25 results on '"Tucker L"'
Search Results
2. Development and validation of the Kids Disability Screen for children with juvenile idiopathic arthritis: results from the CAPRI Registry.
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Houghton K, McPherson M, Surjanovic N, Loughin T, Berard R, Proulx-Gauthier JP, Chédeville G, Rumsey D, Schmeling H, Luca N, Johnson N, Gerschman T, Miettunen P, Tam H, Lim L, Morishita K, Scuccimarri R, Roth J, Duffy C, Tucker L, Feldman BM, and Guzman J
- Subjects
- Child, Humans, Surveys and Questionnaires, Canada, Disability Evaluation, Psychometrics, Registries, Health Status, Quality of Life, Reproducibility of Results, Cross-Cultural Comparison, Arthritis, Juvenile diagnosis, Rheumatology
- Abstract
Objective: The aim of this study was to develop and validate a brief disability screen for children with JIA, the Kids Disability Screen (KDS)., Methods: A total of 216 children enrolled in the Canadian Alliance of Pediatric Rheumatology Investigators (CAPRI) Registry in 2017-2018 formed a development cohort, and 220 children enrolled in 2019-2020 formed a validation cohort. At every clinic visit, parents answered two questions derived from the Childhood Health Assessment Questionnaire (CHAQ): 'Is it hard for your child to run and play BECAUSE OF ARTHRITIS?' ('Hard' 0-10), and 'Does your child usually need help from you or another person BECAUSE OF ARTHRITIS?' ('Help', 0-10). We used 36-fold cross-validation and tested nine different mathematical methods to combine the answers and optimize psychometric properties. The results were confirmed in the validation cohort., Results: Expressed as the mean of the two answers, KDS best balanced ease of use and psychometric properties, while a LASSO regression model combining the two answers with other patient characteristics [estimated CHAQ [eCHAQ]) had the highest responsiveness. In the validation cohort, 22.7%, 25.9% and 28.6% of patients had a score of 0 at enrolment for the KDS, eCHAQ and CHAQ, respectively. Responsiveness was 0.67, 0.74 and 0.62, respectively. Sensitivity to detect a CHAQ > 0 was 0.90 and specificity 0.56, KDS detecting some disability in 44% of children with a CHAQ = 0., Conclusion: This simple KDS has psychometric properties comparable with those of a full CHAQ and may be used at every clinic visit to identify those children who need a full disability assessment., (© The Author(s) 2022. Published by Oxford University Press on behalf of the British Society for Rheumatology. All rights reserved. For permissions, please email: journals.permissions@oup.com.)
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- 2022
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3. Tout le monde sur le pont : une approche multidisciplinaire du SRAS-CoV-2 associé au SIME.
- Author
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Lopez AA, Patel M, Rayment JH, Tam H, Roberts A, Laskin S, Tucker L, and Biggs CM
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- 2022
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4. Executive summary: The 2022 British Society for Rheumatology guideline for the treatment of psoriatic arthritis with biologic and targeted synthetic DMARDs.
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Tucker L, Allen A, Chandler D, Ciurtin C, Dick A, Foulkes A, Gullick N, Helliwell P, Jadon D, Jones G, Kyle S, Madhok V, McHugh N, Parkinson A, Raine T, Siebert S, Smith C, Tillett W, and Coates LC
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- Humans, Antirheumatic Agents therapeutic use, Arthritis, Psoriatic drug therapy, Biological Products therapeutic use, Rheumatology
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- 2022
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5. The 2022 British Society for Rheumatology guideline for the treatment of psoriatic arthritis with biologic and targeted synthetic DMARDs.
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Tucker L, Allen A, Chandler D, Ciurtin C, Dick A, Foulkes A, Gullick N, Helliwell P, Jadon D, Jones G, Kyle S, Madhok V, McHugh N, Parkinson A, Raine T, Siebert S, Smith C, Tillett W, and Coates LC
- Subjects
- Humans, Antirheumatic Agents therapeutic use, Arthritis, Psoriatic drug therapy, Biological Products therapeutic use, Rheumatology
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- 2022
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6. All hands on deck: A multidisciplinary approach to SARS-CoV-2-associated MIS-C.
- Author
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Lopez AA, Patel M, Rayment JH, Tam H, Roberts A, Laskin S, Tucker L, and Biggs CM
- Abstract
Background: Multisystem Inflammatory Syndrome in Children (MIS-C) is a post-infectious complication of SARS-CoV-2 infection with overlapping features of Kawasaki disease and toxic shock syndrome. In May 2020, a provincial multidisciplinary working group was established in anticipation of emerging cases following the first wave of SARS-CoV-2 infections., Methodology: Our centre established a multidisciplinary working group for MIS-C cases in British Columbia. The group developed guidelines using the World Health Organization MIS-C case definition. Guidelines were updated using quality improvement methods as new reports and our local experience evolved. We included all children who were evaluated in person or had samples sent to our centre for MIS-C evaluation from May 2020 to April 2021. We prospectively collected patient demographics, clinical and laboratory characteristics, and treatment., Results: Fifty-two children were included. Eleven were diagnosed as confirmed MIS-C. Ten of the 11 MIS-C cases presented with shock. Gastrointestinal and mucocutaneous involvement were also prominent. Common laboratory features included elevated C-reactive protein, D-dimer, troponin, and brain natriuretic peptide. Four out of 11 (36%) had myocardial dysfunction and 3/11 (27%) had coronary artery abnormalities. All 11 patients had evidence of SARS-CoV-2 infection. Ten out of 11 (91%) received intravenous (IV) immunoglobulin and IV corticosteroids., Conclusion: Our provincial cohort of MIS-C patients were more likely to present with shock and cardiac dysfunction, require ICU admission, and be treated with corticosteroids compared to ruled out cases. Our working group's evolving process ensured children with features of MIS-C were rapidly identified, had standardized evaluation, and received appropriate treatment in our province., (© The Author(s) 2022. Published by Oxford University Press on behalf of the Canadian Paediatric Society. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)
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- 2022
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7. Treatment of psoriatic arthritis with biologic and targeted synthetic DMARDs: British Society for Rheumatology guideline scope.
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Tillett W, Allen A, Tucker L, Chandler D, Ciurtin C, Davis C, Dick A, Foulkes A, Gullick N, Helliwell P, Jadon D, Jones G, Kyle S, Madhok V, McHugh N, Parkinson A, Raine T, Siebert S, Smith C, and Coates LC
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- Humans, Rheumatology standards, Treatment Outcome, Antirheumatic Agents therapeutic use, Arthritis, Psoriatic drug therapy, Biological Products therapeutic use
- Abstract
The aim of this guideline is to provide an update on evidence-based recommendations for treatment of adult patients with PsA. The previous BSR guidelines for PsA were published in 2012 and since that time, there have been many new advanced therapies licensed for PsA. This update will provide practical guidance for clinicians on the optimal selection of advanced therapies taking into account different domains of PsA (arthritis, enthesitis, dactylitis, axial disease and psoriasis) and key associated comorbidities. It will also update guidance on treatment strategy including the use of a treat-to-target approach. The guideline will be developed using the methods and processes outlined in Creating Clinical Guidelines: Our Protocol. (1) This development process to produce guidance, advice and recommendations for practice has National Institute for Health and Care Excellence (NICE) accreditation., (© The Author(s) 2020. Published by Oxford University Press on behalf of the British Society for Rheumatology. All rights reserved. For permissions, please email: journals.permissions@oup.com.)
- Published
- 2021
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8. Risk factors associated with Pneumocystis jirovecii pneumonia in juvenile myositis in North America.
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Sabbagh SE, Neely J, Chow A, DeGuzman M, Lai J, Lvovich S, McGrath T, Pereira M, Pinal-Fernandez I, Roberts J, Rouster-Stevens K, Schmeling H, Sura A, Tarshish G, Tucker L, Rider LG, and Kim S
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- Autoantibodies blood, Child, Female, Humans, Male, North America epidemiology, Opportunistic Infections diagnosis, Opportunistic Infections immunology, Opportunistic Infections mortality, Risk Assessment methods, Risk Assessment statistics & numerical data, Risk Factors, Asian People statistics & numerical data, Dermatomyositis blood, Dermatomyositis epidemiology, Dermatomyositis physiopathology, Dermatomyositis therapy, Immunosuppressive Agents therapeutic use, Interferon-Induced Helicase, IFIH1 immunology, Lung Diseases, Interstitial diagnosis, Lung Diseases, Interstitial etiology, Pneumonia, Pneumocystis diagnosis, Pneumonia, Pneumocystis immunology, Pneumonia, Pneumocystis mortality, Skin Ulcer diagnosis, Skin Ulcer etiology
- Abstract
Objectives: Pneumocystis jirovecii pneumonia (PJP) is associated with significant morbidity and mortality in adult myositis patients; however, there are few studies examining PJP in juvenile myositis [juvenile idiopathic inflammatory myopathy (JIIM)]. The purpose of this study was to determine the risk factors and clinical phenotypes associated with PJP in JIIM., Methods: An research electronic data capture (REDCap) questionnaire regarding myositis features, disease course, medications and PJP infection characteristics was completed by treating physicians for 13 JIIM patients who developed PJP (PJP+) from the USA and Canada. Myositis features and medications were compared with 147 JIIM patients without PJP (PJP-) from similar geographic regions who enrolled in National Institutes of Health natural history studies., Results: PJP+ patients were more often of Asian ancestry than PJP- patients [odds ratio (OR) 8.7; 95% CI 1.3, 57.9]. Anti- melanoma differentiation associated protein 5 (MDA5) autoantibodies (OR 12.5; 95% CI 3.0, 52.4), digital infarcts (OR 43.8; 95% CI 4.2, 460.2), skin ulcerations (OR 12.0; 95% CI 3.5, 41.2) and interstitial lung disease (OR 10.6; 95% CI 2.1, 53.9) were more frequent in PJP+ patients. Before PJP diagnosis, patients more frequently received pulse steroids, rituximab and more immunosuppressive therapy compared with PJP- patients. Seven PJP+ patients were admitted to the intensive care unit and four patients died due to PJP or its complications., Conclusions: PJP is a severe infection in JIIM that can be associated with mortality. Having PJP was associated with more immunosuppressive therapy, anti-MDA5 autoantibodies, Asian race and certain clinical features, including digital infarcts, cutaneous ulcerations and interstitial lung disease. Prophylaxis for PJP should be considered in juvenile myositis patients with these features., (© The Author(s) 2020. Published by Oxford University Press on behalf of the British Society for Rheumatology. All rights reserved. For permissions, please email: journals.permissions@oup.com.)
- Published
- 2021
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9. A new Canadian inception cohort for juvenile idiopathic arthritis: The Canadian Alliance of Pediatric Rheumatology Investigators Registry.
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Batthish M, Berard R, Cabral D, Bolaria R, Chédeville G, Duffy C, Gerhold K, Gerschman T, Huber A, Proulx-Gauthier JP, Rosenberg A, Rumsey D, Schmeling H, Shiff N, Soon G, Bruns A, Tucker L, and Guzman J
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- Adolescent, Antirheumatic Agents adverse effects, Arthritis, Juvenile diagnosis, Biological Factors adverse effects, Canada epidemiology, Child, Child, Preschool, Cohort Studies, Female, Humans, Incidence, Male, Prospective Studies, Registries, Severity of Illness Index, Treatment Outcome, Antirheumatic Agents therapeutic use, Arthritis, Juvenile drug therapy, Biological Factors therapeutic use, Rheumatology standards
- Abstract
Objectives: The aim was to describe the design, methods and initial findings of a new Canadian inception cohort of children with JIA, The Canadian Alliance of Pediatric Rheumatology Investigators (CAPRI) JIA Registry., Methods: The CAPRI JIA Registry was started in 2017 to collect information prospectively on children enrolled within 3 months of JIA diagnosis across Canada. The registry has a non-traditional modular design, with no artificially set times for registry visits to occur, streamlined multi-method data collection that requires 2-4 min per visit, and reports cumulative incidence of treatments, outcomes and adverse events calculated by Kaplan-Meier survival methods., Results: A total of 166 patients, enrolled a median of 6 weeks after JIA diagnosis at 10 centres, were included. The median age at diagnosis was 9 years [interquartile range (IQR) 3, 13], 61% were female and 51% had oligoarticular JIA. The median three-variable clinical Juvenile Arthritis Disease Activity Score was 6.5 (IQR 4, 10) at enrolment, and the median time to first attainment of clinically inactive disease (CID) was 24 weeks (by 1 year, 81%). Within 1 year of diagnosis, 70% of patients had started a DMARD and 35% a biologic agent. The rates of adverse events and serious adverse events were 60 and 5.8 per 100 patient-years, respectively., Conclusion: This streamlined and flexible registry minimizes the burden of data collection and interference with clinic operations. Initial findings suggest that treatments for newly diagnosed patients with JIA in Canada have intensified, and now 81% of patients attain CID within 1 year of diagnosis., (© The Author(s) 2020. Published by Oxford University Press on behalf of the British Society for Rheumatology. All rights reserved. For permissions, please email: journals.permissions@oup.com.)
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- 2020
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10. A comparison between childhood and adult onset systemic lupus erythematosus adjusted for ethnicity from the 1000 Canadian Faces of Lupus Cohort.
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Kim H, Levy DM, Silverman ED, Hitchon C, Bernatsky S, Pineau C, Smith CD, Tucker L, Petty R, Arbillaga H, Zummer M, Hudson M, Fortin P, Huber AM, Chedeville G, Peschken C, and Pope JE
- Abstract
Objective: Childhood-onset SLE (cSLE) manifests differently than adult-onset SLE (aSLE). This study determined whether ethnic differences contribute to the differences in clinical presentation between the two groups., Methods: This cross-sectional study used data from a multi-centred registry from eight adult and four paediatric Canadian centres gathered at study entry. We compared the frequency of clinical manifestations and autoantibodies between aSLE and cSLE. For those with a significant difference, a multivariable logistic regression was performed, adjusting for ethnicity, SLE onset (cSLE vs aSLE), disease duration and centre. Disease activity and damage between aSLE and cSLE were compared after stratifying by disease duration., Results: Of 552 aSLE subjects, 502 (90.9%) were female and 381 (69.0%) were Caucasian. Mean age at diagnosis was 37.0 ± 13.6 years and disease duration 10.9 ± 9.6 years. Of 276 cSLE subjects, 231 (83.7%) were female and 101 (36.6%) were Caucasian. Mean age at diagnosis was 12.7 ± 3.3 years and disease duration 5.6 ± 8.2 years. In multivariable regression analysis, aSLE was associated with decreased odds of having a neurologic disorder (odds ratio = 0.49) and increased odds of having aCL antibodies (odds ratio = 1.85). Disease activity and damage accrual scores were higher in aSLE than cSLE within the same disease duration strata, although the differences were not clinically significant. Ethnicity was not associated with any differences in clinical manifestations or autoantibody frequency between aSLE and cSLE., Conclusions: Although a crude comparison of aSLE and cSLE yielded several differences in clinical symptoms and autoantibodies, this difference was not attributable to ethnic differences between aSLE and cSLE., (© The Author(s) 2019. Published by Oxford University Press on behalf of the British Society for Rheumatology. All rights reserved. For permissions, please email: journals.permissions@oup.com.)
- Published
- 2019
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11. Glycogen synthase kinase 3 beta inhibits microRNA-183-96-182 cluster via the β-Catenin/TCF/LEF-1 pathway in gastric cancer cells.
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Tang X, Zheng D, Hu P, Zeng Z, Li M, Tucker L, Monahan R, Resnick MB, Liu M, and Ramratnam B
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- Active Transport, Cell Nucleus, Animals, Cell Nucleus metabolism, Cells, Cultured, Glycogen Synthase Kinase 3 antagonists & inhibitors, Glycogen Synthase Kinase 3 beta, Humans, Mice, MicroRNAs metabolism, Phenotype, Promoter Regions, Genetic, Signal Transduction, Stomach Neoplasms enzymology, Stomach Neoplasms metabolism, Transcriptional Activation, Gene Expression Regulation, Neoplastic, Glycogen Synthase Kinase 3 metabolism, Lymphoid Enhancer-Binding Factor 1 metabolism, MicroRNAs genetics, Stomach Neoplasms genetics, TCF Transcription Factors metabolism, beta Catenin metabolism
- Abstract
Glycogen synthase kinase 3 beta (GSK3β) is a critical protein kinase that phosphorylates numerous proteins in cells and thereby impacts multiple pathways including the β-Catenin/TCF/LEF-1 pathway. MicroRNAs (miRs) are a class of noncoding small RNAs of ∼22 nucleotides in length. Both GSK3β and miR play myriad roles in cell functions including stem cell development, apoptosis, embryogenesis and tumorigenesis. Here we show that GSK3β inhibits the expression of miR-96, miR-182 and miR-183 through the β-Catenin/TCF/LEF-1 pathway. Knockout of GSK3β in mouse embryonic fibroblast cells increases expression of miR-96, miR-182 and miR-183, coinciding with increases in the protein level and nuclear translocation of β-Catenin. In addition, overexpression of β-Catenin enhances the expression of miR-96, miR-182 and miR-183 in human gastric cancer AGS cells. GSK3β protein levels are decreased in human gastric cancer tissue compared with surrounding normal gastric tissue, coinciding with increases of β-Catenin protein, miR-96, miR-182, miR-183 and primary miR-183-96-182 cluster (pri-miR-183). Furthermore, suppression of miR-183-96-182 cluster with miRCURY LNA miR inhibitors decreases the proliferation and migration of AGS cells. Knockdown of GSK3β with siRNA increases the proliferation of AGS cells. Mechanistically, we show that β-Catenin/TCF/LEF-1 binds to the promoter of miR-183-96-182 cluster gene and thereby activates the transcription of the cluster. In summary, our findings identify a novel role for GSK3β in the regulation of miR-183-96-182 biogenesis through β-Catenin/TCF/LEF-1 pathway in gastric cancer cells.
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- 2014
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12. Can surveillance provide epidemiological data on Aboriginal health?
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Grenier D, Amed S, Dancey P, Dean H, Hadjiyannakis S, Hamilton J, Huber A, Pelletier L, Sellers E, Tucker L, Vaudry W, and Wong T
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- 2012
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13. Fertility awareness and parenting attitudes among American male and female undergraduate university students.
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Peterson BD, Pirritano M, Tucker L, and Lampic C
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- Adult, Age Factors, Female, Humans, Male, Maternal Age, United States, Attitude, Fertility, Parenting psychology, Reproductive Behavior psychology, Students psychology
- Abstract
Background: In the USA, the postponement of childbearing reflects contemporary social norms of delaying marriage, pursing educational goals and securing economic stability prior to attempting conception. Although university students are more likely to delay childbearing, it is unclear to what extent they are aware of age-related fertility decline. The current study is the first of its kind to assess fertility awareness and parenting attitudes of American undergraduate university students., Methods: Two-hundred forty-six randomly selected undergraduate university students (138 females and 108 males) completed an online self-report survey adapted from the Swedish Fertility Awareness Questionnaire. Students were evenly distributed between the freshman, sophomore, junior and senior classes with a mean age of 20.4 years., Results: Participants wanted to have their first and last child within the window of a woman's fertility. However, participants demonstrated a lack of fertility awareness by vastly overestimating the age at which women experience declines in fertility, the likelihood of pregnancy following unprotected intercourse and the chances that IVF treatments would be successful in the case of infertility. Nearly 9 in 10 participants want to have children in the future and viewed parenthood as a highly important aspect of their future lives., Conclusions: Delaying childbearing based on incorrect perceptions of female fertility could lead to involuntary childlessness. Education regarding fertility issues is necessary to help men and women make informed reproductive decisions that are based on accurate information rather than incorrect perceptions.
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- 2012
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14. Phosphorylation of the RNase III enzyme Drosha at Serine300 or Serine302 is required for its nuclear localization.
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Tang X, Zhang Y, Tucker L, and Ramratnam B
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- Cell Line, Cell Nucleus chemistry, Humans, Mass Spectrometry, MicroRNAs metabolism, Nuclear Localization Signals, Phosphorylation, RNA Processing, Post-Transcriptional, Ribonuclease III analysis, Ribonuclease III chemistry, Sequence Deletion, Cell Nucleus metabolism, Ribonuclease III metabolism, Serine metabolism
- Abstract
The RNaseIII enzyme Drosha plays a pivotal role in microRNA (miRNA) biogenesis by cleaving primary miRNA transcripts to generate precursor miRNA in the nucleus. The RNA binding and enzymatic domains of Drosha have been characterized and are on its C-terminus. Its N-terminus harbors a nuclear localization signal. Using a series of truncated Drosha constructs, we narrowed down the segment responsible for nuclear translocation to a domain between aa 270 and aa 390. We further identified two phosphorylation sites at Serine300 (S300) and Serine302 (S302) by mass spectrometric analysis. Double mutations of S→A at S300 and S302 completely disrupted nuclear localization. Single mutation of S→A at S300 or S302, however, had no effect on nuclear localization indicating that phosphorylation at either site is sufficient to locate Drosha to the nucleus. Furthermore, mimicking phosphorylation status by mutating S→E at S300 and/or S→D at S302 restored nuclear localization. Our findings add a further layer of complexity to the molecular anatomy of Drosha as it relates to miRNA biogenesis.
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- 2010
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15. Concentrations and significance of cytokines and other immunologic factors in semen of healthy fertile men.
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Politch JA, Tucker L, Bowman FP, and Anderson DJ
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- Adult, Chemokines metabolism, Fertility, Granulocytes cytology, Granulocytes metabolism, Humans, Immune System, Immunoglobulins chemistry, Lymphokines metabolism, Male, Neutrophils metabolism, Reference Values, Spermatozoa metabolism, Cytokines metabolism, Enzyme-Linked Immunosorbent Assay methods, Semen physiology
- Abstract
Background: The purpose of this study was to establish normal reference values for several immunologic factors in semen to provide a foundation for understanding their physiologic significance in health and disease., Methods: Semen from 83 healthy, fertile men was assessed by Bio-Plex or enzyme-linked immunosorbent assay to determine quantities of immunoglobulin (Ig) isotypes, chemokines, cytokines and growth factors. We also enumerated polymorphonuclear granulocytes (PMN) by peroxidase staining to examine the association of inflammation with levels of these factors., Results: High concentrations of IgG and IgA were detected in all samples. IgG concentrations were significantly higher than IgA concentrations (P < 0.0001). Likewise, two multifunctional growth factors, transforming growth factor-beta1 and interleukin (IL)-7, and three chemokines, stromal cell-derived factor-1alpha, monocyte chemotactic/chemoattractant protein-1 and IL-8, were present in high concentrations in all samples (medians >1000 pg/ml). Other soluble factors were detectable in low concentration (medians <150 pg/ml), either in a majority of samples [IL-1alpha and beta, IL-5, IL-6, IL-13, IL-17, regulated on activation normal T cell expressed and secreted (RANTES), macrophage inflammatory protein (MIP)-1beta, interferon (IFN)-alpha and granulocyte colony-stimulating factor (CSF)], or in a minority of samples (MIP-1alpha, IL-2, IL-10, IL-12, TNF-alpha, IFN-gamma and granulocyte-macrophage-CSF). PMN counts significantly correlated with IL-1beta, IL-6, TNF-alpha, MIP-1alpha, MIP-1beta, IL-13 and IgA concentrations., Conclusions: The semen of healthy, fertile men contains a broad array of immunologic factors. These normative values can serve as a foundation for future studies on the role of these factors in infertility, genital tract infections and other pathologic conditions.
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- 2007
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16. Enhanced gene silencing of HIV-1 specific siRNA using microRNA designed hairpins.
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Boden D, Pusch O, Silbermann R, Lee F, Tucker L, and Ramratnam B
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- Base Sequence, Cell Line, Gene Products, tat genetics, HIV Core Protein p24 biosynthesis, HIV-1 physiology, Humans, MicroRNAs genetics, Molecular Sequence Data, Nucleic Acid Conformation, RNA, Small Interfering genetics, RNA, Viral metabolism, Transfection, Virus Replication, tat Gene Products, Human Immunodeficiency Virus, HIV-1 genetics, MicroRNAs chemistry, RNA Interference, RNA, Small Interfering chemistry
- Abstract
Post-transcriptional inhibition of HIV-1 replication can be achieved by RNA interference (RNAi). The cellular expression of short interfering RNA (siRNA) or short hairpin RNA (shRNA) homologous to regions of the HIV-1 genome decreases viral replication by the selective degradation of targeted RNA. Here, we demonstrate that another class of noncoding regulatory RNA, termed microRNA (miRNA), can be used to deliver antiviral RNAi. By incorporating sequences encoding siRNA targeting the HIV-1 transactivator protein tat into a human miR-30 pre-microRNA (pre-miRNA) backbone, we were able to express tat siRNA in cells. The tat siRNA delivered as pre-miRNA precursor was 80% more effective in reducing HIV-1 p24 antigen production than tat siRNA expressed as conventional shRNA. Our results confirm the utility of expressing HIV-1 specific siRNA through a miR-30 precursor stem-loop structure and suggest that this strategy can be used to increase the antiviral potency of RNAi.
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- 2004
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17. Nucleotide sequence homology requirements of HIV-1-specific short hairpin RNA.
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Pusch O, Boden D, Silbermann R, Lee F, Tucker L, and Ramratnam B
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- Base Sequence, Blotting, Northern, Cell Line, Gene Products, gag genetics, Genetic Vectors genetics, HIV Core Protein p24 genetics, Humans, Oligonucleotides genetics, Point Mutation, RNA, Viral genetics, RNA, Viral metabolism, Reverse Transcriptase Polymerase Chain Reaction, Sequence Homology, Nucleic Acid, HIV-1 genetics, RNA Interference, RNA, Small Interfering genetics
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The degradation of a selected mRNA species by RNA interference requires a high degree of homology between the short interfering or short hairpin RNA (si or shRNA) and its target. Recent reports have demonstrated that the number and location of nucleotide mismatches affect the activity of si/shRNA. Here, we systematically examined the effect of single nucleotide mutations in all 21 positions of an effective shRNA that targets the gag gene of HIV-1. We found that all mutant shRNAs exerted RNAi activity but were less effective in gene silencing compared to the wild-type gag shRNA. The most pronounced reduction in function was observed with mutations in the central and 5' regions of the shRNA. Our results demonstrate that optimal gene silencing requires perfect homology between shRNA and the chosen target, but that a variable degree of silencing occurs, depending upon the precise location of nucleotide mismatches.
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- 2003
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18. Promoter choice affects the potency of HIV-1 specific RNA interference.
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Boden D, Pusch O, Lee F, Tucker L, Shank PR, and Ramratnam B
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- Cell Line, Gene Expression Regulation, Viral, Gene Products, tat genetics, Humans, RNA, Small Interfering genetics, RNA, Small Interfering metabolism, RNA, Transfer, Met genetics, RNA, Viral genetics, RNA, Viral metabolism, Transfection, tat Gene Products, Human Immunodeficiency Virus, HIV-1 genetics, Promoter Regions, Genetic genetics, RNA Interference
- Abstract
RNA interference (RNAi) is mediated by small interfering (si) RNAs that target and degrade mRNA in a sequence-specific manner. Cellular expression of siRNA can be achieved by the use of expression cassettes driven by RNA polymerase III (pol III) promoters. Here, we demonstrate that a modified tRNA(met)-derived (MTD) promoter effectively drives the cellular expression of HIV-1-specific siRNA. We observed up to 56% greater inhibition of virus production when the MTD promoter was used to drive the expression of short hairpin (sh) RNA targeting the HIV-1 transactivator protein tat compared to cassettes containing other pol III promoters such as H1, U6+1 and U6+27. We conclude that the MTD promoter is ideally suited to drive intracellular expression of HIV-1 specific siRNA and may serve as an important component of future RNAi vector delivery systems.
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- 2003
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19. The molecular basis of nonoxynol-9-induced vaginal inflammation and its possible relevance to human immunodeficiency virus type 1 transmission.
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Fichorova RN, Tucker LD, and Anderson DJ
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- Adult, Cell Line, Transformed, Cervix Uteri cytology, Cervix Uteri drug effects, Cervix Uteri immunology, Chemokines biosynthesis, Cytokines biosynthesis, Female, HIV Infections virology, HIV-1 genetics, Humans, Inflammation Mediators metabolism, Interleukin-1 metabolism, Middle Aged, NF-kappa B genetics, NF-kappa B metabolism, Nonoxynol administration & dosage, Risk Factors, Therapeutic Irrigation, Tumor Cells, Cultured, Vagina cytology, Vagina drug effects, Vagina immunology, HIV Infections transmission, HIV-1 physiology, Nonoxynol adverse effects, Vaginitis chemically induced
- Abstract
Topical microbicides are being sought to prevent sexually transmitted diseases by inactivating pathogens while preserving or enhancing the natural mucosal barrier. Serious public health concerns were raised by a recent phase 3 clinical trial that showed that nonoxynol-9 (N-9), a leading microbicide candidate widely used as an over-the-counter spermicide, may actually increase human immunodeficiency virus type 1 (HIV-1) transmission. The present study links N-9-induced vaginal inflammation to increased risk of HIV-1 infection. Analysis of molecular and cellular components in cervicovaginal secretions, as well as results from in vitro activation of cervicovaginal epithelial cells and U1/HIV promonocytic cells, showed that multiple N-9 use can promote HIV-1 transmission through interleukin-1-mediated NF-kappaB activation, which leads to chemokine-induced recruitment of HIV-1 host cells and increased HIV-1 replication in infected cells. Furthermore, this study identifies in vitro and in vivo model systems for monitoring undesirable proinflammatory effects of microbicides and other vaginal products.
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- 2001
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20. Genital tract human immunodeficiency virus type 1 (HIV-1) shedding and inflammation and HIV-1 env diversity in perinatal HIV-1 transmission.
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Panther LA, Tucker L, Xu C, Tuomala RE, Mullins JI, and Anderson DJ
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- Cervix Uteri immunology, Cervix Uteri virology, Cohort Studies, DNA, Viral analysis, Female, Genitalia, Female virology, HIV Infections immunology, HIV Infections virology, HIV-1 physiology, Humans, Infant, Infant, Newborn, Infectious Disease Transmission, Vertical, Neutrophils immunology, Nucleic Acid Heteroduplexes analysis, Polymerase Chain Reaction, Pregnancy, Proviruses, RNA, Viral analysis, Vagina immunology, Vagina virology, Viral Load, Virus Shedding, Gene Products, env genetics, Genetic Variation, HIV Infections transmission, HIV-1 genetics, Pregnancy Complications, Infectious virology
- Abstract
This study sought to identify genital tract characteristics associated with vertical transmission of human immunodeficiency virus type 1 (HIV-1). HIV-1 DNA and RNA, HIV-1 env diversity, and inflammatory cells were quantified in cervicovaginal lavages (CVLs) of 24 women enrolled in the Women and Infants Transmission Study; 7 women transmitted HIV-1 perinatally. Vaginal candidiasis, HIV-1 culture positivity, levels of HIV-1 DNA and cell-free RNA, and HIV-1 env diversity were significantly higher in the CVLs of transmitters. CVL HIV-1 DNA levels correlated with higher levels of inflammatory cells and cell-free HIV-1 RNA. Of subjects with paired blood and CVL specimens, there was more HIV-1 env heterogeneity between blood and CVLs in transmitters than in nontransmitters. In summary, increased HIV-1 shedding is correlated with a more complex population of HIV-1 quasispecies in the genital tracts of parturient women, which may increase the probability that a fetotropic strain is transmitted.
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- 2000
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21. Persistence of human immunodeficiency virus in semen after adding indinavir to combination antiretroviral therapy.
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Mayer KH, Boswell S, Goldstein R, Lo W, Xu C, Tucker L, DePasquale MP, D'Aquila R, and Anderson DJ
- Subjects
- CD4 Lymphocyte Count, DNA, Viral analysis, Drug Therapy, Combination, HIV Protease genetics, HIV-1 isolation & purification, Humans, Longitudinal Studies, Male, RNA, Viral analysis, Anti-HIV Agents administration & dosage, HIV Protease Inhibitors administration & dosage, HIV-1 drug effects, Indinavir administration & dosage, Semen virology
- Abstract
Changes in human immunodeficiency virus (HIV) type 1 concentration and protease genotype were evaluated in semen specimens from 22 HIV-positive men before and 6 months after the addition of indinavir to dual nucleoside therapy. Seminal HIV was detected by polymerase chain reaction analysis for DNA or RNA for 59% of men before combination treatment and persisted at 6 months for 31% of the men who initially had seminal HIV detected (P = .026). The maximum levels of cell-free RNA, cell-associated RNA, and proviral DNA in semen before treatment and at 6 months were 400,000 and 10,000 copies/mL, 70,000 and 27,000 copies/mL, and 80,000 and 3,000 copies/mL, respectively. Three of the four men with persistent seminal DNA had plasma viral loads of > 10,000 copies/mL before treatment. One patient who became intolerant to indinavir had seminal HIV RNA detected by PCR analysis after 6 months. Although none of the cultures of semen specimens from the four men with PCR analysis-detectable seminal DNA after 6 months yielded HIV, indinavir resistance mutations were identified in a seminal leukocyte DNA specimen from one patient, and a second patient whose therapy was switched to saquinavir had different protease inhibitor resistance mutations in seminal and blood leukocyte DNA specimens. HIV-1 protease inhibitor resistance mutants may emerge in the semen of patients receiving combination therapy.
- Published
- 1999
- Full Text
- View/download PDF
22. Anti-MPO in adult- and childhood-onset SLE.
- Author
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Isenberg DA, Tucker LB, and Cambridge G
- Subjects
- Adult, Child, Female, Humans, Immunoglobulin G blood, Immunoglobulin M blood, Male, Autoantibodies blood, Lupus Erythematosus, Systemic immunology, Peroxidase immunology
- Published
- 1997
- Full Text
- View/download PDF
23. Factors associated with increased levels of human immunodeficiency virus type 1 DNA in semen.
- Author
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Xu C, Politch JA, Tucker L, Mayer KH, Seage GR 3rd, and Anderson DJ
- Subjects
- CD4 Lymphocyte Count, Cells, Cultured, DNA, Viral blood, Genital Diseases, Male immunology, HIV Infections blood, HIV-1 growth & development, Humans, Immunohistochemistry, Inflammation, Leukocytes virology, Male, Polymerase Chain Reaction, Proviruses genetics, Semen cytology, Viral Load, DNA, Viral analysis, HIV Infections transmission, HIV Infections virology, HIV-1 genetics, Semen virology
- Abstract
Human immunodeficiency virus type 1 (HIV-1)-infected cells have been isolated from semen and may be a major source of transmissible virus. Quantitative polymerase chain reaction (PCR) assay was used to determine HIV proviral DNA load in cellular fractions of semen from 74 antiviral therapy-naive HIV-1-seropositive men and 53 paired blood samples. HIV-1 DNA was detected in 65% of semen (range: <10-5000 copies/mL) and 100% of blood samples (range: 20-2500 copies/mL). HIV-1 DNA copy numbers in semen correlated significantly with those in blood, but for most cases, the concentration of blood HIV-1 DNA was higher (mean blood-to-semen ratio = 2.9). Factors associated with elevated HIV-1 provirus levels in semen included reduced peripheral CD4 cell count and asymptomatic genital tract inflammation (>10(6) white blood cells/mL of semen). These data provide evidence that genital tract inflammation and reduced peripheral CD4 cell count may be associated with enhanced sexual transmission of HIV-1 because of increased numbers of HIV-1-infected cells in semen.
- Published
- 1997
- Full Text
- View/download PDF
24. Adult- and childhood-onset systemic lupus erythematosus: a comparison of onset, clinical features, serology, and outcome.
- Author
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Tucker LB, Menon S, Schaller JG, and Isenberg DA
- Subjects
- Adolescent, Adult, Age of Onset, Antigen-Antibody Reactions, Black People, Cohort Studies, Female, Humans, Lupus Erythematosus, Systemic immunology, Male, Survival Analysis, White People, Lupus Erythematosus, Systemic epidemiology, Lupus Erythematosus, Systemic physiopathology
- Abstract
This study examines the differences which may distinguish systemic lupus erythematosus (SLE) presenting in adult life or childhood. A common database was established, with analysis of clinical, serological and outcome features of a cohort of patients with SLE, with disease diagnosed before the age of 16 (n = 39) or after the age of 16 (n = 165). Disease onset was generally more severe in the childhood-onset patients. Cardiopulmonary disease was more common in the older-onset group, but major haematological manifestations were more frequent in the childhood-onset group. Serologically, anti-DNA, anti-Sm and anti-RNP antibodies and a low C3 were all found more frequently in the younger patients. Twice as many adult-onset cases had died at the time of the last follow-up (10 vs 5%), but this group had been followed for a longer period (average 7.5 yr, S.D. 3.9 for adults vs average 4.8 yr, S.D. 3.2 for children). However, the younger patients were twice as likely (82 vs 40%) to require high-dose prednisone, although the requirement for immunosuppressive agents was similar in the two groups. Clinicians should anticipate that children with SLE have a more severe disease onset than adults in general.
- Published
- 1995
- Full Text
- View/download PDF
25. Felodipine as a replacement for minoxidil in the treatment of severe hypertension.
- Author
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Wathen CG, MacLeod D, Tucker L, and Muir AL
- Subjects
- Aged, Calcium Channel Blockers pharmacology, Felodipine, Heart Rate drug effects, Humans, Male, Middle Aged, Minoxidil pharmacology, Nitrendipine pharmacology, Nitrendipine therapeutic use, Random Allocation, Calcium Channel Blockers therapeutic use, Hypertension, Malignant drug therapy, Minoxidil therapeutic use, Nitrendipine analogs & derivatives
- Abstract
The new calcium antagonist felodipine has been compared with minoxidil in the management of severe hypertension in a group of 17 men. Satisfactory control of blood pressure was achieved in all patients with a combination of beta blocker, loop diuretic and minoxidil after inadequate control on a standard regimen of beta blocker, thiazide and vasodilator. The optimal dose of felodipine was titrated after a placebo phase. In a double blind crossover trial blood pressure on felodipine (150/88 +/- 19/8 mmHg, SD) was the same as on minoxidil (148/87 +/- 23/11 mmHg, NS) and the postural difference was similar (NS) on both drug regimens. Body weight was lower on the felodipine regimen (P less than 0.01), as was supine heart rate (P less than 0.05). There was a small rise in plasma liver enzymes on felodipine therapy (P less than 0.01). Felodipine was well tolerated and may be useful in the management of severe hypertension.
- Published
- 1986
- Full Text
- View/download PDF
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