51
|
|
52
|
Phillips MS, Lawrence R, Sachidanandam R, Morris AP, Balding DJ, Donaldson MA, Studebaker JF, Ankener WM, Alfisi SV, Kuo FS, Camisa AL, Pazorov V, Scott KE, Carey BJ, Faith J, Katari G, Bhatti HA, Cyr JM, Derohannessian V, Elosua C, Forman AM, Grecco NM, Hock CR, Kuebler JM, Lathrop JA, Mockler MA, Nachtman EP, Restine SL, Varde SA, Hozza MJ, Gelfand CA, Broxholme J, Abecasis GR, Boyce-Jacino MT, Cardon LR. Chromosome-wide distribution of haplotype blocks and the role of recombination hot spots. Nat Genet 2003; 33:382-7. [PMID: 12590262 DOI: 10.1038/ng1100] [Citation(s) in RCA: 217] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2002] [Accepted: 01/16/2003] [Indexed: 01/30/2023]
Abstract
Recent studies of human populations suggest that the genome consists of chromosome segments that are ancestrally conserved ('haplotype blocks'; refs. 1-3) and have discrete boundaries defined by recombination hot spots. Using publicly available genetic markers, we have constructed a first-generation haplotype map of chromosome 19. As expected for this marker density, approximately one-third of the chromosome is encompassed within haplotype blocks. Evolutionary modeling of the data indicates that recombination hot spots are not required to explain most of the observed blocks, providing that marker ascertainment and the observed marker spacing are considered. In contrast, several long blocks are inconsistent with our evolutionary models, and different mechanisms could explain their origins.
Collapse
|
53
|
Silberstein P, Lawrence R, Pryor D, Shnier R. A case of neurosyphilis with a florid Jarisch-Herxheimer reaction. J Clin Neurosci 2002; 9:689-90. [PMID: 12604286 DOI: 10.1054/jocn.2002.1129] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
A 37 year old man with a 2 year history of progressive cognitive decline, unilateral tinnitus and deafness presented with complex partial seizures and a fever. On examination there was a sluggish right pupillary response but no other abnormal findings. Serum and CSF syphilis serology were both strongly positive. High dose intravenous penicillin therapy was complicated by a severe Jarisch-Herxheimer reaction (JHR) characterised by fever, obtundation, fluctuating upper motor neuron signs and complex visual and auditory hallucinations. These symptoms resolved over three days and the course of penicillin was completed. At discharge the patient's cognitive functioning was unchanged from the pretreatment state. He made gradual improvement over the following months but remains unable to live alone or work. Clinical, pathologic and radiologic findings of neurosyphilis are reviewed, as is the JHR, a self-limiting, systemic febrile response related to massive cytokine release that can occur in response to treatment of a number of bacterial infections. The similarities in pathophysiology of the JHR and the Septic Shock Syndrome are discussed, with particular reference to use of the JHR as a potential model for therapeutic agents in the treatment of septic shock.
Collapse
|
54
|
Lawrence R. People. Drug Discov Today 2002. [DOI: 10.1016/s1359-6446(02)02426-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
|
55
|
Baldwin D, Loeblich V, Lawrence R. Acidic Composition of Oleoresins and Rosins. ACTA ACUST UNITED AC 2002. [DOI: 10.1021/i460004a036] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
56
|
Fenner M, Hanley ME, Lawrence R. Comparison of seedling and adult palatability in annual and perennial plants. Funct Ecol 2002. [DOI: 10.1046/j.1365-2435.1999.00346.x] [Citation(s) in RCA: 104] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
|
57
|
Zhang L, Beeler DL, Lawrence R, Lech M, Liu J, Davis JC, Shriver Z, Sasisekharan R, Rosenberg RD. 6-O-sulfotransferase-1 represents a critical enzyme in the anticoagulant heparan sulfate biosynthetic pathway. J Biol Chem 2001; 276:42311-21. [PMID: 11551899 DOI: 10.1074/jbc.m101441200] [Citation(s) in RCA: 67] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Using recombinant retroviral transduction, we have introduced the heparin/heparan sulfate (HS) 3-O-sulfotransferase 1 (3-OST-1) gene into Chinese hamster ovary (CHO) cells. Expression of 3-OST-1 confers upon CHO cells the ability to produce anticoagulantly active HS (HS(act)). To understand how 6-OST and other proteins regulate HS(act) biosynthesis, a CHO cell clone with three copies of 3-OST-1 was chemically mutagenized. Resulting mutants that make HS but are defective in generating HS(act) were single-cell-cloned. One cell mutant makes fewer 6-O-sulfated residues. Modification of HS chains from the mutant with pure 6-OST-1 and 3'-phosphoadenosine 5'-phosphosulfate increased HS(act) from 7% to 51%. Transfection of this mutant with 6-OST-1 created a CHO cell line that makes HS, 50% of which is HS(act). We discovered in this study that (i) 6-OST-1 is a limiting enzyme in the HS(act) biosynthetic pathway in vivo when the limiting nature of 3-OST-1 is removed; (ii) HS chains from the mutant cells serve as an excellent substrate for demonstrating that 6-OST-1 is the limiting factor for HS(act) generation in vitro; (iii) in contradiction to the literature, 6-OST-1 can add 6-O-sulfate to GlcNAc residues, especially the critical 6-O-sulfate in the antithrombin binding motif; (iv) both 3-O- and 6-O-sulfation can be the final step in HS(act) biosynthesis in contrast to prior publications that concluded 3-O-sulfation is the final step in HS(act) biosynthesis; (v), in the presence of HS interacting protein peptide, 3-O-sulfate-containing sugars can be degraded into disaccharides by heparitinase digestion as demonstrated by capillary high performance liquid chromatography coupled with mass spectrometry.
Collapse
|
58
|
Walley AJ, Chavanas S, Moffatt MF, Esnouf RM, Ubhi B, Lawrence R, Wong K, Abecasis GR, Jones EY, Harper JI, Hovnanian A, Cookson WO. Gene polymorphism in Netherton and common atopic disease. Nat Genet 2001; 29:175-8. [PMID: 11544479 DOI: 10.1038/ng728] [Citation(s) in RCA: 306] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Atopic dermatitis (AD) and asthma are characterized by IgE-mediated atopic (allergic) responses to common proteins (allergens), many of which are proteinases. Loci influencing atopy have been localized to a number of chromosomal regions, including the chromosome 5q31 cytokine cluster. Netherton disease is a rare recessive skin disorder in which atopy is a universal accompaniment. The gene underlying Netherton disease (SPINK5) encodes a 15-domain serine proteinase inhibitor (LEKTI) which is expressed in epithelial and mucosal surfaces and in the thymus. We have identified six coding polymorphisms in SPINK5 (Table 1) and found that a Glu420-->Lys variant shows significant association with atopy and AD in two independent panels of families. Our results implicate a previously unrecognized pathway for the development of common allergic illnesses.
Collapse
|
59
|
Zhang L, Lawrence R, Schwartz JJ, Bai X, Wei G, Esko JD, Rosenberg RD. The effect of precursor structures on the action of glucosaminyl 3-O-sulfotransferase-1 and the biosynthesis of anticoagulant heparan sulfate. J Biol Chem 2001; 276:28806-13. [PMID: 11375390 DOI: 10.1074/jbc.m100204200] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
To understand how 2-O-sulfation of uronic acid residues influences the biosynthesis of anticoagulant heparan sulfate, the cDNA encoding glucosaminyl 3-O-sulfotransferase-1 (3-OST-1) was introduced into wild-type Chinese hamster ovary cells and mutant pgsF-17 cells, which are defective in 2-O-sulfation. 3-OST-1-transduced cells gained the ability to bind to antithrombin. Structural analysis of the heparan sulfate chains showed that 3-OST-1 generates sequences containing GlcUA-GlcN(SO(3))3(SO(3)) and GlcUA-GlcN(SO(3))3(SO(3))6(SO(3)) in both wild-type and mutant cells. In addition, IdoUA-GlcN(SO(3))3(SO(3)) and IdoUA-GlcN(SO(3))3(SO(3))6(SO(3)) accumulate in the mutant chain. These disaccharides were also observed by tagging [6-(3)H]GlcN-labeled pgsF-17 heparan sulfate in vitro with [(35)S]PAPs and purified 3-OST-1. Heparan sulfate derived from the transduced mutant also had approximately 2-fold higher affinity for antithrombin than heparan sulfate derived from the transduced wild-type cells, and it inactivated factor Xa more efficiently. This study demonstrates for the first time that (i) 3-O-sulfation by 3-OST-1 can occur independently of the 2-O-sulfation of uronic acids, (ii) 2-O-sulfation usually occurs before 3-O-sulfation, (iii) 2-O-sulfation blocks the action of 3-OST-1 at glucosamine residues located to the reducing side of IdoUA units, and (iv) that alternative antithrombin-binding structures can be made in the absence of 2-O-sulfation.
Collapse
|
60
|
Lawrence R. People. Drug Discov Today 2001. [DOI: 10.1016/s1359-6446(01)01799-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
61
|
Hammond LA, Davidson K, Lawrence R, Camden JB, Von Hoff DD, Weitman S, Izbicka E. Exploring the mechanisms of action of FB642 at the cellular level. J Cancer Res Clin Oncol 2001; 127:301-13. [PMID: 11355145 DOI: 10.1007/s004320000212] [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: 10/27/2022]
Abstract
FB642(methyl-2-benzimidazolecarbamate, carbendazim) is a systemic fungicide belonging to the benzimidazole family with antitumor activity against a broad spectrum of tumors both in vitro and in vivo such as pancreas, prostate, colon, and breast. Although the preclinical antitumor activity of FB642 has been well explored, its mechanism of action has not been as well delineated. Previous studies indicate that FB642 may interfere with mitosis and thus may disrupt or inhibit microtubule function resulting in apoptosis. This study seeks to determine if FB642 is a sufficiently novel agent worthy of further development by examining the effect of FB642 on apoptosis, the cell cycle, p53-positive and -negative tumors, and drug-resistant and MDR cell lines. The results of this present study indicate that FB642 increases the degree of apoptosis in all examined tumor cell lines, may induce G2/M uncoupling, may selectively kill p53 abnormal cells, and exhibits antitumor activity in drug- and multidrug-resistant cell lines. The induction of apoptosis by FB642, particularly in p53-deficient cells, its impressive in vivo activity against a broad spectrum of murine and human tumors, as well as an acceptable toxicity profile in animals, make FB642 an excellent candidate for further evaluation in clinical trials in cancer patients.
Collapse
|
62
|
Lawrence R. Biocomputing: impact of the genomic revolution. Drug Discov Today 2001; 6:403-405. [PMID: 11301284 DOI: 10.1016/s1359-6446(01)01737-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
|
63
|
Cookson WO, Ubhi B, Lawrence R, Abecasis GR, Walley AJ, Cox HE, Coleman R, Leaves NI, Trembath RC, Moffatt MF, Harper JI. Genetic linkage of childhood atopic dermatitis to psoriasis susceptibility loci. Nat Genet 2001; 27:372-3. [PMID: 11279517 DOI: 10.1038/86867] [Citation(s) in RCA: 273] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
We have carried out a genome screen for atopic dermatitis (AD) and have identified linkage to AD on chromosomes 1q21, 17q25 and 20p. These regions correspond closely with known psoriasis loci, as does a previously identified AD locus on chromosome 3q21. The results indicate that AD is influenced by genes with general effects on dermal inflammation and immunity.
Collapse
|
64
|
Lawrence R. Dendritic vaccine promising for gliomas. Drug Discov Today 2001; 6:329-330. [PMID: 11267912 DOI: 10.1016/s1359-6446(01)01746-9] [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]
|
65
|
Lawrence R, Martin D. Moulds, moisture and microbial contamination of First Nations housing in British Columbia, Canada. Int J Circumpolar Health 2001; 60:150-6. [PMID: 11507964 PMCID: PMC11134070] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2023] Open
Abstract
This paper reviews the difficulties experienced with mould growth in First Nations homes in British Columbia and to describe the team approach used in dealing with this problem. Humid, damp conditions promote the growth of bacteria, moulds, and dust mites. These organisms contribute to poor air quality and causes serious health problems. There is increasing evidence indicating an association between mould, particularly toxigenic moulds, and some diseases, notably asthma. These health problems usually improve when families are relocated to more suitable accommodation. Those particularly at risk include atopic, immunocompromised, very young and elderly individuals and those with chronic health conditions. Our experience suggests that substandard housing is a major contributor to poor health in First Nations communities.
Collapse
|
66
|
Lawrence R. Initial analyses of the human genome: does it reveal anything new? Drug Discov Today 2001; 6:221-222. [PMID: 11182585 DOI: 10.1016/s1359-6446(01)01715-9] [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]
|
67
|
|
68
|
Lawrence R. People. Drug Discov Today 2001. [DOI: 10.1016/s1359-6446(00)01670-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
|
69
|
Lawrence R. Craig Venter discusses life after the Human Genome Project. Interviewed by Rebecca Lawrence. Drug Discov Today 2001; 6:10-12. [PMID: 11165164 DOI: 10.1016/s1359-6446(00)01630-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
70
|
Lawrence R. What the industry says. Drug Discov Today 2001; 6:5. [PMID: 11165160 DOI: 10.1016/s1359-6446(00)01629-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
71
|
Remington G, Shammi CM, Sethna R, Lawrence R. Antipsychotic dosing patterns for schizophrenia in three treatment settings. Psychiatr Serv 2001; 52:96-8. [PMID: 11141536 DOI: 10.1176/appi.ps.52.1.96] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Daily dosages of antipsychotic medications were evaluated to determine whether current guidelines advocating lower dosing are being followed. A chart review of 163 outpatients with schizophrenia was undertaken in three outpatient hospital settings-a general community hospital, a provincial hospital, and an academic teaching hospital. The daily dosage in chlorpromazine equivalents was significantly higher in the provincial hospital (773.8 mg) than in the community hospital (355 mg) or the academic hospital (424.8 mg). A greater proportion of patients at the provincial hospital received conventional antipsychotics than novel antipsychotics or depot antipsychotics, and a greater proportion received more than one antipsychotic.
Collapse
|
72
|
Lawrence R. David Bentley discusses life after the Human Genome Project. Interviewed by Rebecca Lawrence. Drug Discov Today 2001; 6:13-14. [PMID: 11165165 DOI: 10.1016/s1359-6446(00)01631-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
73
|
Schiff R, Reddy P, Ahotupa M, Coronado-Heinsohn E, Grim M, Hilsenbeck SG, Lawrence R, Deneke S, Herrera R, Chamness GC, Fuqua SA, Brown PH, Osborne CK. Oxidative stress and AP-1 activity in tamoxifen-resistant breast tumors in vivo. J Natl Cancer Inst 2000; 92:1926-34. [PMID: 11106684 DOI: 10.1093/jnci/92.23.1926] [Citation(s) in RCA: 144] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Most breast cancers, even those that are initially responsive to tamoxifen, ultimately become resistant. The molecular basis for this resistance, which in some patients is thought to involve stimulation of tumor growth by tamoxifen, is unclear. Tamoxifen induces cellular oxidative stress, and because changes in cell redox state can activate signaling pathways leading to the activation of activating protein-1 (AP-1), we investigated whether tamoxifen-resistant growth in vivo is associated with oxidative stress and/or activation of AP-1 in a xenograft model system where resistance is caused by tamoxifen-stimulated growth. METHODS Control estrogen-treated, tamoxifen-sensitive, and tamoxifen-resistant MCF-7 xenograft tumors were assessed for oxidative stress by measuring levels of antioxidant enzyme (e.g., superoxide dismutase [SOD], glutathione S-transferase [GST], and hexose monophosphate shunt [HMS]) activity, glutathione, and lipid peroxidation. AP-1 protein levels, phosphorylated c-jun levels, and phosphorylated Jun NH(2)-terminal kinase (JNK) levels were examined by western blot analyses, and AP-1 DNA-binding and transcriptional activities were assessed by electrophoretic mobility shift assays and a reporter gene system. All statistical tests are two-sided. RESULTS Compared with control estrogen-treated tumors, tamoxifen resistant tumors had statistically significantly increased SOD (more than threefold; P=.004) and GST (twofold; P=.004) activity and statistically significantly reduced glutathione levels (greater than twofold; P<.001) and HMS activity (10-fold; P<.001). Lipid peroxides were not significantly different between control and tamoxifen-resistant tumors. We observed no differences in AP-1 protein components or DNA-binding activity. However, AP-1-dependent transcription (P=.04) and phosphorylated c-Jun and JNK levels (P<.001) were statistically significantly increased in the tamoxifen-resistant tumors. CONCLUSION Our results suggest that the conversion of breast tumors to a tamoxifen-resistant phenotype is associated with oxidative stress and the subsequent antioxidant response and with increased phosphorylated JNK and c-Jun levels and AP-1 activity, which together could contribute to tumor growth.
Collapse
|
74
|
|
75
|
Soda H, Raymond E, Sharma S, Lawrence R, Davidson K, Oka M, Kohno S, Izbicka E, Von Hoff DD. Effects of androgens on telomerase activity in normal and malignant prostate cells in vitro. Prostate 2000; 43:161-8. [PMID: 10797490 DOI: 10.1002/(sici)1097-0045(20000515)43:3<161::aid-pros1>3.0.co;2-o] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND Recent studies have shown that sex hormones regulate telomerase activity in endometrium and breast tissues. The present study was designed to clarify the effects of androgen on telomerase activity in normal and malignant prostate cells. METHODS Androgen-sensitive (LNCaP) and -independent (TSU-Pr1 and DU145) prostate cancer cell lines and normal prostate cells including basal cells were cultured in the presence or absence of 5alpha-dihydrotestosterone (DHT). RESULTS Prostate cancer cell lines exhibited high telomerase activity, and normal prostate cells showed low activity. Short or prolonged androgen-deprivation reduced telomerase activity in LNCaP cells, and DHT induced telomerase activity at the G(1) phase of the cell cycle. DHT did not modulate telomerase activity in TSU-Pr1, DU145, and normal cells. CONCLUSIONS LNCaP cells had an androgen-dependent pathway to activate telomerase, whereas TSU-Pr1 and DU145 cells as well as normal prostate cells had an androgen-independent pathway. These findings suggest that the regulatory mechanism of telomerase varies during the progression of prostate cancers.
Collapse
|