achieved high IN/W/OUT precision with fast TAC compact-area, high EFMAC, and robust readout against process variation, due to (1) small sensing margin in word-wise multiple-bit MAC operations, (2) a tradeoff between read accuracy vs. area overhead under process variation, (3) limited EFMAC due to decoupling of software and hardware development.
We present a 1.0Mb pipeline 6T SRAM in 40nm Low-Power CMOS technology. The design employs a variation-tolerant Step-Up Word-Line (SUWL) to improve the Read Static Noise Margin (RSNM) without ...compromising the Read performance and Write-ability. The Write-ability is further enhanced by an Adaptive Data-Aware Write-Assist (ADAWA) scheme. The 1.0Mb test chip operates from 1.5V to 0.7V, with operating frequency of 800MHz@1.2V and 25°C. The measured power consumption is 23.21mW (Active)/2.42mW (Leakage) at 1.2V, TT, 25°C; and 6.01mW (Active)/0.35mW (Leakage) at 0.7V, TT, 25°C.
We present an all-digital bit transistor characterization scheme for CMOS 6T SRAM array. The scheme employs an on-chip operational amplifier feedback loop to measure the individual threshold voltage ...(V TH ) of 6T SRAM bit cell transistors (holding PMOS, pull-down NMOS, and access NMOS) in SRAM cell array environment. The measured voltage is converted to frequency with dual VCO and counter based digital read-out to facilitate data extraction, processing, and statistical analysis. A 512Kb test chip is implemented in 55nm 1P10M Standard Performance (SP) CMOS technology. Monte Carlo simulations indicate that the accuracy of the V TH measurement scheme is about 2-7mV at TT corner across temperature range from 85°C to -45°C, and post-layout simulations show the resolution of the digital read-out scheme is <;60; 0.2mV per bit. Measured V TH distributions agree well with Monte Carlo simulation results.
This work proposes a novel Dual-Port (DP) 8T SRAM operation scheme. The scheme improves the Read stability and Write-ability, and allows asynchronous operation with arbitrary clock timing skew ...between two ports. It facilitates high performance, low-power and low V MIN with minimum device and area overhead. Post-simulation results show almost no timing penalty for simultaneous same-row access and the performance is almost the same as that for one port operation.
A dichlorinated alkaloid with a novel skeleton, chingazumianine (1), was isolated from the herb Corydalis koidzumiana, and its structure elucidated by spectroscopic data and X‐ray crystallographic ...analysis. In citrate‐treated human platelet‐rich plasma (PRP), known compounds, i.e., protopine (2), (±)‐tetrahydropalmatine (3), and palmatine (4), isolated from this plant, showed significant inhibition of secondary aggregation induced by adrenaline in a concentration‐dependent manner, suggesting that the antiplatelet effects of these compounds is mainly due to an inhibitory effect on thromboxane formation.
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