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BACKGROUND: The World Health Organization (WHO) recommends rapid intravenous rehydration, using fluid volumes of 70-100mls/kg over 3-6 h, with some of the initial volume given rapidly as initial fluid boluses to treat hypovolaemic shock for children with acute gastroenteritis (AGE) and severe dehydration. The evidence supporting the safety and efficacy of rapid versus slower rehydration remains uncertain. METHODS: We conducted a systematic review of randomised controlled trials (RCTs) on 11th of May 2017 comparing different rates of intravenous fluid therapy in children with AGE and moderate or severe dehydration, using standard search terms. Two authors independently assessed trial quality and extracted data. Non-RCTs and non-English articles were excluded. The primary endpoint was mortality and secondary endpoints included adverse events (safety) and treatment efficacy. MAIN RESULTS: Of the 1390 studies initially identified, 18 were assessed for eligibility. Of these, 3 studies (n = 464) fulfilled a priori criteria for inclusion; most studied children with moderate dehydration and none were conducted in resource-poor settings. Volumes and rates of fluid replacement varied from 20 to 60 ml/kg given over 1-2 h (fast) versus 2-4 h (slow). There was substantial heterogeneity in methodology between the studies with only one adjudicated to be of high quality. There were no deaths in any study. Safety endpoints only identified oedema (n = 6) and dysnatraemia (n = 2). Pooled analysis showed no significant difference between the rapid and slow intravenous rehydration groups for the proportion of treatment failures (N = 468): pooled RR 1.30 (95% CI: 0.87, 1.93) and the readmission rates (N = 439): pooled RR 1.39 (95% CI: 0.68, 2.85). CONCLUSIONS: Despite wide implementation of WHO Plan C guideline for severe AGE, we found no clinical evaluation in resource-limited settings, and only limited evaluation of the rate and volume of rehydration in other parts of the world. Recent concerns over aggressive fluid expansion warrants further research to inform guidelines on rates of intravenous rehydration therapy for severe AGE.
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Desidratação/terapia , Hidratação/métodos , Gastroenterite/complicações , Doença Aguda , Adolescente , Criança , Pré-Escolar , Desidratação/etiologia , Humanos , Lactente , Recém-Nascido , Infusões Intravenosas , Ensaios Clínicos Controlados Aleatórios como Assunto , Risco , Fatores de Tempo , Resultado do TratamentoRESUMO
The φCh1 myovirus, which infects the haloalkaliphilic archaeon Natrialba magadii, contains an invertible region that comprises the convergent open reading frames (ORFs) 34 and 36, which code for the putative tail fibre proteins gp34 and gp36 respectively. The inversion leads to an exchange of the C-termini of these proteins, thereby creating different types of tail fibres. Gene expression experiments revealed that only ORF34 is transcribed, indicating that φCh1 produces tail fibre proteins exclusively from this particular ORF. Only one of the two types of tail fibres encoded by ORF34 is able to bind to Nab. magadii in vitro. This is reflected by the observation that during the early phases of the infection cycle, the lysogenic strain L11 carries its invertible region exclusively in the orientation that produces that specific type of tail fibre. Obviously, Nab. magadii can only be infected by viruses carrying this particular type of tail fibre. By mutational analysis, the binding domain of gp34 was localized to the C-terminal part of the protein, particularly to a galactose-binding domain. The involvement of galactose residues in cell adhesion was supported by the observation that the addition of α-D-galactose to purified gp34 or whole virions prevented their attachment to Nab. magadii.
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Bacteriófagos/fisiologia , Halobacteriaceae/virologia , Myoviridae/fisiologia , Proteínas Virais/metabolismo , Ligação Viral , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Bacteriófagos/química , Bacteriófagos/genética , Regulação Viral da Expressão Gênica , Halobacteriaceae/genética , Halobacteriaceae/metabolismo , Especificidade de Hospedeiro , Dados de Sequência Molecular , Myoviridae/química , Myoviridae/genética , Fases de Leitura Aberta , Estrutura Terciária de Proteína , Proteínas Virais/química , Proteínas Virais/genéticaRESUMO
In the study described here, we successfully developed a transformation system for halo(alkali)philic members of the Archaea. This transformation system comprises a series of Natrialba magadii/Escherichia coli shuttle vectors based on a modified method to transform halophilic members of the Archaea and genomic elements of the N. magadii virus Ch1. The shuttle vector pRo-5, based on the repH-containing region of Ch1, stably replicated in E. coli and N. magadii and in several halophilic and haloalkaliphilic members of the Archaea not transformable so far. The Ch1 operon ORF53/ORF54 (repH) was essential for pRo-5 replication and was thus identified as the minimal replication origin. The plasmid allowed homologous and heterologous gene expression, as exemplified by the expression of Ch1 ORF3452, which encodes a structural protein, and the reporter gene bgaH of Haloferax lucentense in N. magadii. The new transformation/vector system will facilitate genetic studies within N. magadii and other haloalkaliphilic archaea and will allow the detailed characterization of the gene functions of N. magadii virus Ch1 in their extreme environments.
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Vetores Genéticos , Halobacteriaceae/genética , Myoviridae/genética , Transformação Genética , DNA Viral/química , DNA Viral/genética , Escherichia coli/genética , Genes Reporter , Haloferax/genética , TransfecçãoRESUMO
OBJECTIVES: To report on population-based epidemiological trends in central nervous system (CNS) abscesses and empyemas in England over five decades. METHODS: Trend analyses of age-sex-specific hospital admission and death rates using routinely collected English national hospital discharge records, mortality records, and annual population denominators from 1968 to 2019. RESULTS: Hospital admission rates for CNS abscesses and empyemas were stable in England until the late 1980s. In the last two decades of the study period (1999-2019), first-time admissions increased from 1.24 per 100,000 population in 1999 (95% confidence interval [CI] 1.14-1.35) to 2.86 in 2019 (95% CI 2.72-3.01). Admission rates were highest among infants and older adults, and were higher for males than females. There were small but significant increases in annual mortality rates for CNS abscesses and empyemas over the last two decades of the study period after accounting for population ageing, but mortality remained low at around 0.1-0.2 per 100,000 population. Mortality increased with advancing age; deaths in childhood were extremely rare. Case fatality rates where a relevant diagnosis was recorded as either the underlying or contributing cause were 4.3% and 9.7% respectively. CONCLUSIONS: The increase in CNS abscesses and empyemas in England might reflect improved case ascertainment, but the likelihood of a true rise in incidence should be considered.
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Abscesso , Empiema , Lactente , Masculino , Feminino , Humanos , Idoso , Hospitalização , Inglaterra/epidemiologia , Sistema Nervoso CentralRESUMO
Confocal micro-x-ray fluorescence (µXRF) is a powerful tool to analyze the spatial distribution of major, minor, and trace elements in three dimensions. Typical (confocal) µXRF measurements in the lab use polychromatic excitation, complicating quantification and fundamental parameter-based corrections and furthermore deteriorating peak-to-background ratios due to scattered bremsstrahlung. The goal for the new setup was to remedy these problems, without sacrificing spatial resolution, and keep it flexible for different excitation energies and transportation to other sources. The source assembly consists of a water-cooled fine-focus x-ray diffraction tube and a parallel beam-mirror, which produces a quasi-parallel, monochromatic beam. The presented results were obtained using a 2 kW molybdenum tube and a mirror for Mo-Kα. The confocal setup itself consists of two polycapillary half-lenses, one for the source side and the other for the detector side, where a 50 mm2 silicon drift detector is mounted. Both polycapillaries have a focus size of â¼15 µm for Mo-Kα. The second polycapillary can also be exchanged for a custom-designed collimator in order to perform non-confocal µXRF. Details of the technical setup and results from technical and biological samples are presented. Detection limits for selected elements from Ca to Pb in the confocal and non-confocal mode were established (e.g., 1 µg/g non-confocal and 20 µg/g confocal for As) using the NIST standard reference materials (SRMs) 621 and 1412. Furthermore, the results of the measurements of SRM 621 were evaluated using the fundamental parameter based quantification software ATI-QUANT. The results are compared with the certified values and generally are in good agreement.
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INTRODUCTION: Infectious and immune-mediated encephalitides are important but under-recognised causes of morbidity and mortality in childhood, with a 7% death rate and up to 50% morbidity after prolonged follow-up. There is a theoretical basis for ameliorating the immune response with intravenous immunoglobulin (IVIG), which is supported by empirical evidence of a beneficial response following its use in the treatment of viral and autoimmune encephalitis. In immune-mediated encephalitis, IVIG is often used after a delay (by weeks in some cases), while diagnosis is confirmed. Wider use of IVIG in infectious encephalitis and earlier use in immune-mediated encephalitis could improve outcomes for these conditions. We describe the protocol for the first ever randomised control trial of IVIG treatment for children with all-cause encephalitis. METHODS AND ANALYSIS: 308 children (6â months to 16â years) with a diagnosis of acute/subacute encephalitis will be recruited in â¼30 UK hospitals and randomised to receive 2 doses (1â g/kg/dose) of either IVIG or matching placebo, in addition to standard treatment. Recruitment will be over a 42-month period and follow-up of each participant will be for 12 months post randomisation. The primary outcome is 'good recovery' (score of 2 or lower on the Glasgow Outcome Score Extended-paediatric version), at 12â months after randomisation. Additional secondary neurological measures will be collected at 4-6â weeks after discharge from acute care and at 6 and 12â months after randomisation. Safety, radiological, other autoimmune and tertiary outcomes will also be assessed. ETHICS AND DISSEMINATION: This trial has been approved by the UK National Research Ethics committee (South Central-Oxford A; REC 14/SC/1416). Current protocol: V4.0 (10/03/2016). The findings will be presented at national and international meetings and conferences and published in peer-reviewed journals. TRIAL REGISTRATION NUMBERS: NCT02308982, EudraCT201400299735 and ISRCTN15791925; Pre-results.
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Encefalite/tratamento farmacológico , Imunoglobulinas Intravenosas/uso terapêutico , Fatores Imunológicos/uso terapêutico , Adolescente , Criança , Pré-Escolar , Protocolos Clínicos , Encefalite/imunologia , Doença de Hashimoto/tratamento farmacológico , Doença de Hashimoto/imunologia , Humanos , Lactente , Encefalite Infecciosa/tratamento farmacológico , Encefalite Infecciosa/imunologia , Pediatria , Projetos de PesquisaRESUMO
phiCh1 is a temperate virus infecting the haloalkaliphilic archaeon Natrialba magadii. As for all temperate viruses, a control of the lysogenic state versus the lytic life cycle is essential. Two open reading frames (ORFs) have been identified as putative repressor encoding genes: ORF48 and ORF49. The protein of ORF48 showed sequence similarities to putative repressor molecules. ORF49 was identified by the analysis of a mutant of phiCh1: the lysogenic strain carrying mutant phiCh1-1 showed a different lysis behavior than wild type virus phiCh1, indicating a dysfunction in the regulation of gene expression. Here, we show that the intergenic region between ORF48 and ORF49 comprises a promoter/operator sequence that is a transcriptionally active region in the model system Haloferax volcanii. Transcription from this region can be repressed by the activity of the ORF48 gene product. Gp43/gp44 has an enhancing effect on this regulatory sequence. Evidence is given for a possible binding site of Rep and gp43/gp44 within the coding region of the rep gene.
Assuntos
Vírus de Archaea/genética , Halobacteriales/virologia , Lisogenia/genética , Regiões Operadoras Genéticas , Proteínas Repressoras/genética , Proteínas Virais/genética , Vírus de Archaea/metabolismo , Regulação Viral da Expressão Gênica/fisiologia , Halobacteriales/genética , Mutação , Fases de Leitura Aberta , Regiões Promotoras Genéticas , Transcrição Gênica/fisiologia , Proteínas Virais/metabolismoRESUMO
"This study addresses the issues and the consequences of the growth of [the] Igbo population [of Nigeria] from the pre-colonial period to the year 2000 and beyond; it reveals that though the political crises of the Nigerian Civil War have reduced the tempo of the growth of the population, the high fertility rate observed in Igbo society will over time lead to a rapid recovery in the growth of the population." (SUMMARY IN FRE AND ITA)