Enhanced differentiation of human adipose tissue-derived stromal cells into insulin-producing cells with glucagon-like peptide-1

Type 1 diabetes mellitus (T1DM) is mainly caused by reduction of the endogenous insulin secretion due to autoimmune destruction of pancreatic β cells, and a promising therapeutic approach for T1DM is pancreas and islet cell replacement. The major obstacle is the limited source of insulin-producing cells. Here, we report an efficient approach to induce human adipose-derived stromal cells (hADSCs) to differentiate into insulin-producing cells, with glucagon-like peptide-1 (GLP-1). hADSCs were successfully isolated from the adipose tissue, with adipogenic and osteogenic differentiation potency. Islet-like cell clusters formed in the culture, which was enhanced with the treatment of GLP-1. Reverse transcription polymerase chain reaction analysis showed the expression of the pancreas-related genes in the differentiated cells, such as pdx-1, ngn3, insulin, glucagon, somatostatin, glucokinase n and glut2. Immunocytochemical analysis showed that the induced cells co-expressed insulin, C-peptide and PDX-1. The GLP-1 receptor was present in the differentiated cells. In addition, flow cytometry analysis and ELISA showed that, in the presence of GLP-1, the percentage of insulin-producing cells was increased from 5.9% to 28.0% and the release of insulin increased from 9.53±0.7 pmol/106 cells to 15.86±1.3 pmol/106 cells. Insulin was released in response to glucose stimulation in a manner comparable to that of adult human islets. These results indicated that hADSCs isolated from adipose tissues can be induced to differentiate into insulin-producing cells, which is further enhanced with the treatment of GLP-1. These findings confirm that the differentiation of hADSCs to insulin-producing cells is indeed possible and indicate that the differentiated insulin-producing cells can be used as a potential source for transplantation into patients with T1DM.

Expression and gene polymorphisms of interleukin 28B and hepatitis B virus infection in a Chinese Han population

BACKGROUND

Recent genome-wide association studies found that genetic polymorphisms near the IL28B gene is strongly associated with sustained viral response and spontaneous viral clearance in chronically infected hepatitis C patients.

AIMS

We aimed to evaluate the effects of IL28B variations on hepatitis B virus (HBV) infection in a Chinese Han population and to explore the association between IL28B polymorphisms and susceptibility to infection, viral clearance, disease progression, viral load and liver inflammation.

METHODS

We determined three IL28B single gene polymorphisms (rs12979860, rs12980275 and rs8099917) in 203 individuals with chronic HBV infection, 203 individuals with self-limited HBV infection and 203 individuals negative for all HBV seromarkers. Interleukin (IL)28B serum levels were evaluated in all subjects. Additionally, peripheral blood mononuclear cells from 42 chronically HBV-infected individuals were subjected to whole-genome expression studies.

RESULTS

The association among genotype, allele and haplotype frequencies of IL28B with alanine aminotransferase levels and HBV DNA was established. However, no significant differences were observed in genotype or allele frequencies among chronically HBV-infected, self-limited and healthy subjects. The serum IL28B level was lower in patients with chronic HBV infection than in the self-limited HBV-infected or healthy subjects. The serum IL28B level was correlated with the subject's genotype. Gene expression micro-array analysis showed enhanced IL28B expression in patients with low HBV viral load.

CONCLUSIONS

Variability at the IL28B locus is associated with HBV viral load and hepatic inflammation. Genetic variation of IL28B may prevent HBV progression by reducing viral load and liver inflammation, providing a valuable gene therapy tool.

Optimized tandem amiRNA mediates stronger inhibitory effects on hepatitis B virus infection

BACKGROUND AND AIMS

RNA interference (RNAi) has emerged as a potential new approach against hepatitis B virus (HBV) infection but unfortunately it also selects resistant virus mutants. In this study we combined the advantages of artificial micro RNAs (amiRNAs) reported previously with the purpose of constructing a more practical amiRNA with high inhibition effects against HBV.

METHOD

Aiming at conserved sites, we constructed singular-sequence vectors amiRNA-HBV1, amiRNA-HBV2, amiRNA-HBV3 and amiRNA-HBV4. We chose the two sequences of high efficiency, then built the tandem-sequence vector amiRNA-HBV3-HBV4. These vectors were transfected into HepG2.2.15 transiently. The secreted HBV surface antigen (HBsAg) and HBV 'e' antigen (HBeAg) were measured with a chemiluminescent microparticle immunoassay, and intracellular and extracellular HBV DNA was quantified by real-time PCR.

RESULTS

Our results demonstrated that amiRNA-HBV1, amiRNA-HBV2, amiRNA-HBV3, and amiRNA-HBV4 achieved a maximum inhibition of HBV mRNA expression of 29.3%, 14.9%, 61.2%, and 75.6%, respectively, while the tandem amiRNA-HBV3-HBV4 vector led to an inhibition of 87.2%.

CONCLUSION

Taken together, our data suggest that vector-based multiple artificial microRNAs are a promising therapeutic approach for chronic HBV infection.

microRNA-450a targets DNA methyltransferase 3a in hepatocellular carcinoma

microRNAs (miRNAs) have been proven to play key regulatory roles in hepatocarcinogenesis. In the present study, the possible role of microRNA-450a (miR-450a) in hepatocarcinogenesis was investigated. Our study revealed that miR-450a was significantly down-regulated in hepatocellular carcinoma (HCC) tissues compared with that in normal liver (NL) and para-tumorous (PT) tissues, and miR-450a expression in HepG2 cells was significantly lower than that in L02 cells. Both the mRNA and protein levels of the miR-450a potential target gene, DNA methyltransferase 3a (DNMT3a), were obviously higher in HCC compared with levels in the NL and PT tissues. We further identified DNMT3a as the direct target gene for miR-450a, and ectopic miR-450a expression in HepG2 cells caused the down-regulation of DNMT3a and an inhibition of cell proliferation. Taken together, these findings suggest that miR-450a plays an important regulatory role in hepatocarcinogenesis through inhibition of DNMT3a expression, and miR-450a may be a potential target for the treatment of HCC.

Overexpression of Insig-1 protects β cell against glucolipotoxicity via SREBP-1c

BACKGROUND

High glucose induced lipid synthesis leads to β cell glucolipotoxicity. Sterol regulatory element binding protein-1c (SREBP-1c) is reported to be partially involved in this process. Insulin induced gene-1 (Insig-1) is an important upstream regulator of Insig-1-SREBPs cleavage activating protein (SCAP)-SREBP-1c pathway. Insig-1 effectively blocks the transcription of SREBP-1c, preventing the activation of the genes for lipid biosynthesis. In this study, we aimed to investigate whether Insig-1 protects β cells against glucolipotoxicity.

METHODS

An Insig-1 stable cell line was generated by overexpression of Insig-1 in INS-1 cells. The expression of Insig-1 was evaluated by RT-PCR and Western blotting, then, cells were then treated with standard (11.2 mM) or high (25.0 mM) glucose for 0 h, 24 h and 72 h. Cell viability, apoptosis, glucose stimulated insulin secretion (GSIS), lipid metabolism and mRNA expression of insulin secretion relevant genes such as IRS-2, PDX-1, GLUT-2, Insulin and UCP-2 were evaluated.

RESULTS

We found that Insig-1 suppressed the high glucose induced SREBP-1c mRNA and protein expression. Our results also showed that Insig-1 overexpression protected β cells from ER stress-induced apoptosis by regulating the proteins expressed in the IRE1α pathway, such as p-IRE1α, p-JNK, CHOP and BCL-2. In addition, Insig-1 up-regulated the expression of IRS-2, PDX-1, GLUT-2 and Insulin, down-regulated the expression of UCP-2 and improved glucose stimulated insulin secretion (GSIS). Finally, we found that Insig-1 inhibited the lipid accumulation and free fatty acid (FFA) synthesis in a time-dependent manner.

CONCLUSIONS

There results suggest that Insig-1 may play a critical role in protecting β cells against glucolipotoxicity by regulating the expression of SREBP-1c.

A tumor-penetrating peptide modification enhances the antitumor activity of endostatin in vivo

Many antitumor drugs have a limited ability to penetrate more than a few cell diameters from blood vessels into solid tumors, which limits their effectiveness. In this study, we investigated whether the biological activity of endostatin can be enhanced by the addition of an integrin-targeting and permeability-enhancing sequence. The internalization RGD (CRGDKGPDC; iRGD) sequence was added at the carboxyl terminus of endostatin. Modification of endostatin with the iRGD motif showed specific and increased binding to endothelial cells; the increased binding correlated with an improved antiangiogenic property. iRGD-modified endostatin was more effective than human endostatin in inhibiting liver cancer growth in athymic mice. The finding indicates that addition of a vascular targeting and permeability sequence can enhance the biological activity of an antiangiogenic molecule and tumor targeting.

Chronic alcohol consumption induces cardiac remodeling in mice from Th1 or Th2 background

AIMS

The effects of T helper (Th) cells on alcoholic cardiomyopathy have not been extensively investigated. Strain of mice with Th1 or Th2 immunological background were utilized in this study in order to explore the role of Th1/Th2 in chronic alcohol-induced cardiac fibrosis.

METHODS AND RESULTS

C57BL/6 WT or Balb/c mice were treated with alcohol for 90 days. Then cardiac structure and function were analyzed via echocardiography. Spleen CD4+CD25+Foxp3+ Tregs were determined by flow cytometry. The hearts were stained using haematoxylin and eosin (HE) and Masson's trichome. Myocardial ultrastructure was observed by electron microscopy. Expression of T-bet, GATA-3, IL-4 and IFN-gamma were determined by real-time RT-PCR. The heart was dilated significantly in the C57BL/6 WT+alcohol group and Balb/c+alcohol group compared with the controls. CD4+CD25+Foxp3+ Tregs were not statistically different. Masson's trichome staining revealed that fibrosis was more pronounced in the alcohol treated groups than the controls. Fibrosis was more evident in the Balb/c+alcohol group compared to the C57BL/6 WT+alcohol group. Alcohol consumption caused a decrease in the Th1 polarization and an increase in the Th2 response.

CONCLUSIONS

Chronic alcohol consumption induced a Th2 response within the Th1/Th2 balance. Th2 response is one of the underlying mechanism involved in alcohol-induced cardiac fibrosis.

WU polyomavirus infection among children in South China

This study aimed at investigating the prevalence and clinical characteristics of children with respiratory infection by WU polyomavirus (WUPyV) in Southern China. Nasopharyngeal aspirate samples were collected from 771 children with acute respiratory tract infection admitted to hospital and 82 samples from healthy subjects for routine examination at the outpatient service at the Second Affiliated Hospital of Shantou University, Medical College from July 2008 to June 2009. WUPyV was detected by the polymerase chain reaction (PCR) and DNA sequencing. All WUPyV-positive specimens were characterized further for nine viruses causing common respiratory infections, including influenza A and B, respiratory syncytial virus (RSV), parainfluenza virus (PIV) 1 and 3, human metapneumovirus, human bocavirus, adenovirus, and rhinovirus by PCR or real time (RT)-PCR. Fifteen out of 771 specimens from patients with acute respiratory tract infection, but none from healthy subjects, were positive for WUPyV and the positivity rate was 2%. Patients with WUPyV infection were between 2 and 48 months of age, and nine of the patients were male while six female. Four out of 15 patients were co-infected with RSV, one with adenovirus or rhinovirus, respectively. Patients with WUPyV infection displayed predominantly cough, moderate fever, and wheezing, and were diagnosed with pneumonia (n = 8), bronchiolitis (n = 4), upper respiratory tract infections (n = 2) and bronchitis (n = 1). One patient developed encephalitis. Therefore, WUPyV infection can cause acute respiratory tract infection with atypical symptoms, including severe complications, in children.

Effects of Helicobacter pylori eradication on gastroesophageal reflux disease

BACKGROUND AND AIMS

Helicobacter pylori infection appears to be a protective factor for gastroesophageal reflux disease (GERD). However, H. pylori is associated with the subtype of esophageal carcinoma, and long-term proton-pump inhibition usage would cause gastric atrophy in patients with persistent H. pylori infection, which is a precancerous lesion. The relationship between H. pylori infection and GERD is still unclear. We aimed to confirm whether the eradication of H. pylori would worsen or improve symptomatic or endoscopic GERD.

METHODS

A systematic review of the published data was undertaken, and a meta-analysis was performed to determine the effect of H. pylori eradication on the occurrence of symptomatic (heartburn, acid regurgitation) and endoscopically proven erosive (esophagitis) GERD in patients with or without pre-existing GERD.

RESULTS

A total of 11 articles met the inclusion criteria and thus were included in the meta-analysis. There was no significant difference in the frequency of symptomatic or endoscopically proven erosive GERD after the eradication between patients with H. pylori eradicated and those with persistent infection, regardless of follow-up period, location, or the baseline disease.

CONCLUSION

H. pylori eradication does not aggravate the clinical outcomes in terms of short-term and long-term posteradication occurrence of GERD. There is no association between H. pylori eradication and the development of GERD in the patients with different diseases, even those with GERD.

Rosiglitazone protects neuroblastoma cells against advanced glycation end products-induced injury

AIM

To investigate the protective effects of rosiglitazone (RGZ) against the neuronal toxicity induced by advanced glycation end products (AGEs) and the underlying mechanisms.

METHODS

Neuroblastoma cell line SH-SY5Y was used. Cell viability and apoptosis were assessed using MTT assay and flow cytometry, respectively. Superoxide dismutase (SOD) and catalase activities were measured using biochemical methods. Intracellular reactive oxygen species (ROS) were monitored using 2',7'-dichlorodihydro-fluorescein diacetate (DCFH-DA). Secreted β-amyloid(1-42) (Aβ(1-42)) level was assessed by ELISA. The expression of mRNA of Bcl2, Bax, Caspase3, Aβ precursor protein (APP), β-site APP-cleaving enzyme 1 (BACE1), and insulin degrading enzyme (IDE) were measured using quantitative real-time PCR (Q-PCR), and their protein levels were examined using Western blot.

RESULTS

RGZ (0.1-10 μmol/L) significantly increased the cell viability that was reduced by AGEs (1000 μg/mL). RGZ (10 μmol/L) significantly ameliorated AGEs-triggered downregulation of SOD and catalase, and production of ROS. It also reversed Bcl2 downregulation, Bax upregulation and Caspase3 expression caused by AGEs. Moreover, it significantly attenuated AGEs-induced Aβ secretion and APP protein upregulation. RGZ did not affect BACE1 expression, but induced IDE expression, which promoted degradation of Aβ. All the effects were blocked by the specific PPARγ antagonist GW9662 (10 μmol/L).

CONCLUSION

RGZ protects the euroblastoma cells against AGEs-induced injury via its anti-oxidative, anti-apoptotic and anti-inflammatory properties that seems to be mediated by PPARγ activation. The results suggest a beneficial role for RGZ in the treatment of Alzheimer's disease.

Generation and application of anti-ouabain IgY antibodies

Ouabain is a bioactive hapten and is very difficult to be accurately quantified because of the lack of useful reagents. Furthermore, where ouabain is produced in the adrenal glands has not been identified. In this study, ouabain-BSA was generated for immunizing the laying hens to generate ouabain-specific IgY antibodies in chicken eggs. The anti-ouabain IgY antibodies were detected in eggs 1 week after the last immunization and their concentrations increased with time. The highest concentrations of anti-ouabain IgY antibodies reached at 1:10,240 for ELISA 5 weeks after immunization and maintained for 4 weeks in chicken eggs. Following PEG precipitation, an average of 8.5 mg of anti-ouabain IgY antibodies with a purity of 87.6% was achieved from a single egg. Further analysis revealed that the anti-ouabain IgY antibodies had little immunoreactivity to hydrocortisone, dexamethasone, cedilanid, and digoxin, indicating their high specificity, and the purified IgY antibodies effectively detected endogenous ouabain in the cytoplasm of cells predominately in the zona reticularis of rat and human adrenal glands, indicating their high immunoreactivity. Given that IgY has an unique structure and bioactive features, the generated anti-ouabain IgY antibodies may be used as a new reagent for accurately quantifying ouabain in biological studies.

L-carnitine ameliorates cancer cachexia in mice by regulating the expression and activity of carnitine palmityl transferase

Cancer cachexia is characterized by progressive weight loss with the depletion of adipose tissue and skeletal muscle. Impaired fatty acid oxidation mainly resulting from the decrease of carnitine palmitoyltransferase I and II activities in the liver is an important factor that contributes to cancer cachexia . Although recent studies suggest a potential application of L-carnitine in treatment of cancer cachexia, the underlying mechanisms are unknown. In the present study, we aim to assess the effects of L-carnitine on the activity and expression of CPT I and II in the liver of cachectic cancer mice. Our results show that the inoculation of colon-26 adenocarcinoma cells into mice led to cancer cachexia characterized by notable decreases in food intake, gastrocnemius muscle and epididymus fat weight. In addition, the mRNA level and activity of liver carnitine palmitoyltransferase (CPT) I and II, and serum levels of free carnitine and acetylcarnitine were markedly decreased in cachectic mice, accompanied by marked increases in serum levels of tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6). A continuous oral treatment with L-carnitine at 18 mg/kg per day increased dietary uptake, gastrocnemius muscle weight and epididymus fat weight, increased blood glucose and serum albumin levels, and decreased total cholesterol level in cancer cachectic mice, but did not affect tumor growth. These effects of L-carnitine on cancer cachexia mice were accompanied by the upregulation of mRNA level of CPT I and II and increased enzyme activity of CPT I in the liver, as well as the downregulation of serum TNF-α and IL-6 levels. Moreover, free carnitine levels were negatively correlated with serum TNF-α or IL-6 level. These results indicate that L-carnitine ameliorates cancer cachexia by regulating serum TNF-α and IL-6 levels and modulating the expression and activity of CPT in the liver.

Cell budding from pre-invasive tumors: Intrinsic precursor of invasive breast lesions?

Our previous studies showed that in patients with ductal carcinoma in situ (DCIS) of the breast, the tumor cells that overlie focal myoepithelial cell layer disruptions (FMCLDs) are generally arranged as finger-like projections that bud into the stroma. These budding cells have significantly more genetic instability and invasion-related gene expression, and less estrogen receptor (ER) expression, than their epithelial cell counterparts. This study aimed to assess these cells for potential molecular markers that are uniquely associated with cell adhesion and motility. Seventeen ER-positive DCIS cases were screened by immunostaining for ER, and 7 cases which harbored FMCLD lesions were used to examine the expression of the potential markers. Two cases with both DCIS and invasive lesions were selected for comparing the differences in molecular expression between these lesion types. The results showed that expression levels of talin, E-cadherin and focal adhesion kinase (FAK) in tumor cells overlying FMCLDs were higher than those within the corresponding duct. Integrin β1 staining was detected only in a small number of the tumor cells overlying the FMCLDs. Vinculin staining was weak (18%) or not detected (82%), and no expression was found in the tumor cells within the corresponding duct or in the pure isolated DCIS. By contrast, the expression levels of talin, vinculin and integrin β1 in the invasive tumors were distinctly higher than those in DCIS, and the expression of FAK and E-cadherin was lower. Using electron microscopy, we found that the tight junctions between tumor cells overlying the FMCLDs were reduced compared to the adjacent tumor cells in the lumen. These results indicate that the tumor cells overlying FMCLDs are likely to represent the specific precursors of invasive breast lesions. Our findings may also facilitate the identification of specific targets for further molecular profiling, which will more completely characterize this important cell population.

Recombinant canine parvovirus-like particles express foreign epitopes in silkworm pupae

The capsid structural protein VP2 of canine parvovirus (CPV) can self-assemble into highly organized virus-like particles (VLPs) and retain major immunoreactivity. In this study, different recombinant baculoviruses that expressed varying fusion proteins of the CPV VP2 protein with the T cell determinant and/or the linear virus-neutralizing epitope of rabies virus (RV) were generated. Infection with these baculoviruses changed BmN cell morphology and inhibited their proliferation as well as damaged silkworms and pupae. However, infection with these baculoviruses induced high levels of recombinant protein expression in silkworms and pupae. More importantly, these fusion proteins self-assembled VLPs with properties similar to CPV virions and retained their VP2-specific immunoreactivity, but some retained their RV-specific immunoreactivity. Interestingly, only one fusion protein, T-VP2, maintained its haemagglutination activity. These data indicated that these insertions and replacements in the loop 2 of VP2 did not interfere with the formation of VLP, and silkworms and pupae could act as a low-costing bioreactor for the production of heterologous proteins. Therefore, our findings may provide a new framework for the development of subunit vaccines against RV and CPV.

Log-normal censored regression model detecting prognostic factors in gastric cancer: A study of 3018 cases

AIM: To investigate the efficiency of Cox proportional hazard model in detecting prognostic factors for gastric cancer.

METHODS: We used the log-normal regression model to evaluate prognostic factors in gastric cancer and compared it with the Cox model. Three thousand and eighteen gastric cancer patients who received a gastrectomy between 1980 and 2004 were retrospectively evaluated. Clinic-pathological factors were included in a log-normal model as well as Cox model. The akaike information criterion (AIC) was employed to compare the efficiency of both models. Univariate analysis indicated that age at diagnosis, past history, cancer location, distant metastasis status, surgical curative degree, combined other organ resection, Borrmann type, Lauren’s classification, pT stage, total dissected nodes and pN stage were prognostic factors in both log-normal and Cox models.

RESULTS: In the final multivariate model, age at diagnosis, past history, surgical curative degree, Borrmann type, Lauren’s classification, pT stage, and pN stage were significant prognostic factors in both log-normal and Cox models. However, cancer location, distant metastasis status, and histology types were found to be significant prognostic factors in log-normal results alone. According to AIC, the log-normal model performed better than the Cox proportional hazard model (AIC value: 2534.72 vs 1693.56).

CONCLUSION: It is suggested that the log-normal regression model can be a useful statistical model to evaluate prognostic factors instead of the Cox proportional hazard model.

Use of 3D-computed tomography angiography for planning the surgical removal of pineal region meningiomas using Poppen's approach: a report of ten cases and a literature review

BACKGROUND

There are several treatment approaches for pineal region meningiomas, such as Poppen's approach, Krause's approach and combinations of the two approaches. We present our experience with the use of 3D-computed tomography angiography for planning the surgical removal of pineal region meningiomas using a suboccipital transtentorial approach (Poppen's approach) and evaluate the role of Poppen's approach.

METHODS

During the period from January 2005 to June 2010, ten patients presented to us with pineal region meningioma. MRI was routinely used to define the tumor size, position, and its relevant complications while 3D-CTA was applied to define the blood supply of the tumor and the venous complex (VC) shift before operations. Most of the meningiomas had developed at both sides of the tentorial plane and extended laterally with typical characteristics of a pineal region tumor.

RESULTS

All tumors were completely removed surgically without any injury to the VC. Postoperative intracranial infection occurred in one case who recovered after antibiotics were given. Postoperative intraventricular hemorrhage and pneumocephalus were found in one case, but fully recovered after conservative treatment. In the nine cases of concurrent hydrocephalus, this was gradually relieved in eight patients and the single case that became aggravated was successfully treated with ventriculoperitoneal shunt. Moreover, the follow-up MRI examinations did not indicate any recurrence of the meningiomas.

CONCLUSION

We found that the use of Poppen's approach is strongly supported for the successful removal of pineal region meningiomas without serious complications.

Laparoscopic versus open treatment for benign pancreatic insulinomas: an analysis of 89 cases

BACKGROUND

The use of a laparoscopic approach in the treatment of insulinomas is increasing. This retrospective study aimed to evaluate the authors' experience with laparoscopic surgery for benign pancreatic insulinomas and to compare the results for a laparoscopic approach versus an open approach.

METHODS

From January 2000 to December 2009, data were collected retrospectively from 89 patients who underwent resection of pancreatic insulinoma via either laparoscopy (n = 43) or laparotomy (n = 46). Clinical data, tumor features, and intra- and postoperative characteristics were analyzed.

RESULTS

The operation time, blood loss, and complication rate did not differ significantly between the laparoscopic and open approach groups. In the laparoscopic group, the time required to achieve recovery of gastrointestinal function and postoperative oral intake was significantly shorter in the laparotomy group, as was the hospital stay. By the end of the follow-up period, 85 (95.5%) of the 89 patients were symptom free.

CONCLUSIONS

Laparoscopic surgery is a safe procedure for patients with benign insulinomas. The complication rates are comparable with those for laparotomy procedures. Relative to open operations, laparoscopic pancreas operations are associated with a more rapid postoperative recovery.

ENOS-G894T polymorphism is a risk factor for essential hypertension in China

Vascular endothelial cells produce nitric oxide (NO), which contributes to the regulation of blood pressure and regional blood flow. Polymorphisms of the endothelial nitric oxide synthase (eNOS) gene are associated with coronary artery disease; however, associations between polymorphism (G894T) of the eNOS gene and essential hypertension remain unclear. This study was designed to investigate the association between a eNOS-G894T polymorphism and essential hypertension (EH). A total of 190 Chinese EH patients (EH group) and 94 healthy participants (control group) were included in the study. eNOS-G894T was determined using multi-polymerase chain reaction and polymorphisms in eNOS-G894T were genotyped using gene chip technology. Patients carrying eNOS GT + TT genotypes had a higher risk of EH than those carrying the GG genotype (OR = 2.82, 95% CI: 1.05-7.60, P = 0.033). The EH group showed a significantly higher frequency of the T-allele compared with controls (OR = 3.48, 95% CI: 1.34-9.07; P = 0.007). eNOS-894T was found to be significantly associated with EH in the dominant genetic model. Thus, the study demonstrated a significant and independent association between a eNOS-G894T polymorphism and EH in the Chinese patients. The study also showed that eNOS-G894T polymorphism is a risk factor for EH in Chinese patients.

ENOS-G894T polymorphism is a risk factor for essential hypertension in China

Vascular endothelial cells produce nitric oxide (NO), which contributes to the regulation of blood pressure and regional blood flow. Polymorphisms of the endothelial nitric oxide synthase (eNOS) gene are associated with coronary artery disease; however, associations between polymorphism (G894T) of the eNOS gene and essential hypertension remain unclear. This study was designed to investigate the association between a eNOS-G894T polymorphism and essential hypertension (EH). A total of 190 Chinese EH patients (EH group) and 94 healthy participants (control group) were included in the study. eNOS-G894T was determined using multi-polymerase chain reaction and polymorphisms in eNOS-G894T were genotyped using gene chip technology. Patients carrying eNOS GT + TT genotypes had a higher risk of EH than those carrying the GG genotype (OR = 2.82, 95% CI: 1.05-7.60, P = 0.033). The EH group showed a significantly higher frequency of the T-allele compared with controls (OR = 3.48, 95% CI: 1.34-9.07; P = 0.007). eNOS-894T was found to be significantly associated with EH in the dominant genetic model. Thus, the study demonstrated a significant and independent association between a eNOS-G894T polymorphism and EH in the Chinese patients. The study also showed that eNOS-G894T polymorphism is a risk factor for EH in Chinese patients.

HBc binds to the CpG islands of HBV cccDNA and promotes an epigenetic permissive state

HBV covalently closed circular DNA (cccDNA) is the template for the transcription of HBV. HBV core protein (HBc) is a main component of the HBV cccDNA minichromosome. However, the function of HBc in cccDNA is not fully understood. In light of recent findings that HBV cccDNA may be regulated epigenetically, we analyzed the binding of HBc to cccDNA and the impact of HBc on cccDNA epigenetic profile in the liver biopsy samples of 22 patients with chronic Hepatitis B (CHB). We found that HBc binding to HBV cccDNA occurred preferentially at CpG island 2, an important region for the regulation of HBV transcription. Furthermore, the relative abundances of HBc binding to CpG island 2 were positively correlated with the ratios of relaxed circular DNA to cccDNA and the levels of serum HBV DNA in those patients. Interestingly, the relative abundances of HBc binding to CpG island 2 were associated with the binding of CREB binding protein (CBP) and with hypomethylation in CpG island 2 of HBV cccDNA minichromosomes. However, relatively higher amounts of HBc binding to CpG island 2 of cccDNA were accompanied by lower amounts of HDAC1 binding. Multivariate analysis revealed that the abundances of HBc binding to CpG island 2 of cccDNA and positive HBeAg were independent factors associated with the replication of HBV (p = 0.001 for both). Apparently, HBc is a positive regulator of HBV transcription and replication, maintaining the permissive epigenetic state in the critical region of the HBV cccDNA minichromosomes.

More than adequate iodine intake may increase subclinical hypothyroidism and autoimmune thyroiditis: a cross-sectional study based on two Chinese communities with different iodine intake levels

OBJECTIVE

With the introduction of iodized salt worldwide, more and more people are exposed to more than adequate iodine intake levels with median urinary iodine excretion (MUI 200-300 μg/l) or excessive iodine intake levels (MUI >300 μg/l). The objective of this study was to explore the associations between more than adequate iodine intake levels and the development of thyroid diseases (e.g. thyroid dysfunction, thyroid autoimmunity, and thyroid structure) in two Chinese populations.

DESIGN

A population-based cross-sectional study was conducted in two areas in which people are exposed to different levels of iodine intake (Rongxing, MUI 261 μg/l; Chengshan, MUI 145 μg/l). A total of 3813 individuals were recruited by random sampling. Thyroid hormones, thyroid autoantibodies in serum, and iodine levels in urine were measured. B-mode ultrasonography of the thyroid was also performed for each participant.

RESULTS

The prevalence of subclinical hypothyroidism was significantly higher for subjects who live in Rongxing than those who live in Chengshan (5.03 vs 1.99%, P<0.001). The prevalence of positive anti-thyroid peroxidase antibody (TPOAb) and positive anti-thyroglobulin antibody (TgAb) was significantly higher for subjects in Rongxing than those in Chengshan (TPOAb: 10.64 vs 8.4%, P=0.02; TgAb: 10.27 vs 7.93%, P=0.01). The increase in thyroid antibodies was most pronounced in the high concentrations of TPOAb (TPOAb: ≥500 IU/ml) and low concentrations of TgAb (TgAb: 40-99 IU/ml) in Rongxing.

CONCLUSIONS

More than adequate iodine intake could be a public health concern in terms of thyroid function and thyroid autoimmunity in the Chinese populations.

Human papillomavirus infection in nasal polyps in a Chinese population

In order to determine the prevalence and genotype distribution of human papillomavirus (HPV) infection in patients with nasal polyps, a total of 204 patients with nasal polyps and 36 healthy controls were recruited for this study. Genomic DNA was extracted from paraffin-embedded tissue sections. HPV DNA genotyping was achieved by a flow-through hybridization and gene-chip method. HPV-positive infection was identified in 82 of 204 (40.2 %) patients, while HPV DNA was not found in healthy controls (P<0.05). Genotyping analysis showed that low-risk HPV genotype 11 was the most prevalent type of HPV in nasal polyps (45.28 %). Both single and multiple HPV genotype infections were found in these HPV-positive cases, although most (74.39 %) were infected with a single genotype. In addition, there was no correlation between HPV infection or HPV subtypes and the clinicopathological characteristics of patients, such as age, gender, number of surgery and disease course. The data from our study clearly demonstrated that HPV infection was associated with nasal polyps. Both high-risk HPV and low-risk HPV (LR-HPV) genotypes were identified in nasal polyp tissues, and LR-HPV-11 was the most prevalent type. Future research will explore the association of HPV infection with the development and progression of nasal polyps.