Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 127
Filtrar
Más filtros

Banco de datos
Tipo del documento
Intervalo de año de publicación
1.
Blood ; 141(8): 904-916, 2023 02 23.
Artículo en Inglés | MEDLINE | ID: mdl-36201743

RESUMEN

Burkitt lymphoma (BL) accounts for most pediatric non-Hodgkin lymphomas, being less common but significantly more lethal when diagnosed in adults. Much of the knowledge of the genetics of BL thus far has originated from the study of pediatric BL (pBL), leaving its relationship to adult BL (aBL) and other adult lymphomas not fully explored. We sought to more thoroughly identify the somatic changes that underlie lymphomagenesis in aBL and any molecular features that associate with clinical disparities within and between pBL and aBL. Through comprehensive whole-genome sequencing of 230 BL and 295 diffuse large B-cell lymphoma (DLBCL) tumors, we identified additional significantly mutated genes, including more genetic features that associate with tumor Epstein-Barr virus status, and unraveled new distinct subgroupings within BL and DLBCL with 3 predominantly comprising BLs: DGG-BL (DDX3X, GNA13, and GNAI2), IC-BL (ID3 and CCND3), and Q53-BL (quiet TP53). Each BL subgroup is characterized by combinations of common driver and noncoding mutations caused by aberrant somatic hypermutation. The largest subgroups of BL cases, IC-BL and DGG-BL, are further characterized by distinct biological and gene expression differences. IC-BL and DGG-BL and their prototypical genetic features (ID3 and TP53) had significant associations with patient outcomes that were different among aBL and pBL cohorts. These findings highlight shared pathogenesis between aBL and pBL, and establish genetic subtypes within BL that serve to delineate tumors with distinct molecular features, providing a new framework for epidemiologic, diagnostic, and therapeutic strategies.


Asunto(s)
Linfoma de Burkitt , Infecciones por Virus de Epstein-Barr , Linfoma de Células B Grandes Difuso , Niño , Humanos , Adulto , Linfoma de Burkitt/patología , Herpesvirus Humano 4 , Linfoma de Células B Grandes Difuso/patología , Mutación
2.
PLoS Pathog ; 17(1): e1008594, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33465147

RESUMEN

Intra-host tumor virus variants may influence the pathogenesis and treatment responses of some virally-associated cancers. However, the intra-host variability of Kaposi sarcoma-associated herpesvirus (KSHV), the etiologic agent of Kaposi sarcoma (KS), has to date been explored with sequencing technologies that possibly introduce more errors than that which occurs in the viral population, and these studies have only studied variable regions. Here, full-length KSHV genomes in tumors and/or oral swabs from 9 Ugandan adults with HIV-associated KS were characterized. Furthermore, we used deep, short-read sequencing using duplex unique molecular identifiers (dUMI)-random double-stranded oligonucleotides that barcode individual DNA molecules before library amplification. This allowed suppression of PCR and sequencing errors to ~10-9/base as well as afforded accurate determination of KSHV genome numbers sequenced in each sample. KSHV genomes were assembled de novo, and rearrangements observed were confirmed by PCR and Sanger sequencing. 131-kb KSHV genome sequences, excluding major repeat regions, were successfully obtained from 23 clinical specimens, averaging 2.3x104 reads/base. Strikingly, KSHV genomes were virtually identical within individuals at the point mutational level. The intra-host heterogeneity that was observed was confined to tumor-associated KSHV mutations and genome rearrangements, all impacting protein-coding sequences. Although it is unclear whether these changes were important to tumorigenesis or occurred as a result of genomic instability in tumors, similar changes were observed across individuals. These included inactivation of the K8.1 gene in tumors of 3 individuals and retention of a region around the first major internal repeat (IR1) in all instances of genomic deletions and rearrangements. Notably, the same breakpoint junctions were found in distinct tumors within single individuals, suggesting metastatic spread of rearranged KSHV genomes. These findings define KSHV intra-host heterogeneity in vivo with greater precision than has been possible in the past and suggest the possibility that aberrant KSHV genomes may contribute to aspects of KS tumorigenesis. Furthermore, study of KSHV with use of dUMI provides a proof of concept for utilizing this technique for detailed study of other virus populations in vivo.


Asunto(s)
ADN Viral/análisis , Genoma Viral , Herpesvirus Humano 8/genética , Especificidad del Huésped , Sarcoma de Kaposi/virología , Adulto , Estudios de Cohortes , ADN Viral/genética , Femenino , Genómica , Herpesvirus Humano 8/clasificación , Herpesvirus Humano 8/aislamiento & purificación , Humanos , Masculino , Persona de Mediana Edad , Polimorfismo Genético , Sarcoma de Kaposi/epidemiología , Uganda/epidemiología
3.
PLoS Comput Biol ; 17(6): e1009072, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-34153032

RESUMEN

Epstein-Barr virus (EBV) is transmitted by saliva and is a major cause of cancer, particularly in people living with HIV/AIDS. Here, we describe the frequency and quantity of EBV detection in the saliva of Ugandan adults with and without HIV-1 infection and use these data to develop a novel mathematical model of EBV infection in the tonsils. Eligible cohort participants were not taking antiviral medications, and those with HIV-1 infection had a CD4 count >200 cells/mm3. Over a 4-week period, participants provided daily oral swabs that we analysed for the presence and quantity of EBV. Compared with HIV-1 uninfected participants, HIV-1 coinfected participants had an increased risk of EBV detection in their saliva (IRR = 1.27, 95% CI = 1.10-1.47) and higher viral loads in positive samples. We used these data to develop a stochastic, mechanistic mathematical model that describes the dynamics of EBV, infected cells, and immune response within the tonsillar epithelium to analyse potential factors that may cause EBV infection to be more severe in HIV-1 coinfected participants. The model, fit using Approximate Bayesian Computation, showed high fidelity to daily oral shedding data and matched key summary statistics. When evaluating how model parameters differed among participants with and without HIV-1 coinfection, results suggest HIV-1 coinfected individuals have higher rates of B cell reactivation, which can seed new infection in the tonsils and lower rates of an EBV-specific immune response. Subsequently, both these traits may explain higher and more frequent EBV detection in the saliva of HIV-1 coinfected individuals.


Asunto(s)
Coinfección/virología , Infecciones por Virus de Epstein-Barr/complicaciones , Infecciones por Virus de Epstein-Barr/virología , Infecciones por VIH/complicaciones , VIH-1 , Tonsila Palatina/virología , Adolescente , Adulto , Linfocitos B/inmunología , Estudios de Cohortes , Coinfección/inmunología , Biología Computacional , Infecciones por Virus de Epstein-Barr/inmunología , Femenino , Infecciones por VIH/inmunología , Herpesvirus Humano 4/inmunología , Herpesvirus Humano 4/aislamiento & purificación , Herpesvirus Humano 4/fisiología , Humanos , Inmunidad Celular , Masculino , Persona de Mediana Edad , Modelos Biológicos , Tonsila Palatina/inmunología , Saliva/virología , Procesos Estocásticos , Uganda , Carga Viral , Esparcimiento de Virus , Adulto Joven
4.
Semin Immunol ; 39: 22-29, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-30366662

RESUMEN

Lipopolysaccharide (LPS) is a well-defined agonist of Toll-like receptor (TLR) 4 that activates innate immune responses and influences the development of the adaptive response during infection with Gram-negative bacteria. Many years ago, Dr. Edgar Ribi separated the adjuvant activity of LPS from its toxic effects, an effort that led to the development of monophosphoryl lipid A (MPL). MPL, derived from Salmonella minnesota R595, has progressed through clinical development and is now used in various product-enabling formulations to support the generation of antigen-specific responses in several commercial and preclinical vaccines. We have generated several synthetic lipid A molecules, foremost glucopyranosyl lipid adjuvant (GLA) and second-generation lipid adjuvant (SLA), and have advanced these to clinical trial for various indications. In this review we summarize the potential and current positioning of TLR4-based adjuvant formulations in approved and emerging vaccines.


Asunto(s)
Adyuvantes Inmunológicos/farmacología , Compuestos de Alumbre/farmacología , Glucósidos/farmacología , Inmunogenicidad Vacunal , Lípido A/análogos & derivados , Tuberculosis/prevención & control , Adyuvantes Inmunológicos/química , Compuestos de Alumbre/química , Animales , Glucósidos/química , Infecciones por VIH/inmunología , Infecciones por VIH/prevención & control , Infecciones por VIH/virología , Humanos , Inmunidad Celular/efectos de los fármacos , Inmunidad Humoral/efectos de los fármacos , Leishmaniasis/inmunología , Leishmaniasis/parasitología , Leishmaniasis/prevención & control , Lepra/inmunología , Lepra/parasitología , Lepra/prevención & control , Lípido A/química , Lípido A/farmacología , Liposomas/administración & dosificación , Liposomas/química , Liposomas/inmunología , Malaria/inmunología , Malaria/parasitología , Malaria/prevención & control , Ratones , Esquistosomiasis/inmunología , Esquistosomiasis/parasitología , Esquistosomiasis/prevención & control , Linfocitos T Colaboradores-Inductores/efectos de los fármacos , Linfocitos T Colaboradores-Inductores/inmunología , Linfocitos T Colaboradores-Inductores/microbiología , Receptor Toll-Like 4/agonistas , Receptor Toll-Like 4/genética , Receptor Toll-Like 4/inmunología , Tuberculosis/inmunología , Tuberculosis/microbiología , Vacunas/administración & dosificación , Vacunas/química , Vacunas/inmunología
5.
J Infect Dis ; 223(11): 1897-1904, 2021 06 04.
Artículo en Inglés | MEDLINE | ID: mdl-33095855

RESUMEN

BACKGROUND: Epstein-Barr virus (EBV) infection is a major cause of malignancy worldwide. Maternal antibody is thought to prevent EBV infection because it is uncommon in early infancy. Maternal HIV infection is associated with an increased incidence of EBV infection in exposed infants, which we hypothesized results from impaired transfer of EBV-neutralizing maternal antibodies. METHODS: Among Ugandan infants followed for EBV acquisition from birth, we measured antibody binding to EBV glycoproteins (gp350, gH/gL) involved in B-cell and epithelial-cell entry, as well as viral neutralization and antibody-dependent cellular cytotoxicity (ADCC) activity in plasma samples prior to infection. These serologic data were analyzed for differences between HIV-exposed uninfected (HEU) and HIV-unexposed (HUU) infants, and for associations with incident infant EBV infection. RESULTS: HEU infants had significantly higher titers than HUU infants for all EBV-binding and neutralizing antibodies measured (P < .01) but not ADCC activity, which was similar between groups. No antibody measure was associated with a decreased risk of EBV acquisition in the cohort. CONCLUSIONS: Our findings indicate that in this cohort maternal antibody did not protect infants against EBV infection through viral neutralization. The identification of protective nonneutralizing antibody functions would be invaluable for the development of an EBV vaccine.


Asunto(s)
Anticuerpos Antivirales/inmunología , Infecciones por Virus de Epstein-Barr , Infecciones por VIH , Inmunidad Materno-Adquirida , Infecciones por Virus de Epstein-Barr/epidemiología , Femenino , Infecciones por VIH/complicaciones , Herpesvirus Humano 4 , Humanos , Lactante , Uganda/epidemiología
6.
Blood ; 133(12): 1313-1324, 2019 03 21.
Artículo en Inglés | MEDLINE | ID: mdl-30617194

RESUMEN

Although generally curable with intensive chemotherapy in resource-rich settings, Burkitt lymphoma (BL) remains a deadly disease in older patients and in sub-Saharan Africa. Epstein-Barr virus (EBV) positivity is a feature in more than 90% of cases in malaria-endemic regions, and up to 30% elsewhere. However, the molecular features of BL have not been comprehensively evaluated when taking into account tumor EBV status or geographic origin. Through an integrative analysis of whole-genome and transcriptome data, we show a striking genome-wide increase in aberrant somatic hypermutation in EBV-positive tumors, supporting a link between EBV and activation-induced cytidine deaminase (AICDA) activity. In addition to identifying novel candidate BL genes such as SIN3A, USP7, and CHD8, we demonstrate that EBV-positive tumors had significantly fewer driver mutations, especially among genes with roles in apoptosis. We also found immunoglobulin variable region genes that were disproportionally used to encode clonal B-cell receptors (BCRs) in the tumors. These include IGHV4-34, known to produce autoreactive antibodies, and IGKV3-20, a feature described in other B-cell malignancies but not yet in BL. Our results suggest that tumor EBV status defines a specific BL phenotype irrespective of geographic origin, with particular molecular properties and distinct pathogenic mechanisms. The novel mutation patterns identified here imply rational use of DNA-damaging chemotherapy in some patients with BL and targeted agents such as the CDK4/6 inhibitor palbociclib in others, whereas the importance of BCR signaling in BL strengthens the potential benefit of inhibitors for PI3K, Syk, and Src family kinases among these patients.


Asunto(s)
Biomarcadores de Tumor/genética , Linfoma de Burkitt/genética , Infecciones por Virus de Epstein-Barr/complicaciones , Genes de Inmunoglobulinas , Genoma Humano , Mutación , Transcriptoma , Adolescente , Adulto , Linfoma de Burkitt/patología , Linfoma de Burkitt/virología , Niño , Preescolar , Estudios de Cohortes , Citidina Desaminasa/genética , Infecciones por Virus de Epstein-Barr/genética , Infecciones por Virus de Epstein-Barr/virología , Femenino , Estudios de Seguimiento , Herpesvirus Humano 4/aislamiento & purificación , Humanos , Lactante , Recién Nacido , Masculino , Fenotipo , Pronóstico , Adulto Joven
7.
PLoS Pathog ; 14(12): e1007441, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30557332

RESUMEN

KSHV is endemic in Uganda and the HIV epidemic has dramatically increased the incidence of Kaposi sarcoma (KS). To investigate the role of KSHV in the development of KS, we obtained KS biopsies from ART-naïve, HIV-positive individuals in Uganda and analyzed the tumors using RNAseq to globally characterize the KSHV transcriptome. Phylogenetic analysis of ORF75 sequences from 23 tumors revealed 6 distinct genetic clusters with KSHV strains exhibiting M, N or P alleles. RNA reads mapping to specific unique coding sequence (UCDS) features were quantitated using a gene feature file previously developed to globally analyze and quantitate KSHV transcription in infected endothelial cells. A pattern of high level expression was detected in the KSHV latency region that was common to all KS tumors. The clear majority of transcription was derived from the downstream latency transcript promoter P3(LTd) flanking ORF72, with little evidence of transcription from the P1(LTc) latency promoter, which is constitutive in KSHV-infected lymphomas and tissue-culture cells. RNAseq data provided evidence of alternate P3(LTd) transcript editing, splicing and termination resulting in multiple gene products, with 90% of the P3(LTd) transcripts spliced to release the intronic source of the microRNAs K1-9 and 11. The spliced transcripts encode a regulatory uORF upstream of Kaposin A with alterations in intervening repeat sequences yielding novel or deleted Kaposin B/C-like sequences. Hierarchical clustering and PCA analysis of KSHV transcripts revealed three clusters of tumors with different latent and lytic gene expression profiles. Paradoxically, tumors with a latent phenotype had high levels of total KSHV transcription, while tumors with a lytic phenotype had low levels of total KSHV transcription. Morphologically distinct KS tumors from the same individual showed similar KSHV gene expression profiles suggesting that the tumor microenvironment and host response play important roles in the activation level of KSHV within the infected tumor cells.


Asunto(s)
Herpesvirus Humano 8/genética , Sarcoma de Kaposi/genética , Transcriptoma/genética , Latencia del Virus/genética , Perfilación de la Expresión Génica/métodos , Genes Virales/genética , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Humanos , Regiones Promotoras Genéticas/genética , Sarcoma de Kaposi/virología , Análisis de Secuencia de ARN , Uganda
8.
Blood ; 132(20): 2115-2124, 2018 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-30181172

RESUMEN

Castleman disease (CD) describes a group of heterogeneous hematologic disorders with characteristic histopathological features. CD can present with unicentric or multicentric (MCD) regions of lymph node enlargement. Some cases of MCD are caused by human herpesvirus-8 (HHV-8), whereas others are HHV-8-negative/idiopathic (iMCD). Treatment of iMCD is challenging, and outcomes can be poor because no uniform treatment guidelines exist, few systematic studies have been conducted, and no agreed upon response criteria have been described. The purpose of this paper is to establish consensus, evidence-based treatment guidelines based on the severity of iMCD to improve outcomes. An international Working Group of 42 experts from 10 countries was convened by the Castleman Disease Collaborative Network to establish consensus guidelines for the management of iMCD based on published literature, review of treatment effectiveness for 344 cases, and expert opinion. The anti-interleukin-6 monoclonal antibody siltuximab (or tocilizumab, if siltuximab is not available) with or without corticosteroids is the preferred first-line therapy for iMCD. In the most severe cases, adjuvant combination chemotherapy is recommended. Additional agents are recommended, tailored by disease severity, as second- and third-line therapies for treatment failures. Response criteria were formulated to facilitate the evaluation of treatment failure or success. These guidelines should help treating physicians to stratify patients based on disease severity in order to select the best available therapeutic option. An international registry for patients with CD (ACCELERATE, #NCT02817997) was established in October 2016 to collect patient outcomes to increase the evidence base for selection of therapies in the future.


Asunto(s)
Corticoesteroides/uso terapéutico , Anticuerpos Monoclonales/uso terapéutico , Antineoplásicos/uso terapéutico , Enfermedad de Castleman/tratamiento farmacológico , Anticuerpos Monoclonales Humanizados/uso terapéutico , Enfermedad de Castleman/patología , Enfermedad de Castleman/terapia , Ensayos Clínicos como Asunto , Enfermedad Crítica/terapia , Manejo de la Enfermedad , Medicina Basada en la Evidencia , Humanos , Guías de Práctica Clínica como Asunto
9.
J Infect Dis ; 220(5): 772-780, 2019 07 31.
Artículo en Inglés | MEDLINE | ID: mdl-31107951

RESUMEN

BACKGROUND: Development of a cytomegalovirus (CMV) vaccine is a high priority. However, the ability of antibodies to protect against CMV infection is not well characterized. Studies of maternal antibodies in infants offer the potential to identify humoral correlates of protection against postnatal acquisition. METHODS: This hypothesis-generating study analyzed 29 Ugandan mother-infant pairs that were followed weekly for CMV acquisition. Seventeen mothers and no infants were infected with human immunodeficiency virus (HIV). We evaluated the association between CMV-specific immunoglobulin G (IgG) responses in mothers at the time of delivery and their infants' CMV status at 6 months of age. We also assessed levels of CMV-specific IgG in infants at 6 weeks of age. CMV-specific IgG responses in the mother-infant pairs were then analyzed on the basis of perinatal HIV exposure. RESULTS: We found similar levels of multiple CMV glycoprotein-specific IgG binding specificities and functions in mothers and infants, irrespective of perinatal HIV exposure or infant CMV status at 6 months of age. However, the glycoprotein B-specific IgG titer, measured by 2 distinct assays, was higher in infants without CMV infection and was moderately associated with delayed CMV acquisition. CONCLUSIONS: These data suggest that high levels of glycoprotein B-specific IgG may contribute to the partial protection against postnatal CMV infection afforded by maternal antibodies, and they support the continued inclusion of glycoprotein B antigens in CMV vaccine candidates.


Asunto(s)
Infecciones por Citomegalovirus/inmunología , Infecciones por Citomegalovirus/prevención & control , Vacunas contra Citomegalovirus/inmunología , Citomegalovirus/inmunología , Inmunidad Humoral , Transmisión Vertical de Enfermedad Infecciosa/prevención & control , Anticuerpos Antivirales/inmunología , Formación de Anticuerpos , Infecciones por VIH/complicaciones , Humanos , Inmunoglobulina G/inmunología , Inmunoglobulinas Intravenosas , Lactante , Madres , Uganda , Proteínas del Envoltorio Viral/inmunología
10.
Cancer ; 125(11): 1918-1928, 2019 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-30840316

RESUMEN

BACKGROUND: Perceptions of high cost and resource intensity remain political barriers to the prioritization of childhood cancer treatment programs in many low- and middle-income countries (LMICs). Little knowledge exists of the actual cost and cost-effectiveness of such programs. To improve outcomes for children with Burkitt lymphoma (BL), the most common childhood cancer in Africa, the Uganda Cancer Institute implemented a comprehensive BL treatment program in 2012. We undertook an economic evaluation of the program to ascertain the cost-effectiveness of BL therapy in a specific LIC setting. METHODS: We compared the treatment of BL to usual care in a cohort of 122 patients treated between 2012 and 2014. Costs included variable, fixed, and family costs. Our primary measure of effectiveness was overall survival (OS). Patient outcomes were determined through prospective capture and retrospective chart abstraction. The cost per disability-adjusted life-year (DALY) averted was calculated using the World Health Organization's Choosing Interventions That Are Cost-Effective (WHO-CHOICE) methodology. RESULTS: The 2-year OS with treatment was 55% (95% CI, 45% to 64%). The cost per DALY averted in the treatment group was US$97 (Int$301). Cumulative estimate of national DALYs averted through treatment was 8607 years, and the total national annual cost of treatment was US$834,879 (Int$2,590,845). The cost of BL treatment fell well within WHO-CHOICE cost-effectiveness thresholds. The ratio of cost per DALY averted to per capita gross domestic product was 0.14, reflecting a very cost-effective intervention. CONCLUSION: This study demonstrates that treating BL with locally tailored protocols is very cost-effective by international standards. Studies of this kind will furnish crucial evidence to help policymakers prioritize the allocation of LMIC health system resources among noncommunicable diseases, including childhood cancer.


Asunto(s)
Antineoplásicos/uso terapéutico , Linfoma de Burkitt/tratamiento farmacológico , Linfoma de Burkitt/economía , Antineoplásicos/economía , Niño , Análisis Costo-Beneficio , Femenino , Humanos , Masculino , Estudios Prospectivos , Años de Vida Ajustados por Calidad de Vida , Estudios Retrospectivos , Análisis de Supervivencia , Resultado del Tratamiento , Uganda
11.
Blood ; 129(12): 1646-1657, 2017 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-28087540

RESUMEN

Human herpesvirus-8 (HHV-8)-negative, idiopathic multicentric Castleman disease (iMCD) is a rare and life-threatening disorder involving systemic inflammatory symptoms, polyclonal lymphoproliferation, cytopenias, and multiple organ system dysfunction caused by a cytokine storm often including interleukin-6. iMCD accounts for one third to one half of all cases of MCD and can occur in individuals of any age. Accurate diagnosis is challenging, because no standard diagnostic criteria or diagnostic biomarkers currently exist, and there is significant overlap with malignant, autoimmune, and infectious disorders. An international working group comprising 34 pediatric and adult pathology and clinical experts in iMCD and related disorders from 8 countries, including 2 physicians that are also iMCD patients, was convened to establish iMCD diagnostic criteria. The working group reviewed data from 244 cases, met twice, and refined criteria over 15 months (June 2015 to September 2016). The proposed consensus criteria require both Major Criteria (characteristic lymph node histopathology and multicentric lymphadenopathy), at least 2 of 11 Minor Criteria with at least 1 laboratory abnormality, and exclusion of infectious, malignant, and autoimmune disorders that can mimic iMCD. Characteristic histopathologic features may include a constellation of regressed or hyperplastic germinal centers, follicular dendritic cell prominence, hypervascularization, and polytypic plasmacytosis. Laboratory and clinical Minor Criteria include elevated C-reactive protein or erythrocyte sedimentation rate, anemia, thrombocytopenia or thrombocytosis, hypoalbuminemia, renal dysfunction or proteinuria, polyclonal hypergammaglobulinemia, constitutional symptoms, hepatosplenomegaly, effusions or edema, eruptive cherry hemangiomatosis or violaceous papules, and lymphocytic interstitial pneumonitis. iMCD consensus diagnostic criteria will facilitate consistent diagnosis, appropriate treatment, and collaborative research.


Asunto(s)
Enfermedad de Castleman/diagnóstico , Enfermedad de Castleman/etiología , Herpesvirus Humano 8 , Consenso , Diagnóstico Diferencial , Humanos , Internacionalidad , Guías de Práctica Clínica como Asunto
12.
Pediatr Blood Cancer ; 66(9): e27813, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31157502

RESUMEN

PURPOSE: "Endemic" Burkitt lymphoma (BL) is a common childhood cancer in Africa. Social and treatment factors may contribute to poor survival. With the aim of improving BL outcomes in Uganda, we undertook a comprehensive project (BL Project) that provided diagnostic support, access to standard chemotherapy, nutritional evaluations, and case management. We evaluated survival of children with BL in the context of the project. PATIENTS AND METHODS: Patients followed by the BL Project who consented to research were enrolled in this study. Children with a pathology diagnosis consistent with BL were eligible. Data were collected prospectively. First-line chemotherapy generally consisted of six cycles of cyclophosphamide, vincristine, low-dose methotrexate (COM). We used Kaplan-Meier and Cox regression analyses to evaluate factors associated with overall survival (OS). RESULTS: Between July 2012 and June 2017, 341 patients with suspected BL presented to the BL Project. One hundred eighty patients with a pathology-based diagnosis were included in this study. The median age was seven years (interquartile range, 5-9), 74% lived ≥100 km from the Uganda Cancer Institute, 61% had late-stage disease, 84% had ECOG performance status < 3, 63% reported B-symptoms, and 22% showed neurologic symptoms. Fewer than 10% abandoned therapy. The four-year OS rate was 44% (95% CI, 36%-53%). In a multivariate model, ECOG status was significantly associated with mortality. CONCLUSION: The BL Project reduced effects of lacking supportive care and oncology resources, and allowed patients from Uganda to receive curative intent therapy with minimal loss to follow-up. Nonetheless, OS remains unacceptably low. Improved therapeutic approaches to endemic BL are urgently needed in Africa.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Linfoma de Burkitt/tratamiento farmacológico , Linfoma de Burkitt/mortalidad , Niño , Preescolar , Ciclofosfamida/administración & dosificación , Supervivencia sin Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Masculino , Metotrexato/administración & dosificación , Estudios Prospectivos , Tasa de Supervivencia , Uganda/epidemiología , Vincristina/administración & dosificación
13.
J Virol ; 91(12)2017 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-28381570

RESUMEN

Cytomegalovirus (CMV) is acquired by the oral route in children, and primary infection is associated with abundant mucosal replication, as well as the establishment of latency in myeloid cells that results in lifelong infection. The efficiency of primary CMV infection in humans following oral exposure, however, is unknown. We consistently detected self-limited, low-level oral CMV shedding events, which we termed transient CMV infections, in a prospective birth cohort of 30 highly exposed CMV-uninfected infants. We estimated the likelihood of transient oral CMV infections by comparing their observed frequency to that of established primary infections, characterized by persistent high-level shedding, viremia, and seroconversion. We developed mathematical models of viral dynamics upon initial oral CMV infection and validated them using clinical shedding data. Transient infections comprised 76 to 88% of oral CMV shedding events. For this high percentage of transient infections to occur, we identified two mathematical prerequisites: a very small number of initially infected oral cells (1 to 4) and low viral infectivity (<1.5 new cells infected/cell). These observations indicate that oral CMV infection in infants typically begins with a single virus that spreads inefficiently to neighboring cells. Thus, although the incidence of CMV infection is high during infancy, our data provide a mechanistic framework to explain why multiple CMV exposures are typically required before infection is successfully established. These findings imply that a sufficiently primed immune response could prevent CMV from establishing latent infection in humans and support the achievability of a prophylactic CMV vaccine.IMPORTANCE CMV infects the majority of the world's population and is a major cause of birth defects. Developing a vaccine to prevent CMV infection would be extremely valuable but would be facilitated by a better understanding of how natural human CMV infection is acquired. We studied CMV acquisition in infants and found that infections are usually brief and self-limited and are successfully established relatively rarely. Thus, although most people eventually acquire CMV infection, it usually requires numerous exposures. Our analyses indicate that this is because the virus is surprisingly inefficient, barely replicating well enough to spread to neighboring cells in the mouth. Greater knowledge of why CMV infection usually fails may provide insight into how to prevent it from succeeding.


Asunto(s)
Citomegalovirus/fisiología , Boca/virología , Esparcimiento de Virus , Niño , Preescolar , Infecciones por Citomegalovirus/transmisión , Infecciones por Citomegalovirus/virología , Femenino , Humanos , Lactante , Masculino , Modelos Teóricos , Estudios Prospectivos , Seroconversión , Uganda , Viremia , Latencia del Virus , Replicación Viral
14.
J Infect Dis ; 216(2): 198-202, 2017 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-28838145

RESUMEN

Epstein-Barr virus (EBV) causes infectious mononucleosis and can lead to lymphoproliferative diseases. We evaluated the effects of valganciclovir on oral EBV shedding in a randomized, double-blind, placebo-controlled study. Twenty-six men received oral valganciclovir or daily placebo for 8 weeks, followed by a 2-week "washout period" and then 8 weeks of the alternative treatment. Valganciclovir reduced the proportion of days with EBV detected from 61.3% to 17.8% (relative risk, 0.28; 95% confidence interval [CI], .21-.41; P < .001), and quantity of virus detected by 0.77 logs (95% CI, .62-.91 logs; P < .001). Further investigations into the impact of valganciclovir on EBV-associated diseases are needed.


Asunto(s)
Antivirales/administración & dosificación , Ganciclovir/análogos & derivados , Mononucleosis Infecciosa/tratamiento farmacológico , Replicación Viral/efectos de los fármacos , Esparcimiento de Virus/efectos de los fármacos , Adulto , Anciano , Método Doble Ciego , Ganciclovir/administración & dosificación , Herpesvirus Humano 4/fisiología , Humanos , Masculino , Persona de Mediana Edad , Valganciclovir , Carga Viral/efectos de los fármacos , Washingtón , Adulto Joven
15.
Brain Behav Immun ; 66: 156-164, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28676350

RESUMEN

Cytokines, including interleukin-6 (IL-6), modulate neuronal plasticity and stress coping. Depressive symptoms and major depressive disorder (MDD) have been associated with changes in cytokines and their signaling. The current study examined the effect of IL-6 monoclonal antibody administration on depressive symptoms in patients with rheumatoid arthritis (RA) or multicentric Castleman's disease (MCD). The data were obtained from two phase 2, double-blind, placebo-controlled trials designed to test the efficacy of sirukumab in RA (N=176) or of siltuximab in MCD (N=65), and were analyzed post hoc to investigate the effects of these IL-6 antibodies on depressive symptoms. The SF-36 questionnaire items on depressed-mood and anhedonia were combined as the measure for depressive symptoms. The study participants were grouped by the presence/absence of prevalent depressed mood and anhedonia (PDMA, meaning either depressed mood or anhedonia was present at least 'most of the time' and the other at least 'some of the time' for four weeks) at baseline; 26.1% of the RA sample and 15.4% of the MCD sample met criteria for PDMA at baseline. Compared with placebo, sirukumab and siltuximab produced significantly greater improvements on depressive symptoms. To account for an effect on mood due to changes in RA or MCD, the analysis was (1) adjusted for symptom severities using DAS28-CRP for RA and MCDOS for MCD alone or together with bodily pain and physical functioning, and (2) performed within RA and MCD non-responders. Improvement in depressive symptoms remained significant in the treated group for both drugs. The significance over placebo was also observed in the siltuximab study. The improvement in depressive symptoms by sirukumab correlated positively with the baseline soluble IL-6 receptor levels. The data together suggest that the IL-6 antibodies improve depressive symptoms in patients with RA and MCD. Further studies are needed to elucidate to what extents the IL-6 antibodies improve depressive symptoms through improving primary disease dependent and independent mechanisms, especially in RA patients, and the brain mechanisms underlying depressive symptom improvements.


Asunto(s)
Anhedonia , Anticuerpos Monoclonales/uso terapéutico , Antidepresivos/uso terapéutico , Artritis Reumatoide/tratamiento farmacológico , Enfermedad de Castleman/tratamiento farmacológico , Depresión/tratamiento farmacológico , Interleucina-6/inmunología , Anticuerpos Monoclonales Humanizados , Artritis Reumatoide/complicaciones , Biomarcadores/sangre , Enfermedad de Castleman/complicaciones , Depresión/sangre , Depresión/complicaciones , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Resultado del Tratamiento
16.
J Natl Compr Canc Netw ; 15(4): 457-464, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-28404756

RESUMEN

Background: Patients with cancer are at high risk for severe sepsis and septic shock (SS/SSh), and a delay in receiving effective antibiotics is strongly associated with mortality. Delays are due to logistics of clinic flow and drug delivery. In an era of increasing antimicrobial resistance, combination therapy may be superior to monotherapy for patients with SS/SSh. Patients and Methods: At the Seattle Cancer Care Alliance, we implemented the Sepsis STAT Pack (SSP) program to simplify timely and effective provision of empiric antibiotics and other resuscitative care to outpatients with cancer with suspected SS/SSh before hospitalization. Over a 49-month period from January 1, 2008, through January 31, 2012, a total of 162 outpatients with cancer received the intervention. A retrospective cohort study was conducted to determine outcomes, including mortality and adverse events associated with the use of a novel care bundle designed for compatibility of broad-spectrum antibiotics and other supportive care administered concurrently via rapid infusion at fixed doses. Results: Of 162 sequential patients with cancer and suspected SS/SSh who received the SSP, 71 (44%) were diagnosed with SS/SSh. Median age was 53 years and 65% were men; 141 (87%) had hematologic malignancies, 77 (48%) were transplant recipients, and 80 (49%) were neutropenic. Median time to completion of antibiotics was 111 minutes (interquartile range, 60-178 minutes). A total of 71 patients (44%) had bacteremia and 17% of 93 isolates were multidrug-resistant. Possibly related nephrotoxicity occurred in 7 patients, and 30-day mortality occured in 6 of 160 patients (4%), including 3 of 71 (4%) with SS/SSh. Risk of developing SSh or death within 30 days increased 18% (95% CI, 4%-34%) for each hour delay to completion of antibiotics (P=.01). Conclusions: Rapidly administered combination antibiotics and supportive care delivered emergently to ambulatory patients with cancer with suspected SS/SSh was well-tolerated and associated with excellent short-term survival.


Asunto(s)
Antibacterianos/administración & dosificación , Neoplasias/complicaciones , Sepsis/tratamiento farmacológico , Sepsis/etiología , Choque Séptico/tratamiento farmacológico , Choque Séptico/etiología , Adulto , Profilaxis Antibiótica , Femenino , Terapia de Infusión a Domicilio , Humanos , Infusiones Intravenosas , Masculino , Persona de Mediana Edad , Mortalidad , Neoplasias/diagnóstico , Neoplasias/terapia , Sepsis/diagnóstico , Sepsis/mortalidad , Índice de Severidad de la Enfermedad , Choque Séptico/diagnóstico , Choque Séptico/mortalidad , Tiempo de Tratamiento , Resultado del Tratamiento
17.
J Infect Dis ; 214(11): 1735-1743, 2016 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-27651417

RESUMEN

Cytomegalovirus (CMV) infection occurs frequently in young children, who, when infected, are then a major source of transmission. Oral CMV shedding by 14 infants with primary infection was comprehensively characterized using quantitative polymerase chain reaction weekly for ≥9 months. Three phases of oral shedding were identified: expansion, transition, and clearance. Viral expansion occurred over a median of 7 weeks, with a median doubling time of 3 days. During the transition phase, expansion slowed over a median of 6 weeks before peak viral load was reached. Clearance was slow (22-day median half-life), and shedding did not resolve during observation for any infant. Mathematical modeling demonstrated that prolonged oral CMV expansion is explained by a low within-host reproduction number (median, 1.63) and a delayed immune response that only decreases the infected cell half-life by 44%. Thus, the prolonged oral CMV shedding observed during primary infection can be explained by slow viral expansion and inefficient immunologic control.


Asunto(s)
Infecciones por Citomegalovirus/patología , Infecciones por Citomegalovirus/virología , Citomegalovirus/aislamiento & purificación , Boca/virología , Esparcimiento de Virus , Preescolar , Estudios de Cohortes , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Modelos Teóricos , Embarazo , Reacción en Cadena en Tiempo Real de la Polimerasa , Factores de Tiempo , Uganda
18.
J Infect Dis ; 213(3): 439-47, 2016 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-26486633

RESUMEN

BACKGROUND: Despite the high prevalence of herpes simplex virus type 2 (HSV-2) in sub-Saharan Africa, the natural history of infection among Africans is not well characterized. We evaluated the frequency of genital HSV shedding in HIV-seropositive and HIV-seronegative men and women in Uganda. METHODS: Ninety-three HSV-2-seropositive Ugandan adults collected anogenital swab specimens for HSV DNA quantification by polymerase chain reaction 3 times daily for 6 weeks. RESULTS: HSV-2 was detected from 2484 of 11 283 swab specimens collected (22%), with a median quantity of 4.3 log10 HSV copies/mL (range, 2.2-8.9 log10 HSV copies/mL). Genital lesions were reported on 749 of 3875 days (19%), and subclinical HSV shedding was detected from 1480 of 9113 swab specimens (16%) collected on days without lesions. Men had higher rates of total HSV shedding (relative risk [RR], 2.0 [95% confidence interval {CI}, 1.3-2.9]; P < .001); subclinical shedding (RR, 1.7 [95% CI, 1.1-2.7]; P = .01), and genital lesions (RR, 2.1 [95% CI, 1.2-3.4]; P = .005), compared with women. No differences in shedding rates or lesion frequency were observed based on HIV serostatus. CONCLUSIONS: HSV-2 shedding frequency and quantity are high among HSV-2-seropositive adults in sub-Saharan Africa, including persons with and those without HIV infection. Shedding rates were particularly high among men, which may contribute to the high prevalence of HSV-2 and early acquisition among African women.


Asunto(s)
Infecciones por VIH/complicaciones , Herpes Genital/virología , Herpesvirus Humano 2/fisiología , Simplexvirus/fisiología , Esparcimiento de Virus/fisiología , Adolescente , Adulto , Anciano , ADN Viral/genética , Femenino , Infecciones por VIH/epidemiología , Herpes Genital/complicaciones , Herpes Genital/epidemiología , Herpesvirus Humano 2/genética , Humanos , Masculino , Persona de Mediana Edad , Uganda/epidemiología , Adulto Joven
19.
J Infect Dis ; 214(1): 36-44, 2016 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-26917575

RESUMEN

BACKGROUND: Human herpesvirus (HHV) infections are common during infancy. Primary infections are frequently asymptomatic and best studied prospectively by using direct viral detection. METHODS: Oropharyngeal swab specimens were collected weekly from Ugandan newborn infants, their mothers, and other children in the household. Blood specimens were collected every 4 months. Samples were tested for herpes simplex virus (HSV) types 1 and 2, Epstein-Barr virus (EBV), cytomegalovirus (CMV), HHV-6A, HHV-6B, and HHV-8, using quantitative polymerase chain reaction. RESULTS: Thirty-two infants, 32 mothers, and 49 other household children were followed for a median of 57 weeks. Seventeen mothers had human immunodeficiency virus type 1 (HIV) infection; no infants acquired HIV-1. The 12-month incidence of postnatal infection was 76% for HHV-6B, 59% for CMV, 47% for EBV, 8% for HSV-1, and 0% for HHV-8. The quantity of oropharyngeal shedding by contacts was associated with HHV-6A or HHV-6B transmission. Maternal HIV-1 infection was associated with EBV transmission, while breastfeeding and younger child contacts were associated with CMV transmission. Except for HSV-1, primary HHV infections were subclinical. CONCLUSIONS: By capturing exposures and acquisition events, we found that the incidence and risk factors of infection vary by HHV type. HSV-1 infection, unlike other HHV infections, caused acute clinical illness in these infants.


Asunto(s)
Infecciones por Herpesviridae/sangre , Infecciones por Herpesviridae/transmisión , Herpesviridae/aislamiento & purificación , Adolescente , Adulto , Niño , Preescolar , Estudios de Cohortes , Femenino , Infecciones por Herpesviridae/epidemiología , Infecciones por Herpesviridae/fisiopatología , Humanos , Incidencia , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Factores de Riesgo , Uganda/epidemiología
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA