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1.
Radiology ; 310(1): e232007, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38289209

RESUMO

The CT Colonography Reporting and Data System (C-RADS) has withstood the test of time and proven to be a robust classification scheme for CT colonography (CTC) findings. C-RADS version 2023 represents an update on the scheme used for colorectal and extracolonic findings at CTC. The update provides useful insights gained since the implementation of the original system in 2005. Increased experience has demonstrated confusion on how to classify the mass-like appearance of the colon consisting of soft tissue attenuation that occurs in segments with acute or chronic diverticulitis. Therefore, the update introduces a new subcategory, C2b, specifically for mass-like diverticular strictures, which are likely benign. Additionally, the update simplifies extracolonic classification by combining E1 and E2 categories into an updated extracolonic category of E1/E2 since, irrespective of whether a finding is considered a normal variant (category E1) or an otherwise clinically unimportant finding (category E2), no additional follow-up is required. This simplifies and streamlines the classification into one category, which results in the same management recommendation.


Assuntos
Colonografia Tomográfica Computadorizada , Divertículo , Humanos , Confusão , Constrição Patológica
2.
J Infect Dis ; 225(10): 1731-1740, 2022 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-34962990

RESUMO

BACKGROUND: Recent studies have indicated that broadly neutralizing antibodies (bnAbs) in children may develop earlier after human immunodeficiency virus (HIV) infection compared to adults. METHODS: We evaluated plasma from 212 antiretroviral therapy-naive children with HIV (1-3 years old). Neutralization breadth and potency was assessed using a panel of 10 viruses and compared to adults with chronic HIV. The magnitude, epitope specificity, and immunoglobulin (Ig)G subclass distribution of Env-specific antibodies were assessed using a binding antibody multiplex assay. RESULTS: One-year-old children demonstrated neutralization breadth comparable to chronically infected adults, whereas 2- and 3-year-olds exhibited significantly greater neutralization breadth (P = .014). Likewise, binding antibody responses increased with age, with levels in 2- and 3-year-old children comparable to adults. Overall, there was no significant difference in antibody specificities or IgG subclass distribution between the pediatric and adult cohorts. It is interesting to note that the neutralization activity was mapped to a single epitope (CD4 binding site, V2 or V3 glycans) in only 5 of 38 pediatric broadly neutralizing samples, which suggests that most children may develop a polyclonal neutralization response. CONCLUSIONS: These results contribute to a growing body of evidence suggesting that initiating HIV immunization early in life may present advantages for the development of broadly neutralizing antibody responses.


Assuntos
Infecções por HIV , HIV-1 , Adulto , Anticorpos Neutralizantes , Anticorpos Amplamente Neutralizantes , Criança , Pré-Escolar , Epitopos , Anticorpos Anti-HIV , Humanos , Imunoglobulina G , Lactente
3.
J Infect Dis ; 226(12): 2069-2078, 2022 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-35732186

RESUMO

BACKGROUND: This United States-based study compared 2 candidate vaccines: RSV/ΔNS2/Δ1313/I1314L, attenuated by NS2 gene-deletion and temperature-sensitivity mutation in the polymerase gene; and RSV/276, attenuated by M2-2 deletion. METHODS: RSV-seronegative children aged 6-24 months received RSV/ΔNS2/Δ1313/I1314L (106 plaque-forming units [PFU]), RSV/276 (105 PFU), or placebo intranasally. Participants were monitored for vaccine shedding, reactogenicity, and RSV serum antibodies, and followed over the subsequent RSV season. RESULTS: Enrollment occurred September 2017 to October 2019. During 28 days postinoculation, upper respiratory illness and/or fever occurred in 64% of RSV/ΔNS2/Δ1313/I1314L, 84% of RSV/276, and 58% of placebo recipients. Symptoms were generally mild. Cough was more common in RSV/276 recipients than RSV/ΔNS2/Δ1313/I1314L (48% vs 12%; P = .012) or placebo recipients (17%; P = .084). There were no lower respiratory illness or serious adverse events. Eighty-eight and 96% of RSV/ΔNS2/Δ1313/I1314L and RSV/276 recipients were infected with vaccine (shed vaccine and/or had ≥4-fold rises in RSV antibodies). Serum RSV-neutralizing titers and anti-RSV F IgG titers increased ≥4-fold in 60% and 92% of RSV/ΔNS2/Δ1313/I1314L and RSV/276 vaccinees, respectively. Exposure to community RSV during the subsequent winter was associated with strong anamnestic RSV-antibody responses. CONCLUSIONS: Both vaccines had excellent infectivity and were well tolerated. RSV/276 induced an excess of mild cough. Both vaccines were immunogenic and primed for strong anamnestic responses. CLINICAL TRIALS REGISTRATION: NCT03227029 and NCT03422237.


Assuntos
Infecções por Vírus Respiratório Sincicial , Vacinas contra Vírus Sincicial Respiratório , Vírus Sincicial Respiratório Humano , Criança , Humanos , Anticorpos Neutralizantes , Anticorpos Antivirais , Tosse , Vacinas contra Vírus Sincicial Respiratório/efeitos adversos , Vacinas contra Vírus Sincicial Respiratório/genética , Vírus Sinciciais Respiratórios , Vacinas Atenuadas/efeitos adversos , Vacinas Atenuadas/genética
4.
Am J Respir Crit Care Med ; 203(5): 594-603, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-32871092

RESUMO

Rationale: Active immunization is needed to protect infants and young children against respiratory syncytial virus (RSV). Rationally designed live-attenuated RSV vaccines are in clinical development.Objectives: Develop preliminary estimates of vaccine efficacy, assess durability of antibody responses to vaccination and "booster" responses after natural RSV infection, and determine sample sizes needed for more precise estimates of vaccine efficacy.Methods: We analyzed data from seven phase 1 trials of live-attenuated RSV vaccines in 6- to 24-month-old children (n = 239).Measurements and Main Results: The five vaccine regimens that induced neutralizing antibody responses in ≥80% of vaccinees (defined post hoc as "more promising") protected against RSV-associated medically attended acute respiratory illness (RSV-MAARI) and medically attended acute lower respiratory illness (RSV-MAALRI) and primed for potent anamnestic responses upon natural exposure to wild-type RSV. Among recipients of "more promising" RSV vaccines, efficacy against RSV-MAARI was 67% (95% confidence interval [CI], 24 to 85; P = 0.008) and against RSV-MAALRI was 88% (95% CI, -9 to 99; P = 0.04). A greater than or equal to fourfold increase in RSV serum neutralizing antibody following vaccination was strongly associated with protection against RSV-MAARI (odds ratio, 0.26; 95% CI, 0.09 to 0.75; P = 0.014) and RSV-MAALRI; no child with a greater than or equal to fourfold increase developed RSV-MAALRI. Rates of RSV-MAARI and RSV-MAALRI in placebo recipients were 21% and 7%, respectively. Given these rates, a study of 540 RSV-naive children would have 90% power to demonstrate ≥55% efficacy against RSV-MAARI and ≥80% efficacy against RSV-MAALRI; if rates were 10% and 3%, a study of 1,300 RSV-naive children would be needed.Conclusions: Rapid development of a live-attenuated RSV vaccine could contribute substantially to reducing the global burden of RSV disease.


Assuntos
Infecções por Vírus Respiratório Sincicial/prevenção & controle , Vacinas contra Vírus Sincicial Respiratório/uso terapêutico , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Ensaios Clínicos Fase I como Assunto , Feminino , Humanos , Imunogenicidade da Vacina/imunologia , Memória Imunológica/imunologia , Lactente , Masculino , Ensaios Clínicos Controlados Aleatórios como Assunto , Infecções por Vírus Respiratório Sincicial/fisiopatologia , Vírus Sincicial Respiratório Humano/imunologia , Resultado do Tratamento , Vacinas Atenuadas/uso terapêutico
5.
J Infect Dis ; 224(11): 1916-1924, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34009371

RESUMO

BACKGROUND: Perinatal human immunodeficiency virus type 1 (HIV-1) continues to occur due to barriers to effective antiretroviral prevention that might be mitigated by long-acting broadly neutralizing monoclonal antibodies (bNAbs). METHODS: An extended half-life bNAb, VRC01LS, was administered subcutaneously at 80 mg/dose after birth to HIV-1-exposed, nonbreastfed (cohort 1, n = 10) and breastfed (cohort 2, n = 11) infants. Cohort 2 received a second dose (100 mg) at 12 weeks. All received antiretroviral prophylaxis. VRC01LS levels were compared to VRC01 levels determined in a prior cohort. RESULTS: Local reactions (all grade ≤2) occurred in 67% and 20% after dose 1 and dose 2, respectively. The weight-banded dose (mean 28.8 mg/kg) of VRC01LS administered subcutaneously achieved a mean (standard deviation) plasma level of 222.3 (71.6) µg/mL by 24 hours and 44.0 (11.6) µg/mL at week 12, prior to dose 2. The preestablished target of ≥50 µg/mL was attained in 95% and 32% at weeks 8 and 12, respectively. The terminal half-life was 37-41 days. VRC01LS level after 1 dose was significantly greater (P <.002) than after a VRC01 dose (20 mg/kg). No infants acquired HIV-1. CONCLUSIONS: VRC01LS was well tolerated with pharmacokinetics that support further studies of more potent long-acting bNAbs as adjunct treatment with antiretrovirals to prevent infant HIV-1 transmission.


Assuntos
Antirretrovirais/administração & dosagem , Anticorpos Monoclonais/farmacocinética , Anticorpos Amplamente Neutralizantes/farmacologia , Anticorpos Anti-HIV , Infecções por HIV/prevenção & controle , HIV-1/efeitos dos fármacos , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Antirretrovirais/uso terapêutico , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/efeitos adversos , Anticorpos Amplamente Neutralizantes/administração & dosagem , Relação Dose-Resposta a Droga , Feminino , Anticorpos Anti-HIV/administração & dosagem , Anticorpos Anti-HIV/efeitos adversos , Infecções por HIV/sangue , Infecções por HIV/tratamento farmacológico , HIV-1/imunologia , HIV-1/patogenicidade , Meia-Vida , Humanos , Recém-Nascido , Masculino
6.
J Neurovirol ; 27(5): 702-715, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34524627

RESUMO

We investigated the association of metabolic syndrome (MetS) and its components [abdominal obesity, elevated triglycerides (TG), low HDL cholesterol, elevated blood pressure (BP), and impaired fasting glycemia (IFG)] with neurocognitive impairment in youth with perinatally acquired HIV (YPHIV) or who are perinatally HIV-exposed uninfected (YPHEU). This was an observational study with a comparison group of 350 YPHIV and 68 YPHEU ages 10-19 years. Youth with MetS components measured between 1 year before and 3 months after a baseline neurocognitive assessment (Wechsler Intelligence Scale) were selected from the Pediatric HIV/AIDS Cohort Study (PHACS). A sub-group completed another assessment 3 years later. We assessed the association of each baseline MetS component with five standardized neurocognitive indices at baseline and changes in indices over time. At baseline, 15% of YPHIV and 18% of YPHEU met criteria for ≥ 2 MetS components. Among YPHIV, there was no association between MetS components and neurocognitive indices at baseline; however, over time, elevated baseline BP was associated with a greater decrease in mean Perceptual Reasoning scores (-4.3;95%CI: -8.8,0.3) and ≥ 2 MetS components with a greater decrease in mean Processing Speed scores (-5.1;95%CI: -9.4, -0.8). Among YPHEU, elevated TG was associated with lower mean Verbal Comprehension, Perceptual Reasoning, and Full-scale IQ scores at baseline, and IFG with lower mean Verbal Comprehension scores. Components of MetS in YPHIV (elevated BP) and YPHEU (elevated TG and IFG) were associated with lower neurocognitive performance index scores. Studies to elucidate how modifying metabolic risk factors early in life may improve neurocognitive outcomes in this population are warranted.


Assuntos
Infecções por HIV , Síndrome Metabólica , Adolescente , Adulto , Criança , Estudos de Coortes , Infecções por HIV/psicologia , Humanos , Obesidade/complicações , Fatores de Risco , Adulto Jovem
7.
J Infect Dis ; 221(12): 2050-2059, 2020 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-32006006

RESUMO

BACKGROUND: Respiratory syncytial virus (RSV) is the leading viral cause of severe pediatric respiratory illness, and vaccines are needed. Live RSV vaccine D46/NS2/N/ΔM2-2-HindIII, attenuated by deletion of the RSV RNA regulatory protein M2-2, is based on previous candidate LID/ΔM2-2 but incorporates prominent differences from MEDI/ΔM2-2, which was more restricted in replication in phase 1. METHODS: RSV-seronegative children aged 6-24 months received 1 intranasal dose (105 plaque-forming units [PFUs] of D46/NS2/N/ΔM2-2-HindIII [n = 21] or placebo [n = 11]) and were monitored for vaccine shedding, reactogenicity, RSV-antibody responses and RSV-associated medically attended acute respiratory illness (RSV-MAARI) and antibody responses during the following RSV season. RESULTS: All 21 vaccinees were infected with vaccine; 20 (95%) shed vaccine (median peak titer, 3.5 log10 PFUs/mL with immunoplaque assay and 6.1 log10 copies/mL with polymerase chain reaction). Serum RSV-neutralizing antibodies and anti-RSV fusion immunoglobulin G increased ≥4-fold in 95% and 100% of vaccines, respectively. Mild upper respiratory tract symptoms and/or fever occurred in vaccinees (76%) and placebo recipients (18%). Over the RSV season, RSV-MAARI occurred in 2 vaccinees and 4 placebo recipients. Three vaccinees had ≥4-fold increases in serum RSV-neutralizing antibody titers after the RSV season without RSV-MAARI. CONCLUSIONS: D46/NS2/N/ΔM2-2-HindIII had excellent infectivity and immunogenicity and primed vaccine recipients for anamnestic responses, encouraging further evaluation of this attenuation strategy. CLINICAL TRIALS REGISTRATION: NCT03102034 and NCT03099291.


Assuntos
Anticorpos Antivirais/sangue , Infecções por Vírus Respiratório Sincicial/prevenção & controle , Vacinas contra Vírus Sincicial Respiratório/imunologia , Vírus Sincicial Respiratório Humano/imunologia , Proteínas Virais/genética , Adolescente , Anticorpos Neutralizantes/sangue , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Criança , Deleção de Genes , Humanos , Interações Hidrofóbicas e Hidrofílicas , Pequeno RNA não Traduzido/química , Pequeno RNA não Traduzido/genética , Pequeno RNA não Traduzido/imunologia , RNA Viral/química , RNA Viral/genética , RNA Viral/imunologia , Infecções por Vírus Respiratório Sincicial/imunologia , Infecções por Vírus Respiratório Sincicial/virologia , Vacinas contra Vírus Sincicial Respiratório/administração & dosagem , Vacinas contra Vírus Sincicial Respiratório/química , Vacinas contra Vírus Sincicial Respiratório/genética , Vírus Sincicial Respiratório Humano/genética , Vacinas Atenuadas/administração & dosagem , Vacinas Atenuadas/química , Vacinas Atenuadas/genética , Vacinas Atenuadas/imunologia
8.
J Infect Dis ; 221(4): 534-543, 2020 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-31758177

RESUMO

BACKGROUND: The safety and immunogenicity of live respiratory syncytial virus (RSV) candidate vaccine, LID/ΔM2-2/1030s, with deletion of RSV ribonucleic acid synthesis regulatory protein M2-2 and genetically stabilized temperature-sensitivity mutation 1030s in the RSV polymerase protein was evaluated in RSV-seronegative children. METHODS: Respiratory syncytial virus-seronegative children ages 6-24 months received 1 intranasal dose of 105 plaque-forming units (PFU) of LID/ΔM2-2/1030s (n = 21) or placebo (n = 11). The RSV serum antibodies, vaccine shedding, and reactogenicity were assessed. During the following RSV season, medically attended acute respiratory illness (MAARI) and pre- and postsurveillance serum antibody titers were monitored. RESULTS: Eighty-five percent of vaccinees shed LID/ΔM2-2/1030s vaccine (median peak nasal wash titers: 3.1 log10 PFU/mL by immunoplaque assay; 5.1 log10 copies/mL by reverse-transcription quantitative polymerase chain reaction) and had ≥4-fold rise in serum-neutralizing antibodies. Respiratory symptoms and fever were common (60% vaccinees and 27% placebo recipients). One vaccinee had grade 2 wheezing with rhinovirus but without concurrent LID/ΔM2-2/1030s shedding. Five of 19 vaccinees had ≥4-fold increases in antibody titers postsurveillance without RSV-MAARI, indicating anamnestic responses without significant illness after infection with community-acquired RSV. CONCLUSIONS: LID/ΔM2-2/1030s had excellent infectivity without evidence of genetic instability, induced durable immunity, and primed for anamnestic antibody responses, making it an attractive candidate for further evaluation.


Assuntos
Deleção de Genes , RNA Polimerase Dependente de RNA/genética , Infecções por Vírus Respiratório Sincicial/prevenção & controle , Vacinas contra Vírus Sincicial Respiratório/imunologia , Vírus Sincicial Respiratório Humano/imunologia , Vacinação , Proteínas Virais/genética , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Temperatura Corporal , Método Duplo-Cego , Feminino , Humanos , Imunogenicidade da Vacina , Lactente , Masculino , Mutação Puntual , Infecções por Vírus Respiratório Sincicial/imunologia , Infecções por Vírus Respiratório Sincicial/virologia , Vacinas contra Vírus Sincicial Respiratório/efeitos adversos , Vírus Sincicial Respiratório Humano/genética , Vacinas Atenuadas , Replicação Viral/genética
9.
J Infect Dis ; 222(4): 628-636, 2020 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-31681963

RESUMO

BACKGROUND: Although mother-to-child human immunodeficiency virus (HIV) transmission has dramatically decreased with maternal antiretroviral therapy, breast milk transmission accounts for most of the 180 000 new infant HIV infections annually. Broadly neutralizing antibodies (bNAb) may further reduce transmission. METHODS: A Phase 1 safety and pharmacokinetic study was conducted: a single subcutaneous (SC) dose of 20 or 40 mg/kg (Dose Groups 1 and 2, respectively) of the bNAb VRC01 was administered to HIV-exposed infants soon after birth. Breastfeeding infants (Dose Group 3) received 40 mg/kg SC VRC01 after birth and then 20 mg/kg/dose SC monthly. All infants received appropriate antiretroviral prophylaxis. RESULTS: Forty infants were enrolled (21 in the United States, 19 in Africa). Subcutaneous VRC01 was safe and well tolerated with only mild-to-moderate local reactions, primarily erythema, which rapidly resolved. For multiple-dose infants, local reactions decreased with subsequent injections. VRC01 was rapidly absorbed after administration, with peak concentrations 1-6 days postdose. The 40 mg/kg dose resulted in 13 of 14 infants achieving the serum 50 micrograms (mcg)/mL target at day 28. Dose Group 3 infants maintained concentrations greater than 50 mcg/mL throughout breastfeeding. CONCLUSIONS: Subcutaneous VRC01 as single or multiple doses is safe and well tolerated in very young infants and is suitable for further study to prevent HIV transmission in infants.


Assuntos
Anticorpos Monoclonais/administração & dosagem , Anticorpos Amplamente Neutralizantes/administração & dosagem , Anticorpos Anti-HIV/administração & dosagem , Infecções por HIV/tratamento farmacológico , HIV-1/efeitos dos fármacos , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , África , Anticorpos Monoclonais/efeitos adversos , Anticorpos Monoclonais/farmacocinética , Anticorpos Amplamente Neutralizantes/efeitos adversos , Feminino , Anticorpos Anti-HIV/efeitos adversos , Infecções por HIV/sangue , Humanos , Recém-Nascido , Injeções Subcutâneas , Modelos Lineares , Masculino , Estados Unidos
11.
J Virol ; 92(1)2018 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-29021402

RESUMO

In the RV144 vaccine trial, IgG responses against the HIV envelope variable loops 1 and 2 (V1V2) were associated with decreased HIV acquisition risk. We previously reported that infants immunized with an MF59-adjuvanted rgp120 vaccine developed higher-magnitude anti-V1V2 IgG responses than adult RV144 vaccinees. To determine whether the robust antibody response in infants is due to differences in vaccine regimens or to inherent differences between the adult and infant immune systems, we compared Env-specific IgG responses in adults and infants immunized with the same MF59- and alum-adjuvanted HIV envelope vaccines. At peak immunogenicity, the magnitudes of the gp120- and V1V2-specific IgG responses were comparable between adults and infants immunized with the alum/MNrgp120 vaccine (gp120 median fluorescence intensities [FIs] in infants = 7,118 and in adults = 11,510, P = 0.070; V1V2 median MFIs of 512 [infants] and 804 [adults], P = 0.50), whereas infants immunized with the MF59/SF-2 rgp120 vaccine had higher-magnitude antibody levels than adults (gp120 median FIs of 15,509 [infants] and 2,290 [adults], P < 0.001; V1V2 median FIs of 23,926 [infants] and 1,538 [adults]; P < 0.001). Six months after peak immunogenicity, infants maintained higher levels Env-specific IgG than adults. Anti-V1V2 IgG3 antibodies that were associated with decreased HIV-1 risk in RV144 vaccinees were present in 43% of MF59/rgp120-vaccinated infants but only in 12% of the vaccinated adults (P = 0.0018). Finally, in contrast to the rare vaccine-elicited Env-specific IgA in infants, rgp120 vaccine-elicited Env-specific IgA was frequently detected in adults. Our results suggest that vaccine adjuvants differently modulate gp120-specific antibody responses in adults and infants and that infants can robustly respond to HIV Env immunization.IMPORTANCE More than 150,000 pediatric HIV infections occur yearly, despite the availability of antiretroviral prophylaxis. A pediatric HIV vaccine could reduce the number of these ongoing infant infections and also prime for long-term immunity prior to sexual debut. We previously reported that immunization of infants with an MF59-adjuvanted recombinant gp120 vaccine induced higher-magnitude, potentially protective anti-V1V2 IgG responses than in adult vaccinees receiving the moderately effective RV144 vaccine. In the present study, we demonstrate that the robust response observed in infants is not due to differences in vaccine regimen or vaccine dose between adults and infants. Our results suggest that HIV vaccine adjuvants may differentially modulate immune responses in adults and infants, highlighting the need to conduct vaccine trials in pediatric populations.


Assuntos
Vacinas contra a AIDS/imunologia , Anticorpos Anti-HIV/sangue , Proteína gp120 do Envelope de HIV/imunologia , Imunogenicidade da Vacina , Imunoglobulina G/sangue , Esqualeno/imunologia , Produtos do Gene env do Vírus da Imunodeficiência Humana/imunologia , Vacinas contra a AIDS/administração & dosagem , Adjuvantes Imunológicos , Adulto , Fatores Etários , Anticorpos Anti-HIV/imunologia , Proteína gp120 do Envelope de HIV/administração & dosagem , Infecções por HIV/imunologia , Infecções por HIV/prevenção & controle , Humanos , Imunoglobulina A/sangue , Imunoglobulina A/imunologia , Lactente , Polissorbatos/administração & dosagem , Esqualeno/administração & dosagem , Vacinação
12.
J Infect Dis ; 217(9): 1338-1346, 2018 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-29509929

RESUMO

Background: Respiratory syncytial virus (RSV) is the most important viral cause of severe respiratory illness in young children and lacks a vaccine. RSV cold-passage/stabilized 2 (RSVcps2) is a modification of a previously evaluated vaccine candidate in which 2 major attenuating mutations have been stabilized against deattenuation. Methods: RSV-seronegative 6-24-month-old children received an intranasal dose of 105.3 plaque-forming units (PFU) of RSVcps2 (n = 34) or placebo (n = 16) (International Maternal Pediatric Adolescent AIDS Clinical Trials protocol P1114 and companion protocol CIR285). RSV serum neutralizing antibody titers before and 56 days after vaccination, vaccine virus infectivity (defined as vaccine virus shedding detectable in nasal wash and/or a ≥4-fold rise in serum antibodies), reactogenicity, and genetic stability were assessed. During the following RSV transmission season, participants were monitored for respiratory illness, with serum antibody titers measured before and after the season. Results: A total of 85% of vaccinees were infected with RSVcps2 (median peak titer, 0.5 log10 PFU/mL by culture and 2.9 log10 copies/mL by polymerase chain reaction analysis); 77% shed vaccine virus, and 59% developed a ≥4-fold rise in RSV-serum neutralizing antibody titers. Respiratory tract and/or febrile illness occurred at the same rate (50%) in the vaccine and placebo groups. Deattenuation was not detected at either of 2 stabilized mutation sites. Conclusions: RSVcps2 was well tolerated and moderately immunogenic and had increased genetic stability in 6-24-month-old RSV-seronegative children. Clinical Trials Registration: NCT01852266 and NCT01968083.


Assuntos
Anticorpos Antivirais/sangue , Infecções por Vírus Respiratório Sincicial/prevenção & controle , Vacinas contra Vírus Sincicial Respiratório/imunologia , Vírus Sincicial Respiratório Humano/genética , Anticorpos Neutralizantes , Feminino , Humanos , Imunogenicidade da Vacina , Lactente , Masculino , Mutação , Vacinas Atenuadas/imunologia , Replicação Viral
13.
J Infect Dis ; 217(9): 1347-1355, 2018 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-29509911

RESUMO

Background: Live respiratory syncytial virus (RSV) candidate vaccine LIDΔM2-2 is attenuated by deletion of the RSV RNA regulatory protein M2-2, resulting in upregulated viral gene transcription and antigen expression but reduced RNA replication. Methods: RSV-seronegative children ages 6-24 months received a single intranasal dose of 105 plaque forming units (PFU) of LIDΔM2-2 (n = 20) or placebo (n = 9) (NCT02237209, NCT02040831). RSV serum antibodies, vaccine infectivity, and reactogenicity were assessed. During the following RSV season, participants were monitored for respiratory illness and pre- and post-RSV season serum antibodies. Results: Vaccine virus was shed by 95% of vaccinees (median peak titers of 3.8 log10 PFU/mL by quantitative culture and 6.3 log10 copies/mL by PCR); 90% had ≥4-fold rise in serum neutralizing antibodies. Respiratory symptoms and fever were common in vaccine (95%) and placebo (78%). One vaccinee had grade 2 rhonchi concurrent with vaccine shedding, rhinovirus, and enterovirus. Eight of 19 vaccinees versus 2 of 9 placebo recipients had substantially increased RSV antibody titers after the RSV season without medically attended RSV disease, indicating anamnestic vaccine responses to wild-type RSV without significant illness. Conclusion: LIDΔM2-2 had excellent infectivity and immunogenicity, encouraging further study of vaccine candidates attenuated by M2-2 deletion. Clinical Trials Registration: NCT02237209, NCT02040831.


Assuntos
Anticorpos Neutralizantes/sangue , Infecções por Vírus Respiratório Sincicial/prevenção & controle , Vacinas contra Vírus Sincicial Respiratório/imunologia , Vírus Sincicial Respiratório Humano/genética , Proteínas Virais/genética , Anticorpos Antivirais/sangue , Método Duplo-Cego , Feminino , Humanos , Lactente , Masculino , Vacinas Atenuadas/imunologia , Replicação Viral
14.
J Infect Dis ; 215(3): 368-377, 2017 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-27932619

RESUMO

Background: Among infants exposed to human immunodeficiency virus (HIV) type 1, mixed breastfeeding is associated with higher postnatal HIV-1 transmission than exclusive breastfeeding, but the mechanisms of this differential risk are uncertain. Methods: HIV-1-exposed Ugandan infants were prospectively assessed during the first year of life for feeding practices and T-cell maturation, intestinal homing (ß7hi), activation, and HIV-1 coreceptor (CCR5) expression in peripheral blood. Infants receiving only breast milk and those with introduction of other foods before 6 months were categorized as exclusive and nonexclusive, respectively. Results: Among CD4+ and CD8+ T cells, the expression of memory, activation, and CCR5 markers increased rapidly from birth to week 2, peaking at week 6, whereas cells expressing the intestinal homing marker increased steadily in the central memory (CM) and effector memory T cells over 48 weeks. At 24 weeks, when feeding practices had diverged, nonexclusively breastfed infants showed increased frequencies and absolute counts of ß7hi CM CD4+ and CD8+ T cells, including the HIV-1-targeted cells with CD4+ß7hi/CCR5+ coexpression, as well as increased activation. Conclusions: The T-cell phenotype associated with susceptibility to HIV-1 infection (CCR5+, gut-homing, CM CD4+ T cells) was preferentially expressed in nonexclusively breastfed infants, a group of infants at increased risk for HIV-1 acquisition.


Assuntos
Aleitamento Materno/efeitos adversos , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD4-Positivos/virologia , Infecções por HIV/imunologia , HIV-1/fisiologia , Adolescente , Adulto , Linfócitos T CD4-Positivos/imunologia , Movimento Celular , Suscetibilidade a Doenças , Feminino , Infecções por HIV/transmissão , Humanos , Memória Imunológica , Lactente , Recém-Nascido , Intestinos/imunologia , Ativação Linfocitária , Linfopoese , Mães , Fenótipo , Estudos Prospectivos , Receptores CCR5/biossíntese , Uganda , Adulto Jovem
15.
Clin Trials ; 14(3): 314-318, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28135804

RESUMO

INTRODUCTION: Equipoise is usually discussed as an ethical issue in clinical trials. However, it also has practical implications. BACKGROUND: Clinical equipoise is usually construed to mean uncertainty or disagreement among the expert clinician community. However, an individual physician's sense of equipoise may vary by location, based on the local standard of care or availability of specific treatment options, and these differences can affect providers' willingness to enroll participants into clinical trials. There are also logistical barriers to enrollment in international trials due to prolonged timelines for approvals by government agencies and ethical review boards. CASE STUDY: A multinational clinical trial of bridging strategies for treatment of non-adherent HIV-infected youth, experienced differing perceptions of equipoise due to disparities in availability of treatment options by country. Unfortunately, the countries with most demand for the trial were those where the approval process was most delayed, and the study was closed early due to slow accrual. DISCUSSION: When planning multicenter clinical trials, it is important to take into account heterogeneity among research sites and try to anticipate differences in equipoise and logistical factors between sites, in order to plan to address these issues at the design stage.


Assuntos
Pesquisa Biomédica/métodos , Ensaios Clínicos como Assunto , Infecções por HIV/terapia , Seleção de Pacientes , Projetos de Pesquisa , Equipolência Terapêutica , Saúde Global , Disparidades em Assistência à Saúde , Humanos , Estudos Multicêntricos como Assunto , Cooperação e Adesão ao Tratamento , Incerteza
16.
Cancer ; 122(17): 2633-45, 2016 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-27258162

RESUMO

Persons with a family history (FH) of colorectal cancer (CRC) or adenomas that are not due to known hereditary syndromes have an increased risk for CRC. An understanding of these risks, screening recommendations, and screening behaviors can inform strategies for reducing the CRC burden in these families. A comprehensive review of the literature published within the past 10 years has been performed to assess what is known about cancer risk, screening guidelines, adherence and barriers to screening, and effective interventions in persons with an FH of CRC and to identify FH tools used to identify these individuals and inform care. Existing data show that having 1 affected first-degree relative (FDR) increases the CRC risk 2-fold, and the risk increases with multiple affected FDRs and a younger age at diagnosis. There is variability in screening recommendations across consensus guidelines. Screening adherence is <50% and is lower in persons under the age of 50 years. A provider's recommendation, multiple affected relatives, and family encouragement facilitate screening; insufficient collection of FH, low knowledge of guidelines, and poor family communication are important barriers. Effective interventions incorporate strategies for overcoming barriers, but these have not been broadly tested in clinical settings. Four strategies for reducing CRC in persons with familial risk are suggested: 1) improving the collection and utilization of the FH of cancer, 2) establishing a consensus for screening guidelines by FH, 3) enhancing provider-patient knowledge of guidelines and communication about CRC risk, and 4) encouraging survivors to promote screening within their families and partnering with existing screening programs to expand their reach to high-risk groups. Cancer 2016. © 2016 American Cancer Society. Cancer 2016;122:2633-2645. © 2016 American Cancer Society.


Assuntos
Neoplasias Colorretais/epidemiologia , Neoplasias Colorretais/genética , Detecção Precoce de Câncer , Predisposição Genética para Doença , Neoplasias Colorretais/diagnóstico , Humanos , Medição de Risco
17.
Infect Dis Obstet Gynecol ; 2016: 9848041, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27127401

RESUMO

Combination antiretroviral therapy (cART) is successfully used for prevention of perinatal HIV transmission. To investigate safety, we compared adverse events (AE) among infants exposed to different maternal cART regimens. We reviewed 158 HIV-uninfected infants born between 1997 and 2009, using logistic regression to model grade ≥1 AE and grade ≥3 AE as a function of maternal cART and confounding variables (preterm, C-section, illicit drug use, race, ethnicity, infant antiretrovirals, and maternal viremia). Frequently used cART regimens included zidovudine (63%), lamivudine (80%), ritonavir-boosted lopinavir (37%), nelfinavir (26%), and atazanavir (10%). At birth, anemia occurred in 13/140 infants (9%), neutropenia in 27/107 (25%), thrombocytopenia in 5/133 (4%), and liver enzyme elevation in 21/130 (16%). Corresponding rates of AE at 4 weeks were 59/141 (42%), 54/130 (42%), 3/137 (2%), and 3/104 (3%), respectively. Serious AE (grade ≥ 3) exceeded 2% only for neutropenia (13% at birth; 9% at 4 weeks). Compared with infants exposed to maternal lopinavir/ritonavir, infants exposed to nelfinavir and atazanavir had a 5-fold and 4-fold higher incidence of AE at birth, respectively. In conclusion, hematologic and hepatic AE were frequent, but rarely serious. In this predominantly protease inhibitor-treated population, lopinavir/ritonavir was associated with the lowest rate of infant AE.


Assuntos
Sulfato de Atazanavir/efeitos adversos , Inibidores da Protease de HIV/uso terapêutico , Doenças do Recém-Nascido/induzido quimicamente , Lopinavir/efeitos adversos , Nelfinavir/efeitos adversos , Complicações Infecciosas na Gravidez/tratamento farmacológico , Ritonavir/efeitos adversos , Quimioterapia Combinada , Feminino , Inibidores da Protease de HIV/administração & dosagem , Humanos , Recém-Nascido , Masculino , Gravidez , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Estudos Retrospectivos
18.
J Infect Dis ; 211(4): 508-17, 2015 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-25170104

RESUMO

BACKGROUND: Infant responses to vaccines can be impeded by maternal antibodies and immune system immaturity. It is therefore unclear whether human immunodeficiency virus type 1 (HIV-1) vaccination would elicit similar responses in adults and infants. METHOD: HIV-1 Env-specific antibody responses were evaluated in 2 completed pediatric vaccine trials. In the Pediatric AIDS Clinical Trials Group (PACTG) 230 protocol, infants were vaccinated with 4 doses of Chiron rgp120 with MF59 (n=48), VaxGen rgp120 with aluminum hydroxide (alum; n=49), or placebo (n=19) between 0 and 20 weeks of age. In PACTG 326, infants received 4 doses of ALVAC-HIV-1/AIDSVAX B/B with alum (n=9) or placebo (n=13) between 0 and 12 weeks of age. RESULTS: By 52 weeks of age, the majority of maternally acquired antibodies had waned and vaccine Env-specific immunoglobulin G (IgG) responses in vaccinees were higher than in placebo recipients. Chiron vaccine recipients had higher and more-durable IgG responses than VaxGen vaccine recipients or ALVAC/AIDSVAX vaccinees, with vaccine-elicited IgG responses still detectable in 56% of recipients at 2 years of age. Remarkably, at peak immunogenicity, the concentration of anti-V1V2 IgG, a response associated with a reduced risk of HIV-1 acquisition in the RV144 adult vaccine trial, was 22-fold higher in Chiron vaccine recipients, compared with RV144 vaccinees. CONCLUSION: As exemplified by the Chiron vaccine regimen, vaccination of infants against HIV-1 can induce robust, durable Env-specific IgG responses, including anti-V1V2 IgG.


Assuntos
Vacinas contra a AIDS/imunologia , Anticorpos Anti-HIV/imunologia , Proteína gp120 do Envelope de HIV/imunologia , HIV-1/imunologia , Imunoglobulina A/imunologia , Imunoglobulina G/imunologia , Vacinas contra a AIDS/administração & dosagem , Anticorpos Anti-HIV/sangue , Infecções por HIV/prevenção & controle , Humanos , Imunoglobulina A/sangue , Imunoglobulina G/sangue , Lactente , Recém-Nascido , Estudos Retrospectivos
19.
PLoS Med ; 11(4): e1001616, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24714363

RESUMO

Yegor Voronin and colleagues explore how monoclonal antibodies against HIV could provide a new opportunity to further reduce mother-to-child transmission of HIV and propose that new interventions should consider issues related to implementation, feasibility, and access. Please see later in the article for the Editors' Summary.


Assuntos
Anticorpos Monoclonais/sangue , Anticorpos Anti-HIV/sangue , Infecções por HIV/prevenção & controle , Infecções por HIV/transmissão , HIV/imunologia , Adulto , Criança , Feminino , Infecções por HIV/virologia , Humanos , Lactente , Recém-Nascido , Masculino , Mães
20.
Ann Intern Med ; 157(9): 611-20, 2012 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-23128861

RESUMO

BACKGROUND: Persons with a negative result on screening colonoscopy are recommended to repeat the procedure in 10 years. OBJECTIVE: To assess the effectiveness and costs of colonoscopy versus other rescreening strategies after an initial negative colonoscopy result. DESIGN: Microsimulation model. DATA SOURCES: Literature and data from the Surveillance, Epidemiology, and End Results program. TARGET POPULATION: Persons aged 50 years who had no adenomas or cancer detected on screening colonoscopy. TIME HORIZON: Lifetime. PERSPECTIVE: Societal. INTERVENTION: No further screening or rescreening starting at age 60 years with colonoscopy every 10 years, annual highly sensitive guaiac fecal occult blood testing (HSFOBT), annual fecal immunochemical testing (FIT), or computed tomographic colonography (CTC) every 5 years. OUTCOME MEASURES: Lifetime cases of colorectal cancer, life expectancy, and lifetime costs per 1000 persons, assuming either perfect or imperfect adherence. RESULTS OF BASE-CASE ANALYSIS: Rescreening with any method substantially reduced the risk for colorectal cancer compared with no further screening (range, 7.7 to 12.6 lifetime cases per 1000 persons [perfect adherence] and 17.7 to 20.9 lifetime cases per 1000 persons [imperfect adherence] vs. 31.3 lifetime cases per 1000 persons with no further screening). In both adherence scenarios, the differences in life-years across rescreening strategies were small (range, 30 893 to 30 902 life-years per 1000 persons [perfect adherence] vs. 30 865 to 30 869 life-years per 1000 persons [imperfect adherence]). Rescreening with HSFOBT, FIT, or CTC had fewer complications and was less costly than continuing colonoscopy. RESULTS OF SENSITIVITY ANALYSIS: Results were sensitive to test-specific adherence rates. LIMITATION: Data on adherence to rescreening were limited. CONCLUSION: Compared with the currently recommended strategy of continuing colonoscopy every 10 years after an initial negative examination, rescreening at age 60 years with annual HSFOBT, annual FIT, or CTC every 5 years provides approximately the same benefit in life-years with fewer complications at a lower cost. Therefore, it is reasonable to use other methods to rescreen persons with negative colonoscopy results. PRIMARY FUNDING SOURCE: National Cancer Institute.


Assuntos
Colonoscopia/economia , Neoplasias Colorretais/prevenção & controle , Detecção Precoce de Câncer/economia , Detecção Precoce de Câncer/métodos , Programas de Rastreamento/economia , Programas de Rastreamento/métodos , Adenoma/prevenção & controle , Colonografia Tomográfica Computadorizada/efeitos adversos , Colonografia Tomográfica Computadorizada/economia , Colonoscopia/efeitos adversos , Simulação por Computador , Detecção Precoce de Câncer/efeitos adversos , Fezes , Custos de Cuidados de Saúde , Humanos , Testes Imunológicos/economia , Programas de Rastreamento/efeitos adversos , Pessoa de Meia-Idade , Sangue Oculto , Cooperação do Paciente , Sensibilidade e Especificidade , Fatores de Tempo
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