[The appropriate cut-off point of time in range (TIR) for evaluating glucose control in type 2 diabetes mellitus]

Objective: To investigate the appropriate cut-off point of time in range (TIR) for evaluating glucose control in type 2 diabetes mellitus (T2DM) patients, and analyze the prevalence of abnormal carotid intima-media thickness (CIMT) and diabetic retinopathy (DR) in different TIR categories. Methods: A total of 2 161 subjects with T2DM (1 183 males) were enrolled from hospitalized patients at the Department of Endocrinology and Metabolism of the Sixth People's Hospital Affiliated to Shanghai Jiao Tong University from January 2005 to February 2012. The age of the enrolled participants was (60.4±11.9) years. Each patient underwent continuous glucose monitoring (CGM) for three consecutive days, then TIR (3.9-10.0 mmol/L), time above range (TAR) and time below range (TBR) were calculated. Fundus photography and carotid artery Doppler ultrasound were performed to diagnose DR and abnormal CIMT (defined as CIMT≥1.0 mm), respectively. Multivariate logistic regression models were used to examine the independent association of different TIR groups with CIMT and DR. Results: All subjects were divided into 4 groups according to TIR:≤40%, 41%-70%, 71%-85% and>85%. Significant linear trends in age, diabetes duration, body mass index (BMI), total cholesterol, glycated hemoglobin A1c (HbA1c), TAR and mean glucose (MG) existed among the 4 groups (all P(trend)<0.05). However, there was only a weak correlation between TIR and TBR (<3.9 mmol/L) (r=0.087, P<0.001), and no significant association was observed between TBR (<3 mmol/L) and the TIR categories (P(trend)=0.378). The overall prevalence of abnormal CIMT and DR was 12.1% and 23.8%, respectively. The prevalence of abnormal CIMT in the 4 groups with ascending levels of TIR was 16.9% (59/349), 12.9% (96/746), 11.2% (57/510) and 9.0% (50/556) (P(trend)<0.001), respectively. And the prevalence of DR was 30.7% (107/349), 29.4% (219/746), 20.8% (106/510) and 14.9% (83/556), respectively (P(trend)<0.001). In the binary logistic regression model by adjusting confounding factors, compared with TIR≤ 40%, the risk of abnormal CIMT was reduced by 33.8% (OR=0.662, 95%CI: 0.456-0.963, P=0.031), 40.8% (OR=0.592, 95%CI: 0.390-0.899, P=0.014), and 45.0% (OR=0.550, 95%CI: 0.358-0.846, P=0.006) in the other three groups, respectively. And the risk of DR was reduced by 2.9% (OR=0.971, 95%CI: 0.725-1.301, P=0.844), 33.4%(OR=0.666, 95%CI: 0.479-0.924, P=0.015) and 53.3% (OR=0.467, 95%CI: 0.331-0.657, P<0.001), respectively. Conclusion: Using 40%, 70% and 85% as cut-off point of TIR helps stratify the risk of diabetic complications, and assess the glucose control (Poor: TIR≤40%; Unsatisfactory: TIR≤70%; Satisfactory: TIR>70%; Optimal: TIR>85%) in patients with T2DM.

Genetic Diversity of Colletotrichum spp. Causing Strawberry Anthracnose in Zhejiang, China

Anthracnose is a serious fungal disease that primarily infects strawberry roots and stolons during development. Here, 91 isolates from different areas of Zhejiang province, China, were collected. Morphological characteristics were analyzed, and a phylogenetic analysis based on multiple genes (actin, internal transcribed spacer, calmodulin, glyceraldehyde-3-phosphate dehydrogenase, and chitin synthase) was performed. We found that all of the Colletotrichum species causing strawberry anthracnose belonged to the Colletotrichum gloeosporioides complex. Among them, we identified 48 isolates of C. fructicola, 21 isolates of C. siamense, 13 isolates of C. gloeosporioides, and 9 isolates of C. aenigma. C. siamense was distributed in the central and eastern regions of Zhejiang province (Hangzhou, Jinhua, Shaoxing, Ningbo, and Taizhou). This is the first report of C. siamense causing strawberry anthracnose in Zhejiang province. C. fructicola was the most dominant species causing strawberry anthracnose in Zhejiang province. We identified the four species causing strawberry anthracnose in Zhejiang province, which will improve our understanding of the strawberry anthracnose epidemic and will benefit the development of future control measures.

Rapid on-site evaluation of the development of resistance to quinone outside inhibitors in Botrytis cinerea

Botrytis cinerea, a typical "high-risk" pathogenic fungus that rapidly develops resistance to fungicides, affects more than 1,000 species of 586 plant genera native to most continents and causes great economic losses. Therefore, a rapid and sensitive assay of fungicide resistance development in B. cinerea populations is crucial for scientific management. In this study, we established a Loop-mediated isothermal amplification (LAMP) system for the monitoring and evaluation of the risk of development of B. cinerea resistance to QoI fungicides; the method uses two LAMP assays. The first assay detects G143A mutants of B. cinerea, which are highly resistance to QoI fungicides. BCbi143/144 introns in B. cinerea are then detected by the second assay. HNB acts as a visual LAMP reaction indicator. The optimum reaction conditions of the LAMP assays were 61 °C for 50 min, and the detection limit of the LAMP assays was 100 × 10-4 ng/μl. We directly pre-treated the field samples by using All-DNA-Fast-Out to extract DNA within ten minutes, then performed the LAMP assay to achieve one-step rapid detection. In conclusion, we established a rapid and sensitive LAMP assay system for resistance risk assessment and for monitoring QoI-resistance of B. cinerea in the field.

Positive association between PPARD rs2016520 polymorphism and coronary heart disease in a Han Chinese population

PPARD encodes peroxisome proliferator-activated re-ceptor delta, which has been shown to play an important role in control-ling lipid metabolism and atherosclerosis. In this case-control study, we explored the relationship between PPARD rs2016520 polymorphism and coronary heart disease (CHD) in a Han Chinese population. A to-tal of 657 CHD cases and 640 controls were included in the associa-tion study. rs2016520 polymorphism genotyping was performed using the melting temperature-shift polymerase chain reaction method. The PPARD rs2016520-G allele reduced CHD risk by 17.9% (χ(2) = 5.061, P = 0.025, OR = 0.821, 95%CI = 0.692-0.975). Furthermore, a signifi-cant difference in CHD risk was observed for the PPARD rs2016520 polymorphism in the dominant model (AG + GG vs AA: χ(2) = 4.751, degrees of freedom (df) = 1, P = 0.029, OR = 0.784, 95%CI = 0.631- 0.976). Analysis by age suggested that the G-allele decreased CHD risk by 14.8% in ages greater than 65 years (χ(2) = 4.446, P = 0.035, OR = 0.852, 95%CI = 0.684-1.060). In contrast, meta-analysis of PPARD rs2016520 among 3732 cases and 5042 controls revealed no associa-tion between PPARD rs2016520 and CHD (P = 0.19). We found that the PPARD rs2016520-GG genotype decreased CHD risk in a Han Chinese population. Moreover, we found an association between serum high-density lipoprotein cholesterol level and PPARD rs2016520 in senior individuals aged ≥ 65 years. The meta-analysis revealed no association between PPARD rs2016520 and CHD, suggesting ethnic differences in the association between the PPARD locus and CHD.

Effect of lentivirus-mediated shRNA targeting VEGFR-3 on proliferation, apoptosis and invasion of gastric cancer cells

It has been reported that vascular endothelial growth factor receptor 3 (VEGFR-3) is highly expressed in most tumor tissues, including gastric cancer. However, the effects of VEGFR-3 knockdown on the proliferation, apoptosis and invasion of gastric cancer cells and downstream signaling molecules have not yet been well established. In the present study, four short hairpin RNA (shRNA) sequences targeting the VEGFR-3 gene (NM_002020) were designed and cloned into a lentiviral vector, pRNAT-U6.2/Lenti, to construct four recombinant lentiviral vectors. The vectors with the two highest interfering efficiencies were selected to be co-transfected with packaging vectors in HEK293T cells to assemble lentivirus particles. Results from Western blot analysis showed that the VEGFR-3 shRNA-4 lentivirus-infected group (sh#4) had the highest efficiency of gene silencing in the MKN45 cell line compared with the parental and control group. The sh#4 group significantly slowed cell proliferation, decreased the mean percentage of S-phase cells and increased the mean percentage of G1 phase cells, promoted cell apoptosis, and also significantly inhibited cell invasion of MKN45 compared with the other two groups. Furthermore, the expression of the anti-apoptotic factor Bcl-2 was significantly decreased in the sh#4 group compared to that of the other two groups. Moreover, results from qRT-PCR revealed that knockdown of VEGFR-3 with the shRNA lentiviral vector resulted in down-regulation of the downstream neural cell adhesion molecule contactin-1 (CNTN-1). In conclusion, the recombinant lentivirus particles were able to remarkably suppress VEGFR-3 expression, regulate the cell cycle, inhibit proliferation and induce apoptosis in the MKN45 cell lines.

Chemoresponse to docetaxel correlates with expression of the survivin splicing variants in patients with gastric cancer

BACKGROUND/AIMS

Survivin, a potential predictive marker to chemotherapeutic drugs, reduces the susceptibility of tumor cells to proapoptotic stimuli, thereby promoting tumor cell survival during tumor treatment with anticancer agents. In the present study, we examined the correlation between drug-response and expression of survivin in gastric cancer.

METHODOLOGY

Drug-response was performed by histoculture drug-response assay (HDRA) in 42 patients with advanced gastric cancer. Survivin variants was studied by real-time RT-PCR at mRNA levels.

RESULTS

In our data, twenty-one cases (50%) were sensitive to at least one of drugs tested in the HDRA and 80% (16/20) were positively confirmed clinically, with 100% sensitivity and 83.3% specificity. The diagnostic efficacy of the HDRA were calculated as the area under the receiver operating characteristic (AUC-ROC) curve and showed a value of 0.917. More importantly, significant statistical differences (p=0.012) in chemoresponse to docetaxel were revealed depending on the mRNA level of wild-type survivin.

CONCLUSIONS

These clinical data demonstrated, for the first time, that wild-type survivin is useful for evaluating the docetaxel-response in patients with gastric cancer. Moreover, the HDRA is an excellent clinical useful drug-response assay for patients to individualize their chemotherapy.

[Effect of inhibiting survivin expression with antisense oligodeoxynucleotides on sensitivity of hepatocellular carcinoma cell lines HepG2 and HepG2/ADM to adriamycin]

BACKGROUND & OBJECTIVE

Survivin deserves attention as a selective target for cancer therapy because it is silenced in differentiated adult tissues, but is expressed in a variety of human tumors, and is involved in tumorigenesis and chemoresistance. Antisense oligodeoxynucleotides (ASODN) can be used to inhibit the expression of survivin to induce apoptosis or enhance chemosensitivity of tumor cells. This study was to investigate the effect of inhibiting survivin expression with ASODN on sensitivity of hepatocellular carcinoma cell lines HepG2 and HepG2/ADM to Adriamycin (ADM).

METHODS

The expression of survivin in HepG2 and HepG2/ADM cells was detected by reverse transcription-polymerase chain reaction (RT-PCR) and Western blot. Sensitivities of HepG2 and HepG2/ADM cells to ASODN and ADM were detected by MTT assay. ASODN was transfected into HepG2 and HepG2/ADM cells; expression of survivin was detected by RT-PCR. Synergetic effects of low concentrations of ASODN and subtoxic concentrations of ADM on HepG2 and HepG2/ADM cells were detected by isobolography. The expression of active Caspase-3 and cell apoptosis were evaluated by flow cytometry.

RESULTS

mRNA level of survivin in HepG2/ADM cells was 15 folds as that in HepG2 cells; protein level of Survivin in HepG2/ADM cells was 18 folds as that in HepG2 cells. Both HepG2 and HepG2/ADM cells were sensitive to ASODN-mediated cytotoxicity in a concentration-dependent manner. The 50% inhibitory concentration (IC(50)) of ASODN was 317.90 nmol/L for HepG2 cells, and 480.74 nmol/L for HepG2/ADM cells. The maximal cytotoxicity was observed at 500 nmol/L of ASODN; the inhibitory rate was 71.10% in HepG2 cells, and 53.67% in HepG2/ADM cells. The IC(50) of ADM was 0.36 microg/ml for HepG2 cells, and 2.12 microg/ml for HepG2/ADM cells; the resistance index was 6. ASODN efficiently down-regulated mRNA level of survivin in both cell lines in a concentration-dependent manner. For HepG2 cells, with the IC(50) of 271.93 nmol/L, the maximal effect of ASODN was achieved at a concentration of 400 nmol/L, at which mRNA level of survivin was down-regulated by 69.12%; for HepG2/ADM cells, with the IC(50) of 365.72 nmol/L, its maximal effect was achieved at a concentration of 400 nmol/L, at which mRNA level of survivin was down-regulated by 60.01%. ASODN in combination with ADM synergetically enhanced sensitivity of HepG2 cells to ADM by 6 folds, and HepG2/ADM cells by 4 folds. Combination treatment of ASODN and ADM gradually enhanced activity of Caspase-3 and cell apoptosis in a concentration-dependent manner, and resulted in caspase-dependent cell death in HepG2/ADM cells.

CONCLUSION

Inhibiting survivin expression with ASODN could sensitize hepatocellular carcinoma cells to ADM, and the combination of ASODN and ADM may be a reasonable approach for clinical treatment of ADM-resistant hepatocellular carcinoma.

Survivin antisense compound inhibits proliferation and promotes apoptosis in liver cancer cells

AIM: To evaluate the effects of survivin on cell proliferation and apoptosis in liver cancer.

METHODS: MTT assay was used to generate and optimize phosphorothioate antisense oligonucleotides (ODNs)-Lipofectamine^TM2000 (LiP) compound by varying ODNs (μg):LiP (μL) ratios from 1:0.5 to 1:5. Then, liver cancer cells (HepG₂) were transfected with the compound. By using RT-PCR and Western blot, the expression levels of survivin mRNA and proteins were detected in HepG₂ cells treated with antisense compounds (ODNs:LiP = 1:4), and compared with those treated with sense compounds (1:4) as control. MTT assay was applied to the determination of cell proliferation in HepG₂ cells. Active caspase-3 was evaluated by flow cytometric analysis. The morphological changes were assessed by electron microscopy. Laser scanning confocal microscopy was performed to detect the subcellular localization of survivin proteins in treated and untreated cells.

RESULTS: Antisense compounds (1:4) down-regulated survivin expression (mRNA and protein) in a dose-dependent manner with an IC₅₀ of 250 nmol/L. Its maximum effect was achieved at a concentration of 500 nmol/L, at which mRNA and protein levels were down-regulated by 80%. The similar results were found in MTT assay. Antisense compound (1:4)-treated cells revealed increased caspase-3-like protease activity compared with untreated cells. Untreated cells as control were primarily negative for the presence of active-caspase-3. As shown by transmission electron microscopy, treated cells with antisense compounds (1:4) resulted in morphological changes such as blebbing and loss of microvilli, vacuolization in the cytoplasm, condensation of the cytoplasm and nuclei, and fragmented chromatin. Immunofluorescence analysis confirmed the presence of survivin protein pool inside the cytoplasm in untreated cells. Labeled-FITC immunofluorescence staining of survivin clearly showed that survivin was distributed mainly in a spotted form inside the cytoplasm. Whereas cells treated with antisense compounds were rare and weak inside the cytoplasm.

CONCLUSION: Down-regulation of survivin expression induced by the antisense compounds reduces tumor growth potential, promotes apoptosis and affects the localization of survivin proteins in HepG₂ cells. Furthermore, survivin protein is a key molecule associated with proliferation and apoptosis, and antisense oligonucleotides targeting survivin have a bright prospect in the therapy of liver cancer.

Expression level of wild-type survivin in gastric cancer is an independent predictor of survival

AIM: Survivin is a novel antiapoptotic gene in which three splicing variants have been recently cloned and characterized. Survivin has been found to be abundantly expressed in a wide variety of human malignancies, whereas it is undetectable in normal adult tissues. We aimed to study the expression of three survivin splicing variants in gastric cancer, and to evaluate the prognostic significance of the expression of survivin variants in gastric cancer.

METHODS: Real time quantitative RT-PCR was performed to analyze the expression of survivin variants in 79 paired tumors and normal gastric mucosa samples at the mRNA level. Proliferative and apoptotic activity was measured using Ki-67 immunohistochemical analysis and the TUNEL method, respectively.

RESULTS: All the cases tested expressed wild-type survivin mRNA, which was not only the dominant transcript, but also a poor prognostic biomarker (P = 0.003). Non-antiapoptostic survivin-2B mRNA was correlated with tumor stage (P = 0.001), histological type (P = 0.004), and depth of tumor invasion (P = 0.041), while survivin-△Ex3 mRNA showed a significant association with apoptosis (P = 0.02).

CONCLUSION: Wild-type survivin mRNA expression levels are of important prognostic value and significant participation of survivin-2B and survivin-△Ex3 is suggested in gastric cancer development.

Effects of daidzein on estrogen-receptor-positive and negative pancreatic cancer cells in vitro

AIM: To study the effects of daidzein on human pancreatic cancer cells in vitro.

METHODS: Human estrogen-receptor (ER)-positive pancreatic cancer cells MiaPaCa-2 and ER-negative pancreatic cancer cells PANC-1 were treated by 0.1 μmol/L, 1 μmol/L, 10 μmol/L, 25 μmol/L, 50 μmol/L, 75 μmol/L and 100 μmol/L of daidzein, respectively. Its antiproliferative effect was studied by MTT assay.

RESULTS: Daidzein inhibited the growth of MiaPaCa-2 and PANC-1 cells at the concentrations from 0.1 μmol/L to 100 μmol/L. A dose- and time-dependent manner was found. The IC₅₀ of daidzein on MiaPaCa-2 and PANC-1 cells was 45 μmol/L and 75 μmol/L, respectively. After MiaPaCa-2 cells were treated by daidzein for 3 d and at the concentrations more than IC₅₀, the inhibitory manner was identical and the inhibition appeared a saturation phenomenon, but the inhibitory manner of daidzein on PANC-1 cells was different from that of MiaPaCa-2 cells.

CONCLUSION: Daidzein has antiproliferative effects on human estrogen-receptor-positive and negative pancreatic cancer cells, but their mechanisms may be different.

[Effect of acute hypobaric hypoxia on renal function and structure in rats]

OBJECTIVE

To observe renal damage due to acute hypobaric hypoxia.

METHOD

Thirty-six male wistar rats were randomly divided into three groups A, B and C (n = 12 for each). Group A served as control, while groups B and C were exposed to 5000 m altitude for 30 min. Sample of serum and renal tissues were taken from group B rats 20 min and from group C rats 24 h after the exposure respectively.

RESULT

Serum ureanitrogen (BUN) and creatinine (Crea) increased significantly in group B and C rats after exposure to hypoxia (P< 0.01). Cl- and alkaline phosphatase (AKP) in serum also increased (P < 0.05), but renal endothelin (ET) decreased significantly (P < 0.01). All changes in group C rats tended to recover to normal level, except Cl- which continued to increase. Dilation of renal vessels was found under optic-microscope, and pathological changes were found in mitochondra and epithelial cells.

CONCLUSION

Acute hypobaric hypoxia might be harmful to renal function and structure.

[Relation of GFR and endothelin in the plasma in pilots and ground crew]

OBJECTIVE

To observe the specitic property of Glomeoular Filtration Rate (GFR) and its relation to endothelin of plasma in pilots.

METHOD

GFR was assessed with single photon emisson computed tomography (SPECT), tracer for 99mTc-DTPA, enthlion of plasma were measured by radio immunossay in forty-six pilots, thirty ground crew and renal disease patients.

RESULT

Endothelin were not correlation with GFR in pilots. GFR of pilots and ground crew had not a significant difference. Compared with ground crew and pilots, endothelin of renal disease patients had a significant increased, and GFR had a significant decreased. Age were a linear negative correlation with total GFR r = (0.84, P < 0.01), flying time, age had not correlation with endothelin. After thirty-one ground endothelin had a significant difference with ground crew.

CONCLUSION

It suggested that the endothelin has no influence on GFR in pilots when it was increased with in the limits of a level, pilots and ground crew may use the same stand on GFR.