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1.
Eur Phys J C Part Fields ; 78(3): 256, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-31258409

RESUMO

We use MasterCode to perform a frequentist analysis of the constraints on a phenomenological MSSM model with 11 parameters, the pMSSM11, including constraints from ∼ 36 /fb of LHC data at 13 TeV and PICO, XENON1T and PandaX-II searches for dark matter scattering, as well as previous accelerator and astrophysical measurements, presenting fits both with and without the ( g - 2 ) µ constraint. The pMSSM11 is specified by the following parameters: 3 gaugino masses M 1 , 2 , 3 , a common mass for the first-and second-generation squarks m q ~ and a distinct third-generation squark mass m q ~ 3 , a common mass for the first-and second-generation sleptons m ℓ ~ and a distinct third-generation slepton mass m τ ~ , a common trilinear mixing parameter A, the Higgs mixing parameter µ , the pseudoscalar Higgs mass M A and tan ß . In the fit including ( g - 2 ) µ , a Bino-like χ ~ 1 0 is preferred, whereas a Higgsino-like χ ~ 1 0 is mildly favoured when the ( g - 2 ) µ constraint is dropped. We identify the mechanisms that operate in different regions of the pMSSM11 parameter space to bring the relic density of the lightest neutralino, χ ~ 1 0 , into the range indicated by cosmological data. In the fit including ( g - 2 ) µ , coannihilations with χ ~ 2 0 and the Wino-like χ ~ 1 ± or with nearly-degenerate first- and second-generation sleptons are active, whereas coannihilations with the χ ~ 2 0 and the Higgsino-like χ ~ 1 ± or with first- and second-generation squarks may be important when the ( g - 2 ) µ constraint is dropped. In the two cases, we present χ 2 functions in two-dimensional mass planes as well as their one-dimensional profile projections and best-fit spectra. Prospects remain for discovering strongly-interacting sparticles at the LHC, in both the scenarios with and without the ( g - 2 ) µ constraint, as well as for discovering electroweakly-interacting sparticles at a future linear e + e - collider such as the ILC or CLIC.

2.
Eur Phys J C Part Fields ; 77(4): 268, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28515671

RESUMO

We perform a likelihood analysis of the minimal anomaly-mediated supersymmetry-breaking (mAMSB) model using constraints from cosmology and accelerator experiments. We find that either a wino-like or a Higgsino-like neutralino LSP, [Formula: see text], may provide the cold dark matter (DM), both with similar likelihoods. The upper limit on the DM density from Planck and other experiments enforces [Formula: see text] after the inclusion of Sommerfeld enhancement in its annihilations. If most of the cold DM density is provided by the [Formula: see text], the measured value of the Higgs mass favours a limited range of [Formula: see text] (and also for [Formula: see text] if [Formula: see text]) but the scalar mass [Formula: see text] is poorly constrained. In the wino-LSP case, [Formula: see text] is constrained to about [Formula: see text] and [Formula: see text] to [Formula: see text], whereas in the Higgsino-LSP case [Formula: see text] has just a lower limit [Formula: see text] ([Formula: see text]) and [Formula: see text] is constrained to [Formula: see text] in the [Formula: see text] ([Formula: see text]) scenario. In neither case can the anomalous magnetic moment of the muon, [Formula: see text], be improved significantly relative to its Standard Model (SM) value, nor do flavour measurements constrain the model significantly, and there are poor prospects for discovering supersymmetric particles at the LHC, though there are some prospects for direct DM detection. On the other hand, if the [Formula: see text] contributes only a fraction of the cold DM density, future LHC [Formula: see text]-based searches for gluinos, squarks and heavier chargino and neutralino states as well as disappearing track searches in the wino-like LSP region will be relevant, and interference effects enable [Formula: see text] to agree with the data better than in the SM in the case of wino-like DM with [Formula: see text].

3.
Eur Phys J C Part Fields ; 77(2): 104, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28260982

RESUMO

We perform a likelihood analysis of the constraints from accelerator experiments and astrophysical observations on supersymmetric (SUSY) models with SU(5) boundary conditions on soft SUSY-breaking parameters at the GUT scale. The parameter space of the models studied has seven parameters: a universal gaugino mass [Formula: see text], distinct masses for the scalar partners of matter fermions in five- and ten-dimensional representations of SU(5), [Formula: see text] and [Formula: see text], and for the [Formula: see text] and [Formula: see text] Higgs representations [Formula: see text] and [Formula: see text], a universal trilinear soft SUSY-breaking parameter [Formula: see text], and the ratio of Higgs vevs [Formula: see text]. In addition to previous constraints from direct sparticle searches, low-energy and flavour observables, we incorporate constraints based on preliminary results from 13 TeV LHC searches for jets + [Formula: see text] events and long-lived particles, as well as the latest PandaX-II and LUX searches for direct Dark Matter detection. In addition to previously identified mechanisms for bringing the supersymmetric relic density into the range allowed by cosmology, we identify a novel [Formula: see text] coannihilation mechanism that appears in the supersymmetric SU(5) GUT model and discuss the role of [Formula: see text] coannihilation. We find complementarity between the prospects for direct Dark Matter detection and SUSY searches at the LHC.

4.
Eur Phys J C Part Fields ; 75(10): 500, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26543400

RESUMO

Different mechanisms operate in various regions of the MSSM parameter space to bring the relic density of the lightest neutralino, [Formula: see text], assumed here to be the lightest SUSY particle (LSP) and thus the dark matter (DM) particle, into the range allowed by astrophysics and cosmology. These mechanisms include coannihilation with some nearly degenerate next-to-lightest supersymmetric particle such as the lighter stau [Formula: see text], stop [Formula: see text] or chargino [Formula: see text], resonant annihilation via direct-channel heavy Higgs bosons H / A, the light Higgs boson h or the Z boson, and enhanced annihilation via a larger Higgsino component of the LSP in the focus-point region. These mechanisms typically select lower-dimensional subspaces in MSSM scenarios such as the CMSSM, NUHM1, NUHM2, and pMSSM10. We analyze how future LHC and direct DM searches can complement each other in the exploration of the different DM mechanisms within these scenarios. We find that the [Formula: see text] coannihilation regions of the CMSSM, NUHM1, NUHM2 can largely be explored at the LHC via searches for [Formula: see text] events and long-lived charged particles, whereas their H / A funnel, focus-point and [Formula: see text] coannihilation regions can largely be explored by the LZ and Darwin DM direct detection experiments. We find that the dominant DM mechanism in our pMSSM10 analysis is [Formula: see text] coannihilation: parts of its parameter space can be explored by the LHC, and a larger portion by future direct DM searches.

5.
Eur Phys J C Part Fields ; 75(9): 422, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26543402

RESUMO

We present a frequentist analysis of the parameter space of the pMSSM10, in which the following ten soft SUSY-breaking parameters are specified independently at the mean scalar top mass scale [Formula: see text]: the gaugino masses [Formula: see text], the first-and second-generation squark masses [Formula: see text], the third-generation squark mass [Formula: see text], a common slepton mass [Formula: see text] and a common trilinear mixing parameter A, as well as the Higgs mixing parameter [Formula: see text], the pseudoscalar Higgs mass [Formula: see text] and [Formula: see text], the ratio of the two Higgs vacuum expectation values. We use the MultiNest sampling algorithm with [Formula: see text]1.2 [Formula: see text] points to sample the pMSSM10 parameter space. A dedicated study shows that the sensitivities to strongly interacting sparticle masses of ATLAS and CMS searches for jets, leptons [Formula: see text][Formula: see text] signals depend only weakly on many of the other pMSSM10 parameters. With the aid of the Atom and Scorpion codes, we also implement the LHC searches for electroweakly interacting sparticles and light stops, so as to confront the pMSSM10 parameter space with all relevant SUSY searches. In addition, our analysis includes Higgs mass and rate measurements using the HiggsSignals code, SUSY Higgs exclusion bounds, the measurements of [Formula: see text] by LHCb and CMS, other B-physics observables, electroweak precision observables, the cold dark matter density and the XENON100 and LUX searches for spin-independent dark matter scattering, assuming that the cold dark matter is mainly provided by the lightest neutralino [Formula: see text]. We show that the pMSSM10 is able to provide a supersymmetric interpretation of [Formula: see text], unlike the CMSSM, NUHM1 and NUHM2. As a result, we find (omitting Higgs rates) that the minimum [Formula: see text] with 18 degrees of freedom (d.o.f.) in the pMSSM10, corresponding to a [Formula: see text] probability of 30.8 %, to be compared with [Formula: see text] in the CMSSM (NUHM1) (NUHM2). We display the one-dimensional likelihood functions for sparticle masses, and we show that they may be significantly lighter in the pMSSM10 than in the other models, e.g., the gluino may be as light as [Formula: see text]1250 [Formula: see text] at the 68 % CL, and squarks, stops, electroweak gauginos and sleptons may be much lighter than in the CMSSM, NUHM1 and NUHM2. We discuss the discovery potential of future LHC runs, [Formula: see text] colliders and direct detection experiments.

6.
Eur Phys J C Part Fields ; 74(12): 3212, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25983642

RESUMO

We make a frequentist analysis of the parameter space of the NUHM2, in which the soft supersymmetry (SUSY)-breaking contributions to the masses of the two Higgs multiplets, [Formula: see text], vary independently from the universal soft SUSY-breaking contributions [Formula: see text] to the masses of squarks and sleptons. Our analysis uses the MultiNest sampling algorithm with over [Formula: see text] points to sample the NUHM2 parameter space. It includes the ATLAS and CMS Higgs mass measurements as well as the ATLAS search for supersymmetric jets + [Formula: see text] signals using the full LHC Run 1 data, the measurements of [Formula: see text] by LHCb and CMS together with other B-physics observables, electroweak precision observables and the XENON100 and LUX searches for spin-independent dark-matter scattering. We find that the preferred regions of the NUHM2 parameter space have negative SUSY-breaking scalar masses squared at the GUT scale for squarks and sleptons, [Formula: see text], as well as [Formula: see text]. The tension present in the CMSSM and NUHM1 between the supersymmetric interpretation of [Formula: see text] and the absence to date of SUSY at the LHC is not significantly alleviated in the NUHM2. We find that the minimum [Formula: see text] with 21 degrees of freedom (dof) in the NUHM2, to be compared with [Formula: see text] in the CMSSM, and [Formula: see text] in the NUHM1. We find that the one-dimensional likelihood functions for sparticle masses and other observables are similar to those found previously in the CMSSM and NUHM1.

7.
Eur Phys J C Part Fields ; 74(3): 2809, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25814884

RESUMO

We discuss the allowed parameter spaces of supersymmetric scenarios in light of improved Higgs mass predictions provided by FeynHiggs 2.10.0. The Higgs mass predictions combine Feynman-diagrammatic results with a resummation of leading and subleading logarithmic corrections from the stop/top sector, which yield a significant improvement in the region of large stop masses. Scans in the pMSSM parameter space show that, for given values of the soft supersymmetry-breaking parameters, the new logarithmic contributions beyond the two-loop order implemented in FeynHiggs tend to give larger values of the light CP-even Higgs mass, [Formula: see text], in the region of large stop masses than previous predictions that were based on a fixed-order Feynman-diagrammatic result, though the differences are generally consistent with the previous estimates of theoretical uncertainties. We re-analyse the parameter spaces of the CMSSM, NUHM1 and NUHM2, taking into account also the constraints from CMS and LHCb measurements of [Formula: see text]and ATLAS searches for [Formula: see text] events using 20/fb of LHC data at 8 TeV. Within the CMSSM, the Higgs mass constraint disfavours [Formula: see text], though not in the NUHM1 or NUHM2.

8.
Eur Phys J C Part Fields ; 74(6): 2922, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25814897

RESUMO

We analyze the impact of data from the full Run 1 of the LHC at 7 and 8 TeV on the CMSSM with [Formula: see text] and [Formula: see text] and the NUHM1 with [Formula: see text], incorporating the constraints imposed by other experiments such as precision electroweak measurements, flavour measurements, the cosmological density of cold dark matter and the direct search for the scattering of dark matter particles in the LUX experiment. We use the following results from the LHC experiments: ATLAS searches for events with [Formula: see text] accompanied by jets with the full 7 and 8 TeV data, the ATLAS and CMS measurements of the mass of the Higgs boson, the CMS searches for heavy neutral Higgs bosons and a combination of the LHCb and CMS measurements of [Formula: see text] and [Formula: see text]. Our results are based on samplings of the parameter spaces of the CMSSM for both [Formula: see text] and [Formula: see text] and of the NUHM1 for [Formula: see text] with 6.8[Formula: see text], 6.2[Formula: see text] and 1.6[Formula: see text] points, respectively, obtained using the MultiNest tool. The impact of the Higgs-mass constraint is assessed using FeynHiggs 2.10.0, which provides an improved prediction for the masses of the MSSM Higgs bosons in the region of heavy squark masses. It yields in general larger values of [Formula: see text] than previous versions of FeynHiggs, reducing the pressure on the CMSSM and NUHM1. We find that the global [Formula: see text] functions for the supersymmetric models vary slowly over most of the parameter spaces allowed by the Higgs-mass and the [Formula: see text] searches, with best-fit values that are comparable to the [Formula: see text] for the best Standard Model fit. We provide 95 % CL lower limits on the masses of various sparticles and assess the prospects for observing them during Run 2 of the LHC.

10.
Mil Med ; 166(7): 571-6, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11469026

RESUMO

Systems for the staging of individuals with human immunodeficiency virus type 1 (HIV-1) infection were developed 15 years ago. Subsequently, assays for quantitating HIV-1 RNA and immunophenotyping of lymphocyte subsets have been developed and validated. The utility of these assays for improved staging in early disease was evaluated in 256 HIV-infected adults (52% minority) with CD4 counts > or = 400 cells/microL followed in U.S. military medical centers before the highly active anti-retroviral therapy era. HIV viral load (RNA) was quantitated; the frequencies of select CD4+ immunophenotypes were determined in 112 subjects. The results were analyzed in relation to three outcome measures: death, first acquired immunodeficiency syndrome-defining opportunistic infection, and CD4 count < or = 200 cells/microL. Serum RNA level and CD4 count were each found to be predictive of all three outcomes. In addition, increases in the T-cell subsets CD28-CD4+ and CD29+CD26-CD4+ were found to be independently predictive of more rapid progression. The classification of early-stage HIV patients is improved by the quantitation of both viral RNA and T-lymphocyte subsets.


Assuntos
Infecções por HIV/imunologia , HIV-1 , RNA Viral/sangue , Subpopulações de Linfócitos T , Adulto , Distribuição de Qui-Quadrado , Progressão da Doença , Feminino , Humanos , Contagem de Linfócitos , Masculino , Avaliação de Resultados em Cuidados de Saúde , Prognóstico , Modelos de Riscos Proporcionais , Estatísticas não Paramétricas , Análise de Sobrevida
11.
Clin Infect Dis ; 32(11): 1639-42, 2001 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-11340538

RESUMO

We report 32 cases of culture-proven influenza A (A/Sydney) caused by virus imported into mainland US military barracks from Puerto Rico in July 1999. Despite the fact that the shelf life of the influenza vaccine is 18 months and that the outbreak strain was a component of the previous year's vaccine, no vaccine was available from manufacturers, owing to US Food and Drug Administration regulations. Formal consideration should be given to extending the date of expiration and to maintaining a supply of the influenza vaccine year-round.


Assuntos
Surtos de Doenças , Vírus da Influenza A , Influenza Humana/epidemiologia , Humanos , Vacinas contra Influenza , Influenza Humana/fisiopatologia , Influenza Humana/prevenção & controle , Estados Unidos/epidemiologia
12.
J Infect Dis ; 183(11): 1574-85, 2001 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-11335892

RESUMO

If CC chemokine receptor 5 (CCR5)-dependent mechanisms at the time of initial virus exposure are important determinants of virus entry and disease outcome, then the polymorphisms in CCR5 that influence risk of transmission and disease progression should be similar; this hypothesis was tested in a cohort of 649 Argentinean children exposed perinatally to human immunodeficiency virus type 1 (HIV-1). Two lines of evidence support this hypothesis. First, CCR5 haplotype pairs associated with enhanced risk of transmission were the chief predictors of a faster disease course. Second, some of the haplotype pairs associated with altered rates of transmission and disease progression in children were similar to those that we previously found influenced outcome in European American adults. This concordance suggests that CCR5 haplotypes may serve as genetic rheostats that influence events occurring shortly after initial virus exposure, dictating not only virus entry but, by extension, also the extent of early viral replication.


Assuntos
Infecções por HIV/transmissão , HIV-1 , Transmissão Vertical de Doenças Infecciosas , Receptores CCR5/genética , Síndrome da Imunodeficiência Adquirida/transmissão , Argentina , Estudos de Coortes , Progressão da Doença , Feminino , Variação Genética , Genótipo , Infecções por HIV/genética , Infecções por HIV/virologia , Haplótipos , Humanos , Lactente , Gravidez , Complicações Infecciosas na Gravidez/virologia
13.
Proc Natl Acad Sci U S A ; 98(9): 5199-204, 2001 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-11320252

RESUMO

Expression of CC chemokine receptor 5 (CCR5), the major coreceptor for HIV-1 cell entry, and its ligands (e.g., RANTES and MIP-1alpha) is widely regarded as central to the pathogenesis of HIV-1 infection. By surveying nearly 3,000 HIV+ and HIV- individuals from worldwide populations for polymorphisms in the genes encoding RANTES, MIP-1alpha, and CCR5, we show that the evolutionary histories of human populations have had a significant impact on the distribution of variation in these genes, and that this may be responsible, in part, for the heterogeneous nature of the epidemiology of the HIV-1 pandemic. The varied distribution of RANTES haplotypes (AC, GC, and AG) associated with population-specific HIV-1 transmission- and disease-modifying effects is a striking example. Homozygosity for the AC haplotype was associated with an increased risk of acquiring HIV-1 as well as accelerated disease progression in European Americans, but not in African Americans. Yet, the prevalence of the ancestral AC haplotype is high in individuals of African origin, but substantially lower in non-Africans. In a Japanese cohort, AG-containing RANTES haplotype pairs were associated with a delay in disease progression; however, we now show that their contribution to HIV-1 pathogenesis and epidemiology in other parts of the world is negligible because the AG haplotype is infrequent in non-Far East Asians. Thus, the varied distribution of RANTES, MIP-1alpha, and CCR5 haplotype pairs and their population-specific phenotypic effects on HIV-1 susceptibility and disease progression results in a complex pattern of biological determinants of HIV-1 epidemiology. These findings have important implications for the design, assessment, and implementation of effective HIV-1 intervention and prevention strategies.


Assuntos
Quimiocina CCL5/genética , Predisposição Genética para Doença/genética , Variação Genética/genética , Infecções por HIV/epidemiologia , Infecções por HIV/genética , Proteínas Inflamatórias de Macrófagos/genética , Receptores CCR5/genética , África/epidemiologia , África/etnologia , Povo Asiático/genética , População Negra/genética , Quimiocina CCL3 , Quimiocina CCL4 , Estudos de Coortes , Etnicidade/genética , Europa (Continente)/epidemiologia , Europa (Continente)/etnologia , Frequência do Gene , Infecções por HIV/transmissão , Infecções por HIV/virologia , HIV-1/fisiologia , Haplótipos/genética , Humanos , Polimorfismo de Nucleotídeo Único/genética , Estados Unidos/epidemiologia , População Branca/genética
14.
J Infect Dis ; 183(7): 1000-8, 2001 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-11237823

RESUMO

Influenza virus stimulation of leukocytes induces factors that suppress human immunodeficiency virus (HIV). The effect of influenza vaccination on influenza-induced anti-HIV activity was investigated. Influenza vaccine was administered to 25 control subjects and 20 HIV-infected patients. Antiviral activity, cytokine production, and influenza antibodies were assessed before and 2 and 6 weeks after vaccination. Immunization induced a statistically significant increase in antiviral activity in control subjects but not in HIV patients, although the number of patients who generated this activity increased. Pre- and postvaccination levels of anti-HIV activity were significantly lower in HIV patients. Vaccination of control subjects and HIV patients induced increases in production of interleukin-2 and interferon (IFN)-gamma, but not of IFN-alpha. Virus load and CD4 cell counts were not significantly altered. This study demonstrates impairment of antiviral activity in HIV patients, in addition to deficiencies in antibody responses and cytokine production. In summary, influenza vaccination can induce an increase in multiple immunologic components that remained impaired in HIV patients.


Assuntos
Infecções por HIV/virologia , HIV-1/imunologia , Vacinas contra Influenza/administração & dosagem , Anticorpos Antivirais/sangue , Relação CD4-CD8 , Infecções por HIV/sangue , Infecções por HIV/imunologia , Soronegatividade para HIV , HIV-1/isolamento & purificação , Humanos , Interferon gama/análise , Interferon gama/imunologia , Interleucina-2/análise , Interleucina-2/imunologia , Leucócitos Mononucleares/imunologia , Orthomyxoviridae/imunologia , Fatores de Tempo , Vacinação , Vacinas de Produtos Inativados/administração & dosagem , Carga Viral , Replicação Viral
15.
Hum Immunol ; 62(2): 143-5, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11182224

RESUMO

One of the proposed mechanisms for resistance to human immunodeficiency virus-1 (HIV-1) infection is the presence of antibodies against receptor for CC-chemokines (CCR5). These antibodies, detected in sera of uninfected individuals exposed to HIV, have been shown to downmodulate surface CCR5 in vivo and are able to neutralize the infectivity of CCR5 strains in vitro. To address the potential role of anti-CCR5 antibodies in HIV infection, we analyzed anti-CCR5 antibody levels in plasma from HIV-infected patients who present a wide range of CD4(+) T-cell counts and viral load. Increased levels of anti-CCR5 antibodies were found in plasma from 13/46 HIV-positive donors compared with healthy controls (0/36). However, antibody levels were not associated with disease stage evaluated by CD4(+) T-cell counts and viral load.


Assuntos
Soropositividade para HIV/imunologia , Imunoglobulina G/sangue , Receptores CCR5/imunologia , Sequência de Aminoácidos , Biomarcadores/sangue , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD4-Positivos/patologia , Estudos Transversais , Ensaio de Imunoadsorção Enzimática , Soropositividade para HIV/sangue , Soropositividade para HIV/virologia , Humanos , Contagem de Linfócitos , Dados de Sequência Molecular , Prognóstico , Carga Viral
16.
J Infect Dis ; 183(5): 831-4, 2001 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-11181164

RESUMO

Coronary artery disease is an inflammatory condition associated with several infections. We prospectively evaluated 155 consecutive patients undergoing coronary angiography for evidence of Bartonella species and Coxiella burnetii infection. All Bartonella cultures were found to be negative. Multivariable logistic regression analysis that controlled for potential confounding factors revealed no association between coronary artery disease and seropositivity to Bartonella henselae (odds ratio [OR], 0.852; 95% confidence interval [CI], 0.293-2.476), Bartonella quintana (OR, 0.425; 95% CI, 0.127-1.479), C. burnetii phase 1 (OR, undefined), and C. burnetii phase 2 (OR, 0.731; 95% CI, 0.199-2.680). The geometric mean titer (GMT) for C. burnetii phase 1 assay was slightly higher in persons with coronary artery disease than in those without such disease (P<.02). B. henselae, B. quintana, and C. burnetii seropositivity was not strongly associated with coronary artery disease. On the basis of GMTs, C. burnetii infection may have a modest association with coronary artery disease.


Assuntos
Infecções por Bartonella/complicações , Bartonella/isolamento & purificação , Doença das Coronárias/etiologia , Coxiella burnetii/isolamento & purificação , Febre Q/complicações , Infecções por Bartonella/epidemiologia , Estudos de Casos e Controles , Angiografia Coronária , Doença das Coronárias/microbiologia , Estudos Transversais , Feminino , Humanos , Modelos Logísticos , Masculino , Razão de Chances , Ohio/epidemiologia , Estudos Prospectivos , Febre Q/epidemiologia , Fatores de Risco , Estudos Soroepidemiológicos
17.
Eur J Immunol ; 30(7): 2048-55, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10940894

RESUMO

The present study investigates the role of the HIV-suppressive beta-chemokines macrophage inflammatory protein (MIP)-1alpha, MIP-1 and RANTES in activation-induced cell death (AICD). A pool of these beta-chemokines reduced anti-CD3-induced apoptosis of T cell blasts from healthy blood donors in a dose-dependent manner. Although the pooled beta-chemokines were more effective, the inhibitory effect could also be mediated by each of the individual chemokines and was blocked by neutralizing anti-chemokine antibodies. The beta-chemokines also inhibited pokeweed mitogen/staphylococcal enterotoxin B-induced T lymphocyte apoptosis in 33/49 HIV-infected (HIV+) individuals. This anti-apoptotic effect was not correlated with the patients' CD4 T cell counts. beta-chemokines did not lead to altered secretion of IL-2, IL-4, IFN-gamma or IL-10 in response to activation stimuli in either normal T cell blasts or peripheral blood mononuclear cells from HIV+ individuals. Co-incubation with beta-chemokines did not inhibit anti-CD3-induced expression of cell surface Fas ligand, nor did it alter levels of the death receptor Fas or Bcl-2 in T cell blasts, suggesting that the beta-chemokines are blocking AICD downstream of Fas. These observations indicate that beta-chemokines may play a novel role as modulators of AICD, in addition to their known role as chemoattractants and inhibitors of HIV replication.


Assuntos
Apoptose/imunologia , Quimiocina CCL5/imunologia , Infecções por HIV/imunologia , Ativação Linfocitária/imunologia , Proteínas Inflamatórias de Macrófagos/imunologia , Linfócitos T/imunologia , Antígenos CD/biossíntese , Antígenos de Diferenciação de Linfócitos T/biossíntese , Apoptose/efeitos dos fármacos , Complexo CD3/imunologia , Células Cultivadas , Quimiocina CCL3 , Quimiocina CCL4 , Quimiocina CCL5/biossíntese , Quimiocina CCL5/farmacologia , Quimiocinas CC/farmacologia , Enterotoxinas/farmacologia , Proteína Ligante Fas , Infecções por HIV/sangue , Humanos , Interferon gama/biossíntese , Interleucina-10/biossíntese , Interleucina-2/biossíntese , Interleucina-4/biossíntese , Lectinas Tipo C , Ativação Linfocitária/efeitos dos fármacos , Proteínas Inflamatórias de Macrófagos/biossíntese , Proteínas Inflamatórias de Macrófagos/farmacologia , Glicoproteínas de Membrana/biossíntese , Mitógenos de Phytolacca americana/farmacologia , Proteínas Proto-Oncogênicas c-bcl-2/biossíntese , Staphylococcus aureus , Linfócitos T/citologia , Linfócitos T/efeitos dos fármacos , Receptor fas/biossíntese
18.
J Virol ; 74(10): 4505-11, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10775586

RESUMO

It is now recognized that, in addition to drug-mediated therapies against human immunodeficiency virus type 1 (HIV-1), the immune system can exert antiviral effects via CD8(+) T-cell-generated anti-HIV factors. This study demonstrates that (i) supernatants from peripheral blood mononuclear cells (PBMC) stimulated with influenza A virus inhibit replication of CCR5- and CXCR4-tropic HIV-1 isolates prior to reverse transcription; (ii) the HIV-suppressive supernatants can be generated by CD4- or CD8-depleted PBMC; (iii) this anti-HIV activity is partially due to alpha interferon (IFN-alpha), but not to IFN-gamma, IFN-beta, the beta-chemokines MIP-1alpha, MIP-1beta, and RANTES, or interleukin-16; (iv) the anti-HIV activity is generated equally well by PBMC cultured with either infectious or UV-inactivated influenza A virus; and (v) the antiviral activity can be generated by influenza A-stimulated PBMC from HIV-infected individuals. These findings represent a novel mechanism for inhibition of HIV-1 replication that differs from the previously described CD8 anti-HIV factors (MIP-1alpha, MIP-1beta, RANTES, and CD8 antiviral factor).


Assuntos
Antivirais/fisiologia , HIV-1/fisiologia , Vírus da Influenza A/imunologia , Leucócitos Mononucleares/imunologia , Replicação Viral , Anticorpos/imunologia , Células Cultivadas , Citocinas/imunologia , Citocinas/metabolismo , Citometria de Fluxo , HIV-1/imunologia , Humanos , Vacinas contra Influenza/imunologia , Interferon-alfa/imunologia , Interferon-alfa/metabolismo , Leucócitos Mononucleares/metabolismo , Ativação Linfocitária , Subpopulações de Linfócitos T/imunologia , Transcrição Gênica
20.
J Biol Chem ; 275(25): 18946-61, 2000 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-10747879

RESUMO

Polymorphisms in CC chemokine receptor 5 (CCR5), the major coreceptor of human immunodeficiency virus 1 (HIV-1) and simian immunodeficiency virus (SIV), have a major influence on HIV-1 transmission and disease progression. The effects of these polymorphisms may, in part, account for the differential pathogenesis of HIV-1 (immunosuppression) and SIV (natural resistance) in humans and non-human primates, respectively. Thus, understanding the genetic basis underlying species-specific responses to HIV-1 and SIV could reveal new anti-HIV-1 therapeutic strategies for humans. To this end, we compared CCR5 structure/evolution and regulation among humans, apes, Old World Monkeys, and New World Monkeys. The evolution of the CCR5 cis-regulatory region versus the open reading frame as well as among different domains of the open reading frame differed from one another. CCR5 cis-regulatory region sequence variation in humans was substantially higher than anticipated. Based on this variation, CCR5 haplotypes could be organized into seven evolutionarily distinct human haplogroups (HH) that we designated HHA, -B, -C, -D, -E, -F, and -G. HHA haplotypes were defined as ancestral to all other haplotypes by comparison to the CCR5 haplotypes of non-human primates. Different human and non-human primate CCR5 haplotypes were associated with differential transcriptional regulation, and various polymorphisms resulted in modified DNA-nuclear protein interactions, including altered binding of members of the NF-kappaB family of transcription factors. We identified novel CCR5 untranslated mRNA sequences that were conserved in human and non-human primates. In some primates, mutations at exon-intron boundaries caused loss of expression of selected CCR5 mRNA isoforms or production of novel mRNA isoforms. Collectively, these findings suggest that the response to HIV-1 and SIV infection in primates may have been driven, in part, by evolution of the elements controlling CCR5 transcription and translation.


Assuntos
Evolução Molecular , HIV-1/genética , RNA Mensageiro/genética , Receptores CCR5/genética , Vírus da Imunodeficiência Símia/genética , Fatores de Transcrição/metabolismo , Transcrição Gênica , Animais , Sequência de Bases , HIV-1/patogenicidade , Haplótipos , Humanos , Dados de Sequência Molecular , Polimorfismo Genético , Primatas/genética , Ligação Proteica , Splicing de RNA , Sequências Reguladoras de Ácido Nucleico , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Homologia de Sequência do Ácido Nucleico , Vírus da Imunodeficiência Símia/patogenicidade
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