Identification and characterization of enzymes responsible for methylglyoxal overproduction in the metabolic syndrome

Methylglyoxal (MG) is a highly reactive metabolite produced in the cells. Insulin-insensitive vascular cells are the major sites for endogenous MG formation. Elevated levels of MG in vascular tissues were reported in metabolic syndrome with hyperglycemia (such as type 2 diabetes) or without hyperglycemia (such as hypertension), but the underlying mechanism is largely unknown. We observed that in cultured vascular smooth muscle cells (VSMCs), fructose (25 mM) treatment up-regulated gene expression of aldolase B and enhanced MG formation. Glucose (25 mM) treatment of VSMCs activated the polyol pathway and increased fructose formation, leading to aldolase B up-regulation and MG overproduction. In our tested rat models with obesity, hypertension or diabetes, serum and aortic MG and fructose levels were increased, and the expression of aldolase B in the aorta was up-regulated. Our study indicates that aldolase B up-regulation by elevated fructose is a common mechanism for vascular MG overproduction in the metabolic syndrome. Increased MG accumulation is considered an important molecular mechanism for endothelial cell damage in diabetes. Whether knockdown of aldolase B prevents high glucose-induced MG overproduction and cellular dysfunction was investigated in the cultured endothelial cells. High glucose (25 mM) incubation increased aldolase B mRNA expression and MG formation in endothelial EA. hy926 cells. We found that siRNA knockdown of aldolase B prevented high glucose-elevated MG levels and the activation of multiple metabolic and signaling pathways (i.e. increase in advanced glycation endproducts accumulation, oxidative stress, O-linked N-acetyl glucosamine modification of proteins, membrane protein kinase C activity and nuclear translocation of nuclear factor κB). Our study further suggests that aldolase B is likely a key target for prevention of MG overproduction and related cellular dysfunction not only in VSMCs but also in vascular endothelial cells in diabetes and its vascular complications. Recently, MG formation in insulin-sensitive cells has received much attention since high levels of MG have been found to disturb insulin signaling in 3T3-L1 adipocytes and skeletal muscle L6 cells. We, therefore, investigated the mechanisms for MG formation in insulin-sensitive 3T3-L1 adipocytes under physiological and pathological conditions. We found that insulin (100 nM), glucose (25 mM), or their combination has no effect on cellular levels of sorbitol and fructose, in comparison with the control group (5 mM glucose alone). Insulin, glucose (25 mM), or their combination decreased aldolase B mRNA to a similar level. Glucose (25 mM) had no effect on aldolase A gene expression, but insulin (100 nM) markedly increased aldolase A mRNA and protein levels in the absence or presence of 25 mM glucose. Application of insulin (100 nM) increased the levels of basal or glucose (25 mM)-induced MG and glucose 6-phosphate. Knockdown of aldolase A prevented the increased MG levels induced by insulin (100 nM), glucose (25 mM), or their combination. Our data suggest that aldolase A and glycolysis are responsible for the basal and excess MG generation in insulin-sensitive adipose cells, especially under the stimulus of insulin. In summary, all experiments taken together, show for the first time, that aldolase B is responsible for vascular MG overproduction and aldolase A is responsible for adipose MG overproduction in metabolic syndrome. Increased MG levels in these cells may contribute to endothelial dysfunction, pathogenesis of hypertension and hypertriglyceridemia that characterize the metabolic syndrome

Experimental Study on the Measurement of Water Bottom Vibration Induced by Underwater Drilling Blasting

Due to the lack of proper instrumentations and the difficulties in underwater measurements, the studies about water bottom vibration induced by underwater drilling blasting are seldom reported. In order to investigate the propagation and attenuation laws of blasting induced water bottom vibration, a water bottom vibration monitor was developed with consideration of the difficulties in underwater measurements. By means of this equipment, the actual water bottom vibration induced by underwater drilling blasting was measured in a field experiment. It shows that the water bottom vibration monitor could collect vibration signals quite effectively in underwater environments. The followed signal analysis shows that the characteristics of water bottom vibration and land ground vibration induced by the same underwater drilling blasting are quite different due to the different geological environments. The amplitude and frequency band of water bottom vibration both exceed those of land ground vibration. Water bottom vibration is mainly in low-frequency band that induced by blasting impact directly acts on rock. Besides the low-frequency component, land vibration contains another higher frequency band component that induced by followed water hammer wave acts on bank slope

Experimental study on ground vibration of blasting the boulder with tandem shaped charging warhead

Hazardous effects of blasting the boulder with the new breaking-blasting equipment-tandem shaped charging warhead are mainly air shock wave, seismic wave and blast slung shot. Blast-induced ground vibration is one of the inevitable effects and may cause substantial damage to nearby structures. Started from the formation process and mechanism of ground vibration to study the seismic wave, the research attained curve of vibration velocity of monitoring points by TC-4850 and carried out differential and fast Fourier transform analysis of the curve. And the results concluded that blasting vibration with tandem shaped charging warhead mainly comes from prime charge; the attenuation law can be predicted by Sadev’s Formula. Explosion vibration frequency range is 20-150 Hz, while with the increase of distance from the blasting center, blasting vibration intensity attenuates rapidly, vibration duration increases and vibration frequency gradually reduces. Compared with general rock blasting, its attenuation rate of blasting vibration is faster with higher frequency and smaller impact on buildings, but the harm effects should not be ignored for the special application environment

Neural oscillations during acupuncture imagery partially parallel that of real needling

IntroductionTasks involving mental practice, relying on the cognitive rehearsal of physical motors or other activities, have been reported to have similar patterns of brain activity to overt execution. In this study, we introduced a novel imagination task called, acupuncture imagery and aimed to investigate the neural oscillations during acupuncture imagery.MethodsHealthy volunteers were guided to watch a video of real needling in the left and right KI3 (Taixi point). The subjects were then asked to perform tasks to keep their thoughts in three 1-min states alternately: resting state, needling imagery left KI3, and needling imagery right KI3. Another group experienced real needling in the right KI3. A 31-channel-electroencephalography was synchronously recorded for each subject. Microstate analyses were performed to depict the brain dynamics during these tasks.ResultsCompared to the resting state, both acupuncture needling imagination and real needling in KI3 could introduce significant changes in neural dynamic oscillations. Moreover, the parameters involving microstate A of needling imagery in the right KI3 showed similar changes as real needling in the right KI3.DiscussionThese results confirm that needling imagination and real needling have similar brain activation patterns. Needling imagery may change brain network activity and play a role in neural regulation. Further studies are needed to explore the effects of acupuncture imagery and the potential application of acupuncture imagery in disease recovery

Increased Renal Methylglyoxal Formation with Down-Regulation of PGC-1α-FBPase Pathway in Cystathionine γ-Lyase Knockout Mice

We have previously reported that hydrogen sulfide (H2S), a gasotransmitter and vasodilator has cytoprotective properties against methylglyoxal (MG), a reactive glucose metabolite associated with diabetes and hypertension. Recently, H2S was shown to up-regulate peroxisome proliferator-activated receptor-γ coactivator (PGC)-1α, a key gluconeogenic regulator that enhances the gene expression of the rate-limiting gluconeogenic enzyme, fructose-1,6-bisphosphatase (FBPase). Thus, we sought to determine whether MG levels and gluconeogenic enzymes are altered in kidneys of 6–22 week-old cystathionine γ-lyase knockout (CSE-/-; H2S-producing enzyme) male mice. MG levels were determined by HPLC. Plasma glucose levels were measured by an assay kit. Q-PCR was used to measure mRNA levels of PGC-1α and FBPase-1 and -2. Coupled-enzymatic assays were used to determine FBPase activity, or triosephosphate levels. Experimental controls were either age-matched wild type mice or untreated rat A-10 cells. Interestingly, we observed a significant decrease in plasma glucose levels along with a significant increase in plasma MG levels in all three age groups (6–8, 14–16, and 20–22 week-old) of the CSE-/- mice. Indeed, renal MG and triosephosphates were increased, whereas renal FBPase activity, along with its mRNA levels, were decreased in the CSE-/- mice. The decreased FBPase activity was accompanied by lower levels of its product, fructose-6-phosphate, and higher levels of its substrate, fructose-1,6-bisphosphate in renal extracts from the CSE-/- mice. In agreement, PGC-1α mRNA levels were also significantly down-regulated in 6-22 week-old CSE-/- mice. Furthermore, FBPase-1 and -2 mRNA levels were reduced in aorta tissues from CSE-/- mice. Administration of NaHS, a H2S donor, increased the gene expression of PGC-1α and FBPase-1 and -2 in cultured rat A-10 cells. In conclusion, overproduction of MG in CSE-/- mice is due to a H2S-mediated down-regulation of the PGC-1α-FBPase pathway, further suggesting the important role of H2S in the regulation of glucose metabolism and MG generation

AI is a viable alternative to high throughput screening: a 318-target study

: High throughput screening (HTS) is routinely used to identify bioactive small molecules. This requires physical compounds, which limits coverage of accessible chemical space. Computational approaches combined with vast on-demand chemical libraries can access far greater chemical space, provided that the predictive accuracy is sufficient to identify useful molecules. Through the largest and most diverse virtual HTS campaign reported to date, comprising 318 individual projects, we demonstrate that our AtomNet® convolutional neural network successfully finds novel hits across every major therapeutic area and protein class. We address historical limitations of computational screening by demonstrating success for target proteins without known binders, high-quality X-ray crystal structures, or manual cherry-picking of compounds. We show that the molecules selected by the AtomNet® model are novel drug-like scaffolds rather than minor modifications to known bioactive compounds. Our empirical results suggest that computational methods can substantially replace HTS as the first step of small-molecule drug discovery

Control of salt structures on hydrocarbons in the passive continental margin of West Africa

Salt basins along the passive continental margin of West Africa are becoming one of the most attractive areas for hydrocarbon exploration. The oil and gas discovered recently are related to salt structures. The salt structures are widespread in Anglo-Cameroon, the thickness of salt is up to 1 500 m and the average width is 300 km. These basins can be divided into two parts in horizontal direction: extensional zone and compressional zone, which extend 100–150 km and 100–200 km respectively. The extensional zone includes sealed titled zone, growth fault zone and diapir zone, and is characterized by tilted block, rollover structure and turtle structure anticline. The compressional zone is characterized by salt sheet, salt tongue, thrust fault and small folds. Oil and gas are distributed in both zones, oil and gas reserves in the extensional zone are a little larger than reserves in the compressional zone. Several types of salt related traps can be recognized, such as salt anticline, salt diapir and fault related trap, unconformity and structural-lithologic traps. Salt anticlines are the most potential exploration targets. Key words: West Africa, passive continental margin, salt structure, extensional zone, compressional zon

TrnH-psbA sequence analyses of asparagus cochinchinensis from different geographical origin in China

This template explains and demonstrates how to prepare your camera-ready paper for The trnH-psbA sequences of 13 Asparagus cochinchinensis populations from 6 provinces of China were studied. The results showed that length of trnH-psbA change and the mutation of GC content were small. The length of trnH-psbA sequences were from 619 bp to 632 bp, and the GC content was about 36%. The total variation rates of 13 populations were from 2.21% to 3.47%, when the missing sites were considered as variation sites. A. cochinchinensis from different sources had 10 information sites in trnH-psbA sequence, accounting for 1.58% of the total sequence. The information sites were located in the sites 8, 9, 120, 457, 458, 486, 487, 491, 492, and 593, respectively. Clustering analysis showed that the Qianxi and Hengshan populations clustered together; Dushan, Yuqing, and Guangzhou populations were grouped; Nanning and Xinning populations formed another cluster. trnH-psbA sequences could identify different A. cochinchinensis populations. Clustering of different A. cochinchinensis populations related primarily to latitude and had little relationship with longitude

TrnH-psbA sequence analyses of asparagus cochinchinensis from different geographical origin in China

This template explains and demonstrates how to prepare your camera-ready paper for The trnH-psbA sequences of 13 Asparagus cochinchinensis populations from 6 provinces of China were studied. The results showed that length of trnH-psbA change and the mutation of GC content were small. The length of trnH-psbA sequences were from 619 bp to 632 bp, and the GC content was about 36%. The total variation rates of 13 populations were from 2.21% to 3.47%, when the missing sites were considered as variation sites. A. cochinchinensis from different sources had 10 information sites in trnH-psbA sequence, accounting for 1.58% of the total sequence. The information sites were located in the sites 8, 9, 120, 457, 458, 486, 487, 491, 492, and 593, respectively. Clustering analysis showed that the Qianxi and Hengshan populations clustered together; Dushan, Yuqing, and Guangzhou populations were grouped; Nanning and Xinning populations formed another cluster. trnH-psbA sequences could identify different A. cochinchinensis populations. Clustering of different A. cochinchinensis populations related primarily to latitude and had little relationship with longitude