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Zhang L, Ramratnam B, Tenner-Racz K, He Y, Vesanen M, Lewin S, Talal A, Racz P, Perelson AS, Korber BT, Markowitz M, Ho DD. Quantifying residual HIV-1 replication in patients receiving combination antiretroviral therapy. N Engl J Med 1999; 340:1605-13. [PMID: 10341272 DOI: 10.1056/nejm199905273402101] [Citation(s) in RCA: 619] [Impact Index Per Article: 23.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
BACKGROUND In patients infected with human immunodeficiency virus type 1 (HIV-1), combination antiretroviral therapy can result in sustained suppression of plasma levels of the virus. However, replication-competent virus can still be recovered from latently infected resting memory CD4 lymphocytes; this finding raises serious doubts about whether antiviral treatment can eradicate HIV-1. METHODS We looked for evidence of residual HIV-1 replication in eight patients who began treatment soon after infection and in whom plasma levels of HIV-1 RNA were undetectable after two to three years of antiretroviral therapy. We examined whether there had been changes over time in HIV-1 proviral sequences in peripheral-blood mononuclear cells, which would indicate residual viral replication. We also performed in situ hybridization studies on tissues from one patient to identify cells actively expressing HIV-1 RNA. We estimated the rate of decrease of latent, replication-competent HIV-1 in resting CD4 lymphocytes on the basis of the decrease in the numbers of proviral sequences identified during primary infection and direct sequential measurements of the size of the latent reservoir. RESULTS Six of the eight patients had no significant variations in proviral sequences during treatment. However, in two patients there was sequence evolution but no evidence of drug-resistant viral genotypes. In one patient, extensive in situ studies provided additional evidence of persistent viral replication in lymphoid tissues. Using two independent approaches, we estimated that the half-life of the latent, replication-competent virus in resting CD4 lymphocytes was approximately six months. CONCLUSIONS These findings suggest that combination antiretroviral regimens suppress HIV-1 replication in some but not all patients. Given the half-life of latently infected CD4 lymphocytes of about six months, it may require many years of effective antiretroviral treatment to eliminate this reservoir of HIV-1.
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Clinical Trial |
26 |
619 |
2
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Logvinoff C, Major ME, Oldach D, Heyward S, Talal A, Balfe P, Feinstone SM, Alter H, Rice CM, McKeating JA. Neutralizing antibody response during acute and chronic hepatitis C virus infection. Proc Natl Acad Sci U S A 2004; 101:10149-54. [PMID: 15220475 PMCID: PMC454180 DOI: 10.1073/pnas.0403519101] [Citation(s) in RCA: 328] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Little is known about the role of Abs in determining the outcome of hepatitis C virus (HCV) infection. By using infectious retroviral pseudotypes bearing HCV glycoproteins, we measured neutralizing Ab (nAb) responses during acute and chronic HCV infection. In seven acutely infected health care workers, only two developed a nAb response that failed to associate with viral clearance. In contrast, the majority of chronically infected patients had nAbs. To determine the kinetics of strain-specific and crossreactive nAb emergence, we studied patient H, the source of the prototype genotype 1a H77 HCV strain. An early weak nAb response, specific for the autologous virus, was detected at seroconversion. However, neutralization of heterologous viruses was detected only between 33 and 111 weeks of infection. We also examined the development of nAbs in 10 chimpanzees infected with H77 clonal virus. No nAb responses were detected in three animals that cleared virus, whereas strain-specific nAbs were detected in six of the seven chronically infected animals after approximately 50 weeks of infection. The delayed appearance of high titer crossreactive nAbs in chronically infected patients suggests that selective mechanism(s) may operate to prevent the appearance of these Abs during acute infection. The long-term persistence of these nAbs in chronically infected patients may regulate viral replication.
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21 |
328 |
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Zhang L, He T, Talal A, Wang G, Frankel SS, Ho DD. In vivo distribution of the human immunodeficiency virus/simian immunodeficiency virus coreceptors: CXCR4, CCR3, and CCR5. J Virol 1998; 72:5035-45. [PMID: 9573273 PMCID: PMC110066 DOI: 10.1128/jvi.72.6.5035-5045.1998] [Citation(s) in RCA: 143] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
We have evaluated the in vivo distribution of the major human immunodeficiency virus/simian immunodeficiency virus (HIV/SIV) coreceptors, CXCR4, CCR3, and CCR5, in both rhesus macaques and humans. T lymphocytes and macrophages in both lymphoid and nonlymphoid tissues are the major cell populations expressing HIV/SIV coreceptors, reaffirming that these cells are the major targets of HIV/SIV infection in vivo. In lymphoid tissues such as the lymph node and the thymus, approximately 1 to 10% of the T lymphocytes and macrophages are coreceptor positive. However, coreceptor expression was not detected on follicular dendritic cells (FDC) in lymph nodes, suggesting that the ability of FDC to trap extracellular virions is unlikely to be mediated by a coreceptor-specific mechanism. In the thymus, a large number of immature and mature T lymphocytes express CXCR4, which may render these cells susceptible to infection by syncytium-inducing viral variants that use this coreceptor for entry. In addition, various degrees of coreceptor expression are found among different tissues and also among different cells within the same tissues. Coreceptor-positive cells are more frequently identified in the colon than in the rectum and more frequently identified in the cervix than in the vagina, suggesting that the expression levels of coreceptors are differentially regulated at different anatomic sites. Furthermore, extremely high levels of CXCR4 and CCR3 expression are found on the neurons from both the central and peripheral nervous systems. These findings may be helpful in understanding certain aspects of HIV and SIV pathogenesis and transmission.
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143 |
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Markowitz M, Vesanen M, Tenner-Racz K, Cao Y, Binley JM, Talal A, Hurley A, Jin X, Chaudhry MR, Yaman M, Frankel S, Heath-Chiozzi M, Leonard JM, Moore JP, Racz P, Nixon DF, Ho DD, J X. The effect of commencing combination antiretroviral therapy soon after human immunodeficiency virus type 1 infection on viral replication and antiviral immune responses. J Infect Dis 1999; 179:527-37. [PMID: 9952358 DOI: 10.1086/314628] [Citation(s) in RCA: 140] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
Twelve subjects were treated with zidovudine, lamivudine, and ritonavir within 90 days of onset of symptoms of acute infection to determine whether human immunodeficiency virus type 1 (HIV-1) infection could be eradicated from an infected host. In adherent subjects, with or without modifications due to intolerance, viral replication was suppressed during the 24-month treatment period. Durable suppression reduced levels of HIV-1-specific antibodies and cytotoxic T lymphocyte responses in selected subjects. Proviral DNA in mononuclear cells uniformly persisted. The persistence of HIV-1 RNA expression in lymphoid tissues and peripheral blood mononuclear cells suggests that elimination of this residual pool of virus should be achieved before considering adjustments in antiretroviral therapeutic regimens. In addition, given the reduction in levels of virus-specific immune responses, it would seem prudent to consider enhancing these responses using vaccine strategies prior to the withdrawal of antiviral therapy.
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140 |
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Poles MA, Barsoum S, Yu W, Yu J, Sun P, Daly J, He T, Mehandru S, Talal A, Markowitz M, Hurley A, Ho D, Zhang L. Human immunodeficiency virus type 1 induces persistent changes in mucosal and blood gammadelta T cells despite suppressive therapy. J Virol 2003; 77:10456-67. [PMID: 12970431 PMCID: PMC228518 DOI: 10.1128/jvi.77.19.10456-10467.2003] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Gammadelta T cells are primarily found in the gastrointestinal mucosa and play an important role in the first line of defense against viral, bacterial, and fungal pathogens. We sought to examine the impact of human immunodeficiency virus type 1 (HIV-1) infection on mucosal as well as peripheral blood gammadelta T-cell populations. Our results demonstrate that HIV-1 infection is associated with significant expansion of Vdelta1 and contraction of Vdelta2 cell populations in both the mucosa and peripheral blood. Such changes were observed during acute HIV-1 infection and persisted throughout the chronic phase, without apparent reversion after treatment with highly active antiretroviral therapy (HAART). Despite an increase in the expression of CCR9 and CD103 mucosal homing receptors on peripheral blood gammadelta T cells in infected individuals, mucosal and peripheral blood gammadelta T cells appeared to be distinct populations, as reflected by distinct CDR3 length polymorphisms and sequences in the two compartments. Although the underlying mechanism responsible for triggering the expansion of Vdelta1 gammadelta T cells remains unknown, HIV-1 infection appears to have a dramatic impact on gammadelta T cells, which could have important implications for HIV-1 pathogenesis.
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22 |
60 |
6
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Hughes FJ, Ghuman M, Talal A. Periodontal regeneration: a challenge for the tissue engineer? Proc Inst Mech Eng H 2010; 224:1345-58. [PMID: 21287824 DOI: 10.1243/09544119jeim820] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Periodontitis affects around 15 per cent of human adult populations. While periodontal treatment aimed at removing the bacterial cause of the disease is generally very successful, the ability predictably to regenerate the damaged tissues remains a major unmet objective for new treatment strategies. Existing treatments include the use of space-maintaining barrier membranes (guided tissue regeneration), use of graft materials, and application of bioactive molecules to induce regeneration, but their overall effects are relatively modest and restricted in application. The periodontal ligament is rich in mesenchymal stem cells, and the understanding of the signalling molecules that may regulate their differentation has increased enormously in recent years. Applying these principles for the development of new tissue engineering strategies for periodontal regeneration will require further work to determine the efficacy of current experimental preclinical treatments, including pharmacological application of growth factors such as bone morphogenetic proteins (BMPs) or Wnts, use of autologous stem cell reimplantation strategies, and development of improved biomaterial scaffolds. This article describes the background to this problem, addresses the current status of periodontal regeneration, including the background biology, and discusses the potential for some of these experimental therapies to achieve the goal of clinically predictable periodontal regeneration.
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Review |
15 |
47 |
7
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Zhang L, Rowe L, He T, Chung C, Yu J, Yu W, Talal A, Markowitz M, Ho DD. Compartmentalization of surface envelope glycoprotein of human immunodeficiency virus type 1 during acute and chronic infection. J Virol 2002; 76:9465-73. [PMID: 12186928 PMCID: PMC136436 DOI: 10.1128/jvi.76.18.9465-9473.2002] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Human immunodeficiency virus type 1 is characterized by extensive genetic heterogeneity. Having previously demonstrated that, in the peripheral blood, the initial viral population is more homogeneous than at subsequent stages of infection, we have extended our studies to tissue samples, allowing comparisons between viral populations in peripheral blood and tissues during both the acute and chronic stages of infection. We found that homogeneity in gp120 sequences during the acute infection phase is not just restricted to the peripheral blood but also extends to other tissue compartments. However, in chronically infected individuals, heterogeneous and distinct viral populations were found in different compartments. We therefore conclude that the dominant and homogeneous viral population observed during the acute infection phase is likely to infiltrate lymphoid tissues and form the genetic bases for subsequent diversification. It is therefore likely that the compartmentalization of viral sequences observed in chronically infected patients reflects a gradual diversification of a common dominant viral variant rather than the preferential migration of distinct viral populations to different tissue compartments at the beginning of infection.
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research-article |
23 |
38 |
8
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Parks CG, Moe CL, Rhodes D, Lima A, Barrett L, Tseng F, Baric R, Talal A, Guerrant R. Genomic diversity of "Norwalk like viruses" (NLVs): pediatric infections in a Brazilian shantytown. J Med Virol 1999; 58:426-34. [PMID: 10421412 DOI: 10.1002/(sici)1096-9071(199908)58:4<426::aid-jmv17>3.0.co;2-k] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
"Norwalk-like viruses" (NLVs) are a common cause of epidemic gastroenteritis in adults and children in developed countries. However, little is known about the role of NLVs in endemic pediatric gastroenteritis in developing countries. We sequenced Genogroup I and II NLV reverse transcription-polymerase chain reaction (RT-PCR) products from an 81-nucleotide region of the viral RNA polymerase gene to examine the molecular epidemiology of NLV infection in children younger than 5 years of age in Forteleza, Ceará, Brazil. NLV-positive PCR products were obtained from stool specimens collected over a 16-month period (1990-1991) from diarrhea cases and controls in a cohort of 120 children in an urban shantytown and from a study in the same city of hospitalized children with persistent diarrhea. Eight unique strains were detected in 15 specimens from 10 cohort children and in two hospital specimens. Nucleotide identity between the strains (5 Genogroup I, 3 Genogroup II) ranged from 63% to 88%. We designated these strains BraV1-8, for Brazil virus 1-8. The degree of genomic diversity of NLV strains we identified in this cohort during a short time period suggests multiple foci of infection within the community. Furthermore, sequence analysis of strains from two children with multiple symptomatic NLV infections indicates that infection with one strain was not protective against subsequent infection with a different strain in the same genogroup. These findings have implications for vaccine development and the prevention of pediatric gastroenteritis in developing countries.
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26 |
33 |
9
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Lake-Bakaar G, Jacobson I, Talal A. B cell activating factor (BAFF) in the natural history of chronic hepatitis C virus liver disease and mixed cryoglobulinaemia. Clin Exp Immunol 2013; 170:231-7. [PMID: 23039894 DOI: 10.1111/j.1365-2249.2012.04653.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
B cell activating factor (BAFF) plays a crucial role in the process of development, maturation and activation of B lymphocytes. Chronic hepatitis C virus (HCV) infection is characterized by multiple B cell disorders. It is a major cause of type II mixed cryoglobulinaemia (MC). We measured serum BAFF levels in several clinical situations to elucidate the potential role of BAFF in chronic HCV infection. We used a commercially available solid phase enzyme-linked immunosorbent assay. We estimated serum BAFF in stored sera from uninfected controls (n = 8), patients with chronic hepatitis B virus infection HBV (n = 5) and chronic HCV infection with (n = 16) and without mixed cryoglobulinaemia (n = 14). In two patients with HCV and MC we correlated BAFF with HCV RNA after pegylated interferon (peg-I). We correlated serum BAFF levels at baseline and at 12 weeks with treatment response: sustained virological response SVR (n = 5), non-responders (n = 6) and relapsers (n = 2). Finally, we estimated BAFF levels after complete depletion of B cells with rituximab in patients with chronic HCV with MC (n = 3). Serum levels of BAFF were increased in chronic HCV with MC, but not in chronic HBV infection, suggesting an association between BAFF and cryoglobulinaemia. Peg-I increased BAFF levels in serum and this paralleled HCV RNA very closely. Serum BAFF levels at week 12 of therapy with peg-I and R were significantly higher in responders than non-responders. Finally, B cell depletion was associated with markedly increased levels of BAFF.
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Journal Article |
12 |
20 |
10
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Rosenberg BR, Freije CA, Imanaka N, Chen ST, Eitson JL, Caron R, Uhl SA, Zeremski M, Talal A, Jacobson IM, Rice CM, Schoggins JW. Genetic Variation at IFNL4 Influences Extrahepatic Interferon-Stimulated Gene Expression in Chronic HCV Patients. J Infect Dis 2019; 217:650-655. [PMID: 29165633 DOI: 10.1093/infdis/jix593] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2017] [Accepted: 11/17/2017] [Indexed: 12/25/2022] Open
Abstract
Polymorphisms at IFNL4 strongly influence spontaneous resolution and interferon therapeutic response in hepatitis C virus (HCV) infection. In chronic HCV, unfavorable alleles are associated with elevated interferon (IFN)-stimulated gene (ISG) expression in the liver, but extrahepatic effects are less well characterized. We used RNA sequencing (RNA-Seq) to examine whether IFNL4 genetic variation (rs368234815) modulates ISG expression in peripheral blood mononuclear cells (PBMC) during chronic HCV infection. ISG expression was elevated in unstimulated PBMC homozygous for the unfavorable ΔG IFNL4 variant; expression following IFN-α stimulation was comparable across genotypes. These findings suggest that lambda interferons may have broader systemic effects during HCV infection.
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Research Support, Non-U.S. Gov't |
6 |
15 |
11
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Talal A, Tanner KE, Billington R, Pearson GJ. Effect of ultrasound on the setting characteristics of glass ionomer cements studied by Fourier transform infrared spectroscopy. JOURNAL OF MATERIALS SCIENCE. MATERIALS IN MEDICINE 2009; 20:405-411. [PMID: 18815732 DOI: 10.1007/s10856-008-3578-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2008] [Accepted: 08/29/2008] [Indexed: 05/26/2023]
Abstract
OBJECTIVE To investigate the effect of ultrasound (US) application, US staring time and US duration on the setting of glass ionomer cement (GIC) by using Attenuated Total Reflectance Fourier Transform Infrared (ATR/FTIR) spectrometer. METHODS Two conventional GICs, Fuji IX Fast and Ketac Molar were studied. US application was started at 30 s or 40 s after mixing and was applied for times between 15 and 55 s on samples of two different thicknesses. The samples were analysed using ATR/FTIR. RESULTS US accelerated the curing process in both cements, US needed to be applied for more than 15 s. Both Fuji IX and Ketac Molar showed increased setting on increasing the US application duration from 15 s to 55 s. Increased setting of the GICs was produced when US application started 40 s after mixing rather than 30 s after mixing. CONCLUSIONS The significant findings of the study include that US application accelerated the setting processes, by accelerating the formation of the acid salts. The salt formation increased with increase time of US application. The effect of application of US to setting GICs is influenced by time of the start of application of the US. The effects appear to material specific, with Ketac Molar showing a greater effect than Fuji IX.
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13 |
12
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Kost RG, Hurley A, Zhang L, Vesanen M, Talal A, Furlan S, Caldwell P, Johnson J, Smiley L, Ho D, Markowitz M. Open-label phase II trial of amprenavir, abacavir, and fixed-dose zidovudine/lamivudine in newly and chronically HIV-1--infected patients. J Acquir Immune Defic Syndr 2001; 26:332-9. [PMID: 11317074 DOI: 10.1097/00126334-200104010-00007] [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
A Phase II clinical trial was designed to evaluate the efficacy and tolerability of twice-daily abacavir, amprenavir, and zidovudine (ZDV)/lamivudine (3TC) in HIV-1-infected study subjects naive to protease inhibitors and 3TC. Plasma and cerebrospinal fluid (CSF) HIV-1 RNA levels and T-cell subsets were measured. In all, 27 newly diagnosed and 12 chronically HIV-1-infected study subjects are included in the analysis. Week 48 plasma HIV-1 RNA levels were <500 copies/ml in 100% of study subjects, and <50 copies/ml in 80% of chronically infected and 100% of newly infected study subjects. The mean change in CD4 was (+)150 cells/microl (newly infected, p <.001), and (+)155 cells/microl (chronically infected, p <.001). At Week 48, evidence of cellular activation persisted in both cohorts. A twice-daily regimen of amprenavir, abacavir, and ZDV/3TC affords potent viral suppression and significant increases in total CD4(+) cells in HIV-1--infected study subjects. Patient intolerance may limit the efficacy of this combination.
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Clinical Trial |
24 |
9 |
13
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14
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Bednasz CJ, Sawyer JR, Martinez A, Rose PG, Sithole SS, Hamilton HR, Kaufman FS, Venuto CS, Ma Q, Talal A, Morse GD. Recent advances in management of the HIV/HCV coinfected patient. Future Virol 2016; 10:981-997. [PMID: 26877758 PMCID: PMC4751983 DOI: 10.2217/fvl.15.64] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Chronic hepatitis C virus (HCV) is a global epidemic, affecting approximately 150 million individuals throughout the world. The implications of HCV infection have been magnified in those who are infected with both HCV and the HIV as liver disease progression, liver failure and liver-related death are increased, particularly in those without well-controlled HIV disease. The development of direct-acting antiviral agents for HCV that allow shorter treatment periods with increased efficacy and decreased adverse events have greatly changed the outlook for HCV-infected individuals. With these advancements, growing treatment options for the coinfected population have also come. This review will address pharmacotherapy issues in the HIV/HCV coinfected population.
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research-article |
9 |
4 |
15
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Shata MT, Shan MM, Tricoche N, Talal A, Perkus M, Prince A. Optimization of recombinant vaccinia-based ELISPOT assay. J Immunol Methods 2004; 283:281-9. [PMID: 14659919 DOI: 10.1016/j.jim.2003.10.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The ELISPOT assay has been considered as one of the most sensitive assays to measure antigen-specific CD8 T cells in vitro. Recently, recombinant vaccinia was successfully used to express internally processed target antigens in host cells in direct ex-vivo ELISPOT assays. However, the background in these assays was relatively elevated, and the risk of killing effector T cells was high. Therefore, we examined in this study an alternative approach where the replication of recombinant vaccinia virus was inhibited by the usage of Cidofovir in vitro. Our data indicate that recombinant vaccinia-infected target cells treated with Cidofovir retained their functional activity and present internally processed antigens more efficiently to T cells than non-treated ones. We also identify the optimum doses of Cidofovir to be in the range of 0.75-0.075 microg/ml. Thus, Cidofovir treatment of the target cells prior to antigen stimulation could be a useful methodology to increase the sensitivity of the ELISPOT assay.
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Research Support, U.S. Gov't, P.H.S. |
21 |
4 |
16
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Eisen GM, Sandler RS, Wurzelmann JI, Ransohoff DF, Talal A. Evaluating risk: a primer for gastroenterologists. Am J Gastroenterol 1995; 90:704-7. [PMID: 7733072] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
OBJECTIVE To review the various types of risk measures and to illustrate how interpretations may vary depending on how risk is presented. METHODS We define different types of risk estimates and provide examples of their use from the recent gastroenterological literature. RESULTS Calculations of absolute risk and the number of patients who must receive treatment to prevent one patient from experiencing a disease state (number needed to treat) provide useful information in assessing the utility of fecal occult blood testing for prevention of colorectal cancer and in estimating small bowel cancer rates for individuals with familial adenomatous polyposis. CONCLUSIONS Measures such as relative risk and the odds ratio are best used in analyzing causality but may not be helpful in guiding clinical decisions. Absolute risk and attributable risk reveal the actual number of cases that can be explained by a given exposure and can thereby measure the impact of a clinical intervention for both the population and the patient. These measures should be the criteria for decision-making.
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Jain P, Sehgal M, Narang R, Ginwala R, Zeremski M, Talal A, Elrod E, Grakoui A, Li QG, Philip R, Khan Z. Host genetic factors and miRNA-linked dendritic cell responses associated with the outcome of treatment response in HIV-1/HCV co-infected individuals. THE JOURNAL OF IMMUNOLOGY 2016. [DOI: 10.4049/jimmunol.196.supp.217.21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Abstract
HIV-1/HCV co-infection is a significant burden on global economy and public health. PEGylated interferon and ribavarin remain the essential components of anti-HCV treatment. We investigated the host genetic and immunological correlates of successful treatment response in conjunction with mechanisms by which PEG-IFN is able to clear the virus in a cohort of HIV-1/HCV co-infected individuals undergoing IFN/RBV treatment. First we demonstrate that functional state of DCs before/during therapy influences the treatment outcome. Upon genotyping IFNL3 polymorphisms rs12979860, rs4803217 and ss469415590, we found rs12979860 to be a better predictor of treatment outcome. Next, we compared the expression of forty-six IFN-stimulated genes prior to and after the treatment and observed that pre-treatment levels of several ISGs were higher in SVRs compared to NRs. In continuation, we identified miRNAs whose expression can be regulated by IFN in periphery. miRNA expression patterns in mDCs and pDCs in response to IFN-α were examined and observed miR-221 downregulation via IFN induced STAT3 inhibition in both. Using in-silico approaches followed by experimental validation, CDKN1C, CD54 and SOCS1 were identified as miR-221 targets. Moreover, miR-221 overexpression in mDCs enhanced their secretion of proinflammatory cytokines IL-6 and TNF-α but reduced the secretion of anti-inflammatory cytokine IL-10. These observations were extended and correlated with those obtained with patients’ PBMCs, hepatocytes and kupffer cells from HCV infected individuals as well as individuals with alcoholic cirrhosis. In summary, these studies demonstrated the role of IFN-α/miR-221 axis in HCV pathogenesis and response to IFN-based treatments.
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Kapadia SN, Zhang H, Gonzalez CJ, Sen B, Franco R, Hutchings K, Wethington E, Talal A, Lloyd A, Dharia A, Wells M, Bao Y, Shapiro MF. Hepatitis C Treatment Initiation Among US Medicaid Enrollees. JAMA Netw Open 2023; 6:e2327326. [PMID: 37540513 PMCID: PMC10403776 DOI: 10.1001/jamanetworkopen.2023.27326] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/23/2023] [Accepted: 06/16/2023] [Indexed: 08/05/2023] Open
Abstract
IMPORTANCE Direct-acting antiviral (DAA) treatment for hepatitis C virus (HCV) infection is highly effective but remains underused. Understanding disparities in the delivery of DAAs is important for HCV elimination planning and designing interventions to promote equitable treatment. OBJECTIVE To examine variations in the receipt of DAA in the 6 months following a new HCV diagnosis. DESIGN, SETTING, AND PARTICIPANTS This retrospective cohort study used national Medicaid claims from 2017 to 2019 from 50 states, Washington DC, and Puerto Rico. Individuals aged 18 to 64 years with a new diagnosis of HCV in 2018 were included. A new diagnosis was defined as a claim for an HCV RNA test followed by an International Statistical Classification of Diseases and Related Health Problems, Tenth Revision (ICD-10) diagnosis code, after a 1-year lookback period. MAIN OUTCOMES AND MEASURES Outcome was receipt of a DAA prescription within 6 months of diagnosis. Logistic regression was used to examine demographic factors and ICD-10-identified comorbidities associated with treatment initiation. RESULTS Among 87 652 individuals, 43 078 (49%) were females, 12 355 (14%) were age 18 to 29 years, 35 181 (40%) age 30 to 49, 51 282 (46%) were non-Hispanic White, and 48 840 (49%) had an injection drug use diagnosis. Of these individuals, 17 927 (20%) received DAAs within 6 months of their first HCV diagnosis. In the regression analyses, male sex was associated with increased treatment initiation (OR, 1.24; 95% CI, 1.16-1.33). Being age 18 to 29 years (OR, 0.65; 95% CI, 0.50-0.85) and injection drug use (OR, 0.84; 95% CI, 0.75-0.94) were associated with decreased treatment initiation. After adjustment for state fixed effects, Asian race (OR, 0.50; 95% CI, 0.40-0.64), American Indian or Alaska Native race (OR, 0.68; 95% CI, 0.55-0.84), and Hispanic ethnicity (OR, 0.81; 95% CI, 0.71-0.93) were associated with decreased treatment initiation. Adjustment for state Medicaid policy did not attenuate the racial or ethnic disparities. CONCLUSIONS In this retrospective cohort study, HCV treatment initiation was low among Medicaid beneficiaries and varied by demographic characteristics and comorbidities. Interventions are needed to increase HCV treatment uptake among Medicaid beneficiaries and to address disparities in treatment among key populations, including younger individuals, females, individuals from minoritized racial and ethnic groups, and people who inject drugs.
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Research Support, N.I.H., Extramural |
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Tsuji BT, Venuto C, Ma Q, Difrancesco R, Bednasz C, Smith N, Morse G, Talal A. Insights into the Exposure Response Relationship for Ribavirin in the Treatment of Chronic Hepatitis C Virus (HCV) infections. Open Forum Infect Dis 2016. [DOI: 10.1093/ofid/ofw172.1495] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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9 |
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20
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Sandler RS, Eisen GM, Talal A, Wurzelmann JI. Rational approach to small polyps found on sigmoidoscopy. J Clin Gastroenterol 1995; 20:317-20. [PMID: 7665822] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/09/2022]
Abstract
Most colorectal cancers are thought to develop from benign adenomas. Because adenomas are found in a large proportion of asymptomatic individuals, most adenomas must remain benign. Current guidelines suggest that colonoscopy is not necessary when hyperplastic polyps are found at screening sigmoidoscopy. Existing data suggest that small adenomatous polyps may also not be associated with substantial risk of current or future malignancy. We suggest that small polyps seen on flexible sigmoidoscopy require neither biopsy nor subsequent colonoscopy. Such an approach requires further study, but could result in substantial cost savings, with modest risk to patients.
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Review |
30 |
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21
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Skopouli FN, Talal A, Galanopoulou V, Tsampoulas CG, Drosos AA, Moutsopoulos HM. Raynaud's phenomenon in primary Sjögren's syndrome. J Rheumatol 1990; 17:618-20. [PMID: 2359071] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Our study describes the prevalence, clinical picture, course and sequelae of Raynaud's phenomenon in patients with primary Sjögren's syndrome. Furthermore, our study compares the clinical, serologic and immunogenetic profile of patients with Raynaud's phenomenon versus those without Raynaud's phenomenon. It seems that Raynaud's phenomenon is a common manifestation (33%) in patients with primary Sjögren's syndrome, precedes sicca manifestations in 42% of patients and follows a pleomorphic course; in some patients (14%) it disappears during the course of Sjögren's syndrome, in others (30%) the frequency of attacks decreases while in a 3rd group (56%) it remains the same. The local clinical sequelae of Raynaud's phenomenon in patients with primary Sjögren's syndrome are swollen hands and evidence of small, soft tissue calcifications on radiographs. Digital pulp ulcers, sclerodactyly or periungal telengiectases are not seen. It seems however, that patients with primary Sjögren's syndrome and Raynaud's phenomenon develop glomerulonephritis, myositis and peripheral neuropathy more often than patients without Raynaud's phenomenon. These differences however, had no statistical significance. Finally, the autoantibody profile is similar in patients with and without Raynaud's phenomenon, while patients without Raynaud's phenomenon and primary Sjögren's syndrome showed a negative but not statistically significant association with the HLA-DR4 alloantigen.
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35 |
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22
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Golia P, Talal A. Editorial comment: diagnosis of acute HIV infection in hepatitis C treatment nonresponders--is extra vigilance required? THE AIDS READER 2003; 13:288-90. [PMID: 12846174] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 03/03/2023]
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Editorial |
22 |
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23
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Sabbagh C, Beyer-Berjot L, Ouaissi M, Zerbib P, Bridoux V, Manceau G, Karoui M, Panis Y, Buscail E, Venara A, Khaoudy I, Gaillard M, Ortega-Deballon P, Viennet M, Thobie A, Menahem B, Eveno C, Bonnel C, Mabrut JY, Badic B, Godet C, Eid Y, Duchalais E, Lakkis Z, Cotte E, Laforest A, Defourneaux V, Maggiorri L, Rebibo L, Christou N, Talal A, Mege D, Bonnamy C, Germain A, Mauvais F, Tresallet C, Ahmed O, Regimbeau JM, Roudie J, Laurent A, Trilling B, Bertrand M, Massalou D, Romain B, Tranchart H, Giger U, Dejardin O, Pellegrin A, Alves A. Risk factors for severe morbidity and definitive stoma after elective surgery for sigmoid diverticulitis: a multicenter national cohort study. Tech Coloproctol 2024; 28:34. [PMID: 38369674 DOI: 10.1007/s10151-023-02906-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/16/2023] [Accepted: 12/18/2023] [Indexed: 02/20/2024]
Abstract
BACKGROUND In the decision to perform elective surgery, it is of great interest to have data about the outcomes of surgery to individualize patients who could safely undergo sigmoid resection. The aim of this study was to provide information on the outcomes of elective sigmoid resection for sigmoid diverticular disease (SDD) at a national level. METHODS All consecutive patients who had elective surgery for SDD (2010-2021) were included in this retrospective, multicenter, cohort study. Patients were identified from institutional review board-approved databases in French member centers of the French Surgical Association. The endpoints of the study were the early and the long-term postoperative outcomes and an evaluation of the risk factors for 90-day severe postoperative morbidity and a definitive stoma after an elective sigmoidectomy for SDD. RESULTS In total, 4617 patients were included. The median [IQR] age was 61 [18.0;100] years, the mean ± SD body mass index (BMI) was 26.8 ± 4 kg/m2, and 2310 (50%) were men. The indications for surgery were complicated diverticulitis in 50% and smoldering diverticulitis in 47.4%. The procedures were performed laparoscopically for 88% and with an anastomosis for 83.8%. The severe complication rate on postoperative day 90 was 11.7%, with a risk of anastomotic leakage of 4.7%. The independent risk factors in multivariate analysis were an American Society of Anesthesiologists (ASA) score ≥ 3, an open approach, and perioperative blood transfusion. Age, perioperative blood transfusion, and Hartmann's procedure were the three independent risk factors for a permanent stoma. CONCLUSIONS This series provides a real-life picture of elective sigmoidectomy for SDD at a national level. TRIAL REGISTRATION Comité National Information et Liberté (CNIL) (n°920361).
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Multicenter Study |
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24
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Karam E, Sabbagh C, Beyer-Bergeot L, Zerbib P, Bridoux V, Manceau G, Panis Y, Buscail E, Venara A, Khaoudy I, Gaillard M, Viennet M, Thobie A, Menahem B, Eveno C, Bonnel C, Mabrut JY, Badic B, Godet C, Eid Y, Duchalais E, Lakkis Z, Cotte E, Laforest A, Desfourneaux V, Maggiori L, Rebibo L, Christou N, Talal A, Aubert M, Bonnamy C, Germain A, Mauvais F, Tresallet C, Roudie J, Laurent A, Trilling B, Bertrand M, Massalou D, Romain B, Tranchart H, Giger-Pabst U, Alves A, Ouaissi M. Comparison of surgical management and outcomes of acute right colic and sigmoid diverticulitis: a French national retrospective cohort study. Tech Coloproctol 2024; 28:149. [PMID: 39508963 DOI: 10.1007/s10151-024-03024-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/20/2024] [Accepted: 09/21/2024] [Indexed: 11/15/2024]
Abstract
BACKGROUND Acute right colic diverticulitis (ARD) is less frequent in Western countries than acute sigmoid diverticulitis (ASD). We aimed to compare the management of ARD and ASD operated on in emergency. METHODS All consecutive patients who had emergency surgery for ASD and ARD (2010-2021) were included in a retrospective, multicenter, cohort study. Patients were identified from databases in French centers that were members of the French Surgical Association. Emergency surgery was performed during the same hospitalization for peritonitis or after failure of conservative treatment. Early and late postoperative outcomes were studied. RESULTS A total of 2297 patients were included with 2256 (98.2%) ASD and 41 (1.8%) ARD patients. Baseline characteristics were similar. Overall, patients were rated Hinchey 3-4 (63.9%, n = 1468, p = 0.287). ARD was more often treated with resection and anastomosis, protected or not (53.7%, n = 22), whereas ASD was mainly treated with resection and terminal ostomy (62.5% (n = 1409), p < 0.001). Median operative time was shorter for ARD (120 vs 146 min, p = 0.04). The group of ARD patients showed a higher prevalence of Clavien III/IV complications compared to the group of ASD patients, although no statistically significant difference was observed (41.5%, n = 17 vs. 27.6%, n = 620, p = 0.054). However 90-day mortality only happened in ASD patients (9.8%, n = 223 vs 0, p = 0.03). ARD patients had more diverticulitis recurrence (46.3%, n = 19 vs 13.4%, n = 303, p < 0.001). Multivariate analysis identified female sex as a protective factor for recurrence [odds ratio (OR) 0.55, p < 0.001] and ARD as a risk factor (OR 8.85, p < 0.001). CONCLUSION Operated on in emergency, ARDs have more resection anastomosis, with a similar rate of complications, less mortality, and more recurrence of diverticulitis than ASD.
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Comparative Study |
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