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1.
Nature ; 626(8001): 1094-1101, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38383783

RESUMEN

Persistent SARS-CoV-2 infections may act as viral reservoirs that could seed future outbreaks1-5, give rise to highly divergent lineages6-8 and contribute to cases with post-acute COVID-19 sequelae (long COVID)9,10. However, the population prevalence of persistent infections, their viral load kinetics and evolutionary dynamics over the course of infections remain largely unknown. Here, using viral sequence data collected as part of a national infection survey, we identified 381 individuals with SARS-CoV-2 RNA at high titre persisting for at least 30 days, of which 54 had viral RNA persisting at least 60 days. We refer to these as 'persistent infections' as available evidence suggests that they represent ongoing viral replication, although the persistence of non-replicating RNA cannot be ruled out in all. Individuals with persistent infection had more than 50% higher odds of self-reporting long COVID than individuals with non-persistent infection. We estimate that 0.1-0.5% of infections may become persistent with typically rebounding high viral loads and last for at least 60 days. In some individuals, we identified many viral amino acid substitutions, indicating periods of strong positive selection, whereas others had no consensus change in the sequences for prolonged periods, consistent with weak selection. Substitutions included mutations that are lineage defining for SARS-CoV-2 variants, at target sites for monoclonal antibodies and/or are commonly found in immunocompromised people11-14. This work has profound implications for understanding and characterizing SARS-CoV-2 infection, epidemiology and evolution.


Asunto(s)
COVID-19 , Encuestas Epidemiológicas , Infección Persistente , SARS-CoV-2 , Humanos , Sustitución de Aminoácidos , Anticuerpos Monoclonales/inmunología , COVID-19/epidemiología , COVID-19/virología , Evolución Molecular , Huésped Inmunocomprometido/inmunología , Mutación , Infección Persistente/epidemiología , Infección Persistente/virología , Síndrome Post Agudo de COVID-19/epidemiología , Síndrome Post Agudo de COVID-19/virología , Prevalencia , ARN Viral/análisis , ARN Viral/genética , SARS-CoV-2/química , SARS-CoV-2/clasificación , SARS-CoV-2/genética , SARS-CoV-2/inmunología , SARS-CoV-2/aislamiento & purificación , Selección Genética , Autoinforme , Factores de Tiempo , Carga Viral , Replicación Viral
2.
Nature ; 603(7902): 706-714, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35104837

RESUMEN

The SARS-CoV-2 Omicron BA.1 variant emerged in 20211 and has multiple mutations in its spike protein2. Here we show that the spike protein of Omicron has a higher affinity for ACE2 compared with Delta, and a marked change in its antigenicity increases Omicron's evasion of therapeutic monoclonal and vaccine-elicited polyclonal neutralizing antibodies after two doses. mRNA vaccination as a third vaccine dose rescues and broadens neutralization. Importantly, the antiviral drugs remdesivir and molnupiravir retain efficacy against Omicron BA.1. Replication was similar for Omicron and Delta virus isolates in human nasal epithelial cultures. However, in lung cells and gut cells, Omicron demonstrated lower replication. Omicron spike protein was less efficiently cleaved compared with Delta. The differences in replication were mapped to the entry efficiency of the virus on the basis of spike-pseudotyped virus assays. The defect in entry of Omicron pseudotyped virus to specific cell types effectively correlated with higher cellular RNA expression of TMPRSS2, and deletion of TMPRSS2 affected Delta entry to a greater extent than Omicron. Furthermore, drug inhibitors targeting specific entry pathways3 demonstrated that the Omicron spike inefficiently uses the cellular protease TMPRSS2, which promotes cell entry through plasma membrane fusion, with greater dependency on cell entry through the endocytic pathway. Consistent with suboptimal S1/S2 cleavage and inability to use TMPRSS2, syncytium formation by the Omicron spike was substantially impaired compared with the Delta spike. The less efficient spike cleavage of Omicron at S1/S2 is associated with a shift in cellular tropism away from TMPRSS2-expressing cells, with implications for altered pathogenesis.


Asunto(s)
COVID-19/patología , COVID-19/virología , Fusión de Membrana , SARS-CoV-2/metabolismo , SARS-CoV-2/patogenicidad , Serina Endopeptidasas/metabolismo , Internalización del Virus , Adulto , Anciano , Anciano de 80 o más Años , Enzima Convertidora de Angiotensina 2/metabolismo , Animales , Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/inmunología , COVID-19/inmunología , Vacunas contra la COVID-19/inmunología , Línea Celular , Membrana Celular/metabolismo , Membrana Celular/virología , Chlorocebus aethiops , Convalecencia , Femenino , Humanos , Sueros Inmunes/inmunología , Intestinos/patología , Intestinos/virología , Pulmón/patología , Pulmón/virología , Masculino , Persona de Mediana Edad , Mutación , Mucosa Nasal/patología , Mucosa Nasal/virología , SARS-CoV-2/efectos de los fármacos , SARS-CoV-2/inmunología , Glicoproteína de la Espiga del Coronavirus/genética , Glicoproteína de la Espiga del Coronavirus/metabolismo , Técnicas de Cultivo de Tejidos , Virulencia , Replicación Viral
3.
Nature ; 592(7853): 277-282, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33545711

RESUMEN

The spike protein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is critical for virus infection through the engagement of the human ACE2 protein1 and is a major antibody target. Here we show that chronic infection with SARS-CoV-2 leads to viral evolution and reduced sensitivity to neutralizing antibodies in an immunosuppressed individual treated with convalescent plasma, by generating whole-genome ultra-deep sequences for 23 time points that span 101 days and using in vitro techniques to characterize the mutations revealed by sequencing. There was little change in the overall structure of the viral population after two courses of remdesivir during the first 57 days. However, after convalescent plasma therapy, we observed large, dynamic shifts in the viral population, with the emergence of a dominant viral strain that contained a substitution (D796H) in the S2 subunit and a deletion (ΔH69/ΔV70) in the S1 N-terminal domain of the spike protein. As passively transferred serum antibodies diminished, viruses with the escape genotype were reduced in frequency, before returning during a final, unsuccessful course of convalescent plasma treatment. In vitro, the spike double mutant bearing both ΔH69/ΔV70 and D796H conferred modestly decreased sensitivity to convalescent plasma, while maintaining infectivity levels that were similar to the wild-type virus.The spike substitution mutant D796H appeared to be the main contributor to the decreased susceptibility to neutralizing antibodies, but this mutation resulted in an infectivity defect. The spike deletion mutant ΔH69/ΔV70 had a twofold higher level of infectivity than wild-type SARS-CoV-2, possibly compensating for the reduced infectivity of the D796H mutation. These data reveal strong selection on SARS-CoV-2 during convalescent plasma therapy, which is associated with the emergence of viral variants that show evidence of reduced susceptibility to neutralizing antibodies in immunosuppressed individuals.


Asunto(s)
Tratamiento Farmacológico de COVID-19 , COVID-19/terapia , COVID-19/virología , Evolución Molecular , Mutagénesis/efectos de los fármacos , SARS-CoV-2/efectos de los fármacos , SARS-CoV-2/genética , Adenosina Monofosfato/análogos & derivados , Adenosina Monofosfato/farmacología , Adenosina Monofosfato/uso terapéutico , Anciano , Alanina/análogos & derivados , Alanina/farmacología , Alanina/uso terapéutico , Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/inmunología , COVID-19/inmunología , Enfermedad Crónica , Genoma Viral/efectos de los fármacos , Genoma Viral/genética , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Evasión Inmune/efectos de los fármacos , Evasión Inmune/genética , Evasión Inmune/inmunología , Tolerancia Inmunológica/efectos de los fármacos , Tolerancia Inmunológica/inmunología , Inmunización Pasiva , Terapia de Inmunosupresión , Masculino , Proteínas Mutantes/química , Proteínas Mutantes/genética , Proteínas Mutantes/inmunología , Mutación , Filogenia , SARS-CoV-2/inmunología , SARS-CoV-2/metabolismo , Glicoproteína de la Espiga del Coronavirus/química , Glicoproteína de la Espiga del Coronavirus/genética , Glicoproteína de la Espiga del Coronavirus/inmunología , Factores de Tiempo , Carga Viral/efectos de los fármacos , Esparcimiento de Virus , Sueroterapia para COVID-19
4.
Nature ; 593(7857): 136-141, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33706364

RESUMEN

Transmission of SARS-CoV-2 is uncontrolled in many parts of the world; control is compounded in some areas by the higher transmission potential of the B.1.1.7 variant1, which has now been reported in 94 countries. It is unclear whether the response of the virus to vaccines against SARS-CoV-2 on the basis of the prototypic strain will be affected by the mutations found in B.1.1.7. Here we assess the immune responses of individuals after vaccination with the mRNA-based vaccine BNT162b22. We measured neutralizing antibody responses after the first and second immunizations using pseudoviruses that expressed the wild-type spike protein or a mutated spike protein that contained the eight amino acid changes found in the B.1.1.7 variant. The sera from individuals who received the vaccine exhibited a broad range of neutralizing titres against the wild-type pseudoviruses that were modestly reduced against the B.1.1.7 variant. This reduction was also evident in sera from some patients who had recovered from COVID-19. Decreased neutralization of the B.1.1.7 variant was also observed for monoclonal antibodies that target the N-terminal domain (9 out of 10) and the receptor-binding motif (5 out of 31), but not for monoclonal antibodies that recognize the receptor-binding domain that bind outside the receptor-binding motif. Introduction of the mutation that encodes the E484K substitution in the B.1.1.7 background to reflect a newly emerged variant of concern (VOC 202102/02) led to a more-substantial loss of neutralizing activity by vaccine-elicited antibodies and monoclonal antibodies (19 out of 31) compared with the loss of neutralizing activity conferred by the mutations in B.1.1.7 alone. The emergence of the E484K substitution in a B.1.1.7 background represents a threat to the efficacy of the BNT162b2 vaccine.


Asunto(s)
Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/inmunología , Vacunas contra la COVID-19/inmunología , COVID-19/inmunología , COVID-19/terapia , SARS-CoV-2/inmunología , Glicoproteína de la Espiga del Coronavirus/inmunología , Vacunas Sintéticas/inmunología , Anciano , Anciano de 80 o más Años , Enzima Convertidora de Angiotensina 2/metabolismo , Anticuerpos Monoclonales/inmunología , Anticuerpos Monoclonales/aislamiento & purificación , Anticuerpos Neutralizantes/aislamiento & purificación , Anticuerpos Antivirales/aislamiento & purificación , COVID-19/metabolismo , COVID-19/virología , Femenino , Células HEK293 , Humanos , Evasión Inmune/genética , Evasión Inmune/inmunología , Inmunización Pasiva , Masculino , Persona de Mediana Edad , Modelos Moleculares , Mutación , Pruebas de Neutralización , SARS-CoV-2/genética , Glicoproteína de la Espiga del Coronavirus/química , Glicoproteína de la Espiga del Coronavirus/genética , Glicoproteína de la Espiga del Coronavirus/metabolismo , Vacunas Sintéticas/administración & dosificación , Sueroterapia para COVID-19 , Vacunas de ARNm
5.
Nature ; 599(7883): 114-119, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34488225

RESUMEN

The B.1.617.2 (Delta) variant of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was first identified in the state of Maharashtra in late 2020 and spread throughout India, outcompeting pre-existing lineages including B.1.617.1 (Kappa) and B.1.1.7 (Alpha)1. In vitro, B.1.617.2 is sixfold less sensitive to serum neutralizing antibodies from recovered individuals, and eightfold less sensitive to vaccine-elicited antibodies, compared with wild-type Wuhan-1 bearing D614G. Serum neutralizing titres against B.1.617.2 were lower in ChAdOx1 vaccinees than in BNT162b2 vaccinees. B.1.617.2 spike pseudotyped viruses exhibited compromised sensitivity to monoclonal antibodies to the receptor-binding domain and the amino-terminal domain. B.1.617.2 demonstrated higher replication efficiency than B.1.1.7 in both airway organoid and human airway epithelial systems, associated with B.1.617.2 spike being in a predominantly cleaved state compared with B.1.1.7 spike. The B.1.617.2 spike protein was able to mediate highly efficient syncytium formation that was less sensitive to inhibition by neutralizing antibody, compared with that of wild-type spike. We also observed that B.1.617.2 had higher replication and spike-mediated entry than B.1.617.1, potentially explaining the B.1.617.2 dominance. In an analysis of more than 130 SARS-CoV-2-infected health care workers across three centres in India during a period of mixed lineage circulation, we observed reduced ChAdOx1 vaccine effectiveness against B.1.617.2 relative to non-B.1.617.2, with the caveat of possible residual confounding. Compromised vaccine efficacy against the highly fit and immune-evasive B.1.617.2 Delta variant warrants continued infection control measures in the post-vaccination era.


Asunto(s)
Evasión Inmune , SARS-CoV-2/crecimiento & desarrollo , SARS-CoV-2/inmunología , Replicación Viral/inmunología , Anticuerpos Neutralizantes/inmunología , Vacunas contra la COVID-19/inmunología , Fusión Celular , Línea Celular , Femenino , Personal de Salud , Humanos , India , Cinética , Masculino , Glicoproteína de la Espiga del Coronavirus/metabolismo , Vacunación
6.
J Antimicrob Chemother ; 78(8): 2000-2007, 2023 08 02.
Artículo en Inglés | MEDLINE | ID: mdl-37367727

RESUMEN

BACKGROUND: Due to the high prevalence of resistance to NNRTI-based ART since 2018, consolidated recommendations from the WHO have indicated dolutegravir as the preferred drug of choice for HIV treatment globally. There is a paucity of resistance outcome data from HIV-1 non-B subtypes circulating across West Africa. AIMS: We characterized the mutational profiles of persons living with HIV from a cross-sectional cohort in North-East Nigeria failing a dolutegravir-based ART regimen. METHODS: WGS of plasma samples collected from 61 HIV-1-infected participants following virological failure of dolutegravir-based ART were sequenced using the Illumina platform. Sequencing was successfully completed for samples from 55 participants. Following quality control, 33 full genomes were analysed from participants with a median age of 40 years and median time on ART of 9 years. HIV-1 subtyping was performed using SNAPPy. RESULTS: Most participants had mutational profiles reflective of exposure to previous first- and second-line ART regimens comprised NRTIs and NNRTIs. More than half of participants had one or more drug resistance-associated mutations (DRMs) affecting susceptibility to NRTIs (17/33; 52%) and NNRTIs (24/33; 73%). Almost a quarter of participants (8/33; 24.4%) had one or more DRMs affecting tenofovir susceptibility. Only one participant, infected with HIV-1 subtype G, had evidence of DRMs affecting dolutegravir susceptibility-this was characterized by the T66A, G118R, E138K and R263K mutations. CONCLUSIONS: This study found a low prevalence of resistance to dolutegravir; the data are therefore supportive of the continual rollout of dolutegravir as the primary first-line regimen for ART-naive participants and the preferred switch to second-line ART across the region. However, population-level, longer-term data collection on dolutegravir outcomes are required to further guide implementation and policy action across the region.


Asunto(s)
Infecciones por VIH , Inhibidores de Integrasa VIH , Humanos , Adulto , Estudios Transversales , Infecciones por VIH/tratamiento farmacológico , Compuestos Heterocíclicos con 3 Anillos/uso terapéutico , Compuestos Heterocíclicos con 3 Anillos/farmacología , Oxazinas/uso terapéutico , Piridonas/uso terapéutico , Inhibidores de Integrasa VIH/uso terapéutico , Inhibidores de Integrasa VIH/farmacología , Mutación , Farmacorresistencia Viral/genética , Integrasas/genética
9.
J Infect Dis ; 224(6): 989-994, 2021 09 17.
Artículo en Inglés | MEDLINE | ID: mdl-34260717

RESUMEN

The SARS-CoV-2 B.1.617 variant emerged in the Indian state of Maharashtra in late 2020. There have been fears that 2 key mutations seen in the receptor-binding domain, L452R and E484Q, would have additive effects on evasion of neutralizing antibodies. We report that spike bearing L452R and E484Q confers modestly reduced sensitivity to BNT162b2 mRNA vaccine-elicited antibodies following either first or second dose. The effect is similar in magnitude to the loss of sensitivity conferred by L452R or E484Q alone. These data demonstrate reduced sensitivity to vaccine-elicited neutralizing antibodies by L452R and E484Q but lack of synergistic loss of sensitivity.


Asunto(s)
COVID-19/inmunología , COVID-19/virología , Evasión Inmune , Mutación , SARS-CoV-2/genética , Enzima Convertidora de Angiotensina 2 , Animales , Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/sangre , Anticuerpos Antivirales/inmunología , Vacuna BNT162 , Vacunas contra la COVID-19/inmunología , Chlorocebus aethiops , Células HEK293 , Humanos , India , Unión Proteica , SARS-CoV-2/inmunología , Serina Endopeptidasas , Glicoproteína de la Espiga del Coronavirus/química , Glicoproteína de la Espiga del Coronavirus/genética , Glicoproteína de la Espiga del Coronavirus/inmunología , Células Vero
10.
J Med Virol ; 93(2): 1013-1022, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-32729939

RESUMEN

BACKGROUND: There is currently very limited information on the nature and prevalence of post-COVID-19 symptoms after hospital discharge. METHODS: A purposive sample of 100 survivors discharged from a large University hospital were assessed 4 to 8 weeks after discharge by a multidisciplinary team of rehabilitation professionals using a specialist telephone screening tool designed to capture symptoms and impact on daily life. EQ-5D-5L telephone version was also completed. RESULTS: Participants were between 29 and 71 days (mean 48 days) postdischarge from hospital. Thirty-two participants required treatment in intensive care unit (ICU group) and 68 were managed in hospital wards without needing ICU care (ward group). New illness-related fatigue was the most common reported symptom by 72% participants in ICU group and 60.3% in ward group. The next most common symptoms were breathlessness (65.6% in ICU group and 42.6% in ward group) and psychological distress (46.9% in ICU group and 23.5% in ward group). There was a clinically significant drop in EQ5D in 68.8% in ICU group and in 45.6% in ward group. CONCLUSIONS: This is the first study from the United Kingdom reporting on postdischarge symptoms. We recommend planning rehabilitation services to manage these symptoms appropriately and maximize the functional return of COVID-19 survivors.


Asunto(s)
COVID-19/complicaciones , COVID-19/rehabilitación , Alta del Paciente/estadística & datos numéricos , Sobrevivientes/estadística & datos numéricos , Adulto , Anciano , Anciano de 80 o más Años , COVID-19/epidemiología , Cuidados Críticos , Estudios Transversales , Femenino , Hospitales Universitarios/estadística & datos numéricos , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Reino Unido/epidemiología , Adulto Joven
11.
J Antimicrob Chemother ; 75(6): 1575-1579, 2020 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-32105319

RESUMEN

OBJECTIVES: HIV-1 integrase inhibitors are recommended as first-line therapy by WHO, though efficacy and resistance data for non-B subtypes are limited. Two recent trials have identified the integrase L74I mutation to be associated with integrase inhibitor treatment failure in HIV-1 non-B subtypes. We sought to define the prevalence of integrase resistance mutations, including L74I, in West Africa. METHODS: We studied a Nigerian cohort of recipients prior to and during receipt of second-line PI-based therapy, who were integrase inhibitor-naive. Illumina next-generation sequencing with target enrichment was used on stored plasma samples. Drug resistance was interpreted using the Stanford Resistance Database and the IAS-USA 2019 mutation lists. RESULTS: Of 115 individuals, 59.1% harboured CRF02_AG HIV-1 and 40.9% harboured subtype G HIV-1. Four participants had major IAS-USA integrase resistance-associated mutations detected at low levels (2%-5% frequency). Two had Q148K minority variants and two had R263K (one of whom also had L74I). L74I was detected in plasma samples at over 2% frequency in 40% (46/115). Twelve (26.1%) had low-level minority variants of between 2% and 20% of the viral population sampled. The remaining 34 (73.9%) had L74I present at >20% frequency. L74I was more common among those with subtype G infection (55.3%, 26/47) than those with CRF02_AG infection (29.4%, 20/68) (P = 0.005). CONCLUSIONS: HIV-1 subtypes circulating in West Africa appear to have very low prevalence of major integrase mutations, but significant prevalence of L74I. A combination of in vitro and clinical studies is warranted to understand the potential implications.


Asunto(s)
Infecciones por VIH , Inhibidores de Integrasa VIH , Integrasa de VIH , VIH-1 , África Occidental , Farmacorresistencia Viral/genética , Genotipo , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/epidemiología , Integrasa de VIH/genética , Inhibidores de Integrasa VIH/farmacología , Inhibidores de Integrasa VIH/uso terapéutico , VIH-1/genética , Humanos , Mutación , Prevalencia
12.
Epilepsia ; 59(4): 844-853, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29574898

RESUMEN

OBJECTIVE: Growing evidence suggests that psychological treatments are effective for improving outcomes in both epilepsy and psychogenic nonepileptic seizures (PNES). However, the risk of in-session seizures may cause concerns about safety and about seizures disrupting treatment. This study explores the risk of in-session seizures in patients with epilepsy and those with PNES, the timings of seizures during psychological therapy, and the responses of therapists to seizures. METHODS: Consecutive patients with epilepsy or PNES attending 2 neurology centers in the United Kingdom for psychological treatment to help with their seizure disorders were studied. Information about seizures during outpatient psychological therapy sessions was gathered using a 12-item pro forma. RESULTS: Ninety-seven patients with epilepsy and 195 with PNES were evaluated. One in 32 patients with epilepsy and 1 in 8 with PNES had at least 1 in-session seizure. A seizure occurred in 1 in 136 treatment sessions provided to patients with epilepsy, and 1 in 36 sessions provided to those with PNES. The risk of in-session seizures was significantly greater in patients with PNES than in patients with epilepsy (odds ratio [OR] 4.4, 95% confidence interval [CI] 1.3-15.2). Seizures tended to occur in the first half of treatment programs and individual sessions and only disrupted sessions briefly. Only one patient with PNES required in-patient observation not involving overnight admission. SIGNIFICANCE: In-session seizures do occur and are much more common in patients with PNES than in those with epilepsy. Seizures rarely caused major disruption to psychological treatment, and could almost invariably be managed by the treating therapist without help from additional medical staff. Nonetheless, this research suggests that psychological therapy providers should anticipate the occurrence of in-session seizures and have safe management plans in place. The greater frequency of in-session seizures in PNES may add to our understanding of the mechanisms triggering these seizures.


Asunto(s)
Terapia Cognitivo-Conductual/métodos , Manejo de la Enfermedad , Trastornos Psicofisiológicos/diagnóstico , Trastornos Psicofisiológicos/terapia , Convulsiones/diagnóstico , Convulsiones/terapia , Terapia de Aceptación y Compromiso/métodos , Terapia de Aceptación y Compromiso/tendencias , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Terapia Cognitivo-Conductual/tendencias , Electroencefalografía/tendencias , Epilepsia/diagnóstico , Epilepsia/psicología , Epilepsia/terapia , Femenino , Humanos , Masculino , Persona de Mediana Edad , Trastornos Psicofisiológicos/psicología , Estudios Retrospectivos , Convulsiones/psicología , Resultado del Tratamiento , Adulto Joven
13.
Epilepsy Behav ; 78: 155-160, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-29245083

RESUMEN

The Wada test remains the traditional test for lateralizing language and memory function prior to epilepsy surgery. Functional imaging, particularly functional MRI (fMRI), has made progress in the language domain, but less so in the memory domain. Magnetoencephalography (MEG) has received less research attention, but shows promise, particularly for language lateralization. We recruited a consecutive sample of 19 patients with epilepsy who had completed presurgical work-up, including the Wada test, and compared fMRI (memory) and MEG (language and memory) with Wada test results. The main research question was the concordance between Wada and these two imaging techniques as preepilepsy surgery investigations. We were also interested in the acceptability of the three techniques to patients. Concordance rates (N=16) were nonsignificant (Cohen's Kappa) between fMRI and Wada test (memory) and between MEG and Wada test (memory and language). The Wada test was a well-established protocol used at several epilepsy surgery centers in the UK. Patients generally found the Wada test an odd, but not aversive procedure. Sixteen (84%) patients who were scanned reported some level of obtundation in MEG. We present these discordant findings in support of the position that functional imaging and the Wada test are distinctive procedures, with little in the way of overlapping mechanisms, and that patient's experience should be taken into account when procedures are selected and offered to them.


Asunto(s)
Mapeo Encefálico/métodos , Epilepsia/diagnóstico , Lateralidad Funcional/fisiología , Lenguaje , Imagen por Resonancia Magnética/métodos , Magnetoencefalografía/métodos , Neuroimagen , Adulto , Epilepsia/fisiopatología , Femenino , Humanos , Pruebas del Lenguaje , Masculino , Memoria , Persona de Mediana Edad , Valor Predictivo de las Pruebas
14.
Clin Psychol Psychother ; 25(3): 489-496, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29363837

RESUMEN

There is limited high-quality evidence supporting psychological treatments for functional neurological disorders (FNDs), and what evidence exists suggests that the impact of such treatments could be improved. One way to increase effectiveness is to utilize approaches that can have impact across heterogeneous FND presentations. Acceptance and Commitment Therapy (ACT) targets a transdiagnostic process called psychological flexibility and is used effectively to integrate multidisciplinary treatments in other clinical contexts. Here, we present a consecutive case series (N = 8) of a relatively brief (6 to 10 sessions) ACT intervention, delivered face to face by a clinical psychologist in an outpatient neuropsychology service. Treatment aimed to reduce symptom interference and improve mood via improvements in psychological flexibility. Service users presented with a range of FND symptoms (e.g., syncope, limb paralysis, and paraesthesia). Following treatment, 5 participants showed reliable improvements in symptom interference (Work and Social Adjustment Scale), 2 to the extent of clinical significance; 4 had reliable improvements in mood (Clinical Outcomes in Routine Evaluation-10), and 2 within the range of clinical significance. There were no reliable deteriorations in symptom interference or mood. Marked variation was apparent on the measure of psychological flexibility (Acceptance and Action Questionnaire II), with 4 reliable improvements, 3 within the range of clinical significance, and also 2 reliable deteriorations. These promising results suggest that further investigation of an ACT approach to FND is warranted. Future studies should include measures of psychological flexibility with greater comprehensibility.


Asunto(s)
Terapia de Aceptación y Compromiso/métodos , Trastornos de Conversión/psicología , Trastornos de Conversión/terapia , Adolescente , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Encuestas y Cuestionarios , Resultado del Tratamiento , Adulto Joven
16.
J Biol Chem ; 290(17): 10862-75, 2015 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-25759392

RESUMEN

Alzheimer disease (AD) is a degenerative tauopathy characterized by aggregation of Tau protein through the repeat domain to form intraneuronal paired helical filaments (PHFs). We report two cell models in which we control the inherent toxicity of the core Tau fragment. These models demonstrate the properties of prion-like recruitment of full-length Tau into an aggregation pathway in which template-directed, endogenous truncation propagates aggregation through the core Tau binding domain. We use these in combination with dissolution of native PHFs to quantify the activity of Tau aggregation inhibitors (TAIs). We report the synthesis of novel stable crystalline leucomethylthioninium salts (LMTX®), which overcome the pharmacokinetic limitations of methylthioninium chloride. LMTX®, as either a dihydromesylate or a dihydrobromide salt, retains TAI activity in vitro and disrupts PHFs isolated from AD brain tissues at 0.16 µM. The Ki value for intracellular TAI activity, which we have been able to determine for the first time, is 0.12 µM. These values are close to the steady state trough brain concentration of methylthioninium ion (0.18 µM) that is required to arrest progression of AD on clinical and imaging end points and the minimum brain concentration (0.13 µM) required to reverse behavioral deficits and pathology in Tau transgenic mice.


Asunto(s)
Enfermedad de Alzheimer/tratamiento farmacológico , Enfermedad de Alzheimer/metabolismo , Agregación Patológica de Proteínas/tratamiento farmacológico , Agregación Patológica de Proteínas/metabolismo , Proteínas tau/química , Proteínas tau/metabolismo , Animales , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Línea Celular , Humanos , Azul de Metileno/análogos & derivados , Azul de Metileno/síntesis química , Azul de Metileno/química , Azul de Metileno/farmacología , Ratones , Ratones Transgénicos , Modelos Biológicos , Agregado de Proteínas/efectos de los fármacos , Dominios y Motivos de Interacción de Proteínas , Proteolisis , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo
17.
Epilepsy Behav ; 60: 149-152, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-27206234

RESUMEN

Good seizure outcomes and good psychosocial outcomes following epilepsy surgery do not necessarily follow one from the other. This study explored the relationship between several presurgical psychosocial characteristics and postsurgical quality-of-life outcomes. The study aimed to develop the concept of 'the burden of normality' and identify risk factors for a poor psychosocial outcome that could be targeted with ameliorative presurgery cognitive behavioral techniques. Data were collected from 77 epilepsy surgery patients from three UK epilepsy centers and presurgery and postsurgery follow-up data were obtained from 30-34 patients, depending on the measure. Measures were self-report. Postsurgery intervals were determined by the epilepsy surgery care pathway at individual centers. Presurgery poor levels of mental health, poor social functioning, increased belief in illness chronicity, and associating epilepsy with social role limitations were all associated with poor postsurgical quality of life. Adopting an accepting coping strategy presurgery was associated with good postoperative quality of life. Regression analysis showed that a good postsurgical quality of life was positively predicted by a presurgical coping style of being able to make the best of a situation and see challenges in a positive light (i.e., positive reinterpretation and growth from the COPE scale) and negatively predicted by presurgical levels of anxiety. These data are presented as an important step in identifying psychological red flags for an adverse psychosocial outcome to epilepsy surgery, as exemplified by the concept of the 'burden of normality' and specifying targets for preoperative ameliorative psychological advice.


Asunto(s)
Costo de Enfermedad , Epilepsia del Lóbulo Temporal/psicología , Epilepsia del Lóbulo Temporal/cirugía , Adaptación Psicológica , Adulto , Epilepsia del Lóbulo Temporal/diagnóstico , Femenino , Estudios de Seguimiento , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Calidad de Vida/psicología , Autoinforme , Ajuste Social , Resultado del Tratamiento
18.
Brain Inj ; 30(9): 1068-74, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27184946

RESUMEN

BACKGROUND: Whilst the scientific understanding of mild traumatic brain injury sequelae has advanced, the consequences of neurological insults sustained during football play in the form of multiple concussions and heading remains unclear. METHOD: To the authors' knowledge, this is the first longitudinal prospective study to follow-up a group of footballers and controls over time. Thirty-two elite young professional footballers were recruited and 24 were identified at follow-up. Thirty-three controls were recruited and 17 identified at follow-up. Medical examination, MRI (brain) imaging and detailed neuropsychological data were collected on the footballers at baseline and 5-year follow-up. Medical examination and detailed neuropsychological data were collected on the controls at baseline and 5-year follow-up. RESULTS: All participants had normal neurological examination at both time points. At baseline, 37% of the footballers had sustained minor neurological insults. Between baseline and 5 years, 66% of the footballers had sustained minor neurological insults. No MRI (brain) abnormalities were identified among the footballers at either time point. Regarding the neuropsychology, there was a 6-point IQ difference between footballers and controls, with the footballers being low. Test-re-test analysis on a range of carefully selected neurocognitive tests revealed a picture of good stability in cognitive functioning over this 5-year period. CONCLUSIONS: These longitudinal prospective data indicate no significant neurological, structural brain imaging or neuropsychological change among a sample of young elite professional footballers over the first 5 years of their professional career.


Asunto(s)
Atletas/psicología , Traumatismos en Atletas/diagnóstico por imagen , Lesiones Encefálicas/diagnóstico por imagen , Encéfalo/diagnóstico por imagen , Cognición/fisiología , Fútbol/lesiones , Adolescente , Traumatismos en Atletas/psicología , Atención/fisiología , Lesiones Encefálicas/psicología , Estudios de Seguimiento , Humanos , Estudios Longitudinales , Imagen por Resonancia Magnética , Masculino , Memoria/fisiología , Neuroimagen , Examen Neurológico , Pruebas Neuropsicológicas , Estudios Prospectivos , Adulto Joven
19.
BMC Genomics ; 16: 642, 2015 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-26311067

RESUMEN

BACKGROUND: Almost all genome sequencing projects neglect the fact that diploid organisms contain two genome copies and consequently what is published is a composite of the two. This means that the relationship between alternate alleles at two or more linked loci is lost. We have developed a simplified method of directly obtaining the haploid sequences of each genome copy from an individual organism. RESULTS: The diploid sequences of three groups of cattle samples were obtained using a simple sample preparation procedure requiring only a microscope and a haemocytometer. Samples were: 1) lymphocytes from a single Angus steer; 2) sperm cells from an Angus bull; 3) lymphocytes from East African Zebu (EAZ) cattle collected and processed in a field laboratory in Eastern Kenya. Haploid sequence from a fosmid library prepared from lymphocytes of an EAZ cow was used for comparison. Cells were serially diluted to a concentration of one cell per microlitre by counting with a haemocytometer at each dilution. One microlitre samples, each potentially containing a single cell, were lysed and divided into six aliquots (except for the sperm samples which were not divided into aliquots). Each aliquot was amplified with phi29 polymerase and sequenced. Contigs were obtained by mapping to the bovine UMD3.1 reference genome assembly and scaffolds were assembled by joining adjacent contigs that were within a threshold distance of each other. Scaffolds that appeared to contain artefacts of CNV or repeats were filtered out leaving scaffolds with an N50 length of 27-133 kb and a 88-98 % genome coverage. SNP haplotypes were assembled with the Single Individual Haplotyper program to generate an N50 size of 97-201 kb but only ~27-68 % genome coverage. This method can be used in any laboratory with no special equipment at only slightly higher costs than conventional diploid genome sequencing. A substantial body of software for analysis and workflow management was written and is available as supplementary data. CONCLUSIONS: We have developed a set of laboratory protocols and software tools that will enable any laboratory to obtain haplotype sequences at only modestly greater cost than traditional mixed diploid sequences.


Asunto(s)
Diploidia , Genoma , Genómica , Haplotipos , Análisis de Secuencia de ADN , Biología Computacional/métodos , Genómica/métodos , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Reproducibilidad de los Resultados , Análisis de Secuencia de ADN/métodos , Análisis de la Célula Individual , Programas Informáticos
20.
Nat Commun ; 15(1): 3644, 2024 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-38684655

RESUMEN

Despite expanded antiretroviral therapy (ART) in South Africa, HIV-1 transmission persists. Integrase strand transfer inhibitors (INSTI) and long-acting injectables offer potential for superior viral suppression, but pre-existing drug resistance could threaten their effectiveness. In a community-based study in rural KwaZulu-Natal, prior to widespread INSTI usage, we enroled 18,025 individuals to characterise HIV-1 drug resistance and transmission networks to inform public health strategies. HIV testing and reflex viral load quantification were performed, with deep sequencing (20% variant threshold) used to detect resistance mutations. Phylogenetic and geospatial analyses characterised transmission clusters. One-third of participants were HIV-positive, with 21.7% having detectable viral loads; 62.1% of those with detectable viral loads were ART-naïve. Resistance to older reverse transcriptase (RT)-targeting drugs was found, but INSTI resistance remained low (<1%). Non-nucleoside reverse transcriptase inhibitor (NNRTI) resistance, particularly to rilpivirine (RPV) even in ART-naïve individuals, was concerning. Twenty percent of sequenced individuals belonged to transmission clusters, with geographic analysis highlighting higher clustering in peripheral and rural areas. Our findings suggest promise for INSTI-based strategies in this setting but underscore the need for RPV resistance screening before implementing long-acting cabotegravir (CAB) + RPV. The significant clustering emphasises the importance of geographically targeted interventions to effectively curb HIV-1 transmission.


Asunto(s)
Farmacorresistencia Viral , Infecciones por VIH , VIH-1 , Filogenia , Población Rural , Carga Viral , Humanos , Infecciones por VIH/transmisión , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/virología , Infecciones por VIH/epidemiología , Farmacorresistencia Viral/genética , Sudáfrica/epidemiología , VIH-1/genética , VIH-1/efectos de los fármacos , Femenino , Masculino , Adulto , Persona de Mediana Edad , Carga Viral/efectos de los fármacos , Adulto Joven , Fármacos Anti-VIH/farmacología , Fármacos Anti-VIH/uso terapéutico , Adolescente , Mutación , Inhibidores de la Transcriptasa Inversa/uso terapéutico , Inhibidores de la Transcriptasa Inversa/farmacología , Inhibidores de Integrasa VIH/farmacología , Inhibidores de Integrasa VIH/uso terapéutico
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