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61.
Son Radu Shahilah Abdul Mutalib Gulam Rusul Zainori Ahmad Tadaaki Morigaki Norio Asai Yung Bu Kim Jun Okuda Mitsuaki Nishibuchi 《Applied microbiology》1998,64(3):1153-1156
Twelve strains of Escherichia coli O157:H7 were isolated from 9 of 25 beef samples purchased from retail stores in Malaysia. These strains produced Shiga toxin 2 with or without Shiga toxin 1 and had the eae gene and a 60-MDa plasmid. The antibiograms and the profiles of the arbitrarily primed PCR of the strains were diverse, suggesting that the strains may have originated from diverse sources. 相似文献
62.
The association of the HLA class III region with many diseases motivates the investigation of unidentified genes in the 30-kb segment between complement component genesBfandC4. RD,which codes for a putative RNA binding protein, is 205 bp downstream ofBf. SKI2W(HGMW-approved symbol SKIV2L), a DEVH-box gene probably involved in RNA turnover, is 171 bp downstream ofRD(HGMW-approved symbol D6S45).RP1(HGMW-approved symbol D6S60E) is located 611 bp upstream ofC4.The DNA sequence between humanRDandRP1was determined and the exon–intron structure ofSKI2Welucidated.SKI2Wconsists of 28 exons. The putative RNA helicase domain of Ski2w is encoded by 9 exons. Further analysis of the 2.5-kb intergenic sequence betweenSKI2WandRP1led to the discovery ofDOM3Z.The full-length cDNA sequence ofDOM3Zencodes 396 amino acids with a leucine zipper motif. Dom3z-related proteins are present in simple and complex eukaryotes. InCaenorhabditis elegans,Dom3z-related protein could be involved in the development of germ cells. HumanRD–SKI2WandDOM3Z–RP1are arranged as two head-to-head oriented gene pairs with unmethylated CpG sequences at the common 5′ regulatory region of each gene pair. The ubiquitous expression pattern suggests that these four genes are probably housekeeping genes. 相似文献
63.
Presence or absence of N-acetylneuraminic acid (Neu5Ac) can change a
sialylated glycoprotein's serum half-life and possibly its function. We
evaluated the linearity, sensitivity, reproducibility, and accuracy of a
HPAEC/PAD method to determine its suitability for routine simultaneous
analysis of Neu5Ac and N-glycolylneuraminic acid (Neu5Gc). An effective
internal standard for this analysis is 3-deoxy-d-glycero-d-
galacto-2-nonulosonic acid (KDN). We investigated the effect of the Au
working electrode recession and determined that linear range and
sensitivity were dependent on electrode recession. Using an electrode that
was 350 &mgr;m recessed from the electrode block, the minimum detection
limits of Neu5Ac, KDN, and Neu5Gc were 2, 5, and 2 pmol, respectively, and
were reduced to 1, 2, and 0.5 pmol using a new electrode. The response of
standards was linear from 10 to 500 pmol (r2>0.99) regardless of
electrode recession. When Neu5Ac, KDN, and Neu5Gc (200 pmol each) were
analyzed repetitively for 48 h, area RSDs were <3%. Reproducibility was
unaffected when injections of glycoprotein neuraminidase and acid
digestions were interspersed with standard injections. Area RSDs of Neu5Ac
and Neu5Gc improved when the internal standard was used. We determined the
precision and accuracy of this method for both a recessed and a new working
electrode by analyzing Neu5Ac and Neu5Gc contents of bovine fetuin and
bovine and human transferrins. Results were consistent with published
values and independent of the working electrode. The sensitivity,
reproducibility, and accuracy of this method make it suitable for direct
routine analysis of glycoprotein Neu5Ac and Neu5Gc contents.
相似文献
64.
Yat Ming Lau Tak Hong Cheung Winnie Yeo Frankie Mo Mei Yung Yu Kun Min Lee Wendy C. S. Ho Apple C. M. Yeung Priscilla T. Y. Law Paul K. S. Chan 《PloS one》2015,10(4)
High-risk human papillomavirus (HPV) types are associated with cervical cancer. It is well established that individual HPV types vary in oncogenicity, but current data on their prognostic implication remain controversial. We examined the association between HPV types/species and the survival of 236 Chinese women aged 26–87 (mean 54.4) years after receiving primary treatment for cervical cancer. Overall, 45.8% were of FIGO stage I, 41.9% stage II, and 12.3% stage III. The four most prevalent types found were HPV-16 (60.2%), HPV-18 (21.6%), HPV-52 (11.9%), and HPV-58 (9.3%). Overall, 19.5% of patients had multiple-type infections, 78.4% harboured one or more alpha-9 species, and 28.8% harboured one or more alpha-7 species. After a median follow-up of 8.0 years, 156 (66.1%) patients survived. The 3-year overall survival rate was 75.5%. Factors independently associated with a poorer 3-year overall survival were age >60 years, tumour size >4 cm, lymph node involvement and treatment with radiotherapy+/-chemotherapy. Univariate analysis showed HPV-16 single-type infection was associated with a marginally poorer disease-specific survival (71.6% vs. 87.0%, HR: 1.71, 95% CI = 1.01–2.90), whereas non-HPV-16 alpha-9 species was associated with a better disease-specific survival (90.0% vs. 76.2%, HR: 0.36, 95% CI = 0.16–0.79). However, on multivariate analysis, HPV infection status irrespective of different grouping methods, including individual types, species, single-type or co-infection, did not carry any significant prognostic significance. In conclusion, we did not observe any association between infection with a particular HPV type/species and survival. An HPV type-based stratification in treatment and follow-up plan could not be recommended. 相似文献
65.
Kavita Venkataraman Luor Shyuan Maudrene Tan Dianne Carrol Tan Bautista Konstadina Griva Yasmin Laura Marie Zuniga Mohamed Amir Yung Seng Lee Jeannette Lee E. Shyong Tai Eric Yin Hao Khoo Hwee Lin Wee 《PloS one》2015,10(9)
Background
Emotional distress is an important dimension in diabetes, and several instruments have been developed to measure this aspect. The Problem Areas in Diabetes (PAID) scale is one such instrument which has demonstrated validity and reliability in Western populations, but its psychometric properties in Asian populations have not been examined.Methods
This was a secondary analysis of data from patients with Type 2 diabetes mellitus recruited through convenience sampling from a diabetes specialist outpatient clinic in Singapore. The following psychometric properties were assessed: Construct validity through confirmatory factor analysis (CFA) and Rasch analysis, concurrent validity through correlation with related scales (Kessler Psychological Distress Scale, Diabetes Health Profile—psychological distress, Audit of Diabetes Dependent Quality of Life), reliability through assessment of internal consistency and floor and ceiling effects, and sensitivity by estimating effect sizes for known clinical and social functioning groups.Results
203 patients with mean age of 45±12 years were analysed. None of the previously published model structures achieved a good fit on CFA. On Rasch analysis, four items showed poor fit and were removed. The abridged 16-item PAID mapped to a single latent trait, with a high degree of internal consistency (Cronbach ɑ 0.95), but significant floor effect (24.6% scoring at floor). Both 20-item and 16-item PAID scores were moderately correlated with scores of related scales, and sensitive to differences in clinical and social functioning groups, with large effect sizes for glycemic control and diabetes related complications, nephropathy and neuropathy.Conclusion
The abridged 16-item PAID measures a single latent trait of emotional distress due to diabetes whereas the 20-item PAID appears to measures more than one latent trait. However, both the 16-item and 20-item PAID versions are valid, reliable and sensitive for use among Singaporean patients with diabetes. 相似文献66.
Yung Su Kim Mei Yang Wai-Kin Mat Shui-Ying Tsang Zhonghua Su Xianfei Jiang Siu-Kin Ng Siyu Liu Taobo Hu Frank Pun Yanhui Liao Jinsong Tang Xiaogang Chen Wei Hao Hong Xue 《PloS one》2015,10(11)
Substance dependence is a frequently observed comorbid disorder in schizophrenia, but little is known about genetic factors possibly shared between the two psychotic disorders. GABRB2, a schizophrenia candidate gene coding for GABAA receptor β2 subunit, is examined for possible association with heroin dependence in Han Chinese population. Four single nucleotide polymorphisms (SNPs) in GABRB2, namely rs6556547 (S1), rs1816071 (S3), rs18016072 (S5), and rs187269 (S29), previously associated with schizophrenia, were examined for their association with heroin dependence. Two additional SNPs, rs10051667 (S31) and rs967771 (S32), previously associated with alcohol dependence and bipolar disorder respectively, were also analyzed. The six SNPs were genotyped by direct sequencing of PCR amplicons of target regions for 564 heroin dependent individuals and 498 controls of Han Chinese origin. Interestingly, it was found that recombination between the haplotypes of all-derived-allele (H1; OR = 1.00) and all-ancestral-allele (H2; OR = 0.74) at S5-S29 junction generated two recombinants H3 (OR = 8.51) and H4 (OR = 5.58), both conferring high susceptibility to heroin dependence. Additional recombination between H2 and H3 haplotypes at S1-S3 junction resulted in a risk-conferring haplotype H5 (OR = 1.94x109). In contrast, recombination between H1 and H2 haplotypes at S3-S5 junction rescued the risk-conferring effect of recombination at S5-S29 junction, giving rise to the protective haplotype H6 (OR = 0.68). Risk-conferring effects of S1-S3 and S5-S29 crossovers and protective effects of S3-S5 crossover were seen in both pure heroin dependent and multiple substance dependence subgroups. In conclusion, significant association was found with haplotypes of the S1-S29 segment in GABRB2 for heroin dependence in Han Chinese population. Local recombination was an important determining factor for switching haplotypes between risk-conferring and protective statuses. The present study provide evidence for the schizophrenia candidate gene GABRB2 to play a role in heroin dependence, but replication of these findings is required. 相似文献
67.
68.
Park IS Park JU Seo MJ Kim MJ Lee HH Kim SR Kang BW Choi YH Joo WH Jeong YK 《Journal of microbiology (Seoul, Korea)》2010,48(6):836-841
A fibrinolytic enzyme of the mushroom, Schizophyllum commune was purified with chromatographic methods, including a DEAE-Sephadex A-50 ion-exchange column and gel filtrations with Sephadex
G-75 and Sephadex G-50 columns. The analysis of fibrin-zymography and SDS-PAGE showed that the enzyme was a monomeric subunit
that was estimated to be approximately 17 kDa in size. The fibrinolytic activity of the enzyme in plasminogen-rich and plasminogen-free
fibrin plates was 1.25 and 0.44 U/ml, respectively. The N-terminal amino acid sequence of the purified enzyme was identified
as HYNIXNSWSSFID, which was highly distinguished from known fibrinolytic enzymes. The relative activity of the purified enzyme
with an addition of 5 mM EDTA, Phosphoramidon, and Bestatin was about 76, 64, and 52%, respectively, indicating that it is
a metalloprotease. The optimum temperature for the purified enzyme was approximately 45°C, and over 87% of the enzymatic activity
was maintained as a stable state in a pH range from 4.0 to 6.0. Therefore, our results suggest that the potential thrombolytic
agent from S. commune is a unique type of fibrinolytic enzyme. 相似文献
69.
Eun Hye Kim Kyeung Hee Cho Yung Mi Lee Joung Han Yim Hong Kum Lee Jang-Cheon Cho Soon Gyu Hong 《Journal of microbiology (Seoul, Korea)》2010,48(4):426-432
A new approach for enrichment culture was applied to obtain cold-active protease-producing bacteria for marine and terrestrial samples from Svalbard, Norway. The method was developed for the enrichment of bacteria by long-term incubation at low temperatures in semi-solid agar medium containing meat pieces as the main source of carbon and energy. ZoBell and 0.1× nutrient broth were added for marine and terrestrial microorganisms, respectively, to supply basal elements for growth. One to three types of colonies were observed from each enrichment culture, indicating that specific bacterial species were enriched during the experimental conditions. Among 89 bacterial isolates, protease activity was observed from 48 isolates in the screening media containing skim milk. Good growth was observed at 4°C and 10°C while none of the isolates could grow at 37°C. At low temperatures, enzyme activity was equal to or higher than activity at higher temperatures. Bacterial isolates were included in the genera Pseudoalteromonas (33 isolates), Arthrobacter (24 isolates), Pseudomonas (16 isolates), Psychrobacter (6 isolates), Sphingobacterium (6 isolates), Flavobacterium (2 isolates), Sporosarcina (1 isolate), and Stenotrophomonas (1 isolate). Protease activity was observed from Pseudoalteromonas (33 isolates), Pseudomonas (10 isolates), Arthrobacter (4 isolates), and Flavobacterium (1 isolate). 相似文献
70.
Phosphatidylinositol 3-kinase (PI3K) mediates receptor tyrosine kinase and G protein coupled receptor (GPCR) signaling by phosphorylating phosphoinositides to elicit various biological responses. Gαq has previously been shown to inhibit class IA PI3K by interacting with the p110α subunit. However, it is not known if PI3Ks can associate with other Gαq family members such as Gα16. Here, we demonstrated that class IA PI3Ks, p85/p110α and p85/p110β, could form stable complexes with wild type Gα16 and its constitutively active mutant (Gα16QL) in HEK293 cells. In contrast, no interaction between Gα16 and class IB PI3K was observed. The Gα16/p110α signaling complex could be detected in hematopoietic cells that endogenously express Gα16. Overexpression of class I PI3Ks did not inhibit Gα16QL-induced IP3 production and, unlike p63RhoGEF, class IA PI3Ks did not attenuate the binding of PLCβ2 to Gα16QL. On the contrary, the function of class IA PI3Ks was suppressed by Gα16QL as revealed by diminished production of PIP3 as well as inhibition of EGF-induced Akt phosphorylation. Taken together, these results suggest that Gα16 can bind to class IA PI3Ks and inhibit the PI3K signaling pathway. 相似文献