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Lenz G, Wright G, Dave SS, Xiao W, Powell J, Zhao H, Xu W, Tan B, Goldschmidt N, Iqbal J, Vose J, Bast M, Fu K, Weisenburger DD, Greiner TC, Armitage JO, Kyle A, May L, Gascoyne RD, Connors JM, Troen G, Holte H, Kvaloy S, Dierickx D, Verhoef G, Delabie J, Smeland EB, Jares P, Martinez A, Lopez-Guillermo A, Montserrat E, Campo E, Braziel RM, Miller TP, Rimsza LM, Cook JR, Pohlman B, Sweetenham J, Tubbs RR, Fisher RI, Hartmann E, Rosenwald A, Ott G, Muller-Hermelink HK, Wrench D, Lister TA, Jaffe ES, Wilson WH, Chan WC, Staudt LM. Stromal gene signatures in large-B-cell lymphomas. N Engl J Med 2008; 359:2313-23. [PMID: 19038878 PMCID: PMC9103713 DOI: 10.1056/nejmoa0802885] [Citation(s) in RCA: 1380] [Impact Index Per Article: 81.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
BACKGROUND The addition of rituximab to combination chemotherapy with cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP), or R-CHOP, has significantly improved the survival of patients with diffuse large-B-cell lymphoma. Whether gene-expression signatures correlate with survival after treatment of diffuse large-B-cell lymphoma is unclear. METHODS We profiled gene expression in pretreatment biopsy specimens from 181 patients with diffuse large-B-cell lymphoma who received CHOP and 233 patients with this disease who received R-CHOP. A multivariate gene-expression-based survival-predictor model derived from a training group was tested in a validation group. RESULTS A multivariate model created from three gene-expression signatures--termed "germinal-center B-cell," "stromal-1," and "stromal-2"--predicted survival both in patients who received CHOP and patients who received R-CHOP. The prognostically favorable stromal-1 signature reflected extracellular-matrix deposition and histiocytic infiltration. By contrast, the prognostically unfavorable stromal-2 signature reflected tumor blood-vessel density. CONCLUSIONS Survival after treatment of diffuse large-B-cell lymphoma is influenced by differences in immune cells, fibrosis, and angiogenesis in the tumor microenvironment.
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MESH Headings
- Antibodies, Monoclonal/administration & dosage
- Antibodies, Monoclonal, Murine-Derived
- Antineoplastic Combined Chemotherapy Protocols
- Cyclophosphamide
- Disease Progression
- Doxorubicin
- Extracellular Matrix/genetics
- Gene Expression
- Gene Expression Profiling
- Gene Expression Regulation, Neoplastic
- Genes, MHC Class II
- Germinal Center
- Humans
- Immunologic Factors/administration & dosage
- Kaplan-Meier Estimate
- Lymphoma, Large B-Cell, Diffuse/drug therapy
- Lymphoma, Large B-Cell, Diffuse/genetics
- Lymphoma, Large B-Cell, Diffuse/mortality
- Lymphoma, Large B-Cell, Diffuse/pathology
- Middle Aged
- Multivariate Analysis
- Neovascularization, Pathologic/genetics
- Prednisone
- Prognosis
- Rituximab
- Stromal Cells/metabolism
- Stromal Cells/pathology
- Vincristine
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Research Support, N.I.H., Extramural |
17 |
1380 |
2
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Abstract
Multidrug resistance (MDR), whereby tumor cells simultaneously possess intrinsic or acquired cross-resistance to diverse chemotherapeutic agents, hampers the effective treatment of cancer. Molecular investigations in MDR resulted in the isolation and characterization of genes coding for several proteins associated with MDR, including P-glycoprotein (P-gp), the multidrug resistance associated protein (MRP1), the lung resistance protein (LRP), and, more recently, the breast cancer resistance protein (BCRP). These transmembrane proteins cause MDR either by decreasing the total intracellular retention of drugs or redistributing intracellular accumulation of drugs away from target organelles. These proteins are expressed at varying degrees in different neoplasms, including the AIDS-associated non-Hodgkin lymphoma and Kaposi sarcoma and are generally associated with poor prognosis. Several MDR-reversing agents are in various stages of clinical development. First-generation modulators such as verapamil, quinidine, and cyclosporin required high doses of drugs to reverse MDR and were associated with unacceptable toxicities. Second- and third-generation MDR inhibitors include PSC 833, GF120918, VX-710, and LY335979, among others. Limitations to the use of these modulators include multiple and redundant cellular mechanisms of resistance, alterations in pharmacokinetics of cytotoxic agents, and clinical toxicities. Studies to validate the role of MDR reversal in the treatment of various malignancies are underway. A potential use of these agents may be to enhance intestinal drug absorption and increase drug penetration to biologically important protective barriers, such as the blood-brain, blood-cerebrospinal fluid, and the maternal-fetal barriers. The use of MDR modulators with drugs such as the antiviral protease inhibitors and cytotoxics may enhance drug accumulation in sanctuary sites that are traditionally impenetrable to these agents.
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MESH Headings
- ATP Binding Cassette Transporter, Subfamily B, Member 1/metabolism
- ATP Binding Cassette Transporter, Subfamily G, Member 2
- ATP-Binding Cassette Transporters/metabolism
- Antineoplastic Agents/administration & dosage
- Antineoplastic Agents/therapeutic use
- Biological Transport
- Cyclosporins/therapeutic use
- DNA-Binding Proteins/metabolism
- Drug Resistance, Multiple
- Drug Resistance, Neoplasm
- Humans
- Lymphoma, AIDS-Related/drug therapy
- Lymphoma, AIDS-Related/metabolism
- Lymphoma, Non-Hodgkin/drug therapy
- Lymphoma, Non-Hodgkin/metabolism
- Multidrug Resistance-Associated Proteins
- MutS Homolog 3 Protein
- Neoplasm Proteins/metabolism
- Prognosis
- Vault Ribonucleoprotein Particles/metabolism
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Review |
25 |
302 |
3
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Ratner L, Lee J, Tang S, Redden D, Hamzeh F, Herndier B, Scadden D, Kaplan L, Ambinder R, Levine A, Harrington W, Grochow L, Flexner C, Tan B, Straus D. Chemotherapy for human immunodeficiency virus-associated non-Hodgkin's lymphoma in combination with highly active antiretroviral therapy. J Clin Oncol 2001; 19:2171-8. [PMID: 11304769 DOI: 10.1200/jco.2001.19.8.2171] [Citation(s) in RCA: 220] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
PURPOSE This study investigated the efficacy, toxicity, and pharmacokinetic interactions resulting from simultaneous combination chemotherapy and highly active antiretroviral therapy (HAART) for patients with human immunodeficiency virus (HIV)-associated non-Hodgkin's lymphoma (NHL). In addition, the effects on viral load, CD4 counts, and opportunistic infections were examined with the use of combination chemotherapy combined with HAART. PATIENTS AND METHODS Sixty-five patients with previously untreated and measurable disease at any stage of HIV-associated NHL of intermediate or high grade were entered onto this study at 17 different centers. The first 40 patients entered onto the study received reduced doses of cyclophosphamide and doxorubicin, combined with vincristine and prednisone (modified CHOP [mCHOP]), whereas the subsequent 25 patients entered onto the study received full doses of CHOP combined with granulocyte colony-stimulating factor (G-CSF). All patients also received stavudine, lamivudine, and indinavir. RESULTS The complete response rates were 30% and 48% among patients who received mCHOP and full-dose CHOP combined with HAART, respectively. Grade 3 or 4 neutropenia occurred in 25% of patients receiving mCHOP and 12% of those receiving full-dose CHOP combined with G-CSF (25% v 12%). There were similar numbers of patients with grade 3 or 4 hyperbilirubinemia (12% and 17%), constipation and abdominal pain (18% and 17%), and transaminase elevation (48% and 52%) on the modified and full-dose arms of the study, respectively. Doxorubicin clearance and indinavir concentration curves were similar among patients on this study and historical controls, whereas cyclophosphamide clearance was 1.5-fold reduced as compared with control values. Human immunodeficiency virus (HIV) load declined from a median baseline value of 29,000 copies/mL to a median minimum value on therapy of 500 copies/mL. CONCLUSION Either modified-dose or full-dose CHOP chemotherapy for HIV-NHL, delivered with HAART, is effective and tolerable.
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Clinical Trial |
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220 |
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Crofford LJ, Tan B, McCarthy CJ, Hla T. Involvement of nuclear factor kappa B in the regulation of cyclooxygenase-2 expression by interleukin-1 in rheumatoid synoviocytes. ARTHRITIS AND RHEUMATISM 1997; 40:226-36. [PMID: 9041934 DOI: 10.1002/art.1780400207] [Citation(s) in RCA: 215] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
OBJECTIVE To evaluate involvement of the transcription factor nuclear factor kappa B (NF-kappa B) in the increased expression of cyclooxygenase-2 (COX-2) stimulated by interleukin-1 beta (IL-1 beta) in primary rheumatoid synoviocytes. METHODS We treated early-passage rheumatoid synoviocytes with IL-1 beta and examined the time course of NF-kappa B translocation to the nucleus by Western blot analysis, as well as NF-kappa B binding to the COX-2 promoter/enhancer by electrophoretic mobility shift assay. We correlated the time course of NF-kappa B binding with expression of COX-2 messenger RNA (mRNA) and protein. Synoviocytes were then treated with either sense or antisense phosphorothioate-modified oligonucleotides derived from the transcription start site of the human NF-kappa B p65 RNA. We analyzed NF-kappa B binding to the COX-2 promoter and COX-2 protein levels after these treatments. RESULTS IL-1 beta rapidly stimulated the translocation of the p65, p50, and c-rel NF-kappa B subunits from the cytoplasm to the nucleus. Electrophoretic mobility shift assay demonstrated binding to 2 NF-kappa B sites within the COX-2 promoter/enhancer, with a time course identical to that of nuclear localization of NF-kappa B. Supershift analysis revealed that binding activity was due primarily to the p65-p50 heterodimer and the p50 homodimer. With appropriate lag time after NF-kappa B binding, COX-2 mRNA and protein were increased. Pretreatment of RA synoviocytes with NF-kappa B p65 antisense oligonucleotides resulted in decreased binding to the COX-2 promoter and decreased COX-2 protein expression. CONCLUSION These data demonstrate that signaling via the NF-kappa B pathway is involved in regulation of COX-2 expression induced by IL-1 beta in RA synoviocytes.
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28 |
215 |
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Tan BH, Fu J, Sugrue RJ, Yap EH, Chan YC, Tan YH. Recombinant dengue type 1 virus NS5 protein expressed in Escherichia coli exhibits RNA-dependent RNA polymerase activity. Virology 1996; 216:317-25. [PMID: 8607261 DOI: 10.1006/viro.1996.0067] [Citation(s) in RCA: 200] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The complete nonstructural NS5 gene of dengue type 1 virus, Singapore strain S275/90 (D1-S275/90) was expressed in Escherichia coli as a glutathione S-transferase (GST) fusion protein (126 kDa). The GST-NS5 fusion protein was purified and the recombinant NS5 protein released from the fusion protein by thrombin cleavage. The recombinant NS5 had a predicted molecular weight of 100 kDa and reacted with antiserum against D1-S275/90 virus in Western blot analysis. The purified recombinant NS5 protein possessed RNA-dependent RNA polymerase activity which was inhibited (>99%) by antibodies against the recombinant NS5 protein. The polymerase product was shown to be a negative-stranded RNA molecule, of template size, which forms a double-stranded complex with the template RNA.
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29 |
200 |
6
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Chen J, Tan B, Karteris E, Zervou S, Digby J, Hillhouse EW, Vatish M, Randeva HS. Secretion of adiponectin by human placenta: differential modulation of adiponectin and its receptors by cytokines. Diabetologia 2006; 49:1292-302. [PMID: 16570162 DOI: 10.1007/s00125-006-0194-7] [Citation(s) in RCA: 185] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/18/2005] [Accepted: 12/22/2005] [Indexed: 11/28/2022]
Abstract
AIMS/HYPOTHESIS Pregnancy, a state of insulin resistance, is associated with elevated levels of cytokines and profound alterations in metabolism. Serum adiponectin, an adipokine with anti-inflammatory and insulin-sensitising properties, has been shown to be lower in patients with gestational diabetes mellitus, a state of greater insulin resistance than normal pregnancies. Hypothesising that the human placenta is a source of adiponectin, we investigated its expression and secretion, and the regulation by cytokines of adiponectin and its receptors. METHODS Real-time RT-PCR, radioimmunoassay, Western blotting, radioligand binding and immunofluorescent analyses were applied to demonstrate the expression, secretion and functionality of placental adiponectin. RESULTS Adiponectin gene expression and protein were found in the human term placenta, with expression primarily in the syncytiotrophoblast. RIA of conditioned media from explant experiments revealed that the placenta can secrete adiponectin in vitro. Addition of conditioned media to HEK-293 cells transfected with the gene for adiponectin receptor-1 (ADIPOR1) altered the phosphorylation status of extracellular signal-regulated kinase 1/2 and p38 mitogen-activated protein kinase, an effect abolished after preabsorption with adiponectin antibody. Cytokines, including TNF-alpha, IFN-gamma, IL-6 and leptin, differentially modulated placental adiponectin receptors as well as adiponectin gene expression and secretion. Interestingly, in placentae from women with gestational diabetes mellitus, we observed significant downregulation of adiponectin mRNA, significant upregulation of ADIPOR1 expression, and a non-significant increase in ADIPOR2 expression. CONCLUSIONS/INTERPRETATION Our results indicate that the human placenta produces and secretes adiponectin, and that adiponectin and its receptors are differentially regulated by cytokines and their expression altered in women with gestational diabetes mellitus. Collectively, our novel data suggest that adiponectin may play a role in adapting energy metabolism at the materno-fetal interface.
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19 |
185 |
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Singaraja RR, Bocher V, James ER, Clee SM, Zhang LH, Leavitt BR, Tan B, Brooks-Wilson A, Kwok A, Bissada N, Yang YZ, Liu G, Tafuri SR, Fievet C, Wellington CL, Staels B, Hayden MR. Human ABCA1 BAC transgenic mice show increased high density lipoprotein cholesterol and ApoAI-dependent efflux stimulated by an internal promoter containing liver X receptor response elements in intron 1. J Biol Chem 2001; 276:33969-79. [PMID: 11423537 DOI: 10.1074/jbc.m102503200] [Citation(s) in RCA: 162] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
By using BAC transgenic mice, we have shown that increased human ABCA1 protein expression results in a significant increase in cholesterol efflux in different tissues and marked elevation in high density lipoprotein (HDL)-cholesterol levels associated with increases in apoAI and apoAII. Three novel ABCA1 transcripts containing three different transcription initiation sites that utilize sequences in intron 1 have been identified. In BAC transgenic mice there is an increased expression of ABCA1 protein, but the distribution of the ABCA1 product in different cells remains similar to wild type mice. An internal promoter in human intron 1 containing liver X response elements is functional in vivo and directly contributes to regulation of the human ABCA1 gene in multiple tissues and to raised HDL cholesterol, apoAI, and apoAII levels. A highly significant relationship between raised protein levels, increased efflux, and level of HDL elevation is evident. These data provide proof of the principle that increased human ABCA1 efflux activity is associated with an increase in HDL levels in vivo.
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MESH Headings
- ATP Binding Cassette Transporter 1
- ATP-Binding Cassette Transporters/genetics
- ATP-Binding Cassette Transporters/physiology
- Animals
- Apolipoprotein A-I/metabolism
- Base Sequence
- COS Cells
- Cell Line
- Cells, Cultured
- Cholesterol/metabolism
- Cholesterol, HDL/metabolism
- Cloning, Molecular
- DNA-Binding Proteins
- Humans
- Immunohistochemistry
- Introns
- Lipids/blood
- Liver/metabolism
- Liver X Receptors
- Macrophages/metabolism
- Mice
- Mice, Transgenic
- Models, Genetic
- Molecular Sequence Data
- Orphan Nuclear Receptors
- Promoter Regions, Genetic
- RNA, Messenger/metabolism
- Receptors, Cytoplasmic and Nuclear
- Receptors, Retinoic Acid/genetics
- Receptors, Thyroid Hormone/genetics
- Response Elements
- Reverse Transcriptase Polymerase Chain Reaction
- Transcriptional Activation
- Transfection
- Tumor Cells, Cultured
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24 |
162 |
8
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Radin S, Ducheyne P, Kamplain T, Tan BH. Silica sol-gel for the controlled release of antibiotics. I. Synthesis, characterization, and in vitro release. JOURNAL OF BIOMEDICAL MATERIALS RESEARCH 2001; 57:313-20. [PMID: 11484196 DOI: 10.1002/1097-4636(200111)57:2<313::aid-jbm1173>3.0.co;2-e] [Citation(s) in RCA: 138] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Room temperature processed silica sol-gel (xerogel) was investigated as a novel controlled release carrier of antibiotics (vancomycin). Xerogel characteristics, in vitro release properties, and bactericidal efficacy of the released antibiotic were determined. The xerogel/vancomycin composite showed a long-term sustained release (up to 6 weeks). In addition, bactericidal efficacy of released vancomycin was retained. The kinetics of release and the amount released were dose dependent. The initial, first-order release was followed by a near-zero-order release. The time to transition from the first- to zero-order release increased with vancomycin load (from 2 to 3 weeks with load increase from 2.2 to 11.1 mg/g). Regardless of the load, about 70% of the original vancomycin content was released by the transitional point, and the cumulative release after 6 weeks of immersion was about 90%. This study, combined with other reports documenting biocompatibility and controlled resorbability of the xerogel/drug composite in vivo, suggests that silica xerogel is a promising controlled release material for the treatment of bone infections.
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24 |
138 |
9
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Deans DAC, Tan BH, Wigmore SJ, Ross JA, de Beaux AC, Paterson-Brown S, Fearon KCH. The influence of systemic inflammation, dietary intake and stage of disease on rate of weight loss in patients with gastro-oesophageal cancer. Br J Cancer 2009; 100:63-9. [PMID: 19127266 PMCID: PMC2634686 DOI: 10.1038/sj.bjc.6604828] [Citation(s) in RCA: 131] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Revised: 11/05/2008] [Accepted: 11/21/2008] [Indexed: 02/06/2023] Open
Abstract
Although weight loss is often a dominant symptom in patients with upper gastrointestinal malignancy, there is a lack of objective evidence describing changes in nutritional status and potential associations between weight loss, food intake, markers of systemic inflammation and stage of disease in such patients. Two hundred and twenty patients diagnosed with gastric/oesophageal cancer were studied. Patients underwent nutritional assessment consisting of calculation of body mass index, measurement of weight loss, dysphagia scoring and estimation of dietary intake. Serum acute-phase protein concentrations were determined by enzyme-linked immunosorbent assay. In all, 182 (83%) patients had lost weight at diagnosis (median loss, 7% body weight). Weight loss was associated with poor performance status, advanced disease stage, dysphagia, reduced dietary intake and elevated serum C-reactive protein (CRP) concentrations. Multiple regression identified dietary intake (estimate of effect, 38%), serum CRP concentrations (estimate of effect, 34%) and stage of disease (estimate of effect, 28%) as independent variables in determining degree of weight loss. Mechanisms other than reduced dietary intake or mechanical obstruction by the tumour appear to be involved in the nutritional decline in patients with gastro-oesophageal malignancy. Recognition that systemic inflammation plays a role in nutritional depletion may inform the development of appropriate therapeutic strategies to ameliorate weight loss, making patients more tolerant of cancer-modifying treatments such as chemotherapy.
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other |
16 |
131 |
10
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Johnson EE, Hamer R, Nora RM, Tan B, Eisenstein N, Engelhart C. The Lie/Bet Questionnaire for screening pathological gamblers. Psychol Rep 1997; 80:83-8. [PMID: 9122356 DOI: 10.2466/pr0.1997.80.1.83] [Citation(s) in RCA: 128] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
A 2-item questionnaire was derived from 10 DSM-IV criteria for pathological gambling. Subjects were 362 men, 191 classified as pathological gamblers and 171 as nonproblem-gambling controls. The two items were significant in sensitivity and negative predictive value and significant in specificity and positive predictive value.
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28 |
128 |
11
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Tan BH, Chakrabarti A, Li RY, Patel AK, Watcharananan SP, Liu Z, Chindamporn A, Tan AL, Sun PL, Wu UI, Chen YC. Incidence and species distribution of candidaemia in Asia: a laboratory-based surveillance study. Clin Microbiol Infect 2015; 21:946-53. [PMID: 26100373 DOI: 10.1016/j.cmi.2015.06.010] [Citation(s) in RCA: 115] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2014] [Revised: 06/04/2015] [Accepted: 06/06/2015] [Indexed: 11/19/2022]
Abstract
The epidemiology of candidaemia varies between hospitals and geographic regions. Although there are many studies from Asia, a large-scale cross-sectional study across Asia has not been performed. We conducted a 12-month, laboratory-based surveillance of candidaemia at 25 hospitals from China, Hong Kong, India, Singapore, Taiwan and Thailand. The incidence and species distribution of candidaemia were determined. There were 1601 episodes of candidaemia among 1.2 million discharges. The overall incidence was 1.22 episodes per 1000 discharges and varied among the hospitals (range 0.16-4.53 per 1000 discharges) and countries (range 0.25-2.93 per 1000 discharges). The number of Candida blood isolates and the total number of fungal isolates were highly correlated among the six countries (R² = 0.87) and 25 hospitals (R² = 0.77). There was a moderate correlation between incidence of candidaemia and the intensive care unit (ICU)/total bed ratio (R² = 0.47), although ICUs contributed to only 23% of candidaemia cases. Of 1910 blood isolates evaluated, Candida albicans was most frequently isolated (41.3%), followed by Candida tropicalis (25.4%), Candida glabrata (13.9%) and Candida parapsilosis (12.1%). The proportion of C. tropicalis among blood isolates was higher in haemato-oncology wards than others wards (33.7% versus 24.5%, p 0.0058) and was more likely to be isolated from tropical countries than other Asian countries (46.2% versus 18.9%, p 0.04). In conclusion, the ICU settings contribute, at least in part, to the incidence variation among hospitals. The species distribution is different from Western countries. Both geographic and healthcare factors contribute to the variation of species distribution.
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Research Support, Non-U.S. Gov't |
10 |
115 |
12
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Berth-Jones J, Finlay AY, Zaki I, Tan B, Goodyear H, Lewis-Jones S, Cork MJ, Bleehen SS, Salek MS, Allen BR, Smith S, Graham-Brown RA. Cyclosporine in severe childhood atopic dermatitis: a multicenter study. J Am Acad Dermatol 1996; 34:1016-21. [PMID: 8647967 DOI: 10.1016/s0190-9622(96)90281-9] [Citation(s) in RCA: 115] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
BACKGROUND Severe atopic dermatitis (AD) remains difficult to treat. Cyclosporine is effective in adults but has not previously been investigated in children with AD. OBJECTIVE The aims were to investigate the efficacy, safety, and tolerability of cyclosporine in severe refractory childhood AD. METHODS Subjects 2 to 16 years of age were treated for 6 weeks with cyclosporine, 5 mg/kg per day, in an open study. Disease activity was monitored every 2 weeks by means of sign scores, visual analogue scales for symptoms, and quality-of-life questionnaires. Adverse events were monitored. Efficacy and tolerability were assessed with five-point scales. RESULTS Twenty-seven children were treated. Significant improvements were seen in all measures of disease activity. Twenty-two showed marked improvement or total clearing. Quality of life improved for both the children and their families. Tolerability was considered good or very good in 25 subjects. CONCLUSION Cyclosporine may offer an effective, safe, and well-tolerated short-term treatment option for children with severe AD.
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Clinical Trial |
29 |
115 |
13
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Abstract
The purpose of this study was to assess the intensity and energy cost of dance simulation in relation to the American College of Sports Medicine (ACSM) recommendations on the quantity and quality of exercise for developing and maintaining cardiorespiratory fitness, and to assess its safety. Forty subjects (21 males and 19 females, age 17.5 +/- 0.7 years) had their heart rate (HR) and oxygen consumption (.VO(2)) measured during maximal treadmill exercise and during a dance simulation game at a self-selected level of difficulty. They were monitored for injuries during and after the study. The results showed a mean HR of 137 beats x min(-1) (139 beats x min(-1) for males and 136 beats x min(-1) for females) and a mean .VO(2) of 24.6 ml x kg(-1) x min(-1) (25.3 ml x kg(-1) x min(-1) for males and 23.8 ml x kg(-1) x min(-1) for females) during the dance simulation game test, with an estimated energy expenditure of 480 W (550 W for males and 410 W for females). The dance intensity only just meets the minimum ACSM guidelines, so dancer-players will need to play for extended periods to improve or maintain cardiorespiratory fitness or to lose weight. No injuries occurred during 201 hours of dance time.
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23 |
97 |
14
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Tan B. Analysis of selected pesticides and alkylphenols in human cord blood by gas chromatograph-mass spectrometer. Talanta 2003; 61:385-91. [DOI: 10.1016/s0039-9140(03)00281-9] [Citation(s) in RCA: 96] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2002] [Revised: 04/30/2003] [Accepted: 05/05/2003] [Indexed: 11/29/2022]
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22 |
96 |
15
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Caliendo AM, St George K, Kao SY, Allega J, Tan BH, LaFontaine R, Bui L, Rinaldo CR. Comparison of quantitative cytomegalovirus (CMV) PCR in plasma and CMV antigenemia assay: clinical utility of the prototype AMPLICOR CMV MONITOR test in transplant recipients. J Clin Microbiol 2000; 38:2122-7. [PMID: 10834964 PMCID: PMC86743 DOI: 10.1128/jcm.38.6.2122-2127.2000] [Citation(s) in RCA: 89] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The correlation between the prototype AMPLICOR CMV MONITOR test (Roche Molecular Systems), a quantitative PCR assay, and the cytomegalovirus (CMV) pp65 antigenemia assay was evaluated in transplant recipients. Sequential blood specimens were collected on 29 patients (491 specimens), the leukocyte fraction was tested by CMV antigenemia, and quantitative PCR was performed on plasma specimens. None of the 15 patients (242 specimens) who were antigenemia negative were positive for CMV DNA by PCR, and none of these patients developed active CMV disease. There were 14 antigenemia-positive patients, 8 of whom developed active CMV disease. In all patients, there was a good association between the antigenemia and PCR assays. Ganciclovir-resistant virus was isolated from three patients with active CMV disease. These three patients had persistently elevated levels of antigenemia and CMV DNA by PCR when resistance to ganciclovir developed. This standardized, quantitative CMV PCR assay on plasma has clinical utility for the diagnosis of active disease and in monitoring the response to antiviral therapy in transplant recipients.
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research-article |
25 |
89 |
16
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Brozinick JT, Hawkins E, Hoang Bui H, Kuo MS, Tan B, Kievit P, Grove K. Plasma sphingolipids are biomarkers of metabolic syndrome in non-human primates maintained on a Western-style diet. Int J Obes (Lond) 2013; 37:1064-70. [PMID: 23207405 PMCID: PMC3718866 DOI: 10.1038/ijo.2012.191] [Citation(s) in RCA: 82] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/11/2012] [Revised: 10/09/2012] [Accepted: 10/16/2012] [Indexed: 12/18/2022]
Abstract
BACKGROUND The intake of a Western diet enriched in animal fat has been shown to be a major risk factor for Type 2 diabetes and obesity. Previous rodent studies have indicated that these conditions may be triggered by the accumulation of the sphingolipid ceramide in insulin-sensitive tissues. However, data are lacking in this regard from both humans and non-human primates. OBJECTIVE Here we have investigated the relationship between plasma ceramides and metabolic syndrome in Rhesus macaques fed a high-fat and high-fructose (HFFD) 'western' diet. METHODS We investigated this relationship in cohorts of monkeys fed a HFFD for a period of 8 months to 5 years. Animals were classified as control, pre-diabetic or diabetic based on fasting plasma parameters and insulin sensitivity. RESULTS HFFD treatment produced significant increases in body weight and body fat and also resulted in a decline in insulin sensitivity. In parallel to the reduction in insulin sensitivity, significant increases in both plasma ceramide and dihydroceramide levels were observed, which further increased as animals progressed to the diabetic state. Plasma levels of the rare sphingolipid C18:0 deoxysphinganine, a marker of increased metabolic flux through serine palmitoyl transferase (SPT), were also elevated in both pre- and diabetic animals. Furthermore, plasma serine levels were significantly elevated in diabetic monkeys, which may indicate a shift in SPT substrate selectivity from serine to alanine or glycine. In contrast, branch chain amino acids were unchanged in pre-diabetic non-human primates, and only plasma valine levels were elevated in diabetic animals. CONCLUSION Together, these data indicate that HFFD induces de novo synthesis of ceramides in non-human primates, and that increased production of plasma ceramides is significantly correlated with the decline in insulin sensitivity.
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Research Support, N.I.H., Extramural |
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Fu J, Tan BH, Yap EH, Chan YC, Tan YH. Full-length cDNA sequence of dengue type 1 virus (Singapore strain S275/90). Virology 1992; 188:953-8. [PMID: 1585663 DOI: 10.1016/0042-6822(92)90560-c] [Citation(s) in RCA: 79] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The complete nucleotide sequence and the deduced amino acid sequence of the genome of dengue virus type 1 (Singapore strain S275/90) were determined from cDNA clones. The single-stranded, positive-sense RNA is 10,718 nucleotides in length and contains a single long open reading frame of 10,188 nucleotides encoding a polyprotein of 3396 amino acids. The genomic size and organization were found to be similar to that of other dengue virus serotypes. Both the nucleotide and deduced amino acid sequences were compared with the partial sequence of DEN1 (Nauru Island) and complete sequences of DNE2 (Jamaica), DEN3 (H87), and DEN4 (Dominica) virus genomes.
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Comparative Study |
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Hosen N, Shirakata T, Nishida S, Yanagihara M, Tsuboi A, Kawakami M, Oji Y, Oka Y, Okabe M, Tan B, Sugiyama H, Weissman IL. The Wilms’ tumor gene WT1-GFP knock-in mouse reveals the dynamic regulation of WT1 expression in normal and leukemic hematopoiesis. Leukemia 2007; 21:1783-91. [PMID: 17525726 DOI: 10.1038/sj.leu.2404752] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The Wilms' tumor gene WT1 is overexpressed in most of human leukemias regardless of disease subtypes. To characterize the expression pattern of WT1 during normal and neoplastic hematopoiesis, we generated a knock-in reporter green fluorescent protein (GFP) mouse (WT1(GFP/+)) and assayed for WT1 expression in normal and leukemic hematopoietic cells. In normal hematopoietic cells, WT1 was expressed in none of the long-term (LT) hematopoietic stem cells (HSC) and very few (<1%) of the multipotent progenitor cells. In contrast, in murine leukemias induced by acute myeloid leukemia 1 (AML1)/ETO+TEL/PDGFbetaR or BCR/ABL, WT1 was expressed in 40.5 or 38.9% of immature c-kit(+)lin(-)Sca-1(+) (KLS) cells, which contained a subset, but not all, of transplantable leukemic stem cells (LSCs). WT1 expression was minimal in normal fetal liver HSCs and mobilized HSCs, both of which are stimulated for proliferation. In addition, overexpression of WT1 in HSCs did not result in proliferation or expansion of HSCs and their progeny in vivo. Thus, the mechanism by which expansion of WT1-expressing cells occurs in leukemia remains unclear. Nevertheless, our results demonstrate that the WT1(GFP/+) mouse is a powerful tool for analyzing WT1-expressing cells, and they highlight the potential of WT1, as a specific therapeutic target that is expressed in LSCs but not in normal HSCs.
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MESH Headings
- Animals
- Bone Marrow
- Cell Proliferation
- Colony-Forming Units Assay
- Disease Models, Animal
- Female
- Gene Expression Regulation, Neoplastic
- Genes, Wilms Tumor
- Green Fluorescent Proteins/genetics
- Green Fluorescent Proteins/metabolism
- Hematopoiesis
- Hematopoietic Stem Cells/cytology
- Hematopoietic Stem Cells/metabolism
- Hematopoietic Stem Cells/pathology
- Humans
- Immunophenotyping
- Lentivirus
- Leukemia, Experimental/genetics
- Leukemia, Experimental/metabolism
- Leukemia, Experimental/pathology
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/genetics
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/metabolism
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/pathology
- Male
- Mice
- Mice, Inbred C57BL
- Neoplastic Stem Cells/pathology
- Transfection
- WT1 Proteins/genetics
- WT1 Proteins/physiology
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Hussain H, Tan BH, Seah GL, Liu Y, He CB, Davis TP. Micelle formation and gelation of (PEG-P(MA-POSS)) amphiphilic block copolymers via associative hydrophobic effects. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2010; 26:11763-11773. [PMID: 20536258 DOI: 10.1021/la101686q] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
A series of well-defined amphiphilic di- and triblock copolymers have been synthesized, using atom transfer radical polymerization, with poly(ethylene glycol) (PEG) and poly(methacrylisobutyl polyhedral oligomeric silsesquioxane) P(MA-POSS) as the hydrophilic and hydrophobic blocks, respectively. The detailed self-assembly behavior of the amphiphilic macromolecules in aqueous media was studied using both static and dynamic light scattering (SLS and DLS) techniques. The evolution of block copolymer micelle formation in THF/water mixture (20/80 v/v) was monitored as the THF evaporated from the solvent mixture. Initially the block copolymer chains existed as unimers in solution, followed by the formation of smaller aggregates (R(h) < 2 nm) after 30 min, eventually growing in size to reach an equilibrium size when all the THF evaporated within 24 h. The micelles formed by the block copolymers were found to be kinetically unstable (not frozen); i.e., they tended to revert to individual copolymer chains on dilution. The hydrodynamic radii, R(h), of the micelles varied with the degree of polymerization (DP) of the hydrophobic P(MA-POSS); for example, for PEG(5K)-b-P(MA-POSS), an increase from R(h) approximately 13.3 +/- 1.1 nm to R(h) approximately 17.5 +/- 1.4 nm was observed with a nominal change in the DP of P(MA-POSS) from 4 to 6. The micelles formed by the triblock copolymers (P(MA-POSS)-b-PEG(10K)-b-P(MA-POSS)) were comparable in size to the diblock copolymer micelles; e.g., R(h) approximately 14.0 +/- 1.3 nm was found for P(MA-POSS)(4)-b-PEG(10K)-b-P(MA-POSS)(4). The micellar structures created by the triblocks in aqueous media were "flowerlike", where the PEG middle block adopted a loop conformation in the micelle corona. In addition to micelles, larger aggregates formed by P(MA-POSS)-b-PEG(10K)-b-P(MA-POSS) were also detected in solution. The larger aggregates may suggest a contribution from some PEG blocks adopting an extended conformation with one end dangling in solution, causing gelation at higher copolymer concentrations via intermicellar interactions. The P(MA-POSS)(4)-b-PEG(10K)-b- P(MA-POSS)(4) formed a gel in water at approximately 8.8 wt % copolymer concentration. No gel formation by diblock copolymers was observed; however, the addition of a small amount of triblock copolymer to an aqueous solution of diblock copolymer results in gel formation. Finally, rheological behavior of the obtained gels was also investigated.
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Tan SH, Tan BH, Goh CL, Tan KC, Tan MF, Ng WC, Tan WC. Detection of Mycobacterium tuberculosis DNA using polymerase chain reaction in cutaneous tuberculosis and tuberculids. Int J Dermatol 1999; 38:122-7. [PMID: 10192161 DOI: 10.1046/j.1365-4362.1999.00576.x] [Citation(s) in RCA: 68] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND The objective of this study was to explore the role of the polymerase chain reaction (PCR) fo the detection of Mycobacterium tuberculosis DNA as a diagnostic aid in cutaneous tuberculosis using routinely processed skin biopsy specimens. METHODS AND RESULTS A wide range of clinical specimens representing different forms of cutaneous tuberculosis and so-called tuberculids were studied. A sensitive and specific PCR assay targeting the sequence IS6110 of Mycobacterium tuberculosis complex was used. The specimens were categorized as follows. 1 Acid-fast bacilli (AFB) positive on biopsy (nine specimens from seven patients who were immunocompromised). PCR was positive in five specimens. Of these, one specimen was culture positive and three specimens were culture negative. 2 AFB negative on biopsy: (a) tuberculosis verrucosa cutis (23 specimens); (b) lupus vulgaris (three specimens); (c) cutaneous tuberculosis clinically suspected (six specimens). PCR was negative in all specimens. 3 Tuberculids.' (a) erythema induratum/nodular vasculitis (20 specimens); (b) papulonecrotic tuberculid (two specimens); (c) erythema nodosum (20 specimens). PCR was negative in all specimens. CONCLUSIONS The role of PCR in clinical dermatologic practice, at this stage, may be in differentiating between cutaneous tuberculosis and atypical mycobacterial infections in the context of an immunocompromised patient where AFB can be demonstrated on biopsy and cultures may be negative. In this clinical situation, PCR allows the prompt diagnosis and early institution of appropriate therapy. We have not found PCR to be a useful complement to the clinical and histologic diagnosis of "paucibacillary" forms of cutaneous tuberculosis.
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Tan BH, Nason E, Staeuber N, Jiang W, Monastryrskaya K, Roy P. RGD tripeptide of bluetongue virus VP7 protein is responsible for core attachment to Culicoides cells. J Virol 2001; 75:3937-47. [PMID: 11264382 PMCID: PMC114884 DOI: 10.1128/jvi.75.8.3937-3947.2001] [Citation(s) in RCA: 67] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Bluetongue virus (BTV) is an arthropod-borne virus transmitted by Culicoides species to vertebrate hosts. The double-capsid virion is infectious for Culicoides vector and mammalian cells, while the inner core is infectious for only Culicoides-derived cells. The recently determined crystal structure of the BTV core has revealed an accessible RGD motif between amino acids 168 to 170 of the outer core protein VP7, whose structure and position would be consistent with a role in cell entry. To delineate the biological role of the RGD sequence within VP7, we have introduced point mutations in the RGD tripeptide and generated three recombinant baculoviruses, each expressing a mutant derivative of VP7 (VP7-AGD, VP7-ADL, and VP7-AGQ). Each expressed mutant protein was purified, and the oligomeric nature and secondary structure of each was compared with those of the wild-type (wt) VP7 molecule. Each mutant VP7 protein was used to generate empty core-like particles (CLPs) and were shown to be biochemically and morphologically identical to those of wt CLPs. However, when mutant CLPs were used in an in vitro cell binding assay, each showed reduced binding to Culicoides cells compared to wt CLPs. Twelve monoclonal antibodies (MAbs) was generated using purified VP7 or CLPs as a source of antigen and were utilized for epitope mapping with available chimeric VP7 molecules and the RGD mutants. Several MAbs bound to the RGD motif on the core, as shown by immunogold labeling and cryoelectron microscopy. RGD-specific MAb H1.5, but not those directed to other regions of the core, inhibited the binding activity of CLPs to the Culicoides cell surface. Together, these data indicate that the RGD motif present on BTV VP7 is responsible for Culicoides cell binding activity.
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Tan B, Brzuskiewicz L. Separation of tocopherol and tocotrienol isomers using normal- and reverse-phase liquid chromatography. Anal Biochem 1989; 180:368-73. [PMID: 2817368 DOI: 10.1016/0003-2697(89)90447-8] [Citation(s) in RCA: 65] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
This optimization study for tocopherols and tocotrienols involved both normal- and reverse-phase liquid chromatography using various columns and mobile phases. Normal-phase systems showed elution of the homologs in order of increasing polarity with separation based on methyl substituents on the chromanol moiety. Reverse-phase systems showed class separation based on the saturation of the phytyl side chain; the more saturated tocopherols were retained on the column longer. When the Zorbax ODS was used with an isocratic ternary acetonitrile:methanol:methylene chloride (60:35:5) mixture, the optimized resolution was greater than 2.0 and separation was achieved in less than 13 min, but there was no separation of beta- and gamma-tocopherols. The normal-phase silica and amino columns provided separation of all available isomers with resolution greater than 1.1 and separation times of less than 5.5 and less than 10 min, respectively. Optimized isocratic binary solvent mixtures of hexane:2-propanol were used for silica (99:1) and amino (98:2) columns. Derivative spectra showed differences depending on substituents in the chromanol moiety but not the phytyl side chain. Second- and fourth-derivative spectra gave the best differentiation of the vitamin E isomers.
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Comparative Study |
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Cohen R, Shi Q, Meyers J, Jin Z, Svrcek M, Fuchs C, Couture F, Kuebler P, Ciombor KK, Bendell J, De Jesus-Acosta A, Kumar P, Lewis D, Tan B, Bertagnolli MM, Philip P, Blanke C, O'Reilly EM, Shields A, Meyerhardt JA. Combining tumor deposits with the number of lymph node metastases to improve the prognostic accuracy in stage III colon cancer: a post hoc analysis of the CALGB/SWOG 80702 phase III study (Alliance) ☆. Ann Oncol 2021; 32:1267-1275. [PMID: 34293461 DOI: 10.1016/j.annonc.2021.07.009] [Citation(s) in RCA: 62] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Revised: 07/14/2021] [Accepted: 07/15/2021] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND In colon cancer, tumor deposits (TD) are considered in assigning prognosis and staging only in the absence of lymph node metastasis (i.e. stage III pN1c tumors). We aimed to evaluate the prognostic value of the presence and the number of TD in patients with stage III, node-positive colon cancer. PATIENTS AND METHODS All participants from the CALGB/SWOG 80702 phase III trial were included in this post hoc analysis. Pathology reports were reviewed for the presence and the number of TD, lymphovascular and perineural invasion. Associations with disease-free survival (DFS) and overall survival (OS) were evaluated by multivariable Cox models adjusting for sex, treatment arm, T-stage, N-stage, lymphovascular invasion, perineural invasion and lymph node ratio. RESULTS Overall, 2028 patients were included with 524 (26%) TD-positive and 1504 (74%) TD-negative tumors. Of the TD-positive patients, 80 (15.4%) were node negative (i.e. pN1c), 239 (46.1%) were pN1a/b (<4 positive lymph nodes) and 200 (38.5%) were pN2 (≥4 positive lymph nodes). The presence of TD was associated with poorer DFS [adjusted hazard ratio (aHR) = 1.63, 95% CI 1.33-1.98] and OS (aHR = 1.59, 95% CI 1.24-2.04). The negative effect of TD was observed for both pN1a/b and pN2 groups. Among TD-positive patients, the number of TD had a linear negative effect on DFS and OS. Combining TD and the number of lymph node metastases, 104 of 1470 (7.1%) pN1 patients were re-staged as pN2, with worse outcomes than patients confirmed as pN1 (3-year DFS rate: 65.4% versus 80.5%, P = 0.0003; 5-year OS rate: 87.9% versus 69.1%, P = <0.0001). DFS was not different between patients re-staged as pN2 and those initially staged as pN2 (3-year DFS rate: 65.4% versus 62.3%, P = 0.4895). CONCLUSION Combining the number of TD and the number of lymph node metastases improved the prognostication accuracy of tumor-node-metastasis (TNM) staging.
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Journal Article |
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Tan BH, An H, Ohl CD. How Bulk Nanobubbles Might Survive. PHYSICAL REVIEW LETTERS 2020; 124:134503. [PMID: 32302159 DOI: 10.1103/physrevlett.124.134503] [Citation(s) in RCA: 58] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Revised: 02/28/2020] [Accepted: 03/03/2020] [Indexed: 05/23/2023]
Abstract
The existence of bulk nanobubbles has long been regarded with scepticism, due to the limitations of experimental techniques and the widespread assumption that spherical bubbles cannot achieve stable equilibrium. We develop a model for the stability of bulk nanobubbles based on the experimental observation that the zeta potential of spherical bubbles abruptly diverges from the planar value below 10 μm. Our calculations recover three persistently reported-but disputed-properties of bulk nanobubbles: that they stabilize at a typical radius of ∼100 nm, that this radius is bounded below 1 μm, and that it increases with ionic concentration.
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Abstract
BACKGROUND Oxytocin is the commonest induction agent used worldwide. It has been used alone, in combination with amniotomy or following cervical ripening with other pharmacological or non-pharmacological methods. Prior to the introduction of prostaglandin agents oxytocin was used as a cervical ripening agent as well. In developed countries oxytocin alone is more commonly used in the presence of ruptured membranes whether spontaneous or artificial. In developing countries where the incidence of HIV is high, delaying amniotomy in labour reduces vertical transmission rates and hence the use of oxytocin with intact membranes warrants further investigation. This review will address the use of oxytocin alone for induction of labour. Amniotomy alone or oxytocin with amniotomy for induction of labour has been reviewed elsewhere in the Cochrane Library. Trials which consider concomitant administration of oxytocin and amniotomy will not be considered. This is one of a series of reviews of methods of cervical ripening and labour induction using a standardised methodology. OBJECTIVES To determine the effects of oxytocin alone for third trimester cervical ripening or induction of labour in comparison with other methods of induction of labour or placebo/no treatment. SEARCH STRATEGY The Cochrane Pregnancy and Childbirth Group Trials Register, the Cochrane Controlled Trials Register and bibliographies of relevant papers. Last searched: May 2001. SELECTION CRITERIA The criteria for inclusion included the following: (1) clinical trials comparing vaginal prostaglandins used for third trimester cervical ripening or labour induction with placebo/no treatment or other methods listed above it on a predefined list of labour induction methods; (2) random allocation to the treatment or control group; (3) adequate allocation concealment; (4) violations of allocated management not sufficient to materially affect conclusions; (5) clinically meaningful outcome measures reported; (6) data available for analysis according to the random allocation; (7) missing data insufficient to materially affect the conclusions. DATA COLLECTION AND ANALYSIS A strategy was developed to deal with the large volume and complexity of trial data relating to labour induction. This involved a two-stage method of data extraction. The initial data extraction was done centrally, and incorporated into a series of primary reviews arranged by methods of induction of labour, following a standardised methodology. The data is to be extracted from the primary reviews into a series of secondary reviews, arranged by category of woman. MAIN RESULTS In total, 110 trials were considered; 52 have been excluded and 58 included examining a total of 11,129 women. Comparing oxytocin alone with expectant management: Oxytocin alone reduced the rate of unsuccessful vaginal delivery within 24 hours when compared with expectant management (8.3% versus 54%, relative risk (RR) 0.16, 95% confidence interval (CI) 0.10,0.25) but the caesarean section rate was increased (10.4% versus 8.9%, RR 1.17, 95% CI 1.01,1.36). This increase in caesarean section rate was not apparent in the subgroup analyses. Women were less likely to be unsatisfied with induction rather than expectant management, in the one trial reporting this outcome (5.5% versus 13.7%, RR 0.43, 95% CI 0.33, 0.56). Comparing oxytocin alone with vaginal prostaglandins: Oxytocin alone was associated with an increase in unsuccessful vaginal delivery within 24 hours (52% versus 28%, RR 1.85, 95% CI 1.41, 2.43), irrespective of membrane status, but there was no difference in caesarean section rates (11.4% versus 10%, RR 1.12, 95% CI 0.95, 1.33). Comparing oxytocin alone with intracervical prostaglandins: Oxytocin alone was associated with an increase in unsuccessful vaginal delivery within 24 hours when compared with intracervical PGE2 (51% versus 35%, RR 1.49, 95% CI 1.12,1.99). For all women with an unfavourable cervix regardless of membrane status, the caesarean section rates were increased (19.0% versus 13.1%, RR 1.42, 95% CI 1.11, 1.82). REVIEWER'S CONCLUSIONS Overall, comparison of oxytocin alone with either intravaginal or intracervical PGE2 reveals that the prostaglandin agents probably overall have more benefits than oxytocin alone. The amount of information relating to specific clinical subgroups is limited, especially with respect to women with intact membranes. Comparison of oxytocin alone to vaginal PGE2 in women with ruptured membranes reveals that both interventions are probably equally efficacious with each having some advantages and disadvantages over the others. With respect to current practice in women with ruptured membranes induction can be recommended by either method and in women with intact membranes there is insufficient information to make firm recommendations.
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