Telomerase antisense inhibition for the proliferation of endometrial cancer in vitro and in vivo

The objective of this study was to investigate the antitumor effect of antisense telomerase oligodeoxynucleotides to endometrial cancer cells in vitro and in vivo. Antisense oligodeoxynucleotides (ODNs) against the human telomerase transcripatse (hTERT) synthesized to serve as telomerase inhibitors. Reverse transcription–polymerase chain reaction and 3-[4,5-dimethylthiazol-2yl]-2,5-diphenyltetrazolium bromide (MTT) assay were used to test the expression of hTERT messengerRNA (mRNA) and inhibition of cell proliferation in vitro. In vivo, antitumor effects of ODNs or combined with cisplatin were evaluated in endometrial cancer xenograft. Telomerase activity was tested by telomeric repeat amplification protocol. Antisense ODNs could inhibit proliferation of human endometrial cancer cells (HEC-1-A) in vitro, and downregulate the expression hTRET mRNA in a dose- and period-dependent manner. The tumor growth inhibitory rate of low- and high-dose ODNs were 34.20% and 89.21%, and combined group was 75.30%. Telomerase activity was downregulated to 87.32% compared to the control in the ODNs-treated xenograft tumors. Antisense oligonucleotides of hTERT effectively inhibit the growth of endometrial cancer cell line. Telomerase inhibitor might be a new strategy for chemotherapy or chemoprevention in endometrial cancer.

CYP19A1 genetic polymorphisms may be associated with obesity-related phenotypes in Chinese women

OBJECTIVE

To examine the relationship between genetic polymorphisms of the CYP19A1 gene and obesity-related phenotypes, body mass index (BMI) and waist-to-hip ratio (WHR).

SUBJECTS

In total, 1241 Chinese women, who were recruited as community controls for a population-based case-control study of breast cancer.

METHODS

Nineteen haplotype tagging single nucleotide polymorphisms (htSNPs) in four haplotype blocks were genotyped.

RESULTS

Significant associations were observed for WHR at three SNPs that are located in haplotype block 1, including rs2445765, rs1004984 and rs1902584 (P=0.05, 0.04 and 0.01, respectively). Women, particularly premenopausal women, who carried the minor allele at any of these SNPs, had higher WHR than those without it. Of these three SNPs, the strongest association was observed at rs1902584, which is the closest to Promoter I.4, the major promoter for adipose tissue. Haplotype analyses indicated an association between the haplotype TCCAT in block 1 and WHR with a P-value of 0.02.

CONCLUSION

These results suggested that CYP19A1 genetic polymorphisms may be associated with the risk of obesity among Chinese women, especially among premenopausal women. The CYP19A1 protein (aromatase) plays a critical role in estrogen biosynthesis and thus affects body fat distribution and regulation.

Dehalogenation of halogenated fumigants by polysulfide salts

Halogenated fumigants are among the most heavily used pesticides in agriculture. Because of their high mobility and toxicological characteristics, the contamination of air or groundwater by these compounds has been a great environmental concern. In this study, we investigated dehalogenation of several halogenated fumigants by polysulfides. The reaction of polysulfides and methyl iodide (MeI), 1,3-dichloropropene (1,3-D), and chloropicrin (CP) was very rapid. When the initial fumigant and polysulfide concentrations were both 0.2 mM, the observed 50% disappearance time values (DT50) of MeI, cis-1,3-D, and trans-1,3-D were 27.2, 29.6, and 102 h, respectively. When the initial polysulfide concentration was 1.0 mM, the corresponding DT50 values were only 2.2, 1.6, and 3.8 h. Under similar conditions, the reaction with CP was even more rapid than with the other fumigants. In 0.2 mM polysulfide solution, more than 90% of the spiked CP disappeared in 1 h after the initiation of the reaction. The reaction between fumigants and polysulfides also progressed at enhanced rates when the polysulfide solution was initially purged with nitrogen. Analysis of reaction kinetics and initial products suggests that the reaction is SN2 nucleophilic substitution for MeI and 1,3-D but likely reductive dehalogenation for CP. Given the high reactivity of polysulfide salts toward halogenated fumigants, this reaction may be used as a pollution mitigation strategy, such as for disposal of fumigant wastes, treatment of fumigant-containing wastewater, and cleanup of fumigant residues in environmental media.

Isolation and characterization of a novel Burkholderia cepacia with strong antifungal activity against Rhizoctonia solani

Strain CF-66 with strong antifungal activity against Rhizoctonia solani was isolated from compost samples. It is clearly demonstrated that strain CF-66 is belonging to Burkholderia cepacia complex by the morphological and biochemical tests and 16S rDNA sequence. The B. cepacia complex consists of a group of bacteria currently organized into nine genomovars, among them genomovar II and genomovar III, contain the highly epidemic strains. However, it was known that strain CF-66 is not a member of genomovar II or III of the B. cepacia complex by species-specific polymerase chain reaction assay. In this study, the antifungal compound CF66I produced by strain CF-66 was purified and characterized. Based on the nuclear magnetic resonance, GC-MS spectral and infrared spectral data, CF66I was confirmed to have amide bonds, alpha-methyl fatty acid, bromine, and some structural units such as CH(2)CH(2)O. CF66I is stable to high temperature, proteolytic enzymes, and organic solvents. CF66I inhibit the growth of a variety of plant pathogenic fungi and pathogenic yeast, whereas bacterial cells are unaffected. CF66I mainly reduced hyphal extension rates in a dose-dependent manner and induced severe change in cell morphology that resulted in swelled and formed very short hyphae with multiple branches.

Plasminogen Activator Inhibitor-1 Promoter Polymorphism is Not Associated With the Aggressiveness of Disease in Prostate Cancer

AIMS

PAI-1 (plasminogen activator inhibitors-1) regulates plasminogen activation, and is related to tumour development. This study aims to test whether the promoter polymorphism in the PAI-1 gene is related to the aggressiveness of disease in prostate cancer.

MATERIALS AND METHODS

In the present study, Taqman SNP genotyping assay was used to detect PAI-1 4G/5G polymorphism in DNA from paraffin-embedded tissues of 98 Caucasian patients with prostate cancer.

RESULTS

The distribution of the genotypes is in Hardy-Weinberg equilibrium. The genotype had no statistically significant relationship with other prognostic factors. Similar risks for recurrence were seen in individuals with the 4G/4G and 4G/5G genotypes compared to those with 5G/5G genotype (odds ratio [OR] 2.65, 95% CI: 0.41-16.94, P = 0.30; OR = 2.19, 95% CI: 0.38-12.49, P = 0.38).

CONCLUSION

We concluded that PAI-1 promoter polymorphism is not associated with the aggressiveness of disease in prostate cancer.

Mutation Glu82Lys in lamin A/C gene is associated with cardiomyopathy and conduction defect

Dilated cardiomyopathy is a form of heart muscle disease characterized by impaired systolic function and ventricular dilation. The mutations in lamin A/C gene have been linked to dilated cardiomyopathy. We screened genetic mutations in a large Chinese family of 50 members including members with dilated cardiomyopathy and found a Glu82Lys substitution mutation in the rod domain of the lamin A/C protein in eight family members, three of them have been diagnosed as dilated cardiomyopathy, one presented with heart dilation. The pathogenic mechanism of lamin A/C gene defect is poorly understood. Glu82Lys mutated lamin A/C and wild type protein was transfected into HEK293 cells. The mutated protein was not properly localized at the inner nuclear membrane and the emerin protein, which interacts with lamin A/C, was also aberrantly distributed. The nuclear membrane structure was disrupted and heterochromatin was aggregated aberrantly in the nucleus of the HEK293 cells stably transfected with mutated lamin A/C gene as determined by transmission electron microscopy.

Discordant genetic changes in ovarian and endometrial endometrioid carcinomas: a potential pitfall in molecular diagnosis

Endometrioid carcinoma simultaneously involving ovaries as well as the uterine corpus may present a diagnostic dilemma because of the difficulty in determining whether the lesions are separate primary tumors or metastases. It has been reported that the detection of clonality using microsatellite markers may be useful in solving this dilemma. To determine the usefulness of this technique, we compared the genetic alterations in microsatellite markers present in matched pairs of ovarian tumors from 12 patients. The study includes four ovarian cancer FIGO stage I and eight stage III/IV patients, and four patients also with independent endometrial carcinoma of the uterus. DNA from paraffin-embedded tissue was extracted and amplified using a multiplex polymerase chain reaction, after which the status of microsatellite instability and loss of heterozygosity in four microsatellite loci (BAT25, BAT26, D17S250, and D5S346) were determined. In the four patients with stage I ovarian cancer, four microsatellite markers were identical in one patient and three were identical in the remaining three patients. In high-stage patients, three markers were identical in at least 4/8 cases. In three of four patients with uterine involvement, three of the four markers were identical in the uterine tumor and one of the corresponding ovarian tumors. These results suggest that genetic discordance does not indicate independent origin or metastasis of the tumor but instead a progression of genetic changes at separate sites probably due to the marked genetic instability existing in these tumors. Because of these discordant genetic changes, great caution should be taken when distinguishing between primary and metastatic tumors on the basis of microsatellite markers.

Hydration and dynamic fatigue of dentin

An experimental investigation on the dynamic fatigue response of dentin was conducted to examine the influence of stress rate on the strength and energy to fracture. Rectangular beams were prepared from the coronal dentin of bovine maxillary molars and subjected to four-point flexure to failure. The dentin beams were examined in the fully hydrated and dehydrated condition at stress rates (sigma) ranging from 0.01 to 100 MPa/s. Results for the hydrated dentin showed that the flexure strength, energy to fracture, and flexure modulus all increased with increasing stress rate; the flexure strength increased from 100 MPa ((sigma) = 0.01 MPa/s) to 250 MPa ((sigma) = 100 MPa/s). In contrast, the elastic modulus and strength of the dehydrated dentin decreased with increasing stress rate; the flexural strength of the dehydrated dentin deceased from 170 MPa ((sigma) = 0.01 MPa/s) to 100 MPa ((sigma) = 100 MPa/s). While the hydrated dentin behaved more like a brittle material at low stress rates, the strain to fracture was found to be nearly independent of (sigma). According to the experimental results, restorative conditions that cause development of static stresses within the tooth could promote a decrease in the damage tolerance of dentin.

Blood harmane concentrations and dietary protein consumption in essential tremor

BACKGROUND

Beta-carboline alkaloids (e.g., harmane) are highly tremorogenic chemicals. Animal protein (meat) is the major dietary source of these alkaloids. The authors previously demonstrated that blood harmane concentrations were elevated in patients with essential tremor (ET) vs controls. Whether this difference is due to greater animal protein consumption by patients or their failure to metabolize harmane is unknown.

OBJECTIVE

The aim of this study was to determine whether patients with ET and controls differ with regard to 1) daily animal protein consumption and 2) the correlation between animal protein consumption and blood harmane concentration.

METHODS

Data on current diet were collected with a semiquantitative food frequency questionnaire and daily calories and consumption of animal protein and other food types was calculated. Blood harmane concentrations were log-transformed (logHA).

RESULTS

The mean logHA was higher in 106 patients than 161 controls (0.61 +/- 0.67 vs 0.43 +/- 0.72 g(-10)/mL, p = 0.035). Patients and controls consumed similar amounts of animal protein (50.2 +/- 19.6 vs 49.4 +/- 19.1 g/day, p = 0.74) and other food types (animal fat, carbohydrates, vegetable fat) and had similar caloric intakes. In controls, logHA was correlated with daily consumption of animal protein (r = 0.24, p = 0.003); in patients, there was no such correlation (r = -0.003, p = 0.98).

CONCLUSIONS

The similarity between patients and controls in daily animal protein consumption and the absence of the normal correlation between daily animal protein consumption and logHA in patients suggests that another factor (e.g., a metabolic defect) may be increasing blood harmane concentration in patients.

An Activated GOPS-poly-L-Lysine- Coated Glass Surface for the Immobilization of 60mer Oligonucleotides

To explore a method for enhancing the immobilization and hybridization efficiency of oligonucleotides on DNA microarrays, conventional protocols of poly‐L‐lysine coating were modified by means of surface chemistry, namely, the slides were prepared by the covalently coupling of poly‐L‐lysine to a glycidoxy‐modified glass surface. The modified slides were then used to print microarrays for the detection of the SARS coronavirus by means of 60mer oligonucleotide probes. The characteristics of the modified slides concerning immobilization efficiency, hybridization dynamics, and probe stripping cycles were determined. The improved surface exhibited high immobilization efficiency, a good quality uniformity, and satisfactory hybridization dynamics. The spotting concentration of 10 μmol/L can meet the requirements of detection; the spots were approximately 170 nm in diameter; the mean fluorescence intensity of the SARS spots were between 3.2 × 10⁴ and 5.0 × 10⁴ after hybridization. Furthermore, the microarrays prepared by this method demonstrated more resistance to consecutive probe stripping cycles. The activated GOPS‐PLL slide could undergo hybridization stripping cycles for at least three cycles, and the highest loss in fluorescence intensity was found to be only 11.9 % after the third hybridization. The modified slides using the above‐mentioned method were superior to those slides treated with conventional approaches, which theoretically agrees with the fact that modification by surface chemistry attaches the DNA covalently firmly to the slides. This protocol may have great promise in the future for application in large‐scale manufacture.

One of the key steps in oligonucleotide microarray fabrication is the immobilization of oligonucleotides on a modified glass slide surface. Conventional protocols of poly‐L‐lysine coating were modified by means of surface chemistry in a way similar to the immobilization of 60mer oligonucleotides by deposition technology. The slides prepared by covalently coupling of poly‐L‐lysine to a glycidoxy‐modified glass surface were used to print microarrays for the detection of the SARS coronavirus.

A case-control study in Shanghai of fruit and vegetable intake and endometrial cancer

In a population-based case–control study of 832 incident endometrial cancer cases and 846 frequency-matched controls among Chinese women in Shanghai, using a validated food-frequency questionnaire, dietary habits were estimated by in-person interviews. Total vegetable consumption was inversely associated with endometrial cancer risk (highest quartile vs lowest: OR=0.69, 95% CI 0.50–0.96). The risk was reduced with increasing intake of dark green/dark yellow vegetables (trend test, P=0.02), fresh legumes (trend test, P<0.01), and allium vegetables (trend test, P=0.04). Fruit consumption was unrelated to risk. These results suggest that high consumption of certain vegetables may reduce the risk of endometrial cancer.

Variation in nutrient intakes among women in Shanghai, China

BACKGROUND

In 1997, we launched a large population-based cohort study, the Shanghai Women Health Study (SWHS), to investigate diet in relation to cancer risk among 74 943 Chinese women. Simultaneously, a dietary calibration study was conducted among 200 SWHS participants with biweekly 24-h dietary recall (24HDR) over a 1-y period in order to evaluate the validity and reliability of the SWHS food frequency questionnaire (FFQ).

OBJECTIVE

The objectives of the current study were to evaluate the nature and magnitude of variances for intake of 26 nutrients among SWHS participants, and to estimate the number of 24HDR needed for estimate intake of the 26 nutrients examined in the study population.

DESIGN

In all, 1-y biweekly 24HDR collected from 200 healthy, free-living women aged between 40 and 70 y, who participated in the SWHS dietary calibration study, was analyzed by mixed effects model and ratios of within-individual and between-individual dietary intake variances (sigma(w)(2)/sigma(b)(2)) were estimated.

RESULTS

In agreement with reports from studies conducted in the US, we found that within-individual variances were larger than between-individual variances in dietary intake of most nutrients. The sum of all other variation (eg, weekday and weekend, seasonal, interviewer) accounted for less than 5% of total variation. Ratios of within- to between-individual variances (for log transformed data) ranged from 1.05 (carbohydrate) to 2.79 (fat) for macronutrient intake, 1.74 (niacin) to 8.48 (delta-tocopherol) for vitamin intake, and 1.35 (phosphorus) to 5.59 (sodium) for mineral intake.

CONCLUSIONS

The results of this study suggest that within- and between-individual differences in nutrient intake are the major sources of variation in this population of adult Chinese women. Cultural practices as well as seasonal supply and consumption patterns of vegetable intake are likely the major contributors to the variation. Implications of these results are discussed.

QSAR modeling of datasets with enantioselective compounds using chirality sensitive molecular descriptors

Shape descriptors used in 3D QSAR studies naturally take into account chirality; however, for flexible and structurally diverse molecules such studies require extensive conformational searching and alignment. QSAR modeling studies of two datasets of fragrance compounds with complex stereochemistry using simple alignment-free chirality sensitive descriptors developed in our laboratories are presented. In the first investigation, 44 alpha-campholenic derivatives with sandalwood odor were represented as derivatives of several common structural templates with substituents numbered according to their relative spatial positions in the molecules. Both molecular and substituent descriptors were used as independent variables in MLR calculations, and the best model was characterized by the training set q2 of 0.79 and external test set r2 of 0.95. In the second study, several types of chirality descriptors were employed in combinatorial QSAR modeling of 98 ambergris fragrance compounds. Among 28 possible combinations of seven types of descriptors and four statistical modeling techniques, k nearest neighbor classification with CoMFA descriptors was initially found to generate the best models with the internal and external accuracies of 76 and 89%, respectively. The same dataset was then studied using novel atom pair chirality descriptors (cAP). The cAP are based on a modified definition of the atomic chirality, in which the seniority of the substituents is defined by their relative partial charge values: higher values correspond to higher seniorities. The resulting models were found to have higher predictive power than those developed with CoMFA descriptors; the best model was characterized by the internal and external accuracies of 82 and 94%, respectively. The success of modeling studies using simple alignment free chirality descriptors discussed in this paper suggests that they should be applied broadly to QSAR studies of many datasets when compound stereochemistry plays an important role in defining their activity.

Stress ratio contributes to fatigue crack growth in dentin

An experimental study of fatigue crack growth in dentin was conducted, and the influence of stress ratio (R) on the crack growth rate and mechanisms of cyclic extension were examined. Double Cantilever Beam (DCB) fatigue specimens were sectioned from bovine molars and then subjected to high cycle fatigue loading (10(5) < N < 10(6)) under hydrated conditions. The evaluation consisted of Mode I loads with stress ratios that ranged from -0.5 to 0.5. The fatigue crack growth rates were measured and used to estimate the crack growth exponent (m) and coefficient (C) according to the Paris Law model. The fatigue crack growth rates for steady-state extension (Region II) ranged from 1E-7 to 1E-4 mm/cycle. It was found that the rate of cyclic extension increased significantly with increasing R, and that the highest average crack growth rate occurred at a stress ratio of 0.5. However, the crack growth exponent decreased with increasing R from an average of 4.6 (R = 0.10) to 2.7 (R = 0.50). The stress intensity threshold for crack growth decreased with increasing R as well. Results from this study suggest that an increase in the cyclic stress ratio facilitates fatigue crack growth in dentin and increases the rate of cyclic extension, both of which are critical concerns in minimizing tooth fractures and maintaining lifelong oral health.