1
|
Weinstock LB, Brook JB, Molderings GJ. Efficacy and toxicity of hydroxyurea in mast cell activation syndrome patients refractory to standard medical therapy: retrospective case series. Naunyn Schmiedebergs Arch Pharmacol 2022; 395:1441-1447. [PMID: 35982335 PMCID: PMC9388361 DOI: 10.1007/s00210-022-02282-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2022] [Accepted: 08/11/2022] [Indexed: 12/04/2022]
Abstract
Determine efficacy and adverse events (AEs) of hydroxyurea (HU) in mast cell activation syndrome (MCAS) patients who were refractory to standard medical therapy. An electronic chart review was performed to find MCAS patients who received HU in a MCAS medical practice. Diagnosis of MCAS was established on the basis of mast cell (MC) activation symptoms in ≥ 5 systems plus ≥ 1 abnormal MC mediators and/or ≥ 20 MC/high power field on duodenal biopsies. Medicines not providing significant clinical improvement prior to HU were tabulated. The following symptoms were evaluated by patients on a 0–10 scale prior to and at the study conclusion: bone pain, abdominal pain, diarrhea, bloating, and nausea. Safety labs were obtained on a regular basis. Twenty out of three hundred ten (8.4%) MCAS patients received HU. Patients included 22 females, average age 42.4 years. Dysautonomia was present in 60%. An average of 10.6 (SD 1.7, range 8–13) medications were used prior to adding HU to various concomitant medications. Average dose of HU was 634 mg. In 20 patients who continued therapy for ≥ 2 months, there was statistically significant reduction of bone pain, abdominal pain, diarrhea, bloating, and nausea. Fourteen patients noted prolonged success with therapy. Six patients stopped HU within 6 weeks owing to AEs. Four patients treated ≥ 2 months had AEs and 2 led to HU cessation. All AEs were reversible. Refractory MCAS patients showed clear significant improvement in bone pain and gastrointestinal symptoms on HU. Systematic monitoring was effective in preventing the occurrence of severe HU-induced adverse events.
Collapse
Affiliation(s)
- Leonard B Weinstock
- Clinical Medicine, Department of Medicine, Washington University School of Medicine, President, Specialists in Gastroenterology, 11525 Olde Cabin Road, St. Louis, MO, 63141, USA
| | | | | |
Collapse
|
2
|
Tsai YC, Tsai TF. Oral disease-modifying antirheumatic drugs and immunosuppressants with antiviral potential, including SARS-CoV-2 infection: a review. Ther Adv Musculoskelet Dis 2020; 12:1759720X20947296. [PMID: 32952617 PMCID: PMC7476354 DOI: 10.1177/1759720x20947296] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Accepted: 06/02/2020] [Indexed: 12/23/2022] Open
Abstract
There have been several episodes of viral infection evolving into epidemics in recent decades, and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the latest example. Its high infectivity and moderate mortality have resulted in an urgent need to find an effective treatment modality. Although the category of immunosuppressive drugs usually poses a risk of infection due to interference of the immune system, some of them have been found to exert antiviral properties and are already used in daily practice. Recently, hydroxychloroquine and baricitinib have been proposed as potential drugs for SARS-CoV-2. In fact, there are other immunosuppressants known with antiviral activities, including cyclosporine A, hydroxyurea, minocycline, mycophenolic acid, mycophenolate mofetil, leflunomide, tofacitinib, and thalidomide. The inherent antiviral activity could be a treatment choice for patients with coexisting rheumatological disorders and infections. Clinical evidence, their possible mode of actions and spectrum of antiviral activities are included in this review article. LAY SUMMARY Immunosuppressants often raise the concern of infection risks, especially for patients with underlying immune disorders. However, some disease-modifying antirheumatic drugs (DMARDs) with inherent antiviral activity would be a reasonable choice in the situation of concomitant viral infections and flare up of autoimmune diseases. This review covers DMARDs of treatment potential for SARS-CoV-2 in part I, and antiviral mechanisms plus trial evidence for viruses other than SARS-CoV-2 in part II.
Collapse
Affiliation(s)
- Y. C. Tsai
- Department of Dermatology, Far Eastern Memorial Hospital, New Taipei city, Taiwan
| | - T. F. Tsai
- Department of Dermatology, National Taiwan University Hospital and National Taiwan University College of Medicine, No. 7, Zhongshan S. Rd, Zhongzheng District, Taipei City 100, Taiwan
| |
Collapse
|
3
|
Yahouédéhou SCMA, Adorno EV, da Guarda CC, Ndidi US, Carvalho SP, Santiago RP, Aleluia MM, de Oliveira RM, Gonçalves MDS. Hydroxyurea in the management of sickle cell disease: pharmacogenomics and enzymatic metabolism. THE PHARMACOGENOMICS JOURNAL 2018; 18:730-739. [DOI: 10.1038/s41397-018-0045-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2017] [Revised: 06/20/2018] [Accepted: 08/10/2018] [Indexed: 02/06/2023]
|
4
|
Shen JP, Zhao D, Sasik R, Luebeck J, Birmingham A, Bojorquez-Gomez A, Licon K, Klepper K, Pekin D, Beckett A, Sanchez K, Thomas A, Kuo CC, Du D, Roguev A, Lewis NE, Chang AN, Kreisberg JF, Krogan N, Qi L, Ideker T, Mali P. Combinatorial CRISPR-Cas9 screens for de novo mapping of genetic interactions. Nat Methods 2017; 14:573-576. [PMID: 28319113 PMCID: PMC5449203 DOI: 10.1038/nmeth.4225] [Citation(s) in RCA: 231] [Impact Index Per Article: 33.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2016] [Accepted: 02/17/2017] [Indexed: 12/13/2022]
Abstract
We developed a systematic approach to map human genetic networks by combinatorial CRISPR-Cas9 perturbations coupled to robust analysis of growth kinetics. We targeted all pairs of 73 cancer genes with dual guide RNAs in three cell lines, comprising 141,912 tests of interaction. Numerous therapeutically relevant interactions were identified, and these patterns replicated with combinatorial drugs at 75% precision. From these results, we anticipate that cellular context will be critical to synthetic-lethal therapies.
Collapse
Affiliation(s)
- John Paul Shen
- Department of Medicine, Division of Genetics, University of California, San Diego; La Jolla, CA, 92093, USA
- Moores UCSD Cancer Center; La Jolla, CA, 92093, USA
- The Cancer Cell Map Initiative (CCMI), University of California, San Diego; La Jolla, CA, 92093, USA
| | - Dongxin Zhao
- The Cancer Cell Map Initiative (CCMI), University of California, San Diego; La Jolla, CA, 92093, USA
- Department of Bioengineering, University of California, San Diego; La Jolla, CA, 92093, USA
| | - Roman Sasik
- Center for Computational Biology & Bioinformatics, University of California, San Diego; La Jolla, CA, 92093, USA
| | - Jens Luebeck
- Bioinformatics & Systems Biology Program, University of California, San Diego; La Jolla, CA, 92093, USA
| | - Amanda Birmingham
- Center for Computational Biology & Bioinformatics, University of California, San Diego; La Jolla, CA, 92093, USA
| | - Ana Bojorquez-Gomez
- Department of Medicine, Division of Genetics, University of California, San Diego; La Jolla, CA, 92093, USA
| | - Katherine Licon
- Department of Medicine, Division of Genetics, University of California, San Diego; La Jolla, CA, 92093, USA
| | - Kristin Klepper
- Department of Medicine, Division of Genetics, University of California, San Diego; La Jolla, CA, 92093, USA
| | - Daniel Pekin
- Department of Medicine, Division of Genetics, University of California, San Diego; La Jolla, CA, 92093, USA
| | - Alex Beckett
- Department of Medicine, Division of Genetics, University of California, San Diego; La Jolla, CA, 92093, USA
| | - Kyle Sanchez
- Department of Medicine, Division of Genetics, University of California, San Diego; La Jolla, CA, 92093, USA
| | - Alex Thomas
- Bioinformatics & Systems Biology Program, University of California, San Diego; La Jolla, CA, 92093, USA
- Novo Nordisk Center for Biosustainability at the University of California, San Diego; La Jolla, CA 92093, USA
| | - Chih-Chung Kuo
- Department of Bioengineering, University of California, San Diego; La Jolla, CA, 92093, USA
- Novo Nordisk Center for Biosustainability at the University of California, San Diego; La Jolla, CA 92093, USA
| | - Dan Du
- The Cancer Cell Map Initiative (CCMI), University of California, San Diego; La Jolla, CA, 92093, USA
- Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, Department of Cell and Tissue Biology, University of California, San Francisco, CA 94143, USA
| | - Assen Roguev
- The Cancer Cell Map Initiative (CCMI), University of California, San Diego; La Jolla, CA, 92093, USA
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco CA 94143, USA University of California, San Francisco
| | - Nathan E. Lewis
- Department of Pediatrics, University of California, San Diego; La Jolla, CA, 92093, USA
- Novo Nordisk Center for Biosustainability at the University of California, San Diego; La Jolla, CA 92093, USA
| | - Aaron N. Chang
- Center for Computational Biology & Bioinformatics, University of California, San Diego; La Jolla, CA, 92093, USA
| | - Jason F. Kreisberg
- Department of Medicine, Division of Genetics, University of California, San Diego; La Jolla, CA, 92093, USA
- The Cancer Cell Map Initiative (CCMI), University of California, San Diego; La Jolla, CA, 92093, USA
| | - Nevan Krogan
- The Cancer Cell Map Initiative (CCMI), University of California, San Diego; La Jolla, CA, 92093, USA
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco CA 94143, USA University of California, San Francisco
| | - Lei Qi
- The Cancer Cell Map Initiative (CCMI), University of California, San Diego; La Jolla, CA, 92093, USA
- Department of Bioengineering, Stanford University, Stanford, CA, 94305, USA
| | - Trey Ideker
- Department of Medicine, Division of Genetics, University of California, San Diego; La Jolla, CA, 92093, USA
- Moores UCSD Cancer Center; La Jolla, CA, 92093, USA
- The Cancer Cell Map Initiative (CCMI), University of California, San Diego; La Jolla, CA, 92093, USA
- Center for Computational Biology & Bioinformatics, University of California, San Diego; La Jolla, CA, 92093, USA
| | - Prashant Mali
- Moores UCSD Cancer Center; La Jolla, CA, 92093, USA
- The Cancer Cell Map Initiative (CCMI), University of California, San Diego; La Jolla, CA, 92093, USA
- Department of Bioengineering, University of California, San Diego; La Jolla, CA, 92093, USA
| |
Collapse
|
5
|
Sobota A, Sabharwal V, Fonebi G, Steinberg M. How we prevent and manage infection in sickle cell disease. Br J Haematol 2015; 170:757-67. [PMID: 26018640 DOI: 10.1111/bjh.13526] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Sickle cell disease (SCD) affects approximately 100,000 people in the US, 12,500 in the UK, and millions worldwide. SCD is typified by painful vaso-occlusive episodes, haemolytic anaemia and organ damage. A secondary complication is infection, which can be bacterial, fungal or viral. Universal newborn screening, routine use of penicillin prophylaxis, availability of conjugated vaccines against S. pneumoniae and comprehensive care programmes instituted during the past few decades in industrialized countries have dramatically reduced childhood mortality and improved life expectancy. Yet patients with SCD remain at increased risk of infection. Unfortunately, the treatment of most bacterial infections that are common in SCD is not based on the results of randomized controlled clinical trials. In their absence, treatment decisions are based on consensus guidelines, clinical experience or adapting treatment applied in other diseases. This leads to wide variation in treatment among institutions and even between treating physicians in a single institution. Prevention of infection, when possible, is most important and we focus on prevention through targeted prophylaxis and vaccination. We will share our management strategies for managing the more common infections in SCD and provide the rationale for our recommendations.
Collapse
Affiliation(s)
- Amy Sobota
- Boston University School of Medicine, Boston, MA, USA.,Department of Pediatrics, Boston Medical Center, Boston, MA, USA
| | - Vishakha Sabharwal
- Boston University School of Medicine, Boston, MA, USA.,Department of Pediatrics, Boston Medical Center, Boston, MA, USA
| | - Gwendoline Fonebi
- Boston University School of Medicine, Boston, MA, USA.,Department of Medicine, Boston Medical Center, Boston, MA, USA
| | - Martin Steinberg
- Boston University School of Medicine, Boston, MA, USA.,Department of Medicine, Boston Medical Center, Boston, MA, USA
| |
Collapse
|
6
|
Passaes CP, Sáez-Cirión A. HIV cure research: advances and prospects. Virology 2014; 454-455:340-52. [PMID: 24636252 DOI: 10.1016/j.virol.2014.02.021] [Citation(s) in RCA: 96] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2014] [Revised: 02/18/2014] [Accepted: 02/20/2014] [Indexed: 12/16/2022]
Abstract
Thirty years after the identification of HIV, a cure for HIV infection is still to be achieved. Advances of combined antiretroviral therapy (cART) in recent years have transformed HIV infection into a chronic disease when treatment is available. However, in spite of the favorable outcomes provided by the newer therapies, cART is not curative and patients are at risk of developing HIV-associated disorders. Moreover, universal access to antiretroviral treatment is restricted by financial obstacles. This review discusses the most recent strategies that have been developed in the search for an HIV cure and to improve life quality of people living with HIV.
Collapse
Affiliation(s)
- Caroline P Passaes
- Unité de Régulation des Infections Rétrovirales, Institut Pasteur, 25-28 rue du Dr Roux, 75724 Paris Cedex 15, France; CEA, Division of Immuno-Virology, iMETI/DSV, 18 Route du Panorama, 92265 Fontenay-aux-Roses, France.
| | - Asier Sáez-Cirión
- Unité de Régulation des Infections Rétrovirales, Institut Pasteur, 25-28 rue du Dr Roux, 75724 Paris Cedex 15, France.
| |
Collapse
|
7
|
Shytaj IL, Savarino A. A cure for AIDS: a matter of timing? Retrovirology 2013; 10:145. [PMID: 24267982 PMCID: PMC3842794 DOI: 10.1186/1742-4690-10-145] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2013] [Accepted: 11/12/2013] [Indexed: 01/08/2023] Open
Abstract
Despite the huge clinical success of antiretroviral therapy, several factors such as side effects, requirement of life-long adherence, high cost, incomplete access to therapies and development of drug resistance make the quest for an ultimate cure of HIV/AIDS a worldwide priority of biomedical research. In this respect, several sterilizing or functional cures have been reported in the last years in both non-human primates and humans. This review provides a summary of the main results achieved so far, outlining their strengths as well as their limitations. A synthetic interpretation of these results could be pivotal in order to develop an effective and widely available cure.
Collapse
Affiliation(s)
| | - Andrea Savarino
- Istituto Superiore di Sanità, Viale Regina Elena, 299, Rome 00161, Italy.
| |
Collapse
|
8
|
Bhave S, Elford H, McVoy MA. Ribonucleotide reductase inhibitors hydroxyurea, didox, and trimidox inhibit human cytomegalovirus replication in vitro and synergize with ganciclovir. Antiviral Res 2013; 100:151-8. [PMID: 23933116 DOI: 10.1016/j.antiviral.2013.07.016] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2013] [Revised: 07/15/2013] [Accepted: 07/24/2013] [Indexed: 01/12/2023]
Abstract
Ganciclovir (GCV) is a deoxyguanosine analog that is effective in inhibiting human cytomegalovirus (HCMV) replication. In infected cells GCV is converted to GCV-triphosphate which competes with dGTP for incorporation into the growing DNA strand by the viral DNA polymerase. Incorporated GCV promotes chain termination as it is an inefficient substrate for elongation. Because viral DNA synthesis also relies on cellular ribonucleotide reductase (RR) to synthesize deoxynucleotides, RR inhibitors are predicted to inhibit HCMV replication. Moreover, as dGTP competes with GCV-triphosphate for incorporation, RR inhibitors may also synergize with GCV by reducing intracellular dGTP levels and there by promoting increased GCV-triphosphate utilization by DNA polymerase. To investigate potential of RR inhibitors as anti-HCMV agents both alone and in combination with GCV, HCMV-inhibitory activities of three RR inhibitors, hydroxyurea, didox, and trimidox, were determined. In both spread inhibition and yield reduction assays RR inhibitors had modest anti-HCMV activity with 50% inhibitory concentrations ranging from 36±1.7 to 221±52μM. However, all three showed significant synergy with GCV at concentrations below their 50% inhibitory and 50% toxic concentrations. These results suggest that combining GCV with relatively low doses of RR inhibitors could significantly potentiate the anti-HCMV activity of GCV in vivo and could improve clinical response to therapy.
Collapse
Affiliation(s)
- Sukhada Bhave
- Department of Pediatrics, Virginia Commonwealth University School of Medicine, Richmond, VA 23298, USA
| | | | | |
Collapse
|
9
|
Kovacic P. Hydroxyurea (therapeutics and mechanism): Metabolism, carbamoyl nitroso, nitroxyl, radicals, cell signaling and clinical applications. Med Hypotheses 2011; 76:24-31. [DOI: 10.1016/j.mehy.2010.08.023] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2010] [Revised: 08/03/2010] [Accepted: 08/08/2010] [Indexed: 10/19/2022]
|
10
|
Sassi H, Bachir D, Habibi A, Astier A, Galactéros F, Hulin A. No effect of CYP450 and P-glycoprotein on hydroxyurea in vitro metabolism. Fundam Clin Pharmacol 2010; 24:83-90. [DOI: 10.1111/j.1472-8206.2009.00723.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
11
|
Psoriasis in patients with HIV infection: from the medical board of the National Psoriasis Foundation. J Am Acad Dermatol 2009; 62:291-9. [PMID: 19646777 DOI: 10.1016/j.jaad.2009.03.047] [Citation(s) in RCA: 81] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2008] [Revised: 03/26/2009] [Accepted: 03/30/2009] [Indexed: 11/21/2022]
Abstract
BACKGROUND Patients with psoriasis and HIV infection often present with more severe and treatment-refractory cutaneous disease. In addition, many of these patients have significant psoriatic arthritis. Many effective drugs for psoriasis and psoriatic arthritis are immunosuppressive. Therefore, therapy for the HIV-infected patient is more challenging, requiring both careful consideration of the potential risks and benefits of treatment and more fastidious monitoring for potential adverse events. OBJECTIVE A task force of the National Psoriasis Foundation Medical Board was convened to evaluate treatment options. Our aim was to arrive at a consensus on therapy for psoriasis in patients with HIV. METHODS A MEDLINE search of the terms "psoriasis," "psoriatic arthritis," "human immunodeficiency virus (HIV)," and "HIV skin diseases" was performed and literature relevant to HIV-associated psoriasis and the treatment of HIV-associated psoriasis were reviewed. RESULTS Based on a review of the literature, 29 reports were included as evidence in this review. Topical therapy is the first-line recommended treatment for mild to moderate disease. For moderate to severe disease, phototherapy and antiretrovirals are the recommended first-line therapeutic agents. Oral retinoids may be used as second-line treatment. For more refractory, severe disease, cautious use of cyclosporine, methotrexate, hydroxyurea, and tumor necrosis factor-alpha inhibitors may also be considered. LIMITATIONS There are no randomized, placebo-controlled trials evaluating the therapeutic efficacy or safety of treatments for patients with HIV-associated psoriasis; consequently, the evidence supporting this review consists mainly of case reports or case series. CONCLUSIONS HIV-associated psoriasis is often refractory to traditional treatments. Treatment is challenging and requires careful consideration and should be tailored to patients based on disease severity and the input from an infectious disease specialist. Close monitoring for potential adverse events is necessary.
Collapse
|
12
|
García M, Yu XF, Griffin DE, Moss WJ. Measles virus inhibits human immunodeficiency virus type 1 reverse transcription and replication by blocking cell-cycle progression of CD4+ T lymphocytes. J Gen Virol 2008; 89:984-993. [PMID: 18343840 DOI: 10.1099/vir.0.83601-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Acute measles virus (MV) infection results in a decrease in plasma human immunodeficiency virus type 1 (HIV-1) RNA levels in co-infected children. An in vitro peripheral blood mononuclear cell (PBMC) culture system was used to assess the mechanisms by which MV blocks HIV-1 replication. MV inhibited proliferation of CD4(+) T lymphocytes, the target cell for HIV-1 replication. In the presence of MV, cells did not progress to G(1b) and S phases, steps critical for the completion of HIV-1 reverse transcription and productive replication. This block in cell-cycle progression was characterized by an increased proportion of CD4(+) and HIV-1-infected cells retained in the parental generation in PBMCs co-cultured with MV and HIV-1, and decreased levels of cyclins and RNA synthesis. Early HIV-1 replication was also inhibited in the presence of MV, as measured by reduced expression of a luciferase reporter gene and lower levels of both early (LTR) and late (LTR-gag) DNA intermediates of HIV-1 reverse transcription in the presence of CCR5-tropic HIV-1. The effects of MV on lymphoproliferation and p24 antigen production were reproduced by n-butyrate and hydroxyurea, drugs that block the cell cycle in G(1a) and G(1)/S, respectively. It was concluded that MV inhibits HIV-1 productive replication in part by blocking the proliferation of CD4(+) T lymphocytes.
Collapse
Affiliation(s)
- Mayra García
- Cellular and Molecular Medicine, School of Medicine; Johns Hopkins University, Baltimore, MD 21205, USA
- W. Harry Feinstone Department of Molecular Microbiology and Immunology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Xiao-Fang Yu
- W. Harry Feinstone Department of Molecular Microbiology and Immunology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Diane E Griffin
- W. Harry Feinstone Department of Molecular Microbiology and Immunology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD 21205, USA
| | - William J Moss
- Department of Epidemiology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD 21205, USA
- W. Harry Feinstone Department of Molecular Microbiology and Immunology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD 21205, USA
| |
Collapse
|
13
|
Nayab SN, Jones FH, Olsen I. Modulation of the human bone cell cycle by calcium ion-implantation of titanium. Biomaterials 2007; 28:38-44. [PMID: 16952393 DOI: 10.1016/j.biomaterials.2006.08.032] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2006] [Accepted: 08/16/2006] [Indexed: 11/18/2022]
Abstract
Ca ion implantation of Ti surfaces has previously been reported to enhances osseointegration in vivo. Although the mechanisms underlying the response of bone cells to these novel surfaces still remain unclear, it is possible that Ca ion-implanted Ti (Ca-Ti) may influence the growth of new bone by modulating the progression of the cell cycle. In the present study we have, therefore, examined the precise effects of Ca ion-implantation of Ti on the bone-like MG-63 cell line in vitro. The results of flow cytometry analysis showed that this surface markedly enhanced the proportion of cells which expressed Ki-67, a cell proliferation-associated nuclear antigen, compared with cells grown on the non-implanted Ti (control) surface. In addition, cultures grown on Ca-Ti and synchronized at the G1/S boundary by hydroxyurea more rapidly re-entered and progressed through the S and G2/M phases of the cell cycle than their counterparts on Ti. Ca ion-implantation also significantly increased the numbers of mitotic cells. These results thus show that alteration of the surface chemistry of Ti by high-energy implantation with Ca ion was able to substantially modulate the progression of the bone cell cycle, and suggest a possible means of enhancing the response of bone cells to implant materials.
Collapse
Affiliation(s)
- Saima N Nayab
- Division of Biomaterials and Tissue Engineering, University College London, Eastman Dental Institute, 256 Gray's Inn Road, London WC1X 8LD, UK
| | | | | |
Collapse
|
14
|
Kim HN, Harrington RD. Antiretroviral therapy: a primer for dermatologists. Dermatol Clin 2006; 24:537-47, vii. [PMID: 17010782 DOI: 10.1016/j.det.2006.06.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Combination antiretroviral therapy (ART) has transformed the care of individuals who have HIV infection. Effective ART has resulted in dramatic reductions in mortality, hospitalization rates, and the development of AIDS-defining illnesses. This article discusses the variety of agents that can comprise an effective ART regimen, focusing on the basic principles of ART, the indications for initiating ART in treatment-naive individuals who have established HIV infection, and the challenges associated with the use of antiretroviral medications.
Collapse
Affiliation(s)
- H Nina Kim
- Division of Allergy and Infectious Diseases, University of Washington School of Medicine, 325 Ninth Avenue, Seattle WA 98104, USA.
| | | |
Collapse
|
15
|
Back DJ, Burger DM, Flexner CW, Gerber JG. The pharmacology of antiretroviral nucleoside and nucleotide reverse transcriptase inhibitors: implications for once-daily dosing. J Acquir Immune Defic Syndr 2005; 39 Suppl 1:S1-23, quiz S24-25. [PMID: 15990598 DOI: 10.1097/01.qai.0000168882.67942.3f] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The trend toward once-daily dosing in HIV antiretroviral therapy is based on the association between adherence, treatment outcome, and patient preferences. Patients prefer simpler treatments, fewer pills, less frequent dosing, and no food restrictions. When a regimen meets a patient's preferences, the patient is more likely to be adherent, and with good adherence, the regimen is more likely to be effective. Nucleoside/nucleotide reverse transcriptase inhibitors (NRTIs) have been a prime focus for developing once-daily therapies primarily because they form the backbone of most current regimens. Within the NRTI class, however, drugs differ in their pharmacokinetic properties, such as plasma and intracellular half-lives, and thus in their suitability for once-daily dosing. For example, newer NRTIs, such as tenofovir and emtricitabine, combine longer plasma half-lives with longer intracellular half-lives, prolonging exposure and the period of pharmacologic activity. Of equal importance, the clinical impact of systemic and intracellular interactions between concomitant drugs defines which once-daily drugs may be combined in once-daily regimens. To construct simplified and effective therapies for individual patients, clinicians require an understanding of the plasma and intracellular pharmacokinetic properties of NRTIs and how these properties determine a drug's appropriateness for once-daily dosing and placement within a once-daily regimen.
Collapse
Affiliation(s)
- David J Back
- Department of Pharmacology, University of Liverpool, Liverpool, UK
| | | | | | | |
Collapse
|
16
|
Wakisaka N, Yoshizaki T, Raab-Traub N, Pagano JS. Ribonucleotide reductase inhibitors enhance cidofovir-induced apoptosis in EBV-positive nasopharyngeal carcinoma xenografts. Int J Cancer 2005; 116:640-5. [PMID: 15818619 DOI: 10.1002/ijc.21096] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
In nasopharyngeal carcinoma (NPC), Epstein-Barr virus (EBV) infection is mainly latent, and the tumor cells contain episomal viral DNA. We have shown that the acyclic nucleoside phosphonate analog, cidofovir [(S)-1-(3-hydroxy-2-(phosphonylmethoxypropyl))cytosine] (HPMPC), inhibits growth of NPC xenografts in nude mice by causing apoptosis. The ribonucleotide reductase (RR) inhibitors, hydroxyurea and didox (3,4-dihydroxybenzohydroxamic acid), have been demonstrated to inhibit neoplastic growth and are used as antiviral and anticancer agents. Here we show that RR inhibitors enhance the antitumor effect of cidofovir in EBV-transformed epithelial cells. MTT assays indicate that hydroxyurea and didox enhance cidofovir-induced cell toxicity in NPC-KT cells, an EBV-positive epithelial cell line derived from NPC. The effect is due to enhancement of apoptosis through the caspase cascade as shown by pronounced cleavage of poly(ADP-ribose) polymerase. Finally, hydroxyurea strikingly enhanced the cidofovir-induced growth-inhibitory effect on NPC grown in athymic mice. The results suggest that RR inhibitors should enhance the antitumor effect of acyclic nucleoside phosphonate analogs on NPC.
Collapse
Affiliation(s)
- Naohiro Wakisaka
- Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, NC 27599, USA
| | | | | | | |
Collapse
|
17
|
Gazzard B. British HIV Association (BHIVA) guidelines for the treatment of HIV-infected adults with antiretroviral therapy (2005). HIV Med 2005; 6 Suppl 2:1-61. [PMID: 16011536 DOI: 10.1111/j.1468-1293.2005.0311b.x] [Citation(s) in RCA: 96] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- B Gazzard
- Chelsea and Westimnster Hospital, London, UK.
| |
Collapse
|
18
|
Abstract
HIV-1 and other retroviruses exhibit mutation rates that are 1,000,000-fold greater than their host organisms. Error-prone viral replication may place retroviruses and other RNA viruses near the threshold of "error catastrophe" or extinction due to an intolerable load of deleterious mutations. Strategies designed to drive viruses to error catastrophe have been applied to HIV-1 and a number of RNA viruses. Here, we review the concept of extinguishing HIV infection by "lethal mutagenesis" and consider the utility of this new approach in combination with conventional antiretroviral strategies.
Collapse
Affiliation(s)
- Robert A Smith
- Department of Pathology, University of Washington, Seattle, WA 18195, USA.
| | | | | |
Collapse
|
19
|
Frank I, Bosch RJ, Fiscus S, Valentine F, Flexner C, Segal Y, Ruan P, Gulick R, Wood K, Estep S, Fox L, Nevin T, Stevens M, Eron JJ. Activity, safety, and immunological effects of hydroxyurea added to didanosine in antiretroviral-naive and experienced HIV type 1-infected subjects: a randomized, placebo-controlled trial, ACTG 307. AIDS Res Hum Retroviruses 2004; 20:916-26. [PMID: 15597521 DOI: 10.1089/aid.2004.20.916] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
We performed a 24-week, placebo-controlled, comparative trial of hydroxyurea (HU) monotherapy, didanosine(ddI) monotherapy, and the combination of ddI plus HU administered as 1000 mg qd or 1500 mg qd in antiretroviral-naive and experienced subjects with CD4+ lymphocyte counts of 200-700 cells/mm3. Enrollment included 134 subjects. HU enhanced the antiviral activity of ddI by 1.0 log10 copies/ml after 8 weeks of therapy, with sustained responses over 24 weeks. HU alone over 4 weeks had no effect. Lamivudine resistance had little impact on antiretroviral activity when examined across treatment arms. Increases in absolute CD4+ T cell counts, but not CD4+ T cell percentages, were less in subjects who received HU compared to ddI monotherapy, and lymphoproliferative responses to antigenic and mitogenic stimuli were not altered. Subjects who received HU 1500 mg were more likely to experience dose-limiting hematological toxicities compared to those who received 1000 mg, without any additional antiviral benefit. HU may continue to have a role as a component of HIV therapy.
Collapse
|
20
|
British HIV Association (BHIVA) guidelines for the treatment of HIV-infected adults with antiretroviral therapy. HIV Med 2003. [DOI: 10.1046/j.1468-1293.4.s1.3.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
|
21
|
Dogruel M, Gibbs JE, Thomas SA. Hydroxyurea transport across the blood-brain and blood-cerebrospinal fluid barriers of the guinea-pig. J Neurochem 2003; 87:76-84. [PMID: 12969254 DOI: 10.1046/j.1471-4159.2003.01968.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Hydroxyurea is used in the treatment of HIV infection in combination with nucleoside analogues, 2'3'-didehydro-3'deoxythymidine (D4T), 2'3'-dideoxyinosine or abacavir. It is distributed into human CSF and is transported from the CSF to sub-ependymal brain sites, but its movement into the brain directly from the blood has not been studied. This study addressed this by a brain perfusion technique in anaesthetized guinea-pigs. The carotid arteries were perfused with an artificial plasma containing [14C]hydroxyurea (1.6 microm) and a vascular marker, [3H]mannitol (4.6 nm). Brain uptake of [14C]hydroxyurea (8.0 +/- 0.9%) was greater than [3H]mannitol (2.4 +/- 0.2%; 20-min perfusion, n = 8). CSF uptake of [14C]hydroxyurea (5.6 +/- 1.5%) was also greater than [3H]mannitol (0.9 +/- 0.3%; n = 4). Brain uptake of [14C]hydroxyurea was increased by 200 microm hydroxyurea, 90 microm D4T, 350 microm probenecid, 25 microm digoxin, but not by 120 microm hydroxyurea, 16.5-50 microm D4T, 90 microm 2'3'-dideoxyinosine or 90 microm abacavir. [14C]Hydroxyurea distribution to the CSF, choroid plexus and pituitary gland remained unaffected by all these drugs. The metabolic half-life of hydroxyurea was > 15 h in brain and plasma. Results indicate that intact hydroxyurea can cross the brain barriers, but is removed from the brain by probenecid- and digoxin-sensitive transport mechanisms at the blood-brain barrier, which are also affected by D4T. These sensitivities implicate an organic anion transporter (probably organic anion transporting polypeptide 2) and possibly p-glycoprotein in the brain distribution of hydroxyurea and D4T.
Collapse
Affiliation(s)
- M Dogruel
- Centre for Neuroscience Research, Guy's, King's and St. Thomas School of Biomedical Science, King's College London, London, UK
| | | | | |
Collapse
|
22
|
Shirlaw PJ, Chikte U, MacPhail L, Schmidt-Westhausen A, Croser D, Reichart P. Oral and dental care and treatment protocols for the management of HIV-infected patients. Oral Dis 2002; 8 Suppl 2:136-43. [PMID: 12164647 DOI: 10.1034/j.1601-0825.2002.00025.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
This paper describes the workings of the workshop dedicated to oral and dental care and treatment protocols for the management of HIV-infected patients. The questions addressed were: 1) What are the current ethical issues in dental care of HIV patients, do they need to be addressed? 2) Do we need to modify the dental care we give HIV-positive patients? 3) When is it necessary to give antibiotic prophylaxis to HIV-positive patients? 4) What is the evidence for the effective treatment of oral lesions associated with HIV? 5) What is the most successful palliative treatment for KS? 6) Can we provide clinical treatment that has a scientific basis rather being trial based? 7) Is ddI + hydroxy-urea an effective African alternative to HAART? 8) What is the influence of protease inhibitors and HAART on the excretion of HIV in saliva? 9) What is the effect of anti-HIV therapy on the oral mucosa and oral health? This workshop did not fully cover the issue of ddI and hydroxy-urea as an alternative HIV therapy as this was considered to be the remit of general physicians caring for patients with HIV and AIDS rather than that of oral health care workers.
Collapse
Affiliation(s)
- P J Shirlaw
- Department of Oral Medicine and Pathology, Guy's Hospital, London, UK.
| | | | | | | | | | | |
Collapse
|
23
|
Katz RA, Greger JG, Darby K, Boimel P, Rall GF, Skalka AM. Transduction of interphase cells by avian sarcoma virus. J Virol 2002; 76:5422-34. [PMID: 11991971 PMCID: PMC137034 DOI: 10.1128/jvi.76.11.5422-5434.2002] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
It has been generally believed that oncoretroviruses are dependent on mitosis for efficient nuclear entry of viral DNA. We previously identified a nuclear localization signal in the integrase protein of an oncoretrovirus, avian sarcoma virus (ASV), suggesting an active import mechanism for the integrase-DNA complex (G. Kukolj, R. A. Katz, and A. M. Skalka, Gene 223:157-163, 1998). Here, we have evaluated the requirement for mitosis in nuclear import and integration of ASV DNA. Using a modified ASV encoding a murine leukemia virus amphotropic env gene and a green fluorescent protein (GFP) reporter gene, DNA nuclear import was measured in cell cycle-arrested avian (DF-1) as well as human (HeLa) and mouse cells. The results showed efficient accumulation of nuclear forms of ASV DNA in gamma-irradiation-arrested cells. Efficient transduction of a GFP reporter gene was also observed after infection of cells that were arrested with gamma-irradiation, mitomycin C, nocodazole, or aphidicolin, confirming that nuclear import and integration of ASV DNA can occur in the absence of mitosis. By monitoring GFP expression in individual cells, we also obtained evidence for nuclear import of viral DNA during interphase in cycling cells. Lastly, we observed that ASV can transduce postmitotic mouse neurons. These results support an active nuclear import mechanism for the oncoretrovirus ASV and suggest that this mechanism can operate in both nondividing and dividing cells.
Collapse
Affiliation(s)
- Richard A Katz
- Institute for Cancer Research, Fox Chase Cancer Center, Philadelphia, Pennsylvania 19111, USA.
| | | | | | | | | | | |
Collapse
|
24
|
Abstract
New HIV treatment strategies are needed. Over the past year, substantial progress has been made in the development of new antiretroviral agents, although the journey from drug discovery to wide clinical use is completed by only a small number of medications. Strategies to enhance immune control and either discontinue or decrease the need for prolonged HAART are under study. The promising preliminary results in very early PHI are in contrast with the minor successes in chronic infection.
Collapse
Affiliation(s)
- J J Eron
- Infectious Diseases Division, 547 Burnett-Womack, CB #7030, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-7030, USA.
| | | |
Collapse
|
25
|
Schwartz EJ, Neumann AU, Teixeira AV, Bruggeman LA, Rappaport J, Perelson AS, Klotman PE. Effect of target cell availability on HIV-1 production in vitro. AIDS 2002; 16:341-5. [PMID: 11834944 DOI: 10.1097/00002030-200202150-00004] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE The recovery of CD4 target cells following antiretroviral therapy may facilitate virus production and escape from antiretroviral suppression. To address this hypothesis, we directly examined whether the CD4 target cell number increases viral production in the presence of suboptimal therapy. DESIGN The effect of the CD4 T cell number on HIV-1 replication with a suboptimal dose of zidovudine was studied in vitro. METHODS Varying numbers of CD4 T cells were infected with HIV-1 and treated with 1 nM zidovudine. Virus production was measured by p24 antigen capture enzyme-linked immunosorbent assay. Partial sequencing of HIV-1 pol was performed to assess zidovudine-resistant mutations. RESULTS Wild type virus production was found to increase eightfold in cultures with 100 x 10(4) cells compared with cultures with 10 x 10(4) cells. The IC90 of zidovudine was 4 logs higher in cultures with 16 x 10(4) cells compared with cultures with 1 x 10(4) cells. No zidovudine-resistant mutations were found. CONCLUSION Target cell availability may play a direct role in wild type HIV-1 resurgence following therapy.
Collapse
Affiliation(s)
- Elissa J Schwartz
- Division of Nephrology, Mount Sinai Medical Center, One Gustave L. Levy Place, New York, NY 10029, USA.
| | | | | | | | | | | | | |
Collapse
|
26
|
Hoggard PG, Back DJ. Intracellular pharmacology of nucleoside analogues and protease inhibitors: role of transporter molecules. Curr Opin Infect Dis 2002; 15:3-8. [PMID: 11964899 DOI: 10.1097/00001432-200202000-00002] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Antiretroviral agents target HIV replication within infected cells. It is therefore important to focus on the pharmacology of these drugs at their site of action rather than just in plasma. Activation of nucleoside analogues to a triphosphate is essential for antiretroviral activity. Following activation, by intracellular kinases, drug triphosphates compete with endogenous triphosphates for HIV reverse transcriptase. Methodologies to measure triphosphates in peripheral blood mononuclear cells from HIV patients have been described. This has allowed investigation of once-daily dosing regimens, drug interactions, modulation of intracellular activation and the bypassing of initial phosphorylation steps. Drug accumulation within a cell is a balance between influx and efflux. There is a growing body of evidence indicating that transport proteins are vitally important in regulating intracellular concentrations of antiretroviral drugs. Allelic variants, inhibition (or induction) are all potentially critical determinants of active drug present in the cell. It is hoped that understanding the intracellular pharmacology will improve long-term therapy and reduce the likelihood of cellular resistance in therapeutic failure.
Collapse
Affiliation(s)
- Patrick G Hoggard
- Department of Pharmacology and Therapeutics, New Medical Building, University of Liverpool, Ashton Street, Liverpool L69 3GE, UK
| | | |
Collapse
|
27
|
Sakano K, Oikawa S, Hasegawa K, Kawanishi S. Hydroxyurea induces site-specific DNA damage via formation of hydrogen peroxide and nitric oxide. Jpn J Cancer Res 2001; 92:1166-74. [PMID: 11714440 PMCID: PMC5926660 DOI: 10.1111/j.1349-7006.2001.tb02136.x] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Hydroxyurea is a chemotherapeutic agent used for the treatment of myeloproliferative disorders (MPD) and solid tumors. The mutagenic and carcinogenic potential of hydroxyurea has not been established, although hydroxyurea has been associated with an increased risk of leukemia in MPD patients. To clarify whether hydroxyurea has potential carcinogenicity, we examined site-specific DNA damage induced by hydroxyurea using (32)P-5'-end-labeled DNA fragments obtained from the human p53 and p16 tumor suppressor genes and the c-Ha-ras-1 protooncogene. Hydroxyurea caused Cu(II)-mediated DNA damage especially at thymine and cytosine residues. NADH efficiently enhanced hydroxyurea-induced DNA damage. The DNA damage was almost entirely inhibited by catalase and bathocuproine, a Cu(I)-specific chelator, suggesting the involvement of hydrogen peroxide (H(2)O(2)) and Cu(I). Typical free hydroxyl radical scavengers did not inhibit DNA damage by hydroxyurea, but methional did. These results suggest that crypto-hydroxyl radicals such as Cu(I)-hydroperoxo complex (Cu(I)-OOH) cause DNA damage. Formation of 8-hydroxy-2'-deoxyguanosine (8-OHdG) was induced by hydroxyurea in the presence of Cu(II). An electron spin resonance spectroscopic study using N-(dithiocarboxy)sarcosine as a nitric oxide (NO)-trapping reagent demonstrated that NO was generated from hydroxyurea in the presence and absence of catalase. In addition, the generation of formamide was detected by both gas chromatography-mass spectrometry (GC-MS) and time-of-flight-mass spectrometry (TOF-MS). A high concentration of hydroxyurea induced depurination at DNA bases in an H(2)O(2)-independent manner, and endonuclease IV treatment led to chain cleavages. These results suggest that hydroxyurea could induce base oxidation as the major pathway of DNA modification and depurination as a minor pathway. Therefore, it is considered that DNA damage by hydroxyurea participates in not only anti-cancer activity, but also carcinogenesis.
Collapse
Affiliation(s)
- K Sakano
- Department of Hygiene, Mie University School of Medicine, Tsu, Mie 514-8507
| | | | | | | |
Collapse
|
28
|
British HIV Association (BHIVA) guidelines for the treatment of HIV-infected adults with antiretroviral therapy. HIV Med 2001; 2:276-313. [PMID: 11737410 DOI: 10.1046/j.1464-2662.2001.00083.x] [Citation(s) in RCA: 100] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
|