826
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Si W, Gong J, Tsao R, Zhou T, Yu H, Poppe C, Johnson R, Du Z. Antimicrobial activity of essential oils and structurally related synthetic food additives towards selected pathogenic and beneficial gut bacteria. J Appl Microbiol 2006; 100:296-305. [PMID: 16430506 DOI: 10.1111/j.1365-2672.2005.02789.x] [Citation(s) in RCA: 173] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
AIMS To assess the potential of essential oils and structurally related synthetic food additives in reducing bacterial pathogens in swine intestinal tract. METHODS AND RESULTS The antimicrobial activity of essential oils/compounds was measured by determining the inhibition of bacterial growth. Among 66 essential oils/compounds that exhibited > or =80% inhibition towards Salmonellatyphimurium DT104 and Escherichia coli O157:H7, nine were further studied. Most of the oils/compounds demonstrated high efficacy against S. typhimurium DT104, E. coli O157:H7, and E. coli with K88 pili with little inhibition towards lactobacilli and bifidobacteria. They were also tolerant to the low pH. When mixed with pig cecal digesta, these oils/compounds retained their efficacy against E. coli O157:H7. In addition, they significantly inhibited E. coli and coliform bacteria in the digesta, but had little effect on the total number of lactobacilli and anaerobic bacteria. CONCLUSIONS Some essential oils/compounds demonstrated good potential, including efficacy, tolerance to low pH, and selectivity towards bacterial pathogens, in reducing human and animal bacterial pathogens in swine intestinal tract. SIGNIFICANCE AND IMPACT OF THE STUDY This study has identified candidates of essential oils/compounds for in vivo studies to develop antibiotic substitutes for the reduction of human and animal bacterial pathogens in swine intestinal tract.
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827
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Yu H, Shimizu T, Hsieh Y, Suzuki T, Choudhry M, Bland K, Schwacha M, Chaudry I. Differential expression of tissue estrogen receptor subtype α and β and their role in the regulation of neutrophil infiltration following trauma-hemorrhage. J Surg Res 2006. [DOI: 10.1016/j.jss.2005.11.193] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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828
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Hersch SM, Gevorkian S, Marder K, Moskowitz C, Feigin A, Cox M, Como P, Zimmerman C, Lin M, Zhang L, Ulug AM, Beal MF, Matson W, Bogdanov M, Ebbel E, Zaleta A, Kaneko Y, Jenkins B, Hevelone N, Zhang H, Yu H, Schoenfeld D, Ferrante R, Rosas HD. Creatine in Huntington disease is safe, tolerable, bioavailable in brain and reduces serum 8OH2'dG. Neurology 2006; 66:250-2. [PMID: 16434666 DOI: 10.1212/01.wnl.0000194318.74946.b6] [Citation(s) in RCA: 217] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
In a randomized, double-blind, placebo-controlled study in 64 subjects with Huntington disease (HD), 8 g/day of creatine administered for 16 weeks was well tolerated and safe. Serum and brain creatine concentrations increased in the creatine-treated group and returned to baseline after washout. Serum 8-hydroxy-2'-deoxyguanosine (8OH2'dG) levels, an indicator of oxidative injury to DNA, were markedly elevated in HD and reduced by creatine treatment.
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829
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Abstract
Normal human somatic cells contain 46 chromosomes (22 pairs of autosomes and two sex chromosomes). Chromosome missegregation leads to abnormal numbers of chromosomes or aneuploidy. This form of genetic instability alters the dosages of large subsets of genes, which can result in severe disease phenotypes. Most human cancer cells are aneuploid. It is generally believed that aneuploidy contributes to cancer formation. The spindle checkpoint is a cell-cycle surveillance mechanism that ensures the fidelity of chromosome segregation during mitosis and meiosis. In this article, we review our current understanding of the molecular basis of the spindle checkpoint and the recent evidence that links the malfunction of this checkpoint to aneuploidy and tumorigenesis.
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830
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Huang J, Parish R, Yu H, Bass PF, Mansi I, Kennen E, Davis T, Carden D. 266 NON-HIGH-DENSITY LIPOPROTEIN CHOLESTEROL IN THE METABOLIC SYNDROME.:. J Investig Med 2006. [DOI: 10.2310/6650.2005.x0008.265] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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831
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Low KH, Liu X, Yu H. Design and implementation of NTU wearable exoskeleton as an enhancement and assistive device. Appl Bionics Biomech 2006. [DOI: 10.1533/abbi.2006.0030] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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832
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Abstract
Recent insights into the Smith-Lemli-Opitz syndrome. The Smith-Lemli-Opitz syndrome (SLOS) is an autosomal recessive multiple congenital anomaly/mental retardation disorder caused by an inborn error of post-squalene cholesterol biosynthesis. Deficient cholesterol synthesis in SLOS is caused by inherited mutations of 3beta-hydroxysterol-Delta7 reductase gene (DHCR7). DHCR7 deficiency impairs both cholesterol and desmosterol production, resulting in elevated 7DHC/8DHC levels, typically decreased cholesterol levels and, importantly, developmental dysmorphology. The discovery of SLOS has led to new questions regarding the role of the cholesterol biosynthesis pathway in human development. To date, a total of 121 different mutations have been identified in over 250 patients with SLOS who represent a continuum of clinical severity. Two genetic mouse models have been generated which recapitulate some of the developmental abnormalities of SLOS and have been useful in elucidating the pathogenesis. This mini review summarizes the recent insights into SLOS genetics, pathophysiology and potential therapeutic approaches for the treatment of SLOS.
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833
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Ferrante KL, Shefner J, Zhang H, Betensky R, O'Brien M, Yu H, Fantasia M, Taft J, Beal MF, Traynor B, Newhall K, Donofrio P, Caress J, Ashburn C, Freiberg B, O'Neill C, Paladenech C, Walker T, Pestronk A, Abrams B, Florence J, Renna R, Schierbecker J, Malkus B, Cudkowicz M. Tolerance of high-dose (3,000 mg/day) coenzyme Q10 in ALS. Neurology 2005; 65:1834-6. [PMID: 16344537 DOI: 10.1212/01.wnl.0000187070.35365.d7] [Citation(s) in RCA: 122] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
An open-label dose-escalation trial was performed to assess the safety and tolerability of high doses of coenzyme Q10 (CoQ10) in ALS. CoQ10, a cofactor in mitochondrial electron transfer, may improve the mitochondrial dysfunction in ALS. In this study, CoQ10 was safe and well tolerated in 31 subjects treated with doses as high as 3,000 mg/day for 8 months.
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834
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Yu H, Yin J, Li H, Yang S, Shen Z. Construction and selection of the novel recombinant Escherichia coli strain for poly(beta-hydroxybutyrate) production. J Biosci Bioeng 2005; 89:307-11. [PMID: 16232750 DOI: 10.1016/s1389-1723(00)88950-1] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/1999] [Accepted: 11/29/1999] [Indexed: 11/19/2022]
Abstract
Heterogeneous cloning of Vitreoscilla hemoglobin gene (vgb), lytic genes of phage lambda with S amber mutation (S(-)RRz) and PHB biosynthetic genes (phbCAB) in the same host strain E. coli JM105 was carried out for production of poly(beta-hydroxybutyrate) (PHB). A superior novel strain, VG1 (pTU14), was constructed and selected, which contained the vgb gene in the chromosomal DNA and the plasmid pTU14 containing S(-)RRz and phbCAB genes. When cultured in 100 ml of LBG medium in a 300-ml flask, all of the exogenous genes in VG1 (pTU14) were expressed. The cell concentration of VG1 (pTU14) grown by batch culture in a flask reached 10.2 gl(-1); PHB concentration, PHB content and PHB yield, which is the ratio of the PHB accumulation to the glucose consumption, were 8.54 gl(-1), 84% and 0.43 gg(-1), respectively. When cultured by batch-feeding of glucose in a 300-ml shaking flask, the cell concentration and PHB content reached 26 gl(-1) and over 96%, respectively.
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835
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Yu H, Sheikholeslami R, Doherty W. Calcium oxalate crystallization in silica and sugar solutions-characterization of crystal phases and habits. POWDER TECHNOL 2005. [DOI: 10.1016/j.powtec.2005.04.043] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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836
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Yu H, Gan LH, Hu X, Venkatraman SS, Tam KC, Gan YY. A Novel Amphiphilic Double-[60]Fullerene-Capped Triblock Copolymer. Macromolecules 2005. [DOI: 10.1021/ma051833i] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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837
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Dong Y, Gao W, Nan H, Yu H, Li F, Duan W, Wang Y, Sun B, Qian R, Tuomilehto J, Qiao Q. Prevalence of Type 2 diabetes in urban and rural Chinese populations in Qingdao, China. Diabet Med 2005; 22:1427-33. [PMID: 16176207 DOI: 10.1111/j.1464-5491.2005.01658.x] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
AIMS To determine the prevalence of diabetes in the Chinese adult population in rural and urban areas of Qingdao city. METHODS A population-based cross-sectional study of diabetes was performed in 12 436 (5346 men) Chinese adults (20-74 years old) from 2001 to 2002. Fasting capillary whole blood glucose test (FCG) was performed in all participants and a 2-h 75-g oral glucose tolerance test in those with FCG > or = 6.1 mmol/l following initial screening. The 1999 World Health Organization diagnostic criteria for diabetes were used. RESULTS The age-standardized prevalence of diabetes was 6.1% (4.1% for undiagnosed and 2.1% for previously known diabetes) in adults aged 20-74 years. Diabetes prevalence increased with age up to the oldest age group (70-74); in subjects over 50 years of age, the prevalence reached 10%. Men tended to have a higher prevalence of known diabetes than women, whereas the prevalence of undiagnosed diabetes was lower in men than in women (4.6% vs. 3.3%, d.f. = 1, P = 0.001). Diabetes was more prevalent in the urban than in the rural population (6.9% vs. 5.6%, d.f. = 1, P < 0.001). However, the proportion of undiagnosed diabetes was higher in the rural than in the urban areas (70.5% vs. 58.0%, d.f. = 1, P < 0.001). CONCLUSIONS The prevalence of Type 2 diabetes in Qingdao city is moderately high, but much higher than reported in 1996. The large proportion of undiagnosed cases of diabetes indicates the lack of public awareness of diabetes and shortage of medical facilities. In view of the huge population in China, the results of this study emphasize the need to improve the early detection and prevention of diabetes in China to prevent the emerging diabetes epidemic.
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838
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Beeghly A, Katsaros D, Chen H, Fracchioli S, Zhang Y, Massobrio M, Risch H, Jones B, Yu H. Glutathione S-transferase polymorphisms and ovarian cancer treatment and survival. Gynecol Oncol 2005; 100:330-7. [PMID: 16199080 DOI: 10.1016/j.ygyno.2005.08.035] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2005] [Revised: 08/25/2005] [Accepted: 08/26/2005] [Indexed: 11/28/2022]
Abstract
OBJECTIVE Members of the glutathione S-transferase (GST) family have been shown to have functional polymorphisms that may affect drug metabolism and influence the effects of chemotherapy and survival from cancer. GSTM1, GSTT1, and GSTP1 genotypes were evaluated for their role in ovarian cancer treatment and survival. METHODS DNA was extracted from tumor tissues of 215 patients diagnosed with primary epithelial ovarian cancer. GSTM1 and GSTT1 genotypes were determined by multiplex PCR; GSTP1 genotypes were assessed with PCR-RFLP. Associations between GST polymorphisms and risk of ovarian cancer progression or death were analyzed using Cox proportional hazards regression; subgroups of patients receiving different chemotherapeutics were also evaluated. RESULTS GST polymorphisms were not found to be associated with patient or tumor characteristics or response to treatment. However, GSTM1 null patients were less likely to have disease progression (HR: 0.65, 95% CI: 0.43-0.99) or to die (HR: 0.68, 95% CI: 0.45-1.03) compared to patients with GSTM1. Patients with GSTM1 null and GSTP1 ile/val or val/val (reduced function) had a further reduction in risk of disease progression compared to patients with GSTM1 or GSTP1 ile/ile (HR: 0.42, 95% CI: 0.24-0.75). A similar association was also suggested for overall survival (HR: 0.61, 95% CI: 0.36-1.05). Subgroup analyses indicated that the effects of GST on survival were more pronounced among patients treated with specific chemotherapeutics. CONCLUSION These findings support the idea that reduced GST function may improve ovarian cancer survival after post-operative chemotherapy; evaluation of GST functional polymorphisms may help to predict ovarian cancer prognosis.
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839
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Su XJ, Yu H, Zhou T, Li XZ, Gong J, Chu CL. First Report of Alternaria raphani Causing Black Patches on Chinese Radish During Postharvest Storage in Canada. PLANT DISEASE 2005; 89:1015. [PMID: 30786654 DOI: 10.1094/pd-89-1015c] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
During November of 2003, Chinese radishes (Raphanus sativus cv. Taibai) harvested in St. Catharines, Ontario and stored in less than 1°C with 98% relative humidity (RH) and 5°C with 96% RH showed symptoms of black and dark brown, irregular patches, with or without decay. The symptoms were closely associated with skin wounds and damaged root hairs. Fungal DNA was extracted from discolored skin samples peeled from a radish, and 18S rRNA genes were amplified with fungal-specific PCR primers (1) EF4f (5'-ggaagggrtgtatttattag-3') and EF3r (5'-tcctctaaatgaccagtttg-3'). The cloned genes were sequenced using the primer EF4f and compared directly with nonredundant nucleotides in GenBank with BLAST. The results indicated that more than 75% of the fungal microflora on the diseased radish were Alternaria spp. Alternaria sp. was successfully isolated from discolored and decayed radish tissues. Morphological and molecular identification indicated that the isolated Alternaria sp. cultures belong to A. raphani, which was previously reported to cause leaf and pod blight on radish (2). For pathogenicity studies, a spore suspension (1 × 105 conidia/ml) obtained from a 4-week-old A. raphani culture was used to inoculate 'Taibai' Chinese radish tissues, including inner tissues and wounded and nonwounded skin. All tests were carried out at room temperature (22 to 24°C). On inner tissue and wounded skin, symptoms of dark brown-to-black patches appeared 2 days after inoculation and progressed with time. No symptoms developed on the noninoculated control or the nonwounded, inoculated treatment. A. raphani was reisolated from symptomatic tissue. Further evidence of pathogenicity was obtained by an additional inoculation and observation of symptoms. The results indicated that A. raphani was the causal agent of the black patches observed on Chinese radish, and to our knowledge, this is the first report that A. raphani could cause a postharvest disease on Chinese radish in storage. References: (1) J. D. Van Elsas et al. J. Microbiol. Methods 43:133, 2000. (2) M. S. Sangwan et al. J. Mycol. Plant Pathol. 32:125, 2002.
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840
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Wright VL, Olan W, Dick B, Yu H, Alberts-Grill N, Latour LL, Baird AE. Assessment of CE-MRA for the rapid detection of supra-aortic vascular disease. Neurology 2005; 65:27-32. [PMID: 16009882 DOI: 10.1212/01.wnl.0000167606.81882.68] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
BACKGROUND Contrast-enhanced MR angiography (CE-MRA) using a combined head and neck coil permits non-invasive imaging of the vasculature from the aortic arch through to the Circle of Willis in less than 2 minutes. OBJECTIVE To determine the accuracy of CE-MRA for the detection of vascular pathology, in particular vascular stenoses, using digital subtraction angiography (DSA) as the gold standard. METHODS In a prospective study of 81 patients referred for DSA, CE-MRA and DSA studies were performed within 72 hours of each other. CE-MRA was performed on a 1.5 Tesla clinical MRI scanner using a five-channel neurovascular array (head and neck coil), with dynamic tracking of the IV gadolinium bolus. CE-MRAs and DSA films were read by two interventional neuroradiologists blinded to the clinical presentation of the patient. RESULTS On DSA, there were 77 vascular stenoses > or =50% identified, 51 extracranial and 26 intracranial. The overall sensitivity of CE-MRA using the neurovascular array for the detection of vascular stenoses > or =50% was 57% (95% CI: 46 to 68%) with a specificity of 98% (97 to 99%). The sensitivity for the detection of extracranial vascular stenoses > or =50% was 82% (72 to 93%) with a specificity of 97% (96 to 98%). However, the sensitivity for the detection of intracranial vascular stenoses > or =50% was only 8% (0 to 18%), with a specificity of 99% (98 to 100%). CONCLUSIONS At this stage Contrast-enhanced MR angiography using a neurovascular coil shows promise as a rapid, specific, and noninvasive screening method for extracranial vascular disease, but not for intracranial vascular disease.
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841
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Rubinchik S, Woraratanadharm J, Yu H, Dong JY. New complex Ad vectors incorporating both rtTA and tTS deliver tightly regulated transgene expression both in vitro and in vivo. Gene Ther 2005; 12:504-11. [PMID: 15660114 DOI: 10.1038/sj.gt.3302437] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Regulation of transgene expression is a major goal of gene therapy research. Previously, we have developed a complex adenovirus (Ad) vector with tetracycline-regulated expression of a Fas ligand (FasL)-green fluorescent protein (GFP) fusion protein. This vector delivered high levels of activity that was regulated by doxycycline. However, this regulation was limited by the low but significant background activity of the TRE promoter. Recently, the Tet-regulated transcriptional silencer, tTS, was reported to suppress efficiently basal TRE activity without affecting induced expression levels. Here, we report development of Ad vectors that incorporate tTS in combination with that of reverse transactivator (rtTA) coupled with TRE promoter driving transgene expression. Incorporation of tTS improved control of transgene expression in vitro, so that an induction range of over three orders of magnitude was achieved in some cell lines. Effective regulation of transgene expression was also seen in a mouse model in vivo, following systemic vector delivery. In the case of FasL-GFP expression, significant improvement in the control of apoptotic activity both in vitro and in a mouse hepatotoxicity model was demonstrated when using rtTA-tTS vectors. In conclusion, a highly effective transgene regulation system, deliverable by a single adenoviral vector, is now available.
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842
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Leppert JT, Lam JS, Yu H, Seligson DB, Dong J, Horvath S, Pantuck AJ, Belldegrun AS, Figlin RA. Targeting the vascular endothelial growth factor pathway in renal cell carcinoma: A tissue array based analysis. J Clin Oncol 2005. [DOI: 10.1200/jco.2005.23.16_suppl.4536] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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843
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Lam JS, Leppert JT, Yu H, Seligson DB, Dong J, Horvath S, Pantuck AJ, Figlin RA, Belldegrun AS. Expression of the vascular endothelial growth factor family in tumor dissemination and disease free survival in clear cell renal cell carcinoma. J Clin Oncol 2005. [DOI: 10.1200/jco.2005.23.16_suppl.4538] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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844
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Kong XH, Yu H, Xuan CH, Wang JZ, Chen QM, Geng YQ. The requirements and mechanism for capsid assembly and budding of bovine foamy virus. Arch Virol 2005; 150:1677-84. [PMID: 15834655 DOI: 10.1007/s00705-005-0518-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2004] [Accepted: 01/25/2005] [Indexed: 11/26/2022]
Abstract
Little is known about assembly of non-primate foamy virus (FV) such as bovine foamy virus (BFV). To help determine the requirements for assembly of BFV, we constructed BFV-Gag expression plasmids containing all or part of the gag gene, with or without modification by addition of myristate (Myr). Each construct was transfected alone, and with pFenv, into Sf-9 insect cells. The results showed that only the entire Gag could transit through nucleus, which is required for BFV viral assembly in the cytoplasm. Unlike other retroviruses (but like primate foamy viruses), BFV requires the coexpression of the Env protein for viral particle budding. In the case of BFV, this occurs at the plasma membrane rather than the endoplasmic reticulum (ER), due to lack of a functional ER retrieval signal (ERRS). The results also showed that addition of a Myr-membrane targeting signal to the C-terminus of Gag could restore the budding from plasma membrane, implying that Myr-membrane targeting signal could substitute for Env protein in budding.
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845
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Kornaat PR, Reeder SB, Koo S, Brittain JH, Yu H, Andriacchi TP, Gold GE. MR imaging of articular cartilage at 1.5T and 3.0T: comparison of SPGR and SSFP sequences. Osteoarthritis Cartilage 2005; 13:338-44. [PMID: 15780647 DOI: 10.1016/j.joca.2004.12.008] [Citation(s) in RCA: 108] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/27/2004] [Accepted: 12/24/2004] [Indexed: 02/02/2023]
Abstract
OBJECTIVE To compare articular cartilage signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and thickness measurements on a 1.5 T and a 3.0 T magnetic resonance (MR) scanner using three-dimensional spoiled gradient recalled echo (3D-SPGR) and two 3D steady-state free precession (SSFP) sequences. METHODS Both knees of five volunteers were scanned at 1.5 T and at 3.0 T using a transmit-receive quadrature extremity coil. Each examination consisted of a sagittal 3D-SPGR sequence, a sagittal fat suppressed 3D-SSFP (FS-SSFP) sequence, and a sagittal Dixon 3D-SSFP sequence. For quantitative analysis, we compared cartilage SNR and CNR efficiencies, as well as average cartilage thickness measurements. RESULTS For 3D-SPGR, cartilage SNR efficiencies at 3.0 T increased compared to those at 1.5 T by a factor of 1.83 (range: 1.40-2.09). In comparison to 3D-SPGR, the SNR efficiency of FS-SSFP increased by a factor of 2.13 (range: 1.81-2.39) and for Dixon SSFP by a factor of 2.39 (range: 1.95-2.99). For 3D-SPGR, CNR efficiencies between cartilage and its surrounding tissue increased compared to those at 1.5 T by a factor of 2.12 (range: 1.75-2.47), for FS-SSFP by a factor 2.11 (range: 1.58-2.80) and for Dixon SSFP by a factor 2.39 (range 2.09-2.83). Average cartilage thicknesses of load bearing regions were not different at both field strengths or between sequences (P>0.05). Mean average cartilage thickness measured in all knees was 2.28 mm. CONCLUSION Articular cartilage imaging of the knee on a 3.0 T MR scanner shows increased SNR and CNR efficiencies compared to a 1.5 T scanner, where SSFP-based techniques show the highest increase in SNR and CNR efficiency. There was no difference between average cartilage thickness measurements performed at the 1.5 T and 3.0 T scanners or between the three different sequences.
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846
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Gandia C, Yu H, Santiago S, Coats E, Defaria W, Ruiz P, Tzakis A, Kleiner G. Bone marrow-derived mesenchymal stem cells augment tissue engineered enterocytes. Biol Blood Marrow Transplant 2005. [DOI: 10.1016/j.bbmt.2004.12.037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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847
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Tu AHT, Clapper B, Schoeb TR, Elgavish A, Zhang J, Liu L, Yu H, Dybvig K. Association of a major protein antigen of Mycoplasma arthritidis with virulence. Infect Immun 2005; 73:245-9. [PMID: 15618160 PMCID: PMC538968 DOI: 10.1128/iai.73.1.245-249.2005] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Mycoplasma arthritidis causes acute polyarthritis in rats and chronic proliferative arthritis in mice. M. arthritidis-induced arthritis serves as a model for arthritis caused by infectious agents and as a model for examining the role of the superantigen MAM (M. arthritidis T-cell mitogen) in the development of autoimmunity. M. arthritidis strain 158-1 is a spontaneous mutant of strain 158 that has a drastic reduction in virulence. We show that the mutant is missing a major antigen of 47 kDa (P47) and has acquired a protein of 67 kDa (P67). P47 and P67 partitioned into the detergent phase by extraction with Triton X-114. Coomassie blue staining of sodium dodecyl sulfate-polyacrylamide gels show that P67 is produced in abundance. Analysis of gel-purified P67 by mass spectrometry led to its identification as a lipoprotein (the open reading frame [ORF] 619 gene product) predicted from the genome sequence of M. arthritidis. PCR analysis of genomic DNA from 158 and 158-1 indicates that P47 and P67 are encoded by the same ORF 619 gene and differ only in the number of repeats in a tandem repeat region. By two-dimensional polyacrylamide gel analysis, no protein differences were detectable between 158 and 158-1 other than P47 and P67. Collectively, the data suggest that the tandem repeat region of P47 and P67 influences disease outcome.
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848
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Sun T, Chan MLH, Quek CH, Yu H. Improving mechanical stability and density distribution of hepatocyte microcapsules by fibrin clot and gold nano-particles. J Biotechnol 2005; 111:169-77. [PMID: 15219403 DOI: 10.1016/j.jbiotec.2004.02.018] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2003] [Revised: 01/19/2004] [Accepted: 02/12/2004] [Indexed: 11/21/2022]
Abstract
Bio-artificial livers (BAL) with microencapsulated hepatocytes have the typical limitations in maintaining hepatocyte functions, mechanical stability and uniform perfusion in packed or fluidized-bed bioreactors. We have previously developed microcapsules with enhanced hepatocyte functions. Here we have introduced a fibrin network inside microcapsules by (1) mixing collagen and fibrinogen with the encapsulated hepatocytes to support the cells; (2) submerging the microcapsules into a thrombin solution to induce the formation of an insoluble fibrin network inside the microcapsules. Fracture analysis on the microcapsules revealed significant improvement in mechanical stability. We have also introduced different amounts of gold nano-particles into microcapsules to achieve different densities for uniform bioreactor perfusion. These gold nano-particles also improved the mechanical stability of the microcapsules. Both the fibrin network and gold nano-particles exhibited the additional benefits of enhancing certain bio-functions of the encapsulated hepatocytes. The applications of these improved microcapsules in the development of bio-artificial livers are discussed.
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849
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Mak KCY, Yu H, Choi MC, Shen X, Lam MHW, Martin M, Wu RSS, Wong PS, Richardson BJ, Lam PKS. Okadaic acid, a causative toxin of diarrhetic shellfish poisoning, in green-lipped mussels Perna viridis from Hong Kong fish culture zones: method development and monitoring. MARINE POLLUTION BULLETIN 2005; 51:1010-7. [PMID: 16040057 DOI: 10.1016/j.marpolbul.2005.06.037] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Green-lipped mussels (Perna viridis) were collected from seven fish culture zones (FCZs) in Hong Kong and analyzed for okadaic acid (OA). A conventional HPLC method was modified by incorporating a proteinase K digestion step. Results suggest that a higher recovery (2.5 times higher) of OA was obtained from spiked samples after the addition of 1.08 mg proteinase K in comparison with samples incubated without the proteolytic enzyme. For the hepatopancreas (HP) of individual field-collected mussels, the additional digestion step can enhance OA extraction by 3.1 times. Spatial and temporal variations in OA concentrations in the mussels from various FCZs were investigated. The highest concentration of OA in mussel HP samples was 1164.9 ng/g HP wet wt. With respect to OA concentrations in whole mussel tissues from seven sites and four seasonal samplings, the concentrations were between 70.0 and 131.0 ng/g wet wt., which did not exceed the generally recognized international regulatory criteria (>200 ng/g) for OA.
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Woraratanadharm J, Rubinchik S, Yu H, Fan F, Morrow SM, Dong JY. Highly specific transgene expression mediated by a complex adenovirus vector incorporating a prostate-specific amplification feedback loop. Gene Ther 2004; 11:1399-407. [PMID: 15229631 PMCID: PMC1831545 DOI: 10.1038/sj.gt.3302307] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Development of novel therapeutic agents is needed to address the problems of locally recurrent, metastatic, and advanced hormone-refractory prostate cancer. We have constructed a novel complex adenovirus (Ad) vector regulation system that incorporates both the prostate-specific ARR2PB promoter and a positive feedback loop using the TRE promoter to enhance gene expression. This regulation strategy involves the incorporation of the TRE upstream of the prostate-specific ARR2PB promoter to enhance its activity with Tet regulation. The expressions of both GFP and tTA were placed under the control of these TRE-ARR2PB promoters, so that in the cells of prostate origin a positive feedback loop would be generated. This design greatly enhanced GFP reporter expression in prostate cancer cells, while retaining tight control of expression in nonprostate cancer cells, even at an MOI as high as 1000. This novel positive feedback loop with prostate specificity (PFLPS) regulation system we have developed may have broad applications for expressing not only high levels of toxic proteins in cancer cells, but alternatively could also be manipulated to regulate essential genes in a highly efficient conditionally replicative adenovirus vector specifically directed to prostate cancer cells. The PFLPS regulation system, therefore, serves as a promising new approach in the development of both a specific and effective vector for cancer gene therapy.
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