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1.
Am J Respir Crit Care Med ; 209(2): 164-174, 2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-37938162

RESUMEN

Rationale: Respiratory metagenomics (RMg) needs evaluation in a pilot service setting to determine utility and inform implementation into routine clinical practice. Objectives: Feasibility, performance, and clinical impacts on antimicrobial prescribing and infection control were recorded during a pilot RMg service. Methods: RMg was performed on 128 samples from 87 patients with suspected lower respiratory tract infection (LRTI) on two general and one specialist respiratory ICUs at Guy's and St Thomas' NHS Foundation Trust, London. Measurements and Main Results: During the first 15 weeks, RMg provided same-day results for 110 samples (86%), with a median turnaround time of 6.7 hours (interquartile range = 6.1-7.5 h). RMg was 93% sensitive and 81% specific for clinically relevant pathogens compared with routine testing. Forty-eight percent of RMg results informed antimicrobial prescribing changes (22% escalation; 26% deescalation) with escalation based on speciation in 20 out of 24 cases and detection of acquired-resistance genes in 4 out of 24 cases. Fastidious or unexpected organisms were reported in 21 samples, including anaerobes (n = 12), Mycobacterium tuberculosis, Tropheryma whipplei, cytomegalovirus, and Legionella pneumophila ST1326, which was subsequently isolated from the bedside water outlet. Application to consecutive severe community-acquired LRTI cases identified Staphylococcus aureus (two with SCCmec and three with luk F/S virulence determinants), Streptococcus pyogenes (emm1-M1uk clone), S. dysgalactiae subspecies equisimilis (STG62647A), and Aspergillus fumigatus with multiple treatments and public health impacts. Conclusions: This pilot study illustrates the potential of RMg testing to provide benefits for antimicrobial treatment, infection control, and public health when provided in a real-world critical care setting. Multicenter studies are now required to inform future translation into routine service.


Asunto(s)
Antiinfecciosos , Infecciones del Sistema Respiratorio , Humanos , Proyectos Piloto , Londres , Unidades de Cuidados Intensivos , Infecciones del Sistema Respiratorio/diagnóstico , Infecciones del Sistema Respiratorio/tratamiento farmacológico
2.
Microbiol Immunol ; 68(2): 56-64, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38098134

RESUMEN

Vaccine development for herpes simplex virus 2 (HSV-2) has been attempted, but no vaccines are yet available. A plasmid-based reverse genetics system for Rotavirus (RV), which can cause gastroenteritis, allows the generation of recombinant RV containing foreign genes. In this study, we sought to develop simian RV (SA11) as a vector to express HSV-2 glycoprotein D (gD2) and evaluated its immunogenicity in mice. We generated the recombinant SA11-gD2 virus (rSA11-gD2) and confirmed its ability to express gD2 in vitro. The virus was orally inoculated into suckling BALB/c mice and into 8-week-old mice. Serum IgG and IgA titers against RV and gD2 were measured by ELISA. In the 8-week-old mice inoculated with rSA11-gD2, significant increases in not only antibodies against RV but also IgG against gD2 were demonstrated. In the suckling mice, antibodies against RV were induced, but gD2 antibody was not detected. Diarrhea observed after the first inoculation of rSA11-gD2 in suckling mice was similar to that induced by the parent virus. A gD2 expressing simian RV recombinant, which was orally inoculated, induced IgG against gD2. This strategy holds possibility for genital herpes vaccine development.


Asunto(s)
Herpes Genital , Rotavirus , Animales , Ratones , Herpesvirus Humano 2/genética , Rotavirus/genética , Genética Inversa , Proteínas del Envoltorio Viral/genética , Glicoproteínas/genética , Inmunoglobulina G , Anticuerpos Antivirales
3.
PLoS Pathog ; 16(9): e1008817, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32970782

RESUMEN

There is a clear requirement for an accurate SARS-CoV-2 antibody test, both as a complement to existing diagnostic capabilities and for determining community seroprevalence. We therefore evaluated the performance of a variety of antibody testing technologies and their potential use as diagnostic tools. Highly specific in-house ELISAs were developed for the detection of anti-spike (S), -receptor binding domain (RBD) and -nucleocapsid (N) antibodies and used for the cross-comparison of ten commercial serological assays-a chemiluminescence-based platform, two ELISAs and seven colloidal gold lateral flow immunoassays (LFIAs)-on an identical panel of 110 SARS-CoV-2-positive samples and 50 pre-pandemic negatives. There was a wide variation in the performance of the different platforms, with specificity ranging from 82% to 100%, and overall sensitivity from 60.9% to 87.3%. However, the head-to-head comparison of multiple sero-diagnostic assays on identical sample sets revealed that performance is highly dependent on the time of sampling, with sensitivities of over 95% seen in several tests when assessing samples from more than 20 days post onset of symptoms. Furthermore, these analyses identified clear outlying samples that were negative in all tests, but were later shown to be from individuals with mildest disease presentation. Rigorous comparison of antibody testing platforms will inform the deployment of point-of-care technologies in healthcare settings and their use in the monitoring of SARS-CoV-2 infections.


Asunto(s)
Anticuerpos Antivirales/análisis , Infecciones por Coronavirus/diagnóstico , Neumonía Viral/diagnóstico , Sistemas de Atención de Punto , Pruebas Serológicas/métodos , Adulto , Anciano , Betacoronavirus , COVID-19 , Prueba de COVID-19 , Técnicas de Laboratorio Clínico , Servicios de Salud Comunitaria , Proteínas de la Nucleocápside de Coronavirus , Ensayo de Inmunoadsorción Enzimática , Femenino , Hospitales , Humanos , Inmunoensayo , Mediciones Luminiscentes , Masculino , Persona de Mediana Edad , Proteínas de la Nucleocápside/inmunología , Pandemias , Fosfoproteínas , SARS-CoV-2 , Sensibilidad y Especificidad , Glicoproteína de la Espiga del Coronavirus/inmunología
4.
Crit Care Med ; 49(4): 697-701, 2021 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-33395069

RESUMEN

OBJECTIVES: Candida auris has been implicated in ICU outbreaks worldwide and is notable for being difficult to identify and treat, its resilience in the environment, and significant patient mortality associated with invasive disease. Here, we describe a small C. auris outbreak and how it was terminated. DESIGN: Single-center, observational. SETTING: Two general adult ICUs at an urban U.K. teaching hospital. PATIENTS: All patients positive for C. auris during the 5-month outbreak were included (n = 7). INTERVENTIONS: Stepwise implementation of enhanced infection prevention and control precautions was introduced including twice-weekly screening, contact tracing, isolation precautions, and environmental decontamination. A detailed environmental screen was performed to identify potential reservoirs. This included the patient bed space and clinical equipment and a frequently handled cloth lanyard attached to a key used to access controlled drugs. Personal possessions such as mobile phones, lanyards, and identification badges were also screened. MEASUREMENTS AND MAIN RESULTS: The index case and six linked acquisitions were identified. Four of six (67%) patients were identified after discharge of all known previous C. auris cases from ICU, highlighting potential for an environmental reservoir. Environmental screening identified C. auris from a patient bed space following deep cleaning, prompting review and enhancement of cleaning procedures. The controlled drug cloth lanyard was positive for C. auris, which prompted removal and culture of all staff lanyards. C. auris was identified on 1/100 staff lanyards (1%). No mobile phones or identification badges were positive for C. auris. The outbreak terminated following withdrawal of lanyards from ICU. CONCLUSIONS: This outbreak further implicates environmental reservoirs as sustaining C. auris ICU outbreaks. Identification of C. auris on cloth lanyards highlights the need to identify commonly handled moveable objects during an outbreak. We suggest that ICUs with a C. auris outbreak should investigate similar infrequently cleaned items as potential reservoirs and review their policies on lanyard use.


Asunto(s)
Antifúngicos/uso terapéutico , Vestuario/efectos adversos , Farmacorresistencia Fúngica , Control de Infecciones/métodos , Adulto , Candida , Transmisión de Enfermedad Infecciosa/prevención & control , Femenino , Humanos , Unidades de Cuidados Intensivos , Masculino , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad
5.
PLoS Pathog ; 15(6): e1007884, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-31206552

RESUMEN

In contrast to human cells, very few HSV-1 genes are known to be spliced, although the same pre-mRNA processing machinery is shared. Here, through global analysis of splice junctions in cells infected with HSV-1 and an HSV-1 mutant virus with deletion of infectious cell culture protein 27 (ICP27), one of two viral immediate early (IE) genes essential for viral replication, we identify hundreds of novel alternative splice junctions mapping to both previously known HSV-1 spliced genes and previously unknown spliced genes, the majority of which alter the coding potential of viral genes. Quantitative and qualitative splicing efficiency analysis of these novel alternatively spliced genes based on RNA-Seq and RT-PCR reveals that splicing at these novel splice sites is efficient only when ICP27 is absent; while in wildtype HSV-1 infected cells, the splicing of these novel splice junctions is largely silenced in a gene/sequence specific manner, suggesting that ICP27 not only promotes accumulation of ICP27 targeted transcripts but also ensures correctness of the functional coding sequences through inhibition of alternative splicing. Furthermore, ICP27 toggles expression of ICP34.5, the major viral neurovirulence factor, through inhibition of splicing and activation of a proximal polyadenylation signal (PAS) in the newly identified intron, revealing a novel regulatory mechanism for expression of a viral gene. Thus, through the viral IE protein ICP27, HSV-1 co-opts both splicing and polyadenylation machinery to achieve optimal viral gene expression during lytic infection. On the other hand, during latent infection when ICP27 is absent, HSV-1 likely takes advantages of host splicing machinery to restrict expression of randomly activated antigenic viral genes to achieve immune evasion.


Asunto(s)
Regulación Viral de la Expresión Génica , Herpesvirus Humano 1/fisiología , Proteínas Inmediatas-Precoces/biosíntesis , Poliadenilación , Precursores del ARN/metabolismo , Empalme del ARN , ARN Viral/metabolismo , Latencia del Virus/fisiología , Células HEK293 , Humanos , Proteínas Inmediatas-Precoces/genética , Precursores del ARN/genética , ARN Viral/genética , Proteínas Virales/biosíntesis , Proteínas Virales/genética
6.
Analyst ; 145(16): 5638-5646, 2020 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-32638712

RESUMEN

An evaluation of a rapid portable gold-nanotechnology measuring SARS-CoV-2 IgM, IgA and IgG antibody concentrations against spike 1 (S1), spike 2 (S) and nucleocapsid (N) was conducted using serum samples from 74 patients tested for SARS-CoV-2 RNA on admission to hospital, and 47 historical control patients from March 2019. 59 patients were RNA(+) and 15 were RNA(-). A serum (±) classification was derived for all three antigens and a quantitative serological profile was obtained. Serum(+) was identified in 30% (95% CI 11-48) of initially RNA(-) patients, in 36% (95% CI 17-54) of RNA(+) patients before 10 days, 77% (95% CI 67-87) between 10 and 20 days and 95% (95% CI 86-100) after 21 days. The patient-level diagnostic accuracy relative to RNA(±) after 10 days displayed 88% sensitivity (95% CI 75-95) and 75% specificity (95% CI 22-99), although specificity compared with historical controls was 100% (95%CI 91-100). This study provides robust support for further evaluation and validation of this novel technology in a clinical setting and highlights challenges inherent in assessment of serological tests for an emerging disease such as COVID-19.


Asunto(s)
Anticuerpos Antivirales/análisis , Betacoronavirus/inmunología , Infecciones por Coronavirus/diagnóstico , Neumonía Viral/diagnóstico , Pruebas Serológicas/métodos , Adulto , Anciano , Anciano de 80 o más Años , Anticuerpos Antivirales/inmunología , COVID-19 , Prueba de COVID-19 , Técnicas de Laboratorio Clínico , Estudios de Cohortes , Infecciones por Coronavirus/sangre , Proteínas de la Nucleocápside de Coronavirus , Reacciones Falso Negativas , Femenino , Oro/química , Humanos , Inmunoglobulina A/análisis , Inmunoglobulina A/inmunología , Inmunoglobulina G/análisis , Inmunoglobulina G/inmunología , Inmunoglobulina M/análisis , Inmunoglobulina M/inmunología , Masculino , Nanopartículas del Metal/química , Persona de Mediana Edad , Proteínas de la Nucleocápside/inmunología , Pandemias , Fosfoproteínas , Neumonía Viral/sangre , SARS-CoV-2 , Sensibilidad y Especificidad , Glicoproteína de la Espiga del Coronavirus/inmunología , Adulto Joven
7.
J Virol ; 92(14)2018 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-29720520

RESUMEN

Despite the long-standing observation that herpes simplex virus (HSV) latency-associated transcript (LAT) promoter deletion viruses show impaired recurrence phenotypes in relevant animal models, the mechanism by which these sequences exert this phenotypic effect is unknown. We constructed and evaluated four mutant HSV-2 isolates with targeted mutations in the LAT promoter and LAT-associated microRNAs (miRNAs) affecting (i) the LAT TATA box; (ii) the LAT ICP4-binding site; (iii) miRNA I (miR-I) and miR-II (miR-I/II), which both target ICP34.5; and (iv) miR-III, which targets ICP0. While the LAT TATA box mutant caused milder acute infections than wild-type (WT) virus, there was no difference in the recurrence phenotype between these viruses. LAT and miRNA expression during latency was not impaired by this mutation, suggesting that other promoter elements may be more important for latent HSV-2 LAT expression. Mutation of the LAT ICP4-binding site also did not cause an in vivo phenotypic difference between mutant and WT viruses. Acute infection and reactivation from latency of the miR-I/II mutant were similar to those of its rescuant, although the acute infection was slightly reduced in severity relative to that caused by the wild-type virus. The miR-III mutant also exhibited WT phenotypes in acute and recurrent phases of infection. While they do not rule out an effect of these elements in human latency or reactivation, these findings do not identify a specific role for LAT or LAT-associated miRNAs in the HSV-2 LAT promoter deletion phenotype in guinea pigs. Thus, other sequences in this region may play a more important role in the long-studied LAT-associated phenotype in animals.IMPORTANCE While it has been known for several decades that specific HSV-1 and HSV-2 sequences near the LAT promoter are required for efficient viral reactivation in animal models, the mechanism is still not known. We constructed four mutant viruses with the goal of identifying critical sequence elements and of specifically testing the hypothesis that microRNAs that are expressed during latency play a role. Determination that specific LAT promoter sequences and miRNA sequences do not influence viral reactivation of HSV-2 helps to narrow down the search for the mechanism by which the virus controls its latency and recurrence phenotype.


Asunto(s)
Herpes Simple/virología , Herpesvirus Humano 2/fisiología , MicroARNs/genética , Mutación , Proteínas Virales/genética , Activación Viral/genética , Latencia del Virus/genética , Animales , Femenino , Regulación Viral de la Expresión Génica , Cobayas , Herpes Simple/genética , Herpes Simple/metabolismo , Regiones Promotoras Genéticas , ARN Viral , Vagina/virología
8.
Proc Natl Acad Sci U S A ; 113(43): 12256-12261, 2016 10 25.
Artículo en Inglés | MEDLINE | ID: mdl-27791013

RESUMEN

The herpes simplex virus (HSV) infected cell culture polypeptide 27 (ICP27) protein is essential for virus infection of cells. Recent studies suggested that ICP27 inhibits splicing in a gene-specific manner via an unknown mechanism. Here, RNA-sequencing revealed that ICP27 not only inhibits splicing of certain introns in <1% of cellular genes, but also can promote use of alternative 5' splice sites. In addition, ICP27 induced expression of pre-mRNAs prematurely cleaved and polyadenylated from cryptic polyadenylation signals (PAS) located in intron 1 or 2 of ∼1% of cellular genes. These previously undescribed prematurely cleaved and polyadenylated pre-mRNAs, some of which contain novel ORFs, were typically intronless, <2 Kb in length, expressed early during viral infection, and efficiently exported to cytoplasm. Sequence analysis revealed that ICP27-targeted genes are GC-rich (as are HSV genes), contain cytosine-rich sequences near the 5' splice site, and have suboptimal splice sites in the impacted intron, suggesting that a common mechanism is shared between ICP27-mediated alternative polyadenylation and splicing. Optimization of splice site sequences or mutation of nearby cytosines eliminated ICP27-mediated splicing inhibition, and introduction of C-rich sequences to an ICP27-insensitive splicing reporter conferred this phenotype, supporting the inference that specific gene sequences confer susceptibility to ICP27. Although HSV is the first virus and ICP27 is the first viral protein shown to activate cryptic PASs in introns, we suspect that other viruses and cellular genes also encode this function.


Asunto(s)
Empalme Alternativo/genética , Proteínas Inmediatas-Precoces/genética , Simplexvirus/genética , Animales , Línea Celular , Chlorocebus aethiops , Humanos , Intrones/genética , Poliadenilación/genética , Precursores del ARN/genética , Sitios de Empalme de ARN/genética , Estabilidad del ARN/genética
9.
PLoS Med ; 13(1): e1001944, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26812054

RESUMEN

BACKGROUND: Identifying and tackling the social determinants of infectious diseases has become a public health priority following the recognition that individuals with lower socioeconomic status are disproportionately affected by infectious diseases. In many parts of the world, epidemiologically and genotypically defined community-associated (CA) methicillin-resistant Staphylococcus aureus (MRSA) strains have emerged to become frequent causes of hospital infection. The aim of this study was to use spatial models with adjustment for area-level hospital attendance to determine the transmission niche of genotypically defined CA- and health-care-associated (HA)-MRSA strains across a diverse region of South East London and to explore a potential link between MRSA carriage and markers of social and material deprivation. METHODS AND FINDINGS: This study involved spatial analysis of cross-sectional data linked with all MRSA isolates identified by three National Health Service (NHS) microbiology laboratories between 1 November 2011 and 29 February 2012. The cohort of hospital-based NHS microbiology diagnostic services serves 867,254 usual residents in the Lambeth, Southwark, and Lewisham boroughs in South East London, United Kingdom (UK). Isolates were classified as HA- or CA-MRSA based on whole genome sequencing. All MRSA cases identified over 4 mo within the three-borough catchment area (n = 471) were mapped to small geographies and linked to area-level aggregated socioeconomic and demographic data. Disease mapping and ecological regression models were used to infer the most likely transmission niches for each MRSA genetic classification and to describe the spatial epidemiology of MRSA in relation to social determinants. Specifically, we aimed to identify demographic and socioeconomic population traits that explain cross-area extra variation in HA- and CA-MRSA relative risks following adjustment for hospital attendance data. We explored the potential for associations with the English Indices of Deprivation 2010 (including the Index of Multiple Deprivation and several deprivation domains and subdomains) and the 2011 England and Wales census demographic and socioeconomic indicators (including numbers of households by deprivation dimension) and indicators of population health. Both CA-and HA-MRSA were associated with household deprivation (CA-MRSA relative risk [RR]: 1.72 [1.03-2.94]; HA-MRSA RR: 1.57 [1.06-2.33]), which was correlated with hospital attendance (Pearson correlation coefficient [PCC] = 0.76). HA-MRSA was also associated with poor health (RR: 1.10 [1.01-1.19]) and residence in communal care homes (RR: 1.24 [1.12-1.37]), whereas CA-MRSA was linked with household overcrowding (RR: 1.58 [1.04-2.41]) and wider barriers, which represent a combined score for household overcrowding, low income, and homelessness (RR: 1.76 [1.16-2.70]). CA-MRSA was also associated with recent immigration to the UK (RR: 1.77 [1.19-2.66]). For the area-level variation in RR for CA-MRSA, 28.67% was attributable to the spatial arrangement of target geographies, compared with only 0.09% for HA-MRSA. An advantage to our study is that it provided a representative sample of usual residents receiving care in the catchment areas. A limitation is that relationships apparent in aggregated data analyses cannot be assumed to operate at the individual level. CONCLUSIONS: There was no evidence of community transmission of HA-MRSA strains, implying that HA-MRSA cases identified in the community originate from the hospital reservoir and are maintained by frequent attendance at health care facilities. In contrast, there was a high risk of CA-MRSA in deprived areas linked with overcrowding, homelessness, low income, and recent immigration to the UK, which was not explainable by health care exposure. Furthermore, areas adjacent to these deprived areas were themselves at greater risk of CA-MRSA, indicating community transmission of CA-MRSA. This ongoing community transmission could lead to CA-MRSA becoming the dominant strain types carried by patients admitted to hospital, particularly if successful hospital-based MRSA infection control programmes are maintained. These results suggest that community infection control programmes targeting transmission of CA-MRSA will be required to control MRSA in both the community and hospital. These epidemiological changes will also have implications for effectiveness of risk-factor-based hospital admission MRSA screening programmes.


Asunto(s)
Infecciones Comunitarias Adquiridas/epidemiología , Infección Hospitalaria , Privación Materna , Staphylococcus aureus Resistente a Meticilina , Aislamiento Social , Infecciones Estafilocócicas/epidemiología , Adolescente , Adulto , Anciano , Niño , Preescolar , Infecciones Comunitarias Adquiridas/diagnóstico , Infecciones Comunitarias Adquiridas/psicología , Estudios Transversales , Interpretación Estadística de Datos , Femenino , Humanos , Lactante , Recién Nacido , Londres/epidemiología , Masculino , Staphylococcus aureus Resistente a Meticilina/aislamiento & purificación , Persona de Mediana Edad , Aislamiento Social/psicología , Infecciones Estafilocócicas/diagnóstico , Infecciones Estafilocócicas/psicología , Adulto Joven
10.
J Antimicrob Chemother ; 71(12): 3556-3561, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27516471

RESUMEN

BACKGROUND: Carbapenemase-producing Enterobacteriaceae (CPE) are an emerging threat for healthcare providers worldwide. OBJECTIVES: To determine CPE carriage rates and risk factors in an unselected hospital cohort at the time of admission. METHODS: We approached 4567 patients within 72 h of admission to provide a rectal swab and answer a questionnaire on risk factors for carriage. Rectal swabs were cultured for carbapenem-resistant organisms on chromogenic and non-chromogenic agar, and tested for carbapenemase production by PCR (Check-Direct CPE). The study was approved by the NHS Research Ethics Committee. RESULTS: Only 6 CPE were cultured from 5 (0.1%) of 4006 patients who provided a rectal swab; only 1 was cultured using non-chromogenic media. An additional 76 culture-negative rectal swabs were initially PCR positive, but none grew a carbapenem-resistant organism despite enrichment culture and only two were positive when retested several months later by Check-Direct and a second PCR assay (Cepheid GeneXpert® Carba-R). A modified Ct cut-off of <35 would have resolved these apparent false-positives. 40% of patients had a risk factor that should prompt screening and pre-emptive isolation as defined by UK CPE guidelines but only 8.1% and 20.2% of these patients had been screened and pre-emptively isolated by clinical teams, respectively. Overseas hospitalization was the only significant risk factor for CPE carriage (P < 0.001, OR 64.3, 95% CI 7.3-488.5). CONCLUSIONS: This study highlights a very low carriage rate of CPE. Hospitalization abroad is the most important risk factor to guide admission screening in this low-prevalence setting.


Asunto(s)
Proteínas Bacterianas/análisis , Pruebas Diagnósticas de Rutina/métodos , Infecciones por Enterobacteriaceae/diagnóstico , Infecciones por Enterobacteriaceae/microbiología , Enterobacteriaceae/enzimología , beta-Lactamasas/análisis , Adulto , Técnicas Bacteriológicas , Portador Sano/diagnóstico , Portador Sano/epidemiología , Portador Sano/microbiología , Enterobacteriaceae/aislamiento & purificación , Infecciones por Enterobacteriaceae/epidemiología , Femenino , Técnicas de Genotipaje , Hospitales , Humanos , Masculino , Tamizaje Masivo/normas , Tamizaje Masivo/estadística & datos numéricos , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , Prevalencia , Recto/microbiología , Encuestas y Cuestionarios , Reino Unido
11.
J Virol ; 89(9): 4837-48, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25673716

RESUMEN

UNLABELLED: In order to understand factors that may influence latency-associated transcription and latency-associated transcript (LAT) phenotypes, we studied the expression of the herpes simplex virus 2 (HSV-2) LAT-associated microRNAs (miRNAs). We mapped the transcription initiation sites of all three primary miRNA transcripts and identified the ICP4-binding sequences at the transcription initiation sites of both HSV-2 LAT (pri-miRNA for miR-I and miR-II, which target ICP34.5, and miR-III, which targets ICP0) and L/ST (a pri-miRNA for miR-I and miR-II) but not at that of the primary miR-H6 (for which the target is unknown). We confirmed activity of the putative HSV-2 L/ST promoter and found that ICP4 trans-activates the L/ST promoter when the ICP4-binding site at its transcription initiation site is mutated, suggesting that ICP4 may play a dual role in regulating transcription of L/ST and, consequently, of miR-I and miR-II. LAT exon 1 (containing LAT enhancer sequences), together with the LAT promoter region, comprises a bidirectional promoter required for the expression of both LAT-encoded miRNAs and miR-H6 in latently infected mouse ganglia. The ability of ICP4 to suppress ICP34.5-targeting miRNAs and to activate lytic viral genes suggests that ICP4 could play a key role in the switch between latency and reactivation. IMPORTANCE: The HSV-2 LAT and viral miRNAs expressed in the LAT region are the most abundant viral transcripts during HSV latency. The balance between the expression of LAT and LAT-associated miRNAs and the expression of lytic viral transcripts from the opposite strand appears to influence whether individual HSV-infected neurons will be latently or productively infected. The outcome of neuronal infection may thus depend on regulation of gene expression of the corresponding primary miRNAs. In the present study, we characterize promoter sequences responsible for miRNA expression, including identification of the primary miRNA 5' ends and evaluation of ICP4 response. These findings provide further insight into the virus' strategy to tightly control expression of lytic cycle genes (especially the neurovirulence factor, ICP34.5) and suggest a mechanism (via ICP4) for the transition from latency to reactivated productive infection.


Asunto(s)
Regulación Viral de la Expresión Génica , Herpesvirus Humano 2/genética , MicroARNs/biosíntesis , Animales , Sitios de Unión , Femenino , Perfilación de la Expresión Génica , Ratones , Regiones Promotoras Genéticas , Unión Proteica , Factores de Transcripción/metabolismo , Sitio de Iniciación de la Transcripción
12.
J Antimicrob Chemother ; 70(12): 3191-9, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26316381

RESUMEN

OBJECTIVES: Both low-level mupirocin resistance (LMR) and high-level mupirocin resistance (HMR) have been identified. The aim of this study was to determine the epidemiology of LMR and HMR in MRSA isolates at five hospitals that have used mupirocin for targeted decolonization as part of successful institutional control programmes. METHODS: All MRSA identified in three microbiology laboratories serving five central and south-east London hospitals and surrounding communities between November 2011 and February 2012 were included. HMR and LMR were determined by disc diffusion testing. WGS was used to derive multilocus sequence types (MLSTs) and the presence of HMR and LMR resistance determinants. RESULTS: Prevalence of either HMR or LMR amongst first healthcare episode isolates from 795 identified patients was 9.69% (95% CI 7.72-11.96); LMR was 6.29% (95% CI 4.70-8.21) and HMR was 3.40% (95% CI 2.25-4.90). Mupirocin resistance was not significantly different in isolates identified from inpatients at each microbiology laboratory, but was more common in genotypically defined 'hospital' rather than 'community' isolates (OR 3.17, 95% CI 1.36-9.30, P = 0.002). LMR was associated with inpatient stay, previous history of MRSA and age ≥65 years; HMR was associated with age ≥65 years and residential postcode outside London. LMR and HMR varied by clone, with both being low in the dominant UK MRSA clone ST22 compared with ST8, ST36 and ST239/241 for LMR and with ST8 and ST36 for HMR. V588F mutation and mupA carriage had high specificity (>97%) and area under the curve (>83%) to discriminate phenotypic mupirocin resistance, but uncertainty around the sensitivity point estimate was large (95% CI 52.50%-94.44%). Mutations in or near the mupA gene were found in eight isolates that carried mupA but were not HMR. CONCLUSIONS: Mupirocin resistance was identified in <10% of patients and varied significantly by clone, implying that changes in clonal epidemiology may have an important role in determining the prevalence of resistance in conjunction with selection due to mupirocin use.


Asunto(s)
Antiinfecciosos Locales/farmacología , Farmacorresistencia Bacteriana , Variación Genética , Staphylococcus aureus Resistente a Meticilina/clasificación , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Mupirocina/farmacología , Infecciones Estafilocócicas/epidemiología , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Pruebas Antimicrobianas de Difusión por Disco , Femenino , Genoma Bacteriano , Genotipo , Humanos , Londres/epidemiología , Masculino , Staphylococcus aureus Resistente a Meticilina/genética , Staphylococcus aureus Resistente a Meticilina/aislamiento & purificación , Epidemiología Molecular , Tipificación de Secuencias Multilocus , Prevalencia , Análisis de Secuencia de ADN , Infecciones Estafilocócicas/microbiología
13.
J Virol ; 87(10): 5820-30, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23487469

RESUMEN

Herpes simplex virus 1 (HSV-1) and HSV-2, two closely related neurotropic human herpesviruses, achieve neurotropism through ICP34.5, a major viral neurovirulence factor. In this report, in addition to the full-length 38-kDa protein (ICP34.5α), we identified a 28-kDa novel form of ICP34.5 (ICP34.5ß) in HSV-2-infected cells. ICP34.5ß is translated from unspliced ICP34.5 mRNA, with the retained intron introducing a premature stop codon. Thus, ICP34.5ß lacks the C-terminal conserved GADD34 domain but includes 19 additional amino acids encoded by the intron. Although a fraction of both HSV-2 ICP34.5 proteins are detected in the nucleolus, ICP34.5α is predominantly located in cytoplasm, and ICP34.5ß is mainly detected more diffusely in the nucleus. ICP34.5ß is unable to counteract PKR-mediated eIF2 phosphorylation but does not interfere with ICP34.5α's function in this process. Efficient expression of ICP34.5ß in cell culture assays is dependent on viral infection or expression of ICP27, a multifunctional immediate-early gene. The effect of ICP27 on the ICP34.5ß protein level is attributed to its selective inhibition of ICP34.5 splicing, which results in increased expression of ICP34.5ß but a reduced level of ICP34.5α. The C- terminal KH3 domain but not the RNA binding domain of ICP27 is required for its specific inhibition of ICP34.5 splicing and promotion of ICP34.5ß expression. Our results suggest that the expression of ICP34.5α and ICP34.5ß is tightly regulated in HSV-2 and likely contributes to viral pathogenesis.


Asunto(s)
Empalme Alternativo , Herpesvirus Humano 2/genética , Herpesvirus Humano 2/patogenicidad , Proteínas Virales/biosíntesis , Factores de Virulencia/biosíntesis , Animales , Línea Celular , Núcleo Celular/química , Citoplasma/química , Humanos , Proteínas Virales/genética , Factores de Virulencia/genética
14.
CNS Drugs ; 38(4): 239-254, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38502289

RESUMEN

Drug-induced movement disorders (DIMDs) are associated with use of dopamine receptor blocking agents (DRBAs), including antipsychotics. The most common forms are drug-induced parkinsonism (DIP), dystonia, akathisia, and tardive dyskinesia (TD). Although rare, neuroleptic malignant syndrome (NMS) is a potentially life-threatening consequence of DRBA exposure. Recommendations for anticholinergic use in patients with DIMDs were developed on the basis of a roundtable discussion with healthcare professionals with extensive expertise in DIMD management, along with a comprehensive literature review. The roundtable agreed that "extrapyramidal symptoms" is a non-specific term that encompasses a range of abnormal movements. As such, it contributes to a misconception that all DIMDs can be treated in the same way, potentially leading to the misuse and overprescribing of anticholinergics. DIMDs are neurobiologically and clinically distinct, with different treatment paradigms and varying levels of evidence for anticholinergic use. Whereas evidence indicates anticholinergics can be effective for DIP and dystonia, they are not recommended for TD, akathisia, or NMS; nor are they supported for preventing DIMDs except in individuals at high risk for acute dystonia. Anticholinergics may induce serious peripheral adverse effects (e.g., urinary retention) and central effects (e.g., impaired cognition), all of which can be highly concerning especially in older adults. Appropriate use of anticholinergics therefore requires careful consideration of the evidence for efficacy (e.g., supportive for DIP but not TD) and the risks for serious adverse events. If used, anticholinergic medications should be prescribed at the lowest effective dose and for limited periods of time. When discontinued, they should be tapered gradually.


Asunto(s)
Antipsicóticos , Distonía , Trastornos Distónicos , Trastornos del Movimiento , Síndrome Neuroléptico Maligno , Discinesia Tardía , Humanos , Anciano , Distonía/inducido químicamente , Distonía/tratamiento farmacológico , Antagonistas Colinérgicos/efectos adversos , Agitación Psicomotora/tratamiento farmacológico , Trastornos del Movimiento/tratamiento farmacológico , Trastornos del Movimiento/etiología , Discinesia Tardía/inducido químicamente , Discinesia Tardía/tratamiento farmacológico , Antipsicóticos/efectos adversos
15.
J Cyst Fibros ; 2024 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-38388235

RESUMEN

BACKGROUND: In 2017, the US Food and Drug Administration initiated expansion of drug labels for the treatment of cystic fibrosis (CF) to include CF transmembrane conductance regulator (CFTR) gene variants based on in vitro functional studies. This study aims to identify CFTR variants that result in increased chloride (Cl-) transport function by the CFTR protein after treatment with the CFTR modulator combination elexacaftor/tezacaftor/ivacaftor (ELX/TEZ/IVA). These data may benefit people with CF (pwCF) who are not currently eligible for modulator therapies. METHODS: Plasmid DNA encoding 655 CFTR variants and wild-type (WT) CFTR were transfected into Fisher Rat Thyroid cells that do not natively express CFTR. After 24 h of incubation with control or TEZ and ELX, and acute addition of IVA, CFTR function was assessed using the transepithelial current clamp conductance assay. Each variant's forskolin/cAMP-induced baseline Cl- transport activity, responsiveness to IVA alone, and responsiveness to the TEZ/ELX/IVA combination were measured in three different laboratories. Western blots were conducted to evaluate CFTR protein maturation and complement the functional data. RESULTS AND CONCLUSIONS: 253 variants not currently approved for CFTR modulator therapy showed low baseline activity (<10 % of normal CFTR Cl- transport activity). For 152 of these variants, treatment with ELX/TEZ/IVA improved the Cl- transport activity by ≥10 % of normal CFTR function, which is suggestive of clinical benefit. ELX/TEZ/IVA increased CFTR function by ≥10 percentage points for an additional 140 unapproved variants with ≥10 % but <50 % of normal CFTR function at baseline. These findings significantly expand the number of rare CFTR variants for which ELX/TEZ/IVA treatment should result in clinical benefit.

16.
J Antimicrob Chemother ; 68(5): 992-9, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23288405

RESUMEN

OBJECTIVES: The increasing use of chlorhexidine for methicillin-resistant Staphylococcus aureus (MRSA) decolonization raises concerns about reduced susceptibility. We evaluated the carriage of chlorhexidine resistance genes and chlorhexidine susceptibility in MRSA before and after introduction of an institutional MRSA control programme incorporating chlorhexidine-based decolonization in 2004. METHODS: MRSA bloodstream infection (BSI) isolates identified between 2001 and 2009 were tested for spa and staphylococcal cassette chromosome mec type and carriage of qacA, qacB and smr. Selected isolates were tested for chlorhexidine susceptibility. Logistic regression was used to evaluate associations between clone type, carriage of resistance genes and chlorhexidine susceptibility. Temporal trends in qacA or smr carriage were analysed using separate binomial generalized linear models. RESULTS: Typing identified two dominant clones: CC22 (n = 224) and CC30 (n = 197). Annual MRSA BSI rates declined from 2004, although the rate of decline for CC22 was slower than for CC30. Carriage of qacA and smr and having a chlorhexidine MIC ≥2 mg/L did not increase overall amongst MRSA BSI isolates; however, qacA carriage increased in CC22 compared with in CC30 (OR, 7.21; 95% CI, 1.32-39.17). Furthermore, qacA+ CC22 isolates were more likely to have a chlorhexidine MIC ≥2 mg/L than qacA+ CC30 isolates (OR, 21.67; CI, 2.54-185.20). CONCLUSIONS: A successful infection control programme was associated with the selection of qacA linked with a higher chlorhexidine MIC in one dominant endemic MRSA clone (CC22), but not another (CC30). The slower reduction in the CC22 MRSA BSI rate suggests that carriage of qacA confers a selective advantage, with implications for the sustainability of decolonization practice.


Asunto(s)
Proteínas Bacterianas/genética , Clorhexidina/farmacología , Desinfectantes/farmacología , Control de Infecciones/métodos , Proteínas de Transporte de Membrana/genética , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Selección Genética , Infecciones Estafilocócicas/microbiología , Bacteriemia/microbiología , Farmacorresistencia Bacteriana , Genotipo , Humanos , Staphylococcus aureus Resistente a Meticilina/clasificación , Staphylococcus aureus Resistente a Meticilina/genética , Staphylococcus aureus Resistente a Meticilina/aislamiento & purificación , Pruebas de Sensibilidad Microbiana , Epidemiología Molecular , Tipificación Molecular
17.
Clin Ther ; 45(12): 1222-1227, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37953076

RESUMEN

PURPOSE: One-capsule, once-daily valbenazine is approved for tardive dyskinesia and under evaluation for chorea associated with Huntington's disease, conditions in which patients often experience dysphagia. In vitro studies were conducted to assess the suitability of crushing the contents of valbenazine capsules (40 and 80 mg) for mixing with soft foods or liquids or administration via a gastrostomy tube (G-tube). METHODS: In study 1, the dissolution of whole valbenazine capsules and crushed capsule contents were measured serially for 1 hour. In study 2, valbenazine recovery was evaluated after crushed contents were mixed with soft foods, buffer solutions (pH range, 1.2-6.8), and fed-state simulated gastric fluid. In study 3, valbenazine recovery was evaluated after crushed contents were dispersed in water and delivered via a G-tube. In studies 2 and 3, acceptable valbenazine recovery was 90% to 110%. FINDINGS: Study 1 indicated rapid and complete drug release for whole valbenazine capsules and crushed capsule contents, with similar release at 10 minutes (whole, 94%-99%; crushed, 98%-100%) and 60 minutes (whole, 101%-103%; crushed, 101%-102%). Study 2 found acceptable valbenazine recovery within 2 hours of adding crushed capsule contents to tested foods, buffers, or fed-state simulated gastric fluid (recovery, 92%-102%). Study 3 found acceptable valbenazine recovery when crushed contents were added to cold or hot water and delivered via G-tube, with a water cup rinse to capture residual contents (recovery, 91%-97%). IMPLICATIONS: These studies indicate the potential viability of valbenazine formulation(s) that can be added to soft foods or liquids or delivered via G-tube. Such formulations will be important for individuals who require treatment with a vesicular monoamine transporter 2 inhibitor but cannot swallow whole pills.


Asunto(s)
Alimentos Especializados , Gastrostomía , Humanos , Tetrabenazina/farmacología , Tetrabenazina/uso terapéutico , Agua , Cápsulas
18.
Clin Infect Dis ; 54(5): 591-600, 2012 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-22186774

RESUMEN

INTRODUCTION: Antimicrobial resistance and bacterial virulence factors may increase the risk of hematogenous complications during methicillin-resistant Staphylococcus aureus (MRSA) bloodstream infection (BSI). This study reports on the impact of increasing vancomycin minimum inhibitory concentrations (V-MICs) and MRSA clone type on risk of hematogenous complications from MRSA BSI during implementation of an effective MRSA control program. METHODS: In sum, spa typing, staphylococcal cassette chromosome mec allotyping, and vancomycin and teicoplanin MICs were performed on 821 consecutive MRSA bloodstream isolates from 1999 to 2009. Prospectively collected data, including focus of infection, were available for 695 clinically significant cases. Logistic and multinomial logistic regression was used to determine the association between clone type, vancomycin MIC (V-MIC), and focus of infection. RESULTS: MRSA BSIs decreased by ∼90% during the 11 years. Typing placed isolates into 3 clonal complex (CC) groups that had different population median V-MICs (CC30, 0.5 µg/mL [n = 349]; CC22, 0.75 µg/mL [n = 272]; non-CC22/30, 1.5 µg/mL [n = 199]). There was a progressive increase in the proportion of isolates with a V-MIC above baseline median in each clonal group and a disproportionate fall in the clone group with lowest median V-MIC (CC30). In contrast, there were no increases in teicoplanin MICs. High V-MIC CC22 isolates (1.5-2 µg/mL) were strongly associated with endocarditis (odds ratio, 12; 95% confidence interval, 3.72-38.9) and with a septic metastasis after catheter-related BSI (odds ratio, 106; 95% confidence interval, 12.6-883) compared with other clone type/V-MIC combinations. CONCLUSIONS: An interaction between clone type and V-MIC can influence the risk of endocarditis associated with MRSA BSI, implying involvement of both therapeutic and host-pathogen factors.


Asunto(s)
Bacteriemia/microbiología , Endocarditis Bacteriana/epidemiología , Genotipo , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Staphylococcus aureus Resistente a Meticilina/genética , Infecciones Estafilocócicas/microbiología , Vancomicina/farmacología , Adulto , Anciano , Anciano de 80 o más Años , Endocarditis Bacteriana/microbiología , Femenino , Humanos , Masculino , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Riesgo
19.
J Virol ; 85(6): 3030-2, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21159869

RESUMEN

Levels of herpes simplex virus 1 (HSV-1) and HSV-2 DNA in dorsal root ganglia (DRG) and spinal cord (SC) were quantified after inoculation of guinea pig genitals and footpads. In genital infection, viral DNA reached SC and DRG simultaneously (at 2 to 3 days after inoculation) but was more abundant in SC than in DRG. After inoculation of footpads, which lack parasympathetic innervation, the viruses spread more efficiently to DRG than to SC. These results show important differences between genital and footpad infections, including independence of spread to DRG and SC, and imply that autonomic neurons may play an important role in the pathogenesis of viral latency after genital inoculation.


Asunto(s)
Ganglios Espinales/virología , Herpes Simple/virología , Herpesvirus Humano 1/aislamiento & purificación , Herpesvirus Humano 2/aislamiento & purificación , Médula Espinal/virología , Animales , ADN Viral/aislamiento & purificación , Femenino , Pie/virología , Genitales Femeninos/virología , Cobayas , Herpes Simple/patología , Herpesvirus Humano 1/patogenicidad , Herpesvirus Humano 2/patogenicidad
20.
J Virol ; 85(9): 4501-9, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21325410

RESUMEN

The herpes simplex virus 2 (HSV-2) viral microRNA (miRNA) designated miR-H6 is located upstream of the latency-associated transcript (LAT) promoter region on the strand opposite the LAT. Deletion of the LAT promoter and part of LAT exon 1 abolished HSV-2 miR-H6 expression in acutely and latently infected guinea pig dorsal root ganglia (DRG), suggesting that this region is needed both for the expression of LAT-encoded miRNAs and for miR-H6 expression in vivo. Relative to cells infected with a viral rescuant, miR-H6 expression was significantly reduced in cells infected with a mutant HSV-2 virus, NotPolyA, with an insertion of a simian virus (SV40) polyadenylation signal sequence between the LAT promoter and miR-H6 sequences. In addition, expression of miR-H6, but not LAT or viral DNA, was significantly reduced in both mouse trigeminal ganglia (TG) and guinea pig DRG latently infected with the NotPolyA mutant. Guinea pigs infected with NotPolyA experienced reduced neurological complications of acute infection relative to those infected with the rescuant, but the recurrence phenotype of the NotPolyA mutant was similar to those of its rescuant and wild-type HSV-2, indicating that reduction of miR-H6 expression is not by itself able to alter the establishment of latency for the wild-type virus or the recurrence phenotype. Furthermore, the mutation in NotPolyA did not affect the propensity of wild-type HSV-2 to establish latency in neurons positive for subtype marker KH10. In contrast to published reports regarding its HSV-1 homolog, HSV-2 miR-H6 did not affect ICP4 expression in transfected or infected cells. We hypothesize that viral miRNAs associated with LAT expression are likely to work collectively, contributing to the phenotype attributed to the LAT.


Asunto(s)
Regulación Viral de la Expresión Génica , Herpesvirus Humano 2/fisiología , MicroARNs/metabolismo , ARN Viral/metabolismo , Latencia del Virus , Animales , Femenino , Ganglios Espinales/virología , Cobayas , Herpesvirus Humano 2/genética , Ratones , Proteínas Virales/biosíntesis , Proteínas Virales/genética
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