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1.  Mst1/2 signalling to Yap: gatekeeper for liver size and tumour development 
British Journal of Cancer  2010;104(1):24-32.
The mechanisms controlling mammalian organ size have long been a source of fascination for biologists. These controls are needed to both ensure the integrity of the body plan and to restrict inappropriate proliferation that could lead to cancer. Regulation of liver size is of particular interest inasmuch as this organ maintains the capacity for regeneration throughout life, and is able to regain precisely its original mass after partial surgical resection. Recent studies using genetically engineered mouse strains have shed new light on this problem; the Hippo signalling pathway, first elucidated as a regulator of organ size in Drosophila, has been identified as dominant determinant of liver growth. Defects in this pathway in mouse liver lead to sustained liver overgrowth and the eventual development of both major types of liver cancer, hepatocellular carcinoma and cholangiocarcinoma. In this review, we discuss the role of Hippo signalling in liver biology and the contribution of this pathway to liver cancer in humans.
PMCID: PMC3039822  PMID: 21102585
liver cancer; hepatocellular carcinoma; cholangiocarcinoma; oval cells; Hippo; Rassf polypeptides; tumour suppressor pathway
2.  Association of genetic variation in FTO with risk of obesity and type 2 diabetes with data from 96,551 East and South Asians 
Diabetologia  2011;55(4):981-995.
FTO harbours the strongest known obesity-susceptibility locus in Europeans. While there is growing evidence for a role for FTO in obesity risk in Asians, its association with type 2 diabetes, independently of BMI, remains inconsistent. To test whether there is an association of the FTO locus with obesity and type 2 diabetes, we conducted a meta-analysis of 32 populations including 96,551 East and South Asians.
All studies published on the association between FTO-rs9939609 (or proxy [r2 > 0.98]) and BMI, obesity or type 2 diabetes in East or South Asians were invited. Each study group analysed their data according to a standardised analysis plan. Association with type 2 diabetes was also adjusted for BMI. Random-effects meta-analyses were performed to pool all effect sizes.
The FTO-rs9939609 minor allele increased risk of obesity by 1.25-fold/allele (p = 9.0 × 10−19), overweight by 1.13-fold/allele (p = 1.0 × 10−11) and type 2 diabetes by 1.15-fold/allele (p = 5.5 × 10−8). The association with type 2 diabetes was attenuated after adjustment for BMI (OR 1.10-fold/allele, p = 6.6 × 10−5). The FTO-rs9939609 minor allele increased BMI by 0.26 kg/m2 per allele (p = 2.8 × 10−17), WHR by 0.003/allele (p = 1.2 × 10−6), and body fat percentage by 0.31%/allele (p = 0.0005). Associations were similar using dominant models. While the minor allele is less common in East Asians (12–20%) than South Asians (30–33%), the effect of FTO variation on obesity-related traits and type 2 diabetes was similar in the two populations.
FTO is associated with increased risk of obesity and type 2 diabetes, with effect sizes similar in East and South Asians and similar to those observed in Europeans. Furthermore, FTO is also associated with type 2 diabetes independently of BMI.
Electronic supplementary material
The online version of this article (doi:10.1007/s00125-011-2370-7) contains peer-reviewed but unedited supplementary material, which is available to authorised users.
PMCID: PMC3296006  PMID: 22109280
Asians; FTO; Meta-analysis; Obesity; Type 2 diabetes
3.  Adenovirus-Based Vaccines: Comparison of Vectors from Three Species of Adenoviridae ▿  
Journal of Virology  2010;84(20):10522-10532.
In order to better understand the broad applicability of adenovirus (Ad) as a vector for human vaccine studies, we compared four adenovirus (Ad) vectors from families C (Ad human serotype 5 [HAdV-5; here referred to as AdHu5]), D (HAdV-26; here referred to as AdHu26), and E (simian serotypes SAdV-23 and SAdV-24; here referred to as chimpanzee serotypes 6 and 7 [AdC6 and AdC7, respectively]) of the Adenoviridae. Seroprevalence rates and titers of neutralizing antibodies to the two human-origin Ads were found to be higher than those reported previously, especially in countries of sub-Saharan Africa. Conversely, prevalence rates and titers to AdC6 and AdC7 were markedly lower. Healthy human adults from the United States had readily detectable circulating T cells recognizing Ad viruses, the levels of which in some individuals were unexpectedly high in response to AdHu26. The magnitude of T-cell responses to AdHu5 correlated with those to AdHu26, suggesting T-cell recognition of conserved epitopes. In mice, all of the different Ad vectors induced CD8+ T-cell responses that were comparable in their magnitudes and cytokine production profiles. Prime-boost regimens comparing different combinations of Ad vectors failed to indicate that the sequential use of Ad vectors from distinct families resulted in higher immune responses than the use of serologically distinct Ad vectors from the same family. Moreover, the transgene product-specific antibody responses induced by the AdHu26 and AdC vectors were markedly lower than those induced by the AdHu5 vector. AdHu26 vectors and, to a lesser extent, AdC vectors induced more potent Ad-neutralizing antibody responses. These results suggest that the potential of AdHu26 as a vaccine vector may suffer from limitations similar to those found for vectors based on other prevalent human Ads.
PMCID: PMC2950567  PMID: 20686035
4.  Muscle‐specific creatine kinase gene polymorphism and running economy responses to an 18‐week 5000‐m training programme 
Zhou, D Q | Hu, Y | Liu, G | Gong, L | Xi, Y | Wen, L
British Journal of Sports Medicine  2006;40(12):988-991.
To investigate the association between muscle‐specific creatine kinase (CKMM) gene polymorphism and the effects of endurance training on running economy.
102 biologically unrelated male volunteers from northern China performed a 5000‐m running programme, with an intensity of 95–105% ventilatory threshold. The protocol was undertaken three times per week and lasted for 18 weeks. Running economy indexes were determined by making the participants run on a treadmill before and after the protocol, and the A/G polymorphism in the 3′ untranslated region of CKMM was detected by polymerase chain reaction‐restricted fragment length polymorphism (NcoI restriction enzyme).
Three expected genotypes for CKMM‐NcoI (AA, AG and GG) were observed in the participants. After training, all running economy indexes declined markedly. Change in steady‐state consumption of oxygen, change in steady‐state consumption of oxygen by mean body weight, change in steady‐state consumption of oxygen by mean lean body weight and change in ventilatory volume in AG groups were larger than those in AA and GG groups.
The findings indicate that the CKMM gene polymorphism may contribute to individual running economy responses to endurance training.
PMCID: PMC2577470  PMID: 17000714
5.  Variants in KCNQ1 are associated with susceptibility to type 2 diabetes in the population of mainland China 
Diabetologia  2009;52(7):1315-1321.
Two recent genome-wide association studies have identified several novel type 2 diabetes susceptibility variants in intron 15 of the KCNQ1 gene. We aimed to evaluate the effects of the variants in KCNQ1 on type 2 diabetes and metabolic traits in the population of mainland China.
Three candidate single nucleotide polymorphisms were genotyped in 1,912 individuals with type 2 diabetes and 2,041 normal controls using the ligase detection reaction method.
We confirmed the association of KCNQ1 with type 2 diabetes in the population of mainland China. Allele frequency ORs of the three single nucleotide polymorphisms (SNPs) were: rs2237892 (OR 1.19, 95% CI 1.08–1.31, p = 3.0 × 10−4); rs2237895 (OR 1.20, 95% CI 1.09–1.32, p = 1.9 × 10−4); and rs2237897 (OR 1.24, 95% CI 1.13–1.36, p = 3.9 × 10−5). We also found a significant difference in the distribution of the global haplotypes between the type 2 diabetes group and the normal control group (p = 2.6 × 10−5). In addition, in the control group SNP rs2237892 was marginally associated with increasing fasting plasma glucose and SNPs rs2237892 and rs2237897 were associated with HbA1c. Furthermore, for all three variants, homozygous carriers of the diabetes-associated allele had significantly decreased BMI and waist circumferences.
Our investigation confirmed the effects of KCNQ1 variants on type 2 diabetes risk in the Chinese population.
Electronic supplementary material
The online version of this article (doi:10.1007/s00125-009-1375-y) contains supplementary material, which is available to authorised users.
PMCID: PMC2688614  PMID: 19448982
Association; KCNQ1; Mainland Chinese population; Type 2 diabetes
6.  SNP A79G in the second exon of the myoglobin gene in elite long distance runners 
Wu, J | Hu, Y | Liu, G | Zhou, D
British Journal of Sports Medicine  2005;39(10):781-782.
PMCID: PMC1725046  PMID: 16183777
7.  The relationship of fluorosis and brick tea drinking in Chinese Tibetans. 
Cao, J | Bai, X | Zhao, Y | Liu, J | Zhou, D | Fang, S | Jia, M | Wu, J
Environmental Health Perspectives  1996;104(12):1340-1343.
Brick tea-drinking fluorosis is an unusual environmental problem. As a result of an investigation of tea-drinking habits, total fluoride intakes, dental fluorosis, and skeletal fluorosis, this disease has been found in the Sichuan Province of China in Tibetans with a long history of drinking brick tea. The dental fluorosis investigation of 375 Tibetan children (213 males, 162 females) and 161 Han children (86 males, 75 females), 8-15 years of age, was carried out in Daofu County, Sichuan Province. According to the standard of the Chinese Health Ministry, a skeletal fluorosis survey of 658 Tibetans (264 males, 394 females) and 41 Hans (20 males, 11 females), all over 16 years old, was performed. The total fluoride intake and fluorosis were determined from a question--calculation method in all participants. The morbidities of dental fluorosis in Tibetan and Han children are 51.2% and 11.05%, respectively, and the indexes of dental fluorosis are 1.33 and 0.17 (chi 2 = 75.7, p < 0.01) respectively. The morbidity of skeletal fluorosis is 32.83% for Tibetan children and zero for the Han children. The fluoride intakes of Tibetan children and adults were 5.49 mg/person/day and 10.43 mg/person/day, respectively, in this area. Of total everyday fluoride intake, 94.2% by children and 94.4% by adults was from brick tea and zanba (r = 0.99).
PMCID: PMC1469557  PMID: 9118877
8.  Normalization of diabetes in spontaneously diabetic cynomologus monkeys by xenografts of microencapsulated porcine islets without immunosuppression. 
Journal of Clinical Investigation  1996;98(6):1417-1422.
Porcine pancreatic islets were microencapsulated in alginate-polylysine-alginate capsules and transplanted intraperitoneally into nine spontaneously diabetic monkeys. After one, two, or three transplants of 3-7 x 10(4) islets per recipient, seven of the monkeys became insulin independent for periods ranging from 120 to 804 d with fasting blood glucose levels in the normoglycemic range. Glucose clearance rates in the transplant recipients were significantly higher than before the graft administration and the insulin secretion during glucose tolerance tests was significantly higher compared with pretransplant tests. Porcine C-peptide was detected in all transplant recipients throughout their period of normoglycemia while none was found before the graft administration. Hemoglobin A1C levels dropped significantly within 2 mo after transplantation. While ketones were detected in the urine of all recipients before the graft administration, all experimental animals became ketone free 2 wk after transplantation. Capsules recovered from two recipients 3 mo after the restoration of normoglycemia were found physically intact with enclosed islets clearly visible. The capsules were free of cellular overgrowth. Examination of internal organs of two of the animals involved in our transplantation studies for the duration of 2 yr revealed no untoward effect of the extended presence of the microcapsules.
PMCID: PMC507568  PMID: 8823307
9.  Microheterogeneity of Neisseria lipooligosaccharide: analysis of a UDP-glucose 4-epimerase mutant of Neisseria meningitidis NMB. 
Infection and Immunity  1995;63(7):2508-2515.
Neisseria meningitidis is the etiologic agent of epidemic bacterial meningitis. Lipooligosaccharide (LOS) is a principal virulence factor associated with the organism, and sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis of LOS has demonstrated that there is considerable microheterogeneity in the molecule. To begin our understanding of the nature of this heterogeneity, we identified a Tn916-generated LOS mutant of N. meningitidis NMB (serotype L3, monoclonal antibodies 3F11+, 6B4+, and 4C4-) that was designated NMB-SS3 (monoclonal antibodies 3F11-, 6B4-, and 4C4+). The transposon insertion was localized to the amino terminus of the functional copy of the UDP-Glc 4-epimerase gene (galE). UDP-Glc 4-epimerase (EC activity was present in N. meningitidis NMB but not in NMB-SS3, indicating that the Tn916 insertion had abolished this activity. Mass spectrometric analysis of the LOS from strain NMB revealed multiple species of LOS, which is consistent with extensive microheterogeneity. While the most predominant structure was consistent with a terminal lacto-N-neotetrose structure found in other strains of N. meningitidis, Gal beta 1-->4GlcNAc beta 1-->3Gal beta 1-->4Glc-->(GlcNAc)-->Hep2PEA-->KDO2 (where Hep is heptose, PEA is phosphoethanolamine, and KDO is 2-keto-3-deoxymannooctulosonic acid), structures containing repetitive hexoses which are not precursors of this structure were also identified. Compositional analysis of LOS from strain NMB-SS3 revealed that there were no galactoses present in the structure. Mass spectrometric analysis of O-deacylated LOS revealed the presence of multiple species, with the predominant LOS species in this mutant strain formed by the Hex-->(HexNAc)-->Hep2PEA-->KDO2 (where Hex is hexose and HexNAc is N-acetylhexosamine) structure. However, LOS structures with repetitive hexoses, e.g., Hexn-->(HexNAc)-->Hep2PEA-->KDO2 (n = 2, 3, or 4), emanating from one or both heptoses were also identified. Since this mutant cannot synthesize UDP-Gal, these structures must repetitive glucoses. These data suggest that NMB has a glycosyltransferase capable of polymerizing glucose moieties as an alternative biosynthetic pathway to the wild-type lacto-N-neotetrose structure.
PMCID: PMC173335  PMID: 7790063
10.  Tn916-generated, lipooligosaccharide mutants of Neisseria meningitidis and Neisseria gonorrhoeae. 
Infection and Immunity  1994;62(7):2947-2952.
A library of Tn916-generated, tetracycline-resistant (Tc) mutants of the group B Neisseri meningitidis strain NMB was screened by using monoclonal antibodies (MAbs) that recognize structural differences in neisserial lipooligosaccharide (LOS). The LOS of parental strain NMB had a relative molecular mass of 4.5 kDa, reacted with MAbs 3F11 and 6B4 but not with MAb 4C4 or 6E4, and contained a lacto-N-neotetrose unit. Two phenotypically stable mutants, SS3 and R6, altered in LOS, were identified by colony immunoblots, electrophoresis, and Western immunoblots. The LOS of mutant SS3 was 3.4 kDa and reacted with MAbs 4C4 and 6E4 but not MAb 3E11 or 6B4. The LOS of mutant R6 was 3.1 to 3.2 kDa and reacted with MAb 6E4 but not MAb 3F11, 6B4, or 4C4. Thus, the LOSs of the R6 and SS3 mutants were predicted to contain different truncations of the core oligosaccharide. The LOS phenotype of each mutant was linked to Tc(r), as determined by transformation of the parent strain with DNA from the mutant. Southern hybridizations and single-specific-primer PCR revealed in each mutant a single truncated tn916 insertion which had lost genes required for mobilization. Tn916 mutagenesis was used to identify two distinct genetic sites in the meningococcal chromosome involved in biosynthesis of the oligosaccharide chain of LOS and to create genetically defined LOS mutants of N. meningitidis and Neisseria gonorrhoeae.
PMCID: PMC302902  PMID: 7516313
11.  Effect of exogenous sialylation of the lipooligosaccharide of Neisseria gonorrhoeae on opsonophagocytosis. 
Infection and Immunity  1992;60(10):4439-4442.
Serum-sensitive Neisseria gonorrhoeae strains become serum resistant when grown in the presence of a sialic acid precursor, cytidine monophospho-N-acetylneuraminic acid. We examined the abilities of human neutrophils to phagocytose sialylated and nonsialylated gonococci and observed a decrease in the complement-dependent phagocytosis of sialylated gonococci compared with that of nonsialylated gonococci (50.7 versus 25.9% survival at 30 min). This decrease in opsonophagocytosis after sialylation may contribute to the pathogenicity of gonococcal infections.
PMCID: PMC257487  PMID: 1398958
12.  5-(p-aminophenyl)-1,2,3,4-tetrahydroxypentane, a structural component of the modified folate in Sulfolobus solfataricus. 
Journal of Bacteriology  1992;174(14):4576-4582.
The partial characterization of the modified folate present in Sulfolobus solfataricus has been carried out. Separation of ethanol-water extracts of these cells on a DEAE-Sephadex column led to the isolation of a small amount of intact oxidized cofactor, which, when subjected to reductive cleavage with Zn-HCl, produced 6-methylpterin. This indicated that the modified folate in these cells contained a nonmethylated pterin linked, via a methylene group at the C-6 position of the pterin, to an arylamine, as is found in folate. Oxidative cleavage of intact reduced cofactor produced pterin and a single arylamine. The azo dye derivative of this arylamine was prepared and purified by chromatography on a Bio-Gel P-6 column. The resulting purified compound was shown to be readily hydrolyzed in dilute acid to the azo dye derivative of 5-(p-aminophenyl)-1,2,3,4-tetrahydroxypantane, which was, in turn, readily cleaved to 5-(p-aminophenyl)-1,2,3,4- tetrahydroxypentane by Zn-HCl reduction. The stereochemistry of the resulting 5-(p-aminophenyl)-1,2,3,4-tetrahydroxypentane was shown to be ribo, the same as that of the 5-(p-aminophenyl)-1,2,3,4- tetrahydroxypentane moiety found in methanopterin. The complete arylamine side chain of the modified folate thus contains 5-(p-aminophenyl)-1,2,3,4-tetrahydroxypentane attached, via an acid-labile bond, to a currently unidentified substituent. The modified folate present in S. solfataricus thus contains structural features common to both folates and methanopterin.
PMCID: PMC206252  PMID: 1320614
13.  Transsulfuration in archaebacteria. 
Journal of Bacteriology  1991;173(10):3250-3251.
The transfer of sulfur from methionine to cysteine in the archaebacteria Sulfolobus acidocaldarius and Halobacterium marismortui was studied by feeding 34S-labeled methionine to cells and measuring the incorporation of 34S into protein-bound cellular cysteine and methionine by mass spectrometry. It was found that, as are eucaryotes, both of these archaebacteria were able to convert the sulfur of methionine to cysteine.
PMCID: PMC207924  PMID: 1902467
14.  The ubiquitous transcription factor Oct-1 and the liver-specific factor HNF-1 are both required to activate transcription of a hepatitis B virus promoter. 
Molecular and Cellular Biology  1991;11(3):1353-1359.
The liver-specific transcription factor HNF-1 activates transcription of several mammalian hepatocyte-specific genes. The hepatitis B virus preS1 promoter shows hepatocyte specificity, which has been ascribed to binding of HNF-1 to a cognate DNA sequence upstream of the TATA box. We show here that there is an adjacent site that binds the ubiquitous transcription factor Oct-1. Both the Oct-1 and HNF-1 sites are necessary for liver-specific transcription of the preS1 promoter, but neither site alone activates transcription. The Oct-1 site is also necessary for activation of the preS1 promoter in HeLa cells, expressing transfected HNF-1. Our results show that while Oct-1 is not restricted to hepatocytes, it nevertheless can play a critical role in the expression of a liver-specific gene.
PMCID: PMC369406  PMID: 1996097
15.  Expression of anionic glutathione S transferase (GST pi) gene in carcinomas of the uterine cervix and in normal cervices. 
British Journal of Cancer  1991;63(2):191-194.
The aim of the present study was to analyse in invasive carcinomas of the uterine cervix, the anionic glutathione S transferase (GST pi) gene, possibly implicated in the drug resistance of human cancers. Total RNA preparations obtained from invasive cervical cancers (106 specimens), carcinomas in situ (CIS) (three specimens) and normal cervical epitheliums (24 specimens) were analysed by Northern and slot blot hybridisation. A 0.7 kb GST pi transcript band was detected in all the cervical specimens. GST pi mRNA levels were lower in normal cervix (mean: 0.7 +/- 0.1 arbitrary units) than in invasive carcinomas (mean: 2.5 +/- 1.5 units) (Student test P less than 10(-4)). However no significant difference was observed between invasive cancers of advanced stages (III and IV) and those of early stages (I and II). The presence of human papillomavirus in cancers and in normal cervices did not influence significantly the GST pi mRNA level. Neither amplification nor gross rearrangement of GST pi gene could be observed after Southern blot analysis of genomic DNA. In conclusion, our data indicate that the presence of high levels of GST pi transcripts in invasive cancers may be a consequence of the multiple biochemical changes which accompany cervical carcinogenesis.
PMCID: PMC1971764  PMID: 1847644
16.  Activation of class I major histocompatibility complex gene expression by hepatitis B virus. 
Journal of Virology  1990;64(8):4025-4028.
Normal hepatocytes express very few class I major histocompatibility complex (MHC I) molecules, but MHC I expression is elevated in hepatitis B virus (HBV) infection. We report here that hepatoblastoma cells with replicating HBV genomes express three- to fourfold-higher levels of MHC I protein and mRNA than do parent cells without HBV DNA. Transient transfection assays demonstrated that the HBV X protein trans activated transcription from an MHC I promoter and allowed identification of cis elements important for trans activation.
PMCID: PMC249705  PMID: 2164611
17.  Biosynthesis of caldariellaquinone in Sulfolobus spp. 
Journal of Bacteriology  1989;171(12):6610-6616.
The biosynthesis of caldariellaquionone (CQ) was studied in species of Sulfolobus by measuring the incorporation of stable isotopically labeled tyrosines into CQ. By feeding a series of tyrosines labeled with deuterium or 13C and then measuring the extent and position at which label was incorporated into CQ by mass spectrometry, it was shown that more than 95% of the label was incorporated into the benzo[b]thiophen-4,7-quinone moiety of CQ. From the labeling experiments, it is concluded that the benzo[b]thiophen-4,7-quinone is derived as an intact unit from all of the carbons of tyrosine except C-1.
PMCID: PMC210554  PMID: 2512282
18.  Molecular cloning of a small DNA binding protein with specificity for a tissue-specific negative element within the rps1 promoter. 
Nucleic Acids Research  1995;23(7):1165-1169.
A cDNA encoding a specific binding activity for the tissue-specific negative cis-element S1F binding site of spinach rps1 was isolated from a spinach cDNA expression library. This cDNA of 0.7 kb encodes an unusual small peptide of only 70 amino acids, with a basic domain which contains a nuclear localization signal and a putative DNA binding helix. This protein, named S1Fa, is highly conserved between dicotyledonous and monocotyledonous plants and may represent a novel class of DNA binding proteins. The corresponding mRNA is accumulated more in roots and in etiolated seedlings than in green leaves. This expression pattern is correlated with the tissue-specific function of the S1F binding site which represses the rps1 promoter preferentially in roots and in etiolated plants.
PMCID: PMC306826  PMID: 7739894
20.  Structure and expression of the nuclear gene coding for the plastid CS1 ribosomal protein from spinach. 
Nucleic Acids Research  1992;20(16):4153-4157.
The chloroplast ribosomal protein CS1 is an essential component of the plastids translational machinery involved in translation initiation. Southern analysis suggests that the corresponding nuclear gene is present in one copy in the spinach genome. We have isolated and sequenced the gene (rps1) to study its expression at the transcriptional level. The gene consists of 7 exons and 6 introns including an unusually large intron in the 5' coding region. No canonical TATA-box is found in the 5' upstream region of the gene. rps1 transcripts are detected early during germination and a significant accumulation is observed after the protrusion of the radicle. CS1 mRNAs are present in all organs of young seedlings although there are dramatic differences in the steady state level of the mRNAs between leaves and roots tissues. Transcripts accumulate independently of the presence or absence of light. Band shift analysis shows that the +1, -400 bp region of the gene can bind different sets of proteins isolated from roots and leaves nuclei. We suggest that the expression of the housekeeping plastid-related rps1 gene is regulated in a tissue-specific manner by transcriptional trans-acting factors.
PMCID: PMC334119  PMID: 1508710

Results 1-20 (20)