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1.
J Infect Dis ; 229(6): 1796-1802, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38206187

RESUMO

BACKGROUND: Limited data are available regarding the susceptibility of the reverse transcriptase V106 polymorphism to doravirine. METHODS: Doravirine susceptibility was measured in site-directed mutants (SDMs) containing V106I, V106A, V106M, and Y188L mutations in subtype B (NL4-3, HXB2) and CRF02_AG background and in recombinant viruses with RT harboring V106I alone derived from 50 people with HIV. RESULTS: HIV-1 B subtype was detected in 1523 of 2705 cases. Prevalence of V106I was 3.2% in B and 2.5% in non-B subtypes, and was higher in subtype F (8.1%) and D (14.3%). Fold-changes (FC) in susceptibility for SDMs were below doravirine biological cutoff (3.0) for V106I, but not for V106A, V106M, and Y188L. Clinically derived viruses tested included 22 B (median FC, 1.2; interquartile range [IQR], 0.9-1.6) and 28 non-B subtypes (median FC, 1.8; IQR, 0.9-3.0). Nine (18%) viruses showed FC values equal or higher than the doravirine biological FC cutoff. CONCLUSIONS: The prevalence of the HIV-1 RT V106I polymorphism in MeditRes HIV consortium remains low, but significantly more prevalent in subtypes D and F. V106I minimally decreased the susceptibility to doravirine in SDMs and most clinical isolates. Reduced susceptibility seems to occur at increased frequency in subtype F1; however, the clinical impact remains to be investigated. CLINICAL TRIALS REGISTRATION: NCT04894357.


Assuntos
Fármacos Anti-HIV , Farmacorresistência Viral , Infecções por HIV , Transcriptase Reversa do HIV , HIV-1 , Piridonas , Triazóis , Humanos , HIV-1/genética , HIV-1/efeitos dos fármacos , HIV-1/classificação , HIV-1/enzimologia , Transcriptase Reversa do HIV/genética , Infecções por HIV/virologia , Infecções por HIV/epidemiologia , Piridonas/farmacologia , Farmacorresistência Viral/genética , Fármacos Anti-HIV/farmacologia , Triazóis/farmacologia , Polimorfismo Genético , Prevalência , Masculino , Feminino , Inibidores da Transcriptase Reversa/farmacologia , Adulto , Genótipo , Fenótipo , Pessoa de Meia-Idade
2.
Small ; 20(19): e2307045, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38100142

RESUMO

Since WHO has declared the COVID-19 outbreak a global pandemic, nearly seven million deaths have been reported. This efficient spread of Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) is facilitated by the ability of the spike glycoprotein to bind multiple cell membrane receptors. Although ACE2 is identified as the main receptor for SARS-CoV-2, other receptors could play a role in viral entry. Among others, C-type lectins such as DC-SIGN are identified as efficient trans-receptor for SARS-CoV-2 infection, so the use of glycomimetics to inhibit the infection through the DC-SIGN blockade is an encouraging approach. In this regard, multivalent nanostructures based on glycosylated [60]fullerenes linked to a central porphyrin scaffold have been designed and tested against DC-SIGN-mediated SARS-CoV-2 infection. First results show an outstanding inhibition of the trans-infection up to 90%. In addition, a deeper understanding of nanostructure-receptor binding is achieved through microscopy techniques, high-resolution NMR experiments, Quartz Crystal Microbalance experiments, and molecular dynamic simulations.


Assuntos
Moléculas de Adesão Celular , Fulerenos , Lectinas Tipo C , Porfirinas , Receptores de Superfície Celular , SARS-CoV-2 , Humanos , Moléculas de Adesão Celular/metabolismo , Moléculas de Adesão Celular/antagonistas & inibidores , COVID-19/virologia , Tratamento Farmacológico da COVID-19 , Fulerenos/química , Fulerenos/farmacologia , Lectinas Tipo C/metabolismo , Lectinas Tipo C/antagonistas & inibidores , Simulação de Dinâmica Molecular , Porfirinas/química , Porfirinas/farmacologia , Ligação Proteica , Receptores de Superfície Celular/metabolismo , Receptores de Superfície Celular/antagonistas & inibidores , SARS-CoV-2/efeitos dos fármacos , SARS-CoV-2/metabolismo , Glicoproteína da Espícula de Coronavírus/metabolismo , Glicoproteína da Espícula de Coronavírus/química
3.
J Neurosci Res ; 102(6): e25362, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38895852

RESUMO

Sudden infant death syndrome (SIDS)-the sudden and unexplained death of a seemingly healthy infant, <1 year old-may be associated with abnormalities in the brain regions that underlie breathing and arousal during sleep. While post-mortem studies suggest abnormalities in SIDS infants' brainstems, there are no studies of these infants' brainstem function before death. One way to assess the function of the brainstem is with auditory brainstem response (ABR), a routine hearing-screening method that noninvasively measures the brainstem's response to sound. We hypothesize that anomalies in newborns' ABR measures may predict SIDS. Indeed, previous studies identified abnormalities in ABR characteristics in small samples of near-miss SIDS infants hospitalized for infant apnea syndrome. However, there is a need to examine the ABRs of infants who died of SIDS. Therefore, in the current study, we propose integrating two secondary datasets to examine newborns' ABRs (N = 156,972), including those who later died of SIDS (n = ~42; .27 out of every 1000 infants), using existing archived records of neonatal ABR results from a sample of newborns born in Florida. We hypothesize that infants who die from SIDS are more likely than non-SIDS infants to have abnormal ABRs as newborns. Understanding the association between SIDS and ABR may facilitate more accurate identification of an infant's risk for SIDS at birth, enabling increased monitoring, which may facilitate interventions and improve survivorship.


Assuntos
Potenciais Evocados Auditivos do Tronco Encefálico , Morte Súbita do Lactente , Humanos , Potenciais Evocados Auditivos do Tronco Encefálico/fisiologia , Recém-Nascido , Masculino , Feminino , Tronco Encefálico/fisiopatologia , Lactente
4.
PLoS Pathog ; 18(1): e1009784, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-35081156

RESUMO

African swine fever virus (ASFV) infectious cycle starts with the viral adsorption and entry into the host cell. Then, the virus is internalized via clathrin/dynamin mediated endocytosis and macropinocytosis. Similar to other viruses, ASF virion is then internalized and incorporated into the endocytic pathway. While the endosomal maturation entails luminal acidification, the decrease in pH acts on the multilayer structure of the virion dissolving the outer capsid. Upon decapsidation, the inner viral membrane is exposed to interact with the limiting membrane of the late endosome for fusion. Viral fusion is then necessary for the egress of incoming virions from endosomes into the cytoplasm, however this remains an intriguing and yet essential process for infection, specifically for the egress of viral nucleic acid into the cytoplasm for replication. ASFV proteins E248R and E199L, located at the exposed inner viral membrane, might be implicated in the fusion step. An interaction between these viral proteins and cellular endosomal proteins such as the Niemann-Pick C type 1 (NPC1) and lysosomal membrane proteins (Lamp-1 and -2) was shown. Furthermore, the silencing of these proteins impaired ASFV infection. It was also observed that NPC1 knock-out cells using CRISPR jeopardized ASFV infection and that the progression and endosomal exit of viral cores was arrested within endosomes at viral entry. These results suggest that the interactions of ASFV proteins with some endosomal proteins might be important for the membrane fusion step. In addition to this, reductions on ASFV infectivity and replication in NPC1 KO cells were accompanied by fewer and smaller viral factories. Our findings pave the way to understanding the role of proteins of the endosomal membrane in ASFV infection.


Assuntos
Vírus da Febre Suína Africana/patogenicidade , Febre Suína Africana/virologia , Endossomos/virologia , Interações Hospedeiro-Patógeno/fisiologia , Proteínas Virais/metabolismo , Vírus da Febre Suína Africana/metabolismo , Animais , Chlorocebus aethiops , Endossomos/metabolismo , Células HEK293 , Humanos , Suínos , Células Vero
5.
Ear Hear ; 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38825740

RESUMO

OBJECTIVES: Objective estimation of minimum hearing levels using auditory brainstem responses (ABRs) elicited by single frequency tone-bursts presented monaurally is currently considered the gold standard. However, the data acquisition time to estimate thresholds (for both ears across four audiometric frequencies) using this method usually exceeds the sleep time (ranging between 35 and 49 minutes) in infants below 4 months, thus providing incomplete information of hearing status which in turn delays timely clinical intervention. Alternate approaches using faster rate, or tone-burst trains have not been readily accepted due to additional hardware and software requirements. We propose here a novel binaural multifrequency stimulation paradigm wherein several stimuli of different frequencies are presented binaurally in an interleaved manner. The rationale here is that the proposed paradigm will increase acquisition efficiency, significantly reduce test time, and improve accuracy by incorporating an automatic wave V detection algorithm. It is important to note that this paradigm can be easily implemented in most commercial ABR systems currently used by most clinicians. DESIGN: Using this binaural multifrequency paradigm, ear specific ABRs were recorded in 30 normal-hearing young adults to both tone-bursts, and narrow-band (NB) iChirps at 500, 1000, 2000, and 4000 Hz. Comparison of ABRs elicited by tone-bursts and narrow-band chirps allowed us to determine if NB iChirps elicited a more robust wave V component compared with the tone-bursts. ABR data were characterized by measures of minimum hearing levels; wave V amplitude; and response detectability for two electrode configurations (high forehead-C7; and high forehead-linked mastoids). RESULTS: Consistent with the research literature, wave V response amplitudes were relatively more robust for NB iChirp stimuli compared with tone-burst stimuli. The easier identification and better detectability of wave V for the NB iChirps at lower stimulus levels contributed to their better thresholds compared with tone-burst elicited responses. It is important to note that binaural multifrequency hearing levels close to minimum hearing levels were determined in approximately 22 minutes using this paradigm-appreciably quicker than the 45 to 60 minutes or longer time required for threshold determination using the conventional single frequency method. CONCLUSIONS: Our novel and simple paradigm using either NB iChirps or tone-bursts provides a reliable method to rapidly estimate the minimum hearing levels across audiometric frequencies for both ears. Incorporation of an automatic wave V detection algorithm increases objectivity and further reduce test time and facilitate early hearing identification and intervention.

6.
Clin Infect Dis ; 76(9): 1628-1635, 2023 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-36571282

RESUMO

BACKGROUND: We evaluated the prevalence of transmitted drug resistance (TDR) to integrase strand-transfer inhibitors (INSTIs) and nucleoside/nucleotide reverse transcriptase inhibitors (NRTIs) and of clinically relevant resistance (CRR) in newly diagnosed people with human immunodeficiency virus (HIV; PWH) naive to antiretroviral therapy (ART) in Europe. METHODS: MeditRes is a consortium that includes ART-naive PWH newly diagnosed in France, Greece, Italy, Portugal, and Spain during 2018-2021. Reverse transcriptase and INSTI sequences were provided by participating centers. To evaluate the prevalence of surveillance drug resistance mutations (SDRM), we used the calibrated population resistance tools from the Stanford HIV website. To evaluate CRR, defined as any resistance level ≥3, we used the Stanford HIV Drug Resistance Database v.9.1 algorithm. RESULTS: We included 2705 PWH, 72% men, median age of 37 years (interquartile range, 30-48); 43.7% were infected by non-B subtypes. The prevalence of INSTI-SDRMs was 0.30% (T66I, T66A, E92Q, E138T, E138K, Y143R, S147G, R263K; all n=1) and the prevalence of NRTI-SDRMs was 5.77% (M184V: 0.85%; M184I: 0.18%; K65R/N: 0.11%; K70E: 0.07%; L74V/I: 0.18%; any thymidine analog mutations: 4.36%). INSTI-CRR was 2.33% (0.15% dolutegravir/bictegravir, 2.29% raltegravir/elvitegravir) and 1.74% to first-line NRTIs (0.89% tenofovir/tenofovir alafenamide, 1.74% abacavir, 1.07% lamivudine/emtricitabine). CONCLUSIONS: We present the most recent data on TDR to integrase-based first-line regimens in Europe. Given the low prevalence of CRR to second-generation integrase inhibitors and to first-line NRTIs during 2018-2021, it is unlikely that newly diagnosed PWH in MeditRes countries would present with baseline resistance to a first-line regimen based on second-generation integrase inhibitors.


Assuntos
Infecções por HIV , Inibidores de Integrase de HIV , Integrase de HIV , HIV-1 , Masculino , Humanos , Adulto , Feminino , Integrases/genética , Inibidores de Integrase de HIV/farmacologia , Inibidores de Integrase de HIV/uso terapêutico , Antirretrovirais/uso terapêutico , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Inibidores da Transcriptase Reversa/farmacologia , Inibidores da Transcriptase Reversa/uso terapêutico , Mutação , Europa (Continente)/epidemiologia , HIV-1/genética , Adenina , Farmacorresistência Viral/genética , Integrase de HIV/genética , Compostos Heterocíclicos com 3 Anéis/uso terapêutico
7.
N Engl J Med ; 382(23): 2207-2219, 2020 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-32492302

RESUMO

BACKGROUND: Rituximab added to chemotherapy prolongs survival among adults with B-cell cancer. Data on its efficacy and safety in children with high-grade, mature B-cell non-Hodgkin's lymphoma are limited. METHODS: We conducted an open-label, international, randomized, phase 3 trial involving patients younger than 18 years of age with high-risk, mature B-cell non-Hodgkin's lymphoma (stage III with an elevated lactate dehydrogenase level or stage IV) or acute leukemia to compare the addition of six doses of rituximab to standard lymphomes malins B (LMB) chemotherapy with standard LMB chemotherapy alone. The primary end point was event-free survival. Overall survival and toxic effects were also assessed. RESULTS: Analyses were based on 328 patients who underwent randomization (164 patients per group); 85.7% of the patients had Burkitt's lymphoma. The median follow-up was 39.9 months. Events were observed in 10 patients in the rituximab-chemotherapy group and in 28 in the chemotherapy group. Event-free survival at 3 years was 93.9% (95% confidence interval [CI], 89.1 to 96.7) in the rituximab-chemotherapy group and 82.3% (95% CI, 75.7 to 87.5) in the chemotherapy group (hazard ratio for primary refractory disease or first occurrence of progression, relapse after response, death from any cause, or second cancer, 0.32; 95% CI, 0.15 to 0.66; one-sided P = 0.00096, which reached the significance level required for this analysis). Eight patients in the rituximab-chemotherapy group died (4 deaths were disease-related, 3 were treatment-related, and 1 was from a second cancer), as did 20 in the chemotherapy group (17 deaths were disease-related, and 3 were treatment-related) (hazard ratio, 0.36; 95% CI, 0.16 to 0.82). The incidence of acute adverse events of grade 4 or higher after prephase treatment was 33.3% in the rituximab-chemotherapy group and 24.2% in the chemotherapy group (P = 0.07); events were related mainly to febrile neutropenia and infection. Approximately twice as many patients in the rituximab-chemotherapy group as in the chemotherapy group had a low IgG level 1 year after trial inclusion. CONCLUSIONS: Rituximab added to standard LMB chemotherapy markedly prolonged event-free survival and overall survival among children and adolescents with high-grade, high-risk, mature B-cell non-Hodgkin's lymphoma and was associated with a higher incidence of hypogammaglobulinemia and, potentially, more episodes of infection. (Funded by the Clinical Research Hospital Program of the French Ministry of Health and others; ClinicalTrials.gov number, NCT01516580.).


Assuntos
Antineoplásicos Imunológicos/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Linfoma de Células B/tratamento farmacológico , Rituximab/administração & dosagem , Adolescente , Antineoplásicos Imunológicos/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Infecções/etiologia , Infusões Intravenosas , Estimativa de Kaplan-Meier , Linfoma de Células B/mortalidade , Masculino , Neutropenia/induzido quimicamente , Intervalo Livre de Progressão , Rituximab/efeitos adversos
8.
PLoS Pathog ; 17(5): e1009576, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-34015061

RESUMO

The efficient spread of SARS-CoV-2 resulted in a unique pandemic in modern history. Despite early identification of ACE2 as the receptor for viral spike protein, much remains to be understood about the molecular events behind viral dissemination. We evaluated the contribution of C-type lectin receptors (CLRS) of antigen-presenting cells, widely present in respiratory mucosa and lung tissue. DC-SIGN, L-SIGN, Langerin and MGL bind to diverse glycans of the spike using multiple interaction areas. Using pseudovirus and cells derived from monocytes or T-lymphocytes, we demonstrate that while virus capture by the CLRs examined does not allow direct cell infection, DC/L-SIGN, among these receptors, promote virus transfer to permissive ACE2+ Vero E6 cells. A glycomimetic compound designed against DC-SIGN, enable inhibition of this process. These data have been then confirmed using authentic SARS-CoV-2 virus and human respiratory cell lines. Thus, we described a mechanism potentiating viral spreading of infection.


Assuntos
COVID-19/transmissão , Lectinas Tipo C/metabolismo , SARS-CoV-2/metabolismo , Glicoproteína da Espícula de Coronavírus/metabolismo , Animais , Antígenos CD/metabolismo , COVID-19/prevenção & controle , Moléculas de Adesão Celular/metabolismo , Linhagem Celular , Chlorocebus aethiops , Humanos , Células Jurkat , Pulmão/metabolismo , Lectinas de Ligação a Manose/metabolismo , Manosídeos/farmacologia , Ligação Proteica/efeitos dos fármacos , Receptores de Superfície Celular/metabolismo , Mucosa Respiratória/metabolismo , Células Vero
9.
J Med Virol ; 95(1): e28268, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36319593

RESUMO

We have measured the humoral response to messenger RNA (mRNA) vaccines in COVID-19 naïve and convalescent individuals. Third doses of mRNA COVID-19 vaccines induced a significant increase in potency and breadth of neutralization against SARS-CoV-2 variants of concern (VoC) including Omicron subvariants BA.1, BA.2, and BA.2.12.1, that were cross-neutralized at comparable levels and less for BA.4/5. This booster effect was especially important in naïve individuals that only after the third dose achieved a level that was comparable with that of vaccinated COVID-19 convalescents except for BA.4/5. Avidity of RBD-binding antibodies was also significantly increased in naïve individuals after the third dose, indicating an association between affinity maturation and cross neutralization of VoC. These results suggest that at least three antigenic stimuli by infection or vaccination with ancestral SARS-CoV-2 sequences are required to induce high avidity cross-neutralizing antibodies. Nevertheless, the circulation of new subvariants such as BA.4/5 with partial resistance to neutralization will have to be closely monitored and eventually consider for future vaccine developments.


Assuntos
COVID-19 , Humanos , COVID-19/prevenção & controle , Vacinas contra COVID-19 , SARS-CoV-2/genética , RNA Mensageiro/genética , Vacinas de mRNA , Anticorpos Neutralizantes , Anticorpos Antivirais , Glicoproteína da Espícula de Coronavírus
10.
J Med Virol ; 95(11): e29225, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37971751

RESUMO

Currently, the majority of the population has been vaccinated against COVID-19 and/or has experienced SARS-CoV-2 infection either before or after vaccination. The immunological response to repeated episodes of infections is not completely clear. We measured SARS-CoV-2 specific neutralization titers by a pseudovirus assay after BA.1 infection and RBD-specific immunoglobulin G (IgG), immunoglobulin A (IgA), and immunoglobulin M (IgM) in a cohort of COVID-19 uninfected and triple vaccinated individuals (breakthrough infection group, BTI) as compared with those previously infected by SARS-CoV-2 (reinfection group, REI) who underwent identical vaccination schedule. SARS-CoV-2 specific neutralizing response after BA.1 infection was significantly higher in the BTI group as compared with the REI. Furthermore, neutralization titers in REI were not significant different from convalescent non reinfected controls. RBD-specific IgG and IgA, but not IgM, were also significantly higher in BTI as compared with REI. Our results show that the first episode of SARS-CoV-2 infection induces a significant increase in neutralizing titers in triple vaccinated individuals and that previous SARS-CoV-2 infection compromise significantly the neutralization response induced by reinfection, even by divergent SARS-CoV-2 variants and at least up to 2 years postinfection, suggesting a fundamental limitation in inducing effective booster through the intranasal route in previously infected individuals.


Assuntos
COVID-19 , Humanos , COVID-19/prevenção & controle , SARS-CoV-2 , Reinfecção , Imunoglobulina A , Imunoglobulina G , Imunoglobulina M , Vacinação , Anticorpos Neutralizantes , Anticorpos Antivirais
11.
Eur J Pediatr ; 182(10): 4647-4654, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37561198

RESUMO

We aimed to describe the outcomes, focusing on the hearing and neurological development, of infants born to mothers with COVID-19 during pregnancy and to evaluate the persistence of maternal antibodies in the first months of life. An observational, prospective study at a tertiary hospital in Madrid (Spain) on infants born to mothers with COVID-19 during pregnancy between March and September 2020 was conducted. A follow-up visit at 1-3 months of age with a physical and neurological examination, cranial ultrasound (cUS), SARS-CoV-2 RT-PCR on nasopharyngeal swab, and SARS-CoV-2 serology were performed. Hearing was evaluated at birth through the automated auditory brainstem response and at six months of age through the auditory steady-state response. A neurodevelopmental examination using the Bayley-III scale was performed at 12 months of age. Of 95 infants studied, neurological examination was normal in all of them at the follow-up visit, as was the cUS in 81/85 (95%) infants, with only mild abnormalities in four of them. Serology was positive in 47/95 (50%) infants, which was not associated with symptoms or severity of maternal infection. No hearing loss was detected, and neurodevelopment was normal in 96% of the infants (median Z score: 0). CONCLUSION: In this cohort, the majority of infants born to mothers with COVID-19 during pregnancy were healthy infants with a normal cUS, no hearing loss, and normal neurodevelopment in the first year of life. Only half of the infants had a positive serological result during the follow-up. WHAT IS KNOWN: • Hearing loss and neurodevelopmental delay in infants born to mothers with COVID-19 during pregnancy has been suggested, although data is inconsistent. Maternal antibody transfer seems to be high, with a rapid decrease during the first weeks of life. WHAT IS NEW: • Most infants born to mothers with COVID-19 during pregnancy had normal hearing screening, cranial ultrasound, and neurodevelopmental status at 12 months of life. Antibodies against SARS-CoV-2 were only detected in 50% of the infants at two months of life.


Assuntos
COVID-19 , Complicações Infecciosas na Gravidez , Recém-Nascido , Gravidez , Feminino , Humanos , Lactente , SARS-CoV-2 , COVID-19/diagnóstico , Estudos Prospectivos , Espanha/epidemiologia , Complicações Infecciosas na Gravidez/diagnóstico , Complicações Infecciosas na Gravidez/prevenção & controle , Transmissão Vertical de Doenças Infecciosas/prevenção & controle
12.
J Infect Dis ; 227(1): 35-39, 2022 12 28.
Artigo em Inglês | MEDLINE | ID: mdl-35921532

RESUMO

Several anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) monoclonal antibodies (mAbs) have received emergency authorization for coronavirus disease 2019 (COVID-19) treatment. However, most of these mAbs are not active against the highly mutated Omicron SARS-CoV-2 subvariants. We have tested a polyclonal approach of equine anti-SARS-CoV-2 F(ab')2 antibodies that achieved a high level of neutralizing potency against all SARS-CoV-2 variants of concern tested including Omicron BA.1, BA.2, BA.2.12 and BA.4/5. A repertoire of antibodies targeting conserved epitopes in different regions of the spike protein could plausibly account for this remarkable breadth of neutralization. These results warrant the clinical investigation of equine polyclonal F(ab')2 antibodies as a novel therapeutic strategy against COVID-19.


Assuntos
COVID-19 , SARS-CoV-2 , Animais , Cavalos , Humanos , SARS-CoV-2/genética , Anticorpos Monoclonais , Anticorpos Antivirais , Glicoproteína da Espícula de Coronavírus/genética , Anticorpos Neutralizantes
13.
J Infect Dis ; 225(11): 1905-1908, 2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-34963008

RESUMO

We have investigated the evolution of the neutralizing response against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants at 8 months after Pfizer-BNT162b2 vaccination in coronavirus disease 2019 (COVID-19)-naive (n = 21) and COVID-19-convalescent (n = 21) individuals. Neutralizing levels declined for all variants (range 2- to 3.7-fold). Eight months after vaccination, a significant proportion (4/21) of naive individuals lacked detectable neutralizing activity against the highly transmissible SARS-CoV-2 delta variant. In the convalescent group, the impressive high initial humoral response resulted in detectable neutralizing antibody levels against all variants throughout this period.


Assuntos
COVID-19 , SARS-CoV-2 , Anticorpos Neutralizantes , Anticorpos Antivirais , Vacina BNT162 , COVID-19/prevenção & controle , Humanos , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus , Vacinação
14.
Blood ; 135(4): 274-286, 2020 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-31738823

RESUMO

Pediatric large B-cell lymphomas (LBCLs) share morphological and phenotypic features with adult types but have better prognosis. The higher frequency of some subtypes such as LBCL with IRF4 rearrangement (LBCL-IRF4) in children suggests that some age-related biological differences may exist. To characterize the genetic and molecular heterogeneity of these tumors, we studied 31 diffuse LBCLs (DLBCLs), not otherwise specified (NOS); 20 LBCL-IRF4 cases; and 12 cases of high-grade B-cell lymphoma (HGBCL), NOS in patients ≤25 years using an integrated approach, including targeted gene sequencing, copy-number arrays, and gene expression profiling. Each subgroup displayed different molecular profiles. LBCL-IRF4 had frequent mutations in IRF4 and NF-κB pathway genes (CARD11, CD79B, and MYD88), losses of 17p13 and gains of chromosome 7, 11q12.3-q25, whereas DLBCL, NOS was predominantly of germinal center B-cell (GCB) subtype and carried gene mutations similar to the adult counterpart (eg, SOCS1 and KMT2D), gains of 2p16/REL, and losses of 19p13/CD70. A subset of HGBCL, NOS displayed recurrent alterations of Burkitt lymphoma-related genes such as MYC, ID3, and DDX3X and homozygous deletions of 9p21/CDKN2A, whereas other cases were genetically closer to GCB DLBCL. Factors related to unfavorable outcome were age >18 years; activated B-cell (ABC) DLBCL profile, HGBCL, NOS, high genetic complexity, 1q21-q44 gains, 2p16/REL gains/amplifications, 19p13/CD70 homozygous deletions, and TP53 and MYC mutations. In conclusion, these findings further unravel the molecular heterogeneity of pediatric and young adult LBCL, improve the classification of this group of tumors, and provide new parameters for risk stratification.


Assuntos
Fatores Reguladores de Interferon/genética , Linfoma Difuso de Grandes Células B/genética , Mutação , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Linfoma Difuso de Grandes Células B/diagnóstico , Linfoma Difuso de Grandes Células B/patologia , Masculino , Prognóstico , Transcriptoma , Adulto Jovem
15.
Acta Neuropathol ; 143(1): 93-104, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34797422

RESUMO

Malformations of cortical development (MCD) comprise a broad spectrum of structural brain lesions frequently associated with epilepsy. Disease definition and diagnosis remain challenging and are often prone to arbitrary judgment. Molecular classification of histopathological entities may help rationalize the diagnostic process. We present a retrospective, multi-center analysis of genome-wide DNA methylation from human brain specimens obtained from epilepsy surgery using EPIC 850 K BeadChip arrays. A total of 308 samples were included in the study. In the reference cohort, 239 formalin-fixed and paraffin-embedded (FFPE) tissue samples were histopathologically classified as MCD, including 12 major subtype pathologies. They were compared to 15 FFPE samples from surgical non-MCD cortices and 11 FFPE samples from post-mortem non-epilepsy controls. We applied three different statistical approaches to decipher the DNA methylation pattern of histopathological MCD entities, i.e., pairwise comparison, machine learning, and deep learning algorithms. Our deep learning model, which represented a shallow neuronal network, achieved the highest level of accuracy. A test cohort of 43 independent surgical samples from different epilepsy centers was used to test the precision of our DNA methylation-based MCD classifier. All samples from the test cohort were accurately assigned to their disease classes by the algorithm. These data demonstrate DNA methylation-based MCD classification suitability across major histopathological entities amenable to epilepsy surgery and age groups and will help establish an integrated diagnostic classification scheme for epilepsy-associated MCD.


Assuntos
Metilação de DNA , Aprendizado Profundo , Malformações do Desenvolvimento Cortical/classificação , Malformações do Desenvolvimento Cortical/diagnóstico , Adolescente , Adulto , Criança , Pré-Escolar , Epilepsia/etiologia , Feminino , Humanos , Lactente , Masculino , Malformações do Desenvolvimento Cortical/genética , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
16.
Int J Mol Sci ; 23(9)2022 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-35563489

RESUMO

The synthesis of new biocompatible antiviral materials to fight against the development of multidrug resistance is being widely explored. Due to their unique globular structure and excellent properties, [60]fullerene-based antivirals are very promising bioconjugates. In this work, fullerene derivatives with different topologies and number of glycofullerene units were synthesized by using a SPAAC copper free strategy. This procedure allowed the synthesis of compounds 1-3, containing from 20 to 40 mannose units, in a very efficient manner and in short reaction times under MW irradiation. The glycoderivatives were studied in an infection assay by a pseudotyped viral particle with Ebola virus GP1. The results obtained show that these glycofullerene oligomers are efficient inhibitors of EBOV infection with IC50s in the nanomolar range. In particular, compound 3, with four glycofullerene moieties, presents an outstanding relative inhibitory potency (RIP). We propose that this high RIP value stems from the appropriate topological features that efficiently interact with DC-SIGN.


Assuntos
Ebolavirus , Fulerenos , Doença pelo Vírus Ebola , Antivirais/uso terapêutico , Fulerenos/química , Doença pelo Vírus Ebola/tratamento farmacológico , Humanos , Manose/química
17.
Environ Monit Assess ; 194(2): 90, 2022 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-35022957

RESUMO

In recent years, Brazil has become a major global contributor to the occurrence of national fires and greenhouse gas emissions. Therefore, this study aimed to evaluate the fire foci data of the past 20 years to determine their relationship with climatic variables in various Brazilian regions. The variables evaluated included fire foci, land surface temperature, rainfall, and standardized precipitation index, which were obtained via remote sensing from 2000 to 2019. The data were subjected to trend analyses (Mann-Kendall and Pettitt tests) and a multivariate analysis of canonical variables for evaluation. The results showed that the Midwest and North regions had the highest occurrence of fire foci throughout the study period, and that the North region had the highest accumulated annual rainfall. Thus, these regions require specific public policies to prevent future fires. Overall, the Midwest, Southeast, and South regions exhibit significant increasing fire foci tendencies. Our results reveal that this trend is related to the El Niño-Southern Oscillation (ENSO) phenomena, which alter climatic variables such as precipitation, land surface temperature, and the standardized precipitation index. Finally, the sugarcane growing area had a significant linear relationship with fire foci in the Southeast region, especially in the state of São Paulo, the major national sugarcane producer.


Assuntos
Monitoramento Ambiental , Incêndios , Brasil , El Niño Oscilação Sul , Análise Multivariada
18.
J Antimicrob Chemother ; 76(12): 3263-3271, 2021 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-34459889

RESUMO

BACKGROUND: Previously selected lamivudine resistance-associated mutations (RAMs) may remain archived within the proviral HIV-DNA. OBJECTIVES: To evaluate the ability of proviral DNA genotyping to detect lamivudine RAMs in HIV-1 virologically suppressed participants; the correlation between Sanger and next generation sequencing (NGS); and predictive factors for detection of lamivudine RAMs in proviral DNA. METHODS: Cross-sectional study of participants on stable antiretroviral therapy and suppressed for ≥1 year. Analysis of proviral DNA was performed by Sanger sequencing in whole blood and by NGS in PBMCs. RESULTS: We analysed samples from 102 subjects (52 with and 50 without lamivudine RAMs in historical plasma RNA-genotypes). Among participants with previous lamivudine resistance, Sanger sequencing detected RAMs in 26.9%. Detection rates significantly increased using NGS: 47.9%, 64.6%, 75% and 87.5% with the 20%, 10%, 5% and 1% thresholds, respectively. As for participants without historical lamivudine resistance, Sanger detected the RAMs in 1/49 (2%), and NGS (5% threshold) in 8/45 (17.8%). Multivariate models fitted to the whole population revealed that having a history of lamivudine resistance was a risk factor for detection of lamivudine RAMs by NGS. Among participants with historical lamivudine resistance, multivariate analysis showed that a longer time since HIV diagnosis was associated with persistence of archived mutations by NGS at thresholds of >10% [OR 1.10 (95% CI: 1.00-1.24)] and >5% [OR 1.16 (95% CI: 1.02-1.32)]. CONCLUSIONS: Proviral DNA Sanger sequencing does not detect the majority of historical lamivudine RAMs. NGS increases the sensitivity of detection at lower thresholds, although the relevance of these minority populations with lamivudine RAMs needs further evaluation.


Assuntos
Fármacos Anti-HIV , Infecções por HIV , Fármacos Anti-HIV/uso terapêutico , Estudos Transversais , Farmacorresistência Viral , Genótipo , Técnicas de Genotipagem , Infecções por HIV/tratamento farmacológico , Humanos , Lamivudina/uso terapêutico , Mutação , Carga Viral
19.
J Antimicrob Chemother ; 76(3): 738-742, 2021 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-33200210

RESUMO

BACKGROUND: In the ART-PRO pilot trial there were no virological failures through 48 weeks of treatment with dolutegravir plus lamivudine in suppressed individuals with and without archived lamivudine resistance-associated mutations (RAMs) detected through next-generation sequencing (NGS) but without evidence of lamivudine RAMs in baseline proviral DNA population sequencing. OBJECTIVES: To present 96 week results from ART-PRO. METHODS: Open-label, single-arm pilot trial. At baseline, all participants switched to dolutegravir plus lamivudine. Participants were excluded if proviral DNA population genotyping detected lamivudine RAMs. To detect resistance minority variants, proviral DNA NGS was retrospectively performed from baseline samples. For this analysis the efficacy endpoint was the proportion of participants with <50 HIV-1 RNA copies/mL at week 96. Safety and tolerability outcomes were incidence of adverse events and treatment discontinuations. RESULTS: Forty-one participants were included, 21 with lamivudine RAMs in historical plasma RNA genotypes. Baseline proviral DNA NGS detected lamivudine RAMs (M184V/I and/or K65R/E/N) above a 5% threshold in 71.4% (15/21) and 15% (3/20) of participants with and without history of lamivudine resistance, respectively. At 96 weeks, 90.2% of participants achieved the efficacy endpoint. Between week 48 and 96 there was one discontinuation due to consent withdrawal and no discontinuations related to adverse events. Two participants had a transient viral rebound, both re-suppressed on dolutegravir plus lamivudine. Through week 96, there were no virological failures. CONCLUSIONS: In this pilot trial, dolutegravir plus lamivudine maintained virological suppression at 96 weeks despite historical lamivudine resistance and persisting archived minority lamivudine RAMs.


Assuntos
Fármacos Anti-HIV , Infecções por HIV , HIV-1 , Adulto , Fármacos Anti-HIV/uso terapêutico , Quimioterapia Combinada , Infecções por HIV/tratamento farmacológico , HIV-1/genética , Compostos Heterocíclicos com 3 Anéis , Humanos , Lamivudina/uso terapêutico , Oxazinas , Projetos Piloto , Piperazinas/uso terapêutico , Piridonas , Estudos Retrospectivos , Carga Viral
20.
Eur J Pediatr ; 180(7): 2099-2106, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33606120

RESUMO

Fever without source (FWS) in infants is a frequent cause of consultation at the emergency department, and the emergence of SARS-CoV-2 could affect the approach to those infants. The aim of this study is to define the clinical characteristics and rates of bacterial coinfections of infants < 90 days with FWS as the first manifestation of SARS-CoV-2 infection. This is a cross-sectional study of infants under 90 days of age with FWS and positive SARS-CoV2 PCR in nasopharyngeal swab/aspirate, attended at the emergency departments of 49 Spanish hospitals (EPICO-AEP cohort) from March 1 to June 26, 2020. Three hundred and thirty-three children with COVID-19 were included in EPICO-AEP. A total of 67/336 (20%) were infants less than 90 days old, and 27/67(40%) presented with FWS. Blood cultures were performed in 24/27(89%) and were negative in all but one (4%) who presented a Streptococcus mitis bacteremia. Urine culture was performed in 26/27(97%) children and was negative in all, except in two (7%) patients. Lumbar puncture was performed in 6/27(22%) cases, with no growth of bacteria. Two children had bacterial coinfections: 1 had UTI and bacteremia, and 1 had UTI. C-reactive was protein over 20 mg/L in two children (one with bacterial coinfection), and procalcitonin was normal in all. One child was admitted to the pediatric intensive care unit because of apnea episodes. No patients died.Conclusion: FWS was frequent in infants under 90 days of age with SARS-CoV-2 infection. Standardized markers to rule out bacterial infections remain useful in this population, and the outcome is generally good. What is Known: • Fever without source (FWS) in infants is a common cause of consultation at the emergency department, and young infants have a higher risk of serious bacterial infections (SBI). • The emergence of the new coronavirus SARS-CoV-2 could affect the approach to young infants with FWS in the emergency department. management of those children is a challenge because information about bacterial coinfection and prognosis is scarce. What is New: • SARS-CoV-2 infection should be ruled out in young infants (< 90 days of age) with FWS in areas with community transmission. • Bacterial coinfection rarely coexists in those infants. • Inflammatory markers were not increased in children without bacterial coinfection. • Outcome is good in most patients.


Assuntos
COVID-19 , SARS-CoV-2 , Criança , Estudos Transversais , Febre/epidemiologia , Febre/etiologia , Humanos , Lactente , RNA Viral
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