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1.
Infect Immun ; 88(3)2020 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-31871098

RESUMO

Activated B cells modulate infection by differentiating into pathogen-specific antibody-producing effector plasmablasts/plasma cells, memory cells, and immune regulatory B cells. In this context, the B cell phenotypes that infiltrate the central nervous system during human immunodeficiency virus (HIV) and cryptococcal meningitis coinfection are ill defined. We characterized clinical parameters, mortality, and B cell phenotypes in blood and cerebrospinal fluid (CSF) by flow cytometry in HIV-infected adults with cryptococcal (n = 31) and noncryptococcal (n = 12) meningitis and in heathy control subjects with neither infection (n = 10). Activation of circulating B cells (CD21low) was significantly higher in the blood of subjects with HIV infection than in that of healthy controls and greater yet in matched CSF B cells (P < 0.001). Among B cell subsets, elevated frequencies of memory and plasmablasts/plasma cells most clearly distinguished the CSF from blood compartments. With cryptococcal meningitis, lower frequencies of expression of the regulatory protein programmed death-1 (PD-1) on plasmablasts/plasma cells in blood (median, 7%) at presentation were associated with significantly decreased 28-day survival (29% [4/14 subjects]), whereas higher PD-1 expression (median, 46%) characterized subjects with higher survival (88% [14/16 subjects]). With HIV infection, B cell differentiation and regulatory markers are discrete elements of the circulating and CSF compartments with clinical implications for cryptococcal disease outcome, potentially due to their effects on the fungus and other local immune cells.


Assuntos
Linfócitos B/imunologia , Compartimento Celular/imunologia , Líquido Cefalorraquidiano/imunologia , Infecções por HIV/complicações , Meningite Criptocócica/imunologia , Adulto , Estudos de Casos e Controles , Coinfecção , Feminino , Infecções por HIV/imunologia , Humanos , Masculino , Meningite Criptocócica/sangue , Meningite Criptocócica/líquido cefalorraquidiano , Pessoa de Meia-Idade , Carga Viral
2.
Nucleic Acids Res ; 46(5): 2537-2547, 2018 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-29385522

RESUMO

Numerous mammalian proto-oncogene and other growth-regulatory transcripts are upregulated in malignancy due to abnormal mRNA stabilization. In hepatoma cells expressing a hepatitis C virus (HCV) subgenomic replicon, we found that the viral nonstructural protein 5A (NS5A), a protein known to bind to viral RNA, also bound specifically to human cellular transcripts that encode regulators of cell growth and apoptosis, and this binding correlated with transcript stabilization. An important subset of human NS5A-target transcripts contained GU-rich elements, sequences known to destabilize mRNA. We found that NS5A bound to GU-rich elements in vitro and in cells. Mutation of the NS5A zinc finger abrogated its GU-rich element-binding and mRNA stabilizing activities. Overall, we identified a molecular mechanism whereby HCV manipulates host gene expression by stabilizing host transcripts in a manner that would promote growth and prevent death of virus-infected cells, allowing the virus to establish chronic infection and lead to the development of hepatocellular carcinoma.


Assuntos
Estabilidade de RNA , Proteínas não Estruturais Virais/metabolismo , Linhagem Celular Tumoral , Células HeLa , Hepacivirus/metabolismo , Humanos , Proto-Oncogene Mas , RNA Mensageiro/metabolismo , Proteínas não Estruturais Virais/química
3.
BMC Neurol ; 19(1): 10, 2019 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-30646840

RESUMO

BACKGROUND: A few reliable national data concerning the etiology of non-traumatic spinal cord injury (SCI) in sub-Sahara Africa exists, mainly because of the limitations of diagnostic imaging. These are both expensive and mostly unavailable in several resource-limited settings. Only a few studies have employed the magnetic resonance imaging (MRI) in documenting non-traumatic SCI and most of these studies are from South Africa. We sought to describe the clinical presentation, MRI radiological patterns, and one-year survival among subjects with non-traumatic SCI in Uganda. METHODS: We enrolled a prospective cohort of 103 participants with non-traumatic SCI at Mulago National Referral Hospital Kampala, Uganda in 2013-2015. Participants received standard of care management, with surgical intervention as needed, with one-year follow up. Data were analyzed using Descriptive statistics. RESULTS: In 103 participants with non-traumatic SCI, the median (IQR) age was 37 (18, 85) years and 25% of the participants were HIV-infected. Paraplegia/paraparesis was the most common clinical presentation in 70% (n = 72). Severe disease was present in 82% (n = 85) as per American Spinal Injury Association (ASIA) scale A-C. On MRI, 50% had extradural lesions. However, bone lesions accounted for only 75% of all the extradural lesions. More than 60% of the patients had lesions that could only be diagnosed on MRI. Deaths occurred in 42% (n = 44) of participants, with the highest mortality among those with extradural lesions (60%). CONCLUSION: The mortality following non-traumatic spinal cord injuries in Uganda is high. We demonstrated an equal distribution between extradural and intradural lesions, which differs from the historical predominance of extradural lesions. Increased utilization of MRI particularly among young age groups is needed to make a diagnosis.


Assuntos
Imageamento por Ressonância Magnética , Traumatismos da Medula Espinal/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Traumatismos da Medula Espinal/diagnóstico por imagem , Uganda/epidemiologia , Adulto Jovem
4.
J Immunol ; 198(4): 1627-1637, 2017 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-28069805

RESUMO

Many pulmonary infections elicit lymphocyte responses that lead to an accumulation of granulocytes in the lungs. A variety of lymphocytes are capable of directing eosinophils or neutrophils to the lungs, but the contribution of each subset remains enigmatic. In this study, we used a murine model to examine lymphocyte subsets that ultimately drive the eosinophil or neutrophil response to infection with the fungal pathogen Cryptococcus neoformans. We show that granulocytes are produced in the bone marrow, released into the blood stream, and accumulate in the lungs under the instruction of lung parenchymal lymphocytes. The eosinophils that populated the lungs of wild-type animals were highly dependent on Th cells or IL-5. Surprisingly, infected mice with Th cell impairment experienced a compensatory neutrophil response that required IL-17A. This unexpected swing in the response prompted us to investigate the ability of different lymphocyte subsets to produce this dichotomous eosinophilia or neutrophilia. We used mice with lymphocyte deficiencies to determine which of the remaining IL-5- or IL-17A-producing lymphocyte subsets dominated the neutrophil or eosinophil response. Finally, skewing the response toward neutrophil-inducing lymphocytes correlated with accelerated disease. Our data collectively demonstrate that the predominance of a lymphocyte subset determines the functional consequences of an immune response to pulmonary fungal infection that can ultimately affect disease.


Assuntos
Criptococose/imunologia , Eosinófilos/imunologia , Pneumopatias Fúngicas/imunologia , Pulmão/imunologia , Subpopulações de Linfócitos/imunologia , Neutrófilos/imunologia , Animais , Células da Medula Óssea/imunologia , Criptococose/microbiologia , Cryptococcus neoformans/imunologia , Modelos Animais de Doenças , Eosinofilia/etiologia , Eosinofilia/imunologia , Interleucina-17/imunologia , Interleucina-5/imunologia , Pulmão/citologia , Pulmão/microbiologia , Pneumopatias Fúngicas/microbiologia , Camundongos
5.
J Immunol ; 196(1): 365-74, 2016 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-26590316

RESUMO

Lethal disease caused by the fungus Cryptococcus neoformans is a consequence of the combined failure to control pulmonary fungal replication and immunopathology caused by induced type 2 Th2 cell responses in animal models. In order to gain insights into immune regulatory networks, we examined the role of regulatory T (Treg) cells in suppression of Th2 cells using a mouse model of experimental cryptococcosis. Upon pulmonary infection with Cryptococcus, Treg cells accumulated in the lung parenchyma independently of priming in the draining lymph node. Using peptide-MHC class II molecules to identify Cryptococcus-specific Treg cells combined with genetic fate-mapping, we noted that a majority of the Treg cells found in the lungs were induced during the infection. Additionally, we found that Treg cells used the transcription factor, IFN regulatory factor 4, to dampen harmful Th2 cell responses, as well as mediate chemokine retention of Treg cells in the lungs. Taken together, induction and IFN regulatory factor 4-dependent localization of Treg cells in the lungs allow Treg cells to suppress the deleterious effects of Th2 cells during cryptococcal infection.


Assuntos
Criptococose/imunologia , Cryptococcus neoformans/imunologia , Pneumopatias Fúngicas/imunologia , Linfócitos T Reguladores/imunologia , Células Th2/imunologia , Animais , Criptococose/microbiologia , Modelos Animais de Doenças , Fatores Reguladores de Interferon/imunologia , Pulmão/citologia , Pulmão/imunologia , Pulmão/microbiologia , Linfonodos/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Receptores CCR5/imunologia
6.
N Engl J Med ; 370(26): 2487-98, 2014 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-24963568

RESUMO

BACKGROUND: Cryptococcal meningitis accounts for 20 to 25% of acquired immunodeficiency syndrome-related deaths in Africa. Antiretroviral therapy (ART) is essential for survival; however, the question of when ART should be initiated after diagnosis of cryptococcal meningitis remains unanswered. METHODS: We assessed survival at 26 weeks among 177 human immunodeficiency virus-infected adults in Uganda and South Africa who had cryptococcal meningitis and had not previously received ART. We randomly assigned study participants to undergo either earlier ART initiation (1 to 2 weeks after diagnosis) or deferred ART initiation (5 weeks after diagnosis). Participants received amphotericin B (0.7 to 1.0 mg per kilogram of body weight per day) and fluconazole (800 mg per day) for 14 days, followed by consolidation therapy with fluconazole. RESULTS: The 26-week mortality with earlier ART initiation was significantly higher than with deferred ART initiation (45% [40 of 88 patients] vs. 30% [27 of 89 patients]; hazard ratio for death, 1.73; 95% confidence interval [CI], 1.06 to 2.82; P=0.03). The excess deaths associated with earlier ART initiation occurred 2 to 5 weeks after diagnosis (P=0.007 for the comparison between groups); mortality was similar in the two groups thereafter. Among patients with few white cells in their cerebrospinal fluid (<5 per cubic millimeter) at randomization, mortality was particularly elevated with earlier ART as compared with deferred ART (hazard ratio, 3.87; 95% CI, 1.41 to 10.58; P=0.008). The incidence of recognized cryptococcal immune reconstitution inflammatory syndrome did not differ significantly between the earlier-ART group and the deferred-ART group (20% and 13%, respectively; P=0.32). All other clinical, immunologic, virologic, and microbiologic outcomes, as well as adverse events, were similar between the groups. CONCLUSIONS: Deferring ART for 5 weeks after the diagnosis of cryptococcal meningitis was associated with significantly improved survival, as compared with initiating ART at 1 to 2 weeks, especially among patients with a paucity of white cells in cerebrospinal fluid. (Funded by the National Institute of Allergy and Infectious Diseases and others; COAT ClinicalTrials.gov number, NCT01075152.).


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/tratamento farmacológico , Síndrome da Imunodeficiência Adquirida/tratamento farmacológico , Antirretrovirais/administração & dosagem , Meningite Criptocócica/tratamento farmacológico , Infecções Oportunistas Relacionadas com a AIDS/mortalidade , Síndrome da Imunodeficiência Adquirida/complicações , Adulto , Anfotericina B/uso terapêutico , Antirretrovirais/efeitos adversos , Antifúngicos/uso terapêutico , Causas de Morte , Otorreia de Líquido Cefalorraquidiano/imunologia , Esquema de Medicação , Feminino , Humanos , Contagem de Leucócitos , Masculino , Meningite Criptocócica/mortalidade , África do Sul/epidemiologia , Análise de Sobrevida , Uganda/epidemiologia
7.
RNA ; 21(10): 1757-69, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26249002

RESUMO

The RNA-binding protein, CELF1, binds to a regulatory sequence known as the GU-rich element (GRE) and controls a network of mRNA transcripts that regulate cellular activation, proliferation, and apoptosis. We performed immunoprecipitation using an anti-CELF1 antibody, followed by identification of copurified transcripts using microarrays. We found that CELF1 is bound to a distinct set of target transcripts in the H9 and Jurkat malignant T-cell lines, compared with primary human T cells. CELF1 was not phosphorylated in resting normal T cells, but in malignant T cells, phosphorylation of CELF1 correlated with its inability to bind to GRE-containing mRNAs that served as CELF1 targets in normal T cells. Lack of binding by CELF1 to these mRNAs in malignant T cells correlated with stabilization and increased expression of these transcripts. Several of these GRE-containing transcripts that encode regulators of cell growth were also stabilized and up-regulated in primary tumor cells from patients with T-cell acute lymphoblastic leukemia. Interestingly, transcripts encoding numerous suppressors of cell proliferation that served as targets of CELF1 in malignant T cells, but not normal T cells, exhibited accelerated degradation and reduced expression in malignant compared with normal T cells, consistent with the known function of CELF1 to mediate degradation of bound transcripts. Overall, CELF1 dysfunction in malignant T cells led to the up-regulation of a subset of GRE-containing transcripts that promote cell growth and down-regulation of another subset that suppress cell growth, producing a net effect that would drive a malignant phenotype.


Assuntos
Proteínas CELF1/metabolismo , Leucemia-Linfoma Linfoblástico de Células T Precursoras/metabolismo , RNA Mensageiro/metabolismo , Linfócitos T/metabolismo , Humanos , Fosforilação , Leucemia-Linfoma Linfoblástico de Células T Precursoras/patologia , Ligação Proteica
8.
PLoS Pathog ; 11(3): e1004701, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25764512

RESUMO

Pulmonary mycoses are often associated with type-2 helper T (Th2) cell responses. However, mechanisms of Th2 cell accumulation are multifactorial and incompletely known. To investigate Th2 cell responses to pulmonary fungal infection, we developed a peptide-MHCII tetramer to track antigen-specific CD4+ T cells produced in response to infection with the fungal pathogen Cryptococcus neoformans. We noted massive accruement of pathologic cryptococcal antigen-specific Th2 cells in the lungs following infection that was coordinated by lung-resident CD11b+ IRF4-dependent conventional dendritic cells. Other researchers have demonstrated that this dendritic cell subset is also capable of priming protective Th17 cell responses to another pulmonary fungal infection, Aspergillus fumigatus. Thus, higher order detection of specific features of fungal infection by these dendritic cells must direct Th2 cell lineage commitment. Since chitin-containing parasites commonly elicit Th2 responses, we hypothesized that recognition of fungal chitin is an important determinant of Th2 cell-mediated mycosis. Using C. neoformans mutants or purified chitin, we found that chitin abundance impacted Th2 cell accumulation and disease. Importantly, we determined Th2 cell induction depended on cleavage of chitin via the mammalian chitinase, chitotriosidase, an enzyme that was also prevalent in humans experiencing overt cryptococcosis. The data presented herein offers a new perspective on fungal disease susceptibility, whereby chitin recognition via chitotriosidase leads to the initiation of harmful Th2 cell differentiation by CD11b+ conventional dendritic cells in response to pulmonary fungal infection.


Assuntos
Quitina/imunologia , Criptococose/imunologia , Hexosaminidases/imunologia , Pneumopatias Fúngicas/imunologia , Células Th2/imunologia , Animais , Antígenos de Fungos/imunologia , Cryptococcus neoformans , Células Dendríticas/imunologia , Modelos Animais de Doenças , Citometria de Fluxo , Ativação Linfocitária/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Microscopia de Fluorescência
9.
BMC Neurol ; 17(1): 110, 2017 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-28606065

RESUMO

BACKGROUND: HIV-infected persons with detectable cryptococcal antigen (CrAg) in blood have increased morbidity and mortality compared with HIV-infected persons who are CrAg-negative. This study examined neurocognitive function among persons with asymptomatic cryptococcal antigenemia. METHODS: Participants from three prospective HIV cohorts underwent neurocognitive testing at the time of antiretroviral therapy (ART) initiation. Cohorts included persons with cryptococcal meningitis (N = 90), asymptomatic CrAg + (N = 87), and HIV-infected persons without central nervous system infection (N = 125). Z-scores for each neurocognitive test were calculated relative to an HIV-negative Ugandan population with a composite quantitative neurocognitive performance Z-score (QNPZ-8) created from eight tested domains. Neurocognitive function was measured pre-ART for all three cohorts and additionally after 4 weeks of ART (and 6 weeks of pre-emptive fluconazole) treatment among asymptomatic CrAg + participants. RESULTS: Cryptococcal meningitis and asymptomatic CrAg + participants had lower median CD4 counts (17 and 26 cells/µL, respectively) than the HIV-infected control cohort (233 cells/µL) as well as lower Karnofsky performance status (60 and 70 vs. 90, respectively). The composite QNPZ-8 for asymptomatic CrAg + (-1.80 Z-score) fell between the cryptococcal meningitis cohort (-2.22 Z-score, P = 0.02) and HIV-infected controls (-1.36, P = 0.003). After four weeks of ART and six weeks of fluconazole, the asymptomatic CrAg + cohort neurocognitive performance improved (-1.0 Z-score, P < 0.001). CONCLUSION: Significant deficits in neurocognitive function were identified in asymptomatic CrAg + persons with advanced HIV/AIDS even without signs or sequelae of meningitis. Neurocognitive function in this group improves over time after initiation of pre-emptive fluconazole treatment and ART, but short term adherence support may be necessary.


Assuntos
Cryptococcus/isolamento & purificação , Infecções por HIV/complicações , Meningite Criptocócica/diagnóstico , Adulto , Antígenos de Fungos/isolamento & purificação , Estudos de Coortes , Feminino , Humanos , Masculino , Estudos Prospectivos
11.
Med Mycol ; 54(3): 295-300, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26527637

RESUMO

Histoplasmosis is endemic to the Midwestern United States, but cases have been reported nearly worldwide. A 1970 study found 3.8% skin test sensitivity to Histoplasma capsulatum in Uganda but no systemic study of histoplasmosis exposure has occurred since the onset of the human immunodeficiency virus (HIV) pandemic. This study investigated the seroprevalence of H. capsulatum and sought previously undetected cases of histoplasmosis in Kampala, Uganda. Serum, cerebrospinal fluid (CSF) and/or urine specimens were obtained from HIV-infected persons with suspected meningitis. Specimens were tested for H. capsulatum IgG and IgM by enzyme immune assay and Histoplasma antigen. 147 of the 257 subjects who were enrolled had cryptococcal meningitis. Overall, 1.3% (2/151) of subjects were serum Histoplasma IgG positive, and zero of 151 were IgM positive. Antigen was not detected in any serum (n = 57), urine (n = 37, or CSF (n = 63) samples. Both subjects with serum Histoplasma IgG positivity had cryptococcal meningitis. Histoplasma capsulatum IgG was detected at low levels in persons with HIV/AIDS in Kampala, Uganda. Histoplasmosis is not widespread in Uganda but microfoci do exist. There appears to be no cross-reactivity between Cryptococcus neoformans and Histoplasma antigen testing, and cryptococcosis appears to be at most, a rare cause of positive Histoplasma IgG.


Assuntos
Histoplasmose/epidemiologia , Adulto , Anticorpos Antifúngicos/análise , Líquido Cefalorraquidiano/imunologia , Ensaio de Imunoadsorção Enzimática , Feminino , Infecções por HIV/complicações , Humanos , Imunoglobulina G/análise , Imunoglobulina M/análise , Masculino , Estudos Prospectivos , Estudos Soroepidemiológicos , Soro/imunologia , Uganda/epidemiologia , Urina/química
12.
J Infect Dis ; 211(10): 1597-606, 2015 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-25492918

RESUMO

BACKGROUND: Human immunodeficiency virus (HIV)-associated cryptococcal meningitis (CM) is characterized by high fungal burden and limited leukocyte trafficking to cerebrospinal fluid (CSF). The immunopathogenesis of CM immune reconstitution inflammatory syndrome (IRIS) after initiation of antiretroviral therapy at the site of infection is poorly understood. METHODS: We characterized the lineage and activation status of mononuclear cells in blood and CSF of HIV-infected patients with noncryptococcal meningitis (NCM) (n = 10), those with CM at day 0 (n = 40) or day 14 (n = 21) of antifungal therapy, and those with CM-IRIS (n = 10). RESULTS: At diagnosis, highly activated CD8(+) T cells predominated in CSF in both CM and NCM. CM-IRIS was associated with an increasing frequency of CSF CD4(+) T cells (increased from 2.2% to 23%; P = .06), a shift in monocyte phenotype from classic to an intermediate/proinflammatory, and increased programmed death ligand 1 expression on natural killer cells (increased from 11.9% to 61.6%, P = .03). CSF cellular responses were distinct from responses in peripheral blood. CONCLUSIONS: After CM, T cells in CSF tend to evolve with the development of IRIS, with increasing proportions of activated CD4(+) T cells, migration of intermediate monocytes to the CSF, and declining fungal burden. These changes provide insight into IRIS pathogenesis and could be exploited to more effectively treat CM and prevent CM-IRIS.


Assuntos
Antirretrovirais/uso terapêutico , Líquido Cefalorraquidiano/citologia , Infecções por HIV/complicações , Síndrome Inflamatória da Reconstituição Imune , Ativação Linfocitária , Meningite Criptocócica/imunologia , Meningite Criptocócica/patologia , Adulto , Antirretrovirais/efeitos adversos , Células Sanguíneas , Estudos de Coortes , Feminino , Infecções por HIV/tratamento farmacológico , Humanos , Subpopulações de Linfócitos/imunologia , Masculino , Estudos Prospectivos
13.
Biochim Biophys Acta ; 1829(6-7): 695-707, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23328451

RESUMO

The CELF family of RNA-binding proteins regulates many steps of mRNA metabolism. Although their best characterized function is in pre-mRNA splice site choice, CELF family members are also powerful modulators of mRNA decay. In this review we focus on the different modes of regulation that CELF proteins employ to mediate mRNA decay by binding to GU-rich elements. After starting with an overview of the importance of CELF proteins during development and disease pathogenesis, we then review the mRNA networks and cellular pathways these proteins regulate and the mechanisms by which they influence mRNA decay. Finally, we discuss how CELF protein activity is modulated during development and in response to cellular signals. We conclude by highlighting the priorities for new experiments in this field. This article is part of a Special Issue entitled: RNA Decay mechanisms.


Assuntos
Proteína delta de Ligação ao Facilitador CCAAT , Precursores de RNA/genética , Estabilidade de RNA/genética , RNA Mensageiro/genética , Processamento Alternativo , Animais , Proteína delta de Ligação ao Facilitador CCAAT/química , Proteína delta de Ligação ao Facilitador CCAAT/genética , Drosophila/genética , Exorribonucleases/genética , Humanos , Processamento de Proteína Pós-Traducional/genética , Precursores de RNA/química
14.
PLoS One ; 19(5): e0303805, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38771769

RESUMO

BACKGROUND: Cryptococcal meningitis (CM) remains a major cause of death among people living with HIV in rural sub-Saharan Africa. We previously reported that a CM diagnosis and treatment program (CM-DTP) improved hospital survival for CM patients in rural, northern Uganda. This study aimed to evaluate the impact on long-term survival. METHODS: We conducted a retrospective study at Lira Regional Referral Hospital in Uganda evaluating long-term survival (≥1 year) of CM patients diagnosed after CM-DTP initiation (February 2017-September 2021). We compared with a baseline historical group of CM patients before CM-DTP implementation (January 2015-February 2017). Using Cox proportional hazards models, we assessed time-to-death in these groups, adjusting for confounders. RESULTS: We identified 318 CM patients, 105 in the Historical Group, and 213 in the CM-DTP Group. The Historical Group had a higher 30-day mortality of 78.5% compared to 42.2% in the CM-DTP Group. The overall survival rate for the CM-DTP group at three years was 25.6%. Attendance at follow-up visits (HR:0.13, 95% CI: [0.03-0.53], p <0.001), ART adherence (HR:0.27, 95% CI: [0.10-0.71], p = 0.008), and fluconazole adherence: (HR:0.03, 95% CI: [0.01-0.13], p <0.001), weight >50kg (HR:0.54, 95% CI: [0.35-0.84], p = 0.006), and performance of therapeutic lumbar punctures (HR:0.42, 95% CI: [0.24-0.71], p = 0.001), were associated with lower risk of death. Altered mentation was associated with increased death risk (HR: 1.63, 95% CI: 1.10-2.42, p = 0.016). CONCLUSION: Long-term survival of CM patients improved after the initiation of the CM-DTP. Despite this improved survival, long-term outcomes remained sub-optimal, suggesting that further work is needed to enhance long-term survival.


Assuntos
Meningite Criptocócica , População Rural , Humanos , Uganda/epidemiologia , Meningite Criptocócica/mortalidade , Meningite Criptocócica/tratamento farmacológico , Feminino , Masculino , Adulto , Estudos Retrospectivos , Antifúngicos/uso terapêutico , Pessoa de Meia-Idade , Taxa de Sobrevida , Infecções por HIV/mortalidade , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Resultado do Tratamento , Modelos de Riscos Proporcionais
15.
J Biol Chem ; 287(2): 950-60, 2012 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-22117072

RESUMO

The RNA-binding protein, CUG-binding protein 1 (CUGBP1), regulates gene expression at the levels of alternative splicing, mRNA degradation, and translation. We used RNA immunoprecipitation followed by microarray analysis to identify the cytoplasmic mRNA targets of CUGBP1 in resting and activated primary human T cells and found that CUGBP1 targets were highly enriched for the presence of GU-rich elements (GREs) in their 3'-untranslated regions. The number of CUGBP1 target transcripts decreased dramatically following T cell activation as a result of activation-dependent phosphorylation of CUGBP1 and decreased ability of CUGBP1 to bind to GRE-containing RNA. A large percentage of CUGBP1 target transcripts exhibited rapid and transient up-regulation, and a smaller percentage exhibited transient down-regulation following T cell activation. Many of the transiently up-regulated CUGBP1 target transcripts encode important regulatory proteins necessary for transition from a quiescent state to a state of cellular activation and proliferation. Overall, our results show that CUGBP1 binding to certain GRE-containing target transcripts decreased following T cell activation through activation-dependent phosphorylation of CUGBP1.


Assuntos
Regiões 3' não Traduzidas/fisiologia , Ativação Linfocitária/fisiologia , Proteínas de Ligação a RNA/metabolismo , Proteínas CELF1 , Humanos , Fosforilação/fisiologia , Ligação Proteica/fisiologia , Proteínas de Ligação a RNA/genética , Linfócitos T
16.
Nurse Educ Today ; 128: 105873, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37390523

RESUMO

BACKGROUND: Cryptococcal meningitis (CM) is one of the deadliest opportunistic infections related to HIV/AIDS. A research gap exists surrounding the barriers to CM diagnosis, treatment delivery, and care from the healthcare provider's perspective. OBJECTIVES: The purpose of this study was to elucidate provider's behaviors, to identify barriers and facilitators to diagnose and treat CM, and to assess their knowledge of CM, cryptococcal screening, and treatment. DESIGN, SETTING, AND PARTICIPANTS: A convergent mixed-methods study among twenty healthcare providers who provided CM patient referrals to Lira Regional Referral Hospital in Lira, Uganda. METHODS: Surveys and interviews were conducted to obtain information from healthcare providers who referred CM patients to Lira Regional Referral Hospital from 2017 to 2019. Questions related to provider education, knowledge, barriers to CM care, and patient education were inquired to understand the providers' perspectives. RESULTS: Nurses had the least amount of CM knowledge with half knowing the cause of CM. Approximately half the participants knew about CM transmission, but only 15 % knew the duration of CM maintenance therapy. Most participants (74 %) last had education regarding CM during didactic training. In addition, 25 % disclosed they never educate patients due to time constraints (30 %) and lack of knowledge (30 %). Nurses (75 %) were least likely to provide patient education. Most participants acknowledged their lack of CM knowledge and attributed it to a lack of education and perceived inexperience with CM. CONCLUSIONS: Providers' gaps in knowledge due to the lack of education and experience contributes to decreased patient education, and the lack of access to appropriate supplies affects their provision for CM diagnosis, treatment, and care. These results can guide evidence-based interventions to improve health providers' knowledge. Recommendations for standardized CM education should be developed for both providers and patients in collaboration with professional boards and the Uganda Ministry of Health.


Assuntos
Meningite Criptocócica , Enfermeiras e Enfermeiros , Humanos , Meningite Criptocócica/diagnóstico , Uganda , Pessoal de Saúde , Pesquisa Qualitativa
17.
J Infect Dis ; 203(11): 1637-46, 2011 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-21592994

RESUMO

BACKGROUND: Substantial morbidity occurs during the first year of antiretroviral therapy (ART) in persons with advanced human immunodeficiency virus (HIV) disease despite HIV suppression. Biomarkers may identify high-risk groups. METHODS: Pre-ART and 1-month samples from an initial ART trial were evaluated for biomarkers associated with AIDS events or death within 1-12 months. Case patients (n = 63) and control patients (n = 126) were 1:2 matched on baseline CD4 cell count, hepatitis status, and randomization date. All had ≥ 1 log(10) HIV RNA level decrease at 1 month. RESULTS: Case patients had more frequent prior AIDS events, compared with control patients (P = .004), but similar HIV RNA levels at baseline. Pre-ART and 1-month C-reactive protein (CRP), D-dimer, and interleukin 6 (IL-6) levels and pre-ART hyaluronic acid (HA) levels were associated with new AIDS events or death (P ≤ .01). Patients who experienced immune reconstitution inflammatory syndrome (IRIS) events had higher pre-ART tumor necrosis factor α (TNF-α) and HIV RNA levels and significant 1-month increases in CRP, D-dimer, IL-6, interleukin 8, CXCL10, TNF-α, and interferon-γ levels, compared with patients who experienced non-IRIS events (P ≤ .03). Individuals with baseline CRP and HA levels above the cohort median (>2.1 mg/L and >50.0 ng/mL, respectively) had increased risk of AIDS or death (OR, 4.6 [95% CI, 2.0-10.3]; P < .001) and IRIS (OR, 8.7 [95% CI, 2.2-34.8] P = .002). CONCLUSIONS: Biomarkers of Inflammation (CRP, IL-6), coagulation (D-dimer), and tissue fibrosis (HA) measured pre-ART and at 1 month are associated with higher risk of AIDS events, IRIS, or death, warranting additional study as risk stratification strategies.


Assuntos
Síndrome da Imunodeficiência Adquirida/sangue , Proteína C-Reativa/metabolismo , Produtos de Degradação da Fibrina e do Fibrinogênio/metabolismo , Infecções por HIV/sangue , Infecções por HIV/tratamento farmacológico , Ácido Hialurônico/sangue , Interleucina-6/sangue , Síndrome da Imunodeficiência Adquirida/tratamento farmacológico , Adulto , Antirretrovirais/uso terapêutico , Biomarcadores/sangue , Biomarcadores/metabolismo , Estudos de Casos e Controles , Progressão da Doença , Feminino , Humanos , Síndrome Inflamatória da Reconstituição Imune/sangue , Síndrome Inflamatória da Reconstituição Imune/virologia , Masculino , Pessoa de Meia-Idade , Morbidade , RNA Viral/sangue , Fatores de Risco
18.
Artigo em Inglês | MEDLINE | ID: mdl-36713975

RESUMO

In rural areas of sub-Saharan Africa, infrastructure and resources for treatment of cryptococcal meningitis (CM) are often lacking. We introduced a CM diagnosis and treatment program (CM-DTP) at Lira Regional Referral Hospital (LRRH) in rural Uganda to determine if implementing high-quality standard of care protocols would improve outcomes. Information extracted from hospital charts and clinical record forms at LRRH were used to compare diagnoses, treatments, and outcomes for all patients diagnosed with meningitis (n = 281) over a two-year period after initiation of the CM-DTP in February of 2017 to all patients diagnosed with meningitis (n = 215) in the two preceding years. After implementation of the CM-DTP, we observed increased confirmed diagnoses of CM from 22.2% (48 of 215) to 35.2% (99 of 281), (p = 0.002) among all patients diagnosed with meningitis. Among all patients treated for CM, the proportion who received standard of care treatment with amphotericin B plus fluconazole increased from 63 of 127 (49.6%) to 109 of 146 (74.7%), (p <0.001) and mortality improved from 66 of 127 (52.0%) to 57 of 146 (39.0%), (p = 0.04) after implementation of the CM-DTP. Implementation of the CM-DTP was associated with increased number of lumbar punctures and decreased use of antibiotics in patients with CM, as well as decreased mortality among patients with meningitis from all causes. Improved diagnosis, treatment, and mortality were observed following implementation of the CM-DTP. Our results demonstrate that quality treatment of CM in rural Uganda is feasible.

19.
Open Forum Infect Dis ; 9(2): ofac004, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35111875

RESUMO

BACKGROUND: The impact of the "test and treat" program for human immunodeficiency virus (HIV) treatment in rural areas of Uganda on cryptococcal antigen (CrAg) screening or cryptococcal meningitis (CM) is poorly understood. METHODS: We retrospectively evaluated clinical factors in 212 HIV-infected patients diagnosed with CM from February of 2017 to November of 2019 at Lira Regional Referral Hospital in northern Uganda. RESULTS: Among 212 patients diagnosed with CM, 58.5% were male. Median age was 35 years; CD4 count and HIV viral load (VL) were 86 cells/µL and 9463 copies/mL, respectively. Only 10% of patients had a previous history of CM. We found that 190 of 209 (90.9%) patients were ART experienced and 19 (9.1%) were ART naive. Overall, 90 of 212 (42.5%) patients died while hospitalized (median time to death, 14 days). Increased risk of death was associated with altered mental status (hazard ratio [HR], 6.6 [95% confidence interval {CI}, 2.411-18.219]; P ≤ .0001) and seizures (HR, 5.23 [95% CI, 1.245-21.991]; P = .024). CONCLUSIONS: Current guidelines recommend CrAg screening based on low CD4 counts for ART-naive patients and VL or clinical failure for ART-experienced patients. Using current guidelines for CrAg screening, some ART-experienced patients miss CrAg screening in resource-limited settings, when CD4 or VL tests are unavailable. We found that the majority of HIV-infected patients with CM were ART experienced (90.9%) at presentation. The high burden of CM in ART-experienced patients supports a need for improved CrAg screening of ART-exposed patients.

20.
RNA Biol ; 8(4): 681-91, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21691152

RESUMO

Unlike AU-rich elements (AREs) that are largely present in the 3'UTRs of many unstable mammalian mRNAs, the function and abundance of GU-rich elements (GREs) are poorly understood. We performed a genome-wide analysis and found that at least 5% of human genes contain GREs in their 3'UTRs with functional over-representation in genes involved in transcription, nucleic acid metabolism, developmental processes, and neurogenesis. GREs have similar sequence clustering patterns with AREs such as overlapping GUUUG pentamers and enrichment in 3'UTRs. Functional analysis using T-cell mRNA expression microarray data confirms correlation with mRNA destabilization. Reporter assays show that compared to AREs the ability of GREs to destabilize mRNA is modest and does not increase with the increasing number of overlapping pentamers. Naturally occurring GREs within U-rich contexts were more potent in destabilizing GFP reporter mRNAs than synthetic GREs with perfectly overlapping pentamers. Overall, we find that GREs bear a resemblance to AREs in sequence patterns but they regulate a different repertoire of genes and have different dynamics of mRNA decay. A dedicated resource on all GRE-containing genes of the human, mouse and rat genomes can be found at brp.kfshrc.edu.sa/GredOrg.


Assuntos
Regiões 3' não Traduzidas , Regulação da Expressão Gênica , Genoma Humano , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transcriptoma , Sequência de Bases , Linhagem Celular , Guanina/química , Células HEK293 , Humanos , RNA Mensageiro/química , Uracila/química
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