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Terry G, Londesborough P, Ho L. The construction of defective interfering rubella virus particles. Arch Virol 2000; 145:625-33. [PMID: 10795527 DOI: 10.1007/s007050050051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Two defective viral vectors containing nucleic acid sequences from rubella virus strains RJ and RS linked to the reporter gene luciferase have been constructed. The vector RNAs are shown to replicate and interfere with wildtype virus in co-infected cells. The interference is associated with a polymorphic nucleotide at nt34 in the 5' stem-loop. The use of these constructs as expression vectors is discussed.
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Cuzick J, Terry G, Ho L, Monaghan J, Lopes A, Clarkson P, Duncan I. Association between high-risk HPV types, HLA DRB1* and DQB1* alleles and cervical cancer in British women. Br J Cancer 2000; 82:1348-52. [PMID: 10755413 PMCID: PMC2374489 DOI: 10.1054/bjoc.1999.1103] [Citation(s) in RCA: 86] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Cervical scrapes from 116 British women referred with cervical cancer were tested for the presence of high oncogenic risk human papillomavirus (HPV) genotypes (HPV(hr)). Ninety-four per cent of the scrapes had one or more of these virus types and 66% were HPV16-positive. HPV18 was more frequent in adenocarcinoma. No evidence was found for an increased cancer risk associated with the HPV16 E6 350G variant. The HLA DRB1* and DQB1* alleles in these women and in 155 women with normal cytology and negative for HPV(hr) DNA were compared. DQB1*0301 alone (2P = 0.02) and in combination with DRB1*0401 (2P = 0.02) was found to be associated with cervical cancer. This was more marked in cancers positive for HPV types other than HPV16. In contrast, DRB1*1501 alone and in combination with DQB1*0602 was not significantly elevated in cancers overall, but did show some excess in HPV16-positive cancers (2P = 0.05), associated with HPV16-positive cervical cancers. Taking all cancers together, a marginally significant protective effect was found for DQB1*0501 (2P = 0.03) but no protective effect could be seen for DRB1*1301.
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Lorenzato F, Ho L, Terry G, Singer A, Santos LC, De Lucena Batista R, Lubambo T. The use of human papillomavirus typing in detection of cervical neoplasia in Recife (Brazil). Int J Gynecol Cancer 2000; 10:143-150. [PMID: 11240666 DOI: 10.1046/j.1525-1438.2000.00007.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
High risk types of human papillomavirus (HR-HPV) play a major role in cervical cancer oncogenesis. This study aims to evaluate the efficacy of HPV detection and typing as a means of identifying cervical neoplasia in a high risk population. A management algorithm for implementation of HPV detection in clinical practice is also proposed. A nested case-control within a cohort study was undertaken in Recife (Brazil). All 479 participants had cervical scrapes collected for HPV detection followed by colposcopy. Samples were blindly analyzed by polymerase chain reaction (PCR) and typed by restriction fragment length polymorphism (RFLP). HPV detection by PCR and typing with RFLP cost US$ 4.92 per woman screened in this study and is significantly better than cytology in identifying women at risk of developing cervical cancer (P = 0.0001). Women who tested positive for HR-HPV had over 35-fold increased risk of having high grade squamous intraepithelial lesion (HSIL) or cervical cancer, although this does not necessarily translate into the same risk rate for women with latent HPV infection developing major cervical neoplasia. HPV typing offers 90% sensitivity and 85% specificity for cervical cancer detection. In combination with cytology it provides a negative predictive value of 99.4% and a sensitivity of over 96% for detection of HSIL and cervical cancer. We conclude that HPV typing is an inexpensive and effective method for identification of cervical neoplasia and women at risk of developing it. It improves quality control for both false negative and false positive cytology results. Routine screening intervals could safely be increased to 3-5 years, decreasing anxiety and socio-economic inconveniences.
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Hsu AT, Ho L, Ho S, Hedman T. Joint position during anterior-posterior glide mobilization: its effect on glenohumeral abduction range of motion. Arch Phys Med Rehabil 2000; 81:210-4. [PMID: 10668777 DOI: 10.1016/s0003-9993(00)90143-6] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE To investigate the effect of joint position during an anterior-posterior glide (APG) procedure on the range of motion (ROM) of glenohumeral abduction in cadaver specimens. DESIGN Mechanical simulation of APG mobilization and abduction torque ROM measurement of the glenohumeral joint with a material testing system. The immediate mechanical efficacy of APG was compared in two groups of specimens at two different joint positions: midrange (n = 5) and end range (n = 6) of glenohumeral abduction. SETTING Biomechanics laboratory. SPECIMENS Eleven fresh cadaver shoulder specimens (mean age, 66.9+/-2.5 yrs). MAIN OUTCOME MEASURE Improvement in glenohumeral abduction torque ROM obtained before and after APG procedure. RESULTS Glenohumeral abduction improved significantly, as indicated by a significant increase (Kruskal-Wallis statistics, chi2 = 7.50, p = .006) in the torque ROM of the end range group (mean +/- standard error of the mean, 2.02 degrees +/- .20 degrees) over the midrange group (.64 degrees +/- .08 degrees). A significant difference in the magnitude of peak displacement of the humeral head between midrange (14.44+/-3.56 mm) and end range (3.19+/-.81 mm) groups was also found (Mann-Whitney test, p < .030). CONCLUSION This study demonstrated that APG technique performed at close to the end of the range of abduction is more effective in improving glenohumeral abduction ROM than that performed at the middle of the range of abduction.
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Gopal R, Janjan N, Ajani J, Ho L, Hamilton S, Cleary K, Dubrow R, Feig B, Pisters P, Lowy A, Mansfield P, Crane C. Comparison of pathologic response among three pre-operative chemoradiation regimens for resectable, locally advanced stomach cancer. Int J Radiat Oncol Biol Phys 2000. [DOI: 10.1016/s0360-3016(00)80032-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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81
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Chan EY, Mok TM, Lawton JW, Ko OK, Ho L, Lau CS. Comparison of counter immunoelectrophoresis with immunoblotting for detection of anti-extractable nuclear antigen antibodies in systemic lupus erythematosus. Asian Pac J Allergy Immunol 1999; 17:275-9. [PMID: 10698467] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
Abstract
Anti-extractable nuclear antigen (ENA) antibodies were assayed by counter immunoelectrophoresis (CIE) and immunoblotting in patients with systemic lupus erythematosus (SLE). We found the two methods showed good concordance rates, the lowest being 67% for anti-SS-A. Immunoblotting was more sensitive in detecting anti-Sm, anti-SS-B and anti-PCNA (proliferating cell nuclear antigen); CIE was more sensitive for anti-nRNP and anti-SS-A. Overall, the prevalence of these anti-ENA antibodies in SLE was increased by 9-20% if immunoblotting was used in addition to CIE. Sera specific for the 52 kDa peptide of the SS-A antigen (anti-52kDa SS-A) were better detected by immunoblotting. Anti-PCNA antibody was found in 6.3% of SLE patients and was associated with active disease and hemolytic anemia. The positive rate of anti-Sm was 9% by CIE and 23.7% by immunoblotting and this antibody was a specific marker for SLE using either method. It was concluded that using immunoblotting in addition to CIE, the overall sensitivity of detection of anti-ENA antibodies in SLE was increased and clinically useful antibodies such as anti-52kDa SS-A and anti-PCNA could be detected.
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Abstract
As a self-report questionnaire, the Cognitive Failures Questionnaire (CFQ) was originally devised to measure perception, memory, and motor lapses in daily life. CFQ scores have been found to correlate with some psychiatric symptoms associated with stress; hence, high scores on the CFQ are considered by some as an indicator of increased vulnerability to stress. Attempts to identify a stable factor structure for the CFQ have produced disparate results. However, there is a measure of agreement with regard to the presence of a "general cognitive" factor that includes loadings from most items and accounts for the lion's share of the variance. Not enough is known about the performance of the CFQ in clinical populations to use it as a measure of change. The current study sought to explore the performance of the CFQ in three groups of patients, organic (n = 209), mixed (n = 115), and functional (n = 322), and to identify correlations with measures of psychiatric morbidity (General Health Questionnaire [GHQ]), depression (Beck Depression Inventory [BDI]), and recognition memory (Signal Detection Memory Test). In the organic and functional samples, the CFQ score significantly correlated with the BDI and GHQ but not with the recognition memory measure. Three factors were found to be common to the organic and functional samples: cognitive, dissociation, and clumsiness. No characteristic pattern of CFQ item endorsement to differentiate between the organic and functional samples was found. Seven items of the CFQ performed badly because of ceiling or floor effects. The "negative" results reported herein are of relevance to researchers who may be planning to use the CFQ in clinical research. The CFQ remains a promising instrument, particularly on account of its "ecological" features, but far more investigation is needed before it is used as a standard measure in clinical practice.
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Cuzick J, Beverley E, Ho L, Terry G, Sapper H, Mielzynska I, Lorincz A, Chan WK, Krausz T, Soutter P. HPV testing in primary screening of older women. Br J Cancer 1999; 81:554-8. [PMID: 10507785 PMCID: PMC2362918 DOI: 10.1038/sj.bjc.6690730] [Citation(s) in RCA: 204] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
Certain types of the human papilloma virus (HPV) are well established as the primary cause of cervical cancer. Several studies have shown that HPV testing can improve the detection rate of high-grade cervical intraepithelial neoplasia (CIN), but these have been carried out primarily in younger women. In this study we evaluated the role of HPV testing as an adjunct to cytology in women aged 35 or over. An additional aim was to evaluate commercially available kits for HPV testing. A total of 2988 eligible women aged 34 or more attending for a routine smear in 40 general practitioner practices received HPV testing in addition to routine cytology, after having given written informed consent. Samples were assayed by polymerase chain reaction (PCR) and two versions of the Hybrid Capture test for HPV, and women were invited for colposcopy if there was any cytological abnormality (including borderline smears) or the PCR test was positive. Any apparent abnormality was biopsied and loop-excision was performed as necessary. CIN was judged by histology; 42 women had high-grade CIN, of which six were cytology negative (86% sensitivity for borderline or worse) and three had a borderline smear (79% sensitivity for mild dyskaryosis or worse). The positive predictive value of a borderline smear was only 3.1%. Eleven high-grade lesions were negative by the PCR HPV test (sensitivity 74%). The first generation Hybrid Capture II test had a similar sensitivity but an unacceptably high false positive rate (18.3%), while the newer Hybrid Capture II microtitre kit had a 95% sensitivity and a 2.3% positivity rate in normal women when used at a 2 pg ml(-1) cut-off (positive predictive value 27%). Cytology performed very well in this older cohort of women. The newer Hybrid Capture II microtitre test may be a useful adjunct, especially if the results reported here are reproducible in other studies. A combined screening test offers the possibility of greater protection and/or longer screening intervals, which could reduce the overall cost of the screening programme.
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84
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Saint CP, Ho L. A PCR test for the identification and discrimination of Legionella longbeachae serogroups 1 and 2. J Microbiol Methods 1999; 37:245-53. [PMID: 10480268 DOI: 10.1016/s0167-7012(99)00070-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
A PCR test has been developed for the specific identification of Legionella longbeachae. The test targeted sequence unique to both L. longbeachae serogroups 1 and 2 within the mip gene and permitted both species and serogroup identification. The test was trialed on a range of closely related species and 20 clinical isolates originating from Australia, the USA and Israel. Results were consistent with previous identification analyses. From 20 water samples known to contain Legionella spp. one sample yielded isolates which consistently tested positive by L. longbeachae serogroup 1 PCR. DNA sequencing of the PCR product, 5S rRNA gene sequence and hybridisation analysis with a specific oligonucleotide probe definitively identified one isolate as L. longbeachae serogroup 1. PCR testing was demonstrated as a superior method of identification to traditional seroagglutination reactions, which were ambiguous and could explain the previous failure to identify the presence of this microorganism in water.
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Kelley KA, Ho L, Winger D, Freire-Moar J, Borelli CB, Aisen PS, Pasinetti GM. Potentiation of excitotoxicity in transgenic mice overexpressing neuronal cyclooxygenase-2. THE AMERICAN JOURNAL OF PATHOLOGY 1999; 155:995-1004. [PMID: 10487857 PMCID: PMC1866889 DOI: 10.1016/s0002-9440(10)65199-1] [Citation(s) in RCA: 176] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
In this study we describe the generation of a transgenic mouse model with neuronal overexpression of the human cyclooxygenase-2, h(COX)-2, to explore its role in excitotoxicity. We report that overexpression of neuronal hCOX-2 potentiates the intensity and lethality of kainic acid excitotoxicity in coincidence with potentiation of expression of the immediate early genes c-fos and zif-268. In vitro studies extended the in vivo findings and revealed that glutamate excitotoxicity is potentiated in primary cortico-hippocampal neurons derived from hCOX-2 transgenic mice, possibly through potentiation of mitochondrial impairment. This study is the first to demonstrate a cause-effect relationship between neuronal COX-2 expression and excitotoxicity. This model system will allow the systematic examination of the role of COX-2 in mechanisms of neurodegeneration that involve excitatory amino acid pathways.
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Furlong RA, Ho L, Rubinsztein JS, Walsh C, Paykel ES, Rubinsztein DC. Analysis of the monoamine oxidase A (MAOA) gene in bipolar affective disorder by association studies, meta-analyses, and sequencing of the promoter. AMERICAN JOURNAL OF MEDICAL GENETICS 1999; 88:398-406. [PMID: 10402508] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
Abstract
Monoamine oxidases catalyse the oxidative degradation of biogenic amines including neurotransmitters such as noradrenaline, dopamine, and 5-hydroxytryptamine (5-HT). Three groups have reported positive associations of the monoamine oxidase A (MAOA) gene with bipolar affective disorder although other studies have been negative. In an extension of a previous study [Rubinsztein et al., 1996: Human Molec Genet 5:779-782] we report association studies of MAOA polymorphic markers and affective disorders. The polymorphisms comprised a CA-repeat microsatellite in intron 2 and a Fnu4HI G/T silent polymorphism at position 941 of the cDNA sequence. No significant differences were found when the control allele frequencies were compared with those in bipolar, unipolar, or combined bipolar + unipolar groups. Meta-analyses were then performed to include the data of all published studies using the MAOA microsatellite and Fnu4HI polymorphisms. Separate meta-analyses were performed for Caucasian and Japanese studies, as allele frequencies of the microsatellite in these populations were markedly different. Associations of bipolar affective disorder in pooled male and female groups were found with the MAOA microsatellite in both the Caucasian (P < 0.02) and the Japanese (P < 0.02) meta-analyses. In view of these positive associations, and as previous results have shown that coding variants do not account for the normal population variation in MAOA activity, over 1,300 bp of the promoter were sequenced in 22 bipolar cases and 1 control. A novel polymorphic promoter variable number of tandem repeats (VNTR) located approximately 1,200 bp upstream from the translation start site was demonstrated. However, there was no association of this promoter VNTR with affective disorder. These results suggest that there may be functional variants in other regions of the MAOA gene or neighbouring genes that affect bipolar affective disorder risk.
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Ho L, Pieroni C, Winger D, Purohit DP, Aisen PS, Pasinetti GM. Regional distribution of cyclooxygenase-2 in the hippocampal formation in Alzheimer's disease. J Neurosci Res 1999; 57:295-303. [PMID: 10412020 DOI: 10.1002/(sici)1097-4547(19990801)57:3<295::aid-jnr1>3.0.co;2-0] [Citation(s) in RCA: 175] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Cyclooxygenase-2 (COX-2), a key enzyme in prostanoid biosynthesis, may represent an important therapeutic target in Alzheimer's disease (AD). In the present study, we explored the regulation of COX-2 in the hippocampal formation in sporadic AD. Using semiquantitative immunocytochemical techniques, we found that in AD cases (vs. age-matched controls) neurons of the CA1-CA4 subdivisions of the hippocampal pyramidal layer showed elevation of COX-2 signal; COX-2 levels correlated with amyloid plaque density. In contrast, the level of COX-2 immunostaining in the dentate gyrus granule neurons was not elevated in AD. No expression of COX-2 in cells with glial morphology was found in any case examined. In parallel, in vitro studies found that neurons derived from transgenic mice with neuronal overexpression of COX-2 are more susceptible to beta-amyloid (Abeta) toxicity, with potentiation of redox impairment. The results indicate elevated expression of neuronal COX-2 in subregions of the hippocampal formation in AD and that such elevation may potentiate Abeta-mediated oxidative stress.
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88
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Furlong RA, Rubinsztein JS, Ho L, Walsh C, Coleman TA, Muir WJ, Paykel ES, Blackwood DH, Rubinsztein DC. Analysis and metaanalysis of two polymorphisms within the tyrosine hydroxylase gene in bipolar and unipolar affective disorders. AMERICAN JOURNAL OF MEDICAL GENETICS 1999; 88:88-94. [PMID: 10050974 DOI: 10.1002/(sici)1096-8628(19990205)88:1<88::aid-ajmg16>3.0.co;2-j] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Tyrosine hydroxylase (TH) is the rate-limiting enzyme in the synthesis of dopamine and noradrenaline. While positive associations between TH and bipolar affective disorder have been found in several studies, many studies have failed to reproduce these results. In order to clarify this situation, association studies of bipolar and unipolar affective disorder groups and metaanalyses of published data on the TH tetranucleotide repeat polymorphism were done. The association studies used the TH tetranucleotide repeat polymorphism in intron 1 and a PstI polymorphism at the 3' end of the gene. The study comprised 124 unrelated bipolar patients, 126 unipolar patients, and 242 controls. There was no significant association of either bipolar or unipolar affective disorder with the TH tetranucleotide repeat polymorphism. However, a weak association (chi2 = 3.946, 1 df, P = 0.047; odds ratio, allele 2 vs. allele 1 = 0.71 (95% CI, 0.51-0.996)) was observed in the unipolar sample with the TH-PstI polymorphism. Three metaanalyses of published data on the TH tetranucleotide repeat polymorphism in major affective disorder were performed: bipolar I + II vs. control using 583 cases and 745 controls; unipolar vs. control using 204 cases and 359 controls; and bipolar + unipolar vs. control using 846 cases and 823 controls. In each analysis there was no association of the TH tetranucleotide repeat polymorphism and affective disorder. These results do not support the tyrosine hydroxylase gene having a major role in the etiology of bipolar affective disorder. However, our data suggest that this locus should be examined in larger samples of unipolar affective disorder.
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Furlong RA, Coleman TA, Ho L, Rubinsztein JS, Walsh C, Paykel ES, Rubinsztein DC. No association of a functional polymorphism in the dopamine D2 receptor promoter region with bipolar or unipolar affective disorders. AMERICAN JOURNAL OF MEDICAL GENETICS 1998; 81:385-7. [PMID: 9754623] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The dopaminergic system, along with the serotonergic and noradrenergic systems, has been implicated in the etiology of mood disorders. An association study of a functional variant in the promoter region of the dopamine D2 receptor (DRD2) with bipolar affective disorder I or unipolar major affective disorders was performed. Variable expression of the DRD2 gene in vitro has been shown with this promoter polymorphism. One hundred and thirty-one unrelated bipolar patients, 128 unrelated unipolar patients, and 262 controls were used in the study. There were no significant differences in DRD2 allele or genotype frequencies between the affective disorder and control groups. These results do not support a major role for the DRD2 gene in the etiology of either bipolar or unipolar affective disorders.
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90
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Treich I, Ho L, Carlson M. Direct interaction between Rsc6 and Rsc8/Swh3,two proteins that are conserved in SWI/SNF-related complexes. Nucleic Acids Res 1998; 26:3739-45. [PMID: 9685490 PMCID: PMC147781 DOI: 10.1093/nar/26.16.3739] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The RSC complex of Saccharomyces cerevisiae is closely related to the SWI/SNF complex. Both complexes are involved in remodeling chromatin structure and they share conserved components. The RSC proteins Sth1, Rsc8/Swh3, Sfh1 and Rsc6 are homologs of the SWI/SNF proteins Swi2/Snf2, Swi3, Snf5 and Swp73 respectively. To investigate the RSC complex, we isolated a temperature-sensitive swh3 allele. A screen for multicopy suppressors yielded plasmids carrying the RSC6 and MAK31 loci. RSC6 also suppressed the formamide sensitivity of a strain with a C-terminal truncation of SWH3 . We show that Swh3 and Rsc6 fusion proteins interact in the two-hybrid system and that the swh3-ts mutation impairs this interaction. Finally, bacterially produced Swh3 and Rsc6 fusion proteins interact in vitro , supporting the genetic evidence for direct interaction between Swh3 and Rsc6 in vivo . We have previously shown that Swh3 also interacts with Sth1. These findings, together with the conservation of these proteins in the SWI/SNF complex and in mammalian SWI/SNF-related complexes, strongly suggest that these proteins form a structural core for the complex.
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91
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Ho L, Osaka H, Aisen PS, Pasinetti GM. Induction of cyclooxygenase (COX)-2 but not COX-1 gene expression in apoptotic cell death. J Neuroimmunol 1998; 89:142-9. [PMID: 9726836 DOI: 10.1016/s0165-5728(98)00132-5] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
In this study we assessed the regulation of cyclooxygenase (COX)-2 in models of apoptotic cell death in vivo and in vitro. By 6 h after hippocampal colchicine injection in rat, COX-2 (but not COX-1) mRNA expression was elevated. The induction of COX-2 mRNA expression preceded temporally and overlapped anatomically the cellular morphological features of apoptosis in the granule cell layer of the dentate gyrus. Similarly, in an established in vitro model of apoptosis in P19 cells, COX-2 induction preceded apoptosis in response to serum deprivation by 12 h. These studies suggest that COX-2 may be involved in the early mechanisms leading to apoptosis.
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Furlong RA, Ho L, Rubinsztein JS, Walsh C, Paykel ES, Rubinsztein DC. No association of the tryptophan hydroxylase gene with bipolar affective disorder, unipolar affective disorder, or suicidal behaviour in major affective disorder. AMERICAN JOURNAL OF MEDICAL GENETICS 1998; 81:245-7. [PMID: 9603613] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Tryptophan hydroxylase (TPH) is the rate-limiting enzyme in the synthesis of 5-hydroxytryptamine (5-HT). An association study in bipolar affective disorder I or unipolar major affective disorder was performed by using a Bfa I restriction site polymorphism within intron 7 of the tryptophan hydroxylase gene. A total of 118 bipolar, 125 unipolar, and 437 control subjects were used in the study (1:3.7 bipolar:control, 1:3.5 unipolar:control). There were no significant differences in TPH allele or genotype frequencies between the affective disorder and control groups. In addition, bipolar and/or unipolar subjects with or without a history of suicide attempts were compared for the TPH polymorphism. No significant differences were found between suicidal and non-suicidal groups in major affective disorder, in contrast to a previous study suggesting an association of this polymorphism with a history of suicide attempts among alcoholic violent offenders.
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Ho L, Williams MS, Spritz RA. A gene for autosomal dominant hypohidrotic ectodermal dysplasia (EDA3) maps to chromosome 2q11-q13. Am J Hum Genet 1998; 62:1102-6. [PMID: 9545409 PMCID: PMC1377096 DOI: 10.1086/301839] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
Autosomal dominant hypohidrotic ectodermal dysplasia (ADHED) is a disorder characterized by fine, slow-growing scalp and body hair, sparse eyebrows and eyelashes, decreased sweating, hypodontia, and nail anomalies. By genetic linkage analysis of a large ADHED kindred, we have mapped a gene for ADHED (EDA3) to the proximal long arm of chromosome 2 (q11-q13). Obligate recombinations localize EDA3 to an approximately 9-cM interval between D2S1321 and D2S308, with no apparent recombinations with markers D2S1343, D2S436, D2S293, D2S1894, D2S1784, D2S1890, D2S274, and CHLC.GAAT11C03.
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Ndisdang D, Morris PJ, Chapman C, Ho L, Singer A, Latchman DS. The HPV-activating cellular transcription factor Brn-3a is overexpressed in CIN3 cervical lesions. J Clin Invest 1998; 101:1687-92. [PMID: 9541499 PMCID: PMC508750 DOI: 10.1172/jci1089] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
The cervical cellular transcription factors Brn-3a and Brn-3b have antagonistic effects on transcription of the human papilloma virus types 16 and 18 E6 and E7 oncogenes, with Brn-3a activating expression and Brn-3b repressing it. We therefore measured expression of Brn-3a and Brn-3b mRNAs in biopsies from 16 women with no detectable cervical abnormality, and in 14 women with cervical intraepithelial neoplasia grade 3 (CIN3) lesions. Although the mean level of Brn-3b expression was similar in both groups, the mean level of Brn-3a expression was over 300-fold higher in the CIN3 samples when compared with normals. Elevated expression of Brn-3a was also detected in 16 histologically normal regions of the cervix adjacent to the CIN3 lesions, indicating that elevation of Brn-3a levels is not confined to the lesion in women with CIN3, and is thus not a consequence of the oncogenic process. The elevated levels of Brn-3a in the CIN3 patient samples, together with the activating effect of Brn-3a on HPV-16 and -18 oncogene expression, suggest that induction of this factor is involved in activating HPV-16 and -18 oncogene expression in the cervix, and hence in the production of cervical cancers induced by HPV.
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Oh J, Ho L, Ala-Mello S, Amato D, Armstrong L, Bellucci S, Carakushansky G, Ellis JP, Fong CT, Green JS, Heon E, Legius E, Levin AV, Nieuwenhuis HK, Pinckers A, Tamura N, Whiteford ML, Yamasaki H, Spritz RA. Mutation analysis of patients with Hermansky-Pudlak syndrome: a frameshift hot spot in the HPS gene and apparent locus heterogeneity. Am J Hum Genet 1998; 62:593-8. [PMID: 9497254 PMCID: PMC1376951 DOI: 10.1086/301757] [Citation(s) in RCA: 110] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
Hermansky-Pudlak syndrome (HPS) is a rare, autosomal recessive disorder in which oculocutaneous albinism, bleeding, and lysosomal ceroid storage result from defects of multiple cytoplasmic organelles-melanosomes, platelet-dense granules, and lysosomes. As reported elsewhere, we mapped the human HPS gene to chromosome segment 10q23, positionally cloned the gene, and identified three pathologic mutations of the gene, in patients from Puerto Rico, Japan, and Europe. Here, we describe mutation analysis of 44 unrelated Puerto Rican and 24 unrelated non-Puerto Rican HPS patients. A 16-bp frameshift duplication, the result of an apparent founder effect, is nearly ubiquitous among Puerto Rican patients. A frameshift at codon 322 may be the most frequent HPS mutation in Europeans. We also describe six novel HPS mutations: a 5' splice-junction mutation of IVS5, three frameshifts, a nonsense mutation, and a one-codon in-frame deletion. These mutations define an apparent frameshift hot spot at codons 321-322. Overall, however, we detected mutations in the HPS gene in only about half of non-Puerto Rican patients, and we present evidence that suggests locus heterogeneity for HPS.
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Furlong RA, Ho L, Walsh C, Rubinsztein JS, Jain S, Paykel ES, Easton DF, Rubinsztein DC. Analysis and meta-analysis of two serotonin transporter gene polymorphisms in bipolar and unipolar affective disorders. AMERICAN JOURNAL OF MEDICAL GENETICS 1998; 81:58-63. [PMID: 9514589] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The serotonin transporter is a compelling candidate gene to examine in bipolar and unipolar affective disorder, since drugs that specifically inhibit the serotonin transporter can successfully treat depression. Previous association studies of a VNTR polymorphism in intron 2 and a functional insertion/deletion polymorphism in the promoter of this gene have produced conflicting results. The present study examined allele and genotype frequencies for both of these polymorphisms and resulting haplotypes in 87 English Caucasian bipolar patients, 125 English Caucasian unipolar affective disorder patients, and 174 controls. No significant associations were detected when these unipolar or bipolar cases were compared either separately or as a pooled "affective disorder" group to the controls. A meta-analysis of over 1,400 individuals of European Caucasian origin was then performed, comprising 772 controls, 375 bipolar and 299 unipolar patients for the VNTR polymorphism, and 739 controls, 392 bipolar and 275 unipolar patients for the promoter polymorphism. A significant association of promoter allele 2 was shown with bipolar (estimated odds ratio 1.21; 95% confidence interval 1.00-1.45), unipolar (OR 1.23; 95% CI 1.01-1.42), and combined bipolar + unipolar groups (OR 1.22; 95% CI 1.04-1.42). There was no demonstrable allelic association of the VNTR polymorphism with affective disorder: for the combined bipolar + unipolar group the odds ratios for VNTR alleles 9 and 10, compared with the common allele 12 were 1.05 (95% CI 0.56-1.95) and 0.90 (95% CI 0.77-1.05). These results suggest that the promoter allele 2, which has previously been shown to result in lower levels of serotonin transporter transcription, may be associated with affective disorder risk.
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98
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Ho L, Heng JT, Lou J. Accidental ingestions in childhood. Singapore Med J 1998; 39:5-8. [PMID: 9557095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
One-hundred and twelve cases of accidental poisoning were admitted over a 2-year study period (December 1990 to December 1992). Data was collected upon admission and patients were subsequently followed-up. Fifty-four percent of admission were boys. Majority of them were toddlers between the ages of 1 and 3 years. Thirty percent of accidental ingestions occurred during the school/public holidays. These occurred when the caretakers were preoccupied. Forty-nine percent of patients ingested oral medication; 16% ingested household liquids and the rest ingested other household products like cockroach tablets and thermometer mercury. The most commonly ingested medications were paracetamol, salicylate and bronchodilators, whilst chlorox, kerosene and detergents were the common household liquids ingested. The ability of the caregivers to quantitate the ingested product was poor. The mean hospital stay of the patients was 2.5 days. The majority of them were admitted for observation which did not require antidotes. Four cases were observed in the intensive care unit. There were no fatalities during the study period. Forty-four percent of the patients had samples taken for toxicology analysis, of which, less than half had positive results. All the patients were advised on the safety measures to look out for after admission. Less than 10% of cases had prior knowledge of such measures before the accidents occurred.
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Thompson JR, Chen SW, Ho L, Langston AW, Gudas LJ. An evolutionary conserved element is essential for somite and adjacent mesenchymal expression of the Hoxa1 gene. Dev Dyn 1998; 211:97-108. [PMID: 9438427 DOI: 10.1002/(sici)1097-0177(199801)211:1<97::aid-aja9>3.0.co;2-2] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
The murine Hoxa1 gene is a member of the vertebrate Hox complex and plays a role in defining the body plan during development. At day 8.0-9.0 post coitus, Hoxa1 transcripts are detected extensively throughout the embryo in the neural tube, adjacent mesenchyme, paraxial mesoderm, somites and gut epithelium; expression extends from the most caudal region of the embryo to the rhombomere 3/4 border. This spatiotemporal expression of Hoxa1 mRNA is critical for normal embryonic development. We have previously identified a 10 bp element, called CE2, which is located approximately 3 kilobases 3' of the Hoxa1 coding region in the RAIDR5 enhancer, and which binds to an approximately 170 kd protein in retinoic acid treated P19 embryonal carcinoma cells. CE2 elements were also identified 3' of the murine Hoxb1 gene, the chicken Hoxb1 gene and the human Hoxa1 gene. To examine the role of this CE2 element in regulating Hoxa1 expression in vivo, transgenic mice were generated which express a Hoxa1 beta-galactosidase reporter gene that contains a mutation in the CE2 element. Relative to transgenic mice bearing a wild type CE2 element, the mutant CE2 construct recapitulated rhombomeric, neural, and gut epithelium expression but failed to show beta-galactosidase expression in somites and adjacent mesenchymal tissue. Gel shift analysis showed that binding activity similar to that detected in extracts prepared from retinoic acid treated P19 cells was present in nuclear extracts prepared from day 9.0 embryos. However, an additional binding complex not detected in P19 cells was also observed. These results indicate that in transgenic animals, the evolutionary conserved CE2 element is a somite and adjacent mesenchymal enhancer of Hoxa1 expression.
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Ng I, Seow E, Lee L, Ho L. Closed head injuries in children following the use of a sarong cradle. Singapore Med J 1997; 38:517-9. [PMID: 9550917] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
INTRODUCTION Sarong cradles are unique to South-East Asian culture. Their use can lead to injuries from falls, over-enthusiastic rocking and defective equipment. We present 19 children who attended the Accident and Emergency (A&E) Department of a general hospital and who sustained injuries while in a sarong cradle. All had closed head injuries. METHODS AND MATERIALS The data was collected over a 9-month period from September 1992 to May 1993. All patients with a documented history of fall following the use of a sarong cradle, were recruited into the study. The adults accompanying the patients were interviewed with a structured questionnaire. The information was recorded by the doctor in attendance. RESULTS The ages of the 19 patients ranged from 13 days to 29 months. There were 17 Chinese, 1 Malay and 1 Indian. The types of closed head injuries included minor head injury with no external signs of injury, scalp lacerations, scalp haematomas and severe head injury with an extradural haematoma. The majority (14) were discharged from the A&E Department with head injury advice, 4 were admitted to the General Neurosurgical ward and one, to the Neurosurgical Intensive Care Unit. There were no fatalities in this group. The accidents happened while the children were either sleeping (14), playing (4) or feeding (1). CONCLUSIONS While most head injuries sustained in this manner are usually mild, there is a potential that such injuries may lead to more serious injuries. Care givers who use the sarong cradle should be aware of the dangers and exercise due care during use.
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