Efficacy and tolerability of vildagliptin as add-on therapy to metformin in Chinese patients with type 2 diabetes mellitus

AIM

To investigate the efficacy and tolerability of vildagliptin as add-on therapy to metformin in Chinese patients with type 2 diabetes mellitus (T2DM) inadequately controlled with metformin.

METHODS

This was a 24-week, randomized, double-blind, placebo-controlled study. Patients with T2DM (N = 438) with haemoglobin A1c (HbA1c) of 7.0-10.0% and fasting plasma glucose (FPG) <15 mmol/l (<270 mg/dl) were randomized (1 : 1 : 1) to vildagliptin 50 mg bid, vildagliptin 50 mg qd or placebo in addition to metformin.

RESULTS

The treatment groups were well balanced at baseline [mean HbA1c, 8.0%, FPG, 8.8 mmol/l (158 mg/dl); body mass index, 25.5 kg/m(2) ]. The adjusted mean change (AMΔ) in HbA1c at endpoint was -1.05 ± 0.08%, -0.92 ± 0.08% and -0.54 ± 0.08% in patients receiving vildagliptin 50 mg bid, 50 mg qd and placebo, respectively. The between-treatment difference (vildagliptin 50 mg bid-placebo) was -0.51 ± 0.11%, p < 0.001. A greater proportion of vildagliptin-treated patients met at least one responder criterion (82.1 and 70.7%) compared to placebo-treated patients (60.4%). The AMΔ at endpoint for FPG with vildagliptin 50 mg bid, -0.95 mmol/l (-17.1 mg/dl); 50 mg qd, -0.84 mmol/l (-15.1 mg/dl) was significantly different compared with the placebo -0.26 mmol/l (-4.68 mg/dl) (p ≤ 0.001). Adverse events (AEs) were reported as 34.2, 36.5 and 37.5% for patients receiving vildagliptin 50 mg bid, 50 mg qd or placebo, respectively. Two patients in the vildagliptin 50 mg qd and one in the placebo group reported serious AEs, which were not considered to be related to the study drug; one incidence of hypoglycaemic event was reported in the vildagliptin 50 mg bid group.

CONCLUSION

Vildagliptin as add-on therapy to metformin improved glycaemic control and was well tolerated in Chinese patients who were inadequately controlled by metformin only.

Pump-to-Stokes relative intensity noise transfer and analytical modeling of mid-infrared silicon Raman lasers

An analytical model for mid-infrared (mid-IR) silicon Raman lasers (SRLs) is developed. The relative intensity noise (RIN) transfer from the pump to the Stokes in the lasers is also investigated. The analytical model can be used as a versatile and efficient tool for analysis, design and optimization of mid-IR SRLs. It is shown that conversion efficiency of 70% is attainable and the low-frequency RIN transfer may be suppressed to below 1 dB by pumping low-loss waveguides at high intensities.

Cigarette smoking extract causes hypermethylation and inactivation of WWOX gene in T-24 human bladder cancer cells

Genomic, epigenetic and expression alterations of WW domain containing oxidoreductase (WWOX) have been implicated in multiple tumor types. The current study was designed to examine the expression of WWOX in tumor tissues of human bladder transitional cell carcinoma (BTCC) and the influence of cigarette smoke extract (CSE) on WWOX expression and methylation status in T-24 bladder cancer cells. WWOX protein expression was evaluated by immunohistochemistry staining in a series of tumor samples from 78 patients with BTCC and 26 normal bladder tissues. The expression level and methylation status of WWOX in CSE-treated cells were examined by using quantitative Real-Time RT-PCR and methylation specific PCR, respectively. The expression levels of DNA methyltransferases (DNMTs) 1, 3A and 3B were also detected. We found that WWOX expression was absent or reduced in 79.5% (62/78) of BTCC tissues, but only in 19.2% (5/26) of normal bladder tissues. Loss of WWOX expression was correlated with tumor grade (P=0.019) and cigarette smoking (P=0.031), but was not associated with age, gender, tumor size and tumor number. Hypermethylation of WWOX promoter and exon 1 was specifically induced by CSE with a kinetics concurrent to the suppression of WWOX mRNA in T-24 cells. Furthermore, CSE treatment induced a significant time-dependent increase in the level of DNMT1, but has no effects on DNMT3A and DNMT3B. Taken together, these novel findings suggest that hypermethylation of WWOX induced by cigarette smoking may represent one underlying mechanism for the loss expression of WWOX in bladder cancer.

Combination of valproic acid and ATRA restores RARβ2 expression and induces differentiation in cervical cancer through the PI3K/Akt pathway

Epigenetic silencing of the tumor suppressor gene, RARβ2, through histone deacetylation has been established as an important process of cervical carcinogenesis. This pivotal role has led to the suggestion that a combination of retinoids selective for RARβ2 with histone deacetylase (HDAC) inhibitors may have therapeutic potential. Valproic acid (VPA), a HDAC inhibitor, has a critical role in the regulation of gene expression through histone acetylation and causes transformed cells to undergo growth arrest, differentiation, and apoptosis. Therefore, we hypothesized that the combination of VPA and ATRA could restore RARβ2 expression, thus resulting in enhanced anti-neoplastic activity in cervical cancer. Here, we show that VPA combined with ATRA led to hyperacetylation of histone H3 and a significant alteration of gene expression in cervical cancer cells, including RARβ2 gene expression, which was upregulated 50- to 90-fold. The combination therapy effectively inhibited the growth of cervical cancer cells more than the single agent treatment both in vitro and in vivo. The additive effects were associated with a significant upregulation of p21(CIP1) and p53 as well as a pronounced decrease in p-Stat3. Furthermore, the combined treatment led to cell cycle arrest predominantly at the G1 phase, and it preferentially induced cell differentiation rather than apoptosis in cervical cancer cells. The differentiation program was determined by the presence of E-cadherinmediated adhesion and activation of the PI3K/Akt pathway. Taken together, these results provide new insight into the mechanisms of enhanced antitumor activity of the HDAC inhibitor and ATRA regimen, thus offering a new therapeutic strategy for cervical cancer patients.

The role of male chromosomal polymorphism played in spermatogenesis and the outcome of IVF/ICSI-ET treatment

Chromosomal polymorphism has been reported to be associated with infertility, but its effect on IVF/ICSI-ET outcome is still controversial. To evaluate whether or not chromosomal polymorphism in men plays a role in spermatogenesis and the outcome of IVF/ICSI-ET, we retrospectively analysed 281 infertile couples. Measures included fertilization rate, implantation rate, pregnancy rate, clinical pregnancy rate, ongoing pregnancy rate, early miscarriage rate and preterm rate. Men with chromosomal polymorphism had significantly higher frequencies of severe oligozoospermia and azoospermia than those without (37.12% vs. 16.11%, p < 0.001; 27.27% vs. 10.74%, p < 0.001; respectively). Significantly, lower fertilization rate (68.02% vs. 78.00%, p < 0.001) and clinical pregnancy rate (45.00% vs. 66.67%, p = 0.031) were observed in polymorphism-carrying men with severe oligozoospermia compared with non-carriers with severe oligozoospermia. This suggests that chromosomal polymorphism has adverse effects on spermatogenesis, negatively influencing the outcome of IVF/ICSI-ET treatment. Polymorphic variations on the Y chromosome have been found to be the most prevalent polymorphism in infertile men, most frequently occurring in patients with severe oligozoospermia.

Treatment of post-traumatic carotid-cavernous fistulas with the Willis covered stent. A preliminary prospective study

We describe our preliminary experience on the feasibility of using the Willis covered stent in patients with carotid-cavernous fistulas (CCFs). Eleven consecutive patients with post-traumatic CCFs referred for treatment with Willis covered stents were enrolled into this prospective study, and were subsequently followed-up at our hospital. Data on technical success, initial and final angiographic results, mortality, morbidity and final clinical outcome, was collected, with follow-up performed at one, three, six and 12 months, and yearly thereafter. Deployment of the covered stents was technically successful in all patients. Angiographic results following stent placement showed a complete occlusion in eight patients with ten CCFs, and an incomplete occlusion in three. No adverse events occurred either during or after the procedure. Angiographic follow-up (mean 14.73 ± 6.77 months) revealed complete occlusion and no obvious in-stent stenosis in all patients. Clinical follow-up (mean 17.73 ± 6.48 months) demonstrated full recovery in ten patients, and improvement in one. These preliminary results indicate that the use of the Willis covered stent is a feasible procedure, and that it may therefore serve as an alternative treatment for CCFs. Longer follow-up assessments and an expanded clinical trial are needed.

MicroRNA-337 is associated with chondrogenesis through regulating TGFBR2 expression

OBJECTIVE

MicroRNAs (miRNAs) have been implicated in regulating diverse cellular pathways and involved in development and inflammation. This study aimed to examine six miRNAs expression during the cartilage development and identify the key miRNA which is associated with chondrogenesis.

METHODS

The expression of six miRNAs in cartilage tissue during development was screened by real-time quantitative polymerase chain reaction (RT-qPCR). Rat models of bone matrix gelatin induced endochondral ossification, collagen-induced arthritis and pristane-induced arthritis were established to examine whether miR-337 is involved in chondrogenesis. Furthermore, the regulation of transforming growth factor-b type II receptor (TGFBR2) expression by miR-337 was determined with the luciferase reporter gene assay and Western blot. The expression of some specific genes relevant to cartilage tissue was tested by RT-qPCR after miR-337 mimic or inhibitor transfection.

RESULTS

MiR-337 expression was significantly down-regulated and almost disappeared in the maturation phases of endochondral ossification. The results of histology and RT-qPCR from three rat models showed that miR-337 is directly bound up with chondrogenesis. Furthermore, the results from the luciferase reporter gene assay and Western blot indicated that miR-337 regulated TGFBR2 expression. Our study also found that the enhancement of miR-337 may modulate the expression of cartilage-specific genes such as AGC1 in C-28/I2 chondrocytes.

CONCLUSION

We proved that miRNA-337 is associated with chondrogenesis through regulating TGFBR2 expression, and miRNA-337 can also influence cartilage-specific gene expression in chondrocytes. These findings may provide an important clue for further research in the arthritis pathogenesis and suggest a new remedy for arthritis treatment.

Graphene mode-locked femtosecond laser at 2 μm wavelength

We experimentally demonstrated a passively mode-locked femtosecond laser by using a graphene-based saturable absorber mirror (graphene SAM) in the spectral region of 2 μm. The graphene SAM was fabricated by transferring chemical-vapor-deposited, high-quality, and large-area graphene on a highly reflective plane mirror. Stable mode-locked laser pulses as short as 729 fs were obtained with a repetition rate of 98.7 MHz and an average output power of 60.2 mW at 2018 nm.

Fine structure analysis and sintering properties of Si-doped hydroxyapatite

Si-doped hydroxyapatite (Si-HA) has been intensively investigated as a promising bone biomaterial because of the biomineralization and bone formation benefit from silicon addition. In the current work, Si-HA samples were synthesized by the aqueous precipitation method. The sintering property of Si-HA was studied in terms of phase composition and transition, which was influenced by the Si doping percentage and sintering temperature. The results indicate that all the as-prepared and sintered low Si doping samples (Si% ≤ 1.6 wt%) possess HA phases; while the high Si doping samples (Si% ≥ 2 wt%) present amorphous phases as prepared, and largely or even completely transform to β-tricalcium phosphate (β-TCP) phase after sintering at 1250 °C. The Rietveld refinement on x-ray diffraction patterns was conducted to determine the particle sizes, microstrain factors and anisotropic distributions. According to the refined results, the calculated anisotropic particle sizes correspond to the observations made by transmission electron microscopy. The microstrains also present anisotropic distributions in all refinements. The accurate variation in the fine structure of Si-HA has been studied by the improved refinements after considering the anisotropic distribution.

Large intervening non-coding RNA HOTAIR is associated with hepatocellular carcinoma progression

Increasing evidence suggests that large intervening non-coding RNAs (lincRNAs) regulate key pathways in cancer invasion and metastasis. In this observational retrospective study, the expression of the oncogenic lincRNA HOX transcript antisense RNA (HOTAIR) gene was measured in 63 patients with hepatocellular carcinoma (HCC) following hepatic resection. The HOTAIR gene was significantly overexpressed in HCC tissues compared with adjacent non-tumour tissues. Patients with high HOTAIR gene expression in their tumours had an increased risk of recurrence after hepatectomy. There was also a significant correlation between HOTAIR expression and lymph node metastasis. In vitro assays in the HCC cell line Bel7402 demonstrated that knockdown of HOTAIR lincRNA reduced cell proliferation and was associated with reductions in levels of matrix metalloproteinase-9 and vascular endothelial growth factor protein, which are important for cell motility and metastasis. In conclusion, HOTAIR lincRNA might be a potential biomarker for the existence of lymph node metastasis in HCC.

Effects of variations in duodenal glucose load on glycaemic, insulin, and incretin responses in type 2 diabetes

AIMS

Postprandial glucagon-like peptide-1 (GLP-1) secretion and the 'incretin effect' have been reported to be deficient in Type 2 diabetes, but most studies have not controlled for variations in the rate of gastric emptying. We evaluated blood glucose, and plasma insulin, GLP-1 and glucose-dependent insulinotropic polypeptide (GIP) responses to intraduodenal glucose in Type 2 diabetes, and compared these with data from healthy controls.

METHODS

Eight males with well-controlled Type 2 diabetes, managed by diet alone, were studied on four occasions in single-blind, randomized order. Blood glucose, and plasma insulin, GLP-1, and GIP were measured during 120-min intraduodenal glucose infusions at 1 kcal/min (G1), 2 kcal/min (G2) and 4 kcal/min (G4) or saline control.

RESULTS

Type 2 patients had higher basal (P < 0.0005) and incremental (P < 0.0005) blood glucose responses to G2 and G4, when compared with healthy controls. In both groups, the stimulation of insulin and GLP-1 by increasing glucose loads was not linear; responses to G1 and G2 were minimal, whereas responses to G4 were much greater (P < 0.005 for each) (incremental area under the GLP-1 curve 224 ± 65, 756 ± 331 and 2807 ± 473 pmol/l.min, respectively, in Type 2 patients and 373 ± 231, 505 ± 161 and 1742 ± 456 pmol/l.min, respectively, in healthy controls). The GLP-1 responses appeared comparable in the two groups. In both groups there was a load-dependent increase in plasma GIP with no difference between them.

CONCLUSIONS

In patients with well-controlled Type 2 diabetes, blood glucose, insulin and GLP-1 responses are critically dependent on the small intestinal glucose load, and GLP-1 responses are not deficient.

Single- and double-SSR primer combined analyses in rice

Polymerase chain reaction (PCR) is the foundation of SSR molecular marker technology. We used sib rice varieties J518, XD1 and SD23 as experimental materials, selecting 30 pairs of SSR primers, including RM127, RM337 and RM5172, covering the rice genome, and performed single- and double-SSR primer combined analyses. We found that under the same PCR system and conditions, a single primer of the SSR primer pairs could amplify the same fragments as double primers do. The sequencing results demonstrated that some amplified fragments that we previously believed to come from double primers were actually produced by a single primer. The use of this kind of primer, such as the RM127 primer pair, for marker-assisted breeding will therefore be misleading. Additionally, using the same PCR system and conditions, some single primers that are part of SSR primer pairs can amplify many more specific fragments than double-SSR primers. For instance, in the case of the RM5172 primer pair, a single primer P1 amplified approximately three times the number of fragments as the double primer. This information can contribute to research on genetic diversity of species, understanding of genetic relationships and identification of germplasm resources. Accordingly, combined analyses of single- and double-primer amplification products not only can remove single-primer amplification fragments and false-positives from double-primer amplification products in order to improve test accuracy, but also can facilitate research on genetic diversity, exploration of phylogenetic relationships and identification of germplasm resources. We define this method as "single- and double-SSR primer combined analyses".

Diode-pumped mode-locked femtosecond Tm:CLNGG disordered crystal laser

A diode-end-pumped passively mode-locked femtosecond Tm-doped calcium lithium niobium gallium garnet (Tm:CLNGG) disordered crystal laser was demonstrated for the first time to our knowledge. With a 790 nm laser diode pumping, stable CW mode-locking operation was obtained by using a semiconductor saturable absorber mirror. The disordered crystal laser generated mode-locked pulses as short as 479 fs, with an average output power of 288 mW, and repetition rate of 99 MHz in 2 μm spectral region.

rDNA ITS sequences among morphotypes of Keratell cochlearis, Keratell quadrata and Brachionus forficula (Rotifera)

Morphological variation in rotifers is affected by environmental conditions, making it hard to identify some rotifer taxa. We examined the rDNA ITS sequences of 10 unspined (KCU1-KCU10) and 17 spined (KCS1-KCS17) Keratell cochlearis clones, 26 two-spined (KQT1-KQT26), 18 single-spined (KQS1-KQS18) and 9 unspined (KQU1-KQU9) K. quadrata clones, and 17 long-spined (BL1-BL17) and 11 short-spined (BS1-BS11) Brachionus forficula clones collected from Lake Tingtang in Wuhu city, China. Molecular phylogenetic trees were constructed by neighbor-joining, maximum-likelihood, maximum parsimony, and Bayesian inference methods using B. calyciflorus as an outgroup. The K. cochlearis clones included 20 haplotypes, the K. quadrata clones included 37 haplotypes, and the B. forficula clones included 25 haplotypes. Different morphotypes of each rotifer species had shared haplotypes. Sequence divergences were 0.1-8.9% among different K. cochlearis haplotypes, and 8.1-8.9% between KCHAP1 (KCU1 and KCU10), KCU3, KCU4 and KCU6, and the other haplotypes. Sequence divergences were 0.1-14.5% among different K. quadrata haplotypes, and 11.9-14.5% between KQS17 and the other haplotypes. Sequence divergences were 0.1-11.7% among different B. forficula haplotypes, 11.0-11.7% between BL15 and the other haplotypes, 9.3-10.1% between BS3 and the other haplotypes, and 11.7% between BL15 and BS3. The four phylogenetic trees all supported that KCHAP1, KCU3, KCU4, KCU6 and the other 16 haplotypes among the 20 K. cochlearis haplotypes, KQS17 and the other 36 haplotypes among the 37 K. quadrata haplotypes, and BL15, BS3 and the other 23 haplotypes among the 25 B. forficula haplotypes all belonged to their own isolated clades. The morphological variation of the three rotifer species was attributed mainly to phenotypic plasticity.

Highly efficient 2 μm Tm:YAG ceramic laser

We have experimentally demonstrated a highly efficient diode-pumped Tm:YAG ceramic laser operating at 2 μm wavelength. The maximum output power of 6.05 W was realized with a slope efficiency as high as 65%. As far as we know, it is the highest slope efficiency reported for Tm:YAG ceramic laser. The wavelength tuning experiment of Tm:YAG ceramic laser was carried out and the results suggest that Tm:YAG ceramic laser could operate simultaneously at multiple wavelengths in a wide range of 1884-2017 nm.

Detection of quantitative trait loci for growth- and fatness-related traits in a large-scale White Duroc × Erhualian intercross pig population

Growth and fatness are economically important traits in pigs. In this study, a genome scan was performed to detect quantitative trait loci (QTL) for 14 growth and fatness traits related to body weight, backfat thickness and fat weight in a large-scale White Duroc × Erhualian F(2) intercross. A total of 76 genome-wide significant QTL were mapped to 16 chromosomes. The most significant QTL was found on pig chromosome (SSC) 7 for fatness with unexpectedly small confidence intervals of ∼2 cM, providing an excellent starting point to identify causal variants. Common QTL for both fatness and growth traits were found on SSC4, 5, 7 and 8, and shared QTL for fat deposition were detected on SSC1, 2 and X. Time-series analysis of QTL for body weight at six growth stages revealed the continuously significant effects of the QTL on SSC4 at the fattening period and the temporal-specific expression of the QTL on SSC7 at the foetus and fattening stages. For fatness traits, Chinese Erhualian alleles were associated with increased fat deposition except that at the major QTL on SSC7. For growth traits, most of White Duroc alleles enhanced growth rates except for those at three significant QTL on SSC6, 7 and 9. The results confirmed many previously reported QTL and also detected novel QTL, revealing the complexity of the genetic basis of growth and fatness in pigs.

Does 6% hydroxyethyl starch 130/0.4 impact differently on blood glucose than 4% gelatin in patients receiving open heart surgery?

Objectives: To investigate whether starch-based colloid may impact differently on blood glucose than a gelatin-based colloid in adult patients receiving open heart surgery.

Methods: 70 adult patients scheduled for elective first-time cardiac surgery were enrolled and randomized into two groups. The circuits were primed with either 6% HES 130/0.4 or 4% gelatin. The peak glucose level, incidence of hyperglycemia, glucose variation and glucose level at different time points during operation were compared between the two groups. A p-value ≤ 0.05 was accepted as significant.

Results: The peak glucose (150±30mg/dl vs 142±27, p=0.236) and glucose variation demonstrated by standard deviation (26±12mg/dl vs 23±11mg/dl, p=0.202) were comparable between the two groups. Repeated measurement ANOVA revealed that the main effect for artificial colloid was not significant (p=0.349).

Conclusions: With the data available, we could not prove that starch-based colloid (HES130) had a different impact on intra-operative blood glucose than a gelatin-based colloid in adult patients receiving open heart surgery.

Domain-based assays of individual antibody concentrations in an oligoclonal combination targeting a single protein

Quantitation of individual monoclonal antibodies (mAbs) within a combined antibody drug product is required for preclinical and clinical drug development, including pharmacokinetic (PK), toxicology, stability, and biochemical characterization studies of such drugs. We have developed an antitoxin, XOMA 3AB, consisting of three recombinant mAbs that potently neutralize the known subtypes of type A botulinum neurotoxin (BoNT/A). The three mAbs bind nonoverlapping BoNT/A epitopes with high affinity. XOMA 3AB is being developed as a treatment for botulism resulting from BoNT/A. To develop antibody-specific assays, we cloned, expressed, and purified BoNT/A domains from Escherichia coli. Each mAb bound only to its specific domain with affinity comparable to the binding to holotoxin. mAb-specific domains were used to develop an enzyme-linked immunosorbent assay (ELISA) for characterization of the integrity and binding activity of the three mAbs in the drug product. An electrochemiluminescence bridging assay that is robust to interference from components in serum was also developed, and we demonstrate that it can be used for PK assays. This type of antigen engineering to generate mAb-specific domains is a general method allowing quantitation and characterization of individual mAbs in a mAb cocktail that binds the same protein and is superior to anti-idiotype approaches.