Junqing Zhang

Novel path computation element-based traffic grooming strategy in internet protocol over wavelength division multiplexing networks

With the emergence of various broadband services, a lot of bandwidth fragments will be generated during the operation of services being mapped into optical channels, which will waste too many bandwidth resources and decrease the transmission performance of optical networks. Traffic grooming strategy in dynamic optical networks can optimise the utilisation of bandwidth resources and reduce the blocking probability. However, in the distributed control plane of automated switched optical networks, all the traffic grooming strategies are implemented in each control node, and resource collision will still occur because the same link resource may be used by two path computation requests or traffic engineering information flooded by open shortest path first-traffic engineering protocol may be not synchronous at each control node or signalling delay time is too long. To reduce the collision of resource, a unified control plane is designed based on path computation element (PCE) for Internet protocol over wavelength division multiplexing networks, and a novel PCE-based traffic grooming strategy is proposed in the framework of unified control plane. Based on this strategy, four PCE-based traffic grooming algorithms are proposed and compared with the distributed traffic grooming strategy without PCE on a simulation platform implemented using disperse event simulation tool OMNET++.

Noise-Aware Wavelength Assignment for Wavelength Switched Optical Networks

In transparent WSON (wavelength switched optical networks), signals are switched optically and propagate thousands of kilometers without electrical regeneration. Over such distances, physical impairments, such as crosstalk, ASE noise and so on, can accumulate along the path and lead to signal quality degradation. If the admission of a lightpath will either cause its BER to be too high, or sufficiently degrade the performance of the already established lightpaths, it must be blocked. Most of recent research only consider the first case, but ignore the second case, which will lead to service interruption. In this paper, a new noise-aware wavelength assignment scheme called NAWA has been proposed, which use IIES (Impairments impact Evaluation Scheme) to solve both problems mentioned above in a distributed way. Simulations have been conducted and numerical results show that: Compared with normal impairment-aware solutions, NAWA can eliminate the occurrence of service interruption, and achieve better performance in total blocking.

Obesity Has an Interactive Effect with Genetic Variation in the Activating Transcription Factor 6 Gene on the Risk of Pre-Diabetes in Individuals of Chinese Han Descent

Endoplasmic reticulum (ER) stress is one of the contributing factors to the development of β-cell failure in type 2 diabetes. ER stress response through ATF6 has been shown to play an important role in insulin resistance and pancreatic β-cell function. We investigated whether genetic polymorphisms in ATF6 were associated with the risk of pre-diabetes in a Chinese Han population, and whether they had a synergistic effect with obesity. Our samples included 828 individuals who were diagnosed as pre-diabetic, and 620 controls. The minor allele A at rs2340721 was associated with increased risk for pre-diabetes(p = 0.013), and this association was still significant after adjusting for gender, age, body mass index (BMI), and waist-hip ratio(p′ = 0.011). BMI, treated as a continuous variable, and rs2340721 had an interactive effect on pre-diabetic risk(p for interaction = 0.003, β = 0.106). Carriers of GG at rs7522210 were also at a higher risk compared to non-carriers (OR = 1.390, 95%CI:1.206–1.818, p = 0.013, adjusted OR′ = 1.516, 95%CI:1.101–2.006, p′ = 0.006). GG homozygotes had increased fasting blood glucose (FBG) levels(GG vs CX: 5.6±0.52 vs 5.5±0.57 mmol/L, p = 0.016), lower insulin levels (0,30,120 minutes after glucose load) (p<0.05), and reduced areas under the insulin curve than non-carriers(GG vs CX:67.3(44.2–102.3) vs 73.1(49.4–111.4), p = 0.014). rs10918270 was associated with FBG, and rs4657103 with 2 hour glucose levels after a 75 g glucose load. We also identified a haplotype of TTAG composed of rs4657103, rs2134697, rs2340721, and rs12079579, which was associated with pre-diabetes. The genetic variation in ATF6 is associated with pre-diabetes and has interactive effects with BMI on pre-diabetes in the Chinese Han population.

ARMC5 mutations in familial and sporadic primary bilateral macronodular adrenal hyperplasia

To investigate Armadillo repeat-containing 5 (ARMC5) mutations in Chinese patients with familial and sporadic primary bilateral macronodular adrenal hyperplasia (PBMAH), we performed clinical data collection and ARMC5 sequencing for three PBMAH families and 23 sporadic PBMAH patients. ARMC5 pathogenic germline mutations were identified in all 3 PBMAH families. Secondary ARMC5 somatic mutations were found in two adrenal nodules from two PBMAH family members with ARMC5 germline mutations. PBMAH family members with ARMC5 pathogenic germline mutations displayed various clinical manifestations. ARMC5 pathogenic germline mutations were identified in 5 sporadic PBMAH patients among whom one patient displayed both hypercortisolism and primary aldosteronism. We detected a total of 10 ARMC5 pathogenic mutations, of which 8 had not been previously reported. Our results suggest that ARMC5 pathogenic germline mutations are common in familial and sporadic Chinese PBMAH patients, and demonstrate the importance of ARMC5 screening in PBMAH family members to detect patients with insidious PBMAH.

Glycine mitigates renal oxidative stress by suppressing Nox4 expression in rats with streptozotocin-induced diabetes

Glycine exerts renoprotective effects, but the mechanism remains unclear. Glycine is increasingly recognized as a factor that attenuates oxidative stress, a key mechanism underlying diabetic nephropathy. In this study, we investigated the effects of glycine on diabetic renal injury and oxidative stress by adding 1% glycine in the drinking water of rats with streptozotocin-induced diabetes for 20 weeks. Glycine levels decreased in the plasma and kidney homogenates of diabetic rats but were restored by oral glycine administration. In these diabetic rats, glycine attenuated renal damage, as evidenced by the decreased mesangial expansion, tubular interstitial fibrosis, and neutrophil gelatinase-associated lipocalin (NGAL) expression. Glycine also ameliorated the raise in urinary malondialdehyde (MDA) levels and partially restored renal glutathione levels in diabetic rats. Renal levels of the Nox4 mRNA and protein, a major source of renal oxidative stress, were suppressed by the treatment with glycine. Immunohistological analysis revealed that glycine had protective effects on the tubular area rather than the glomerular area. Our results strongly suggest that the protective effect of glycine on renal oxidative stress and structural damage may be linked to enhancement of GSH synthesis and suppression of renal Nox4 expression in diabetic rats.

Glycine Transporter-1 and glycine receptor mediate the antioxidant effect of glycine in diabetic rat islets and INS-1 cells

Abstract Oxidative stress is the main inducer of &bgr;‐cell damage, which underlies the pathogenesis of diabetes. Evidence suggests that glycine, a recognized antioxidant, may improve &bgr;‐cell function; however, its mechanism in protecting diabetic &bgr;‐cells against oxidative stress has not been directly investigated. Using a streptozotocin‐induced diabetic rat model and INS‐1 pancreatic &bgr;‐cells, we evaluated whether glycine can attenuate diabetic &bgr;‐cell damage induced by oxidative stress. In diabetic rats, glycine stimulated insulin secretion; enhanced plasma glutathione (GSH), catalase and superoxide dismutase levels; reduced plasma 8‐hydroxy‐2 deoxyguanosine and islet p22phox levels; and improved islet &bgr;‐cell mitochondrial degeneration and insulin granule degranulation. In INS‐1 cells, glycine reduced the intracellular reactive oxygen species (ROS) concentration and inhibited apoptosis induced by high glucose or H2O2. Glycine transporter‐1 inhibitor blocked the antioxidative effect of glycine by reducing the intracellular GSH content, and glycine receptor inhibitor reversed the glycine antioxidative effect by blocking p22phox. Collectively, our findings reveal a mechanism by which glycine protects diabetic &bgr;‐cells against damage caused by oxidative stress by increasing glycine transporter‐1‐mediated synthesis of GSH and by reducing glycine receptor‐mediated ROS production. Graphical abstract Figure. No Caption available. HighlightsEvidence suggests glycine may improve &bgr;‐cell function, but the mechanism is unclear.We used a streptozotocin‐induced diabetic rat model and INS‐1 pancreatic &bgr;‐cells.Glycines attenuation of &bgr;‐cell damage induced by oxidative stress was evaluated.Increased transporter‐1‐mediated GSH synthesis was a primary mechanism.Reduced receptor‐mediated ROS production also contributed.

Insoles Treated with Bacteria-Killing Nanotechnology Bio-Kil Reduce Bacterial Burden in Diabetic Patients and Healthy Controls

Our study investigated the effectiveness of bacteria-killing nanotechnology Bio-Kil socks on bacterial burden reduction in diabetic patients and healthy individuals. Four strains of S. aureus and four strains of E. coli were cultured and dropped on Bio-Kil socks and control socks for 0 h, 8 h, and 48 h of incubation. Diluted samples were inoculated and bacterial counts were recorded. Additionally, 31 patients with type 2 diabetes and 31 healthy controls were assigned to wear one Bio-Kil sock on one foot and a control sock on the other for four hours, and then they were told to exchange socks from one foot to the other for four hours. The socks were sampled and diluted and then inoculated to record bacterial counts. Bacterial counts were reduced in Bio-Kil socks compared with control socks in all S. aureus strains after 0 h, 8 h, and 48 h of incubation. In E. coli strains, bacterial counts declined in Bio-Kil socks comparing with control socks in most of the experiments with ESBL-negative E. coli and ATCC35218 at 0 h and 48 h of incubation. In all participants, the mean bacterial counts significantly decreased in Bio-Kil socks in comparison with control socks both at 0 h and at 40 h of incubation (p = 0.003 at 0 h and p = 0.006 at 40 h). Bio-Kil socks from diabetic patients showed significantly lessened bacterial count at 40 h of incubation (p = 0.003). In healthy individuals, Bio-Kil socks reflected a significantly smaller mean bacterial count than control socks (p = 0.016). Socks using Bio-Kil nanotechnology efficiently reduce bacterial counts in both diabetic patients and healthy individuals and might exert stronger efficacy in Gram-positive bacteria.

Genetic Variability of the Glucose-Dependent Insulinotropic Peptide Gene Is Involved in the Premature Coronary Artery Disease in a Chinese Population with Type 2 Diabetes

Background Glucose-dependent insulinotropic polypeptide (GIP) is closely related to diabetes and obesity, both of which are confirmed to increase the risk of coronary artery disease (CAD). Our study aimed to investigate whether the polymorphisms in GIP genes could affect the risk of cardiovascular disease in type 2 diabetic patients in the Chinese Han population. Methods We selected and genotyped two haplotype-tagging single nucleotide polymorphisms (tag-SNPs) (rs2291725 C>T, rs8078510 G>A) of GIP gene based on CHB data in HapMap Phase II database (r2 < 0.8). The case-control study of Chinese Han population involved 390 diabetic patients with CAD as positive group and 276 diabetic patients without CAD as control group. Allele and genotype frequencies were compared between the two groups. Results In dominant inheritance model, the carriers of T/T or T/C had a lower risk of CAD (OR = 0.635, 95% CI = 0.463–0.872, p = 0.005), even after adjustment other CAD risk factors (gender, age, BMI, smoking status, dyslipidemia, hypertension history, and diabetic duration) (OR′ = 0.769, 95% CI′ = 0.626–0.945, p′ = 0.013). The allele A at rs8078510 was associated with decreased risk of CAD (OR = 0.732, p = 0.039). p = 0.018 in subgroup analysis, individuals with higher BMI (≥24 kg/m2) had increased risk for CAD when carrying C/C at rs2291725 (OR′ = 1.291, 95% CI′ = 1.017–1.639, p′ = 0.036). In age < 55 men and age < 65 women, the carriers of allele C at rs2291725 had a higher risk of CAD than noncarriers (OR = 1.627, p = 0.015). Carriers of allele G in rs8078510 had higher susceptibility to CAD (OR = 2.049, 95% = CI 1.213–3.463, p = 0.007). p = 0.004; in addition, allele G in rs8078510 would bring higher CAD risk to the carriers who ever smoked (OR = 1.695, 95% CI = 1.080–2.660, p = 0.021). Conclusion The genetic variability of GIP gene is associated with CAD and it may play a role in the premature CAD in the Chinese Han population with type 2 diabetes.

Rs46522 in the Ubiquitin-Conjugating Enzyme E2Z Gene Is Associated with the Risk of Coronary Artery Disease in Individuals of Chinese Han Population with Type 2 Diabetes

Aims We investigated the association between ubiquitin-conjugating enzyme E2Z (UBE2Z) gene SNP rs46522 and the risk of CAD in a Chinese Han population with type 2 diabetes and explored a possible interactive effect with environmental risk factors of CAD. Methods 665 patients with T2D were enrolled; 390 were CAD patients and 275 were non-CAD patients. Genotype analysis of rs46522 (T>C) was performed using PCR-RFLP. Results The SNP rs47522 was associated with the risk of CAD supposing recessive inheritance model (TT versus CC+CT, OR′ = 1.277, 95%CI′ 1.039–1.570, p′ = 0.020) and codominant model (TT versus CT, OR′ = 1.673, 95%CI′ 1.088–2.570, p′ = 0.019) after adjustment for confounders of CAD. A synergistic effect of rs46522 and BMI was discovered (β = 0.012, p for interreaction = 0.028). In subgroup analysis, minor allele T was significantly associated with CAD in overweight and obesity subgroup (p = 0.034), and the association was also proved in recessive model (OR = 1.537, 95%CI 1.075–2.196, p = 0.018). Smokers with genotype TT had threefold risk of CAD in comparison to nonsmokers with genotype TC or CC (p < 0.001). Conclusions The SNP rs46522 in UBE2Z gene is associated with the risk of CAD in the individuals of Chinese Han descent with type 2 diabetes and is of synergistic effect with BMI.